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81.
In the setting of myocardial ischemia, recovery of myocardial function by revascularization procedures depends on the extent of coronary disease and myocardial scar burden. Currently, computed tomographic (CT) imaging offers superior evaluation of coronary lesions but lacks the capability to measure the transmural extent of myocardial scar. Our work focuses on determining if collagen-targeting gold nanoparticles (AuNPs) can effectively target myocardial scar and provide adequate contrast for CT imaging. AuNPs were coated with a collagen-homing peptide, collagen adhesin (CNA35). Myocardial scar was created in mice by occlusion/reperfusion of the left anterior descending coronary artery. Thirty days later, un-gated CT imaging was performed. Over 6 h, CNA35-AuNPs provided uniform and prolonged opacification of the vascular structures (100-130 HU). In mice with larger scar burden, focal contrast enhancement was detected in the myocardium, which was not apparent within that of control mice. Histological staining confirmed myocardial scar formation and accumulation of AuNPs.From the Clinical EditorThis team of investigators presents a collagen-targeting gold nanoparticle-based approach that enables the imaging of myocardial scars via CT scans in a rodent model. This information would enable clinicians to judge the recovery potential of myocardium more accurately than the current CT-scan based approaches.  相似文献   
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BackgroundThe aim of this study was to evaluate the long-term effects of laparoscopic sleeve gastrectomy (LSG) on type 2 diabetes mellitus (T2DM) and other related co-morbidities in severely obese patients.MethodsFrom May 2003 to July 2008, 33 morbidly obese diabetic patients (20 with body mass index [BMI]>50 kg/m2) underwent LSG. A total of 23 females and 10 males participated, with a mean age of 49.3±8 years, mean preoperative BMI of 52.1±8.5 kg/m2, mean fasting plasma glucose (FPG) of 143.2±47.9 mg/dL, mean glycosylated hemoglobin (HbA1c) of 7.3%±1.4%, and a mean T2DM duration of 7 years. All patients had a 36-month follow-up, and 13 had a 60-month follow-up.ResultsTwenty-nine patients (87.8%) discontinued antidiabetic medications 3 months after LSG, (mean BMI of 42.8±7.8 kg/m2; FPG of 104.5±22.1 mg/dL; HbA1c of 5.3%±.4%). At 36 months, 22 of 26 LSG patients (84.6%) had normal FPG and HbA1c values without antidiabetic therapy. At the 60-month follow-up, 10 of 13 patients (76.9%) had normal FPG and HbA1c values without antidiabetic therapy. The Framingham risk score decreased significantly from 9.7% preoperatively to 4.7% postoperatively. No new diabetic retinopathy occurred during the whole period of observation.ConclusionsThis study confirms the efficacy of LSG in the treatment of T2DM and indicates that, at both 36- and 60-month follow-ups, LSG can provide a significant percentage of treated patients with a prolonged remission of T2DM, with diminished cardiac risk factors and no development of diabetic retinopathy. These results compare favorably with those reported after standard medical therapy.  相似文献   
84.
Phototherapy using coherent light (lasers) and non-coherent light (light-emitting diodes (LEDs)) has been investigated for the purpose of biomodulation in biological tissues. Several effects can be expected, including pain moderation, biostimulation of cellular tropism, anti-inflammatory effects, regular circulatory stimulation, and tissue repair. The aim of this study was to evaluate the effect of LED (λ945 ± 20 nm, 48 mW) therapy on the regeneration process in femoral lesions of rats (Wistar). Seven irradiation sessions were held, with a 48-h interval between sessions. The animals were euthanised 14, 21, and 28 days after surgery. Bone samples were analysed by histomorphometry, micro X-ray fluorescence spectroscopy, scanning electron microscopy, and optical densitometry. The results demonstrated the effective positive influence of low-intensity LED therapy using the near-infrared region on the tissue repair process in diabetic animals, especially in the early stages of repair (14 and 21 days after surgery). It can be concluded that LED therapy positively influences bone formation in the early stages of the bone repair process in non-diabetic and diabetic animals, without causing changes in the optical density and volume of tissue in the final stages. No influence of LED therapy was observed on the percentage of calcium, percentage of phosphorus, Ca/P ratio, or optical mineral density in non-diabetic animals. However, increased mineral concentration was evident in the diabetic animals treated with the LED during the repair process.  相似文献   
85.
