24 results on '"Villalobos, A."'
Search Results
2. DENV-2 Outbreak Associated With Cosmopolitan Genotype Emergence in Western Brazilian Amazon.
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Ribeiro, Jessiane Rodrigues, Roca, Tárcio Peixoto, Cartonilho, Gleense dos Santos, Passos-Silva, Ana Maísa, Moreira, Hillquias Monteiro, Teixeira, Karolaine Santos, da Silva, André Luiz Ferreira, Lugtenburg, Celina Aparecida Bertoni, dos Santos, Alcione Oliveira, Villalobos Salcedo, Juan Miguel, do Nascimento, Valdinete Alves, de Souza, Victor Costa, Roque, Rosemary Aparecida, Krieger, Marco Aurélio, Naveca, Felipe Gomes, Rampazzo, Rita de Cássia Pontello, and Vieira, Deusilene Souza
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GENOTYPES ,DENGUE viruses ,SEQUENCE analysis ,CHIKUNGUNYA ,ARBOVIRUSES - Abstract
Background: Dengue virus (DENV) causes an important disease and directly affects public health, being the arbovirus that presents the highest number of infections and deaths in the Western Brazilian Amazon. This virus is divided into 4 serotypes that have already circulated in the region. Methodology: Molecular characterization of a cohort containing 841 samples collected from febrile patients between 2021 and 2023 was analyzed using a commercial kit to detect the main arboviruses circulating in Brazil: Zika, DENV-1, DENV-2, DENV-3, DENV-4 and, Chikungunya. Subsequently, Sanger sequencing was performed for positive samples. Results: The cohort detected 162 positive samples, 12 for DENV-1 and 150 identified as DENV-2, indicating co-circulation of serotypes. The samples were subjected to sequencing and the analysis of the sequences that obtained good quality revealed that 5 samples belonged to the V genotype of DENV-1 and 46 were characterized as DENV-2 Cosmopolitan genotype—lineage 5. Conclusion: The results allowed us to identify for the first time the Cosmopolitan genotype in Rondônia, Brazilian Western Amazon, and its fast spread dispersion. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Multicenter study of the natural history and therapeutic responses of patients with chikungunya, focusing on acute and chronic musculoskeletal manifestations – a study protocol from the clinical and applied research in Chikungunya (REPLICK network).
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da Silva Duarte, Giselle, Jones, Alexandra D., de Goes Cavalcanti, Luciano Pamplona, de Melo Rêgo, Moacyr Jesus Barreto, Ribeiro, Guilherme S., Boyton, Rosemary J., Pereira, Dhelio Batista, Croda, Julio Henrique Rosa, Costa, Fabio Trindade Maranhão, Duarte, Angela Pinto, Consolaro, Marcia Edilaine Lopes, Stabeli, Rodrigo Guerino, Negrão, Fábio Juliano, Proenca-Modena, Jose Luiz, Villalobos-Salcedo, Juan Miguel, da Rocha Castelar Pinheiro, Geraldo, de Barros Albuquerque, Amanda Pinheiro, de Almeida Barreto, Francisca Kalline, Moreira, Jose, and Ferrari, Idalina Cristina
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MEDICAL research ,JOINT pain ,CHIKUNGUNYA ,RESEARCH protocols ,MUSCULOSKELETAL system diseases ,MEDICAL protocols - Abstract
Background: Chikungunya is associated with high morbidity and the natural history of symptomatic infection has been divided into three phases (acute, post-acute, and chronic) according to the duration of musculoskeletal symptoms. Although this classification has been designed to help guide therapeutic decisions, it does not encompass the complexity of the clinical expression of the disease and does not assist in the evaluation of the prognosis of severity nor chronic disease. Thus, the current challenge is to identify and diagnose musculoskeletal disorders and to provide the optimal treatment in order to prevent perpetuation or progression to a potentially destructive disease course. Methods: The study is the first product of the Clinical and Applied Research Network in Chikungunya (REPLICK). This is a prospective, outpatient department-based, multicenter cohort study in Brazil. Four work packages were defined: i. Clinical research; ii) Translational Science – comprising immunology and virology streams; iii) Epidemiology and Economics; iv) Therapeutic Response and clinical trials design. Scheduled appointments on days 21 (D21) ± 7 after enrollment, D90 ± 15, D120 ± 30, D180 ± 30; D360 ± 30; D720 ± 60, and D1080 ± 60 days. On these visits a panel of blood tests are collected in addition to the clinical report forms to obtain data on socio-demographic, medical history, physical examination and questionnaires devoted to the evaluation of musculoskeletal manifestations and overall health are performed. Participants are asked to consent for their specimens to be maintained in a biobank. Aliquots of blood, serum, saliva, PAXgene, and when clinically indicated to be examined, synovial fluid, are stored at -80° C. The study protocol was submitted and approved to the National IRB and local IRB at each study site. Discussion: Standardized and harmonized patient cohorts are needed to provide better estimates of chronic arthralgia development, the clinical spectra of acute and chronic disease and investigation of associated risk factors. This study is the largest evaluation of the long-term sequelae of individuals infected with CHIKV in the Brazilian population focusing on musculoskeletal manifestations, mental health, quality of life, and chronic pain. This information will both define disease burden and costs associated with CHIKV infection, and better inform therapeutic guidelines. [ABSTRACT FROM AUTHOR]
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- 2023
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4. Systemic Inflammatory Molecules Are Associated with Advanced Fibrosis in Patients from Brazil Infected with Hepatitis Delta Virus Genotype 3 (HDV-3).
