Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Biomed Pharmacother ; 112: 108571, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30798130

RESUMO

Sildenafil Citrate (SC) is a US FDA approved drug, have been used to treat wounds due to their nitric oxide (NO) stimulating activity in the tissue. But, there are only a few studies about the topical effect of this drug on the healing of traumatic wounds. The purpose of the study is to develop topical SC hydrogel (SCH) and to investigate its dermal toxicity and wound healing efficacy in Sprague dawley rats. In the present study, hydrogel containing SC showed no change and stable with respect to pH, homogeneity, spreadability and effiecient encapsulation. SEM analysis represents the uniform texture of the SCH. Acute dermal toxicity of the SCH exhibited that the formulations are devoid of any toxic effects and safe to be used. Percentage of wound contraction, re-epithelization, tensile strength and biochemical parameters such as hydroxyproline, collagen, total protein and NO content at dermal level prove the wound healing efficacy of prepared SCH. In addition, histopathology confirmed that the SCH promoted re-epithelization, collagen synthesis, deposition and regeneration of skin appendages. Results demonstrated that SCH has no dermal toxicity and promoted wound healing. Thus, prepared SCH shows promising skin wound healing property against traumatic wounds.


Assuntos
Hidrogéis/administração & dosagem , Citrato de Sildenafila/administração & dosagem , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Administração Tópica , Animais , Composição de Medicamentos , Feminino , Hidrogéis/química , Hidrogéis/toxicidade , Ratos , Ratos Sprague-Dawley , Citrato de Sildenafila/química , Citrato de Sildenafila/toxicidade , Pele/metabolismo , Pele/patologia , Resultado do Tratamento , Vasodilatadores/administração & dosagem , Vasodilatadores/química , Vasodilatadores/toxicidade , Cicatrização/fisiologia
2.
Disaster Med Public Health Prep ; 13(2): 197-202, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29792236

RESUMO

OBJECTIVE: Researchers have been evaluating several approaches to assess acute radiation injury/toxicity markers owing to radiation exposure. Keeping in mind this background, we assumed that whole-body irradiation in single fraction in graded doses can affect the antioxidant profile in skin that could be used as an acute radiation injury/toxicity marker. METHODS: Sprague-Dawley rats were treated with CO-60 gamma radiation (dose: 1-5 Gy; dose rate: 0.85 Gy/minute). Skin samples were collected (before and after radiation up to 72 hours) and analyzed for glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), and lipid peroxidation (LPx). RESULTS: Intra-group comparison showed significant differences in GSH, GPx, SOD, and CAT, and they declined in a dose-dependent manner from 1 to 5 Gy (P value0.05). CONCLUSIONS: This study suggests that skin antioxidants were sensitive toward radiation even at a low radiation dose, which can be used as a predictor of radiation injury and altered in a dose-dependent manner. These biochemical parameters may have wider application in the evaluation of radiation-induced skin injury and dose assessment. (Disaster Med Public Health Preparedness. 2019;13:197-202).


Assuntos
Fenômenos Bioquímicos/efeitos da radiação , Relação Dose-Resposta à Radiação , Raios gama/classificação , Pele/efeitos da radiação , Animais , Modelos Animais de Doenças , Estresse Oxidativo/efeitos da radiação , Ratos Sprague-Dawley/classificação
3.
Drug Dev Ind Pharm ; 43(11): 1759-1769, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28581835

RESUMO

Calcium chloride is an essential calcium channel agonist which plays an important role in the contraction of muscles by triggering calcium channel. First time hypothesized about its role in the treatment of GER (gastro-esophageal reflux) and vomiting disorder due to its local action. There are two objectives covered in this study as first, the development and optimization of floating formulation of calcium chloride and another objective was to evaluate optimized formulation through gamma scintigraphy in human subjects. Gastro retentive formulation of calcium chloride was prepared by direct compression method. Thirteen tablet formulations were designed with the help of sodium chloride, HPMC-K4M, and carbopol-934 along with effervescing agent sodium bicarbonate and citric acid. Formulation (F8) fitted best for Korsmeyer-Peppas equation with an R2 value of 0.993. The optimized formulation was radiolabelled with 99mTc-99 m pertechnetate for its evaluation by gamma scintigraphy. Gastric retention (6 h) was evaluated by gamma scintigraphy in healthy human subjects and efficacy of present formulation confirmed in GER positive human subjects. Gamma scintigraphy results indicated its usefulness in order to manage GERD. Stability studies of the developed formulation were carried out as per ICH guidelines for region IV and found out to be stable for 24 months.


