Productive infection of neonatal CD8+ T lymphocytes by HIV-1

CD8+ T lymphocytes confer significant but ultimately insufficient protection against HIV infection. Here we report that activated neonatal CD8+ T cells can be productively infected in vitro by macrophage-tropic (M-tropic) HIV-1 isolates, which are responsible for disease transmission, whereas they are resistant to T cell-tropic (T-tropic) HIV strains. Physiological activation of CD8-alpha/beta+ CD4- T cell receptor-alpha/beta+ neonatal T cells, including activation by allogeneic dendritic cells, induces the accumulation of CD4 messenger RNA and the expression of CD4 Ag on the cell surface. The large majority of anti-CD3/B7.1-activated cord blood CD8+ T cells coexpress CD4, the primary HIV receptor, as well as CCR5 and CXCR4, the coreceptors used by M- and T-tropic HIV-1 strains, respectively, to enter target cells. These findings are relevant to the rapid progression of neonatal HIV infection. Infection of primary HIV-specific CD8+ T cells may compromise their survival and thus significantly contribute to the failure of the immune system to control the infection. Furthermore, these results indicate a previously unsuspected level of plasticity in the neonatal immune system in the regulation of CD4 expression by costimulation.

Sex differences in the perception of noxious experimental stimuli: a meta-analysis

Fillingim and Maixner (Fillingim, R.B. and Maixner, W., Pain Forum, 4(4) (1995) 209-221) recently reviewed the body of literature examining possible sex differences in responses to experimentally induced noxious stimulation. Using a 'box score' methodology, they concluded the literature supports sex differences in response to noxious stimuli, with females displaying greater sensitivity. However, Berkley (Berkley, K.J., Pain Forum, 4(4) (1995) 225-227) suggested the failure of a number of studies to reach statistical significance suggests the effect may be small and of little practical significance. This study used meta-analytic methodology to provide quantitative evidence to address the question of the magnitude of these sex differences in response to experimentally induced pain. We found the effect size to range from large to moderate, depending on whether threshold or tolerance were measured and which method of stimulus administration was used. The values for pressure pain and electrical stimulation, for both threshold and tolerance measures, were the largest. For studies employing a threshold measure, the effect for thermal pain was smaller and more variable. The failures to reject the null hypothesis in a number of these studies appear to have been a function of lack of power from an insufficient number of subjects. Given the estimated effect size of 0.55 threshold or 0.57 for tolerance, 41 subjects per group are necessary to provide adequate power (0.70) to test for this difference. Of the 34 studies reviewed by Fillingim and Maixner, only seven were conducted with groups of this magnitude. The results of this study compels to caution authors to obtain adequate sample sizes and hope that this meta-analytic review can aid in the determination of sample size for future studies.

CTLA-4 ligation delivers a unique signal to resting human CD4 T cells that inhibits interleukin-2 secretion but allows Bcl-X(L) induction

We have assessed the functional effects of a panel of CTLA-4 mAbs on resting human CD4+ T cells. Our results demonstrate that some CTLA-4 mAbs can inhibit proliferative responses of resting CD4+ cells and cell cycle transition from G0 to G1. The inhibitory effects of CTLA-4 were evident within 4 h, at a time when cell surface CTLA-4 expression remained undetectable. Other CTLA-4 mAbs had no detectable inhibitory effects, indicating that binding of Ab to CTLA-4 alone is not sufficient to mediate down-regulation of T cell responses. Interestingly, while IL-2 production was shut off, inhibitory anti-CTLA-4 mAbs permitted induction and expression of the cell survival gene bcl-X(L). Consistent with this observation, cells remained viable and apoptosis was not detected after CTLA-4 ligation.

