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BACKGROUND AND HYPOTHESIS: Remote monitoring (RM) of patients on automated peritoneal dialysis (APD) prevent complications and improve treatment quality. We analyzed the effect of RM-APD on mortality and complications related to cardiovascular disease (VD), fluid overload and insufficient dialysis efficiency. METHODS: In a cluster-randomized, open-label, controlled trial, 21 hospitals with APD programs were assigned to use either RM-APD (10 hospitals; 403 patients) or conventional APD (11 hospitals; 398 patients) for the treatment of adult patients starting PD. Primary outcomes were time to first event of: 1) Composite Index-1 comprising all-cause mortality, first adverse events and hospitalizations of any cause, and 2) Composite Index-2 comprising cardiovascular mortality, first adverse event and hospitalizations related to CVD, fluid overload and insufficient dialysis efficiency. Secondary outcomes were time to first event of individual components of the two composite indices, and rates of adverse events, hospitalizations, unplanned visits, and transfer to hemodialysis. Patients were followed for a median of 9.5 months. Primary outcomes were evaluated by competing-risk analysis and restricted mean survival time (RMST) analysis. RESULTS: While time to reach Composite Index-1 did not differ between the groups, Composite Index-2 was reached earlier (ΔRMST: -0.85 months; p=0.02), and all-cause mortality (55 vs. 33 deaths, p=0.01; sHR 1.69 (95%CI 1.39-2.05), p<0.001) and hospitalizations of any cause were higher in APD group than in RM-APD as were cardiovascular deaths (24 vs. 13 deaths, p=0.05; sHR 2.44 (95%CI 1.72 - 3.45), p<0.001) and rates of adverse events and hospitalizations related to CVD, fluid overload or insufficient dialysis efficiency. Dropouts were more common in the APD group (131 vs. 110, p=0.048). CONCLUSIONS: This randomized controlled trial shows that remote monitoring may add significant advantages to APD, including improved survival and reduced rate of adverse events and hospitalizations, which can favorably impact the acceptance and adoption of the therapy.

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Introduction/aim: Hyperphosphatemia is a mortality risk factor in dialysis patients; however, low phosphorus levels too. Diabetes and malnutrition are strongly associated with mortality and with reduced serum phosphorus. This study analyzed the pattern of serum phosphorus in patients on Peritoneal Dialysis (PD) and its association with mortality. Methods: A Secondary analysis was performed on a multicenter cohort study in peritoneal dialysis patients from two previous studies done by our group. Results: Six hundred fifty-four patients were included. Serum phosphorus was <3.6 mg/dL in 28.29% of patients, 3.6 to 5.2 mg/dL in 48.16%, and >5.2 mg/dL in 23.55%. In logistic regression analysis; education, age, and hypoalbuminemia were risk factors for low P levels. In multivariate Cox analysis P < 3.6 mg/dL, age, and low albumin were predictors for all-cause mortality. When lower P and lower albumin were combined, this group had the highest risk for all cause and cardiovascular mortality. Conclusion: The frequency of patients with reduced serum phosphorus was higher in the Mexican population than in Europe or Asia. Low serum phosphorus levels, older age and hypoalbuminemia were risk factors for all-cause mortality. Low phosphorus combined with low albumin levels were the highest risk factor for all-cause and cardiovascular mortality.

