ABSTRACT
The emerging SARS-CoV-2 variants of concern (VOCs) threaten the effectiveness of current COVID-19 vaccines administered intramuscularly and designed to only target the spike protein. There is a pressing need to develop next-generation vaccine strategies for broader and long-lasting protection. Using adenoviral vectors (Ad) of human and chimpanzee origin, we evaluated Ad-vectored trivalent COVID-19 vaccines expressing spike-1, nucleocapsid, and RdRp antigens in murine models. We show that single-dose intranasal immunization, particularly with chimpanzee Ad-vectored vaccine, is superior to intramuscular immunization in induction of the tripartite protective immunity consisting of local and systemic antibody responses, mucosal tissue-resident memory T cells and mucosal trained innate immunity. We further show that intranasal immunization provides protection against both the ancestral SARS-CoV-2 and two VOC, B.1.1.7 and B.1.351. Our findings indicate that respiratory mucosal delivery of Ad-vectored multivalent vaccine represents an effective next-generation COVID-19 vaccine strategy to induce all-around mucosal immunity against current and future VOC.
Subject(s)
COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , Immunity, Mucosal , Administration, Intranasal , Animals , Antibodies, Viral/blood , Antibodies, Viral/immunology , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , COVID-19/virology , COVID-19 Vaccines/immunology , Cytokines/blood , Genetic Vectors/genetics , Genetic Vectors/immunology , Genetic Vectors/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Neutralization Tests , Nucleocapsid/genetics , Nucleocapsid/immunology , Nucleocapsid/metabolism , Pan troglodytes , SARS-CoV-2/genetics , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolismABSTRACT
Aside from centrally induced trained immunity in the bone marrow (BM) and peripheral blood by parenteral vaccination or infection, evidence indicates that mucosal-resident innate immune memory can develop via a local inflammatory pathway following mucosal exposure. However, whether mucosal-resident innate memory results from integrating distally generated immunological signals following parenteral vaccination/infection is unclear. Here we show that subcutaneous Bacillus Calmette-Guérin (BCG) vaccination can induce memory alveolar macrophages (AMs) and trained immunity in the lung. Although parenteral BCG vaccination trains BM progenitors and circulating monocytes, induction of memory AMs is independent of circulating monocytes. Rather, parenteral BCG vaccination, via mycobacterial dissemination, causes a time-dependent alteration in the intestinal microbiome, barrier function and microbial metabolites, and subsequent changes in circulating and lung metabolites, leading to the induction of memory macrophages and trained immunity in the lung. These data identify an intestinal microbiota-mediated pathway for innate immune memory development at distal mucosal tissues and have implications for the development of next-generation vaccine strategies against respiratory pathogens.
Subject(s)
BCG Vaccine , Macrophages, Alveolar , Trained Immunity , Lung , Vaccination , Immunity, InnateABSTRACT
Inorganic polyphosphate (polyP) is primarily synthesized by Polyphosphate Kinase-1 (PPK-1) and regulates numerous cellular processes, including energy metabolism, stress adaptation, drug tolerance, and microbial pathogenesis. Here, we report that polyP interacts with acyl CoA carboxylases, enzymes involved in lipid biosynthesis in Mycobacterium tuberculosis. We show that deletion of ppk-1 in M. tuberculosis results in transcriptional and metabolic reprogramming. In comparison to the parental strain, the Δppk-1 mutant strain had reduced levels of virulence-associated lipids such as PDIMs and TDM. We also observed that polyP deficiency in M. tuberculosis is associated with enhanced phagosome-lysosome fusion in infected macrophages and attenuated growth in mice. Host RNA-seq analysis revealed decreased levels of transcripts encoding for proteins involved in either type I interferon signaling or formation of foamy macrophages in the lungs of Δppk-1 mutant-infected mice relative to parental strain-infected animals. Using target-based screening and molecular docking, we have identified raloxifene hydrochloride as a broad-spectrum PPK-1 inhibitor. We show that raloxifene hydrochloride significantly enhanced the activity of isoniazid, bedaquiline, and pretomanid against M. tuberculosis in macrophages. Additionally, raloxifene inhibited the growth of M. tuberculosis in mice. This is an in-depth study that provides mechanistic insights into the regulation of mycobacterial pathogenesis by polyP deficiency.
Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Animals , Mice , Molecular Docking Simulation , Raloxifene Hydrochloride/metabolism , Polyphosphates/metabolism , Tuberculosis/microbiology , Metabolic Networks and Pathways , Bacterial Proteins/metabolismABSTRACT
New drugs with novel mechanisms of action are urgently needed to tackle the issue of drug-resistant tuberculosis. Here, we have performed phenotypic screening using the Pathogen Box library obtained from the Medicines for Malaria Venture against Mycobacterium tuberculosis in vitro. We have identified a pyridine carboxamide derivative, MMV687254, as a promising hit. This molecule is specifically active against M. tuberculosis and Mycobacterium bovis Bacillus Calmette-Guérin (M. bovis BCG) but inactive against Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Escherichia coli pathogens. We demonstrate that MMV687254 inhibits M. tuberculosis growth in liquid cultures in a bacteriostatic manner. Surprisingly, MMV687254 was as active as isoniazid in macrophages and inhibited M. tuberculosis growth in a bactericidal manner. Mechanistic studies revealed that MMV687254 is a prodrug and that its anti-mycobacterial activity requires AmiC-dependent hydrolysis. We further demonstrate that MMV687254 inhibits M. tuberculosis growth in macrophages by inducing autophagy. In the present study, we have also carried out a detailed structure-activity relationship study and identified a promising novel lead candidate. The identified novel series of compounds also showed activity against drug-resistant M. bovis BCG and M. tuberculosis clinical strains. Finally, we demonstrate that in contrast to MMV687254, the lead molecule was able to inhibit M. tuberculosis growth in a chronic mouse model of infection. Taken together, we have identified a novel lead molecule with a dual mechanism of action that can be further optimized to design more potent anti-tubercular agents.
Subject(s)
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculosis , Mice , Animals , Antitubercular Agents/pharmacology , Isoniazid , Tuberculosis/prevention & controlABSTRACT
We present the case of a 6-year-old girl who initially presented with acute pelvic pain, ultimately diagnosed with imperforate hymen leading to hematocolpos. Further investigation revealed additional clinical features including academic struggles, mood swings, and cutaneous findings, prompting consideration of a neurocutaneous syndrome. Magnetic Resonance Imaging (MRI) revealed features consistent with tuberous sclerosis complex (TSC), including radial migration lines in the subcortical white matter and an incidental arachnoid cyst. Notably, this case exhibited a unique presentation with absence of typical TSC findings such as subependymal nodules or cortical tubers. Additionally, precocious puberty, rarely associated with TSC, was observed, suggesting a potential link between hypothalamic lesions and hormonal imbalance. This case underscores the importance of comprehensive evaluation in pediatric patients presenting with seemingly unrelated symptoms, as it may unveil underlying conditions necessitating tailored management strategies.
