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CD4+ T cells from mice with murine AIDS (MAIDS) have been shown to be unable to respond to TCR stimulation as measured by proliferation, IL-2 production, or IL-2R upregulation, although responsiveness was restored with PMA and ionomycin. In this report we have demonstrated that the inability of MAIDS CD4+ T cells to respond to CD3 stimulation was not associated with reduced surface expression of CD3, CD4, or CD28 and could not be overcome by costimulation with anti-CD28 antibody. However, MAIDS CD4+ T cells failed to activate the PIP2 hydrolysis pathway efficiently, resulting in diminished IP3 production and reduced Ca2+ mobilization compared to normal controls. Additionally, TCR signaling in MAIDS resulted in a reduction in the level of tyrosine phosphorylation of some proteins including deficient tyrosine phosphorylation of PLC-gamma 1, compared to normal CD4+ T cells. These studies suggest that stimulation through the TCR in CD4+ T cells from MAIDS-infected mice is uncoupled from the phosphotidylinositol hydrolysis pathway due to deficient activation of PLC-gamma 1.

The effects of murine AIDS infection on endogenous antioxidant defenses in mice fed the AIN-76A liquid diet were investigated. C57BL/6 female mice were divided into 2 groups: one group was injected interperitoneally with LP-BM5 murine retrovirus (MAIDS) stock, and the other group served as the non-infected control. Two weeks after the infection, the mice were killed and livers were excised for biochemical analysis of the antioxidant defenses. Liver reduced glutathione (GSH) levels and activities of both cytosolic superoxide dismutase (SOD) and mitochondrial SOD were significantly depressed by MAIDS infection. Activities of glutathione reductase (GR) selenium (Se)-dependent glutathione peroxidase (GPx), catalase and glutathione-S-transferase (GST) toward 1-chloro-2,4-dinitrobenzene (CDNB) were not affected by MAIDS infection. A previous study by this laboratory using the Lieber-DeCarli (L-D) all purpose liquid diet caused a decline in total SOD activity and GPx activity, but not GSH levels. The results suggest that MAIDS infection depresses liver antioxidant defenses; however, MAIDS infection of mice fed the AID-76A liquid diet depresses different liver antioxidant defense parameters when compared to those of the mice fed the L-D all purpose liquid diet.

The effects of chronic alcohol (EtOH) ingestion on antioxidant defenses in mice fed AIN-76A liquid diets were investigated. C57Bl/6 female mice were divided into three groups and fed the AIN-76A liquid EtOH diet containing EtOH to provide 31% of total caloric intake (TCI), the same basic diet containing EtOH to provide 35% of TCI, or an isocaloric AIN-76A liquid control diet. After 3 weeks, the mice were killed and livers were excised for biochemical analysis. Liver reduced glutathione (GSH) levels, and activities of both Mn-superoxide dismutase (SOD) and Cu/Zn-SOD were significantly decreased by both levels of EtOH. Activities of catalase and glutathione transferase (GT) were significantly increased, whereas glutathione peroxidase (GP) activity was not affected by either level of EtOH. Our previous study using the Lieber-DeCarli liquid EtOH diet caused a decline of total SOD and GP activities. The results suggest that chronic EtOH administration decreases liver antioxidant defenses; however, the mice fed the AIN-76A EtOH liquid diet can maintain a higher antioxidant defense capability than those fed Lieber-DeCarli EtOH liquid diet.

Chronic ethanol (EtOH) abuse in humans leads to a variety of immunomodulatory events that can alter resistance to a number of infectious agents. Whether alcohol abuse affects the susceptibility to human immunodeficiency virus infection or the subsequent development of acquired immune deficiency syndrome (AIDS) is a matter of extreme importance; however, available information in humans or animal models is limited. The goal of this study was to evaluate the effect of chronic EtOH feeding in mice on the development of immunodeficiency in the murine model of AIDS (MAIDS). C57BI/6 mice were placed on the Lieber-DeCarli liquid EtOH diet (25% or 31% total caloric intake) or a nutrient-matched isocaloric liquid control diet. Seven days later, mice were infected with the LP-BM5 murine leukemia virus mixture, and groups of infected and noninfected mice were assayed at defined time points postinfection for antigen-specific and nonspecific immune responses. In the absence of retroviral infection, chronic EtOH feeding (5-8 weeks) led to reductions in spleen weights, compared with isocaloric controls. In spite of reduced spleen size, mitogenic responses of spleen cells to concanavalin A (ConA) and lipopolysaccharide (LPS) were elevated in EtOH-fed mice, as compared with mice fed the control diet. Chronic EtOH feeding also enhanced the allogeneic mixed lymphocyte response and increased antigen-specific priming of both B-cells and CD4+ T-cells to the antigen, sheep red blood cells. In MAIDS-infected mice, chronic EtOH feeding delayed but did not prevent the onset of virus-induced immunodeficiency and MAIDS-induced autoantibody synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Tumor necrosis factor-alpha (TNF-alpha) is a mediator of liver injury. The objective of this study was to develop an in vitro model of TNF-mediated liver cell injury using the Hep G2 cell line. Hep G2 cells normally are insensitive to TNF cytotoxicity, but they were rendered susceptible, or sensitized, to TNF cytotoxicity by inhibitors of RNA and protein synthesis. The concentration of TNF required to kill 50% of Hep G2 cells sensitized with 0.8 mumol/L actinomycin D (Act D) was 35 pmol/L compared with 5 pmol/L for LM fibroblasts, a classic target cell used in TNF cytotoxicity bioassays. Similarly, TNF cytotoxicity occurred in Hep G2 cells sensitized with cycloheximide (CHX), and cytotoxicity to both inhibitors was dose dependent. Both protein and RNA synthesis were inhibited in Hep G2 cells by the concentrations of CHX and Act D associated with TNF cytotoxicity. Hep G2 cells pretreated with TNF alone and later exposed to normally toxic concentrations of TNF with DACT did not develop cytotoxicity. Thus, in vitro tolerance to TNF was induced. Cytotoxicity also was more severe at modestly increased temperatures (39 degrees C versus 37 degrees C), which may have clinical relevance to hepatic decompensation during febrile episodes. We suggest that the Hep G2 cell line sensitized by inhibiting RNA and protein synthesis is a useful in vitro model for evaluating mechanism(s) of TNF-mediated liver cell injury.

