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Ali, H.

Publications and source records attributed to Ali, H..

At least 37 records · Page 2Linked to original sources

State-transition Modeling of Blood Transcriptome Predicts Disease Evolution and Treatment Response in Chronic Myeloid Leukemia (CML)

Chronic myeloid leukemia (CML) is initiated and maintained by BCR::ABL which is clinically targeted using tyrosine kinase inhibitors (TKIs). TKIs can induce long-term remission but are also not curative. Thus, CML is an ideal system to test our hypothesis that transcriptome-based state-transition models accurately predict cancer evolution and treatment response. We collected time-sequential blood samples from tetracycline-off (Tet-Off) BCR::ABL-inducible transgenic mice and wild-type controls. From the transcriptome, we constructed a CML statespace and a three-well leukemogenic potential landscape. The potentials stable critical points defined observable disease states. Early states were characterized by anti-CML genes opposing leukemia; late states were characterized by pro-CML genes. Genes with expression patterns shaped similarly to the potential landscape were identified as drivers of disease transition. Re-introduction of tetracycline to silence the BCR::ABL gene returned diseased mice transcriptomes to a near healthy state, without reaching it, suggesting parts of the transition are irreversible. TKI only reverted the transcriptome to an intermediate disease state, without approaching a state of health; disease relapse occurred soon after treatment. Using only the earliest time-point as initial conditions, our state-transition models accurately predicted both disease progression and treatment response, supporting this as a potentially valuable approach to time clinical intervention even before phenotypic changes become detectable.

cancer biology↗

A Novel Computational Approach for the Mining of Signature Pathways Using Species Co-occurrence Networks in Gut Microbiomes

Advances in metagenome sequencing data continue to enable new methods for analyzing biological systems. When handling microbial profile data, metagenome sequencing has proven to be far more comprehensive than traditional methods such as 16s rRNA data, which rely on partial sequences. Microbial community profiling can be used to obtain key biological signals that pave the way for better and accurate understanding of complex systems that are critical for advancing biomedical research and healthcare. There have been few attempts to uncover microbial community associations with certain health conditions. However, such attempts have mostly used partial or incomplete data to accurately capture those associations. This study introduces a novel computational approach for the identification of co-occurring microbial communities using the abundance and functional roles of species-level microbiome data. The proposed approach is then used to identify signature pathways associated with inflammatory bowel disease (IBD). Furthermore, we developed a computational pipeline to identify microbial species co-occurrences from metagenome data. When comparing IBD to a control group, we show that co-occurring communities of species are enriched for potential pathways. We also show that the identified co-occurring microbial species operate as a community to facilitate pathway enrichment. The obtained findings suggest that the proposed network model, along with the computational pipeline, provide a valuable analytical tool to analyze complex biological systems and extract pathway signatures that classify or diagnose certain health conditions. CCS CONCEPTS* Applied computing [->] Biological networks; Bioinformatics; Systems biology. ACM Reference FormatSuyeon Kim, Ishwor Thapa, and Hesham Ali. 2023. A Novel Computational Approach for the Mining of Signature Pathways Using Species Co-occurrence Networks in Gut Microbiomes. In Proceedings of ACM Conference (Conference17). ACM, New York, NY, USA, 10 pages. https://doi.org/10.1145/nnnnnnn.nnnnnnn

bioinformatics↗

Exploring Microbial Diversity and Functional Potential along the Bay of Bengal Coastline in Bangladesh: Insights from Amplicon Sequencing and Shotgun Metagenomics

