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991.
The aim of this study was to investigate whether thiamine pyrophosphate (TPP) has biochemical and histological preventive effects on oxidative liver damage induced by paracetamol (APAP). Rats were divided into the following groups: healthy control (HG), APAP (AG, 1500 mg/kg, orally), thiamine pyrophosphate (TPPG, 100 mg/kg, intraperitoneally), APAP+NAC (ANAC, 100 mg/kg, intraperitoneally), APAP+TPP (ATPG) and APAP+NAC+TPP (ANTG). Oxidant, antioxidant parameters, liver function tests and histological assessment were performed between groups. Malondialdehyde levels in the AG, HG, TPPG, ANAC, ATPG and ANTG groups were 0.470 ± 0.210, 0.213 ± 0.004, 0.194 ± 0.001, 0.197 ± 0.06, 0.199 ± 0.008 and 0.173 ± 0.010 μmol/g protein, respectively. Total glutathione levels were 7.787 ± 0.395, 14.925 ± 0.932, 13.200 ± 0.984, 13.162 ± 0.486, 13.287 ± 0.787 and 13.500 ± 0.891 μm /g protein, respectively. In the AG group, marked liver damage occurred with the elevation of liver function tests and oxidative stress markers, such as malondialdehyde, myeloperoxidase and nitric oxide (p < 0.05). Biochemical results were congruent with the histological changes of oxidative damage. Compared to the AG group (p < 0.05), TPP significantly reduced oxidant parameter levels in the ATPG group and simultaneously increased the antioxidant parameter levels of catalase and glutathione. The histological changes were improved to almost normal hepatic structure. Moreover, TPP had nearly the same hepatoprotective effect as NAC, and there was statistically no additional benefit with NAC co‐treatment. There was no statistically significant difference (p > 0.05) among the ANAC, ANTG and ATPG groups in terms of oxidant/antioxidant levels. TPP proved to be as efficacious as standard therapy and may be beneficial in APAP‐induced hepatotoxicity.  相似文献   
992.
To investigate the efficacy of single-dose intravitreal dexamethasone implantation in the treatment of persistent diabetic macular edema (DME) unresponsive to 3 consecutive ranibizumab injections over a period of 6 months. Forty-one patients with a previous history of treatment for DME including at least three consecutive intravitreal ranibizumab injections were enrolled in this retrospective study. Main outcome measures were change in best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure from baseline to 6th month. At the baseline, the mean CMT was 572.4 ± 123.1 μm which improved to 264.2 ± 114.4, 317.7 ± 141.7, 410.6 ± 169.1, and 382.8 ± 181.5 μm at the 1st, 3rd, 5th, and 6th month, respectively (p < 0.05). The preoperative mean BCVA was 0.85 ± 0.54 logMAR units which improved to 0.76 ± 0.5 (p = 0.08), 0.69 ± 0.4 (p = 0.02), 0.74 ± 0.4 (p = 0.284), and 0.72 ± 0.3 (p = 0.489) logMAR units at the 1st, 3rd, 5th, and 6th months, respectively. Additional injections were required for 13 (31 %) eyes at 3rd month and 14 (34 %) eyes at 5th month due to recurrence of macular edema. Intravitreal dexamethasone implantation caused a significant improvement of BCVA and reduction of CMT in the patients with persistent DME that were unresponsive to 3 consecutive ranibizumab injections. However, retreatment before 6 months in the majority of the patients was needed despite the beneficial effects after the index procedure.  相似文献   
993.

Objectives

Paraquat (PQ) is a widely used herbicide. Exposure to PQ at toxic doses can result in fatal acute lung injury. Inhibition of the poly-(ADP-ribose) polymerase (PARP) enzyme alleviates inflammation and necrosis in various pathologies. Here we aimed to evaluate the effects of PARP inhibition on PQ-induced lung damage in a rat experimental model.

Methods

Female Sprague-Dawley rats (n = 24) were allocated into three groups: sham, PQ and PQ + 3-aminobenzamide (3-AB) that is a PARP inhibitor, groups. Experimental lung injury was induced by administration of 15 mg/kg PQ intraperitoneally in PQ and PQ + 3-AB groups. 3-AB (10 mg/kg twice per day) was administered to the PQ + 3-AB group for four consecutive days. The animals were killed on the fifth day following PQ administration. Lung tissue and blood samples were collected and stored until analysis.

Results

Serum lactate dehydrogenase (LDH) and neopterin levels, tissue oxidative stress parameters, transforming growth factor-beta1 (TGF-β) levels and histological injury scores in the PQ + 3-AB group were significantly lower than in the PQ group (P < 0.05, PQ vs. PQ + 3-AB). Total antioxidant capacity in the PQ + 3-AB group was significantly higher than in the PQ group (P < 0.05, PQ + 3-AB vs. PQ).