This controlled parent-targeted drug prevention intervention followed two cohorts of students to determine the effect of encouraging parents to intervene in risk factors for adolescent tobacco and alcohol use. Suggestions included limiting association with substance-using peers and asking parents to limit adolescent access to alcohol. Although student participation and retention in the study was good parent participation was poor. Parents were unlikely to know whether their children had substance-using friends and there was no impact on adolescent substance use. However, parent monitoring of children's whereabouts, maintaining high rapport and a respectful parent-child relationship did protect against adolescent substance use. Future parent-targeted prevention programs should target protective factors, rather than trying to control risk factors.

According to most mental health statutes in force around the world, doctors may involuntarily treat only acutely psychotic patients who present some danger to themselves, others or property. Chronic patients who, owing to volitional or cognitive defects, present a similar danger may not be thus treated. This may cause situations to arise where dangerous chronically ill patients who refuse treatment may cause serious harm because of physicians' inability to treat them. This article suggests changes to contemporary mental health statutes, in line with Judaic Halachic codes, which view all mentally ill patients as potentially harmful, and require physicians to treat--voluntarily or involuntarily--all mentally ill persons.

This study reports the level of participation of parents in a parent-targeted school-based drug prevention program, the differences between students whose parents participate and those who don't, and the implications for involving parents in future drug prevention programs. Among 1761 eligible seventh grade families, 1263 students (72%) and 1142 parents (65%) completed surveys assessing the quality of parent-child relationships as well as tobacco and alcohol use. Ten percent of eligible families attended at least one of the evening sessions. Compared to students whose parents completed the survey, students whose parents did not complete a survey were more likely to report they used tobacco, had more friends who used substances, were monitored less by their parents, had more risk-taking behaviors, had lower grade-point averages, and their parents had higher rates of tobacco and alcohol use. Parents who attended evening sessions had the lowest rates of tobacco use and reported spending the most time with their children. Parent-targeted drug preventions programs may stigmatize attending parents and may be unlikely to attract the highest risk families.

In light of the ability of B cells treated with neuraminidase to interact more effectively with T cells, the increased capacity of activated, but not small resting B cells, to interact with T cells could be associated with the level of sialylation on certain B cell surface molecules which influences the effectiveness of the physical interaction between B and T cells. The purpose of this study was to determine if activation of B cells altered sialylation via an endogenous sialidase which affected both the initial interaction between T and B cells and subsequent B cell-induced T cell proliferation. The competitive neuraminidase inhibitor, 2-deoxy-2,3-dehydro-N-acetylneuraminic acid (NeuAc2en), inhibited LPS-mediated enhancement of B cell conjugate formation with Ia-specific T cell clones as well as enhancement of their capacity to stimulate a mixed lymphocyte reaction. The addition of NeuAc2en during LPS stimulation did not affect the surface expression of Ia, LFA-1, ICAM-1 or mB7, suggesting that inhibition of LPS-mediated enhancement by the sialidase inhibitor was not due to changes in the level of expression of the major B cell adhesion or co-stimulatory molecules. Short term stimulation with phorbol myristate acetate (PMA) and ionomycin also enhanced the ability of resting B cells to form antigen specific T:B conjugates. However, activation of B cells with PMA and ionomycin or with LPS did not change the capacity of a sialic acid specific lectin to bind to the B cells, suggesting that activation was not associated with global changes in surface sialic acid content. B cell stimulation did not appear to increase the activity of the most prevalent B cell sialidase activity as measured in an in vitro assay system, suggesting that the major B cell sialidase may not be responsible for the alteration of B cell sialylation levels or the ability of activated B cells to interact more effectively with T cells. The possibility of intracellular compartmentalization of sialidase activity or that a minor B cell sialidase may play a role in the regulation of a B cells ability to interact with T cells are discussed.

Objective: To identify which specific parenting behaviors are associated with the onset of alcohol and tobacco use and how they are associated., Design: Prospective cohort study of two groups of preadolescents surveyed annually, the first group for 4 years, the second for 3 years., Setting: Two public school districts in Southern California., Subjects: 1034 fifth graders and 1266 seventh graders began the study after obtaining parental consent to complete surveys in a classroom setting. By the last measurement, attrition was 37 and 38% for the two cohorts, respectively., Main Outcome Measures: The onset of tobacco or alcohol use in the last month., Results: Children who reported that parents spent more time with them and communicated with them more frequently had lower onset rates of using alcohol and tobacco in the last month. These parental interactions lead to more positive relationships with their children. Parental monitoring and positive relations were protective factors for disruptive behavior and the selection of substance-using friends. Disruptive behavior increased the odds of adolescents drinking in the last month approximately twofold and of smoking in the last month two to fourfold., Conclusions: This study provides further evidence that parenting behaviors are significant precursors to adolescent disruptive behavior, vulnerability to peer pressure, and subsequent substance use. Parents should be targeted in future substance use prevention programs, before their children reach adolescence.

Rapidly accumulating evidence suggests that a proportion of patients with acquired immunodeficiency syndrome (AIDS) develop hypertensive pulmonary vascular disease reminiscent of primary pulmonary hypertension. As an initial step to explore the link between AIDS and hypertensive pulmonary vascular disease, the present study determined whether pulmonary hypertension is present in a well-characterized murine model of retrovirus-induced immunodeficiency. In agreement with previous reports, mice infected with the LP-BM5 murine leukemia virus developed polyclonal B and T cell activation followed by progressive and severe B and T cell immunodeficiency. At 12 wk postinfection, when persistent immunodeficiency was established, mice were anesthetized, and right ventricular systolic pressure was determined in open-chest, mechanically ventilated animals. Mean right ventricular systolic pressure was 14.7 +/- 1.3 mm Hg in control animals and was increased significantly to 22.5 +/- 3.2 mm Hg in virus-infected mice. Right ventricular hypertrophy was also present in infected mice as evidenced by a 27% increase in the ratio of right to left ventricular weights; there were no group-dependent differences in the left ventricular to total-body weight ratio. Morphometric evaluation indicated that medial thickness in muscularized pulmonary arteries, expressed as a percentage of the external diameter, was 9.6 +/- 0.4% in control lungs and increased to 14.4 +/- 0.5% in lungs from infected animals. Qualitative histopathologic analysis suggested increased perivascular collagen deposition in lungs from infected animals relative to control animals. Unlike AIDS patients with pulmonary hypertension, infected mice did not exhibit plexiform lesions or intimal fibrosis of the pulmonary arteries.(ABSTRACT TRUNCATED AT 250 WORDS)

