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1.
Blood ; 142(1): 90-105, 2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37146239

RESUMO

RNA-binding proteins (RBPs) form a large and diverse class of factors, many members of which are overexpressed in hematologic malignancies. RBPs participate in various processes of messenger RNA (mRNA) metabolism and prevent harmful DNA:RNA hybrids or R-loops. Here, we report that PIWIL4, a germ stem cell-associated RBP belonging to the RNase H-like superfamily, is overexpressed in patients with acute myeloid leukemia (AML) and is essential for leukemic stem cell function and AML growth, but dispensable for healthy human hematopoietic stem cells. In AML cells, PIWIL4 binds to a small number of known piwi-interacting RNA. Instead, it largely interacts with mRNA annotated to protein-coding genic regions and enhancers that are enriched for genes associated with cancer and human myeloid progenitor gene signatures. PIWIL4 depletion in AML cells downregulates the human myeloid progenitor signature and leukemia stem cell (LSC)-associated genes and upregulates DNA damage signaling. We demonstrate that PIWIL4 is an R-loop resolving enzyme that prevents R-loop accumulation on a subset of AML and LSC-associated genes and maintains their expression. It also prevents DNA damage, replication stress, and activation of the ATR pathway in AML cells. PIWIL4 depletion potentiates sensitivity to pharmacological inhibition of the ATR pathway and creates a pharmacologically actionable dependency in AML cells.


Assuntos
Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/patologia , Células-Tronco Hematopoéticas/metabolismo , Proliferação de Células , Genômica , RNA Mensageiro/metabolismo , Células-Tronco Neoplásicas/patologia
2.
Inorg Chem ; 63(16): 7146-7160, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38592926

RESUMO

The crystal structure of the metal-organic framework (MOF), {Mn2(1,4-bdc)2(DMF)2}n (1) (1,4-bdcH2, 1,4-benzenedicarboxylic acid; DMF, N,N-dimethylformamide), is known for a long time; however, its desolvated structure, {Mn2(1,4-bdc)2}n (1'), is not yet known. The first-principles-based computational simulation was used to unveil the structure of 1' that shows the expansion in the framework, leading to pore opening after the removal of coordinated DMF molecules. We have used 1' that contains open metal sites (OMSs) in the structure in cyanosilylation and CO2 cycloaddition reactions and recorded complete conversions in a solventless setup. The pore opening in 1' allows the facile diffusion of small aldehyde molecules into the channels, leading to complete conversion. The reactions with larger aldehydes, 2-naphthaldehyde and 9-anthracenecarboxaldehyde, also show 99.9% conversions, which are the highest reported until date in solventless conditions. The in silico simulations illustrate that larger aldehydes interact with Mn(II) OMSs on the surfaces, enabling a closer interaction and facilitating complete conversions. The catalyst shows high recyclability, exhibiting 99.9% conversions in the successive reaction cycles with negligible change in the structure. Our investigations illustrate that the catalyst 1' is economical, efficient, and robust and allows reactions in a solventless greener setup, and therefore the catalysis with 1' can be regarded as "green catalysis".

3.
Org Biomol Chem ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39054964

RESUMO

An unprecedented radical-promoted strategy involving a domino alkylation/intramolecular C5-annulation of N-acryloyl-4-amino coumarin has been devised for the assembly of 4,5-fused coumarin scaffolds. This protocol employs silver-catalyzed oxidative decarboxylation for the generation of alkyl radicals from carboxylic acids, which were used as radical precursors. This method has also been extended to a diverse range of carbon-centered radicals generated from 2-oxo acids, a 1,3-dicarbonyl compound, isopropanol and acetone.

