Biomedical subjects

M Okido

Publications and source records attributed to M Okido.

15 recordsLinked to original sources

PubMed2001

Video-assisted parathyroidectomy for primary hyperparathyroidism: a new approach involving a skin-lifting method.

BACKGROUND: Recent advances have allowed the performance of parathyroidectomy as an endoscopic procedure. Carbon dioxide (CO2) insufflation can be used to create a working space in the anterior neck, but it has been associated with a number of complications. We have devised a skin-lifting method to overcome these problems. METHODS: Eleven consecutive patients underwent video-assisted parathyroidectomy. Preoperative imaging revealed a solitary adenoma in all 11 cases. A 3-cm oblique incision was made below the clavicle, and a 5-mm incision was made on the lateral neck. After the skin was lifted, video-assisted parathyroidectomy was performed. RESULTS: Surgery required 186 +/- 50 min. No conversions to conventional cervicotomy were needed. Levels of serum calcium and intact parathormone decreased significantly in all patients on postoperative day 1. Laryngeal recurrent nerve paresis and seroma were noted in one patient each. CONCLUSIONS: Our procedure eliminates any potential CO2 problems and offers the advantages of direct manipulation and improved cosmesis. Endoscopic parathyroidectomy should be considered a viable option for the surgical treatment of a solitary adenoma.

Aged↗

PubMed2001

Infrasternal mediastinoscopic thymectomy in myasthenia gravis: surgical results in 23 patients.

BACKGROUND: Infrasternal mediastinoscopic surgery is a new approach to resection of the anterior mediastinal mass. METHODS: We evaluated this new approach in 23 patients with myasthenia gravis who underwent total thymectomy assisted by infrasternal mediastinoscopy between 1998 and 2000. The results were analyzed with special reference to morbidity and short-term improvement of the disease severity determined according to quantitative myasthenia gravis (QMG) scores. RESULTS: Complete removal of the thymic gland with the pericardial adipose tissue was accomplished through an infrasternal mediastinoscopic approach in 21 of the 23 (91.3%) patients. The remaining 2 patients required conversion to sternotomy, the one for insufficient sternal lifting with vascular tape and the other for invasion of a thymoma to the innominate vein. There was no related mortality and only one complication, a phrenic nerve injury in 1 patient (4.3%). Significant clinical improvement of disease was achieved in the short term and several advantages were apparent. CONCLUSIONS: Infrasternal mediastinoscopic thymectomy is safe and feasible for patients with myasthenia gravis.

Adult↗

PubMed2001

[A case of malignant myoepithelioma in the lacrimal gland].

BACKGROUND: A case of malignant myoepithelioma in the lacrimal gland is reported. CASE: The patient, a 77-year-old male with increasing proptosis in the left eye was referred to us. Steroid therapy was not effective, therefore lateral orbitotomy was performed. RESULT: On pathological examination, the proper structure of actini was normal, but the cord of actini revealed the destruction layer tapering into the surrounding area. The tumor was composed of sarcomatoid changes with spindle-shaped cells, collagen fibers, and myxoid pattern. immunohistochemically, tumor cells were positive for epithelial membrane antigen (EMA) and alpha-smooth muscle actin (alpha-SMA). Electronmicroscopy showed desmosomes in intercellular junctions. CONCLUSION: Recently, there have been attempts to distinguish myoepithelioma from pleomorphic adenoma on the basis of cellular organization. In our case, duct formation was less than in pleomorphic adenoma. Therefore we diagnosed this tumor as malignant myoepithelioma.

Aged↗

PubMed2000

Role of surgery for gallbladder carcinoma with special reference to lymph node metastasis and stage using western and Japanese classification systems.

The role of radical resection in the treatment of gallbladder carcinoma was examined with special reference to lymph node metastasis using two classifications: one proposed by the American Joint Committee on Cancer (AJCC) and the other by the Japanese Society of Biliary Surgery (JSBS). Histologic evaluations for the depth of tumor invasion (T), lymph node metastasis (N), stage, and follow-up for a mean period of 38 months (range 4-185 months) were completed in 52 patients with gallbladder carcinoma who underwent surgical resection from 1982 to 1997. The definition of T was similar in the two classifications. The extent of nodal involvement (N, AJCC; n, JSBS), stage, and survival were examined. In the absence of lymph node metastasis, the 5-year survival rate reached 71%. The 5-year survival rate in patients with involved nodes confined to the hepatoduodenal ligament, posterosuperior pancreaticoduodenal region, or along the common hepatic artery (N1 and part of N2 by AJCC; nl and n2 by JSBS) approximated 28%. In contrast, postoperative survival was poor in the presence of more extensive nodal involvement (rest of N2 by AJCC; n3 and n4 by JSBS), with no 2-year survivors. The definition of stage I was the same in both classifications, and all patients in this stage are alive. The 5-year survival rates in stages II and III by the AJCC were 70.7% and 22.4%, respectively, and those by JSBS 61.9% and 23.1%, respectively. Thus the survival rates in stages I to III were essentially similar irrespective of the staging system. Stage IV showed significantly worse survival than stage III by the JSBS classification. In contrast, the differentiation of stage IV from III by the AJCC was not significant because of the better survival in stage IV that contained any T with nodal involvement in the posterosuperior pancreaticoduodenal region and along the common hepatic artery. Radical resection should be considered for patients with stage I to III disease defined by either classification and applied to the tumor invasion up to T3 with nodal involvement confined to the hepatoduodenal ligament, posterosuperior pancreaticoduodenal region, and along the common hepatic artery. The role of radical surgery seems to be limited in patients with more extensive tumor invasion or lymph node metastasis.

