49 results on '"Octavio M"'
Search Results
2. Phylogeny and chromosomal diversification in the Dichroplus elongatus species group (Orthoptera, Melanoplinae).
- Author
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Elio R D Castillo, Alberto Taffarel, Maximiliano M Maronna, María Marta Cigliano, Octavio M Palacios-Gimenez, Diogo C Cabral-de-Mello, and Dardo A Martí
- Subjects
Medicine ,Science - Abstract
In an attempt to track the chromosomal differentiation in the Dichroplus elongatus species group, we analyzed the karyotypes of four species with classical cytogenetic and mapping several multigene families through fluorescent in situ hybridization (FISH). We improved the taxon sampling of the D. elongatus species group adding new molecular data to infer the phylogeny of the genus and reconstruct the karyotype evolution. Our molecular analyses recovered a fully resolved tree with no evidence for the monophyly of Dichroplus. However, we recovered several stable clades within the genus, including the D. elongatus species group, under the different strategies of tree analyses (Maximum Parsimony and Maximum Likelihood). The chromosomal data revealed minor variation in the D. elongatus species group's karyotypes caused by chromosome rearrangements compared to the phylogenetically related D. maculipennis species group. The karyotypes of D. intermedius and D. exilis described herein showed the standard characteristics found in most Dichroplini, 2n = 23/24, X0♂ XX♀, Fundamental number (FN) = 23/24. However, we noticed two established pericentric inversions in D. intermedius karyotype, raising the FN to 27♂/28♀. A strong variation in the heterochromatic blocks distribution was evidenced at interespecific level. The multigene families' mapping revealed significant variation, mainly in rDNA clusters. These variations are probably caused by micro chromosomal changes, such as movement of transposable elements (TEs) and ectopic recombination. These observations suggest a high genomic dynamism for these repetitive DNA sequences in related species. The reconstruction of the chromosome character "variation in the FN" posits the FN = 23/24 as the ancestral state, and it is hypothesized that variations due to pericentric inversions has arisen independently three times in the evolutionary history of Dichroplus. One of these independent events occurred in the D. elongatus species group, where D. intermedius is the unique case with the highest FN described in the tribe Dichroplini.
- Published
- 2017
- Full Text
- View/download PDF
3. Polarity-Dependent Misperception of Subjective Visual Vertical during and after Transcranial Direct Current Stimulation (tDCS).
- Author
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Taiza E G Santos-Pontelli, Brunna P Rimoli, Diandra B Favoretto, Suleimy C Mazin, Dennis Q Truong, Joao P Leite, Octavio M Pontes-Neto, Suzanne R Babyar, Michael Reding, Marom Bikson, and Dylan J Edwards
- Subjects
Medicine ,Science - Abstract
Pathologic tilt of subjective visual vertical (SVV) frequently has adverse functional consequences for patients with stroke and vestibular disorders. Repetitive transcranial magnetic stimulation (rTMS) of the supramarginal gyrus can produce a transitory tilt on SVV in healthy subjects. However, the effect of transcranial direct current stimulation (tDCS) on SVV has never been systematically studied. We investigated whether bilateral tDCS over the temporal-parietal region could result in both online and offline SVV misperception in healthy subjects. In a randomized, sham-controlled, single-blind crossover pilot study, thirteen healthy subjects performed tests of SVV before, during and after the tDCS applied over the temporal-parietal region in three conditions used on different days: right anode/left cathode; right cathode/left anode; and sham. Subjects were blind to the tDCS conditions. Montage-specific current flow patterns were investigated using computational models. SVV was significantly displaced towards the anode during both active stimulation conditions when compared to sham condition. Immediately after both active conditions, there were rebound effects. Longer lasting after-effects towards the anode occurred only in the right cathode/left anode condition. Current flow models predicted the stimulation of temporal-parietal regions under the electrodes and deep clusters in the posterior limb of the internal capsule. The present findings indicate that tDCS over the temporal-parietal region can significantly alter human SVV perception. This tDCS approach may be a potential clinical tool for the treatment of SVV misperception in neurological patients.
- Published
- 2016
- Full Text
- View/download PDF
4. Verticality Perceptions Associate with Postural Control and Functionality in Stroke Patients.
- Author
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Jussara A O Baggio, Suleimy S C Mazin, Frederico F Alessio-Alves, Camila G C Barros, Antonio A O Carneiro, João P Leite, Octavio M Pontes-Neto, and Taiza E G Santos-Pontelli
- Subjects
Medicine ,Science - Abstract
Deficits of postural control and perceptions of verticality are disabling problems observed in stroke patients that have been recently correlated to each other. However, there is no evidence in the literature confirming this relationship with quantitative posturography analysis. Therefore, the objectives of the present study were to analyze the relationship between Subjective Postural Vertical (SPV) and Haptic Vertical (HV) with posturography and functionality in stroke patients. We included 45 stroke patients. The study protocol was composed by clinical interview, evaluation of SPV and HV in roll and pitch planes and posturography. Posturography was measured in the sitting and standing positions under the conditions: eyes open, stable surface (EOSS); eyes closed, stable surface (ECSS); eyes open, unstable surface (EOUS); and eyes closed, unstable surface (ECUS). The median PV in roll plane was 0.34° (-1.44° to 2.54°) and in pitch plane 0.36° (-2.72° to 2.45°). The median of HV in roll and pitch planes were -0.94° (-5.86° to 3.84°) and 3.56° (-0.68° to 8.36°), respectively. SPV in the roll plane was correlated with all posturagraphy parameters in sitting position in all conditions (r = 0.35 to 0.47; p < 0.006). There were moderate correlations with the verticality perceptions and all the functional scales. Linear regression model showed association between speed and SPV in the roll plane in the condition EOSS (R2 of 0.37; p = 0.005), in the condition ECSS (R2 of 0.13; p = 0.04) and in the condition EOUS (R2 of 0.22; p = 0.03). These results suggest that verticality perception is a relevant component of postural control and should be systematically evaluated, particularly in patients with abnormal postural control.
- Published
- 2016
- Full Text
- View/download PDF
5. Heme oxygenase-1 protects corexit 9500A-induced respiratory epithelial injury across species.
- Author
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Fu Jun Li, Ryan N Duggal, Octavio M Oliva, Suman Karki, Ranu Surolia, Zheng Wang, R Douglas Watson, Victor J Thannickal, Mickie Powell, Stephen Watts, Tejaswini Kulkarni, Hitesh Batra, Subhashini Bolisetty, Anupam Agarwal, and Veena B Antony
- Subjects
Medicine ,Science - Abstract
The effects of Corexit 9500A (CE) on respiratory epithelial surfaces of terrestrial mammals and marine animals are largely unknown. This study investigated the role of CE-induced heme oxygenase-1 (HO-1), a cytoprotective enzyme with anti-apoptotic and antioxidant activity, in human bronchial airway epithelium and the gills of exposed aquatic animals. We evaluated CE-mediated alterations in human airway epithelial cells, mice lungs and gills from zebrafish and blue crabs. Our results demonstrated that CE induced an increase in gill epithelial edema and human epithelial monolayer permeability, suggesting an acute injury caused by CE exposure. CE induced the expression of HO-1 as well as C-reactive protein (CRP) and NADPH oxidase 4 (NOX4), which are associated with ROS production. Importantly, CE induced caspase-3 activation and subsequent apoptosis of epithelial cells. The expression of the intercellular junctional proteins, such as tight junction proteins occludin, zonula occludens (ZO-1), ZO-2 and adherens junctional proteins E-cadherin and Focal Adhesion Kinase (FAK), were remarkably inhibited by CE, suggesting that these proteins are involved in CE-induced increased permeability and subsequent apoptosis. The cytoskeletal protein F-actin was also disrupted by CE. Treatment with carbon monoxide releasing molecule-2 (CORM-2) significantly inhibited CE-induced ROS production, while the addition of HO-1 inhibitor, significantly increased CE-induced ROS production and apoptosis, suggesting a protective role of HO-1 or its reaction product, CO, in CE-induced apoptosis. Using HO-1 knockout mice, we further demonstrated that HO-1 protected against CE-induced inflammation and cellular apoptosis and corrected CE-mediated inhibition of E-cadherin and FAK. These observations suggest that CE activates CRP and NOX4-mediated ROS production, alters permeability by inhibition of junctional proteins, and leads to caspase-3 dependent apoptosis of epithelial cells, while HO-1 and its reaction products protect against oxidative stress and apoptosis.
- Published
- 2015
- Full Text
- View/download PDF
6. Contrasting the Chromosomal Organization of Repetitive DNAs in Two Gryllidae Crickets with Highly Divergent Karyotypes.
- Author
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Octavio M Palacios-Gimenez, Carlos Roberto Carvalho, Fernanda Aparecida Ferrari Soares, and Diogo C Cabral-de-Mello
- Subjects
Medicine ,Science - Abstract
A large percentage of eukaryotic genomes consist of repetitive DNA that plays an important role in the organization, size and evolution. In the case of crickets, chromosomal variability has been found using classical cytogenetics, but almost no information concerning the organization of their repetitive DNAs is available. To better understand the chromosomal organization and diversification of repetitive DNAs in crickets, we studied the chromosomes of two Gryllidae species with highly divergent karyotypes, i.e., 2n(♂) = 29,X0 (Gryllus assimilis) and 2n = 9, neo-X1X2Y (Eneoptera surinamensis). The analyses were performed using classical cytogenetic techniques, repetitive DNA mapping and genome-size estimation. Conserved characteristics were observed, such as the occurrence of a small number of clusters of rDNAs and U snDNAs, in contrast to the multiple clusters/dispersal of the H3 histone genes. The positions of U2 snDNA and 18S rDNA are also conserved, being intermingled within the largest autosome. The distribution and base-pair composition of the heterochromatin and repetitive DNA pools of these organisms differed, suggesting reorganization. Although the microsatellite arrays had a similar distribution pattern, being dispersed along entire chromosomes, as has been observed in some grasshopper species, a band-like pattern was also observed in the E. surinamensis chromosomes, putatively due to their amplification and clustering. In addition to these differences, the genome of E. surinamensis is approximately 2.5 times larger than that of G. assimilis, which we hypothesize is due to the amplification of repetitive DNAs. Finally, we discuss the possible involvement of repetitive DNAs in the differentiation of the neo-sex chromosomes of E. surinamensis, as has been reported in other eukaryotic groups. This study provided an opportunity to explore the evolutionary dynamics of repetitive DNAs in two non-model species and will contribute to the understanding of chromosomal evolution in a group about which little chromosomal and genomic information is known.