4.
Int Microbiol ; 26(2): 281-294, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36478539

RESUMO

The solfataric soil sediments of the hot springs of Sikkim located at Yume Samdung and Lachen valley were studied for deciphering the bacterial diversity. The main aim here is to present a comparative study and generate a baseline data on the post-monsoon seasonal variation for the months of October and December, analyzed through 16S rRNA V3-V4 amplicon sequencing. The results have shown that there is not much variation at phylum level in the month of October in all the three hot springs such as New Yume Samdung (NYS), Old Yume Samdung (OYS), and Tarum (TAR) hot spring. The abundant phyla mainly present were Firmicutes, followed by Proteobacteria, Actinobacteria, and Bacteroidetes. Similarly, in the month of December, Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes were prevalent; however, the percent relative abundance of these phyla in the month of December is relatively less. Besides this decrease in percent abundance, it was interestingly seen that relatively more phyla were found contributing towards the bacterial diversity in the month of December. Similar to phylum level, at genus level, there was not much variation seen among various prevalent genera of the three studied hot springs in both months. The major genera prevalent in both months among all the three hot springs were followed by Bacillus, Desulfotomaculum, Lactobacillus, and Paenibacillus. A similar trend was also seen at gene level that relative abundance of various genera was higher in the month of October but more genera were found to be contributing towards bacterial diversity in the month of December. Few distinct genera were found to be more abundant in the month of December such as Rhodopirellula and Blastopirellula. The results may conclude that there is not much variation in the abundance and type of bacterial communities during the post-monsoon season in the month of October and December. However, this may be assumed that there is the accumulation or increase in the bacterial communities during the winter (relatively higher temperature among hot springs) and may favor few mesophilic and more thermophilic communities as well.


Assuntos
Fontes Termais , Estações do Ano , Fontes Termais/microbiologia , Siquim , RNA Ribossômico 16S/genética , Solo , Filogenia , Bactérias/genética , Proteobactérias/genética , Firmicutes/genética
5.
J Org Chem ; 88(11): 7046-7057, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37170946

RESUMO

The reaction of alkynyl p-quinone methide (pQM) with keto-methylenes through a base-mediated tandem 1,6-addition/annulation sequence, [2 + 3] annulation, affording the furans is reported for the first time. A variety of functionalized furans, including fused derivatives, were obtained in good to excellent yields under mild reaction conditions. The efficacy of alkynyl pQMs is highlighted by extending their use to access isoxazoles, pyrazoles via [3 + 2] annulation, and pyridines through [3 + 3] annulation in the presence of different bis-nucleophiles.

6.
J Appl Microbiol ; 134(2)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36626778

RESUMO

AIMS: Probiotics are known to maintain intestinal homeostasis through the regulation of the immune response of the host. Hence, the role of histone modifications as epigenetic agents on immune modulations by potential probiotic bacteria has been investigated. METHODS AND RESULTS: Human colonic epithelial cells (Caco-2) pre-treated with class I histone deacetylase (HDAC) specific inhibitor, MS-275, were incubated either with potential probiotic bacteria (Limosilactobacillus fermentum MTCC 5898 and Lacticaseibacillus rhamnosus MTCC 5897) or Escherichia coli (ATCC 14948) as an inflammatory agent. Initially, transcriptional expression of potential immune-related genes (IL-6, IL-8, and hBD-2) was analyzed using RT-qPCR, and later H3 histone acetylation (H3Ac) at the promoter region of these genes was confirmed with a chromatin immunoprecipitation (ChIP) assay respectively. Potential probiotic L. fermentum (MTCC 5898) significantly suppressed (P < 0.05) the inhibitor-mediated elevated expression of immune-related genes while another strain L. rhamnosus (MTCC 5897), did not influence these gene expression results. In contrast, as an inflammatory agent, E. coli (ATCC 14948) synergistically augmented the expression of immune-related genes. Later, ChIP analysis confirmed the occurrence of H3 acetylation at these genes' promoter regions, which was directly related to the transcriptional activity of host epithelial cells stimulated by L. fermentum and E. coli, respectively. But in the case of L. rhamnosus, MTCC 5897, acetylation did not follow the transcription pattern and potentiated H3Ac on the promoter regions of these genes. CONCLUSIONS: Potential probiotics used in the study were found to regulate the immune response of host cells through histone acetylation in a strain-specific manner. SIGNIFICANCE AND IMPACT OF STUDY: Occurrence of probiotic-mediated regulation of immune genes by H3 acetylation in a strain-specific manner.


