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Background: Human papillomavirus (HPV)-associated anogenital malignancies occur frequently in patients with human immunodeficiency virus (HIV) infection and the acquired immunodeficiency syndrome (AIDS). The purpose of our study was to determine if the high frequency of these cancers is due to lifestyle factors associated with both HPV and HIV infections or to immunosuppression following HIV infection.Methods: We studied invasive and in situ HPV-associated cancers among 309 365 U.S. patients with HIV infection/AIDS (257 605 males and 51 760 females) from 5 years before the date of AIDS onset to 5 years after this date. Sex-, race-, and age-standardized ratios of observed-to-expected cancers served as measures of relative risk (RR). Trend tests were used to evaluate changes in the RRs during the 10 years spanning AIDS onset. All statistical tests were two-sided.Results: All HPV-associated cancers in AIDS patients occurred in statistically significant excess compared with the expected numbers of cancers. For in situ cancers, overall risks were significantly increased for cervical (RR = 4.6; 95% confidence interval [CI] = 4.3-5.0), vulvar/vaginal (RR = 3.9; 95% CI = 2.0-7. 0), anal (in females, RR = 7.8 [95% CI = 0.2-43.6]; in males, RR = 60.1 [95% CI = 49.2-72.7]), and penile (RR = 6.9; 95% CI = 4.2-10.6) cancers, and RRs increased during the 10 years spanning AIDS onset for carcinomas in situ of the cervix (P: for trend <.001), vulva/vagina (P: for trend =.04), and penis (P: for trend =.04). For invasive cancers, overall risks were significantly increased for cervical (RR = 5.4; 95% CI = 3.9-7.2), vulvar/vaginal (RR = 5.8; 95% CI = 3.0-10.2), and anal (RR = 6.8; 95% CI = 2.7-14.0) cancers in females and for anal (RR = 37.9; 95% CI = 33.0-43.4), penile (RR = 3. 7; 95% CI = 2.0-6.2), tonsillar (RR = 2.6; 95% CI = 1.8-3.8), and conjunctival (RR = 14.6; 95% CI = 5.8-30.0) cancers in males. However, RRs for invasive cancers changed little during the 10 years spanning AIDS onset.Conclusions: HPV-associated malignancies occur at increased rates in persons with HIV/AIDS. Increasing RRs for in situ cancers to and beyond the time of AIDS onset may reflect the gradual loss of control over HPV-infected keratinocytes with advancing immunosuppression. However, the lack of a similar increase for invasive HPV-associated cancers suggests that late-stage cancer invasion is not greatly influenced by immune status. [ABSTRACT FROM AUTHOR]

Context: Population-based data on cancers associated with acquired immunodeficiency syndrome (AIDS) in children are lacking.Objective: To determine risk of pediatric AIDS-associated cancers.Design, Setting, and Participants: Using records from 11 locations in the United States for varying periods between 1978 and 1996, we linked data for children aged 14 years and younger at AIDS diagnosis to local cancer registry data.Main Outcome Measures: Cancer frequency and, in the 2-year post-AIDS onset period, cancer incidence and relative risk (RR; measured as standardized incidence ratio), by cancer type.Results: Among 4954 children with AIDS, 124 (2.5%) were identified as having cancer before, at, or after AIDS onset, including 100 cases of non-Hodgkin lymphoma (NHL), 8 of Kaposi sarcoma (KS), 4 of leiomyosarcoma, and 2 of Hodgkin disease; there were 10 other or unspecified cancers. Expected numbers for all cancers identified in the study sample, based on population rates (using area-specific registry data), were less than 1. In the first 2 years after AIDS diagnosis (5485 person-years), NHL incidence was 510 per 100,000 person-years (RR, 651; 95% confidence interval [CI], 432-941). Median time for developing NHL after AIDS diagnosis was 14 months (range, 3-107 months). The most common type of NHL was Burkitt lymphoma. However, the risk of primary brain lymphoma (91 per 100,000 person-years) was especially high (RR, 7143; 95% CI, 2321-16,692), and 4 cases were diagnosed more than 2 years (range, 37-98 months) after AIDS onset. Leiomyosarcomas also tended to occur several years after AIDS onset, with 3 of the 4 cases occurring 33 to 76 months after AIDS diagnosis, whereas KS was reported only at or within 2 years of AIDS diagnosis. Hodgkin disease risk was also significantly increased (RR, 62; 95% CI, 2-342).Conclusions: The spectrum of AIDS-associated pediatric cancers resembled that seen in adults, with the addition of leiomyosarcoma. Both primary brain lymphomas and leiomyosarcomas tended to occur in children surviving several years after AIDS onset. Because the expected numbers of these cancers in this population were less than 1 and because of the small numbers of some types of observed cancers, the RR estimates are imprecise and caution is warranted in their interpretation. JAMA. 2000;284:205-209 [ABSTRACT FROM AUTHOR]

