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Biomedical subjects

M Kitajima

Publications and source records attributed to M Kitajima.

At least 217 records · Page 12Linked to original sources
PubMed1997

Enhanced motility of the vagotomized canine stomach by electrical stimulation.

Functional impairment of the vagotomized stomach used as a substitute oesophagus seriously deteriorates the quality of life of patients following oesophageal cancer surgery. We speculated that if the enteric neurons of the reconstructed gastric tube survived functionally, the motility of the gastric tube could be facilitated and the recovery process after operation would improve as a consequence. In the present study we investigated whether direct electrical stimulation was effective for facilitating the motility of the canine vagotomized stomach. Dogs underwent truncal vagotomy by transabdominal approach and, in some cases, arteries to the upper stomach and the oesophagus were also ligated and resected to resemble the blood supply and surgical invasion of the reconstructed gastric tube. Electrical stimulation, a few minutes of positive rectangular current pulses, amplitude 20 V (or 15 mA), duration 0.5 ms and frequency between 0.2 and 7 Hz, was delivered on the greater curvature of the mid corpus. Changes in mechanical contractions were recorded using strain gauge force transducers. Electrical stimulation successfully enhanced the mechanical force of the phasic ring contractions of the vagotomized stomach in a frequency dependent manner. Aboral propagation and periodicity of the contractions, impaired by surgical procedures, were restored during stimulation. These excitatory effects were inhibited by atropine, hexamethonium and tetrodotoxin, suggesting that electrical stimulation acts on intramural cholinergic nerves that have survived functionally. These results suggest that electrical stimulation could be an effective method for improving the motility of the vagotomized stomach.

Animals↗
PubMed1997

Orbital pseudotumors: value of short inversion time inversion-recovery MR imaging.

PURPOSE: To evaluate magnetic resonance (MR) signal intensities of orbital pseudotumors on short inversion time inversion-recovery (STIR) images and to predict the effect of treatment. MATERIALS AND METHODS: Sequential MR examinations were performed in 17 patients with orbital pseudotumors, before and after treatment. All patients underwent MR imaging with T1- and T2-weighted spin-echo or fast spin-echo sequences, and STIR sequences with two 0.5-T systems. Quantitatively and qualitatively, the differences in signal intensities among three therapeutic response groups (good, mild, and no responses) were analyzed for each pulse sequence. RESULTS: Quantitatively, both contrast and contrast-to-noise ratio on STIR images corresponded well to the results of response to therapy for all background markers; contrast and contrast-to-noise ratio values in the good response group were the largest, while those in the no response group were the smallest (P < .0001). Qualitatively, the signal intensities of the lesions in the good response group were interpreted as hyperintense to the cerebral cortex in 14 (93%) or 11 (73%) of 15 lesions by two observers, respectively, while in the no response group, both observers assessed 16 (89%) of 18 lesions as hypo- or isointense to the muscle (P < .0001). CONCLUSION: STIR images showed a variety of signal intensities in the lesions, and the signal intensities on the STIR images helped predict the response to the therapy in orbital pseudotumors.

Adult↗
PubMed1997

[Cerebellar atrophy in Minamata disease: comparison with spino-cerebellar degeneration on MR images].

We evaluated atrophic patterns of the cerebellar vermis in seven patients with Minamata disease (MD) and nine patients with spino-cerebellar degeneration (SCD) on MR images. Twenty-five control subjects were also examined. The cerebellar vermis was divided into superior, middle, and inferior parts by the primary fissure and the prepyramidal fissure on the median sagittal T1-weighted MR image. The length and area of each part were measured. In the patients with SCD, there were no significant differences in the degree of atrophy among the three parts. However, MR images of the patients with MD showed more severe atrophy in the middle and inferior parts than in the superior part. Atrophy of the superior part was less frequently observed in MD patients.

Adult↗
PubMed1997

[Laparoscopic surgery for early gastric cancer--its advantage and pitfall].

We have successfully treated 50 patients with early gastric cancer by using two different laparoscopic procedures since March 1992. which are laparoscopic wedge resection of the stomach using a lesion-lifting method (n = 33) and laparoscopic intragastric mucosal resection (n = 17). The indication is as follows; (A) mucosal cancer, (B) < 25 mm, if the lesion is protruded type, (C) < 15 mm and Ul(-), if the lesion is depressive type. The advantages of these methods are; 1) minimally invasiveness. 2) sufficient surgical margin, 3) feasibility of detailed histology, 4) feasibility of perigastric lymph node dissection. In contrast, there are several problems to be solved, which are; 1) preoperative diagnostic accuracy of the depth of cancer invasion, 2) possibility of reoperation because of sm invasion or lymphatic or venous invasion in final histology, 3) possibility of postoperative stenosis after laparoscopic intragastric mucosal resection for the lesion near the cardia, 4) incidence of metachronous multiple gastric cancer.

