Soft tissue sarcomas: preoperative versus postoperative radiotherapy.

External beam radiation may be given either before or after excision of a primary soft tissue sarcoma. This study was undertaken to determine whether or not the timing of radiotherapy was associated with any difference in either local control, survival, or incidence of complications. The files of 112 patients with a primary, nonmetastatic, extremity soft tissue sarcoma, treated with limb salvage surgery and irradiation were evaluated.

Multidrug-resistant human immunodeficiency virus type 1 strains resulting from combination antiretroviral therapy.

Multidrug-resistant human immunodeficiency virus type 1 (HIV-1) strains with reverse transcriptase (RT) mutations at codons A62-->V, V75-->I, F77-->L, F116-->Y, and Q151-->M have been reported in patients receiving combination therapy with zidovudine (AZT) and didanosine (ddI). Infectious clones with each mutation alone, all five mutations together, and various combinations of mutations were created by site-directed mutagenesis. Mutation Q151-->M conferred partial resistance to AZT, ddI, zalcitibine, and stavudine, whereas a combination of four mutations conferred increased resistance to AZT, ddI, zalcitibine, and stavudine.

Drug resistance and heterogeneous long-term virologic responses of human immunodeficiency virus type 1-infected subjects to zidovudine and didanosine combination therapy. The AIDS Clinical Trials Group 143 Virology Team.

Plasma human immunodeficiency virus (HIV) type 1 RNA levels, CD4 lymphocyte changes, and drug resistance were studied in HIV-infected patients with 200-500 CD4 lymphocytes/microL who received zidovudine and didanosine combination therapy for 2 years. Among 35 patients, 10 had sustained and 16 had transient > 10-fold reductions in HIV RNA: 9 did not have 10-fold HIV RNA reductions. Only patients with sustained HIV suppression maintained increased CD4 cell counts for 2 years (370 to 501 cells/microL; P = .

Detection of drug resistance mutations in the human immunodeficiency virus type 1 (HIV-1) pol gene: differences in semen and blood HIV-1 RNA and proviral DNA.

Different tissues or body fluids in which human immunodeficiency virus type 1 (HIV-1) can reside may contain viruses with distinct characteristics. Sixteen HIV-1-infected patients receiving zidovudine or didanosine were studied cross-sectionally and 1 patient who switched from zidovudine to didanosine was followed sequentially to determine if drug resistance mutations within the HIV-1 pol gene at codons 74 and 215 differed depending on the compartment from which the gene was isolated (plasma, seminal fluid, peripheral blood mononuclear cells, or seminal nonspermatozoal mononuclear cells). Cell-free virus in plasma and semen developed detectable mutations first, followed by proviral DNA in seminal nonspermatozoal and peripheral blood mononuclear cells.

Double-blind trial of fluoxetine: chronic daily headache and migraine.

This study is the first double-blind placebo-controlled trial of fluoxetine for chronic daily headache (CDH) and migraine. After a one month single-blind baseline on placebo, subjects with CDH (n = 64) and migraine (n = 58) were randomly assigned to a three month trial of fluoxetine (20 mg) or an identical placebo. Fluoxetine and placebo were increased to 40 mg in the second month, depending on patient response.

Public health. Eyes on the prize.

Public health has been reborn in the past ten years, with the development of a broad-based movement representing a range of perspectives. But is the public health movement losing sight of its origins and objectives? Maggie Winters, projects manager of the Public Health Alliance, to which the HVA is affiliated, puts the case for a radical public health critique.

Didanosine resistance in HIV-infected patients switched from zidovudine to didanosine monotherapy.

Objective: To determine the frequency and pattern of development of specific drug resistance mutations for human immunodeficiency virus (HIV) reverse transcriptase in patients switched from zidovudine to didanosine therapy and to examine the relation of the didanosine resistance mutation at codon 74 of the HIV reverse-transcriptase gene to CD4+ T-cell changes and virus burden.

Design: Retrospective analysis of all patients enrolled at Stanford University in protocols where patients were switched from zidovudine to didanosine monotherapy.

