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S Funahashi

Publications and source records attributed to S Funahashi.

At least 37 records · Page 2Linked to original sources
PubMed1996

Expression of c-fos gene inhibits proteoglycan synthesis in transfected chondrocyte.

The effect of expression of c-fos gene on proteoglycan synthesis, one of the important markers of cartilage metabolism, was examined by introducing the c-fos DNA into HCS 2/8 chondrocytes. The [35S]sulfate incorporation into proteoglycan was decreased in the c-fos transfectants expressing exogenous c-fos mRNA, when compared to a control transfectant. A significant increase in transcription of MMP-3 with the suppressed transcription of aggrecan and TIMP-1 were also observed in the c-fos transfectants. Moreover, analysis of the effect of AP-1 proteins on the collagenase and TIMP-1 promoters in gastric carcinoma KKLS cells revealed that c-Fos combined with any of the Jun-related proteins failed to stimulate the TIMP-1 promoter, though collagenase promoter was effectively activated by any Fos/Jun-related protein heterocomplex. These findings indicate that the c-fos expression may govern the cartilage metabolism and hence may play an important role in the pathogenesis of joint destruction in arthritis.

Base Sequence↗
PubMed1996

Effects of lumbar sympathectomy on the properties of both endothelium and smooth muscle cells of the canine femoral artery and autogenous vein grafts under poor runoff conditions.

The purpose of this study was to determine whether or not a lumbar sympathectomy would modulate the functions of the endothelium, in terms of endothelium-derived relaxing factor (EDRF), under poor distal runoff conditions. First, a poor distal runoff model was developed in the canine right and left femoral arteries. After 5 weeks, a unilateral left sympathectomy was performed from L-3 to L-6. In experiment I, changes in blood flow and endothelium-dependent responses were examined in the canine femoral artery 5 weeks after the lumbar sympathectomy. In experiment II, 5 weeks after the development of a poor runoff model, a unilateral left sympathectomy was performed and both femoral veins were also grafted to the femoral arteries on both sides. Then after 4 weeks, endothelium-dependent responses and intimal thickening of both autogenous vein grafts were examined. The endothelium-dependent responses were examined by mechanical tension recording. In both experiments, the mean blood flow of the left femoral arteries (denervated, 92.2 +/- 47.1 ml/min) and vein grafts (denervated, 100.0 +/- 35.4 ml/min) was significantly higher than that of the right femoral arteries (innervated, 46.9 +/-25.7 ml/min) and vein grafts (innervated, 50.0 +/- 20.1 ml/min) (P < 0.01). In experiment I, the endothelium-dependent relaxations to acetylcholine, ADP, and A23187 were comparable between the right and left femoral arteries. In experiment II, the endothelium-independent contractions to acetylcholine and endothelium-dependent relaxations to ADP and A23187 were all comparable between the right and left vein grafts. In addition, the intimal thickening of the vein graft was comparable between the two groups (denervated, 95.6 +/- 10.8 microm; innervated, 105.0 +/- 15.0 microm). In both experiments, the NE-induced contractions and SNP-induced relaxations were closely similar between the two groups, irrespective of the flow change. These results suggest that lumbar sympathectomy does not alter endothelial function in terms of EDRF, although mean blood flow of the denervated femoral arteries and vein grafts was significantly higher than that of the innervated femoral arteries and vein grafts. These results suggest that continuous vasodilation following sympathectomy may be a more potent factor with respect to regulation of vascular tonus than physiologic regulation of EDRF.

Acetylcholine↗
PubMed1996

Postoperative bile peritonitis caused by division of an aberrant bile duct in the left triangular ligament of the liver.

A 61-yr-old man underwent Billroth I gastrectomy for an advanced cancer in the corpus of the stomach. On the first postoperative day, fresh bile discharged from the penrose drains, which had been placed in Winslow's foramen, and the volume of bile discharge subsequently increased. Leakage from the gastroduodenal anastomosis was excluded by gastroduodenography. Exploratory relaparotomy showed bile peritonitis with much more bile retention in the left subphrenic space. The origin of bile leakage could not be traced despite close examination of all the extrahepatic biliary tract and the liver surface. Intraoperative cholangiography through the cystic duct after cholecystectomy revealed that the bile leakage originated from an aberrant bile duct present in the free edge of the left triangular ligament (appendix fibrosa hepatis), which had been unintentionally cut at the primary operation. Knowledge of this anatomical structure is important and proper ligation is recommended when dissecting the appendix fibrosa hepatis to avoid postoperative bile peritonitis and the need for a relaparotomy.

