Endocarditis infecciosa de válvula nativa: factores asociados a resultados adversos / Mortality predictors in patients with native valve infec tive endocarditis

Resumen Introducción : La mortalidad de la endocarditis infec ciosa (EI) en Argentina continúa siendo elevada. El obje tivo del trabajo fue describir las características clínicas e identificar factores asociados a mortalidad en pacientes con EI de válvula nativa. Métodos : Estudio de cohorte retrospectiva que inclu yó pacientes adultos con diagnóstico de EI de válvula nativa internados durante 2011-2021. Resultados : Se incluyeron 129 pacientes con una edad promedio de 66±17 años. El organismo responsa ble más frecuente (38.8%, n = 50) fue el Staphylococcus aureus (SA). El 63.6% presentó criterios de indicación quirúrgica. La mortalidad durante la internación fue del 22.5%. En el análisis multivariado que incluyó índice de comorbilidad Charlson, infección por SA y la presencia de criterios de indicación quirúrgica, se observó un OR ajustado de mortalidad de 1.32 (IC95% 1.10-1.57; p = 0.003), 2.75 (IC95% 1.11-6.8; p = 0.028) y 4.14 (IC95% 1.34-12; p = 0.013), respectivamente. En el análisis mul tivariado para mortalidad alejada que agregó el criterio quirúrgico y la realización de cirugía durante la inter nación, se observó un OR ajustado de 1.62 (IC95% 1.31- 2.00; p < 001), 0.77 (IC95% 0.31-1.93; p = 0.58), 7.49 (IC95% 2.07-27.07; p = 0.002) y 0.21 (IC95% 0.06-0.70; p = 0.01), respectivamente. Conclusiones : La mortalidad de la EI se asoció al grado de comorbilidad previa, a la forma de presenta ción y, en relación inversa, a la realización oportuna del tratamiento quirúrgico.

Abstract Introduction : Mortality of infective endocarditis (IE) in Argentina continues to be high. The aim objective was to describe the clinical characteristics and identify factors associated with in-hospital and long-term mortality in patients with native valve IE. Methods : Retrospective cohort study including adult patients with diagnosis of native valve IE, hospitalized during 2011-2021. Results : A total of 129 patients with a mean age of 66±17 years were included. The most frequent respon sible organism was Staphylococcus aureus (SA) (38.8%). Surgical indication criteria were present in 63.6% of the patients. Mortality during hospitalization was 22.5% .In the multivariate analysis that included Charlson comorbidity index, SA infection and the presence of surgical indication criteria, an adjusted OR of mor tality of 1.32 (95%CI 1.10-1.57; p = 0.003), 2.75 (95%CI 1.11-6.8; p = 0.028) and 4.14 (95%CI 1.34-12; p = 0.013), respectively, was observed. In the multivariate analysis for long term mortality, that added surgical indication criteria and the performance of surgery during hospitalization, an adjusted OR of 1.62 (CI95% 1.31-2.00; p<001), 0.77 (95%CI 0.31-1.93; p = 0.58), 7.49 (95%CI 2.07-27.07; p = 0.002) and 0.21 (95%CI 0.06-0.70; p = 0.01), respec tively, was observed. Conclusions : Mortality in IE was associated with the degree of previous comorbidity, with the presence of surgical indication criteria and, inversely, with the timely completion of surgical treatment.

Multi-criteria analysis applied to humanitarian assistance: an approach based on ELECTRE-MOr.

The recent increase in the number of cases of COVID-19 in Brazil and worldwide, caused by the Omicron Variant, has brought to light concern to the population and the government, especially in the states most affected by the pandemic. To find a way to help combat the pandemic, a case study was conducted to acquire new speedboats by the Brazilian Navy (BN), through the application of the ELECTRE-MOr multicriteria method. The boats would be employed as mobile hospitals, aiming to perform first aid and evacuation of patients from riverside regions to qualified hospitals. Another important use would be the transport of vaccines, medicines and basic supplies for riverside populations, such as water, food and hygiene materials. For the proposed analysis, we consulted three specialists from the BN, who evaluated eight boat models in seven tactical, operational and medical criteria. After the application of the method, the Guardian 25 and RAC boats were chosen to be employed in humanitarian assistance. This study brings a valuable contribution to academia and society since it represents the application of a multi-criteria decision-aid method in the state of the art to contribute to the solution of a real problem that affects millions of people in Brazil and worldwide.

Strategic support for the distribution of vaccines against Covid-19 to Brazilian remote areas: A multicriteria approach in the light of the ELECTRE-MOr method.

The pandemic caused by the new coronavirus has brought to light a series of concerns for the Brazilian population and government departments due to the different costly consequences that it has generated. It has also mobilized different strategic fronts that plan and implement several mitigating measures against the virus. Besides, the search for solutions for adequate care for individuals in need of support has been constant. This work uses ELECTRE-MOr, a Multi-Criteria Decision Aid (MCDA) method, to support the logistic plan for the vaccine distribution throughout Brazil, essentially to remote areas. The method allows an objective and structured classification of ideal types of thermal boxes for the storage of immunobiological inside the Cold Chain, presenting the best alternative that maintains the quality of materials until the final destination and has the best cost-benefit. Currently, the ELECTRE-MOr model is under development in a computational tool in Python, allowing the use of the method intuitively and clearly, enabling professionals of any area of expertise to apply it.

