Biology subjects

Hossain, M. T.

Publications and source records attributed to Hossain, M. T..

9 recordsLinked to original sources

bioRxiv2026

Probabilistic dietary exposure modeling and health risk assessment of heavy metals via the fodder-cattle-human continuum in Bangladesh

Dietary exposure to heavy metals (HMs) via animal-source foods is a critical environmental health pathway. In rapidly industrializing Bangladesh, contamination of the bovine food chain from agricultural feeds and industrial emissions poses an unquantified public health burden. This study evaluated exposure pathways, spatial distribution, mass-transfer dynamics, and health risks of six HMs (Cr, Cu, Cd, Pb, As, and Hg) across the fodder-cattle-human continuum. Samples of beef (n = 76), raw milk (n = 76), commercial cattle feed (n = 40), and fodder (n = 88) were collected from eight sites across industrial and non-industrial zones in Bangladesh and analysed by atomic absorption spectroscopy. Probabilistic Monte Carlo simulations (10,000 iterations) quantified estimated daily intake, target hazard quotients (THQ), cumulative hazard index (HI), and lifetime carcinogenic risk (CR) for adult and pediatric receptors. Copper (Cu) was the dominant contaminant across all matrices, peaking in beef (103.89 {+/-} 15.87 mg/kg) and milk (13.67 {+/-} 1.53 mg/L). Spatial analysis revealed distinct contamination profiles: Pb burden peaked in industrial zones while Cr was elevated in non-industrial sectors. Monte Carlo modelling identified commercial feed as the most efficient transfer vector into beef. Pediatric THQ for Cu significantly exceeded the safety threshold (THQ > 1), and upper-bound lifetime carcinogenic risk from As approached the critical USEPA 10- regulatory ceiling. These findings demonstrate that industrial and agricultural externalities efficiently contaminate the bovine food supply chain in Bangladesh, with copper and arsenic representing the most critical non-carcinogenic and carcinogenic dietary hazards, respectively. Children are disproportionately vulnerable due to lower body weight. The results underscore the need for targeted upstream interventions in commercial feed production and provide evidence to support feed-quality regulation and environmental monitoring in rapidly industrializing settings.

pharmacology and toxicology↗

bioRxiv2026

Artificial capillaries-on-a-chip with modular control over lumen size, architecture, in situ modifications and co-culture conditions.

Currently in vitro models of microvascular biology rely on self-assembly of vascular cells in compatible gels. However, the stochastic nature of this process results in large variations in lumen sizes, perfusion continuity, and shear stresses making systematic and reproducible analysis challenging. Here, we report a new technology to generate artificial capillaries on a chip with custom control over lumen sizes and architectures using a combination of femtosecond laser cavitation and collagen casting within multi-chambered microfluidic chips. The design allows seeding of endothelial cells within capillary-sized microchannels and seeding of stromal cells within top-open silos, with independent control over seeding sequence and media compositions. Results show that endothelialized microchannels, coined as artificial capillaries, exhibit excellent barrier function with reproducible control over lumen sizes ({phi}=8-35{micro}m) and their architectures (straight, curvatures, tapered, branched). The physical flow parameters measured across the lumen (namely, flow shear) and at the channel outlets (flow velocities) have been validated against high-fidelity numerical assessments from the Large Eddy Simulation scheme within the digitized versions of the microchannels. The experiment-computation compatibility enabled us to predict changes in regional velocity and wall shear stresses within artificial capillaries, for various capillary architectures. We also show that in situ editing of artificial capillaries in the form of adding new branches or adding occlusions is possible. Lastly, we developed a co-culture model which enables the study of stromal cells with artificial capillaries using conventional imaging methods. We envision that acellular chips with two seeding ports can be readily shipped worldwide and could potentially be adopted as a new technology to study microvascular biology in a reproducible manner.