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Souza Campos, Mauricio, Villalobos-Salcedo, Juan Miguel, Vieira Dallacqua, Deusilene Souza, Lopes Borges Andrade, Caio, Meyer Nascimento, Roberto José, Menezes Freire, Songeli, Paraná, Raymundo, and Schinoni, Maria Isabel
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HEPATITIS D virus ,ASPARTATE aminotransferase ,RESTRICTION fragment length polymorphisms ,FIBROSIS ,HEPATITIS B virus ,HEPATITIS D - Abstract
Background and Aims: Hepatitis Delta virus (HDV) genotype 3 is responsible for outbreaks of fulminant hepatitis in Northeastern South America. This study investigates if systemic inflammatory molecules are differentially expressed in patients with advanced fibrosis chronically infected with Hepatitis Delta virusgenotype 3(HDV-3). Methods: Sixty-one patients from the north of Brazil coinfected with hepatitis B virus (HBV)/HDV-3 were analyzed. HDV quantification and genotyping were performed by semi-nested real-time polymerase chain reaction (RT-PCR) and restriction fragment length polymorphism (RFLP) methodologies. Ninety-two systemic inflammatory molecules (SIMs) were measured by Proximity Extension Assay (PEA) technology. The Shapiro–Wilk, Student's t-test, Mann–Whitney tests, and logistic regression analysis were used when appropriate. Results: The median age was 41 years, and all patients were HBeAg negative. Advanced fibrosis or cirrhosis was diagnosed by histological staging in 17 patients, while 44 presented with minimal or no fibrosis. Advanced necroinflammatory activity correlated positively with serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Established non-invasive fibrosis scores (APRI, FIB-4, and AST/ALT ratio) revealed low sensitivities and positive predictive values (PPVs) with an AUROC maximum of 0.586. Among the 92 SIMs analyzed, MCP.4, CCL19, EN.RAGE, SCF, and IL18 showed a positive correlation with fibrosis stage. A combined score including CCL19 and MCP.4 revealed a sensitivity of 81% and an odds ratio of 2.202 for advanced fibrosis. Conclusions: Standard non-invasive fibrosis scores showed poor performance in HDV-3 infection. We here suggest that the determination of CCL19 and MCP.4 may be used to identify patients with advanced fibrosis. Moreover, this study gives novel insights into the immunopathogenesis of HDV-3 infection. [ABSTRACT FROM AUTHOR]
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- 2023
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5. Papilionidae de la Colección de Entomología del Museo de Historia Natural (MHN-UniCauca), Popayán, Cauca, Colombia (Insecta: Lepidoptera).
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Gallego-Ropero, María Cristina, Villalobos-Moreno, Alfonso, Patricia Gallego-López, Ángela, and Salazar, Julián A.
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NATURAL history museums ,BIOMATERIALS ,PAPILIONIDAE ,SUBSPECIES ,SPECIES ,PERCENTILES - Abstract
Copyright of SHILAP Revista de Lepidopterologia is the property of Sociedad Hispano-Luso-Americana de Lepidopterologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2023
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6. Screening for Severe Acute Respiratory Syndrome Coronavirus 2 in Close Contacts of Individuals With Confirmed Infection: Performance and Operational Considerations.
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Zobrist, Stephanie, Oliveira-Silva, Michelle, Vieira, Alexia Martines, Bansil, Pooja, Gerth-Guyette, Emily, Leader, Brandon T, Golden, Allison, Slater, Hannah, Cruz, Catherine Duran de Lucena, Garbin, Eduardo, Sagalovsky, Mariana, Pal, Sampa, Gupta, Vin, Wolansky, Leo, Dall'Acqua, Deusilene Souza Vieira, Naveca, Felipe Gomes, Nascimento, Valdinete Alves do, Salcedo, Juan Miguel Villalobos, Drain, Paul K, and Costa, Alexandre Dias Tavares
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SARS-CoV-2 ,CORONAVIRUS diseases ,MEDICAL screening ,COVID-19 ,SARS-CoV-2 Delta variant ,ANTIGEN analysis - Abstract
Background Point-of-care and decentralized testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical to inform public health responses. Performance evaluations in priority use cases such as contact tracing can highlight trade-offs in test selection and testing strategies. Methods A prospective diagnostic accuracy study was conducted among close contacts of coronavirus disease 2019 (COVID-19) cases in Brazil. Two anterior nares swabs (ANS), a nasopharyngeal swab (NPS), and saliva were collected at all visits. Vaccination history and symptoms were assessed. Household contacts were followed longitudinally. Three rapid antigen tests and 1 molecular method were evaluated for usability and performance against reference reverse-transcription polymerase chain reaction (RT-PCR) on nasopharyngeal swab specimens. Results Fifty index cases and 214 contacts (64 household) were enrolled. Sixty-five contacts were RT-PCR positive during ≥1 visit. Vaccination did not influence viral load. Gamma variants were most prevalent; Delta variants emerged increasingly during implementation. The overall sensitivity of evaluated tests ranged from 33% to 76%. Performance was higher among symptomatic cases and those with cycle threshold (Ct) values <34 and lower among oligosymptomatic or asymptomatic cases. Assuming a 24-hour time to results for RT-PCR, the cumulative sensitivity of an anterior nares swab rapid antigen test was >70% and almost 90% after 4 days. Conclusions The near-immediate time to results for antigen tests significantly offsets lower analytical sensitivity in settings where RT-PCR results are delayed or unavailable. [ABSTRACT FROM AUTHOR]
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- 2022
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7. Genomic Variability of Hepatitis B Virus Circulating in Brazilian Western Amazon.