- Published
- 2015
- Full Text
- View/download PDF
7. How Many Patients Become Functionally Dependent after a Stroke? A 3-Year Population-Based Study in Joinville, Brazil
- Author
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Lívia Mizuki de Campos, Bruna Mariah Martins, Selma Cristina Franco, Octavio M. Pontes-Neto, Suleimy Cristina Mazin, Norberto Luiz Cabral, and Felipe Ibiapina dos Reis
- Subjects
Male ,Pediatrics ,Activities of daily living ,Social Sciences ,lcsh:Medicine ,Blood Pressure ,Stroke mortality ,Vascular Medicine ,Geographical locations ,Functionally dependent ,0302 clinical medicine ,Sociology ,Activities of Daily Living ,Medicine and Health Sciences ,Medicine ,Public and Occupational Health ,030212 general & internal medicine ,lcsh:Science ,Stroke ,PACIENTES ,education.field_of_study ,Multidisciplinary ,Incidence (epidemiology) ,Middle Aged ,Hospitals ,Hemorrhagic Stroke ,Neurology ,Population Surveillance ,Hypertension ,Female ,Brazil ,Research Article ,medicine.medical_specialty ,Cerebrovascular Diseases ,Population ,03 medical and health sciences ,Humans ,Social Stratification ,cardiovascular diseases ,education ,Ischemic Stroke ,Aged ,business.industry ,lcsh:R ,Physical Activity ,South America ,medicine.disease ,Health Care ,Population based study ,Telephone interview ,Health Care Facilities ,lcsh:Q ,People and places ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
The decrease in stroke mortality will increase the burden of survivors with functional dependence (FD). The aim of this study was to evaluate how many patients become functionally dependent over 3 years after an incident event in Joinville, Brazil. The proportion of FD (defined as a modified Rankin score 3 to 5) among stroke survivors from the Joinville Stroke Registry was assessed using a validated telephone interview. Incidence of FD after stroke in Joinville in one year was 23.24 per 100,000 population. The overall proportion of FD among stroke survivors at discharge was 32.7%. Of 303 patients with first-ever ischaemic stroke (IS), one-third were FD at discharge, and 12%, 9% and 8%, respectively at 1, 2 and 3 years. Among 37 patients with haemorrhagic stroke (HS), 38% were dependent at discharge, 16% after 1 and 2 years and 14% after 3. Among 27 patients with subarachnoid haemorrhage (SAH), 19% were dependent at discharge and 4% from 1 to 3 years. Among IS subtypes, cardioembolic ones had the worst risk of FD. (RR 19.8; 95% CI: 2.2 to 175.9). Our results showed that one-third of stroke survivors have FD during the first year after stroke in Brazil. Therefore, a city with half a million people might expect 120 new stroke patients with FD each year.
- Published
- 2017
8. Phylogeny and chromosomal diversification in the Dichroplus elongatus species group (Orthoptera, Melanoplinae)
- Author
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Castillo, Elio R. D., primary, Taffarel, Alberto, additional, Maronna, Maximiliano M., additional, Cigliano, María Marta, additional, Palacios-Gimenez, Octavio M., additional, Cabral-de-Mello, Diogo C., additional, and Martí, Dardo A., additional
- Published
- 2017
- Full Text
- View/download PDF
9. Contrasting the Chromosomal Organization of Repetitive DNAs in Two Gryllidae Crickets with Highly Divergent Karyotypes
- Author
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Carlos Roberto Ribeiro de Carvalho, Fernanda Aparecida Ferrari Soares, Octavio M. Palacios-Gimenez, Diogo Cavalcanti Cabral-de-Mello, Universidade Estadual Paulista (Unesp), and Universidade Federal de Viçosa (UFV)
- Subjects
Male ,medicine.medical_specialty ,Genome evolution ,Heterochromatin ,Genome, Insect ,Karyotype ,lcsh:Medicine ,Biology ,Chromosome organization of DNA ,Genome ,Evolution, Molecular ,Gryllidae ,Species Specificity ,medicine ,Animals ,Repeated sequence ,lcsh:Science ,Gene ,In Situ Hybridization, Fluorescence ,Repetitive Sequences, Nucleic Acid ,Genetics ,Multidisciplinary ,Sex Chromosomes ,lcsh:R ,Cytogenetics ,Chromosome Mapping ,Genetic Variation ,DNA ,Chromosomes, Insect ,Crickets ,Divergent karyotypes ,Karyotyping ,Multigene Family ,Microsatellite ,Female ,lcsh:Q ,Research Article - Abstract
Made available in DSpace on 2018-12-11T16:40:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-12-01 A large percentage of eukaryotic genomes consist of repetitive DNA that plays an important role in the organization, size and evolution. In the case of crickets, chromosomal variability has been found using classical cytogenetics, but almost no information concerning the organization of their repetitive DNAs is available. To better understand the chromosomal organization and diversification of repetitive DNAs in crickets, we studied the chromosomes of two Gryllidae species with highly divergent karyotypes, i.e., 2n(♂) = 29,X0 (Gryllus assimilis) and 2n = 9, neo-X1X2Y (Eneoptera surinamensis). The analyses were performed using classical cytogenetic techniques, repetitive DNA mapping and genome-size estimation. Conserved characteristics were observed, such as the occurrence of a small number of clusters of rDNAs and U snDNAs, in contrast to the multiple clusters/dispersal of the H3 histone genes. The positions of U2 snDNA and 18S rDNA are also conserved, being intermingled within the largest autosome. The distribution and base-pair composition of the heterochromatin and repetitive DNA pools of these organisms differed, suggesting reorganization. Although the microsatellite arrays had a similar distribution pattern, being dispersed along entire chromosomes, as has been observed in some grasshopper species, a band-like pattern was also observed in the E. surinamensis chromosomes, putatively due to their amplification and clustering. In addition to these differences, the genome of E. surinamensis is approximately 2.5 times larger than that of G. assimilis, which we hypothesize is due to the amplification of repetitive DNAs. Finally, we discuss the possible involvement of repetitive DNAs in the differentiation of the neo-sex chromosomes of E. surinamensis, as has been reported in other eukaryotic groups. This study provided an opportunity to explore the evolutionary dynamics of repetitive DNAs in two non-model species and will contribute to the understanding of chromosomal evolution in a group about which little chromosomal and genomic information is known. UNESP - Univ. Estadual Paulista Instituto de Biociências/IB Departamento de Biologia UFV-Univ. Federal de Viçosa Centro de Ciências Biológicas Departamento de Biologia Geral UNESP - Univ. Estadual Paulista Instituto de Biociências/IB Departamento de Biologia
- Published
- 2015
10. Polarity-Dependent Misperception of Subjective Visual Vertical during and after Transcranial Direct Current Stimulation (tDCS)
- Author
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Santos-Pontelli, Taiza E. G., primary, Rimoli, Brunna P., additional, Favoretto, Diandra B., additional, Mazin, Suleimy C., additional, Truong, Dennis Q., additional, Leite, Joao P., additional, Pontes-Neto, Octavio M., additional, Babyar, Suzanne R., additional, Reding, Michael, additional, Bikson, Marom, additional, and Edwards, Dylan J., additional
- Published
- 2016
- Full Text
- View/download PDF
11. Verticality Perceptions Associate with Postural Control and Functionality in Stroke Patients
- Author
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Baggio, Jussara A. O., primary, Mazin, Suleimy S. C., additional, Alessio-Alves, Frederico F., additional, Barros, Camila G. C., additional, Carneiro, Antonio A. O., additional, Leite, João P., additional, Pontes-Neto, Octavio M., additional, and Santos-Pontelli, Taiza E. G., additional
- Published
- 2016
- Full Text
- View/download PDF
12. A worldwide perspective on large carnivore attacks on humans
- Author
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Giulia Bombieri, Vincenzo Penteriani, Kamran Almasieh, Hüseyin Ambarlı, Mohammad Reza Ashrafzadeh, Chandan Surabhi Das, Nishith Dharaiya, Rafael Hoogesteijn, Almira Hoogesteijn, Dennis Ikanda, Włodzimierz Jędrzejewski, Mohammad Kaboli, Anastasia Kirilyuk, Ashish Kumar Jangid, Ravi Kumar Sharma, Hadas Kushnir, Babu Ram Lamichhane, Alireza Mohammadi, Octavio Monroy-Vilchis, Joseph M. Mukeka, Igor Nikolaev, Omar Ohrens, Craig Packer, Paolo Pedrini, Shyamala Ratnayeke, Ivan Seryodkin, Thomas Sharp, Himanshu Shekhar Palei, Tom Smith, Ashok Subedi, Fernando Tortato, Koji Yamazaki, and Maria del Mar Delgado
- Subjects
Biology (General) ,QH301-705.5 - Abstract
Large carnivores have long fascinated human societies and have profound influences on ecosystems. However, their conservation represents one of the greatest challenges of our time, particularly where attacks on humans occur. Where human recreational and/or livelihood activities overlap with large carnivore ranges, conflicts can become particularly serious. Two different scenarios are responsible for such overlap: In some regions of the world, increasing human populations lead to extended encroachment into large carnivore ranges, which are subject to increasing contraction, fragmentation, and degradation. In other regions, human and large carnivore populations are expanding, thus exacerbating conflicts, especially in those areas where these species were extirpated and are now returning. We thus face the problem of learning how to live with species that can pose serious threats to humans. We collected a total of 5,440 large carnivore (Felidae, Canidae, and Ursidae; 12 species) attacks worldwide between 1950 and 2019. The number of reported attacks increased over time, especially in lower-income countries. Most attacks (68%) resulted in human injuries, whereas 32% were fatal. Although attack scenarios varied greatly within and among species, as well as in different areas of the world, factors triggering large carnivore attacks on humans largely depend on the socioeconomic context, with people being at risk mainly during recreational activities in high-income countries and during livelihood activities in low-income countries. The specific combination of local socioeconomic and ecological factors is thus a risky mix triggering large carnivore attacks on humans, whose circumstances and frequencies cannot only be ascribed to the animal species. This also implies that effective measures to reduce large carnivore attacks must also consider the diverse local ecological and social contexts. A worldwide study of large carnivore attacks on people analyzes and compares the main patterns and circumstances within and among species and across geographic regions, shedding light on this complex and critical type of human-wildlife conflict.
