The last glacial termination on the eastern flank of the central Patagonian Andes (47ºS)

Few studies have examined in detail the sequence of events during the last glacial termination (T1) in the core sector of the Patagonian Ice Sheet (PIS), the largest ice mass in the Southern Hemisphere outside of Antarctica. Here we report results from Lago Edita (47°8′ S, 72°25′ W, 570 m a.s.l.), a small closed-basin lake located in a valley overridden by eastward-flowing Andean glaciers during the Last Glacial Maximum (LGM). The Lago Edita record shows glaciolacustrine sedimentation until 19 400 yr BP, followed by organic sedimentation in a closed-basin lake and a mosaic of cold-resistant hygrophilous conifers and rainforest trees, along with alpine herbs between 19 400 and 11 000 yr BP. Our data suggest that the PIS retreated at least  ∼  90 km from its LGM limit between  ∼  21 000 and 19 400 yr BP and that scattered, low-density populations of cold-resistant hygrophilous conifers, rainforest trees, high-Andean and steppe herbs thrived east of the Andes during the LGM and T1, implying high precipitation levels and southern westerly wind (SWW) influence at 47° S. The conifer Podocarpus nubigena increased between 14 500 and 13 000 yr BP, suggesting even stronger SWW influence during the Antarctic Cold Reversal, after which it declined and persisted until 11 000 yr BP. Large increases in arboreal pollen at  ∼  13 000 and  ∼  11 000 yr BP led to the establishment of forests near Lago Edita between 10 000 and 9000 yr BP, suggesting a rise in the regional tree line along the eastern Andean slopes driven by warming pulses at  ∼  13 000 and  ∼  11 000 yr BP and a subsequent decline in SWW influence at  ∼  11 000 yr BP. We propose that the PIS imposed a regional cooling signal along its eastern, downwind margin through T1 that lasted until the separation of the northern and southern Patagonian ice fields along the Andes during the Younger Dryas period. We posit that the withdrawal of glacial and associated glaciolacustrine environments through T1 provided a route for the dispersal of hygrophilous trees and herbs from the eastern flank of the central Patagonian Andes, contributing to the afforestation of the western Andean slopes and pacific coasts of central Patagonia during T1.Fil: Henríquez, William I.. Victoria University Of Wellington; Nueva ZelandaFil: Villa-Martinez, Rodrigo. Gaia-antártica Universidad de Magallanes; ChileFil: Vilanova, Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; ArgentinaFil: De Pol-Holz, Ricardo. Gaia-antártica Universidad de Magallanes; ChileFil: Moreno, Patricio. Instituto de Ecología y Biodiversidad, Departamento de; Chil

Bilateral laparoscopic synchronous adrenalectomy in bilateral pheochromocytoma: experience in 8 patients

Indexación: Web of Science; ScieloAim: To evaluate 8 cases of bilateral pheochromocytoma and laparoscopic synchronous treatment. Patients and Methods: From May 1999 to May 2010, 8 patients with bilateral pheochromocytoma were found. A complete preoperative workup was done. Results: We perform 8 transperitoneal laparoscopic bilateral synchronous adrenalectomy. There was no open converted procedure. Mean operative time was 184.37 min. (range 95 to 300 min). Mean hospital stay was 3.8 days (range 3 to 5 days). Mean blood loss was 191.25 ml (range 0 to 500 min). In 7 cases the histopathological result was of pheochromocytoma and 1 as a malignant pheochomocytoma based on its histology. Conclusions: With very well establish diagnostic disease, an appropriate anesthetic strategy and as surgical skills, laparoscopic bilateral synchronic adrenalectomy is a feasible and safe surgical technique for bilateral pheochromocytomas.Introducción: La incidencia del feocromocitoma varía entre un 0,005 y un 0,1% y de estos sólo un 10% se presenta en forma bilateral. El objetivo de este trabajo es presentar nuestra experiencia en adrenalectomía laparoscópica bilateral sincrónica en pacientes con diagnóstico de feocromocitoma bilateral. Se revisa la literatura y se analizan nuestros resultados. Material y Métodos: Se realiza una revisión retrospectiva de todos los pacientes sometidos a una adrenelectomía laparoscópica bilateral sincrónica entre mayo de 1999 y mayo de 2010, con diagnóstico de un feocromocitoma bilateral. Todos los pacientes fueron estudiados con medición de catecolaminas plasmáticas y urinarias y estudio por imágenes. Resultados: Se realizaron 8 adrenelectomías laparoscópicas bilaterales sincrónicas. El tiempo promedio de cirugía fue de 184 min (rango 95-300 min). La estadía intrahospitalaria media fue de 3,8 días (rango de 3-5 días). El promedio de sangrado fue de 83 ml (rango 0-500 ml). El diagnóstico histopatológico fue de feocromocitoma en todas las muestras, en un caso se diagnosticó un feocromocitoma maligno. No hubo conversión a cirugía abierta. Conclusiones: La adrene-lectomía laparoscópica bilateral sincrónica para feocromocitomas bilaterales es un procedimiento seguro y de baja morbilidad, realizada por un cirujano con experiencia en cirugía laparoscópica. Es necesario tener previamente el diagnóstico de certeza para el manejo anestésico y postquirúrgico adecuado para estos pacientes.http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-40262011000600005&nrm=is

Publicaciones médicas: ¿ciencia o negocio?

