Associations between sleep patterns, smoking, and alcohol use among older adults in Canada: Insights from the Canadian Longitudinal Study on Aging (CLSA).

Poor sleep is associated with chronic health conditions among older adults. As substance use rates increase in this population, age-related physiological and cognitive declines may exacerbate its detrimental consequences, including sleep problems. We analyzed cross-sectional associations between sleep patterns, smoking, and alcohol use using baseline data from 30,097 community-dwelling Canadian adults aged 45-85 years from the Canadian Longitudinal Study on Aging. Insomnia symptoms (difficulties falling/staying asleep), sleep duration (short:<6h; long:>8h), and sleep satisfaction(dissatisfied/neutral/satisfied) were measured. Smoking and alcohol-use frequency (past 12 months), average daily amount (past 30 days), and binge drinking (past 12 months) were self-reported, and associations were examined using modified Poisson regression. Approximately 23% of participants had insomnia symptoms, and 26% reported sleep dissatisfaction. 91% of participants were current non-smokers, whereas 7% reported smoking daily. Over 50% drank ≤ 2 drinks daily, and 3% reported binge drinking. There was a higher adjusted prevalence of insomnia among daily smokers (PR = 1.10, 95% CI = 1.00-1.21) and binge drinkers (PR = 1.21, 95% CI = 1.02-1.43). Odds of short sleep duration were lower among regular drinkers (COR = 0.71, 95% CI = 0.56-0.90) and higher among daily smokers (COR = 1.19, 95% CI = 1.01-1.40). Heavy and frequent smoking and alcohol use are associated with both insomnia symptoms and sleep dissatisfaction, but not consistently with sleep duration. Further longitudinal investigation of this relationship in aging populations is needed in clinical and public health settings to infer the extent of causality and design effective public health interventions in this vulnerable population.

T-cell release of granulysin contributes to host defense in leprosy.

A novel mechanism by which T cells contribute to host defense against microbial pathogens is release of the antimicrobial protein granulysin. We investigated the role of granulysin in human infectious disease using leprosy as a model. Granulysin-expressing T cells were detected in cutaneous leprosy lesions at a six-fold greater frequency in patients with the localized tuberculoid as compared with the disseminated lepromatous form of the disease. In contrast, perforin, a cytolytic molecule that colocalizes with granulysin in cytotoxic granules, was expressed at similar levels across the spectrum of disease. Within leprosy lesions, granulysin colocalized in CD4+ T cells and was expressed in CD4+ T-cell lines derived from skin lesions. These CD4+ T-cell lines lysed targets by the granule exocytosis pathway and reduced the viability of mycobacteria in infected targets. Given the broad antimicrobial spectrum of granulysin, these data provide evidence that T-cell release of granulysin contributes to host defense in human infectious disease.

Evidence for clonal selection of gamma/delta T cells in response to a human pathogen.

T cells bearing gamma/delta antigen receptors comprise a resident population of intraepithelial lymphocytes in organs such as skin, gut, and lungs, where they are strategically located to contribute to the initial defense against infection. An important unsolved question about antigen-driven gamma/delta T cell responses regards the breadth of their T cell receptor (TCR) repertoire, since many specific epithelial compartments in mice display limited diversity. We have examined the diversity of TCR delta gene expression among human gamma/delta T cells from skin lesions induced by intradermal challenge with Mycobacterium leprae. We show that the vast majority of gamma/delta cells from M. leprae lesions use either V delta 1-J delta 1 or V delta 2-J delta 1 gene rearrangements and, within a given region of the lesion, display limited junctional diversity. This contrasts markedly with the extensive diversity of gamma/delta T cells from peripheral blood of these same individuals, as well as skin from normal donors. These results indicate that the gamma/delta response to M. leprae involves the selection of a limited number of clones from among a diverse repertoire, probably in response to specific mycobacterial and/or host antigens.

Analysis of naturally occurring delayed-type hypersensitivity reactions in leprosy by in situ hybridization.

