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Biomedical subjects

T Komaki

Publications and source records attributed to T Komaki.

At least 19 recordsLinked to original sources
PubMed2001

Production of beta-mannanase and beta-mannosidase from Aspergillus awamori K4 and their properties.

beta-Mannanase and beta-mannosidase from Aspergillus awamori K4 was produced by solid culture with coffee waste and wheat bran. The optimum composition for enzyme production was 40% coffee waste-60% wheat bran. Two enzymes were partially purified. Optimum pH was about 5 for both enzymes, and optimum temperature was around 80 degrees C for beta-mannanase and 60-70 degrees C for beta-mannosidase. These enzymes produced some oligosaccharides from glucomannan and galactomannan by their hydrolyzing and transferring activities. beta-Mannanase hydrolyzed konjak and locust bean gum 39.1% and 15.8%, respectively. Oligosaccharides of various molecular size were released from glucomannan of konjak, but on the addition of cellulase, mannobiose was released selectively. In locust bean gum, tetra-, tri-, and disaccharides (mannobiose) were mainly released by K4 beta-mannanase. Tetra- and trisaccharides were heterooligosaccharides consisting of galactose and mannose residues. K4 beta-mannosidase had a transglycosylation action, transferring mannose residue to alcohols and sugars like fructose.

Aspergillus↗
PubMed2001

Usefulness of thyrotropin (TSH)-releasing hormone test and nocturnal surge of TSH for diagnosis of isolated deficit of TSH secretion.

Six patients with idiopathic isolated deficit of TSH secretion were examined and reported on. Their clinical symptoms and routine biochemical data were unclear and were not specific for hypothyroidism. Serum triiodothyronine, free thyroxine and TSH levels were slightly low or low-normal. Basal metabolic rate and thyroidal (123)I-uptake were also slightly low or low-normal. The response of serum TSH to TRH stimulation was blunted in all patients. No nocturnal surge of serum TSH level could be seen in any of the patients. Empty sella was revealed in three patients, and pituitary microadenoma in one patient via magnetic resolution imaging. Antihuman pituitary cytosol antibody was seen in five patients. Autoimmunity may have played a role in the pathogenesis of idiopathic isolated TSH deficiency. Routine examination of thyroid function cannot easily detect this disease. TSH response to TRH stimulation and nocturnal surge of TSH should be examined when this disease is suspected.

Adult↗
PubMed2001

Pretreatment with ammonia water for enzymatic hydrolysis of corn husk, bagasse, and switchgrass.

Bagasse, corn husk, and switchgrass were pretreated with ammonia water to enhance enzymatic hydrolysis. The sample (2 g) was mixed with 1-6 mL ammonia water (25-28% ammonia) and autoclaved at 120 degreesC for 20 min. After treatment, the product was vacuum-dried to remove ammonia gas. The dried solid could be used immediately in the enzymatic hydrolysis without washing. The enzymatic hydrolysis was effectively improved with more than 0.5 and 1 mL ammonia water/g for corn husk and bagasse, respectively. In bagasse, glucose, xylose, and xylobiose were the main products. The adsorption of CMCase and xylanase was related to the initial rate of enzymatic hydrolysis. In corn husks, arabinoxylan extracted by pretreatment was substantially unhydrolyzed because of the high ratio of arabinose to xylose (0.6). The carbohydrate yields from cellulose and hemicellulose were 72.9% and 82.4% in bagasse, and 86.2% and 91.9% in corn husk, respectively. The ammonia/water pretreatment also benefited from switchgrass (Miscanthus sinensis and Solidago altissima L.) hydrolysis.

Adsorption↗
PubMed2001

Hypervascular liver metastasis from hypovascular ductal cell carcinoma of the pancreas.

In a case of hypervascular metastatic liver tumor, the vascularity of primary focus, pancreatic carcinoma was hypovascular. Based on the imaging findings, we thought before the operation that the two lesions were double cancers. Histological examination showed that the stromal volume of metastatic tumorous tissue was richer than that of the primary focus. It was suggested that the difference in the stromal volume was related to the difference of the vascularity. Some foctors originating in stromal cells might be involved in angiogenesis.

