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1.
Ann Bot ; 129(6): 709-722, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33245747

RESUMO

BACKGROUND AND AIMS: The acquisitive-conservative axis of plant ecological strategies results in a pattern of leaf trait covariation that captures the balance between leaf construction costs and plant growth potential. Studies evaluating trait covariation within species are scarcer, and have mostly dealt with variation in response to environmental gradients. Little work has been published on intraspecific patterns of leaf trait covariation in the absence of strong environmental variation. METHODS: We analysed covariation of four leaf functional traits [specific leaf area (SLA) leaf dry matter content (LDMC), force to tear (Ft) and leaf nitrogen content (Nm)] in six Poaceae and four Fabaceae species common in the dry Chaco forest of Central Argentina, growing in the field and in a common garden. We compared intraspecific covariation patterns (slopes, correlation and effect size) of leaf functional traits with global interspecific covariation patterns. Additionally, we checked for possible climatic and edaphic factors that could affect the intraspecific covariation pattern. KEY RESULTS: We found negative correlations for the LDMC-SLA, Ft-SLA, LDMC-Nm and Ft-Nm trait pairs. This intraspecific covariation pattern found both in the field and in the common garden and not explained by climatic or edaphic variation in the field follows the expected acquisitive-conservative axis. At the same time, we found quantitative differences in slopes among different species, and between these intraspecific patterns and the interspecific ones. Many of these differences seem to be idiosyncratic, but some appear consistent among species (e.g. all the intraspecific LDMC-SLA and LDMC-Nm slopes tend to be shallower than the global pattern). CONCLUSIONS: Our study indicates that the acquisitive-conservative leaf functional trait covariation pattern occurs at the intraspecific level even in the absence of relevant environmental variation in the field. This suggests a high degree of variation-covariation in leaf functional traits not driven by environmental variables.


Assuntos
Florestas , Nitrogênio , Ecologia , Fenótipo , Folhas de Planta , Poaceae
2.
Nature ; 525(7567): 100-3, 2015 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26287466

RESUMO

All around the globe, humans have greatly altered the abiotic and biotic environment with ever-increasing speed. One defining feature of the Anthropocene epoch is the erosion of biogeographical barriers by human-mediated dispersal of species into new regions, where they can naturalize and cause ecological, economic and social damage. So far, no comprehensive analysis of the global accumulation and exchange of alien plant species between continents has been performed, primarily because of a lack of data. Here we bridge this knowledge gap by using a unique global database on the occurrences of naturalized alien plant species in 481 mainland and 362 island regions. In total, 13,168 plant species, corresponding to 3.9% of the extant global vascular flora, or approximately the size of the native European flora, have become naturalized somewhere on the globe as a result of human activity. North America has accumulated the largest number of naturalized species, whereas the Pacific Islands show the fastest increase in species numbers with respect to their land area. Continents in the Northern Hemisphere have been the major donors of naturalized alien species to all other continents. Our results quantify for the first time the extent of plant naturalizations worldwide, and illustrate the urgent need for globally integrated efforts to control, manage and understand the spread of alien species.


Assuntos
Biodiversidade , Mapeamento Geográfico , Espécies Introduzidas/estatística & dados numéricos , Plantas , Bases de Dados Factuais , América do Norte , Ilhas do Pacífico , Filogeografia
3.
Ecology ; 100(1): e02542, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30341991

