154 results on '"Madrigal A"'
Search Results
2. Elevational and seasonal patterns of plant pollinator networks in two highland tropical ecosystems in Costa Rica
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E. Jacob Cristóbal-Perez, Gilbert Barrantes, Alfredo Cascante-Marín, Paul Hanson, Beatriz Picado, Nicole Gamboa-Barrantes, Geovanna Rojas-Malavasi, Manuel A. Zumbado, Ruth Madrigal-Brenes, Silvana Martén-Rodríguez, Mauricio Quesada, and Eric J. Fuchs
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Medicine ,Science - Published
- 2024
3. Assessing the predictive value of morphological traits on primary lifestyle of birds through the extreme gradient boosting algorithm.
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Luis Javier Madrigal-Roca
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Medicine ,Science - Abstract
The relationship between morphological traits and ecological performance in birds is an important area of research, as it can help us to understand how birds are able to adapt and how they are affected by changes in their environment. Many studies have investigated the relationship between morphological traits and certain aspects of the performance and ecological niche of these animals. However, the relationship between morphological traits and the primary lifestyle of birds has not previously been explored. This paper aims to evaluate the predictive potential of morphological data to determine the primary lifestyle of birds through a tree-based machine learning algorithm. By doing this, it is also possible to evaluate these artificial categories that we used to split up birds and know whether they are suitable for dividing them in function of shared morphological characteristics or need a redefinition under more discriminant criteria. Supplementary dataset 1 of the AVONET project was used, which comprises the 11 morphological predictors used in this work and the classification according to the primary lifestyle for more than 95% of the existing bird species. For all morphological traits used, statistically significant univariate differences were found between primary lifestyles. The three fitted machine learning models showed high accuracy, in all cases above 78% and superior to the ones achieved through traditional approaches used as contrasts. The results obtained provide evidence that primary lifestyle can be predicted in birds based on morphological traits, as well as more insights about the relevance of functional traits for ecological modeling. This is another step forward in our mechanistic understanding of bird ecology, while exploring how birds have adapted to their environments and how they interact with their surroundings.
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- 2024
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4. A fast, easy, cost-free method to remove excess dye or drug from small extracellular vesicle solution
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Isaioglou, Ioannis, primary, Lopez-Madrigal, Gloria, additional, and Merzaban, Jasmeen S., additional
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- 2024
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5. Proximal determinants of suboptimal early child development during the first three years of life in socially deprived Mexican contexts
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Edson Serván-Mori, Amado D. Quezada-Sánchez, Evelyn Fuentes-Rivera, Carlos Pineda-Antunez, María del Carmen Hernández-Chávez, Angélica García-Martínez, Raquel García-Feregrino, Abby Madrigal, Bárbara Guerrero, Gerónimo Medrano, and Lourdes Schnaas
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Medicine ,Science - Published
- 2023
6. First identification and characterization of ovine gammaherpesvirus type 2 in horses and artiodactyla from an outbreak of malignant catarrhal fever in Mexico.
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Tania Lucia Madrigal-Valencia, Manuel Saavedra-Montañez, Armando Pérez-Torres, Jesús Hernández, Joaquim Segalés, Yesmín Domínguez Hernández, Irma Eugenia Candanosa-Aranda, Alfredo Pérez-Guiot, and Humberto Ramírez-Mendoza
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Medicine ,Science - Abstract
Ovine gammaherpesvirus 2 (OvHV-2), a member of the genus Macavirus, causes sheep-associated malignant catarrhal fever (SA-MCF), a fatal lymphoproliferative disease affecting a wide variety of ungulates in addition to horses. This study described an outbreak of SA-MCF in Mexico and the identification of the OvHV-2 virus in primary rabbit testis cultures through the generation of intranuclear inclusion bodies, syncytia, immunofluorescence (IF), immunocytochemistry (ICC), immunohistochemistry (IHC), endpoint polymerase chain reaction (PCR), and partial sequencing of the ORF75 gene. The animals involved in this outbreak showed mucogingival ulcers in the vestibule of the mouth and tongue, hypersalivation, corneal opacity, reduced food consumption, and weight loss of variable severity. These clinical signs and the histopathological findings suggested the diagnosis of SA-MCF. Buffy coat fractions from the anticoagulated blood samples of ill animals were collected and analyzed by PCR. Positive buffy coats were used to inoculate the primary cell cultures of rabbit testis to identify the virus. Small clusters of refractile cytomegalic cells, characteristic of viral cytopathic effects, were observed between 48 and 72 h post-infection. Furthermore, intranuclear acidophilic inclusion bodies (IBs) were identified in the inoculated primary culture cells, and the cytoplasm showed immunoreactivity with hyperimmune rabbit serum against OvHV-2. Moreover, in the liver histological sections from sick deer, immunoreactive juxtanuclear IBs were identified with the same rabbit hyperimmune serum. The obtained sequences were aligned with the OvHV-2 sequences reported in GenBank and revealed a nucleotide identity higher than 98%. Based on the evidence provided in this study, we conclude that the outbreak of SA-MCF in the municipality of Tequisquiapan in the state of Queretaro, Mexico, was caused by OvHV-2. This is the second study reporting that horses are susceptible to OvHV-2 infection and can develop SA-MCF. We identified for the first time in Mexico, the presence of OvHV-2 in buffy coats from horses and Artiodactyla.
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- 2023
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7. Community recommendations on biobank governance: Results from a deliberative community engagement in California
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Dry, Sarah M, Garrett, Sarah B, Koenig, Barbara A, Brown, Arleen F, Burgess, Michael M, Hult, Jen R, Longstaff, Holly, Wilcox, Elizabeth S, Contreras, Sigrid Karina Madrigal, Martinez, Arturo, Boyd, Elizabeth A, and Dohan, Daniel
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Health Services and Systems ,Health Sciences ,Human Society ,Clinical Research ,Generic health relevance ,Adult ,Aged ,Biological Specimen Banks ,Biomedical Research ,Community Participation ,Female ,Health Knowledge ,Attitudes ,Practice ,Health Surveys ,Humans ,Informed Consent ,Los Angeles ,Male ,Middle Aged ,Qualitative Research ,San Francisco ,Universities ,General Science & Technology - Abstract
United States-based biorepositories are on the cusp of substantial change in regulatory oversight at the same time that they are increasingly including samples and data from large populations, e.g. all patients in healthcare system. It is appropriate to engage stakeholders from these populations in new governance arrangements. We sought to describe community recommendations for biorepository governance and oversight using deliberative community engagement (DCE), a qualitative research method designed to elicit lay perspectives on complex technical issues. We asked for stakeholders to provide input on governance of large biorepositories at the University of California (UC), a public university. We defined state residents as stakeholders and recruited residents from two large metropolitan areas, Los Angeles (LA) and San Francisco (SF). In LA, we recruited English and Spanish speakers; in SF the DCE was conducted in English only. We recruited individuals who had completed the 2009 California Health Interview Survey and were willing to be re-contacted for future studies. Using stratified random sampling (by age, education, race/ethnicity), we contacted 162 potential deliberants of whom 53 agreed to participate and 51 completed the 4-day DCE in June (LA) and September-October (SF), 2013. Each DCE included discussion among deliberants facilitated by a trained staff and simultaneously-translated in LA. Deliberants also received a briefing book describing biorepository operations and regulation. During the final day of the DCE, deliberants voted on governance and oversight recommendations using an audience response system. This paper describes 23 recommendations (of 57 total) that address issues including: educating the public, sharing samples broadly, monitoring researcher behavior, using informative consent procedures, and involving community members in a transparent process of biobank governance. This project demonstrates the feasibility of obtaining meaningful input on biorepository governance from diverse lay stakeholders. Such input should be considered as research institutions respond to changes in biorepository regulation.
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- 2017
8. Assessing the predictive value of morphological traits on primary lifestyle of birds through the extreme gradient boosting algorithm
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Madrigal-Roca, Luis Javier, primary
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- 2024
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9. Proximal determinants of suboptimal early child development during the first three years of life in socially deprived Mexican contexts
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Serván-Mori, Edson, primary, Quezada-Sánchez, Amado D., additional, Fuentes-Rivera, Evelyn, additional, Pineda-Antunez, Carlos, additional, Hernández-Chávez, María del Carmen, additional, García-Martínez, Angélica, additional, García-Feregrino, Raquel, additional, Madrigal, Abby, additional, Guerrero, Bárbara, additional, Medrano, Gerónimo, additional, and Schnaas, Lourdes, additional
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- 2023
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10. Early neurological development and nutritional status in Mexican socially deprived contexts
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Edson Serván-Mori, Evelyn Fuentes-Rivera, Amado D. Quezada, Carlos Pineda-Antunez, María del Carmen Hernández-Chávez, Angélica García-Martínez, Abby Madrigal, Raquel García-Feregrino, Tania Santiago-Angelino, María Hernández-Serrato, and Lourdes Schnaas
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Medicine ,Science - Abstract
Early childhood development (ECD) is a critical stage in the intergenerational process of human development. Targeted interventions depend on accurate and up-to-date ECD measurements. This paper presents estimates for the nutritional and neurodevelopmental status of socially marginalized children in Mexico. We performed a cross-sectional study based on data collected in 2019–2020 during home visits to 1,176 children aged 0–38 months across 24 highly marginalized locations in Oaxaca. We assessed nutritional status according to the World Health Organization 2006 child-growth standards and ECD status using the Child Development Evaluation Test, 2nd Edition. We stratified results by sex. Prevalence of stunting was 5.3 percentage points (p.p.) higher (p = 0.023) in males (25.3%; 95% CI: 20.2%, 31.1%) compared to females (20.0%; 95% CI: 15.0%, 26.1%). Overall prevalence rates stood at 5.7% (95% CI: 4.0%, 8.1%) for underweight, 1.5% (95% CI: 0.9%, 2.7%) for wasting and 3.6% (95% CI: 2.3%, 5.7%) for overweight/obesity, with no significant differences by sex. Prevalence of normal development was 8.3 p.p. lower (p = 0.001) in males (39.3%; 95% CI: 34.5%, 44.4%) compared to females (47.6%; 95% CI: 41.6%, 53.6%). By development area, the highest prevalence of suboptimal outcomes among children with developmental lag or at risk of delay was observed in their gross motor and language skills: 24.1% (95% CI: 20.0%, 28.8%) and 38.6% (95% CI: 34.0%, 43.3%), respectively. The largest difference between the sexes was found in the language area. Our results show that childhood development strategies have been insufficient thus far in the studied population. Programs specifically designed to prevent ECD lags and bridge inequality gaps are urgently needed. Trial registration: ClinicalTrials.gov ID: NCT04210362.