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OBJECTIVE: Takayasu arteritis (TAK) is a rare chronic granulomatous vasculitis that affects large vessels and usually begins in women of childbearing age, so it is not uncommon for pregnancies to occur in these patients. However, there is limited information about these pregnancies, with reports of adverse maternal and obstetric outcomes. The objective of this study is to evaluate adverse maternal, fetal and neonatal events in pregnant patients with TA. METHODS: This is a cross-sectional study with retrospective data collection. We reviewed 22 pregnancies in 18 patients with TAK, according to the American College of Rheumatology criteria, that were followed up in a high-risk prenatal clinic specialized in systemic autoimmune diseases and thrombophilia (PrAT) at Hospital Universitário Pedro Ernesto, from 1998 to 2021. RESULTS: In twenty-two pregnancies, the mean age of patients was 28.09 years and the mean duration disease was 10.9 years. Of the 18 patients with TAK studied, only one had the diagnosis during pregnancy and had active disease. All other patients had a previous diagnosis of TAK and only 3 had disease activity during pregnancy. Twelve patients (66.6%) had previous systemic arterial hypertension and eleven (61.1%) had renal involvement. Among maternal complications, eight patients (36.3%) developed preeclampsia and six (27.2%) had uncontrolled blood pressure without proteinuria, while 10 (45%) had puerperal complications. Four (18.1%) births were premature, all due to severe preeclampsia and eight newborns (34.7%) were small for gestational age. When all maternal and fetal/neonatal outcomes included in this study were considered, only 6 (27.2%) pregnancies were uneventful. CONCLUSION: Although there were no maternal deaths or pregnancy losses in this study, the number of adverse events was considerably high. Hypertensive disorders and small for gestational age newborns were more common than general population, while the number of patients with active disease was low. These findings suggest that pregnancies in patients with TAK still have several complications and a high-risk prenatal care and delivery are necessary for these patients.

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Objetivo: compreender o conhecimento e a percepção de enfermeiros quanto à sedação paliativa em oncologia. Método: estudo qualitativo, exploratório e descritivo, com delineamento transversal. Participaram do estudo 16 enfermeiros atuantes na oncologia de um hospital de referência localizado ao norte do Rio Grande do Sul. A coleta de dados ocorreu por meio de entrevista gravada com duração de aproximadamente 10 minutos, sendo aplicado um roteiro de perguntas fechadas com a finalidade de caracterizar os enfermeiros participantes da pesquisa, e perguntas abertas e específicas para contemplar o objetivo do estudo. O método utilizado para o diagnóstico e verificação dos dados da pesquisa foi a análise de conteúdo de Bardin. Os dados foram analisados e codificados por meio do software NVivo 10, que gerou categorias de similaridade e correlações. Resultados: surgiram cinco categorias intituladas "Conhecimento sobre sedação paliativa; Percepção sobre sedação paliativa na oncologia; Sentimentos em relação à sedação paliativa aos pacientes oncológicos; Vivência em relação à sedação paliativa em pacientes oncológicos e Participação do enfermeiro no procedimento de sedação paliativa". Conclusão: o enfermeiro atua de forma efetiva e fundamental na prestação do cuidado e na avaliação do paciente em sedação paliativa, mas ainda encontram-se diversos obstáculos relacionados à participação na tomada de decisões. Evidencia-se a importância de novas pesquisas sobre a temática, como também a implementação de protocolos que subsidiem na indicação da sedação paliativa.(AU)

Objective: to understand the knowledge and perception of nurses dealing with palliative sedation in oncology. Method: this is a qualitative, exploratory, and descriptive study, with a cross-sectional design. The study included 16 nurses working in oncology at a reference hospital located in the north of Rio Grande do Sul. Data were collected through recorded interviews lasting approximately 10 minutes, with a script of closed questions being applied to characterize the nurses participating in the research, and open and specific questions, to contemplate the objective of the study. The method used for the diagnosis and verification of research data was Bardin's content analysis. Data were analyzed and coded using the NVivo 10 software, which generated categories of similarity and correlations. Results: five categories emerged: (i) Knowledge about palliative sedation; (ii) Perception of palliative sedation in oncology; (iii) Feelings regarding palliative sedation in cancer patients; (iv) Experience with palliative sedation in cancer patients; and (v) Participation of the nurse in the palliative sedation procedure. Conclusion: nurses act effectively and fundamentally in providing care and evaluating patients undergoing palliative sedation, but there are still several obstacles related to their participation in decision-making. The importance of new research on the subject is evident, as well as the implementation of protocols that support the indication of palliative sedation.(AU)

