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Summary In order to examine its clinical efficacy, recombinant human interferon- (rIFN-) was instilled intravesically into 51 patients with superficial bladder cancer. Ten patients, who received intermittent intravesical instillation at a dose of (3–36) × 106 U rIFN- on days 1–3 every week, showed no response. Thirty-two patients received intravesical instillation at a dose of (3–36) × 106 U every day for 10–20 days. Eight patients showed partial response, indicating an efficacy rate of 25%. Nine patients received divided doses of 18 × 106 U twice a day every day for 10–20 days. Six patients showed partial response, indicating an efficacy rate of 67%. This value was significantly higher than that obtained by administering divided doses. The response to intravesical instillation therapy with rIFN- varies with treatment protocol. Frequent and longer exposure to rIFN- may induce better regression of superficial bladder cancer. Six incidences of side-effects were found in five cases (9.8%): pollakiuria in one, pain on micturition in two, fever in two, and eruption in one case. All of these side-effects were slight and reversible after drug withdrawal. Laboratory tests showed only a few changes with low severity. Thus, rIFN- is potentially a new drug for instillation therapy of superficial bladder cancer, in view of the absence of adverse effects.  相似文献   
33.
Summary During the course of studies to characterize mutations of the CYP17 gene that cause the 17-hydroxylase-deficient form of congenital adrenal hyperplasia we have discovered two ostensibly unrelated Mennonite families in which affected individuals are homozygous for the same mutation. The defect is a four-base duplication in exon 8 of the CYP17 gene, which alters the reading frame encoding the C-terminal 26 animo acids of cytochrome P45017.  相似文献   
34.
Nonspecific cross-reacting antigen-2 (NCA-2) is a glycoprotein purified from meconium as a closely correlated entity with carcinoembryonic antigen (CEA). As in the case of CEA, only asparagine-linked sugar chains are included in NCA-2. In order to elucidate the structural characteristics of the sugar chains of NCA-2, they were quantitatively released from the polypeptide backbone by hydrazinolysis and reduced with NaB3H4 after N-acetylation. The radioactive oligosaccharides were fractionated by paper electrophoresis, serial chromatography on immobilized lectin columns, and Bio-Gel P-4 (under 400 mesh) column chromatography. Structures of the oligosaccharides were estimated from the data of the binding specificities of immobilized lectin columns and the effective size of each oligosaccharide determined by passing through a Bio-Gel P-4 column and were then confirmed by endo-beta-galactosidase digestion, sequential digestion with exoglycosidases with different aglycon specificities, and methylation analysis. NCA-2 contains a similar number (27 mol) of sugar chains in one molecule compared with CEA (24-26 mol). However, all sugar chains of NCA-2 were complex-type in contrast to CEA, approximately 8% of the sugar chains of which were high mannose-type (Yamashita, K., Totani, K., Kuroki, M., Matsuoka, Y., Ueda, I., and Kobata, A. (1987) Cancer Res. 47, 3451-3459). About 80% of the oligosaccharides from NCA-2 contain bisecting N-acetylglucosamine residues, and the percent molar ratio of mono-, bi, tri, and tetraantennary oligosaccharides was 2:14:57:27. (+/- Fuc alpha 1----2)Gal beta 1----4(+/- Fuc alpha 1----3)GlcNAc, (+/- Fuc alpha 1----2)Gal beta 1----3(+/- Fuc alpha 1----4)GlcNAc, (+/- Fuc alpha 1----2)Gal beta 1----4(+/- Fuc alpha 1----3)GlcNAc beta 1---- 3Gal beta 1----4GlcNAc, (+/- Fuc alpha 1----2)Gal beta 1----3(+/- Fuc alpha 1----4)GlcNAc beta 1---- 3Gal beta 1----4GlcNAc, and GalNAc beta 1----3Gal beta 1----3GlcNAc beta 1----3Gal beta 1----4GlcNAc were found as their outer chain moieties. Approximately 60% of the oligosaccharides from NCA-2 contain the Gal beta 1----4 or 3GlcNAc beta 1----3Gal beta 1----4GlcNAc beta 1----group in their outer chains.  相似文献   
35.
A minibead method for detection of membrane lectins   总被引:1,自引:0,他引:1  
Membrane lectins are being increasingly implicated in many biological phenomena. Previous methods for detection of these substances are applicable only to homogeneous cell populations. We have now developed a method that permits morphological identification of lectin-bearing cells in heterogeneous cell populations. Amide-modified latex minibeads (0.345 or 0.532 micron) were activated with glutaraldehyde and then covalently bound to p-aminophenyl derivatives of various sugars. When the probe thus constructed was incubated with cell systems known to bear well-defined membrane lectins (galactosyl receptors in hepatocytes, mannosyl receptors in macrophages), binding occurred and could be visualized by scanning electron microscopy. Binding was inhibited in the presence of excess soluble sugar, indicating the specificity of reaction. Incubation of a mixture of two different-sized probes with two different cell types led to segregation of the probes. This method also permits semiquantification of binding.  相似文献   
36.
