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C E Stevens

Publications and source records attributed to C E Stevens.

At least 55 records · Page 3Linked to original sources
PubMed1994

Progression of human immunodeficiency virus type 1 (HIV-1) infection among homosexual men in hepatitis B vaccine trial cohorts in Amsterdam, New York City, and San Francisco, 1978-1991.

The authors evaluated the progression of human immunodeficiency virus type 1 (HIV-1) disease from the date of seroconversion to the development of acquired immunodeficiency syndrome (AIDS) and death among 362 well-documented seroconverters. The participants were homosexual men in hepatitis B vaccine trials in Amsterdam (n = 74), New York City (n = 120), and San Francisco (n = 168). There were significant differences in the proportion of deaths, mean age at seroconversion, and mean age at AIDS diagnosis in the three cohorts, but no significant differences in the reported use of zidovudine and Pneumocystis carinii pneumonia prophylaxis. Overall progression rates did not differ significantly across the cohorts: the median time to the development of AIDS was 122 months, and the median time from the initial AIDS diagnosis to death was 20 months. Multivariate proportional hazards analysis of progression from HIV-1 seroconversion to the development of AIDS found faster progression after June 1989. Multivariate proportional hazards analysis of progression from AIDS to death found younger age at diagnosis, an initial diagnosis of Kaposi's sarcoma, and more recent calendar time to be associated with slower progression. Multivariate proportional hazards analysis of progression from HIV-1 seroconversion to death found older age at seroconversion to be associated with faster progression. The 1987 expansion of the AIDS case definition, improved diagnostic methods, and more conscientious care-seeking behaviors may have resulted in diagnosis of AIDS at an earlier stage of HIV-1 infection, which would shorten the apparent time from seroconversion to progression to AIDS. This would also tend to increase survival after an initial AIDS diagnosis, which was observed in the more recent calendar periods, although such increases could also result from improved treatments and prophylaxis for HIV-1 disease. The time from seroconversion to death, a period not influenced by variations in diagnosing AIDS, lengthened only slightly in recent years.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Epidemiologic background and long-term course of disease in human immunodeficiency virus type 1-infected blood donors identified before routine laboratory screening. Transfusion Safety Study Group.

BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1-infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high-risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Transfusion transmission of retroviruses: human T-lymphotropic virus types I and II compared with human immunodeficiency virus type 1.

BACKGROUND: The incidence of transfusion transmission of human T-lymphotropic virus type I (HTLV-I) and HTLV type II (HTLV-II) has not been compared directly or to that of human immunodeficiency virus type 1 (HIV-1). The effects of refrigerator storage of the blood component on infectivity of the viruses needs definition. STUDY DESIGN AND METHODS: The circumstances influencing the transmission of HTLV-I, HTLV-II, and HIV-1 via blood of donors whose sera were stored in a repository and who were retrospectively documented as having been infected at blood donation were examined. Confirmation and typing of anti-HTLV positivity in donors and recipients used polymerase chain reaction, supplemented by specific peptide testing. RESULTS: Overall, 27 percent (26/95) of the recipients of blood components from anti-HTLV-I- and -II-positive donors became infected (9 with HTLV-I and 17 with HTLV-II). No recipients of acellular blood components became infected with HTLV-I or -II. There was no probable transmission by components stored > 10 days. The rates of transmission for both viruses were similar: 0 to 5 days' storage, 17 (74%) of 23; 6 to 10 days, 8 (44%) of 18; and 11 to 14, 0 (0%) of 10 (trend, p = 0.0002). In comparison, 89 percent (112/126) of the recipients of anti-HIV-1-positive blood were infected regardless of component type, and no effect on transmission occurred with storage for < 26 days. CONCLUSION: Transfusion-transmitted HTLV-I and -II are similar. The data suggest that a donor's lymphocytes become noninfectious when they lose the ability to be activated or to proliferate.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Clinical manifestations of genital infection due to Chlamydia trachomatis in women: differences related to serovar.

