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1.
Arq Bras Cir Dig ; 33(1): e1496, 2020 Jul 08.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-32667526

RESUMEN

BACKGROUND: Incidental gallbladder cancer is defined as a cancer discovered by histological examination after cholecystectomy. It is a potentially curable disease. However, some questions related to their management remain controversial and a defined strategy is associated with better prognosis. AIM: To develop the first evidence-based consensus for management of patients with incidental gallbladder cancer in Brazil. METHODS: Sixteen questions were selected, and 36 Brazilian and International members were included to the answer them. The statements were based on current evident literature. The final report was sent to the members of the panel for agreement assessment. RESULTS: Intraoperative evaluation of the specimen, use of retrieval bags and routine histopathology is recommended. Complete preoperative evaluation is necessary and the reoperation should be performed once final staging is available. Evaluation of the cystic duct margin and routine 16b1 lymph node biopsy is recommended. Chemotherapy should be considered and chemoradiation therapy if microscopically positive surgical margins. Port site should be resected exceptionally. Staging laparoscopy before reoperation is recommended, but minimally invasive radical approach only in specialized minimally invasive hepatopancreatobiliary centers. The extent of liver resection is acceptable if R0 resection is achieved. Standard lymph node dissection is required for T2 tumors and above, but common bile duct resection is not recommended routinely. CONCLUSIONS: It was possible to prepare safe recommendations as guidance for incidental gallbladder carcinoma, addressing the most frequent topics of everyday work of digestive and general surgeons.


Asunto(s)
Neoplasias de la Vesícula Biliar , Brasil , Carcinoma , Consenso , Femenino , Humanos , Hallazgos Incidentales , Escisión del Ganglio Linfático , Estadificación de Neoplasias , Tomografía Computarizada por Tomografía de Emisión de Positrones , Estudios Retrospectivos
2.
Glob Chang Biol ; 26(5): 3122-3133, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32053250

RESUMEN

Drought-related tree mortality is now a widespread phenomenon predicted to increase in magnitude with climate change. However, the patterns of which species and trees are most vulnerable to drought, and the underlying mechanisms have remained elusive, in part due to the lack of relevant data and difficulty of predicting the location of catastrophic drought years in advance. We used long-term demographic records and extensive databases of functional traits and distribution patterns to understand the responses of 20-53 species to an extreme drought in a seasonally dry tropical forest in Costa Rica, which occurred during the 2015 El Niño Southern Oscillation event. Overall, species-specific mortality rates during the drought ranged from 0% to 34%, and varied little as a function of tree size. By contrast, hydraulic safety margins correlated well with probability of mortality among species, while morphological or leaf economics spectrum traits did not. This firmly suggests hydraulic traits as targets for future research.


Asunto(s)
Sequías , El Niño Oscilación del Sur , Costa Rica , Bosques , Hojas de la Planta , Clima Tropical
3.
ABCD (São Paulo, Impr.) ; 33(1): e1496, 2020.
Artículo en Inglés | LILACS | ID: biblio-1130518

RESUMEN

ABSTRACT Background: Incidental gallbladder cancer is defined as a cancer discovered by histological examination after cholecystectomy. It is a potentially curable disease. However, some questions related to their management remain controversial and a defined strategy is associated with better prognosis. Aim: To develop the first evidence-based consensus for management of patients with incidental gallbladder cancer in Brazil. Methods: Sixteen questions were selected, and 36 Brazilian and International members were included to the answer them. The statements were based on current evident literature. The final report was sent to the members of the panel for agreement assessment. Results: Intraoperative evaluation of the specimen, use of retrieval bags and routine histopathology is recommended. Complete preoperative evaluation is necessary and the reoperation should be performed once final staging is available. Evaluation of the cystic duct margin and routine 16b1 lymph node biopsy is recommended. Chemotherapy should be considered and chemoradiation therapy if microscopically positive surgical margins. Port site should be resected exceptionally. Staging laparoscopy before reoperation is recommended, but minimally invasive radical approach only in specialized minimally invasive hepatopancreatobiliary centers. The extent of liver resection is acceptable if R0 resection is achieved. Standard lymph node dissection is required for T2 tumors and above, but common bile duct resection is not recommended routinely. Conclusions: It was possible to prepare safe recommendations as guidance for incidental gallbladder carcinoma, addressing the most frequent topics of everyday work of digestive and general surgeons.


