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81.
Taghrid M. Gaafar Hala A. Abdel Rahman Wael Attia Hala S. Hamza Konrad Brockmeier Rabab E. El Hawary 《Clinical and experimental medicine》2014,14(2):177-184
Adult peripheral blood contains a limited number of endothelial progenitor cells that can be isolated for treatment of ischemic diseases. The adipose tissue became an interesting source of stem cells for regenerative medicine. This study aimed to investigate the phenotype of cells obtained by culturing adipose-derived mesenchymal stem cells (ad-MSCs) in the presence of endothelial growth supplements compared to endothelial cells obtained from umbilical cord blood (UCB). Passage 3 ad-MSCs and mononuclear layer from UCB were cultured in presence of endothelial growth media for 3 weeks followed by their characterization by flow cytometry and polymerase chain reaction. After culture in endothelial inductive media, ad-MSCs expressed endothelial genes and some endothelial marker proteins as CD31 and CD34, respectively. Adipose tissue could be a reliable source for easy obtaining, expanding and differentiating MSCs into endothelial-like cells for autologous cell-based therapy. 相似文献
82.
The objective of the present study was to determine the effect of the transportation stress on water buffalo calves. A total of 50 buffalo calves (8?±?1 months old, 165?±?13 kg) were assigned to one of two equal groups; the first group represented clinically healthy non-transported calves (control non-transported group; n?=?25) whereas calves of the second group were subjected to transportation (transported group; n?=?25). Blood samples were collected from control non-transported calves and from transported calves immediately after unloading (post-transportation). The present findings indicated that the examined hematological and biochemical parameters were not significantly (P?≤?0.05) changed in transported calves when compared with the control non-transported group. Furthermore, serum concentration of the investigated acute-phase proteins (APP) namely, haptoglobin (0.37?±?0.01), serum amyloid A (75.43?±?2.11), and fibrinogen (7.51?±?0.25) were significantly (P?≤?0.05) higher in transported calves when compared with control calves (0.1?±?0.01 g/l, 23.9?±?0.56 mg/l, and 4.2?±?0.16 g/l), respectively. Lipid peroxidation represented as malonaldhyde (56.78?±?3.42) was higher significantly (P?≤?0.05), whereas antioxidant biomarkers in the form of nitric oxide (17.68?±?0.89) levels, and activities of superoxide dismutase (7.37?±?0.53) and reduced glutathione (5.25?±?0.95) were lower significantly (P?≤?0.05) in the serum of transported calves when all were compared with the control group (24.68?±?0.19 nmol/g Hb, 21.80?±?0.24 mmol/ml, 9.24?±?0.1 U/g Hb, and 7.23?±?0.21 mmol/l), respectively. Conclusively, the present study demonstrated that transportation were significantly enough to trigger changes in APP and oxidative stress biomarkers in buffalo calves. 相似文献
83.
84.
Mohamed H. Hekal Abeer M. El-Naggar Fatma S. M. Abu El-Azm Wael M. El-Sayed 《RSC advances》2020,10(7):3675
Background and aim: The current study reports the synthesis and biological evaluation of two novel series of 4-(5-mercapto-1,3,4-oxadiazol-2-yl)phthalazin-1(2H)-one derivatives. Methods: The synthetic reactions were carried out under both conventional and ultrasonic irradiation conditions. The anti-proliferative activity of the newly synthesized compounds against two human epithelial cell lines; liver (HepG2) and breast (MCF-7) in addition to normal fibroblasts (WI-38) was investigated. In addition to molecular docking studies, the possible mechanism(s) of action were also explored. Results: In general, an improvement in synthetic rates and yields was observed when reactions were carried out under sonication compared with classical conditions. The structures of the products were established based on analytical and spectral data. Derivatives 2e and 7d, in addition to compound 1, had significant and selective anti-proliferative activity against liver and breast cancer cell lines without harming normal fibroblasts. These derivatives arrested the cell cycle progression and/or induced apoptosis. This has been manifested by the elevation in the expression of p53 and caspase 3, down-regulation of cdk1, and a reduction in the concentrations of MAPK and Topo II at submicromolar concentrations. The latter results confirmed the molecular docking study. Conclusions: Compound 1 had the best profile on the gene and protein levels (arresting cell cycle and inducing apoptosis). The ability of compounds 1 and 2e to inhibit both MAPK and Topo II nominates these derivatives as potential candidates for further anticancer and antitumor studies.The current study reports the synthesis and biological evaluation of two novel series of 4-(5-mercapto-1,3,4-oxadiazol-2-yl)phthalazin-1(2H)-one derivatives. 相似文献
85.
