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Dive into the research topics where Stephen A. Spector is active.

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Featured researches published by Stephen A. Spector.


Obstetrical & Gynecological Survey | 1997

Maternal Viral Load, Zidovudine Treatment, and the Risk of Transmission of Human Immunodeficiency Virus Type 1 from Mother to Infant

Rhoda S. Sperling; David Shapiro; Robert W. Coombs; John A. Todd; Steven Herman; George McSherry; Mary Jo O'Sullivan; Russell B. Van Dyke; Eleanor Jimenez; Christine Rouzioux; Patricia M. Flynn; John L. Sullivan; Stephen A. Spector; Clemente Diaz; James F. Rooney; James Balsley; Richard D. Gelber; Edward M. Connor

BACKGROUND AND METHODS A placebo-controlled trial has shown that treatment with zidovudine reduces the rate at which human immunodeficiency virus type 1 (HIV-1) is transmitted from mother to infant. We present data from that trial showing the number of infected infants at 18 months of age and the relation between the maternal viral load, the risk of HIV-1 transmission, and the efficacy of zidovudine treatment. Viral cultures were obtained, and HIV-1 RNA was measured by two assays in samples of maternal blood obtained at study entry and at delivery. RESULTS In 402 mother-infant pairs, the rate of transmission of HIV-1 was 7.6 percent (95 percent confidence interval, 4.3 to 12.3 percent) with zidovudine treatment and 22.6 percent (95 percent confidence interval, 17.0 to 29.0 percent) with placebo (P<0.001). In the placebo group, a large viral burden at entry or delivery or a positive culture was associated with an increased risk of transmission (the transmission rate was greater than 40 percent in the highest quartile of the RNA level). In both groups, transmission occurred at a wide range of maternal plasma HIV-1 RNA levels. Zidovudine reduced plasma RNA levels somewhat (median reduction, 0.24 log). Zidovudine was effective regardless of the HIV-1 RNA level or the CD4+ count at entry. In the zidovudine group, however, after we adjusted for the base-line HIV-1 RNA level and CD4+ count, the reduction in viral RNA from base line to delivery was not significantly associated with the risk of transmission of HIV-1. CONCLUSIONS A high maternal plasma concentration of virus is a risk factor for the transmission of HIV-1 from an untreated mother to her infant. The reduction in such transmission after zidovudine treatment is only partly explained by the reduction in plasma levels of viral RNA. To prevent HIV-1 transmission, initiating maternal treatment with zidovudine is recommended regardless of the plasma level of HIV-1 RNA or the CD4+ count.


The New England Journal of Medicine | 1996

Maternal viral load, zidovudine treatment, and the risk of transmission of human immunodeficiency virus type 1 from mother to infant

Rhoda S. Sperling; David Shapiro; Robert W. Coombs; John Todd; Steven Herman; George McSherry; Mary Jo O'Sullivan; Russell B. Van Dyke; Eleanor Jimenez; Christine Rouzioux; Patricia M. Flynn; John L. Sullivan; Stephen A. Spector; Clemente Diaz; James F. Rooney; James Balsley; Richard D. Gelber; Edward M. Connor

