The ultrastructural characteristics of the endocrine cells of the normal murine cecum and in experimental escherichiosis]

Ultrastructural investigations and a quantitative analysis of caecum endocrine cells were performed in the period from 15 minutes to 2 weeks after inoculation, using the model of experimental escherichiosis. The authors identified 5 types of endocrinocytes in the caecum of mice and showed the reaction of these cells: degranulation, extrusion of granules and their accumulation dependent on the time of the exposure.     

Ultrastructural changes in rectal mucosa cells in experimental Escherichia infection

Ultrastructural changes of rectum epitheliocytes and cells of lamina propria were studied at the period from 15 minutes to 2 days after inoculation using the model of experimental escherichiosis. The results obtained allow to determine the correlation of ultrastructural changes and the data of morphometric analysis. Ultrastructural peculiarities were determined of the rectum cells and the different cell populations were studied during infection's process.     

The morphofunctional characteristics of the cecum in experimental escherichiosis]

Using the model of experimental escherichiosis in mice by means of morphological, immunomorphological, morphometrical and electron microscopy methods, the authors give morphofunctional characteristics of caecum 15 minutes to 2 weeks after inoculation. The authors show the dynamics of infectious process, characterized by changes of microcirculation, increasing lymphoplasmocellular infiltration, dystrophic changes in cells of neuroplexes and degranulation of mast and endocrine cells. The data obtained show that pathological process in caecum during experimental escherichiosis has an immune character, that the above portion of the intestine is a part of endocrine system.     

模拟失重对大鼠肠道菌群影响的研究

目的：研究模拟失重条件下大鼠肠道菌群变化情况。方法：选择性培养基分别对肠球菌、肠杆菌、类杆菌、乳杆菌以及双歧杆菌进行定量测定,扫描电镜观察大鼠盲肠上皮细胞的组织变化。结果：过路菌群中肠杆菌和肠球菌数量增加显著;原籍菌群中双歧杆菌减少十分明显,乳杆菌的数量也有不同程度的减少,而类杆菌的数量有增加的趋势。SD大鼠盲肠出现了肿胀细胞,上皮细胞颈毛排列紊乱、稀疏。结论：模拟失重条件下大鼠肠道微生态出现平衡失调。     

施普瑞螺旋藻对尾吊模拟失重大鼠肠道微生态失调的调整作用研究

目的：研究模拟失重条件下,施普瑞螺旋藻对大鼠肠道微生态失调的调整作用。方法：将基础饲料中加入5%的螺旋藻作为处理组饲喂大鼠,用选择性培养基分别对肠球菌、肠杆菌、类杆菌、乳杆菌以及双歧杆菌定量测定,扫描电镜观察大鼠盲肠上皮细胞的组织变化,结果：螺旋藻处理组过路菌群中肠杆菌和肠球菌数量变化并不明显;原籍菌群中双歧杆菌较对照组显著增多,类杆菌和乳杆菌的数量差异没有显著性,模拟失重条件下SD大鼠盲肠上皮有肿胀细胞出现,并且肠道上皮绒毛排列紊乱、稀疏、而螺旋藻处理组中只发现有少量的肿胀细胞,上皮绒毛致密,排列较整齐。结论：旋普瑞螺旋藻具有纠正在模拟失重条件下大鼠肠道微生态平衡失调的作用。     

Some aspects of the gastrointestinal microflora of germfree mice associated with cultured microfloras

Attempts are described to 'normalize' germfree mice by association with 3, 21 and 71 different intestinal bacterial cultures isolated from mice with an SPF flora. Germfree mice associated naturally with an SPF flora served as controls. Vital bacterial counts were determined by aerobic and anaerobic culture. Stomach and small intestine contained fewer bacteria per gram than caecum and large intestine. Aerobic vital counts from caecum and large intestine were higher in the experimental groups than in control mice. The aerobic and anaerobic flora in stomach and small intestine comprised mainly Gram-positive non-fusiform shaped rods. In the caecum and colon Gram-positive cocci predominated in the aerobic culture while in the anaerobic culture fusiform-shaped rods were prominent. Scanning electron microscopy of oesophagus, ileum, caecum and faeces demonstrated colonization of the oesophageal epithelium only after association with 71 bacterial strains; the filamentous bacteria present in the ileum of SPF mice were not found in the experimental groups and caecum and faeces contained mainly fusiform-shaped bacteria. Non-bacterial matter decreased in the caecum and faeces with increase in the complexity of the flora.     

Ultrastructure of the epithelial cells of the duodenum at the early stages of experimental Escherichia infection

Ultrastructural changes of duodenal epitheliocytes were studied at the period from 15 minutes to 24 hours after inoculation using the model of experimental esherichiosis. The results obtained allow to determine the succession of ultrastructural changes and dynamics of adenylate cyclase activity of epithelial cells, involvement of endocrine cells in the pathological process. Combination of the certain morphological and cytochemical reactions and their dynamics allowed to make conclusions about typical ultrastructural changes in epitheliocytes at the early stages of experimental esherichiosis.     

