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21.
目的:探讨重组干扰质粒pshRNA-COX-2对人肝癌细胞Hep3B裸鼠皮下移植瘤生长和肿瘤血管生成的抑制作用。方法:重组干扰质粒pshRNA-COX-2转染Hep3B细胞并筛选后,RT-PCR和Western blot检测COX-2mRNA和蛋白表达,RT-PCR检测VEGFmRNA表达。将被成功转染的Hep3B细胞种植于裸鼠皮下,测量肿瘤大小,4周后处死裸鼠,免疫组织化学法检测肿瘤组织中COX-2蛋白表达和肿瘤微血管密度(MVD)。结果:与未转染细胞相比,干扰组COX-2mRNA和蛋白表达抑制率分别为65.3%和52.8%(P<0.05),干扰组VEGFmRNA表达抑制率为56.5%(P<0.05)。干扰组瘤体大小明显小于阴性组和空白组(P<0.01)。干扰组COX-2得分和MVD均明显低于阴性组和空白组(P<0.01)。结论:pshRNA-COX-2通过抑制COX-2表达明显抑制人肝癌细胞Hep3B裸鼠皮下移植瘤生长和肿瘤血管生成。  相似文献   
22.
Recently, vaspin was identified as an adipokine with insulin-sensitizing effects, which is predominantly secreted from visceral adipose tissue in a rat model of type 2 diabetes. In this study, we examined whether vaspin mRNA expression is a marker of visceral obesity and correlates with anthropometric and metabolic parameters in paired samples of visceral and subcutaneous adipose tissue from 196 subjects with a wide range of obesity, body fat distribution, insulin sensitivity, and glucose tolerance. Vaspin mRNA expression was only detectable in 23% of the visceral and in 15% of the subcutaneous (SC) adipose tissue samples. Vaspin mRNA expression was not detectable in lean subjects (BMI<25) and was more frequently detected in patients with type 2 diabetes. No significant correlations were found between visceral vaspin gene expression and visceral fat area or SC vaspin expression. However, visceral vaspin expression significantly correlates with BMI, % body fat, and 2 h OGTT plasma glucose. Subcutaneous vaspin mRNA expression is significantly correlated with WHR, fasting plasma insulin concentration, and glucose infusion rate during steady state of an euglycemic-hyperinsulinemic clamp. Multivariate linear regression analysis revealed % body fat as strongest predictor of visceral vaspin and insulin sensitivity as strongest determinant of SC vaspin mRNA expression. In conclusion, our data indicate that induction of human vaspin mRNA expression in adipose tissue is regulated in a fat depot-specific manner and could be associated with parameters of obesity, insulin resistance, and glucose metabolism.  相似文献   
23.
Background3D freehand ultrasound enables the creation of volumetric data. The acquisition of morphological features, such as muscle volume, is influenced by the variations in force applied to the skin with the ultrasound probe. To minimise the deformations, a concave-shaped plastic mount combined with a custom-shaped gel pad was developed for the ultrasound head, named Portico. This study analyses to what extent the Portico reduces muscle deformation and corresponding errors in estimating muscle volume.MethodTwenty medial gastrocnemius (MG) muscles were assessed (10 from typically developing children; 10 from children with spastic cerebral palsy). Two repetitions were acquired in each of the following approaches: (1) with the lower leg submerged in a water tank as a non-deformed reference; (2) probe-on-skin (PoS) as the conventional approach and (3) the newly introduced Portico. PoS and Portico data were registered with respect to the ones corresponding in a water tank. An in-house software package (Py3DFreeHandUS) was used to process the data and MG volume was estimated using MeVisLab. The minimal detectable change (MDC) was calculated.ResultsWith respect to the PoS approach, the Portico reduced muscle deformation by 46%. For both the typically developing and spastic cerebral palsy cohorts, lower MDCs were found when using the Portico.DiscussionDespite the improvements, the Portico did not yield statistically more reliable MG volume estimations than the traditional PoS approach. Further improvement can be attained by optimising the fit between the gel pad and the curvature of the limb, using a larger choice of Portico geometries.  相似文献   
24.
