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1.

Purpose

To assess the time course of optical quality and intraocular scattering in relation to visual acuity after femtosecond lenticule extraction (FLEx) for the correction of myopia.

Methods

This study evaluated 36 eyes of 36 patients with spherical equivalents of −4.38±1.53 D [mean ± standard deviation] who underwent FLEx. Before surgery, and 1 week and 1, 3 and 6 months after surgery, we assessed the modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and OQAS values (OVs), using a double-pass instrument. We also investigated the relationship of the OSI with corrected distance visual acuity (CDVA) preoperatively and postoperatively.

Results

The mean changes in MTF cutoff frequency, Strehl ratio, OSI, OV100%, OV20%, and OV9% preoperatively and 6 months postoperatively were −5.51±15.01, −0.03±0.07, 0.35±0.83, −0.17±0.48, −0.14±0.38, and −0.09±0.22, respectively. We found no significant preoperative correlation between the OSI and logMAR CDVA (Spearman rank correlation coefficient r = 0.068, p = 0.69), and modest, but significant correlations 1 week and 1, 3, and 6 months postoperatively (r = 0.572, r = 0.562, r = 0.542, r = 0.540, p<0.001, respectively).

Conclusions

FLEx induced a transient decrease in optical quality in association with an increase in intraocular scattering in the early postoperative period, possibly due to mild interface haze formation, but gradually recovered with time. It is suggested that this transient degradation in optical quality related to an increase in the intraocular scattering may result in a slight delay of CDVA recovery in the early postoperative period.  相似文献   

2.

Purpose

To evaluate intra- and intersession repeatability of objective optical quality and intraocular scattering measurements with a double-pass system in children.

Methods

Forty-two eyes of 42 children were included in the study. An optical quality analysis system (OQAS) was used to measure optical quality parameters, including modulation transfer function cutoff frequency (MTFcutoff), Strehl ratio (SR), OQAS values (OV) at 3 different contrasts and objective scatter index (OSI). Three measurement sessions with 10-min intervals were operated by the same technician, and in each session four consecutive measurements were obtained.

Results

Mean values for MTFcutoff, SR and OSI were 46.85 ± 7.45cpd, 0.27 ± 0.06 and 0.34 ± 0.22 respectively. 1) The intraclass correlation coefficients were ranged from 0.89 to 0.97 and coefficients of variation from 0.06 to 0.16 for all the parameters in the first session; the relative repeatability were 11.1% (MTFcutoff), 22.5% (SR), 10.9% (OV100%), 16.6% (OV2%), 22.4% (OV9%) and 56.3% (OSI). Similar results were found in the second and third sessions. 2) Bland-Altman analysis showed that narrow 95% confidence intervals (compared between the first and second sessions) ranged from -5.42 to 5.28 (MTFcutoff), -0.05 to 0.07 (SR), -0.18 to 0.18 (OV100%), -0.26 to 0.29 (OV20%), -0.33 to 0.39 (OV9%) and -0.11 to 0.09 (OSI); the comparison between any two of the three sessions showed similar results.

Conclusion

Measurements of optical quality and intraocular scattering in children by the double-pass system showed good intra- and intersession repeatability. Retinal image quality is high and intraocular scattering is low in children.  相似文献   

3.

Purpose

To evaluate the factors affecting the area under the log contrast sensitivity function (AULCSF) in healthy myopic eyes.

Methods

We retrospectively examined 201 eyes of 201 consecutive subjects (age, 31.8±7.4 years (mean ± standard deviation)) with myopic refractive errors of −1.25 to −8.25 diopters (D). From the contrast sensitivity data, the area under the log contrast sensitivity function (AULCSF) was calculated. Stepwise multiple regression analysis was used to assess the factors affecting the AULCSF.

Results

The mean AULSCF was 1.09±0.09 (0.89 to 1.55). Explanatory variables relevant to the AULCSF were, in order of influence, the objective scattering index (OSI) (p = 0.018, partial regression coefficient B = –0.032) and logMAR CDVA (p = 0.022, B = –0.209) (adjusted R2 = 0.231). No significant correlation was seen with other clinical factors such as gender, manifest refraction, pupil size, lens density, corneal HOAs, or ocular HOAs.

