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1.
HER2-positive (HER2+) breast cancer (BC) is a heterogenous and multifaceted disease, with interesting therapeutic implications. First, all intrinsic molecular subtypes can be identified in HER2+ tumors, with the HER2-enriched being the most frequent. Such subtypes do not differ much from their counterparts in HER2-negative disease, apart for the high expression of genes in/near the HER2 amplicon on chromosome 17. Intrinsic subtyping, along with the quantification of ERBB2 mRNA levels, is associated with higher rates of pathologic complete response across neoadjuvant trials of dual HER2 blockade and might help select patients for de-escalation and escalation treatment strategies. Secondly, HER2+ tumors have a broad range of DNA alterations. ERBB2 mutations and alterations in the PI3K/Akt/mTOR pathway are among the most frequent and might predict benefit from potent pan-HER, PI3K and mTOR inhibitors. Moreover, HER2+ tumors are usually infiltrated by lymphocytes. These tumor infiltrating-lymphocytes (TILs) predict response to neoadjuvant anti-HER2-based treatment and exert a prognostic role. PD-L1, detected in ∼42 % of HER2+ BC, might also be useful to define patients responding to novel anti-PD1/PD-L1 immunotherapies. New multiparametric clinicopathologic and genomic tools accounting for this complexity, such as HER2DX, are under development to define more tailored treatment approaches. Finally, HER2-targeted antibody-drug conjugates (ADC) such as trastuzumab deruxtecan might be active in tumors with low expression of HER2. Overall, there is a need to molecularly characterize and develop novel targeted therapies for HER2+ disease.  相似文献   
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Abstract: We describe the use of restriction analysis on PCR-amplified DNA for detecting all B*27 subtypes except B*2710 and B*2711 (i.e. from B*2701 to B*2709). After detecting B*27 by Sty I, double digestions consisting of Sty I plus another informative enzyme led to subtype assignment. We used mismatched primers to create restriction sites when necessary. The method avoids group-specific amplifications and other laborious optimization procedures. It was successfully tested on a panel of well characterized cell lines covering different B*27 subtypes. Then, we studied a group of 57 ankylosing spondyiitis patients and 746 controls from the south of Spain. B*27 showed a very strong association with the disease (OR=211.27, P=\0˜7). B*2702 and B*2705 distribution in controls (20% and 77.1%, respectively) differed from previously reported data in the Spanish population. We unexpectedly found the B*2707 allele in our population (one control).  相似文献   
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Summary Forty-four Parkinson patients (19 patients of the rigid-akinetic type, 13, of the rigid-akinetic-tremor type, and 12, of the tremor type) were included in a study in order to analyse correlations of the expression of the motor symptoms tremor, rigidity, akinesia, with other clinical parameters, computertomographic aspect of brain atrophy and psychometrically assessed cognitive parameters. Rigidity and akinesia are significantly positively correlated with the severity of motor dysability, stage of the disease, and brain atrophy, as is akinesia with a history of pharmacotoxic psychosis. Tremor is significantly negatively correlated with motor dysability, stage of the disease, and history of pharmacotoxic psychosis. Akinesia is correlated with visuomotor dysfunction (tested with Bender Gestalt Test) and rigidity with the depression score (Zung scale). The tremor type is favorable, the rigid-akinetic type unfavorable with respect to motor disability and psychosis.  相似文献   
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目的:观察不同浓度的尼尔雌醇(NYL)和左炔诺孕酮(LNG)对人成骨肉瘤MG-63细胞株ERα和ERβ表达的作用,探讨旁分泌效应对ERα和ERβ基因表达的影响。方法:人成骨肉瘤MG-63细胞株分为(1)空白对照组:用含1% BSA无血清MEM培养液培养48 h;(2)阳性对照组:培养液中加入10-8 mol/L的17β-estradiol (E2) 培养48 h;(3)药物处理组:培养液中分别加入10-10,10-8,10-6 mol/L的NYL或LNG培养48 h;(4)药物处理+换液组:培养液中分别加入10-10 mol/L的NYL或10-8 mol/L LNG培养48 h,每12 h更换新的含有相应药物的培养液。用半定量RT-PCR检测各组细胞ERα和ERβmRNA的表达。结果:NYL及LNG均能诱导ERα和ERβ亚型mRNA表达上调,诱导ERαmRNA表达的最强作用浓度均为10-6 mol/L。NYL,LNG对ERβ mRNA表达最强作用浓度分别为10-10,10-8 mol/L。每12 h更换干预培养液对ERα表达无影响,但可抑制ERβ的表达。结论:NYL和LNG均可诱导MG-63细胞株ERα和ERβ mRNA表达上调,且2种亚型的表达存在相互制约关系;在NYL和LNG诱导ER亚型表达上调过程中ERβ的表达可能受到旁分泌作用的影响。  相似文献   
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目的:观察老年大鼠不同脑区胆碱能M1亚型受体的变化和黄芪对其的调节作用。方法:采用放射自显影技术显示大鼠脑M1受体,并用图像分析仪进行灰度分析,以反映M1受体在不同脑区的相对定量分布。结果:所得脑切片自显影灰度层次清晰,主要分布在大脑皮质、海马、纹状体部位,非特异结合灰度很低,老年大鼠皮质、海马、纹状体的灰度显著低于青年鼠,分别降低1578%,869%,1236%(P<005),老年服黄芪组三个部位的灰度均明显高于老年对照组,分别升高1663%,981%,1032%,(P<005)。结论:黄芪对老年大鼠降低的脑胆碱能M1亚型受体具有上调作用。  相似文献   
8.