- Published
- 2023
13. Infections and risk factors for infection-related mortality after pediatric allogeneic hematopoietic stem cell transplantation in Mexico: A single center retrospective study
- Author
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Elva Jiménez-Hernández, Juan Carlos Núñez-Enriquez, José Arellano-Galindo, María de los Angeles Del Campo-Martínez, Perla Verónica Reynoso-Arenas, Alfonso Reyes-López, Alejandra Viridiana Delgado-Gaytan, María Del Socorro Méndez-Tovar, Teresa Marín-Palomares, María Teresa Dueñas-Gonzalez, Antonio Ortíz-Fernández, Inés Montero-Ponce, Laura Eugenia Espinosa-Hernández, Nora Nancy Núñez-Villegas, Ruy Pérez-Casillas, Berenice Sánchez-Jara, Angel García-Soto, Annecy Nelly Herver-Olivares, Ethel Zulie Jaimes-Reyes, Hector Manuel Tiznado-García, Octavio Martínez-Villegas, Betzayda Valdez-Garibay, Paloma Del Rocío Loza-Santiaguillo, Xochiketzalli García-Jiménez, Guadalupe Ortíz-Torres, Gabriela Jazmin Fernández-Castillo, Dulce María Aguilar-Olivares, Luis Alejandro Díaz-Padilla, Mario Alberto Noya-Rodríguez, Mariana García-Jiménez, and Juan Manuel Mejía-Aranguré
- Subjects
Medicine ,Science - Published
- 2023
14. Chromosomal Mapping of Repetitive DNAs in the Grasshopper Abracris flavolineata Reveal Possible Ancestry of the B Chromosome and H3 Histone Spreading
- Author
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Danilo Bueno, Octavio M. Palacios-Gimenez, Diogo Cavalcanti Cabral-de-Mello, and Universidade Estadual Paulista (Unesp)
- Subjects
0106 biological sciences ,Male ,RNA 18S ,lcsh:Medicine ,animal cell ,01 natural sciences ,Histones ,histone H3 ,RNA, Small Nuclear ,chromosome variant ,genetic conservation ,lcsh:Science ,Genome Evolution ,In Situ Hybridization, Fluorescence ,chromosome map ,Genetics ,0303 health sciences ,telomere ,Multidisciplinary ,medicine.diagnostic_test ,chromosome analysis ,Chromosome Mapping ,Karyotype ,Genomics ,autosome ,RNA 5S ,Meiosis ,bioaccumulation ,female ,centromere ,Multigene Family ,Cytogenetic Analysis ,Female ,Research Article ,Satellite DNA ,DNA sequence ,satellite DNA ,Grasshoppers ,Biology ,RNA gene ,010603 evolutionary biology ,animal tissue ,03 medical and health sciences ,Cytogenetics ,male ,Centromere ,medicine ,RNA, Ribosomal, 18S ,Animals ,Abracris flavolineata ,Repeated sequence ,Small supernumerary marker chromosome ,fluorescence in situ hybridization ,030304 developmental biology ,Repetitive Sequences, Nucleic Acid ,B chromosome ,nonhuman ,DNA fragment ,repetitive DNA ,lcsh:R ,Computational Biology ,nucleotide sequence ,Chromosomes, Insect ,Caelifera ,karyotype ,plesiomorphy ,lcsh:Q ,Animal Genetics ,Fluorescence in situ hybridization - Abstract
Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:29:47Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:32:40Z : No. of bitstreams: 1 2-s2.0-84879540815.pdf: 1277537 bytes, checksum: 7617983d4fbd049e63eabc6061c45610 (MD5) Made available in DSpace on 2014-05-27T11:29:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-06-27 Supernumerary chromosomes (B chromosomes) occur in approximately 15% of eukaryote species. Although these chromosomes have been extensively studied, knowledge concerning their specific molecular composition is lacking in most cases. The accumulation of repetitive DNAs is one remarkable characteristic of B chromosomes, and the occurrence of distinct types of multigene families, satellite DNAs and some transposable elements have been reported. Here, we describe the organization of repetitive DNAs in the A complement and B chromosome system in the grasshopper species Abracris flavolineata using classical cytogenetic techniques and FISH analysis using probes for five multigene families, telomeric repeats and repetitive C0t-1 DNA fractions. The 18S rRNA and H3 histone multigene families are highly variable and well distributed in A. flavolineata chromosomes, which contrasts with the conservation of U snRNA genes and less variable distribution of 5S rDNA sequences. The H3 histone gene was an extensively distributed with clusters occurring in all chromosomes. Repetitive DNAs were concentrated in C-positive regions, including the pericentromeric region and small chromosomal arms, with some occurrence in C-negative regions, but abundance was low in the B chromosome. Finally, the first demonstration of the U2 snRNA gene in B chromosomes in A. flavolineata may shed light on its possible origin. These results provide new information regarding chromosomal variability for repetitive DNAs in grasshoppers and the specific molecular composition of B chromosomes. © 2013 Bueno et al. Universidade Estadual Paulista (UNESP) Instituto de Biociências/IB Departamento de Biologia, Rio Claro, São Paulo Universidade Estadual Paulista (UNESP) Instituto de Biociências/IB Departamento de Biologia, Rio Claro, São Paulo
- Published
- 2013
15. Verticality Perceptions Associate with Postural Control and Functionality in Stroke Patients
- Author
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João Pereira Leite, Antonio Adilton Oliveira Carneiro, Frederico F Alessio-Alves, Camila de Giacomo Carneiro Barros, Taiza E. G. Santos-Pontelli, Octavio M. Pontes-Neto, Jussara Almeida de Oliveira Baggio, and Suleimy Cristina Mazin
- Subjects
Male ,030506 rehabilitation ,Stroke patient ,INFARTO ,Social Sciences ,lcsh:Medicine ,Vascular Medicine ,Postural control ,Mathematical and Statistical Techniques ,0302 clinical medicine ,Medicine and Health Sciences ,Postural Balance ,Psychology ,lcsh:Science ,Stroke ,media_common ,Multidisciplinary ,Middle Aged ,Hemorrhagic Stroke ,Neurology ,Physical Sciences ,Sensation Disorders ,Regression Analysis ,Sensory Perception ,Female ,Anatomy ,0305 other medical science ,Statistics (Mathematics) ,Research Article ,medicine.medical_specialty ,Cognitive Neuroscience ,Cerebrovascular Diseases ,media_common.quotation_subject ,Posture ,Linear Regression Analysis ,Research and Analysis Methods ,Sitting ,Standing Positions ,Motor Reactions ,03 medical and health sciences ,Physical medicine and rehabilitation ,Ocular System ,Perception ,medicine ,Humans ,Statistical Methods ,Ischemic Stroke ,Aged ,Balance and Falls ,business.industry ,lcsh:R ,Posturography ,Biology and Life Sciences ,medicine.disease ,Postural Control ,Geriatrics ,Space Perception ,Physical therapy ,Eyes ,Cognitive Science ,lcsh:Q ,business ,Head ,Mathematics ,030217 neurology & neurosurgery ,Neuroscience - Abstract
Deficits of postural control and perceptions of verticality are disabling problems observed in stroke patients that have been recently correlated to each other. However, there is no evidence in the literature confirming this relationship with quantitative posturography analysis. Therefore, the objectives of the present study were to analyze the relationship between Subjective Postural Vertical (SPV) and Haptic Vertical (HV) with posturography and functionality in stroke patients. We included 45 stroke patients. The study protocol was composed by clinical interview, evaluation of SPV and HV in roll and pitch planes and posturography. Posturography was measured in the sitting and standing positions under the conditions: eyes open, stable surface (EOSS); eyes closed, stable surface (ECSS); eyes open, unstable surface (EOUS); and eyes closed, unstable surface (ECUS). The median PV in roll plane was 0.34° (-1.44° to 2.54°) and in pitch plane 0.36° (-2.72° to 2.45°). The median of HV in roll and pitch planes were -0.94° (-5.86° to 3.84°) and 3.56° (-0.68° to 8.36°), respectively. SPV in the roll plane was correlated with all posturagraphy parameters in sitting position in all conditions (r = 0.35 to 0.47; p < 0.006). There were moderate correlations with the verticality perceptions and all the functional scales. Linear regression model showed association between speed and SPV in the roll plane in the condition EOSS (R2 of 0.37; p = 0.005), in the condition ECSS (R2 of 0.13; p = 0.04) and in the condition EOUS (R2 of 0.22; p = 0.03). These results suggest that verticality perception is a relevant component of postural control and should be systematically evaluated, particularly in patients with abnormal postural control.
- Published
- 2016
- Full Text
- View/download PDF
16. Contrasting the Chromosomal Organization of Repetitive DNAs in Two Gryllidae Crickets with Highly Divergent Karyotypes
- Author
-
Palacios-Gimenez, Octavio M., primary, Carvalho, Carlos Roberto, additional, Ferrari Soares, Fernanda Aparecida, additional, and Cabral-de-Mello, Diogo C., additional
- Published
- 2015
- Full Text
- View/download PDF
17. Heme Oxygenase-1 Protects Corexit 9500A-Induced Respiratory Epithelial Injury across Species
- Author
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Li, Fu Jun, primary, Duggal, Ryan N., additional, Oliva, Octavio M., additional, Karki, Suman, additional, Surolia, Ranu, additional, Wang, Zheng, additional, Watson, R. Douglas, additional, Thannickal, Victor J., additional, Powell, Mickie, additional, Watts, Stephen, additional, Kulkarni, Tejaswini, additional, Batra, Hitesh, additional, Bolisetty, Subhashini, additional, Agarwal, Anupam, additional, and Antony, Veena B., additional
- Published
- 2015
- Full Text
- View/download PDF
18. A new theropod dinosaur from the early cretaceous (Barremian) of Cabo Espichel, Portugal: Implications for spinosaurid evolution.
