HIV-1 antigen-specific and -nonspecific B cell responses are sensitive to combination antiretroviral therapy

We studied how combination antiviral therapy affects B cell abnormalities associated with HIV-1 infection, namely elevated circulating immunoglobulin (Ig)G antibody-secreting cell (ASC) frequencies and hypergammaglobulinemia. Within a few weeks of starting antiviral therapy, there is a marked decline in IgG-ASC frequency in both acutely and chronically infected people, whereas the hypergammaglobulinemia often present during chronic infection is more gradually resolved. These reductions are sustained while HIV-1 replication is suppressed. HIV-1 antigen-specific B cell responses are also affected by therapy, manifested by a rapid decline in circulating gp120-specific ASCs. Anti-gp120 titers slowly decrease in chronically infected individuals and usually fail to mature in acutely infected individuals who were promptly treated with antiretroviral therapy. Long-term nonprogressors have high titer antibody responses to HIV-1 antigens, but no detectable gp120-specific IgG-ASC, and normal (or subnormal) levels of total circulating IgG-ASC. Overall, we conclude that HIV-1 infection drives B cell hyperactivity, and that this polyclonal activation is rapidly responsive to decreases in viral replication caused by combination antiviral therapy.

Sexual behavior among U.S. high school students, 1990-1995

CONTEXT

High rates of unintended pregnancy and sexually transmitted diseases (STDs), including HIV infection, among adolescents are major public health concerns that have created interest in trends in teenage sexual activity.

METHODS

Nationally representative data from Youth Risk Behavior Surveys conducted in 1990, 1991, 1993 and 1995 are used to examine levels of sexual experience, age at first intercourse, current sexual activity and condom use at last intercourse among students in grades 9-12.

RESULTS

The proportion of students who reported being sexually experienced remained at 53-54% from 1990 through 1995, while the percentage of sexually active students who used condoms at last intercourse rose from 46% to 54% between 1991 and 1995. Black students were more likely than white students to report being sexually experienced, being currently sexually active and having had four or more lifetime sexual partners; black students also reported a significantly younger age at first intercourse. Gender differences in sexual behavior were found more frequently among black students than among white or Hispanic students.

CONCLUSIONS

Although levels of sexual experience for high school students in the United States have not risen during the 1990s, a very high percentage of students continue to be at risk for unintended pregnancy and STDs, including HIV infection.

Locomotor stereotypy produced by dexbenzetimide and scopolamine is reduced by SKF 83566, not sulpiride

Like amphetamine, scopolamine produces locomotor stereotypy (repetitive routes of locomotion) in an open field. To determine whether locomotor stereotypy is a common behavioral effect of anticholingeric agents, several doses of the anticholinergic dexbenzetimide were tested for the ability to produce locomotor stereotypy; like scopolamine, dexbenzetimide produced locomotor stereotypy. To investigate a possible role of dopamine in anticholinergic-induced locomotor stereotypy, we tested the ability of the dopamine D1 antagonist SKF 83566 and the D2 antagonist sulpiride to block the locomotor stereotypy induced by scopolamine as well as dexbenzetimide. SKF 83566 blocked scopolamine- and dexbenzetimide-induced locomotor stereotypy; sulpiride did not reduce dexbenzetimide-induced locomotor stereotypy, but enhanced scopolamine-induced locomotor stereotypy. Hyperlocomotion was reduced by both dopamine antagonists. Results are interpreted in support of the notion that dopamine is the likely candidate mediating locomotor stereotypy.

Genetic characterization of HIV type 1 from migrant workers in three South African gold mines

The phylogenetic relationships between 44 HIV-1 isolates from 43 infected subjects employed by three adjacent South African gold mines were investigated. The patients were migrant workers originating from rural areas of South Africa and the neighboring countries of Lesotho, Botswana, Swaziland, and Mozambique. Proviral HIV-1 DNA was subtyped using a heteroduplex mobility assay (HMA) based on the 700-bp V3-V5 region of the env gene. DNA sequence analysis was used to confirm the subtype designation and to determine phylogenetic relationships between isolates. All 44 HIV-1 isolates were identified as env subtype C using both HMA and phylogenetic analysis. These isolates did not show a distinct phylogenetic relatedness based on the geographic origins of the migrant workers or show close homology to other subtype C sequences from southern Africa or India. However, five clusters of closely related sequences were identified, mainly involving miners of disparate geographic origins, suggesting possible epidemiological linkage in these few cases. The characteristic tetrapeptide sequence, GPGQ, at the tip of the V3 loop of subtype C viruses was conserved in the predicted amino acid sequences of most isolates. The heterogeneity of HIV-1 sequences among migrant workers in a mining cohort suggests multiple introductions of HIV-1 subtype C into this population that are not apparently linked to the geographic origins of the patients.

