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T Araki

Publications and source records attributed to T Araki.

At least 109 records · Page 6Linked to original sources
PubMed2001

Accumulation of calcium in the arteries of Japanese monkey.

To examine whether the calcium accumulation in the arteries is related to the way of walk or not, the calcium contents were determined in various arteries of Japanese monkeys of quadrupedal walk by inductively coupled plasma-atomic emission spectrometry. Japanese monkeys consisted of five males and four females, ranging in age from 2 to 29 yr. Age-related changes of the calcium content were examined in various monkey arteries. Significant relationships between age and calcium content were found in the arteries, such as the axillary, brachial, radial, subclavian, common carotid, common iliac, and femoral arteries, but not statistically in the thoracic and abdominal aortas, ulnar, external iliac, internal iliac, popliteal, and tibial arteries. The average contents of calcium were compared between the two groups of the monkeys below 14 yr and over 24 yr of age. Below 14 yr, the calcium content was a little higher in the arteries, such as the common, external and internal iliac, and femoral arteries than that of the other ones. Over 24 yr, the calcium content increased remarkably in the arteries, such as the thoracic aorta, common, internal and external iliac, common carotid, and subclavian arteries. The calcium contents of the thoracic aorta, common, internal and external iliac, common carotid, and subclavian arteries increased by more than two times over 24 yr compared with those below 14 yr. In a comparison between the calcium contents of the arteries in the anatomically corresponding regions of the upper and lower limbs, no statistically significant differences were found in the subjects over 24 yr as well as the subjects 2-29 yr of age. The calcium accumulation in the arteries of monkeys with aging was different from those in the arteries of humans, because in the case of human, a very high accumulation of calcium occurred in the arteries of the lower limb with aging in comparison with those in the upper limbs. Therefore, it is likely that different ways of walk or different species are partly affected in the calcium accumulation in the arteries with aging.

Aging↗
PubMed2001

Changes in maternal peripheral T helper 1-type and T helper 2-type immunity during labor.

The percentages of Th1 and Th2 cells and the Th1:Th2 ratios in peripheral blood from 22 patients with a singleton pregnancy at 30 and 36 weeks' gestation, on admission for the spontaneous onset of labor pains, at 1 minute after placental delivery and on day 7 after delivery were determined using flow cytometry. The percentages of Th1 and Th2 cells and the ratio of Th1:Th2 did not markedly change during 30 weeks' gestation and 1 minutes after placental delivery. However, the percentage of Th2 cells had decreased significantly at 7 days after delivery. In addition, the Th1:Th2 cell ratios were significantly elevated on day 7 after delivery. Thus, the termination of pregnancy may not be associated with a change in maternal Th1:Th2-immunity.

Adult↗
PubMed2001

Management of severe blunt liver injuries.

To assess the effectiveness of non-surgical treatment for severe blunt liver injuries, we retrospectively examined the files of 147 patients (excluding cases with cardiopulmonary arrest on arrival). The patients were divided into three groups according to the date of admission: Group-A (1982-85), B (1986-90) and C (1991-95). The patients were further divided on the basis of the type of injury, according to the classification proposed by the Japanese Association for the Surgery of Trauma (JAST). The types of injuries reported here were of type II, IIIa or IIIb. There was no difference in the patients' background, injury severity score (ISS), amount of intra-peritoneal hemorrhage, and amount of blood transfusion among the three groups, A, B and C. Surgical treatment was carried out in all Group-A patients, in 81.8% of Group-B patients and in 31% of Group-C patients. The hospitalization period was shorter in the Group-C, and the frequency of fatal outcome was also lower in Group-C. Non-surgical treatment has been performed since 1988 in our center, and its frequency has been increasing since then. It was applied to 6 cases (18.2%) of Type II injuries in Group-B. In total, 69% of the cases in Group-C were non-surgically treated, including cases of Type IIIa and Type IIIb injuries. Non-surgical treatment prevented 8 out of 9 cases of severe liver injury from having fatal outcomes in 1995. Moreover, 5 of those cases were of the most serious type (Type IIIb). There were three fatalities in Group-C and none in Group-B. Out of all the non-surgically treated cases, injuries to the head were the cause of fatality. Any treatment of cases showing inferior vena cava damage was generally ineffective due to heavy bleeding, unless the bleeding was stopped by surgical intervention. Non-surgical treatment is suitable for blunt liver injuries, including severe liver injuries, provided that bleeding control and close observation are maintained.

