Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Lancet ; 403(10443): 2483, 2024 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-38823405
2.
Br J Oral Maxillofac Surg ; 62(1): 76-82, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38092568

RESUMO

Oral submucous fibrosis (OSMF) is a premalignant condition associated with chewing areca nut and tobacco products. We observed increased fluoride levels in some OSMF-endemic regions,and the observation suggested that fluoride exposure may contribute to its pathogenesis. This study aimed to assess the fluoride content of various smokeless tobacco items as a potential influencing source. Fluoride concentration was analysed in commercial areca nut products, including gutkha, pan masala, and raw areca nut, along with tobacco, slaked lime, and catechu samples from Karnataka, India. Fluoride was measured using alkali fusion and the ion selective electrode method. All products showed high fluoride, with catechu having the highest mean concentration at 51.20 mg/kg, followed by tobacco, gutkha, pan masala, processed areca nut, and raw areca nut. Fluoride was also elevated in soil, but not in water. The findings demonstrate substantial fluoride levels in popular types of smokeless tobacco, and highlight an overlooked source of exposure among consumers of gutkha, pan masala and similar oral tobacco-products. The fluoride content warrants an investigation of potential links with the occurrence and severity of OSMF.


Assuntos
Fibrose Oral Submucosa , Tabaco sem Fumaça , Humanos , Fluoretos , Areca , Projetos Piloto , Nozes , Índia
3.
Med J Malaysia ; 76(1): 80-86, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33510114

RESUMO

This work investigates the Musa Paradisiaca plant and its tepal extracts. The research findings show that the tepal extracts of M. Paradisiaca contain high phytochemical activity. Hence we can conclude that these plants have a number of beneficial properties. Phytochemical analysis concludes that the plant is rich in flavonoids, phenolic compounds, tannins, terpenoids, and phytosterol. In the current work, silver nanoparticles (AgNPs) have revealed the antioxidant properties of M. Paradisiaca. The results show that the methanolic extracts of these tepals exhibit antioxidant potential and are also sources of natural antioxidant compounds, though comparatively, AgNPs have shown the best antioxidant activity. This work investigates the link between the ethnopharmacological statements and the bioactive constituents found in M. Paradisiaca toward all probable markers for cervical cancer via in vivo studies and molecular docking, to form a pharmacophore setting for the active target. However, most of the mechanisms of action of herbal medicines are not in total agreement, and the information collected from their traditional remedies over the years must not be neglected. Hence, it is sensible to investigate the options available in herbal medicine for cancer progression. Biosynthesised AgNPs are principally spherical and nanosized. It was also found that tepalmediated AgNPs exhibit excellent antimicrobial efficacy against tested human pathogens. This green method can be used as a better alternative source than the chemical fabrication of nanomaterials and the biosynthesised nanoparticles can be used in antibacterial medicines. The methanolictepal extract of M. Paradisiaca with AgNPs displayed proficient antidiabetic properties in the diabetes rat model and so could have a possible development for medical use in the future.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Musa , Extratos Vegetais , Animais , Antibacterianos/farmacologia , Humanos , Hipoglicemiantes/farmacologia , Simulação de Acoplamento Molecular , Musa/química , Extratos Vegetais/farmacologia , Ratos , Prata
4.
Med Hypotheses ; 144: 110235, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33201802

RESUMO

Carcinogens play a key role in cancer initiation. Conventional theories support the concept of genetic changes inducing tumorigenesis through proteomics and metabolomics which lead to cancer development. Current research provides evidence that metabolic genes may be altered long before mutation of tumour suppressor genes, strongly suggesting that metabolic changes may be preceding the changes seen at a genetic level. Since cancer has long been known to occur through gene regulation, an impaired cellular respiration without utilizing mitochondrial function has been an area of active interest. We hypothesize the activity of carcinogens as electron acceptors to disrupt the normal glycolysis cycle happening in a cell by acting as positive ligands. The continuous restoration of NAD+ to cytosol by oxidation of NADH with carcinogen as electron acceptor creates a metabolic pathway to assist in the carcinogenic process. This metabolic pathway continues through an adaptive process, supplemented by pyruvate converting to lactate providing a constant pool of NAD+ to continue the glycolytic pathway. We also hypothesize that carcinogenesis occurs as a precursor to metabolic stress which may promote altered genetic and protein expression causing aberrant epigenetic and cell signaling pathways.


