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61.
Release of norepinephrine (NE) and ATP from the guinea pig vas deferens evoked by ouabain in combination with monensin or by high KCl was measured by a high-pressure liquid chromatography-ECD and luciferin-luciferase assay, respectively. Ouabain (10-100 microM) induced a concentration-dependent liberation of NE, which was enhanced by 10 microM monensin, a Na+-ionophore. The marked NE release elicited by the combined administration of both the drugs was unaffected by Ca++-removal but was reduced by lowering Na+ from the medium. This NE release in the Ca++-free medium was diminished markedly after treatment with 6-hydroxydopamine or reserpine and in low-temperature (25 degrees C) medium. This release was also decreased by ruthenium red (10-30 microM), an uptake inhibitor of Ca++ to mitochondria, and carbonyl cyanide-m-chlorophenyl hydrazone (10 microM), a metabolic inhibitor. On the other hand, 100 mM KCl caused a moderate, extracellular Ca++-dependent release of NE. ATP-outflow from the tissue evoked by 100 microM ouabain plus 10 microM monensin was almost unaltered by Ca++-removal but was inhibited by 6-hydroxydopamine or prazosin (0.3 microM), whereas release induced by high KCl was reduced by 6-hydroxydopamine and Ca++-free medium but was unaffected by prazosin. ATP/NE ratios at respective maximum effluxes evoked by 100 mM KCl and ouabain plus monensin were 6.59 and 0.22, respectively. These findings suggest that there may be more than one site of corelease for NE and ATP. Ouabain plus monensin seems to produce an extracellular Ca++-independent neuronal release of NE and ATP from the cytoplasmic and vesicular storage sites which predominantly release NE.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
62.
Background:
Although ice slush cooling or ex situ perfusion with bench surgery is most widely used for protecting ischemic renal damage which possibly accompanies complicated nephron-sparing surgery, each has its own disadvantages. The former does not allow excessively long ischemia and the laller requires complicated procedures as autotransplantation. In order to mitigate against these problems, we devised a novel method of in situ renal perfusion with intracellular hyperosmolar solution.
Methods:
One renal segmental artery mainly supplying a tumor was isolated and cannulated with a small feeding tube. The tube was introduced through a small arteriotomy incision directed towards the proximal side, advanced until its tip remained in the main or first branch of the renal artery, and then it was anchored to that artery. After the main renal artery and vein were clamped, the kidney was perfused with cold Euro-Collins' solution through the tube, while the venous blood and perfusate were drained from the left gonadal vein or small venotomy incision of the right renal vein. Results: In one case of renal cell carcinoma and three cases of angiomyolipoma, two of which ruptured, nephron-sparing surgery was carried out under in situ hyperosmolar perfusion. Ischemic time of these four cases was an average of 96 minutes, varying from 45 to 145 minutes. All the kidneys functioned well postoperatively,
Conclusions:
The method presented here is very simple, requires no unusual dexterity and safely allows for a long period of renal ischemia. This method is best indicated in cases where simple clamping of the renal pedicle with ice-slush cooling appears insufficient, yet ex situ surgery with autotransplantation seems excessive.  相似文献   
63.
We report a case of carcinosarcoma ex recurrent pleomorphic adenoma in the submandibular region of a 56-year-old Japanese man. He presented with a 2-year history of a rapidly growing mass in the submandibular region. He reported undergoing excision of a nodule in the same region 10 years earlier. Incisional biopsy confirmed the diagnosis of pleomorphic adenoma. The lesion was excised surgically. The resected tumor measured 40 x 20 mm and was composed of two large nodules and multiple small satellite nodules in the subcutaneous tissue. Histopathologically, one large nodule was carcinosarcoma while the other large nodules and small satellite nodules were pleomorphic adenoma. The former large nodule showed a variegated pattern with carcinomatous components (poorly differentiated adenocarcinoma, salivary duct carcinoma, squamous cell carcinoma and undifferentiated carcinoma) and sarcomatous components (spindle cell sarcoma, chondrosarcoma, liposarcoma and rhabdomyosarcoma). Based on the clinical history and histopathology, we consider the lesion to have originated from recurrent pleomorphic adenoma.  相似文献   
64.
The laminins belong to a family of trimeric basement membrane glycoproteins with multiple domains, structures, and functions. Endothelial cells bind laminin-1 and form capillary-like structures when plated on a laminin-1-rich basement membrane matrix, Matrigel. Laminin-1 is composed of 3 chains, alpha1, beta1, and gamma1. Because laminin-1 is known to contain multiple biologically active sites, we have screened 156 synthetic overlapping peptides spanning the entire laminin gamma1 chain for potential angiogenic sequences. Only 7 of these peptides, designated as C16, C25, C30, C38, C64, C75, and C102, disrupted the formation of capillary-like structures by human umbilical vein endothelial cells on Matrigel. Dose-response experiments in the presence of 50 to 200 microg/mL showed that tube formation was prevented by most peptides at 150 and 200 microg/mL, except for C16, which showed strong activity at all concentrations. Active peptides promoted vessel sprouting from aorta rings and angiogenesis in the chick chorioallantoic membrane assay. In addition, the active peptides also promoted endothelial cell adhesion to dishes coated with 0.1 microg of peptide and inhibited attachment to laminin-1 but not to plastic or fibronectin. Four of the active peptides, C25, C38, C75, and C102, may have cell-type specificity with endothelial cells, since they did not promote PC12 neurite outgrowth or adhesion of B16-F10 melanoma and human submandibular gland cells. These results suggest that specific laminin gamma1-chain peptides have angiogenic activity with potential therapeutic applications.  相似文献   
65.
66.
Clinical results of cases of hypopharyngeal carcinoma treated from 1966 to 1990 at Kyushu University Hospital were investigated. In 1966-1972, all cases were treated with only radical operation. We used FAR therapy since 1972, and preoperative chemotherapy (CDDP and Peplomycin) in addition to FAR therapy since 1984. The crude five-year survival rate of the operative therapy-group (25 cases in 1966-1972) was 24%, and that of the FAR therapy-group with or without operation (47 cases in 1972-1980) was 38%. Although it was cumulative survival rate by Kaplan-Meier's method, the five-year survival rate of the group (16 cases in 1984-1990) treated with a combination of FAR therapy, preoperative-chemotherapy, and operation was 76%. The improvement in the survival rate and the role of preoperative treatment (FAR therapy and chemotherapy) are discussed.  相似文献   
67.
68.
Thromboxane A2 (TxA2) is a potent platelet aggregator and vascular or bronchial constrictor. DP-1904, a newly synthesized imidazol TxA2 synthetase inhibitor, is a potent and long-acting agent. The present investigation was conducted to explore the effect of DP-1904 on the contractile or relaxing responses in guinea pig trachea and lung tissue strips induced by various vasoactive substances. Fourteen guinea pigs, weighing 300-350 g, were sacrificed. Trachea and lungs were removed, cut spirally, set up in bioassay glass jackets and superfused with Krebs-Henseleit solution at 37 degrees C, saturated with oxygen and carbon dioxide. Contraction of tissues was detected by an isotonic transducer and displayed on a polyrecorder. Arachidonic acid-induced relaxing responses in guinea pig trachea strips were attenuated significantly by the continuous infusion of DP-1904 in a dose-dependent fashion. Arachidonic acid-induced contractile responses in guinea pig lung strips were attenuated significantly by the continuous infusion of DP-1904, dose-dependently. Acetylcholine-, histamine- and prostaglandin F2 alpha-induced contractile responses in guinea pig lung and trachea strips were attenuated significantly by the continuous infusion of DP-1904, dose-dependently. The above results suggest that DP-1904 might be a useful therapeutic agent for the treatment of chronic obstructive lung diseases.  相似文献   
69.