Although the Bay of Bengal (BoB) is the worlds largest bay, possessing distinct physiochemical properties, it has garnered little research focus concerning its microbial diversity and ecological importance. Here, we present amplicon (16S and 18S) profiling and shotgun metagenomics data regarding microbial communities from BoBs eastern coast, viz., Saint Martin and Coxs Bazar, Bangladesh. From the 16S sequencing data, Proteobacteria appeared to be the dominant phylum in both locations, with Alteromonas, Methylophaga, Anaerospora, Marivita, and Vibrio dominating in Coxs Bazar and Pseudoalteromonas, Nautella, Marinomonas, Vibrio, and Alteromonas dominating the Saint Martin site. From the 18S sequencing data, Ochrophyta, Chlorophyta, and Protalveolata appeared among the most abundant eukaryotic divisions in both locations, with significantly higher abundance of Choanoflagellida, Florideophycidae, and Dinoflagellata in Coxs Bazar. Functional annotations revealed that the microbial communities in these samples harbor genes for biofilm formation, quorum sensing, xenobiotics degradation, antimicrobial resistance, and a variety of other processes. Together, these results provide the first molecular insight into the functional and phylogenetic diversity of microbes along the BoB coast of Bangladesh and lay the foundation for further in-depth assessment of microbial community dynamics and functional potential in the context of global change in this region.

microbiology↗

Spatial proteomics of human diabetic kidney disease, from health to class III

Aims/HypothesisDiabetic kidney disease (DKD) remains a significant cause of morbidity and mortality in people with diabetes. Though animal models have taught us much about the molecular mechanisms of DKD, translating these findings to human disease requires greater knowledge of the molecular changes caused by diabetes in human kidneys. Establishing this knowledge base requires building carefully curated, reliable, and complete repositories of human kidney tissue, as well as tissue proteomics platforms capable of simultaneous, spatially resolved examination of multiple proteins. MethodsWe used the multiplexed immunofluorescence platform CO-Detection by indexing (CODEX) to image and analyze the expression of 21 proteins in 23 tissue sections from 12 individuals with diabetes and healthy kidneys (DM, 5 individuals), DKD classes IIA, and IIB (2 individuals per class), IIA-B intermediate (2 individuals), and III (one individual). ResultsAnalysis of the 21-plex immunofluorescence images revealed 18 cellular clusters, corresponding to 10 known kidney compartments and cell types, including proximal tubules, distal nephron, podocytes, glomerular endothelial and peritubular capillaries, blood vessels, including endothelial cells and vascular smooth muscle cells, macrophages, cells of the myeloid lineage, broad CD45+ inflammatory cells and the basement membrane. DKD progression was associated with co-localized increase in collagen IV deposition and infiltration of inflammatory cells, as well as loss of native proteins of each nephron segment at variable rates. Compartment-specific cellular changes corroborated this general theme, with compartment-specific variations. Cell type frequency and cell-to-cell adjacency highlighted (statistically) significant increase in inflammatory cells and their adjacency to tubular and SMA+ cells in DKD kidneys. Finally, DKD progression was marked by substantial regional variability within single tissue sections, as well as variability across patients within the same DKD class. The sizable intra-personal variability in DKD severity impacts pathologic classifications, and the attendant clinical decisions, which are usually based on small tissue biopsies. Conclusions/InterpretationsHigh-plex immunofluorescence images revealed changes in protein expression corresponding to differences in cellular phenotypic composition and microenvironment structure with DKD progression. This initial dataset demonstrates the combined power of curated human kidney tissues, multiplexed immunofluorescence and powerful analysis tools in revealing pathophysiology of human DKD.

molecular biology↗

Perception and Readiness Towards Inter-Professional Education Among Different Health Care Disciplines at Khyber Medical University Peshawar

