[Effect of clarithromycin on prolonging the life expectancy of patients with primary lung cancer].
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to K Hamada.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The effects of NS-49 ((R)-(-)-3'-(2-amino-1-hydroxyethyl)-4'-fluoromethane sulfonanilide hydrochloride), an alpha 1A-adrenoceptor-selective agonist, on intraurethral pressure and blood pressure were investigated in anesthetized dogs. In addition, the contractile effects of NS-49 on the isolated dog urethra and carotid artery were compared with those of non-selective alpha 1-adrenoceptor agonists. Intravenously (i.v.) administered NS-49 at 0.3 microgram/kg or more significantly increased intraurethral pressure in a dose-dependent manner. Much higher doses of NS-49 were needed to increase blood pressure. In contrast, ST-1059 (1-(2',5'-dimethoxyphenyl)-2-aminoethanol) (an active metabolite of midodrine) at 30 micrograms/kg or more significantly increased both intraurethral pressure and blood pressure. NS-49 was 11-fold more selective for intraurethral pressure than ST-1059, NS-49, ST-1059, phenylephrine and noradrenaline caused concentration-dependent contraction of the isolated dog urethra. NS-49 caused only a slight contraction of the dog carotid artery even at high concentrations, whereas the reference drugs caused contractions of the artery with high efficacy. The alpha 1A-adrenoceptor-selective antagonists 5-methyl-urapidil and WB-4101 also showed high affinity for alpha 1-adrenoceptors in the dog urethra in inhibiting [3H]prazosin binding. In conclusion, the alpha 1A-selective agonist NS-49 selectively increased intraurethral pressure in dogs, and produced selective contraction of the dog urethra. These results suggest that the alpha 1A-adrenoceptor subtype is responsible for the contraction of the urethra and the regulation of intraurethral pressure, and that NS-49 might be useful for the treatment of stress incontinence with little effect on the cardiovascular system.
The effects of thyrotropin-releasing hormone (TRH) and its new analog, NS-3 (montireline), on the lower urinary tract in rabbits were investigated. TRH and NS-3 elicited transient increases in intravesical pressure and micturition. They also caused long-lasting increases in intraurethral pressure and EMG activity of the external urethral sphincter, which were not affected by prazosin or transection of the hypogastric nerve, but were eliminated by transection of the pudendal nerve. In animals decerebrated at the supracollicular post-mammillary level, these drugs did not increase intravesical pressure or micturition, but they did elicit increases in intraurethral pressure and sphincter EMG activity. No binding sites for TRH were found in the lower urinary tract. These findings suggest that the sites of action of TRH and NS-3 which elicit intravesical pressure increase or micturition might be located in the area rostral to the pons, and that the sites of action which elicit increases in intraurethral pressure and sphincter EMG activity might be located caudal to the rostral pons.
Two proteins play important roles in the expression of vitamin D function: the specific nuclear receptor protein (vitamin D receptor, VDR) and the transport protein (vitamin D binding protein, DBP). This study was conducted to clarify the conformation of vitamin D responsible for binding to those proteins. For the purpose, the side chain mobility of 1,25(OH)2D3 (1) and its 20-epimer, 20-epi-1,25(OH)2D3 (2), was analyzed by a systematic conformational search. The results were depicted as a three-dimensional dot map, which indicates that the side chains of the two vitamins (1 and 2) occupy different spatial regions that are separated in two areas. We denoted these areas as A and G for 1 and EA and EG for 2. Four analogs, the diastereomers at C(20) and C(22) (3-6) of 22-methylated 1,25(OH)2D3 whose side chains were confined to occupy G, A, EA, and EG, respectively, were designed. These analogs (3-6) were synthesized efficiently by a stereoselective conjugate addition of organocuprate to steroidal E- and Z-22-en-24-ones as the key step. In binding to the VDR the affinities of the analogs (3-6) relative to 1,25-(OH)2D3 (1) were 1/60, 1/3, 20, and 1/100, respectively. These results indicate that the A region is responsible for binding of 1 to VDR and the EA region for binding of 2. Only isomer 4 showed significant affinity for DBP, indicating only the A region is responsible for binding to DBP. Thus, 5 showed clear separation of binding affinities for two proteins, VDR and DBP. Having the highest known VDR affinity, (22R)-22-methyl-20-epi-1,25(OH)2D3 (5) has potential both as a therapeutic agent and as a tool to study the molecular mechanism of vitamin D-mediated gene transcription.
