Biomedical subjects

H Mukaiyama

Publications and source records attributed to H Mukaiyama.

14 recordsLinked to original sources

PubMed2001

Discovery of novel N-phenylglycine derivatives as potent and selective beta(3)-adrenoceptor agonists for the treatment of frequent urination and urinary incontinence.

With a novel assay using isolated ferret detrusor to estimate beta(3)-adrenoceptor agonistic activity, we found that a series of glycine derivatives of ritodrine, a beta(2)-adrenoceptor agonist, are potent beta(3)-adrenoceptor agonists, with excellent selectivity versus beta(1) and beta(2) subtypes. Substitution of halogens in the phenyl ring increased potency and selectivity for the beta(3)-adrenoceptor, and this was dependent upon the position of the halogens. The chlorine-substituted derivatives 3f-i exhibited potent beta(3)-adrenoceptor-mediated relaxation of ferret detrusor (EC(50) = 0.93, 11, 14, and 160 nM) and higher potency at beta(3)-adrenoceptors than at beta(1) or beta(2). The intravenous administration of 3h significantly reduced the urinary bladder pressure in anesthetized male rats (ED(50) = 48 microg/kg) without cardiovascular side effects. This article is the first report of structure-activity relationships (SAR) concerning beta(3)-adrenoceptor agonists as agents for the treatment of urinary frequency and incontinence.

Adrenergic beta-Agonists↗

PubMed2001

Beta(3)-adrenoceptor agonists for the treatment of frequent urination and urinary incontinence: 2-[4-(2-[[(1S,2R)-2-hydroxy-2-(4-hydroxyphenyl)-1-methylethyl]amino]ethyl)phenoxy]-2-methylpropionic acid.

In a search for novel analogues of beta(3)-adrenoceptor (AR) agonists relaxing the bladder for treatment of urinary dysfunction, 2-[4-(2-[[(1S,2R)-2-hydroxy-2-(4-hydroxyphenyl)-1-methylethyl]amino]ethyl)phenoxy]-2-methylpropionic acids (1a-e), into which a fibrate-like structure had been incorporated, were synthesised. Compound 1a was found to be a selective beta(3)-AR agonist in functional assays using the ferret detrusor (beta(3)-AR), rat uterus (beta(2)-AR), and rat atrium (beta(1)-AR); beta(3): EC(50)=7.8 nM, beta(2): IC(50)=7,300 nM, beta(1): EC(20)=23,000 nM. The introduction of a chlorine atom or methyl substituent at the ortho-position on the phenyl ring of 1a further improved beta(3)-AR selectivity. In an in vivo study, 1a lowered intrabladder pressure (ED(50)=31 microg/kg) in rats, without increasing heart rate, in keeping with the in vitro results. Consequently, it is proposed that 1a and its analogues (1b-e), possess beta(3)-AR agonistic activity in the absence of undesirable beta(1)- or beta(2)-AR mediated actions, and may be useful for clinical treatment and pharmacological studies.

Adrenergic beta-3 Receptor Agonists↗

PubMed2001

Analysis of alcohol oxidase isozymes in gene-disrupted strains of methylotrophic yeast Pichia methanolica.

A cell-free extract of methanol-grown Pichia methanolica cells was found to contain nine alcohol oxidase (AOD) isozymes by active staining of a native polyacrylamide electrophoresis gel. Our previous study revealed that AOD in P. methanolica was encoded by two genes, MOD1 and MOD2, and the results of an experiment involving Candida boidinii as an expression host suggested that the AOD isozymes observed in P. methanolica were due to random association of Mod1p and Mod2p into an active octamer [Nakagawa et al., Yeast, 15, 1223-1230 (1999)]. This study was conducted using P. methanolica MOD1- and/or MOD2-gene disrupted strains to confirm a previous hypothesis. While the cell-free extract of the wild-type strain gave nine ladder bands, the mod1delta and mod2delta strains gave a single active AOD band corresponding to the mobilities of Mod2p and Mod1p on a native electrophoresis gel, respectively. The cell-free extract of glyceorl-grown wild-type cells gave a single band corresponding to Mod1p, showing that only MOD1 is expressed in glycerol-grown cells. While the expression of both MOD1 and MOD2 was induced by methanol, this finding and our previous observations indicated that the expression of MOD1 and MOD2 was controlled by a distinct regulatory mechanism in P. methanolica.

Journal Article↗

PubMed1999

Alcohol oxidase hybrid oligomers formed in vivo and in vitro.

Cell-free extract prepared from methanol-grown cells of the methylotrophic yeast Pichia methanolica showed nine multiple alcohol oxidase (AOD) bands on active staining in native polyacrylamide gel electrophoresis. Their molecular basis was investigated and two AOD-encoding genes, MOD1 and MOD2, were cloned from P. methanolica genome. When the two genes were expressed in a heterologous host, an alcohol oxidase-depleted strain of Candida boidinii(aod1Delta strain), both MOD1 and MOD2 partially complemented growth defect of the host strain on methanol. While expression of either MOD1 or MOD2 in C. boidinii aod1Delta strain gave a single AOD band corresponding to the band with the largest and smallest mobility among the nine AOD bands, respectively, co-expression of MOD1 and MOD2 resulted in multiple band formation. Mixed oligomerization of Mod1p and Mod2p in vitro also gave nine multiple bands. From these results, we concluded that the nine multiple forms of AOD observed on native-PAGE represent two homo-octamers and seven hetero-octamers of Mod1p and Mod2p. Using this zymogram analysis, we also found that Mod1p was preferably produced at low methanol concentrations in the media, while Mod2p was produced at higher methanol concentrations. This shows distinct regulatory features of the two AOD-encoding genes in this methylotrophic yeast.

