473 research outputs found

    Heterozygosity Probabilities for Normal Relatives of Isolated Cases Affected by Incompletely Penetrant Conditions and the Calculation of Recurrence Risks for Their Offspring. I. Autosomal Dominant Genes

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    Heterozygosity probabilities P(het) for relatives of isolated cases produced by incompletely penetrant autosomal dominant genes and recurrence risks for their offspring, R = P(het).K/2, where K is the penetrance value, have been calculated in the literature for some simple particular situations. Bayes theorem and elements from the theory of finite difference equations enabled us to derive the heterozygosity probability for any individual belonging to a pedigree containing an isolated case affected with an incompletely penetrant autosomal dominant disorder. The generalized formula here derived is valid for most particular cases thus far studied in the literature. Am. J. Med. Genet. 95:43-48, 2000

    CD8 T-cell clones producing interleukin-5 and interferon-gamma in bronchial mucosa of patients with asthma induced by toluene diisocyanate

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    OBJECTIVES - The aims of the present study were to determine whether specific in vivo stimulation of asthmatics sensitized with toluene diisocyanate (TDI) induces the activation of T lymphocytes in bronchial mucosa and to characterize their phenotype and cytokine secretion profile.METHODS - Bronchial biopsies from two subjects with occupational asthma due to TDI were obtained 48 h after an asthmatic reaction induced by an inhalation challenge with TDI and after three months of no exposure to TDI, at the time when the subjects had recovered from their asthma. The fragments of bronchial mucosa were cultured in the presence of interleukin-2 so that the in vivo activated T cells present in the tissue would expand, and T blasts were then cloned under limiting dilution conditions.RESULTS - From the two 48-h specimens, 65 and 63 T-cell clones were obtained. Most of the clones exhibited the CD8 phenotype (82 and 83%). All of the CD8 clones produced interferon-gamma and 44% produced interleukin-5, but only 6% secreted interleukin-4 as well. Three months after the cessation of exposure, growing T cells could not be recovered from bronchial biopsies cultured in interleukin-2.CONCLUSIONS - The results suggest that, in sensitized subjects, exposure to TDI induces the activation of a subset of CD8 lymphocytes producing interferon-gamma and interleukin-5

    Quercetin prevents progression of disease in elastase/LPS-exposed mice by negatively regulating MMP expression

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    Abstract Background Chronic obstructive pulmonary disease (COPD) is characterized by chronic bronchitis, emphysema and irreversible airflow limitation. These changes are thought to be due to oxidative stress and an imbalance of proteases and antiproteases. Quercetin, a plant flavonoid, is a potent antioxidant and anti-inflammatory agent. We hypothesized that quercetin reduces lung inflammation and improves lung function in elastase/lipopolysaccharide (LPS)-exposed mice which show typical features of COPD, including airways inflammation, goblet cell metaplasia, and emphysema. Methods Mice treated with elastase and LPS once a week for 4 weeks were subsequently administered 0.5 mg of quercetin dihydrate or 50% propylene glycol (vehicle) by gavage for 10 days. Lungs were examined for elastance, oxidative stress, inflammation, and matrix metalloproteinase (MMP) activity. Effects of quercetin on MMP transcription and activity were examined in LPS-exposed murine macrophages. Results Quercetin-treated, elastase/LPS-exposed mice showed improved elastic recoil and decreased alveolar chord length compared to vehicle-treated controls. Quercetin-treated mice showed decreased levels of thiobarbituric acid reactive substances, a measure of lipid peroxidation caused by oxidative stress. Quercetin also reduced lung inflammation, goblet cell metaplasia, and mRNA expression of pro-inflammatory cytokines and muc5AC. Quercetin treatment decreased the expression and activity of MMP9 and MMP12 in vivo and in vitro, while increasing expression of the histone deacetylase Sirt-1 and suppressing MMP promoter H4 acetylation. Finally, co-treatment with the Sirt-1 inhibitor sirtinol blocked the effects of quercetin on the lung phenotype. Conclusions Quercetin prevents progression of emphysema in elastase/LPS-treated mice by reducing oxidative stress, lung inflammation and expression of MMP9 and MMP12.http://deepblue.lib.umich.edu/bitstream/2027.42/78260/1/1465-9921-11-131.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78260/2/1465-9921-11-131.pdfPeer Reviewe

    Heme oxygenase-1 prevents smoke induced B-cell infiltrates: a role for regulatory T cells?

