Rationale: Several family-based studies have identified genetic linkage for lung function and airflow obstruction to chromosome 2q.
Objectives: We hypothesized that merging results of high-resolution single nucleotide polymorphism (SNP) mapping in four separate populations would lead to the identification of chronic obstructive pulmonary disease (COPD) susceptibility genes on chromosome 2q.
Methods: Within the chromosome 2q linkage region, 2,843 SNPs were genotyped in 806 COPD cases and 779 control subjects from Norway, and 2,484 SNPs were genotyped in 309 patients with severe COPD from the National Emphysema Treatment Trial and 330 community control subjects.
Sulphonation of small molecules by cytosolic sulphotransferases in mammals is an important process in which endogenous molecules are modified for inactivation/activation of their biological effects. Plants possess large numbers of sulphotransferase genes, but their biological functions are largely unknown. Here, we present a functional analysis of the Arabidopsis sulphotransferase AtSOT12 (At2g03760).
View Article and Find Full Text PDFObjective: To determine whether strategies to counsel and empower patients with heartburn-predominant dyspepsia could improve health-related quality of life.
Methods: Using a cluster randomized, parallel group, multicentre design, nine centres were assigned to provide either basic or comprehensive counselling to patients (age range 18 to 50 years) presenting with heartburn-predominant upper gastrointestinal symptoms, who would be considered for drug therapy without further investigation. Patients were treated for four weeks with esomeprazole 40 mg once daily, followed by six months of treatment that was at the physician's discretion.
Can J Gastroenterol
January 2010
Long wait times for health care have become a significant issue in Canada. As part of the Canadian Association of Gastroenterology's Human Resource initiative, a questionnaire was developed to survey patients regarding wait times for initial gastroenterology consultation and its impact. A total of 916 patients in six cities from across Canada completed the questionnaire at the time of initial consultation.
View Article and Find Full Text PDFTo achieve gas exchange, inspired air must pass through an intricate and dynamic tracheobronchial tree. The tree offers resistance to airflow, and increased resistance is the most important functional change in lung disease. Numerous mechanisms contribute to increased resistance by causing airway narrowing, closure, occlusion, and/or obliteration.
View Article and Find Full Text PDFRationale: Damage to airway epithelium is followed by deposition of extracellular matrix (ECM) and migration of adjacent epithelial cells. We have shown that epithelial cells from children with asthma fail to heal a wound in vitro.
Objectives: To determine whether dysregulated ECM production by the epithelium plays a role in aberrant repair in asthma.
The aims of this article are to summarize existing knowledge regarding the pathophysiology of small airways disease in cystic fibrosis (CF), to speculate about additional mechanisms that might play a role, and to consider the available or potential options to treat it. In the first section, we review the evidence provided by pathologic, physiologic, and imaging studies suggesting that obstruction of small airways begins early in life and is progressive. In the second section we discuss how the relationships between CF transmembrane conductance regulator (CFTR), ion transport, the volume of the periciliary liquid layer and airway mucus might lead to defective mucociliary clearance in small airways.
View Article and Find Full Text PDFRationale: The airflow limitation that defines severity of chronic obstructive pulmonary disease (COPD) is caused by a combination of small airway obstruction and emphysematous lung destruction.
Objectives: To examine the hypothesis that small airway obstructive and emphysematous destructive lesions are produced by differential expression of genes associated with tissue repair.
Methods: The expression of 54 genes associated with repair of repetitively damaged tissue was measured in 136 paired samples of small bronchioles and surrounding lung tissue separated by laser capture microdissection.
Am J Physiol Lung Cell Mol Physiol
March 2010
The amplitude of strain in airway smooth muscle (ASM) produced by oscillatory perturbations such as tidal breathing or deep inspiration (DI) influences the force loss in the muscle and is therefore a key determinant of the bronchoprotective and bronchodilatory effects of these breathing maneuvers. The stiffness of unstimulated ASM (passive stiffness) directly influences the amplitude of strain. The nature of the passive stiffness is, however, not clear.
View Article and Find Full Text PDFBackground: Although the accepted paradigm is that the proteins stored in eosinophil crystalloid granules are translated from messenger RNA transcribed in the cell nucleus, recent ultrastructural evidence suggests that protein synthesis may also take place within eosinophilic granules.
Methods: We used 2 different methods to detect the presence of DNA and RNA in eosinophil secretory granules. Using bromodeoxyuridine, a thymidine analogue, and bromouridine, a uracil analogue, we labeled the DNA and RNA in eosinophils in vivo in rabbits.
Airway smooth muscle (ASM) plays a vital role in the exaggerated airway narrowing seen in asthma. However, whether asthmatic ASM is mechanically different from nonasthmatic ASM is unclear. Much of our current understanding about ASM mechanics comes from measurements made in other species.
View Article and Find Full Text PDFVolatile emissions from the commercial growth promoting soil bacterium Bacillus subtilis (GB03) are effective in augmenting short-term growth, photosynthetic capacity and salt tolerance in Petri-dish grown Arabidopsis seedlings. In contrast, the impact sustained GB03 volatile exposure on plant growth and development has yet to be examined. Here is provided physical and physiological data establishing that bacterial volatiles induce long-term growth promotion, elevated photosynthetic capacity and iron accumulation, as well as delayed albeit higher seed count compared with water-treated control plants.