Interprofessional learning (IPL) is an approach that teaches students diverse disciplines to communicate with each other about their professional knowledge in order to acquire a more complex one understanding of the current situation. According to WHO definition of IPE "its a process between two or more professionals learn about from, and with one another to permit effective association and enhance health outcome. The aim of this study was to measure perception and readiness towards IPE among different health care disciplines. A cross-sectional study was done with two hundred and eighteen post graduate Nursing, public health, physiotherapy, and basic medical sciences students from September,2020 to January,2021 at Khyber Medical University Peshawar Pakistan. Convenient sampling technique was used to collect data. The Readiness for Inter-Professional Learning Scale (RIPLS) and Interdisciplinary Education Perception Scale (IEPS) were used to measure the readiness and perception of students regarding inter-professional leaning. The data were analyzed using software Statistical Package for Social Science (SPSS) (Version 23). The RIPLS was completed by a total of 218 participants (response rate 100%, 61 Nursing students 28%, 51 physiotherapy students 23.4%, 53 public health students 24.3%, and 53 basic medical sciences students 24.3%). As shown in Table 1.1, the majority of respondents were male (51.4%) followed by female (48.6%). Most of the respondents were aged with a mean score of 27.92 {+/-} 3.195. Moreover, majority of respondents have experience less than 5years (75.2%) and (22.8%) has experience above than 5years. Value of perception and readiness in Shapiro-Wilk is .000 which shows that the data variable is not normally distributed. correlation of students towards interprofessional learning by applying Spearman rho test. Students perception has strong positive correlation with their readiness, p value (.000). Also students readiness has strong positive correlation with their perception towards interprofessional learning. This study was to explore the readiness and perception of students towards interprofessional education in different health care students. IPL is beneficial for students to know other professionals to work together for teamwork and collaboration and it also increase communication between different health care professional and patients.

scientific communication and education↗

Design And Optimization Studies Of Tablet In Tablet Formulation Of Diclofenac And Misoprostol: Application Of Response Surface Methodolgy And Compressional Behaviour Strategy

The present study was aimed to develop compression coated tablets of diclofenac sodium (75mg) in the inner core and misoprostol (200 mg) as the outer shell for the effective treatment of rheumatoid arthritis as this dosing frequency is not available in the market yet. Diclofenac sodium inner tablet was manufactured by wet granulation and its enteric coating was applied by Eudragit L 100-55, Isopropyl Alcohol and Opadry II Blue 85 F205034. While immediate-release misoprostol outer shell was also manufactured by wet granulation and coated by Opadry white and Polyethylene glycol 6000. Design of experiment(R) software was used for formulation design and optimization. Quality attributes such as tablet weight, hardness, disintegration time, percent drug dissolution and assay were performed as per official methods and satisfactory results were reported. Physical and chemical stability of selected formulations was evaluated following the ICH guidelines for accelerated stability testing. The compressional analysis of optimized formulation was performed to check the optimum compression pressure to obtain a stable formulation. Based on satisfactory quality attributes; formulation DF9MF7 was successfully developed as compression coated tablet with calculated shelf life of 4.8years. Compression coated tablets comprising of enteric coated diclofenac sodium as inner core and misoprostol as outer shell were successfully developed by wet granulation.

pharmacology and toxicology↗

Attenuation hotspots in neurotropic human astroviruses

During the last decade, the detection of neurotropic astroviruses has increased dramatically. The MLB genogroup of astroviruses represents a genetically distinct group of zoonotic astroviruses associated with gastroenteritis and severe neurological complications in young children, the immunocompromised and the elderly. Using different virus evolution approaches, we identified dispensable regions in the 3' end of the capsid-coding region responsible for attenuation of MLB astroviruses in susceptible cell lines. To create recombinant viruses with identified deletions, MLB reverse genetics and replicon systems were developed. Recombinant truncated MLB viruses had wild type-like or enhanced growth and replication properties in permissive cells but were strongly attenuated in iPSC-derived neuronal cultures confirming the location of neurotropism determinants. This approach can be used for the development of vaccine candidates using attenuated astroviruses that infect humans, livestock animals and poultry.

microbiology↗

Functional Neuroligin-2-MDGA1 interactions differentially regulate synaptic GABAARs and cytosolic gephyrin aggregation

