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2.
Biol Lett ; 19(6): 20230124, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37340808

RESUMEN

Fossil cetaceans are often found in Miocene marine outcrops across the globe. However, because this record is not homogeneous, the dissimilar increase in occurrences, along with the sampling bias has created regions with extensive records and others with great scarcity. Among these, the Caribbean has remained enigmatic due to the lack of well-preserved cetacean fossils. Here, we report new Caribbean fossil cetaceans from the Upper Miocene Chagres Formation exposed along Piña beach, Eastern Panama, including a scaphokogiine kogiid, an Acrophyseter-like physeteroid and the phocoenid Piscolithax. Along with previous records of the iniid Isthminia panamensis and the kogiine Nanokogia isthmia, the Chagres cetacean fauna shows some similarities with other Late Miocene cetacean communities such as the Californias in the North Pacific, although their closest affinities lie with the eastern South Pacific Pisco Formation, Peru. Such findings indicate that though deep and intermediate Caribbean-Pacific water interchange was reduced by the Middle Miocene due to the shallowing of the Central American Seaway, shallow waters marine connection that persisted until the Pliocene might have facilitated the dispersal of coastal species across both sides of the Isthmus.


Asunto(s)
Colon , Fósiles , Panamá , Océanos y Mares , Región del Caribe
3.
PeerJ ; 8: e9051, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32391203

RESUMEN

The occurrence and diversity of elasmobranchs from the Oligocene-Miocene boundary from Tropical America is poorly known in comparison with the paleodiversity from younger Neogene intervals of the region. Here we describe a new elasmobranch assemblage from the rich fossil site of Montañita-Olón (Dos Bocas Formation, Santa Elena, Ecuador), where other vertebrates have already been described: for example, sea turtles and cetaceans. We report a total of 27 elasmobranch taxa, 19 of which are new fossil records for Ecuador, 10 new records for the Central Eastern Pacific and four new records for South America. Additionally, in order to reconstruct the environment where these marine remains were deposited, we performed abundance, paleobathymetric and habitat preference analyses, concluding that they were likely deposited in an outer neritic (open shelf) environment. The study of Oligocene and early Miocene marine elasmobranchs faunas in Tropical America is key to addressing the issues in the evolutionary history of this group.

5.
Med Clin (Barc) ; 153(12): 473, 2019 12 27.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31277881
6.
Environ Res Lett ; 12(3): 034027, 2017 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-28855959

RESUMEN

Recent studies projecting future climate change impacts on forests mainly consider either the effects of climate change on productivity or on disturbances. However, productivity and disturbances are intrinsically linked because 1) disturbances directly affect forest productivity (e.g. via a reduction in leaf area, growing stock or resource-use efficiency), and 2) disturbance susceptibility is often coupled to a certain development phase of the forest with productivity determining the time a forest is in this specific phase of susceptibility. The objective of this paper is to provide an overview of forest productivity changes in different forest regions in Europe under climate change, and partition these changes into effects induced by climate change alone and by climate change and disturbances. We present projections of climate change impacts on forest productivity from state-of-the-art forest models that dynamically simulate forest productivity and the effects of the main European disturbance agents (fire, storm, insects), driven by the same climate scenario in seven forest case studies along a large climatic gradient throughout Europe. Our study shows that, in most cases, including disturbances in the simulations exaggerate ongoing productivity declines or cancel out productivity gains in response to climate change. In fewer cases, disturbances also increase productivity or buffer climate-change induced productivity losses, e.g. because low severity fires can alleviate resource competition and increase fertilization. Even though our results cannot simply be extrapolated to other types of forests and disturbances, we argue that it is necessary to interpret climate change-induced productivity and disturbance changes jointly to capture the full range of climate change impacts on forests and to plan adaptation measures.

