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AbstractA sustainable and reliable methodology to strengthen the mortar adhered to recycled concrete aggregate (RCA) is crucial for optimizing its utilization in construction. This research proposes a mortar strengthening method by soaking RCA in different dosages (weight percentages) of pozzolanic slurries, i.e., fly ash and silica powder (F-S), fly ash and cement (F-C), cement and silica powder (C-S) for various durations. The influence of each slurry dosage and soaking duration on RCA's physical and mechanical properties and surface morphology were examined. Further, a modified two-stage mixing approach (M-TSMA) was employed to produce recycled aggregate concrete (RAC) incorporating 100% untreated and surface-treated RCA. The impact of M-TSMA and treated RCA on concrete was demonstrated regarding its mechanical and durability properties, such as compressive strength, ultrasonic pulse velocity, rebound hammer, sorptivity, and resistance to chloride ions. Results show that soaking RCA in 30% C-S slurry for 6 h enhances RCA's overall properties by increasing the calcium silicate hydrate (C-S-H) content. Moreover, employing M-TSMA and incorporating treated RCA improves the mechanical and durability properties of RAC by reducing microcracks and densifying the microstructure. Overall, the proposed surface treatment and M-TSMA can potentially enhance RAC performance with complete RCA utilization. [ABSTRACT FROM AUTHOR]

SUMMARY Brassica carinata (BBCC) commonly referred to as Ethiopian mustard is a natural allotetraploid containing the genomes of Brassica nigra (BB) and Brassica oleracea (CC). It is an oilseed crop endemic to the northeastern regions of Africa. Although it is under limited cultivation, B. carinata is valuable as it is resistant/highly tolerant to most of the pathogens affecting widely cultivated Brassica species of the U's triangle. We report a chromosome‐scale genome assembly of B. carinata accession HC20 using long‐read Oxford Nanopore sequencing and Bionano optical maps. The assembly has a scaffold N50 of ~39.8 Mb and covers ~1.11 Gb of the genome. We compared the long‐read genome assemblies of the U's triangle species and found extensive gene collinearity between the diploids and allopolyploids with no evidence of major gene losses. Therefore, B. juncea (AABB), B. napus (AACC), and B. carinata can be regarded as strict allopolyploids. We cataloged the nucleotide‐binding and leucine‐rich repeat immune receptor (NLR) repertoire of B. carinata and, identified 465 NLRs, and compared these with the NLRs in the other Brassica species. We investigated the extent and nature of early‐generation genomic interactions between the constituent genomes of B. carinata and B. juncea in interspecific crosses between the two species. Besides the expected recombination between the constituent B genomes, extensive homoeologous exchanges were observed between the A and C genomes. Interspecific crosses, therefore, can be used for transferring disease resistance from B. carinata to B. juncea and broadening the genetic base of the two allotetraploid species. [ABSTRACT FROM AUTHOR]

S-nitrosylation is a well-known post-translational modification that modulates nitric oxide-dependent cell signaling. NADH-dependent S-nitrosoglutathione reductase (GSNOR) and NADPH-dependent thioredoxin reductase (NTR) enzymes are essential for nitric oxide/S-nitrosothiol (NO/SNO) homeostasis. GSNOR and NTR regulate denitrosylation by reducing S-nitrosoglutathione (GSNO) and thioredoxins, respectively. Genome-wide identification yielded 4 GSNOR and 12 NTR (4 each of NTRA, NTRB, and NTRC) genes in Brassica juncea. Syntenic relationship showed whole genome triplication (WGT) and tandem duplications. The phylogenetic analysis revealed clustering of BjGSNORs and BjNTRs with Arabidopsis homologs suggesting high sequence similarity within groups. Subcellular localization prediction suggested BjGSNOR localizes not only to the cytosol, but also to the Golgi apparatus and endoplasmic reticulum. BjNTRA and BjNTRB were localized in the cytoplasm and mitochondria, respectively, whereas BjNTRC localized in the chloroplast and nucleus. Several cis-acting elements involved in light responsiveness and expression analysis suggested the regulation of denitrosylation by light. The analysis of the promoter region also showed various phytohormone-regulated elements, suggesting the involvement of these enzymes in plant growth. Furthermore, GSNOR and NTR activities were higher in early growth stages. Differential spatial distributions of both the enzymes were observed with higher activity in hypocotyl in comparison with roots and cotyledons of the seedling. In flower, the highest activities were observed in carpel and least in stamens. Collectively, these findings provide an understanding of the structure, localization, and evolution of multiple copies of denitrosylases BjGSNOR and BjNTR, along with their possible roles in plant development. [ABSTRACT FROM AUTHOR]

The emergence of drug resistance in Mycobacterium tuberculosis (Mtb) is alarming and demands in-depth knowledge for timely diagnosis. We performed genome-wide association analysis using 2237 clinical strains of Mtb to identify novel genetic factors that evoke drug resistance. In addition to the known direct targets, we identified for the first time, a strong association between mutations in DNA repair genes and the multidrug-resistant phenotype. To evaluate the impact of variants identified in the clinical samples in the evolution of drug resistance, we utilized knockouts and complemented strains in Mycobacterium smegmatis and Mtb. Results show that variant mutations compromised the functions of MutY and UvrB. MutY variant showed enhanced survival compared with wild-type (Rv) when the Mtb strains were subjected to multiple rounds of ex vivo antibiotic stress. In an in vivo guinea pig infection model, the MutY variant outcompeted the wild-type strain. We show that novel variant mutations in the DNA repair genes collectively compromise their functions and contribute to better survival under antibiotic/host stress conditions. [ABSTRACT FROM AUTHOR]

Commonly, environmental processes are observed across different locations, and observations present skewed distributions. Recent proposals for analyzing data in their original scale, accommodating spatial structure and skewness, involve two independent Gaussian processes (GP). We focus on a skewed spatial process defined through a convolution of Gaussian and log Gaussian (GLGC) processes. Because of the inclusion of two GPs, the inference procedure quickly becomes challenging as the sample size increases. We aim to investigate how recently developed approximate GPs perform in modeling high-dimensional GLGC processes. Three methods are formulated based on the nearest neighbor (NN) and Hilbert space (HS) methods, and their performances are investigated in comparison with the exact inference using simulation studies. All the approximate methods yield results comparable to exact inference, but the HS-based method provides the fastest inference of moderate to very smooth processes. A hybrid approach incorporating NN and HS methods is preferred for faster inference with improved MCMC efficiency for a wiggly process.Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

The variations in mechanical properties of geopolymer concrete (GPC) prepared with treated recycled concrete aggregate (RCA) in conjunction with a modified two-stage mixing approach (M-TSMA (sp-ggbs)) have been studied in the present research. Since GPC is prepared using fly ash (FA) and ground granulated blast slag (GGBS) as an alternative to cement, it is sustainable and eco-friendly. Further, FA is partially replaced with silica powder (SP) to evaluate the mechanical properties of GPC. Additionally, RCA is treated with sodium silicate to strengthen the adhered mortar. Moreover, based on experimental results, Bayesian optimization Support Vector Regression (SVR) and Gaussian Process Regression (GPR) models are developed to predict the mechanical strengths of GPC mixtures. Results show that treating RCA with sodium silicate improves RCA's physical and mechanical characteristics. Furthermore, treated RCA and M-TSMA (sp-ggbs) enhance the mechanical strengths of GPC mixes, and these strengths can be accurately predicted using SVR and GPR models. • Examining the impact of silica powder on the properties of fly ash/GGBS-based GPC. • Sodium silicate (45 %, 7 days) enhances RCA's physical and mechanical properties. • Treated RCA and M-TSMA (sp-ggbs) improve the properties of ternary blend GPC. • Bayesian optimization algorithm tunes the hyperparameters of SVR and GPR models. • BOA-SVR and BOA-GPR models accurately predict the mechanical properties of GPC. [ABSTRACT FROM AUTHOR]

The strength and durability properties of the recycled aggregate concrete (RAC) have been affected by the cracks and the weak interfacial transition zone (ITZ) of the recycled coarse aggregates (RCA). However, the mechanical and physical features of RCA can be improved by microbially induced calcite precipitation (MICP). Therefore, immobilization techniques were used to protect and maintain the high efficiency of Bacillus bacteria for the formation and precipitation of calcium carbonates in self‐healing concrete over a period of time. The objective of the present study was to show the viability of the immobilized bacterial consortium‐enhanced RCA to form self‐healing cracks. Further, the self‐healing capability of enhanced RCA was investigated along with two other immobilization methods, that is, RCA and hydrated lime and brick powder (HBr)‐immobilized bacteria. The experimental results show that the increase in the bio‐deposition time improved the physical and mechanical properties of the RCA. Further, subsequently 56 days of the healing incubation period, the immobilized consortium‐enhanced RCA concrete specimens completely healed the cracks of width 0.58 mm. However, the equivalent cracks of width 0.56 mm were also recovered by the HBr immobilized bacterial cultures. Furthermore, the field emission scanning electron microscope (FESEM), energy dispersive spectroscopy (EDS) and X‐ray diffraction (XRD) analysis revealed that the existence of precipitation at the crack surface was calcium carbonate with a regular cubic‐shaped and lamellar layer morphology. The outcomes of the current study show that consortium‐enhanced RCA has promising potential to develop self‐healing concrete with self‐repaired and improved durability properties in the concrete construction field. [ABSTRACT FROM AUTHOR]

