Endoplasmic reticulum (a review of the literature)]

Recent data on the structural and molecular organisation of the endoplasmic reticulum (ER) are reviewed. A special attention is paid to the mechanism of soluble and integral membrane protein translocation across the ER bilayer. A model of phospholipid-coupled polypeptide translocation is introduced served to overcome hydrophobic and (or) conformational constraints during the passage of polar amino acid residues within a polar environment of the ER membrane. In addition the mechanisms of diverse covalent and noncovalent post-translocational polypeptide modifications are considered, together with the process of the sorting events among ER-resident polypeptides and those destined to leave the ER domain for the Golgi apparatus.     

Effect of cyclosporine on the lymphoid organs of CBA mice]

The influence of cyclosporine which is an immunodepressant on morphology of the lymphoid organs was studied on CBA mice. The immunodepressant was administered intramuscularly in a single LD50 and in a dose of 7 mg/kg for the treatment course of 21 days. The examinations were performed in various periods within 28 days after discontinuation of the drug use. It was shown that cyclosporine induced cell depletion in the thymus cortical and medullar zones, inhibition of lymphocyte mitotic activity, alteration of the Hassall corpuscles and impairment of their formation. It also induced devastation of the thymus-dependent zones in the mesenteric lymph nodes and spleen. When cyclosporine was used in the course doses the morphological changes in all the lymphoid organs were more marked. The morphological changes were reversible.     

Yeast superoxide dismutase: isolation and properties (review of the literature)]

Modern data are reviewed on isolation procedures and properties of superoxide dismutase from Saccharomyces cerevisiae. Properties of superoxide dismutase (SOD) from yeast and SOD from macro-organisms were compared.     

Ontogeny of primary lymphoid organs and lymphoid stem cells

Cells of the immune system go through a series of important developmental steps that begin early in embryonic life and include, first, the various waves of hemopoietic-cell production in the embryo and, second, the homing of these cells to the hemopoietic organs, which are the sites of hemopoiesis and lymphopoiesis in embryonic and adult life. The avian embryo is an important model for investigating these early steps; and this paper presents a comprehensive review of the work done on the early ontogeny of the avian immune system.     

Prion pathogenesis and secondary lymphoid organs (SLO)

Prion diseases are subacute neurodegenerative diseases that affect humans and a range of domestic and free-ranging animal species. These diseases are characterized by the accumulation of PrP^Sc, an abnormally folded isoform of the cellular prion protein (PrP^C), in affected tissues. The pathology during prion disease appears to occur almost exclusively within the central nervous system. The extensive neurodegeneration which occurs ultimately leads to the death of the host. An intriguing feature of the prion diseases, when compared with other protein-misfolding diseases, is their transmissibility. Following peripheral exposure, some prion diseases accumulate to high levels within lymphoid tissues. The replication of prions within lymphoid tissue has been shown to be important for the efficient spread of disease to the brain. This article describes recent progress in our understanding of the cellular mechanisms that influence the propagation of prions from peripheral sites of exposure (such as the lumen of the intestine) to the brain. A thorough understanding of these events will lead to the identification of important targets for therapeutic intervention, or alternatively, reveal additional processes that influence disease susceptibility to peripherally-acquired prion diseases.     

Effect of hypokinesia on nucleic acid and protein metabolism in the lymphoid organs of rats

Metabolism of nucleic acids and protein by lymphoid cells of the rat spleen and thymus was studied under conditions of 22-day hypokinesia. It was shown that in the course of hypokinesia the loss of cellular mass by the spleen and thymus was associated with varied biochemical changes in the remaining lymphoid cells. The thymocytes showed a significant activation of nucleic acid and protein biosynthesis. Meanwhile in spleen lymphocytes, DNA and RNA metabolism was inhibited with no appreciable changes in protein metabolism. Potential mechanisms of changes in metabolism of thymus and spleen lymphocytes under long-term hypokinesia are discussed.     

Endovascular embolization of arteriovenous lung fistulas (review of literature and own results)]

The authors analyze the literature data on and their own experience in endovascular closure of arteriovenous lung fistulas: 20 fistulas were closed in 12 patients, in whom transcutaneous catheterization of the pulmonary artery was performed. Large-frame angiopulmonography made it possible to reveal 10 common arteriovenous lung fistulas (7 single and 3 multiple ones). Afterwards the diagnostic procedure was turned into a therapeutic one. Several types of spirals, spongogel fragments, pieces of felt and pools with wool were used as embolizing materials. All these measures resulted in hermetic closure of the arteries and a complete stop of pathological right-left shunting of the blood at the lung level and positive dynamics of blood gaseous indices.     

Effect of the ionic environment and of various neurotransmitters on spontaneous motility in snail intestine (author's transl)]

A spontaneous rhythmic motility of the isolated intestine in snail, Chryptomphalus hortensis, has been registered at 30 degrees C with the aid of an electronic transductor and an appropriate amplification. These slow regular movements are affected by ionic composition changes in the suspension medium. Na+, K+ and Ca++ ions prove to be important in this motility, and the addition of Ba++ markedly stimulates it. ACh produces hypermotility from 1.8 X 10(-11) g/ml. Its effect decreases in the presence of atropine and increases in that of pyridostigmine. The intestine is sensitive to 5-HT from 10(-10) g/ml, which stimulates its activity. The effect of histamine is weak. Low concentrations of adrenaline tend to increase the amplitude, whereas concentrations from 10(-5) g/ml onward produce a cease of motility in relaxation.     

斜带石斑鱼淋巴器官个体发育的组织学

本文应用连续组织切片技术和组织学观察,对出膜后1～60天的斜带石斑鱼(Epinephelus coioides)各期仔鱼、稚鱼和幼鱼的淋巴器官组织进行了研究,描述了淋巴器官的个体发育过程和组织学结构特征。研究表明：实验水温为22．0～27．8℃时,孵化后第10天出现头肾原基。头肾原基由未分化的造血干细胞组成。随着鱼体的生长,头肾原基的造血干细胞很快分化成不同类型的细胞;头肾主要由网状内皮系统支持下的淋巴造血组织构成。第11天出现脾脏原基。脾脏原基由造血细胞组成,淋巴化速度相对较慢。脾脏在整个发育过程中,红细胞和类红细胞占优势,没有红髓和白髓之分。第13天出现胸腺原基。胸腺发育速度较快,是明显的淋巴器官。胸腺主要由胸腺细胞(淋巴细胞)和上皮细胞组成,外区和内区没有明显的界限,但很容易区分。胸腺外被单层的上皮细胞层与咽腔相隔,保持浅表的位置,并且在整个发育过程中,胸腺与头肾是独立分开的。免疫器官原基出现顺序是头肾、脾脏和胸腺;而免疫器官淋巴化的顺序是胸腺,头肾和脾脏。和其它硬骨鱼类一样,斜带石斑鱼在早期发育阶段,淋巴器官的发育较迟,出现相对滞后的现象[动物学报49(6)：819～828,2003]。     

Myocardial ischemic preconditioning: pathophysiological mechanisms and prospects of clinical application (a literature review)]

Ischemic preconditioning (IPC, i.e. increase in the organ resistance to a prolonged ischemia which occurs after a brief ischemic challenge) seems to be one of the most powerful endogenous cardioprotective mechanisms known to date. Current data regarding molecular mechanisms of early (classic) IPC as well as the second window of protection are reviewed in the context of the concept of sequential three-staged development of protective effect. Based on original and published data, possible mechanisms of remote IPC are considered. The review comprises current ideas of existence of the IPC clinical correlates and its use in clinic.