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- 2022
11. Sickle cell disease among Latinx in California.
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Jhaqueline Valle, Judith R Baker, Daniel Madrigal, Juana Ferrerosa, and Susan Paulukonis
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Medicine ,Science - Abstract
IntroductionAfter African Americans, Latinx are the second largest population affected by Sickle Cell Disease (SCD) in the U.S. However, research has largely ignored how this devastating rare blood disorder specifically affects Latinx nationwide.MethodsThis study compared demographics, genotypes, primary insurance, and health care utilization among Latinx and non-Latinx Californians living with SCD, using data from the California SCD Data Collection Program (2016-2018) and newborn screening cases 2000-2017.ResultsStemming from 6,837 SCD patients, 501(7%) were Latinx. Latinx with SCD (Lx-SCD) were statistically significantly younger than non-Latinx (NLx-SCD) counterparts. Within both groups, females predominated, with 70% being insured by Medicaid. Mean Emergency Department encounters were statistically significantly lower among Lx-SCD adults.DiscussionLx-SCD differ in age, genotype, and Emergency Department utilization, when compared to NLx-SCD counterparts in California. Latinx are now the largest racial and/or ethnic group in the US, and their presence in SCD population is expected to grow. Therefore, their specific demographic, genotypic, and health care utilization characteristics merit attention to inform policies and programs that will improve their health.
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- 2022
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12. Mutations in SORL1 and MTHFDL1 possibly contribute to the development of Alzheimer's disease in a multigenerational Colombian Family.
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Johanna Alexandra Tejada Moreno, Andrés Villegas Lanau, Lucia Madrigal Zapata, Ana Yulied Baena Pineda, Juan Velez Hernandez, Omer Campo Nieto, Alejandro Soto Ospina, Pedronel Araque Marín, Lavanya Rishishwar, Emily T Norris, Aroon T Chande, I King Jordan, and Gabriel Bedoya Berrio
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Medicine ,Science - Abstract
Alzheimer's disease (AD) is the most common cause of dementia in the elderly, affecting over 50 million people worldwide in 2020 and this number will triple to 152 million by 2050. Much of the increase will be in developing countries like Colombia. In familial forms, highly penetrant mutations have been identified in three genes, APP, PSEN1, and PSEN2, supporting a role for amyloid-β peptide. In sporadic forms, more than 30 risk genes involved in the lipid metabolism, the immune system, and synaptic functioning mechanisms. We used whole-exome sequencing (WES) to evaluate a family of 97 members, spanning three generations, with a familiar AD, and without mutations in APP, PSEN1, or PSEN2. We sequenced two affected and one unaffected member with the aim of identifying genetic variants that could explain the presence of the disease in the family and the candidate variants were validated in eleven members. We also built a structural model to try to determine the effect on protein function. WES analysis identified two rare variants in SORL1 and MTHFD1L genes segregating in the family with other potential risk variants in APOE, ABCA7, and CHAT, suggesting an oligogenic inheritance. Additionally, the structural 3D models of SORL1 and MTHFD1L variants shows that these variants produce polarity changes that favor hydrophobic interactions, resulting in local structural changes that could affect the protein function and may contribute to the development of the disease in this family.
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- 2022
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13. MicNet toolbox: Visualizing and unraveling a microbial network.
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Natalia Favila, David Madrigal-Trejo, Daniel Legorreta, Jazmín Sánchez-Pérez, Laura Espinosa-Asuar, Luis E Eguiarte, and Valeria Souza
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Medicine ,Science - Abstract
Applications of network theory to microbial ecology are an emerging and promising approach to understanding both global and local patterns in the structure and interplay of these microbial communities. In this paper, we present an open-source python toolbox which consists of two modules: on one hand, we introduce a visualization module that incorporates the use of UMAP, a dimensionality reduction technique that focuses on local patterns, and HDBSCAN, a clustering technique based on density; on the other hand, we have included a module that runs an enhanced version of the SparCC code, sustaining larger datasets than before, and we couple the resulting networks with network theory analyses to describe the resulting co-occurrence networks, including several novel analyses, such as structural balance metrics and a proposal to discover the underlying topology of a co-occurrence network. We validated the proposed toolbox on 1) a simple and well described biological network of kombucha, consisting of 48 ASVs, and 2) we validate the improvements of our new version of SparCC. Finally, we showcase the use of the MicNet toolbox on a large dataset from Archean Domes, consisting of more than 2,000 ASVs. Our toolbox is freely available as a github repository (https://github.com/Labevo/MicNetToolbox), and it is accompanied by a web dashboard (http://micnetapplb-1212130533.us-east-1.elb.amazonaws.com) that can be used in a simple and straightforward manner with relative abundance data. This easy-to-use implementation is aimed to microbial ecologists with little to no experience in programming, while the most experienced bioinformatics will also be able to manipulate the source code's functions with ease.
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- 2022
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14. First identification and characterization of ovine gammaherpesvirus type 2 in horses and artiodactyla from an outbreak of malignant catarrhal fever in Mexico
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Madrigal-Valencia, Tania Lucia, primary, Saavedra-Montañez, Manuel, additional, Pérez-Torres, Armando, additional, Hernández, Jesús, additional, Segalés, Joaquim, additional, Hernández, Yesmín Domínguez, additional, Candanosa-Aranda, Irma Eugenia, additional, Pérez-Guiot, Alfredo, additional, and Ramírez-Mendoza, Humberto, additional
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- 2023
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15. CCR2/CCL2 and CMKLR1/RvE1 chemokines system levels are associated with insulin resistance in rheumatoid arthritis.
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Gustavo Ignacio Diaz-Rubio, Fernanda-Isadora Corona-Meraz, Perla-Monserrat Madrigal-Ruiz, Jesús-Aureliano Robles-De Anda, Eduardo Gómez-Bañuelos, Jorge Castro-Albarran, Luis-Javier Flores-Alvarado, Mónica Vázquez-Del Mercado, Felipe de Jesús Pérez-Vázquez, Oscar-Enrique Pizano-Martínez, and Rosa-Elena Navarro-Hernández
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Medicine ,Science - Abstract
Rheumatoid arthritis (RA) has been associated with insulin resistance (IR). Due to an excess in storage of white adipose tissue, IR has an inflammatory process that overlaps with RA. This is performed by the activation/migration of monocytes carried out by the CCR2/CCL2 and CMKLR1/RvE1 chemokines systems. Furthermore, these can potentiate chronic inflammation which is the central axis in the immunopathogenesis of RA. We evaluated the association between the relative expression of CCR2 and CMKLR1 and the serum levels of their ligands CCL2 and RvE1, in the context of adiposity status with IR as a comorbidity in RA. We studied 138 controls and 138 RA-patients classified with and without IR. We evaluated adiposity, RA activity, IR status and immunometabolic profiles by routine methods. Insulin, CCL2 and RvE1 serum levels were determined by ELISA. Relative expression of CCR2, CMKLR1 and RPS28 as constitutive gene by SYBR green RT-qPCR and 2-ΔΔCT method. Increased measurements were observed of body adiposity and metabolic status as follows: RA with IR>control group with IR>RA without IR> control group without IR. CCR2 and CMKLR1 relative expression was increased in RA without IR versus control without IR. CCR2: 2.3- and 1.3-fold increase and CMKLR1: 3.5- and 2.7-fold increase, respectively. Whereas, CCR2 expression correlates with CMKLR1 expression (rho = 0.331) and IR status (rho = 0.497 to 0.548). CMKLR1 expression correlates with inflammation markers (rho = 0.224 to 0.418). CCL2 levels were increased in the RA groups but levels of RvE1 were increased in RA without IR. We conclude that in RA with IR, the chemokine receptors expression pattern showed a parallel increase with their respective ligands. RA and IR in conjunction with the pathological distribution of body fat mass might exacerbate chronic inflammation. These results suggest that high CCL2 levels and compensatory RvE1 levels might not be enough to resolve the inflammation by themselves.
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- 2021
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16. Sperm kinematic subpopulations of the American crocodile (Crocodylus acutus).
