High MDR-1 expression by MAIT cells confers resistance to cytotoxic but not immunosuppressive MDR-1 substrates

High expression of the ATP-binding cassette-multi-drug efflux protein 1 (MDR1) is a striking feature of mucosal-associated invariant T (MAIT) cells, a prominent human innate-like T cell subset. We demonstrate significantly higher MDR1 expression by CD8 ⁺ CD161 ⁺⁺ Vα7.2 ⁺ MAIT cells than the phenotypically and functionally related CD8 ⁺ CD161 ⁺⁺ Vα7.2-subset and show MDR1 expression to be similarly high throughout MAIT CD4 ⁺ , CD8 ⁺ , double-negative (DN) and double-positive (DP) cell subsets. We demonstrate the MAIT cell-predominant CD8⁺ CD161⁺⁺ subset to uniquely and efficiently efflux the cytotoxic anthracycline daunorubicin, retain function on daunorubicin exposure and demonstrate MDR1-dependent protection from daunorubicin-induced apoptosis. By contrast, CD8⁺ CD161⁺⁺ Vα7.2⁺ MAIT cells were not protected from the anti-proliferative and cytotoxic effects of the immunosuppressive MDR1 substrates tacrolimus and mycophenoic acid, although function following MAIT cell-specific T cell receptor (TCR)-dependent and -independent stimulation was preserved on in-vitro exposure to these agents. Overall, our data further define MDR1 expression by CD161⁺⁺ T and MAIT cells and demonstrate the potential for high MDR1 expression by MAIT cells to confer resistance to cytotoxic MDR1 substrates in vivo . As our understanding of the importance of MAIT cells in human immunity and immunopathology grows, this is an important observation for clinical contexts such as the treatment of malignancy, autoimmunity and post-transplant immunosuppression.

Shared and Distinct Phenotypes and Functions of Human CD161++ Vα7.2+ T Cell Subsets

Human mucosal-associated invariant T (MAIT) cells are an important T cell subset that are enriched in tissues and possess potent effector functions. Typically such cells are marked by their expression of Vα7.2-Jα33/Jα20/Jα12 T cell receptors, and functionally they are major histocompatibility complex class I-related protein 1 (MR1)-restricted, responding to bacterially derived riboflavin synthesis intermediates. MAIT cells are contained within the CD161++ Vα7.2+ T cell population, the majority of which express the CD8 receptor (CD8+), while a smaller fraction expresses neither CD8 or CD4 coreceptor (double negative; DN) and a further minority are CD4+. Whether these cells have distinct homing patterns, phenotype and functions have not been examined in detail. We used a combination of phenotypic staining and functional assays to address the similarities and differences between these CD161++ Vα7.2+ T cell subsets. We find that most features are shared between CD8+ and DN CD161++ Vα7.2+ T cells, with a small but detectable role evident for CD8 binding in tuning functional responsiveness. By contrast, the CD4+ CD161++ Vα7.2+ T cell population, although showing MR1-dependent responsiveness to bacterial stimuli, display reduced T helper 1 effector functions, including cytolytic machinery, while retaining the capacity to secrete interleukin-4 (IL-4) and IL-13. This was consistent with underlying changes in transcription factor (TF) expression. Although we found that only a proportion of CD4+ CD161++ Vα7.2+ T cells stained for the MR1-tetramer, explaining some of the heterogeneity of CD4+ CD161++ Vα7.2+ T cells, these differences in TF expression were shared with CD4+ CD161++ MR1-tetramer+ cells. These data reveal the functional diversity of human CD161++ Vα7.2+ T cells and indicate potentially distinct roles for the different subsets in vivo.

Early Molecular Stratification of High-risk Primary Biliary Cholangitis

High-risk primary biliary cholangitis (PBC), defined by inadequate response at one year to Ursodeoxycholic acid (UDCA), is associated with disease progression and liver transplantation. Stratifying high-risk patients early would facilitate improved approaches to care. Using long-term follow-up data to define risk at presentation, 6 high-risk PBC patients and 8 low-risk patients were identified from biopsy, transplant and biochemical archival records. Formalin-fixed paraffin-embedded (FFPE) liver biopsies taken at presentation were graded (Scheuer and Nakanuma scoring) and gene expression analysed using the NanoString® nCounter PanCancer Immunity 770-gene panel. Principle component analysis (PCA) demonstrated discrete gene expression clustering between controls and high- and low-risk PBC. High-risk PBC was characterised by up-regulation of genes linked to T-cell activation and apoptosis, INF-γ signalling and leukocyte migration and down-regulation of those linked to the complement pathway. CDKN1a, up-regulated in high-risk PBC, correlated with significantly increased expression of its gene product, the senescence marker p21^WAF1/Cip, by biliary epithelial cells. Our findings suggest high- and low-risk PBC are biologically different from disease outset and senescence an early feature in high-risk disease. Identification of a high-risk 'signal' early from standard FFPE tissue sections has clear clinical utility allowing for patient stratification and second-line therapeutic intervention.

