Morphological inspection of 80 consecutive Gyro pumps after cardiopulmonary bypass

 We have been using the Gyro centrifugal pump C1E3 for cardiopulmonary bypass in anticipation of high efficiency, low hemolysis, and antithrombogenicity of this pump. However, the clinical evaluation of this pump remains to be clarified, because it has been a short time since the pump appeared in clinical situations. The aim of the present study is to inspect and analyze the Gyro pumps morphologically after clinical use. We examined 80 consecutive pumps after cardiopulmonary bypass for 186 ± 67 min with a mean flow rate of 2.52 ± 0.22 l/min/m² at a mean rotational speed of 2485 ± 81.1 rpm. Although no abnormal findings were present in 79 pumps, one pump was found to contain effusion at the connection between the impeller body and the shaft. The extudate was supposed to be blood, based upon the results of X-ray spectrometer analysis. The cause was determined to be the upward deviation of the shaft off the impeller body. Scanning electron microscopy showed scratches on a part of the bottom housing and a smooth surface of both the male and female pivots of the pump. