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Biomedical subjects

T Shiina

Publications and source records attributed to T Shiina.

At least 91 records · Page 5Linked to original sources
PubMed1994

L protein, encoded by psbL, restores normal functioning of the primary quinone acceptor, QA, in isolated D1/D2/CP47/Cytb-559/I photosystem II reaction center core complex.

Plastoquinone-9 (PQ-9)-depleted PSII reaction center core complex, consisting of CP47/D1/D2/Cytb-559/I, was isolated from spinach PSII particles. PQ-9, lipids and several proteins were extracted from the original PSII particles and separated by several steps of chromatography to be reconstituted into the isolated complex. PQ-9 reconstituted in the complex with the help of thylakoid lipids (digalactosyldiglyceride) did not function as QA by itself. However, PQ-9 simultaneously reconstituted with L protein and the thylakoid lipids successfully functioned as QA in the complex. Other proteins of PSII origin, such as CP43, H, K, nuclear encoded 4.1 and 5.0 kDa proteins, are unable to restore the QA activity in the complex.

Animals↗
PubMed1993

Eicosapentaenoic acid and docosahexaenoic acid suppress the proliferation of vascular smooth muscle cells.

Eicosapentaenoic acid, which is one of the n-3 polyunsaturated fatty acids (PUFA), is reported to exert its antithrombotic and anti-atherogenic effect partly through the modulation of vascular cell functions. Vascular smooth muscle cell (VSMC) proliferation plays an important role in the pathogenesis of atherosclerosis. We reported the differential effect of various PUFA on VSMC proliferation. First we established a method for preparing PUFA rich cells in culture to mimic the in vivo situation using PUFA triacylglycerol emulsion. Using these fatty acid rich cells, we found that only EPA and docosahexaenoic acid, although less potent than EPA, inhibited the proliferation of VSMC among the fatty acids tested. This effect of EPA was reversed by the addition of anti-oxidants. It is suggested that production of the oxidized species at a low concentration from EPA inhibited the proliferation of VSMC. This anti-proliferative effect of EPA and DHA on VSMC could partly explain the anti-atherosclerotic effect of marine lipids.

Animals↗
PubMed1992

[Results of radiation therapy of extrahepatic bile duct carcinoma].

From January 1975 to August 1988, 40 patients with extrahepatic bile duct carcinoma were treated by external irradiation at Chiba University Hospital and the National Medical Center Hospital. Thirty-four patients (male: 20, female: 14) were evaluable. Eighteen patients were postoperative cases because the surgical margin was positive for tumor cells in the postoperative pathological examination; the other 16 were inoperable cases. Survival in postoperative and inoperable cases was not significantly different, with median survival times of 13.8 and 8.1 months, respectively. Survival in the recanalization-positive and negative-groups was significantly different (p less than 0.05) after irradiation, with median survival times of 13.5 and 6.0 months, respectively. Complications of therapy were recognized in 68% of all cases. They were mainly gastrointestinal symptoms such as nausea, vomiting, erosive gastritis and loss of appetite, but they were not severe. Distant metastasis was recognized in only 4 patients (10%): three had bony metastasis and one had supraclavicular and pulmonary hilar lymph node metastasis. Ninety percent of all cases died from hepatic failure or peritonitis carcinomatosa due to failure to obtain local control by external irradiation. A more effective modality of treatment is necessary to cure these patients.

Aged↗
PubMed1992

Dynamical behavior of psb gene transcripts in greening wheat seedlings. I. Time course of accumulation of the pshA through psbN gene transcripts during light-induced greening.

