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1.
Pharmacogenet Genomics ; 33(3): 51-58, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36853844

RESUMO

OBJECTIVES: Type 2 diabetes (T2D) imposes an enormous burden all over the world in both developed and developing countries. Inter-individual differences are attributed to polymorphisms in candidate genes resulting in altered absorption, transportation, distribution, and metabolism of oral antidiabetic drugs (OADs). Hence, the present study was undertaken to evaluate the pharmacogenetic impact of SLC22A1 gene variant rs628031 (G/A) on metformin monotherapy in newly diagnosed untreated T2D patients. METHODS: Newly diagnosed T2D patients ( n = 500) were enrolled according to inclusion/exclusion criteria. Initially, enrolled subjects were prescribed metformin monotherapy and followed up for at least 12 weeks. Response to metformin was evaluated in 478 patients who revisited for follow-up by measuring HbA1c. RESULT: Out of 478 patients, 373 were responders to metformin monotherapy while 105 were non-responders. The pharmacogenetic impact was evaluated by genotype, haplotype, and pharmacogenetic analyses. 'GG' genotype and 'G' allele of SLC22A1 rs628031 G/A were observed in 48.8% and 67.7% of Met responders, respectively, while 20.9% and 49.1 % were in non-responders. Therefore, there was a 2.18-fold increase in the success rate of Met therapeutics. CONCLUSION: Individuals carrying the 'GG' genotype or 'G' allele for SLC22A1 gene variant rs628031 G/A are better responders for Metformin monotherapy.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Transportador 1 de Cátions Orgânicos , Humanos , Alelos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Genótipo , Metformina/uso terapêutico , Farmacogenética , Transportador 1 de Cátions Orgânicos/genética
2.
Int J Neurosci ; : 1-11, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35896309

RESUMO

Glioblastoma is an aggressive type of cancer that begins in cells called astrocytes that support nerve cells that can occur in the brain or spinal cord. It can form in the brain or spinal cord. Despite the variety of modern therapies against GBM, it is still a deadly disease. Patients usually have a median survival of approximately 14 to 15 months from the diagnosis. Glioblastoma is also known as glioblastoma multiforme. The pathogenesis contributing to the proliferation and metastasis of cancer involves aberrations of multiple signalling pathways through multiple genetic mutations and altered gene expression. The coagulant factors like thrombin and tissue factor play a noteworthy role in cancer invasion. They are produced in the microenvironment of glioma through activation of protease-activated receptors (PARs) which are activated by coagulation proteases. PARs are members of family G-protein-coupled receptors (GPCRs) that are activated by coagulation proteases. These components play a key role in tumour cell angiogenesis, migration, invasion, and interactions with host vascular cells. Further, the release of neurotransmitters is also found to regulate malignancy in gliomas. Exploration of the interplay between malignant neural circuitry with the normal conditions is also decisive in finding effective therapies for these apparently invasive tumours. The present review discusses the molecular classification of gliomas, activation of PARs by coagulation protease, and its role in metastasis of gliomas. Further, the differential involvement of neurotransmitters in the pathogenesis of gliomas has also been discussed. Targeting these molecules may present a potential therapeutic approach for the treatment of gliomas.

3.
Circ Res ; 123(2): 266-287, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29976692

RESUMO

Given the rising prevalence of cardiovascular disease worldwide and the limited therapeutic options for severe heart failure, novel technologies that harness the regenerative capacity of the heart are sorely needed. The therapeutic use of stem cells has the potential to reverse myocardial injury and improve cardiac function, in contrast to most current medical therapies that only mitigate heart failure symptoms. Nearly 2 decades and >200 trials for cardiovascular disease have revealed that most cell types are safe; however, their efficacy remains controversial, limiting the transition of this therapy from investigation to practice. Lessons learned from these initial studies are driving the design of new clinical trials; higher fidelity of cell isolation techniques, standardization of conditions, more consistent use of state of the art measurement techniques, and assessment of multiple end points to garner insights into the efficacy of stem cells. Translation to clinical trials has almost outpaced our mechanistic understanding, and individual patient factors likely play a large role in stem cell efficacy. Therefore, careful analysis of dosing, delivery methods, and the ideal patient populations is necessary to translate cell therapy from research to practice. We are at a pivotal stage in the field in which information from many relatively small clinical trials must guide carefully executed efficacy trials. Larger efficacy trials are being launched to answer questions about older, first-generation stem cell therapeutics, while novel, second-generation products are being introduced into the clinical realm. This review critically examines the current state of clinical research on cell-based therapies for cardiovascular disease, highlighting the controversies in the field, improvements in clinical trial design, and the application of exciting new cell products.