Objetivo: comprender el conocimiento y la percepción de los enfermeros sobre la sedación paliativa en oncología. Método: estudio cualitativo, exploratorio y descriptivo, con diseño transversal. El estudio abarcó 16 enfermeros que trabajaban en oncología en un hospital de referencia localizado en el norte de Rio Grande do Sul. La colecta de datos ocurrió por medio de entrevista grabada con duración aproximada de 10 minutos, siendo aplicado un guión de preguntas cerradas con la finalidad de caracterizar los enfermeros participantes de la investigación, y preguntas abiertas y específicas para contemplar el objetivo del estudio. El método utilizado para el diagnóstico y verificación de los datos de la investigación fue el análisis de contenido de Bardin. Los datos fueron analizados y codificados utilizando el software NVivo 10, que generó categorías de similitud y correlaciones. Resultados: surgieron cinco categorías tituladas "Conocimientos sobre sedación paliativa; Percepción de la sedación paliativa en oncología; Sentimientos con respecto a la sedación paliativa para pacientes con cáncer; Experiencia con sedación paliativa en pacientes oncológicos y participación de Enfermeros en el procedimiento de sedación paliativa". Conclusión: el enfermero actúa de forma eficaz y fundamental en la prestación del cuidado y en la evaluación del paciente en sedación paliativa, pero aún existen varios obstáculos relacionados con la participación en la toma de decisiones. Es evidente la importancia de seguir investigando sobre el tema, así como la implementación de protocolos que sustenten la indicación de la sedación paliativa.(AU)

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Abstract Objective Takayasu arteritis (TAK) is a rare chronic granulomatous vasculitis that affects large vessels and usually begins in women of childbearing age, so it is not uncommon for pregnancies to occur in these patients. However, there is limited information about these pregnancies, with reports of adverse maternal and obstetric outcomes. The objective of this study is to evaluate adverse maternal, fetal and neonatal events in pregnant patients with TA. Methods This is a cross-sectional study with retrospective data collection. We reviewed 22 pregnancies in 18 patients with TAK, according to the American College of Rheumatology criteria, that were followed up in a high-risk prenatal clinic specialized in systemic autoimmune diseases and thrombophilia (PrAT) at Hospital Universitário Pedro Ernesto, from 1998 to 2021. Results In twenty-two pregnancies, the mean age of patients was 28.09 years and the mean duration disease was 10.9 years. Of the 18 patients with TAK studied, only one had the diagnosis during pregnancy and had active disease. All other patients had a previous diagnosis of TAK and only 3 had disease activity during pregnancy. Twelve patients (66.6%) had previous systemic arterial hypertension and eleven (61.1%) had renal involvement. Among maternal complications, eight patients (36.3%) developed preeclampsia and six (27.2%) had uncontrolled blood pressure without proteinuria, while 10 (45%) had puerperal complications. Four (18.1%) births were premature, all due to severe preeclampsia and eight newborns (34.7%) were small for gestational age. When all maternal and fetal/neonatal outcomes included in this study were considered, only 6 (27.2%) pregnancies were uneventful. Conclusion Although there were no maternal deaths or pregnancy losses in this study, the number of adverse events was considerably high. Hypertensive disorders and small for gestational age newborns were more common than general population, while the number of patients with active disease was low. These findings suggest that pregnancies in patients with TAK still have several complications and a high-risk prenatal care and delivery are necessary for these patients.

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The purpose of this study was to compare vascular calcification (VC), serum osteoprotegerin (OPG) levels, and other biochemical markers to determine their value as available predictors of all-cause and cardiovascular (CV) mortality in patients on peritoneal dialysis (PD). A total of 197 patients were recruited from seven dialysis centers in Mexico City. VC was assessed with multi-slice computed tomography, measured using the calcification score (CaSc). OPG, albumin, calcium, hsC-reactive protein, phosphorous, osteocalcin, total alkaline phosphatase, and intact parathormone were also analyzed. Follow-up and mortality analyses were assessed using the Cox regression model. The mean age was 43.9 ± 12.9 years, 64% were males, and 53% were diabetics. The median OPG was 11.28 (IQR: 7.6−17.4 pmol/L), and 42% of cases had cardiovascular calcifications. The median VC was 424 (IQR:101−886). During follow-up (23 ± 7 months), there were 34 deaths, and 44% were cardiovascular in origin. In multivariable analysis, OPG was a significant predictor for all-cause (HR 1.08; p < 0.002) and CV mortality (HR 1.09; p < 0.013), and performed better than VC (HR 1.00; p < 0.62 for all-cause mortality and HR 1.00; p < 0.16 for CV mortality). For each mg/dL of albumin-corrected calcium, there was an increased risk for CV mortality, and each g/dL of albumin decreased the risk factor for all-cause mortality. OPG levels above 14.37 and 13.57 pmol/L showed the highest predictive value for all-cause and CV mortality in incident PD patients and performed better than VC.