Intrinsic resistance to T cell infection with HIV type 1 induced by CD28 costimulation

When HIV-infected leukocytes are activated by the CD28 costimulatory receptor, HIV-1 is rapidly cleared from cultures, suggesting that costimulation can render T cells resistant to HIV-1 infection. In this study we tested the hypothesis that enhanced secretion of cytokines or chemokines could account for CD28-induced antiviral effects. In an acute infection system, resistance to infection with macrophage-tropic strains of HIV-1 was shown to be comprised of both soluble and cell-associated components. Induction of HIV-1 resistance was specific for CD28 costimulation, in that a variety of other accessory receptors, such as CD2, CD4, CD5, and MHC class I, failed to confer the antiviral resistance. The soluble component was secreted by both CD4 and CD8 T cells, was not unique to CD28 costimulation, and could be neutralized by removal of C-C chemokines (RANTES (regulated upon activation, normal T cell expressed and secreted) and macrophage inflammatory protein-1alpha and -1beta) from the culture supernatants of costimulated CD4 T cells. In contrast, CD28 stimulation of CD4 cells resulted in the specific induction of a pronounced intrinsic resistance to HIV-1 infection by macrophage tropic isolates of HIV-1.

CSQ: five factors or fiction?

OBJECTIVE

The Coping Strategies Questionnaire (CSQ), a rationally constructed pain coping assessment instrument, was conceived to measure the extent to which patients used six different cognitive coping strategies and two behavioral coping strategies. A number of studies have factor analyzed the original scales but have not found a reliable factor structure. Recent studies by Turtle et al. and Swartzman et al. have obtained a five-factor solution performing exploratory factor analysis on the individual items. Robinson and associates from the University of Florida performed an item level exploratory factor analysis on a much larger sample (n = 965) and found a six-factor solution that was relatively supportive of the original rationally derived scales. The purpose of the present investigation was to perform a confirmatory factor analysis using the LISREL structural equation modeling program to compare these three different factor structures.

PATIENTS

A sample of 472 chronic patients was used.

RESULTS AND CONCLUSIONS

The results indicated that the Florida six-factor model was a better fit to the sample data than either of the five-factor models. Creation of the Coping Strategy Questionnaire Revised (CSQ-R), which retains 27 of the original items, is suggested.

Intrinsic resistance to T cell infection with HIV type 1 induced by CD28 costimulation

When HIV-infected leukocytes are activated by the CD28 costimulatory receptor, HIV-1 is rapidly cleared from cultures, suggesting that costimulation can render T cells resistant to HIV-1 infection. In this study we tested the hypothesis that enhanced secretion of cytokines or chemokines could account for CD28-induced antiviral effects. In an acute infection system, resistance to infection with macrophage-tropic strains of HIV-1 was shown to be comprised of both soluble and cell-associated components. Induction of HIV-1 resistance was specific for CD28 costimulation, in that a variety of other accessory receptors, such as CD2, CD4, CD5, and MHC class I, failed to confer the antiviral resistance. The soluble component was secreted by both CD4 and CD8 T cells, was not unique to CD28 costimulation, and could be neutralized by removal of C-C chemokines (RANTES (regulated upon activation, normal T cell expressed and secreted) and macrophage inflammatory protein-1alpha and -1beta) from the culture supernatants of costimulated CD4 T cells. In contrast, CD28 stimulation of CD4 cells resulted in the specific induction of a pronounced intrinsic resistance to HIV-1 infection by macrophage tropic isolates of HIV-1.

Differential regulation of HIV-1 fusion cofactor expression by CD28 costimulation of CD4+ T cells

Activation of CD4(+) T lymphocytes from human immunodeficiency virus-type 1 (HIV-1)-infected donors with immobilized antibodies to CD3 and CD28 induces a virus-resistant state. This effect is specific for macrophage-tropic HIV-1. Transcripts encoding CXCR4/Fusin, the fusion cofactor used by T cell line-tropic isolates, were abundant in CD3/CD28-stimulated cells, but transcripts encoding CCR5, the fusion cofactor used by macrophage-tropic viruses, were not detectable. Thus, CD3/CD28 costimulation induces an HIV-1-resistant phenotype similar to that seen in some highly exposed and HIV-uninfected individuals.

The Coping Strategies Questionnaire: a large sample, item level factor analysis

OBJECTIVE

The Coping Strategies Questionnaire (CSQ), a measure of coping in chronic pain patients, was subjected to item-level exploratory factor analysis.

