Effects of DBD air plasma treatment on the enhancement of black gram (Vigna mungo l.) seed germination and growth.

Effects of black gram (vigna mungo L.cv. Barimash 3) seed treatments with 400 torr dielectric barrier discharge (DBD) air plasma on seed surface morphology, seed germination, seedling growth and antioxidant enzyme activities in the roots, shoots and leaves were investigated. The plasma discharge voltage, frequency, electrode spacing, gas temperature and power were 5kV, 4.5kHz, 60mm, 310K and 45W, respectively. The seeds were treated for the duration ranging from 20 to 180 s. Seed germination rate, seedling growth, total chlorophyll content, total soluble protein and sugar concentrations in the seedlings grown from the treated seeds were found to increase 13.67%, 37.13%, 37.26%,53.60% and 51.71%, respectively, with respect to control. This study reveals that the DBD air plasma was involved in the enhancement of nitrogen complex in the seed coat of black gram which upregulated the protein through nitrogen conversion that was ultimately responsible for the increased seed germination and seedling growth of black gram.

Potential of N2/O2 atmospheric pressure needle-water DC microplasmas for nitrogen fixation: nitrite-free synthesis of nitrates.

A needle-water DC microplasma system working at atmospheric pressure in N2/O2 gas mixtures is used to study the fundamental mechanisms of nitrate/nitrite synthesis in highly complex and yet little-known plasma-water systems. Plasma properties are investigated by means of optical emission spectroscopy while the activated water is analyzed following the treatment using ionic chromatography and UV-Vis absorbance spectroscopy. Experiments highlight that the energy efficiency and selectivity of the process are influenced by the oxygen content and the plasma-induced water heating, with strong differences when the water surface is the anode or the cathode electrode. Nitrates are successfully synthesized without residual nitrites in the solution with a comparatively higher energy efficiency when the water is the cathode. The possible reactions involved in the gas phase and aqueous phase chemistry are presented and future scope for the optimization of the system is discussed.

Cntnap4 differentially contributes to GABAergic and dopaminergic synaptic transmission.

Although considerable evidence suggests that the chemical synapse is a lynchpin underlying affective disorders, how molecular insults differentially affect specific synaptic connections remains poorly understood. For instance, Neurexin 1a and 2 (NRXN1 and NRXN2) and CNTNAP2 (also known as CASPR2), all members of the neurexin superfamily of transmembrane molecules, have been implicated in neuropsychiatric disorders. However, their loss leads to deficits that have been best characterized with regard to their effect on excitatory cells. Notably, other disease-associated genes such as BDNF and ERBB4 implicate specific interneuron synapses in psychiatric disorders. Consistent with this, cortical interneuron dysfunction has been linked to epilepsy, schizophrenia and autism. Using a microarray screen that focused upon synapse-associated molecules, we identified Cntnap4 (contactin associated protein-like 4, also known as Caspr4) as highly enriched in developing murine interneurons. In this study we show that Cntnap4 is localized presynaptically and its loss leads to a reduction in the output of cortical parvalbumin (PV)-positive GABAergic (γ-aminobutyric acid producing) basket cells. Paradoxically, the loss of Cntnap4 augments midbrain dopaminergic release in the nucleus accumbens. In Cntnap4 mutant mice, synaptic defects in these disease-relevant neuronal populations are mirrored by sensory-motor gating and grooming endophenotypes; these symptoms could be pharmacologically reversed, providing promise for therapeutic intervention in psychiatric disorders.

Alteration in propagating colonic contractions by dairy proteins in isolated rat large intestine.

