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81.
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate vascular microcirculation changes of the optic nerve head (ONH) in the patients with asymmetric pseudoexfoliative...  相似文献   
82.
Skin reactions against injected or implanted foreign materials are not rare. Siderosis is a disease characterized by the accumulation of iron in various tissues. Brownish-gray discoloration of the skin can be seen as a side-effect on the injection area after the parenteral iron treatment. Here, we present cutaneous siderosis case developed after multiple intramuscular iron injection on the gluteal region for iron-deficiency anemia. Development of cutaneous siderosis after intramuscular iron injection rarely has been reported in the literature before.  相似文献   
83.

Purpose

PDE5 inhibitors are widely used for the treatment of erectile dysfunction. However, these drugs have recently become popular among men without erectile dysfunction as a means of enhancing sexual performance and improving sexual desire. The aim of this study was to investigate the histopathological and ultrastructural effects of PDE5 inhibitors on the corpus cavernosum in young, healthy male rats.

Methods

Twenty-four 4-month-old male rats were divided into four groups: group 1 was the control group, group 2 rats received sildenafil citrate, group 3 rats received vardenafil hydrochloride, and group 4 rats received tadalafil. All drugs were administered for 4 weeks. Penile tissue was collected for electron microscopy and tissue collagen measurements. Electron microscopic analysis indicated that the number of active fibroblasts and macrophages and the synthesis of new collagen fibers increased in treated rats.

Results

Cavernous tissue collagen levels were significantly higher in the sildenafil-, vardenafil-, and tadalafil-treated groups than in controls (46.16 ± 4.9, 42.06 ± 2.4, 41.07 ± 2.4, and 29.20 ± 3.3, respectively) (p < 0.001).

Conclusions

Young men who use these drugs to enhance performance in the absence of erectile dysfunction may experience irreversible damage to the cavernosal tissue. However, more studies are needed to evaluate the molecular mechanisms by which PDE5 inhibitors affect the corpus cavernosum.  相似文献   
84.
Objectives. Vitamin D regulates calcium and bone homeostasis, and parathyroid hormone (PTH) secretion. Cross-sectional associations between lower vitamin D levels and cardiovascular diseases have been reported, but the relationship between vitamin D levels and collateral arteries in stable coronary artery disease (CAD) has not been reported before. Design. Two hundred and fourteen patients with above 95% stenosis in at least one epicardial coronary artery were consecutively recruited after coronary angiography (CAG) during the winter season. The coronary collateral circulation (CCC) was graded using Rentrop classification. Poor CCC group included patients with Rentrop Grade 0–1 CCC and control group included patients with Rentrop Grade 2–3 CCC. Vitamin D and PTH levels were measured on the day of CAG. Results. In the poor CCC group, vitamin D levels were lower (34 ± 25 pmol/L vs. 49 ± 33 pmol/L; p = 0.01) and the prevalence of vitamin D deficiency (< 37 pmol/L) was higher (67% vs. 43%; p = 0.01) compared to the controls. PTH levels, calcium, and phosphate levels were not significantly different between the groups. Female gender, lower HDL cholesterol, and lower vitamin D levels were independently correlated with poor CCC in the study population. Conclusion. Lower vitamin D levels may be associated with poor collateral development in patients with stable CAD.  相似文献   
85.
Primary drug resistance is a major problem in multiple myeloma, an incurable disease of the bone marrow. Cell adhesion-mediated drug resistance (CAM-DR) causes strong primary resistance. By coculturing multiple myeloma cells with bone marrow stromal cells (BMSCs), we observed a CAM-DR of about 50% to melphalan, treosulfan, doxorubicin, dexamethasone, and bortezomib, which was not reversed by secreted soluble factors. Targeting the adhesion molecules lymphocyte function-associated antigen 1 (LFA-1) and very late antigen 4 (VLA-4) by monoclonal antibodies or by the LFA-1 inhibitor LFA703 reduced CAM-DR significantly. Only statins such as simvastatin and lovastatin, however, were able to completely restore chemosensitivity. All these effects were not mediated by deadhesion or reduced secretion of interleukin 6. Targeting geranylgeranyl transferase (GGTase) and Rho kinase by specific inhibitors (GGTI-298 and Y-27632), but not inhibition of farnesyl transferase (FTase) by FTI-277, showed similar reduction of CAM-DR. Addition of geranylgeranyl pyrophosphate (GG-PP), but not of farnesyl pyrophosphate (F-PP), was able to inhibit simvastatin-induced CAM-DR reversal. Our data suggest that the 3-hydroxy-3-methylglutaryl-coenzyme-A (HMG-CoA)/GG-PP/Rho/Rho-kinase pathway mediates CAM-DR and that targeting this pathway may improve the efficacy of antimyeloma therapies by reduction of CAM-DR.  相似文献   
86.