SUBJECTS

A sample of 965 chronic pain patients were used in the analysis.

RESULTS

Principal components analysis using a varimax rotation procedure identified nine factors that accounted for 54.5% of the variance. Of these nine factors, the first five represent subscales of the original CSQ subscales. The catastrophizing subscale replicated with significant loadings for all six original items, and ignoring sensations replicated with five of six items. Factors representing reinterpreting pain sensations, coping self-statements, and diverting attention subscales also appeared. The items from the praying and hoping subscale split into separate praying and hoping factors (factors 6 and 8). When reliability coefficients were calculated, factors 7 through 9 had unacceptably low internal consistency and thus were not considered stable factors. Correlations between factors 1 through 6 and other measures of psychological and physical functioning were calculated in the construct validation portion of this study. Previously found relationships were replicated in that the correlations between CSQ factor scores and measures of pain, depression, and disability were in the same direction in this data set as those previously reported.

Bias effects in three common self-report pain assessment measures

OBJECTIVE

Past research has shown response biases to influence the accuracy of results from self-report measures. In pain assessment, where a percentage of patients have financial and other reasons to minimize or exaggerate psychological disturbance, it becomes especially important to identify the influence of response bias in self-report of adjustment. This study investigated the susceptibility of three commonly used self-report pain assessment measures to response bias.

DESIGN

This study used a within-subjects (asymptomatic subjects) design with two experimental conditions and nonequivalent control group (chronic pain patients).

SUBJECTS

Experimental group: 40 students enrolled in an occupational therapy program at a major southeastern United States university.

CONTROL GROUP

200 subjects referred to a multidisciplinary pain clinic at a major teaching hospital.

MEASURES

Coping Strategies Questionnaire, Multidimensional Pain Inventory, and Pain Beliefs and Perceptions Inventory.

RESULTS

With few exceptions, asymptomatic subjects scored significantly differently on these measures while portraying themselves as either coping well or coping poorly. In addition, when using the "coping poorly" response set, asymptomatic subjects reproduced scores similar to those of symptomatic chronic pain patients.

CONCLUSION

The susceptibility to manipulation appeared constant across the three measures, a finding that highlighted the difficulties clinicians and researchers encounter in accurate interpretation of results from these measures in the absence of validity indicators. This study also emphasizes the ease with which subjects with sufficient motivation can present themselves in an untruthful and manipulative manner and can generate scores that are, on their own, difficult to distinguish from those of a group of typical chronic pain patients.

Spontaneous gas gangrene: an unusual complication of colonic carcinoma

Clostridium septicum myonecrosis is an acutely painful and rapidly fatal infection occurring in the absence of trauma. Urgent surgery is essential both to maximize survival and to provide effective pain control. The majority of patients who develop this infection have an underlying malignancy and clinicians involved in the care of cancer patients should be aware of this condition. We present a case report and summarize the literature to date.

Molecular genetic analysis of volatile-anesthetic action

The mechanism(s) and site(s) of action of volatile inhaled anesthetics are unknown in spite of the clinical use of these agents for more than 150 years. In the present study, the model eukaryote Saccharomyces cerevisiae was used to investigate the action of anesthetic agents because of its powerful molecular genetics. It was found that growth of yeast cells is inhibited by the five common volatile anesthetics tested (isoflurane, halothane, enflurane, sevoflurane, and methoxyflurane). Growth inhibition by the agents is relatively rapid and reversible. The potency of these compounds as yeast growth inhibitors directly correlates with their lipophilicity as is predicted by the Meyer-Overton relationship, which directly correlates anesthetic potency of agents and their lipophilicity. The effects of isoflurane on yeast cells were characterized in the most detail. Yeast cells survive at least 48 h in a concentration of isoflurane that inhibits colony formation. Mutants resistant to the growth-inhibitory effects of isoflurane are readily selected. The gene identified by one of these mutations, zzz4-1, has been cloned and characterized. The predicted ZZZ4 gene product has extensive homology to phospholipase A2-activating protein, a GO effector protein of mice. Both zzz4-1 and a deletion of ZZZ4 confer resistance to all five of the agents tested, suggesting that signal transduction may be involved in the response of these cells to volatile anesthetics.

