Mycobacterial Mutagenesis and Drug Resistance Are Controlled by Phosphorylation- and Cardiolipin-Mediated Inhibition of the RecA Coprotease.

Infection with Mycobacterium tuberculosis continues to cause substantial human mortality, in part because of the emergence of antimicrobial resistance. Antimicrobial resistance in tuberculosis is solely the result of chromosomal mutations that modify drug activators or targets, yet the mechanisms controlling the mycobacterial DNA-damage response (DDR) remain incompletely defined. Here, we identify RecA serine 207 as a multifunctional signaling hub that controls the DDR in mycobacteria. RecA S207 is phosphorylated after DNA damage, which suppresses the emergence of antibiotic resistance by selectively inhibiting the LexA coprotease function of RecA without affecting its ATPase or strand exchange functions. Additionally, RecA associates with the cytoplasmic membrane during the mycobacterial DDR, where cardiolipin can specifically inhibit the LexA coprotease function of unmodified, but not S207 phosphorylated, RecA. These findings reveal that RecA S207 controls mutagenesis and antibiotic resistance in mycobacteria through phosphorylation and cardiolipin-mediated inhibition of RecA coprotease function.

Distinct subunit architecture and assembly pattern of DNA gyrase from mycobacteria.

DNA gyrase, the sole negative supercoiling type II topoisomerase, is composed of two subunits, GyrA and GyrB, encoded by the gyrA and gyrB genes, respectively, that form a quaternary complex of A2 B2 . In this study, we have investigated the assembly of mycobacterial DNA gyrase from its individual subunits, a step prerequisite for its activity. Using analytical size-exclusion chromatography, we show that GyrA from Mycobacterium tuberculosis and Mycobacterium smegmatis forms tetramers (A4 ) in solution unlike in Escherichia coli and other bacteria where GyrA exists as a dimer. GyrB, however, persists as a monomer, resembling the pattern found in E. coli. GyrB in both mycobacterial species interacts with GyrA and triggers the dissociation of the GyrA tetramer to facilitate the formation of catalytically active A2 B2 . Despite oligomerisation, the GyrA tetramer retained its DNA binding ability, and DNA binding had no effect on GyrA's oligomeric state in both species. Moreover, the presence of DNA facilitated the assembly of holoenzyme in the case of M. smegmatis by stabilising the GyrA2 B2 tetramer but with little effect in M. tuberculosis. Thus, in addition to the distinct organisation and regulation of the gyr locus in mycobacteria, the enzyme assembly also follows a different pattern.

Assembly and organization of the N-terminal region of mucin MUC5AC: Indications for structural and functional distinction from MUC5B.

Elevated levels of MUC5AC, one of the major gel-forming mucins in the lungs, are closely associated with chronic obstructive lung diseases such as chronic bronchitis and asthma. It is not known, however, how the structure and/or gel-making properties of MUC5AC contribute to innate lung defense in health and drive the formation of stagnant mucus in disease. To understand this, here we studied the biophysical properties and macromolecular assembly of MUC5AC compared to MUC5B. To study each native mucin, we used Calu3 monomucin cultures that produced MUC5AC or MUC5B. To understand the macromolecular assembly of MUC5AC through N-terminal oligomerization, we expressed a recombinant whole N-terminal domain (5ACNT). Scanning electron microscopy and atomic force microscopy imaging indicated that the two mucins formed distinct networks on epithelial and experimental surfaces; MUC5B formed linear, infrequently branched multimers, whereas MUC5AC formed tightly organized networks with a high degree of branching. Quartz crystal microbalance-dissipation monitoring experiments indicated that MUC5AC bound significantly more to hydrophobic surfaces and was stiffer and more viscoelastic as compared to MUC5B. Light scattering analysis determined that 5ACNT primarily forms disulfide-linked covalent dimers and higher-order oligomers (i.e., trimers and tetramers). Selective proteolytic digestion of the central glycosylated region of the full-length molecule confirmed that MUC5AC forms dimers and higher-order oligomers through its N terminus. Collectively, the distinct N-terminal organization of MUC5AC may explain the more adhesive and unique viscoelastic properties of branched, highly networked MUC5AC gels. These properties may generate insight into why/how MUC5AC forms a static, "tethered" mucus layer in chronic muco-obstructive lung diseases.

