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Biomedical subjects

Y Naoi

Publications and source records attributed to Y Naoi.

At least 19 recordsLinked to original sources
PubMed2001

The functional similarity and structural diversity of human and cartilaginous fish hemoglobins.

Although many descriptions of adaptive molecular evolution of vertebrate hemoglobins (Hb) can be found in physiological text books, they are based mainly on changes of the primary structure and place more emphasis on conservation than alterations at the functional site. Sequence analysis alone, however, does not reveal much about the evolution of new functions in proteins. It was found recently that there are many functionally important structural differences between human and a ray (Dasyatis akajei) Hb even where sequence is conserved between the two. We have solved the structures of the deoxy and CO forms of a second cartilaginous fish (a shark, Mustelus griseus) Hb, and compared it with structures of human Hb, two bony fish Hbs and the ray Hb in order to understand more about how vertebrate Hbs have functionally evolved by the selection of random amino acid substitutions. The sequence identity of cartilaginous fish Hb and human Hb is a little less than 40 %, with many functionally important amino acid replacements. Wider substitutions than usually considered as neutral have been accepted in the course of molecular evolution of Hb. As with the ray Hb, the shark Hb shows functionally important structural differences from human Hb that involve amino acid substitutions and shifts of preserved amino acid residues induced by substitutions in other parts of the molecule. Most importantly, beta E11Val in deoxy human Hb, which overlaps the ligand binding site and is considered to play a key role in controlling the oxygen affinity, moves away about 1 A in both the shark and ray Hbs. Thus adaptive molecular evolution is feasible as a result of both functionally significant mutations and deviations of preserved amino acid residues induced by other amino acid substitutions.

Amino Acid Sequence↗
PubMed2001

Comparison of 99mTc-tetrofosmin uptakes on planar images with those in excised rats organs.

UNLABELLED: The radioactivity in the organs adjacent to the heart causes interference with the quantitative assessment of myocardial uptake of tracer on scintigraphy. In order to investigate how much the functions of these organs affect myocardial uptake seen in imaging, we compared the myocardial uptake measured by means of a gamma camera with the actual activity in the excised organs. METHODS: Thirty-three rats were imaged at 5, 10, 15, 30, 45, 60, 90 and 120 min after the administration of 99mTc-tetrofosmin, and % injected dose per pixel (%ID/pixel) for each organ was assessed on planar images (PI measurement). Percent injected dose per gram of tissue (%ID/g) in the heart as well as lungs, liver, gastrointestines and blood was measured by means of a well scintillation counter (WC measurement). Comparison between PI and WC measurements was performed with % uptake, the PI-to-WC ratio and heart-to-organ ratios. RESULTS: Our WC measurement showed an increase in cardiac uptake until 30 min (1.67 +/- 0.31%) postinjection and subsequent gradual decrease, whereas PI measurement showed maximum activity of 1.81 +/- 0.52% at 15 min postinjection. There was a prominent difference between the two measurements, particularly at 10 min, with a PI/WC ratio of about 1.6 times. Our WC measurement showed maximum pulmonary uptake at 15 min (0.87 +/- 0.31%) and a gradual decrease over 15 min, whereas PI measurement showed maximum uptake at 10 min (1.14 +/- 0.38%). There was hardly any variation in activity observed later than at 10 min. Our WC measurement showed hardly any variance in hepatic activity from 5 min (0.77 +/- 0.19%) to 30 min (0.69 +/- 0.27%) with a subsequent gradual decrease. The percent uptake in PI measurement was generally greater than that in WC measurement, and high values were found at 10 min and 15 min with PI/WC ratios of about 3.3 times and 2.3 times, respectively. CONCLUSION: Percent uptakes in PI measurement were greater than those in WC measurement. The difference between the two measurements was prominent in the early phases. The cardiac uptake in PI measurement was significantly greater than that in WC measurement at 10 min. It was considered that this discrepancy between the two measurements was caused by the Compton scatter from the organs adjacent to the heart.

Animals↗
PubMed2000

New functional polar maps for estimating regional cardiac function using ECG-gated technetium-99m-tetrofosmin SPECT.