The time course of the accumulation of the transcripts from 13 psb genes encoding a major part of the proteins composing photosystem II during light-induced greening of dark-grown wheat seedlings was examined focusing on early stages of plastid development (0.5 h through 72 h). The 13 genes can be divided into three groups. (1) The psbA gene is transcribed as a single transcript of 1.3 kb in the dark-grown seedlings, but its level increases 5- to 7-fold in response to light due to selective increase in RNA stability as well as in transcription activity. (2) The psbE-F-L-J operon, psbM and psbN genes are transcribed as a single transcript of 1.1 kb, two transcripts of 0.5 and 0.7 kb and a single transcript of 0.3 kb, respectively, in the dark-grown seedlings. The levels of accumulation of every transcript remain unchanged or rather decrease during plastid development under illumination. (3) The psbK-I-D-C gene cluster and psbB-H operon exhibit fairly complicated northern hybridization patterns during the greening process. When a psbC or psbD gene probe was used for northern hybridization, five transcripts differing in length were detected in the etioplasts from 5-day old dark-grown seedlings. After 2 h illumination, two new transcripts of different length appeared. Light induction of new transcripts was also observed in the psbB-H operon.

Blotting, Northern↗
PubMed1992

Radiation therapy in patients with unresectable hepatocellular carcinoma.

From April 1978 through December 1989, a total of 17 patients with unresectable hepatocellular carcinoma (HCC) were treated with radiation therapy alone or radiation therapy in conjunction with percutaneous ethanol injection (PEI), transarterial infusion chemotherapy (TAI), or transarterial embolization (TAE) at the National Medical Center Hospital. The median survival of all patients was 13.8 months. The survival values determined at 1, 2, and 3 years were 58.8%, 26.1%, and 9.8%, respectively. Only the pretreatment liver function affected the survival value. Between patients who did not have liver cirrhosis (LC) as well as those who had LC of Child's class A and patients who had LC of Child's class B or C, the differences observed in the 1-year survival value and the median duration of survival were statistically significant (P < 0.05). The serum cholinesterase (ChE) level seemed to be a good indicator of liver function during the radiation therapy. A field size of 150 cm2 and a total dose of 5000 cGy (TDF 82) seemed to be well tolerated by patients who did not have LC and those who had LC of Child's class A. The field size determined whether patients with poor liver function such as LC of Child's class B or C would develop severe hepatic deterioration after undergoing radiation therapy.

Aged↗
PubMed1992

Radiotherapy of cholangiocarcinoma: the roles for primary and adjuvant therapies.

A total of 22 patients with cholangiocarcinoma who had been treated with external radiotherapy between 1978 and 1989 were analyzed. Of the 22 patients, 18 had cancer of the hepatic hilus (Klatskin) and 4 had intrahepatic biliary cancer; all but 2 of the subjects had advanced disease. In all, 16 patients underwent primary irradiation for unresectable tumors, 4 were subjected to adjuvant irradiation after gross tumor resection, and 2 received preoperative irradiation followed by gross tumor resection. The mean initial irradiation dose was 52.0 Gy (range, 26-78 Gy). The TDF (time-dose-fractionation) for the entire course of radiotherapy ranged from 49 to 154 (mean, 100). The median survival of all patients was 10 months, and the cumulative 1-year survival value was 37.7%. The external radiotherapy proved to be effective in the treatment of cholangiocarcinoma in terms of palliation and survival.

Adenoma, Bile Duct↗
PubMed1992

An application of ultrasonic tissue characterization to the diagnosis of cataract.

From a therapeutic and pathological point of view, it is important to classify types of cataract and to identify their stages. However, accepted criteria for quantitative diagnosis have not been established. On the other hand, based on the experience from tissue characterization applied to other clinical fields, the attenuation characteristics of the lens are expected to change according to the stage of disease and the type of cataract. In this study from echo signals we tried to measure the attenuation coefficient of the lens with the purpose of quantitatively diagnosing the cataract, and at an early stage. It is shown that the attenuation of the cataractous lens is larger than that of the normal lens and its value depends on the type of the cataract, an indication of the possibility of using tissue characterization in the evaluation of cataract.

Adult↗
PubMed1991

Sequence of hrdB, an essential gene encoding sigma-like transcription factor of Streptomyces coelicolor A3(2): homology to principal sigma factors.

