Demographic and Clinical Characteristics of Functional Dyspepsia and Its Subtypes in Adult Patients: An Experience from a Tertiary Care Centre in Bangladesh

Functional dyspepsia (FD) is a common gastrointestinal problem in the world. The Rome III consensus subdivided functional dyspepsia into two groups: meal-related postprandial distress syndrome (PDS) and meal-unrelated epigastric pain syndrome (EPS). Limited data are available regarding FD in Bangladesh. The aim of this study was to investigate the demographic and clinical characteristics of FD and its sub-types. This cross-sectional study was conducted in which we recruited patients who attended the outpatient department of Gastroenterology of Bangabandhu Sheikh Mujib Medical University, Bangladesh from March 2017 to February 2018. Patients fulfilling Rome III FD criteria and a negative upper GIT endoscopy were included for this study. The patients were then subdivided into 'pure' PDS (i.e. meeting criteria for PDS without EPS symptoms), 'pure' EPS (i.e., meeting criteria for EPS without PDS symptoms), and overlapping PDS-EPS (i.e., symptoms of both PDS and EPS) groups. Total of 368 FD patients (56.0% females, mean age 32.8±8.6 years, BMI: 22.0±2.7), were included in this study. Out of them, 112(30.4%) patients (57.2% females, mean age 33.9±9.3 years, BMI: 22.0±2.7) fulfilled criteria of pure EPS and 64(17.4%) patients (68.8% females, mean age 33.2±7.8 years, BMI: 22.1±2.4) fulfilled criteria of pure PDS. However, the majority of patients [192(52.2%), 52.1% females, mean age 32.0±8.4 years, BMI: 21.9±2.8] had symptoms of overlapping EPS-PDS. More than 40% of patients in our study presented with 3 or more of the four key symptoms of FD. A longer duration of presenting symptoms was seen among patients with overlapping EPS-PDS in comparison to pure EPS and pure PDS (p<0.001). A significant overlap of symptoms of both EPS and PDS was noticed among patients with FD. The value of dividing functional dyspepsia into the subgroups of PDS and EPS is thus questionable. Further research and modification of the diagnostic criteria for FD subtypes are necessary.

Inactivation of Human Norovirus GII.4's Infectivity in Fresh Oysters (Crassostrea gigas) through Thermal Treatment in Association with Propidium Monoazide

The current study investigated the effects of heat treatment (85 °C or 100 °C for 5-20 min) on human norovirus (HuNoV) GII.4's capsid stability in fresh oysters. In addition, propidium monoazide (PMA) was used in viral samples to distinguish infectious viruses and evaluated using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR). Further, we explored the effect of the heat treatment on oyster quality (Hunter color and hardness). The titer of HuNoV for oysters significantly (p < 0.05) decreased to 0.39-1.32 and 0.93-2.27 log10 copy number/μL in the non-PMA and PMA-treated groups, respectively, after heat treatment. HuNoV in oysters not treated with PMA showed a decrease of <1.5 - log10, whereas in PMA-treated oysters, a decrease of >1 - log10 was observed after treatment at 85 °C for 10 min. Treatments for both 15 min and 20 min at 100 °C showed a >99% log10 reduction using PMA/RT-qPCR. In the Hunter color, an increase in heat temperature and duration was associated with a significant decrease in 'L' (brightness+, darkness-) and an increase in 'a' (redness+, greenness-) and 'b' (yellowness+, blueness-) (p < 0.05). Our findings confirmed that the hardness of oyster meat significantly increased with increasing temperature and time (p < 0.05). This study demonstrated that PMA/RT-qPCR was effective in distinguishing HuNoV viability in heat-treated oysters. The optimal heat treatment for oysters was 10 min at 85 °C and 5 min at 100 °C.

Application of High-Pressure Processing (or High Hydrostatic Pressure) for the Inactivation of Human Norovirus in Korean Traditionally Preserved Raw Crab

Human norovirus (HuNoV) is a common cause of outbreaks linked to food. In this study, the effectiveness of a non-thermal method known as high-pressure processing (HPP) on the viable reduction of an HuNoV GII.4 strain on raw crabs was evaluated at three different pressures (200, 400, and 600 MPa). HuNoV viability in raw crabs was investigated by using propidium monoazide/sarkosyl (PMA) as a nucleic acid intercalating dye prior to performing a real-time reverse transcription-polymerase chain reaction (RT-qPCR). The effect of the HPP exposure on pH, sensory, and Hunter colors were also assessed. HuNoV was reduced in raw crabs compared with control to HPP (0.15-1.91 log) in non-PMA and (0.67-2.23 log) in PMA. HuNoV genomic titer reduction was <2 log copy number/µL) when HPP was treated for 5 min without PMA pretreatment, but it was reduced to >2 log copy number/µL after PMA. The pH and Hunter colors of the untreated and HPP-treated raw crabs were significantly different (p < 0.05), but sensory attributes were not significant. The findings indicate that PMA/RT-qPCR could be used to detect HuNoV infectivity without altering the quality of raw crabs after a 5 min treatment with HPP. Therefore, HuNoV GII.4 could be reduced up to 2.23 log in food at a commercially acceptable pressure duration of 600 MPa for 5 min.

Inhibition of Listeria monocytogenes Cocktail Culture Biofilms on Crab and Shrimp Coupons and the Expression of Biofilm-Related Genes

Listeria monocytogenes, a bacterium that is transmitted by tainted food, causes the infection listeriosis. In this study, quercetin was tested for its antibacterial properties and effectiveness as a food additive in preventing the growth of L. monocytogenes cocktail (ATCC19117, ATCC19113, and ATCC15313) biofilms on crabs and shrimps. Quercetin showed the least bactericidal activity and no discernible microbial growth at a minimum inhibitory concentration (MIC) of 250 µg/mL. The biofilm inhibition was performed at sub-MICs (1/2, 1/4, and 1/8 MIC). There was no quercetin added to the control group. Additionally, the present work examines the expression of various genes related to biofilm formation and quorum sensing (flaA, fbp, agrA, hlyA, and prfA). The levels of target genes were all significantly down-regulated. Quercetin (0-125 µg/mL) on the surfaces of the crab and shrimp was studied; its inhibitory effects were measured as log reductions at 0.39-2.31 log CFU/cm² and 0.42-2.36 log CFU/cm², respectively (p < 0.05). Quercetin reduced the formation of biofilms by disrupting cell-to-cell connections and causing cell lysis, which led to the deformation of the cells, evidenced by FE-SEM (field-emission scanning electron microscopy). These findings emphasize the significance of using natural food agents to target bacteria throughout the entire food production process.

Inhibitory effects of vorinostat (SAHA) against food-borne pathogen Salmonella enterica serotype Kentucky mixed culture biofilm with virulence and quorum-sensing relative expression

Salmonella is a food-borne microorganism that is also a zoonotic bacterial hazard in the food sector. This study determined how well a mixed culture of Salmonella Kentucky formed biofilms on plastic (PLA), silicon rubber (SR), rubber gloves (RG), chicken skin and eggshell surfaces. In vitro interactions between the histone deacetylase inhibitor-vorinostat (SAHA)-and S. enterica serotype Kentucky were examined utilizing biofilms. The minimum inhibitory concentration (MIC) of SAHA was 120 µg mL-1. The addition of sub-MIC (60 µg mL-1) of SAHA decreased biofilm formation for 24 h on PLA, SR, RG, Chicken skin, and eggshell by 3.98, 3.84, 4.11, 2.86 and 3.01 log (p < 0.05), respectively. In addition, the initial rate of bacterial biofilm formation was higher on chicken skin than on other surfaces, but the inhibitory effect was reduced. Consistent with this conclusion, virulence genes expression (avrA, rpoS and hilA) and quorum-sensing (QS) gene (luxS) was considerably downregulated at sub-MIC of SAHA. SAHA has potential as an anti-biofilm agent against S. enterica serotype Kentucky biofilm, mostly by inhibiting virulence and quorum-sensing gene expression, proving the histone deacetylase inhibitor could be used to control food-borne biofilms in the food industry.

