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S Ishihara

Publications and source records attributed to S Ishihara.

At least 109 records · Page 6Linked to original sources
PubMed2000

[Thallium-201 single photon emission tomography of intracranial angiomas].

We herein describe thallium-201 single photon emission tomography (T1-201 SPECT) findings in three cases with intracranial angioma. One of the lesions which was associated with chronic encapsulated intracerebral hematoma showed moderate accumulation of T1-201, but, others demonstrated no accumulation. The usefulness and limitations of T1-201 SPECT in differential diagnosis of intracranial mass lesions are discussed.

Adult↗
PubMed2000

Two cases showing clonal progression with full evolution from aplastic anemia-paroxysmal nocturnal hemoglobinuria syndrome to myelodysplastic syndromes and leukemia.

We report 2 paroxysmal nocturnal hemoglobinuria (PNH) patients who were initially diagnosed with aplastic anemia and sequentially developed PNH, myelodysplastic syndromes (MDS), and leukemia. Flow cytometry and cytogenetic analysis showed the initial appearance and expansion of PNH clones, gradual replacement of PNH clones by MDS clones with monosomy 7, and then expansion of MDS clones or their subclones with additional chromosomal abnormalities. In relation to these developments, expression increased of the Wilms' tumor gene WT1, a marker for leukemic progression. These patients not only shared bone marrow failure but also might have harbored a hematopoietic environment favorable for the emergence of abnormal clones leading to leukemogenesis.

Adult↗
PubMed2000

Hypersensitivity to mosquito bites is not an allergic disease, but an Epstein-Barr virus-associated lymphoproliferative disease.

Recently, we showed that 5 cases of hypersensitivity to mosquito bites (HMB) concealed the clonal lymphoproliferation of Epstein-Barr viral (EBV) DNA-positive natural killer (NK) cells. Although the symptoms of HMB have been supposed to derive from Arthus phenomenon, it has become apparent that this unique disorder has the potential to develop into so-called malignant histiocytosis (MH) or related disorders. Accordingly, the criteria for MH have been changed, and a newer diagnostic name, hemophagocytic syndrome, has been described as being associated with viral infection or leukemia/lymphoma. We previously reported that biopsy specimens taken from skin lesions demonstrated infiltration of lymphocytes bearing the phenotype of NK cells. In this study, we found that skin lesions exhibited infiltration of atypical lymphocytes around the small vessels, resembling angiocentric lymphoma, and that these infiltrating cells were positive for EBER-1 by in situ hybridization. These findings support the concept that HMB is the most important manifestation of a certain type of lymphoproliferative disease that presents with an intense local skin reaction and high fever following mosquito bites, and whose essence is the lymphoproliferation of EBV DNA-positive NK cells.

Adolescent↗
PubMed1999

Normal development of mice and unimpaired cell adhesion/cell motility/actin-based cytoskeleton without compensatory up-regulation of ezrin or radixin in moesin gene knockout.

Ezrin/radixin/moesin (ERM) proteins are general cross-linkers between the plasma membrane and actin filaments. Because their expression is regulated in a tissue-specific manner, each ERM protein has been proposed to have unique functions. On the other hand, experiments at the cellular level and in vitro have suggested their functional redundancy. To assess the possible unique functions of ERM proteins in vivo, the moesin gene located on the X chromosome was disrupted by gene targeting in embryonic stem cells. Male mice hemizygous for the mutation as well as homozygous females were completely devoid of moesin but developed normally and were fertile, with no obvious histological abnormalities in any of the tissues examined. In the tissues of the mutant mice, moesin completely disappeared without affecting the expression levels or subcellular distribution of ezrin and radixin. Also, in platelets, fibroblasts, and mast cells isolated from moesin-deficient mice, targeted disruption of the moesin gene did not affect their ERM-dependent functions, i.e. platelet aggregation, stress fiber/focal contact formation of fibroblasts, and microvillar formation of mast cells, without compensatory up-regulation of ezrin or radixin. These findings favor the notion that ERM proteins are functionally redundant at the cellular as well as the whole body level.

Actins↗
PubMed1999

CD8(+)NKR-P1A (+)T cells preferentially accumulate in human liver.

