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1.
Mol Biol Rep ; 51(1): 286, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329638

RESUMO

BACKGROUND: Cellular resistance to cisplatin has been one of the major obstacles in the success of combination therapy for many types of cancers. Emerging evidences suggest that exosomes released by drug resistant tumour cells play significant role in conferring resistance to drug sensitive cells by means of horizontal transfer of genetic materials such as miRNAs. Though exosomal miRNAs have been reported to confer drug resistance, the exact underlying mechanisms are still unclear. METHODS AND RESULTS: In the present study, mature miRNAs secreted differentially by cisplatin resistant and cisplatin sensitive HepG2 cells were profiled and the effect of most significantly lowered miRNA in conferring cisplatin resistance when horizontally transferred, was analysed. we report miR-383 to be present at the lowest levels among the differentially abundant miRNAs expressed in exosomes secreted by cisplatin resistant cells compared to that that of cisplatin sensitive cells. We therefore, checked the effect of ectopic expression of miR-383 in altering cisplatin sensitivity of Hela cells. Drug sensitivity assay and apoptotic assays revealed that miR-383 could sensitise cells to cisplatin by targeting VEGF and its downstream Akt mediated pathway. CONCLUSION: Results presented here provide evidence for the important role of miR-383 in regulating cisplatin sensitivity by modulating VEGF signalling loop upon horizontal transfer across different cell types.


Assuntos
Cisplatino , MicroRNAs , Humanos , Cisplatino/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Células HeLa , Fator A de Crescimento do Endotélio Vascular/genética , MicroRNAs/genética
2.
Cureus ; 15(7): e41336, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37546068

RESUMO

Background The smoke inhaled by a nonsmoker from the smoldering end of a cigarette is referred to as passive smoke. The nicotine present in smoke is known to cause tissue damage and alter the enzymatic composition of the body. Alkaline phosphatase (ALP) is a group of intracellular hydrolytic enzymes known to partake in cellular metabolism. ALP levels are affected by smoking as well as passive smoking (PS) with a change in the pH of the oral cavity. The association of salivary alkaline phosphatase (S-ALP) levels in different age groups, gender, and times of exposure is not thoroughly explored yet, which was the primary aim of this study. Material and methods A total of 64 samples were collected from passive smokers and non-smokers. Unstimulated saliva (2-2.5 mL) was collected from each subject after obtaining their consent, followed by centrifuging and mixing with ALP reagent in a semi-autoanalyzer to obtain the S-ALP levels. Results Higher S-ALP levels were seen in passive smokers (34.70 IU/L) compared to healthy individuals (12 IU/L), which came to be statistically significant (p<0.01). S-ALP levels, when compared to different age groups and gender, were statistically insignificant (p>0.05). However, higher levels were seen in association with time of exposure in passive smokers where the data was statistically significant (p<0.01), suggesting tissue damage possibly due to oxidative stresses and tissue inflammation on continuous exposure for a minimum of 30-60 minutes daily as per our study. Conclusion Significantly high levels of S-ALP were found in passive smokers in comparison to non-smokers. This suggests that passive smoking has negative effects on the body tissues. Age, gender, and time of exposure of a non-smoker to tobacco smoke can lead to alterations in S-ALP levels. High levels of S-ALP were seen in individuals with prolonged exposure to tobacco smoke on a daily basis. Salivaomics can thus be used as a non-invasive, economical, and accurate alternative in tissue damage diagnosis.

3.
Sci Rep ; 13(1): 11052, 2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37422487

RESUMO

The considerable improvement of technology produced for various applications has resulted in a growth in data sizes, such as healthcare data, which is renowned for having a large number of variables and data samples. Artificial neural networks (ANN) have demonstrated adaptability and effectiveness in classification, regression, and function approximation tasks. ANN is used extensively in function approximation, prediction, and classification. Irrespective of the task, ANN learns from the data by adjusting the edge weights to minimize the error between the actual and predicted values. Back Propagation is the most frequent learning technique that is used to learn the weights of ANN. However, this approach is prone to the problem of sluggish convergence, which is especially problematic in the case of Big Data. In this paper, we propose a Distributed Genetic Algorithm based ANN Learning Algorithm for addressing challenges associated with ANN learning for Big data. Genetic Algorithm is one of the well-utilized bio-inspired combinatorial optimization methods. Also, it is possible to parallelize it at multiple stages, and this may be done in an extremely effective manner for the distributed learning process. The proposed model is tested with various datasets to evaluate its realizability and efficiency. The results obtained from the experiments show that after a specific volume of data, the proposed learning method outperformed the traditional methods in terms of convergence time and accuracy. The proposed model outperformed the traditional model by almost 80% improvement in computational time.