Assuntos
Doenças Cardiovasculares/terapia , Ensaios Clínicos como Assunto , Medicina Regenerativa/métodos , Transplante de Células-Tronco/métodos , Humanos , Medicina Regenerativa/tendências , Transplante de Células-Tronco/efeitos adversos , Transplante de Células-Tronco/tendências
4.
Ecotoxicol Environ Saf ; 201: 110811, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32544744

RESUMO

Xenobiotic mediated renal toxicity is one of the major health concerns to the organisms, including humans. New chemicals with nephrotoxic potential are continuously being added to the list of existing nephrotoxicants. To predict the nephrotoxicity of these new chemicals, reliable and cost-effective alternative animal models are required. It is a prerequisite for the identification and assessment of these compounds as potential nephrotoxicants to prevent renal toxicity in the exposed population. Drosophila melanogaster, a genetically tractable invertebrate animal model, has a renal system functionally analogous to humans. The Malpighian tubules (MTs) of D. melanogaster are similar to the tubular part of nephron of the human kidney. Besides, it recapitulates the renal toxicity hallmark with mammals when exposed to known nephrotoxicants. In this study, first instar larvae of D. melanogaster (Oregon R) were exposed to different concentrations of two well-known nephrotoxicants, cadmium (Cd) and mercury (Hg). Akin to higher organisms, Cd and Hg exposure to D. melanogaster produce similar phenotypes. MTs of exposed D. melanogaster larvae exhibited increased oxidative stress, activated cellular antioxidant defense mechanism, GSH depletion, increased cleaved caspase-3 expression, increased DEVDase activity and increased cell death. The functional status of MTs was assessed by fluid secretion rate (FSR), efflux activity of transporter protein, mitochondrial membrane potential (MMP), ATP level and expression of junctional protein (Dlg). All the phenotypes observed in MTs of D. melanogaster larvae recapitulate the phenotypes observed in higher organisms. Increased uric acid level, the hallmark of renal dysfunction, was also observed in exposed larvae. Taken together, the study suggests that MTs of D. melanogaster may be used as a functional model to evaluate xenobiotic mediated nephrotoxicity.


Assuntos
Alternativas aos Testes com Animais , Cádmio/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Rim/efeitos dos fármacos , Túbulos de Malpighi/efeitos dos fármacos , Mercúrio/toxicidade , Animais , Antioxidantes/metabolismo , Transporte Biológico , Cádmio/metabolismo , Humanos , Rim/metabolismo , Larva/efeitos dos fármacos , Túbulos de Malpighi/metabolismo , Mercúrio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Xenobióticos/metabolismo , Xenobióticos/toxicidade
5.
J Card Surg ; 35(2): 492-494, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31794108

RESUMO

BACKGROUND: Left ventricular assist device (LVAD) implantation is a lifesaving intervention in advanced heart failure. However, LVAD is not without complication. In this case, an inadvertent intraperitoneal driveline caused small bowel obstruction, subsequently requiring pexy of the driveline to the abdominal wall to avoid future complications. CASE PRESENTATION: A 37-year-old male with worsening, nonischemic, dilated cardiomyopathy underwent LVAD implantation. Postoperative day (POD) 15 he developed small bowel obstruction, and abdominal exploration showed transition point at an inadvertently placed intraperitoneal LVAD driveline. The patient was LVAD-dependent precluding removal, so the driveline was secured to the anterior abdominal wall. He subsequently improved and was discharged. CONCLUSIONS: While LVAD is increasingly common for heart failure patients, the tunneled driveline may inadvertently enter the peritoneal cavity where it can cause significant morbidity. In this case, we propose securing the driveline to the abdominal wall to prevent complications when LVAD removal is not an option.