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Anthony Valverde, Olivier Castro-Morales, Mónica Madrigal-Valverde, Marlen Camacho, Vinicio Barquero, Carles Soler, and Eduardo R S Roldan
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Medicine ,Science - Abstract
There has been very limited use of computer assisted semen analysis (CASA) to evaluate reptile sperm. The aim of this study was to examine sperm kinematic variables in American crocodile (Crocodylus acutus) semen samples and to assess whether sperm subpopulations could be characterized. Eight ejaculates (two ejaculates/male) from four sexually mature captive crocodiles were obtained. An ISAS®v1 CASA-Mot system, with an image acquisition rate of 50 Hz, and ISAS®D4C20 counting chambers were used for sperm analyses. The percentages of motile and progressively motile spermatozoa did not differ among animals (P > 0.05) but there was a significant animal effect with regards to kinematic variables (P < 0.05). Principal component (PC) analysis revealed that kinematic variables grouped into three components: PC1, related to velocity; PC2 to progressiveness and PC3 to oscillation. Subpopulation structure analysis identified four groups (P < 0.05), which represented, on average, 9.8%, 32.1%, 26.8%, and 31.3% of the total sperm population. Males differed in the proportion of sperm in each of the kinematic subpopulations. This new approach for the analysis of reptile sperm kinematic subpopulations, reflecting quantifiable parameters generated by CASA system technology, opens up possibilities for future assessments of crocodile sperm and will be useful in the future development of assisted reproduction for these species.
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- 2021
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17. Sexual and gender minority identity in undergraduate medical education: Impact on experience and career trajectory
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Josef Madrigal, Sarah Rudasill, Zachary Tran, Jonathan Bergman, and Peyman Benharash
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Medicine ,Science - Abstract
Introduction The wellbeing of sexual and gender minority (SGM) medical students and the impact of their experiences on career trajectory remain poorly understood. The present study aimed to characterize the incidence of mistreatment in SGM trainees as well as general perspectives on the acceptance of SGM individuals across medical and surgical specialties. Methods This was a cross sectional survey study of all actively enrolled medical students within the six University of California campuses conducted in March 2021. An online, survey tool captured incidence of bullying, discrimination, and suicidal ideation as well as perceived acceptance of SGM identities across specialties measured by slider scale. Differences between SGM and non-SGM respondents were assessed with two-tailed and chi-square tests. Qualitative responses were evaluated utilizing a multi-stage, cutting-and-sorting technique. Results Of approximately 3,205 students eligible for participation, 383 submitted completed surveys, representing a response rate of 12.0%. Of these respondents, 26.9% (n = 103) identified as a sexual or gender minority. Overall, SGM trainees reported higher slider scale scores when asked about being bullied by other students (20.0 vs. 13.9, P = 0.012) and contemplating suicide (14.8 vs. 8.8, P = 0.005). Compared to all other specialties, general surgery and surgical subspecialties had the lowest mean slider scale score (52.8) in perceived acceptance of SGM identities (All P < 0.001). In qualitative responses, students frequently cited lack of diversity as contributing to this perception. Additionally, 67.0% of SGM students had concerns that disclosure of identity would affect their future career with 18.5% planning to not disclose during the residency application process. Conclusions Overall, SGM respondents reported higher incidences of bullying and suicidal ideation as well as increased self-censorship stemming from concerns regarding career advancement, most prominently in surgery. To address such barriers, institutions must actively promote diversity in sexual preference and gender identity regardless of specialty.
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- 2021
18. Enumerating regulatory T cells in cryopreserved umbilical cord blood samples using FOXP3 methylation specific quantitative PCR.
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Richard C Duggleby, Hoi Pat Tsang, Kathryn Strange, Alasdair McWhinnie, Abigail A Lamikanra, David J Roberts, Diana Hernandez, J Alejandro Madrigal, and Robert D Danby
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Medicine ,Science - Abstract
BackgroundAllogeneic haematopoietic cell transplantation (HCT) is a curative therapy for severe haematological disorders. However, it carries significant risk of morbidity and mortality. To improve patient outcomes, better graft selection strategies are needed, incorporating HLA matching with clinically important graft characteristics. Studies have shown that the cellular content of HCT grafts, specifically higher ratios of T regulatory (Tregs)/T cells, are important factors influencing outcomes when using adult peripheral blood mobilised grafts. So far, no equivalent study exists in umbilical cord blood (CB) transplantation due to the limitations of cryopreserved CB samples.Study design and methodsTo establish the most robust and efficient way to measure the Treg content of previously cryopreserved CB units, we compared the enumeration of Treg and CD3+ cells using flow cytometry and an epigenetic, DNA-based methodology. The two methods were assessed for their agreement, consistency and susceptibility to error when enumerating Treg and CD3+ cell numbers in both fresh and cryopreserved CB samples.ResultsEpigenetic enumeration gave consistent and comparable results in both fresh and frozen CB samples. By contrast, assessment of Tregs and CD3+ cells by flow cytometry was only possible in fresh samples due to significant cell death following cryopreservation and thawing.ConclusionEpigenetic assessment offers significant advantages over flow cytometry for analysing cryopreserved CB; similar cell numbers were observed both in fresh and frozen samples. Furthermore, multiple epigenetic assessments can be performed from DNA extracted from small cryopreserved CB segments; often the only CB sample available for clinical studies.
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- 2020
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19. The masked seducers: Lek courtship behavior in the wrinkle-faced bat Centurio senex (Phyllostomidae).
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Bernal Rodríguez-Herrera, Ricardo Sánchez-Calderón, Victor Madrigal-Elizondo, Paulina Rodríguez, Jairo Villalobos, Esteban Hernández, Daniel Zamora-Mejías, Gloria Gessinger, and Marco Tschapka
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Medicine ,Science - Abstract
Centurio senex is an iconic bat characterized by a facial morphology deviating far from all other New World Leaf Nosed Bats (Phyllostomidae). The species has a bizarrely wrinkled face and lacks the characteristic nose leaf. Throughout its distribution from Mexico to Northern South America the species is most of the time rarely captured and only scarce information on its behavior and natural history is available. Centurio senex is frugivorous and one of the few bats documented to consume also hard seeds. Interestingly, the species shows a distinct sexual dimorphism: Adult males have more pronounced facial wrinkles than females and a fold of skin under the chin that can be raised in style of a face mask. We report the first observations on echolocation and mating behavior of Centurio senex, including synchronized audio and video recordings from an aggregation of males in Costa Rica. Over a period of 6 weeks we located a total of 53 perches, where during the first half of the night males were hanging with raised facial masks at a mean height of 2.35 m. Most of the time, the males moved just their wing tips, and spontaneously vocalized in the ultrasound range. Approaches of other individuals resulted in the perching male beating its wings and emitting a very loud, low frequency whistling call. Following such an encounter we recorded a copulation event. The observed aggregation of adult C. senex males is consistent with lek courtship, a behavior described from only few other bat species.
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- 2020
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20. Elevational and seasonal patterns of plant pollinator networks in two highland tropical ecosystems in Costa Rica.
- Author
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Cristóbal-Perez, E. Jacob, Barrantes, Gilbert, Cascante-Marín, Alfredo, Hanson, Paul, Picado, Beatriz, Gamboa-Barrantes, Nicole, Rojas-Malavasi, Geovanna, Zumbado, Manuel A., Madrigal-Brenes, Ruth, Martén-Rodríguez, Silvana, Quesada, Mauricio, and Fuchs, Eric J.
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TROPICAL ecosystems ,MOUNTAIN forests ,POLLINATORS ,UPLANDS ,INSECT-plant relationships - Abstract
Many plant species in high montane ecosystems rely on animal pollination for sexual reproduction, however, our understanding of plant-pollinator interactions in tropical montane habitats is still limited. We compared species diversity and composition of blooming plants and floral visitors, and the structure of plant-floral visitor networks between the Montane Forest and Paramo ecosystems in Costa Rica. We also studied the influence of seasonality on species composition and interaction structure. Given the severe climatic conditions experienced by organisms in habitats above treeline, we expected lower plant and insect richness, as well as less specialized and smaller pollination networks in the Paramo than in Montane Forest where climatic conditions are milder and understory plants are better protected. Accordingly, we found that blooming plants and floral visitor species richness was higher in the Montane Forest than in the Paramo, and in both ecosystems species richness of blooming plants and floral visitors was higher in the rainy season than in the dry season. Interaction networks in the Paramo were smaller and more nested, with lower levels of specialization and modularity than those in the Montane Forest, but there were no seasonal differences within either ecosystem. Beta diversity analyses indicate that differences between ecosystems are likely explained by species turnover, whereas within the Montane Forest differences between seasons are more likely explained by the rewiring of interactions. Results indicate that the decrease in species diversity with elevation affects network structure, increasing nestedness and reducing specialization and modularity. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Comparison of the microbiome, metabolome, and lipidome of obese and non-obese horses.