Our study assessed acoustic radiation force impulse (ARFI) reproducibility and the factors influencing it. The intra- and interoperator reproducibility were studied in 33 and 58 patients, respectively. Intraclass correlation coefficient (ICC) was used to assess ARFI reproducibility. The overall intraoperator agreement was better than the interoperator one: ICC 0.90 vs. ICC 0.81. The correlation of repeated ARFI measurements was higher, but not significantly so, in cases in which intraoperator reproducibility was assessed compared with the ones in which interoperator reproducibility was studied: r = 0.848 vs. r = 0.694 (p = 0.08). For both intra- and interoperator reproducibility, the ICCs were smaller in women vs. men (0.88 vs. 0.91 and 0.67 vs. 0.86, respectively), in patients with high body mass index (BMI) ≥25 kg/m2 vs. <25 kg/m2 (0.88 vs. 0.91 and 0.79 vs. 0.82, respectively), in patients with ascites vs. no ascites (0.80 vs. 0.93 and 0.78 vs. 0.84, respectively) and in noncirrhotic vs. cirrhotic patients (0.77 vs. 0.82 and 0.70 vs. 0.83, respectively).  相似文献   
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In 83 elderly breast cancer patients, oestrogen and progesterone receptors (ER, PgR), pS2 and cathepsin D (CathD) were evaluated for their possible prognostic role on disease-free survival (DFS). The biomarkers were determined on the same cytosol by using immunoradiometric assays, and the variables were considered on a continuous scale. Univariate analysis indicated a linear relationship between logarithmic hazard ratio (log(HR)) and the log(ER) and log(PgR) concentration, but a non-linear relationship between log(HR) and CathD. As regards pS2, there was no evidence of a relationship with log(HR). In multivariate analysis, log(ER) content did not have a significant prognostic role, whereas log(PgR) retained a significant prognostic role. As regards the predictive ability, log(PgR) was the best discriminator of outcome followed by CathD, whereas the contribution of log(ER) was negligible. In multivariate analysis, 2 models were considered: one with log(ER), pS2, CathD and the interaction between pS2 and CathD, and another with log(PgR), pS2, CathD and the interaction between pS2 and CathD. In the first model, log(ER) content did not have a significant prognostic role, whereas in the second model log(PgR) retained a significant prognostic role. Our findings indicate that the quantitative determination of pS2 and CathD, in addition to steroid receptors, on the same cytosolic fraction could be a complementary tool to describe all breast cancer patients rather than just the elderly and that the use of a continuous scale, instead of a simple dichotomous “status”, may improve the biological information supplied by the variables. Int. J. Cancer (Pred. Oncol.) 79:305–311, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
89.
We report on a child with mild mental retardation, hypotelorism, blepharophimosis, face slight asymmetry and partial hypoplasia of corpus callosum, with an interstitial deletion of a chromosome 15. The deletion was molecularly characterized by array-CGH and FISH techniques. This rearrangement has a 7.18 Mb extension and maps to 15q21.2q22.1. To date, there have been only six individuals reported with a deletion of 15q21; in three cases, the rearrangement was characterized by molecular cytogenetic techniques. After a comparison with these three cases, it appeared that the deletion we found is one of the smallest and it overlaps the distal portion of the ones taken into account. Finally, we tried to delineate the genotype–phenotype correlation in patients with a deletion of 15q21.  相似文献   
90.
Objective: The aim of this study was to evaluate the association between umbilical arterial pH and fetal vertebral artery Doppler velocimetry waveforms measured at the beginning of the second stage of labor in physiological term pregnancies.

Methods: This was a prospective cohort study of 250 pregnancies. The resistance index, pulsatility index, and peak systolic velocity were measured. The relationship between the fetal Doppler and the umbilical arterial pH was evaluated. A simple linear regression and a general linear model were used to explore possible correlations of Doppler parameters with fetal and neonatal outcome adjusted for confundents.

Results: Umbilical arterial pH values were directly associated with vertebral artery pulsatility index. Fetuses with lower pulsatility index values were at increased risk of a subsequent diagnosis of pathological fetal heart rate tracing patterns (presence of decelerations or reduced variability according to FIGO criteria during the second stage of labor). We estimated a decrease in pulsatility index of 10% in those fetuses destined to show a pathological fetal heart rate tracing.

Conclusion: Vertebral artery Doppler waveforms correlates with umbilical pH in normal pregnancies and is also a function of fetal heart rate patterns. If this proportional association would be demonstrated also for abnormal pH values, vertebral artery pulsatility index might be useful to evaluate fetal wellbeing in those cases of suspected hypoxia/academia.  相似文献   

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