Discovery of Species-Specific Proteotypic Peptides To Establish a Spectral Library Platform for Identification of Nontuberculosis Mycobacteria from Mass Spectrometry-Based Proteomics.

Nontuberculous mycobacteria are opportunistic bacteria pulmonary and extra-pulmonary infections in humans that closely resemble Mycobacterium tuberculosis. Although genome sequencing strategies helped determine NTMs, a common assay for the detection of coinfection by multiple NTMs with M. tuberculosis in the primary attempt of diagnosis is still elusive. Such a lack of efficiency leads to delayed therapy, an inappropriate choice of drugs, drug resistance, disease complications, morbidity, and mortality. Although a high-resolution LC-MS/MS-based multiprotein panel assay can be developed due to its specificity and sensitivity, it needs a library of species-specific peptides as a platform. Toward this, we performed an analysis of proteomes of 9 NTM species with more than 20 million peptide spectrum matches gathered from 26 proteome data sets. Our metaproteomic analyses determined 48,172 species-specific proteotypic peptides across 9 NTMs. Notably, M. smegmatis (26,008), M. abscessus (12,442), M. vaccae (6487), M. fortuitum (1623), M. avium subsp. paratuberculosis (844), M. avium subsp. hominissuis (580), and M. marinum (112) displayed >100 species-specific proteotypic peptides. Finally, these peptides and corresponding spectra have been compiled into a spectral library, FASTA, and JSON formats for future reference and validation in clinical cohorts by the biomedical community for further translation.

Marine-derived antimicrobial molecules from the sponges and their associated bacteria.

Antimicrobial resistance (AMR) is one of the leading global health issues that demand urgent attention. Very soon the world will have to bear the consequences of increased drug resistance if new anti-infectives are not pumped into the clinical pipeline in a short period. This presses on the need for novel chemical entities, and the marine environment is one such hotspot to look for. The Ocean harbours a variety of organisms, of which from this aspect, "Sponges (Phylum Porifera)" are of particular interest. To tackle the stresses faced due to their sessile and filter-feeding lifestyle, sponges produce various bioactive compounds, which can be tapped for human use. The sponges harbour several microorganisms of different types and in most cases; the microbial symbionts are the actual producers of the bioactive compounds. This review describes the alarming need for the development of new antimicrobials and how marine sponges can contribute to this. Selected antimicrobial compounds from the marine sponges and their associated bacteria have been described. Additionally, measures to tackle the supply problem have been covered, which is the primary obstacle in marine natural product drug discovery.

In Vitro and In Vivo Activity of Gepotidacin against Drug-Resistant Mycobacterial Infections.

Mycobacterial pathogens, including nontuberculous mycobacteria (NTM) and Mycobacterium tuberculosis, are pathogens of significant worldwide interest owing to their inherent drug resistance to a wide variety of FDA-approved drugs as well as causing a broad range of serious infections. Identifying new antibiotics active against mycobacterial pathogens is an urgent unmet need, especially those antibiotics that can bypass existing resistance mechanisms. In this study, we demonstrate that gepotidacin, a first-in-class triazaacenapthylene topoisomerase inhibitor, demonstrates potent activity against M. tuberculosis and M. fortuitum, as well as against other clinically relevant NTM species, including fluoroquinolone-resistant M. abscessus. Furthermore, gepotidacin exhibits concentration-dependent bactericidal activity against various mycobacterial pathogens, synergizes with several drugs utilized for their treatment, and reduces bacterial load in macrophages in intracellular killing assays comparably to amikacin. Additionally, M. fortuitum ATCC 6841 was unable to generate resistance to gepotidacin in vitro. When tested in a murine neutropenic M. fortuitum infection model, gepotidacin caused a significant reduction in bacterial load in various organs at a 10-fold lower concentration than amikacin. Taken together, these findings show that gepotidacin possesses a potentially new mechanism of action that enables it to escape existing resistance mechanisms. Thus, it can be projected as a potent novel lead for the treatment of mycobacterial infections, particularly for NTM, where present therapeutic interventions are extremely limited.

