Isolated renal mucormycosis in two AIDS patients

Two cases of mucormycosis in patients with exclusively renal involvement and advanced HIV infection are reported. In both cases the clinical course was relatively benign; in one case a tendency towards regression with no specific treatment was observed, and in the other case the infection resolved after nephrectomy and antifungal therapy. Renal mucormycosis should be considered in the differential diagnosis of diffuse renal enlargement in HIV-infected patients.

Provirus load changes in untreated and zidovudine-treated human immunodeficiency virus type 1-infected patients

Human immunodeficiency virus type 1 (HIV-1) provirus burden was quantified during follow-up of untreated patients and mathematically analyzed by a parameter called intrinsic rate of increase (r). There was an increase in provirus burden in patients at early stages of the infection, and the increase occurred at a similar rate in later stages of the disease. Antiviral response to zidovudine was evaluated using r. Nearly 50% of patients responded with strong decreases of r, and the rest behaved as nonresponders. Parameter r is valuable in disease prognosis, as the mean r was higher in disease progressors than in nonprogressors, and this difference was significant and more pronounced in treated patients. The zidovudine resistance mutation at codon 215 of reverse transcriptase was associated with a worse response to therapy. Absence of antiviral response and resistance mutations were more frequent in patients with lower CD4+ cell counts and higher provirus loads. These findings support a more beneficial effect of early than late therapy.

Effects of systemic clonidine on auditory event-related potentials in squirrel monkeys

Event-related potential (ERP), electroencephalographic (EEG), and behavioral data were collected from squirrel monkeys (Saimiri sciureus) in a 90-10 auditory oddball paradigm. Background or target tones were presented once every 2 s, and responses to the targets were rewarded. ERPs were recorded from epidural electrodes following systemic administration of clonidine (0.1 mg/kg) or a saline placebo. EEG power spectral and behavioral performance were assessed simultaneously as indices of behavioral state. Clonidine significantly decreased the area and increased the latency of a P300-like potential. The amplitude and areas of the earlier P1, N1, and P2 components and a later slow wave-like potential were not reduced, nor were ther latencies altered. Clonidine produced increased EEG power in the alpha range (7.5-12 Hz) and decreased power in the upper beta range (20-40 Hz) but did not affect performance in the oddball task. Because two major effects of clonidine are to substantially reduce activity in the noradrenergic nucleus locus coeruleus (LC) and to reduce norepinephrine (NE) release from axons, the present results support the hypothesis that the LC and its efferent projection system are important in modulating the activity of P300-like potentials.

Locus coeruleus neuronal activity in awake monkeys: relationship to auditory P300-like potentials and spontaneous EEG

These experiments were designed to test the hypothesis that novel auditory stimuli lead to phasic and/or tonic increases in locus coeruleus (LC) cell firing, which may be a necessary condition for the occurrence of P300 potentials. Event-related potentials (ERPs) and LC unit activity were simultaneously recorded from three awake macaque monkeys exposed to an auditory "oddball" paradigm. Oddball stimuli resulted in probability-sensitive potentials resembling the human P3a component. Twenty-five percent (3/12) of LC units showed small phasic enhancements of LC firing after infrequent but not frequent tones. A comparison between histograms elicited by the two types of stimuli revealed significant effects of stimulus sequence. This pattern suggested a slight activation by rare tones, followed by a brief inhibition of firing in the subsequent trial. These data suggest that changes in LC activity during oddball paradigms are subtle, heterogeneous, and influenced by the subject's level of arousal and vigilance.

Hepatitis C virus infection among sexually promiscuous groups and the heterosexual partners of hepatitis C virus infected index cases

To define the role of sexual transmission in the spread of hepatitis C virus (HCV) infection, a seroprevalence study of antibodies against HCV was performed in populations at high risk for sexually transmitted diseases. Subjects included 310 female prostitutes, 88 clients of prostitutes, 168 homosexual men and 147 stable heterosexual partners of index cases reactive for anti-HCV (98 of whom were partners of drug addicts coinfected with HCV and human immunodeficiency virus [HIV]). All subjects denied prior transfusion or intravenous drug use. Controls were 400 voluntary blood donors selected randomly from first-time donors. The prevalence of anti-HCV by enzyme immunoassay, confirmed by a second-generation recombinant immunoblot assay, was 6.4% in prostitutes, 6.8% in clients of prostitutes, 4.2% in homosexual men, 7.4% in heterosexual partners of index cases and 1.2% in random donors. However, the anti-HCV prevalence in stable heterosexual partners of HCV-positive/HIV-positive index cases was 2.2 times higher than in stable heterosexual partners of index cases reactive for anti-HCV only (9.2% vs. 4.1%), and sexual partners of index cases coinfected with HCV and HIV were almost three times more likely to be infected with HIV than with HCV (25.5% vs. 9.2%). These data suggest that HCV infection may be sexually transmitted but with low efficiency and that this efficiency could be increased in the presence of coexistent HIV infection in the index case.