Regulation of IL-2 gene expression in response to receptor-mediated stimuli is known to be mediated primarily by the IL-2 transcriptional enhancer and multiple transcription factors. However, the mechanism that controls the differential expression of the IL-2 gene in both human and murine CD4+ Th cell subsets (Th1-IL-2+ and Th2-IL-2-) is not clearly understood. Differential IL-2 gene expression was assessed in murine Th1 and Th2 subsets by analyzing the expression of a Escherichia coli lacZ reporter gene under control of the human IL-2 enhancer (IL2ZH) transfected in both T cell subsets. Stimulation of transfected T cells with the mitogen Con A, anti-CD3 Ab, or PMA plus ionomycin activated the IL2ZH construct in Th1 but not Th2 cells. However, IL2ZH was activated in stimulated Th2 cells that were co-transfected with a vector that overexpressed the eukaryotic initiation factor 4E (eIF-4E). It has been shown that eIF-4E is rate limiting for protein synthesis and its overexpression leads to increased rates of protein synthesis. Hence, eIF-4E overexpression could have overcome a deficiency in transcriptionally active levels of IL-2 regulatory factors in Th2 cells leading to IL-2 enhancer activation. This possibility was supported by demonstrating that transcriptionally active levels of the critical IL-2 transcription factor, nuclear factor of activated T cells (NF-AT), occurred only in Th2 cells overexpressing eIF-4E but not in normal Th2 cells, thus indicating that the inability of Th2 cells to express IL-2 was associated with inadequate levels of at least one transcription factor, NF-AT. Moreover, these results were confirmed by the observation that eIF-4E overexpression augmented NF-AT binding activity in Th2 cells. These data suggest that concentrations of inducible transcription factors are a major component of the regulatory mechanisms dictating IL-2 expression and may be under translational control in Th1/Th2 T cell subsets.

1. Five hundred ninety-five single neurons with tactile receptive fields (RFs) on the contralateral arm were isolated in the primary somatosensory cortex (SI) of awake, behaving monkeys. 2. Fifty-eight percent of the tactile cells showed significantly different levels of activity during active movements of the arm in eight directions or during active maintenance of the arm over the target endpoints. 3. The discharge of many of the active tactile cells was unimodally tuned with movement direction and the pattern of the tactile population activity varied in a meaningful fashion with arm movement direction and posture. 4. The intensity of the arm-movement-induced activity was typically less than that evoked by direct tactile stimulation of the cell's RF. 5. The probability of task-related activity was correlated with certain RF properties, in particular the sensitivity of the cell to lateral stretch of the skin and to passive arm movements that avoided direct contact of the RF on any surface. 6. This suggests that task-related activity results mainly from the activation of tactile receptors by mechanical deformation of the skin as the arm changes geometry during movement. 7. These results demonstrate that tactile activity containing potential proprioceptive information is generated in SI during active arm movements that avoid direct contact of the skin with external surfaces. Whether or not this input contributes to the kinesthetic sensations evoked by the movements cannot be resolved by this study.

1. Cells were recorded in areas 3b and 1 of the primary somatosensory cortex (SI) of three monkeys during active arm movements. Successful reconstructions were made of 46 microelectrode penetrations, and 298 cells with tactile receptive fields (RFs) were located as to cytoarchitectonic area, lamina, or both. 2. Area 3b contained a greater proportion of cells with slowly adapting responses to tactile stimuli and fewer cells with deep modality inputs than did area 1. Area 3b also showed a greater level of movement-related modulation in tactile activity than area 1. Other cell properties were equally distributed in the two areas. 3. The distribution of cells with low-threshold tactile RFs that also responded to lateral stretch of the skin or to passive arm movements was skewed toward deeper laminae than for tactile cells that did not respond to those manipulations. 4. The variation of activity of tactile neurons during arm movements in different directions was weaker in the superficial laminae than in deeper cortical laminae. 5. Cells with only increases in activity during arm movements were preferentially but not exclusively located in middle and superficial layers. Cells with reciprocal responses were found mainly in laminae III and V, whereas cells with only decreases in activity were concentrated in lamina V. 6. Overall, active arm movements evoke directionally tuned tactile and "deep" activity in areas 3b and 1, in particular in the deeper cortical laminae that are the source of the descending output pathways from SI.

The mechanism by which CD4+ T cells are depleted during HIV infection remains a matter of controversy. Recent reports have suggested that activation-induced apoptosis of antigen-specific CD4+ T cells may lead ultimately to depletion of this T cell subset during HIV infection. The murine retroviral model of AIDS (MAIDS) also displays progressive immunodeficiency, but depletion of the CD4+ T cell subset is not characteristic of the disease. We report that a fraction of splenic CD4+ T cells from 8- to 14-week MAIDS-infected C57B1/6 mice, but not normal mice, was undergoing apoptosis at the time of cell isolation. Typical apoptotic morphology and internucleosomal DNA fragmentation was seen in CD4+ T cells only from infected mice. Moreover, injection of anti-CD3 mAb enhanced DNA fragmentation in CD4+ T cells from infected but not normal mice, suggesting that the apoptosis in vivo in CD4+ T cells during MAIDS may be dependent on cell activation. Induction of apoptosis was associated with defective signaling through the TcR complex, since anti-CD3 stimulation in vitro of CD4+ T cells from infected mice caused a diminished calcium response, yet no cellular proliferation. Despite the occurrence of apoptosis in vivo in CD4+ T cells from MAIDS-infected mice, CD4+ T cells were not depleted during the course of disease. Thus, while apoptosis in CD4+ T cells is a characteristic of MAIDS immunodeficiency disease as well as HIV infections in humans, CD4+ T cell depletion is only observed in HIV infections. In view of the extensive lymphocyte expansion which occurs in vivo in MAIDS, the balance between activation-induced apoptosis and chronic cell proliferation may determine whether cell depletion is a characteristic feature of retrovirus-induced immunodeficiencies.