A comparison of intravascular pressure monitoring system contamination and patient bacteremia with use of 48- and 72-hour system change intervals

OBJECTIVE

To determine the incidence of culture positivity in intravascular monitoring systems by comparing 48- versus 72-hour intervals for flush solution, stopcocks, and catheters on removal.

DESIGN

Prospective, quasi-experimental, random assignment.

SETTING

Intensive care units of a midwestern university medical center and a community hospital.

PATIENTS

Seventy-six critically ill adult patients, ranging in age from 24 to 96 years (X = 61.6), requiring arterial or pulmonary artery catheters.

OUTCOME MEASURE

Culture positivity of flush solution, stopcocks, or catheter tips.

INTERVENTION

Data collection was initiated at designated change intervals of 48- or 72-hours; cultures were taken of flush solution and stopcocks; catheter tip cultures were obtained on catheter removal.

RESULTS

Chi-square analyses indicated that increasing the change interval to 72 hours resulted in no significant difference in culture positivity of catheter tips. However, the difference between the 48- and 72-hour groups in culture-positivity rates of stopcocks from arterial catheters was significant (1, N = 82) = 6.86, p less than 0.01.

CONCLUSIONS

Our results showed that increasing the change interval to 72 hours did not increase the risk of catheter-associated infection or catheter-associated bacteremia. Chi-square analysis did not show an association between culture-positive stopcocks, the incidence of culture-positive catheter tips, entries into the system, or catheter-related bacteremia and a change interval that was increased to 72 hours. Thus, increasing the change interval to 72 hours does not increase the risk of infection.

Increased cesarean section rates and emerging patterns of health insurance in Shanghai, China

OBJECTIVES

This study examined the trend in cesarean section deliveries and the factors associated with it in the Minhang District of Shanghai, China.

METHODS

A representative sample of the members of 2716 households in the district were interviewed in the fall of 1993. This study analyzed the data from 1959 married women of reproductive age with at least one live birth.

RESULTS

During the past 3 decades, the proportion of infants born by cesarean section increased from 4.7% to 22.5%. Logistic regression analysis revealed that the highest cesarean section rate, which occurred in the most recent period of 1988 through 1993, was associated with form of medical payment, self-reported complications during pregnancy, higher birthweight, and maternal age. Government insurance pays all costs of cesarean sections and accounted for the highest proportion of the cesarean section rate.

CONCLUSIONS

The high rates of cesarean sections in China are surprising given the lack of the factors that usually lead to cesarean sections. The increasing cesarean section rates may be an early indication that emerging forms of health insurance and fee-for-service payments to physicians will lead to an excessive emphasis on costly, high-technology medical care in China.

High human immunodeficiency virus type 1 RNA load in the cerebrospinal fluid from patients with lymphocytic meningitis

Thirty-seven matched cerebrospinal fluid (CSF) and plasma samples from 34 human immunodeficiency virus type 1 (HIV-1)-infected patients with suspected meningitis were analyzed for levels of HIV-1 RNA and markers of inflammation. Patients with tuberculous (n = 9) or cryptococcal (n = 6) meningitis had the highest CSF virus loads, which in many cases exceeded the levels in plasma, compared with patients with meningococcal meningitis (n = 3), aseptic meningitis (n = 8), tuberculoma (n = 2), or AIDS dementia complex (n = 4) or with normal lumbar punctures (n = 3). CSF virus load correlated significantly with the number of infiltrating lymphocytes (r = .60, P < .001) but not with plasma virus load, the levels of beta2-microglobulin in the CSF, or the integrity of the blood-brain barrier. These data suggest significant intrathecal HIV-1 replication in patients with lymphocytic meningeal infections such as tuberculous and cryptococcal meningitis.

Governing at a distance: the elaboration of controls in British immigration

This article considers the possibility that aspects of recent thinking on governmentality could be applied to the delimitation of rights and elaboration of controls in the policy and practice of British immigration over the period of Conservative rule. First, the complex of external strategies which interact to control and inhibit migration, including the discursive assertion of sovereign boundaries in the face of moves towards a frontier-free Europe are reviewed. Then, turning to official expressions of concern over public funds, the centrality of this rationale in the drive for correspondence between benefit regulations and immigration rules is documented. This drive, it is argued, is a key tactic in the development of internal controls, both as a basis for interagency cooperation and the means by which service providers can be encouraged to police migration. Finally, the paper shows how the rationality dictating these changes has itself been questioned and further elaborates the limits of "governmentality" in practice.

