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991.
K Fukushima S Hara-Kuge T Ohkura A Seko H Ideo T Inazu K Yamashita 《Canadian Metallurgical Quarterly》1997,272(16):10579-10584
We found that 35S-labeled recombinant human interleukin-1beta (rhIL-1beta) binds phosphatidylinositol-specific phospholipase C-treated human placental alkaline phosphatase, phosphatidylinositol-specific phospholipase C-treated trypanosome surface variant glycoproteins, and urinary uromodulin immobilized on plates or immobilized on CNBr-activated Sepharose 4B. The interaction between rhIL-1beta and these glycoproteins was lectin-like, since it was inhibited in the presence of specific saccharides, i.e. mannose 6-phosphate or synthetic Ac-NH.CH2.CH2. PO4--->6Manalpha1-->(+/-2Manalpha1-->+/-6Manalpha1-->) propyl at about 1 microM. On the other hand, a wide variety of compounds including biantennary sugar chains derived from these glycoproteins as well as ethanolamine phosphate, inositol phosphate, mannose 6-sulfate, mannose 1-phosphate, glucose 6-phosphate, and mannitol 6-phosphate did not show any inhibitory effect at concentrations up to 1 mM. These results indicate that rhIL-1beta interacts with these glycoproteins via the mannose 6-phosphate diester of glycans on the glycosylphosphatidylinositol (GPI) anchor. Furthermore, when monolayers of polarized Madin-Darby canine kidney cells on polycarbonate filter membranes were incubated with 35S-rhIL-1beta in either the apical or basolateral chamber, 35S-interleukin-1beta was found to bind specifically to the apical membranes with a Ka value of 4.6 x 10(7) M-1, and the specific interaction was inhibited by 1 microM mannose 6-phosphate. Since the mannose 6-phosphate diester moiety exists only in the GPI glycans on plasma membranes, it was evident that interleukin-1beta can directly interact with the mannose 6-phosphate diester component of the intact glycan of GPI anchors on plasma membranes. 相似文献
992.
JA Burger A Ochs K Wirth DP Berger R Mertelsmann R Engelhardt M Roessle K Haag 《Canadian Metallurgical Quarterly》1997,8(2):200-202
BACKGROUND: The increase in portal vascular resistance is a significant complication of metastatic disease to the liver or locally advanced cancer, e.g., biliary cancer. PATIENTS AND METHODS: This paper describes the successful palliative treatment of two cancer patients with portal hypertension presenting with the symptoms of tense ascites, mesenteric congestion, and severe variceal bleeding. By creating a stenttract between a hepatic vein and a main branch of the portal vein and/or by placing an extendable stent into the portal vein, the transjugular intrahepatic portosystemic stent-shunt (TIPS) technique was used to decompress the portovascular system. RESULTS: The TIPS-technique offers a new, safe and effective palliation for malignant portal hypertension. In both patients, the symptoms of the portal hypertension disappeared after the procedure. This was accompanied by a significant improvement of the patients performance status allowing an early ambulation. CONCLUSION: Our findings demonstrate the feasibility and effectiveness of the TIPS procedure as a minimal invasive treatment for portal vein decompression in selected tumor patients. 相似文献
993.
R Middendorff D Müller S Wichers AF Holstein MS Davidoff 《Canadian Metallurgical Quarterly》1997,82(12):4154-4161
Previous studies have demonstrated that nitric oxide (NO) influences Leydig cell function. Here we provide evidence for NO production and activity in seminiferous tubules and blood vessels of the human testis. By immunohistochemistry, the soluble guanylyl cyclase (sGC), the intracellular NO receptor, and the second messenger, cyclic guanosine monophosphate (cGMP), were detected in myofibroblasts of the peritubular lamina propria in Sertoli cells, as well as in endothelial and smooth muscle cells of testicular blood vessels. Performed with isolated tubules and blood vessels, the biological activity of sGC could be proved by cGMP generation in response to treatments with the NO donor, sodium nitroprusside. The endothelial and neuronal subtypes of NO synthase (NOS) were localized immunohistochemically to the same cell types that express sGC and cGMP. In isolated tubules and vessels, the presence of endothelial NOS and neuronal NOS was confirmed by immunoblotting, and NOS activity was demonstrated by decreased cGMP production upon incubation with the NOS inhibitor L-nitro arginine methylester. These findings show that peritubular cells, Sertoli cells, and testicular blood vessels may be sites of NO production and activity, possibly involved in relaxation of seminiferous tubules and blood vessels to modulate sperm transport and testicular blood flow, respectively. 相似文献
994.
H Kato T Takashima H Kishikawa S Emura K Ohmori 《Canadian Metallurgical Quarterly》1997,51(8):489-490
We studied urinary N-acetyl-beta-D-glucosaminidase (NAG) in the early stage of diabetic nephropathy in 27 non-insulin-dependent diabetes mellitus (NIDDM) patients with a microalbumin level below 20 mg on 24-hour urine sample. Microalbumin and NAG excretion were measured in 24-hour urine samples collected on three separate occasions within seven days of admission. Creatinine clearance was determined simultaneously. There was a significant negative correlation between the creatinine clearance and 24-hour urinary NAG (r = -0.38, p < 0.05). Elevation of urinary NAG may indicate decreased renal function during early stage NIDDM nephropathy. 相似文献
995.