Moudhi Alroomi Rajesh Rajan Ahmad Alsaber Jiazhu Pan Mohammed Abdullah Hassan Abdelnaby Wael Aboelhassan Noor AlNasrallah Bader AlBader Haya Malhas Maryam Ramadhan Soumoud Hussein Naser Alotaibi Mohammad Al Saleh Kobalava D. Zhanna Farah Almutairi 《Journal of clinical laboratory analysis》2022,36(4)
BackgroundThis study investigates in‐hospital mortality amongst patients with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and its relation to serum levels of gamma‐glutamyl transferase (GGT).MethodsPatients were stratified according to serum levels of gamma‐glutamyl transferase (GGT) (GGT<50 IU/L or GGT≥50 IU/L).ResultsA total of 802 participants were considered, amongst whom 486 had GGT<50 IU/L and a mean age of 48.1 (16.5) years, whilst 316 had GGT≥50 IU/L and a mean age of 53.8 (14.7) years. The chief sources of SARS‐CoV‐2 transmission were contact (366, 45.7%) and community (320, 40%). Most patients with GGT≥50 IU/L had either pneumonia (247, 78.2%) or acute respiratory distress syndrome (ARDS) (85, 26.9%), whilst those with GGT<50 IU/L had hypertension (141, 29%) or diabetes mellitus (DM) (147, 30.2%). Mortality was higher amongst patients with GGT≥50 IU/L (54, 17.1%) than amongst those with GGT<50 IU/L (29, 5.9%). More patients with GGT≥50 required high (83, 27.6%) or low (104, 34.6%) levels of oxygen, whereas most of those with GGT<50 had no requirement of oxygen (306, 71.2%). Multivariable logistic regression analysis indicated that GGT≥50 IU/L (odds ratio [OR]: 2.02, 95% confidence interval [CI]: 1.20–3.45, p=0.009), age (OR: 1.05, 95% CI: 1.03–1.07, p<0.001), hypertension (OR: 2.06, 95% CI: 1.19–3.63, p=0.011), methylprednisolone (OR: 2.96, 95% CI: 1.74–5.01, p<0.001) and fever (OR: 2.03, 95% CI: 1.15–3.68, p=0.016) were significant predictors of all‐cause cumulative mortality. A Cox proportional hazards regression model (B = −0.68, SE =0.24, HR =0.51, p = 0.004) showed that patients with GGT<50 IU/L had a 0.51‐times lower risk of all‐cause cumulative mortality than patients with GGT≥50 IU/L.ConclusionHigher levels of serum GGT were found to be an independent predictor of in‐hospital mortality. 相似文献
86.
Maha H. Hussain M.D. Isaac Powell M.D. Nagi Zaki M.D. M.S. Zocia Maciorowski M.S. Wael Sakr M.D. Mark Kukuruga B.S. Daniel Visscher M.D. Gabriel P. Haas M.D. J. Edson Pontes M.D. John F. Ensley M.D. 《Cancer》1993,72(10):3012-3019
Background. DNA ploidy analysis has been investigated as a prognostic indicator in prostate cancer. Most of the data is derived from retrospective studies using paraffin-embedded tissue. This method has drawbacks related to the quality of DNA histograms and uncontrolled data collection. Methods. DNA ploidy analysis of freshly resected prostatic tissue was prospectively compared with conventional prognostic variables in 97 men treated with radical prostatectomy for localized prostate cancer. Results. Regarding the patients, 31.9% were African American and 66% had pathologic Stages C or D1 disease. Only 9.6% of patients with Stages A2 and B had a prostate-specific antigen (PSA) value greater than 10 ng/ml, whereas 97% of patients with PSA values greater than 20 ng/ml had pathologic Stages C and D1. PSA levels correlated with Gleason score (P = < 0.05); 51% and 100% of patients with Gleason score 5–7 and 8–10, respectively, had PSA values greater than 10 ng/ml. Twenty-two patients (23%) had DNA aneuploid tumors. Comparisons of mechanical to enzymatic cell suspensions indicated that DNA aneuploidy was better preserved in mechanical cell preparations. DNA ploidy correlated with pathologic stage (P = < 0.05) and Gleason score (P = < 0.05). Fifteen of 79 patients (18.9%) with Gleason score 5–7 had DNA aneuploid tumors versus 71.4% of patients with Gleason score 8–10. PSA groups correlated with ploidy status (P = 0.01). Although the majority of patients (19 of 22) with DNA aneuploid tumors had elevated preoperative PSA levels, none had a PSA value greater than 50 ng/ml. Conclusions. DNA ploidy analysis correlated with established prognostic indicators in prostate cancer; however, its independent correlation with natural history and treatment outcome must be established for it to have an effect on therapeutic decisions. 相似文献
87.