Assuntos
Remoção de Dispositivo/métodos , Ventrículos do Coração , Coração Auxiliar/efeitos adversos , Obstrução Intestinal/etiologia , Intestino Delgado , Complicações Pós-Operatórias/etiologia , Implantação de Prótese/efeitos adversos , Adulto , Cardiomiopatias/cirurgia , Humanos , Masculino , Cavidade Peritoneal , Implantação de Prótese/métodos
6.
Microb Pathog ; 136: 103704, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31479726

RESUMO

Visceral leishmaniasis (VL) is a dreadful protozoan disease caused by Leishmania donovani that severely affects huge populations in tropical and sub-tropical regions. The present study reports an unbiased genome based screening of 4 potent vaccine antigens against 8023 L. donovani proteins by following the criteria of presence of signal peptides, GPI-anchors and ≤1 transmembrane helix using advanced bioinformatics tools viz. SignalP4.0, PredGPI and TMHMM2.0, respectively. They are designated as genome based predicted signal peptide antigens (GBPSPA). The antigenicity/immunogenicity of chosen vaccine antigens (GBPSPA) with 4 randomly selected known leishmanial antigens (RSKLA) was compared by simulation study employing C-ImmSim software for human immune responses. This revealed better immunological responses. These antigens were further evaluated for the presence of B- and T-cell epitopes using immune epitope database (IEDB) based recommended consensus method of MHC class I and II tools. It was found to forecast CD4+ and CD8+ T-cell responses in genetically diverse human population worldwide as well as different endemic regions through IEDB based predicted population coverage (PPC) analysis tool. The worldwide percent PPC value of combined (HLA class I and II) epitope ensemble forecast was found to be 99.98, 99.96 and 50.04, respectively for GBPSPA, RSKLA and experimentally known epitopes (EKE) of L. donovani. Therefore, these potential antigens/epitope ensembles could favor the design of prospective and novel vaccine constructs like self-assembled epitopes as nano vaccine formulations against VL. Overall, the present study will serve as a model framework that might improve the effectiveness of designed vaccine against L. donovani and other related pathogens.


Assuntos
Antígenos de Protozoários/imunologia , Epitopos/imunologia , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/prevenção & controle , Vacinas Protozoárias/isolamento & purificação , Antígenos de Protozoários/genética , Biologia Computacional , Epitopos/genética , Testes Genéticos , Humanos , Leishmania donovani/genética , Vacinas Protozoárias/genética , Vacinas Protozoárias/imunologia , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/isolamento & purificação
7.
Circ Res ; 121(11): 1279-1290, 2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-28923793

RESUMO

RATIONALE: Cell dose and concentration play crucial roles in phenotypic responses to cell-based therapy for heart failure. OBJECTIVE: To compare the safety and efficacy of 2 doses of allogeneic bone marrow-derived human mesenchymal stem cells identically delivered in patients with ischemic cardiomyopathy. METHODS AND RESULTS: Thirty patients with ischemic cardiomyopathy received in a blinded manner either 20 million (n=15) or 100 million (n=15) allogeneic human mesenchymal stem cells via transendocardial injection (0.5 cc per injection × 10 injections per patient). Patients were followed for 12 months for safety and efficacy end points. There were no treatment-emergent serious adverse events at 30 days or treatment-related serious adverse events at 12 months. The Major Adverse Cardiac Event rate was 20.0% (95% confidence interval [CI], 6.9% to 50.0%) in 20 million and 13.3% (95% CI, 3.5% to 43.6%) in 100 million (P=0.58). Worsening heart failure rehospitalization was 20.0% (95% CI, 6.9% to 50.0%) in 20 million and 7.1% (95% CI, 1.0% to 40.9%) in 100 million (P=0.27). Whereas scar size reduced to a similar degree in both groups: 20 million by -6.4 g (interquartile range, -13.5 to -3.4 g; P=0.001) and 100 million by -6.1 g (interquartile range, -8.1 to -4.6 g; P=0.0002), the ejection fraction improved only with 100 million by 3.7 U (interquartile range, 1.1 to 6.1; P=0.04). New York Heart Association class improved at 12 months in 35.7% (95% CI, 12.7% to 64.9%) in 20 million and 42.9% (95% CI, 17.7% to 71.1%) in 100 million. Importantly, proBNP (pro-brain natriuretic peptide) increased at 12 months in 20 million by 0.32 log pg/mL (95% CI, 0.02 to 0.62; P=0.039), but not in 100 million (-0.07 log pg/mL; 95% CI, -0.36 to 0.23; P=0.65; between group P=0.07). CONCLUSIONS: Although both cell doses reduced scar size, only the 100 million dose increased ejection fraction. This study highlights the crucial role of cell dose in the responses to cell therapy. Determining optimal dose and delivery is essential to advance the field, decipher mechanism(s) of action and enhance planning of pivotal Phase III trials. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02013674.