Assuntos
Histonas , Probióticos , Humanos , Histonas/genética , Histonas/metabolismo , Lactobacillus/genética , Lactobacillus/metabolismo , Células CACO-2 , Acetilação , Escherichia coli/genética , Escherichia coli/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Imunidade , Probióticos/farmacologia
7.
J Vector Borne Dis ; 60(2): 161-171, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37417165

RESUMO

BACKGROUND & OBJECTIVES: Dengue virus (DENV) is the causative agent of dengue fever (DF) and dengue hemorrhagic fever (DHF). It has four distinct serotypes (DENV-1, DENV-2, DENV-3, and DENV-4) based on their antigenic properties. Mostly, the immunogenic epitopes are present in the envelope (E) protein of the virus. Heparan sulfate (HS) acts as a receptor and interacts with the E protein of the virus thus facilitating the entry of dengue virus into human cells. This study focuses on epitope prediction on the E protein of the DENV serotype. The non-competitive inhibitors of HS were designed using bioinformatics. METHODS: In the present study, epitope prediction of the E protein of DENV serotypes was performed using the ABCpred server and IEDB analysis resource. The interactions of HS and viral E proteins (PDB ID: 3WE1 and PDB ID:1TG8) were evaluated through AutoDock. Subsequently, non-competitive inhibitors were designed to bind the E protein of DENV better than HS. All the docking results were validated by re-docking the ligand-receptor complexes and superimposing them onto their co-crystallized complexes using AutoDock and visualizing them in Discovery Studio. RESULTS: The result predicted B-cell and T-cell epitopes on the E protein of DENV serotypes. The designed HS ligand 1 (non-competitive inhibitor) demonstrated potential binding with the DENV E protein, thereby inhibiting HS-E protein binding. The re-docked complexes were superimposed entirely onto the native co-crystallized complexes (low root mean square deviation values), which validates the docking protocols. INTERPRETATION & CONCLUSION: The identified B-cell and T-cell epitopes of the E protein and non-competitive inhibitors of HS (ligand 1) could be used in the designing of potential drug candidates against the dengue virus.


Assuntos
Vírus da Dengue , Dengue , Humanos , Anticorpos Antivirais , Epitopos de Linfócito T , Ligantes , Proteínas do Envelope Viral
8.
Arch Microbiol ; 204(7): 411, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729284

RESUMO

The epigenome of an organism is as important as the genome for the normal development and functioning of an individual. The human epigenome can be affected by various environmental factors including nutrients, microbiota and probiotics through epigenetic modifiers and mediates various health-promoting effects. The present study was aimed to explore the temporal changes in DNA and histone modifiers (DNMT1, TET2, p300, HDAC1, KMT2A, KDM5B, EzH2 and JMJD3) in intestinal epithelial cells (Caco-2) by probiotic lactobacilli (Limosilactobacillus fermentum MTCC 5898 and Lacticaseibacillus rhamnosus MTCC 5897) in comparison to opportunistic commensal pathogen Escherichia coli (ATCC 14849). Cells were treated separately with probiotic strains and E. coli for different durations and temporal changes in gene expression among DNA and histone modifiers were measured. Time-dependent studies showed that L. fermentum enhanced the transcription of epigenetic modifiers at 12 h of treatment (P < 0.05) contrary to E. coli which reduced the expression of these genes during the same duration of treatment. On the other hand, probiotic L. rhamnosus was not able to induce any significant changes in gene expression of these modifiers. Furthermore, during the exclusion of E. coli by L. fermentum, the probiotic was found to resist the changes made by E. coli in the transcription of some of the epigenetic modifiers. Thus, it is concluded that the probiotics modulated the mRNA expression of DNA and histone modifiers contrarily to E. coli in a strain-specific manner.


Assuntos
Lactobacillus , Probióticos , Células CACO-2 , Epigênese Genética , Células Epiteliais , Escherichia coli/genética , Histonas , Humanos , Lactobacillus/genética , Probióticos/farmacologia , RNA Mensageiro
9.
Crit Rev Food Sci Nutr ; 62(3): 619-639, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33081489

RESUMO

The epigenome is an overall epigenetic state of an organism, which is as important as that of the genome for normal development and functioning of an individual. Epigenetics involves heritable but reversible changes in gene expression through alterations in DNA methylation, histone modifications and regulation of non-coding RNAs in cells, without any change in the DNA sequence. Epigenetic changes are owned by various environmental factors including pollution, microbiota and diet, which have profound effects on epigenetic modifiers. The bioactive compounds present in the diet mainly include curcumin, resveratrol, catechins, quercetin, genistein, sulforaphane, epigallocatechin-3-gallate, alkaloids, vitamins, and peptides. Bioactive compounds released during fermentation by the action of microbes also have a significant effect on the host epigenome. Besides, recent studies have explored the new insights in vitamin's functions through epigenetic regulation. These bioactive compounds exert synergistic, preventive and therapeutic effects when combined as well as when used with chemotherapeutic agents. Therefore, these compounds have potential of therapeutic agents that could be used as "Epidrug" to treat many inflammatory diseases and various cancers where chemotherapy results have many side effects. In this review, the effect of diet derived bioactive compounds through epigenetic modulations on in vitro and in vivo models is discussed.