Summary: Brassica juncea (AABB), commonly referred to as mustard, is a natural allopolyploid of two diploid species—B. rapa (AA) and B. nigra (BB). We report a highly contiguous genome assembly of an oleiferous type of B. juncea variety Varuna, an archetypical Indian gene pool line of mustard, with ~100× PacBio single‐molecule real‐time (SMRT) long reads providing contigs with an N50 value of >5 Mb. Contigs were corrected for the misassemblies and scaffolded with BioNano optical mapping. We also assembled a draft genome of B. nigra (BB) variety Sangam using Illumina short‐read sequencing and Oxford Nanopore long reads and used it to validate the assembly of the B genome of B. juncea. Two different linkage maps of B. juncea, containing a large number of genotyping‐by‐sequencing markers, were developed and used to anchor scaffolds/contigs to the 18 linkage groups of the species. The resulting chromosome‐scale assembly of B. juncea Varuna is a significant improvement over the previous draft assembly of B. juncea Tumida, a vegetable type of mustard. The assembled genome was characterized for transposons, centromeric repeats, gene content and gene block associations. In comparison to the A genome, the B genome contains a significantly higher content of LTR/Gypsy retrotransposons, distinct centromeric repeats and a large number of B. nigra specific gene clusters that break the gene collinearity between the A and the B genomes. The B. juncea Varuna assembly will be of major value to the breeding work on oleiferous types of mustard that are grown extensively in south Asia and elsewhere. [ABSTRACT FROM AUTHOR]

Background: Brassica nigra (BB), also called black mustard, is grown as a condiment crop in India. B. nigra represents the B genome of U's triangle and is one of the progenitor species of B. juncea (AABB), an important oilseed crop of the Indian subcontinent. We report the genome assembly of B. nigra variety Sangam. Results: The genome assembly was carried out using Oxford Nanopore long-read sequencing and optical mapping. A total of 1549 contigs were assembled, which covered ~ 515.4 Mb of the estimated ~ 522 Mb of the genome. The final assembly consisted of 15 scaffolds that were assigned to eight pseudochromosomes using a high-density genetic map of B. nigra. Around 246 Mb of the genome consisted of the repeat elements; LTR/Gypsy types of retrotransposons being the most predominant. The B genome-specific repeats were identified in the centromeric regions of the B. nigra pseudochromosomes. A total of 57,249 protein-coding genes were identified of which 42,444 genes were found to be expressed in the transcriptome analysis. A comparison of the B genomes of B. nigra and B. juncea revealed high gene colinearity and similar gene block arrangements. A comparison of the structure of the A, B, and C genomes of U's triangle showed the B genome to be divergent from the A and C genomes for gene block arrangements and centromeric regions. Conclusions: A highly contiguous genome assembly of the B. nigra genome reported here is an improvement over the previous short-read assemblies and has allowed a comparative structural analysis of the A, B, and C genomes of the species belonging to the U's triangle. Based on the comparison, we propose a new nomenclature for B. nigra pseudochromosomes, taking the B. rapa pseudochromosome nomenclature as the reference. [ABSTRACT FROM AUTHOR]

Performance of a low temperature polymer electrolyte membrane fuel cell (PEMFC) is highly dependent on the kind of catalysts, catalyst supports, ionomer amount on the catalyst layers (CL), membrane types and operating conditions. In this work, we investigated the influence of membrane types and CL compositions on MEA performance. MEA performance increases under all practically relevant load conditions with reduction of the membrane thickness from 50 to 15 μm, however further decrease in membrane thickness from 15 to 10 μm leads to reduction in cell voltage at high current loads. A thick anode CL is found to be beneficial under wet operating conditions assuming more pore space is provided to accommodate liquid water, whereas under dry operating conditions, an intermediate thickness of the anode CL is beneficial. When studying the impact of catalyst layer thickness, too thin a catalyst layer again shows reduced performance due to increased ohmic resistance ruled out the performance of the MEAs which have identical Pt crystallite sizes on the cathode CLs i. e. the thinnest the cathode CL, the highest the voltage were achieved at a defined current load. Adaptation of the operating conditions is highly anticipated to achieve the highest MEA performance. [ABSTRACT FROM AUTHOR]

Background: Alternaria brassicae, a necrotrophic pathogen, causes Alternaria Leaf Spot, one of the economically important diseases of Brassica crops. Many other Alternaria spp. such as A. brassicicola and A. alternata are known to cause secondary infections in the A. brassicae-infected Brassicas. The genome architecture, pathogenicity factors, and determinants of host-specificity of A. brassicae are unknown. In this study, we annotated and characterised the recently announced genome assembly of A. brassicae and compared it with other Alternaria spp. to gain insights into its pathogenic lifestyle. Results: We also sequenced the genomes of two A. alternata isolates that were co-infecting B. juncea using Nanopore MinION sequencing for additional comparative analyses within the Alternaria genus. Genome alignments within the Alternaria spp. revealed high levels of synteny between most chromosomes with some intrachromosomal rearrangements. We show for the first time that the genome of A. brassicae, a large-spored Alternaria species, contains a dispensable chromosome. We identified 460 A. brassicae-specific genes, which included many secreted proteins and effectors. Furthermore, we have identified the gene clusters responsible for the production of Destruxin-B, a known pathogenicity factor of A. brassicae. Conclusion: The study provides a perspective into the unique and shared repertoire of genes within the Alternaria genus and identifies genes that could be contributing to the pathogenic lifestyle of A. brassicae. [ABSTRACT FROM AUTHOR]

Summary: Rapid intelligent transportation systems (ITS) innovations need a reliable MAC protocol to enable massive nonsafety message delivery and high‐priority safety broadcasts. The significant rise in spectrum need is regulated by collaboration in cognitive vehicular networks (CVNs). For QoS improvement, a reliable cooperative MAC for CVNs (CCVN‐MAC) is presented in this study. CCVN allows vehicles to collaborate and share channel status information, allowing for proactive channel switching in case of a legacy user (LU) appearance. To enable transmission mode selection, additional control signals are included. Using the suggested cooperative makeup technique, the helper nodes resend failed transmission. A Markov chain represents the protocol, and NS‐2 is used to evaluate it for several performance characteristics. Compared with conventional MAC techniques, the proposed protocol depicts improved performance, including depreciation of 70% in average latency and an increment of 42.4% in throughput. [ABSTRACT FROM AUTHOR]

[Display omitted] • A modified two-stage mixing approach (M-TSMA sp-ggbs) for RAC is developed. • Fresh and mechanical properties of RAC mixed with M-TSMA sp-ggbs are observed. • Two surface treatment methods i.e., HCl and Na 2 SiO 3 solution are used to treat RCA. • Mechanical properties of RAC containing treated RCA along with M-TSMA sp-ggbs. • SVR model opted to predict the mechanical strength considering experimental result. The present study aims to make the concrete prepared with recycled concrete aggregate (RCA) more sustainable by evaluating workability and mechanical strength, i.e., compressive, flexural, and splitting tensile strength of recycled aggregate concrete (RAC). In the present study, RCA is used as a replacement for natural coarse aggregate, and replacement is done by 20%, 40%, 60%, 80%, and 100%. In the context of making RAC more sustainable, a modified two-stage mixing approach (M-TSMA (sp-ggbs)) is adopted. In this mixing approach, cement is replaced by 10% of silica powder and ground granulated blast slag (GGBS) and mixed with water to prepare a slurry, in which RCA is added in the pre-mixing stage. It is observed that the mechanical properties of concrete are slightly improved. Further, to improve RCA characteristics, RCA treatment is done using two surface treatment solutions, HCl and Na 2 SiO 3 ; (a) RCA is soaked in three different molarities, i.e., 0.5 M, 1 M, and 1.5 M of HCl solution, for 1 and 7 days, and (b) RCA is soaked in 15%, 30%, and 45% concentrations of Na 2 SiO 3 solution for 1 and 7 days. The RCA showing the best characteristics regarding water absorption, impact, and crushing value is considered for preparing the concrete mix. Now, the treated RCA is used to prepare sustainable RAC in conjunction with M-TSMA (sp-ggbs). The experimental results show that the workability of all concrete mixes is within the desired range. Moreover, the mechanical properties are significantly improved by considering RCA treated with 45% concentrations of Na 2 SiO 3 soaked for 7 days at a 60% replacement level along with M-TSMA (sp-ggbs). Further, this article used support vector machine regression (SVR) to predict the compressive, flexural, and splitting tensile strength based on the experimental values and the input variables. The SVR model predicted the compressive, flexural, and splitting tensile strength with 97%, 95%, and 88% accuracy. [ABSTRACT FROM AUTHOR]

