Permanent pacing in patients with univentricular heart.

Patients with one of several varieties of malformation designated as "univentricular hearts" may be especially challenging when permanent pacing is required. Our objective was to review our experience in this subset of patients that had undergone permanent pacing and thus determine the optimal approach. A retrospective chart review was done of 32 patients with some variety of "univentricular" malformation who had required permanent pacing at our institution. Although technically challenging, permanent pacing in this group of patients can be successful through several approaches. The various approaches, as well as consideration of the differences that exist between patients undergoing septation and those undergoing a Fontan procedure are discussed. Although long-term permanent pacing is possible in this group of patients, before pacing begins, a thorough understanding of the anatomy and prior surgical procedures is necessary. Use of a combined atrial transvenous and ventricular epicardial pacing system may work well for some patients. With the development of newer and more reliable coronary sinus leads, dual chamber transvenous pacing with ventricular stimulation via the coronary sinus could become the approach of choice in some patients with "univentricular hearts."

Lack of correlation between human herpesvirus-6 infection and the course of human immunodeficiency virus infection.

Human herpesvirus-6 (HHV-6) and human immunodeficiency virus (HIV) are both tropic for CD4+ lymphocytes. To determine whether HHV-6 infection affects the susceptibility to or the course of HIV infection, HHV-6 titers were measured by an anticomplement immunofluorescence assay in serum of three groups of homosexual or bisexual men: (1) those with AIDS (n = 78), (2) those with HIV-associated lymphadenopathy (LAS; n = 81), and (3) those who were HIV-seronegative (n = 55). Early and late serum samples were available for 45 men with LAS (median interval 49 months). Men with early LAS did not differ from HIV-seronegative men in either the percentage that were HHV-6-seropositive or in the distribution of titers. There was a significantly lower percentage of seropositives in AIDS patients than in the other two groups (P less than .01). LAS patients who progressed to AIDS did not differ in percentage seropositivity or distribution of titers from nonprogressors. HHV-6 titers tended to decrease over time. HHV-6 titers late in LAS were similar to those in AIDS patients. These findings suggest that it is unlikely that previous exposure to HHV-6 either predisposes to or affects the course of HIV infection.

Comparative study with in situ hybridization and immunocytochemistry in detection of HIV-1 in formalin-fixed paraffin-embedded cell cultures.

The sensitivities of three immunohistological techniques were compared in this study for detecting human immunodeficiency virus (HIV-1) in infected cultured human lymphocytes that had been formalin-fixed and paraffin-embedded. The techniques included in situ hybridization (ISH) with HIV-1 cDNA; immunocytochemistry with HIV-1 p24 monoclonal antibody (ICC-m); and immunocytochemistry with HIV-1 polyclonal antibody from a patient with acquired immunodeficiency syndrome (AIDS) (ICC-p). Procedures were optimized for enzyme digestion and for antibody reaction conditions. HIV-1--infected cells and noninfected control cells were tested. Noninfected controls were uniformally negative by all three methods. Infected cells had the highest positivity rate by the ISH method (p less than or equal to 0.0001), and the ICC-p method was more positive than the ICC-m (p less than or equal to 0.0001). Both the ICC-p and the ICC-m techniques were more positive with the cocultivated cell cultures than the ISH, which was more sensitive with the infected continuous cell line (P less than or equal to 0.0001). The ICC-p method had a lower standard deviation on positive results than either the ICC-m or ISH method. The variability observed with these test procedures, reagents, and specimens suggests that these are important technological parameters in detecting p24, with implications for detecting other HIV-1 markers in infected tissues.

Demonstration of human immunodeficiency virus by colorimetric in situ hybridization: a rapid technique for formalin-fixed paraffin-embedded material.