Assuntos
Metilação de DNA , Epigênese Genética , Dieta , Genisteína/farmacologia , Resveratrol
10.
Nanotechnology ; 32(19): 195402, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33513599

RESUMO

Fabrication of noble-metal-free, efficient and stable hybrid photocatalyst is essential to address the rapidly growing energy crisis and environmental pollution. Here, MoS2 has been used as the co-catalyst on Bi-doped TiO2 to form a novel heterostructure to increase the utilization of the photogenerated charge carriers for improving photocatalytic H2 evolution activity through water reduction. Significantly increased photocatalytic H2 generation has been achieved on the optimized MoS2/Bi-TiO2 nanocomposite (∼512 µmol g-1) after 4 h of visible light illumination, which is nine times higher than that of the pristine TiO2 (∼57 µmol g-1). The measurements of photocurrent, charge transfer resistance and photo-stability of MoS2/Bi-TiO2 photoanode imply that charge separation efficiency has been improved in comparison to the pure MoS2 and TiO2 photoanodes. Further, the Mott-Schottky study confirmed that a p-n heterojunction has been formed between n-type MoS2 and p-type Bi-doped TiO2, which provides a potential gradient to increase charge separation and transfer efficiency. On the basis of these experimental results, this enhanced photocatalytic activity of MoS2/Bi-TiO2 heterostructures could be ascribed to the significant visible light absorption and the efficient charge carrier separation. Thus, this work demonstrates the effect of p-n junction for achieving high H2 evolution activity and photoelectrochemical water oxidation under visible light illumination.

11.
Trends Food Sci Technol ; 113: 423-429, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36570612

RESUMO

Background: COVID-19 has affected millions of people worldwide. Recently, international agencies have revealed that poverty and hunger could kill more people than COVID-19 victims. Many global workforces have lost their jobs during this pandemic situation. In developing countries, most of the workers and their families live hand to mouth, depending on daily wage, and loss of income would be a hunger pandemic. Globally, the proportion of undernourished and hungry people have been on an upswing due to climate changes and violent conflicts. The millions of people are facing chronic malnourishment and COVID-19 menaces undermining the endeavour of philanthropic and food security. COVID-19 has increased the risk of livelihood by the shortage of food and distraction of the supply chain especially in the developing countries where rural expanses depend on agriculture production and seasonal jobs. So, if they are forced to limit their activities, their livelihoods will be demolished. Scope and approach: COVID-19 is increasing the jeopardy of food prices over the world, which would prompt a crisis in several developing countries. The government organizations in developing countries are doing well to protect people from the current pandemic. But they are also in critical situation regarding food supply chains and are facing difficulties in providing nutrient-rich foods. The susceptible people are fraught to secure household income and manage their food. In this review, we have explored the food security approach, food supply chain and risk of food shortage. Every country in the world needs to implement effective interventions to maintain open trade and food supply chains, ensure access to nutrients for all at affordable prices and develop co-operation to preserve the flexibility of universal food markets.

12.
Microb Pathog ; 142: 104105, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32114155

RESUMO

Antibiotic mediated therapies target the growth-related processes of the pathogen hence imparting a strong selection pressure on the pathogen to develop antibiotic resistance. Recently anti-virulence strategies have gained lots of attention amongst the scientific community, wherein instead of inhibiting the normal growth of pathogens, it interferes with the regulation of virulence factors of the pathogens and impede their pathogenesis. In Pseudomonas aeruginosa, the virulence mechanism accountable for various types of infections in humans depends on N-acyl homoserine lactone (AHL) mediated quorum sensing. So quenching of these molecules, pose as a promising tool against P. aeruginosa pathogenesis. Lactic acid bacteria cell-free supernatant (acidic and neutralized) were evaluated in quorum quenching of P. aeruginosa PAO1 (MTCC 3541) after their initial screening for anti-biofilm potential against this pathogen.Though the reduction in biofilm formation with acidic and neutralized supernatants of lactic acid bacteria revealed strain specific response but acidic fractions showed much stronger (P ≤ 0.05) inhibition of biofilm irrespective of the type of challenge given to P. aeruginosa with lactic acid bacteria. The acidic fraction of supernatants (L. lactis, L. rhamnosus and L. fermentum) not only showed a significant reduction (P ≤ 0.05) in auto-inducer AHL levels but also diminished elastase activity which was among important virulence characters directly controlled by the quorum sensing signaling. Moreover, significant decrease (P ≤ 0.05) in mRNA expression of lasI and rhlI in presence of acidic fractions of lactic acid bacterial supernatants further confirmed the quorum quenching process in P. aeruginosa.