Anther and tapetum-specific genes are important for understanding male gametophyte development, as well as for their use in the development of barnase/barstar-gene based male sterility and restorer system for hybrid seed production. An essential component of the system is the availability of tapetum-specific promoters. In the present study, anther-specific genes were identified in cotton using microarray-based differential expression analysis, some of which show expression specific to the anthers at a stage where tapetum tissue was fully developed. Validation of the identified genes using RT-PCR and in situ hybridization identified one novel gene (AEG—Anther Expressing Gene) encoding a putative lipid binding protein as having a tapetum-specific expression. Further, three paralogs of the gene were identified in the cotton genome out of which the gene AEG1 (Anther Expressing Gene1) was found to express in the tapetum layer. Analysis of transgenic plants developed in cotton using 1.5 Kb promoter region of the of AEG1 gene fused upstream to the reporter gene β-glucuronidase revealed a broad window of expression of the AEG1 promoter in the tapetum tissue from the tetrad stage of anthers till the degeneration of the tapetum cells. Low levels of expression were also observed in the root tissues. Expression was not observed in the stem and leaves. The broad window of expression of AEG1 promoter in the tapetum tissue makes it a suitable candidate for the expression of the barstar gene for effective fertility restoration in the barnase/barstar system. [ABSTRACT FROM AUTHOR]

Following the publication of this article [1], the authors reported that the captions of Figs. 2 and 3 were published in the incorrect order, whereby they mismatch with their corresponding images. The figures are reproduced in the correct sequence with the correct captions in this Correction article. The original article has been corrected. [ABSTRACT FROM AUTHOR]

In this work the feasibility of a corrosion resistant non-carbon noble metal support for PEMFC cathode catalysts has been investigated and compared with a traditional carbon black support. We developed an antimony doped tin oxide (ATO) material which has reasonable electrical conductivity (0.7 S/cm) and surface area (50 m 2 /g). ATO and carbon black (CB) supported Platinum (Pt) electrocatalysts have been prepared by modifying the well-known polyol process. Electrochemical characterizations of the supported catalysts were done to measure the ECSA via cyclic voltammetry, ORR activity via RDE, Pt corrosion via load cycling, support corrosion via potential cycling and finally the catalysts were processed to MEAs for single cell performance tests. ATO supported catalyst showed improved corrosion resistance properties in 0.5 M H 2 SO 4 in three electrode system. However, lower performance than CB supported catalyst has been found after processing to MEAs for single cell tests at defined operating conditions. Electrochemical Impedance Spectroscopy has also been used as a diagnostic tool to asses MEA performance. [ABSTRACT FROM AUTHOR]

Transgenic cotton was developed using two constructs containing a truncated and codon-modified cry1Ac gene (1,848 bp), which was originally characterized from Bacillus thuringiensis subspecies kurstaki strain HD73 that encodes a toxin highly effective against many lepidopteran pests. In Construct I, the cry1Ac gene was cloned under FMVde, a strong constitutively expressing promoter, to express the encoded protein in the cytoplasm. In Construct II, the encoded protein was directed to the plastids using a transit peptide taken from the cotton rbcSIb gene. Genetic transformation experiments with Construct I resulted in a single copy insertion event in which the Cry1Ac protein expression level was 2–2.5 times greater than in the Bacillus thuringiensis cotton event Mon 531, which is currently used in varieties and hybrids grown extensively in India and elsewhere. Another high expression event was selected from transgenics developed with Construct II. The Cry protein expression resulting from this event was observed only in the green plant parts. No transgenic protein expression was observed in the non-green parts, including roots, seeds and non-green floral tissues. Thus, leucoplasts may lack the mechanism to allow entry of a protein tagged with the transit peptide from a protein that is only synthesized in tissues containing mature plastids. Combining the two events through sexual crossing led to near additive levels of the toxin at 4–5 times the level currently used in the field. The two high expression events and their combination will allow for effective resistance management against lepidopteran insect pests, particularly Helicoverpa armigera, using a high dosage strategy. [ABSTRACT FROM AUTHOR]

Key message: Genetic locus for tetralocular ovary ( tet - o ) in Brassica rapa was identified and it was shown that the number of locules and width of silique are associated. Abstract: Brassica rapa is a highly polymorphic species containing many vegetables and oleiferous types. An interesting group of oleiferous types is the yellow sarson group (subspecies trilocularis) grown mostly in eastern India. This group contains lines that have bilocular ovaries, a defining trait of Brassicaceae, but also lines that have tetralocular ovaries. Yellow sarson lines commonly have high silique width which is further enhanced in the tetralocular types. We mapped the locus influencing tetralocular ovary in B. rapa using three mapping populations (F, F and F) derived from a cross between Chiifu (subspecies pekinensis, having bilocular ovary) and Tetralocular (having tetralocular ovary). QTL mapping of silique width was undertaken using the three mapping populations and a F population derived from a cross between Chiifu and YSPB-24 (a bilocular line belonging to yellow sarson group). Qualitative mapping of the trait governing locule number ( tet- o) in B. rapa mapped the locus to linkage group A4. QTL mapping for silique width detected a major QTL on LG A4, co-mapping with the tet- o locus in bilocular/tetralocular cross. This QTL was not detected in the bilocular/bilocular cross. Saturation mapping of the tet- o region with SNP markers identified Bra034340, a homologue of CLAVATA3 of Arabidopsis thaliana, as the candidate gene for locule number. A C → T transition at position 176 of the coding sequence of Bra034340 revealed co-segregation with the tetralocular phenotype. The study of silique related traits is of interest both for understanding evolution under artificial selection and for breeding of cultivated Brassica species. [ABSTRACT FROM AUTHOR]

Background Brassica juncea (AABB) is an allotetraploid species containing genomes of B. rapa (AA) and B. nigra (BB). It is a major oilseed crop in South Asia, and grown on approximately 6-7 million hectares of land in India during the winter season under dryland conditions. B. juncea has two well defined gene pools - Indian and east European. Hybrids between the two gene pools are heterotic for yield. A large number of qualitative and quantitative traits need to be introgressed from one gene pool into the other. This study explores the availability of SNPs in RNA-seq generated contigs, and their use for general mapping, fine mapping of selected regions, and comparative arrangement of gene blocks on B. juncea A and B genomes. Results RNA isolated from two lines of B. juncea - Varuna (Indian type) and Heera (east European type) - was sequenced using Illumina paired end sequencing technology, and assembled using the Velvet de novo programme. A and B genome specific contigs were identified in two steps. First, by aligning contigs against the B. rapa protein database (available at BRAD), and second by comparing percentage identity at the nucleotide level with B. rapa CDS and B. nigra transcriptome. 135,693 SNPs were recorded in the assembled partial gene models of Varuna and Heera, 85,473 in the A genome and 50,236 in the B. Using KASpar technology, 999 markers were added to an earlier intron polymorphism marker based map of a B. juncea Varuna x Heera DH population. Many new gene blocks were identified in the B genome. A number of SNP markers covered single copy homoeologues of the A and B genomes, and these were used to identify homoeologous blocks between the two genomes. Comparison of the block architecture of A and B genomes revealed extensive differences in gene block associations and block fragmentation patterns. Conclusions Sufficient SNP markers are available for general and specific -region fine mapping of crosses between lines of two diverse B. juncea gene pools. Comparative gene block arrangement and block fragmentation patterns between A and B genomes support the hypothesis that the two genomes evolved from independent hexaploidy events. [ABSTRACT FROM AUTHOR]

Abstract: We investigated Salmonella enterica isolates from human clinical cases of gastroenteritis to determine the distribution of non-typhoidal Salmonella serovars in the human population, and compared them to isolates originating from poultry by serotyping, phage typing, plasmid profiling, pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) to evaluate the potential role of poultry in human non-typhoidal salmonellosis in Bangladesh. Nine different serovars were identified among the human isolates of which Salmonella Paratyphi B var Java (S. Java), S. Kentucky, S. Enteritidis, S. Virchow and S. Weltevreden also were commonly isolated from poultry. The poultry isolates belonging to S. Java, S. Kentucky and S. Enteritidis were indistinguishable from human isolates or genetically closely related, based on PFGE profiles and MLST. S. Kentucky clone ST198 and S. Java clone ST43 both well-known cause of human infections were also isolated from poultry. [Copyright &y& Elsevier]

