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S Koike

Publications and source records attributed to S Koike.

At least 55 records · Page 3Linked to original sources
PubMed1998

Nitric oxide synthase and NADPH-diaphorase in neurons of the rat, dog and guinea pig nodose ganglia.

Localization of nitric oxide synthase (NOS) in the nodose ganglia of the dog, rat and guinea pig was investigated. A double-staining technique of NOS immunohistochemistry and NADPH-diaphorase (NADPHd) histochemistry was used; then the ratio of NADPHd-positive and NOS-positive cells to the total cells was calculated. The distribution of positive cells within the canine nodose ganglion was also investigated. NADPHd-positive neurons were detected in all the ganglia. Three intensities of reactivity to NADPHd histochemistry (strong, weak or negative) were detected in the neurons of all three species. There were more cells that stained strongly for NADPHd in the rat, but fewer in the dog and guinea pig, indicating that a species difference may exist. NADPHd-positive neurons were less abundant in the rostral third of the canine nodose ganglion than in the middle or caudal thirds. NADPHd reactivity was completely co-localized to the cells that demonstrated neuronal NOS immunoreactivity in the canine nodose ganglion. Thus, NADPHd histochemical reactivity may be a reliable marker of NOS in the nodose ganglion.

Animals↗
PubMed1998

Mouse skin reactions following fractionated irradiation with carbon ions.

PURPOSE: Skin reactions in the mouse leg following various daily doses given with 290 MeV/u carbon ions were investigated. MATERIALS AND METHODS: Seven different LET (linear energy transfer) values ranging from 14 to 100keV/microm were selected. The fractionation schedules were 1-, 2-, 4- and 8-daily fractions. The isoeffect doses to produce moist desquamation on the dose-response curves were calculated with 95% confidence limits. RESULTS: The isoeffect doses for carbon ions of 14 and 20 keV/microm increased with an increase in the number of fractions up to 4 fractions, but became constant when the number of fractions further increased to 8 fractions. This leveling off in isoeffect dose was more prominent for 40 keV/microm. Recovered dose per fraction was largest for 2 fractions of the 14keV/microm carbon beam. The isoeffect doses for 50, 60, 80 and 100keV/microm consistently increased with an increase in the number of fractions and did not show saturation up to 8 fractions. RBE (relative biological effectiveness) increased linearly with LET for all fractionation schedules. CONCLUSIONS: These results suggest that daily fractionation with carbon ions could spare radiation damage in patients, and that changes the fractionation schedule affect clinical outcome.

Animals↗
PubMed1998

Synchronous gastric tumors associated with esophageal cancer: a retrospective study of twenty-four patients.

OBJECTIVES: Synchronous gastric tumors (including benign and secondary tumors) associated with esophageal cancer present diagnostic and therapeutic issues. We investigated this synchronous association, and retrospectively determined the frequency of the gastric tumors and the clinical characteristics. METHODS: In a series of 208 patients with esophageal cancer, we investigated the synchronous gastric tumors, as well as the frequency of association, clinicopathological characteristics, diagnosis, treatment, and the clinical outcome after surgery. RESULTS: Twenty-eight gastric tumors were found in 24 patients. Adenocarcinoma was most frequent. Most of these tumors were located at the upper or middle third of the stomach. Eight gastric tumors in six patients could not be detected preoperatively. Six of these tumors including a gastric remnant cancer were detected in the resected stomach, and two leiomyomas were detected during the operation. In one patient in which an endoscope could not pass through the esophagus, a leiomyoma was detected in the resected stomach. For the gastric cancers, total gastrectomy or proximal gastrectomy with lymph node dissections was performed. For the benign tumors, partial resection of the stomach was performed, and endoscopic resection was performed preoperatively for an adenoma. In both the postoperative hospital mortality rate and the survival rate after surgery, there were no significant differences between the patients with and without gastric tumors. CONCLUSIONS: Synchronous gastric tumors associated with esophageal cancer are not rare. When an endoscope cannot pass through the esophagus before surgery, other techniques must be performed to explore the stomach. For these patients, surgical treatment should be adapted positively.

Aged↗
PubMed1998

Interaction of poliovirus with its purified receptor and conformational alteration in the virion.

