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1.
Diabet Med ; 31(4): 466-71, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24102923

RESUMO

AIMS: Islet cell autoantibodies are associated with autoimmune insulitis and belong to the diagnostic criteria of type 1 diabetes mellitus. However, growing evidence suggests that autoantibodies are present in other types of diabetes. Here, we focus on the autoantibody incidence in Czech patients with maturity-onset diabetes of the young and analyse their functional relevance in terms of diabetes onset and control. METHODS: Autoantibodies against glutamic acid decarboxylase (GAD) 65 and protein tyrosine phosphatase islet antigen 2 (IA-2) were measured in a cohort of 28 Czech patients with maturity-onset diabetes of the young, all confirmed by genetic testing. Selected clinical data were correlated to the status and kinetics of autoantibodies. RESULTS: One quarter of patients with maturity-onset diabetes of the young examined (7/28; 25%) was positive for GAD or IA-2 autoantibodies. GAD autoantibodies were more prevalent (7/7) than IA-2 autoantibodies (1/7). The incidence of autoantibodies did not correlate with human leukocyte antigen status. The patients who were positive for the autoantibodies developed diabetes later than those who were autoantibody-negative, but had worse glycaemic control (increased HbA1c ). Expression of autoantibodies decreased with any improvement of diabetes compensation. Only one patient did not correspond to the above and displayed signs of combined signs of maturity-onset diabetes of the young and Type 1 diabetes. CONCLUSIONS: The data suggest transient but highly prevalent islet cell autoantibody expression in Czech patients with maturity-onset diabetes of the young. The autoantibodies were found in patients with delayed diabetes onset, and in times of insufficient diabetes control. As improvement of glycaemic control was associated with a decrease in levels of autoantibodies, their presence may reflect the kinetics of ß-cell destruction induced by causes other than autoimmune ones.


Assuntos
Autoanticorpos/imunologia , Diabetes Mellitus Tipo 2/imunologia , Glutamato Descarboxilase/imunologia , Hemoglobinas Glicadas/metabolismo , Ilhotas Pancreáticas/imunologia , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores/imunologia , Adolescente , Adulto , Idade de Início , Criança , Estudos de Coortes , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Glucoquinase/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/genética , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
2.
Eur J Radiol Open ; 10: 100488, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168316

RESUMO

Background: The evaluation of DWI/FLAIR mismatch in ischaemic stroke patients with unknown, time from onset can determine the treatment strategy. This approach is based on, visual assessment and may be subject to insufficient inter-rater agreement. Objective: To compare the inter-rater agreement of visual evaluation of FLAIR MRI and proposed region of interest (ROI) semiquantitative method in large vessel occlusion (LVO) strokes. Methods: Five readers have analysed MRIs of 104 patients obtained within six hours of the onset of stroke symptoms resulting from LVO visually and semi-quantitatively. For the semiquantitative analysis, a ROI method was used to obtain relative signal intensity compared to the unaffected side. Cut-off values of 1.15 and 1.10 were tested. The analysis yielded FLAIR-positive (abnormal) and negative (normal) findings. Percentage agreement and Fleiss kappa coefficients were calculated. Results: The visual agreement of 5/5 readers and ≥ 4/5 readers occurred in 31% and 59% of cases respectively. Semi-quantitative evaluation using a cut-off value of 1.15 increased the agreements to 67% and 88% respectively. The agreement of visual evaluation was fair. The semi-quantitative method utilising the cut-off of 1.15 had moderate agreement although it increased the number of FLAIR-negative results compared to the visual evaluation. A low cut-off value of 1.10 didn't improve the agreement significantly. Conclusion: The inter-rater agreement of visual evaluation of FLAIR in patients with short-duration large vessel occlusion stroke was fair. The high cut-off value of semiquantitative evaluation increased the agreement although it changed the proportion of FLAIR positive and negative results.