Whether ethanol (ETOH) abuse could contribute to the development of acquired immunodeficiency syndrome (AIDS) among human immunodeficiency virus (HIV)-positive drug abusers is a critical question for which little experimental information is available. This study was designed to determine if chronic ETOH feeding and murine AIDS virus infection cooperatively affected liver antioxidant defense systems in C57B1/6 female mice. Mice were divided into two groups and fed the Lieber-DeCarli liquid ETOH diet containing ETOH at a concentration to provide 31% of total caloric intake or an isocaloric liquid control (control) diet in which dextrin-maltose replaced ETOH. One week after the initiation of ETOH feeding, half of the mice in each diet group (8 mice) were injected intraperitoneally with murine retrovirus (MAIDS) stock. After 3 and 5 weeks of ETOH feeding, half of the mice in each of the four treatment groups (4 mice) were killed, and livers were excised for biochemical analysis. Liver reduced glutathione (GSH) levels and activities of glutathione peroxidase (GP), glutathione reductase (GR), glutathione transferase (GT), catalase and superoxide dismutase (SOD), and serum ETOH concentrations were determined. The results demonstrated that serum ETOH concentrations were significantly elevated in ETOH-MAIDS group when compared with the ETOH group. Moreover, chronic ETOH feeding and MAIDS infection independently depressed liver antioxidant defense capability, and together led to an additive inhibition of GSH and SOD activities. In addition, MAIDS infection inhibited an ETOH-induced increase in catalase and GT activities. These results suggest that alcohol abuse could contribute to the development of AIDS by inhibiting the protective capability of an infected individual against oxidative stress.(ABSTRACT TRUNCATED AT 250 WORDS)

An intervention was developed to promote safer sex and condom use among patients seeking treatment for sexually transmitted disease (STD) at a public health STD clinic in Los Angeles, CA. The intervention consisted of a short group discussion on condom use, a presentation of a videotape portraying condom use as socially acceptable behavior, and a role-playing session concerning negotiating the use of a condom with one's sex partner. The study group was 551 persons who visited the clinic in 1988. Medical records of 426 (77 percent) were located and reviewed 7 to 9 months later. Among those, 220 had participated in the intervention and 206 were control subjects who had not participated in the intervention. The rates at which patients reacquired STD after treatment and after the intervention were compared between the intervention group and the control group. Men who participated in the intervention subsequently showed a lower rate of STD reinfection than those who did not. There was no evidence that the intervention reduced reinfection among women. The strongest predictor of reinfection was found to be a history of STD infection prior to the infection that was being treated at the time of the intervention. The results show that group interventions directed to STD patients can be effective in reducing STD reinfection among men.

In 1986 the rate of infectious syphilis (primary and secondary) in Los Angeles County began to rise from previously stable levels of about 23.5 per 100,000 to peak at 55.6 per 100,000 in 1987. The incidence of congenital syphilis increased from 205 cases in 1987 to 575 cases in 1989. The county's Sexually Transmitted Disease Program instituted a disease-specific plan to address the epidemic. Factors considered in designing the program included the high morbidity and mortality associated with congenital infection, the existence of latent infection, self-limiting symptoms, and the availability of an inexpensive screening test and curative treatment. Policy changes implemented comprised expanded screening, expanded surveillance, increased contact tracing, and the initiation of condom promotion programs. To evaluate the relative effectiveness of Los Angeles County's syphilis control efforts, the epidemic curve for infectious syphilis was compared with trends in other urban areas. Although the rate of infectious syphilis climbed a year earlier in Los Angeles than in other cities, it returned to baseline levels when other cities' rates remained at epidemic levels.

Three different brief intervention programs to promote condom use were tested among patients in inner-city sexually transmitted disease (STD) clinics. The first, "Condom Skills," focused on teaching mechanical aspects of how to use a condom. The second, "Social Influences," emphasized how to negotiate condom use with one's sexual partner. The third, "Distribution," provided patients with an unlimited number of free condoms, retrievable at local community businesses. Of the 903 subjects whose medical records were reviewed after exposure to the intervention programs, evidence of continued unsafe sexual behavior, documented by subsequent treatment for a new STD, was found for 12.6% of the women and 19.9% of the men. When compared with male control subjects, male study patients had fewer documented subsequent STD reinfections. The relative risk (RR) and 95% confidence interval (CI) values were 0.48 and 0.28, 0.81 for the condom skills group; 0.65 and 0.40, 1.04 for the social influences group; and 0.85 and 0.56, 1.29 for the distribution group. There was no decrease in the incidence of STDs among female patients compared with control subjects; indeed, there was a trend toward increased risk of STDs among women exposed to the Social Influences intervention program. This study demonstrates that brief condom promotion programs can be effective for male STD patients, and that caution must be exercised in promoting condoms to women with a high risk of acquiring STDs. Further research on programs promoting safer sex among these women is needed.

The defective virus found in the LP-BM5 mixture of murine leukemia viruses induces a severe immune deficiency disease in C57BL/6 mice that is characterized by the activation and expansion of T and B cells that become unresponsive to normal immune stimuli. The nature of the biochemical lesion in these defective lymphocyte populations remains unknown. Flow cytometric analysis of the T cell population in infected animals has demonstrated expansion of both CD4+ and CD8+ subsets. Despite chronic expansion in vivo, CD4+ T cells by wk 4 postinfection failed to up-regulate cell surface IL-2R expression, produced IL-2, or proliferate in vitro in response to either Con A, Staphylococcal enterotoxin super-antigens, or anti-CD3 stimulation. Exogenous IL-2 did not restore the proliferative response and also failed to up-regulate IL-R expression on CD4+ T cells from infected mice, even though basal IL-2R expression was initially elevated compared to normals. In contrast, CD4+ T cells from infected mice could be induced to proliferate by stimulation with PMA and ionomycin resulting in IL-2R up-regulation, IL-2 production, and proliferation. Moreover, proliferation could also be induced by anti-CD3 plus PMA, although anti-CD3 plus ionomycin was without effect. These studies suggest that chronic expansion of CD4+ T cells in infected mice is probably not maintained by normal TCR signaling, which appears defective in these cells. In addition, the lesion in biochemical signaling appears to result in defective activation of protein kinase C, which can be overcome by direct activation with PMA.