Adult↗
PubMed2001

[Two elderly patients with sarcoidosis and Sjögren's syndrome].

Two elderly patients with sarcoidosis complicated with Sjögren's syndrome are described. Case 1: A 70-year-old woman was admitted due to dry eyes. Histological examination of a minor salivary gland specimen revealed lymphocytic infiltration, which was compatible with Sjögren's syndrome. Because uveitis was demonstrated, transbronchial lung biopsy (TBLB) was performed, to confirm a diagnosis of lung sarcoidosis. Histological examination of TBLB showed non-caseating granulomas compatible with sarcoidosis. Case 2: A 70-year-old woman was admitted due to dyspnea on exercise and blurred vision. Two years previously, Sjögren's syndrome was diagnosed because of a positive Shirmer test and positive SS-A antibody. Result of ophthalmic examination were compatible with uveitis. Histological examination of TBLB showed non-caseating granulomas compatible with sarcoidosis. Certain similarities between sarcoidosis and Sjögren's syndrome in terms of immunological aspects have attracted attention. In the present manuscript, a possible relationship between the two diseases as well as the characteristics of elderly sarcoidosis are discussed.

Aged↗
PubMed2001

Three aberrant splicing variants of the HMGIC gene transcribed in uterine leiomyomas.

Cytogenetic aberrations involving chromosome region 12q13-15 occur frequently among benign mesenchymal tumors in humans, e.g., pleomorphic adenomas of the parotid gland, pulmonary chondroid hamartomas, lipomas, or uterine leiomyomas. HMGIC, a gene encoding a protein of the high-mobility group, has been identified as a target of those events. Using the 3' rapid amplification of cDNA ends (RACE) technique, we identified six different fusion transcripts of the HMGIC gene among 13 uterine leiomyomas; three of these variants had not been described before. Radiation-hybrid mapping located all three of the novel fusion transcripts in the same chromosomal region as the HMGIC gene. Cloning of the entire HMGIC gene in a genomic contig of P1-derived artificial chromosomes and cosmids revealed that the 3' portion of each novel fusion transcript contained cryptic exonic sequences (designated a, b, and c) present in intron 3 of the HMGIC gene. Thus, aberrant alternative splicing was responsible for abnormal HMGIC isoforms in those myomas. Identification of these novel variants suggested that aberrant splicing can join chromosomal translocation and inversion as a mechanism for producing abnormal HMGIC transcripts, and that separation of the DNA binding domains of HMGIC from its acidic carboxyl-terminal regulatory domain can lead to development of benign mesenchymal tumors.

Alternative Splicing↗
PubMed2001

[Changes in serum malondialdehyde-modified low-density lipoprotein in patients with acute myocardial infarction and stable angina pectoris treated by coronary angioplasty].

OBJECTIVES: Serum malondialdehyde-modified low-density lipoprotein(MDA-LDL) was measured as a marker of oxidative stress, and the changes in serum MDA-LDL compared in patients with acute myocardial infarction and stable angina pectoris treated by percutaneous transluminal coronary angioplasty (PTCA). METHODS: Forty-one patients with acute myocardial infarction or stable angina pectoris were admitted to our hospitals between January 2000 and June 2000. Direct PTCA was performed in 17 patients(MI group) and elective PTCA in 24 patients(AP group). Coronary angiography was performed in nine control subjects(control group). Serum MDA-LDL was measured in the peripheral venous blood before and immediately after procedures in each group(normal range 20-80 U/l). RESULTS: There were no significant differences in patient characteristics, except age, between the MI group and AP group. Serum MDA-LDL was elevated above the normal range before the procedure in both groups(MI group 104.7 +/- 52.0 U/l, AP group 99.7 +/- 42.8 U/l), and significantly decreased immediately after the procedure(MI group 61.3 +/- 25.6 U/l, AP group 62.0 +/- 29.6 U/l), but there were no significant differences between the two groups. Serum MDA-LDL was elevated before the procedure (99.3 +/- 48.9 U/l) in the control group and significantly decreased immediately after the procedure(61.7 +/- 26.2 U/l). However, these values did not differ from the values before and immediately after the procedure in the MI group and the AP group. The percentage changes in serum MDA-LDL before and immediately after the procedure were -38 +/- 16% in the MI group, -37 +/- 17% in the AP group and -36 +/- 20% in the control group, and there were no significant differences between the three groups. CONCLUSIONS: No significant difference in the changes in serum MDA-LDL was observed between patients with acute myocardial infarction and stable angina pectoris treated by PTCA. However, anticoagulants may affect the MDA-LDL measurements directly, because similar changes in serum MDA-LDL were observed in control subjects after only coronary angiography.

