Health mediation does not reduce the readmission rate of frequent users of emergency departments living in precarious conditions: what lessons can be learned from this randomised controlled trial?

BACKGROUND: Severe overcrowding of emergency departments (EDs) affects the quality of healthcare. One factor of overcrowding is precariousness, but it has rarely been considered a key factor in designing interventions to improve ED care. Health mediation (HM) aims to facilitate access to rights, prevention, and care for the most vulnerable persons and to raise awareness among healthcare providers about obstacles in accessing healthcare. The primary aim was to determine whether HM intervention for frequent users of EDs (FUED) living in precarious conditions could reduce the readmission rate at 90 days. METHODS: Between February 2019 and May 2022, we enrolled and interviewed 726 FUED in four EDs of southeastern France in this randomised controlled trial. The HM intervention started in the ED and lasted 90 days. In addition to the primary endpoint (first readmission at 90 days), secondary endpoints (readmission at 30 and 180 days, number of hospitalisations at 30, 90, 180 days, admissions for the same reasons as the first admission) were also studied. The outcomes were measured in the ED information systems. Statistical methods included an intention-to-treat analysis and a per-protocol analysis. Comparisons were adjusted for gender, age, ED, and health mediator. RESULTS: 46% of patients reported attending the ED because they felt their life was in danger, and 42% had been referred to the ED by the emergency medical dispatch centre or their GP; 40% of patients were considered to be in a serious condition by ED physicians. The proportion of patients who were readmitted at 90 days was high but did not differ between the control and the HM intervention groups (31.7% vs. 36.3%, p = 0.23). There was no significant difference in any of the secondary outcome measures between the control and HM intervention groups. Per-protocol analysis also showed no significant difference for the primary and secondary endpoints. CONCLUSIONS: This randomised controlled trial did not show that our health mediation intervention was effective in reducing the use of emergency services by FUED living in precarious conditions. Some limitations are discussed: the duration of the intervention (90 days), the long-term effects (> 6 months), the involvement of the ED staff. TRIAL REGISTRATION: Registered on clinicaltrials.gov as NCT03660215 on 4th September 2018.

Genetic diversity and virulence of phytopathogenic Burkholderia glumae strains isolated from rice cultivars in valleys of the high jungle of Peru.

Burkholderia glumae causes bacterial leaf blight in rice, and its global spread has been exacerbated by climate change. To understand the genetic diversity and virulence of B. glumae strains isolated from rice cultivars in Peru, 47 isolates were obtained from infected rice fields, all belonging to B. glumae, and confirmed by recA and toxB sequences. The BOX-PCR typing group 38 genomic profiles, and these turn into 7 Variable Number Tandem Repeats (VNTR) haplotypes. There was no correlation between clustering and geographical origin. Nineteen strains were selected for phenotypic characterization and virulence, using both the maceration level of the onion bulb proxy and inoculation of seeds of two rice cultivars. Several strains produced pigments other than toxoflavin, which correlated with onion bulb maceration. In terms of virulence at the seed level, all strains produced inhibition at the root and coleoptile level, but the severity of symptoms varied significantly between strains, revealing significant differences in pathogenicity. There is no correlation between maceration and virulence scores, probably reflecting different virulence mechanisms depending on the host infection stage. This is the first study to evaluate the VNTR diversity and virulence of Peruvian strains of B. glumae in two commercial cultivars.

Dynamic Expression of Follicle-Stimulating Hormone and Estrogen mRNA Receptors Associated with microRNAs 34a and -let-7c in Canine Follicles during the Estrous Cycle.