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Roca, Tárcio Peixoto, Villar, Livia Melo, Nogueira Lima, Felipe Souza, Vasconcelos, Mariana Pinheiro Alves, Borzacov, Lourdes Maria Pinheiro, Silva, Eugênia de Castro e, Lago, Bárbara Vieira do, Silva, Mayara Torquato Lima da, Botelho Souza, Luan Felipo, Salcedo, Juan Miguel Villalobos, Santos, Alcione de Oliveira dos, and Vieira, Deusilene Souza
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HEPATITIS B virus ,DRUG resistance ,DISEASE progression - Abstract
The emergence of clinically relevant mutations in the hepatitis B virus (HBV) genome has been a matter of great debate because of the possibility of escape from the host's immune system, the potential to cause more severe progression of liver diseases and the emergence of treatment-resistant variants. Here we characterized the circulating variants of HBV in Rondônia State, in the north of Brazil. Serum samples of 62 chronic HBV carriers were subjected to PCR assays and clinical data were collected. Mutations and genotypes were characterized through direct sequencing. The findings show the presence of subgenotypes A1 (54.83%, 34/62), D3 (16.13%, 10/62), F2 (16.13%, 10/62), A2 (4.84%, 3/62), D2 (3.23%, 2/62), D1 (1.61%, 1/62), D4 (1.61%, 1/62) and F4 (1.61%, 1/62). Deletions in the pre-S2 region were found in 13.79% (8/58) of the samples, mutations in the S gene in 59.68% (37/62) and RT mutations in 48.39% (30/62). We found a variable genotypic distribution in different locations and important mutations related to immune escape and drug resistance in Western Amazonia, which contributed to genetic surveillance and provided important information to help control the disease. [ABSTRACT FROM AUTHOR]
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- 2022
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8. SARS-CoV-2 genomic surveillance in Rondônia, Brazilian Western Amazon.
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Botelho-Souza, Luan Felipo, Nogueira-Lima, Felipe Souza, Roca, Tárcio Peixoto, Naveca, Felipe Gomes, de Oliveria dos Santos, Alcione, Maia, Adriana Cristina Salvador, da Silva, Cicileia Correia, de Melo Mendonça, Aline Linhares Ferreira, Lugtenburg, Celina Aparecida Bertoni, Azzi, Camila Flávia Gomes, Fontes, Juliana Loca Furtado, Cavalcante, Suelen, de Cássia Pontello Rampazzo, Rita, Santos, Caio Henrique Nemeth, Di Sabatino Guimarães, Alice Paula, Máximo, Fernando Rodrigues, Villalobos-Salcedo, Juan Miguel, and Vieira, Deusilene Souza
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COVID-19 pandemic ,DISEASE incidence ,DEATH rate ,DNA replication - Abstract
SARS-CoV-2 has spread rapidly around the world, with Brazil currently considered an epicenter of the pandemic. The Northern region has the second highest incidence coefficient, as well as the third highest mortality rate in the country. This study aimed to investigate information about the evolutionary history of epidemic spread and genetic aspects of strains isolated on the Western Amazon, in the State of Rondônia, Brazil. It was possible to detect a total of 22 mutations. Some of these alterations may possibly be related to effects on transmissibility, the fidelity of RNA replication, the ability of cancer patients to respond to infection, beyond a mutation that emerged after the introduction of SARS-CoV-2 in Rondônia. At least two events of introduction were detected, corresponding to the B.1 and B.1.1 European lineages. An introduction was observed possibly through Argentina, where strains originated that circulated in the Minas Gerais and Ceará Brazilian states, prior to Rondônia (B.1.), as well as through the Minas Gerais state and the Federal District, which gave rise to strains that spread to Rondônia, from the capital to more rural parts of the state (B.1.1.). The findings show the need to monitor the genetic epidemiology of COVID-19, in order to surveil the virus's evolution, dispersion and diversity. [ABSTRACT FROM AUTHOR]
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- 2021
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9. Serosurvey of Eastern, Western, and Venezuelan Equine Encephalitis Viruses in Wild Boars (Sus scrofa), Hunting Dogs, and Hunters of Brazil.
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Bach Kmetiuk, Louise, dio de Souza Hunold Lara, Maria do Carmo CustÓ, Cassaro Villalobos, Eliana Monteforte, de Barros Filho, Ivan Roque, Marinelli Martins, Camila, van Wilpe Bach, Renato, Pistori Machado, Fernanda, Silva Pereira, Monicque, Cavalcante Lipinski, Leandro, Pires dos Santos, Andrea, and Welker Biondo, Alexander
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VENEZUELAN equine encephalomyelitis ,ENCEPHALITIS viruses ,HUNTING dogs ,WILD boar ,ZIKA Virus Epidemic, 2015-2016 ,NEUTRALIZATION tests - Abstract
A total of 102 free-range wild boars, 170 hunting dogs, and 49 hunters from 3 Brazilian regions were sampled and tested for antibodies to eastern equine encephalitis virus (EEEV), western equine encephalitis virus, and Venezuelan equine encephalitis virus. Three of the 102 (2.9%) wild boars were positive for antibodies against EEEV by microplate serum neutralization test. Based on our data, free-range wild boars from central-western Brazil may be exposed to EEEV, and further studies are needed to evaluate the potential of incorporating serosurveys in routine arbovirus activity surveillance specifically to identify arbovirus activity foci and to help establish thresholds for epidemic transmission. [ABSTRACT FROM AUTHOR]
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- 2020
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10. Prevalence of traumatic orofacial and dental injury in unidentified bodies-Data from a forensic medicine institute in Brazil.