Antiviral effect and ex vivo CD4+ T cell proliferation in HIV-positive patients as a result of CD28 costimulation

Because stimulation of CD4+ lymphocytes leads to activation of human immunodeficiency virus-type 1 (HIV-1) replication, viral spread, and cell death, adoptive CD4+ T cell therapy has not been possible. When antigen and CD28 receptors on cultured T cells were stimulated by monoclonal antibodies (mAbs) to CD3 and CD28 that had been immobilized, there was an increase in the number of polyclonal CD4+ T cells from HIV-infected donors. Activated cells predominantly secreted cytokines associated with T helper cell type 1 function. The HIV-1 viral load declined in the absence of antiretroviral agents. Moreover, CD28 stimulation of CD4+ T cells from uninfected donors rendered these cells highly resistant to HIV-1 infection. Immobilization of CD28 mAb was crucial to the development of HIV resistance, as cells stimulated with soluble CD28 mAb were highly susceptible to HIV infection. The CD28-mediated antiviral effect occurred early in the viral life cycle, before HIV-1 DNA integration. These data may facilitate immune reconstitution and gene therapy approaches in persons with HIV infection.

Pain severity, negative affect, and microstressers as predictors of life interference in TMD patients

The purpose of this study was to examine the relationships among negative affect (depression, anxiety, and anger), microstressors (hassles), temporomandibular disorder (TMD) pain severity, and life interference, using structural equations modeling. One hundred four subjects were recruited from the Parker Mahan Facial Pain Clinic at the University of Florida. Significant positive direct effects were found for paths between pain severity and life interference; pain severity and negative affect; and negative affect and life interference. These results are consistent with a learning or behavioral model of suffering and suggest that negative affect is an important mediating variable in the relationship between pain and life interference. Microstressors were not a significant predictor and may not be a relevant issue in the TMD population. The results suggest that the impact of chronic pain conditions is influenced by both pain and negative affect, and assessment and treatment of chronic TMD disorders may better benefit from a multidisciplinary approach.

Comparison of the alteration of cardiac function by sevoflurane, isoflurane, and halothane in the isolated working rat heart

OBJECTIVES

Despite its widespread use, little is known about sevoflurane's physiologic effects. The direct myocardial effects of sevoflurane were compared with both halothane and isoflurane.

DESIGN

Administration of minimum alveolar concentration (MAC) fractions of anesthetic (0 to 3.0) was systematically varied to decrease the possibility of time-related effects on measured parameters.

SETTING

Isolated rat hearts were perfused using a working heart model where the parameters affecting myocardial work were carefully controlled and monitored.

PARTICIPANTS

To avoid confounding effects of prior anesthetic administration, hearts were removed from rats, after decapitation, in the absence of anesthetic.

INTERVENTIONS

In the first series, isolated perfused rat hearts were exposed to one of the three anesthetics in doses of 0 to 1.5 times MAC. In the second series, hearts were exposed to either sevoflurane or isoflurane in doses of 0 to 3.0 times MAC. The following variables were measured: the rate of change of left ventricular pressure; aortic flow rate; cardiac output; left ventricular end-diastolic pressure; the time constant of isovolumetric relaxation; and coronary vascular resistance. Oxygen consumption was measured during the first series.

MEASUREMENTS AND MAIN RESULTS

In the first series, all systolic variables were reduced in the presence of halothane when compared with either isoflurane or sevoflurane. Halothane affected diastolic function to a greater degree than either sevoflurane or isoflurane, as measured by the rate of relaxation and end-diastolic pressure. In the second series, at a dose of 3.0 times MAC, both sevoflurane and isoflurane decreased systolic and diastolic function, with a greater reduction in cardiac output, and peak aortic flow and higher left ventricular end-diastolic pressures observed with isoflurane. Coronary resistance and oxygen consumption were not affected by any of the anesthetics.