The genes encoding for estrogen receptor (ESR2) and follicle-stimulating hormone receptor (FSHR) play crucial roles in ovarian follicular development. This study aimed to determine the expression levels of miRNAs predicted against FSHR and ESR2 mRNAs in follicular cells related to their target genes during the estrous cycle in canines. Antral follicles were dissected from 72 ovaries following ovariohysterectomies. MiRNAs regulating FSHR and ESR2 genes were selected from miRNA databases, and mature miRNA and mRNA expression profiling was performed using real-time polymerase chain reaction (PCR). The best miRNA for each target gene was selected considering the quantitative PCR (qPCR) performance and target prediction probability, selecting only miRNAs with a binding p-value of 1.0, and choosing cfa-miR-34a and cfa-let-7c for FSHR and ESR2, respectively. The expression levels comparing the different phases of the estrous cycle were evaluated using ANOVA. Pearson correlations between the expression pattern of each miRNA and their target genes were performed. Each miRNA and its target genes were expressed in the granulosa cells in all estrous phases. FSHR remained low in anestrus and proestrus, increased (p < 0.05) to the highest level in estrus, and decreased (p < 0.05) in diestrus. ESR2 showed the same trend as FSHR, with the highest (p < 0.05) expression in estrus and the lowest (p < 0.05) in anestrus and proestrus. A tendency for an inverse relationship was observed between the expression of miR-34a and FSHR only in the anestrus phase, while an inverse correlation (r = -0.8) was found between miRNA-7c and ESR2 (p < 0.01). The expression profile of miR-34a and miR-let-7c and their predicted target genes of dog ovarian follicles throughout the estrous cycle observed in this study suggest a role in the transcriptional regulation of FSHR and ESR2, which is the first evidence of the involvement of these miRNAs in the canine follicular function.

Rhenium-Based Electrocatalysts for Water Splitting.

Due to the contamination and global warming problems, it is necessary to search for alternative environmentally friendly energy sources. In this area, hydrogen is a promising alternative. Hydrogen is even more promising, when it is obtained through water electrolysis operated with renewable energy sources. Among the possible devices to perform electrolysis, proton exchange membrane (PEM) electrolyzers appear as the most promising commercial systems for hydrogen production in the coming years. However, their massification is affected by the noble metals used as electrocatalysts in their electrodes, with high commercial value: Pt at the cathode where the hydrogen evolution reaction occurs (HER) and Ru/Ir at the anode where the oxygen evolution reaction (OER) happens. Therefore, to take full advantage of the PEM technology for green H2 production and build up a mature PEM market, it is imperative to search for more abundant, cheaper, and stable catalysts, reaching the highest possible activities at the lowest overpotential with the longest stability under the harsh acidic conditions of a PEM. In the search for new electrocatalysts and considering the predictions of a Trasatti volcano plot, rhenium appears to be a promising candidate for HER in acidic media. At the same time, recent studies provide evidence of its potential as an OER catalyst. However, some of these reports have focused on chemical and photochemical water splitting and have not always considered acidic media. This review summarizes rhenium-based electrocatalysts for water splitting under acidic conditions: i.e., potential candidates as cathode materials. In the various sections, we review the mechanism concepts of electrocatalysis, evaluation methods, and the different rhenium-based materials applied for the HER in acidic media. As rhenium is less common for the OER, we included a section about its use in chemical and photochemical water oxidation and as an electrocatalyst under basic conditions. Finally, concluding remarks and perspectives are given about rhenium for water splitting.

Número de comidas al día durante la COVID-19 en Colombia, pobreza y mortalidad por deficiencias y anemias nutricionales / Number of meals per day during the COVID-19 in Colombia, poverty and mortality due to nutritional deficiencies and anemias

Fundamentos: Durante la pandemia por COVID–19 en Colombia en el año 2021, se han reportaron cambiosen el número de comidas consumidas al día en los hogares, lo cual ameritó un análisis de la relación entre estasituación con variables socioeconómicas territoriales y de mortalidad por deficiencias y anemias nutricionales.Métodos: Se llevó a cabo un estudio descriptivo de grupos múltiples.Resultados: A partir de los análisis se identificó una correlación moderada negativa y significativa entre elconsumo de por lo menos tres comidas al día y, la mortalidad por deficiencias y anemias nutricionales, así comopara un mayor nivel de pobreza multidimensional a nivel territorial.Conclusiones: Se identificaron factores de riesgo poblacionales como los mayores niveles de pobrezamultidimensional que pueden conducir a la utilización de estrategias de supervivencia como el consumo demenores comidas al día por la población, incidiendo en mayores altas tasas de mortalidad por deficiencias yanemias nutricionales, durante la pandemia por COVID- 19 en Colombia. (AU)