Tumor papilar sólido-quístico pancreático / Solid pseudopapillary tumor of the pancreas

RESUMEN Antecedentes: la neoplasia sólida pseudopapilar del páncreas es una entidad rara, que típicamente se presenta en mujeres jóvenes. Suele presentar síntomas abdominales inespecíficos. Es un tumor maligno de bajo grado de malignidad. Objetivos : el objetivo del siguiente informe de serie de casos es presentar 9 casos tratados en un cen tro y realizar una revisión bibliográfica del tema. Material y métodos: estudio retrospectivo descriptivo de los casos con diagnóstico anatomopatoló gico de neoplasia sólida pseudopapilar en el Servicio de Cirugía General, desde febrero de 2013 hasta septiembre de 2019. Se contemplaron como variables: edad, sexo, localización del tumor, tratamiento quirúrgico realizado, tiempo operatorio, complicaciones, estancia hospitalaria y seguimiento alejado. Resultados: fueron 9 casos, todos de sexo femenino con media de edad de 30 años (rango 20 a 70 años). La localización más frecuente fue en cola de páncreas en 4 casos (45%). Todas las pacientes fueron sometidas a cirugía, con abordaje laparoscópico en el 60% de los casos (n = 5); la resección pancreática distal con preservación esplénica fue la conducta más utilizada (n = 6). Se constataron tres complicaciones, de las cuales dos fueron colecciones abdominales como consecuencia de una fístula pancreática que se abordaron por vía percutánea, y la restante fue un retardo del vaciamiento gástrico por lo cual la paciente requirió internación prolongada. Conclusión: la neoplasia sólida pseudopapilar pancreática es una enfermedad poco frecuente, ma ligna pero con bajo riesgo de malignidad. Presenta buena sobrevida cuando se somete a cirugía de carácter curativo; la laparoscopia es la vía de abordaje de elección en centros con experiencia.

ABSTRACT Background: Solid pseudopapillary tumor of the pancreas is a rare condition that affects young women. The most common symptom is unspecific abdominal pain. It is a malignant tumor of low malignant potential. Objective: The aim of this study is to report a case series of patients treated in a single center and perform a bibliographic review. Material and methods: We conducted a retrospective study of the cases with pathological diagnosis of solid pseudopapillary tumor of the pancreas treated in the Department of General Surgery between February 2013 and September 2019. The following variables were analyzed; age, sex, tumor location, surgical treatment, operative time, complications, length of hospital stay and long-term follow-up. Results: Nine patients were included; all of them were women with mean age of 30 years (range: 20 - 70 years). The most common location of the tumor was the tail of the pancreas (n = 4; 45%). Surgery was performed in all the cases; five cases underwent video-assisted laparoscopy and spleen-preserving distal pancreatectomy was the technique more commonly used (n = 6). Three complications were recorded: two abdominal collections due to biliary leaks were trated by percutaneous approach and the other patient presented delayed gastric emptying and required prolonged hospitalization. Conclusion: Solid pseudopapillary tumor pf the pancreas is a rare low-grade malignant neoplasm. The prognosis is favorable after surgery and laparoscopy is the preferred approach in centers with experience.

La era de los microorganismos multirresistentes: impacto en pacientes neutropénicos febriles / he era of multidrug-resistant microorganisms: impact on febrile neutropenic patients

Introducción: El tratamiento antimicrobiano para los pacientes neutropénicos febriles (NF) se ha convertido en un desafío debido a la emergencia de microorganismos multirresistentes (MOR). El objetivo de este trabajo es analizar las características de estos pacientes y la incidencia de MOR. Materiales y métodos: Estudio retrospectivo, observacional y descriptivo desde junio de 2015 hasta agosto de 2017 en adultos neutropénicos febriles hospitalizados en un hospital público de la ciudad de Buenos Aires. Se analizaron características demográficas, clínicas y microbiológicas, incluyendo los siguientes MOR: enterobacterias productoras de carbapenemasas (EPC) y beta-lactamasas de espectro extendido (BLEE), Acinetobacter baumannii complex, Enterococcus vancomicina resistente (EVR) y Stenotrophomonas maltophilia. Resultados: Fueron incluidos 32 pacientes, 56% mujeres con 84% de neoplasias hematológicas. Hubo colonización por EPC o EVR en el 59% de los pacientes. Se registraron 148 episodios infecciosos con 41% de documentación microbiológica. Los MOR fueron responsables del 25% de los episodios, siendo los más frecuentes Klebsiella pneumoniae productora de carbapenemasa y BLEE; los focos más frecuentes fueron bacteriemias e infecciones urinarias. Los pacientes con leucemias agudas (67%) presentaron colonización por EPC o EVR en el 80%. El tratamiento fue inadecuado en el 63% de las infecciones RESUMENARTÍCULO ORIGINALpor MOR y en el 12% por microorganismos sensibles (MS) (p<0,01). La mortalidad global fue 53% con MOR y del 27% con MS (p=ns). Conclusión: las infecciones por MOR fueron frecuentes con predominio de bacteriemias, especialmente EPC y BLEE. Por ello los MOR deben ser tenidos en cuenta para el tratamiento empírico en pacientes neutropénicos febriles