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Michelle C Coleman, Canaan M Whitfield-Cargile, Rodolfo G Madrigal, and Noah D Cohen
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Medicine ,Science - Abstract
Metabolic diseases such as obesity and type 2 diabetes in humans have been linked to alterations in the gastrointestinal microbiota and metabolome. Knowledge of these associations has improved our understanding of the pathophysiology of these diseases and guided development of diagnostic biomarkers and therapeutic interventions. The cellular and molecular pathophysiology of equine metabolic syndrome (EMS) and obesity in horses, however, remain ill-defined. Thus, the objectives of this study were to characterize the fecal microbiome, fecal metabolome, and circulating lipidome in obese and non-obese horses. The fecal microbiota, fecal metabolome, and serum lipidome were evaluated in obese (case) horses (n = 20) and non-obese (control) horses (n = 20) matched by farm of origin (n = 7). Significant differences in metabolites of the mitochondrial tricarboxylic acid cycle and circulating free fatty acids were identified in the obese horses compared to the non-obese horses. These results indicate that the host and bacterial metabolism should be considered important in obese horses. Further studies to determine whether these associations are causal and the mechanistic basis of the association are warranted because they might reveal diagnostic biomarkers and therapeutic interventions to mitigate obesity, EMS, and sequelae including laminitis.
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- 2019
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22. Comparative transcriptomic analysis and structure prediction of novel Newt proteins.
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Abijeet Singh Mehta, Agustin Luz-Madrigal, Jian-Liang Li, Panagiotis A Tsonis, and Amit Singh
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Medicine ,Science - Abstract
Notophthalmus viridescens (Red-spotted Newt) possess amazing capabilities to regenerate their organs and other tissues. Previously, using a de novo assembly of the newt transcriptome combined with proteomic validation, our group identified a novel family of five protein members expressed in adult tissues during regeneration in Notophthalmus viridescens. The presence of a putative signal peptide suggests that all these proteins are secretory in nature. Here we employed iterative threading assembly refinement (I-TASSER) server to generate three-dimensional structure of these novel Newt proteins and predicted their function. Our data suggests that these proteins could act as ion transporters, and be involved in redox reaction(s). Due to absence of transgenic approaches in N. viridescens, and conservation of genetic machinery across species, we generated transgenic Drosophila melanogaster to misexpress these genes. Expression of 2775 transcripts were compared between these five newly identified Newt genes. We found that genes involved in the developmental process, cell cycle, apoptosis, and immune response are among those that are highly enriched. To validate the RNA Seq. data, expression of six highly regulated genes were verified using real time Quantitative Polymerase Chain Reaction (RT-qPCR). These graded gene expression patterns provide insight into the function of novel protein family identified in Newt, and layout a map for future studies in the field.
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- 2019
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23. Is local trait variation related to total range size of tropical trees?
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Eduardo Chacón-Madrigal, Wolfgang Wanek, Peter Hietz, and Stefan Dullinger
- Subjects
Medicine ,Science - Abstract
The reasons why the range size of closely related species often varies significantly have intrigued scientists for many years. Among other hypotheses, species with high trait variation were suggested to occupy more diverse environments, have more continuity in their distributions, and consequently have larger range sizes. Here, using 34 tree species of lowlands tropical rainforest in southern Costa Rica, we explored whether inherent trait variability expressed at the local scale in functional traits is related to the species' total geographical range size. We formed 17 congeneric pairs of one narrow endemic and one widespread species, sampled 335 individuals and measured eight functional traits: leaf area, leaf thickness, leaf dry matter content, specific leaf area, leaf nitrogen content, leaf phosphorus content, leaf nitrogen to phosphorus ratio, and wood specific gravity. We tested whether there are significant differences in the locally expressed variation of individual traits or in multidimensional trait variance between the species in congeneric pairs and whether species' range size could hence be predicted from local trait variability. However, we could not find such differences between widely distributed and narrow range species. We discuss the possible reasons for these findings including the fact that higher trait variability of widespread species may result from successive local adaptations during range expansion and may hence often be an effect rather than the cause of larger ranges.
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- 2018
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24. Sickle cell disease among Latinx in California
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Valle, Jhaqueline, primary, Baker, Judith R., additional, Madrigal, Daniel, additional, Ferrerosa, Juana, additional, and Paulukonis, Susan, additional
- Published
- 2022
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25. Community recommendations on biobank governance: Results from a deliberative community engagement in California.
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Sarah M Dry, Sarah B Garrett, Barbara A Koenig, Arleen F Brown, Michael M Burgess, Jen R Hult, Holly Longstaff, Elizabeth S Wilcox, Sigrid Karina Madrigal Contreras, Arturo Martinez, Elizabeth A Boyd, and Daniel Dohan
- Subjects
Medicine ,Science - Abstract
United States-based biorepositories are on the cusp of substantial change in regulatory oversight at the same time that they are increasingly including samples and data from large populations, e.g. all patients in healthcare system. It is appropriate to engage stakeholders from these populations in new governance arrangements. We sought to describe community recommendations for biorepository governance and oversight using deliberative community engagement (DCE), a qualitative research method designed to elicit lay perspectives on complex technical issues. We asked for stakeholders to provide input on governance of large biorepositories at the University of California (UC), a public university. We defined state residents as stakeholders and recruited residents from two large metropolitan areas, Los Angeles (LA) and San Francisco (SF). In LA, we recruited English and Spanish speakers; in SF the DCE was conducted in English only. We recruited individuals who had completed the 2009 California Health Interview Survey and were willing to be re-contacted for future studies. Using stratified random sampling (by age, education, race/ethnicity), we contacted 162 potential deliberants of whom 53 agreed to participate and 51 completed the 4-day DCE in June (LA) and September-October (SF), 2013. Each DCE included discussion among deliberants facilitated by a trained staff and simultaneously-translated in LA. Deliberants also received a briefing book describing biorepository operations and regulation. During the final day of the DCE, deliberants voted on governance and oversight recommendations using an audience response system. This paper describes 23 recommendations (of 57 total) that address issues including: educating the public, sharing samples broadly, monitoring researcher behavior, using informative consent procedures, and involving community members in a transparent process of biobank governance. This project demonstrates the feasibility of obtaining meaningful input on biorepository governance from diverse lay stakeholders. Such input should be considered as research institutions respond to changes in biorepository regulation.
- Published
- 2017
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26. Donation of peripheral blood stem cells to unrelated strangers: A thematic analysis.
- Author
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Annelies Billen, J Alejandro Madrigal, Katrina Scior, Bronwen E Shaw, and Andre Strydom
- Subjects
Medicine ,Science - Abstract
Donation of haematopoietic stem cells, either through bone marrow (BM) or peripheral blood stem cell (PBSC) collection, is a generally safe procedure for healthy donors, although side effects are a known risk. Previous research, including our recent quantitative study, has shown that the psychosocial response to donating is usually a positive one and most donors would be willing to donate again in the future. This is often despite experiencing significant side effects during the donation process. Due to the relative recent introduction of PBSC, a comprehensive understanding of the range of physical and emotional issues donors may experience is lacking, as well as an understanding of specific donor characteristics Qualitative research can provide rich narrative data into these areas. This study was set up in order to identify specific donor characteristics and to further explore the relationship between pre-donation physical health and the donation experience, as previously identified in our quantitative study.It involved in-depth telephone interviews with 14 PBSC donors who participated in our original quantitative study. Thematic analysis was used to analyse the findings and the results provide a summary of participants' characteristics using themes and constituent codes.We identified several donor characteristics, including strong intrinsic motivation, altruism, sense of duty, determination, low levels of ambivalence and the ability to develop a strong emotional relationship with an (unknown/anonymous) recipient whilst being able to manage strong feelings and emotions.These personality traits may explain the resilience that has been observed previously in haematopoietic stem cells donors. Significant feelings of grief were reported after a recipient's death. Possibilities to alleviate these symptoms may include raising awareness of potential poor outcomes in the recipient and offering improved counselling services if the recipient dies. We acknowledge several limitations including the sampling frame.
- Published
- 2017
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27. Identification of cis-regulatory sequences reveals potential participation of lola and Deaf1 transcription factors in Anopheles gambiae innate immune response.
- Author
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Bernardo Pérez-Zamorano, Sandra Rosas-Madrigal, Oscar Arturo Migueles Lozano, Manuel Castillo Méndez, and Verónica Valverde-Garduño
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Medicine ,Science - Abstract
The innate immune response of Anopheles gambiae involves the transcriptional upregulation of effector genes. Therefore, the cis-regulatory sequences and their cognate binding factors play essential roles in the mosquito's immune response. However, the genetic control of the mosquito's innate immune response is not yet fully understood. To gain further insight on the elements, the factors and the potential mechanisms involved, an open chromatin profiling was carried out on A. gambiae-derived immune-responsive cells. Here, we report the identification of cis-regulatory sites, immunity-related transcription factor binding sites, and cis-regulatory modules. A de novo motif discovery carried out on this set of cis-regulatory sequences identified immunity-related motifs and cis-regulatory modules. These modules contain motifs that are similar to binding sites for REL-, STAT-, lola- and Deaf1-type transcription factors. Sequence motifs similar to the binding sites for GAGA were found within a cis-regulatory module, together with immunity-related transcription factor binding sites. The presence of Deaf1- and lola-type binding sites, along with REL- and STAT-type binding sites, suggests that the immunity function of these two factors could have been conserved both in Drosophila and Anopheles gambiae.