Bile↗
PubMed1995

Relationship between peritoneal collagen type IV concentrations and the presence of disseminated metastases in gastric cancer.

OBJECTIVE: To predict disseminated microscopic foci or occult micrometastases in the peritoneal cavity in patients with gastric cancer. DESIGN: Randomly selected patients with gastric cancer had peritoneal washings performed at the beginning of laparotomy. PATIENTS: Thirty-nine patients with gastric carcinoma and 10 patients with other benign disease as a control group. SETTING: Inpatients in a surgical department. INTERVENTIONS: The concentration of collagen type IV in the irrigated peritoneal fluid was measured radioimmunologically. Intraoperative peritoneal cytologic examination and measurements of carcinoembryonic antigen (CEA) levels were also performed. MAIN OUTCOME MEASUREMENTS: Results of the quantitative analyses of the collagen type IV concentrations as related to the clinicopathological characteristics and comparison of these results with regard to those of the peritoneal cytologic examination and CEA and collagen type IV levels. RESULTS: There were eight patients with elevated collagen type IV concentrations. They had carcinomas with serosal invasion (pT3 and pT4) and metastatic spread (pN2, M1). Patients with clinically evident peritoneal disseminated metastases had significantly higher collagen type IV concentrations compared with those without metastases. The collagen type IV levels were more sensitive than peritoneal cytologic examination or CEA values in detecting disseminated metastases. There was an early peritoneal recurrence in the form of ovarian metastases in one patient with negative cytologic results and an elevated collagen type IV level. Linear regression analysis showed a statistically significant correlation between the collagen type IV and CEA levels. CONCLUSION: Quantitative detection of abnormal collagen type IV levels may be useful for predicting the presence of disseminated metastases in patients with gastric cancer.

Adult↗
PubMed1995

Late graft failure of autologous vein grafts for arterial occlusive disease: clinical and experimental studies.

Late graft failure following arterial reconstructive surgery, especially after infrainguinal reconstruction, remains a major concern for vascular surgeons. To more effectively predict the outcome of reconstructed arteries, we herein propose an intraoperative flow waveform analysis which correlates well with the long-term patency rate of grafts. According to this flow waveform analysis, late graft failure was occasionally seen in grafts with type II waveforms when poor distal runoff vessels had been shown by the preoperative arteriogram. Next, to investigate which events occurring in autologous vein grafts under abnormal hemodynamics may contribute to late graft failure, a distal poor-runoff model was made in the canine femoral artery. In this review, we present the results of our investigation on autologous vein grafts using this poor-runoff model. We also relate our recent findings on the function of regenerated endothelium in autologous vein grafts.

Animals↗
PubMed1995

[Advanced gastric carcinoma with extensive lymph node metastases successfully treated by sequential methotrexate/5-fluorouracil therapy].

A 62-year-old man having advanced gastric carcinoma with extended lymph node metastases was successfully treated by a palliative gastrectomy and 6 courses of sequential methotrexate/5-fluorouracil therapy. No side effects were observed, and all enlarged abdominal lymph nodes disappeared. The complete response has continued for 11 months after the initial treatment.

Adenocarcinoma↗
PubMed1994

Phylogenetic subtypes of human T-lymphotropic virus type I and their relations to the anthropological background.

