Origin, evolution, and maintenance of gene-strand bias in bacteria.

Gene-strand bias is a characteristic feature of bacterial genome organization wherein genes are preferentially encoded on the leading strand of replication, promoting co-orientation of replication and transcription. This co-orientation bias has evolved to protect gene essentiality, expression, and genomic stability from the harmful effects of head-on replication-transcription collisions. However, the origin, variation, and maintenance of gene-strand bias remain elusive. Here, we reveal that the frequency of inversions that alter gene orientation exhibits large variation across bacterial populations and negatively correlates with gene-strand bias. The density, distance, and distribution of inverted repeats show a similar negative relationship with gene-strand bias explaining the heterogeneity in inversions. Importantly, these observations are broadly evident across the entire bacterial kingdom uncovering inversions and inverted repeats as primary factors underlying the variation in gene-strand bias and its maintenance. The distinct catalytic subunits of replicative DNA polymerase have co-evolved with gene-strand bias, suggesting a close link between replication and the origin of gene-strand bias. Congruently, inversion frequencies and inverted repeats vary among bacteria with different DNA polymerases. In summary, we propose that the nature of replication determines the fitness cost of replication-transcription collisions, establishing a selection gradient on gene-strand bias by fine-tuning DNA sequence repeats and, thereby, gene inversions.

Estimation of the electrochemical active site density of a metal-free carbon-based catalyst using phosphomolybdate (PMo12) as an adsorbate.

A method to estimate the electrochemical active site density (SD) of carbon (C) and nitrogen-doped carbon (N/C-900) using phosphomolybdate (PMo12) as a probe molecule is proposed. The complete coverage of the active sites by the probe molecules is established irrespective of the adsorbate concentration (1, 5, or 10 mM), potential cycling (1 or 10 cycles) and cleaning time (2, 5, or 10 min). A conversion factor derived from a smooth and polished glassy carbon disk of known geometrical area is used to estimate the electrochemical active surface area (ECSA) of the carbon catalyst from the SD. The relatively higher SD values estimated from DC voltammetry than from large-amplitude Fourier-transform alternating-current voltammetry (FTacV) is indicative of the contribution of capacitive charge in the former. Adsorbed probe molecules (PMo12) can readily be desorbed from the catalyst surface by cycling the electrode to lower potentials. The active site density of N/C-900 (∼0.36 × 1019 sites g-1) is higher than that of C (∼0.17 × 1019 sites g-1).

A droplet vitrification cryopreservation protocol for conservation of hops (Humulus lupulus) genetic resources.

Hops (Humulus lupulus L.) is essentially used in the brewing industry as it contributes to flavor, and aroma of beer. However, the genetic diversity of hops is increasingly threatened by diseases, environmental changes, and urbanization. Cryopreservation has emerged as a pivotal strategy for safeguarding and maintaining the genetic diversity of hops. The present work presents a comprehensive study on the cryopreservation of hops, focusing on the development and optimization of a droplet vitrification based cryopreservation protocol. Shoot tips excised from one month old in vitro cultures were precultured on 0.3 M sucrose, dehydrated in a loading solution followed by treatment with PVS2 solution for different durations. Significant effect of PVS2 dehydration was observed on post-thaw survival and regeneration after cryoconservation with maximum 50% post-thaw regeneration observed in shoot tips dehydrated in PVS2 for 30 min. Genetic fidelity of the regenerated plants was confirmed using 30 ISSR markers. Reproducibility of the developed protocol was tested on seven other accessions and post thaw regeneration ranging from 43 to 70% was observed across the accessions. The present study reports a highly efficient protocol for conservation of hops germplasm. The results indicate that droplet vitrification can be used as a reliable and sustainable approach for hop genetic preservation, with high survival rates and minimal genetic alterations observed in cryopreserved samples. To the best of our knowledge, this is the first report on DV based cryopreservation of hops germplasm.

Predicting Pancreatic Cancer in the UK Biobank Cohort Using Polygenic Risk Scores and Diabetes Mellitus.