Background: Antimicrobial treatment for febrile neutropenic (FN) patients has become a challenge due to the growing emergence of multidrug-resistant microorganisms (MDR-MO). The objective of this study was to analyze the characteristics of these population and the incidence of MDR-MO. Methods & Materials: Retrospective, observational and descriptive study from June 2015 to August 2017 in FN adults hospitalized at a public hospital in Buenos Aires city, Argentina. Demographic, clinical and microbiological characteristics were analyzed. We included the following MDR-MO: extended spectrum beta-lactamase (ESBL) and carbapenemase-producing Enterobacteriaceae (CPE), Acinetobacter baumannii complex, vancomycin resistant Enterococcus (VRE) and Stenotrophomonas maltophilia. Results: Thirty-two patients were included; 56% were women, with 84% haematological diseases. Colonization by CPE or VRE was observed in a 59% of the patients. There were 148 infectious episodes. Of them 41% had microbiological documentation. MDR-MO were responsible for 25% of the episodes and the most frequent were carbapenemase-producing Klebsiella pneumoniae and ESBL producing Enterobacteriaceae. MDR-MO were isolated mainly from bacteremia and urinary infections, patients had acute leukemia in a 67% and colonization CPKP or VRE in 80%. Inadequate treatment for MDR-MO was observed in 63% of the cases and 12% for susceptible microorganisms (p<0,01). The mortality was 53% for MDR-MO and 27% for susceptible microorganisms (p=ns). Conclusion: MDR-MO infections were frequent with predominance of bacteremia especially CPE and ESBL producing Enterobacteriaceae. According to these results MDR-MO should be taken into account for the empiric antimicrobial treatment in febrile neutropenic patients

[Trazodone in REM sleep behavior disorder]. / Trazodona en el trastorno del comportamiento del sueño MOR.

This case concerns an elderly man with a REM sleep behavior disorder, who was initially offered a pharmacological treatment with clonazepam, recommended by other articles, but with poor adherence due to its adverse reactions and persistence of symptoms. He was then offered a treatment with Trazodone was offered, achieving a complete remission of symptoms, with no reported side effects. It is clear that Trazodone has no known indication for this type of disorder; nevertheless, it was considered in this case because of its pharmacological profile, obtaining satisfactory results. Further research is needed in order to document thoroughly the mechanisms of action, efficacy and utility of this molecule in cases such as the one presented.

Trazodona en el trastorno del comportamiento del sueño MOR / Trazodone in REM sleep behavior disorder

A un varón adulto mayor, con un cuadro clínico documentado de trastorno comportamental del sueño MOR, inicialmente se le ofreció tratamiento farmacológico con clonazepam, recomendado por la literatura, pero se obtuvo mala adherencia por intolerancia a los efectos secundarios y la persistencia sintomática. Por ese motivo, se propuso el tratamiento con trazodona y se logró control sintomático completo, sin efectos adversos reportados por el paciente. Es claro que la trazodona no tiene indicación conocida para este tipo de trastornos, pero se consideró en este caso por su perfil farmacológico y se obtuvo un resultado clínico satisfactorio. Se plantea la necesidad de realizar mayores estudios que permitan documentar de manera suficiente la acción, la eficacia y la utilidad de esta molécula en casos como el ilustrado.

This case concerns an elderly man with a REM sleep behavior disorder, who was initially offered a pharmacological treatment with clonazepam, recommended by other articles, but with poor adherence due to its adverse reactions and persistence of symptoms. He was then offered a treatment with Trazodone was offered, achieving a complete remission of symptoms, with no reported side effects. It is clear that Trazodone has no known indication for this type of disorder; nevertheless, it was considered in this case because of its pharmacological profile, obtaining satisfactory results. Further research is needed in order to document thoroughly the mechanisms of action, efficacy and utility of this molecule in cases such as the one presented.

Fluctuating asymmetry in Apis mellifera(Hymenoptera: Apidae) as bioindicator of anthropogenic environments / Asimetría fluctuante en Apis mellifera (Hymenop-tera: Apidae) como bioindicador de ambientes antropo-génicos

The successful distribution of A. melliferais due to their ability to adjust to seasonal variations, considerable control over their internal physical environment and exploration of different resources. However, their populations have experienced different forms and levels of environmental pressure. This research aimed to verify the phenotypic plasticity in both size and shape of wings in A. melliferausing fluctuating asymmetry, based on geometric morphometrics from apiaries located in sites with high and low levels of anthropization. We sampled 16 locations throughout all five geographic regions of Brazil. At each site, samples were collected from 20 beehives installed in apiaries: 10 installed near high anthropogenic environments (Cassilàndia - MS, Fortaleza - CE, Maringá - PR, Aquidauana - MS, Rolim de Moura - RO, Riachuelo - SE, Ubirata - PR and Piracicaba - SP), and 10 in sites with low levels of human disturbance (Cassilàndia - MS, Itapiúna CE, Uniao da Vitoria - PR, Aquidauana - MS, Rolim de Moura - RO, Pacatuba - SE, Erval Seco - RS, Rio Claro - SP). A sample of 10 individuals was taken in each hive, totaling 200 per location, for a total of 1 600 individuals. We used fluctuating asymmetry (FA) in size and shape of the forewing through geometric morphometrics. The FA analysis was conducted in order to check bilateral differences. The indexes of size and shape were submitted to analysis of variance (ANOVA), where the characters evaluated were used as factors to verify the size and shape differences. The results indicated an asymmetry on the shape of the wing (P < 0.001) but no asymmetry was observed on wing size. Considering FA as an environmental response and high and low impacted areas as a fixed factor, we observed significant differences (P < 0.05). The results for the wing shape in A. melliferademonstrated that this feature undergoes more variation during ontogeny compared to the variation in size. We concluded that bee samples collected from colonies with higher levels of human disturbance had higher wing-shape asymmetry; the variation of fluctuating asymmetry in the wing shape of honeybees can be used as an indicator of the degree of environmental anthropization.

