7例肺腺癌转化小细胞癌患者的临床病理特征分析

目的:分析总结肺腺癌转化为小细胞癌的临床病理特征.方法:回顾性分析2014年1月至2018年12月7例于河北医科大学第四医院确诊为肺腺癌转化为小细胞肺癌(small cell lung cancer,SCLC)患者的临床、病理及随访资料.结果:随访截至2020年6月1日.肺腺癌发生小细胞癌转化的中位时间为31个月,转化前应用酪氨酸激酶抑制剂(tyrosine kinase inhibitors,TKI)的中位时间为14个月.3例患者的转化部位与原发部位相同.7例患者转化前神经元特异性烯醇化酶(neuron-specific enolase,NSE)水平均升高,病情进展部位多为多个部位,肺、骨、脑、胸膜及淋巴结常见.7例患者转化后的免疫组织化学指标显示TTF1均为阳性,而Napsin A均为阴性,Syn、CD56、AE1/AE3均为阳性,Ki67均为高表达,PD-L1均不表达转化后基因检测显示,6例患者仍保持原有EGFR基因突变类型.转化后治疗主要为以化疗为主的综合治疗,中位无进展生存期为6个月,5例患者死亡,中位生存时间为10个月.结论:肺腺癌一旦发生小细胞癌转化,疾病进展迅速,生存期短.肺腺癌EGFR E19突变及接受靶向治疗的患者发生小细胞癌转化的几率较大,首诊至转化的时间多>2年,转化前病情常呈多部位进展且NSE升高,转化后患者仍保持原有EGFR基因突变型.

Effect of propofol on local field potential in rat prefrontal cortex during working memory task

Propofol may produce memory impairment during anesthesia procedure. Local field potentials (LFPs) are used with increasing frequency in recent years to link neural activity to perception and cognition. In this study, effect of propofol on LFPs in rat’s prefrontal cortex during working memory task was evaluated. Young (approximately 3 month) male Sprague-Dawley rats were divided into two group: propofol rats and control rats. Propofol rats received propofol at 0.9 mg/Kg·min intravenously for 2 h. After 12 h, LFPs of all rats were measured simultaneously from multiple electrodes placed in prefrontal cortex while rats were performing a working memory task in Y-maze. LFPs instantaneous phase were obtained by applying Hilbert transform, and cross-correlation coherence of LFPs was calculated. The results indicate that propofol decreased the correct rate and crosscorrelation coherence of LFPs on the first two days (p 0.05). Our results suggest that propofol can impair cross-correlation coherence of LFPs in the first two days, but not long time.

LOW-DIMENSIONAL STRUCTURES:SP ARSE CODING FOR NEURONAL ACTIVITY

Neuronal ensemble activity codes working memory.In this work,we developed a neuronal ensemble sparse coding method,which can effectively reduce the dimension of the neuronal activity and express neural coding.Multichannel spike trains were recorded in rat prefrontal cortex during a work memory task in Y-maze.As discretesignals,spikes were transferred into cont inuous signals by estinating entropy.Then the normalized continuous signals were decomposed via non-negative sparse met hod.The non-negative components were extracted to reconstruct a low-dimensional ensemble,while none of the feature components were missed.The results showed that,for well-trained rats,neuronal ensemble activities in the prefrontal cortex changed dynamically during the.working memory task.And the neuronal ensemble is more explicit via using non-negative sparse coding.Our results indicate that the neuronal ensemblesparse coding method can effectively reduce the dimnension of neuronal activity and it is a useful tool to express neural coding.

Anticipatory activity in rat medial prefrontal cortex during a working memory task

Objective Working memory is a key cognitive function in which the prefrontal cortex plays a crucial role. This study aimed to show the firing patterns of a neuronal population in the prefrontal cortex of the rat in a working memory task and to explore how a neuronal ensemble encodes a working memory event. Methods Sprague-Dawley rats were trained in a Y-maze until they reached an 80% correct rate in a working memory task. Then a 16-channel microelectrode array was implanted in the prefrontal cortex. After recovery, neuronal population activity was recorded during the task, using the Cerebus data-acquisition system. Spatio-temporal trains of action potentials were obtained from the original neuronal population signals. Results During the Y-maze working memory task, some neurons showed significantly in- creased firing rates and evident neuronal ensemble activity. Moreover, the anticipatory activity was associated with the delayed alternate choice of the upcoming movement. In correct trials, the averaged pre-event firing rate （10.86 ± 1.82 spikes/ bin） was higher than the post-event rate （8.17 ± 1.15 spikes/bin） （P 〈0.05）. However, in incorrect trials, the rates did not differ. Conclusion The results indicate that the anticipatory activity of a neuronal ensemble in the prefrontal cortex may play a role in encoding working memory events.

Prognostic factors for patients with limited-stage small-cell lung cancer without receiving prophylactic cranial irradiation

Objective:This retrospective study aims to explore the risk factors for brain metastasis and the prognostic factors for overall survival(OS)in patients with limited-stage small-cell lung cancer(LS-SCLC)who have no brain metastases according to magnetic resonance imaging(MRI)and have not received prophylactic cranial irradiation(PCI)after first-line chemoradiotherapy.Methods:A total of 107 patients who were treated in the Fourth Hospital of Hebei Medical University from January 2013 to December 2017 were enrolled in this study.The patients were treated with etoposide/platinum chemotherapy and thoracic radiotherapy(TRT)with involved-field irradiation.The median dose of the radiotherapy was 60 Gy(50-64 Gy).The primary study endpoints include BMFS(brain-metastasis-free survival)and OS(overall survival).The Kaplan-Meier method was applied to estimate survival,with a log-rank test used to ascertain statistical significance.The multivariate Cox proportional hazards model was used to determine the prognostic factors for survival.Results:The median follow-up of all patients was 18.8 months(range:7.9–65.1 months)and the median follow-up of surviving patients was 26.7 months(range:18.8–65.1 months).The median OS of the whole cohort was 20.1 months,and the 1-,2-and 3-year OS rates were 84.9%,44.9%,and 25.9%,respectively.The 1-,2-,and 3-year BMFS rates were 69.0%,49.9%,and 40.7%,respectively.50 patients(46.7%)developed brain metastases during the follow-up period,and the median time from the start to brain metastasis was 10.7 months(range:4.8–31.1 months).As shown by multivariate analysis,independent prognostic factors of OS included cycles of chemotherapy(P=0.019),the response to initial treatment(P=0.011),and the start time of TRT(P=0.044).The independent prognostic factors of BMFS included the clinical stage(P=0.008),the response to initial treatment(P=0.024),and the start time of TRT(P=0.028).Conclusions:For patients with LS-SCLC who have not received PCI,favorable factors for lower brain metastasis and higher survival include early clinical stage,CR to initial chemoradiotherapy,early TRT,and adequate cycles of chemotherapy.PCI is still recommended as the standard modality since the incidence of brain metastases was high(46.7%).