Carcinoma, Pancreatic Ductal↗
PubMed2000

Properties of chitosanase from Bacillus cereus S1.

Chitosanase from Bacillus cereus S1 was purified, and the enzymatic properties were investigated. The molecular weight was estimated to 45,000 on SDS-PAGE. Optimum pH was about 6, and stable pH in the incubation at 40 degrees C for 60 min was 6-11. This chitosanase was stable in alkaline side. Optimum temperature was around 60 degrees C, and enzyme activity was relatively stable below 60 degrees C. The degradations of colloidal chitosan and carboxymethyl cellulose (CMC) were about 30 and 20% relative to the value of soluble chitosan, respectively, but colloidal chitin and crystalline cellulose were not almost hydrolyzed. On the other hand, S1 chitosanase adsorbed on colloidal chitin completely and by about 50% also on crystalline cellulose, in contrast to colloidal chitosan, which it did not adsorb. S1 chitosanase finally hydrolyzed 100% N-deacetylated chitosan (soluble state) to chitobiose (27.2%), chitotriose (40.6%), and chitotetraose (32.2%). In the hydrolysis of various chitooligosaccharides, chitobiose and chitotriose were not hydrolyzed, and chitotetraose was hydrolyzed to chitobiose. Chitobiose and chitotriose were released from chitopentaose and chitohexaose. From this specificity, it was hypothesized that the active site of S1 chitosanase recognized more than two glucosamine residues posited in both sides against splitting point for glucosamine polymer.

Adsorption↗
PubMed2000

Undefined complications of parathyroid adenoma, parathyroid hyperplasia (primary hyperparathyroidism), thyroid follicular adenoma, thyroid papillary carcinoma, temporal astrocytoma, cerebellar meningioma, and hemangioma of external auditory meatus and oral papilloma.

A 59-year-old woman who had parathyroid adenoma, parathyroid hyperplasia, thyroid follicular adenoma, thyroid papillary carcinoma, astrocytoma of the right temporal lobe, cerebellar meningioma, capillary hemangioma of the left external auditory meatus and papilloma of the left upper gingiva is reported. Dynamic magnetic resonance imaging, computed tomography with contrast-enhancement and gastrofiberscopy revealed no remarkable findings in the pituitary, pancreas, adrenals, stomach or duodenum. Similar lesions were not found in any family members. Defect of the causative genes of multiple endocrine neoplasia types I and IIa, MENIN and RET was not detected. Further follow-up of this patient and family members is needed.

Adenoma↗
PubMed1999

Reduction of plasma gonadotropin levels and pituitary tumor size by treatment with bromocriptine in a patient with gonadotropinoma.

A pituitary tumor with suprasellar extension was found by magnetic resonance imaging (MRI) in a male with diabetes mellitus. Endocrine examination revealed high plasma follicle-stimulating hormone (FSH) and alpha-subunit levels, which increased with administration of thyrotropin (TSH)-releasing hormone (TRH). Plasma luteinizing hormone (LH) and testosterone levels were low. Pituitary gonadotropin producing tumor was diagnosed. Because the patient refused surgery, bromocriptine was administered and plasma FSH and alpha-subunit rapidly decreased; on MRI the tumor size was gradually reduced. When pituitary operation is not feasible, bromocriptine is one choice of treatment.

Adenoma↗
PubMed1998

Extrahepatic biliary cystadenocarcinoma arising from the left hepatic duct.

