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1.
A case of sudden death due to massive myocardial sarcoidosis is presented. Cardiac sarcoidosis is discussed. Since the deceased was a New York City police officer with death benefit entitlements under the Heart Bill, the implications of the medicolegal autopsy are emphasized.  相似文献   

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Heme oxygenase (HO) is the rate-limiting enzyme in the catabolism of heme to bilirubin. Cobalt chloride (CoCl2) and many other agents that generate oxidant stresses induce the HO-1 isoform. Furthermore, HO-1 has been shown to protect against oxidant stress in vitro and in vivo by mechanisms involving increased ferritin synthesis. However, little is known about the inducibility of hepatic HO-1 during the very early postnatal period, and whether HO-1 induction is associated with increased ferritin synthesis in neonates. Therefore, we studied hepatic HO-1 mRNA, HO-1 protein concentration, total HO activity, and ferritin protein levels in neonatal rats. Neonatal rats 0-5 d of age were injected with 250 mumol/kg body weight of CoCl2. 6H2O in saline or with an equal volume of saline in age-matched controls. Liver samples were collected 4 h after injection for HO-1 mRNA analysis and 20 h after injection for analysis of HO-1 protein concentration, total HO activity, and ferritin protein levels. In CoCl2-treated rats, hepatic HO-1 mRNA was 3-10 times the levels in control rats (p < 0.05), HO-1 protein concentration was 2-5 times the levels in control rats (p < 0.05), and total HO activity was higher by 20-80% than in control rats (p < 0.05). There were no differences in hepatic ferritin protein levels between CoCl2-treated neonatal rats and controls; however, in CoCl2-treated adult rats, hepatic ferritin protein levels were 1.6 times the levels in controls (p < 0.05). Thus, neonatal rats can up-regulate hepatic HO-1 mRNA, HO-1 protein concentration, and total HO activity in response to CoCl2; however, no upregulation of hepatic ferritin protein levels was observed in neonatal rats after CoCl2 administration or subsequent HO-1 induction. We speculate that neonatal rats induce hepatic HO-1 and up-regulate ferritin by different mechanisms than do adult rats.  相似文献   

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Maternal samples were assessed from 96 women enrolled in Pediatric AIDS Clinical Trials Group protocol 076 to determine the prevalence of human immunodeficiency virus type 1 (HIV-1) genotypic zidovudine resistance at entry, if zidovudine resistance developed on study, and the role of zidovudine resistance in vertical transmission of HIV-1 despite zidovudine therapy. Low and high levels of genotypic resistance were assessed by differential hybridization, oligoligation, or direct sequencing of plasma HIV-1 RNA for codons K70R and T215Y/F. None of the women had high-level genotypic resistance to zidovudine at study entry or delivery. For low-level zidovudine resistance, the 95% confidence intervals were 0.3%-6.8% for baseline prevalence and 0.3%-14% for delivery incidence. Low-level zidovudine resistance, adjusted for plasma viral RNA level at delivery, was not strongly associated with an increase in vertical transmission risk (odds ratio, 4.8; 95% confidence interval, 0.2-131; P = .35).  相似文献   

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A cohort of 79 homosexual men with documented dates of human immunodeficiency virus type 1 (HIV-1) seroconversion and baseline CD4 cell counts of > or = 500/microL were followed for up to 11.5 years. HIV-1 RNA was measured from stored sera obtained a median of 7 months after the estimated seroconversion date. AIDS progression and mortality among the men were studied, stratified by median baseline levels of HIV-1 RNA. AIDS progression rates at 11.5 years were 69% and 34%, respectively, among those with higher versus lower than median baseline virus loads (> or = 3040 copies/mL; P = .002), and mortality rates were 61% and 27%, respectively (P = .003). Survival curves continued to diverge throughout the 11.5 years, suggesting that the future clinical course of HIV-1 infection may already be determined at the earliest phases of disease. Initiation of definitive treatment very early in HIV-1 infection may be essential.  相似文献   