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Villalobos, Maria Isabel de Oliveira e Britto, Santos, Alyssa Sales, Horta, Martinho Campolina Rebello, Miranda, Geraldo Elias, Bastos, Juliana Vilela, Côrtes, Maria Ilma de Souza Gruppioni, and Dos Santos, Alyssa Sales
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OROFACIAL pain , *TEETH injuries , *FACIAL injuries , *DISEASE prevalence , *MEDICAL care costs , *VIOLENCE , *RETROSPECTIVE studies , *RESEARCH funding , *FORENSIC medicine - Abstract
Background/aim: Orofacial trauma and traumatic dental injuries (TDI) are serious public health problems due to their high prevalence, severe morbidity, high costs of treatment, and long-term sequelae. However, the extent of the problem may be underestimated since trauma analysis, from a forensic odontology perspective, is not widely represented in the scientific literature. The aim of this study was to investigate the occurrence of traumatic orofacial injuries (TOI) and TDI in unidentified bodies and their association with the cause of death.Materials and Methods: A retrospective analysis was conducted of dental and autopsy reports of unidentified bodies admitted to the Institute of Forensic Medicine of Belo Horizonte (IFM-BH), Brazil, between 2015 and 2016. The final sample was made up of 536 bodies. Demographic data, the location where the body was found, cause of death, and the presence and type of orofacial trauma were collected.Results: The mean of the estimated age of the bodies was 38 years and the median was 35 years. Most of the bodies were from males (87.5%) and were found downtown in the city of Belo Horizonte (60.4%). Violence was the most common cause of death (64%), generally by gunshot (48.7%). Bodies with an estimated age ≤35 years were eight times more likely to have died from violent causes. TOI was registered in 50.9% of the reports. TDI was observed in 10.8% of the bodies. Victims of violent death were seven times more likely to present TOI. Such association was not observed when the presence of TDI was considered.Conclusions: There is a positive association between TOI and violent death in unidentified bodies. [ABSTRACT FROM AUTHOR]- Published
- 2020
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11. A dark scenario for Cerrado plant species: Effects of future climate, land use and protected areas ineffectiveness.
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Velazco, Santiago José Elías, Villalobos, Fabricio, Galvão, Franklin, De Marco Júnior, Paulo, and Serra‐Diaz, Josep
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PLANT species , *PROTECTED areas , *LAND use , *EFFECT of human beings on climate change , *HABITAT conservation - Abstract
Aim: The anthropogenic climate change and land use change are considered two of the main factors that are altering biodiversity at the global scale. An evaluation that combined both factors can be relevant to detect which species could be the most vulnerable and reveal the regions of highest stability or susceptibility to biodiversity. We aimed to: (a) assess the effect of climate change and land use on the distribution of Cerrado plant species for different countries where they occur, (b) evaluate the effectiveness of the current network of protected areas (PAs) to safeguards species under different greenhouse–gas (GHG) emissions and land use scenarios, and (c) estimate the vulnerability of species based on protection effectiveness and habitat loss. Location: Bolivia, Brazil and Paraguay. Methods: We modelled the distribution of 1,553 plant species of Cerrado and evaluated species range loss caused by present and future land use and two GHG for 2050 and 2080. We assessed species vulnerability combining the representativeness of species within conservation units with the loss of species' ranges outside PAs. Results: We found that climate change and land use will cause great damage to Cerrado flora by 2050 and 2080, even under optimistic conditions. The greatest impacts of land use will occur in the regions where the greatest richness will be harboured. The conservation of the species will be seriously affected since the PA network is not as effective in safeguarding them under current or future conditions. Main conclusions: The low level of protection together with the losses caused by the advance of agricultural lands will lead most species being highly vulnerable. Due to the distinct impacts of climate and land use over the three countries, conservation strategies should be implemented at transboundary and national levels. [ABSTRACT FROM AUTHOR]
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- 2019
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12. Transboundary conservation opportunities for Cerrado's plant species.
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Velazco, Santiago José Elías, Villalobos, Fabricio, Galvão, Franklin, and De Marco Júnior, Paulo
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CERRADOS , *PLANT species , *SAVANNAS , *WILDLIFE conservation , *ENDANGERED species - Abstract
Cerrado is considered one of the world's most threatened and floristically diverse tropical savannas. Distribution of the Cerrado flora comprises three countries: Bolivia, Brazil, and Paraguay; consequently, opportunities to conserve it require a transboundary effort. We aimed to (i) explore the relationship between a representative portion of Cerrado flora (8611 species), natural cover loss, and three country boundaries; and (ii) identify priority areas to expand protected areas at national and transboundary levels considering the different species conservation status, countries' governance, and natural cover loss. We modeled the distribution of Cerrado species for the three countries and overlapped species ranges with country boundaries to calculate species ranges shared between countries and the degree of endemicity. We identified national and transboundary priority regions to expand protected areas. We found that the areas with the highest plant richness are distributed in the central part of the Cerrado and Campos Rupestres Mountain Savanna ecoregions in Brazil (>8500 for the whole country). Bolivia ranked second in species richness (>4300), followed by Paraguay (>3700). The most anthropized areas in Brazil overlapped with regions predicted to foster the highest biodiversity. Conversely, such patterns were opposite in Bolivia and Paraguay, which harbored regions with high opportunities for Cerrado flora conservation. Transboundary prioritization suggested slightly higher species protection, including threatened and endemic species. Restoring some regions primarily in Brazil will be necessary to protect 30 % or 50 % of the study area. Together, the three countries can support more comprehensive conservation actions for the great diversity of the Cerrado flora. • Cerrado is one of the most threatened and floristically diverse tropical savannas. • Many plant species are distributed across Bolivia, Brazil, and Paraguay. • Most anthropized areas in Brazil are in regions with the highest plant richness. • Transboundary prioritization performed slightly better than national prioritization. • Three countries can support more comprehensive conservation actions for Cerrado. [ABSTRACT FROM AUTHOR]
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- 2023
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13. Characterization of the Genotypic Profile of Hepatitis Delta Virus: Isolation of HDV Genotype-1 in the Western Amazon Region of Brazil.
