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1.
PLoS One ; 14(9): e0221705, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31509559

RESUMO

Agricultural development was the major contributor to South America's designation as the continent with the highest rates of forest loss from 2000-2012. As the apex predator in the Neotropics, jaguars (Panthera onca) are dependent on forest cover but the species' response to habitat fragmentation in heterogeneous agricultural landscapes has not been a subject of extensive research. We used occupancy as a measure of jaguar habitat use in Colombia's middle Magdalena River valley which, as part of the intercontinental Tumbes-Chocó-Magdalena biodiversity hotspot, is exceedingly fragmented by expanding cattle pastures and oil palm plantations. We used single-season occupancy models to analyze 9 months of data (2015-2016) from 70 camera trap sites. Given the middle Magdalena's status as a "jaguar corridor" and our possible violation of the occupancy models' demographic closure assumption, we interpreted our results as "probability of habitat use (Ψ)" by jaguars. We measured the associations between jaguar presence and coverage of forest, oil palm, and wetlands in radii buffers of 1, 3, and 5 km around each camera trap. Our camera traps recorded 77 jaguar detections at 25 of the camera trap sites (36%) during 15,305 trap nights. The probability of detecting jaguars, given their presence at a site, was 0.28 (0.03 SE). In the top-ranked model, jaguar habitat use was positively influenced by wetland coverage (ß = 7.16, 3.20 SE) and negatively influenced by cattle pastures (ß = -1.40, 0.63 SE), both in the 3 km buffers. We conclude that wetlands may serve as keystone habitats for jaguars in landscapes fragmented by cattle ranches and oil palm plantations. Greater focus on wetland preservation could facilitate jaguar persistence in one of the most important yet vulnerable areas of their distribution.


Assuntos
Conservação dos Recursos Naturais/métodos , Panthera/fisiologia , Animais , Biodiversidade , Colômbia , Ecossistema , Feminino , Masculino , Densidade Demográfica , Gravação em Vídeo , Áreas Alagadas
2.
Rev. biol. trop ; 66(4): 1741-1753, oct.-dic. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1003360

RESUMO

Abstract The umbrella species concept posits that protection of a single, wide-ranging species may confer protection to a large number of sympatric species. Due to their large home ranges, widespread distribution in the Mesoamerican Biodiversity Hotspot (MBH), and status as the focal species of numerous conservation initiatives, the jaguar Panthera onca is an ideal species to evaluate the umbrella strategy. After ground-truthing jaguar corridors from 2009-2016, we tested the umbrella value of jaguars for endemic herpetofauna (Amphibia, Reptilia) in Nuclear Central America (NCA), a ~ 370 000 km² sub-region of the MBH. NCA contains the greatest density of threatened reptiles in the Western Hemisphere and harbors extraordinary high diversity of amphibians, the most threatened class of vertebrate worldwide. Of the 304 regional endemics in NCA, the distributions of 187 (61.5 %) species of amphibians and reptiles overlapped ground-truthed jaguar range. The distributions of 14 reptiles, including a critically endangered Bothriechis spp. and two endangered Norops spp., occur exclusively within jaguar distribution. Similarly, the distributions of 19 amphibians, including four critically endangered Craugastor spp. and two critically endangered Plectrohyla spp. occur entirely within jaguar distribution. Our results indicate greater effectiveness of ground-truthed jaguar distribution than modeled and randomly selected networks in overlapping the distributions of endemic herpetofauna, especially threatened amphibians, in NCA. Substantiation of multi-taxa dependence on habitat in jaguar distribution would strengthen justification for wider application of the umbrella strategy beyond NCA and aid conservation planning in the MBH.