Analysis of tissue lesions of the major reactional states of leprosy was undertaken to study the immune mechanisms underlying regulation of cell-mediated immunity and delayed-type hypersensitivity (DTH) in man. In situ hybridization hybridization of reversal reaction biopsy specimens for INF-gamma mRNA expression revealed a 10-fold increase in specific mRNA-containing cells over that observed in unresponsive lepromatous patients. Expression of huHF serine esterase, a marker for T cytotoxic cells, were fourfold increased in reversal reaction and tuberculoid lesions above that detected in unresponsive lepromatous individuals. Immunohistology of reversal reactions confirmed a selective increase of Th and T cytotoxic cells in the cellular immune response. Of interest, the microanatomic location of these serine esterase mRNA-containing cells was identical to the distribution of CD4+ cells. Analysis of erythema nodosum leprosum (ENL) lesions revealed differences in the underlying immune processes in comparison with reversal reaction lesions. Although phenotypic Th cells predominated in ENL lesions, IFN-gamma and serine esterase gene expression were markedly reduced. We suggest that reversal reactions represent a hyperimmune DTH response characterized by a selective increase of CD4+ IFN-gamma producing cells and T cytotoxic cells, which result in the clearing of bacilli and concomitant tissue damage. In contrast, ENL reactions may be viewed as a transient diminution of Ts cells and activity leading to a partial and transient augmentation in cell-mediated immunity, perhaps sufficient to result in antibody and immune complex formation, but insufficient to clear bacilli from lesions.

Defining protective responses to pathogens: cytokine profiles in leprosy lesions.

The immunological mechanisms required to engender resistance have been defined in few infectious diseases of man, and the role of specific cytokines is unclear. Leprosy presents clinically as a spectrum in which resistance correlates with cell-mediated immunity to the pathogen. To assess in situ cytokine patterns, messenger RNA extracted from leprosy skin biopsy specimens was amplified by the polymerase chain reaction with 14 cytokine-specific primers. In lesions of the resistant form of the disease, messenger RNAs coding for interleukin-2 and interferon-gamma were most evident. In contrast, messenger RNAs for interleukin-4, interleukin-5, and interleukin-10 predominated in the multibacillary form. Thus, resistance and susceptibility were correlated with distinct patterns of cytokine production.

Outcome of cardiac arrests attended by emergency medical services staff at community outpatient dialysis centers.

Cardiac arrest is the leading cause of death among dialysis patients in the United States. We measured the outcome of cardiac arrests attended by Emergency Medical Services (EMS) staff at hemodialysis facilities in a 14-year population-based retrospective study to identify cardiac arrest cases at a dialysis unit. Associated factors were determined using unconditional logistic regression. Of the 102 cardiac arrests identified around the time of dialysis, 10 occurred before, 72 during, and 20 after hemodialysis. The initial measured abnormality was ventricular fibrillation or tachycardia in 72 cases. Of those who survived transportation to a hospital, survival to discharge was 24 with 15% survival at 1 year. Compared to arrests that occurred prior to dialysis, the odds of ventricular fibrillation were 5-fold greater in patients on dialysis but 14-fold greater in those arresting after dialysis. One-third of cases occurred after the introduction of automated external defibrillators, and in half of the cases these devices were attached prior to EMS arrival. Once these devices were attached, most were used for defibrillation. We conclude that ventricular arrhythmias are the predominant features among arrested in-center dialysis patients with most occurrences during dialysis. The role of these devices in dialysis units will need a larger study to evaluate their efficacy.

Survival and variability over time from out of hospital cardiac arrest across large geographically diverse communities participating in the Resuscitation Outcomes Consortium.

BACKGROUND: The Resuscitation Outcomes Consortium (ROC)epidemiological registry (Epistry) provides opportunities to assess trends in out-of-hospital cardiac arrest treatment and outcomes. METHODS: Patient, event, system, treatment, and outcome data from adult (≥18 years) out-of-hospital cardiac arrest (OHCA) from 10 geographically diverse North American ROC sites over four 12-month epochs, from July 1, 2011 to June 30, 2015, were assessed. Descriptive statistics were used to characterize the sample and logistic regression assessed the association of study epoch and key covariates on survival. RESULTS: Overall, 85,553 patients were assessed by Emergency Medical Services (EMS) and 45,516 (53.2%, site range 30.4%-69.9%) had resuscitation attempted by EMS. Patient and event characteristics were consistent except for increases in bystander CPR (41.3%-44.9%) and bystander AED application (3.9%-5.2%). EMS CPR depth and compression fraction increased while pre-shock pause interval decreased. Targeted temperature management was performed in 51.1% of admitted patients and early coronary angiography in 30.2%. Survival to hospital discharge improved (from 10.9% to 11.3% across epochs) with epoch significantly associated with survival (p < 0.001) showing an increasing trend in survival over time. (p = 0.02). Marked site variation in survival persisted within and across epochs (overall site range: 4.2%-19.8%). Patients with an initially shockable rhythm (VT/VF) had an overall survival of 32.2% (site range: 11.9%-47.1%) while survival in bystander witnessed VT/VF was 35.8% (site range: 12.9%-53.1%). CONCLUSIONS: Survival from adult OHCA in multiple large geographically-separate sites improved over the study period. Marked site differences in survival persist and addressing this variation is essential to improve outcomes from OHCA across North America.