bioengineering↗

bioRxiv2025

Molecular Plasticity of T Cells Informs Their Possible Adaptation in 4T1 Tumors

BackgroundThe triple-negative breast cancer (TNBC) microenvironment (TME) undergoes progressive reprogramming, transitioning from an early immune-active state to a late immune-suppressed state. While tumor cell plasticity has been extensively studied, the molecular plasticity of T cells in vivo remains poorly defined. ObjectivesTo characterize transcriptional changes in T cells during TNBC progression and identify stage-specific shifts in T cell function, polarization, and antigen-presenting cell (APC)-T cell interactions. ResultsTranscriptional analysis of T cells from BALB/c mice bearing 4T1 tumors at 1, 3, and 6 weeks revealed a decline in T cell-associated genes from 194 at 1 week to 156 at 6 weeks, with a significant late-stage loss of TCR diversity and contraction of natural killer T (NKT)- and {gamma}{delta} T cell-related transcripts. Cytokine and transcription factor dynamics reflected temporal T cell polarization: early (1 week) IL-12/{beta}-STAT4 signaling supports CD4+ type 1 T helper cell (Th1) and type 1 CD8+ cytotoxic T cell (Tc1) responses; intermediate (3 weeks) IL-21 and BCL6 expression suggest transient CD8+ cytotoxic follicular T cell (Tfc) skewing; and late (6 weeks) AhR and IL-1{beta} induction reflect interleukin 17/22 producing CD8+ T cell (Tc17/Tc22) transition. Pro-inflammatory cytokines and chemokines increased over time, while immunosuppressive mediators (e.g., IL-10) declined significantly. Antigen-presenting cell (APC)-T cell crosstalk deteriorated at 6 weeks, characterized by a reduction in the expression of co-stimulatory and APC genes. Despite an early dominance of M1-like macrophage signals (e.g., IL-12/{beta}), persistent expression of arginase 1 (ARG1) and other M2-associated genes indicated a stable tolerogenic niche. ConclusionsTNBC progression is characterized by progressive T cell functional decline, narrowing of TCR diversity, impaired APC-T cell interactions, and sustained macrophage-driven immunosuppression. These temporally coordinated immune shifts suggest tumor-driven adaptation toward immune evasion and identify potential windows for stage-specific immunotherapeutic intervention.

cancer biology↗

bioRxiv2025

Molecular Phenotypic Plasticity Informs Possible Adaptive Change of Triple-Negative Breast Cancer Cells In Vivo

Background and ObjectivesCancer evolves via interconnected mechanisms, including changes in extrachromosomal DNA (ecDNA), genetic instability, and interactions with the tumor microenvironment (TME). These mechanisms allow for some clones to evolve metastatic traits, evade the immune system, and resist chemotherapy. However, how cancer cells evolve in vivo remains poorly understood. This study investigates the in vivo changes in gene expression of triple-negative breast cancer (TNBC) cells implanted in BALB/c mice. MethodologyWe analyzed RNA-seq data from 4T1 TNBC cells and tumors at different growth stages (1-, 3-, and 6-week) to identify differentially expressed genes, protein-protein interactions, and ecDNA alterations. We also assessed how ecDNA and genomic instability proteins interact with anti-TNBC drugs ResultsOur results reveal early transcriptional shifts within one week of tumor implantation, showing rapid acclimation. Changes in gene expression continued over time, with significant molecular reprogramming observed at six weeks under in vivo environmental pressures, including ecDNA alterations and immune evasion. The shift from the earlier generation (1 week) to the later generation (6 weeks) suggests cumulative alterations in key oncogenic pathways related to tumor progression. Additionally, we found that mutations in ecDNA and genomic instability proteins influence drug binding affinity, suggesting that adaptive changes may impact chemotherapy response. Conclusions and ImplicationsThis study provides new insights into how TNBC tumors may evolve over time and novel ecDNA-related mechanisms of possible tumor adaptation, highlighting potential biomarkers for tumor aggression and immune evasion, which could help develop more effective therapeutic strategies against TNBC.

cancer biology↗

bioRxiv2025

Assessment of the Anticancer Activity of Aegle marmelos Leaf Extracts Against Ehrlich's Ascites Carcinoma (EAC) Cell Line in Swiss Albino Mice

