Genetic profiles of transcriptomic clusters of childhood asthma determine specific severe subtype.

BACKGROUND: Previous studies have defined transcriptomic subtypes of adult asthma using samples of induced sputum and bronchial epithelium; however, those procedures are not readily applicable in the clinic, especially for childhood asthma. OBJECTIVE: We aim to dissect the transcriptomic clusters of childhood asthma using highly variably expressed genes of peripheral blood mononuclear cells (PBMC) among patients. METHODS: Gene expression of PBMC from 133 asthmatic children and 11 healthy controls was measured with Illumina microarrays. We applied the k-means clustering algorithm of 2048 genes to assign asthmatic children into clusters. Genes with differential expression between asthma clusters and healthy controls were used to investigate whether they could identify severe asthma of children and adults. RESULTS: We identified 3 asthma clusters with distinct inflammatory profiles in peripheral blood. Cluster 1 had the highest eosinophil count. Cluster 2 showed lower counts of both eosinophils and neutrophils. Cluster 3 had the highest neutrophil count and the poorest treatment control. Compared with other patients, Cluster 3 exhibited a unique gene expression pattern which was associated with changes in the glucocorticoid signalling and activation of the T helper 1/T helper 17 (TH 1/TH 17) immune pathways. In the validation studies, an 84-gene signature could identify severe asthma in children on leucocytes, as well as severe asthma in adults on CD8+ T cells. CONCLUSIONS AND CLINICAL RELEVANCE: Gene expression profiling of PBMC is useful for the identification of TH 1/TH 17-mediated asthma with poor treatment control. PBMC and CD8+ T cells could be important targets for the investigation and identification of severe asthma.

Childhood asthma clusters reveal neutrophil-predominant phenotype with distinct gene expression.

BACKGROUND: Childhood asthma comprises different phenotypes with complex pathophysiology. Different asthma phenotypes evoke various clinical symptoms and vary in their responses to treatments. METHODS: We applied k-means clustering algorithm of twelve objective laboratory tests among 351 asthmatic children enrolled in the Taiwanese Consortium of Childhood Asthma Study (TCCAS). We constructed gene expression profiles of peripheral blood mononuclear cells (PBMC) from children with different asthma phenotypes. RESULTS: Five distinct phenotypes of childhood asthma were identified and can be characterized by either eosinophil-predominant or neutrophil-predominant inflammatory characteristics. In the gene expression profile analysis, significant differences were noted for neutrophil-predominant asthma, compared with samples from all the other asthma phenotypes. The vast majority of the differentially expressed genes in neutrophil-predominant asthma was associated with corticosteroid response. From an independent inhaled corticosteroid (ICS) response cohort, we also found neutrophils could be activated in this severe asthma phenotype and neutrophil-predominant asthma may be associated with corticosteroid nonresponsiveness. CONCLUSION: Phenotype clustering of childhood asthma can be helpful to identify clinically relevant patients and reveal different inflammatory characteristics in asthmatic children. Neutrophil-predominant asthma is the most severe asthma phenotype with poor corticosteroid response. Gene expression profile of different asthma phenotypes not only improve our knowledge of childhood asthma, but also can guide asthma precision medicine.

Trends of mortality and causes of death among HIV-infected patients in Taiwan, 1984-2005.

BACKGROUND: The aim of this study was to analyse the trends of mortality and causes of death among HIV-infected patients in Taiwan from 1984 to 2005. METHODS: Registered data and death certificates for HIV-infected patients from Taiwan Centers for Disease Control were reviewed. Mortality rate and causes of deaths were compared among patients whose HIV diagnosis was made in three different study periods: before the introduction of highly active antiretroviral therapy (HAART) (pre-HAART: from 1 January 1984 to 31 March 1997), in the early HAART period (from 1 April 1997 to 31 December 2001), and in the late HAART period (from 1 January 2002 to 31 December 2005). A subgroup of 1161 HIV-infected patients (11.4%) followed at a university hospital were analysed to investigate the trends of and risk factors for mortality. RESULTS: For 10 162 HIV-infected patients with a mean follow-up of 1.97 years, the mortality rate of HIV-infected patients declined from 10.2 deaths per 100 person-years (PY) in the pre-HAART period to 6.5 deaths and 3.7 deaths per 100 PY in the early and late HAART periods, respectively (P<0.0001). For the 1161 patients followed at a university hospital (66.8% with CD4 count <200 cells/microL), HAART reduced mortality by 89% in multivariate analysis, and the adjusted hazard ratio for death was 0.28 (95% confidence interval 0.24, 0.33) in patients enrolled in the late HAART period compared with those in the pre-HAART period. Seventy-six per cent of the deaths in the pre-HAART period were attributable to AIDS-defining conditions, compared with 36% in the late HAART period (P<0.0001). The leading causes of non-AIDS-related deaths were sepsis (14.7%) and accidental death (8.3%), both of which increased significantly throughout the three study periods. Compared with patients acquiring HIV infection through sexual contact, injecting drug users were more likely to die from non-AIDS-related causes. CONCLUSIONS: The mortality of HIV-infected patients declined significantly after the introduction of HAART in Taiwan. In the HAART era, AIDS-related deaths decreased significantly while deaths from non-AIDS-related conditions increased.