Assuntos
Carcinógenos , Elétrons , Carcinogênese , Carcinógenos/toxicidade , Glicólise , Humanos , Oxirredução
5.
Med J Malaysia ; 75(6): 677-684, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33219177

RESUMO

INTRODUCTION: Brassica oleracea var acephala was studied for preliminary phytochemical screening. The results showed that the ethanolic crude extract of the leaf contain high phytochemical activity hence B.oleracea var acephala is rich in flavonoids, phenolic compounds, carbohydrates and phytosterols. MATERIALS AND METHODS: The ethanolic extract was used to synthesise copper nanoparticles. The copper nanoparticles were successfully synthesised from copper sulphate solution which was identified by the colour change from dark green colour of the extract. Thus the B.oleracea var acephala is a good source to synthesis copper nanoparticles. The synthesised copper nanoparticles were characterised using Scanning Electron Microscope (SEM) analysis. The SEM image displayed the high-density nanoparticles synthesised by leaf extracts and that the nanoparticles were crystals in shape. RESULTS: The copper nanoparticles (CNP) bind to the leaf extract. B.oleracea var acephala also has shown the antimicrobial and antioxidant activity. A comparative study was done between ethanolic its crude extract and nanoparticles. Both extracts exhibited zone of inhibition and better antioxidant potential but the CuNPs shows major zone of inhibition and showed more antioxidant activity. Anticancer activity of B.oleracea var acephala against Cervical HeLa cell line was confirmed using ethanolic crude extract and CNP. The results showed that HeLa cells proliferation was inhibited with increasing concentration of ethanolic crude extract and copper nanoparticles. From the results, it was seen that percentage viability of the cancer cells decreased with increased concentration of the samples whereas cytotoxicity against HeLa cell lines increased with the increased concentration of the samples. CONCLUSION: Thus B.oleracea var acephala possesses anticancer activity against HeLa cell lines.


Assuntos
Antibacterianos , Antineoplásicos Fitogênicos/farmacologia , Brassica , Nanopartículas , Extratos Vegetais , Antibacterianos/farmacologia , Brassica/química , Cobre , Células HeLa , Humanos , Extratos Vegetais/farmacologia , Folhas de Planta/química
6.
Rev Sci Instrum ; 91(10): 105108, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33138572

RESUMO

As per the voices in the precision manufacturing industries, the machining of brittle materials such as glass and diamond is intricate owing to their thermo-mechanical properties. Machining of the brittle material with a localized heating method produced softness in the work material during the operation, resulting in microcracks and voids on the finished surface due to thermal stresses. Such pressing issues are solved by dry machining with bulk heating. The objective of the present research is to develop a sophisticated lab-made portable multipurpose heating setup for enabling various potent applications such as machining, elevated temperature scratch and indentation tests, and grinding, among other things, on hard and brittle materials. The mentioned process is done by softening the material with preheating of the samples. The overall dimensions of the developed setup are 105 × 150 × 53 mm3. This setup has been evaluated at different temperatures of the 45S5 bioglass sample surface up to 426 °C and is capable of holding and heating the samples.

10.
Oral Oncol ; 88: 27-28, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30616793
12.
Indian J Surg Oncol ; 9(1): 35-38, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29563732