3.
Artigo em Inglês | MEDLINE | ID: mdl-20461965

RESUMO

OBJECTIVE: At present, no reliable in vitro test is available to monitor the success of specific venom immunotherapy (VIT) in preventing insect venom anaphylaxis. We investigated usefulness of the basophil activation test (BAT) in predicting the outcome of sting challenge in bee venom-allergic patients after VIT. PATIENTS AND METHODS: Twenty-one patients with bee venom anaphylaxis at the end of VIT and 6 control participants were enrolled. BAT (flow-cytometric evaluation of allergen-induced expression of CD63), skin testing, and specific immunoglobulin (Ig) E determination were performed prior to sting challenge. RESULTS: Five of the 21 patients (23.8%) reacted to sting challenge. At a bee venom concentration of 100 ng/mL, the mean proportion of basophils expressing CD63 was 56% in reactors and 13.2% in nonreactors (P = .0321). Four of the 5 reactors had positive results and 14 of the 16 nonreactors had negative results. Thus, using 18.4% and 21.6% (receiver operating characteristic curve analysis) as the cutoff for expression of the CD63 marker, the positive and the negative predictive values were 67% and 93%, respectively, and specificity and sensitivity for BAT were 80% and 83%, respectively. However, at a concentration of 1000 ng/mL, no significant differences in basophil activation were observed between reactors and nonreactors. CONCLUSION: We found BAT to be a helpful tool in predicting the clinical sensitivity of bee venom-allergic patients after VIT (correlation between BAT at submaximal venom concentration and sting challenge).


Assuntos
Anafilaxia/imunologia , Anafilaxia/terapia , Teste de Degranulação de Basófilos , Basófilos/metabolismo , Dessensibilização Imunológica , Adulto , Alérgenos/imunologia , Alérgenos/uso terapêutico , Anafilaxia/diagnóstico , Antígenos CD/imunologia , Antígenos CD/metabolismo , Basófilos/imunologia , Basófilos/patologia , Venenos de Abelha/imunologia , Venenos de Abelha/uso terapêutico , Biomarcadores/metabolismo , Separação Celular , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Glicoproteínas da Membrana de Plaquetas/imunologia , Glicoproteínas da Membrana de Plaquetas/metabolismo , Valor Preditivo dos Testes , Prognóstico , Sensibilidade e Especificidade , Tetraspanina 30
4.
Phytother Res ; 23(8): 1169-74, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19165752

RESUMO

The aim of this study was to describe the effects of Pycnogenol at various doses on preprandial and postprandial glucose levels, the levels of thiobarbituric acid reactive substances (TBARs) and N-acetyl-beta-d-glucosaminidase (NAGA) and on motor nerve conduction velocity (MNCV) in streptozotocin (STZ)-induced diabetic rats. Pycnogenol treatment (10, 20, 50 mg/kg body weight (b.w.)/day) lasted for 8 weeks after induction of diabetes. Pycnogenol significantly decreased elevated levels of preprandial glycaemia in treated animals at all doses. At doses of 10 mg/kg b.w./day and 20 mg/kg b.w./day it significantly decreased elevated levels of postprandial glycaemia compared with diabetic non-treated animals. Pycnogenol failed to induce a significant decrease of postprandial glycaemia at a dose of 50 mg/kg b.w./day. Pycnogenol improved significantly the impaired MNCV at doses of 10 and 20 mg/kg b.w./day compared with non-treated animals. The levels of TBARs were elevated in diabetic rats. The levels of NAGA increased gradually despite the treatment. Pycnogenol failed to affect the increased levels of TBARs and NAGA. Pycnogenollowered the elevated levels of glycaemia and reduced the decline in motor nerve conduction velocity in STZ-induced diabetic rats. The effect of Pycnogenol on postprandial glycaemic levels and MNCV was not dose-dependent.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Flavonoides/farmacologia , Condução Nervosa/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Acetilglucosaminidase/metabolismo , Animais , Glicemia , Relação Dose-Resposta a Droga , Masculino , Extratos Vegetais , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
5.
Int J Immunogenet ; 35(2): 133-40, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18279373