In most cervical cancers, the function of p53 is down regulated. To explore the potential use of p53 in gene therapy for cervical cancer, we introduced wild-type p53 into cervical cancer cell lines via a recombinant adenoviral vector, Ad5CMV-p53, and analyzed its effects on cell and tumor growth. The transduction efficiencies of all cell lines were 100% at a multiplicity of infection of 100 or greater. The p53 protein was detected in Ad5CMV-p53-infected cells. Protein expression peaked at day 3 after infection and lasted 15 days. The Ad5CMV-p53-infected cells underwent apoptosis, and cell growth was greatly suppressed. The Ad5CMV-p53 treatment significantly reduced the volumes of established s.c. tumors in vivo. These results indicate that transfection of cervical cancer cells with the wild-type p53 gene via Ad5CMV-p53 is a potential novel approach to the therapy of cervical cancer.
BACKGROUND: Tissue factor (TF), a cell surface receptor of factor VII/VIIa, was initially recognized as an initiator of the extrinsic coagulation pathway. TF has recently been found to be expressed highly in certain types of malignant tumors. In addition, TF belongs to the interferon receptor family and is one of the immediate early genes, suggesting that TF may participate in the regulation of cell growth. However, the correlation between the expression of TF and cell growth is still unclear. METHODS: Expression of TF in 6 glioma cell lines and 44 glioma surgical specimens was studied by Northern blot analysis, Western blot analysis, immunohistochemistry, and in situ hybridization. RESULTS: Northern blot analysis showed that glioma cells expressed minor novel transcripts of 3.3 kb and 1.6 kb, in addition to the transcripts of 2.2 kb and 3.1 kb that were previously reported. Western blot analysis revealed that the level of TF protein did not correlate with that of TF transcripts. Although immunohistochemical analysis of surgical specimens showed that all gliomas were positive for TF, it was interesting that 1 of 10 benign gliomas (10%) was positive for TF (malignancy Grade I-II), 13 of 14 anaplastic astrocytomas (86%) (malignancy grade III) and 19 of 20 glioblastomas (95%) (malignancy grade IV) were moderately or strongly positive for TF. In situ hybridization showed the expression of TF mRNA in glioma cells. CONCLUSIONS: TF is expressed in glioma and the level of expression correlates with the histologic grade of malignancy.
A novel method for high-efficiency and region- controlled in vivo gene transfer was developed by combining in vivo electroporation and intraarterial plasmid DNA injection. A mammalian expression plasmid for the Escherichia coli lacZ gene (driven with a SV40 early promoter) was injected into the internal carotid artery of rats whose brain tumors (from prior inoculation) had been electroporated between two electrodes. The lacZ gene was efficiently transferred and expressed in the tumor cell 3 days after plasmid injection. However, neither any gene transfers nor any elevated lacZ activity was detected in tissues outside the electrodes. The plasmid was not transferred without electroporation. Human monocyte chemoattractant protein-1 cDNA was also transferred by this method, and its long-lasting (3 weeks) expression was confirmed by using the Epstein-Barr virus episomal replicon system. The expressed monocyte chemoattractant protein-1 protein was functional, as evident by the presence of a large number of monocytes in tumor tissue. This method, electrogene therapy, which does not require viral genes or particles, allows genes to be transferred and expressed in desired organs or tissues, and it may lead to the development of a new type of highly effective gene therapy.