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Nuclisens HIV-1 QT is a new version of the NASBA HIV-1 QT assay for quantitation of human immunodeficiency virus type 1 (HIV-1) RNA in plasma. The specificity of this assay was 100% in one laboratory and 99%-with nonrepeatability of the initial false positive-in another. The test was linear between 2.0 and 6.0 log RNA copies per ml. According to the input HIV-1 RNA concentration, accuracy varied from -0.11 to +0.10 log RNA copy per ml and precision varied from 0.66 to 0.14 log RNA copy per ml. Reproducibility decreased when the HIV-1 RNA level was near the lower limit of quantitation of the test. HIV-1 RNA could be quantitated by Nuclisens HIV-1 QT in 36% (laboratory 1) and 24% (laboratory 2) of clinical samples with HIV-1 RNA levels lower than the lower limit of quantitation by NASBA HIV-1 QT. Nuclisens HIV-1 QT was not suitable for measurement of RNA from clade G and group O HIV-1 strains.  相似文献   

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Viruses, including the Human Immunodeficiency Virus (HIV), have evolved multiple strategies to overcome host immune defenses, allowing them to persist in the host. Molecular and cellular approaches were simultaneously used to provide sensitive and unbiased delineation of the diversity and dynamics of the immune response, and to study the relative compartimentalization of HIV-specific CTL clones in patients undergoing primary HIV infection. This approach revealed that some HIV-specific CTL clones can be deleted in presence of high levels of antigen, a phenomenon analogous to high-dose tolerance or clonal exhaustion described in murine models of persistent viral infections. Also, HIV-specific CTL clones were found to accumulate preferentially in peripheral blood as compared to lymph nodes, even though the large majority of viral replication during primary HIV infection takes place within lymph nodes. These two mechanisms may decrease the effectiveness of the host cell-mediated immune responses, and favor the establishment of virus persistence during primary HIV infection.  相似文献   

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Progressive multifocal leukoencephalopathy (PML) is a demyelinating disorder of the CNS that usually causes hemiparesis or hemianopsia. Dementia occurs in combination with other neurologic abnormalities. We report a human immunodeficiency virus type 1 (HIV)-infected man whose only manifestation of proven PML was dementia that was clinically indistinguishable from HIV-associated dementia.  相似文献   

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We have developed small-volume (50 or 250 microl)-format branched-DNA assays for human immunodeficiency virus type 1 (HIV-1) RNA for use with specimens in which the volume is limited and/or a high viral load is anticipated. These formats exhibited good correlation with the standard 1-ml format; high specificity, reproducibility, and linearity; and no significant difference in the quantification of HIV-1 subtypes.  相似文献   

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BACKGROUND: Adults infected by HIV have increased susceptibility to Mycobacterium tuberculosis and progress more rapidly to disease. HIV and tuberculosis (TB) coinfection in children has been reported but often lacks bacterial confirmation. We report on the clinical picture, special investigations, clinical course and outcome of 14 children with HIV infection and culture-confirmed TB from a developing country. METHODS: The clinical records of all children, from 1992 to 1997, with HIV infection and culture-proved TB were reviewed. RESULTS: Fourteen (10.4%) of 135 children with vertically transmitted HIV infection, 93% <2 years of age, fit the criteria. Nonresolving pneumonia (4) and otorrhoea (6) were common complaints. A Mantoux test was positive (> or =15 mm) in 6 of 11 children. Extrapulmonary TB was present in 5 cases. Ear swabs were the source of M. tuberculosis culture in 3. Chest radiographs were abnormal in all with hilar and paratracheal lymphadenopathy present in 7. A source case with pulmonary TB was identified for 10. Susceptibility tests were done on 9 strains of which 1 was drug-resistant. Four children were culture-positive 4 to 10 months after initiation of TB treatment. Mortality was 21% and 3 were lost to follow-up. CONCLUSIONS: In HIV-infected children the Mantoux skin test remains useful and culture specimens should be obtained from all sources. Response to treatment is unpredictable, and for this reason repeated cultures should be taken during treatment and a 9-month course of treatment considered.  相似文献   

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One hope to maintain the benefits of antiviral therapy against the human immunodeficiency virus type 1 (HIV-1), despite the development of resistance, is the possibility that resistant variants will show decreased viral fitness. To study this possibility, HIV-1 variants showing high-level resistance (up to 1,500-fold) to the substrate analog protease inhibitors BILA 1906 BS and BILA 2185 BS have been characterized. Active-site mutations V32I and I84V/A were consistently observed in the protease of highly resistant viruses, along with up to six other mutations. In vitro studies with recombinant mutant proteases demonstrated that these mutations resulted in up to 10(4)-fold increases in the Ki values toward BILA 1906 BS and BILA 2185 BS and a concomitant 2,200-fold decrease in catalytic efficiency of the enzymes toward a synthetic substrate. When introduced into viral molecular clones, the protease mutations impaired polyprotein processing, consistent with a decrease in enzyme activity in virions. Despite these observations, however, most mutations had little effect on viral replication except when the active-site mutations V32I and I84V/A were coexpressed in the protease. The latter combinations not only conferred a significant growth reduction of viral clones on peripheral blood mononuclear cells but also caused the complete disappearance of mutated clones when cocultured with wild-type virus on T-cell lines. Furthermore, the double nucleotide mutation I84A rapidly reverted to I84V upon drug removal, confirming its impact on viral fitness. Therefore, high-level resistance to protease inhibitors can be associated with impaired viral fitness, suggesting that antiviral therapies with such inhibitors may maintain some clinical benefits.  相似文献   

