Glutathione and immune function

The immune system works best if the lymphoid cells have a delicately balanced intermediate level of glutathione. Even moderate changes in the intracellular glutathione level have profound effects on lymphocyte functions. Certain functions, such as the DNA synthetic response, are exquisitely sensitive to reactive oxygen intermediates and, therefore, are favoured by high levels of the antioxidant glutathione. Certain signal pathways, in contrast, are enhanced by oxidative conditions and favoured by low intracellular glutathione levels. The available evidence suggests that the lymphocytes from healthy human subjects have, on average, an optimal glutathione level. There is no indication that immunological functions such as resistance to infection or the response to vaccination may be enhanced in healthy human subjects by administration of glutathione or its precursor amino acid cysteine. However, immunological functions in diseases that are associated with a cysteine and glutathione deficiency may be significantly enhanced and potentially restored by cysteine supplementation. This factor has been studied most extensively in the case of human immunodeficiency virus (HIV)-infected patients who were found to experience, on average, a massive loss of S equivalent to a net loss of approximately 4 g cysteine/d. Two randomized placebo-controlled trials have shown that treatment of HIV-infected patients with N-acetyl-cysteine caused in both cases a significant increase in all immunological functions under test, including an almost complete restoration of natural killer cell activity. It remains to be tested whether cysteine supplementation may be useful also in other diseases and conditions that are associated with a low mean plasma cystine level and impaired immunological functions.

Seroprevalence of HIV infection among pregnant women in the Veneto region (north-east Italy)

A heterogeneous population of 4396 consecutive pregnant women (86.6% indigenous, 13.4% immigrants) attending the Department of Obstetrics and Gynecology of the University of Padua (north-east Italy) were counselled and tested for HIV infection between September 1995 and December 1997. Sociodemographic and sanitary data were collected on each case. Anti-HIV prevalence was 0.57%. Intravenous drug use and foreign birth accounted for 28% and 24%, respectively, of the anti-HIV positive cases; 44% of the HIV-positive subjects reported no risk factors. In the logistic regression HIV positivity proved independently associated with intravenous drug use (adjusted OR 76. 6), sexually transmitted diseases (adjusted OR 13.2), unmarried status (adjusted OR 4.8), birth outside the European Union (EU) (adjusted OR 3.1) and age (adjusted OR 1.1). Heterosexual HIV spread appears to be a major concern. The monitoring of trends in HIV infection among subgroups should be continued in order to control the AIDS epidemic appropriately both by promoting HIV counselling and individual care, and by watching for changes in the social background.

Identification of risk factors in blood donors found to have HIV infection

To ascertain whether current screening procedures for human immunodeficiency virus (HIV) infected blood can be improved, a study of blood donors found by Mersey and North Wales Blood Centre to be HIV positive was made. In total 22 donors were identified, of which 16 were referred to the Department of Genito-Urinary Medicine (GUM) in Liverpool. Most (9/16) should have been excluded from donating because of recognized risk factors. However, in 7 cases no such identifiable factors were found. Although the risk of transfusion transmitted infection is small, there is an argument for testing donated blood for HIV RNA by nucleic acid technology.

Youth and tattoos: what school health personnel should know

Though tattooing has been practiced by various cultures for centuries, this art form has undergone dramatic changes the past few decades. Today, tattoos appeal to diverse populations and mainstream culture. The proliferation of tattooing prompted increased concern for safety and awareness of hazardous conditions. Transmission of infectious diseases, such as hepatitis B and C, and theoretically, HIV, can occur when proper sterilization and safety procedures are not followed. While there are many populations at risk, a critical at-risk group is adolescents. Tattooing among adolescents is a risk-taking behavior that warrants the attention of health education in assisting adolescents in becoming informed decision-makers. Teaching and advocacy strategies are suggested, and roles for school health personnel are presented.