RESUMO

This dataset provides the Global Naturalized Alien Flora (GloNAF) database, version 1.2. GloNAF represents a data compendium on the occurrence and identity of naturalized alien vascular plant taxa across geographic regions (e.g. countries, states, provinces, districts, islands) around the globe. The dataset includes 13,939 taxa and covers 1,029 regions (including 381 islands). The dataset is based on 210 data sources. For each taxon-by-region combination, we provide information on whether the taxon is considered to be naturalized in the specific region (i.e. has established self-sustaining populations in the wild). Non-native taxa are marked as "alien", when it is not clear whether they are naturalized. To facilitate alignment with other plant databases, we provide for each taxon the name as given in the original data source and the standardized taxon and family names used by The Plant List Version 1.1 (http://www.theplantlist.org/). We provide an ESRI shapefile including polygons for each region and information on whether it is an island or a mainland region, the country and the Taxonomic Databases Working Group (TDWG) regions it is part of (TDWG levels 1-4). We also provide several variables that can be used to filter the data according to quality and completeness of alien taxon lists, which vary among the combinations of regions and data sources. A previous version of the GloNAF dataset (version 1.1) has already been used in several studies on, for example, historical spatial flows of taxa between continents and geographical patterns and determinants of naturalization across different taxonomic groups. We intend the updated and expanded GloNAF version presented here to be a global resource useful for studying plant invasions and changes in biodiversity from regional to global scales. We release these data into the public domain under a Creative Commons Zero license waiver (https://creativecommons.org/share-your-work/public-domain/cc0/). When you use the data in your publication, we request that you cite this data paper. If GloNAF is a major part of the data analyzed in your study, you should consider inviting the GloNAF core team (see Metadata S1: Originators in the Overall project description) as collaborators. If you plan to use the GloNAF dataset, we encourage you to contact the GloNAF core team to check whether there have been recent updates of the dataset, and whether similar analyses are already ongoing.

4.
J Surg Res ; 235: 244-249, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30691802

RESUMO

BACKGROUND: Neuroendocrine tumors (NETs) are a relatively rare category of cancers that arise in the gastrointestinal (GI) tract and other organs. Extended hepatectomies including resection of multiple organs are often necessary to achieve negative margins. METHODS: We performed a review of patients undergoing liver resection for NET liver metastases from 2005 to 2015 using National Surgical Quality Improvement Program. We compared patients undergoing hepatectomy alone (HA) versus hepatectomy and a concomitant GI surgery procedure (colorectal, small bowel, and pancreatic) to evaluate postoperative infectious complications. RESULTS: During the study period, 354 patients underwent liver resection for metastatic NET. Hepatectomy alone was performed in 98 patients, and concomitant GI surgery was performed in 256 patients, including 83 colorectal resections (HCCR), 68 small bowel resections, 75 distal pancreatectomies, and 35 pancreaticoduodenectomies (HCPD). Infectious complications were more likely to occur in those undergoing HCPD (60%, P < 0.001), and HCCR (32.5%, P < 0.05) than in those undergoing HA (16.3%). Patients undergoing HCPD and HCCR had a 7.69-fold and 2.52-fold increased risk of infectious complication, respectively, compared with HA after adjustment for other infection risk factors. CONCLUSIONS: Neuroendocrine liver metastases requiring liver resection with concomitant colorectal resection or pancreaticoduodenectomy are at significantly increased risk of developing infectious complications.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Neoplasias Gastrointestinais/cirurgia , Neoplasias Hepáticas/cirurgia , Tumores Neuroendócrinos/cirurgia , Complicações Pós-Operatórias/epidemiologia , Idoso , Feminino , Neoplasias Gastrointestinais/secundário , Humanos , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/secundário , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Estados Unidos/epidemiologia
5.
HPB (Oxford) ; 21(12): 1727-1733, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31229489

RESUMO

BACKGROUND: To study mortality and infectious complications (IC) risk relative to operative duration in a large and contemporary cohort of patients undergoing hepatectomy. METHODS: A retrospective cohort study of 21,443 patients from the National Surgical Quality Improvement Program dataset of patients who underwent liver resection from 2012 to 2016. RESULTS: Patients undergoing hepatectomy during the study period (N = 21,443) had a mean operative duration of 243.5 min of which 16.6% (3533) developed at least one IC. The overall 30-day mortality was 1.6%. A significant increase in mortality and IC was demonstrated from 3 h of operating time (OR: 1.99 and OR: 1.94, respectively), peaking at 8 h (OR: 7.15 and OR: 6.37, respectively). Pneumonia, sepsis/septic shock, and SSI presented high prevalence and were linked to significant mortality. After case-matching, elective hepatectomy was associated with a 4-fold increased risk of infectious complications. CONCLUSIONS: Operative duration was associated with a linear increased risk of mortality and IC after hepatectomy. The most critical determinants of IC were ASA class, COPD, CHF, and type of hepatectomy.