RESUMO

The incidence of small differentiated thyroid carcinomas is increasing worldwide in the recent years, especially tumours of size less than 2 cm in diameter. In this study, we have analysed the patterns of behaviour of small-sized thyroid carcinomas (<2 cm, T1 tumours) in comparison with large-sized thyroid carcinomas. This is a retrospectively analysed data of patients with thyroid carcinoma. The following parameters were analysed: distribution with regard to age, sex and the presence of metastasis based on radioiodine scan. The following histopathological details were collected: maximal tumour diameter, extrathyroidal extension and lymphovascular invasion. Out of 152 patients, 39 patients were excluded due to the non-availability of complete details. Among the 113 patients of thyroid carcinomas, 43 patients (28%) were presented with small-sized tumours (measuring less than 2 cm). In small-sized thyroid tumours, 21.6% showed extrathyroidal extension. 2.7% of the small-sized thyroid carcinomas showed perineural invasion as compared to 6.3% of the large-sized thyroid carcinomas. Twenty percent of the small-sized thyroid carcinomas showed lymphovascular emboli. 51.2% of the small-sized thyroid carcinomas were presented with nodal metastasis as compared to 40% of the large-sized thyroid carcinomas. 57.5% of the small-sized thyroid carcinomas showed extracapsular extension as compared to 57.8% of the large-sized thyroid carcinomas. Despite small size, thyroid carcinomas have properties to behave aggressively as comparable to large-sized thyroid carcinomas. Taking the above facts into account, the small thyroid cancers should be treated with considerable caution as large thyroid cancers, especially since we have limited tools to predict the preoperative poor prognostic factors.

13.
Chin J Integr Med ; 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28914437

RESUMO

OBJECTIVE: To assess the beneficial potential of ethanolic extract of avocado fruit on abnormal carbohydrate metabolic key enzymes in hepatic and renal tissues in streptozotocin (STZ) induced hyperglycemic albino rats. METHODS: Twenty-four male albino rats were randomly divided into four groups with six in each group by simple random sampling method. Group 1 as control rats; Group 2 as STZ induced diabetic rats; Group 3 as diabetic rats treated with avocado fruit extract (AFE), 300 mg/kg as aqueous suspension orally for 30 days; Group 4 as diabetic rats treated with gliclazide (5 mg/kg) in aqueous solution orally for 30 days. The rats were fasted overnight and sacrificed by cervical dislocation and the blood was collected for various biochemical analysis and excision of hepatic and kidney were done for histological analysis. Levels of fasting blood glucose, plasma insulin and glycosylated hemoglobin were estimated. The activities of key enzymes in carbohydrate metabolism such as hexokinase, pyruvate kinase, glucose-6- phosphatase, fructose-1, 6-bisphosphatase, glucose-6-phosphate dehydrogenase, glycogen synthase and glycogen phosphorylase were assayed by standard methods described in the methodology. RESULTS: Oral administration of AFE significantly improved the altered levels of blood glucose, plasma insulin, glycosylated hemoglobin, and modulated the activities of carbohydrate metabolizing enzymes (P<0.05, respectively). The glycogen content in hepatic tissues was significantly increased in diabetic rats treated with AFE (P<0.05, respectively). CONCLUSION: AFE plays a pivotal role to maintain normoglycemia in diabetes by modulating the activities of carbohydrate metabolic enzymes.

14.
Chin J Integr Med ; 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28914438

RESUMO

OBJECTIVE: To assess the modulatory impact of alcoholic extract of fruit of Mengkudu (AEFM, Morinda citrifolia L., Rubiaceae) on renal oxido-lipidemic stress in hypercholesterolemic albino rats. METHODS: Twenty-four male albino rats were randomly divided into four groups with six rats in each group: group I as control, group II fed with hypercholesterolemic diet (HCD) for 45 days (4% cholesterol and 1% cholic acid), Group III rats fed with HCD for 45 days + AEFM (300 mg/kg body weight/day orally) for last 30 days and group IV normal rats fed AEFM alone. The blood was collected using ethylenediamine tetraacetic acid (EDTA) as an anticoagulant for various biochemical analysis, and excision of kidney was done for histological analysis. RESULTS: The levels of total cholesterol (TC), triacylglycerol (TG), phospholipids (PLs), renal functional parameters and lipid peroxidation products were markedly mitigated in AEFM treated hypercholesterolemic rats (group III) compared to group I (P<0.01). Activities of both enzymic and non-enzymic free radical scavenging factors were significantly increased in group III compared to group I (P<0.01). In group III the mRNA levels of interstitial endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) genes were obviously up-regulated (P<0.01) and down-regulated in (P<0.05) compared with group I. Histomorphological observations also exhibited similar as in group III AEFM commendably protects the renal tissues compared with group I (P<0.01). CONCLUSION: AEFM can act as nephroprotective agent by attenuating the renal oxidative stress, lipid levels as well as regulating NOS level and by this means protects the kidney in hypercholesterolemic induced nephropathy experimental rats.

