Serosurveillance among urban slum and non-slum populations immunized with COVID-19 vaccines in Bangladesh.

Using two rounds of serosurveillance, we aimed to observe the COVID-19 vaccination status and the dynamics of antibody responses to different vaccines among urban slum and non-slum populations of Bangladesh. Adults (>18 years) and children (10-17 years) were enrolled in March and October 2022. Data including COVID-19 vaccine types and dosage uptake were collected. SARS-CoV-2 spike (S)-specific antibodies were measured in blood. The proportion of vaccinated children was significantly lower among slum than non-slum populations. Two doses of vaccines showed an increase in the level of anti-S-antibodies up to 2 months, followed by reduced levels at 2-6 months and a resurgence at 6-12 months. Children showed significantly higher anti-S-antibodies after two doses of the Pfizer-BioNTech vaccine than adults; however, after 6 months, the level of antibodies declined in younger children (10 - < 12 years). In a mixed vaccine approach, mRNA vaccines contributed to the highest antibody response whether given as the first two doses or as the third dose. Our findings emphasized the need for increasing the coverage of COVID-19 vaccination among slum children and booster dosing among all children. The use of mRNA vaccines in the mixed vaccination approach was found to be useful in boosting the antibody response to SARS-CoV-2.

Insight into the function of a unique voltage-sensor protein (TMEM266) and its short form in mouse cerebellum.

Voltage-sensing proteins generally consist of voltage-sensor domains and pore-gate domains, forming the voltage-gated ion channels. However, there are several unconventional voltage-sensor proteins that lack pore-gate domains, conferring them unique voltage-sensing machinery. TMEM266, which is expressed in cerebellum granule cells, is one of the interesting voltage-sensing proteins that has a putative intracellular coiled-coil and a functionally unidentified cytosolic region instead of a pore-gate domain. Here, we approached the molecular function of TMEM266 by performing co-immunoprecipitation experiments. We unexpectedly discovered that TMEM266 proteins natively interact with the novel short form splice variants that only have voltage-sensor domains and putative cytosolic coiled-coil region in cerebellum. The crystal structure of coiled-coil region of TMEM266 suggested that these coiled-coil regions play significant roles in forming homodimers. In vitro expression experiments supported the idea that short form TMEM266 (sTMEM266) or full length TMEM266 (fTMEM266) form homodimers. We also performed proximity labeling mass spectrometry analysis for fTMEM266 and sTMEM266 using Neuro-2A, neuroblastoma cells, and fTMEM266 showed more interacting molecules than sTMEM266, suggesting that the C-terminal cytosolic region in fTMEM266 binds to various targets. Finally, TMEM266-deficient animals showed the moderate abnormality in open-field test. The present study provides clues about the novel voltage-sensing mechanism mediated by TMEM266.

Self-interaction error overbinds water clusters but cancels in structural energy differences.

We gauge the importance of self-interaction errors in density functional approximations (DFAs) for the case of water clusters. To this end, we used the Fermi-Löwdin orbital self-interaction correction method (FLOSIC) to calculate the binding energy of clusters of up to eight water molecules. Three representative DFAs of the local, generalized gradient, and metageneralized gradient families [i.e., local density approximation (LDA), Perdew-Burke-Ernzerhof (PBE), and strongly constrained and appropriately normed (SCAN)] were used. We find that the overbinding of the water clusters in these approximations is not a density-driven error. We show that, while removing self-interaction error does not alter the energetic ordering of the different water isomers with respect to the uncorrected DFAs, the resulting binding energies are corrected toward accurate reference values from higher-level calculations. In particular, self-interaction-corrected SCAN not only retains the correct energetic ordering for water hexamers but also reduces the mean error in the hexamer binding energies to less than 14 meV/[Formula: see text] from about 42 meV/[Formula: see text] for SCAN. By decomposing the total binding energy into many-body components, we find that large errors in the two-body interaction in SCAN are significantly reduced by self-interaction corrections. Higher-order many-body errors are small in both SCAN and self-interaction-corrected SCAN. These results indicate that orbital-by-orbital removal of self-interaction combined with a proper DFA can lead to improved descriptions of water complexes.

Roles of the polybasic furin cleavage site of spike protein in SARS-CoV-2 replication, pathogenesis, and host immune responses and vaccination.