Long-Term Fenofibrate Treatment in Primary Biliary Cholangitis Improves Biochemistry but Not the UK-PBC Risk Score

BACKGROUND

Fenofibrate (FF) has been suggested as a second-line agent in primary biliary cholangitis (PBC) patients who do not achieve adequate biochemical response to ursodeoxycholic acid (UDCA) monotherapy. Limited data exist on FF use beyond 12 months, and its long-term effects are unclear.

AIM

To study the biochemical outcome of long-term (>12 months) FF treatment in combination with UDCA (FF + UDCA) in PBC patients and to determine the effect on predicted prognosis using the UK-PBC Risk Score.

METHODS

This was a retrospective cohort study of all PBC patients treated in a specialist center with FF + UDCA therapy after failure to achieve biochemical response. Liver and renal biochemical indices and the UK-PBC Risk Score at baseline and at 12, 24, 36, 48, and 60 months of FF + UDCA treatment were compared. Biochemical response was assessed using the POISE trial criteria at the end of FF + UDCA treatment.

RESULTS

Data from 23 patients treated with FF + UDCA combination were analyzed. The median dose of fenofibrate was 200 mg/day, and median treatment duration was 21 months (range 1-123 months). Six (26 %) patients discontinued FF within 1 year. In patients who completed 12 months (n = 17) and long-term therapy, significant decrease in ALP was seen at 12 (p = 0.0002), 24 (p = 0.002), and 36 (p = 0.03) months. More than 75 % patients met the POISE criteria of ALP response at all study time points. There was no significant improvement in the 5-, 10-, and 15-year UK-PBC Risk Scores after FF + UDCA treatment. No significant renal impairment or adverse events were reported.

CONCLUSION

The long-term treatment of PBC patients with fenofibrate as an adjunct to UDCA is safe and effective in improving ALP, but the treatment did not significantly reduce the estimated probability of liver-related death or need for liver transplantation.

LLT1 and CD161 Expression in Human Germinal Centers Promotes B Cell Activation and CXCR4 Downregulation

Germinal centers (GCs) are microanatomical structures critical for the development of high-affinity Abs and B cell memory. They are organized into two zones, light and dark, with coordinated roles, controlled by local signaling. The innate lectin-like transcript 1 (LLT1) is known to be expressed on B cells, but its functional role in the GC reaction has not been explored. In this study, we report high expression of LLT1 on GC-associated B cells, early plasmablasts, and GC-derived lymphomas. LLT1 expression was readily induced via BCR, CD40, and CpG stimulation on B cells. Unexpectedly, we found high expression of the LLT1 ligand, CD161, on follicular dendritic cells. Triggering of LLT1 supported B cell activation, CD83 upregulation, and CXCR4 downregulation. Overall, these data suggest that LLT1–CD161 interactions play a novel and important role in B cell maturation within the GC in humans.

MAIT cells are licensed through granzyme exchange to kill bacterially sensitized targets

Mucosal-associated invariant T (MAIT) cells are an innate-like T-cell population restricted by the non-polymorphic, major histocompatibility complex class I-related protein 1, MR1. MAIT cells are activated by a broad range of bacteria through detection of riboflavin metabolites bound by MR1, but their direct cytolytic capacity upon recognition of cognate target cells remains unclear. We show that resting human MAIT cells are uniquely characterized by a lack of granzyme (Gr) B and low perforin expression, key granule proteins required for efficient cytotoxic activity, but high levels of expression of GrA and GrK. Bacterial activation of MAIT cells rapidly induced GrB and perforin, licensing these cells to kill their cognate target cells. Using a novel flow cytometry-based killing assay, we show that licensed MAIT cells, but not ex vivo MAIT cells from the same donors, can efficiently kill Escherichia coli-exposed B-cell lines in an MR1- and degranulation-dependent manner. Finally, we show that MAIT cells are highly proliferative in response to antigenic and cytokine stimulation, maintaining high expression of GrB, perforin, and GrA, but reduced expression of GrK following antigenic proliferation. The tightly regulated cytolytic capacity of MAIT cells may have an important role in the control of intracellular bacterial infections, such as Mycobacterium tuberculosis.

