Two cases of aorto-gastrointestinal fistula.

We report two cases of aorto-gastrointestinal fistula. Case 1, a 60-year-old man, suffered from repeat hematemesis. He was preoperatively diagnosed as aortoesophageal fistula with thoracic aortic aneurysm and was successfully treated by graft replacement of the aneurysm. Case 2, a 73-year-old man, presented with massive gastrointestinal bleeding, yet repeat endoscopical examination did not reveal the origin of the bleeding. He died of catastrophic hematochezia. The pathological findings at autopsy revealed an aortoduodenal fistula. These two cases suggested the importance to consider an aorto-gastrointestinal fistula in the differential diagnosis of patients presenting gastrointestinal hemorrhage.     

Future directions in biomaterials

Biomaterials have made a great impact on medicine. However, numerous challenges remain. This paper discusses three representative areas involving important medical problems. First, drug delivery systems; major considerations include drug-polymer interactions, drug transformation, diffusion properties of drugs and, if degradation occurs, of polymer degradation products through polymer matrices developing a more complete understanding of matrix degradation in the case of erodible polymers and developing new engineered polymers designed for specific purposes such as vaccination or pulsatile release. Second, cell-polymer interactions, including the fate of inert polymers, the use of polymers as templates for tissue regeneration and the study of polymers which aid cell transplantation. Third, orthopaedic biomaterials, including basic research in the behaviour of chrondrocytes, osteocytes and connective tissue-free interfaces and applied research involving computer-aided design of biomaterials and the creation of orthopaedic biomaterials.     

Responsiveness of gynecological malignancies to oral antitumor agents in subrenal capsule assay and individualization of oral adjuvant chemotherapy

A subrenal capsule assay (SRCA) was performed to test the sensitivity of 45 gynecological malignancies, including 24 cervical and 15 ovarian carcinomas, to oral antitumor agents, UFT, cyclophosphamide (CPM) and carboquone (CQ). Additionally, using a human endometrial carcinoma (Ishikawa carcinoma), the utility of SRCA in oral adjuvant chemotherapy was also investigated. Thirty-six of 45 cases (80.0%) were found to be evaluable. Regardless of the origin or of the histological type, each gynecological tumor showed a different degree of sensitivity. The results suggested that it is necessary to choose an oral antitumor agent according to the degree of sensitivity in oral adjuvant chemotherapy. In an experimental study with an implanted tumor, 14 of 20 mice (70.0%) developed a recurrent tumor in the control group. Compared to this, the recurrence rates for tumors in mice treated with CPM, CQ and UFT were 10.0% (p less than 0.001), 25.0% (p less than 0.01) and 30.0% (p less than 0.02), respectively. All these agents were considered to be effective in preventing tumors from recurring. In SRCA, the implanted tumor was sensitive to CPM and CQ, but not sensitive to UFT. These data suggested that SRCA is useful in predicting the effect of dose-dependent agents in oral adjuvant chemotherapy, although, with UFT, a time-dependent agent, it is not clear whether SRCA is appropriate for estimating the usefulness of its agent.     

Evaluation of the efficacy of photodynamic therapy on experimental hepatocellular carcinoma--using local injection of photosensitizer

The effect on photodynamic therapy (PDT) of using pheophorbide-a as a photosensitizer and Nd: YAG laser (Q-switch) was evaluated. Two hundred micrograms (0.1 ml) of pheophorbide-a was injected into tumors that had been subcutaneously implanted into the backs of nude mice (BALB/c-nu). Interstitial Nd: YAG laser irradiation (Q-switch; mean power 0.5 W, duration 10 min.) was performed 72 hours after pheophorbide-a injection. Forty-eight hours after laser irradiation, the areas of tumor necrosis were measured; these were larger in the group with the injection of pheophorbide-a than in those without. The areas of tumor necrosis after Nd: YAG laser irradiation at a higher mean power (Q-switch; mean power 2 W, control temperature 43-43.5 degrees C, duration 10 min.) were also measured. Again, the areas were larger in the group injected with pheophorbide-a. These results show that the injection of pheophorbide-a and interstitial irradiation using Nd: YAG laser induce a photodynamic reaction, and that this combination is useful in the treatment of deep-seated tumors.     