CONCLUSIONS

These data suggest that sevoflurane depresses cardiac function less than either halothane in doses of 1.0 and 1.5 x MAC or isoflurane at doses of 3 x MAC.

Interferon (IFN) beta acts downstream of IFN-gamma-induced class II transactivator messenger RNA accumulation to block major histocompatibility complex class II gene expression and requires the 48-kD DNA-binding protein, ISGF3-gamma

Interferon (IFN) gamma, a cardinal proinflammatory cytokine, induces expression of the gene products of the class II locus of the major histocompatibility complex (MHC), whereas IFN-alpha or -beta suppresses MHC class II expression. The mechanism of IFN-beta-mediated MHC class II inhibition has been unclear. Recently, a novel factor termed class II transactivator (CIITA) has been identified as essential for IFN-gamma-induced MHC class II transcription. We studied the status of IFN-gamma-induced CIITA messenger RNA (mRNA) accumulation and CIITA-driven transactivation in IFN-beta-treated cells and used cell lines that had defined defects in the type I IFN response pathway to address the roles of IFN signaling components in the inhibition of MHC class II induction. IFN-beta treatment did not suppress IFN-gamma-induced accumulation of CIITA mRNA. After cells were stably transfected with CIITA, endogenous MHC class II genes were constitutively expressed, and MHC class II promoters, delivered by transfection, were actively transcribed in CIITA-expressing cells. Expression of these promoters was significantly impaired by pretreatment with IFN-beta. These results suggest that IFN-beta acts downstream of CIITA mRNA accumulation, and acts in part by reducing the functional competence of CIITA for transactivating MHC class II promoters. IFN stimulated gene factor 3 (ISGF3) gamma was essential for IFN-beta to mediate inhibition of MHC class II induction, regardless of whether MHC class II transcription was stimulated by IFN-gamma or directly by CIITA expression. Results of these experiments suggest that inhibition of MHC class II in IFN-beta-treated cells requires expression of gene(s) directed by the ISGF3-IFN-stimulated response element pathway, and that these gene product(s) may act by blocking CIITA-driven transcription of MHC class II promoters.

Relationship between MMPI-2 cluster profiles and surgical outcome in low-back pain patients

The purpose of this study was to investigate back surgery outcome differences based on Minnesota Multiphasic Personality Inventory-2 (MMPI-2) profile types. Four homogenous subgroups were found from a hierarchical cluster analysis of 201 MMPI-2 profiles. These four clusters consisted of a Depressed-pathological profile, a conversion V profile (V-type), a neurotic Triad profile, and a within normal limit (WNL) profile. Patients in the WNL and Triad subgroups reported significantly more satisfaction with postsurgical improvement than did patients in the Depressed-pathological or V-type subgroups. The Triad subgroup also gave a more favorable subjective rating of surgical outcome than did patients in the Depressed-pathological or V-type subgroups. These groups also differed on measures of work status and nonwork-related physical activity levels but not on indices of pain.

Activation of class II MHC genes requires both the X box region and the class II transactivator (CIITA)

CIITA, a gene that can complement a transcriptional mutation of the major histocompatibility complex (MHC) class II genes, was tested for its ability to function as a coactivator, CIITA cDNA clones isolated showed alternative RNA splicing, but only one splice site combination was able to restore class II MHC gene expression. DNA-mediated transfection experiments showed that CIITA directs its activity through the X box element; the presence of CIITA leads to the formation of a higher order complex at the X box region; and CIITA contains a potent activation domain. These findings support the hypothesis that CIITA directly interacts with the MHC class II-specific transcription factors and is required for expression.