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    <p>Abstract</p> <p>Background</p> <p>Smoking is the most important cause for the development of COPD. Since not all smokers develop COPD, it is obvious that other factors must be involved in disease development. We hypothesize that heme oxygenase-1 (HO-1), a protective enzyme against oxidative stress and inflammation, is insufficiently upregulated in COPD.</p> <p>The effects of HO-1 modulation on cigarette smoke induced inflammation and emphysema were tested in a smoking mouse model.</p> <p>Methods</p> <p>Mice were either exposed or sham exposed to cigarette smoke exposure for 20 weeks. Cobalt protoporphyrin or tin protoporphyrin was injected during this period to induce or inhibit HO-1 activity, respectively. Afterwards, emphysema development, levels of inflammatory cells and cytokines, and the presence of B-cell infiltrates in lung tissue were analyzed.</p> <p>Results</p> <p>Smoke exposure induced emphysema and increased the numbers of inflammatory cells and numbers of B-cell infiltrates, as well as the levels of inflammatory cytokines in lung tissue. HO-1 modulation had no effects on smoke induced emphysema development, or the increases in neutrophils and macrophages and inflammatory cytokines. Interestingly, HO-1 induction prevented the development of smoke induced B-cell infiltrates and increased the levels of CD4<sup>+</sup>CD25<sup>+ </sup>T cells and Foxp3 positive cells in the lungs. Additionally, the CD4<sup>+</sup>CD25<sup>+ </sup>T cells correlated positively with the number of Foxp3 positive cells in lung tissue, indicating that these cells were regulatory T cells.</p> <p>Conclusion</p> <p>These results support the concept that HO-1 expression influences regulatory T cells and indicates that this mechanism is involved in the suppression of smoke induced B-cell infiltrates. The translation of this interaction to human COPD should now be pursued.</p