Experiments were conducted with rats and mice to evaluate the effect of the consumption of endophyte (Acremonium coenophialum) and associated toxin(s) infected tall fescue on humoral and cellular aspects of immune function. Treatment diets were: (1) rodent chow (RC) or (2) rodent chow mixed 1:1 (w/w) with endophyte infected (E+) or (3) non-infected (E-) tall fescue seed. Rats fed the E+ diet in experiment 1 (43 days) exhibited a lower (P less than 0.05) serum titer to sheep red blood cell (SRBC) immunization than those fed the E- diet (38.4 vs 131.3). The E+ rats also had lower (P less than 0.01) white cell counts than either RC or E- groups (5225 vs 8959 and 7491/mm3). Spleen cells from mice fed the E+ diet for 37 days exhibited a reduced (P less than 0.05) response to the mitogens Concanavalin A and lipopolysaccharide. Flow cytometric analysis revealed a significant (P less than 0.01) 42% increase in T suppressor cell numbers in spleens of mice fed the E+ vs RC diets.

Reports of congenital syphilis in 1987 were reviewed to determine how new national guidelines for defining congenital syphilis would influence reported rates in Los Angeles County. After reviewing all reported reactive serologic tests for syphilis, we found 166 additional cases, resulting in a 426 percent increase in the 1987 reported rate of congenital syphilis. Rates of congenital syphilis are dependent upon surveillance practices, screening policies, and case definition.

A previous study reported that proximal-arm related area 5 neurons showed continuously-graded changes in activity during unloaded arm movements in different directions (Kalaska et al. 1983), which resembled the responses of primary motor cortex cells in several respects (Georgopoulos et al. 1982). We report here that loading the arm reveals an important difference between cell activity in the two areas. Loads were continuously applied to the arm in different directions. The loads produced large continuously-graded changes in muscle activity but did not alter the handpath or joint angle changes of the arm during the movements. The activity of most area 5 cells was only weakly affected by the loads, and the overall pattern of population activity was virtually unaltered under all load conditions. This indicates that area 5 activity encodes the invariant spatial parameters (kinematics) of the movements. In contrast, many motor cortex cells showed large changes in activity during loading, and so signal the changing forces, torques or muscle activity (movement dynamics; Kalaska et al. 1989).

The availability of paired homogeneous Ia+ tumour cell lines (P388AD, interleukin (IL)-1+, and P388NA, IL-1-), which differ in inducibility for IL-1, provided a unique opportunity to assess directly the role of Ia and IL-1 in the induction of cytolytic T cells (CTL) to trinitrophenol (TNP)-modified self. TNP-P388AD but not TNP-P388NA consistently induced H-2-restricted, hapten-specific CTL. However, in the presence of an exogenous source of IL-1, TNP-P388NA was able to induce CTL of the magnitude seen with TNP-P388AD. Both Ia expression and IL-1 secretion were necessary in that when TNP-modified purified T cells were utilized as stimulators, CTL activity was not demonstrated even if IL-1 was added, but was only seen when unmodified, P388AD, or spleen cells were added to the cultures.

The mechanism(s) of stress-induced hypoferremia and hypozincemia remains unclear. We studied the role of granulocytes and lactoferrin (LF) in endotoxin and murine interleukin 1 (IL-1)-induced depression of serum Fe and Zn concentrations in both rabbits and rats. Both endotoxin and IL-1 administration induced significant hypoferremia (P less than 0.01) and hypozincemia (P less than 0.01) after 6 h in both species. Granulocyte depletion before IL-1 infusion significantly (P less than 0.01) diminished the hypoferremia but not the hypozincemia. Moreover, infusion of 5 or 15 mg of human LF into rabbits caused significant hypoferremia (P less than 0.005) without hypozincemia. Significant hypozincemia (P less than 0.01) could only be demonstrated after a 75-mg infusion. In contrast, infusions of human transferrin at equivalent doses (5, 15, and 75 mg) induced neither hypoferremia nor hypozincemia. Therefore endotoxin and IL-1-induced hypoferremia and, to a much lesser degree, hypozincemia are granulocyte dependent. Granulocyte released LF is a specific carrier molecule for transport and removal of Fe from the circulation during the acute phase response. The data suggest a mechanistic dissociation of IL-1-induced hypoferremia and hypozincemia with LF-independent mechanisms for Zn.

The recognition of antigen-presenting cells (APCs) by T helper (TH) cells occurs in an antigen (Ag)-specific, MHC-restricted manner. Recent evidence, however, suggests that other interaction molecules may also be involved in TH:APC interaction in addition to the T-cell receptor (Ti) and class II or la antigens. We chose, therefore, to examine the role of various interaction molecules (Ia, Ti, L3T4, and LFA-1) in Ag presentation using several TH clones with distinct recognition patterns (self-Ia, self-Ia/Ag, and allogenic Ia). We describe here the use of a rapid clustering assay to study the initial binding events that occur between TH cells and APCs of various types. In all combinations of TH cells and APCs, conjugate formation was both Ag-specific and MHC-restricted. Moreover, with one exception cell clustering was prevented by the addition of monoclonal antibodies (mAb) against either the T-cell receptor or class II MHC molecules. In contrast, mAb to L3T4 and LFA-1 generally failed to inhibit cluster formation even though T-cell proliferation was profoundly inhibited. The relative importance of these interaction molecules in conjugate formation appeared to depend on the APC type as well as on the T-cell clone used. The implications of these findings for the mechanisms of Ag presentation and T-cell activation are discussed.