- Author
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Octávio Mateus and Darío Estraviz-López
- Subjects
Medicine ,Science - Abstract
Spinosaurids are some of the most enigmatic Mesozoic theropod dinosaurs due to their unique adaptations to aquatic environments and their relative scarcity. Their taxonomy has proven to be especially problematic. Recent discoveries from Western Europe in general, specifically Iberia, provide some of the best specimens for the understanding of their phylogeny, leading to the description of the spinosaurid Vallibonavenatrix cani and the recognition of the Iberian dinosaur Camarillasaurus cirugedae as one of them. Portuguese associated spinosaurid remains (ML1190) from the Papo Seco Formation (early Barremian) were previously assigned to Baryonyx walkeri but new material recovered in 2020 along with new phylogenetic analyses suggests a different phylogenetic placement, making their revision necessary. Here we show that these remains are not attributable to Baryonyx walkeri, but to a new genus and species, Iberospinus natarioi, gen. et sp. nov. The new taxon is characterized by the presence of a single Meckelian foramen in the Meckelian sulcus, a straight profile of the ventral surface of the dentary and a distal thickening of the acromion process of the pubis between other characters. Iberospinus natarioi is recovered as a sister taxon of the clade formed by Baryonyx and Suchomimus, and outside Spinosaurinae when Vallibonaventrix cani is excluded from the analysis. The description of this taxon reinforces Iberia as a hotspot for spinosaur biodiversity, with several endemic taxa for the region. As expected for the clade, the dentary displays a highly vascularized neurovascular network. The morphometric analysis of parts of the skeleton (pedal phalanx and caudal vertebrae, among others) shows an intermediate condition between basal tetanurans and spinosaurines.
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- 2022
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19. Genomic heterogeneity underlies multidrug resistance in Pseudomonas aeruginosa: A population-level analysis beyond susceptibility testing.
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Laura J Rojas, Mohamad Yasmin, Jacquelynn Benjamino, Steven M Marshall, Kailynn J DeRonde, Nikhil P Krishnan, Federico Perez, Andrew A Colin, Monica Cardenas, Octavio Martinez, Armando Pérez-Cardona, Daniel D Rhoads, Michael R Jacobs, John J LiPuma, Michael W Konstan, Alejandro J Vila, Andrea Smania, Andrew R Mack, Jacob G Scott, Mark D Adams, Lilian M Abbo, and Robert A Bonomo
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Medicine ,Science - Abstract
BackgroundPseudomonas aeruginosa is a persistent and difficult-to-treat pathogen in many patients, especially those with Cystic Fibrosis (CF). Herein, we describe a longitudinal analysis of a series of multidrug resistant (MDR) P. aeruginosa isolates recovered in a 17-month period, from a young female CF patient who underwent double lung transplantation. Our goal was to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence evolution over time.MethodsTwenty-two sequential P. aeruginosa isolates were obtained within a 17-month period, before and after a double-lung transplant. At the end of the study period, antimicrobial susceptibility testing, whole genome sequencing (WGS), phylogenetic analyses and RNAseq were performed in order to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence changes over time.ResultsThe majority of isolates were resistant to almost all tested antibiotics. A phylogenetic reconstruction revealed 3 major clades representing a genotypically and phenotypically heterogeneous population. The pattern of mutation accumulation and variation of gene expression suggested that a group of closely related strains was present in the patient prior to transplantation and continued to change throughout the course of treatment. A trend toward accumulation of mutations over time was observed. Different mutations in the DNA mismatch repair gene mutL consistent with a hypermutator phenotype were observed in two clades. RNAseq performed on 12 representative isolates revealed substantial differences in the expression of genes associated with antibiotic resistance and virulence traits.ConclusionsThe overwhelming current practice in the clinical laboratories setting relies on obtaining a pure culture and reporting the antibiogram from a few isolated colonies to inform therapy decisions. Our analyses revealed significant underlying genomic heterogeneity and unpredictable evolutionary patterns that were independent of prior antibiotic treatment, highlighting the need for comprehensive sampling and population-level analysis when gathering microbiological data in the context of CF P. aeruginosa chronic infection. Our findings challenge the applicability of antimicrobial stewardship programs based on single-isolate resistance profiles for the selection of antibiotic regimens in chronic infections such as CF.
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- 2022
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20. Transcriptomic analysis of a wild and a cultivated varieties of Capsicum annuum over fruit development and ripening.
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Fernando G Razo-Mendivil, Fernando Hernandez-Godínez, Corina Hayano-Kanashiro, and Octavio Martínez
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Medicine ,Science - Abstract
Chili pepper (Capsicum annuum) is one of the most important crops worldwide. Its fruits contain metabolites produced over the maturation process like capsaicinoids and carotenoids. This metabolic process produces internal changes in flavor, color, texture, and aroma in fruits to make them more attractive for seed dispersal organisms. The chiltepin (C. annuum L. var. glabriusculum) is a wild variety of the C. annuum L. species that is considered a source of genetic resources that could be used to improve the current chili crops. In this study, we performed a transcriptomic analysis on two fruit maturation stages: immature stage (green fruit) and mature stage (red fruit) of a wild and a cultivated pepper variety. We found 19,811 genes expressed, and 1,008 genes differentially expressed (DEGs) in at least one of the five contrast used; 730 DEGs were found only in one contrast, and most DEGs in all contrasts were downregulated. GO enrichment analysis showed that the majority of DEGs are related to stress responses. KEGG enrichment analysis detected differences in expression patterns in metabolic pathways related to phenylpropanoid biosynthesis, secondary metabolites, plant hormone signal transduction, carotenoid biosynthesis and sesquiterpenoid and triterpenoid biosynthesis. We selected 105 tomato fruit ripening-related genes, and found 53 pepper homologs differentially expressed related to shape, size, and secondary metabolite biosynthesis. According to the transcriptome analysis, the two peppers showed very similar gene expression patterns; differences in expression patterns of genes related to shape, size, ethylene and secondary metabolites biosynthesis suggest that changes produced by domestication of chilli pepper could be very specific to the expression of genes related to traits desired in commercial fruits.
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- 2021
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21. Osteology of an exceptionally well-preserved tapejarid skeleton from Brazil: Revealing the anatomy of a curious pterodactyloid clade.
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Victor Beccari, Felipe Lima Pinheiro, Ivan Nunes, Luiz Eduardo Anelli, Octávio Mateus, and Fabiana Rodrigues Costa
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Medicine ,Science - Abstract
A remarkably well-preserved, almost complete and articulated new specimen (GP/2E 9266) of Tupandactylus navigans is here described for the Early Cretaceous Crato Formation of Brazil. The new specimen comprises an almost complete skeleton, preserving both the skull and post-cranium, associated with remarkable preservation of soft tissues, which makes it the most complete tapejarid known thus far. CT-Scanning was performed to allow the assessment of bones still covered by sediment. The specimen can be assigned to Tupa. navigans due to its vertical supra-premaxillary bony process and short and rounded parietal crest. It also bears the largest dentary crest among tapejarine pterosaurs and a notarium, which is absent in other representatives of the clade. The new specimen is here regarded as an adult individual. This is the first time that postcranial remains of Tupa. navigans are described, being also an unprecedented record of an articulated tapejarid skeleton from the Araripe Basin.
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- 2021
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22. Transcriptomic analysis reveals key transcription factors associated to drought tolerance in a wild papaya (Carica papaya) genotype.
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Humberto Estrella-Maldonado, Amaranta Girón Ramírez, Gabriela Fuentes Ortiz, Santy Peraza-Echeverría, Octavio Martínez-de la Vega, Elsa Góngora-Castillo, and Jorge M Santamaría
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Medicine ,Science - Abstract
Most of the commercial papaya genotypes show susceptibility to water deficit stress and require high volumes of irrigation water to yield properly. To tackle this problem, we have collected wild native genotypes of Carica papaya that have proved to show better physiological performance under water deficit stress than the commercial cultivar grown in Mexico. In the present study, plants from a wild Carica papaya genotype and a commercial genotype were subjected to water deficit stress (WDS), and their response was characterized in physiological and molecular terms. The physiological parameters measured (water potential, photosynthesis, Fv/Fm and electrolyte leakage) confirmed that the papaya wild genotype showed better physiological responses than the commercial one when exposed to WDS. Subsequently, RNA-Seq was performed for 4 cDNA libraries in both genotypes (susceptible and tolerant) under well-watered conditions, and when they were subjected to WDS for 14 days. Consistently, differential expression analysis revealed that after 14 days of WDS, the wild tolerant genotype had a higher number of up-regulated genes, and a higher number of transcription factors (TF) that were differentially expressed in response to WDS, than the commercial genotype. Thus, six TF genes (CpHSF, CpMYB, CpNAC, CpNFY-A, CpERF and CpWRKY) were selected for further qRT-PCR analysis as they were highly expressed in response to WDS in the wild papaya genotype. qRT-PCR results confirmed that the wild genotype had higher expression levels (REL) in all 6 TF genes than the commercial genotype. Our transcriptomic analysis should help to unravel candidate genes that may be useful in the development of new drought-tolerant cultivars of this important tropical crop.
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- 2021
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23. The cranial anatomy and relationships of Cardiocorax mukulu (Plesiosauria: Elasmosauridae) from Bentiaba, Angola.
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Miguel P Marx, Octávio Mateus, Michael J Polcyn, Anne S Schulp, A Olímpio Gonçalves, and Louis L Jacobs
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Medicine ,Science - Abstract
We report a new specimen of the plesiosaur Cardiocorax mukulu that includes the most complete plesiosaur skull from sub-Saharan Africa. The well-preserved three-dimensional nature of the skull offers rare insight into the cranial anatomy of elasmosaurid plesiosaurians. The new specimen of Cardiocorax mukulu was recovered from Bentiaba, Namibe Province in Angola, approximately three meters above the holotype. The new specimen also includes an atlas-axis complex, seventeen postaxial cervical vertebrae, partial ribs, a femur, and limb elements. It is identified as Cardiocorax mukulu based on an apomorphy shared with the holotype where the cervical neural spine is approximately as long anteroposteriorly as the centrum and exhibits a sinusoidal anterior margin. The new specimen is nearly identical to the holotype and previously referred material in all other aspects. Cardiocorax mukulu is returned in an early-branching or intermediate position in Elasmosauridae in four out of the six of our phylogenetic analyses. Cardiocorax mukulu lacks the elongated cervical vertebrae that is characteristic of the extremely long-necked elasmosaurines, and the broad skull with and a high number of maxillary teeth (28-40) which is characteristic of Aristonectinae. Currently, the most parsimonious explanation concerning elasmosaurid evolutionary relationships, is that Cardiocorax mukulu represents an older lineage of elasmosaurids in the Maastrichtian.
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- 2021
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24. Phenotypical antimicrobial resistance data of clinical and non-clinical Escherichia coli from poultry in Germany between 2014 and 2017.
