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Biomedical subjects

Y Shoji

Publications and source records attributed to Y Shoji.

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

Role of nitric oxide and superoxide anion in elimination of low metastatic human colorectal carcinomas by unstimulated hepatic sinusoidal endothelial cells.

Human colorectal carcinoma (CRC) cell survival for the first 24 h after implantation in the hepatic sinusoid determines its potential to colonize the liver. Nearly 10-fold more highly metastatic CX-1 cells survive within the livers of nude mice 24 h after intrasplenic injection than weakly metastatic clone A cells. Because CRCs contact sinusoidal endothelial cells (SECs) during implantation, we sought to determine whether SECs were more toxic to clone A than to CX-1 cells. When 2 x 10(4) vital dye-labeled CRC cells were added to murine SEC monolayers, more than 30% of clone A cells lost calcein AM fluorescence compared to fewer than 5% of CX-1 cells after 24 h of coculture with SECs. Kupffer cells did not mediate this effect, because neither enriched Kupffer cells nor SECs treated with a Kupffer cell inhibitor altered the SEC-mediated toxic effect to clone A cells. Pretreatment with a nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine, superoxide dismutase, or dexamethasone, blocked SEC-mediated toxicity to clone A cells, whereas calcium chelation and catalase did not. In addition, clone A cells were more sensitive to a superoxide donor, 3-morpholinosydnonimine N-ethylcarbamide, than were CX-1 cells, and neither cell line was sensitive to sodium nitroprusside, a nitric oxide donor. Thus, unstimulated murine SECs produce reactive oxygen species that are selectively toxic to weakly metastatic clone A cells. This may be a mechanism by which host liver cells eliminate weakly metastatic neoplastic cells.

Animals↗
PubMed1998

Usefulness of bipolar scissors for total colectomy.

PURPOSE: Total colectomy is frequently used in colorectal surgery. We evaluated the usefulness of bipolar scissors in this operation. METHODS: Twenty patients with ulcerative colitis underwent total colectomy at Hyogo College Hospital. Bipolar scissors were used in ten randomly chosen colectomies. The resected major vessels of the colonic mesentery were stained by hematoxylin and eosin. The bursting pressure of the artery weld was measured with a water-filled, open-tip catheter. RESULTS: Both number of ligations and operating time were reduced by use of bipolar scissors. The cut edge of the major artery was occluded by the weld created, with a mean bursting pressure of 213 (range, 175-250) mmHg. CONCLUSION: Use of bipolar scissors was safe and had the advantage of shortening the operating time by decreasing the number of clamping and ligating procedures.

Adolescent↗
PubMed1998

Successful management of left main bronchial stenosis as a rare complication of pericardiectomy.

We present a rare complication of pericardiectomy and the effective management thereof. A 67-year-old female with dyspnea and upper abdominal pain was received at our department upon referral. Chest roentgenogram and cardiac catheterization preceded a diagnosis of constrictive pericarditis. Pericardiectomy was performed subordinate to median sternotomy and left anterolateral thoracotomy. Extubation was carried out on day 2 but reintubation was necessitated on the same day as a result of progressive dyspnea. Chest roentgenogram revealed an atelectasis of the left lung. Fiberoptic bronchoscopy showed left main bronchial stenosis resulting from a pulsating external structure. A postoperative computed tomogram substantiated the stenotic left main bronchus between the dilated left pulmonary artery and the thoracic descending aorta. An expandable metallic stent for the treatment of this complication was selected over other invasive procedures. Two years of follow-up reveal no complications. Accordingly, an expandable metallic stent has demonstrated its effectiveness not only on bronchial stenosis due to malignancy or tuberculosis but on benign cases such as this as well.

Aged↗
PubMed1998

[Open distal anastomosis or aortic balloon occlusion technique during complete aortic arch replacement].

