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BCL6 translocation is one of the most common chromosomal translocations in cancer and results in its enhanced expression in germinal center B cells. It involves the fusion of BCL6 with any of its twenty-six Ig and non-Ig translocation partners associated with diffuse large B cell lymphoma (DLBCL). Despite being discovered long back, the mechanism of BCL6 fragility is largely unknown. Analysis of the translocation breakpoints in 5' UTR of BCL6 reveals the clustering of most of the breakpoints around a region termed Cluster II. In silico analysis of the breakpoint cluster sequence identified sequence motifs that could potentially fold into non-B DNA. Results revealed that the Cluster II sequence folded into overlapping hairpin structures and identified sequences that undergo base pairing at the stem region. Further, the formation of cruciform DNA blocked DNA replication. The sodium bisulfite modification assay revealed the single-strandedness of the region corresponding to hairpin DNA in both strands of the genome. Further, we report the formation of intramolecular parallel G4 and triplex DNA, at Cluster II. Taken together, our studies reveal that multiple non-canonical DNA structures exist at the BCL6 cluster II breakpoint region and contribute to the fragility leading to BCL6 translocation in DLBCL patients.
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Linfoma Difuso de Grandes Células B , Translocação Genética , Humanos , Translocação Genética/genética , Rearranjo Gênico , Linfoma Difuso de Grandes Células B/genética , Linfócitos B , Regiões 5' não Traduzidas , DNA , Proteínas Proto-Oncogênicas c-bcl-6/genéticaRESUMO
t(8;14) translocation is the hallmark of Burkitt's lymphoma and results in c-MYC deregulation. During the translocation, c-MYC gene on chromosome 8 gets juxtaposed to the Ig switch regions on chromosome 14. Although the promoter of c-MYC has been investigated for its mechanism of fragility, little is known about other c-MYC breakpoint regions. We have analyzed the translocation break points at the exon 1/intron 1 of c-MYC locus from patients with Burkitt's lymphoma. Results showed that the breakpoint region, when present on a plasmid, could fold into an R-loop confirmation in a transcription-dependent manner. Sodium bisulfite modification assay revealed significant single-strandedness on chromosomal DNA of Burkitt's lymphoma cell line, Raji, and normal lymphocytes, revealing distinct R-loops covering up to 100 bp region. Besides, ChIP-DRIP analysis reveals that the R-loop antibody can bind to the breakpoint region. Further, we show the formation of stable parallel intramolecular G-quadruplex on non-template strand of the genome. Finally, incubation of purified AID in vitro or overexpression of AID within the cells led to enhanced mutation frequency at the c-MYC breakpoint region. Interestingly, anti-γH2AX can bind to DSBs generated at the c-MYC breakpoint region within the cells. The formation of R-loop and G-quadruplex was found to be mutually exclusive. Therefore, our results suggest that AID can bind to the single-stranded region of the R-loop and G4 DNA, leading to the deamination of cytosines to uracil and induction of DNA breaks in one of the DNA strands, leading to double-strand break, which could culminate in t(8;14) chromosomal translocation.
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Linfoma de Burkitt , Quadruplex G , Humanos , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , DNA , Genes myc , Estruturas R-Loop , Translocação GenéticaRESUMO
Dysphagia is a significant health concern especially amongst the old age population. It is an ailment brought on by the weakening of the swallowing muscles. To reduce the risk of choking in dysphagia patients, the food is usually diluted to suit their swallowing ability. But dilution results in reducing the nutritional density of the foods thus causing undernutrition and malnutrition in patients. In this study, functional liquid diets were formulated under International Dysphagia Diet Standardization Initiative (IDDSI) levels 0-2. The developed diets were analysed for their proximate composition, colour, antioxidant and sensory properties. Antioxidant activities were determined using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and total phenolic content (TPC) methods. The highest ABTS+ value was observed in pumpkin puree (level-2) i.e. 98.59%. Black carrot juice (level-1) showed the highest DPPH free radical scavenging activity and FRAP value viz. 88.43% and 689.33 µM TE/g, respectively. Electromyography (EMG) is an upcoming technique of food texture evaluation which provides real-time information about food oral processing. In this study, an EMG was conducted to measure the myoelectrical activity of human suprahyoid and masseter muscles by placing electrodes on the skin's surface during the oral processing of liquid. The EMG parameters correlated significantly with viscosity, ease of swallowing and IDDSI levels of the formulated diets. Hence EMG can be used as a tool for design and development of textured-modified diets for dysphagia patients. The sensory scores of formulated diets in this study were high indicating that these liquid diets may be incorporated into the diet plans of dysphagia patients.