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Octavio Mesa-Varona, Heike Kaspar, Mirjam Grobbel, and Bernd-Alois Tenhagen
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Medicine ,Science - Abstract
Antimicrobial resistance (AMR) is a global threat in humans and animals, and antimicrobial usage (AMU) has been identified as a main trigger of AMR. The purpose of this work was to compare data on AMR in clinical and non-clinical isolates of Escherichia coli in German broilers and turkeys between 2014 and 2017. Furthermore, we investigated AMR changes over time and the association of changes in AMU with changes in AMR. Data on clinical and non-clinical isolates together with data on therapy frequency of broilers and turkeys were collected from German monitoring systems. Logistic regression analyses were performed to assess the association between the explanatory factors (AMU, year and isolate type) and the dependent variable (AMR). In broilers, the analysis showed lower resistance proportions of clinical isolates of E. coli to ampicillin and colistin (ampicillin: Odds ratio (OR) and 95% confidence interval (CI) = 0.44 (0.3-0.64), p
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- 2020
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25. Using graph learning to understand adverse pregnancy outcomes and stress pathways.
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Octavio Mesner, Alex Davis, Elizabeth Casman, Hyagriv Simhan, Cosma Shalizi, Lauren Keenan-Devlin, Ann Borders, and Tamar Krishnamurti
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Medicine ,Science - Abstract
To identify pathways between stress indicators and adverse pregnancy outcomes, we applied a nonparametric graph-learning algorithm, PC-KCI, to data from an observational prospective cohort study. The Measurement of Maternal Stress study (MOMS) followed 744 women with a singleton intrauterine pregnancy recruited between June 2013 and May 2015. Infant adverse pregnancy outcomes were prematurity (
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- 2019
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26. Dacentrurine stegosaurs (Dinosauria): A new specimen of Miragaia longicollum from the Late Jurassic of Portugal resolves taxonomical validity and shows the occurrence of the clade in North America.
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Francisco Costa and Octávio Mateus
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Medicine ,Science - Abstract
The stegosaur species Miragaia longicollum was erected based on a partial anterior skeleton from the Upper Jurassic of Portugal. Until then, almost all stegosaur specimens in Portugal and Spain had been identified as Dacentrurus armatus, the sister taxon of M. longicollum and only other member of the clade Dacentrurinae. The holotypes of the two species have little overlap, since the holotype of D. armatus is mostly a posterior skeleton, so the classification of other specimens to either species is unclear and the validity of M. longicollum has been questioned and debated. Here we describe a largely complete specimen of M. longicollum discovered in 1959 in Atouguia da Baleia, Peniche, Portugal, consisting of both anterior and posterior portions of the skeleton. Comparisons to the holotypes of dacentrurines and other stegosaurs shed light on the convoluted relationships of this group. We conclude that M. longicollum is valid and rather different from D. armatus, and provide a revised diagnosis of M. longicollum, as well as revised diagnoses for D. armatus, Dacentrurinae, and the first diagnosis of the genus Miragaia, granting stability to these taxa and allowing new considerations to be given on the classification of other Iberian stegosaurs. This new specimen is, to date, the most complete dinosaur described from Portugal and the most complete stegosaur described from Europe. Miragaia shared anatomical features that show a close affinity to Alcovasaurus longispinus, confirming this to be the first known dacentrurine stegosaur in America, coherent with the hypothesis of an ephemeral land bridge between North America and Iberia that allowed faunal exchange.
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- 2019
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27. On an algorithmic definition for the components of the minimal cell.
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Octavio Martínez and M Humberto Reyes-Valdés
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Medicine ,Science - Abstract
Living cells are highly complex systems comprising a multitude of elements that are engaged in the many convoluted processes observed during the cell cycle. However, not all elements and processes are essential for cell survival and reproduction under steady-state environmental conditions. To distinguish between essential from expendable cell components and thus define the 'minimal cell' and the corresponding 'minimal genome', we postulate that the synthesis of all cell elements can be represented as a finite set of binary operators, and within this framework we show that cell elements that depend on their previous existence to be synthesized are those that are essential for cell survival. An algorithm to distinguish essential cell elements is presented and demonstrated within an interactome. Data and functions implementing the algorithm are given as supporting information. We expect that this algorithmic approach will lead to the determination of the complete interactome of the minimal cell, which could then be experimentally validated. The assumptions behind this hypothesis as well as its consequences for experimental and theoretical biology are discussed.
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- 2018
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28. Lévy foraging patterns of rural humans.
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Andy Reynolds, Eliane Ceccon, Cristina Baldauf, Tassia Karina Medeiros, and Octavio Miramontes
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Medicine ,Science - Abstract
Movement patterns resembling Lévy walks, often attributed to the execution of an advantageous probabilistic searching strategy, are found in a wide variety of organisms, from cells to human hunter-gatherers. It has been suggested that such movement patterns may be fundamental to how humans interact and experience the world and that they may have arisen early in our genus with the evolution of a hunting and gathering lifestyle. Here we show that Lévy walks are evident in the Me'Phaa of Mexico, in Brazilian Cariri farmers and in Amazonian farmers when gathering firewood, wild fruit and nuts. Around 50% of the search patterns resemble Lévy walks and these are characterized by Lévy exponents close to 1.7. The other search patterns more closely resemble bi-phasic walks. We suggest potential generative mechanisms for the occurrence of these ubiquitous Lévy walks which can be used to guide future studies on human mobility. We show that frequent excursions and meanderings from pre-existing trails can account for our observations.
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- 2018
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29. The Ferric uptake regulator (Fur) and iron availability control the production and maturation of the antibacterial peptide microcin E492.
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Andrés E Marcoleta, Sergio Gutiérrez-Cortez, Felipe Hurtado, Yerko Argandoña, Gino Corsini, Octavio Monasterio, and Rosalba Lagos
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Medicine ,Science - Abstract
Microcin E492 is a pore-forming bacteriocin with toxic activity against Enterobacteriaceae, which undergoes amyloid aggregation as a mechanism to regulate its toxicity. To be active, it requires the posttranslational attachment to the C-terminus of a glycosylated enterochelin derivative (salmochelin), a process carried out by the proteins MceC, MceI and MceJ encoded in the MccE492 gene cluster. Both microcin E492 and salmochelin have a proposed role in the virulence of the bacterial pathogen Klebsiella pneumoniae. Besides, enterochelin is produced as a response to low iron availability and its synthesis is controlled by the global iron regulator Fur. Since the production of active microcin E492 depends on enterochelin biosynthesis, both processes could be coordinately regulated. In this work, we investigated the role of Fur in the expression of the microcin E492 maturation genes mceCJI. mceC was not regulated by Fur as it occurs with its homolog iroB in Salmonella enterica. We demonstrated that mceJI along with the previously uncharacterized gene mceX are transcribed as a single mRNA, and that Fur binds in vivo to a Fur box located upstream of the mceX-mceJI unit. Also, we established that the expression of these genes decreased in a condition of high iron availability, while this effect is abrogated in a Δfur background. Furthermore, our results indicated that MceX acts as a negative regulator of microcin E492 structural gene expression, coupling its synthesis to the iron-dependent regulatory circuit. Consequently, fur or mceX overexpression led to a significant decrease in the antibacterial activity of cells producing microcin E492. Altogether these results show that both the expression of microcin E492 maturation genes mceJI, and MceX the negative regulator of microcin E492 synthesis, are coordinated with the enterochelin production by Fur, depending on the iron levels in the medium.
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- 2018
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30. An informational view of accession rarity and allele specificity in germplasm banks for management and conservation.
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M Humberto Reyes-Valdés, Juan Burgueño, Sukhwinder Singh, Octavio Martínez, and Carolina Paola Sansaloni
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Medicine ,Science - Abstract
Germplasm banks are growing in their importance, number of accessions and amount of characterization data, with a large emphasis on molecular genetic markers. In this work, we offer an integrated view of accessions and marker data in an information theory framework. The basis of this development is the mutual information between accessions and allele frequencies for molecular marker loci, which can be decomposed in allele specificities, as well as in rarity and divergence of accessions. In this way, formulas are provided to calculate the specificity of the different marker alleles with reference to their distribution across accessions, accession rarity, defined as the weighted average of the specificity of its alleles, and divergence, defined by the Kullback-Leibler formula. Albeit being different measures, it is demonstrated that average rarity and divergence are equal for any collection. These parameters can contribute to the knowledge of the structure of a germplasm collection and to make decisions about the preservation of rare variants. The concepts herein developed served as the basis for a strategy for core subset selection called HCore, implemented in a publicly available R script. As a proof of concept, the mathematical view and tools developed in this research were applied to a large collection of Mexican wheat accessions, widely characterized by SNP markers. The most specific alleles were found to be private of a single accession, and the distribution of this parameter had its highest frequencies at low levels of specificity. Accession rarity and divergence had largely symmetrical distributions, and had a positive, albeit non-strictly linear relationship. Comparison of the HCore approach for core subset selection, with three state-of-the-art methods, showed it to be superior for average divergence and rarity, mean genetic distance and diversity. The proposed approach can be used for knowledge extraction and decision making in germplasm collections of diploid, inbred or outbred species.
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- 2018
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31. Thermal adaptation of mesophilic and thermophilic FtsZ assembly by modulation of the critical concentration.
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Luis Concha-Marambio, Paula Maldonado, Rosalba Lagos, Octavio Monasterio, and Felipe Montecinos-Franjola
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Medicine ,Science - Abstract
Cytokinesis is the last stage in the cell cycle. In prokaryotes, the protein FtsZ guides cell constriction by assembling into a contractile ring-shaped structure termed the Z-ring. Constriction of the Z-ring is driven by the GTPase activity of FtsZ that overcomes the energetic barrier between two protein conformations having different propensities to assemble into polymers. FtsZ is found in psychrophilic, mesophilic and thermophilic organisms thereby functioning at temperatures ranging from subzero to >100°C. To gain insight into the functional adaptations enabling assembly of FtsZ in distinct environmental conditions, we analyzed the energetics of FtsZ function from mesophilic Escherichia coli in comparison with FtsZ from thermophilic Methanocaldococcus jannaschii. Presumably, the assembly may be similarly modulated by temperature for both FtsZ orthologs. The temperature dependence of the first-order rates of nucleotide hydrolysis and of polymer disassembly, indicated an entropy-driven destabilization of the FtsZ-GTP intermediate. This destabilization was true for both mesophilic and thermophilic FtsZ, reflecting a conserved mechanism of disassembly. From the temperature dependence of the critical concentrations for polymerization, we detected a change of opposite sign in the heat capacity, that was partially explained by the specific changes in the solvent-accessible surface area between the free and polymerized states of FtsZ. At the physiological temperature, the assembly of both FtsZ orthologs was found to be driven by a small positive entropy. In contrast, the assembly occurred with a negative enthalpy for mesophilic FtsZ and with a positive enthalpy for thermophilic FtsZ. Notably, the assembly of both FtsZ orthologs is characterized by a critical concentration of similar value (1-2 μM) at the environmental temperatures of their host organisms. These findings suggest a simple but robust mechanism of adaptation of FtsZ, previously shown for eukaryotic tubulin, by adjustment of the critical concentration for polymerization.