Bax, Bak and mitochondrial oxidants are involved in hypoxia-reoxygenation-induced apoptosis in human placenta.

Although apoptosis is prominent in placental cells in pregnancy complications such as preeclampsia, the cause is unknown. We surmised that hypoxia-reoxygenation (HR) is the mechanism and hypothesized that mitochondrial oxidants and Bcl-2 proteins cause HR-induced placental apoptosis. Our goal was studying expression of five Bcl-2 proteins--Bcl-2, Bcl-xL, Bax, Bak, Bad--and testing effects of diazoxide and cyclosporine A on oxidative stress and apoptosis in villous tissues subjected to HR. Term human placentas were obtained from normal pregnancies following elective caesarean deliveries. Villous tissues were subjected to "repetitive HR" (one hour at 2% O(2) then one hour at 8% O(2), alternatively, for a total of 6h) or "prolonged HR" (3h at 2% O(2) then 3h of 8% O(2)). Samples maintained at 2% and 8% O(2) served as hypoxic and normoxic controls, respectively. Prolonged HR caused the most severe villous apoptotic changes, increased the expression of Bax and Bak mRNA and protein and reduced the expression of Bcl-2 mRNA. Pre-administration of diazoxide and cyclosporine A reduced TUNEL-positive nuclei and levels of nitrotyrosine and 4-hydroxy-2-nonenol after prolonged HR. Thus, duration of hypoxia and reoxygenation is important in determining severity of HR-induced apoptosis in placenta. These apoptotic changes are closely associated with Bax and Bak effects and oxidative stress in mitochondria.

Characterisation of plasmids encoding CTX-M-3 extended-spectrum beta-lactamase from Enterobacteriaceae isolated at a university hospital in Taiwan.

CTX-M-3 is the most common extended-spectrum beta-lactamase produced by Enterobacteriaceae in Taiwan. The present study was conducted to characterise the genetic environment surrounding bla(CTX-M-3). A total of 11 ceftriaxone-resistant isolates were studied: Escherichia coli (n=4), Klebsiella pneumoniae (n=5) and Salmonella enterica serotypes Anatum (SA831R) and Potsdam (SC72). Molecular methods used included polymerase chain reaction, sequencing, DNA-DNA hybridisation, conjugation, physical mapping and restriction fragment length polymorphism (RFLP) analysis. All isolates examined carried bla(CTX-M-3) on large plasmids (>70kb). The resistance plasmids of the two Salmonella and two K. pneumoniae strains (KP104 and KP116) were confirmed to be conjugative in vitro. RFLP analysis indicated that the plasmids were different. Physical mapping also revealed the difference between the two Salmonella plasmids, pSA831R (82kb) and pSC72 (74kb). An insertion sequence, ISEcp1, was found upstream of each bla(CTX-M-3) gene. However, sequencing of downstream regions of the bla genes showed two different patterns: the presence of orf477 in pSA831R and of orf1-mucA in pSC72, pKP104 and pKP116. IncI1-type oriT and nikA sequences were present in the plasmids of all the clinical isolates tested, except S. Anatum. Different bla(CTX-M-3)-carrying plasmids were identified among the enterobacteria studied. The presence of ISEcp1 in all isolates may be associated with the widespread resistance among Enterobacteriaceae. Although the plasmids were not identical, they appeared to belong to the same incompatibility group (IncI1-like plasmids), suggesting that they are genetically related but may have evolved divergently over time.