Similar return to sport between double cortical button and docking techniques for ulnar collateral ligament reconstruction in baseball players.

BACKGROUND AND HYPOTHESIS: A double cortical button technique for ulnar collateral ligament reconstruction (UCLR) has advantages including significant control over graft tensioning, less concern about graft length, and minimized risk of bone tunnel fracture compared with traditional UCLR techniques. This double cortical button technique was recently found to be noninferior in mechanical performance to the traditional docking technique regarding joint strength, joint stiffness, and graft strain. However, clinical outcomes have not been compared between these UCLR techniques. Therefore, the purpose of this study was to determine whether baseball players who underwent UCLR with a double cortical button (double button) technique have similar return-to-sport (RTS) outcomes to baseball players who underwent UCLR with the traditional docking (docking) technique. MATERIALS AND METHODS: Baseball players who underwent primary UCLR from 2011 to 2020 across 2 institutions were identified. Included patients were contacted to complete a follow-up survey evaluating reoperations, RTS, and functional outcome scores. Functional outcome surveys include the Kerlan-Jobe Orthopaedic Clinic score, the Conway-Jobe score, the Andrews-Timmerman elbow score, and the Single Assessment Numeric Evaluation score. RESULTS: Overall, 78 male baseball players (age: 18.9 ± 2.4 years) with an average follow-up of 3.1 ± 2.4 years were evaluated, with 73 of the players being baseball pitchers. Players in the double button group more frequently received palmaris longus autografts (78% vs. 30%) and less frequently received gracilis autografts (22% vs. 58%) compared with players in the docking group (P = .001); however, all other demographic factors were similar between the groups. All players in the double button group were able to RTS in 11.1 ± 2.6 months, whereas 96% of players in the docking group were able to RTS in 13.5 ± 3.4 months (P > .05). All postoperative outcomes and patient-reported outcomes were statistically similar between the groups and remained similar after isolating pitchers only and after separating partial-thickness from full-thickness UCL tears (all P > .05). CONCLUSION: RTS and other postoperative outcomes may be similar between baseball players who underwent UCLR with the double button technique and the docking technique. Although future research may be necessary to strengthen clinical recommendations, these findings provide the first clinical outcomes in light of a recent cadaveric study finding similar elbow strength, joint stiffness, and graft strain compared with the docking technique.

Loss of Activity-Induced Mitochondrial ATP Production Underlies the Synaptic Defects in a Drosophila Model of ALS.

Mutations in the gene encoding vesicle-associated membrane protein B (VAPB) cause a familial form of amyotrophic lateral sclerosis (ALS). Expression of an ALS-related variant of vapb (vapbP58S ) in Drosophila motor neurons results in morphologic changes at the larval neuromuscular junction (NMJ) characterized by the appearance of fewer, but larger, presynaptic boutons. Although diminished microtubule stability is known to underlie these morphologic changes, a mechanism for the loss of presynaptic microtubules has been lacking. By studying flies of both sexes, we demonstrate the suppression of vapbP58S -induced changes in NMJ morphology by either a loss of endoplasmic reticulum (ER) Ca2+ release channels or the inhibition Ca2+/calmodulin (CaM)-activated kinase II (CaMKII). These data suggest that decreased stability of presynaptic microtubules at vapbP58S NMJs results from hyperactivation of CaMKII because of elevated cytosolic [Ca2+]. We attribute the Ca2+ dyshomeostasis to delayed extrusion of cytosolic Ca2+ Suggesting that this defect in Ca2+ extrusion arose from an insufficient response to the bioenergetic demand of neural activity, depolarization-induced mitochondrial ATP production was diminished in vapbP58S neurons. These findings point to bioenergetic dysfunction as a potential cause for the synaptic defects in vapbP58S -expressing motor neurons.SIGNIFICANCE STATEMENT Whether the synchrony between the rates of ATP production and demand is lost in degenerating neurons remains poorly understood. We report that expression of a gene equivalent to an amyotrophic lateral sclerosis (ALS)-causing variant of vesicle-associated membrane protein B (VAPB) in fly neurons decouples mitochondrial ATP production from neuronal activity. Consequently, levels of ATP in mutant neurons are unable to keep up with the bioenergetic burden of neuronal activity. Reduced rate of Ca2+ extrusion, which could result from insufficient energy to power Ca2+ ATPases, results in the accumulation of residual Ca2+ in mutant neurons and leads to alterations in synaptic vesicle (SV) release and synapse development. These findings suggest that synaptic defects in a model of ALS arise from the loss of activity-induced ATP production.

