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Biomedical subjects

R Ishii

Publications and source records attributed to R Ishii.

At least 37 records · Page 2Linked to original sources
PubMed2001

Elevation of serum pro-gastrin-releasing peptide in patients with medullary thyroid carcinoma and small cell lung carcinoma.

Medullary thyroid carcinoma (MTC) arises from parafollicular or C cells of the thyroid gland and produces a variety of peptides such as calcitonin (CT) and gastrin-releasing peptide (GRP). Here we measured serum levels of pro-gastrin-releasing peptide (Pro-GRP), a more stable precursor of GRP, in 15 patients with MTC (4 males, 11 females) who did not show any clinical or radiologic signs of small cell lung cancer. Serum Pro-GRP levels were elevated in 80% (12/15) patients. Significant correlation was observed between serum Pro-GRP and CT (r = 0.52) and carcinoembryonic antigen (CEA) (r = 0.56). Serum Pro-GRP levels also correlated with tumor size (r = 0.70). Serum Pro-GRP levels also decreased below the cut-off range in one patient after surgical resection. Our data suggest that Pro-GRP, which is considered to be a specific marker for small cell lung carcinoma, seems to be also helpful and additional marker for the diagnosis and monitoring the response to therapy in patients with MTC in addition to calcitonin as the main tumor marker.

Adult↗
PubMed2001

On the sound sources of screech tones radiated from choked circular jets.

The generation mechanism of the screech tone in the helical oscillation mode is mainly investigated using a series of instantaneous schlieren photographs. From the photographs, five evanescent sound sources are observed as prominent points along the jet axis. The sound source for the dominant helical oscillation mode is found to be the second prominent point which moves along a circular orbit in a plane perpendicular to the jet axis and just downstream of the rear edge of the third shock cell. It is shown that the speed of a moving sound source is supersonic and that the Mach cone generated by the moving sound source forms the helical-shaped wave front of the screech tone for the helical oscillation mode of the jet. This idea of the moving sound source is well supported by a measured directionality of the screech tone. Sound sources of the other oscillation modes appearing in the other pressure ratio ranges are also described.

Journal Article↗
PubMed2001

Oscillation modes of supersonic multijets exhausting from very adjacent multiple nozzles.

The oscillation modes of a supersonic circular twin jet and multijet with square configuration where the center-to-center spacing of nozzles was fixed to 1.4 times the nozzle diameter were investigated experimentally. It is found that the twin jet oscillates simultaneously in three different oscillation modes for the pressure ratios of about 4.1. From the acoustical observation, these oscillation modes are identified as one lateral oscillation mode perpendicular to a plane composed of the twin jet axes and two lateral oscillation modes parallel to this plane. For a multijet with a square configuration, only one lateral oscillation mode was observed. In this case, it is observed that when the spacing between two facing sides of the square formed by four jets is stretched, the spacing between the other two sides shrinks and vice versa.

Journal Article↗
PubMed2001

Antiallergic agents from natural sources. 3. Structures and inhibitory effects on nitric oxide production and histamine release of five novel polyacetylene glucosides from Bidens parviflora WILLD.

Five new polyacetylene glucosides, bidensyneosides A1, A2, B, C (1-4), and 3-deoxybidensyneoside B (5), have been isolated from the air-dried whole plant of Bidens parviflora WILLD. The structures were identified based on spectroscopic analysis, physicochemical properties, and application of the modified Mosher method to be 3(R),8(E)-8-decene-4,6-diyne-1,3-diol 1-O-beta-D-glucopyranoside (1), deca-3(R),8(Z) 8-decene-4,6-diyne-1,3-diol 1-O-beta-D-glucopyranoside (2), 3(R)-deca-4,6,8-triyne-1,3-diol 1-O-beta-D-glucopyranoside (3), 3(R),8(E)-8-decene-4,6-diyne-1,3,10-triol 1-O-beta-D-glucopyranoside (4), and 8(E)-8-decene-4,6-diyne-1,10-diol 1-O-beta-D-glucopyranoside (5), respectively. These compounds inhibited nitric oxide (NO) production in lipopolysaccharide and interferon-gamma activated murine macrophages (RAW264.7) and also inhibited histamine release from rat mast cells stimulated by the antigen-antibody reaction.

Acetylene↗
PubMed2001

Thymidine phosphorylase expression is useful in selecting adjuvant chemotherapy for stage III gastric cancer.

