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The ability of iron to cycle reversibly between its ferrous and ferric oxidation states is essential for the biological functions of iron but may contribute to vascular injury through the generation of powerful oxidant species. We examined the association between chemical forms of iron that can participate in redox cycling, often referred to as "catalytic" or "labile" iron, and cardiovascular disease (CVD). In our cross-sectional study of 496 participants, 85 had CVD. Serum catalytic iron was measured using the bleomycin-detectable iron assay that detects biologically active iron. The odds of existing CVD for subjects in the upper third of catalytic iron were 10 times that of subjects with lower catalytic iron in unadjusted analyses. The association was decreased by 1/2 by age adjustment, but little additional attenuation occurred after adjusting for age, Framingham Risk Score, estimated glomerular filtration rate, hypertension status, high-density lipoprotein cholesterol, and systolic blood pressure, with the association remaining strong and significant (odds ratio 3.8, 95% confidence interval 1.4 to 10.1). In conclusion, we provide preliminary evidence for a strong detrimental association between high serum catalytic iron and CVD even after adjusting for several co-morbid conditions; however, broader prospective studies are needed to confirm these findings, which would support therapeutic trials to assess the beneficial effects of iron chelators on CVD.  相似文献   
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Purpose

This study is an attempt to evaluate the use of autologous platelet rich plasma (PRP) to promote wound healing and osseous regeneration in human third molar extraction sockets.

Materials and method

PRP was prepared after two centrifugation and the gelling agent used was freshly prepared 10% calcium chloride.PRP gel was placed in one of the extracted sockets of bilateral impacted mandibular third molars. IOPA Xrays were used to evaluate the wound dehiscence, probing depth, bone density & alveolar bone level after 1st, 2nd and 7th day and 3rd & 6th month respectively.

Results

On evaluation, it was found that PRP grafted sockets showed dehiscence in 8% cases. The decrease in alveolar bone level was highly significant in PRP grafted sockets in 3rd and 6th month post operatively. There was significant difference between pre-operative density of adjacent bone and bone formed in extraction sockets at 3rd and 6th month in PRP grafted sockets. There was significant reduction in probing depth from initial period to 3 and 6 months in both the groups, but PRP grafted sockets showed greater decrease in probing depth.

Conclusion

PRP is an inexpensive and widely available modality to minimize postoperative complication and enhance both hard and soft tissue healing potentials. This autologous product eliminates concern about immunogenic reaction and disease transmission. Its beneficial outcomes in dental clinic, including decrease in bleeding and rapid wound healing hold promise for further procedures.PRP is thus a new application in tissue engineering and developing area for clinician and researchers.  相似文献   
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Purpose

To evaluate the incidence and recovery of persistent sensory disturbances of the infraorbital (IO) nerve after isolated zygomatic complex fractures with various treatment methods.

Methods and Results

The study was inclusive of isolated unilateral zygomatic complex fractures and fractures of IO rim .Tests performed were Pin prick and Electrical detection threshold test. The evaluation was done preoperatively, after 1 month and after 6 months of surgery. The results suggested that neurosensory disturbance was present in all the patients with zygomatic complex fractures. At 1 month post-operatively some sensory deficit was present in all the patients on the affected side. After 6 months all the patients showed near to normal improvement comparable to normal side.

Conclusion

Study shows that earlier the surgical intervention, more the recovery of the nerve injury is appreciable during the 1 and 6  months follow up period.  相似文献   
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Purpose:The aim of this study is to evaluate the accuracy of three newer generation formulae (Barrett Universal II, EVO, Hill-RBF 2.0) for calculation of power of two standard IOLs—the Acrysof IQ and Tecnis ZCB00 across all axial lengths.Methods:In this retrospective series, 206 eyes of 206 patients, operated for cataract surgery with above two IOLs over the last 6 months, were included in the study. Preoperative biometry measurements were obtained from LenstarLS900. By using recommended lens constants, the mean error for each formula was calculated and compared. Then, the optimized IOL constants were calculated to reduce the mean error to zero. Mean and median absolute errors were calculated for all eyes and separately for short (AL<22.5 mm), medium (22.5–24.5 mm), and long eyes (>24.5 mm). Absolute errors and percentages of eyes within prediction errors of ±0.25 D, ±0.50 D, ±0.75 D, and ±1.00 D were compared.Results:Prediction error with using recommended lens constants was significantly lower in the Barrett Universal II formula as compared to the other two formulae. However, after optimizing lens constants, there were no significant differences in the absolute errors between the three formulae. The formulae ranked by mean absolute error were as follows: Barrett Universal II (0.304 D), EVO (0.317 D), and Hill-RBF (0.322) D. There were no significant differences between absolute errors in the three formulae in each of the short-, medium-, and long-eye subgroups.Conclusion:With proper lens constant optimization, the Barrett Universal II, EVO, and Hill-RBF 2.0 formulae were equally accurate in predicting IOL power across the entire range of axial lengths.  相似文献   
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Commonly, a groin defect is reconstructed with flaps from ipsilateral thigh or lower abdomen. Here we present a case report of use of a pedicled flap from the posterior scrotum based on posterior scrotal artery to cover a groin defect exposing femoral vessels. Posterior scrotal artery, to best of our knowledge, has not been described in the literature to cover a groin defect.  相似文献   
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Parathyroid hormone (PTH) has been a major contributor to the anabolic therapy for osteoporosis, but its delivery to bone without losing activity and avoiding adverse local effects remain a challenge. Being the natural component of bone, use of hydroxyapatite for this purpose brings a major breakthrough in synergistic anabolism. This study focuses on synthesis, characterization and evaluation of in vitro and in vivo efficacy of PTH (1-34) adsorbed hydroxyapatite nanocarrier for synergistic enhancement in the anabolic activity of PTH for bone regeneration. The negative zeta potential of this nanocarrier facilitated its affinity to the Ca2+ rich bone tissue and solubilization at low pH enhanced specific delivery of PTH to the resorption pits in osteoporotic bone. In this process, PTH retained its anabolic effect and at the same time an increase in bone mineral content indicated enhancement of the net formative effect of the PTH anabolic therapy.  相似文献   
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Various polyoxylglycerides have been researched extensively in the development of solid dispersions (SDs) for bioavailability enhancement of poorly water-soluble drugs. However, because of their low melting points (40°C-60°C), SDs produced are usually soft and semisolid. The objective of present study was to prepare SDs of a Biopharmaceutical Classification System class II drug, carvedilol, in mixtures of stearoyl polyoxylglycerides (Acconon® C-50; m.p. ~50°C) with polymers by hot melt extrusion to obtain free-flowing powder upon grinding. Miscibility of carvedilol with Kollidon® VA64, hydroxypropyl methylcellulose acetate succinate, and Klucel? EXF was first evaluated by film casting, and Kollidon® VA64 was selected for further study. SDs containing 5%-20% carvedilol, 0%-20% Acconon® C-50, and the remaining Kollidon® VA64 were prepared for hot melt extrusion. SDs were characterized by differential scanning calorimetry and powder X-ray diffraction analysis, and dissolution tests were conducted in 250 mL of pH 6.8 phosphate buffer by filling powders in capsules. Carvedilol was miscible with all polymers tested up to 50% and remained amorphous in SDs. The drug release from formulations containing 20% carvedilol and 0, 5%, 10%, and 20% Acconon® C-50 were 30%, 30%, 70%, and 90%, respectively, in 60 min. SDs containing carvedilol and Acconon® C-50, up to 20% each, as well as Kollidon® VA64, were physically stable after 3 months of storage at 25°C/60% relative humidity.  相似文献   
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