Subject(s)
Hematocolpos , Puberty, Precocious , Tuberous Sclerosis , Humans , Female , Puberty, Precocious/etiology , Tuberous Sclerosis/complications , Tuberous Sclerosis/diagnostic imaging , Child , Hematocolpos/etiology , Hematocolpos/complications , Hematocolpos/diagnostic imaging , Magnetic Resonance Imaging , Hymen/abnormalities , Hymen/diagnostic imaging , Brain/diagnostic imaging , Brain/pathology , Congenital Abnormalities/diagnostic imagingABSTRACT
Cytokine therapy and cytokine-mediated autophagy have been used as prominent host-directed therapy (HDT) approaches to restrain M. tb growth in the host cell. In the present study, we have dissected the anti-tubercular activity of Soybean lectin (SBL) through cytokine-mediated autophagy induction in differentiated THP-1 (dTHP-1) cells. A significant increase in IL-6 expression was observed in both uninfected and mycobacteria infected dTHP-1 cells through the P2RX7 mediated pathway via PI3K/Akt/CREB-dependent signalling after SBL treatment. Inhibition of IL-6 level using IL-6 neutralizing antibody or associated signalling significantly enhanced the mycobacterial load in SBL-treated dTHP-1 cells. Further, autocrine signalling of IL-6 through its receptor-induced Mcl-1 expression activated autophagy via JAK2/STAT3 pathway, and inhibition of this pathway affected autophagy. Finally, blocking the IL-6-regulated autophagy through NSC 33994 (a JAK2 inhibitor) or S63845 (an Mcl-1 inhibitor) led to a notable increase in intracellular mycobacterial growth in SBL-treated cells. Taken together, these results indicate that SBL interacts with P2RX7 to regulate PI3K/Akt/CREB network to release IL-6 in dTHP-1 cells. The released IL-6, in turn, activates the JAK2/STAT3/Mcl-1 pathway upon interaction with IL-6Rα to modulate autophagy that ultimately controls mycobacterial growth in macrophages.
Subject(s)
Interleukin-6 , Mycobacterium tuberculosis , Autophagy , Interleukin-6/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , STAT3 Transcription Factor/metabolism , THP-1 Cells , HumansABSTRACT
A diverse spectrum of benign entities and malignant neoplasms originate from the monotonous mesothelium that lines the serosal membranes of the pleural, pericardial, and peritoneal cavities. The mesothelium of myriad sites shows a common origin from the lateral plate mesoderm; primary mesothelial tumors thus demonstrate similar pathogenesis, imaging findings, and treatment options. Significant changes have been made in the 2021 World Health Organization (WHO) classification schemata of the pleural and pericardial tumors on the basis of recent advances in pathology and genetics. While malignant mesotheliomas are biologically aggressive malignancies that occur primarily in patients exposed to asbestos with attendant poor survival rates, well-differentiated papillary mesothelial tumors and adenomatoid tumors charter a benign clinical course with an excellent prognosis. Mesothelioma in situ is a newly characterized entity represented by recurrent unexplained pleural effusions without any identifiable mass at imaging or thoracoscopy. Immunohistochemical markers based on BAP1, MTAP, CDKN2A, and TRAF7 gene mutations help differentiate diffuse mesotheliomas from benign mesothelial proliferations and localized mesotheliomas. Cross-sectional imaging modalities, including US, CT, MRI, and fluorine 18-fluorodeoxyglucose (FDG) PET/CT, permit diagnosis and play a major role in staging and assessing surgical resectability. Imaging studies are invaluable in providing noninvasive and quantitative assessment of tumor response in patients with unresectable disease. Owing to significant overlap in patient characteristics and pathomorphology, accurate diagnosis based on advanced histopathology techniques and genetic abnormalities is imperative for optimal management and prognostication. While patients with nonepithelioid pleural mesotheliomas benefit from immunotherapy, novel targeted therapies for CDKN2A-, NF2-, and BAP1-altered mesotheliomas are under consideration. © RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.
Subject(s)
Adenomatoid Tumor , Mesothelioma, Malignant , Mesothelioma , Neoplasms, Mesothelial , Pleural Neoplasms , Humans , Positron Emission Tomography Computed Tomography , Mesothelioma/diagnostic imaging , Mesothelioma/therapy , Pleural Neoplasms/pathology , Biomarkers, TumorABSTRACT
PURPOSE: To determine the correlation of angiogenic growth factors and inflammatory cytokines with the clinical phenotype of ocular tuberculosis (OTB). METHODS: Vitreous fluid was analysed for cytokines in patients with OTB and non-OTB uveitis using multiplex fluorescent bead-based flow cytometric assay. The clinical phenotypes were recorded and correlated with vitreous biomarkers. RESULTS: Vitreous humour from OTB patients had elevated levels of interleukin-10 (IL-10), IL-17-A, interferon-gamma (IFN-γ), and tumour necrosis factor-alpha (TNF-α). Angiopoietin (Ang-2) levels were higher in the panuveitis phenotype. OTB posterior uveitis phenotype had relatively higher vascular endothelial growth factor (VEGF) levels and lower fibroblast growth factor (FGF) levels. Additionally, eyes with choroiditis and vasculitis had elevated levels of VEGF and Ang-2 with FGF downregulation. Both IFN-γ and IL-10 were upregulated in the choroiditis phenotype of OTB. CONCLUSION: Angiogenic growth factors and inflammatory cytokines were altered in the vitreous humour of OTB patients. IFN-γ, VEGF, and IL-10 levels are increased in choroiditis and vasculitis phenotypes. Receiver operating characteristic (ROC) curve analysis further emphasized the importance of the IFN-γ assay in the diagnosis of OTB.
