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排序方式: 共有374条查询结果,搜索用时 15 毫秒
61.
Roussa E Oehlke O Rahhal B Heermann S Heidrich S Wiehle M Krieglstein K 《Stem cells (Dayton, Ohio)》2008,26(7):1683-1694
The aim of the present study was to investigate the putative cooperative effects of transforming growth factor beta (TGF-beta) and glial cell line-derived neurotrophic factor (GDNF) family ligands in the differentiation of midbrain progenitors toward a dopaminergic phenotype. Therefore, a mouse midbrain embryonic day (E) 12 neurospheres culture was used as an experimental model. We show that neurturin and persephin (PSPN), but not GDNF, are capable of transient induction of dopaminergic neurons in vitro. This process, however, requires the presence of endogenous TGF-beta. In contrast, after 8 days in vitro GDNF rescued the TGF-beta neutralization-dependent loss of the TH-positive cells. In vivo, at E14.5, no apparent phenotype concerning dopaminergic neurons was observed in Tgf-beta2(-/-)/gdnf(-/-) double mutant mice. In vitro, combined TGF-beta/PSPN treatment achieved a yield of approximately 20% TH-positive cells that were less vulnerable against 1-methyl-4-phenyl pyridinium ion toxicity. The underlying TGF-beta/PSPN differentiation signaling is receptor-mediated, involving p38 mitogen-activated protein kinase and phosphatidylinositol 3-kinase pathways. These results indicate that phenotype induction and survival of fully differentiated neurons are accomplished through distinct pathways and individual factor requirement. TGF-beta is required for the induction of dopaminergic neurons, whereas GDNF is required for regulating and/or maintaining a differentiated neuronal phenotype. Moreover, this study suggests that the combination of TGF-beta with PSPN is a potent inductive cocktail for the generation of dopaminergic neurons that should be considered in tissue engineering and cell replacement therapies for Parkinson's disease. 相似文献
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Ahmed Esmael Mohamed Elsherif Mohamed Abdelsalam Dalia Sabry Mohamed Mamdouh Tamer Belal 《Neurological research》2020,42(7):564-574
ABSTRACT
Objectives
The purpose of this research is to predict the cognitive impairment and to determine its correlation with retinal thickness, mainly (RFNL and GCIPL) in cases of multiple sclerosis. 相似文献65.
Cumyl-CBMICA: A new synthetic cannabinoid receptor agonist containing a cyclobutyl methyl side chain
Sebastian Halter Benedikt Pulver Maurice Wilde Belal Haschimi Folker Westphal Jan Riedel Michael Pütz Torsten Schönberger Stefanie Stoll Jan Schäper Volker Auwärter 《Drug testing and analysis》2021,13(1):208-216
Since the beginning of the phenomenon of new psychoactive substances (NPS), synthetic cannabinoid receptor agonists (SCRAs) have been the largest and most prevalent subclass of these drugs in Europe. Many countries implemented specific legislation scheduling classes of substances defined on the basis of their chemical structure to reduce supply. We describe the identification and analytical characterization within the EU project ADEBAR plus of 1-(cyclobutylmethyl)-N-(2-phenylpropan-2-yl)-1H-indole-3-carboxamide which resulted in the formal notification through the Early Warning System of the European Monitoring Centre for Drug and Drug Addiction (EMCDDA). This is the first identification of this new SCRA worldwide and the analytical data was distributed (inter-)nationally right after identification in 2019. First, the substance was isolated from the herbal material using preparative high-performance liquid chromatography (HPLC). Structure elucidation and analytical characterization were performed using gas chromatography–mass spectrometry (GC–MS), gas chromatography-solid state infrared spectroscopy (GC-sIR), liquid chromatography-electrospray ionization-quadrupole time of flight-mass spectrometry (LC-ESI-qToF-MS), Raman spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The new compound contains a cyclobutyl methyl group as a side chain and has not been described in any patent to our knowledge. Based on the semisystematic nomenclature of SCRAs, we propose Cumyl-CBMICA as a short name for the compound. 相似文献
66.
Tania Jain Mohamad Bassam Sonbol Belal Firwana Kantha R. Kolla Diana Almader-Douglas Jeanne Palmer Rafael Fonseca 《Biology of blood and marrow transplantation》2019,25(2):239-247
Autologous stem cell transplantation (SCT) is the standard of care for all transplantation-eligible patients diagnosed with multiple myeloma (MM). Various studies have compared clinical outcomes with frontline SCT (“early SCT”) versus standard-dose therapy (SDT) alone, with or without salvage SCT (“SDT/late SCT”). In this meta-analysis, we compare overall survival (OS) and progression-free survival (PFS) outcomes between these 2 treatment approaches. Twelve studies were identified, including a total of 3633 patients, of whom 1811 received early SCT and 1822 received SDT/late SCT. In our analysis of all 12 studies, OS was not significantly different between the 2 groups (hazard ratio [HR], .86; 95% confidence interval [CI], .70 to 1.04), but PFS was better with early SCT (HR, .67; 95% CI, .54 to .82). In a subgroup analysis of 3 studies in which novel agents were used for induction, OS again was similar in the 2 groups, and PFS was favorable with early SCT (HR, .50; 95% CI, .36 to .70). This analysis shows that over the years, early SCT has been associated with prolonged PFS, but this did not consequently translate into prolonged OS in patients with newly diagnosed MM. The benefit of early SCT in terms of OS is less clear in the era of novel agents, given the limited follow-up of these studies. 相似文献
67.