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Traumatic brain injury (TBI) is the leading cause of death and disability for children and young adults. The Glasgow Coma Scale allows to classify TBI as mild, moderate and severe. Imaging studies show the heterogeneity of the diagnosis. Primary injury is caused by mechanical impact. Secondary injury contributes significantly to prognosis by exacerbating hypoperfusion and intracranial hypertension. Even in the absence of extracranial lesions, many patients with severe TBI present significant organ dysfunction, which transforms TBI into a multisystemic pathology. Most relevant systems compromised include cardiovascular, autonomic, respiratory and coagulation. The main aims of anesthetic management are: early decompression together with prevention, early detection, and management of determinants of secondary injury. To date, there are no techniques or drugs showing a significant impact on the outcome of TBI patients. On the other hand, maintaining good hemodynamic stability, adequate oxygenation and normocarbia all contribute to a better outcome.

El trauma encéfalocraneano (TEC) es la causa más importante de muerte y discapacidad de niños y adultos jóvenes. La escala de Glasgow permite clasificarlo en leve, moderado y severo. La imagenología da cuenta de la heterogeneidad del diagnóstico. La injuria primaria es la causada por el impacto mecánico. La injuria secundaria contribuye significativamente al pronóstico al exacerbar la hipoperfusión y la hipertensión endocraneana. Aun en ausencia de lesiones extracraneales, gran parte de los pacientes con TEC severo presenta disfunción orgánica significativa, lo que lo transforma en una patología multisistémica. Destacan el compromiso cardiovascular, autonómico, respiratorio y trastornos de la coagulación, entre otros. Los objetivos del manejo anestésico son: la descompresión precoz junto con la prevención, detección temprana y manejo de factores determinantes de injuria secundaria. No existe evidencia respecto de técnicas ni fármacos que hayan demostrado un impacto significativo en el manejo del TEC, más bien, impacta positivamente el mantener la estabilidad hemodinámica, una adecuada oxigenación y normocarbia.

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Resumen La sororidad engloba las prácticas de colaboración y soporte en las relaciones entre mujeres y es el espacio propicio para la construcción de nuevas formas de significar la vejez femenina. El objetivo de este estudio cualitativo fue describir y categorizar los tipos de configuraciones vinculares que se mantienen y los que se han transformado en pro a la sororidad en los procesos de envejecimiento femenino, por medio del análisis narrativo de una entrevista profunda grupal. Los resultados muestran la necesidad de implementar políticas y acciones en aras de disminuir el ageism con relación al envejecimiento de mujeres. La construcción de la sororidad ayuda en el empoderamiento colectivo en pro de su género. La sexualidad de la mujer mayor sigue siendo un tema pendiente en la agenda de la investigación y la discusión en los estudios feministas, lo que nos lleva a concluir que, a pesar de la existencia de diferencias individuales en los propios procesos de envejecimiento, las mujeres se experimentan y comparten en una misma condición histórica, por ello es en colectivo que la acción de la sororidad se pronuncia como vía en la generación de nuevas narrativas preferidas por las mujeres. Finalmente, se expone una propuesta para trabajar la percepción del cuerpo femenino en el proceso de envejecer, y la construcción de la sororidad, desde las prácticas narrativas de White y Epston.

Abstract Sorority encompasses the practices of collaboration and support in relations between women and is the propitious space for the construction of new ways to signify female old age. We present results of a qualitative study using focus groups, which aimed to describe and categorize the types of relational configurations that remain unchanged or change towards sorority in the female aging process. Findings describe the need to implement actions to reduce ageism, not only in terms of the experiences women go through, but also towards aging in general. One of the measures we can take is undoubtedly the construction of women circle sorority, which leads to collective empowerment of gender. The female body is a focus of attention in terms of what it lives and experiences, and the right to have love and sexuality throughout life is also highlighted. We then created an intervention proposal to work on the perception of the female body and its experience in the aging process. The proposed intervention is a workshop, based on the narrative model of Michael White and David Epston.