Gastrointestinal conditions in which the transit of contents is altered may benefit from nutritional approaches to influencing health outcomes. Milk proteins modulate the transit of contents along different regions, suggesting that they have varying effects on neuromuscular function to alter gastrointestinal motility. We tested the hypothesis that bovine whey and casein milk protein hydrolysates could have direct modulatory effects on colonic motility patterns in isolated rat large intestine. Casein protein hydrolysate (CPH), whey protein concentrate (WPC), whey protein hydrolysate (WPH), and a milk protein hydrolysate (MPH; a hydrolyzed blend of 60% whey to 40% casein) were compared for their effects on spontaneous contractile waves. These contractions propagate along the length of the isolated intact large intestine (22 cm) between the proximal colon and rectum and were detected by measuring activity at 4 locations. Milk proteins were perfused through the tissue bath, and differences in contraction amplitude and frequency were quantified relative to pretreatment controls. Propagation frequency was decreased by CPH, increased by MPH, and unaffected by intact whey proteins. The reduced motility with CPH and increased motility with MPH indicate a direct action of these milk proteins on colon tissue and provide evidence for differential modulation by hydrolysate type. These findings mirror actions on lower gastrointestinal transit reported in vivo, with the exception of WPH, suggesting that other factors are required.

Maternal conjugated linoleic acid supplementation reverses high-fat diet-induced skeletal muscle atrophy and inflammation in adult male rat offspring.

A high-saturated-fat diet (HFD) during pregnancy and lactation leads to metabolic disorders in offspring concomitant with increased adiposity and a proinflammatory phenotype in later life. During the fetal period, the impact of maternal diet on skeletal muscle development is poorly described, despite this tissue exerting a major influence on life-long metabolic health. This study investigated the effect of a maternal HFD on skeletal muscle anabolic, catabolic, and inflammatory signaling in adult rat offspring. Furthermore, the actions of maternal-supplemented conjugated linoleic acid (CLA) on these measures of muscle phenotype were investigated. A purified control diet (CD; 10% kcal fat), a CD supplemented with CLA (CLA; 10% kcal fat, 1% total fat as CLA), a high-fat (HFD; 45% kcal fat from lard), or a HFD supplemented with CLA (HFCLA; 45% kcal fat from lard, 1% total fat as CLA) was fed ad libitum to female Sprague-Dawley rats for 10 days before mating and throughout gestation and lactation. Male offspring received a standard chow diet from weaning, and the gastrocnemius was collected for analysis at day 150. Offspring from HF and HFCLA mothers displayed lower muscular protein content accompanied by elevated monocyte chemotactic protein-1, IL-6, and IL-1ß concentrations. Phosphorylation of NF-κBp65 (Ser(536)) and expression of the catabolic E3 ligase muscle ring finger 1 (MuRF1) were increased in HF offspring, an effect reversed by maternal CLA supplementation. The present study demonstrates the importance of early life interventions to ameliorate the negative effects of poor maternal diet on offspring skeletal muscle development.

Seasonal and age effects on energy requirements in domestic short-hair cats (Felis catus) in a temperate environment.

There is little information known about the energy requirements of cats in temperature climates. Energy requirement of domestic short-haired cats was determined using three groups of mixed gender - old kept outside (approximately 9.9 years of age; 4.8 kg; n = 9), young kept outside (approximately 3.1 years of age; 3.9 kg; n = 8) or young kept inside (approximately 3.1 years of age; 3.9 kg; n = 8). Cats were housed individually for 5 weeks during summer (18.5 ± 0.5 °C) and winter (8.5 ± 0.4 °C) and were fed a commercially available maintenance diet ad libitum. In both periods, energy expenditure was determined from the rates of (2) H and (18) O elimination for blood H2 O over a 12 day period, from a doubly labelled water bolus (2) H2 O (0.7 g/kg BW) and H2 (18) O (0.13 g/kg BW) administered intravenously. During the summer period, macronutrient digestibility was determined. Older cats had a reduction (p < 0.05) in apparent digestibility of dry matter (approximately 9%), energy (approximately 8%) and protein (6%). There was a significant effect of age and season on energy intake and energy expenditure. While lean mass was affected by age and season, there was no effect of age or season on energy expenditure when expressed as a proportion of lean mass. Possible seasonal differences in nutrient digestibility may explain these results.

Anisotropic nutrient transport in three-dimensional single species bacterial biofilms.