BACKGROUND & AIMS: Diabetes mellitus (DM) is known to be associated with pancreatic ductal adenocarcinoma (PDAC), particularly new-onset DM (NODM). Others have developed polygenic risk scores (PRS) associated with PDAC risk. We aimed to compare the performance of these PRS in an independent cohort to determine if they can discriminate between NODM and long-standing DM patients with PDAC. METHODS: Cases (1042) and matched cancer-free controls (10,420) were drawn from the UK Biobank. Five PRS models were calculated using single nucleotide polymorphisms (SNPs) from previous studies (Nakatochi, Galeotti, Molina, Jia, and Rashkin) and a combination of these. Regression models were used to assess the association between PDAC and PRS adjusted for ancestry, smoking, DM, waist circumference, and family history of digestive cancer. Receiver operator characteristic curves and area under the curve metrics (AUC) were used to assess the performance of each PRS for classifying PDAC risk. RESULTS: The combined PRS model achieved the highest AUC (0.605), and significantly improved a clinical risk model in this cohort (AUC = 0.83; P = .0002). Individuals within the fifth quintile have a 2.74-fold increased risk of developing PDAC vs those in the first quintile (P < .001), and have a 3.05-fold increased risk of developing PDAC if they have DM vs those without DM (P < .001). The positive predictive value was 11.9% in participants without DM, 23.9% with long-standing DM, and 86.7% with NODM. CONCLUSIONS: The PDAC-related common genetic variants are more strongly associated with DM. This PRS has the potential for targeting individuals with NODM for PDAC secondary screening measures.

Influence of Nitrogen Doping into Carbon on the Activation Barrier of ORR in Alkaline Medium: An Investigation Based on Eyring Analysis.

The oxygen reduction reaction (ORR) is investigated on metal-free carbon (Vulcan XC-72) and nitrogen-doped (∼≤1%) carbon (N/C-900) in 0.1 M KOH. The product distribution (O2 to OH- and HO2-) as a function of overpotential (η) in the temperature range of 293-323 K is analyzed using a rotating ring-disk electrode (RRDE) assembly. The kinetic current due to reduction of O2 to HO2- is estimated and used in the Eyring analysis to determine the change in enthalpy of activation (ΔH#). It is shown that doping of carbon with nitrogen (even with ≤1 wt %) causes substantial increase in the number of active sites (almost 2-fold) and reduction in ΔH# at any η. Moreover, ΔH# is a stronger function of η on N/C-900 as compared to that on the carbon surface.

Distinct regulation of bioenergetics and translation by group I mGluR and NMDAR.

Neuronal activity is responsible for the high energy consumption in the brain. However, the cellular mechanisms draining ATP upon the arrival of a stimulus are yet to be explored systematically at the post-synapse. Here, we provide evidence that a significant fraction of ATP is consumed upon glutamate stimulation to energize mGluR-induced protein synthesis. We find that both mGluR and NMDAR alter protein synthesis and ATP consumption with distinct kinetics at the synaptic-dendritic compartments. While mGluR activation leads to a rapid and sustained reduction in neuronal ATP levels, NMDAR activation has no immediate impact on the same. ATP consumption correlates inversely with the kinetics of protein synthesis for both receptors. We observe a persistent elevation in protein synthesis within 5 minutes of mGluR activation and a robust inhibition of the same within 2 minutes of NMDAR activation, assessed by the phosphorylation status of eEF2 and metabolic labeling. However, a delayed protein synthesis-dependent ATP expenditure ensues after 15 minutes of NMDAR stimulation. We identify a central role for AMPK in the correlation between protein synthesis and ATP consumption. AMPK is dephosphorylated and inhibited upon mGluR activation, while it is phosphorylated upon NMDAR activation. Perturbing AMPK activity disrupts receptor-specific modulations of eEF2 phosphorylation and protein synthesis. Our observations, therefore, demonstrate that the regulation of the AMPK-eEF2 signaling axis by glutamate receptors alters neuronal protein synthesis and bioenergetics.

The effect of synthetic acetylhexapeptide-8 (AH8) on sebaceous function.