These experiments were designed to determine if separate subpopulations of T cells were involved in the syngeneic and allogeneic mixed lymphocyte reaction. Rat lymph node T cells were separated into W3/25+ and W3/25- subpopulations by panning with the monoclonal antibody W3/25 and tested for their ability to proliferate in both syngeneic (SMLR) and allogeneic (MLR) mixed lymphocyte responses, as well as to develop cytotoxicity against allogeneic, syngeneic, and trinitrophenol (TNP)-modified syngeneic targets. The W3/25+ T cells reacted strongly in the SMLR and the MLR whereas the W3/25- fraction proliferated only in response to allogeneic stimulation and with a kinetic pattern distinct from W3/25+. Furthermore, addition of W3/25 monoclonal antibody directly to the cultures was shown only to inhibit the proliferation of the W3/25+ T-cell fraction. The W3/25- subpopulation contained cytotoxic T cells (CTLs) against both allogeneic determinants and TNP-modified self. However the requirements for the activation of allospecific CTLs were distinct from those for CTLs for TNP-self in that W3/25- allospecific CTLs required no detectable help from W3/25+ T cells but generation of the CTL response against TNP-self required the presence of W3/25+ helper T cells (Th). These data suggest that in the rat, there exist subsets of T cells recognized by their cell surface phenotype that distinguish between self and nonself determinants and the requirements for activation are different for each of these populations.

Endotoxin depresses cytochrome P450 levels when injected into animals. The purpose of this study was to determine whether endotoxin itself, or monokine(s) released in response to endotoxin administration are responsible for this effect. Cytochrome P450 levels and drug metabolizing activities were measured in endotoxin resistant C3H/HeJ mice 24h after single intraperitoneal injections of either lipopolysaccharide (LPS), a semipurified murine monokine preparation containing interleukin-1 (IL-1), or murine recombinant IL-1. In endotoxin sensitive C3H/HeN mice, LPS (0.5 mg/Kg) decreased total cytochrome P450 levels, benzphetamine demethylase activities, and ethoxyresorufin-0-deethylase activities. This dose of LPS did not alter cytochrome P450 levels or activities in the C3H/HeJ mice. However, after injection of the semipurified monokine preparation or the recombinant IL-1, there were significant decreases in cytochrome P450 levels and activities similar to the decreases observed with LPS in the C3H/HeN mice. These findings suggest that the alterations in hepatic cytochrome P450 seen with endotoxin injection are mediated, at least in part, by IL-1.

The development of functional Fc receptors (FcR) during induced differentiation with the tumor promoter, phorbol myristate acetate (PMA), was studied in the murine tumor cell line, P388. PMA induced the appearance of FcR on the membranes of P388 cells as indicated by the binding of IgG-coated sheep red blood cells (IgG-SRBC). Concentrations of PMA as low as 1 ng/ml were sufficient to induce the expression of FcR as well as to inhibit cellular division and to induce adherence in the P388 tumor cell line; however, optimal FcR induction occurred at PMA concentrations of 10-100 ng/ml. Immunofluorescent analysis with heat-aggregated myeloma proteins indicated that PMA induced FcR which were capable of binding IgG2a and IgG2b immunoglobulins, but not IgG1. Adherence to a substratum was determined to be a second required signal for expression of FcR, since PMA induction of P388 tumor cells in teflon dishes failed to fully develop FcR and adherence of P388 cells to poly-L-lysine-coated culture dishes in the absence of PMA was insufficient for FcR expression. FcR which appeared after PMA induction were non-functional in the sense that membrane-bound IgG-SRBC were not ingested to any significant extent by the tumor cells. However, if FcR induction occurred in the presence conA-induced rat spleen cell culture supernatants, phagocytosis of membrane-bound erythrocytes occurred. These findings suggest that for the expression of FcR which are capable of particle internalization, at least three identifiable membrane-transmitted signals are required during differentiation.

Models for T cell:B cell collaboration suggest that activated B cells process and present Ag to Th cells which subsequently induce B cell proliferation and differentiation. In contrast to activated B cells, resting B cells have generally been shown to be less efficient APC. If this model of T:B collaboration is physiologically correct, then resting B cells must undergo a phenotypic change that permits effective interaction with T cells. In this report, the requirement for rapid signaling through surface Ig on resting B cells for the induction of T:B interaction was investigated with an in vitro clustering assay. Resting splenic B cells were unable to form specific conjugates with T cell clones, unless the B cells were first treated with neuraminidase to remove sialic acid. In contrast, LPS-activated B cells were able to form conjugates without prior treatment. The ability of antibody against LFA-1 or L3T4 to inhibit cluster formation depended on the state of B cell activation in that anti-LFA-1 and anti-L3T4 mAb inhibited cluster formation by neuraminidase-treated resting B cells, but not by LPS-activated B cells. In addition, Ag-specific B cells which were isolated by their capacity to bind specific Ag were able to form clusters without any additional treatment. Moreover, treatment of resting splenic B cells with anti-mu-antibody induced clustering potential in B cells in as little as 10 min, suggesting that signaling through surface Ig was sufficient to induce this phenotypic change in B cells. Furthermore, activation of protein kinase C and Ca2+ mobilization were shown to be involved in that PMA and ionomycin treatment were also able to induce clustering potential in resting B cells. The rapid induction of clustering potential in resting B cells after signaling through surface Ig may represent a fundamental change in B cell physiology which occurs after recognition of specific Ag and may be required for effective cognate recognition between resting hapten-specific B cells and carrier-specific T cells. The potential role of desialylation for the induction of T:B interaction is discussed.

A masculinized female infant was born to a mother who had virilizing signs dating from the fourth month of pregnancy. Serum 17 alpha-hydroxyprogesterone, dehydroepiandrosterone, and testosterone levels were all normal in the infant. Maternal testosterone level was markedly elevated one week post partum. Dexamethasone phosphate suppression was normal. Human chorionic gonadotropin stimulation five weeks post partum revealed further elevation of high baseline free and total testosterone levels. Free and total testosterone levels 30 weeks post partum were normal, and all maternal virilizing signs had regressed with the exception of her deepened voice. The child has had no progression of masculinization. The mother is believed to have had a luteoma of pregnancy.

Interleukin-1 (IL-1) is a monokine which has been demonstrated to produce a variety of seemingly diverse metabolic events including fever, neutrophilia, anorexia, altered mineral metabolism, muscle catabolism, and fibroblast proliferation. Because many of the clinical features of alcoholic hepatitis are metabolic abnormalities that have been shown to be caused by IL-1, we questioned whether patients with alcoholic hepatitis had elevated serum levels of IL-1. Six patients with alcoholic hepatitis had serum IL-1 activity measured by the thymocyte costimulator assay after serum inhibitors were removed. Their values were compared to those of 6 age and sex-matched healthy controls. Patients with alcoholic hepatitis had markedly elevated serum IL-1 activity, with the integrated value of all fractions having serum IL-1 activity being 9.8 times that of controls. IL-1 activity in serum from alcoholic hepatitis patients also was blocked by antibody to IL-1. We conclude that patients with alcoholic hepatitis have increased serum IL-1 activity which may play a role in certain of the metabolic complications of alcoholic hepatitis.