13.
Nanomedicine ; 17: 94-105, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30664947

RESUMO

MicroRNAs (miRNAs) are noncoding small RNA molecules that act as decisive roles in cell proliferation and differentiation processes by targeted inhibition of mature mRNA. In this study, miRNAs that are involved in the differentiation of neural stem cells (NSC) from human mesenchymal stem cells (MSC) were completely profiled and identified to elucidate the significant miRNAs responsible for NSC differentiation. Human MSCs were induced with NSC-differentiation cocktail containing epidermal growth factor and fibroblast growth factor under serum-free conditions. The profiling of miRNAs was done using Next-Generation sequencing system. The significant miRNAs that might be involved in the differentiation process were screened. The expression levels of target genes (ARID1A and DUSP16) of miR-561-5p and miR-138-5p were determined using western blot & quantitative PCR respectively. The results could help in developing new strategies towards optimizing the in vitro differentiation of NSCs for potential use in future clinical applications.


Assuntos
Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , Células-Tronco Neurais/citologia , Neurogênese , Linhagem Celular , Proteínas de Ligação a DNA , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neurais/metabolismo , Proteínas Nucleares/genética , Fatores de Transcrição/genética
14.
Biol Blood Marrow Transplant ; 23(9): 1592-1596, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28603069

RESUMO

Three-loci low-resolution (LR) or intermediate-resolution HLA typing is generally considered adequate in the related blood and marrow transplantation (BMT) context. However, a single high-resolution (HR) mismatch may have a similar adverse impact on BMT outcome as an LR one. We sought to determine the frequency of mismatches that may go undetected when standard typing (LR or 3-loci HR) is used compared with 6-loci HR typing for related donor compatibility testing, and to assess its impact on relevant BMT outcomes. We analyzed data from a total of 2554 6-loci (HLA-A, -B, -C, -DRB1, -DQB1, and -DPB1) HR sequence-based typing (full typing [FT]) from 754 patients, 1011 siblings, and 789 parents done at DKMS Germany (www.DKMS.de) between January 1, 2014, and June 21, 2016. We also studied 38 cases in which the family had undergone 3-loci HLA typing (standard typing [ST]). Patients were from India (70%), Pakistan (22%), and Sri Lanka (8%). The IMGT/HLA database (www.ebi.ac.uk/ipd/imgt/hla) was used to tease out nonpermissive DPB1 mismatches. HLA disparity-related outcomes, such as rejection and graft-versus-host disease (GVHD) were assessed in a retrospective matched-pair cohort of 50 patients (25 with ST and 25 with FT) who underwent BMT for severe thalassemia from compatible related donors. We found fully matched (either 12/12 HR matches or with a single permissive DPB1 mismatch) related donors for 285 patients (38%). Of these donors, 89% were siblings and 11% were parents. The likelihood of matching on an individual locus on LR but not on HR was found to be 5%. A total of 9 donors (3%; 7 siblings and 2 parents) who would have been considered a full match by HR typing on A, B, and DRB1 alone were not a match by extended 6-loci HR typing. Five of these 9 donors had a mismatch on C or DQB1, and 4 had a nonpermissive DPB1 mismatch. In this group, 5 donors (56%) belonged to a consanguineous family, in 2 donors (22%) there was no reported consanguinity, and in 2 donors (22%) consanguinity was unknown. We identified 18 donors (6%; 13 siblings and 5 parents) who would have been considered a 12/12 match by LR HLA typing alone but were found not to match on extended HR typing. In this group, 11 donors (61%) were from consanguineous families, 3 donors (17%) had no reported consanguinity, and in 4 donors (22%) consanguinity was unknown. Outcome analysis showed that the actuarial proportion of patients with GVHD was 4% in the FT group compared with 16% in the ST group, with log-rank P = .1952. The ST group included 2 patients with grade III-IV acute GVHD and 1 patient each with moderate and severe chronic GVHD, whereas the FT group only 1 patient with grade III acute GVHD. We conclude that even in the context of related donors, the use of LR and/or 3-loci (A, B, and DRB1) HR HLA typing might result in a sizable risk of missing a clinically relevant mismatch, which may have an adverse impact on transplantation outcomes. In the Indian subcontinent, this observation is not limited to putatively compatible parents or consanguineous families; we recommend full 6-loci HR HLA typing even for matched related BMTs.