AO_SCPLOWBSTRACTC_SCPLOWThe function of GABAergic synapses is critically shaped by cell adhesion proteins that recruit GABAARs to synapses and mediate transsynaptic signalling, but the synapse-type-specific function of such synaptic adhesion proteins and their mutual interaction remain incompletely understood. A ubiquitous cell adhesion protein at GABAergic synapses is Neuroligin-2 (Nlgn2), which recruits synaptic GABAARs by promoting the assembly of the postsynaptic gephyrin scaffold. While Nlgn2 is present at virtually all GABAergic synapses throughout the forebrain, its loss affects different GABAergic synapse subtypes with different severity, indicating that synapse-specific interactors and synapse-organizer-redundancies define the function of Nlgn2 for a given synapse type. Here we investigated how Nlgn2 function at GABAergic synapses in mouse hippocampal area CA1 is modulated by two recently identified interaction partners, MDGA1 and MDGA2. We show that Nlgn2 and MDGA1 colocalize most prominently in the stratum radiatum (S.R.) of area CA1, and that combined Nlgn2 and MDGA1 deletion causes a layer-specific exacerbation of the loss of gephyrin puncta in layer S.R. seen following Nlgn2 deletion. Intriguingly, combined Nlgn2 and MDGA1 deletion concurrently ameliorates the abnormal cytosolic gephyrin aggregation, the reduction in inhibitory synaptic transmission and the exacerbated anxiety-related behavior seen in Nlgn2 knockout (KO) mice. In contrast, heterozygous deletion of MDGA2 in Nlgn2 KO mice has only minor effects on gephyrin and GABAAR puncta and does not normalize cytosolic gephyrin aggregates, inhibitory synaptic transmission or anxiety-related behavior. Our data indicate that MDGA1, but not MDGA2, modulates Nlgn2 function, primarily by regulating the formation of cytosolic gephyrin aggregates. Given that both Nlgn2 and the MDGA family of proteins have been linked to psychiatric disorders, such as autism and schizophrenia, our data lead to the notion that abnormal gephyrin aggregation may contribute to the pathophysiology of these disorders, and that intervention with gephyrin aggregation could present a novel therapeutic strategy.

neuroscience↗

Taxanes act as vascular disrupting agents and increase rate of metastasis when combined with anti-angiogenic therapy

Taxanes are known to have a profound effect on endothelial cells and the vasculature even at low doses. Here, we show that taxanes, rather than being anti-angiogenic, function more as vascular disrupting agents (VDAs), although they exert a different mechanism of vascular permeabilization when compared to traditional VDAs such as combretastatins. In the tumor context, this VDA-effect leads to a rapid vascular collapse and acute hypoxia. Concomitant treatment with anti-VEGF drugs aggravates hypoxia by blocking vasculogenic rescue mechanisms. While this results in a strong growth-suppressing effect on the tumor, it also increases its invasiveness and metastatic potential. We demonstrate that combination of anti-angiogenic drugs with taxanes blocks tumor reperfusion, intensifies intravasation of circulating tumor cells (CTCs) and strongly increases metastasis. Anti-VEGF drugs are commonly applied in combination with cytotoxic drugs including taxanes. Our findings have significant implications for the clinical use of this drug combination.

cancer biology↗

The wheat head blight pathogen Fusarium graminearum recruits facultative endohyphal bacteria from the soil, making the fungal-bacterial holobiont nitrogen-fixing and increasing the fungal pathogenicity

In nature, fungal endophytes often have facultative endohyphal bacteria. Can a fungal pathogen such as Fusarium graminearum, pathogenic on wheat, get facultative endohyphal bacteria from soil (FEB) and how does the FEB affect the fungal phenotype? We constructed a growth system/microcosm that allowed a molecularly well-studied F. graminearum isolate, PH-1, to grow through natural soil and then be re-isolated on a gentamicin-containing medium, allowing endohyphal growth of the bacteria while killing eventual bacteria growing on the agar medium. We had labelled the F. graminearum PH-1 with a His1mCherry gene staining the fungal nuclei fluorescent red to confirm re-isolation of the same isolate we sent through the soil. Through qPCR of the 16SrRNA gene in the bacteria using universal primers combined with qPCR of the mCherry gene of DNA from the re-isolated cultures of the Fg-FEB holobionts growing on gentamicin-containing media, it was found that most of the holobiont isolates contained about 10 16SrRNA genes per fungal mCherry gene. The Fg-FEB holobiont isolates were sub-cultured several times, and the FEB content on lab media was stable. Sequencing the 16SrRNA gene from several Fg-FEB holobiont isolates revealed known endophytic bacteria capable of nitrogen fixation. We compared the pathogenicity of one of the Fg-FEB holobionts Fg-S.maltophilia, with the background without FEB and found that it was more pathogenic than without FEB. We could also show that the bacterial 16SrRNA load per fungal His1mCherry gene inside the wheat stayed the same as in culture. Finally, we tested if the Fg-S.maltophilia was capable of nitrogen fixation and could show that it, on a nitrogen-free medium, formed a dense mycelium containing proteins at similar levels as on regular nitrogen-containing media. Our results could indicate that naturally occurring fungal pathogens outside lab conditions might contain facultative endohyphal bacteria, positively affecting their pathogenicity and ecological fitness.

