Evaluation of the survival of homofermentative Lacticaseibacillus casei subsp. casei in fermented milk matrix enriched with non-digestible natural fibers.

The physicochemical changes induced by seven different dietary fibers (oat, bamboo, pea, inulin, apple, potato, and wheat) during storage and their effects on the survival of homofermentative Lacticaseibacillus casei subsp. casei (L. casei) in fermented milk matrix were analyzed. For this, an experimental study of the effect of storage time on the microorganisms count and physicochemical properties (pH, titratable acidity, syneresis and viscosity) of milk fermented with L. casei was carried out every two weeks during a storage period of 42 days. Throughout the period studied at 4 °C, no significant differences were found in terms of viscosity values, syneresis rates and L. casei counts, despite the substantial decrease in the pH values. Notably, the substantial increase in the concentration of free hydronium ions (active acidity) in the fiber-enriched matrices during the follow-up period was positively correlated with the L.casei survival. The microbial count determined in all samples was higher than 1 × 107 CFU/g, the minimum value recommended by world organizations for nutraceutical fermented foods. Consequently, the studied prebiotic fibers could be considered in the production of new fermented dairy products with functional properties.

Effect of Long-Term Intake of Nutritive and Non-Nutritive Sweeteners on Metabolic Health and Cognition in Adult Male Rats.

This study evaluated the effects of long-term intake of nutritive sweeteners (NSs) and non-nutritive sweeteners (NNSs) on body weight, food and energy intake, blood pressure, metabolic parameters, and memory retention in rats. Sixty male Sprague-Dawley rats were randomly divided into six groups (n = 10 per group): control (water),10% sucrose (SUC), aspartame (ASP), sucralose (SCA), stevia (STV), and 5% xylitol (XYL). Pure NSs (SUC and XYL) and NNSs were added to the drinking water for 18 weeks. ASP, SCA, and STV dosage was based on the estimated daily intake limit: 4.1, 2.0, and 3.4 mg/kg/day, respectively. Chronic access to NNSs did not result in any difference in total weight gain of the rats, while it was significantly elevated in the SUC group compared with the control and NNSs groups. Food intake was significantly lower in all NNSs groups compared with SUC and control groups. Sweetened beverage intake volumes were significantly diminished in all NNSs groups compared with intake in SUC and control groups. Total calories consumed were lower for the STV and XYL groups compared with all other groups. Blood pressure and glucose metabolism did not differ significantly between the groups. All sweeteners increased total cholesterol, low-density lipoprotein, and triglyceride levels. Short-term memory was significantly impaired in the ASP group in the novel object recognition task, while long-term memory was impaired in SUC and STV groups. These metabolic and behavioral results suggest that the long-term intake of NSs or NNSs can be associated with peripheral and central effects.

Comparative analysis of anthropometric indicators for diagnosing obesity and predicting cardiometabolic risk in Mexican adolescents.

Introduction: Introduction: obesity is a cardiometabolic risk (CMR) factor in adolescents. It represents a public health problem that requires simple diagnostic strategies based on the determination of anthropometric indicators (AIs) such as body mass index (BMI), waist circumference (WC), conicity index (CONI), waist-to-height ratio (WHtR), and body fat percentage (BFP). The purpose of the current contribution was to analyze the utility of the aforementioned AIs for evaluating obesity as a CMR factor in Mexican adolescents. Materials and methods: the design of the study is descriptive and cross-sectional. Nutritional status was established by using various AIs and as a CMR factor under the criteria of WHtR. Participating in the present investigation were 2,000 adolescents from 15 to 17 years of age, of which 1,079 (53.9 %) were female and 921 (46.1 %) were male. All were high school students in Tuxtla Gutiérrez, Chiapas, Mexico. Results and conclusion: the prevalence of obesity was influenced by gender. With the WHtR and BFP, male students exhibited a greater prevalence of obesity, while with the BMI and CONI, the percentage of obesity was similar between the two genders. BMI was significantly correlated with BFP, WC and WHtR, and was one of the AIs with the greatest area under the curve, showing a good capacity to predict cardiometabolic risk. BMI is a simple and adequate tool for diagnosing obesity and predicting CMR in adolescents.