The technique of open distal anastomosis or application of aortic balloon occlusion catheter designed to occlude the descending thoracic aorta have been used in 33 and 19 patients, respectively, to control bleeding during the procedure of distal anastomosis for complete aortic arch replacement with a prosthetic graft. These two techniques allowed us a simple approach to the lesion and the avoidance of clamp injury to the fragile aortic tissue. Open distal anastomosis was applied for 91% patients of operated aortic dissection and all emergent cases, it's duration ranged from 10 to 110 minutes with an average of 58 minutes under 18.2 degrees C of lowest esophageal temperature. On the other hand, aortic occlusion balloon was inserted for mainly true aortic aneurysm patients without an emergency, and helped to maintain the perfusion pressure on a lower part of body around 50 mmHg by the 1550 ml/min in an average of perfusion flow femoral artery under 21.2 degrees C of temperature. The difference of postoperative renal and liver function evaluated by serum enzyme levels of total bilirubin, GOT, GPT, LDH, creatinine and BUN did not reach to statistical significance between the patients using open distal anastomosis and balloon occlusion, however, the incidence of postoperative complication including either renal, liver dysfunction, abdominal problem or paraplegia was significantly higher in the patient group with open distal technique. Either open distal anastomosis or aortic balloon occlusion technique would be appropriately selected according to the patient's characteristics or the condition of aortic disease to be operated.

Aged↗
PubMed1998

Evidence of an increased risk of hearing loss in heterozygous carriers in a Wolfram syndrome family.

Wolfram syndrome (MIM 222300) is characterized by juvenile-onset diabetes mellitus and optic atrophy. Previous linkage analyses in the United States and UK families have indicated that the gene for Wolfram syndrome (WFS) is localized on the short arm of chromosome 4. We herein confirm the linkage of the WFS locus to D4S3023 on 4p with a two-point LOD score of 3.42 in a large Japanese family with Wolfram syndrome. Multipoint linkage analysis revealed the maximum LOD score of 4.82 between D4S3023 and D4S394. We also evaluated putative health risks in carriers by multiple logistic analysis with independent variables, age, gender, and numbers of affected haplotypes and with dependent variables, such as hearing loss, diabetes mellitus, polyuria, incontinence, psychological illness, and visual acuity. The results showed that the putative disease haplotype increased a risk of hearing loss (odds ratio =35.68, 95% confidence interval =4.12-308.95) and diabetes mellitus (odds ratio =7.57, 95% confidence interval =2.03-28.23) independently. This is the first report of an increased health risk of illness in carriers, other than for psychiatric disease.

Adolescent↗
PubMed1998

Hyperammonemia reduces water immersion--restraint stress gastric ulcers in rats.

1. The influence of hyperammonemia (produced by the continuous intraperitoneal infusion of ammonium acetate for 6 days) on stress-induced gastric ulcer formation was investigated in conscious rats. 2. Continuous ammonium acetate infusion significantly reduced stress-induced gastric ulceration concomitant with an increase in gastric blood flow, as determined using radioactive microspheres. The serum levels of L-arginine as well as nitrite and nitrate (oxidative byproducts of nitric oxide) were increased by ammonium acetate infusion. 3. Prior administration of N omega-nitro-L-arginine methyl ester, a competitive nitric oxide synthase inhibitor, substantially attenuated the increase in gastric blood flow caused by ammonium acetate infusion and diminished the protective effect on gastric ulceration. 4. These findings suggest that the synthesis of endogenous nitric oxide from L-arginine is accelerated by continuous ammonium acetate infusion when the urea cycle remains intact and has a substantial cytoprotective effect on the stomach, probably through maintaining the gastric mucosal microcirculation.

Acetates↗
PubMed1998

Mutational analyses in four Japanese families with X-linked liver phosphorylase kinase deficiency type 1.

We analysed the gene of the human alpha-subunit of liver phosphorylase kinase (PHKA2) in four Japanese families with X-linked liver phosphorylase kinase deficiency type 1 by RT-PCR followed by PCR-single-strand conformation polymorphism and direct DNA sequencing. In this study, two novel mutations (Y116D and 2675A-->G) and one mutation previously reported (P1205L) were identified, revealing molecular heterogeneity in Japanese patients. Considering the dissimilarity in phenotype among our patients even with an identical mutation in the PHKA2 gene, it seems that each genetic deficiency in this gene may not be the only factor to determine the clinical heterogeneity in this disease.