ecology↗

MoIsw2 activity could be the missing link between adaptation and mutation instrumental for natural adaptation-directed fast evolution (NADFE) of Magnaporthe oryzae

Isw2 proteins are conserved in eukaryotes and are known to bind to DNA and dynamically influence local chromosome condensation close to their DNA binding site in an ATP-dependent manner making genes close to the binding sites more accessible for transcription and repression. A putative MoISW2 gene was deleted with large effects on plant pathogenicity as a result. The gene was complemented and a ChIP-sec was performed to identify binding sites. RNAsec showed effects on the overall regulation of genes along the chromosomes for mutant and background strains and this was compared with RNAseq from 55 downloaded RNA-seq datasets from the same strain and found similar. MoIsw2 binding and activities create genomic regions affected by MoIsw2 with high gene expression variability close to the MoIsw2 binding sites while surrounding regions have lower gene expression variability. The genes affected by the MoIsw2 activity are niche-determinant genes (secreted proteins, secondary metabolites and stress-coping genes) and avirulence genes. We further show that MoIsw2 binding sites with the DNA binding motifs coincide with known transposable elements (TE) making it likely that TE-transposition at the binding sites can affect the transcription profile of M. oryze in a strain-specific manner. We conclude that MoIsw2 is a likely candidate for a master regulator, regulating the dynamic balance between biomass growth genes (like housekeeping genes) and nich-determinant genes important for ecological fitness. Stress-induced TE transposition is together with MoIsw2 activity a likely mechanism creating more mutations and faster evolution of the niche-determinant genes than for housekeeping genes.

evolutionary biology↗

STING1 activation in brain endothelium by Plasmodium-sequestered heme leads to lethal cerebral malaria through activation of type I IFN response.

Cerebral malaria (CM) is a life-threatening form of Plasmodium falciparum infection caused by brain inflammation. Brain endothelium dysfunction is a hallmark of CM pathology, which is also associated with the activation of the type I interferon (IFN) inflammatory pathway. The molecular triggers and sensors eliciting brain type I IFN cellular responses during CM remain largely unknown. We herein identified the stimulator of interferon response cGAMP interactor 1 (STING1) as the key innate immune sensor that induces Ifn{beta}1 transcription in the brain of mice infected with Plasmodium berghei (Pba). This STING1/IFN{beta}-mediated response increases brain CXCL10 governing the extent of brain leucocyte infiltration and blood-brain barrier (BBB) breakdown, and determining CM lethality. The critical role of brain endothelial cells (BECs) in fueling type I IFN-driven brain inflammation was demonstrated in brain endothelial-specific IFN{beta}-reporter and STING1-deficient Pba-infected mice, which are significantly protected from CM lethality. Moreover, extracellular particles (EPs) released from Pba-infected erythrocytes activated STING1-dependent type I IFN response in BECs, a response requiring intracellular acidification. Fractionation of the EPs enabled us to identify a defined fraction carrying hemoglobin degradation remnants that activates STING1/IFN{beta} in the brain endothelium, a process correlated with heme content. Notably, stimulation of STING1-deficient BECs with heme, docking experiments and in vitro binding assays unveiled that heme is a putative STING1 ligand. This work shows that heme resultant from the parasite heterotrophic activity operates as an alarmin triggering brain endothelial inflammatory responses via STING1/IFN{beta}/CXCL10 axis crucial to CM pathogenesis and lethality. SignificanceCM results from loss of blood-brain endothelial barrier function caused by unrestrained inflammatory response in the natural course of infection by Plasmodium parasites. However, the role of brain endothelium in triggering inflammatory mechanisms is still undetermined. We found that the innate immune sensor STING1 is crucial for production of IFN{beta} in brain endothelial cells in Plasmodium-infected mice. This in turn stimulates CXCL10-mediated recruitment of leukocytes and subsequent brain inflammation and tissue damage. We identified within extracellular particles released from Plasmodium-infected erythrocytes, a fraction containing products of hemoglobin degradation, namely heme, which we show can bind STING1. Our results unravel a new angle of CM pathogenesis: heme contained in particles triggers the STING/IFN{beta}/CXCL10 axis in brain endothelial cells.