Ribulose bis-carboxylase/oxygenase small subunit genes ( rbcS) are found to be highly expressed in most plant species. Promoters of rbcS genes have been isolated, characterized, and used to enhance expression of transgenes in transgenic lines. In this study, we have identified five different members of the rbcS gene family in cotton ( Gossypium hirsutum). All five genes contain three exons and two introns. Nucleotide sequences of the rbcS genes are conserved in their coding regions, but exhibit considerable sequence divergence in both introns and in upstream and downstream flanking sequences. Based on sequence identity, these genes are grouped into two subfamilies. Promoters of all rbcS genes have been isolated, and their cis-acting motifs, exhibiting different arrangements, have been identified. All five rbcS genes are differentially expressed in leaf and boll tissues of cotton plants at different stages of plant development. Three of the five isolated rbcS genes are found to be highly expressed in analyzed tissues. Multiple transcriptional start sites of all members of the gene family have been identified in leaf and boll tissues of cotton plants. Moreover, different members of the rbcS gene family from the two progenitor diploid species of G. hirsutum, namely, Gossypium herbaceum and Gossypium raimondii, have also been isolated to identify the lineage of the five rbcS genes. In addition, a total of three candidate promoters that can be used to enhance expression of transgenes in cotton have been identified. [ABSTRACT FROM AUTHOR]

Background: Brassica rapa (AA) contains very diverse forms which include oleiferous types and many vegetable types. Genome sequence of B. rapa line Chiifu (ssp. pekinensis), a leafy vegetable type, was published in 2011. Using this knowledge, it is important to develop genomic resources for the oleiferous types of B. rapa. This will allow more involved molecular mapping, in-depth study of molecular mechanisms underlying important agronomic traits and introgression of traits from B. rapa to major oilseed crops - B. juncea (AABB) and B. napus (AACC). The study explores the availability of SNPs in RNA-seq generated contigs of three oleiferous lines of B. rapa - Candle (ssp. oleifera, turnip rape), YSPB-24 and Tetra (ssp. trilocularis, Yellow sarson) and their use in genome-wide linkage mapping and specific-region fine mapping using a RIL population between Chiifu and Tetra. Results: RNA-seq was carried out on the RNA isolated from young inflorescences containing unopened floral buds, floral axis and small leaves, using Illumina paired-end sequencing technology. Sequence assembly was carried out using the Velvet de-novo programme and the assembled contigs were organised against Chiifu gene models, available in the BRAD-CDS database. RNA-seq confirmed the presence of more than 17,000 single-copy gene models described in the BRAD database. The assembled contigs and the BRAD gene models were analyzed for the presence of SSRs and SNPs. While the number of SSRs was limited, more than 0.2 million SNPs were observed between Chiifu and the three oleiferous lines. Assays for SNPs were designed using KASPar technology and tested on a F7-RIL population derived from a Chiifu x Tetra cross. The design of the SNP assays were based on three considerations - the 50 bp flanking region of the SNPs should be strictly similar, the SNP should have a read-depth of ≥7 and no exon/intron junction should be present within the 101 bp target region. Using these criteria, a total of 640 markers (580 for genome-wide mapping and 60 for specific-region mapping) marking as many genes were tested for mapping. Out of 640 markers that were tested, 594 markers could be mapped unambiguously which included 542 markers for genome-wide mapping and 42 markers for fine mapping of the tet-o locus that is involved with the trait tetralocular ovary in the line Tetra. Conclusion: A large number of SNPs and PSVs are present in the transcriptome of B. rapa lines for genome-wide linkage mapping and specific-region fine mapping. Criteria used for SNP identification delivered markers, more than 93% of which could be successfully mapped to the F7-RIL population of Chiifu x Tetra cross. [ABSTRACT FROM AUTHOR]

Here we have investigated theoretically the distribution of horizontally homogeneous pollutant concentration, when the fixed emission sources are taken as controls eith respect to time, such that the meansquare deviation of the pollutant concentration from the desired level (air quality standard) is minimised within the critical period over the entire boundary layer under impending adverse meteorological situation. [ABSTRACT FROM AUTHOR]

Stability of cathode catalyst support material is one of the big challenges of polymer electrolyte membrane fuel cells (PEMFC) for long term applications. Traditional carbon black (CB) supports are not stable enough to prevent oxidation to CO2 under fuel cell operating conditions. The feasibility of a graphitized carbon (GC) as a cathode catalyst support for low temperature PEMFC is investigated herein. GC and CB supported Pt electrocatalysts were prepared via an already developed polyol process. The physical characterization of the prepared catalysts was performed using transmission electron microscope (TEM), X-ray Powder Diffraction (XRD) and inductively coupled plasma optical emission spectrometry (ICP-OES) analysis, and their electrochemical characterizations were conducted via cyclic voltammetry(CV), rotating disk electrode (RDE) and potential cycling, and eventually, the catalysts were processed using membrane electrode assemblies (MEA) for single cell performance tests. Electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SEM) have been used as MEA diagonostic tools. GC showed superior stability over CB in acid electrolyte under potential conditions. Single cell MEA performance of the GC-supported catalyst is comparable with the CB-supported catalyst. A correlation of MEA performance of the supported catalysts of different Brunauer–Emmett–Teller (BET) surface areas with the ionomer content was also established. GC was identified as a promising candidate for catalyst support in terms of both of the stability and the performance of fuel cell. [ABSTRACT FROM AUTHOR]

Key message: BjuWRR1, a CNL-type R gene, was identified from an east European gene pool line of Brassica juncea and validated for conferring resistance to white rust by genetic transformation. White rust caused by the oomycete pathogen Albugo candida is a significant disease of crucifer crops including Brassica juncea (mustard), a major oilseed crop of the Indian subcontinent. Earlier, a resistance-conferring locus named AcB1-A5.1 was mapped in an east European gene pool line of B. juncea—Donskaja-IV. This line was tested along with some other lines of B. juncea (AABB), B. rapa (AA) and B. nigra (BB) for resistance to six isolates of A. candida collected from different mustard growing regions of India. Donskaja-IV was found to be completely resistant to all the tested isolates. Sequencing of a BAC spanning the locus AcB1-A5.1 showed the presence of a single CC-NB-LRR protein encoding R gene. The genomic sequence of the putative R gene with its native promoter and terminator was used for the genetic transformation of a susceptible Indian gene pool line Varuna and was found to confer complete resistance to all the isolates. This is the first white rust resistance-conferring gene described from Brassica species and has been named BjuWRR1. Allelic variants of the gene in B. juncea germplasm and orthologues in the Brassicaceae genomes were studied to understand the evolutionary dynamics of the BjuWRR1 gene. [ABSTRACT FROM AUTHOR]

The zoonosis anthrax caused by the bacterium Bacillus anthracis has a broad geographical distribution. Active enzootic areas are typically located away from central and northern Europe where cases of the disease occur only sporadically and in limited numbers. In contrast, a few out of the 64 districts of Bangladesh are hyper-endemic for anthrax and there the disease causes major losses in live-stock. In this study we genotyped eight strains of B. anthracis collected from the districts of Sirajganj and Tangail in 2013. All these strains belonged to canSNP group A.Br.001/002 Sterne differing only in a few of 31 tandem-repeat (MLVA)-markers. Whole genome sequences were obtained from five of these strains and compared with genomic information of B. anthracis strains originating from various geographical locations. Characteristic signatures were detected defining two “Bangladesh” clusters potentially useful for rapid molecular epidemiology. From this data high-resolution PCR assays were developed and subsequently tested on additional isolates from Bangladesh and Central Europe. Remarkably, this comparative genomic analysis focusing on SNP-discovery revealed a close genetic relationship between these strains from Bangladesh and historic strains collected between 1991 and 2008 in The Netherlands and Germany, respectively. Possible explanations for these phylogenetic relationships are discussed. [ABSTRACT FROM AUTHOR]

Irrational and inappropriate use of antibiotics in commercial chicken production can contribute to the development of antimicrobial resistance. We aimed to assess antibiotic usage in commercial chicken production in Bangladesh, and identify factors associated with this practice. We conducted a large-scale cross-sectional study to collect information on antibiotic usage in commercial chickens from January to May 2021. Structured interviews were conducted with 288 broiler, 288 layer and 192 Sonali (locally-produced cross-bred) farmers in 20 sub-districts across Bangladesh. The frequency of antibiotic usage, the types of antibiotics and purpose of usage were estimated for each production type. Adjusted odds ratios (aOR) were calculated to measure the association between antibiotic usage and factors related to the characteristics of the farms and farmers using multivariable logistic regression models. The proportion of farms, irrespective of their production type, reporting usage of antibiotics in the 24 hours preceding the interview was 41% (n = 314, 95% CI: 37–44%). Forty-five percent (n = 344, 41–48%) reported antibiotic usage in the last 72 hours, 86% (n = 658, 83–88%) in the last 14 days, and almost all farms, 98% (n = 753, 97–99%), had used antibiotics since the start of their production cycle. Use of antibiotics in the 24 hours preceding an interview was more frequently reported in broiler (OR 1.91, 95% CI: 1.36–2.69) and Sonali (OR 1.94, 95% CI: 1.33–2.33) than layer farms. Oxytetracycline (23–31%, depending on production type), doxycycline (18–25%), ciprofloxacin (16–26%) and amoxicillin (16–44%) were the most frequently used antibiotics. Antibiotics were reported to be used for both treatment and prophylactic purposes on most farms (57–67%). Usage of antibiotics in the 24h preceding an interview was significantly associated with the occurrence of any illnesses in chickens (aOR broiler: 41.22 [95% CI:13.63–124.62], layer: aOR 36.45[9.52–139.43], Sonali: aOR 28.47[4.97–162.97]). Antibiotic usage was mainly advised by veterinary practitioners (45–71%, depending on production type), followed by feed dealers (21–40%) and farmers (7–13%). Improvement of chicken health through good farming practices along with changes in key stakeholders (feed dealers and practitioners) attitudes towards antibiotic recommendations to farmers, may help to reduce the levels of antibiotic usage and thus contribute to mitigate antimicrobial resistance. [ABSTRACT FROM AUTHOR]

