Patterns of RNA and Protein Synthesis in Post-Ischemic Livers

The re-establishment of the blood supply to a formerly ischemic liver lobe, before the “point of no return” of the tissue is reached, induces a series of changes in protein and RNA metabolism that are functional to the repair of the damage suffered by the cells. Among these events there is the increase, in synthesis of a group of proteins known as heat-shock (or stress) proteins, which are also induced in liver cells by different kinds of oxidative stress. The increase in synthesis of these proteins is largely due to the activation of their genes: some of these genes are also activated in cells stimulated to grow.

These observations suggest a link between oxidative stress, repair of cell damage and cell multiplication.     

The past,present and future of thermophilous Cyperus polystachyos Rottb. (Cyperaceae) on the island of Ischia (southern Italy)

Cyperus polystachyos is a hygrophilous, thermophilous and heliophilous plant with a punctiform distribution in southern Italy, where it is almost exclusively found on Ischia, an island in the Bay of Naples characterized by widespread volcanic hydrothermal activity. This species is a native of tropical and subtropical areas and there is evidence for ancient isolation events in the creation of its current distribution pattern. We have studied the historical literature available for this plant since 1800 and collected temporal and spatial presence data of this species in order to develop a habitat suitability map based on a GIS approach and using a multiple linear regression model. Moreover, we have used univariate and multivariate statistical analysis. The results show the importance of the environmental mosaic around fumaroles to preserve the species; urbanization and geothermal energy use of fumaroles in the past and the combination of abandonment of the typical agricultural system and the natural occurrence of reforestation in the present are the main causes of the decline in the number of populations.     

A survey of the genus Festuca L. (Poaceae) in Italy. Festuca gamisansii Kerguélen subsp. aethaliae,subsp. nova

ABSTRACT

Festuca gamisansii subsp. aethaliae, endemic to the Isle of Elba (Tuscan Archipelago) is described. The morphological, anatomical, karyological, ecological and chorological characteristics of the species are given. The main characteristics distinguishing F. gamisansii subsp. aethaliae from F. gamisansii subsp. gamisansii occurring in Corsica are also summarized.     

Abnormal exhaled ethane concentrations in scleroderma

Abstract

Scleroderma (systemic sclerosis) is a chronic multisystem autoimmune disease in which oxidative stress is suspected to play a role in the pathophysiology. Therefore, it was postulated that patients with scleroderma would have abnormally high breath ethane concentrations, which is a volatile product of free-radical-mediated lipid peroxidation, compared with a group of controls. There was a significant difference (p<0.05) between the mean exhaled ethane concentration of 5.27 pmol ml^–1 CO₂ (SEM=0.76) in the scleroderma patients (n=36) versus the mean exhaled concentration of 2.72 pmol ml^?1 CO₂ (SEM=0.71) in a group of healthy controls (n=21). Within the scleroderma group, those subjects taking a calcium channel blocker had lower ethane concentrations compared with patients who were not taking these drugs (p=0.05). There was a significant inverse association between lung diffusion capacity for carbon monoxide (per cent of predicted) and ethane concentration (b=?2.8, p=0.026, CI=?5.2 to ?0.35). These data support the presence of increased oxidative stress among patients with scleroderma that is detected by measuring breath ethane concentrations.     

肿瘤发生的细胞离子动态及其作为抗癌药标的综合效应

大量肿瘤细胞的有关研究表明,H+、Na+、Ca2+等细胞离子的动态对肿瘤发生起着关键作用.然而,单个离子作为代谢基础的作用是多方面的,其涉癌效果很不一致,有时还是相反的.因此,以控制单个离子动态作为抗癌药物的靶标,其效果并不理想.迄今对细胞离子的致癌作用的研究虽然是大量的,但均散见各章,缺少综合考虑.为此,本文简要介绍了上述离子的致癌作用,并探讨了以控制离子动态为药标,设计抗癌药物时应考虑的综合效应,供癌药物学研究者参考.     

植物叶绿体分裂的分子机制

叶绿体是植物细胞内一种重要的细胞器．它不仅是光合作用的场所,还是其它多种中间代谢的场所．叶绿体起源于蓝细菌,与其原核祖先类似,通过二分裂方式进行增殖．最近的研究表明,叶绿体的分裂装置包含原核起源和真核起源的蛋白质,它们在叶绿体的内膜内侧和外膜外侧协同作用以完成叶绿体的分裂．在过去十几年里,包括丝状温度敏感蛋白Z（FtsZ）、Min系统蛋白、质体分裂蛋白（PDV）和ARC蛋白等在内的多个叶绿体分裂相关组分被分离鉴定．本文简要介绍了叶绿体分裂装置各成员的发现、叶绿体被膜的收缩和叶绿体分裂位点的选择机制．另外,植物发育过程中叶绿体分裂可能受到细胞的控制,但目前对细胞如何调控叶绿体分裂知之甚少．本文对该领域的最新研究进展也进行了综述．     

Female Social Feedback Reveals Non-imitative Mechanisms of Vocal Learning in Zebra Finches

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Porphyromonas gingivalis promotes the motility of esophageal squamous cell carcinoma by activating NF-κB signaling pathway

Esophageal carcinoma, with a increasing incidence, is one of the most aggressive carcinomas in gastrointestinal tract. Epidemiologic studies demonstrate an association of oral pathogens with multiple diseases, including rheumatoid arthritis, cardiovascular diseases, diabetes, and gastrointestinal malignancies. Nevertheless, a causal relationship between oral pathogens and esophageal squamous cell carcinoma (ESCC) has not been elucidated. Here, we found that Porphyromonas was significantly enriched in the saliva of patients with ESCC, compared with that in normal human. In vitro studies showed that Porphyromonas gingivalis (P. gingivalis) promoted the proliferation and motility of ESCC cells, as evidenced by up regulated expression of key molecules implicated in NF-κB signaling pathway. These findings, for the first time, demonstrated a role of oral pathogens in inducing ESCC tumorigenesis and metastasis, which might involve regulation of NF-κB signaling pathway.