Conclusions

Although the great majority of the variance remains unexplained, eyes with lower OSI and better CDVA are more predisposed to show higher contrast sensitivity function. These results indicate that not only CDVA but also intraocular forward scattering may play some role in predicting the contrast sensitivity function in myopic subjects.  相似文献   

4.

Purpose

The present study determined the association between body fluid variation and the development of acute mountain sickness (AMS) in adults.

Methods

Forty-three healthy participants (26 males and 17 females, age: 26±6 yr, height: 174±9 cm, weight: 68±12 kg) were passively exposed at a FiO2 of 12.6% (simulated altitude hypoxia of 4500 m, PiO2 = 83.9 mmHg) for 12-h. AMS severity was assessed using the Lake Louise Score (LLS). Food and drink intakes were consumed ad libitum and measured; all urine was collected. Before and after the 12-h exposure, body weight and plasma osmolality were measured and whole-body bioimpedance analysis was performed.

Results

The overall AMS incidence was 43% (38% males, 50% females). Participants who developed AMS showed lower fluid losses (3.0±0.9 vs. 4.5±2.0 ml/kg/h, p = 0.002), a higher fluid retention (1.9±1.5 vs. 0.6±0.8 ml/kg/h, p = 0.022), greater plasma osmolality decreases (−7±7 vs. −2±5 mOsm/kg, p = 0.028) and a larger plasma volume expansion (11±10 vs. 1±15%, p = 0.041) compared to participants not developing AMS. Net water balance (fluid intake – fluid loss) and the amount of fluid loss were strong predictors whether getting sick or not (Nagelkerkes r2 = 0.532). The LLS score was related to net water balance (r = 0.358, p = 0.018), changes in plasma osmolality (r = −0.325, p = 0.033) and sodium concentration (r = −0.305, p = 0.047). Changes in the impedance vector length were related to weight changes (r = −0.550, p<0.001), fluid intake (r = −0.533, p<0.001) and net water balance (r = −0.590, p<0.001).

Conclusions

Participants developing AMS within 12 hours showed a positive net water balance due to low fluid loss. Thus measures to avoid excess fluid retention are likely to reduce AMS symptoms.  相似文献   

5.

Background

Health related quality of life (HRQoL) is an important dimension of individuals'' well-being, and especially in chronic diseases like diabetes and hypertension. The objective of this study was to evaluate the contributions of disease process, comorbidities, medication or awareness of the disease to HRQoL in diabetes mellitus, hypertension and dyslipidemia.

Methods

This was a cross-sectional study of 3514 respondents from the general community in Singapore, assessed for HRQoL, disease and comorbid conditions through self-report, clinical and laboratory investigations. HRQoL was assessed using SF-36 health survey version 2. For each condition, participants were categorized as having 1) no disease, 2) undiagnosed, 3) diagnosed, not taking medication, and 4) diagnosed, taking medication. Analysis used one-way ANOVA and multiple linear regression.

Results

Diagnosed disease was associated with lower physical health component summary (PCS) scores across all three conditions. After adjustment for comorbidities, this association remained significant only for those not on medication in diabetes (−2.7±1.2 points, p = 0.03) and dyslipidemia (−1.3±0.4 points, p = 0.003). Diagnosed hypertension (no medication −2.6±0.9 points, p = 0.002; medication −1.4±0.5 points, p = 0.004) and dyslipidemia (no medication −0.9±0.4 points, p = 0.03; medication −1.9±0.5 points, p<0.001) were associated with lower mental health component summary (MCS) scores. Undiagnosed disease was associated with higher MCS in diabetes (2.4±1.0 points, p = 0.01) and dyslipidemia (0.8±0.4 points, p = 0.045), and PCS in hypertension (1.2±0.4 points, p = 0.004).

Conclusions

Disease awareness was associated with lower HRQoL across the diseases studied, with PCS associations partially mediated by comorbidities. Equally importantly, undiagnosed disease was not associated with HRQoL deficits, which may partly explain why these individuals do not seek medical care.  相似文献   

6.

