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51.
Glaucoma is one of the leading causes of blindness. Therapies available suffer from several drawbacks including low bioavailability, repeated administration and poor patient compliance with adverse effects thereafter. In this study, bovine serum albumin nanoparticles (BSA-NPs) coated with chitosan(CS) were developed for the topical delivery of tetrandrine (TET) for glaucoma management. Optimized nanoparticles were prepared by desolvation. pH, BSA, CS and cross-linking agent concentrations effects on BSA-NPs colloidal properties were investigated. CS-BSA-NPs with particle size 237.9 nm and zeta potential 24 mV was selected for further evaluation. EE% exceeded 95% with sustained release profile. In vitro mucoadhesion was evaluated based on changes in viscosity and zeta potential upon incubation with mucin. Ex vivo transcorneal permeation was significantly enhanced for CS coated formulation. In vitro cell culture studies on corneal stromal fibroblasts revealed NPs biocompatibility with enhanced cellular uptake and improved antioxidant and anti-proliferative properties for the CS-coated formulation. Moreover, BSA-NPs were nonirritant as shown by HET-CAM test. Also, bioavailability in rabbit aqueous humor showed 2-fold increase for CS-TET-BSA-NPs compared to TET with a sustained reduction in intraocular pressure in a rabbit glaucoma model. Overall, results suggest CS-BSA-NPs as a promising platform for topical ocular TET delivery in the management of glaucoma.  相似文献   
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Purpose

To differentiate pediatric solid malignant from the benign parotid tumors with diffusion-weighted MR imaging (DWI).

Materials and methods

A retrospective study comprising 38 children with parotid tumors (21 boys and 17 girls aged from 2 months to 17 years) was conducted using (DWI) of the parotid gland. Apparent diffusion coefficient (ADC) maps were generated. The ADC value of the parotid tumors was calculated.

Results

The mean ADC value of malignant parotid tumors (1.08?±?0.1, 1.04?±?0.1?×?10?3mm2/s) was significantly lower [P?=?0.001] than that of benign lesions (1.69?±?0.2, 1.72?±?0.3?×?10?3mm2/s). A threshold of ADC of 1.40, 1.33?×?10?3mm2/s was used for differentiating malignant parotid tumors from benign lesions and led to the best results of the area under the curve of 0.940, 0.929, accuracy of 86, 89%, sensitivity of 94, 94%, specificity of 80, 85%, negative predictive value of 94.1, 94.4%, and positive predictive value of 81, 85%. There was insignificant difference in ADC values of malignant lesions (P?=?0.23, 0.30) as well as within benign lesions (P?=?0.25, 0.08).

Conclusion

DWI is an innovative anticipating imaging technique that can be used in the differentiation of pediatric solid malignant parotid tumors from benign lesions.