Assuntos
Transplante de Medula Óssea , Rejeição de Enxerto/prevenção & controle , Doença Enxerto-Hospedeiro/prevenção & controle , Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas , Teste de Histocompatibilidade/métodos , Talassemia/terapia , Criança , Pré-Escolar , Consanguinidade , Bases de Dados de Proteínas , Família , Feminino , Expressão Gênica , Loci Gênicos , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Antígenos HLA/classificação , Antígenos HLA/genética , Humanos , Índia , Lactente , Masculino , Paquistão , Estudos Retrospectivos , Sri Lanka , Talassemia/imunologia , Talassemia/patologia , Doadores não Relacionados
15.
Mol Biol Rep ; 43(12): 1383-1394, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27614750

RESUMO

p53 helps in maintaining genomic stability by undergoing cellular arrest, DNA repair or cellular apoptosis during DNA damage. So, as to find the association of p53Arg 72 Pro towards lung carcinogenesis and overall survival of North Indian lung cancer patients, single nucleotide polymorphic variant (rs1042522) was analyzed. 840 subjects including 420 cases and 420 controls were recruited and genotyped using PCR-RFLP technique for p53Arg 72 Pro polymorphic site. Association was analyzed using adjusted odds ratio along with its confidence intervals (95 % CI) and p value predicted from logistic regression whereas overall survival for lung cancer patients was obtained using Kaplan-Meir and Cox regression model for different parameters to obtain hazard ratio and survival time with statistical significance (log-rank p value). None of the variant genotypes for p53Arg 72 Pro showed any association towards lung cancer risk or any specific histological subtype. Lung cancer subjects with Pro/Pro genotype had better median survival time as compared to Arg/Pro genotype (10 months; HR = 0.65; 95 % CI = 0.45-0.95; p = 0.03). Furthermore, female lung cancer patients with Arg/Pro (HR = 0.08; 95 % CI = 0.02-0.34; p = 0.0005) and Pro/Pro (HR = 0.21; 95 % CI = 0.06-0.67; p = 0.008) genotypes showed a better overall survival and hence a better prognosis as compared to males. Our data also reveals that lung cancer patients with ECOG scores between 0 and 1 and carrying the Pro/Pro had better chances of survival. p53 codon 72 polymorphism could play a role as a prognostic marker in lung cancer patients.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/genética , Neoplasias Pulmonares/genética , Compostos de Platina/uso terapêutico , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/mortalidade , Estudos de Casos e Controles , Códon , Resistencia a Medicamentos Antineoplásicos , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Índia , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Compostos de Platina/farmacologia , Polimorfismo de Nucleotídeo Único , Prognóstico , Modelos de Riscos Proporcionais , Resultado do Tratamento , Adulto Jovem
16.
Int J Biol Macromol ; 264(Pt 2): 130814, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479664

RESUMO

Recently, various advancements have been made in the development of functional polymeric materials for innovative applications. Herein this work, functionalization of sterculia gum (SG) was carried out via grafting of poly(2-(methacryloyloxy) ethyltrimethylammonium chloride) (METAC)-polyvinyl pyrrolidone (PVP) to develop hydrogel dressings as a platform for use in drug delivery (DD). The innovation of the present work is the exploration of inherent antioxidant and antimicrobial properties of the SG along with antimicrobial characteristic of poly(METAC) and PVP, to design the doxycycline encapsulated hydrogel dressings for better wound healing. FESEM, EDS and AFM analyzed the surface morphology of hydrogels. FTIR, 13C NMR and XRD inferred inclusion of poly(METAC)-PVP into polymers. 13C NMR confirmed the incorporation of poly(METAC) and PVP onto gum by the presence of a peak at 54.74 ppm because of methyl carbon attached to quaternary nitrogen of poly(METAC) and at 45.48 ppm due to the ring carbon of PVP along with FTIR peak at 949 cm-1 because of CN bending of quaternary nitrogen of poy (METAC). Thermal characterization of copolymers has been performed using TGA analysis. One gram of copolymeric hydrogel dressing absorbed 6.51 ± 0.03 g simulated salivary fluid (SSF) and 7.65 ± 0.03 g simulated wound fluid (SWF). Release of doxycycline drug occurred in a sustained manner and followed the Non-Fickian diffusion mechanism from hydrogels. The release profile was most effectively described by Hixon-Crowell kinetic model. Hydrogel demonstrated biocompatibility and expressed thrombogenicity 79.7 ± 4.9 % during its polymer-blood interactions. Copolymer revealed mucoadhesive property, requiring a force of 77.00 ± 0.01 mN to detach from bio-membrane. Additionally, it exhibited antioxidant features, showing 43.81 ± 0.286 % free radical scavenging. Hydrogel dressings were mechanically stable and revealed 0.76 ± 0.09 N mm-2 tensile strength and 9.18 ± 0.01 N burst strength. Polymer films were permeable to oxygen and water vapor and were impermeable to microorganisms. Hydrogel dressings exhibited antimicrobial properties against Pseudomonas aeruginosa and Staphylococcus aureus bacteria. Overall, these properties displayed the suitability of hydrogels for wound dressing (WD) applications which may actively enhance wound healing.