CD8αα Expression Marks Terminally Differentiated Human CD8+ T Cells Expanded in Chronic Viral Infection

The T cell co-receptor CD8αβ enhances T cell sensitivity to antigen, however studies indicate CD8αα has the converse effect and acts as a co-repressor. Using a combination of Thymic Leukemia (TL) antigen tetramer, which directly binds CD8αα, anti-CD161, and anti-Vα7.2 antibodies we have been able for the first time to clearly define CD8αα expression on human CD8 T cells subsets. In healthy controls CD8αα is most highly expressed by CD161 “bright” (CD161++) mucosal associated invariant T (MAIT) cells, with CD8αα expression highly restricted to the TCR Vα7.2+ cells of this subset. We also identified CD8αα-expressing populations within the CD161 “mid” (CD161+) and “negative” (CD161−) non-MAIT CD8 T cell subsets and show TL-tetramer binding to correlate with expression of CD8β at low levels in the context of maintained CD8α expression (CD8α+CD8β^low). In addition, we found CD161−CD8α+CD8β^low populations to be significantly expanded in the peripheral blood of HIV-1 and hepatitis B (mean of 47 and 40% of CD161− T cells respectively) infected individuals. Such CD8αα expressing T cells are an effector-memory population (CD45RA−, CCR7−, CD62L−) that express markers of activation and maturation (HLA-DR+, CD28−, CD27−, CD57+) and are functionally distinct, expressing greater levels of TNF-α and IFN-γ on stimulation and perforin at rest than their CD8α+CD8β^high counterparts. Antigen-specific T cells in HLA-B^∗4201+HIV-1 infected patients are found within both the CD161−CD8α+CD8β^high and CD161−CD8α+CD8β^low populations. Overall we have clearly defined CD8αα expressing human T cell subsets using the TL-tetramer, and have demonstrated CD161−CD8α+CD8β^low populations, highly expanded in disease settings, to co-express CD8αβ and CD8αα. Co-expression of CD8αα on CD8αβ T cells may impact on their overall function in vivo and contribute to the distinctive phenotype of highly differentiated populations in HBV and HIV-1 infection.

Cowden syndrome

Cowden syndrome (CS) is a rare inherited condition characterised by multiple hamartomas in a variety of tissues from all three embryonic layers. It is a cancer predisposition syndrome with an increased risk of developing malignancy in many tissues but especially breast, thyroid and endometrium. It is inherited in an autosomal dominant manner with ∼80% of patients having a germ-line mutation of the PTEN tumour suppressor gene. Presenting signs and symptoms are highly non-specific. Nevertheless clinicians should be able to recognise this syndrome so that patients may be screened for cancerous growths and afforded the opportunity to have genetic testing to assist them and their family members in making medical management decisions. We present a review of this unusual but important condition with particular emphasis on the diagnostic criteria, clinical features, genetics, management and surveillance.

T cell sensitivity and the outcome of viral infection

The importance of CD8(+) T cells in the control of viral infections is well established. However, what differentiates CD8(+) T cell responses in individuals who control infection and those who do not is not well understood. 'Functional sensitivity' describes an important quality of the T cell response and is determined in part by the affinity of the T cell receptor for antigen. A more sensitive T cell response is generally believed to be more efficient and associated with better control of viral infection, yet may also drive viral mutation and immune escape. Various in vitro techniques have been used to measure T cell sensitivity; however, rapid ex vivo analysis of this has been made possible by the application of the 'magic' tetramer technology. Such tools have potentially important applications in the design and evaluation of vaccines.

Anti-Saccharomyces cerevisiae antibodies (ASCA) in Crohn's disease are associated with disease severity but not NOD2/CARD15 mutations

Anti-Saccharomyces cerevisiae antibodies (ASCAs) have been proposed as serological markers, which may differentiate Crohn's disease (CD) from ulcerative colitis (UC) and predict disease phenotype. Their importance in pathogenesis is unproven. We investigated the relationship between ASCAs, disease phenotype and NOD2/CARD15 genotype in CD and whether ASCAs were related to antibodies to other fungal proteins. Serum from 228 patients [143 CD, 75 UC, 10 with indeterminate colitis (IC)] and 78 healthy controls (HC) were assayed for ASCA. Antibodies (IgA, IgG) to other fungal proteins (Fusarium species ATC20334, Mycoprotein) were measured in the same samples using an in-house enzyme-linked immunosorbent assay (ELISA) assay. ASCAs were present in 57% of CD, 19% of UC, 30% of IC and 8% of HCs. ASCA-positive status was a predictor for CD with sensitivity of 57%, specificity of 87%, positive predictive value of 78% and negative predictive value of 68%. ASCA was associated with proximal (gastroduodenal and small bowel involvement) rather than purely colonic disease (P < 0.001) and with a more severe disease phenotype and requirement for surgery over a median follow-up time of 9 years (P < 0.0001). No associations with NOD2/CARD15 mutations were seen. There was no association between ASCA and antibodies to MP (IgA or IgG). These data implicate ASCA as a specific marker of disease location and progression in CD, emphasizing the heterogeneity within IBD.

