Search PubMed⌕ Search

Biomedical subjects

K Kawada

Publications and source records attributed to K Kawada.

At least 37 records · Page 2Linked to original sources
PubMed1997

Synthesis and evaluation of novel fluorinated methotrexate derivatives for application to rheumatoid arthritis treatment.

An ongoing search for new antifolate drugs useful against rheumatoid arthritis (RA) led us to prepare new methotrexate (MTX) derivatives containing enantiomerically pure L-erythro- or L-threo-gamma-fluoroglutamic acid. The derivatives in which the phenyl ring was replaced by a 3'-substituted phenyl or methylthiophene ring showed potent immunosuppressive activities, including in vitro inhibition of mitogen responses to both T and B cells and in vivo inhibition of antibody production in mice. These compounds also exhibited inhibitory activity in adjuvant arthritis in rats. Their toxicity was lower than that of MTX, which was probably due to the strong electronegativity of fluorine, which increases the acidity of the gamma-carboxyl group and thereby decreases polyglutamylation in normal cells. These results revealed the potential of the fluorinated MTX derivatives as candidate drugs for the treatment of RA.

Animals↗
PubMed1997

Immunoglobulin E production in mice by means of contact sensitization with a simple chemical, hapten.

Production of IgE caused by repeated topical application of 2,4-dinitrofluorobenzene (DNFB) to the ears of BALB/c mice was investigated. Ear thickness increased in proportion to the number of applications. Eczematous changes of the skin included marked infiltration of neutrophils, eosinophils, and monocytes and hypertrophy of the epidermis. Ear thickness due to inflammation reached a maximum 24 hours after the second, third, fourth, and fifth applications. The strong expression of interferon-gamma and IL-2 messenger RNA (mRNA) in the skin lesions indicated the participation of Th1 type helper T cells in the delayed-type hypersensitivity reaction. After the fifth application, the mice showed an immediate cutaneous reaction in addition to the delayed-type hypersensitivity reaction. The immediate reaction appeared within 1 hour of application. Hapten-specific IgE also was detected in serum from the mice, and the expression of germline and productive Cepsilon mRNA was detected in cervical lymph nodes, whereas productive Cepsilon mRNA was detected in the spleen. These results indicate that five topical applications of DNFB to the ear produce local eczematous dermatitis and increase serum hapten-specific IgE level in mice. Eczematous dermatitis is mainly caused by Th1 type T cells, and IgE production is mediated by Th2 type T cells in the cervical lymph nodes. In addition, IgE class switching occurs in the cervical nodes and IgE production occurs in both lymph nodes and spleen.

Animals↗
PubMed1997

FK-506 and cyclosporin A potentiate the IgE antibody production by contact sensitization with hapten in mice.

Five repeated topical applications of 2,4-dinitrofluorobenzene to the ears of BALB/c mice resulted in contact dermatitis on the ears as well as significant elevation in dinitrophenol-specific IgE antibody and total IgE in the serum. FK-506 and cyclosporin A inhibited the development of contact dermatitis in terms of skin thickness and histopathological changes of skin lesions. On the contrary, these two drugs potentiated dinitrophenol-specific and total IgE antibody production without affecting IgG and IgM levels in serum. The expression of interferon-gamma mRNA in reverse transcriptase-polymerase chain reaction in the ear was inhibited by FK-506 and cyclosporin A. The expression of interleukin-4 mRNA, germline C epsilon and productive C epsilon in the auricular lymph node was not affected by these two drugs. Contrary to the above in vivo findings, the immunosuppressors, FK-506 and cyclosporin A, inhibited the production of interferon-gamma and interleukin-2 by cultured Th1 cells (1E10.H2 cells) and of interleukin-4 and -5 by Th2 cells (D10.G4.1 cells) in vitro. These results indicated that FK-506 and cyclosporin A selectively inhibited the Th1 cell-mediated contact dermatitis and potentiated the Th2 cell-mediated IgE antibody production in vivo. This potentiation is probably due to the down-regulation of interferon-gamma production by Th1 cells after the treatment with these drugs. However, because FK-506 and cyclosporin A inhibited the production of cytokines by both Th1 and Th2 cells in vitro and these two immunosuppressors showed higher selectivity toward inhibiting Th1 cell-mediated reactions by limitations in vivo experiments.