Setting: A university hospital.

HIV-1 syncytium-inducing phenotype, virus burden, codon 215 reverse transcriptase mutation and CD4 cell decline in zidovudine-treated patients.

The variable rate of disease progression in HIV-1-infected patients treated with zidovudine may be related to certain viral characteristics, such as, antiviral drug resistance, virus burden, and viral syncytium-inducing (SI) capacity. Thirty-two HIV-1-infected patients treated with zidovudine (mean of 34 months) were studied to determine the relationship of SI phenotype and the codon 215 pol gene mutation (a marker of zidovudine resistance) to virus burden and CD4 cell decline. Patients with SI strains and the codon 215 mutation in their proviral DNA had a 54% decline in CD4 cells and a virus burden of 21,480 proviral DNA copies/10(6) CD4 cells.

Combination therapy with zidovudine and didanosine selects for drug-resistant human immunodeficiency virus type 1 strains with unique patterns of pol gene mutations.

Drug resistance conferred by specific human immunodeficiency virus type 1 (HIV-1) pol gene mutations has been associated with clinical progression in HIV-infected patients receiving anti-retroviral therapy. This study examined drug susceptibilities and pol mutations of HIV-1 strains from patients treated for 1 year with zidovudine, didanosine (ddI), or zidovudine and ddI. Ten (42%) of 24 patients receiving combination therapy versus 8/26 (31%) receiving only zidovudine had HIV-1 strains with phenotypic zidovudine resistance or a zidovudine resistance pol mutation at codon 215 (P = .

Diurnal and short-term stability of HIV virus load as measured by gene amplification.

To determine whether human immunodeficiency virus (HIV) viral load has short term stability, eight clinically stable subjects infected with HIV and having CD4 counts ranging between 10-600/mm3, had blood samples taken at 0800 and 1700 on 3 consecutive days and then weekly at 0800 for 1 month (8-10 observations/subject). Plasma HIV RNA, peripheral blood mononuclear cell (PBMC) proviral DNA, serum p24 antigen levels, and mononuclear cell subsets were measured at each time point. Mean plasma HIV RNA, PBMC HIV DNA, and p24 antigen [both regular and immune complex dissociated (ICD)] levels did not change significantly between mornings and afternoons or on successive days or weeks.

Quantitation of human immunodeficiency virus by culture and polymerase chain reaction in response to didanosine after long-term therapy with zidovudine.

Measurements of human immunodeficiency virus by quantitative RNA and DNA polymerase chain reaction (PCR), cell and plasma infectivity dilution cultures, and immune complex-disassociated p24 antigen-capture ELISA were made repeatedly in 10 subjects receiving long-term zidovudine treatment before and after therapy was changed to didanosine. Comparison of baseline assays showed that quantitative cell cultures, plasma RNA, and proviral DNA were measurable in all subjects and that cell culture results were significantly correlated with measures of nucleic acids. Plasma viremia (as indicated by culture) and p24 antigen were detected in three measurements in 3 of 8 and 6 of 10 subjects, respectively.

Continuous presence of CD4-PE40 is required for antiviral activity against single-passage HIV isolates and infected peripheral blood mononuclear cells.

CD4-PE40, a recombinant protein consisting of a portion of human CD4 linked to Pseudomonas aeruginosa exotoxin, was studied in vitro to assess its ability to inhibit the replication of primary isolates of HIV. CD4-PE40 was added to cultures of phytohemagglutin (PHA)-stimulated normal peripheral blood mononuclear cells (PBMCs) infected either with the laboratory strain HIVIIIb or single-passage virus stocks derived from patient PBMCs. Results showed that the replication of HIVIIIb was inhibited by a single pulse of CD4-PE40 and, more significantly, by continuous exposure to the drug.

Biological variation and quality control of plasma human immunodeficiency virus type 1 RNA quantitation by reverse transcriptase polymerase chain reaction.

Quantitation of human immunodeficiency virus type 1 (HIV-1) RNA in the plasma of seropositive individuals was performed by using an external control assay with techniques to standardize and control each measurement. Rigorous study of the variability of the assay showed that the median intraassay reproducibility was log10 0.15 RNA copies per ml of plasma, while the median interassay reproducibility on replicate plasma samples was log10 0.