Background: During the COVID - 19 pandemic in Colombia in the year 2021, changes have been reported inthe number of meals consumed per day in households, which merited an analysis of the relationship betweenthis situation with territorial socioeconomic variables and mortality due to nutritional deficiencies and anemias.Methods: A multiple-group descriptive study was carried out.Results: From the analyses, a moderate negative and significant correlation was identified between theconsumption of at least three meals a day and mortality due to nutritional deficiencies and anemias, as well asfor a higher level of multidimensional poverty at territorial level.Conclusions: Population risk factors were identified, such as higher levels of multidimensional poverty thatmay lead to the use of survival strategies such as the consumption of fewer meals per day by the population,which may have an impact on higher mortality rates due to nutritional deficiencies and anemias during theCOVID- 19 pandemic in Colombia. (AU)

Epigenetics in drug disposition & drug therapy: symposium report of the 24th North American meeting of the International Society for the Study of Xenobiotics (ISSX).

The 24th North American International Society for the Study of Xenobiotics (ISSX) meeting, held virtually from September 13 to 17, 2021, embraced the theme of "Broadening Our Horizons." This reinforces a key mission of ISSX: striving to share innovative science related to drug discovery and development. Session speakers and the ISSX New Investigators Group, which supports the scientific and professional development of student and early career ISSX members, elected to highlight the scientific content presented during the captivating session titled, "Epigenetics in Drug Disposition & Drug Therapy." The impact genetic variation has on drug response is well established; however, this session underscored the importance of investigating the role of epigenetics in drug disposition and drug discovery. Session speakers, Drs. Ning, McClay, and Lazarus, detailed mechanisms by which epigenetic players including long non-coding RNA (lncRNAs), microRNA (miRNAs), DNA methylation, and histone acetylation can alter the expression of genes involved in pharmacokinetics, pharmacodynamics, and toxicity. Dr. Ning detailed current knowledge about miRNAs and lncRNAs and the mechanisms by which they can affect the expression of drug metabolizing enzymes (DMEs) and nuclear receptors. Dr. Lazarus discussed the potential role of miRNAs on UDP-glucuronosyltransferase (UGT) expression and activity. Dr. McClay provided evidence that aging alters methylation and acetylation of DMEs in the liver, affecting gene expression and activity. These topics, compiled by the symposium organizers, presenters, and the ISSX New Investigators Group, are herein discussed, along with exciting future perspectives for epigenetics in drug disposition and drug discovery research.

Voluntary vs forced physical activity, which is more effective in reducing body weight gain from sucrose consumption?

ABSTRACT The organoleptic characteristics of sucrose encourage its consumption in excessive amounts that result in increased body weight and possible involvement of other health indicators. In contrast, physical activity reduces body weight and promotes health and well-being, however the question remains as to what type of physical activity is the most effective to achieve those goals. The objective of the current study was to compare the effect of voluntary (VA) vs forced physical activity (FA) on body weight in organisms that consume sucrose daily. Twenty, three-month-old Wistar female rats were assigned either VA or FA; both groups were exposed to beverages with 8% sucrose concentration. The results showed that consuming sucrose daily increased body weight, despite being an active organism. However, this increase was by 11% in the VA group and 8.4% among the FA group. Therefore, although neither type of physical activity proposed in this study was effective to reduce body weight, FA influenced body weight gain less. Another interesting result was that VA registered a greater effect by reducing the consumption of sucrose. In conclusion, performing physical activity delays, but does not reverse, body weight gain from sucrose consumption.

