Immunoglobulin G4 disease-related retroperitoneal fibrosis: A series of five cases.

Immunoglobulin G4 (IgG4)-related disease has the potential to impact any part of the body, including the walls of large- and medium-sized blood vessels and the ureters. While histopathologic examination is currently the standard method for identifying organ involvement and diagnosing IgG4-related disease (IgG4-RD), obtaining biopsy or surgical samples from vessel or ureteral walls is challenging. Given that patients may display only mild symptoms, non-invasive imaging plays a vital role in both diagnosing and managing IgG4-related diseases. Multidetector CT scans are valuable in establishing the primary diagnosis, identifying anatomical landmarks and assessing their relationships. Involvement of the genitourinary organs, such as the ureter, bladder, urethra, and male and female reproductive organs in IgG4-RD, is infrequent when compared to kidney involvement. The imaging findings may include the presence of a localised mass within or surrounding the affected organ or a generalised enlargement of the organ. This report includes cross-sectional images of five cases of IgG4-RD involving large- and medium-sized blood vessels (the aorta and superior mesenteric artery) and the ureters. Contribution: This case series provides insight into the various imaging appearances of IgG4-related retroperitoneal organ involvement and helps differentiate it radiologically from retroperitoneal fibrosis.

Identification and structural characterization of a pathogenic ARSA missense variant in two consanguineous families from Jammu and Kashmir (India) with late infantile metachromatic leukodystrophy.

BACKGROUND: Metachromatic leukodystrophy (MLD) is a rare lysosomal storage disorder caused by a deficiency of Arylsulfatase A (ARSA) enzyme activity. Its clinical manifestations include progressive motor and cognitive decline. ARSA gene mutations are frequent in MLD. METHODS AND RESULTS: In the present study, whole exome sequencing (WES) was employed to decipher the genetic cause of motor and cognitive decline in proband's of two consanguineous families from J&K (India). Clinical investigations using radiological and biochemical analysis revealed MLD-like features. WES confirmed a pathogenic variant in the ARSA gene. Molecular simulation dynamics was applied for structural characterization of the variant. CONCLUSION: We report the identification of a pathogenic missense variant (c.1174 C > T; p.Arg390Trp) in the ARSA gene in two cases of late infantile MLD from consanguineous families in Jammu and Kashmir, India. Our study utilized genetic analysis and molecular dynamics simulations to identify and investigate the structural consequences of this mutation. The molecular dynamics simulations revealed significant alterations in the structural dynamics, residue interactions, and stability of the ARSA protein harbouring the p.Arg390Trp mutation. These findings provide valuable insights into the molecular mechanisms underlying the pathogenicity of this variant in MLD.

Enrichment of Native and Recombinant Extracellular Vesicles of Mycobacteria.

Most bacteria, including mycobacteria, generate extracellular vesicles (EVs). Since bacterial EVs (bEVs) contain a subset of cellular components, including metabolites, lipids, proteins, and nucleic acids, several groups have evaluated either the native or recombinant versions of bEVs for their protective potency as subunit vaccine candidates. Unlike native EVs, recombinant EVs are molecularly engineered to contain one or more immunogens of interest. Over the last decade, different groups have explored diverse approaches for generating recombinant bEVs. However, here, we report the design, construction, and enrichment of recombinant mycobacterial EVs (mEVs) in mycobacteria. Towards that, we use Mycobacterium smegmatis (Msm), an avirulent soil mycobacterium as the model system. We first describe the generation and enrichment of native EVs of Msm. Then, we describe the design and construction of recombinant mEVs that contain either mCherry, a red fluorescent reporter protein, or EsxA (Esat-6), a prominent immunogen of Mycobacterium tuberculosis. We achieve this by separately fusing mCherry and EsxA N-termini with the C-terminus of a small Msm protein Cfp-29. Cfp-29 is one of the few abundantly present proteins of MsmEVs. The protocol to generate and enrich recombinant mEVs from Msm remains identical to the generation and enrichment of native EVs of Msm.

Genomic islands and their role in fitness traits of two key sepsis-causing bacterial pathogens.

