Acute sporadic non-A, non-B, non-C, non-D, non-D, non-E hepatitis

Patients presenting with clinical and laboratory features consistent with a diagnosis of acute non-A, non-B hepatitis were evaluated for evidence of hepatitis C or hepatitis E infection and for evidence of severe or prolonged disease. Antibody to hepatitis C virus (anti-HCV) was detected in 75 of 108 (69%) patients, antibody to hepatitis E virus (anti-HEV) in three patients (3%), and neither antibody in 31 (29%) patients. One patient had both anti-HCV and anti-HEV. HCV RNA was not detected in sera from any of 20 patients with seronegative (non-ABCDE) hepatitis, but in all 10 patients with anti-HCV who were tested by polymerase chain reaction (PCR). Compared with patients with acute hepatitis C, those with non-ABCDE hepatitis had a lower incidence of parenteral risk factors (6% vs. 70%; P < .001), higher peak serum bilirubin levels (45% vs. 5% with peak levels > 15 mg/dL; P < .001), more prolonged jaundice (25% vs. 0% with peak bilirubin >5 weeks after onset; P < .01), more severe prothrombin time abnormalities (26% vs. 0% with >3 second prolongation; P < .001), more severe hypoalbuminemia (39% vs. 9% with albumin <3 g/dL; P < .01), and more frequent major clinical complications (13% vs. 0% with encephalopathy; P < .01; 10% vs. 0% with death or transplant; P = .024). Patients with acute non-ABCDE hepatitis were less likely to develop chronic hepatitis than those with acute hepatitis C (23% vs. 68%; P < .05). Thus, patients with acute non-ABCDE hepatitis are epidemiologically distinct from those with acute hepatitis C and have a significantly more severe acute illness.

Gradual shutdown of virus production resulting in latency is the norm during the chronic phase of human immunodeficiency virus replication and differential rates and mechanisms of shutdown are determined by viral sequences

Most CD4+ lymphocytes in lymph nodes of both asymptomatic HIV-1-infected individuals and AIDS patients are nonproductively or latently infected. It is not clear how these cells come about because infection of resting lymphocytes results in abortive infection and infection of activated lymphocytes results in productive infection. The frequency and mechanisms underlying nonproductive or latent HIV infections of normal CD4+ lymphocytes largely remain unexplored, and because HIV latency has principally been studied in latently infected cell clones of established cell lines, it is not even clear how often this type of infection occurs in cell lines. We demonstrate herein that chronic HIV replication in populations of normal phytohemagglutinin-stimulated peripheral blood CD4(+)-enriched lymphocytes, as well as an established T-cell line (CEM), gradually shuts down in the vast majority of cells. The nonproducing cells in these cultures still harbored HIV provirus, and HIV could be reactivated in CEM cells by treatment with phorbol ester, showing that this was latent infection. Thus, HIV's life cycle should probably be considered as consisting of two phases an acute exponential rise in production of virus progeny which levels at some peak, followed by a gradual decline of progeny production during the chronic phase leading to viral latency. Temporal analyses of the steady-state levels of viral mRNAs in populations of chronically infected CEM cells as virus production declined revealed the two mechanisms of HIV latency which have previously been described in the OM-10.1 and U1 or ACH-2 latently infected cell clones (i.e., apparent overall shutdown of HIV transcription and "blocked early-stage latency" involving enhanced splicing of viral pre-mRNAs) However, which mechanism was employed, as well as the rate of shutdown, depended on the virus strain.

Managed care. Past, present, and future

Managed care is now the driving force of the emerging health care provision systems in the United States. It has 2 well-recognized features: (1) its payers (business and government) seem to be pleased with it and (2) its customers and employees (patients and providers) are concerned with its health care provisions and financial practices.

Generation and analysis of 280,000 human expressed sequence tags

We report the generation of 319,311 single-pass sequencing reactions (known as expressed sequence tags, or ESTs) obtained from the 5' and 3' ends of 194,031 human cDNA clones. Our goal has been to obtain tag sequences from many different genes and to deposit these in the publicly accessible Data Base for Expressed Sequence Tags. Highly efficient automatic screening of the data allows deposition of the annotated sequences without delay. Sequences have been generated from 26 oligo(dT) primed directionally cloned libraries, of which 18 were normalized. The libraries were constructed using mRNA isolated from 17 different tissues representing three developmental states. Comparisons of a subset of our data with nonredundant human mRNA and protein data bases show that the ESTs represent many known sequences and contain many that are novel. Analysis of protein families using Hidden Markov Models confirms this observation and supports the contention that although normalization reduces significantly the relative abundance of redundant cDNA clones, it does not result in the complete removal of members of gene families.