Effect of rhizobacteria on arsenic uptake by macrophyte Eichhornia crassipes (Mart.) Solms.

Wastewater flowing in streams and nallahs across India carries several trace metals, including metalloid arsenic (As), which are considered serious environmental contaminants due to their toxicity, and recalcitrant nature. In this study, we determined the phytoremediation of As by Eichhornia crassipes (Mart.) Solms either alone or in association with plant growth-promoting rhizobacteria. Pseudomonas and Azotobacter inoculation to E. crassipes resulted in enhanced As removal compared to uninoculated control. Co-inoculation with a consortium of Pseudomonas, Azotobacter, Azospirillum, Actinomyces, and Bacillus resulted in a higher As (p < 0.05) phytoaccumulation efficiency. P. aeruginosa strain jogii was found particularly effective in augmenting As removal by E. crassipes. Our findings indicate that the synergistic association of E. crassipes and various rhizobacteria is an effective strategy to enhance removal of As and thus may be utilized as an efficient biological alternative for the removal of this metalloid from wastewaters.

MALDI-TOF mass spectrometry: An emerging tool for unequivocal identification of non-fermenting Gram-negative bacilli.

BACKGROUND & OBJECTIVES: Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) has been instrumental in revolutionizing microbiological identification, especially in high-throughput laboratories. It has enabled the identification of organisms like non-fermenting Gram-negative bacilli (NFGNB), which has been a challenging task using conventional methods alone. In this study an attempt was made to validate MALDI-TOF MS for the identification of clinical isolates of each of the three most common NFGNB, other than Pseudomonas spp., taking molecular methods as the gold standard. METHODS: One hundred and fifty clinical isolates of NFGNB, confirmed by molecular methods such as Acinetobacter baumannii[oxa-51 polymerase chain reaction (PCR)], Burkholderia cepacia complex (expanded multilocus sequence typing) and Stenotrophomonas maltophilia (species-specific PCR), were taken. Isolated colonies from fresh cultures of all 150 isolates were smeared onto ground steel plate, with and without formic acid extraction step. The identification was carried out using MALDI-TOF MS Biotyper database. RESULTS: A concordance of 100 and 73.33 per cent was found between the molecular techniques and MALDI-TOF MS system in the identification of these isolates up to genus and species levels, respectively. Using a cut-off of 1.9 for reliable identification, rate of species identification rose to 82.66 per cent. Principal component analysis dendrogram and cluster analysis further increased discrimination of isolates. INTERPRETATION & CONCLUSIONS: Our findings showed MALDI-TOF MS-based identification of NFGNB as a good, robust method for high-throughput laboratories.

Tuning the field distribution and fabrication of an Al@ZnO core-shell nanostructure for a SPR-based fiber optic phenyl hydrazine sensor.

We report the fabrication and characterization of a surface plasmon resonance (SPR)-based fiber optic sensor that uses coatings of silver and aluminum (Al)-zinc oxide (ZnO) core-shell nanostructure (Al@ZnO) for the detection of phenyl hydrazine (Ph-Hyd). To optimize the volume fraction (f) of Al in ZnO and the thickness of the core-shell nanostructure layer (d), the electric field intensity along the normal to the multilayer system is simulated using the two-dimensional multilayer matrix method. The Al@ZnO core-shell nanostructure is prepared using the laser ablation technique. Various probes are fabricated with different values of f and an optimized thickness of core-shell nanostructure for the characterization of the Ph-Hyd sensor. The performance of the Ph-Hyd sensor is evaluated in terms of sensitivity. It is found that the Ag/Al@ZnO nanostructure core-shell-coated SPR probe with f = 0.25 and d = 0.040 µm possesses the maximum sensitivity towards Ph-Hyd. These results are in agreement with the simulated ones obtained using electric field intensity. In addition, the performance of the proposed probe is compared with that of probes coated with (i) Al@ZnO nanocomposite, (ii) Al nanoparticles and (iii) ZnO nanoparticles. It is found that the probe coated with an Al@ZnO core-shell nanostructure shows the largest resonance wavelength shift. The detailed mechanism of the sensing (involving chemical reactions) is presented. The sensor also manifests optimum performance at pH 7.