Objectives: We aimed at the identification of the association of comorbidities with the COVID-19 severity and hospitalization. Methods: It is a retrospective cross-sectional study to investigate the variation in age, sex, dwelling, comorbidities, and medication with the COVID-19 severity and hospitalization by enrolling 1025 recovered individuals while comparing their time of recovery with or without comorbidities. Results: COVID-19 patients mostly suffered from fever. The predominant underlying medical conditions in them were hypertension (HTN) followed by diabetes mellitus (DM). Patients with cardiovascular disease (CVD) (54.3%) and hepatic disorders (HD) (43.6%) experienced higher severity. The risk of symptomatic cases was higher in aged (odds ratio, OR = 1.04, 95% CI = 1.02–1.06) and comorbid (OR = 1.87, 95% CI = 1.34–2.60) patients. T-test confirmed the differences between the comorbid and non-comorbid patients’ recovery duration. The presence of multiple comorbidities increased the time of recovery (15–27 days) and hospitalization (20–40%). Increased symptomatic cases were found for patients having DM+HTN whereas CVD+Asthma patients were found with higher percentage of severity. Besides, DM+CKD (chronic kidney disease) was associated with higher hospitalization rate. Higher odds of severity were found for DM+CVD (OR = 4.42, 95% CI = 1.81–10.78) patients. Hospitalization risk was also increased for them (OR = 5.14, 95% CI = 2.02–13.07). Moreover, if they had HTN along with DM+CVD, they were found with even higher odds (OR = 6.82, 95% CI = 2.37–19.58) for hospitalization. Conclusion: Our study indicates that people who are aged, females, living in urban area and have comorbid conditions are at a higher risk for developing COVID-19 severity. Clinicians and health management authorities should prioritize these high-risk groups to reduce mortality attributed to the disease. [ABSTRACT FROM AUTHOR]

Background: The emergence of methicillin‐resistant Staphylococcus aureus (MRSA) and methicillin‐resistant Staphylococcus pseudintermedius (MRSP) have a significant health impact on people with direct or supportive occupations in veterinary medicine including veterinarians, animal handlers, laboratory personnel and pet owners. Objectives: This cross‐sectional survey was conducted to determine the prevalence of and risk factors for S. aureus, S. pseudintermedius, MRSA and MRSP in dogs in Bangladesh. Methods: A total of 358 swab samples were collected from different body sites of 150 dogs attending a university teaching veterinary hospital between January and June 2018. Standard bacteriological procedures were followed to isolate Staphylococcus, and identification was confirmed to the species level by PCR to detect the nuc gene. MRSA and MRSP were confirmed by the presence of the mecA gene. Results: The prevalence of coagulase‐positive S. aureus and S. pseudintermedius in dogs were 16% and 45.3%, respectively. S. aureus and S. pseudintermedius isolates displayed the highest resistance against nalidixic acid (95.2% and 91%, respectively) and erythromycin (89.3% and 84.7%, respectively). Notably, all the staphylococcal isolates showed resistance to ≥3 antimicrobial classes. The prevalence of MRSA and MRSP in dogs was 8.7% and 6%, respectively. Multivariable logistic regression analysis identified the following variables as risk factors for MRSA colonisation in dogs: dogs with dermatitis (odds ratio [OR], 12.24, 95% CI: 3.12–57.33; p < 0.001) and history of antibiotic use (OR 8.73, 95% CI: 2.23–43.10; p < 0.001). Presence of otitis (OR 14.22; 95% CI: 1.64–103.58; p = 0.008) and oral lesions (OR 9.48, 95% CI: 1.14–64.82; p = 0.002) were identified as the significant risk factors for the carriage of MRSP. Conclusions: The circulation of multidrug‐resistant S. aureus and S. pseudintermedius is a serious concern to dogs and humans. To our knowledge, this is the first report of S. pseudintermedius and MRSP affecting dogs in Bangladesh. [ABSTRACT FROM AUTHOR]

Background: Salmonella is frequently found in poultry of which only motile serovars have zoonotic significance due to their potential to induce human gastrointestinal infections. Antimicrobial resistance, being a public health concern, the emergence of multidrug‐resistant (MDR) Salmonella serotypes affecting food chain has greater impact worldwide. Aim: Information on circulation of zoonotic Salmonella strains in commercial poultry farm level is limited in many parts of the world. This cross‐sectional study was aimed to investigate the zoonotic Salmonella strains circulating in the broiler farm environment with their detailed antimicrobial resistance profiling. Methods: Pooled faecal samples were collected randomly from commercial broiler farms of Chattogram district, Bangladesh. Standard bacteriological procedure was followed to isolate Salmonella, and identification was confirmed by genus specific polymerase chain reaction (PCR). After phenotypic characterisation of resistance profile against eight antimicrobials by disc diffusion technique, all strains were screened by PCR for some selected resistance genes. Results: Out of the 350 samples, Salmonella was isolated and identified from 86 samples. In antimicrobial sensitivity testing, more than 98.8% isolates showed resistance to ampicillin and 94.2% to tetracycline followed by enrofloxacin (56%) and ciprofloxacin (50%). Notably, 94% isolates were found to be MDR. The results of PCR assays revealed that 81.4% of the isolates were carrying the tetA gene, 19.8% the tetB and 10.47% the tetC gene. The prevalence of the isolates bearing the blaTEM, blaCTX‐M and Sul‐I gene were 95.4%, 7.0 % and 37.2 %, respectively. Conclusion: There is a great risk to secure healthy poultry products due to the circulation of these MDR zoonotic Salmonella [ABSTRACT FROM AUTHOR]

Aims: Antimicrobial resistance (AMR) spreads not only by pathogenic but also by commensal bacteria, and the latter can become a reservoir for resistance genes. This study was aimed to investigate the AMR patterns along with the presence of mobilized colistin resistance (mcr) genes in commensal Escherichia coli circulating in chickens, farm environments, street foods, and human patients. Materials and Methods: By a cross-sectional survey, isolates obtained from 530 samples were tested for their AMR profiles against 9 antimicrobials. Minimum inhibitory concentration (MIC) of the phenotypically colistin-resistant isolates was determined and screened for a set of mcr genes followed by sequencing of mcr-1 gene in the multidrug-resistant (MDR) isolates. Results: A total of 313 E. coli strains were isolated and confirmed by polymerase chain reaction. Antimicrobial susceptibility testing revealed that about 98% (confidence interval [95% CI] 95–99) of the isolates were MDR, and 58% (95% CI 52–63) isolates exhibited resistance to colistin. MIC values of colistin against the isolates ranged from 4 to 64 mg/L. Except for human patients, 20.4% colistin-resistant isolates from other sources of isolation had mcr-1 gene. Conclusions: There is abundance of commensal MDR E. coli strains with the acquisition of mcr-1 gene circulating in chickens and farm environments in Bangladesh. [ABSTRACT FROM AUTHOR]

Live animal markets are known hotspots of zoonotic disease emergence. To mitigate those risks, we need to understand how networks shaped by trading practices influence disease spread. Yet, those practices are rarely recorded in high-risk settings. Through a large cross-sectional study, we assessed the potential impact of live poultry trading networks' structures on avian influenza transmission dynamics in Bangladesh. Networks promoted mixing between chickens sourced from different farming systems and geographical locations, fostering co-circulation of viral strains of diverse origins in markets. Viral transmission models suggested that the observed rise in viral prevalence from farms to markets was unlikely explained by intra-market transmission alone, but substantially influenced by transmission occurring in upstream network nodes. Disease control interventions should therefore alter the entire network structures. However, as networks differed between chicken types and city supplied, standardised interventions are unlikely to be effective, and should be tailored to local structural characteristics. [ABSTRACT FROM AUTHOR]