Age Factors↗
PubMed2001

[Dynamic MRI].

Explore the source record for details and available documents.

Carcinoma, Hepatocellular↗
PubMed2001

[A patient with restless legs syndrome/periodic limb movement successfully treated by wearing a lumbar corset].

We report a 77-year-old woman with restless legs syndrome(RLS) and periodic limb movement(PLM). From 62 years of age, she was awakened by tingling and involuntary movement in her legs during sleep. There symptoms disappeared when she stood up and walked. She was treated with clonazepam (2.5 mg/day) and valproate (400 mg/day) at 77 years of age, and the symptoms clearly ameliorated. However, she developed mild truncal ataxia and was referred to our hospital. On admission, neurological examination revealed Babinski and Chaddock signs bilaterally with depressed tendon reflexes in the lower limbs, mild truncal ataxia and horizontal gaze nystagmus. She did not present with involuntary movement of the legs while taking the anti-epileptic drugs. Cessation of these drugs alleviated the truncal ataxia and nystagmus, but reexacerbated abnormal sensation with involuntary movement in her legs during sleep. The involuntary movements in her legs were slower than myoclonus and resembled a Babinski reflex (duration about 1 second), and they appeared periodically (around every 30 seconds) in I-II sleep stages. Neither brain MRI nor EEG detected any abnormality. Cervical MRI revealed focal compression of the spinal cord by osteophytes at C5-C6 (more severe on the left side). Motor evoked potentials with transcranial magnetic stimulation revealed a mild delay in the central conduction time (CCT), which was more prolonged on the left side. She was thus diagnosed as having RLS/PLM with involvement of the bilateral pyramidal tracts. Although nerve conduction studies did not detect any abnormality in the peripheral nerves, RLS/PLM of the left leg was induced by electric stimulation of the left tibial nerve. Because she did not want medication any more, we treated her with a lumbar corset, hoping that wearing a lumbar corset might induce contraction of the truncal muscles that would mimic standing and walking or might produce additional sensory input that would induce a 'sensory trick'. Consequently, her abnormal sensation and involuntary movement during sleep as well as the stimulation of the tibial nerve disappeared. Wearing a lumbar corset may inhibit the excitability of the spinal cord that generates RLS/PLM, though the level of sensory input by the corset was higher than the input level of abnormal sensation in her legs. A lumbar corset may be a useful alternative choice for patients with RLS/PLM, who cannot tolerate either anti-epileptic or dopaminergic drugs.

Aged↗
PubMed2001

[A case of MELAS presenting complex partial status epilepticus].

We reported a 37-year-old man who presented complex partial status epilepticus as the initial symptom of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS). He showed fluctuating consciousness disturbance, left homonymous hemianopsia, and paroxysmal conjugated eye deviation to the left. The lactic acid level was elevated in blood and CSF, and ragged-red fibers were observed in the biopsied muscle. MRI demonstrated T2-prolonged lesions in the right occipito-parieto-temporal lobes. Since a mutation of mitochondrial DNA (A3243G) was identified, he was diagnosed as having MELAS. On an ictal record, high amplitude, rhythmic sharp waves were observed at right parieto-temporo-occipital region. High amplitude slow waves were also observed on the right hemisphere, especially in the right frontal lobe. These ictal discharges gradually decreased at their amplitude and in frequency, and then ictal EEG turned to the interictal EEG. During an ictal period, conjugated eye deviation to the left side and consciousness loss were observed. These seizures were observed once every several minutes. During the interictal period, sharp waves and sharp-wave complexes were observed frequently at right parietal and posterior temporal lobes. The venous injection of diazepam (10 mg) normalized EEG quickly. When consciousness loss, especially fluctuating, was observed in the patients of MELAS, complex partial status epilepticus should be considered.

