Plasmodium falciparum contains functional SCF and CRL4 ubiquitin E3 ligases, and CRL4 is critical for cell division and membrane integrity.

Protein ubiquitination is essential for cellular homeostasis and regulation of several processes, including cell division and genome integrity. Ubiquitin E3 ligases determine substrate specificity for ubiquitination, and Cullin-RING E3 ubiquitin ligases (CRLs) make the largest group among the ubiquitin E3 ligases. Although conserved and most studied in model eukaryotes, CRLs remain underappreciated in Plasmodium and related parasites. To investigate the CRLs of human malaria parasite Plasmodium falciparum, we generated parasites expressing tagged P. falciparum cullin-1 (PfCullin-1), cullin-2 (PfCullin-2), Rbx1 (PfRbx1) and Skp1 (PfSkp1). PfCullin-1 and PfCullin-2 were predominantly expressed in erythrocytic trophozoite and schizont stages, with nucleocytoplasmic localization and chromatin association, suggesting their roles in different cellular compartments and DNA-associated processes. Immunoprecipitation, in vitro protein-protein interaction, and ubiquitination assay confirmed the presence of a functional Skp1-Cullin-1-Fbox (PfSCF) complex, comprising of PfCullin-1, PfRbx1, PfSkp1, PfFBXO1, and calcyclin binding protein. Immunoprecipitation, sequence analysis, and ubiquitination assay indicated that PfCullin-2 forms a functional human CRL4-like complex (PfCRL4), consisting of PfRbx1, cleavage and polyadenylation specificity factor subunit_A and WD40 repeat proteins. PfCullin-2 knock-down at the protein level, which would hinder PfCRL4 assembly, significantly decreased asexual and sexual erythrocytic stage development. The protein levels of several pathways, including protein translation and folding, lipid biosynthesis and transport, DNA replication, and protein degradation were significantly altered upon PfCullin-2 depletion, which likely reflects association of PfCRL4 with multiple pathways. PfCullin-2-depleted schizonts had poorly delimited merozoites and internal membraned structures, suggesting a role of PfCRL4 in maintaining membrane integrity. PfCullin-2-depleted parasites had a significantly lower number of nuclei/parasite than the normal parasites, indicating a crucial role of PfCRL4 in cell division. We demonstrate the presence of functional CRLs in P. falciparum, with crucial roles for PfCRL4 in cell division and maintaining membrane integrity.

Local Structure in Crystalline, Glass and Melt States of a Hybrid Metal Halide Perovskite.

The pursuit of structure-property relationships in crystalline metal halide perovskites (MHPs) has yielded an unprecedented combination of advantageous characteristics for wide-ranging optoelectronic applications. While crystalline MHP structures are readily accessible through diffraction-based structure refinements, providing a clear view of associated long-range ordering, the local structures in more recently discovered glassy MHP states remain unexplored. Herein, we utilize a combination of Raman spectroscopy, solid-state nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy, in situ X-ray diffraction (XRD) and pair distribution function (PDF) analysis to investigate the coordination environment in crystalline, glass and melt states of the 2D MHP [(S)-(-)-1-(1-naphthyl)ethylammonium]2PbBr4. While crystalline SNPB shows polarization-dependent Raman spectra, the glassy and melt states exhibit broad features and lack polarization dependence. Solid-state NMR reveals disordering at the organic-inorganic interface of the glass due to significant spatial disruption in the tethering ammonium groups and the corresponding dihedral bond angles connecting the naphthyl and ammonium groups, while still preserving substantial naphthyl group registry and remnants of the layering from the crystalline state (deduced from XRD analysis). Moreover, PDF analysis demonstrates the persistence of corner-sharing PbBr6 octahedra in the inorganic framework of the melt/glass phases, but with a loss of structural coherence over length scales exceeding approximately one octahedron due to disorder in the inter- and intraoctahedra bond angles/lengths. These findings deepen our understanding of diverse MHP structural motifs and how structural alterations within the MHP glass affect properties, offering potential for advancing next-generation phase change materials and devices.

Structural Evolution and Photoluminescence Quenching across the FASnI3-xBrx (x = 0-3) Perovskites.

