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S Nara

Publications and source records attributed to S Nara.

At least 19 recordsLinked to original sources
PubMed2002

Disorganization of honey-comb immunoreactive pattern of desmin and plectin in rat atrophic soleus muscle fiber induced by hindlimb suspension.

Immunoreactivity for desmin, plectin and alpha-actinin was investigated in rat atrophic soleus muscle fibers induced by hindlimb suspension between 1 and 4 weeks (hindlimb suspension group, HSG), and compared with that of the control group (CG). Some of the HSG for 4 weeks were allowed unrestricted cage activity for 2 weeks as the recovery group (RG). In the cross-sectioned muscle fibers of the CG, desmin and plectin showed honey-comb immunoreactive patterns extending throughout the sarcoplasm. Superimposed images by double immunofluorescence labeling showed overlapping of both immunoreactivities. In the longitudinally sectioned profiles, superimposed images of alpha-actinin and desmin were overlapped at the level of Z-discs. The focal disorganization of the above honeycomb immunoreactive patterns, followed by the reduction of the cross-sectional area (CSA) of atrophic soleus muscle fibers and the appearance of Z-streaming, uniquely arose in the HSG from the first week and extended throughout the sarcoplasm in proportion to the suspension period. Such honey-comb patterns of both desmin and plectin were already restored in the RG at 2 weeks, followed by the disappearance of Z-streaming, prior to the recovery of the CSA. These findings indicate that the disorganization of topological and structural relationships of desmin and plectin with Z-discs surrounding individual myofibrils is primarily evoked, which leads to Z-streaming of atrophic soleus muscle fibers, and that the restoration of the muscle activity results in an early arrangement recovery of desmin and plectin around myofibrils.

Animals↗
PubMed2002

Enhanced expression of endothelin-1 and endothelin-converting enzyme-1 in acute hypoxic rat aorta.

Deeply anesthetized male Wistar rats were perfused by Hanks' balanced salt solution bubbled with either 95%air and 5%CO2 (normoxic group) or 95%N2 and 5%CO2 (hypoxic group) from the thoracic aorta for 30 min, and the isolated abdominal aortae from both groups were used for electron microscopy, immunocytochemistry of endothelin (ET)-1 and ET-converting enzyme (ECE)-1, and in situ hybridization of preproET-1 mRNA. A remarkable increase in the number of Weibel-Palade (WP) bodies, storage sites of ET-1 and ECE-1, occurred in the hypoxic group when compared to the normoxic group. Immunoreactivities for ET-1 and ECE-1, and signals for preproET-1 mRNA were seen along the endothelia of both groups, but the intensities were significantly elevated in the hypoxic group. The increase in the number of ECE-1 immunoreactive gold particles was noticed especially in WP bodies in the hypoxic group. These findings indicate the enhancement of preproET-1 synthesis in the aortic endothelial cells as well as the acceleration of ET-1 processing in increased WP bodies in such cells in an experimentally hypoxic condition of the rat aortae.

Acute Disease↗
PubMed2001

Multiple primary cancers associated with esophageal carcinoma.

This study was conducted to examine the characteristics of esophageal cancers with primary synchronous or metachronous cancer in another organ. We retrospectively evaluated 744 patients who underwent esophagectomy for esophageal cancers between 1985 and 1998. The patients were divided into two groups according to whether they had multiple primary cancer (MPC) or nonmultiple primary cancer (NPC). Stage I cancer was significantly more frequent among patients with MPC than among those with NPC (P < 0.0001). Among patients with MPC, another primary cancer was found in the head and neck region in 70 (42.4%), in the stomach in 51 (30.9%), and in the colon, lung, breast, and other locations in the remaining patients. Of the 70 patients with another primary cancer in the head and neck region, 32 (45.7%) had pharyngeal cancer. Furthermore, the incidence of intraesophageal multiple cancer in the patients with primary cancer in the head and neck region was significantly higher than that in those whose other primary cancers were gastric cancer or in those with NPC (P = 0.0135. P < 0.0001). The 5-year survival rate of the patients with MPC was 51.28%, which was significantly higher than that of those with NPC (P = 0.019). In conclusion, a better knowledge of the relationships between esophageal carcinoma and cancers in other organs may lead to earlier detection of other primary cancers and improved therapeutic results.

