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Kabir, A.

Publications and source records attributed to Kabir, A..

14 recordsLinked to original sources

CMVAE: Contrastive Supervision Improves Single-Omic Latent Manifold for Breast Cancer Survival Prognosis

High-dimensional omics data are vital for fore- casting patient prognosis in oncology. While deep multi-omics learning methods are increasingly popular, they suffer from data missingness and low patient overlap across modalities. Consequently, advancing single-omic representation learning re- mains a critical yet challenging research problem. Standard generative dimensionality reduction methods rely on recon- struction objectives that optimize the global manifold topology; however, overlook downstream clinical outcomes. To address these limitations, we introduce a Contrastive Masked Denois- ing Variational Autoencoder (CMVAE), a self-supervised dual- optimization framework designed to map single-omic information into a clinical outcome-aware latent space. A stochastic feature masking strategy corrupts the input omic profiles, and CMVAE is optimized to simultaneously infer missing molecular data and contrastive alignment of patient survival trajectories. We evaluate CMVAE using leak-proof five-fold stratified cross-validation on the TCGA Breast Invasive Carcinoma (BRCA) cohort. The method outperforms traditional unsupervised methods, achieving an AUROC of 0.7397 {+/-} 0.0239 on patient prognosis. Further analysis demonstrates a highly significant (p < 0.0001) risk stratification among low vs. high risk groups. Beyond comparing within single-omic methods, CMVAE outperforms six state-of- the-art multi-omics survival baselines by a minimum of 3%. Availability: All codes including data preparation scripts, training and validation recipes, and experimental configurations are available at: https://github.com/kabir-ai2bio-lab/CMVAE. Note: Accepted at the IEEE BIBM 2026 workshop RLPD-Bio (Representation Learning and Pattern Discovery for Bioinformatics and Biomedicine).

bioinformatics↗

Rapid chromosomal rearrangements and sex chromosome turnover underlie the evolution of parapatric Pacific Scomber mackerels

Teleost display remarkable species diversity despite relatively conserved karyotypes, suggesting an important role for chromosomal rearrangements in speciation. Yet this hypothesis remains poorly tested in pelagic marine fishes, as genomic studies have predominantly focused on freshwater and coastal taxa. In this study, we investigated the genomic basis of hybrid incompatibility between two parapatric Pacific mackerels, Scomber japonicus and S. australasicus, hypothesizing chromosomal rearrangements as the major driving forces. We generated haplotype-resolved de novo genome assemblies for both Pacific species and assessed genomic rearrangements along with the genome of the Atlantic species, S. scombrus, reconstructed from publicly available data. Comparative genomic analyses revealed extensive chromosomal rearrangements across the genomes. Notably, the rate of chromosomal inversions was approximately sevenfold higher between the two Pacific species than between allopatric lineages. These rearrangements included complex structural changes involving megabase-scale inversions and associated translocations. Our analyses also showed that the sex chromosomes of the three species evolved independently. In the two Pacific species, large recombination-suppression regions (>10 Mb) arose convergently but through distinct mechanisms: tandem chromosomal inversions in S. japonicus and, most likely, transposable element-mediated sequence divergence in S. australasicus. By contrast, recombination suppression in S. scombrus is restricted to a [~]14 kb hemizygous region containing amhr2Y, generated by duplication and translocation. Population-level analyses further revealed ongoing evolution of recombination-suppressed regions in the Pacific species and uncovered multiple Y chromosome lineages in S. australasicus that differ markedly in the extent of recombination suppression. Together, these results demonstrate rapid structural genome evolution in Scomber and provide a genomic framework for understanding how chromosomal rearrangements contribute to reproductive isolation, sex chromosome turnover, and the diversification of pelagic marine fishes.