Interferon-gamma differentially regulates interleukin-12 and interleukin-10 production in leprosy.

The ability of monocytes to influence the nature of the T cell response to microbial pathogens is mediated in part by the release of cytokines. Of particular importance is the release of IL-12 and IL-10 by cells of the monocyte/macrophage lineage upon encountering the infectious agent. IL-12 promotes cell mediated immunity (CMI) to intracellular pathogens by augmenting T-helper type 1 responses, whereas IL-10 downregulates these responses. The ability of IFN-gamma to modulate the balance between IL-12 and IL-10 production was examined by studying leprosy as a model. In response to Mycobacterium leprae stimulation, IFN-gamma differentially regulated IL-12 and IL-10 production resulting in upregulation of IL-12 release and downregulation of IL-10 release. Furthermore, we determined that the mechanism by which IFN-gamma downregulates IL-10 was through the induction of IL-12. The data suggest a model of lymphocyte-monocyte interaction whereby the relative presence or absence of IFN-gamma in the local microenvironment is a key determinant of the type of monocyte cytokine response, and hence the degree of CMI in the host response to infection.

The contribution of individual and pairwise combinations of SNPs in the APOA1 and APOC3 genes to interindividual HDL-C variability.

Apolipoproteins (apo) A-I and C-III are components of high-density lipoprotein-cholesterol (HDL-C), a quantitative trait negatively correlated with risk of cardiovascular disease (CVD). We analyzed the contribution of individual and pairwise combinations of single nucleotide polymorphisms (SNPs) in the APOA1/APOC3 genes to HDL-C variability to evaluate (1) consistency of published single-SNP studies with our single-SNP analyses; (2) consistency of single-SNP and two-SNP phenotype-genotype relationships across race-, gender-, and geographical location-dependent contexts; and (3) the contribution of single SNPs and pairs of SNPs to variability beyond that explained by plasma apo A-I concentration. We analyzed 45 SNPs in 3,831 young African-American (N=1,858) and European-American (N=1,973) females and males ascertained by the Coronary Artery Risk Development in Young Adults (CARDIA) study. We found three SNPs that significantly impact HDL-C variability in both the literature and the CARDIA sample. Single-SNP analyses identified only one of five significant HDL-C SNP genotype relationships in the CARDIA study that was consistent across all race-, gender-, and geographical location-dependent contexts. The other four were consistent across geographical locations for a particular race-gender context. The portion of total phenotypic variance explained by single-SNP genotypes and genotypes defined by pairs of SNPs was less than 3%, an amount that is miniscule compared to the contribution explained by variability in plasma apo A-I concentration. Our findings illustrate the impact of context-dependence on SNP selection for prediction of CVD risk factor variability.

Clinical depression and risk of out-of-hospital cardiac arrest.

BACKGROUND: The association of depression with coronary heart disease-related mortality has been widely recognized. This finding may partly reflect an association between depression and sudden death, in part because the imbalance between sympathetic and parasympathetic tone is altered in depressed subjects. We, thus, investigated whether the presence and severity of clinical depression was associated with a higher risk of sudden cardiac death. METHODS: We used data from a population-based case-control study of risk factors for incident out-of-hospital cardiac arrest (CA) conducted among enrollees of a health maintenance organization in western Washington State. Cases (n = 2228) were aged 40 to 79 years and experienced CA between January 1, 1980, and December 31, 1994. Controls (n = 4164) were a stratified random sample of enrollees defined by calendar year, age, sex, and prior heart disease. Clinical depression was defined as physician diagnosis of depression or use of antidepressant treatment within the year before the event. Referral to mental health clinics or hospitalization for depression defined severe depression. RESULTS: Clinically depressed patients had a higher odds ratio (OR) of CA (1.88; 95% confidence interval [CI], 1.59-2.23), which persisted after adjustment for confounders (OR, 1.43; 95% CI, 1.18-1.73). The association was observed in both sexes, in various age groups, and in subjects with prior physician-diagnosed heart disease (OR, 1.27; 95% CI, 1.01-1.60) and without prior physician-diagnosed heart disease (OR, 1.71; 95% CI, 1.22-2.41) (P = .13 for the interaction). Compared with nondepressed subjects, the risk of CA was increased in less severely depressed subjects (OR, 1.30; 95% CI, 1.04-1.63) and further increased in severely depressed subjects (OR, 1.77; 95% CI, 1.28-2.45) (P<.001 for trend). CONCLUSION: Clinical depression may be associated with a higher risk of CA independently of established coronary heart disease risk factors.