Background

To decrease the risk of postoperative complication, improving general and pulmonary conditioning preoperatively should be considered essential for patients scheduled to undergo lung surgery.

Objective

The aim of this study is to develop a short-term beneficial program of preoperative pulmonary rehabilitation for lung cancer patients.

Methods

From June 2009, comprehensive preoperative pulmonary rehabilitation (CHPR) including intensive nutritional support was performed prospectively using a multidisciplinary team-based approach. Postoperative complication rate and the transitions of pulmonary function in CHPR were compared with historical data of conventional preoperative pulmonary rehabilitation (CVPR) conducted since June 2006. The study population was limited to patients who underwent standard lobectomy.

Results

Postoperative complication rate in the CVPR (n = 29) and CHPR (n = 21) were 48.3% and 28.6% (p = 0.2428), respectively. Those in patients with Charlson Comorbidity Index scores ≥2 were 68.8% (n = 16) and 27.3% (n = 11), respectively (p = 0.0341) and those in patients with preoperative risk score in Estimation of Physiologic Ability and Surgical Stress scores >0.3 were 57.9% (n = 19) and 21.4% (n = 14), respectively (p = 0.0362). Vital capacities of pre- and post intervention before surgery in the CHPR group were 2.63±0.65 L and 2.75±0.63 L (p = 0.0043), respectively; however, their transition in the CVPR group was not statistically significant (p = 0.6815). Forced expiratory volumes in one second of pre- and post intervention before surgery in the CHPR group were 1.73±0.46 L and 1.87±0.46 L (p = 0.0012), respectively; however, their transition in the CVPR group was not statistically significant (p = 0.6424).

Conclusions

CHPR appeared to be a beneficial and effective short-term preoperative rehabilitation protocol, especially in patients with poor preoperative conditions.  相似文献   

7.

Objectives

Patients with coronary ectasia (CE) usually have coexisting coronary stenosis resulting in myoischemia. Coronary collateral plays an important role in protecting myocardium from ischemia and reducing cardiovascular events. However, limited studies investigate the role of CE in coronary collaterals development.

Methods

We evaluated 1020 consecutive patients undergoing coronary angiography and 552 patients with significant coronary artery disease (SCAD), defined as diameter stenosis more than 70%, were finally analyzed. CE is defined as the ectatic diameter 1.5 times larger than adjacent reference segment. Rentrop collateral score was used to classify patients into poor (grades 0 and 1) or good (grades 2 and 3) collateral group.

Results

73 patients (13.2%) had CE lesions which were most located in the right coronary artery (53.4%). Patients with CE had a lower incidence of diabetes (43.8% vs 30.1%, p = 0.03), higher body mass index (25.4±3.5 vs 26.7±4.6, p = 0.027) and poorer coronary collateral (58.2% vs 71.2%, p = 0.040). Patients with poor collateral (n = 331) had a higher incidence of CE (15.7% vs 9.5%, p = 0.040) and fewer diseased vessels numbers (1.96±0.84 vs 2.48±0.69, p<0.001). Multivariate analysis showed diabetes (odd ratio (OR) 0.630, p = 0.026), CE (OR = 0.544, p = 0.048), and number of diseased vessels (OR = 2.488, p<0.001) were significant predictors of coronary collaterals development.

Conclusion

The presence of CE was associated with poorer coronary collateral development in patients with SCAD.  相似文献   

8.

Background

The prevalence of obesity is rising. Obesity can lead to cardiovascular and ventilatory complications through multiple mechanisms. Cardiac and pulmonary function in asymptomatic subjects and the effect of structured dietary programs on cardiac and pulmonary function is unclear.

Objective

To determine lung and cardiac function in asymptomatic obese adults and to evaluate whether weight loss positively affects functional parameters.

Methods

We prospectively evaluated bodyplethysmographic and echocardiographic data in asymptomatic subjects undergoing a structured one-year weight reduction program.