College students' attitudes about AIDS: 1986 to 2000

College students' attitudes about AIDS and people with AIDS (PWAs) were measured over a 15-year period. The AIDS Attitude Scale, designed by Shrum, Turner, and Bruce (1989; AIDS Education and Prevention, 1, 222-230), was administered to introductory psychology students (n = 1,571) at one midsized southeastern university, thus allowing direct comparison of attitudes over time. Overall tolerance about AIDS and PWAs has increased from 1986 to 2000 and robust gender differences in attitudes have been apparent over time, with females expressing more tolerant attitudes. Concerns about contagion from casual contact are diminishing as well and perceived knowledge about AIDS has increased over time. Perceptions about personal susceptibility to HIV remain low and show little relationship to attitudes about AIDS and PWAs. These data may be used to help refine HIV prevention programs for college students and provide an example of a useful approach to monitor changes in attitudes over time.

Possible neuronal refractory or recovery artifacts associated with recording the mismatch negativity response

The mismatch negativity (MMN) is an event-related potential that involves a negative voltage shift of baseline electroencephalographic (EEG) activity in the approximate latency window of the N1 and P2 cortical potentials in response to new or novel sounds. The MMN is present at birth and has been hypothesized to serve as an automatic preconscious detector of changes in the auditory environment. Research paradigms used to extract the MMN response from EEG activity have a potential problem related to neuronal refractoriness or recovery. Both N1 and P2 are known to increase in amplitude with longer interstimulus intervals (ISIs). The MMN extraction procedures involve mathematical subtraction of waveforms elicited by standard sounds (with short ISIs) from those recorded to rare deviant sounds (with longer ISIs). Any ISI-dependent amplitude changes in N1 and/or P2 could therefore alter the morphology of the resulting difference wave and lead to misinterpretation of the nature of the underlying MMN generators. We tested 12 young females and found that the MMN can be influenced by ISI-dependent refractory effects that may modify the waveform morphology. This has important clinical implications since the MMN is being investigated as an assessment tool.

The consolidation/transition model in moral reasoning development

The consolidation/transition model conceptualizes development as entailing a cyclical pattern of alternating consolidation and transition phases and posits that stage advance is predicted by a specific distribution of reasoning across stages indicative of disequilibrium (more reasoning above than below the mode, with a high degree of mixture). The validity of this model was examined in the context of moral reasoning development with the use of standard statistical techniques as well as Bayesian techniques that can better account for classification error. In this longitudinal study. 64 children and adolescents participated in 5 annual administrations of the Moral Judgment Interview. The distribution of their reasoning across stages was used to predict subsequent development. The results support the hypotheses regarding cyclical patterns of change and predictors of stage transition and demonstrate the utility of Bayesian techniques for evaluating developmental change.

Parent and peer contexts for children's moral reasoning development

This study addressed the polarization among theoretical perspectives in moral psychology regarding the relative significance of parents and peers in children's developing moral maturity. The sample was composed of 60 target children from late childhood and midadolescence, 60 parents, and 60 friends who participated in parent/child and friend/child dyadic discussions of a series of moral conflicts. The quality of parents' and friends' verbal interactions, ego functioning, and level of moral reasoning in these discussions was used to predict the rate of children's moral reasoning development over a 4-year longitudinal interval. Results revealed that interactions with both parents and peers were predictive of children's development but that these two types of relationships influence development in rather different ways. Implications of the findings for the understanding of these socialization agents' roles in moral development are discussed.

Parent and peer contexts for children's moral reasoning development

This study addressed the polarization among theoretical perspectives in moral psychology regarding the relative significance of parents and peers in children's developing moral maturity. The sample was composed of 60 target children from late childhood and midadolescence, 60 parents, and 60 friends who participated in parent/child and friend/child dyadic discussions of a series of moral conflicts. The quality of parents' and friends' verbal interactions, ego functioning, and level of moral reasoning in these discussions was used to predict the rate of children's moral reasoning development over a 4-year longitudinal interval. Results revealed that interactions with both parents and peers were predictive of children's development but that these two types of relationships influence development in rather different ways. Implications of the findings for the understanding of these socialization agents' roles in moral development are discussed.