7.
Cir Cir ; 85 Suppl 1: 44-48, 2017 Dec.
Artículo en Español | MEDLINE | ID: mdl-28062078

RESUMEN

BACKGROUND: Dengue is the most important human viral disease transmitted by mosquitoes. It can be asymptomatic or it can present in any of its 3clinical forms: Dengue fever, dengue haemorrhagic fever and dengue shock syndrome. However, some atypical manifestations have been reported in surgical emergencies caused by acute appendicitis in patients with dengue fever. CLINICAL CASE: We report the case of an 18-year-old Mexican male who presented to the emergency department of the General Hospital of Culiacan, Sinaloa, with symptoms of dengue fever, accompanied by crampy abdominal pain with positive Rovsing and Dunphy signs. Dengue infection was confirmed by a positive NS1 antigen test performed by enzyme-linked immunosorbent assay. An abdominal ultrasound revealed an appendicular process; as the abdominal pain in the right side kept increasing, an open appendectomy was performed. Abundant inflammatory liquid was observed during the surgery, and the pathology laboratory reported an oedematous appendix with fibrinopurulent plaques, which agreed with acute ulcerative appendicitis. The patient was discharged fully recovered without complications during the follow-up period. CONCLUSIONS: Acute abdominal pain can be caused in some cases by dengue infection. This can be confusing, which can lead to unnecessary surgical interventions, creating additional morbidities and costs for the patient. This unusual and coincident acute appendicitis with dengue highlights the importance of performing careful clinical studies for appropriate decision making, especially in dengue endemic regions during an outbreak of this disease.


Asunto(s)
Apendicitis/complicaciones , Dengue/complicaciones , Abdomen Agudo/etiología , Dolor Abdominal/diagnóstico , Adolescente , Antígenos Virales/sangre , Apendicectomía , Apendicitis/diagnóstico , Apendicitis/diagnóstico por imagen , Apendicitis/cirugía , Virus del Dengue/inmunología , Diagnóstico Diferencial , Urgencias Médicas , Fiebre/etiología , Humanos , Masculino , Ultrasonografía
13.
PLoS One ; 10(4): e0123909, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25923213

RESUMEN

Kogiids are known by two living species, the pygmy and dwarf sperm whale (Kogia breviceps and K. sima). Both are relatively rare, and as their names suggest, they are closely related to the sperm whale, all being characterized by the presence of a spermaceti organ. However, this organ is much reduced in kogiids and may have become functionally different. Here we describe a fossil kogiid from the late Miocene of Panama and we explore the evolutionary history of the group with special attention to this evolutionary reduction. The fossil consists of cranial material from the late Tortonian (~7.5 Ma) Piña facies of the Chagres Formation in Panama. Detailed comparison with other fossil and extant kogiids and the results of a phylogenetic analysis place the Panamanian kogiid, herein named Nanokogia isthmia gen. et sp. nov., as a taxon most closely related to Praekogia cedrosensis from the Messinian (~6 Ma) of Baja California and to Kogia spp. Furthermore our results show that reduction of the spermaceti organ has occurred iteratively in kogiids, once in Thalassocetus antwerpiensis in the early-middle Miocene, and more recently in Kogia spp. Additionally, we estimate the divergence between extant species of Kogia at around the late Pliocene, later than previously predicted by molecular estimates. Finally, comparison of Nanokogia with the coeval Scaphokogia cochlearis from Peru shows that these two species display a greater morphological disparity between them than that observed between the extant members of the group. We hypothesize that this reflects differences in feeding ecologies of the two species, with Nanokogia being more similar to extant Kogia. Nanokogia shows that kogiids have been part of the Neotropical marine mammal communities at least since the late Miocene, and gives us insight into the evolutionary history and origins of one of the rarest groups of living whales.