Introducción: Introducción: la obesidad es un factor de riesgo cardiometabolico (RCM) en los adolescentes y representa un problema de salud pública que requiere estrategias diagnosticas sencillas, basadas en la determinación de indicadores antropométricos (IA) como el índice de masa corporal (IMC), la circunferencia de la cintura (CC), el índice de conicidad (ICONI), el índice de cintura-talla (ICT) y el porcentaje de grasa corporal (PGC). El propósito del presente estudio fue analizar la utilidad de diversos IA (IMC, CC, ICONI, ICT y PGC) para evaluar la obesidad como factor de RCM en adolescentes mexicanos. Materiales y métodos: el diseño del estudio fue descriptivo y transversal. Se analizó el estado nutricional mediante varios IA y el factor de RCM bajo los criterios del ICT. Este estudio fue conducido en 2000 adolescentes de entre 15 y 17 años, de los cuales 1079 (53,9 %) eran mujeres y 921 (46,1 %) varones, todos ellos estudiantes de nivel medio superior de Tuxtla Gutiérrez, Chiapas, México. Resultados y conclusión: la prevalencia de la obesidad estuvo influenciada por el género: los varones presentaron una mayor prevalencia de obesidad con ICT y PGC, mientras que con IMC e ICONI, el porcentaje de obesidad fue similar entre ambos géneros. El IMC se correlacionó significativamente con el PGC, la CC y el ICT, y fue uno de los IA con mayor área bajo la curva, mostrando una buena capacidad para predecir el RCM. El IMC representa una herramienta sencilla y adecuada para el diagnóstico de obesidad y predecir el RCM en adolescentes.

Development of in-house materials for the verification of specific gravity measurements: Homogeneity, stability, and proficiency studies.

We developed and evaluated the properties of in-house urine reference materials for the verification of laboratory refractometers, which are frequently used in clinical chemistry and doping testing laboratories. Urine was gathered from 26 healthy volunteers (16 male 30 ± 5 years old and 10 female 29 ± 4 years old), from which two urine batches were obtained: one with a low specific gravity (1.012± 0.003) and the other with a high specific gravity (1.027 ± 0.003). Homogeneity studies were conducted over 20 consecutive days. For short-term stability studies, aliquots of both urine batches were stored at -20 ± 2°C; 3 ± 2°C; 20 ± 2°C; 45 ± 2°C for 0, 2, 7, 14 and 35 days, under both light and dark conditions. Similarly, another study was conducted to measure the long-term stability of urine at -20 ± 2°C, over a 24-month evaluation period. Our data showed that the urine was homogeneous and stable at -20 ± 2°C, 3 ± 2°C, 20 ± 2°C, and 45 ± 2°C under both light and dark conditions. In all cases, the urine was evaluated by specific gravity and no statistically significant differences (p ≤ 0.05) were recorded. Additionally, a proficiency test was conducted in collaboration with 15 ISO/IEC 17025 accredited laboratories, and z-scores and performance factors were evaluated. These data indicate that this material could be used for the verification of refractometers.

Effect of bis-1,4-dihydropyridine in the kidney of diabetic rats.

The in vivo effectiveness of 4-dihydropyridine (bis-1,4-DHP), a new calcium-channel blocker, as a nephroprotector in isolated perfused kidney was evaluated by determining its effects on parameters associated with renal injury in diabetic rats. Diabetes in male Wistar rats, control, diabetic, control + bis-1,4-DHP, and diabetic + bis-1,4-DHP, was induced by a single administration of STZ (55 mg·kg(-1), i.p.). In the drug-treated groups, treatment with bis-1,4-DHP (10 mg·kg(-1)·day(-1)) started one week before diabetes induction; bis-1,4-DHP was dissolved in DMSO (0.3%) and suspended in drinking water with carboxymethyl cellulose (3%). Parameters evaluated were body weight, blood glucose, albuminuria, proteinuria, creatinine, urea excretion, kidney's weight / body weight ratio, and kidney perfusion pressure in all rat groups at different times of diabetes (2, 4, 6, and 10 weeks). Kidney weight of diabetic rats significantly increased vs. control, control + bis-1,4-DHP, and diabetic + bis-1,4-DHP rats at different times of diabetes. The ratios % kidney weight / 100 g body weight were different between control, control + bis-1,4-DHP, and diabetic + bis-1,4-DHP rats vs. diabetic rats (P < 0.05). Kidney perfusion pressure was decreased by diabetes, while it was partially recovered by bis-1,4-DHP treatment in response to phenylephrine. Bis-1,4-DHP had a tendency to decrease hyperglycemia vs. diabetic rats, even though glycemia was too high as compared with controls, and it ameliorated albuminuria, creatinine, and urea excretion, suggesting a favorable effect on renal haemodynamics. Bis-1,4-DHP, by inhibiting Ca(2+) entrance, induced vasodilation in renal vascular bed and thus may have a nephroprotective effect against diabetes-induced renal dysfunction, but does not have significant impact on hyperglycemia.