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In Bangladesh, 36% of children under the age of 5 are moderately or severely stunted, impeding the country’s overall public health outcomes. Some differences have been found in the associations of risk factors and two forms of stunting; therefore, investigating why these differences exist is necessary. This study aimed to determine the prevalence and risk factors for moderate and severe stunting in Bangladeshi children < 5 years old. Bangladesh Demographic and Health Survey 2014 (BDHS 2014) data were analyzed in this study; the information of 7131 mother-child pairs was available. Height-for-age z-scores (HFAz) according to the World Health Organization (WHO) 2006 growth standards were used to define moderate (HFAz

The antimicrobial properties of honey have stimulated interest in evaluating it as an alternative to antibiotics for cryopreserved buffalo semen. Acacia nilotica, Brassica campestris and Ziziphus j...

Key physiological differences between bacterial and mammalian metabolism provide opportunities for the development of novel antimicrobials. We examined the role of the multifunctional enzyme S-adenosylhomocysteine/Methylthioadenosine (SAH/MTA) nucleosidase (Pfs) in the virulence of S. enterica var Typhimurium (S. Typhimurium) in mice, using a defined Pfs deletion mutant (i.e. Δpfs). Pfs was essential for growth of S. Typhimurium in M9 minimal medium, in tissue cultured cells, and in mice. Studies to resolve which of the three known functions of Pfs were key to murine virulence suggested that downstream production of autoinducer-2, spermidine and methylthioribose were non-essential for Salmonella virulence in a highly sensitive murine model. Mass spectrometry revealed the accumulation of SAH in S. Typhimurium Δpfs and complementation of the Pfs mutant with the specific SAH hydrolase from Legionella pneumophila reduced SAH levels, fully restored growth ex vivo and the virulence of S. Typhimurium Δpfs for mice. The data suggest that Pfs may be a legitimate target for antimicrobial development, and that the key role of Pfs in bacterial virulence may be in reducing the toxic accumulation of SAH which, in turn, suppresses an undefined methyltransferase.

Streptococcus suis is a causative agent of meningitis, polyarthritis, and polyserositis in swine, and it is a major cause of zoonotic meningitis in humans. Here, we investigate epigenetic gene regulation in S. suis by multiple phasevarions controlled by the phase-variable type III DNA methyltransferase ModS., Streptococcus suis is a significant cause of bacterial meningitis in humans, particularly in Southeast Asia, and is a leading cause of respiratory and invasive disease in pigs. Phase-variable DNA methyltransferases, associated with restriction-modification (R-M) systems, are a source of epigenetic gene regulation, controlling the expression of multiple genes. These systems are known as phasevarions (phase-variable regulons) and have been characterized in many host-adapted bacterial pathogens. We recently described the presence of a Type III DNA methyltransferase in S. suis, ModS, which contains a simple sequence repeat (SSR) tract within the open reading frame of the modS gene and which differed in length between individual strains. We also observed that multiple allelic variants of the modS gene were present in a population of S. suis isolates. Here, we demonstrate that a biphasic ON-OFF switching of expression occurs in the two most common ModS alleles, ModS1 and ModS2, and that switching is dependent on SSR tract length. Furthermore, we show using single-molecule real-time (SMRT) sequencing that ModS1 and ModS2 are active methyltransferases in S. suis. ON-OFF switching of each ModS allele results in the regulation of distinct phasevarions, with the ModS2 phasevarion impacting growth patterns and antibiotic resistance. This is the first demonstration of a phase-variable Type III DNA methyltransferase in a Gram-positive organism that controls a phasevarion. Characterizing the phenotypic effects of phasevarions in S. suis is key to understanding pathogenesis and the development of future vaccines. IMPORTANCE Streptococcus suis is a causative agent of meningitis, polyarthritis, and polyserositis in swine, and it is a major cause of zoonotic meningitis in humans. Here, we investigate epigenetic gene regulation in S. suis by multiple phasevarions controlled by the phase-variable Type III DNA methyltransferase ModS. This is the first characterized example of a Type III R-M system regulating a phasevarion in a Gram-positive organism. We demonstrate that biphasic ON-OFF switching of ModS expression results in differences in bacterial growth and antibiotic resistance. Understanding the effects of ModS phase variation is required to determine the stably expressed antigenic repertoire of S. suis, which will direct and inform the development of antimicrobial treatments and vaccines against this important pathogen.