Molecular analysis of G1B and G3A IFN gamma mutants reveals that defects in CIITA or RFX result in defective class II MHC and Ii gene induction

Class II major histocompatibility complex (MHC) genes and the invariant (Ii) gene are inducible by interferon-gamma (IFN gamma) but not by interferon-alpha and interferon-beta. The promoter regions of these genes contain three regulatory elements that mediate constitutive and IFN gamma-induced expressions; however, none of the DNA-binding proteins that interact with these elements are regulated by IFN gamma. Recently, a gene coding for a transactivator (CIITA) of class II MHC genes that complements a HLA-DR-negative immunodeficiency has been isolated. Using one IFN gamma mutant cell line (G3A) that is selectively defective in HLA-DR and Ii induction, four lines of evidence are presented to show that CIITA mediates the IFN gamma induction of HLA-DR and Ii genes. Analysis of another mutant line, G1B, indicates that the lack of DRA and Ii gene induction by IFN gamma is correlated with the lack of RFX DNA binding activity, thus providing the link between RFX and an IFN gamma response.

Variability of isometric and isotonic leg exercise: Utility for detection of submaximal effort

A number of studies have investigated the use of variability measures in the detection of submaximal or insincere efforts in strength testing. The underlying assumption of these approaches is that submaximal efforts will be more variable than maximal efforts. Previous studies have investigated the variability of torque production in isometric or isokinetic tasks with mixed results. The present study investigated the variability of torque production and velocity in isometric and isotonic leg extension tasks, respectively. Fifteen asymptomatic subjects participated in a within-subject counterbalanced design in which they were asked to perform maximally and submaximally in both isometric and isotonic leg extension tasks. Results indicated that both isometric and isotonic tasks showed greater variability (measured by coefficient of variation) in the submaximal effort condition. However, the sensitivity to detect submaximal efforts was much greater for the isotonic velocity variability condition. It was concluded that the isotonic approach showed promise for clinical application, but that the isometric task had unacceptably poor classification rates, consistent with previous research.

Class II MHC transcriptional mutants are defective in higher order complex formation

Human class II MHC genes are regulated in part by a series of conserved upstream sequence elements termed the X1, X2, and Y boxes. Class II MHC transcriptional mutant B cell lines have been defined that differ with regard to the presence of RFX, an X1 box DNA-binding activity. To further characterize these mutant cell lines, we tested the ability of these conserved upstream elements to respond to the presence of known transcriptional activation domains. A series of HLA-DRA promoter reporter constructions carrying Gal4 binding sites and GAL4 fusion protein expression vectors were cotransfected into both wild type B cells and mutant B cells representing the two RFX phenotypes. Regardless of RFX or class II phenotype, the activation domains of GAL4-VP16 and GAL4-E1a could synergistically stimulate expression of constructions containing both the X2 and Y boxes. GAL4-VP16- and GAL4-E1a-mediated expression was inhibited by the presence of the X1 box in cells that contained RFX. In mutant cells that lacked RFX, GAL4-VP16 activation was not inhibited. In the RFX-positive class II mutant cell line RJ2.2.5, the X1 box inhibitory activity could be overcome by separating the Gal4 site from the X1 box by two additional helical turns, suggesting that the RFX factor is bound at the X1 site and sterically interferes with activation. This was not the case in wild type B cells, suggesting that a stable higher order complex forms in wild type cells and not in the mutant cells.

Class II MHC transcriptional mutants are defective in higher order complex formation

Human class II MHC genes are regulated in part by a series of conserved upstream sequence elements termed the X1, X2, and Y boxes. Class II MHC transcriptional mutant B cell lines have been defined that differ with regard to the presence of RFX, an X1 box DNA-binding activity. To further characterize these mutant cell lines, we tested the ability of these conserved upstream elements to respond to the presence of known transcriptional activation domains. A series of HLA-DRA promoter reporter constructions carrying Gal4 binding sites and GAL4 fusion protein expression vectors were cotransfected into both wild type B cells and mutant B cells representing the two RFX phenotypes. Regardless of RFX or class II phenotype, the activation domains of GAL4-VP16 and GAL4-E1a could synergistically stimulate expression of constructions containing both the X2 and Y boxes. GAL4-VP16- and GAL4-E1a-mediated expression was inhibited by the presence of the X1 box in cells that contained RFX. In mutant cells that lacked RFX, GAL4-VP16 activation was not inhibited. In the RFX-positive class II mutant cell line RJ2.2.5, the X1 box inhibitory activity could be overcome by separating the Gal4 site from the X1 box by two additional helical turns, suggesting that the RFX factor is bound at the X1 site and sterically interferes with activation. This was not the case in wild type B cells, suggesting that a stable higher order complex forms in wild type cells and not in the mutant cells.