Apnoeic episodes in a patient with Chiari type I malformation

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Naturalistic conceptions of moral maturity

By examining naturalistic conceptions of moral maturity, this project sought a more comprehensive understanding of moral excellence than is evident in dominant theories of moral development. Studies 1 and 2 involved different samples of 120 adults (17-25, 35-55, and 65+ years). Study 3 involved a sample of 180 undergraduates. In Study 1, a free-listing procedure was used to generate the attributes of a highly moral person as well as those for two related person-concepts. In Study 2, a rating procedure for these attributes was used to generate a prototype of the moral person-concept. In Study 3, a similarity-sorting task was used to uncover people's implicit typology of moral maturity. The findings indicate that naturalistic notions of moral excellence not only contain themes of principled reasoning but also reference aspects of moral character and virtue that enlarge our understanding of the psychological functioning of the mature moral agent.

Naturalistic conceptions of moral maturity

By examining naturalistic conceptions of moral maturity, this project sought a more comprehensive understanding of moral excellence than is evident in dominant theories of moral development. Studies 1 and 2 involved different samples of 120 adults (17-25, 35-55, and 65+ years). Study 3 involved a sample of 180 undergraduates. In Study 1, a free-listing procedure was used to generate the attributes of a highly moral person as well as those for two related person-concepts. In Study 2, a rating procedure for these attributes was used to generate a prototype of the moral person-concept. In Study 3, a similarity-sorting task was used to uncover people's implicit typology of moral maturity. The findings indicate that naturalistic notions of moral excellence not only contain themes of principled reasoning but also reference aspects of moral character and virtue that enlarge our understanding of the psychological functioning of the mature moral agent.

Role of the HAP1 protein in repair of oxidative DNA damage and regulation of transcription factors

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Identification of critical active-site residues in the multifunctional human DNA repair enzyme HAP1

All organisms express dedicated repair enzymes for counteracting the cytotoxic and mutagenic potential of apurinic/apyrimidinic (AP) lesions, which would otherwise pose a serious threat to genome integrity. We present the predicted three-dimensional structure of the major human AP site-specific DNA repair endonuclease, HAP1, and show that an aspartate/histidine pair, in conjunction with a metal ion-coordinating glutamate residue, are critical for catalyzing the multiple repair activities of HAP1. We suggest that this catalytic mechanism is conserved in certain reverse transcriptases, but is distinct from the two metal ion-mediated mechanism defined for other hydrolytic nucleases.

Site-directed mutagenesis of the human DNA repair enzyme HAP1: identification of residues important for AP endonuclease and RNase H activity

HAP1 protein, the major apurinic/apyrimidinic (AP) endonuclease in human cells, is a member of a homologous family of multifunctional DNA repair enzymes including the Escherichia coli exonuclease III and Drosophila Rrp1 proteins. The most extensively characterised member of this family, exonuclease III, exhibits both DNA- and RNA-specific nuclease activities. Here, we show that the RNase H activity characteristic of exonuclease III has been conserved in the human homologue, although the products resulting from RNA cleavage are dissimilar. To identify residues important for enzymatic activity, five mutant HAP1 proteins containing single amino acid substitutions were purified and analysed in vitro. The substitutions were made at sites of conserved amino acids and targeted either acidic or histidine residues because of their known participation in the active sites of hydrolytic nucleases. One of the mutant proteins (replacement of Asp-219 by alanine) showed a markedly reduced enzymatic activity, consistent with a greatly diminished capacity to bind DNA and RNA. In contrast, replacement of Asp-90, Asp-308 or Glu-96 by alanine led to a reduction in enzymatic activity without significantly compromising nucleic acid binding. Replacement of His-255 by alanine led to only a very small reduction in enzymatic activity. Our data are consistent with the presence of a single catalytic active site for the DNA- and RNA-specific nuclease activities of the HAP1 protein.

