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Biomedical subjects

N Ando

Publications and source records attributed to N Ando.

At least 19 recordsLinked to original sources
PubMed2005

The use of endoscopic ultrasound-guided fine-needle aspiration for investigation of submucosal and extrinsic masses of the colon and rectum.

BACKGROUND AND STUDY AIM: Ensdoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has been reported as a useful technique for histological diagnosis of submucosal or extrinsic gastrointestinal and pancreatic lesions. The aim of this study was to evaluate the use of EUS-FNA for the diagnosis of lesions either within or adjacent to the wall of the colon and rectum. PATIENTS AND METHODS: A total of 22 patients with a lesion within the wall of, or adjacent to, the colon or rectum underwent EUS-FNA. They were divided into two groups: patients who had previously had a malignancy (the "previous +ve" group, n = 11), and patients who had not previously had a malignancy (the "previous -ve" group, n = 11). In the four patients who had lesions located proximal to the sigmoid colon, EUS-FNA was performed using a guide wire and overtube. The success rates for adequate tissue sampling and for detecting malignant and benign masses by EUS-FNA were evaluated and the success rate for detection was compared with the success rate of EUS and computed tomography. RESULTS: Sufficient tissue for evaluation was obtained from 21 of the 22 patients (95.5 %). The overall rate of detection of malignant and benign masses was 95.5 % (21/22) for EUS-FNA and 81.8 % (18/22) for pre-EUS-FNA imaging investigations. Of the 11 patients in the previous +ve group, ten were diagnosed with recurrences of primary malignancies; of the 11 patients in the previous -ve group, four were diagnosed with primary malignancies and seven were diagnosed with benign lesions. There were no complications related to the EUS-FNA procedure. CONCLUSIONS: EUS-FNA is a safe technique which is useful in the planning of treatment for patients who have a mass within the wall or adjacent to the wall of the entire length of the colon or rectum.

Adult↗
PubMed2005

Alterations of p53, cyclin D1 and pRB expression in the carcinogenesis of esophageal squamous cell carcinoma.

Many molecular alterations occur in esophageal carcinogenesis; however, little is known about the molecular genetic events responsible for the development of carcinoma. We investigated the expression of ki67, p53, cyclin D1 and pRB in 105 biopsy specimens using immunohistochemistry from iodine unstained lesions as indicators of carcinogenesis of the esophagus. Also, the genetic alternation of esophageal dysplasia from patients with accompanying esophageal squamous cell carcinoma (ESCC) was examined to study the evidence for field carcinogenesis in the esophagus. The expression of p53, cyclin D1 and pRB was detected in 31, 0 and 51.7% respectively of mild dysplasia; 40, 0 and 70% of moderate dysplasia; 40, 20 and 70% of severe dysplasia; and 48, 32 and 80% of carcinoma specimens. p53 expression was significantly increased in mild dysplasia, whereas cyclin D1 and pRB expression were significantly increased in carcinoma as compared to both normal epithelium and esophagitis. The ki67 LI and the rate of p53 expression were significantly higher in dysplasia with ESCC than in dysplasia without ESCC. Ki67, p53, cyclin D1 and pRB expression may be useful biomarkers for assessing the risk of developing esophageal cancer. Dysplasia observed at screening for secondary lesions has a highly malignant potential and careful follow-up studies are required.

Carcinoma, Squamous Cell↗
PubMed2004

Usefulness of magnifying endoscopy in the diagnosis of early gastric cancer.

BACKGROUND AND STUDY AIMS: We investigated the characteristic findings of early gastric cancer revealed by magnifying endoscopy, and clarified their relationship with histopathological features. PATIENTS AND METHODS: A total of 74 patients with early gastric cancer underwent magnifying endoscopy ( x 80) between March 2000 and December 2001. The endoscopic findings demonstrated 11 elevated-type carcinomas and 63 depressed-type, and histological examination showed 56 differentiated carcinomas and 18 undifferentiated carcinomas. The histopathological results were compared with findings from magnifying endoscopy regarding minute surface structure and microvessels. RESULTS: We were able to roughly classify the minute surface structure of early gastric cancer as shown by magnifying endoscopy into three patterns, as follows: (i). a small regular pattern of sulci and ridges; (ii). an irregular pattern of sulci and ridges; and (iii). a lack of visible structure. Abnormal microvessels observed in cancerous lesions were classified according to two patterns: irregular minute vessels and variation of vessel caliber. The small regular pattern of sulci and ridges was significantly more frequently observed in differentiated carcinoma (30/56, 53.6 %) than in undifferentiated carcinoma (2/18, 11.1 %). Lack of visible structure and irregular minute vessels were significantly more frequently observed in undifferentiated carcinoma (44.4 % and 77.7 %) than in differentiated carcinomas (5.4 % and 51.8 %). CONCLUSION: The minute surface structure and microvessels observed by magnifying endoscopy were related to histopathological findings. Magnifying endoscopy is valuable for predicting the histological nature in the diagnosis of early gastric cancer.