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Targeted cancer therapy aims to disrupt the functions of proteins that regulate cancer progression, mainly by using small molecule inhibitors (SMIs). SMIs exert their effect by modulating signalling pathways, organelle integrity, chromatin components, and several biosynthetic processes essential for cell division and survival. Antiapoptotic protein BCL2 is highly upregulated in many cancers compared with normal cells, making it an ideal target for cancer therapy. Around 75% of primary breast cancers overexpress BCL2, providing an opportunity to explore BCL2 inhibitors as a therapeutic option. Disarib is an SMI that has been developed as a selective BCL2 inhibitor. Disarib works by disrupting BCL2-BAK interaction and activating intrinsic apoptotic pathways in leukemic cells while sparing normal cells. We investigated the effects of Disarib, a BCL2 specific inhibitor, on breast cancer cells and xenografts. Cytotoxicity and fluorometric assays revealed that Disarib induced cell death by increasing reactive oxygen species and activating intrinsic apoptotic pathways in Triple-Negative Breast Cancer cells (MDA-MB-231 and MDA-MB-468). Disarib also affected the colony-forming properties of these cells. MDA-MB-231- and MDA-MB-468-derived xenografts showed a significant reduction in tumours upon Disarib treatment. Through the transcriptomics approach, we also explored the influence of BCL2 inhibitors on energy metabolism, mitochondrial dynamics, and epithelial-to-mesenchymal transition (EMT). Mitochondrial dynamics and glucose metabolism mainly regulate energy metabolism. The change in energetics regulates tumour growth through epithelial-mesenchymal transition, and angiogenesis. RNA sequencing (RNAseq) analysis revealed that BCL2 inhibitors ABT-199 and Disarib maintain Oxphos levels in MDA-MB-231. However, key glycolytic genes were significantly downregulated. Mitochondrial fission genes were seen to be downregulated both in RNAseq data and semi quantitative real time polymerase chain reaction (qRTPCR) in Disarib-treated TNBC cells and xenografts. Lastly, Disarib inhibited wound healing and epithelial-to-mesenchymal transition. This study showed that Disarib disrupts mitochondrial function, activates the intrinsic apoptotic pathway in breast cancer, and inhibits epithelial-to-mesenchymal transition both in vitro and in vivo. These findings highlight Disarib's potential as a multifaceted therapeutic strategy for patients with Triple-Negative Breast Cancer.
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Apoptose , Mitocôndrias , Proteínas Proto-Oncogênicas c-bcl-2 , Neoplasias de Mama Triplo Negativas , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/genética , Humanos , Animais , Apoptose/efeitos dos fármacos , Feminino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Camundongos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacosRESUMO
The anti-inflammatory and neuroprotective effects of short chain fatty acid (SCFA) butyrate have been explored in a wide array of neurological pathologies. It is a 4-carbon SCFA produced from the fermentation of dietary fibers by the gut-microbiota. As evident from previous literature, butyrate plays a wide array of functions in CNS and interestingly enhances the differentiation potential of Neural stem/Progenitor Cells (NSPCs). Japanese encephalitis virus (JEV) is a well-known member of the Flaviviridae family and has been shown to alter neural stem cell pool of the brain, causing devastating consequences. In this study, we administered sodium butyrate (NaB) post JEV infection in BALB/c mouse model to examine any possible amelioration of the viral infection in NSPCs. In addition, ex vivo neurospheres and in vitro model of NSPCs were also used to study the effect of sodium butyrate in JEV infection. As an unprecedented finding, butyrate treated infected animals presented early onset of symptoms, as compared to their respective JEV infected groups. Alongside, we observed an increased viral load in NSPCs isolated from these animals as well as in cell culture models upon sodium butyrate treatment. Cytometric bead array analysis also revealed an increase in inflammatory cytokines, particularly, MCP-1 and IL-6. Further, increased expression of the key members of the canonical NF-κB pathway, viz-a-viz p-NF-κB, p-Iκ-Bα and p-IKK was observed. Overall, the increased inflammation and cell death caused early symptom progression in NaB-treated JEV infected animal model, which is contradictory to the well documented protective nature of NaB and therefore a better understanding of SCFA-based modulation of the gut-brain axis in viral infections is required.