Interleukin-1 modulates phosphorylation of proteins in human osteoblastic cells.

Interleukin-1 (IL-1) is a potent bone resorbing cytokine with diverse biological effects. We previously reported that IL-1 inhibits PDGF-AA-induced biological activities including PDGF-AA-induced tyrosyl phosphorylation. In the present studies, we first investigated and compared the tyrosyl phosphorylation pattern induced by EGF, IGF-1, PDGF-AA, and bFGF in human osteoblastic cells. We then examined the effect of IL-1 on the tyrosyl phosphoproteins induced by each ligand. Immunoblot analyses show that EGF, IGF-1, and PDGF-AA each elicit a different pattern of tyrosyl phosphorylated proteins in normal human osteoblastic cells. IL-1 beta inhibits PDGF-AA induced autophosphorylation by down-regulation of the PDGF-alpha receptor, as demonstrated by immunoprecipitation experiments. For other ligand-induced tyrosyl phosphoproteins, IL-1 beta reduced the intensity of EGF-induced pp55,000, and IGF-1 induced pp185,000 and pp175,000. These experiments indicate that IL-1 inhibits phosphorylation of specific proteins induced by growth factors. By using inhibitors of secondary message pathways, we determined that the inhibitory effect of IL-1 beta on PDGF-AA receptor binding and receptor tyrosyl autophosphorylation was not dependent on protein kinase A, protein kinase C, or the formation of prostaglandins. These data suggest the existence of an alternative pathway that may participate in IL-1 beta signaling.

Temporal summation in dark-adapted 10-week old infants.

The effect of stimulus duration on the b-wave and psychophysical responses of dark-adapted 10-week-old infants and adult control subjects is reported. Both infant and adult b-wave sensitivities vary with stimulus duration, show summation for brief duration stimuli, critical durations estimated at 88-155 msec, and little variation in sensitivity for longer durations. There are however, substantial differences between the infant and adult psychophysical temporal summation functions. The infant function is described by a straight line, slope about -0.5, across all flash durations while adults show summation at durations less than 100 msec and critical durations of 136 to 151 msec. Adult, but not infant, b-wave integration times and b-wave rise and fall times show duration-dependent changes. Thus, both ERG and psychophysical measures demonstrate immaturities in the rod mediated function of the infant retina.

Analysis of the secular trend and seasonal variation of measles mortality rate in Taiwan.

The secular trend and seasonal variation of measles mortality rate in Taiwan from 1959 to 1981 were analyzed through multiple regression analyses. A significant downward trend with a regular two-year cyclic fluctuation was observed before and after the implementation of a mass vaccination campaign, and the difference between odd and even years was greater in later years than in earlier years. There was a characteristic unimodal pattern of seasonal variation which peaked in the months of late spring or early summer, and measles deaths were found more clustered in epidemic years than in nonepidemic years. While 94.3% of the total variation of annual measles mortality rate could be explained by calendar year, two-year cycle, and their interaction; 87.6% of the total variation of monthly measles mortality rate could be explained by calendar year, two-year cycle, month, and the interaction between two-year cycle and month. The implication and application of such multiple regression analysis of temporal components of measles epidemiology are discussed.

ANG II promotes IGF-IIR expression and cardiomyocyte apoptosis by inhibiting HSF1 via JNK activation and SIRT1 degradation.

Hypertension-induced cardiac hypertrophy and apoptosis are major characteristics of early-stage heart failure. Our previous studies found that the activation of insulin-like growth factor receptor II (IGF-IIR) signaling was critical for hypertensive angiotensin II (ANG II)-induced cardiomyocyte apoptosis. However, the detailed mechanism by which ANG II regulates IGF-IIR in heart cells remains elusive. In this study, we found that ANG II activated its downstream kinase JNK to increase IGF-IIR expression through the ANG II receptor angiotensin type 1 receptor. JNK activation subsequently led to sirtuin 1 (SIRT1) degradation via the proteasome, thus preventing SIRT1 from deacetylating heat-shock transcription factor 1 (HSF1). The resulting increase in the acetylation of HSF1 impaired its ability to bind to the IGF-IIR promoter region (nt -748 to -585). HSF1 protected cardiomyocytes by acting as a repressor of IGF-IIR gene expression, and ANG II diminished this HSF1-mediated repression through enhanced acetylation, thus activating the IGF-IIR apoptosis pathway. Taken together, these results suggest that HSF1 represses IGF-IIR gene expression to protect cardiomyocytes. ANG II activates JNK to degrade SIRT1, resulting in HSF1 acetylation, which induces IGF-IIR expression and eventually results in cardiac hypertrophy and apoptosis. HSF1 could be a valuable target for developing treatments for cardiac diseases in hypertensive patients.