The ability for a biofilm to grow and function is critically dependent on the nutrient availability, and this in turn is dependent on the structure of the biofilm. This relationship is therefore an important factor influencing biofilm maturation. Nutrient transport in bacterial biofilms is complex; however, mathematical models that describe the transport of particles within biofilms have made three simplifying assumptions: the effective diffusion coefficient (EDC) is constant, the EDC is that of water, and/or the EDC is isotropic. Using a Monte Carlo simulation, we determined the EDC, both parallel to and perpendicular to the substratum, within 131 real, single species, three-dimensional biofilms that were constructed from confocal laser scanning microscopy images. Our study showed that diffusion within bacterial biofilms was anisotropic and depth dependent. The heterogeneous distribution of bacteria varied between and within species, reducing the rate of diffusion of particles via steric hindrance. In biofilms with low porosity, the EDCs for nutrient transport perpendicular to the substratum were significantly lower than the EDCs for nutrient transport parallel to the substratum. Here, we propose a reaction-diffusion model to describe the nutrient concentration within a bacterial biofilm that accounts for the depth dependence of the EDC.

Inflexibility of the plasma miRNA response following a high-carbohydrate meal in overweight insulin-resistant women.

CONTEXT: Metabolic inflexibility is a characteristic of insulin resistance, limiting the ability to transiently regulate oxidative metabolism and gene expression in response to nutrient availability. Little is known of the flexibility of post-transcriptional regulation, including circulatory miRNAs (c-miRNAs). DESIGN: The abundances of targeted c-miRNAs, with reported functions in metabolic regulation, were analysed in response to a high-carbohydrate meal in healthy weight insulin-sensitive (IS) and overweight insulin-resistant (IR) women. PARTICIPANTS: Age-matched healthy weight IS (n = 20, BMI = 24.3 ± 0.70) and overweight IR (n = 20, BMI = 28.6 ± 0.67) women. METHODS: An abundance of c-miRNAs was quantified prior to and following a high-carbohydrate breakfast meal (2500 kJ; 50% carbohydrate, 20% fat and 27% protein). Target genes of the differentially regulated c-miRNA were measured in RNA extracted from circulatory peripheral blood mononuclear cells (PBMCs). RESULTS: In healthy weight IS women, both miR-15a-5p (p = 0.03) and miR-17-5p (p < 0.01) levels were halved at 4 h post-meal. These miRNA remained unaltered following the same meal in the overweight IR women. Furthermore, amongst genes targeted by these miRNA, CPT1A (p = 0.01) and IL8 (p = 0.03) had also reduced expression 4 h post-meal only in the healthy weight IS women. CONCLUSIONS: The study findings provide preliminary evidence for a possible extension of metabolic inflexibility to include c-miRNAs. TRIAL REGISTRATION: The clinical trial is registered with Australian New Zealand Clinical Trials Registry under Trial registration: ANZCTR: ACTRN12615001108505. Registered on 21 October 2015.

Circulatory miRNA biomarkers of metabolic syndrome.

AIMS: Circulatory microRNAs (c-miRNAs) exert important roles in the molecular dysregulation of cardio-metabolic diseases. However, little is known whether dysregulated miRNA expression occurs when risk factors are elevated, as in the metabolic syndrome (MetS). This study quantified c-miRNA expression in individuals with MetS compared to healthy, further examining the relationship of gene pathways with the underlying pathogenesis. METHODS: Expression of 26 miRNAs was quantified in plasma from 40 women (20 healthy and 20 MetS) and 39 men (20 healthy and 19 MetS) by qPCR. In silico analysis was performed to investigate biological effects of the dysregulated miRNAs. Dysregulated miRNA expression was further validated in an independent cohort of 20 women (10 healthy and 10 MetS). RESULTS: Regression model adjusted for age and sex identified miR-15a-5p, miR-17-5p, miR-370-3p and miR-375 as important predictors of MetS presence. Analysis of predictive miRNAs in the validation cohort strengthened the relationship with miR-15a-5p and miR-17-5p expression. These miRNAs share genes involved in the regulation of metabolic pathways including insulin, wnt, fatty acid metabolism and AMPK. CONCLUSIONS: miR-15a-5p and miR-17-5p were identified as predictive biomarkers of MetS, irrespective of sexes, further demonstrating the relationship of c-miRNAs to known pathways of metabolic disturbances present in cardio-metabolic diseases.

A period of 10 weeks of increased protein consumption does not alter faecal microbiota or volatile metabolites in healthy older men: a randomised controlled trial.

