Characterization of chemokine receptors expressed in primitive blood cells during human hematopoietic ontogeny

Chemokines are capable of regulating a variety of fundamental processes of hematopoietic cells that include proliferation, differentiation, and migration. To evaluate potential chemokine signaling pathways important to the regulation of primitive human hematopoietic cells, we examined chemokine receptor expression of highly purified subpopulations of uncommitted human blood cells. CXCR1-, CXCR2-, CXCR4-, and CCR5-expressing cells were detected by flow cytometry among human blood subsets depleted of lineage-restricted cells (Lin(-)) derived from adult bone marrow, mobilized peripheral blood, cord blood (CB), and circulating fetal blood. Although these chemokine receptors could be detected on Lin(-) cells throughout human development, only CXCR4 could be detected in CD34(-)CD38(-)Lin(-) and CD34(+)CD38(-)Lin(-) subfractions enriched for stem cell function, suggesting that independent of ontogeny, CXCR4-mediated signals are critical to primitive hematopoiesis. Distinct to other stages of human hematopoietic development, primitive CB cells expressed higher levels of CXCR1, CXCR2, CCR5, and CXCR4 on both CD34(-)CD38(-)Lin(-) and CD34(+)CD38(-)Lin(-) subsets. Isolation of these fractions revealed expression of additional chemokine receptors CCR7, CCR8, and Bonzo (STRL133), whereas BOB (GPR15) could not be detected. Our study illustrates that rare uncommitted hematopoietic cells express chemokine receptors not previously associated with primitive human blood cells. Based on these results, we suggest that signaling pathways mediated by chemokine receptors identified here may play a fundamental role in hematopoietic stem cell regulation and provide alternative receptor targets for retroviral pseudotyping for genetic modification of repopulating cells.     

Determination of an Acceptable Portion Size of Daal for a Bangladeshi Community-Based Iron Intervention in Adolescent Girls: A Feasibility Study

Widely consumed daal (lentils) in Bangladesh are an ideal vehicle for iron (Fe) fortification; however, an acceptable portion size in meals needs to be determined to carry out a community feeding study in at-risk adolescent girls. A non-randomized crossover trial was conducted with n = 100 Bangladeshi girls (12.9 ± 2.0 years of age). Two recipes (thin and thick) and three portion sizes (25 g, 37.5 g, 50 g of raw lentil) of daal were served with 250 g of cooked white rice in a counter-balanced manner over 12 weeks. Each meal was fed to participants 5 days/week for two weeks. Ratings of hunger, satiety, and palatability were measured before and after each meal using Visual Analog Scales (VAS). The thick preparation in the 37.5 g portion (~200 g cooked) elicited higher VAS ratings of hunger, satiety, and palatability compared to all other meals. The 50 g portion of the thin preparation had VAS ratings similar to those of the 37.5 g thick preparation. Consuming the 37.5 g portion of fortified daal would provide 6.9 mg Fe/day to girls in a community-based effectiveness study. This would meet ~86% and ~46% of the Recommended Dietary Allowance (RDA) for Fe for girls aged 9–13 and 14–18 years, respectively.     

Molecular evolution of the hemagglutinin and neuraminidase genes of pandemic (H1N1) 2009 influenza viruses in Sendai, Japan, during 2009–2011

Analyzing the evolutionary pattern of the influenza A(H1N1)pdm09 strain in different regions is important for understanding its diversification. We therefore conducted this study to elucidate the genetic variability and molecular evolution of the influenza A(H1N1)pdm09 strains that circulated during the 2009–2010 and 2010–2011 influenza seasons in Sendai, Japan. Nasopharyngeal swab specimens were collected from patients with influenza-like illnesses who visited outpatient clinics in Sendai City, Japan, from September 2009 to April 2011. A total of 75 isolates were selected from September 2009 to April 2011 to analyze the genetic changes in the entire hemagglutinin 1 (HA1) segment of the HA gene and the neuraminidase (NA) gene based on sequence analysis. Bayesian coalescent Markov chain Monte Carlo analyses of HA1 and NA gene sequences were performed for further analysis. High sequence identities were observed for HA1 and NA in influenza A(H1N1)pdm09, displaying 99.06 and 99.33 % nucleotide identities, respectively, with the A(H1N1)pdm09 vaccine strain A/California/07/2009. The substitution rates of nucleotides for HA1 in the 2009–2010 and 2010–2011 were 1.5 × 10^?3 and 1.6 × 10^?3 substitutions per site per year, respectively. Phylogenetic tree analysis demonstrated that Sendai isolates were clustered into global clade 7, which is characterized by an S203T mutation in the HA1 gene. Moreover, two distinct circulation clusters were present in the 2010–2011 season. Mutations were present in antigenic or receptor-binding domains of the HA1 segment, including A141V, S143G, S183P, S185T, and S203T. The Bayesian skyline plot model illustrated a steady rate for the maintenance of genetic diversity, followed by a slight increase in the later part of the 2010–2011 season. Selection analysis revealed that the HA1 (position 197) and NA (position 46) sites were under positive selection; however, no known mutation conferring resistance to NA inhibitors such as H275Y was observed. The effect on control of the influenza A(H1N1)pdm09 virus, including vaccine strain selection, requires continuous monitoring of the strain by genetic surveillance.     