Carcinoma, Squamous Cell↗
PubMed2001

Extra-anatomic bypass graft for management of axillary artery occlusion in pitchers.

OBJECTIVE: Our goal was to evaluate the long-term results of vein bypass grafts for axillary artery occlusion, specifically those placed extra-anatomically to prevent arterial injury in pitchers. METHODS: With the greater saphenous veins used as the selected conduit, arterial bypass grafts were routed anterior to the pectoralis minor muscle in four baseball pitchers who had occlusion of the axillary artery. We performed a follow-up in excess of 10 years with evaluations of the bypass grafts by ultrasonic duplex scan and magnetic resonance angiography. RESULTS: All four pitchers treated in this manner returned to the game and played for several seasons without a recurrence of the arterial injury. Long-term evaluation of the bypass grafts did not reveal any structural or functional disorder. CONCLUSIONS: Axillary artery occlusion in an athlete can be effectively treated with a vein bypass graft placed extra-anatomically, anterior to the pectoralis minor muscle. The greater saphenous vein should be considered the conduit of choice.

Adult↗
PubMed2001

Synthesis of calcitonin gene-related peptide (CGRP) by rat arterial endothelial cells.

We investigated the protein and mRNA expression of calcitonin gene-related peptide (CGRP) in endothelial cells of the rat thoracic aorta and femoral artery. Light microscopic immunocytochemistry revealed that immunoreactivity for CGRP was preferentially located in the endothelium of both vessels. Immunoelectron microscopy showed that CGRP-immunoreactive gold particles were preferentially localized on cisterns of the rough endoplasmic reticulum and on the Weibel-Palade (WP) bodies in the endothelial cells. Prepro CGRP mRNA signals were also detected on the endothelium. Our results are the first to demonstrate that endothelial cells of both elastic and large muscular arteries synthesize CGRP and store it, in part, in WP bodies, implying that CGRP may act as an endothelium-derived relaxing factor in these vessels.

Animals↗
PubMed2000

Hydroxy-Directed, SmI(2)-Induced Conversion of Carbohydrates into Carbocycles.

Polyoxygenated six-membered carbocycles were derived from carbohydrates with complete stereocontrol through hydroxy-directed coupling cyclization induced by SmI(2). For example, the cis-1,3-cyclohexanediol 3 is obtained from the D-glucopyranoside derivative 1 in excellent yield. The coupling cyclization is initiated by single-electron transfer from SmI(2) to the formyl group of the delta-hydroxy aldehyde 2 generated in an equilibrium process.

Journal Article↗
PubMed2000

Dietary zinc deficiency decreases glutathione S-transferase expression in the rat olfactory epithelium.

Zinc deficiency leads to olfactory and gustatory dysfunction, but little is known about the underlying molecular mechanism of this phenomenon. We examined the effect of dietary zinc deficiency on the rat olfactory epithelium. Immunoreactivities of glutathione S-transferase (GST) mu, neuron-specific enolase (NSE) and proliferating cell nuclear antigen (PCNA), and in situ hybridization of GST mu mRNA in the olfactory epithelia were examined under different dietary zinc intake conditions. Adult male rats were fed a zinc-deficient (ZD) diet (0.5 mg zinc/kg diet), whereas control rats, including pair-fed (PF) and zinc-adequate (ad libitum consumption, AL) groups, were fed a zinc-adequate diet (58 mg zinc/kg diet) for 7 wk. We also examined the effect of zinc replacement (ZR) by subsequently feeding half of the ZD group a zinc-adequate diet for 5 wk after the initial 7-wk deprivation. No significant differences in immunoreactivity for NSE in olfactory epithelial receptor cells or for PCNA in basal cells were noted among groups. Intense GST mu immunoreactivity and hybridization signals were observed in olfactory supporting cells of AL, PF and ZR groups, but very minimal or no such signal was noted in ZD rats. Our findings indicated that zinc deficiency reduces GST mu expression in the supporting cells of rat olfactory epithelia but does not affect receptor cell proliferation or maintenance.