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- 2017
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28. Mutations in SORL1 and MTHFDL1 possibly contribute to the development of Alzheimer’s disease in a multigenerational Colombian Family
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Tejada Moreno, Johanna Alexandra, primary, Villegas Lanau, Andrés, additional, Madrigal Zapata, Lucia, additional, Baena Pineda, Ana Yulied, additional, Velez Hernandez, Juan, additional, Campo Nieto, Omer, additional, Soto Ospina, Alejandro, additional, Araque Marín, Pedronel, additional, Rishishwar, Lavanya, additional, Norris, Emily T., additional, Chande, Aroon T., additional, Jordan, I. King, additional, and Bedoya Berrio, Gabriel, additional
- Published
- 2022
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29. MicNet toolbox: Visualizing and unraveling a microbial network
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Favila, Natalia, primary, Madrigal-Trejo, David, additional, Legorreta, Daniel, additional, Sánchez-Pérez, Jazmín, additional, Espinosa-Asuar, Laura, additional, Eguiarte, Luis E., additional, and Souza, Valeria, additional
- Published
- 2022
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30. Early neurological development and nutritional status in Mexican socially deprived contexts
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Serván-Mori, Edson, primary, Fuentes-Rivera, Evelyn, additional, Quezada, Amado D., additional, Pineda-Antunez, Carlos, additional, del Carmen Hernández-Chávez, María, additional, García-Martínez, Angélica, additional, Madrigal, Abby, additional, García-Feregrino, Raquel, additional, Santiago-Angelino, Tania, additional, Hernández-Serrato, María, additional, and Schnaas, Lourdes, additional
- Published
- 2022
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31. Sexual and gender minority identity in undergraduate medical education: Impact on experience and career trajectory
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Madrigal, Josef, primary, Rudasill, Sarah, additional, Tran, Zachary, additional, Bergman, Jonathan, additional, and Benharash, Peyman, additional
- Published
- 2021
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32. MicNet toolbox: Visualizing and unraveling a microbial network
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Natalia Favila, David Madrigal-Trejo, Daniel Legorreta, Jazmín Sánchez-Pérez, Laura Espinosa-Asuar, Luis E. Eguiarte, and Valeria Souza
- Subjects
Multidisciplinary ,Microbiota ,Microbial Consortia ,Cluster Analysis ,Computational Biology ,Software - Abstract
Applications of network theory to microbial ecology are an emerging and promising approach to understanding both global and local patterns in the structure and interplay of these microbial communities. In this paper, we present an open-source python toolbox which consists of two modules: on one hand, we introduce a visualization module that incorporates the use of UMAP, a dimensionality reduction technique that focuses on local patterns, and HDBSCAN, a clustering technique based on density; on the other hand, we have included a module that runs an enhanced version of the SparCC code, sustaining larger datasets than before, and we couple the resulting networks with network theory analyses to describe the resulting co-occurrence networks, including several novel analyses, such as structural balance metrics and a proposal to discover the underlying topology of a co-occurrence network. We validated the proposed toolbox on 1) a simple and well described biological network of kombucha, consisting of 48 ASVs, and 2) we validate the improvements of our new version of SparCC. Finally, we showcase the use of the MicNet toolbox on a large dataset from Archean Domes, consisting of more than 2,000 ASVs. Our toolbox is freely available as a github repository (https://github.com/Labevo/MicNetToolbox), and it is accompanied by a web dashboard (http://micnetapplb-1212130533.us-east-1.elb.amazonaws.com) that can be used in a simple and straightforward manner with relative abundance data. This easy-to-use implementation is aimed to microbial ecologists with little to no experience in programming, while the most experienced bioinformatics will also be able to manipulate the source code’s functions with ease.
- Published
- 2021
33. Climatic Stress during Stand Development Alters the Sign and Magnitude of Age-Related Growth Responses in a Subtropical Mountain Pine.
- Author
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Paloma Ruiz-Benito, Jaime Madrigal-González, Sarah Young, Pierre Mercatoris, Liam Cavin, Tsurng-Juhn Huang, Jan-Chang Chen, and Alistair S Jump
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Medicine ,Science - Abstract
The modification of typical age-related growth by environmental changes is poorly understood, In part because there is a lack of consensus at individual tree level regarding age-dependent growth responses to climate warming as stands develop. To increase our current understanding about how multiple drivers of environmental change can modify growth responses as trees age we used tree ring data of a mountain subtropical pine species along an altitudinal gradient covering more than 2,200 m of altitude. We applied mixed-linear models to determine how absolute and relative age-dependent growth varies depending on stand development; and to quantify the relative importance of tree age and climate on individual tree growth responses. Tree age was the most important factor for tree growth in models parameterised using data from all forest developmental stages. Contrastingly, the relationship found between tree age and growth became non-significant in models parameterised using data corresponding to mature stages. These results suggest that although absolute tree growth can continuously increase along tree size when trees reach maturity age had no effect on growth. Tree growth was strongly reduced under increased annual temperature, leading to more constant age-related growth responses. Furthermore, young trees were the most sensitive to reductions in relative growth rates, but absolute growth was strongly reduced under increased temperature in old trees. Our results help to reconcile previous contrasting findings of age-related growth responses at the individual tree level, suggesting that the sign and magnitude of age-related growth responses vary with stand development. The different responses found to climate for absolute and relative growth rates suggest that young trees are particularly vulnerable under warming climate, but reduced absolute growth in old trees could alter the species' potential as a carbon sink in the future.
- Published
- 2015
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34. HLA Typing for the Next Generation.
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Neema P Mayor, James Robinson, Alasdair J M McWhinnie, Swati Ranade, Kevin Eng, William Midwinter, Will P Bultitude, Chen-Shan Chin, Brett Bowman, Patrick Marks, Henny Braund, J Alejandro Madrigal, Katy Latham, and Steven G E Marsh
- Subjects
Medicine ,Science - Abstract
Allele-level resolution data at primary HLA typing is the ideal for most histocompatibility testing laboratories. Many high-throughput molecular HLA typing approaches are unable to determine the phase of observed DNA sequence polymorphisms, leading to ambiguous results. The use of higher resolution methods is often restricted due to cost and time limitations. Here we report on the feasibility of using Pacific Biosciences' Single Molecule Real-Time (SMRT) DNA sequencing technology for high-resolution and high-throughput HLA typing. Seven DNA samples were typed for HLA-A, -B and -C. The results showed that SMRT DNA sequencing technology was able to generate sequences that spanned entire HLA Class I genes that allowed for accurate allele calling. Eight novel genomic HLA class I sequences were identified, four were novel alleles, three were confirmed as genomic sequence extensions and one corrected an existing genomic reference sequence. This method has the potential to revolutionize the field of HLA typing. The clinical impact of achieving this level of resolution HLA typing data is likely to considerable, particularly in applications such as organ and blood stem cell transplantation where matching donors and recipients for their HLA is of utmost importance.
- Published
- 2015
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35. Natural Killer Cells Improve Hematopoietic Stem Cell Engraftment by Increasing Stem Cell Clonogenicity In Vitro and in a Humanized Mouse Model.
- Author
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Michelle Escobedo-Cousin, Nicola Jackson, Raquel Laza-Briviesca, Linda Ariza-McNaughton, Martha Luevano, Sophie Derniame, Sergio Querol, Michael Blundell, Adrian Thrasher, Bernat Soria, Nichola Cooper, Dominique Bonnet, Alejandro Madrigal, and Aurore Saudemont
- Subjects
Medicine ,Science - Abstract
Cord blood (CB) is increasingly used as a source of hematopoietic stem cells (HSC) for transplantation. Low incidence and severity of graft-versus-host disease (GvHD) and a robust graft-versus-leukemia (GvL) effect are observed following CB transplantation (CBT). However, its main disadvantages are a limited number of HSC per unit, delayed immune reconstitution and a higher incidence of infection. Unmanipulated grafts contain accessory cells that may facilitate HSC engraftment. Therefore, the effects of accessory cells, particularly natural killer (NK) cells, on human CB HSC (CBSC) functions were assessed in vitro and in vivo. CBSC cultured with autologous CB NK cells showed higher levels of CXCR4 expression, a higher migration index and a higher number of colony forming units (CFU) after short-term and long-term cultures. We found that CBSC secreted CXCL9 following interaction with CB NK cells. In addition, recombinant CXCL9 increased CBSC clonogenicity, recapitulating the effect observed of CB NK cells on CBSC. Moreover, the co-infusion of CBSC with CB NK cells led to a higher level of CBSC engraftment in NSG mouse model. The results presented in this work offer the basis for an alternative approach to enhance HSC engraftment that could improve the outcome of CBT.
- Published
- 2015
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36. β-Catenin inactivation is a pre-requisite for chick retina regeneration.
- Author
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Jie Zhu, Agustin Luz-Madrigal, Tracy Haynes, Julia Zavada, Amy K Burke, and Katia Del Rio-Tsonis
- Subjects
Medicine ,Science - Abstract
In the present study we explored the role of β-catenin in mediating chick retina regeneration. The chick can regenerate its retina by activating stem/progenitor cells present in the ciliary margin (CM) of the eye or via transdifferentiation of the retinal pigmented epithelium (RPE). Both modes require fibroblast growth factor 2 (FGF2). We observed, by immunohistochemistry, dynamic changes of nuclear β-catenin in the CM and RPE after injury (retinectomy). β-Catenin nuclear accumulation was transiently lost in cells of the CM in response to injury alone, while the loss of nuclear β-catenin was maintained as long as FGF2 was present. However, nuclear β-catenin positive cells remained in the RPE in response to injury and were BrdU-/p27+, suggesting that nuclear β-catenin prevents those cells from entering the cell cycle. If FGF2 is present, the RPE undergoes dedifferentiation and proliferation concomitant with loss of nuclear β-catenin. Moreover, retinectomy followed by disruption of active β-catenin by using a signaling inhibitor (XAV939) or over-expressing a dominant negative form of Lef-1 induces regeneration from both the CM and RPE in the absence of FGF2. Our results imply that β-catenin protects cells of the CM and RPE from entering the cell cycle in the developing eye, and specifically for the RPE during injury. Thus inactivation of β-catenin is a pre-requisite for chick retina regeneration.