Cytotoxic and photocatalytic studies of hexagonal boron nitride nanotubes: a potential candidate for wastewater and air treatment

Boron nitride (BN) nanomaterials are rapidly being investigated for potential applications in biomedical sciences due to their exceptional physico-chemical characteristics. However, their safe use demands a thorough understanding of their possible environmental and toxicological effects. The cytotoxicity of boron nitride nanotubes (BNNTs) was explored to see if they could be used in living cell imaging. It was observed that the cytotoxicity of BNNTs is higher in cancer cells (65 and 80%) than in normal cell lines (40 and 60%) for 24 h and 48 h respectively. The influence of multiple experimental parameters such as pH, time, amount of catalyst, and initial dye concentration on percentage degradation efficiency was also examined for both catalyst and dye. The degradation effectiveness decreases (92 to 25%) as the original concentration of dye increases (5–50 ppm) due to a decrease in the availability of adsorption sites. Similarly, the degradation efficiency improves up to 90% as the concentration of catalyst increases (0.01–0.05 g) due to an increase in the adsorption sites. The influence of pH was also investigated, the highest degradation efficiency for MO dye was observed at pH 4. Our results show that lower concentrations of BNNTs can be employed in biomedical applications. Dye degradation properties of BNNTs suggest that it can be a potential candidate as a wastewater and air treatment material.

Photocatalytic degradation studies of methyl orange using BNNTs.     

Effects of early life adversity on immune function and cognitive performance: results from the ALSPAC cohort

Social Psychiatry and Psychiatric Epidemiology - Early life adversity (ELA) is a significant risk factor for mental health disorders. One hypothesised mechanism by which this occurs is via an...     

Ingestion of an indigestible saccharide, difructose anhydride III, partially prevents the tannic acid-induced suppression of iron absorption in rats

Dietary tannic acid (TA) inhibits iron absorption and some indigestible oligosaccharides have been shown to promote mineral absorption. In this study, we examined whether difructose anhydride III (DFA III) or fructooligosaccharide (FOS) stimulate iron absorption in TA-fed rats. Two experiments were conducted using male Sprague-Dawley rats (weighing 90-110 g) in a randomized block design. Rats were fed control, DFA III or FOS (30 g/kg) diets in expt. 1, and control, TAcontrol, TAFOS or TADFA III (TA, 15 g/kg) diets in expt. 2 for 3 wk during which blood sampling was performed weekly and fecal collection twice. In expt. 1, apparent iron absorption was higher (P < 0.001) in the DFA III-fed (65.7 and 55.9%, d 8-10 and 19-21) and FOS-fed (59.9%, d 19-21) groups than in the control group (48.4 and 45.4%, d 8-10 and 19-21) without differences in blood hemoglobin concentrations or hematocrits. TA feeding reduced hemoglobin concentrations and hematocrits (119.1 g/L, 0.360; P < 0.001), and the feeding of TADFA III partially improved this anemic condition (129.6 g/L, 0.403), whereas TAFOS feeding did not influence these variables (120.6 g/L, 0.342; expt. 2). Iron absorption was lower in the TA-fed groups (19.8%; P < 0.001) than in the control group (49.4%), whereas the absorption in both TA-fed indigestible sugar groups was higher (DFA III, 43.2 and 38.2%, d 8-10 and 19-21; FOS, 39.4%, d 8-10; P < 0.001) than in the TA-control group except for the TAFOS-fed group (25.1%, d 19-21). Serum iron concentrations, unsaturated iron-binding capacities, total iron-binding capacities and transferrin saturations (%) were not improved by the feeding of TADFA III or TAFOS. Furthermore, liver iron concentrations were decreased by TA feeding (P < 0.001) and were not increased by the feeding of indigestible sugars. The feeding of DFA III or FOS decreased the pH of the cecal contents (P < 0.001) while increasing major organic acid pools. In all groups fed TA, approximately 18% of the ingested TA was recovered in the feces. Our results demonstrate that TA reduces iron absorption and induces anemia, conditions that are partially prevented by the feeding of DFA III, but not FOS.     

Factors affecting newborn care practices in Bangladesh

Newborn care is of immense importance for the proper development and healthy life of a baby. Although child and infant mortality in South Asia has reduced substantially, the rate of neonatal mortality is still high, although these deaths can be prevented by adopting simple interventions at the community level. The aim of the study was to identify the associated factors which affect newborn care practices. Data for the study were drawn from the Bangladesh Demographic and Health Survey 2007, in which 6150 mothers were considered. The mean age of the mothers was 18 (±3.2) years. A little over 62% of the pregnant women received at least one antenatal check-up during the entire period of their pregnancy. About 70% of deliveries were conducted at home either by unskilled family members or by relatives. A clean instrument was used for cutting the cord of 87% of the newborn babies, while about 34% of them were reported to have had their first bath immediately after delivery. Initiation of breast feeding immediately after birth was practised in only about 19% of the cases. Compared with mothers with no education, those with secondary or higher levels were associated with clean cord care [odds ratio (OR) = 1.3, 95% confidence interval (CI) 1.0, 1.9] and early breast feeding [OR = 1.6, 95% CI 1.2, 2.2]. The study revealed an urgent need to educate mothers, and train traditional birth attendants and health workers on clean delivery practices and early neonatal care. Increasing the number of skilled birth attendants can be an effective strategy to increase safe delivery practices, and to reduce delivery complications.