Morpho-functional characterization of the submucosal glands at the nasopharyngeal end of the auditory tube in humans.

BACKGROUND: The auditory tube (AT), an osteocartilaginous channel, connects the nasopharynx to the middle ear cavity. At the nasopharyngeal opening of the AT, there are dense collections of submucosal glands. In a recent article, Valstar et al. proposed these nasopharyngeal tubal glands conglomerate as salivary glands, which starkly contrasts with their previously known anatomy for being a component of the respiratory tract. This study examines the contesting views regarding the taxonomical categorization of the nasopharyngeal tubal glands. MATERIALS AND METHODS: The AT glands in context were examined in human cadavers grossly, and microscopically using routine and special (Hematoxylin and Eosin [H&E] and Periodic acid-Schiff [PAS] respectively), as well as immunohistochemical (for alpha-SMA and salivary amylase) staining methods and compared with the major and minor salivary glands and the submucosal glands in the trachea. Further, a biochemical analysis was performed to detect the presence of salivary amylase in the oral and nasopharyngeal secretions of the four living human subjects, representing major salivary glands and tubal glands, respectively. RESULTS: The submucosal seromucous glands with a surface lining of respiratory epithelium were observed at the nasopharyngeal end of AT. The cells in the tubal glands showed cytoplasmic positivity for alpha-SMA, which indicated the presence of the myoepithelial cells; however, this expression was significantly lower than in the seromucous submucosal glands within the trachea. Salivary alpha-amylase was undetectable in the cadaveric tissue samples. Moreover, the amylase level in the nasopharyngeal swabs was negligible compared to the oral swabs. CONCLUSION: The anatomical location along the respiratory tract, the presence of respiratory epithelium in the overlying mucosa, their morpho-functional resemblance to the seromucous glands in the trachea, and the absence of salivary amylase strongly indicate that the tubal glands are taxonomically different from the salivary glands. Given the available evidence, their existing recognition as a part of the respiratory tract and an integral component of the AT seems more appropriate.

Insights into the Mechanism of Aluminum-Catalyzed Halodefluorination.

Aluminum has been reported to catalyze halodefluorination reactions, where aliphatic fluorine is substituted with a heavier halogen. Although it is known that stoichiometric aluminum halide can perform this reaction, the role of catalytic aluminum halide and organyl alane reagents is not well understood. We investigate the mechanism of the halodefluorination reaction using catalytic aluminum halide and stoichiometric trimethylsilyl halide. We explore the use of B(C6F5)3 as a catalyst to benchmark pathways where aluminum acts either as a Lewis acid catalyst in cooperation with trimethylsilyl halide or as an independent halodefluorination reagent which is subsequently regenerated by trimethylsilyl halide. Computational and experimental results indicate that aluminum acts as an independent halodefluorination reagent and that reactivity trends observed between different halide reagents can be attributed to relative barriers in halide delivery to the organic fragment, which is the rate-limiting step in both the aluminum halide- and B(C6F5)3-catalyzed pathways.

Introducing a novel histopathological scoring system to assess disease activity and chronicity in cutaneous lichen planus: A proposal.