Resumen Las especies sombrilla son aquellas cuya conservación confiere protección a un gran número de especies simpátricas. Debido a sus ámbitos hogareños extensos, a una distribución generalizada en el Hotspot de Biodiversidad de Mesoaméricana (MBH), y su estatus como especie focal de numerosas iniciativas de conservación, el jaguar Panthera onca es una especie ideal para evaluar la estrategia sombrilla. Evaluamos el valor de los jaguares como estrategia sombrilla para la herpetofauna endémica en Centro América Nuclear (NCA), una subregión de ~ 370 000 km² que se encuentra dentro del MBH. La NCA contiene la mayor densidad de reptiles amenazados en el hemisferio occidental y alberga una diversidad extraordinaria de anfibios, que es la clase de vertebrados más amenazada del mundo. De las 304 especies endémicas regionales presentes en el NCA, las distribuciones de 187 (61.5 %) se sobrepusieron al área de distribución del jaguar verificada. Las distribuciones de 14 reptiles, incluyendo una Bothriechis spp. (en Peligro Crítico) y dos Norops spp. (en Peligro de Extinción), se dan exclusivamente dentro del rango del jaguar. Similarmente, 19 especies de anfibios, incluidas cuatro Craugastor spp. (en Peligro Crítico) y dos Plectrohyla spp. (en Peligro Crítico) están presentes exclusivamente dentro del área de distribución del jaguar. Nuestros resultados indican que los corredores verificados para el jaguar coinciden mejor con las distribuciones de la herpetofauna endémica dentro del NCA, especialmente anfibios, en comparación con los corredores modelados y seleccionados al azar. La confirmación del traslape de la distribución del hábitat del jaguar con la de múltiples taxones fortalece la justificación de una aplicación más amplia de la estrategia sombrilla, aún más allá del NCA, contribuyendo también en la selección de áreas de conservación previamente subestimadas dentro del MBH.


Assuntos
Animais , Fauna , Terminalia , Panthera , Anfíbios , América Central
3.
J Pediatr Urol ; 14(1): 48.e1-48.e7, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28822627

RESUMO

OBJECTIVE: Appendicovesicostomy (APV) and Monti ileovesicostomy (Monti) are durable catheterizable channels. While subfascial revision rates vary by channel type, a channel implanted in the anterior (vs posterior) aspect of the bladder may have a lower subfascial revision risk, due to decreased channel mobility and better fascial fixation. The present study aimed to compare long-term durability of anteriorly compared to posteriorly implanted APV and Monti channels in a large international cohort. MATERIALS AND METHODS: A retrospective cohort study was conducted on patients aged ≤21 years and who underwent APV or Monti surgery with an open technique at three high-volume centers (1990-2015). The following were noted: patient demographics, stomal and subfascial revisions, stomal location, channel placement (anterior/posterior), and channel type - APV, spiral Monti to umbilicus (SMU), other Monti channels. Survival analysis and Cox proportional hazards regression were used to separately examine the three channel groups. RESULTS: Of the 675 patients who met inclusion criteria, 387 had an APV (71.3% anterior), 53 had an SMU (13.2% anterior) and 235 had other Monti channels (42.1% anterior). Median age at surgery was 8.8 years for APV (median follow-up: 5.5 years), 9.2 years for other Monti (follow-up: 6.6 years) and 7.9 years for SMU (follow-up: 9.0 years). Patients originated from the USA (67.9%), Argentina (26.4%) and Chile (5.8%). Overall, 76 stomal and 77 subfascial revisions occurred. Risk of stomal revision was 9.3-12.0% at 5 years of follow-up, and was similar between channel types or location (P = 0.57). Risk of subfascial revision at 5 years was 7.4% for APV, 12.7% for all other Monti channels and 25.9% for SMU (P = 0.001). On survival analysis, stomal and subfascial revision rates were similar between anterior and posterior channels for APV (P ≥ 0.16), other Monti channels (P ≥ 0.62) and SMU (P ≥ 0.43) (Summary Fig.). On multivariate regression, channel configuration was not associated with stomal or subfascial revision for APV (P ≥ 0.18) or other Monti channels (P ≥ 0.64). Sex, age, diagnosis, country and stomal location were not associated with revision risk (P ≥ 0.06). DISCUSSION: Contrary to the hypothesis, subfascial revision rates were no different between anterior and posterior channels. Given that many reported outcomes related to genitourinary reconstruction occur rarely and require prolonged follow-up, collaborative research in this area should be encouraged. CONCLUSIONS: The study demonstrated durable long-term results with the APV and Monti techniques in an international cohort. Risks of stomal and subfascial complications were not significantly different between anteriorly and posteriorly implanted channels. As previously reported, Monti channels, particularly SMU, were more prone to undergoing subfascial revisions.