Synergistic effects of Arbuscular mycorrhizal fungi and plant growth promoting rhizobacteria in bioremediation of iron contaminated soils.

Three Arbuscular mycorrhizal fungi (AMF) from Glomus, Acaulospora and Scutellospora, and four plant growth promoting rhizobacteria (PGPR) isolates related to genera Streptomyces, Azotobacter, Pseudomonas and Paenibacillus were found to be effective in phytoremediation of Fe(3+) contaminated soil where Pennisetum glaucum and Sorghum bicolor were growing as host plants. Co-inoculation of AMF and PGPR showed better results in comparison to either, AMF and PGPR under pot conditions. Both AMF and PGPR were able to produce siderophores. AMF and PGPR associated to P. glaucum and S. bicolor plants increased the extent of iron absorption. AMF and PGPR combination exhibited superior (p < 0.01) phytoremediation efficiency with P. glaucum compared to S. bicolor. These findings warrant further investigations of these synergistic interactions and large-scale in situ studies for bioremediation of iron-contaminated soils.

Whole cell screen based identification of spiropiperidines with potent antitubercular properties.

Whole cell based screens to identify hits against Mycobacterium tuberculosis (Mtb), carried out under replicating and non-replicating (NRP) conditions, resulted in the identification of multiple, novel but structurally related spiropiperidines with potent antitubercular properties. These compounds could be further classified into three classes namely 3-(3-aryl-1,2,4-oxadiazol-5-yl)-1'-alkylspiro[indene-1,4'-piperidine] (abbr. spiroindenes), 4-(3-aryl-1,2,4-oxadiazol-5-yl)-1'-alkylspiro[chromene-2,4'-piperidine] (abbr. spirochromenes) and 1'-benzylspiro[indole-1,4'-piperidin]-2(1H)-one (abbr. spiroindolones). Spiroindenes showed ⩾ 4 log10 kill (at 2-12 µM) on replicating Mtb, but were moderately active under non replicating conditions. Whole genome sequencing efforts of spiroindene resistant mutants resulted in the identification of I292L mutation in MmpL3 (Mycobacterial membrane protein Large), required for the assembly of mycolic acid into the cell wall core of Mtb. MIC modulation studies demonstrated that the mutants were cross-resistant to spirochromenes but not to spiroindolones. This Letter describes lead identification efforts to improve potency while reducing the lipophilicity and hERG liabilities of spiroindenes. Additionally, as deduced from the SAR studies, we provide insights regarding the new chemical opportunities that the spiroindolones can offer to the TB drug discovery initiatives.

Discovery of benzothiazoles as antimycobacterial agents: Synthesis, structure-activity relationships and binding studies with Mycobacterium tuberculosis decaprenylphosphoryl-ß-D-ribose 2'-oxidase.

We report the discovery of benzothiazoles, a novel anti-mycobacterial series, identified from a whole cell based screening campaign. Benzothiazoles exert their bactericidal activity against Mycobacterium tuberculosis (Mtb) through potent inhibition of decaprenylphosphoryl-ß-d-ribose 2'-oxidase (DprE1), the key enzyme involved in arabinogalactan synthesis. Specific target linkage and mode of binding were established using co-crystallization and protein mass spectrometry studies. Most importantly, the current study provides insights on the utilization of systematic medicinal chemistry approaches to mitigate safety liabilities while improving potency during progression from an initial genotoxic hit, the benzothiazole N-oxides (BTOs) to the lead-like AMES negative, crowded benzothiazoles (cBTs). These findings offer opportunities for development of safe clinical candidates against tuberculosis. The design strategy adopted could find potential application in discovery of safe drugs in other therapy areas too.

Assessment of Mycobacterium tuberculosis pantothenate kinase vulnerability through target knockdown and mechanistically diverse inhibitors.

