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1.
Sci Rep ; 14(1): 17095, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39048607

RESUMO

The current analytical study is dedicated to the boundary layer regime where heat and mass transfer rates are ruled by natural convection. A rectangular enclosure filled with a combination of an arbitrary buoyancy ratio has an Oseen-linear solution, and the position of Beavers and Joseph's condition is employed at the porous fluid interface. Thermal radiation's interaction with a porous lining influences overall heat transfer in a system. Porous linings and radiation are employed in many applications, such as furnaces, insulation, heat exchangers, solar energy collecting and storage, and heat control in electronics. The effect of slip and radiation is to increase the flow rate because of the reduction in friction at the surface. It indicates the fact that temperature and concentration are rapidly lowering. As the slip parameter and radiation parameter increase, the heat and mass transport increase due to the rise in velocity. The Nusselt and Sherwood numbers reach their maximum when the radiation parameter, Rayleigh number, and slip parameter are increased. The findings of the Nusslet number and Sherwood numbers are related to the finite situations of the slip parameter tending to infinity, the radiation parameter going to zero and the angle 90°.

2.
Vet World ; 13(9): 1870-1874, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33132599

RESUMO

BACKGROUND AND AIM: Depression and anxiety are the most prominent neuropsychiatric disease and have been considered as the most burdensome diseases of society. The hippocampus and prefrontal cortex have a prominent role in stress-induced neurological disorders. Chronic unpredictable stress exposed rats are a perfect model in understanding comorbid depression and anxiety disorders. The inflammatory response occurring in the body has been linked to C-reactive protein (CRP) in many diseased conditions. The present research primarily focus on the possible correlation of Cortisol, CRP level and neuronal assay in different regions of hippocampus, dentate gyrus (DG), and prefrontal cortex. MATERIALS AND METHODS: The control group of rats (n=6) was not exposed to any stress. Whereas, the experimental stress group (n=6) of rats was exposed to various stressors for 15 days. After the experimentation procedures, the blood samples were collected and brain dissection was done. The neurons in the prefrontal cortex, the DG along with various hippocampal regions was counted. Statistical analysis was performed using student's t-test and p<0.05 was expressed as statistically significant. RESULTS: Animals exposed to chronic unpredictable stressors showed a significant (p<0.0001) decrease in the neuronal count in prefrontal cortex and hippocampus. A significant rise in the serum cortisol (p<0.0001) and CRP (p<0.001) was witnessed in the stressed group. CONCLUSION: Our results demonstrate that chronic unpredictable stress exposure has affected neurogenesis in prefrontal cortex and hippocampal regions. Decreased neurogenesis was well in coordinance with the increase in cortisol and CRP. The chronic unpredictable stress-induced inflammatory response correlated to various brain regions might provoke insights into a variety of new drugs targeting neurogenesis.

3.
Ann Allergy Asthma Immunol ; 122(4): 393-400.e2, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30639434

RESUMO

BACKGROUND: Diagnosing food allergy in patients with atopic dermatitis (AD) is complicated by their high rate of asymptomatic sensitization to foods, which can lead to misdiagnosis and unnecessary food avoidance. OBJECTIVE: We sought to determine whether food-specific (sIgE) or component immunoglobulin (Ig) E levels could predict allergic status in patients with moderate to severe AD and elevated total IgE. METHODS: Seventy-eight children (median age, 10.7 years) with moderate to severe AD were assessed for a history of clinical reactivity to milk, egg, peanut, wheat, and soy. The IgE levels for each food and its components were determined by ImmunoCAP. The level and pattern of IgE reactivity to each food and its components, and their ratio to total IgE, were compared between subjects who were allergic and tolerant to each food. RESULTS: Ninety-one percent of subjects were sensitized, and 51% reported allergic reactivity to at least 1 of the 5 most common food allergens. Allergy to milk, egg, and peanut were most common, and IgE levels to each of these foods were significantly higher in the allergic group. Component IgEs most associated with milk, egg, and peanut allergy were Bos d8, Gal d1, and Ara h2, respectively. The ratio of sIgE to total IgE offered no advantage to sIgE alone in predicting allergy. CONCLUSION: Specific IgE levels and the pattern of IgE reactivity to food components can distinguish AD subjects allergic vs tolerant to the major food allergens and may therefore be helpful in guiding the clinical management of these patients.