Identification of hepatitis C virus by immunoelectron microscopy

Sequencing of the hepatitis C virus (HCV) has provided a better understanding of the natural history, immunology, and epidemiology of this virus. However, the morphology of HCV has not been definitively characterized. In this study, through a sequence of concentration processes, virus-like particles were isolated from human serum and liver tissue, visualized by transmission electron microscopy and identified as hepatitis C virion by immunoelectron microscopy. Spherical flavi-like virus particles, approximately 70 nm in diameter, were observed in the fraction with 1.04-1.12 g ml-1 sucrose density and bound to immunogold particles with monoclonal antibodies (mAb) against hepatitis C. The nucleocapsid of the particles, which were 50 nm in diameter, appeared to be icosahedral in structure and surrounded by an envelope covered with surface projections. A 'tadpole' form of particles was also observed. The findings indicate that the low buoyant density in sucrose and the morphological features of the hepatitis C virion are consistent with the characteristics of flaviviruses and pestiviruses.

The maize mitochondrial genome: dynamic, yet functional

The organization of the mitochondrial genome of higher plants is complex. It has two striking features: a large size that can vary among plant species; and the ability to undergo homologous recombination that results in variation within species. From cosmid clone mapping studies, the total genetic information of the plant mitochondrial genome can be arranged into a single circular molecule that is referred to as the master chromosome. This circular DNA molecule contains repeated sequences that can generate, via intramolecular recombination, either isomeric forms of the master chromosome or smaller subgenomic circular DNA molecules. The maize mitochondrial genome is the most complex and largest mitochondrial genome for which a physical map is presently available. Its organization varies considerably among the different maize cytotypes. In an attempt to understand the numerous different mitochondrial DNA rearrangements encountered among those cytotypes, we have proposed a general model of genome evolution that can explain a multitude of genomic rearrangements, not only for the maize mitochondrial DNA but also for other higher plant mitochondrial genomes as well.

Antibody to hepatitis C virus second envelope (HCV-E2) glycoprotein: a new marker of HCV infection closely associated with viremia

The second envelope protein (E2) of the hepatitis C virus (HCV) was cloned and expressed in Chinese hamster ovary (CHO) cells. This E2 glycoprotein was purified using ion exchange and lectin chromatography and used to construct an enzyme immunoassay for HCV E2 antibodies. The assay was shown to have good specificity, and detection of E2 antibodies was positively correlated (97.3%) to the presence of HCV RNA in serum and plasma. A high concordance between HCV 2.0 and E2 EIA reactivities was also observed. E2 antibody was the first serological marker to appear in 3/5 HCV seroconversion panels. This work demonstrated that 42.4% of core and 15.4% of NS3 indeterminate specimens also contained antibodies to E2, suggesting that HCV infection had occurred in these individuals. The E2 antibody assay was used to evaluate HCV 2.0 EIA-positive, HCV 3.0 EIA-negative plasma donors with indeterminate reactivity on RIBA HCV 2.0 or MATRIX HCV 1.0. Several HCV 3.0-negative specimens were shown to contain E2 antibodies in addition to an original indeterminate serological marker, primarily core. It is concluded that anti-E2 is a useful marker for determining HCV infection, and that the presence of antibodies to two nonoverlapping viral gene products suggests true HCV exposure. New HCV 3.0 blood screening tests should detect HCV 2.0-positive donors who present with an indeterminate pattern by RIBA or MATRIX and who also carry E2 antibodies.

Optimism in children's judgments of health and environmental risks

Although optimistic bias has been well documented for adults, little is known about how children view their own risks vis-à-vis those of their peers. Two studies of 6th graders examined optimism and the degree of differentiation in perceived risks across diverse health, lifestyle, and environmental problems. The findings revealed perceptions of relative invulnerability and highly differentiated risk assessments. The strongest levels of optimism emerged for controllable and stigmatizing events such as illicit drugs, smoking, and AIDS. The effects of gender, assessment context, and methodological variations were minimal. Discussion focused on the implications for health-promoting interventions with school-age children, the need for developmental information about risk perception processes, and the difficulty of distinguishing realistic from biased optimism.

Loin pain-hematuria syndrome with a distinctive vascular lesion and alternative pathway complement activation

We describe a 48-year-old woman with loin pain-hematuria syndrome. Her renal abnormalities included conspicuous microaneurysmal and glomeruloid (plexiform) angiomatous changes. The deposition of both properdin and the C5b-9 complex, as well as the usual C3, in arterioles argues for complement activation. To our knowledge, neither of these features has been previously described. We speculate about the cause of loin pain-hematuria syndrome and note the uncommonness of this entity in the United States as opposed to Great Britain.