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Botelho-Souza, Luan Felipo, Souza Vieira, Deusilene, de Oliveira dos Santos, alcione, Cunha Pereira, andré Vinycius, and Villalobos-Salcedo, Juan Miguel
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HEPATITIS D virus ,VIRAL genomes ,HEPATITIS B virus ,EPIDEMICS ,DISEASE prevalence - Abstract
The hepatitis delta virus (HDV) is a hepatotropic subvirus that is dependent on the hepatitis B virus (HBV) and supplies the viral envelope containing the surface antigen of hepatitis B. Viral genetic diversity is related to the geographical origin of the isolates, and there are at least eight genotypes that are referred to as HDV-1 through HDV-8. HDV-3 is responsible for epidemics of severe and fulminant hepatitis, which are common in northeastern South America. HDV-3 is prevalent in the Brazilian Amazon and is associated with the increased aggressiveness of HDV infections. Although isolated, the characteristics of the clinical presentation of HDV-1 in the Amazon region have not yet been clearly reported. Objective: This study aims to assess the genotypic and clinical characteristics of individuals with the HDV-1 genotype in the western Amazon region. Methods: The HDV was genotyped by nested PCR-RFLP and sequencing from serum samples of 56 patients with HBV/HDV infection. The genotypes were correlated with the clinical characteristics presented by patients with HBV/HDV infection. Results: A prevalence of 92.3% for the HDV-3 genotype (n = 48) and 7.6% (n = 4) for the HDV-1 genotype was observed. Conclusion: To date, this is the most extensive clinical study of HDV-1 genotype infections in the nonindigenous population of Western Amazonia. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]
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- 2015
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14. Development of cost-effective real-time PCR test: to detect a wide range of HBV DNA concentrations in the western amazon region of Brazil.
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de Oliveira dos Santos, Alcione, de Souza, Luan Felipo Botelho, Borzacov, Lourdes Maria, Villalobos-Salcedo, Juan Miguel, and Vieira, Deusilene Souza
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HEPATITIS B virus ,BLOOD transfusion ,DNA ,POLYMERASE chain reaction - Abstract
Background Currently there is a significant risk of infection with hepatitis B virus (HBV) during blood transfusion in high epidemic area. This is due to the pre-seroconversion window period, immunovariant viral strains and the presence of occult HBV infection (OBI). The aim of this study was to develop an in-house real-time PCR-based method, which was both ultrasensitive and efficient offering an alternative method for nucleic acid testing (NAT). Methods A precore fragment with 109 bp was cloned and serial diluted to standard curve construction. The calibration of the HBV - DNA values was performed against OptiQuant® HBV-DNA Quantification Panel, Acrometrix Europe B.V.). Results From our in-house plasmid we prepared serial dilutions ranging from 2 × 10
3 - 2 × 109 copies/ml. The threshold was adjusted automatically during analysis and the data collected were analyzed by linear regression (r2 = 0.99). The limit of detection for the assay with pHBVRO standards was 2000/ml in a total reaction volume of 30 μl. We found a strong correlation between the two methods (r2 = 0.9965 and p < 0.0001). The regression line give us the following equation: Log 10 (IU/mL) = 0.9038Log 10 (copies/mL) - 1.0643, suggesting that 1 IU/mL = 15 copies/mL. Conclusions Therefore, we can affirm that the qHBVRO PCR can detect HBV DNA in individuals with hepatitis B at any stage of the disease showing high capacity for NAT screening in hepatitis b donors. This results of sensitivity could provide an advance for automation in blood banks and increasing safety of patients who receive blood transfusions. [ABSTRACT FROM AUTHOR]- Published
- 2014
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15. West Nile virus surveillance, Brazil, 2008–2010.
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Ometto, Tatiana, Durigon, Edison Luiz, de Araujo, Jansen, Aprelon, Rosalie, de Aguiar, Daniel Moura, Cavalcante, Guacyara Tenorio, Melo, Rosane Marini, Levi, José Eduardo, Júnior, Severino Mendes de Azevedo, Petry, Maria Virgínia, Neto, Isaac Simão, Serafini, Patrícia, Villalobos, Eliana, Cunha, Elenice Maria Sequetin, Lara, Maria do Carmo Custódio S. H., Nava, Alessandra Ferreira Dales, Nardi, Marcello Schiavo, Hurtado, Renata, Rodrigues, Roberta, and Sherer, Angelo Luís
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WEST Nile virus ,VIRAL transmission ,PUBLIC health ,SEROLOGY ,ENZYME-linked immunosorbent assay - Abstract
Background West Nile virus (WNV) is an emergent pathogen that is widely distributed in North and Central America. The recent introduction in South America has focused attention on the spread of WNV across Southern American countries. The transmission network involves mosquitoes, birds, horses and humans. Methods The serological evaluation of sera from 678 equids and 478 birds was performed using a WNV-specific blocking ELISA, and only the positive results were confirmed by plaque reduction neutralisation tests (PRNTs). Molecular analysis was performed on sera from 992 healthy equids and on 63 macerates of brains from equids that died of encephalitis and had previously tested negative for other pathogens. We also tested swabs from 928 birds. The samples analysed were collected in different biomes of Brazil. Results We identified WNV antibodies by ELISA in thirteen equids and five birds, and PRNT90 confirmed WNV positivity in four equid samples collected in 2009 in an area between the Amazon and the Pantanal. None of the ELISA positive bird samples were confirmed by PRNT90, and all samples tested by RT-PCR were negative. Conclusion WNV circulation is confirmed by this large scale survey even in the absence of detection of clinical cases. [ABSTRACT FROM AUTHOR]
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- 2013
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16. Assessing the impact of cigarette package health warning labels: a cross-country comparison in Brazil, Uruguay and Mexico.