Assuntos
Dermatite Atópica/diagnóstico , Hipersensibilidade Alimentar/diagnóstico , Imunoglobulina E/sangue , Adolescente , Adulto , Animais , Arachis/efeitos adversos , Criança , Pré-Escolar , Dermatite Atópica/sangue , Dermatite Atópica/imunologia , Ovos/efeitos adversos , Feminino , Hipersensibilidade Alimentar/sangue , Hipersensibilidade Alimentar/imunologia , Humanos , Masculino , Leite/efeitos adversos , Índice de Gravidade de Doença , Adulto Jovem
4.
Front Immunol ; 9: 2172, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30319630

RESUMO

Antibody production and function represent an essential part of the immune response, particularly in fighting bacterial and viral infections. Multiple immunological phenotypes can result in dysregulation of the immune system humoral compartment, including class-switch recombination (CSR) defects associated with hyper-IgM (HIGM) syndromes. The CSR/HIGM syndromes are defined by the presence of normal or elevated plasma IgM levels in the context of low levels of switched IgG, IgA, and IgE isotypes. Recently described autosomal dominant gain-of-function (GOF) mutations in PIK3CD and PIK3R1 cause combined immunodeficiencies that can also present as CSR/HIGM defects. These defects, their pathophysiology and derived clinical manifestations are described in depth. Previously reported forms of CSR/HIGM syndromes are briefly reviewed and compared to the phosphoinositide 3-kinase (PI3K) pathway defects. Diseases involving the PI3K pathway represent a distinctive subset of CSR/HIGM syndromes, presenting with their own characteristic clinical and laboratory attributes as well as individual therapeutic approaches.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Síndrome de Imunodeficiência com Hiper-IgM/imunologia , Switching de Imunoglobulina/imunologia , Isotipos de Imunoglobulinas/genética , Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Classe Ia de Fosfatidilinositol 3-Quinase , Humanos , Síndrome de Imunodeficiência com Hiper-IgM/genética , Imunidade Humoral/genética , Imunidade Humoral/imunologia , Switching de Imunoglobulina/genética , Isotipos de Imunoglobulinas/imunologia , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia
5.
J Natl Med Assoc ; 110(1): 98-102, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29510852

RESUMO

PURPOSE: Obesity in females is an emerging health problem. The consumption of MSG has been considered as a risk factor for obesity. The tastemakers in Chinese and fast foods, such as fish sauce and soy sauce, contain very high levels of glutamate. The deficiency of Vitamin D is associated with obesity and metabolic syndrome. Therefore, the present study aimed to determine the effect of co-administration of Vitamin D on body weight control in MSG-induced obese rats. METHODS: Eighteen adult female Wistar rats were randomly divided into three groups equally. The first group (Group I) was treated with saline served as the control; the second group (Group II) received a daily oral dose of 5 g/kg Body weight of MSG; the third group (Group III) received the same dose of MSG along with calcitriol (0.2 mcg/kg BW) for 15 days. RESULTS: The body weight, food, and water intake were measured. MSG treated rats showed a significant increase (P < 0.001) in the body weight, food, and water intake but significant decrease (P < 0.001) was observed in the rats treated with MSG along with Vitamin D. CONCLUSION: Ingestion of Vitamin D suppresses body weight gain in MSG-induced obese rats. Active agents in Vitamin D are useful for the prevention and treatment of obesity. Foods tested with high glutamate levels can be fortified with minute quantities of calcitriol to combat the adverse effects without compromising on the taste of the food processed. The fortification of junk foods might also combat largely prevalent Vitamin D deficiency in India.