Conclusion

Our results suggested that the use of PARP inhibitors following PQ toxicity might be useful for minimizing lung injury due to paraquat toxicity.
  相似文献   
994.
The purpose of this study was to determine whether different types of antimicrobial agents with hydrophilic primer applied to etched enamel surfaces will affect the shear bond strength (SBS) and the bracket/adhesive failure modes of metallic orthodontic brackets. Eighty noncarious human premolars were divided into four groups of 20 each. A composite resin (Transbond XT) was used to bond stainless steel brackets. Teeth in the first group were used as a control and bonded with standard procedures. For the other three groups, mixtures containing a hydrophilic primer (Transbond MIP) and one of three anti-microbial agents were prepared (Cervitec: in 1:2 ratio; chlorhexidine mouthwash and EC40 varnish in 1:1 ratio). These mixtures were applied to the etched enamel surfaces and thoroughly light cured for 20 seconds, and the brackets were bonded and light cured for 40 seconds. The SBS values of these brackets (Mpa) were recorded using a universal testing machine. Adhesive Remnant Index scores were determined after failure of the brackets. Data were analyzed using analysis of variance (ANOVA), Tukey honestly significant difference, and chi-square tests. Results of ANOVA revealed statistically significant differences in bond strengths among the various groups tested (P < .05). The bond strength values in these four groups compared favorably with those from other studies and the minimal bond strength values that are clinically acceptable. However, results of this study demonstrated that groups 1 (control) and 2 (Cervitec varnish) had higher SBS values than the other applications. Application of different antimicrobial agents may result in differences in the site of failure.  相似文献   
995.
Abstract –  A retrospective study was carried out on the dental trauma records of 93 patients (55 boys, 38 girls) with 129 crown-fractured teeth. The patients' average age was 9.57 years (SD 1.57), ranging between 7 and 15 years. Uncomplicated crown facture (comprising enamel–dentin) was the most observed type of injury ( n  = 107, 83%). Only 15 patients (16.13%) sought treatment in less than 24 h following the injury. Of 41 injured teeth (31.79%) the apices were open at the time of presentation at the clinic. The initial treatment of these injured teeth were interim restoration with acid-etch and composite (69%), Cvek amputation (2.33%), fragment reattachment (1.55%), apexification (APX, 10.07%), and root-canal treatment (RCT, 17.05%). Out of 94 teeth, which were diagnosed as vital on admittance, 23 (24.46%) later developed pulp necrosis and required APX or RCT depending on their apical status. In 66 teeth (51.16%) definitive treatment was provided with only esthetic restoration (ER), while in 15.50% and 26.68% of injured teeth ER was carried out following APX and RCT, and RCT, respectively. Definitive treatment was provided in 3–6 months for 29.45% of the injured teeth, while 27.13% and 20.16% of teeth received definitive treatment within 1–3 months and 6 months to 1 year, respectively. Type of crown-fracture, elapsed time following injury, and vitality of the tooth on admittance and pulp necrosis observed were significantly related to the total time spent for definitive treatment ( P  < 0.05).  相似文献   
996.
There are plenty of flaps for the reconstruction of defects of the head and neck region. In the literature, local muscle and myocutaneous flaps such as sternocleidomastoid, pectoral, and deltopectoral flaps are proposed for obliteration of pharyngocutaneous fistulas. Restoration of facial nerve palsies in which nerve repair and nerve grafting are not feasible is accomplished by means of regional muscle transpositions. The vascular anatomy of the digastric muscle to be used in such instances is investigated after latex application to 18 neck regions of nine cadavers. The dissection continued anteriorly from the origin of the facial artery to the end of the submental artery, preserving all the branches piercing and nourishing the muscle. The submental artery courses over the posterior surface of the anterior belly of the digastric muscle, giving off the major pedicle of the muscle 1 cm after exiting behind the submandibular gland. The submental artery gives off another branch, the first minor pedicle of the muscle distal to the major pedicle at a distance of two thirds of the muscle length in a standard fashion in all the cadavers. The artery ends in the distal portion of the muscle, the second minor pedicle of the muscle. The artery gives off periosteal branches to the mandible after coursing through the insertion muscle. The anterior belly of the digastric muscle could be classified as a type II muscle, with a major pedicle and two minor pedicles, according to the system of Mathes and Nahai. The anterior digastric muscle can be a good alternative in obliteration of pharyngocutaneous fistulas, and defects of the mandible, including the body and angle of the mandible, can be amended with the split mandibular myo-osseous digastric flap.  相似文献   
997.