evolutionary biology↗

Predicting Obstetric and Non-obstetric Diagnoses Co-occurrences during Pregnancy

Pregnancy care often involves simultaneous obstetric and other medical conditions, but their co-occurrence patterns are rarely modeled explicitly in a systematic, network-based approach. In this work, we formulate obstetric and non-obstetric diagnoses co-occurrences as a link prediction problem on a diagnosis-level homogeneous graph constructed from pregnancy encounters. Diagnoses are represented as nodes connected by co-occurrence edges, with node features capturing graph structure and demographic statistics3. We address this challenge by leveraging collected electronic health records data and study several standalone and hybrid graph neural network (GNN) architectures, including GCN, GAT, GraphSAGE, and three hybrid encoders that combine complementary aggregation mechanisms, namely GCN+GraphSAGE, GCN+GAT, and GAT+GraphSAGE. All models used consistent train-validation-test splits and are evaluated on 5- fold cross-validation sets. Among standalone models, GraphSAGE achieved the strongest performance, whereas hybrid GraphSAGE-based models (GCN+GraphSAGE and GAT+GraphSAGE) are best performers. The GCN+GraphSAGE hybrid, reaching an AUROC and AUPRC of approximately 0.90, consistently outperformed all other architectures. Further analysis of top-ranked predicted links revealed clinically plausible associations between pregnancy stage and risk-related diagnoses and common endocrine, metabolic, and hematological conditions. These findings indicate that graph-based link prediction may effectively prioritize obstetric and non-obstetric diagnosis pairs, providing a scalable framework for identifying clinically meaningful comorbidity patterns. They may further support hypothesis generation and downstream obstetric risk stratification efforts. AvailabilityAll codes including data preparation scripts, training and validation recipes, and experimental configurations are available at: https://github.com/kabir-ai2bio-lab/ob-nonob-diagnoses-cooccurrences.

bioinformatics↗

LoMuS: Low-Rank Adaptation with Multimodal Representations Improves Protein Stability Prediction

Protein folding stability is a key determinant for understanding protein dynamics, including molecular function, pathogenicity, and/or protein engineering. Yet, accurate prediction of protein stability changes remains a challenging problem due to the high-variability in the available data, especially from sequence-only information when structural knowledge is of low-resolution or unavailable. In this work, we introduce LoMuS, a Multimodal deep learning model that combines two complimentary aspects of the molecule and predicts unnormalized protein Stability effect from the primary sequence as input. In the core of the model architecture, a fusion network integrates explicit physicochemical descriptors with Low-rank adapted protein language model derived embeddings from the sequence that shows powerful and accurate generalization ability across various benchmark settings for predicting protein folding stability changes. We compared and rigorously evaluated our model capacity spanning from fold-induced stability changes to mutation caused stability effect prediction. This includes benchmarking against various held-out protein domains, out-of-distribution label settings and per-protein evaluation. LoMuS consistently outperforms other sequence-only protein stability baselines. It achieves an absolute performance gain by an at least 10% in the spearman rank correlation metric for predicting protein stability across many held-out domains and out-of-distribution stability label predictions. Per-protein validation additionally demonstrates promising performance gain of our model. Ablation analysis on the model architectural choices confirms that complementary signals from derived features are critical for this multimodal approach. We believe LoMuS advances protein engineering research and can aid in rational protein design by elucidating precise protein stability changes. AvailabilityAll codes including data preparation scripts, training and validation recipes, and experimental configurations for LoMuS are available at: https://github.com/samuelinfantee/LoMuS-repository. Supplementary informationSupplementary data are available at Journal Name online.

bioinformatics↗

In Silico Evaluation and Therapeutic Targeting of LVDD9B Protein for WSSV Inhibition: Molecular and Ecological Insights for Aquaculture Solutions