Myeloperoxidase in the plasma and placenta of normal pregnant women and women with pregnancies complicated by preeclampsia and intrauterine growth restriction.

Myeloperoxidase (MPO) is a heme protein produced and released by activated neutrophils and monocytes, and increased MPO is considered important in the pathophysiology of cardiovascular diseases (CVD). Accumulating evidence suggests that preeclampsia (PE), idiopathic intrauterine growth restriction (IUGR), and CVD share many similar metabolic disturbances, including an enhanced systemic inflammatory response and endothelial dysfunction. We hypothesized that MPO plays an important role in the development of PE and IUGR. Plasma samples were collected mid-gestation and at delivery from women with normal pregnancies (n = 40) and those who subsequently developed PE (n = 20), IUGR (n = 11) or both (PE + IUGR, n = 8). Placental samples were obtained immediately after delivery from 22 women with normal pregnancies, 19 women with PE, 14 women with IUGR, and 14 women with PE + IUGR. The MPO concentrations were measured using ELISA. Women with PE + IUGR had significantly higher plasma MPO before delivery than normal pregnant women. There was no difference in plasma levels at mid-gestation or the placental concentrations between women with normal pregnancies and those who developed PE, IUGR, or PE + IUGR. Using explants prepared from the placentas of 8 women with normal pregnancies and 8 women with PE, we found no difference in the levels of MPO in the tissue homogenates and culture media between these two groups of women. Together, these results indicate that increased maternal circulating MPO in women with PE + IUGR is likely a result of enhanced systemic inflammation caused by the established disease rather than a primary pathophysiological factor.

An atomic force microscope study of thermal behavior of phospholipid monolayers on mica.

We observed by using atomic force microscope (AFM) phospholipid (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) monolayers on mica being annealed and cooled to a selection of temperatures through steps of 2-4 degrees C/min. The annealed phospholipid monolayers started to disappear at 45-50 degrees C and disappeared completely above 60-63 degrees C under AFM observation. The phospholipid monolayers reformed when the samples were cooled below 60 degrees C and developed from fractal into compact monolayer films with decreasing temperatures. Simultaneously the height of the reformed phospholipid films also increased with decreasing temperatures from 0.4 nm to the value before annealing. The observed thermal features are attributed to a phase-transition process that upon heating to above 45-50 degrees C, the lipids condensed in the monolayers transform into a low-density expanded phase in which the lipids are invisible to AFM, and the transformation continues and completes at 60-63 degrees C. The lipid densities of the expanded phase inferred from the dissociated area of the condensed phase are observed to be a function of the temperature. The behavior contrasts with a conventional first-order phase transition commonly seen in the Langmuir films. The temperature-dependent height and shape of the reformed phospholipid films during cooling are argued to arise from the adjustment of the packing and molecular tilting (with respect to the mica surface) of the phospholipids in order to accommodate more condensed phospholipids.

Risk factors of alcoholism among Taiwan aborigines: implications for etiological models and the nosology of alcoholism.

The objective of this study was to explore possible risk factors of alcohol abuse (AA) and dependence (AD), as defined by DSM-III criteria, in Taiwan aborigines. The risk factors in a sample of 1555 Taiwan aborigines were analyzed by using the chi-square test and multivariate logistic regression statistics. The logistic regression showed that the risk factors of AD are being male, having relatively little education, being involved in a problem marriage, being a laborer, being part of a couple with a drinking problem, and having a positive family history of alcoholism. AA has the risk factors of ethnic subgroups dwelling in the main Taiwan Island, male, poor education, working people, and a drinking problem for the couple. Etiological models are proposed as social origins for AA, with interactional model for AD, in this aboriginal sample. Data on Chinese alcoholism is discussed, and a generalized hypothesis constructed that, for the same phenotypical subtype of alcoholism in different ethnic groups, the etiological models are different.

Risk factors of alcoholism in Taiwan Chinese: an epidemiological approach.