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BACKGROUND: Arterial calcification (AC) is frequent in patients with end stage renal disease and is also considered a risk factor for later morbidity and mortality. However, long-term factors associated with the process are not well known. We analyzed the trends over time of biomarkers related with development and progression of AC in incident patients on peritoneal dialysis (PD). METHODS: We performed a prospective study with 186 patients on PD followed up for 1 year. We analyzed the progression of AC in the abdominal aorta and pelvic vessels by calcification score (CaSc), using16-cut computerized multidetector tomography at baseline and 1 year. Variables related with PD treatment, inflammation, and mineral metabolism were measured at baseline, 6, and 12 months of follow-up. Changes in biochemical variables were analyzed for their relationship with changes in AC. RESULTS: Over 1 year, the number of patients with AC increased from 47 to 56%, and CaSc from 355 (interquartile range [IQR] 75-792) to 529 (IQR 185-1632). A total of 43.5% of patients remained free of calcification, 11.7% had new calcifications, and 44.8% had progression of calcification. Older age, diabetes, high systolic blood pressure, body mass index, cholesterol, and osteoprotegerin (OPG), as well as lower levels of albumin, serum creatinine, and osteocalcin, were associated with development of new, and rapid progression of, calcification. In multivariate logistic analysis, OPG remained the most significant (OR 1.27, 95% CI 1.11-1.47, p < 0.001). CONCLUSION: OPG was the strongest risk factor associated with new development and rapid progression of AC in incident PD patients.

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BACKGROUND/AIMS: Diastolic dysfunction (DD) and low levels of thyroid hormones (TH) are frequent found in chronic kidney disease; both are associated with all-cause and cardiovascular mortality. However, a link between them has not yet been established. The aim of this study was to analyze DD as a surrogate marker of fibrosis and its association with TH in incident patients on peritoneal dialysis (PD). METHODS: A cross-sectional study with 183 incident patients on PD with preserved ejection fraction was performed. Clinical and demographic data were registered. Serum total and free (t/f) triiodothyronine (T3), thyroxin (T4), and thyroid stimulating hormone levels were determined by RIA kits, albumin and high-sensitivity C-reactive protein by conventional assays. Transthoracic 2D echocardiogram was performed for evaluation of left ventricular (LV) mass and ejection fraction. DD was evaluated using pulsed-wave tissue Doppler imaging. RESULTS: Patients were 43 ± 12, 42% with diabetes mellitus (DM). Some degree of DD was found in 62% of patients; 18% had grade I DD, 8% grade II DD and 36% grade III DD. Patients with grade III DD were more likely to have diabetes, older, high LV mass and low serum albumin, t/fT3 and tT4 levels. In logistic multivariate regression analysis, it was found that diabetes (B = -0.86, 95% CI 0.182-0.992, p < 0.05), hypertension (B = -0.95, 95% CI 0.184-0.817, p = 0.01) and tT3 (B = -1.94, 95% CI 0.023-0.876, p < 0.05) were associated with grade III DD. CONCLUSIONS: High prevalence of grade III DD was found in incident patients on PD. In addition to DM and hypertension, tT3 was found to be an independent risk factor for grade III DD and more studies are needed to understand the reasons as to why this association is present.

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BACKGROUND AND AIMS: Thyroid hormones exert important effects on heart remodeling through mir-208. The process may have a role in myocardial changes in chronic kidney disease where thyroid abnormalities are common. In this study the effect of T4 supplementation on left ventricle (LV) remodeling in 5/6 nephrectomized rats (5/6Nx) was analyzed. METHODS: 5/6Nx rats and 5/6Nx under T4 supplementation (5/6Nx + T4) were compared with control (C) and thyroidectomized (Tx) rats. After 8 weeks of follow-up, LV was analyzed for α-MHC, ß-MHC, TGF-ß, and mir-208 expression, hydroxyproline content, and myocardial fibrosis. Serum collagenase activity was also analyzed. RESULTS: Heart weight increased in 5/6Nx rats compared to C, which was prevented with T4 supplementation (C, 1.5 ± 0.04; 5/6Nx, 1.8 ± 0.09; 5/6Nx + T4, 1.6 ± 0.07 g, p <0.05). The same pattern was seen for LV wall thickness, hydroxyproline content, LV fibrosis, and mRNA TGF-ß expression (C, 0.47 ± 0.17; 5/6Nx, 10.55 ± 3.4; 5/6Nx + T4, 3.01 ± 0.52, p <0.01). Tx rats had reduction in heart weight, increased LV wall thickness, and fibrosis. Collagenase activity did not change in any group. mRNA expression of α-, ß-MHC, and TGF-ß increased in 5/6Nx in comparison to C and 5/6Nx + T4. Expression of mir-208 decreased in 5/6Nx groups, and levels were restored with T4 supplementation (4.21 ± 0.28, 3.39 ± 0.29, and 4.26 ± 0.37 RU, respectively, p <0.01). CONCLUSIONS: Decreased plasma level of thyroid hormones or sensitivity at tissue level observed in chronic kidney disease induced by 5/6Nx has an important effect in heart remodeling processes, some of it related or mediated by mir-208 and TGF-ß expression in the heart.