OBJECTIVE: The purpose of this work was to develop functional parameters to analyze regional cardiac function using ECG-gated 99mTc-tetrofosmin SPECT. Our goal was to develop a methodology that used slice thickness correction, the generation of a time-activity curve and a polar map. METHODS: Fourteen normal patients without evidence of coronary artery disease were studied. One hour after intravenous injection of 740-1110 MBq (20-30 mCi) 99mTc-tetrofosmin, ECG-gated SPECT data were acquired by dividing a cardiac cycle into 12 frames. The SPECT data were reconstructed from 11 of 12 frames into 3 views. The reconstruction of these images was repeated after performing slice thickness correction. Excluding the effect of different apex-to-base lengths at any frame during a cardiac cycle, 10 short-axis images with the same slice thickness were obtained. Each short-axis image was divided by 40 radii into 40 segments. The time-activity curve was generated from the total counts included in each segment plus both neighboring segments. Subsequently the curve fitting was performed using the second Fourier function. RESULTS: From fitted curves and their differentials, we calculated end-systolic count, end-diastolic count, percent count increase, uptake, peak contraction rate, peak distention rate and contraction time. CONCLUSION: The functional polar maps visually demonstrated regional myocardial function. This method is expected to be helpful for assessing regional cardiac function using 99mTc-tetrofosmin.

Adult↗
PubMed1999

Primary advanced gastric small cell carcinoma: a case report and review of the literature.

We report a 73-yr-old man with primary advanced gastric small cell carcinoma, pure type. A large, Borrman type I tumor was located from the cardia to the entire gastric fundus and upper body. Atypical cells showed a round nucleus, small nucleolus, dense to granular chromatin, and scant cytoplasm. The histological findings indicates an advanced stage and exposure to the gastric serosa. Mitotic figures were observed. There was a proliferation of a sheet-like, solid pattern, but no rosette-like, sqamoid, or glandular patterns. The neoplastic cells were positive for Leu-7 (CD57) and 123C3 (CD56, neural cell adhesion molecule, NCAM) on the surface membrane. We diagnosed this case as primary advanced gastric small cell carcinoma, pure type, and report that Leu-7 and 123C3 monoclonal antibodies are useful markers for gastric small cell carcinoma. The 32 previously reported cases of gastric small cell carcinoma are also reviewed.

Aged↗
PubMed1999

[Linac-based stereotactic radiosurgery for arteriovenous malformations (AVMs) in brain: estimation for efficacy of therapeutic response using angiography].

The purpose of this study was to determine whether it is possible to predict the efficacy of therapeutic response to linac-based stereotactic radiosurgery for AVMs on the basis of the stagnation rate in the nidus, which was defined as follows: [(pooling time of contrast material in the nidus of AVM)/ (intracranial circulation time)] x 100. Cerebral angiograms of twenty-five AVMs were retrospectively evaluated, and the stagnation rates in the nidus were calculated before and one year after stereotactic radiosurgery. Reduction rate was also calculated by using angiography, and we statistically evaluated the relationship between the stagnation rates in the nidus and the reduction rates. The stagnation rates in the nidus prior to linac-based stereotactic radiosurgery were positively correlated with the reduction ratios of AVMs after stereotactic radiosurgery (r = 0.406, p = 0.0432). Our study suggested that a higher stagnation rate in the nidus of the AVM might be obliterated faster after linac-based stereotactic radiosurgery. Thus, calculation of the stagnation rate in the nidus before stereotactic radiosurgery is useful in predicting the efficacy of therapeutic response to linac-based stereotactic radiosurgery for AVMs.

Adolescent↗
PubMed1998

Coexisting primary early gastric plasmacytoma and sarcoidosis with hypercalcaemia.

We report on a 61-year-old woman with coexisting early stage primary gastric plasmacytoma and sarcoidosis with hypercalcaemia. Laboratory data on admission showed hypercalcaemia, with 12.8 mg/dl, parathyroid hormone-related peptide (PTHrP) 1.2 pmol/l, C-PTHrP 69.5 pmol/l, and 1,25-dihydroxyvitamin D3 46.7 pg/ml. Neoplastic plasma cells proliferated in the propria mucosa of the stomach, showed a monoclonal immunoglobulin of cytoplasmic IgA (lambda light chain) and were positive for leucocyte common antigen and epithelial membrane antigen on paraffin section prepared from a stomach biopsy specimen. Russel bodies were present, as were crystals. Abundant sarcoid granulomas were observed in many of the regional lymph nodes around the stomach and in the dermis of a skin nodule. The patient underwent subtotal gastrectomy with administration of antimyeloma chemotherapy. We suggest that the hypercalcaemia in this patient was due to PTHrP production by neoplastic plasma cells.