Multivariate cluster analysis of the MMPI-2 in chronic low-back pain patients

OBJECTIVE

The purpose of our study was to investigate whether Minnesota Multiphasic Personality Inventory-2 cluster solutions of chronic low-back pain patients would replicate those found in previous research with the Minnesota Multiphasic Personality Inventory.

SETTING

A multidisciplinary pain clinic in the southeastern United States.

PATIENTS

The subjects were 201 chronic low-back pain patients who had suffered a work-related back injury.

OUTCOME MEASURES

The Minnesota Multiphasic Personality Inventory-2.

RESULTS

We found four relatively homogeneous subgroups of chronic low-back pain patients that were similar to those identified by previous researchers using data collected with the Minnesota Multiphasic Personality Inventory.

CONCLUSION

These findings indicate that interpretations of the Minnesota Multiphasic Personality Inventory-2 should parallel those of the Minnesota Multiphasic Personality Inventory for chronic low-back pain patients. They further suggest that the results of Minnesota Multiphasic Personality Inventory-based studies are also applicable to Minnesota Multiphasic Personality Inventory-2.

Influence of education on self-perceived attitudes about HIV/AIDS among human services providers

Participants in a number of different HIV/AIDS educational programs, varying in content, length of course, and student audience, were surveyed to determine if education could help reduce fear and increase comfort in work with HIV/AIDS clients. It was hypothesized that attitude scores would improve following exposure to the educational programs. A retrospective pretest-posttest survey design consisting of Likert statements was used. A t test for paired samples determined if attitude scores improved following exposure to the educational programs. An analysis of variance determined if significant differences in pretest and posttest scores existed among the groups. Within groups, there was a positive increase in self-assessed attitude scores. Multiple group comparisons indicated significant differences between groups that appear to be related to program content and length. Workplace risk and whether a program was elective may have also been factors affecting attitude.

Protease treatment of nuclear extracts distinguishes between class II MHC X1 box DNA-binding proteins in wild-type and class II-deficient B cells

The X box region is critical for directing the expression of class II major histocompatibility complex genes in B lymphocytes. Although several class II promoter-specific DNA binding factors have been described, only the X box region factor, RFX, shows a genetic correlation with class II expression, being deficient in some B cell lines derived from patients with class II-deficient congenital immunodeficiency. To further evaluate the role of X box DNA-binding proteins in class II gene expression, the role of the X box region was examined in both class II-positive and -negative lymphoid cells. In addition to the wild-type B cell line Raji, two class II transcriptional mutant cell lines, SJO and RJ2.2.5, and Jurkat, a class II negative T cell line, were examined. In contrast to wild-type B cells, neither of the class II mutant cell lines could use the X box region to direct the expression of a transiently transfected reporter gene, indicating that the X box-dependent transcriptional pathway is defective in these cells. The binding activity of the X1 box DNA-binding protein RFX was examined and found to be present in wild-type B cells and the mutant RJ2.2.5 but was absent in SJO and Jurkat. However, other X1 box-specific activities were detected in all these cell lines. To determine whether these different X1 box activities represented distinct DNA binding proteins or multimeric forms of the same factor(s), protease treatment of the crude nuclear extracts followed by DNA-binding assays were carried out and demonstrated that B cell extracts contain at least two X1-specific factors. One of these cleaved products (band 1 pk) correlates with RFX activity. A similar comparison with protease-treated extracts prepared from Jurkat cells demonstrated the presence of the band 1pk activity despite an absence of the native RFX activity. In contrast, protease treatment and analysis of SJO extracts showed no detectable levels of the band 1pk activity. These results demonstrate that multiple X1 box-specific DNA-binding activities exist in all lymphoid cells, but the presence of an actively binding RFX species correlates with class II transcription.