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81.
Mice homozygous for klotho gene deletion are well established aging models as they mimic certain aspects of human senescence e.g. osteoporosis. Induced senescence may affect cellular functions and alter the histological properties of the extracellular matrices. The present study examined the histological and ultrastructural features of osteocytes and the surrounding bone matrix in klotho-deficient mice. As expected, osteoblasts showed a flattened shape with a weak immunoreactivity for alkaline phosphatase, and the bone matrix contained many empty osteocytic lacunae. The walls of both normal and empty lacunae were intensely immunopositive for osteopontin and dentin matrix protein-1, but featured an inconsistent immunoreactivity for osteocalcin and type I collagen. Not surprisingly, TUNEL-positivity, indicative of apoptosis, was found in many osteoblasts, osteocytes, and bone marrow cells of the klotho-deficient mice. In transmission electron microscopy, an amorphous matrix containing non-collagenous organic materials was recognizable around osteoblasts and in the osteocytic lacunae. Some osteoblasts on the bone surface featured these amorphous materials in vacuoles associated with their trans-Golgi network, indicating that, under klotho-deficient conditions, they synthesize and secrete the non-collagenous structures. Some osteocytes displayed pyknosis or degenerative traits. Thus, our findings provide histological evidence that klotho gene deletion influences the spatial distribution of osteocytes and the synthesis of bone matrix proteins in addition to the accelerated aging of bone cells.  相似文献   
82.
The polyhedrin gene inBombyx morinucleopolyhedrovirus (BmNPV) was replaced with the granulin gene ofTrichoplusia nigranulovirus (TnGV). The substitution was verified by Southern hybridization, and expression of granulin by the mutant virus, BmGran, was demonstrated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and by amino acid sequencing of the predominant protein of BmGran inclusion bodies (IBs). Light and electron microscopy examination of BmGran-infectedB. moriand BmN cells revealed large, cuboidal, polyhedron-like IBs in the nucleus and cytoplasm, but granules were not seen. IBs contained small, parallel, electron-dense streaks, which defined the geometric pattern of crystallization. Geometric patterns of nuclear IBs were frequently disrupted by occlusion of polyhedron envelope fragments, resulting in IB instability and fracturing. Virions were not embedded in most of the polyhedron-like IBs, but accumulated with polyhedron envelope fragments. Some virions were coated with matrix protein and were partially wrapped by polyhedron envelope. These results suggested that (1) the amino acid sequence of granulin is insufficient for determining IB morphology in TnGV-infected cells, and TnGV may have genes, not present in BmNPV, that control granule formation, and (2) interactions among the virion, the IB envelope, and the matrix protein may be important in virion occlusion and IB morphology and stability.  相似文献   
83.
Clinical application to ascertain the effects of aspoxicillin (ASPC), a new semisynthetic penicillin antibiotic, upon several infectious diseases of children was performed in 7 cases with pneumonia, 5 cases with acute bronchitis, each case with tonsillitis, enterocolitis, urinary tract infection and suspected sepsis. ASPC was injected by drip infusion and the dosage was 63-117 mg/kg/day in 3 and 4 times a day. Clinical efficacy obtained as "excellent" was in 7 cases, "good" in 8 cases "poor" in 1 case, and efficacy rate was 93.8%. From the bacteriological point of view, eliminated in each of H. influenzae, H. parainfluenzae, group A beta-Streptococcus and unchanged in a case of E. coli. There were transient thrombocytopenia in 2 cases and eosinophilia in 3 cases.  相似文献   
84.
Osteopenia/osteoporosis and sarcopenia are common geriatric diseases among older adults and harm activities of daily living (ADL) and quality of life (QOL). Osteosarcopenia is a unique syndrome that is a concomitant of both osteopenia/osteoporosis and sarcopenia. This review aimed to summarize the related factors and clinical outcomes of osteosarcopenia to facilitate understanding, evaluation, prevention, treatment, and further research on osteosarcopenia. We searched the literature to include meta-analyses, reviews, and clinical trials. The prevalence of osteosarcopenia among community-dwelling older adults is significantly higher in female (up to 64.3%) compared to male (8–11%). Osteosarcopenia is a risk factor for death, fractures, and falls based on longitudinal studies. However, the associations between osteosarcopenia and many other factors have been derived based on cross-sectional studies, so the causal relationship is not clear. Few studies of osteosarcopenia in hospitals have been conducted. Osteosarcopenia is a new concept and has not yet been fully researched its relationship to clinical outcomes. Longitudinal studies and high-quality interventional studies are warranted in the future.  相似文献   
85.