BackgroundThis study aimed to investigate structural dynamics, binding interactions, stability, pharmacokinetics, ecological risks, and bioactivity of shrimp receptor protein LVDD9B to identify potential therapeutic candidates against White Spot Syndrome Virus (WSSV). MethodsLVDD9B proteins 3D structure was predicted using SWISS-MODEL and validated with ProSA and Ramachandran plots. Protein-protein docking between LVDD9B and VP26 (WSSV protein) was performed using HADDOCK 2.4 server. Molecular docking, dynamics simulations, binding-free energy calculations, principal component analysis (PCA), electrostatic, and vibrational frequency analyses evaluated binding affinity, stability and polarity of complexes. Results128-amino-acids of LVDD9B protein was predicted as predominantly cytoplasmic with stable, and hydrophilic, with structural analysis identified key secondary structures and conserved chitin-binding site. Docking studies revealed strong interactions between LVDD9B and VP26, supported by hydrogen-bonds and salt bridges. Molecular dynamics simulations demonstrated stable complexes with fluctuating RMSD values, and MM/GBSA calculations indicated favorable binding free energies. Pharmacokinetic analysis highlighted promising bioavailability and drug-like properties for Luteolin and Quercetin from Cuscuta reflexa, while ecological assessment identified Cosmosiin as least hazardous, with Quercetin and Luteolin showing higher toxicity. PCA revealed stable protein-ligand complexes with flexibility in Apo form. Isorhoifolin exhibited the lowest internal energy (-2099.4722 Hartree) and highest dipole moment (8.1833 Debye). Frontier orbital analysis showed HOMO-LUMO gaps (4.05-4.34 eV) influencing reactivity, while MEP and vibrational frequency analyses supported compound stability and bioactivity. ConclusionsThis study explores LVDD9Bs structural and interaction dynamics for developing antiviral therapy against WSSV, highlighting therapeutic potential of Cosmosiin, Isorhoifolin, Quercetin and Luteolin based on their pharmacokinetic and ecological profiles.

bioinformatics↗

Differential control of growth and identity by HNF4α isoforms in pancreatic ductal adenocarcinoma

BackgroundAlthough transcriptomic studies have stratified pancreatic ductal adenocarcinoma (PDAC) into clinically relevant subtypes, classical or basal-like, further research is needed to identify the transcriptional regulators of each subtype. Previous studies identified HNF4 as a key regulator of the classical subtype, but the distinct contributions of its isoforms (P1 and P2), which display dichotomous functions in normal development and gastrointestinal malignancies, remain unexplored. ObjectiveThe objective of this study is to investigate the role of HNF4 P1 and P2 isoforms in regulating growth and differentiation. DesignWe performed functional, transcriptomic, and epigenetic analysis after exogenous expression in HNF4-negative models or CRISPRi-mediated knockdown of endogenous isoforms. ResultsWe characterized the variable expression of P1 isoforms in HNF4-positive tumors. We demonstrate that P1 isoforms are less compatible with growth than P2 isoforms. Despite sharing a common DNA binding domain, we show that P1 isoforms are stronger transcriptional regulators. ConclusionsOur study characterizes the functional roles of HNF4 P1 and P2 isoforms in PDAC and highlights the necessity of considering different isoforms when studying molecular regulators.

cancer biology↗

Efficient High-Throughput DNA Breathing Features Generation Using Jax-EPBD

DNA breathing dynamics--transient base-pair opening and closing due to thermal fluctuations--are vital for processes like transcription, replication, and repair. Traditional models, such as the Extended Peyrard-Bishop-Dauxois (EPBD), provide insights into these dynamics but are computationally limited for long sequences. We present JAX-EPBD, a high-throughput Langevin molecular dynamics framework leveraging JAX for GPU-accelerated simulations, achieving up to 30x speedup and superior scalability compared to the original C-based EPBD implementation. JAX-EPBD efficiently captures time-dependent behaviors, including bubble lifetimes and base flipping kinetics, enabling genome-scale analyses. Applying it to transcription factor (TF) binding affinity prediction using SELEX datasets, we observed consistent improvements in R2 values when incorporating breathing features with sequence data. Validating on the 77-bp AAV P5 promoter, JAX-EPBD revealed sequence-specific differences in bubble dynamics correlating with transcriptional activity. These findings establish JAX-EPBD as a powerful and scalable tool for understanding DNA breathing dynamics and their role in gene regulation and transcription factor binding.

bioinformatics↗

Scalable DNA Feature Generation and Transcription Factor Binding Prediction via Deep Surrogate Models