Adult↗
PubMed1997

Laparoscopic local excision of the cecum for cecal creeping tumor.

Laparoscopic surgery is now widely accepted because of its many benefits. We have successfully performed laparoscopic curative resection in 72 patients with colon cancer or polyps. Of these patients, seven with cecal creeping tumor underwent laparoscopic local cecum excision (cecectomy). The creeping tumor is often found in the rectum and cecum. It is extremely difficult to remove endoscopically because of its shape and size. In addition, the recurrence rate after endoscopic mucosal resection is high. Therefore, laparoscopic cecectomy was thought to be a suitable procedure for such cases. This procedure was performed intracorporeally by using an ENDO-GIA and was less invasive than the extracorporeal procedure. These tumors, which showed local cancer limited to the mucosa or tubular adenoma with severe dysplasia in pathological findings, were resected completely. All patients tolerated liquids 1 day postoperatively and were discharged within 5 days. Our experience suggests that laparoscopic cecectomy has the potential to be useful for cecal creeping tumors.

Adenocarcinoma↗
PubMed1997

[The use of high resolution MR imaging for pre-treatment evaluation of breast cancer: detection of intraductal spread].

Thirty-two patients were examined in order to evaluate the role of high-resolution MRI in the treatment planning of breast cancer. A 1.5T Signa imager (GE Medical Systems) was used with dedicated receive-only breast coil. The pulse sequence based on RARE was used with the fat-suppression technique. After examining both breasts with larger FOV (30 cm), the affected breast alone was examined with smaller FOV (18 cm) and larger matrix (512 x 384) with Gd enhancement. Breast cancer showed more prominent and earlier enhancement compared with normal breast tissue. Linear or spotty continuous enhancement from the main tumor was considered to be suggestive of intraductal spread. Of 32 patients, 20 showed linear or spotty enhancement around the main tumor on MRI, and 15 of these 20 had intraductal spread. On the other hand, 12 out of 32 patients were considered to have little intraductal spread on MRI, and these findings corresponded to the pathological findings. Sensitivity, specificity and accuracy of detecting intraductal spread were 88%, 75% and 78%, respectively. In order to evaluate the extent of intraductal spread, further study using more precise correlation with pathology is necessary. High-resolution MRI was also considered to be useful for evaluating the presence of multifocal or multicentric focies or muscle invasion.

Adenocarcinoma↗
PubMed1997

T2 shortening in the visual cortex: effect of aging and cerebrovascular disease.

PURPOSE: To evaluate the effect of aging and cerebrovascular disease on T2 shortening in the visual cortex at MR imaging. METHODS: MR images of 72 neurologically normal subjects (45 men and 27 women, 35 to 92 years old) and 32 (13 men and 19 women, 54 to 92 years old) with cerebrovascular disease were evaluated retrospectively. On T2-weighted spin-echo images, the signal intensity of the visual, motor, and sensory cortices was divided into three grades and compared with the signal intensity of the frontal subcortical white matter. RESULTS: Decreased signal intensity (grade III) was rarely seen in the visual and sensory cortices of the neurologically normal subjects who were less than 60 years old. The signal intensity of the motor cortex decreased rapidly after the age of 50 years. At 61 to 70 years of age, 53% of these subjects had grade III intensity, and at age 71 years or older, 94% had reached grade III. The frequency of progression from grade I to grade III was lower in the visual cortex than in the motor cortex; 22% of these subjects had grade III appearance at age 61 to 70 years, and at age 71 years older, 56% had reached grade III. In patients with cerebrovascular disease who were older than 60 years of age, the frequency of grade III signal intensity in the visual cortex was almost equal to that in the neurologically normal subjects. CONCLUSIONS: T2 shortening in the visual cortex is frequently seen in neurologically normal older persons. These findings are compatible with a previously reported histochemical study of normal iron deposition in the visual cortex. Cerebrovascular disease has no effect on T2 shortening in the visual cortex.

Adult↗
PubMed1997

[Clinical criteria of chemosensitivity test].

Chemosensitivity test is useful in evaluating the appropriate cancer chemotherapy for solid tumors which are less sensitive to conventionally available antitumor agents. Most of assays used in clinics are in vitro assay, in which the cutoff concentration and contact time should be determined to mimic the clinical response of the chemosensitivity test. Since the antitumor effect of most of antitumor agents depends on their concentration x contact time, and the contact time will be determined according to the assay, the cutoff concentration will be calculated from the cumulative efficacy curve or 50% inhibitory concentration and in vivo response of human tumor xenografts in nude mouse. The clinical result obtained from chemosensitivity test was discussed.

Animals↗
PubMed1997

[Laparoscopically assisted surgery for Crohn's disease].