Detection of human immunodeficiency virus type 1 in semen: effects of disease stage and nucleoside therapy.

The effects of clinical stage of infection and antiviral therapy on the detection of human immunodeficiency virus type 1 (HIV-1) nucleic acids in semen were investigated by the polymerase chain reaction. HIV-1 was detected in 45 (87%) of 52 semen specimens from 29 (81%) of 36 men. Seventeen (77%) of 22 stage II or III subjects and 12 (86%) of 14 stage IV subjects had positive specimens.

Measurement of HIV virus load and genotypic resistance by gene amplification in asymptomatic subjects treated with combination therapy.

Quantification of viral load in HIV disease has become increasingly important as a marker of antiviral efficacy. We applied gene amplification techniques in vivo to asses antiretroviral activity of combination therapy. Five HIV-infected subjects, four of whom were drug naive, were administered combination therapy with zidovudine (ZDV) and didanosine (ddI).

A mutation in human immunodeficiency virus reverse transcriptase and decline in CD4 lymphocyte numbers in long-term zidovudine recipients.

A nested polymerase chain reaction assay was used to define the sequence of a specific codon, amino acid 215, of the human immunodeficiency virus (HIV) pol gene in DNA from peripheral blood mononuclear cells (PBMC) and viral RNA from serum from 38 patients treated with zidovudine for > or = 2 years. After treatment for a mean of 34 months, 17 patients with sequences with a codon 215 mutation had a mean 50% decrease in CD4 cells, compared with 21 patients with sequences wild-type at codon 215, who had a mean 11% increase in CD4 cells (P < .0001).

Quantitative RNA and DNA gene amplification can rapidly monitor HIV infection and antiviral activity in cell cultures.

We have developed a quantitative gene amplification procedure to assess the replication of human immunodeficiency virus (HIV) in cell cultures and evaluate the effect of drugs on viral replication. Increases in HIV gag RNA and DNA in phytohemagglutinin-stimulated normal peri-pheral blood mononuclear cells (PBMC) infected with HIV at very low multiplicity of infection paralleled the production of HIV p24 antigen in culture supernatants. Quantitative gene amplification was able to monitor the accumulation of viral nucleic acids in control cultures and demonstrate the effect of various concentrations of azidothymidine (AZT) on the replication of both AZT-sensitive and -resistant strains of HIV.

Rapid method for epidemiological evaluation of gram-positive cocci by field inversion gel electrophoresis.

We report a rapid method for the isolation of intact chromosomal DNA from gram-positive cocci that is suitable for in situ restriction endonuclease digestion in agarose blocks. When combined with a rapid field inversion gel electrophoresis protocol, this approach allows the preparation and electrophoretic analysis of chromosomal restriction fragments produced by rare-cutting enzymes in a total time period of 2 days from start to finish. The utility of the method is demonstrated in the epidemiological evaluation of Staphylococcus epidermidis clusters from two hospitals as well as of additional representative staphylococci and enterococci.

Conservation of receptor expression and phagocytic activity of murine macrophages exposed to various ultrasonic regimens in vitro.

Murine peritoneal macrophages insonated in vitro at 37 degrees C were assayed for impairment of adhesion to and spreading on glass coverslips, expressions of Fc gamma and C3b receptors, and phagocytosis. Insonation conditions were typical for exposures by B-mode imaging equipment and approximated the most severe exposures anticipated in use of pulsed Doppler equipment. In no case were the assay results for insonated samples significantly different from those for the sham-exposed controls.

Detection and quantification of gene amplification products by a nonisotopic automated system.

We describe in this report the ability to determine human immunodeficiency virus proviral copy number by an automated nonisotopic method. Our system utilizes a FACStarPLUS cell sorter, the GeneAmp PCR System 9600 and a Biomek 1000 robotic workstation. Linking these three machines allows cell populations to be sorted and the DNA amplified and quantitated with minimal technical effort.