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Biomedical subjects

K Takeuchi

Publications and source records attributed to K Takeuchi.

At least 235 records · Page 13Linked to original sources
PubMed2000

Thrombopoietin enhances neutrophil production by bone marrow hematopoietic progenitors with the aid of stem cell factor in congenital neutropenia.

We examined the effects of granulocyte colony-stimulating factor (G-CSF), stem cell factor (SCF), and thrombopoietin (TPO), alone or in combination, on the generation of neutrophils by bone marrow (BM) cells from three patients with severe congenital neutropenia (SCN) through the use of a serum-deprived liquid culture system. Synergistic effects of G-CSF and SCF on the neutrophil production by BM CD34+CD38+c-kit+ cells were observed in SCN patients as well as in normal controls. The addition of TPO to the culture containing G-CSF and SCF further augmented the growth of neutrophils in the two groups. Single-cell culture experiments revealed that the three-factor combination caused increases in both the number and size of neutrophil colonies compared with G-CSF + SCF in normal BM cells, whereas only a significant increment in the colony size was observed in SCN patients. Even in the presence of SCF or SCF + TPO, the concentrations of G-CSF necessary for the substantial production of neutrophils by CD34+CD38+c-kit+ cells were higher in two patients compared with the levels obtained by normal control cells. In addition, TPO did not accelerate the maturation of neutrophilic cells supported by G-CSF + SCF. When BM CD34+CD38-c-kit+ cells were targeted, the addition of TPO to the culture containing G-CSF and SCF was required for significant neutrophil colony growth in the two groups. These results suggest that TPO enhances the G-CSF-dependent neutrophil production with the aid of SCF in this disorder.

ADP-ribosyl Cyclase↗
PubMed2000

[Rheumatoid vasculitis with multiple intestinal ulcerations: report of a case].

Rheumatoid vasculitis is a relatively uncommon complication of rheumatoid arthritis (RA). It shows wide variety of extra-articular features including skin and neurologic involvement, but rarely shows gastrointestinal involvement. We describe a 79-old-man of rheumatoid vasculitis manifesting as small bowel multiple ulcerations accompanied by perforation of the descending colon diverticulum. The patient was admitted to our hospital with rectal bleeding and severe anemia. He had had rheumatoid arthritis for more than 10 years with treatment of non-steroidal anti-inflammatory drugs (NSAIDs) and low-dose prednisone. Upper endoscopy or colonoscopy revealed no evidence of bleeding. Suddenly he developed cramping abdominal pain, and emergency operation was performed. Segments of the descending colon and small bowel were resected to reveal perforation of the descending diverticulum and severe multiple ulcer of small bowel. The pathological examination showed multiple ulcerations of the small intestine was caused by vasculitis.

Aged↗
PubMed2000

"Malignant struma ovarii" with peritoneal metastasis: report of two cases.

Malignant struma ovarii with metastasis in an extremely rare form of ovarian carcinoma. We describe two cases of malignant struma ovarii that demonstrated widespread peritoneal metastases. In the second case described here, furthermore, the tumor recurred II years later in the contralateral ovary and omentum, while the primary tumor previously was pure struma ovarii with no evidence of metastasis. Although thyroid tumors themselves are characterized by a long latent interval, patients with benign thyroid tissue arising in nonthyroidal organs with or even without dissemination should be managed with caution and need appropriate long-term follow-up after the initial surgery.

Adult↗
PubMed2000

Liposarcoma of the uterine cervix: case report.

A case of primary liposarcoma of the cervix is described in a 49-year-old woman with a fungating cervical mass which was diagnosed as liposarcoma on the basis of cytologic features and the intracellular lipids. Most of the adipocytes and vacuolated lipoblasts were positive for S- 100 protein. The mass was well circumscribed and limited to the superficial cervical stroma. A total abdominal hysterectomy and bilateral salpingo-oophorectomy with pelvic lymphadenectomy was performed. There was no clinical evidence of metastasis two years after the operation.

Female↗
PubMed2000

Successful resection of superior mesenteric artery aneurysm. A case report and review of the literature.

Superior mesenteric artery aneurysms are rare, comprising only 8% of all visceral artery aneurysms. Aneurysms at the site are very susceptible to rupture, irrespective of size and may be difficult to manage even in the case of elective surgery. In the absence of serious complicating factors, the treatment of choice is excision of the aneurysm and reconstruction of the artery, if necessary, to maintain patency. We report the successful resection of an aneurysm and the subsequent reconstruction of the superior mesenteric artery which was directly anastomosed to the aorta after resection of an aneurysm.

Anastomosis, Surgical↗
PubMed2000

[Clinical efficacy of immunotherapy with house dust in the patients with perennial nasal allergy].

We tried to elucidate the relation of age and severity with the efficacy of immunotherapy. The subjects included 51 patients with perennial allergic rhinitis who had immunotherapy for more than a year. Symptom scores, serum total IgE levels, Dermatophagoides pteronyssinus specific IgE, and peripheral blood eosinophils counts were evaluated before, half a year, one year and two years after the onset of immunotherapy. 64% of the children's group and 69% of the adults' group of patients showed significant improvement in their nasal symptoms, showing that age is not a factor influencing the efficacy of immunotherapy. The severity of the disease influenced the clinical efficacy; the more severe the disease, the poorer the efficacy of the immunotherapy. Periphipheral blood eosinophils counts gradually decreased after the onset of immunotherapy. High eosinophil counts before immunotherapy predicted poor efficacy of the immunotherapy.