The complete nucleotide sequence of the hrdB gene, an essential gene of Streptomyces coelicolor A3(2), indicates the presence of an open reading frame encoding a putative polypeptide of 442 amino acid (aa) residues with an Mr of 48,412. The principal sigma-like transcriptional factor of S. coelicolor (HrdB) protein showed an extensive aa sequence homology with the known principal sigma factors of Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Myxococcus xanthus. The degree of sequence similarity between HrdB protein and the known principal sigma factors was distinct from that observed between the principal sigma factors and the alternative (minor) sigma factors. Essentially all of the functional domains proposed for the principal sigma factor of E. coli were conserved in HrdB protein. The putative sigma factor, HrdB, like that of B. subtilis had a short internal nonconserved region, which might be characteristic of Gram+ species.

Amino Acid Sequence↗
PubMed1991

Nucleotide sequence of genes hrdA, hrdC, and hrdD from Streptomyces coelicolor A3(2) having similarity to rpoD genes.

The complete nucleotide sequences were determined of hrdA, hrdC, and hrdD from Streptomyces coelicolor A3(2). They indicate the presence of a single open reading frame in each gene coding for polypeptides of 396 (43,747 daltons), 339 (38,173 daltons), and 332 amino acid residues (37,190 daltons), respectively. These amino acid sequences revealed extensive similarities with the principal sigma factors of Bacillus subtilis, Escherichia coli, Mxyococcus xanthus, Pseudomonas aeruginosa, and also the katF gene product of E. coli. Besides the highly conserved amino acid residues in the "rpoD box" region, alignment of hrd gene products and the known principal sigma factors and sigma-related factors allowed us to postulate a common basic structure for the principal sigma type factors as distinct from the alternative sigma factors.

Amino Acid Sequence↗
PubMed1990

[Therapeutic efficacy of postoperative irradiation on carcinoma of the breast].

From July 1973 to October 1983, 77 patients received mastectomy followed by postoperative irradiation at National Medical Center Hospital. The patients were classified as follows: 9 cases as stage I, 30 cases as stage II, 28 cases as stage IIIa, 7 cases as stage IIIb and 2 cases as stage IV. Irradiation fields were the parasternal and supraclavicular region. The axis of the irradiation fields to parasternal and supraclavicular regions were set up at 3.5 cm from the surface of the body and they were irradiated separately. The irradiation fields were about 0.5 cm apart from each other. Parasternal region contained bilateral parasternal lymphnodes. In some cases, the centersplit was used to prevent the radiation myelopathy. Prophylactic irradiation to axilla was performed by electron beam from October 1974 to September 1977. Prophylactic irradiation to chest wall has not been done since 1973. The five and ten years survival rates of stage II were 93.2% and 86.3%, stage IIIa were 61.9% and 55. 7%, Stage IIIb were 71.4% and 35.7%. The rate of the local recurrence at the supraclavicular region was 0% as stage I, 6.7% as stage II, 0% as stage IIIa and 14.3% as stage IIIb. Among the cases with regional lymphnode involvement at the time of mastectomy, the rate of local recurrence at the supraclavicular region was 6.7% in prophylactic irradiation group and it was significantly lower than in non-prophylactic irradiation group (11.5%) (p less than 0.05). The rate of local recurrence to chest wall was 0% as stage I, 6.7% as stage II, 8.0% as stage IIIa and 42.9% as stage IIIb.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Effects of heat treated cells of intestinal lactic acid bacteria in rats fed a deoxycholic acid diet].

Effects of the administration of heat treated cells of intestinal lactic acid bacteria were examined in rats fed a deoxycholic acid (DCA) diet. Male Wistar rats were given a 0.25% DCA diet with or without the heat treated cells of Enterococcus faecalis AD 1001 (EFH-1) or Lactobacillus reuteri AD 0002 (LRH-2) for 4 weeks. Abnormal increases in serum GOT, GPT, UN and lipoproteins were observed in the rats fed the DCA diet. Furthermore, severe lesions in the kidney as well as in the liver were found in these rats. On the contrary, the increases in serum GOT, UN, VLDL and LDL were significantly suppressed, and markedly fewer lesions in the liver and the kidney were observed in the rats fed the DCA diet plus EFH-1 or LRH-2.