Results

74 subjects (32 male, 42 female; mean age 42±12 years) with an average BMI 42.5±7.9, body weight 123.7±24.9 kg were enrolled. Body weight correlated negatively with vital capacity (R = −0.42, p<0.001), FEV1 (R = −0.497, p<0.001) and positively with P 0.1 (R = 0.32, p = 0.02) and myocardial mass (R = 0.419, p = 0.002). After 4 months the study subjects had significantly reduced their body weight (−26.0±11.8 kg) and BMI (−8.9±3.8) associated with a significant improvement of lung function (absolute changes: vital capacity +5.5±7.5% pred., p<0.001; FEV1+9.8±8.3% pred., p<0.001, ITGV+16.4±16.0% pred., p<0.001, SR tot −17.4±41.5% pred., p<0.01). Moreover, P0.1/Pimax decreased to 47.7% (p<0.01) indicating a decreased respiratory load. The change of FEV1 correlated significantly with the change of body weight (R = −0.31, p = 0.03). Echocardiography demonstrated reduced myocardial wall thickness (−0.08±0.2 cm, p = 0.02) and improved left ventricular myocardial performance index (−0.16±0.35, p = 0.02). Mitral annular plane systolic excursion (+0.14, p = 0.03) and pulmonary outflow acceleration time (AT +26.65±41.3 ms, p = 0.001) increased.

Conclusion

Even in asymptomatic individuals obesity is associated with abnormalities in pulmonary and cardiac function and increased myocardial mass. All the abnormalities can be reversed by a weight reduction program.  相似文献   

9.

Background

The cardiovascular impact of cocaine use in otherwise healthy individuals who consider themselves ‘social’ users is not well established.

Methods/Results

Twenty regular cocaine users and 20 control subjects were recruited by word-of-mouth. Cardiovascular magnetic resonance was performed to assess cardiac and vascular structure and function. Cocaine users had higher systolic blood pressure compared to non-users (134±11 vs 126±11 mmHg, p = 0.036), a finding independent of age, body surface area, smoking and alcohol consumption. Cocaine use was associated with increased arterial stiffness - reflected by reduced aortic compliance (1.3±0.2 vs 1.7±0.5 cm2×10−2.mmHg−1, p = 0.004), decreased distensibility (3.8±0.9 vs 5.1±1.4 mmHg−1.10−3, p = 0.001), increased stiffness index (2.6±0.6 vs 2.1±0.6, p = 0.005), and higher pulse wave velocity (5.1±0.6 vs 4.4±0.6 m.s−1, p = 0.001). This change in aortic stiffness was independent of vessel wall thickness. Left ventricular mass was 18% higher in cocaine users (124±25 vs 105±16 g, p = 0.01), a finding that was independent of body surface area, and left atrial diameter was larger in the user group than controls (3.8±0.6 vs 3.5±0.3 cm, p = 0.04). The increased left ventricular mass, systolic blood pressure and vascular stiffness measures were all associated with duration and/or frequency of cocaine use. No late gadolinium enhancement or segmental wall motion abnormalities were seen in any of the subjects.

Conclusions

Compared with the non-user control cohort, cocaine users had increased aortic stiffness and systolic blood pressure, associated with greater left ventricular mass. These measures are all well known risk factors for premature cardiovascular events, highlighting the dangers of cocaine use, even in a ‘social’ setting, and have important public health implications.  相似文献   

10.

Objectives

Our objective is to test the hypothesis that coronary endothelial function (CorEndoFx) does not change with repeated isometric handgrip (IHG) stress in CAD patients or healthy subjects.

Background

Coronary responses to endothelial-dependent stressors are important measures of vascular risk that can change in response to environmental stimuli or pharmacologic interventions. The evaluation of the effect of an acute intervention on endothelial response is only valid if the measurement does not change significantly in the short term under normal conditions. Using 3.0 Tesla (T) MRI, we non-invasively compared two coronary artery endothelial function measurements separated by a ten minute interval in healthy subjects and patients with coronary artery disease (CAD).

Methods

Twenty healthy adult subjects and 12 CAD patients were studied on a commercial 3.0 T whole-body MR imaging system. Coronary cross-sectional area (CSA), peak diastolic coronary flow velocity (PDFV) and blood-flow were quantified before and during continuous IHG stress, an endothelial-dependent stressor. The IHG exercise with imaging was repeated after a 10 minute recovery period.

