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1.
Transition to practice experiences for new primary care nurse practitioners (NPs) is of interest, particularly considering the lack of requirements and options for formal training programs. The purpose of this article is to describe new primary care NPs’ experience and perceived needs of transitioning to practice. New Nebraska NPs were surveyed. The main findings include increased confidence and perceived preparedness after 3 months of practice, as well as challenges and helpful supportive services for transitioning to practice. Additional information on the transition to practice experience was provided and supports developing a formal program.  相似文献   
2.
The study explored adult gerontology acute care nurse practitioner (AGACNP) student’s self-perception of confidence and competence in essential domains of nurse practitioner (NP) skills. A preclinical hospital immersion experience was developed to improve transition to the ACACNP role. AGACNP students participated in once-weekly sessions for 3 consecutive weeks, with 14 students completing the experience over a 3-year period. Data showed a 28.7% improvement in student’s self-perception of confidence and competence, with statistically significant improvement in clinical decision-making skills and NP role. AGACNP students requested additional days and appreciated direct faculty feedback, while faculty efficiently supported AGACNP role transition.  相似文献   
3.
目的:采用黄芪多糖(APS)与放射治疗(IR)联用,研究APS对人鼻咽癌CNE-1细胞的放疗敏感性及上皮间质转化(EMT)的作用机制。方法:采用细胞计数(CCK-8)法检测不同质量浓度APS(0,6.25,12.5,25,50,100,200 g·L-1)对CNE-1细胞的细胞毒性;克隆形成实验计算12.5 g·L-1APS与不同放射剂量(0,2,4,6 Gy)联用后对CNE-1细胞的存活分数(SF),利用线性二次方程数学模型(LQ)根据SF值绘制放射敏感曲线;细胞划痕和transwell小室实验分别检测各组细胞的迁移和侵袭能力;流式细胞仪检测各组细胞的凋亡情况;蛋白免疫印迹法(Western blot)检测各组细胞的EMT标记物、凋亡标记物以及蛋白激酶B/细胞外调节蛋白激酶(Akt/ERK)通路蛋白的表达水平。结果:克隆形成实验和放射敏感曲线结果表明,非毒性剂量12.5 g·L-1APS与4 Gy放射剂量联合给药可以明显增加CNE-1细胞的放疗敏感性;与空白组及IR组比较,APS与IR联用可以抑制CNE-1细胞的迁移和侵袭能力(P0.05),明显增加CNE-1细胞的凋亡率(P0.05)。与空白组及IR组比较,APS与IR联用可以显著下调间质型钙黏蛋白(N-cadherin),p-Akt和p-ERK蛋白表达水平,明显上调上皮型钙黏蛋白(E-cadherin),B淋巴细胞瘤-2相关X蛋白(Bax)和半胱天冬氨酸蛋白酶-3(Caspase-3)蛋白表达水平(P0.05)。结论:APS与IR联用可以抑制CNE-1细胞的迁移和侵袭,增加放疗引起的细胞凋亡,其可能通过抑制EMT和Akt/ERK通路有关。  相似文献   
4.
高迁移率族蛋白A2(HMGA2)是一种非组蛋白,本身不具有转录活性,但它可通过与染色质结合改变其结构,继而调节其他基因的转录,从而促进肿瘤的侵袭和转移。相关RNA基因能够调控HMGA2在肿瘤中的作用,同时肿瘤的侵袭性与上皮间质转化密切相关,可以通过靶向HMGA2基因治疗相关肿瘤。文章主要介绍HMGA2与肿瘤之间关系的研究进展。  相似文献   
5.
王博  魏芳 《现代肿瘤医学》2020,(16):2901-2904
E-钙黏蛋白(E-cadherin)是一种主要存在于人和动物上皮的黏附分子,主要功能是维持正常上皮细胞形态和结构完整性。现已在多种肿瘤研究中发现,E-cadherin表达的下调,极易造成肿瘤细胞向外周组织发生浸润和远端转移,但与E-cadherin相关研究在妇科恶性肿瘤中进展缓慢,E-cadherin在子宫内膜癌、卵巢癌和宫颈癌病变过程的调控机制尚不完全清楚,而且肿瘤的发生和发展是多因素作用的过程,需要进一步加强研究,该文章就 E-cadherin在妇科三大妇科恶性肿瘤中表达的意义及研究进展进行综述。  相似文献   
6.
Early stage localized prostate cancer (PCa) has an excellent prognosis; however, patient survival drops dramatically when PCa metastasizes. The molecular mechanisms underlying PCa metastasis are complex and remain unclear. Here, we examine the role of a new member of the fatty acid‐binding protein (FABP) family, FABP12, in PCa progression. FABP12 is preferentially amplified and/or overexpressed in metastatic compared to primary tumors from both PCa patients and xenograft animal models. We show that FABP12 concurrently triggers metastatic phenotypes (induced epithelial‐to‐mesenchymal transition (EMT) leading to increased cell motility and invasion) and lipid bioenergetics (increased fatty acid uptake and accumulation, increased ATP production from fatty acid β‐oxidation) in PCa cells, supporting increased reliance on fatty acids for energy production. Mechanistically, we show that FABP12 is a driver of PPARγ activation which, in turn, regulates FABP12''s role in lipid metabolism and PCa progression. Our results point to a novel role for a FABP‐PPAR pathway in promoting PCa metastasis through induction of EMT and lipid bioenergetics.