Assuntos
Obesidade , Vitamina D , Animais , Feminino , Ratos , Administração Oral , Índice de Massa Corporal , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Obesidade/induzido quimicamente , Obesidade/tratamento farmacológico , Distribuição Aleatória , Ratos Wistar , Glutamato de Sódio/toxicidade , Resultado do Tratamento , Vitamina D/administração & dosagem , Vitaminas/administração & dosagem
7.
Curr Opin Allergy Clin Immunol ; 17(6): 391-397, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29040208

RESUMO

PURPOSE OF REVIEW: Most primary immunodeficiencies described since 1952 were associated with loss-of-function defects. With the advent and popularization of unbiased next-generation sequencing diagnostic approaches followed by functional validation techniques, many gain-of-function mutations leading to immunodeficiency have also been identified. This review highlights the updates on pathophysiology mechanisms and new therapeutic approaches involving primary immunodeficiencies because of gain-of-function mutations. RECENT FINDINGS: The more recent developments related to gain-of-function primary immunodeficiencies mostly involving increased infection susceptibility but also immune dysregulation and autoimmunity, were reviewed. Updates regarding pathophysiology mechanisms, different mutation types, clinical features, laboratory markers, current and potential new treatments on patients with caspase recruitment domain family member 11, signal transducer and activator of transcription 1, signal transducer and activator of transcription 3, phosphatidylinositol-4,5-biphosphate 3-kinase catalytic 110, phosphatidylinositol-4,5-biphosphate 3-kinase regulatory subunit 1, chemokine C-X-C motif receptor 4, sterile α motif domain containing 9-like, and nuclear factor κ-B subunit 2 gain-of-function mutations are reviewed for each disease. SUMMARY: With the identification of gain-of-function mutations as a cause of immunodeficiency, new genetic pathophysiology mechanisms unveiled and new-targeted therapeutic approaches can be explored as potential rescue treatments for these diseases.


Assuntos
Autoimunidade , Síndromes de Imunodeficiência/genética , Mutação/genética , Autoimunidade/genética , Proteínas Adaptadoras de Sinalização CARD/genética , Guanilato Ciclase/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Síndromes de Imunodeficiência/imunologia , Terapia de Alvo Molecular , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais
8.
Curr Treat Options Allergy ; 3(3): 282-291, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28042528

RESUMO

Immunotherapy for peanut allergy has been an exploding topic of study within the last few years. Sublingual, epicutaneous, and oral immunotherapy are being investigated and show promise in the treatment of peanut allergy. Oral immunotherapy has shown the most clinical benefit; however, sublingual and epicutaneous immunotherapy appear to have the most favorable safety profiles. Most studies to date suggest that only a minority of subjects achieve sustained unresponsiveness to peanut after discontinuation of immunotherapy. Recent efforts have been focused on identifying adjunct therapies, such as omalizumab, that may assist patients in achieving peanut desensitization more quickly and with greater success. Several underlying immunologic mechanisms, including a switch from IgE to IgG4 production and induction of T regulatory cells, have been studied although more research is needed to identify reliable biomarkers. This article will describe the immunotherapy approaches that are being investigated to induce peanut desensitization, and highlight the benefits and risks of these therapies that need to be considered before they are ready for routine clinical practice.