Base Sequence↗
PubMed1998

Evidence for linkage of human primary systemic carnitine deficiency with D5S436: a novel gene locus on chromosome 5q.

Primary systemic carnitine deficiency (SCD) is a rare hereditary disorder transmitted by an autosomal recessive mode of inheritance. The disorder includes cardiomyopathy, muscle weakness, hypoketotic coma with hypoglycemia, and hyperammonemia. In this study, we conducted a linkage analysis of a Japanese SCD family with a proband-a 9-year-old girl-and 26 members. The serum and urinary carnitine levels were determined for all members. The entire genome was searched for linkage to the gene locus for SCD, by use of a total of approximately 300 polymorphic markers located approximately 15-20 cM apart. In the family, there were two significantly different phenotypes, in terms of serum free-carnitine levels: low serum free-carnitine level (29.5+/-5.0 microM; n=14) and normal serum free-carnitine level (46.8+/-6.2 microM; n=12). There was no correlation of urinary free-carnitine levels with the low serum-level phenotype (putative heterozygote), but in normal phenotypes (wild type) urinary levels decreased as the serum levels decreased; renal resorption of free carnitine appeared to be complete in wild-type individuals, when the serum free-carnitine level was <36 microM. Linkage analysis using an autosomal dominant mode of inheritance of heterozygosity revealed a tight linkage between the disease allele and D5S436 on chromosome 5q, with a two-point LOD score of 4.98 and a multipoint LOD score of 5.52. The haplotype analysis revealed that the responsible genetic locus lies between D5S658 and D5S434, which we named the "SCD" locus. This region was syntenic with the jvs locus, which is responsible for murine SCD. Phylogenic conversion of the SCD locus strongly suggests involvement of a single gene, in human SCD.

Carnitine↗
PubMed1998

Limited use of cationic liposomes as tools to enhance the antiherpetic activities of oligonucleotides in vero cells infected with herpes simplex virus type 1.

We used commercially available cationic liposomes, lipofectin, DOTAP, and transfectam, to enhance the antiherpetic activities of phosphodiester oligonucleotides (D-oligos) or phosphorothioate oligonucleotides (S-oligos) targeted against immediate-early pre-mRNA4/5 of herpes simplex virus type 1 (HSV-1). With a 5-fold excess of S-oligos/D-oligos, formation of complexes with some of the S-oligos/D-oligos and the cationic liposomes could be visualized on agarose gel. A >5-fold excess of cationic liposomes enhanced the antiherpetic activities of Doligos, whereas there was not enhancement of the antiherpetic activities of S-oligos. As nuclear localization of D-oligos in the presence of cationic liposomes was not clear, we could not clarify the relation between antiherpetic activities of D-oligos and nuclear distribution of oligos. Subcellular distribution of S-oligos in the presence of lipofectin or DOTAP showed nuclear localization by confocal laser scanning microscopy. Transfectam had no effect on the nuclear distribution of S-oligos. These data showed that cationic liposomes would not be appropriate carriers to enhance the antiherpetic activities of S-oligos. Also, distribution of S-oligos into the nucleus does not necessarily enhance their biologic activity. Questions remain about the effectiveness of cationic liposomes in the enhancement of the antivirus activity of S-oligos.

Animals↗
PubMed1998

Mechanisms underlying the enhancement of excitatory synaptic transmission in basolateral amygdala neurons of the kindling rat.