Assuntos
Cistostomia/métodos , Cateterismo Urinário/métodos , Derivação Urinária/métodos , Coletores de Urina , Procedimentos Cirúrgicos Urológicos/métodos , Adolescente , Fatores Etários , Argentina , Criança , Pré-Escolar , Chile , Estudos de Coortes , Cistostomia/efeitos adversos , Seguimentos , Humanos , Internacionalidade , Masculino , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Modelos de Riscos Proporcionais , Reoperação/métodos , Estudos Retrospectivos , Medição de Risco , Fatores Sexuais , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos , Procedimentos Cirúrgicos Urológicos/efeitos adversos , Adulto Jovem
4.
Rev. chil. urol ; 77(2): 137-140, 2012.
Artigo em Espanhol | LILACS | ID: lil-783400

RESUMO

La resolución quirúrgica de una obstrucción pieloureteral (OPU), con mayor frecuencia se realiza de forma laparoscópica. Siendo un procedimiento difícil per-se, consideramos que para optimizar tiempos, materiales y esfuerzo es necesario involucrar a todo el equipo quirúrgico. Se evalúa protocolo quirúrgico prospectivo, con ajuste de protocolo a mitad del estudio en post de mejorar los tiempos quirúrgicos. Método: Estudio prospectivo de 12 casos de pacientes >5kg con OPU y MA G3 con dificultad de vaciamiento; en quienes se aplicó el protocolo quirúrgico para pieloplastia laparoscópica (pasos quirúrgicos, características de suturas, pig-tail y material quirúrgico). Todos los casos fueron operados por 2 cirujanos con experiencia laparoscópica urológica avanzada (>5 años); un mismo ayudante y dos instrumentistas. Después de los primeros 6 pacientes (grupo A) se analizó y perfeccionó el protocolo quirúrgico, comparando posteriormente resultados y en especial tiempo quirúrgico con los siguientes 6 (grupo B). Resultados: La serie incluyó 9 hombres. La mediana para edad fue de 9.3 meses. El peso promedio fue 16. 7 kg (20.4 vs 13.1 kg respectivamente). En grupo A se realizaron 4 derechas y 2 izquierdas, y el grupo B fue inverso (4 izquierdas). Tres de doce pacientes presentaban OPU secundaria a vasos aberrantes. El tiempo quirúrgico promedio por grupo fue de 171.2 (120-200 min) vs 141.7 (90-210 min) respectivamente. El seguimiento promedio fue 19.6 meses (13-24 meses), todos los pacientes tuvieron buena evolución, con MA G-3 sin obstrucción al vaciamiento y disminución de la hidronefrosis. Conclusiones: Consideramos que la disminución del tiempo quirúrgico en el segundo grupo se debió tanto a la integración del equipo como al perfeccionamiento del protocolo quirúrgico: en la técnica, colocación de un cuarto trocar, forma de colocar pig-tail, tipo y tamaño de suturas, preparación...


Laparoscopic surgical resolution for an ureteropelvic junction obstruction (UPJO) is being widely used around the world. lt is considered as a hard and difficult procedure per-se, we considered for time, materials and effort Optimization; to involve every single member of the surgical team. A surgical protocol was developed and revised, with some adjustments in the middle looking forward to reduce surgical time. Method: Prospective study including 12 patients <5kg weight with UPJO and difficult emptying MA G-3; to whom a surgical protocol for laparoscopic pyeloplasty was applied (surgical steps, suture characteristics, stent and surgical material). All cases were operated by 2 advanced skilled laparoscopic surgeons (>5 year experience); same assistant surgeon and two different surgical assistants. After the first 6 cases (group A) the protocol was revised and improved, comparing results especially surgical time with group B (n=6). Results: The series included 9 male, median ages was 9.3 months. Average weight was 16. 7 kg (20.4 vs 13.1 kg for each group). Four right-sided pyeloplasties and 2 left-sided were performed in group A, and opposite in group B (4 left-side). Three of twelve patients had UPJO secondary to polar vessels. The mean surgical time was 171.2 ( 120-200 min) vs 141. 7 (90-210 min) respective/y. Mean follow-up was 19.6 months (13-24 mo), all patients had good outcome, without obstruction in the MA G-3 study and regression of the hydronephrosis...