9.
PLoS One ; 8(8): e72817, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24023648

RESUMO

Previously we have reported that, cycloart-23-ene-3ß, 25-diol (called as B2) and L-glutamine stimulated glucagon like peptide-1 (GLP-1) (7-36) amide secretion diabetic rats. The objective of present investigation was to investigate the concomitant administration of cycloart-23-ene-3ß, 25-diol+sitagliptin and L-glutamine+sitagliptin in streptozotocin - nicotinamide induced diabetic Sprague Dawley. Type 2 diabetes was induced in overnight fasted male Sprague Dawley rats pre-treated with nicotinamide (100 mg/kg, i.p.) followed by administration of streptozotocin (55 mg/kg, i.p.) 20 min after. The rats were divided into; I- non-diabetic, II- diabetic control, III- Sitagliptin (5 mg/kg, p.o.)+cycloart-23-ene-3ß, 25-diol (1 mg/kg, p.o.), IV- Sitagliptin (5 mg/kg, p.o.)+L-glutamine (1000 mg/kg, p.o.). The concomitant treatment of cycloart-23-ene-3ß, 25-diol and L-glutamine with sitagliptin was 8 weeks. Plasma glucose, body weight, food and water intake were determined every week. Glycosylated haemoglobin, lipid profile, plasma and colonic active (GLP-1) (7-36) amide, plasma and pancreatic insulin, histology of pancreata and biomarkers of oxidative stress were measured after 8(th) week treatment. Concomitant administration of cycloart-23-ene-3ß, 25-diol and L-glutamine with sitagliptin significantly (p<0.001) reduced plasma glucose, glyoxylated haemoglobin, lipid profile and oxidative stress parameters compared to diabetic control groups. Both concomitant treatment increased plasma and pancreatic insulin as well as plasma and colonic active (GLP-1) (7-36) amide secretion. Histological analysis by Gomori staining observed less destruction of pancreatic ß cells. The result obtained from this study; it is concluded that concomitant administration of cycloart-23-ene-3ß, 25-diol+sitagliptin and L-glutamine+sitagliptin showed additive antihyperglycaemic effect in diabetic rats.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glutamina/farmacologia , Glutamina/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Pirazinas/farmacologia , Triazóis/farmacologia , Triterpenos/farmacologia , Animais , Biomarcadores/metabolismo , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Colo/efeitos dos fármacos , Colo/metabolismo , Diabetes Mellitus Experimental/sangue , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/sangue , Glutamina/administração & dosagem , Hemoglobinas Glicadas/metabolismo , Insulina/sangue , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Niacinamida , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Pirazinas/administração & dosagem , Pirazinas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Fosfato de Sitagliptina , Coloração e Rotulagem , Estreptozocina , Triazóis/administração & dosagem , Triazóis/uso terapêutico , Triterpenos/administração & dosagem , Triterpenos/uso terapêutico
10.
Chem Biol Interact ; 203(2): 530-41, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-23466488

RESUMO

L-glutamine is a non-essential amino acid. It decreased blood sugar, stimulated insulin secretion in type 2 diabetic patients. The objective of the present investigation was to evaluate L-glutamine increases glucagon like peptide-1 (GLP-1) (7-36) amide secretion in streptozotocin-nicotinamide (STZ-NTM) induced diabetic Sprague Dawley rats. Molecular docking study was performed to elucidate the molecular basis for GLP-1 receptor agonistic activity. Type 2 diabetes was induced in overnight fasted Sprague Dawley rats pre-treated with nicotinamide (100 mg/kg, i.p.) followed by 20 min after administration of streptozotocin (55 mg/kg, i.p.). The rats were divided into; I - nondiabetic, II - diabetic control, III - sitagliptin (5 mg/kg, p.o.), IV - L-glutamine (250 mg/kg, p.o.), V - L-glutamine (500 mg/kg, p.o.) and VI - L-glutamine (1000 mg/kg, p.o.). The L-glutamine and sitagliptin treatment was 8 week. Plasma glucose was estimated every week. Body weight, food and water intake were recorded daily. Glycosylated haemoglobin, lipid profile, plasma and colonic active (GLP-1) (7-36) amide, mRNA expression of proglucagon GLP-1, plasma and pancreatic insulin, histology of pancreata and biomarkers of oxidative stress (superoxidase dismutase, reduced glutathione, malondialdehyde, glutathione peroxidase, glutathione S transferase) were measured after 8 week. In acute study, the rats were divided into I - glucose (2.5 g/kg, p.o.), II - sitagliptin (5 mg/kg, p.o.), III - L-glutamine (250 mg/kg, p.o.), IV - L-glutamine (500 mg/kg, p.o.) and V - L-glutamine (1000 mg/kg, p.o.). Plasma glucose, active GLP-1 (7-36) amide concentration and insulin levels were measured after glucose loading. The docking data indicated that l-glutamine bind to the GLP-1 receptor. L-glutamine decreased plasma glucose, increased plasma and pancreatic insulin, increased plasma and colonic active GLP-1 (7-36) amide secretion as well as decreased oxidative stress in streptozotocin-nicotinamide induced diabetic rats.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glutamina/administração & dosagem , Glutamina/farmacologia , Niacinamida/efeitos adversos , Fragmentos de Peptídeos/metabolismo , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Colo/efeitos dos fármacos , Colo/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Ingestão de Líquidos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/sangue , Peptídeo 1 Semelhante ao Glucagon/genética , Receptor do Peptídeo Semelhante ao Glucagon 1 , Teste de Tolerância a Glucose , Glutamina/metabolismo , Hemoglobinas Glicadas/metabolismo , Insulina/sangue , Insulina/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Simulação de Acoplamento Molecular , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/genética , Conformação Proteica , Pirazinas/administração & dosagem , Pirazinas/metabolismo , Pirazinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Glucagon/química , Receptores de Glucagon/metabolismo , Fosfato de Sitagliptina , Triazóis/administração & dosagem , Triazóis/metabolismo , Triazóis/farmacologia
11.
Eur J Pharmacol ; 698(1-3): 470-9, 2013 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-23117087