The issue of the severity of psychiatric disorders has great clinical importance. For example, severity influences decisions about level of care, and affects decisions to seek government assistance due to psychiatric disability. Controversy exists as to the efficacy of antidepressants across the spectrum of depression severity, and whether patients with severe depression should be preferentially treated with medication rather than psychotherapy. Measures of severity are used to evaluate outcome in treatment studies and may be used as meaningful endpoints in clinical practice. But, what does it mean to say that someone has a severe illness? Does severity refer to the number of symptoms a patient is experiencing? To the intensity of the symptoms? To symptom frequency or persistence? To the impact of symptoms on functioning or on quality of life? To the likelihood of the illness resulting in permanent disability or death? Putting aside the issue of how severity should be operationalized, another consideration is whether severity should be conceptualized similarly for all illnesses or be disorder specific. In this paper, we examine how severity is characterized in research and contemporary psychiatric diagnostic systems, with a special focus on depression and personality disorders. Our review shows that the DSM‐5 has defined the severity of various disorders in different ways, and that researchers have adopted a myriad of ways of defining severity for both depression and personality disorders, although the severity of the former was predominantly defined according to scores on symptom rating scales, whereas the severity of the latter was often linked with impairments in functioning. Because the functional impact of symptom‐defined disorders depends on factors extrinsic to those disorders, such as self‐efficacy, resilience, coping ability, social support, cultural and social expectations, as well as the responsibilities related to one's primary role function and the availability of others to assume those responsibilities, we argue that the severity of such disorders should be defined independently from functional impairment.  相似文献   
25.
It has recently been shown that Interleukin-1 receptor, type 1, an essential regulator of inflammation and inate immunity, undergoes regulated intramembrane proteolysis (RIP). Although IL-1R1-mediated intracellular signalling has been well studied, very little is known about how RIP of IL-1R1 is modulated. In this study, by using wild-type TRAF6 and TRAF6 mutants that are defective in its ubiquitin ligase activity, we show for the first time that TRAF6 induces ubiquitination of IL-1R1. We further demonstrate that of all TRAF family members examined, TRAF6 preferentially ubiquitinates IL-1R1. Moreover, we show that TRAF6 ubiquitin ligase activity and ubiquitination of IL-1R1 are positively correlated with IL-1R1 ectodomain shedding and subsequent gamma-secretase cleavage. Our results indicate that TRAF6-mediated ubiquitination of IL-1R1 has a decisive role in IL-1R1 signalling and propose a molecular mechanism whereby TRAF6 promotes ubiquitination and RIP of IL-1R1 through its ubiquitin ligase activity.  相似文献   
26.
27.
A 53-year-old man underwent implantation of a totally subcutaneous ICD (S-ICD; Boston Scientific). He was positioned supine, with the left arm abducted, externally rotated (i.e. palm up) and strapped to the arm extender. The generator was placed in the left mid-axillary line along the 5th-6th intercostal spaces and the defibrillation coil was tunneled anterior to the sternum. Defibrillation threshold (DFT) testing with 65 Jcaused a forceful pectoralis twitch. The patient woke up with a painful anteriorly dislocated left shoulder. Glenohumeral dislocation due to DFT testing has not been previously reported. It is likely that this complication is specific to the S-ICD implantation, and is related to positioning with the arm abducted, externally rotated, and immobilized, and use of greater defibrillation energy with current pathway through the bulk of the pectoralis muscle.Precautions may include extending the arm palm down, strapping the arm loosely, and adduction of the arm for DFT testing.  相似文献   
28.
Lung immaturity is the major cause of morbidity and mortality in premature infants, especially those born <28 weeks gestation. Proper lung development from 23–28 weeks requires coordinated cell proliferation and differentiation. Infants born at this age are at high risk for respiratory distress syndrome (RDS), a lung disease characterized by insufficient surfactant production due to immaturity of the alveoli and its constituent cells in the lung. The ErbB4 receptor and its stimulation by neuregulin (NRG) plays a critical role in surfactant synthesis by alveolar type II epithelial cells. In this review, we first provide an introduction to normal human alveolar development, followed by a discussion of the neuregulin and ErbB4-mediated mechanisms regulating alveolar development and surfactant production.  相似文献   
29.