Post-transfusion hepatitis in operated uterine cancer patients

We examined the incidence of non-A, non-B hepatitis (NANB) in post-transfusion hepatitis in uterine cancer patients treated by surgery at our hospital. The diagnosis of NANB was based on the diagnostic standards for post-transfusion hepatitis of the Japanese Society of Gastroenterology 1985. In 587 patients with blood transfusions from 1978 to 1988, 80 patients (13.6%) were diagnosed as NANB. The proportions of blood components were, preserved whole blood 44.1%, concentrated red blood cells (CRBC)+ fresh frozen plasma 31.2%, and CRBC 12.8%. The proportions of blood components changed over the years, but since 1987 those of blood components in blood transfusion have been greatly decreased. No difference in the incidence of NANB was seen in patients with up to 10 units of blood transfused, but a high incidence was observed to patients who had received over 10 units. The number of patients treated by radical hysterectomy was five hundred and sixty-two (95.7%) out of a total of five hundred and eighty seven. The average blood loss in the operation was 1,392 ml.     

Intraductal ultrasonography for evaluating the patency of biliary metallic stents: correlation with cholangioscopic findings

Background: This is the first study to correlate intraductal ultrasonography (IDUS) with cholangioscopy in evaluating the patency of biliary metallic stents. Methods: The findings of IDUS (probe 2.0 mm in diameter and 20-MHz frequency) through a percutaneous transhepatic (n = 24) or transpapillary (n = 2) approach were retrospectively reviewed without other information. Criteria for IDUS are as follows: type 1, the inside of the stent is free; type 2, the inner edge is smooth; type 3, the inner edge is irregular; type 4, the inside of the stent is totally occupied; type 5, the solid echo is connected to the outside mass; type 2+D, a hypoechoic line is seen between the bile duct wall and the inside solid component and the inner edge of the bile duct wall is smooth; type 3+D, an irregular hypoechoic line is seen between the bile duct wall and the inside solid component. Results: In the control group (n = 11), IDUS showed type 1 (n = 9) or type 2 (n = 2). In the occluded group (n = 15), when IDUS showed type 3 or 5, the patients (n= 5) required additional stents (n = 3), microwave coagulation of the tumor (n= 1), or transient external drainage (n= 1). When IDUS showed type 4 (n = 5), after washing, the findings changed to type 2+D (n = 4). When IDUS after washing showed a smooth inner edge (type 2+D), the patients were treated without additional stents more frequently than the other groups (eight of nine vs. two of six), a significant distinction (p < 0.05). Conclusion: IDUS is useful in assessing the patency of metallic stents. When the inside of the stent is totally occupied, however, examination after washing is necessary. Received: 19 May 2000/Accepted: 28 June 2000     

Fc-dependent expression of CD137 on human NK cells: insights into "agonistic" effects of anti-CD137 monoclonal antibodies

CD137 (4-1BB) is a costimulatory mol-ecule that can be manipulated for the treatment of cancer and autoimmune disease. Although it is known that agonistic antibodies (mAbs) against CD137 enhance the rejection of murine tumors in a natural killer (NK) cell– and T cell–dependent fashion, the mechanism for NK dependence is poorly understood. In this study, we evaluated the ability of 2 different glycoforms of a chimerized antihuman CD137 mAb, an aglycosylated (GA) and a low fucose form (GG), to react with human NK cells. Both mAbs bound similarly to CD137 and partially blocked the interaction between CD137 and CD137 ligand. However, unlike GA mAb, immobilized GG mAb activated NK cells and enhanced CD137 expression. These effects were seemingly dependent on Fc interaction with putative Fc receptors on the NK-cell surface, as only the immobilized Fc-fragment of GG was required for CD137 expression. Furthermore, CD137 expression could be enhanced with antibodies directed against non-CD137 epitopes, and the expression levels directly correlated with patterns of Fc-glycosylation recognized to improve Fc interaction with Fc receptors. Our data suggest that CD137 can be enhanced on NK cells in an Fc-dependent fashion and that expression correlates with phenotypic and functional parameters of activation.