A colorimetric method of in situ hybridization has been developed for the rapid detection of human immunodeficiency virus (HIV) in formalin-fixed paraffin-embedded material. Following optimization of digestion conditions, biotin-labeled DNA probes are detected with an alkaline phosphatase conjugate. The method is verified using fixed paraffin-embedded cell blocks of HIV-infected and uninfected lymphocyte cell cultures. Hybridization specifically detects both viral RNA and proviral DNA. Formalin fixation for intervals up to 21 d did not significantly hamper the signal under the appropriate digestion conditions; however, Trump's fixation for even 12 h greatly reduced the intensity of the hybridization. This technique for in situ hybridization is amenable to automation, provides results within 6 h, and results in good morphologic preservation. A key feature of the technique is the use of human placental DNA as an endogenous positive control to optimize the empirically determined conditions for protein digestion.

DNA amplification for direct detection of HIV-1 in DNA of peripheral blood mononuclear cells.

By means of a selective DNA amplification technique called polymerase chain reaction, proviral sequences of the human immunodeficiency virus (HIV-1) were identified directly in DNA isolated from peripheral blood mononuclear cells (PBMCs) of persons seropositive but not in DNA isolated from PBMCs of persons seronegative for the virus. Primer pairs from multiple regions of the HIV-1 genome were used to achieve maximum sensitivity of provirus detection. HIV-1 sequences were detected in 100% of DNA specimens from seropositive, homosexual men from whom the virus was isolated by coculture, but in none of the DNA specimens from a control group of seronegative, virus culture-negative persons. However, HIV-1 sequences were detected in 64% of DNA specimens from seropositive, virus culture-negative homosexual men. This method of DNA amplification made it possible to obtain results within 3 days, whereas virus isolation takes up to 3 to 4 weeks. The method may therefore be used to complement or replace virus isolation as a routine means of determining HIV-1 infection.

Comparison of antigen assay and reverse transcriptase assay for detecting human immunodeficiency virus in culture.

We compared an antigen capture assay (Abbott Laboratories, North Chicago, Ill.) with a reverse transcriptase assay to identify and quantify human immunodeficiency virus (HIV) in culture. In direct comparisons of serial dilutions of lymphadenopathy-associated virus type 1, the antigen assay was 100-fold more sensitive than the reverse transcriptase assay in detecting the virus. The antigen assay reacted strongly with 60 different HIV isolates but did not cross-react with human T-cell lymphotropic virus type I, human T-cell lymphotropic virus type II, cytomegalovirus, varicella-zoster virus, herpes simplex virus type 1, Epstein-Barr virus, adenovirus type 5, or poliovirus type 1 or with extracts from four different control human cell lines and eight different phytohemagglutinin-stimulated normal human lymphocytes. Peripheral blood lymphocyte samples from 50 individuals were evaluated by both the antigen assay and the reverse transcriptase assay. The cells from the 34 seropositive individuals were all positive by the antigen assay (range, 3 to 9 days; average time, 5.9 days) and the reverse transcriptase assay (range, 7 to 16 days; average time, 9.6 days). Cells from the 16 seronegative individuals were negative by both assays. These results indicate that the antigen assay is an important addition to the monitoring of HIV production in the lymphocytes of infected patients.

Micromethod for assaying reverse transcriptase of human T-cell lymphotropic virus type III/lymphadenopathy-associated virus.

A micromethod for assaying the reverse transcriptase enzyme of human T-cell lymphotropic virus type III/lymphadenopathy-associated virus in cocultures of clinical specimens for viral isolation was developed and compared with the macromethod in use. Ultracentrifuged, pelleted, and solubilized viral culture supernatants were transferred into either tubes (macromethod) or microtiter plates (micromethod) and incubated with tritiated enzyme substrate. Trichloroacetic acid-precipitated DNA was collected on individual filter papers with a Millipore filtration manifold (macromethod) or on filter sheets using a semiautomated cell harvester (micromethod). Filters were then placed in scintillation fluid and counted on a beta scintillation counter. Results of the micromethod significantly correlated to those of the macromethod, with a linear relationship between the two. The cutoffs for positivity based on the mean + 2 standard deviations for a set of known negative specimens (n = 19) was 4,973 cpm for the micromethod compared with 5,336 for the macromethod. The intrarun and interrun variations were comparable for both methods. There was a 67% increase in the maximal daily number of specimens which could be run (100 versus 60) as well as a reduction in reagent use. In summary, the micromethod utilizing a semiautomated cell harvester is comparable to the existing macromethod in accuracy and is an improvement due to savings in time and reagents.