Subject(s)
Choroiditis , Tuberculosis, Ocular , Humans , Cytokines/metabolism , Interleukin-10 , Vascular Endothelial Growth Factor A , Tuberculosis, Ocular/diagnosis , Intercellular Signaling Peptides and Proteins , Interferon-gamma , PhenotypeABSTRACT
PURPOSE: To describe a technique of displacement of submacular hemorrhage (SMH) using subretinal injection of balanced salt solution and filtered air. METHODS: Patients presenting within 2 weeks of massive SMH (>4 disk diameter) were prospectively included. All patients underwent 25-gauge pars plana vitrectomy, posterior vitreous detachment, injection of subretinal balanced salt solution and filtered air followed by partial fluid air exchange, 20% sulfur hexafluoride tamponade, and heads-up positioning postoperatively. Degree of displacement of SMH was assessed at 1 month and change in best-corrected visual acuity was assessed at 3 months. RESULTS: Ten patients with massive SMH who underwent the aforementioned procedure were included. Complete displacement of bleed from the macula was achieved in nine (90%) of 10 eyes at 1 month. There was significant improvement in best-corrected visual acuity from baseline at 1 month ( P = 0.015) and 3 months ( P = 0.043). CONCLUSION: Pars plana vitrectomy with injection of subretinal balanced salt solution and filtered air was well-tolerated and efficacious in displacing large and thick SMH in patients operated within 2 weeks of onset of symptoms.
Subject(s)
Macula Lutea , Tissue Plasminogen Activator , Humans , Fibrinolytic Agents/therapeutic use , Treatment Outcome , Vitrectomy/methods , Injections, Intraocular , Retinal Hemorrhage/surgery , Retinal Hemorrhage/diagnosis , Retrospective StudiesABSTRACT
The Mycobacterium tuberculosis genome harbors nine toxin-antitoxin (TA) systems that are members of the mazEF family, unlike other prokaryotes, which have only one or two. Although the overall tertiary folds of MazF toxins are predicted to be similar, it is unclear how they recognize structurally different RNAs and antitoxins with divergent sequence specificity. Here, we have expressed and purified the individual components and complex of the MazEF6 TA system from M. tuberculosis. Size exclusion chromatography-multiangle light scattering (SEC-MALS) was performed to determine the oligomerization status of the toxin, antitoxin, and the complex in different stoichiometric ratios. The relative stabilities of the proteins were determined by nano-differential scanning fluorimetry (nano-DSF). Microscale thermophoresis (MST) and yeast surface display (YSD) were performed to measure the relative affinities between the cognate toxin-antitoxin partners. The interaction between MazEF6 complexes and cognate promoter DNA was also studied using MST. Analysis of paired-end RNA sequencing data revealed that the overexpression of MazF6 resulted in differential expression of 323 transcripts in M. tuberculosis. Network analysis was performed to identify the nodes from the top-response network. The analysis of mRNA protection ratios resulted in identification of putative MazF6 cleavage site in its native host, M. tuberculosis. IMPORTANCE M. tuberculosis harbors a large number of type II toxin-antitoxin (TA) systems, the exact roles for most of which are unclear. Prior studies have reported that overexpression of several of these type II toxins inhibits bacterial growth and contributes to the formation of drug-tolerant populations in vitro. To obtain insights into M. tuberculosis MazEF6 type II TA system function, we determined stability, oligomeric states, and binding affinities of cognate partners with each other and with their promoter operator DNA. Using RNA-seq data obtained from M. tuberculosis overexpression strains, we have identified putative MazF6 cleavage sites and targets in its native, cellular context.