Asunto(s)
Evolución Biológica , Fósiles/anatomía & histología , Ballenas/anatomía & histología , Animales , América Central , Vida , Panamá , Perú , Filogenia , Cráneo/anatomía & histología , Especificidad de la Especie , Ballenas/genética
15.
Rev. biol. trop ; 60(2): 893-908, June 2012. graf, mapas, tab
Artículo en Español | LILACS | ID: lil-657827

RESUMEN

Environmental response in the Pacific to aseismic Cocos Ridge subduction (Panama and Costa Rica). The evolution of the marine communities along the Pacific coast of Central America, may have changed in response to the formation of the Isthmus of Panama. To evaluate the effect of the Aseismic Cocos Ridge (DAC) subduction on the marine benthic communities, we reconstructed benthic assemblages from Neogene fossiliferous formations in Burica and Nicoya peninsulas of Panama and Costa Rica. Paleoecological and paleoenvironmental conditions were reconstructed by comparing community structure from bulk fossil samples with dredge collections from modern Tropical American seas, using principal component analysis. Our results indicate that during the early Pliocene, before the closing of the Isthmus, some oceanic islands existed with moderate upwelling in the Burica region. After the closure, during the late Pliocene and early Pleistocene the collision of the DAC caused an uplift of the seafloor, where water depth of 2 300m became shallow waters of less than 40m depth. Meanwhile, upwelling intensified in the open ocean the uplift that had formed small islands in coastal areas of Burica, creating protected areas and limiting the upwelling effect that was given in open ocean. The subduction of the DAC continued until the islands were joined to the mainland and gradually disappeared, allowing the return of the upwelling. During the middle Pleistocene a second process of accelerated uplift ith speeds of 8m/1 000 years provoked again the elevation of the seafloor and later the elevation of the Talamanca Range. The new range formed a barrier that blocked the passage of the Trade winds, created new ecological conditions and optimized and allowed the growth of the best coral reefs in the coasts of the tropical Eastern Pacific (POT) between Panama and Costa Rica. Rev. Biol. Trop. 60 (2): 893-908. Epub 2012 June 01.


Con el fin de evaluar el efecto de la Subducción de la Dorsal Asísmica de Cocos (DAC) durante las etapas finales de la formación del Istmo. Realizamos muestreos con bultos en afloramientos fosilíferos en las penínsulas de Burica y Nicoya. Las condiciones paleoecológicas y paleoambientales fueron reconstruidas a partir de la comparación entre la estructura de las comunidades fósiles, con las comunidades modernas dragadas de los mares de Panamá, usando análisis de componentes principales. Los resultados indican que antes del cierre del Istmo, existieron islas oceánicas y un afloramiento moderado en Burica. Posterior al cierre, el choque de la DAC provocó la elevación del fondo marino y las aguas que se encontraban a 2 300m pasaron a 40m. El afloramiento se intensificaba en mar abierto pero la dorsal había formado islas en Burica que limitaban el efecto del afloramiento en la costa. La subducción de la DAC continuó y las islas se unieron gradualmente a tierra firme y desaparecieron, permitiendo el afloramiento. Durante el Pleistoceno medio un segundo proceso de levantamiento acelerado continuó elevando el fondo marino y formó la Cordillera de Talamanca. La cordillera creó una barrera que bloqueó el paso de los vientos Alisios y originó condiciones ecológicas y optimas que permiten el crecimiento de los mejores arrecifes de coral costeros del Pacífico oriental tropical (POT) entre Panamá y Costa Rica.


Asunto(s)
Ambiente , Fósiles , Océanos y Mares , Costa Rica , Geografía , Panamá
16.
Rev Biol Trop ; 60(2): 893-908, 2012 Jun.
Artículo en Español | MEDLINE | ID: mdl-23894954

RESUMEN

The evolution of the marine communities along the Pacific coast of Central America, may have changed in response to the formation of the Isthmus of Panama. To evaluate the effect of the Aseismic Cocos Ridge (DAC) subduction on the marine benthic communities, we reconstructed benthic assemblages from Neogene fossiliferous formations in Burica and Nicoya peninsulas of Panama and Costa Rica. Paleoecological and paleoenvironmental conditions were reconstructed by comparing community structure from bulk fossil samples with dredge collections from modern Tropical American seas, using principal component analysis. Our results indicate that during the early Pliocene, before the closing of the Isthmus, some oceanic islands existed with moderate upwelling in the Burica region. After the closure, during the late Pliocene and early Pleistocene the collision of the DAC caused an uplift of the seafloor, where water depth of 2 300m became shallow waters of less than 40m depth. Meanwhile, upwelling intensified in the open ocean the uplift that had formed small islands in coastal areas of Burica, creating protected areas and limiting the upwelling effect that was given in open ocean. The subduction of the DAC continued until the islands were joined to the mainland and gradually disappeared, allowing the return of the upwelling. During the middle Pleistocene a second process of accelerated uplift with speeds of 8m/1000 years provoked again the elevation of the seafloor and later the elevation of the Talamanca Range. The new range formed a barrier that blocked the passage of the Trade winds, created new ecological conditions and optimized and allowed the growth of the best coral reefs in the coasts of the tropical Eastern Pacific (POT) between Panama and Costa Rica.