RESUMEN Las características organolépticas de la sacarosa incentivan su consumo en cantidades excesivas que tienen como resultado el incremento del peso corporal y la posible afectación de otros indicadores de salud. En contraparte, la realización de actividad física reduce el peso corporal y favorece la salud y bienestar, pero ¿cuál es la manera más efectiva de realizar actividad física para lograr esos objetivos? Se planteó como objetivo comparar el efecto de la actividad física voluntaria (AV) contra el de la actividad física forzada (AF) sobre el peso corporal en organismos que consumen diariamente sacarosa. Se utilizaron veinte ratas hembras de la cepa Wistar de tres meses de edad, agrupadas en: (1) actividad voluntaria; (2) actividad forzada. Ambos expuestos a una bebida al 8% de concentración de sacarosa. Los resultados mostraron que consumir sacarosa diariamente incrementa el peso corporal, a pesar de ser un organismo activo. Sin embargo, este aumento fue en un 11% en AV y del 8.4% en AF. Por lo que, si bien ningún tipo de actividad física propuesto en este estudio fue efectivo para reducir el peso corporal, realizar actividad física de forma forzada influye en que la ganancia de el peso corporal sea menor. Otro resultado de interés, fue que realizar actividad física voluntaria registró un mayor efecto al reducir el consumo de sacarosa. En conclusión, realizar actividad fisica retrasa, pero no revierte la ganancia de peso corporal ante el consumo de sacarosa.

Magnetic hydrophobic solids prepared from Pickering emulsions for the extraction of polycyclic aromatic hydrocarbons from chamomile tea.

Two types of magnetic hydrophobic solids were prepared by Pickering emulsion photopolymerization using polystyrene-modified magnetic nanoparticles (PS-MNPs) as emulsion stabilizers. Additionally, PS-MNPs provided magnetic character to the final solids. W/O Pickering emulsions were produced with high amounts of oily phase (above 50 wt%), while O/W Pickering emulsions were formed with higher amounts of aqueous phase (above 60 wt%). These two types of emulsions led to two kind of solids with very different structures despite being formed by the same components. In this way, W/O Pickering emulsions produced monolithic solids, while O/W Pickering emulsions formed magnetic microparticles. Multi-walled carbon nanotubes (MWCNTs) were also added to the emulsions to provide higher hydrophobic character to the final solids. The structure and morphology of both magnetic solids containing the MWCNTs was characterized by scanning electron microscopy (SEM). Finally, their extraction efficiency was evaluated using polycyclic aromatic hydrocarbons (PAHs) as target analytes, both qualitatively (visually by the fluorescence emitted before and after the extraction) and quantitatively (using gas chromatography coupled to mass spectrometry). Therefore, the LODs ranged from 1 to 4 µg L-1 and the LOQs were between 3 and 12 µg L-1. The reproducibility of the extraction procedure with different batches of emulsions was acceptable with RSD values <13%. Finally, a recovery study was carried out in complex matrices such as chamomile tea, obtaining excellent recovery values which ranged from 99 to 108%.

Altered Metabolism of Polycyclic Aromatic Hydrocarbons by UDP-Glycosyltransferase 3A2 Missense Variants.

The UDP-glycosyltransferase (UGT) family of enzymes are important in the metabolism of a variety of exogenous substances including polycyclic aromatic hydrocarbons (PAHs), a potent class of environmental carcinogens. As compared to the majority of UGT enzymes, which utilize UDP-glucuronic acid as a cosubstrate, UGT3A2 utilizes alternative cosubstrates (UDP-glucose and UDP-xylose). UGT3A2 is expressed in aerodigestive tract tissues and was highly active against multiple PAHs with both cosubstrates. The goal of the present study was to assess the functional effects of UGT3A2 missense variants (MAF ≥ 0.005) on PAH metabolism and the utilization of cosubstrates. The glycosylation activity (Vmax/Km) of all variants against simple PAHs using both cosubstrates was significantly (P < 0.05) decreased by 42-100% when compared to wild-type UGT3A2. When utilizing UDP-glucose, the variant isoforms exhibited up to a 362-fold decrease in Vmax/Km when compared to wild-type UGT3A2, with a 3.1- to 14-fold decrease for D140N, A344T, and S435Y, a 24- and 43-fold decrease for A436T and R445C, respectively, and a 147- and 362-fold decrease for Y474C and Y74N, respectively. When utilizing UDP-xylose, the variants exhibited up to a 4.0-fold decrease in Vmax/Km when compared to wild-type UGT3A2; Y74N did not exhibit activity, and Y474C did not reach saturation (Km > 4000 µM). Additionally, both wild-type and variant UGT3A2 exhibited a significant (P < 0.05) difference in their utilization of UDP-glucose vs UDP-xylose as cosubstrates using 1-OH-pyrene as substrate. These data suggest that UGT3A2 missense variants decrease the detoxification of PAHs, potentially resulting in altered individual risk for PAH-related cancers.