immunology↗

SARS-CoV-2 Spike protein activates TMEM16F-mediated platelet pro-coagulant activity

BackgroundThrombosis of the lung micro-vasculature is a characteristic of COVID-19 disease, which is observed in large excess compared to other forms of acute respiratory distress syndrome and thus suggests a trigger for thrombosis endogenous to the lung. Our recent work has shown that the SARS-CoV-2 Spike protein activates the cellular TMEM16F chloride channel and scramblase. Through a screening on >3,000 FDA/EMA approved drugs, we identified Niclosamide and Clofazimine as the most effective molecules at inhibiting this activity. As TMEM16F plays an important role in the stimulation of the pro-coagulant activity of platelets, and considering that platelet abnormalities are common in COVID-19 patients, we investigated whether Spike directly affects platelet activation and pro-thrombotic function and tested the effect of Niclosamide and Clofazimine on these processes. MethodsWe produced SARS-CoV-2 Spike or VSV-G protein-pseudotyped virions, or generated cells expressing Spike on their plasma membrane, and tested their effects on platelet adhesion (fluorescence), aggregation (absorbance), exposure of phosphatidylserine (flow cytometry for annexin V binding), calcium flux (flow cytometry for fluo-4 AM), and clot formation and retraction. These experiments were also conducted in the presence of the TMEM16F activity inhibitors Niclosamide and Clofazimine. ResultsHere we show that exposure to SARS-CoV-2 Spike promotes platelet activation, adhesion and spreading, both when present on the envelope of virions or upon expression on the plasma membrane of cells. Spike was effective both as a sole agonist or by enhancing the effect of known platelet activators, such as collagen and collagen-related peptide. In particular, Spike exerted a noticeable effect on the procoagulant phenotype of platelets, by enhancing calcium flux, phosphatidylserine externalisation, and thrombin generation. Eventually, this resulted in a striking increase in thrombin-induced clot formation and retraction. Both Niclosamide and Clofazimine almost abolished this Spike-induced pro-coagulant response. ConclusionsTogether, these findings provide a pathogenic mechanism to explain thrombosis associated to COVID-19 lung disease, by which Spike present in SARS-CoV-2 virions or exposed on the surface of infected cells, leads to local platelet stimulation and subsequent activation of the coagulation cascade. As platelet TMEM16F is central in this process, these findings reinforce the rationale of repurposing drugs targeting this protein, such as Niclosamide, for COVID-19 therapy.

