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131.
132.
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   
133.
Rat insulin-like growth factor-I (IGF-I), a serum polypeptide with growth promoting activity, was isolated from rat serum by a combination of acid/ethanol extraction, affinity chromatography, and a series of reversed phase high performance liquid chromatography, cation exchange, and reversed phase. All peptide fragments produced by chymotrypsin digestion of reduced and carboxymethylated rat IGF-I were amino acid sequenced and compared with the sequence of human IGF-I. Three out of 70 of the rat amino acid residues differed from those of human IGF-I as follows: Asp20----Pro, Ser35----Ile and Ala67----Thr. Purified rat IGF-I cross-reacted with polyclonal anti-human IGF-I antibody 75% as compared to human IGF-I, but it cross-reacted only 3% with monoclonal anti-human IGF-I antibody. Thus, it is possible to monitor the metabolic fate of human IGF-I, when injected into rats, without interference by endogenous rat IGF-I. Rat IGF-I showed 65% activity in the radioreceptor, 28.6% activity in the lipogenesis and 22.5% activity in the free fatty acid release inhibition assays as compared to human IGF-I on a protein quantity basis.  相似文献   
134.
The site in calcineurin, the Ca2+/calmodulin (CaM)-dependent protein phosphatase, which is phosphorylated by Ca2+/CaM-dependent protein kinase II (CaM-kinase II) has been identified. Analyses of 32P release from tryptic and cyanogen bromide peptides derived from [32P]calcineurin plus direct sequence determination established the site as -Arg-Val-Phe-Ser(PO4)-Val-Leu-Arg-, which conformed to the consensus phosphorylation sequence for CaM-kinase II (Arg-X-X-Ser/Thr-). This phosphorylation site is located at the C-terminal boundary of the putative CaM-binding domain in calcinerin (Kincaid, R. L., Nightingale, M. S., and Martin, B. M. (1988) Proc. Natl. Acad. Sci. U. S. A. 85, 8983-8987), thereby accounting for the observed inhibition of this phosphorylation when Ca2+/CaM is bound to calcineurin. Since the phosphorylation site sequence also contains elements of the specificity determinants for Ca2+/phospholipid-dependent protein kinase (protein kinase C) (basic residues both N-terminal and C-terminal to Ser/Thr), we tested calcineurin as a substrate for protein kinase C. Protein kinase C catalyzed rapid stoichiometric phosphorylation, and the characteristics of the reaction were the same as with CaM-kinase II: 1) the phosphorylation was blocked by binding of Ca2+/CaM to calcineurin; 2) phosphorylation partially inactivated calcineurin by increasing the Km (from 9.9 +/- 1.1 to 17.5 +/- 1.1 microM 32P-labeled myosin light chain); and 3) [32P]calcineurin exhibited very slow autodephosphorylation but was rapidly dephosphorylated by protein phosphatase IIA. Tryptic and thermolytic 32P-peptide mapping and sequential phosphoamino acid sequence analysis confirmed that protein kinase C and CaM-kinase II phosphorylated the same site.  相似文献   
135.
At the developmental stage at which the apical hook passed the 3rd and 4th nodes, dark-grown seedlings of pea ( Pisum sativum L. cv. Progress No.9) opened the hook upright and then formed a new hook above the node nearly in the opposite direction to the previous one. In cv. Alaska, in contrast, many (about 84%) seedlings closed the hook in the original direction after they partially (up to about 110°) opened it at the 3rd node, thus doing a wagging movement, while a small percentage (about 16%) of the seedlings reversed the hook direction. Exposure to red light of cv. Alaska seedlings for 10 min increased the percentage of the hook reversion up to 71% or more. The hook reversion was never observed except when the hook part passed the nodes, suggesting the involvement of the nodes in the phenomenon.  相似文献   
136.
Two variants of carrot (Daucus carota L. cv. MS Yonsun) celllines, which had been selected with Al-phosphate as a sole sourceof phosphorous, were characterized on their mechanisms of phosphate-utilizationfrom Al-phosphate. Both cell lines excreted citrate into themedium. The amount of citrate excretion was highly correlatedwith cell growth in the presence of Al-phosphate. There wasabout a 1 to 1 correlation between solublized-Al and excreted-citratein the medium during cell growth. These results suggest that1) the citrate could chelate with Al, at a 1 to 1 ratio, inAl-phosphate, 2) the citrate-chelated Al remains outside thecells, and 3) solublized phosphate from Al-phosphate is utilizedfor the growth of carrot cells. The characteristics of the selectedcells were very stable, since the rate of citrate-excretionshowed no change after subculturing 25 passages without Al-phosphate. (Received August 7, 1989; Accepted October 19, 1989)  相似文献   
137.
138.
When a mixture of bovine brain G-proteins (Gi/o) was loaded onto an octyl sepharose column in the presence of AlF4-, alpha-subunits of molecular weights 39 kDa and the 41 kDa were eluted separately, followed by the appearance of two distinct peaks containing beta gamma-subunits (beta gamma-I, beta gamma-II). Both beta gamma-I and beta gamma-II possessed identical beta-subunits but different gamma-subunits. The molecular weights of the two gamma-subunits determined by SDS-polyacrylamide gel electrophoresis both in the presence and absence of urea were 4.5 kDa (gamma-I) and 5.0 kDa (gamma-II). Tests indicated that the two isolated gamma-subunits are intact and have not undergone proteolysis. The amino acid composition of gamma-I appeared to be distinct from that of gamma-II. Therefore, this method is a simple procedure for isolating beta gamma-I and beta gamma-II.  相似文献   
139.
An intrinsic ATPase inhibitor inhibits the ATP-hydrolyzing activity of mitochondrial F1F0-ATPase and is released from its binding site on the enzyme upon energization of mitochondrial membranes to allow phosphorylation of ADP. The mitochondrial activity to synthesize ATP is not influenced by the absence of the inhibitor protein. The enzyme activity to hydrolyze ATP is induced by dissipation of the membrane potential in the absence of the inhibitor. Thus, the inhibitor is not responsible for oxidative phosphorylation, but acts only to inhibit ATP hydrolysis by F1F0-ATPase upon deenergization of mitochondrial membranes. The inhibitor protein forms a regulatory complex with two stabilizing factors, 9K and 15K proteins, which facilitate the binding of the inhibitor to F1F0-ATPase and stabilize the resultant inactivated enzyme. The 9K protein, having a sequence very similar to the inhibitor, binds directly to F1 in a manner similar to the inhibitor. The 15K protein binds to the F0 part and holds the inhibitor and the 9K protein on F1F0-ATPase even when one of them is detached from the F1 part.  相似文献   
140.
Partial regions of the mRNA encoding a major part of translation elongation factor 1 (EF-1) from a mitochondrion-lacking protozoan,Glugea plecoglossi, that belongs to microsporidians, were amplified by polymerase chain reaction (PCR) and their primary structures were analyzed. The deduced amino acid sequence was highly divergent from typical EF-1's of eukaryotes, although it clearly showed a eukaryotic feature when aligned with homologs of the three primary kingdoms. Maximum likelihood (ML) analyses on the basis of six different stochastic models of amino acid substitutions and a maximum parsimony (MP) analysis consistently suggest that among eukaryotic species being analyzed,G. plecoglossi is likely to represent the earliest offshoot of eukaryotes. Microsporidians might be the extremely ancient eukaryotes which have diverged before an occurrence of mitochondrial symbiosis. Sequence availability: The nucleotide sequence data reported here appear in the GSDB, DDBJ, EMBL, and NCBI databases with the accession number D32139  相似文献   
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