Assuntos
Acrilatos/química , Canais de Cálcio/metabolismo , Refluxo Gastroesofágico/metabolismo , Cintilografia , Compostos Radiofarmacêuticos/química , Bicarbonato de Sódio/química , Comprimidos/administração & dosagem , Tecnécio/química , Administração Oral , Disponibilidade Biológica , Canais de Cálcio/química , Química Farmacêutica , Humanos , Compostos Radiofarmacêuticos/metabolismo , Bicarbonato de Sódio/metabolismo , Comprimidos/química
4.
Luminescence ; 32(7): 1252-1262, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28512990

RESUMO

Chalcones possess various biological properties, for example, antimicrobial, anti-inflammatory, analgesic, antimalarial, anticancer, antiprotozoal and antitubercular activity. In this study, naphthylchalcone derivatives were synthesized and characterized using 1 H NMR 13 C NMR, Fourier transform infrared and mass techniques. Yields for all derivatives were found to be >90%. Protein-drug interactions influence the absorption, distribution, metabolism and excretion (ADME) properties of a drug. Therefore, to establish whether the synthesized naphthylchalcone derivatives can be used as drugs, their binding interaction toward a serum protein (bovine serum albumin) was investigated using fluorescence, circular dichroism and molecular docking techniques under physiological conditions. Fluorescence quenching of the protein in the presence of naphthylchalcone derivatives, and other derived parameters such as association constants, number of binding sites and static quenching involving confirmed non-covalent binding interactions in the protein-ligand complex were observed. Circular dichroism clearly showed changes in the secondary structure of the protein in the presence of naphthylchalcones, indicating binding between the derivatives and the serum protein. Molecular modelling further confirmed the binding mode of naphthylchalcone derivatives in bovine serum albumin. A site-specific molecular docking study of naphthylchalcone derivatives with serum albumin showed that binding took place primarily in the aromatic low helix and then in subdomain II. The dominance of hydrophobic, hydrophilic and hydrogen bonding was clearly visible and was responsible for stabilization of the complex.


Assuntos
Chalconas/química , Chalconas/metabolismo , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Sítios de Ligação , Chalconas/farmacocinética , Dicroísmo Circular , Simulação por Computador , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Simulação de Acoplamento Molecular , Naftóis/química , Estrutura Secundária de Proteína , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Biomed Pharmacother ; 87: 92-101, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28049097

