Associations Between Variations in Breast Anatomy and Early Breastfeeding Challenges

Background: Mothers with anatomic variability (e.g., shorter, wider nipples; denser areolas) may experience breastfeeding challenges disproportionately. Research aim: To examine whether variations in breast anatomy are associated with risk for early breastfeeding challenges. Methods: Participants included mothers \u3c 6 weeks postpartum. Nipple base width, nipple length, and areolar density were measured on the right and left breast separately. Experiences with early breastfeeding challenges were determined through a combination of maternal report and clinical assessment. Results: Participants (N = 119) had an average nipple diameter of 23.4 (SD = 3.0) mm for left nipples and 23.5 (SD = 3.0) mm for right nipples (range = 10–34 mm). Average nipple length was 8.5 (SD = 3.2) mm for left breasts and 9.1 (SD = 3.2) mm for right breasts (range = 5–20 mm); 35% of participants had dense areolas on the left breast and 36% had dense areolas on the right breast. The combination of wider and longer nipples was associated with greater risk for difficulties with latch; the combination of wider nipples and denser areolas was associated with greater risk for sore nipples. For participants with more dense areolas, shorter and wider nipples were associated with greater risk for low milk supply and slow infant weight gain. For participants with less dense areolas, longer and wider nipples were associated with greater risk for low milk supply and slow infant weight gain. Conclusion: Further research is needed to understand how measures of breast anatomy can be used to guide targeted intervention efforts

Effectiveness of Three Decontamination Treatments against Influenza Virus Applied to Filtering Facepiece Respirators

Filtering facepiece respirators (FFRs) are recommended for use as precautions against airborne pathogenic microorganisms; however, during pandemics demand for FFRs may far exceed availability. Reuse of FFRs following decontamination has been proposed but few reported studies have addressed the feasibility. Concerns regarding biocidal efficacy, respirator performance post decontamination, decontamination cost, and user safety have impeded adoption of reuse measures. This study examined the effectiveness of three energetic decontamination methods [ultraviolet germicidal irradiation (UVGI), microwave-generated steam, and moist heat] on two National Institute for Occupational Safety and Health-certified N95 FFRs (3M models 1860s and 1870) contaminated with H5N1. An aerosol settling chamber was used to apply virus-laden droplets to FFRs in a method designed to simulate respiratory deposition of droplets onto surfaces. When FFRs were examined post decontamination by viral culture, all three decontamination methods were effective, reducing virus load by \u3e4 log median tissue culture infective dose. Analysis of treated FFRs using a quantitative molecular amplification assay (quantitative real-time polymerase chain reaction) indicated that UVGI decontamination resulted in lower levels of detectable viral RNA than the other two methods. Filter performance was evaluated before and after decontamination using a 1% NaCl aerosol. As all FFRs displayed \u3c5%penetration by 300-nm particles, no profound reduction in filtration performance was caused in the FFRs tested by exposure to virus and subsequent decontamination by the methods used. These findings indicate that, when properly implemented, these methods effectively decontaminate H5N1 on the two FFR models tested and do not drastically affect their filtering function; however, other considerations may influence decisions to reuse FFRs

Prevalence of Hepatitis C Virus and its genotypes among a cohort of drug users in Kenya

Background: Prevalence of hepatitis C virus and that of its main genotypes varies between the worlds geographic regions. The risk factors for infection with HCV include blood transfusion, tattoing and injecting drug use. Objectives: To examine the prevalence of HCV and determine its main genotypes among a cohort of drug users in Kenya. Design: A laboratory based study. Setting: Hepatitis research laboratory in the Centre for Virus Research at the Kenya Medical Research Institute, Nairobi. Subjects: Three hundred and fourteen male and 19 female intravenous and non-intravenous drug users aged between 15-55 years. Results: Seventy four (22.2%) out of 333 samples tested positive for anti-HCV. Sixty nine out of the 74 serum samples were assayed for HCV RNA and 38 (55.5%) were positive. The RNA positive samples were further subjected to sequencing and 19 (73%) of the samples were classified as genotype la, while seven (27%) samples were classified as genotype 4. Genotypes 2, 3, 5 and 6 were not identified in this study. Conclusions: These results demonstrate a high HCV infection prevalence among this cohort of drug users (22.2 %) as compared to that of the general population, which is estimated to be 0.2- 0.9%. The study also confirms the presence of at least two major genotypes among Kenyan drug users (genotypes 1 and 4). East African Medical Journal Vol. 85 (7) 2008: pp. 318-32