The polybasic furin cleavage site insertion with four amino acid motifs (PRRA) in spike protein's S1/S2 junction site is important in determining viral infectivity, transmission, and host range. However, there is no review so far explaining the effect of the furin cleavage site of the spike protein on SARS-CoV-2 replication and pathogenesis in the host and immune responses and vaccination. Therefore, here we specifically focused on genomic evolution and properties of the cleavage site of spike protein in the context of SARS-CoV-2 followed by its effect on viral entry, replication, and pathogenesis. We also explored whether the spike protein furin cleavage site affected the host immune responses and SARS-CoV-2 vaccination. This review will help to provide novel insights into the effects of polybasic furin cleavage site on the current COVID-19 pandemic.

Phytomedicines to Target Hepatitis B Virus DNA Replication: Current Limitations and Future Approaches.

Hepatitis B virus infection (HBV) is one of the most common causes of hepatitis, and may lead to cirrhosis or hepatocellular carcinoma. According to the World Health Organization (WHO), approximately 296 million people worldwide are carriers of the hepatitis B virus. Various nucleos(t)ide analogs, which specifically suppress viral replication, are the main treatment agents for HBV infection. However, the development of drug-resistant HBV strains due to viral genomic mutations in genes encoding the polymerase protein is a major obstacle to HBV treatment. In addition, adverse effects can occur in patients treated with nucleos(t)ide analogs. Thus, alternative anti-HBV drugs of plant origin are being investigated as they exhibit excellent safety profiles and have few or no side effects. In this study, phytomedicines/phytochemicals exerting significant inhibitory effects on HBV by interfering with its replication were reviewed based on different compound groups. In addition, the chemical structures of these compounds were developed. This will facilitate their commercial synthesis and further investigation of the molecular mechanisms underlying their effects. The limitations of compounds previously screened for their anti-HBV effect, as well as future approaches to anti-HBV research, have also been discussed.

Heterogeneity of microglial proton channel in different brain regions and its relationship with aging.

The properties of microglia largely differ depending on aging as well as on brain regions. However, there are few studies that investigated the functional importance of such heterogeneous properties of microglia at the molecular level. Voltage-gated proton channel, Hv1/VSOP, could be one of the candidates which confers functional heterogeneity among microglia since it regulates brain oxidative stress in age-dependent manner. In this study, we found that Hv1/VSOP shows brain region-dependent heterogeneity of gene expression with the highest level in the striatum. We studied the importance of Hv1/VSOP in two different brain regions, the cerebral cortex and striatum, and examined their relationship with aging (using mice of different ages). In the cortex, we observed the age-dependent impact of Hv1/VSOP on oxidative stress, microglial morphology, and gene expression profile. On the other hand, we found that the age-dependent significance of Hv1/VSOP was less obvious in the striatum than the cortex. Finally, we performed a battery of behavioral experiments on Hv1/VSOP-deficient mice both at young and aged stages to examine the effect of aging on Hv1/VSOP function. Hv1/VSOP-deficient mice specifically showed a marked difference in behavior in light/dark transition test only at aged stages, indicating that anxiety state is altered in aged Hv1/VSOP mice. This study suggests that a combination of brain region heterogeneity and animal aging underscores the functional importance of Hv1/VSOP in microglia.

Regulation of hepatic oxidative stress by voltage-gated proton channels (Hv1/VSOP) in Kupffer cells and its potential relationship with glucose metabolism.

Voltage-gated proton channels (Hv1/VSOP), encoded by Hvcn1, are important regulator of reactive oxygen species (ROS) production in many types of immune cells. While in vitro studies indicate that Hv1/VSOP regulates ROS production by maintaining pH homeostasis, there are few studies investigating the functional importance of Hv1/VSOP in vivo. In the present study, we first show that Hv1/VSOP is functionally expressed in liver resident macrophage, Kupffer cells, regulating the hepatic oxidative stress in vivo. Our immunocytochemistry and electrophysiology data showed that Hvcn1 is specifically expressed in Kupffer cells, but not in hepatocytes. Furthermore, Hvcn1-deficiency drastically altered the hepatic oxidative stress. The Hvcn1-deficient mice showed high blood glucose and serum insulin but normal insulin sensitivity, indicating that these phenotypes were not linked to insulin resistance. Transcriptome analysis indicated that the gene expression of glycogen phosphorylase (Pygl) and Glucose-6-phosphatase, catalytic subunit (G6pc) were upregulated in Hvcn1-deficient liver tissues, and quantitative PCR confirmed the result for Pygl. Furthermore, we observed higher amount of glucose-6-phosphate, a key sugar intermediate for glucose in Hvcn1-deficient liver than WT, suggesting that glucose production in liver is accelerated in Hvcn1-deficient mice. The present study sheds light on the functional importance of Kupffer cells in hepatic oxidative stress and its potential relationship with glucose metabolism.