Purpose

Helicobacter pylori infection is acquired by oral ingestion. H. pylori has been reported to be present in the palatine tonsils. To clarify the route and mode of infection, the prevalence of tonsillar H. pylori was evaluated, and an attempt was made to culture tonsillar H. pylori.

Methods

In a prospective study, 55 patients with recurrent pharyngotonsillitis or IgA nephropathy underwent a tonsillectomy. The carbon 13-urea breath test and enzyme-linked immunosorbent assay for the detection of H. pylori IgG antibodies in the serum were performed. Tonsillar H. pylori was cultured under conventional culture conditions for gastric H. pylori with or without the following shock methods; heat shock, hydrogen-peroxide-degrading compounds, or parasitizing amoebae. Immunofluorescence and immunoelectron microscopy using antibodies against H. pylori and cytotoxin-associated antigen A were used to identify tonsillar H. pylori.

Results

H. pylori in the coccoid form was present in tonsillar crypts. Of 55 patients, 43 (78.2%) had tonsillar H. pylori, and 15 (27.3%) were infected with gastric H. pylori. All patients with gastric H. pylori also had tonsillar H. pylori (p < 0.01). Cytotoxin-associated antigen A was observed in 38 (88.4%) of 43 tonsillar H. pylori. Tonsillar H. pylori could not be cultured in any culture conditions. All patients with IgA nephropathy had tonsillar H. pylori (p < 0.01).

Conclusions

The present research might provide some insight into clarifying the route and mode of H. pylori infection. Our findings may indicate that tonsillar H. pylori is one of the antigens causative of IgAN.  相似文献   
70.
BACKGROUND: Serine proteases have important roles in tumor invasion and metastasis, and their inhibitors, serine protease inhibitors (serpins), are attractive targets for therapeutic strategies. On chromosome 18q21, there is a cluster of serpins: maspin, headpin, and squamous cell carcinoma antigen 1 (SCCA1)/SCCA2. Others and we have reported that the expression of these serpins is down regulated in head and neck squamous cell carcinoma (HNSCC) cells compared with normal squamous epithelial cells. In this study, we hypothesized that expression of SCCA1 is biologically disadvantageous to HNSCC cells. METHODS: HNSCC cell lines were transfected with a mammalian expression vector with SCCA1 cDNA. In vitro proliferation, migration, or invasive potential (matrigel assay) of the transfectants were assayed. In addition, the in vivo growth and invasion was analyzed using the floor-of-mouth model of nude mice. RESULTS: SCCA1 expression did not alter the in vitro growth rate of established HNSCC cells. However, SCCA1 expression significantly inhibited the in vitro invasion in matrigel assays. Furthermore, the in vivo growth and invasion in nude mice was also inhibited by SCCA1 expression. CONCLUSIONS: Overexpression of SCCA1 in a HNSCC cell line inhibited its invasive potential. Loss of expression of the serpin SCCA1 may play a role in the malignant progression of HNSCC.  相似文献   
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