The POU family transcription factor OCT4 is required for maintaining the pluripotency of embryonic stem cells and for generating induced pluripotent stem cells. Although OCT4 is clearly shown to be expressed in some pluripotent germ cell tumours, its expression in human somatic tumours remains controversial. Some studies have shown that OCT4 is expressed in adult stem cells, somatic cancers and, further, cancer stem cells, while other studies failed to make such an observation. It is thus important to ascertain whether OCT4 is expressed in human somatic tumours. By using RT-PCR and sequencing analysis, three OCT4 pseudogenes, viz. OCT4-pg1, OCT4-pg3 and OCT4-pg4 but excluding the OCT4 gene, were found to be expressed in two types of human solid tumours, glioma and breast carcinoma, from which cancer stem cells had earlier been isolated. The protein expression of these pseudogenes was further demonstrated by immunochemistry and western blotting. Along with this, it was shown that OCT4 pseudogenes lacked OCT4-like activities. The expression of OCT4 splicing variant and various pseudogenes at both the mRNA and protein levels in human somatic tumours might call into question the reliability of the results regarding OCT4 expression and function in tumourigenesis. Hence, in investigations of OCT4 expression in cancers and stem cells, different approaches with appropriate controls would be desirable to exclude possibility of false-positive results.
In this paper,digital audio and video encoding technology standard(Audio Video Coding Standard,AVS)is used asthe basis,by analysing the search algorithm of motion vector,to make improvements for the part of full search algorithm,propose and realize the pattern splicing technology to strengthen the relevance between the search mode,at the same timeavoid multiple searches on the same area. The new full search program can handle full search cif and D1 format videosequences. Compared with the old program,the new program keep rate and PSNR basically unchanged,the processing speedimproved 300%. It has important significance for hardware implementation.
Abstract In contrast to mammals, adult zebrafish have the ability to regrow descending axons and gain locomotor recovery after spinal cord injury (SCI). In zebrafish, a decisive factor for successful spinal cord regeneration is the inherent ability of some neurons to regrow their axons via (re)expressing growth‐associated genes during the regeneration period. The nucleus of the medial longitudinal fascicle (NMLF) is one of the nuclei capable of regenerative response after SCI. Using microarray analysis with laser capture microdissected NMLF, we show that cysteine‐ and glycine‐rich protein (CRP)1a (encoded by the csrp1a gene in zebrafish), the function of which is largely unknown in the nervous system, was upregulated after SCI. In situ hybridization confirmed the upregulation of csrp1a expression in neurons during the axon growth phase after SCI, not only in the NMLF, but also in other nuclei capable of regeneration, such as the intermediate reticular formation and superior reticular formation. The upregulation of csrp1a expression in regenerating nuclei started at 3 days after SCI and continued to 21 days post‐injury, the longest time point studied. In vivo knockdown of CRP1a expression using two different antisense morpholino oligonucleotides impaired axon regeneration and locomotor recovery when compared with a control morpholino, demonstrating that CRP1a upregulation is an important part of the innate regeneration capability in injured neurons of adult zebrafish. This study is the first to demonstrate the requirement of CRP1a for zebrafish spinal cord regeneration.
Abstract Background: Between 2003 and 2009, there were approximately 20,000 brain deaths per million people per year in China.These cases represent an important source for organ donation. As it is neurologists who are primarily involved in determining brain death, their knowledge and attitude toward brain death and organ donation directly affects decisions of family members regarding organ donation. Methods: This qualitative study was conducted in 2019. Data on neurologists’ knowledge and attitudes towards brain death and organ donation were obtained from fifteen neurologists in the Departments of Neurology from Chinese hospitals using a content analysis approach as achieved in semi-structured interviews. Results: Overall, these neurologists conveyed a positive attitude toward organ donation after brain death. However, they noted the importance of considering and respecting the opinions of these patients’ families. From the data analysis, 4 themes and 12 categories were developed. The 4 themes included: 1) brain death organ donation as a good thing, 2) interacting with brain death patient’s family, 3) cultural influences on organ donation with brain death and 4) strategies to improve organ donation rates in patients with brain death. Conclusion: The results of this study have provided some new and important information regarding the knowledge and attitude of Chinese neurologists toward brain death and organ donation. Such information is critical for guiding government and health care systems in designing strategies to improve donation rates and decisions from brain death patients.
Guo Y, Liu S, Wang P, Zhao S, Wang F, Bing L, Zhang Y, Ling E-A, Gao J & Hao A(2011) Histopathology59, 763–775 Expression profile of embryonic stem cell-associated genes Oct4, Sox2 and Nanog in human gliomas Aims: To investigate whether Oct4, Sox2 and Nanog, three core regulatory factors maintaining pluripotency and self-renewal of embryonic stem cells (ESCs), are coexpressed in human gliomas, and whether their expression might be linked to carcinogenesis and the formation of cancer stem cells (CSCs). Methods and results: Forty cases of human glioma were examined. The expression of Oct4, Sox2 and Nanog was analysed by immunohistochemistry, reverse transcription polymerase chain reaction and western blot. We found a positive correlation between the expression levels of Oct4, Sox2 and Nanog and tumour malignancy. Immunohistochemistry showed that Oct4 and Nanog were expressed in both the nuclei and the cytoplasm of glioma cells, whereas Sox2 was expressed only in the nuclei. Double immunofluorescence staining revealed that a majority of Oct4-positive cells coexpressed Sox2 and Nanog. More than 50% of Oct4-positive cells coexpressed the putative CSC markers CD133 and Nestin. Moreover, some cells exhibited Oct4 and Nanog immunoexpression in the cytoplasm, but the frequency of positive cells did not correlate with tumour malignancy. Conclusions: The present findings suggest that ESC-associated pathways are activated in human gliomas and that these may be involved in glioma progression, a role that is distinct from that in ESCs.
Melatonin, an endogenous neurohormone secreted by the pineal gland, has a variety of physiological functions and neuroprotective effects. However, its protective role on the neural tube defects (NTDs) was not very clear. The aim of this study was to investigate the effects of melatonin on the incidence of NTDs (including anencephaly, encephalocele, and spina bifida) of offspring from diabetic pregnant mice as well as its underlying mechanisms. Pregnant mice were given 10 mg/kg melatonin by daily i.p. injection from embryonic day (E) 0.5 until being killed on E11.5. Here, we showed that melatonin decreased the NTDs (especially exencephaly) rate of embryos exposed to maternal diabetes. Melatonin stimulated proliferation of neural stem cells (NSCs) under hyperglycemic condition through the extracellular regulated protein kinases (ERK) pathway. Furthermore, as a direct free radical scavenger, melatonin decreased apoptosis of NSCs exposed to hyperglycemia. In the light of these findings, it suggests that melatonin supplementation may play an important role in the prevention of neural malformations in diabetic pregnancy.
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