Failure to detect silent HIV infection by polymerase chain reaction in subjects at risk for heterosexually transmitted HIV type 1 infection

The prevalence of silent HIV-1 infections in subjects at risk of acquiring HIV infection by heterosexual transmission was assessed using a nested polymerase chain reaction (PCR) assay. The two groups of risk subjects consisted of 92 female prostitutes and 43 heterosexual partners of infected individuals. Appropriate positive and negative control persons were included in the study. Serum samples were also tested for antibody to HIV-1 by an enzyme immunoassay (EIA) and positive results confirmed by Western blot. PCR results in the two risk groups and the positive and negative controls were in full agreement with serological results. It is concluded that silent infection with HIV-1 is infrequent in persons at risk for heterosexual transmission.

Hepatitis B virus occult infection in subjects with persistent isolated anti-HBc reactivity

The aim of this study was to investigate the presence of hepatitis B virus occult infection in asymptomatic subjects with persistent anti-HBc reactivity but no other hepatitis B virus serological markers, including HBsAg, anti-HBs, IgM anti-HBc and HBV-DNA. For this purpose we used both polymerase chain reaction assays in sera and immunohistochemistry for HBsAg and HBcAg in liver biopsy specimens. Twenty-four cases were studied: 15 were drug abusers or homosexuals (eight with normal alanine aminotransferase levels) and nine were heterosexuals with raised alanine aminotransferase levels (> 45 U/l) but with no history of blood transfusion or ethanol intake (< 80 g daily). In all but five cases, liver biopsy was performed in subjects with persistent elevated alanine aminotransferase levels. In 10 out of 24 cases (41.66%) hepatitis B virus infection was demonstrated by polymerase chain reaction or immunohistochemistry, and when results from both procedures were available (n = 11) hepatitis B virus infection was detected in 63.63% of the subjects. The only clinical feature associated with HBV infection was the presence of persistent elevated alanine aminotransferase levels (p < 0.05). In conclusion, persistent isolated anti-HBc reactivity may be a relatively common serologic pattern for hepatitis B virus occult infection, at least in patients with chronic liver disease.

Event-related potentials in macaque monkey during passive and attentional processing of faces in a priming paradigm

Epidural event-related potentials (ERPs) were recorded in monkeys using a priming (S1-S2) paradigm. One juvenile and 2 young adult macaque monkeys (Macaca fascicularis) viewed tachistoscopically presented pairs of faces in four possible combinations: human-human, monkey-monkey, monkey-human, human-monkey. Faces were presented upright to untrained subjects. Subsequently, one adult monkey was trained to associate the occurrence of a monkey-monkey pair of faces with juice reward. In a separate control experiment, the same stimuli were presented upside down. In both the upright and inverted conditions, adult monkey ERPs exhibited a P1-N1-P2 complex of peaks in the 400 ms following stimulus presentation. However, only upright faces elicited a prominent, widely distributed negativity (N4) in the 400-800 ms interval and a long-duration negativity (LDN) in the last 400 ms of the 1,400-ms epoch. N4 was earlier in latency, larger in amplitude, and larger over left hemisphere in response to monkey faces compared to human faces. It was also sensitive to the preceding or priming stimulus, exhibiting larger amplitudes when S1 matched S2 than when it did not. Trained monkey waveforms differed from untrained monkey responses in terms of the appearance of an N2-P3 complex. P3 was bilaterally symmetrical, larger in magnitude, and delayed in latency in response to monkey faces. The differences in components in the two conditions suggest that monkey ERPs can distinguish between passive and attentional processing of faces. N4 appears to reflect the recognition of conspecifics, is sensitive to priming, and occurs primarily over left hemisphere. Rewarded presentation of faces results in P3-like components that may reflect the novelty, meaningfulness, or active nature of the response. The differences in distribution between P3 and N4 suggest that they do not share the same neural sources.

[Prevalence of antibodies against hepatitis C virus in a sample of homosexual males]

BACKGROUND

The finding of an important proportion of cases of hepatitis C without previous contact with blood or hemoderivates has led to suspect that there may be other routes of transmission among which sexual transmission may be found.

METHODS

The presence of antibodies against the hepatitis C virus (anti-HCV) and the association of this infection with certain epidemiologic parameters and sexual practice was determined in 184 homosexual males with no other risk factors for virasis of intravenous transmission. Moreover, the prevalence of anti-HCV was evaluated in 210 voluntary blood donors. Every homosexual was surveyed on sexual practice and the first serum sample available of each of these patients was analyzed for anti-HVC and anti-HIV-1.

RESULTS

Twenty-two homosexual (12%) were anti-HCV positive while only one (0.5%) of the control was positive for this marker (p < 0.0001). Thirty-six cases (19%) were anti-HIV positive (none of the controls). No statistical association was found between both serologic markers or between the presence of anti-HCV and the epidemiologic parameters evaluated.

CONCLUSIONS

Homosexuals constitute a risk group for hepatitis C virus infection although the sexual route is probably not effective for transmission of this entity.