A unique subset of T cells that co-express NKR-P1, which is a lectin type of NK receptor and is thought to have a major role in triggering NK activity, has been identified. In mice, NK1.1 (mouse NKR-P1C)(+) T cells, called NKT cells, preferentially accumulate in the liver and bone marrow. They predominantly use invariant Valpha14 chain TCR and phenotypically are CD4(+)CD8(-) or CD4(-)CD8(-) T cells. In this study, we analyzed, phenotypically and functionally, the NKR-P1A (analogue of murine NKR-P1C)(+) T cells resident in the human liver. Here, we show that in complete contrast to the NKT cells in the mouse liver, the majority of NKR-P1A(+) T cells in the human liver are CD8(+) and their TCR repertoire is not skewed to Valpha24 TCR, the homologue of murine Valpha14 TCR. Almost all of the NKR-P1A(+) T cells in the human liver expressed CD69, suggesting that they were activated. Furthermore, the NKR-P1A(+) T cells in the human liver exhibited strong cytotoxicity against a variety of tumor cell lines including K562, Molt4 and some colonic adenocarcinoma cell lines.

Adenocarcinoma↗
PubMed1999

Melanotic neuroectodermal tumour of infancy at the anterior fontanelle.

We describe a 4-month-old girl presenting with a melanotic neuroectodermal tumour of infancy at the anterior fontanelle. According to the neuroimaging findings, this tumour was found to lie epidurally, adherent to the dura mater, with thickening of the adjacent frontal bone. The tumour was dense on CT, while MRI showed a major part of the tumour to be isointense with cerebral cortex on both T1- and T2-weighted images. The neuroimaging and clinical features are briefly discussed.

Cerebral Cortex↗
PubMed1999

Histological indications of a favorable prognosis with far-advanced gastric carcinomas after preoperative chemotherapy.

PURPOSE: Although preoperative chemotherapy for advanced gastric cancer is now commonly applied with favorable results, convincing evidence for life prolongation and predictive markers for a good prognosis are both lacking. We report here 5 cases that have shown a distinct positive effect of preoperative chemotherapy together with the results of a precise histological examination of materials indicating features predicting a favorable outcome. PATIENTS AND METHODS: A total of 18 patients with a far-advanced gastric carcinoma subjected to gastrectomy after FLEP (5-fluorouracil, leucovorin, etoposide, cisplatin) in the Cancer Institute Hospital of the Japanese Foundation for Cancer Research, Tokyo, could be divided into two distinct groups: 5 surviving over 5 years (group A) and 13 who died within 13 months (group B). Histological features (subtypes) of the carcinomas and chemotherapeutic effects were studied with reference to biopsy materials and resected stomachs and lymph nodes. RESULTS: In group A, 3 of 5 patients had solid-type poorly differentiated adenocarcinomas. In contrast, in group B, 9 had tubular adenocarcinomas (well or moderately differentiated) and 3 non-solid or diffuse-type poorly differentiated adenocarcinomas and there was only one solid-type tumor. In group A, remarkable therapeutic effects were apparent histologically in 4 of the 5 patients with almost complete disappearance of cancer cells from metastases in lymph nodes, whereas no such changes were evident in group B. CONCLUSION: FLEP is distinctly beneficial for certain types of advanced gastric carcinoma, especially solid-type poorly differentiated adenocarcinomas, and favorable results can be predicted, to a certain extent, on the basis of findings for the material resected after chemotherapy.

Adenocarcinoma↗
PubMed1999

Müllerian duct cyst extending into the abdomen.

Müllerian duct cysts occupying the pelvic/abdominal region are rare. We describe a müllerian duct cyst extending into the lower abdomen in a 47-year-old man complaining of urinary retention. We removed the cyst through a suprapubic retrovesical approach. No malignancy was found in the surgical specimen.

Abdomen↗
PubMed1999

The cyclin-dependent kinase inhibitor p27 as a prognostic factor in advanced non-small cell lung cancer: its immunohistochemical evaluation using biopsy specimens.

The expression of p27, which is known as a cyclin-dependent kinase inhibitor, on surgically resected specimens has considerable value for the prognosis of non-small cell lung cancer (NSCLC) patients. We immunohistochemically investigated the expression of the p27 protein in the biopsy specimens taken from 69 advanced NSCLC patients and assessed its clinical value. There was no significant correlation between p27 positivity and clinical parameters, including sex, age, histological type, clinical stage, smoking index and performance status. Furthermore, p27 positivity was not associated with response to chemotherapy. However, the Kaplan-Meier curve demonstrated that low p27 expression was significantly related to poor prognosis (P = 0.0019, by the log-rank test). Using multivariate analysis, p27, age and serum total protein level were found to be the independent prognostic parameters. The p27 positivity in the biopsy specimens of advanced NSCLC appears to be a useful prognostic marker.

Aged↗
PubMed1999

Growth inhibitory effects of somatostatin on human leukemia cell lines mediated by somatostatin receptor subtype 1.