Assuntos
Cardiomiopatias/cirurgia , Transplante de Células-Tronco Mesenquimais/métodos , Infarto do Miocárdio/complicações , Disfunção Ventricular Esquerda/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Feminino , Florida , Nível de Saúde , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/metabolismo , Miocárdio/patologia , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Qualidade de Vida , Recuperação de Função Fisiológica , Volume Sistólico , Fatores de Tempo , Transplante Homólogo , Resultado do Tratamento , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda , Adulto Jovem
8.
Indian J Med Res ; 140(1): 60-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25222779

RESUMO

BACKGROUND & OBJECTIVES: Diabetes is a metabolic pro-inflammatory disorder characterized by chronic hyperglycaemia and increased levels of circulating cytokines suggesting a causal role for inflammation in its aetiology. In order to decipher the role of interleukin-6 (IL-6) in type 2 diabetes mellitus (T2DM) we analyzed two promoter polymorphisms -597 A/G (rs1800797) and -174 G/C (rs1800795) in T2DM cases from north India, and in healthy controls. METHODS: DNA was isolated from venous blood samples of T2DM patients (n=213) and normal healthy controls (n=145). Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed after biochemical analysis. The genotypic and allelic frequency distributions were analyzed. RESULTS: The clinical/biochemical parameters of T2DM cases when compared to controls showed a significant difference. No significant association was observed with -597A/G polymorphism while, -174 G/C showed a highly significant association (P<0.001). In haplotypic analysis, combination of -597GFNx01/-174CFNx01 showed significant association (P=0.010). INTERPRETATION & CONCLUSIONS: Our data suggest that IL-6 gene polymorphisms play a prominent role in T2DM disease susceptibility in population from north India.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença/genética , Interleucina-6/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Adulto , Idoso , Sequência de Bases , Feminino , Componentes do Gene , Frequência do Gene , Genótipo , Haplótipos/genética , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
9.
Indian J Hum Genet ; 20(1): 10-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24959009

RESUMO

Type 2 diabetes mellitus (T2DM), by definition is a heterogeneous, multifactorial, polygenic syndrome which results from insulin receptor (IR) dysfunction. It is an outcome of oxidative stress caused by interactions of reactive metabolites (RMs) with lipids, proteins and other molecules of the human body. Production of RMs mainly superoxides (•O2 (-)) has been found in a variety of predominating cellular enzyme systems including nicotinamide adenine dinucleotide phosphate oxidase, xanthine oxidase, cyclooxygenase, endothelial nitric oxide synthase (eNOS) and myeloperoxidase. The four main RM related molecular mechanisms are: increased polyol pathway flux; increased advanced glycation end-product formation; activation of protein kinase C isoforms and increased hexosamine pathway flux which have been implicated in glucose-mediated vascular damage. Superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and NOS are antioxidant enzymes involved in scavenging RMs in normal individuals. Functional polymorphisms of these antioxidant enzymes have been reported to be involved in the pathogenesis of T2DM. The low levels of antioxidant enzymes or their non-functionality results in excessive RMs which initiates stress related pathways thereby leading to IR and T2DM. An attempt has been made to review the role of RMs and antioxidant enzymes in oxidative stress resulting in T2DM.