Adenocarcinoma↗
PubMed2003

Impaired Delta Np63 expression associates with reduced beta-catenin and aggressive phenotypes of urothelial neoplasms.

p63, a homologue of the p53 gene, is considered to be essential for the normal development of stratified epithelia including urothelium. To examine possible roles of p63 in urothelial tumorigenesis, p63 expression was systematically examined in normal urothelium, low-grade papillary noninvasive (LPN) urothelial tumours, and high-grade or invasive carcinomas, using either an isoform-nonspecific or a Delta N-isoform-specific antibody. Expression profiles of p63 were also analysed in cultured cells. Immunoreactivity with the two antibodies was virtually identical in tissue samples examined. Basal and intermediate cell layers of normal urothelium showed intense nuclear p63 immunostaining. This normal staining pattern was preserved in a majority of LPN tumours, whereas it was frequently impaired in high-grade or muscle-invasive carcinomas. At the mRNA level, Delta Np63 expression predominated over TAp63, and amounts of Delta Np63 mRNA correlated with p63 immunoreactivity, confirming that Delta Np63 accounts for p63 expressed in urothelial tissues. In cultured cells, Delta Np63 was also expressed in low-grade tumour cells as well as normal urothelial cells, but undetectable in high-grade aggressive carcinoma cells. Interestingly, impaired Delta Np63 expression significantly associated with reduced beta-catenin expression that was possibly related to progression of urothelial neoplasms. Thus, impaired Delta Np63 expression characterises aggressive phenotypes of urothelial neoplasms.

Base Sequence↗
PubMed2003

Frequency of spinocerebellar ataxia mutations in the Kinki district of Japan.

OBJECTIVES: To determine the frequencies of spinocerebellar ataxias (SCAs) in the Kinki district, the western part of the main island of Japan. MATERIAL AND METHODS: One hundred and forty-three families with dominantly inherited ataxia and 220 patients with apparently sporadic cerebellar ataxia were examined for the SCA1, SCA2, SCA3/Machado-Joseph disease (MJD), SCA6, SCA7, SCA8, SCA12 and dentatorubral-pallidoluysian atrophy (DRPLA) mutations. RESULTS: Among the dominant families, SCA1 accounted for 3%, SCA2 for 4%, SCA3/MJD for 24%, SCA6 for 31% and DRPLA for 12%. Neither SCA7 nor SCA12 mutations were detected. Among the apparently sporadic patients, 15% were found to have expanded triplet repeats. Of these, the SCA6 mutation was most frequently detected. CONCLUSION: SCA6 is the most common SCA in the Kinki district of Japan. Comparison of our results with those from other regions of Japan and different countries shows geographic and ethnic variation in the frequency of SCAs.

Adult↗
PubMed2002

A dual-channel FM transmitter for acquisition of flight muscle activities from the freely flying hawkmoth, Agrius convolvuli.

Moths can perform various flight maneuvers by the contraction of some direct and indirect flight muscles. Multi-channel recording from these flight muscles and analysis of their interaction is very important for understanding insect flight motor system. In this study, we developed a dual-channel FM transmitter for acquisition of muscle potentials, with which a male hawkmoth (Agrius convolvuli) could fly freely and perform pheromone triggered zigzag flight in a wind tunnel. The transmitter weighs only 0.25 g including single battery, has a 5 m receivable range and works for more than 30 min. Doubling channels was achieved by providing two oscillators (the carrier frequencies were 82 and 85 MHz), and interference between them was overcome by buffer amplifiers and independent reference electrodes for each channel. With this transmitter, we could acquire muscle potentials from some direct and indirect muscles during free flight. Combined with simultaneous high-speed video analysis, we observed distinct changes of motor patterns during takeoff. Our radio-telemetric system allows acquisition of actual information from freely flying moths; such information will lead to further progress in the study of insect flight.