Reactive oxygen species in NMDA receptor-mediated glutamate neurotoxicity   总被引:1,自引:0,他引:1  
In search of endogenous protective substances that inhibit neurotoxic action of glutamate and nitric oxide (NO), we found that brain-derived neurotrophic factor (BDNF), acting on TrkB receptor tyrosine kinase, inhibited neurotoxicity induced by glutamate and NO donors in cultured cortical neurons. In co-cultures of the mesencephalon and striatum, projection of mesencephalic dopamine neurons to the striatum attenuated N-methyl-d-aspartate (NMDA)-induced cytotoxicity in dopamine neurons themselves. Growth factors such as neurotrophins, which the target cells in the striatum would synthesize and secrete, may offer the protection of dopamine neurons against glutamate neurotoxicity.  相似文献   
86.
Placement of stents for the tracheal or carinal stenosis have a meaning of maintaining the airway. Failure of the stenting causes death. In cases of severe airway stenosis and low pulmonary function, the pulmonary support method should be performed instead of intubation and mechanical ventilation. Generally, PCPS (percutaneous cardio-pulmonary support system) is used as a pulmonary support. This method was very useful to place stents for airway stenosis. We concluded that PCPS was useful in emergency cases, and in cases of severe fixed type airway stenosis and low pulmonary function it had be on stand-by.  相似文献   
87.
Vasogenic edema on MELAS: a serial study with diffusion-weighted MR imaging   总被引:10,自引:0,他引:10  
The authors performed a serial study of a patient with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like syndrome (MELAS) who presented with diffusion-weighted MRI (DWI). DWI demonstrated a higher apparent diffusion coefficient in the lesion than in the control region during the acute stage of stroke. Vasogenic edema is present in stroke-like episodes in MELAS.  相似文献   
88.
We examined cytosolic cytochrome c in gerbil hippocampal CA1 and CA3 regions after induction of 5-min ischemia by immunoblotting. In the CA1 region, cytochrome c was detected in the cytosolic fraction from 1 to 6 h after ischemia by Western blotting, while it was not detected in the CA3 region. Following intraventricular administration of cyclosporin A (CsA), detectable cytosolic cytochrome c was dramatically decreased, and about 80% of CA1 neurons survived after ischemia. The present studies demonstrate that cytochrome c is translocated from mitochondria to the cytosol in the early stage of delayed neuronal cell death, and suggest the involvement of the mitochondrial permeability transition.  相似文献   
89.
Activated microglial cells and peripheral macrophages are hardly distinguishable from the viewpoints of morphology and function. There are various immunological markers common to both microglial cells and peripheral macrophages. In the present study, however, we found that microglial cells have distinct characters in terms of adhesion and morphology. By using a "rheoscope," that is an apparatus to rheologically measure the strength of cell adhesion to substrates, rat microglial cells were found to attach to polystyrene dishes much more weakly than alveolar and peritoneal macrophages. Interferon-gamma (IFNgamma) strengthened the adhesion of alveolar and peritoneal macrophages, whereas it weakened that of microglial cells. Morphological changes of microglial cells induced by IFNgamma were also different from those of peripheral macrophages. Furthermore, alveolar and peritoneal macrophages produced NO in response to IFNgamma, while microglial cells did not. When cultured on astrocyte-derived extracellular matrix (AsECM) in serum-free medium, only microglial cells extended multiple ramified processes. Conversely, alveolar and peritoneal macrophages on AsECM shrunk their ruffling membrane and rounded up. These distinctions between microglial cells and macrophages may reflect differences in cell lineages as well as environments in which individual cells reside.  相似文献   
90.
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