A facile and green synthesis of Mn and P functionalized graphitic carbon nitride nanosheets for spintronics devices and enhanced photocatalytic performance under visible-light

Manganese and phosphorus co-doped, graphitic carbon nitride (g-C₃N₄) nanosheet (Mn/P-g-C₃N₄) is prepared by facile and green calcination process of melamine (C₃H₆N₆), manganese chloride tetrahydrate (MnCl₂·4H₂O), and ammonium dihydrogen phosphate ((NH₄)H₂PO₄). The Mn/P co-doping significantly enhances magnetic values compared to pristine-g-C₃N₄, phosphorus-doped g-C₃N₄ (P-g-C₃N₄), and manganese-doped g-C₃N₄ (Mn-g-C₃N₄). We find that Mn/P-g-C₃N₄ is a half-metallic ferromagnetic material having a magnetic moment and Curie temperature of 4.51 μ_B and ∼ 800 K, respectively. The ultraviolet-visible (UV-vis) absorption spectrum of Mn/P-g-C₃N₄ reveals superior absorption in broader wavelength compared to pristine-g-C₃N₄, P-g-C₃N₄, and Mn-g-C₃N₄. The methyl orange degradation efficiency of Mn/P-g-C₃N₄ photocatalyst is 94 %, which is three times more than that of pristine-g-C₃N₄ (29 %) and more significant than the P-g-C₃N₄ (46 %) and Mn-g-C₃N₄ (58 %). Furthermore, density functional theory (DFT) calculation explains the origin of high magnetic behavior, the boosted photocatalytic efficiency of Mn/P-g-C₃N₄, and the essential material properties like structure, bandgap, the density of states (DOS), and atomic level interaction. This work may be helpful for reasonably designing ferromagnetic material for spintronics devices and boosting visible-light (VL) photocatalytic performance for environmental remediation.

Effect of Dielectric Barrier Discharge Plasma against Listeria monocytogenes Mixed-Culture Biofilms on Food-Contact Surfaces

Listeria monocytogenes is a major foodborne pathogen. Various methods can be used to control biofilms formed by foodborne pathogens. Recently, the food industry has become interested in plasma, which can be used as a non-thermal technology with minimum changes to product quality. In this study, the effects of dielectric barrier discharge (DBD) plasma on L. monocytogenes mixed-culture biofilms formed on stainless steel (SS), latex hand glove (HG), and silicone rubber (SR) were investigated. DBD plasma effectuated reductions of 0.11-1.14, 0.28-1.27 and 0.37-1.55 log CFU/cm², respectively. Field emission scanning electron microscopy (FE-SEM) demonstrated that DBD plasma cuts off intercellular contact and induces cell decomposition to prevent the development of biological membranes. It was confirmed that the formed biofilms collapsed and separated into individual bacteria. Our findings suggest that DBD plasma can be used as an alternative non-heating sterilization technology in the food industry to reduce biofilm formation on bacterial targets.

Role of antioxidants in fertility preservation of sperm - A narrative review

Male fertility is affected by multiple endogenous stressors, including reactive oxygen species (ROS), which greatly deteriorate the fertility. However, physiological levels of ROS are required by sperm for the proper accomplishment of different cellular functions including proliferation, maturation, capacitation, acrosomal reaction, and fertilization. Excessive ROS production creates an imbalance between ROS production and neutralization resulting in oxidative stress (OS). OS causes male infertility by impairing sperm functions including reduced motility, deoxyribonucleic acid damage, morphological defects, and enhanced apoptosis. Several in-vivo and in-vitro studies have reported improvement in quality-related parameters of sperm following the use of different natural and synthetic antioxidants. In this review, we focus on the causes of OS, ROS production sources, mechanisms responsible for sperm damage, and the role of antioxidants in preserving sperm fertility.

Pernicious Attitude of Microbial Biofilms in Agri-Farm Industries: Acquisitions and Challenges of Existing Antibiofilm Approaches

Biofilm is a complex matrix made up of extracellular polysaccharides, DNA, and proteins that protect bacteria against physical, chemical, and biological stresses and allow them to survive in harsh environments. Safe and healthy foods are mandatory for saving lives. However, foods can be contaminated by pathogenic microorganisms at any stage from farm to fork. The contaminated foods allow pathogenic microorganisms to form biofilms and convert the foods into stigmatized poison for consumers. Biofilm formation by pathogenic microorganisms in agri-farm industries is still poorly understood and intricate to control. In biofilms, pathogenic bacteria are dwelling in a complex manner and share their genetic and physicochemical properties making them resistant to common antimicrobial agents. Therefore, finding the appropriate antibiofilm approaches is necessary to inhibit and eradicate the mature biofilms from foods and food processing surfaces. Advanced studies have already established several emerging antibiofilm approaches including plant- and microbe-derived biological agents, and they proved their efficacy against a broad-spectrum of foodborne pathogens. This review investigates the pathogenic biofilm-associated problems in agri-farm industries, potential remedies, and finding the solution to overcome the current challenges of antibiofilm approaches.

Effects of dietary intake behavior, food supply, nutrition, and health during the COVID-19 outbreak

The coronavirus disease 2019 (COVID-19) pandemic, which began in 2019, has far-reaching ramifications, including economic losses and health challenges that still affect various parts of the world. During our review, we learned that the entire world is working to stop the spread of the SARS-CoV-2 outbreak. We explore ways that may lower the danger of SARS-CoV-2 contamination and useful strategies to avoid the possibility of SARS-CoV-2 spreading through food. While hygienic protocols are required in the food supply sector, cleaning, disinfection, and the avoidance of cross-contamination across food categories and other related goods at different stages of the manufacturing process remain especially important because the virus can survive for long periods of time on inert materials such as food packaging. Furthermore, personal hygiene (regular washing and disinfection), wearing gloves and using masks, garments, and footwear dedicated to maintaining hygiene provide on-site safety for food sector personnel, supply chain intermediaries, and consumers. Restrictions imposed in response to the pandemic (e.g., closure of physical workplaces, canteens, cafes, restaurants, schools, and childcare institutions), changes in household grocery shopping frequency, individuals' perceived risk of COVID-19, income losses due to the pandemic, and sociodemographic factors are among the factors. The conclusions drawn from this study consider the implications of healthy diets, food system resilience, behavior change, and nutritional imbalance for policymakers and food supply chain participants, as well as the antimicrobial effects of vitamins and nutrients. During a public health crisis, people should eat less, necessitating preventive policies and nutritional advice to deal with this.

