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121.
Two isoforms of nonmuscle myosin heavy chain IIB (MHC-IIB) are generated by alternative splicing; MHC-IIB(B2) differs from MHC-IIB(DeltaB2) by the insertion of B2 exon cassette near the actin binding region. Here we examined expressions of the two splice variants in developing and adult rat brains by in situ hybridization with isoform-specific oligonucleotide probes. In adult, MHC-IIB(DeltaB2) mRNA was highly expressed in neurons of the cerebral cortex, hippocampus, and cerebellum, whereas MHC-IIB(B2) mRNA was mainly distributed in the brainstem and cerebellum, with the highest level in Purkinje cells. During development, MHC-IIB(DeltaB2) mRNA was predominantly expressed in various regions of embryonic and neonatal brains, whereas MHC-IIB(B2) mRNA was low during embryonic stages. Up-regulation of MHC-IIB(B2) started in the cerebellum during early postnatal stages when dendritogenesis and synaptogenesis occur actively in Purkinje cells. We further employed immunofluorescence using two antibodies (one recognizing both splicing variants and another specific to MHC-IIB(B2)), and found similar and dense localization in cell bodies and dendrites of Purkinje cells. Therefore, splicing of the B2 exon cassette undergoes distinct temporal and spatial regulations in the brain in vivo, and the different exon usage seems unlikely to affect the somato-dendritic localization of MHC-IIB.  相似文献   
122.
123.
Hereditary coproporphyria (HCP) is an acute hepatic porphyriawith autosomal dominant inheritance, but with a variable degreeof clinical expression. Molecular cloning, sequencing and expressionof the defective gene for coproporphyrinogen oxidase (CPO) ina patient with HCP were carried out. Enzyme assays revealedthat CPO activity in EBV-transformed lymphoblastoid cells fromthe proband and one of her sisters was  相似文献   
124.
For evaluation of the degree of senescence in SAM-P, accelerated senescence prone mouse, formerly called SAM or prone series or P-series, consisting of SAM-P/1, SAM-P/2, SAM-P/3 and SAM-P/4 corresponding to P-1, P-2, P-3 and P-4 series, respectively, in the previous reports, and in SAM-R, accelerated senescence resistant mouse, formerly called resistant series or R-series, consisting of SAM-R/1, SAM-R/2 and SAM-R/3 corresponding to R-1, R-2 and R-3 series, respectively, in the previous reports, the grading score system was adopted. The items to be examined in this system include 11 categories selected from the clinical signs and gross lesions considered to be associated with the aging process. The degree of the senescence in each category was graded from 0 to 4 according to the detailed criteria devised in our laboratory. After 8 months of age each mouse was examined every 4 months, and some of the mice were examined after 2 months of age.In almost all categories, the grading score and incidence began to increase from 4 or 6 months of age and continued to increase with advancing age in both SAM-P and SAM-R. The increase, however, was more marked in SAM-P than in SAM-R. The slow but steady increase in the SAM-R levelled out at 24 months of age and was comparable to that of 12 months of age in SAM-P. In both SAM-P/1 at 8 months of age and SAM-R/2 at 12 months of age, there was a significant reverse correlation between total score of this grading score system and length of residual life after examination.Systematic and extensive studies using the grading score system showed that if the validity of the system is, based on “irreversibility” and “universality” of the changes in  相似文献   
125.
We investigated the increase of platelet-associated IgG and complement component 3 (C3) caused by the in vitro action of anti-platelet MoAbs, and the effect of mouse and human IgG on these events. Anti-glycoprotein IIb/IIIa and anti-glycoprotein Ib MoAbs caused a slight increase of C3, but not of platelet-associated IgG. In contrast, anti-CD9 and anti-Fcγ II receptor MoAbs caused an increase of both platelet-associated C3 and IgG. In particular, three MoAbs which activated the complement system caused a marked increase of C3. When platelet-rich plasma was treated with aspirin and prostaglandin E1 before incubation with antibodies, the increase of platelet-associated IgG was inhibited in all cases. In contrast, the increase of platelet-associated C3 was scarcely influenced. These results suggest that the binding to platelets of platelet-activating antibodies caused the increase expression of IgG molecules on the platelet surface and a possible increase of platelet-associated IgG. However, the increase of platelet-associated C3 appeared to depend on specific characteristics of the antibodies tested, such as a complement-activating effect. In addition, intact mouse or human IgG inhibited the increase of platelet-associated C3 caused by complement-activating antibodies, while F(ab')2 mouse or human IgG had no such effect. This suggested that the Fc portion of IgG may block the increase of C3 mediated by anti-platelet antibodies.  相似文献   
126.
Human saliva chromogranin A (CgA) is clinically promising as a psychological stress marker. However, expression of CgA is poorly understood in humans, although salivary gland localization of CgA in other mammals, such as rodents and horses, has been demonstrated. In the present study, we investigated the expression and localization of CgA in the human submandibular gland (HSG) using various methods. CgA was consistently localized in serous and ductal cells in HSG, as detected by immunohistochemistry and in situhybridization. Reactivity was stronger in serous cells than in ductal cells. In addition, strong immunoreactivity for CgA was observed in the saliva matrix of ductal cavities. Western blotting gave one significant immunoreactive band of 68 kDa in the adrenal gland, HSG and saliva. Finally, CgA was detected in secretory granules of serous and ductal cells by immunoelectron microscopy. In conclusion, CgA in humans is produced by HSG and secreted into saliva.  相似文献   
127.