RESUMO

BACKGROUND: Rheumatoid arthritis (RA), an autoimmune inflammatory disorder with synovial hyperplasia, destruction of cartilage, bone damage is often associated with risk of infections. Such risk could be attributed towards usage of immunosuppressive agents. Thus, the present study was undertaken to evaluate the anti-arthritic efficacy of aquo-alcoholic extract of Camellia sinensis (L.). MATERIAL AND METHODS: Dried leaves of Camellia sinensis (L.) or Cs were filtered and extracted in 1:1 aqueous: ethanol by Soxhlet apparatus followed by lyophilization and spray drying to develop amorphous powder. Four different oral doses (50, 100, 200, 400mg/kg/body wt.) of aquo-alcoholic extract were evaluated for anti-edematogenic effect in collagen induced arthritis model. The selected anti-arthritic doses of Cs were evaluated for the oxidative stress markers like Glutathione [5-5'dithio-bis-2-nitrobenzoicacid (DTNB)], Superoxide dismutase [Epinephrine], Catalase [Hydrogen peroxide], Lipid peroxidation [Thiobarbituric acid reactive substance (TBARS)], Nitric oxide [Griess reagents:Nitrobluetetrazolium], Articular elastase [N-methoxysuccinyl-Ala-Ala-Pro- Val p-nitroanilide] in joints followed by haematological evaluation including RBC, WBC, Haemoglobin, platelets and haematocrit. To validate these biochemical changes, the radiological and histopathological (Haematoxylin & Eosin) evaluation was also conducted. RESULTS: The selected anti-arthritic dose of Cs i.e. 400mg/kg/body wt. (∼60% anti-arthritic efficacy on 35th day) could be attributed towards significant (p<0.05) increase in the levels of enzymatic (Superoxide dismutase and Catalase) and non-enzymatic (Glutathione) antioxidants by 34%, 59% and 50% respectively. Simultaneously, the significant (p<0.05) reduction of lipid peroxides, nitrite radical and elastase activity by 32%, 45% & 32% respectively as compare to control indicated overall decrease in oxidative stress. Haematological evaluation revealed restoration of RBC, WBC and platelets level in treatment group. The confirmatory analysis utilizing radiological and histological assessment showed alleviation of joint deformity, tissue swelling, pannus formation and neutrophils infiltration in treatment group as compared to collagen induced arthritis. CONCLUSION: The analysis showed that Cs can play an effective role in reduction of oxidative stress by modulating levels of antioxidants, reducing levels of free radicals while restoring normal haematopoietic cascade as observed in collagen induced arthritis model. Thus, the cumulative dose impact of 400mg/kg body wt., over a period of 14days also found extremely effective in terms of safeguarding their structural conformity against such auto-immune disorder.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Camellia sinensis , Extratos Vegetais/uso terapêutico , Animais , Antirreumáticos/isolamento & purificação , Feminino , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Ratos , Ratos Wistar , Resultado do Tratamento
6.
Microb Pathog ; 101: 76-82, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27836761

RESUMO

Increasing occurrence of gastroenteritis outbreaks caused by food borne opportunistic microorganisms has become a major problem in food industry as well as in immunocompromised host. Antimicrobial agents are losing their efficacy due to increase in the microbial resistance. For such reasons, conventional treatment has become limited to manage the infections state. Need of the hour is to instigate the search for safer holistic alternatives. The present study was hence conducted to assess the antibiofilm effect and mode of action of aquo alcoholic extracts of Holarrhena antidysentrica (Ha) and Andrographis paniculata (Ap) against the Salmonella enterica serovar typhimurium. Both the extracts were screened for the presence of phytocompounds followed by the characterization using Attenuated Total Reflection (ATR) infrared spectroscopy and bioactivity finger print analysis. Anti-biofilm assays were determined to test the potential of both extracts to inhibit the biofilm formation, while Propidium Iodide (PI) uptake analysis revealed that cell membrane was damaged by the exposure of nutraceuticals for 1 h. This study has demonstrated that both nutraceuticals have anti-biofilm and antimicrobial activity perturbing the membrane integrity of food-borne S. typhimurium and could be used as curative remedy to control the food borne microbial infection.


Assuntos
Andrographis/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Holarrhena/química , Extratos Vegetais/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Membrana Celular/fisiologia , Permeabilidade/efeitos dos fármacos , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/isolamento & purificação , Propídio/análise , Salmonella typhimurium/fisiologia , Análise Espectral , Coloração e Rotulagem
7.
Ukr Biochem J ; 88(1): 22-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29227075

RESUMO

The effect of whole body gamma irradiation (WBI) in single fraction was studied, as well as its influence on the secretion of various biochemical markers and cellular component that could be used as acute radiation lung injury marker. Sprague dawley rats were treated with WBI (60Co) of radiation dose from 1 Gy to 5 Gy (dose rate - 0.95 Gy/min). Bronchoalveolar lavage fluid was retrieved from all animals in control and radiation treated groups up to 72 h post radiation. Bronchoalveolar lavage fluid (BALF) was analyzed for lactate dehydrogenase (LDH ), acid phosphatase (AP ), alkaline phosphatase (ALP ), cell count and total protein. Intragroup and intergroup comparison of BALF parameters at different radiation doses showed significant difference. LDH was significantly increased as the dose increased from 1Gy to 5Gy (P = 0.00) after 2 h with effect size of difference (r > 0.3). ALP was significantly altered after 3Gy and 4Gy (P < 0.05). AP was significantly altered at 2Gy-5Gy (p < 0.05). Total protein level changed significantly from 1Gy to 5Gy (P < 0.00). Cellular content of BALF showed significant changes after radiation exposure. BALF parameters like LDH, AP, ALP, neutrophils, lymphocytes, total leukocyte count and total protein were sensitive to radiation exposure and their levels vary significantly up to 72 h after single whole body radiation exposure in Sprague dawley rats. It can be concluded that the biochemical indices in BALF have more wide application in evaluation of acute radiation induced lung injury.


