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81.
Fecal microflora and lactate concentrations in blood and feces obtained from a patient (a 5 year-old boy) with short-bowel syndrome (SBS) were compared during acidosis to results for the normal condition (no SBS symptoms). The taxonomical position of the lactobacilli found predominantly in the feces sample obtained 2 days before the fifth attack was also studied. The D-lactate level in serum obtained 1 day after the fourth attack was 10-fold higher than that for the normal condition, although there was not a great difference in L-lactate levels. D-Lactate (3.91 mM) and L-lactate (2.86 mM) were also detected in the feces samples collected 2 days before the fifth attack, while no lactate was detected in the feces sample for the normal condition. The counts of total fecal bacteria, especially anaerobic bacteria such as members of the family Bacteroidaceae, were found to be low. The counts of lactobacilli and the total population of lactobacilli relative to total fecal bacteria in the feces 2 days before the fifth attack (40.4%) were extremely high. In this case, a majority of the lactobacilli were D-lactate producers as determined by homolactic fermentation. These lactobacilli were identified as Lactobacillus delbrueckii subsp. lactis. The percentages of bifidobacteria relative to total fecal bacteria in feces samples obtained both 2 days before the fifth attack (50.9%) and for normal condition (61.9%) were also high, although these bacteria were L-lactate producers. In the feces samples for the normal condition, the D-lactate producers decreased to less than 10(9) per g, while the counts of L- or DL-lactate producers were 100-fold higher than the numbers in feces samples obtained 2 days before the fifth attack. These results suggested that an increase in the level of D-lactate producers, such as L. delbrueckii subsp. lactis, in the colon may be associated with the clinical expression of metabolic acidosis.  相似文献   
82.
BACKGROUND: The aim of this study was to analyze cellular and cytokine interactions governing the development of synovial tissue outgrowth in patients with rheumatoid arthritis (RA). METHODS: A single-cell suspension of dissociated synovial tissues of RA patients was cultured for a long period to develop tissue outgrowth. The resulting tissue outgrowth was characterized by immunohistochemical staining and ELISA. RESULTS: The tissue outgrowth developed in vitro included various cell types, such as macrophage-like synovial cells, fibroblast-like synovial cells and lymphocytes. Even after prolonged cultivation, synovial cells devoid of infiltrating T lymphocytes did not form tissue outgrowth. The outgrowth contained CD3+ cells, LeuM3 (CD14)+ cells and HLA-DR+ cells. The T cells expressed lymphocyte function-associated antigen (LFA)-1 and CD2, and the synovial cells expressed intracellular adhesion molecule (ICAM)-1 and LFA-3, suggesting possible interactions via LFA-1/ICAM-1 and CD2/LFA-3. Production of T-cell derived IFN-gamma and IL-17 and synovial-cell-derived fibroblast growth factor (FGF)-1 and IL-15 was confirmed in the tissue outgrowth as well as in RA synovial tissue. These cell types stimulate each other by secreting cytokines, leading to the secretion of proinflammatory cytokines and matrix metalloproteinase (MMP)-1 by the tissue outgrowth and proliferation of both lymphocytes and synovial cells. CONCLUSION: This study emphasizes the importance of cellular interactions between T cells and synovial cells, via adhesion molecules and the secretion of cytokines with stimulatory activity towards other cell types, for the hyperactivity of RA synovial cells.  相似文献   
83.
Neurons in area TE of the monkey inferior temporal cortex respond selectively to images of particular objects or their characteristic visual features. The mechanism of generation of the stimulus selectivity, however, is largely unknown. This study addresses the role of inhibitory TE neurons in this process by examining their visual response properties and interactions with adjacent target neurons. We applied cross-correlation analysis to spike trains simultaneously recorded from pairs of adjacent neurons in anesthetized macaques. Neurons whose activity preceded a decrease in activity from their partner were presumed to be inhibitory neurons. Excitatory neurons were also identified as the source neuron of excitatory linkage as evidenced by a sharp peak displaced from the 0-ms bin in cross-correlograms. Most inhibitory neurons responded to a variety of visual stimuli in our stimulus set, which consisted of several dozen geometrical figures and photographs of objects, with a clear stimulus preference. On average, 10% of the stimuli increased firing rates of the inhibitory neurons. Both excitatory and inhibitory neurons exhibited a similar degree of stimulus selectivity. Although inhibitory neurons occasionally shared the most preferred stimuli with their target neurons, overall stimulus preferences were less similar between adjacent neurons with inhibitory linkages than adjacent neurons with common inputs and/or excitatory linkages. These results suggest that inhibitory neurons in area TE are activated selectively and exert stimulus-specific inhibition on adjacent neurons, contributing to shaping of stimulus selectivity of TE neurons.  相似文献   
84.
85.
Porphyromonas gingivalis has been implicated as a causative pathogen in periodontitis. Immunotherapeutic approaches have recently been suggested to aid in the clearance of P. gingivalis from disease sites. Because antibody-Fc receptor (FcR) interactions play a role in the effector functions of polymorphonuclear neutrophils (PMN), we evaluated which FcR on PMN from gingival crevicular fluid (GCF) serves as an optimal target molecule for FcR-directed immunotherapy. GCF PMN and peripheral blood (PB) PMN from adult periodontitis patients were analyzed for their immunoglobulin G (IgG) and IgA FcR (Fc gamma R and Fc alpha R, respectively) expression and function by studying IgG- and IgA-mediated elimination of P. gingivalis. GCF PMN exhibited higher Fc alpha RI and Fc gamma RI levels and lower Fc gamma RIIa and Fc gamma RIIIb levels than PB PMN. Functional studies revealed that GCF PMN exhibited less of a capacity to phagocytose and kill IgG1-opsonized P. gingivalis than PB PMN. IgA1-mediated phagocytosis and killing capacity was, however, comparable between GCF PMN and PB PMN. In summary, these in vitro results document that Fc alpha RI represents a candidate target for FcR-directed immunotherapy for the clearance of P. gingivalis.  相似文献   
86.