Simulating DNA breathing dynamics, for instance Extended Peyrard-Bishop-Dauxois (EPBD) model, across the entire human genome using traditional biophysical methods like pyDNA-EPBD is computationally prohibitive due to intensive techniques such as Markov Chain Monte Carlo (MCMC) and Langevin dynamics. To overcome this limitation, we propose a deep surrogate generative model utilizing a conditional Denoising Diffusion Probabilistic Model (DDPM) trained on DNA sequence-EPBD feature pairs. This surrogate model efficiently generates high-fidelity DNA breathing features conditioned on DNA sequences, reducing computational time from months to hours-a speedup of over 1000 times. By integrating these features into the EPBDxDNABERT-2 model, we enhance the accuracy of transcription factor (TF) binding site predictions. Experiments demonstrate that the surrogate-generated features perform comparably to those obtained from the original EPBD framework, validating the models efficacy and fidelity. This advancement enables real-time, genome-wide analyses, significantly accelerating genomic research and offering powerful tools for disease understanding and therapeutic development.

genomics↗

Advancing Transcription Factor Binding Site Prediction Using DNA Breathing Dynamics and Sequence Transformers via Cross Attention

Understanding the impact of genomic variants on transcription factor binding and gene regulation remains a key area of research, with implications for unraveling the complex mechanisms underlying various functional effects. Our study delves into the role of DNAs biophysical properties, including thermodynamic stability, shape, and flexibility in transcription factor (TF) binding. We developed a multi-modal deep learning model integrating these properties with DNA sequence data. Trained on ChIP-Seq (chromatin immunoprecipitation sequencing) data in vivo involving 690 TF-DNA binding events in human genome, our model significantly improves prediction performance in over 660 binding events, with up to 9.6% increase in AUROC metric compared to the baseline model when using no DNA biophysical properties explicitly. Further, we expanded our analysis to in vitro high-throughput Systematic Evolution of Ligands by Exponential enrichment (SELEX) and Protein Binding Microarray (PBM) datasets, comparing our model with established frameworks. The inclusion of DNA breathing features consistently improved TF binding predictions across different cell lines in these datasets. Notably, for complex ChIP-Seq datasets, integrating DNABERT2 with a cross-attention mechanism provided greater predictive capabilities and insights into the mechanisms of disease-related non-coding variants found in genome-wide association studies. This work highlights the importance of DNA biophysical characteristics in TF binding and the effectiveness of multi-modal deep learning models in gene regulation studies.

bioinformatics↗

Examining DNA Breathing with pyDNA-EPBD

MotivationThe two strands of the DNA double helix locally and spontaneously separate and recombine in living cells due to the inherent thermal DNA motion.This dynamics results in transient openings in the double helix and is referred to as "DNA breathing" or "DNA bubbles." The propensity to form local transient openings is important in a wide range of biological processes, such as transcription, replication, and transcription factors binding. However, the modeling and computer simulation of these phenomena, have remained a challenge due to the complex interplay of numerous factors, such as, temperature, salt content, DNA sequence, hydrogen bonding, base stacking, and others. ResultsWe present pyDNA-EPBD, a parallel software implementation of the Extended Peyrard-Bishop-Dauxois (EPBD) nonlinear DNA model that allows us to describe some features of DNA dynamics in detail. The pyDNA-EPBD generates genomic scale profiles of average base-pair openings, base flipping probability,DNA bubble probability, and calculations of the characteristically dynamic length indicating the number of base pairs statistically significantly affected by a single point mutation using the Markov Chain Monte Carlo (MCMC) algorithm.

genomics↗

Genomic diversity of Streptococcus uberis isolated from clinical mastitis of cattle in selected areas of Bangladesh