Assuntos
Big Data , Redes Neurais de Computação , Algoritmos
4.
Sci Rep ; 13(1): 9981, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340060

RESUMO

In this paper, we study Multiple slit diffraction and n- array linear antennae in negative refractive index material. We show that the evanescent wave plays a vital role in the near-field term. The evanescent wave grows significantly, unlike in conventional materials, and satisfies a novel kind of convergence known as Cesàro convergence. We calculate the intensity of multiple slits and the antenna's amplification factor (AF) in terms of the Riemann zeta function. We further demonstrate that the Riemann zeta function gives rise to additional nulls. We deduce that all the diffraction scenarios in which the traveling wave satisfies the geometric series in the medium of the positive refractive index will enhance the evanescent wave, which satisfies Cesàro convergence in the medium of the negative refractive index.

5.
Appl Biochem Biotechnol ; 193(1): 238-256, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32894388

RESUMO

α-Galactosidases hold immense potential due to their biotechnological applications in various industrial and functional food sectors. In the present study, soluble and covalently cross-linked aggregated forms of a low molecular weight, thermo-labile α-galactosidase from Vigna mungo (VM-αGal) seeds were immobilized onto chitosan-coated magnetic nanoparticles for improved stability and repeated usage by magnetic separation. Parameters like precipitants (type, amount, and ratio), glutaraldehyde concentration, and enzyme load were optimized for the preparation of chitosan-coated magnetic nanocomposites of cross-linked VM-αGal (VM-αGal-MC) and VM-αGal (VM-αGal-M) resulted in 100% immobilization efficiency. Size and morphology of VM-αGal-M were studied through dynamic light scattering (DLS) and scanning electron microscopy (SEM), while Fourier transform infrared spectroscopy (FTIR) was used to study the chemical composition of VM-αGal-MC and VM-αGal-M. VM-αGal-MC and VM-αGal-M were found more active in a broad range of pH (3-8) and displayed optimal temperatures up to 25 °C higher than VM-αGal. Addition of non-ionic detergents (except Tween-40) improved VM-αGal-MC activity by up to 44% but negatively affected VM-αGal-M activity. Both VM-αGal-MC (15% residual activity after 21 min at 85 °C, Ed 92.42 kcal/mol) and VM-αGal-M (69.0% residual activity after 10 min at 75 °C, Ed 39.87 kcal/mol) showed remarkable thermal stability and repeatedly hydrolyzed the substrate for 10 cycles.


Assuntos
Enzimas Imobilizadas/química , Campos Magnéticos , Nanocompostos/química , Proteínas de Plantas/química , Vigna/enzimologia , alfa-Galactosidase/química , Estabilidade Enzimática , Temperatura Alta , Solubilidade
6.
J Forensic Odontostomatol ; 38(2): 22-39, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-33174535

RESUMO

The goal of long term research on age assessment is to focus on the strengths and weaknesses of existing reliable methods of age estimation. In cases of age estimation when all teeth are present, maximum accuracy can be obtained using a 7 tooth model. Demirjian's system and Willems models require all seven mandibular teeth in the lower left quadrant for age assessment. Unfortunately, these methods cannot be applied in children with hypodontia. In 2019, Bedek et al., from Croatia, developed new models of age estimation based on a combination of one to seven mandibular teeth. In the present study, we tested the accuracy of the newly developed models for age estimation in South Indian children. Tested in parallel with Willems models, the accuracy of the new models was tested in terms of mean difference, mean absolute error (MAE) and percentage of correct estimations within intervals of +0.5 and +1 years. In terms of mean difference between chronological age (CA) and estimated dental age (DA), all models along with Willems models have underestimated the CA except Bedek et al's 6 tooth model where overestimation of CA was seen in boys. For MAE and percentage of correct estimations, the new models performed better than Willems models. With regards to our results, it can be concluded that the new models for dental age calculation are accurate and suitable. Therefore, we may encourage their use for age estimation in South Indian children, particularly in individuals with hypodontia or when multiple teeth are missing.