88.
Use of a curved-array transducer to reduce interobserver variation in sonographic measurement of thyroid volume in healthy adults 总被引:1,自引:0,他引:1
Peeters EY Shabana WM Verbeek PA Osteaux MM 《Journal of clinical ultrasound : JCU》2003,31(4):189-193
PURPOSE: Sonographic calculation of thyroid volume is used in the diagnosis and follow-up of thyroid diseases. Since the calculated volume of thyroid lobes is highly influenced by the longest (ie, craniocaudal) diameter, we examined whether using a curved-array transducer as opposed to a linear-array transducer to measure the craniocaudal diameter would reduce interobserver variation. METHODS: Three sonographers with different levels of expertise each used a 5-12-MHz linear-array transducer and a 2-5-MHz curved-array transducer to measure the craniocaudal diameter of both thyroid lobes of 25 healthy volunteers. On the basis of these measurements, thyroid lobe volumes were calculated. Single-factor analysis of variance was used to evaluate the interobserver variations between the measurements made by all 3 observers as well as between measurements taken by pairs of observers. A p value of less than 0.05 was considered significant. RESULTS: Using the linear-array transducer to measure the craniocaudal diameter resulted in significant interobserver variation in thyroid volume calculation (p = 0.02), whereas using the convex-array transducer did not. Using either transducer resulted in a highly significant interobserver variation in measurements of the craniocaudal diameter, although the variation was far more pronounced for measurements made with the linear-array transducer (p = 0.0005) than for those made with the curved-array transducer (p = 0.04). For both transducers, the interobserver variations were most pronounced between the most and the least experienced sonographers. CONCLUSIONS: To avoid significant interobserver variation in calculating thyroid lobe volume, we recommend using a curved-array transducer to measure the craniocaudal diameter of the thyroid lobes. 相似文献
89.
90.
Alessandra DAmico Elena Cavarretta Chiara Fossati Paolo Borrione Fabio Pigozzi Giacomo Frati Sebastiano Sciarretta Vincenzo Costa Fabrizio De Grandis Antonia Nigro Mariangela Peruzzi Fabio Miraldi Wael Saade Antonella Calogero Paolo Rosa Gioacchino Galardo Lorenzo Loffredo Pasquale Pignatelli Cristina Nocella Roberto Carnevale 《Nutrients》2022,14(8)
Mechanisms of exercise-induced muscle injury with etiopathogenesis and its consequences have been described; however, the impact of different intensities of exercise on the mechanisms of muscular injury development is not well understood. The aim of this study was to exploit the relationship between platelet activation, oxidative stress and muscular injuries induced by physical exercise in elite football players compared to amateur athletes. Oxidant/antioxidant status, platelet activation and markers of muscle damage were evaluated in 23 elite football players and 23 amateur athletes. Compared to amateurs, elite football players showed lower antioxidant capacity and higher oxidative stress paralleled by increased platelet activation and muscle damage markers. Simple linear regression analysis showed that sNOX2-dp and H2O2, sCD40L and PDGF-bb were associated with a significant increase in muscle damage biomarkers. In vitro studies also showed that plasma obtained from elite athletes increased oxidative stress and muscle damage in human skeletal muscle myoblasts cell line compared to amateurs’ plasma, an effect blunted by the NOX2 inhibitor or by the cell treatment with cocoa-derived polyphenols. These results indicate that platelet activation increased muscular injuries induced by oxidative stress. Moreover, NOX2 inhibition and polyphenol extracts treatment positively modulates redox status and reduce exercise-induced muscular injury. 相似文献