RESUMO Racional: Carcinoma incidental da vesícula biliar é definido como uma neoplasia descoberta por exame histológico após colecistectomia videolaparoscópica. É potencialmente uma doença curável. Entretanto algumas questões relacionadas ao seu manuseio permanecem controversas e uma estratégia definida está associada com melhor prognóstico. Objetivo: Desenvolver o primeiro consenso baseado em evidências para o manuseio de pacientes com carcinoma incidental da vesícula biliar no Brasil. Métodos: Dezesseis questões foram selecionadas e para responder as questões e 36 membros das sociedades brasileiras e internacionais foram incluídos. As recomendações foram baseadas em evidências da literatura atual. Um relatório final foi enviado para os membros do painel para avaliação de concordância. Resultados: Avaliação intraoperatória da peça cirúrgica, uso de bolsas para retirar a peça cirúrgica e exame histopatológico de rotina, foram recomendados. Avaliação pré-operatória completa é necessária e deve ser realizada assim que o estadiamento final esteja disponível. Avaliação da margem do ducto cístico e biópsia de rotina do linfonodo 16b1 são recomendadas. Quimioterapia deve ser considerada e quimioradioterapia indicada se a margem cirúrgica microscópica seja positiva. Os portais devem ser ressecados excepcionalmente. O estadiamento laparoscópico antes da operação é recomendado, mas o tratamento radical por abordagem minimamente invasiva deve ser realizado apenas em centros especializados em cirurgia hepatopancreatobiliar minimamente invasiva. A extensão da ressecção hepática é aceitável até que seja alcançada a ressecção R0. A linfadenectomia padrão é indicada para tumores iguais ou superiores a T2, mas a ressecção da via biliar não é recomendada de rotina. Conclusões: Recomendações seguras foram preparadas para carcinoma incidental da vesícula biliar, destacando os mais frequentes tópicos do trabalho diário do cirurgião do aparelho digestivo e hepatopancreatobiliar.


Asunto(s)
Humanos , Femenino , Neoplasias de la Vesícula Biliar , Brasil , Carcinoma , Estudios Retrospectivos , Hallazgos Incidentales , Consenso , Tomografía Computarizada por Tomografía de Emisión de Positrones , Escisión del Ganglio Linfático , Estadificación de Neoplasias
4.
Tree Physiol ; 38(4): 517-530, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29087514

RESUMEN

Tree species in tropical dry forests employ a wide range of strategies to cope with seasonal drought, including regulation of hydraulic function. However, it is uncertain if co-occurring lianas also possess a diversity of strategies. For a taxonomically diverse group of 14 tree and 7 liana species, we measured morphological and hydraulic functional traits during an unusual drought and under non-drought conditions to determine (i) if trees have different water-use strategies than lianas and (ii) if relationships among these traits can be used to better understand how tree and liana species regulate diurnal leaf water potential (Ψdiurnal). In this Costa Rican tropical dry forest, lianas and trees had overlapping water-use strategies, but differed in many leaf economic spectrum traits. Specifically, we found that both lianas and trees employed a diversity of Ψdiurnal regulation strategies, which did not differ statistically. However, lianas and trees did significantly differ in terms of certain traits including leaf area, specific leaf area, petiole length, wood vessel diameter and xylem vessel density. All liana and tree species we measured fell along a continuum of isohydric (partial) to anisohydric (strict or extreme) Ψdiurnal regulation strategies, and leaf area, petiole length, stomatal conductance and wood vessel diameter correlated with these strategies. These findings contribute to a trait-based understanding of how plants regulate Ψdiurnal under both drought stress and sufficient water availability, and underscore that lianas and trees employ a similarly wide range of Ψdiurnal regulation strategies, despite having vastly different growth forms.


Asunto(s)
Hojas de la Planta/fisiología , Árboles/fisiología , Agua/fisiología , Costa Rica
5.
PLoS Negl Trop Dis ; 11(8): e0005693, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28771475

RESUMEN

Venezuelan equine encephalitis (VEE) complex alphaviruses are important re-emerging arboviruses that cause life-threatening disease in equids during epizootics as well as spillover human infections. We conducted a comprehensive analysis of VEE complex alphaviruses by sequencing the genomes of 94 strains and performing phylogenetic analyses of 130 isolates using complete open reading frames for the nonstructural and structural polyproteins. Our analyses confirmed purifying selection as a major mechanism influencing the evolution of these viruses as well as a confounding factor in molecular clock dating of ancestors. Times to most recent common ancestors (tMRCAs) could be robustly estimated only for the more recently diverged subtypes; the tMRCA of the ID/IAB/IC/II and IE clades of VEE virus (VEEV) were estimated at ca. 149-973 years ago. Evolution of the IE subtype has been characterized by a significant evolutionary shift from the rest of the VEEV complex, with an increase in structural protein substitutions that are unique to this group, possibly reflecting adaptation to its unique enzootic mosquito vector Culex (Melanoconion) taeniopus. Our inferred tree topologies suggest that VEEV is maintained primarily in situ, with only occasional spread to neighboring countries, probably reflecting the limited mobility of rodent hosts and mosquito vectors.


