Rongements sélectifs des os par les porcs-épics et autres rongeurs : cas de la grotte Tianyuan, un site avec des restes humains fossiles récemment découvert près de Zhoukoudian (Choukoutien)

The Tianyuan cave near Zhoukoudian is among the most special localities in North China for its many porcupine gnawing marks on the bones, as is often the case acknowledged only in South China. But porcupines did not gnaw all the bones, that is gnawing is selective. Skulls, mandibles, tooth roots and long bones are frequently gnawed. The short bones are almost free from gnawing. The selection indicates that, for porcupines, bone gnawing is not only a necessity for attrition of incisors, but also a process of extracting nutrients from the marrow. Additionally, the porcupine gnawing marks can also be employed to determine the provenance of the fossils that were discovered by the local people before the systematic excavation. Those bearing porcupine tooth marks only appear in the upper assemblage. The other significance of the gnawing marks is to infer the habitant of the cave. The bones from the human fossil bearing layer have few tooth marks, which may represent a period of human occupation of the cave. In the upper assemblage, the gnawing marks appear frequently, it may indicate that porcupine and other rodents lived in the cave during this time span.     

甘肃徐家城旧石器遗址石制品拼合研究

徐家城遗址是甘肃省新发现的含丰富旧石器文化遗物的遗址,主要埋藏于水洛河二级阶地上覆的马兰黄土中,年代在距今4.3~2.3万年间。徐家城遗址的拼合分析显示,4B、4C层剥片与石器加工行为是石制品空间分布形成的主要原因,但可能存在遗址使用时古人类对石制品位置改变的行为;4A层石制品零散分布可能反映了此时遗址处于古人类活动的边缘地带。遗址剥片方法以硬锤锤击法为主,石核剥片序列主要以转向为主,古人类对石料进行单层或多层开发;同时部分石器破碎后古人类可能对其进行再利用。平面分布显示发掘区内可能存在两个相对集中的剥片区域,并且古人类在同一区域剥片和加工石器。然因遗址石制品原料性质、发掘面积等局限性,拼合分析的优势并未在此项研究中尽现。今后此类研究应结合其他研究方法,综合多方面信息解释遗址形成过程、石器技术及遗址空间利用方式。     

水洞沟遗址第2地点古人类“行为现代性”及演化意义

解剖学意义上的现代人及其行为的演化与扩散是古人类学和旧石器考古学关注的重大科学问题。本文对水洞沟第2地点生态、技术、经济社会组织和象征行为方面的行为特征进行分析,于不同的文化层揭示出了不同的创新行为,它们分别预示了不同的演化意义。距今4~2万年间中国北方连续发展的石片石器技术系统从人类行为角度支持中国古人类连续演化的假说,在此理论背景下,探求中国古人类的行为创新需要关注人类行为的演化历程,进而总结创新表现,而非将总结自欧非等地区的现代行为清单与中国的考古学材料简单比对,进而讨论行为的现代与否。现代人出现后中国古人类行为的特殊性和多样性,促使研究者更多地关注行为变异性及不同适应策略产生的原因,而非将一系列的特征总称为现代行为;同时提醒学者们不应以总结自旧大陆西部的现代行为清单衡量和定性中国乃至东亚旧石器时代晚期人群的生物学属性和社会行为能力。     

Identification of a DNA Methylome Profile of Esophageal Squamous Cell Carcinoma and Potential Plasma Epigenetic Biomarkers for Early Diagnosis

DNA methylation is a critical epigenetic mechanism involved in key cellular processes. Its deregulation has been linked to many human cancers including esophageal squamous cell carcinoma (ESCC). This study was designed to explore the whole methylation status of ESCC and to identify potential plasma biomarkers for early diagnosis. We used Infinium Methylation 450k array to analyze ESCC tissues (n = 4), paired normal surrounding tissues (n = 4) and normal mucosa from healthy individuals (n = 4), and combined these with gene expression data from the GEO database. One hundred and sixty eight genes had differentially methylated CpG sites in their promoter region and a gene expression pattern inverse to the direction of change in DNA methylation. These genes were involved in several cancer-related pathways. Three genes were validated in additional 42 ESCC tissues and paired normal surrounding tissues. The methylation frequency of EPB41L3, GPX3, and COL14A1 were higher in tumor tissues than in normal surrounding tissues (P<0.017). The higher methylation frequency of EPB41l3 was correlated with large tumor size (P = 0.044) and advanced pT tumor stage (P = 0.001). The higher methylation frequency of GPX3 and COL14A1 were correlated with advanced pN tumor stage (P = 0.001 and P<0.001). The methylation of EPB41L3, GPX3, and COL14A1 genes were only found in ESCC patients'' plasma, but not in normal individuals upon testing 42 ESCC patients and 50 healthy individuals. Diagnostic sensitivity was increased when methylation of any of the 3 genes were counted (64.3% sensitivity and 100% specificity). These differentially methylated genes in plasma may be used as biomarkers for early diagnosis of ESCC.     

