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971.
We describe a case of acute myocarditis subsequent to varicella virus infection. We comment on the rarity of the clinical entity together with the nonspecificity of the routine diagnostic technique (EKG, X-ray, echocardiography study, routine laboratory, etc.) linked with the excellent gain of antibodies cardiac gammagraphy joined with viral serology, after the primary suspicion factor prior to the presence of skin lesions, fever and thoracic pain.  相似文献   
972.
TCR- and IgG-binding Fc receptors (Fc gamma R) mediate a variety of critical biologic activities including cytolysis via the structurally related zeta- and gamma-chains. In previous studies, we have described chimeric immune receptors (CIR) in which the ligand-binding domain of a heterologous receptor or Ab is fused directly to the cytoplasmic domain of the TCR zeta-chain. Such zeta-CIRs efficiently trigger cytotoxic function of both T and NK cells in a target-specific manner. In this report, we compared the ability of both zeta- and gamma-CIRs to activate the cytolytic function of two distinct classes of Fc gamma R-bearing effectors, NK cells and neutrophils. Mature neutrophils expressing zeta- and gamma-CIR were generated in vivo from murine hemopoietic stem cells following transplantation of syngeneic mice with retrovirally transduced bone marrow or in vitro from transduced human CD34+ progenitors following differentiation. Both zeta- and gamma-based CIRs were capable of activating target-specific cytolysis by both NK cells and neutrophils, although the zeta-CIR was consistently more efficient. The experimental approach described is a powerful one with which to study the role of nonlymphoid effector cells in the host immune system and permits the rational design of immunotherapeutic strategies that rely on harnessing multiple immune cell functions via CIR-modified hemopoietic stem cells or progenitors.  相似文献   
973.
BACKGROUND/AIMS: There is growing interest worldwide in primary liver cancer. The aim of this study was to describe the incidence of this cancer over a 20-year period in a well-defined French population. METHODS: Time trends by 4-year period were studied by sex, age group, place of residence, histological type and associated cirrhosis. Trends were also analysed using the age-period-cohort model. RESULTS: Primary liver cancer incidence in men increased from 7.5/100000 for the period 1976-79 to 10.2/100000 for the period 1992-95. The mean annual variation was +2.2%, (p<0.05). The increase in incidence was seen mainly in the 55-64 and 65-74 age groups and concerned hepatocellular carcinomas. In men, the increase in incidence rates with time was observed mainly in rural areas, whereas incidence rates in urban areas remained stable. The rise in incidence was due mostly to an increase in primary liver cancer with cirrhosis, in relation to a progressive increase in post-hepatitic cirrhosis and a recent increase in alcoholic cirrhosis. The estimated cumulative risk for the life span 30-74 years increased from 0.8% for the 1904-1908 cohort to 2.1% for the 1934-1938 cohort. There was no significant trend in female rates. CONCLUSIONS: In France, incidence rates for primary liver cancer are increasing in men, whilst they are remaining stable in women. Our data confirm the primary importance of alcohol in the aetiology of this cancer. Further studies are necessary to unravel the respective roles of alcohol and hepatitis C virus in the increasing incidence of primary liver cancer.  相似文献   
974.