Amphetamine-induced locomotor stereotypy in rats is reduced by a D1 but not a D2 antagonist

Amphetamine produces locomotor stereotypy (repetitive routes of locomotion) in an open field. In this research we tested the ability of the D1 antagonist SKF 83566 and the D2 antagonist sulpiride to block the locomotor stereotypy produced by 2 mg/kg amphetamine. SKF 83566 decreased amphetamine-induced locomotor stereotypy; sulpiride had no consistent effect on amphetamine-induced locomotor stereotypy. There was no evidence that either antagonist potentiated the effect of the other.

Osteopathia striata with cranial sclerosis: highly variable phenotypic expression within a family

We report a four-generation family, with five individuals affected by osteopathia striata with cranial sclerosis (OS-CS). The family illustrates the wide spectrum of gene expression in this autosomal dominant condition. Of particular note is the unusually severe expression in the proband, who exhibits virtually all of the reported associations of the syndrome. Proximal osteolysis of the fibula and congenital urological abnormalities, in the proband, and holoprosencephaly sequence, in the proband's sister, have not previously been described in the syndrome.

Improvement in outcome of children with Wilms' tumour in South Australia over the last 30 years

OBJECTIVE

To evaluate the outcome of children with Wilms' tumour over the last 30 years in South Australia. To compare the outcome of children treated before and after 1982, when standard treatment protocols were introduced.

METHODOLOGY

Management approaches, survival rates and side-effects of treatment were identified from case notes. Pathology slides were reviewed to ensure all children were correctly diagnosed with Wilms' tumour.

RESULTS

Children treated for Wilms' tumour prior to 1982 had an overall survival rate of 54%. Since 1982 there has been a significant improvement in outcome and the current survival rate is now 85%. Children treated since 1982 have also experienced fewer treatment related side-effects than children treated prior to 1982.

CONCLUSIONS

There has been substantial improvement in survival from childhood Wilms' tumour over the past 30 years in South Australia. This is likely to be due to a combination of factors including standardization of treatment, tailoring of treatment to stage and histology, improved perioperative care, enhanced radiological techniques and higher levels of collaboration between relevant specialists.

Comparison of two question sequences for assessing pregnancy intentions

Unintended pregnancies can have serious health, social, and economic consequences. Such pregnancies may be unwanted (a baby is not wanted at any time) or mistimed, yet wanted (a baby is wanted eventually). Intended pregnancies are those conceived when desired. Reproductive health survey respondents' understanding of these concepts and validity of survey results may be affected by question order and wording. Using a randomized crossover design, National Survey of Family Growth (NSFG) and Demographic and Health Survey (DHS) intendedness questions were asked in a 1993 survey of Arizona women aged 18-44 years. Of 2,352 ever-pregnant respondents, 25% gave discordant responses to DHS and NSFG questions about the most recent pregnancy. Age, marital status, household income, education, parity, time since pregnancy, and outcome of pregnancy were significantly predictive of discordant responses. DHS and NSFG questions yielded similar prevalence estimates of intendedness and wantedness; but young, unmarried respondents gave more "mistimed" responses on whichever question was asked later. Classifying pregnancies as intended, mistimed, or unwanted may be a problem for women who have not decided on lifetime reproductive preferences. Approaches to improving survey validity include addressing ambivalence, clarifying the definition of "unwanted," and, for young, unmarried women, not attempting to classify unintended pregnancies as mistimed or unwanted.

Identification of cell subsets expressing intracytoplasmic cytokines within HIV-1-infected lymph nodes

OBJECTIVE

To describe the endogenous cytokine profile of HIV-1-infected lymph nodes (LN) and to identify the phenotype of individual cells expressing intracytoplasmic cytokines.

DESIGN AND METHODS

Whole LN biopsies were collected from three HIV-seronegative controls and four HIV-1-positive individuals with persistent generalized lymphadenopathy. Three had established infection (Centers for Disease Control and Prevention 1993 criteria, stages A2, C1 and C3) and one was undergoing seroconversion illness. A combination of three methods was used to assess the impact of HIV-1 on LN architecture and endogenous cytokine expression. Immunocytochemistry was used to locate follicular dendritic cells (FDC), interdigitating cells and T and B cells. Reverse transcriptase-polymerase chain reaction was used to assess mRNA for interleukin (IL)-1 beta, IL-2, IL-4, IL-6, IL-10, tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma in collagenase-digested LN cells. Three-colour flow cytometry was used to identify intracytoplasmic cytokine expression within cell subsets.

