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81.
ABSTRACT

Children and adolescents with Attention De?cit Hyperactivity Disorder (ADHD) have a high prevalence of obesity, but the relationship between these two problems is not clear. Chronotype preferences may be one of the possible mechanisms underlying the link between ADHD and obesity. This is the ?rst study to investigate whether chronotype preferences are a mechanism linking ADHD symptoms to obesity in children and adolescents. This cross-sectional study included 110 drug-naive children and adolescents aged 7–17 years with ADHD. The Kiddie Schedule for Affective Disorders and Schizophrenia‐Present and Lifetime Version (K‐SADS‐PL) was used to diagnose ADHD or to exclude psychiatric comorbidity. The Conners’ Parents Rating Scale-Revised Short Version (CPRS-RS) and Children’s Chronotype Questionnaire (CCQ) were used to assess the severity of ADHD symptoms and chronotype preferences. Body mass index (BMI) was calculated and classified according to national age- and gender-specific reference values. The participants were divided into three groups as normal weight (<85%, n = 38), overweight (85%-95%, n = 30) and obesity (>95%, n = 42) according to their BMI percentile. There were statistically significant differences between the three groups in terms of chronotype preference (p = .000). Morningness preference was 86.84% in the normal BMI group and 26.19% in the obese BMI group. Eveningness preference was 7.89% in the normal BMI group and 61.90% in the obese BMI group. There was a correlation between the BMI percentile scores and the morningness/eveningness scale (M/E) scores. Moreover, there was a correlation between the BMI percentile scores and the oppositional and ADHD index scores. According to logistic regression analysis, the odds ratio of having evening type for obesity was 5.66 and the odds ratio of having morning type for normal weight was 13.03. Independently from ADHD symptoms, eveningness was directly related to obesity and morningness was directly related to normal weight. Prospective studies should be performed to better understand the relationship between ADHD, overweight/obesity and chronotype.  相似文献   
82.
Chromosome analysis on different breed types of water buffaloes (Bubalus bubalis) was undertaken to identify their karyotypes and to determine the pattern of chromosome segregation in crossbred water buffaloes. Altogether, 75 purebred and 198 crossbred buffaloes including 118 from Malaysia and 80 from the Philippines, were analyzed in this study. The diploid chromosome number of the swamp buffalo from both countries was 48 and that of the river buffalo was 50, while all F1 hybrids exhibited 49 chromosomes. The F2 hybrids consisted of three different karyotype categories (2n = 48, 2n = 49, and 2n = 50), whereas the backcrosses included two different karyotype categories each, with 2n = 48 and 2n = 49 in the three quarters swamp types and 2n = 49 and 2n = 50 in the three quarters river types. Chi-square tests on pooled data from Malaysia and the Philippines indicated that the distribution of different karyotype categories of F2 animals did not deviate significantly from the 1:2:1 ratio expected if only balanced gametes with 24 and 25 chromosomes were produced by the F1 hybrids. In the three quarters swamp and three quarters river types, the respective karyotypic categories were in ratios approximating 1:1. The distribution of chromosome categories among the F2 hybrids and backcrosses suggests that only genetically balanced gametes of the F1 hybrids are capable of producing viable F2 and backcross generations.  相似文献   
83.
Kandilci HB  Gumusel B  Lippton H 《Peptides》2008,29(8):1321-1328
The present study was designed to investigate the effects of rat intermedin/adrenomedullin2 (rIMD), an agonist for calcitonin-like calcitonin receptors (CRLR), on the isolated rat pulmonary arterial rings (PA). When PA were precontracted with 9,11-dideoxy-11alpha,9alpha-epoxymethanoprostaglandin F2alpha (U-46619), rIMD (10(-11) to 10(-6)M) induced concentration-dependent relaxation. The pulmonary vasorelaxant response (PVR) to rIMD in PA were completely inhibited by endothelium removal, NG-nitro-L-arginine-methyl-ester (L-NAME), l-N5-(1-iminoethyl)-ornithine hydrochloride (l-NIO) or 1H-[1,2,4] oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). The PVR to rIMD were also significantly attenuated by a protein kinase inhibitor, Rp-8-bromo-beta-phenyl-1,N2-ethenoguanosine 3':5'-cyclic monophosphorothioate sodium salt hydrate (Rp-8-Br-PETcGMPs), cholera toxin and abolished by tetraethylammonium chloride (TEA), iberiotoxin and precontraction with KCl. The relaxant effect was not affected by 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ22536), (9S,10S,12R)-2,3,9,10,11,12-hexahydro-10-hydroxy-9-methyl-1-oxo-9,12-epoxy 1H diindolo [1,2,3fg:3',2',1'kl] pyrrolo [3,4-i] [1,6] benzodiazocine-10-carboxylic acid hexyl ester (KT5720), meclofenamate, glybenclamide or apamin. In parallel with SQ22536 and KT5720 results rolipram pretreatment did not alter the rIMD-induced PVR. The PVR to rIMD was potentialized either in the presence of zaprinast or sildenafil. Since the PVR to rIMD was also significantly reduced by rCGRP(8-37) and hADM(22-52) and rIMD(17-47), the present data suggest that rIMD produces PVR by acting in an indiscriminant manner on functional, and possibly different, endothelial CRLR. In conclusion, rIMD stimulates endothelial CRLR are coupled to release of nitric oxide, activation of guanylate cyclases, and promotion of hyperpolarization through large conductance calcium-activated K(+) channels in rat main PA.  相似文献   
84.