Assuntos
Humanos , Masculino , Feminino , Lactente , Laparoscopia/métodos , Obstrução Ureteral/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Estudos Prospectivos , Seguimentos , Duração da Cirurgia
5.
Rev. chil. urol ; 77(2): 105-110, 2012. tab
Artigo em Espanhol | LILACS | ID: lil-783394

RESUMO

La instalación de catéteres venosos centrales (CVC) para hemodiálisis es parte de la práctica habitual en los servicios de nefrourologia pediátrica. Sin embargo, aún no existen suficientes reportes sobre resultados exitosos con los catéteres de hemodiálisis (HD) en < 15 kg. Nuestro objetivo es reportar la sobrevida y el desarrollo de complicaciones de los CVC insertados en niños <15 kg y evaluar si su uso es seguro en pediatría. Método: Se realizó un seguimiento prospectivo de los pacientes con enfermedad renal crónica terminal (ERC T), con peso < 15 kg, en quienes se instaló un CVC de hemodiálisis tunelizado por punción, entre julio 2006 y junio 2011. Se analizaron variables como: género, enfermedad de base, edad y peso al inicio de HD, resultado de la HD, sitio de inserción, número de catéteres por paciente, motivo de retiro y tiempo de sobrevida del catéter. Resultados: Durante un periodo de 60 meses, se instalaron 31 CVC en 11 pacientes < 15 kg, 8 hombres y 3 mujeres. La principal causa de ERCT es displasia renal. Al inicio de la HD, la edad promedio de los pacientes fue de 27 meses (5-6om) y la media de peso de 10 kg (4. 5-13 kg). El principal sitio de inserción fue la vena yugular interna (90 por ciento). La duración media de HD fue de 312 días (26-840 días).En promedio se requirieron 2.5 catéteres por paciente (rango 1-5). Los factores mecánicos (trombosis, desplazamiento o acodadura), fueron la principal causa de retiro del catéter (39 por ciento), seguidos por las infecciones (13 por ciento). La sobrevida promedio fue de 110 días/catéter (0 a 586)...


Placement of central venous catheters (C VC) for hemodialysis is part of the usual practice of the pediatric nephron urology services. However, there are few data in the literature documenting successful results with the catheters of hemodialysis (HD) in patients weighing less than 15 kg. Our aim is to report the survival and complications of CVC insertion in children weighing less than 15 kg and to assess whether their use is suitable and safe in low-weight pediatric patients. Methods: Prospective follow-up of patients with end-stage renal disease (ESRD), weighing less than 15 kg, in whom a tunneled hemodialysis CVC was inserted, between July 2006 and June 2011. The following data is gathered: gender, underlying cause of chronic kidney disease, age and weight at the beginning of hemodialysis, catheter location, and duration of HD and reason for discontinuing it, number of catheters used per patient, reasons for removal, and catheter survival. Results: During a period of 60 months, 11 CVC were placed in 31 patients weighing less than 15 kg (8 boys and 3 girls). The main cause of ESRD was renal dysplasia. Mean age at start of dialysis was 27 months (5-60 m) and mean weight was 10 kg (4.5-13 kg). The main catheter location was the internal jugular vein (90 percent). The mean duration of HD was 312 days (26-840 days). An average of 2.5 catheters was required per patient (range 1-5). Mechanical factors (thrombosis, displacement or Layering) were the most common cause of central-line removal (39 percent), followed by infections (13 percent). Mean catheter survival was 110 days/ catheter (range 0-586)...


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Cateteres Venosos Centrais/efeitos adversos , Diálise Renal/métodos , Falência Renal Crônica/terapia , Estudos Prospectivos , Seguimentos , Peso Corporal
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