RESUMO

In previous study, we have reported cycloart-23-ene-3ß, 25-diol is an active antidiabetic constituent isolated from stem bark of Pongamia pinnata (Linn.) Pierre. The objective of the present investigation was to evaluate cycloart-23-ene-3ß, 25-diol stimulates glucagon like peptide-1 (GLP-1) (7-36) amide secretion in streptozotocin-nicotinamide induced diabetic Sprague Dawley rats. Molecular docking studies were performed to elucidate the molecular basis for GLP-1 receptor agonistic activity. Type 2 diabetes was induced in overnight fasted Sprague Dawley rats pre-treated with nicotinamide (100mg/kg, i.p.) followed by administration of streptozotocin (55 mg/kg, i.p.) 20 min after. The rats were divided into following groups; I- non-diabetic, II- diabetic control, III- sitagliptin (5mg/kg, p.o.), IV- cycloart-23-ene-3ß, 25-diol (1mg/kg, p.o.). The cycloart-23-ene-3ß, 25-diol and sitagliptin treatment was 8 week. Plasma glucose was estimated every week (week 0 to week 8). Body weight, food and water intake were recorded daily. Glycosylated haemoglobin, lipid profile, plasma and colonic active (GLP-1) (7-36) amide, mRNA expression of proglucagnon GLP-1, plasma and pancreatic insulin, histology of pancreata as well as biomarkers of oxidative stress (superoxidase dismutase, reduced glutathione, malondialdehyde, glutathione peroxidase, glutathione S transferase) were measured after 8th week treatment. In acute study, active GLP-1 (7-36) amide release, plasma glucose and insulin were measured during oral glucose tolerance test. The docking data clearly indicated cycloart-23-ene-3ß, 25-diol bind to the GLP-1 receptor. It decreased plasma glucose level, increased plasma and pancreatic insulin level as well as increased plasma and colonic active GLP-1 (7-36) amide secretion in streptozotocin-nicotinamide induced diabetic Sprague Dawley rats.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Niacinamida/efeitos adversos , Fragmentos de Peptídeos/metabolismo , Triterpenos/farmacologia , Animais , Biomarcadores/metabolismo , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Ingestão de Líquidos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/agonistas , Peptídeo 1 Semelhante ao Glucagon/química , Teste de Tolerância a Glucose , Insulina/sangue , Insulina/metabolismo , Masculino , Simulação de Acoplamento Molecular , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Fragmentos de Peptídeos/agonistas , Fragmentos de Peptídeos/química , Conformação Proteica , Pirazinas/administração & dosagem , Pirazinas/metabolismo , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Fosfato de Sitagliptina , Fatores de Tempo , Triazóis/administração & dosagem , Triazóis/metabolismo , Triazóis/farmacologia , Triazóis/uso terapêutico , Triterpenos/administração & dosagem , Triterpenos/metabolismo , Triterpenos/uso terapêutico
12.
Singapore Med J ; 52(10): 742-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22009395