Alcohol Oxidoreductases↗

PubMed1989

[Indication of femorotibial and femoroperoneal bypass for Buerger's disease].

Infrapopliteal bypass with autogenous vein graft was performed in twenty-three patients of thromboangiitis obliterans (Buerger's Disease) during the past 8 years. The outflow vessel of the graft had the direct connection with the pedal arch in 3 cases. In 20 cases the graft was anastomosed to the solitary tibial or peroneal segment, in which the occlusive lesion existed between the outflow vessel and pedal arch, or otherwise, the pedal arch was not opacified in the arteriogram. The length of the solitary tibial or peroneal segment of the successful cases ranged from 11.5 cm to 29.0 cm. The cumulative patency rates of the 23 bypass grafts at 3 months, 1 year, 3 years and 5 years were 86.7%, 77.3%, 77.3%, 77.3% respectively. This result is comparable to those of other authors. When the solitary tibial or peroneal artery is found out and is longer than 12 cm in the arteriogram of Buerger's Disease, we are going to perform bypass surgery to the vessel. If the foot is already necrotic, the amputation should be carried out several days or several weeks after the successful reconstructive surgery.

Adult↗

PubMed1988

[A report of an atypical case of Degos' disease with multiple perforations of the stomach and small intestine].

A 47-year old male complaining of severe abdominal pain associated with distention was admitted to our department on August 5, 1986. His first admission to our hospital was 18 days previously for leg pain and fever. He underwent emergency operation with a preoperative diagnosis of acute peritonitis due to perforation of gastric ulcer. Operative findings showed one perforation of the stomach and two of the ileum. Distal gastrectomy, enterectomy and peritoneal drainage were carried out. Resected specimen revealed six ulcers, two of them in the stomach, four in the ileum. Microscopic examination disclosed intimal proliferations of small arteries in the mucosal layer. The vessels near the ulcers were most severely involved but the same changes were also found in the subserous layer and mesentery. It was suggested that the multiple ulcers were secondary to vascular lesions identical to the gastrointestinal lesion of Degos' disease. Postoperative examinations revealed one ulcer in the jejunum and another in the descending colon. Ten months after operation he lives with no complaint on the gastrointestinal tract. Only 80 cases of Degos' disease have been reported in the western countries and 10 cases in Japan. In those atypical cases of Degos' disease without papulosis were only Manuel's and ours.

Humans↗

PubMed1987

Abdominal aortic aneurysm complicated with chronic disseminated intravascular coagulopathy: a case of surgical treatment.

This article reports a case of an infrarenal abdominal aortic aneurysm complicated with chronic disseminated intravascular coagulopathy (DIC). The patient was a 68-year-old man; bleeding of 20 months' duration was reported. Physical examination indicated a pulsating mass in the abdomen. The diagnosis of DIC was made on the basis of standard coagulation studies. Indium 111-labeled platelet scintigraphy demonstrated an increased accumulation of radioactivity over the aneurysm. After preoperative control of the bleeding tendency was obtained by continuous intravenous infusion of gabexate mesilate (FOY), the aneurysm was successfully replaced with a prosthetic graft. Gabexate mesilate therapy is useful for DIC as is heparin therapy. If surgical intervention is required for an abdominal aortic aneurysm with concomitant DIC, preoperative control of bleeding with gabexate mesilate or heparin is recommended to lessen operative bleeding.

Aged↗

PubMed1987

[Three cases of thoracic or thoracoabdominal aortic aneurysm successfully treated with cell saver].

During a three-month period from January to March 1986, reconstructive surgery was performed on three patients with thoracic or thoracoabdominal aortic aneurysm using a temporary bypass procedure. To reduce the amount of blood transfusion required during operation, an autologous blood recovery system, Cell Saver, was used in these three cases. The amount of blood loss, including the blood passing through the Cell Saver, was 7,020g in Case 1, 6,600g in Case 2 and 16,700g in Case 3. The amount of blood transfusion given to these three cases was 1,400g, 4,400g and 6,800g, respectively. The results indicated that the ratio of transfused blood amount to blood loss during operation was successfully reduced to a level of 20-67% of two other cases with thoracoabdominal aortic aneurysm, operated upon without using Cell Saver. Cell Saver was especially effective in Case 3 in which the blood for transfusion was restricted, for it was difficult to collect enough donors to complete operation because of rare blood type of Rh(-) in this case. That is, Cell Saver withdrew 15,000ml of blood through the sucker from the patient and returned it as concentrated and washed RBC during operation.

Aorta, Abdominal↗

PubMed1983