La distribución exitosa de A. melliferase debe a su capacidad para adaptarse a las variaciones estacionales, controlar considerablemente su ambiente físico interno y por la exploración de recursos. Sin embargo, sus poblaciones experimentan diferentes formas y niveles de presión ambiental. Esta investigación evaluó colmenares, ubicadas en entornos con distintos niveles de antropización. Ambientes considerados altamente antropogénicos fueron escogidos: áreas urbanas, agrícolas con aplicaciones de insecticidas, y las industrias con grandes áreas (regiones con altos índices de contaminación). Por otra parte, los entornos considerados con bajos niveles de perturbación humana fueron elegidos: áreas de preservación permanente de los bosques restantes (Mata Atlántica, Planalto, Cerrado), áreas ribereñas o reservas ecológicas. Se muestrearon 16 localidades que abarcan las cinco regiones del Brasil. Estamos utilizando la asimetría fluctuante desde el tamaño y la forma del ala anterior por técnicas de morfometría geométrica. En cada sitio, las muestras se obtuvieron de las 20 colmenas instaladas en los colmenares: 10 instalados cerca de entornos altamente antropogénicos (Cassilándia - MS, Fortaleza - CE, Maringá - PR, Aquidauana - MS, Rolim de Moura - RO, Riachuelo - SE, Ubirata - PR y Piracicaba - SP) y 10 en sitios de bajo nivel de perturbación humana (Cassilándia - MS, ItapiúnaCE, Uniao da Vitória - PR, Aquidauana - MS, Rolim de Moura - RO, Pacatuba- SE, Erval Seco - RS, Rio Claro - SP). Los índices de tamaño y forma fueron sometidos a análisis de varianza (ANOVA), donde se utilizaron los caracteres evaluados como factores, para verificar las diferencias de tamaño y forma. La asimetría de análisis fluctuante (AF) se llevó a cabo con el fin de comprobar las diferencias bilaterales. Los resultados indican la existencia de la asimetría de la forma del ala (P < 0.001), pero no se observó asimetría del tamaño del ala. Considerando AF como respuesta ambiental y áreas de alto y bajo grado de alteración humana como factor fijo, observamos diferencias significativas (P < 0.05). Los resultados, para la forma de ala de la A. mellifera,muestran que esta característica se somete a más variación durante la ontogenia en comparación con la variación en el tamaño. Llegamos a la conclusión de que las colonias de abejas recogidas en ambientes con niveles más altos de la perturbación humana tienen una mayor asimetría en forma de ala, por lo que la asimetría fluctuante en forma de alas de las abejas puede ser utilizada como un indicador del grado de antropización del medio ambiente.

Differential effects of exercise on brain opioid receptor binding and activation in rats.

Physical exercise stimulates the release of endogenous opioid peptides supposed to be responsible for changes in mood, anxiety, and performance. Exercise alters sensitivity to these effects that modify the efficacy at the opioid receptor. Although there is evidence that relates exercise to neuropeptide expression in the brain, the effects of exercise on opioid receptor binding and signal transduction mechanisms downstream of these receptors have not been explored. Here, we characterized the binding and G protein activation of mu opioid receptor, kappa opioid receptor or delta opioid receptor in several brain regions following acute (7 days) and chronic (30 days) exercise. As regards short- (acute) or long-term effects (chronic) of exercise, overall, higher opioid receptor binding was observed in acute-exercise animals and the opposite was found in the chronic-exercise animals. The binding of [(35) S]GTPγS under basal conditions (absence of agonists) was elevated in sensorimotor cortex and hippocampus, an effect more evident after chronic exercise. Divergence of findings was observed for mu opioid receptor, kappa opioid receptor, and delta opioid receptor receptor activation in our study. Our results support existing evidence of opioid receptor binding and G protein activation occurring differentially in brain regions in response to diverse exercise stimuli. We characterized the binding and G protein activation of mu, kappa, and delta opioid receptors in several brain regions following acute (7 days) and chronic (30 days) exercise. Higher opioid receptor binding was observed in the acute exercise animal group and opposite findings in the chronic exercise group. Higher G protein activation under basal conditions was noted in rats submitted to chronic exercise, as visible in the depicted pseudo-color autoradiograms.

Effects of acute and long-term typical or atypical neuroleptics on morphine-induced behavioural effects in mice.