Polypeptides of amino acids 1 to 241 (PVR241) and 1 to 330 (PVR330) of the human poliovirus receptor (hPVR) were produced in a baculovirus expression system. PVR241 contained extracellular domains 1 and 2 of hPVR, and PVR330 contained extracellular domains 1, 2, and 3. These peptides were purified by immunoaffinity column chromatography with an anti-hPVR monoclonal antibody (MAb). After the purification, PVR241 and PVR330 appeared to retain their native conformation as judged by reactivity with an anti-PVR MAb that recognized domain 1 of hPVR in a conformation-dependent manner. The virulent Mahoney strain of poliovirus type 1 was mixed with the purified PVRs in various concentrations. An average of at least 43 PVR330 molecules were able to bind to one virion particle under the conditions used. The equilibrium dissociation constant between the PVR330 molecule and the PVR binding site (canyon) on the virion was determined to be 4.50 +/- (0.86) x 10(-8) M at 4 degrees C. Higher rates of conformational change of the virus (160S) to 135S and 80S particles were observed as the concentration of PVR330 was increased. In this in vitro system, the ratio of the amount of the 135S particle to that of the 80S particle seemed to be always constant. After the disappearance of the 160S particle, the amount of the 80S particle was not increased by further incubation at 37 degrees C. These results suggested that the 80S particle was not derived from the 135S particle under the conditions used in this study.

Animals↗
PubMed1998

Calcitonin gene-related peptide-like immunoreactive motoneurons innervating the canine intrinsic laryngeal muscles.

The percentage of calcitonin gene-related peptide (CGRP)-immunoreactive motoneurons in the nucleus ambiguus innervating the intrinsic laryngeal muscles of colchicine-treated dogs was examined by using cholera toxin B subunit-gold (CTBG) as a retrograde tracer and by immunohistochemistry. Neurons that were labeled with CTBG from the cricothyroid muscle were located in the ventromedial division of the rostral part of the nucleus ambiguus, and the ratio of CGRP-positive neurons was 93.0%. Neurons labeled with CTBG from the thyroarytenoid muscle were located in the dorsal division of the medial part of the nucleus ambiguus, and the percentage of neurons with CGRP was 71.4%. Neurons labeled with CTBG from the posterior cricoarytenoid muscle were located in the ventral division of the medial part of the nucleus ambiguus, and the percentage of CGRP-positive neurons was 85.5%. These findings suggest that the innervation and/or the neurotrophic mechanism involving CGRP for each intrinsic laryngeal muscle is different.

Animals↗
PubMed1998

[Efficacy of multidirection MRCP].

Pancreatobiliary system has complex and thin structure except for gallbladder, thereby MRCP having lower spatial resolution gives sufficient information compared with the direct cholangiopancreatography. Multidirection MRCP using HASTE sequence obtains the data in plane to compensate the lower spatial resolution, thus high detectability of all over pancreatobiliary system is performed in a few minutes. This technique overcomes the demerits pointed by former investigators and gives sufficient information to diagnose the pancreatobiliary diseases.

Biliary Tract↗
PubMed1998

[Eighty cases of minimally invasive direct coronary artery bypass grafting].

Between March 1996 and November 1997, 80 patients with a mean age of 70 years (45-89) have undergone minimally invasive direct coronary artery bypass grafting via anterior minithoracotomy or subxiphoid incision with left internal thoracic artery and right epigastric artery using local coronary occlusion on a beating heart. Cardiac-related hospital mortality was 2.5% (2/80). Routine angiographic assessment of anastomotic patency showed an overall patency. rate of 94.6%, but demonstrated the severe stenosis at the anastomotic site in 8 patients. Further study is required to establish the efficacy of minimally invasive direct coronary artery bypass grafting and combination therapy with PTCA.

Aged↗
PubMed1998

[Continuous intraportal chemotherapy for prevention of metachronous hepatic metastasis in colorectal cancer].

