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Karambelkar, K. M.

Publications and source records attributed to Karambelkar, K. M..

2 recordsLinked to original sources

STING: A Graph Neural Network Approach for Computational Inference of Spatial Transcriptomic Profiles

Spatial transcriptomics enables the measurement of mRNA counts at spatial locations within a tissue but faces challenges such as high experimental costs, technical expertise requirements, and low RNA detection efficiency at high resolution. We present STING (Spatial Transcriptomics Inference using Graph neural networks), a computational approach that infers spatial gene expression patterns with high efficiency. STING integrates convolutional neural networks (CNNs) pre-trained on histological images with graph neural networks (GNNs) to model spatial proximity, representing tissue sections as nearest-neighbor graphs where spatially adjacent spots are interconnected. We train GNNs on these graphs to predict gene expression at additional tissue locations, including unseen samples. Evaluated on two public spatial transcriptomics datasets (59 and 36 tissues), STING achieves a Pearson correlation coefficient (PCC) of up to 0.79 for super-resolution and 0.69 for tissue-wide inference, outperforming existing methods in accuracy. Our results demonstrate that STING is an effective and computationally efficient tool for predicting spatial gene expression, with significant applications in cancer research, personalized medicine, and beyond.

bioinformatics↗

Neural differential equations enable early-stage prediction of preterm birth using vaginal microbiota

AO_SCPLOWBSTRACTC_SCPLOWPreterm births (PTBs), i.e., births before 37 weeks of gestation are completed, are one of the leading issues concerning infant health, and is a problem that plagues all parts of the world. Millions of infants are born preterm globally each year, resulting in developmental disorders in infants and increase in neonatal mortality. Although there are known risk factors for PTB, the current procedures used to assess PTB risk are effective only at the later stages of pregnancy, which reduces the impact of currently possible interventions administered to prevent PTB or mitigate its ill-effects. Vaginal microbial communities have recently garnered attention in the context of PTB, with the notion that a highly diverse microbiome is detrimental as far as PTB is concerned. Increased abundance or scarcity of certain microbial species belonging to specific genera has also been linked to PTB risk. Consequently, attempts have been made towards establishing a correlation between alpha-diversity indices associated with vaginal microbial communities, and PTB. However, the vaginal microbiome varies greatly from individual to individual, and this variation is more pronounced in racially, ethnically and geographically diverse populations, which diversity indices may not be able to overcome. Machine learning (ML)-based approaches have also previously been explored, however, the success of these approaches reported thus far has been limited. Additionally, microbial communities have been reported to evolve during the duration of the pregnancy, and capturing such a signature may require higher, more complex modeling paradigms. Thus, alternative approaches are necessary to identify signatures in these microbial communities that are capable of distinguishing PTB from a full-term pregnancy. In this study, we have highlighted the limitations of diversity indices for prediction of PTB in racially diverse cohorts. We applied Deep Learning (DL)-based methods to vaginal microbial abundance profiles obtained at various stages of pregnancy, and Neural Controlled Differential Equations (CDEs) are able to identify a signature in the temporally-evolving vaginal microbiome during trimester 2 and can predict incidences of PTB (mean test set ROC-AUC = 0.81, accuracy = 75%, F1-score = 0.71) significantly better than traditional ML classifiers such as Random Forests (mean test set ROC-AUC = 0.65, accuracy = 66%, F1-score = 0.42) and Decision Trees (mean test set ROC-AUC = 0.48, accuracy = 46%, F1-score = 0.40), thus enabling effective early-stage PTB risk assessment. GO_SCPLOWRAPHICALC_SCPLOW AO_SCPLOWBSTRACTC_SCPLOW O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=172 SRC="FIGDIR/small/558954v1_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@3da4e1org.highwire.dtl.DTLVardef@113e22aorg.highwire.dtl.DTLVardef@6552b9org.highwire.dtl.DTLVardef@1a232d_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