Summary The immunofluorescent localization of glomerular basement membrane (GBM) antigens was examined in 52 specimens from normal kidneys and in various renal diseases using antisera to human GBM HGBM), IV type collagen (IV Col) and P3 antigen, a rat nephritogen. Anti-HGBM serum normally stained the GBM and the mesangium in a restrictive pattern, anti-IV Col serum stained the GBM and the mesangium in a wider pattern and anti-P3 serum stained only the GBM. In mesangial proliferative glomerulonephritis, including IgA nephropathy pathy and Henoch-Schönlein nephritis, the widened mesangial areas were stained with anti-HGBM and anti-IV Col sera. In membranous nephropathy, the punched-out lesions of thickened GBM were demonstrated with the three antisera in moderate cases and a double linear distribution with fine granulation with anti-HGBM and anti-IV Col sera were revealed in one severe case. In membranoproliferative glomerulonephritis, the expanded mesangium and thickened capillary walls were stained with anti-HGBM and anti-IV Col sera, while the outer line of glomerular capillary walls was only positive with anti-P3 serum. In crescentic glomerulonephritis, the collapsed glomerular tufts were stained normally with anti-HGBM and anti-P3 sera and weakly with anti-IV Col serum. In diabetic nephropathy, anti-HGBM serum stained the GBM in a double linear distribution without reacting with the expanded mesangium; anti-IV Col serum stained the mesangium and the GBM in a less clear double linear fashion while anti-P3 serum stained the GBM as single line. Thin membrane disease and Alport's syndrome had normal reactivity with all antisera. However, in one case of Alport's syndrome anti-HGBM and anti-P3 sera stained the GBM in a focal and segmental pattern, while normal staining with anti-IV Col serum was found. In lesions with adhesions and crescents the staining was positive for HGBM and IV Col and negative for P3; obsolescent glomeruli were stained with anti-HGBM and anti-P3 sera, and had diminished staining with anti-IV Col serum.The identification of the various structural glomerular antigens is useful in the classification of certain types of glomerular diseases. Further insight into the mechanisms underlying these conditions may be obtained in this way.  相似文献   
128.
A surgical case of an aggressive form of adenoid squamous cell carcinoma of the penis was studied. The histological features of the tumor originating from the coronal region of the penis showed a well differentiated keratinized squamous cell carcinoma in the superficial area, which transformed into, with a zone of transition in between, an alveolar structure in the deep invading portion and in the metastatic tumor in the inguinal lymph nodes. The alveolar lining cells exhibited an undifferentiated appearance with prominent nucleoli, frequent mitotic figures, and vascular invasion. These cells were neither dyskeratotic nor acanthotic as described in the literatures. Mucin was negative in the tumor cells and angiosarcoma was ruled out with a sliver impregnation technique. The patient took a rapid downhill course for the ordinary squamous cell carcinoma of the penis, and he expired eight months after penile amputation with a radiological evidence of lung metastasis. These unusual pathological features and an aggressive behavior of this tumor which were not hitherto described for adenoid squamous cell carcinomas necessitated this report. Autopsy was not performed.  相似文献   
129.
The effects of high and low dietary fat (20% vs. 0.5% corn oil), and of the prostaglandin synthetase inhibitor indomethacin (0.005% w/w), on tumour incidence, tumour growth, hormone-receptor status and growth-factor expression were examined in dimethylbenzanthracene (DMBA)-induced rat breast cancer. The high dietary-fat group showed a significantly higher tumour incidence, larger tumour size and larger number of bromodeoxyuridine(BrdU)-positive cells of tumours as compared with those in the low dietary-fat group. Indomethacin reduced tumour incidence significantly, but conversely increased the tumour size and the number of BrdU-positive cells in both the high and the low dietary-fat groups. No significant difference was noted in the hormone-receptor status of the tumours. Growth factors (TGF-alpha and IGF-II) were somewhat highly expressed in the high dietary-fat group as compared with the low dietary-fat group, but indomethacin rather reduced the growth-factor expression. It is concluded that high dietary fat stimulates tumour incidence and tumour proliferation, while indomethacin has dual effects: a stimulating effect on tumour proliferation, but an inhibiting effect on tumour incidence. It is also suggested that hormone-receptor status and growth-factor expression do not play an important role in their stimulating effects on tumour proliferation.  相似文献   
130.
Intraplacental choriocarcinoma is very rare, and is usually found only after maternal and fetal metastatic disease is identified. The purpose of this case report is to review the incidence and findings of intraplacental choriocarcinoma. A term placenta was investigated because the newborn was born with severe anemia (Hb 3.0 g/dL). A 2 cm nodule was noted on the surface of the amniotic membrane and grossly resembled an infarction. The tumor was examined microscopically with immunohistochemical staining for the alpha- and beta-human chorionic gonadotropin (alpha-hCG, beta-hCG) subunits, human placental lactogen (hPL) and Ki-67. Microscopically, the tumor consisted of necrotic areas with proliferation of atypical trophoblastic cells and destruction of the villi and capillaries. The cells were positive for the alpha-hCG, beta-hCG subunits, hPL and Ki-67, consistent with intraplacental choriocarcinoma. The mother and newborn were investigated for the presence of metastatic disease. Computed tomography scans and magnetic resonance imaging of the mother and infant were negative for metastatic disease. Choriocarcinoma, limited only to the placenta with no evidence of metastatic disease is very rare. Primary intraplacental choriocarcinoma may frequently be overlooked or missed, and choriocarcinoma may possibly arise in the placenta more often than in retained or persistent trophoblast following pregnancy.  相似文献   
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