Objective: Tonsillar squamous cell carcinoma (SCC) may differ etiologically from other oral cancers. The aim of this study was to provide a detailed description of the incidence patterns of tonsillar SCC in the United States.Methods: Population-based incidence data from the Connecticut Tumor Registry (period 1945-1994) and from the SEER program (period 1973-1995) were used to calculate age-standardized (US 1970) and age-specific incidence rates and confidence intervals (CIs). Linear regression was used to evaluate trends.Results: The incidence of tonsillar SCC increased fourfold among white women in Connecticut during 1945-1994 but remained rather constant in white men. During 1973-1995, incidence rates per million person-years were considerably higher in blacks (31.6; 95% CI: 29.0-34.4 in men, and 9.6; 95% CI: 8.3-10.9 in women) than whites (14.8; 95% CI: 14.3 15.3 in men, and 6.1; 95% CI: 5.8-6.4 in women). Men, but not women, who were younger than 60 years experienced significant annual increases in tonsillar SCC incidence during 1973-1995 (2.7% in blacks and 1.9% in whites). No similar increases occurred for oral SCC at non-tonsillar sites.Conclusion: Incidence rates of tonsillar SCC vary considerably by sex, race and time in a way that cannot be explained by changes in tonsillectomy practices alone. Changes in environmental risk factors, including changes in smoking patterns and an increase in oral human papillomavirus infections, may have contributed. [ABSTRACT FROM AUTHOR]

Context: Understanding the risk of human immunodeficiency virus (HIV) transmission through breastfeeding is essential for advising HIV-infected mothers and formulating public health policy recommendations.Objective: To measure the frequency, timing, and risk factors of HIV transmission through breast milk.Design: Prospective cohort study conducted between 1994 and 1997, with follow-up of infants through 24 months of age.Setting: Postnatal clinic of tertiary care hospital, Blantyre, Malawi.Participants: A total of 672 infants (HIV-negative at birth) born to HIV-infected women who had not received antiretroviral drugs during or after pregnancy.Main Outcome Measure: Incidence of HIV in breastfed infants by age and maternal and infant risk factors for HIV transmission, using proportional hazard models to derive risk ratios (RRs) and 95% confidence intervals (CIs).Results: Forty-seven children became HIV-infected while breastfeeding but none after breastfeeding had stopped. The cumulative infection rate while breastfeeding, from month 1 to the end of months 5, 11,17, and 23, was 3.5%, 7.0%, 8.9%, and 10.3%, respectively. Incidence per month was 0.7% during age 1 to 5 months, 0.6% during age 6 to 11 months, and 0.3% during age 12 to 17 months (P = .01 for trend). The only factors significantly associated with low risk of postnatal HIV transmission in a multivariate model were high maternal parity (RR, 0.23; 95% CI, 0.09-0.56) and older maternal age (RR, 0.44; 95% CI, 0.23-0.84).Conclusions: Our data suggest that the risk of HIV infection is highest in the early months of breastfeeding, which should be considered in formulating breastfeeding policy recommendations. [ABSTRACT FROM AUTHOR]