How well do self-interaction corrections repair the overestimation of static polarizabilities in density functional calculations?

We examine the effect of removing self-interaction error (SIE) on the calculation of molecular polarizabilities in the local spin density (LSDA) and generalized gradient approximations (GGA). To this end, we utilize a database of 132 molecules taken from a recent benchmark study [Hait and Head-Gordon, Phys. Chem. Chem. Phys., 2018, 20, 19800] to assess the influence of SIE on polarizabilities by comparing results with accurate reference data. Our results confirm that the general overestimation of molecular polarizabilities by these density functional approximations can be attributed to SIE. However, removing SIE using the Perdew-Zunger self-interaction-correction (PZ-SIC) method, implemented using the Fermi-Löwdin Orbital SIC approach, leads to an underestimation of molecular polarizabilities, showing that PZ-SIC overcorrects when combined with LSDA or GGA. Application of a recently proposed locally scaled SIC [Zope, et al., J. Chem. Phys., 2019, 151, 214108] is found to provide more accurate polarizabilities. We attribute this to the ability of the local scaling scheme to selectively correct for SIE in the regions of space where the correction is needed most.

Static dipole polarizabilities of polyacenes using self-interaction-corrected density functional approximations.

Density functional approximations (DFAs) are known to significantly overestimate the polarizabilities of long chain-like molecules. We study the static electric dipole polarizabilities and the vertical ionization potentials of polyacenes from benzene to pentacene using the Fermi-Löwdin orbital-based self-interaction corrected (FLOSIC) density functional method. The orbital by orbital self-interaction correction corrects for the overestimation tendency of DFAs. The polarizabilities calculated with FLOSIC-DFA are, however, overly corrected. We also tested the recently developed locally scaled self-interaction correction (LSIC) method on polyacenes. The local-scaling method applies full SIC in the one-electron regions and restores the proper behavior of the SIC exchange-correlation functionals in the uniform density limit. The results show that LSIC removes the overcorrection tendency of the FLOSIC-DFA and produces results that are in excellent agreement with reference coupled-cluster single and double values. The vertical ionization potentials with LSIC also show good agreement with available experimental values.

Efficient photodynamic therapy against drug-resistant prostate cancer using replication-deficient virus particles and talaporfin sodium.

To enhance the potency of photosensitizer, we developed a novel photosensitizer, Laserphyrin®-HVJ-E (L-HVJ-E), by incorporating talaporfin sodium (Laserphyrin®, Meiji Seika Pharma) into hemagglutinating virus of Japan envelope (HVJ-E). In this study, we examined the optimal Laserphyrin® concentration for preparation of Laserphyrin®-HVJ-E which had photocytotoxicity and maintained direct cytotoxicity derived from HVJ-E. Then, potency of Laserphyrin®-HVJ-E and Laserphyrin® were compared in vitro using castration-resistant prostate cancer cell line (PC-3). A laser diode (L660P120, Thorlabs, USA) with a wavelength of 664 nm was used for light activation of Laserphyrin®, which corresponds to an absorption peak of Laserphyrin® and provides a high therapeutic efficiency. The photocytotoxicity and direct cytotoxicity of Laserphyrin®-HVJ-E prepared using various Laserphyrin® concentrations were evaluated using PC-3 cell in vitro. We categorized the treatment groups as Group 1: 50 µL of D-MEM treatment group, Group 2: HVJ-E treatment group, Group 3: Laserphyrin®-HVJ-E treatment group, and Group 4: Laserphyrin® treatment group. Group 3 was subjected to different concentrations of Laserphyrin®-HVJ-E suspension, and all groups were subjected to different incubation periods (24, 48 h), (30 min, 1 h, or 3 h,) respectively, without and after PDT. Laserphyrin®-HVJ-E prepared using 15 mM Laserphyrin® had high photocytotoxicity and maintained HVJ-E's ability to induce direct cytotoxicity. Therapeutic effect of Laserphyrin®-HVJ-E was substantially equivalent to that of Laserphyrin® alone even at half Laserphyrin® concentration. By utilizing Laserphyrin®-HVJ-E, PDT could be performed with lower Laserphyrin® concentration. In addition, Laserphyrin®-HVJ-E showed higher potency than Laserphyrin® by combining cytotoxicities of HVJ-E and PDT.