Thymidine phosphorylase (TP) is an enzyme which converts doxifluridine (5'-DFUR) to 5-fluorouracil (5-FU). To assess whether TP expression is useful for selecting adjuvant chemotherapy in advanced gastric cancer, we compared effects of oral 5'-DFUR and 5-FU and assessed correlation between drug efficacy and TP expression level. We examined TP expression in 286 patients. TP expression was assessed with immunohistochemical staining. When we compared prognosis in two chemotherapy groups with high TP expression, better survival was observed in 5'-DFUR than in 5-FU group (p=0.0413). Especially in stage III, patients with high TP had better survival in 5'-DFUR than in 5-FU group.

Adult↗
PubMed2001

[A case of infected subdural hematoma due to Campyrobacter fetus].

A 20-year-old male presented fever, nausea and headache 1 week after eating uncooked liver. On admission, it was revealed he had suffered a closed head injury 3 months before without unconsciousness. On admission, computed tomography scan showed a left chronic subdural hematoma. Gd-DTPA magnetic resonance images revealed unusual enhancement of the capsule and linear enhancement of the subarachnoid space. The patient underwent burr hole irrigation and drainage. The culture of the hematoma content showed Campylobacter fetus. Therefore, the diagnose was infected subdural hematoma. A drainage operation and administration of antibiotics were effective. Our case suggests that enhanced magnetic resonance images are useful for diagnosis and follow-up of infected subdural hematoma.

Adult↗
PubMed2000

Somatic mutations of LKB1 and beta-catenin genes in gastrointestinal polyps from patients with Peutz-Jeghers syndrome.

Peutz-Jeghers syndrome (PJS) is characterized by multiple gastrointestinal hamartomatous polyps, mucocutaneous melanin deposition, and increased risk of cancer, mainly in the gastrointestinal tract. We examined mutations of the LKB1, beta-catenin, APC, K-ras, and p53 genes in 27 gastrointestinal hamartomatous polyps from 10 patients in nine PJS families. Of these hamartomatous polyps, one intestinal polyp had an adenomatous lesion, and one gastric polyp contained adenomatous and carcinomatous lesions. Germ-line mutations of the LKB1 gene were detected in six PJS families. Somatic mutations of the LKB1 gene were found in 5 polyps, whereas loss of heterozygosity (LOH) at the LKB1 locus at 19p was seen in 14 other polyps. In adenomatous lesions microdissected from hamartomatous polyps, both beta-catenin mutation and 19p LOH were detected. Furthermore, a carcinomatous lesion in a gastric hamartomatous polyp was found to contain a mutation of the p53 gene and LOH at the p53 locus in addition to LOH at the LKB1 locus and a beta-catenin mutation. K-ras mutations were detected in a few polyps, whereas no APC mutation or 5q LOH was detected in hamartomatous polyps. These results suggest that gastrointestinal hamartomatous polyps in PJS patients develop through inactivation of the LKB1 gene by germ-line mutation plus somatic mutation or LOH of the unaffected LKB1 allele, and that additional mutations of the beta-catenin gene and p53 gene convert hamartomatous polyps into adenomatous and carcinomatous lesions.

AMP-Activated Protein Kinase Kinases↗
PubMed2000

Theta rhythm increases in left superior temporal cortex during auditory hallucinations in schizophrenia: a case report.

Auditory hallucinations (AH), the perception of sounds and voices in the absence of external stimuli, remain a serious problem for a large subgroup of patients with schizophrenia. Functional imaging of brain activity associated with AH is difficult, since the target event is involuntary and its timing cannot be predicted. Prior efforts to image the patterns of cortical activity during AH have yielded conflicting results. In this study, MEG was used to directly image the brain electrophysiological events associated with AH in schizophrenia. We observed an increase in theta rhythm, as sporadic bursts, in the left superior temporal area during the AH states, whereas there was steady theta band activity in the resting state. The present finding suggests strong association of the left superior temporal cortex with the experience of AH in this patient. This is consistent with the hypothesis that AH arises from areas of auditory cortex subserving receptive language processing.

Adult↗
PubMed2000

Cytology of microcystic meningioma in crush preparation.