We have investigated how point mutations in the two ATP-binding motifs (G(463)PNGCGK(469)ST and G(701)PNGAGK(707)ST) of elongation factor 3 (EF-3) affect ribosome-activated ATPase activity of EF-3, polyphenylalanine synthesis, and growth of Saccharomyces cerevisiae. The point mutation impaired the ribosome-activated ATPase activity of EF-3, when glycine(463 and 701) and lysine(469 and 707) were replaced with valine and arginine, respectively. Thus, each glycine and lysine residue in both ATP-binding motifs is indispensable for EF-3's binding with ATP and the ensuing generation of ribosome-activated ATPase activity. Additionally, the mutant EF-3s did not catalyze polyphenylalanine synthesis in vitro when each glycine(463 and 701) was replaced with valine. The mutant EF-3s did not support cell growth in TEF3-disrupted S. cerevisiae, when each lysine(469 and 707) and glycine(463) was replaced with arginine and valine, respectively. Thus, each of the two ATP-binding motifs of EF-3 is indispensable for the ribosome-activated ATPase activity of EF-3, which is required for protein synthesis and cell growth in S. cerevisiae.
Serum stimulation of human diploid fibroblast IMR-90 cells leads to phosphorylation of p33CDK2 at Thr160 and activation of CDK2 kinase, a necessary event for G1/S transition. We report that serum stimulation causes a gradual, sustained increase in the activity of CDK-activating kinase (CAK) that phosphorylates CDK2 at Thr160, which starts by 5 h after serum stimulation and reaches the maximal plateau level at around the G1/S boundary. In this cell type addition of phorbol-12, 13-dibutyrate 5 h but not 16 h after serum stimulation completely inhibits CDK2 kinase activation and DNA synthesis. Phorbol ester treatment does not reduce the protein level of p33CDK2, but does inhibit serum-stimulated increases in the CAK activity and CDK2 phosphorylation at Thr160. The suppression of the CAK activity by the phorbol ester is accompanied by decreases in the message levels of both CDK7 and cyclin H, the catalytic and the positive regulatory subunit of CAK, respectively. These results indicate that in IMR-90 cells activation of protein kinase C in the late G1 phase causes cell cycle arrest before the G1/S boundary at least in part through downregulation of CAK and CAK-mediated CDK2 phosphorylation and activation.
Human papillomavirus (HPV) has been identified in the majority of invasive cancers of the uterine cervix sampled and has been found to contribute in a significant way to the genesis of human cervical cancer. HPV has two transforming genes that encode the oncoproteins E6 and E7. E6 can form complexes with p53 and promote p53 degradation. We introduced wild-type p53 into a cervical cancer cell line via a recombinant adenoviral vector, Ad5CMV-p53. Human cervical cancer cell line HeLa, which has HPV type 18 and wild-type p53, was used in this study. Cells were grown in RPMI medium supplemented with 10% heat-inactivated fetal bovine serum. Ad5CMV-p53 was created by inserting the cytomegalovirus promoter, wild-type p53 cDNA, and SV40 polyadenylation signal in a minigene cassette into the E1-deleted region of the modified Ad5 adenovirus. The transduction efficiency was 100% when a dose ensuring a multiplicity of infection of 100 or greater was used. The p53 protein was detected in Ad5CMV-p53-infected cells by immunohistochemical and Western blot analyses. The growth of the Ad5CMV-p53-infected cells was greatly suppressed as detected by both cell count and [3H]thymidine incorporation assay. These data suggest that transfection of HPV-positive cervical cancer cells with a wild-type p53 gene in a form such as Ad5CMV-p53 is a potential novel therapy for cervical cancer.
To explore the potential of an adenoviral antisense RNA transcript for gene therapy of cervical cancer, we introduced the antisense RNA transcript of E6 and E7 genes of human papillomavirus (HPV) 16 into cervical cancer cells harboring HPV 16 via a recombinant adenoviral vector, Ad5CMV-HPV 16 AS and analyzed the effects of expression of these genes on cell growth and tumor growth. Ad5CMV-HPV 16 AS contains the cytomegalovirus-promoter, E6 and E7 genes of HPV 16 in antisense orientation, and the SV40 polyadenylation signal in a mini-gene cassette, which is inserted into the E1-deleted region of modified adenovirus 5. The entire E6/E7 region of HPV 16 was amplified by polymerase chain reaction (PCR) before cloning into the mini-gene cassette. By reverse transcriptase-PCR, HPV 16 E6/E7 antisense RNA was detected in SiHa cells infected with Ad5CMV-HPV 16 AS. The growth of the Ad5CMV-HPV 16 AS-infected cells was greatly suppressed, as evidenced by a decrease in cell count. The growth inhibitory effect of Ad5CMV-HPV 16 AS was significantly enhanced by an adenoviral p53 construct, Ad5CMV-p53. In an ex vivo study in nude mice, tumorigenicity was completely inhibited in mice injected with Ad5CMV-HPV 16 AS-infected SiHa cells. These data suggest that transfection of cervical cancer cells with HPV 16 E6/E7 antisense RNA in a form such as Ad5CMV-HPV 16 AS is a potential novel approach to the therapy of HPV 16-positive cervical cancer.
