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2.
Clin Otolaryngol ; 43(2): 477-482, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28981204

RESUMO

OBJECTIVE: To establish a real-time predictive scoring model based on sonographic characteristics for identifying malignant cervical lymph nodes (LNs) in cancer patients after neck irradiation. METHODS: One-hundred forty-four irradiation-treated patients underwent ultrasonography and ultrasound-guided fine-needle aspirations (USgFNAs), and the resultant data were used to construct a real-time and computerised predictive scoring model. This scoring system was further compared with our previously proposed prediction model. RESULTS: A predictive scoring model, 1.35 × (L axis) + 2.03 × (S axis) + 2.27 × (margin) + 1.48 × (echogenic hilum) + 3.7, was generated by stepwise multivariate logistic regression analysis. Neck LNs were considered to be malignant when the score was ≥ 7, corresponding to a sensitivity of 85.5%, specificity of 79.4%, positive predictive value (PPV) of 82.3%, negative predictive value (NPV) of 83.1%, and overall accuracy of 82.6%. When this new model and the original model were compared, the areas under the receiver operating characteristic curve (c-statistic) were 0.89 and 0.81, respectively (P < .05). CONCLUSIONS: A real-time sonographic predictive scoring model was constructed to provide prompt and reliable guidance for USgFNA biopsies to manage cervical LNs after neck irradiation.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/secundário , Linfonodos/patologia , Metástase Linfática/diagnóstico , Adulto , Idoso , Biópsia por Agulha Fina , Feminino , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Modelos Logísticos , Linfonodos/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Ultrassonografia
3.
Clin Otolaryngol ; 43(1): 124-130, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28556524

RESUMO

OBJECTIVE: Office-based laryngeal procedures (OBLPs) are emerging as effective alternative modalities for vocal disorders. This study systematically investigates the haemodynamic status of patients, specifically focusing on the potential effects of underlying comorbidity and medication use. DESIGN: Prospective cohort study. SETTING: Tertiary referral centre. PARTICIPANTS: We prospectively recruited 214 consecutive patients who received OBLPs during January-December 2015. All procedures were performed under local anaesthesia without sedation, in an upright (sitting) position. MAIN OUTCOME MEASURES: We measured heart rate (HR), systolic and diastolic blood pressure, and oxygen saturations at baseline (before procedure), immediately after local anaesthesia to the pharynx and larynx, immediately after completing of procedure, and 20 minutes after the procedure. RESULTS: Systolic, diastolic blood pressures and HR all significantly increased after local anaesthesia, and gradually decreased after the procedure (P<.01). Oxygen concentration remained unchanged. Patients with comorbidity and those receiving vasoactive medications showed significantly higher perioperative blood pressures than the other patients (P<.05), but the trend remained similar. Prominent hypertension (systolic ≥160 mm Hg or diastolic ≥100 mm Hg) was noted in 17 patients, more commonly in patients with older age, higher baseline blood pressures and receiving vasoactive medications. Only 2% of patients with normal baseline measurements developed prominent hypertension perioperatively. Tachycardia (HR≥100 bpm) developed in 22 patients, more frequently in patients with higher baseline HRs, and perceiving greater discomforts. CONCLUSION: This study revealed that routine haemodynamic monitoring may not be necessary for all the OBLPs, but should be considered for older patients, those with higher baseline blood pressure or HR, sensitive patients who might be more susceptible to perioperative discomfort, and those receiving vasoactive medications.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hemodinâmica/fisiologia , Hipertensão/epidemiologia , Doenças da Laringe/epidemiologia , Laringoscopia , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade/tendências , Feminino , Seguimentos , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Doenças da Laringe/terapia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taiwan/epidemiologia , Adulto Jovem
4.
Clin Otolaryngol ; 43(2): 463-469, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28950051