Monkey P3 in an "oddball" paradigm: pharmacological support for multiple neural sources

Two experiments examined the effects of the alpha-2 antagonist L657,743 on monkey electroencephalographic (EEG) and event-related potential (ERP) activity following auditory and visual stimuli. In the first experiment, EEG was recorded before and after the administration of a saline placebo or L657,743 (0.01, 0.05 mg/kg IM). No drug effects occurred on EEG spectral frequencies. In the second experiment, ERPs were recorded during an 80-10-10 passive oddball paradigm. The paradigm consisted of a repetitive tone as background, a different-pitch tone as the auditory oddball, and a yellow rectangle as an infrequent visual stimulus. Waveforms were collected before and after the administration of placebo or drug (0.01, 0.03, 0.05 mg/kg IM). Both auditory oddball and visual stimuli elicited large P3-like potentials with different distributions, suggesting different sources. However, their magnitudes were similarly reduced by drug administration. These effects were significant at parietal but unchanged at other sites. The data support the hypothesis that norepinephrine is a modulatory neurotransmitter common to auditory and visual P3s in parietal areas. On the other hand, midline and temporal P3s are unaffected by manipulations of noradrenergic activity, supporting the existence of two independent P3 sources.

Visceral leishmaniasis in HIV-1-infected individuals: a common opportunistic infection in Spain?

OBJECTIVE

To investigate the epidemiological, clinical and biological features of visceral leishmaniasis (VL) in patients with HIV-1 infection.

DESIGN

Retrospective study.

SETTING

Three university hospitals in southern Spain.

PATIENTS

Forty-seven adult patients with VL and HIV-1 infection diagnosed between January 1986 and November 1991.

RESULTS

Forty-five out of the 47 (96%) cases were diagnosed in the last 2 years. Fever (87%), hepatomegaly (74%), splenomegaly (72%) and pancytopenia (77%) were the most common presenting features. Most patients (79%) were strongly immunocompromised when VL was diagnosed, and were in stage IV of the Centers for Disease Control classification; 87% had a CD4 lymphocyte count < 200 x 10(6)/l. However, VL was the first severe infection diagnosed in 10 cases. Significant titres (> 1:40) of antileishmanial antibodies were detected by indirect immunofluorescence in five out of 16 (31%) cases only. Clinical response to the therapy was difficult to assess. Microbiological response was achieved in only 38% of the patients evaluated.

CONCLUSIONS

Leishmaniasis is a relatively common infection in HIV-1-infected individuals in southern Spain. Its clinical picture is quite uniform and it can be the first opportunistic infection in individuals with HIV-1. In endemic areas, a high index of clinical suspicion should be maintained in order to avoid underdiagnosis of leishmaniasis.

HIV-1 infection among non-intravenous drug user female prostitutes in Spain. No evidence of evolution to pattern II

OBJECTIVES

To assess the prevalence of HIV-1 infection among non-intravenous drug user (IVDU) female prostitutes in Spain and to determine risk factors for HIV-1 infection in this population.

DESIGN

Cross-sectional seroepidemiological study of 519 non-IVDU prostitutes.

SETTING

Four university hospitals.

METHODS

All participants completed a questionnaire and provided a serum sample. Serum samples were tested for antibodies against HIV-1, hepatitis C virus (HCV) and Treponema pallidum.

RESULTS

Twelve out of the 519 (2.31%) participants were HIV-1-seropositive. HIV-1 infection was associated with the presence of both HCV and T. pallidum antibodies, multiple sex partners, longer history of prostitution, history of genital ulcers and anal intercourse. Condom use was associated with HIV-1 seronegativity.

CONCLUSIONS

The prevalence of HIV-1 infection in non-IVDU prostitutes in Spain remains relatively low. Risk increases with a higher rate of sexual exposure and practices such as anal intercourse and unprotected coitus.

[Multicenter study of the prevalence of type 2 human immunodeficiency virus infection in Spain (1990)]

BACKGROUND

HIV-2 is a new retrovirus which may produce AIDS and has been mainly described in individuals from West Africa. More than 400 cases have been reported in France and Portugal while in Spain very few cases of HIV-2 infection have been reported with few studies having been made concerning the prevalence of the disease. This multicentric study analyzes the prevalence of HIV-2 infection in subjects of different risk groups in Spain and evaluates the diagnostic efficacy of different methodologies.

METHODS

The presence of HIV-2 antibodies was analyzed in 902 serum samples of high risk individuals collected in 1990 from: 386 drug addicts, 246 not drug addict prostitutes, 184 West Africans and 86 homo/bisexual individuals. These samples were from Barcelona, Sevilla, and Malaga. The detection of antibodies was carried out by enzymatic immunoanalysis (EIA), Western blot (WB) and an enzymoimmuno-dot (EID) designed with synthetic peptides.

RESULTS

Positive serology only for HIV-2 was detected in 7 samples from African immigrants. Two drug addicts presented double reactivity HIV-1/HIV-2 in all the tests suggesting double infection. No prostitutes or homo/bisexual males were identified with positive serology for HIV-2. Cross-reactivity between HIV-1 and HIV-2 was more frequently detected in WB than in EID. Greater discordance was found in the results obtained by EIA, WB, and EID in the West Africans than in the analysis of the samples of native subjects.