Virologic studies of HTLV-III/LAV in pregnancy: case report of a woman with AIDS.

The number of cases of acquired immunodeficiency syndrome (AIDS) in women is increasing. As of December 30, 1985, 1075 cases in women had been reported to the Centers for Disease Control; 81% of these cases occurred in women of childbearing age (15 to 45 years). The human T-lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV) can be transmitted from mothers to their infants. Described is a woman with transfusion-acquired AIDS who was six weeks' pregnant at the time Pneumocystis carinii pneumonia was diagnosed. Despite the fact that HTLV III/LAV was isolated from her peripheral lymphocytes throughout pregnancy, transmission of the virus to her infant or husband does not appear to have occurred.

The safety of the hepatitis B vaccine. Inactivation of the AIDS virus during routine vaccine manufacture.

In the United States, one hepatitis B vaccine (Heptavax-B) has been licensed for the prevention of hepatitis B virus infections. Even though this vaccine has been shown to be highly effective and well tolerated in controlled trials and has been recommended for use in those at risk for acquiring infection by hepatitis B virus, many individuals have been reluctant to be immunized for fear of contracting acquired immunodeficiency syndrome (AIDS). In this study, we demonstrate that each of the three inactivation steps used in the manufacture of Heptavax-B independently will inactivate the infectivity of high-titered preparations of the AIDS virus; recipients of the hepatitis B vaccine do not develop antibodies to the AIDS virus; the hepatitis B vaccine does not contain detectable levels of nucleic acids related to the AIDS virus. These observations clearly demonstrate that vaccination with the currently available hepatitis B vaccine poses no demonstrable risk for acquiring AIDS.

Transfusion-associated acquired immunodeficiency syndrome in the United States.

By Aug 15, 1985, one hundred ninety-four cases of possible transfusion-associated acquired immunodeficiency syndrome (AIDS) had been reported to the Centers for Disease Control. Cases received their transfusions in 30 states. Infants account for 10% of the cases, suggesting an increased susceptibility to developing AIDS. Investigations one to six years after the transfusions have identified high-risk donors to 47 cases. Of 47 high-risk donors tested, 40 had a reactive serology for human T-cell lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV) antibody, including five with no risk for AIDS by history. The HTLV-III/LAV was isolated from 23 of 26 seroreactive high-risk donors, most of whom remained asymptomatic. Blood components that transmitted HTLV-III/LAV included red cells, platelets, plasma, and whole blood. The time from transfusion to diagnosis of AIDS ranged from four to 84 months. The risk of developing AIDS after a blood transfusion has been low and will be lowered further by using both self-deferral and antibody screening.

LAV/HTLV III presence in peripheral blood lymphocytes of seropositive young hemophiliacs.

Recent studies indicate a high prevalence of seropositivity to the lymphadenopathy-associated virus/human T-lymphotropic virus (type III) among individuals with hemophilia exposed to clotting factor concentrates prepared from large donor pools. The peripheral blood lymphocytes of 19 young seropositive patients with inherited bleeding disorders were examined for the presence of this virus by coculture with phytohemagglutinin-stimulated lymphocytes. Viral isolates were obtained from six of 19 patients. While none of these patients have developed the acquired immunodeficiency syndrome (AIDS) or AIDS-related complex, five of them had lymphadenopathy in two noncontiguous areas, and two showed clinically symptomatic enlarged tonsils and adenoids. Of the 13 patients in whom virus was not demonstrated, five were judged clinically normal and five had mild lymphadenopathy in one anatomical area. These results suggest that as many as 33% of hemophiliacs (six of 19 patients studied), who have circulating antibodies to mature viral proteins, have viral-infected peripheral blood lymphocytes capable of infecting other lymphocytes in vitro.