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Thrasher, James F., Villalobos, Victor, Szklo, André, Fong, Geoffrey T., Pérez, Cristina, Sebrié, Ernesto, Sansone, Natalie, Figueiredo, Valeska, Boado, Marcelo, Arillo-Santillán, Edna, and Bianco, Eduardo
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SMOKING , *HEALTH , *CIGARETTE package labels , *WARNING label policy , *EDUCATIONAL attainment , *COGNITIVE ability - Abstract
Objective. To assess the impact of different health warning labels (HWL). Material and Methods. Data from the International Tobacco Control Survey (ITC Survey) were analyzed from adult smokers in Brazil, Uruguay and Mexico, each of which used a different HWL strategy (pictures of human suffering and diseased organs; abstract pictorial representations of risk; and text-only messages, respectively). Main outcomes were HWL salience and cognitive impact. Results. HWLs in Uruguay (which was the only country with a HWL on the front of the package) had higher salience than either Brazilian or Mexican packs. People at higher levels of educational attainment in Mexico were more likely to read the text-only HWLs whereas education was unassociated with salience in Brazil or Uruguay. Brazilian HWLs had greater cognitive impacts than HWLs in either Uruguay or Mexico. HWLs in Uruguay generated lower cognitive impacts than the text-only HWLs in Mexico. In Brazil, cognitive impacts were strongest among smokers with low educational attainment. Conclusions. This study suggests that HWLs have the most impact when they are prominent (i.e., front and back of the package) and include emotionally engaging imagery that illustrates negative bodily impacts or human suffering due to smoking. [ABSTRACT FROM AUTHOR]
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- 2010
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17. Size-dependent mortality in a Neotropical savanna tree: the role of height-related adjustments in hydraulic architecture and carbon allocation.
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YONG-JIANG ZHANG, MEINZER, FREDERICK C., GUANG-YOU HAO, SCHOLZ, FABIAN G., BUCCI, SANDRA J., TAKAHASHI, FREDERICO S. C., VILLALOBOS-VEGA, RANDOL, GIRALDO, JUAN P., KUN-FANG CAO, HOFFMANN, WILLIAM A., and GOLDSTEIN, GUILLERMO
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SAVANNA plants ,PLANT species ,PLANT size ,CERRADOS - Abstract
Size-related changes in hydraulic architecture, carbon allocation and gas exchange of Sclerolobium paniculatum (Leguminosae), a dominant tree species in Neotropical savannas of central Brazil (Cerrado), were investigated to assess their potential role in the dieback of tall individuals. Trees greater than ∼6-m-tall exhibited more branch damage, larger numbers of dead individuals, higher wood density, greater leaf mass per area, lower leaf area to sapwood area ratio (LA/SA), lower stomatal conductance and lower net CO
2 assimilation than small trees. Stem-specific hydraulic conductivity decreased, while leaf-specific hydraulic conductivity remained nearly constant, with increasing tree size because of lower LA/SA in larger trees. Leaves were substantially more vulnerable to embolism than stems. Large trees had lower maximum leaf hydraulic conductance ( Kleaf ) than small trees and all tree sizes exhibited lower Kleaf at midday than at dawn. These size-related adjustments in hydraulic architecture and carbon allocation apparently incurred a large physiological cost: large trees received a lower return in carbon gain from their investment in stem and leaf biomass compared with small trees. Additionally, large trees may experience more severe water deficits in dry years due to lower capacity for buffering the effects of hydraulic path-length and soil water deficits. [ABSTRACT FROM AUTHOR]- Published
- 2009
- Full Text
- View/download PDF
18. Biophysical and life-history determinants of hydraulic lift in Neotropical savanna trees.
- Author
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Scholz, F. G., Bucci, S. J., Goldstein, G., Moreira, M. Z., Meinzer, F. C., Domec, J.-C., Villalobos-Vega, R., Franco, A. C., and Miralles-Wilhelm, F.
- Subjects
BOTANY ,PLANTS ,HYDRAULICS ,PLANT species ,TREES ,SAP (Plant) ,COAST live oak ,PLANT transpiration ,CERRADO plants ,CERRADOS ,CARBON ,SAVANNAS - Abstract
1. Ecological and physiological characteristics of vascular plants may facilitate or constrain hydraulic lift. Studies of hydraulic lift typically include only one or few species, but in species-rich ecosystems a larger number of representative species needs to be studied. 2. Measurements of sap flow in tap roots, lateral roots and stems, as well as stable isotope labelling techniques were used to determine the occurrence and relative magnitude of hydraulic lift in several individuals of nine co-occurring Brazilian savanna (Cerrado) tree species differing in life-history traits, and to assess physical and biological determinants of this process at the tree and ecosystem level. 3. The occurrence of reverse sap flow observed in deciduous and brevideciduous species during the dry season was consistent with hydraulic lift. The evergreen species did not exhibit reverse flow. Consistent with their ability to carry out hydraulic lift, the brevideciduous and deciduous species had both shallow and tap roots (dimorphic root systems), whereas the evergreen species had mostly deep roots (monomorphic root systems). 4. In the deciduous and brevideciduous species, the contribution of tap roots to transpiration increased substantially as the dry season progressed. Seasonal changes in the contribution of tap roots to transpiration were not observed in the evergreen species. 5. There was an inverse relationship between rates of reverse sap flow and seasonal loss of hydraulic conductivity in lateral roots, suggesting that hydraulic lift in Cerrado woody plants may help maintain the functionality of the lateral roots in exploring dry and nutrient rich superficial soil layers without directly enhancing the amount of water uptake. 6. Reverse sap flow in lateral roots of the deciduous and brevideciduous species increased asymptotically as the driving force for water movement from roots to the soil increased. This nonlinear relationship implies that additional sinks for water such as nocturnal transpiration and refilling of internal water storage tissues may compete for internal water resources during the dry season. 7. There appears to be a trade-off between greater year-round access to nutrients in the upper soil layers (deciduous and brevideciduous species) and a greater access to deep and more reliable water sources during the dry season (evergreen species), which has implications for whole-ecosystem water, carbon and nutrient balance in Neotropical savannas. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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19. Molecular characterization of Brucella ovis in Argentina.