Assuntos
Anti-Infecciosos , Sterculia , Hidrogéis/química , Sterculia/química , Doxiciclina , Antioxidantes/farmacologia , Antioxidantes/química , Goma de Karaya/química , Polímeros/química , Povidona , Carbono , Nitrogênio , Antibacterianos/farmacologia , Antibacterianos/química
17.
Chemosphere ; 363: 142812, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004150

RESUMO

Patients with impaired immune systems are particularly vulnerable to infections. With the increasing number of immunocompromised patients, it becomes necessary to design studies that evaluate the effects of toxic contaminants that are a part of our daily lives. Simultaneously, the management of these toxic components also becomes essential. Therefore, the present study evaluated the possible protective role of cinnamaldehyde (Cin) against tenuazonic acid-induced mycotoxicosis in the immunosuppressed murine model. Tenuazonic acid (TeA), a toxin usually produced by Alternaria species, is a common contaminant in tomato and tomato-based products. Evaluating the potential toxicity of a hazardous chemical necessitates the use of in vitro, in vivo, and in silico methods. Here, the immunomodulatory effect of TeA was assessed in vitro using mouse splenocytes. In silico docking was carried out for the tumour markers of eight organs and TeA. The haematological, histopathological, and biochemical aspects were analysed in vivo. The sub-chronic intoxication of mice with TeA showed elevated malondialdehyde, reduced catalase, and superoxide dismutase production, along with abnormal levels of aspartate aminotransferase and alanine transaminase. The treatment with Cin prevented TeA-induced alterations of antioxidant defense enzyme activities and significantly forbade TeA-induced organ damage, showing therapeutic effects and toxicity reduction in TeA-induced mycotoxicosis.

18.
Int J Biol Macromol ; : 134396, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39097063

RESUMO

The main focus of the present research is to design network hydrogels derived from natural polymers to promote a sustainable future. Multifunctional hydrogels were prepared by combining sterculia gum (SG), phosphorester -cyclic amide polymers for bio-medical applications including drug delivery (DD). The antibiotic drug ceftriaxone was incorporated into hydrogels to enhance wound healing potential. The surface morphology of copolymers was investigated by using FESEM and AFM techniques. FTIR and 13C NMR spectroscopic techniques provided insight into the formation of network structures. In FTIR analysis, distinctive bands were identified: at 1649 cm-1 attributed to CO stretching of the cyclic amide of PVP, at 1147 cm-1 and 974 cm-1 representing PO stretching and P-O-C of poly(BMEP), respectively. In the 13C NMR spectrum, a prominent peak at 63.272 ppm revealed the presence of (O-CH2) linkage of poly(BMEP). XRD demonstrated amorphous characteristics of hydrogels. The interactions of copolymer with blood, bio-membrane and encapsulated drug illustrated their biocompatibility, bio-adhesion and controlled DD properties. The dressings expressed a hemolytic index value of 2.58 ±â€¯0.03 %. The hydrogels exhibited mucoadhesive character, revealed from the adhesion force of 50.0 ±â€¯5 mN needed to separate polymer dressing from the mucosa. Dressings exhibited antioxidant properties and displayed 33.73 ±â€¯0.3 % radical scavenging in the DPPH assay. Protein adsorption test of copolymer illustrated 9.48 ±â€¯0.970 % of albumin adsorption. The tensile strength of the dressing was found 0.54 ±â€¯0.03 N mm-2 while the burst strength 9.92 ±â€¯0.27 N was observed. The sustained release of the drug was provided by supra-molecular interactions. Drug release followed a non-Fickian diffusion mechanism and the release profile was best described by the Higuchi kinetic model. Additionally, hydrogel dressings revealed permeability to H2O vapors and O2 and antimicrobial activity. These findings suggest the suitability of sterculia gum-based hydrogels for DD uses.