- Published
- 2014
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37. The effects of CAMPATH-1H on cell viability do not correlate to the CD52 density on the cell surface.
- Author
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Fuiyee Lee, Martha Luevano, Paul Veys, Kwee Yong, Alejandro Madrigal, Bronwen E Shaw, and Aurore Saudemont
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Medicine ,Science - Abstract
Graft versus host disease (GvHD) is one of the main complications after hematological stem cell transplantation (HSCT). CAMPATH-1H is used in the pre-transplant conditioning regimen to effectively reduce GvHD by targeting CD52 antigens on T cells resulting in their depletion. Information regarding CD52 expression and the effects of CAMPATH-1H on immune cells is scant and limited to peripheral blood (PB) T and B cells. To date, the effects of CAMPATH-1H on cord blood (CB) cells has not been studied. Here we aimed to analyze CD52 expression and the effects of CAMPATH-1H on fresh or frozen, resting or activated, PB mononuclear cells (PBMC) and CB mononuclear cells (CBMC). In resting state, CD52 expression was higher in CB than PB T cell subsets (653.66 ± 26.68 vs 453.32 ± 19.2) and B cells (622.2±20.65 vs 612.0 ± 9.101) except for natural killer (NK) cells where CD52 levels were higher in PB (421.0 ± 9.857) than CB (334.3 ± 9.559). In contrast, CD52 levels were comparable across all cell types after activation. CAMPATH-1H depleted resting cells more effectively than activated cells with approximately 80-95% of apoptosis observed with low levels of necrosis. There was no direct correlation between cell surface CD52 density and depleting effects of CAMPATH-1H. In addition, no difference in cell viability was noted when different concentrations of CAMPATH-1H were used. CD52 was not expressed on HSC but began to be expressed as the cells differentiate, implying that CAMPATH-1H could potentially affect HSC differentiation and proliferation. Our study provides insightful information, which contributes to the better understanding in the use of CAMPATH-1H as part of the conditioning regime in HSCT.
- Published
- 2014
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38. Frozen cord blood hematopoietic stem cells differentiate into higher numbers of functional natural killer cells in vitro than mobilized hematopoietic stem cells or freshly isolated cord blood hematopoietic stem cells.
- Author
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Martha Luevano, Anna Domogala, Michael Blundell, Nicola Jackson, Isabela Pedroza-Pacheco, Sophie Derniame, Michelle Escobedo-Cousin, Sergio Querol, Adrian Thrasher, Alejandro Madrigal, and Aurore Saudemont
- Subjects
Medicine ,Science - Abstract
Adoptive natural killer (NK) cell therapy relies on the acquisition of large numbers of NK cells that are cytotoxic but not exhausted. NK cell differentiation from hematopoietic stem cells (HSC) has become an alluring option for NK cell therapy, with umbilical cord blood (UCB) and mobilized peripheral blood (PBCD34(+)) being the most accessible HSC sources as collection procedures are less invasive. In this study we compared the capacity of frozen or freshly isolated UCB hematopoietic stem cells (CBCD34(+)) and frozen PBCD34(+) to generate NK cells in vitro. By modifying a previously published protocol, we showed that frozen CBCD34(+) cultures generated higher NK cell numbers without loss of function compared to fresh CBCD34(+) cultures. NK cells generated from CBCD34(+) and PBCD34(+) expressed low levels of killer-cell immunoglobulin-like receptors but high levels of activating receptors and of the myeloid marker CD33. However, blocking studies showed that CD33 expression did not impact on the functions of the generated cells. CBCD34(+)-NK cells exhibited increased capacity to secrete IFN-γ and kill K562 in vitro and in vivo as compared to PBCD34(+)-NK cells. Moreover, K562 killing by the generated NK cells could be further enhanced by IL-12 stimulation. Our data indicate that the use of frozen CBCD34(+) for the production of NK cells in vitro results in higher cell numbers than PBCD34(+), without jeopardizing their functionality, rendering them suitable for NK cell immunotherapy. The results presented here provide an optimal strategy to generate NK cells in vitro for immunotherapy that exhibit enhanced effector function when compared to alternate sources of HSC.
- Published
- 2014
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39. Sexual and gender minority identity in undergraduate medical education: Impact on experience and career trajectory
- Author
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Sarah E. Rudasill, Peyman Benharash, Josef Madrigal, Jonathan Bergman, and Zachary Tran
- Subjects
Students, Medical ,Cross-sectional study ,Economics ,Social Sciences ,Surveys ,Sexual and Gender Minorities ,Pediatric Surgery ,Sociology ,Medicine and Health Sciences ,Psychology ,Suicidal ideation ,Minority Groups ,media_common ,Response rate (survey) ,Multidisciplinary ,Careers ,Gender Identity ,Research Design ,Test score ,Scale (social sciences) ,Educational Status ,Medicine ,medicine.symptom ,Clinical psychology ,Education, Medical, Undergraduate ,Research Article ,Adult ,Employment ,media_common.quotation_subject ,Science ,Specialty ,Surgical and Invasive Medical Procedures ,Affect (psychology) ,Research and Analysis Methods ,Specialties, Surgical ,Suicidal Ideation ,Education ,medicine ,Humans ,Survey Research ,Bullying ,Biology and Life Sciences ,Trainees ,Cross-Sectional Studies ,Medical Education ,Labor Economics ,People and Places ,Population Groupings ,Medical Humanities ,Undergraduates ,Diversity (politics) - Abstract
Introduction The wellbeing of sexual and gender minority (SGM) medical students and the impact of their experiences on career trajectory remain poorly understood. The present study aimed to characterize the incidence of mistreatment in SGM trainees as well as general perspectives on the acceptance of SGM individuals across medical and surgical specialties. Methods This was a cross sectional survey study of all actively enrolled medical students within the six University of California campuses conducted in March 2021. An online, survey tool captured incidence of bullying, discrimination, and suicidal ideation as well as perceived acceptance of SGM identities across specialties measured by slider scale. Differences between SGM and non-SGM respondents were assessed with two-tailed and chi-square tests. Qualitative responses were evaluated utilizing a multi-stage, cutting-and-sorting technique. Results Of approximately 3,205 students eligible for participation, 383 submitted completed surveys, representing a response rate of 12.0%. Of these respondents, 26.9% (n = 103) identified as a sexual or gender minority. Overall, SGM trainees reported higher slider scale scores when asked about being bullied by other students (20.0 vs. 13.9, P = 0.012) and contemplating suicide (14.8 vs. 8.8, P = 0.005). Compared to all other specialties, general surgery and surgical subspecialties had the lowest mean slider scale score (52.8) in perceived acceptance of SGM identities (All P < 0.001). In qualitative responses, students frequently cited lack of diversity as contributing to this perception. Additionally, 67.0% of SGM students had concerns that disclosure of identity would affect their future career with 18.5% planning to not disclose during the residency application process. Conclusions Overall, SGM respondents reported higher incidences of bullying and suicidal ideation as well as increased self-censorship stemming from concerns regarding career advancement, most prominently in surgery. To address such barriers, institutions must actively promote diversity in sexual preference and gender identity regardless of specialty.