15.
Indian J Surg Oncol ; 8(2): 249-252, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28546733

RESUMO

Carotid body tumours are rare and mostly benign neoplasm. They are slow growing but can evade or exert pressure on neighbouring important neurovascular structures. Hence, surgical resection remains the treatment modality of choice for large tumours partially or completely encasing the carotid arteries. But the surgical resection of these tumours with minimum morbidity is challenging because of their highly vascular nature. Earlier literature has dealt with various aspects of management of carotid body tumours including classification, morbidity, work-up, embolisation and extent of resection. However, the options in techniques of dissection for carotid body tumours have not been elaborated much. Here, we describe a stepwise dissection technique of carotid body tumours from the internal carotid towards the external carotid artery. This surgical technique, named as "the internal to external (INT-EX) technique", provides better control of bleeding during the surgery, ease of dissection and lesser post-operative morbidity.

16.
J Clin Pharm Ther ; 37(3): 313-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21916910

RESUMO

WHAT IS KNOWN AND OBJECTIVE: CYP2C19*17 allele increases the metabolic activity of CYP2C19 resulting in decreased therapeutic levels of CYP2C19 substrates. There exist inter-ethnic differences in the distribution of this allele. The present study was aimed at establishing the allele and genotype frequencies of CYP2C19*17 in a South Indian Tamilian population. Furthermore, we describe the haplotype structure of the three common variant alleles of CYP2C19 in the Tamilian population. METHODS: Two hundred and six subjects of South Indian Tamilian origin were genotyped for CYP2C19*17 allele by nested polymerase chain reaction and restriction fragment length polymorphism. A subset of 87 subjects were also genotyped for CYP2C19*2 and CYP2C19*3 alleles. After ascertaining linkage disequilibrium (LD), haplotypes were constructed. Allele and genotype frequencies, LD pattern and haplotype frequency were compared with those of the HapMap populations. RESULTS AND DISCUSSION: The CYP2C19*17 allele frequency in the Tamilian population (n = 206) was found to be 19·2% (95% CI: 15·4 - 20·3). The CYP2C19*2 allele frequency (n = 87) was found to be 40·2% (95% CI: 32·9 - 47·5), whereas the CYP2C19*3 allele was not detected in the study subjects (n = 97). The high frequency of the CYP2C19*17 allele in the study population has resulted in a revision of frequencies for CYP2C19*1/*2 (31·0%) and CYP2C19*1/*1 (16·1%) genotypes in the Tamilian population. We also observed significant differences in haplotype structure and frequencies of these variant alleles in the HapMap population compared to Tamilian population. WHAT IS NEW AND CONCLUSION: CYP2C19*17 allele is present at high frequency in the Tamilian population. This study also demonstrates the need for reassessment of wild-type allele frequencies in view of CYP2C19*17 allele. The estimated high frequency of CYP2C19*17 allele will aid in genotype-phenotype association studies in the Tamilian population. Further genotype-phenotype association studies are required to evaluate the clinical utility of this allele in South Indians.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Povo Asiático/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Alelos , Hidrocarboneto de Aril Hidroxilases/metabolismo , Biotransformação , Citocromo P-450 CYP2C19 , Éxons , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Índia , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , Regiões Promotoras Genéticas , Adulto Jovem
18.
Mol Cell Biochem ; 358(1-2): 121-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21713411

RESUMO

Quercitrin, a bio flavonoid, was investigated for its antioxidant potential in streptozotocin (STZ)-induced diabetic rats. Rats were induced diabetic by a single intraperitoneal injection of streptozotocin (50 mg/kg). The levels of fasting plasma glucose and insulin were estimated. Lipid peroxidative products and antioxidants were estimated in pancreas, liver, and kidney. Histopathological studies were carried out in these tissues. A significant (P < 0.05) increase in the levels of fasting plasma glucose and lipid peroxidative products (thiobarbituric acid reactive substances and lipid hydroperoxides) and a significant (P < 0.05) decrease in plasma insulin, enzymic antioxidants (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase), and nonenzymic antioxidants (reduced glutathione, vitamin C, and E) in diabetic pancreas, liver, and kidney were observed. Oral administration of quercitrin (30 mg/kg) for a period of 30 days significantly (P < 0.05) decreased fasting plasma glucose, increased insulin levels, and improved the antioxidant status of diabetic rats by decreasing lipid peroxidative products and increasing enzymic and nonenzymic antioxidants. Normal rats treated with quercitrin (30 mg/kg) showed no significant (P < 0.05) effect on any of the parameters studied. Histopathological studies of the pancreas, liver, and kidney showed the protective role of quercitrin. Thus, our study clearly shows that quercitrin has antioxidant effect in STZ-induced experimental diabetes.