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- 2017
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32. Two new ootaxa from the late Jurassic: The oldest record of crocodylomorph eggs, from the Lourinhã Formation, Portugal.
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João Russo, Octávio Mateus, Marco Marzola, and Ausenda Balbino
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Medicine ,Science - Abstract
The Late Jurassic Lourinhã Formation is known for its abundant remains of dinosaurs, crocodylomorphs and other vertebrates. Among this record are nine localities that have produced either dinosaur embryos, eggs or eggshell fragments. Herein, we describe and identify the first crocodiloid morphotype eggs and eggshells from the Lourinhã Formation, from five occurrences. One clutch from Cambelas, composed of 13 eggs, eggshell fragments from Casal da Rola and Peralta, one crushed egg and eggshells from Paimogo North, and four crushed eggs as well as eggshell fragments from Paimogo South. We observed and confirmed diagnostic morphological characters for crocodiloid eggshells and which are consistent with a crocodylomorph affinity, such as the ellipsoidal shape, wedge-shaped shell units, triangular extinction under cross-polarized light, and tabular ultrastructure. This material is distinctive enough to propose two new ootaxa within the oofamily Krokolithidae, Suchoolithus portucalensis, oogen. and oosp. nov., for the material from Cambelas, the most complete clutch known for crocodiloid eggs, and Krokolithes dinophilus, oosp. nov., for the remaining material. These are the oldest crocodylomorph eggs known, extending the fossil record for this group to the Late Jurassic. Furthermore, except for the clutch from Cambelas, the material was found with theropod eggs and nests, in the other four occurrences, which seem to suggest some form of biological relationship, still unclear at this point.
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- 2017
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33. Epidemiological, clinical, diagnostic and economic features of an immigrant population of chronic schistosomiasis sufferers with long-term residence in a non-endemic country (North Metropolitan area of Barcelona, 2002-2016).
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Sílvia Roure, Lluís Valerio, Olga Pérez-Quílez, Gema Fernández-Rivas, Octavio Martínez-Cuevas, Albert Alcántara-Román, Diego Viasus, M Luisa Pedro-Botet, Miquel Sabrià, and Bonaventura Clotet
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Medicine ,Science - Abstract
Schistosomiasis, one of the neglected tropical diseases (NTD) listed by the WHO, is an acute and chronic parasitic disease caused by blood flukes (trematode worms) of the genus Schistosoma. Complications of long-term infestation include liver cirrhosis, bladder tumors and kidney failure. The objective of this study was to carry out a clinical and epidemiological characterization of a schistosomiasis-diagnosed immigrant population with long-term residencein the EU as well as to evaluate the diagnostic methods available to date.A total of 61 individuals with Schistosoma infection who received medical attention between June 2002 and June 2016 at the North Metropolitan International Health Unit in Barcelona (Catalonia, Spain), were included in the study. All patients were sub-Saharan African immigrants. The majority were male (91.8%) with a median age of 34 years. Symptoms attributable to infection such as haematuria, abdominal pain and dysuria were recorded in up to 90% of patients. The percentage of eosinophils decreased amongst older patients (p = 0.002) and those with symptoms associated with urinary tract infections (p = 0.017). Serology was used for diagnosis in 80.3% of the cases, with microscopic examination showing the remaining 9.8% positive for parasite eggs. Direct microbiological diagnosis was more useful in patients with less than 5 years of residence in the EU (p = 0.05). Chronic complications were present in 22 (36%) of the patients, with renal failure affecting 20 (33%). Of these 20, 6(10%) developed terminal renal failure and required hemodialysis, while 3 (5%) received a renal transplantation.Morbidity associated with chronic long-term schistosomiasis is frequent among African immigrants in non-endemic countries. Better diagnostic tools and appropriate early treatment would prevent the development of visceral damage. Thorough screening in selected patients would also be useful to avoid chronic complications.
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- 2017
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34. Inhibition of the Hantavirus Fusion Process by Predicted Domain III and Stem Peptides from Glycoprotein Gc.
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Gonzalo P Barriga, Fernando Villalón-Letelier, Chantal L Márquez, Eduardo A Bignon, Rodrigo Acuña, Breyan H Ross, Octavio Monasterio, Gonzalo A Mardones, Simon E Vidal, and Nicole D Tischler
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
Hantaviruses can cause hantavirus pulmonary syndrome or hemorrhagic fever with renal syndrome in humans. To enter cells, hantaviruses fuse their envelope membrane with host cell membranes. Previously, we have shown that the Gc envelope glycoprotein is the viral fusion protein sharing characteristics with class II fusion proteins. The ectodomain of class II fusion proteins is composed of three domains connected by a stem region to a transmembrane anchor in the viral envelope. These fusion proteins can be inhibited through exogenous fusion protein fragments spanning domain III (DIII) and the stem region. Such fragments are thought to interact with the core of the fusion protein trimer during the transition from its pre-fusion to its post-fusion conformation. Based on our previous homology model structure for Gc from Andes hantavirus (ANDV), here we predicted and generated recombinant DIII and stem peptides to test whether these fragments inhibit hantavirus membrane fusion and cell entry. Recombinant ANDV DIII was soluble, presented disulfide bridges and beta-sheet secondary structure, supporting the in silico model. Using DIII and the C-terminal part of the stem region, the infection of cells by ANDV was blocked up to 60% when fusion of ANDV occurred within the endosomal route, and up to 95% when fusion occurred with the plasma membrane. Furthermore, the fragments impaired ANDV glycoprotein-mediated cell-cell fusion, and cross-inhibited the fusion mediated by the glycoproteins from Puumala virus (PUUV). The Gc fragments interfered in ANDV cell entry by preventing membrane hemifusion and pore formation, retaining Gc in a non-resistant homotrimer stage, as described for DIII and stem peptide inhibitors of class II fusion proteins. Collectively, our results demonstrate that hantavirus Gc shares not only structural, but also mechanistic similarity with class II viral fusion proteins, and will hopefully help in developing novel therapeutic strategies against hantaviruses.
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- 2016
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35. The Association between Sexually Transmitted Infections, Length of Service and Other Demographic Factors in the U.S. Military.
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Robert Deiss, Richard J Bower, Edgie Co, Octavio Mesner, Jose L Sanchez, Jennifer Masel, Anuradha Ganesan, Grace E Macalino, and Brian K Agan
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Medicine ,Science - Abstract
Numerous studies have found higher rates of sexually transmitted infections (STIs) among military personnel than the general population, but the cumulative risk of acquiring STIs throughout an individual's military career has not been described.Using ICD-9 diagnosis codes, we analyzed the medical records of 100,005 individuals from all service branches, divided in equal cohorts (n = 6,667) between 1997 and 2011. As women receive frequent STI screening compared to men, these groups were analyzed separately. Incidence rates were calculated for pathogen-specific STIs along with syndromic diagnoses. Descriptive statistics were used to characterize the individuals within each accession year cohort; repeat infections were censored.The total sample included 29,010 females and 70,995 males. The STI incidence rates (per 100 person-years) for women and men, respectively, were as follows: chlamydia (3.5 and 0.7), gonorrhea (1.1 and 0.4), HIV (0.04 and 0.07) and syphilis (0.14 and 0.15). During the study period, 22% of women and 3.3% of men received a pathogen-specific STI diagnosis; inclusion of syndromic diagnoses increased STI prevalence to 41% and 5.5%, respectively. In multivariate analyses, factors associated with etiologic and syndromic STIs among women included African American race, younger age and fewer years of education. In the overall sample, increasing number of years of service was associated with an increased likelihood of an STI diagnosis (p
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- 2016
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36. Morphofunctional Analysis of the Quadrate of Spinosauridae (Dinosauria: Theropoda) and the Presence of Spinosaurus and a Second Spinosaurine Taxon in the Cenomanian of North Africa.
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Christophe Hendrickx, Octávio Mateus, and Eric Buffetaut
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Medicine ,Science - Abstract
Six quadrate bones, of which two almost certainly come from the Kem Kem beds (Cenomanian, Upper Cretaceous) of south-eastern Morocco, are determined to be from juvenile and adult individuals of Spinosaurinae based on phylogenetic, geometric morphometric, and phylogenetic morphometric analyses. Their morphology indicates two morphotypes evidencing the presence of two spinosaurine taxa ascribed to Spinosaurus aegyptiacus and? Sigilmassasaurus brevicollis in the Cenomanian of North Africa, casting doubt on the accuracy of some recent skeletal reconstructions which may be based on elements from several distinct species. Morphofunctional analysis of the mandibular articulation of the quadrate has shown that the jaw mechanics was peculiar in Spinosauridae. In mature spinosaurids, the posterior parts of the two mandibular rami displaced laterally when the jaw was depressed due to a lateromedially oriented intercondylar sulcus of the quadrate. Such lateral movement of the mandibular ramus was possible due to a movable mandibular symphysis in spinosaurids, allowing the pharynx to be widened. Similar jaw mechanics also occur in some pterosaurs and living pelecanids which are both adapted to capture and swallow large prey items. Spinosauridae, which were engaged, at least partially, in a piscivorous lifestyle, were able to consume large fish and may have occasionally fed on other prey such as pterosaurs and juvenile dinosaurs.
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- 2016
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37. Tremor Detection Using Parametric and Non-Parametric Spectral Estimation Methods: A Comparison with Clinical Assessment.