Microcystic meningioma is a rare variant of meningioma, showing microcystic formations throughout the tumor. To the best of our knowledge, there have been no reports describing cytologic findings of microcystic meningioma. Our case was a 66-yr-old woman with a tumor mass adhered to the dura matter. The crush preparations of a small tissue fragment resected from the mass showed medium- to large-sized, well-cohesive clusters or sheets of uniform tumor cells. The tumor cells did not show a feathering-off pattern. Various-sized cystic spaces were observed within the clusters and sheets. The cytoplasm was relatively abundant, and the nuclear:cytoplasmic ratio was lower than that of classic meningioma. We believe that the cystic spaces within the cell clusters or sheets are characteristic of microcystic meningioma. The cytology of microcystic meningioma seen in our case was similar to that of metastatic adenocarcinoma, but relatively monotonous bland cells, smooth nuclear outline, and inconspicuous nucleoli led us to the diagnosis of meningioma rather than adenocarcinoma.

Aged↗
PubMed2000

Molecular evidence for multicentric development of thyroid carcinomas in patients with familial adenomatous polyposis.

Familial adenomatous polyposis is characterized by multiple colorectal adenomas and an increased incidence of colorectal carcinomas. Patients also develop various extracolonic tumors, of which, thyroid carcinoma is common in young females. The occurrence of multiple carcinomas in one thyroid is frequently observed, although some carcinomas are solitary. To clarify whether each carcinoma develops independently or metastatically spreads from the first one formed, we analyzed the adenomatous polyposis coli (APC) gene mutation in each carcinoma. We found that each carcinoma had a different somatic mutation of the APC gene. This is molecular confirmation for the multicentric development of thyroid carcinomas in familial adenomatous polyposis through biallelic inactivation of the APC gene.

Adenomatous Polyposis Coli↗
PubMed2000

Spontaneous regression of hepatocellular carcinoma and review of literature.

A 68-year-old man presented with multiple hepatocellular carcinoma, which was considered to be unresectable at the first admission in January 1994. Pathological diagnosis was made by biopsy of the one lesion among them. From January 1994 to December 1997, 10 transarterial chemoembolizations and six percutaneous ethanol injection therapies were performed on the tumours in the cirrhotic liver. In February 1998 the tumour situated in the right lobe began to increase in size. The maximum tumour diameter was 6.3 cm measured by computed tomography (CT). In the beginning of May 1998 moderate ascites was present and mild hepatic encephalopathy was noticed. The patient was in the terminal stage of hepatocellular carcinoma and no further treatment was possible at that time. However, serum alpha-fetoprotein and protein induced by vitamin K absence or antagonist II dramatically decreased in June 1998. The CT scan also showed that the tumour had completely regressed without specific treatment. In February 1999 a new biopsy-proven hepatocellular carcinoma, 2 cm in diameter, developed in the lateral segment of the liver. It was well treated by percutaneous ethanol injection therapy. The patient was alive in good condition without any symptoms or tumour recurrence in June 1999. It was concluded that a rare case of spontaneous regression of hepatocellular carcinoma had occurred.

Aged↗
PubMed1999

Serotonergic blockade in the treatment of the cancer anorexia-cachexia syndrome.

BACKGROUND: Imbalanced amino acid diets in animals rapidly produce anorexia and weight loss. Blockade of type 3 serotonergic receptors (5HT(3)) can ameliorate anorexia in this animal model. Imbalanced plasma amino acid levels also have been documented in both animal models and human patients with cancer cachexia. Therefore a trial of the 5HT(3) receptor antagonist, ondansetron, was undertaken in the treatment of patients with cancer cachexia. METHODS: Patients with metastatic cancer who were not undergoing chemotherapy or radiotherapy and who had lost >5% of their body weight were eligible. Baseline physical examination; weight; anthropometric studies; levels of retinol binding protein, albumin, and prealbumin; and skin testing for anergy were obtained. The ability to enjoy food was assessed utilizing a seven-point hedonic category scale for specific foods. Therapy was comprised of oral ondansetron, 8 mg twice a day. RESULTS: Twenty-seven patients were enrolled; all were evaluable for toxicity and 20 patients were evaluable for response. Toxicity of ondansetron was minimal. Patients demonstrated significant weight loss prior to disease entry (mean baseline weight of 76.9 kg vs. 72. 1 kg; P < 0.000002). Patients continued to lose weight on study (Week 0: 72.5 kg vs. Week 4: 71.4 kg; P = 0.027); in addition, there was significant deterioration of midarm circumference and hand grip strength, all of which indicated worsening nutritional status. However, a significant improvement in food enjoyment was noted (P = 0.04). CONCLUSIONS: Although it apparently improved the ability of patients to enjoy food, the blockade of 5HT(3) receptors failed to prevent weight loss in patients with cancer cachexia or alter laboratory parameters of protein nutrition.