Assuntos
Determinação da Idade pelos Dentes , Dente , Adolescente , Criança , Croácia , Humanos , Masculino , Radiografia Panorâmica , Calcificação de Dente
7.
Adv Biosyst ; 4(1): e1900224, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32293122

RESUMO

A set of genetically engineered isogenic cell lines is developed to express either folate receptor alpha or mesothelin, and a control cell line negative for both antigens. These cell lines also express fluorescent and bioluminescent reporter transgenes. The cell lines are used to authenticate specificity and function of a T-cell biofactory, a living vector that is developed to express proportionate amounts of engineered proteins upon engaging with disease cells through their specific antigenic biomarkers. The engineered cell lines are also used to assess the cytolytic function and specificity of primary T cells engineered with chimeric antigen receptors; and the specificity of monoclonal antibodies. The strategy described can be used to generate other cell lines to present different disease-specific biomarkers for use as quality control tools.


Assuntos
Engenharia Celular/métodos , Engenharia Genética/métodos , Neoplasias Ovarianas/genética , Receptores de Antígenos Quiméricos/genética , Linfócitos T , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Ovarianas/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo
8.
Cell Signal ; 38: 146-158, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28709644

RESUMO

Recent studies indicate that horizontal transfer of genetic material can act as a communication tool between heterogenous populations of tumour cells, thus altering the chemosensitivity of tumour cells. The present study was designed to check whether the horizontal transfer of miRNAs released by cisplatin resistant (Cp-r) Hepatocarcinoma cells can alter the sensitivity of cervical cancer cells. For this exosomes secreted by cisplatin resistant and cisplatin sensitive HepG2 cells (EXres and EXsen) were isolated and characterised. Cytotoxicity analysis showed that EXres can make Hela cells resistant to cisplatin. Analysis of miR-106a/b levels in EXres and EXsen showed that their levels vary. Mechanistic studies showed that miR-106a/b play an important role in EXsen and EXres mediated change in chemosensitivity of Hela cells to cisplatin. Further SIRT1 was identified as a major target of miR-106a/b using in silico tools and this was proved by experimentation. Also the effect of miR-106a/b in chemosensitivity was seen to be dependent on regulation of SIRT1 by miR-106a/b. In brief, this study brings into light, the SIRT1 dependent mechanism of miR-106a/b mediated regulation of chemosensitivity upon the horizontal transfer from one cell type to another.


Assuntos
Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Técnicas de Transferência de Genes , Neoplasias Hepáticas/genética , MicroRNAs/genética , Neoplasias do Colo do Útero/genética , Sequência de Bases , Exossomos/efeitos dos fármacos , Exossomos/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Modelos Biológicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Neoplasias do Colo do Útero/patologia
9.
Mol Cell Biochem ; 423(1-2): 197-206, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27704463

RESUMO

MMP9 is a member of the family of zinc-containing endopeptidases which degrade various components of the extracellular matrix, thereby regulating matrix remodeling. Since matrix remodeling plays an important role during growth and progression of cancer and considering the fact that, tumor cells switch to aerobic glycolysis as its major energy source, this study was designed to analyze if partial inhibition of glycolysis (the major energy pathway during hypoxia) can be used as a means to control matrix remodeling in terms of MMP9 activity and expression. For this, human epithelial carcinoma cells were treated with glycolytic inhibitor, 2-deoxy glucose (2DG) at sub-lethal concentrations followed by analysis of the expression and activity of MMP2 and MMP9. The experimental findings demonstrate that exposure of cancer cells to glycolytic inhibitor at concentration that does not induce ER stress, downregulates the activity and expression of MMP9 without affecting the expression levels and activity of MMP2. Further mechanistic analysis revealed that the regulation of MMP9 was mediated in a SIRT-1 dependent mechanism and did not alter the NFkB signaling pathway. The overall results presented here, therefore suggest that the use of glycolytic inhibitor, 2DG at concentration that do not affect cell viability or induce ER stress can be an effective strategy to control matrix remodeling.