Preparation, characterization and evaluation of hydrophilic polymers containing magnetic nanoparticles and amine-modified carbon nanotubes for the determination of anti-inflammatory drugs in urine samples.

Hydrophilic solids based on poly(2-hydroxyethyl methacrylate) (pHEMA) with embedded magnetic nanoparticles and amine-modified carbon nanotubes were synthesized by photopolymerization. For this purpose, an oil in water (O/W) emulsion with an aqueous/oil ratio of 60/40 was prepared where the polymerization reaction occurred in the aqueous phase due to the hydrophilicity of pHEMA and the selected nanoparticles. Variables affecting the stability and emulsion formation as well as the initiation and propagation of the polymerization were studied. The morphology of the obtained magnetic solids was characterized by SEM/EDAX in order to show the differences in presence and absence of nanoparticles within the structure. Finally, the synergic effect of both magnetic and carbon nanoparticles in the sorbent capacity of the final hydrophilic solids was evaluated through the determination of non-steroidal anti-inflammatory drugs (NSAIDs) in human urine samples. HPLC-UV was used as instrumental technique and detection limits ranged from 5 to 10 µg L-1. The precision was calculated both intra- and inter-solids (same and different synthesis batches) obtaining satisfactory RSD values of less than 13%, which indicated the robustness of the synthesis and the extraction procedure. Finally, a study with real and fortified urine samples was also carried out obtaining recovery values between 86% and 109% for target NSAIDs.

UDP-Glycosyltransferase 3A Metabolism of Polycyclic Aromatic Hydrocarbons: Potential Importance in Aerodigestive Tract Tissues.

Polycyclic aromatic hydrocarbons (PAHs) are potent carcinogens and are a primary risk factor for the development of lung and other aerodigestive tract cancers in smokers. The detoxification of PAHs by glucuronidation is well-characterized for the UDP-glycosyltransferase (UGT) 1A, 2A, and 2B subfamilies; however, the role of the UGT3A subfamily in PAH metabolism remains poorly understood. UGT3A enzymes are functionally distinct from other UGT subfamilies (which use UDP-glucuronic acid as a cosubstrate) due to their utilization of alternative cosubstrates (UDP-N-acetylglucosamine for UGT3A1, and UDP-glucose and UDP-xylose for UGT3A2). The goal of the present study was to characterize UGT3A glycosylation activity against PAHs and examine their expression in human aerodigestive tract tissues. In vitro metabolism assays using UGT3A2-overexpressing cell microsomes indicated that UGT3A2 exhibits glycosylation activity against all of the simple and complex PAHs tested. The V max/K m ratios for UGT3A2 activity with UDP-xylose versus UDP-glucose as the cosubstrate ranged from 0.65 to 4.4 for all PAHs tested, demonstrating that PAH glycosylation may be occurring at rates up to 4.4-fold higher with UDP-xylose than with UDP-glucose. Limited glycosylation activity was observed against PAHs with UGT3A1-overexpressing cell microsomes. While UGT3A2 exhibited low levels of hepatic expression, it was shown by western blot analysis to be widely expressed in aerodigestive tract tissues. Conversely, UGT3A1 exhibited the highest expression in liver with lower expression in aerodigestive tract tissues. These data suggest that UGT3A2 plays an important role in the detoxification of PAHs in aerodigestive tract tissues, and that there may be cosubstrate-dependent differences in the detoxification of PAHs by UGT3A2. SIGNIFICANCE STATEMENT: UGT3A2 is highly active against PAHs with either UDP-glucose or UDP-xylose as a cosubstrate. UGT3A1 exhibited low levels of activity against PAHs. UGT3A1 is highly expressed in liver while UGT3A2 is well expressed in extrahepatic tissues. UGT3A2 may be an important detoxifier of PAHs in humans.