One of the primary methods for band gap tuning in metal halide perovskites has been halide (I/Br) mixing. Despite widespread usage of this type of chemical substitution in perovskite photovoltaics, there is still little understanding of the structural impacts of halide alloying, with the assumption being the formation of ideal solid solutions. The FASnI3-xBrx (x = 0-3) family of compounds provides the first example where the assumption breaks down, as the composition space is broken into two unique regimes (x = 0-2.9; x = 2.9-3) based on their average structure with the former having a 3D and the latter having an extended 3D (pseudo 0D) structure. Pair distribution function (PDF) analyses further suggest a dynamic 5s2 lone pair expression resulting in increasing levels of off-centering of the central Sn as the Br concentration is increased. These antiferroelectric distortions indicate that even the x = 0-2.9 phase space behaves as a nonideal solid-solution on a more local scale. Solid-state NMR confirms the difference in local structure yielding greater insight into the chemical nature and local distributions of the FA+ cation. In contrast to the FAPbI3-xBrx series, a drastic photoluminescence (PL) quenching is observed with x ≥ 1.9 compounds having no observable PL. Our detailed studies attribute this quenching to structural transitions induced by the distortions of the [SnBr6] octahedra in response to stereochemically expressed lone pairs of electrons. This is confirmed through density functional theory, having a direct impact on the electronic structure.

Obesity-related glomerulopathy is associated with elevated WT1 expression in podocytes.

BACKGROUND: The prevalence of obesity is increasing worldwide at an alarming rate. In addition to the increased incidence of cardiovascular and metabolic diseases, obesity is the most potent risk factor for developing chronic kidney disease (CKD). Although systemic events such as hemodynamic factors, metabolic effects, and lipotoxicity were implicated in the pathophysiology of obesity-related glomerulopathy (ORG) and kidney dysfunction, the precise mechanisms underlying the association between obesity and CKD remain unexplored. METHODS: In this study, we employed spontaneous WNIN/Ob rats to investigate the molecular events that promote ORG. Further, we fed a high-fat diet to mice and analyzed the incidence of ORG. Kidney functional parameters, micro-anatomical manifestations, and podocyte morphology were investigated in both experimental animal models. Gene expression analysis in the rodents was compared with human subjects by data mining using Nephroseq and Kidney Precision Medicine Project database. RESULTS: WNIN/Ob rats were presented with proteinuria and several glomerular deformities, such as adaptive glomerulosclerosis, decreased expression of podocyte-specific markers, and effacement of podocyte foot process. Similarly, high-fat-fed mice also showed glomerular injury and proteinuria. Both experimental animal models showed increased expression of podocyte-specific transcription factor WT1. The altered expression of putative targets of WT1 such as E-cadherin, podocin (reduced), and α-SMA (increased) suggests elevated expression of WT1 in podocytes elicits mesenchymal phenotype. Curated data from CKD patients revealed increased expression of WT1 in the podocytes and its precursors, parietal epithelial cells. CONCLUSION: WT1 is crucial during nephron development and has minimal expression in adult podocytes. Our study discovered elevated expression of WT1 in podocytes in obesity settings. Our analysis suggests a novel function for WT1 in the pathogenesis of ORG; however, the precise mechanism of WT1 induction and its involvement in podocyte pathobiology needs further investigation.

New arsenals for old armour: Biogenic nanoparticles in the battle against drug-resistant Candidaalbicans.

Candida albicans is a common commensal fungus and fourth most frequent causative agent of nosocomial infections including life-threatening invasive candidiasis in humans. The effectiveness of present antifungal therapies using azoles, polyenes, flucytosine and echinocandins has plateaued in managing fungal infections. The limitations of these antifungal drugs are related to polymorphic morphology, biofilm formation, emergence of drug-resistant strains and production of several virulence factors. Development of new antifungal agents, which can particularly afflict multiple cellular targets and limiting evolving resistant strains are needed. Recently, metal nanoparticles have emerged as a source of new antifungal agents for antifungal formulations. Furthermore, green nanotechnology deals with the use of biosynthetic routes that offer new avenue for synthesizing antifungal nanoparticles coupled with less toxic chemical inventory and environmental sustainability. This article reviews the recent developments on C. albicans pathogenesis, biofilm formation, drug resistance, mode of action of antifungal drugs and antifungal activities of metal nanoparticles. The antifungal efficacy and mode of action of metal nanoparticles are described in the context of prospective therapeutic applications.

HAIRY MERISTEM proteins regulate the WUSCHEL protein levels in mediating CLAVATA3 expression.