Fifty-five colorectal cancer patients who had continuous intraportal chemotherapy between 1990 and 1993 (treated group) and 130 colorectal cancer patients who did not have portal chemotherapy between 1982 and 1993 (untreated group) were studied to clarify the effects of continuous intraportal chemotherapy on the prognosis. After a catheter was placed in the portal vein through the right gastroepiploic vein at the time of radical operation, 10 mg of MMC was continuously infused for 4 hours at operation and 500 mg/day of 5-FU was continuously infused for 7 days postoperatively. The toxicities of this therapy were not serious. The five-year survival rate was 65.3% in the treated group and 65.6% in the untreated group. The five-year disease-free survival rate was 69.8% in the treated group and 58.6% in the untreated group, with no significant difference. In stage II patients, however, the five-year disease-free survival rate in the treated group was slightly higher than in the untreated group (90.0% vs 70.3%, p = 0.073), and the rate of hepatic recurrence in the treated group was significantly lower than in the untreated group. These results suggest that continuous intraportal chemotherapy may prevent metachronous hepatic metastases in stage II colorectal cancer patients.

Aged↗
PubMed1998

[Sudden death during Holter electrocardiographic monitoring in a patient with hypertrophic cardiomyopathy].

A 56-year-old man visited a doctor because of arrhythmia and a diagnosis of hypertrophic cardiomyopathy was made in 1990. On January 9th, 1997, when aged 63 years old, he visited another doctor because of paroxysmal atrial fibrillation tachycardia. Since his clinical symptoms did not ameliorate, he visited our hospital on April 14th, and Holter electrocardiographic monitoring was started on April 16th. While walking on the street, his heart rate increased up to 107 beat/min when premature ventricular contraction with a long coupling interval of 400 msec occurred, followed by polymorphous ventricular tachycardia, ventricular fibrillation and death. He had no risk factors for sudden death such as early onset of symptoms, history of syncope, family history of sudden death, documented ventricular tachycardia, and congestive heart failure. Although many cases of hypertrophic cardiomyopathy end in sudden death, no electrocardiographic recordings at the time of sudden death have been available. This is the first case of electrocardiographic recording at the time of sudden death in a patient with hypertrophic cardiomyopathy.

Cardiomyopathy, Hypertrophic↗
PubMed1998

Nuclear matrix protein, tumor necrosis factor-alpha, and nitrite/nitrate levels in patients with multiple organ dysfunction syndrome.

Nuclear matrix protein (NMP), an indicator of apoptosis, was analyzed in patients with multiple organ dysfunction syndrome (MODS). Blood levels of tumor necrosis factor-alpha (TNF-alpha) and nitrite/nitrate (NOx) were also measured in these patients to determine the involvement of these factors in the production of NMP. Forty-six patients with MODS were studied, 21 (45.7%) of whom died. NMP and TNF-alpha were measured by enzyme-linked immunosorbent assay (ELISA). NOx was measured by the Griess's method. Marshall's multiple organ dysfunction score (MOD score) was used as an indicator of organ failure. The severity of organ failure was assessed by use of the acute physiology and chronic health evaluation II score (APACHE II score). The number of organs that failed was found to be significantly correlated with the NMP level. The NMP level was also correlated significantly with MOD score and APACHE II score, as well as with TNF-alpha and NOx levels. NMP and NOx levels in the group that died significantly exceeded those in the surviving group. Results suggest that apoptosis can occur in the presence of MODS, and that its extent increases as the number of failing organs increases. The results also suggest that TNF-alpha and NO are involved in the induction of apoptosis.

Adolescent↗
PubMed1998

[Comparative studies of breath-hold magnetic resonance cholangiopancreatography (MRCP) between different two sequences and between 1.0T and 1.5T units].

In this article, a comparative study in the diagnostic ability of a breath-hold MRCP between thin slice half-Fourier acquisition single-shot turbo spin-echo (HASTE) and thick slice rapid acquisition with relaxation enhancement (RARE), and between 1.5T and 1.0T units was made. Although thin slice HASTE sequence might be more excellent in the diagnostic ability than thick slice RARE, the ability of depiction of pancreaticobiliary system on MRCP was not statistically different between these two sequences and between 1.0T and 1.5T units. Thick slice RARE sequence was inferior to thin slice HASTE in the depiction of gallbladder stone. However, thick slice RARE sequence was useful for MRCP because a projection image of pancreaticobiliary system could be easily obtained without postprocessing and without misregistration. Thick slice RARE sequence should be used in combination with thin slice HASTE sequence for the diagnosis of pancreaticobiliary system.