RESUMO

OBJECTIVES: Nasopharyngeal cancer (NPC) is an endemic disease in Taiwan. Prognostic factors the anatomical TNM stage are important for its prognostic stratification. An elevated neutrophil-to-lymphocyte ratio (NLR) has been reported to be associated with poor prognosis in various solid tumours. In this study, we analysed the prognostic impact of the NLR in NPC in Taiwan. DESIGN: Single-institution retrospective study. SETTING: Medical centre. PARTICIPANTS: One hundred and eighty patients with NPC treated at the Far Eastern Memorial Hospital, Taiwan, from January 2007 to December 2013. MAIN OUTCOME MEASURES: The association between the clinical or haematological presentations and the prognosis. RESULTS: The majority of the 180 patients included in this study were men (80%) and were <65 years old (91.7%). A neck mass (55.6%) was the most common clinical presentation, followed by nasal (39.4%) and aural (30.6%) symptoms. In addition, the majority (75.4%) of patients had advanced stage (III and IV) disease. Patients with a high NLR (≧3.6) had significantly lower progression-free survival, overall survival and disease-specific survival rates. The association between high NLR and poor prognosis was more pronounced in patients with advanced disease than in those with early-stage NPC. The results of a multivariate analysis revealed that advanced age, clinical symptoms including headache, diplopia and facial numbness, advanced disease stage, and high NLR were independent prognostic factors. CONCLUSION: A high NLR is an independent poor prognostic factor of NPC in Taiwan.


Assuntos
Povo Asiático , Contagem de Linfócitos , Carcinoma Nasofaríngeo/sangue , Carcinoma Nasofaríngeo/mortalidade , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/mortalidade , Neutrófilos , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Taiwan , Adulto Jovem
5.
Hong Kong Med J ; 23(5): 454-61, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28416733

RESUMO

INTRODUCTION: In all cases of suspected child abuse, accurate risk assessment is vital to guide further management. This study examined the relationship between risk factors in a risk assessment matrix and child abuse case conference outcomes. METHODS: Records of all children hospitalised at United Christian Hospital in Hong Kong for suspected child abuse from January 2012 to December 2014 were reviewed. Outcomes of the hospital abuse work-up as concluded in the Multi-Disciplinary Case Conference were categorised as 'established', 'high risk', or 'not established'. All cases of 'established' and 'high risk' were included in the positive case conference outcome group and all cases of 'not established' formed the comparison group. On the other hand, using the Risk Assessment Matrix developed by the California State University, Fresno in 1990, each case was allotted a matrix score of low, intermediate, or high risk in each of 15 matrix domains, and an aggregate matrix score was derived. The effect of individual matrix domain on case conference outcome was analysed. Receiver operating characteristic curve analysis was used to examine the relationship between case conference outcome and aggregate matrix score. RESULTS: In this study, 265 children suspected of being abused were included, with 198 in the positive case conference outcome group and 67 in the comparison group. Three matrix domains (severity and frequency of abuse, location of injuries, and strength of family support systems) were significantly associated with case conference outcome. An aggregate cut-off score of 23 yielded a sensitivity of 91.4% and specificity of 38.2% in relation to outcome of abuse categorisation. CONCLUSIONS: Risk assessment should be performed when handling suspected child abuse cases. A high aggregate score should arouse suspicion in all disciplines managing child abuse cases.


Assuntos
Maus-Tratos Infantis/estatística & dados numéricos , Equipe de Assistência ao Paciente , Medição de Risco , Visitas de Preceptoria , Benchmarking , Estudos de Casos e Controles , Criança , Maus-Tratos Infantis/prevenção & controle , Serviços de Saúde da Criança/normas , Prestação Integrada de Cuidados de Saúde/normas , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Curva ROC , Estudos Retrospectivos , Fatores de Risco
7.
AJNR Am J Neuroradiol ; 44(2): 125-133, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36702502

RESUMO

BACKGROUND AND PURPOSE: A scout accelerated motion estimation and reduction (SAMER) framework has been developed for efficient retrospective motion correction. The goal of this study was to perform an initial evaluation of SAMER in a series of clinical brain MR imaging examinations. MATERIALS AND METHODS: Ninety-seven patients who underwent MR imaging in the inpatient and emergency department settings were included in the study. SAMER motion correction was retrospectively applied to an accelerated T1-weighted MPRAGE sequence that was included in brain MR imaging examinations performed with and without contrast. Two blinded neuroradiologists graded images with and without SAMER motion correction on a 5-tier motion severity scale (none = 1, minimal = 2, mild = 3, moderate = 4, severe = 5). RESULTS: The median SAMER reconstruction time was 1 minute 47 seconds. SAMER motion correction significantly improved overall motion grades across all examinations (P < .005). Motion artifacts were reduced in 28% of cases, unchanged in 64% of cases, and increased in 8% of cases. SAMER improved motion grades in 100% of moderate motion cases and 75% of severe motion cases. Sixty-nine percent of nondiagnostic motion cases (grades 4 and 5) were considered diagnostic after SAMER motion correction. For cases with minimal or no motion, SAMER had negligible impact on the overall motion grade. For cases with mild, moderate, and severe motion, SAMER improved the motion grade by an average of 0.3 (SD, 0.5), 1.1 (SD, 0.3), and 1.1 (SD, 0.8) grades, respectively. CONCLUSIONS: SAMER improved the diagnostic image quality of clinical brain MR imaging examinations with motion artifacts. The improvement was most pronounced for cases with moderate or severe motion.


