MR 弥散加权成像对鉴别诊断良恶性椎体压缩性骨折的临床价值研究

目的：探讨MR弥散加权成像(DWI)鉴别诊断良恶性椎体压缩性骨折的临床价值。方法：对57 例经临床或病理证实的椎体 良恶性压缩性骨折患者行矢状位T1WI、T2WI、T2WI/FS 及DWI扫描,研究其在常规序列和DWI序列上的表现,将常规MR 序列 和DWI序列检出率进行比较,测量正常椎体及病变椎体的表观弥散系数(ADC)值,并进行统计学分析。结果：(1)MR 常规序列和 DWI序列(b=500s/mm2)表现：良性椎体压缩性骨折呈长T1 长或等T2 改变,T2WI/FS 呈高信号,DWI 可以呈高信号、等信号及低 信号;恶性椎体压缩性骨折呈长T1 长T2 信号,大部分病灶T2WI/FS 及DWI呈高信号,少数变现为低信号;(2)MR 常规序列和 DWI 序列(b=500s/mm2)病灶检出率的比较：T1WI、T2WI/FS 及DWI序列病灶检出率均高于T2WI 序列,其间的差别有显著性意 义(P<0.01),T1WI、T2WI/FS 及DWI序列病灶检出率之间无显著性差异(P>0.01);(3)ADC 值比较：在DWI(b=500 s/mm2)上,良性组 ADC 值为(2.03± 0.83)× 10-3mm2/s,恶性组ADC 值为(1.37 ± 0.75)× 10-3mm2/s,正常组ADC值为(0.36± 0.21)× 10-3mm2/s,成像条 件相同时,良性组高于恶性组,两组间有明显的统计学意义(P<0.05)。结论：DWI可较好的反映椎体的弥散特征,ADC值作为量化 指标可对良恶性椎体压缩性骨折进行可靠鉴别。     

高血压脑出血患者术后重症监护治疗与早期再出血的相关因素分析

目的:探究高血压脑出血患者术后重症监护治疗与早期(24 h内)再出血的相关因素。方法:回顾性分析2014年1月至2018年10月于中山大学附属第一医院及中山市人民医院行手术治疗并进行重症监护的高血压脑出血患者的相关资料,记录术后早期发生再出血情况,比较其相关因素,包括年龄、性别、术前格拉斯哥昏迷量表(GCS)评分、出血量、术前收缩压、术后收缩压、镇静时间、插管时间、有无使用止血药、血压波动、血压差、有无镇痛情况,分析术后早期再出血的影响因素。结果:本研究共纳入465例患者,其中术后早期再出血患者44例,未再出血患者421例,再出血发生率为9.46%(44/465)。高血压脑出血术后早期再出血患者的术后收缩压、有无镇痛、血压差、血压波动与未再出血患者比较差异具有统计学意义(P0.05)。术后早期再出血患者的年龄、性别及术前GCS评分、出血量、术前收缩压、镇静时间、插管时间、有无使用止血药与未再出血患者比较差异无统计学意义(P0.05)。多因素Logistic回归分析显示,患者血压波动大是术后早期再出血的危险因素,手术前后血压差大、术后使用镇痛治疗是其保护因素。结论:高血压脑出血患者术后血压波动、手术前后血压差及术后镇痛治疗均是早期再出血的影响因素,合理降压及镇痛治疗可减少脑出血术后早期再出血的发生。     

Variation in male reproductive traits among three bitterling fishes (Acheilognathinae: Cyprinidae) in relation to the mating system

Male traits that correlate with fertilization success include testis size and structure, ejaculate size, ejaculation frequency, and sperm motility. Two hypotheses potentially explain interspecific differences in these traits: sperm competition and sperm limitation. We examined variation in six traits associated with fertilization success in three closely‐related species of bitterling fish; the European bitterling (Rhodeus amarus), the Chinese rose bitterling (Rhodeus ocellatus), and the Chinese bitterling (Rhodeus sinensis). Interspecific differences indicated that the three study species have evolved different sperm allocation strategies. Rhodeus amarus displayed the most developed reproductive apparatus with a number of traits associated with both high levels of sperm production and fertilization efficiency. Rhodeus ocellatus and R. sinensis appear to have more comparable sperm allocation strategies, although relative testis size and spermatozoa head : tail ratio were greater in R. sinensis, suggesting that sperm competition risk may be higher in this species. All three species possessed an unusually well developed sperm duct with evidence of mucin production, which greatly extends the longevity of sperm and, consequently, the period over which fertilization can occur. We discuss these findings in the context of differences in the mating systems of the species examined, and relate the results obtained to differences in the temporal and spatial clustering of fertilizations. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 622–632.     

