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排序方式: 共有1909条查询结果,搜索用时 377 毫秒
71.
Ahmed M. Kabel Samir A. Salama Amal A. Alghorabi Remon S. Estfanous 《Clinical and experimental pharmacology & physiology》2020,47(7):1169-1181
Cyclosporine is an immunosuppressive agent that is used to prevent organ rejection after organ transplantation. Due to the widespread use of this type of surgery, the effect of cyclosporine on reproduction and fertility should have a specific interest. Our aim was to assess the effect of carvedilol and/or alpha-lipoic acid on cyclosporine-induced testicular toxicity in rats. Sixty male Wistar rats were divided into six equal groups: Control; cyclosporine; cyclosporine + carvedilol; cyclosporine + alpha-lipoic acid; cyclosporine + carboxymethyl cellulose; and cyclosporine + carvedilol +alpha-lipoic acid. Food intake, testis weight, testicular functions, serum testosterone, luteinizing hormone and follicle-stimulating hormone were measured. Also, testicular tissue 3 β-hydroxysteroid dehydrogenase, 17 β- hydroxysteroid dehydrogenase, paroxonase-1, proinflammatory cytokines, transforming growth factor beta-1, nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/Heme oxygenase-1 (HO-1) content and sperm characteristics were determined. Parts of the testes were subjected to histopathological and electron microscopic examination. The carvedilol/alpha-lipoic acid combination restored the food intake, testicular weight and functions, sperm characteristics, hormonal profile and the antioxidant defences compared to the use of each of these drugs alone. Also, this combination significantly ameliorated inflammation (P < .05) and induced significant increase in tissue Nrf2/HO-1 content (P < .05) and significant improvement of the histopathological and electron microscopic picture (P < .05) compared to the use of each of these drugs alone. So, carvedilol/alpha-lipoic acid combination might represent a novel therapeutic strategy to ameliorate testicular damage induced by cyclosporine. 相似文献
72.
Dana Anaïs Muin Michael Wolzt Safoura Sheikh Rezaei Max Tremmel-Scheinost Mohamed Salama Carola Fuchs 《The European journal of contraception & reproductive health care》2016,21(2):141-149
Objectives The aim of the trial was to assess the effect of self-evaluation and sexual diary keeping on female sexual function and depressive symptoms in women diagnosed with sexual dysfunction.Methods A single-arm non-randomised trial included 30 women (53 ± 7 years of age) with female sexual dysfunction (Female Sexual Function Index [FSFI] < 27) and a stable partnership duration of 5–40 years. Female sexual function was assessed by sexual, psychological and gynaecological history taking and validated questionnaires including the FSFI, Female Sexual Distress Scale (FSDS) and Hamilton Depression Scale (HDS), before and after 4 weeks of sexual diary keeping.Results A subjective improvement in communication of sexual problems was reported by 60% of participants; no participants reported any worsening of communication. FSFI and FSDS scores were, respectively, 18.0 ± 7.7 and 22.0 ± 10.0 at baseline and 20.2 ± 7.2 and 20.6 ± 11.5 after 4 weeks. HDS score decreased from 6.0 ± 4.0 at baseline to 4.4 ± 2.7 after 4 weeks (p = 0.042).Conclusions Self-evaluation and sexual diary keeping may improve aspects of sexual life, such as couple communication, without a direct effect on variables measured with validated questionnaires on different domains of sexual function. 相似文献
73.
Hend E. Salama Magdy W. Sabaa 《Journal of biomaterials science. Polymer edition》2016,27(18):1880-1898
Chitosan biguanidine hydrochloride (ChG) and glutaraldehyde cross-linked chitosan biguanidine (CChG) were synthesized and characterized by Fourier transform infrared spectroscopy, 1H NMR and 13C NMR, X-ray diffraction, scanning electron microscopy (SEM) and thermal analyses (TGA and DTA). The results showed that ChG and CChG had a more amorphous structure than that of chitosan, and their thermal stability were slightly lower than that of chitosan. Colloidal silver nanoparticles (AgNPs) were prepared using borohydride reduction method and then investigated as fillers in partially cross-linked chitosan biguanidine. The obtained nanoparticles were uniform and spherical with average size of 9.6 ± 0.5 nm. The prepared CChG/AgNPs composites were characterized for their morphology, thermal properties, cytotoxicity and antimicrobial activity. The SEM images showed that the AgNPs are well imbedded in the CChG matrix. The thermal stability of CChG was improved with incorporation of AgNPs. The CChG and CChG/AgNPs showed less cytotoxicity to breast cancer cells (MCF-7). Compared with chitosan and CChG, the ChG and CChG/AgNPs showed better antimicrobial activity against Streptococcus pneumoniae and Bacillus subtilis as Gram-positive bacteria, Escherichia coli as Gram-negative bacteria and Aspergillus fumigatus, Geotricum candidum and Syncephalastrum recemosum as fungi. 相似文献
74.