The Inhibitory Effect of Quercetin on Biofilm Formation of Listeria monocytogenes Mixed Culture and Repression of Virulence

Listeria monocytogenes is the species of foodborne pathogenic bacteria that causes the infection listeriosis. The food production chain employs various methods to control biofilms, although none are completely successful. This study evaluates the effectiveness of quercetin as a food additive in reducing L. monocytogenes mixed cultures (ATCC19113, ATCC19117, and ATCC15313) biofilm formation on stainless steel (SS), silicon rubber (SR), and hand glove (HG) coupons, as well as tests its antimicrobial activities. With a minimum inhibitory concentration (MIC) of 250 µg/mL, the tested quercetin exhibited the lowest bactericidal action with no visible bacterial growth. In contrast, during various experiments in this work, the inhibitory efficacy of quercetin at sub-MICs levels (1/2, 1/4, and 1/8 MIC) against L. monocytogenes was examined. A control group was not added with quercetin. The current study also investigates the effect of quercetin on the expression of different genes engaged in motility (flaA, fbp), QS (agrA), and virulence (hlyA, prfA). Through increasing quercetin concentration, swarming and swimming motility, biofilm formation, and expression levels of target genes linked to flagella motility, virulence, and quorum-sensing were all dramatically reduced. Quercetin (0−125 μg/mL) was investigated on the SS, SR, and HG surfaces; the inhibitory effects were 0.39−2.07, 0.09−1.96 and 0.03−1.69 log CFU/cm2, respectively (p < 0.05). Field-emission scanning electron microscopy (FE-SEM) corroborated the findings because quercetin prevented the development of biofilms by severing cell-to-cell contacts and inducing cell lysis, which resulted in the loss of normal cell shape. Our findings suggest that plant-derived quercetin should be used as an antimicrobial agent in the food industry to control the development of L. monocytogenes biofilms. These outcomes suggest that bacterial targets are of interest for biofilm reduction, with alternative natural food agents in the food sector along the entire food production chain.

Molecular and pathogenic characterization of Vibrio parahaemolyticus isolated from seafood

Gastroenteritis infections in humans are mainly associated with consumption of Vibrio parahaemolyticus contaminated shellfish, which causes health and economic loss. Virulence factor production, antibiotic resistance profile, and biofilm-forming capacity of Vibrio parahaemolyticus isolates on food and food contact surfaces at 30 °C were investigated to evaluate the antibiotic sensitivity and pathogenic level. Strains of V. parahaemolyticus were isolated from shellfish (e.g., Crassostrea gigas, Venerupis philippinarum, Mytilus coruscus, Anadara kagoshimensis) in Korea. When examined for 17 virulence factor-encoding genes, 53.3, 73.1, 87.1, 87.9, and 90.9% of the isolates were positive for genes encoding TDH, T6SS, T3SS1, T3SS2, and Type I pilus, respectively. All isolates showed resistance to vancomycin, tetracyclines, penicillin, nalidixic acid, and doxycycline, among 26 antibiotics tested, with most isolates resistant to kanamycin (93.5%), ampicillin (96.8%), clindamycin (96.8%), tobramycin (88.7%), amikacin (83.97%), and minocycline (80.7%). Biofilm formation, cell-cell attachment, and motility were high in most isolates. These findings may assist in monitoring the epidemics of the pathogen. Continuous monitoring could help to decrease V. parahaemolyticus infections and improve seafood safety.

Listeria monocytogenes biofilm inhibition on food contact surfaces by application of postbiotics from Lactobacillus curvatus B.67 and Lactobacillus plantarum M.2

Owing to their preservative and antimicrobial effects, postbiotics (metabolic byproducts of probiotics) are promising natural components for the food industry. Therefore, the present study aimed to investigate the efficacy of postbiotics collected from isolated Lactobacillus curvatus B.67 and Lactobacillus plantarum M.2 against Listeria monocytogenes pathogens in planktonic cells, motility, and biofilm states. The analysis of the metabolite composition of the postbiotics revealed various organic acids, along with a few well-known bacteriocin-encoding genes with potential antimicrobial effects. Postbiotics maintained their residual antimicrobial activity over the pH range 1-6 but lost all activity at neutral pH (pH 7). Full antimicrobial activity (100%) was observed during heat treatment, even under the autoclaving condition.Minimum inhibitory concentration (MICs) of L. curvatus B.67 and L. plantarum M.2 against L. monocytogenes were 80 and 70 mg/mL, respectively. However, four sub-MICs of the postbiotics (1/2, 1/4, 1/8, and 1/16 MIC) were tested for inhibition efficacy against L. monocytogenes during different experiment in this study. Swimming motility, biofilm formation, and expression levels of target genes related to biofilm formation, virulence, and quorum-sensing were significantly inhibited with increasing postbiotics concentration. Postbiotics from L. plantarum M.2 exhibited a higher inhibitory effect than the postbiotics from L. curvatus B.67. Nonetheless, both these postbiotics from Lactobacillus spp. could be used as effective bio-interventions for controlling L. monocytogenes biofilm in the food industry.

Inhibitory effects of Flavourzyme on biofilm formation, quorum sensing, and virulence genes of foodborne pathogens Salmonella Typhimurium and Escherichia coli

Salmonella enterica and Shiga toxin-producing (or verotoxin-producing) Escherichia coli are major foodborne pathogens, posing substantial food safety risks. Due to the negative effects of chemical treatment against foodborne pathogens, the application of enzyme-based techniques is currently receiving great attention. Here, we evaluated the inhibitory properties of Flavourzyme, a commercial peptidase, against these two foodborne pathogens. We noticed 4.0 and 5.5 log inhibition of biofilm formation by S. Typhimurium and E. coli, respectively, while treated with sub-minimum inhibitory concentrations of Flavourzyme for 24 h. For both bacteria, the enzyme exhibited quorum-quenching activity, preventing autoinducer-2 production completely by E. coli. In addition, Flavourzyme significantly suppressed the relative expression levels of biofilm-forming, quorum sensing, and virulence regulatory genes as measured by qRT-PCR. Based on our results, we suggest the use of Flavourzyme as a preventive agent against foodborne pathogens that possibly acts by inhibiting bacterial self-defense mechanisms following disruption of cellular proteins. This finding may shed light on how enzymes can be applied as a novel weapon to control foodborne illnesses to ensure food safety and public health.

Effects of environmental conditions (temperature, pH, and glucose) on biofilm formation of Salmonella enterica serotype Kentucky and virulence gene expression

Salmonella is a foodborne pathogen and an emerging zoonotic bacterial threat in the food industry. The aim of this study was to evaluate the biofilm formation by a cocktail culture of 3 wild isolates of Salmonella enterica serotype Kentucky on plastic (PLA), silicon rubber (SR), and chicken skin surfaces under various temperatures (4, 10, 25, 37, and 42°C) and pH values (4.0, 5.0, 6.0, 7.0, and 8.0). Then, at the optimum temperature and pH, the effects of supplementation with glucose (0, 0.025, 0.05, and 0.4% w/v) on biofilm formation were assessed on each of the surfaces. The results indicated that higher temperatures (25 to 42°C) and pH values (7.0 and 8.0) led to more robust biofilm formation than lower temperatures (4 and 10°C) and lower pH levels (4.0 to 6.0). Moreover, biofilm formation was induced by 0.025% glucose during incubation at the optimum temperature (37°C) and pH (7.0) but inhibited by 0.4% glucose. Consistent with this finding, virulence related gene (rpoS, rpoH, hilA, and avrA) expression was increased at 0.025% glucose and significantly reduced at 0.4% glucose. This results also confirmed by field emission scanning electron microscope, confocal laser scanning microscopy, and autoinducer-2 determination. This study concluded that optimum environmental conditions (temperature 37°C, pH 7.0, and 0.25% glucose) exhibited strong biofilm formation on food and food contract surfaces as well as increased the virulence gene expression levels, indicating that these environmental conditions might be threating conditions for food safety.