Sustained release of curcumin self-emulsifying drug delivery system (SEDDS) from solvent-cast Soluplus® films.

The objective of the present study was to investigate the feasibility of formulating and loading Curcumin SEDDS (Self-Emulsified Drug Delivery Systems) into films made from Soluplus® as the film-forming polymer. Films with up to 30% of Curcumin SEDDS were prepared by the solvent casting technique and analyzed for their mechanical and dissolution properties. A nine-run, two-factor, three-level factorial design was utilized to investigate the effect of SEDDS load (10, 20, and 30% w/w) and film thickness (10, 25, and 40 mils) on the tensile strength, elongation, and adhesiveness of the films. The dissolution profile of the films was also investigated by a USP Type 1 method. SEDDS loading was found to plasticize Soluplus® and to yield transparent films of good mechanical properties. Increasing SEDDS load, however, was found to reduce the tensile strength of the films, while increasing their adhesiveness and elongation. On the other hand, while an increase in film thickness was found to increase the tensile strength of the films, it reduced the elongation capacity of the films. Loading SEDDS into Soluplus® films was also found to sustain their release over 6 h, where a significant delay in release was found at lower SEDDS loads. This study demonstrated that Soluplus® can be used not only to formulate SEDDS into polymeric films but also to sustain their release over an extended time.

Obesity and pain: a systematic review.

BACKGROUND/OBJECTIVES: The current systematic review considered research published within the 10 years preceding June 2019, dealing with the topic of obesity and pain. Within the context of the complex biological and behavioral interrelationships among these phenomena, we sought to identify gaps in the literature and to highlight key targets for future transdisciplinary research. The overarching inclusion criteria were that the included studies could directly contribute to our understanding of these complex phenomena. METHODS: We searched PubMed/Medline/Cochrane databases dating back 10 years, using the primary search terms "obesity" and "pain," and for a secondary search we used the search terms "pain" and "diet quality." RESULTS: Included studies (n = 70) are primarily human; however, some animal studies were included to enhance understanding of related basic biological phenomena and/or where human data were absent or significantly limited. CONCLUSIONS: Our overall conclusions highlight (1) the mechanisms of obesity-related pain (i.e., mechanical, behavioral, and physiological) and potential biological and behavioral contributors (e.g., gender, distribution of body fat, and dietary factors), (2) the requirement for accurate and reliable objective measurement, (3) the need to integrate biological and behavioral contributors into comprehensive, well-controlled prospective study designs.

Study of self-interaction errors in density functional predictions of dipole polarizabilities and ionization energies of water clusters using Perdew-Zunger and locally scaled self-interaction corrected methods.

We studied the effect of self-interaction error (SIE) on the static dipole polarizabilities of water clusters modeled with three increasingly sophisticated, non-empirical density functional approximations (DFAs), viz., the local spin density approximation (LDA), the Perdew-Burke-Ernzerhof (PBE) generalized-gradient approximation (GGA), and the strongly constrained and appropriately normed (SCAN) meta-GGA, using the Perdew-Zunger self-interaction-correction (PZ-SIC) energy functional in the Fermi-Löwdin orbital SIC framework. Our results show that while all three DFAs overestimate the cluster polarizabilities, the description systematically improves from LDA to PBE to SCAN. The self-correlation free SCAN predicts polarizabilities quite accurately with a mean absolute error (MAE) of 0.53 bohr3 with respect to coupled cluster singles and doubles (CCSD) values. Removing SIE using PZ-SIC correctly reduces the DFA polarizabilities, but overcorrects, resulting in underestimated polarizabilities in SIC-LDA, SIC-PBE, and SIC-SCAN. Finally, we applied a recently proposed locally scaled SIC (LSIC) method using a quasi self-consistent scheme and using the kinetic energy density ratio as an iso-orbital indicator. The results show that the LSIC polarizabilities are in excellent agreement with mean absolute errors of 0.08 bohr3 for LSIC-LDA and 0.06 bohr3 for LSIC-PBE with most recent CCSD polarizabilities. Likewise, the ionization energy estimates as absolute of highest occupied energy eigenvalue predicted by LSIC are also in excellent agreement with CCSD(T) ionization energies with MAEs of 0.4 eV for LSIC-LDA and 0.06 eV for LSIC-PBE. The LSIC-LDA predictions of ionization energies are comparable to the reported GW ionization energies, while the LSIC-PBE ionization energies are more accurate than the reported GW results.