A nursery comprising 25 elite bread wheat genotypes were evaluated to identify the sources of resistance to wheat blast caused by Magnaporthe oryzae pathotype Triticum (MoT), under artificial and natural infection experiments in three consecutive years from 2018 to 2020 in two different locations of Bangladesh. Seedling evaluation results revealed the absence of resistant and most genotypes displayed moderately susceptible to susceptible reaction. In the adult-plant field testing, six genotypes namely Borlaug 100, BARI Gom 33, BAW 1272, BAW 1280, BAW 1286, and BAW 1297 consistently showed resistant response to wheat head blast (WHB) infection with low levels of disease severity ranging from 0.2 to 8.1%. Among the remaining genotypes, some were moderately resistant, and the others exhibited various levels of susceptibility. The resistant genotypes that were most promising showed good agronomic performance under inoculated field trials. A significant positive correlation was observed between seedling and adult plant resistance. The above mentioned six genotypes also showed resistant reaction to WHB infection under controlled conditions when tested with three selected MoT isolates. The presence of 2NS/2AS translocation conferring WHB resistance was confirmed in four of the tested genotypes. Three (BAW 1272, BAW 1286, and BAW 1297) lines having non-2NS background exhibited good blast resistance under both the field and controlled conditions. These results will be useful for breeders and pathologists in exploiting the 2NS and non-2NS based resistant sources to pyramid and develop broad genetic based resistant germplasm. [ABSTRACT FROM AUTHOR]

Magnaporthe oryzae pathotype Triticum (MoT) was shown for the first time to cause barley blast in Bangladesh after distinct partially or fully bleached heads were observed in barley fields in Jashore and Meherpur in April 2019. The fungus isolated from diseased spikes was identified as Magnaporthe oryzae based on conidial morphology. MoT was confirmed based on results of ITS sequencing and a MoT3-specific molecular marker assay. Symptoms identical to those in the field were developed on leaves and spikes inoculated with the isolate. [ABSTRACT FROM AUTHOR]

Durum wheat (Triticum turgidum var. durum Desf.) is an important cereal crop in many regions of the world. In March of 2018 and 2019, symptoms typical of blast were frequently observed on durum wheat plants under field conditions in Jashore, Bangladesh. The putative causal pathogen was isolated from infected wheat spike specimens onto potato dextrose agar and oatmeal agar, and was identified from mono-conidium cultures as Magnaporthe oryzae, based on morphological features. The pathotype of the fungus was identified as Triticum, based on comparative molecular analyses of ITS sequences and MoT3 specific markers. BLAST analysis revealed >99.8% similarity with M. oryzae/P. oryzae, retrieved from the NCBI Genebank. This was confirmed through amplification of the predicted products with MoT3 primers in PCR analysis. Pathogenicity was confirmed by inoculating healthy durum wheat seedling leaves and spikes with a conidium suspensions of M. oryzae isolate DuBWMRI1901.2A. The fungus produced similar symptoms on inoculated leaves and spikes as those observed in the field, and was subsequently re-isolated, fulfilling Koch's postulates. This is the first report of blast of durum wheat caused by Magnaporthe oryzae pathotype Triticum in Bangladesh. [ABSTRACT FROM AUTHOR]

Symptoms of partially bleached and completely white heads were observed in a triticale (× Triticosecale) cultivar 'BARI Triticale 1ʹ in the research plots at the Regional Agricultural Research Station, Jashore, Bangladesh, during April 2019. Foliar symptoms with elliptical or eye-shaped lesions were also found on plant leaves. The main intention of this study was to isolate and identify the causal organism of the disease. Morphological characteristics of the pathogen showed the presence of pyriform 2-septate hyaline conidia and coloured conidiophores, indicating the presence of the fungus Magnaporthe oryzae. Molecular analyses by ITS sequence analysis and amplification of the product with MoT3 primers confirmed the identity of the fungus as M. oryzae pathotype Triticum. The pathogenicity of the representative isolates was confirmed by inoculation of triticale heads and leaves under laboratory conditions, resulting in similar symptoms as observed in the field. To our knowledge, this is the first report of triticale blast caused by M. oryzae pathotype Triticum in Bangladesh. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the performance of different fungicides (chemical, botanical and bio-agent) against wheat blast under field conditions and to identify the best one for preventive spray. Among the fungicides evaluated, Nativo 75 WG (Tebuconazole 50% + Trifloxystrobin 25%), Amistar Top 325 SC (Azoxystrobin 20% + Difenoconazole 12.5%) and Cabrio Top 60 WG (Pyraclostrobin 5% + Metiram 55%) demonstrated the best results with least blast severity (4–8%) and the highest yield (78–88%). It was concluded that the mentioned fungicides can be used to control wheat head blast by spraying twice at 13–15 days interval starting with the heading stage. [ABSTRACT FROM AUTHOR]

Background: Quality and microbial safety of milk is demanding day by day as it is considered as a host for pathogenic and spoilage microorganisms. In this study, isolation and molecular characterization of shigatoxigenic O157 and non-O157 Escherichia coli in raw milk marketed in Chittagong, Bangladesh were done on 186 raw milk samples in Bangladesh. Methods: MacConkey agar was initially used to screen for the presence of E. coli and the suspected growth as evidenced by large pink colonies on MacConkey agar. Finally the organism was verified by plating through Eosin Methylene Blue (EMB) agar (a selective medium for E. coli where it produces metallic sheen) and applying standard biochemical tests for E. coli. The presence of virulent genes, Shiga-like toxin (stx1 and stx2), Intimin (eaeA), O157 antigen rfbE and Enterohemorrhagic Escherichia coli (EHEC) Hemolysin (EHEC) hlyA in the contaminating E. coli population was determined by polymerase chain reaction (PCR) run on a thermocycler (Applied Biosystem, 2720 thermal cycler, Singapore). Result: Among the raw milk samples, 33 samples were identified as E.coli positive and among the isolates, 6 (18.18%) were identified as possible EHEC O157 and rest of the isolates (81.82%) were considered as probable non EHEC O157. About, 3.23% (186 samples) EHEC O157 was isolated from raw milk samples. Then all the 33 isolates were taken under PCR assay for the identification of five virulent genes Stx1, Stx2, eaeA, rfbE and hlyA. No virulent genes were found in non-EHEC O157 isolates, but 4 stx2 (66.67%) and 1 hlyA (16.67%) gene were observed in another 4 EHEC O157 isolates out of 6, but one isolates contained the both genes and hence the prevalence of STEC was 2.15% in raw milk. Result indicated poor hygienic standard of raw milk from uncontrolled environments and the increased public health risk of those consuming raw milk from such uncontrolled sources. [ABSTRACT FROM AUTHOR]

Background and Aim: The emergence of antimicrobial resistance (AMR) in commensal organism, such as Escherichia coli of food animals, is an alarming issue for global health. It increases the possibility of transmitting AMR determinant(s) to human bacterial pathogens by transferable genetic materials, particularly by plasmids. Hence, it is important to know which resistant genes are being carried by commensal organisms in food chain in a country and their level of temporal loads. As a result, pre-emptive measures can be advocated with an aim to reduce their risks in their primary source of circulation which consequently would benefit the public health. Materials and Methods: Commensal E. coli strains from broiler chickens on randomly selected 30 farms and the farm environments were examined for the frequencies of isolation of resistant strains to oxytetracycline and ciprofloxacin. Five birds were randomly selected from each farm to collect cloacal swab samples (total of 150 samples). Furthermore, a total of 150 environmental samples comprising one each from feed, water, soil, litter, and litter damping site of each farm were screened for the isolation of commensal E. coli strains. Strains thus obtained were initially tested for their resistance to oxytetracycline and ciprofloxacin by Kirby-Bauer disk diffusion method. Oxytetracycline-resistant strains were further screened for the presence of resistance determining genes, namely, tetA, tetB, and tetC by uniplex polymerase chain reactions. Risks associated with the isolation frequency of oxytetracycline- and ciprofloxacin-resistant E. coli were also assessed by univariable logistic regression analysis. Results: The results revealed that all E. coli isolates, regardless of the source of origin, were resistant to oxytetracycline, while 78.4% (95% confidence interval [CI] 69.1-85.5%) showed resistance to ciprofloxacin. All the randomly selected (20) oxytetracycline-resistant strains harbored the tetA gene, whereas tetB and tetC were reported in three and two isolates, respectively. After univariable analysis, only one variable, that is, strain 1 of broiler chickens compared to two other strains was found to be positively associated with the isolation of ciprofloxacin-resistant E. coli (odds ratio 12.75 [95% CI 1.0- 157.1], p=0.047). Conclusion: Resistance emerged against oxytetracycline and ciprofloxacin in commensal E. coli strains circulating in live poultry and farm environments in Bangladesh seems to be very high. Thus, human infection with drug-resistant E. coli strains through food chain will critically compromise the therapeutic measures currently available. [ABSTRACT FROM AUTHOR]