1. It has been suggested that the high prevalence of drug abuse in schizophrenics is related to chronic treatment with typical neuroleptics and dopaminergic supersensitivity that develops as a consequence. Within this context, atypical neuroleptics do not seem to induce this phenomenon. In the present study, we investigated the effects of acute administration or withdrawal from long-term administration of haloperidol and/or ziprasidone on morphine-induced open-field behaviour in mice. 2. In the first experiment, mice were given a single injection of haloperidol (1 mg/kg, i.p.) or several doses of ziprasidone (2, 4 or 6 mg/kg, i.p.) and motor activity was quantified by the open-field test. The aim of the second experiment was to verify the effects of an acute injection of haloperidol (1 mg/kg) or ziprasidone (6 mg/kg) on 20 mg/kg morphine-induced behaviours in the open-field test. In the third experiment, mice were treated with 1 mg/kg haloperidol and/or 2, 4 or 6 mg/kg ziprasidone for 20 days. Seventy-two hours after the last injection, mice were injected with 20 mg/kg, i.p., morphine and then subjected to the open-field test. Acute haloperidol or ziprasidone decreased spontaneous general activity and abolished morphine-induced locomotor stimulation. 3. Withdrawal from haloperidol or ziprasidone did not modify morphine-elicited behaviours in the open-field test. The results suggest that withdrawal from neuroleptic treatments does not contribute to the acute effect of morphine in schizophrenic patients.

Is it possible to use cross-sectional and vertical facial measurements to establish the shape of the mandibular arch?

BACKGROUND: Given the benefits of radiographic cephalometric studies in determining patterns of dental-skeletal-facial normality in orthodontics, the aim of this study was to investigate the association between mandibular dental arch shape and cross-sectional and vertical facial measurements. MATERIALS AND METHODS: It was analyzed plaster casts and teleradiographs in frontal and lateral norm belonging to 50 individuals, aged between 15 and 19 years, with no previous history of orthodontic treatment and falling into four of the six Andrews's occlusion keys. The plaster models were scanned (3D) and the images of the dental arches were classified subjectively as oval, triangular and quadrangular by three calibrated examiners, with moderate inter-examiner agreement (Kappa = 0.50). After evaluation of the method error by paired t test (p > 0.05), it was carried out the analysis of cross-sectional and vertical facial measurements to be compared to the shape of the dental arch. Data were subjected to one-way analysis of variance with a significance level of 5%. RESULTS: When the VERT index was compared with the three arch shapes, no measurement showed statistically significant differences (p > 0.05): triangular (0.54); oval (0.43); and quadrangular (0.73); as well as there were no differences (p > 0.05) in the widths of the face (141.20; 141.26; 143.27); maxilla (77.27; 77.57; 78.59) and mandible (105.13; 103.96; 104.28). CONCLUSION: It can be concluded that there was no correlation between different shapes of the mandibular dental arch and the cross-sectional and vertical facial measurements investigated.

Biological evaluation of morin and its new oxovanadium(IV) complex as antioxidant and specific anti-cancer agents.

It is known that flavonoids possess, among others, antioxidant and antitumoral properties that depend on their molecular structure. The central objective if this study was to investigate the potential antioxidant and antiproliferative properties of the flavonol morin and its new oxovanadium(IV) complex (VOmor) that was synthesized in order to modify the morin chemical structure. Two osteoblast (UMR106 and MC3T3E1), two breast tumor (T47D and SKBR3) and breast epithelial cell lines in culture were used for the antitumoral determinations. Additionally, a comparative study of their antioxidant capacities using different radicals (DPPH, ABTS(+), OH, O2(-), ROO) was performed. Selected mechanisms of action were studied using the breast cancer cell lines. Results obtained show that morin and its complex behaved as good antioxidant agents for some of the radicals and that the complexation improved the behavior with respect to OH and O2(-) radicals being morin more effective as ROO scavenger. A considerable variation in sensitivity was observed in the breast cancer cells but non-specificity was found for the treatment of osteosarcoma. Moreover, the compounds did not affect the normal proliferation of the breast epithelial mammal cells. The mechanistic studies demonstrated that the complex did not generate reactive oxygen species in the cells (confirming the in vitro studies) and did not produce any damage of DNA. The plasmatic membrane was observed to be damaged only in the SKBR3 cell line. In contrast, the perturbation of the mitochondrial membrane potential and the activation of caspase 3/7 for the breast tumor cells revealed an apoptotic cell death process. All these results collectively suggested that VOmor complex could serve as promising pharmacologically active substance against breast cancer treatment.

A new Corydoras Lacépède, 1803 (Siluriformes: Callichthyidae) from the rio São Francisco basin, Brazil

A new species of Corydoras is described from the rio São Francisco basin in northeastern Brazil, Minas Gerais and Bahia States. The new species is distinguished from most of its congeners by the anterior portion of the infraorbital 1 very large, conspicuously expanded towards the anteroventral margin of the snout and almost entirely covering its lateral margin. Other characters that distinguish the new species are the infraorbital 2 slender on its dorsal tip, contacting only sphenotic and not compound pterotic; and the presence of two laterosensory canals on trunk. A phylogenetic analysis including the new species found it sister-group of C. flaveolus, and both species sister-group of C. paleatus. An identification key to the species of the rio São Francisco basin is also provided.(AU)