Animal Feed↗
PubMed1990

[A case of subacute cerebral infarction demonstrating hyperemia and crossed cerebellar diaschisis in I-123 IMP SPECT].

SPECT with N-isopropyl-p-[I-123]iodoamphetamine were performed in a 81-year-old man with cerebral infarction. In the subacute phase, the radioactivity was increased in the infarct area where fogging effect and remarkable contrast enhancement was demonstrated in X-ray CT. The contralateral cerebellar hemisphere showed reduced activity due to crossed cerebellar diaschisis (CCD). In the chronic phase, the decrement of the activity in the infarct was observed. Increased activity in the subacute phase was thought to reflect the hyperemia in the infarct, while CCD suggested the decreased metabolic activity in the lesion. The coexistence of the hyperemia and the CCD indicates flow and metabolic uncoupling, which means "luxury perfusion". This case was also thought to demonstrate atypical findings of CCD in SPECT imaging.

Aged↗
PubMed1990

[Evaluation of pontine visualization with single photon emission computed tomography using N-isopropyl-p-(I-123)iodoamphetamine in normal and pathological cases].

Pontine visualization with single photon emission computed tomography (SPECT) using N-isopropyl-p-[I-123]iodoamphetamine (I-123 IMP) was evaluated in 99 cases including 46 cases of brain infarction, 25 of other cerebrovascular disorders and 28 of brain tumor and in 19 normal subjects. In each case, SPECT using a rotating gamma camera was started at 30 minutes after intravenous administration of 111 MBq of I-123 IMP. Transverse images were reconstructed parallel to the cantho-meatal line and displayed on films. Pontine visualization was visually classified into three grades: high radioactive accumulation confined to the pons with clear contour (Grade 3), faint accumulation with indistinct contour in the pontine region (Grade 1), the pontine accumulation was identified but its activity was less significant (Grade 2). The results showed that grade of the pontine accumulation was lower in pathological cases compared to normal subjects. Six cases with brain stem lesion demonstrated pontine accumulation of grade 1 in 4 case and of grade 2 in 2 cases. Lower grade was also revealed in 29 cases with crossed cerebellar diaschisis (CCD). No significant correlation was observed between classified grade of pontine accumulation and maximum counts of reconstructed images. We concluded that SPECT could detect brain stem lesions and that lower accumulation in pons with CCD positive cases was thought to partially reflect the reduced blood flow and metabolism in the pontine nuclei.

Adolescent↗
PubMed1989

Interrelationship between urinary kallikrein and arginine-vasopressin in man.

Physiological saline solution was infused in 9 normal subjects and 6 patients with central diabetes insipidus (DI). At 120 min after the start of infusion, arginine vasopressin (AVP) was injected (i.m.). Urine was collected every 30 min fraction. The urinary excretion of kallikrein-like activity (KAL-A) (S-2266 hydrolysis activity) was significantly lower in patients with DI than in normal subjects, without showing the differences of plasma renin activity (PRA), plasma aldosterone concentration (PAC), creatinine clearance (Ccr) and blood pressure between the two groups, except a marked water-diuresis in DI. The urinary excretion of KAL-A correlated positively with the urinary excretion of AVP. AVP administration significantly increased the urinary excretion of KAL-A. After overnight fasting, an acute oral water-loading was carried out for 15 min in 6 normal subjects. Concomitant with a significant suppression of the level of plasma AVP from the first 30 min, a slight, but significant, decrease in urinary excretion of KAL-A was observed in the first 30 min fraction after loading, compared with the control period. Afterwards, the urinary excretion of KAL-A increased prominently with an increase in urine flow. KAL-A in the urine decreased promptly from the first 30 min fraction and then gradually until 120 min after loading. Urine volume and free-water markedly increased except the first 30 min fraction, compared with the control period. Thus it is suggested that AVP is one of factors which actually regulate the secretion of renal kallikrein in man.

Adult↗