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This paper is a compilation of data from investigations made with marine benthic algae from the Magellan Region that have biotechnological utilization in human consumption or medicine or as a source of phycolloids or food supplements or animal feed. The most important Rhodophyta species are: Ahnfeltia plicata (Hudson) E.M. Fries for agarose production, Gigartina skottsbergii Setchell & N.L.Gardner for carrageenan production, and Callophyllis variegata (Bory de Saint-Vincent) Kützing for human consumption. The most important Heterokontophyta species are: Macrocystis pyrifera (L.) C. Agardh, and Durvillaea antarctica (Chamisso) Hariot for human consumption, alginate production, and as biofertilizer for agricultural crops. M. pyrifera is also used as a food supplement for salmon, chickens, quails, sheep and bovines and for biofuel production.

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Traumatic brain injury (TBI) results in dysfunction of the cerebrovasculature. Gap junctions coordinate vasomotor responses and evidence suggests that they are involved in cerebrovascular dysfunction after TBI. Gap junctions are comprised of connexin proteins (Cxs), of which Cx37, Cx40, Cx43, and Cx45 are expressed in vascular tissue. This study tests the hypothesis that TBI alters Cx mRNA and protein expression in cerebral vascular smooth muscle and endothelial cells. Anesthetized (1.5% isoflurane) male Sprague-Dawley rats received sham or fluid-percussion TBI. Two, 6, and 24 h after, cerebral arteries were harvested, fresh-frozen for RNA isolation, or homogenized for Western blot analysis. Cerebral vascular endothelial and smooth muscle cells were selected from frozen sections using laser capture microdissection. RNA was quantified by ribonuclease protection assay. The mRNA for all four Cx genes showed greater expression in the smooth muscle layer compared to the endothelial layer. Smooth muscle Cx43 mRNA expression was reduced 2 h and endothelial Cx45 mRNA expression was reduced 24 h after injury. Western blot analysis revealed that Cx40 protein expression increased, while Cx45 protein expression decreased 24 h after injury. These studies revealed significant changes in the mRNA and protein expression of specific vascular Cxs after TBI. This is the first demonstration of cell type-related differential expression of Cx mRNA in cerebral arteries, and is a first step in evaluating the effects of TBI on gap junction communication in the cerebrovasculature.

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Experimental evidence suggests that random, spontaneous (stochastic) fluctuations in gene expression have important biological consequences, including determination of cell fate and phenotypic variation within isogenic populations. We propose that fluctuations in gene expression represent a valuable tool to explore therapeutic strategies for patients who have suffered traumatic brain injury (TBI), for which there is no effective drug therapy. We have studied the effects of TBI on the hippocampus because TBI survivors commonly suffer cognitive problems that are associated with hippocampal damage. In our previous studies we separated dying and surviving hippocampal neurons by laser capture microdissection and observed unexplainable variations in post-TBI gene expression, even though dying and surviving neurons were adjacent and morphologically identical. We hypothesized that, in hippocampal neurons that subsequently are subjected to TBI, randomly increased pre-TBI expression of genes that are associated with neuroprotection predisposes neurons to survival; conversely, randomly decreased expression of these genes predisposes neurons to death. Thus, to identify genes that are associated with endogenous neuroprotection, we performed a comparative, high-resolution transcriptome analysis of dying and surviving hippocampal neurons in rats subjected to TBI. We found that surviving hippocampal neurons express a distinct molecular signature--increased expression of networks of genes that are associated with regeneration, cellular reprogramming, development, and synaptic plasticity. In dying neurons we found decreased expression of genes in those networks. Based on these data, we propose a hypothetical model in which hippocampal neuronal survival is determined by a rheostat that adds injury-induced genomic signals to expression of pro-survival genes, which pre-TBI varies randomly and spontaneously from neuron to neuron. We suggest that pharmacotherapeutic strategies that co-activate multiple survival signals and enhance self-repair mechanisms have the potential to shift the cell survival rheostat to favor survival and therefore improve functional outcome after TBI.