A 54-year-old man, who had no clinical symptoms, underwent a routine health checkup at our hospital. Abdominal ultrasonography disclosed a well demarcated tumor containing a solid portion occupying the dilated left hepatic duct and a cystic portion expanding into the parenchyma of the left hepatic lobe, with mild dilatation of the intrahepatic bile ducts. These findings were later confirmed by computed tomography (CT) and magnetic resonance imaging. Endoscopic retrograde cholangiography revealed a complete defect at the level of the left hepatic duct, while drip infusion cholangiographic-CT (DIC-CT) disclosed a defect of the left hepatic duct only, with the distal portions of the left intrahepatic ducts being visualized on the image. Hepatic angiography revealed light stains in the solid portion in the parenchymal phase. At left lobectomy, a multiloculated polyp-like tumor was found arising from the left hepatic duct and expanding into the parenchyma of the left hepatic lobe. Microscopically, all the lining cells in the cysts and the tumor cells in the solid portion showed the features of papillary adenocarcinoma. In this patient with extrahepatic biliary cystadenocarcinoma, DIC-CT was useful in identifying the site of origin of the tumor, and hepatic angiography was also useful in differentiating this rare malignant tumor from benign cystadenoma.

Bile Duct Neoplasms↗
PubMed1997

Idiopathic and spontaneously regressing thrombus in right renal vein and inferior vena cava.

We present the case of a 57-year-old woman with a thrombus in the right renal vein and the inferior vena cava that disappeared spontaneously during 6 months of observation. She had no thrombus-related disease such as kidney cancer, dehydration, multiple myeloma, nephrotic syndrome, or abnormal coagulability. While various examinations were being performed over a 2 month period the thrombus regressed spontaneously. After 6 months of follow-up the thrombus could not be seen on abdominal computerized tomography scan. Twenty months after disappearance of the thrombus the patient is doing well and has no recurrence of thrombus.

Abdomen↗
PubMed1997

Panhypopituitarism due to Rathke's cleft cyst associated with pituitary oncocytoma.

A 38-year-old male with panhypopituitarism due to Rathke's cleft cyst associated with a pituitary oncocytoma is reported. The presenting signs were general myalgia and slight fatigue. Endocrine examinations revealed panhypopituitarism. Magnetic resonance imaging disclosed a suprasellar cystic lesion of the pituitary gland. Cytological examination demonstrated ciliated cells in the mucinous fluid flowing from the cyst during the pituitary operation. A pituitary oncocytoma with randomly scattered S-100 immunoreactive cells was found upon histologic examination of the nodular tissue curettaged from the internal wall of the cyst. These results suggest that the pituitary adenoma was derived from folliculostellate cells included in the Rathke's cleft wall.

Adenoma, Oxyphilic↗
PubMed1995

Thyrotropin-producing pituitary adenoma discovered as a pituitary incidentaloma.

A 46-year-old woman with incidentally discovered thyrotropin (TSH)-producing pituitary adenoma showed endocrine data which was consistent with TSH-producing pituitary tumor. However, she showed only slight hyperthyroidism and the oversecretion and autonomous secretion of TSH from the tumor seemed to be limited from the results of several endocrine examinations. Immunohistochemical examination revealed that not only TSH-beta and TSH-alpha but also prolactin and growth hormone synthesizing cells were present in the tumor tissue. Pituitary-transcription activator 1 (Pit-1) immunoreactivity was also detected in the adenoma cell nuclei. It was conceivable that the presented TSH-producing adenoma clinically located close to the non-functioning adenoma and Pit-1 may have played an important role in the multidirectional differentiation or development of this tumor.

Adenoma↗
PubMed1993

Evaluation of thyroid function in patients with thyroid hormone autoantibodies.