Cholecalciferol↗
PubMed1997

Breast carcinoma with myeloid metaplasia--a case report.

A 49 year-old female had been suffering from primary myelofibrosis since February 1987 without receiving any treatment. In 1994, a breast mass was detected. Breast tumor biopsy revealed tubular carcinoma with intraductal components and multinucleated giant cells in the loose and myxoid stroma. The giant cells were thought to be megakaryocytes because both Factor VIII and platelet glycoprotein GP IIIa were detected in their cytoplasm. While additional mastectomy specimens and the axillary lymph nodes also revealed prominent myeloid metaplasia, there was no proliferation of the cancer cells. Granulocytic series stained for chloroacetate esterase and very few erythrocytic series were observed. This is the first case in which breast carcinoma and myeloid metaplasia coexisted in the same breast tumor.

Adenocarcinoma↗
PubMed1997

Antinociceptive components of Ganoderma lucidum.

The antinociceptive effects 134 extracts prepared from 45 species of mushrooms were examined by the acetic acid-induced writhing method. From the CH2Cl2 extract of Ganoderma lucidum among the active extracts, ganoderic acids A, B, G and H and compound C6 were isolated as the antinociceptive components.

Acetic Acid↗
PubMed1997

Esophageal intramural pseudodiverticulosis with esophageal cancer improved by target rotation irradiation: case report.

Etiology of esophageal intramural pseudodiverticulosis is still unknown but several accompanying diseases have been reported, for example, reflux esophagitis, esophageal cancer, diabetes mellitus and so on. We have experienced a case of esophageal intramural pseudodiverticulosis with cancer improved by radiation therapy. In this case, there were esophageal cancer in the cervical esophagus, with intramural spreading in whole esophagus. This case was delivered irradiation to the entire esophagus by target rotation method. After irradiation, intramural pseudodiverticula, intramural spreading and primary site of esophageal cancer were improved. This is an interest case report that esophageal intramural pseudodiverticula with cancer was disappeared by radiation therapy.

Aged↗
PubMed1995

Molecular cloning and sequence analysis of a gene encoding an extracellular serine protease from Streptomyces lividans 66.

A gene encoding a homolog of the chymotrypsin-like serine protease (SAM-P20), which was isolated as the target enzyme of a protease inhibitor (SSI), was cloned from Streptomyces lividans 66. This gene contained an open reading frame of 1065 nucleotides encoding 354 amino acid residues with a putative prepro portion of 157 amino acid residues. The deduced amino acid sequence of the cloned gene had significant homology to those of members of Streptomyces extracellular chymotrypsin-like protease family. By Southern blot analysis, it was suggested that protease genes of this type are found at a high frequency in Streptomyces. In this sense, we propose to categorize this protease as a member of the 'SAL' series (SAM-P20-like proteases).

Amino Acid Sequence↗
PubMed1992

[Adverse reactions to low osmolar iodine contrast media (second report)].

From January to December 1990, we performed a prospective survey of adverse reactions to contrast media at two different institutes of Juntendo University. We collected a total of 4555 case sheets during the period. The radiological procedures we investigated were computed tomography, intravenous urography, arteriography, venography and myelography. Low osmolar iodine contrast medium was used almost exclusively (except for five cases). The overall incidence of adverse reactions was 7.0%, and there were no severe or fatal reactions. The incidence of adverse reactions was higher in females (8.5%) than in males (6.1%). The incidence of adverse reactions increased according to the dose of contrast medium, especially when more than 101 ml was injected. Intra-arterial injection caused adverse reactions most often, followed by regular intravenous injections, followed by bolus intravenous injections. Adverse reactions occurred most often during injection. The next occurred in 5 minutes after injection, and then, 5-10 minutes after the injection of contrast medium. The incidence of adverse reactions was higher in patients with a history of allergy or previous reactions. Allergic adverse reactions were observed at a higher frequency. Pretesting was performed in 56.7% of the cases.

Adolescent↗
PubMed1990

[Biliary intervention for malignant obstructive jaundice. Treatment through PTCD fistula].