Radioiodination and bioevaluation of rolipram as a tracer for brain imaging: In silico study,molecular modeling and gamma scintigraphy
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M.H. Sanad A.B. Farag Dina H. Salama 《Journal of labelled compounds & radiopharmaceuticals》2018,61(6):501-508
Brain imaging is considered one of the most fruitful applications of radioisotope scanning. Rolipram, a selective phospodiesterase‐4 inhibitor, has been labeled using [125I] with chloramine‐T (Ch‐T) as an oxidizing agent. Factors, such as the amount of substrate, pH, the amount of oxidizing agent, temperature, and the reaction time, have been systematically studied to optimize the iodination process. In addition, bio‐distribution studies have indicated that the brain uptake of [125I]iodorolipram is 7.6 ± 0.33 injected dose/g organ at 10 minutes post‐injection, which cleared from the brain with time until it reaches 1.30 ± 0.17% at 1 hour post‐injection. Therefore, iodorolipram could be considered as a potential, new selective radiotracer for brain imaging. 相似文献
75.
Ridge preservation and augmentation using regenerative materials to enhance implant predictability and esthetics 总被引:2,自引:0,他引:2
Keith JD Salama MA 《Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995)》2007,28(11):614-21; quiz 622-4
Dentistry has entered an era in which patients no longer need to accept an edentulous or partially edentulous condition, or one in which their candidacy for tooth structure replacement (ie, implants with subsequent restoration) must be dismissed because of insufficient alveolar bone volume, height, or width. The supporting bone can be preserved at the time of tooth extraction, or augmented at the time of case presentation, using a variety of available regenerative materials. Among them are mineralized human allograft bone and collagen membranes that can be placed in combination with specific growth factor complexes and implant designs. This article reviews the challenges associated with adequately preserving or augmenting the alveolar bone after tooth extraction or loss and before implant placement. The research and benefits to support using allogenic bone graft and membrane materials for such procedures are detailed, and 3 clinical cases are presented to demonstrate the clinically successful incorporation of these materials with the host tissues. 相似文献
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78.
Ahmed Abd El Wahab Saleh Eman Mahmoud Amin Asmaa Adel Elfallah Ahmed Mohamed Hamed 《Andrologia》2020,52(11):e13773
Among various health issues, infertility has been always considered as one of the major health problems. Idiopathic infertility is still a matter of debate since the underlying mechanisms stay obscure. Idiopathic infertility is related to expanded chance of metabolic syndrome components, obesity and increased risk of cardiovascular diseases. This study aimed to assess insulin resistance and serum levels of irisin as one of the adipokines in patients with idiopathic infertility. This study included 50 male patients aged 25–50 years old suffering from idiopathic infertility, together with 50 healthy individuals of matched age as controls. Patients showed significantly increased homeostasis model assessment for insulin resistance values than controls. For irisin results, idiopathic infertility patients had significantly decreased values than controls indicating the potential effect of irisin in development of insulin resistance in idiopathic infertility patients. 相似文献
79.