Serum free thyroxine (FT4) levels were measured in patients with Hashimoto's thyroiditis and Graves' disease who were seropositive for thyroid hormone autoantibodies. The methods used were equilibrium dialysis/radioimmunoassay (FT4 by equilibrium dialysis, Nichols Institute) and FT4 analog radioimmunoassay (Amerlex MFT4) before and after treatment of sera with 12.5% polyethylene glycol (PEG). Furthermore, FT4 measurement in the PEG-treated sera was done using two other analog radioimmunoassays (DPC FT4 Kit and N-FT4 Corning). Serum thyrotropin (TSH) concentration before and after i.v. infusion of thyrotropin releasing hormone (TRH) was measured in five cases of Hashimoto's thyroiditis and four cases of Graves' disease with thyroid hormone autoantibodies. Although FT4 determination by analog tracer radioimmunoassays showed unusually high values for the hormone, results obtained by an equilibrium dialysis/radioimmunoassay method showed compatible values with basal TSH. Furthermore, FT4 concentrations measured with Amerlex MFT4 after treatment of sera with 12.5% PEG, correlated well with the values obtained by equilibrium dialysis/radioimmunoassay (r = 0.98, P < 0.001). Similar results were obtained with two other analog FT4 radioimmunoassays after treatment of sera with PEG. These results indicate that real FT4 values in patients with thyroid hormone autoantibodies are compatible with basal TSH concentrations. The presence of thyroid hormone autoantibodies per se does not affect the control mechanism of the hypothalamo-pituitary-thyroid axis. It was concluded that measurement of basal TSH as well as FT4 values by either equilibrium dialysis/radioimmunoassay or analog radioimmunoassays after PEG treatment provides clinicians with valid information for assessment of the precise status of thyroid function in patients with thyroid hormone autoantibodies.

Adolescent↗
PubMed1993

Biological activities of rat antisera raised against synthetic peptides of human thyrotropin receptor.

Twenty three male Wistar rats were divided into five groups and were immunized with five overlapping synthetic peptides (Group I (n = 5), peptide 12-30; Group II (n = 5), 24-44; Group III (n = 4), 308-328; Group IV (n = 5), 324-344; and Group V (n = 4), 339-364) of human thyrotropin receptor (TSHR), which had been conjugated with rabbit serum albumin. Sera obtained 34 days after the first immunization were investigated for their ability to displace 125I-TSH binding to thyrotropin receptor (thyrotropin binding inhibitor immunoglobulins (TBII)). In addition, biological activity, namely thyroid stimulating (TSAb) or blocking (TSBAb) activities in them were tested with cultured porcine thyroid cells. TBII activities in Group I, II, III, IV, and V rats were 12.6 +/- 4.1% (range 9.2-17.2%), 16.3 +/- 4.0% (range 11.7-22.0%), 16.7 +/- 4.9% (range 13.2-20.1%), 14.5 +/- 5.7% (range 8.1-19.0%), and 13.8 +/- 6.3% (range 8.1-14.3%), respectively, which were not significantly different from control rat sera (12.3 +/- 6.7%, range 1.2-20.1%). TSAb activities in Group I, II, III, IV, and V rats were 608 +/- 675% (range 275-1813%), 234 +/- 26% (range 209-265%), 313 +/- 175% (range 187-568%), 190 +/- 63% (range 145-301%), and 134 +/- 24% (range 107-158%), respectively. TSAb activities in Group I, II, III, and IV rats were significantly higher than those from control rat sera (P < 0.01) while those of Group V were not significantly different from control rat sera. None of the rats in each group exhibited TSBAb activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1992

A case of hypothyroidism with simultaneous presence of stimulating type anti-thyrotropin (TSH) receptor antibodies and anti-thyroxine (T4) autoantibodies.

We have examined a hypothyroid patient with stimulating type anti-thyrotropin (TSH) receptor antibodies and without blocking type anti-TSH receptor antibodies. Although she had high serum TSH (240 microU/ml) and low free triiodothyronine (FT3, 0.49 pg/ml) concentrations, which agree with physical findings of hypothyroidism, she had an unusually high free thyroxine (FT4) concentration (3.56 ng/dl). Incubation of her serum with 125I-T4, followed by precipitation with 12.5% polyethylene glycol (PEG) disclosed a higher binding of 125I-T4 (34.4%) than in normal controls, being 5-7%. In addition, binding of 125I-T4 to her serum gamma-globulin was completely displaced by the addition of unlabelled T4. From these results it was concluded that her serum contained anti-T4 autoantibodies. Treatment with synthetic T4 was begun and her thyroid function was monitored by sensitive TSH radioimmunoassay (RIA) and RIA of FT4 after PEG treatment. Since both sensitive TSH RIA and FT4 RIA results after PEG treatment give results concordant with the physical findings, it was concluded that both of the RIA results are useful for the evaluation of thyroid function in patients with thyroid hormone autoantibodies.

