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M Karita

Publications and source records attributed to M Karita.

16 recordsLinked to original sources
PubMed1992

Application of ultrasonic probes prior to endoscopic resection of early gastric cancer.

The development of a new strip biopsy technique for endoscopic mucosectomy utilizing endoscopic saline injection and a double-channel endoscope permits the safe and simple resection of superficial type early gastric cancer which has been difficult to perform with conventional polypectomy techniques. Preresection assessment of the depth of invasion and postresection assessment of efficacy are important with regard to treatment of early gastric cancer, but conventional endoscopic ultrasonography employed for this purpose requires special equipment and involves intricate procedures. An ultrasonic probe which can be used endoscopically has recently been developed and is currently in the trial stage. The authors have conducted studies with respect to a 7.5 MHz radial scanning type Miniature Ultrasonic Probe as well as a 20 MHz manual linear scanning type Sonoprobe System. Experimental studies indicated that the former type is capable of delineating postresection ulcers, while the latter permitted delineation of tumors as hypoechoic images in 9 of 11 cases of early gastric cancer.

Adenocarcinoma↗
PubMed1991

Role of epidermal growth factor in protection and repair of gastric mucosal injury.

A role of epidermal growth factor (EGF) in protection and repair of gastric mucosal injury caused by p.o. administration of 0.6 N HCl was investigated in male Wistar rats. Previous to the study on the role of EGF in gastric mucosal protection and repair, changes of gastric mucosal EGF level was determined sequentially by RIA for 180 min after treatment with 0.6 N HCl and intraperitoneal injection of recombinant hEGF. Concentration of incorporated hEGF into the gastric mucosa reached the peak level at 30 min after injection of hEGF. On the other hand, the gastric endogenous EGF level fell remarkably immediately after treatment with 0.6 N HCl. Successively, an association with the mucosal levels of incorporated hEGF and gastric ulcer indices was investigated in the rats in which hEGF was injected intraperitoneally 30 min prior to or at the same time as oral administration of 0.6 N HCl. In conclusion, pretreatment with hEGF protected significantly against gastric mucosal injury with 0.6 N HCl, whereas simultaneous administration of hEGF could not protect against mucosal injury but indicated possible stimulation of the repair process from acute gastric mucosal damage.

Animals↗
PubMed1991

New small animal model for human gastric Helicobacter pylori infection: success in both nude and euthymic mice.

In order to develop an experimental rodent model, we administered 2 ml (10(8) organisms/ml) broth culture of any of four human isolated strains of Helicobacter pylori by the oral route on a one-time basis to both BALB/c nude and BALB/c euthymic mice. After 20-wk examination, we have successfully demonstrated that the gastric mucosa of nude mice was continuously, and that of euthymic mice, temporarily (for 2 wk), colonized by orally administered, freshly isolated strains obtained from humans with gastritis, gastric ulcer, and duodenal ulcer, but never by the established strain. After colonization, gastritis and duodenitis were produced, and the presence of bacteria in gastric mucus was pathologically proved in all infected animals. We have confirmed that such colonization is always established when a large dose of a freshly isolated strain of H. pylori is administered at one time. We believe that this is the first reported rodent model of H. pylori-associated gastritis.

Animals↗
PubMed1989

[Definition of the adaptation of endoscopic surgery for early gastric cancer. Special examination on the relationship between the histological differentiation of the intramucosal gastric cancer and the lymph node metastasis].

Out of five hundred and nineteen surgically resected lesions which were histologically shown to be intramucosal gastric cancer, 247 were well differentiated, 98 were moderately differentiated, and 176 were poorly differentiated lesions. The incidence of lymph node metastasis in the 247 well differentiated, 98 moderately differentiated, and 176 poorly differentiated intramucosal adenocarcinomas were 0.8% (= 2/247), 2.1% (= 2/98), and 8% (14/176), respectively. The cumulative survival rate of 5 years after gastrectomy was 94.2% for the 247 well, 93.3% for the 98 moderately, and 93.7% for the 176 poorly differentiated adenocarcinomas. A pathological study on the atypism of the gland of the cancer and the condition of the proprial space under the cancer cells was conducted on 100 lesions of well differentiated adenocarcinomas in order to define the criteria of non-surgical endoscopic removal resection for early gastric cancer. Out of the 100 lesions mentioned above, there were only two well differentiated adenocarcinomas with lymph node metastasis in which the boundary between the epithelium of the cancer and the proprial space under the cancer was very unclear and the interstitial space in the propria under the cancer was very small. On the other hand, we have resected 73 intramucosal gastric cancers using the endoscopic surgical method called strip biopsy since 1984, and have followed up these cases. The cancers resected by strip biopsy, and were histologically intramucosal well differentiated adenocarcinomas shown to have a moderately maintained interstitial space under the cancer cells. And, up to the present, there has been no incidence of recurrence after strip biopsy for the 73 lesions mentioned above. According to these results, we have defined the criterion for early gastric cancer endoscopic surgery, as follows. Intramucosal cancer which is shown to be well differentiated adenocarcinoma with a moderately maintained interstitial space under the cancer cells is considered to be sufficient for non-surgical endoscopic resection.

Aged↗
PubMed1988

[Endoscopic therapy of early gastric cancer by strip biopsy].

Strip biopsy is carried out in accordance with the principle of endoscopic injection and polypectomy. By using strip biopsy, the full thickness of the mucosa is removed, including the submucosal layer, largely without risk, even in cases of depressed or flat lesions. We have applied this procedure to the therapy of early gastric cancer. Its most valuable aspect is that the resected tissue is collected and the efficacy of the therapy can be evaluated from both macroscopic findings and histological sections. We have applied strip biopsy in 133 cases involving 137 lesions of 8 early gastric cancer, of which 65.0% were totally resected using only the strip biopsy technique. Other cases were treated surgically or subjected to additional endoscopic therapy. sixteen cases were confirmed to have been perfected resected by stomach surgery. Another 71 patients who were not candidates for surgery because of their physical condition have been followed endoscopically for 2 to 48 months, but there has not been any recurrence. On the basis of this study, we believe that the strip biopsy therapy of early gastric cancer should be evaluated in addition to surgical therapy, especially in cases of small lesions localized only in the mucosa.

Biopsy↗
PubMedDate not supplied

Endoscopic therapy for early colon cancer: the strip biopsy resection technique.

Strip biopsy is an endoscopic tissue resection technique in which a lesion and its surrounding tissues are first elevated using physiological saline. The saline solution is injected into the submucosa at the site of the lesion with the help of needle forceps. A snare is placed around the elevated tissue, which is then resected endoscopically by electrocoagulation. The specimen obtained includes both submucosal and mucosal tissues. The authors used this technique to resect a total of 71 lesions of the colon. They were classified histologically as 21 adenocarcinomas, 46 adenomas, 3 metaplastic polyps, and 1 juvenile polyp. All lesions were confirmed to be entirely intramucosal by histological examination. The strip biopsy technique permits resection of tissue down to the submucosal layer regardless of the morphological type of the lesion. This suggests that strip biopsy is an effective new form of endoscopic treatment for early colon cancer.

Adenocarcinoma↗