10.
Gene ; 928: 148746, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004322

RESUMO

Gestational Diabetes Mellitus (GDM) is a medical complication during the gestational period in which woman who had never been diagnosed with diabetes develops hyperglycemia. Prior studies have demonstrated that the advancement of GDM and its consequences arises from a disparity between oxidants and antioxidants in the cells. The observed outcomes can be attributed to an excessive formation of reactive oxygen species (ROS) within the cells, coupled with a reduced activity of anti-oxidative enzymes. Glutathione S-transferase (GSTs) is recognized as an antioxidant enzyme that is belong to as a phase II family member of detoxifying enzymes. These metabolic multigene catalysts are found into the cytoplasm of the cell. GSTs play a vital part in the elimination of cellular ROS or free radicals. The study involves total 300 pregnant women, (150 GDM cases and 150 healthy controls). The polymorphism study of GSTs genes (GSTM1 and GSTT1) was determined by conventional Polymerase Chain Reaction (PCR). The mRNA expression study of GSTM1 and GSTT1 genes analysed by qPCR/ RT-PCR (quantitative PCR/Real-Time PCR) followed by statistical analysis done using Prism8 software (version 8.01). The study revealed statistically significant variations in biochemical parameters between GDM cases and controls. It was found GSTM1-null (GSTM1-/-) polymorphism significantly (P < 0.0001) most prevalent in GDM cases (56.7%) when compared to healthy control (28%). However, no significant difference was observed for GSTT1 null and present polymorphism (P = 0.906). The gene expression levels of both GSTM1 and GSTT1 were found considerably downregulated in individuals with GDM as compared to the control group (P < 0.0001). The downregulation of gene expression has a significant (P<0.0001) association with the null/deletion polymorphism of both GSTM1/ GSTT1 genes respectively. Null/deletion genotype of GSTM1 gene and its expression showed significant association with GDM. Therefore, this gene variant has the potential to be used as a prognostic biomarker for GDM. However, there is need to study this gene variant in larger sample size and different ethnicity.

11.
Crit Rev Oncol Hematol ; 194: 104240, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38122918

RESUMO

Cervical cancer (CaCx) is the deadliest malignancy among women which is caused by human papillomavirus (HPV) and anthro-demographical/clinicopathological factors. HPV oncoproteins E6 and E7 target p53 and RB (retinoblastoma) protein degradation, Ataxia telangiectasia mutated (ATM), ATM-RAD3-related (ATR) inactivation and subsequent impairment of non-homologous end joining (NHEJ), homologous recombination, and base excision repair pathways. There is also an accumulation of genetic and epigenetic alterations in Tumor Growth Suppressors (TGS), oncogenes, and DNA repair genes leading to increased genome instability and CaCx development. These alterations might be responsible for differential clinical response to Cisplatin-based chemoradiotherapy (CRT) in patients. This review explores HPV-mediated DNA damage as a risk factor in CaCx development, the mechanistic role of genetic and epigenetic alterations in DNA repair genes and their association with CRT and outcome, It also explores new possibilities for the development of genetic and epigenetic-based biomarkers for diagnostic, prognostic, and molecular therapeutic interventions.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/terapia , Neoplasias do Colo do Útero/patologia , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/patologia , DNA , Reparo do DNA/genética , Epigênese Genética , Resultado do Tratamento
12.
World J Diabetes ; 15(4): 606-622, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38680697

RESUMO

Coronavirus disease 2019 (COVID-19) is a disease that caused a global pandemic and is caused by infection of severe acute respiratory syndrome coronavirus 2 virus. It has affected over 768 million people worldwide, resulting in approximately 6900000 deaths. High-risk groups, identified by the Centers for Disease Control and Prevention, include individuals with conditions like type 2 diabetes mellitus (T2DM), obesity, chronic lung disease, serious heart conditions, and chronic kidney disease. Research indicates that those with T2DM face a heightened susceptibility to COVID-19 and increased mortality compared to non-diabetic individuals. Examining the renin-angiotensin system (RAS), a vital regulator of blood pressure and pulmonary stability, reveals the significance of the angiotensin-converting enzyme (ACE) and ACE2 enzymes. ACE converts angiotensin-I to the vasoconstrictor angiotensin-II, while ACE2 counters this by converting angiotensin-II to angiotensin 1-7, a vasodilator. Reduced ACE2 expression, common in diabetes, intensifies RAS activity, contributing to conditions like inflammation and fibrosis. Although ACE inhibitors and angiotensin receptor blockers can be therapeutically beneficial by increasing ACE2 levels, concerns arise regarding the potential elevation of ACE2 receptors on cell membranes, potentially facilitating COVID-19 entry. This review explored the role of the RAS/ACE2 mechanism in amplifying severe acute respiratory syndrome coronavirus 2 infection and associated complications in T2DM. Potential treatment strategies, including recombinant human ACE2 therapy, broad-spectrum antiviral drugs, and epigenetic signature detection, are discussed as promising avenues in the battle against this pandemic.

