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21.
Increased glomerular angiotensin II binding in rats exposed to a maternal low protein diet in utero 总被引:2,自引:0,他引:2
In the rat, protein restriction during pregnancy increases offspring blood pressure by 20–30 mmHg. We have shown in an earlier study that this is associated with a reduction in nephron number and increased glomerular sensitivity to angiotensin II (Ang II) in vivo . Hence, we hypothesized that exposure to a maternal low-protein diet increases glomerular Ang II AT1 receptor expression and decreases AT2 receptor expression. To test this hypothesis, pregnant Wistar rats were fed isocalorific diets containing either 18% (control) or 9% (LP) protein from conception until birth. At 4 weeks of age, the kidneys of male offspring were harvested to measure cortical AT1 and AT2 receptor expression, 125 I-Ang II glomerular binding, tissue renin activity, tissue Ang II and plasma aldosterone concentrations. AT1 receptor expression was increased (62%) and AT2 expression was decreased (35%) in LP rats. Maximum 125 I-Ang II (125 I-Ang II) binding ( B max ) was increased in LP rats (control n = 9, 291.6 ± 27.4 versus LP n = 7, 445.7 ± 27.4 fmol (mg glomerular protein)−1 , P < 0.01), but affinity ( K D ) was not statistically different from controls (control 2.87 ± 0.85 versus LP 0.84 ± 0.20 pmol 125 I-Ang II, P = 0.059). Renal renin activity, tissue Ang II and plasma aldosterone concentrations did not differ between control and LP rats. Increased AT1 receptor expression in LP rat kidneys is consistent with greater haemodynamic sensitivity to Ang II in vivo . This may result in an inappropriate reduction in glomerular filtration rate, salt and water retention, and an increase in blood pressure. 相似文献
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Patricia M. Lenhart-Pendergrass Lindsay J. Caverly Brandie D. Wagner Scott D. Sagel Jerry A. Nick John J. LiPuma Stacey L. Martiniano 《Journal of cystic fibrosis》2021,20(2):310-315
BackgroundMolecular diagnostics have led to the identification of a broad range of bacterial species in cystic fibrosis (CF) including Inquilinus. The clinical significance of Inquilinus in CF has not been thoroughly characterized.MethodsRetrospective, case-control study of persons with CF from two CF centers with at least one respiratory culture positive for Inquilinus spp. compared with age-matched CF controls with chronic Pseudomonas aeruginosa. Percent predicted forced expiratory volume in one second (ppFEV1) and body mass index percentile (BMI) were modeled from time of first positive culture up to 5 years later. Rates of pulmonary exacerbations were compared. Inquilinus isolates were genotyped to evaluate strain diversity.ResultsSeventeen patients with Inquilinus infection were identified with a mean age of 13 years at first positive culture. Most cases had multiple cultures positive for Inquilinus. ppFEV1 was not different between cases versus controls (80.2% vs 81.6%, p = 0.97 at baseline, 67.5% vs. 73.3%, p = 0.82 at 5 years). Patients were undernourished and BMI percentiles did not differ between groups (30.7% vs 43.4%, p = 0.32 at baseline, 37.9% vs. 37.6%, p = 0.98 at 5 years). There was no difference in the pulmonary exacerbation rate (3.0/year vs 2.5/year, p = 0.34). Genotyping showed diverse genetic strains between patients.ConclusionsInquilinus can present in childhood and is often associated with chronic infection in CF. Lung function and nutrition status at time of detection, lung function decline, and pulmonary exacerbation rates in Inquilinus cases were similar to those with chronic P. aeruginosa, a well-established CF pathogen. 相似文献
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Alan J Howell Andrew Burchett Nicholas Heebner Cody Walker Alec Baunach Asia Seidt Tim L Uhl 《International Journal of Sports Physical Therapy》2022,17(4):695
BackgroundPrevious research has demonstrated the benefits of both stabilization and non-stabilization of the scapula during stretching in individuals with posterior shoulder tightness, but limited evidence exists in patients with shoulder pain.Hypothesis/PurposeThe aim of this study was to determine the effect of stabilized scapular stretching on patients with shoulder pain. The primary hypothesis of this study is that stabilized scapular stretching will improve glenohumeral motion and pain compared to non-stabilized stretch program. A secondary hypothesis of this study is that stabilized scapular stretching will produce greater improvement in function compared to the non-stabilized stretching program.Study DesignRandomized Clinical TrialMethodsSixteen patients with sub-acromial pain associated with tendinopathy and associated pathologies presenting to physical therapy were randomized into two groups (stabilized or non-stabilized scapular stretching). Baseline pain and range of motion were measured prior to and following each treatment session for three visits that occurred over the course five to seventeen days depending on the patients availability. The dependent measurements were stabilized horizontal adduction, stabilized internal rotation, stabilized shoulder flexion, non-stabilized shoulder flexion, and current pain level.ResultsPatients in the scapular stabilization stretching group increased horizontal adduction 40° (CI95 31, 48°) compared to the non-stabilization stretching group increase of 8° (CI95 0, 17°) over the course of the three treatments (p<0.001). Similarly, the stabilized stretching group increased internal rotation 48° (CI95 26, 69°) compared to the non-stabilized stretching group increase of 26° (CI95 4, 48°) (p=0.001). Pain decreased in the stabilized stretching group by 1.4 points (CI95 -0.4, 3.2) but increased slightly in non-stabilized group by -0.5 points (CI95 -2.3, 1.3) which was not a clinically meaningful change. (p=0.03)ConclusionStabilized scapular stretching was more effective than non-stabilized stretching at gaining shoulder mobility in patients with shoulder pain. Benefits were immediate and sustained between treatment sessions. Stretching interventions improved range of motion but had limited effect on shoulder pain.Level of Evidence2 相似文献
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The influence of children's self-report trait anxiety and depression on visual search for emotional faces 总被引:2,自引:0,他引:2
Hadwin JA Donnelly N French CC Richards A Watts A Daley D 《Journal of child psychology and psychiatry, and allied disciplines》2003,44(3):432-444
BACKGROUND: This study presents two experiments that investigated the relationship between 7- and 10-year-olds' levels of self-report trait anxiety and depression and their visual search for threatening (angry faces) and non-threatening (happy and neutral faces) stimuli. METHOD: In both experiments a visual search paradigm was used to measure participants' reaction times to detect the presence or absence of angry, happy or neutral schematic faces (Experiment 1) or cartoon drawings (Experiment 2). On target present trials, a target face was displayed alongside three, five or seven distractor items. On target absent trials all items were distractors. RESULTS: Both experiments demonstrated that on target absent (but not present) trials, increased levels of anxiety produced significantly faster search times in the angry face condition, but not in the neutral condition. In Experiment 2 there was some trend towards significance between anxiety and searches for happy faces in absent trials. There were no effects of depression on search times in any condition. CONCLUSION: The results support previous work highlighting a specific link between anxiety and attention to threat in childhood. 相似文献