R Kalluri K Meyers A Mogyorosi MP Madaio EG Neilson 《Canadian Metallurgical Quarterly》1997,8(11):1795-1800
A 68-year-old Caucasian woman presented to the hospital with nodular pulmonary infiltrates and acute renal failure. Wegener's granulomatosis was initially considered to be most likely because of the presence of increased serum levels of c-anti-neutrophil cytoplasmic antibodies (c-ANCA). A consultation through the Internet after a renal biopsy demonstrated crescentic, necrotizing glomerulonephritis and linear deposits of immunoglobulin G (IgG) and complement C3, typical of anti-glomerular basement membrane (GBM) disease. Hemodialysis was instituted; however, the patient suddenly developed a massive cerebral hemorrhage and died before full therapy could take effect. Postmortem analysis of the patient's sera revealed high titers of IgG against the alpha 3 NC1 domain of type IV collagen. Serologic evidence of both p-ANCA and anti-GBM antibodies are becoming more frequently recognized in the setting of rapidly progressive glomerulonephritis. The patient reported here had the unusual combination of c-ANCA antibodies with anti-GBM disease, and this association raises complex questions regarding the pathogenesis of this type of renal injury. 相似文献
996.
T Tillmann K Kamino C Dasenbrock H Ernst M Kohler G Morawietz E Campo A Cardesa L Tomatis U Mohr 《Canadian Metallurgical Quarterly》1997,49(3-4):197-200
An experiment using 4279 CBA/J mice of two generations was carried out to investigate the influence of parental preconceptual exposure to X-ray radiation or to chemical carcinogens. Microchips were implanted subcutaneously in the dorsolateral back for unique identification of each animal. The animals were kept for lifespan under standard laboratory conditions. In 36 mice a circumscribed neoplasm occurred in the area of the implanted microchip. Females were significantly more frequently affected than male mice. An influence of age or different treatment on the s.c. tumour incidence in two mice generations could not be observed. Macroscopically, firm, pale white nodules up to 25 mm in diameter with the microchip in its center were found. Microscopically, soft tissue tumours such as fibrosarcoma and malignant fibrous histiocytoma were detected. 相似文献
997.
998.
GB Lipford T Sparwasser M Bauer S Zimmermann ES Koch K Heeg H Wagner 《Canadian Metallurgical Quarterly》1997,27(12):3420-3426
Certain bacterial immunostimulatory (i.s.) DNA sequences containing unmethylated CpG motifs stimulate antigen-presenting cells (APC) to express a full complement of costimulatory molecules and to produce cytokines including interleukin (IL)-12 and tumor necrosis factor (TNF)-alpha. While IL-12 is key to their T helper cell (Th)1-promoting adjuvant activity, secretion of toxic levels of TNF-alpha is harmful in that it promotes toxic shock. Given the beneficial as well as harmful consequences of i.s. DNA, we investigated the possibility of identifying DNA sequences, i.e. CpG oligodeoxynucleotides (ODN) which differentially activate IL-12 versus TNF-alpha cytokine production in APC. Here, we describe an i.s. DNA sequence with these characteristics. While its potential to induce IL-12 is preserved, its ability to trigger TNF-alpha release is strongly curtailed both in vitro and in vivo. I.s. DNA could be segregated into lethal and non-lethal in a mouse toxic shock model. The non-toxic i.s. DNA was useful as an adjuvant, thus allowing cytotoxic T cell responses to the soluble protein ovalbumin and conferring a resistant Th 1 phenotype to BALB/c mice lethally infected with Leishmania major. This i.s. CpG motif may thus be prototypic for a useful immunostimulating DNA sequence that lacks harmful side effects. 相似文献
999.
1000.
Sarkar T.K. Su C. Adve R. Salazar-Palma M. Garcia-Castillo L. Boix R.R. 《Antennas and Propagation Magazine, IEEE》1998,40(5):49-68
The objective of this paper is to present the subject of wavelets from a filter-theory perspective, which is quite familiar to electrical engineers. Such a presentation provides both physical and mathematical insights into the problem. It is shown that taking the discrete wavelet transform of a function is equivalent to filtering it by a bank of constant-Q filters, the non-overlapping bandwidths of which differ by an octave. The discrete wavelets are presented, and a recipe is provided for generating such entities. One of the goals of this tutorial is to illustrate how the wavelet decomposition is carried out, starting from the fundamentals, and how the scaling functions and wavelets are generated from the filter-theory perspective. Examples (including image compression) are presented to illustrate the class of problems for which the discrete wavelet techniques are ideally suited. It is interesting to note that it is not necessary to generate the wavelets or the scaling functions in order to implement the discrete wavelet transform. Finally, it is shown how wavelet techniques can be used to solve operator/matrix equations. It is shown that the “orthogonal-transform property” of the discrete wavelet techniques does not hold in numerical computations 相似文献