BACKGROUND AND METHODS A placebo-controlled trial has shown that treatment with zidovudine reduces the rate at which human immunodeficiency virus type 1 (HIV-1) is transmitted from mother to infant. We present data from that trial showing the number of infected infants at 18 months of age and the relation between the maternal viral load, the risk of HIV-1 transmission, and the efficacy of zidovudine treatment. Viral cultures were obtained, and HIV-1 RNA was measured by two assays in samples of maternal blood obtained at study entry and at delivery. RESULTS In 402 mother-infant pairs, the rate of transmission of HIV-1 was 7.6 percent (95 percent confidence interval, 4.3 to 12.3 percent) with zidovudine treatment and 22.6 percent (95 percent confidence interval, 17.0 to 29.0 percent) with placebo (P<0.001). In the placebo group, a large viral burden at entry or delivery or a positive culture was associated with an increased risk of transmission (the transmission rate was greater than 40 percent in the highest quartile of the RNA level). In both groups, transmission occurred at a wide range of maternal plasma HIV-1 RNA levels. Zidovudine reduced plasma RNA levels somewhat (median reduction, 0.24 log). Zidovudine was effective regardless of the HIV-1 RNA level or the CD4+ count at entry. In the zidovudine group, however, after we adjusted for the base-line HIV-1 RNA level and CD4+ count, the reduction in viral RNA from base line to delivery was not significantly associated with the risk of transmission of HIV-1. CONCLUSIONS A high maternal plasma concentration of virus is a risk factor for the transmission of HIV-1 from an untreated mother to her infant. The reduction in such transmission after zidovudine treatment is only partly explained by the reduction in plasma levels of viral RNA. To prevent HIV-1 transmission, initiating maternal treatment with zidovudine is recommended regardless of the plasma level of HIV-1 RNA or the CD4+ count.


Annals of Internal Medicine | 1990

The Safety and Efficacy of Zidovudine (AZT) in the Treatment of Subjects with Mildly Symptomatic Human Immunodeficiency Virus Type 1 (HIV) Infection: A Double-Blind, Placebo-Controlled Trial

Margaret A. Fischl; Douglas D. Richman; Nellie I. Hansen; Ann C. Collier; John T. Carey; Michael F. Para; W. David Hardy; Raphael Dolin; William G. Powderly; J. Davis Allan; Brian Wong; Thomas C. Merigan; Vincent McAuliffe; Newton E. Hyslop; Frank S. Rhame; Henry H. Balfour; Stephen A. Spector; Paul A. Volberding; Carla Pettinelli; James Anderson

OBJECTIVE To evaluate the efficacy and safety of zidovudine early in the treatment of human immunodeficiency virus type 1 (HIV) infection. DESIGN A double-blind, randomized, placebo-controlled trial with subject stratification by pretreatment CD4 T lymphocyte counts. SETTING Multicenter trial at AIDS Clinical Trial units. SUBJECTS Seven hundred eleven subjects with mildly symptomatic HIV infection. INTERVENTION Three hundred fifty-one subjects were assigned to placebo and 360 to zidovudine, 200 mg orally every 4 hours. The median duration of follow-up was 11 months. MEASUREMENTS AND MAIN RESULTS Fifty-one subjects developed the acquired immunodeficiency syndrome (AIDS), advanced AIDS-related complex, or death as a first critical event. For the stratum of subjects with more than 200 but less than 500 CD4 T lymphocytes/mm3 before treatment, 34 events occurred in placebo recipients and 12 in zidovudine recipients (P = 0.0002; relative risk [RR] estimate, 3.23 [95% CI, 1.67 to 6.24]). For the stratum of subjects with 500 to 799 CD4 T lymphocytes/mm3 before treatment, 2 events occurred in placebo recipients and 3 in zidovudine recipients. Candidiasis at study entry independently increased the risk for having an event (P = 0.005; RR estimate, 2.3 [95% CI, 1.29 to 4.12]); HIV antigenemia at study entry also increased this risk (P = 0.01; RR estimate, 2.1 [95% CI, 1.2 to 3.8]). Significant differences between the treatment groups in CD4 T-lymphocyte counts occurred in subjects with more than 200 but less than 500 CD4 T lymphocytes/mm3 after 4 weeks of therapy (P = 0.002). Differences persisted through week 52. Less prominent changes occurred in subjects with 500 or more CD4 T lymphocytes/mm3. Serum levels of HIV antigen decreased significantly in zidovudine recipients. Serious anemia and neutropenia occurred in 5% and 4% of zidovudine recipients, respectively, and in 0% and 1% of placebo recipients, respectively. CONCLUSION Zidovudine delayed progression of HIV disease and produced little toxicity in subjects with mildly symptomatic HIV disease and less than 500 CD4 T lymphocytes/mm3.


