Usefulness of Flexible Colonoscopic Microwave Coagulation Therapy for a Colorectal Anastomotic Stricture

PURPOSE: Several methods of treatment for benign anastomotic strictures after anterior resection have been described. We describe a simple, safe, effective, and inexpensive method for treating benign colorectal anastomotic stricture by means of microwave coagulation under flexible colonoscopic visualization. METHODS: Eighteen patients with rectal or rectosigmoidal cancer underwent low anterior resection or anterior resection without colonic pouch and colorectal anastomosis by a double-stapling technique with PCEEA. Two of 18 patients (11.1 percent) developed an anastomotic stenosis. A microwave electrode was passed through the biopsy channel of the flexible colonoscope. Under flexible colonoscopic visualization, microwave irradiation was performed at four points (3, 6, 9, and 12 oclock) in the stricture site because of granulation scar to obtain an adequately coagulated area. No bougies were performed thereafter. RESULTS: The anastomotic strictures could be dilated adequately, the patients could defecate satisfactorily, and their abdominal distentions and bowel symptoms were resolved. No complications occurred. No occurrence of restricture has been observed. CONCLUSION: Flexible endoscopic, microwave coagulation therapy is a useful, simple, effective, and safe method for the treatment of benign colorectal anastomotic strictures.     

MR-guided percutaneous cryotherapy of malignant liver tumor under horizontal-magnetic open system: initial experience

BACKGROUND/PURPOSE: We describe the feasibility and accuracy of magnetic resonance (MR)-guided cryotherapy for malignant liver tumor, using a horizontal-magnetic open system. METHODS: Using an MR-compatible cryotherapy system and horizontal-magnetic open-configuration MR scanner, we performed percutaneous cryotherapy for four malignant liver tumors. RESULTS: All procedures were carried out safely and accurately without any serious complication. Residual tumor was observed in one patient with metastatic liver tumor located directly under the diaphragm. CONCLUSIONS: MR-guided cryotherapy appears to be ideal and desirable as a minimally invasive therapy for liver tumor.     

Hippocampal lesion delays the acquisition of egocentric spatial memory in chicks

Effects of bilateral chemical lesion of the hippocampus was examined in 1- to 2-week-old domestic chicks. Chicks were trained and tested in an egocentric spatial task, in which subject chicks should memorize location of a rewarding object in reference to the subject's viewpoint. Two beads were simultaneously presented on a wall, and chicks pecked at one of them based on relative location (left-right or above-below) to gain a reward. Comparison of training curves revealed that the lesion significantly delayed, but did not impair, the acquisition. Recall of the spatial cue, as well as conditioning with color cues, was not impaired. Hippocampus could thus be involved in memory formation of spatial relationships between nearby objects.     

Relationship between the local stiffness of the outer hair cell along the cell axis and its ultrastructure observed by atomic force microscopy

As electromotility may arise from a conformational change of the molecules' 'protein motors', which might be distributed along the outer hair cell (OHC) lateral wall, the force generated by the OHC electromotility would be related not only to the conformational change of the protein motors but also to the mechanical properties of the lateral wall. Therefore, a detailed understanding of the mechanical properties of the OHC lateral wall is important. In our previous reports, to understand the difference in the stiffness along the cell axis, the local deformation of the OHC in response to hypotonic stimulation was analyzed by measuring the displacement of microspheres attached randomly to the cell lateral wall, and the distribution of Young's modulus along the cell axis was obtained using the contact mode of an atomic force microscope (AFM). These investigations revealed that the stiffness of the cell in the apical region was greater than that in other regions where the stiffness is constant. In this study, the ultrastructure of the OHC lateral wall was investigated with the oscillation imaging mode of the AFM (Tapping Mode), and the relationship between the stiffness along the cell axis and the ultrastructure that was observed by the AFM imaging was analyzed. From the analysis, it was concluded that the circumferential filaments observed in the tapping mode AFM are actins which are part of the cortical lattice, and that the difference between the intervals of the circumferential filaments in the apical region and those in other regions is one factor that causes the high stiffness in the apical region.     

Treatment parameters for selective occlusion of experimental corneal neovascularization by photodynamic therapy using a water soluble photosensitizer, ATX-S10(Na)