RESUMO

Both the human leucocyte antigen (HLA) DRB1 and the HLA DQB1 gene loci play a role in the development and progression of autoimmune diabetes mellitus (T1DM). Similarly, the insulin promoter variable number tandem repeats (INS-VNTR) polymorphism is also involved in the pathogenesis of diabetes mellitus (DM). We studied the association between each of these polymorphisms and DM diagnosed in patients older than age 35 years. Furthermore, we analysed possible interactions between HLA DRB1/DQB1 and INS-VNTR polymorphisms. Based on C-peptide and GADA levels we were able to distinguish three types of diabetes: T1DM, latent autoimmune diabetes in adults (LADA) and T2DM. INS-VNTR was genotyped indirectly by typing INS-23HphI A/T polymorphism. The genotype and allele frequencies of INS-23HphI did not differ between each of the diabetic groups and group of healthy subjects. We did, however, observe an association between the INS-23HphI alleles, genotypes and C-peptide secretion in all diabetic patients: A allele frequency was 86.2% in the C-peptide-negative group vs. 65.4% in the C-peptide-positive group (P(corr.) < 0.005); AA genotype was found to be 72.4% in the C-peptide-negative group vs. 42.6% in the C-peptide-positive groups (P(corr.) < 0.01). The HLA genotyping revealed a significantly higher frequency of HLA DRB1*03 allele in both T1DM and LADA groups when compared to healthy subjects: T1DM (25.7%) vs. control group (10.15%), odds ratio (OR) = 3.06, P < 0.05; LADA (27.6%) vs. control (10.15%), OR = 3.37, P < 0.01. The simultaneous presence of both HLA DRB1*04 and INS-23HphI AA genotype was detected in 37.5% of the T1DM group compared to only 9.2% of the healthy individuals group (OR = 5.9, P(corr.) < 0.007). We summarize that in the Central Bohemian population of the Czech Republic, the INS-23HphI A allele appears to be associated with a decrease in pancreatic beta cell secretory activity. HLA genotyping points to at least a partial difference in mechanism, which leads to T1DM and LADA development as well as a more diverse genetic predisposition in juvenile- and adult-onset diabetes. The simultaneous effect of HLA and INS-VNTR alleles/genotypes predispose individuals to an increased risk of diabetes development.


Assuntos
Diabetes Mellitus Tipo 1/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Insulina/genética , Repetições Minissatélites/genética , Polimorfismo Genético , Regiões Promotoras Genéticas/genética , Adulto , Idade de Início , Alelos , República Tcheca , Diabetes Mellitus Tipo 1/imunologia , Feminino , Frequência do Gene/genética , Frequência do Gene/imunologia , Predisposição Genética para Doença , Antígenos HLA-DQ/imunologia , Cadeias beta de HLA-DQ , Antígenos HLA-DR/imunologia , Cadeias HLA-DRB1 , Humanos , Insulina/imunologia , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites/imunologia , Regiões Promotoras Genéticas/imunologia , Fatores de Risco
6.
Ann Nutr Metab ; 53(2): 129-36, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18997461

RESUMO

AIM: In this study, we tested the impact of short-term intake of increased amounts of C18:1 trans fatty acids (TFAs) on parameters of cellular and humoral immunity in healthy young men. METHODS: Twenty-seven healthy young men were subsequently exposed to a standard diet for 7 days and an experimental TFA-enriched diet for 4 days. The mean energy content of these diets was 2,453 and 2,455 kcal/day, with 10, 35 and 55% of energy from proteins, fats and carbohydrates, respectively. Standard diet contained about 0.8 g and experimental diet 10.4 g TFAs. Plasma levels of C18:1 TFAs and immunological parameters were measured. RESULTS: The 4-day increased consumption of C18:1 TFAs led to a significant decrease in mitogen-induced CD69 expression on CD8+ T cells as well as decreased phagocytic activity on neutrophils. After returning to the participants' habitual diet (1 week after the end of the experimental diet), we observed a significant decrease in the mean level of circulating immune complexes. Concentrations of plasma immunoglobulins remained unchanged throughout the study. CONCLUSIONS: Acute impact of higher dietary C18:1 TFA intake on phagocytosis and cell-mediated immunity seems to be suppressive. This finding differs from results describing proinflammatory effects associated with long-term exposure to TFAs.


Assuntos
Formação de Anticorpos/efeitos dos fármacos , Imunidade Celular/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Ácidos Graxos trans/administração & dosagem , Ácidos Graxos trans/imunologia , Estudos Cross-Over , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Masculino , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Explosão Respiratória/efeitos dos fármacos , Ácidos Graxos trans/sangue , Adulto Jovem
7.
Bratisl Lek Listy ; 109(4): 177-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18814435