Circulating microRNAs and sudden cardiac arrest outcomes.

AIM: MicroRNAs (miRNAs) have regulatory functions in organs critical in resuscitation from sudden cardiac arrest due to ventricular fibrillation (VF-SCA); therefore, circulating miRNAs may be markers of VF-SCA outcome. METHODS: We measured candidate miRNAs (N=45) in plasma using qRT-PCR among participants of a population-based VF-SCA study. Participants were randomly selected cases who died in the field (DF, n=15), died in hospital (DH, n=15), or survived to discharge (DC, n=15), and, age-, sex-, and race-matched controls (n=15). MiRNA levels were compared using ANOVA, t-tests, and fold-changes. RESULTS: Mean age of groups ranged from 66.9 to 69.7. Most participants were male (53-67%) and white (67%). Comparing cases to controls, plasma levels of 17 miRNAs expressed in heart, brain, liver, and other tissues (including miR-29c, -34a, -122, -145, -200a, -210, -499-5p, and -663b) were higher and three non-specific miRNAs lower (miR-221, -330-3p, and -9-5p). Among DH or DC compared with DF cases, levels of two miRNAs (liver-specific miR-122 and non-specific miR-205) were higher and two heart-specific miRNAs (miR-208b and -499-5p) lower. Among DC vs. DF cases, levels of three miRNAs (miR-122, and non-specific miR-200a and -205) were higher and four heart-specific miRNAs (miR-133a, -133b, -208b, and -499-5p) lower. Among DC vs. DH cases, levels of two non-specific miRNAs (miR-135a and -9-3p) were lower. CONCLUSIONS: Circulating miRNAs expressed in heart, brain, and other tissues differ between VF-SCA cases and controls and are related to resuscitation outcomes. Measurement of miRNAs may clarify mechanisms underlying resuscitation, improve prognostication, and guide development of therapies. Results require replication.

Lack of correlation between ACAT mRNA expression and cholesterol esterification in primary liver cells.

A partial rabbit cDNA clone (14b) for ACAT has been characterized and used to demonstrate that hepatic and aortic ACAT mRNA14b abundance increased 2-3-fold in rabbits receiving a high fat/high cholesterol-diet compared to chow fed animals (Pape et al. (1995) J. Lipid Res. 36, 823-838). Because of those data we hypothesized that increased hepatic cholesteryl ester mass and synthesis rates in rabbit liver cells are associated with an increase in ACAT mRNA14b levels. To test this hypothesis we altered cellular cholesteryl ester mass and synthesis rates in primary parenchymal and nonparenchymal cells using various extracellular agents and measured the accumulated mass of ACAT mRNA14b. Parenchymal cells incubated with rabbit beta VLDL or mevalonolactone displayed a 6-10-fold increase in cellular cholesteryl ester mass over a three day treatment with no significant changes in cellular free cholesterol, triacylglycerols, or ACAT mRNA14b levels; HMG CoA reductase and LDL receptor mRNA mass decreased initially as a result of cholesteryl ester loading. Treatment of parenchymal cells with CI-976, an ACAT inhibitor, showed a marked reduction in cholesteryl ester synthetic rate compared to beta VLDL controls but displayed no change in ACAT mRNA14b levels. A mixed population of rabbit hepatic nonparenchymal cells was incubated with beta VLDL for 24 h in culture which resulted in a 6-fold increase in cellular cholesteryl ester mass; there was no change in ACAT mRNA14b levels. In an in vivo study, rabbits consuming a high fat/high cholesterol-diet for three weeks showed a 10-fold increase in hepatic cholesteryl ester with no significant changes in ACAT mRNA14b levels. Together these data indicate that rabbit liver cellular cholesteryl ester mass increases of up to 10-fold are not correlated with ACAT mRNA14b changes. Thus, hepatic ACAT mRNA14b expression and cellular cholesterol esterification do not appear to be coordinately regulated at this level of cholesteryl ester loading.

Dispatcher-assisted cardiopulmonary resuscitation and survival in cardiac arrest.

