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H Kamei

Publications and source records attributed to H Kamei.

At least 91 records · Page 5Linked to original sources
PubMed1993

Immunohistochemical detection of P-glycoprotein and carcinoembryonic antigen in small cell lung cancer: with reference to predictability of response to chemotherapy.

In an attempt to elucidate the tumor properties relating to responsiveness to chemotherapy, we examined immunohistochemically the expression of P-glycoprotein (P-gp) and carcinoembryonic antigen (CEA) in small cell lung cancer (SCLC) tumors. Tumor specimens from 33 patients were obtained at the time of diagnosis and relapse. Four patients expressed P-gp in their initial tumors, and 7 others did in recurrent tumors. The overall response rate to chemotherapy of the initial tumors was 75% for P-gp-positive initial tumors and 86% for P-gp-negative tumors, whereas the disease-free and overall survival times were significantly shorter in the former than the latter. Three patients showed CEA in their initial tumors, and 5 others did in recurrent tumors. The patients with CEA-positive initial tumors tended to relapse earlier than those with CEA-negative tumors. In addition, recurrent tumors expressing CEA were resistant to salvage chemotherapy. A clear correlation between CEA expression by tumors and the CEA level in the serum was observed at diagnosis as well as at relapse. These findings indicate that P-gp and/or CEA expression by a tumor and elevated CEA level in the serum may predict refractoriness of the tumor to chemotherapy.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1993

Long-term results of combination chemotherapy with or without irradiation in small cell lung cancer: a 5- to 11-year follow-up.

Between April 1981 and December 1987, 148 patients with newly diagnosed small cell lung cancer (SCLC) were treated using combination chemotherapy with or without thoracic irradiation and prophylactic cranial irradiation (PCI) in a series of cooperative therapeutic trials. With a minimum follow-up of 4.7 years, 13 (9%) patients survived and were free of SCLC. These included 11 (15%) of 76 patients with limited disease and two (3%) of 72 patients with extensive disease. Three died without any evidence of SCLC (one each from second leukemia, non-small cell lung cancer, and unrelated disease). The remaining 10 (7%) patients are currently alive and free of SCLC beyond 4.7 years. Since late relapse beyond 5 years is a very rare event, these patients may have been cured. However, late toxicity of PCI must be kept in mind. Three among the 10 patients have suffered from neuropsychologic symptoms of varying degrees in severity. Although the long-term survival rate is a benchmark in the treatment of SCLC, modifications of therapy that may potentially avoid such toxicities should be considered hereafter.

Aged↗
PubMed1993

Synthesis and antifungal activity of pradimicin derivatives. Modifications of the sugar part.

Modifications at the sugar part of pradimicins were carried out by glycosidations of the aglycones or chemical transformations of natural pradimicins and their antifungal activity was evaluated. Among them, some of the D-xylose-modified derivatives (14, 17, 24) showed activity comparable to that of pradimicin A. The structure-activity relationships obtained through there studies clarified the role of the sugar part in the manifestation of antifungal activity: The 5-O-(6-deoxy-beta-D-sugar) is essential for activity and 2'-epi, 3'-oxo and 4'-deoxy sugar derivatives retain activity against yeasts.

Antibiotics, Antineoplastic↗
PubMed1993

Synthesis and antibacterial activity of cephalosporins having a catechol in the C3 side chain.

Cephalosporins having a catechol through a variety of linkages to the C3 position and a different C7 side chain were prepared. Among them, 3-(catechol-4- ylcarbonyloxy)methylcephalosporin (14) and 3-[(E)-3-(catechol-4-ylcarbonyloxy)-1-propen-1-yl]cephalospo rin (10) showed excellent activity against Gram-negative activity including ceftazidime-resistant Escherichia coli, Pseudomonas aeruginosa, Xanthomonas maltophilia and Pseudomonas cepacia.

Cephalosporins↗
PubMed1993

Cephalosporins having a heterocyclic catechol in the C3 side chain. I. Enhancement of efficacy against gram-negative bacteria.

Two groups of cephalosporins substituted with a variety of heterocyclic catechols in the C3 side chain were synthesized. One is a group of 3-(heterocyclic catechol-substituted methyl)cephalosporins and another is 3-[(E)-3-heterocyclic catechol-substituted 1-propen-1-yl]cephalosporins. Cephalosporins in the latter group showed higher in vivo efficacies than those in the former group having the same heterocyclic catechol, especially against Pseudomonas aeruginosa A9843A, although there was no significant difference between their in vitro activity. Among the latter group, the 5,6-dihydroxybenzimidazole derivative (6e) and the 2,6-dihydro-7-hydroxy-6-oxo- isoquinoline derivative (6b) showed much higher activity than ceftazidime (CAZ) and imipenem (IPM) against P. aeruginosa A9843A both in in vitro and in vivo studies.

Animals↗
PubMed1993

Cephalosporins having a heterocyclic catechol in the C3 side chain. II. Improvement of pharmacokinetic profile.