A role for the human DNA repair enzyme HAP1 in cellular protection against DNA damaging agents and hypoxic stress

The HAP1 protein (also known as APE/Ref-1) is a bifunctional human nuclear enzyme required for repair of apurinic/apyrimidinic sites in DNA and reactivation of oxidized proto-oncogene products. To gain insight into the biological roles of HAP1, the effect of expressing antisense HAP1 RNA in HeLa cells was determined. The constructs for antisense RNA expression consisted of either a full-length HAP1 cDNA or a genomic DNA fragment cloned downstream of the CMV promoter in pcDNAneo. Stable HeLa cell transfectants expressing HAP1 antisense RNA were found to express greatly reduced levels of the HAP1 protein compared to equivalent sense orientation and vector-only control transfectants. The antisense HAP1 transfectants exhibited a normal growth rate, cell morphology and plating efficiency, but were hypersensitive to killing by a wide range of DNA damaging agents, including methyl methanesulphonate, hydrogen peroxide, menadione, and paraquat. However, survival after UV irradiation was unchanged. The antisense transfectants were strikingly sensitive to changes in oxygen tension, exhibiting increased killing compared to controls following exposure to both hypoxia (1% oxygen) and hyperoxia (100% oxygen). Consistent with a requirement for HAP1 in protection against hypoxic stress, expression of the HAP1 protein was found to be induced in a time-dependent manner in human cells during growth under 1% oxygen. The possible involvement of a depletion of cellular glutathione being linked to the hypoxic stress-sensitive phenotype of the antisense HAP1 transfectants came from the finding that they also exhibited hypersensitivity to buthionine sulphoximine, an inhibitor of glutathione biosynthesis. We conclude that the HAP1 protein is a key factor in cellular protection against a wide variety of cellular stresses, including DNA damage and a change in oxygen tension.

Identification of residues in the human DNA repair enzyme HAP1 (Ref-1) that are essential for redox regulation of Jun DNA binding

The DNA binding activity of the c-jun proto-oncogene product is inhibited by oxidation of a specific cysteine residue (Cys-252) in the DNA binding domain. Jun protein inactivated by oxidation of this residue can be efficiently reactivated by a factor from human cell nuclei, recently identified as a DNA repair enzyme (termed HAP1 or Ref-1). The HAP1 protein consists of a core domain, which is highly conserved in a family of prokaryotic and eukaryotic DNA repair enzymes, and a 61-amino-acid N-terminal domain absent from bacterial homologs such as Escherichia coli exonuclease III. The eukaryote-specific N-terminal domain was dispensable for the DNA repair functions of the HAP1 protein but was essential for reactivation of the DNA binding activity of oxidized Jun protein. Consistent with this finding, exonuclease III protein could not reactive Jun. A minimal 26-residue region of the N-terminal domain proximal to the core of the HAP1 enzyme was required for redox activity. By site-directed mutagenesis, cysteine 65 was identified as the redox active site in the HAP1 enzyme. In addition, it is proposed that cysteine 93 interacts with the redox active site, probably via disulfide bridge formation. It is concluded that the HAP1 protein has evolved a novel redox activation domain capable of regulating the DNA binding activity of a proto-oncogene product which is not essential for its DNA repair functions. Identification of a putative active site cysteine residue should facilitate analysis of the mechanism by which the HAP1 protein may alter the redox state of a wide range of transcription factors.

Behçet's disease presenting with mononeuritis multiplex [corrected]

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A longitudinal study of moral reasoning

Several issues concerning Gilligan's model of moral orientations and Kohlberg's models of moral stages and moral orientations were examined in a longitudinal study with 233 subjects (from 78 families) who ranged in age from 5 to 63 years. They participated in 2 identical interviews separated by a 2-year interval. In each interview, they discussed hypothetical dilemmas and a personally generated real-life dilemma, which were scored for both moral stage and moral orientation (both Gilligan's and Kohlberg's typologies). Results revealed few violations of the stage sequence over the longitudinal interval, supporting Kohlberg's moral stage model. Sex differences were almost completely absent for both Gilligan's and Kohlberg's moral orientations, although there were clear developmental trends. Hypothetical and real-life dilemmas elicited different moral orientations, especially in terms of Kohlberg's typology. The interrelations between the 2 models of moral orientations were generally weak, indicating that they are not synonymous.

Disseminated infection caused by urease-negative Cryptococcus neoformans

We report a case of fungemia and disseminated disease caused by a urease-negative strain of Cryptococcus neoformans in a patient with the acquired immune deficiency syndrome. Except for failure to hydrolyze urea, the microbiological characteristics of the isolate were typical of C. neoformans. Laboratory specialists should be aware of the occurrence of atypical strains of C. neoformans, particularly those recovered from patients with the acquired immune deficiency syndrome.