Assuntos
Hepatectomia/mortalidade , Duração da Cirurgia , Pneumonia/mortalidade , Sepse/mortalidade , Choque Séptico/mortalidade , Infecção da Ferida Cirúrgica/mortalidade , Estudos de Coortes , Diabetes Mellitus/epidemiologia , Feminino , Insuficiência Cardíaca/epidemiologia , Hepatectomia/métodos , Humanos , Hipertensão/epidemiologia , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Estudos Retrospectivos , Fumar/epidemiologia , Estados Unidos/epidemiologia
6.
HPB (Oxford) ; 21(8): 1009-1016, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30765199

RESUMO

BACKGROUND: We aimed to study outcomes in HIV + patients with HCC in the US following Liver Transplantation (LT) using the UNOS dataset. METHODS: The database was queried from 2003 to 2016 for patients undergoing LT with HCC, HIV+, and HCC/HIV+. RESULTS: Out of 17,397 LT performed for HCC during the study period, 113 were transplanted for HCC with HIV infection (91 isolated livers). Patients transplanted for HCC/HIV+ were younger (55.54 ± 5.89 vs 58.80 ± 7.37, p < 0.001), had lower total bilirubin (1.20 vs 1.60, p = 0.042) significantly lower BMI (25.35 ± 4.43 vs 28.39 ± 5.17, p < 0.001) and were more likely to be co-infected with HBV (25.3% vs 8.2% p < 0.001) than those transplanted for HCC alone. HCC/HIV + patients were found to have a 3.8 fold increased risk of peri-operative mortality at 90 days after matching. HCC/HIV + recipients had 54% decreased long-term survival within the HCC cohort. Our initial analysis of overall graft and patient survival found significant differences between HCC/HIV and HCC/HIV + recipients. However, these variances were lost after case-matching. Recurrence and disease free survival were similar in HCC alone vs HCC/HIV + recipients. CONCLUSIONS: Our analysis suggests that excellent outcomes can be achieved in selected patients with HCC/HIV+.


Assuntos
Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , Infecções por HIV/mortalidade , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/virologia , Transplante de Fígado/efeitos adversos , Adulto , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Causas de Morte , Estudos de Coortes , Bases de Dados Factuais , Feminino , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Infecções por HIV/patologia , Infecções por HIV/cirurgia , Hepatectomia/métodos , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Estatísticas não Paramétricas , Análise de Sobrevida , Fatores de Tempo , Estados Unidos
7.
J Clin Imaging Sci ; 15: 59, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36601423

RESUMO

Emphysematous pyelonephritis (EPN) is a necrotizing renal infection that can rapidly progress without urgent intervention. The purpose of this study was to evaluate the safety and efficacy of percutaneous nephrostomy (PN) in the management of EPN, as well as the relationship of outcomes with initial classification by the Huang-Tseng classification system and other prognostic factors such as thrombocytopenia. A retrospective review of medical records revealed seven patients with EPN treated with PN. Thirty-day survival rate was 86%, with the only mortality due to an arrhythmia secondary to underlying cardiomyopathy rather than a complication from EPN or PN. A single nephrostomy procedure served as definitive treatment in 3 patients (43%). Reintervention due to recurrence of EPN symptoms was required in 4 patients (57%), all of which initially presented with Class 3 disease or higher. Two of these four patients required nephrectomy, while the other two were successfully managed with a second drainage procedure without further recurrence of symptoms. PN appears to be a safe and generally effective management option for EPN, especially in patients who are considered poor surgical candidates. PN may serve as definitive treatment in hemodynamically stable patients with lower class of disease. In patients with higher class of disease, PN may be definitive treatment in patients who lack additional risk factors such as thrombocytopenia or serve as an effective bridge to nephrectomy.