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The exploitation of seaweeds in Chile has been carried out for more than 60 years. More recently, seaweeds have been used for the production of alginate, agar and carrageenan, agricultural fertilizers and industrial aquaculture (feed for abalone and sea urchins), increasing the added value of this natural resource. In the Magellan Region (56ºS), the giant kelp Macrocystis pyrifera (L.) C. Agardh presents the most extensive kelp forest, reaching a biomass of approximately 12 kg.m-2. Recent studies have shown potential benefits from adding M. pyrifera- derived flour to salmonid feed. Research is currently underway to evaluate the useof brown algae-derived products for marine aquaculture feed of Oncorhynchus mykiss in tanks. There was no apparent adverse effect on the evaluated parameters that can be attributed to the incorporation of M. pyrifera meal in the diets fed to salmonids. Even when the control diet had numerically the best performance in zootechnical terms, the analysis of variance of all parameters evaluated showed no significant differences with regard to diets containing M. pyrifera meal. These results demonstrated that seaweed meal has important benefits for animal health and nutrition that could be applied or tested in other marine organisms of commercial importance.

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BACKGROUND: The influence of the Bsm1 polymorphism of the vitamin D receptor (VDR) gene on mineral and bone disorders in chronic kidney disease (CKD) is still under discussion. The aim of this study was to analyse the relationship between VDR polymorphism, bone mineral density (BMD), biochemical bone markers and clinical factors in women on peritoneal dialysis (PD) and haemodialysis (HD). METHODS: In a cross-sectional study, 197 women (42 +/- 10 years; 25% with diabetes mellitus (DM); body mass index (BMI) 25.26 +/- 4.77 kg/m(2)) treated by PD (72%) or HD (28%) underwent measurements of BMD (measured at the calcaneus by quantitative ultrasound; expressed as T- and Z-scores) and plasma total calcium (tCa), intact parathyroid hormone 1-84 (iPTH), phosphorus, albumin, glucose, osteoprotegerin (OPG), fetuin-A, intact osteocalcin-49 and N-MID fragment 1-43 aa (N-MID osteocalcin) N-terminal propeptide of type 1 procollagen (PINP) and C-terminal telopeptide-beta aspartic acid (BCL). DNA was extracted from peripheral blood. PCR products were digested with Bsm1 to analyse VDR polymorphism. RESULTS: The Z-score of BMD was -1.1 +/- 1.03. According to the values of osteopenia (T-score = -1.0), patients with higher BMD were younger, had lower frequency of amenorrhoea and diabetes and had higher serum creatinine and fetuin levels as well as lower levels of PINP. In a stepwise multivariate logistics analysis, osteopenia was associated with presence of genotype BB+Bb (OR = 3.26, P < or = 0.003) and age (OR = 0.95, P = 0.050). According to the B allele, bb: n = 126 (64%) and BB+Bb: n = 71(36%), group bb had significantly higher mean Z-scores (-0.97 +/- 1.0 vs -1.3+/-0.92; P < or = 0.021). CONCLUSIONS: The high frequency of osteopenia observed in female CKD patients on dialysis is associated with age and genetic predisposition as revealed by its association to the Bsm1 VDR polymorphism.

