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T Takeshima

Publications and source records attributed to T Takeshima.

At least 73 records · Page 4Linked to original sources
PubMed1992

Molecular cloning of the gene encoding Thiobacillus ferrooxidans Fe(II) oxidase. High homology of the gene product with HiPIP.

The amino-terminal sequence of Thiobacillus ferrooxidans Fe(II) oxidase (linked to cytochrome c552) was determined, and the iro gene that encodes this enzyme was cloned using degenerate oligonucleotides as a probe. The DNA sequence of a region (856 base pairs) which encompasses the iro gene revealed that the enzyme was encoded by a 273-base pair open reading frame and consists of 90 amino acids, including a possible 37-residue signal sequence. The iro gene seems to be transcribed independently of any other gene because the transcriptional products are 0.45 and 0.6 kilobases in size. Current protein databases revealed that the iro gene product is a new member of the high redox potential iron sulfur proteins, which generally function in electron transport but do not show enzymatic activity.

Amino Acid Sequence↗
PubMed1992

Secretory meningioma with elevated serum carcinoembryonic antigen level.

We recently encountered a 68-year-old woman with right sphenoid wing meningioma of the secretory type accompanied by an elevated serum carcinoembryonic antigen level. This case was neuroradiologically characterized by marked brain edema. Histologically, the lesion was rated as having meningothelial components and was rich in blood vessels and pseudopsammoma bodies. Carcinoembryonic antigen, epithelial membrane antigen, keratin, and cytokeratin were immunohistochemically detected in the pseudopsammoma bodies and the cells producing these bodies.

Aged↗
PubMed1992

Electrotransformation of Thiobacillus ferrooxidans with plasmids containing a mer determinant.

The mer operon from a strain of Thiobacillus ferrooxidans (C. Inoue, K. Sugawara, and T. Kusano, Mol. Microbiol. 5:2707-2718, 1991) consists of the regulatory gene merR and an operator-promoter region followed by merC and merA structural genes and differs from other known gram-negative mer operons. We have constructed four potential shuttle plasmids composed of a T. ferrooxidans-borne cryptic plasmid, a pUC18 plasmid, and the above-mentioned mer determinant as a selectable marker. Mercury ion-sensitive T. ferrooxidans strains were electroporated with constructed plasmids, and one strain, Y4-3 (of 30 independent strains tested), was found to have a transformation efficiency of 120 to 200 mercury-resistant colonies per microgram of plasmid DNA. This recipient strain was confirmed to be T. ferrooxidans by physiological, morphological, and chemotaxonomical data. The transformants carried a plasmid with no physical rearrangements through 25 passages under no selective pressure. Cell extracts showed mercury ion-dependent NADPH oxidation activity.

Blotting, Southern↗
PubMed1992

[Reproductive and developmental toxicity studies of FUT-187. (III)--Postnatal study in rat F1 offspring from dams treated orally with FUT-187 during the period of fetal organogenesis].

A postnatal study of F1 offspring exposed to FUT-187 during fetal organogenesis was carried out using Crj : CD rat. FUT-187 was dosed by gavage at 0, 50, 200 and 800 mg/kg/day from day 7 to 17 of gestation. All pregnant rats were allowed to deliver newborns, and F1 offspring were examined for development indices and reproduction and learning ability. Effects at 800 mg/kg included temporary salivation, body weight depression and decreased food intake. There were no adverse effects on delivery and lactation and no significant changes on neonatal development, growth, reproduction and learning ability in the F1 offspring. These results indicate that the no effect dose level of FUT-187 is 200 mg/kg/day in dams, and 800 mg/kg/day in offspring.

Abnormalities, Drug-Induced↗
PubMed1992

[The focal brain ischemia with disturbance of venous drainage].

The focal brain ischemia with disturbance of cerebral venous drainage often lead to brain edema and hemorrhagic infarction and make mortality and morbidity worse. So we tried to make sure of this fact using a middle cerebral artery (MCA) occlusion model in adult cat. The MCA was exposed by the transorbital approach and temporally obstructed by Zen's clip. We divided the animals into two groups of eight cats. One group is only MCA occlusion group (sham group) and the other in MCA occlusion with disturbance of venous drainage (VRD group). We ligated bilateral external jugular vein (EJV) and internal jugular vein (IJV) and injected embolic sources from the left EJV to obstruct the venous system of cat brain. The pressure of superior sagittal sinus was increased up to 18.7 +/- 5.3 mmHg by this method. A cranial window was made above the ectosylvian gyrus, which has poor anastomosis. The reactivity of pial arteriole and regional cerebral blood flow (rCBF) were observed through the window. And histological brain examination was also performed. The result was that the reactivity of pial arterioles was severely disturbed in VRD group. The area of cerebral infarction and edema were also significantly expanded in VRD group. Considering from these facts, when the venous drainage was disturbed, cerebral perfusion pressure relatively decrease. Because of the decrease in cerebral perfusion pressure, cerebral infarction and edema probably expand to the area so called penumbra.