Currently, diagnosis of obstructive jaundice has become easier with CT and USEG, and percutaneous transhepatic cholangio -drainage (PTCD) for obstructive jaundice has also become much safer using USEG control. We have performed PTCD in 277 cases, from December 1976 to May 1989 at Saitama Cancer Center with specially designed thin needle. And using a PTCD fistula, we have been attempted radiotherapy for 7 cases of the bile duct cancer using Remote After Loading System (RALS), and hyperthermia for 5 cases of bile duct cancer using antenna of microwaves. From autopsy cases, we evaluated treated lesion pathologically, and we obtained the following results. Dosage of biliary RALS need up to 50 Gy at the point of 1 cm from 60Co ++source. Biliary hyperthermia using microwave seem to be unsuccessful, and further improvement to the antenna of microwave were necessary. Furthermore, we have attempted biliary endoprosthesis 27 cases, for better quality of life to the patients with malignant obstructive jaundice. These method seems to be effective in prolonging patient's lives, comparing of cases in which PTCD of an external fistula has been performed.

Adult↗
PubMed1990

[A case report of esophageal intramural pseudodiverticulosis].

A 76 year old man with esophageal intramural pseudodiverticulosis occurring in reflux esophagitis is presented. This unusual condition characterized by multiple small outpouchings in the esophageal wall and associated with a high incidence of benign esophageal stricture. Our case demonstrated typical radiological feature by barium swallow.

Aged↗
PubMed1989

[A case of hepatocellular carcinoma (HCC) with lung metastasis which responded to chemotherapy with a single use of 1-hexylcarbamoyl-5-fluorouracil (HCFU)].

To our knowledge, there has been only one report pertaining to the efficacy of HCFU for treatment of metastatic lung lesion of HCC, so we reported a case of HCC with lung metastasis which responded to chemotherapy with a single use of HCFU. A 64-year-old male was diagnosed as having HCC with lung metastasis by biochemical examination, abdominal CT, hepatic arteriogram and chest X-P. He had been treated previously with gamma-interferon and mitoxantrone, which were assessed as NC and PD, respectively. Two months after last chemotherapy, HCFU was administrated at a dose of 400 mg/body everyday for 8 months. After 4 weeks metastatic lung lesions showed remarkable regression (47% decrease) and disappeared completely 9 weeks later. The size of primary liver tumor gradually decreased during therapy and revealed marked improvement (85.7% decrease) after about 2 months of this therapy. During these periods serum levels of alpha-fetoprotein dropped from 430 ng/ml to less than 10 ng/ml. He is presently still alive and the duration of the PR attained to 35 weeks. As side effects, hypoproteinemia, anorexia and hot sensation were observed.

Antineoplastic Agents↗
PubMed1985

[A case report of cystadenocarcinoma of the liver].

A 65-year-old woman with cystadenocarcinoma of the liver is reported, and 21 Japanese patients cited in the previous literature are reviewed. In our case, CT and US demonstrated a huge solid tumor with calcification in the right lobe of the liver. Angiograms showed a hypovascular tumor with peripheral irregular neovascularity. ERCP showed compression of the extrahepatic bile duct. Right lobectomy of the liver was performed. The pathological diagnosis was cystadenocarcinoma of the liver. In our case, it was difficult to diagnose cystadenocarcinoma because the cystic mass had viscious contents and necrotic tissues, so CT and US showed findings of a solid tumor.

Angiography↗
PubMed1981

Simultaneous detection of several Fusarium mycotoxins in cereals, grains, and foodstuffs.

A systematic method is described for the simultaneous determination of Fusarium mycotoxins (nivalenol, deoxynivalenol, fusarenon-x, diacetoxyscirpenol, neosolaniol, T-2 toxin, HT-2 toxin, butenolide, moniliformin, and zearalenone) in cereals, grains, and foodstuffs. Mycotoxins were extracted with aqueous methanol and purified by a 2-step chromatographic procedure using Amberlite XAD-4 and Florisil columns. The column eluates were concentrated and spotted on a thin layer chromatographic (TLC) plate which was then developed in CHCL3-methanol (93 + 7) and toluene-acetone-methanol (5 + 3 + 2). Each mycotoxin was quantitated by gas chromatography (GC) and TLC densitometry. The minimum detectable concentrations (microgram/kg) in various test materials were: nivalenol, deoxynivalenol, and fusarenon-x, 2.0; diacetoxyscirpenol, neosolaniol, T-2 toxin, and HT-2 toxin, 80; zearalenone, 10; butenolide, 30; and moniliformin, 50. Recoveries of the mycotoxins added to various cereal samples at 1.0-2.0 microgram/g were greater than 71% and averaged 85%.

Chromatography↗