Sperm sexing through flow-sorting technology is relatively expensive, requires considerable technical support and is actually not practicable in many developing countries. The aim of this study was to investigate the feasibility of producing enriched pools of X or Y chromosome-bearing sperm by a modified swim-up method. For this purpose semen was collected from five mature Nili-Ravi buffalo bulls for a period of six weeks. The qualifying ejaculates were divided into two aliquots for further processing through modified swim-up or control (untreated). After processing, semen was cryopreserved in tris citric acid extender using standard techniques. Semen quality was assessed at pre dilution, post dilution and post thawing. Validation of technique was done by using SYBR® green real time PCR using two sets of primers, PLP and SRY for X and Y chromosome of buffalo genes, respectively. Sperm recovery rates, pre freeze and post thaw sperm quality were found significantly higher in X chromosome bearing sperm fraction than Y chromosome bearing fraction and control. Mean fold relative expression of X bearing sperm was significantly higher (4-5 fold) in X chromosome bearing fraction of supernatant than Y chromosome bearing fraction (0.06 fold), similarly mean fold relative expression of Y chromosome bearing sperm was significantly higher in Y chromosome bearing fraction (4 fold) of supernatant than X chromosome bearing fraction (0.15 fold) compared to control (1.00). In conclusion, a modified swim up method proved to be an effective method for Nili-Ravi buffalo sperm sexing as validated by real time PCR.

The present study was conducted to investigate the effect of omega-3 poly unsaturated fatty acid (PUFA), α-linolenic acid (ALA; 18:3 n-3) on the in vitro maturation (IVM) of buffalo oocytes and subsequent embryonic development. Buffalo cumulusoocyte complexes (COCs; n = 2282) were in vitro matured in TCM-199 (0.6% fatty acid free bovine serum albumin, 0.02 Units/ml FSH, 1 µg/ml 17-β-estradiol, 10 µg/ml epidermal growth factor, 50 µg/ml gentamicin) supplemented with 0 (control), 25, 50, 100, 150 or 300 µm ALA under an atmosphere of 5% CO2 in air at 38.5oC for 22-24 h. The matured oocytes were then fertilized in Tyrode’s Albumin Lactate Pyruvate (TALP) medium and cultured in synthetic oviductal fluid (SOF) medium. Concentrations up to 100 μm ALA improves (P ≤ 0.05) the cumulus expansion compared to control. Higher percentage of oocytes reaching MII stage was observed at 50 μm and 100 μm of ALA compared to control (P ≤ 0.05). Concentrations of 150 and 300 µm ALA were detrimental both for cumulus expansion and nuclear maturation rate of buffalo oocytes. Moreover, supplementation with 100 μm ALA improved (P ≤ 0.05) cleavage rate compared to control and treatment with 50 and 100 μm ALA yielded significantly higher morulae compared to control. The results of present study indicate that the supplementation with 100 μm ALA to the IVM medium improves nuclear maturation rate of buffalo oocytes and subsequent early embryonic development.

Salmonella isolates should be distinguished as it may assist in tracing the source of an outbreak and monitoring trends in antimicrobial resistance associated with a particular type. The specific detection of these Salmonella serotypes is therefore extremely important in order to attribute an isolate to a previously known epidemic outbreak. The present investigation was to isolate and identify S. Gallinarum, to study variation in the profile of outer membrane proteins (OMPs) and to determine in vitro antibiogram of S. Gallinarum in poultry. A total of 228 faecal samples and 22 visceral samples suspected for Salmonellosis were collected, of these 15 samples (6.0%) were found positive for S. Gallinarum. In the present study, rfbS gene sequence was helpful in the serotype-specific detection of S. Gallinarum giving a 187 bp product. Salmonella Gallinarum crude protein extracts determined by SDSPAGE showed migration of OMPs as several bands at approximate moleculer weights of appx. 45 kDa, 55 kDa, 64 kDa, 65 kDa, 74 kDa, 110 kDa, 120 kDa, 135 kDa, 150 kDa,155 kDa, 200 kDa and above 200 kDa. The study indicated a definite variation in the profile of OMPs of various Salmonella Gallinarum strains with major OMPs in the range of appx 80-100 kDa which could be the target for vaccine production. All the isolates tested against 14 antimicrobial agents showed variable susceptibility pattern with highest resistance to nalidixic acid, ampicillin and sulphadiazine and sensitivity to chloramphenicol, gentamicin and enrofloxacin.

Phase-variable DNA methyltransferases control the expression of multiple genes via epigenetic mechanisms in a wide variety of bacterial species. These systems are called phasevarions, for phase-variable regulons. Phasevarions regulate genes involved in pathogenesis, host adaptation and antibiotic resistance. Many human-adapted bacterial pathogens contain phasevarions. These include leading causes of morbidity and mortality worldwide, such as non-typeable Haemophilus influenzae , Streptococcus pneumoniae and Neisseria spp. Phase-variable methyltransferases and phasevarions have also been discovered in environmental organisms and veterinary pathogens. The existence of many different examples suggests that phasevarions have evolved multiple times as a contingency strategy in the bacterial domain, controlling phenotypes that are important in adapting to environmental change. Many of the organisms that contain phasevarions have existing or emerging drug resistance. Vaccines may therefore represent the best and most cost-effective tool to prevent disease caused by these organisms. However, many phasevarions also control the expression of current and putative vaccine candidates; variable expression of antigens could lead to immune evasion, meaning that vaccines designed using these targets become ineffective. It is therefore essential to characterize phasevarions in order to determine an organism’s stably expressed antigenic repertoire, and rationally design broadly effective vaccines.