应用Maxent生态位模型预测淡水钩虾(甲壳纲,端足目)的分布(英文)

预测物种的适生区对于物种资源的评估、保护以及生物多样性的管理非常重要。由于全球气候变化和人类的过度开发,冷水性无脊椎动物的衰减速度比在陆地和海洋生活的无脊椎动物都要高。目前关于中国淡水钩虾分布方面的研究很少,本研究基于103个地表淡水钩虾的不同分布位点和广布种湖泊钩虾Gammarus lacustris 23个不同分布位点以及32个环境因子数据,使用生态位模型(Maxent)预测了淡水钩虾和湖泊钩虾在我国的适生分布区域。结果显示淡水钩虾非常适合分布在我国的一些偏远山区,如长白山、太行山、横断山、天山、昆仑山和祁连山,而青藏高原的东部、西部边缘地区和南部分布地区、尼泊尔、不丹和朝鲜半岛也是淡水钩虾的潜在适生区域,但淡水钩虾在我国华南、华中和华北的平原地区分布却很少,其在我国的潜在分布区与-10℃和5℃1月平均气温线间的区域相似。淡水钩虾是典型的狭温性物种,在不适宜温度条件下很难存活,这可能也是限制其扩散和存活的关键性因素。     

Positioning of APOBEC3G/F Mutational Hotspots in the Human Immunodeficiency Virus Genome Favors Reduced Recognition by CD8+ T Cells

Due to constitutive expression in cells targeted by human immunodeficiency virus (HIV), and immediate mode of viral restriction upon HIV entry into the host cell, APOBEC3G (A3G) and APOBEC3F (A3F) have been considered primarily as agents of innate immunity. Recent bioinformatic and mouse model studies hint at the possibility that mutation of the HIV genome by these enzymes may also affect adaptive immunity but whether this occurs in HIV-infected individuals has not been examined. We evaluated whether APOBEC-mediated mutations within common HIV CD8⁺ T cell epitopes can potentially enhance or diminish activation of HIV-specific CD8⁺ T cells from infected individuals. We compared ex vivo activation of CD8⁺ T lymphocytes from HIV-infected individuals by wild type HIV peptide epitopes and synthetic variants bearing simulated A3G/F-induced mutations by measuring interferon-γ (IFN-γ) production. We found that A3G/F-induced mutations consistently diminished HIV-specific CD8⁺ T cell responses against the common epitopes we tested. If this reflects a significant trend in vivo, then adaptation by HIV to enrich sequences that are favored for mutation by A3G/F (A3G/F hotspots) in portions of its genome that encode immunogenic CD8⁺ T cell epitopes would favor CTL escape. Indeed, we found the most frequently mutated A3G motif (CCC) is enriched up to 6-fold within viral genomic sequences encoding immunodominant CD8⁺ T cell epitopes in Gag, Pol and Nef. Within each gene, A3G/F hotspots are more abundant in sequences encoding epitopes that are commonly recognized due to their HLA restriction. Thus, in our system, mutations of the HIV genome, mimicking A3G/F activity, appeared to abrogate or severely reduce CTL recognition. We suggest that the physiological significance of this potential effect in facilitating CTL escape is echoed in the adaptation of the HIV genome to enrich A3G/F hotspots in sequences encoding CTL epitopes that are more immunogenic at the population level.     

Sinupret Activates CFTR and TMEM16A-Dependent Transepithelial Chloride Transport and Improves Indicators of Mucociliary Clearance

Introduction

We have previously demonstrated that Sinupret, an established treatment prescribed widely in Europe for respiratory ailments including rhinosinusitis, promotes transepithelial chloride (Cl⁻) secretion in vitro and in vivo. The present study was designed to evaluate other indicators of mucociliary clearance (MCC) including ciliary beat frequency (CBF) and airway surface liquid (ASL) depth, but also investigate the mechanisms that underlie activity of this bioflavonoid.

Methods

Primary murine nasal septal epithelial (MNSE) [wild type (WT) and transgenic CFTR^−/−], human sinonasal epithelial (HSNE), WT CFTR-expressing CFBE and TMEM16A-expressing HEK cultures were utilized for the present experiments. CBF and ASL depth measurements were performed. Mechanisms underlying transepithelial Cl⁻ transport were determined using pharmacologic manipulation in Ussing chambers, Fura-2 intracellular calcium [Ca²⁺]_i imaging, cAMP signaling, regulatory domain (R-D) phosphorylation of CFTR, and excised inside out and whole cell patch clamp analysis.