Assuntos
Pacientes Internados , Imageamento por Ressonância Magnética , Humanos , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Movimento (Física) , Artefatos , Processamento de Imagem Assistida por Computador/métodos
8.
Energy (Oxf) ; 36(2): 1134-1142, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32288043

RESUMO

A number of Asian cities decided to establish gaming and resort facilities in order to capitalize on the growing number of gamblers and their family members in Asia. In doing so, they expect to sustain economic growth but, on the other hand, will consume a considerable amount of energy. Nevertheless, the causal relationship between economic growth and electricity consumption in this type of service-oriented territories has never been investigated. Using the historical data obtained from the Government of Macao SAR, we found that electricity consumption and economic growth in terms of gross domestic product are co-integrated for the period of 1999 Quarter 1-2008 Quarter 4. Moreover, vector error correction (VEC) models indicated a lack of short-run relationships but showed that there was a long-run equilibrium relationship between electricity consumption and gross domestic product. The accuracy of VEC models was assessed by using the mean squared error and the mean absolute error. The error analysis shows that VEC models reproduced time series of gross domestic product and electricity consumption in difference form accurately.

9.
AJNR Am J Neuroradiol ; 42(9): 1584-1590, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244127

RESUMO

BACKGROUND AND PURPOSE: Our aim was to evaluate an ultrafast 3D-FLAIR sequence using Wave-controlled aliasing in parallel imaging encoding (Wave-FLAIR) compared with standard 3D-FLAIR in the visualization and volumetric estimation of cerebral white matter lesions in a clinical setting. MATERIALS AND METHODS: Forty-two consecutive patients underwent 3T brain MR imaging, including standard 3D-FLAIR (acceleration factor = 2, scan time = 7 minutes 50 seconds) and resolution-matched ultrafast Wave-FLAIR sequences (acceleration factor = 6, scan time = 2 minutes 45 seconds for the 20-channel coil; acceleration factor = 9, scan time = 1 minute 50 seconds for the 32-channel coil) as part of clinical evaluation for demyelinating disease. Automated segmentation of cerebral white matter lesions was performed using the Lesion Segmentation Tool in SPM. Student t tests, intraclass correlation coefficients, relative lesion volume difference, and Dice similarity coefficients were used to compare volumetric measurements among sequences. Two blinded neuroradiologists evaluated the visualization of white matter lesions, artifacts, and overall diagnostic quality using a predefined 5-point scale. RESULTS: Standard and Wave-FLAIR sequences showed excellent agreement of lesion volumes with an intraclass correlation coefficient of 0.99 and mean Dice similarity coefficient of 0.97 (SD, 0.05) (range, 0.84-0.99). Wave-FLAIR was noninferior to standard FLAIR for visualization of lesions and motion. The diagnostic quality for Wave-FLAIR was slightly greater than for standard FLAIR for infratentorial lesions (P < .001), and there were fewer pulsation artifacts on Wave-FLAIR compared with standard FLAIR (P < .001). CONCLUSIONS: Ultrafast Wave-FLAIR provides superior visualization of infratentorial lesions while preserving overall diagnostic quality and yields white matter lesion volumes comparable with those estimated using standard FLAIR. The availability of ultrafast Wave-FLAIR may facilitate the greater use of 3D-FLAIR sequences in the evaluation of patients with suspected demyelinating disease.