Results

In healthy adults, coronary artery CSA changes and blood-flow increases did not differ between the first and second stresses (mean % change ±SEM, first vs. second stress CSA: 14.8%±3.3% vs. 17.8%±3.6%, p = 0.24; PDFV: 27.5%±4.9% vs. 24.2%±4.5%, p = 0.54; blood-flow: 44.3%±8.3 vs. 44.8%±8.1, p = 0.84). The coronary vasoreactive responses in the CAD patients also did not differ between the first and second stresses (mean % change ±SEM, first stress vs. second stress: CSA: −6.4%±2.0% vs. −5.0%±2.4%, p = 0.22; PDFV: −4.0%±4.6% vs. −4.2%±5.3%, p = 0.83; blood-flow: −9.7%±5.1% vs. −8.7%±6.3%, p = 0.38).

Conclusion

MRI measures of CorEndoFx are unchanged during repeated isometric handgrip exercise tests in CAD patients and healthy adults. These findings demonstrate the repeatability of noninvasive 3T MRI assessment of CorEndoFx and support its use in future studies designed to determine the effects of acute interventions on coronary vasoreactivity.  相似文献   

11.

Background

It has been hypothesized that obese and reduced-obese individuals have decreased oxidative capacity, which contributes to weight gain and regain. Recent data have challenged this concept.

Objective

To determine (1) whether total and dietary fat oxidation are decreased in obese and reduced-obese adults compared to lean but increase in response to an acute exercise bout and (2) whether regular physical activity attenuates these metabolic alterations.

Design

We measured 24-hr total (whole-room calorimetry) and dietary fat (14C-oleate) oxidation in Sedentary Lean (BMI = 21.5±1.6; n = 10), Sedentary Obese (BMI = 33.6±2.5; n = 9), Sedentary Reduced-Obese (RED-SED; BMI = 26.9±3.7; n = 7) and in Physically Active Reduced-Obese (RED-EX; BMI = 27.3±2.8; n = 12) men and women with or without an acute exercise bout where energy expended during exercise was not replaced.

Results

Although Red-SED and Red-EX had a similar level of fatness, aerobic capacity and metabolic profiles were better in Red-EX only compared to Obese subjects. No significant between-group differences were seen in 24-hr respiratory quotient (RQ, Lean: 0.831±0.044, Obese: 0.852±0.023, Red-SED: 0.864±0.037, Red-EX: 0.842±0.039), total and dietary fat oxidation. A single bout of exercise increased total (+27.8%, p<0.0001) and dietary (+6.6%, p = 0.048) fat oxidation across groups. Although exercise did not impact RQ during the day, it decreased RQ during sleep (p = 0.01) in all groups. Red-EX oxidized more fat overnight than Red-SED subjects under both resting (p = 0.036) and negative energy balance (p = 0.003) conditions, even after adjustment for fat-free mass.

Conclusion

Obese and reduced-obese individuals oxidize as much fat as lean both under eucaloric and negative energy balance conditions, which does not support the hypothesis of reduced oxidative capacity in these groups. Reduced-obese individuals who exercise regularly have markers of metabolic health similar to those seen in lean adults. Both the acute and chronic effects of exercise were primarily observed at night suggesting an important role of sleep in the regulation of lipid metabolism.  相似文献   

12.
13.
14.

Objectives

We assessed the value of speckle tracking imaging performed early after a first ST-segment elevation myocardial infarction (STEMI) in order to predict infarct size and functional recovery at 3-month follow-up.

Methods

44 patients with STEMI who underwent revascularization within 12 h of symptom onset were prospectively enrolled. Echocardiography was performed 3.9±1.2 days after myocardial reperfusion, assessing circumferential (CGS), radial (RGS), and longitudinal global (GLS) strains. Late gadolinium-enhanced cardiac magnetic imaging (CMR), for assessing cardiac function, infarct size, and microvascular obstruction (MVO), was conducted 5.6±2.5 days and 99.4±4.6 days after myocardial reperfusion.