The precise regulation of stem cells in the shoot apical meristems (SAMs) involves the function of the homeodomain transcription factor (TF)-WUSCHEL (WUS). WUS has been shown to move from the site of production-the rib-meristem (RM), into overlaying cells of the central zone (CZ), where it specifies stem cells and also regulates the transcription of CLAVATA3 (CLV3). The secreted signalling peptide CLV3 activates a receptor kinase signalling that restricts WUS transcription and also regulates the nuclear gradient of WUS by offsetting nuclear export. WUS has been shown to regulate both CLV3 levels and spatial activation, restricting its expression to a few cells in the CZ. The HAIRY MERISTEM (HAM), a GRASS-domain class of TFs expressed in the RM, has been shown to physically interact with WUS and regulate CLV3 expression. However, the mechanisms by which this interaction regulates CLV3 expression non-cell autonomously remain unclear. Here, we show that HAM function is required for regulating the WUS protein stability, and the CLV3 expression responds to altered WUS protein levels in ham mutants. Thus, HAM proteins non-cell autonomously regulates CLV3 expression.

Comparison of Janani Suraksha Yojana (JSY) and augmented Arogya Laxmi scheme (ALS) in improving maternal and child health outcomes in urban settlements of Hyderabad, South India.

BACKGROUND: India accounts for the largest number of global neonatal deaths with around 20 per 1000 live births. To improve the utilization of government services for institutional deliveries, Augmented Arogya Laxmi Scheme (ALS) was launched in Telangana state of southern India. This study assessed the effectiveness of the Janani Suraksha Yojana (JSY), which combines cash assistance with delivery and post-delivery care, in comparison to ALS in improving the outcomes related to antenatal, natal, and postnatal care in urban settlements of Hyderabad, Telangana, southern India. METHODS: This was a two-year cross-sectional study conducted in 14 urban settlements of Hyderabad city from September 2017- August 2019. All mothers delivered during the 18 months preceding the survey were enrolled after a written informed consent. Field investigators collected data on variables related to socio-demographic characteristics, awareness, and utilization of JSY and ALS programs. Variables related to antenatal history, antenatal care, complications during birth, delivery outcomes, newborn care, and postnatal care till 28 days were assessed. We used multivariable logistic regression model to examine the association between the different maternal, child, and socio-demographic characteristics of the two study groups. RESULTS: A total of 926 mothers were beneficiaries of Janani Suraksha Yojana (JSY) program while 933 mothers were beneficiaries of augmented Arogya Laxmi Scheme (ALS). Mothers in ALS group (AOR 1.71; 95% CI 1.21-2.43) were at increased odds of having more than eight antenatal care (ANC) visits compared to the mothers availing JSY. Mothers in ALS group were at decreased odds of having complications like severe pain in the abdomen (AOR 0.43; 95% CI 0.22-0.86), swelling of legs or feet (AOR 0.59; 95% CI 0.44-0.80) compared to mothers in JSY group. Children of mothers in the ALS group had increased odds of receiving breastfeeding within 30 minutes of birth (AOR 1.46; 95% CI 1.13-1.88) compared to children of mothers in JSY group. CONCLUSIONS: The newly launched augmented ALS led to the increased utilization of the government health facilities and improved the maternal and child health outcomes.

An enumerative pre-processing approach for retinopathy severity grading using an interpretable classifier: a comparative study.

BACKGROUND: Diabetic retinopathy (DR) is a serious eye complication that results in permanent vision damage. As the number of patients suffering from DR increases, so does the delay in treatment for DR diagnosis. To bridge this gap, an efficient DR screening system that assists clinicians is required. Although many artificial intelligence (AI) screening systems have been deployed in recent years, accuracy remains a metric that can be improved. METHODS: An enumerative pre-processing approach is implemented in the deep learning model to attain better accuracies for DR severity grading. The proposed approach is compared with various pre-trained models, and the necessary performance metrics were tabulated. This paper also presents the comparative analysis of various optimization algorithms that are utilized in the deep network model, and the results were outlined. RESULTS: The experimental results are carried out on the MESSIDOR dataset to assess the performance. The experimental results show that an enumerative pipeline combination K1-K2-K3-DFNN-LOA shows better results when compared with other combinations. When compared with various optimization algorithms and pre-trained models, the proposed model has better performance with maximum accuracy, precision, recall, F1 score, and macro-averaged metric of 97.60%, 94.60%, 98.40%, 94.60%, and 0.97, respectively. CONCLUSION: This study focussed on developing and implementing a DR screening system on color fundus photographs. This artificial intelligence-based system offers the possibility to enhance the efficacy and approachability of DR diagnosis.

Heavy metal association with chronic kidney disease of unknown cause in central India-results from a case-control study.