BACKGROUND: Lichen planus (LP) is a chronic inflammatory disorder caused by an autoimmune attack by cytotoxic T-cells. The clinical course is variable, with episodes of remission and exacerbation. A clinicopathological scoring system for cutaneous LP is not available for effectively assessing disease severity and monitoring treatment response. This study was designed with the aim of proposing an objective and reproducible scoring system, comprising histopathological features of active and chronic disease, and to correlate these scores with clinical morphology groups. METHODOLOGY: This is a retrospective study of 200 cases of cutaneous LP, which were categorized into five clinical groups (I-V) at the time of biopsy. The corresponding histopathological feature was assigned a score based on feature of active and chronic disease. Individual scores were summated to calculate a histopathological index (index [AI] and chronicity index [CI]). The comparison of indices between various clinical groups was performed by Mann-Whitney U test. RESULTS: The median AI was lowest (1) for post-inflammatory hyperpigmentation (clinical group I) and highest (7) for the bullous group (clinical group IV). The median CI (7) was highest for the scarring group (clinical group V). The difference between median AI of clinical group I (post-inflammatory hyperpigmentation) and rest of the groups (clinical groups II, III, IV, and V) was statistically significant (p value <0.05). CONCLUSION: We present this clinico-histopathological scoring system as a reliable and facile method of assessing the activity and severity of LP.

Retro-mode: a newer insight into dry age-related macular degeneration (AMD).

The purpose of this study is to study the role of retro-mode (RM) in early detection and to compare it with other preexisting available modalities on multimodal imaging system in dry AMD. A prospective observational cross-sectional study was done between November 2020 and October 2021 which included 409 eyes of 207 patients. For study purpose, eyes were divided into 3 groups according to the size and number of the drusen, viz, group 1: No AMD, group 2: early AMD and group 3: intermediate AMD which was further divided into 2 subgroups, viz, subgroup A: eyes with drusen size 63-125 µm and subgroup B: eyes with drusen size 125-250 µm. Patients with active or treated wet AMD, scarred choroidal neovascular membrane (CNVM), other maculopathies, other retinopathies, high myopia, trauma and glaucoma were excluded from the study. In cases of No AMD and early AMD, a number of drusens detected on RM were statistically not significant compared to fundus autofluorescence (FAF) and color photo (CF), but in intermediate AMD cases, it was statistically significant. While the area involved by drusens calculated by RM was statistically significant compared to both other modalities. When all modalities were compared with enhanced depth imaging-optical coherence tomography (EDI-OCT) at the choroid and chorio-capillary (CC) level and vessel density (VD) on optical coherence tomography angiography (OCTA) at the choroid, capillaries, deep retinal and superficial retinal plexus level; it was only RM which was found to be in sync with these proven modalities in terms of pattern and trend. In the present scenario, RM is found to be a better diagnostic modality in detecting early and a greater number of drusens with area of involvement than other existing modalities. Though superior, as found in this study, this mode cannot replace other modalities at present but only acts as a complementary investigation in early detection of this disease.

The role and diagnostic accuracy of serology for COVID-19.