目的 分析在新型冠状病毒肺炎流行背景下,2016年4月—2022年3月国内深圳市和济南市流感流行特点,了解我国南北方地区流感流行差异。 方法 使用深圳市和济南市国家级哨点医院2016—2022监测年度流感样病例(ILI)和流感病原学监测资料,分析流感流行特征和趋势。 结果 2016—2022监测年度深圳市和济南市国家级哨点医院的门急诊病例中流感样病例百分比(ILI%)分别为2.25%、3.45%。两地区ILI%最高的年份均为2021—2022监测年度。ILl年龄构成均以0~4岁为主(分别占40%、46%)。按月分析两地区流感病毒分离阳性率与ILI%变化的相关性,两者趋势均存在正相关(r=0.238,P<0.05;r=0.425,P<0.001)。两地区不同监测年度流感优势毒株型别均不相同,呈交替变化,但每年流行的型别及高峰期的优势毒株型别基本一致。 结论 2020—2021监测年度即新型冠状病毒肺炎流行初期,深圳市和济南市流感活跃程度明显低于往年平均水平且流行毒株型别单一,其余监测年度基本符合我国南、北方地区流感流行特征。  相似文献   
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This review examines the role of serotonin (5-HT) in depression. Dysfunction of serotonergic neurons has been implicated as one of the causes of endogenous depression. Since serotonergic neurons innervate the hypothalamus and these neurons send collaterals to several other brain areas, it is possible that hypothalamic sites which control hormone secretion receive the same serotonergic afferents that innervate other limbic areas in the brain. Several investigators have devised neuroendocrine challenge tests measuring the effect of 5-HT agonists on plasma cortisol and prolactin in depressed patients. These tests help to identify dysfunctional 5-HT neurons, and are a "window into the brain." The secretion of cortisol and prolactin is increased predominantly by 5-HT1 receptors. However, changes in 5-HT2 receptors have also been implicated in depression. Results from our laboratory and by others suggest that brain serotonergic neurons stimulate renin and vasopressin secretion by activation of 5-HT2 receptors. Therefore, the renin and vasopressin response to 5-HT agonists should be included in neuroendocrine tests of serotonergic function in affective disorders. Since antidepressants produce a decrease in the density of 5-HT2 receptors, renin and vasopressin could be used to evaluate the antidepressant potential of new drugs.  相似文献   
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本研究应用免疫细胞化学技术观察了雌性成年SD大鼠下丘脑内5-HT1A受体亚型(5-HT1AR)和5-HT2AR免疫阳性结构的分布。结果显示:5-HT1AR免疫阳性神经元在视前区大细胞核、视前室周核、视上核和下丘脑外侧前核等核团内密集分布。在内侧视前核、外侧视前区、下丘脑室周核、下丘脑外侧区、背内侧核、腹内侧核、结节核、结节乳头体核、乳头体内侧核和乳头体外侧核等结构内也有较多的分布;而在正中视前核、视交叉上核、下丘脑室旁核、下丘脑背侧核、弓状核、乳头体上核和乳头体前核等部位有散在的分布。与5-HT1AR不同,5-HT2AR免疫阳性反应产物主要见于纤维和终末,阳性胞体少且染色淡。5-HT2AR阳性胞体见于下丘脑室旁核、视上核、腹内侧核、结节核、视前内侧区、外侧区、外侧前核、下丘脑背内侧核等处。另外,在视前区前内侧视前核、视交叉上核背侧和外侧可见围绕血管分布、密集成团簇状、带有大小不同膨体的阳性神经纤维缠结。本文结果提示5-HT1AR阳性结构广泛地分布于大鼠下丘脑,而5-HT2AR在下丘脑分布较为局限。二者不同的分布特点,提示它们可能介导5-HT在下丘脑的不同生理功能。  相似文献   
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