Joseph K. Kendal Arvind Singla Asmaa Affan Kurt Hildebrand Abdullah Al-Ani Mark Ungrin Douglas J. Mahoney Doha Itani Frank R. Jirik Michael J. Monument 《Clinical orthopaedics and related research》2020,478(12):2921
BackgroundThe putative benefit of rhBMP-2 is in the setting of limb reconstruction using structural allografts, whether it be allograft-prosthetic composites, osteoarticular allografts, or intercalary segmental grafts. There are also potential advantages in augmenting osseointegration of uncemented endoprosthetics and in reducing infection. Recombinant human BMP-2 might mitigate nonunion in structural allograft augmented osteosarcoma limb salvage surgery; however, its use is limited because of concerns about the prooncogenic effects of the agent.Questions/purposes(1) To assess if BMP-2 signaling influences osteosarcoma cell line growth. (2) To characterize degree of osteosarcoma cell line osteoblastic differentiation in response to BMP-2. (3) To assess if BMP-2 signaling has a consistent effect on local or systemic tumor burden in various orthotopic murine models of osteosarcoma.MethodsIn this study, 143b, SaOS-2 and DLM8-M1 osteosarcoma cell lines were transfected with BMP-2 cDNA controlled by a constitutive promoter (experimental) or an empty vector (control) using a PiggyBac transposon system. Cellular proliferation was assessed using a quantitative MTT colorimetric assay. Osteoblastic differentiation was compared between control and experimental cell lines using quantitative real-time polymerase chain reaction of the osteoblastic markers connective tissue growth factor, Runx-2, Osterix, alkaline phosphatase and osteocalcin. Experimental and control cell lines were injected into the proximal tibia of either NOD-SCID (143b and SaOS-2 xenograft model), or C3H (DLM8-M1 syngeneic model) mice. Local tumor burden was quantitatively assessed using tumor volume caliper measurements and bioluminescence, and qualitatively assessed using post-mortem ex vivo microCT. Lung metastasis was qualitatively assessed by the presence of bioluminescence, and incidence was confirmed using histology. rhBMP-2 soaked absorbable collagen sponges (experimental) and sterile-H2O soaked absorbable collagen sponges (control) were implanted adjacent to 143b proximal tibial cell line injections to compare the effects of exogenous BMP-2 application with endogenous upregulation.ResultsConstitutive expression of BMP-2 increased the in vitro proliferation of 143b cells (absorbance values 1.2 ± 0.1 versus 0.89 ± 0.1, mean difference 0.36 [95% CI 0.12 to 0.6]; p = 0.01), but had no effect on SaOS-2 and DLM8-M1 cell proliferation. In response to constitutive BMP-2 expression, 143b cells had no differences in osteoblastic differentiation, while DLM8-M1 cells downregulated the early marker connective tissue growth factor (mean ΔCt 0.2 ± 0.1 versus 0.6 ± 0.1; p = 0.002) and upregulated the early-mid range marker Runx-2 (mean ΔCt -0.8 ± 0.1 versus -1.1 ± 0.1; p = 0.002), and SaOS-2 cells upregulated the mid-range marker Osterix (mean ΔCt -2.1 ± 0.6 versus -3.9 ± 0.6; p = 0.002). Constitutive expression of BMP-2 resulted in greater 143b and DLM8-M1 local tumor volume (143b: 307.2 ± 106.8 mm3 versus 1316 ± 387.4 mm3, mean difference 1009 mm3 [95% CI 674.5 to 1343]; p < 0.001, DLM8-M1 week four: 0 mm3 versus 326.1 ± 72.8 mm3, mean difference 326.1 mm3 [95% CI 121.2 to 531]; p = 0.009), but modestly reduced local tumor growth in SaOS-2 (9.5 x 108 ± 8.3x108 photons/s versus 9.3 x 107 ± 1.5 x 108 photons/s, mean difference 8.6 x 108 photons/s [95% CI 5.1 x 108 to 1.2 x 109]; p < 0.001). Application of exogenous rhBMP-2 also increased 143b local tumor volume (495 ± 91.9 mm3 versus 1335 ± 102.7 mm3, mean difference 840.3 mm3 [95% CI 671.7 to 1009]; p < 0.001). Incidence of lung metastases was not different between experimental or control groups for all experimental conditions.ConclusionsAs demonstrated by others, ectopic BMP-2 signaling has unpredictable effects on local tumor proliferation in murine models of osteosarcoma and does not consistently result in osteosarcoma cell line differentiation. Further investigations into other methods of safe bone and soft tissue healing augmentation and the use of differentiation therapies is warranted.Clinical RelevanceOur results indicate that BMP-2 has the potential to stimulate the growth of osteosarcoma cells that are poorly responsive to BMP-2 mediated osteoblastic differentiation. As this differentiation potential is unpredictable in the clinical setting, BMP-2 may promote the growth of microscopic residual tumor burden after resection. Our study provides further support for the recommendation to avoid the use of BMP-2 after limb-salvage surgery in patients with osteosarcoma. 相似文献