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Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Células-Tronco Neurais , Animais , Camundongos , Encefalite Japonesa/metabolismo , Encefalite Japonesa/patologia , Ácido Butírico/farmacologia , NF-kappa B , Células-Tronco Neurais/metabolismo , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Modelos TeóricosRESUMO
Despite several treatment options for blood cancer, mortality remains high due to relapse and the disease's aggressive nature. Elevated levels of HSP90, a molecular chaperone essential for protein folding, are associated with poor prognosis in leukemia and lymphoma. HSP90 as a target for chemotherapy has been met with limited success due to toxicity and induction of heat shock. This study tested the activity of an HSP90 inhibitor, SP11, against leukemic cells, mouse lymphoma allograft, and xenograft models. SP11 induced cytotoxicity in vitro in leukemic cell lines and induced cell death via apoptosis, with minimal effect on normal cells. SP11 induced cell death by altering the status of HSP90 client proteins both in vitro and in vivo. SP11 reduced the tumor burden in allograft and xenograft mouse models without apparent toxicity. The half-life of SP11 in the plasma was approximately 2 h. SP11 binding was observed at both the N-terminal and C-terminal domains of HSP90. C-terminal binding was more potent than N-terminal binding of HSP90 in silico and in vitro using isothermal calorimetry. SP11 bioavailability and minimal toxicity in vivo make it a potential candidate to be developed as a novel anticancer agent.
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Antineoplásicos , Cumarínicos , Humanos , Animais , Camundongos , Cumarínicos/farmacologia , Linhagem Celular Tumoral , Proteínas de Choque Térmico HSP90/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Dobramento de Proteína , ApoptoseRESUMO
Objective: To expand the measles and rubella laboratory network of India by integrating new laboratories. Methods: In collaboration with the World Health Organization (WHO), the Indian government developed a 10-step scheme to systematically expand the number of laboratories performing serological and molecular testing for measles and rubella. The Indian Council of Medical Research and WHO identified suitable laboratories based on their geographical location, willingness, preparedness, past performance and adherence to national quality control and quality assurance mechanisms. The 10-step scheme was initiated with training on measles and rubella diagnostic assays followed by testing of both measles and rubella serology and molecular unknown panels, cross-verification with reference laboratories and ended with WHO on-site accreditation. Findings: After extensive training, technical support, funding and monitoring, all six selected laboratories attained passing scores of 90.0% or more in serological and molecular proficiency testing of measles and rubella. Since 2018, the laboratories are a part of the measles and rubella network of India. Within 12 months of initiation of independent reporting, the six laboratories have tested 2287 serum samples and 701 throat or nasopharyngeal swabs or urine samples. Conclusion: The process led to strengthening and expansion of the network. This proficient laboratory network has helped India in scaling up serological and molecular testing of measles and rubella while ensuring high quality testing. The collaborative model developed by the Indian government with WHO can be implemented by other countries for expanding laboratory networks for surveillance of measles and rubella as well as other infectious diseases.
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Sarampo , Rubéola (Sarampo Alemão) , Saúde Global , Humanos , Índia , Laboratórios , Sarampo/diagnóstico , Sarampo/epidemiologia , Sarampo/prevenção & controle , Rubéola (Sarampo Alemão)/diagnóstico , Rubéola (Sarampo Alemão)/epidemiologia , Rubéola (Sarampo Alemão)/prevenção & controleRESUMO
Nonhomologous end joining (NHEJ), one of the major DNA double-strand break repair pathways, plays a significant role in cancer cell proliferation and resistance to radio and chemotherapeutic agents. Previously, we had described a small molecule inhibitor, SCR7, which inhibited NHEJ in a DNA Ligase IV dependent manner. Here, we report that SCR7 potentiates the effect of γ-radiation (IR) that induces DNA breaks as intermediates to eradicate cancer cells. Dose fractionation studies revealed that coadministration of SCR7 and IR (0.5 Gy) in mice Dalton's lymphoma (DLA) model led to a significant reduction in mice tumor cell proliferation, which was equivalent to that observed for 2 Gy dose when both solid and liquid tumor models were used. Besides, co-treatment with SCR7 and 1 Gy of IR further improved the efficacy. Notably, there was no significant change in blood parameters, kidney and liver functions upon combinatorial treatment of SCR7 and IR. Further, the co-treatment of SCR7 and IR resulted in a significant increase in unrepaired DSBs within cancer cells compared to either of the agent alone. Anatomy, histology, and other studies in tumor models confirmed the cumulative effects of both agents in activating apoptotic pathways to induce cytotoxicity by modulating DNA damage response and repair pathways. Thus, we report that SCR7 has the potential to reduce the side effects of radiotherapy by lowering its effective dose ex vivo and in mice tumor models, with implications in cancer therapy.