To elucidate the mechanism underlying epileptiform discharges in kindled rats, synaptic responses in kindled basolateral amygdala neurons in vitro were compared with those from control rats by using intracellular and whole cell patch-clamp recordings. In kindled neurons, electrical stimulation of the stria terminalis induced epileptiform discharges. The resting potential, apparent input resistance, current-voltage relationship of the membrane, and the threshold, amplitude, and duration of action potentials in kindled neurons were not different from those in control neurons. The electrical stimulation of stria terminalis elicited excitatory postsynaptic potentials (EPSPs) and DL-2-amino-5-phosphonopentanoic acid (AP5)-sensitive and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX)-sensitive excitatory postsynaptic currents (EPSCs). The amplitude of evoked EPSPs and of evoked AP5-sensitive and CNQX-sensitive EPSCs were enhanced markedly, whereas fast and slow inhibitory postsynaptic potentials (IPSPs) induced by electrical stimulation of lateral amygdaloid nucleus were not significantly different. The rise time and the decay time constant of the evoked CNQX-sensitive EPSCs were shortened, whereas the rise time of the evoked AP5-sensitive EPSCs was shortened, but the decay time constants were not significantly different. In both tetrodotoxin (TTX)-containing medium and low Ca2+ and TTX-containing medium, the frequency and amplitude of spontaneous EPSCs were increased in kindled neurons. These increases are presumably due to nearly synchronous multiquantal events resulted from the increased probability of Glu release at the nerve terminals. The rise time of evoked CNQX- and AP5-sensitive EPSCs and the decay time constant of evoked CNQX-sensitive EPSCs were shortened, suggesting that excitatory synapses at the proximal dendrite and/or the soma in kindled neurons may contribute more effectively to generate evoked EPSCs than those at distal dendrites. In conclusion, the increases in the amplitudes of spontaneous and evoked EPSCs and in the frequency of spontaneous EPSCs may contribute to the epileptiform discharges in kindled neurons.

2-Amino-5-phosphonovalerate↗
PubMed1998

A comparison of stapled and hand-sewn anastomoses in Crohn's disease.

Sixty-eight patients with Crohn's disease who underwent intestinal resection were randomly divided into 2 groups: the stapled group (32 patients, 40 anastomoses) with functional end-to-end anastomoses made with linear staplers and with circular stapling anastomoses, and the hand-sewn group (36 patients, 48 anastomoses), with anastomoses achieved by layer-to-layer suturing. There were no significant differences in operative indications, age, sex, blood loss, or length of hospital stay between the groups. The operation times for right hemicolectomy and total colectomy in the stapled group were significantly shorter than those in the hand-sewn group. There were no significant differences in anastomotic dehiscence or recurrence between the stapling and hand-sewn procedures. These results indicate that these stapling techniques, even though producing an everted anastomosis, are not an adverse procedure for Crohn's disease.

Adolescent↗
PubMed1998

Enzyme therapy in Gaucher disease type 2: an autopsy case.

A Japanese patient with Gaucher disease type 2 was treated with enzyme therapy, alglucerase, from 7 to 22 months of age. Whereas hematologic parameters were normalized and hepatosplenomegaly was alleviated, no improvement in neurologic symptoms occurred, and the patient died of respiratory failure at age 22 months. Postmortem examination revealed massive intra-alveolar infiltration of Gaucher cells in lungs and in the central nervous system, i.e., the presence of Gaucher cells in the perivascular Virchow-Robins spaces in the cortex and deep white matter and extensive lamilar necrosis with reactive proliferation of blood vessels and macrophage infiltration of the cerebral cortex. It is suggested that enzyme therapy, with thus far recommended dose, does not prevent long-term respiratory and central nervous system involvement in severe varients of Gaucher disease.

Brain↗
PubMed1998

Enhancement of anti-herpetic activity of antisense phosphorothioate oligonucleotides 5' end modified with geraniol.

We have previously shown that antisense phosphorothioate oligonucleotide (SON) targeted against immediate early (IE) pre-mRNA5 of the herpes simplex virus type I (HSV-I) possessed potent anti-herpetic activities in vitro system. However, anti-herpetic activities of SON were not still efficient enough. Lipophilic compounds have been often conjugated with antisense oligonucleotide to enhance the biological activity. In this study, we selected geraniol as a lipophilic compound and newly synthesized SON bearing 5' terminal geraniol (geranyl-SON) toward IE pre-mRNA 5 of the HSV-1 to enhance the anti-herpetic activity. Geraniol is a olefinic terpene alcohol which is found in many essential oils. It possesses lipophilic characteristic. It is thought to be absorbed in tissue. Geraniol enhanced the anti-herpetic activity of SON with less cytotoxicity in a sequence specific manner. Terminal modification with geraniol did not affect binding affinity with complimentary DNA. Cytoplasm distribution of geranyl-SON was confirmed by confocal microscope. While some of the geranyl-SON was seen in the nucleus, unmodified SON had a punctate distribution in the cytoplasm with little in the nucleus. These results suggested that geranyl modification enhances anti-herpetic activity by changing the subcellular distribution of the oligonucleotides. Consequently geraniol-modifica-tion could provide new means for the efficient delivery of oligo-nucleotides.