RESUMO

INTRODUCTION: Testicular torsion is a medical emergency, especially in male neonates and adolescents. It is a common clinical outcome and a significant urological issue. From the literature, it is evident that the use of antioxidants in the prevention of testicular reperfusion injury following detorsion is conflicting. This study was conducted to investigate the role of vitamin E in testicular reperfusion injury following detorsion. METHODS: Male Wistar albino rats were divided into Groups I, II, III and IV. Only Group IV rats were pre-treated with vitamin E 100 mg/kg body weight for 30 days. Ischaemia was induced manually by rotating the rat testis to 720 degrees clockwise and counter rotating for reperfusion. The testes were fixed in Bouin's fluid and processed for histopathological examination. RESULTS: A significant decrease in the standard tubular diameter and epithelial height was observed in Group III rats compared to those in Groups I and II. However, the seminiferous tubules in Group IV rats showed recovery in the standard tubular diameter and epithelial height when compared with the untreated control groups. CONCLUSION: The results showed that vitamin E, when administered before torsion of the spermatic cord in rats, provided significant protection against acute testicular torsion and detorsion injury.


Assuntos
Traumatismo por Reperfusão/prevenção & controle , Torção do Cordão Espermático/tratamento farmacológico , Torção do Cordão Espermático/patologia , Vitamina E/farmacologia , Análise de Variância , Animais , Biópsia por Agulha , Modelos Animais de Doenças , Imuno-Histoquímica , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Valores de Referência , Testículo/efeitos dos fármacos , Testículo/patologia , Resultado do Tratamento
13.
Eur J Med Chem ; 45(6): 2237-44, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20163893

RESUMO

Two new guaiane sesquiterpene derivatives, guai-2-en-10alpha-ol (1) and guai-2-en-10alpha-methanol (2), were chromatographically purified as major constituents of the CHCl3/CH3OH (1:1, v/v) soluble fraction of Ulva fasciata. Acetylation of 2 furnished guai-2-en-10alpha-methyl methanoate (3) with acetyl group at C11 position. The structures of the compounds were elucidated using one and two-dimensional NMR and mass spectrometric analysis. Compounds 2 and 3 exhibited significant inhibition to the growth of Vibrio parahaemolyticus with minimum inhibitory concentrations of 25 and 35 microg/mL, respectively. The electronegative C10 acetyl group with high polarisability (7.02x10(-24) cm3) in 3 appeared to withdraw electron cloud from substituted cycloheptyl ring and (R)-3-methylcyclohept-1-ene moiety, thus acting as the nucleophilic center of the molecule resulting in high bioactivity.


Assuntos
Antibacterianos/farmacologia , Sesquiterpenos de Guaiano/farmacologia , Ulva/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Sesquiterpenos de Guaiano/química , Sesquiterpenos de Guaiano/isolamento & purificação , Relação Estrutura-Atividade
14.
J Hazard Mater ; 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17532133

RESUMO

This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.

15.
J Agric Food Chem ; 55(10): 4043-51, 2007 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-17407315

RESUMO

The high content of the essential fatty acids in some microalgae and baker's yeast has made them excellent diets for boosting the fatty acid content of livefood Artemia. The influences of baker's yeast (Saccharomyces cerevisiae) and three microalgae, viz., Chlorella salina, Chaetoceros calcitrans, and Nannochloropsis salina, were tested as diet components in marine livefeed brine shrimp Artemia salina nauplii to improve the polyunsaturated fatty acid (PUFA) composition. Artemia nauplii submerged in these diets for four different enrichment intervals (3, 6, 8, and 24 h) were found to incorporate essential fatty acids, and the percentage composition of different fatty acids was measured in the enriched Artemia nauplii and enrichment diets. N. salina produced higher levels of arachidonic acid (AA, 20:4n6, 9.50%), eicosapentaenoic acid (EPA, 20:5n3, 25.80%), and docosahexaenoic acid (DHA, 22:6n3, 4.18%) as compared to other diets. The total PUFA content of the enriched Artemia by N. salina increased by 56.50% with enrichment periods up to 8 h, followed by a significant reduction in the final 24 h. N. salina yielded Artemia nauplii with considerable EPA (8.05%), AA (14.15%), and DHA (1.85%) after 8 h of enrichment, which are significantly higher levels than in nauplii fed with the other three diets (p = 0.05). The DHA/EPA values in Artemia enriched for 6 h by N. salina and C. calcitrans were found to be, respectively, 88.46 and 25% higher than freshly hatched Artemia. Artemia enriched by C. salina and baker's yeast exhibited a reduction in PUFA content even at 6 h of enrichment. Significant relative decreases in DHA, EPA, and total PUFA in Artemia enriched with all of the diets were apparent, with a corresponding increase in the total saturated fatty acid content (26.95 +/- 9.75%) in the final stages (24 h) of enrichment (p = 0.05).