Abbreviations

AR
androgen receptor
ATP
adenosine triphosphate
CN
copy number
CPT1
carnitine palmitoyltransferase I
CS
citrate synthase
EMT
epithelial–mesenchymal transition
ET
electron transfer‐state
FABP
fatty acid‐binding protein
LD
lipid droplet
OA
oleic acid
PCa
prostate cancer
PPAR
peroxisome proliferator‐activated receptor
PPRE
peroxisome proliferator‐activated receptor response element
TZD
thiazolidinediones
  相似文献   
7.
8.
Protein phosphatase 4 regulatory subunit 1 (PP4R1) has been shown to play a role in the regulation of centrosome maturation, apoptosis, DNA repair, and tumor necrosis factor signaling. However, the function of PP4R1 in non-small-cell lung cancer remains unclear. In this study, we identify PP4R1 as an oncogene through Oncomine database mining and immunohistochemical staining, and we showed that PP4R1 is upregulated in lung cancer tissues as compared with that in normal lung tissues and correlated with a poor prognosis in lung cancer patients. Furthermore, in vitro study by wound-healing and Transwell assay showed that PP4R1 could promote migration and invasion of lung cancer cells. Mechanistic investigations revealed that PP4R1 could cooperate with high mobility group AT-hook 2 and thereby promotes epithelial-mesenchymal transition via MAPK/extracellular receptor kinase activation. Taken together, our study provides a rich resource for understanding PP4R1 in lung cancer and indicates that PP4R1 may serve as a potential biomarker in lung cancer therapies.  相似文献   
9.

Background

The conventional chemotherapy of colorectal cancer with irinotecan, 5-fluorouracil, and oxaliplatin remains one of the front-line treatments worldwide. However, its efficacy is quite low. Recently studies of the epithelial–mesenchymal transition (EMT) have become the focus of investigations into the cause of chemoresistance in several types of cancer, including colorectal cancer. The data about the role of EMT in chemosensitivity are controversial.

Materials and Methods

Human colon adenocarcinoma cell lines HT29 and HCT116 and 14 primary short-term cultures established from patient tumors were used. The chemosensitivity to irinotecan, 5-fluorouracil, and oxaliplatin was assessed using the (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. Immunocytochemistry, immunohistochemistry, and Western blot test were used to investigate the E-cadherin expression, the loss of which is a major hallmark of EMT.

Results

Elevated chemosensitivity of the cell line with EMT phenotype, HCT116, was demonstrated. Increased chemosensitivity was revealed in HT29 cell line upon EMT induction. E-cadherin–positive short-term cultures were more resistant to all the drugs tested, whereas each of E-cadherin–negative cultures showed sensitivity to at least one drug. The statistically significant dependency of cells viability on the E-cadherin expression (P < .04) was demonstrated on the short-term cultures using 2 concentrations of each drug.

Conclusion

The data obtained may serve as a basis for the analysis of colon cancer chemosensitivity using short-term cultures and the assay of E-cadherin expression.  相似文献   
10.
The transition from fetal to newborn life involves a complex series of physiological events that commences with lung aeration, which is thought to involve 3 mechanisms. Two mechanisms occur during labour, Na+ reabsorption and fetal postural changes, and one occurs after birth due to pressure gradients generated by inspiration. However, only one of these mechanisms, fetal postural changes, involves the loss of liquid from the respiratory system. Both other mechanisms involve liquid being reabsorbed from the airways into lung tissue. While this stimulates an increase in pulmonary blood flow (PBF), in large quantities this liquid can adversely affect postnatal respiratory function. The increase in PBF (i) facilitates the onset of pulmonary gas exchange and (ii) allows pulmonary venous return to take over the role of providing preload for the left ventricle, a role played by umbilical venous return during fetal life. Thus, aerating the lung and increasing PBF before umbilical cord clamping (known as physiological based cord clamping), can avoid the loss of preload and reduction in cardiac output that normally accompanies immediate cord clamping.  相似文献   
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