Background: Large simple trials which aim to study therapeutic interventions and epidemiological associations of human immunodeficiency virus (HIV) infection, including perinatal transmission, in Africa may have substantial rates of loss to follow-up. A better understanding of the characteristics and the impact of women and children lost to follow-up is needed.Methods: We studied predictors and the impact of losses to follow-up of infants born in a large cohort of delivering women in urban Malawi. The cohort was established as part of a trial of vaginal cleansing with chlorhexidine during delivery to prevent mother-to-infant transmission of HIV.Results: The HIV infection status could not be determined for 797 (36.9%) of 2156 infants born to HIV-infected mothers; 144 (6.7%) with missing status because of various sample problems and 653 (30.3%) because they never returned to the clinic. Notably, the observed rates of perinatal transmission were significantly lower in infants who returned later for determination of their infection status (odds ratio = 0.94 per month, P = 0.03), even though these infants must have had an additional risk of infection from breastfeeding. In multivariate models, infants of lower birthweight (P = 0.003) and, marginally, singletons (P = 0.09) were less likely to return for follow-up. The parents of infants lost to follow-up tended to be less educated (P < 0.001) and more likely to be in farming occupations, although one educated group, teachers and students, were also significantly less likely to return. Of these variables, infant birthweight, twins versus singletons, and maternal education were also associated with significant variation in the observed risk of perinatal transmission among infants of known HIV status.Conclusions: Several predictors of loss to follow-up were identified in this large HIV perinatal cohort. Losses to follow-up can impact the observed transmission rate and the risk associations in different studies. [ABSTRACT FROM AUTHOR]

Seroprevalence of HHV-8 has been studied in Malaysia, India, Sri Lanka, Thailand, Trinidad, Jamaica and the USA, in both healthy individuals and those infected with HIV. Seroprevalence was found to be low in these countries in both the healthy and the HIV-infected populations. This correlates with the fact that hardly any AIDS-related Kaposi's sarcoma has been reported in these countries. In contrast, the African countries of Ghana, Uganda and Zambia showed high seroprevalences in both healthy and HIV-infected populations. This suggests that human herpes virus-8 (HHV-8) may be either a recently introduced virus or one that has extremely low infectivity. Nasopharyngeal and oral carcinoma patients from Malaysia, Hong Kong and Sri Lanka who have very high EBV titres show that only 3/82 (3.7%) have antibody to HHV-8, demonstrating that there is little, if any, cross-reactivity between antibodies to these two gamma viruses. [ABSTRACT FROM AUTHOR]

We describe new torsional oscillator experiments on3 He confined in 98.2% open aerogel. In one, we monitored the superfluid fraction of pure3 He at T << Tc while we gradually changed the sample pressure. The resulting change in density alters ξ0 of the superfluid3 He relative to the distribution of the length scales (correlations) of silica in the aerogel. We observed a T = 0 normal-to-super fluid transition at a pressure of about 6.5 bar, in marked contrast to the bulk where liquid3 He is superfluid at all pressures. In the second experiment, we measured the temperature dependence of the3 He ρs at a pressure of 21.6 bar with different amounts of4 He present in the cell. Adding 2-3%4 He slightly increases both Tc and ρs . We found that for4 He concentrations between 2% and 34%, the3 He Tc increases by a very small amount. However, ρs , which for pure3 He in aerogel at 0.5Tc is no more than 11%, falls by another factor of 7. This behavior (constant Tc , reduced ρs ) is similar to that observed in granular superconducting films where the long-range order is controlled by phase coherence between adjacent grains. [ABSTRACT FROM AUTHOR]

The appearance of the endothelial pavement pattern was studied in the pulmonary trunk, pulmonary veins, aorta, and inferior vena cava of the rat by means of silver staining of the cell borders. The endothelial cell in each of the four blood vessels was found to have its own distinctive shape, fusiform and pointed in the direction of blood flow in the case of the aorta and larger and more rectangular in the pulmonary trunk and pulmonary veins. Detailed quantitation of the dimensions and surface area of the endothelial cells in each blood vessel was carried out by a photographic technique. Pulmonary hypertension was induced in one group of rats by feeding them on Crotalaria spectabilis seeds. The endothelial pavement pattern in their pulmonary trunks became disrupted with many of the cells assuming a fusiform shape reminiscent of aortic endothelium. Many small, new endothelial cells formed in the pulmonary trunk suggesting division of cells to line the enlarging blood vessels. In contrast the endothelial cells of the inferior vena cava merely increased in size to cope with the dilatation of this vein. [ABSTRACT FROM AUTHOR]

