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191.
Breast cancers are heterogeneous and complex diseases, and subtypes of breast cancers may involve unique molecular mechanisms. The p16INK4a and p53 pathways are two of the major pathways involved in control of the cell cycle. They also play key roles in tumorigenesis. However, whether the roles of these pathways differ in the subtypes of breast cancer is unclear. Therefore, p16 and p53 expression were investigated in different breast cancer subtypes to ascertain their contributions to these cancers. A total of 400 cases of non-invasive ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC), including the major molecular subtypes luminal-A, luminal-B, Her-2, and triple-negative subtypes, and 50 cases of normal controls were compared. Luminal-A cancers expressed the lowest level of p16 among the subtypes in DCIS, and the level of p16 expression was up-regulated in the luminal-A of IDC (P<0.008). Triple-negative breast cancers were characterized by a correlation of p53 overexpression with a high level of p16 expression. Luminal lesion types with high p16 expression in DCIS were found to be more likely to develop into aggressive breast cancers, possibly promoted by p53 dysfunction. Taken together, the present study suggest that p16 expression in luminal-A breast cancers is associated with their progression from DCIS to IDC, and both p53 and p16 expressions are important for the development of triple-negative breast cancers in DCIS and IDC.  相似文献   
192.
Primulina elegans (Gesneriaceae), a new species from Vietnam is described. This species is similar to P. gemella and P. diffusa in having stolons and papillose-hispid leaves, but is easily distinguished from them by having 9–15 cymes and corollas with two brown stripes on the adaxial lip and nine purplish lines on the abaxial lip. Furthermore, Primulina elegans differs from P. gemmella by its broadly infundibuliform corollas with purplish glandular pubescent filaments, and from P. diffusa by having three slightly purplish glandular pubescent staminodes.  相似文献   
193.
Osteoclasts are multinucleated giant cells, responsible for bone resorption. Osteoclast differentiation and function requires a series of cytokines to remove the old bone, which coordinates with the induction of bone remodelling by osteoblast-mediated bone formation. Studies have demonstrated that AMP-activated protein kinase (AMPK) play a negative regulatory role in osteoclast differentiation and function. Research involving AMPK, a nutrient and energy sensor, has primarily focused on osteoclast differentiation and function; thus, its role in autophagy, inflammation and immunity remains poorly understood. Autophagy is a conservative homoeostatic mechanism of eukaryotic cells, and response to osteoclast differentiation and function; however, how it interacts with inflammation remains unclear. Additionally, based on the regulatory function of different AMPK subunits for osteoclast differentiation and function, its activation is regulated by upstream factors to perform bone metabolism. This review summarises the critical role of AMPK-mediated autophagy, inflammation and immunity by upstream and downstream signalling during receptor activator of nuclear factor kappa-B ligand-induced osteoclast differentiation and function. This pathway may provide therapeutic targets for bone-related diseases, as well as function as a biomarker for bone homoeostasis.  相似文献   
194.
Early stage diagnosis of Parkinson’s disease (PD) is challenging without significant motor symptoms. The identification of effective molecular biomarkers as a hematological indication of PD may help improve the diagnostic timelines and accuracy. In the present paper, we analyzed and compared the blood samples of PD and control (CTR) patients to identify the disease-related changes and determine the putative biomarkers for PD diagnosis. Based on the RNA sequencing analysis, differentially expressed genes (DEGs) were identified, and the co-expression network of DEGs was constructed using the weighted gene correlation network analysis (WGCNA). The analysis leads to the identification of 87 genes that were exclusively regulated in the PD group, whereas 66 genes were significantly increased and 21 genes were significantly decreased in contrast with the control group. The results indicate that the core lncRNA–mRNA co-expression network greatly changes the immune response in PD patients. Specifically, the results showed that Prader Willi Angelman Region RNA6 (PWAR6), LINC00861, AC83843.1, IRF family, IFIT family and calcium/calmodulin-dependent protein kinase IV (CaMK4) may play important roles in the immune system of PD. Based on the findings from the present study, future research aims at identifying novel therapeutic strategies for PD.  相似文献   
195.