Asunto(s)
Virus de la Encefalitis Equina Venezolana/genética , Encefalomielitis Equina Venezolana/epidemiología , Evolución Molecular , Enfermedades de los Caballos/virología , Américas , Secuencia de Aminoácidos , Animales , Culex/virología , Virus de la Encefalitis Equina Venezolana/aislamiento & purificación , Encefalomielitis Equina Venezolana/virología , Enfermedades de los Caballos/epidemiología , Caballos/virología , Humanos , Insectos Vectores/virología , Filogenia
6.
PLoS One ; 12(8): e0183032, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28837674

RESUMEN

The northwestern Gulf of Mexico shelf experiences one of the largest seasonal hypoxic zones in the western hemisphere. Hypoxia (dissolved oxygen, DO ≤ 2.0 mg·L-1) is most severe from May to August during the height of the Gulf shrimp fishery, but its effects on the fishery are not well known. Prior studies indicate that hypoxia alters the spatial dynamics of shrimp and other species through habitat loss and aggregation in nearby oxygenated refuge habitats. We hypothesized that hypoxia-induced changes in the distribution of shrimp also alter the spatial dynamics of the Gulf shrimp fleet. We integrated data on the geographic distribution of shrimp tows and bottom DO to evaluate the effects of hypoxia on spatial patterns in shrimping effort. Our analyses indicate that shrimping effort declines in low DO waters on both the Texas and Louisiana shelf, but that considerable effort still occurs in low DO waters off Louisiana, likely because riverine nutrients fuel both benthic production and low bottom DO in the same general regions. The response of the shrimp fleet to hypoxia on the Louisiana shelf was complex with shifts in effort inshore, offshore, westward, and eastward of the hypoxic zone, as well as to an oxygenated area between two hypoxia regimes associated with the Mississippi and the Atchafalaya River outflows. In contrast, effort on the Texas shelf mostly shifted offshore in response to low DO but also shifted inshore in some years. Spatial patterns in total shrimping effort were driven primarily by the number of shrimp tows, consistent with aggregation of the fleet outside of hypoxic waters, though tow duration also declined in low DO waters. Overall, our results demonstrate that hypoxia alters the spatial dynamics of the Gulf shrimp fishery with potential consequences for harvest interactions and the economic condition of the fishery.


Asunto(s)
Crustáceos , Explotaciones Pesqueras , Oxígeno/análisis , Agua de Mar/química , Navíos , Animales , Monitoreo del Ambiente , Golfo de México
7.
PLoS One ; 7(5): e36731, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22590598

RESUMEN

World food prices hit an all-time high in February 2011 and are still almost two and a half times those of 2000. Although three billion people worldwide use seafood as a key source of animal protein, the Food and Agriculture Organization (FAO) of the United Nations-which compiles prices for other major food categories-has not tracked seafood prices. We fill this gap by developing an index of global seafood prices that can help to understand food crises and may assist in averting them. The fish price index (FPI) relies on trade statistics because seafood is heavily traded internationally, exposing non-traded seafood to price competition from imports and exports. Easily updated trade data can thus proxy for domestic seafood prices that are difficult to observe in many regions and costly to update with global coverage. Calculations of the extent of price competition in different countries support the plausibility of reliance on trade data. Overall, the FPI shows less volatility and fewer price spikes than other food price indices including oils, cereals, and dairy. The FPI generally reflects seafood scarcity, but it can also be separated into indices by production technology, fish species, or region. Splitting FPI into capture fisheries and aquaculture suggests increased scarcity of capture fishery resources in recent years, but also growth in aquaculture that is keeping pace with demand. Regionally, seafood price volatility varies, and some prices are negatively correlated. These patterns hint that regional supply shocks are consequential for seafood prices in spite of the high degree of seafood tradability.


Asunto(s)
Productos Pesqueros/economía , Mercadotecnía/economía , Animales , Costos y Análisis de Costo , Humanos , Naciones Unidas
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