To standardize human herpesvirus 8 (HHV-8) antibody assays for application to asymptomatic infection, a blinded comparison was done of seven immunofluorescence assays and ELISAs. Five experienced laboratories tested a serum panel from 143 subjects in 4 diagnostic groups. Except for a minor capsid protein ELISA, the other six tests detected HHV-8 antibodies most frequently in classic (80%-100%) and AIDS-related (67%-91%) Kaposi's sarcoma, followed by human immunodeficiency virus-seropositive patients (27%-60%), and least frequently in healthy blood donors (0-29%). However, these six assays frequently disagreed on individual sera, particularly for blood donor samples. Current HHV-8 antibody tests have uncertain accuracy in asymptomatic HHV-8 infection and may require correlation with viral protein or nucleic acid detection. Antibody assays are useful for epidemiologic investigations, but the absolute prevalence of HHV-8 infection in the United States cannot yet be determined. [ABSTRACT FROM AUTHOR]

Between 1972 and 1976, 585 persons attending methadone maintenance clinics at East Coast veterans hospitals were enrolled in a survey of hepatitis antibody prevalence. Sera were tested for human immunodeficiency virus (HIV) and human T lymphotropic virus (HTLV) using both HTLV-I and HTLV-II immunoblots. Clinical and death records were also reviewed. None of the sera had HIV antibodies (upper 95% confidence limit, 0.5%); however, 103 (18%) had reactivity to HTLV. The profile of reactivity suggested that these subjects had been exposed to HTLV-II rather than to HTLV-I. Prevalence was as high in the early 1970s as today and correlated with duration of drug use rather than age. Neither cancers, specific neurologic diseases, nor excess deaths from any cause (overall 14%) could be ascribed to seropositivity. Therefore, HTLV (probably HTLV-II) has been a common infection of drug users for many years but adverse outcomes following infection were not demonstrated. [ABSTRACT FROM AUTHOR]

Examines the incidence of human herpesvirus 8 among homosexual men. Indication of acquired immunodeficiency syndrome; Development of gonorrhea infections; Observation of demographic and behavioral exposures.

Objective: We sought to describe the rate, risk, trends, methods, and distribution of suicide among persons with the acquired immunodeficiency syndrome (AIDS) in the United States.Design: We used National Center for Health Statistics multiple-cause mortality data from 1987 through 1989 to identify suicides among persons with AIDS (PWAs) and public-access AIDS surveillance data to determine person-years of observation of PWAs.Patients: Residents of the United States with death certificates indicating suicide.Main Outcome Measure: Death certificates indicating both AIDS and suicide.Results: In 1987 through 1989, a total of 165 suicides among PWAs occurred in 45 states and the District of Columbia. All but one case were male. Among males the rate was 165 per 100,000 person-years of observation, 7.4-fold higher than among demographically similar men in the general population. Self-poisoning with drugs was both the most common method (35%) and the method with the highest standardized mortality ratio (35). Suicide risk for PWAs decreased significantly (P < .05) from 1987 to 1989.Conclusion: Persons with AIDS have an increased risk of suicide, and assessment of such risk should be a standard practice in their care. These assessments should be carefully considered when potentially lethal medications are prescribed. The declining trend in suicide rates between 1987 and 1989 is encouraging; possible causes include emerging therapies for human immunodeficiency virus/AIDS, better psychiatric care for these patients, and lessened social stigma against PWAs. [ABSTRACT FROM AUTHOR]