Diet has a major influence on the composition and metabolic output of the gut microbiome. Higher-protein diets are often recommended for older consumers; however, the effect of high-protein diets on the gut microbiota and faecal volatile organic compounds (VOC) of elderly participants is unknown. The purpose of the study was to establish if the faecal microbiota composition and VOC in older men are different after a diet containing the recommended dietary intake (RDA) of protein compared with a diet containing twice the RDA (2RDA). Healthy males (74⋅2 (sd 3⋅6) years; n 28) were randomised to consume the RDA of protein (0⋅8 g protein/kg body weight per d) or 2RDA, for 10 weeks. Dietary protein was provided via whole foods rather than supplementation or fortification. The diets were matched for dietary fibre from fruit and vegetables. Faecal samples were collected pre- and post-intervention for microbiota profiling by 16S ribosomal RNA amplicon sequencing and VOC analysis by head space/solid-phase microextraction/GC-MS. After correcting for multiple comparisons, no significant differences in the abundance of faecal microbiota or VOC associated with protein fermentation were evident between the RDA and 2RDA diets. Therefore, in the present study, a twofold difference in dietary protein intake did not alter gut microbiota or VOC indicative of altered protein fermentation.

Multidrug resistance gene deficient (mdr1a-/-) mice have an altered caecal microbiota that precedes the onset of intestinal inflammation.

AIM: To compare caecal microbiota from mdr1a(-/-) and wild type (FVB) mice to identify differences in the bacterial community that could influence the intestinal inflammation. METHODS AND RESULTS: Caecal microbiota of mdr1a(-/-) and FVB mice were evaluated at 12 and 25 weeks of age using denaturing gradient gel electrophoresis (DGGE) and quantitative real-time PCR. DGGE fingerprints of FVB and mdr1a(-/-) mice (with no intestinal inflammation) at 12 weeks revealed differences in the presence of DNA fragments identified as Bacteroides fragilis, B. thetaiotaomicron, B. vulgatus and an uncultured alphaproteobacterium. Escherichia coli and Acinetobacter sp. were only identified in DGGE profiles of mdr1a(-/-) mice at 25 weeks (with severe intestinal inflammation), which also had a lower number of total bacteria in the caecum compared with FVB mice at same age. CONCLUSIONS: Differences found in the caecal microbiota of FVB and mdr1a(-/-) mice (12 weeks) suggest that the lack of Abcb1 transporters in intestinal cells due to the disruption of the mdr1a gene might lead to changes in the caecal microbiota. The altered microbiota along with the genetic defect could contribute to the development of intestinal inflammation in mdr1a(-/-) mice. SIGNIFICANCE AND IMPACT OF THE STUDY: Differences in caecal microbiota of mdr1a(-/-) and FVB mice (12 weeks) suggest genotype specific colonization. The results provide evidence that Abcb1 transporters may regulate host interactions with commensal bacteria. Future work is needed to identify the mechanisms involved in this possible cross-talk between the host intestinal cells and microbiota.

Initiation and elongation steps of mRNA translation are involved in the increase in milk protein yield caused by growth hormone administration during lactation.

The underlying molecular mechanisms that control milk yield and milk protein yield in domestic animals are not completely understood. In this study, the galactopoietic response to exogenous growth hormone (GH) was used as an experimental model to investigate the role of translation initiation and elongation in the regulation of milk protein synthesis in the mammary gland. A slow-release formula of commercially available GH was administered via a single subcutaneous injection to 4 lactating cows (GH group). A further 4 cows were given a single subcutaneous injection of saline (control group). Changes in mRNA transcript level and protein phosphorylation status of key members of the mammalian target of rapamycin (mTOR) pathway were assessed in mammary gland tissues of these animals using quantitative real-time PCR and Western blotting. The GH treatment enhanced the phosphorylation of ribosomal protein S6 and increased the protein abundance of eukaryotic initiation factor 4E (eIF4E) and eukaryotic elongation factor 2 (eEF2) proteins in the mammary gland of GH-treated animals. These results indicate a link between milk protein synthesis and the regulation of mRNA translation. The GH treatment did not change mRNA abundance of ribosomal protein S6, eIF4E, and eEF2, nor did it change the mRNA (mTOR, eEF2 kinase) or protein abundance of eEF2 kinase. These results demonstrate that GH administration changes mRNA translation initiation and elongation possibly via the mTOR pathway (suggested by the increased levels of ribosomal protein S6 phosphorylation), indicating that the mTOR pathway might be a potential control point in the regulation of milk protein synthesis in the mammary gland.