Annals of Internal Medicine | 1987

Evidence for Early Central Nervous System Involvement in the Acquired Immunodeficiency Syndrome (AIDS) and Other Human Immunodeficiency Virus (HIV) Infections: Studies with Neuropsychologic Testing and Magnetic Resonance Imaging

Igor Grant; J. Hampton Atkinson; John R. Hesselink; Caroline J. Kennedy; Douglas D. Richman; Stephen A. Spector; J. Allen McCutchan

Although a high prevalence of central nervous system disease is seen in persons with the acquired immunodeficiency syndrome (AIDS), the natural history of brain involvement with human immunodeficiency virus (HIV) remains poorly understood. Neuropsychologic evaluations of 55 ambulatory homosexual men revealed abnormalities in 13 of 15 with AIDS, 7 of 13 [corrected] with AIDS-related complex, 7 of 16 [corrected] with HIV-seropositivity only, and 1 of 11 with HIV-seronegativity. Common neuropsychologic problems included impaired abstracting ability, learning difficulties, and slowed speed of information processing. Magnetic resonance imaging had abnormal findings in 9 of 13 patients with AIDS and 5 of 10 patients with AIDS-related complex who were available for scans. The commonest abnormalities were sulcal and ventricular enlargement and bilateral patchy areas of high signal intensity in the white matter. We postulate that central nervous system involvement by HIV may begin early in the course of AIDS and cause mild cognitive deficits in otherwise asymptomatic persons.


Nature | 2013

Identification of a candidate therapeutic autophagy-inducing peptide

Sanae Shoji-Kawata; Rhea Sumpter; Matthew J Leveno; Grant R. Campbell; Zhongju Zou; Lisa N. Kinch; Angela D. Wilkins; Qihua Sun; Kathrin Pallauf; Donna A. MacDuff; Carlos Huerta; Herbert W. Virgin; J. Bernd Helms; Ruud Eerland; Sharon A. Tooze; Ramnik J. Xavier; Deborah J. Lenschow; Ai Yamamoto; David S. King; Olivier Lichtarge; Nick V. Grishin; Stephen A. Spector; Dora Kaloyanova; Beth Levine

The lysosomal degradation pathway of autophagy has a crucial role in defence against infection, neurodegenerative disorders, cancer and ageing. Accordingly, agents that induce autophagy may have broad therapeutic applications. One approach to developing such agents is to exploit autophagy manipulation strategies used by microbial virulence factors. Here we show that a peptide, Tat–beclin 1—derived from a region of the autophagy protein, beclin 1, which binds human immunodeficiency virus (HIV)-1 Nef—is a potent inducer of autophagy, and interacts with a newly identified negative regulator of autophagy, GAPR-1 (also called GLIPR2). Tat–beclin 1 decreases the accumulation of polyglutamine expansion protein aggregates and the replication of several pathogens (including HIV-1) in vitro, and reduces mortality in mice infected with chikungunya or West Nile virus. Thus, through the characterization of a domain of beclin 1 that interacts with HIV-1 Nef, we have developed an autophagy-inducing peptide that has potential efficacy in the treatment of human diseases.


The New England Journal of Medicine | 1995

A Randomized Trial Comparing Fluconazole with Clotrimazole Troches for the Prevention of Fungal Infections in Patients with Advanced Human Immunodeficiency Virus Infection

William G. Powderly; Dianne M. Finkelstein; Judith Feinberg; Peter Frame; Weili He; Charles van der Horst; Susan L. Koletar; M. Elaine Eyster; John T. Carey; Hetty Waskin; Thomas M. Hooton; Newton E. Hyslop; Stephen A. Spector; Samuel A. Bozzette

Background Cryptococcal meningitis and other serious fungal infections are common complications in patients infected with the human immunodeficiency virus (HIV). Fluconazole is effective for long-term suppression of many fungal infections, but its effectiveness as primary prophylaxis had not been adequately evaluated. Methods We conducted a prospective, randomized trial that compared fluconazole (200 mg per day) with clotrimazole troches (10 mg taken five times daily) in patients who were also participating in a randomized trial of primary prophylaxis for Pneumocystis carinii pneumonia. Results After a median follow-up of 35 months, invasive fungal infections had developed in 4.1 percent of the patients in the fluconazole group (9 of 217) and in 10.9 percent of those in the clotrimazole group (23 of 211; relative hazard, as adjusted for the CD4+ count, 3.3; 95 percent confidence interval, 1.5 to 7.6). Of the 32 invasive fungal infections, 17 were cryptococcosis (2 in the fluconazole group and 15 in the cl...