BACKGROUND: Chronic Kidney Disease of unknown cause (CKDu) a disease of exclusion, and remains unexplained in various parts of the world, including India. Previous studies have reported mixed findings about the role of heavy metals or agrochemicals in CKDu. These studies compared CKDu with healthy controls but lacked subjects with CKD as controls. The purpose of this study was to test the hypothesis whether heavy metals, i.e. Arsenic (As), Cadmium (Cd), Lead (Pb), and Chromium (Cr) are associated with CKDu, in central India. METHODS: The study was conducted in a case-control manner at a tertiary care hospital. CKDu cases (n = 60) were compared with CKD (n = 62) and healthy subjects (n = 54). Blood and urine levels of As, Cd, Pb, and Cr were measured by Inductively Coupled Plasma- Optical Emission Spectrometry. Pesticide use, painkillers, smoking, and alcohol addiction were also evaluated. The median blood and urine metal levels were compared among the groups by the Kruskal-Wallis rank sum test. RESULTS: CKDu had significantly higher pesticide and surface water usage as a source of drinking water. Blood As levels (median, IQR) were significantly higher in CKDu 91.97 (1.3-132.7) µg/L compared to CKD 4.5 (0.0-58.8) µg/L and healthy subjects 39.01 (4.8-67.4) µg/L (p < 0.001) On multinominal regression age and sex adjusted blood As was independently associated with CKDu[ OR 1.013 (95%CI 1.003-1.024) P < .05].Blood and urinary Cd, Pb, and Cr were higher in CKD compared to CKDu (p > .05). Urinary Cd, Pb and Cr were undetectable in healthy subjects and were significantly higher in CKDu and CKD compared to healthy subjects (P = < 0.001). There was a significant correlation of Cd, Pb and Cr in blood and urine with each other in CKDu and CKD subjects as compared to healthy subjects. Surface water use also associated with CKDu [OR 3.178 (95%CI 1.029-9.818) p < .05). CONCLUSION: The study showed an independent association of age and sex adjusted blood As with CKDu in this Indian cohort. Subjects with renal dysfunction (CKDu and CKD) were found to have significantly higher metal burden of Pb, Cd, As, and Cr as compared to healthy controls. CKDu subjects had significantly higher pesticide and surface water usage, which may be the source of differential As exposure in these subjects.

The Patient Population at Homeopathic Outpatient Clinics across India: A Clinical Data Collection Study.

BACKGROUND: Even though several initiatives have been undertaken in different locations worldwide to collect clinical data in homeopathy, it is important to further investigate these aspects in the context of health care in India. OBJECTIVE: The study aimed to gather and analyze patients' clinical data and to derive insights into homeopathic treatment using an internet-based software program for data storage, retrieval and repertorization. METHODS: A multi-center observational study was conducted across 14 homeopathy outpatient clinics in India that are affiliated with the Central Council for Research in Homoeopathy (CCRH). Patient symptoms and demographic details were documented anonymously, and prescriptions were guided by repertorial suggestions from the Vithoulkas Compass software. During follow-up visits, treatment outcome was also recorded using an online assessment form. A retrospective analysis of data on patients' demographics, follow-up visits, morbidity (International Classification of Diseases 11th Revision), rubrics used, prescribed medicines and the level of improvement was achieved using Microsoft Excel-generated pivot tables. RESULTS: Throughout the study duration of one year a total of 2,811 patients attended the 14 outpatient clinics, of whom 2,468 were new patients with a total of 2,172 initial homeopathic prescription entries. Across the study, there were 3,491 prescriptions and 1,628 follow-up consultations for 868 follow-up patients, all of which data were thoroughly analyzed. The highest frequency of patients was in the 20-49 age group, and a higher proportion of the patients overall was female. Musculoskeletal, dermatological and respiratory complaints were the most frequently reported. The rubrics "Desire for sweets" and "Desire for spices" emerged as the most commonly used in the repertorizations. Further, Sulphur stood out as the most commonly prescribed medicine overall. With homeopathic treatment, some degree of clinical improvement was reported in 86% of the follow-up cases. CONCLUSION: Homeopathy is prescribed in CCRH outpatient clinics for a wide range of ailments in people across India, with at least some clinical improvement noted in a high proportion of those patients. The large-scale systematic data collection in these clinics has provided clear insights into the use and clinical value of homeopathy in India, with the potential to build a substantive nationwide data inventory over time.

Association between Usage of Prophylactic AYUSH Medicines and Disease Severity in COVID-19 Patients: A Retrospective Cohort Study.

