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Ongoing climate change threatens the biodiversity of glacier-fed river ecosystems worldwide through shifts in water availability and timing, temperature, chemistry, and channel stability. However, tropical glacier-fed rivers have received little attention compared to those in temperate and Arctic biomes, despite their unique biodiversity potentially responding differently due to additional stress from higher altitude locations thus lower oxygen availability, diurnal freeze-thaw cycles, and annual monsoon rainfall disturbances. However, tropical glacier-fed rivers have received little attention compared to those in temperate and Arctic biomes, despite their unique biodiversity potentially responding differently due to additional stress from higher altitude locations thus lower oxygen availability, diurnal freeze-thaw cycles, and annual monsoon rainfall disturbances. This study quantified aquatic biodiversity responses to decreasing glacier cover in the Cordillera Blanca range of the Peruvian Andes. Ten rivers were studied along a gradient of decreasing glacier cover in the Parón, Huaytapallana, and Llanganuco basins, with a specific focus on macroinvertebrates and physicochemical parameters in both the dry and wet seasons. We found higher temperatures, more stable and lower turbidity rivers as glacier cover decreased, which were related significantly to higher local diversity and lower ß-diversity. Analysis of similarity revealed significant differences in the macroinvertebrate community among rivers with high, medium, or low glacier cover, illustrating turnover from specialists to generalists as glacial influence decreased. Redundancy analysis demonstrated that there were more species found to prefer stable beds and water temperatures in medium and low glacier cover in a catchment rivers. However, certain taxa in groups such as Paraheptagyia, Orthocladiinae, Anomalocosmoecus, and Limonia may be adapted to high glacial influence habitats and at risk of glacier retreat. Although species composition was different to other biomes, the Cordillera Blanca rivers showed similar benthic macroinvertebrate biodiversity responses to glacier retreat, supporting the hypothesis that climate change will have predictable effects on aquatic biodiversity in mountain ranges worldwide.

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BACKGROUND: Planning surgical procedures of the lower leg benefits from considering the possibility of an aberrant anterior tibial artery (AATA), but previously published data on the frequency of this anatomic variant shows heterogeneity. We assessed the prevalence of AATA in a Latin American cohort using magnetic resonance imaging (MRI) and compared these with other studies reported in the literature. METHODS: We retrospectively included consecutive patients who had undergone multiplanar knee MRI at a radiology department in Lima, Peru. The MRI protocol included coronal T1 weighted, axial, sagittal and coronal proton density fat-saturated (PDFS) and sagittal T2 weighted images. Two experienced radiologists assessed all images and were blinded to each other's findings. The frequency of the AATA was compared to previous cohorts. A scoping review was undertaken to provide an overview of previously published data on the prevalence of ATAA. RESULTS: We analyzed 280 knee MRI examinations of 253 patients (median age 41 years (IQR 31-52), 53.8% male). The aberrant anterior tibial artery variant was present in 8 of 280 (2.9%) evaluated knees, resulting in a prevalence of 3.2% in our study population. The PDFS sequence in the axial or sagittal orientation was most effective to identify AATA. The frequency of AATA in the reviewed literature using different radiological modalities ranged from 0.4 to 6% (median 1%, IQR (0.5-2.3%). CONCLUSIONS: The AATA is a frequent vascular variant that can be detected by MRI in the preparation of invasive interventions of the lower leg.

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BACKGROUND: Among patients with coronary artery disease (CAD), 80%-90% present at least one conventional risk factor. On the other hand, lipid profile modification after a cardiovascular event related to acute coronary syndrome (ACS) has been recognized. The prevalence of conventional risk factors and the lipid profile at the time of admission in patients with ACS and significant CAD (stenosis ≥50%) determined through coronary angiography is not well described. METHODS: We studied 3,447 patients with a diagnosis of ACS and significant CAD with stenosis ≥50%, as shown o n angiography. We recorded the presence of conventional risk factors, including smoking, hypertension, dyslipidemia, and diabetes. In addition, we analyzed the lipid profiles within the first 24 hours of admission. We analyzed the studied population and compared findings according to sex. RESULTS: Most patients (81.7%) were male. ST-elevation myocardial infarction was present in 51.3% of patients, and non-ST-elevation acute coronary syndrome was present in 48.7%. The most frequent risk factor was smoking, which was present in 68% of patients, followed by hypertension (57.8%), dyslipidemia (47.5%), and diabetes (37.7%). In women, the most frequent risk factors were hypertension, diabetes, and dyslipidemia, whereas in men, smoking was the most frequent. We identified at least one risk factor in 95.7% of all patients, two or three risk factors in 62%, and four risk factors in 8.6% of patients. The lipid profile analysis revealed that 85.1% of patients had some type of dyslipidemia, and the most frequent was low levels of high-density lipoprotein cholesterol (68.6% of cases). CONCLUSION: We found at least one conventional risk factor in 95.7% of patients with ACS and significant CAD. The lipid profile analysis revealed that two thirds of cases had low high-density lipoprotein cholesterol levels.