Animals↗
PubMed2002

Simultaneous multiple early cancers of esophagus and stomach treated by endoscopic mucosal resection.

Endoscopic mucosal resection (EMR) has been accepted as a completely curative treatment of gastrointestinal mucosal cancers. With advances in diagnostic techniques, the tendency to detect simultaneous multiple primary cancers is increasing. Patients with another cancer coexisting with esophageal cancer have had a poor prognosis, but if both cancers are detected in the early stage, complete treatment consisting only of endoscopic surgery, with a good prognosis, is expected. We describe two cases of simultaneous multiple early cancers of the stomach and esophagus, treated by EMR.

Adenocarcinoma↗
PubMed2001

Oxidation-active flavin models: oxidation of alpha-hydroxy acids by benzo-dipteridine bearing metal-binding site in the presence of divalent metal ion and base in organic solvents.

The oxidizing ability of benzo-dipteridine bearing a bipyridin-6-ylmethyl moiety (4) was found to be increased with Zn(2+) by approximately 10(3)-fold for sulfite addition in MeOH and approximately 10(2)-fold for oxidation of an NADH model in MeCN. It was found for the first time that 4 is able to oxidize alpha-hydroxy acids to alpha-keto acids in the presence of a divalent metal ion such as Zn(2+), Co(2+), and Ni(2+) and an amine base in MeCN or t-BuOH, whereas benzo-dipteridine having a bipyridin-5-ylmethyl moiety (3) is unable to oxidize them under the same conditions. The oxidation reaction was kinetically investigated including the kinetic isotope effect for deuterated mandelic acids (k(H)/k(D) = 2.1-3.7) and the Hammett plots for substituted mandelic acids (V-shaped plots). In the reaction of alpha-substituted alpha-hydroxy acids such as alpha-methyl mandelic and benzylic acids with 4, novel oxidative decarboxylation was found to take place, giving acetophenone and benzophenone, respectively. The oxidation mechanism for mandelic acid was proposed to proceed via a ternary complex of 4.Zn(2+).PhCH(OH)CO(2)(-), in which alpha-oxyanion of mandelate attacks C(4a)-position of 4 to form an adduct followed by 1,2-elimination to afford benzoyl formate and 2e-reduced 4. The roles of the metal ion were proposed as follows; (i) activation of 4, (ii) substrate-binding site, and (iii) activation of the bound alpha-hydroxy acid by lowering pK(a)'s of alpha-OH and alpha-CH. This is a first example that a flavin model oxidizes alpha-hydroxy acids in the presence of a metal ion.

Journal Article↗
PubMed2001

Phase II evaluation of protracted infusion of cisplatin and 5-fluorouracil in advanced squamous cell carcinoma of the esophagus: a Japan Esophageal Oncology Group (JEOG) Trial (JCOG9407).

BACKGROUND: Surgery for advanced esophageal carcinoma has its limits as regards aggressiveness and therapeutic effect, therefore effective multimodality treatment is required to obtain better survival. The objective of this study was to evaluate whether daily continuous infusion of CDDP could achieve a higher clinical response rate with less toxicity than its drip infusion in the previous phase II study that we had conducted. METHODS: Patients with primary extensive or relapsed esophageal carcinoma after esophagectomy, which had distant organ metastasis and histologically proven SCC, were eligible for this study. A dose of 20 mg/m(2) of cisplatin and 800 mg/m(2) of 5-fluorouracil was given by continuous infusion for 24 h on days 1-5. This treatment was repeated every 4 weeks for up to four cycles. A total of 36 men and six women with a median age of 64 (range 39-75) years were registered and 36 patients were eligible. RESULTS: The overall response rate of the registered patients was 33.3% (12/36) and the median response duration was 175 days. Median survival time was 201.5 days and the 1-year survival rate was 27.8%. Change from bolus to continuous infusion of cisplatin affected neither the type nor the degree of toxicity. CONCLUSION: Daily continuous infusion of cisplatin was not associated with higher response or lower toxicity than those seen with the high-dose bolus or multibolus treatment regimens. We conclude that this regimen in this setting is not worthy of further phase III trials. JEOG is now evaluating other drug combination regimens.

Adult↗
PubMed2001

Corrosion behavior of dental alloys coupled with titanium. Part 2. The area ratio dependence in five solutions.

