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51.
Pirlich M Biering H Gerl H Ventz M Schmidt B Ertl S Lochs H 《The Journal of clinical endocrinology and metabolism》2002,87(3):1078-1084
Cushing's syndrome (CS) is associated with low fat-free mass, but it is unclear whether hypercortisolism causes a loss of whole body protein. Body composition was studied prospectively in 15 patients with untreated CS (n = 14 pituitary adenoma; n = 1 adrenal adenoma), in 15 nonobese healthy controls, and in 15 weight-matched obese controls by 3 different methods: total body potassium counting (TBP), bioelectrical impedance analysis (BIA), and anthropometry. In 6 patients, body composition was studied before and within 6 months after pituitary surgery. In CS patients and weight-matched controls, body weight and total body fat were significantly higher than in nonobese controls. In CS patients, TBP was 18.4% lower than predicted, whereas in weight-matched controls TBP was 7.1% higher than predicted. As compared with nonobese and weight-matched controls, in CS patients TBP indicated a significant loss of body cell mass (BCM) of -20.2 and -21.1%, respectively. A significantly reduced arm muscle area of -21.3% compared with weight-matched controls also indicated a loss of whole body protein. In CS, however, BIA overestimated BCM when compared with TBP by +18% and agreement between BIA and TBP in the individual patient was poor (limits of agreement plus minus 27.6%), indicating the invalidity of standard BIA equations in this population. Measurements performed before and 6 months after successful pituitary surgery demonstrated a significant loss of body weight (-11%) and body fat (-33%), but BCM and muscle mass remained on a constant low level. In conclusion, this study shows that, in patients with CS, a significantly reduced BCM indicates a true protein loss. The second interesting finding is that in the early recovery after successful treatment of hypercortisolism patients lose body fat without gaining BCM or muscle mass. 相似文献
52.
Geier A Zollner G Dietrich CG Wagner M Fickert P Denk H van Rooijen N Matern S Gartung C Trauner M 《Hepatology (Baltimore, Md.)》2005,41(3):470-477
Cholestatic liver injury is associated not only with accumulation of bile acids but also with activation of proinflammatory cytokines. Common bile duct ligation (CBDL) induces sustained downregulation of the Na(+)/taurocholate cotransporter (Ntcp) in rodent liver. Although repression of Ntcp during endotoxemia is cytokine mediated, it is unclear whether inflammatory cytokines contribute to this downregulation in obstructive cholestasis. Cytokine inactivation in CBDL rats and mice was either performed directly with tumor necrosis factor alpha (etanercept) or interleukin 1 beta inactivation (anakinra/AMG 719) or indirectly Kupffer cell depletion via intraperitoneal administration of liposome-encapsulated dichloromethylene bisphosphonate. Protein and messenger RNA (mRNA) expression of Ntcp and short heterodimer partner (SHP) were analyzed via Western and Northern blotting. Key regulators of Ntcp (hepatocyte nuclear factor 1 alpha [HNF-1alpha], HNF-4alpha, retinoid X receptor alpha [RXRalpha]:retinoic acid receptor alpha [RARalpha]) were studied via electrophoretic mobility shift analysis and nuclear Western blot analysis. Both methods of cytokine inactivation failed to maintain Ntcp protein or mRNA expression within 3 days after CBDL in either rats or mice (20%-40% of sham controls), while SHP mRNA expression increased three- to five-fold. Decreased nuclear HNF-1alpha and HNF-4alpha protein levels (45% and 60% of sham controls, respectively) and HNF-1alpha binding activity (32% of sham controls) were not restored during cytokine inactivation after CBDL, indicating cytokine-independent mechanisms of Ntcp regulation. RXRalpha:RARalpha binding remained unchanged in all experimental conditions. In conclusion, during obstructive cholestasis accumulating bile acids per se, without major contribution of cytokines, leads to downregulation of Ntcp via repression of HNF-1alpha and HNF-4alpha. 相似文献
53.