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Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , Reparo do DNA por Junção de Extremidades/efeitos da radiação , Pirimidinas/farmacologia , Radiação Ionizante , Radiossensibilizantes/farmacologia , Bases de Schiff/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos da radiação , DNA Ligase Dependente de ATP/metabolismo , Modelos Animais de Doenças , Humanos , Camundongos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The effect of ligand binding on the conformational transitions of the add A-riboswitch in cellular environments is investigated theoretically within the framework of the generalized Langevin equation combined with steered molecular dynamics simulations. Results for the transition path time distribution provide an estimate of the transit times, which are difficult to determine experimentally. The time for the conformational transitions of the riboswitch aptamer is longer for the ligand bound state as compared to that of the unbound one. The transition path time of the riboswitch follows a counterintuitive trend as it decreases with an increase in the barrier height. The mean transition path time of either transitions of the riboswitch in the ligand bound/unbound state increases with an increase in the complexity of the surrounding environment due to the caging effect. The results of the probability density function, transition path time distribution, and mean transition path time obtained from the theory qualitatively agree with those obtained from the simulations and with earlier experimental and theoretical studies.
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Adenosina Desaminase/química , Teoria da Densidade Funcional , Simulação de Dinâmica Molecular , Adenosina Desaminase/metabolismo , LigantesRESUMO
Biofilms play an important role in the antibiotic drug resistance, which is threatening public health globally. Almost, all microbes mimic multicellular lifestyle to form biofilm by undergoing phenotypic changes to adapt adverse environmental conditions. Many anti-biofilm agents have been experimentally validated to disrupt the biofilms during last three decades. To organize this data, we developed the 'aBiofilm' resource (http://bioinfo.imtech.res.in/manojk/abiofilm/) that harbors a database, a predictor, and the data visualization modules. The database contains biological, chemical, and structural details of 5027 anti-biofilm agents (1720 unique) reported from 1988-2017. These agents target over 140 organisms including Gram-negative, Gram-positive bacteria, and fungus. They are mainly chemicals, peptides, phages, secondary metabolites, antibodies, nanoparticles and extracts. They show the diverse mode of actions by attacking mainly signaling molecules, biofilm matrix, genes, extracellular polymeric substances, and many more. The QSAR based predictor identifies the anti-biofilm potential of an unknown chemical with an accuracy of â¼80.00%. The data visualization section summarized the biofilm stages targeted (Circos plot); interaction maps (Cytoscape) and chemicals diversification (CheS-Mapper) of the agents. This comprehensive platform would help the researchers to understand the multilevel communication in the microbial consortium. It may aid in developing anti-biofilm therapeutics to deal with antibiotic drug resistance menace.
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Anti-Infecciosos , Biofilmes/efeitos dos fármacos , Bases de Dados de Compostos Químicos , Descoberta de Drogas , Resistência Microbiana a Medicamentos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Bactérias/efeitos dos fármacos , Curadoria de Dados , Apresentação de Dados , Sistemas de Liberação de Medicamentos , Fungos/efeitos dos fármacos , Armazenamento e Recuperação da Informação , Microbiota/efeitos dos fármacos , Relação Quantitativa Estrutura-Atividade , Percepção de QuorumRESUMO
Efficient DNA repair is indispensable for maintaining genomic integrity in humans. Cancer associated deletions and mutations are mainly due to misrepaired DNA double-strand breaks (DSBs). Classical nonhomologous end joining (c-NHEJ) and homologous recombination (HR) are two major DSB repair pathways in humans. An error prone, alternative NHEJ pathway that utilizes microhomology was also reported in cancer cells and to a lesser extent in normal cells. In the present study, we evaluated the efficiency of various DSB repair pathways in the most common lymphoma, the diffuse large B cell lymphoma (DLBCL). Here we show that DNA repair through c-NHEJ pathway is limited in SUDHL8, a cell line derived from a DLBCL patient. Unlike c-NHEJ, microhomology mediated end joining (MMEJ) was predominant at physiological temperature. Consistent with the observation, expression level of repair proteins such as LIGASE I, LIGASE III, PARP1, CtIP, and MRE11 was higher in DLBCL cells when compared to c-NHEJ proteins. Further, inhibition of LIGASE I or MRE11, led to reduction in the efficiency of MMEJ in DLBCL cells. Besides, HR-mediated DSB repair occurring through gene conversion was observed. Thus, our results reveal the predominance of MMEJ over c-NHEJ in repairing DSBs in DLBCL cells, while error-free repair through HR was also evident.
