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1.
Indian J Med Microbiol ; 33(4): 572-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26470967

RESUMO

BACKGROUND: The Revised National Tuberculosis Control Programme (RNTCP) is implementing the External Quality assurance (EQA) and Random blinded re-checking (RBRC) as one of its important component. This nationwide study was conducted to determine (1) the number and types of RBRC errors and (2) the sensitivity and specificity among rechecked slides. MATERIALS AND METHODS: The study was based on the monthly RBRC reports submitted by ~13,000 designated microscopy centres (DMCs) across the country under routine programmatic settings in 2010. The DMCs reports were compiled at district, state and national level. RESULTS: A total of 11, 89,564 slides were rechecked from 11,039 DMCs. Of which 99.5% of rechecked slides did not have any errors. The sensitivity and specificity of the rechecked slides had 98% sensitivity and 100% specificity. CONCLUSION: RBRC is the crucial component of EQA and the results from the programme are found to be satisfactory. Based on the study findings, the earlier value of 80% sensitivity used for calculation of annual sample size for RBRC has been increased to 90% sensitivity. The annual RBRC sample size for DMCs has been increased by 1.5-2 folds.


Assuntos
Testes Diagnósticos de Rotina/métodos , Microscopia/métodos , Tuberculose/diagnóstico , Erros de Diagnóstico , Humanos , Índia , Controle de Qualidade , Estudos Retrospectivos , Sensibilidade e Especificidade
2.
Oncogenesis ; 2: e38, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25522435

RESUMO

Choline kinase alpha (ChoKα) is regarded as an attractive cancer target. The enzyme catalyses the formation of phosphocholine(PCho), an important precursor in the generation of phospholipids essential for cell growth. ChoKα has oncogenic properties and is critical for the survival of cancer cells. Overexpression of the ChoKα protein can transform noncancer cells into cells with a cancerous phenotype, and depletion of the ChoKα protein can result in cancer cell death. However, the mechanisms underlying the tumourigenic properties of ChoKα are not fully understood. ChoKα was recently demonstrated to associate with other oncogenic proteins, raising the possibility that a non-catalytic protein scaffolding function drives the tumourigenic properties of ChoKα rather than a catalytic function. In order to differentiate these two roles, we compared the impact on cancer cell survival using two tools specific for ChoKα: (1) small interfering RNA (siRNA) to knockdown the ChoKα protein levels; and (2) compound V-11-0711, a novel potent and selective ChoKα inhibitor (ChoKα IC50 20 nM), to impede the catalytic activity. Both treatments targeted the endogenous ChoKα protein in HeLa cells, as demonstrated by a substantial reduction in the PCho levels. siRNA knockdown of the ChoKα protein in HeLa cells resulted in significant cell death through apoptosis. In contrast, compound V-11-0711 caused a reversible growth arrest. This suggests that inhibition of ChoKα catalytic activity alone is not sufficient to kill cancer cells, and leads us to conclude that there is a role for the ChoKα protein in promoting cancer cell survival that is independent of its catalytic activity.


Assuntos
Sobrevivência Celular/fisiologia , Colina Quinase/fisiologia , Fosforilcolina/metabolismo , Colina Quinase/antagonistas & inibidores , Células HeLa , Humanos , Neoplasias/fisiopatologia , RNA Interferente Pequeno
3.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 4925-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17947122

RESUMO

A previous design of a biofeedback system for Neurorehabilitation in an interactive multimodal environment has demonstrated the potential of engaging stroke patients in task-oriented neuromotor rehabilitation. This report explores the new concept and alternative designs of multimedia based biofeedback systems. In this system, the new interactive multimodal environment was constructed with abstract presentation of movement parameters. Scenery images or pictures and their clarity and orientation are used to reflect the arm movement and relative position to the target instead of the animated arm. The multiple biofeedback parameters were classified into different hierarchical levels w.r.t. importance of each movement parameter to performance. A new quantified measurement for these parameters were developed to assess the patient's performance both real-time and offline. These parameters were represented by combined visual and auditory presentations with various distinct music instruments. Overall, the objective of newly designed system is to explore what information and how to feedback information in interactive virtual environment could enhance the sensorimotor integration that may facilitate the efficient design and application of virtual environment based therapeutic intervention.