Reverse transcription polymerase chain reaction analysis revealed that only somatostatin receptor (SSTR) 1 mRNA was expressed in Ball-1 B-, Jurkat T-, and HL60 leukemia cell lines. In contrast, human normal mononuclear cells expressed the mRNA of all five subtypes of SSTR, although the expression level of SSTR1 was the highest. A binding study, revealed that [125I]-somatostatin bound specifically to HL60 cells and this binding was inhibited concentration-dependently by unlabeled somatostatin (SS). A [3H]thymidine incorporation study showed that SS significantly and concentration-dependently inhibited HL60 and BALL-1 leukemia cell growth. Furthermore, this inhibition of leukemia cell growth was associated with reduces c-fos gene expression. These data indicate that leukemia cells express SSTR1 and SS reduce c-fos gene expression with resultant suppression of leukemia cell growth, possibly mediated by the SSTRI.

Cell Division↗
PubMed1999

Utility of colorimetric end-tidal carbon dioxide detector for monitoring during prehospital cardiopulmonary resuscitation.

The purpose of this study was to evaluate a colorimetric end-tidal CO2 (ETCO2) detector (EASY CAP) as a monitor during prehospital cardiopulmonary resuscitation (CPR) without tracheal intubation. This detector was used for 121 patients during CPR with a laryngeal mask airway or face mask by authorized emergency lifesaving technicians. At 7 to 15 minutes after the initiation of CPR, ETCO was <0.5% in 30 cases (group A), 0.5% to 2.0% in 46 cases (group B) and >2.0% in 45 cases (group C). The rate of return of spontaneous circulation was 17% in group A, 24% in group B, and 48% in group C (groups A v C, P < .01). There was a significant difference in the rate of hospital admission between groups A and C. The ETCO2 value may be useful for monitoring during prehospital CPR with a laryngeal mask airway or face mask.

Adult↗
PubMed1999

Adequacy of the new guidelines on clinical evaluation of drug efficacy in acute uncomplicated cystitis.

The adequacy of the newly revised criteria for the evaluation of clinical efficacy of antimicrobial agents in acute uncomplicated cystitis harmonized to the IDSA/FDA guidelines was studied. Low bacterial counts were significantly more frequently found in midstream urine than in catheter urine. Non-uropathogens were isolated with significantly higher frequency from patients with bacteriuria of 10(3) colony forming units (cfu)/ml than from patients with higher bacterial counts. It is important to exclude non-uropathogens when patients with bacteriuria of 10(3) cfu/ml are included in the study. Although the clinical failure rate was very low in patients with eradication of the pathogen, the clinical cure rate was only 67% in patients with microbiological failure. Microbiological and clinical outcomes coincided in 93% of the patients. However, the coincidence rate was lower when the eradication rate was low.

Acute Disease↗
PubMed1999

Inhibition of haematogenous metastasis of colon cancer in mice by a selective COX-2 inhibitor, JTE-522.

It is proposed that non-steroidal anti-inflammatory drugs (NSAIDs) reduce colorectal tumorigenesis by inhibition of cyclooxygenase (COX). COX is a key enzyme in the conversion of arachidonic acid to prostaglandins and two isoforms of COX have been characterized, COX-1 and COX-2. Multiple studies have shown that COX-2 is expressed at high levels in colorectal tumours and play a role in colorectal tumorigenesis. Recently it has been reported that selective inhibition of COX-2 inhibits colon cancer cell growth. In this study we investigated the effect of a selective COX-2 inhibitor (JTE-522) on haematogenous metastasis of colon cancer. For this purpose, we selected a murine colon cancer cell line, colon-26, that constitutively expresses the COX-2 protein. The subclone P expressed a high level of COX-2 and the subclone 5 expressed a low level. The colon-26 subclones were injected into the tail vein of BALB/c mice. JTE-522 was given intraperitoneally every day from the day prior to cancer cell injection, and the mice were sacrificed 16 days after cell injection. Lung metastases were compared between groups with and without JTE-522. In the mice injected with subclone P, the number of lung metastatic nodules was significantly reduced in the treated group. However, in the mice injected with subclone 5, there was little difference between the control and the treated groups. These results indicate that there may be a direct link between inhibition of haematogenous metastasis of colon cancer and selective inhibition of COX-2, and that selective COX-2 inhibitors may be a novel class of therapeutic agents not only for colorectal tumorigenesis but also for haematogenous metastasis of colon cancer.

Animals↗
PubMed1999

Prevalence of non-ulcer dyspepsia in the Japanese population.

