The effects of oligomers content and surface morphology on foreign-body tumorigenesis with polyetherurethanes: two years subcutaneous implantation study in rats

Three polyurethane materials were prepared by removing and adding the leachable oligomers from and to the same polyetherurethane (PEU). The three PEU materials were dissolved in tetrahydrofuran (THF) and dimethyformamide (DMF) and the solutions were cast on a glass plate to make films of smooth and foamed surfaces, respectively. These six materials and polydimethylsioxane (silicone) were implanted into subcutaneous pocket of rats for 2 years to evaluate the long-term effects around the implant. Among the smooth surface implants, PEU materials induced a higher incidence of tissue responses, including tumor formation than silicone. However, no relationship between the oligomer content and the tissue responses was found. Changing surface morphology from a smooth to a foamed one prolonged the latent period of tumor development and decreased the total tumor incidence.     

Non-invasive continuous hemodynamic measurement during operation for a child with coarctation of aorta

For non-invasive hemodynamic monitoring, DYNEMO 3000 (SOMETEC Inc) has a 10 mHz ultrasonic echo scan and a 5 mHz Doppler velocimeter connected to an echo-oesophageal probe allowing continuous measurement of the aortic diameter and of the blood flow velocity in the descending aorta. This device thus can only measure the aortic blood flow, but also calculate the stroke volume and the systemic vascular resistance. Moreover, the systolic time intervals and the length of the pre-ejection period can be measured with the oscillometric tensiometer and the electrocardiography. This paper describes a case in which this device was used for a child with coarctation of the aorta. The hemodynamic changes were measured continuously during coarctectomy. During the temporary bypass, the aortic blood flow and the stroke volume decreased, but on the other hand, the total vascular resistance increased at the same time. After the bypass, these parameters returned to the values before the bypass. We think that this device is useful as a non-invasive monitor to observe the hemodynamic changes continuously during operation for a child with congenital heart disease.     

Utility of endoscopic ultrasonography in assessing the indications for endoscopic surgery of submucosal esophageal tumors

BACKGROUND: The submucosal tumor (SMT) of the esophagus presents good indications for minimal invasive surgery, such as endoscopic or thoracoscopic resection. However, it is essential that the layer of origin be ascertained. The SMT can be detected as hypoechoic lesions in the wall of the esophagus, and the intramural location can be estimated in terms of destruction or deviation of the ultrasonic layer structure of the esophagus. METHODS: To test the efficacy of this approach, a series of patients were examined by an endoscopic ultrasonography (EUS). RESULTS: In one patient, the lesion was diagnosed as located in the muscularis mucosa, and endoscopic resection was performed. In another four patients, the lesions appeared to be in the proper muscle layer, and enucleation was carried out under thoracoscopy or open surgery. Histologically, all of the lesions were leiomyomas, and the EUS diagnosis was correct in all of the patients. CONCLUSIONS: Thus, the intramural condition of SMTs can be estimated and indications for endoscopic or thoracoscopic resection assessed by this approach.     

Surgical treatment of a case of early infantile epileptic encephalopathy with suppression-bursts associated with focal cortical dysplasia

We report a surgically treated case of early infantile epileptic encephalopathy (EIEE) with suppression-bursts associated with focal cortical dysplasia. Tonic-clonic seizures followed by a series of spasms occurred about a hundred times a day at a few days of age. Interictal electroencephalogram (EEG) revealed a suppression-burst pattern that was predominant in the left hemisphere. Magnetic resonance imaging (MRI) suggested focal cortical dysplasia in the left prefrontal area. Combination therapies with antiepileptic treatments showed only partial efficacy. The patient underwent lesionectomy at age 4 months, after which he gradually showed psychomotor development and a decrease of spasms to 0-2 series daily. In cases of EIEE with focal cortical dysplasia, surgical treatment may have beneficial effects on both psychomotor development and seizure control.     

Endothelin antagonist treatment for successful liver transplantation from non-heart-beating donors

BACKGROUND: With the shortage of cadaveric donors, non-heart-beating donors (NHBDs) are a potential source of liver allografts. However, warm ischemic injury in NHBDs seriously affects the viability of graft liver. Endothelin (ET)-1 has been reported to be involved in the hepatic microcirculatory disturbances after ischemia-reperfusion. METHODS: In a porcine orthotopic liver transplantation model, changes in the serum and liver tissue ET-1 concentration were measured and the effects of an ET receptor antagonist, TAK-044, were evaluated. After cardiac arrest of the donors, liver allografts were subjected to 90 min of warm ischemia, flushed, and preserved for 4 hr at 4 degrees C. The pigs were divided into two groups: a control group (no drug treatment) and a drug-treated group, in which donors and recipients were treated with TAK-044 (10 mg/kg body, drip intravenous injection). Both groups had six donor/recipient pairs. RESULTS: -The ET-1 concentration in the hepatic venous blood increased after reperfusion of the graft in the control group recipients. ET-1 in the graft liver significantly increased during the cold preservation period. TAK-044 treatment significantly increased recipient 7-day survival rate. After reperfusion of the graft, the concentrations of serum liver enzymes and arterial lactate in the drug-treated group were significantly lower than in the control group. The postoperative increase in portal venous pressure was significantly reduced in the drug-treated group. Measurements of liver enzymes in the washed-out preservation fluid at the time of graft rinsing indicated that TAK-044 treatment of the donors significantly suppressed liver enzyme release during ischemia. CONCLUSIONS: These findings indicate TAK-044 treatment has protective effects on postoperative function of hepatic allografts procured from NHBDs.     

Total Esophagectomy versus Proximal Esophagectomy for Esophageal Cancer at the Cervicothoracic Junction

To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy (total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients.