Dynamics of Gut Microbiota and Short-Chain Fatty Acids during a Cycling Grand Tour Are Related to Exercise Performance and Modulated by Dietary Intake.

BACKGROUND: Regular exercise has been described to modify both the diversity and the relative abundance of certain bacterial taxa. To our knowledge, the effect of a cycling stage race, which entails extreme physiological and metabolic demands, on the gut microbiota composition and its metabolic activity has not been analysed. OBJECTIVE: The aim of this cohort study was to analyse the dynamics of faecal microbiota composition and short-chain fatty acids (SCFAs) content of professional cyclists over a Grand Tour and their relationship with performance and dietary intake. METHODS: 16 professional cyclists competing in La Vuelta 2019 were recruited. Faecal samples were collected at four time points: the day before the first stage (A); after 9 stages (B); after 15 stages (C); and on the last stage (D). Faecal microbiota populations and SCFA content were analysed using 16S rRNA sequencing and gas chromatography, respectively. A principal component analysis (PCA) followed by Generalised Estimating Equation (GEE) models were carried out to explore the dynamics of microbiota and SCFAs and their relationship with performance. RESULTS: Bifidobacteriaceae, Coriobacteriaceae, Erysipelotrichaceae, and Sutterellaceae dynamics showed a strong final performance predictive value (r = 0.83, ranking, and r = 0.81, accumulated time). Positive correlations were observed between Coriobacteriaceae with acetate (r = 0.530) and isovalerate (r = 0.664) and between Bifidobacteriaceae with isobutyrate (r = 0.682). No relationship was observed between SCFAs and performance. The abundance of Erysipelotrichaceae at the beginning of La Vuelta was directly related to the previous intake of complex-carbohydrate-rich foods (r = 0.956), while during the competition, the abundance of Bifidobacteriaceae was negatively affected by the intake of simple carbohydrates from supplements (r = -0.650). CONCLUSIONS: An ecological perspective represents more realistically the relationship between gut microbiota composition and performance compared to single-taxon approaches. The composition and periodisation of diet and supplementation during a Grand Tour, particularly carbohydrates, could be designed to modulate gut microbiota composition to allow better performance.

Citrulline supplementation improves spatial memory in a murine model for Alzheimer's disease.

OBJECTIVES: Alzheimer's disease (AD) correlates with the dysfunction of metabolic pathways that translates into neurological symptoms. An arginine deficiency, a precursor of nitric oxide (NO), has been reported for patients with AD. We aimed to evaluate the effect of citrulline oral supplementation on cognitive decline in an AD murine model. METHODS: Three-month citrulline or water supplementation was blindly given to male and female wild-type and 3 × Tg mice with AD trained and tested in the Morris water maze. Cerebrospinal fluid and brain tissue were collected. Ultra-performance liquid chromatography was used for arginine determinations and the Griess method for NO. RESULTS: Eight-month-old male 3 × Tg mice with AD supplemented with citrulline performed significantly better in the Morris water maze task. Arginine levels increased in the cerebrospinal fluid although no changes were seen in brain tissue and only a tendency of increase of NO was observed. CONCLUSIONS: Citrulline oral administration is a viable treatment for memory improvement in the early stages of AD, pointing to NO as a viable, efficient target for memory dysfunction in AD.

Production Performance, Nutrient Digestibility, and Milk Composition of Dairy Ewes Supplemented with Crushed Sunflower Seeds and Sunflower Seed Silage in Corn Silage-Based Diets.

This study determined production performance, nutrient digestibility, and milk composition of dairy ewes supplemented with crushed sunflower seeds (Helianthus annuus) and sunflower seed silage in corn silage-based diets. Six ewes were grouped in a double 3 × 3 Latin square design with three periods of 21 days. All treatments were based on ad libitum corn silage. Control diet was based on alfalfa hay (333 g/kg DM), sorghum grain (253 g/kg DM), triticale grain (200 g/kg DM), soybean meal (167 g /kg DM), and vitamin and mineral premix (47 g/kg DM). Sunflower seeds (SF) and sunflower seed silage (SFS) treatments consisted of alfalfa hay (333 g/kg DM), sorghum grain (267 g/kg DM), triticale grain (100 g/kg DM), soybean meal (167 g /kg DM), SF or SFS (87 g/kg DM) and vitamin and mineral premix (47 g/kg DM). Compared to control, SF and SFS increased intake and digestibility of fiber components, such as neutral detergent fiber (NDF) and acid detergent fiber (ADF). Body weight, nitrogen balance, milk yield, milk fat yield, milk protein yield, lactose yield and milk urea N were similar between treatments. Overall, results demonstrated that crushed sunflower seeds and ensiled seeds do not change significantly productive parameters of dairy sheep.

Pseudomonas fluorescens: A Bioaugmentation Strategy for Oil-Contaminated and Nutrient-Poor Soil.

Bioremediation technology is one of the most profitable and sustainable strategies for remediating soils contaminated with hydrocarbons. This study focuses on assessing the influence of biostimulation and bioaugmentation with Pseudomonas fluorescens to contribute to the removal of total petroleum hydrocarbons (TPHs) of a soil. Laboratory studies were carried out (measurements of emitted CO2, surface tension, and residual TPH) to select the best bioaugmentation and biostimulation treatment. The sources of C, N, and P were glucose-yeast extract, NH4Cl-NaNO3, and K2HPO4-K3PO4, respectively. The effect of culture conditions on the reduction of TPH and respiratory activity was evaluated through a factorial design, 23, in a solid culture system. After 80 days of incubation, it was observed that treatments of yeast extract-NH4Cl-K2HPO4 (Y4) and glucose-NaNO3-K3PO4 (Y5) presented a higher level of TPH removal (20.91% and 20.00% degradation of TPH, respectively). Biostimulation favors the production of biosurfactants, indirectly measured by the change in surface tension in the soil extracts. The treatments Y4 and Y5 showed a lower change value of the surface tension (23.15 and 23.30 mN·m-1 at 25 °C). A positive correlation was determined between the change in surface tension and the removal of TPH; hence there was a contribution of the biosurfactants produced to the removal of hydrocarbons.

Dietary supplementation with hybrid palm oil alters liver function in the common Marmoset.

Hybrid palm oil, which contains higher levels of oleic acid and lower saturated fatty acids in comparison with African palm oil, has been proposed to be somehow equivalent to extra virgin olive oil. However, the biological effects of its consumption are poorly described. Here we have explored the effects of its overconsumption on lipid metabolism in a non-human primate model, the common marmoset. Dietary supplementation of marmoset with hyperlipidic diet containing hybrid palm oil for 3 months did not modify plasma lipids levels, but increased glucose levels as compared to the supplementation with African palm oil. Liver volume was unexpectedly found to be more increased in marmosets consuming hybrid palm oil than in those consuming African palm oil. Hepatic total lipid content and circulating transaminases were dramatically increased in animals consuming hybrid palm oil, as well as an increased degree of fibrosis. Analysis of liver miRNAs showed a selective modulation of certain miRNAs by hybrid palm oil, some of which were predicted to target genes involved in cell adhesion molecules and peroxisomal pathways. Our data suggest that consumption of hybrid palm oil should be monitored carefully, as its overconsumption compared to that of African palm oil could involve important alterations to hepatic metabolism.

Calciphylaxis: Beyond CKD-MBD. / Calcifilaxis: más allá de CKD-MBD.

INTRODUCTION: Calcific uraemic arteriolopathy (CUA), also called calciphylaxis, is a rare but potentially fatal vascular disorder that almost exclusively affects patients with chronic renal failure. The objective of this study was to analyse various risk factors for developing CUA and its subsequent clinical course according to the treatment received. MATERIALS AND METHODS: A retrospective study that included patients diagnosed with CUA from December 1999 to December 2015. Various risk factors, clinical course and treatment options were analysed. RESULTS: A total of 28 patients (53.6% females) with a mean age of 67.2±11.8 (38-88) years were included. At the time of diagnosis, 53.6% were on haemodialysis, 25% were kidney transplant patients and 21.4% had normal renal function. The use of steroids (100%, P=.001) was the main risk factor in renal transplant patients. Skin lesions resolved in 60.7% (especially in those receiving multitargeted therapy). Patient survival at 12 months was 29% in transplant patients, 57% in haemodialysis patients and 100% in normal renal function patients (log-rank 6.88, P=.032). Chronic renal failure (P=.03) and hypoalbuminaemia (P=.02) were the main risk factor for CUA mortality. CONCLUSIONS: Although the incidence of CUA remains low, CUA mortality is very high, Special attention to its occurrence in kidney transplant patients and «non-renal¼ CUA forms is required. Oral anticoagulants and steroids appear to be the main risk factors, CUA is a challenge; a registry of patients and determining standard therapy are required.

Hydroxytyrosol supplementation modulates the expression of miRNAs in rodents and in humans.

Dietary microRNAs (miRNAs) modulation could be important for health and wellbeing. Part of the healthful activities of polyphenols might be due to a modulation of miRNAs' expression. Among the most biologically active polyphenols, hydroxytyrosol (HT) has never been studied for its actions on miRNAs. We investigated whether HT could modulate the expression of miRNAs in vivo. We performed an unbiased intestinal miRNA screening in mice supplemented (for 8 weeks) with nutritionally relevant amounts of HT. HT modulated the expression of several miRNAs. Analysis of other tissues revealed consistent HT-induced modulation of only few miRNAs. Also, HT administration increased triglycerides levels. Acute treatment with HT and in vitro experiments provided mechanistic insights. The HT-induced expression of one miRNA was confirmed in healthy volunteers supplemented with HT in a randomized, double-blind and placebo-controlled trial. HT consumption affects specific miRNAs' expression in rodents and humans. Our findings suggest that the modulation of miRNAs' action through HT consumption might partially explain its healthful activities and might be pharmanutritionally exploited in current therapies targeting endogenous miRNAs. However, the effects of HT on triglycerides warrant further investigations.

Docosahexaenoic acid modulates the enterocyte Caco-2 cell expression of microRNAs involved in lipid metabolism.

Consumption of the long-chain ω-3 (n-3) polyunsaturated fatty acid docosahexaenoic acid (DHA) is associated with a reduced risk of cardiovascular disease and greater chemoprevention. However, the mechanisms underlying the biologic effects of DHA remain unknown. It is well known that microRNAs (miRNAs) are versatile regulators of gene expression. Therefore, we aimed to determine if the beneficial effects of DHA may be modulated in part through miRNAs. Loss of dicer 1 ribonuclease type III (DICER) in enterocyte Caco-2 cells supplemented with DHA suggested that several lipid metabolism genes are modulated by miRNAs. Analysis of miRNAs predicted to target these genes revealed several miRNA candidates that are differentially modulated by fatty acids. Among the miRNAs modulated by DHA were miR-192 and miR-30c. Overexpression of either miR-192 or miR-30c in enterocyte and hepatocyte cells suggested an effect on the expression of genes related to lipid metabolism, some of which were confirmed by endogenous inhibition of these miRNAs. Our results show in enterocytes that DHA exerts its biologic effect in part by regulating genes involved in lipid metabolism and cancer. Moreover, this response is mediated through miRNA activity. We validate novel targets of miR-30c and miR-192 related to lipid metabolism and cancer including nuclear receptor corepressor 2, isocitrate dehydrogenase 1, DICER, caveolin 1, ATP-binding cassette subfamily G (white) member 4, retinoic acid receptor ß, and others. We also present evidence that in enterocytes DHA modulates the expression of regulatory factor X6 through these miRNAs. Alteration of miRNA levels by dietary components in support of their pharmacologic modulation might be valuable in adjunct therapy for dyslipidemia and other related diseases.

Oxidative stress in rat testis and epididymis under intermittent hypobaric hypoxia: protective role of ascorbate supplementation.

Hypobaric hypoxia (HH), an environmental condition of high altitude encountered by mountaineers, miners, and observatory, rural health, border patrol, and rural education workers, jeopardizes normal physiologic functions in humans. The present study was conducted to evaluate the effects of intermittent HH (IHH; equivalent to 4600 m above mean sea level) on oxidative stress and the protective role of dietary ascorbic acid on rat testis and epididymis. Ten-week-old male Wistar rats were assigned to 1 of 6 groups: 1) normobaric (Nx), 2) Nx + physiologic solution (Nx + PS), 3) Nx + ascorbic acid (Nx + AA), 4) IHH, 5) IHH + PS, or 6) IHH + AA. Animals subjected to IHH were exposed for 96 hours followed by normobaric conditions for 96 hours for a total of 32 days. The control groups (2 and 5) were injected with doses of PS, and the treated groups (3 and 6) were injected with doses of AA (10 mg x kg(-1) body weight) at an interval of 96 hours. Rats were sacrificed on day 32 after initiation of the protocol. The testis and epididymis were collected to determine the activity and expression of glutathione reductase and the levels of lipid peroxide formation. An epididymal sperm count was also performed in each animal. The results of this study revealed that IHH induced lipid peroxidation, a reduction in glutathione reductase activity in testis and epididymis, and a significant decrease in epididymal sperm count. Treatment with AA prevented these changes. In conclusion, AA was capable of decreasing oxidative stress in testis and epididymis under IHH. This protection by AA of the IHH-induced lipid peroxidation can be explained in part by the preservation of glutathione reductase activity in these organs.

Treatment with calcimimetics in kidney transplantation.

Graft and patient survival in renal transplantation has increased with better immune suppression treatment, leading to the appearance of new complications such as posttransplant bone disease. After renal transplantation and the recovery of renal function, mineral metabolism disorders secondary to renal failure could be expected to normalize. However, both immediately after transplantation and later, and even with good renal graft function, we see bone disorders associated to renal osteodystrophy, a high incidence of osteopenia, persistent hyperparathyroidism, hypercalcemia, hypophosphoremia, and less commonly, aseptic bone necrosis. The causes potentially responsible for these disorders have basically been identified as different degrees of renal insufficiency in the graft, persistent posttransplant secondary hyperparathyroidism, and negative impact of immunosuppression treatment, particularly corticosteroids. The most important factor in the evolution of metabolic and bone disorders after renal transplantation, however, is pretransplant bone status. Special attention should be paid to other osteoarticular complications such as loss of bone mass and fractures, leading to significant morbidity. In the therapeutic approach to these patients, as well as encouraging physical exercise and advice about diet or other habits, the use of drugs such as calcium and vitamin D supplements, bisphosphonates, and more recently, calcimimetics have made significant improvements in the prevention and treatment of bone-mineral metabolism. It has been shown that calcimimetic agents can control the parathyroid hormone, reduce episodes of hypercalcemia, and improve hypophosphatemia. Their properties have to be assessed in broader studies to establish the basis for their widespread use among renal transplant recipients.

Efecto de la cafeína en el rendimiento deportivo / No disponible

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Laxantes con alto contenido en fosfatos: eficaces pero no tan seguros / Purgative with high sodium phosphate contents: efficacious but not so safe

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Food habits and nutritional status assessment of adolescent soccer players. A necessary and accurate approach.

The aim of this study was to assess the food habits and nutritional status of high level adolescent soccer players (N = 33; ages 14-16 yrs) living in their home environment. Body composition (height, mass, skinfolds), biochemical and hematological parameters, performance in soccer-specific tests (sprinting, jumping, intermittent endurance), and dietary intake (weighed food intake method) and related behaviors (nutrient supplement use, daily activity profile) were assessed. Daily energy expenditure and energy intake were 12.5 MJ and 12.6 MJ, respectively. Protein (16% of energy intake; 1.9 g/kg of body mass), lipid (38%), and cholesterol (385 mg) intake were above recommendations, while carbohydrates (45%) were below. The food intake of these adolescents was based on cereals and derivates; meat, fish, and eggs; milk and dairy products; biscuits and confectionery; and oil, butter and margarine, which provided 78% of total energy intake, 85% of proteins, 64% of carbohydrates, 90% of lipids, and 47% of fiber. Although diet provided sufficient iron, 48% of individuals showed iron deficiency without anemia. Based on these results, a well designed nutrition intervention would be advisable for optimizing performance, and especially for promoting healthy eating habits in adolescent soccer players.

Sensibilidad y especificidad del Test Aubio Dot-HIV/1-2 frente al Test de Elisa HIV/1-2 6G ABBOTT / Sensibility and specificity of the test aubio dot HIV/1-2 in front of the test of elisa HIV/1-2 6G abbott

El SIDA fue reconocida entidad clínica en 1891, su agente etiológico es un Retrovirus Humano (3), (6), (1), (2), (8). En el hombre se identificó dos variedades, el VIH-1 y el VIH2, éstos están relacionados con el retrovirus de los Simios (VIS) y retrovirus de los felinos (VIF), (3), (7), (9), (11), (20). Debemos considerar el origen de los retrovirus humanos, que corresponden a una Zoonosis, esto es una transmisión interespecie. Esta condición, nos obliga a estudiar con mucha exactitud; la sensibilidad y especificidad, de los métodos, que de acuerdo a los propósitos, que se persiguen, se usen. Al efectuar esta investigación, buscamos tener test básicos para efectuar las pruebas de tamizaje y tener así el menor porcentaje de falso positivos y menos porcentaje de falsos negativos. La especificidad consitituye uno de los parámetros más importantes que deben considerarse en los sistemas de diagnóstico para la detección de anticuerpos contra VIH (4), (5), (10). La sensibilidad y especificidad son los dos factores principales que determinan la exactitud con que una prueba permite distinguir entre las personas infectadas y las no infectadas. Una prueba de alta sensibilidad que dará pocos resultados falsos negativos. Por consiguiente, sólo se deben emplear pruebas de la más alta sensibilidad que dará pocos resultados falsos negativos (por ejemplo, para la transfusión, donación sin riesgo). En una prueba con alta especificidad serán pocos los resultados falsos positivos por lo que se le debe utilizar cuando sea necesario obtener una tas mínima de resultados falsos positivos (por ejemplo: pruebas de diagnóstico individual de infección p;or VIH)