Enhancing Oocyte Competence With Milrinone as a Phosphodiesterase 3A Inhibitor to Improve the Development of Porcine Cloned Embryos

The objective of this study was to investigate the effect of milrinone supplementation as a phosphodiesterase 3A inhibitor during in vitro maturation (IVM) to coordinate the cytoplasmic and nuclear maturation of porcine oocytes and subsequent development of porcine cloned embryos. Brilliant cresyl blue (BCB)-stained (BCB +) oocytes, classified as well-developed, and BCB− oocytes were used in parthenogenesis (PA) and cloning, and their preimplantation development was compared. In PA embryos, BCB + oocytes had significantly higher rates of development than BCB− oocytes in terms of maturation (87.5 vs. 71.3%), cleavage (88.6 vs. 76.3%), and blastocyst development (34.3 vs. 25.3%) and also had higher cell numbers (46.9 vs. 38.9%), respectively (p < 0.05). In cloned embryos, the BCB + group also had a significantly higher blastocyst formation rate than the BCB− group (30.6 vs. 20.1%; p < 0.05). Supplementation with 75 μM milrinone during IVM of BCB− oocytes showed improvement in maturation and blastocyst development rates, which may be due to the coordinated maturation of the cytoplasm with the nucleus as an effect of milrinone. Moreover, the analysis of nuclear reprogramming via the examination of the expression levels of the reprogramming-related genes POU5F1, DPPA2, and NDP52IL in milrinone-supplemented BCB− oocytes showed higher expression levels than that in non-treated BCB− oocytes. These findings demonstrate that milrinone is useful in improving developmental competence in less competent oocytes during IVM and for proper nuclear reprogramming in the production of porcine cloned embryos by coordinating cytoplasmic and nucleus maturation.

Comprehensive molecular, probiotic, and quorum-sensing characterization of anti-listerial lactic acid bacteria, and application as bioprotective in a food (milk) model

Listeria monocytogenes is a major foodborne pathogen that adversely affects the food industry. In this study, 6 anti-listerial lactic acid bacteria (LAB) isolates were screened. These anti-listerial LAB isolates were identified via 16S rRNA gene sequencing and analyzed via repetitive extragenic palindromic-PCR. Probiotic assessment of these isolates, comprising an evaluation of the antibiotic susceptibility, tolerance to lysozyme, simulated gastric and intestinal juices, and gut conditions (low pH, bile salts, and 0.4% phenol), was carried out. Most of the isolates were resistant to streptomycin, vancomycin, gentamycin, kanamycin, and ciprofloxacin. All of the isolates were negative for virulence genes, including agg, ccf, cylA, cylB, cylLL, cylLS, cylM, esp, and gelE, and hemolytic activity. Furthermore, autoinducer-2 (a quorum-sensing molecule) was detected and quantified via HPLC with fluorescence detection after derivatization with 2,3-diaminonaphthalene. Metabolites profiles of the Lactobacillus sakei D.7 and Lactobacillus plantarum I.60 were observed and presented various organic acids linked with antibacterial activity. Moreover, freeze-dried cell-free supernatants from Lb. sakei (55 mg/mL) and Lb. plantarum (40 mg/mL) showed different minimum effective concentration (MEC) against L. monocytogenes in the food model (whole milk). In summary, these anti-listerial LAB isolates do not pose a risk to consumer health, are eco-friendly, and may be promising candidates for future use as bioprotective cultures and new probiotics to control contamination by L. monocytogenes in the food and dairy industries.

Exfoliated two-dimensional molybdenum disulfide reinforced epoxy syntactic foams

In this paper, we report the effect of introducing molybdenum disulfide (MoS2) nano-platelets: a two-dimensional metal chalcogenide, on the mechanical properties of hollow glass microballoon (HGM)–epoxy syntactic foams. MoS2 reinforced syntactic foams were prepared by mixing MoS2 nanoplatelets to epoxy containing HGMs; with the amount of MoS2 being varied from 0.01 to 0.04% v/v, while maintaining a constant total filler volume fraction of 40% for all compositions. The mechanical behaviour of reinforced syntactic foam was studied under varied loadings including compressive, tensile and flexural under different strain rate regimes. Introduction of MoS2 led to significant improvements in characteristic mechanical properties, particularly in terms of compressive strength and toughness, which suggest intercalation of MoS2 within the epoxy matrix; however, the presence of relatively larger MoS2 micro particles couldn’t be completely negated. The toughness of the foam, as indicated by the area under the compressive stress-strain curve, was found to increase by ∼21% under optimal conditions. Our results highlight the potential of the two-dimensional MoS2 sheets as a reinforcing agent in syntactic foams.

COVID-19 pandemic crisis and food safety: Implications and inactivation strategies

Background

The COVID-19 pandemic that emerged in 2019 has imposed huge consequences, including economic losses and threats to human health, which are still affecting many aspects throughout the world.

Scope and approach

This review provides an overview of SARS-CoV-2 infection, the cause of COVID-19, and explores its impact on the food supply system and food safety. This review examines the potential risk of transmission through food and environmental surfaces before discussing an effective inactivation strategy to control the COVID-19 pandemic in the aspect of food safety. This article also suggests effective food safety management post-COVID-19.

Key findings and conclusions

Respiratory viruses including SARS-CoV-2 are responsible for huge impacts on the global economy and human health. Although food and water are not currently considered priority transmission routes of SARS-CoV-2, infection through contaminated food and environmental surfaces where the virus can persist for several days cannot be ignored, particularly when the surrounding environment is unhygienic. This approach could help determine the exact transmission route of SARS-CoV-2 and prepare for the post-COVID-19 era in the food safety sector.

Chitosan nanoparticles enhance developmental competence of in vitro-matured porcine oocytes

Oxidative stress is inevitable as it is derived from the handling, culturing, inherent metabolic activities and medium supplementation of embryos. This study was performed to investigate the protective effect of chitosan nanoparticles (CNPs) on oxidative damage in porcine oocytes. For this purpose, cumulus-oocyte complexes (COCs) derived from porcine slaughterhouse ovaries were exposed to different concentrations of CNPs (0, 10, 25 and 50 µg/ml) during in vitro maturation (IVM). Oocytes treated with 25 µg/ml CNPs showed significantly higher levels of GSH, along with a significant reduction in ROS levels compared to control, CNPs10 and CNPs50 groups. In parthenogenetic embryo production, the maturation rate was significantly higher in the CNPs25 group than that in the control and all other treated groups. In addition, when compared to the CNPs50 and control groups, CNPs25-treated oocytes showed significantly higher cleavage and blastocyst development rates. The highest concentration of CNPs reduced the total cell number and ratio of ICM: TE cells in parthenogenetic embryos, suggesting that there is a threshold where benefits are lost if exceeded. In cloned embryos, the CNPs25 group, as compared to all other treated groups, showed significantly higher maturation and cleavage rates. Furthermore, the blastocyst development rate in the CNPs25-treated group was significantly higher than that in the CNPs50-treated group, as was the total cell number. Moreover, we found that cloned embryos derived from the CNPs25-treated group showed significantly higher expression levels of Pou5f1, Dppa2, and Ndp52il genes, compared with those of the control and other treated groups. Our results demonstrated that 25 µg/ml CNPs treatment during IVM improves the developmental competence of porcine oocytes by reducing oxidative stress.

Study of thyroid function in pregnancy, its feto-maternal outcome; a prospective observational study

Background

Pregnancy is a stress test of maternal thyroid function. The prevalence of thyroid dysfunction in pregnant women is high. Subclinical hypothyroidism occurs in 10% of all pregnancies. Effects of hypothyroidism in pregnancy are anemia, low birth weight and mental retardation in neonate. This study is aimed to evaluate maternal and fetal outcomes in pregnant women with deranged thyroid profile. The relevance of this study is to document the association of hypothyroidism and its adverse effects on mother and fetus.