BACKGROUND: Non-ulcer dyspepsia (NUD) is one of the most frequently encountered disorders in general practice in Western countries. The prevalence of this disorder in the Japanese, however, has not been fully investigated. This study is designed to clarify the characteristics and prevalence of dyspepsia in the Japanese. METHODS: The subjects were 1139 people who visited our institutes for their annual medical check up for gastric cancers. After routine medical examination, all subjects were asked standardized questions in order to check for the presence of any symptoms suggesting dyspepsia. RESULTS: The results of the study showed that dysmotility-like dyspepsia, characterized by the presence of nausea, fullness and early satiety, is the most frequently observed dyspepsia in Japanese and that this type of dyspepsia decreases with age. Ulcer-like dyspepsia, which is the major type of dyspepsia in Western countries, is the least frequently experienced dyspepsia in the Japanese. CONCLUSIONS: This study clarified that NUD is also one of the most prevalent disorders in the Japanese, although its characteristics may be somewhat different from those in Western countries.

Adult↗
PubMed1999

Clinical evaluation of the effect of percutaneous transluminal angioplasty and intra-arterial papaverine infusion for the treatment of vasospasm following aneurysmal subarachnoid hemorrhage.

The clinical efficacy of percutaneous transluminal angioplasty and intra-arterial papaverine infusion for treatment of vasospasm following subarachnoid hemorrhage was investigated. Between 1990 and 1993, 84 patients were treated for cerebral vasospasm in National Defense Medical College Hospital. Angioplasty was performed for asymptomatic vasospasm in 18 patients and for symptomatic vasospasm in 12 patients. Intra-arterial papaverine infusion was performed for asymptomatic vasospasm in 10 patients and for symptomatic vasospasm in four patients. The other 40 patients were treated with standard conservative therapy including hypervolemic and hypertensive hemodilution. The outcomes of these patients were analyzed using the Glasgow Outcome Scale. The outcome tended to be better for patients treated with angioplasty, but not for those treated with papaverine infusion, than for those treated conservatively. Recurrence of vasospasm was more frequent after papaverine infusion than after angioplasty. Undesirable complications such as abrupt development of unconsciousness were experienced during papaverine infusion but not during angioplasty. We conclude that percutaneous transluminal angioplasty is superior to intra-arterial papaverine infusion for prevention and treatment of vasospasm following aneurysmal subarachnoid hemorrhage.

Angioplasty, Balloon↗
PubMed1999

Predictive factors for metachronous recurrence of early gastric cancer after endoscopic treatment.

Since endoscopic treatment has been evaluated and become established as treatment for early gastric cancer, metachronous recurrence has become a major problem. In this report, predictive factors for recurrence were studied using the Kaplan-Meier method and Cox's proportional hazards regression model in 76 patients who received endoscopic treatment. There were 48 men and 28 women age 69.6 +/- 8.3 years (mean +/- standard deviation), 5 of whom had synchronous multiple lesions and 71 who had a single lesion found during the initial endoscopic treatment. In all patients, periodic follow-ups were performed by endoscopy for more than 2 years after treatment. Helicobacter pylori infection was assessed in 55 of the 76 patients, and proved positive in 43 and negative in 12. Metachronous recurrence was detected significantly more frequently in patients whose synchronous multiple lesions were found during the initial treatment. In addition, age affected the recurrence positively. However, gender and H. pylori infection had no significant relationship with metachronous recurrence.

Adenocarcinoma↗
PubMed1999

Effects of long-term hemofiltration on circulating mediators and superoxide production during continuous endotoxin administration.

BACKGROUND: The purpose of this study was to test whether continuous hemofiltration eliminates cytokines and eicosanoids, or stimulates granulocyte function. METHODS: Nineteen pigs were divided into a control group (n = 7), a hemofiltration group (n = 7), and an extracorporeal circuit only group (n = 5). All animals received the same amount of intravenous endotoxin and resuscitation fluid. Zero-balanced hemofiltration was started 30 minutes after initiation of endotoxemia and continued throughout the experiment. Plasma endotoxin, tumor necrosis factor-alpha, eicosanoids, superoxide production, and other physiologic parameters were measured before challenge and at scheduled intervals thereafter. RESULTS: Eicosanoids were filtered but plasma concentrations were not reduced. Tumor necrosis factor-alpha was not filtered or adsorbed. There were no significant differences between groups in any measured parameters. CONCLUSION: Continuous hemofiltration could not efficiently remove tumor necrosis factor-alpha or eicosanoids. Also, continuous hemofiltration did not stimulate production of the proinflammatory mediators measured, nor improve respiratory distress.

6-Ketoprostaglandin F1 alpha↗