BACKGROUND: Early cardiopulmonary resuscitation (CPR) improves survival in out-of-hospital cardiac arrest, and dispatcher-delivered instruction in CPR can increase the proportion of arrest victims who receive bystander CPR before emergency medical service (EMS) arrival. However, little is known about the survival effectiveness of dispatcher-delivered telephone CPR instruction. METHODS AND RESULTS: We evaluated a population-based cohort of EMS-attended adult cardiac arrests (n=7265) from 1983 through 2000 in King County, Washington, to assess the association between survival to hospital discharge and 3 distinct CPR groups: no bystander CPR before EMS arrival (no bystander CPR), bystander CPR before EMS arrival requiring dispatcher instruction (dispatcher-assisted bystander CPR), and bystander CPR before EMS arrival not requiring dispatcher instruction (bystander CPR without dispatcher assistance). In this cohort, 44.1% received no bystander CPR before EMS arrival, 25.7% received dispatcher-assisted bystander CPR, and 30.2% received bystander CPR without dispatcher assistance. Overall survival was 15.3%. Using no bystander CPR as the reference group, the multivariate adjusted odds ratio of survival was 1.45 (95% confidence interval [CI], 1.21, 1.73) for dispatcher-assisted bystander CPR and 1.69 (95% CI, 1.42, 2.01) for bystander CPR without dispatcher assistance. CONCLUSION: Dispatcher-assisted bystander CPR seems to increase survival in cardiac arrest.

A prospective study of tender points and fibromyalgia during and after an acute viral infection.

BACKGROUND: Tender points (TPs) and fibromyalgia (FM) may be precipitated by infections, but the frequency, associated characteristics, and predictors of these outcomes are unknown. OBJECTIVES: To determine if acute infectious mononucleosis (AIM) is associated with the development of TPs or FM acutely or during the subsequent 6 months; if demographic, clinical, or psychosocial features predict TPs or FM; and if TPs or FM correlate with nonrecovery. METHODS: A total of 150 subjects diagnosed as having AIM were assessed with physical examinations (including palpation of 18 TPs), laboratory tests, and measures of psychosocial and somatic functioning at enrollment and at 2 and 6 months. Subjects also completed a structured psychiatric interview at the initial evaluation. RESULTS: At presentation and at 2 and 6 months, the mean TP counts were 7.5, 4.6, and 3.0, respectively; at these time points, 19%, 3%, and 1% of subjects also met modified criteria for FM. Tender points and degree of pain diminished over time following AIM. Acutely, TPs were associated only with higher temperature (P<.001). Baseline features that predicted more TPs at 2 and 6 months were female sex, older age, less family social support, and more TPs at presentation. Neither initial laboratory tests nor psychiatric disease or distress predicted TPs. Differences between those who had and had not recovered at 6 months were found for the mean number of TPs (P<.008), the proportion of subjects with 11 or more TPs (P<.002), and the degree of pain. CONCLUSIONS: Tender points are a common, transient finding associated with AIM, but FM is an unusual long-term outcome. Demographic, social, and physical examination features predicted TPs.

Serum macrophage migration inhibition activity in patients with leprosy.

We have found that 26 of 54 (48%) untreated patients with leprosy had serum migration inhibitory activity, and that this was present in tuberculoid, borderline, and lepromatous forms of the disease. Patients with active recreational states; i.e., reversal reactions, Lucio's reaction, or erythema nodosum leprosum, were particularly apt to have this inhibitory activity. The prevalence of inhibitory activity did not vary significantly with treatment, dinitrochlorobenzene responsiveness, tuberculin responsiveness, or serum lysozyme levels.

Dinitrochlorobenzene responsivity in disseminated coccidioidomycosis: an inverse correlation with complement-fixing antibody titers.

The immunologic status of 25 patients with disseminated coccidiodomycosis was evaluated by serum anticoccidioidin complement-fixing antibody levels, coccidiodin skin tests, and dinitrochlorobenzene (DNCB) sensitization. In the 10 patients who had disseminated disease and a complement-fixing titer of 1:32 or less, responses to DNCB were similar to those of 20 controls. In the 15 patients with disseminated disease and a complement-fixing titer of 1:64 or more, responses to DNCB were statistically significantly diminished compared to controls (p = 0.002). Since the complement-fixing titer is associated with extent of dissemination, these results signify a relationship between diminished DNCB responses and extensive dissemination. Of the several hypotheses which might explain this relationship, we find the most attractive is that of a nonspecific deficiency of cell-mediated immunity developing secondarily to extensive disseminated disease.

Comparison of S-100 and OKT6 antisera in human skin.