Methods

This prospective observational study was carried out at R.D. Gardi Medical College, Ujjain, India. Subjects of this study were 198 antenatal women in third trimester with singleton pregnancy admitted in the obstetric ward, and informed consent was obtained. Women were chosen irrespective of age, parity, residence and socioeconomic status. Women with multiple pregnancy, a known case of thyroid disorder, or any pre-existing medical disorder were excluded. Routine hematological parameters and estimation of T3, T4 and TSH was conducted. Patients with deranged thyroid profile were subsequently assessed for maternal and fetal complications. History of infertility, family history of thyroid disease, menstrual pattern, recurrent abortion, hemoglobin level and fetal outcome were the main study variables. Data was analysed in SPSS software for statistical co-relation.

Results

Prevalence of thyroid disorder is 11%; with subclinical hypothyroidism, overt hypothyroidism and subclinical hyperthyroidism occurring in 5.6, 3.5 and 1.5% of subjects respectively. In women with subclinical and overt hypothyroidism, anemia was present in 26.3% being significantly associated with hypothyroidism (p = 0.008). With respect to fetal outcome, LBW 31.6% (p = 0.001), NICU admission 42.1%, (p = 0.000) and low APGAR Score (21.1%, p = 0.042) were statistically associated with hypothyroidism. Risk of anemia, Low Birth weight, NICU admissions, and low APGAR score was 4.8, 6.3, 0.14 and 3.64 times higher respectively in women with hypothyroidism than in women who are euthyroid.

Conclusion

Prevalence of subclinical hypothyroidism is 5.6% in 3rd trimester of pregnancy. Anemia, pre-eclampsia, high caesarean rates and neonatal morbidities is significantly associated with hypothyroidism.

GW190521: A Binary Black Hole Merger with a Total Mass of 150 M_{⊙}

On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a short duration gravitational-wave signal, GW190521, with a three-detector network signal-to-noise ratio of 14.7, and an estimated false-alarm rate of 1 in 4900 yr using a search sensitive to generic transients. If GW190521 is from a quasicircular binary inspiral, then the detected signal is consistent with the merger of two black holes with masses of 85_{-14}^{+21}  M_{⊙} and 66_{-18}^{+17}  M_{⊙} (90% credible intervals). We infer that the primary black hole mass lies within the gap produced by (pulsational) pair-instability supernova processes, with only a 0.32% probability of being below 65  M_{⊙}. We calculate the mass of the remnant to be 142_{-16}^{+28}  M_{⊙}, which can be considered an intermediate mass black hole (IMBH). The luminosity distance of the source is 5.3_{-2.6}^{+2.4}  Gpc, corresponding to a redshift of 0.82_{-0.34}^{+0.28}. The inferred rate of mergers similar to GW190521 is 0.13_{-0.11}^{+0.30}  Gpc^{-3} yr^{-1}.

Viability of Salmonella Typhimurium biofilms on major food-contact surfaces and eggshell treated during 35 days with and without water storage at room temperature

Salmonella is one of the main foodborne pathogens that affect humans and farm animals. The Salmonella genus comprises a group of food-transmitted pathogens that cause highly prevalent foodborne diseases throughout the world. The aim of this study was to appraise the viability of Salmonella Typhimurium biofilm under water treatment at room temperature on different surfaces, specifically stainless steel (SS), plastic (PLA), rubber (RB), and eggshell (ES). After 35 D, the reduction of biofilm on SS, PLA, RB, and ES was 3.35, 3.57, 3.22, and 2.55 log CFU/coupon without water treatment and 4.31, 4.49, 3.50, and 1.49 log CFU/coupon with water treatment, respectively. The d_R value (time required to reduce bacterial biofilm by 99% via Weibull modeling) of S. Typhimurium without and with water treatment was the lowest on PLA (176.86 and 112.17 h, respectively) and the highest on ES (485.37 and 2,436.52 h, respectively). The viability of the S. Typhimurium on ES and the 3 food-contact surfaces was monitored for 5 wk (35 D). The results of this study provide valuable information for the control of S. Typhimurium on different surfaces in the food industry, which could reduce the risk to consumers.

Improved preimplantation development of porcine somatic cell nuclear transfer embryos by caffeine treatment

This study examined the effects of a caffeine treatment to improve nuclear reprogramming in porcine cloned embryos. Embryonic development and the expression of genes related to pluripotency (POU5F1, SOX2, NANOG, and CDX2) were compared after caffeine supplementation during manipulation at different concentrations (0, 1.25, 2.5, and 5.0 mM) and after varying the delayed activation time (control, 1, 2, and 4 h) after fusion. Caffeine added to media during manipulation produced a higher rate of development to blastocysts in the 1.25 mM group than in the other concentration groups (22.8% vs. 16.1%, 16.2%, and 19.2%; p < 0.05). When caffeine was added during the 4 h delayed activation, the 1.25 mM caffeine concentration produced a significantly higher rate of development than those in the other 4 h-activation-delayed caffeine concentration groups (22.4% vs. 9.4%, 14.0%, and 11.1%; p < 0.05). On the other hand, no significant improvement over that in the control group was observed when caffeine was supplemented during both the manipulation period and delayed activation period (16.0% vs. 15.2%), respectively. The levels of POU5F1, SOX2, and NANOG expression in blastocysts were significantly higher in the delayed activation caffeine group (4 h, 1.25 mM) than in the control group (1 h, 0 mM; p < 0.05). In conclusion, a caffeine treatment at 1.25 mM during delayed activation for 4 h can improve the preimplantation development of porcine somatic cell nuclear transfer embryos by activating nuclear reprogramming.

Evaluation of Duodenal Eosinophil Count in Adult Patients with Functional Dyspepsia

Several mechanisms have been proposed to explain the symptoms of functional dyspepsia but actual pathogenesis is still poorly understood. Recent studies support duodenal abnormality to be the most important causal link to explain symptoms and to understand abnormal pathophysiology of functional dyspepsia. The aim of this prospective observational study is to compare eosinophil count in duodenal mucosa between patients with functional dyspepsia and control subjects without dyspepsia and was done at the department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from December 2015 to December 2016. Total 42 patients of functional dyspepsia based on Bangla validated version of ROME III criteria and 42 controls who were referred for upper gastrointestinal endoscopy for reasons other than dyspepsia were included. Biopsy specimens were collected from the second part (D2) of the duodenum of all participants. Eosinophil count was quantitatively evaluated by hematoxylin and eosin staining and expressed in numbers per 5 HPF. Significantly increased duodenal eosinophil count was found in functional dyspepsia group than non dyspeptic patients (22.78±08.78 vs. 14.90±10.70, p=0.001). Higher duodenal eosinophil count was found in patients with postprandial distress syndrome. Increased duodenal eosinophil count was found in patient of functional dyspepsia. It requires further large scale multicenter studies to establish duodenal eosinophilia as a biomarker of functional dyspepsia.

Bimatoprost in Dermatology

Bimatoprost is a prostamide analogue used for treatment of glaucoma in ophthalmology. Surprisingly, the side effects such as increased pigmentation of eyelids and hypertrichosis in patients being treated with prostaglandin analogues for glaucoma have opened new areas of application in various dermatological disorders such as alopecia mainly affecting eyelashes, eyebrows, and vitiligo.

Dermoscopy of alopecia areata-a retrospective analysis

Background

Dermoscopy devices can overcome the refractive properties of stratum corneum by interface medium or cross polarization such that the lesion can be easily seen.