Subject(s)
Antitoxins , Mycobacterium tuberculosis , Toxin-Antitoxin Systems , Tuberculosis , Antitoxins/genetics , Antitoxins/metabolism , Bacterial Proteins/metabolism , Humans , Mycobacterium tuberculosis/metabolism , Toxin-Antitoxin Systems/geneticsABSTRACT
Virtually all SARS-CoV-2 vaccines currently in clinical testing are stored in a refrigerated or frozen state prior to use. This is a major impediment to deployment in resource-poor settings. Furthermore, several of them use viral vectors or mRNA. In contrast to protein subunit vaccines, there is limited manufacturing expertise for these nucleic-acid-based modalities, especially in the developing world. Neutralizing antibodies, the clearest known correlate of protection against SARS-CoV-2, are primarily directed against the receptor-binding domain (RBD) of the viral spike protein, suggesting that a suitable RBD construct might serve as a more accessible vaccine ingredient. We describe a monomeric, glycan-engineered RBD protein fragment that is expressed at a purified yield of 214 mg/l in unoptimized, mammalian cell culture and, in contrast to a stabilized spike ectodomain, is tolerant of exposure to temperatures as high as 100 °C when lyophilized, up to 70 °C in solution and stable for over 4 weeks at 37 °C. In prime:boost guinea pig immunizations, when formulated with the MF59-like adjuvant AddaVax, the RBD derivative elicited neutralizing antibodies with an endpoint geometric mean titer of â¼415 against replicative virus, comparing favorably with several vaccine formulations currently in the clinic. These features of high yield, extreme thermotolerance, and satisfactory immunogenicity suggest that such RBD subunit vaccine formulations hold great promise to combat COVID-19.
Subject(s)
Angiotensin-Converting Enzyme 2/immunology , Antibodies, Viral/biosynthesis , COVID-19 Vaccines/biosynthesis , COVID-19/prevention & control , Receptors, Virus/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/genetics , Animals , Antibodies, Neutralizing/biosynthesis , Binding Sites , COVID-19/immunology , COVID-19/virology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/genetics , Escherichia coli/genetics , Escherichia coli/metabolism , Female , Guinea Pigs , HEK293 Cells , Hot Temperature , Humans , Immunogenicity, Vaccine , Models, Molecular , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Domains , Protein Interaction Domains and Motifs , Protein Stability , Receptors, Virus/chemistry , Receptors, Virus/genetics , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/immunology , SARS-CoV-2/chemistry , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Vaccination , Vaccine PotencyABSTRACT
The extracellular electron transfer (EET)-capable electroactive microorganisms (EAMs) play crucial roles in mineral cycling and interspecies electron transfer in different environments and are used as biocatalysts in microbial electrochemical technologies. Studying EAMs from extreme environments is desired to advance the electromicrobiology discipline, understanding their unique metabolic traits with implications to extreme microbiology, and develop specific bioelectrochemical applications. Here, we present a novel haloalkaliphilic bacterium named Geoalkalibacter halelectricus SAP-1, isolated from a microbial electroactive biofilm enriched from the haloalkaline lake sediments. It is a rod-shaped Gram-negative heterotrophic anaerobe that uses various carbon and energy sources and respires on soluble and insoluble terminal electron acceptors. Besides 16S-rRNA and whole-genome sequence-based phylogeny, the GGDC values of 21.7%, ANI of 78.5%, and 2.77% genomic DNA GC content difference with the closest validly named species Geoalkalibacter ferrihydriticus (DSM 17813T ) confirmed its novelty. When grown with the solid-state electrode as the only electron acceptor, it produced 460 ± 23 µA/cm2 bioelectrocatalytic current, thereby confirming its electroactivity. Further electrochemical analysis revealed the presence of membrane redox components with a high formal potential, putatively involved in the direct mode of EET. These are distinct from EET components reported for any known electroactive microorganisms, including well-studied Geobacter spp., Shewanella spp., and Desulfuromonas acetexigens. The capabilities of G. halelectricus SAP-1 to respire on soluble and insoluble electron acceptors including fumarate, SO4 2- , Fe3+ , and Mn4+ suggests its role in cycling these elements in haloalkaline environments.