Cancer remains a significant health threat globally, and as a result, the demand for safer and more effective alternatives keeps growing. In this current study, we have assessed the anticancer activity of Aegle marmelos extract on Ehrlich Ascites Carcinoma (EAC) cells on Swiss Albino mice. Three extracts were prepared: a methanolic (APME), chloroform (APCE), and n-hexane (APHE) extract. These extracts were administered intraperitoneally in doses of 50 mg/kg and 100 mg/kg per dose on 6 consecutive days to mice. The anticancer activity was assessed from viable tumor cell count, with percentage (%) inhibition of cell growth, and changes in body weight of the mice that had been treated with extracts. Of all the extracts, APHE exhibited the most tumor growth inhibition (62.2% at 100 mg/kg), followed by APME (59.25%) and APCE (54.86%), compared to the standard chemotherapy drug doxorubicin (81.6% inhibition at 0.8 mg/kg/day). Mice treated with the extracts experienced less weight loss than the control group, with an approximate effect of 0.50 {+/-} 0.06 g/day. A Brine Shrimp Lethality Bioassay demonstrated a cytotoxic dose-dependent impact, with LC50 values of 18.38, 36.79, and 46.45 micrograms per milliliter for n-hexane, methanolic, and chloroform extracts, respectively. The tumor suppression and cytotoxicity effects of Aegle marmelos extracts are probably attributable to the bioactive compounds such as flavonoids, alkaloids, and essential oils that have known apoptotic and antiproliferative activities. The extracts were not as effective as doxorubicin; however, the extracts natural composition and ability to reduce weight loss due to cancer indicate potential to be used in combination with or as an alternative to cancer-treating medications. Further research includes that mechanistic studies and clinical trials are needed to confirm their therapeutic potential.

cancer biology↗

bioRxiv2024

Antimicrobial resistance, pathogenicity and virulence patterns of Escherichia coli isolated from cockroaches (Blattella germanica) across diverse environments: a public health concern

This investigation explores the prevalence and antimicrobial resistance (AMR) of Escherichia coli isolated from Blattella germanica (cockroaches) from diverse locations, including homes, kitchens, and laboratories, over the course of six months, from August 2022 to January 2023. A total of 125 cockroaches were analyzed, yielding 67 (53%) of positive E. coli isolates, with kitchen environments having the highest incidence (57.77%). The existence of virulence genes (stx1, stx2, and rfbO157) was confirmed by pathogenicity assessments carried out on mouse model, which led to a considerable increase in morbidity and mortality. 82.08% of isolates showed evidence of resistance to at least one antibiotic, according to the antimicrobial susceptibility test with {beta}-lactams displaying the highest rates of resistance. Remarkably, complex resistance patterns were observed in 77.61% of the isolates, which were categorized as multidrug-resistant. Multiple antibiotic resistance genes (ARGs) were found by molecular analysis, particularly blaTEM and tetA as well as virulence-associated genes (VAGs) linked to extraintestinal pathogenic E. coli. Phylogenetic grouping indicated that 90.38% of the MDR isolates belonged to virulent groups B2 and D. These findings highlight the role of cockroaches as potential reservoirs for pathogenic E. coli, raising significant public health concerns regarding AMR. The study underscores the imperative need for thorough investigation and feasible control strategies to ease the dissemination of AMR in diverse contexts.

microbiology↗

bioRxiv2024

Horizon: CNV interpretation through rapid automated ACMG-aligned pathogenicity analysis

