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31.
Under specific culture conditions, umbilical cord blood derived mesenchymal stem cells (MSCs) can differentiate into osteogenic, adipogenic, and chondrogenic lineages. The purpose of the current study was to assess the differentiation potential of osteogenic umbilical cord blood derived hematopoietic stem cells (HSCs) and to develop an appropriate osteogenic differentiation medium for in vitro differentiation of umbilical cord blood derived HSCs. The study was conducted on 20 cord blood samples. The cells were cultured in osteogenic differentiating medium for 3?weeks. The HSCs differentiated into osteoblasts, which expressed osteoblast-associated genes (osteocalcin and bone sialoprotein), which were detected by RT-PCR. They showed alkaline phosphatase activity and a positive Alizarin red-S (AR-S) stain (calcium phosphate deposition). Umbilical cord blood is a rich source of hematopoietic stem cells that can be differentiated into osteoblasts; thus, it can be used for therapeutic strategies in the context of regenerative therapy.  相似文献   
32.
Objectives: Measurement of salivary progesterone (SP4) levels and cervical length (CL) after 24 weeks to assess their potential predictive value among asymptomatic women at high risk of spontaneous preterm birth (PTB).

Methods: This prospective observational (noninterventional) study consecutively recruited asymptomatic women at high risk of spontaneous PTB. SP4 and CL were measured at recruitment (24–28 weeks of gestation) then repeated after 3–4 weeks. All recruited women were followed up regularly till delivery. The primary outcome measure was the occurrence of spontaneous PTB.

Results: One hundred and thirty four women completed the study, 22 (16.4%) and 32 (23.9%) women had early (<34 weeks) and late (≥34 weeks) PTB, respectively. Initially, the mean CL was 3.2?±?0.6?cm and the mean SP4 was 4062.8?±?814.6?pg/ml; with follow up, the mean CL became 3.0?±?0.6?cm and the mean SP4 became 3871.6?±?1136.9. Women with early PTB had significantly lower initial and follow up CL and SP4 measures when compared to women with late PTB and those who had birth at term. The rate of drop in SP4 and CL measurements between the two visits was also significantly higher among women with early PTB than those with late PTB and term birth. Receiver-operating characteristic (ROC) curves showed that, CL was a good predictor but SP4 was a better predictor of PTB as the area under the curve (AUC) for CL was less than that for SP4 at both visits (i.e. 0.858 and 0.868 versus 0.986 and 0.990 at the initial and follow up visits, respectively). There was a statistically significant correlation between CL and SP4 measurements. Multivariable binary logistic regression analysis revealed that follow up SP4 measurement was the only independent predictor of spontaneous PTB, and neither BMI, maternal age, SP4 nor CL were independent predictors of early spontaneous PTB.

Conclusions: After 24 gestational weeks, SP4 assessment is a simple and reliable promising tool to predict spontaneous PTB among asymptomatic high-risk women, with a little superior performance than CL measurement.  相似文献   
33.

Background

Clear cell renal cell carcinoma (cc-RCC), is a serious cancer regarding; its fatality, liability for metastases and chemoresistance, so identification of recent therapeutic targets to improve the patients prognosis is needed. SPOP is a BTB/POZ domain containing speckle-type POZ protein, has been identified as an E3 ubiquitin ligase component. ZEB1 is an essential epithelial mesenchymal transition (EMT) activator; E-cadherin is a cell adhesion protein that had been detected in normal epithelial cells membrane.

Aim

Was to assess the tissue protein markers SPOP, ZEB1 & E-cadherin expressions in benign areas of neoplastic kidney specimens and in cc-RCC patients, then correlating their expression levels with patients clinicopathological and prognostic data.

Methods

We evaluated SPOP, ZEB-1 & E-cadherin expression using immunohistochemistry in samples from 50 cc-RCC and 20 benign areas of neoplastic kidney specimens, then we followed our patients for 5 years and finally we have analyzed correlations between the levels of markers expressions with patients clinicopathological and prognostic criteria in cc-RCC.

Results

Positive expression of SPOP & ZEB1 in addition to negative E- cadherin expression was detected in cc-RCC more than benign areas of neoplastic kidney specimens (p?=?0.004 and p?<?0.001 respectively). In cc-RCC Positive expression of SPOP, ZEB1 and negative E- cadherin expression was associated with higher grade (p?=?0.006, 0.007 & <0.001 respectively), advanced AJCC stage (p?=?0.013, 0.023 & <0.001 respectively), presence of L.N metastases (p?=?0.002?=?0.010 and <0.001 respectively), distant metastases (p?=?0.001, 0.003 & 0.035 respectively), poor PFS and OS rates (p?<?0.001 and p?=?0.013 respectively).