Age-related ultrastructural characteristics of various cells in acute hypoxia

Ultrastructural peculiarities, concerning reaction of cells in various populations brain-sensorimotor cortex, mammillary nuclei, vascular plexus; myocardium; liver; jejunum) in mature (6-8 months) and old (24-30 months) male white Wistar rats have been studied at an experimental acute hypobaric hypoxic hypoxia. Both general changes, that are manifested in various degree in different cell groups and organo-specific ones are noted. The manifestation degree of the reactive changes is evidently connected with certain metabolic and functional peculiarities, as well as with the character of cell restoration. In the old animals hypoxic hypoxia produces more profound destructive processes in all cell populations studied. This is accompanied with a restriction in ability to adaptation.     

The in-vitro effect of the leukocytic cationic protein preparation Intercide on Escherichia coli]

Intercide is a cationic protein with the molecular weight of 11.0-11.5 kD from human leukocytes. The in vitro effect of its different concentrations (0.6 to 1.8 mg/ml) on populations of Escherichia coli M17 and K12 and 120 E.coli isolates from various sources such as water, feces of healthy humans and patients with extraintestinal escherichiosis was studied. The experiments with the bacterial suspensions and broth cultures demonstrated that Intercide had an antibacterial action on both the stationary and growing cells. However, some strains of E.coli were resistant to the lethal effect of Intercide. It was observed for the first time that in a concentration of 1.8 mg/ml Intercide was able to stimulate the biomass growth of some E.coli strains in broth culture. The factor analysis showed that the Intercide stimulating effect was more often evident with respect to extraintestinal escherichiosis pathogens with high anti-Intercide and antilysozyme activities.     

Ultrastructural and functional features of the reversibility of sclerotic liver changes in rats treated with exogenous organ specific RNA

Ultrastructural peculiarities of hepatocytes and Kupffer's cells in rats during the spontaneous reversibility of the experimental cirrhosis of the liver under the usual conditions and also under the influence of exogenous RNA, administered by different methods, were studied. The changes in cell ultrastructure proved to correlate with those of the quantitative indices of the protein synthesizing the liver function during the hepatic cirrhosis reversibility. A positive role of the RNA influence of short duration on the intracellular reparative hepatocytes regeneration, and a negative one in case of RNA influence of long duration was revealed. Participation in the resorption of collagen both of the parenchymal cells and of the stroma was shown.     

Morphological characteristics of endocrine cells of the intestine in experimental Escherichia infection]

Ultrastructural investigation and quantitative analysis of endocrine cells of intestine were studied at the period from 15 minutes to 24 hours after inoculation using the model of experimental esherichiosis. The results obtained allow to determine the succession of changes of different types of endocrine cells in dependence on localization and duration of influence.     

Ultrastructural changes in <Emphasis Type="Italic">Yarrowia lipolytica</Emphasis> cells under stress conditions

Ultrastructural organization of the aerobic yeast Yarrowia lipolytica was studied under conditions of oxidative, heat, and ethanol stresses. It was shown that the following uniform changes in cell ultrastructure did not depend on the type of stress: enlargement of mitochondria, enhanced number and enlargement of peroxisomes, and formation of lipid granules. Similar ultrastructural changes also occurred during the transition of cells to the stationary growth phase. It was shown for the first time that accumulation of polyphosphate granules occurred as a stress response in yeasts. Moreover, numerous globular structures of unknown nature appeared on the cell wall surface under oxidative or heat stress. Under ethanol stress, the cells developed clearly marked deep invaginations of the cytoplasmic membrane. (The same changes in the cytoplasmic membrane were observed in the cells grown on ethanol.) Variations of the cell envelope structure along with the formation of polyphosphate granules were not observed in the stationary growth phase. Ultrastructural changes in the cells under stress conditions are in agreement with the previous data on survival, respiratory activity, and variations of the antioxidant systems.     

Effect of acute exercise stress in cardiac hypertrophy: I. correlation of regional blood flow and qualitative ultrastructural changes.

Ultrastructural myocardial cell changes were determined in eight miniswine after the development of pressure-overload hypertrophy induced by supra-valvular aortic constriction. Four miniswine served as control animals. Regional myocardial blood flows were measured at rest and during exercise stress with radioactive microspheres after two days and one month of aortic constriction. Exercise stress, causing the heart rate to increase to 85 percent of its maximum, was imposed twice weekly for 7 minutes on four pressure-overloaded animals and the four control animals to elicit differences between the control and experimental groups that might not occur at rest. After one month of pressure overload the swine were killed and myocardial samples were processed for electron microscopy. Ultrastructural changes similar to those in hypertrophied hearts were present throughout the left ventricular walls of the pressure-overloaded animals. Other changes consistent with ischemic injury were present in the subendocardial regions of pressure-overloaded animals subjected to exercise stress. These changes included disorganization of myofibrils, disintegration and broadening of Z-bands, swelling and aggregation of mitochondria, electron-dense deposits in mitochondria, decreased cristal density and vacuolization of mitochondria, intracellular edema, margination and clumping of nuclear chromatin, and a decrease of glycogen granules. Regional ischemia in the subendocardium of these animals was confirmed by functional studies which showed decreased regional myocardial blood flow to the subendocardium during exercise and S-T segment elevation for the first 2-10 days after inducing pressure overload. The ischemia, as shown by flow studies, during exercise stress persisted in the compensatory stage of hypertrophy although S-T segments returned to normal. Thus, the combined effect of pressure overload and exercise stress can produce focal subendocardial ischemia in the compensated, hypertrophied heart.     