En los últimos años ha aumentado enormemente el número de revistas científicas, de tal manera que hoy día es imposible leer ni siquiera el 1% de lo que se publica sobre nuestra especialidad o sobre los campos que nos interesen. La proliferación de revistas científicas en general y en el campo de la Medicina en especial puede ser debido a muchas razones. Entre ellas destacan, en nuestra opinión, la aparición de Internet y el cambio de la razón de ser de las publicaciones científicas. Comentaremos en esta revisión las razones que han llevado a este hecho.Sociedad Canaria de Osteoporosis (2016)

Effectiveness of disinfectant treatments for inactivating Piscirickettsia salmonis

This short communication investigated in vitro differences between commercial disinfectants types (n = 36), doses of application, and time of action in the elimination of Piscirickettsia salmonis, the most important bacterium affecting farmed salmon in Chile. Seven different treatments were examined, including active and inactive chlorine dioxides, glutaraldehyde, hypochlorite disinfectants and detergents, peracetic acid, peroxides and other miscellaneous methods A 3 replicate set of each of the sample groups was stored at 20 °C and 95% relative humidity and retested after 1, 5 and 30 min with varying doses (low, recommended and high doses). Multiple comparison tests were performed for the mean log CFU/ml among different disinfectant types, dose (ppm) and time of exposure (minutes) on the reduction of P. salmonis. Overall, disinfection using peracetic acid, peroxides, and both active and inactive chlorine dioxides caused significantly higher reduction of >7.5 log CFU/ml in samples, compared to other tested sanitizers. The lowest reduction was obtained after disinfection with hypochlorite detergents. As expected, as doses and time of action increase, there was a significant reduction of the overall counts of P. salmonis. However, at lowest doses, only use of paracetic acids resulted in zero counts. Implementation of effective protocols, making use of adequate disinfectants, may enhance biosecurity, and ultimately, mitigate the impact of P. salmonis in farmed salmon

Reemplazo ureteral con apéndice cecal

Indexación: Web of Science; ScieloWe report two cases with ureteral lesions. A 34 years male with a residual retroperitoneal mass caused by a testicular cancer, that persisted after chemotherapy. During the surgical excision of the mass, the involvement of the right ureter was discovered. A 43 years old female with a left ureteral lesion secondary to radiation therapy and with a non-functioning contralateral kidney. In both cases a ureteral replacement with the cecal appendix was performed, without surgical complications. After five years of follow up, the urinary tract of the male patient is normal. The female patient required an endoscopic incision of the connection between the appendix and the urinary bladder, eight years after the surgical procedure. Three years after the endoscopic procedure the repaired urinary tract is in good conditions.Objetivo: Presentar dos casos de reemplazo ureteral con apéndice cecal y revisar la literatura relacionada al tema. Material y Método: Presentamos dos casos de lesión ureteral. Un paciente de 34 años con masa retroperitoneal residual post quimioterapia englobando el uréter derecho, secundaria a un tumor testicular, y una paciente de 43 años monorrena funcional con lesión ureteral izquierda actínica. Resultados: En ambos casos se realizó un reemplazo ureteral, derecho e izquierdo, sin complicaciones intraoperatorias. El seguimiento alejado a 5 y 11 años muestra indemnidad de la vía urinaria. Conclusión: Estos 2 casos, con seguimiento prolongado, apoyan la factibilidad del uso del apéndice cecal como variante para el reemplazo ureteral en lesiones extensas.http://ref.scielo.org/n85xn

Effect of zinc intake on growth in infants: A meta-analysis

A systematic review and meta-analysis of available randomized controlled trials (RCTs) was conducted to evaluate the effect of zinc (Zn) intake on growth in infants. Out of 5500 studies identified through electronic searches and reference lists, 19 RCTs were selected after applying the exclusion/inclusion criteria. The influence of Zn intake on growth was considered in the overall meta-analysis. Other variables were also taken into account as possible effect modifiers: doses of Zn intake, intervention duration, nutritional status, and risk of bias. From each select growth study, final measures of weight, length, mid upper arm circumference (MUAC), head circumference, weight for age z-score (WAZ), length for age z-score (LAZ), and weight for length z-score (WLZ) were assessed. Pooled β and 95% confidence interval (CI) were calculated. Additionally, we carried out a sensitivity analysis. Zn intake was not associated with weight, length, MUAC, head circumference, and LAZ in the pooled analyses. However, Zn intake had a positive and statistically effect on WAZ (β = 0.06; 95%CI 0.02 to 0.10) and WLZ (β = 0.05; 95%CI 0.01 to 0.08). The dose–response relationship between Zn intake and these parameters indicated that a doubling of Zn intake increased WAZ and WLZ by approximately 4%. Substantial heterogeneity was present only in length analyses (I2 = 45%; p = 0.03). Zn intake was positively associated with length values at short time (four to 20 weeks) (β = 0.01; CI 95% 0 to 0.02) and at medium doses of Zn (4.1 to 8 mg/day) (β = 0.003; CI 95% 0 to 0.01). Nevertheless, the effect magnitude was small. Our results indicate that Zn intake increases growth parameters of infants. Nonetheless, interpretation of these results should be carefully considered