CONCLUSIONS

This study demonstrates that, for the time being, HIV-2 infection in Spain is rare although from among immigrants from endemic areas subjects with behavior to risk of transmission to the autochthonous population have been identified. The use of techniques designed with synthetic peptides may be of use to discriminate HIV-1 and HIV-2 infection in positive samples by enzymatic immunoanalysis (EIA) and Western blot which use a viral lysate as antigenic material.

Visual P3-like potentials in squirrel monkey: effects of a noradrenergic agonist

Event-related potentials (ERPs) were recorded from squirrel monkeys (Saimiri sciureus) in a 90-10 visual "oddball" paradigm. A small, blue rectangle was presented every 2 s on 90% of the trials (background), whereas a yellow rectangle occurred on 10% on the trials (oddball). Electrical activity time-locked to these stimulus events was recorded from epidural electrodes before and following systemic administration of the alpha-2 noradrenergic agonist clonidine (0.1 mg/kg intramuscularly, IM). Baseline data in response to oddball stimuli showed a large, P3-like potential exhibiting a fronto-central maximum along midline electrodes and a parietal maximum along lateral electrodes. A frontally dominant, long-latency, negative slow wave (SN) consistently followed this P3-like potential. Amplitudes for P3 were larger following 10% than 50% probable oddball events. These results suggest that monkeys exhibit large, probability-sensitive P3-like potentials similar to the visual potentials reported in humans. Administration of clonidine had no effect on the amplitude, area, or latency of the monkey P3 component. This contrasts with our previous findings that the same dose of clonidine significantly decreases auditory P3s in these monkeys. Such differences may reflect distinct functional roles for norepinephrine in the processing of low-probability acoustic versus visual signals and argues against the hypothesis that norepinephrine is a common neurotransmitter substrate for auditory and visual P3-like potentials.

Absence of HTLV-I and HTLV-II infection in prostitutes in the area of Seville, Spain

Infection with human retroviruses other than HIV in Spain has only been reported in isolated cases in African immigrants and intravenous drug abusers infected with HTLV-I. The status of the prostitute population is unknown. The sera of 88 prostitutes in Seville were therefore tested for HIV, HTLV-I and HTLV-II, and relevant epidemiological data were collected on the health status, sexual practices etc. In the prostitute population studied 2.5% of the non-intravenous drug abusers and 20% of the intravenous drug abusers were positive for HIV. However, infection with HTLV-I/II could not be demonstrated in any of them.

Intensity-amplitude relationships in monkey event-related potentials: parallels to human augmenting-reducing responses

In human, the amplitudes of specific event-related potential (ERP) components can increase or decrease in response to increasing stimulus intensity depending on the location of the recording site. Large increases characterize components presumably generated by modality-specific sites, while smaller increases or even decreases are associated with those originating in associational areas. Comparable data from non-human primates, which would permit invasive studies of the neural substrates underlying these intensity-amplitude differences, are limited. To more fully characterize these relationships, auditory ERPs were recorded from chronically implanted epidural electrodes in 5 squirrel monkeys (Saimiri sciureus) in response to tones (500 Hz, 300 msec duration) of varying intensities (50, 60, 70, 80 dB SPL). Squirrel monkey ERPs recorded at Fz exhibited 3 peaks during the 200 msec post-stimulus interval. These peaks included a positivity (P1), followed by a negativity (N1), and then another positivity (P2). At posterior sites, the frontal P1-N1 configuration was recorded as an N1-P1 complex. At these sites, a small negativity (N2) preceded the last positive peak (P2). Changes in polarity were independent of reference site and posterior N1-P1 peaks exhibited latencies similar to those of the frontal P1-N1 components. Amplitudes at Fz, Cz, and Pz increased substantially with increasing stimulus intensity ('augmenting'). In contrast, only small increases or even decreases in amplitude ('reducing') were evident at T3 and T4. On the other hand, peak latencies decreased with higher stimulus intensities at most sites. The site-specific amplitude responses exhibited considerable temporal stability. In one subject, for example, similar 'augmenting' profiles were recorded at Fz in 8 sessions over a 6-month period. The topography of monkey intensity-amplitude response profiles, their temporal stability, and peak latency shifts resemble observations made in humans. The data show that 'augmenting' characterizes monkey vertex potentials, which, like the analogous human potentials, may originate in primary auditory cortex. In contrast, potentials recorded over temporal cortex, which may originate in auditory association cortex, exhibit 'reducing.' Thus, the data support the hypothesis that differences in amplitude with increasing intensity may reflect differences in cortical origin.

Therapeutic donor insemination: a prospective randomized study of scheduling methods

OBJECTIVE

To compare basal body temperature (BBT) graphs and urinary luteinizing hormone (LH) monitoring in scheduling therapeutic donor insemination.

DESIGN

Participants were prospectively randomized to the BBT or LH groups.