Persistent infection with human T-lymphotropic virus type III/lymphadenopathy-associated virus in apparently healthy homosexual men.

PIP: A group of 14 apparently health homosexual men with serologic evidence of human T-lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV) infection were studied to determine the duration of their seropositivity, their immunologic status, and the frequency of isolation of HTLV-III/LAV from their peripheral blood. The men were selected from a larger sample of patients who attended a clinic for treatment of sexually transmitted diseases in San Francisco because they did not have acquired immunodeficiency syndrome (AIDS), signs or symptoms suggestive of the prodrome of AIDS, or laboratory evidence of anemia or leukopenia. 4 or more serum samples were available from previous clinic visits. The men ranged in age from 26-41 years, and had a median number of sexual partners in the last year of 23. The estimated duration of seropositivity ranged from 4-69 months (median, 33 months). 11 of the 14 had T-helper: T-suppressor cell ratios below 1 (the lower limit of normal), and low ratios were significantly correlated with duration of seropositivity. HTLV-III/LAV was isolated in peripheral blood samples from 8 of 12 men tested. Culture-positive and culture-negative men did not differ significantly in terms of age, presence of a palpable lymph node, T helper:T-suppressor cell ratio, or duration of seropositivity. These findings suggest that some seropositive men may remain asymptomatic for at least 5 years. However, the isolation of HTLV-III/LAV from the peripheral blood of most of these men indicates persistent infection may be common among asymptomatic seropositive men at risk for AIDS. It should be assumed that these men have the potential to transmit HTLV-III/LAV infection.^ieng

Lymphadenopathy associated virus infection of a blood donor--recipient pair with acquired immunodeficiency syndrome.

A retrovirus isolated from three patients with the acquired immunodeficiency syndrome (AIDS) in the United States was morphologically and antigenically identical to lymphadenopathy associated virus isolated in France. Two of these isolates were from a blood donor-recipient pair, each of whom developed AIDS. Lymphadenopathy associated virus was isolated from the blood donor's lymphocytes 12 months after his onset of AIDS symptoms and from the blood recipient's lymphocytes 1 month after her onset of AIDS symptoms. Two isolates from the blood donor-recipient pair and an isolate from an epidemiologically unrelated homosexual man were examined by competitive radioimmunoassay to determine their antigenic relatedness to each other and to other human retroviruses. The major core proteins (p25) of the isolates were antigenically identical and all three isolates were identical to prototype lymphadenopathy associated virus isolated in France.

Experimental allergic neuritis-like disease in rabbits after injection with influenza vaccines mixed with gangliosides and adjuvants.

An experimental allergic neuritis-like disease was induced in rabbits 3 to 8 weeks after injection with large doses of influenza vaccines mixed with gangliosides, cholesterol, and Freund complete adjuvant. The inclusion of gangliosides was essential to induce the experimental allergic neuritis-like disease. In trials with six different lots of vaccine, both swine influenza and non-swine influenza vaccines produced by four different manufacturers induced experimental allergic neuritis-like disease in 26 of 43 inoculated rabbits.

Ultrasonic potentiation of the sporicidal activity of glutaraldehyde.

Laboratory test data showed a 4.8-fold increase in the sporicidal activity of glutaraldehyde with the incorporation of ultrasound. Projected times required for 100 percent killed of a 20,000 hydrated spore inoculant were reduced from 211 minutes to 44 minutes. Clinical exposure time intervals necessitated a 31/2-hour glutaraldehyde immersion versus a 30-minute cavitated glutaraldehyde chemosterilization to ensure a 100 percent kill. The feasibility of reducing the ADA-required 10-hour soak in glutaraldehyde to ensure sterility with the incorporation of ultrasonic baths is supported by these data. Tests performed also showed that the airborne contamination from an open tank method is minimal. No spores were retrieved from vapor collected by passive vacuum during cavitation of inoculated glutaraldehyde.