Risk of HIV infection as a function of the duration of intravenous drug use: a non-parametric Bayesian approach

We analyse the elapsed time between intravenous (IV) drug initiation and HIV infection in a cohort of 972 injecting drug users attending a hospital detoxification unit. We use the time of seroconversion instead of the time of HIV infection because the date of HIV infection is rarely known and the gap between these two times is negligible (around one to three months). Although seroconversion time cannot be determined exactly, it can be inferred at least to within an interval. This seroconversion interval is determined from the dates of HIV antibody tests, if available. The data is consequently interval-censored. We estimate the distribution function of the elapsed time from IV drug initiation to seroconversion as well as the risk of seroconversion by means of a non-parametric Bayesian approach. The analysis is conducted according to the following four calendar periods: before or at 1980; between 1981 and 1985; between 1986 and 1991; after or at 1992 where the IV drug use was initiated. The methodology used is based on an alternating conditional sampling algorithm. The Bayesian approach allows not only the incorporation of prior beliefs about the distribution function, but also the analysis of the risk of seroconversion without assuming restrictive parametric models. Furthermore, the estimator for the distribution function is smooth and thus differences between groups can be easily interpreted.

Human immunodeficiency virus infection in rural areas and small cities of the southeast: contributions of migration and behavior

The design of education and prevention strategies to stem the spread of human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) in rural areas depends on having accurate patterns of risk behavior and transmission in local areas. Interviews were conducted with people in rural areas and small cities in Delaware, Florida, Georgia and South Carolina who were at least 18 years old and infected with HIV in order to describe demographic characteristics, migration patterns and risk behaviors. Interviews were conducted with 608 people. Most respondents were male (66 percent), black (63 percent of men, 85 percent of women) and had been infected through sexual contact (67 percent of men, 66 percent of women). Most (65 percent) had lived away from a rural area or small city for at least one month; of those, 71 percent had moved from an urban area. Twenty-seven percent of respondents indicated they had been infected locally. People with a history of injection drug use were less likely to have been infected locally than those who had no history of injection drug use (6 percent vs. 26 percent among men, 3 percent vs. 40 percent among women, P < 0.001). Further understanding of the role of socioeconomic factors in HIV transmission in rural areas and small cities is needed. Programs designed to prevent HIV acquisition among people living in rural areas and small cities in the Southeast should focus on sexual behavior.

Morphine induces gene expression of CCR5 in human CEMx174 lymphocytes

All HIV-1 strains studied to date use CCR5, CXCR4, or both receptors to enter cells. Simian immunodeficiency virus (SIV) infection of non-human primates has served as a useful model for understanding AIDS pathogenesis in humans. Research on several genetically divergent SIV isolates has revealed that SIV uses CCR5, and not CXCR4, for entry. CEM x174, a human lymphoid cell line, has been routinely used to cultivate and maintain various SIV strains. However, questions have arisen about how CEM x174, which reportedly was unable to express detectable amounts of CCR5 transcripts, efficiently supports the growth of SIV. In searching for an answer, we resorted to a sensitive competitive reverse transcriptase-polymerase chain reaction procedure in an attempt to detect as well as quantify the amount of CCR5 expression. Here we present our findings, which indicate that CEM x174 indeed expresses CCR5 and that the amount of CCR5 is increased in cells pretreated with morphine. These results correlate well with our previous observations that morphine treatment causes CEM x174 cells to be more susceptible to SIV infection. Similar morphine effect was not observed on CEM x174 cells infected with simian retroviruses, which do not depend on CCR5 for entry. These findings suggest a plausible mechanism whereby opiate drug users render themselves more susceptible to HIV infection, thereby explaining the vast prevalence of HIV infection among endemic drug use populations.