Interleukin-1 (IL-1) mediates components of the acute phase response, stimulates granulocyte metabolism, and induces endothelial cell surface changes. We studied in unanesthetized rabbits the effects of intravenous divided dose infusions of a murine monokine preparation containing IL-1 activity, on circulating granulocytes, their sequestration within the pulmonary microvasculature, pulmonary edema formation, and changes in pulmonary vascular permeability. Monokine administration induced significant (P less than 0.01) granulocytopenia as well as a significant (P less than 0.001) increase in mean alveolar septal wall granulocytes per high power field (HPF) compared with saline-injected controls. Infusions of the monokine preparation significantly (P less than 0.005) increased lung wet-to-dry weight ratios as well as significantly (P less than 0.025) increased pulmonary extravasation of radiolabeled albumin. Electron microscopic analysis of lung sections obtained from monokine-infused animals demonstrated endothelial injury, perivascular edema, and extravasation of an ultrastructural tracer. We conclude that a monokine preparation containing IL-1 activity can induce profound granulocytopenia, pulmonary leukostasis, and acute pulmonary vascular endothelial injury.

The ability of an adherent Ia+, interleukin 1+ (IL-1) tumor cell line (P388AD) to present turkey gamma-globulin (TGG) to primed T lymphocytes was demonstrated and compared with normal antigen-presenting cells (APC) found in mouse spleen. P388AD tumor cells presented TGG to long-term cultures of TGG-reactive T cells (LTTC) and to lymph node-derived T cells which were enriched on nylon wool columns and subsequently depleted of endogenous antigen-presenting cells with anti-Ia antisera and complement. MHC-restricted antigen presentation by P388AD was observed when long-term cultures of TGG-reactive T cells were used as the responding T-cell population. Furthermore, antisera directed against I-region determinants expressed on the P388AD tumor cells inhibited TGG-specific T-cell proliferation in a dose-related fashion, suggesting a functional role for the tumor cell-associated Ia molecules. The kinetics of antigen presentation to LTTC by P388AD were similar to the kinetics observed for splenic APC, although the magnitude of the proliferative response to LTTC to TGG was generally lower when antigen (Ag) was presented by the tumor cells compared to splenic antigen-presenting cells (APC). However, the magnitude of T-cell proliferation of immune lymph node (LN) T cells was comparable when Ag was presented on tumor cells or splenic APC. Several experiments suggested that Ag uptake and/or processing may be less effective in P388AD tumor cells as compared to normal splenic APC. A nonadherent Ia+, IL-1- tumor cell line (P388NA), which was isolated from the same parental tumor as P388AD, was also tested for the ability to present Ag to primed T lymphocytes and Ag-reactive LTTC. In contrast, to P388AD, the nonadherent tumor cell failed to present TGG under identical culture conditions even though Ia molecules were expressed on the tumor cells and Ag uptake had occurred. However, the defect in Ag presentation by P388NA could be corrected if an exogenous source of purified interleukin 1 was supplied to the cultures. A unique opportunity thus exists with both the P388AD and P388NA tumor cell lines to decipher some of the molecular interactions leading to T-cell proliferation during antigen presentation.

Shoulder joint-related motor cortex cells show continuously graded changes in activity, centered on a preferred movement direction, during active arm movements in 8 directions away from a central starting position (Georgopoulos et al., 1982). We demonstrate here that many of these cells show similar large continuously graded changes in discharge when the monkey compensates for inertial loads which pull the arm in 8 different directions. These load-dependent discharge variations are typically unimodal, centered on one load direction called the cell's load axis, and are often sufficiently continuous, symmetric, and broad as to show a good fit to a sinusoidal curve. A vectorial representation of cell activity indicates that the pattern of load-dependent activity changes in the population forms a signal whose direction is appropriate to compensate for the loads. The responses of single cells to different combinations of movement and load direction are often complex. Nevertheless, the mean activity of the sample population under any condition of movement direction and load direction can be described reasonably well by a simple linear summation of the movement-related discharge without any loads, and the change in tonic activity of the population caused by the load, measured prior to movement. The strength of the load-dependent discharge variation differs among cells. Cells can be sorted into 2 phasic and 2 tonic groups that show differing degrees of sensitivity to loads. In particular, it was found that the greater the degree of cell discharge variation associated with different actively maintained limb postures, the greater the activity changes caused by loads. No similar correlation was found for the degree of discharge variation during movement. Preliminary evidence suggests that phasic and tonic cell groups may be spatially segregated in the motor cortex. These observations are consistent with the idea that there exists in the motor cortex activity encoding aspects of movement kinematics, as well as movement dynamics. These observations are in agreement with studies of more distal arm joints, showing that the activity of certain motor cortex cells varies with the patterns of muscle activity and output forces required to produce a movement. These experiments extend the description of the control of the direction of movement of a multiple degree-of-freedom joint into the spatial (direction) domain to a greater extent than previously achieved.

Several different forms of hGH have been isolated from the pituitary, but little is known about modifications of synthesized forms that may exist in the circulation. We used a combination of serum immunoextraction with gel electrophoresis and electrophoretic blotting to detect circulating hGH isohormones. Three different components were identified, with the predominant form being 22,000 MW isomer. The method is sensitive to nanogram quantities of hGH and is applicable to the screening of human serum for the presence of variants of hGH.

Odontogenic sinus tracts are the most common cause of a chronically draining, fixed, nodulocystic papule of the face and neck. Injury or disease of a tooth may result in a periapical abscess that subsequently dissects along the path of least resistance and erupts through the skin. If recognized early, the sinus tract usually resolves after appropriate endodontic therapy or extraction.