During follicular development the proliferative and differentiated state of the epithelioid granulosa cells changes, and the movement of fluid across the follicular basal lamina enables the formation of an antrum. Type IV collagen is an important component of many basal laminae. Each molecule is composed of three alpha chains; however, six different type IV collagen chains have been identified. It is not known which of these chains are present in the follicular basal lamina and whether the type IV collagen composition of the basal lamina changes during follicular development. Therefore, we immunolocalized each of the six chains in bovine ovaries using antibodies directed to the nonconserved non-collagenous (NC) domains. Additionally, dissected follicles were digested with collagenase to release the NC domains, and the NC1 domains were then detected by standard Western immunoblot methods. The follicular basal lamina of almost all primordial and preantral follicles was positive for all type IV collagen alpha chains. Colocalization of type IV collagen and factor VIII-related antigen allowed for discrimination between the follicular and endothelial basal laminae. Type IV collagen alpha1, alpha2, alpha3, alpha4, and alpha5 chains were present within the follicular basal lamina of only a proportion of antral follicles (17 of 22, 20 of 21, 15 of 18, 14 of 28, and 12 of 23, respectively), and staining was less intense than in the preantral follicles. Staining for the alpha1 and alpha2 chains was diffusely distributed throughout the theca in regions not associated with recognized basal laminae. The specificity of this immunostaining for alpha1 and alpha2 chains of type IV collagen was confirmed by Western immunoblots. As well as being detected in the basal lamina of approximately half of the antral follicles examined, type IV collagen alpha4 also colocalized with 3beta-hydroxysteroid dehydrogenase-immunopositive cells in the theca interna. Type IV collagen alpha6 was detected in the basal lamina of only one of the 16 antral follicles examined. Thus, the follicular basal lamina changes in composition during follicular development, with immunostaining levels being reduced for all type IV collagen chains and immunoreactivity for type IV collagen alpha6 being lost as follicle size increases. Additionally, immunoreactivity for alpha1 and alpha2 appears in the extracellular matrix of the theca as it develops.  相似文献   
975.
Streptococcus pneumoniae is a common cause of meningitis. Nitric oxide (NO) has been implicated in causing cerebral edema. Modulating NO production in cerebrospinal fluid (CSF) may have a role in the treatment of bacterial meningitis. Experimental S. pneumoniae meningitis was induced in a rabbit model to determine CSF parameters and NO concentrations. An electrochemical probe in the CSF throughout the 7-hour experiment monitored NO concentrations. The animals had S. pneumoniae (10(5)) injected intracisternally and incubated for 1 hour. Cerebrospinal fluid 200-300 microl was obtained by intracisternal puncture at zero, 2, 4, and 7 hours after drug administration to measure glucose, protein, and lactic acid by standard chemical methods. White blood cell count was measured by hemocytometry. Three groups of five animals were used-control (C), ceftriaxone (CTX), and ceftriaxone plus dexamethasone (CTX+D). Ceftriaxone concentrations in CSF were obtained by microdialysis and analyzed by high-performance liquid chromatography. Mean (+/- SEM) CSF white blood cell count was significantly higher at 2 hours in the C group than in the other two groups (C 7307 +/- 1302, CTX 605 +/- 345, CTX+D 730 +/- 43/mm3, p<0.002). Ceftriaxone induced a significant rise in protein at 4 hours compared with the other groups (C 364 +/- 107, CTX 1158 +/- 797, CTX+D 365 +/- 100 mg/dl, p<0.02). Cerebrospinal fluid lactic acid was significantly different at 4 and 7 hours between C and CTX+D groups (4-hr C 8.0 +/- 2.2, CTX+D 2.0 +/- 0.4 mmol/L, p<0.05; 7-hr C 10.2 +/- 2.4, CTX+D 2.8 +/- 0.8 mmol/L, p<0.01). Median NO concentrations were significantly elevated in the control group compared with the other two groups (C 11.7, CTX 6.8, CTX+D 6.5 micro, p<0.02 C vs CTX, p<0.01 C vs CTX+D). Average (+/- SEM) NO concentrations were significantly higher in the C group at 4 hours (18.1 +/- 0.4, CTX 5.8 +/- 1.8 microM, p<0.05; CTX+D 11.5 +/- 4.0 microM, p>0.05), whereas they did not rise significantly until 7 hours in the CTX group (CTX 18.7 +/- 0.7, C 8.9 +/- 0.4 microM, p=0.055; CTX+D 8.1 +/- 2.2 microM, p<0.05). These results indicate that ceftriaxone with or without dexamethasone significantly decreases lactic acid concentrations and white cell penetration into the CSF in an experimental model of S. pneumoniae meningitis. In addition, ceftriaxone induced a significant elevation in CSF protein. Median NO production in the CSF was significantly attenuated by ceftriaxone.  相似文献   
976.