    Waardenburg Syndrome: Clinical Differentiation Between Types I and II

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    Here we present the results of a study performed on 59 patients affected by Waardenburg syndrome (WS), 30 with the I variant, 21 having the type II, and 8 of them being isolated cases without telecanthus. These patients belong to 37 families; the main contributions and conclusions are based on the detailed study of 25 of these families, examined using standard procedures. All patients were examined as to the presence of eight cardinal signs important for the diagnosis of the condition; from each patient, from many of his/her normal relatives, and from a control sample of 300 normal individuals stratified by age and sex, 23 different craniofacial measurements were obtained. We also estimated, using our own data as well those collected from the literature, the frequencies of the cardinal signs, based on a total sample of 461 affected individuals with WSI and 121 with WSII. In order to originate discriminant functions to separate individuals affected by one of the two variants, both metric (from craniofacial measurements) as well as categoric data (based on the frequencies of the cardinal signs or symptoms) were used. Discriminant analysis based on the frequency of the eight cardinal signs can improve the separation of WSI patients without telecanthus from those presenting the variant II. We present also a Table with the conditional probabilities favoring the diagnosis of WSI for suspect subjects without telecanthus and any combination of the other seven signs/symptoms. The discriminant function based on the four ocular measurements (inner and outer intercanthal, interpupillary, and inferior lacrymal distances), on the other side, perfectly classifies patients affected by one of the variants of WS, the same taking place when the average values of the W index of all affected individuals per family are used. The discriminant function based solely in the individual W index values of patients correctly classifies 93% of WSII subjects, but only 60% of the patients with the I variant of WS. ß 2003 Wiley-Liss, Inc. KEY WORDS: Waardenburg syndrome; genetic heterogeneity; discriminant analysis INTRODUCTION The Waardenburg syndrome (WS), first comprehensively described in 1951, is a genetically heterogeneous condition, each of its forms having a wide clinical spectrum with a very high degree of phenotypic expressivity. In the present paper, we will consider only the two most frequent variants (WSI and WSII) out of the four described so far. These two forms, together accounting for a prevalence of 2 to 3 affected individuals/100,000 in the general population, are determined by non-allelic autosomal dominant mutant genes with a high penetrance. WS is characterized clinically by the association of craniofacial dysmorphim, pigmentation defects, and severe sensorineural congenital hearing impairment. The craniofacial dysmorphisms most commonly seen in affected individuals include telecanthus (in WSI only), broad and high nasal root, hypoplasia of the alae nasi, lower lacrimal dystopia, and synophrys. Telecanthus (dystopia canthorum lateroversa) is classically described as an increase of inner ocular intercantal distance (IID) with preservation of both interpupillary (IPD) and outer intercantal (OID) distances. WS patients with this sign, however, commonly present larger values of the other two measurements, so that they exhibit a certain degree of hypertelorism. Patients frequently display conspicuous pigmentary defects of the irides (totally or partially heterochromic and bright hypochromic blue irides), hypopigmented skin spots, and partial hair albinism (white forelock or early graying). The first variant (WSI), with telecanthus, is caused by mutations at the PAX3 gene located in 2q35, while the second (WSII) is determined by other non-allelic autosomal dominant mutations located in the region 3p12.3 ! 3p14.1 of the MITF gene. Many of these are point mutations involving single-base substitutions and the number of different mutations described so far for both loci is so large that the molecular screening for them in WS can not be routinely performed in most laboratories. Because of all this, the differential diagnosis between variants I and II still relies largely on classic clinical methods. Clinical signs and symptoms are similar in both conditions, but telecanthus is known to occur only in WSI; the other characteristics have contrasting frequencies in both forms, especially iris and hair pigmentary disturbances and deafness. The penetrance of the last trait is higher in the second variant of WS, which has therefore a poorer clinical prognosis. Telecanthus (sometimes hypertelorism) is the most important sign for the differentiation between both forms, because it is present in the vast majority (95-99%) of WSI patients and virtually absent in those with the WSII variant. The presence of conspicuous craniofacial dysmorphisms in WS explains why the condition has been widely studied anthropometrically. The first of these studies was performed on Waardenburg&apos;s original data by Since the penetrance of the telecanthus trait and consequently the efficiency of the W index-although generally high-are both incomplete In this paper, we describe 59 individuals affected by the Waardenburg syndromes WSI and WSII, belonging to 25 Brazilian families. A detailed craniofacial phenotypic description of all affected individuals is presented, as well as the values of several measurements taken in these patients. The relative frequencies of cardinal signs and the values of craniofacial measurements are used to compare, through discriminant analysis, WSI and WSII affected individuals. MATERIALS AND METHODS Out of the 25 families studied personally, 18 were ascertained in the Laboratory of Human Genetics (LGH, Departamento de Biologia, IB USP, São Paulo) and seven were examined at the Hospital de Reabilitação de Anomalias Cranio-Faciais (HRAC, Faculdade de Odontologia, USP, Bauru). For this, we used a standardized routine for physical examination that included the investigation, in all affected individuals (with the exception of a few instances in which one measurement could not be recorded and the corresponding feature could not be evaluated objectively), of the following eight cardinal signs and symptoms of WS: telecanthus, synophrys, iris pigmentation disturbances, localized albinism on hair (white forelock and early graying), hearing impairment, nasal root hyperplasia, hypopigmented skin spots, and lower lacrimal dystopia. We selected also, through review of the international literature, 44 different papers published from 1951 to 1995 with complete clinical presentation of cases of WS Waardenburg Syndrome 225 non-mentioned characteristic was absent, the estimate for its frequency is given by under the hypothesis (b) that the non-mentioned sign/ symptom was not investigated, its frequency estimate is given by x 00 ¼ X/(X þ Y) ¼ X/(N À Z), with expected binomial variance var(x 00 ) ¼ x 00 (1 À x 00 )/(N À Z). Obviously, the true estimate of the frequency is given by an unknown quantity within an interval with lower und upper limits given by x 0 and x 00 . If there is no additional information enabling us to choose one out of the two hypotheses above, an estimate of the true frequency x can be obtained by weighing the estimates x 0 and x 00 by the reciprocal of their expected binomial variances. This estimate will be used throughout this work to contrast the frequencies of the cardinal signs in a sample of WSI and WSII patients combining our data with those from the literature. We also determined-in random samples of Caucasian individuals stratified by sex and age (total of 300 individuals) and in affected individuals and in their relatives belonging to ten of our 25 families-23 different craniofacial measurements of interest in the diagnosis of WS. Some of these measurements were used for comparing controls and patients as well as types I and II of WS. 226 Pardono et al. We have classified as WSI all the patients, familial or isolated, that presented conspicuous telecanthus. In order to classify as WSI a case of WS without telecanthus, this affected individual should always belong to a family with at least one typical case of WSI (with telecanthus). Therefore, all cases of WSI without telecanthus presented here are familial, whereas all isolated cases of WS classified as WSI present with the sign. Inversely, all cases of WS classified as WSII are necessarily familial, that is, they belong strictly to families with at least one more affected individual, none of them presenting telecanthus. In the cases selected from literature, we applied the same classification criteria, systematically disregarding the classification of isolated cases of WS without telecanthus as being WSII. In the presentation of our cases in the Results and Discussion section, all isolated WS patients without telecanthus were grouped in a group labelled as WSII?, but their data were not used in the statistical analyses described below. For the study of cardinal characteristics, the application of the above-mentioned stringent criteria to the cases from literature enabled us to consider a total of 461 WSI patients (29 of them not presenting telecanthus) and 121 carriers of the WSII variant. With the addition of our own data to those from the literature, the discriminant analysis performed with categorical data was based, therefore, on totals of 491 WSI and 142 WSII patients, respectively. The techniques of statistical analysis used throughout this paper are detailed in standard textbooks (e.g., Zar [1999]). Those on linear and non-linear discriminant analysis in particular are detailed in Smith [1947, 1969], Penrose [1947], and Karn and Penrose [1951]. RESULTS AND DISCUSSION Description of Cases Using a modification of the genealogy symbols proposed by Discriminant Analysis Using the Frequencies of Cardinal Signs and Symptoms The estimated frequencies of the eight cardinal characteristics of WS were calculated from reliable case descriptions in the literature and are shown in Waardenburg Syndrome 227 Comparing the observed frequencies of each sign in the groups of WSI and WSII patients through chisquared tests in 2 Â 2 contingency tables, we obtained in all cases test figures that were significant at least at the 1% level. The elements necessary for performing a simplified categoric discriminant analysis, together with an application example, are summarized in Since there are only seven other possible signs besides telecanthus, all the possible combinations of these seven signs/symptoms (presence or absence) reduce to 2 7 ¼ 128. 38 out of these 128 combinations generate probability figures larger than 95% or less than 5% favoring the diagnosis of WSI and are shown in We could obtain, combining our data with those from the literature, complete individual phenotypic descriptions of 111 patients affected by WSII out of the 142 used for deriving the probabilities shown in Discriminant Analysis Based on Craniofacial Measurements First we compared the craniofacial measurements between WSI and WSII patients, and between WS patients and controls through t tests with allowance for variance heterogeneity. Using as selection criterion all variables that were statistically different between any of the two comparison groups at least at the 0.001 significance level, we chose the following variables to be used on discriminant analysis: inner intercanthal distance (IID); outer intercanthal distance (OID); interpupillary distance (IPD); lower interlacrimal distance (LID); nose interalar distance (IAD); mean length of ear (EML), obtained by averaging the longitudinal length of both auricles; and the W index (WI), a composite measure used in the literature for separating WSI and WSII patients and described in the introduction section. We decided to also include the variables facial length or morphological face height (MFH) and the mean width of ear (EMW), a measurement obtained by averaging the transversal length of both auricles. These two measurements, in spite of not showing statistical significance at the 0.001 level, exhibited differences at a critical level much less than 0.01. The statistical parameters of these nine measurements, estimated in the groups of WSI and WSII patients and controls, are shown i

