“慎”在中国传统医业道德规范中的地位

“慎”在中国传统医业道德规范中的地位表现为以下几方面：传统医业道德规范以“慎”为核心;历代医家把“慎”的规范要求落实在行医施治的各个环节;而“慎”的规范观念体现出了传统医家生命至重的思想,在以生命为本方面实施了统一;同时,以“慎”为核心的传统医德还具有丰富的表现形式,如法、律、戒律、要等。     

The Physiological Role of Ferritin-Like Compounds in Bacteria

Iron, as the ferrous or ferric ion, is essential for the life processes of all eukaryotes and most prokaryotes; however, the element is toxic when in excess of that needed for cellular homeostasis. Ferrous ions can react with metabolically generated hydrogen peroxide to yield toxic hydroxyl radicals that in turn degrade lipids, DNA, and other cellular biomolecules. Mechanisms have evolved in living systems for iron detoxification and for the removal of excess ferrous ions from the cytosol. These detoxification mechanisms involve the oxidation of excess ferrous ions to the ferric state and storage of the ferric ions in ferritin-like proteins.

There are at least three types of ferritin-like proteins in bacteria: bacterial ferritin, bacterioferritin, and dodecameric ferritin. These bacterial proteins are related to the ferritins found in eukaryotes. The structure and physical characteristics of the ferritin-like compounds have been elucidated in several bacteria. Unfortunately, the physiological roles of the bacterial ferritin-like compounds have been less thoroughly studied. A few studies conducted with mutants indicated that ferritin-like compounds can protect bacterial cells from iron overload, serve as an iron source when iron is limited, protect the bacterial cells against oxidative stress and/or protect DNA against enzymatic or oxidative attack. There is very little information available concerning the roles that ferritin-like compounds might play in the survival of bacteria in food, water, soil, or eukaryotic host environments.     

Measuring sensitivity moment-by-moment: A microanalytic look at the transmission of attachment

Meta-analyses have indicated that the mediating power of sensitivity in the transmission of attachment across generations is not nearly as great as would be predicted by attachment theory (van IJzendoorn, 1995; De Wolff & van IJzendoorn, 1997). To make sense of these findings, the author suggests that current measures of sensitivity should be expanded to include the assessment of mother-infant behavior on a micro-behavioral level. This paper reviews evidence for two central propositions: (1) The internal working model of mothers is expressed in subtle, fine-grained interactive behaviors with their infants, and (2) infants perceive and remember these behaviors in the form of interactional expectancies. Following these propositions, hypothesized representational micromodels for each major attachment organization are then offered, based on the Parallel Distributed Processing (PDP) approach to information processing. In closing, this paper presents some of the most pressing unresolved issues for attachment researchers as they seek to empirically identify the mechanisms by which attachment is transmitted across generations.     

健康大鼠血管衰老性重塑与血管衰老相关基因的关系

目的通过研究健康大鼠血管衰老性重塑形态学变化及衰老相关基因表达,探讨血管衰老性重塑可能的分子调控机制,为临床有效干预血管衰老提供分子靶点。方法观察主动脉组织形态及内皮细胞显微结构变化,应用Western blotting分析4、10、16月和24月龄大鼠血管重塑p16INK4a和p21cip1蛋白表达变化。结果随增龄,大鼠主动脉管壁增厚,纤维化程度增高,内皮细胞形态呈现衰老改变,p16INK4a和p21cip1蛋白表达呈时间依赖性上调。结论血管衰老性重塑的分子机制之一可能与上调细胞周期蛋白p16INK4a和p21cip1的表达有关。进一步阐明其调控机制可为延缓血管衰老,防治动脉粥样硬化提供理论依据。     

Intracellular energetic units in healthy and diseased hearts

BACKGROUND:

The present review examines the role of intra-cellular compartmentation of energy metabolism in vivo.

OBJECTIVE:

To compare the kinetics of the activation of mitochondrial respiration in skinned cardiac fibres by exogenous and endogenous adenine nucleotides in dependence of the modulation of cellular structure and contraction.

METHODS:

Saponin-permeabilized cardiac fibres or cells were analyzed using oxygraphy and confocal microscopy.

RESULTS:

Mitochondria respiration in fibres or cells was upregulated by cumulative additions of ADP to the medium with an apparent K_m of 200 μM to 300 μM. When respiration was stimulated by endogenous ADP produced by intracellular ATPases, a near maximum respiration rate was achieved at an ADP concentration of less than 20 μM in the medium. A powerful ADP-consuming system, consisting of pyruvate kinase and phosphoenolpyruvate, that totally suppressed the activation of respiration by exogenous ADP, failed to abolish the stimulation of respiration by endogenous ADP, but did inhibit respiration after the cells were treated with trypsin. The addition of up to 4 μM of free Ca²⁺ to the actively respiring fibres resulted in reversible hypercontraction associated with a decreased apparent K_m for exogenous ADP. These changes were fully abolished in fibres after the removal of myosin by KCl treatment.

CONCLUSIONS:

Mitochondria and ATPases, together with cytoskeletal proteins that establish the structural links between mitochondria and sarcomeres, form complexes – intracellular energetic units (ICEUs) – in cardiac cells. Within the ICEUs, the mitochondria and ATPases interact via specialized energy transfer systems, such as the creatine kinase- and adenylate kinase-phosphotransfer networks, and direct ATP channelling. Disintegration of the structure and function of ICEUs results in dyscompartmentation of adenine nucleotides and may represent a basis for cardiac diseases.     

MicroRNA在微血管病变调控机制方面的研究进展

Microangiopathy is characterized by capillary basement membrane thickening and microthrombus formation. The process of microangiopathy involves multiple organs and tissues, and seriously endangers the patients’ health and quality of life during the later stage. Recent evidence shows that microRNAs play an important role in the regulatory mechanism of microangiopathy, including inflammatory response, oxidative stress, abnormalities of glucose and lipid metabolism, abnormal activation of the rennin-angiotensin system and so on. The regulatory mechanism has unique features of microangiopathy in different organs. At present, more and more attention has been paid to the roles of microRNAs in the pathogenesis of microangiopathy.