8.
Surgery ; 168(3): 462-470, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32418709

RESUMO

BACKGROUND: The obesity epidemic has spread rapidly across the United States. Although overweight and obese patients have a paradoxically lower risk for postoperative morbidity and mortality, the risks associated with extreme classes of obesity (morbid obesity, super obesity, and super-super obesity) have not been described. METHODS: We queried the National Surgical Quality Improvement Program database from 2012 to 2016. Of 1,815,251 surgical cases, there were 3,946 vascular cases, 237,777 emergency procedures, and 75,177 cases with missing data that were removed. The remaining 1,378,711 cases were included in this analysis. Multivariable linear and logistic regression was performed to assess the impact of body mass index on postoperative outcomes. RESULTS: Patients within the super obesity and super-super obesity groups had the highest procedure-adjusted mortality risk among all body mass index classes (odds ratio = 2.31 and 2.63, respectively). Morbid obesity and underweight groups had moderate risk (odds ratio = 1.37 and 1.88, respectively), while those in the overweight and obesity class I and II cohorts had improved or equivocal mortality risk compared to normal body mass index class patients. Risk-adjusted and unadjusted multivariable models demonstrated that extreme obesity classes (morbid obesity, super obesity, and super-super obesity) have a graduated escalation of perioperative morbidity, infectious, and critical care complications. CONCLUSION: Further detailing extreme obesity-related risk beyond the obesity class III umbrella is necessary for accurate risk prediction, especially with the rising prevalence of elective nonbariatric surgery in this population. Preoperative risk assessment tools should consider subgroup risk adjustment to delineate true postoperative complication risk, facilitate patient education, and address modifiable risk factors before surgery.


Assuntos
Procedimentos Cirúrgicos Eletivos/efeitos adversos , Obesidade Mórbida/complicações , Período Perioperatório/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/diagnóstico , Obesidade Mórbida/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Estudos Retrospectivos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Estados Unidos/epidemiologia
9.
Am J Surg ; 218(1): 151-156, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30528789

RESUMO

OBJECTIVE: To determine predictors of critical care complications (CCC) in patients undergoing hepatectomy. METHODS: All hepatectomy patients in NSQIP from 2012 to 2016 were analyzed. CCC included prolonged ventilation (>48 h), sepsis/septic shock, renal failure/insufficiency, cardiac arrest/AMI and pulmonary embolism. RESULTS: A total of 21,443 patients underwent hepatectomy during the study period. Overall rate of CCC was 11%, with the most common being sepsis/septic shock (6.1%) and respiratory failure (4.9%). On multivariate analysis the preoperative risk factors associated with CCC included ASA Class IV-V (OR:2.04, p < 0.0001), diabetes (OR = 1.28, p = 0.0001), pre-operative ventilator use (OR: 17.75, p = 0.0003); COPD (OR: 1.65, p < 0.0001); pre-operative weight loss >10% (OR: 1.35, p = 0.0026); pre-operative sepsis (OR: 2.14, p < 0.0001). Propensity score matched analysis demonstrated a significant increased risk of mortality in patients with CCC (OR: 26.75, p < 0.0001) and a prolonged LOS of 10.5 days above the mean (ß Estimate: 10.51, p < 0.0001). CONCLUSIONS: ASA class, diabetes, COPD, pre-operative weight loss >10% and pre-operative sepsis are the strongest predictors of CCC after hepatectomy. The presence of CCC significantly increased the risk of peri-operative mortality 26-fold.


Assuntos
Hepatectomia/mortalidade , Tempo de Internação/estatística & dados numéricos , Complicações Pós-Operatórias/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos
10.
PLoS One ; 14(2): e0212538, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30794613

RESUMO

Autophagy targets cellular components for lysosomal-dependent degradation in which the products of degradation may be recycled for protein synthesis and utilized for energy production. Autophagy also plays a critical role in cell homeostasis and the regulation of many physiological and pathological processes and prompts this investigation of new agents to effect abnormal autophagy in hepatocellular carcinoma (HCC). 2,5-Dichloro-N-(2-methyl-4-nitrophenyl) benzenesulfonamide (FH535) is a synthetic inhibitor of the Wnt/ß-catenin pathway that exhibits anti-proliferative and anti-angiogenic effects on different types of cancer cells. The combination of FH535 with sorafenib promotes a synergistic inhibition of HCC and liver cancer stem cell proliferation, mediated in part by the simultaneous disruption of mitochondrial respiration and glycolysis. We demonstrated that FH535 decreased HCC tumor progression in a mouse xenograft model. For the first time, we showed the inhibitory effect of an FH535 derivative, FH535-N, alone and in combination with sorafenib on HCC cell proliferation. Our study revealed the contributing effect of Wnt/ß-catenin pathway inhibition by FH535 and its derivative (FH535-N) through disruption of the autophagic flux in HCC cells.