Synthesis and HPLC chiral recognition of regioselectively carbamoylated cellulose derivatives

Four regioselective-carbamoylated cellulose derivatives having two different substituents at 2-, 3-, and 6-position were prepared and evaluated as chiral stationary phases (CSPs) for high-performance liquid chromatography. Investigations showed that the nature and arrangement of the substituents significantly influenced the chiral recognition abilities of the heterosubstituted cellulose derivatives and each derivative exhibited characteristic enantioseparation. Some racemates were better resolved on these derivatives than the corresponding homogeneously substituted cellulose derivatives including a commercial CSP, Chiralcel OD. Racemic compounds shown in this study were most effectively discriminated on cellulose 2,3-(3-chloro-4-methylphenylcarbamate)-6-(3,5-dimethylphenylcarbamate) and 2,3-(3,5-dimethylphenylcarbamate)-6-(3-chloro-4-methylphenylcarbamate).     

Definition and risk factors of early recurrence based on affecting prognosis of esophageal squamous cell carcinoma patients after radical resection

Early recurrence after surgery could affect cancerous patients’ prognosis, but the definition of early recurrence and its risk factors for esophageal squamous cell carcinoma (ESCC) patients are still unclear. This study analyzed the clinical data of 468 post-surgery recurrent ESCC patients retrospectively. A minimum p-value approach was used to evaluate the optimal cut-off value of recurrence free survival (RFS) to define early recurrence. Risk factors of early recurrence were developed based on a Cox model. The optimal cut-off value of RFS to distinguish early recurrence was 21 months (p <0.001). Independent risk factors for early recurrence included tumor locations (HR=0.562, p <0.001), pathological T stage (HR=1.829, p <0.001), tumor diameter (HR=1.344, p = 0.039), positive lymph nodes (HR=1.361, p <0.001), and total resected lymph nodes (HR=1.271, p = 044). For the late recurrent patients, there was a much more significant survival advantage for recurrence after concurrent chemoradiotherapy than that after sequential chemoradiotherapy and radiotherapy alone (p = 0.0066). In conclusion, this study defined 21 months of RFS as early recurrence and also identified its risk factors. Concurrent chemoradiotherapy was suggested as preferred post-relapse treatment for late recurrent ESCC patients.     

地噻咪松诱导乳鼠胸腺细胞凋亡的研究

本文用透射电镜的方法,研究了地噻咪松诱导乳鼠胸腺细胞的凋亡,并确立了乳腺胸腺细胞中凋亡细胞学形态的特征;含溴化乙锭的琼脂多糖电泳检测乳鼠胸腺细胞中凋亡细胞的断裂ＤＮＡ;末端标记法直接,持异的标记乳鼠胸腺细胞中凋亡细胞断裂ＤＮＡ。     

Connective tissue growth factor and fibronectin secretion in renal tubular epithelial cells induced by TGF-beta1: suppressive effects of troglitazone

Although some studies have suggested that troglitazone could retard the progression of glomerulosclerosis, its effects on renal tubulointerstitial fibrosis have not been completely clarified. The aim of this study was to investigate the effects of troglitazone on the secretion of connective tissue growth factor (CTGF) and fibronectin (FN) in human renal proximal tubular epithelial (HK-2) cells induced by transforming growth factor-beta1 (TGF-beta1). The mRNA of CTGF and FN were measured by semi-quantitative RT-PCR. CTGF and FN protein were detected by Western blot and ELISA, respectively. Our results revealed that troglitazone could inhibit CTGF and FN expression in a dose-dependent manner in human renal proximal tubular epithelial cells induced by TGF-beta1, which may be one of the mechanisms of troglitazone contributing to retard the progression of renal tubulointerstitial fibrosis.