Subject(s)
Geobacter , Shewanella , Electrons , Geobacter/genetics , Electron Transport , Shewanella/metabolism , Minerals/metabolismABSTRACT
Toxin-antitoxin (TA) systems are abundantly present in the genomes of various bacterial pathogens. TA systems have been implicated in either plasmid maintenance or protection against phage infection, stress adaptation or disease pathogenesis. The genome of Mycobacterium tuberculosis encodes for more than 90 TA systems and 4 of these belong to the type IV subfamily (MenAT family). The toxins and antitoxins belonging to type IV TA systems share sequence homology with the AbiEii family of nucleotidyl transferases and the AbiEi family of putative transcriptional regulators, respectively. Here, we have performed experiments to understand the role of MenT2, a toxin from the type IV TA system, in mycobacterial physiology and disease pathogenesis. The ectopic expression of MenT2 using inducible vectors does not inhibit bacterial growth in liquid cultures. Bioinformatic and molecular modelling analysis suggested that the M. tuberculosis genome has an alternative start site upstream of the annotated menT2 gene. The overexpression of the reannotated MenT2 resulted in moderate growth inhibition of Mycobacterium smegmatis. We show that both menT2 and menA2 transcript levels are increased when M. tuberculosis is exposed to nitrosative stress, in vitro. When compared to the survival of the wild-type and the complemented strain, the ΔmenT2 mutant strain of M. tuberculosis was more resistant to being killed by nitrosative stress. However, the survival of both the ΔmenT2 mutant and the wild-type strain was similar in macrophages and when exposed to other stress conditions. Here, we show that MenT2 is required for the establishment of disease in guinea pigs. Gross pathology and histopathology analysis of lung tissues from guinea pigs infected with the ∆menT2 strain revealed significantly reduced tissue damage and inflammation. In summary, these results provide new insights into the role of MenT2 in mycobacterial pathogenesis.
Subject(s)
Bacterial Toxins , Mycobacterium tuberculosis , Toxin-Antitoxin Systems , Tuberculosis , Guinea Pigs , Animals , Mycobacterium tuberculosis/metabolism , Bacterial Toxins/genetics , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Toxin-Antitoxin Systems/geneticsABSTRACT
Stress adaptation and virulence of various bacterial pathogens require stringent response pathways involving guanosine pentaphosphate and inorganic polyphosphate (PolyP). In M. tuberculosis, intracellular PolyP levels are maintained by the activities of polyphosphate kinase (PPK-1, PPK-2) and exopolyphosphatases (PPX-1, PPX-2). We demonstrate that these exopolyphosphatases cumulatively contribute to biofilm formation and survival of M. tuberculosis in nutrient limiting, low oxygen growth conditions and in macrophages. Characterization of single (Δppx2) and double knock out strain (dkppx) of M. tuberculosis demonstrated that these exopolyphosphatases are essential for establishing infection in guinea pigs and mice. Transcriptional profiling revealed that relative to the parental strain the expression of genes belonging to DosR regulon were significantly reduced in mid-log phase cultures of dkppx strain. We also show that PolyP inhibited the autophosphorylation activities associated with DosT and DosS sensor kinases. Host RNA-seq analysis revealed that transcripts involved in various antimicrobial pathways such as apoptosis, autophagy, macrophage activation, calcium signalling, innate and T-cell response were differentially expressed in lung tissues of dkppx strain infected mice. Taken together, we demonstrate that enzymes involved in PolyP homeostasis play a critical role in physiology and virulence of M. tuberculosis. These enzymes are attractive targets for developing novel interventions that might be active against drug-sensitive and drug-resistant M. tuberculosis.
Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Animals , Guinea Pigs , Mice , Mycobacterium tuberculosis/genetics , Virulence , MacrophagesABSTRACT
The COVID-19 pandemic has unfolded to be the most challenging global health crisis in a century. In 11 months since its first emergence, according to WHO, the causative infectious agent SARS-CoV-2 has infected more than 100 million people and claimed more than 2.15 million lives worldwide. Moreover, the world has raced to understand the virus and natural immunity and to develop vaccines. Thus, within a short 11 months a number of highly promising COVID-19 vaccines were developed at an unprecedented speed and are now being deployed via emergency use authorization for immunization. Although a considerable number of review contributions are being published, all of them attempt to capture only a specific aspect of COVID-19 or its therapeutic approaches based on ever-expanding information. Here, we provide a comprehensive overview to conceptually thread together the latest information on global epidemiology and mitigation strategies, clinical features, viral pathogenesis and immune responses, and the current state of vaccine development.
Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , COVID-19/prevention & control , Immunity/immunology , Pandemics/prevention & control , Animals , Humans , Immunization/methods , SARS-CoV-2/immunologyABSTRACT
A series of 2,5-disubstituted benzimidazole derivatives was synthesized with the aim to identify compounds with potent anti-TB activity. All the compounds were screened in vitro against cultured Mycobacterium tuberculosis H37 Rv strain and found to be exhibiting MIC99 values in the range of 0.195-100 µM. Out of 43 synthesized compounds, two compounds 11h and 13e showed better anti-TB activity than the reference drug isoniazid.
Subject(s)
Isoniazid , Mycobacterium tuberculosis , Antitubercular Agents/pharmacology , Benzimidazoles/pharmacology , Isoniazid/pharmacology , Microbial Sensitivity Tests , Structure-Activity RelationshipABSTRACT
PURPOSE: To evaluate the feasibility and utility of microscope-integrated optical coherence tomography in patients undergoing full-thickness neurosensory retinal autograft for refractory macular hole (MH)-associated retinal detachment. METHODS: We analyzed two eyes of two patients who had undergone a neurosensory retinal autograft for large MH associated retinal detachment. Both cases had microscope-integrated optical coherence tomography-guided placement and sizing of the retinal autograft. Time taken for obtaining microscope-integrated optical coherence tomography images, morphology of the retinal autograft (intraoperative and postoperative), and anatomic and functional outcomes were noted. RESULTS: The first case had optic disc pit-related maculopathy with a large MH and total retinal detachment. She had undergone a vitrectomy with internal limiting membrane peeling elsewhere. The second patient had a treatment-naive large MH with total retinal detachment. Both patients underwent vitrectomy with microscope-integrated optical coherence tomography-guided autologous neurosensory retinal autograft placement and silicone oil tamponade. At 6 months and 3 months follow-up, respectively, both patients had closed MHs, attached retinas, and improvement in visual acuity. CONCLUSION: Microscope-integrated optical coherence tomography provides intraoperative visualization of MHs and provides real-time feedback regarding dimensions of the retinal autograft, thus aiding in accurate sizing of the graft. This ensures that the autograft fits snugly in the MH, thereby restoring macular structure and improving visual acuity.