Assuntos
Desoxiglucose/farmacologia , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Células HeLa , Humanos , Metaloproteinase 2 da Matriz/metabolismo
10.
Curr Drug Deliv ; 12(6): 703-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25751659

RESUMO

The present research was aimed to formulate aceclofenac transemulgel using Aloe vera as gel base. The prepared formulations were subjected to physical characterization, in-vitro and in-vivo assessment. Aceclofenac, a hydrophobic potential non steroidal anti inflammatory drug, causes ulceration upon chronic oral administration, could be formulated into transemulgel to enhance therapeutic efficacy and to lower the unwanted side effects. The transemulgel was prepared from aqueous Aloe vera gel and aceclofenac emulsion. The prepared transemulgel was evaluated for its pH, viscosity, drug content, skin irritation, in-vitro diffusion and accelerated stability studies. The prepared aceclofenac-Aloe vera tranemulgel and commercial aceclofenac gel were subjected to pharmacodynamic studies in albino rats of Wistar strain employing carrageenan induced left hind paw edema method to assess the anti-inflammatory effect. The transemulgel showed a pH of 6.78 and viscosity of 18 cps. In-vitro diffusion data revealed better permeation characteristics. Topical application of formulation found no skin irritation. Stability study has proved the integrity of the formulation. The prepared aceclofenac Aloe vera transemulgel showed better in-vitro drug release when compared with the commercial aceclofenac gel formulation. Anti-inflammatory activity in treated rats showed the significant paw volume reduction at p<0.05 compared with that of control. Thus, it is concluded that aceclofenac, a potential non steroidal anti inflammatory drug, showed high therapeutic efficiency when formulated into transemulgel using aqueous Aloe vera as gel base.


Assuntos
Aloe/química , Anti-Inflamatórios não Esteroides/administração & dosagem , Diclofenaco/análogos & derivados , Inflamação/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/farmacologia , Química Farmacêutica/métodos , Diclofenaco/administração & dosagem , Diclofenaco/farmacocinética , Diclofenaco/farmacologia , Modelos Animais de Doenças , Estabilidade de Medicamentos , Edema/tratamento farmacológico , Edema/patologia , Géis , Concentração de Íons de Hidrogênio , Inflamação/patologia , Masculino , Ratos , Ratos Wistar , Absorção Cutânea , Viscosidade
11.
Artigo em Inglês | MEDLINE | ID: mdl-23254735

RESUMO

Trichilemmal cyst, also known as "pilar cyst," is a benign cyst containing keratin and its breakdown products with a wall resembling external root sheath of hair. It occurs mostly in females as a solitary firm nodule over scalp. Occurrence of multiple trichilemmal cysts in areas other than scalp is extremely rare. We are reporting a case of a 40-years-old female who presented with multiple calcified trichilemmal cysts in multicentric distribution associated with alopecia universalis. Similar complaints were present in elder sister of the patient, indicating a genetic background. Multicentric distribution of trichilemmal cysts, calcification, familial occurrence, and association with alopecia universalis seen in our case are all rare and intriguing features.


Assuntos
Alopecia/genética , Cisto Epidérmico/patologia , Adulto , Alopecia/complicações , Alopecia/patologia , Nádegas , Cisto Epidérmico/complicações , Feminino , Antebraço , Humanos , Couro Cabeludo , Irmãos
12.
Asian Pac J Trop Biomed ; 2(11): 895-900, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23569867

RESUMO

OBJECTIVE: To study the antioxidant efficacy of Commiphora mukul (C. mukul) gum resin ethanolic extract in streptozotocin (STZ) induced diabetic rats. METHODS: THE MALE WISTAR ALBINO RATS WERE RANDOMLY DIVIDED INTO FOUR GROUPS OF EIGHT ANIMALS EACH: Control group (C), CM-treated control group (C+CMEE), Diabetic control group (D), CM- treated diabetic group (D+CMEE). Diabetes was induced by intraperitoneal injection of STZ (55 mg/kg/ bwt). After being confirmed the diabetic rats were treated with C. mukul gum resin ethanolic extract (CMEE) for 60 days. The biochemical estimations like antioxidant, oxidative stress marker enzymes and hepatic marker enzymes of tissues were performed. RESULTS: The diabetic rats showed increased level of enzymatic activities aspartate aminotransaminase (AST), alanine aminotransaminase (ALT) in liver and kidney and oxidative markers like lipid peroxidation (LPO) and protein oxidation (PO) in pancreas and heart. Antioxidant enzyme activities were significantly decreased in the pancreas and heart compared to control group. Administration of CMEE (200 mg/kg bw) to diabetic rats for 60 days significantly reversed the above parameters towards normalcy. CONCLUSIONS: In conclusion, our data indicate the preventive role of C. mukul against STZ-induced diabetic oxidative stress; hence this plant could be used as an adjuvant therapy for the prevention and/or management of diabetes and aggravated antioxidant status.