BACKGROUND: The role and performance of various serological tests for the diagnosis of COVID-19 are unclear. This study aimed to evaluate the performance of seven commercially available serological assays for SARS-CoV-2 antibodies by testing COVID-19 cases and controls. METHODS: Adult patients with fever for > 5 days, admitted to a tertiary-care teaching hospital in South India, were enrolled prospectively between June and December 2020. SARS-CoV-2 RT-PCR confirmed patients were classified as cases, and patients with febrile illness with laboratory-confirmed alternative diagnosis and healthy participants were controls. All participants were tested with SCoV-2 Detect™ IgM ELISA kit and SCoV-2 Detect™ IgG ELISA kit (InBios International, Seattle, USA) (Inbios), SARS-CoV-2 Total and SARS-CoV-2 IgG (Siemens Healthcare Diagnostics Inc., Tarrytown, USA) (Siemens), Roche Elecsys® Anti-SARS-CoV-2 (Roche Diagnostics, Rotkreuz, Switzerland) (Roche), Abbott SARS-CoV-2 IgG (Abbott Diagnostics, IL, USA) (Abbott), and Liaison® SARS-CoV-2 S1/S2 IgG (DiaSorinS.p.A., Saluggia, Italy) (Liaison). The sensitivities, specificities, positive predictive values (PPV), negative predictive values (NPV), and accuracies were compared. RESULTS: There were 303 participants: 153 cases and 150 controls. ELISA detecting anti-S protein antibody was more sensitive (88.9% for IgG and 86.3% for IgM) than the CLIAs (82.4% for total antibodies and 76.5-85.6% for IgG). Among CLIAs, Roche IgG was most sensitive (85.6%) followed by Abbott (83%) and Liaison (83%). Abbot had the best PPV (88.8%) and was more specific (89.3%) than Liaison (82%) and Roche (82%). Siemens IgG was less sensitive (76.5%) than Siemens Total (82.4%). The specificity of all the serological assays was modest (75-90%). Antibody test positivity increased with the duration of illness reaching 90% after 10 days of illness. When cases were compared against pre-pandemic controls, the IgG gave excellent specificity (98-100%). For seroprevalence studies, InBios IgG had the best accuracy (90.8%) with 88.9% sensitivity and 97.6% specificity. CONCLUSION: The serological assays are important adjuncts for the diagnosis of COVID-19 in patients with persistent symptoms, especially in the second week of illness. The value of serological diagnostic tests is limited in the first week of illness and they provide additional value in seroprevalence studies. The diagnostic accuracy of the ELISA and CLIA platforms were comparable.

Genome-wide association study identifies 74 loci associated with educational attainment.

Educational attainment is strongly influenced by social and other environmental factors, but genetic factors are estimated to account for at least 20% of the variation across individuals. Here we report the results of a genome-wide association study (GWAS) for educational attainment that extends our earlier discovery sample of 101,069 individuals to 293,723 individuals, and a replication study in an independent sample of 111,349 individuals from the UK Biobank. We identify 74 genome-wide significant loci associated with the number of years of schooling completed. Single-nucleotide polymorphisms associated with educational attainment are disproportionately found in genomic regions regulating gene expression in the fetal brain. Candidate genes are preferentially expressed in neural tissue, especially during the prenatal period, and enriched for biological pathways involved in neural development. Our findings demonstrate that, even for a behavioural phenotype that is mostly environmentally determined, a well-powered GWAS identifies replicable associated genetic variants that suggest biologically relevant pathways. Because educational attainment is measured in large numbers of individuals, it will continue to be useful as a proxy phenotype in efforts to characterize the genetic influences of related phenotypes, including cognition and neuropsychiatric diseases.

Xist attenuates acute inflammatory response by female cells.

Biological sex influences inflammatory response, as there is a greater incidence of acute inflammation in men and chronic inflammation in women. Here, we report that acute inflammation is attenuated by X-inactive specific transcript (Xist), a female cell-specific nuclear long noncoding RNA crucial for X-chromosome inactivation. Lipopolysaccharide-mediated acute inflammation increased Xist levels in the cytoplasm of female mouse J774A.1 macrophages and human AML193 monocytes. In both cell types, cytoplasmic Xist colocalizes with the p65 subunit of NF-κB. This interaction was associated with reduced NF-κB nuclear migration, suggesting a novel mechanism to suppress acute inflammation. Further supporting this hypothesis, expression of 5' XIST in male cells significantly reduced IL-6 and NF-κB activity. Adoptive transfer of male splenocytes expressing Xist reduced acute paw swelling in male mice indicating that Xist can have a protective anti-inflammatory effect. These findings show that XIST has functions beyond X chromosome inactivation and suggest that XIST can contribute to sex-specific differences underlying inflammatory response by attenuating acute inflammation in women.

Photoreceptor Phosphodiesterase (PDE6): Structure, Regulatory Mechanisms, and Implications for Treatment of Retinal Diseases.