Background

Chronic smoking is the main risk factor for chronic obstructive pulmonary disease. Knowledge on the response to the initial smoke exposures might enhance the understanding of changes due to chronic smoking, since repetitive acute smoke effects may cumulate and lead to irreversible lung damage.

Methods

We investigated acute effects of smoking on inflammation in 16 healthy intermittent smokers in an open randomised cross-over study. We compared effects of smoking of two cigarettes on inflammatory markers in exhaled air, induced sputum, blood and urine at 0, 1, 3, 6, 12, 24, 48, 96 and 192 hours and outcomes without smoking. All sputum and blood parameters were log transformed and analysed using a linear mixed effect model.

Results

Significant findings were: Smoking increased exhaled carbon monoxide between 0 and 1 hour, and induced a greater decrease in blood eosinophils and sputum lymphocytes between 0 and 3 hours compared to non-smoking. Compared to non-smoking, smoking induced a greater interleukin-8 release from stimulated blood cells between 0 and 3 hours, and a greater increase in sputum lymphocytes and neutrophils between 3 and 12 hours.

Conclusion

We conclude that besides an increase in inflammation, as known from chronic smoking, there is also a suppressive effect of smoking two cigarettes on particular inflammatory parameters.  相似文献   
85.

Background

Inflammation in the airways and lung parenchyma underlies fixed airway obstruction in chronic obstructive pulmonary disease. The exact role of smoking as promoting factor of inflammation in chronic obstructive pulmonary disease is not clear, partly because studies often do not distinguish between current and ex-smokers.

Methods

We investigated airway inflammation in sputum and bronchial biopsies of 34 smokers with chronic obstructive pulmonary disease (9 Global initiative for Chronic Obstructive Lung Disease stage 0, 9 stage I, 10 stage II and 6 stage III) and 26 asymptomatic smokers, and its relationship with past and present smoking habits and airway obstruction.

Results

Neutrophil percentage, interleukin-8 and eosinophilic-cationic-protein levels in sputum were higher in chronic obstructive pulmonary disease (stage I-III) than asymptomatic smokers. Inflammatory cell numbers in bronchial biopsies were similar in both groups. Current smoking correlated positively with macrophages: in bronchial biopsies in both groups, and in sputum in chronic obstructive pulmonary disease. Pack-years smoking correlated positively with biopsy macrophages only in chronic obstructive pulmonary disease.