Assuntos
Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Sulfonamidas/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Camundongos , Camundongos Nus , Sorafenibe/administração & dosagem , Via de Sinalização Wnt/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/antagonistas & inibidores , beta Catenina/genética , beta Catenina/metabolismo
11.
Dig Liver Dis ; 50(11): 1115-1123, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30217732

RESUMO

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths and the fifth most common cancer worldwide. Most of these patients are seen with advanced disease at the time of presentation. In spite of its high prevalence, there are not many therapeutic options available for patients with advanced-stage HCC. There is an urgent need for improving early detection and prognostication of patients with HCC. In addition, the development of new therapies targeting specific pathways involved in the pathogenesis of HCC should be a major goal for future research, with the objective of improving outcomes of patients with HCC. Biomarkers represent a relatively easy and noninvasive way to detect and estimate disease prognosis. In spite of the numerous efforts to find molecules as possible biomarkers, there is not a single ideal marker in HCC. Many new findings have shown promising results both in diagnosing and treating HCC. In this review, we summarized the most recent and relevant biomarkers in HCC.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Detecção Precoce de Câncer/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Prognóstico , Microambiente Tumoral
12.
Environ Entomol ; 39(6): 1848-57, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22182550

RESUMO

The introduced plant Miconia calvescens (Melastomataceae) poses a grave threat to Hawaii's native ecosystems and biodiversity. One potential candidate for classical biological control is Cryptorhynchus melastomae (Coleoptera: Curculionidae: Cryptorhynchinae), a stem-boring weevil from Central and South America. This weevil feeds on M. calvescens in its native Costa Rica and has been successfully reared under greenhouse conditions. Comparison of its environmental conditions in Costa Rica with those in the Miconia infested areas of Hawaii indicates the latter is a suitable habitat for C. melastomae. C. melastomae has one or two generations per year. Adults feed on new stems, petioles, leaf buds, veins, and lamina, whereas larvae mine the stem until pupation. Adults appear to prefer saplings for oviposition and feeding. Under greenhouse conditions both adults and larvae can seriously damage and kill small M. calvescens. Preliminary host testing indicates that C. melastomae may be family specific on Melastomataceae. However, because Hawaii lacks native melastomes and has many other serious melastome weeds, a family specific insect may be suitable as a biocontrol agent in this case.


Assuntos
Especificidade de Hospedeiro , Espécies Introduzidas , Melastomataceae/parasitologia , Controle Biológico de Vetores , Gorgulhos/fisiologia , Animais , Costa Rica , Feminino , Geografia , Havaí , Herbivoria , Masculino , Oviposição
14.
Medisan ; 13(5)sept.-oct. 2009. tab
Artigo em Espanhol | LILACS | ID: lil-548039

RESUMO

Se hizo un ensayo clinicoterapéutico en 60 pacientes atendidos en la consulta de Dermatología del Hospital Provincial Docente Dr Joaquín Castillo Duany de Santiago de Cuba, durante el 2008, con el fin evaluar la efectividad de la pomada de urea en las verrugas plantares. Se conformaron 2 grupos (de estudio y control): los primeros recibieron pomada de urea al 20 por ciento y los segundos pomada salicílica al 40 por ciento. La pomada de urea resultó más eficaz para eliminar las manifestaciones clínicas de esa lesión, en un período de 6 a 8 semanas y no hubo reacciones adversas.


A clinical therapeutical trial was made in 60 patients assisted at the Dermatology department of Dr Joaquín Castillo Duany Teaching Provincial Hospital from Santiago de Cuba, during 2008, aimed at evaluating the effectiveness of the urea ointment in the feet warts. They conformed to 2 groups (study and control): the first group received urea ointment at 20 percent and the second one salicylic ointment at 40 percent. The urea ointment was more effective to eliminate the clinical manifestations of that lesion, in a period of 6 to 8 weeks and there were not adverse reactions.


Assuntos
Humanos , Masculino , Adulto , Feminino , Ácido Salicílico/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Química Farmacêutica , Dermatopatias Virais/tratamento farmacológico , Pomadas/uso terapêutico , Ureia/uso terapêutico , Verrugas/tratamento farmacológico
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