SETTING

Participants were private patients of the Reproductive Endocrine Division at Washington University School of Medicine.

PATIENTS

Inclusion criteria were designed to assure an isolated male factor. Seventy-four of 113 patients completed the study; 18 had ongoing treatment at the end of the study.

INTERVENTIONS

Basal body temperature graphs were physician interpreted and appointments prospectively chosen. Luteinizing hormone patients monitored daily urine samples and scheduled an appointment the day after the detected surge.

MAIN OUTCOME MEASURES

Fecundity rates, cumulative pregnancy rates, and cost per pregnancy were all prospectively evaluated.

RESULTS

Life table analysis yielded a 6-month cumulative probability of pregnancy of 36.3% in the LH group and 65.1% in the BBT group (P less than 0.025). The total cost per pregnancy was lower in the BBT group (+6,212 versus +3,997; P less than 0.001).

CONCLUSIONS

This randomized prospective study demonstrates significant therapeutic and economic advantages when therapeutic donor insemination is prospectively scheduled by BBT graphs.

Electrophysiological evidence for the involvement of the locus coeruleus in alerting, orienting, and attending

In this chapter, we describe recent observations from our laboratory which support the thesis that the locus coeruleus (LC), via its massively divergent efferent projections, participates in generating a generalized brain state that can be characterized as "alertness." The first of these observations suggests that LC activation can convert the electroencephalographic (EEG) activity of the forebrain from patterns characteristic of a non-alert state to those characteristic of an alert state. The second observation indicates that LC activation alters sensory responses of individual neocortical neurons in a way that is compatible with the general thesis presented here, suggesting that LC-induced alterations in cortical neuronal activity may be an integral component of a hypothesized participation of the LC in cortically mediated attentional processes. The third observation indicates that LC may modulate forebrain components of orienting responses that are indexed by event-related potentials (ERPs). Thus, the experiments described below involve electrophysiological assessment of forebrain information processing at three different levels of organization: activity of individual neurons in the millisecond range, neuronal ensemble activity persisting for 10-200 msec as indexed by ERPs, and ensemble/regional activity sustained for seconds to minutes as indicated by EEG measures. These observations suggest that alterations induced in forebrain function by manipulations of LC activity are evident at all three of these levels.

[An evaluation of the efficacy of different commercial kits in the serological diagnosis of the early phase of human immunodeficiency virus infection]

The aim of the present study was to identify the most useful serum markers for the early identification of the infection by the human immunodeficiency virus (HIV). To this end, sequential serum samples of 19 individuals who later had seroconversion to anti-HIV were evaluated. The p24 antigen (Ag-HIV) was the earliest marker of the infection, although it could only be detected in five of the 19 individuals: in two as an isolated marker and in the remaining four associated to anti-HIV (first generation Western blot: WB-1, and recombinant enzyme immunoanalysis: EIA-2G). In 12 of the 19 individuals, WB-1G (Pasteur) was the technique which permitted the earliest detection of anti-HIV: in five cases with bands which made the unequivocal diagnosis of the infection, and in seven with indeterminate results (anti-HIV against core or envelope antigens). The second earliest test was the detection of anti-HIV against envelope antigens with a competitive EIA-2G (Abbott). WB-1G (Sorin) detected anti-HIV in a late phase, as it was the case for EIA-1G or EIA-2G for anti-HIV against antigens encoded by the GAG gene. These results indicate that there may be remarkable differences in sensitivity among the different commercial kits. The use of EIA for Ag-HIV together with WB-1G shortens the gap period of HIV infection, even if seroconversion is identified with EIA-2G for global anti-HIV.

Stereospecificity of hydrogen transfer between progesterone and cofactor by human placental estradiol-17 beta dehydrogenase

We have previously shown that human placental estradiol-17 beta dehydrogenase (EC 1.1.1.62; 17 beta-EDH) catalyzes the conversion of estradiol-17 beta to estrone and stereospecifically reduces NAD+ to [4-pro-S]NADH, [( 4-B]NADH). Subsequently, this enzyme was found to reduce the ketone function at C-20 of progesterone, and evidence indicates that both activities reside at the same active site. This study was done to further elucidate spatial arrangements of cofactor and the 21-carbon substrate as they bind at the active site. The cofactor, [4B-3H]NADPH, was generated with homogeneous 17 beta-EDH from term human placenta, utilizing [17 alpha-3H]estradiol-17 beta and NADP+. The resulting [4B-3H]NADPH was then purified by ion exchange chromatography and was separately incubated (24.4 microM) with a large molar excess of progesterone (150 microM) as substrate in the presence of the enzyme. Following incubation, the steroid reactants and products were extracted, separated by high-performance liquid chromatography and quantitated as to mass and tritium content. Oxidized and reduced cofactor were separated by ion-exchange chromatography and similarly quantitated. In all incubations, equimolar amounts of 20 alpha-hydroxy-4-pregnen-3-one (20 alpha-OHP) and NADP+ were obtained. Radioactivity was stoichiometrically transferred from [4B-3H]NADPH to the steroid product [( 3H]20 alpha-OHP). These results further substantiate a single active site for both 17 beta- and 20 alpha-dehydrogenation enzyme activities. In addition, the enzyme is B-side specific, catalyzing the transfer of the 4B-hydrogen from the dihydronicotinamide moiety of the cofactor, for both C-18 and C-21 steroid substrates. Since the 20 alpha-dehydrogenation by other enzyme sources has always been demonstrated to be an A-side specific reaction, this observation represents an important exception to the Alworth-Bentley rules of enzyme stereospecificity.