Conclusion

Positive expression of SPOP& ZEB1 in addition to negative E- cadherin are associated with poor prognosis in cc-RCC patients.  相似文献   
34.
Donor specific antibodies (DSA) play a significant role in graft rejection. Many laboratory methods, varied in sensitivity and specificity, are used to detect them. We report a case of a 38-year-old man presented with end stage renal disease considered for kidney transplantation. He had no history of blood transfusions nor transplantation procedures. Dilemma rose when he got multiple positive crossmatches with matching donors and a positive autologous crossmatch due to IgG anti HLA auto-antibodies, which are at the same time against matched donors. Since positive crossmatch is a contraindication for transplant, we couldn’t perform transplant from any matched donor. Therefore, we considered a total mismatched donor then transplantation was performed. Observation after surgery showed normalization of creatinine, blood pressure and a good function of the planted allograft for two years of follow up.  相似文献   
35.
Hydrophobic agents, a fluorescent dye (Nile red, NR) or an anticancer drug (doxorubicin, DOX), are encapsulated into poly((N‐[3‐(dimethylamino) propyl] methacrylamide)‐b‐poly (methyl methacrylate) (PDMAPMA‐b‐PMMA) nanoparticles (NPs) via one‐pot reversible addition‐fragmentation chain‐transfer (RAFT)‐mediated emulsion polymerization in water. The macroRAFT, PDMAPMA, is chain‐extended with the methyl methacrylate (MMA), with the hydrophobic agents soluble in MMA, resulting in loaded NPs, with either NR or DOX via polymerization‐induced self‐assembly (PISA). The NR‐loaded NPs are visualized by structured illumination microscopy (SIM), thus indicating the successful loading of the fluorescent dye into the PMMA core. The DOX‐loaded NPs exhibit a sustained release profile over 5 d, showing a small burst effect during the first 2 h, as compared with the free DOX. The DOX‐loaded NPs show higher cell toxicity than the free DOX in RAW 264.7 cell line. The results demonstrate the potential of using emulsion polymerization for synthesis of tailored and reproducible NPs encapsulating hydrophobic agents.  相似文献   
36.
37.
There is an increasing demand for age estimations of living persons who are involved in civil and criminal procedures but lack a valid birth certificate indicating their date of birth. Several studies have recommended the application of magnetic resonance imaging (MRI) and assessment of the stage of epiphyseal fusion in age estimation. This study involved retrospective MRI analysis of 335 cases (217 males and 118 females) whose ages ranged from 8 to 28 years (yrs). We assessed the degree of ossification of the proximal tibial epiphysis depending on the classifications of Schmeling and Kellinghaus used for the main stages (I, II, III, IV & V) and substages (IIa, b, c & IIIa, b, c). Significant differences between males and females at stages IIIc, IV and V (p < 0.001) were observed. Additionally, the ossification of the proximal tibial epiphyses occurred earlier in females than in males (2–4 yrs). The mean of ages in stage IV was approximately 18.6 yrs. in females and 22.5 yrs. in males, meaning that stage IV can be used as a valuable forensic marker to determine whether the person in question has reached the age of 18 yrs. We concluded that the application of MRI in the assessment of the ossification status of the proximal tibial epiphysis could be helpful in age estimation for various forensic purposes.  相似文献   
38.
39.
Soft tissue chondroma is an uncommon soft-tissue cartilaginous tumor of benign nature, it considers a variant of extra-skeletal chondromas that undergoes extensive ossification. This case of a 37?years old Egyptian male presented with a recurrent slowly growing painful palpable heel mass arises at the plantar aspect of his RT foot.The case is pathologically proven to be benign soft tissue chondroma.  相似文献   
40.
Numerous molecular mechanisms are being examined in an attempt to discover disease-modifying drugs to slow down the underlying neurodegeneration in Alzheimer’s disease.Recent studies have shown the beneficial effects of epidermal growth factor receptor inhibitors on the enhancement of behavioral and pathological sequelae in Alzheimer’s disease.Despite the promising effects of epidermal growth factor receptor inhibitors in Alzheimer’s disease,there is no irrefutable neuroprotective evidence in well-established animal models using epidermal growth factor receptor inhibitors due to many un-explored downstream signaling pathways.This caused controversy about the potential involvement of epidermal growth factor receptor inhibitors in any prospective clinical trial.In this review,the mystery beyond the under-investigation of epidermal growth factor receptor in Alzheimer’s disease will be discussed.Furthermore,their molecular mechanisms in neurodegeneration will be explained.Also,we will shed light on SARS-COVID-19 induced neurological manifestations mediated by epidermal growth factor modulation.Finally,we will discuss future perspectives and under-examined epidermal growth factor receptor downstream signaling pathways that warrant more exploration.We conclude that epidermal growth factor receptor inhibitors are novel effective therapeutic approaches that require further research in attempts to be repositioned in the delay of Alzheimer’s disease progression.  相似文献   
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