Time dependent change of an accumulation of an amphiphilic photosensitizer, ATX-S10(Na) on rabbit corneal neovascularization (CoNV) was evaluated by angiography using ATX-S10(Na) as a fluorescent dye on three rabbits. The angiography showed that the dye accumulated on CoNV 3-5 hr after dye injection when the dye in the iris was minimum. The results suggested 3-5 hr after might be the optimal time to start photodynamic therapy (PDT) to occlude CoNV selectively without damage to the surrounding normal tissue such as the iris. Then the optimal treatment parameters in PDT using ATX-S10(Na) for selective occlusion of the CoNV were investigated on rabbit eyes. PDT was performed with two different time intervals between dye injection and laser irradiation of a diode laser (670 nm), different laser doses and three different dye doses on 21 animals. PDT performed immediately after dye injection selectively occluded CoNV with laser irradiations from 30.6 to 38.2 J cm(-2)and a 2 mg kg(-1)dose of ATX-S10(Na), as well as with 15.3 J cm(-2)and a 6 mg kg(-1)dose. PDT performed 4 hr after dye injection with 107.0-152.8 J cm(-2)and a 6 mg kg(-1)dose, as well as with 38.2-53.5 J cm(-2)and a 12 mg kg(-1)dose was also effective. Although PDT performed either immediately or 4 hr after ATX-S10(Na) injection selectively occluded CoNV, the width of the optimal range of radiant exposures seemed wider in PDT performed 4 hr after dye injection. It is supposed that this result is associated with the difference of dye accumulation between in CoNV and in normal tissue as shown by the present angiographical findings.     

Normalization of retinal vascular permeability in experimental diabetes with genistein

PURPOSE: To study the effects of genistein, a tyrosine kinase inhibitor, on retinal vascular permeability in an experimental diabetic rat model. METHODS: Seventy-two rats were equally divided into four groups: (1) nondiabetic control group, (2) diabetic control group, (3) diabetic rats receiving 150 mg genistein/kg food, and (4) diabetic rats receiving 300 mg genistein/kg food. Diabetes was induced by streptozotocin injection in the three diabetic groups. Rats were fed diets with or without genistein and followed for 6 months. Retinal vascular permeability was assessed by measuring radiolabeled sucrose leakage into the retina and by Western blot analysis for total retinal albumin. Retinal phosphotyrosine levels and proliferating cell nuclear antigen (PCNA) were also evaluated by Western blot analysis. RESULTS: Diabetic control rats had markedly increased retinal vascular leakage of radiolabeled sucrose compared with nondiabetic control rats. Diabetic rats receiving oral genistein had significantly less retinal vascular leakage of radiolabeled sucrose than diabetic control rats in a dose-response fashion. Diabetic control rats had increased levels of phosphotyrosine, retinal albumin, and PCNA by Western blot analysis compared with nondiabetic control rats. Rats receiving 300 mg of genistein had decreased retinal albumin by Western blot analysis. Western blot analysis demonstrated a dose-response decrease in retinal phosphotyrosine levels and PCNA in genistein-treated diabetic rats compared with diabetic control rats. CONCLUSIONS: Long-term oral administration of genistein significantly inhibits retinal vascular leakage in experimentally induced diabetic rats. Tyrosine kinase inhibition may be a useful pharmacological approach for the treatment of diabetic-induced retinal vascular leakage.     

Tolerance induction in immunologically intact adult rats with allogeneic spleen cell transfusion from dexamethasone-treated rats

Recentfindingssuggestthatneonatalsarenotspe-ciallypronetoimmunologicaltoleranceinduction,butequallycompetentintheinductionofaprimaryim-muneresponse,challengingthe"selfandnon-self"discriminationmodelinimmunerecognitionthathasbeenconsideredoverfortyyearsthetheoremofim-munesystem[1,2].Thus,themysterybehindthehightoleranceinductivityinneonatalsmaynotbeduetothedifferentquality,butalowquantityofimmunolog-icallycompetentcellsascomparedwiththoseinadults.Asaresult,theconsequenceofanimmunerecognition,be…     

Treatment for brain metastasis from lung cancer in the era of radiosurgery

OBJECTIVE: The treatment for brain metastasis has undergone remarkable changes since the development of radiosurgery. We investigated the results of treatment for brain metastasis from lung cancer since the initiation of gamma knife radiosurgery (GKRS) and we discuss the usefulness of GKRS combined with other treatments in cases with recurrence. METHODS: We treated 142 patients with brain metastasis from lung cancer. Sixteen patients were treated surgically, 11 patients were treated with whole brain radiation therapy (WBRT), and 115 patients were treated with GKRS. Our treatment plan is to use GKRS in cases with less than 5 lesions and lesions less than 3 cm in mean diameter. We use WBRT in cases with 5 or more lesions, and surgery in cases with lesions 3 cm or larger. If new lesions or tumor regrowth appeared after the initial treatment, we retreated them with one of the methods mentioned above. RESULTS: Twice or three-time treatments were performed in 30 patients. Median survival including all cases was 10 months and the number of deaths due to local treatment failure was only 5 (6.5%) out of the total 77 deaths which occurred. CONCLUSION: We were able to carry out less invasive treatment for brain metastasis from lung cancer by utilizing GKRS. Though we have to consider the indications for other treatments, we can say that radiosurgery is usually the treatment of first choice for brain metastasis from lung cancer. When new lesions appear in cases where a particular initial treatment was used, it is possible to maintain or improve the quality of life by retreatment, using a combination of GKRS, surgery or WBRT, to prolong the patient's life.