Animals↗
PubMed1996

[Investigation for VP4 region of coxsackie virus A16 RNA sequence from hand-foot-mouth disease patients at eastern district of Shizuoka prefecture in 1995].

In 1995 an investigation was made for VP4 regions of coxsackie virus A16 (CA16) RNA sequence from hand-foot-mouth disease patients in eastern district of Shizuoka Prefecture. Subjects were seven patients who were diagnosed as hand-foot-mouth disease due to CA16 at the Ohashi Pediatric Clinic in Susono City. Throat swabs of patients were extracted to RNA. Extracted RNA were assayed by reverse transcription polymerase chain reaction that primers corresponded to VP4 resion of enteroviruses. PCR products were marked by dye-deoxy terminator methods and assayed by direct sequence methods. RNA sequences were classified into two types. Type 1 were three cases, and type 2 were four. The homology was 90.8% between type 1 and type 2. All cases of sixty-nine amino acids were the same as prototype strain. We concluded that the two type strains of CA16 were prevalented in eastern district of Shizuoka Prefecture in 1995. It was at the same time and was widely noted in the eastern district.

Amino Acid Sequence↗
PubMed1996

Effect of KE-298 on experimental arthritis in mice.

KE-298 is a new immunomodulatory agent with a chemical structure similar to that of D-penicillamine. We compared the effects of KE-298 on type II collagen-induced arthritis (CIA) in mice with those of prednisolone. KE-298 at a dose of 25 mg/kg showed only a decrease in the progression of foot pad swelling. At doses of 50 and 100 mg/kg, however, KE-298 inhibited the severity and development of the collagen-induced arthritis index, the progression of foot pad swelling, bone damage and histopathological changes. These inhibitory effects were more pronounced at the dose of 50 mg/kg than at 100 mg/kg. KE-298 also significantly inhibited the delayed-type hypersensitivity (DTH) response to type II collagen, but did not affect the production of anti-type II collagen IgG antibody in arthritic mice. To determine the inhibitory mechanism of KE-298, we studied the effect of KE-298 on IL-1 beta and TNF-alpha production in mice. We found that KE-298 inhibited bacterial lipopolysaccharide (LPS)-induced IL-1 beta production at doses of 50 and 100 mg/kg. It inhibited the production of TNF-alpha at the dose of 50 mg/kg, but not at 100 mg/kg. In summary, at appropriate dosages, KE-298 inhibited CIA and TNF-alpha production in mice. KE-298 also inhibited the DTH reaction to type II collagen and LPS-induced IL-1 beta production in a dose-related fashion. These findings suggest that these effects of KE-298 are closely related to its immunomodulatory action.

Adjuvants, Immunologic↗
PubMed1996

Chemical modification of PA-48153C, a novel immunosuppressant isolated from Streptomyces prunicolor PA-48153.

5beta-Methoxy (20), 14-methyl (24), 14,14-dibromo-15-nor (25), 8-O-acyl (26-45), 8-O-alkyl (46), 8-O-alkoxycarbonyl (47, 48), and 8-O-carbamoyl (49) derivatives of PA-48153C, a novel immunosuppressant isolated from fermentation products of Streptomyces prunicolor PA-48153, were prepared. These compounds were found to retain the inhibitory activity on the responses of both T and B cells to mitogens. Among them, the C-8 hexanoate 28 showed potent suppressive effects on mitogen responses with less cytotoxicity to EL4 cells and was selected for in vivo evaluation.

Animals↗
PubMed1996

[Home care that meets the wishes of patients with terminal stage cancer and their families].

As our ward is a general surgical ward, we formerly had difficulties providing appropriate care for patients with terminal cancer. To solve the problem, we have formed a nursing study group in order to provide home care that would meet the wishes of such patients and their families. Our specific approach was as follows: 1) preparation of a form on which patient information is collected; 2) a support system for home care (such as pain control and home parenteral nutrition; and 3) a solid collaboration system between ward nurses and visiting nurses. Such a program enables us to understand the wishes of patients and families and to provide various support where needed. The project helps to lessen the anxiety and the burden that patients and families feel in home care, and improve the quality of life (QOL).