BACKGROUND: Prior vaccination is often studied for its impact on individuals' post-infection prognosis. Ayurveda, Yoga, Unani, Siddha and Homeopathy (AYUSH) medicines, advised by the Government of India as prophylaxis during the first wave of the coronavirus disease 2019 (COVID-19) pandemic, were consumed by the masses in 2020. A study was therefore undertaken to observe any association between the prior usage of AYUSH prophylactic medicines and post-infection severity as reported by recovered COVID-19 individuals. METHODS: This was a retrospective, multi-centre, cohort study conducted in 21 cities of India from 5th August to 30th November 2020. Data from recovered COVID-19 patients, of either sex or any age, captured information about AYUSH prophylactic medicines intake prior to infection, disease severity, symptomatology, duration of complaints, etc. The study participants were grouped into AYUSH intake and non-intake. Primary composite outcome was the disease clinical course. Secondary clinical outcomes were the rate of and time to clinical recovery. RESULTS: Data of 5,023 persons were analysed. Ayurveda or homeopathic prophylactic medicines were consumed by more than half of the study participants: that is, 56.85% (n = 1,556) and 56.81% (n = 1,555) respectively. The overall adjusted protective effect (PE) of AYUSH prophylactic intake against moderate/severe forms of COVID-19 disease was 56.7% (95% confidence interval [CI], 48.7 to 63.50; p < 0.001). Adjusted PE for homeopathy and Siddha was 52.9% (95% CI, 42.30 to 61.50; p < 0.001) and 59.8% (95% CI, 37.80 to 74.10; p < 0.001), respectively. A statistically significant association was found between AYUSH prophylactic medicine intake and clinical recovery more frequently by the 3rd day of illness (χ2 = 9.01; p = 0.002). Time to resolution of symptoms in the AYUSH intake group was on average 0.3 days earlier than in the non-intake group (p = 0.002). CONCLUSION: AYUSH prophylactics were associated with statistically significant levels of protection against COVID-19 disease severity. Amongst these, previous intake of homeopathy or Siddha medicines was associated with some protection against moderate/severe illness and with a somewhat quicker clinical recovery. Prospective studies with experimental research design are needed to validate the findings of this study. STUDY REGISTRATION: Clinical Trials Registry-India (CTRI/2020/08/027000).

Growth-dependent cr(VI) reduction by Alteromonas sp. ORB2 under haloalkaline conditions: toxicity, removal mechanism and effect of heavy metals.

Bacterial reduction of hexavalent chromium (VI) to chromium (III) is a sustainable bioremediation approach. However, the Cr(VI) containing wastewaters are often characterized with complex conditions such as high salt, alkaline pH and heavy metals which severely impact the growth and Cr(VI) reduction potential of microorganisms. This study investigated Cr(VI) reduction under complex haloalkaline conditions by an Alteromonas sp. ORB2 isolated from aerobic granular sludge cultivated from the seawater-microbiome. Optimum growth of Alteromonas sp. ORB2 was observed under haloalkaline conditions at 3.5-9.5% NaCl and pH 7-11. The bacterial growth in normal culture conditions (3.5% NaCl; pH 7.6) was not inhibited by 100 mg/l Cr(VI)/ As(V)/ Pb(II), 50 mg/l Cu(II) or 5 mg/l Cd(II). Near complete reduction of 100 mg/l Cr(VI) was achieved within 24 h at 3.5-7.5% NaCl and pH 8-11. Cr(VI) reduction by Alteromonas sp. ORB2 was not inhibited by 100 mg/L As(V), 100 mg/L Pb(II), 50 mg/L Cu(II) or 5 mg/L Cd(II). The bacterial cells grew in the medium with 100 mg/l Cr(VI) contained lower esterase activity and higher reactive oxygen species levels indicating toxicity and oxidative stress. In-spite of toxicity, the cells grew and reduced 100 mg/l Cr(VI) completely within 24 h. Cr(VI) removal from the medium was driven by bacterial reduction to Cr(III) which remained in the complex medium. Cr(VI) reduction was strongly linked to aerobic growth of Alteromonas sp. The Cr(VI) reductase activity of cytosolic protein fraction was pronounced by supplementing with NADPH in vitro assays. This study demonstrated a growth-dependent aerobic Cr(VI) reduction by Alteromonas sp. ORB2 under complex haloalkaline conditions akin to wastewaters.

Determinants of Poison-related Mortality in Tertiary Care Hospital, South India.