Nonoccupational HIV postexposure prophylaxis: a new role for the emergency department

Despite numerous primary prevention campaigns, new cases of HIV infection are occurring at high rates. Postexposure prophylaxis (PEP) after possible HIV exposures from sexual encounters or injection drug use may prove to be a worthwhile means of reducing HIV infection. Although there are no studies that directly demonstrate its efficacy, indirect support comes from animal and human studies. Multiple animal studies have shown that antiretroviral medications can reduce simian immunodeficiency virus infections if given early and for a prolonged period. A study of health care workers suggests that zidovudine taken after needlestick injuries can dramatically reduce HIV seroconversion. Zidovudine and nevirapine use recently showed great reductions in perinatal HIV transmission. Studies of dendritic and T-cell processing of simian immunodeficiency virus and HIV indicate that antiretroviral medications taken soon after a viral exposure may terminate viral replication. Regimens of 2 or 3 antiretroviral medications have been suggested as prophylactic measures after certain exposures. Even though limited experience exists with these populations, HIV PEP is most likely safe in pregnancy and for children. Emergency departments are encouraged to anticipate the probable demands for nonoccupational HIV PEP by establishing protocols for its rapid provision and ensuring proper follow-up care.

[Analysis on the intervention effect of HIV/AIDS cases]

OBJECTIVE

To study the effect of a comprehensive intervention strategy on the HIV infected individuals and their families.

METHODS

Eleven HIV positive persons and their families were included to a comprehensive intervention strategy including routine surveillance, safer sex education and improving the status of hygiene. The outcome was compared with 2 fully developed AIDS cases who were not included to the intervention strategy.

RESULTS

Of those HIV positive persons, that subjected to the intervention strategy, none had developed to AIDS, with only 1 transmitted HIV to his spouse among the 6 married individuals. All of their families were stable. Of those that not had been subjected, 2 individuals developed to AIDS and transmission in family was confirmed.

CONCLUSION

The comprehensive intervention strategy on HIV/AIDS was effective which could the possibility of HIV in-family transmission and enhance the quality of life and the stability of their families.

The HIV epidemic and the state of its surveillance in Ethiopia

A review of the information on the HIV epidemic in Ethiopia is important to guide policy and action. Published and unpublished reports and surveillance data from records of governmental and non-governmental institutions were examined to assess the extent of the epidemic. It appears that the HIV/AIDS epidemic has affected a large segment of the urban population. Surveillance data from pregnant women attending antenatal clinics indicate a decreasing trend in the prevalence of HIV in Addis Ababa. Similarly, data from blood donors from the majority of transfusion centres in the country indicate a decrease in prevalence. However, further studies will be required to establish the validity of these findings. Currently available data are not adequate to accurately measure the level of infection in rural areas where 85% of the population live. Outside of Addis Ababa, in places where ANC-based sentinel surveillance are operational, the systems are not fully supported by quality control. Thus, there are concerns regarding the validity of reported results. The impact of HIV/AIDS epidemic in Ethiopia needs to be further quantified both in its burden of diseases and its impact on the urban and rural economy and society. It is, therefore, important that effort and adequate resources are put into strengthening surveillance systems.

Birds of a feather: using a rotational box plot to assess ascertainment bias

BACKGROUND

Comparability of study participants with non-participants is customarily assessed by contrasting the distributions of sociodemographic characteristics. Such comparisons do not necessarily provide insight into whether or not participants of a given subgroup are similar to non-participants of the same subgroup. A geographical information system (GIS) may provide such insight by visually displaying the spatial distributions of participants and non-participants. In a previously reported study of heterosexuals at elevated risk for human immunodeficiency virus (HIV), traditional methods suggested distributional differences in the demographic characteristics of participants and non-participants.

METHODS

Based on residential address co-ordinates for each subgroup member, we used the subgroup's centroid as the origin and constructed a 360 degrees series of overlapping box plots of the distance of subgroups members to the origin, thereby producing closed polygons for each of the box plot demarcators.

RESULTS

These rotational box plots revealed similar geographical distributions for most participant and non-participant subgroups, with the exception of African-American men and women.