To survive and establish a niche for themselves, bacteria constantly evolve. Toward that, they not only insert point mutations and promote illegitimate recombinations within their genomes but also insert pieces of 'foreign' deoxyribonucleic acid, which are commonly referred to as 'genomic islands' (GEIs). The GEIs come in several forms, structures and types, often providing a fitness advantage to the harboring bacterium. In pathogenic bacteria, some GEIs may enhance virulence, thus altering disease burden, morbidity and mortality. Hence, delineating (i) the GEIs framework, (ii) their encoded functions, (iii) the triggers that help them move, (iv) the mechanisms they exploit to move among bacteria and (v) identification of their natural reservoirs will aid in superior tackling of several bacterial diseases, including sepsis. Given the vast array of comparative genomics data, in this short review, we provide an overview of the GEIs, their types and the compositions therein, especially highlighting GEIs harbored by two important pathogens, viz. Acinetobacter baumannii and Klebsiella pneumoniae, which prominently trigger sepsis in low- and middle-income countries. Our efforts help shed some light on the challenges these pathogens pose when equipped with GEIs. We hope that this review will provoke intense research into understanding GEIs, the cues that drive their mobility across bacteria and the ways and means to prevent their transfer, especially across pathogenic bacteria.

HupB, a nucleoid-associated protein, is critical for survival of Mycobacterium tuberculosis under host-mediated stresses and for enhanced tolerance to key first-line antibiotics.

To survive and establish its niche, Mycobacterium tuberculosis (Mtb) engages in a steady battle against an array of host defenses and a barrage of antibiotics. Here, we demonstrate that Mtb employs HupB, a nucleoid-associated protein (NAP) as its key player to simultaneously battle and survive in these two stress-inducing fronts. Typically, NAPs are key to bacterial survival under a wide array of environmental or host-mediated stresses. Here, we report that for Mtb to survive under different macrophage-induced assaults including acidic pH, nutrient depletion, oxidative and nitrosative stresses, HupB presence is critical. As expected, the hupB knockout mutant is highly sensitive to these host-mediated stresses. Furthermore, Mtb aptly modulates HupB protein levels to overcome these stresses. We also report that HupB aids Mtb to gain tolerance to high levels of rifampicin (RIF) and isoniazid (INH) exposure. Loss of hupB makes Mtb highly susceptible to even short exposures to reduced amounts of RIF and INH. Overexpressing hupB in Mtb or complementing hupB in the hupB knockout mutant triggers enhanced survival of Mtb under these stresses. We also find that upon loss of hupB, Mtb significantly enhances the permeability of its cell wall by modulating the levels of several surface lipids including phthiocerol dimycocerosates (PDIMs), thus possibly influencing overall susceptibility to host-mediated stresses. Loss of hupB also downregulates efflux pump expression possibly influencing increased susceptibility to INH and RIF. Finally, we find that therapeutic targeting of HupB with SD1, a known small molecule inhibitor, significantly enhances Mtb susceptibility to INH and THP-1 macrophages and significantly reduces MIC to INH. Thus, our data strongly indicate that HupB is a highly promising therapeutic target especially for potential combinatorial shortened therapy with reduced INH and RIF doses.

Comparative evaluation of severity of COVID-19 pneumonia on computed tomography of the chest in vaccinated and non-vaccinated individuals: an observational study.

Purpose: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel virus causing an infectious disease, coronavirus disease 2019 (COVID-19). Computed tomography (CT) of the chest plays a significant role in the diagnosis and prognosis of COVID-19 using computed tomography severity scoring (CT-SS). Numerous vaccines are being made available in the world to lessen the effect of the COVID-19 pandemic. The purpose of the current study is to compare the severity of COVID-19 pneumonia using CT-SS in COVID-19-positive vaccinated (Covishield/Oxford-AstraZeneca) and non-vaccinated individuals and to compare the final outcome wherever possible. Material and methods: This observational study was carried out from March 2021 to April 2021. Forty vaccinated and 40 non-vaccinated RT-PCR-positive COVID-19 patients who underwent CT chest during the 4-12th day of illness formed the material of the study. Semi-quantitative scoring was used, and CT-SS was calculated based on the extent of lobar involvement in all the patients. CT-SS was then compared between the vaccinated and non-vaccinated groups and the results analysed. Results: CT scans were performed in 80 patients (40 patients each in the vaccinated and non-vaccinated groups). The majority of patients in the vaccinated group had mild (42.5%) and moderate (37.5%) CT-SS while the majority of patients in the non-vaccinated group had moderate (52.5%) and severe (27.5%) CT-SS score on chest CT. Also, no mortality was observed in the vaccinated group, with 2 deaths in the non-vaccinated group. Conclusions: Covishield vaccine administration reduces the severity of COVID-19 pneumonia as compared to the nonvaccinated group, with a marked reduction in mortality.