Aim

To examine the dermoscopic feature in alopecia areata and correlate the severity of disease with dermoscopic features.

Materials and methods

Retrospective analysis of 72 patients suffering from alopecia areata (AA), irrespective of age and sex, who visited the dermatology outpatient department of a tertiary care center in Eastern India was carried out. The most recently developed cases of AA were examined dermoscopically. Variables included yellow dots (YDs), black dots (BDs), broken hair (BH), short vellus hair (SVH), and exclamation mark hair (EMH) on the basis of available literature and expertise.

Results

Yellow dots was the most common finding seen in 57 cases (79.16%), black dots in 51 cases (70.8%). Short vellus hair was seen in 32 cases (44.44%), broken hair was seen in 31 cases (43.05%), and exclamation mark hair in 23 cases (31.9%). YDs per field of vision was considered as the most common finding with increased severity of AA.

Conclusion

YDS, in increased number per field of vision, is the most consistent finding seen in severe cases of AA, as they are in progressive AA and alopecia universalis. An increased number of SVH and terminal hairs were seen in patients who were being treated.

Peptic Ulcer Disease in Bangladesh: A Multi-centre Study

The incidence of peptic ulcer has steadily declined through out the world. This decreasing trend is also noticeable in this subcontinent. The point prevalence of peptic ulcer (PUD) in Bangladesh was around 15% in eighties. The aim of this study was to see the present prevalence of peptic ulcer at endoscopy and to identify changing trends in the occurrence of peptic ulcer in Bangladesh. This retrospective analysis of the endoscopic records of multiple tertiary referral centres of Dhaka city were done from January 2012 to July 2013. A total of 5608 subjects were the study samples. We included those patients having peptic ulcer in the form of duodenal ulcer, benign gastric ulcer including pre-pyloric ulcer and gastric outlet obstruction due to peptic ulcer. Duodenal ulcer and benign gastric ulcer were found in 415(7.4%) and 184(3.28%) patients respectively and gastric outlet obstruction due to peptic ulcer was found in 23(0.40%) patients.

Pattern of Changes in the Findings among the Patients Undergoing Diagnostic Esophagogastroduodenoscopy in Bangladesh

This cross-sectional observational study was conducted in the Department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University, Sir Salimullah Medical College and Mitford Hospital, Holy family Red Crescent Medical College and Hospital and Popular Diagnostic Centre, Shantinagar branch, Dhaka, Bangladesh from January 2012 to July 2013. Study subjects were included in the study irrespective of age and sex having different upper GI tract. Complaints like dysphagia, heart burn, abdominal pain/dyspepsia, nausea, vomiting, haematemesis and/or malena, anorexia, unexplained anemia, weight loss etc. All the findings of oesophagus, stomach and duodenal lesions were observed and data were recorded. The results were considered positive based on the macroscopic appearance using standard diagnostic criteria. During the study period endoscopy was performed in 5608 subjects. Among which 2968(52.92%) were male and 2640(47.07%) were female. The patients age range from 7 years to 108 years. The majority of the patients were from 40-50 years. Normal findings were observed among 3321(59.21%) cases. Gastroduodenal erosions were present among 684(12.19%) cases, Oesophageal varices in 444(7.91%) cases, duodenal ulcer diseases in 415(7.40%) cases and gastric ulcer in 184(3.28%) cases. Ca stomach was found among 165(2.94%) cases. A number of diseases were identified through this procedure. Current study observed a large proportion of patients (40.79%) had positive upper GI endoscopy.

Genotypes of hepatitis C virus infection in Bangladeshi population

Hepatitis C virus (HCV) is a leading cause of chronic liver disease worldwide also in Bangladesh. Prevalence of Hepatitis C virus infection in rural adult population of Bangladesh is reported to be 0.6% but the exact pattern of existing genotype has not been well studied. Genotyping of HCV is important for the planning of treatment duration and predicting the response to treatment in HCV infection. This study was done to identify the existing HCV genotypes in the diagnosed cases of chronic hepatitis C infection in Bangladesh. This study was a prospective as well as retrospective cross-sectional observational study done in the department of Gastroenterology of Bangabandhu Sheikh Mujib Medical University, Dhaka Bangladesh. Cases were also taken from department of Hepatology of Bangabandhu Sheikh Mujib Medical University and Square General Hospital, Dhaka. The study was from January 2010 to March 2011. In total, 417 patients having chronic HCV confirmed by positive anti-HCV and HCV-RNA tests attending to above mentioned institutions were included in this study. Out of the 417 study subjects, 303 were males (72.66%) and 114 (27.34%) were females between 05 to 78 years of age. Most cases were in the age group 30-50 years (57.06%). The study showed that 209 (50.19%) were infected with Genotype 3. Next common identified genotype of HCV was a combination of type 3 & 4, which accounted for 120 (28.77%) and genotype -1 represented 59 (14.14%) of the cases. Other less common identified genotypes were 2, 4, 5 and mixed genotypes -1 & 3, 5 & 6 and 2 & 3; the figure being 12(2.87%), 8(1.91%), 1(0.23%), 5(1.19%), 2(0.47%) and 1(0.23%) respectively. Several subtypes were also found. Genotype 3 was the commonest HCV genotype among the Bangladeshi population. Different HCV genotypes will give a good idea regarding the plan of treatment and possible response rate as well as prognosis of HCV infection in Bangladesh. This study had some limitation like relatively smaller sample size and shorter period for the study. Further studies over a larger population are needed to draw any conclusive opinion.

Efficacy of adefovir dipivoxil therapy in patients with chronic hepatitis B viral infection

Hepatitis B virus (HBV) infection is a major public health problem in the world. About 30% of world population has serological evidence of HBV infection. The prevalence of chronic hepatitis B in Bangladesh is reported to be 7.8%. Several potentially effective agents with different mechanisms of action have entered clinical practice and adefovir dipivoxil is one of them. Studies on the efficacy of adefovir dipivoxil in Bangladeshi patients are lacking. This was a prospective study to find out the effect of one year adefovir therapy in patients with chronic hepatitis B virus infection who were HBeAg positive. Total number of patients included in this study was 68. Among them 53(77.94%) patients continued the therapy and completed follow up. At the end of one year of therapy, intention to treat analysis showed that the rate of response (HBeAg seroconversion and HBV DNA negative) was 37.73% which was comparable to the results obtained in other studies. There was major difference in the pre treatment serum ALT level between the responders and non-responders. Comparison of reduction of serum ALT level before treatment and after treatment showed that ALT level to be lower in both responder group and non responder group. Adefovir was effective in replicative HBV infection in Bangladeshi population. So we suggest that treatment can be started and subsequent follow up can be done in chronic HBV patients who are HBeAg positive without liver biopsy.