Assuntos
Antioxidantes/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Flavonoides/uso terapêutico , Quercetina/análogos & derivados , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/patologia , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Jejum/sangue , Comportamento Alimentar/efeitos dos fármacos , Flavonoides/farmacologia , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Insulina/sangue , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Quercetina/farmacologia , Quercetina/uso terapêutico , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-20953426

RESUMO

The present study investigates the anxiolytic activity of NR-ANX-C, a standardized polyherbal formulation containing the extracts of Withania somnifera, Ocimum sanctum, Camellia sinensis, Triphala, and Shilajit in ethanol withdrawal- (EW-) induced anxiety behavior in rats. Ethanol dependence in rats was produced by substitution of drinking water with 7.5% v/v alcohol for 10 days. Then, ethanol withdrawal was induced by replacing alcohol with drinking water, 12 hours prior to experimentation. After confirming induction of withdrawal symptoms in the alcohol deprived animals, the anxiolytic activity of the test compound in graded doses (10, 20, and 40 mg/kg) was compared to the standard drug alprazolam (0.08 mg/kg) in the elevated plus maze and bright and dark arena paradigms. In our study, single and repeated dose administration of NR-ANX-C reduced EW-induced anxiety in a dose-dependent manner. Even though the anxiolytic activity was not significant at lower doses, NR-ANX-C at the highest dose tested (40 mg/kg) produced significant anxiolytic activity that was comparable to the standard drug alprazolam. Based on our findings we believe that NR-ANX-C has the potential to be used as an alternative to benzodiazepines in the treatment of EW-induced anxiety.

20.
Artigo em Inglês | MEDLINE | ID: mdl-22467999

RESUMO

Insulin-stimulative and anti-oxidative effects of Persea americana fruit extract were evaluated using streptozotocin (STZ). Ethanol extract of P. americana in the concentration of 300 mg/kg body weight/rat /day was orally administered to rats introduced into STZ-induced hyperglycaemic state for a period of 30 days. After the treatment with avocado fruit extract, the elevated levels of blood glucose, glycosylated haemoglobin, blood urea and serum creatinine seen in the hyperglycaemic rats, reverted back to near normal. Similarly, significantly decreased plasma insulin and haemoglobin levels went back to near normal after the treatment, suggesting the insulin-stimulative effect of P. americana fruit. Determination of thiobarbituric acid reactive substances (TBARS), hydroperoxides and both enzymatic and non-enzymatic antioxidants, confirmed the anti-oxidative potential of avocado fruit extract which, in turn, might be responsible for its hypoglycaemic potential. Changes in activities of enzymes such as serum aspartate transaminase (AST), serum alanine transaminase (ALT), and serum alkaline phosphatase (ALP) seen in the control and experimental rats, revealed the tissue-protective nature of Persea americana fruits, while all of the analysed biochemical parameters were comparable to those obtained with gliclazide as a standard reference drug.


Assuntos
Antioxidantes/farmacologia , Linfócitos B/efeitos dos fármacos , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Persea , Extratos Vegetais/farmacologia , Administração Oral , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Glicemia/metabolismo , Creatinina/análise , Creatinina/sangue , Diabetes Mellitus Experimental/metabolismo , Relação Dose-Resposta a Droga , Etanol , Frutas , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Insulina/sangue , Peroxidação de Lipídeos , Fitoterapia , Extratos Vegetais/química , Ratos , Ratos Wistar , Estreptozocina , Substâncias Reativas com Ácido Tiobarbitúrico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...