OBJECTIVE: This study aims to evaluate the in vitro and clinical effects of topical acetylhexapeptide-8 (AH8) on the appearance of oily skin. METHOD: In vitro SEB-1 human sebocyte cell lines were exposed to different concentrations of AH8, then the lipid content of the sebocytes was measured. For the randomized, controlled, split-face clinical study, participants received AH8 10% lotion formulated in Cetaphil Moisturizing Facial Lotion on one side of their face and the control vehicle lotion on the other side of their face. Facial oiliness was assessed by a trained physician using a three-point grading system, high-resolution digital photographs, and a sebumeter (SM815). Participants also filled out self-assessments of their skin oiliness. RESULTS: The in vitro experiments showed that sebocyte lipid content significantly decreased after AH8 treatment (p < 0.05 at 0.00005% AH8, p = 0.09 at 0.0005% AH8, p < 0.05 at 0.005% AH8, and p < 0.001 at 0.025% AH8). In the clinical study, participants trended towards a 10% reduction (p = 0.16) in sebum production after AH8 treatment in comparison to the vehicle treatment. CONCLUSION: AH8 inhibits the accumulation of lipids in sebocytes in vitro without altering cell proliferation or SREBP-1 expression. Topical AH8 trended towards decreased sebum production in human participants. The use of AH8 may serve as a promising agent to reduce sebocyte lipid production and the appearance of oily skin. RÉSUMÉ: Objectif Cette étude vise à évaluer les effets in vitro et cliniques de l'acétylhexapeptide-8 (AH8) topique sur l'aspect de la peau grasse. Méthode Des lignées cellulaires de sébocytes humains SEB-1 in vitro ont été exposées à différentes concentrations d'AH8, à la suite de quoi la teneur en lipides des sébocytes a été mesurée. Pour l'étude clinique randomisée, contrôlée, en hémi-visage, les participants ont reçu une lotion AH8 10 % formulée dans la lotion hydratante pour le visage Cetaphil d'un côté de leur visage et la lotion témoin de l'autre côté de leur visage. Le sébum du visage a été évalué par un médecin formé à l'aide d'un système de classification à trois points, de photographies numériques à haute résolution et d'un sébumètre (SM815). Les participants ont également rempli des auto-évaluations du sébum de leur peau. Résultats Les expériences in vitro ont montré que la teneur en lipides des sébocytes diminuait significativement après le traitement par AH8 (p < 0.05 à 0.00005 % AH8, p = 0.09 à 0.0005 % AH8, p < 0.001 à 0.025 % AH8). Dans l'étude clinique, les participants avaient tendance à voir leur production de sébum diminuer de 10 % (p = 0.16) après le traitement par AH8, par rapport au traitement par excipient. Conclusion L'AH8 inhibe l'accumulation de lipides dans les sébocytes in vitro sans altérer la prolifération cellulaire ou l'expression de SREBP-1. L'AH8 topique tendait à diminuer la production de sébum chez les participants humains. L'utilisation d'AH8 peut servir d'agent prometteur pour réduire la production de lipides sébocytaires et l'apparence de peau grasse.

Toll-like receptor 4 is a therapeutic target for prevention and treatment of liver failure.

BACKGROUND & AIMS: Toll-like receptor 4 (TLR4) plays an essential role in mediating organ injury in acute liver failure (ALF) and acute-on-chronic liver failure (ACLF). Herein, we assess whether inhibiting TLR4 signaling can ameliorate liver failure and serve as a potential treatment. METHODS: Circulating TLR4 ligands and hepatic TLR4 expression were measured in plasma samples and liver biopsies from patients with cirrhosis. TAK-242 (TLR4 inhibitor) was tested in vivo (10 mg/kg intraperitoneally) in rodent models of ACLF (bile duct ligation + lipopolysaccharide [LPS]; carbon tetrachloride + LPS) and ALF (galactosamine + LPS) and in vitro on immortalized human monocytes (THP-1) and hepatocytes (HHL5). The in vivo therapeutic effect was assessed by coma-free survival, organ injury and cytokine release and in vitro by measuring IL-6, IL-1ß or cell injury (TUNEL), respectively. RESULTS: In patients with cirrhosis, hepatic TLR4 expression was upregulated and circulating TLR4 ligands were increased (p <0.001). ACLF in rodents was associated with a switch from apoptotic cell death in ALF to non-apoptotic forms of cell death. TAK-242 reduced LPS-induced cytokine secretion and cell death (p = 0.002) in hepatocytes and monocytes in vitro. In rodent models of ACLF, TAK-242 administration improved coma-free survival, reduced the degree of hepatocyte cell death in the liver (p <0.001) and kidneys (p = 0.048) and reduced circulating cytokine levels (IL-1ß, p <0.001). In a rodent model of ALF, TAK-242 prevented organ injury (p <0.001) and systemic inflammation (IL-1ß, p <0.001). CONCLUSION: This study shows that TLR4 signaling is a key factor in the development of both ACLF and ALF; its inhibition reduces the severity of organ injury and improves outcome. TAK-242 may be of therapeutic relevance in patients with liver failure. LAY SUMMARY: Toll-like receptor 4 (or TLR4) mediates endotoxin-induced tissue injury in liver failure and cirrhosis. This receptor sensitizes cells to endotoxins, which are produced by gram-negative bacteria. Thus, inhibiting TLR4 signaling with an inhibitor (TAK-242) ameliorates organ injury and systemic inflammation in rodent models of acute and acute-on-chronic liver failure.