Aims: To investigate plasmid-borne colistin resistance mechanism (plasmid-mediated colistin resistance [mcr-1]) in Escherichia coli of human, veterinary, and environmental origin in Bangladesh. Materials and methods: A total of 810 samples were collected from different sources. Isolation and identification of E. coli was performed using classical bacteriology and then tested for antimicrobial susceptibility. Colistin-resistant isolates were further analyzed for mcr-1 gene using PCR. Minimum inhibitory concentration (MIC) was determined using microbroth dilution technique. After sequencing of mcr-1 gene, phylogenetics was conducted to see the relationship with other mcr-1 gene sequences. Results: A total of 358 E. coli were isolated from 810 samples of humans, animals, environment, and food in Bangladesh. Of them 49 (15.9%) isolates were phenotypically resistant to colistin and 254 (70.9%) were resistant to multiple antimicrobials. mcr-1 gene was detected in three E. coli isolates of poultry source. For the three mcr-1 positive isolates the MIC of colistin sulfate was 4, 8, and 128 μg/mL. Gene sequencing of two of the three mcr-1 positive isolates and phylogenetic analysis showed close similarities of one isolate to other mcr-1 sequences available at GenBank while the other appeared to have evolved locally. Conclusion: First-ever report on circulation of mcr-1 E. coli of livestock origin in Bangladesh. [ABSTRACT FROM AUTHOR]

Irrawaddy squirrel (Callosciurus pygerythrus) may play an important role in the transmission of zoonotic bacteria, but little is known about the carriage of zoonotic bacteria in this common frugivorous rodent in Bangladesh. We aimed to investigate the presence of common zoonotic bacterial pathogens in Irrawaddy squirrel in the southeast part of Bangladesh. A total of 27 rectal and 27 oro‐nasal swabs were collected from 27 healthy wild Irrawaddy squirrels. Four common zoonotic bacteria were isolated following routine laboratory procedures, and were identified based on colony morphology, and biochemical and staining properties. The pathogenic potential of the identified bacteria was confirmed by detection of virulence genes by PCR. All isolates were subjected to antimicrobial susceptibility test against seven antibiotics from six generic groups which are commonly used in human and veterinary medicine in Bangladesh. The prevalence of Escherichia coli, Salmonella spp., Yersinia spp. and Staphylococcus spp. was 44.4% (95% CI, 32.0–57.6), 13% (95% CI, 6.1–24.7), 44.4% (95% CI, 32.0–57.6), and 72.2% (95% CI, 59.0–82.5), respectively. We identified potential zoonotic virulence genes in all of these four bacterial species. Antimicrobial susceptibility testing revealed the presence of several multidrug resistant bacterial strains in squirrels. To the best of our knowledge, this is the first report in Bangladesh of the detection of antibiotic resistant zoonotic bacteria in Irrawaddy squirrels. The findings underpin the role of Irrawaddy squirrel as a source of pathogenic antibiotic resistant bacteria, consequently, fruit rejected because of squirrel consumption and squirrel‐bites deserve more concern than previously. [ABSTRACT FROM AUTHOR]

Background: Though hyponatraemia is a common scenario in our daily clinical practice, the mortality and morbidity are very high without early detection and prompt treatment. Both under and over treatment of hyponatraemia may cause permanent brain damage. Proper and meticulous treatment may prevent development of permanent brain disorder. So, a study was carried out to see the prevalence of hyponatraemia in acute confusional states and coma. The effect of hyponatraemia on consciousness level was also observed. Materials & Methods: A cross sectional study. Results: A total number of sixty (60) cases with acute confusional state and coma were recruited in our study. Among 60 patients with acute confusional states including coma, 85% (51) patients were presented with hyponatraemia. In the study, mild, moderate and severe hyponatraemia were 20%, 13.33% and 51.67% respectively. Of the total study population, 31.67%, 33.33% and 35% presented with coma, stupor and drowsiness respectively. Severe hyponatraemia was found in 68.42% in comatose, 50% in stuporous and 38.1% in drowsy patients. 47.06% of hyponatraemic patients were noticed in several intracranial disorders. Hepatic encephalopathy, gastrointestinal disorders, chronic renal failure and ischemic heart disease comprised 13.73%, 11.76%, 9.80% and 5.89% respectively. Diabetic ketoacidosis and hypoglycaemic shock comprised 3. 92% each and congestive heart failure and acute respiratory distress syndrome comprised 1.96% each of hyponatraemic patients. Conclusions: Hyponatraemia is a common clinical problem in our day to day clinical practice. If neglected this may result in permanent brain malfunction which may be prevented with earlier detection and correction under meticulous supervision. [ABSTRACT FROM AUTHOR]

New biotic stresses have emerged around the globe over the last decades threatening food safety and security. In 2016, scientists confirmed the presence of the devastating wheat-blast disease in Bangladesh, South Asia–its first occurrence outside South America. Severely blast-affected wheat fields had their grain yield wiped out. This poses a severe threat to food security in a densely-populated region with millions of poor inhabitants where wheat is a major staple crop and per capita wheat consumption has been increasing. As an ex ante impact assessment, this study examined potential wheat-blast scenarios in Bangladesh, India, and Pakistan. Based on the agro-climatic conditions in the epicenter, where the disease was first identified in Bangladesh in 2016, this study identified the correspondingly vulnerable areas in India, Pakistan and Bangladesh amounting to 7 million ha. Assuming a conservative scenario of 5–10% for blast-induced wheat production loss, this study estimated the annual potential wheat loss across the sampled countries to be 0.89–1.77 million tons, equivalent to USD 132–264 million. Such losses further threaten an already-precarious national food security, putting pressure on wheat imports and wheat prices. The study is a call for action to tackle the real wheat-blast threat in South Asia. [ABSTRACT FROM AUTHOR]

In Bangladesh, anthrax, caused by the bacterium Bacillus anthracis, is considered an endemic disease affecting ruminants with sporadic zoonotic occurrences in humans. Due to the lack of knowledge about risks from an incorrect removal of infected carcasses, the disease is not properly monitored, and because of the socio-economic conditions, the situation is under-reported and under-diagnosed. For sensitive species, anthrax represents a fatal outcome with sudden death and sometimes bleeding from natural orifices. The most common source of infection for ruminants is ingestion of spores during grazing in contaminated pastures or through grass and water contaminated with anthrax spores. Domestic cattle, sheep and goats can also become infected through contaminated bone meal (used as feed) originating from anthrax-infected carcasses. The present investigation was conducted to isolate B. anthracis organisms from 169 samples (73 soil, 1 tissue, 4 bone and 91 bone meal samples) collected from 12 different districts of Bangladesh. The sampling was carried out from 2012 to 2015. Twelve samples resulted positive for B. anthracis. Biomolecular analyses were conducted starting from the Canonical Single Nucleotide Polymorphism (CanSNP) to analyze the phylogenetic origin of strains. The analysis of genotype, obtained through the Multiple Locus Variable Number Tandem Repeat Analysis (MLVA) with the analysis of 15 Variable Number Tandem Repeats (VNTR), demonstrated four different genotypes: two of them were previously identified in the district of Sirajganj. The sub-genotyping, conducted with Single Nucleotide Repeats analysis, revealed the presence of eight subgenotypes. The data of the present study concluded that there was no observed correlation between imported cattle feed and anthrax occurrence in Bangladesh and that the remarkable genetic variations of B. anthracis were found in the soil of numerous outbreaks in this country. [ABSTRACT FROM AUTHOR]

Objective Comparative evaluation of 2% hydroquinone, 0.025% tretinoin and 1% mometasone versus glycolic acid and trichloroacetic acid peel alone in melasma. Methods Seventy five patients were included in the study. Total duration of study was one and a half years. Melasma area severity index (MASI) score of more than 10 were included in the study. The patients were divided into three groups. Group A consisted of 25 patients and were given 2% Hydroquinone, mometasone 1% and 0.025% tretinoin. Group B consisted of 25 patients and underwent glycolic acid peel. Group C consisted of 25 patients and underwent trichloroacetic acidpeel. Results Group A had better response, followed by group B and group C, respectively. Conclusion Combination of hydroquinone, mometasone and tretinoin is a good option to treat melasma only when used judiciously along with sunscreen, whereas glycolic acid peels are a safer option with fewer side effects. [ABSTRACT FROM AUTHOR]