Conclusion

Inflammatory effects of current smoking may mask the underlying ongoing inflammatory process pertinent to chronic obstructive pulmonary disease. This may have implications for future studies, which should avoid including mixed populations of smokers and ex-smokers.  相似文献   
86.
We recently described an isotope dilution reversed-phase liquid chromatography-atmospheric pressure chemical ionization-ion-trap-tandem mass spectrometry (HPLC-APCI-MS/MS) method for the quantitative determination of oxidized amino acids in human urine, including o,o'-dityrosine, a specific marker of protein oxidation. In the present study, we investigated the possibility to use a triple quadrupole instrument for the analysis of this biomarker in urine. The two instruments were compared in terms of sensitivity, specificity and reproducibility. Results showed that the triple quadrupole instrument reaches 2.5-fold higher sensitivity (LOD=0.01 microM) compared to the previously used ion-trap instrument. Precision of the present assay is as follows: in-day variation is 4.6% and inter-day variation is 17%. The currently developed method was applied to a group of smoker urine samples. The mean urinary o,o'-dityrosine concentration was 0.08+/-0.01 microM. Expressed per urinary creatinine concentration, this corresponds to 10.1+/-0.4 micromol/mol creatinine. This is comparable to the previously reported values of 5.8+/-0.3 micromol/mol creatinine in non-smokers night-time urines, and 12.3+/-5 micromol/mol creatinine in day-time urines measured by the ion-trap instrument.  相似文献   
87.
The Val762Ala polymorphism poly [ADP-ribose] polymerase 1 (PARP1) gene [ADPRT (adenosine diphosphate ribosyltransferase) gene] affects enzymatic activity, which modulates cancer susceptibility among human populations. Individual data on 13,745 cases and 16,947 controls from 28 published case–control studies were re-evaluated. Odds ratios (OR) were estimated for ethnic group, cancer type, smoking joint effects and studies confined to the Hardy–Weinberg equilibrium. We applied subgroup, sensitivity and outlier analyses as well as the Bonferroni correction for multiple testing. The results show strong evidence that the variant (C) allele confers significant increased risk in the Chinese (OR 1.20–1.44, P?<?0.0001–0.002), exacerbated by smoking (OR 1.66–2.53, P?<?0.0001) and joint interaction with XRCC1 Arg399Gln (OR 1.39, P?<?0.0001) as well as adjustment for tumor type (gastric carcinoma ORs 1.39–2.01, P?<?0.0001). These significant effects were unaltered following conservative correction for multiple tests. By contrast, this procedure erased the protective significance in Caucasians, but not in two American subgroups, (i) those in the brain tumor category (0.77–0.79, P?<?0.0001) and (ii) smokers in the dominant model (OR 0.86, P?<?0.0001). These differential findings between the two ethnicities maybe correlated with significantly (P?<?0.0001) greater allele frequency of the variant allele (C) among the Chinese compared to Caucasians. Our racial and tissue-specific summary estimates imply consideration of the Val762Ala polymorphism as candidate gene marker for screening cancer patients’ best suited for PARP inhibitor therapy.  相似文献   
88.
We evaluated the effects of dipyrido [3,2-a:2′,3′-c] phenazine (dppz) Au(III) complex ([Au(dppz)Cl2]Cl) on apoptosis during chemically induced hepatocellular carcinoma. 48 male Spraque-Dawley rats were divided into six groups; group I (control), group II [Dimethyl sulfoxide (DMSO)], group III ([Au(dppz)Cl2]Cl), group IV [diethylnitrosamine + Phenobabital (DEN + PB)], group V (DEN + PB + [Au(dppz)Cl2]Cl (2nd week)), and group VI (DEN + PB + [Au(dppz)Cl2]Cl (7th week). The rats in groups IV through VI were administrated with DEN in a single dose of intraperitoneal 175 mg/kg. After 2 weeks of DEN administration, these groups of rats were given daily PB in a dose of 500 ppm. In group V, after two weeks of DEN administration, [Au(dppz)Cl2]Cl complex (2 mg/kg) was given once a week by intraperitoneal injection. In the group VI, the rats were given a dose of 2 mg/kg [Au(dppz)Cl2]Cl complex once a week, 7 weeks after DEN administration. At the end of the study, blood and tissue samples were collected from the rats to determine levels of serum AST, ALT, and LDH, and caspase 3, p53, Bax, Bcl-2 and DNA fragmentation in liver. AST, ALT, LDH, and Bcl-2 levels were higher in group IV, compared to group I, but caspase 3 and p53 levels were lower. In group V, caspase 3, p53, Bax, and DNA fragmentation levels were higher than those of group IV. Caspase 3 and p53 levels increased in group VI compared with group IV. In conclusion, [Au(dppz)Cl2]Cl complex induced apoptosis by elevating levels of caspase 3, p53, Bax, and DNA fragmentation.  相似文献   
89.
Wood protection efficacy of borates against biological agents, flame retardancy, and suitability to the environment is well known. Since borates can be applied to timber as water based solutions, they are preferred economically as well. Even though they are highly mobile in wood, boron compounds are widely used in timber preservation. Borates migrate in liquid and increase the hygroscopicity of wood in damp conditions. This study deals with the physical restriction of water access in wood by impregnating water repellent agents into wood to limit amount of leachant and water absorption levels of wood after boron treatment. Borates were incorporated with polyethylene glycol-400 (PEG-400) their bulking effect in wood was considered. Results indicated that the amount of leachates from wood treated with borates in PEG-400 was remarkably higher compared to those of wood treated with the aqueous solutions of borates. Water absorption (WA) levels of wood treated with aqueous solutions of borates were higher than those of their treated samples with the solutions in PEG-400. Secondary treatments of wood with the water repellent (WR) chemicals following borate impregnation reduced the leaching of chemicals from wood in water and also WA of the specimens were less than those of the wood treated with only borates from aqueous and PEG solutions. Styrene (St) was the most effective monomer among the other agents used in terms of immobility effect on borates and WA.  相似文献   
90.

Background

The relationship between airway structural changes (remodeling) and airways hyperresponsiveness (AHR) is unclear. Asthma guidelines suggest treating persistent asthma with inhaled corticosteroids and long acting β-agonists (LABA). We examined the link between physiological function and structural changes following treatment fluticasone and salmeterol separately or in combination in a mouse model of allergic asthma.

Methods

BALB/c mice were sensitized to intraperitoneal ovalbumin (OVA) followed by six daily inhalation exposures. Treatments included 9 daily nebulized administrations of fluticasone alone (6 mg/ml), salmeterol (3 mg/ml), or the combination fluticasone and salmeterol. Lung impedance was measured following methacholine inhalation challenge. Airway inflammation, epithelial injury, mucus containing cells, and collagen content were assessed 48 hours after OVA challenge. Lungs were imaged using micro-CT.

Results and Discussion

Treatment of allergic airways disease with fluticasone alone or in combination with salmeterol reduced AHR to approximately naüve levels while salmeterol alone increased elastance by 39% compared to control. Fluticasone alone and fluticasone in combination with salmeterol both reduced inflammation to near naive levels. Mucin containing cells were also reduced with fluticasone and fluticasone in combination with salmeterol.

Conclusions

Fluticasone alone and in combination with salmeterol reduces airway inflammation and remodeling, but salmeterol alone worsens AHR: and these functional changes are consistent with the concomitant changes in mucus metaplasia.  相似文献   
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