RESUMO

UNLABELLED: Carpal tunnel syndrome (CTS) is the most common form of peripheral nerve entrapment. Electromyography with selected nerve conduction studies (NCS) is an accepted diagnostic tool in CTS patients. Ultrasonography presents a widely available and low cost investigation method and its position in CTS diagnostics needs further clarification with concrete recommendations for clinical practice. A prospective study of 37 patients with 74 wrists (59 wrists with suspected CTS) was done. Normative data were obtained from a control group of 25 healthy persons (50 wrists) age and sex matched. All persons underwent ultrasonographic examination (median nerve cross-sectional area at carpal tunnel entrance measurement--CSA) and median NCS studies (distal motor and sensory latency measurement--DML and DSL). RESULTS: CSA has a sensitivity of 93% (CI 84-97%) and specificity of 96% (CI 87-99%) in our patients group. Conventional first-line NCS studies results in our patients groupare as follows: DML sensitivity 58% (CI 45-69%) and specificity 100% (CI 93-100%); DSL sensitivity 88% (CI 78-94%) and specificity 94% (CI 84-98%). CONCLUSION: We recommend the use of single-parameter wrist ultrasonography as a first-line screening laboratory method in suspected CTS diagnosis (Ref. 14). Full Text (Free, PDF) www.bmj.sk.


Assuntos
Síndrome do Túnel Carpal/diagnóstico por imagem , Articulação do Punho/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Ultrassonografia
8.
Cas Lek Cesk ; 147(7): 355-9, 2008.
Artigo em Tcheco | MEDLINE | ID: mdl-18678093

RESUMO

Food allergy is an immune mediated unwanted side effect to food. All types of hypersensitivity can be involved; the most prevalent is IgE mediated one. The diagnosis is based on the history, skin tests with allergens and detection of specific IgE. These procedures are not highly predictive for clinical reactivity to food allergens, true clinical reactivity can be confirmed by allergen challenge. Oral allergy syndrome is represented by mostly subjective symptoms in oral cavity, usually triggered by fruit or vegetable allergens, cross-reacting with pollen allergens. This cross-reactivity is based on protein homology and immunologic similarity. To confirm the diagnosis of food allergy, the ,,golden standard" is the double blind placebo controlled food challenge. The basic features of this test are discussed, particularly in the diagnosis of the oral allergy syndrome. Controlled food challenge is a useful test for patient's diagnosis confirmation, evaluation of other diagnostic tests or evaluation of food allergenicity.


Assuntos
Hipersensibilidade Alimentar/diagnóstico , Doenças da Boca/etiologia , Hipersensibilidade Alimentar/etiologia , Humanos , Testes Imunológicos , Doenças da Boca/diagnóstico
9.
Folia Biol (Praha) ; 53(5): 173-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17976307

RESUMO

In this work, we studied the association of the E23K polymorphism of the Kir6.2 ATP-sensitive potassium channels in 212 Czech patients with diabetes mellitus who were diagnosed after the age of 35. Patients were classified into T1DM, LADA and T2DM groups based on C-peptide and GADA levels. Carriers of the predisposing Kir6.2 E23K K allele showed no increased risk of either type of diabetes mellitus development. On the other hand, we found a correlation between E23K SNP of the KCNJ11 gene and C-peptide levels, which may be considered a measure of pancreatic beta-cell activity, although this correlation was not statistically significant. In conclusion, we failed to confirm the Kir6.2 E23K as a genetic marker for T1DM, LADA and T2DM in the Central Bohemian population of the Czech Republic.


Assuntos
Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Ácido Glutâmico/genética , Lisina/genética , Polimorfismo de Nucleotídeo Único/genética , Canais de Potássio Corretores do Fluxo de Internalização/genética , Adulto , Idade de Início , Peptídeo C , Estudos de Casos e Controles , República Tcheca/epidemiologia , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
10.
Neurogastroenterol Motil ; 18(6): 472-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16700727

RESUMO

Digestive motility was studied in the rat using a miniaturized version of the Magnet Tracking system which monitored the progression of a small magnetic pill through the entire digestive tract. The dynamics of movement was followed and three-dimensional (3-D) images of digestive tract were generated. After a retention period in the stomach and rapid passage through duodenum, the magnet progressed along the small intestine with gradually decreasing speed and longer stationary periods. It remained in the caecum for variable intervals. In the colon, periods of progress alternated with long quiescent periods. Gastric activity oscillated at 5-6 min(-1). In the small intestine, two frequency domains coexisted, showing independent modulations and proximo-distal gradients (40 to >32 and 28 to >20 min(-1)). Caecal oscillations were of 1.5 min(-1). The data allowed the magnet location and calculation of gastric and small intestinal transit times (58 +/- 36 and 83 +/- 14 min respectively), both significantly prolonged by oleate administration (243 +/- 130 and 170 +/- 45 min respectively). Magnet Tracking is a non-invasive tool to study the in vivo spatial and temporal organization of gastrointestinal motility in the rat.