To determine the phage types (PT) of Salmonella enteritidis found in Thailand and to clarify the potential for human infection by S. enteritidis in broiler chicken meat, human and poultry isolates taken from Thailand between 1990 and 1997 were phage typed and analyzed by pulsed-field gel electrophoresis (PFGE). Ten different PT were found among the 302 isolates phage typed, with PT 4 being the most frequent in human (73.9%) and poultry (76.2%) isolates, followed by PT 1 (8.0%), 8 (3.6%), and 7a (2.2%) in human isolates and by PT 7a (4.9%), 1 (3.7%), and 12 (2.4%) in poultry isolates. Of the 53 isolates analyzed by PFGE, 45 showed an indistinguishable pattern (pattern A) by BlnI-digested PFGE and the other 8 isolates showed a very similar pattern that differed by only a few bands. These results indicate the spread of a genetically identical clone of S. enteritidis in humans and poultry in Thailand.  相似文献   
87.
A large tumor massively occupying the left pleural cavity had the Andings of both typical carcinoid and oncocytoma which were thought to be of bronchogenic origin. The ultrastructural observation of the tumor revealed a mixture of rod-shaped granules in addition to usual round neurosecretory ones. In the nuclei of dark cells of the oncocytoma, a latticed or hatched structure was detected. Besides two adenomas and hyperplastic foci of large acidophilic cells in the thyroid, a black adenoma and cortical adenoma in the adrenal gland, were detected. Moreover, there was an ectopic adrenal gland in the retroperitoneum. Briefly it was suggested that the bronchial carcinoid presented may be related to multiple endocrine adenomatosis.  相似文献   
88.
Fourteen cases of gastrointestinal endocrine tumors were examined im-munohistochemically for peptide YY, pancreatic polypeptide, glucagon, and somatostatin. Peptide YY cells were present in seven tumors, pancreatic polypeptide cells in eight tumors, glucagon cells in six tumors, and somatostatin cells in nine tumors. All 7 rectal endocrine tumors examined were found to contain peptide YY, while in the tumors of the other sites peptide YY cells were not detected. Peptide YY cell population in the rectal tumors was small to moderate in comparison with pancreatic polypeptide and glucagon cell population. This study suggests that peptide YY cells may be a common constituent of rectal endocrine tumors together with pancreatic polypeptide and glucagon cells, and that the peptide YY spectrum of gastrointestinal endocrine tumors may be closely related to the location of the tumors. Moreover, it can also be said that peptide YY may be used as one of the markers of rectal endocrine tumors.  相似文献   
89.
1. Intracellular recordings were made from bipolar and amacrine cells in the isolated goldfish retina. Cells were identified mainly from their response patterns to a spot and an annulus in reference to the knowledge obtained from the previous work of intracellular Procion Yellow injection. Using white light and monochromatic lights receptive field organization of recorded cells were analysed.2. All bipolar cells had a centre-surround organization in their receptive fields. The field centre was estimated to be 100-200 mum in diameter, and the surround 1-1.5 mm.3. Bipolar cells were classified into two types according to the response properties to monochromatic lights. Opponent colour cells received inputs from red and green cones, responding with red on-centre, red and green off-surround or vice versa. Cells without colour coding received input from red cones both in the field centre and the surround. In these cells the centre and the surround were well balanced.4. Amacrine cells were also classified into two types, a sustained type and a transient type. The sustained type amacrine cells responded with a steady potential change and were colour coded. They were hyperpolarized by red and depolarized by green light. The transient type amacrine cells responded with transient depolarization at on and off of light flashes. They received input chiefly from red cones and were not colour coded. Both types of amacrine cells showed a large spatial summation in an area over 2.5 mm; centre-surround antagonism was not seen.5. Comparing the size of the receptive field with anatomy, especially with the size of dendritic spread, the field centre of bipolar cells agreed in size with their dendritic spread. Bipolar cell surround clearly exceeded its dendritic field. Since the response properties of the bipolar cell surround was mimicked most closely by the receptive field of external horizontal cells, the input to the bipolar cell surround is thought to be mediated by external horizontal cells.6. By comparing receptive field properties of various retinal cells it is suggested that both the opponent colour bipolar cells and the colour coded amacrine cells converge on to the double opponent ganglion cells.  相似文献   
90.
The morphology of the equine allantochorion at the tip of the pregnant horn was studied in the membranes of 14 mares. The findings in the allantochorion at the tip of the pregnant horn were of two types; one was growth retardation (hypoplastic villi, tunica adventitia of the vessels resembling embryonal connective tissue and the extended spaces of remnants of the extraembryonic coelom), the other was placental hypoxia or ischaemia (parakeratosis, stratified squamous metaplasia, necrosis of the trophoblasts, thickening of the basement membrane and fibrous hyperplasia of villous stroma). It seems likely that hypoplastic villi are caused by disordered formation of the microcotyledon accompanying the progression of pregnancy.  相似文献   
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