Prevalence of colorectal diseases in immunological fecal occult blood test (I-FOBT) positive patients in a tertiary care hospital in Bangladesh

Bleeding lesion anywhere in the GI tract can cause positive reaction to Immunological Fecal Occult Blood Test (FOBT). Although any colonic lesion can cause occult lower GI bleeding, relative frequency of this lesion not known. Guaic based tests require prior preparation and dietary restriction and less sensitive and specific than IFOBT for detection of occult bleeding .IFOBT is specific for human hemoglobin and is more sensitive and specific for detection of occult bleeding from any colonic lesion. Aim of this study was to diagnose occult gastrointestinal bleeding with positive IFOBT and the prevalence of colorectal disease in IFOBT positive patients in a tertiary care hospital in Bangladesh. This was a prospective cross sectional study conducted in Department of gastroenterology in collaboration with clinical pathology, BSMMU, Dhaka during the period of January 2009 to December 2009. In this study 200 patients meeting the inclusion criteria were included. Detailed clinical history and physical findings were recorded; FOBT was done on single stool specimen. Positive occult bleeding was confirmed in 90 patients of whom 80 patients underwent colonoscopy. The mean age of study population was 36.73±13.64 (range 16 to 72) years. At colonoscopy lesion were identified in 46(57.50%) patients, of which colonic polyp in12 (15%), colorectal cancer in 11(13.7%), inflammatory bowel disease in 3(3.75%), hemorrhoids and anal fissure in 7(8.75%), tuberculosis in 5(6.25%), and proctitis in 1(1.25%) cases. A positive IFOBT is more sensitive and specific test than other FOBT for detection of occult lower GI bleeding of colonic origin. In this study colorectal diseases were detected in 57.50% of the IFOBT positive patients, so IOBT can be used as an important diagnostic tool for detection of occult lower GI bleeding.

Disease extent and local complication of ulcerative colitis in Bangladeshi population

Ulcerative colitis may involve anywhere from the rectum alone to the entire colon. Local complications like perforation, life threatening haemorrhage, toxic megacolon, pseudo polyps, stricture, and carcinoma of colon are seen. Patients who were diagnosed as Ulcerative Colitis in Departmental Ulcerative Colitis record book from January 1990 to June 2010 was considered as study population. Information regarding the extent of the disease and local complications were taken from earliest documented Lower GIT Endoscopy. Out of 164 patients disease extent were seen in 126(76.83%) patients and among them proctitis/proctosigmoiditis were seen in 57(45.24%) patients, left sided colitis were seen in 11(8.73%) patients, extensive/pan colitis were seen in 58(46.03%) patients. Complication were seen in 164 patients and 1(0.60%) patient had life threatening haemorrhage, 25(15.24%) patients developed pseudo polyps. There was no report of perforation, toxic megacolon, stricture or carcinoma of colon. The differences found between our study and studies from other Western and Asian countries in terms of complication rate and disease extent for were probably due to low index of suspicion, incomplete workup, or incomplete records, and influence of various environmental factors. So, further large scale prospective evaluation is suggested.

Efficacy of Peppermint oil in diarrhea predominant IBS - a double blind randomized placebo - controlled study

Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorder which is associated with considerable sufferings of patient and Peppermint oil is volatile oil, its active principle is menthol-contain a cyclic monoterpine which has anti-spasmotic properties due to its ability to block calcium channel of intestinal smooth muscles. This study observed the efficacy of peppermint oil for relieving the symptoms and changes of quality of life (QOL) in diarrhea predominant IBS. This was a prospective double blind randomized placebo-controlled study conducted in the Bangabandhu Sheikh Mujib Medical University during July 2008 to September 2009. Patients who fulfilled ROME II were initially selected but those had red flag signs or any organic disease was excluded from the study. Seventy four patients were enrolled in the study and randomly allocated to receive either peppermint oil or placebo three times daily for six weeks. Changes of symptoms were assessed three week interval during treatment and two weeks after the end of treatment. Data were analyzed by paired and unpaired 't' test. Finally sixty five patients completed the trial. It was observed that, at six weeks of therapy abdominal pain is markedly improved (mean±SD) 4.94±1.30 in peppermint oil group compared with 6.15±1.24 in placebo group and the difference was statistically highly significant (p>0.001). But two weeks after end of trials pain score again increased (6.09±1.93). Other symptoms and quality of life did not improve significantly. So the study result concludes that peppermint oil is effective in reliving only abdominal pain in diarrhea predominant IBS transiently.

Clinicopathological profile of patients with abdominal tuberculosis

BACKGROUND

Tuberculosis (TB) is not a uncommon problem throughout the world particularly in the developing countries like Nepal, India and Bangladesh. Abdominal Tuberculosis accounts for nearly 2% of tuberculosis worldwide. The aim of this study was to evaluate the clinicopathological profile with the help of other investigations in the diagnosis of patients with abdominal TB and their response to anti-tubercular therapy. This was a prospective cross-sectional study conducted in the department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka during the period of October 2002 to June 2009.

METHODS

Total 53 patients with abdominal TB diagnosed on the basis of clinical profile and supported investigation data like gross morphological findings at endoscopy, colonoscopy, diagnostic laparoscopy , laparotomy or histologically proven caseating granulomas were selected for this study. Detailed demographic, clinical profile, investigations and treatment response were recorded properly in a predesigned data collection sheet which were analyzed and compared with other studies.

RESULTS

Out of the 53 patients, 33 were males and 20 females with age ranging 16-70 (Mean 30.01±11.7) years. Abdominal pain was the most common presenting symptom in 47 (88.68%), fever in 45 (84.9%) and weight loss in 37 (69.81%) cases. Anemia was found in 41 (77.36%), cachexia 40 (75.47%), ascites 20 (37.74%), palpable abdominal mass in 14 (26.42%) and features of intestinal obstruction in 5 (9.43%) cases. Five patients had positive family history of TB and five had past history of pulmonary TB. The diagnosis of abdominal TB was confirmed microscopically in 5 (9.43%), histopathologically in 31 (58.49%) and the remaining 17 (32.07%) cases were diagnosed by a positive response to anti-TB therapy. According to site of involvement, 31 (58.51%), patients had intestinal TB, 9 (16.98%) had peritoneal TB and disseminated TB in 20 (37.74%) of the case. Twenty seven patients were given 3 drugs regimen for 12 months and 26 patients received 4 drugs regimen for 9 months under close supervision. By 9 months of therapy 51 patients become symptom free and no pathological findings were observed thereafter at follow up visits after 6 months. Response was not satisfactory in two patients and subsequent follow up investigation revealed to have crohn's disease rather than TB and none of them died.

CONCLUSIONS

Abdominal TB is an important clinical entity having varied mode of clinical presentation. So the diagnosis of abdominal TB is difficult and careful approach to the patients and supportive investigation data are necessary to make the final diagnosis. Neither clinical features, laboratory, radiological and Endoscopic methods nor bacteriological and histopathological findings by themselves provide a gold standard in the diagnosis of abdominal TB. In this series of abdominal TB, intestinal TB was the most frequent clinical type and the common presenting symptoms were abdominal pain, fever and weight loss. If diagnosed early, it can be treated successfully with anti-TB drugs.

Cochlear Implant : Anaesthesia Challenges

BACKGROUND

Cochlear implants are now an acceptable therapeutic option for those patients with irreversible hearing loss and deaf-mutism. The surgery is time consuming and complicated. Hence, the technique of anaesthesia plays a crucial role in success of cochlear implant surgery. Cochlear implant patients have various types of syndromes which are important from anaesthetic as well as surgical point of view. Pre-implant preparation requires objective assessment of hearing, plain X-rays of skull and a CT scan of the temporal bone. Anaesthesia is required for objective assessment of hearing in children under five years of age, to obtain X-rays of skull, magnetic resonance imaging (MRI), CT scan, brain evoked response audiometry (BERA) testing and finally for cochlear implant surgery. Anaesthetic considerations include preoperative familiarisation with the patient and his family. Syndromal illnesses have specific anaesthetic significance such as presence of difficult airway or prolonged QT interval. Parental presence is highly desirable during induction of anaesthesia. Electro-surgical instruments especially monopolar ones, should not be used once the cochlear implant is in place.