Assuntos
Artemia/química , Artemia/crescimento & desenvolvimento , Dieta , Eucariotos , Ácidos Graxos/análise , Saccharomyces cerevisiae , Animais , Eucariotos/química , Ácidos Graxos Insaturados/análise , Saccharomyces cerevisiae/química
16.
J Hazard Mater ; 146(1-2): 131-6, 2007 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-17208372

RESUMO

A novel column solid phase extraction procedure was developed for the determination of lead, nickel, copper and manganese in various water samples by flame atomic absorption spectrometry (FAAS) after preconcentration on sodium bispiperdine-1,1'-carbotetrathioate (Na-BPCTT) supported by Amberlite XAD-7. The sorbed element was subsequently eluted with 1M nitric acid and the acid eluates are analysed by Flame atomic absorption spectrometry (FAAS). Various parameters such as pH, amount of adsorbent, eluent type and volume, flow-rate of the sample solution, volume of the sample solution and matrix interference effect on the retention of the metal ions have been studied. The optimum pH for the sorption of above mentioned metal ions was about 6.0+/-0.2. The loading capacity of adsorbent for Pb, Cu, Ni and Mn were found to 28, 26, 22 and 20x10(-6) g/mL, respectively. The recoveries of lead, copper, nickel and manganese under optimum conditions were found to be 96.7-99.2 at the 95% confident level. The limit of detection was 3.0, 3.2, 2.8 and 3.6x10(-6) g/mL for lead, copper, nickel and manganese, respectively by applying a preconcentration factor 50. The proposed enrichment method was applied for metal ions in various water samples. The results were obtained are good agreement with reported method.


Assuntos
Metais Pesados/análise , Poluentes Químicos da Água/análise , Resinas Acrílicas/química , Adsorção , Concentração de Íons de Hidrogênio , Metais Pesados/química , Piperidinas/química , Poliestirenos/química , Extração em Fase Sólida , Espectrofotometria Atômica , Poluentes Químicos da Água/química
17.
J Hazard Mater ; 146(1-2): 137-41, 2007 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-17222507

RESUMO

4-amino methyl pyridine anchored silica gel (4-AMPS) was used as a sorbent in a simple sensitive spectrophotometry determination of Co(II) in various samples using piperazine dithiocarbamate as a color developing agent (lambda(max)=390 nm) at pH 5.0+/-0.2. Beer's law was obeyed over the range of 0.1-5.0 microg ml(-1). The molar absorptivity and Sandell's sensitivity were 1.257x10(5) lmol(-1) cm(-1) and 0.006145 microg cm(-2), respectively. Under these conditions, the preconcentration factor obtained was 80, and the detection limit achieved was 5.0 ng ml(-1). The detailed study of various interfering ions made the method more sensitive and selective. The recovery of Co(II) from various samples range from 97.50 to 99.66%. The present method was successfully applied for the determination of Co(II) in various water and soil samples. The proposed method was compared with reported methods in terms of Student's 't'-test and variance ratio 'f'-test which indicates that there is no significant difference between proposed and literature method at 95% confidence level.


Assuntos
Cobalto/análise , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Adsorção , Carbamatos/química , Cobalto/química , Concentração de Íons de Hidrogênio , Piperidinas/química , Sílica Gel , Dióxido de Silício/química , Poluentes do Solo/química , Espectrofotometria , Poluentes Químicos da Água/química
18.
Talanta ; 71(2): 588-95, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19071345

RESUMO

This article has been retracted at the request of the Editors-in-Chief. Please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Reason: Considerable concern was raised about the research purportedly conducted at Sri Venkateswara University, India with the alleged involvement of Professor P. Chiranjeevi. Questions were raised as to the volume of publications, the actual capacity (equipment, orientation and chemicals) of the laboratory in which Professor Chiranjeevi worked, the validity of certain of the research data identified in the articles, the fact that a number of papers appear to have been plagiarized from other previously published papers, and some aspects of authorship. Professor Chiranjeevi was given the opportunity to respond to these allegations. Thereafter, a committee was constituted by the University to look into these allegations. Based on the enquiry committee report, we have been informed by the head of the Department of Chemistry at Sri Venkateswara University that the university authorities have taken disciplinary action against ProfessorChiranjeevi, as the university considers that there are grounds for such action. Therefore, based on the results of this investigation, the Editors-in-Chief are retracting this article.