Arf GTPase-Activating proteins ADAP1 and ARAP1 regulate incorporation of CD63 in multivesicular bodies.

Arf GTPase-activating proteins (ArfGAPs) mediate the hydrolysis of GTP bound to ADP-ribosylation factors. ArfGAPs are critical for cargo sorting in the Golgi-to-ER traffic. However, the role of ArfGAPs in sorting into intralumenal vesicles (ILVs) in multivesicular bodies (MVBs) in post-Golgi traffic remains unclear. Exosomes are extracellular vesicles (EVs) of endosomal origin. CD63 is an EV marker. CD63 is enriched ILVs in MVBs of cells. However, the secretion of CD63 positive EVs has not been consistent with the data on CD63 localization in MVBs, and how CD63-containing EVs are formed is yet to be understood. To elucidate the mechanism of CD63 transport to ILVs, we focused on CD63 localization in MVBs and searched for the ArfGAPs involved in CD63 localization. We observed that ADAP1 and ARAP1 depletion inhibited CD63 localization to enlarged endosomes after Rab5Q79L overexpression. We tested epidermal growth factor (EGF) and CD9 localization in MVBs. We observed that ADAP1 and ARAP1 depletion inhibited CD9 localization in enlarged endosomes but not EGF. Our results indicate ADAP1 and ARAP1, regulate incorporation of CD63 and CD9, but not EGF, in overlapped and different MVBs. Our work will contribute to distinguish heterogenous ILVs and exosomes by ArfGAPs.

Enhancing effects of Aloe vera gel extracts on the humoral and cellular immune response and growth performance in broiler chickens.

Objective: The experiment evaluated how Aloe vera gel (AVG) extract supplementation affected immune responses and physiological performances in broiler chickens. Materials and Methods: 90-day-old Cobb 500 broiler chicks were reared for 38 days without the addition of antibiotics, either through feed or water. At 10 days, chicks were allocated into three groups: A, B, and C (n = 30). Group A served as non-supplemented control. Groups B and C were administered aqueous extracts of AVG at 1.0% and 2.0%, respectively, with drinking water. Results: The supplementation of AVG potentiated the chicken immune response to Newcastle disease-vaccinated birds and sheep red blood cell-treated birds, which detected the highest antibody titers against Newcastle disease virus and sRBC. The cellular immune response evaluated through a cutaneous basophilic hypersensitivity test using phytohemagglutinin-P demonstrated a significant increase in skin thickness in AVG-supplemented birds. The relative sizes of lymphoid organs (bursa, spleen, and thymus) were significantly enhanced (p < 0.05) among the groups. Broilers given AVG-1 and AVG-2 exhibited significantly greater (p < 0.01) live body weight, dressing percentages, and serum protein and serum albumin levels. The supplemented groups experienced a significant reduction in total serum cholesterol, triglycerides, and low-density lipoprotein-cholesterol values, while the levels of high-density lipoprotein-cholesterol remained unchanged. The dietary aqueous extracts of AVG are effective in enhancing innate and specific immunity. Conclusion: This work strengthens the perspective of the use of AVG as an immune stimulant to facilitate recovery from immune suppression states, enhance innate and specific immunity, and improve broiler growth performance.

Ecotoxicological effects of cypermethrin on indigenous climbing perch (Anabas testudineus).