CONCLUSIONS

Observed differences resulted in part from the study design, and provided some insight into sampling problems encountered in social network studies. Based on Tobler's supposition that 'nearby things tend to be alike', the rotational box plot is a useful additional tool for investigating sample bias.

Galactorrhoea and hyperprolactinaemia associated with protease-inhibitors

We describe four patients with galactorrhoea as an isolated endocrine abnormality after use of protease inhibitors (PIs) as part of both highly active antiretroviral therapy (HAART) and postexposure prophylaxis (PEP). This reaction may be a direct effect of PIs or may be indirectly mediated by the effect of PIs on the cytochrome P450 system, thus potentiating the dopamine antagonist effects of other drugs.

Haemophilia care in central Scotland 1980-94. I. Demographic characteristics, hospital admissions and causes of death

To estimate the resources required to manage patients with haemophilia in Scotland, we studied the demographic features, hospital admissions and causes of deaths for individuals with haemophilia A and B and von Willebrand disease, treated with blood products, during the period 1980-94 living in central Scotland. Data were obtained from 413 adults and children (93% ascertainment). The age distribution in 1980 revealed a paucity of individuals over 60 years but the number in this age group increased over the study period. Of those with haemophilia A and B, 63 and two respectively, became HIV positive. Hospital admissions rose from 103 to 168 per annum; the number of annual bed days utilized also increased, but there was marked annual fluctuation (790-1832). The rate of admission was greater for those with severe haemophilia A and this increased during the 15-year period mainly due to the clinical consequences of human immunodeficiency virus (HIV) and hepatitis C virus (HCV). The admission rate for haemophilia B was significantly lower than that for haemophilia A, and was similar for all degrees of severity of the disorder. Throughout the 15-year period the incidence of admissions for acute bleeds was constant, as was the average duration in hospital. For those with a factor VIII inhibitor, the rate of admission was about double the rate of those without an inhibitor, although the duration of hospital stay was similar for both groups. There were 61 deaths; the death rate increased during the study period principally due to HIV and HCV, and 12 patients died from haemorrhage. We conclude that: (i) the life expectancy for haemophiliacs in Scotland was generally increasing, although HIV and HCV caused increasing mortality and morbidity (as shown by the increase in hospital admissions); (ii) hospital bed usage for the treatment of acute bleeds continued to be required, but fluctuated greatly; and (iii) the clinical impression that haemophilia B is less clinically severe than haemophilia A is confirmed by objective data. The planning implications for haemophilia care in Scotland and similar countries are discussed.

Research, politics, and needle exchange

We now have had 15 years of public discussion of and research on needle exchange programs. The data have shown these programs to be usually, but not always, effective in limiting HIV transmission among injection drug users. Needle exchange programs are conceptualized within a larger framework of providing ready availability of sterile injection equipment for injection drug users. Continuing research is clearly needed regarding how to maximize the availability of sterile injection equipment and how to integrate this with other needed health and social services for drug users. Many initial opponents of needle exchange programs have become supporters of the programs. The number of programs in the United States has been increasing by about 20% per year, and this can be considered substantial progress in reducing HIV infection among injection drug users. Important opposition remains, however, based primarily on the symbolic values expressed in government support for the programs. These value conflicts over needle exchange, which have existed since it was first considered in the United States, cannot be resolved with data. In the late 1980s, the value conflicts greatly hampered the collection of relevant data--there was no federal funding of research on needle exchange programs. Currently, there is considerable research on needle exchange, but many researchers are quite concerned about possible misuse of findings. This may be considered progress to an important but modest degree. Whether current and future research will be used to improve HIV prevention efforts remains to be seen.

Modulation of the ceramide level, a novel therapeutic concept?