Adult↗
PubMed2001

[A patient with neuroborreliosis presenting gadolinium-enhanced MRI lesions in bilateral facial nerves].

We report a 33-year-old man with bilateral facial paralysis due to neuroborreliosis. About three weeks after rhinorrhea and fever lasting four days, he noticed fatigue in the legs and paresthesia in all four extremities. Another week later, he developed paresthesia in his tongue and bilateral facial muscle weakness, and was admitted to our hospital. On admission, neurological examination revealed moderate bilateral facial muscle weakness, mild paresthesia in the tongue and four extremities, and decreased Achilles tendon reflex bilaterally. Mild pleocytosis and increased protein were found in the cerebrospinal fluid (CSF). IgM antibodies that reacted with the antigens of Borrelia garinii and Borrelia afzelii were found in his serum. Clinically and serologically, he was thus diagnosed as having neuroborreliosis. Brain MRI revealed gadolinium-enhanced lesions of the bilateral facial nerves in the facial nerve canal portion. After three weeks of treatment with 100 mg/day doxycycline and 2 g/day ceftriaxone sodium, his symptoms and CSF abnormalities were rapidly improved. Although facial nerve paralysis is a major symptom of neuroborreliosis, the present report is the first to detect the inflammatory lesions of the facial nerves in the facial nerve canal portion by MRI.

Adult↗
PubMed2000

A new member of the HCO3(-) transporter superfamily is an apical anion exchanger of beta-intercalated cells in the kidney.

The kidneys play pivotal roles in acid-base homeostasis, and the acid-secreting (alpha-type) and bicarbonate-secreting (beta-type) intercalated cells in the collecting ducts are major sites for the final modulation of urinary acid secretion. Since the H(+)-ATPase and anion exchanger activities in these two types of intercalated cells exhibit opposite polarities, it has been suggested that the alpha- and beta-intercalated cells are interchangeable via a cell polarity change. Immunohistological studies, however, have failed to confirm that the apical anion exchanger of beta-intercalated cells is the band 3 protein localized to the basolateral membrane of alpha-intercalated cells. In the present study, we show the evidence that a novel member of the anion exchanger and sodium bicarbonate cotransporter superfamily is an apical anion exchanger of beta-intercalated cells. Cloned cDNA from the beta-intercalated cells shows about 30% homology with anion exchanger types 1-3, and functional expression of this protein in COS-7 cells and Xenopus oocytes showed sodium-independent and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid-insensitive anion exchanger activity. Furthermore, immunohistological studies revealed that this novel anion exchanger is present on the apical membrane of beta-intercalated cells, although some beta-intercalated cells were negative for AE4 staining. We conclude that our newly cloned transporter is an apical anion exchanger of the beta-intercalated cells, whereas our data do not exclude the possibility that there may be another form of anion exchanger in these cells.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed2000

Simulation method of colloidal suspensions with hydrodynamic interactions: fluid particle dynamics

We develop a new simulation method of colloidal suspensions, which we call a "fluid particle dynamics" (FPD) method. This FPD method, which treats a colloid as a fluid particle, removes the difficulties stemming from a solid-fluid boundary condition in the treatment of hydrodynamic interactions between the particles. The importance of interparticle hydrodynamic interactions in the aggregation process of colloidal particles is demonstrated as an example. This method can be applied to a wide range of problems in colloidal science.

Journal Article↗
PubMed2000

Role of p53 in DNA strand break-induced apoptosis in organotypic slice culture from the mouse cerebellum.