COVID-19 Pneumonia with Delayed Viral Clearance in a Patient with Active Drug-resistant Pulmonary Tuberculosis.

COVID pneumonia patient presents with fever, cough, and breathing difficulty. Many respiratory pathogens have such clinical presentations and pulmonary tuberculosis (PTB) is one of them, which is prevalent in the Indian subcontinent. Herein, we are presenting a case of dual infection with severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) and drug-resistant PTB [likely multidrug resistance (MDR)] in a patient with chronic kidney disease (CKD) and type 2 diabetes mellitus, a clinical course further complicated by a prolonged viral clearance. HOW TO CITE THIS ARTICLE: Sarma U, Mishra V, Goel J, Yadav S, Sharma S, Sherawat RK. COVID-19 Pneumonia with Delayed Viral Clearance in a Patient with Active Drug-resistant Pulmonary Tuberculosis. Indian J Crit Care Med 2020;24(11):1132-1134.

Tuberculous Adrenal Abscess Presenting as Adrenal Insufficiency in a 4-Year-Old Boy.

We describe the case of a 4.8-year-old boy who presented with adrenal crisis. The advent of symptoms of adrenal insufficiency in the patient was at around 2 years of age. Congenital causes of adrenal insufficiency were considered over acquired etiologies owing to early onset of symptoms. However, on evaluation, he was found to have left adrenal abscess of tuberculous etiology. The aspirate culture grew multidrug-resistant Mycobacterium tuberculosis complex. He was initiated on glucocorticoid and mineralocorticoid replacement, along with second-line antitubercular therapy. Unique features of our case were early presentation, primary adrenal TB causing adrenal insufficiency, unilateral involvement with adrenal abscess localization, no identifiable extra-adrenal site of tubercular dissemination and resistance to first-line TB drugs.

Central Nervous System Symptoms Due to Transient Methemoglobinemia in a Child With G6PD Deficiency.

The authors herein report a 5-year-old child who presented with massive hemolysis, irritability, and cyanosis. The final diagnosis was glucose-6-phosphate dehydrogenase deficiency with associated central nervous system symptoms probably because of concomitantly acquired methemoglobinemia following oxidant drug exposure. The associated acute-onset anemia would have contributed to the development of cerebral anoxia-related seizures and encephalopathy.

Serial changes of cytokines and growth factors in peripheral circulation after right lobe donor hepatectomy.