19.
Int J Gynaecol Obstet ; 164(2): 708-713, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37551118

RESUMO

OBJECTIVE: To determine the effect of preoperative vaginal cleansing with chlorhexidine and cetrimide solution on postoperative infectious morbidity. METHODS: This prospective cohort study was conducted over a period of 18 months in the Department of Obstetrics and Gynecology, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, India. Women undergoing cesarean section were alternately allotted to study and control groups. Women with chorioamnionitis, antepartum hemorrhage, rupture of membranes for more than 24 h, and fever in the preoperative period were excluded. The study group received preoperative vaginal cleansing with antiseptic solution (7.5% chlorhexidine w/v and 15% cetrimide w/v); the control group did not receive vaginal cleansing. Both groups were followed for the presence of any infectious morbidity until they were discharged from the hospital. RESULTS: Age, body mass index (calculated as weight in kilograms divided by the square of height in meters), gestational age, and the parity of the women in the study and control groups were comparable (n = 760). The rate of endometritis was lower in the study group, but the difference was not statistically significant (P = 0.054). Post-cesarean febrile morbidity and wound sepsis were significantly lower in the study group (P = 0.017 and P = 0.02, respectively). On subgroup analysis, women in the study group with rupture of the membranes before cesarean delivery had lower wound sepsis and a reduced duration of hospital stay. Women in the study group with emergency cesarean delivery showed a significant reduction in wound sepsis, febrile morbidity, and length of hospital stay. CONCLUSION: Preoperative vaginal cleansing with chlorhexidine and cetrimide solution before a cesarean section reduces postoperative infectious morbidity.


Assuntos
Anti-Infecciosos Locais , Endometrite , Sepse , Feminino , Gravidez , Humanos , Clorexidina , Anti-Infecciosos Locais/uso terapêutico , Povidona-Iodo , Cetrimônio , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Cesárea , Centros de Atenção Terciária , Estudos Prospectivos , Administração Intravaginal , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Febre/epidemiologia , Febre/prevenção & controle
20.
Mater Horiz ; 11(1): 184-195, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37937438

RESUMO

Gas sensors based on tin dioxide (SnO2) for the detection of ammonia (NH3) have become commercially available for environmental monitoring due to their reactive qualities when exposed to different gaseous pollutants. Nevertheless, their implementation in the medical field has been hindered by certain inherent drawbacks, such as needing to operate at high temperatures, lack of selectivity, unreliable operation under high-humidity conditions, and a lower detection limit. To counter these issues, this study created 2D nanosheets of SnO2 through an optimized solvothermal method. It was found that tuning the precursor solution's pH to either neutral or 14 led to aggregated or distributed, uniform-size nanosheets with a higher crystallinity, respectively. Remarkably, the SnO2 nanosheet sensor (SNS-14) displayed a much lower response to water molecules and specific reactivity to ammonia even when subjected to reducing and oxidizing agents at 25 °C due to the micropores and chemisorbed oxygen on the nanosheets. Furthermore, the SNS-14 was seen to have the highest sensitivity to ammonia at 100 ppm, with rapid response (8 s) and recovery times (55 s) even at a high relative humidity of 70%. Its theoretical detection limit was recorded to be 64 ppt, better than any of the earlier SnO2-based chemiresistive sensors. Its exceptional sensing abilities were credited to its optimal crystallinity, specific surface area, defects, chemisorbed oxygen, and porous structure. NH3-TPD measurements and computational simulations were employed to understand the ammonia interaction with atomistic details on the SnO2 nanosheet surface. A real time breath sensing experiment was simulated to test the efficacy of the sensor. Reaching this advancement is an achievement in bypassing past boundaries of SnO2-centered sensors, making it feasible to detect ammonia with enhanced precision, discrimination, dependability, and velocity for probable usages in medical diagnostics and ecological surveillance.

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