Food safety metrics relevant to low- and middle-income countries

London School of Hygiene and Tropical MedicineRoyal Veterinary College, LondonWorld Health OrganizationFood and Agriculture Organization of the United Nation

Genome-wide association mapping for identification of sheath blight resistance loci from wild rice Oryza rufipogon

Sheath blight (ShB) caused by Rhizoctonia solani is one of the serious constraints that hamper global rice production. It causes severe yield loss of up to 69% under favorable environmental conditions. The application of chemical fungicides remains the primary approach for the management of this disease. But, overuse of chemical fungicides causes potential health and environmental risk. The use of host plant resistance is a very effective, economic, and sustainable strategy to control sheath blight disease in rice. In this report, we have evaluated 405 accessions of Oryza rufipogon for four ShB-related traits i.e. lesion height (LH), plant height (PH), relative lesion length (RLH), and disease score (DS) during the years 2015, 2016, and 2017. A total of 44,109 high-quality SNP markers on 301 accessions were employed to identify significant marker-trait associations using a genome-wide association study (GWAS). The GWAS analysis revealed a total of 22 significant SNPs associated with the ShB-related traits distributed on all the rice chromosomes except 10 and 12. Among them, eleven were associated with RLH, seven with PH, and one each with LH and DS. The SNPs on chromosomes 3 and 9 were associated with multiple traits. Furthermore, seven ShB resistance loci were also found to be co-localized with previously reported ShB resistance genes/QTLs. These findings provide valuable information to identify key SNPs associated with ShB resistance. Significantly associated SNPs could be used for introgression of ShB resistance traits into rice cultivars using marker-assisted selection

Cultural studies on Ustilaginoidea virens, the incitant of false smut of rice (Oryza sativa)

A study was carried out to find out the favourable culture media for mass multiplication and the effect of carbon sources and duration on chlamydospore germination of Ustilaginoidea virens (Cook.) Tak. Different synthetic and semi synthetic solid, liquid media, substrate media were evaluated for mass multiplication of U. virens. Potato sucrose broth was the best medium for fast mycelia growth (104.80 mg) and sporulation (6.78 × 105 spores/ml), potato dextrose broth also favored mycelial growth, whereas corn meal dextrose broth was not suitable. Out of four solid media tested, maximum colony diameter (68.74 mm) and sporulation (6.86 × 105 spores/ml) was produced by potato sucrose agar followed by potato dextrose agar. Maximum sporulation was produced on substrate media based on barley seeds (5.54 × 105 spores/ml) followed by rice seeds (3.72 × 105 spores/ml) whereas rice husk based media produced minimum sporulation. Higher concentration of sucrose and dextrose at 2 per cent supported maximum germination of spores of U. virens and sucrose was found superior in inducing germination than dextrose. The results of this study help to understand the physiological and biochemical requirements for the growth and development of the pathogen, which could serve as an input in disease management to minimize the effect of false smut disease on rice

Seizures, ataxia and parvalbumin-expressing interneurons respond to selenium supply in Selenop-deficient mice

Mice with constitutive disruption of the Selenop gene have been key to delineate the importance of selenoproteins in neurobiology. However, the phenotype of this mouse model is exquisitely dependent on selenium supply and timing of selenium supplementation. Combining biochemical, histological, and behavioral methods, we tested the hypothesis that parvalbumin-expressing interneurons in the primary somatosensory cortex and hippocampus depend on dietary selenium availability in Selenop−/− mice. Selenop-deficient mice kept on adequate selenium diet (0.15 mg/kg, i.e. the recommended dietary allowance, RDA) developed ataxia, tremor, and hyperexcitability between the age of 4–5 weeks. Video-electroencephalography demonstrated epileptic seizures in Selenop−/− mice fed the RDA diet, while Selenop ± heterozygous mice behaved normally. Both neurological phenotypes, hyperexcitability/seizures and ataxia/dystonia were successfully prevented by selenium supplementation from birth or transgenic expression of human SELENOP under a hepatocyte-specific promoter. Selenium supplementation with 10 μM selenite in the drinking water on top of the RDA diet increased the activity of glutathione peroxidase in the brains of Selenop−/− mice to control levels. The effects of selenium supplementation on the neurological phenotypes were dose- and time-dependent. Selenium supplementation after weaning was apparently too late to prevent ataxia/dystonia, while selenium withdrawal from rescued Selenop−/− mice eventually resulted in ataxia. We conclude that SELENOP expression is essential for preserving interneuron survival under limiting Se supply, while SELENOP appears dispensable under sufficiently high Se status