Effect of nifedipine on arrhythmias in the acute phase of myocardial infarction

In a double-blind placebo-controlled trial to study the effect of nifedipine on ventricular arrhythmias among patients with acute myocardial infarction, 434 patients with suspected myocardial infarction were randomized within 6 h from the onset of chest pain to treatment with nifedipine (p = 217) or placebo (p = 217). During the 48-h treatment period, a 10-mg capsule containing active drug or placebo was administered sublingually every 4 h for 24 h, then orally every 4 h for the next 24 h. Acute myocardial infarction was confirmed in 295 patients (146 in the nifedipine group and 149 in the placebo group). Twenty-four hour ECG tape analysis during 1-5 h from onset of chest pain showed that there was no significant difference in the number of patients with ventricular ectopics, ventricular couplets, ventricular tachycardia (3-9 beats), self terminating or sustained ventricular tachycardia between the two treatment groups. Also during the greater than 5-24 h from onset of chest pain, the numbers of patients with ventricular ectopics, multifocal, bigeminal or couplets, self-terminating ventricular tachycardia or sustained ventricular tachycardia did not differ significantly. However, there was a significant reduction in the number of patients with short runs of ventricular tachycardia (3-9 beats) in the nifedipine-treated group. There was no significant difference among patients with ventricular fibrillation between the two treatment groups.

Effect of nifedipine on enzymatically estimated infarct size in the early phase of acute myocardial infarction

In a double blind placebo controlled trial, 434 patients with suspected myocardial infarction were randomised to treatment with nifedipine (n = 217) or placebo (n = 217) within six hours from the onset of chest pain. During the treatment period of 48 hours, a 10 mg capsule containing nifedipine or placebo was given sublingually every four hours for 24 hours, then orally every four hours for the next 24 hours. Acute myocardial infarction was confirmed in 295 patients (146 in the nifedipine group and 149 in the placebo group). The median delay time to intervention with nifedipine in patients with acute myocardial infarction was 111 minutes. Infarct size was assessed by the estimation of release of creatine kinase isoenzyme MB and creatine kinase from blood samples taken every four hours for 48 hours. The total mean (SEM) creatine kinase MB released was 406.4 (27.2) IU/l in the nifedipine group and 345.7 (20.5) IU/l in the placebo group. Total mean (SEM) creatine kinase released was 2749.6 (165.1) IU/l in the nifedipine group and 2698.4 (145.9) IU/l in the placebo group. In hospital mortality was similar for both the nifedipine and placebo groups (6.6% and 5.8% respectively). Treatment with nifedipine in the early phase of acute myocardial infarction seems to have no effect on enzymatically measured infarct size.

Self-reported stress symptoms in farmers

The self-reported incidence of stress-related symptoms was studied in 817 farm men and women and 109 urban residents. Close to 50% of the farm sample reported the frequent to constant occurrence of the symptoms of trouble relaxing, loss of temper, and fatigue. Over 30% of the farmers reported similar occurrence rates for six additional symptoms. Self-reported symptom rates were significantly higher in farm women than in farm men, higher in younger farmers, higher in mixed farming operations, and higher in farmers who were holding off-farm employment. Symptom scores were significantly higher in the farmers compared to the urban sample. A stepwise discriminant analysis showed that scores on five symptoms were able to distinguish meaningfully between farm and urban groups. It was suggested that the chronic stress associated with the current farm financial crisis may be causing a high self-reported incidence of symptoms among farmers.

Intravenous catheter-associated Malassezia furfur fungemia

Malassezia furfur, a lipophilic yeast that is the etiologic agent of tinea versicolor, has not been considered as a cause of serious illness in adults in the past. Two adults are described in whom Malassezia furfur fungemia developed while receiving total parenteral nutrition supplemented with lipids. The organism was identified in blood cultures from both patients only after isolation media were supplemented with a source of fatty acids. Because M. furfur will grow only in media supplemented with fatty acids, clinicians should alert the laboratory whenever a lipophilic organism is suspected to be present in blood cultures.

Successful treatment by doxycycline of endocarditis caused by ornithosis

The case of a 59 year old man with ornithosis endocarditis and a history of contact with pheasants is reported. Treatment with oxytetracycline was not tolerated and so doxycycline was substituted. Over the two year follow up the patient's clinical condition and serial echocardiographic appearances improved and Chlamydia psittaci complement fixation titres returned to normal. Valve replacement was not required.

