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Protein tyrosine phosphatase ζ (PTPζRPTPβ) is a proteoglycan-type receptor-like protein tyrosine phosphatase specifically expressed in the brain. In addition to the transmembrane form (PTPζ-A), the extracellular splice variant (PTPζ-S) occurs as a major soluble chondroitin sulphate proteoglycan in the brain. We prepared antibodies which specifically recognize PTPζ-A and -S, and analysed the carbohydrate structures on the two PTPζ isoforms in the developing chick brain. lmmunoprecipitation experiments using these antibodies revealed that almost all of the keratan sulphate recognized by a monoclonal antibody (5D4) was exclusively bound to PTPζ-A and PTPζ-S. Addition of keratan sulphate to these proteoglycans markedly increased from embryonic day (E) 11, in contrast to the addition of LeX and HNK-1 carbohydrates, which gradually increased during development in accordance with expression of the core proteins, suggesting that keratan sulphate modification plays some specific roles. Moreover, at the early embryonic stage keratan sulphate was observed only in several restricted regions, especially at boundary regions such as the roof plate of the tectum, the zona limitans intrathalamica in the diencephalon, and the mesencephalon-metencephalon boundary. At the mesencephalon-metencephalon boundary, keratan sulphate modification of PTPζ isoforms was specifically observed from E3 to E6 on a ring of cells encircling the neural tube and their radially oriented processes, which were identified as radial glial fibres. This expression pattern of keratan sulphate spatiotemporally corresponded well to the formation of the fovea isthmi, a groove separating the mesencephalon from the metencephalon. These results suggest that carbohydrates including keratan sulphate on PTPζ isoforms play important roles in brain development by modulating the cell-cell and/or cell-substrate interactions mediated by these molecules.  相似文献   
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A 64-year-old man was referred to our hospital with Methicillin-resistant Staphylococcus aureus (MRSA) infection following infrainguinal arterial reconstruction. As repeated MRSA sepsis occurred, we decided to remove the infected graft with distal revascularization via circuitous graft tunneling to avoid serious infections and allow limb salvage. An iliofemoro bypass was performed via an extra-anatomical bypass, from just below the iliac crest into the musculus quadriceps femoris using an 8 mm-ringed polyester gelatin polypropylene tube graft, with complete debridement of a groin infection. Postoperative 3-dimentional CT angiography revealed that the prostheses was patent and the patient had an uneventful postoperative course. We concluded that this extra-anatomical bypass was a safe procedure and an excellent option for patients with an infected vascular prosthetic graft in the groin after previous revascularization, like in our case with no available autogeneous vein grafts.  相似文献   
5.
Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG-positive seminoma) is regarded as more malignant than marker-negative seminoma, although Its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (β-hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the Immunohistochemical expression of β-hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the Invasive status, metestatic status and poor outcome, while that of the serum β-hCG level correlated only to the metastatic status. Immunohistochemical expression of β-hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells In 36 tumors. Expression was not associated with the malignancy potential, except where the expression In mononuclear cells Inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level Indicates the pressnce of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma.  相似文献   
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The acute onset of peritoneal signs and shock in a 7year-old boy who had been hit in the epigastrium by a log-seesaw mandated surgical treatment. Enhanced computed tomography (CT) demonstrated complete laceration of the pancreas as well as duodenal injury, and a duodenoduodenostomy with distal pancreaticogastrostomy was subsequently performed. Temporary external drainage of the stomach and distal pancreas led to an uneventful recovery in the early postoperative period. Although the patient's postoperative development was appropriate for his age, the orifice of the distal pancreas spontaneously closed 2.5 years following surgery. We present this report to stress the fact that every effort should be made to preserve the pancreas following abdominal injury in children.  相似文献   