The relationship between the infecting Chlamydia trachomatis serovar and the clinical manifestations of genital tract infection was evaluated in a study of 155 women attending a sexually transmitted diseases clinic; 99 women had lower genital tract infection and 56 had Chlamydia-associated pelvic inflammatory disease (PID). In the group with lower genital tract infection, women with serovar F differed from those with serovars of class B or C in that they exhibited fewer signs of cervical infection, including easily induced bleeding (P = .04), edema of the zone of cervical ectopy (P = .06), and colposcopic evidence of mucopurulent endocervical discharge (P = .007). Serovar F also produced fewer infections with inclusion counts of > or = 1,000 and fewer rectal infections (P = .04). There was no apparent association of any specific serovar with PID. Thus, in this population, serovar F was associated with fewer objective clinical manifestations of mucopurulent endocervical discharge, and the distribution of chlamydial serovars found in PID reflected that found in lower genital tract infection.

Adult↗
PubMed1994

The use of umbilical cord blood in mismatched related and unrelated hemopoietic stem cell transplantation.

Over the past 6 years, umbilical cord blood has emerged as an efficacious alternative source of hematopoietic stem cells in related bone marrow transplantation. These encouraging results led us to extend this technology to the mismatched related and unrelated settings in three high-risk leukemic children lacking a matched-related donor for transplantation. Two of the three children also lacked identifiable donors through the National Marrow Donor Program, while the third was in relapse and did not have time to wait for completion of a search. The first child was transplanted with haploidentical umbilical cord blood-derived mononuclear cells from his sister, while the remaining two children were transplanted with partially mismatched, unseparated, unrelated umbilical cord blood banked through the Placental Blood Project at the New York Blood Center. All three children demonstrated trilineage engraftment with donor cells within 6 weeks of transplantation. The patient transplanted with haploidentical marrow developed grade 2 graft vs. host disease (GVHD), which was controlled with steroid and anti-thymocyte globulin (ATG) therapy. One of the two patients grafted with unrelated umbilical cord blood developed mild grade 1 GVHD of the skin, which rapidly cleared with steroid therapy. One patient remains alive, in good health and disease-free 12 months from transplantation.

Acute Disease↗
PubMed1994

Unrelated placental blood for bone marrow reconstitution: organization of the placental blood program.

The usefulness of placental/umbilical cord blood as a source of stem cells for marrow reconstitution of HLA-matched siblings has now been extended to the unrelated-donor setting. The need for HLA-matched donor tissue makes it essential to have available a frozen inventory of ready-to-use placental blood units. The New York Blood Center's Placental Blood Project, designed to evaluate the practical feasibility of unrelated placental blood transplantation, consists of four basic modules: collection of placental blood, maternal samples and donor data, accession and testing for genetic and infectious disease markers, freezing placental blood units, and data organization and retrieval. Additional modules include a computerized HLA matching algorithm and organization of data about patients requiring transplantation, which may be best taken up by organ-sharing organizations in the future. In this report, we describe the organization and discuss the methods and overall experience after collecting the first 1,000 units and supplying the tissue for the first two unrelated-donor placental blood transplants.

Adult↗
PubMed1993

Effect of concurrent acute infection with hepatitis C virus on acute hepatitis B virus infection.

OBJECTIVE: To investigate the possible interference with acute hepatitis B virus infection by co-infection with hepatitis C virus. DESIGN: Analysis of stored sera collected for transfusion transmitted viruses study in 1970s. SETTING: Four major medical centres in the United States. PATIENTS: 12 recipients of blood infected with hepatitis B virus. MAIN OUTCOME MEASURES: In 1970s, presence of antibodies in hepatitis B virus and raised serum alanine aminotransferase concentration; detection of antibodies to hepatitis C virus with new enzyme linked immunoassays. RESULTS: Five of the 12 patients were coinfected with hepatitis C virus. Hepatitis B surface antigen was first detected at day 59 in patients infected with hepatitis B virus alone and at day 97 in those coinfected with hepatitis C virus (p = 0.01); median durations of antigenaemia were 83 and 21 days respectively (p = 0.05), and the antigen concentration was lower in the coinfected patients. Alanine aminotransferase patterns were uniphasic when hepatitis B virus infection occurred alone (range 479-2465 IU/l) and biphasic in patients with combined acute infection (no value > 380 IU/l; p = 0.0025). Four coinfected recipients developed chronic hepatitis C virus infection. The fifth patient was followed for only four months. CONCLUSIONS: Acute coinfection with hepatitis C virus and hepatitis B virus inhibits hepatitis B virus infection in humans, and onset of hepatitis B may reduce the severity of hepatitis C virus infection but not frequency of chronicity. Alanine aminotransferase concentration showed a biphasic pattern in dual infection.