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Reparo do DNA , Redes Reguladoras de Genes , Linfoma Difuso de Grandes Células B/metabolismo , Regulação para Cima , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Endodesoxirribonucleases , Regulação Neoplásica da Expressão Gênica , Humanos , Linfoma Difuso de Grandes Células B/genética , Proteína Homóloga a MRE11/genética , Proteína Homóloga a MRE11/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismoRESUMO
A rapid, efficient, and metal-free Lewis acid-mediated methodology has been developed for the site-selective synthesis of unsymmetrical oxygenated biaryls. This simple and efficient methodology furnished highly oxygenated and functionalized unsymmetrical biaryls in good to excellent yields by the direct oxidative coupling of electron-rich arenes to the α-position of carbonyl functionality of in situ generated masked benzoquinones.
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Japanese encephalitis virus (JEV) is one of the major neurotropic viral infections that is known to dysregulate the homeostasis of neural stem/progenitor cells (NSPCs) and depletes the stem cell pool. NSPCs are multipotent stem cell population of the central nervous system (CNS) which are known to play an important role in the repair of the CNS during insults/injury caused by several factors such as ischemia, neurological disorders, CNS infections, and so on. Viruses have evolved to utilize host factors for their own benefit and during JEV infection, host factors, including the non-coding RNAs such as miRNAs, are reported to be affected, thereby cellular processes regulated by the miRNAs exhibit perturbed functionality. Previous studies from our laboratory have demonstrated the role of JEV infection in dysregulating the function of neural stem cells (NSCs) by altering the cell fate and depleting the stem cell pool leading to a decline in stem cell function in CNS repair mechanism post-infection. JEV-induced alteration in miRNA expression in the NSCs is one of the major interest to us. In prior studies, we have observed an altered expression pattern of certain miRNAs following JEV infection. In this study, we have validated the role of JEV infection in NSCs in altering the expression of miR-9-5p, which is a known regulator of neurogenesis in NSCs. Furthermore, we have validated the interaction of this miRNA with its target, Onecut2 (OC2), in primary NSCs utilizing miRNA mimic and inhibitor transfection experiments. Our findings indicate a possible role of JEV mediated dysregulated interaction between miR-9-5p and its putative target OC2 in NSPCs. IMPORTANCE: MicroRNAs have emerged as key disease pathogenic markers and potential therapeutic targets. In this study, we solidify this concept by studying a key miRNA, miR-9-5p, in Japanese encephalitis virus infection of neural stem/progenitor cells. miRNA target Onecut2 has a possible role in stem cell pool biology. Here, we show a possible mechanistic axis worth investing in neurotropic viral biology.
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Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , MicroRNAs , Células-Tronco Neurais , Humanos , Vírus da Encefalite Japonesa (Espécie)/genética , Vírus da Encefalite Japonesa (Espécie)/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Encefalite Japonesa/genética , Encefalite Japonesa/patologia , Diferenciação CelularRESUMO
INTRODUCTION: Telehealth has emerged as a promising supplementary modality in prenatal care. However, its impact on patient-provider communication (PPC), especially among pregnant women from underserved settings, requires comprehensive evaluation. This study examined the factors associated with the quality of patient-provider communication during the COVID-19 pandemic among pregnant telehealth users and non-users. METHODS: Using a cross-sectional study design, 242 women were surveyed (response rate = 23%) regarding their experience with telehealth, quality of PPC, and experiences of discrimination during prenatal care. Multiple regression models were used to identify the factors associated with the quality of PPC during the COVID-19 pandemic. A sub-group analysis explored the factors associated with the quality of PPC separately among telehealth users and non-users. RESULTS: The majority of the participants were on Medicaid (95%) and self-identified as Black/African American (57.3%). Regression analyses revealed a negative relationship between telehealth use during pregnancy and the quality of PPC (ß = -1.13, P = 0.002). Irrespective of the telehealth use, the experience of discrimination was associated with poor quality of PPC among users (ß = -3.47, P = .02) and non-users (ß = -.78, P = .03), while adjusting for sociodemographic factors and social support during pregnancy. DISCUSSION: While telehealth offers advantages like convenience, increased accessibility, and continuity of care, challenges in establishing effective PPC in virtual settings have emerged that emphasize the necessity for comprehensive provider training extending beyond technical competencies. The persistent issue of perceived discrimination, impacting PPC across both groups, underscores the necessity to rethink existing strategies of mandatory training to increase providers' knowledge.