Results

Sinupret-mediated Cl⁻ secretion [ΔI_SC(µA/cm²)] was pronounced in WT MNSE (20.7+/−0.9 vs. 5.6+/−0.9(control), p<0.05), CFTR^−/− MNSE (10.1+/−1.0 vs. 0.9+/−0.3(control), p<0.05) and HSNE (20.7+/−0.3 vs. 6.4+/−0.9(control), p<0.05). The formulation activated Ca²⁺ signaling and TMEM16A channels, but also increased CFTR channel open probability (Po) without stimulating PKA-dependent pathways responsible for phosphorylation of the CFTR R-domain and resultant Cl⁻ secretion. Sinupret also enhanced CBF and ASL depth.

Conclusion

Sinupret stimulates CBF, promotes transepithelial Cl⁻ secretion, and increases ASL depth in a manner likely to enhance MCC. Our findings suggest that direct stimulation of CFTR, together with activation of Ca²⁺-dependent TMEM16A secretion account for the majority of anion transport attributable to Sinupret. These studies provide further rationale for using robust Cl⁻ secretagogue based therapies as an emerging treatment modality for common respiratory diseases of MCC including acute and chronic bronchitis and CRS.     

血管抑素的临床应用研究进展

血管抑素是第一个被发现的肿瘤源性血管生成抑制因子,能抑制血管内细胞的增殖和迁移,从而抑制肿瘤的生长。通过一些实验方法能够检测肿瘤患者体内的血管抑素水平。血管抑素在未来的肿瘤治疗、诊断、预后判断和新生血管疾病的治疗中有着广阔的应用前景。     

18F-FDG PET 和治疗量131I 全身扫描对分化型甲 状腺癌根治术后转移灶检测的临床价值评估

目的:探讨18F-FDG PET显像和131I-全身扫描(131I-WBS)SPECT显像对分化型甲状腺癌(DTC)术后转移灶的临床诊断价值。方法:对57例外科术后拟行131I治疗的DTC患者行18F-FDG PET全身显像和131I-WBS扫描,观察和记录在糖代谢和碘代谢中DTC转移灶的定位及数量变化,并同时测定甲状腺球蛋白(Tg),促甲状腺激素释放激素(TSH)等实验室检查项目。结果:57例DTC患者18F-FDG PET显像发现真阳性20例、假阳性3例、真阴性31例、假阴性3例,其灵敏度为87.0%,特异性为91.2%。而131I-WBS扫描发现真阳性13例、假阳性2例、真阴性34例、假阴性8例,其灵敏度为61.9%,特异性为94.4%。PET显像和131I-WBS扫描共检出阳性病灶73个,其中淋巴结32个,肺5个,纵隔6个,骨26个,其他部位4个。PET显像发现43个阳性病灶(58.9%),而131I-WBS检出30个(41.1%)。当Tg水平>10μg/L时,随着Tg在血清含量的增高,两种显像方法的对DTC转移灶的阳性检出率亦随之升高。结论:两种检查对DTC术后转移灶的监测和131I的治疗具有良好的互补性,18F-FDG PET显像在Tg阳性和131I-WBS阴性的患者的转移灶检出上更具有优势,有重要的临床指导意义。     

甲亢患者甲状腺激素水平与血脂代谢相关性分析及临床意义探讨

目的:探讨甲亢患者甲状腺激素水平与血脂代谢指标之间的关系。方法:对160例甲亢患者治疗前后的甲状腺激素(TH)水平、血脂水平进行对照分析。结果:甲亢治疗前后与健康对照组比较,游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)明显增高,促甲状腺激素(TSH)明显降低,差异有统计学意义(P<0.01);总胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白胆固醇(LDL-C)、载脂蛋白A(apoAΙ)、载脂蛋白B(apoB)均明显降低,且差异具有统计学意义(P<0.01);低密度脂蛋白胆固醇(HDL-C)无明显变化(P>0.05)。结论:甲状腺激素与脂类代谢密切相关,临床上在诊治甲亢患者时,应当加强血脂水平的监测,以便更好地指导临床诊治,为疾病的发生发展、判断预后提供有价值的实验室检测指标。