This study investigated the risk factors of alcohol abuse and alcohol dependence, as defined by DSM-III criteria, in 11,004 Chinese subjects in the Taiwan community. Risk factors were analyzed using chi-square and multivariate logistic regression statistics. The logistic regression shows that the risk factors of alcohol dependence include male, having had childhood or adulthood behavior problems; of alcohol abuse include male, having had childhood or adulthood behavior problems, non-metropolitan community, age cohort, job-holder. The etiological models proposed are biological for Chinese alcohol dependence and interactional for Chinese alcohol abuse.

Alcoholism by Chinese diagnostic interview schedule: a prevalence and validity study.

A community survey in metropolitan Taipei (MT) and two small towns (ST) by using the Chinese modified diagnostic interview schedule (DIS-CM) revealed a significant difference in the prevalence of alcohol abuse (AA) defined by DSM-III between two study samples (MT 3.4%; ST 8.0%), but the prevalence of alcohol dependence (AD) was not different (MT 1.5%; ST 1.8%). These figures are significantly higher than that of an earlier Formosan study. Demographic data, psychiatric symptoms, medical complications and impairment of social functions were adopted as the variables to validate the nosological status of AA and AD. The results of this study substantiated that AA and AD identified by the DIS-CM were nosologically different from a non-alcoholic group. The possible reasons for an increasing prevalence of alcoholism in Taiwan Chinese were discussed. An etiological hypothesis was proposed for AA and AD on account of their differential prevalences.

Chinese diagnostic interview schedule. II. A validity study on estimation of lifetime prevalence.

The validity of DIS-CM (Chinese modified version of Diagnostic Interview Schedule) was examined by analyzing lifetime prevalence of each age group, age at onset, and recency of illness. The magnitude of the discrepancy between the empirical and the estimated data was adopted as the criterion of the degree of deviation. Manic and depressive episodes were found to be seriously underestimated. Schizophrenic, panic, phobic and antisocial personality disorders were probably underestimated. The observed lifetime prevalence figures with DIS-CM are rather conservative for these disorders. The prevalence data of a recent 1-year period are less biased and more reliable. The nature of the disease, recall effect, active or passive psychological resistance, mortality, and uncooperative attitude are considered factors that induce an underestimate of lifetime prevalence.

Alcoholism among Taiwan aborigines defined by the Chinese Diagnostic Interview Schedule: a comparison with alcoholism among Chinese.

The prevalence of alcoholism was reported to be 0.1% in an aboriginal study on Taiwan using the census survey method in the 1950s. This study adopted a modified Chinese Diagnostic Interview Schedule to determine the prevalence of DSM-III-defined alcohol abuse (AA) and alcohol dependence (AD) in the Atayal, Paiwan and Yami ethnic groups of Taiwan aborigines. Stratified random sampling was used. The sample sizes of Atayal, Paiwan and Yami were 793, 656 and 106 respectively. The prevalence rates of DSM-III-defined AA and AD were 11.6%, 11.4% and 14.2%; and 9.0%, 8.1% and 6.4% respectively. No significant difference was found between the 3 ethnic groups. These prevalence figures are significantly higher than those for Chinese. In this comparative analysis, 2 distinct etiological hypotheses are proposed for the AA and the AD.

IL-1 and transforming growth factor-beta inhibit platelet-derived growth factor-AA binding to osteoblastic cells by reducing platelet-derived growth factor-alpha receptor expression.

Platelet-derived growth factor (PDGF) is thought to play a significant role in bone repair and regeneration. We previously demonstrated that PDGF-AA-induced chemotaxis and proliferation can be modulated by IL-1. We now report that IL-1 and transforming growth factor-beta (TGF-beta) significantly decrease the number of PDGF-AA binding sites in both normal and tumor-derived human osteoblastic cells, whereas PDGF-BB binding is minimally affected. The affinity of PDGF-AA binding remains unchanged in the presence of IL-1, but is slightly reduced by TGF-beta as demonstrated by Scatchard analysis. We also showed that tyrosyl kinase phosphorylation after PDGF-AA binding is decreased in the presence of both IL-1 and TGF-beta. Northern blot analysis indicates that both IL-1 and TGF-beta decrease the expression of PDGF-alpha receptor mRNA. These results suggest that IL-1 and TGF-beta have the potential to regulate PDGF-AA-induced biologic activity in normal human osteoblastic cells and in human osteoblastic sarcoma cells by decreasing the levels of the PDGF-alpha receptor.