Acute Disease↗
PubMed1993

Epidemiology of human immunodeficiency virus type 1 infection among homosexual men participating in hepatitis B vaccine trials in Amsterdam, New York City, and San Francisco, 1978-1990.

Homosexual/bisexual men from Amsterdam, The Netherlands, New York, New York, and San Francisco, California, were entered into trials of the efficacy of hepatitis B vaccine shortly before the acquired immunodeficiency syndrome (AIDS) epidemic was recognized (1978-1980). The authors analyzed data, including serial blood samples tested for antibody to human immunodeficiency virus type 1 (HIV-1) as well as demographic and behavioral information, to characterize the spread of HIV-1 infection within the cohorts. By the end of 1982, the cumulative incidence of HIV-1 infection within the cohorts. By the end of 1982, the cumulative incidence of HIV-1 infection was 7.5% in Amsterdam, 26.8% in New York City, and 42.6% in San Francisco. Covariate analysis showed that differences in sexual activity (number of male sexual partners) and correlates of sexual activity (age and hepatitis B incidence) accounted for the differences in incidence of HIV-1 infection between the New York City and San Francisco cohorts. These covariates did not explain the lower incidence in the Amsterdam cohort. In conclusion, significant differences were found in the spread of HIV-1 in cohorts of homosexual men in Amsterdam, New York City, and San Francisco. These dissimilarities were probably due to a combination of differences in sexual activity at the time the epidemic began and a later introduction of HIV-1 in Amsterdam.

Cohort Studies↗
PubMed1993

Development and application of in vitro models of hematopoiesis to drug development.

In vitro models of hematopoiesis are used increasingly in investigative hematopathology. Such models complement in vivo animal testing and have been shown to be predictive for hematotoxicity associated with anticancer and antiviral agents in humans. In vitro models of hematopoiesis consist of short-term cloning assays for various hematopoietic progenitor cells and long-term functional assays for the marrow hematopoietic microenvironment. In our laboratories, the cloning assays have been used as investigative tools to study the pathogenetic mechanisms of drug-induced blood disorders and as screening systems to investigate the possible hematotoxic potential of candidate drugs in various animal species. Data in support of these applications are presented in this paper.

Animals↗
PubMed1992

A cohort study of the risk of cervical intraepithelial neoplasia grade 2 or 3 in relation to papillomavirus infection.

BACKGROUND: Human papillomavirus (HPV) has been associated with cervical intraepithelial neoplasia, but the temporal relation between the infection and the neoplasia remains unclear, as does the relative importance of the specific type of HPV, other sexually transmitted diseases, and other risk factors. METHODS: We studied prospectively a cohort of 241 women who presented for evaluation of sexually transmitted disease and had negative cervical cytologic tests. The women were followed every four months with cytologic and colposcopic examinations of the uterine cervix and tests for HPV DNA and other sexually transmitted diseases. RESULTS: Cervical intraepithelial neoplasia grade 2 or 3 was confirmed by biopsy in 28 women. On the basis of survival analysis, the cumulative incidence of cervical intraepithelial neoplasia at two years was 28 percent among women with a positive test for HPV and 3 percent among those without detectable HPV DNA: The risk was highest among those with HPV type 16 or 18 infection (adjusted relative risk as compared with that in women without HPV infection, 11; 95 percent confidence interval, 4.6 to 26; attributable risk, 52 percent). All 24 cases of cervical intraepithelial neoplasia grade 2 or 3 among HPV-positive women were detected within 24 months after the first positive test for HPV. After adjustment for the presence of HPV infection, the development of cervical intraepithelial neoplasia was also associated with younger age at first intercourse, the presence of serum antibodies to Chlamydia trachomatis, the presence of serum antibodies to cytomegalovirus, and cervical infection with Neisseria gonorrhoeae. CONCLUSIONS: Cervical intraepithelial neoplasia is a common and apparently early manifestation of cervical infection by HPV, particularly types 16 and 18.

Adolescent↗
PubMed1992

Mortality trends in a cohort of homosexual men in New York City, 1978-1988.