Although 2', 5'-oligoadenylate synthetase (2-5AS) is an enzyme induced by inferferon (IFN) or viral infections and mediates one of the principal antiviral pathways turned on by IFN, low constitutive levels of the enzyme can be detected in various "normal" animals that have not been treated with IFN or virus. The distribution of this enzyme in the female and male reproductive organs of normal healthy mice was studied by Western blotting and by an immunohistochemical method, using a specific monoclonal antibody. On Western blotting, an antibody to 42-kD 2-5AS reacted with extracts from the ovary, oviduct, uterus, vagina, and placenta among the female reproductive organs, and testis, epididymis, and ductus deferens in the male. Immunohistochemically, the 2-5AS was localized on the following cells in the female reproductive organs: oocytes in the ovary; epithelium in the oviduct, uterus, and vagina; and trophoblasts in the placenta. Furthermore, the 2-5AS was localized on the epithelium and muscular layer in the ductus deferens and epithelium in the penis of the male mice, whereas the epithelium of the testis, epididymis, and seminal vesicle were stained faintly. It is well known that IFN is produced continuously in normal mice, so the 2-5AS in the tissues of normal mice is considered to be induced by such IFN produced under physiological conditions. Expression of the 2-5AS on the epithelium and trophoblasts in the reproductive organs may be responsible for the prevention of viral infections. However, the enzyme in oocytes may have some functions other than as an antiviral agent, since the enzyme was not detectable in embryos during early development.
This review is based on 66 patients with partial-thickness tears of the rotator cuff, verified at operation. Their average age was 54 years, and all had symptoms of subacromial impingement. The duration of shoulder pain was for between 2 and 108 months (mean 11.4 months). Ultrasonography, arthrography and bursography were helpful in establishing the diagnosis. On exploration, tears were found in the supraspinatus tendon, with 9 extending into the infraspinatus. After anterior acromioplasty, excision of the diseased portion and tenorrhaphy were undertaken. Satisfactory results were obtained in 62 patients (94%) with an average follow-up of 32 months. Spontaneous repair at the torn site was never seen. In addition to Neer's staging of impingement, we propose a new classification based on the integrity of the cuff tendon. We conclude that a partial-thickness cuff tear is an important cause of shoulder disability, which deserves much more clinical attention; misdiagnosis is common and leads to mismanagement. When conservative treatment fails, accurate diagnosis and proper surgical repair are essential.
OBJECTIVES: More than 90% of cervical cancers are positive for human papillomavirus, which functionally represses p53 and pRb. The remainder have been found to contain p53 mutations. Gene therapy involves insertion of a functioning gene into a patient to correct a genetic abnormality. STUDY DESIGN: The ability of a beta-galactosidase adenovirus to mediate transgene expression in the rhesus cervix was evaluated. Three different doses and two different entry techniques of virus were investigated. RESULTS: The ideal dose determined by X-galactosidase staining was 2 x 10(10) plaque-forming units, and the injection method yielded better staining than did abrasion with topical application. Increased adenoviral-specific immunoglobulin G antibody response in the injected monkeys confirmed the results. CONCLUSION: High transduction efficiency by use of adenoviral vectors can be achieved in the cervix. Reversing the effects of human papillomavirus and p53 mutations with gene therapy may become a novel therapy for invasive and preinvasive cervical cancer.
The gene for SCA2 has been mapped to chromosome 12q23-q24.1, but the mutant gene remained to be identified. When studying a Japanese family with SCA2, we noted that clinical features and disability varied among patients, with the central feature being progressive ataxia-slow eye movement-hyporeflexia syndrome. Additional symptoms were parkinsonism with minor cerebellar deficits, and severe ataxia with choreoathetosis. Our experience plus related literature documentation indicates that choreoathetosis is not so rare at the advanced stage of the disease, with onset at an early age, and that the variety of SCA2 phenotype depends on age at onset and duration of the disorder.