Aged↗
PubMed1992

A case of papillary carcinoma of the thyroid associated with parathyroid adenoma without hyperparathyroidism.

A rare occurrence of the association of parathyroid adenoma in a case of thyroid papillary carcinoma is described. The patient was incidentally found to have parathyroid adenoma which was preoperatively diagnosed to be a metastatic lymph node. Analysis of her serum obtained before operation showed an elevation of serum parathyroid hormone (PTH) concentration without hypercalcemia. Since the association of hyperparathyroidism is high in patients with thyroid diseases, examination of not only serum levels of calcium and PTH but also careful interpretation of computed tomography (CT) and/or nuclear magnetic imaging (MRI) is necessary in the diagnosis of co-existing asymptomatic hyperparathyroidism.

Adenoma↗
PubMed1991

Thyroid hormone metabolism and nuclear binding in Gunn rats.

We examined the serum concentrations of total, free thyroid hormones and TSH, activity of hepatic T4 5'-deiodinase, and T3 binding to hepatic nuclei in homozygous (j/j) and heterozygous (j/+) Gunn rats. Both total T3 and free T3 (FT3) concentrations in sera from j/j rats were significantly lower than those of j/+ rats on 5-10, 15-20, and 25-30 days after birth. Both total T4 and free T4 (FT4) concentrations in j/j and j/+ rat sera were not significantly different on 5-10 days. However, in j/j rats they were significantly higher than those of j/+ rats on days 15-20 and 25-30. Serum reverse T3 (rT3) concentrations were higher in j/j than in j/+ rats on days 5-10, 15-20, and 25-30. Serum TSH concentration in j/j and j/+ rats on 15 days post-natal were 1.42 +/- 1.28 and 1.65 +/- 1.24 micrograms/l (mean +/- SD), respectively, which were not significantly different from each other. T3 formation from T4 in hepatic microsomal fractions obtained 15 days after birth was significantly lower in homozygotes than in heterozygotes (4.89 +/- 1.18 vs 11.15 +/- 2.38 pmol/mg protein/min, p less than 0.005). Binding constants (Ka) as well as maximal binding capacities (MBC) for T3 of hepatic nuclei from 15 day-old j/j and j/+ rats were similar (ka; 3.58 x 10(9) vs 3.15 x 10(9) M-1, MBC; 0.316 vs 0.380 pmol/mg DNA). From these results we suggest that decreased conversion from T4 to T3 is one of the major reasons for high serum levels of T4 and rT3, and low levels of T3 in j/j rats, and that nuclear T3 binding and pituitary TSH secretion are unaltered in j/j rats.

Animals↗
PubMed1991

Immunogenetic study of thyroid hormone autoantibodies in a family.

Haplotypes of the human major histocompatibility complex (HLA) and immunoglobulin G heavy chain allotype (Gm) were determined in nine members of a family in which three sisters had thyroid hormone autoantibodies (THAA) in serum. Among three sisters with THAA, two of them were hypothyroid and treated with synthetic thyroid hormones (patients nos. 1 and 2). The other remaining sister (patient no. 3) was euthyroid. Light chain allotype (Km) in them was also examined. Three patients had the same two Gm haplotypes. Km (1) allotype was negative in these three patients. HLA haplotypes of patient no. 1 were the same as those of patient no. 2. However, HLA haplotypes of patient no. 3 were completely different from those of patients nos. 1 and 2. The same combination of Gm haplotypes and the absence of Km (1) allotype were not observed in the remaining members without THAA. These results suggest that genes linked to Gm and Km allotypes are associated with the production of THAA at least in our patients.

Autoantibodies↗