Isolates of human T-lymphotropic virus type I (HTLV-I) were phylogenetically analyzed from native inhabitants in India and South America (Colombia and Chile) and from Ainu (regarded as pure Japanese descendants from the preagricultural "Jomon" period). Their genomes were partially sequenced together with isolates from Gabon in central Africa and from Ghana in West Africa. The phylogenetic tree was constructed from the sequence data obtained and those of previously reported HTLV-I isolates and simian T-lymphotropic virus type I (STLV-I) isolates. The heterogeneity of HTLV-I was recently recognized, and one major type, generally called the "cosmopolitan" type, contained Japanese, Caribbean, and West African isolates. The phylogenetic tree constructed in the present study has shown that this cosmopolitan type can be further grouped into three lineages (subtypes A, B, and C). Subtype A consists of some Caribbean, two South American, and some Japanese isolates, including that from the Ainu, in addition to an Indian isolate, and subtype B consists of other Japanese isolates in addition to another Indian isolate, suggesting that there might be at least two ancestral lineages of the Japanese HTLV-I. Subtype A implies a close connection of the Caribbean and South American natives with the Japanese and thereby a possible migration of the lineage to the American continent via Beringia in the Paleolithic era. Subtype C consists of the West African and other Caribbean isolates, indicating that not all but part of the Caribbean strains directly originated from West Africa probably during the period of slave trade. The tree also has shown that the HTLV-I isolate from Gabon in central Africa forms a cluster with STLV-I from a chimpanzee, suggesting a possible interspecies transmission between man and the chimpanzee in the past. No specific clustering was observed in the tree in relation to manifestations of the disease such as adult T-cell leukemia and HTLV-I-related neurological disorders. Thus, the topology of the phylogenetic tree reflects the movement of people carrying the virus in the past.

Adult↗
PubMed1994

Constructions of vaccinia virus A-type inclusion body protein, tandemly repeated mutant 7.5 kDa protein, and hemagglutinin gene promoters support high levels of expression.

We devised vaccinia virus (VV)-based vector systems that support higher levels of expression of cloned genes in the early and late phases of the infection cycle than reported previously. Enhanced expression can be obtained by combining the promoter of the A-type inclusion body protein gene, the mutated early region of the 7.5-kDa gene promoter (7.5-kDa promoter), and the promoter of the hemagglutinin (HA) gene. One construct produced 60 micrograms/10(6) cells of chloramphenicol acetyltransferase (CAT), equivalent to 10-18% of total cell protein. Another construct produced about seven times more CAT during the early phase than the amount synthesized under the control of the 7.5-kDa promoter alone. The envelope proteins of human immunodeficiency virus type I synthesized during the early phase of infection were more active as immunogens than these proteins synthesized during the late phase, regardless of the amounts produced.

Animals↗
PubMed1994

Intimal hyperplasia of experimental autologous vein graft in hyperlipidemic rabbits with poor distal runoff.

Poor distal runoff and hyperlipidemia are factors affecting the fate of an implanted graft. In the present study, combined effects of poor distal runoff and hyperlipidemia on intimal hyperplasia (IH) of the vein graft were examined in a newly developed poor distal runoff model in rabbits. A poor distal runoff model was prepared in the right hindlimb of 30 rabbits. These animals were divided into two groups, depending on the diet provided; normolipidemic diet group (Group NL, n = 14) and hyperlipidemic 1% cholesterol diet group (Group HL, n = 16). Four weeks after preparing the poor runoff model, the femoral vein was implanted into the ipsilateral femoral artery. At 2, 4 and 6 weeks, the grafts were harvested. IH of the graft was measured and macrophages in the IH were examined immunohistochemically. Intimal cell proliferation was also determined by bromodeoxyuridine (BrdU) incorporation. IH of the vein graft was significantly accelerated in cases of poor distal runoff and hyperlipidemia. There were no macrophages in the IH in the NL group. In the HL group, macrophages infiltrated the outer layer of IH, sometimes just above the internal elastic lamina, and increased with time. In the poor distal runoff limbs at 6 weeks, macrophages also appeared in the subendothelial layer but were absent in that layer in the controls. Intimal cell proliferation expressed as the BrdU labeling index (LI) was maximum at 2 weeks. In the HL group, BrdU LI of IH in the poor distal runoff limb was higher than in the control at 2 and 4 weeks. Throughout the experiments, BrdU LIs in the HL group were significantly higher than in the NL. Hyperlipidemia accelerates intimal cell proliferation to a greater extent, then does IH. In cases of a poor distal runoff, the enhancement of cell proliferation by hyperlipidemia is augmented. These responses, in the presence of a hyperlipidemia, may be closely related to the migration of macrophages.

Animals↗
PubMed1994

Working memory and prefrontal cortex.