Animals↗
PubMed1992

[Purine catabolites and pial arteriolar diameter in transient cerebral ischemia].

In transient cerebral ischemia, extracellular purine catabolites and pial arteriolar diameter were measured continuously. Ischemia during one hour was induced by unilateral occlusion of left middle cerebral artery in feline. Extracellular purine catabolites were sampled by in vivo brain microdialysis technique from the gray matter at ectosylvian gyrus. These catabolites were analyzed by HPLC system. Simultaneously, reactivity of pial arteriole was observed and its diameter was measured through the cranial window using intravital microscope and width analyzer. Extracellular concentrations of adenosine, inosine, hypoxanthine and xanthine were found to be 0.80 +/- 0.16 microM, 2.01 +/- 0.95 microM, 4.01 +/- 2.73 microM and 3.93 +/- 2.39 microM, respectively. During ischemia, the concentration of adenosine increased 8.7-fold and arteriolar diameter was 170% of the resting state. These findings in extracellular adenosine concentration and pial arteriolar diameter during ischemia support a role of adenosine in regulation of cerebral blood flow. After reperfusion, arteriolar diameter had returned to 120% of the resting state. But 50 min after reperfusion, pial arteriole began to dilate again coincident with the peak of xanthine concentration. These results suggest that free radicals were produced and could affect pial arterioles 50 min after reperfusion.

Adenosine↗
PubMed1992

[The hemodynamics of intracranial aneurysm by transcranial Doppler arteriography].

The use of an ultrasonic transcranial Doppler arteriography (TCDA) technique for noninvasive diagnosis of cerebral aneurysm is described. Twenty one patients with intracranial aneurysm previously diagnosed by conventional angiography were evaluated with Trans-Scan (EME). Mapping image was used as a guide to identify parent artery and aneurysm. In four patients, we could not record aneurysmal blood flow because of their poor or non existent acoustic window. Good images were recorded in 17 patients. The location of aneurysms were A-com (1 case), Distal ACA (2 cases), IC (7 cases), MCA (3 cases), Basilar (1 case) and IC fusiform (3 cases). Two types of Doppler spectra were obtained from the aneurysmal blood flow. One was characterized by a high density zone along the base line and the other was characterized by a homogeneous high density zone. In both types, Doppler sound was characterized by low frequency sound. The low frequency sound reflects the turbulent flow in the aneurysm. The pattern of Doppler spectra obtained from ordinary arteries was characterized by a high density zone along the descending limb of the envelope. Doppler sound is characterized by high frequency sound. A homogeneous spectral pattern was obtained in both aneurysms and ordinary arteries. But it was possible to differentiate them by Doppler sound. Consequently to be able to hear Doppler sound is very important. We were able to detect fourteen of seventeen aneurysms (A-com 1/1, Distal ACA 1/2, IC 7/7, MCA 2/3, Basilar 1/1, and IC fusiform 2/3). The rate of detection was 82 percent. Aneurysm size ranged from 5mm x 4mm to 16mm x 18mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Human herpesviruses infections (I)--EBV infection and immunity in cancer patients].

Human herpesviruses have been known to be reactivated from latent infection iin immunosuppressed individuals. To assess the immunity, antibodies to human herpesviruses (VZV, HSV, CMV and EBV) were measured in patients with gastrointestinal cancer and normal persons ranging from 40 to 80 in age. CF antibodies to herpesviruses except for EBV were negative in normal persons below the age of 60 and cancer patients aged 60 and over. The CF antibody titer higher than 1:64 occurred only in young cancer patients and older normal persons. The titer of VCA antibody to EBV ranged from 1:40 to 1:160 in more than 80% of normal persons and was higher than 1:640 in less than 7%. The ratio those with antibody negative or below 1:40 increased with the age. In contrast, the titer was higher than 1:320 in 70% of the patients, and the antibody was negative in none of them. In addition, the low titer occurred only in less than 5%. The rate of patients having higher VCA antibody titers increased with age, and the titer was high in more than 50% of patients in the 8th decade. In cancer patients, the higher the VCA antibody titer was, the less number of mature B cells, target cells of EBV, and the B cell functions were observed. This suggests that reactivation of EBV in hosts bearing carcinomas results in a fall of production of the specific antibody.