7-[(Z)-2-(2-Aminothiazol-4-yl)-2-methoxy-(or hydroxy)-iminoacetamido]-3- [propen-1-yl]-cephalosporins having a variety of heterocyclic catechol in 3-position of the propenyl group were synthesized. Among them, 6,7-dihydroxyisoquinoline derivatives, 2a and 2b, showed very high and prolonged blood levels after intramuscular administration to mice and higher in vivo antibacterial activity than expected from their in vitro activity. The former cephalosporin (2a) gave well-balanced in vitro and in vivo antibacterial spectra including anti-methicillin-resistant Staphylococcus aureus (MRSA) activity. The latter cephalosporin (2b) also showed good in vitro and in vivo activities against Gram-positive bacteria, especially against S. aureus A15036, a strain of MRSA, the in vivo activity being comparable to vancomycin but was lacking in anti-pseudomonal activity.

Animals↗
PubMed1993

[CAV-PVP chemotherapy and sequential thoracic irradiation (TI) for patients with limited (LD) small cell lung cancer (SCLC)].

In order to assess the effectiveness of sequential TI for the treatment of LD SCLC, we analyzed 69 patients who had received CAV-PVP chemotherapy consisting of cyclophosphamide, adriamycin, vincristine, cisplatin and etoposide, plus sequential TI between 1986 and 1992. TI was delivered at a total dose of 50 Gy, 5 fractions/week for 5 weeks, once patients achieved a maximal response to chemotherapy. Responding patients also received PCI at a total dose of 30 Gy, 5 fractions/week for 3 weeks. Thirty patients achieved CR by chemotherapy and an additional 10 achieved CR after TI, resulting in a CR rate of 58.0%. Of 40 patients achieving CR, 24 have relapsed so far; the primary (in 15) and the brain (in 4) were the major sites of relapse despite TI and PCI. The median survival time was 18.4 months, with a 2-year survival rate of 39% and 3-year survival rate of 20%. Almost all the patients encountered grade 3 or grade 4 leukopenia while receiving chemotherapy, but the toxicity of TI was generally mild. This treatment is useful for patients with LD SCLC.

Adult↗
PubMed1993

[A case of hereditary motor and sensory neuropathy (HMSN type 2) with bilateral recurrent nerve palsy].

An atypical case of hereditary motor and sensory neuropathy (HMSN) type 2 with cerebellar ataxia, hand tremor and bilateral recurrent nerve palsy was described. The patient was a 57-year-old man who complained of dyspnea, stridor , hoarseness during exercise and snored heavily during sleep since he was 20 years old. These symptoms and signs were slowly progressive. He had difficulty in breathing even at resting state when he was 54 years old and since then, he noticed muscle wasting of his hands and feet. Neurological examinations on admission revealed pes cavus, scoliosis, distal muscular atrophy in his four extremities, especially severe in bilateral lower limbs. Deep tendon reflexes were diffusely depressed. The fiberscopic examination demonstrated the limitation of bilateral vocal cord abduction and his tongue was slightly atrophic. Fine postural tremor was found in bilateral hands. Mild limb and truncal ataxias were also noted. Blood pCO2 level was elevated to 66% although FEV1.0% and vital capacity were within normal limits. Peripheral nerve conduction velocities were almost normal, though distal terminal latencies were slightly prolonged and amplitudes of evoked potentials were markedly decreased. The sural nerve biopsy studies revealed the chronic axonal or neuronal degeneration of both large and small myelinated fibers. From the clinical, electrophysiologic and histopathologic findings, the diagnosis of HMSN type 2 with bilateral recurrent nerve palsy and other atypical neurological findings was made. It is practically important to evaluate the presence or absence of vocal cord paralysis in the patients with HMSN from clinical viewpoints.

Biopsy↗
PubMed1993

[Cytotoxic effect of topoisomerase II inhibitors against adriamycin- and etoposide-resistant small cell lung cancer sublines].

Using reverse transcription polymerase chain reaction, we determined mRNA expression of topoisomerase (topo) II alpha and beta in adriamycin- and etoposide-resistant small cell lung cancer sublines, SBC-3/ADM 100 and SBC-3/ETP. The expression of topo II alpha mRNA decreased substantially in SBC-3/ADM 100 and SBC-3/ETP as compared with the parent cell line, SBC-3; 0.71-fold in the former and 0.38-fold in the latter. Similarly, that of topo II beta mRNA decreased to an extent of 0.68-fold in SBC-3/ADM 100 and 0.28-fold in SBC-3/ETP as compared with the parent cell line. SBC-3/ADM 100 and SBC-3/ETP were highly resistant to topo II inhibitors such as daunorubicin, epirubicin, pirarubicin, mitoxantrone, and teniposide. However, SBC-3/ADM 100 showed a less resistance to aclarubicin, and SBC-3/ETP was as sensitive to the drug as was in the parent cell line. The resistance to topo II inhibitors excluding for aclarubicin might be partially explained by the decreased expression of topo II alpha and beta mRNA.