The monoclonal antibody OKT6 and antisera against S-100 protein have both been advocated as immunologic markers of Langerhans cells in the skin. S-100 antiserum has an advantage in its ability to stain Langerhans cells in paraffin tissues. In order to evaluate whether these antibodies stain equivalent numbers of Langerhans cells in skin, we compared the staining patterns of S-100 antiserum and OKT6 antibody on biopsy specimens from 40 patients with leprosy using immunoperoxidase techniques. Utilizing OKT6 antibody, greater numbers of positive Langerhans cells were found in the epidermis in tuberculoid leprosy, reversal reaction, and erythema nodosum leprosum than in lepromatous leprosy. However, these differences were not observed with the S-100 antiserum and, overall, fewer cells were found as compared with the OKT6 antibody. In the dermis both antibodies stained "dendritic cells" that were found encircling granulomas in tuberculoid leprosy and reversal reaction. Staining in lepromatous leprosy granulomas, in contrast to the epidermal staining pattern, revealed rare OKT6-positive cells, while S-100 cells were numerous and were more diffusely distributed throughout the granuloma. Our results indicate that antiserum to S-100 protein and OKT6 antibody stain morphologically similar cells (dendritic cells), but do not provide comparable results concerning distribution and frequency of these cells.

Selective expansion of V delta 1 + T cells from leprosy skin lesions.

T cells bearing gamma delta T-cell receptors (TCRs) are prominent residents of murine epidermis and appear to be important participants in the immune response to infection in human skin. The Mitsuda reaction in leprosy, induced by intradermal challenge with Mycobacterium leprae, provides an opportunity to study the cellular events that mediate a form of delayed-type hypersensitivity (DTH) in skin. T cells bearing gamma delta TCRs comprise a significant proportion of the T-cell population in these DTH reactions. Presently we have generated T-cell lines from Mitsuda reactions in vitro and compared their TCR repertoire to that found in situ. gamma delta T cells comprised 20-40% of lines derived from these skin lesions, but < 10% of lines derived from the peripheral blood of the same individuals. Flow-cytometric analysis of variable (V) chain usage in T-cell lines derived from skin lesions indicated that V delta 1 was predominant. Evaluation of the TCR repertoire using PCR indicated that V delta 1-J delta 1 and V gamma 2-J gamma P gene rearrangements were prevalent. In comparison, V delta 2-J delta 1 gene rearrangements predominated in situ. Furthermore, nucleotide sequence analysis of the V-J junction of one T-cell line revealed limited genetic diversity of the gamma delta TCR. These findings suggest that the V delta 1 subpopulation of gamma delta T cells in Mitsuda skin reactions selectively outgrows from leprosy skin lesions in vitro. Such V delta 1 + T-cell lines should be useful for determining the relevant antigens and restriction elements in this response to a pathogen in skin.

Hair-specific keratins: characterization and expression of a mouse type I keratin gene.

A genomic clone for a member of the mouse type I hair keratin protein family has been isolated and analyzed in order to study the regulation of this keratin during the hair growth cycle. The coding sequence is divided into seven exons. The gene structure is typical of keratins in particular and intermediate filaments in general in that the intron-exon borders are not located at the domain borders of the protein. Comparison with a sheep wool keratin gene shows that the splice sites in the two hair keratin genes are found at identical locations relative to the amino acid sequence of the proteins. Similarly, comparison of the promoter areas of these genes shows several areas of nucleotide sequence conservation, including the area around the TATA box and an SV40 core enhancer sequence. In addition, a high degree of sequence identity exists in the fourth intron. In situ hybridization shows that transcripts of this gene are first found in the relatively undifferentiated proximal cortex area in the keratogenous zone of mouse vibrissae.

Identification of the genes responsive to etoposide-induced apoptosis: application of DNA chip technology.

DNA chip technology was used in an attempt to identify target genes responsible for apoptosis induced by etoposide, a p53 activating topoisomerase II inhibitor used clinically as an antitumor agent. 62 Individual mRNAs whose mass changed significantly were identified after screening oligonucleotide arrays capable of detecting 6591 unique human mRNA species. 12 (Nine induced and three repressed) of the etoposide-responsive genes were further studied by Northern analysis and an agreement rate of 92%, was reached. Among the 12 genes studied, two (WAF1/p21 and PCNA) are known p53 regulatory genes, two (glutathione peroxidase and S100A2 calcium-binding protein) appear to be the novel p53 target genes and the others appear to be p53-independent. Based upon these findings, the signalling pathways that possibly mediate etoposide-induced apoptosis are proposed.