Assuntos
Encéfalo , Substância Branca , Artefatos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Humanos , Imageamento por Ressonância Magnética , Movimento (Física) , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
10.
Neuroscience ; 159(2): 727-34, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19167463

RESUMO

Neuronal nitric oxide synthases (nNOS) is distributed throughout the central nervous system (CNS) and has been proposed to modulate neuronal activity in the nucleus tractus solitarii (NTS). Here, we investigated whether the activation of nNOS is involved in insulin-induced cardiovascular responses in the NTS. Insulin (100 IU/ml) was unilaterally microinjected into the NTS, and the cardiovascular effects were evaluated before and after microinjection of the nNOS inhibitors 7-nitroindazole (7-NI) (5 pmol) and N(5)-(1-imino-3-butenyl)-l-ornithine (vinyl-L-NIO) (600 pmol). Western blot and immunohistochemical analyses were performed to determine nNOS phosphorylation levels after insulin or phosphoinositide 3-kinase (PI3K) inhibitor LY294002 microinjection into the NTS. Unilateral microinjection of insulin into the NTS produced prominent depressor and bradycardic effects in WKY rats. Pretreatment with the nNOS inhibitors 7-NI and Vinyl-L-NIO attenuated the cardiovascular response evoked by insulin in Wistar-Kyoto (WKY) rats. Moreover, Western blot analysis showed a significant increase in nNOS (16.5+/-0.4-fold; P<0.05; n=4) phosphorylation after insulin injection, whereas the PI3K inhibitor LY294002 abolished the insulin-induced effects. In situ nNOS phosphorylation was found to be increased in the NTS after insulin injection. Furthermore, co-immunoprecipitation assay showed Akt and nNOS can bind to each other as detected by phospho-Akt(S473) and phospho-nNOS(S1416) antibodies. In vitro kinase assay showed insulin activated Akt can directly phosphorylate nNOS(S1416). These results demonstrated that nNOS may couple with the activation of the insulin receptor, via the liberation of NO, in order to participate in central cardiovascular regulation of WKY rats.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Insulina/farmacologia , Óxido Nítrico Sintase Tipo I/metabolismo , Núcleo Solitário/efeitos dos fármacos , Análise de Variância , Animais , Cromonas/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Frequência Cardíaca/efeitos da radiação , Imunoprecipitação/métodos , Indazóis/farmacologia , Masculino , Microinjeções/métodos , Morfolinas/farmacologia , Ornitina/análogos & derivados , Ornitina/farmacologia , Ratos , Ratos Endogâmicos WKY , Núcleo Solitário/enzimologia
15.
Oncogene ; 18(54): 7765-74, 1999 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-10618717

RESUMO

We have identified a novel p53 regulated gene designated DDA3 through differential mRNA display on IW32 erythroleukemia cells containing a temperature sensitive p53 allele, tsp53val-135. DDA3 mRNA induction could be observed in all sublines expressing tsp53val-135 cultured at permissive temperature as well as in NIH3T3 cells undergoing DNA damage. Upregulation of DDA3 could be detected within 2 h after down-shifting the temperature to 32.5 degrees C; upon shifting back to 38.5 degrees C, DDA3 mRNA rapidly degraded with a half-life of less than 2 h. Actinomycin D, but not cycloheximide, inhibited the p53 dependent DDA3 induction, suggesting that the activation is through transcriptional regulation and does not require de novo protein synthesis. DDA3 was expressed in multiple mouse tissues including brain, spleen, lung, kidney and testis. Full-length DDA3 cDNA was cloned and it contained an open reading frame predicted to encode a proline rich protein of 329 amino acids. Overexpression of DDA3 in H1299 lung carcinoma cells suppressed colony formation. These results suggest that DDA3 is a p53-regulated gene that might participate in the p53-mediated growth suppression.


Assuntos
Regulação da Expressão Gênica , Fosfoproteínas/genética , RNA Mensageiro/genética , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas , Núcleo Celular/metabolismo , Clonagem Molecular , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Eritroblástica Aguda , Neoplasias Pulmonares , Masculino , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , Fosfoproteínas/biossíntese , Fosfoproteínas/química , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo
16.
Arch Intern Med ; 158(1): 54-8, 1998 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-9437379