We have previously demonstrated that peritoneal macrophages (M phi S) from C3H mice were resistant to in vitro infection by ectromelia virus, following activation by intraperitoneal injection of the immunomodulator Corynebacterium parvum. In contrast, resident and mineral oil-elicited M phi S were fully susceptible to virus infection. This report analyzes the infectious cycle of ectromelia virus in C parvum-activated and mineral oil-elicited M phi S and demonstrates that an abortive infection occurred in the activated M phi S that blocked the infectious cycle prior to the release of DNA from the infecting virions. The kinetics of adsorption of radiolabeled virus were similar in both susceptible and resistant M phi cultures; however, viral-induced incorporation of uridine and thymidine occurred only in the mineral oil-elicited and not the C parvum-activated M phi S. In addition, the late protein hemagglutinin was only detected in infected cultures of susceptible mineral oil-elicited M phi S. An electron micrographic analysis of the infectious cycle indicated that the adsorption of virus to the plasma membrane, uptake into lysosomes, and the primary undercoating and release of viral cores into the M phi cytoplasm were identical in both M phi types. In contrast, secondary uncoating (release of genomic DNA from the viral cores into the cytoplasm) was never detected in infected C parvum M phi S. These data are consistent with our previous findings and with the hypothesis that activation of M phi S by C parvum induces an interferon-mediated resistance to ectromelia virus infection.

An antibody response against a thymic-dependent Ag requires cognate recognition of the Ag by B and T cells. Functional T-B cell (T-B) interaction involves binding of Ag by B cell surface Ig, internalization and processing of Ag, expression of an Ag fragment in the context of Ia, binding of Ag/Ia by the TCR and binding of T cell-derived lymphokines by B cell lymphokine receptors. It is becoming increasingly evident that B and T cell accessory molecules also are involved in T-B interactions. To determine the role of accessory molecules in T-B collaboration, we have designed a system in which T-B interaction was artificially induced in the absence of carrier protein. TNP-modified, turkey gamma-globulin-specific, Th cells were allowed to form conjugates with TNP-specific B cells in the absence of hapten-carrier complex. Both B and T cells were induced to proliferate and B cells partially differentiated into antibody-secreting cells when B cells were cultured with TNP-modified but not unmodified T cells. The activation of B cells by TNP-modified T cells was not MHC restricted but was blocked by anti-Ia antibodies, suggesting a role for Ia distinct from Ag presentation. Furthermore, B cell proliferation was also inhibited by antibodies to L3T4 and LFA-1, suggesting a functional accessory role for these molecules in induction of B cell proliferation/differentiation.

Interleukin-1 (IL-1) mediates components of the acute-phase response, stimulates granulocyte metabolism, and induces endothelial cell surface changes. We studied the effects of human recombinant IL-1 beta (rIL-1 beta) or rIL-1 alpha on circulating granulocytes, their sequestration within the pulmonary microvasculature, pulmonary edema formation, and changes in pulmonary vascular permeability to 125I-labeled albumin. rIL-1 beta administration induced significant (P less than 0.03) but transient granulocytopenia followed by significant (P less than 0.04) neutrophilia and significant (P less than 0.04) pulmonary leukostasis compared with saline-infused rabbits. Rabbits preinfused with 125I-labeled rabbit serum albumin and administered saline, rIL-1 beta, or rIL-1 alpha were sacrificed, and lung wet/dry weight ratios and bronchoalveolar lavage fluid and plasma 125I activities determined. Both rIL-1 beta and rIL-1 alpha increased lung wet/dry weight ratios (P less than 0.025 and P less than 0.01, respectively) compared with saline controls. rIL-1 beta increased bronchoalveolar lavage fluid/plasma 125I radioactivity ratios (P less than 0.025). Electron microscopic analysis of lung sections obtained from rIL-1 beta-infused animals demonstrated endothelial injury, perivascular edema, and extravasation of an ultrastructural permeability tracer. The observation that human rIL-1 can evoke acute pulmonary vascular endothelial injury and lung edema in rabbits supports the hypothesis that IL-1 may play a role in the pathogenesis of the adult respiratory distress syndrome.

A single subcutaneous injection of monocrotaline in rats provokes lung injury, inflammation, and progressive pulmonary hypertension. The specific mediators of the lung injury and inflammation and the relation of these events to the ensuing hypertensive pulmonary vascular disease are not understood. Since the monokine interleukin 1 (IL-1) has been implicated in acute inflammatory reactions, the present study tested the hypotheses that monocrotaline promotes the appearance of IL-1 in the bronchoalveolar spaces of treated rats and that accumulation of the monokine coincides temporally with development of lung injury, inflammation, and/or pulmonary hypertension. As expected, monocrotaline administration was associated with an early phase of pulmonary edema, manifest at Day 7 post-treatment as an increase in the lung wet-to-dry weight ratio, followed at Day 14 post-treatment by development of pulmonary hypertension as evidenced by progressive right ventricular hypertrophy. Lung inflammation also was present at Days 14 and 21 after monocrotaline as indicated by the accumulation of leukocytes in the bronchoalveolar lavage fluid and by an increase in the lung tissue activity of the granulocyte-specific enzyme myeloperoxidase. Interleukin 1, bioassayed in bronchoalveolar lavage fluid using the standard D10 T-cell assay system, was increased slightly at Day 4 postmonocrotaline, returned to baseline at Day 7, and was markedly elevated at Days 14 and 21 after monocrotaline treatment. These observations indicate that increases in the bronchoalveolar lavage fluid content of IL-1 bioactivity are temporally related to the evolution of monocrotaline-induced lung injury, inflammation, and pulmonary hypertension and suggest that the monokine may play a pathogenetic role in these events.

Human polymorphonuclear leukocytes (PMN) were purified from purified protein derivative (PPD)-immune individuals and assayed for their ability to act as antigen-presenting cells for PPD to autologous purified lymphocytes or as accessory cells in a PHA mitogenic response with autologous lymphocytes. PMNs were very efficient accessory cells in that the PHA mitogenic response was augmented fourfold by the addition of PMNs to the culture. In contrast, PMNs did not appear to present antigen. Accessory cell function by PMNs was HLA unrestricted in that allogeneic PMNs were equally effective accessory cells. Furthermore, the accessory cell function of PMNs appeared to require cell-cell contact, since culture supernatants from PMNs failed to replace intact PMNs in the mitogenic response.