The photoreceptor phosphodiesterase (PDE6) is a member of large family of Class I phosphodiesterases responsible for hydrolyzing the second messengers cAMP and cGMP. PDE6 consists of two catalytic subunits and two inhibitory subunits that form a tetrameric protein. PDE6 is a peripheral membrane protein that is localized to the signal-transducing compartment of rod and cone photoreceptors. As the central effector enzyme of the G-protein coupled visual transduction pathway, activation of PDE6 catalysis causes a rapid decrease in cGMP levels that results in closure of cGMP-gated ion channels in the photoreceptor plasma membrane. Because of its importance in the phototransduction pathway, mutations in PDE6 genes result in various retinal diseases that currently lack therapeutic treatment strategies due to inadequate knowledge of the structure, function, and regulation of this enzyme. This review focuses on recent progress in understanding the structure of the regulatory and catalytic domains of the PDE6 holoenzyme, the central role of the multi-functional inhibitory γ-subunit, the mechanism of activation by the heterotrimeric G protein, transducin, and future directions for pharmacological interventions to treat retinal degenerative diseases arising from mutations in the PDE6 genes.

Flow Cytometry: An Important Diagnostic Tool in Critically Ill Preterm Neonates with Suspected Sepsis.

OBJECTIVE: Sepsis is a major cause of neonatal mortality. The gold standard for diagnosis is blood culture which suffers from low sensitivity and huge turn-around time. Flow cytometry has been extensively applied to malignant disorders and is an upcoming tool for diagnosis of nonmalignant disorders due to its rapidity and accuracy in detecting cells, cell products, and their functional states. The aim of this study was to investigate the utility of flow cytometric expression of neutrophil CD64, monocyte human leukocyte antigen (HLA-DR) and CD16 in diagnosis in suspected preterm neonates. STUDY DESIGN: In total, 100 preterm neonates with clinical signs of sepsis were enrolled in the study. Blood culture, C-reactive protein (CRP) and flow cytometry for nCD64, mHLA-DR, and mCD16 were performed. The neonates were divided into two groups: culture positive and culture negative and CRP and flow cytometric findings compared. ROC analysis was performed to determine the best cut-off for nCD64, mHLA-DR, and mCD16 values along with estimation of sensitivity, specificity, and predictive values. Probability of <0.05 was taken as significant. RESULTS: Out of the 100 enrolled neonates, 34 (34%) were culture positive. CRP was not found to be significantly different in the two groups. Expression of nCD64 (p = 0.03) was significantly upregulated in the blood culture positive cases with a cut-off mean fluorescence intensity (MFI) value = 4.72 and sensitivity of 92% and specificity of 52%. Expression of mCD16 (p = 0.02) was also upregulated in the blood culture positive cases with a cut-off MFI value = 4.9, with sensitivity of 41%, specificity of 83%. CONCLUSION: The study concluded that nCD64 and mCD16 can be potential biomarkers for early diagnosis of neonatal sepsis with a high sensitivity and specificity. KEY POINTS: · Neutrophil CD64 significantly upregulated in septic neonates.. · Monocyte CD16 significantly upregulated in septic neonates.. · C-reactive protein values were not significantly different in septic versus nonseptic neonates..

Revisiting the surgical anatomy of the triangle of doom and the triangle of pain.

Better understanding of the surgical anatomy of the triangle of doom and the triangle of pain with fixed bony landmarks like the anterior superior iliac spine (ASIS) and the pubic symphysis (PS) can help in defining a safe location for trocar placement during laparoscopic surgeries and minimize neurovascular complications. Ten cadavers were dissected bilaterally to explore the surgical anatomy of both the triangles. ASIS and PS were evaluated in relation to the deep inguinal ring, external iliac artery, femoral nerve, and inferior epigastric artery. The deep inguinal ring was located at a depth of ~3 cm, about 4.9 ± 0.56 cm along the y-axis and 6.2 ± 0.94 cm along the x-axis, from the ASIS. The external iliac artery was located ~4.33 ± 0.6 cm along the y-axis and 7.29 ± 0.76 along the x-axis from the ASIS. The inferior epigastric artery was at ~4.31 ± 0.38 cm from the midline at the level of ASIS. This knowledge can help in the surface localization of both the triangles and prevent injury to the various neurovascular structures in relation to these triangles. In the current study, cranial to the ASIS lying at a distance of >5 cm from the midline was observed to be a safe zone for accessory trocar placement. The umbilical port has been observed to be safe for trocar placement. The mean angle between ductus deferens and testicular vessels was observed to be 43.5° ± 4.79°, which could help in determining their relative locations during various surgical procedures.