Uma espécie nova de Corydoras é descrita da bacia do rio São Francisco no nordeste do Brasil, estados de Minas Gerais e Bahia. A espécie nova se distingue da maioria de suas congêneres por apresentar a porção anterior do infraorbital 1 muito desenvolvida, expandindo-se conspicuamente em direção à margem anteroventral do focinho, quase cobrindo completamente sua margem lateral. Outros caracteres que distinguem a espécie nova são o infraorbital 2 estreito em sua extremidade dorsal, em contato apenas com o esfenótico e não com o pterótico composto, e presença de somente dois canais látero-sensoriais no tronco. Uma análise filogenética incluindo a espécie nova encontrou-a como grupo-irmão de C. flaveolus, e ambas como grupo-irmão de C. paleatus. Uma chave para identificação das espécies da bacia do rio São Francisco também é fornecida.(AU)

A new Corydoras Lacépède, 1803 (Siluriformes: Callichthyidae) from the rio São Francisco basin, Brazil

A new species of Corydoras is described from the rio São Francisco basin in northeastern Brazil, Minas Gerais and Bahia States. The new species is distinguished from most of its congeners by the anterior portion of the infraorbital 1 very large, conspicuously expanded towards the anteroventral margin of the snout and almost entirely covering its lateral margin. Other characters that distinguish the new species are the infraorbital 2 slender on its dorsal tip, contacting only sphenotic and not compound pterotic; and the presence of two laterosensory canals on trunk. A phylogenetic analysis including the new species found it sister-group of C. flaveolus, and both species sister-group of C. paleatus. An identification key to the species of the rio São Francisco basin is also provided.

Uma espécie nova de Corydoras é descrita da bacia do rio São Francisco no nordeste do Brasil, estados de Minas Gerais e Bahia. A espécie nova se distingue da maioria de suas congêneres por apresentar a porção anterior do infraorbital 1 muito desenvolvida, expandindo-se conspicuamente em direção à margem anteroventral do focinho, quase cobrindo completamente sua margem lateral. Outros caracteres que distinguem a espécie nova são o infraorbital 2 estreito em sua extremidade dorsal, em contato apenas com o esfenótico e não com o pterótico composto, e presença de somente dois canais látero-sensoriais no tronco. Uma análise filogenética incluindo a espécie nova encontrou-a como grupo-irmão de C. flaveolus, e ambas como grupo-irmão de C. paleatus. Uma chave para identificação das espécies da bacia do rio São Francisco também é fornecida.

Mortalidade por causas externas em idosos em Minas Gerais, Brasil / Mortality from external causes among elderly in Minas Gerais, Brazil / Mortalidad por causas externas en ancianos en Minas Gerais, Brasil

Perfil dos óbitos dessa faixa etária, em Minas Gerais, Brasil, no período de 1999 a 2008. Os dados foram obtidos a partir do Sistema de Informações sobre Mortalidade do Ministério da Saúde e do Depar tamento de Informática do Ministério da Saúde. Os resultados apontaram coeficientes crescentes de mortalidade em idosos durante os anos estudados. Destacaramse como principais causas as quedas e os acidentes de transporte. Também foram registradas taxas ascendentes doscasos de homicídios e suicídios, especialmente em idosos do sexo masculino. São necessárias medidas preventivas imediatas, pois os idosos se mostram cada vez mais sujeitos às mor tes por causas externas.

Efecto de la privación de sueño sobre la presión arterial en ratas / Effect of sleep deprivation on the blood pressure of rats

Con el objetivo de evaluar el efecto de la privación crónica de sueño sobre la presión arterial sistólica, se estudiaron 3 grupos de 8 ratas Wistar, un grupo control: sin privación de sueño y dos grupos experimentales: privación del sueño total y privación de fase de sueño MOR, durante períodos de 96 h continuas semanales, sin interrupción a lo largo de 2 meses. A dichos grupos se les midió la presión arterial sistólica cada semana antes de iniciar el período de privación de sueño. Al concluir los 2 meses, se les realizó extracción de ambos riñones. Los resultados revelaron que hubo diferencia estadísticamente significativa a partir de la semana 6 entre el grupo control y el grupo con privación del sueño total. En cuanto al estudio histológico de los cortes de los riñones, no se encontró alteración alguna de nefroesclerosis. En el modelo de estudio, la privación de sueño total produce un aumento notable de la presión arterial sistólica, no siendo así en el grupo con privación de fase de sueño MOR. Las alteraciones morfológicas renales no parecen participar en la hipertensión obtenida mediante las técnicas aplicadas.

With the objective of evaluating the effects of chronic sleep deprivation on the systolic blood pressure, three groups of 8 Wistar rats were studied- a control group with no sleep deprivation and two experimental groups subjected to total sleep deprivation and MOR sleep phase deprivation, respectively- for continuous 96h periods weekly throughout 2 months. Systolic blood pressure was taken in all the three groups every week before starting the sleep deprivation period. After two months, their kidneys were extracted. The results yielded that there was a statistically significant difference between the control group and the group subjected to total sleep deprivation. As to the histological study of the kidney cuts, nephrosclerosis alterations were not found. In the study model the total sleep deprivation brings about a remarkable rise in systolic blood pressure, except for the group which underwent MOR sleep phase deprivation and that renal morphological alterations does not seem to be involved in hypertension resulting from the applied techniques.