Assuntos
Raios gama/efeitos adversos , Lesão Pulmonar/patologia , Lesões Experimentais por Radiação/patologia , Fosfatase Ácida/imunologia , Fosfatase Ácida/metabolismo , Fosfatase Alcalina/imunologia , Fosfatase Alcalina/metabolismo , Animais , Biomarcadores/análise , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Relação Dose-Resposta à Radiação , L-Lactato Desidrogenase/imunologia , L-Lactato Desidrogenase/metabolismo , Contagem de Leucócitos , Lesão Pulmonar/enzimologia , Lesão Pulmonar/imunologia , Linfócitos/imunologia , Linfócitos/patologia , Masculino , Neutrófilos/imunologia , Neutrófilos/patologia , Lesões Experimentais por Radiação/enzimologia , Lesões Experimentais por Radiação/imunologia , Ratos , Ratos Sprague-Dawley , Irradiação Corporal Total
9.
Ann Indian Acad Neurol ; 17(3): 308-12, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25221401

RESUMO

OBJECTIVES: Changes in lifestyle habits such as diet modification or supplementation have been indicated as probable protective factors for a number of chronic conditions including Alzheimer's disease (AD). With this background, we aim to hypothesize that whether C677T polymorphism of methylenetetrahydrofolate reductase (MTHFR) gene contributes towards the risk of developing AD and its association with vitamin B12 and folate levels. MATERIALS AND METHODS: A case-control study comprising of total 200 subjects, within the age group of 50-85 years. Their blood samples were analyzed for serum folate, vitamin B12 levels, and MTHFR C677T polymorphism by restriction fragment length polymorphism (RFLP). RESULTS: The mean plasma levels of vitamin B12 and folate were significantly lower in study group when compared to the control group (P < 0.001). Genotypic and allelic frequency of MTHFR gene in both groups was found to be significant (P < 0.05). The intergenotypic variations of vitamin B12 and folate were found to be significant (P < 0.001). CONCLUSION: We concluded that the subjects with homozygous mutated alleles are more prone to AD and also pointed out the influence of presence/absence of MTHFR T allelic variants on serum folate and vitamin B12 levels.

10.
J Geriatr Psychiatry Neurol ; 27(2): 119-27, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24584466

RESUMO

OBJECTIVES: It has been assumed that the association between Alzheimer disease (AD) and pesticides may be stronger among genetically susceptible individuals. The aim of the study was to examine the genetic polymorphism in cytochrome P450 2D6 (CYP2D6) and glutathione S-transferases pi 1 (GSTP1) with respect to organochlorine pesticides (OCPs) and metals in AD. METHODS: This study included 100 patients with AD and 100 age-matched controls. The genetic polymorphisms were analyzed by restriction fragment length polymorphism. The OCPs and serum metal levels were determined using gas chromatography and an autoanalyzer, respectively. RESULTS: We found a statistically significant association between AD and high levels of ß-hexachlorocyclohexane (ß-HCH; odds ratio [OR] = 2.064, 95% confidence intervals [95% CIs] = 1.373-3.102, dieldrin [OR = 2.086, 95% CI = 1.224-3.555], and copper [OR = 1.038, 95% CI = 1.012-1.064). The significant low level of magnesium (OR = 0.151, 95% CI = 0.047-0.489) even appears to have a protective role against AD. The GSTP1*B (P = .009) and GSTP1*C (P = .011) allelic variants were associated with increase in AD risk. CONCLUSION: This study demonstrates that the GSTP1*B and *C allelic variants may be considered a candidate gene for AD. It can be suggested that although CYP2D6*4 polymorphism is not a risk of AD, the CYP2D6*4 and GSTP1 polymorphism may interact with ß-HCH, dieldrin, and copper to influence the risk of AD.