Sixteen alloys and five pure metals were used and the open circuit potentials (OCP) and the coupled potentials with titanium were measured in five kinds of solutions. All alloys and metals showed the maximum OCP in 1.3% lactic acid solution, and the minimum in 0.01% sodium sulfide solution. The coupled potential depended on the area ratio (alloy/titanium). This dependence was different in every solution. From the area ratio dependence of the coupled potential, the potassium fluoride solution was thought to be active with pure titanium. In contrast, sodium sulfide solution was thought to be active with the alloys and the metals. The effect of the co-existence of pure titanium was very small in the sodium sulfide solution.

Corrosion↗
PubMed2001

[Appropriate extent of lymphadenectomy in esophageal cancer].

Because of the high frequency and widespread distribution of lymph node metastasis in esophageal cancer, three-field dissection was introduced in the early 1980s. Although improvement in the long-term survival rate of patients who undergo three-field dissection has been reported, the clinical significance of cervical lymphadenectomy is still controversial because the effect of improved upper-mediastinal lymphadenectomy in these patients cannot be excluded. Recently, the sentinel node (SN) concept has been validated in gastrointestinal cancers including esophageal cancer using the radio-guided method. Aberrant drainage routes from the primary lesion have frequently been observed in esophageal cancer and are detectable by radio-guided SN mapping. SN navigation is useful to identify SNs as the functional first basin to evaluate the regional lymph node status and to determine the indications for extensive lymphadenectomy in patients with esophageal cancer. Individualized surgical management of patients with esophageal cancer is essential to improve the quality of life of patients and long-term results.

Esophageal Neoplasms↗
PubMed2001

Laparoscopic detection of sentinel lymph nodes in gastrointestinal cancer: a novel and minimally invasive approach.

Although the sentinel node (SN) concept has been validated in malignant melanoma and breast cancer, the application of this concept for other solid tumors, including gastrointestinal (GI) cancer, is still controversial. We have demonstrated the feasibility of radioguided SN mapping during laparotomy in patients with esophageal, gastric, and colorectal cancers. In 188 patients, the SNs identified by this technique had an overall diagnostic accuracy of 96% for regional lymph node metastasis. Aberrant drainage sites that have been called skip metastasis from the primary lesion were detectable using this method. More recently, we have undertaken SN mapping during laparoscopic surgery. A combination of radiotracer and blue dye optimized the identification of SNs that drained GI cancers. Our preliminary data indicate that laparoscopic mapping of the SN is a sensitive intraoperative technique for identifying lymph node micrometastasis, and we believe that it will become an important component of a minimally invasive approach to early-stage GI cancers.

Colonic Neoplasms↗
PubMed2000

Telomerase activity as an indicator of malignant potential in iodine-nonreactive lesions of the esophagus.

BACKGROUND: Iodine-nonreactive lesions of esophageal epithelium often are associated with dysplasia and carcinoma. The authors examined the usefulness of telomerase activity as an indicator for esophageal carcinogenesis in such lesions. METHODS: Telomerase activity was measured using the telomeric repeat amplification protocol assay in 18 samples of iodine-nonreactive lesions apart from the primary tumor in surgically resected specimens obtained from patients with esophageal squamous cell carcinoma (ESCC) and 55 endoscopic punch biopsies of iodine-nonreactive lesions obtained from 25 patients with ESCC and 30 patients who had undergone endoscopic examination for other reasons. RESULTS: Ten of 18 iodine-nonreactive samples (56%) obtained from surgically resected specimens showed telomerase activity. In all ten telomerase positive samples, carcinoma in situ (CIS) was observed in iodine-nonreactive mucosa by light microscopy. In eight telomerase negative samples, no tumor tissue was observed in iodine-nonreactive lesions. In a parallel study, telomerase activity was detected in 28 of 55 endoscopic punch biopsy specimens (51%). CIS was observed in 25 of 28 iodine-nonreactive lesions with positive telomerase activity (89%), and tumor tissue was not observed in the other 3 samples (11%), which included 2 cases of severe dysplasia and 1 case of moderate dysplasia. No tumor tissue was observed in any of the 27 telomerase negative samples. CONCLUSIONS: Positive and negative telomerase activity was found to be correlated with the presence and absence, respectively, of immortalized tumor cells in iodine-nonreactive lesions. The measurement of telomerase activity in iodine-nonreactive lesions independently contributes to the selection of an appropriate therapeutic strategy.

Adult↗
PubMed2000

Increased fibrinolytic activity and body cavity coagula.