Asunto(s)
Ambiente , Fósiles , Océanos y Mares , Costa Rica , Geografía , Panamá
17.
Exp Appl Acarol ; 52(4): 327-42, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20512613

RESUMEN

A user-friendly method to deliver Metarhizium spores to honey bee colonies for control of Varroa mites was developed and tested. Patty blend formulations protected the fungal spores at brood nest temperatures and served as an improved delivery system of the fungus to bee hives. Field trials conducted in 2006 in Texas using freshly harvested spores indicated that patty blend formulations of 10 g of conidia per hive (applied twice) significantly reduced the numbers of mites per adult bee, mites in sealed brood cells, and residual mites at the end of the 47-day experimental period. Colony development in terms of adult bee populations and brood production also improved. Field trials conducted in 2007 in Florida using less virulent spores produced mixed results. Patty blends of 10 g of conidia per hive (applied twice) were less successful in significantly reducing the number of mites per adult bee. However, hive survivorship and colony strength were improved, and the numbers of residual mites were significantly reduced at the end of the 42-day experimental period. The overall results from 2003 to 2008 field trials indicated that it was critical to have fungal spores with good germination, pathogenicity and virulence. We determined that fungal spores (1 × 10(10) viable spores per gram) with 98% germination and high pathogenicity (95% mite mortality at day 7) provided successful control of mite populations in established honey bee colonies at 10 g of conidia per hive (applied twice). Overall, microbial control of Varroa mite with M. anisopliae is feasible and could be a useful component of an integrated pest management program.


Asunto(s)
Abejas/parasitología , Metarhizium , Control Biológico de Vectores/métodos , Varroidae , Animales , Abejas/microbiología , Esporas Fúngicas/patogenicidad , Esporas Fúngicas/fisiología , Temperatura , Virulencia
18.
Am Surg ; 73(10): 955-8, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17983055

RESUMEN

No standardized approach exists for laparoscopic Roux-en-Y gastric bypass (LRYGB). At a newly instituted bariatric surgery program, four experienced laparoscopic surgeons used the systematic and evidence-based approach consisting of multidisciplinary preoperative evaluation, screening, and education; standardized operative technique; inpatient clinical pathway; and close postoperative follow-up. The outcomes were subsequently analyzed to determine if this approach improved the morbidity and mortality. From January 2003 to June 2006, 835 consecutive LRYGBs were performed. The patient population was 85 per cent women with a mean body mass index (BMI) of 50.4 kg/m2 (range 33-96 kg/m2). The mean age was 44 (range 15-67). Sixty-two per cent of the patients had previous abdominal or pelvic operations. The conversion rate to open surgery was 0.2 per cent. The average length of hospital stay was 2.6 days (range 2-13 days). There were no anastomotic leaks or deaths. The 30-day readmission and re-operation rates were 3.2 per cent and 1.8 per cent, respectively. The incidence of anastomotic stricture, marginal ulcer, bleeding, pulmonary embolism, and internal hernia was 0.8 per cent, 3.5 per cent, 4.2 per cent, 0.1 per cent, and 0.4 per cent, respectively. A systematic and evidence-based approach to the LRYGB by experienced laparoscopic surgeons resulted in a lower incidence of complications when compared with the published results from other comparable institutions.