Aged↗
PubMed1995

Suppressive effects of tranilast on pulmonary fibrosis and activation of alveolar macrophages in mice treated with bleomycin: role of alveolar macrophages in the fibrosis.

We have reported that tranilast, an anti-allergic drug that inhibits chemical mediator release from mast cells, suppresses bleomycin (BLM)-induced pulmonary fibrosis in mice through mechanisms other than inhibiting chemical mediator release from mast cells. The purpose of this paper is to examine the effect of tranilast on alveolar macrophage (AM) activation and on the development of fibrosis in ICR mice instilled with BLM intratracheally. Twenty eight days after the BLM instillation (0.01 mg/mouse), AM often migrated into alveolar spaces surrounding the fibrotic areas. Flow cytometry analysis for the size and density of AM (MAC-1 positive cells) suggested that AM were activated not only in the earlier acute inflammatory phase, but also in the later chronic phase. The p.o. administration of tranilast suppressed an increase of AM activity to produce reactive oxygen species in BLM-instilled mice, and it inhibited the subsequent development of pulmonary fibrosis. In vitro treatment with tranilast suppressed the reactive oxygen species production from murine peritoneal macrophages. However, several different anti-oxidants failed to inhibit the development of fibrosis. These results suggest that the activation of AM plays an important role in the development of fibrosis, and it is likely that tranilast suppresses fibrosis by inhibiting AM activation but not by scavenging reactive oxygen species.

Administration, Oral↗
PubMed1995

[Anesthesia for cesarean section in a patient with intracranial A-V malformation].

We presented a case of intracranial vascular malformations associated with pregnancy. A 32 year-old woman who was at 36 weeks of gestation had been experiencing loss of consciousness and convulsions for 3 years. MRI revealed an intracerebral AVM measuring 3.5 x 3.0cm in the left temporal lobe. Cesarean section was carried out under general anesthesia and epidural anesthesia to prevent the rise of blood pressure and intracranial pressure owing to stress of delivery and labor pain. Intermittent injection of nicardipine was quite effective to control the hypertension during anesthesia.

Adult↗
PubMed1994

Successful treatment of metastatic pulmonary tumors by bronchial arterial infusion chemotherapy in two patients with locally well controlled uterine cancer.

Pulmonary metastatic tumors in two patients with locally well controlled uterine cancer were treated with bronchial arterial infusion chemotherapy. The first patient underwent a radical hysterectomy and pelvic lymphadenectomy for stage IIb cervical cancer. Fifteen months after the operation, pulmonary metastasis was identified. Clinical evidence of tumor was negative after bronchial arterial infusion chemotherapy, systemic chemotherapy and radiotherapy. The patient continues to be healthy without recurrent signs six years after bronchial arterial infusion chemotherapy. The second patient underwent a radical hysterectomy and pelvic lymphadenectomy for stage II endometrial cancer. Fifteen months after the operation, pulmonary metastasis was identified. After bronchial arterial infusion chemotherapy and systemic chemotherapy, regression of the tumors was observed. This patient has also survived for two years since the lung metastases. These results indicate that bronchial arterial infusion chemotherapy is a potent treatment for pulmonary metastases of uterine cancer.

Adult↗
PubMed1994

[Pharmacokinetic and clinical studies on biapenem (L-627) in the pediatric field].