RESUMO

BACKGROUND: A blood clot in a peptic ulcer is unstable in a low pH environment. The use of omeprazole may prevent rebleeding by elevating intragastric pH in patients with bleeding peptic ulcer after hemostasis has been achieved. OBJECTIVES: To assess the influence of using omeprazole and cimetidine on 24-hour intragastric pH and to determine their ability to prevent rebleeding after having achieved initial hemostasis in patients with active bleeding or nonbleeding visible vessels. METHODS: One hundred patients with bleeding peptic ulcers who had obtained initial hemostasis were enrolled in this randomized comparative trial. In the cimetidine group (n = 50), a 300-mg intravenous bolus of cimetidine was given, followed by a 1200-mg continuous infusion daily for 3 days. Thereafter, 400 mg of cimetidine was given orally twice daily for 2 months. In the omeprazole group (n = 50), a 40-mg intravenous bolus of omeprazole was given, followed by 160 mg of continuous infusion daily for 3 days. Thereafter, 20 mg of omeprazole was given orally once daily for 2 months. A pH meter was inserted in each patient's fundus under fluoroscopic guidance after the intravenous bolus of cimetidine or omeprazole had been administered. RESULTS: The stigmata of recent hemorrhage before endoscopic therapy in the omeprazole and cimetidine groups were, respectively, spurting (9 vs 12), oozing (4 vs 9), and nonbleeding visible vessel (37 vs 29) (P > .05). The duration of intragastric pH higher than 6.0 was longer in the omeprazole group (mean [+/- SD], 84.4% +/- 22.9%) than that of the cimetidine group (mean [+/- SD], 53.5% +/- 32.3%) (P < .001). Rebleeding occurred in 2 patients (4%) in the omeprazole group and in 12 patients (24%) in the cimetidine group by day 14 after enrollment (P = .004). There was a tendency for patients in the omeprazole group to require less blood transfusion (median, 0 mL; range, 0-2500 mL) than those in the cimetidine group (median, 0 mL; range, 0-5000 mL) (P = .08). The hospital stay and number of operations and mortality rate were similar between both groups. CONCLUSIONS: The use of omeprazole is more effective than cimetidine in increasing intragastric pH and reducing rebleeding episodes in patients with bleeding peptic ulcers after successful endoscopic therapy. This suggests that omeprazole should be used routinely after successful endoscopic therapy.


Assuntos
Antiulcerosos/uso terapêutico , Cimetidina/uso terapêutico , Hemorragia Gastrointestinal/prevenção & controle , Omeprazol/uso terapêutico , Úlcera Péptica/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transfusão de Sangue , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/mortalidade , Hemorragia Gastrointestinal/terapia , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Resultado do Tratamento
17.
Hypertension ; 35(6): 1253-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10856273

RESUMO

Recent studies suggest that carbon monoxide (CO), which is produced in significant quantities in many brain regions, may function as a neurotransmitter. Heme oxygenase catalyzes the metabolism of heme to CO and biliverdin; however, the physiological role of CO in central cardiovascular regulation was not well understood. In the present study, we evaluated the baroreflex response of CO in the nucleus tractus solitarii (NTS) of rats. Male Sprague-Dawley rats were anesthetized with urethane, and blood pressure and heart rate were monitored intra-arterially. Unilateral microinjection (60 nL) of hematin, a heme molecule cleaved by heme oxygenase to yield CO, into the NTS produced prominent dose-related depressor and bradycardic effects. Baroreflex responses were elicited by increasing doses of phenylephrine (10 to 30 microg/kg IV) before and after intra-NTS administration of zinc deuteroporphyrin 2,4-bis-glycol (ZnDPBG) (1 nmol), an inhibitor of heme oxygenase activity, or vehicle alone. The reflex bradycardia elicited by phenylephrine was significantly inhibited by pretreatment with ZnDPBG. Furthermore, the inhibitory effect of ZnDPBG on baroreflex activation was dose dependent. These results suggest CO formed by brain heme oxygenase plays a significant role in central cardiovascular regulation and that inhibition of heme oxygenase attenuated baroreflex activation.


Assuntos
Barorreflexo/efeitos dos fármacos , Monóxido de Carbono/farmacologia , Núcleo Solitário/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Deuteroporfirinas/farmacologia , Relação Dose-Resposta a Droga , Frequência Cardíaca/efeitos dos fármacos , Hemina/farmacologia , Masculino , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley
18.
Hypertension ; 30(6): 1499-503, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9403573