Regulation of Amino Acid Transporters and Sensors in Response to a High protein Diet: A Randomized Controlled Trial in Elderly Men.

BACKGROUND: The mammalian target of rapamycin complex 1 (mTORC1) is fundamental for many cellular processes, yet it is often dysregulated with aging. Increased amino acid (AA) availability is correlated with the expression of AA transporters (AAT) and mTORC1 activity. Although many AA sensors and mediators have been proposed to relay the AA signal to mTORC1, it has not yet been determined if chronic dietary intervention affects the expression of AAT, sensors and mediators and their relationships with mTORC1 activity. OBJECTIVE AND DESIGN: This study investigated whether the consumption of a diet containing either the current recommended daily allowance (RDA) of protein intake (0.8 g/kg/d) or twice the RDA (2RDA) for ten weeks affected the expression of targets associated with AA transport, sensing and mTORC1 regulation in 26 older men (70-81 years). METHOD: Muscle biopsies were collected before and after the intervention under fasting conditions. Diets were controlled by providing fully prepared meals and snacks. Western blot and quantitative polymerase chain reaction were used to measure protein and gene expression respectively. RESULTS: Consumption of 2RDA reduced the protein expression of L-type amino acid transporter 1 (LAT1). However, plasma leucine concentration and basal mTORC1 activity were unaltered. The downregulation of LAT1 did not affect the expression of AA sensors and mediators, including leucyl tRNA synthetase (LRS), cytosolic arginine sensor for mTORC1 (CASTOR1), Sestrin2 and Rag proteins. Instead, total ribosomal protein S6 (RPS6) was upregulated with 2RDA. CONCLUSION: Ten weeks of 2RDA diet did not affect the fasting mTORC1 signaling, but increased total RPS6 might suggest improved muscular translational capacity to maintain muscular mass.

Mammary transcriptome analysis of lactating dairy cows following administration of bovine growth hormone.

The galactopoietic effect of growth hormone (GH) in lactating ruminants is well established; however the mechanisms that mediate these effects are not well understood. The first objective of this study was to determine the effect of GH on the synthesis of the major casein and whey proteins. The second objective was to identify the genes and pathways that may be involved in mediating the effect of GH on milk synthesis. A single subcutaneous injection of a commercially available slow release formulation of GH (Lactatropin®), or physiological saline solution (control) was administered to non-pregnant dairy cows (n=4/group) in mid-late lactation. Milk samples were collected for composition analysis and mammary lobulo-alveolar tissue was collected postmortem 6 days post injection. Gene expression profiles were evaluated using either a 22 000 bovine complementary DNA microarray or quantitative PCR (qPCR), and microarrays were validated by qPCR. The yield of all the major casein and whey proteins was increased 32% to 41% in GH-treated cows, with the exception of α-lactalbumin yield which was elevated by 70% relative to controls. Treatment with GH treatment tended to increase the concentration of α-lactalbumin but had no effect on the concentration of any of the major milk proteins. Messenger RNA (mRNA) abundance of the major whey and casein genes, with the exception of α-s2-casein, was increased in response to GH compared with controls, which is consistent with the positive effect of GH on milk production. Treatment with GH treatment influenced the mRNA abundance of genes involved in cell growth and proliferation, transcriptional and translational regulation, actin cytoskeleton signalling, lipid metabolism and cell death. This study has provided new insights into the cell signalling that may be involved in mediating the effect of GH on milk production in the mammary gland of lactating dairy cows.

Tracking gastrointestinal transit of solids in aged rats as pharmacological models of chronic dysmotility.