Actins↗
PubMed2000

Synthesis and potato cell expansion-inducing activity of the stereochemically restricted bicyclic analogue of 7-epi-jasmonic acid.

The stereochemically restricted bicyclic analogue of 7-epi-jasmonic acid was synthesized from a known bicyclo[3.3.0]octane derivative. The enol triflate derived from the bicyclic compound was subjected to palladium-catalyzed coupling with allyltributyltin to give the desired carbon skeleton. Selective catalytic hydrogenation and subsequent acidic hydrolysis gave a new bicyclic analogue of 7-epi-jasmonic acid. The ACC conjugate of the bicyclic analogue was also synthesized. This ACC conjugate exhibited only slightly weaker potato cell expansion-inducing activity than that of the JA standard.

Biochemistry↗
PubMed2000

[Hepatic arterial infusion chemotherapy for liver metastasis from esophageal squamous cell carcinoma].

Since 1993, we have treated 9 patients with liver metastases from esophageal squamous cell carcinoma using hepatic arterial infusion chemotherapy (HAI). These patients underwent esophagectomy and reconstruction with a stomach roll, and without preoperative chemotherapy and/or radiotherapy, HAI was effective in 5 patients (56%) with a CR in 2 patients. Preceding systemic chemotherapy was done with 7 patients, and was effective in 3 of them. HAI was also effective in all of them. In 3 patients with hepatic arterial anomalies, the right gastroepiploic artery and right gastric artery feeding the stomach roll could be preserved after changing the hepatic arterial flow. Two stomach roll ulcers and one hepatic arterial stenosis were experienced due to the toxicity of HAI. However, the nausea, vomiting, diarrhea, and/or myelosuppression seen with the preceding systemic chemotherapy were not experienced. In spite of the technical difficulties in catheterization and toxicities to stomach roll, HAI is considered to be more effective and feasible than systemic chemotherapy.

Aged↗
PubMed1999

Endoscopic resection for submucosally invasive colorectal cancer: is it feasible?

BACKGROUND: Recent advances in colonoscopy have resulted in an increasing number of endoscopic resections of colorectal neoplasms. However, endoscopic resection of submucosal invasive cancer remains a controversial issue. METHODS: The subjects for this study were the surgically treated patients with submucosal invasive colorectal cancer. These patients were classified into two groups: those with versus those without preoperative endoscopic resection. Clinicopathologic features and prognosis were compared and analyzed. RESULTS: Fifty patients underwent surgery for submucosally invasive colorectal cancer. Numbers of patients with and without preoperative endoscopic resection were 22 and 28, respectively. In 36.4% of the patients, endoscopic resections were incomplete. Two patients in whom the preoperative endoscopic resections had revealed a positive cancer margin, had nodal metastasis. One of these patients also developed hepatic metastasis. Endoscopic findings such as diameter and shape were not indicative of either lymphatic or vascular invasion. There were no morbidities or mortalities associated with endoscopic resection or surgery. CONCLUSIONS: Preoperative endoscopic resection for colorectal submucosal cancer is feasible, provided the resection is complete. The indications for surgical treatment should be determined after pathologic examination.

Case-Control Studies↗
PubMed1998

Appendico-ileo-vesical fistula.

Appendico-vesical fistula is a rare condition. In total, 109 cases, most secondary to appendicitis, have been reported in the English-language literature. We report the first case, to our knowledge, of appendico-ileo-vesical fistula secondary to appendiceal diverticulitis. An enterovesical fistula was diagnosed by urine culture, cystoscopy, and computed tomography. The locations of enteric opening sites were demonstrated by barium enema and colonoscopy. Ileocecal resection and fistulectomy with primary reconstruction were performed. We believe that accurate pre- and intra-operative diagnosis is essential for cure. This case demonstrates the importance of barium enema and colonoscopic examinations in the diagnosis and treatment of complicated enterovesical fistula.