Adolescent↗
PubMed2000

Multivariate analysis of long-term results after an axillobifemoral and aortobifemoral bypass in patients with aortoiliac occlusive disease.

BACKGROUND: Controversy still remains regarding the long-term results and indications for axillofemoral bypass (AxFB). A comparison of axillobifemoral bypass (AxBFB) and aortobifemoral bypass (ABFB) was thus conducted to determine whether AxFB is an acceptable alternative vascular procedure to anatomic bypass for high-risk patients. METHODS: Sixty-three patients who underwent a total of 25 AxBFBs and 38 ABFBs for aortoiliac occlusive disease were reviewed retrospectively, and both univariate and multivarate analyses were perfomed. RESULTS: The overall survival was 82.8% at five years. A univariate analysis revealed significantly lower survival rates for patients with limb-threatening ischemia, coronary disease, and cerebrovascular disease. A multivariate analysis disclosed no significant factors influencing survival rates. The overall primary patency was 79.8% at five years. The primary patency rates for AxBFB (67.7% at five years) were significantly lower than for ABFB (88.5% at five years) based on a univariate analysis (p=0.0045). In addition, the secondary patency rates for AxBFB (80.3% at five years) were significantly lower than for ABFB (96.5% at five years, p=0.0025). A multivariate analysis disclosed significantly lower primary patency rates for grafts with a higher angiographic outflow score and simultaneous infrainguinal reconstructive procedures, but the differences between AxBFB and ABFB were not significant. CONCLUSIONS: The survival and primary patency for the AxBFB group were both inferior to the ABFB group, however a multivarate analysis disclosed no significant differences between the two groups. Poor femoral run-off and the presence of synchronous infrainguinal reconstructive procedures significantly affected graft patency, and these factors modulated the patency of AxBFB. AxFB for aortoiliac occlusive disease is therefore considered to be an acceptable procedure in appropriately selected patients.

Adult↗
PubMed2000

Preoperative cerebrovascular screening before cardiovascular surgery in a high risk area of cerebrovascular events in Japan.

BACKGROUND: Cerebrovascular disease and cervical artery diseases are potentially treatable conditions that are associated with an increased incidence of stroke after cardiac surgery. This prospective study was designed to determine the prevalence of cerebrovascular diseases in the high risk population of cerebrovascular event including some young patients in Japan and establish the strategy for cardiac surgery of patients with cerebrovascular disease. METHODS: 100 (71 male, 29 female) of 126 consecutive patients undergoing cardiac surgery under cardiopulmonary bypass were screened for the presence of cerebrovascular disease by intra-arterial angiogram. RESULTS: In seven patients angiographic evaluation disclosed some evidence of cerebrovascular disease for 50% or greater stenosis or cerebral aneurysm. Preoperative 99mTc-Hexamethyl propylene amino oxime (99mTc-HMPAO) single emission computed tomography (SPECT) with combination of balloon arterial occlusion test provided detailed information of cerebral ischemic tolerance and reliable decision making for surgical repair of cerebrovascular disease. No deaths were recorded and a small stroke in one patient. CONCLUSIONS: We concluded that cerebrovascular screening in patients with cardiovascular disease may be requested in a high risk population of cerebrovascular events.

Adult↗
PubMed1999

Sequence analysis of a total of three megabases of DNA in two regions of chromosome 8p.

Large-scale sequencing of genomic regions and in silico gene trapping together represent a highly efficient and powerful approach for identifying novel genes. We performed megabase-level sequence analyses of two genomic regions on human chromosome 8p (8p11.2 and 8p22-->p21.3), after covering those segments with sequence-ready contigs composed of 74 cosmids, 14 BACs, and three PAC clones. We determined continuous nucleotide sequences of 1,856,753 bases on 8p11.2 and 1,210,381 bases on 8p22-->p21.3 by combining the shotgun and primer-walking methods. In silico gene trapping identified four novel genes in the 8p11.2 region and, in the 8p22-->p21.3 region, six known genes (PRLTS, PCM1, MTAMR7, HCAT2, HFREP-1 and PHP) and three novel genes. The distribution of Alu and LINE1 repetitive elements and the densities of predicted exons were different in each region, and Alu-rich portions contained more exonic sequences than LINE1-rich areas.

Amino Acid Sequence↗
PubMed1999

EP4 receptor mediation of prostaglandin E2-stimulated mucus secretion by rabbit gastric epithelial cells.