Adult↗
PubMed1991

Evidence for two sets of structural genes coding for ribulose bisphosphate carboxylase in Thiobacillus ferrooxidans.

Previously, we reported the cloning of the ribulose-1,5-bisphosphate carboxylase genes (rbcL1-rbcS1) of Thiobacillus ferrooxidans Fe1 (T. Kusano, K. Sugawara, C. Inoue, and N. Suzuki, Curr. Microbiol. 22:35-41, 1991). With these genes as probes, a second set of ribulose-1,5-bisphosphate carboxylase genes (rbcL2-rbcS2) was identified in the same strain and cloned. rbcL1 and rbcL2 encode the large subunits, and rbcS1 and rbcS2 encode the small subunits. Similar restriction patterns between these gene sets suggested a high level of sequence homology. In fact, sequence analysis showed that a 2.2-kb region, including the entire large and small subunit structural genes, was totally conserved in rbcL1-rbcS1 and rbcL2-rbcS2. The rbcL1 (rbcL2) and rbcS1 (rbcS2) genes were 1,422 and 333 bp in length and encoded 473- and 110-amino-acid proteins, respectively. The genes were separated by a 90-bp spacer sequence and were preceded by possible ribosome-binding sites. The N-terminal amino acid sequences of the subunit proteins, synthesized in Escherichia coli, were determined by Edman degradation and found to agree with the deduced amino acid sequences, except for the N-terminal methionine residue. The transcriptional start site of the rbc genes was determined by primer extension, and the size of the rbc transcript was estimated to be about 2.1 kb, suggestive of the cotranscription of rbcL1-rbcS1 and/or rbcL2-rbcS2 mRNAs. Comparisons of amino acid sequences of both subunits with those of other organisms revealed that the ribulose-1,5-bisphosphate carboxylase of T. ferrooxidans, a chemoautotrophic bacterium, is phylogenetically closer to the photosynthetic bacterium Chromatium vinosum than to another chemoautotrophic bacterium, Alcaligenes eutrophus.

Amino Acid Sequence↗
PubMed1991

Survey of Hanganutziu and Deicher antibodies in operated patients.

The appearance of Hanganutziu and Deicher (HD) antibody in the sera of patients suffering from various diseases, including malignancies of some organs and liver disorders, was investigated by enzyme-linked immunosorbent assay using N-glycolylneuraminyl-lactosylceramide (HD3) and 4-O-acetyl-HD3 as the antigenic molecules. More than 25% of sera from patients suffering from malignancies, cholelithiasis and liver cirrhosis had HD antibody, whereas none of 41 sera from healthy persons had HD antibody. The percentage of HD antibody-positive patients was similar in stages I, II and III of gastric cancer and recurrence cases. Antibody titers of the positive patients in each stage were also not different from those in each other stage. These results indicated that HD antigenic expression on cancerous tissue is not dependent on the cancerous malignancy. The HD antibody level was elevated after surgical removal of cancerous tissues in 5 of 6 patients examined, indicating that tumor growth absorbed the serum antibody. Serum antibody against 4-O-acetyl-HD3 was detected independently of HD3 antibody in some cases; however, in most cases, correlation between the two antibody titers was observed.

Aged↗
PubMed1991

[Cryopreservation of mouse spermatozoa].

The spermatozoa of cauda epididymis of mature mice were suspended in 3% skim milk in distilled water supplemented with 12, 15, 18 or 21% (W/V) raffinose. The suspension of spermatozoa were frozen in liquid nitrogen gas for 10 min, then stored in liquid nitrogen (-196 degrees C). The frozen suspensions of spermatozoa were thawed by rapid warming in water bath at room temperature. For removing the cryopreservative solution, a pair of syringes connected with a three stop cock and a filter unit (pore size 0.45 mu) were used. Highest sperm motility was obtained after 1 hr of thawing from the cryopreservative solution containing 18% raffinose and 3% skim milk. These cryopreserved spermatozoa were used for fertilization in vitro. The proportion of pronuclear oocytes was 35.9% (74/206) 6 hr after insemination, and the proportion of 2-cell embryos was 33.6% (42/125) 28 hr after insemination. All 2-cell embryos were transferred to the oviducts of pseudopregnant recipients and 45.2% (19/42) developed to normal young.