14.
Sci Rep ; 14(1): 2128, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38267527

RESUMO

The most common denture material used for dentistry is poly-methyl-methacrylate (PMMA). Usually, the polymeric PMMA material has numerous biological, mechanical and cost-effective shortcomings. Hence, to resolve such types of drawbacks, attempts have been made to investigate fillers of the PMMA like alumina (Al2O3), silica (SiO2), zirconia (ZrO2) etc. For the enhancement of the PMMA properties a suitable additive is required for its orthopedic applications. Herein, the main motive of this study was to synthesize a magnesium oxide (MgO) reinforced polymer-based hybrid nano-composites by using heat cure method with superior optical, biological and mechanical characteristics. For the structural and vibrational studies of the composites, XRD and FT-IR were carried out. Herein, the percentage of crystallinity for all the fabricated composites were also calculated and found to be 14.79-30.31. Various physical and optical parameters such as density, band gap, Urbach energy, cutoff energy, cutoff wavelength, steepness parameter, electron-phonon interaction, refractive index, and optical dielectric constant were also studied and their values are found to be in the range of 1.21-1.394 g/cm3, 5.44-5.48 eV, 0.167-0.027 eV, 5.68 eV, 218 nm, 0.156-0.962, 4.273-0.693, 1.937-1.932, and 3.752-3.731 respectively. To evaluate the mechanical properties like compressive strength, flexural strength, and fracture toughness of the composites a Universal Testing Machine (UTM) was used and their values were 60.3 and 101 MPa, 78 and 40.3 MPa, 5.85 and 9.8 MPa-m1/2 respectively. Tribological tests of the composites were also carried out. In order to check the toxicity, MTT assay was also carried out for the PM0 and PM15 [(x)MgO + (100 - x) (C5O2H8)n] (x = 0 and 15) composites. This study provides a comprehensive insight into the structural, physical, optical, and biological features of the fabricated PMMA-MgO composites, highlighting the potential of the PM15 composite with its enhanced density, mechanical strength, and excellent biocompatibility for denture applications.


Assuntos
Óxido de Magnésio , Polimetil Metacrilato , Dióxido de Silício , Espectroscopia de Infravermelho com Transformada de Fourier , Polímeros , Materiais Dentários
15.
ACS Biomater Sci Eng ; 10(4): 2116-2132, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38498674

RESUMO

Due to excellent biocompatibility, bioactivities, and osteoconductivity, hydroxyapatite (HAp) is considered as one of the most suitable biomaterials for numerous biomedical applications. Herein, HAp was fabricated using a bottom-up approach, i.e., a wet chemical method, and its composites with TiC, h-BN, and ZrO2 were fabricated by a solid-state reaction method with enhanced mechanical and biological performances. Structural, surface morphology, and mechanical behavior of the fabricated composites were characterized using various characterization techniques. Furthermore, transmission electron microscopy study revealed a randomly oriented rod-like morphology, with the length and width of these nanorods ranging from 78 to 122 and from 9 to 13 nm. Moreover, the mechanical characterizations of the composite HZBT4 (80HAp-10TiC-5h-BN-5ZrO2) reveal a very high compressive strength (246 MPa), which is comparable to that of the steel (250 MPa), fracture toughness (14.78 MPa m1/2), and Young's modulus (1.02 GPa). In order to check the biocompatibility of the composites, numerous biological tests were also performed on different body organs of healthy adult Sprague-Dawley rats. This study suggests that the composite HZBT4 could not reveal any significant influence on the hematological, serum biochemical, and histopathological parameters. Hence, the fabricated composite can be used for several biological applications, such as bone implants, bone grafting, and bone regeneration.


Assuntos
Durapatita , Nanocompostos , Ratos , Animais , Durapatita/toxicidade , Durapatita/química , Ratos Sprague-Dawley , Materiais Biocompatíveis/toxicidade , Osso e Ossos , Nanocompostos/toxicidade
16.
Microbiology (Reading) ; 159(Pt 5): 913-923, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23475950