  相似文献   
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This study dealt with the effect of citrate phosphate dextrose adenine (CPDA) whole blood stored at 4 degrees C for 5 weeks and fresh frozen plasma at -30 degrees C for 12 months on coagulation, fibrinolytic and kallikrein system activation. Stored whole blood showed a significant decrease in ATIII activity by the second week with a significant decrease in thrombin-antithrombin complex by the fourth week. alpha 2-antiplasmin and plasminogen decreased significantly by the first and second week, respectively, accompanied by a significant increase in D-dimer level by the fourth week. A significant decrease in C1-inhibitor activity occurred by the first week associated with a significant increase in kallikrein activity by the third week. However, all measured parameters were minimally affected in fresh frozen plasma. Therefore, fresh frozen plasma supplemented with packed RBCs are preferred to whole blood stored over 3 weeks especially in patients with proteolytic enzyme system activation.  相似文献   
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Background Odontogenic tumors (OTs) are considered important among oral lesions because of their clinicopathological heterogeneity and variable biological behavior. The purpose of this retrospective cross-sectional study was to evaluate the frequency and distribution of different types of odontogenic tumors based on the current 2017 WHO Classification of Head and Neck Tumors over a period of 5 years. This was achieved by reviewing the records of Cairo''s educational hospitals and institutions and comparing the results with findings in the literature.Material and Methods The records of patients diagnosed with odontogenic tumors were obtained from six educational hospitals and a single institute in Cairo which included: Oral and Maxillofacial Pathology Department, Faculty of Dentistry, Cairo University; General Pathology Department, Faculty of Medicine, Cairo University; Oral Pathology Department, Faculty of Dentistry, Ain Shams University; Eldemerdash Hospital, Ain Shams University; El-Sayed Galal Hospital, Al-Azhar University; Ahmed Maher Teaching Hospital and National Cancer Institute. These records were reviewed over a 5-year (2014-2018) period and the odontogenic tumors were investigated for frequency, age, gender and site. The data were recorded, then analyzed using SPSS software.Results Intraosseous (central) odontogenic tumors constituted 2.56% of all 8974 registered oral and maxillofacial biopsies. A total of 230 cases of OTs were collected and reviewed. Of these, 97.8% were benign and 2.17% were malignant. The mandible was the most commonly affected anatomic location. Ameloblastoma, with a predilection for the posterior mandible, was the most frequent odontogenic tumor (55.65%), followed by cemento-ossifying fibroma (14.78%) and odontoma (9.13%). Females were more commonly affected than males. Most of the patients were in the third and fourth decades of life. There were no peripheral odontogenic tumors diagnosed in this period.Conclusions Some similarities and differences between our findings and those of previous studies of various populations were witnessed. OTs may greatly diverge according to the version of the classification used and by the sample size of the study. Retrospective analysis of the relative frequency of OTs in different countries will be helpful in enhancing the understanding of OTs, which is important for both oral maxillofacial surgeons and pathologists. Key words:Odontogenic tumors, epidemiology, world health organization classification, oral pathology.  相似文献   
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Objective: To investigate the effect of Cannabis sativa extract on the development of neuroand hepato-toxicity caused by malathion injection in rats. Methods: The extract of Cannabis sativa was obtained from the plant resin by chloroform treatment. Δ~9-Tetrahydrocannabinol content of the extract(20%) was quantified using gas chromatography–mass spectrometry. The doses of cannabis extract were expressed as Δ~9-tetrahydrocannabinol content of 10 or 20 mg/kg. Malathion(150 mg/kg) was intraperitoneally administered followed after 30 min by the cannabis extract(10 or 20 mg/kg, subcutaneously). Rats were euthanized 4 h later. Malondialdehyde(MDA), reduced glutathione(GSH), nitric oxide and paraoxonase-1(PON-1) activity were determined in brain and liver. Brain 5-lipoxygenase and butyrylcholinesterase(BChE) activity were measured as well. Histopathological examination of brain and liver tissue was also performed. Results: Compared to controls, malathion resulted in increased oxidative stress in brain and liver. MDA and nitric oxide concentrations were significantly increased(P0.05) and GSH significantly decreased with respect to control levels(P0.05). Malathion also significantly inhibited PON-1 and BChE activities but had no effect on brain 5-lipoxygenase. Brain MDA concentrations were not altered by cannabis treatment. Cannabis at 20 mg/kg, however, caused significant increase in nitric oxide and restored the GSH and PON-1 activity. Brain BChE activity significantly decreased by 26.1%(P0.05) after treatment with 10 mg/kg cannabis. Cannabis showed no effect on brain 5-lipoxygenase. On the other hand, rats treated with cannabis exhibited significantly higher levels of liver MDA, nitric oxide and PON-1 activity compared with the malathion control group. Rats treated with only malathion exhibited spongiform changes, neuronal damage in the cerebral cortex and degeneration of some Purkinje cells in the cerebellum. There were also hepatic vacuolar degeneration and dilated and congested portal vein. These histopthological changes induced by malathion in brain and liver were reduced to great extent by cannabis administration at 20 mg/kg. Conclusions: Our data suggest that acute treatment with cannabis alleviates the malathion-induced brain and hepatic injury in rats possibly by maintaining the levels of GSH and PON-1 activity.  相似文献   
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Objectives: We aimed to evaluate the effect of percutaneous atrial septal defect (ASD) closure in children using right heart indices and serum galectin-3 (Gal-3), as potential biomarkers of right heart remodeling. Methods: This case–control prospective study included 40 children with ASD and 25 control subjects. An echocardiographic evaluation was performed before the procedure, as well as 24 h, 1 month, and 6 months after intervention. Serum Gal-3 was measured before, and 1 month after the procedure. Results: Serum Gal-3 concentration, right atrial (RA) dimensions, right ventricular (RV) dimensions, indexed RA area, and right index of myocardial performance (RIMP) were significantly increased in children with ASD compared with control subjects while tricuspid annular plane systolic excursion (TAPSE) was significantly decreased. Six months after closure, RA, and RV dimensions significantly decreased and RV function improved (RIMP decreased and TAPSE increased). Gal-3 oncentration significantly decreased 1 month after ASD closure, but it did not reach normal range compared with control subjects. A positive correlation between Gal-3 and age at closure, RA area, RV dimensions, and RIMP was observed. A positive correlation was observed between the decrease in Gal-3 concentration and the decrease in RA area and RV dimensions 1 month after ASD closure. A significant negative correlation was observed between TAPSE and Gal-3 concentration before and after intervention. Conclusions: Percutaneous ASD closure can improve right-sided indices and decrease serum Gal-3 concentration. Gal-3 can be used as a sensitive biomarker of right heart remodeling, with a decrease in Gal-3 concentration suggesting reversal of maladaptive remodeling.  相似文献   
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