Several different types of memory have recently been proposed, some of which are believed to operate within specific areas in the brain. In this article, we will discuss the relationship between the prefrontal cortex and working memory, which is a recently proposed type of short-term memory. The tight relationship between the prefrontal cortex and working memory has been supported by recent human and animal studies. This relationship provides good evidence that a particular type of memory is related to a particular brain structure, and can be used as an important model for understanding the neuronal mechanisms of memory. In this article, we will present a modular model based on recent neurophysiological results and discuss for spatial working memory processes in the prefrontal cortex.

Animals↗
PubMed1994

Surgical strategy of concomitant abdominal aortic aneurysm and gastric cancer.

PURPOSE: Selecting the most appropriate surgical approach for patients with abdominal aortic aneurysm (AAA) and concurrent gastric cancer remains controversial. In an attempt to develop guidelines for the management of two concurrent lesions, a retrospective review of patients with concomitant AAA and gastric cancer was undertaken. METHODS: During the period from January 1985 to December 1992, a total of 222 patients with AAA were admitted to our hospital. Among these, seven patients (3.2%) had gastric cancer and concurrent AAA. Six of the seven patients were treated surgically for both lesions with either a one- or two-stage operation. One patient underwent only an exploratory laparotomy because of the peritoneal dissemination of the gastric cancer. Four of the six patients underwent a two-stage operation. In three cases, the resection of the malignancy was performed first because the gastric cancer was diagnosed as advanced before operation. In one case, the aneurysmectomy was performed first because the aneurysm was more than 6 cm in diameter and the gastric cancer was in an early stage of development. Two of the six patients underwent a one-stage operation and a simultaneous resection was carried out by way of segregated approaches, such as the retroperitoneal approach for AAA and the transperitoneal approach for the malignant lesion. RESULTS: Five of the seven patients (71.4%) are still alive. The length of follow-up for these patients ranged from 4 months to 4 years. CONCLUSIONS: The principles of our surgical approaches for concomitant AAA and gastric cancer are as follows. (1) The lesion that absolutely indicates urgent operation should be operated on first. (2) If the malignant lesion is advanced, it is resected first. (3) If the malignancy is not advanced, the AAA should be resected first by the retroperitoneal approach. (4) Simultaneous resection by way of segregated approaches is useful in some patients with early gastric cancer. (5) Both lesions must be resected eventually for improvement of the long-term survival chances.

Aged↗
PubMed1994

Do patients with intermittent claudication need surgical treatment?

To determine whether surgical intervention is of therapeutic significance for patients with intermittent claudication (IC), 315 patients with IC followed in our outpatient clinics for the past 8 years 3 months (mean of 3 years 10 months), including 142 non-operated and 173 operated patients, were investigated as to changes in symptoms and the prognosis. Changes in symptoms in both groups were analyzed according to the variable distances of claudication and location of the diseased artery. To examine the degree of association between surgery and improvement of symptoms, Goodman and Kruskal's gamma was used. For all subgroups with a variable claudication distance (group A; distance < 100 m, B: 100-500 m, C: > 500 m), surgery inversely correlated with improvement in symptoms (group A; gamma = -0.378, group B; gamma = -0.651, group C; gamma = -0.828). According to location of the diseased artery, surgery correlated with improvement in symptoms in aorto-iliac (gamma = -0.811), aorto-ilio-superficial femoral (gamma = -0.641), and superficial femoral-distal (gamma = -0.533) groups but not in superficial femoral (gamma = -0.427) or infrapopliteal (gamma = -0.194) alone groups. Concerning the prognosis, no significant difference was noted between operated and non-operated groups (p = 0.35). These computed data show that surgical intervention has therapeutic significance for patients with IC, except for cases of claudication with segmental occlusion of the superficial femoral or infrapopliteal artery alone.

Aged↗
PubMed1994

Persistent sciatic artery: two case reports and a review of the literature.