Hepatitis C virus infection in sexually promiscuous groups

As there is insufficient data available on the spread of hepatitis C virus (HCV) infection by sexual transmission, the prevalence of anti-HCV was determined in several sexually promiscuous groups (78 female prostitutes, 55 clients of prostitutes and 146 homosexual men) who denied intravenous drug abuse. The overall HCV infection rate was much higher in the sexually promiscuous groups (8.97%, 16.36% and 5.48% respectively) than in voluntary blood donors (0.48%), suggesting that HCV infection can be transmitted by sexual intercourse. Consequently, promiscuity may be a risk factor for this infection.

[Classical heatstroke in Spain. Analysis of a series 78 cases]

Seventy-eight cases of classical heat stroke (HS) seen during the summer of 1988 and 1989 have been evaluated. The diagnosis was established on the basis of classically accepted criteria (severe hyperthermia, impairment of the level of consciousness, anhydrosis, exposure to high environmental temperature). 62.8% of patients were females, with a mean age of 75 +/- 12.3 years. All patients had predisposing factors and 57.7% was taking facilitating drugs. 86% of the patients had 2 or more predisposing or facilitating factors. In 45 cases there were prodromic features. The suspicion of HS was not raised in any of the referring services. Hyperglycemia was present in 89.7% of cases, increased blood urea in 85.9%, high creatine kinase in 74.3%, abnormal coagulation in 52.9%, hypernatremia in 46.2%, hyponatremia in 37.2%, hypokalemia in 35.9%, hyperkalemia in 23.1%, metabolic acidosis in 41.1% and respiratory alkalosis in 36.9%. Electrocardiogram was abnormal in 95.4%. 31 patients (39.7%) died. Death was more common in patients with deep coma, shock, and higher blood urea levels. The present study demonstrates the occurrence of this condition in our area.

Stereospecificity of hydrogen transfer by bovine testicular 20 alpha-hydroxysteroid dehydrogenase

The stereospecificity of hydrogen transfer between steroid (17-hydroxyprogesterone) and both natural cofactors by bovine testicular 20 alpha-hydroxysteroid dehydrogenase (20 alpha-HSD) has been determined. Cofactors used in these studies, [4-pro-S-3H]NADH ([4B-3H]NADH) and [4-pro-S-3H]NADPH ([4B-3H]NADPH) were generated with human placental estradiol 17 beta-dehydrogenase (EC 1.1.1.62) utilizing [17 alpha-3H]estradiol-17 beta and NAD+ or NADP+, respectively. The resulting [4B-3H]NADH and [4B-3H]NADPH were purified by ion-exchange chromatography and separately incubated with molar excess of 17-hydroxyprogesterone as substrate in the presence of 20 alpha-HSD. Following incubation, steroid reactant and product were extracted, separated by HPLC and quantitated as to mass and content of tritium. The oxidized and reduced cofactors were separated by ion-exchange chromatography and quantitated as to mass and tritium content. In all incubations, equimolar amounts of 17,20 alpha-dihydroxy-4-pregnen-3-one and oxidized cofactor were obtained. Further, all recovered radioactivity remained with cofactor and none was found in the steroid product. In additional experiments, both reduced cofactors were separately incubated with glutamate dehydrogenase, an enzyme known to transfer from the B-side of the nicotinamide ring. Here radioactivity was present only in the unreacted cofactor fractions and in the product, glutamic acid. The results indicate that bovine testicular 20 alpha-HSD catalyzes transfer of the 4A-hydrogen from the dihydronicotinamide moiety of the reduced cofactor. Finally, this work described modifications that represent considerable improvement in the purification and assay of bovine 20 alpha-HSD as originally described.

Brain-stem auditory evoked potentials in squirrel monkey (Saimiri sciureus)

