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The course of autosomal dominant polycystic kidney disease (ADPKD) varies among individuals, with some reaching ESRD before 40 years of age and others never requiring RRT. In this study, we developed a prognostic model to predict renal outcomes in patients with ADPKD on the basis of genetic and clinical data. We conducted a cross-sectional study of 1341 patients from the Genkyst cohort and evaluated the influence of clinical and genetic factors on renal survival. Multivariate survival analysis identified four variables that were significantly associated with age at ESRD onset, and a scoring system from 0 to 9 was developed as follows: being male: 1 point; hypertension before 35 years of age: 2 points; first urologic event before 35 years of age: 2 points; PKD2 mutation: 0 points; nontruncating PKD1 mutation: 2 points; and truncating PKD1 mutation: 4 points. Three risk categories were subsequently defined as low risk (0–3 points), intermediate risk (4–6 points), and high risk (7–9 points) of progression to ESRD, with corresponding median ages for ESRD onset of 70.6, 56.9, and 49 years, respectively. Whereas a score ≤3 eliminates evolution to ESRD before 60 years of age with a negative predictive value of 81.4%, a score >6 forecasts ESRD onset before 60 years of age with a positive predictive value of 90.9%. This new prognostic score accurately predicts renal outcomes in patients with ADPKD and may enable the personalization of therapeutic management of ADPKD.  相似文献   
33.

Purpose

To evaluate aortic elasticity with MRI on young asymptomatic individuals with mutation of the smooth muscle myosin heavy chain in whom aortic enlargement is not present.

Materials and Methods

Aortic compliance, aortic distensibility, and pulse wave velocity (PWV) were semiautomatically measured from MRI in 8 asymptomatic subjects having a mutation of the MYH11 gene (M+) and 21 nonmutated relatives (M?) of similar age, sex, and blood pressure characteristics.

Results

Despite a similar aortic diameter in both groups, the aortic compliance and distensibility were significantly lower in M+ subjects compared with M? (0.84 ± 0.33 versus 2.03 ± 0.54 mm2/mmHg, 1.18 ± 0.62 10?3 versus 5.11 ± 1.58 10?3 mmHg?1, respectively), and PWV was significantly higher (5.35 ± 1.53 versus 3.60 ± 0.64 m.s?1). A threshold aortic compliance value of 1.3 mm2/mmHg separated the two groups. The receiver operating characteristics curve analysis indicated an optimal threshold of 2.9 10?3 mmHg?1 for aortic distensibility (sensitivity: 87.5%, specificity: 90%), and of 4.4 m.s?1 for PWV (sensitivity: 75%, specificity: 100%).

Conclusion

Young asymptomatic adults with MYH11 mutation have an aortic compliance impairment which is not detectable by the sole measurement of the aortic size. Aortic compliance measurement might be part of routine examination in patients suspected of inherited aortic disease even with a normal aortic diameter. J. Magn. Reson. Imaging 2008;28:1180–1187. © 2008 Wiley‐Liss, Inc.
  相似文献   
34.
Objective. To evaluate the supraspinatus muscle radiodensity on the outlet view as an indication of a tendon tear. Design and patients. Plain radiographs and magnetic resonance imaging (MRI) examinations were obtained on both shoulders of 40 subjects aged 23–70 years, including 13 asymptomatic volunteers and 27 patients. Two readers analyzed the superior contour and the heterogeneity of the supraspinatus muscle radiodensity and compared them with the MRI findings. Results and conclusion. Significant concordances (P<0.001) were found between the assessments of the superior contour and the heterogeneity of the muscle radiodensity, respectively, on plain radiographs and MR images. For the diagnosis of a full-thickness tear, the analysis of the superior contour and the heterogeneity of the muscle radiodensity reached an accuracy of 85% and 80% respectively. Stepwise discriminant analyses showed low to moderate benefit of considering the contour and the heterogeneity simultaneously. The inter- and intraobserver agreement ranged from moderate to good. We conclude that on the outlet view, modifications in the superior contour and heterogeneity of the supraspinatus muscle radiodensity suggest a full-thickness tear. Received: 6 December 1999 Revision requested: 6 March 2000 Revision received: 5 June 2000 Accepted: 4 October 2000  相似文献   
35.
Available data on clinical presentation and mortality of coronavirus disease-2019 (COVID-19) in heart transplant (HT) recipients remain limited. We report a case series of laboratory-confirmed COVID-19 in 39 HT recipients from 3 French heart transplant centres (mean age 54.4 ± 14.8 years; 66.7% males). Hospital admission was required for 35 (89.7%) cases including 14/39 (35.9%) cases being admitted in intensive care unit. Immunosuppressive medications were reduced or discontinued in 74.4% of the patients. After a median follow-up of 54 (19–80) days, death and death or need for mechanical ventilation occurred in 25.6% and 33.3% of patients, respectively. Elevated C-reactive protein and lung involvement ≥50% on chest computed tomography (CT) at admission were associated with an increased risk of death or need for mechanical ventilation. Mortality rate from March to June in the entire 3-centre HT recipient cohort was 56% higher in 2020 compared to the time-matched 2019 cohort (2% vs. 1.28%, P = 0.15). In a meta-analysis including 4 studies, pre-existing diabetes mellitus (OR 3.60, 95% CI 1.43–9.06, I2 = 0%, P = 0.006) and chronic kidney disease stage III or higher (OR 3.79, 95% CI 1.39–10.31, I2 = 0%, P = 0.009) were associated with increased mortality. These findings highlight the aggressive clinical course of COVID-19 in HT recipients.  相似文献   
36.
The mechanical properties of dentin are largely determined by the intertubular dentin matrix, which is a complex composite of type I collagen fibers and a carbonate-rich apatite mineral phase. We performed a small angle X-ray scattering (SAXS) study on fully mineralized human dentin to quantify this fiber/mineral composite architecture from the nanoscopic through continuum length scales. The SAXS results were consistent with nucleation and growth of the apatite phase within periodic gaps in the collagen fibers. These mineralized fibers were perpendicular to the dentinal tubules and parallel with the mineralization growth front. Within the plane of the mineralization front, the mineralized collagen fibers were isotropic near the pulp, but became mildly anisotropic in the mid-dentin. Analysis of the data also indicated that near the pulp the mineral crystallites were approximately needle-like, and progressed to a more plate-like shape near the dentino-enamel junction. The thickness of these crystallites, approximately 5 nm, did not vary significantly with position in the tooth. These results were considered within the context of dentinogenesis and maturation.  相似文献   
37.

