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1.
Nitric oxide (NO) is a free radical produced by several lung cells via the enzyme nitric oxide synthetase (NOS) and can be easily measured in exhaled air by chemiluminescence analysis. As the iso-enzyme iNOS may be induced by cytokines and endotoxin, NO is elevated in several chronic inflammatory airway diseases. Prior to using exhaled nitric oxide (eNO) as a non-invasive marker of airway inflammation in daily routine, the role of possibly influencing factors such as age, time of the day, smoking exposure and intra-individual variability have to be clarified. NO concentrations were measured in 107 healthy children aged 4–18 years at an expiratory flow of 184 ml/s. Spirometry and a skin-prick test were performed and a questionnaire on family history of atopy, personal symptoms of atopic disease and smoke exposure was completed. For intra-individual variability nitric oxide was measured in six children three times daily on 6 consecutive days. Median eNO concentration was 5.7 p.p.b., and increased significantly with age but did not vary with gender. No correlation was found between eNO and smoke exposure, positive skin-prick test, FEV 1, MEF25 and time of the day. There was no circadian rhythm found in the six children measured on 6 consecutive days, but the eNO showed an intra-individual coefficient of variation of 25.9%. With the help of a two-compartment model of the lung the alveolar NO concentration was estimated to be 4.1 p.p.b and was shown to be constant with age, whereas the airway part of NO steadily increased with age. When comparing eNO values with standardized measurement techniques, the age of the children and the large intra-subject coefficient of variation have to be taken into account, whereas in healthy children subject-specific factors such as atopic history, gender and skin test reactivity did not affect eNO measurement.  相似文献   
2.
1. The effect of cibacron blue, a selective P2y-purinoceptor antagonist in some systems, on the stimulatory effect of adenosine 5'-triphosphate (ATP) on [3H]-phosphatidylcholine secretion was examined in primary cultures of rat type II pneumocytes prelabelled by overnight culture with [3H]-choline. 2. Cibacron blue alone stimulated phosphatidylcholine secretion in a concentration-dependent manner in the range 10(-4)-10(-3) M. At a concentration of 10(-4) or lower, cibacron blue had no effect on ATP-induced phosphatidylcholine secretion but at 10(-4)-10(-3) M it increased the effect of ATP. Enhancement of the ATP effect was apparent whether cibacron blue was added before or together with ATP. Cibacron blue also increased ATP-induced secretion in the presence of the P1-purinoceptor antagonist, xanthine amine congener (10(-5) M). 3. The stimulatory effect of cibacron blue on phosphatidylcholine secretion was additive to those of 5' (N-ethylcarboxyamido) adenosine (NECA) and terbutaline but less than additive to that of ATP. 4. Cibacron blue alone had no effect on formation of cyclic AMP or inositol phosphate and when added simultaneously with ATP it did not affect the ATP-induced increase in these second messengers. Preincubation of the cells with cibacron blue before addition of ATP, however, resulted in antagonism of the ATP-induced increase in cyclic AMP and inositol phosphates. Preincubation with ATP had the same effect. The stimulatory effects of NECA and terbutaline on cyclic AMP formation were enhanced by preincubation with cibacron blue. 5. Thus, ATP-induced phosphatidylcholine secretion in type II cells is not diminished by the P2y-antagonist, cibacron blue.