Assuntos
Biorretroalimentação Psicológica , Doenças do Sistema Nervoso/reabilitação , Algoritmos , Braço , Simulação por Computador , Computadores , Desenho de Equipamento , Humanos , Movimento , Música , Desempenho Psicomotor , Software , Som , Interface Usuário-Computador , Visão Ocular
4.
Neuroscience ; 126(2): 381-90, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15207356

RESUMO

In this study we have employed the selective glycine transporter-1 (GlyT-1) and GlyT-2 transporter inhibitors R-(-)-N-methyl-N-[3-[(4-trifluoromethyl)phenoxy]-3-phenyl-propyl]glycine (1:1) lithium salt (Org 24598) and 4-benzyloxy-3,5-dimethoxy-N-[1-(dimethylaminocyclopently)methyl]benzamide (Org 25543), respectively, and microdialysis perfusion to determine the effect of GlyT transporter inhibition on extracellular amino acid concentrations in the lumbar dorsal spinal cord of the halothane-anaesthetised rat. Reverse dialysis of Org 24598 (0.1-10 microM) induced a concentration-related increase in extracellular glycine accompanied by a progressive increase in citrulline, but not aspartate, glutamate or GABA, efflux. Org 25543 (10 microM) by the same route induced a similar increase in glycine levels without affecting the efflux of other amino acids quantified. To test the hypothesis that the increase in citrulline efflux resulted from activation of the N-methyl-D-aspartate receptor (NMDA-R)/nitric oxide synthase (NOS) signalling cascade, the sensitivity was determined of GlyT-1 inhibition-induced effects to NMDA-R antagonism or NOS inhibition. Co-administration by reverse dialysis of the selective NMDA-R channel blocker MK-801 (0.5 mM) or the selective antagonist of the strychnine-insensitive glycine site, 7-chlorokynurenic acid (1 mM), with Org 24598 (10 microM) did not affect the uptake inhibition-induced increase in glycine efflux, but did significantly attenuate the increase in extracellular citrulline. Similarly, co-administration with Org 24598 of the isoform non-selective and selective neuronal NOS inhibitors Nomega-nitro-L-arginine methyl ester (1 mM) or 1-(2-trifluoromethylphenyl)imidazole (0.2 mM), respectively, prevented Org 24598-induced citrulline efflux with no effect on increased glycine efflux. These data provide evidence that the observed increased in extracellular citrulline is a consequence of positive modulation of NMDA-R, secondary to increased extracellular glycine and support a protective role for GlyT-1 against fluctuations in extracellular glycine uptake at glutamatergic synapses in the dorsal spinal cord. Such a mechanism could be important to NMDA-R-mediated synaptic plasticity in the spinal cord and be of relevance to the clinical usage of GlyT-1 inhibitors.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros/antagonistas & inibidores , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Glicina/análogos & derivados , Células do Corno Posterior/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Glicina/farmacologia , Proteínas da Membrana Plasmática de Transporte de Glicina , Masculino , Células do Corno Posterior/efeitos dos fármacos , Ratos , Ratos Wistar
5.
J Med Chem ; 44(22): 3582-91, 2001 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-11606122

RESUMO

In the search for a novel water-soluble general anesthetic agent the activity of an alpha-amino acid phenolic ester lead, identified from patent literature, was markedly improved. In addition to improving in vivo activity in mice, good in vitro activity at GABA(A) receptors was also conferred. Within the series of compounds good enantioselectivity for both in vitro and in vivo activity was found, supporting a protein-mediated mechanism of action for anesthesia involving allosteric modulation of GABA(A) receptors. alpha-Amino acid phenolic ester 19, as the hydrobromide salt Org 25435, was selected for clinical evaluation since it retained the best overall anesthetic profile coupled with improved stability and water solubility. In the clinic it proved to be an effective intravenous anesthetic in man with rapid onset of and recovery from anesthesia at doses of 3 and 4 mg/kg.