Testosterone and cortisol modulate the effects of empathy on aggression in children.

This study aimed to analyze the potential moderating role of circulating testosterone, cortisol and estradiol levels on the attenuating effect of empathy on aggression in children. Participants were 139 children (80 boys and 59 girls) from the 3rd year of primary school (age 8). Their aggressive behavior was measured by the Direct and Indirect Aggression Scale, an instrument which uses peer rating; empathy was measured using the Empathy Quotient-Child Version. Hormone levels (testosterone, cortisol and estradiol) were analyzed using an enzymoimmunoassay technique in saliva samples. A regression analysis revealed an interaction effect of empathy x testosterone in girls, with higher levels of empathy corresponding to lower levels of aggression at both moderate and low testosterone levels. In boys, an interaction effect of empathy x cortisol was observed, with lower levels of empathy corresponding to higher aggression levels at moderate and high cortisol levels, and higher levels of empathy corresponding to lower aggression levels again at moderate and high cortisol levels. Our results indicate the importance of taking the interaction of psychological and biological factors into account in order to gain greater insight into the complex mechanisms underlying aggressive behavior.

Developmental trajectories of aggressive behavior in children from ages 8 to 10: The role of sex and hormones.

OBJECTIVES: This study explored the developmental trajectory of aggressive behavior from age 8 to age 10 in school-aged children, taking into account possible sex differences, as well as the involvement of certain hormones. METHODS: Participants were 90 children (49 boys and 41 girls) from four schools. At the beginning of the study, the children were 8-year old and were in 3rd grade of primary school. The second data collection phase was carried out two years later (at age 10) when the children were in 5th grade (primary). Their aggressive behavior was measured by the Direct and Indirect Aggression Scale, an instrument which uses peer rating. Hormone levels, testosterone, cortisol and estradiol were analyzed using an enzymoimmunoassay technique in saliva samples. RESULTS: The results revealed a difference in aggressive behavior between the ages of 8 and 10, in boys only, who were found to be more aggressive at age 10. A regression analysis revealed that cortisol and estradiol contributed to explaining the changes observed in aggressive behavior in boys. Boys whose cortisol levels rose most between the ages of 8 and 10 were also those whose aggressive behavior increased most during the same timeframe. Moreover, boys whose estradiol levels rose most between the ages of 8 and 10 were also those whose aggressive behavior decreased most during the same timeframe. CONCLUSIONS: Our results highlight the importance of studying aggressive behavior from a longitudinal perspective, taking into account sex differences and biological measures.

Milk Thistle Constituents Inhibit Raloxifene Intestinal Glucuronidation: A Potential Clinically Relevant Natural Product-Drug Interaction.

Women at high risk of developing breast cancer are prescribed selective estrogen response modulators, including raloxifene, as chemoprevention. Patients often seek complementary and alternative treatment modalities, including herbal products, to supplement prescribed medications. Milk thistle preparations, including silibinin and silymarin, are top-selling herbal products that may be consumed by women taking raloxifene, which undergoes extensive first-pass glucuronidation in the intestine. Key constituents in milk thistle, flavonolignans, were previously shown to be potent inhibitors of intestinal UDP-glucuronosyl transferases (UGTs), with IC50s ≤ 10 µM. Taken together, milk thistle preparations may perpetrate unwanted interactions with raloxifene. The objective of this work was to evaluate the inhibitory effects of individual milk thistle constituents on the intestinal glucuronidation of raloxifene using human intestinal microsomes and human embryonic kidney cell lysates overexpressing UGT1A1, UGT1A8, and UGT1A10, isoforms highly expressed in the intestine that are critical to raloxifene clearance. The flavonolignans silybin A and silybin B were potent inhibitors of both raloxifene 4'- and 6-glucuronidation in all enzyme systems. The Kis (human intestinal microsomes, 27-66 µM; UGT1A1, 3.2-8.3 µM; UGT1A8, 19-73 µM; and UGT1A10, 65-120 µM) encompassed reported intestinal tissue concentrations (20-310 µM), prompting prediction of clinical interaction risk using a mechanistic static model. Silibinin and silymarin were predicted to increase raloxifene systemic exposure by 4- to 5-fold, indicating high interaction risk that merits further evaluation. This systematic investigation of the potential interaction between a widely used herbal product and chemopreventive agent underscores the importance of understanding natural product-drug interactions in the context of cancer prevention.