Adult↗
PubMed1998

Primary malignant lymphoma of superior vena cava.

A 78-year-old woman suffered from superior vena cava (SVC) syndrome. Computed tomography and angiography revealed a mass within the SVC. The SVC was resected via median sternotomy, followed by reconstruction using an artificial graft. The resected specimen showed a polypoid tumor within the SVC that had invaded the wall of the SVC. Histologic diagnosis was diffuse large-cell non-Hodgkin's lymphoma. Most surrounding lymph nodes showed reactive swelling, but one showed a partial microscopic metastasis. These pathologic findings indicated that the tumor was an SVC-originating malignant lymphoma. The patient is now alive and tumor-free 65 months after the operation.

Aged↗
PubMed1997

Thyroglossal duct carcinoma: a case report.

We describe a 47-year-old woman with a 13-year history of asymptomatic midline submental swelling. Cytologic examination of a fine-needle aspiration specimen from the solid mass revealed adenocarcinoma. The preoperative diagnosis was thyroglossal duct carcinoma. A Sistrunk procedure was performed and microscopic examination revealed papillary adenocarcinoma. The postoperative course was uneventful and there were no signs of local recurrence or metastasis at one year after surgery.

Carcinoma, Papillary, Follicular↗
PubMed1996

Intraoral free flap monitoring with a laser Doppler flowmeter.

The blood flow in 37 free flaps used for intraoral reconstruction was measured by laser Doppler flowmetry before and after elevation of the flap during surgery, immediately after the completion of reconstruction and on the 1st, 2nd and 3rd postoperative days (1 POD, 2 POD, 3 POD). Although the blood flow decreased temporarily after the flap elevation, it began to increase immediately after reconstruction and continued a gradual increase thereafter, reaching a peak on 2 POD. The flap survived in all cases where the blood flow on 3 POD was equal to or greater than that before flap elevation. Total necrosis of the flap occurred in one patient, and partial necrosis in another. In both patients, abnormal laser flow-metric measurements preceded the manifestation of the clinical signs. Using laser Doppler flowmetry to monitor free flaps both during surgery and for three days thereafter is thus a useful way of determining their viability.

Feasibility Studies↗
PubMed1996

Microsurgical composite reconstruction in head and neck and esophagus.

This paper describes-the indications for, the main points of the surgical technique, and the results of composite reconstruction using a combination of pediculated and free tissue units, which has allowed extensive and complex reconstruction following resection of malignant tumors in the head and neck region or in the esophagus. Composite reconstruction was indicated for synchronous or metachronous carcinomas in the head and neck region and the esophagus (Groups 1 and 2) or for secondary reconstruction of the esophagus (Group 3). In most cases, the gastric tube or colon was used as pediculated tissue, and the jejunum, forearm flap, or rectus abdominis flap were used as free tissue. Total necrosis of the transplanted jejunum occurred in two patients and leakage in five, most of whom were in Group 3. Although the prognosis was extremely poor in Groups 1 and 3 because of the advanced cancer stage, composite reconstruction permitted oral feeding, which proved beneficial from the viewpoint of the patient's quality of life.

Aged↗
PubMed1995

Synchronous reconstruction of the trachea and innominate artery in thyroid carcinoma.

A 50-year-old woman underwent combined resection and reconstruction of the trachea and the innominate artery synchronously for thyroid carcinoma. The pedicled thymus was interposed between the anastomosis of the trachea and the artery. The postoperative course was satisfactory. Synchronous reconstruction of the artery and trachea may thus prove to be safe, and interposition of the thymus flap may be useful in the prevention of secondary graft infection from the tracheal anastomosis.

Brachiocephalic Trunk↗