BACKGROUND

Enhancing patient-centered care and shared decision making (SDM) has become a national priority as a means of engaging patients in their care, improving treatment adherence, and enhancing health outcomes. Relatively little is known about the healthcare experiences or shared decision making among racial/ethnic minorities who also identify as being LGBT. The purpose of this paper is to understand how race, sexual orientation and gender identity can simultaneously influence SDM among African-American LGBT persons, and to propose a model of SDM between such patients and their healthcare providers.

METHODS

We reviewed key constructs necessary for understanding SDM among African-American LGBT persons, which guided our systematic literature review. Eligible studies for the review included English-language studies of adults (≥ 19 y/o) in North America, with a focus on LGBT persons who were African-American/black (i.e., > 50 % of the study population) or included sub-analyses by sexual orientation/gender identity and race. We searched PubMed, CINAHL, ProQuest Dissertations & Theses, PsycINFO, and Scopus databases using MESH terms and keywords related to shared decision making, communication quality (e.g., trust, bias), African-Americans, and LGBT persons. Additional references were identified by manual reviews of peer-reviewed journals’ tables of contents and key papers’ references.

RESULTS

We identified 2298 abstracts, three of which met the inclusion criteria. Of the included studies, one was cross-sectional and two were qualitative; one study involved transgender women (91 % minorities, 65 % of whom were African-Americans), and two involved African-American men who have sex with men (MSM). All of the studies focused on HIV infection. Sexual orientation and gender identity were patient-reported factors that negatively impacted patient/provider relationships and SDM. Engaging in SDM helped some patients overcome normative beliefs about clinical encounters. In this paper, we present a conceptual model for understanding SDM in African-American LGBT persons, wherein multiple systems of social stratification (e.g., race, gender, sexual orientation) influence patient and provider perceptions, behaviors, and shared decision making.

DISCUSSION

Few studies exist that explore SDM among African-American LGBT persons, and no interventions were identified in our systematic review. Thus, we are unable to draw conclusions about the effect size of SDM among this population on health outcomes. Qualitative work suggests that race, sexual orientation and gender work collectively to enhance perceptions of discrimination and decrease SDM among African-American LGBT persons. More research is needed to obtain a comprehensive understanding of shared decision making and subsequent health outcomes among African-Americans along the entire spectrum of gender and sexual orientation.
  相似文献   
38.
Hepatocytes are hypothesized to continuallystream from the portal tract to the terminal hepaticvein. By this model, when a cell divides, one of itsprogeny replaces the dividing ancestor and the other is displaced into a more remote location. Thepresent experiment aims to demonstrate thathypothyroidism affects liver cell turnover. Thirty maleadult rats were divided into two groups. One receivedmethimazole for two weeks and the other served as control.Each rat was injected intraperitoneally with 18.5 KBq[3H]thymidine/g body weight. Rats were killedafter 1 hr and two and four weeks. Autoradiography was done. The distance of the labeled cells fromthe portal tract was measured. The mean TSH levels ofthe methimazole-treated group and controls were 1.45 and0.25 mM/liter, respectively (P < 0.01). Hepatocyte streaming was lower in hypothyroid (1.8m/day) than in untreated rats (2.5 m/day) (P< 0.01). The respective labeling indices 1 hr afterlabeling were 0.9% and 1.24% (P < 0.05). We concludethat hypothyroidism diminishes hepatocyte and littoral cellturnover and slows down their streaming.  相似文献   
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