    Bronchial epithelial spheroids: an alternative culture model to investigate epithelium inflammation-mediated COPD

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    <p>Abstract</p> <p>Background</p> <p>Chronic obstructive pulmonary disease (COPD) is characterized by abnormal lung inflammation that exceeds the protective response. Various culture models using epithelial cell lines or primary cells have been used to investigate the contribution of bronchial epithelium in the exaggerated inflammation of COPD. However, these models do not mimic <it>in vivo </it>situations for several reasons (e.g, transformed epithelial cells, protease-mediated dissociation of primary cells, etc.). To circumvent these concerns, we developed a new epithelial cell culture model.</p> <p>Methods</p> <p>Using non transformed non dissociated bronchial epithelium obtained by bronchial brushings from COPD and non-COPD smokers, we developed a 3-dimensional culture model, bronchial epithelial spheroids (BES). BES were analyzed by videomicroscopy, light microscopy, immunofluorescence, and transmission electron microscopy. We also compared the inflammatory responses of COPD and non-COPD BES. In our study, we chose to stimulate BES with lipopolycaccharide (LPS) and measured the release of the pro-inflammatory mediators interleukin-8 (IL-8) and leukotriene B4 (LTB4) and the anti-inflammatory mediator prostaglandin E2 (PGE2).</p> <p>Results</p> <p>BES obtained from both COPD and non-COPD patients were characterized by a polarized bronchial epithelium with tight junctions and ciliary beating, composed of basal cells, secretory cells and ciliated cells. The ciliary beat frequency of ciliated cells was not significantly different between the two groups. Of interest, BES retained their characteristic features in culture up to 8 days. BES released the inflammatory mediators IL-8, PGE2 and LTB4 constitutively and following exposure to LPS. Interestingly, LPS induced a higher release of IL-8, but not PGE2 and LTB4 in COPD BES (p < 0.001) which correlated with lung function changes.</p> <p>Conclusion</p> <p>This study provides for the first time a compelling evidence that the BES model provides an unaltered bronchial surface epithelium. More importantly, BES represent an attractive culture model to investigate the mechanisms of injuring agents that mediate epithelial cell inflammation and its contribution to COPD pathogenesis.</p