Ultrastructural changes in the axons of the central nervous system in experimental amyotrophic leukospongiosis

Ultrastructural changes, various by their character and the degree of expression, have been found in axons of the spinal cord of guinea-pigs with amyotrophic leukospongiosis (AL) (a slow infection of the CNS). The dependence of the degree of degenerative changes on the disease duration is shown. Absorption of cellular debris by oligodendrocytes and astrocytes is noted. It seems that microglia does not participate in phagocytosis. The conclusion has been made that experimental AL is a convenient model for studying the mechanisms of death of the central axons and analysis of the glia cell function under the conditions of keeping the blood-brain barrier intact.     

Adaptation of electrolytes and fluid transport in rat small and large intestine after distal small bowel resection

Na+, Cl- and water transport were studied in jejunum, caecum and colon after either 50% or 80% of small bowel resection (SBR). Four weeks after surgery, dry and wet weights, net absorption in vivo of sodium, chloride and water were determined. There was a significant intestinal growth after 50% or 80% SBR except for the colon which only showed increased tissue mass after 80% SBR. Net transport was stimulated both, per organ and per unit mass. In the small intestine and caecum both organ growth and changes in cell function appear to be involved in the adaptive response, regardless the extent of the small intestine resected. In the colon, compensatory growth appear to contribute to the adaptive response only after 80% SBR, whilst the transport function of the colonocytes seems to be stimulated after both types of SBR.     

The morphofunctional characteristics of the cecum in experimental influenza]

On the model of experimental influenza using morphological, immunomorphological, cytochemical, electron microscopy and morphometric methods, the authors provided morphofunctional characteristics of the caecum, showed the progression of infectious process and confirmed the dissemination of the virus, availability of virus particles in different cell populations, among them in lymphoid cells.     

The morphological characteristics of the cecum and its lymphoid tissue in BALB/C mice

The caecum has been studied at the light optic and electron microscopical levels. Amount of immune-competent cells and lymphoid nodules in the distal part of the mice caecum and in the human appendix vermiformis are essentially similar. It is possible to consider the distal (blindly closed) part of the caecum in the mice of the BALB/C line as a morphofunctional equivalent to the human appendix vermiformis and use it as an experimental model in studying diseases of the appendix.     

浙贝母鳞片细胞在寒冷条件下超微结构的变化

利用电镜手段观察了浙贝母鳞片细胞在寒冷条件下超微结构的变化。细胞中最明显的变化是出现了大量脂滴和淀粉粒壳的结构由清晰到模糊。一些高尔基体结构不清晰,内质网泡化。细胞中壁旁体较多,细胞核、细胞壁和胞间连丝正常。有时可见线粒体溢裂现象。以上现象表明为适应寒冷条件,细胞进行了内在代谢机制的调整。     

Effects of age and mannanoligosaccharides supplementation on production of volatile fatty acids in the caecum of rabbits

This trial studied the effect of including mannanoligosaccharides (MOS, Bio-Mos^®, Alltech Inc., USA) in the diet on the caecal volatile fatty acids (VFA) and pH of rabbits from 34 to 90 days of age. Three experimental diets were compared: control diet, zinc bacitracin (ZnBac) diet (control diet with 0.1 g ZnBac/kg feed) and MOS diet (control diet with 2.0 g MOS/kg feed). Rabbits were slaughtered at 34, 48, 69 and 90 days of age and caecal contents were collected and analyzed for dry matter, pH and VFA concentration. The empty caecum and caecal contents weights relative to live weight were also determined.Age affected (P<0.0001) VFA concentration and pH values in the caecum. The pH decreased with age whereas VFA concentration increased. Rabbits fed MOS had higher (P<0.05) VFA and tended (P=0.098) to had lower pH in the caecum than rabbits fed ZnBac and control diets. Acetic, propionic and butyric acids concentrations in the caecum increased with MOS but its molar proportions were similar among diets. Diet had no effect on empty caecum weight and caecal contents weight and dry matter concentration. There was no interaction effect between diet and age. From 34 to 90 days of age, VFA production was higher (P<0.05) in the caecum of rabbits fed MOS than in those fed ZnBac diet and control diet.The addition of MOS to the diet increased the VFA concentration in the caecum of growing rabbits from 34 to 90 days of age.     

Ultrastructure of nodose ganglia of the vagus nerve in burns

Ultrastructural changes of neurons of vagus nodal ganglia on section material of 30 dead persons in different periods of burn disease aged from 14 to 75 have been studied. Examination of the state of the nodal ganglia in different periods of burn disease showed ultrastructural changes in neurons, glial cells, blood capillary endotheliocytes, mitochondria, endoplasmatic net nuclei and cell membranes. The most marked destructive changes were seen in patients who died in late term of burn disease.