- Author
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Alvarez, Lucía P., Ruiz-Villalobos, Nazaret, Suárez-Esquivel, Marcela, Thomson, Nicholas R., Marcellino, Romanela, Víquez-Ruiz, Eunice, Robles, Carlos A., and Guzmán-Verri, Caterina
- Subjects
- *
BRUCELLA , *BRUCELLA melitensis , *TANDEM repeats , *BRUCELLOSIS , *NUCLEOTIDE sequencing - Abstract
• Analysis of MLVA-16 revealed a high diversity among B. ovis isolates. • Argentinean isolates are related to B. ovis from New Zealand and Australia. • Isolates from Argentina, Uruguay and Brazil were grouped into two clades. • This work constitutes the largest study of B. ovis molecular genotyping until now. Brucellosis in rams is caused by Brucella ovis or Brucella melitensis and it is considered one of the most important infectious diseases of males in sheep-raising countries. Molecular characterization of Brucella spp. achieved by multi-locus variable number of tandem repeats analysis (MLVA) is a powerful tool to genotype Brucella spp. However, data regarding B. ovis genotyping is scarce. Thus, the aim of this study was to characterize the molecular diversity of B. ovis field-strains in Argentina. A total of 115 isolates of B. ovis from Argentina and Uruguay were genotyped using MLVA-16 and analyzed altogether with 14 publicly available B. ovis genotypes from Brazil. The Discriminatory Power (D) was 0.996 for MLVA-16 and 0.0998 for MLVA-8 and MLVA-11. Analysis of MLVA-16 revealed 100 different genotypes, all of them novel, including 90 unique ones. There was no correlation between geographical distribution and genotype and results showed a higher diversity within provinces than between provinces. Clustering analysis of the strains from Argentina, Uruguay and Brazil revealed that the 129 isolates were grouped into two clades. Whole Genome Sequencing analysis of the 19 B. ovis genomes available in public databases, and including some of the Argentinian strains used in this study, revealed clustering of the Argentinian isolates and closer relationship with B. ovis from New Zealand and Australia. This work adds new data to the poorly understood distribution map of genotypes regionally and worldwide for B. ovis and it constitutes the largest study of B. ovis molecular genotyping until now. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
20. In-vivo sensitivity of Plasmodium vivaxisolates from Rondônia (western Amazon region, Brazil) to regimens including chloroquine and primaquine.
- Author
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Villalobos-Salcedo, J. M., Tada, M. S., Kimura, E., Menezes, M. J., and Pereira-Da-Silva, L. H.
- Subjects
- *
MALARIA treatment , *PLASMODIUM vivax - Abstract
Seventy-nine adults with Plasmodium vivax malaria, from the Porto Velho area of Rondoˆnia (western Amazon region, Brazil), gave informed consent to participate in a blind, clinical study of two regimens of treatment with chloroquine (CQ) and primaquine. The effectiveness of the 'classical' regimen (CQ for 3 days, followed by primaquine for 14 days) was compared with that of a 'short' regimen in which the two drugs were given simultaneously for 5 days. There were no cases of recrudescence indicative of CQ resistance (i.e. within 30 days of the first treatment dose) among the 73 patients who each completed a full, supervised course of treatment. However, 10 cases of apparent relapse were observed (all > 60 days after first treatment dose), representing 6.5% (2/31) of the patients who completed 60 days of follow-up after the classical treatment and 26.7% (8/30) of the short-regimen patients who completed the same period of follow-up. PCR-based comparison of parasitic DNA collected pre- and post-treatment was successful for eight of the 10 cases of apparent relapse and indicated that two such cases, both given the short regimen of treatment, were, in fact, probable cases of re-infection rather than of relapse. The results indicate that the classical schedule of treatment with chloroquine and primaquine was more effective at preventing relapses than the short regimen. However, since prolonged treatment with primaquine often produces side-effects that are severe enough to reduce compliance, the short schedule could be a useful alternative for malaria control in endemic areas of the Amazon region. [ABSTRACT FROM AUTHOR]
- Published
- 2000
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21. Depth of water uptake in woody plants relates to groundwater level and vegetation structure along a topographic gradient in a neotropical savanna
- Author
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Rossatto, Davi Rodrigo, de Carvalho Ramos Silva, Lucas, Villalobos-Vega, Randoll, Sternberg, Leonel da Silveira Lobo, and Franco, Augusto César
- Subjects
- *
PLANTS , *WOODY plants , *GROUNDWATER , *SAVANNAS , *PLANT-water relationships , *HYDROGEN isotopes , *OXYGEN isotopes , *PLANT roots - Abstract
Abstract: Vegetation structure of the savannas is variable across the landscape, ranging from open grassland to savanna woodland within topographic gradients of a few hundred meters in length. Here we investigated whether patterns of soil water extraction by the woody layer and vegetation structure changed in response to groundwater depth. We determined depth of plant water uptake, groundwater level and vegetation structure on five different locations along a topographic gradient in the highlands of Central Brazil. The elevation gradient of about 110m covered all vegetation physiognomies generally associated with topographic gradients in savannas of Central Brazil. To estimate the depth of plant water uptake in the different slope positions we relied on comparisons of hydrogen and oxygen isotope ratios of plant stem water, water from different soil depths, from groundwater and from rainfall. We subsequently used a stable isotope mixing model to estimate vertical partitioning of soil water by woody plants along the elevation gradient. We were able to show that groundwater level affected plant water uptake patterns and soil water partitioning among savanna woody species. Vegetation at higher elevation extracted water from deeper unsaturated soils and had greater variability in water uptake strategies, which was coupled to a denser and more complex woody layer. Plants on these soils used stored water from both shallow (<0.6m) and deep (0.6–2.00m) soil layers. At lower elevation sites, however, the presence of a water table near the soil surface restricted water uptake to the shallower wet season unsaturated zone of the soil profile. The sparser woody vegetation is probably composed of species that only rely in superficial water uptake, or are plastic in relation to root characteristics. [Copyright &y& Elsevier]
- Published
- 2012
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22. Development of a reverse transcription quantitative real-time PCR-based system for rapid detection and quantitation of hepatitis delta virus in the western Amazon region of Brazil.