Streptococci are the major etiology in mastitis, a cause of huge economic losses in the dairy industries. Streptococcus (S.) agalactiae, S. dysagalactiae and S. uberis are mostly encountered in bovine mastitis; however, data on the diversity and characteristics of Streptococcus in clinical mastitis of cattle in Bangladesh is lacking. Thus, the present study was aimed to determine the diversity and antimicrobial resistance pattern of Streptococcus spp. isolated from clinical mastitis of cattle reared in Bangladesh. A total of 105 milk samples comprising eighty (80) from cattle with clinical mastitis (CCM) and twenty-five (25) from apparently healthy cattle (AHC) in four prominent dairy farms and one dairy community were purposively collected and examined in this study. Milk samples were enriched in Luria Bertani broth (LB) and Streptococcus spp. was isolated on Modified Edwards Medium and identified by 16S rRNA gene sequencing. Among eighty (80) clinical samples, eighteen (18) were positive for Streptococcus spp. while none of the milk from AHC revealed Streptococcus by cultural and molecular examination. Sequencing and phylogenetic analysis identified 55.6%, 33.3%, 5.6% and 5.6% of the Streptococcus isolates as S. uberis, S. agalactiae, S. hyovaginalis and S. urinalis, respectively. Antibiotic sensitivity testing with antimicrobials commonly used to treat clinical mastitis revealed 100%, 100%, and 30% of the S. agalactiae, S. hyovaginalis, and S. uberis as multidrug-resistant, respectively. Molecular characterization through whole genome sequencing of five (5) S. uberis isolates identified at least two novel ST types of S. uberis circulating in the study areas with one ST (4/5 isolates) clustered with the isolates from China, India and Thailand, and the other (1/5) with UK, Ireland and Australia. Pan-genome analysis and phylogeny of the core genome sequences also clustered the isolates into two sub-clusters, indicating the presence of at least two different subtypes of S. uberis in the study area. On virulence profiling, all the isolates of this study were found to harbor at least 35 virulence and putative virulence genes probably associated with intramammary infection (IMI) indicating all the S. uberis isolated in this study as potential pathogen. From the overall findings it was evident that Strepococcus occurring in bovine mastitis are diverse and S. uberis genome carries an array of putative virulence factors which need to be investigated genotypically and phenotypically to identify a specific trait or determinant governing the virulence and fitness of this bacterium. Moreover, Streptococcus isolated in this study carried multidrug resistance which needs careful consideration during the selection of a treatment regimen for mastitis.

microbiology↗

GOProFormer: A Multi-modal Transformer Method for Gene Ontology Protein Function Prediction

Protein Language Models (PLMs) are shown capable of learning sequence representations useful for various prediction tasks, from subcellular localization, evolutionary relationships, family membership, and more. They have yet to be demonstrated useful for protein function prediction. In particular, the problem of automatic annotation of proteins under the Gene Ontology (GO) framework remains open. This paper makes two key contributions. It debuts a novel method that leverages the transformer architecture in two ways. A sequence transformer encodes protein sequences in a task-agnostic feature space. A graph transformer learns a representation of GO terms while respecting their hierarchical relationships. The learned sequence and GO terms representations are combined and utilized for multi-label classification, with the labels corresponding to GO terms. The method is shown superior over recent representative GO prediction methods. The second major contribution in this paper is a deep investigation of different ways of constructing training and testing datasets. The paper shows that existing approaches under- or over-estimate the generalization power of a model. A novel approach is proposed to address these issues, resulting a new benchmark dataset to rigorously evaluate and compare methods and advance the state-of-the-art.

bioinformatics↗

Repeated translocation of a supergene underlying rapid sex chromosome turnover in Takifugu fish