The sphingomyelin (SM) pathway is an ubiquitous and evolutionarily conserved signaling system in which ceramide (CA), generated from SM by the action of various isoforms of sphingomyelinases (SMases) functions as an important second messenger. Recent evidence suggests that branching pathways of sphingolipid metabolism mediate either apoptotic or mitogenic responses depending on cell type and the nature of the stimulus. Events involving SM metabolites and CA in particular include proliferation, differentiation and growth arrest as well as the induction of apoptosis. An improved understanding of SMase-dependent signaling may afford relevant insights into the pathogenesis of diseases and provide novel strategies and selective targets for a therapeutic intervention e.g. in cancer, cardiovascular and neurodegenerative diseases, HIV and septic shock. This article briefly summarizes the role of SMases in signaling pathways, its potential contribution in the development and maintenance of various pathobiological states and analyzes the perspective of a potentially isotype-specifc inhibition of SMases as a novel therapeutic concept.

Secret encounters: black men, bisexuality, and AIDS in Alabama

Black men suffer the highest rates of HIV infection in Alabama. However, little is known about the HIV risks of this sector of the population, primarily because the current public health focus is on women and children. The dearth of research on HIV risk among black men in Alabama is addressed by drawing on focus group, elicitation, and key informant data from an ongoing epidemiologic study on AIDS in that state. These hypothesis-generating qualitative interviews were used to identify three high-risk scenarios: "sex for money or drugs"; "prison sex"; and "sneaky sex" by married or nominally heterosexual men. It was found that covert and unprotected sex among bisexually active black men was commonplace for reasons that included prostitution, habituation to same-sex relations during incarceration, and the desire to maintain a facade of heterosexuality in homophobic communities. It was concluded that bisexual activity is highly correlated with secrecy and unprotected sex. The risks of bisexuality among black men are exacerbated by incarceration, homophobia, drug use, and the prison and public health focus on surveillance rather than prevention.

Higher-dimensional separation principle for the analysis of relaxation oscillations in nonlinear systems: application to a model of HIV infection

In this paper, geometric and singular perturbation arguments are utilized to develop a separation condition for the identification of limit cycles in higher-dimensional (n > or = 4) dynamical systems characterized by highly diversified time responses, in which there exists an (n - 3)-dimensional subsystem which quickly reaches a quasi-steady state. The condition, which has been used up to now to analyze relaxation oscillation in slow-fast systems, is extended to accommodate dynamical systems in which more state variables are involved in a special manner which still allows for the use of singular perturbation techniques. Application is then made to a model of human immunodeficiency virus infection in T helper (TH) cell clones with limiting resting TH cell supply.

The association between cocaine use and HIV/STDs among soup kitchen attendees in New York City

We examined the associations of cocaine use with HIV/sexually transmitted diseases (STDs) in a sample of 184 soup kitchen attendees using a mobile medical van in Manhattan (male = 66%; black or Hispanic = 81%; cocaine use, primarily crack = 75%; ever injected drugs = 22%). In addition to confirming the association between years of cocaine use and HIV antibodies in this sample (odds ratio [OR] = 2.11; p <.05) we examined the pattern of associations of cocaine use and non-HIV STDs under the hypothesis that the strength of an association depends on the efficiency of sexually transmitting a particular STD (high, moderate, and low for syphilis, hepatitis B and hepatitis C, respectively). As predicted, years of cocaine use was strongly associated with syphilis (OR = 2.07; p <.05), moderately associated with hepatitis B core antibodies (OR = 1.50; p <.05), and not significantly associated with hepatitis C antibodies (OR = 1.48; p >.05). A reverse pattern of associations between opiate use (injection drug use) and the three STDs points to the singular significance of cocaine use in the sexual transmission of STDs, and by inference, HIV. This conclusion is further bolstered by correlations of biologic (hair assays) and self-reported measurements of cocaine use (but not opiates) with self-reports of high risk sexual behavior among the women (number of partners and selling sex) and men (number of partners and buying sex). These data underscore the need for effective cocaine treatment and HIV interventions tailored to the large numbers of cocaine users in inner cities.