Cytokines and growth factors have prominent roles in liver regeneration. The aim of this study was to evaluate the biological markers of liver regeneration in healthy donors undergoing right lobe donor hepatectomy for living donor liver transplantation. Twenty-five voluntary liver donors were enrolled. Peripheral blood samples were taken a day before the operation and on postoperative days (PODs) 1, 3, 7, 14, and 42. Levels of hepatocyte growth factor (HGF), interleukin (IL) 6, tumor necrosis factor α (TNF-α), thrombopoietin (TPO), transforming growth factor ß1 (TGF-ß1), interferon (IFN) α, and IFNγ were monitored. The remnant liver volume (RLV) before surgery and regeneration liver volume (RgV) on POD 14 were calculated on computed tomography (CT). RgV/RLV ratio was correlated with the remnant-liver-volume-to-body-weight ratio (RLVBWR). Inverse correlation was observed between RgV/RLV and RLVBWR (r(2) = 0.61; P < 0.001). There was a significant rise of HGF on POD 1 (P = 0.001), POD 7 (P = 0.049), and POD 14 (P = 0.04). TNF-α was elevated on POD 1 (P = 0.004). The levels of IL 6 (P < 0.001) and TPO (P < 0.001) were higher from POD 1 to POD 42. IFNα was higher on POD 14 (P = 0.003) and POD 42 (P = 0.001). There was a significant fall of IFNγ on POD 1 (P = 0.01) and increase on POD 14 (P = 0.04). The levels of TGF-ß1 were higher on POD 14 (P = 0.008) and on POD 42 (P = 0.002). In conclusion, HGF, IL 6, TNF-α, and TPO are involved in the early phase, whereas TGF-ß1 and IFN are involved in the termination phase of liver regeneration. Liver regeneration was observed to be higher in donors with low RLVBWR.

Koebner's Phenomenon in Childhood Henoch-Schönlein Purpura: A Report of Two Cases.

Koebner's phenomenon occurs rarely in connection with Henoch-Schönlein purpura (HSP). We report two children with HSP who developed Koebner's phenomenon on the second day after the onset of rash. The first was an 11-year-old girl with rheumatic heart disease who presented with abdominal pain for 1 month and subsequently developed rash and nephritis. The second patient was a 7-year-old girl who presented with rash and polyarthritis. To the best of our knowledge, Koebner's phenomenon in childhood HSP has not been reported.

N-acetylcysteine in Cleistanthus collinus Poisoning: A Report of Two Cases in Children.

Cleistanthus collinus, also known as Oduvanthalai in Tamil, is the most commonly encountered plant poison in southern India. The leaves are used for poisoning humans (suicide or homicide) and animals (cattle and fish) and as an abortifacient, especially in rural south India. Although this poisoning is commonly reported in adults, data regarding the use of N-acetylcysteine in pediatric poisoning is lacking. We report two previously healthy male siblings of pediatric age group who ingested the liquid extracted from crushed leaves of this plant given to them by their mother as a means of deliberate harm. Both patients developed distal renal tubular acidosis, with hypokalemia. The younger sibling also developed myocardial toxicity. Other significant findings noted include hypocalcemia, hypomagnesemia and elevated liver enzymes. Both patients received supportive care along with N-acetylcysteine infusion, and showed complete recovery within 10 days.

Expression/localization patterns of sirtuins (SIRT1, SIRT2, and SIRT7) during progression of cervical cancer and effects of sirtuin inhibitors on growth of cervical cancer cells.

Sirtuins belong to the family of class III histone deacetylases; its role in neoplasia is controversial as both tumor-suppressive and promoting functions have been reported. There are very few reports available, where expressions of sirtuin isoforms are comprehensively analyzed during neoplasia. Therefore, in the present study, the expression of SIRT1, SIRT2, and SIRT7 during different stages of cervical cancer progression was analyzed. The normal cervical epithelium showed feeble expression of sirtuin isoforms, SIRT1, SIRT2, and SIRT7. A significant increase in SIRT1 expression was noted in the cytoplasm as well as in the nucleus of proliferative layers of cervical epithelium in squamous intraepithelial lesions (SIL); however, in the squamous cell carcinomas (SCC), a heterogeneous pattern of SIRT1 expression varying from low to high was noted. A progressive increase in the expression of both SIRT2 and SIRT7 was noted during cancer progression in the following order: normal < preneoplasia < cancer. Cervical cancer cell lines, HeLa and SiHa, showed higher levels of SIRT1 and SIRT2 in comparison to the immortalized cell counterpart, HaCaT. Specific inhibitors of SIRT1 (Ex527) and SIRT2 (AGK2) impaired the growth of the cervical cancer cells, SiHa, but not of the HaCaT cells. SIRT1 inhibition caused cell death, while SIRT2 inhibition resulted in cell cycle arrest. In conclusion, we report the overexpression of SIRT2 and SIRT7 proteins in cervical cancer and suggest probable application of sirtuin inhibitors as therapeutic targets. Further, a specific increase in the levels of SIRT1 in intraepithelial lesion makes it a promising candidate for identification of preneoplastic changes.