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Octavio Martinez Manzanera, Jan Willem Elting, Johannes H van der Hoeven, and Natasha M Maurits
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Medicine ,Science - Abstract
In the clinic, tremor is diagnosed during a time-limited process in which patients are observed and the characteristics of tremor are visually assessed. For some tremor disorders, a more detailed analysis of these characteristics is needed. Accelerometry and electromyography can be used to obtain a better insight into tremor. Typically, routine clinical assessment of accelerometry and electromyography data involves visual inspection by clinicians and occasionally computational analysis to obtain objective characteristics of tremor. However, for some tremor disorders these characteristics may be different during daily activity. This variability in presentation between the clinic and daily life makes a differential diagnosis more difficult. A long-term recording of tremor by accelerometry and/or electromyography in the home environment could help to give a better insight into the tremor disorder. However, an evaluation of such recordings using routine clinical standards would take too much time. We evaluated a range of techniques that automatically detect tremor segments in accelerometer data, as accelerometer data is more easily obtained in the home environment than electromyography data. Time can be saved if clinicians only have to evaluate the tremor characteristics of segments that have been automatically detected in longer daily activity recordings. We tested four non-parametric methods and five parametric methods on clinical accelerometer data from 14 patients with different tremor disorders. The consensus between two clinicians regarding the presence or absence of tremor on 3943 segments of accelerometer data was employed as reference. The nine methods were tested against this reference to identify their optimal parameters. Non-parametric methods generally performed better than parametric methods on our dataset when optimal parameters were used. However, one parametric method, employing the high frequency content of the tremor bandwidth under consideration (High Freq) performed similarly to non-parametric methods, but had the highest recall values, suggesting that this method could be employed for automatic tremor detection.
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- 2016
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38. Bacterial Vaginosis Is Associated with Loss of Gamma Delta T Cells in the Female Reproductive Tract in Women in the Miami Women Interagency HIV Study (WIHS): A Cross Sectional Study.
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Maria L Alcaide, Natasa Strbo, Laura Romero, Deborah L Jones, Violeta J Rodriguez, Kristopher Arheart, Octavio Martinez, Hector Bolivar, Eckhard R Podack, and Margaret A Fischl
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Medicine ,Science - Abstract
Bacterial vaginosis (BV) is the most common female reproductive tract infection and is associated with an increased risk of acquiring and transmitting HIV by a mechanism that is not well understood. Gamma delta (GD) T cells are essential components of the adaptive and innate immune system, are present in the female reproductive tract, and play an important role in epithelial barrier protection. GD1 cells predominate in the mucosal tissue and are important in maintaining mucosal integrity. GD2 cells predominate in peripheral blood and play a role in humoral immunity and in the immune response to pathogens. HIV infection is associated with changes in GD T cells frequencies in the periphery and in the female reproductive tract. The objective of this study is to evaluate if changes in vaginal flora occurring with BV are associated with changes in endocervical GD T cell responses, which could account for increased susceptibility to HIV. Seventeen HIV-infected (HIV+) and 17 HIV-uninfected (HIV-) pre-menopausal women underwent collection of vaginal swabs and endocervical cytobrushes. Vaginal flora was assessed using the Nugent score. GD T cells were assessed in cytobrush samples by flow cytometry. Median Nugent score was 5.0 and 41% of women had abnormal vaginal flora. In HIV uninfected women there was a negative correlation between Nugent score and cervical GD1 T cells (b for interaction = - 0.176, p
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- 2016
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39. DNA Assembly in 3D Printed Fluidics.
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William G Patrick, Alec A K Nielsen, Steven J Keating, Taylor J Levy, Che-Wei Wang, Jaime J Rivera, Octavio Mondragón-Palomino, Peter A Carr, Christopher A Voigt, Neri Oxman, and David S Kong
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Medicine ,Science - Abstract
The process of connecting genetic parts-DNA assembly-is a foundational technology for synthetic biology. Microfluidics present an attractive solution for minimizing use of costly reagents, enabling multiplexed reactions, and automating protocols by integrating multiple protocol steps. However, microfluidics fabrication and operation can be expensive and requires expertise, limiting access to the technology. With advances in commodity digital fabrication tools, it is now possible to directly print fluidic devices and supporting hardware. 3D printed micro- and millifluidic devices are inexpensive, easy to make and quick to produce. We demonstrate Golden Gate DNA assembly in 3D-printed fluidics with reaction volumes as small as 490 nL, channel widths as fine as 220 microns, and per unit part costs ranging from $0.61 to $5.71. A 3D-printed syringe pump with an accompanying programmable software interface was designed and fabricated to operate the devices. Quick turnaround and inexpensive materials allowed for rapid exploration of device parameters, demonstrating a manufacturing paradigm for designing and fabricating hardware for synthetic biology.
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- 2015
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40. How Many Genes Are Expressed in a Transcriptome? Estimation and Results for RNA-Seq.
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Luis Fernando García-Ortega and Octavio Martínez
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Medicine ,Science - Abstract
RNA-seq experiments estimate the number of genes expressed in a transcriptome as well as their relative frequencies. However, an undetermined number of genes can remain undetected due to their low expression relative to the sample size (sequence depth). Estimation of the true number of genes expressed in a transcriptome is essential in order to determine which genes are exclusively expressed in specific tissues or under particular conditions. A reliable estimate of the true number of expressed genes is also required to accurately measure transcriptome changes and to predict the sequencing depth needed to increase the proportion of detected genes. This problem is analogous to ecological sampling problems such as estimating the number of species at a given site. Here we present a non-parametric estimator for the number of undetected genes as well as for the extra sample size needed to detect a given proportion of the undetected genes. Our estimators are superior to ones already published by having smaller standard errors and biases. We applied our method to a set of 32 publicly available RNA-seq experiments, including the evaluation of 311 individually sequenced libraries. We found that in the majority of the cases more than one thousand genes are undetected, and that on average approximately 6% of the expressed genes per accession remain undetected. This figure increases to approximately 10% if individual sequencing libraries are analyzed. Our method is also applicable to metagenomic experiments. Using our method, the number of undetected genes as well as the sample size needed to detect them can be calculated, leading to more accurate and complete gene expression studies.
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- 2015
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41. An Ornithopod-Dominated Tracksite from the Lower Cretaceous Jiaguan Formation (Barremian-Albian) of Qijiang, South-Central China: New Discoveries, Ichnotaxonomy, Preservation and Palaeoecology.
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Lida Xing, Martin G Lockley, Daniel Marty, Jianping Zhang, Yan Wang, Hendrik Klein, Richard T McCrea, Lisa G Buckley, Matteo Belvedere, Octávio Mateus, Gerard D Gierliński, Laura Piñuela, W Scott Persons, Fengping Wang, Hao Ran, Hui Dai, and Xianming Xie
- Subjects
Medicine ,Science - Abstract
The historically-famous Lotus Fortress site, a deep 1.5-3.0-meter-high, 200-meter-long horizonal notch high up in near-vertical sandstone cliffs comprising the Cretaceous Jiaguan Formation, has been known since the 13th Century as an impregnable defensive position. The site is also extraordinary for having multiple tetrapod track-bearing levels, of which the lower two form the floor of part of the notch, and yield very well preserved asseamblages of ornithopod, bird (avian theropod) and pterosaur tracks. Trackway counts indicate that ornithopods dominate (69%) accounting for at least 165 trackmakers, followed by bird (18%), sauropod (10%), and pterosaur (3%). Previous studies designated Lotus Fortress as the type locality of Caririchnium lotus and Wupus agilis both of which are recognized here as valid ichnotaxa. On the basis of multiple parallel trackways both are interpreted as representing the trackways of gregarious species. C. lotus is redescribed here in detail and interpreted to indicate two age cohorts representing subadults that were sometimes bipedal and larger quadrupedal adults. Two other previously described dinosaurian ichnospecies, are here reinterpreted as underprints and considered nomina dubia. Like a growing number of significant tetrapod tracksites in China the Lotus Fortress site reveals new information about the composition of tetrapod faunas from formations in which the skeletal record is sparse. In particular, the site shows the relatively high abundance of Caririchium in a region where saurischian ichnofaunas are often dominant. It is also the only site known to have yielded Wupus agilis. In combination with information from other tracksites from the Jiaguan formation and other Cretaceous formations in the region, the track record is proving increasingly impotant as a major source of information on the vertebrate faunas of the region. The Lotus Fortress site has been developed as a spectacular, geologically-, paleontologically- and a culturally-significant destination within Qijiang National Geological Park.
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- 2015
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42. Hepatitis B vaccine responsiveness and clinical outcomes in HIV controllers.
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Jason F Okulicz, Octavio Mesner, Anuradha Ganesan, Thomas A O'Bryan, Robert G Deiss, and Brian K Agan
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Medicine ,Science - Abstract
BackgroundHepatitis B virus (HBV) vaccine responsiveness is associated with reduced risk of AIDS or death in HIV-infected individuals. Although HIV controllers (HIC) typically have favorable immunologic and clinical characteristics compared to non-controllers, vaccine responsiveness has not been studied.Methods and findingsIn the U.S. Military HIV Natural History Study, HBV vaccine response was defined as antibody to hepatitis B surface antigen (anti-HBs) ≥ 10 IU/L after last vaccination. For determination of vaccine responsiveness, HIC (n = 44) and treatment-naïve non-controllers (n = 476) were not on highly active antiretroviral therapy (HAART) when vaccinated while treated non-controllers (n = 284) received all HBV vaccine doses during viral load (VL)-suppressive HAART. Progression to AIDS or death was also compared for all HIC (n = 143) and non-controllers (n = 1566) with documented anti-HBs regardless of the timing of HBV vaccination. Positive vaccine responses were more common in HIC (65.9%) compared to HAART-naïve non-controllers (36.6%; PConclusionsHIC have improved HBV vaccine responsiveness compared to treatment-naïve non-controllers, but similar to those on VL-suppressive HAART. Progression to AIDS or death can be predicted by HBV vaccine responder status for non-controllers, however these events are rarely observed in HIC.
- Published
- 2014
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43. Microhabitat types promote the genetic structure of a micro-endemic and critically endangered mole salamander (Ambystoma leorae) of Central Mexico.