A Belal E Salah W Hajjar M El-Foudeh M Memon A Ezzat K Al-Kattan 《The Journal of cardiovascular surgery》2001,42(6):835-840
BACKGROUND: A retrospective study and analysis was performed to determine the value and benefit of pulmonary metastatectomy for soft tissue sarcomas, and which factors predict prognosis following resection. METHODS: Twenty-three patients underwent resections for pulmonary metastases from a soft tissue sarcoma (STS) at King Faisal Specialist Hospital and Research Center (KFSH&RC), between January 1985 and December 1998. There were 11 male and 12 female patients. Thirteen of 23 patients (57%) had one to three metastases, and 10 (43%) had four or more metastases. A total of 41 thoracic explorations was performed for the 23 evaluable patients. Median sternotomy was used only for three patients and lateral thoracotomy was used for 20 patients as an initial surgical approach. Pulmonary resections performed included one or more wedge resections (n=16), segmentectomy (n=5), and lobectomy (n=2). No one in this series underwent pneumonectomy. The number of resected metastatic nodules ranged from one-six with average three. Eight patients (35%) received various kinds of postoperative adjuvant chemotherapy. RESULTS: The overall and disease-free survival rate post-metastatectomy at five years was 24% and 21%, respectively. Various prognostic indicators were examined to evaluate their association with improved survival. Age, sex localization of the primary site and histologic type, tumor grade, size of the resected nodules, laterality (unilateral or bilateral), types of resection, adjuvant chemotherapy, and local recurrence did not significantly affect survival. However, patient with disease free interval >6 months, and those with three or fewer metastases showed a trend toward a higher five-year overall survival (p=0.06, 0.07, respectively). CONCLUSIONS: Surgical excision of lung metastases from soft tissue sarcomas is well accepted and should be considered as a first line of treatment if preoperative evaluation indicated that complete resection of the metastases is possible. Further investigation is needed before chemotherapy can be recommended as additional therapy. 相似文献
68.
Mitsuko Nakashima MD PhD Mitsuhiro Kato MD PhD Kazushi Aoto DDS PhD Masaaki Shiina MD PhD Hazrat Belal MS Souichi Mukaida MD PhD Satoko Kumada MD PhD Atsushi Sato MD PhD Ayelet Zerem MD PhD Tally Lerman‐Sagie MD Dorit Lev MD PhD Huey Yin Leong MD Yoshinori Tsurusaki PhD Takeshi Mizuguchi MD PhD Satoko Miyatake MD PhD Noriko Miyake MD PhD Kazuhiro Ogata MD PhD Hirotomo Saitsu MD PhD Naomichi Matsumoto MD PhD 《Annals of neurology》2018,83(4):794-806
69.
Omar Malik Sherif Saleh Belal Suleiman Bilal Ashqar Amita Maibam Maria Yaseen Amro Elrefaei Abigail Hines Virgilius Cornea Amr El-Husseini Xiaonan Mei Roberto Gedaly Ana Lia Castellanos Thomas Waid 《Transplantation proceedings》2019,51(6):1801-1809
BK viremia (BKV) is a recognized and potentially serious problem in renal transplantation. The risk factors and the impact of BKV on renal allograft and patient survival are controversial. This study reports an 8-year, single-center experience on the prevalence, risk factors, and outcomes of BKV in kidney transplant recipients. This is a retrospective analysis of all patients who received a kidney transplant at the University of Kentucky and had BK viral titers available from 2009 to 2017. BKV was defined by a polymerase chain reaction viral load of ≥ 10,000 copies per mL. Demographic, clinical, and laboratory data generated during routine outpatient follow up and inpatients records were collected. Independent risk factors for BKV were determined using uni- and multivariate analysis. Graft and patient survival was compared using Kaplan-Meier analysis, and the severity of polyomavirus nephropathy on biopsy was scored using the Banff 2017 classification. We identified 122 BK positive (19%) and 527 BK negative (81%) patients. BKV developed after a median of 115 days (range, 80–249 days) following kidney transplantation. The 1-, 5-, and 10-year graft survival was 97%, 75%, and 33% in the BKV group and 96%, 85%, and 71% in the BK negative group, respectively. Likewise, the 1-, 5-, and 10-year patient survival was 98%, 84%, and 52% in the BKV group and 98%, 92%, and 84% in the BK negative group. Male sex, age at transplantation, maintenance steroids, and alemtuzumab induction were associated with developing BKV in the multivariate analysis. We concluded that BKV is not uncommon after renal transplantation. The determinants for BKV are male sex, older transplant recipients, and maintenance steroids. BKV adversely affected graft and patient survival. A unified approach for BKV and polyomavirus nephropathy treatment is needed. 相似文献
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