Background: Climate change affects human health by altering the proliferation and distribution of pathogen, vectors and allergen. Objective: To estimate the magnitude of climate related diseases in coastal areas in contrast to the plain area and also to determine their relationship with environmental factors. Methods: This prospective cross sectional study was conducted in southern part of Bangladesh from April 2012 to March 2013. Two Upazilla for this study were Dakope in coastal area and Terokhada in plain area. Patients of all ages attending the Upazilla Health Complex (UHC) with target diseases were enrolled. Nine target diseases were: water borne (diarrhea, typhoid, viral hepatitis); vector borne (malaria, kalazar, dengue) and systemic diseases (asthma, hypertension, arsenicosis). Results: Target diseases were observed in 1042 patients in Dakope and 1296 cases in Terokhada. Diseases were lowest (20%) in monsoon and highest in winter (42%). Large bulk of patients (31-32%) in both areas was young adult (16-30 years). Diarrhoea was highest (49-53%) in frequency in both areas. A few case of dengue (1%) in Dakope and kala-azar (2%) in Terokhada was found. Hypertension (19% Vs 13%) in Dakope and asthma (11% Vs 16%) in Terokhada was more frequent. Diarrhoea, was significantly higher (p<0.001) in patients with pond water consumption. Bushes/ditches (47%) were more prevalent in dengue prone area and cattleshed/poultry (55%) in kala-azar affected area. Conclusion: Diarrhoea, dengue and hypertension were more frequent in coastal area, conversely kala-azar, asthma was more common in plain area. Water consumption, environment and economy had significant influences over them. [ABSTRACT FROM AUTHOR]

Streptococcus zooepidemicushas recently been shown to be a severe pathogen in layer chickens, where it is able to cause serious lesions in the vascular system. To evaluate the haemostatic response, 10 layer chickens were inoculated intravenously withS. zooepidemicus. Four hypotheses were tested: that the infection-induced inflammation would increase the plasma fibrinogen (Fbg) concentration, would prolong the prothrombin time (PT) and would prompt hypercoagulability or hypocoagulability as assessed by whole-blood thromboelastography (TEG), and that a possible correlation would exist between one of the TEG values and Fbg/PT. Each parameter was measured at days 1, 3 and 6 post inoculation (p.i.), and compared with the values at day 0 from each individual bird and with values obtained from non-infected control chickens (n= 10). In the infected chickens, the mean (± standard error) of Fbg was higher at day 3 p.i. (9.4 ± 1.4 g/l) and day 6 p.i. (8.0 ± 0.7 g/l) and the PT was prolonged at day 6 p.i. (168.1 ± 21.0 sec) compared with the day 0 standards (2.6 ± 0.2 g/l and 104.6 ± 2.0 sec, respectively) (P< 0.05). The majority of infected chickens demonstrated a hypercoagulable TEG result with increased mean values of the clot formation rate (α-angle) and maximal amplitude (MA) of TEG tracing at day 3 p.i. (83.1 ± 0.7°, 83.8 ± 1.4 mm) and day 6 p.i. (84.0 ± 0.4°, 89.8 ± 1.0 mm) compared with the day 0 values (75.8 ± 2.2° and 66.9 ± 1.4 mm, respectively) (P< 0.05). In control birds, the means of Fbg (1.5 ± 0.1 g/l), PT (79.4 ± 6.4 sec), TEG-α(76.7 ± 1.5°) and TEG-MA(64.0 ± 2.3 mm) were lower at day 6 compared with values observed for the infected chickens (P< 0.05). A negative correlation coefficient (−0.71) was found between the clot formation time (TEG-K) and Fbg at day 1 in the control group (P= 0.02). In conclusion, infection withS. zooepidemicusfollowing intravenous injection in layer chickens induced haemostatic alterations including hyperfibrinogenaemia, prolonged PT, and hypercoagulability as measured by increased TEG-αand TEG-MA. [ABSTRACT FROM AUTHOR]

Background: Escherichia coli O157 (EcO157) infection has been recognized as an important global public health concern. But information on the prevalence of EcO157 in cattle at the global and at the wider geographical levels is limited, if not absent. This is the first meta-analysis to investigate the point prevalence of EcO157 in cattle at the global level and to explore the factors contributing to variation in prevalence estimates. Methods: Seven electronic databases- CAB Abstracts, PubMed, Biosis Citation Index, Medline, Web of Knowledge, Scirus and Scopus were searched for relevant publications from 1980 to 2012. A random effect meta-analysis model was used to produce the pooled estimates. The potential sources of between study heterogeneity were identified using meta-regression. Principal findings: A total of 140 studies consisting 220,427 cattle were included in the meta-analysis. The prevalence estimate of EcO157 in cattle at the global level was 5.68% (95% CI, 5.16–6.20). The random effects pooled prevalence estimates in Africa, Northern America, Oceania, Europe, Asia and Latin America-Caribbean were 31.20% (95% CI, 12.35–50.04), 7.35% (95% CI, 6.44–8.26), 6.85% (95% CI, 2.41–11.29), 5.15% (95% CI, 4.21–6.09), 4.69% (95% CI, 3.05–6.33) and 1.65% (95% CI, 0.77–2.53), respectively. Between studies heterogeneity was evidenced in most regions. World region (p<0.001), type of cattle (p<0.001) and to some extent, specimens (p = 0.074) as well as method of pre-enrichment (p = 0.110), were identified as factors for variation in the prevalence estimates of EcO157 in cattle. Conclusion: The prevalence of the organism seems to be higher in the African and Northern American regions. The important factors that might have influence in the estimates of EcO157 are type of cattle and kind of screening specimen. Their roles need to be determined and they should be properly handled in any survey to estimate the true prevalence of EcO157. [ABSTRACT FROM AUTHOR]

Brassica species (tribe Brassiceae) belonging to U's triangle—B. rapa (AA), B. nigra (BB), B. oleracea (CC), B. juncea (AABB), B. napus (AACC) and B. carinata (BBCC)—originated via two polyploidization rounds: a U event producing the three allopolyploids, and a more ancient b genome-triplication event giving rise to the A-, B-, and C-genome diploid species. Molecular mapping studies, in situ hybridization, and genome sequencing of B. rapa support the genome triplication origin of tribe Brassiceae, and suggest that these three diploid species diversified from a common hexaploid ancestor. Analysis of plastid DNA has revealed two distinct lineages—Rapa/Oleracea and Nigra—that conflict with hexaploidization as a single event defining the tribe Brassiceae. We analysed an R-block region of A. thaliana present in six copies in B. juncea (AABB), three copies each on A- and B-genomes to study gene fractionation pattern and synonymous base substitution rates (Ks values). Divergence time of paralogues within the A and B genomes and homoeologues between the A and B genomes was estimated. Homoeologous R blocks of the A and B genomes exhibited high gene collinearity and a conserved gene fractionation pattern. The three progenitors of diploid Brassicas were estimated to have diverged approximately 12 mya. Divergence of B. rapa and B. nigra, calculated from plastid gene sequences, was estimated to have occurred approximately 12 mya, coinciding with the divergence of the three genomes participating in the b event. Divergence of B. juncea A and B genome homoeologues was estimated to have taken place around 7 mya. Based on divergence time estimates and the presence of distinct plastid lineages in tribe Brassiceae, it is concluded that at least two independent triplication events involving reciprocal crosses at the time of the b event have given rise to Rapa/Oleracea and Nigra lineages. [ABSTRACT FROM AUTHOR]

To evaluate Ovo-transferrin (OTF), a positive acute-phase protein in chickens, as a diagnostic biomarker of selected bacterial infections we checked the performance of a commercial Chicken-OTF-ELISA (ICL, Inc., Portland, OR, USA) by analytical and overlap performances using two groups of serum samples obtained from 26Gallibacterium anatis-infected and 20Streptococcus zooepidemicus-infected brown layer chickens. In addition, sera from 14 apparently healthy and 19 negative control chickens were analysed in theGallibacteriumgroup whereas sera from 20 healthy and 11 negative control chickens from theStreptococcusgroup were analysed. All calibration curves revealed high coefficients of determination (≥0.97) between optical density (OD450nm) and concentrations of OTF (mg/ml). OTF concentrations in high, medium and low pools (made of sera from a combination of infected and/or non-infected birds) were >6.4, >3.8 to <4.5 and <1.6 mg/ml in theGallibacteriumgroup, and >6.7, >3.5 to <3.7 and <1.1 mg/ml in theStreptococcusgroup, respectively. For each pool, low coefficients of intra-assay (7.8, 5.7 and 5.3) and inter-assay (15.8, 18.0 and 18.0) variations were obtained in theGallibacteriumstudy. In theStreptococcusstudy only the intra-assay variation was low (3.7, 3.8 and 6.2, respectively). The linearity check was acceptable demonstrating a straight line with slope and intercept, not deviating from one and zero, respectively, using theGallibacteriumsera, whereas theStreptococcussera deviated from the linear line. Detection limits were low (Gallibacterium, 0.01 mg/ml;Streptococcus, 0.32 mg/ml). OTF concentrations (mean ± standard error of the mean) in overlap performances were elevated in the sera of infected chickens (Gallibacterium, 4.4 ± 0.3 mg/ml;Streptococcus, 3.2 ± 0.4 mg/ml) compared with negative controls (1.7 ± 0.1 mg/ml) (P< 0.05). In conclusion, the Chicken-OTF-ELISA can be used to measure reproducible serum OTF concentrations in brown layer chickens as a response toG. anatisinfections, whereas an adjustment of dilution process is proposed to optimize to use inS. zooepidemicus-infected chickens. [ABSTRACT FROM AUTHOR]