Pesticides including cypermethrin (10% EC) are commonly used pesticide in tea gardens of Bangladesh possess distinct harmful effects on an aquatic community. The experiment was carried out to assess the ecotoxicological effects of cypermethrin (10%) concentrate on indigenous Climbing Perch (Anabas testudineus). A total of 120 A. testudineus (mean length 16 ± 2.67 cm and mean weight 31.6 ± 3.56 g) were exposed to the acute toxicity test when the lethal concentration 50 value (LC50) for 96 h was maintained at 1.00 ppm. Three different sub-lethal concentrations of 0.05 ppm (5%), 0.10 ppm (10%), and 0.20 ppm (20%) were used respectively as three treatments and a control of 0 ppm with three replicates each. Restlessness, erratic movement, increased opercular activities, loss of equilibrium, and irregular response to feeding were observed in all the treatments compared to control one. Concerning histopathological alterations, all the analyzed organs showed highest changes in the T3 (cypermethrin conc. 20%) compared to other treatments while T0 (0 ppm) had normal structure. The major changes in the gill were epithelial cell hyperplasia, necrosis, severe lamellar fusion and epithelial lifting; while necrotic proximal tubules, glomerular shrinkage, disrupted renal corpuscle of the kidney and nuclear pyknosis, degenerated hepatic cells and vacuolation were observed in the liver. Severe melanomacrophage centre (MMC), haemosiderosis and vacuolation were found in spleen. The effect of cypermethrin on the hematological parameters of experimental fish was also studied. Red blood cells, hemoglobin and hematocrit were decreased in the experimental groups and lowest value was in T3 while values of white blood cells were increased in the experimental groups compared to control one. Hence, the present observation revealed that pesticides even at low concentrations can cause harmful effects on A. testudineus.

Fetal femur length and risk of diabetes in adolescence: a prospective cohort study.

BACKGROUND: Diabetes is more apparent in adulthood but may be dormant in childhood and originates during early fetal development. In fetal biometry, femur length (FL) is crucial for assessing fetal growth and development. This study aimed to assess potential associations between fetal femur growth and prediabetic biomarkers in Bangladeshi children. METHODS: A cohort study embedded in a population-based maternal food and micronutrient supplementation (MINIMat) trial was conducted in Matlab, Bangladesh. The children in the cohort were followed up until 15 years of age. In the original trial, pregnancy was confirmed by ultrasound before 13 gestational weeks (GWs). Afterward, ultrasound assessments were performed at 14, 19, and 30 GWs. FL was measured from one end to the other, capturing a complete femoral image. The FL was standardized by GW, and a z-score was calculated. FBG and HbA1c levels were determined in plasma and whole blood, and the triglyceride-glucose index, a biomarker of insulin resistance, was calculated as Ln [fasting triglycerides (mg/dl) × fasting glucose (mg/dl)/2]. Multivariable linear regression analysis using a generalized linear model was performed to estimate the effects of FL at 14, 19 and 30 GWs on prediabetic biomarkers at 9 and 15 years of age. Maternal micronutrient and food supplementation group, parity, child sex, and BMI at 9 years or 15 years were included as covariates. RESULTS: A total of 1.2% (6/515) of the participants had impaired fasting glucose during preadolescence, which increased to 3.5% (15/433) during adolescence. At 9 years, 6.3% (32/508) of the participants had elevated HbA1c%, which increased to 28% (120/431) at 15 years. Additionally, the TyG index increased from 9.5% (49/515) (during preadolescence) to 13% (56/433) (during adolescence). A one standard deviation decrease in FL at 14 and 19 GWs was associated with increased FBG (ß = - 0.44 [- 0.88, - 0.004], P = 0.048; ß = - 0.59 [- 1.12, - 0.05], P = 0.031) and HbA1c (ß = - 0.01; [- 0.03, -0.005], P = 0.007; ß = - 0.01 [- 0.03, - 0.003], P = 0.018) levels at 15 years. FL was not associated with diabetic biomarkers at 9 years. CONCLUSION: Mid-trimester impaired femur growth may be associated with elevated prediabetic biomarkers in Bangladeshi adolescents.

Comprehensive analysis of antigenic variations and genomic properties of hepatitis B virus in clinical samples in the mid-north east region of Bangladesh.