The New England Journal of Medicine | 1995

A Randomized Trial of Three Antipneumocystis Agents in Patients with Advanced Human Immunodeficiency Virus Infection

Samuel A. Bozzette; Dianne M. Finkelstein; Stephen A. Spector; Peter Frame; William G. Powderly; Weili He; Lucinda Phillips; Donald E. Craven; Charles van der Horst; Judith Feinberg

BACKGROUND We evaluated the effectiveness of three treatment strategies for the prevention of a first episode of Pneumocystis carinii pneumonia in patients infected with the human immunodeficiency virus (HIV). METHODS In an open-label trial, 843 patients with HIV infection and fewer than 200 CD4+ cells per cubic millimeter received zidovudine plus one of three randomly assigned prophylactic agents, beginning with trimethoprim-sulfamethoxazole, dapsone, or aerosolized pentamidine and followed by a defined sequence of other drugs to be used in cases of intolerance. RESULTS The estimated 36-month cumulative risks of P. carinii pneumonia were 18 percent, 17 percent, and 21 percent in the trimethoprim-sulfamethoxazole, dapsone, and aerosolized-pentamidine groups, respectively (P = 0.22). The difference in risk among treatment strategies was negligible in patients entering the study with 100 or more CD4+ lymphocytes per cubic millimeter. In those entering with fewer than 100 CD4+ cells per cubic millimeter, the risk was 33 percent with aerosolized pentamidine, as compared with 19 percent with trimethoprim-sulfamethoxazole and 22 percent with dapsone (P = 0.04). The lowest failure rates occurred in patients receiving trimethoprim-sulfamethoxazole, and failures were more common with 50 mg of dapsone than with 100 mg. Toxoplasmosis developed in less than 3 percent of patients. Of the patients assigned to the two systemic therapies, only 23 percent were receiving their assigned drug and dose when they completed the study. The median survival was approximately 39 months in all three groups, and the mortality attributable to P. carinii pneumonia was only 1 percent. CONCLUSIONS In patients with advanced HIV infection, the three treatment strategies we examined have similar effectiveness in preventing P. carinii pneumonia. Strategies that start with trimethoprim-sulfamethoxazole or with high-dose dapsone, rather than aerosolized pentamidine, are superior in patients with fewer than 100 CD4+ lymphocytes per cubic millimeter.


The New England Journal of Medicine | 1996

Oral Ganciclovir for the Prevention of Cytomegalovirus Disease in Persons with AIDS

Stephen A. Spector; George F. McKinley; Jacob Lalezari; Tobias Samo; Robert Andruczk; Stephen E. Follansbee; Paula D. Sparti; Diane V. Havlir; Gail Simpson; William Buhles; Rodney Wong; Mary Jean Stempien