Pantothenate kinase (PanK) catalyzes the phosphorylation of pantothenate, the first committed and rate-limiting step toward coenzyme A (CoA) biosynthesis. In our earlier reports, we had established that the type I isoform encoded by the coaA gene is an essential pantothenate kinase in Mycobacterium tuberculosis, and this vital information was then exploited to screen large libraries for identification of mechanistically different classes of PanK inhibitors. The present report summarizes the synthesis and expansion efforts to understand the structure-activity relationships leading to the optimization of enzyme inhibition along with antimycobacterial activity. Additionally, we report the progression of two distinct classes of inhibitors, the triazoles, which are ATP competitors, and the biaryl acetic acids, with a mixed mode of inhibition. Cocrystallization studies provided evidence of these inhibitors binding to the enzyme. This was further substantiated with the biaryl acids having MIC against the wild-type M. tuberculosis strain and the subsequent establishment of a target link with an upshift in MIC in a strain overexpressing PanK. On the other hand, the ATP competitors had cellular activity only in a M. tuberculosis knockdown strain with reduced PanK expression levels. Additionally, in vitro and in vivo survival kinetic studies performed with a M. tuberculosis PanK (MtPanK) knockdown strain indicated that the target levels have to be significantly reduced to bring in growth inhibition. The dual approaches employed here thus established the poor vulnerability of PanK in M. tuberculosis.

Association of transportation noise with cardiovascular diseases.

This comprehensive article delves into the intricate and multifaceted issue of noise pollution, shedding light on its diverse sources, profound health implications, and the economic burden it imposes on societies. Noise pollution is an increasingly prevalent environmental challenge, impacting millions of people worldwide, often without their full awareness of its adverse effects. Drawing from a wealth of scientific research, the article underscores the well-established links between noise pollution and a spectrum of health issues, including cardiovascular diseases, sleep disturbances, and psychological stress. While exploring the sources and consequences of noise pollution, the article highlights the urgent need for a holistic and collaborative approach to mitigate its impact. This entails a combination of regulatory measures, technological innovations, urban planning strategies, and public education campaigns. It is increasingly evident that the detrimental effects of noise pollution extend beyond physical health, encompassing mental and social well-being. The article also addresses the synergistic relationship between noise pollution and other environmental stressors, emphasizing the importance of considering noise in conjunction with factors like air pollution and access to green spaces. It examines the potential of green spaces to mitigate the effects of noise pollution and enhance overall health.

Cardiovascular risk assessment in inflammatory bowel disease with coronary calcium score.

The interplay between inflammatory bowel disease (IBD) and atherosclerotic cardiovascular disease (ASCVD) underscores the intricate connections between chronic inflammation and cardiovascular health. This review explores the multifaceted relationship between these conditions, highlighting the emerging significance of the coronary calcium score as a pivotal tool in risk assessment and management. Chronic inflammation, a hallmark of IBD, has far-reaching systemic effects that extend to the cardiovascular system. Shared risk factors and mechanisms, such as endothelial dysfunction, lipid dysfunction, and microbiome dysregulation, contribute to the elevated ASCVD risk observed in individuals with IBD. Amidst this landscape, the coronary calcium score emerges as a means to quantify calcified plaque within coronary arteries, offering insights into atherosclerotic burden and potential risk stratification. The integration of the coronary calcium score refines cardiovascular risk assessment, enabling tailored preventive strategies for individuals with IBD. By identifying those at elevated risk, healthcare providers can guide interventions, fostering informed shared decision-making. Research gaps persist, prompting further investigation into mechanisms linking IBD and ASCVD, particularly in the context of intermediate mechanisms and early atherosclerotic changes. The potential of the coronary calcium score extends beyond risk assessment-it holds promise for targeted interventions. Randomized trials exploring the impact of IBD-modifying therapies on ASCVD risk reduction can revolutionize preventive strategies. As precision medicine gains prominence, the coronary calcium score becomes a beacon of insight, illuminating the path toward personalized cardiovascular care for individuals living with IBD. Through interdisciplinary collaboration and rigorous research, we embark on a journey to transform the paradigm of preventive medicine and enhance the well-being of this patient population.