This investigation delineates an exhaustive analysis of the clinical, immunological, and genomic landscapes of hepatitis B virus (HBV) infection across a cohort of 22 verified patients. The demographic analysis unveiled a pronounced male bias (77.27%), with patient ages spanning 20 to 85 years and durations of illness ranging from 10 days to 4 years. Predominant clinical manifestations included fever, fatigue, anorexia, abdominal discomfort, and arthralgia, alongside observed co-morbidities such as chronic renal disorders and hepatocellular carcinoma. Antigenic profiling of the HBV envelope proteins elucidated significant heterogeneity among the infected subjects, particularly highlighted by discordances in the detection capabilities of small and large HBsAg assays, suggesting antigenic diversity. Quantitative assessment of viral loads unveiled a broad spectrum, accompanied by atypical HBeAg reactivity patterns, challenging the reliability of existing serological markers. Correlative studies between viral burden and antigenicity of the envelope proteins unearthed phenomena indicative of diagnostic evasion. Notably, samples demonstrating robust viral replication were paradoxically undetectable by the large HBsAg ELISA kit, advocating for more sophisticated diagnostic methodologies. Genotypic examination of three HBV isolates classified them as genotype D (D2), with phylogenetic alignment to strains from various global origins. Mutational profiling identified pivotal mutations within the basic core promoter and preS2/S1 regions, associated with an augmented risk of hepatocellular carcinoma. Further, mutations discerned in the small HBsAg and RT/overlap regions were recognized as contributors to vaccine and/or diagnostic escape mechanisms. In summation, this scholarly discourse elucidates the intricate interplay of clinical presentations, antigenic diversity, and genomic attributes in HBV infection, accentuating the imperative for ongoing investigative endeavors to refine diagnostic and therapeutic modalities.

Zoonotic human liver flukes, a type 1 biocarcinogen, in freshwater fishes: genetic analysis and confirmation of molluscan vectors and reservoir hosts in Bangladesh.

BACKGROUND: Opisthorchiid flukes, particularly Opisthorchis viverrini, Opisthorchis felineus, Clonorchis sinensis, and Metorchis spp. are the most common fish-borne zoonotic human liver flukes (hLFs). Liver fluke infections are more prevalent in resource-deprived and underprivileged areas. We herein estimated the prevalence of the metacercariae (MC) of major hLFs in common large freshwater fishes (lFWF) marketed for human consumption from some selected areas of Bangladesh along with detection of their molluscan vectors and reservoirs. METHODS: The current status of fish-borne zoonotic hLF infections in lFWF was investigated along with their molluscan vectors and mammalian reservoir hosts in Mymensingh and Kishoreganj in Bangladesh from July 2018-June 2022 using conventional and multiple molecular techniques, such as PCR, PCR-restriction fragment length polymorphism (RFLP), sequencing, and bioinformatic analyses. The infection rate of fishes was analyzed using the Z-test and the loads of MC were compared using the chi-squared (χ2) test. RESULTS: The MC of C. sinensis, Opisthorchis spp., and Metorchis spp. were detected in 11 species of common and popular lFWF. In lFWF, the estimated prevalence was 18.7% and the mean load was 137.4 ± 149.8 MC per 100 g of fish. The prevalence was the highest (P < 0.05) in spotted snakehead fishes (Channa punctata, 63.6%). The highest rate of infection (P < 0.05) was observed with the MC of C. sinensis (11.8%). Metacercariae were almost equally (P > 0.05) distributed between the head and body of fishes. The infection rate was slightly higher in cultured (19.6%) fishes. The MC of C. sinensis, O. felineus, O. viverrini, and Metorchis orientalis in fishes were confirmed using PCR, PCR-RFLP and bioinformatics. The cercariae of opisthorchiid (Pleurolophocercus cercariae) flukes were only recovered from Bithynia spp. (3.9%, 42 out of 1089). The ova of hLFs from dogs (4.3%, 5 out of 116) and cats (6.0%, 6 out of 100), and adult flukes (M. orientalis) from ducks (41.1% 113 out of 275) were detected. CONCLUSIONS: The MC of hLFs are highly prevalent in fresh water fishes in Bangladesh. Reservoir hosts, such as street dogs, cats, and ducks carried the patent infection, and residents of Bangladesh are at risk.