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Heart failure is known to be a complication of insulin-dependent (IDDM) and noninsulin-dependent diabetes mellitus (NIDDM) even in the absence of coronary heart disease or hypertension. The mechanisms leading to diabetic cardiomyopathy are unknown. The aim of the study was to characterize structural and functional alterations in hyperinsulinemic Zucker diabetic fatty (ZDF) rats treated with or without insulin. Diabetic animals showed a twofold increase in cardiomyocyte volume with increased left ventricular ANP but not BNP mRNA levels in spite of a reduced plasma renin activity (PRA) 2 months after onset of diabetes compared to nondiabetic littermates. These changes were associated with an increase in left ventricular performance as assessed by echocardiography. Insulin treatment led to a significant increase in body weight (BW), total heart weight, myocardial protein content, and left ventricular mass (LVM). Perivascular fibrosis and laminin thickness were significantly augmented in diabetic rat myocardium irrespective of insulin treatment, whereas interstitial collagen I and fibronectin were similarly found in diabetic and control myocardium. Initial stages of diabetic cardiomyopathy in hyperinsulinemic rats are characterized by cardiomyocyte hypertrophy and enhanced cardiac contractility. It is suggested that hyperinsulinemia may be involved in cardiac hypertrophy.  相似文献   
4.
BACKGROUND: Open tension-free methods of groin hernia repair have been widely adopted despite little rigorous evaluation. METHODS: Information was assimilated from all randomized or quasi-randomized trials comparing open mesh with open non-mesh methods to assess benefits and safety. Electronic databases were searched and members of the EU Hernia Trialists Collaboration consulted to identify trials. Prespecified data items were extracted from reports, and quantitative or, if not possible, qualitative meta-analysis was performed. RESULTS: Fifteen eligible trials, which included 4005 participants, were identified. There were similar numbers of complications in each group, with few data to address short-term pain and length of stay in hospital. Return to usual activities was quicker in the mesh group for seven of ten trials (P not significant). There were fewer reported recurrences in the mesh groups: overall 21 (1.4 per cent) of 1513 versus 72 (4.4 per cent) of 1634 (odds ratio 0.39 (95 per cent confidence interval 0.25-0. 59); P < 0.001). CONCLUSION: Although the rigorous search maximized trial identification, formal meta-analysis was limited by the variation in trial reporting. Within the data available, mesh repair was associated with fewer recurrences.  相似文献   
5.
BACKGROUND: The place of laparoscopic groin hernia repair remains controversial. Individual randomized controlled trials alone have not provided statistically reliable results when considering recurrence, potentially serious complications and chronic pain. METHODS: A rigorous systematic review was performed of published data from all relevant randomized or quasi-randomized trials. Electronic databases were searched and members of the EU Hernia Trialists Collaboration consulted to identify trials. Prespecified data items were extracted from reports and, where possible, quantitative meta-analysis was performed. RESULTS: Thirty-four published reports of eligible trials were included, involving 6804 participants. Sample sizes ranged from 20 to 1051, with follow-up from 6 weeks to 36 months. Duration of operation was longer in the laparoscopic groups (P < 0.001, Sign test). Operative complications were uncommon for both methods, but visceral and vascular injuries were more frequent in the laparoscopic group (4.7 per 1000 versus 1. 1 per 1000). Postoperative pain was less among laparoscopic groups (P = 0.08). Length of hospital stay did not differ significantly between groups (P = 0.50), but return to usual activity was earlier for laparoscopic groups (P < 0.001). Chronic pain and numbness were reported for only a small minority of trials. Overall, recurrences did not differ between groups, but comparison of laparoscopic with open non-mesh repair favoured laparoscopic methods, significantly so for transabdominal preperitoneal repair (Peto odds ratio 0.56 (95 per cent confidence interval 0.33-0.93); P = 0.026). CONCLUSION: Although the rigorous search maximized trial identification, variation in trial reporting made formal meta-analysis difficult. Laparoscopic repair was associated with less postoperative pain and more rapid return to normal activities, but it takes longer to perform and may increase the risk of rare, but serious, complications.  相似文献   
6.
7.