BACKGROUND: Dysmotility in the gastrointestinal (GI) tract often leads to impaired transit of luminal contents leading to symptoms of diarrhea or constipation. The aim of this research was to develop a technique using high resolution X-ray imaging to study pharmacologically induced aged rat models of chronic GI dysmotility that mimic accelerated transit (diarrhea) or constipation. The 5-hydroxytryptamine type 4 (5-HT4 ) receptor agonist prucalopride was used to accelerate transit, and the opioid agonist loperamide was used to delay transit. METHODS: Male rats (18 months) were given 0, 1, 2, or 4 mg/kg/day prucalopride or loperamide (in dimethyl sulfoxide, DMSO) for 7 days by continuous 7-day dosing. To determine the GI region-specific effect, transit of six metallic beads was tracked over 12 h using high resolution X-ray imaging. An established rating scale was used to classify GI bead location in vivo and the distance beads had propagated from the caecum was confirmed postmortem. KEY RESULTS: Loperamide (1 mg/kg) slowed stomach emptying and GI transit at 9 and 12 h. Prucalopride (4 mg/kg) did not significantly alter GI transit scores, but at a dose of 4 mg/kg beads had moved significantly more distal than the caecum in 12 h compared to controls. CONCLUSIONS & INFERENCES: We report a novel high-resolution, non-invasive, X-ray imaging technique that provides new insights into GI transit rates in live rats. The results demonstrate that loperamide slowed overall transit in aged rats, while prucalopride increased stomach emptying and accelerates colonic transit.

The probiotic Escherichia coli Nissle 1917 inhibits propagating colonic contractions in the rat isolated large intestine.

The objective of this research was to test an in vitro motility model by investigating whether a probiotic that reduces diarrhea in humans would reduce motility in the rat colon in vitro. The probiotic Escherichia coli Nissle 1917 (EcN) the active ingredient in Mutaflor® was used as an example probiotic because it is effective for treating infectious diarrheal diseases. The effect of EcN on motility was compared in two colonic preparations. In distal colon segments EcN extract decreased the tension of spontaneous contractions by 74% and frequency by 46% compared with pre-treatment controls. In the whole large intestine the number of synchronized spontaneous propagating contractions decreased by 86% when EcN extract was applied externally and 69% when applied via the lumen compared with pre-treatment. From the inhibition produced by EcN extract in the distal colon segment a myogenic action was inferred and in the whole large intestine neural involvement was implicated. Both are consistent with its anti-diarrheal effect in humans.

Fourteen years of shigellosis in Dhaka: an epidemiological analysis.

We examined whether the proportion of Shigellae patients among diarrhoeal cases, the distribution, species, case-fatality rates and hospital visits changed over time in Dhaka. We isolated 19639 Shigella strains from 822812 diarrhoea cases treated at the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), between 1969 and 1982. The number of cases increased from 209 (2.5%) in 1969 to 4833 (7.7%) in 1976. Extrapolating from a 4% vigorous systematic sample of ICDDR,B hospital visits shigellosis cases and their proportion among diarrhoea cases increased to more than 9500 (12.0%) in 1981. The prevalence of various shigellae species altered over time. For example: in 1969 Shigella flexneri predominated in 74% of all Shigella cases; in 1973 Shigella dysenteriae accounted for 56%, and in 1981 Shigella flexneri again predominated (75%). More than 20% of all Shigella isolations were from infants: 60% in males and 40% in females. Over 7% of severe cases of Shigella infection referred from the outpatient department and admitted for treatment died. Nearly 40% of all the Shigella deaths were in infants of less than a year old while 49% were in 1-4 year old children. Increasing prevalence of shigellosis appears to be an important cause of diarrhoea in Dhaka especially among children. Areas with poor sanitation and water supply had higher prevalence. However, hospitalized cases represented a fraction of the actual problem. Resistance to antibiotics appears to be increasing and the development of new drugs and preventive methods within economic reach of less developed countries are crucial for reduction of the disease and related deaths.

Use of mid-upper arm circumference for evaluation of nutritional status of children and for identification of high-risk groups for malnutrition in rural Bangladesh.