Therapeutic and prophylactic effects of macrophage-derived small extracellular vesicles in the attenuation of inflammatory pain.

Small extracellular vesicles (sEVs) derived from antigen-presenting cells such as macrophages can induce therapeutically relevant immune responses. Anti-inflammatory miRNAs are elevated in sEVs secreted by RAW 264.7 mouse macrophages after lipopolysaccharide (LPS) stimulation. We observed uptake of these sEVs by primary mouse cortical neurons, microglia and astrocytes followed by downregulation of proinflammatory miRNA target genes in recipient cells. Pre-treating primary microglia with these sEVs decreased pro-inflammatory gene expression. A single intrathecal injection of sEVs derived from LPS stimulated RAW 264.7 cells attenuated mechanical hyperalgesia in the complete Freund's adjuvant (CFA) mouse model of inflammatory pain and formalin induced acute pain. Importantly, sEVs did not alter the normal pain threshold in control mice. RNA sequencing of dorsal horn of the spinal cord showed sEVs-induced modulation of immune regulatory pathways. Further, a single prophylactic intrathecal injection of sEVs two weeks prior, attenuated CFA-induced pain hypersensitivity and was ineffective in formalin model. This indicates that prophylactic sEVs administration can be beneficial in attenuating chronic pain without impacting responses to the protective physiological and acute inflammatory pain. Prophylactic administration of sEVs could form the basis for a safe and novel vaccine-like therapy for chronic pain or as an adjuvant, potentially reducing the dose of drugs needed for pain relief.

Ectopic expression of 35 kDa and knocking down of 78 kDa SG2NAs induce cytoskeletal reorganization, alter membrane sialylation, and modulate the markers of EMT.

SG2NA is a protein of the striatin family that organizes STRIPAK complexes. It has splice variants expressing differentially in tissues. Its 78 kDa isoform regulates cell cycle, maintains homeostasis in the endoplasmic reticulum, and prevents oxidative injuries. The 35 kDa variant is devoid of the signature WD-40 repeats in the carboxy terminal, and its function is unknown. We expressed it in NIH 3T3 cells that otherwise express 78 kDa variant only. These cells (35 EE) have altered morphology, faster rate of migration, and enhanced growth as measured by the MTT assay. Similar phenotypes were also seen in cells where the endogenous 78 kDa isoform was downregulated by siRNA (78 KD). Proteomic analyses showed that several cancer-associated proteins are modulated in both 35 EE and 78 KD cells. The 35 EE cells have diffused actin fibers, distinctive ultrastructure, reduced sialylation, and increased expression of MMP2 & 9. The 78 KD cells also had diffused actin fibers and an upregulated expression of MMP2. In both cells, markers epithelial to mesenchymal transition (EMT) viz, E- & N-cadherins, ß-catenin, slug, vimentin, and ZO-1 were modulated partially in tune with the EMT process. Since NIH 3T3 cells are mesenchymal, we also expressed 35 kDa SG2NA in MCF-7 cells of epithelial origin. In these cells (MCF-7-35), the actin fibers were also diffused and the modulation of the markers was more in tune with the EMT process. However, unlike in 35 EE cells, in MCF-7-35 cells, membrane sialylation rather increased. We infer that ectopic expression of 35 kDa and downregulation of 78 kDa SG2NAs partially induce transformed phenotypes.

Perturbation of monocyte subsets in iron-deficient children - a shift to a pro-inflammatory state?