19.
J Hazard Mater ; 140(1-2): 180-6, 2007 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-16872742

RESUMO

A Novel, rapid, sensitive and selective reactions are developed for spectrophotometric determination of trace amounts of vanadium (V) in environmental, biological, pharmaceutical and alloy samples was studied. The methods were based on interactions of 4-bromophenyl hydrazine (4-BPH) with N-(1-naphthyl ethylenediamine dihydrochloride (NEDA) in the presence of vanadium in acidic medium (acetate buffer of pH 3.0) to give violet colored derivative or on the oxidation of 4-bromophenyl hydrazine by vanadium in basic medium and coupling with chromotropic acid (CA) to yield red color derivative. The violet color derivative having an absorbance maximum at 570nm which is stable for 7 days and the red derivative with lambda(max) 495nm for 5 days. Beer's law was obeyed for vanadium in the concentration range of 0.5-6.0microgml(-1) (violet derivative) and 0.6-7.0microgml(-1) (red derivative), respectively. The optimum reaction conditions and other important analytical parameters were established to enhance the sensitivity of the proposed methods. Interference due to various non-target ions was also investigated. The proposed methods were applied to the analysis of vanadium (V) in environmental, biological, pharmaceutical and steel samples. The performance of proposed methods were evaluated in terms of Student's t-test and Variance ratio F-test that indicates the significance of proposed methods over reported method.


Assuntos
Vanádio/análise , Cor , Poluentes Ambientais/análise , Oxirredução , Preparações Farmacêuticas/análise , Análise Espectral , Aço/análise
20.
Environ Monit Assess ; 127(1-3): 67-72, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16897507

RESUMO

Facile, selective and sensitive spectrophotometric method has been developed for the determination of bendiocarb in its insecticidal formulations, fortified water, food grains, agriculture wastewater and agriculture soil samples with prepared reagents. The method was based on alkaline hydrolysis of the bendiocarb pesticide, and the resultant hydrolysis product of bendiocarb was coupled with 2,6-dibromo-4-methylaniline to give a yellow color product with lambda max of 457 nm or coupling with 2, 6-dibromo-4-nitroaniline to produce a red colored product with lambda max of 474 nm or coupling with 2, 4, 6-tribromoaniline to form orange red colored product has a lambda max of 465 nm. Under optimal conditions, Beer's law range for 2, 6-dibromo-4-methylaniline (DBMA) was found to be 0.6-14.0 microg mL (-1), 0.8-10.0 microg mL (-1) for 2, 6-dibromo-4-nitroaniline (DBNA) and 0.4-10.0 microg mL (-1) for 2, 4, 6-tribromoaniline (TBA). The molar absorptivity of the color systems were found to be 4.126 x 10(4) l mol (-1) cm (-1) for DBMA, 3.254 x 10(4) l mol (-1) cm (-1) for DBNA and 2.812 x 10(4) l mol (-1) cm (-1) for TBA. Sandell's of the color reactions are 0.018 microg cm (-2)(DBMA), 0.052 microg cm (-2)(DBNA) and 0.065 microg cm (-2) (TBA) respectively. The effect of the non-target species on the determination of bendiocarb was studied. The formation of colored derivatives with the coupling agents is instantaneous and stable for 18 h, 30 h, and 12 h. Performance of the proposed methods were compared statistically in terms Student's F and t-tests with the reported methods.


Assuntos
Monitoramento Ambiental , Fenilcarbamatos/química , Espectrofotometria/métodos , Índia , Fenilcarbamatos/análise
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