METHODS

In our institution, all cases (15 children) received their cochlear implants under general anaesthesia and formed the study group. Children were administered midazolam orally and inj ketamine during CT scan. Our techniques of general anaesthesia were modified to permit use of nerve stimulators during surgery. To minimise the incidence of vertigo particularly after cochleostomy, postoperative nausea and vomiting, all patients received glycopyrrolate and fentanyl citrate intravenously prior to induction. Other agents used were, thiopentone, suxamethonium and end-tidal 1.3 MAC halothane in 1:2 mixture of oxygen and nitrous oxide (O2 and N2O). Electro diathermy was switched off, before the cochlear device was implanted on the patient. Patients were allowed to breathe spontaneously whenever nerve stimulator was used to locate the facial nerve. Inj Ondansetron 0.1 mg/kg was used as anti-emetic agent. Postoperative pain relief was initially provided with fentanyl 1 μg/kg IV and later with syrup ibuprofen.

RESULTS

There were no remarkable anaesthetic or surgical complication in our series except perilymph leakage in two cases.

Engineering generalized synchronization in chaotic oscillators

We report a method of engineering generalized synchronization (GS) in chaotic oscillators using an open-plus-closed-loop coupling strategy. The coupling is defined in terms of a transformation matrix that maps a chaotic driver onto a response oscillator where the elements of the matrix can be arbitrarily chosen, and thereby allows a precise control of the GS state. We elaborate the scheme with several examples of transformation matrices. The elements of the transformation matrix are chosen as constants, time varying function, state variables of the driver, and state variables of another chaotic oscillator. Numerical results of GS in mismatched Rössler oscillators as well as nonidentical oscillators such as Rössler and Chen oscillators are presented.

Li+ ion emission from a hot-plate alumina-silicate source stimulated by flash heating with an infrared laser

The Neutralized Drift Compression Experiment-II accelerator under construction at Lawrence Berkeley National Laboratory has been designed to employ a lithium-doped alumino-silicate (Al-Si) hot-plate surface-ionization ion source. In order to achieve the design 1 mA∕cm(2) current density, the emitter must be constantly kept at a high temperature, leading to the accelerated loss of Li material as ions or neutrals. As a result, the estimated lifetime of the source is 50 h. This lifetime can be extended if the source is kept at low temperature during standby, and pulse heated to the high temperature during the ion extraction phase only. A pulsed heating technique based on an infrared laser (CO(2) gas discharge, λ = 10.6 μm) is described in this paper. The feasibility of ion current emission stimulated by flash heating with an infrared (IR) laser was demonstrated. High repeatability of the laser-stimulated ion current was observed, creating an opportunity for modulation and gating of the ion current with a laser pulse. It was found that with the available low power (≈115 W∕cm(2)) IR laser, current densities as high as 0.8 mA∕cm(2) could be achieved with a 2.8 mm diameter source. Various approaches for scaling to a larger (10 cm diameter) source and the application of short pulse, high power lasers are discussed. The results and conclusions of this paper may apply to various species of hot-plate ion sources.

Histopathological alterations in post-infectious irritable bowel syndrome in Bangladeshi population

Irritable bowel syndrome (IBS) is the most common gastrointestinal disorder encountered in general practice. Although enormous progress in the pathogenesis of IBS has been made, it is still poorly understood. A significant proportion of patients with IBS, report onset of symptoms following an episode of acute gastroenteritis. Aim of the study was to determine whether post infective irritable bowel syndrome (PI-IBS) has histological or clinical features that are distinct from those of IBS patients with no history of preceding infection. A total of 50 consecutive IBS out patients and 10 healthy control subjects completed a questionnaire detailing symptoms, mode of onset, and previous psychiatry history. All underwent a full diagnostic workup including colonic biopsy and histopathology. Patients were divided according to onset of symptoms into post infectious IBS (PI-IBS, N=18) and non-post infectious IBS (non-PI-IBS, N=32) patients. Diarrhea predominantly occurred more frequently in PI- IBS (70%) than in non-PI-IBS (40%) patients (p<0.05). Histopathological examination of the biopsy specimen from the sigmoid colon of the observed individuals showed a significant increase in the number of chronic inflammatory cells in both groups of IBS patients comparing to the control group (p<0.001). Lymphoid follicles were increased in both groups of IBS patients in comparison to control group (p<0.05). Mast cells were increased in IBS patients comparing to the control group (p<0.05) and it was significantly increased in the PI-IBS patients than the non-PI-IBS patients (p<0.001). Individuals with PI-IBS are clinically distinct subgroup characterized by predominant diarrheal symptoms and increased mast cells compared to those with non PI-IBS.

Sero-epidemiology of sporadic acute hepatitis in Bangladesh: high prevalences of infection with type-B, type-E and multiple types of hepatitis virus

In a recent investigation of hepatitis in Bangladesh, the sera from 74 adult patients (aged 15-67 years) who had been clinically diagnosed as cases of sporadic acute hepatitis were collected at various hospitals in and around Dhaka. Five cases were positive for IgM antibody against the hepatitis A virus and 30 were positive both for the surface antigen of the hepatitis B virus (HBV) and for IgM antibody against the HBV core (HBc). The six cases found positive for antibodies against the hepatitis D virus were all also positive for the HBV surface antigen but negative for anti-HBc IgM. Thirteen patients harboured hepatitis C virus RNA and 29 were positive for IgM antibody against the hepatitis E virus (HEV). There were 14 non-A-to-E subjects, whose illness was of unknown aetiology. Of the 83 infections with hepatitis viruses detected in the other 60 patients, 6%, 36%, 16%, 7% and 35% were of types A, B, C, D and E, respectively. Each of 28 of the patients (47% of those confirmed to have viral hepatitis) had concomitant infection with more than one type of hepatitis virus. The predominance of HBV and HEV infections and the high prevalence of multiple infection seen among these Bangladeshi cases have not been observed among hepatitis cases in developed countries.

Variable stiffness colonoscope versus regular adult colonoscope: meta-analysis of randomized controlled trials

BACKGROUND AND STUDY AIMS

The variable stiffness colonoscope (VSC) may have theoretical advantages over standard adult colonoscopes (SACs), though data are conflicting. We conducted a meta-analysis to compare the efficacies of the VSC and SAC.

STUDY DESIGN

We searched Medline (1966 - 2008) and abstracts of gastroenterology scientific meetings in the 5 years to February 2008, only for randomized clinical trials (RCTs) of adult patients. Trial quality was assessed using the Delphi list. In a meta-analysis with a fixed effects model, cecal intubation rates, cecal intubation times, abdominal pain scores, sedation used, and use of ancillary maneuvers, were compared in separate analyses, using weighted mean differences (WMDs), standardized mean differences (SMDs), or odds ratios (ORs).

RESULTS

Seven RCTs satisfied the inclusion criteria (1923 patients), four comparing VSC with SAC procedures in adults, and three evaluating the pediatric VSC. There was no significant heterogeneity among the studies. The overall trial quality was adequate. Cecal intubation rate was higher with the use of VSC (OR = 2.08, 95 % confidence interval [CI] 1.29 to 3.36). The VSC was associated with lower abdominal pain scores and a decreased need for sedation during colonoscopy. Cecal intubation time was similar for the two colonscope types (WMD = - 0.21 minutes, 95 % CI - 0.85 to 0.43). Because of the nature of the intervention no studies were blinded. There was no universal method for using the VSC.

CONCLUSIONS

Compared with the SAC, VSC use was associated with a higher cecal intubation rate, less abdominal pain, and decreased need for sedation. However, cecal intubation times were similar for the two colonoscope types.