Optimism in children's judgments of health and environmental risks

Although optimistic bias has been well documented for adults, little is known about how children view their own risks vis-à-vis those of their peers. Two studies of 6th graders examined optimism and the degree of differentiation in perceived risks across diverse health, lifestyle, and environmental problems. The findings revealed perceptions of relative invulnerability and highly differentiated risk assessments. The strongest levels of optimism emerged for controllable and stigmatizing events such as illicit drugs, smoking, and AIDS. The effects of gender, assessment context, and methodological variations were minimal. Discussion focused on the implications for health-promoting interventions with school-age children, the need for developmental information about risk perception processes, and the difficulty of distinguishing realistic from biased optimism.

Multiple herpesviruses in saliva of HIV-infected individuals

Oral infections with human herpesviruses cause increased morbidity in patients infected with HIV. In this study, multiple HHVs were often isolated from the saliva of HIV-seropositive dental patients, but their isolation rate did not differ substantially from rates reported for the general population, except for human cytomegalovirus.

Microvascular architecture within the pig kidney cortex

Corrosion casts of the plastic (Mercox Cl-2B) filled pig kidney cortex vasculature were sliced either parallel or perpendicular to the kidney surface. Scanning electron microscopy photographs were taken of the casts. Montages of the photographs were analyzed using a digitizing tablet and microcomputer-based software. For vessels having diameters larger than 0.05 mm, their sizes, numbers per unit area, and branching patterns were studied with respect to the kidney cortex depth. Vascular branching diameters and angles within the cortex compare favorably with those reported for other major vascular systems. The microvascular dimensions and densities were used to predict the average blood flow velocity within the kidney cortex. It is expected that the results will facilitate a better insight into the contribution of flowing blood to the heat transfer process in perfused tissues.

Changes in body composition and bone density after discontinuation of growth hormone therapy in adolescence: an interim report

Growth hormone deficiency (GHD) in adults and children is associated with decreased lean tissue mass (LTM), increased fat mass and reduced bone mineral density (BMD). The changes in BMD and body composition, 6 and 12 months after ceasing GH treatment, were assessed using dual-energy X-ray absorptiometry in eight patients with GHD (age range, 13.8-17.5 years). Seven age-matched normal subjects who had completed growth were assessed at 0 and 12 months. Total body BMD was low at baseline (p < 0.05) in patients with GHD compared with the predicted values based on sex-specific regression equations, with height, weight and age taken into account. Total body, lumbar spine and femoral neck BMD increased in the patients and controls at 12 months. LTM decreased significantly by a mean of 1.37 kg in the patients with GHD at 12 months whereas there was a non-significant increase in LTM in the control group. The percentage of body fat increased in all patients with GHD at 6 and 12 months, from 27.2 +/- 11% (mean +/- SD) at baseline to 32 +/- 9.9% at 12 months (p = 0.009). There was no significant increase in mean percentage body fat in the control group. The ratio of android (trunk):gynoid (legs) fat was calculated using default settings of dual-energy X-ray absorptiometry. The mean android:gynoid fat ratio increased, though non-significantly, in patients with GHD at 12 months, with 6 of 7 showing an increase; no change was observed in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Preadolescents' perceptions of AIDS before and after Earvin Magic Johnson's announcement

Compared sixth graders' AIDS concerns before and after Magic Johnson announced that he tested HIV-positive. Examined perceptions of self/other vulnerability (optimistic bias) using questionnaires (Study A) and interviews (Study B). Also examined AIDS worries mentioned in open-ended interviews (Study C). Studies A and B revealed a substantial degree of optimistic bias. Study C showed that AIDS is a prime concern of school-age students, mentioned under free or context-cued conditions by about 50%. There was little detectable effect of the publicity; the sole before--after difference in three studies was one increase in self- and other-vulnerability to AIDS--an increase attributable, with marginal significance, only to girls. Discussed implications for health promotion and differences between assessment approaches.

Protein kinase C in rat cerebral microvessels

Activation of protein kinase C is a key event in the transduction of receptor-mediated extracellular signals. Little is known about the role of protein kinase C in the microcirculation of the brain. In this study, we examined protein kinase C in isolated cerebral microvessels. A technique for partial purification of protein kinase C from microvessels was employed, using Q-Sepharose batch adsorption and single-step salt elution in microfuge tubes. This procedure greatly reduced variability and increased protein kinase C specific activity in both the cytosolic and particulate fractions by nearly 50-fold. The identity of the enzyme was confirmed by its inhibition by staurosporine and bisindolylmaleimide and by its translocation in response to phorbol ester. The level of protein kinase C was assessed by [3H]phorbol ester binding and the endogenous substrates evaluated by in vitro phosphorylation studies. Finally, western blot analysis of protein kinase C isoforms indicated that the beta-isoform was present in both cytosolic and particulate fractions. The alpha-isoform was present at low levels in the cytosolic fraction, whereas the gamma-isoform was not detected.