- Published
- 2021
40. CCR2/CCL2 and CMKLR1/RvE1 chemokines system levels are associated with insulin resistance in rheumatoid arthritis
- Author
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Felipe Perez-Vazquez, Mónica Vázquez-Del Mercado, Luis-Javier Flores-Alvarado, Fernanda-Isadora Corona-Meraz, Jesus-Aureliano Robles-De Anda, Eduardo Gómez-Bañuelos, Jorge Castro-Albarrán, Rosa Elena Navarro-Hernández, Perla-Monserrat Madrigal-Ruíz, Oscar-Enrique Pizano-Martínez, and Gustavo Ignacio Diaz-Rubio
- Subjects
Male ,CCR2 ,Physiology ,medicine.medical_treatment ,Adipose tissue ,White adipose tissue ,Biochemistry ,Body Mass Index ,Arthritis, Rheumatoid ,Endocrinology ,Medicine and Health Sciences ,Insulin ,Immune Response ,Chemokine CCL2 ,Adiposity ,Multidisciplinary ,Chemistry ,Chemotaxis ,Middle Aged ,Cell Motility ,Adipose Tissue ,Physiological Parameters ,Eicosapentaenoic Acid ,Connective Tissue ,Medicine ,Female ,Receptors, Chemokine ,medicine.symptom ,Anatomy ,Chemokines ,Research Article ,Adult ,medicine.medical_specialty ,Adolescent ,Receptors, CCR2 ,Science ,Immunology ,Inflammation ,Context (language use) ,Rheumatoid Arthritis ,CCL2 ,Autoimmune Diseases ,Young Adult ,Insulin resistance ,Signs and Symptoms ,Rheumatology ,Internal medicine ,medicine ,Humans ,Obesity ,Diabetic Endocrinology ,Endocrine Physiology ,Arthritis ,Body Weight ,Biology and Life Sciences ,Cell Biology ,medicine.disease ,Hormones ,Biological Tissue ,Cross-Sectional Studies ,Clinical Immunology ,Clinical Medicine ,Insulin Resistance - Abstract
Rheumatoid arthritis (RA) has been associated with insulin resistance (IR). Due to an excess in storage of white adipose tissue, IR has an inflammatory process that overlaps with RA. This is performed by the activation/migration of monocytes carried out by the CCR2/CCL2 and CMKLR1/RvE1 chemokines systems. Furthermore, these can potentiate chronic inflammation which is the central axis in the immunopathogenesis of RA. We evaluated the association between the relative expression of CCR2 and CMKLR1 and the serum levels of their ligands CCL2 and RvE1, in the context of adiposity status with IR as a comorbidity in RA. We studied 138 controls and 138 RA-patients classified with and without IR. We evaluated adiposity, RA activity, IR status and immunometabolic profiles by routine methods. Insulin, CCL2 and RvE1 serum levels were determined by ELISA. Relative expression of CCR2, CMKLR1 and RPS28 as constitutive gene by SYBR green RT-qPCR and 2-ΔΔCT method. Increased measurements were observed of body adiposity and metabolic status as follows: RA with IR>control group with IR>RA without IR> control group without IR. CCR2 and CMKLR1 relative expression was increased in RA without IR versus control without IR. CCR2: 2.3- and 1.3-fold increase and CMKLR1: 3.5- and 2.7-fold increase, respectively. Whereas, CCR2 expression correlates with CMKLR1 expression (rho = 0.331) and IR status (rho = 0.497 to 0.548). CMKLR1 expression correlates with inflammation markers (rho = 0.224 to 0.418). CCL2 levels were increased in the RA groups but levels of RvE1 were increased in RA without IR. We conclude that in RA with IR, the chemokine receptors expression pattern showed a parallel increase with their respective ligands. RA and IR in conjunction with the pathological distribution of body fat mass might exacerbate chronic inflammation. These results suggest that high CCL2 levels and compensatory RvE1 levels might not be enough to resolve the inflammation by themselves.
- Published
- 2021
41. The masked seducers: Lek courtship behavior in the wrinkle-faced bat Centurio senex (Phyllostomidae)
- Author
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Daniel Zamora-Mejías, Gloria Gessinger, Paulina Rodríguez, Marco Tschapka, Esteban Hernández, Ricardo Sánchez-Calderón, Bernal Rodríguez-Herrera, Victor Madrigal-Elizondo, and Jairo Villalobos
- Subjects
Male ,Animal sexual behaviour ,Video Recording ,Social Sciences ,Courtship ,Vocalization ,Sexual Behavior, Animal ,Animal Wings ,Chiroptera ,Bats ,Copulation ,Medicine and Health Sciences ,Psychology ,Mating ,Animal Anatomy ,media_common ,Mammals ,Sex Characteristics ,Multidisciplinary ,biology ,Animal Behavior ,Eukaryota ,Vertebrates ,Medicine ,Female ,Anatomy ,Behavior Observation Techniques ,Research Article ,Costa Rica ,media_common.quotation_subject ,Science ,Zoology ,Human echolocation ,Animal Sexual Behavior ,Frugivore ,Animals ,Behavior ,Courtship display ,Organisms ,Biology and Life Sciences ,Centurio senex ,biology.organism_classification ,Sexual dimorphism ,Animal Communication ,Echolocation ,Face ,Amniotes ,Mating Behavior ,Head - Abstract
Centurio senexis an iconic bat characterized by a facial morphology deviating far from all other New World Leaf Nosed Bats (Phyllostomidae). The species has a bizarrely wrinkled face and lacks the characteristic nose leaf. Throughout its distribution from Mexico to Northern South America the species is most of the time rarely captured and only scarce information on its behavior and natural history is available.Centurio senexis frugivorous and one of the few bats documented to consume also hard seeds. Interestingly, the species shows a distinct sexual dimorphism: Adult males have more pronounced facial wrinkles than females and a fold of skin under the chin that can be raised in style of a face mask. We report the first observations on echolocation and mating behavior ofCenturio senex, including synchronized audio and video recordings from an aggregation of males in Costa Rica. Over a period of 6 weeks we located a total of 53 perches, where during the first half of the night males were hanging with raised facial masks at a mean height of 2.35 m. Most of the time, the males moved just their wing tips, and spontaneously vocalized in the ultrasound range. Approaches of other individuals resulted in the perching male beating its wings and emitting a very loud, low frequency whistling call. Following such an encounter we recorded a copulation event. The observed aggregation of adultC.senexmales is consistent with lek courtship, a behavior described from only few other bat species.
- Published
- 2020
42. Cord blood Lin(-)CD45(-) embryonic-like stem cells are a heterogeneous population that lack self-renewal capacity.
- Author
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Cesar Alvarez-Gonzalez, Richard Duggleby, Barbora Vagaska, Sergio Querol, Susana G Gomez, Patrizia Ferretti, and Alejandro Madrigal
- Subjects
Medicine ,Science - Abstract
Human umbilical cord blood (hUCB) has been proposed to contain not only haematopoietic stem cells, but also a rare pluripotent embryonic-like stem cell (ELSc) population that is negative for hematopoietic markers (Lin(-)CD45(-)) and expresses markers typical of pluripotent cells. The aim of this work was to isolate, characterise and expand this ELSc fraction from hUCB, as it may provide a valuable cell source for regenerative medicine applications. We found that we could indeed isolate a Lin(-)CD45(-) population of small cells (3-10 µm diameter) with a high nucleus to cytoplasm ratio that expressed the stem cell markers CD34 and CXCR4. However, in contrast to some previous reports, this fraction was not positive for CD133. Furthermore, although these cells expressed transcripts typical of pluripotent cells, such as SOX2, OCT3/4, and NANOG, they were not able to proliferate in any of the culture media known to support stem cell growth that we tested. Further analysis of the Lin(-)CD45(-) population by flow cytometry showed the presence of a Lin(-)CD45(-)Nestin(+) population that were also positive for CD34 (20%) but negative for CXCR4. These data suggest that the Lin(-)CD45(-) stem cell fraction present in the cord blood represents a small heterogeneous population with phenotypic characteristics of stem cells, including a Lin(-)CD45(-)Nestin(+) population not previously described. This study also suggests that heterogeneity within the Lin(-)CD45(-) cell fraction is the likely explanation for differences in the hUCB cell populations described by different groups that were isolated using different methods. These populations have been widely called "embryonic-like stem cell" on the basis of their phenotypical similarity to embryonic stem cells. However, the fact they do not seem to be able to self-renew casts some doubt on their identity, and warns against defining them as "embryonic-like stem cell" at this stage.
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- 2013
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43. How does Tremblaya princeps get essential proteins from its nested partner Moranella endobia in the Mealybug Planoccocus citri?
- Author
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Sergio López-Madrigal, Séverine Balmand, Amparo Latorre, Abdelaziz Heddi, Andrés Moya, and Rosario Gil
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Medicine ,Science - Abstract
Many insects maintain intracellular mutualistic symbiosis with a wide range of bacteria which are considered essential for their survival (primary or P-endosymbiont) and typically suffer drastic genome degradation. Progressive loss of P-endosymbiont metabolic capabilities could lead to the recruitment of co-existent facultative endosymbiont (secondary or S-endosymbiont), thus adding more complexity to the symbiotic system. Planococcus citri, among other mealybug species, harbors an unconventional nested endosymbiotic system where every Tremblaya princeps cell (β-proteobacterium) harbors many Moranella endobia cells (γ-proteobacterium). In this system, T. princeps possess one of the smallest prokaryote genome known so far. This extreme genome reduction suggests the supply of many metabolites and essential gene products by M. endobia. Although sporadic cell lysis is plausible, the bacterial participation on the regulation of the predicted molecular exchange (at least to some extent) cannot be excluded. Although the comprehensive analysis of the protein translocation ability of M. endobia PCVAL rules out the existence of specific mechanisms for the exportation of proteins from M. endobia to T. princeps, immunolocation of two M. endobia proteins points towards a non-massive but controlled protein provision. We propose a sporadic pattern for the predicted protein exportation events, which could be putatively controlled by the host and/or mediated by local osmotic stress.
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- 2013
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44. Scattering of light by colloidal aluminosilicate particles produces the unusual sky-blue color of Río Celeste (Tenorio volcano complex, Costa Rica).
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Erick Castellón, María Martínez, Sergio Madrigal-Carballo, María Laura Arias, William E Vargas, and Max Chavarría
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Medicine ,Science - Abstract
Río Celeste (Sky-Blue River) in Tenorio National Park (Costa Rica), a river that derives from the confluence and mixing of two colorless streams--Río Buenavista (Buenavista River) and Quebrada Agria (Sour Creek)--is renowned in Costa Rica because it presents an atypical intense sky-blue color. Although various explanations have been proposed for this unusual hue of Río Celeste, no exhaustive tests have been undertaken; the reasons hence remain unclear. To understand this color phenomenon, we examined the physico-chemical properties of Río Celeste and of the two streams from which it is derived. Chemical analysis of those streams with ion-exchange chromatography (IC) and inductively coupled plasma atomic emission spectroscopy (ICP-OES) made us discard the hypothesis that the origin of the hue is due to colored chemical species. Our tests revealed that the origin of this coloration phenomenon is physical, due to suspended aluminosilicate particles (with diameters distributed around 566 nm according to a lognormal distribution) that produce Mie scattering. The color originates after mixing of two colorless streams because of the enlargement (by aggregation) of suspended aluminosilicate particles in the Río Buenavista stream due to a decrease of pH on mixing with the acidic Quebrada Agria. We postulate a chemical mechanism for this process, supported by experimental evidence of dynamic light scattering (DLS), zeta potential measurements, X-ray diffraction and scanning electron microscopy (SEM) with energy-dispersive spectra (EDS). Theoretical modeling of the Mie scattering yielded a strong coincidence between the observed color and the simulated one.