Aims and background: Acute poisoning is one of the most common emergencies in India and around the world. Understanding the factors associated with mortality can aid us in devising appropriate preventive strategies to curtail deaths due to poisoning. Purpose of this study is to find various factors that determine the mortality among acute poisoning cases admitted in a tertiary care center. Materials and methods: A retrospective hospital records-based study was conducted at Chengalpattu Medical College Hospital. The study included 2,123 cases of various poisoning cases admitted for a year from January to December 2022. Cases of bites, stings, drowning, and hanging were excluded. Information on sociodemographic profile, type of poison, time since ingestion and admission, and treatment outcome were collected using a structured pro forma. Results: The mean age of the study population was 29.90 ± 14.98 years. Poisoning was found to be predominantly among males (56.42%) and residents of rural areas (58%). Insecticide consumption (27.0%) was the most common modality, followed by oleander poisoning (20%), corrosive poison (17%), rat poison (15%), tablet poison (13%), and other poisons. The overall case fatality rate (CFR) was 5.2%, with the highest CFR of 12.25% with insecticide poisoning. In multivariate analysis, Glasgow coma scale (GCS) score at admission is the only parameter showing a statistically significant association with mortality (adjusted odds-ratio 0.271(0.2-0.38, p-value < 0.01). Conclusion: Acute poisoning primarily affects the young and economically productive population. In the south Indian population, pesticides are still the major contributor though corrosives are a major contributor among children. Mortality is still significant, and GCS status admission is the only predictor of mortality. How to cite this article: Krishnasamy N, Narmadhalakshmi R, Parameshwari P, Jayalakshmi R, Lokesh R, Jayanthi R, et al. Determinants of Poison-related Mortality in Tertiary Care Hospital, South India. Indian J Crit Care Med 2024;28(4):329-335.

Chemical Behavior and Local Structure of the Ruddlesden-Popper and Dion-Jacobson Alloyed Pb/Sn Bromide 2D Perovskites.

The alloyed lead/tin (Pb/Sn) halide perovskites have gained significant attention in the development of tandem solar cells and other optoelectronic devices due to their widely tunable absorption edge. To gain a better understanding of the intriguing properties of Pb/Sn perovskites, such as their anomalous bandgap's dependence on stoichiometry, it is important to deepen the understanding of their chemical behavior and local structure. Herein, we investigate a series of two-dimensional Ruddlesden-Popper (RP) and Dion-Jacobson (DJ) phase alloyed Pb/Sn bromide perovskites using butylammonium (BA) and 3-(aminomethyl)pyridinium (3AMPY) as the spacer cations: (BA)2(MA)n-1PbxSnn-xBr3n+1 (n = 1-3) and (3AMPY)(MA)n-1PbxSnn-xBr3n+1 (n = 1-3) through a solution-based approach. Our results show that the ratio and site preference of Pb/Sn atoms are influenced by the layer thickness (n) and spacer cations (A'), as determined by single-crystal X-ray diffraction. Solid-state 1H, 119Sn, and 207Pb NMR spectroscopy analysis shows that the Pb atoms prefer the outer layers in n = 3 members: (BA)2(MA)PbxSnn-xBr10 and (3AMPY)(MA)PbxSnn-xBr10. Layered 2D DJ alloyed Pb/Sn bromide perovskites (3AMPY)(MA)n-1PbxSnn-xBr3n+1 (n = 1-3) demonstrate much narrower optical band gaps, lower energy PL emission peaks, and longer carrier lifetimes compared to those of RP analogs. Density functional theory calculations suggest that Pb-rich alloys (Pb:Sn ∼4:1) for n = 1 compounds are thermodynamically favored over 50:50 (Pb:Sn ∼1:1) compositions. From grazing-incidence wide-angle X-ray scattering (GIWAXS), we see that films in the RP phase orient parallel to the substrate, whereas for DJ cases, random orientations are observed relative to the substrate.

Hepatopulmonary syndrome is associated with low sphingosine-1-phosphate levels and can be ameliorated by the functional agonist fingolimod.