Parenting styles and hormone levels as predictors of physical and indirect aggression in boys and girls.

This study examines the relationship between parenting style, androgen levels, and measures of physical and indirect aggression. Peer ratings of aggression were obtained from 159 eight-year-old children (89 boys and 70 girls). Parenting styles (authoritative, authoritarian or permissive) were assessed using the Parenting Styles and Dimensions Questionnaire (PSDQ).Saliva samples were obtained from children and assayed for testosterone and androstenedione concentrations. A regression analysis revealed that high testosterone levels were associated with a higher level of physical aggression in boys with authoritarian mothers. Testosterone was also found to moderate the relationship between father's authoritarian parenting and physical aggression in girls, with both moderate and high levels being significant. In relation to indirect aggression, moderate and high levels of testosterone were associated with higher levels of this type of aggression in girls with permissive mothers. Our results highlight the importance of taking into account the interaction of biological and psychosocial variables when investigating aggressive behavior.

Revisión del papel de los oligosacáridos prebióticos en la prevención de infecciones gastrointestinales: [revisión] / Role of prebiotic oligosaccharides in prevention of gastrointestinal infections: [review]

Las enfermedades gastrointestinales siguen siendo un problema de salud pública mundial. El avance de la ciencia muestra que cambios en el balance adecuado de la microflora intestinal (MI) juegan un papel crucial en la patogénesis. La evidencia apunta a que una manera de modular esta MI es a través del uso de oligosacáridos prebióticos, que estimulan el crecimiento de bacterias benéficas y que a la vez aumentan la resistencia a la invasión por patógenos. Estudios con animales indican que el consumo de carbohidratos prebióticos podría estar implicado en la prevención y tratamiento de diarreas. En infantes humanos sanos, los estudios revelan que el consumo de mezclas de prebióticas (galactooligosacáridos/fructooligosacáridos, inulina/galactooligosacáridos) disminuyen la incidencia de fiebre, de infecciones y de patógenos gastrointestinales. Lo anterior representa un gran potencial para los alimentos funcionales que los contienen, principalmente las fórmulas infantiles. Sin embargo, los estudios de prevención de diarreas mediante el suministro de prebióticos en personas con una microflora intestinal alterada no son concluyentes, sobre todo aquellos practicados en ancianos, personas con problemas crónicos de inflamación intestinal y personas con diarreas asociadas a la toma de antibióticos. Lo anterior nos indica la necesidad de estudios bioquímicos y microbiológicos más profundos en humanos de diferentes edades y condiciones de salud intestinal, a fin de determinar en que condiciones, los prebióticos tienen algún efecto sobre las infecciones.

Gastrointestinal disorders are still a main world public health problem. Scientific progress shows that and inadequate balance in intestinal microbiota (IM) plays a crucial role in its pathogenesis. Evidence indicates that one way to modulate the IM is through the use of prebiotics. These oligosaccharides stimulate the growth of benefic bacteria and increase the resistance to invading pathogens. Research using animals show that the consumption of prebiotics could be implicated in prevention and treatment of diarrhea. Studies in healthy infants also indicate that the consumption of prebiotic mixtures (galactooligosaccharides/ fructooligosaccharides, inulin/ galactooligosaccharides) decreases the incidence of fever, infections and pathogens. These results represent a great potential for functional foods that contain prebiotics, mainly the infant formulas. However, results of other clinical studies for prebiotics effects on diarrhea are not conclusive. Specially those studies that include patients with an altered IM (like the elderly), patients with chronic intestinal inflammation and with diarrhea associated to antibiotic treatments. There is a need for more biochemical and microbiological studies in humans at different ages and intestinal health conditions, in order to determine when prebiotics may effectively function on infections.