RESUMO

Escherichia coli FadR, a member of the GntR family of transcription factors, plays dual roles in fatty acid metabolism. FadR-DNA binding is inhibited by fatty acyl-CoAs, and thus FadR acts as a sensor of the fatty acid level in bacteria. We have identified FadR-binding sites in the upstream regions of genes showing altered expression after the disruption of fatty acid biosynthesis in Mycobacterium tuberculosis. A FadR homologue in M. tuberculosis, Rv0494, was identified, which binds to its operator in the upstream region of the kas operon. We have shown that FadRMt (Rv0494) directly binds to long-chain fatty acyl-CoA and that binding quenches the intrinsic fluorescence of the purified protein. FadR-DNA binding can be impaired by long-chain fatty acyl-CoA compounds. Overexpression of Rv0494 in Mycobacterium bovis BCG reduced the basal level expression of kas operon genes, thereby suggesting the repressor nature of this protein in fatty acid synthase II regulation. This is the first report, to the best of our knowledge, of a GntR/FadR family protein acting as a fatty acid-responsive transcriptional regulator in M. tuberculosis, suggesting a possible role for this protein in mycolic acid biosynthesis.


Assuntos
Proteínas de Bactérias/metabolismo , Ácidos Graxos/metabolismo , Família Multigênica , Mycobacterium tuberculosis/metabolismo , Fatores de Transcrição/metabolismo , Acil Coenzima A/metabolismo , Motivos de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sítios de Ligação , DNA Bacteriano/metabolismo , Regulação Bacteriana da Expressão Gênica , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/genética , Ácidos Micólicos/metabolismo , Ligação Proteica , Fatores de Transcrição/química , Fatores de Transcrição/genética
17.
Mol Biol Rep ; 40(11): 6271-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24057184

RESUMO

Type 2 diabetes mellitus (T2DM) is a metabolic pro-inflammatory disorder characterized by chronic hyperglycemia and increased levels of circulating cytokines suggesting a causal role of inflammation in its etiology. Polymorphism of cytokine genes including interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α) and interleukin-10 (IL-10) were studied in T2DM patients as well as in normal healthy controls. Genomic DNA was isolated from both T2DM patients and controls followed by quantification and genotyping by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using suitable primers. The genotypic, allelic and carriage rate frequency distribution in patients and controls were analyzed by SPSS (version 15.0). Odd ratios with 95 % confidence interval was determined to describe the strength of association by logistic regression model. Double and triple combinations of genotypes were analyzed by χ(2) test. Gene-gene interaction and linkage disequilibrium tests were performed using SHEsis software. Individually, IL-6, TNF-α and IL-10 did not show any association. In double combination, IL-6 -597 GA and TNF-α -308 GG genotypes increased the risk up to 21 times and in triple combination IL-6 -597 AA, TNF-α -308 GG and IL-10 -592 CA increased the risk of T2DM up to 314 times. In gene-gene interaction allele 'A' of all studied polymorphisms increased the risk of T2DM up to 1.41 times. Our results suggest that individuals having a haplotype combination of AA, GG and CA for IL-6, TNF-α and IL-10 gene polymorphisms will have higher susceptibility and be at greater risk of developing T2DM.


Assuntos
Diabetes Mellitus Tipo 2/genética , Estudos de Associação Genética , Interleucina-10/genética , Interleucina-6/genética , Polimorfismo Genético , Fator de Necrose Tumoral alfa/genética , Alelos , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/metabolismo , Frequência do Gene , Haplótipos , Humanos , Índia , Desequilíbrio de Ligação , Razão de Chances , Polimorfismo de Nucleotídeo Único
18.
J Proteomics ; 275: 104823, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36646275

RESUMO

PARP inhibitors are a potential class of chemotherapeutic drugs but PARP inhibitor response has not been explored systematically. We lack a specific understanding of the subset of the proteome preferentially modified in various cancers by PARP inhibitors. Implications of PARP inhibitor and PARP1 in cervical cancer treatment and resistance are not fully elucidated. We conducted a mass spectrometry-based proteomic analysis of cervical cancer Hela cells treated with olaparib. We aimed to identify the alteration in the protein signaling pathway induced by PARP inhibitors beyond the DNA damage response pathway. Our data demonstrate a significant reduction in PARP activity and enhanced cell death after olaparib treatment. We further observed articulated proteomic changes with a significant enrichment of proteins in diverse cellular processes. The differentially expressed proteins were predominantly associated with RNA metabolism, mRNA splicing, processing, and RNA binding. Our data also identified proteins that could probably contribute to survival mechanisms resulting in resistance to PARP inhibitors. Hence, we put forth the overview of proteomic changes induced by PARP inhibitor olaparib in cervical cancer cells. This study highlights the significant proteins modified during PARP inhibition and thus could be a probable target for combination therapies with PARP inhibitors in cervical cancer. SIGNIFICANCE.