Results

GLS was evaluable in 97% of the patients, while CGS and RGS could be assessed in 85%. Infarct size significantly correlated with GLS (R = 0.601, p<0.001), RGS (R = −0.405, p = 0.010), CGS (R = 0.526, p = 0.001), ejection fraction (R = −0.699, p<0.001), wall motion score index (WMSI) (R = 0.539, p = 0.001), and left atrial volume (R = 0.510, p<0.001). Baseline ejection fraction and GLS were independent predictors of 3-month infarct size. MVO mass significantly correlated with GLS (R = 0.376, p = 0.010), WMSI (R = 0.387, p = 0.011), and ejection fraction (R = −0.389, p = 0.011). In multivariate analysis, GLS was the only independent predictor of MVO mass (p = 0.015). Longitudinal strain >−6.0% within the infarcted area exhibited 96% specificity and 61% sensitivity for predicting the persistence of akinesia (≥3 segments) at 3-month follow-up.

Conclusions

Speckle-tracking strain imaging performed early after a STEMI is easy-to-use as a marker for persistent akinetic territories at 3 months. In addition, GLS correlated significantly with MVO and final infarct size, both parameters being relevant post-MI prognostic factors, usually obtained via CMR.  相似文献   

15.
16.
17.

Background

Matrix metalloproteinases play a role in regulating cardiac remodeling. We previously reported an association between tissue inhibitor of metalloproteinase 2 (TIMP-2) expression and mitral valve (MV) disease. However, the determinants and prognostic value of mitral TIMP2 after MV surgery are unknown.

Methods

This retrospective study of 164 patients after MV surgery in a tertiary medical center in Taiwan assessed mitral TIMP2 on a semiquantitative scale (0–2) by immunohistochemical staining. The primary endpoints were the composite of cardiovascular death and heart failure admission.

Results

Mean age was 50.4±13.7 years. After a mean follow-up period of 101±59 months, primary endpoints had occurred in 25 (15.2%) subjects. Patients with and without primary endpoint events significantly differed in terms of age (56.6±14.4 vs. 49.2±13.4 years, respectively; p = 0.013) and left ventricular end-systolic diameter (LVESD) (39.7±8.2 vs. 35.5±7.5 mm, p = 0.010) at surgery. The TIMP2 had a significant dose-dependent association with development of a primary endpoint (p = 0.002). Kaplan–Meier analysis showed that TIMP2 expression has a significant positive association with primary endpoint-free survival (log-rank test; p = 0.004). Cox regression analysis showed that independent predictors of primary endpoints were TIMP2 (hazard ratio [HR] 0.28; 95% confidence interval [CI] 0.12–0.65; p = 0.003), age (HR 1.05; 95% CI 1.02–1.09; p = 0.003) and LVESD (HR 1.05; 95% CI 1.01–1.10; p = 0.020).

Conclusions

The lack of mitral TIMP2 expression is associated with increases in cardiovascular death and heart failure following MV surgery.  相似文献   

18.

Background

Matrix metalloproteinase-9 (MMP-9) is an emerging biomarker for several disease conditions, where white blood cell (WBC) count is also elevated. In this study, we examined the relationship between MMP-9 and WBC levels in apparently healthy smoking and non-smoking human subjects.

Methods

We conducted a cross-sectional study to assess the relationship of serum MMP-9 with WBC in 383 men and 356 women. Next, we divided the male population (women do not smoke in this population) into three groups: never (n = 243), current (n = 76) and former (n = 64) smokers and compared the group differences in MMP-9 and WBC levels and their correlations within each group.

Results

Circulating MMP-9 and WBC count are significantly correlated in men (R2 = 0.13, p<0.001) and women (R2 = 0.19, p<0.001). After stratification by smoking status, MMP-9 level was significantly higher in current smokers (mean ± SE; 663.3±43.4 ng/ml), compared to never (529.7±20.6) and former smokers (568±39.3). WBC count was changed in a similar pattern. Meanwhile, the relationship became stronger in current smokers with increased correlation coefficient of r = 0.45 or R2 = 0.21 (p<0.001) and steeper slope of ß = 1.16±0.30 (p<0.001) in current smokers, compared to r = 0.26 or R2 = 0.07 (p<0.001) and ß = 0.34±0.10 (p<0.001) in never smokers.