Repair of erosions in rheumatoid arthritis does occur. Results from 2 studies by the OMERACT Subcommittee on Healing of Erosions 总被引:4,自引:0,他引:4
Sharp JT Van Der Heijde D Boers M Boonen A Bruynesteyn K Emery P Genant HK Herborn G Jurik A Lassere M McQueen F Østergaard M Peterfy C Rau R Strand V Wassenberg S Weissman B;Subcommittee on Healing of Erosions of the OMERACT Imaging Committee 《The Journal of rheumatology》2003,30(5):1102-1107
The committee was charged with determining whether healing of erosions in rheumatoid arthritis (RA) occurs. Two exercises were performed: The first asked the committee members, as a panel of experts, to express agreement or disagreement with the presence of improvement and features of bone reaction to injury in images submitted by members as examples of healing. The second presented panel members with 28 pairs of serial images, 14 chosen to illustrate progression and 14 chosen to illustrate repair. Agreement was tested on 8 items: global judgment on which image in the pair was better, relative size of the erosion in the 2 images, judgment on which image was first, presence and extent of sclerosis, cortication, filling-in, remodeling, and reconstituting normal structure. Our results showed good agreement, among the 15 respondents, on global assessment of which image was better and which image showed the smaller erosion. Correct assignment of sequence was only slightly better than expected by chance (in 65% of the cases). Agreement was poor regarding the presence of morphologic features of bone repair. A majority of a panel of experts agreed on which 2nd images in a set of paired, serial images represented improvement and which showed progression based on global assessment of which was better and on size of erosion. Features of bone repair were not distinctive and did not enable the panel to deduce the correct sequence of the serial images. This study provides evidence that repair of bone damage in RA does occur, resulting in some degree of improvement, which was recognized by a majority of a panel of experts. 相似文献
54.
Klaus-Peter Ratzmann Siegfried Knospe Peter Heinke Bernd Schulz 《Acta diabetologica》1979,16(1):67-75
Summary We have studied the interrelationship of total body fat mass, carbohydrate tolerance and IRI response in 17 non-obese and
obese subjects, who were suspected of having early diabetes. We carried out an i.v. glucose infusion test consisting of a
priming injection of 0.33 g/kg followed by constant glucose infusion of 12 mg/kg/min in all persons. Total body fat mass was
estimated by the tritium dilution method. There was a positive correlation of body fat mass, fasting glucose concentration
and blood glucose concentration at 150 min as well as a strong correlation between body fat mass and BG area 60–120 min as
parameters of carbohydrate tolerance in all subjects, i.e. the degree of carbohydrate intolerance was directly related to
the quantity of total body fat mass. A similar correlation was found when the non-obese and obese groups were analyzed separately.
In neither group did total body fat mass correlate with parameters of IRI response. In obese subjects with pathological carbohydrate
tolerance, however, a positive correlation of basal IRI concentration and total body fat mass was found. Furthermore, a close
relation between basal IRI level and parameters of carbohydrate tolerance could be demonstrated in obese subjects. The present
study failed to demonstrate any correlation of parameters of carbohydrate tolerance and glucose-induced IRI response in either
group. Thus, the significant relationship between body fat mass and degree of carbohydrate intolerance indicates that total
body fat mass plays an important role in the disturbance of blood glucose homeostasis in early diabetes with and without obesity.
Investigation performed within the medical research project ‘Diabetes mellitus and disturbances of lipid metabolism’, Ministry
of Health, GDR. 相似文献
55.
Markus Dold Martin Aigner Rupert Lanzenberger Siegfried Kasper 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(9)
Background:
Many patients with obsessive-compulsive disorder do not respond adequately to serotonin reuptake inhibitors. Augmentation with antipsychotic drugs can be beneficial in this regard. However, since new relevant randomized controlled trials evaluating new antipsychotics were conducted, a recalculation of the effect sizes appears necessary.Methods:
We meta-analyzed all double-blind, randomized, placebo-controlled trials comparing augmentation of serotonin reuptake inhibitors with antipsychotics to placebo supplementation in treatment-resistant obsessive-compulsive disorder. The primary outcome was mean change in the Yale-Brown Obsessive–Compulsive Scale total score. Secondary outcomes were obsessions, compulsions, response rates, and attrition rates. The data collection process was conducted independently by 2 authors. Hedges’s g and risks ratios were calculated as effect sizes. In preplanned meta-regressions, subgroup analyses, and sensitivity analyses, we examined the robustness of the results and explored reasons for potential heterogeneity.Results:
Altogether, 14 double-blind, randomized, placebo-controlled trials (n=491) investigating quetiapine (N=4, n=142), risperidone (N=4, n=132), aripiprazole (N=2, n=79), olanzapine (N=2, n=70), paliperidone (N=1, n=34), and haloperidol (N=1, n=34) were incorporated. Augmentation with antipsychotics was significantly more efficacious than placebo in Yale-Brown Obsessive–Compulsive Scale total reduction (N=14, n=478; Hedges’s g=-0.64, 95% CI: -0.87 to -0.41; P=<.01). Aripiprazole (Hedges’s g=-1.35), haloperidol (Hedges’s g=-0.82), and risperidone (Hedges’s g=-0.59) significantly outperformed placebo. Antipsychotics were superior to placebo in treating obsessions, compulsions, and achieving response. There was no between-group difference concerning all-cause discontinuation. The nonsignificant meta-regressions suggest no influence of the antipsychotic dose or baseline symptom severity on the meta-analytic results.Conclusions:
According to our findings, antipsychotic augmentation of serotonin reuptake inhibitors can be regarded as an evidence-based measure in treatment-resistant obsessive-compulsive disorder. 相似文献56.
Christoph Josef Spindelegger Konstantinos Papageorgiou Renate Grohmann Rolf Engel Waldemar Greil Anastasios Konstantinidis Marcus Willy Agelink Stefan Bleich Eckart Ruether Sermin Toto Siegfried Kasper 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(4)
57.
Bernard Lakowski Siegfried Hekimi 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(22):13091-13096
Low caloric intake (caloric restriction) can lengthen the life span of a wide range of animals and possibly even of humans. To understand better how caloric restriction lengthens life span, we used genetic methods and criteria to investigate its mechanism of action in the nematode Caenorhabditis elegans. Mutations in many genes (eat genes) result in partial starvation of the worm by disrupting the function of the pharynx, the feeding organ. We found that most eat mutations significantly lengthen life span (by up to 50%). In C. elegans, mutations in a number of other genes that can extend life span have been found. Two genetically distinct mechanisms of life span extension are known: a mechanism involving genes that regulate dauer formation (age-1, daf-2, daf-16, and daf-28) and a mechanism involving genes that affect the rate of development and behavior (clk-1, clk-2, clk-3, and gro-1). We find that the long life of eat-2 mutants does not require the activity of DAF-16 and that eat-2; daf-2 double mutants live even longer than extremely long-lived daf-2 mutants. These findings demonstrate that food restriction lengthens life span by a mechanism distinct from that of dauer-formation mutants. In contrast, we find that food restriction does not further increase the life span of long-lived clk-1 mutants, suggesting that clk-1 and caloric restriction affect similar processes. 相似文献
58.
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60.
Marwin Bannehr Ulrike Kahn Josephin Liebchen Maki Okamoto Valentin Hähnel Christian Georgi Victoria Dworok Christoph Edlinger Michael Lichtenauer Tanja Kücken Siegfried Kropf Anja Haase-Fielitz Christian Butter 《The Canadian journal of cardiology》2021,37(7):1086-1093
BackgroundFunctional tricuspid regurgitation (TR) is a frequent finding in echocardiography. Despite general consent that right ventricular (RV) dysfunction impacts outcome of patients with TR, it is still unknown which echocardiographic parameters most accurately reflect prognosis. In this study we aimed to evaluate the prevalence of RV dysfunction and its prognostic value in patients with TR.MethodsData from 1089 consecutive patients were analysed. Tricuspid annular plane systolic excursion (TAPSE), fractional area change, and right ventricular free wall longitudinal strain (RV strain) were used to define RV dysfunction. Patients were followed for 2-year all-cause mortality. For prediction of survival, reclassification and C statistics of RV functional parameters using TR grade as reference model were performed.ResultsAmong the patients studied, 13.9% showed no TR, 61.2% had mild TR, 19.6% had moderate TR, and 5.3% had severe TR. The TR grade was associated with increased mortality (log rank, P < 0.001). Impaired RV strain and TAPSE were independent predictors for mortality (RV: hazard ratio [HR], 1.130; 95% confidence interval [CI], 1.099-1.160; P < 0.001; TAPSE: HR, 1.131; 95% CI, 1.085-1.175; P < 0.001). Both RV strain and TAPSE improved the reference model for survival prediction (RV: integrated discrimination improvement [IDI], 0.184; 95% CI, 0.146-0.221; P < 0.001; TAPSE: IDI, 0.057; 95% CI, 0.037-0.077; P < 0.001).ConclusionsEchocardiographic evaluation of RV function appears to useful for patients with TR. Assessment of RV strain provides additional value for prediction of 2-year mortality. 相似文献