PURPOSE: Surgical treatment is often required by patients with Crohn's disease who have intestinal stricture or fistula. Minimally invasive laparoscopic surgery appears to be useful in such patients. Eight cases of intestinal stricture and/or fistula treated by laparoscopic surgery are reported. METHODS: In 1997, laparoscopic surgery was attempted and successfully completed in 18 patients Crohn's disease presenting with intestinal stricture and/or fistula, following strict nutritional therapy. Of the 8 patients with a fistula, one had an gastrocdic fistula, one had an ileovesical fistula, two had an colic fistula and three had ileoileal fistulas. Ileovesical, ileorectal and gastrocolic fistulas were divided with an intracorponeal automatic stapling device. Fourteen patients underwent ileocecal resection and four underwent ileal resection with laparoscopic assistance. RESULTS: Postoperative pain was mild, oral intake was started an average of 1.4 days after operation. The patients were discharged an average of 8 days after operation. No complication was identified. CONCLUSION: If Crohn's disease is treated adequately with conservative therapy, laparoscopic surgery is relatively easy, even when there are adhesions and fistulas. Since the incision is extremely small with this method, postoperative adhesions are minimized. This procedure has the advantage of allowing repeated laparoscopic surgery with minimal morbidity. Minimal invasiveness and rapid return to normal activity may make laproscopic surgery the treatment of choice for patients with Crohn's disease who require surgical treatment.

Adolescent↗
PubMed1997

[Surgical treatment for the upper and middle bile duct cancer].

A total of 45 patients with bile duct cancer, 13 patients predominantly with Bs bile duct cancer, 14 with Bm cancer, and 18 with Bim cancer, were chosen from 104 patients with bile duct cancer, not including gallbladder cancer or cancer of the papilla of Vater, who underwent surgical resection in our department between Sep 1974 and Nov 1996, and were evaluated with respect to surgical procedure, pathological findings, and outcome. The patients with Bs cancer were compared with 39 patients with cancer of the main hepatic duct junction who underwent hepatectomy, and the patients with Bim cancer were compared with another 20 patients with Bi bile duct cancer. The effect of combined resection of the vessels and hepatopancreatoduodectomy (HPD) on patients with advanced cancer was assessed. To attain a hw (-) margin, hepatectomy should be performed in patients with Bs bile duct cancer, unless localized. Bm and Bim bile duct cancer patients with negative margins had a relatively favorable outcome irrespective of surgical procedure. Resection of the vessels and HPD were useful in improving the resectability rate, but not in attaining longer survival.

Aged↗
PubMed1997

Detection of cytokine mRNA in unfractionated peripheral blood by reverse transcriptase polymerase chain reaction.

OBJECTIVE: To detect cytokine gene expression in unfractionated peripheral blood by reverse transcriptase-polymerase chain reaction (RT-PCR). DESIGN: Prospective study. SETTING: University hospital, Japan. SUBJECTS: 3 healthy volunteers and 3 severely infected patients. INTERVENTIONS: Peripheral blood was obtained and total RNA was extracted from 0.5 ml unfractionated whole blood with a 4 M guanidinium isothiocyanate mixture, 0.2 M sodium acetate, phenol, and chloroform. The mRNA was reverse transcripted, and interleukin-1 beta (IL-1beta) and tumour necrosis factor (TNF) cDNA were selectively amplified by synthetic primers with PCR. MAIN OUTCOME MEASURES: Establishment of cytokine gene expression in unfractionated peripheral blood. RESULTS: About 10 microg of total RNA was obtained from a 0.5 ml sample of blood. IL-1beta and TNF mRNA were not detected in blood from healthy volunteers, though they were detected in patients with severe infection. CONCLUSION: This method avoids artefactual gene activation and may be applicable to monitoring cytokine gene expression in various pathophysiological states.

Adult↗
PubMed1997

[Jejunal pouch interposition after total gastrectomy].

The results and procedures of interposed jejunal pouch after total gastrectomy for gastric cancer are reported. Basic requirements of reconstruction after total gastrectomy are 1) formation of a food reservoir, 2) maintenance of duodenal continuity, 3) avoidance of reflux esophagitis, 4) gradual emptying of reservoir into the small intestine. Since 1950's, several procedures of gastric substitutes have been reported. But they were not widely performed. Because scientific evaluation of the value of gastric substitutes was difficult and the operative procedures were time consuming and complicated. With an increasing ratio of early gastric cancer in 1990's, the importance of post-operative QOL, such as food intake and body weight maintenance, in patients after total gastrectomy has been recognized. Our procedure is a double lumen jejunal pouch distal to a interposed jejunum. The length of interposed jejunum is 20 cm and that of pouch is 10 cm. Using surgical staplers, this procedure is safe and simple. Jejunal pouch interposition leads to a satisfactory symptomatic and nutritional result in gastrectomized patients.

Gastrectomy↗
PubMed1997

MR changes in the calcarine area resulting from retinal degeneration.