Assuntos
Motilidade Gastrointestinal/fisiologia , Trato Gastrointestinal/anatomia & histologia , Magnetismo/instrumentação , Miniaturização , Animais , Feminino , Trato Gastrointestinal/fisiologia , Imobilização , Masculino , Ratos , Ratos Long-Evans
11.
J Clin Oncol ; 13(11): 2752-6, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7595734

RESUMO

PURPOSE: From December 1983 through February 1992, a prospective study designed to determine the clinical course of patients with ovarian tumors of low malignant potential (LMP) was conducted by the Gynecologic Oncology Group (GOG). MATERIALS AND METHODS: This protocol was developed to evaluate the following (1) the biologic behavior of ovarian LMP tumors, (2) the effectiveness of melphalan chemotherapy in patients with clinically detectable residual disease after surgical staging and in patients whose tumors progress or recur after surgical therapy, and (3) the response rate to cisplatin in those who failed to respond to melphalan therapy. The study group consisted of 146 assessable patients with stage I serous LMP tumors. All of these women had the affected ovary (or ovaries) removed, and a complete staging operation was performed in each case. While 123 patients had a total abdominal hysterectomy (TAH) and bilateral salpingo-oophorectomy (BSO), 21 retained the uterus and one normal-appearing ovary and fallopian tube. No adjuvant chemotherapy or radiation therapy was administered to any patients in the stage I study group. RESULTS: The median follow-up time was 42.4 months (range, 1.6 to 108). Thus far, no patient with a stage I ovarian serous LMP tumor has developed recurrent disease. CONCLUSION: Stage I ovarian serous LMP tumors rarely, if ever, recur. Limited resection, after meticulous surgical exploration, is adequate therapy for women of reproductive age.


Assuntos
Cistadenocarcinoma Seroso/patologia , Neoplasias Ovarianas/patologia , Adulto , Idoso , Cisplatino/uso terapêutico , Terapia Combinada , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/cirurgia , Feminino , Seguimentos , Humanos , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/cirurgia , Estudos Prospectivos , Estados Unidos
12.
J Clin Oncol ; 18(1): 106-15, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10623700

RESUMO

PURPOSE: To assess progression-free survival (PFS) and overall survival (OS) in patients with suboptimally debulked epithelial ovarian cancer receiving cisplatin (100 mg/m(2)) or 24-hour infusion paclitaxel (200 mg/m(2)) or the combination of paclitaxel (135 mg/m(2)) followed by cisplatin (75 mg/m(2)). PATIENTS AND METHODS: After stratification for disease measurability, patients were randomized to receive six cycles of one of the treatments every 3 weeks. If measurable, complete response (CR) or partial response (PR) was determined. RESULTS: Six hundred fourteen of 648 patients who entered onto the trial were eligible. Monotherapies were discontinued more frequently (cisplatin because of toxicity or patient refusal [17%], and paclitaxel because of progression [20%]) compared with the combination therapy (7% and 6%, respectively). Neutropenia, fever, and alopecia were more severe with paclitaxel-containing regimens; whereas anemia, thrombocytopenia, neurotoxicity, nephrotoxicity, and gastrointestinal toxicity were more severe with cisplatin-containing regimens. The CR/PR rates on paclitaxel monotherapy were significantly lower compared with the cisplatin regimens (42% v 67%, respectively; P <.001). The relative hazard (RH) of first progression or death was significantly greater among those randomized to paclitaxel (RH = 1.41; 95% confidence interval [CI], 1.15 to 1.73; P <.001) when compared with cisplatin; however, RH did not differ significantly between the two cisplatin regimens (RH = 1.06; 95% CI, 0.895 to 1.30). Relative to cisplatin, the death rate on paclitaxel was 15% greater (RH = 1.15; 95% CI, 0. 929 to 1.42), and the death rate on the combination treatment was 1% less (RH = 0.99; 95% CI, 0.795 to 1.23). These differences among treatment groups were not statistically significant (P =.31). CONCLUSION: Cisplatin alone or in combination yielded superior response rates and PFS relative to paclitaxel. However, OS was similar in all three arms, and the combination therapy had a better toxicity profile. Therefore, the combination of cisplatin and paclitaxel remains the preferred initial treatment option.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/uso terapêutico , Adulto , Idoso , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Paclitaxel/administração & dosagem , Modelos de Riscos Proporcionais , Estatísticas não Paramétricas , Taxa de Sobrevida , Fatores de Tempo , Estados Unidos/epidemiologia
13.
J Gen Physiol ; 106(2): 149-74, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8537814