To more fully characterize brain-stem auditory evoked potentials (BAEPs) in non-human primates, BAEPs were recorded from chronically implanted epidural electrodes in 10 squirrel monkeys (Saimiri sciureus). The effects of stimulus intensity, repetition rate, and anesthesia (ketamine 20 mg/kg i.m.) on peak latencies and inter-peak intervals were evaluated. Monkey wave forms consisted of approximately 7 peaks (I-VII), each exhibiting similar latencies across sessions, with later peaks exhibiting greater variability. In some subjects, additional peaks (IIa, IIIa) and slow potentials were recorded. The slow potentials provided a substratum for peaks IV through VII. As with human, monkey peaks exhibited systematic changes in latency with changes in stimulus intensity or repetition rate. These shifts included significant decreases in latency with increasing intensity for peaks I-IV and increases in latency with increases in repetition rate for peaks III, V, and VI. Inter-peak intervals were similar to those observed in human. Furthermore, ketamine anesthesia significantly delayed the latencies of most peaks (except I, V, and VII). Some differences between monkey and human BAEPs were evident in the relative amplitude of specific peaks. For example, peak V is typically most prominent in human, while this was true for peak III in monkey. The similarities between unanesthetized monkey and human inter-peak intervals suggest that the times required for impulses to reach particular brain-stem areas are conserved across primate species that vary in brain size. This supports the hypothesis that comparably numbered BAEP peaks in monkey and human index homologous processes. The data also suggest that the differences between animal and human BAEPs commonly reported may result from the use of anesthetics. In summary, unanesthetized monkey BAEPs resemble human BAEPs in morphology, number of peaks, polarity, latency variability, inter-peak intervals, slow potentials superimposed on the high-frequency peaks, and variations in morphology, amplitude, and resolution of peaks as a function of recording site. Thus, unanesthetized monkey BAEPs may be an excellent model for investigating the neural substrates of human BAEP or for determining species differences in acoustic processing among primates.

[Serum and immunological markers of progression to acquired immunodeficiency syndrome in hemophiliacs]

In a cohort of 30 randomly selected hemophiliacs who were prospectively controlled for four years the predictive value of AIDS development was evaluated for serum markers of HIV infection and for lymphocytic subpopulations in peripheral blood. The patients were evaluated with a mean of 15.79 +/- 5.74 months, and overall antibodies, specific antibodies (anti-ENV and anti-p24), HIV antigen (Ag HIV) and lymphocyte subpopulations were determined. 50% of the hemophiliacs with positive serum Ag HIV (2/4) developed AIDS during the study, whereas this progression was not recorded in any anti-HIV positive, nonantigenic patient. The presence of Ag-HIV was detected at least two years before the diagnosis in these patients, and it was associated with the absence of anti-p24 in one or more determinations. The immune regulation parameters were not significantly different, at the beginning of the study, in the hemophiliacs who developed AIDS and in those who did not. However, the progression to AIDS was associated with a significantly smaller T4/T8 ratio at least one year before the diagnosis. Our results show that the development of AIDS in hemophiliacs is associated both with the presence of Ag-HIV in the serum and a reduction in the T4/T8 ratio, although the detection of the former appears to be earlier than that of the latter in this risk group.

Predictive value of the presence of P24 antigen in persons with antibodies to human immunodeficiency virus in Spain

In a prospective study of 37 individuals in Spain who did not have AIDS or AIDS-related complex but were positive for antibody to HIV, 164 sequentially taken serum samples were tested for the presence of the p24 antigen of HIV. Six of the subjects were antigenemic at entry to the study and five of the remaining 31 subjects seroconverted for HIV antigen during follow-up. Six (55%) of the 11 antigenemic patients but none of those without antigenemia developed AIDS. The interval from the time of first detection of HIV antigen to the diagnosis of AIDS varied greatly. The results confirm that individuals with HIV antigenemia run a significantly higher risk of developing AIDS.

Effects of locus coeruleus lesions on auditory, long-latency, event-related potentials in monkey

It has previously been demonstrated that monkeys exhibit certain event-related potential (ERP) components showing latency, polarity, and contingency similarities to those observed in humans. In the present study, monkey P300-like components were studied in order to evaluate the hypothesis that the noradrenergic locus coeruleus (LC) system participates in their generation or modulation. ERPs were recorded from untrained squirrel monkeys (Saimiri sciureus) twice a week for 4 weeks before and after bilateral LC lesions and interruption of dorsal bundle (DB) fibers. Stimuli consisted of 2 and 6 kHz tone pips (40 msec duration, 60 dB above nHL) presented once a second in random order. In most sessions, one tone constituted 90% of the stimuli and the other tone 10%, while in some sessions tones were made equiprobable to test the effects of manipulating stimulus probability. LC and DB lesions were made by first localizing the nucleus and creating an electrolytic lesion. Then, the electrode was placed at the anterior pole of the nucleus and a knife cut effected. The extent of damage to LC perikarya and ascending axons was assessed by reconstructing lesions from Nissl-stained sagittal sections through the brain stems. The effect of lesions on cortical noradrenergic axons was immunohistochemically verified utilizing antisera directed against dopamine-B-hydroxylase and tyrosine hydroxylase to label noradrenergic and dopaminergic axons, respectively. The prelesion ERP results replicated previous findings of P300-like components recorded in response to low-probability tones. The postlesion ERP data indicated that following damage to LC cell bodies, combined with interruption of histochemically detectable ascending noradrenergic axons, monkey P300-like potentials exhibited decreased areas, altered brain-surface distribution, and reduced sensitivity to stimulus probability. The correlation between the extent of cell body lesions and percentage reduction in the magnitude of P300-like responses was significant. However, interruption of DB fibers alone did not have similar effects. Neither type of lesion had any effect on amplitudes, latencies, or brain-surface distributions of P52, P172, or N250-900. There was, however, a significant effect on N106. Stimulus probability effects on the frontally distributed P52 and N106 were not altered by the lesions. These data support the hypothesis that the integrity of the LC nucleus and its ascending fibers is important in the generation and modulation of surface-recorded P300-like activity.

