Totally Implantable Ventricular Assist System Using a Vibrating Flow Pump

Abstract: A totally implantable ventricular assist system (VAS), including a drive system and a percutaneous electric energy transmission system, was developed and evaluated in acute animal experiments using adult goats. This newly designed VAS mainly consists of a vibrating tube, coils, magnets, and a jelly-fish valve as the outlet valve. For energy transmission, a new implantable transmitter with a plain weave structure was proposed as a noncon-tacting transform by using the spinal amorphous magnetic fibers. The fluid mechanical and hemodynamic properties and the efficiency of the energy transmission system were evaluated in acute animal experiments using healthy adult goats. This vibrating electromagnetic artificial heart (AH) could generate more than 10 L/min as output volume, with 10 Hz vibration using 20 volts as supplied voltage. The total efficiency of the percutaneous energy transmission system was 76%, and temperature increases were within the acceptable range, suggesting the usefulness of our newly developed implantable VAS.     

Speech disturbance following myelography with iohexol: a case report]

Iohexol (Omnipaque) is a non-ionic contrast media for neuroradiology, which causes the neurological complications on rare occasions. A 63-year-old, righthanded female suffered from dysphemia 12 hours after myelography with iohexol via lumbar puncture. The initial cerebral computed tomography scan revealed the generalized contrast media uptake into the cisterns, which was typical to the finding after intrathecal iohexol injection. Although the cerebral magnetic resonance (MR) imaging 7 days after attack also demonstrated no abnormal finding, the electrical encephalogram revealed the sporadic sharp wave activity. Her nonfluent speech deficit had recovered gradually, however, the neurogenic stuttering was still remained. Some literatures previously reported the cases with speech deficits as complications of metrizamide myelography, whereas, a case manifesting as speech disturbance following myelography with iohexol has been not reported. Metrizamide is also a non-ionic agent and had a lower incidence of speech disturbance, which is supposed to be associated with a focal superficial neurotoxic reaction of the cerebrum. Therefore, our unfortunate case suggests that iohexol could rarely cause speech disturbance such as metrizamide.     

Clinical pharmacology of combined oral uracil and ftorafur.

Phase I clinical trials of the combination of oral uracil with ftorafur (Ft) were conducted in patients with solid tumors over either a 5-day (345 mg/m2/day) or a 28-day (160 mg/m2/day) period. The uracil dose, which was four times the Ft dose (molar basis), was previously shown to be optimal at inhibiting the degradation of 5-fluorouracil (5-FU). Pharmacology was performed on the first dose of the first day of therapy. Ft was measured by HPLC, whereas uracil and 5-FU were measured using GC/MS. Plasma levels were highest for Ft, followed by uracil and 5-FU at all time points. Peak and trough levels after selected subsequent doses were also measured; these varied in the individual from day to day. Maximum plasma levels (Cpmax) for Ft, uracil, and 5-FU except in one patient were achieved at 0.6-2.1 hr, 0.6-4.1 hr, and 0.7-2.0 hr, respectively. Generally, lower doses yielded more rapid decay of 5-FU and uracil levels than did higher doses. No correlation was observed between myelotoxicities (granulocytopenia and leukopenia) and the Cpmax and AUC0-6hr of Ft (p > 0.2). However, after the highest uracil and Ft dose (approximately 300 mg/m2/Ft study dose), the Cpmax and AUC0-6hr values of 5-FU revealed significant differences (p < 0.05) in three patients each with and without myelotoxicity. These associations were similarly observed with uracil. Our findings thus indicate that measuring plasma uracil and more importantly, the 5-FU levels, may predict hematological toxicity and enable subsequent dose adjustments.     

PCB and PCQ Concentrations in Subcutaneous Tissue from Patients with PCB Poisoning (Yusho)

Polychlorinated biphenyl (PCB) and polychlorinated quaterphenyl (PCQ) concentrations in the blood and subcutaneous fat tissue from 11 patients with PCB poisoning (Yusho) and 10 controls were analyzed by electron captured gaschromatography. The mean concentration levels of blood PCB and PCQ and the CB% ratio were elevated in patients with Yusho. The PCB pattern was the A type in 5 cases and the B type in 6 others. The mean concentration level of PCB in subcutaneous fat tissue was 1579.45 ppb in the Yusho group, 3.9 times higher than that in the control group. The mean concentration level of PCQ was 206.65 ppb, 119 times higher than that in the control group. The mean value of CB% was 3.22 in the Yusho group and 0.66 in the control group. These results show that PCB and PCQ accumulate in the subcutaneous fat tissue of patients with PCB poisoning (Yusho), as late as 17 years after diagnosis of the disease. The PCB and PCQ concentration levels in the subcutaneous fat tissue appear to be useful in diagnosis and evaluation of prognosis in this disease. Investigations of the elimination of PCB and PCQ in subcutaneous tissues should be done.     

Moderately T2-weighted images obtained with the single-shot fast spin-echo technique: differentiating between malignant and benign urinary obstructions.

The purpose of this study was to determine whether a distinction could be made between benign and malignant urinary obstructions in moderately T(2)-weighted images obtained with the single-shot fast spin-echo technique. Forty-four lesions in 39 patients with urinary obstruction were evaluated with the single-shot fast spin-echo (SSFSE) technique with an effective TE of 90-100 ms and without fat saturation. Benign and malignant lesions were compared for the presence of ureteral wall thickening and a signal intensity relative to the proximal ureteral wall. Statistically significant differences were found between benign and malignant lesions in both morphologic change (P<0.0001) and signal intensity of the lesions at the obstruction position (P<0.0001). The combination of wall thickening and increased signal intensity as a predictor of malignant disease yielded a sensitivity of 88% and a specificity of 100%. Neither increased signal intensity nor wall thickening as a predictor of benign disease yielded a sensitivity of 89% and a specificity of 88%. The moderately T(2)-weighted SSFSE technique without fat saturation can accurately distinguish between benign and malignant urinary obstructions.     