Apoptotic cell death generally characterized by a morphologically homogenous entity has been considered to be essentially non-immunogenic. However, apoptotic cancer cell death, also known as type 1 programmed cell death (PCD), was recently found to be immunogenic after treatment with several chemotherapeutic agents and oncolytic viruses through the emission of various danger-associated molecular patterns (DAMPs). Extensive studies have revealed that two different types of immunogenic cell death (ICD) inducers, recently classified by their distinct actions in endoplasmic reticulum (ER) stress, can reinitiate immune responses suppressed by the tumor microenvironment. Indeed, recent clinical studies have shown that several immunotherapeutic modalities including therapeutic cancer vaccines and oncolytic viruses, but not conventional chemotherapies, culminate in beneficial outcomes, probably because of their different mechanisms of ICD induction. Furthermore, interests in PCD of cancer cells have shifted from its classical form to novel forms involving autophagic cell death (ACD), programmed necrotic cell death (necroptosis), and pyroptosis, some of which entail immunogenicity after anticancer treatments. In this review, we provide a brief outline of the well-characterized DAMPs such as calreticulin (CRT) exposure, high-mobility group protein B1 (HMGB1), and adenosine triphosphate (ATP) release, which are induced by the morphologically distinct types of cell death. In the latter part, our review focuses on how emerging oncolytic viruses induce different forms of cell death and the combinations of oncolytic virotherapies with further immunomodulation by cyclophosphamide and other immunotherapeutic modalities foster dendritic cell (DC)-mediated induction of antitumor immunity. Accordingly, it is increasingly important to fully understand how and which ICD inducers cause multimodal ICD, which should aid the design of reasonably multifaceted anticancer modalities to maximize ICD-triggered antitumor immunity and eliminate residual or metastasized tumors while sparing autoimmune diseases.  相似文献   
30.
摘要 目的:探讨皮下免疫治疗联合应用沙美特罗替卡松粉吸入剂治疗中度支气管哮喘缓解期患儿的临床疗效及对Th1/Th2相关细胞因子表达水平的影响。方法:选取南方医科大学佛山市妇幼保健院2020年1月~2020年12月收治的中度支气管哮喘缓解期120例患儿,按随机分组原则分为观察组和对照组各60例。对照组予以沙美特罗替卡松粉吸入剂(舒利迭)治疗,早上及晚上各吸1次。观察组在对照组的基础上给予皮下免疫治疗,进行12个月疗程的治疗。对比两组患儿支气管哮喘发作次数以及临床控制率、肺功能变化。检测两组患儿血清Th1相关细胞因子[白细胞介素-2(IL-2)、γ干扰素(IFN-γ)]和Th2相关细胞因子[白细胞介素-4(IL-4)、白细胞介素-6(IL-6)]水平。结果:与治疗前相比,两组患儿治疗6月及治疗12个月后发作次数均显著降低(P<0.05),且观察组患儿哮喘发作的次数低于对照组(P<0.01);治疗12个月后,观察组患儿的临床控制率显示为90%,显著高于对照组的66.67%(P<0.05)。治疗6个月后、治疗12个月后,观察组患儿的第1 秒呼气流速(FEV1)占正常预计值百分比(FEV1%)及呼气峰流速(PEF)占正常预计值百分比(PEF%)均显著高于对照组(P<0.01);而与治疗6个月后相比,两组治疗12个月后上述2项指标均显著升高,且观察组明显高于对照组(P<0.01)。治疗12个月后,两组患儿血清IL-2、IFN-γ水平均显著升高,且观察组明显高于对照组(P<0.01);而两组血清IL-4、IL-6水平均显著下降,且观察组明显低于对照组(P<0.01)。结论:皮下免疫治疗联合沙美特罗替卡松粉(舒利迭)治疗中度支气管哮喘缓解期患儿的临床疗效确切,患儿支气管哮喘发作次数明显减少,肺功能改善明显,其作用机制可能与调节Th1/Th2相关细胞因子平衡有关。  相似文献   
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