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BACKGROUND: Heterocyclic-based drugs have strong bioactivities, are active pharmacophores, and are used to design several antibacterial drugs. Due to the diverse biodynamic properties of well-known heterocyclic cores, such as quinoline, indole, and its derivatives, they have a special place in the chemistry of nitrogen-containing heterocyclic molecules. OBJECTIVES: The objective of this study is to analyze the interaction of several heterocyclic molecules using molecular docking and machine learning approaches to find out the possible antibacterial drugs. METHODS: The molecular docking analysis of heterocyclic-based analogues against the sarcin-Ricin Loop RNA from E. coli with a C2667-2'-OCF3 modification (PDB ID: 6ZYB) is discussed. RESULTS: Many heterocyclic-based derivatives show several residual interaction, affinity, and hydrogen bonding with sarcin-Ricin Loop RNA from E. coli with a C2667-2'-OCF3 alteration which are identified by the investigation of in silico molecular docking analysis of such heterocyclic derivatives. CONCLUSION: The dataset from the molecular docking study was used for additional optimum analysis, and the molecular descriptors were classified using a variety of machine learning classifiers, including the GB Classifier, CB Classifier, RF Classifier, SV Classifier, KNN Classifier, and Voting Classifier. The research presented here showed that heterocyclic derivatives may operate as potent antibacterial agents when combined with other compounds to produce highly efficient antibacterial agents.
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Antibacterianos , Escherichia coli , Aprendizado de Máquina , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Simulação de Acoplamento Molecular , RNA Bacteriano/química , RNA Bacteriano/metabolismoRESUMO
Introduction: The cycles of demineralization and remineralization result in a dynamic process of caries development. Caries are prevented by the shift in the balance from demineralization to remineralization at the tooth-oral fluid interface with the help of salivary fluoride levels (in parts per million). The advantages of fluoride varnish application over other substitutes like dentifrices, mouthrinses, gels, or foams are that varnishes are well tolerated by infants, young children, or children with special healthcare needs and have prolonged therapeutic effects. This study was formulated to evaluate and compare the longevity of fluoride release from different fluoride varnishes, namely Fluor Protector, Enamelast, and Enamel Pro varnish. Aim: To evaluate and compare the longevity of fluoride release from three different fluoride varnishes. Materials and methods: The study samples comprised 72 healthy permanent maxillary anterior teeth. The teeth were divided into four groups, with eighteen teeth in each group. The surfaces of all teeth were then covered by different colored nail varnish according to the respective group, except for a 3 × 3 mm window on the facial (labial) surface of the crown, where the test materials were applied according to their respective group. In group I, Fluor Protector varnish; in group II, Enamelast varnish; and in group III, Enamel Pro varnish was applied. Group IV was the control group; hence, no test material was applied. All specimens were then stored in plastic containers with a pH of 7.2 in artificial saliva at room temperature. The specimens were transferred into new plastic containers after 1 day, containing fresh artificial saliva, and solutions from previous plastic containers were taken for fluoride analysis. This process was repeated sequentially to analyze the amount of fluoride released in ppm from the specimens at the end of 1, 3, and 6 months. Statistical analysis: Analysis was performed on Statistical Package for the Social Sciences (SPSS) software (Windows version 22.0). Results: Conventionally used 1.5% ammonium fluoride varnish, that is, Fluor Protector varnish, showed the least release of fluoride (0.03 ± 0.0 ppm), while resin carrier-based 5% sodium fluoride varnish, that is, Enamelast varnish showed a good amount of fluoride release for 6 months continuously, that is, (0.16 ± 0.06 ppm) at last follow-up. Enamel Pro varnish, which has 5% sodium fluoride with amorphous calcium phosphate (ACP) formula, was found to be the best varnish as it released the maximum amount of fluoride in ppm in artificial saliva for up to 3 months (0.32 ± 0.08) but less than Enamelast varnish only at 6 months follow-up that is 0.09 ± 0.03 ppm. Conclusion: The present study concludes that based on the amount of fluoride released for 6 months duration, Enamel Pro varnish, followed by Enamelast varnish and Fluor Protector varnish, are advisable to apply for caries prevention. How to cite this article: Singh V, Naik S, Vashisth P, et al. Comparative Evaluation of Longevity of Fluoride Release from Three Different Fluoride Varnishes: An Observational Study. Int J Clin Pediatr Dent 2024;17(3):341-345.