WOS: 000477988500001, PubMed: 31417913, Bull fertility, ability of the sperm to fertilize and activate the egg and support embryo development, is vital for cattle reproduction and production. Even though majority of histories are replaced by protamines, some histories are retained in sperm. It is known that chromatin remodeling during spermatogenesis results in dynamic changes in sperm chromatin structure through post-translational modifications (PTM) of sperm histones, which are important for regulation of gene expression. However, amounts of sperm Histone 4 (H4), its acetylated form (H4 acetyl), and to what extent these molecular attributes influence sperm chromatin structure and bull fertility are unknown. These gaps in the knowledge base are important because they are preventing advances in the fundamental science of bovine male gamete and improvement of bull fertility. The objective of this study was to test the hypothesis that expression dynamics as well as PTM of sperm H4 are associated with bull fertility. Flow cytometry was utilized to quantify H4 and H4 acetylated form in sperm from seven high and seven low fertility Holstein bulls. The results indicated that the average number of cells with H4 or H4 acetyl expression in high and low fertility bull sperm were 34.6 +/- 20.4, 1.88 +/- 1.8, 15.2 +/- 20.8, and 1.4 +/- 1.2, respectively. However, the sperm enriched in both H4 and H4 acetyl were different between high and low fertility groups (3.5 +/- 0.6; 1.8 +/- 0.8; P = 0.043). The localization and detection of H4 and H4 acetylation were measured by immunocytochemistry which revealed that H4 and H4 acetylation were equally distributed in the sperm head of high and low fertility sires. Western blotting results confirmed the presence of the H4 and its acetylated form in the sperm. Bioinformatics studies demonstrated that H4 is highly conserved among mammalians, and have significant gene ontology on spermatogenesis, early embryo implantation, and sperm capacitation. The results are significant because it demonstrates the replacement of canonical histone H4 into modified H4 acetylation in sperm and regulate its dynamics which is crucial for bull fertility and reproductive biotechnology. These findings advance fundamental science of mammalian early development and reproductive biotechnology., Mississippi Agricultural Forestry Experiment Station; Alta Genetics Inc., Wisconsin, USA; Coordination for the improvement of higher education personnel (CAPES) from BrazilCAPES; Netaji-Subhas Indian Council of Agricultural Research (ICAR)Indian Council of Agricultural Research (ICAR); Turkish Ministry of National EducationMinistry of National Education - Turkey, Study funded in part by Mississippi Agricultural Forestry Experiment Station, and by Alta Genetics Inc., Wisconsin, USA. EBM was funded through a competitive fellowship from the Coordination for the improvement of higher education personnel (CAPES) from Brazil. NK was funded through a competitive fellowship from Netaji-Subhas Indian Council of Agricultural Research (ICAR). MU was funded through competitive graduate fellowship from the Turkish Ministry of National Education. Some of the results from this study are presented at the SSR conference by Ugur et al. (14).

Methionine (Met) is an amino acid essential for many important cellular and biosynthetic functions, including the initiation of protein synthesis and S-adenosylmethionine-mediated methylation of proteins, RNA, and DNA. The de novo biosynthetic pathway of Met is well conserved across prokaryotes but absent from vertebrates, making it a plausible antimicrobial target. Using a systematic approach, we examined the essentiality of de novo methionine biosynthesis in Salmonella enterica serovar Typhimurium, a bacterial pathogen causing significant gastrointestinal and systemic diseases in humans and agricultural animals. Our data demonstrate that Met biosynthesis is essential for S. Typhimurium to grow in synthetic medium and within cultured epithelial cells where Met is depleted in the environment. During systemic infection of mice, the virulence of S. Typhimurium was not affected when either de novo Met biosynthesis or high-affinity Met transport was disrupted alone, but combined disruption in both led to severe in vivo growth attenuation, demonstrating a functional redundancy between de novo biosynthesis and acquisition as a mechanism of sourcing Met to support growth and virulence for S. Typhimurium during infection. In addition, our LC-MS analysis revealed global changes in the metabolome of S. Typhimurium mutants lacking Met biosynthesis and also uncovered unexpected interactions between Met and peptidoglycan biosynthesis. Together, this study highlights the complexity of the interactions between a single amino acid, Met, and other bacterial processes leading to virulence in the host and indicates that disrupting the de novo biosynthetic pathway alone is likely to be ineffective as an antimicrobial therapy against S. Typhimurium.