RESUMO

A Ca(2+)-blockable monovalent cation channel is present in the apical membrane of the ectoderm of the gastrulating chick embryo. We used the patch clamp technique to study several single-channel permeation properties of this channel. In symmetrical conditions without Ca2+, the Na+ current carried by the channel rectifies inwardly. The channel has an apparent dissociation constant for extracellular Na+ of 115 mM at 0 mV and a low density of negative surface charge (-0.03 e/nm2) at its extracellular entrance. The minimal pore diameter is approximately 5.8 A, as calculated from the relative permeabilities of 10 small organic cations. Extracellular application of six large organic cations decreased the inward Na+ current in a voltage-dependent manner, which strongly suggests an intrachannel block. The presence of at least two ion binding sites inside the pore is inferred from the Na+ dependence of the block by the organic cations. This hypothesis is strengthened by the fact that the extracellular Ca2+ block is also modified by the Na+ concentration. In particular, the rise of the unblocking rate with increased Na+ concentrations clearly suggests the presence of an interaction between Ca2+ and Na+ inside the channel. A low probability of double occupancy at physiological ionic conditions is implied from the absence of an anomalous mole fraction effect with mixtures of extracellular Li+ and K+. Finally, the absence of inward current at very strong hyperpolarizations and in the presence of 10 mM extracellular Ca2+ demonstrates the absence of significant Ca2+ current through this channel. It is argued that this embryonic epithelial Ca(2+)-blockable monovalent cation channel is related to both L-type Ca2+ channel and cyclic nucleotide-gated channels.


Assuntos
Canais de Cálcio/metabolismo , Cálcio/metabolismo , Permeabilidade da Membrana Celular/fisiologia , Ectoderma/metabolismo , Ativação do Canal Iônico/fisiologia , Animais , Embrião de Galinha , Potenciais da Membrana , Técnicas de Patch-Clamp , Potássio/metabolismo , Sódio/metabolismo
14.
Neurogastroenterol Motil ; 17(1): 148-54, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15670274

RESUMO

A new minimally invasive technique allowing for anatomical mapping and motility studies along the entire human digestive system is presented. The technique is based on continuous tracking of a small magnet progressing through the digestive tract. The coordinates of the magnet are calculated from signals recorded by 16 magnetic field sensors located over the abdomen. The magnet position, orientation and trajectory are displayed in real time. Ten young healthy volunteers were followed during 34 h. The technique was well tolerated and no complication was encountered. The information obtained was 3-D configuration of the digestive tract and dynamics of the magnet displacement (velocity, transit time, length estimation, rhythms). In the same individual, repeated examination gave very reproducible results. The anatomical and physiological information obtained corresponded well to data from current methods and imaging. This simple, minimally invasive technique permits examination of the entire digestive tract and is suitable for both research and clinical studies. In combination with other methods, it may represent a useful tool for studies of GI motility with respect to normal and pathological conditions.


Assuntos
Diagnóstico por Imagem/métodos , Motilidade Gastrointestinal , Magnetismo , Adulto , Algoritmos , Calibragem , Interpretação Estatística de Dados , Feminino , Humanos , Intestinos/anatomia & histologia , Masculino , Estômago/anatomia & histologia
15.
Bratisl Lek Listy ; 106(10): 293-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16541607

RESUMO

Peripheral neuropathy was induced by the long-term administration of organo-phosphorus compounds (phtalimid/phosmet) in quails (Coturnix coturnix japponica). After 4 weeks, the first symptoms of organophosphorus (OPC) poisoning (apathy, diarrhea) were present. During the second month of a daily administration of the toxic substance using the probe, an apparent clinical autonomic and peripheral neuropathy with ataxia had developed. Toxic disturbance of the nervous system was confirmed by the examination of spinal and cortical somatosensory evoked potentials (SEP) after tibial nerve stimulation. The prolongation of the peripheral conduction time (wave P6 and N9 represent the response from the ischiadic nerve and the entry of the stimulus to spinal cord, respectively) confirmed a peripheral nerve lesion. We suggest that these clinical and electrophysiological changes, displayed by the disturbed nervous system, are caused by either slowing or stoppage of the axonal flow, transport of proteins and other substances, as well as by axon demyelination (Tab. 1, Fig. 1, Ref. 22).