Recent studies have revealed a surprising diversity of sex chromosomes in vertebrates. However, the detailed mechanism of their turnover is still elusive. To understand this process, it is necessary to compare closely related species in terms of sex-determining genes and the chromosomes harboring them. Here, we explored the genus Takifugu, in which one strong candidate sex-determining gene, Amhr2, has been identified. To trace the processes involved in transitions in the sex determination system in this genus, we studied 12 species and found that while the Amhr2 locus likely determines sex in the majority of Takifugu species, three species have acquired sex-determining loci at different chromosomal locations. Nevertheless, the generation of genome assemblies for the three species revealed that they share a portion of the male-specific supergene that contains a candidate sex-determining gene, GsdfY, along with genes that potentially play a role in male fitness. The shared supergene span approximately 100 kb and are flanked by two duplicated regions characterized by CACTA transposable elements. These results suggest that the shared supergene has taken over the role of sex-determining locus from Amhr2 in lineages leading to the three species, and repeated translocations of the supergene underlie the turnover of sex chromosomes in these lineages. These findings highlight the underestimated role of a mobile supergene in the turnover of sex chromosomes in vertebrates. SignificanceAlthough turnover of sex chromosomes is very common in many vertebrate lineages, the transition process is still elusive. We studied the sex-determining region (SDR) of 12 congeneric fish species. We found that while nine species retained their ancestral SDR, three species had acquired derived SDRs. Although the derived SDRs resided in three different chromosomes, they harbored a shared supergene flanked by two putative transposable elements. The results highlight the underestimated role of a mobile supergene in turnover of sex chromosomes in vertebrates.

genomics↗

Post-intervention Epidemiology of STH in Bangladesh: data to sustain the gains

IntroductionIn 2008, Bangladesh initiated Preventive Chemotherapy (PCT) for school-age children (SAC) through bi-annual school-based mass drug administration (MDA) to control Soil-Transmitted Helminth (STH) infections. In 2016, the Ministry of Health and Family Welfares Program on Lymphatic Filariasis Elimination and STH (ELFSTH) initiated district-level community impact assessments with Children Without Worms (CWW) using standardized, population-based sampling to measure the post-intervention STH burden across all ages ([&ge;] 1 yr) for the three STH species. Methods & Principal FindingsThe Integrated Community-based Survey for Program Monitoring (ICSPM) was developed by CWW and was used to survey 12 districts in Bangladesh from 2017 - 2020. We combined the individual demographic and parasite-specific characteristics from 10 districts and linked them with the laboratory data for collective analysis. Our analysis identified district-specific epidemiologic findings, important for program decisions. Of the 17,874 enrolled individuals, 10,824 (61%) provided stool samples. Overall, the prevalence of any STH species was substantially reduced to 14% from 79.8% in 2005. The impact was similar across all ages. STH prevalence was below 10% in 10 districts collectively, but remained high in 4 districts, despite their high reported PCT coverage in previous years. Among all, Bhola district was unique because it was the only district with high Trichuris prevalence. ConclusionBangladesh successfully lowered STH prevalence across all ages despite targeting SAC only. Data from the survey indicate significant number of adults and pre-school age children (PSAC) were self-deworming with purchased pills. This may account for the flat impact curve across all ages. Overall prevalence varied across surveyed districts, with persistent high transmission in the northeastern districts and a district in the central flood zone, indicating possible service and ecological factors. Discrepancies in the impact between districts highlight the need for district-level data to evaluate program implementation after consistent high PCT coverage. Authors SummaryBangladesh government conducted school-based mass drug administration (MDA) for over 10 years to control soil-transmitted helminth (STH) infections. School-based evaluations of MDA indicate a reduction in STH burden among school-aged children (SAC). To further assess the impact on the community, Children Without Worms and the Ministry of Health and Family Welfares Program on Lymphatic Filariasis Elimination and STH (ELFSTH) initiated district-level community impact surveys in 12 districts. We share the results from the latter 10 districts here. Our analysis of 10,824 interviews and stool samples from 10 districts showed an estimated 14% of community members infected with at least one species of STH. This finding is substantially lower than the baseline STH prevalence (79.8%) estimated in 2005. Bangladeshs successful impact was achieved across all ages despite only treating SAC. Deworming source data showed significant numbers of adults and pre-school age children (PSAC) self-dewormed with locally purchased pills. Prevalence varied across the surveyed districts, with persistent high transmission in the northeastern districts and a district in the central flood zone, indicating possible ecological and service factors contributing to persistent infections. Discrepancies in the impact across districts highlights the need for sub-national level data to evaluate program performance fllowing consistent high intervention.

scientific communication and education↗