- Author
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Armando Sunny, Octavio Monroy-Vilchis, Carlos Reyna-Valencia, and Martha M Zarco-González
- Subjects
Medicine ,Science - Abstract
The reduced immigration and emigration rates resulting from the lack of landscape connectivity of patches and the hospitality of the intervening matrix could favor the loss of alleles through genetic drift and an increased chance of inbreeding. In order for isolated populations to maintain sufficient levels of genetic diversity and adapt to environmental changes, one important conservation goal must be to preserve or reestablish connectivity among patches in a fragmented landscape. We studied the last known population of Ambystoma leorae, an endemic and critically threatened species. The aims of this study were: (1) to assess the demographic parameters of A. leorae and to distinguish and characterize the microhabitats in the river, (2) to determine the number of existing genetic groups or demes of A. leorae and to describe possible relationships between microhabitats types and demes, (3) to determine gene flow between demes, and (4) to search for geographic locations of genetic discontinuities that limit gene flow between demes. We found three types of microhabitats and three genetically differentiated subpopulations with a significant level of genetic structure. In addition, we found slight genetic barriers. Our results suggest that mole salamander's species are very sensitive to microhabitat features and relatively narrow obstacles in their path. The estimates of bidirectional gene flow are consistent with the pattern of a stepping stone model between demes, where migration occurs between adjacent demes, but there is low gene flow between distant demes. We can also conclude that there is a positive correlation between microhabitats and genetic structure in this population.
- Published
- 2014
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44. Lévy flights and self-similar exploratory behaviour of termite workers: beyond model fitting.
- Author
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Octavio Miramontes, Og DeSouza, Leticia Ribeiro Paiva, Alessandra Marins, and Sirio Orozco
- Subjects
Medicine ,Science - Abstract
Animal movements have been related to optimal foraging strategies where self-similar trajectories are central. Most of the experimental studies done so far have focused mainly on fitting statistical models to data in order to test for movement patterns described by power-laws. Here we show by analyzing over half a million movement displacements that isolated termite workers actually exhibit a range of very interesting dynamical properties--including Lévy flights--in their exploratory behaviour. Going beyond the current trend of statistical model fitting alone, our study analyses anomalous diffusion and structure functions to estimate values of the scaling exponents describing displacement statistics. We evince the fractal nature of the movement patterns and show how the scaling exponents describing termite space exploration intriguingly comply with mathematical relations found in the physics of transport phenomena. By doing this, we rescue a rich variety of physical and biological phenomenology that can be potentially important and meaningful for the study of complex animal behavior and, in particular, for the study of how patterns of exploratory behaviour of individual social insects may impact not only their feeding demands but also nestmate encounter patterns and, hence, their dynamics at the social scale.
- Published
- 2014
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45. Torvosaurus gurneyi n. sp., the largest terrestrial predator from Europe, and a proposed terminology of the maxilla anatomy in nonavian theropods.
- Author
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Christophe Hendrickx and Octávio Mateus
- Subjects
Medicine ,Science - Abstract
The Lourinhã Formation (Kimmeridgian-Tithonian) of Central West Portugal is well known for its diversified dinosaur fauna similar to that of the Morrison Formation of North America; both areas share dinosaur taxa including the top predator Torvosaurus, reported in Portugal. The material assigned to the Portuguese T. tanneri, consisting of a right maxilla and an incomplete caudal centrum, was briefly described in the literature and a thorough description of these bones is here given for the first time. A comparison with material referred to Torvosaurus tanneri allows us to highlight some important differences justifying the creation of a distinct Eastern species. Torvosaurus gurneyi n. sp. displays two autapomorphies among Megalosauroidea, a maxilla possessing fewer than eleven teeth and an interdental wall nearly coincidental with the lateral wall of the maxillary body. In addition, it differs from T. tanneri by a reduced number of maxillary teeth, the absence of interdental plates terminating ventrally by broad V-shaped points and falling short relative to the lateral maxillary wall, and the absence of a protuberant ridge on the anterior part of the medial shelf, posterior to the anteromedial process. T. gurneyi is the largest theropod from the Lourinhã Formation of Portugal and the largest land predator discovered in Europe hitherto. This taxon supports the mechanism of vicariance that occurred in the Iberian Meseta during the Late Jurassic when the proto-Atlantic was already well formed. A fragment of maxilla from the Lourinhã Formation referred to Torvosaurus sp. is ascribed to this new species, and several other bones, including a femur, a tibia and embryonic material all from the Kimmeridgian-Tithonian of Portugal, are tentatively assigned to T. gurneyi. A standard terminology and notation of the theropod maxilla is also proposed and a record of the Torvosaurus material from Portugal is given.
- Published
- 2014
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46. Analysis and optimization of bulk DNA sampling with binary scoring for germplasm characterization.
- Author
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M Humberto Reyes-Valdés, Amalio Santacruz-Varela, Octavio Martínez, June Simpson, Corina Hayano-Kanashiro, and Celso Cortés-Romero
- Subjects
Medicine ,Science - Abstract
The strategy of bulk DNA sampling has been a valuable method for studying large numbers of individuals through genetic markers. The application of this strategy for discrimination among germplasm sources was analyzed through information theory, considering the case of polymorphic alleles scored binarily for their presence or absence in DNA pools. We defined the informativeness of a set of marker loci in bulks as the mutual information between genotype and population identity, composed by two terms: diversity and noise. The first term is the entropy of bulk genotypes, whereas the noise term is measured through the conditional entropy of bulk genotypes given germplasm sources. Thus, optimizing marker information implies increasing diversity and reducing noise. Simple formulas were devised to estimate marker information per allele from a set of estimated allele frequencies across populations. As an example, they allowed optimization of bulk size for SSR genotyping in maize, from allele frequencies estimated in a sample of 56 maize populations. It was found that a sample of 30 plants from a random mating population is adequate for maize germplasm SSR characterization. We analyzed the use of divided bulks to overcome the allele dilution problem in DNA pools, and concluded that samples of 30 plants divided into three bulks of 10 plants are efficient to characterize maize germplasm sources through SSR with a good control of the dilution problem. We estimated the informativeness of 30 SSR loci from the estimated allele frequencies in maize populations, and found a wide variation of marker informativeness, which positively correlated with the number of alleles per locus.
- Published
- 2013
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47. How plants sense wounds: damaged-self recognition is based on plant-derived elicitors and induces octadecanoid signaling.
- Author
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Martin Heil, Enrique Ibarra-Laclette, Rosa M Adame-Álvarez, Octavio Martínez, Enrique Ramirez-Chávez, Jorge Molina-Torres, and Luis Herrera-Estrella
- Subjects
Medicine ,Science - Abstract
BackgroundAnimal-derived elicitors can be used by plants to detect herbivory but they function only in specific insect-plant interactions. How can plants generally perceive damage caused by herbivores? Damaged-self recognition occurs when plants perceive molecular signals of damage: degraded plant molecules or molecules localized outside their original compartment.Methodology/principal findingsFlame wounding or applying leaf extract or solutions of sucrose or ATP to slightly wounded lima bean (Phaseolus lunatus) leaves induced the secretion of extrafloral nectar, an indirect defense mechanism. Chemically related molecules that would not be released in high concentrations from damaged plant cells (glucose, fructose, salt, and sorbitol) did not elicit a detectable response, excluding osmotic shock as an alternative explanation. Treatments inducing extrafloral nectar secretion also enhanced endogenous concentrations of the defense hormone jasmonic acid (JA). Endogenous JA was also induced by mechanically damaging leaves of lima bean, Arabidopsis, maize, strawberry, sesame and tomato. In lima bean, tomato and sesame, the application of leaf extract further increased endogenous JA content, indicating that damaged-self recognition is taxonomically widely distributed. Transcriptomic patterns obtained with untargeted 454 pyrosequencing of lima bean in response to flame wounding or the application of leaf extract or JA were highly similar to each other, but differed from the response to mere mechanical damage. We conclude that the amount or concentration of damaged-self signals can quantitatively determine the intensity of the wound response and that the full damaged-self response requires the disruption of many cells.Conclusions/significanceNumerous compounds function as JA-inducing elicitors in different plant species. Most of them are, contain, or release, plant-derived molecular motifs. Damaged-self recognition represents a taxonomically widespread mechanism that contributes to the perception of herbivore feeding by plants. This strategy is independent of insect-derived elicitors and, therefore, allows plants to maintain evolutionary control over their interaction with herbivores.
- Published
- 2012
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48. The effects of spatially heterogeneous prey distributions on detection patterns in foraging seabirds.
- Author
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Octavio Miramontes, Denis Boyer, and Frederic Bartumeus
- Subjects
Medicine ,Science - Abstract
Many attempts to relate animal foraging patterns to landscape heterogeneity are focused on the analysis of foragers movements. Resource detection patterns in space and time are not commonly studied, yet they are tightly coupled to landscape properties and add relevant information on foraging behavior. By exploring simple foraging models in unpredictable environments we show that the distribution of intervals between detected prey (detection statistics) is mostly determined by the spatial structure of the prey field and essentially distinct from predator displacement statistics. Detections are expected to be Poissonian in uniform random environments for markedly different foraging movements (e.g. Lévy and ballistic). This prediction is supported by data on the time intervals between diving events on short-range foraging seabirds such as the thick-billed murre (Uria lomvia). However, Poissonian detection statistics is not observed in long-range seabirds such as the wandering albatross (Diomedea exulans) due to the fractal nature of the prey field, covering a wide range of spatial scales. For this scenario, models of fractal prey fields induce non-Poissonian patterns of detection in good agreement with two albatross data sets. We find that the specific shape of the distribution of time intervals between prey detection is mainly driven by meso and submeso-scale landscape structures and depends little on the forager strategy or behavioral responses.
- Published
- 2012
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49. Cancer reduces transcriptome specialization.
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Octavio Martínez, M Humberto Reyes-Valdés, and Luis Herrera-Estrella
- Subjects
Medicine ,Science - Abstract
A central goal of cancer biology is to understand how cells from this family of genetic diseases undergo specific morphological and physiological changes and regress to a de-regulated state of the cell cycle. The fact that tumors are unable to perform most of the specific functions of the original tissue led us to hypothesize that the degree of specialization of the transcriptome of cancerous tissues must be less than their normal counterparts. With the aid of information theory tools, we analyzed four datasets derived from transcriptomes of normal and tumor tissues to quantitatively test the hypothesis that cancer reduces transcriptome specialization. Here, we show that the transcriptional specialization of a tumor is significantly less than the corresponding normal tissue and comparable with the specialization of dedifferentiated embryonic stem cells. Furthermore, we demonstrate that the drop in specialization in cancerous tissues is largely due to a decrease in expression of genes that are highly specific to the normal organ. This approach gives us a better understanding of carcinogenesis and offers new tools for the identification of genes that are highly influential in cancer progression.
- Published
- 2010
- Full Text
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