RESULTS

Germinal center (GC) hyperplasia was observed in LN from two patients with established HIV-1 infection, and the third, coinfected with Mycobacterium tuberculosis, showed extensive necrosis. In the patient undergoing seroconversion, there was an extensive FDC network within the expanded and confluent GC which covered expansive areas of the LN. There was varied expression of IL-1 beta, IL-4, IL-6, IL-10 and TNF-alpha mRNA from the four HIV-1-infected LN and the patient undergoing seroconversion showed evidence for a mixed cytokine profile, which also included IL-2 and IFN-gamma. Flow cytometry revealed intracytoplasmic IL-1 beta protein restricted to cells expressing CD19, CD21 and CD38 antigens.

CONCLUSIONS

Cytokines were detected in freshly isolated HIV-1-infected LN cells without requiring an exogenous stimulus. Seroconversion was associated with an expanded FDC network within enlarged GC, bounded by defined mantle zones containing B cells. There was diverse cytokine mRNA expression and IL-1 beta protein was restricted to cells expressing B-cell-associated antigens.

Chronic flexor tenosynovitis: missed diagnosis for a decade

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Pregnancy, abortion, and birth rates among US adolescents--1980, 1985, and 1990

OBJECTIVE

To analyze pregnancy, abortion, and birth rates among US adolescent girls in 1980, 1985, and 1990.

DESIGN

Retrospective analysis of trends in data on pregnancies, abortions, and births.

POPULATION

US adolescent girls aged 13 to 19 years.

MAIN OUTCOME MEASURES

Pregnancy, abortion, and birth rates (with and without adjustment for sexual experience) among teenaged girls aged 15 to 19 years and girls under 15 years.

RESULTS

Although pregnancy rates among all teenaged girls 15 to 19 years old remained fairly stable from 1980 to 1985, they increased by 9% during the last half of the decade, totaling 95.9 pregnancies per 1000 teenaged girls 15 to 19 years old by 1990. Because rates of sexual experience increased even faster, pregnancy rates among sexually experienced teens aged 15 to 19 actually declined between 1980 and 1990 by approximately 8%. Abortion rates among these teens remained stable during the 1980s, with 35.8 and 36.0 abortions per 1000 in 1980 and 1990, respectively. As with overall pregnancy rates, abortion rates among these sexually experienced teenaged girls declined during the 1980s. Between 1980 and 1985, birth rates among teenaged girls aged 15 to 19 years declined by 4%, but they increased by 18% during the latter half of the decade, totaling 59.9 births per 1000 in 1990. Among these sexually experienced teenagers, birth rates also declined between 1980 and 1985 and then increased over the next 5 years. In 1990, pregnancies and abortions among girls younger than 15 years accounted for only 3% of all adolescent pregnancies and abortions. However, the number of births among these younger adolescents increased by 15% over the decade. In that age group, trends in pregnancy, abortion and birth rates over the decade were similar to those for older teens. However, during the late 1980s, the abortion rate declined and the pregnancy rate remained stable, resulting in a 26% increase in the birth rate.

CONCLUSIONS

Despite efforts to reduce adolescent pregnancy in the United States, pregnancy and birth rates for that group continue to be the highest among developed countries. Considering that 95% of adolescent pregnancies are unintended, increased efforts to prevent these pregnancies are warranted.

Effects of crack cocaine on neurocognitive function

Because crack cocaine appears to have a preferential effect on the metabolic and electrophysiological activity of the frontal and temporal regions of the brain (Pascual-Leone et al., 1991a, 1991b; Volkow, 1992), we hypothesized that cognitive measures of those regions would be impaired in crack cocaine users relative to measures in normal volunteers. We used logistic regression to determine the relationship of cocaine usage to neuropsychological test performance. We compared 38 patients with an average of 3.6 (SD = 2.5) years of crack cocaine use and 24.5 (SD = 28.1) days of abstinence to 54 normal volunteers on a battery of neuropsychological tests. Statistical adjustments were made for the effects of age, education, socioeconomic class, and level of depression. Our findings were mixed with regard to purported measures of executive/frontal functioning, with worse performance associated with cocaine usage on the Booklet Categories Test, but better performance associated on others (number of categories on the Wisconsin Card Sorting Test, Controlled Oral Word Association). Cocaine usage was associated with impairment on measures of spatial, but not verbal memory, confrontation naming, and Trail-making Test, Part B, a measure of perceptual-motor speed and cognitive flexibility. In summary, it appears that continuous crack cocaine use produces a dissociative pattern in neuropsychological test performance with improvement on some measures, but deterioration on others. The permanence of these effects remains to be determined with longitudinal studies.