Animals↗
PubMed1990

Headaches in dementia.

We investigated 288 elderly subjects with various degree of dementia, focusing on headaches. Seventy-three of 288 elderly subjects (25.3%) complained of some headaches. The most common type was the tension-type headache, from which 43 of the 73 subjects with headaches (58.9%) suffered. The degree of cognitive disturbances, evaluated by Hasegawa's intelligence scale, significantly correlated to the prevalence of headaches, and indicated that patients with dementia appeared to have less headaches. The methodological issues and views on headache research in dementia were assessed, and it is concluded that the field is a difficult one, with potential for error.

Activities of Daily Living↗
PubMed1990

Hematological changes in the mice transplanted with methylcholanthrene-induced fibrosarcoma.

Hematological values of the peripheral blood in the mice transplanted with methylcholanthrene-induced fibrosarcoma were examined. Values for red blood cells and platelets reduced after tumor transplantation. Values for white blood cells increased with the percentage of neutrophils being increased significantly. Phagocytic activity of neutrophils from the tumor-bearing mice was not reduced. The cultured fluid of the tumor used in the experiments possessed strong colony stimulating activity to bone marrow cells.

Animals↗
PubMed1989

Muscle contraction headache and migraine. Platelet activation and plasma norepinephrine during the cold pressor test.

For clarification of possible platelet activation in migraine and chronic muscle contraction headache (MCH) under stress, plasma platelet factor 4 (PF4), norepinephrine (NE), and free fatty acids (FFA) were investigated during the cold pressor test. Both PF4 and NE increased significantly, whereas FFA showed no remarkable changes. The increases of PF4 in MCH and migraine during this test were significantly greater than in healthy controls. The increase of PF4, however, was independent of NE increase and FFA changes. On the other hand, we observed decreased NE levels in both MCH and migraine, which might suggest peripheral sympathetic hypofunction. The platelets of MCH or migraine patients seem to be impaired, and the impairment may be caused by continuous sympathetic hypofunction. The behaviour of the above three substances in MCH was similar to that in migraine throughout the present study.

Blood Platelets↗
PubMed1989

A neuroendocrinological study in female migraineurs: prolactin and thyroid stimulating hormone responses.

To evaluate the change of the neurotransmitter function in migraine, a neuroendocrinological study was performed in eleven female migraineurs and nine female controls. Thyrotropin releasing hormone, luteinizing hormone releasing hormone, and insulin were simultaneously loaded (the Triple test). Before and after loading, serum glucose, prolactin (PRL), thyroid stimulating hormone (TSH), luteinizing hormone, follicle stimulating hormone, adrenocorticotropic hormone, cortisol, human growth hormone and beta-endorphin were measured. The Triple test produced an increase of PRL in both migraine and control groups, but in migraineurs the increase was significantly larger than in controls. TSH also increased in response to the test, but the TSH response in patients was less than in controls, although not significantly so. The responses of other substances showed no significant differences between the two groups. Although dopaminergic hypofunction in migraine has been proposed by some authors, the present findings rather suggest a serotonergic hyperfunction.

Adolescent↗
PubMed1989

Cardiovascular sympathetic hypofunction in muscle contraction headache and migraine.

There have been some recent reports proposing that muscle contraction headache (MCH) and migraine are similar and may have a common etiology. It has been hypothesized that derangement of the autonomic nervous system (ANS) plays an important role in the pathogenesis of migraine. However, reports on the ANS function in MCH have rarely been submitted. Therefore, in this report, MCH patients were investigated as well as migraine patients. The cardiovascular reflex responses by orthostatic test, isometric work test and the pulse rate (R-R interval) variation in fifteen MCH patients and fifteen migraine patients were recorded during headache-free intervals. The plasma norepinephrine (NE) levels were also measured throughout the orthostatic tests. Fifteen healthy subjects served as the age-matched control group. In the MCH group and the migraine group, blood pressure immediately after going from the supine to the erect position decreased more significantly than in the control group. The basal NE level was significantly low in both the MCH group and the migraine group, in comparison with the control group. MCH patients as well as migraine patients showed cardiovascular sympathetic hypofunction.

Adult↗