Endogenous event-related potentials in monkey: the role of task relevance, stimulus probability, and behavioral response

Monkeys were trained in auditory discrimination tasks resembling human paradigms in which long-latency endogenous components, such as P300, are typically recorded. Morphological, topographical, and functional properties of the monkey event-related potentials (ERPs) were analyzed to determine similarities and differences with human ERPs reported in the literature. ERPs were recorded from epidural electrodes in monkeys trained to produce operant responses. In a conditional discrimination (CD) task, tone pips (2 kHz or 6 kHz, 40 msec duration, and 60 dB above nHL) were presented every 4-8 sec. Target tones presented during 'time-in' (TI) were rewarded when followed by a response in the correct post-stimulus interval (400-3000 msec). In contrast, tones presented during 'time-out' (TO) were not rewarded. Under both conditions, tones elicited an initial frontally dominant triphasic complex (P56-N92-P157). Additionally, TI target tones followed by a response elicited a large negativity (N358) having maximal amplitude over mid-frontal regions and followed by a parietally distributed positivity (P658). The scalp distribution and covariation with task requirements of N358 resemble those reported for the human 'O' wave. ERPs were also recorded in an auditory oddball paradigm in which tone pips (2 kHz and 6 kHz, 40 msec duration, and 60 dB above nHL) were presented in random order every second. Monkeys trained in the CD paradigm, along with additional subjects, were trained to make delayed responses following target tones embedded in a background of different-pitch tones. Tone probabilities were varied in different sessions from 90-10, 70-30, to 50-50 to assess the effects of probability. Background and target tones elicited a triphasic complex (P52-N110-P159) similar in latency and distribution to that recorded in the CD task. Additionally, target tones in this paradigm elicited a long-latency positive component (LPC) that exhibited an inverse relationship with stimulus probability. LPC had an onset latency of approximately 150-200 msec, a duration of approximately 300 msec, and multiple peaks (P244 and P376). These data indicate the importance of stimulus context in eliciting long-latency endogenous activity. It further suggests that strong analogies exist between monkey and human potentials recorded under similar paradigms. The effects of task relevance, stimulus probability, and the act of producing behavioral responses are similar to the effects of these variables on analogous human potentials.(ABSTRACT TRUNCATED AT 400 WORDS)

Prevention of post-transfusion non-A, non-B hepatitis by non-specific immunoglobulin in heart surgery patients

To evaluate the effectiveness of immune serum globulin (ISG) in preventing non-A, non-B hepatitis, 291 heart surgery patients who received blood from voluntary donors were randomly assigned to receive either ISG or no additional protection. ISG was given intramuscularly before and 1 week after transfusion. 98 controls and 100 in the ISG group completed the study. Post-transfusion non-A, non-B hepatitis developed in 11 (11.2%) controls but in only 3 (3.0%) of the ISG group (p = 0.0203). 8 (72.7%) of control group with hepatitis had symptoms, and in 5 (45.4%) the disease became chronic. The disease was self-limiting in all 3 ISG patients affected, and only 1 of them had symptoms. Among those with non-A, non-B hepatitis aminotransferase levels were higher in the controls than in the ISG patients. Incubation periods longer than 8 weeks correlated with a tendency for the disease to become chronic. ISG recipients had shorter as well as more homogeneous incubation periods. ISG could be a safe, low-cost means for preventing post-transfusion non-A, non-B hepatitis which does not call for the discarding of donated blood.

Long-latency event-related potentials in squirrel monkeys: further characterization of wave form morphology, topography, and functional properties

Event-related potentials (ERPs) were recorded from the brain surface of untrained monkeys exposed to sequences of auditory stimuli (2 kHz and 6 kHz tones of 40 msec duration). Stimulus probability and interstimulus interval (ISI) were systematically varied in different paradigms. In an oddball paradigm with a 1 sec ISI in which one stimulus constituted 90% of all trials and the other 10%, a 'monkey' late positive component (MLPC), characterized by two peaks (P248 and P369), was recorded prominently over lateral parietal areas in response to the unpredictable and infrequent shifts in pitch. The amplitude of this late positivity was found to be sensitive to stimulus probability and to exhibit trial-to-trial sequential dependencies similar to those described for the human P300. The amplitude of MLPC was also found to be larger following longer ISIs. In addition, a 'monkey' late negative component (MLNC), with characteristics similar to those of the human slow wave (SW), was recorded following the infrequent shifts in pitch and found to temporally overlap with MLPC. MLNC was recorded with maximal amplitude over frontal cortex and was sensitive to stimulus probability but not to trial-to-trial changes in stimulus sequence. Thus MLPC and MLNC which appear to reflect similar yet distinct processes exhibit several analogies to the human P3a and SW, respectively.