BACKGROUND & AIMS: Hepatopulmonary syndrome (HPS) is characterised by a defect in arterial oxygenation induced by pulmonary vascular dilatation in patients with liver disease. Fingolimod, a sphingosine-1-phosphate (S1P) receptor modulator, suppresses vasodilation by reducing nitric oxide (NO) production. We investigated the role of S1P in patients with HPS and the role of fingolimod as a therapeutic option in an experimental model of HPS. METHODS: Patients with cirrhosis with HPS (n = 44) and without HPS (n = 89) and 25 healthy controls were studied. Plasma levels of S1P, NO, and markers of systemic inflammation were studied. In a murine model of common bile duct ligation (CBDL), variations in pulmonary vasculature, arterial oxygenation, liver fibrosis, and inflammation were estimated before and after administration of S1P and fingolimod. RESULTS: Log of plasma S1P levels was significantly lower in patients with HPS than in those without HPS (3.1 ± 1.4 vs. 4.6 ± 0.2; p <0.001) and more so in severe intrapulmonary shunting than in mild and moderate intrapulmonary shunting (p <0.001). Plasma tumour necrosis factor-α (76.5 [30.3-91.6] vs. 52.9 [25.2-82.8]; p = 0.02) and NO (152.9 ± 41.2 vs. 79.2 ± 29.2; p = 0.001) levels were higher in patients with HPS than in those without HPS. An increase in Th17 (p <0.001) and T regulatory cells (p <0.001) was observed; the latter inversely correlated with plasma S1P levels. In the CBDL HPS model, fingolimod restored pulmonary vascular injury by increasing the arterial blood gas exchange and reducing systemic and pulmonary inflammation, resulting in improved survival (p = 0.02). Compared with vehicle treatment, fingolimod reduced portal pressure (p <0.05) and hepatic fibrosis and improved hepatocyte proliferation. It also induced apoptotic death in hepatic stellate cells and reduced collagen formation. CONCLUSIONS: Plasma S1P levels are low in patients with HPS and even more so in severe cases. Fingolimod, by improving pulmonary vascular tone and oxygenation, improves survival in a murine CBDL HPS model. IMPACT AND IMPLICATIONS: A low level of plasma sphingosine-1-phosphate (S1P) is associated with severe pulmonary vascular shunting, and hence, it can serve as a marker of disease severity in patients with hepatopulmonary syndrome (HPS). Fingolimod, a functional agonist of S1P, reduces hepatic inflammation, improves vascular tone, and thus retards the progression of fibrosis in a preclinical animal model of HPS. Fingolimod is being proposed as a potential novel therapy for management of patients with HPS.

Boron Adsorption Kinetics of Microcrystalline Cellulose and Polymer Resin.

Tailoring boron-polysaccharide interactions is an important strategy for developing functional soft materials such as hydrogels, fire retardants, and sorbents for environmental remediation, for example, using lignocellulosic biomass. For such applications to be realized, it is paramount to understand the adsorption kinetics of borate anions on cellulose and their local structures. Here, the kinetic aspects of boron adsorption by microcrystalline cellulose, lignin, and polymeric resin are investigated and compared. Borate anions interact with the vicinal diols in the glucopyranoside moieties of cellulose to yield chemisorbed boron chelate complexes. In contrast to cellulose, technical lignin contains fewer cis-vicinal diols, and it does not have a tendency to form such chelate complexes upon treatment with the aqueous boric acid solution. The formation kinetics and stability of these chelate complexes strongly depend on nanoscale structures, as well as reaction conditions such as pH and concentration of the sorbate and sorbent. Specifically, insights into the distinct boron adsorption sites were obtained by solid-state one-dimensional (1D) 11B magic-angle spinning NMR and the local structures and intermolecular interactions in the vicinities of boron chelate complexes are elucidated by analyzing two-dimensional (2D) 1H-13C and 11B-1H heteronuclear correlation NMR spectra. The total boron adsorption capacity of cellulose is estimated to be in the 1.3-3.0 mg range per gram of sorbent, which is lower than the boron adsorption capacity of a polystyrene-based resin, ∼17.2 mg of boron per gram of Amberlite IRA 743. Our study demonstrates that the local backbone and side chain flexibility as well as the structures of polyol groups play a significant role in determining the kinetic and thermodynamic stability of chelate complexes, yielding to different boron adsorption capabilities of lignocellulosic polymers.

Combined computational modeling and experimental analysis integrating chemical and mechanical signals suggests possible mechanism of shoot meristem maintenance.

Stem cell maintenance in multilayered shoot apical meristems (SAMs) of plants requires strict regulation of cell growth and division. Exactly how the complex milieu of chemical and mechanical signals interact in the central region of the SAM to regulate cell division plane orientation is not well understood. In this paper, simulations using a newly developed multiscale computational model are combined with experimental studies to suggest and test three hypothesized mechanisms for the regulation of cell division plane orientation and the direction of anisotropic cell expansion in the corpus. Simulations predict that in the Apical corpus, WUSCHEL and cytokinin regulate the direction of anisotropic cell expansion, and cells divide according to tensile stress on the cell wall. In the Basal corpus, model simulations suggest dual roles for WUSCHEL and cytokinin in regulating both the direction of anisotropic cell expansion and cell division plane orientation. Simulation results are followed by a detailed analysis of changes in cell characteristics upon manipulation of WUSCHEL and cytokinin in experiments that support model predictions. Moreover, simulations predict that this layer-specific mechanism maintains both the experimentally observed shape and structure of the SAM as well as the distribution of WUSCHEL in the tissue. This provides an additional link between the roles of WUSCHEL, cytokinin, and mechanical stress in regulating SAM growth and proper stem cell maintenance in the SAM.