Subject(s)
Retinal Detachment , Retinal Perforations , Female , Humans , Retinal Perforations/diagnosis , Retinal Perforations/surgery , Retinal Detachment/diagnosis , Retinal Detachment/surgery , Tomography, Optical Coherence , Endotamponade/methods , Autografts , Retrospective Studies , Vitrectomy/methodsABSTRACT
PURPOSE: AMD genetic studies have revealed various genetic loci as causal to AMD pathology. We have described the genetic complexity of Indian AMD by describing the interaction of genotypes and subsequent changes in protein expression under the influence of environmental factors. This can be utilized to enhance the diagnostic and therapeutic efficacy in AMD patients. DESIGN: Genotype association was studied in 464 participants (AMD =277 & controls = 187) for eight genetic variants and their corresponding protein expression METHODS: SNP analysis and protein expression analysis was carried out in AMD and controls in tandem with longitudinal assessment of protein levels during the course of AMD pathology. ANCOVA and contrast analysis were used to examine the genotypic interactions and corresponding alterations in protein levels. In order to identify the important genetic variants Logistic Regression (LR) modeling was carried out and to authenticate the model Area under the Receiver Operating Characteristic curve (AUROC) were also computed. RESULTS: We have found genetic variants of rs5749482 (TIMP-3), rs11200638 (HTRA1), rs769449 (APOE) and rs6795735 (ADAMTS9) to be associated with AMD, concomitant with significant alterations of studied proteins levels. Analysis also revealed that the genetic interaction between APOE-HTRA1 genotypes and changes in LIPC levels (>6 pg/ug) by one unit change in SNP, play a crucial role in AMD. LR model suggested that the seven factors (including both genetic and environmental) can be utilized to predict the AMD cases with 88% efficacy and 95.6% AUROC. CONCLUSION: Results suggest that diagnostic and therapeutic strategy for Indian AMD must include estimation of genetic interaction and concomitant changes in expression levels of proteins under influence of environmental factors.
Subject(s)
Gene Regulatory Networks , Macular Degeneration/genetics , ADAMTS9 Protein/genetics , Aged , Apolipoproteins E/genetics , Female , Genetic Predisposition to Disease , Genotype , High-Temperature Requirement A Serine Peptidase 1/genetics , Humans , Macular Degeneration/metabolism , Male , Middle Aged , Polymorphism, Single Nucleotide , Tissue Inhibitor of Metalloproteinase-3/geneticsABSTRACT
Anemia is common in patients with cancer and it's pathophysiology is complex and multifactorial . Conventional methods (Serum Iron, serum ferritin, TIBC, TSAT) to diagnosing iron deficiency anemia in cancer patients is affected by cancer type, duration, treatment, infection and inflammation related to cancer. RET-He measure the recent functional availability of iron and the correlation well with iron deficient / restricted erythropoiesis, and it is not affected by infection and inflammation related to cancer so it can be useful marker to rapidly rule out iron deficiency in cancer patients. Material: This is observation longitudinal study and study subjects including all type of diagnosed cancer patients with anemia (Hb <13 gm % in males and <12gm% in females) with or without treatment. Study duration was 18 month and 200 sample size was taken. Complete blood count (Hb, TLC, platelets, MCV, MCH, MCHC, reticulocyte hemoglobin) were analysed on SYSMEX XN 1000i. Serum Ferritin was estimated using AVANTOR CL-1000i and Serum iron, TIBC, TSAT was run on EBRA MANHEIN CHEM 5X machine. Bone marrow examination was done for diagnosis / staging . Iron stores were evaluated by Perl's Prussian blue stain and graded as per criteria laid down by Gale et al. Observation: At a cut off of 28.4 pg, RET-He achieved sensitivity of 96.77 % and specificity of 81.66% with NPV of 99.3% and PPV of 49.2% for iron deficient state in cancer patients. This cut off value rules out iron deficient erythropoiesis, reduces unnecessary iron studies and encourage early treatment of iron deficiency. There is also moderate agreement exist between iron stores of bone marrow and RET-He with Kappa 0.411 and p value <.0001. Conclusion: RET-He is better indicator of IDA in cancer patients as compared to other conventional methods of diagnosing IDA.This study also revealed a direct correlation between RET-He and bone marrow iron stores. In future it is advisable to use RET-He as a predictor of IDA, which is sensitive and specific at particular cut off points in routine evaluation in IDA in cancer patients.