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11.
Seyed Mojtaba Hosseini Attiyeh Vasaghi Newsha Nakhlparvar Reza Roshanravan Tahereh Talaei-khozani Zahra Razi 《中国神经再生研究》2015,10(8):1312-1316
Alginate scaffold has been considered as an appropriate biomaterial for promoting the differentiation of embryonic stem cells toward neuronal cell lineage. We hypothesized that alginate scaffold is suitable for culturing Wharton's jelly mesenchymal stem cells(WJMSCs) and can promote the differentiation of WJMSCs into neuron-like cells. In this study, we cultured WJMSCs in a three-dimensional scaffold fabricated by 0.25% alginate and 50 m M Ca Cl2 in the presence of neurogenic medium containing 10 μM retinoic acid and 20 ng/m L basic fibroblast growth factor. These cells were also cultured in conventional two-dimensional culture condition in the presence of neurogenic medium as controls. After 10 days, immunofluorescence staining was performed for detecting β-tubulin(marker for WJMSCs-differentiated neuron) and CD271(motor neuron marker). β-Tubulin and CD271 expression levels were significantly greater in the WJMSCs cultured in the three-dimensional alginate scaffold than in the conventional two-dimensional culture condition. These findings suggest that three-dimensional alginate scaffold cell culture system can induce neuronal differentiation of WJMSCs effectively. 相似文献
12.
Seyed Mojtaba Hosseini Mohammad Farahmandnia Zahra Razi Somayeh Delavarifar Benafsheh Shakibajahromi 《中国神经再生研究》2015,10(6):904-908
Cell therapy using stem cell transplantation against cerebral ischemia has been reported. However, it remains controversial regarding the optimal time for cell transplantation and the transplantation route. Rat models of cerebral ischemia were established by occlusion of the middle cerebral artery. At 1, 12 hours, 1, 3, 5 and 7 days after cerebral ischemia, bone marrow mesenchymal stem cells were injected via the tail vein. At 28 days after cerebral ischemia, rat neurological function was evaluated using a 6-point grading scale and the pathological change of ischemic cerebral tissue was observed by hematoxylin-eosin staining. Under the fluorescence microscope, the migration of bone marrow mesenchymal stem cells was examined by PKH labeling. Caspase-3 activity was measured using spectrophotometry. The optimal neurological function recovery, lowest degree of ischemic cerebral damage, greatest number of bone marrow mesenchymal stem cells migrating to peri-ischemic area, and lowest caspase-3 activity in the ischemic cerebral tissue were observed in rats that underwent bone marrow mesenchymal stem cell transplantation at 12 hours after cerebral ischemia. These findings suggest that 12 hours after cerebral ischemia is the optimal time for tail vein injection of bone marrow mesenchymal stem cell transplantation against cerebral ischemia, and the strongest neuroprotective effect of this cell therapy appears at this time. 相似文献
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Koji Park John N. Afthinos Syed S. Razi Elaine Chan David Y. Lee Julio A. Teixeira 《Surgery for obesity and related diseases》2013,9(5):686-691
BackgroundLaparoendoscopic single-site (LESS) surgery has been shown to be a well-tolerated alternative for the placement of an adjustable gastric band. To date, only small series have suggested that this approach may provide potential clinical benefits over standard multiport laparoscopy. The objective of this study was to compare the outcomes of patients undergoing LESS adjustable gastric banding (LESS-AGB) and a cohort of patients undergoing standard multiport laparoscopic adjustable gastric banding (LAGB).MethodsA total of 206 patients underwent placement of an adjustable gastric band. Of these, 106 patients underwent LESS-AGB and were compared with a demographically similar cohort of 100 patients who underwent standard LAGB. Data collected included operative time, parenteral and oral narcotic consumption, duration of patient controlled analgesia (PCA) device, subjective pain scores using the 0–10 numeric pain intensity scale, and length of stay. Unpaired t test was used for analysis.ResultsCompared with multiport LAGB patients, LESS-AGB patients reported significantly less pain at the first postoperative hour (P = .012), twelfth postoperative hour (P = .017), and twenty-fourth postoperative hour (P = .012), and consumed fewer oral analgesic tablets (P = .012). Operative times were significantly longer in the LESS-AGB group (P = .029). No significant differences were seen in duration of PCA, parenteral narcotic consumption, or length of stay. One LESS-AGB case required conversion to multiport laparoscopy. Complication rates were similar between the 2 groups.ConclusionLESS-AGB is associated with less pain and less oral analgesic consumption than multiport LAGB. Given these clinical advantages and superior cosmetic results, laparoendoscopic single-site surgery may be an attractive alternative approach for patients considering LAGB. (Surg Obes Relat Dis 2013;0;000–00.) © 2013 American Society for Metabolic and Bariatric Surgery. All rights reserved. 相似文献
18.