BACKGROUND: Iron deficiency anemia (IDA) is the most prevalent micronutrient deficiency in preschool children in developing countries including India. IDA is associated with immune perturbation, which is reflected in greater frequency of infections in these children. Recent research has shown three distinct monocyte subsets with distinct functions linked to infectious, inflammatory, and autoimmune diseases. These subsets have not been studied in children with IDA. OBJECTIVE: The aim of the study was to assess the percentage of monocyte population and the three subset populations in children with IDA and to compare the data with age-matched healthy controls. METHODS: Venous blood samples (5 mL) from 40 IDA children and 20 controls were collected after taking informed consent. Monocyte subpopulations were compared across the two groups. The outcome variables were calculated using Students Independent t-test or Mann-Whitney U test. P value of <0.05 was taken as significant. RESULTS: No significant difference was found in the absolute numbers as well as percentages of total monocytes between the control and case (study) group. Children in the IDA group showed a significant (p = 0.03) decrease in the nonclassical subset population when compared to the control group. CONCLUSION: This is the first study done on monocyte subsets in iron-deficient children. Decrease in nonclassical monocytes observed may be associated with a pro-inflammatory state and increased risk of inflammatory and auto immune diseases. Follow-up studies are needed to confirm these findings.

Fear vs. hope in India: Finding the silver lining amid the dark clouds of COVID-19.

COVID-19 has been declared a global pandemic, and the associated high rates of morbidity and mortality have made individuals susceptible to mental health problems that affect their psychological well-being. Although individual strengths can shield the negative impact of adverse conditions, their protective role in the context of COVID-19 has not received much attention. This study examines the relationship between fear of COVID-19 and mental health via rumination through the lens of hope as a personal psychological strength. This study employed a two-wave longitudinal design. Data was collected from 412 Indian participants with a time interval of three months and analyzed using a two-step approach to structural equation modelling. Fear of COVID-19 was found to a have negative effect on mental health through rumination. However, results from moderation analysis support the role of hope as a buffer against the indirect negative impact of fear of COVID-19 on mental health outcomes. As one of the first studies to demonstrate the role of psychological strengths of individuals in coping with the direct and indirect psychological ramifications of COVID-19 over a period of time, it contains important implications for the development of mental health interventions in the face of this global crisis.

Anterior chamber morphology changes in eyes with narrow angles by Scheimpflug imaging: Pilocarpine versus laser peripheral iridotomy.

PURPOSE: To evaluate morphometric variables, like anterior chamber angle (ACA), anterior chamber volume (ACV) and central anterior chamber depth (CACD) after pilocarpine administration and after prophylactic laser peripheral iridotomy (LPI) in eyes with primary angle-closure disease (PACD). DESIGN: Prospective cohort study METHODS: Ninety-one eyes of 91 patients with narrow angles were consecutively enrolled in this prospective interventional study. All patients were classified into primary angle-closure suspect (PACS), primary angle-closure (PAC) and primary angle-closure glaucoma (PACG). If both eyes were eligible, one eye was randomly selected for study inclusion. ACV, ACD and ACA were evaluated using Scheimpflug imaging technology at three time points: at baseline (T0), 45 min after application of pilocarpine before LPI (T1) and at one-month post-LPI (T2). RESULTS: PACS, PAC and PACG groups included 25 (27.4%), 24 (26.3%) and 42 (46.1%) eyes, respectively. At both time points T1 and T2, mean pupil diameter, ACV and ACA changed significantly (P = 0.00). In all subgroups, ACD decreased significantly at T1 and then increased significantly at T2. ACA was widened by 6 degrees in angles < 26 degrees as compared to 3 degrees in > 26 degrees eyes. In PACG group, mean ACV increased significantly between T0 and T2 (P = 0.0). Other parameters like mean cornea volume (P = 0.27), central corneal thickness (P = 0.29) showed no significant change between time points (T0, T1 and T2). Pilocarpine instillation caused a significant increase in ACA, ACV and ACD CONCLUSION: Scheimpflug imaging detected significant changes in ACD post-LPI and post-pilocarpine in all groups. However, ACV changed significantly only in PACS and PACG. CLINICAL TRIALS REGISTRATION: Gels and blots/image manipulation: Author declares that the final image submitted represent the original data. All unprocessed images are with corresponding author and will make available if required.