Aim

Over the past 2 decades, transcatheter occlusion of patent ductus arteriosus (PDA) with coils and the duct occluders evolved to be the procedure of choice. A new device, the Occlutech PDA® occluder (ODO) device has been designed. Herein, we aimed to evaluate the characteristics and short‐term results of patients who underwent transcatheter closure of PDA using the ODO.

Methods

We reviewed the clinical records of 60 patients from different centers in Turkey between December 2013 and January 2016. The medical records were reviewed for demographic characteristics and echocardiographic findings. Device size was selected on the narrowest diameter of PDA.

Results

The median patient age was 2.5 years (6 months–35 years), and median PDA diameter was 2.5 mm (1.2–11 mm). Fifty‐eight of 60 patients (96.6%) had successful ODO implantation. The occlusion rates were 37/58 (63.7%) at the end of the procedure, 51/58 (87.9%) at 24–48 hours post‐procedure, and 57/58 (98.2%) on echocardiography at a median follow‐up of 7.6 months.

Conclusion

Our results indicate that transcatheter closure of PDA using the ODO is effective. Larger studies and longer follow‐up are required to assess whether its shape and longer length make it superior to other duct occluders in large, tubular, or window‐type ducts. (J Interven Cardiol 2016;29:325–331)
  相似文献   
87.
There have been considerable advances in uncovering the complex genetic mechanisms that underlie nervous system disease pathogenesis, particularly with the advent of exome and whole genome sequencing techniques. The emerging field of epigenetics is also providing further insights into these mechanisms. Here, we discuss our understanding of the interplay that exists between genetic and epigenetic mechanisms in these disorders, highlighting the nascent field of epigenetic epidemiology—which focuses on analyzing relationships between the epigenome and environmental exposures, development and aging, other health-related phenotypes, and disease states—and next-generation research tools (i.e., those leveraging synthetic and chemical biology and optogenetics) for examining precisely how epigenetic modifications at specific genomic sites affect disease processes.  相似文献   
88.
Objectives

There are no studies that have assessed the oral soft tissue response to full-mouth ultrasonic scaling (FMUS) among cigarette-smokers (CS) (group 1), individuals vaping electronic-cigarettes (E-cigs) (group 2), and never-smokers (NS) (group 3). The aim was to assess the impact of cigarette smoking and vaping on periodontal tissues following FMUS.

Materials and methods

In a clinical prospective study, 89 male individuals were divided into three groups: CS (group 1), E-cig users (group 2), and NS (group 3). A questionnaire was used to gather demographic data and information regarding duration and daily frequency of CS and vaping. Full-mouth plaque index (PI), bleeding on probing (BOP), clinical attachment loss (AL), and probing depth (PD) were measured at baseline and 3 and 6 months after FMUS (without root surface debridement). Numbers of missing teeth (MT) were also recorded.

Results

In groups 1, 2, and 3, 30, 28, and 31 individuals, respectively were included. In group 1, there was no statistically significant difference in mean PI and PD and numbers of sites with PD ≥ 4 mm at 6 months’ follow-up compared with baseline and 3 months’ follow-up. In groups 2 and 3, there was no significant difference in PI, BOP, and PD at 3 months’ (P > 0.05) and 6-months’ (P > 0.05) follow-up. There were no pockets with PD ≥ 4 mm at 3 and 6 months’ follow-up in groups 2 and 3. There was no difference in the numbers of MT and none of the individuals exhibited clinical AL in all groups.

Conclusion

Following FMUS, gingival inflammation is worse in CS compared with individuals vaping E-cigs and NS.

Clinical relevance

Periodontal inflammatory parameters are worse in cigarette-smokers than individuals vaping electronic cigarettes and never-smokers following FMUS. However, these findings should be interpreted with extreme caution as a number of factors may have influenced the present results.

  相似文献   
89.
In this paper, we study double cascade dressed optical metal oxide semiconductor field-effect transistor (MOSFET) by exploiting enhancement and suppression for mixed-phase (hexagonal + tetragonal) of Eu3+:YPO4 and different phases (hexagonal + tetragonal and pure tetragonal) of Pr3+:YPO4 crystals. We report variation of fine structure energy levels in different doped ions (Eu3+ and Pr3+) in the host YPO crystal. We compared multi-level energy transition from a single dressing laser with single level energy transition from double cascade dressing lasers. Gate delay facilitates multi-energy level dressed transition and is modeled through a Hamiltonian. Based on the results of double cascade dressing, we have realized MOSFET for logic gates (inverter and logic not and gate) with a switching contrast of about 92% using a mixed phase of Pr3+:YPO4.

By changing different parameters of single and double lasers, we observed the dressed energy level transition from single to multi-level with a single laser. Each sample responded based on their ions'' structure and phase symmetry in the host YPO crystal.  相似文献   
90.
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