Persistent sciatic artery (PSA) sometimes shows variant vascular symptoms such as chronic or acute limb ischaemia and a pulsatile mass in the buttocks caused by aneurysmal dilatation. This report presents two cases of surgically treated PSA that caused lower-limb ischaemia. The first patient, a 58-year-old man, showed acute limb ischaemia in the chronic clinical course, and thrombectomy and patch angioplasty were performed. The second patient, a 70-year-old woman, had an incomplete type of PSA without development of the femoral artery while complaining of a 10-year history of coldness and numbness in the left lower limb. A left common iliac to profunda femoris arterial bypass was performed. This is the second case of symptomatic incomplete PSA reported in the literature. This report also reviews 45 cases of PSA published since 1977. The diagnosis of PSA requires arteriography that includes the bilateral iliac systems. Femoropopliteal bypass and, in the case of sciatic artery aneurysm, a ligature of the sciatic artery are recommended for the surgical treatment of PSA.

Aged↗
PubMed1993

Prefrontal neuronal activity in rhesus monkeys performing a delayed anti-saccade task.

Patients with damage to the dorsolateral prefrontal cortex are impaired on cognitive tasks such as the Wisconsin Card Sort Test, the Stroop Test and an anti-saccade paradigm, in which sensory-guided habitual responses must be suppressed in favour of conceptually or memory-guided responses. We report here recordings from prefrontal neurons in rhesus monkeys trained to perform a delayed anti-saccade task based on tests that have been used with humans. Activity in the same prefrontal neurons was recorded across conditions when saccades were made toward a remembered target, and also when this prepotent response was suppressed and a saccade in the opposite direction required. Our findings show that most prefrontal neurons code the location of the visual stimulus in working memory, and that this memory can be engaged to suppress as well as prescribe a response. These results establish, in a subset of prefrontal neurons, the iconic nature of the memory code, and suggest a role for visual memory in response suppression.

Animals↗
PubMed1993

Operative transluminal laser angioplasty as the sole treatment for late stenoses of femorodistal artery bypass graft: experimental and clinical studies.

To determine the role of Nd:YAG laser thermal angioplasty as the sole treatment for late stenoses of femorodistal artery bypass graft, the lasing effect of a larger size of hot-tip probe (3, 4, and 5 mm) was experimentally studied in vitro. For an adequate lasing effect, 30 watts of laser power output for 3 seconds was needed for the 3 mm probe, 40 watts for the 4 mm probe, and 50 watts for the 5 mm probe, respectively. Based on these results, we used Nd:YAG laser thermal angioplasty alone for 25 grafts, including 16 polytetrafluoroethylene (PTFE) grafts, eight saphenous vein grafts, and one externally supported (EXS) Dacron graft in which the stenotic lesions were detected by deterioration of the Doppler flow waveform pattern or a significant fall in the ankle/brachial pressure index (ABPI). Follow-up was from 3 to 24 months (average of 9 months) for PTFE grafts, from 5 to 21 months (average of 11 months) for saphenous vein grafts, and 13 months for the EXS Dacron graft following femorodistal artery reconstructions. Stenotic lesions were most common in the distal anastomotic sites: 11 PTFE grafts, three saphenous vein grafts, and one EXS Dacron graft. Among these, 13 grafts showed a type II flow waveform pattern at the time of surgery. Clinical success was achieved in 12 of the PTFE grafts (75%), in five of the vein grafts (62.5%), and in the single EXS Dacron graft. Four PTFE and three saphenous vein grafts failed subsequent to repeat intraoperative balloon angioplasty in three and graft extension in three and one graft interposition.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

Delay-related activity in the primate prefrontal cortex during sequential reaching tasks with delay.

To investigate how prefrontal neurons store multiple spatial locations simultaneously, neuronal activity during delay was analyzed while a monkey performed a delayed sequential reaching (DSR) task, in which the monkey was required to store both locations and the order of two sequentially presented targets during delay, and a delayed reaching (DR) task with single target. 38 out of 61 task-related neurons showed delay-related activity and were classified into three types. Type 1 (58%) showed delay-related activity depending upon the direction of the first reaching movement. Type 2 (21%) showed delay-related activity depending upon whether the reaching cue was presented at either left or right. Type 3 (21%) showed delay-related activity nonspecifically during all trials of both DSR and DR. Neurons with delay-related activity only in DSR trials were not observed. These results suggest that each prefrontal neuron may not hold information for the whole sequence of a complex movement during delay, but may hold partial information of that movement, such as one target location or one movement direction.

Animals↗