Hou  Jinyan  Su  Pengfei  Wang  Dacheng  Chen  Xue  Zhao  Weiwei  Wu  Lifang 《Plant Cell, Tissue and Organ Culture》2020,142(1):143-156

Sapium sebiferum Roxb. is a widespread and economically important multipurpose tree due to its high value in ornamental, and biodiesel production as well as medicine. A highly efficient in vitro plant regeneration system through direct shoot organogenesis was established for the first time from leaves and petioles of S. sebiferum. The results showed that plant growth regulators (PGRs), mechanical damage, explant orientation, explant source, and developmental stage had a strong influence on the in vitro morphogenesis of S. sebiferum. For shoot organogenesis from leaves, the highest adventitious shoot induction rate (96.67%) with 25.67 shoots per explant was obtained when mechanically damaged leaves (the first three leaf explants at the top, leaf #1–3) were cultured with the abaxial surface placed down on Murashige and Skoog (MS) medium containing 0.5 mg L?1 thidiazuron (TDZ). For in vitro morphogenesis of petioles, the combination of 1-naphthylacetic acid (NAA) and 6-benzylainopurine (6-BA) played a key role in cell fate determination. All of the in vitro petioles produced adventitious shoots on MS medium containing 1.0 mg L?1 6-BA and 0.1 mg L?1 NAA, while they produced green calli on medium fortified with 0.5 mg L?1 6-BA and 1.0 mg L?1 NAA. The shoots were subcultured in medium fortified with 0.5 mg L?1 6-BA and 0.1 mg L?1 NAA for multiplication and elongation. The elongated shoots successfully rooted on half-strength MS (1/2 MS) medium fortified with 0.5 mg L?1 indole-butyric acid (IBA) and 0.25 mg L?1 indole-3-acetic acid (IAA), and the regenerated plantlets successfully acclimatized with a survival rate of 92.56% in the greenhouse. The genetic fidelity of in vitro regenerated plants was evaluated using inter simple sequence repeat molecular markers. The in vitro regenerated plants were found to be the true to their mother plant. This study will be beneficial for the large-scale propagation as well as the genetic improvement of S. sebiferum.

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196.
197.
Receptor tyrosine kinase-like orphan receptor 2 (ROR2) is a tyrosine-protein kinase receptor highly implicated in the growth plate and cartilage development, which may be involved in epithelial-mesenchymal transition (EMT) in breast cancer (BC) cells. Although ROR2 is known to promote the migration of BC cells, the detailed mechanism of this event is still not clear. Here, we found that ROR2 expression was significantly increased in BC lymphatic metastatic tissue as well as BC samples compared to normal adjacent breast tissues. A higher expression of ROR2 in MDA-MB-231 and a lower expression of ROR2 in MCF-7 cells were observed. MDA-MB-231-siROR2 cells with ROR2 knockdown inhibited MDA-MB-231 cell invasion, migration, and clonal formation, while MCF-7-OvROR2 cells with overexpression showed the opposite results. The underlying mechanisms involved in ROR2-induced EMT in MDA-MB-231 and MCF-7 cells were further investigated. ROR2 may activate EMT progression in BC cells by altering MAPK kinase 3/6 (MKK3/6) expression. The expressions of transforming growth factor-β, matrix metalloproteinase-2 (MMP-2), and MMP-9, which were related to tumor cell invasion activities, were notably increased in MCF-7-OvROR2 cells. The EMT markers, including snail, N-cadherin, tissue inhibitor of metalloproteinases-1, and vimentin, were significantly upregulated in MCF-7-OvROR2 cells. On the contrary, E-cadherin was obviously reduced expressed in MCF-7-OvROR2 cells. ROR2 may regulate the malignant phenotype of BC cells possibly via activation of mitogen-activated protein kinase (MAPK)/p38 signaling pathway. Collectively, ROR2 promotes BC carcinogenesis by mediating the MAPK/p38 pathway, which is independent of Wnt5α.  相似文献   
198.
Lv  Guoying  Li  Chuangang  Wang  Weiwei  Li  Ning  Wang  Kai 《Neurochemical research》2020,45(9):2082-2090
Neurochemical Research - Postoperative cognitive dysfunction (POCD) is a common complication induced by anesthesia or surgery, which affects the concentration, cognition and memory of patients....  相似文献   
199.
Liu  Zhenyang  Wang  Junyu  Tong  Haibo  Wang  Xiangyang  Zhang  Dong  Fan  Qin 《Neurochemical research》2020,45(7):1614-1625
Neurochemical Research - Glioma is a common invasive cancer with unfavorable prognosis in patients. Long non-coding RNAs (lncRNAs) exert significant functions in carcinogenesis of various cancers...  相似文献   
200.
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