Aim:

The most recent study on the clinicopathological features of gastric carcinoma from the University College Hospital (UCH), Ibadan, was done in 2000. The aim of this study is to update the knowledge on the clinicopathological features of gastric carcinoma diagnosed in the Pathology Department of the UCH Ibadan between 2000 and 2011.

Materials and Methods:

This was a 12-year retrospective review of clinical and demographic data and the histopathological features of gastric cancers diagnosed at the Pathology Department of the UCH. The chi square test, Fisher''s exact test, and the t-independent test were used as applicable in the statistical analyses.

Results:

A total of 117 cases of gastric carcinoma were histologically diagnosed at the Pathology Department of UCH, Ibadan in this period giving a relative ratio frequency of 1.38% for all cancers. It represented 18.4% of all gastrointestinal tract malignancies diagnosed in the same period. There was a male preponderance with male:female ratio of 1.72:1; the middle-aged and elderly made up about 76.1% of cases. The disease was clinically and histologically advanced in 92.8% of cases. Gastric tumours were predominantly antral/ pyloric in 80% of cases and exophytic in 62.3% of cases. The intestinal histotype constituted 47.0% cases although a rise in the diffuse histological type was observed.

Conclusion:

There is a decline in the relative ratio frequency of gastric carcinoma in Ibadan; and a fall in the rate of the intestinal type of gastric carcinoma relative to the diffuse type when compared to previous studies from our centre.  相似文献   
8.
Lung ultrasound (LUS) has been increasingly used in diagnosing and monitoring of various pulmonary diseases in children. The aim of the current study was to evaluate its usefulness in children with persistent tachypnea of infancy (PTI). This was a controlled, prospective, cross‐sectional study that included children with PTI and healthy subjects. In patients with PTI, LUS was performed at baseline and then after 6 and 12 months of follow‐up. Baseline results of LUS were compared to (a) baseline high‐resolution computed tomography (HRCT) images, (b) LUS examinations in control group, and (c) follow‐up LUS examinations. Twenty children with PTI were enrolled. B‐lines were found in all children with PTI and in 11 (55%) control subjects (P < .001). The total number of B‐lines, the maximal number of B lines in any intercostal space, the distance between B‐lines, and pleural thickness were significantly increased in children with PTI compared to controls. An irregularity of the pleural line was found in all patients with PTI and in none of the healthy children. There were no significant changes in LUS findings in patients with PTI during the study period. The comparison of HRCT indices and LUS findings revealed significant correlations between the mean lung attenuation, skewness, kurtosis and fraction of interstitial pulmonary involvement, and the number of B‐lines as well as the pleural line thickness. LUS seems to be a promising diagnostic tool in children with PTI. Its inclusion in the diagnostic work‐up may enable to reduce the number of costly, hazardous, and ionizing radiation‐based imaging procedures.  相似文献   
9.
Cystic fibrosis (CF) lung disease severity is largely independent on the CF transmembrane conductance regulator (CFTR) genotype, indicating the contribution of genetic modifiers. The chemokine receptors CXCR1 and CXCR2 have been found to play essential roles in the pathogenesis of CF lung disease. Here, we determine whether genetic variation of CXCR1 and CXCR2 influences CF lung disease severity. Genomic DNA of CF patients in Germany (n = 442) was analysed for common variations in CXCR1 and CXCR2 using a single-nucleotide polymorphism (SNP) tagging approach. Associations of CXCR1 and CXCR2 SNPs and haplotypes with CF lung disease severity, CXCR1 and CXCR2 expression, and neutrophil effector functions were assessed. Four SNPs in CXCR1 and three in CXCR2 strongly correlated with age-adjusted lung function in CF patients. SNPs comprising haplotypes CXCR1_Ha and CXCR2_Ha were in high linkage disequilibrium and patients heterozygous for the CXCR1-2 haplotype cluster (CXCR1-2_Ha) had lower lung function compared with patients with homozygous wild-type alleles (forced expiratory volume in 1 s ≤ 70% predicted, OR 7.24; p = 2.30 × 10(-5)). CF patients carrying CXCR1-2_Ha showed decreased CXCR1 combined with increased CXCR2 mRNA and protein expression, and displayed disturbed antibacterial effector functions. CXCR1 and CXCR2 genotypes modulate lung function and antibacterial host defence in CF lung disease.  相似文献   
10.
During the last 30 years, life expectancy in patients with cystic fibrosis has significantly improved. In Germany, almost half of the 8500 patients are 18 years or older. Older patients have increased rates of cystic fibrosis typical complications, In addition the characteristic complications of adulthood, including arterial hypertension, hyperlipidemia, and cardiovascular diseases, occur. Also crisis of marriage or loss of work place, as well as family planning measures including in-vitro-fertilization are problems merely of the adult cystic fibrosis patient. Therefore adult patients should be treated in a centre specialized on adults. At the moment, in Germany only one third of all adult patients are followed up in an adult center, many patients are treated in age-independent centers, and also a significant number is treated in small clinics. In this article models for transition currently established in Germany are described and occurring problems with their implementation are discussed  相似文献   
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