Post-Radiotherapy Complications in Ewing Sarcoma: A Case Report and Literature Review.

Ewing's sarcoma (ES), the second most prevalent malignant osseous tumor in children and adolescents, primarily affects the extremities' long bones and pelvic region. Characterized by its aggressive growth, ES often presents with symptoms like swelling, pain, and neurological deficits, impacting various skeletal sites. ES involving the spine, particularly the sacral region, poses a significant challenge due to its rarity, aggressive nature, and limited sensitivity to treatments. We report the case of an 18-year-old male with recurrent metastatic ES presenting with fever, cough, and a lesion in the right humerus. Despite prior treatments and complications including spinal metastasis and cord compression, the patient's condition deteriorated, resulting in an unfortunate outcome. This case highlights the complexities in managing recurrent metastatic ES, emphasizing the need for tailored multidisciplinary approaches and early detection strategies.

Pyrexia of Unknown Origin: A Report of Two Cases.

Pyrexia of unknown origin (PUO) is a prolonged fever lasting several weeks without an identifiable cause despite extensive medical evaluation. Many a time, its cause remains largely unknown even after collecting a detailed medical history, conducting comprehensive physical assessments, and performing various standard laboratory tests and imaging procedures. This case series presents two cases of pyrexia of unknown origin. The first case includes a unique and uncommon presentation of non-Hodgkin's lymphoma. In the second case, the patient's fever remained unexplained after various investigations and treatments. The two documented cases of PUO presented in this report aim to contribute to the understanding of its diverse etiology and diagnostic challenges. By highlighting unique presentations and diagnostic dilemmas, the cases aim to promote awareness and facilitate timely recognition and appropriate management of PUO.

Homo-BacPROTAC-induced degradation of ClpC1 as a strategy against drug-resistant mycobacteria.

Antimicrobial resistance is a global health threat that requires the development of new treatment concepts. These should not only overcome existing resistance but be designed to slow down the emergence of new resistance mechanisms. Targeted protein degradation, whereby a drug redirects cellular proteolytic machinery towards degrading a specific target, is an emerging concept in drug discovery. We are extending this concept by developing proteolysis targeting chimeras active in bacteria (BacPROTACs) that bind to ClpC1, a component of the mycobacterial protein degradation machinery. The anti-Mycobacterium tuberculosis (Mtb) BacPROTACs are derived from cyclomarins which, when dimerized, generate compounds that recruit and degrade ClpC1. The resulting Homo-BacPROTACs reduce levels of endogenous ClpC1 in Mycobacterium smegmatis and display minimum inhibitory concentrations in the low micro- to nanomolar range in mycobacterial strains, including multiple drug-resistant Mtb isolates. The compounds also kill Mtb residing in macrophages. Thus, Homo-BacPROTACs that degrade ClpC1 represent a different strategy for targeting Mtb and overcoming drug resistance.

A Novel Inhibitor against the Biofilms of Non-Tuberculous Mycobacteria.

Non-tuberculous Mycobacteria (NTM), previously classified as environmental microbes, have emerged as opportunistic pathogens causing pulmonary infections in immunocompromised hosts. The formation of the biofilm empowers NTM pathogens to escape from the immune response and antibiotic action, leading to treatment failures. NF1001 is a novel thiopeptide antibiotic first-in-class compound with potent activity against planktonic/replicating and biofilm forms of various NTM species. It is potent against both drug-sensitive and -resistant NTM. It has demonstrated a concentration-dependent killing of replicating and intracellularly growing NTM, and has inhibited and reduced the viability of NTM in biofilms. Combination studies using standard-of-care (SoC) drugs for NTM exhibited synergetic/additive effects, but no antagonism against both planktonic and biofilm populations of Mycobacterium abscessus and Mycobacterium avium. In summary, the activity of NF1001 alone or in combination with SoC drugs projects NF1001 as a promising candidate for the treatment of difficult-to-treat NTM pulmonary diseases (NTM-PD) and cystic fibrosis (CF) in patients.