Apoptosis occurs not only in mitotic cells but also in postmitotic neuronal cells. We previously suggested that the tumor suppressor gene p53 is required for DNA strand break-induced apoptosis in dissociated culture of cerebellar granule neurons. In this study, we examined the role of p53 in apoptosis using organotypic slice culture of cerebellum from p53 null and wild-type mice. Exposure to bleomycin significantly increased the numbers of TUNEL-, p53-, and c-Jun-positive neurons in the wild-type mouse cerebellar internal granular layer (IGL) and Purkinje cell layer (PL). However, in p53-deficient mice, these responses were not observed. These results are consistent with our previous observations in dissociated neuronal culture showing that the amount of c-Jun protein increases significantly after addition of bleomycin in p53 wild-type cerebellar granule cells. The results presented here also indicate that p53 is involved in DNA strand break-induced apoptosis of fully postmitotic central nervous system neurons and suggest that c-Jun expression occurs downstream of p53 expression.

Animals↗
PubMed2000

Developmental changes in mitochondrial activity and energy metabolism in fetal and neonatal rat brain.

Experiments were undertaken to investigate mitochondrial activity and energy metabolism in the developing rat brain from the late fetal stage to the neonatal stage. Samples of cerebral cortical tissue were obtained from fetuses at 14, 16, 18, and 20 days of gestation, and from pups at 1 h, 1 day and 7 days after birth. Mitochondrial respiration was measured polarographically using homogenates. Fetal and neonatal brains were frozen in situ and fluorometric enzymatic techniques were used for the analysis of ATP, ADP, AMP, and lactate. In the fetal brain, there was a gradual increase in stimulated (+ADP) and uncoupled respiratory rates using glutamate and malate as substrates, from 14 days to 20 days of gestation, together with a moderate increase in ATP concentration and in the sum total of adenine nucleotides, and a significant decrease in lactate. Since non-stimulated (-ADP) respiratory rates did not change with increasing gestational age, the respiratory control ratio appeared to increase over the same period. An increase in mitochondrial activity was more pronounced immediately after birth, together with a marked increase in ATP concentration and in the sum total of adenine nucleotides. The highest rate of mitochondrial respiration was observed in 1-hour-old pups. These results indicate that, in the rat brain, there is maturation of oxidative metabolism in mitochondria that is initiated in late gestation. Acceleration in mitochondrial respiration occurs immediately after birth in order to maintain high-energy phosphate levels, and this may be crucial for the successful outcome of the newborn.

Adenosine Diphosphate↗
PubMed2000

Expression of a subset of the Arabidopsis Cys(2)/His(2)-type zinc-finger protein gene family under water stress.

The genes encoding Cys(2)/His(2)-type zinc-finger proteins constitute a large family in higher plants. To elucidate the functional roles of these types of protein, four different members of the gene family were cloned from Arabidopsis by PCR-aided methods. One was identical to the already reported gene STZ/ZAT10 and three were as yet unidentified genes, then designated AZF1 (Arabidopsis zinc-finger protein 1), AZF2 and AZF3. The AZF- and STZ-encoded proteins contain two canonical Cys(2)/His(2)-type zinc-finger motifs, separated by a long spacer. Three conserved regions, named B-box, L-box, and DNL-box, were also recognized outside the zinc-finger motifs, as in other members of the two-fingered Cys(2)/His(2)-type zinc-finger protein family. These four genes were positioned on the same branch of a phylogenetic tree constructed based on the zinc-finger motif sequences, suggesting their structural and functional relationship. RNA blot analysis showed that all four genes were mainly expressed in roots and at different levels in other organs. Expression of the four genes responded to water stress. High-salt treatment resulted in elevated levels of expression of all of these genes. Low-temperature treatment increased the expression levels of AZF1, AZF3, and STZ, but not AZF2. Only AZF2 expression was strongly induced by ABA treatment, where the time course of the induction was similar to that caused by high salinity. In situ localization showed that AZF2 mRNA accumulated in the elongation zone of the roots under the salt-stress condition. These results suggest that AZF1, AZF2, AZF3, and STZ are all involved in the water-stress response in an ABA-dependent or -independent pathway to regulate downstream genes.

Abscisic Acid↗