Adult↗

PubMed1996

Influence of phospholipid on bile salt binding to calcium hydroxyapatite and on the poisoning of nascent hydroxyapatite crystals.

Glycine-conjugated, dihydroxy bile salts inhibit calcium hydroxyapatite (HAP) formation by binding to and poisoning nascent crystal embryos. Their taurine-conjugated counterparts bind less well to hydroxyapatite and do not inhibit its formation; but more hydrophobic, synthetic analogs of the taurine conjugated bile salts are inhibitors of hydroxyapatite formation. Because hydrophobicity is an important determinant of the ability of bile salts to inhibit hydroxyapatite crystal growth, experiments were performed to study the effect of the physiologically important mixed micelles of bile salt and phospholipid. Taurodeoxycholate/phosphatidylcholine (10:1) mixed micelles bound to HAP at lower total lipid concentrations than did pure taurodeoxycholate. At low total lipid concentrations, phosphatidylcholine (PC) binding appeared to predominate, suggesting that PC had a higher affinity than did taurodeoxycholate (TDC) for the HAP surface. Although glycodeoxycholate (3 mM) significantly (> 95%) inhibited hydroxyapatite precipitation, higher concentrations of taurodeoxycholate, either alone or mixed with phosphatidylcholine, did not affect hydroxyapatite formation. These results suggest that biliary phospholipids do not modulate the ability of bile salts to inhibit hydroxyapatite crystal growth.

Bile↗

PubMed1994

Inhibition of calcium phosphate precipitation by bile salts: a test of the Ca(2+)-buffering hypothesis.

The ability of bile salts to inhibit the precipitation of either calcium hydroxyapatite or its precursor, amorphous calcium phosphate, by reducing Ca2+ activity or poisoning nascent crystals was determined. When apatite precipitated rapidly (1-4 h), glycocholate and taurine-conjugated bile salts (up to 100 mM) had little effect on apatite formation, but prevented amorphous calcium phosphate precipitation by lowering Ca2+ activity. In contrast, glycodeoxycholate and glycochenodeoxycholate (2-3 mM) inhibited apatite formation for at least 24 h by poisoning embryonic apatite. When apatite precipitated slowly (> 24 h), all the dihydroxy bile salts prevented apatite formation for at least 4 days. At constant initial supersaturation, the phosphate concentration determined the degree of inhibition caused by the six bile salts mixed together in physiologic proportion. At low phosphate concentrations (1.2 mM) total inhibition was achieved by poisoning embryos (approximately -5 mM total bile salt), but with 4.0 mM phosphate only approximately 60% inhibition was attained (150 mM bile salt) by a combination of poisoning and Ca(2+)-buffering. Thus, at low supersaturation all dihydroxy bile salts can prevent apatite formation by reducing free Ca2+ (taurine and glycine conjugates) or poisoning embryos (glycine conjugates). With mixtures of bile salts at higher supersaturation, inhibition of apatite depends on a combination of poisoning and reduction of free Ca2+, mainly caused by glycodeoxycholate and glycochenodeoxycholate.

Bile Acids and Salts↗

PubMed1992

Isolation of a calcium-regulatory protein from black pigment gallstones: similarity with a protein from cholesterol gallstones.

We have previously isolated from 13 cholesterol gallstones a low molecular weight acidic bili-protein that inhibited the precipitation of calcium carbonate in vitro. We now report the isolation of a similar protein from seven black pigment gallstones. Cholesterol was removed from the stones by Soxhlet apparatus with methyl t-butyl ether, and bile acids were extracted with methanol. The protein was purified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis after demineralization of the stones with ethylenediaminetetraacetate. Structural and functional properties of the protein from the black stones that were similar to the protein from the cholesterol stones included the following: (a) an apparent molecular weight of about 5 kD; (b) a high content of acidic (19.8%) and hydrophobic (50.1%) amino acids with a low content of basic residues (8.4%) and little sulfide-containing amino acids (1.9%); (c) an inhibitory effect on both the initiation and growth of calcium carbonate crystals in vitro; and (d) very tight (possibly covalent) binding of a diazo-positive yellow pigment, presumably bilirubin, with maximum spectral absorbance at 410 nm. The structural and functional similarities of these bili-proteins from black pigment and cholesterol gallstones and their striking effects on calcium carbonate precipitation in vitro suggest that they play a common role in the regulation of precipitation of calcium salts during the formation of both types of gallstones.

Calcium Carbonate↗

PubMed1983

Changes of serum total cholesterol and triglyceride levels in normal subjects in Japan in the past twenty years. Research committee on familial hyperlipidemia in Japan.

Serum lipid levels of 10,977 normal Japanese subjects in 1980 were determined by a joint study of 14 institutions, specializing in lipid research, located in 9 districts of Japan. The data obtained were compared with those in 1960 and 1970. Total cholesterol (TC) levels in 1980 increased with age except for the 1st decade and reached maximum (205 mg/dl) at the 7th decade. The mean value in any age was higher than that of 20 years ago by 10-15 mg/dl. Triglyceride (TG) levels also increased with age and reached maximum (130 mg/dl) at the 7th decade. The mean values of subjects over the 5th decade were higher than those of 10 years ago by 10-20 mg/dl. In contrast with TC and TG, HDL-cholesterol levels were highest at the 1st decade and declined gradually with age. TC and TG levels of younger age (1st to 3rd decade) were equal to or even higher than those of Americans in 1972-76. It was concluded that serum lipid levels of Japanese have increased in the past 20 years and approached to the levels of Europeans and Americans.

Adolescent↗

PubMed1974