    Gender and respiratory findings in workers occupationally exposed to organic aerosols: A meta analysis of 12 cross-sectional studies

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    <p>Abstract</p> <p>Background</p> <p>Gender related differences in respiratory disease have been documented. The aim of this study was to investigate gender related differences in respiratory findings by occupation. We analyzed data from 12 of our previously published studies.</p> <p>Methods</p> <p>Three thousand and eleven (3011) workers employed in "organic dust" industries (1379 female and 1632 male) were studied. A control group of 806 workers not exposed to any kind of dust were also investigated (male = 419, female = 387). Acute and chronic respiratory symptoms and lung function were measured. The weighted average method and the Mantel-Haentszel method were used to calculate the odds ratios of symptoms. Hedge's unbiased estimations were used to measure lung function differences between men and women.</p> <p>Results</p> <p>There were high prevalences of acute and chronic respiratory symptoms in all the "dusty" studied groups compared to controls. Significantly less chronic cough, chronic phlegm as well as chronic bronchitis were found among women than among men after the adjustments for smoking, age and duration of employment. Upper respiratory tract symptoms by contrast were more frequent in women than in men in these groups. Significant gender related lung function differences occurred in the textile industry but not in the food processing industry or among farmers.</p> <p>Conclusion</p> <p>The results of this study suggest that in industries processing organic compounds there are gender differences in respiratory symptoms and lung function in exposed workers. Whether these findings represent true physiologic gender differences, gender specific workplace exposures or other undefined gender variables not defined in this study cannot be determined. These data do not suggest that special limitations for women are warranted for respiratory health reasons in these industries, but the issue of upper respiratory irritation and disease warrants further study.</p

    Influence of genetic factors on toluene diisocyanate-related symptoms: evidence from a cross-sectional study

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    Background: Toluene diisocyanate (TDI) is a highly reactive compound used in the production of, e. g., polyurethane foams and paints. TDI is known to cause respiratory symptoms and diseases. Because TDI causes symptoms in only a fraction of exposed workers, genetic factors may play a key role in disease susceptibility. Methods: Workers (N = 132) exposed to TDI and a non-exposed group ( N = 114) were analyzed for genotype (metabolising genes: CYP1A1*2A, CYP1A1*2B, GSTM1*O, GSTM3*B, GSTP1 1105V, GSTP1 A114V, GSTT1*O, MPO -463, NAT1*3, *4, *10, *11, *14, *15, NAT2*5, *6, *7, SULT1A1 R213H; immune-related genes: CCL5 -403, HLA-DQB1* 05, TNF-308, TNF-863) and symptoms of the eyes, upper and lower airways ( based on structured interviews). Results: For three polymorphisms: CYP1A1*2A, CYP1A1*2B, and TNF -308 there was a pattern consistent with interaction between genotype and TDI exposure status for the majority of symptoms investigated, although it did reach statistical significance only for some symptoms: among TDI-exposed workers, the CYP1A1 variant carriers had increased risk (CYP1A1*2A and eye symptoms: variant carriers OR 2.0 95% CI 0.68-6.1, p-value for interaction 0.048; CYP1A1*2B and wheeze: IV carriers OR = 12, 1.4-110, p-value for interaction 0.057). TDI-exposed individuals with TNF-308 A were protected against the majority of symptoms, but it did not reach statistical significance. In the non-exposed group, however, TNF -308 A carriers showed higher risk of the majority of symptoms ( eye symptoms: variant carriers OR = 2.8, 1.1-7.1, p-value for interaction 0.12; dry cough OR = 2.2, 0.69-7.2, p-value for interaction 0.036). Individuals with SULT1A1 213H had reduced risk both in the exposed and non-exposed groups. Other polymorphisms, showed associations to certain symptoms: among TDI-exposed, NAT1*10 carriers had a higher risk of eye symptoms and CCL5 -403 AG+AA as well as HLA-DQB1 *05 carriers displayed increased risk of symptoms of the lower airways. GSTM1, GSTM3 and GSTP1 only displayed effects on symptoms of the lower airways in the non-exposed group. Conclusion: Specific gene-TDI interactions for symptoms of the eyes and lower airways appear to exist. The results suggest different mechanisms for TDI- and non- TDI-related symptoms of the eyes and lower airways
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