We examined the binding of various steroid hormones to DNA in vitro by means of 32P-postlabeling. Seventeen steroid hormones and cholesterol (CS) were incubated with human liver DNA at 37 degrees C for 1 h under aerobic conditions in the absence of catalysis. The reaction mixtures were analyzed by the nuclease P-1 version of 32P-postlabeling. The results showed that cortexolone (CX), prednisolone (PS), cortisone (CN), cortisol (CL), tetrahydrocortisol (TC), corticosterone (CC), 11-deoxycorticosterone (DC), dexamethasone (DX), dihydrocortisol (DL), and aldosterone (AL) covalently bound with DNA. However, progesterone (PG), 17 alpha-hydroxyprogesterone (HG), estrone (E1), estradiol (E2), estriol (E3), testosterone (TS), cortol (CR) and the original compound for biosynthesis, CS, did not form adducts. In absence of DNA, the steroids themselves did not give rise to any spot on TLC under the same conditions. The dose-responses of DNA binding by DC, DL, CC, CL and CN were linear. The relative adduct labeling of reactive steroids at a concentration of 2 mM were as follows: 68.8 (CX), 53.2 (PS), 39.6 (CN), 29.9 (CL), 20.9 (TC), 12.9 (CC), 12.3 (DC), 7.5 (DX), 4.7 (DL), 1.2 (AL) adducts per 10(8) nucleotides. Reactive and nonreactive steroids were distinguishable by the presence or absence of the carbonyl group (-CO-CH2OH) at carbon seventeen (C17) of the cholesterol skeleton. This implies that the electrophilic carbonyl or a neighboring group perhaps involved in the formation of covalent bond with DNA. To investigate the nature of target base(s) of these DNA reactive steroids, mononucleotides of all four bases of DNA were reacted with CN, CL, CC and cochromatographed with the obtained spots of DNA reactions. The results of which stated that these steroids and guanine reaction gave the same spots as observed in DNA reaction, indicating guanine is the main target of these DNA reactive steroids. Hep G2 human hepatocellular carcinoma cells were used as an alternative model. Although nine steroids (CL, DL, TC, PS, DX, PG, E2, TX, CR) did not react with intracellular DNA under our experimental conditions, our findings suggested that some hormonal steroids can form covalent DNA adducts in vivo.
We examined changes in the hypervariable region 1 of the hepatitis C virus (HCV) RNA that occurred with interferon therapy in 33 patients with chronic hepatitis C to assess the clinical significance of this region. The 33 patients had HCV genotype 1b and were classified into three groups based on serum aminotransferase levels during and after therapy with alpha interferon; long-term responders (n = 9), short-term responders (n = 11), and nonresponders (n = 13). Changes in the genetic heterogeneity of the hypervariable region 1 were determined by using nonisotopic polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). HCV RNA levels were evaluated by reverse transcriptase PCR and branched DNA probe assays. Changes in sequences were determined by cloning and sequencing analysis. Before therapy, the long-term responders had significantly lower degrees of heterogeneity and lower viral levels than nonresponders. There were no significant differences between short-term and nonresponders. With interferon therapy, viral levels and degree of heterogeneity decreased to a greater extent among long-term and short-term responders than among nonresponders. Sequencing analysis showed that the three groups had similar clone numbers initially, but long-term responders had rather homogeneous viral populations, whereas short-term and nonresponders had heterogeneous populations, but that there were no nucleotide sequences or amino acid alignments that were specific for any group before, during, and 6 months after therapy. Approximately half of short-term and nonresponders received a second course of interferon 7 to 10 months after the initial therapy; all showed an identical response to the second course of therapy regardless of interim changes in the heterogeneity of hypervariable region 1. These findings suggest that (1) patients who were nonresponders or short-term responders had mixed viral populations that had differing sensitivities to interferon, (2) the changes in the hypervariable region 1 (HVR 1) did not affect responsiveness to interferon, and (3) the lower heterogeneity in the HVR 1 was associated with a long-term response to interferon only when the viral levels were low.