Assuntos
Aminoácidos/síntese química , Anestésicos Gerais/síntese química , GABAérgicos/síntese química , Fenóis/síntese química , Receptores de GABA-A/efeitos dos fármacos , Regulação Alostérica , Aminoácidos/química , Aminoácidos/farmacologia , Anestésicos Gerais/química , Anestésicos Gerais/farmacologia , Animais , Encéfalo/metabolismo , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos , Ésteres , GABAérgicos/química , GABAérgicos/farmacologia , Técnicas In Vitro , Masculino , Camundongos , Modelos Moleculares , Oócitos/fisiologia , Fenóis/química , Fenóis/farmacologia , Ensaio Radioligante , Ratos , Ratos Wistar , Solubilidade , Relação Estrutura-Atividade , Xenopus laevis
7.
Bioorg Med Chem Lett ; 11(7): 927-30, 2001 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-11294393

RESUMO

Propofol (2,6-diisopropylphenol) is a widely used intravenous anaesthetic that is formulated as an emulsion since it lacks water solubility. We report a range of water-soluble analogues of propofol, containing a para-alkylamino substituent, which retain good intravenous anaesthetic activity in rodents.


Assuntos
Anestésicos Intravenosos/síntese química , Anestésicos Intravenosos/farmacologia , Compostos de Anilina/química , Propofol/análogos & derivados , Propofol/farmacologia , Receptores de GABA-A/efeitos dos fármacos , Anestésicos Intravenosos/química , Animais , Eletroencefalografia/efeitos dos fármacos , Concentração Inibidora 50 , Masculino , Camundongos , Propofol/química , Ratos , Ratos Wistar , Solubilidade , Relação Estrutura-Atividade
8.
J Med Chem ; 43(22): 4118-25, 2000 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11063608

RESUMO

Various cyclic ether and other 3 alpha-hydroxyandrostane derivatives bearing a conformationally constrained hydrogen-bonding moiety were prepared. Their anesthetic potency and their binding affinity for GABA(A) receptors, measured by intravenous administration to mice and inhibition of [(35)S]TBPS binding to rat whole brain membranes, were compared with that of known anesthetic 3 alpha-hydroxypregnan-20-ones. Synthetic steroids with similar in vitro and in vivo activities to the endogenous 3 alpha-hydroxypregnan-20-ones all had an ether oxygen on the beta-face of the steroid D-ring. These results suggest that for optimal GABA(A) receptor modulation, the hydrogen bond-accepting substituent should be near perpendicular to the plane of the D-ring on the beta-face of the steroid.


Assuntos
Androstanóis/síntese química , Anestésicos/síntese química , Moduladores GABAérgicos/síntese química , Receptores de GABA-A/efeitos dos fármacos , Androstanóis/química , Androstanóis/farmacologia , Anestésicos/química , Anestésicos/farmacologia , Animais , Encéfalo/metabolismo , Moduladores GABAérgicos/química , Moduladores GABAérgicos/farmacologia , Ligação de Hidrogênio , Técnicas In Vitro , Injeções Intravenosas , Camundongos , Modelos Moleculares , Ensaio Radioligante , Ratos , Receptores de GABA-A/metabolismo , Relação Estrutura-Atividade
9.
J Invest Dermatol ; 110(1): 62-6, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9424089

RESUMO

Pemphigus vulgaris (PV) is an autoimmune blistering disease of the skin and is caused by autoantibodies against desmoglein 3 (Dsg3) on epidermal keratinocytes. Because the production of autoantibodies is presumably T cell dependent, Dsg3-specific T cell reactivity was investigated in 14 PV patients and 12 healthy donors. Peripheral blood mononuclear cells from seven PV patients with active disease showed a primary in vitro response to a recombinant protein containing the extracellular portion (EC1-5) of Dsg3, whereas two of seven PV patients in remission or under immunosuppressive treatment exhibited only secondary (2 degrees) or tertiary (3 degrees) T cell responses to Dsg3. T cell responses to Dsg3 were also observed in four of 12 healthy individuals upon 2 degrees or 3 degrees stimulation with Dsg3. Both PV patients and healthy responders were either positive for DRbeta1*0402 -- which is highly prevalent in PV -- or positive for DR11 alleles homologous to DRbeta1*0402. Two CD4+ Dsg3-specific T cell lines and 12 T cell clones from two PV patients and two CD4+ T cell lines and eight T cell clones from two normals were also stimulated by a Dsg3 protein devoid of the EC2-3 (deltaN1), suggesting that epitopes were located in the EC1, EC4, and/or EC5. Using Dsg3 peptides, one immunodominant peptide (residues 161-177) was also identified in the EC2. These observations demonstrate that T cell responses to Dsg3 can be detected in PV patients and in healthy donors carrying major histocompatibility class II alleles identical or similar to those highly prevalent in PV.