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Peroxynitrite is a powerful oxidant capable of nitrating phenolic moieties, such as tyrosine or tyrosine residues in proteins and increases after traumatic brain injury (TBI). First, we tested the hypothesis that TBI increases nitrotyrosine (NT) immunoreactivity in the brain by measuring the number of NT-immunoreactive neurons in the cerebral cortex and hippocampus of rats subjected to parasagittal fluid-percussion TBI. Second, we tested the hypothesis that treatment with L-arginine, a substrate for nitric oxide synthase, further increases NT immunoreactivity over TBI alone. Rats were anesthetized with isoflurane and subjected to TBI, sham TBI, or TBI followed by treatment with L-arginine (100 mg/kg). Twelve, 24, or 72 h after TBI, brains were harvested. Coronal sections (10 microm) were incubated overnight with rabbit polyclonal anti-NT antibody, rinsed, and incubated with a biotinylated secondary antibody. The antigen-antibody complex was visualized using a peroxidase-conjugated system with diaminobenzidine as the chromagen. The number of NT-positive cortical and hippocampal neurons increased significantly in both ipsilateral and contralateral hemispheres up to 72 h after TBI compared with the sham-injured group. Remarkably, treatment with L-arginine reduced the number of NT-positive neurons after TBI in both cortex and hippocampus. Our results indicate that L-arginine actually prevents TBI-induced increases in NT immunoreactivity.

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BACKGROUND: : Resuscitation with hypertonic saline or hypertonic saline plus l-arginine acutely improves cerebral blood flow after traumatic brain injury (TBI) followed by hemorrhagic hypotension. The authors investigated whether hypertonic saline or hypertonic l-arginine would improve long-term neuronal survival and behavioral outcomes 15 days after TBI and hemorrhagic hypotension. METHODS: : Mean arterial pressure, arterial blood gases, pH, plasma glucose, hematocrit, and hemoglobin were measured in male Sprague-Dawley rats before and after moderate (2.0 atm) fluid percussion TBI. Rats were assigned to one of six groups: (1) sham TBI, (2) hemorrhage only, (3) TBI only, (4) TBI plus hemorrhage and resuscitation with 0.9% saline, (5) TBI plus hemorrhage and resuscitation with hypertonic saline (7.5%), or (6) TBI plus hemorrhage and resuscitation with l-arginine (100 mg/kg) in hypertonic saline. On postinjury days 1-5, vestibulomotor function was assessed using beam balance and beam walking tasks. On postinjury days 11-15, spatial memory function was assessed using the Morris water maze. After behavioral testing, neuronal counting was performed bilaterally on specific hippocampal regions. RESULTS: : Groups receiving hypertonic saline (P < 0.05, day 15 vs. day 11) or hypertonic l-arginine (P < 0.05, days 13-15 vs. day 11) showed improved performance over time on the Morris water maze, as well as significantly improved neuronal survival in the contralateral hippocampus (P < 0.05, hypertonic saline or hypertonic l-arginine vs. normal saline) compared with untreated TBI or normal saline-treated TBI plus hemorrhage groups. CONCLUSIONS: : Hypertonic saline and hypertonic l-arginine were both effective at promoting long-term neuronal survival and behavioral recovery. The slightly earlier improvement in Morris water maze performance in the hypertonic l-arginine group warrants further studies to determine whether higher doses of l-arginine provide additional improvement. This study supports the therapeutic benefits of hypertonic resuscitation after TBI plus hemorrhagic hypotension.

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The authors have previously identified and characterized lcs, a gene encoding laccase in the white-rot basidiomycete Ceriporiopsis subvermispora. In this work, the effect of Mn2+ in the production of extracellular laccase in liquid cultures of this fungus has been assessed. It was observed that at low (0-10 microM) concentrations of Mn2+, high titers of lcs-mRNA were obtained, whereas at high (160-194 microM) concentrations of this metal ion, transcripts levels decreased markedly. This phenomenon was observed at different days of growth. On the other hand, Cu2+ or Ag+, but not Zn2+ or Cd2+, led to an accumulation of lcs transcripts only in cultures grown in the absence of Mn2+. A dramatic increase in lcs transcript levels was also obtained with syringic acid, a lignin-related aromatic compound. This effect was more pronounced in cultures lacking Mn2+. In the course of these studies it was observed that Mn2+ stimulates mycelium growth. Thus, although extracellular laccase activity appeared higher in cultures containing 160 or 194 microM Mn2+, i.e. when lcs transcripts were lower, a correlation between lcs-mRNA levels and enzymatic activity was observed when values of the latter were corrected by the amount of mycelium present in the cultures.

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