Assuntos
Inseticidas/toxicidade , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Fosmet/toxicidade , Animais , Doença Crônica , Coturnix , Potenciais Somatossensoriais Evocados/efeitos dos fármacos
16.
Cas Lek Cesk ; 144(7): 445-50; discussion 451-4, 2005.
Artigo em Sk | MEDLINE | ID: mdl-16161536

RESUMO

Mild brain injury is one of the most common neurological a neurotraumatological diagnoses. The pathophysiological basis of mild brain injury is frequently a diffuse axonal damage of variable degree. In the acute phase of mild brain injury we have to identify 1% of patients who will undergo neurosurgery because of vital need. The analysis of patient's personal history, screening of risk factors, neuropsychological testing and imaging methods (CT, MRI) are irreplaceable in the diagnostic process of mild brain injury. Though the mild brain injury is currently considered as an irrelevant traumatic event, approximately 10% of patients develop the so-called post-concussion syndrome.


Assuntos
Concussão Encefálica , Concussão Encefálica/diagnóstico , Concussão Encefálica/fisiopatologia , Concussão Encefálica/terapia , Lesão Axonal Difusa/diagnóstico , Lesão Axonal Difusa/etiologia , Lesão Axonal Difusa/fisiopatologia , Humanos
17.
Semin Oncol ; 24(1 Suppl 2): S2-13-S2-16, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9045329

RESUMO

This prospective study compared the combination of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) and cisplatin with the standard therapy of cyclophosphamide/cisplatin in women with suboptimal stage III and stage IV ovarian cancer. Of the initial 410 women who presented with advanced disease and greater than 1 cm residual masses after initial surgery, 386 met all eligibility criteria and were randomly assigned to receive a regimen of cisplatin 75 mg/m2 and cyclophosphamide 750 mg/m2 or cisplatin 75 mg/m2 and paclitaxel 135 mg/m2 delivered over 24 hours. Dosage reductions were permitted in the event of significant toxicity. Among 216 patients with measurable disease, responses were reported in 73% of those receiving cisplatin/paclitaxel and in 60% of those receiving cisplatin/cyclophosphamide. Median progression-free survival was significantly longer (P < .001) in the group treated with cisplatin/paclitaxel, compared with those receiving cisplatin/cyclophosphamide (17.9 v 12.9 months, respectively).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Estudos Prospectivos
18.
Semin Oncol ; 23(5 Suppl 12): 40-7, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8941409

RESUMO

Administration of an alkylating agent plus a platinum coordination complex is standard therapy for advanced epithelial ovarian cancer in the United States. The most commonly used combination is cyclophosphamide/ cisplatin; however, the benefit of this combination in overall survival has not been compelling. We report a prospective comparison of this regimen versus a combination of cisplatin with paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ), a new and well-tolerated agent with documented activity in cisplatin-refractory ovarian cancer. Three hundred eighty-six patients with advanced ovarian cancer and greater than 1 cm residual masses following initial surgery were randomly assigned to receive a regimen of cisplatin (75 mg/m2) and cyclophosphamide (750 mg/m2), or cisplatin (75 mg/m2) and paclitaxel (135 mg/m2), delivered over 24 hours. Dose reductions in cyclophosphamide or paclitaxel were permitted for significant toxicity. In 216 patients with measurable disease, responses were reported in 73% of those randomized to the cisplatin/paclitaxel arm and in 60% randomized to the cisplatin/cyclophosphamide arm. Progression-free survival was significantly longer (P < .001) with cisplatin/paclitaxel (median, 12.9 v 17.9 months). Overall survival was also significantly longer (P < .001) with cisplatin/paclitaxel (median, 37.5 v 24.4 months). Incorporating paclitaxel into first-line therapy for patients with suboptimally debulked stage III and stage IV ovarian cancer can increase the duration of the progression-free interval and extend overall survival while maintaining an acceptable toxicity profile.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Estudos Prospectivos , Terapia de Salvação
19.
Invest Ophthalmol Vis Sci ; 41(9): 2600-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10937572