Asunto(s)
Derivación Gástrica , Adolescente , Adulto , Anciano , Comorbilidad , Vías Clínicas , Medicina Basada en la Evidencia , Femenino , Derivación Gástrica/métodos , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Obesidad Mórbida/epidemiología , Obesidad Mórbida/cirugía , Resultado del Tratamiento
19.
Am Surg ; 72(10): 857-61, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17058721

RESUMEN

In the bariatric surgery literature, the optimum approach to the gallbladder is controversial. Recommendations range from concomitant cholecystectomy to selective screening and postoperative medical prophylaxis. At our institution, we have taken a highly selective approach where patients are not routinely screened for gallstones, nor are they medically treated postoperatively with bile salts. We have reviewed our experience with this approach. From January 2003 to January 2005, 407 laparoscopic Roux en Y gastric bypasses were performed at UCLA and postoperative outcomes were collected into a prospective database. Exclusion criteria included previous cholecystectomy, a follow-up period less than 6 months, or incomplete records. One hundred ninety-nine patients were included in the study. With a mean follow up period of 17.8 months, 12 (6%) patients required cholecystectomy for gallstone-induced pathology. Laparoscopic removal was performed in 11 (92%) patients. Indications for surgery included acute cholecystitis in five (2.5%) patients, gallstone pancreatitis in two (1%) patients, and biliary colic alone in another five (2.5%) patients. The incidence of symptomatic gallstones requiring cholecystectomy after laparoscopic Roux en Y gastric bypass is low. These results are similar to those from institutions where routine preoperative screening and prophylactic postoperative medical therapy is used. Routine preoperative screening or medical prophylaxis may not be necessary.


Asunto(s)
Anastomosis en-Y de Roux/métodos , Ácidos y Sales Biliares/uso terapéutico , Colecistolitiasis/diagnóstico , Derivación Gástrica/métodos , Laparoscopía , Adulto , Anciano , Enfermedades de las Vías Biliares/cirugía , Quimioprevención , Colecistectomía Laparoscópica , Colecistitis/cirugía , Colecistolitiasis/prevención & control , Colecistolitiasis/cirugía , Cólico/cirugía , Femenino , Estudios de Seguimiento , Humanos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Pancreatitis/cirugía , Cuidados Posoperatorios , Cuidados Preoperatorios , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento
20.
Am Surg ; 72(10): 862-4, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17058722

RESUMEN

Routine early postoperative upper gastroesophageal imaging (UGI) is often used in laparoscopic Roux-en-Y gastric bypass (LRYGB) procedures to confirm anastomotic patency and to exclude leaks. The aim of our study was to assess the usefulness of this practice. From January 2003 to November 2004, 322 LRYGB cases were performed using linear staplers for the gastrojejunostomy and jejuno-jejunostomy anastomoses. As part of our protocol, all patients received a Gastrograffin (Mallinkrodt, Inc., St Louis, Missouri) UGI on postoperative Day 1. The same radiological techniques were used and the same radiological team reviewed all films. Abnormal films were identified. In addition, patient demographics, time to discharge, and complications were collected and analyzed in a prospective database. There were no anastomotic leaks or obstructions. However, 42 of 322 (13%) studies demonstrated delayed gastric emptying. There were no statistically significant differences between patients with normal and delayed UGI studies. Routine UGI studies did not contribute significantly to patient care, and its routine use was subsequently abandoned.


Asunto(s)
Anastomosis en-Y de Roux/métodos , Esófago/diagnóstico por imagen , Derivación Gástrica/métodos , Laparoscopía , Estómago/diagnóstico por imagen , Adulto , Anastomosis en-Y de Roux/efectos adversos , Anastomosis en-Y de Roux/instrumentación , Medios de Contraste , Diatrizoato de Meglumina , Femenino , Estudios de Seguimiento , Derivación Gástrica/efectos adversos , Vaciamiento Gástrico/fisiología , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Tiempo de Internación , Masculino , Alta del Paciente , Cuidados Posoperatorios , Complicaciones Posoperatorias , Estudios Prospectivos , Radiografía , Engrapadoras Quirúrgicas/efectos adversos
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