[Role of prebiotic oligosaccharides in prevention of gastrointestinal infections: a review]. / Revisión del papel de los oligosacáridos prebióticos en la prevención de infecciones gastrointestinales.

Gastrointestinal disorders are still a main world public health problem. Scientific progress shows that and inadequate balance in intestinal microbiota (IM) plays a crucial role in its pathogenesis. Evidence indicates that one way to modulate the IM is through the use of prebiotics. These oligosaccharides stimulate the growth of benefic bacteria and increase the resistance to invading pathogens. Research using animals show that the consumption of prebiotics could be implicated in prevention and treatment of diarrhea. Studies in healthy infants also indicate that the consumption of prebiotic mixtures (galactooligosaccharides/fructooligosaccharides, inulin/galactooligosaccharides) decreases the incidence of fever, infections and pathogens. These results represent a great potential for functional foods that contain prebiotics, mainly the infant formulas. However, results of other clinical studies for prebiotics effects on diarrhea are not conclusive. Specially those studies that include patients with an altered IM (like the elderly), patients with chronic intestinal inflammation and with diarrhea associated to antibiotic treatments. There is a need for more biochemical and microbiological studies in humans at different ages and intestinal health conditions, in order to determine when prebiotics may effectively function on infections.

Determination of 2-isopropyl thioxanthone and 2-ethylhexyl-4-dimethylaminobenzoate in milk: comparison of gas and liquid chromatography with mass spectrometry.

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) have been compared for the analysis of 2-isopropyl thioxanthone (ITX) and 2-ethylhexyl-4-dimethylaminobenzoate (EHDAB). Pressurized liquid extraction (PLE) was applied for the extraction of ITX and EHDAB from milk and milk-based beverages. Samples were homogenized with sea sand and anhydrous sodium sulfate, and were extracted with ethyl acetate at 100 degrees C and 10.3 x 10(6) Pa in one cycle of 10 min at 90% flush. Both, GC-MS and LC-MS/MS were suitable to determine these photoinitiators in the PLE extracts, providing appropriate identification and quantification. The recoveries obtained ranged from 70 to 99% for ITX and from 70 to 95% for EHDAB. These recoveries were equal as those obtained by a conventional liquid-liquid partitioning with acetonitrile and tert-butyl methyl ether-hexane. The quantification limits using GC-MS, based on a signal-to-noise ratio of 10, were 0.5 microg/L for ITX and 1 microg/L for EHDAB. The repeatability of the method, as indicated by the relative standard deviations, was within the range 0.9-16.1%. The same parameters calculated using LC-MS/MS result in quantification limits of 0.1 microg/L for ITX and 0.02 microg/L for EHDAB and repeatability within the range 5.2-19.4%. These results pointed out that both techniques are appropriate to determine these compounds in food samples. The method was applied to milk and milk-based beverages from different supermarkets. The ITX and EHDAB contents ranged from 2.5 to 325 microg/L and from 8 to 126 microg/L, respectively.

Allozymic variation and differentiation in the chilean blue mussel, Mytilus chilensis, along its natural distribution

Genetic differentiation in the Chilean blue mussel Mytilus chilensis (Hupé 1854) was investigated based on the variation in the allozyme frequencies of Pgm, Gpi, Icd, Me, Gsr, Lap and Pep in eight samples collected along 1800 km from Arauco (VIII Region) to Punta Arenas (XII Region). Despite the large geographic separations, values of Neis unbiased genetic distance, D (0.004-0.048) and standardised genetic variation among populations, Fst (0.011-0.055) were small. The levels of gene flow (Nm = 8) found in this study prevent the effect of differentiation among populations by genetic drift. This findings indicate that its long-lived planktotrophic larvae provides this species with considerable dispersal ability throughout its range which is favoured by the ocean currents along the chilean coast. In terms of management of the M. chilensis fishery, the results provide no evidence for discrete stocks, with the possible exception of the Punta Arenas population. Considering the intensive aquaculture activities with this species the present study provide preliminary data which can be used as a baseline for further characterization and /or monitoring these mussel populations.