M Matsuoka  K Yoshida  T Maeda  S Usuda  H Sakano 《Cell》1990,62(1):135-142
We have characterized circular DNA in mouse splenocytes treated with the mitogen lipopolysaccharide (LPS) and various cytokines, including transforming growth factor beta (TGF-beta) and interleukin 4 (IL-4). Using probes of immunoglobulin heavy chain constant genes (CH), excision products of class switch recombination were identified. The majority of the clones contained the 3' portion of the switch mu (S mu) region and the 5' portion of other switch regions. Some clones contained 3'-S gamma sequences instead of 3'-S mu. This indicates that isotype switching may occur not only from C mu, but also from one of the C gamma genes to other CH genes further down-stream. In the presence of LPS, the cytokine TGF-beta enhanced the detection of 5'-S alpha-positive clones, while the lymphokine IL-4 enhanced 5'-S gamma 1 positives. The data support the notion that TGF-beta and IL-4 can direct isotype-specific class switching.  相似文献   
37.
A novel method is proposed for the evaluation of the activity of an antifungal agent administered as a gas. This system is composed of a batch-flow type reaction vessel, a gas flow system, and a microscopic observation system. The agar plate was prepared on the ceiling of the reaction vessel, and the mycelium of a fungus (Aspergillus niger or Rhizoctonia solani) was inoculated onto it. After preincubation at 25 degrees C for 24 h, the reaction vessel was connected to the gas flow system. An appropriate hypha was selected, and its elongation rate was measured. Then a sample holder containing an antifungal compound was inserted into the reaction vessel from the side hole to saturate the atmosphere inside with its vapor. The retardation or inhibition of the hypha elongation was observed on a television monitor and recorded on a video tape recorder. The antifungal compound was then removed, and the reaction vessel was flushed with air. If the hypha lived, it began to elongate again. By this method, antifungal activity of seven odor compounds could be evaluated quantitatively within several hours.  相似文献   
38.
To explore the mechanisms for the natriuretic effects of a neutral endopeptidase inhibitor, candoxatril, the concentration of atrial natriuretic peptide (ANP) and its molecular forms in the urine of Dahl salt-sensitive (S) rats were examined. Candoxatril-induced natriuresis (+120%, p less than 0.05) was associated with a marked increase in the urinary ANP excretion (+1200%, p less than 0.05). Analysis by Sephadex G-50 gel filtration revealed that molecular weight of the major fraction of immunoreactive (ir-) ANP in the plasma of candoxatril-treated Dahl S rats was 3K, whereas that in the urine was 2.5 K. Further analysis by reverse phase high performance liquid chromatography showed that ir-ANP in the plasma of Dahl S rats was alpha-rANP (1-28), while that in the urine from rats treated with candoxatril was alpha-rANP (1-25). These results indicate that candoxatril inhibits the complete degradation of ANP in the kidney, thereby increasing the amount of biologically active ANP reaching the distal nephron and contributing to natriuresis.  相似文献   
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Abstract: The cell adhesion molecule L1 is a multifunctional protein in the nervous system characterizing cell adhesion, migration, and neurite outgrowth. In addition to full-length L1, we found an alternatively spliced variant lacking both the KGHHV sequence in the extracellular part and the RSLE sequence in the cytoplasmic part of L1. This L1 variant was expressed exclusively in nonneuronal cells such as Schwann cells, astrocytes, and oligodendrocytes, in contrast to the expression of the full-length L1 in neurons and cells of neuronal origin. To investigate the functions of the L1 variant, we established cell lines transfected with a cytoplasmic short L1 (L1cs) cDNA that lacks only the 12-bp segment encoding for the RSLE sequence. The promoting activities of homophilic cell adhesion, neurite outgrowth, and neuronal cell migration of L1cs-transfected cells (L4-2) were similar to those of full-length L1-transfected cells (L3-1), but the cell migratory activity of L4-2 itself was clearly lower than that of L3-1. In conclusion, the short form of L1 is a nonneuronal type, in contrast to the neuronal type of the full-length L1. Deletion of the four amino acids RSLE in the cytoplasmic region of L1 markedly reduced cell migratory activity, suggesting an importance of the RSLE sequence for the signaling events of neuronal migration mediated by L1.  相似文献   
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