Caída abrupta del tono muscular al entrar a sueño MOR en el ser humano / Sudden drop of muscle tone at the onset of REM sleep in humans

Relatively low tonic electromyographic activity of the mentalis or sub-mentalis muscles constitutes one of the three electrophysiological signs for identifying rapid eye movement sleep (REM), described in the standardized manual for scoring sleep stages in human subjects. The other two signs, low voltage mixed frequency EEG activity and episodic rapid eye movements are inadequate for delimiting the start of REM sleep, because EEG activity resembles that of stage 1 and rapid eye movements are not constantly present. The term <> tonic EMG and not <> is used according to the standardized manual because tonic EMG shows considerable variation from subject to subject and from session to session, and more important because low EMG values may be reached during other sleep stages. Therefore, REM sleep scoring is based on <> tonic EMG. Despite the relevance of the loss of muscular tone for scoring the start of REM sleep and for sleep disorders -such as narcolepsy and REM sleep behavioral disorder, where loss of muscle tone or the lack of it is implicated-, very few quantitative studies of EMG activity during REM sleep in humans have been performed. Amplitude analysis of mentalis and orbicularis oris muscles and spectral power analysis of suprahyoid, masseter and temporalis muscles have demonstrated that EMG activity is lower during REM than during NREM sleep. The mentalis muscle maintains tonically the lowest values during REM sleep with very low variability during the same REM sleep episode and across REM episodes, except for very brief phasic activations, whereas during NREM sleep muscle tone shows large variations within the same sleep stage and along the night. Only one study exists which analyzes the time course of the loss of tone during the transition from NREM to REM sleep integrating the EMG amplitude. However, it was done for long time windows of 20 seconds that does not allow identifying the precise moment of EMG activity drop. Given that the fall in EMG activity is one of the main keys for REM sleep scoring, the objective of the present investigation is to describe the EMG activity of the mentalis muscle during the NREM-REM sleep transition by analyzing short time windows of two seconds. Ten healthy, young adult, right-handed subjects (5 men and 5 women) participated in the study after giving informed consent. All had regular sleeping habits, were in good health and were free of drugs, medication or caffeine intake as assessed by interviews and questionnaires on sleeping habits and health. Polysomnography (PSG) was recorded using a Grass model 8-20E polygraph with filters set at .03 and 70 Hz. Additionally to EEG (C3-A2 and C4-A1), electroculogram (EOG) and EMG of the mentalis muscle, nasal-oral air flow and EMG of anterior tibialis muscles were recorded to remove those subjects showing signs of sleep apnea or periodic limb movement disorder. EEG, EMG and EOG were digitized at 1024 Hz through an analog-to-digital converter of 12 bits resolution using the acquisition program Gamma (version 4.4). The initiation of the first three REM sleep episodes of one night for each subject was indicated in the PSG recordings, following the standardized rules of the manual for scoring sleep stages of human subjects. The fourth REM sleep episode was not considered for analysis because not all subjects had a fourth REM episode. EMG activity of the mentalis muscle of three 30-second epochs around the start of REM sleep (the previous one, the REM entrance and the posterior one) was analyzed. EMG activity was submitted to Fast Fourier Transform and absolute power for every 250 msec (256 points) was obtained for two broad bands: one from 24 to 28 Hz and the other from 28 to 32 Hz, as these have demonstrated significant differences between REM and NREM sleep, in previous studies. Absolute power values were log-transformed previous to statistical analysis to approximate them toward normal distribution. The time course of the drop in muscle tone was established in the case of each individual NREM-REM sleep transition for two second time windows, both visually on the EMG signal and also by statistically comparing consecutive 2-second averages of EMG absolute power (8 means of 250 msec). When there was no clear visual or statistical evidence of decreased EMG activity, the 30-second epoch was divided in half. Additionally, the first rapid eye movement was visually identified. EMG signals were visually inspected and absolute power values of two-second epochs containing eye movement or phasic EMG artifacts were substituted by the average of the preceding and following two-second means. This procedure was chosen instead of rejection in order to maintain the time sequence. The average of substituted epochs was lower than 1 for the NREM-REM sleep transitions. Once the significant differences were established for the individual NREM-REM sleep transitions, the absolute power for the 20 seconds prior and the 20 seconds after the turning point was averaged for the group and compared using the Student t test. A level of p <0.05 was required for significance for both individual and group analyses. EMG drop was statistically identified in 15 out of the 30 NREM-REM sleep transitions (p < 0.05). In 14 cases more than one significant difference was found due to phasic increases shorter than two seconds. Thus, EMG drop was established where both visual inspection of EMG signal and statistical differences were matched. It was necessary to divide the 30-second epoch in half just in one individual case. The comparison of EMG power after averaging for the group the 20 seconds before and the twenty seconds after the individual turning point showed that EMG absolute power was significantly different for the two bands (p < 0.0001 for both bands). The first eye movement occurred after the EMG drop in 28 out of the 30 NREM-REM sleep transitions within a range of 2 and 52 seconds. EMG fall was simultaneous to the first eye movement in one case and eye movement preceded EMG drop in just one NREM-REM sleep transition. Present results indicate that the loss of muscle tone of the mental is muscle during the transition from NREM to REM sleep occurs suddenly rather than gradually, within a time window lasting no longer than 2 sec. This could be appreciated in individual as well as in group analysis. It still remains a matter of debate if REM sleep is under the control of a single generator that simultaneously commands the start of all of its physiological changes, or if each of the physiological systems involved in REM sleep is under its own command starting at its own time and are only orchestrated by a common mechanism. The loss of muscle tone occurred before the first rapid eye movement in 29 out of 30 of the REM sleep onset episodes analyzed, upholding the proposition that physiological systems involved in REM sleep follow different time courses in agreement with non-simultaneous onset of the different physiological mechanisms as it happens with ponto-geniculate-occipital waves in cats that begin long before EEG desynchronization and EMG fall and with results observed in two studies in man which report that EMG amplitude decreases before eye movements. The sudden drop in muscle tone during NREM-REM sleep transition may help to understand the physiological mechanisms involved in sleep disorders where loss of muscle tone or the lack of it is implicated, such as narcolepsy and REM sleep behavioral disorder. It can also be used as an objective sign to establish the onset of REM sleep in research where the precise moment of REM sleep onset is needed. The time relationship among muscle tone fall and other physiological signs of REM sleep remains to be investigated.