Assuntos
Antineoplásicos , Neoplasias do Colo do Útero , Feminino , Humanos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Células HeLa , Proteômica , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , RNA
19.
Toxicol In Vitro ; 92: 105654, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37495164

RESUMO

Cigarette smoke is one of the leading causes of oxidative stress due to high levels of free radicals, which in turn leads to the degradation of alveolar cell walls and development of emphysema. Cigarette smoking has been linked to chronic bronchitis, Chronic Obstructive Pulmonary Disease (COPD) and lung cancer as well. The aim of the present study was to observe the effect of cigarette smoke extract (CSE) on TNF-α and MMPs mediated mucus hypersecretion in A549 cell line. The MTT experiments showed that CSE caused a dose-dependent decline in the level of viability of A549 cells. In addition, AO/PI and Mitotracker Red staining assays demonstrated that CSE caused the A549 cells to undergo apoptosis. This was determined by observing the reduction in mitochondrial membrane potential. CSE was found to be responsible for the formation of intracellular ROS, which was observed by DCFDA staining through fluorescence microscopy. Approximately 65% migration rate was decreased in 20% CSE exposed cells. CSE exposure led to the significantly increased mRNA levels of TNF-α, MMP-7, and MMP-12, in comparison to the control cells. Additionally, the expression of MUC5AC and MUC5B was provoked by CSE as well. Human epithelial cells are stimulated by TNF-α and MMPs secreted mucus, as shown by expression of MUC5AC and MUC5B. CSE could induce mucus in lungs through TNF-α and MMPs mediated pathways.


Assuntos
Fumar Cigarros , Doença Pulmonar Obstrutiva Crônica , Humanos , Fator de Necrose Tumoral alfa/metabolismo , Pulmão , Doença Pulmonar Obstrutiva Crônica/genética , Muco/metabolismo
20.
Gene ; 868: 147389, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-36963733

RESUMO

Cervical cancer (CaCx) is the malignancy of uterine cervix which induce by human papillomavirus (HPV) infections. HPV infection starts with the induction of double-stranded breaks by increasing oxidative stress and modulation of DNA repair pathways. Deficiency in DNA repair pathways and accumulation of DNA damage increases mutation rates resulting in genomic instability and cancer development. Patients with HPV-associated CaCx display increased sensitivity to cisplatin-based chemoradiotherapy (CRT) and improved survival rates. However, the cellular mechanisms responsible for this characteristic difference are unclear. Here, we have evaluated expression of DNA repair genes in peripheral blood cells and correlated them with treatment outcomes. A total of 211 study subjects includes in the study comprised 103 CaCx patients and 108 healthy controls. All the study subjects were analyzed for the expression profile of DNA repair genes by using real-time PCR (RT-PCR). The differentially expressed DNA repair gene was correlated with the treatment outcome of CRT. OGG1, XRCC2, XRCC3, XRCC4 and XRCC6 genes were found to be significant (P = 0.001) down-regulated as compared to controls. While XRCC5 and RAD51 showed significant up-regulated (P = 0.024 and 0.041) in CaCx patients. XRCC6 was associated (P = 0.033) with poor vital while up-regulated RAD51 showed slight association (P = 0.075) with better vital with an increased 2.96- and 2.33-fold risk in the study population. In the case of overall survival, down-regulated XRCC4 was associated (P = 0.042) with poor survival (27 months) with the least hazard ratio (0.56 HR). Down-regulated OGG1 involved BER, XRCC2 and XRCC3 in homologous recombination and XRCC4, XRCC5 and XRCC6 in Non-homologous end-joining repair, which showed a deficiency of DNA repair capacity resulting caused of an accumulation of DNA damage and genome instability. Impaired DNA repair gene expression is responsible for poor prognosis and survival in CaCx. Therefore, these gene expressions can be considered a potential prognostic, diagnostic and therapeutic biomarker for CaCx.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética , Reparo do DNA/genética , Dano ao DNA , Resultado do Tratamento , Proteínas de Ligação a DNA/genética
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