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Mercury (Hg) is a toxic metal that is transported globally through the atmosphere. The emission of Hg from mineral reservoirs and subsequent recycling in surface reservoirs (i.e., soil/biomass, ocean, and atmosphere) are fundamental to the modern global Hg cycle, yet past emissions from anthropogenic and natural sources are not fully constrained. We use a sediment core from Yanacocha, a headwater lake in southeastern Peru, to study the anthropogenic and natural controls on atmospheric Hg deposition during the Holocene. From 12.3 to 3.5 ka, Hg fluxes in the record are relatively constant (mean ± 1σ: 1.4 ± 0.6 µg m-2 a-1, n = 189). Past Hg deposition does not correlate with changes in regional temperature and precipitation, inferred from nearby paleoclimate records, or with most large volcanic events that occurred regionally, in the Andean Central Volcanic Zone (~300-400 km from Yanacocha), and globally. In B.C. 1450 (3.4 ka), Hg fluxes abruptly increased and reached the Holocene-maximum flux (6.7 µg m-2 a-1) in B.C. 1200, concurrent with a ~100-year peak in Fe and chalcophile metals (As, Ag, Tl) and the presence of framboidal pyrite. Continuously elevated Hg fluxes from B.C. 1200-500 suggest a protracted mining-dust source near Yanacocha that is identical in timing to documented pre-Incan cinnabar mining in central Peru. During Incan and Colonial time (A.D. 1450-1650), Hg deposition remains elevated relative to background levels but lower relative to other Hg records from sediment cores in central Peru, indicating a limited spatial extent of preindustrial Hg emissions. Hg fluxes from A.D. 1980 to 2011 (4.0 ± 1.0 µg m-2 a-1, n = 5) are 3.0 ± 1.5 times greater than pre-anthropogenic fluxes and are similar to modern fluxes documented in remote lakes around the world.

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Introducción: Se incluyen 55 pacientes con el diagnóstico de hepatocarcinoma para determinar los factores asociados a mortalidad. Método: Se realizó un estudio de tipo descriptivo, retrospectivo y corte transversal, mediante la revisión documental de historias clínicas del Hospital Nacional del Sur Carlos Alberto Seguín Escobedo EsSalud entre los años 2000 a 2004. Resultados: Se encontró que de los 55 pacientes fallecieron el 47.27 por ciento, con una predominancia para el sexo masculino 69.29 por ciento, y en edades entre los 60 y 80 años. Los factores de riesgo asociados a diagnóstico de hepatocarcinoma incluyeron principalmente el antecedente de consumo de alcohol, de anticonceptivos orales en mujeres, el de paracetamol, en general, y en menor porcentaje por infección crónica por virus hepatotrofos. Conclusiones: El hepatocarcinoma afectó más a varones (69,09 por ciento) que a mujeres (30,91 por ciento), diferencia que resulta ser estadísticamente significativa (p menor que 0,01). La edad de afectación fue bastante variable, alcanzando a niños de 2 años y hasta ancianos de 93 años. El síntoma principal es dolor en hipocondrio derecho. Al examen físico masa palpable en cuadrante superior derecho 52.72 por ciento.

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INTRODUCTION: The cystic tumor of the pancreas is a relatively uncommon entity. There are different types of pancreatic cystic tumors and they all exhibit different degrees of malignancy. These tumors represent 1% of all primary pancreatic tumors and only 15% of the cystic lesions. The serous cystadenomas (SCA) are mostly benign lesions with an average size of 4 cm; nevertheless, in some rare cases these are giant lesions, generally larger than 15 cm. Sometimes these tumors produce a symptomatology caused by the compression of neighboring structures, therefore they are generally operable. MATERIAL AND METHOD: During the period from June 2004 to June 2005, the 3A II unit of the Edgardo Rebagliati Martins Hospital operated on two cases of giant serous cystadenomas of the pancreas, one located in the tail of the pancreas and the other in the head of the pancreas, with an average size of 16 cm. DISCUSSION: The giant SCAs of the pancreas are rarely seen lesions that, according to different authors, are usually larger than 10 to 15 cm. in diameter. These lesions do not represent a diagnosis problem and are generally operable since they produce a symptomatology by compression. The surgical resection can be complicated due to their large size and to the considerable neovascularization.