PURPOSE: To study MR images for atrophic changes in the calcarine area resulting from retinal degeneration. METHODS: MR images from nine patients with retinal degeneration confirmed by ophthalmologic examination and from 30 healthy volunteers were reviewed. The causes of retinal degeneration were hereditary pigmentary degeneration of the retina (four patients), high myopia (two patients), and chorioretinal atrophy (three patients); all patients had visual disturbances and visual field abnormalities. To estimate the morphological changes of the calcarine area, the widths of the right and left calcarine fissures were measured on T1-weighted sagittal images and compared with images from age-matched control subjects. RESULTS: The calcarine fissures were significantly dilated in the patients with retinal degeneration. The anterior and middle points, which represent the peripheral visual field center, were more dilated than the posterior point. CONCLUSION: The MR findings suggested calcarine atrophy related to retinal degeneration. Transneuronal degenerative changes may occur in the calcarine area after retinal degeneration.

Aged↗
PubMed1997

[Salvage surgery for the T4 esophageal cancer following downstaging by neoadjuvant chemoradiotherapy].

The standard modality of the treatment for the patients with T4 esophageal cancer, whose prognosis still remains quite poor, is not established yet. Salvage surgery for the T4 esophageal cancer following downstaging by neoadjuvant chemo-radiotherapy has become to be available. During the period from 1992 to 96, 30 patients with the suspected T4 esophageal cancer underwent chemoradiotherapy, which consisted of two courses of CDDP/5-FU with-sequential or concurrent 50-60Gy radiotherapy. Among them eleven patients became to be resectable by means of thoracotomy and laparotomy and pathological CRs were obtained in either primary lesions or lymph nodes. The longest survival term following surgery is 36 months. Three patients died of cancer recurrence including the organ metastasis and one died from pyothorax without cancer due to severe immunosuppression attributable to chemoradiation. Our results warrants further studies of neoadjuvant chemoradiotherapy for the patients with T4 esophageal cancer.

Aged↗
PubMed1997

[Recent advances in antireflux surgery for gastroesophageal reflux diseases--from open surgery to laparoscopic surgery].

Gastroesophageal reflux diseases (GERD) are common in the western countries and have been well studied about diagnosis and treatment. Nissen technique (a complete wrap) and Toupet technique (a partial wrap) are usually transabdominal fundoplication. Hill technique is a transabdominal posterior gastropexy. Allison technique is a transthoracic reduction method of the herniated cardia back into the abdomen, but is not frequently employed today. Belsey Mark VI technique is a transthroacic anterior plication. Collis gastroplasty is an esophageal lenghening technique and is used with standard repairs (Nissen, Belsey, and Hill). Good result rate of above mentioned surgery are about 90%. Recently, laparoscopic Nissen/Toupet technique are a standard antireflex surgery because of minimal invasiveness and more than 90% of good results. After introducing laparoscopic surgery the indication of antireflex surgery for GERD can be changed because of quality of life of patients and medicoeconomical reasons.

Fundoplication↗
PubMed1997

Pancreatic lymph nodal and plexus micrometastases detected by enriched polymerase chain reaction and nonradioisotopic single-strand conformation polymorphism analysis: a new predictive factor for recurrent pancreatic carcinoma.

K-ras point mutations have been observed in approximately 90% of pancreatic carcinomas. We genetically analyzed cases of pancreatic regional lymph nodal and plexus micrometastases in invasive ductal carcinoma of the pancreas who were node negative or had metastases limited histopathologically to pancreaticoduodenal lymph nodes. These cases underwent curative resection in our institute. The utility of genetic analysis was compared with that of histopathological study, in terms of postoperative clinical outcome, as a predictive factor for recurrent pancreatic carcinoma. Samples for DNA extraction were obtained from formalin-fixed, paraffin-embedded specimens. A 0.5-microg quantity of DNA was subjected to enriched PCR and nonradioisotopic single-strand conformation polymorphism analysis. K-ras codon 12 mutations were detected in 83% (10 of 12) of invasive ductal carcinomas. In four cases, the genetic analysis of regional lymph nodal metastases and pancreatic plexus invasion of the pancreatic carcinoma yielded results concordant with those of histopathological analysis. In six cases, however, the metastases detected by genetic analysis were more advanced than was indicated by the histopathological examination. The survival rate of cases with metastases beyond the pancreaticoduodenal lymph nodes was significantly lower than that of cases with metastases limited to the pancreaticoduodenal lymph nodes or with no nodal involvement based on genetic analysis (P < 0.05). Intraoperative analysis of point mutations at K-ras codon 12 in the regional lymph nodes and the pancreatic plexus by enriched PCR/nonradioisotopic single-strand conformation polymorphism analysis is a highly accurate predictive factor for recurrent pancreatic carcinoma.

Adult↗