RESUMO

PURPOSE: To identify possible neuronal pathways leading to herpetic ocular disease after primary oral infection in mice. METHODS: The SC16 strain of herpes simplex virus (HSV)-1 (10(6) plaque-forming units) was injected into the mucocutaneous border of the left upper lip. Animals were killed 2 to 10 days postinoculation (DPI). Spread of the virus in neural structures was studied by immunochemistry. RESULTS: HSV1 first replicated at the site of inoculation and then at the superior cervical ganglion (at 2 DPI). The trigeminal ganglion and the facial nerve fibers were infected by 4 DPI. Infection of the ciliary body and iris occurred at 6 DPI, together with several brain stem nuclei belonging to the autonomic or sensory pathways. Between 8 and 10 DPI, the neural infection gradually cleared up, except for the ipsilateral sympathetic ganglion, and ipsilateral keratitis appeared in some animals. CONCLUSIONS: The pattern of viral dissemination in this mouse model suggests that infection of iris and ciliary body results from transfer of virus in the superior cervical ganglion from sympathetic neurons innervating the lip to neighboring neurons innervating the anterior uvea. Later, zosteriform spread of virus from the trigeminal system may have contributed to the clinical and histologic findings.


Assuntos
Infecções Oculares Virais/virologia , Herpes Simples/virologia , Herpesvirus Humano 1/fisiologia , Mucosa Bucal/inervação , Vias Neurais/virologia , Gânglio Cervical Superior/virologia , Uveíte Anterior/virologia , Replicação Viral/fisiologia , Animais , Tronco Encefálico/virologia , Corpo Ciliar/inervação , Corpo Ciliar/virologia , Cricetinae , Infecções Oculares Virais/patologia , Nervo Facial/virologia , Feminino , Herpes Simples/patologia , Herpesvirus Humano 1/isolamento & purificação , Iris/inervação , Iris/virologia , Camundongos , Camundongos Endogâmicos BALB C , Mucosa Bucal/patologia , Mucosa Bucal/virologia , Fatores de Tempo , Gânglio Trigeminal/virologia , Uveíte Anterior/patologia
20.
Chest ; 110(1): 189-97, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8681627

RESUMO

Various pulmonary artery preparations in vitro demonstrate sustained endothelium-dependent contractions upon hypoxia. To determine whether endothelin-1 could mediate this phenomenon, we examined the effect of bosentan, a new antagonist of both the ETA and ETB subtypes of the endothelin receptor. Small (300 pm) pulmonary arteries from rats were mounted on a myograph, precontracted with prostaglandin F2 alpha and exposed to hypoxia (PO2, 10 to 15 mm Hg, measured on-line) for 45 min. Endothelium-intact control rings exhibited a biphasic response, with a transient initial vasoconstriction (phase 1) followed by a second slowly developing sustained contraction (phase 2). Expressed in percent of the maximal response to 80 mmol/L KCl, the amplitudes of phase 1 (peak tension) and 2 (tension after 45 min of hypoxia) averaged 37 +/- 12% and 17 +/- 14%, respectively (n = 11). In endothelium-denuded rings, phase 1 persisted while the amplitude of phase 2 was reduced to 2 +/- 12% (p < 0.05, n = 8), showing the endothelium dependence of this contraction. Neither phase was significantly decreased in rings treated with 10(-5) mmol/L bosentan (38 +/- 15% and 17 +/- 12%, respectively, n = 6). The PO2 threshold for onset of hypoxic contraction was not significantly different among these three groups and averaged 32 +/- 24 mm Hg. In a separate experiment, we assessed the inhibitory effect of 10(-5) mol/L bosentan on the response to 10(-8) mol/L endothelin-I. Rings treated for 45 min with 10(-8) mol/L endothelin-1 alone exhibited a maximal contraction of 75 +/- 27% (n = 6). This was reduced to 4 +/- 17% (p < 0.01, n = 6) in rings treated with both 10(-8) mol/L endothelin-1 and 10(-5) mol/L bosentan. We conclude that complete blockade of all endothelin receptor subtypes has no effect on either endothelium-dependent or -independent hypoxic contractions in this preparation. This suggests that endothelial factors other than endothelin-I mediate the acute hypoxic contractions of small pulmonary arteries in the rat.


Assuntos
Endotelinas/fisiologia , Endotélio Vascular/fisiologia , Hipóxia/fisiopatologia , Artéria Pulmonar/fisiopatologia , Vasoconstrição/fisiologia , Animais , Bosentana , Antagonistas dos Receptores de Endotelina , Endotelinas/farmacologia , Técnicas In Vitro , Masculino , Artéria Pulmonar/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Sulfonamidas/farmacologia , Vasoconstrição/efeitos dos fármacos
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