Serum IgG and IgM levels in new and regular long-term plasmapheresis donors

This Australian study monitored the effects of monthly plasmapheresis on donor serum IgG and IgM levels in 127 new and 124 established plasma donors who donated 1014 units over a five-month period. Of the 251 donors, 3% had reduced total serum protein (TSP) levels, 7% had low IgG levels and 12% had low IgM levels prior to donation on at least one occasion over the study period. Statistical analysis showed that the TSP, IgG and IgM levels of new donors who had donated plasma on less than 10 occasions were no more likely to fall below normal than those of old donors. However, new and old donors whose IgG or IgM levels fell below normal at any time during the study had significantly lower levels of the relevant parameter on entry to the study. Followed longitudinally, IgG and IgM levels in old and new donors tended to fall, although levels fluctuated throughout the study. Statistical analysis failed to show any correlation between TSP levels and IgG or IgM levels. These parameters did not correlate significantly with the number of previous plasmaphereses, donor weight, volume collected or history of infection. This study highlighted the need for regular, specific quantitation of IgG and IgM levels as well as TSP in regular plasmapheresis donors. The frequency of testing is yet to be determined, in view of the high materials and labour costs of such a programme.

Serological detection of HBeAg and anti-HBe using automated microparticle enzyme immunoassays

Fully automated microparticle enzyme immunoassays (EIA) were developed for the detection of HBeAg (IMx HBe) and antibodies against HBeAg (IMx anti-HBe), respectively. Specimens from blood donors, diagnostic and hospital patients and individuals with a variety of infectious and immune diseases were tested both in house and at four clinical sites. The overall agreement between IMx HBe and Abbott HBe RIA/EIA was 99.7% (2985 of 2994) and between IMx anti-HBe and anti-HBe RIA/EIA was 95.8% (2330 of 2432). Almost all anti-HBe discordant specimens (94.1%, 96 of 102) were reactive by IMx anti-HBe but negative by anti-HBe RIA/EIA. off anti-HBe discordant specimens were also reactive for anti-HBc. The IMx anti-HBe assay was 2- to 4-fold more sensitive than the current RIA as determined by serial dilution of anti-HBe reactive specimens. The ability of these IMx assays to detect HBeAg and anti-HBe in 199 HBsAg reactive specimens was also evaluated. 43.7% (87 of 199) and 66.3% (132 of 199) specimens were reactive for HBeAg and anti-HBe by IMx, respectively. Only one specimen was negative for both IMx assays compared to 14 (7.0%) non-reactive for both HBe and anti-HBe RIA. There were 24 specimens (12.1%) positive for both HBeAg and anti-HBe by IMx compared to 1 (0.5%) positive by the corresponding RIAs. This increased detectability of anti-HBe in HBsAg carriers using IMx anti-HBe may result from increased sensitivity for 'free' anti-HBe and/or increased ability to detect anti-HBe in immune complex. IMx anti-HBe also detected more reactives among volunteer blood donor specimens reactive for anti-HBc but negative for HBsAg (55.5%, 86 of 155), compared to RIA (38.7%, 60 of 155). IMx anti-HBe may be useful in confirming prior exposure to HBV in blood screened positive by Corzyme.

The relationship between back pain and lead apron use in radiologists

Anecdotal experience has suggested that back pain in radiologists may result from extensive wearing of lead aprons. To investigate this possibility, we sent questionnaires to 688 radiologists in various subspecialties whose use of lead aprons varied from none to moderate to extensive. The questionnaire included both objective items that quantitated apron use and back pain and subjective items that asked, for example, if the respondent believed that lead aprons were responsible for his or her back pain. We received 236 responses (34% response rate). Objective data from those radiologists who had experienced no back pain before wearing a lead apron (179 radiologists, 26% of those surveyed) were tabulated; respondents were grouped according to age, time spent wearing a lead apron, and degree of back pain. Odds ratios were calculated. Answers to subjective questions for all respondents were tabulated. Back pain was reported by 52% of those who estimated their lead apron use at greater than or equal to 10 hr per week, the mean response, as opposed to 46% of those who wore lead aprons fewer than 10 hr a week. These and related results were not statistically significant. Our study does not prove that wearing a lead apron is a significant risk factor for the development of back pain.