Adult↗
PubMed1999

Medial prefrontal cortex generates frontal midline theta rhythm.

Frontal midline theta rhythm (Fm theta) is a distinct theta activity of EEG in the frontal midline area that appears during concentrated performance of mental tasks in normal subjects and reflects focused attentional processing. To tomographically visualize the source current density distributions of Fm theta, we recorded Fm theta by using a 64-channel whole-head MEG system from four healthy subjects, and applied a new analysis method, synthetic aperture magnetometry (SAM), an adaptive beam forming method. Fm theta was observed in the MEG signals over the bilateral frontal regions. SAM analysis showed bilateral medial prefrontal cortices, including anterior cingulate cortex, as the source of Fm theta. This result suggests that focused attention is mainly related to medial prefrontal cortex.

Adult↗
PubMed1999

Propofol does not affect the canine cardiac conduction system under autonomic blockade.

PURPOSE: To determine the effects of propofol on the cardiac conduction system in dogs with pharmacological autonomic blockade. METHODS: In eight mongrel dogs receiving 6 mg.kg-1.hr-1 propofol and vecuronium under pharmacological autonomic blockade with atropine and propranolol the infusion rates of propofol were increased from 6, (baseline), to 12, 18 and 24 mg.kg-1.hr-1 at 60-min intervals. An electrophysiological study assessed sinus rate, sinus node recovery time, corrected sinus node recovery time, intraatrial conduction time, AV nodal effective refractory period, Wenckebach cycle length and AV conduction times. Electrocardiographical variables and arterial pressures were also measured. All measurements were repeated at 30 min after the beginning of each infusion of propofol. RESULTS: Propofol did not produce direct effects on the electrophysiological or electrocardiographical variables at any infusion rates. Heart rates did not change at higher infusion rates in the presence of decreases in arterial pressures. CONCLUSION: Propofol did not affect the cardiac conduction system in the presence of autonomic blockade. Thus, the direct cardiac effects of propofol do not play a causative role in the genesis of propofol-associated bradyarrhythmias.

Anesthetics, Intravenous↗
PubMed1999

Prader-Willi syndrome in a child with XYY.

We report a 26-month-old boy with XYY syndrome, with the complication of Prader-Willi syndrome (PWS) due to uniparental maternal disomy of chromosome 15. To our knowledge, this is the first case of XYY syndrome and PWS. Clinical findings were fully compatible with the diagnostic criteria for PWS. Molecular analysis revealed a maternal heterodisomy of chromosome 15, indicating that non-disjunction of chromosome 15 had occurred at maternal meiosis I, and that the non-disjunction of chromosome Y and of chromosome 15 had occurred independently.

Child, Preschool↗
PubMed1999

[Induction of protective immunity for Bordetella pertussis by nasal inoculation of pertussis vaccine in mice].

Although nasal vaccination has emerged as an interesting alternative to intramuscular or oral vaccination, knowledge is scarce about the immune responses after such immunization. In the present study, we inoculated purified Pertussis Toxin (PT) and Filamentous Haemagglutinin (FHA) with or without adjuvant (kayexalate), or Diphtheria acellular Pertussis Tetanus (DaPT) combined vaccine to mice intranasally three times every four weeks to investigate the references of the immunoresponses between nasal and intramuscular vaccination. The levels of pertussis specific serum IgG antibodies (Abs) and secretory IgA Abs in the nasal wash were measured by ELISA, and cytotoxic T cell activities were examined by proliferative response, and compared with the result from intramuscular inoculation. We also studied the efficacy of adjuvant in the nasal vaccination. The intramuscular inoculation of pertussis vaccine induced serum IgG antibodies and cellular immunity against PT and FHA, but did not induce local IgA antibodies. On the other hand, the nasal inoculation induced both serum and local antibody responses. Moreover, it also induced significant cellular immunity to pertussis antigen. In nasal vaccination, the inoculation with adjuvant was superior to inoculation without adjuvant for the induction of both humoral and cellular immunity.

Animals↗