Conclusions

WBC count accounts for 13% and 19% of MMP-9 variance in men and women, respectively. In non-smoking men, WBC count accounts for 7% of MMP-9 variance, but in smoking subjects, it accounts for up to 21% of MMP-9 variance. Thus, we have discovered a previously unrecognized correlation between the circulating MMP-9 and WBC levels in humans.  相似文献   

19.

Objective

Vitamin D deficiency is common and associated with increased cardiovascular disease (CVD) risk. Pulse wave velocity (PWV) is a marker of vascular stiffness associated with CVD. We hypothesized that Vitamin D (25 (OH) D) levels would be inversely associated with PWV in youth with and without type 1 diabetes (T1D).

Study Design

Comparisons were made between adolescents with T1D (n = 211; age = 17.5±2.3 years; diabetes duration = 10.9±3.2 years; A1c = 9.1±1.7%) and non-DM controls (n = 67; age = 16.9±1.9 years). PWV was measured in the carotid-femoral segment (Sphygmocor Vx, AtCor Medical, Lisle, IL).

Results

Vitamin D levels were similar in adolescents with T1D and controls (27.7±0.7 v. 26.0±1.3 ng/ml; p = 0.26). Vitamin D was significantly inversely associated with PWV after adjusting for age, sex, quarter of the year, and race-ethnicity in adolescents with T1D (beta  = −0.01±0.004, p = 0.02) but not in the non-DM adolescents (beta  = −0.008±0.008, p = 0.32). Vitamin D remained significantly associated with PWV after additionally adjusting for hs-CRP in adolescents with T1D (−0.01±0.004, p = 0.01). After adjusting for BMI z-score, lipids, or blood pressure, the relationship of Vitamin D with PWV was not significant.

Conclusions

Vitamin D levels were inversely associated with PWV in adolescents with T1D, but not independently of BMI, lipids, or blood pressure. Our data contrast with other reports and suggest further research is indicated to determine if Vitamin D supplementation would be beneficial to lower CVD risk in adolescents with T1D with vitamin D insufficiency or deficiency.  相似文献   

20.

Purpose

To compare in young and old rats longitudinal measurements of retinal nerve fiber layer thickness (RNFLT) and axonal transport 3-weeks after chronic IOP elevation.

Method

IOP was elevated unilaterally in 2- and 9.5-month-old Brown-Norway rats by intracameral injections of magnetic microbeads. RNFLT was measured by spectral domain optical coherence tomography. Anterograde axonal transport was assessed from confocal scanning laser ophthalmolscopy of superior colliculi (SC) after bilateral intravitreal injections of cholera toxin-B-488. Optic nerve sections were graded for damage.

Results

Mean IOP was elevated in both groups (young 37, old 38 mmHg, p = 0.95). RNFL in young rats exhibited 10% thickening at 1-week (50.9±8.1 µm, p<0.05) vs. baseline (46.4±2.4 µm), then 7% thinning at 2-weeks (43.0±7.2 µm, p>0.05) and 3-weeks (43.5±4.4 µm, p>0.05), representing 20% loss of dynamic range. RNFLT in old rats showed no significant change at 1-week (44.9±4.1 µm) vs. baseline (49.2±5.3 µm), but progression to 22% thinning at 2-weeks (38.0±3.7 µm, p<0.01) and 3-weeks (40.0±6.6 µm, p<0.05), representing 59% loss of dynamic range. Relative SC fluorescence intensity was reduced in both groups (p<0.001), representing 77–80% loss of dynamic range and a severe transport deficit. Optic nerves showed 75–95% damage (p<0.001). There was greater RNFL thinning in old rats (p<0.05), despite equivalent IOP insult, transport deficit and nerve damage between age groups (all p>0.05).

Conclusion

Chronic IOP elevation resulted in severely disrupted axonal transport and optic nerve axon damage in all rats, associated with mild RNFL loss in young rats but a moderate RNFL loss in old rats despite the similar IOP insult. Hence, the glaucomatous injury response within the RNFL depends on age.  相似文献   

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