Trends in mortality related to infection by human immunodeficiency virus type 1 (HIV-1) and to other causes were examined from 1978 to 1988 in a cohort of 8,906 homosexual men who participated in studies of hepatitis B virus infection in the late 1970s in New York City. HIV-related mortality rates increased from 1 per 10,000 person-years in 1980 to 181 per 10,000 person-years in 1986, followed by a plateau from 1986 to 1988. The standardized mortality ratio among white men in the cohort was 3.7 (95% confidence interval (Cl) 3.4-3.9) as compared with white men from across the United States. Higher HIV-related mortality rates were associated with a higher number of sexual partners, a history of gonorrhea and/or syphilis, and serologic markers of infection with hepatitis B virus. After adjustment for demographics and sexual behaviors, the relative risk of mortality for Hispanic men as compared with white men was 1.5 (95% Cl 1.1-1.9). This study illustrates the large excess in mortality among homosexual men over the last decade, with the excess accounted for by deaths from HIV-related diseases. The recent plateau in mortality may be due to the effect of new treatments and/or the decline in new HIV-1 infections among homosexual men. The excess in HIV-related mortality among Hispanic homosexual men was not explained by differences in demographics and factors associated with the sexual transmission of HIV-1.

Adult↗
PubMed1992

Underdiagnosis of genital herpes by current clinical and viral-isolation procedures.

BACKGROUND: The current clinical strategy for diagnosing genital herpes simplex virus (HSV) infection in women relies on clinical findings plus the selective use of viral culture. The effectiveness of this approach for identifying women with genital herpes is unknown. METHODS: We performed physical examinations, colposcopy, Pap smears, viral cultures, and HSV type-specific serologic assays of 779 randomly selected women attending a sexually transmitted disease clinic. RESULTS: Evidence of HSV type 2 infection was detected in 363 women (47 percent), and 9 others (1 percent) had positive cultures indicative of urogenital or anal infection with HSV type 1. Of these 372 women, only 82 (22 percent) had symptoms. Fourteen women (4 percent) had viral shedding without symptoms, 60 (16 percent) had formerly had symptomatic episodes, and 216 (58 percent) had antibodies to HSV-2 with neither viral shedding nor a history of clinical episodes. Characteristic ulcerations of the external genitalia were present in only two thirds of the 66 women with positive HSV cultures; the others had atypical genital lesions or asymptomatic viral shedding. Isolation of HSV from a genitourinary tract specimen was the most sensitive (77 percent) test for confirming a first episode of infection. The detection of HSV-2-specific antibodies was the most sensitive (97 percent) way to confirm symptomatic reactivations of HSV-2 infection. HSV-2 serologic testing also identified the 290 women with asymptomatic HSV-2 infections (37 percent), including 14 (5 percent) who were shedding virus asymptomatically on the day of the examination. CONCLUSIONS: The current strategy for diagnosing genital HSV infection in women misses many cases. Newly developed type-specific serologic methods can identify women with recurrent genital HSV-2 infection, as well as those with unrecognized or subclinical infection.

Adolescent↗
PubMed1992

Effect of duration of hepatitis B virus infection on the association between human immunodeficiency virus type-1 and hepatitis B viral replication.

This study examined the effect of duration of hepatitis B virus infection on the association between human immunodeficiency virus type-1 infection and hepatitis B viral replication. Twenty-five chronic HBsAg carriers were studied. Presence of hepatitis B virus DNA and expression of HBeAg were more frequent among 20 chronic HBsAg carriers positive for human immunodeficiency virus type-1 antibody compared with five chronic HBsAg carriers negative for human immunodeficiency virus type-1 antibody, but the associations were not statistically significant. Hepatitis B virus DNA and HBeAg were inversely related to duration of hepatitis B virus infection (p less than 0.001). Stratifying for duration of hepatitis B virus infection, the presence of viral replication was similar among patients negative and positive for antibody to human immunodeficiency virus type-1. Hepatitis B virus DNA levels did not increase with the decline of cellular immunity over time. In conclusion, hepatitis B virus replication among chronic carriers may be a function of duration of hepatitis B virus infection rather than of an effect of human immunodeficiency virus type-1.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Sialidases (neuraminidases) in bacterial vaginosis and bacterial vaginosis-associated microflora.