Overlapping Phenotypes of Alcoholic Cardiomyopathy and Left Ventricular Non-compaction: A Case Report and Discussion of Converging Cardiomyopathies.

Left ventricular non-compaction cardiomyopathy, often known as LVNC, is a form of congenital cardiomyopathy that is extremely uncommon. It is a condition that may be identified by an elevated number of endomyocardial trabeculations as well as an increase in their prominence. Alcoholic cardiomyopathy, also known as ACM, is a non-ischemic form of dilated cardiomyopathy that is characterized by contractile failure and an enlargement of the heart ventricles. It is not entirely known whether or not there is a clinically significant overlap in phenotypic characteristics between the two illnesses. We report a patient who had previously been diagnosed with ACM and who had cardiac MRI results that fit the criteria for both LVNC and ACM.

A Rare Case of Small Bowel Intussusception in an Elderly: A Case Report and Literature Review.

Intussusception, a rare cause of bowel obstruction in adults, is even less common in the elderly population. Unlike pediatric cases, adult intussusception is primarily associated with pathologic diseases acting as lead points, often requiring surgical intervention. We present a case of an 84-year-old male with a medical history significant for multiple comorbidities, who was diagnosed with a large segment jejunojejunal intussusception resulting in small bowel obstruction. Surgical management was recommended, and an exploratory laparotomy with bowel resection was performed, including the excision of the leading point. This case highlights the challenges in diagnosing adult intussusception and the importance of surgical intervention due to the high incidence of associated pathologic diseases.

Frailty in Aging HIV-Positive Individuals: An Evolving Healthcare Landscape.

The life expectancy of people living with HIV (PLWH) has greatly increased due to advancements in combination antiretroviral treatment (cART). However, this longer life has also increased the prevalence of age-related comorbidities, such as frailty, which now manifest sooner in this group. Frailty, a term coined by the insurance industry, has been broadened to include physical, cognitive, and emotional elements and has been recognized as a critical predictor of negative health outcomes. With the median age of PLWH now in the mid-50s, treating frailty is critical given its link to chronic diseases, cognitive decline, and even death. Frailty assessment tools, such as the Frailty Phenotype (FP) and the Frailty Index (FI), are used to identify vulnerable people. Understanding the pathophysiology of frailty in PLWH indicates the role of immunological mechanisms. Frailty screening and management in this group have progressed, with specialized clinics and programs concentrating on multidisciplinary care. Potential pharmacotherapeutic solutions, as well as novel e-health programs and sensors, are in the future of frailty treatment, but it is critical to ensure that frailty evaluation is not exploited to perpetuate ageist healthcare practices. This narrative review investigates the changing healthcare environment for older people living with HIV (OPLWH), notably in high-income countries. It emphasizes the significance of identifying and managing frailty as a crucial feature of OPLWH's holistic care and well-being.

Development and Validation of the Intravenous Infiltration and Extravasation Risk Assessment Tool (IIERAT) for Pediatric Patients.

OBJECTIVE: To develop and validate a new tool viz., Intravenous Infiltration and Extravasation Risk Assessment Tool (IIEART) for assessing risk of fluid extravasation in children. PARTICIPANTS: 120 children (aged 2-18 year) undergoing peripheral intravenous cannulation were recruited from four hospitals of Haryana to determine the IIEART scale's psychometric properties. METHODS: The tool was developed under four phases with Modified Delphi rounds among nine experts. After experts' confirmation of final draft, the reliability and validity of the tool was ascertained. RESULTS: The final IIERAT with 11 items showed good internal consistency (a=0.81) with inter-rater reliability of (k=0.88). To calculate predictive validity, sensitivity and specificity were assessed for 3 consecutive days from the day of cannulation. At a score >21, the sensitivity was 100% and specificity was 100% with area under curve of 1.0 (95% CI 1.0, 1.0) on second day of cannulation. CONCLUSION: The IIEART developed was found to be valid and reliable and can be used by healthcare personnel to predict pediatric patients at risk for intravenous infiltration and extravasation.