Assuntos
Caderinas/imunologia , Epitopos de Linfócito T/imunologia , Pênfigo/sangue , Especificidade de Anticorpos , Autoantígenos/sangue , Linfócitos T CD8-Positivos/imunologia , Citocinas/metabolismo , Desmogleína 3 , Epitopos , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Ativação Linfocitária/imunologia , Proteínas Recombinantes/imunologia , Toxoide Tetânico/imunologia , Toxoide Tetânico/farmacologia
10.
J Pharmacol Exp Ther ; 282(2): 513-20, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9262310

RESUMO

Xenovulene A (XR368) is a natural product exhibiting little structural resemblance with classical benzodiazepines yet is able to displace high-affinity ligand binding to the benzodiazepine site of the gamma-aminobutyric acid (GABA)A receptor. We have characterized this compound and an associated congener (XR7009) by use of radioligand binding and electrophysiological methodologies with native neurons and the Xenopus oocyte expression system. Xenovulene A, and the more potent XR7009, inhibited [3H]flunitrazepam binding to rat forebrain with Ki values of 7 and 192 nM, and 1.7 and 42 nM, respectively, each site accounting for approximately 50% of the total specific binding. In cerebellar and spinal cord membranes, these ligands identified only single binding sites. These ligands demonstrated no intrinsic agonist activity at recombinant GABA(A) receptors comprising alpha1beta1gamma2S subunits expressed in Xenopus oocytes, yet at 1 microM both significantly potentiated the GABA-induced response and reduced the GABA EC50 from 10.9 (control) to 5.1 (Xenovulene A) or 2.7 microM (XR7009). The rank potency order for enhancement of the 10 microM GABA response is: XR7009 (EC50, 0.02 microM) > diazepam (0.03) > Xenovulene A (0.05) > flurazepam (0.17). The activity of XR368 and XR7009 was reduced by the benzodiazepine antagonist, flumazenil, and absent in receptors devoid of the gamma2 subunit. These agents exhibited receptor subtype selectivity because alpha3beta1gamma2S receptors were less sensitive to these compounds relative to alpha1 subunit-containing receptors, whereas alpha6beta1gamma2S receptors were completely insensitive. Potentiation of the response to GABA on native GABA(A) receptors in cortical neurons substantiates the profile of the novel structures of Xenovulene A and XR7009 as specific benzodiazepine agonists.


Assuntos
Acremonium/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Receptores de GABA-A/efeitos dos fármacos , Sesquiterpenos/farmacologia , Animais , Neurônios/metabolismo , Ensaio Radioligante , Ratos , Ratos Wistar , Receptores de GABA-A/metabolismo , Receptores de GABA-A/fisiologia , Proteínas Recombinantes/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Xenopus laevis
11.
J Med Chem ; 40(11): 1668-81, 1997 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-9171876

RESUMO

(3 alpha,5 alpha)-3-Hydroxypregnan-20-ones and (3 alpha,5 alpha)-3-hydroxypregnane-11,20-diones bearing a 2 beta-morpholinyl substituent were synthesized, and the utility of these steroids as anesthetic agents was evaluated through determination of their potency and duration of hypnotic activity in mice after intravenous administration. Alkylation of the morpholinyl substituent or chlorination at C-21 afforded the novel amino steroids (2 beta,3 alpha,5 alpha)-3-hydroxy-2-(2,2-dimethyl-4-morpholinyl)-pregnane-11,20-dione (19) and (2 beta,3 alpha,5 alpha)-21-chloro-3-hydroxy-2-(4-morpholinyl)pregnan-20-one (37) that were more potent and advantageously produced shorter sleep times than related compounds which were previously reported. Furthermore, salts of these and other amino steroids generally retained good aqueous solubility. In a radioligand binding assay the compounds inhibited the specific binding of [35S]-tert-butyl bicyclophosphorothionate to rat whole brain membranes, and in an electrophysiological assay they potentiated GABAA receptor-mediated currents recorded from voltage-clamped bovine chromaffin cells. These in vitro results are consistent with the anesthetic activity of the amino steroids being related to their modulatory effects at GABAA receptors.