Pharmacokinetic and clinical studies on biapenem (L-627), a newly developed carbapenem, were performed and the following results were obtained. 1. Absorption/excretion: Pharmacokinetics of biapenem was studied in 14 children at doses of 6 mg/kg and 12 mg/kg administered through 30 minutes-drip infusion. Peak plasma levels and plasma half-lives of the 2 doses were 22.5, 29.9 micrograms/ml, and 0.84, 0.85 hours, respectively. Their urinary recovery rates were 54.5 to 76.1% and 37.3 to 59.5%, respectively. Cerebrospinal fluid levels of biapenem in two patients with purulent meningitis were 0.88 and 2.72 micrograms/ml, and the penetration rates were 3.7 to 8.3%. 2. Clinical study: Forty-nine patients were treated with biapenem at doses exceeding 90 to 100 mg/kg/day for purulent meningitis and at doses between 15.0 and 36.0 mg/kg/day for other infections. Biapenem gave "Excellent" or "Good" responses in 48 cases, hence an efficacy rate of 98.0% was obtained. Only one patient with pneumonia showed a fair response. No adverse reactions were observed. Abnormal laboratory test results were noted in 7 patients including elevation of GOT, GPT, and eosinophils. In no cases the treatment had to be discontinued.

Absorption↗
PubMed1993

Synthesis of manool-related labdane diterpenes as platelet aggregation inhibitors.

Enantioselective total synthesis of the labdane diterpene (-)-1, was achieved starting from the R-(-)-enantiomer of the Wieland-Miescher ketone. The enantiomer (+)-1 was obtained by partial synthesis via microbial transformation of sclareol. These results established that the natural compound (+)-1, a platelet aggregation inhibitor, has a normal absolute stereochemistry like that of manool. The B-norlabdane-related compound 44 was also synthesized using a novel ring contraction reaction.

Crystallography, X-Ray↗
PubMed1993

[Synthesis and antibacterial properties of 3-O-alkyl-D-glucose derivatives].

A series of 3-O-alkyl-1,2-O-isopropylidene-alpha-D-glucofuranoses (3-7), 6-deoxy-3-O-dodecyl-6-halo-1,2-O-isopropylidene-alpha-D-glucofuranose s (9-11), and 6-deoxy-3-O-dodecyl-6-halo-D-glucopyranoses (12-14) were prepared from 1,2; 5,6-di-O-isopropyridene-alpha-D-glucofuranose and their antibacterial activities were evaluated. The compounds having C12 and C14 alkylchains at C-3 of 1,2-O-isopropylidene glucoses were the most effective in vitro antibacterial screening, of which the structure-activity relationships are also discussed.

Bacteria↗
PubMed1993

[Synthesis and antimicrobial properties of methyl 3-O-alkyl-glucopyranosides].

A new type of nonionic surface-active agents containing sugars as the hydrophilic group were synthesized and evaluated for their antimicrobial activity. Methyl 6-deoxy-3-O-dodecyl-6-halo-D-glucopyranoside derivatives showed powerful antimicrobial activity, but no significant differences were observed on the activity with regard to the kinds of anomers as well as halogen atoms.

Bacteria↗
PubMed1993

[One-staged operation for funnel chest, mitral regurgitation and annulo-aortic ectasia associated of Marfan's syndrome].

One-staged operation was successfully performed in a 23-year-old female with funnel chest, mitral regurgitation and annulo aortic ectasia secondary to Marfan's syndrome. A midline skin incision was made and the sternum and costal cartilages were mobilized for sternal turnover with rectus muscles pedicle. This procedure offered an excellent operative field, even though the heart and aneurysmal ascending aorta were displaced into the left hemithorax. The combined superior-transseptal approach to the left atrium was used to perform mitral valve replacement. This approach also provided an excellent exposure of the mitral valve. Cabrol's operation was done for annulo aortic ectasia. Our concepts for the operation of open heart surgery complicated with severe funnel chest were discussed.

Adult↗
PubMed1992

[Synthesis and antimicrobial properties of 3-O-alkyl and 3-O-haloalkyl-D-glucoses].

A series of 3-O-alkyl and 3-O-haloalkyl-D-glucoses were prepared from 1,2:5,6-di-O-isopropylidene-alpha-D-glucofuranose and their antibacterial activities were evaluated. The compounds with C12 and C14-alkyl chains were the most effective in vitro antibacterial screening, among 3-O-alkyl and 3-O-haloalkyl derivatives. The 3-O-alkyl derivatives were more effective than 3-O-haloalkyl derivatives.

Bacteria↗