- Author
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Botelho-Souza, Luan Felipo, dos Santos, Alcione de Oliveira, Borzacov, Lourdes Maria, Honda, Eduardo Resende, Villalobos-Salcedo, Juan Miguel, and Vieira, Deusilene Souza
- Subjects
- *
REVERSE transcriptase polymerase chain reaction , *HEPATITIS D virus , *GENE amplification , *CALIBRATION , *CELL surface antigens , *FLUORESCENCE resonance energy transfer - Abstract
Highlights: [•] We developed of a system for rapid detection and quantitation of HDV. [•] We designed primers and FRET probes were capable of binding to 8 genotypes. [•] We produce two calibration standards. [•] The amplification efficiency of HDV RT-qPCR was 99.8%. [•] Is the first HDV RT-qPCR assay developed in the western Amazon region in Brazil. [Copyright &y& Elsevier]
- Published
- 2014
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23. Regional deforestation drives the impact of forest cover and matrix quality on primate species richness.
- Author
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Galán-Acedo, Carmen, Spaan, Denise, Bicca-Marques, Júlio César, de Azevedo, Renata Bocorny, Villalobos, Fabricio, and Rosete-Vergés, Fernando
- Subjects
- *
DEFORESTATION , *SPECIES diversity , *FOREST conservation , *FOREST restoration , *FOREST density - Abstract
Land-use change transforms natural ecosystems, threatening species persistence worldwide. There is increasing evidence that forest loss negatively affects forest-dependent species and matrix quality can favor species maintenance, whereas forest fragmentation has mainly null or positive effects on species. However, the effects of these landscape attributes may depend on the level of regional deforestation. Here, we assess the effects of forest cover, matrix quality, and forest fragmentation (forest patch density) on primate species richness in 92 landscapes in Brazil. We grouped landscapes by their regional deforestation level into low, intermediate, high, and severe deforestation. The effects of landscape attributes varied depending on the level of regional deforestation. Forest loss decreased the proportion of primate species in the four regional deforestation levels, but this association was more important in the low, intermediate and high regional deforestation levels. Matrix quality was positively related to the proportion of primate species in three regional deforestation levels and this association was more important in the high regional deforestation level. Yet, matrix quality decreased the proportion of primate species in the severe regional deforestation level. Forest fragmentation had no clear effects across all deforestation levels. Therefore, different conservation strategies should be prioritized under distinct scenarios. Preventing forest loss is needed in all regions. Increasing matrix quality has positive effects on species richness, especially in highly deforested regions (30–15% remaining forest cover). Finally, as fragmentation had no clear effects on the proportion of primate species, landscape composition should be prioritized in conservation planning over landscape configuration. • Landscape effects on primate richness are influenced by regional deforestation. • Preventing forest loss is important in the four regional levels. • Improving matrix quality with arboreal elements is key in highly deforested regions. • Forest restoration and preservation is paramount in severely deforested regions. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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24. Public policy on the prevention of subsequent adolescent pregnancy: what type of policy prevails?
- Author
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Estrada F, Romero-Pérez I, Campero L, Hubert C, and Villalobos A
- Subjects
- Adolescent, Brazil, Female, Health Policy, Humans, Mexico, Pregnancy, Public Policy, Pregnancy in Adolescence prevention & control
- Abstract
This study aims to conduct a search of public-policy instruments seeking explicit references to subsequent adolescent pregnancy, as well as to discern what kinds of actions have been proposed as part of the international and national agendas to facilitate subsequent adolescent pregnancy prevention and care. During June 2021, we used an integrative review to search and to analyze national and international public policy instruments along with other documents related to subsequent adolescent pregnancy. We observed, for each, the presence of statements on subsequent adolescent pregnancy. The research team was then divided into triads to discuss and to classify each reference under one of the following categories: (a) a symbolic statement, that is, an intention not implying a specific action but rather presenting a vision for the future; (b) a substantive-material statement concerning an action intended to solve a problem; and (c) a procedural-material statement indicating specific actions, processes, budgets, and actors. We analyzed a total of 135 public-policy documents: 102 in Mexico and 33 internationally. Only four national and six international documents contained either symbolic or substantive-material references to the subject of interest and only one specified a procedural-material statement. The prevention and care of subsequent adolescent pregnancy are addressed only secondarily on the public agendas. Only a minimal number of actions comprise specific and standardized measures to prevent subsequent adolescent pregnancy according to the different actors involved. Designing a greater number of procedural-material policies will help to reduce morbidity and mortality in the mother-child binomial and promote a comprehensive development of this population.
- Published
- 2022
- Full Text
- View/download PDF
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