View Article and Find Full Text PDFChronic obstructive pulmonary disease (COPD) fulfills criteria for a complex genetic disease in which environmental factors interact with multiple polymorphic genes to influence susceptibility. Finding the genes that influence susceptibility can be approached in hypothesis testing or unbiased study designs. In candidate gene association studies, genetic variation in, and/or levels of, expression of genes known or suspected to be involved in the pathogenesis of COPD are compared in affected and unaffected individuals.
View Article and Find Full Text PDFBackground: A study was undertaken to determine if quantitative CT estimates of lung parenchymal overinflation and airway dimensions in smokers with a normal forced expiratory volume in 1 s (FEV(1)) can predict the rapid decline in FEV(1) that leads to chronic obstructive pulmonary disease (COPD).
Methods: Study participants (n = 143; age 45-72 years; 54% male) were part of a lung cancer screening trial, had a smoking history of >30 pack years and a normal FEV(1) and FEV(1)/forced vital capacity (FVC) at baseline (mean (SD) FEV(1) 99.4 (12.
Chemical investigations of aerial parts of Tephrosia purpurea yielded the rare prenylated flavonoids, tephropurpulin A (1) and isoglabratephrin (2), in addition to a previously identified flavonoid, glabratephrin (3). Structures were established by 1D and 2D NMR spectroscopy, as well as by HR-MS analysis; for compounds 2 and 3, structures were confirmed by X-ray analysis.
View Article and Find Full Text PDFCystic fibrosis (CF) is a monogenic disease due to mutations in the CFTR gene. Yet, variability in CF disease presentation is presumed to be affected by modifier genes, such as those recently demonstrated for the pulmonary aspect. Here, we conduct a modifier gene study for meconium ileus (MI), an intestinal obstruction that occurs in 16-20% of CF newborns, providing linkage and association results from large family and case-control samples.
View Article and Find Full Text PDFBackground: The authors of previous reports have suggested that women are more susceptible to cigarette smoke and to an airway-predominant COPD phenotype rather than an emphysema-predominant COPD phenotype. The purpose of this study was to test for sex differences in COPD phenotypes by using high-resolution CT (HRCT) scanning in male and female smokers with and without COPD.
Methods: All subjects completed spirometry and answered an epidemiologic respiratory questionnaire.
Background: T-cell immunoglobulin mucin-3 (TIM3) is a TH1-specific type 1 membrane protein that regulates TH1 proliferation and the development of immunological tolerance. TIM3 and its genetic variants have been suggested to play a role in regulating allergic diseases. Polymorphisms in the TIM3 promoter region have been reported to be associated with allergic phenotypes in several populations.
View Article and Find Full Text PDFObjectives: Phenotype characteristics of inflammatory bowel disease (IBD) may differ significantly among ethnic subpopulations. The aim of this study was to characterize the IBD phenotype in French Canadians, the most prominent founder population in North America.
Methods: Using well-characterized phenotype data in the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)-IBD Genetics Consortium repository on patients with IBD, we compared phenotypic characteristics of 202 French Canadians with those of 1,287 other Caucasian patients.
Background: Latent adenoviral infection may amplify cigarette smoke-induced lung inflammation and therefore play an important role in the development of chronic obstructive pulmonary disease (COPD). Adenoviruses can evade the human immune response via their 19-kDa protein (19K) which delays the expression of class I human leukocyte antigen (HLA) proteins. The 19K protein shows higher affinity to HLA-B7 and A2 compared with HLA-A1 and A3.
View Article and Find Full Text PDFAirway smooth muscle (ASM) in individuals with asthma is continuously stimulated by spasmogens released as part of chronic airway inflammation. This chronic submaximal stimulation of ASM produces "tone," which may or may not narrow airways sufficiently to induce respiratory symptoms. However, when coupled with a bronchoprovocative challenge with a nonspecific contractile agonist, this increased tone could contribute to the manifestation of airway hyperresponsiveness (AHR).
View Article and Find Full Text PDFThis is a description of the Study of Asthma, Genes and the Environment (SAGE), a novel birth cohort created from provincial healthcare administrative records. It is a general population-based cohort, composed of children at high and low risk for asthma, living in urban and rural environments in Manitoba, Canada. The SAGE study captures the complete longitudinal healthcare records of children born in 1995 and contains detailed information on early-life exposures, such as antibiotic utilization and immunization, in relationship to the development of asthma.
View Article and Find Full Text PDFStress and strain are omnipresent in the lung due to constant lung volume fluctuation associated with respiration, and they modulate the phenotype and function of all cells residing in the airways including the airway smooth muscle (ASM) cell. There is ample evidence that the ASM cell is very sensitive to its physical environment, and can alter its structure and/or function accordingly, resulting in either desired or undesired consequences. The forces that are either conferred to the ASM cell due to external stretching or generated inside the cell must be borne and transmitted inside the cytoskeleton (CSK).
View Article and Find Full Text PDFBackground: Interleukin-6 (IL6) is a pleiotropic pro-inflammatory and immunomodulatory cytokine which probably plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). There is a functional single nucleotide polymorphism (SNP), -174G/C, in the promoter region of IL6. It was hypothesised that IL6 SNPs influence susceptibility for impaired lung function and COPD in smokers.
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