Adrenal venous sampling analysis of primary aldosteronism: value of ACTH stimulation in the differentiation of adenoma and hyperplasia

Adrenal venous blood samples drawn before and after stimulation with adrenocorticotropic hormone (ACTH) were analysed in 32 consecutive patients with primary aldosteronism. Twenty-six patients had aldosterone-producing adenomas and six patients had bilateral hyperplasia.The ratio of higher to lower levels of aldosterone in the right and left adrenals (aldosterone ratio), aldosterone to cortisol ratio (A/C ratio), and the ratio of higher to lower levels of A/C ratio in the right and left adrenals (ratio of A/C ratios) were calculated. We used both aldosterone ratio and ratio of A/C ratios as a means of diagnosis, a ratio of 3.0 or more for unilateral adenoma, and less than 3.0 for bilateral hyperplasia. With ACTH stimulation, correct characterization of lesions increased from 91% (29 of 32) to 97% (31 of 32) by aldosterone ratio and from 84% (27 of 32) to 97% (30 of 31) by ratio of A/C ratios. Correct diagnosis of bilateral hyperplasia increased markedly from 67% (4 of 6) to 100% and 50% (3 of 6) to 83% (5 of 6) with use of each criterion.In patients with adenoma, aldosterone ratio rose in 54% (14 of 26) from the pre-stimulation levels. Before stimulation, it ranged from 1.5 to 115.9 (mean 34.8), and afterwards, from 2.1 to 1097.9 (mean 95.5). In contrast, in all patients with bilateral hyperplasia aldosterone ratio fell to less than 3.0 following stimulation with ACTH. With ACTH stimulation, aldosterone ratio increased in patients with adenoma and decreased in patients with hyperplasia.Measurement of A/C ratio is used to ensure correct access to the adrenal veins, but it was useful in only one case and aldosterone ration was a more reliable diagnostic parameter than ratio of A/C ratios in both pre-and post-ACTH stimulations.Assay of aldosterone levels and calculation of aldosterone ratios before and after ACTH stimulation were valuable in locating small adenomas in the right and left adrenal and especially in differentiating bilateral hyperplasia from adenoma.     

Precision in the first stage of the gastric carcinoma mass survey

A new method of estimating false-negative rate (FNR) in gastric carcinoma mass surveys is reported. It is called the “ADC method”, since estimation of FNR is based on “Accidentally Detected Carcinoma”. ADC is a carcinoma detected by chance upon close examination because of abnormalities falsely pointed out in the first stage of the mass survey (mass screening) in a region other than the one in which carcinoma is located. This method was tested in the gastric carcinoma mass survey program conducted by the Hokkaido Anti-cancer Association. Overall FNR was estimated at 28.3%. The FNRs estimated by the ADC method appear more reasonable and reliable indicators of precision of the mass survey program. The ADC method is discussed in comparison with the previously used “follow-up study” and several advantages of this new method are presented.     

Development of the Accelerated Phase during Ascorbic Acid Therapy in Chediak-Higashi Syndrome and Efficacy of Colchicine on its Management

S ummary. Clinical studies were done on a patient with Chediak-Higashi syndrome (CHS) with special emphasis on the accelerated phase. In order to obtain further information on the accelerated phase, haematopoiesis was studied by bone marrow culture techniques. The patient was placed on ascorbic acid therapy but she entered the accelerated phase, although the therapy improved in vitro neutrophil function to some extent. Administration of microtubulytic drugs such as vincristine, vinblastine and colchicine was effective in the management of the accelerated phase. Numbers of macrophage-granulocytic (CFU-C) and erythroid (CFU-E) progenitor cells were markedly decreased or absent during the accelerated phase, being another indicator of the accelerated phase.     

The Effect of Mature Adipocyte-Derived Dedifferentiated Fat (DFAT) Cells on a Dorsal Skin Flap Model

Background: Dedifferentiated fat (DFAT) cells, isolated from mature adipose cell, have high proliferative potential and pluripotency. We report on the expansion of flap survival areas on the back of rats administrating DFAT cells. Materials and Methods: Intraperitoneal adipose tissue was collected from a male Sprague-Dawley (SD) rat. The mature fat cells were cultured on the ceiling surface of culture flask to isolate DFAT cells. On day 7 of the culture, the flask was inverted to allow normal adherent culture. A dorsal caudal-based random pattern flap measuring 2 × 9 cm was raised on each SD rat. We prepared a control group (n = 10) and a flap base injection group in which DFAT cells were injected 2 cm from the flap base (n = 10) and a flap center DFAT injection group (n = 10). In which DFAT cells at 1 × 106 cells/0.1 ml were injected beneath the skin muscle layers of the flap. The flap survival areas were assessed on day 14 after surgery. Results: The mean flap survival rates of the control group, flap center injection group and flap base injection group were 53.6 ± 6.1%, 50.6 ± 6.4% and 65.8 ± 2.4%, respectively. The flap survival areas significantly expanded in the flap base injection group (p < .05). In H-E staining beneath the skin muscle layer connective tissue thickened in the flap base injection group. In the India ink staining, abundant neovascularization was observed inside the thickened parts. Conclusion: The injection of DFAT cells into the flap base promoted the expansion of survival areas.