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Introducción: Los tumores quísticos del páncreas son una entidad poco común que reúnen a distintas variedades. Las cuales presentan diferentes grados de malignidad. Estos representan el 1 por ciento de todos los tumores primarios del páncreas y solo el 15 por ciento de las lesiones quísticas. Los cistoadenomas serosos (SCA) son lesiones casi siempre benignas con un tamaño promedio de 4 cm sin embargo en muy raros casos existen lesiones gigantes generalmente mayores de 15 cm, estos tumores algunas veces producen una sintomatología causada por la comprensión de estructuras vecinas por lo que generalmente son quirúrgicos. Material y método: Durante el periodo comprendido entre Junio del 2004 a Junio del 2005 se operaron en el servicio 3A II del Hospital Edgardo Rebagliati Martins dos casos de cistoadenomas serosos gigantes del páncreas uno localizado en la cola del páncreas y otro en la cabeza con un tamaño promedio de 16 cm. Discusión: Los SCA gigantes del páncreas son lesiones muy poco frecuentes generalmente mayores de 10 a 15 cm. de diámetro de acuerdo a los diferentes autores, estas lesiones no presentan un problema diagnóstico, siendo generalmente quirúrgicas ya que producen sintomatología por comprensión. La resección quirúrgica puede ser complicada debido al gran tamaño y a la neovascularización importante que presentan.

Introduction: The cystic tumor of the pancreas is a relatively uncommon entity. There are different types of pancreatic cystic tumors and they all exhibit different degrees of malignancy.These tumors represent 1 per cent of all primary pancreatic tumors and only 15 per cent of the cystic lesions. The serous cystadenomas (SCA) are mostly benign lesions with an average size of 4 cm; nevertheless, in some rare cases these are giant lesions, generally larger than 15 cm. Sometimes these tumors produce a symptomatology caused by the compression of neighboring structures, therefore they are generally operable.MATERIAL AND METHOD: During the period from June 2004 to June 2005, the 3A II unit of the Edgardo RebagliatiMartins Hospital operated on two cases of giant serous cystadenomas of the pancreas, one located in the tail of the pancreas and the other in the head of the pancreas, with an average size of 16 cm. DISCUSSION: The giant SCAs of the pancreas are rarely seen lesions that, according to different authors, are usually larger than 10 to 15 cm. in diameter. These lesions do not representa diagnosis problem and are generally operable since they produce a symptomatology by compression. The surgical resection can be complicated due to their large size and to the considerable neovascularization.

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Presentamos el caso de un varón de 50 años con infarto agudo demiocardio sin factores comunes de riesgo coronario (Dislipidemia,Hipertensión, Síndrome Metabólico), con excepción del hábitota baquico. Que ingresó con un cuadro clínico, electrocardiográfico yenzimático de infarto agudo de miocardio. Se efectuó coronariografía con la intención de Angioplastía y/o Stent, y se encontraron lesiones coronarias mínimas. En consecuencia, solamente se indicó tratamiento médico. Se discuten los mecanismos del infarto en estepaciente...

A 50-year old man was evaluated in the cardiac clinic of the Instituto Nacional de Tórax, with myocardial infarction without common risk factors (like Dyslipidemia, Hypertension, Metabolic Syndrome), except the tobacco inhalation. He was admitted incardiac ward with the diagnosis of myocardial infarction by meansof electrocardiography, and enzimatic changes. After a few days acoronary angiography was performed with the objective of and stent implantation and there was found slight coronary lesions. There fore,he received only medical treatment. We discuss the pathophysiology of the myocardial infarction in this patient.

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El presente articulo pretende actualizar las indicaciones y las características técnicas básicas de los principales tipos de marcapasos, a propósito de la experiencia en el implante de los mismos. Con este fin se revisaron los expedientes de implantes de marcapasos elfectuados en el periodo Julio de 1996 a junio del 2003, en el Instituto Nacioal de Tórax. Se hace especial énfasis en la técnica quirúrgica. Las indicaciones más frecuentes para implante de marcapasos en la serie estudiada fueron la cardioesclerosis (61 porciento) y la cardiopatía chagásica (33 por ciento). La alteraión electrocardiográfica principal pre-implante fue el bloqueo auriculoventriclar completo /57 por ciento). La técnica habitual consistió en la disección venosa. La gran mayoría de los marcapsos implantados fueron del tipo VVI (86 por ciento). Los resultados son buenos con un mínimo índice de complicaciones.

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La investigación se realizó, utilizando las fuentes de información secundaria disponibles en los servicios pertinentes del departamento de cardiología del Instituto Nacional del Tórax. Se concideró que unestudio de estas características es necesario por que busca mejorar la demanda de servicios, facilitando en ecceso de las personas de bajos y medianos recursos que acuden al hospital público. La plena disponibilidad de la información aseguró la facilidad de la investigación. L a investigación es tracendente porque permitirá aplicar actividades gerenciales futuras, de sostenibilidad técnica y financiera para el acceso de los usuarios. Se trata también de un estudio de actualidad, considerando que la atención Médica gerenciada, es untema de discusión y de aplicación en América Latina por sus aplicaciones técnicas y sobre todo ideológicas.

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