Assuntos
Antioxidantes/farmacologia , Commiphora/química , Diabetes Mellitus Experimental/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alanina Transaminase/análise , Animais , Antioxidantes/química , Aspartato Aminotransferases/análise , Coração/efeitos dos fármacos , Fígado/metabolismo , Masculino , Miocárdio/química , Miocárdio/enzimologia , Miocárdio/metabolismo , Oxirredutases/análise , Pâncreas/química , Pâncreas/efeitos dos fármacos , Pâncreas/enzimologia , Pâncreas/metabolismo , Extratos Vegetais/química , Ratos , Ratos Wistar
13.
Indian Dermatol Online J ; 2(1): 40-2, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23130218
14.
Genes Cancer ; 1(1): 69-80, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20634902

RESUMO

Activating mutations in CDK4 and inactivation of its key kinase inhibitor, p16INK4A, have been implicated in the genesis and progression of human cancer. Previous work has demonstrated that CDK4 expression is required for Neu-induced but not Wnt-induced breast tumorigenesis in mice. However, the role that CDK4 plays in ras-mediated breast tumor development is not well defined. To gain an understanding of the role of Cdk4 in ras-induced breast tumorigenesis, MMTV-v-Ha-ras transgenic mice were bred with Cdk4(+/neo) and Cdk4(R24C/R24C) mice to generate Cdk4(neo/neo):MMTV-v-Ha-ras, Cdk4(+/+):MMTV-v-Ha-ras, and Cdk4(R24C/R24C):MMTV-v-Ha-ras mice. The studies presented here demonstrate that Cdk4 expression is essential for Ras-mediated breast tumorigenesis. Surprisingly, the results also show that coexpression of mutant ras and Cdk4R24C genes in breast epithelial cells leads to an activation of senescent pathways that delay tumorigenesis. Analysis of the phosphorylated form of H2AX, a marker for DNA damage, indicated its increased presence in the tumors of Cdk4(R24C/R24C):MMTV-v-Ha-ras mice. These observations indicate that the increased apoptosis and senescence seen in breast tumors of these mice might be due to increased DNA damage response in cells expressing activated forms of ras and Cdk4(R24C).

15.
Cancer Res ; 65(22): 10174-8, 2005 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16288002

RESUMO

Previous work has shown that cyclin D1 expression is required for neu- and ras-induced, but not wnt- or c-myc-induced, breast tumorigenesis in mice. Although cyclin D1 binds and activates cyclin-dependent kinase 4 (Cdk4), thereby mediating activation of a program of E2F-dependent gene expression, it has been suggested that the oncogenic activities of cyclin D1 are independent of Cdk4. To determine whether Cdk4 expression is required for breast tumorigenesis in mice, we have generated compound mice ectopically expressing the neu or wnt oncogenes in the mammary glands of wild-type and Cdk4-/- mice. Our results show that Cdk4 expression is required for efficient neu-induced tumorigenesis but is dispensable for wnt-induced breast tumorigenesis. In contrast to results previously observed in the mammary glands of cyclin D1-/- virgin females, our results show defects in mammary gland development in Cdk4-/- virgin females, suggesting differences in compensatory mechanisms in the absence of either subunit of the cyclin D1/Cdk4 complex. These results suggest that drugs targeted to inhibit Cdk4 activities could be developed to specifically treat certain breast tumors as Cdk4 is not essential for viability.


Assuntos
Transformação Celular Neoplásica/metabolismo , Quinase 4 Dependente de Ciclina/biossíntese , Genes erbB-2/fisiologia , Neoplasias Mamárias Experimentais/enzimologia , Animais , Transformação Celular Neoplásica/genética , Quinase 2 Dependente de Ciclina/biossíntese , Quinase 2 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/deficiência , Quinase 4 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/biossíntese , Quinase 6 Dependente de Ciclina/genética , Feminino , Masculino , Glândulas Mamárias Animais/enzimologia , Glândulas Mamárias Animais/crescimento & desenvolvimento , Neoplasias Mamárias Experimentais/genética , Camundongos , Camundongos Transgênicos , Proteína Wnt1/genética
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