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To determine the healing potential and healing process of torn supraspinatus tendons, in situ hybridization was used to localize cells containing α1 type-I procollagen mRNA. Biopsy specimens of torn supraspinatus tendons from 19 patients with complete-thickness tears and 13 patients with incomplete-thickness tears were obtained during surgery. Four macroscopically normal supraspinatus tendons were obtained to serve as normal controls. Specimens were fixed in 10% buffered formalin and embedded in paraffin. A 22-mer oligonucleotide probe was labeled with digoxigenin and used as an in situ marker. The labeled cells were mainly composed of tenocytes and undifferentiated mesenchymal cells. In complete-thickness tears, the labeled cells at the proximal tendon stumps in the specimens that were obtained less than 4 months after trauma were significantly more abundant than in the specimens obtained 4 months or more after trauma. However, the number of labeled cells was maintained at the torn portion even in long-standing incomplete-thickness tears. The labeled cells at the margins of concomitant intratendinous extensions of the tears were detected even in the long-standing tears. The intratendinous extensions exhibited more labeled cell than were bursal-side or joint-side layers of the tendon substance in the incomplete-thickness tears (p < 0.05). The torn supraspinatus tendon may possess an intrinsic healing capability in the intermediate and late phases of tendon healing. Incomplete-thickness tears and concomitant intratendinous extensions can continue to rupture after the initial injury.  相似文献   
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We examined the effects of a new inotrope, OPC-8212 (OPC: 2(1H)-quinolinone), on coronary sinus flow (CSF), myocardial oxygen consumption, myocardial lactate extraction ratio (LER), cardiac index (CI) and pulmonary arterial diastolic pressure (PADP) in eleven patients with prior myocardial infarction. Measurements were taken before (control) and 8 hours after administration of OPC (480 mg, p.o.). A cardiac function curve was obtained in each stage with rapid intravenous administration of 500 ml of saline (loaded state) after baseline measurements. There was a significant increase in the cardiac index and decrease in the pulmonary arterial diastolic pressure in the loaded state after OPC. Thus the ventricular function curve was shifted to the left and showed a steep incline, indicating an increased inotropic state. On the other hand, myocardial oxygen consumption and myocardial lactate extraction ratio were unchanged. Thus we concluded that OPC improved cardiac performance without increasing myocardial oxygen consumption.  相似文献   
9.
A 76-year-old female was admitted with many bullae and erythema on her trunk and extremities. A biopsy specimen showed significant intercellular edema in the lower epidermis and eosinophilic infiltration into the dermis and the epidermis. Immunofluorescent staining revealed the deposition of IgG in the intercellular area of her prickle cells. From these histologic findings and the typical clinical features, we diagnosed her as having pemphigus vulgaris. Examination of her blood revealed that she also suffered from autoimmune hemolytic anemia. Despite intensive treatment with prednisolone, she finally died. This case is of interest because of its rarity and the TNFα detected significantly in the blister fluid of this patient.  相似文献   
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Recent studies have indicated that bone marrow stromal cells (BMSC) have the potential to improve neurologic function when transplanted into animal models of central nervous system disorders. However, how the transplanted BMSC restore the lost neurologic function is not clear. In the present study, therefore, we aimed to elucidate whether BMSC express the neuron-specific gamma-aminobutyric acid (GABA) receptor when transplanted into brain that has been subjected to cerebral infarction. METHODS: The BMSC were harvested from green fluorescent protein-transgenic mice and were cultured. The mice were subjected to permanent middle cerebral artery occlusion. The BMSC or vehicle was transplanted into the ipsilateral striatum 7 d after the insult. Using autoradiography and fluorescence immunohistochemistry, we evaluated the binding of 125I-iomazenil and the expression of GABA receptor protein in and around the cerebral infarct 4 wk after transplantation. RESULTS: Binding of 125I-iomazenil was significantly higher in the periinfarct neocortex in the BMSC-transplanted animals than in the vehicle-transplanted animals. Likewise, the number of the GABAA receptor-positive cells was significantly higher in the periinfarct neocortex in the BMSC-transplanted animals than in the vehicle-transplanted animals. A certain subpopulation of the transplanted BMSC expressed a neuron-specific marker, microtubule-associated protein 2, and the marker protein specific for GABAA receptor in the periinfarct area. CONCLUSION: These findings suggest that BMSC may contribute to neural tissue regeneration through migrating toward the periinfarct area and acquiring the neuron-specific receptor function.  相似文献   
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