Carcinoma, Small Cell↗
PubMed1992

Preparation and antitumor activity of 2''-O-, 3''-O- and 2'',3''-di-O-substituted derivatives of etoposide.

The 2''-O-, 3''-O- and 2'',3''-di-O-substituted derivatives (4a--p) of etoposide were prepared by nucleophilic substitution of 4'-O-benzyloxycarbonyletoposide (2) followed by deprotection. Controlled reaction (a limited amount of reagents and low temperature) was required for preparing the mono-O-substituted derivatives. In terms of ED125 values, doses which show 125% of T/C against P388 leukemia in mice, both the 2''-O-acetate (4a, ED125 = 0.18 mg/kg) and 3''-O-acetate (4b, 0.23 mg/kg) were nearly as active as etoposide (1, 0.19 mg/kg), while the 2'',3''-di-O-acetate (4c, 1.9 mg/kg) was somewhat less potent. In the replacement with other substituents, antitumor activity of the 2''-O-substituted derivatives was affected much more by the difference of the substituents as compared with that of the corresponding 3''-O-substituted derivatives. In the 2'',3''-di-O-substituted derivatives, the activity was decreased additively on the substituents.

Animals↗
PubMed1992

Protective effect of eurystatins A and B, new prolyl endopeptidase inhibitors, on scopolamine-induced amnesia in rats.

Eurystatins A and B, which are produced by Streptomyces eurythermus R353-21, potently inhibited Flavobacterium prolyl endopeptidase (PED) with IC50 values of 0.004 and 0.002 micrograms/ml, respectively, while no inhibition was observed against another 5 proteases, even at 100 micrograms/ml. The protective effect of eurystatins A and B against scopolamine (3 mg/kg, i.p.)-induced amnesia in rats was evaluated by the step-through one-trial passive avoidance method. When administered i.p. 30 min prior to the acquisition trial, both eurystatins A, at 2-8 mg/kg, and B, at 4-8 mg/kg, significantly protected rats from the amnesic effect of scopolamine without behavioral side effects.

Amino Acid Sequence↗
PubMed1992

Protactin, a new antibiotic metabolite and a possible precursor of the actinomycins.

Streptomyces cucumerosporus strain L703-4 (ATCC 53784) produces a new 4-methyl-3-hydroxyanthraniloylpentapeptide lactone for which we have proposed the name protactin, in addition to several actinomycin components. Protactin is rather resistant to air oxidation but it can be converted to a new actinomycin, actinomycin Zp by ferricyanide oxidation. Actinomycin Zp possesses in vitro antibacterial activity and in vivo antitumor activity against P-388 leukemia in mice.

Amino Acid Sequence↗
PubMed1992

[Treatment of small cell lung cancer in the elderly: the progress and limitation of chemotherapy].

In order to assess the progress and limitation of chemotherapy in the treatment of small cell lung cancer in the elderly, we analyzed 218 patients who had entered into protocol studies between 1982 and 1990. Among those, there were 101 elderly patients (age of greater than or equal to 66 years) and 117 non-elderly patients (age of less than or equal to 65 years). Response to chemotherapy with or without chest irradiation was almost comparable for the elderly and the non-elderly; complete response rate was 52% for limited disease (LD) and 33% for extensive disease (ED) in the elderly, and it was 68% for LD and 23% for ED in the non-elderly. Survival figures of the two groups were quite similar: The median survival time was 12.6 months for the elderly and 14.5 months for the non-elderly, and the 3-year survival rate was 14% for both groups. An improvement of patient survival was observed along with the chronology of the protocols, i.e., with a escalation of dose intensity. Of interest, the improvement was rather evident in the elderly than in the non-elderly. Hematologic toxicity was considerable more frequent and severe in the elderly than in the non-elderly with non-significant statistics. The incidense of fever episodes while neutropenic was significantly more frequent in the elderly. Non-hematologic toxicity was almost comparable for the two groups, with a exception that the elderly showed a trend being predisposed to renal toxicity. In conclusion, such elderly patients as eligible for entry into a protocol study can benefit from intensive treatment as equally as non-elderly patients can.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

[A case of locally advanced esophageal cancer effectively treated with concurrent chemotherapy and radiotherapy].

A case of a 69-year-old man with locally advanced esophageal cancer was reported. The patient received five courses of chemotherapy consisting of cisplatin (30 mg i.v. days 1-5), 5-fluorouracil (500 mg i.v. days 1-5) and bleomycin (5 mg i.m. days 1-5) every four weeks with a split course irradiation at a dose of 50 Gy, which was concurrently given at the second, third and fourth course of the chemotherapy. Treatment was effectively carried out without severe toxicities. The patient achieved a histologically-confirmed complete remission after completion of the treatment. The patient is disease-free and fully active 28 months after the beginning of chemotherapy. The treatment modality appears to be useful for advanced esophageal cancer.

Aged↗