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The main protease (MPro) of SARS-CoV-2, the causative agent of COVID-19, is a pivotal nonstructural protein critical for viral replication and pathogenesis. Its protease function relies on three active site pockets for substrate recognition and a catalytic cysteine for enzymatic activity. To develop potential SARS-CoV-2 antivirals, we successfully synthesized a diverse range of azapeptide inhibitors with various covalent warheads to target MPro's catalytic cysteine. Our characterization identified potent MPro inhibitors, including MPI89 that features an aza-2,2-dichloroacetyl warhead with a remarkable EC50 value of 10 nM against SARS-CoV-2 infection in ACE2+ A549 cells and a selective index of 875. MPI89 is also remarkably selective and shows no potency against SARS-CoV-2 papain-like protease and several human proteases. Crystallography analyses demonstrated that these inhibitors covalently engaged the catalytic cysteine and used the aza-amide carbonyl oxygen to bind to the oxyanion hole. MPI89 stands as one of the most potent MPro inhibitors, suggesting the potential for further exploration of azapeptides and the aza-2,2-dichloroacetyl warhead for developing effective therapeutics against COVID-19.
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COVID-19 , Proteases 3C de Coronavírus , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Cisteína , Cisteína Endopeptidases/metabolismo , Proteínas não Estruturais Virais , Inibidores de Proteases/farmacologia , Antivirais/farmacologiaRESUMO
Quinoline-based molecules are major constituents in natural products, active pharmacophores, and have excellent biological activities. Using 2H-thiopyrano[2,3-b]quinoline derivatives and CB1a protein (PDB ID: 2IGR), the molecular docking study has been revealed in this article. The study of in silico molecular docking analysis of such derivatives to determine the binding affinity, residual interaction, and hydrogen bonding of several 2H-thiopyrano[2,3-b]quinolines against CB1a is reported here. The current work demonstrated that 2H-thiopyrano[2,3-b]quinoline derivatives could be effective antitumor agents to produce potent anticancer medicines in the near future.
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Quinoline derivatives are an important class of heterocyclic compounds and possess various applications in synthetic organic chemistry, medicinal chemistry, material chemistry and natural product chemistry. This review article describes the different quinoline derivatives having antimalarial, analgesic, anti-inflammatory, antineoplastic, antibacterial, antifungal, antiviral, anthelmintic, antiprotozoal, cardiovascular, CNS and other useful bioactivities. We have delineated the general synthetic routes for the synthesis of many bioactive quinoline based heterocycles. In addition to this, we have also discussed the crucial synthetic routes as well as their mechanistic paths for the formation of bioactive quinoline derivatives. The study shows that substitution at the 4 and 8- position of quinoline is more crucial for bioactivity as compared to other positions.
Assuntos
Anti-Infecciosos Locais , Anti-Infecciosos , Antiprotozoários , Hidroxiquinolinas , Quinolinas , Anti-Infecciosos/farmacologia , Analgésicos , Anti-InflamatóriosRESUMO
Quinoline and its analogues are found in various natural products, many of which are active pharmacophores with significant bioactivities. This article discussed the plethora of quinoline derivatives and their analogues that have anti-cancer properties. The review will be helpful for the scientific community since several possible anticancer drugs based on quinolines are discussed here. In addition to this, the synthetic aspect of many such quinoline derivatives showing anti-cancer activities is also revealed in this article. These quinoline-based anti-oncogenic molecules can be synthesized using several acids, bases, and azides or with the help of reagents like Jone's reagent and Lawesson's reagent.