Assuntos
Anestesia , Anestésicos/síntese química , Morfolinas/síntese química , Pregnanodionas/síntese química , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/fisiologia , Animais , Encéfalo/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/metabolismo , Bovinos , Membrana Celular/metabolismo , Sistema Cromafim/fisiologia , Condutividade Elétrica , Eletrofisiologia , Masculino , Camundongos , Estrutura Molecular , Morfolinas/metabolismo , Morfolinas/farmacologia , Pregnanodionas/metabolismo , Pregnanodionas/farmacologia , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Solubilidade , Relação Estrutura-Atividade , Água
12.
J Neurochem ; 65(5): 1909-16, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7595473

RESUMO

Serotonin 5-HT1A receptors expressed stably in recombinant Chinese hamster ovary cells have been studied using radioligand binding with the radiolabelled agonist [3H]lisuride. Competition studies with a range of antagonists versus [3H]lisuride confirmed that all of the specific [3H]lisuride binding was to 5-HT1A receptors on the cells. Competition studies with the antagonist spiperone and several agonists gave data that fitted best to two-binding-site models. The affinities of these competing ligands at the two classes of sites were generally in agreement with their corresponding affinities determined in previous work with either 8-[3H]hydroxydipropylaminotetralin ([3H]8-OH-DPAT; labels receptor coupled to G protein) or [3H]spiperone (labels free receptor). Saturation analyses with [3H]lisuride showed that this radioligand labels a single class of binding sites, but the level of radioligand binding was approximately twice that seen when either [3H]8-OH-DPAT or [3H]spiperone was used. [3H]Lisuride binding was partially inhibited by addition of guanine nucleotides, and the extent of inhibition decreased as the [3H]lisuride concentration was increased. This inhibition was due to the effect of guanine nucleotide to decrease slightly the affinity of [3H]lisuride for binding to the 5-HT1A receptors on the cells. It is concluded that [3H]lisuride can label both the free receptor and the receptor coupled to G proteins but with slightly different affinities and that these two states of the receptor exist in roughly equal amounts in the cells. Agonists generally have a higher affinity for the receptor coupled to G protein, whereas antagonists, with the exception of spiperone (which has a higher affinity for the free receptor), have roughly equal affinities for the free receptor and the receptor coupled to G proteins.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Lisurida/metabolismo , Receptores de Serotonina/metabolismo , Animais , Células CHO , Membrana Celular/metabolismo , Cricetinae , Nucleotídeos de Guanina/farmacologia , Receptores de Serotonina/efeitos dos fármacos , Proteínas Recombinantes , Trítio
15.
Biochem Pharmacol ; 45(5): 1003-9, 1993 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-8461029

RESUMO

5HT1A serotonin (5-hydroxytryptamine) receptors have been characterized by ligand binding in a recombinant Chinese Hamster Ovary cell line expressing the human receptor gene. The agonist ligand [3H]2-(N,N-dipropylamino)-8-hydroxy-1,2,3,4-tetrahydronaphthalene ([3H]8-OH-DPAT) and the antagonist [3H]spiperone were used. For both radioligands the binding sites labelled have the properties of 5HT1A receptors and most antagonists show roughly equal affinities for the receptors labelled by either [3H]8-OH-DPAT or [3H]spiperone. Agonists, however, show higher affinities for the sites labelled by [3H]8-OH-DPAT and the antagonist spiperone conversely shows a higher affinity for the sites labelled by [3H]spiperone. Whereas [3H]8-OH-DPAT binding is inhibited by guanosine triphosphate (GTP) the binding of [3H]spiperone is increased by GTP. A model is proposed for the results whereby [3H]8-OH-DPAT labels a form of the receptor coupled to a G-protein and [3H]spiperone labels a form of the receptor uncoupled from G-proteins (or possibly coupled to a different G-protein).


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Receptores de Serotonina/metabolismo , Espiperona/metabolismo , 8-Hidroxi-2-(di-n-propilamino)tetralina/metabolismo , Animais , Células CHO , Cricetinae , Guanosina Trifosfato/farmacologia , Humanos , Ensaio Radioligante , Receptores de Serotonina/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Antagonistas da Serotonina , Trítio
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