Prostaglandin (PG) E receptors are divided into four subtypes (EP1-EP4). We investigated the EP receptor subtype involved in PGE2-stimulated mucus secretion by rabbit gastric epithelial cells. Northern blot analysis revealed that epithelial cells express EP3 and EP4 receptor mRNAs, but neither EP1 nor EP2 receptor mRNAs were detected. PGE2, 11-deoxy-PGE1 (an EP3/EP4/EP2 agonist) and 16,16-dimethyl-PGE2 (an EP3/EP2/EP4 agonist) concentration-dependently promoted mucus secretion. In contrast, 17-phenyl-PGE2 (an EP3/EP1 agonist), sulprostone (an EP3/EP1 agonist), and butaprost (an EP2 agonist) failed to stimulate secretion. The effective concentrations of PGE2, 11-deoxy-PGE1, and 16,16-dimethyl-PGE2 were associated with their affinities for the EP4 receptor. In addition, PGE2, 11-deoxy-PGE1, and 16,16-dimethyl-PGE2 increased cyclic AMP (cAMP) production, but the other prostanoids had no effect. SQ22536 [9-(tetrahydro-2'-furyl)adenine; an adenylate cyclase inhibitor] inhibited both the increased cAMP production and mucus secretion induced by PGE2, 11-deoxy-PGE1, and 16,16-dimethyl-PGE2. H-89 (N-[2-((p-bromocinnamyl)amino)ethyl]-5-isoquinoline sulfonamide; a protein kinase A inhibitor) also abolished the stimulatory effects of the prostanoids on mucus secretion, but calphostin C (a protein kinase C inhibitor) did not. These results indicate that PGE2 promotes mucus secretion by rabbit gastric epithelial cells, mediated through EP4 receptor stimulation and the subsequent activation of protein kinase A.

16,16-Dimethylprostaglandin E2↗
PubMed1999

Increased cytosolic Ca(2+) concentration in endothelial cells by calmodulin antagonists.

Many functions of endothelial cells are Ca(2+)/calmodulin dependent, whereas the role of calmodulin in the regulation of cytosolic Ca(2+) ([Ca(2+)](i)) remains largely unexplained. In the present study, effects of various calmodulin antagonists on [Ca(2+)](i) were investigated in cultured aortic endothelial cells loaded with the Ca(2+)-sensitive dye fura-2/AM, and were compared with those of calmodulin-dependent protein kinase II (CaM kinase II) inhibitors. The calmodulin antagonists W-7, calmidazolium and fendiline provoked dose-dependent increases in [Ca(2+)](i). However, the CaM kinase II inhibitors KN-93 and lavendustin C had no effect on [Ca(2+)](i). In the absence of extracellular Ca(2+), pretreatment of cells with bradykinin (BK) and thapsigargin completely prevented W-7-stimulated increase in [Ca(2+)](i). Alternatively, pretreatment with W-7 also completely blocked BK- and thapsigargin-stimulated increases in [Ca(2+)](i). The time course of the Ca(2+)-response in W-7 treated cells was identical to that in thapsigargin-treated cells, but not that in BK-stimulated cells, suggesting that calmodulin antagonists could share a common signaling pathway with thapsigargin to increase [Ca(2+)](i) in endothelial cells. These findings indicate that calmodulin is involved in the regulation of [Ca(2+)](i), and may play an important role in the uptake of Ca(2+) to intracellular stores.

Animals↗
PubMed1999

Impaired glucose transporter activity in pressure-overload hypertrophy is an early indicator of progression to failure.

BACKGROUND: Severe hypertrophy and heart failure are important risk factors in cardiac surgery. Early adaptive changes in hypertrophy include increased ventricular mass-to-cavity volume ratio (M/V ratio) and increased dependence on glucose for energy metabolism. However, glucose uptake is decreased in the late stages of hypertrophy when ventricular dilatation and failure are present. We hypothesized that impaired glucose uptake would be evident early in the progression of hypertrophy and associated with the onset of ventricular dilatation. METHODS AND RESULTS: Ten-day-old rabbits underwent banding of the descending aorta. Development of hypertrophy was followed by transthoracic echocardiography to measure left ventricular M/V ratio. Glucose uptake rate, as determined by (31)P-nuclear magnetic resonance spectroscopy measuring 2-deoxyglucose conversion to 2-deoxyglucose-6-phosphate, was measured in isolated perfused hearts obtained from banded rabbits when M/V ratio had increased by 15% from baseline (compensated hypertrophy) and by 30% from baseline (early-decompensated hypertrophy). In age-matched control animals, the rate of glucose uptake was 0.61+/-0.08 micromol x g of wet weight(-1) x 30 min(-1) (mean+/-SEM). With a 15% M/V ratio increase, glucose uptake rate remained at control levels (0.6+/-0.05 micromol x g of wet weight(-1) x 30 min(-1)), compared with hearts with 30% increased M/V ratios, where glucose uptake was significantly lower (0.42+/-0.05 micromol x g of wet weight(-1) x 30 min(-1); P</=0.05). Glucose transporter protein expression was the same in all groups. CONCLUSIONS: Glucose uptake rate is maintained during compensated hypertrophy. However, coinciding with severe hypertrophy, preceding ventricular dilatation, and glucose transporter protein downregulation, glucose uptake is significantly decreased. Because of the increased dependence of the hypertrophied hearts on glucose use, we speculate that this impairment may be a contributing factor in the progression to failure.

Animals↗