Measurements of mid-upper arm circumference (MUAC) of 8,881 children were considered cross-sectionally to determine the effects of diarrhoea, breast-feeding, and birth-spacing on the nutritional status of children in rural Matlab, Bangladesh. It was observed that age was one of the most significant determinants of child nutrition. The younger children (< 2 years) had significantly higher levels of severe malnutrition than the children aged 2 years or older. Children who had diarrhoea during the last 12 months prior to the study had significantly (p < 0.001) higher severe malnutrition than the children who did not suffer from diarrhoea. Children born with a longer interval after birth of an elder sibling (24+ months) and who were breastfed for a longer duration (2-3 years) were less likely to be severely malnourished than those who were born with a shorter birth interval or who terminated breast-feeding prior to 2 years of age. Education of mothers, housing space, family size, religion, and sex of children had significant effects on the nutritional status of children. Results of the study suggest that MUAC is a potential anthropometric indicator of child nutrition.

Socioeconomic and health implications of adult deaths in families of rural Bangladesh.

Effects of adult deaths on subsequent health and socioeconomic well-being of rural families of Bangladesh were examined. Data for this study were drawn from the longitudinal Sample Registration System (SRS) operational in two rural areas of the then MCH-FP Extension Project (Rural) of ICDDR,B. In total, deaths of 327 married adults aged 15-59 years, during January 1983-December 1987, were reviewed. The families of the deceased were followed up for five years after death. Factors, such as survival status of children, educational status of children aged 6-12 years, and out-migration status among adolescents aged 12-20 years in those families, was observed and recorded. A control group of 3,350 families experiencing no adult deaths was also followed up for five years. The health and socioeconomic impacts on children in both the groups five years after death of the adult were compared. The findings of the study showed that negative impact was more pronounced among the children of poor families, and the female children were most severely affected. Death of a father or a mother was associated with a higher rate of out-migration (especially marriage) of adolescent daughters. An adult death was associated with a significantly higher mortality risk of children during the five years following death of the adult. These child-mortality risks were significantly higher when an adult female died, and when the index child was a female and/or aged less than five years at the time of death of an adult. The children, aged 6-12 years, in families where a parent had died were significantly more likely to be uneducated and out-of-school after the death of a father or a mother compared to the children in families where neither of the parents had died. This finding remained valid even after controlling for the educational status of the parents who died and of those who did not die. Since the study used a limited number of independent variables and since there is a need to understand the specific reasons why such significant differences occurred, it is recommended to conduct a more in-depth qualitative study to know more clearly the nature and mechanisms of the socioeconomic and health impacts of death of an adult on the family and the society.

An in vitro rat model of colonic motility to determine the effect of ß-casomorphin-5 on propagating contractions.

Beta-casomorphin-5 (ßCM-5) is a milk-derived bioactive peptide that slows gastro-intestinal transit (GIT) in vivo and blocks the peristaltic reflex in the guinea pig colon in vitro. We wanted to establish an in vitro model system in which effects of dairy-derived substances containing opioid peptides on intestinal motility can be assessed and used to predict in vivo outcomes. Because ßCM-5 is an opioid agonist that acts on enteric neurons, we used this substance to compare two different isolated colonic tissue preparations to determine which would more closely mimic the in vivo response previously reported in the literature. We compared and characterized the effects of ßCM-5 on spontaneous contractions in isolated segments of distal colon (1 cm length) compared with propagating contractions along the isolated intact large intestine (22 cm length). In short segments of distal colon, ßCM-5 increased the tension and frequency of spontaneous contractions in a concentration-dependent manner. At 20 µM ßCM-5 tension increased by 71 ± 17% and the frequency doubled (n = 9), effects inhibited by naloxone (n = 7) and therefore mediated by opioid receptors. In contrast 20 µM ßCM-5 disrupted propagating contractions in the large intestine preparation. At 20 µM ßCM-5 reduced the proportion of contractions initiated in the proximal colon reaching the rectum by 83 ± 11% (n = 5) and this effect was also inhibited by naloxone, consistent with altered GIT reported in vivo. Our results demonstrate that the isolated whole large intestine provides an ideal preparation that mimics the reduced propagation of GIT in vivo in response to an opioid agonist, whereas short colon segments did not. The findings of the current study reveal that preserving large segments of intact large intestine, and hence intact enteric neural circuitry provides an ideal in vitro model to investigate the effect of opioid receptor modulators on intestinal transit.