The aims of this study were to evaluate the prevalence and risk factors of dental caries, and to determine whether there is any relationship between a fluoride-releasing adhesive material and the development of dental caries in the first year in children with insulin-dependent diabetics (IDDM). The average age of the subjects was 4-15 years, and they had been suffering from IDDM for at least 2 years. The DMF/df(t) indices of 70 patients were calculated and total HbA1 (%) (glucose levels of blood) values were recorded from the medical records after clinical examination. The mean DMF/df(t) values of poorly controlled subjects (HbA1 values over 13%) were significantly higher than those of moderately (HbA1, 10.0-12.9%) and well-controlled (HbA1 values, <10%) subjects. The levels of salivary mutans streptococci (MS) and lactobacilli (LB) and the pH of paraffin-stimulated whole saliva were measured in diabetic patients. Salivary MS and LB scores of the poorly controlled subjects were significantly higher (2.5+/-0.7 and 2.1+/-1.0) than those of the moderately (1.6+/-0.9 and 1.1+/-0.8) and well-controlled (1.2+/-1.0 and 0.8+/-0.8) subjects. The mean pH values among all subjects were not statistically significant. All dental caries were restored with a fluoride-releasing adhesive material. At the end of the first year, no new caries or lost restorations were observed in these patients. Moreover, the rate of MS in the poorly and moderately controlled subjects was considerably reduced. However, no significant statistical reduction of MS was determined in the well-controlled subjects. The level of lactobacilli in the poorly controlled, moderately controlled, and well-controlled subjects was reduced.  相似文献   
998.
The term “ES” has been widely used for describing a clinical condition consisting of skin rash, fever, and weight gain that occur during neutrophil recovery period following HSCT. In this study, the incidence, clinical features, risk factors, and outcomes of ES were evaluated in 169 children following allogeneic HSCT from full‐matched related donor according to the Spitzer criteria. Seventeen patients (10.1%) presented with clinical conditions suggesting ES. In both univariate and multivariate analysis underlying malignant disease and early release of monocytes to the PB, and in univariate analysis using only CsA for GVHD prophylaxis were found to be the significant risk factors for the development of ES. Patients with ES experienced significantly higher incidence of acute and chronic GVHD and propensity toward a higher rate of TRM. OS did not differ between the patient groups. Thirteen of 17 patients received steroid therapy, and all but one patient responded to therapy. Monitoring for early detection of ES and early intervention with steroid therapy is the key for recovery. The most crucial approach for this purpose mainly is to find out and use the most useful and feasible diagnostic criteria for routine medical practice.  相似文献   
999.
This prospective, observational, single-center study aimed to determine the perioperative predictors of early extubation (<24 h after cardiac surgery) in a cohort of children undergoing cardiac surgery. Children aged between 1 month and 18 years who were consecutively admitted to pediatric intensive care unit after cardiac surgery for congenital heart disease between January 2012 and June 2014. Ninety-nine patients were qualified for inclusion during the study period. The median duration of mechanical ventilation was 20 h (range 1–480), and 64 patients were extubated within 24 h. Four of them failed the initial attempt at extubation, and the success rate of early extubation was 60.6 %. Older patient age (p = .009), greater body weight (p = .009), absence of preoperative pulmonary hypertension (p = .044), lower RACHS-1 category (OR, 3.8; 95 % CI 1.35–10.7; p < .05), shorter cardiopulmonary bypass (p = .008) and cross-clamp (p = .022) times, lower PRISM III-24 (p < .05) and PELOD (p < .05) scores, lower inotropic score (p < .05) and vasoactive-inotropic score (p < .05), and lower number of organ failures (OR, 2.26; 95 % CI 1.30–3.92; p < .05) were associated with early extubation. Our study establishes that early extubation can be accomplished within the first 24 h after surgery in low- to medium-risk pediatric cardiac surgery patients, especially in older ones undergoing low-complexity procedures. A large prospective multiple institution trial is necessary to identify the predictors and benefits of early extubation and to facilitate defined guidelines for early extubation.  相似文献   
1000.
To investigate the potential protective effects of losartan on varicocele‐induced germ cell apoptosis, 24 adult male Sprague Dawley rats were divided into three groups: a sham operation was performed in SHAM group, and experimental left varicocele was created in VAR and VAR + LOS groups. Additionally, in VAR + LOS group, losartan was administered for 30 days starting on the day of surgery. At the end of 30 days, all animals were sacrificed and left orchiectomy was performed. Testicular injury and spermatogenesis were evaluated according to Johnsen scoring system. To assess the nitrosative stress, immunohistochemical staining for endothelial nitric oxide synthase was used and evaluated by H‐score and apoptotic index (AI) of germ cells was analysed by TUNEL method. A significant decrease in the mean Johnsen score (JS) was observed in VAR group compared with SHAM (p < .001). The mean H‐score and AI were significantly higher in VAR group compared with SHAM (p < .001). After losartan administration, mean JS was significantly increased (p < .001) and mean H‐score and AI were significantly decreased compared with VAR group (p < .001 and .01, respectively). Findings of this suggest that losartan acts as a potent protective agent against varicocele‐induced germ cell apoptosis.  相似文献   
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