When a large volume of coagulum remains in the body cavity after trauma or surgery, secondary fibrinolysis occurs, which disturbs the hemostatic balance and results in rebleeding. To better understand this condition, we conducted a clinical study on patients with and without coagula and an experimental study on fibrinolytic activity in a rat model. The results of the clinical study showed that when coagula existed in the body cavity, the blood levels of the fibrin degradation products D-dimer and fibrinopeptide Bbeta15-42 remained high compared with when subjects were under similar stress but without the presence of coagula. In the experimental studies, fibrinolytic activity of the omentum, measured by the fibrin plate method, was higher in rats with hemoperitoneum. This suggests that increased fibrinolytic activity may lead to rebleeding from the area of transient hemostasis when coagulum is present in the body cavity.

Adolescent↗
PubMed2000

Gemfibrozil metabolite inhibits in vitro low-density lipoprotein (LDL) oxidation and diminishes cytotoxicity induced by oxidized LDL.

We hypothesized that M1, a metabolite of gemfibrozil, may have antioxidant properties because of its hydroxylated phenol ring, 5-(4-hydroxy-2,5-dimethyl-phenoxy)-2,2-dimethyl pentanoic acid. The susceptibility of low-density lipoprotein (LDL) to oxidative modification was investigated by a method using 2,2-azobis(4-methoxy-2,4-dimethylvaleronitrile [MeO-AMVN]) or Cu2+ as previously reported. Conjugated dienes (CDs), lipid hydroperoxide (LPO), and thiobarbituric acid-reactive substances (TBARS) were measured to evaluate the degree of LDL oxidation. Oxidized LDL (OxLDL), which is used for cytotoxicity studies, was prepared by the dialysis method using Cu2+ as the oxidation inducer. Cytotoxicity induced by OxLDL was studied in J774 macrophages by colorimetric assay using 3-[4,5-dimethyl-thiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT assay). The oxidative modification of LDL was inhibited by M1 in a dose-dependent manner. The antioxidant effect of M1 on LDL oxidation was diminished by dialysis of the LDL incubated with M1 against phosphate-buffered saline (PBS), suggesting that M1 is hydrophilic rather than lipophilic. M1 diminished the cytotoxicity induced by OxLDL, although it was milder versus probucol. These data suggest that this gemfibrozil metabolite has an antioxidant effect on LDL, and thus M1 may contribute to the antiatherogenic effects of gemfibrozil.

Antioxidants↗
PubMed2000

The role of the sentinel lymph node in gastrointestinal cancer.

Evaluation of the clinical significance of the sentinel node concept in GI cancer has just begun. The authors' preliminary data, using intraoperative radiation techniques and the gamma probe, suggest that it is worthwhile to continue the evaluation of this procedure to determine its role in an accurate staging and a minimally invasive approach to GI cancers.

Feasibility Studies↗
PubMed2000

Improvement in the results of surgical treatment of advanced squamous esophageal carcinoma during 15 consecutive years.

OBJECTIVE: To document the clinicopathologic characteristics and survival of patients undergoing esophagectomy for squamous carcinoma of the thoracic esophagus, and to examine the factors contributing to improvements in outcome noted in patients with advanced carcinoma. SUMMARY BACKGROUND DATA: Japanese and some Western surgeons recently have reported that radical esophagectomy with extensive lymphadenectomy conferred a survival advantage to patients with esophageal carcinoma. The factors contributing to this improvement in results have not been well defined. METHODS: From 1981 to 1995, 419 patients with carcinoma of the thoracic esophagus underwent esophagectomy at the Keio University Hospital. The clinicopathologic characteristics and survival of patients treated between 1981 and 1987 were compared with those of patients treated between 1988 and 1995. Multivariate analysis using the Cox regression model was carried out to evaluate the impact of 15 variables on survival of patients with p stage IIa to IV disease. Several variables related to prognosis were examined to identify differences between the two time periods. RESULTS: The 5-year survival rate for all patients was 40.0%. The 5-year survival rate was 17.7% for p stage IIa to IV patients treated during the earlier period and 37.6% for those treated during the latter period. The Cox regression model revealed seven variables to be important prognostic factors. Of these seven, three (severity of postoperative complications, degree of residual tumor, and number of dissected mediastinal nodes) were found to be significantly different between the earlier and latter periods. CONCLUSIONS: The survival of patients undergoing surgery for advanced carcinoma (p stage IIa to IV) of the thoracic esophagus has improved during the past 15 years. The authors' data suggest that this improvement is due mainly to advances in surgical technique and perioperative management.

Adult↗