PurposeOur study assesses the Horizon model, a novel CNV classification tool developed in line with American College of Medical Genetics (ACMG) guidelines, to enhance the classification of pathogenicity in CNVs. MethodsHorizon utilizes a ranking-based algorithm, incorporating multiple proprietary databases and variant inheritance models as per ACMG standards. The models effectiveness was verified through Area Under the Curve (AUC) analyses on three datasets comprising 696 pathogenic inherited or de novo variants, as classified by clinical geneticists and several established tools. ResultsHorizon achieved an AUC of 0.97 in the discovery cohort, demonstrating high accuracy in CNV interpretation and proficiency in predicting pathogenicity. We observed an AUC of 0.87 in the de novo variant cohort and an overall AUC of 0.94 across all cohorts, surpassing tools like ClassifyCNV and AnnotSV. It showed particular effectiveness in interpreting duplication CNVs and the highest performance for CNVs sized 3-5 Mb. ConclusionThe Horizon model offers robust and accurate CNV interpretation, outperforming existing tools and aligning closely with clinical evaluations. Its comprehensive approach, integrating a range of genomic features and following ACMG guidelines, makes it a crucial tool in the genomic interpretation landscape, facilitating the rapid and accurate diagnosis of genetic disorders.

genomics↗

bioRxiv2023

Knowledge, attitudes and biosecurity practices among the small-scale dairy farmers in Sylhet District, Bangladesh

BackgroundIn the context of zoonosis, Bangladeshs small-scale dairying is yet to frame satisfactory levels due to poor biosecurity practices. ObjectivesThis study intended to reveal the degree of knowledge, attitudes, and biosecurity practices among Sylhet district, Bangladeshs small-scale dairy farmers. We also focused on the association between biosecurity practices and the incidence of non-specific enteritis in humans. MethodsA questionnaire-based survey was conducted on the farmers KAP via personal interviews of 15 farmers from the randomly selected fifteen small-scale dairy farms. The questionnaire was developed with six questions for knowledge, six questions for attitude, and 12 questions for the practice of biosecurity measures. Alongside that, data on the number of non-specific enteritis cases experienced by the farmers or their family members were also recorded. Spearman correlation was used to find out the correlation among KAP variables and between practice scores and non-specific enteritis incidences. ResultsWe found an insignificant (p > 0.05) influence of demographic characteristics over knowledge, attitude, and biosecurity practices. Significant (p<0.05) and strong correlations were found in knowledge-attitude (r = 0.65), knowledge-practice (r = 0.71), and attitude-practice (r = 0.64). Incidences of non-specific enteritis and biosecurity measures practice were also strongly correlated (r = -0.9232) and statistically significant (p<0.05). ConclusionsOur study suggests that increasing knowledge and developing a good attitude are necessary to increase the adaptation of biosecurity measures as three of these factors are correlated. Also, farm biosecurity measures are closely related to human health.

scientific communication and education↗

bioRxiv2022

Modulation of Arm Swing Frequency and Gait Using Rhythmic Tactile Feedback

Due to the neural coupling between upper and lower limbs and the importance of interlimb coordination in human gait, it has been recommended that focusing on appropriate arm swing should be a part of gait rehabilitation in individuals with walking impairments. Despite its vital importance, there is a lack of effective methods to exploit the potential of arm swing inclusion for gait rehabilitation. In this work, we present a lightweight and wireless haptic feedback system that provides highly synchronized vibrotactile cues to the arms to manipulate arm swing and investigate the effects of this manipulation on the subjects gait in a study with 12 participants (20-44 years). We found the developed system effectively adjusted the subjects arm swing and stride cycle times by significantly reducing and increasing those parameters by up to 20% and 35%, respectively, compared to their baseline values during normal walking with no feedback. Particularly, the reduction of arms and legs cycle times translated into a substantial increase of about 19.3% (on average) in walking speed. The response of the subjects to the feedback was also quantified in both transient and steady-state walking. The analysis of settling times from the transient responses revealed a fast and similar adaptation of both arms and legs movements to the feedback for reducing cycle time (i.e., increasing speed). Conversely, larger settling times and the time differences between arms and legs responses were observed due to feedback for increasing cycle times (i.e., reducing speed). The results clearly demonstrate the potential of the developed system to induce different arm-swing patterns as well as the ability of the proposed method to modulate key gait parameters through capitalizing on the interlimb neural coupling with implications for gait training.

bioengineering↗