Bacterial vaginosis, Prevotella species, and Bacteroides species have been associated with prematurity and upper genital tract infection. Prevotella (Bacteroides) species and Bacteroides fragilis have also been associated with preterm birth. However, the mechanism by which lower genital tract infection causes upper genital tract disease remains poorly understood. Sialidases (neuraminidases) are enzymes which enhance the ability of microorganisms to invade and destroy tissue. Elevated levels of sialidase activity were detected in 42 (84%) of 50 vaginal fluid specimens from women with bacterial vaginosis and none of 19 vaginal fluids from women without bacterial vaginosis (P less than 0.001). Vaginal fluid from women with bacterial vaginosis had a median specific activity of 9.8 U compared to 2.5 U of sialidase in women without bacterial vaginosis (P less than 0.001). In order to determine the probable source of sialidases in vaginal fluid, the microorganisms recovered from women with bacterial vaginosis before and after treatment were assayed. Of 28 specimens from women with bacterial vaginosis, 27 (96%) yielded sialidase-positive bacteria, at a median concentration of 10(6.5) CFU/ml of vaginal fluid. Prevotella and Bacteroides species accounted for the sialidase activity in 26 of the vaginal fluids, and Gardnerella vaginalis accounted for the sialidase activity in the remaining fluid. After treatment, sialidase was detected in the vaginal fluid of 1 (5%) of 22 women who responded to therapy and in all of 6 women for whom therapy failed. These data suggest that vaginal fluid sialidase is highly correlated with bacterial vaginosis and that the probable sources for this enzyme activity are the Bacteroides and Prevotella species present in the vagina.

Adolescent↗
PubMed1992

Prospects for control of hepatitis B virus infection: implications of childhood vaccination and long-term protection.

Hepatitis B vaccine has been recommended for high-risk individuals in the United States for more than a decade. This targeted strategy, however, has failed to control hepatitis B virus (HBV) infection. Universal immunization is being considered as an alternative approach, in particular the inclusion of hepatitis B vaccine with routine childhood vaccinations. Data presented herein demonstrate a high degree of efficacy for hepatitis vaccine with hepatitis B immune globulin in preventing perinatal HBV infection in newborns. Immune response to vaccine was dependent in part on the dose administered, with some enhancement of response if the infant was older at the time of initial injection or if the booster dose was given later. Long-term follow-up showed persistence of vaccine-induced antibody for 5 to 10 years in 90% of immunized infants and adults. Only 3% to 5% of these high-risk individuals had serologic evidence of an HBV infection. None of the infections had been symptomatic and none resulted in a chronic HBV carrier state. Thus, immune responses and efficacy of hepatitis B vaccine in infants were excellent, and immunity and protection against clinically significant HBV infection persisted for at least 5 to 10 years, features essential to success of a program of universal childhood immunization against HBV.

Child↗
PubMed1991

Hepatitis C virus infection in post-transfusion hepatitis. An analysis with first- and second-generation assays.

BACKGROUND: The causes of post-transfusion non-A, non-B hepatitis are still not fully defined, nor is it clear how accurate the tests are that are used to screen blood donors for hepatitis C virus (HCV) and to diagnose post-transfusion hepatitis caused by infected blood. METHODS: We used two first-generation enzyme-linked immunoassays (EIAs) and one second-generation immunoassay to test for anti-HCV antibodies in serum samples collected between 1976 and 1979 in the Transfusion-Transmitted Viruses Study (from 1247 patients who underwent transfusion and 1235 matched control subjects who did not receive transfusions). We tested serum collected before and after infection from the patients in whom non-A, non-B hepatitis developed, serum from their blood donors, and serum from 41 of the control subjects who had hepatitis unrelated to transfusion. RESULTS: Of the 115 patients in whom post-transfusion non-A, non-B hepatitis developed, the initial serum samples of 111 were anti-HCV-negative; after hepatitis developed in these 111 patients, the first-generation EIAs detected anti-HCV in 51 (46 percent), and the second-generation assay detected anti-HCV in an additional 16 (14 percent), for a total of 60 percent. Of 40 controls, 37 were anti-HCV-negative initially, and none seroconverted after hepatitis developed. If the 3 percent rate of non-A, non-B, non-C hepatitis among the controls (37 of 1235) was applied to the 1247 transfusion recipients, only 74 of the 111 cases of hepatitis were attributable to the transfusion. Thus, 91 percent (67 of 74) of the cases of post-transfusion hepatitis were caused by HCV. Of the 99 donors, 60 were HCV-positive (9 on second-generation tests only) and 39 were not. CONCLUSIONS: Nearly all cases of non-A, non-B post-transfusion hepatitis are caused by HCV. Screening with a second-generation assay improves the rate of detection of HCV infection in patients with post-transfusion hepatitis and in blood donors. The use of this test showed a 3.6 percent risk of non-A, non-B, non-C hepatitis, which was not significantly different from the rate in the controls (3.0 percent).

Blood Donors↗