BACKGROUND In the advanced stages of the acquired immunodeficiency syndrome (AIDS), cytomegalovirus (CMV) disease, particularly vision-damaging retinitis due to CMV is common. We evaluated prophylactic treatment with orally administered ganciclovir as a way to prevent CMV disease. METHODS We conducted a prospective, randomized, double-blind, placebo-controlled study of CMV infected persons with AIDS with either CD4+ lymphocyte counts of < or = 50 per cubic millimeter or counts of < or = 100 per cubic millimeter in those with a history of an AIDS defining opportunistic infection. Patients were randomly assigned, in a 2:1 ratio, to receive either oral ganciclovir (1000 mg three times daily) or placebo. RESULTS The study was stopped after a median 367 days of follow-up. In an intention-to-treat analysis, the twelve month cumulative rates of confirmed CMV disease were 26 percent in the placebo group (n = 239) and 14 percent in the ganciclovir group (n = 486), representing an overall reduction in risk of 49 percent in the ganciclovir group (P < 0.001). The incidence of CMV retinitis after 12 months was 24 percent in the placebo group and 12 percent in the ganciclovir group (P < 0.0001). The prevalence of CMV-positive urine cultures at base line was 42 percent; after two months it was 43 percent in the placebo group and 10 percent in the ganciclovir group (P < 0.0001). The one year mortality rate was 26 percent in the placebo group and 21 percent in the ganciclovir group (P = 0.14). Therapy with granulocyte colony stimulating factor was more frequent in the ganciclovir group (24 percent) than in the placebo group (9 percent). CONCLUSIONS In persons with advanced AIDS, phophylactic oral ganciclovir significantly reduces the risk of CMV disease.


The Journal of Infectious Diseases | 1997

Ganciclovir Treatment of Symptomatic Congenital Cytomegalovirus Infection: Results of a Phase II Study

Richard J. Whitley; Gretchen A. Cloud; William C. Gruber; Gregory A. Storch; Gail J. Demmler; Richard F. Jacobs; Wayne M. Dankner; Stephen A. Spector; Stuart E. Starr; Robert F. Pass; Sergio Stagno; William J. Britt; Charles A. Alford; Seng-jaw Soong; Xiao-Jian Zhou; Lanette Sherrill; Jan M. FitzGerald; Jean-Pierre Sommadossi

Congenital cytomegalovirus (CMV) infection occurs in approximately 1% of newborns in the United States. A phase II evaluation was done of ganciclovir for the treatment of symptomatic congenital CMV infection. Daily doses of 8 or 12 mg/kg were administered in divided doses at 12-h intervals for 6 weeks. Clinical and laboratory evaluations sought evidence of toxicity, quantitative virologic responses in urine, plasma drug concentrations, and clinical outcome. A total of 14 and 28 babies received 8 and 12 mg/kg/day, respectively. Five additional babies received ganciclovir on a compassionate plea basis. Significant laboratory abnormalities included thrombocytopenia (< or = 50,000/mm3) in 37 babies and absolute neutropenia (< or = 500 mm3) in 29 babies. Quantitative excretion of CMV in the urine decreased; however, after cessation of therapy, viruria returned to near pretreatment levels. Hearing improvement or stabilization occurred in 5 (16%) of 30 babies at 6 months or later, indicating efficacy.


The Journal of Infectious Diseases | 1997

High-Level Resistance of Cytomegalovirus to Ganciclovir Is Associated with Alterations in Both the UL97 and DNA Polymerase Genes

Irene L. Smith; Julie M. Cherrington; Rhett E. Jiles; Michael D. Fuller; William R. Freeman; Stephen A. Spector

Mutations in both the viral phosphotransferase gene, UL97, and the DNA polymerase gene, UL54, have been shown to confer ganciclovir resistance to cytomegalovirus (CMV). Moreover, UL54 alterations have been associated with in vitro cross-resistance of CMV to cidofovir. To investigate the relative significance of UL97 versus UL54 alterations in conferring antiviral resistance, phenotypic and genotypic characterization of 28 ganciclovir-resistant clinical CMV isolates was undertaken. Isolates were either low-level ganciclovir-resistant, which have ganciclovir ID50 values > or =8 microM and <30 microM and sensitivity to cidofovir, or high-level ganciclovir-resistant, which have ganciclovir ID50 values > or =30 microM and cross-resistance to cidofovir. Low-level ganciclovir-resistant isolates were associated with UL97 alterations and short periods of ganciclovir treatment, while high-level ganciclovir-resistant isolates were associated with both UL97 and polymerase alterations and were cultured after extended ganciclovir therapy.

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Kumud K. Singh

University of California

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Ram Yogev

Northwestern University

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George K. Siberry

National Institutes of Health

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