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- 2013
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45. Sperm kinematic subpopulations of the American crocodile (Crocodylus acutus)
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Valverde, Anthony, primary, Castro-Morales, Olivier, additional, Madrigal-Valverde, Mónica, additional, Camacho, Marlen, additional, Barquero, Vinicio, additional, Soler, Carles, additional, and Roldan, Eduardo R. S., additional
- Published
- 2021
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46. Enumerating regulatory T cells in cryopreserved umbilical cord blood samples using FOXP3 methylation specific quantitative PCR
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J. Alejandro Madrigal, Richard C. Duggleby, Kathryn Strange, A.J. McWhinnie, Diana Hernandez, David J. Roberts, Robert Danby, Abigail A. Lamikanra, and Hoi Pat Tsang
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0301 basic medicine ,Physiology ,Biochemistry ,T-Lymphocytes, Regulatory ,Umbilical cord ,Cryopreservation ,Spectrum Analysis Techniques ,0302 clinical medicine ,Cellular types ,DNA methylation ,Sex Chromosomes ,Multidisciplinary ,Cell Death ,medicine.diagnostic_test ,Immune cells ,FOXP3 ,X Chromosomes ,Forkhead Transcription Factors ,Regulatory T cells ,Flow Cytometry ,Fetal Blood ,Chromatin ,Body Fluids ,Nucleic acids ,Blood ,medicine.anatomical_structure ,Real-time polymerase chain reaction ,Spectrophotometry ,Cell Processes ,030220 oncology & carcinogenesis ,White blood cells ,Medicine ,Epigenetics ,Cytophotometry ,Cord Blood Stem Cell Transplantation ,Anatomy ,DNA modification ,Chromatin modification ,Research Article ,Chromosome biology ,Cell biology ,Blood cells ,Science ,Immunology ,T cells ,Human leukocyte antigen ,Biology ,Research and Analysis Methods ,Chromosomes ,Flow cytometry ,Andrology ,03 medical and health sciences ,Genetics ,medicine ,Humans ,Medicine and health sciences ,Biology and life sciences ,DNA ,Transplantation ,030104 developmental biology ,Animal cells ,Blood Preservation ,Gene expression - Abstract
BackgroundAllogeneic haematopoietic cell transplantation (HCT) is a curative therapy for severe haematological disorders. However, it carries significant risk of morbidity and mortality. To improve patient outcomes, better graft selection strategies are needed, incorporating HLA matching with clinically important graft characteristics. Studies have shown that the cellular content of HCT grafts, specifically higher ratios of T regulatory (Tregs)/T cells, are important factors influencing outcomes when using adult peripheral blood mobilised grafts. So far, no equivalent study exists in umbilical cord blood (CB) transplantation due to the limitations of cryopreserved CB samples.Study design and methodsTo establish the most robust and efficient way to measure the Treg content of previously cryopreserved CB units, we compared the enumeration of Treg and CD3+ cells using flow cytometry and an epigenetic, DNA-based methodology. The two methods were assessed for their agreement, consistency and susceptibility to error when enumerating Treg and CD3+ cell numbers in both fresh and cryopreserved CB samples.ResultsEpigenetic enumeration gave consistent and comparable results in both fresh and frozen CB samples. By contrast, assessment of Tregs and CD3+ cells by flow cytometry was only possible in fresh samples due to significant cell death following cryopreservation and thawing.ConclusionEpigenetic assessment offers significant advantages over flow cytometry for analysing cryopreserved CB; similar cell numbers were observed both in fresh and frozen samples. Furthermore, multiple epigenetic assessments can be performed from DNA extracted from small cryopreserved CB segments; often the only CB sample available for clinical studies.
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- 2020
47. Turning off the tap: Common domestic water conservation actions insufficient to alleviate drought in the United States of America
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Donald A. Croll, Heather Tallis, Bernie R. Tershy, and Diana Madrigal Ruiz
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Atmospheric Science ,Environmental Engineering ,Water Management ,010504 meteorology & atmospheric sciences ,Natural resource economics ,Climate Change ,Rain ,Science ,0207 environmental engineering ,Water supply ,Crops ,02 engineering and technology ,01 natural sciences ,Geographical locations ,Water conservation ,Meteorology ,Water Supply ,Surface Water ,Natural Resources ,Farm water ,Incentive program ,020701 environmental engineering ,0105 earth and related environmental sciences ,Conservation of Water Resources ,Multidisciplinary ,Drought ,business.industry ,Ecology and Environmental Sciences ,Biology and Life Sciences ,Agriculture ,United States ,Droughts ,Water resources ,Incentive ,North America ,Water Resources ,Earth Sciences ,Engineering and Technology ,Medicine ,People and places ,Hydrology ,business ,Water use ,Research Article ,Crop Science - Abstract
Climate change is exacerbating drought and water stress in several global regions, including some parts of the United States. During times of drought in the U.S., municipal governments, private water suppliers and non-profits commonly deploy advocacy campaigns and incentive programs targeting reductions in residential water use through actions including: repairing leaks, shutting off taps, and installing new water-saving appliances. We asked whether these campaigns have the potential to alleviate water stress during drought at the county scale by estimating the potential impact of full adoption of such actions. In 2010, we show that the maximum potential use reductions from these residential actions may only alleviate water stress in 6% (174) of U.S. counties. The potential impact of domestic programs is limited by the relative dominance of agriculture water withdrawal, the primary water user in 50% of U.S. counties. While residential actions do achieve some water demand savings, they are not sufficient to alter water stress in the majority of the continental U.S. We recommend redirecting advocacy efforts and incentives to individual behaviors that can influence agricultural water use.
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- 2020
48. CCR2/CCL2 and CMKLR1/RvE1 chemokines system levels are associated with insulin resistance in rheumatoid arthritis
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Diaz-Rubio, Gustavo Ignacio, primary, Corona-Meraz, Fernanda-Isadora, additional, Madrigal-Ruiz, Perla-Monserrat, additional, Robles-De Anda, Jesús-Aureliano, additional, Gómez-Bañuelos, Eduardo, additional, Castro-Albarran, Jorge, additional, Flores-Alvarado, Luis-Javier, additional, Vázquez-Del Mercado, Mónica, additional, Pérez-Vázquez, Felipe de Jesús, additional, Pizano-Martínez, Oscar-Enrique, additional, and Navarro-Hernández, Rosa-Elena, additional
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- 2021
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49. The masked seducers: Lek courtship behavior in the wrinkle-faced bat Centurio senex (Phyllostomidae)
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Rodríguez-Herrera, Bernal, primary, Sánchez-Calderón, Ricardo, additional, Madrigal-Elizondo, Victor, additional, Rodríguez, Paulina, additional, Villalobos, Jairo, additional, Hernández, Esteban, additional, Zamora-Mejías, Daniel, additional, Gessinger, Gloria, additional, and Tschapka, Marco, additional
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- 2020
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50. Effects of algal diversity on the production of biomass in homogeneous and heterogeneous nutrient environments: a microcosm experiment.
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Jerome J Weis, Daniel S Madrigal, and Bradley J Cardinale
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Medicine ,Science - Abstract
One of the most common questions addressed by ecologists over the past decade has been--how does species richness impact the production of community biomass? Recent summaries of experiments have shown that species richness tends to enhance the production of biomass across a wide range of trophic groups and ecosystems; however, the biomass of diverse polycultures only rarely exceeds that of the single most productive species in a community (a phenomenon called 'transgressive overyielding'). Some have hypothesized that the lack of transgressive overyielding is because experiments have generally been performed in overly-simplified, homogeneous environments where species have little opportunity to express the niche differences that lead to 'complementary' use of resources that can enhance biomass production. We tested this hypothesis in a laboratory experiment where we manipulated the richness of freshwater algae in homogeneous and heterogeneous nutrient environments.Experimental units were comprised of patches containing either homogeneous nutrient ratios (16:1 nitrogen to phosphorus (N:P) in all patches) or heterogeneous nutrient ratios (ranging from 4:1 to 64:1 N:P across patches). After allowing 6-10 generations of algal growth, we found that algal species richness had similar impacts on biomass production in both homo- and heterogeneous environments. Although four of the five algal species showed a strong response to nutrient heterogeneity, a single species dominated algal communities in both types of environments. As a result, a 'selection effect'--where diversity maximizes the chance that a competitively superior species will be included in, and dominate the biomass of a community--was the primary mechanism by which richness influenced biomass in both homo- and heterogeneous environments.Our study suggests that spatial heterogeneity, by itself, is not sufficient to generate strong effects of biodiversity on productivity. Rather, heterogeneity must be coupled with variation in the relative fitness of species across patches in order for spatial niche differentiation to generate complementary resource use.
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- 2008
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