Assuntos
Doença de Alzheimer/genética , Povo Asiático/genética , Citocromo P-450 CYP2D6/genética , Glutationa S-Transferase pi/genética , Hidrocarbonetos Clorados/sangue , Praguicidas/sangue , Idoso , Alelos , Doença de Alzheimer/etnologia , Estudos de Casos e Controles , Cromatografia Gasosa , Cobre/sangue , Dieldrin/sangue , Feminino , Predisposição Genética para Doença , Genótipo , Hexaclorocicloexano/sangue , Humanos , Magnésio/sangue , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição
11.
Biomech Model Mechanobiol ; 4(2-3): 132-46, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16365733

RESUMO

Mechanical loading-induced signals are hypothesized to be transmitted and integrated by connected bone cells before reaching the bone surfaces where adaptation occurs. A computational connected cellular network (CCCN) model is developed to explore how bone cells perceive and transmit the signals through intercellular communication. This is part two of a two-part study in which a CCCN is developed to study the intercellular communication within a grid of bone cells. The excitation signal was computed as the loading-induced bone fluid shear stress in part one. Experimentally determined bone adaptation responses (Gross et al. in J Bone Miner Res 12:982-988, 1997 and Judex et al. in J Bone Miner Res 12:1737-1745, 1997) are correlated with the fluid shear stress by the CCCN, which adjusts cell sensitivities (loading and signal thresholds) and connection weights. Intercellular communication patterns extracted by the CCCN indicate the cell population responsible for perceiving the loading-induced signal, and loading threshold is shown to play an important role in regulating the bone response.


Assuntos
Aves/fisiologia , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Comunicação Celular , Modelos Biológicos , Algoritmos , Animais , Desenvolvimento Ósseo , Simulação por Computador , Resistência ao Cisalhamento , Estresse Mecânico , Suporte de Carga
12.
Biomech Model Mechanobiol ; 4(2-3): 118-31, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16254728

RESUMO

Mechanical loading-induced signals are hypothesized to be transmitted and integrated by a bone-connected cellular network (CCN) before reaching the bone surfaces where adaptation occurs. Our objective is to establish a computational model to explore how bone cells transmit the signals through intercellular communication. In this first part of the study the bone fluid shear stress acting on every bone cell in a CCN is acquired as the excitation signal for the computational model. Bending and axial loading-induced fluid shear stress is computed in transverse sections of avian long bones for two adaptation experiments (Gross et al. in J Bone Miner Res 12:982-988, 1997 and Judex et al. in J Bone Miner Res 12:1737-1745, 1997). The computed fluid shear stress is found to be correlated with the radial strain gradient but not with bone formation. These results suggest that the radial strain gradient is the driving force for bone fluid flow in the radially distributed lacunar-canalicular system and that bone formation is not linearly related to the loading-induced local stimulus.


Assuntos
Aves/fisiologia , Osso e Ossos/fisiologia , Animais , Desenvolvimento Ósseo , Simulação por Computador , Modelos Biológicos , Rádio (Anatomia)/citologia , Resistência ao Cisalhamento , Estresse Mecânico , Tarso Animal/fisiologia , Suporte de Carga
14.
Neural Netw ; 11(6): 1027-1039, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12662772

RESUMO

In this paper we discover and explore a useful property of the fractional correction rule, a variation of the perceptron learning rule, for a single neural unit. We rename this rule the projection learning rule (PrLR), which seems more appropriate because of the technique that we use to prove convergence. We state and prove a more powerful convergence theorem and establish the link with S. Agmon's work (1954) on linear inequalities. The hallmark of this rule is that if the problem is not linearly separable then the proposed rule will always converge to the origin of the weight-space. This points out that appropriate nonlinear methods (e.g., multilayer neural network, nonlinear transformation on input-space etc.) should be used to address this problem. On the other hand, if the patterns are linearly separable, the performance of this rule is equivalent to that of the perceptron rule. A theoretical investigation of this rule leads to interesting observations. We present experimental results with linearly separable as well as linearly non-separable data using the PrLR and compare its performance with that of the perceptron rule.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...