Análisis semicuantitativo del calcio y fósforo en los tejidos calcificados de la mandíbula

El objetivo de nuestra investigación es realizar un estudio microanalítico semicuantitativo del calcio y el fósforo en los tejidos calcificados de la mandíbula. Dentro de este estudio se pretende calcular el valor de la ratio Ca/P por métodos semicuantitativos y compararlo con los valores estequiométricos de la ratio Ca/P de la hidroxiapatita referidos en la literatura; conocer los valores de la ratio Ca/P obtenidos para el tejido condroide, el hueso lamelar, el hueso fibrorreticular y el cartílago calcificado en las muestras fetales, por una parte, y adultas, por otra; y si existen o no diferencias significativas en la proporción Ca/P obtenidos para feto y adulto. El análisis morfológico de los tejidos calcificados fue realizado por medio de Microrradiografía Electrónica de Barrido (MEB) por electrones retrodispersados (Backscattering), y los resultados permiten afirmar que la ratio obtenida por análisis semicuantitativo mediante dispersión de rayos X de los tejidos calcificados (condroide, hueso lamelar y fibrorreticular) se encuentra más próxima a 1, y que no existen diferencias significativas entre las muestras fetales y de adulto en los tejidos analizados

Primer registro de Litomosoides pardinasi (Nematoda: Onchocercidae) en roedores nativos y exóticos de Chile

We report the first record of Litomosoides pardinasi in native and exotic rodents from Chile. Litomosoides pardinasi, described in the Argentine Patagonia parasitizing Phyllotis xanthopygus and Oligoryzomys longicaudatus, was found in Chile parasitizing the peritoneal and thoracic cavities of O. longicaudatus (prevalence (P)= 18.9%, mean intensity (MI)= 57.3) and Phyllotis darwini (P= 4.2%, MI= 10), and in the peritoneal cavity of Rattus rattus (P= 1.24%; MI= 22.5). Total P in native rodents from Chile was significantly lower than in Argentina, while the total MI was higher. Prevalence and MI of L. pardinasi in O. longicaudatus from Chile and Argentina showed non-significant differences; prevalence in P. darwini from Chile was significantly lower than in P. xanthopygus from Argentina and than in Chilean O. longicaudatus. Our results, together with those from Argentina, support the hypothesis that L. pardinasi is well established in O. longicaudatus, but seems to be recently acquired by P. darwini and the exotic R. rattus. Considering the known host distribution of Litomosoides species among the sigmodontines, our results also support the hypothesis that L. pardinasi first colonized the Oryzomyini tribe and later, by different phenomena of host-switching, colonized the Phyllotini tribe and the exotic R. rattus.Litomosoides pardinasi es registrada por primera vez en roedores nativos y exóticos de Chile. La especie Litomosoides pardinasi, parásita de Phyllotis xanthopygus y Oligoryzomys longicaudatus en la Patagonia Argentina, fue encontrada en Chile parasitando la cavidad torácica y abdominal de O. longicaudatus (prevalencia (P)= 18.9%, intensidad media (MI)= 57.3) y de Phyllotis darwini (P= 4.2%, MI= 10), y la cavidad abdominal del roedor exótico Rattus rattus (P= 1.24%; MI= 22.5). La P total en roedores nativos de Chile fue significativamente menor que la P de Argentina, en tanto la MI total fue significativamente mayor. La P y MI de L. pardinasi en O. longicaudatus de Chile y Argentina no mostraron diferencias significativas; la P en P. darwini de Chile fue significativamente menor que la de P. xanthopygus de Argentina y que la de O. longicaudatus de Chile. Considerando la distribución de las especies de Litomosoides entre los sigmodontinos, estos resultados apoyan la hipótesis que L. pardinasi está bien establecida en O. longicaudatus y que posiblemente haya sido recientemente adquirida por P. darwini y R. rattus. Así, L. pardinasi colonizó primero a la Tribu Oryzomyini y posteriormente por un fenómeno de cambio de hospedero a la Tribu Phyllotini y a R. rattus.Facultad de Ciencias Naturales y Muse