977.
978.
The in vitro effects of Cd, Zn, and Pb on pulmonary, adrenal, and hepatic microsomal enzyme activities in guinea pigs were compared. Cd and Zn produced concentration-dependent (20-200 microM) decreases in benzphetamine demethylase and biphenyl hydroxylase activities in adrenal, liver, and lung. Pb had no significant effect on either enzyme in any of the tissues studied. Adrenal and pulmonary enzymes were more sensitive to the effects of Cd and Zn than were hepatic enzymes. Benzo[a]pyrene hydroxylase and ethoxycoumarin deethylase activities were decreased by Zn, Cd, and Pb in adrenal, liver, and lung microsomes. The inhibitory effect on benzo[a]pyrene and ethoxycoumarin metabolism were far greater than those on benzphetamine or biphenyl metabolism. The relative potencies of the metals as inhibitors of xenobiotic metabolism were Zn greater than Cd greater than Pb. Cd and Zn also inhibited steroid 21-hydroxylase activity in adrenal microsomes, but Pb had no effect on steroid metabolism. In addition, microsomal epoxide hydratase activity in adrenal, liver, and lung was inhibited by Cd but not by Zn or Pb. The results demonstrate that adrenal and pulmonary microsomal enzymes, like those in liver, are inhibited by various metals. Inhibition of mixed-function oxidases by metals in vitro is apparently not related to changes in cytochrome P-450 levels or substrate binding to cytochrome P-450. In addition, the actions of Cd, Zn, and Pb in each tissue are highly dependent on the substrates employed.  相似文献   
979.
A reproducible and sensitive radioimmunoassay for digoxin in either serum, plasma or urine is described. Using 0.5 ml of serum or plasma, the assay sensitivity is 0.05 ng of digoxin/ml. The antiserum and tracer solutions employed are available in a kit sold in the United States. All other reagents were prepared in the laboratory. The assay allows measurement of digoxin in plasma or serum for 96 hours after single 0.5 mg doses of digoxin; this is necessary in human bioavailability studies to accurately estimate the total area under the digoxin concentration, time curve from zero to infinite time. In contrast, with the kit assay, employing 0.2 ml of plasma or serum, it has been reported that the 12 hr serum digoxin levels, after single 0.5 mg doses, are, in most subjects, below the sensitivity limit (about 0.5 ng/ml) of the assay.  相似文献   
980.
The ultrastructural cytopathologic and cytochemical effects of trimethyltin (TMT) neurotoxicity were delineated in hippocampal and pyriform neurons of acutely intoxicated adult rats. TMT produced neuronal necrosis that preferentially involved hippocampal formation pyriform cortex. The first subcellular alterations were multifocal collection of dense-cored vesicles and tubules and membrane-delimited vacuoles in the cytoplasm of the perikaryon and proximal dendrite. Ultrastructural cytochemical examination revealed that the vesicles and tubules had acid phosphatase activity analagous to Golgi-associated endoplasmic reticulum (GERL). Shortly after the appearance of the GERL-like vesicles and tubules, autophagic vacuoles and polymorphic dense bodies accumulated in the neuronal cytoplasm. Some dense bodies appeared to arise from the dense-cored tubules. Neuronal necrosis was characterized by increased electron density of the cytoplasm and large, electron-dense intranuclear masses. Alterations of mitochondria and other organelles were not observed in the early stages of cell injury. No light- or electron-microscopic alterations were found in liver or kidney. Comparable subcellular alterations were observed in adult and neonatal rats chronically intoxicated with TMT. A series of other trialkyl and tricyclic tins and dimethyltin did not produce similar pathologic findings. The GERL-like accumulations are unique in neuronal cytopathology. These findings suggests that GERL and autophagy play an important role in the pathogenesis of TMT-induced neuronal injury.  相似文献   
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