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About one-third of vertically HIV-1 infected infants develop AIDS within the first months of life; the remainder show slower disease progression. We investigated the relationship between the pattern of HIV-1 replication early in life and disease outcome in eleven infected infants sequentially studied from birth. Viral load in cells and plasma was measured by highly sensitive competitive PCR-based methods. Although all infants showed an increase in the indices of viral replication within their first weeks of life, three distinct patterns emerged: (a) a rapid increase in plasma viral RNA and cell-associated proviral DNA during the first 4-6 wk, reaching high steady state levels (> 1,000 HIV-1 copies/10(5) PBMC and > 1,000,000 RNA copies/ml plasma) within 2-3 mo of age; (b) a similar initial rapid increase in viral load, followed by a 2.5-50-fold decline in viral levels; (c) a significantly lower (> 10-fold) viral increase during the first 4-6 wk of age. All infants displaying the first pattern developed early AIDS, while infants with slower clinical progression exhibited the second or third pattern. These findings demonstrate that the pattern of viral replication and clearance in the first 2-3 mo of life is strictly correlated with, and predictive of disease evolution in vertically infected infants.  相似文献   

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PURPOSE: The objective of the study was to investigate specificity and sensitivity of bladder wall thickness in the diagnosis of bladder outlet obstruction. MATERIALS AND METHODS: The study included 174 patients referred to our prostate centers for lower urinary tract symptoms. Free uroflowmetry and pressure-flow studies were performed in duplicate as part of the diagnostic evaluation. After the 2 voiding studies were done the bladder was filled to 150 ml. and wall thickness was measured via suprapubic ultrasound. Bladder outlet obstruction was diagnosed and graded according to the Abrams-Griffiths and Sch?fer nomogram as well as to the group specific urethral resistance algorithm. RESULTS: A significant correlation (r > 0.6, p < or = 0.007) was found between bladder wall thickness and all parameters of the pressure-flow study. A bladder wall thickness of 5 mm. appeared to be the best cutoff point to diagnose bladder outlet obstruction, since 63.3% of patients with bladder wall thickness less than 5 mm. were unobstructed while 87.5% of those with a bladder wall thickness 5 mm. or greater were obstructed. Bladder wall thickness out performed uroflowmetry in terms of specificity and sensitivity in the diagnosis of outlet obstruction as demonstrated by an area under curve value of 0.860 versus 0.688 in the receiver operator characteristics analysis. CONCLUSIONS: Measurement of bladder wall thickness appears to be a useful predictor of outlet obstruction with a diagnostic value exceeding free uroflowmetry although it does not represent a substitution to invasive urodynamics. These data support the hypothesis that the relationships between morphology and function are of clinical importance.  相似文献   

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We have used the yeast three-hybrid system (D. J. SenGupta, B. Zhang, B. Kraemer, P. Pochart, S. Fields, and M. Wickens, Proc. Natl. Acad. Sci. USA 93:8496-8501, 1996) to study binding of the human immunodeficiency virus type 1 (HIV-1) Gag protein to the HIV-1 RNA encapsidation signal (HIVPsi). Interaction of these elements results in the activation of a reporter gene in the yeast Saccharomyces cerevisiae. Using this system, we have shown that the HIV-1 Gag protein binds specifically to a 139-nucleotide fragment of the HIVPsi signal containing four stem-loop structures. Mutations in either the Gag protein or the encapsidation signal that have been shown previously to impair this interaction reduced the activation of the reporter gene. Interestingly, the nucleocapsid portion of Gag retained the RNA binding activity but lost its specificity compared to the full-length Gag. These results demonstrate the utility of this system and suggest that a variety of genetic analyses could be performed to study Gag-encapsidation signal interactions.  相似文献   

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