Adult↗
PubMed1997

Mouse homolog of poliovirus receptor-related gene 2 product, mPRR2, mediates homophilic cell aggregation.

Poliovirus receptor (PVR) is a cell surface glycoprotein that belongs to the immunoglobulin superfamily. Although MPH was initially reported as the mouse homolog of human PVR, recent data strongly suggest that MPH is the mouse homolog of human PRR2, a PVR-related gene 2 product, and not that of human PVR. Thus MPH is renamed mPRR2 in this study. Physiological functions of the PVR-related gene products have not been elucidated, although PVR has been well characterized as the poliovirus receptor. In this study, a possible function of mPRR2 (MPH), which is not a functional receptor for poliovirus, was investigated. Mouse L cells expressing mPRR2 were prepared. Those mouse cells showed a higher activity of cell aggregation than the parental mouse L cells. Enhancement of cell aggregation was also observed for insect Sf9 cells infected with recombinant baculovirus carrying mPRR2 cDNA. On the other hand, L cells expressing human PVR or monkey PVR (AGM alpha1 or AGM alpha2) did not show increased cell aggregation. The cell aggregation activity of L cells expressing mPRR2 was inhibited by the addition of anti-mPRR2 monoclonal antibodies or a soluble mPRR2 molecule produced by the baculovirus expression system. An immunofluorescence study revealed that mPRR2 protein was localized to the cell-cell contact sites between cells expressing mPRR2. A similar localization of mPRR2 was observed for intrinsic mPRR2 molecules of the mouse neuroblastoma cell line NS20Y. The contact site-specific localization of mPRR2 was not observed on the border between mPRR2-expressing and nonexpressing HeLa cells. Furthermore, mPRR2 proteins directly bound to each other in vitro. mPRR2 was detected on various types of cultured cells of mouse origin and in various mouse tissues. These results suggest that mPRR2 is an intercellular adhesion molecule with a homophilic binding manner.

Animals↗
PubMed1997

Coexistence of calcitonin gene-related peptide and NADPH-diaphorase in the canine superior cervical ganglion.

By means of double staining technique of NADPH-diaphorase (NADPH-d) histochemistry and calcitonin gene-related peptide (CGRP) immunohistochemistry, we investigated the coexistence of NADPH-d reactivity and CGRP immunoreactivity in the canine superior cervical ganglion (SCG). Most of NADPH-d reactivity and CGRP immunoreactivity were coexisted in the principal postganglionic neurons. These neurons were distributed throughout the ganglion without specific localization. The present findings suggest the intimate role of CGRP and nitric oxide in postganglionic neurons of the canine SCG.

Animals↗
PubMed1997

Adverse effects of intraportal chemotherapy on natural killer cell activity in colorectal cancer patients.

BACKGROUND: Adjuvant intraportal chemotherapy has been used with a view to prevent the development of metachronous hepatic metastases following curative resection for colorectal cancer. To evaluate the effects of this therapy on systemic antitumor immunological activity, 35 colorectal cancer patients who underwent curative resection were investigated. METHOD: Among them. 19 had adjuvant intraportal chemotherapy with mitomycin C and 5-fluorouracil (treated group) and 16 had no chemotherapy (untreated group). Natural killer (NK) cell activity, lymphocyte subpopulations, and immunosuppressive acidic protein (IAP) in the peripheral blood were measured serially before and after operation, and the values were compared between the two groups. RESULTS: The NK cell activity and the percentages of CD16 positive and CD56 positive cells were markedly reduced in the treated group postoperatively. Significant difference was also observed between the two groups on the 4th postoperative day in regard to NK cell activity and CD56 positive cells. CONCLUSIONS: Intraportal chemotherapy in our study reduced the NK cell activity and its population in the peripheral blood.

Aged↗
PubMed1997

Immunohistochemical expression of bcl-2 protein in squamous cell carcinoma and basaloid carcinoma of the esophagus.