RESUMO

Nitric oxide (NO) is an endogenously synthesized effector molecule that acts as a neurotransmitter with novel properties in both the central and peripheral nervous systems. We previously reported that NO was involved in central cardiovascular regulation and modulated the baroreflex in the nucleus tractus solitarii (NTS) of rats. The aim of the present study was to determine whether NO and excitatory amino acids reciprocally release each other in the NTS. In normotensive Sprague-Dawley rats, intra-NTS microinjection of L-arginine (1 to 100 nmol/60 nL) produced a dose-dependent decrease in blood pressure and heart rate. Microinjection of excitatory amino acids L-glutamate and NMDA also produced depressor and bradycardic effects. These effects of L-glutamate or NMDA were blocked by prior administration of NO synthase inhibitor N(G)-methyl-L-arginine or N(G)-nitro-L-arginine methyl ester. Similarly, prior administration of N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 and non-NMDA receptor antagonist 6,7-dinitroquinoxaline-2,3-dione significantly attenuated the depressor and bradycardic effect of L-arginine. These results demonstrated a reciprocal attenuation of NO synthase inhibitor and NMDA receptor antagonist on NMDA and L-arginine responses, respectively, in the NTS and suggest that NO and NMDA receptors may interact in central cardiovascular regulation.


Assuntos
Arginina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Mapeamento Encefálico , Ácido Glutâmico/farmacologia , Frequência Cardíaca/efeitos dos fármacos , N-Metilaspartato/farmacologia , Óxido Nítrico/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Núcleo Solitário/fisiologia , Animais , Arginina/administração & dosagem , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/fisiologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Ácido Glutâmico/administração & dosagem , Masculino , Microinjeções , N-Metilaspartato/administração & dosagem , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Quinoxalinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Núcleo Solitário/efeitos dos fármacos , ômega-N-Metilarginina/farmacologia
19.
Hypertension ; 32(6): 1034-8, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9856969

RESUMO

It has been shown that nitric oxide (NO) is synthesized in the central nervous system as well as in vascular endothelial cells. We recently reported that NO was involved in central cardiovascular regulation, modulated the baroreflex, and was involved in a reciprocal release with excitatory amino acids in the nucleus tractus solitarii (NTS) of rats. We also reported previously that adenosine increased the release of glutamate in the NTS. The purpose of the present study was to investigate the possible interaction of NO and adenosine in the NTS. Male Sprague-Dawley rats were anesthetized with urethane, and blood pressure was monitored intra-arterially. Unilateral microinjection of L-arginine (3.3 nmol/60 nL) into the NTS produced decreases in blood pressure and heart rate. Microinjection of adenosine (2.3 nmol/60 nL) also produced depressive and bradycardic effects. These cardiovascular effects were attenuated by prior administration of the specific adenosine receptor antagonist DPSPX (0.92 nmol). Similarly, prior administration of NO synthase inhibitor NG-monomethyl-L-arginine or NG-nitro-L-arginine methyl ester significantly attenuated the depressive and bradycardic effects of adenosine. These results demonstrate a reciprocal attenuation of adenosine receptor antagonist and NO synthase inhibitor on L-arginine and adenosine responses, respectively, in the NTS and implicate an interaction between NO and adenosine in central cardiovascular regulation.


Assuntos
Adenosina/farmacologia , Fármacos Cardiovasculares/farmacologia , Óxido Nítrico/antagonistas & inibidores , Núcleo Solitário/efeitos dos fármacos , Adenosina/antagonistas & inibidores , Animais , Arginina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Masculino , Microinjeções , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Cloreto de Sódio , Xantinas , ômega-N-Metilarginina/farmacologia
20.
J Immunol Methods ; 128(1): 17-25, 1990 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-2157766

RESUMO

We describe here a novel immunoassay procedure, designated strip-ELISA (S-ELISA), in which specific antigens are purified by SDS-PAGE, transferred to support membranes, and utilized in situ as substrate in routine ELISA procedures. Using two different lentivirus systems, simian immunodeficiency virus and equine infectious anemia virus, we demonstrate the utility of S-ELISA for screening hybridoma supernatants during production of monoclonal antibodies and for the dissection of polyclonal antibody responses into defined antigen specificities. The data presented here indicates that the S-ELISA combines the sensitivity of conventional ELISA with the specificity afforded by Western blotting procedures, producing a relatively simple and versatile assay for evaluating antibody reactivities.


Assuntos
Anticorpos Antivirais/análise , Ensaio de Imunoadsorção Enzimática , Animais , Western Blotting , Hibridomas , Soros Imunes/imunologia , Vírus da Anemia Infecciosa Equina/imunologia , Camundongos
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