Acyclic Monoterpenes↗
PubMed1998

Effects of scatter and attenuation correction on quantitative assessment of regional cerebral blood flow with SPECT.

UNLABELLED: Appropriate corrections for scatter and attenuation correction are prerequisites for quantitative SPECT studies. However, in most cerebral SPECT studies, uniform attenuation in the head is assumed, and scatter is usually neglected. This study evaluated the effect of attenuation correction and scatter correction on quantitative values and image contrast. METHODS: Studies were performed in six normal volunteers (ages 22-26 yr) following intravenous 123I-IMP administration using a rotating, dual-head gamma camera. A transmission scan was acquired with a 99mTc rod source (74 MBq) placed at the focus of a symmetrical fanbeam collimator. Data were reconstructed using two attenuation coefficient (mu) maps: quantitative mu map from the transmission scan and a uniform mu map generated by edge detection of the reconstructed images. Narrow and broad beam mu values were used with and without scatter correction, respectively. Scatter was corrected with transmission-dependent convolution subtraction and triple-energy window techniques. Quantitative rCBF images were calculated by the previously validated IMP-autoradiographic technique, and they were compared with those obtained by (15)O-water and PET. SPECT and PET images were registered to MRI studies, and rCBF values were compared in 39 ROIs selected on MRI. RESULTS: Clear differences were observed in rCBF images between the measured and constant mu maps in the lower slices due to the airways and in the higher slices due to increased skull attenuation. However, differences were < 5% in all cerebral tissue regions, thus assumption of uniform mu introduces little bias. The scatter correction was found to increase the image contrast significantly, i.e., rCBF increased by 20%-30% in gray matter and decreased in white matter regions by 10%-20% after scatter correction, increasing gray-to-white ratio to be close to that of PET measurement. The rCBF values from the two scatter correction were not significantly different, but the triple-energy window technique suffered from increased noise. After scatter correction, rCBF values were in good agreement with those measured by PET. CONCLUSION: This study shows little loss in accuracy results from assuming uniform mu map. However, scatter correction is required for the quantitative rCBF values and gray-to-white ratios to approach those of PET.

Adult↗
PubMed1998

[Brain damage following aortic arch repair with regard to techniques of selective cerebral perfusion and preoperative cerebral lesions].

One hundred and twenty-nine aortic aneurysm patients (true 68 and dissection 61) underwent aortic arch repair from January 1987 to December 1995. Postoperative brain damage was evaluated regarding both preoperative brain lesions and techniques of selective cerebral perfusion (SCP) in that one pump for SCP until April 1992, then two pumps were employed, one for right and the other for left hemisphere of the brain. Overall hospital mortalities were 21% in true and 13% in dissecting aneurysms. Ten patients were complicated with postoperative brain damages (coma 8 and hemiplegia 2), registering 7.8% of total patients. Both history of stroke and silent cerebral infarction (SCI) detected by CT and/or MRI were considered to be positive in the mean of having preoperative brain lesions. Although there was no significant difference between incidences of postoperative brain damage in true and dissecting aneurysms, registering 11% and 4% respectively, preoperative brain lesions in true aneurysm (68%) was significantly greater than dissecting aneurysm (32%). Furthermore, the incidence of postoperative brain damage was 22% in one-pump SCP which was significantly greater than 3% in two-pumps SCP in the patients with a true aneurysm. But there was no postoperative brain complication in patients with SCI even using either one two pumps for SCP. The present data suggest two-pumps SCP is better technique for cerebral protection compared to one-pump SCP for aortic arch repair.

Adult↗