Jamun Seed-Derived Nitrogen-Doped Carbon Dots: A Novel Microwave-Assisted Synthesis for Ultra-Bright Fluorescence and Mn7+ Detection.

For the synthesis of heteroatom-doped carbon nanostructures, biomass is considered as a promising option. Utilizing the microwave-assisted method, we have demonstrated an easy and straightforward one-pot synthesis of nitrogen-doped luminous carbon dots (NCDs) from jamun seed powder and guanidine hydrochloride. Structural and morphological analyses were performed using various analytical techniques. Under ultraviolet light of 315 nm, NCDs emit a bright blue fluorescence, possess a high quantum yield of 26.90%, exhibit strong water dispersion, and demonstrated excellent stability. The average particle size of the NCDs was found to be 7.5±1.2 nm, with a spherical shape. NCDs exhibit high selectivity and sensitivity in fluorescence quenching when exposed to Mn7+ ions. Over a concentration range of 2-30 µM, the fluorescence response (F0/F) shows a linear relationship with Mn7+ concentration, with a detection limit of 0.81 µM. The probe exhibited negligible interference and proved to be effective in accurately quantifying Mn7+ in spiked real-water samples.

Hydrothermal Fabrication of Efficient Binary Pd/Ag2S Heterojunction Composites: Synthesis, Characterization, and Fluorometric Selective Sensing of Organophosphate Pesticides.

Although many plasmonic nanosensors have been established for the detection of analytes, few of them are feasible for analyzing natural samples with very complex matrices because of insufficient method selectivity. To address this challenge, we propose an epitaxial and lattice-mismatch approach to the synthesis of a unique Pd/Ag2S nanostructure, which consists of a Pd segment with excellent plasmonic characteristics, and a highly stable Ag2S portion with minimum solubility product (Ksp(Ag2S) = 6.3 × 10- 50). Hence, Ag2S nanoparticles (NPs) and optimized (10.05 mmol/L) Pd/Ag2S composite were prepared using a hydrothermal method. The fabricated samples were characterized using different tools including UV-vis DRS, PL, powder XRD, TEM, and BET surface area measurements. Furthermore, the fluorometric sensing performance of the Ag2S and Pd/Ag2S samples was examined in the detection of organophosphate pesticides such as MLT, PRT, DZN, FNT, DCL, MCP, and CPS pesticides at room temperature. The quantitative detection of MLT, PRT, DZN, FNT, DCL, MCP, and CPS pesticides was achieved based on the Pd/Ag2S composite and organophosphate group-specific interaction. The optimized sensor exhibited a lower limit of detection (3.08 µM), excellent reproducibility, selectivity, and stability with an enhanced sensitivity of - 207.1 µA/µM cm2 (R2 = 0.98) in the range of 10 µM-100 µM for the detection of CPS pesticide. In addition, the fluorometric sensor has excellent selectivity, reproducibility, and stability, providing a feasible method for not only the detection of CPS pesticides but also other analytes in the future.

Synthesis and cytotoxicity evaluation of DNA-interactive ß-carboline indolyl-3-glyoxamide derivatives: Topo-II inhibition and in silico modelling studies.

In a quest for effective cancer targeted drug therapy, a series of new ß-carboline tethered indole-3-glyoxylamide derivatives, conjoining salient pharmacophoric properties with prominent cytotoxicity, were synthesized. The in vitro cytotoxic ability of the compounds was established, and many of the compounds exhibited remarkable cytotoxicity (IC50 < 10 µM) on human cancer cell lines like HCT116, A549, SK-MEL-28, and MCF7. Precisely, compound 12x expressed the best cytotoxic potential against melanoma cancer cell line (SK-MEL-28) with an IC50 value of 4.37 µM. In addition, cytotoxicity evaluation against normal kidney cell line (NRK52E) entrenched the cytospecificity and selectivity index of 12x. The traditional apoptosis assays advised morphological and nuclear alterations such as apoptotic body formation, condensed/horseshoe-shaped/fragmented nuclei, and generation of ROS. The flow cytometric analysis revealed significant early and slight late-stage induction of apoptosis. The target-based physiochemical assays indicated the ability of compound 12x to bind with DNA and inhibition of Topoisomerase II. Moreover, molecular modeling studies affirm the excellent DNA intercalation potential and stabilized interactions of 12x with DNA base pairs. In silico prediction of physicochemical parameters revealed the promising drug-like properties of the synthesized derivatives.