Reduced cellular immunity to varicella zoster virus during treatment for acute lymphoblastic leukemia of childhood: in vitro studies of possible mechanisms

To determine the effect of antileukemic therapy on preexisting immunity to varicella zoster virus, we studied 20 children with acute lymphoblastic leukemia maintained in complete continuous remission for greater than 1 year. Cellular immunity was tested by lymphocyte proliferation in response to varicella antigen. Antiviral antibody was measured using the fluorescent antibody to membrane antigen technique. Reduced lymphocyte proliferation was found in 9 of 16 seropositive patients when compared to an age-related control group. On the other hand, antibody titers in patients receiving chemotherapy remained positive and were essentially unchanged from pretreatment values. Shingles occurred in two of nine children with diminished and none of seven patients with normal cellular immunity, suggesting that proliferative responses to varicella antigen may have predicative value in identifying patients at risk for viral reactivation. Additional studies were done to determine if defective antigen presentation or reduced lymphocyte responder-cell frequency could account for the subnormal proliferative responses. Intact presentation of varicella antigens by patient mononuclear cells to parental, virus-specific T-cell blasts suggested that antigen processing was not defective. However, varicella-specific responder-cell frequencies measured by limiting dilution analysis were found to be depressed in most patients, including some with normal proliferative responses. Our findings indicate that therapy for acute lymphoblastic leukemia in children can be associated with depressed cell-mediated immunity to varicella zoster virus even though patients remain seropositive. Further studies suggest that while monocyte-mediated antigen presentation remains intact, virus-specific lymphocyte numbers decline and probably contribute to decreased cellular immunity to varicella zoster virus in children being treated for leukemia.

Intravenous catheter-associated fungemia due to Candida rugosa

We report a case of intravenous catheter-associated fungemia caused by Candida rugosa; this is the first report of such an infection in a human. Multiple cultures of blood taken over a 24-h period and of the intravenous catheter tip were positive for this unusual isolate. The patient was treated with intravenous amphotericin B and made an uneventful recovery. Intravenous cannulae and other intravascular devices are well recognized as potential sites of intravascular infection by a variety of microorganisms, including several Candida species; however, fungemia caused by C. rugosa has not been reported.

Free and total putrescine in cerebrospinal fluid quantified by reversed-phase liquid chromatography

This is a simple, rapid, sensitive method for routine quantification of the polyamine putrescine (1,4-diaminobutane) in cerebrospinal fluid. Sample preparation involves protein precipitation, acid hydrolysis for 18 h (if total putrescine is to be measured), pre-column derivatization with o-phthalaldehyde, and extraction into acetonitrile. The derivative is separated and quantified by "high-performance" liquid chromatography on a reversed-phase C18 radial-compression column. A single chromatographic run takes less than 18 min. Putrescine concentrations as low as 50 nmol/L in cerebrospinal fluid can be detected.

Free and total putrescine in cerebrospinal fluid quantified by reversed-phase liquid chromatography

This is a simple, rapid, sensitive method for routine quantification of the polyamine putrescine (1,4-diaminobutane) in cerebrospinal fluid. Sample preparation involves protein precipitation, acid hydrolysis for 18 h (if total putrescine is to be measured), pre-column derivatization with o-phthalaldehyde, and extraction into acetonitrile. The derivative is separated and quantified by "high-performance" liquid chromatography on a reversed-phase C18 radial-compression column. A single chromatographic run takes less than 18 min. Putrescine concentrations as low as 50 nmol/L in cerebrospinal fluid can be detected.

Trait anxiety in mothers: differences associated with employment status, family size and age of children

The State-Trait Anxiety Inventory was administered to 345 adult women to determine if anxiety was related to employment status, number of children, and age of children. Respondents were categorized as not employed, employed part-time, or employed full-time and also in terms of number and ages of children. The results indicated that women not employed outside their homes have slightly higher levels of anxiety than the employed women. A significant relationship between ages of children and anxiety was also obtained with Trait-anxiety being highest in women with all children between 2 and 5 yr. of age and lowest in women whose children were all older than 5. The importance of the ages of children and the impact of employment status in contributing to maternal stress are discussed.

Bacteriocidal properties of platelet concentrates

Platelet concentrates were contaminated with predetermined numbers of bacteria isolated from patients. Staphylococcus epidermidis and Pseudomonas aeruginosa organisms were killed if the number introduced was less than 10(3). When 10(4) through 10(6) organisms were added, their growth was depressed for 24 hours and then slowly resumed. If more than 10(7) organisms were used, a slow and progressive growth occurred. After the concentrates were contaminated with Staphylocoecus aureus, slow progressive growth occurred regardless of the size of the inoculum. Cultures taken from sample phlebotomies performed on a few donors showed that the number and type of organisms released into the blood during the venepuncture are such that they could usually, but not always, be inactivated by the bacteriocidal property of the platelet packs. This bacteriocidal property will usually allow the platelet packs to be stored at room temperature for considerable amounts of time with relative safety. Bacterial growth will normally occur only when the number of organisms introduced during the venepuncture is quite large, and growth will usually occur during the first 24 hours.