Abstract Background India has a large and evolving HIV epidemic. Little is known about cancer risk in Indian persons with HIV/AIDS (PHA) but risk is thought to be low. Methods To describe the state of knowledge about cancer patterns in Indian PHA, we reviewed reports from the international and Indian literature. Results As elsewhere, non-Hodgkin lymphomas dominate the profile of recognized cancers, with immunoblastic/large cell diffuse lymphoma being the most common type. Hodgkin lymphoma is proportionally increased, perhaps because survival with AIDS is truncated by fatal infections. In contrast, Kaposi sarcoma is rare, in association with an apparently low prevalence of Kaposi sarcoma-associated herpesvirus. If confirmed, the reasons for the low prevalence need to be understood. Cervical, anal, vulva/vaginal and penile cancers all appear to be increased in PHA, based on limited data. The association may be confounded by sexual behaviors that transmit both HIV and human papillomavirus. Head and neck tumor incidence may also be increased, an important concern since these tumors are among the most common in India. Based on limited evidence, the increase is at buccal/palatal sites, which are associated with tobacco and betel nut chewing rather than human papillomavirus. Conclusion With improving care of HIV and better management of infections, especially tuberculosis, the longer survival of PHA in India will likely increase the importance of cancer as a clinical problem in India. With the population's geographic and social diversity, India presents unique research opportunities that can be embedded in programs targeting HIV/AIDS and other public health priorities.

Abstract Background Helicobacter pylori (H. pylori) infection is ubiquitous in sub-Saharan Africa, but paradoxically gastric cancer is rare. Methods Sera collected during a household-based survey in rural Tanzania in 1985 were tested for anti-H. pylori IgG and IgG subclass antibodies by enzyme immunoassay. Odds ratios (OR) and confidence intervals (CI) of association of seropositivity with demographic variables were computed by logistic regression models. Results Of 788 participants, 513 were aged ≤17 years. H. pylori seropositivity increased from 76% at 0–4 years to 99% by ≥18 years of age. Seropositivity was associated with age (OR 11.5, 95% CI 4.2–31.4 for 10–17 vs. 0–4 years), higher birth-order (11.1; 3.6–34.1 for ≥3rd vs. 1st born), and having a seropositive next-older sibling (2.7; 0.9–8.3). Median values of IgG subclass were 7.2 for IgG1 and 2.0 for IgG2. The median IgG1/IgG2 ratio was 3.1 (IQR: 1.7–5.6), consistent with a Th2-dominant immune profile. Th2-dominant response was more frequent in children than adults (OR 2.4, 95% CI 1.3–4.4). Conclusion H. pylori seropositivity was highly prevalent in Tanzania and the immunological response was Th2-dominant. Th2-dominant immune response, possibly caused by concurrent bacterial or parasitic infections, could explain, in part, the lower risk of H. pylori-associated gastric cancer in Africa.

Background: To clarify which types of cancer result from AIDS, we compared the cancer experiences of people with AIDS with those of the general population by matching population-based cancer and AIDS registries in the USA and Puerto Rico.Methods: We used a probabilistic matching algorithm to compare names, birth dates, and, where available, social-security numbers of 98,336 people with AIDS and 1,125,098 people with cancer aged less than 70 years. We defined AIDS-related cancers as those with both significantly raised incidence post-AIDS and increasing prevalence from 5 years pre-AIDS to 2 years post-AIDS.Findings: Among people with AIDS, we found 7028 cases of Kaposi's sarcoma (KS), 1793 of non-Hodgkin lymphoma (NHL), and 712 other cases of histologically defined cancer. Incidence rates among people with AIDS were increased 310-fold for KS, 113-fold for NHL, and 1.9-fold (95% CI 1.5-2.3) for other cancers. Of 38 malignant disorders other than KS and NHL, only angiosarcoma (36.7-fold), Hodgkin's disease (7.6-fold), multiple myeloma (4.5-fold), brain cancer (3.5-fold), and seminoma (2.9-fold) were raised and increasing significantly (p<0.02) from the pre-AIDS to the post-AIDS period.Interpretation: Interpretation is complicated by screening and shared risk factors, such as sexual behaviour and cigarette smoking. However, our data indicate that AIDS leads to a significantly increased risk of Hodgkin's disease, multiple myeloma, brain cancer, and seminoma. Immunological failure to control herpes or other viral infections may contribute to these malignant diseases. [ABSTRACT FROM AUTHOR]