Development of DNA Aptamers to Visualize Release of Mycobacterial Membrane-Derived Extracellular Vesicles in Infected Macrophages.

Extracellular vesicles (EVs) have emerged into a novel vaccine platform, a biomarker and a nano-carrier for approved drugs. Their accurate detection and visualization are central to their utility in varied biomedical fields. Owing to the limitations of fluorescent dyes and antibodies, here, we describe DNA aptamer as a promising tool for visualizing mycobacterial EVs in vitro. Employing SELEX from a large DNA aptamer library, we identified a best-performing aptamer that is highly specific and binds at nanomolar affinity to EVs derived from three diverse mycobacterial strains (pathogenic, attenuated and avirulent). Confocal microscopy revealed that this aptamer was not only bound to in vitro-enriched mycobacterial EVs but also detected EVs that were internalized by THP-1 macrophages and released by infecting mycobacteria. To the best of our knowledge, this is the first study that detects EVs released by mycobacteria during infection in host macrophages. Within 4 h, most released mycobacterial EVs spread to other parts of the host cell. We predict that this tool will soon hold huge potential in not only delineating mycobacterial EVs-driven pathogenic functions but also in harboring immense propensity to act as a non-invasive diagnostic tool against tuberculosis in general, and extra-pulmonary tuberculosis in particular.

Dual Parasitization of the Biliary Tree: First Reported Case.

Cases of biliary ascariasis and hydatid cysts in liver and elsewhere are common in endemic areas and are routinely encountered in surgical outpatient departments. We describe the diagnosis and management of a unique case, who presented with manifestations of biliary ascariasis, but on further investigation was found to harbor ascarids as well as ruptured hydatids in his biliary passages. To our knowledge, this is the first reported case of simultaneous parasitization of common bile duct by ascarid and hydatid forms, resulting in obstruction of the biliary system. This report highlights the diversity of presentation and challenges in the management of such cases, when encountered in practice.

Post-LSCS uterocutaneous fistula-utility of magnetic resonance imaging in its diagnosis.

The present report describes one of the rarest complications of cesarean section, uterocutaneous fistula, diagnosed on magnetic resonance imaging (MRI). A 37-year-old female with history of lower segment caesarean section (LSCS) four years previously presented with a chief symptom of discharge from the right end of a Pfannenstiel incision and on further evaluation was found to have uterocutaneous fistula arising from the LSCS scar to the right end of the abdominal incision. Uterocutaneous fistula is a rare delayed complication of LSCS and MRI plays a definitive role in the accurate diagnosis and delineation of the tract. The present case highlights that although rare, uterocutaneous fistulae must be kept in mind in patients presenting with discharge from the abdominal incision site and MRI evaluation should be performed in such cases for appropriate delineation of the tract.

Deworming rates and lack of awareness of the National Deworming Day in the endemic region of Kashmir: an opportunity to improve public health using immunization program infrastructure.

We assessed the level of regular, periodic deworming and awareness of National Deworming Day in the local population in the endemic region of Kashmir by conducting a cross-sectional survey in the local population of patients (or their attendants for patients 18 years of age or younger) who visited the hospital as outpatients or were admitted as inpatients. The study team presented questionnaires with simple questions about deworming and child immunization to 1150 participants, noted responses, and then compiled the data. We found that the level of regular deworming was very low: only 3.7% (43/1150) of respondents regularly dewormed themselves and 16.34% (188/1150) dewormed their children at least once in a year. None of 1150 participants was aware of national deworming day despite having adequate knowledge about the immunization infrastructure. The immunization infrastructure can be used to improve public health in such circumstances.