Kamrul Hasan Shivakumar Shankar Aadhar Sharma Alison Carter Razi Zaidi Suzie Cro John Skinner Andy Goldberg 《Journal of orthopaedics and traumatology》2016,17(4):291-295
Background
The burden of traumatic and elective hip surgery is set to grow. With an increasing number of techniques and implants against the background of an aging population, the emphasis on evidence-based treatment has never been greater. The purpose of this study was to assess changes in the levels of evidence in the hip literature over a decade.Materials and methods
Articles pertaining to hip surgery from the years 2000 and 2010 in Hip International, Journal of Arthroplasty, Journal of Bone and Joint Surgery and The Bone and Joint Journal were analysed. Articles were ranked by a five-point level of evidence scale and by type of study, according to guidelines from the Centre for Evidence-based Medicine.Results
531 articles were analysed from 48 countries. The kappa value for the inter-observer reliability showed excellent agreement between the reviewers for study type (κ = 0.956, P < 0.01) and for levels of evidence (κ = 0.772, P < 0.01). Between 2000 and 2010, the overall percentage of high-level evidence (levels I and II) studies more than doubled (12 to 31 %, P < 0.001). The most frequent study type was therapeutic; the USA and UK were the largest producers of published work in these journals, with contributions from other countries increasing markedly over the decade.Conclusions
There has been a significant increase in high levels of evidence in hip surgery over a decade (P < 0.001). We recommend that all orthopaedic journals consider implementing compulsory declaration by authors of the level of evidence to help enhance quality of evidence.Level of evidence
Level 2: economic and decision analysis.19.
Mahmoud MAHAMI OSKOUEI Esmaeil FALLAH Mahmoud AHMADI Abdolrasoul SAFAIYAN Salar BAKHTIYARI Razi NASERIFAR Majid DOUSTI 《Iranian Journal of Parasitology》2014,9(3):435-440
Background
Cryptosporidiosis is one of the most important parasitic infections in human and animals. This study was designed for survey on the prevalence of Cryptosporidium infection in farms of Ilam, west of Iran, using parasitology method and genotyping by Nested PCR-RFLP.Methods
Fecal samples of 217 cattle were collected fresh and directly from the rectum of cattle. All of the samples were examined by microscopic observation after staining with modified Ziehl-Neelsen (MZN). Genomic DNA extracted by using EURx DNA kit. A Nested PCR-RFLP protocol amplifying 825 bp fragment of 18s rRNA gene conducted to differentiate species and genotyping of the isolates using SspI and VspI as restriction enzymes.Results
The prevalence of Cryptosporidium infection in cattle using both methods is 3.68%. Most of the positive cattle were calves under six months. Species diagnosis carried out by digesting the secondary PCR product with SspI that C. parvum generated 3 visible bands of 448, 247 and 106 bp and digested by VspI restriction enzyme generated 2 visible bands of 628 and 104bp. In this investigation all of the positive samples were Cryptosporidium parvum.Conclusion
C. parvum (bovine genotype) detected in all positive cattle samples in Ilam, west of Iran. The results of the present study can help for public health care systems to prevention and management of cryptosporidiosis in cattle and the assessment of cattle cryptosporidiosis as a reservoir for the human infection. 相似文献20.
Rodiansono Maria Dewi Astuti Kamilia Mustikasari Sadang Husain Fathur Razi Ansyah Takayoshi Hara Shogo Shimazu 《RSC advances》2021,12(1):241
Bimetallic Ni–Sn alloys have been recognised as promising catalysts for the transformation of furanic compounds and their derivatives into valuable chemicals. Herein, we report the utilisation of a supported bimetallic RANEY® nickel–tin alloy supported on aluminium hydroxide (RNi–Sn(x)/AlOH; x is Ni/Sn molar ratio) catalysts for the one-pot conversion of biomass-derived furfural and levulinic acid to 1,4-pentanediol (1,4-PeD). The as prepared RNi–Sn(1.4)/AlOH catalyst exhibited the highest yield of 1,4-PeD (78%). The reduction of RNi–Sn(x)/AlOH with H2 at 673–873 K for 1.5 h resulted in the formation of Ni–Sn alloy phases (e.g., Ni3Sn and Ni3Sn2) and caused the transformation of aluminium hydroxide (AlOH) to amorphous alumina (AA). The RNi–Sn(1.4)/AA 673 K/H2 catalyst contained a Ni3Sn2 alloy as the major phase, which exhibited the best yield of 1,4-PeD from furfural (87%) at 433 K, H2 3.0 MPa for 12 h and from levulinic acid (up to 90%) at 503 K, H2 4.0 MPa, for 12 h. Supported RANEY® Ni–Sn(1.5)/AC and three types of supported Ni–Sn(1.5) alloy (e.g., Ni–Sn(1.5)/AC, Ni–Sn(1.5)/c-AlOH, and Ni–Sn(1.5)/γ-Al2O3) catalysts afforded high yields of 1,4-PeD (65–87%) both from furfural and levulinic acid under the optimised reaction conditions.The RANEY® Ni–Sn(x) alloy catalysed the one-pot conversion of biomass-derived furfural and levulinic acid to allow remarkable yield of 1,4-pentanediol (up to 90%) under the mild reaction conditions. 相似文献