pathology↗

Fibrillar-Level Strain Gradients Across the Calcified Bone-Cartilage Interface

The bone-cartilage unit (BCU) is a universal feature in diarthrodial joints, which is mechanically-graded and subjected to shear and compressive strains. Changes in the BCU have been linked to osteoarthritis progression. Here we report existence of a physiological internal strain gradient (pre-strain) across the BCU at the ultrastructural scale of the extracellular matrix constituents, specifically the collagen fibril. We use X-ray scattering that probes changes in the axial periodicity of fibril-level D-stagger of tropocollagen molecules in the matrix fibrils, as a measure of microscopic pre-strain. We find that mineralized collagen nanofibrils in the calcified plate are in tensile pre-strain relative to the underlying trabecular bone. This behaviour contrasts with the previously accepted notion that fibrillar pre-strain (or D-stagger) in collagenous tissues always reduces with mineralization, via reduced hydration and associated swelling pressure. Within the calcified part of the BCU, a finer-scale gradient in pre-strain (0.6% increase over [~]50m) is observed. The increased fibrillar pre-strain is linked to prior research reporting large tissue-level residual strains under compression. The findings may have biomechanical adaptative significance: higher in-built molecular level resilience/damage resistance to physiological compression, and disruption of the molecular-level pre-strains during remodelling of the BCI may be potential factors in osteoarthritis-based degeneration.

bioengineering↗

In vitro discovery and optimization of a human monoclonal antibody that neutralizes neurotoxicity and lethality of cobra snake venom

The monocled cobra (Naja kaouthia) is one of the most feared snakes in Southeast Asia. It is a highly dangerous species with a potent venom deriving its toxicity predominantly from abundant long-chain -neurotoxins. The only specific treatment for snakebite envenoming is antivenom, which is based on animal-derived polyclonal antibodies. Despite the lifesaving importance of these medicines over the past 120 years, and their ongoing role in combating snakebite disease, major limitations in safety, supply consistency, and efficacy creates a need for a new generation of improved treatments based on modern biotechnological techniques. Here, we describe the initial discovery and subsequent optimization of a recombinant human monoclonal immunoglobin G (IgG) antibody against -cobratoxin using phage display technology. Affinity maturation of the parental antibody by light chain-shuffling resulted in an 8-fold increase in affinity, translating to a significant increase in in vitro neutralization potency and in vivo efficacy. While the parental antibody prolonged survival of mice challenged with purified -cobratoxin, the optimized antibody prevented lethality when incubated with N. kaouthia whole venom prior to intravenous injection. This study is the first to demonstrate neutralization of whole snake venom by a single recombinant monoclonal antibody. Importantly, this suggests that for venoms whose toxicity relies on a single predominant toxin group, such as that of N. kaouthia, as little as one monoclonal antibody may be sufficient to prevent lethality, thus providing a tantalizing prospect of bringing recombinant antivenoms based on human monoclonal or oligoclonal antibodies to the clinic. One Sentence SummaryA recombinant human monoclonal immunoglobulin G antibody, discovered and optimized using in vitro methods, was demonstrated to neutralize the lethal effect of whole venom from the monocled cobra in mice via abrogation of -neurotoxin-mediated neurotoxicity.

molecular biology↗

A comprehensive germline variant and expression analyses of ACE2, TMPRSS2 and SARS-CoV-2 activator FURIN genes from the Middle East: Combating SARS-CoV-2 with precision medicine

The severity of the new COVID-19 pandemic caused by the SARS-CoV-2 virus is strikingly variable in different global populations. SARS-CoV-2 uses ACE2 as a cell receptor, TMPRSS2 protease, and FURIN peptidase to invade human cells. Here, we investigated 1,378 whole-exome sequences of individuals from the Middle Eastern populations (Kuwait, Qatar, and Iran) to explore natural variations in the ACE2, TMPRSS2, and FURIN genes. We identified two activating variants (K26R and N720D) in the ACE2 gene that are more common in Europeans than in the Middle Eastern, East Asian, and African populations. We postulate that K26R can activate ACE2 and facilitate binding to S-protein RBD while N720D enhances TMPRSS2 cutting and, ultimately, viral entry. We also detected deleterious variants in FURIN that are frequent in the Middle Eastern but not in the European populations. This study highlights specific genetic variations in the ACE2 and FURIN genes that may explain SARS-CoV-2 clinical disparity. We showed structural evidence of the functionality of these activating variants that increase the SARS-CoV-2 aggressiveness. Finally, our data illustrate a significant correlation between ACE2 variants identified in people from Middle Eastern origins that can be further explored to explain the variation in COVID-19 infection and mortality rates globally.