Fulminant BCG Disease in a 7 Month Old Healthy Male Infant.

A seven month old healthy male infant was brought with papular skin lesions all over the body, which became ulcerative with increasing fever and redness within 1 week duration. On examination, Bacilli Calmette Guerin (BCG) scar was ulcerated with discharge; infant was irritable with tachycardia and tachypnea. Investigations revealed pancytopenia, and acid fast bacilli was positive in skin lesions and at BCG scar site. There was progressive worsening of infant's condition, culminating in death.

Neuronal Circuit Dysfunction in Amyotrophic Lateral Sclerosis.

The primary neural circuit affected in Amyotrophic Lateral Sclerosis (ALS) patients is the corticospinal motor circuit, originating in upper motor neurons (UMNs) in the cerebral motor cortex which descend to synapse with the lower motor neurons (LMNs) in the spinal cord to ultimately innervate the skeletal muscle. Perturbation of these neural circuits and consequent loss of both UMNs and LMNs, leading to muscle wastage and impaired movement, is the key pathophysiology observed. Despite decades of research, we are still lacking in ALS disease-modifying treatments. In this review, we document the current research from patient studies, rodent models, and human stem cell models in understanding the mechanisms of corticomotor circuit dysfunction and its implication in ALS. We summarize the current knowledge about cortical UMN dysfunction and degeneration, altered excitability in LMNs, neuromuscular junction degeneration, and the non-cell autonomous role of glial cells in motor circuit dysfunction in relation to ALS. We further highlight the advances in human stem cell technology to model the complex neural circuitry and how these can aid in future studies to better understand the mechanisms of neural circuit dysfunction underpinning ALS.

Loss of p53 epigenetically modulates epithelial to mesenchymal transition in colorectal cancer.

Epithelial to Mesenchymal transition (EMT) drives cancer metastasis and is governed by genetic and epigenetic alterations at multiple levels of regulation. It is well established that loss/mutation of p53 confers oncogenic function to cancer cells and promotes metastasis. Though transcription factors like ZEB1, SLUG, SNAIL and TWIST have been implied in EMT signalling, p53 mediated alterations in the epigenetic machinery accompanying EMT are not clearly understood. This work attempts to explore epigenetic signalling during EMT in colorectal cancer (CRC) cells with varying status of p53. Towards this, we have induced EMT using TGFß on CRC cell lines with wild type, null and mutant p53 and have assayed epigenetic alterations after EMT induction. Transcriptomic profiling of the four CRC cell lines revealed that the loss of p53 confers more mesenchymal phenotype with EMT induction than its mutant counterparts. This was also accompanied by upregulation of epigenetic writer and eraser machinery suggesting an epigenetic signalling cascade triggered by TGFß signalling in CRC. Significant agonist and antagonistic relationships observed between EMT factor SNAI1 and SNAI2 with epigenetic enzymes KDM6A/6B and the chromatin organiser SATB1 in p53 null CRC cells suggest a crosstalk between epigenetic and EMT factors. The observed epigenetic regulation of EMT factor SNAI1 correlates with poor clinical outcomes in 270 colorectal cancer patients taken from TCGA-COAD. This unique p53 dependent interplay between epigenetic enzymes and EMT factors in CRC cells may be exploited for development of synergistic therapies for CRC patients presenting to the clinic with loss of p53.

Gate-to-grave assessment of plastic from recycling to manufacturing of TENG: a comparison between India and Singapore.

This study assesses the viability of recycled plastic-based triboelectric nanogenerators (TENGs) for sustainable energy harvesting in India and Singapore, concurrently examining plastic waste management. Using material flow analysis and life cycle assessment, the findings revealed that in Singapore, waste-to-energy incineration has a lower environmental impact than landfilling and mechanical recycling, attributed to natural gas usage. In India, recycling offsets impacts from incineration and landfilling, contributing to a lower net environmental impact. Economic performance of a TENG module from PET recyclates showed a 20% carbon footprint reduction when scaling up from lab to industrial "freeze-drying" processes. Key challenges in TENG manufacturing processes are also assessed for future development. This research highlights the potential of recycled plastic-based TENGs in sustainable energy and waste management.