De acuerdo con el manual estandarizado para la clasificación del sueño en el ser humano, tres variables fisiológicas marcan el inicio del sueño con movimientos oculares rápidos (MOR): la desincronización electroencefalográfica (EEG), los movimientos oculares rápidos y la pérdida de tono muscular. De estos tres indicadores, uno de ellos, los movimientos oculares rápidos, es una manifestación intermitente o fásica que consiste en movimientos que pueden ser aislados o emitirse en salvas de varios movimientos, pero que no está presente de manera continua. Los otros dos, la desincronización EEG y la atonía, aparecen desde el inicio y se mantienen durante todo el episodio de sueño MOR. Sin embargo, la actividad EEG del sueño MOR en el ser humano es muy semejante, bajo inspección visual, al EEG de la etapa 1, por lo que el EEG y los movimientos oculares rápidos no permiten determinar por sí solos el inicio del sueño MOR, por lo que la atonía muscular se hace indispensable para ello. A pesar de que la caída de tono muscular es uno de los principales indicadores del sueño con movimientos oculares rápidos (MOR) y de la importancia que tiene la actividad muscular durante esta etapa del sueño para comprender mejor los trastornos en que se encuentra alterada la pérdida del tono muscular, como la narcolepsia y el trastorno conductual del sueño MOR, son muy escasas las investigaciones sobre el curso temporal de la caída del tono muscular durante la transición del sueño NMOR al MOR en el ser humano. Dado que la caída del tono muscular es uno de los principales indicadores del SMOR y que ni la desincronización electroencefalográfica ni los movimientos oculares rápidos permiten señalar con precisión la entrada al sueño MOR, el principal objetivo de esta investigación es caracterizar el curso temporal de la disminución del tono del músculo mentalis por ventanas de dos segundos y describir en detalle su curso temporal durante la transición del sueño NMOR al MOR. El establecimiento del cambio EMG en el tiempo permitirá contar con un signo objetivo de la entrada al SMOR que contribuirá a comprender mejor los trastornos del sueño. Con este objetivo, se registró el sueño de 10 adultos jóvenes, sanos y diestros (cinco hombres y cinco mujeres). La polisomnografía (PSG) y la clasificación de las etapas del sueño se realizaron de acuerdo con los procedimientos habituales. Se identificaron las tres primeras entradas a sueño MOR de la noche. Se analizó el EMG del mentón de tres épocas de 30 segundos del periodo de inicio del SMOR (IMOR), una antes, una durante y otra después. Para cada sujeto y episodio de SMOR, se calculó el espectro de potencia absoluta (PA) para dos bandas anchas del EMG para épocas de 250 milisegundos. Se determinó individualmente para cada entrada a sueño MOR la evolución temporal de la caída del tono muscular del IMOR, promediando la PA para cada dos segundos, y se excluyeron los segmentos con artefactos. Se estableció la caída del tono muscular al encontrar diferencias significativas entre dos épocas consecutivas, así como visualmente en el trazo EMG. Posteriormente, se promedió la PA de 10 segmentos de dos segundos previos y de 10 segmentos posteriores a la caída del EMG para todo el grupo y se compararon por medio de la prueba t de Student para muestras correlacionadas. La caída del tono muscular en la transición del sueño NMOR al MOR ocurrió de manera abrupta y no paulatina en un intervalo no mayor a dos segundos. Los resultados estadísticos detectaron la caída del tono muscular tanto en los análisis individuales como de grupo. La aparición de la pérdida de tono muscular ocurrió antes del primer movimiento ocular en 29 de las 30 entradas a MOR analizadas. Estos resultados apoyan la observación de que los diversos sistemas fisiológicos involucrados en el sueño MOR entran en acción en diferentes momentos y no simultáneamente. La caída brusca del tono muscular puede constituir un indicador para determinar objetivamente la entrada al sueño MOR que a su vez se puede emplear para estudiar la pérdida del tono muscular en otras alteraciones, como la narcolepsia y el trastorno conductual del sueño MOR, así como en investigaciones que requieran establecer el momento preciso de la entrada al sueño MOR.