genetics↗

Identifying Priority Landscapes for Conservation of Snow Leopards in Pakistan

Pakistans total estimated snow leopard habitat is about 80,000 km2 of which about half is considered prime. However, this preliminary demarcation was not always in close agreement with the actual distribution--the discrepancy may be huge at the local and regional level. Recent technological developments like camera trapping and molecular genetics allow for collecting reliable presence records that could be used to construct realistic species distribution based on empirical data and advanced mathematical approaches like MaxEnt. Current study followed this approach to construct accurate distribution of the species in Pakistan. Moreover, movement corridors, among different landscapes, were also identified through the circuit theory. The habitat suitability map, generated from 384 presence points and 28 environmental variables, scored the snow leopards assumed range in Pakistan, from 0 to 0.97. A large shear of previously known range represented low-quality habitat, including areas in lower Chitral, Swat, Astore and Kashmir. Conversely, Khunjerab, Misgar, Chapursan, Qurumber, Broghil, and Central Karakoram represented high-quality habitats. Variables with higher contribution in the MaxEnt model were precipitation of driest month (34%), annual mean temperature (19.5%), mean diurnal range of temperature (9.8%), annual precipitation (9.4%) and river density (9.2). The validation texts suggest a good model fit, and strong prediction power. The connectivity analysis revealed that the population in the Hindukush landscape appears to be more connected with the population in Afghanistan as compared to other populations in Pakistan. Similarly, the Pamir-Karakoram population is better connected with China and Tajikistan, while the Himalayan population was with the population in India. Current study allows for proposing three model landscapes to be considered under GSLEP agenda as regional priority areas, to safeguard safeguard future of the species in the long run. These landsacpes fall in mountain ranges of the Himalaya, Hindu Kush and Karakoram-Pamir, respectively. We also identified gaps in existing protected areas network, and suggest new protected areas in Chitral and Gilgit-Baltistan to protect critical habitats of snow leopard in Pakistan.

zoology↗

Megakaryocytes, erythropoietic and granulopoietic cells express CAL2 antibody in myeloproliferative neoplasms carrying CALR gene mutations

The discovery of mutated Calreticulin (CALR) in myeloproliferative neoplasms (MPN) has provided proof of clonality, diagnostic importance, and influence on prognosis of this pathology. The identification of this MPN-associated driver mutation -currently based on molecular assays- is represented as a major diagnostic criterion for essential thrombocythaemia (ET), pre-fibrotic myelofibrosis and primary myelofibrosis (PMF) in the updated World Health Organization (WHO) 2008 classification. In the present study, we validated by immunohistochemistry the diagnostic usefulness of the monoclonal CAL2 antibody. Cases of acute myeloid leukaemia (AML) and myelodysplastic/ myeloproliferative neoplasms (MDS/MPN) have been also investigated to assess the specificity of CAL2 antibody. For this purpose, the result of the CAL2 immunostaining was compared with the result of molecular assays. Additionally, we investigated by double staining whether expression of mutated CALR can also be demonstrated on cells of the erythroid and myeloid lineage. We confirmed the usefulness of the CAL2 monoclonal antibody in successfully detecting mutant CALR in bone marrow biopsies. We showed that the immune-reactivity of CAL2 was absolutely restricted to the presence of CALR mutations, which were seen only in ET and MDS/MPN biopsies, but not in AML biopsies (14/14). There was 100% concordance in biopsy specimens with the concomitant molecular results. We applied double staining technique and confirmed that a subpopulation of granulopoietic and erythropoietic cells express mutated CALR as demonstrated with the CAL2 antibody in cases of MPNs. This supports the suggestion that the CALR mutations occur in a multipotent progenitor capable of generating both myeloid and erythroid progeny with preferential expansion of megakaryocytic cell lineage as a result of CALR mutation in an immature hematopoietic stem cell.

pathology↗