In the present study, the expression of bcl-2 protein in esophageal squamous cell carcinoma (SCC) and basaloid carcinoma (BC) was immunohistochemically examined, and its relation to tumor progression and postoperative survival was determined in SCC. A total of 42 SCC and 4 BC tumor samples were fixed with formalin, embedded in paraffin, and stained using monoclonal bcl-2 protein antibody, clone 124. Immunoreactivity was semiquantitatively scored, and the staining results were compared with the pathologic features and survival rates. The cytoplasm of basal cells from the normal esophageal epithelium was stained. In some well- and moderately differentiated SCCs, bcl-2 protein-positive reaction was observed in the peripheral part of the tumor cord, but in poorly differentiated SCC, the cells were weakly or hardly stained. However, in BC, the cells were strongly stained. The immunoreactivity was positive in 45.2% of the SCCs and all of the BCs. There were no significant differences in pathological features or patient survival between the bcl-2 protein-positive and protein-negative SCCs. In conclusion, the expression was not related to tumor progression and had no prognostic significance in SCC. Conversely, BC had strong immunohistochemical expression, probably associated with the differentiation of carcinoma cells simulating the basal cells of the esophagus.

Carcinoma, Squamous Cell↗
PubMed1997

Oesophageal cancer associated with other primary cancers: a study of 31 patients.

The aim of this study was to investigate the characteristics of oesophageal cancer associated with other primary cancers and the survival rate after surgery for the patients with these cancers. Of 202 patients with oesophageal cancer treated in the Second Department of Surgery, Shinshu University School of Medicine between 1981 and 1995, 31 patients (15.3%) had oesophageal cancer associated with other primary cancers. Twenty-one synchronous and 10 metachronous associated cancers were found and 25 of them were resected. Early-stage oesophageal cancer was much more frequent in the associated cases than in the non-associated cases. The stomach was the most frequently associated organ. The numbers of cases with triple and quadruple cancers were three and one, respectively. Three of these cases had intervals of over 6 years between tumours. Three cases with other primary cancers which had intervals of over 7 years after oesophagectomy were found, and two were carcinomas of the reconstructed gastric tube. In the outcome after surgery for oesophageal cancer, there was no difference between the associated and the non-associated cases, and also no difference between the synchronous and metachronous associated cases. Regarding the five-year and 10-year survival rates after surgery for the first cancers, the synchronous cases had a poorer outcome than did the metachronous cases. In conclusion, oesophageal cancer with other primary cancers is not always rare, and its outcome is not poor compared with that of the non-associated cases. These patients may achieve survival by early detection of both lesions and positive treatment. It is important to consider the risk of other primary cancers after oesophagectomy, and the success of the reconstructed gastric tube should be followed by endoscopy.

Aged↗
PubMed1997

Ventilation abnormalities in obstructive airways disorder: detection with pulmonary dynamic densitometry by means of spiral CT versus dynamic Xe-133 SPECT.

PURPOSE: To evaluate pulmonary dynamic densitometry (PDD) by means of spiral computed tomography (CT) for detection of ventilation abnormalities in obstructive airways disorders compared with dynamic xenon-133 single photon emission CT. MATERIALS AND METHODS: Eight-second spiral CT was performed during two to three respiratory cycles in six healthy volunteers, 19 patients with airways disorder, and six patients with restrictive lung disease. The data sets were reconstructed as 36 1-second temporally overlapping images at 0.2-second intervals, and regional PDD curves were displayed. Regional ventilation was assessed by means of Xe-133 clearance time. RESULTS: Normal lungs showed smooth, sinusoidal PDD curves with maximal amplitude in lung attenuation change (MALAC) of 54.9 HU +/- 24.5, whereas lungs with obstructive airways disorders with prolonged Xe-133 clearance showed significantly diminished MALAC (31.6 HU +/- 20.1, P < .0001), accompanied by irregularity, asynchronous phase, and deterioration of normal ventral-to-dorsal gradients in MALAC and lung attenuation. Lungs with restrictive diseases without prolonged Xe-133 clearance did not show statistically significant reduction in MALAC. In a total of 251 lung regions, regional MALAC correlated inversely with Xe-133 clearance time (r = -.842). CONCLUSION: PDD by means of spiral CT is acceptable for the detection of ventilation abnormalities in obstructive airways disorder.

Adult↗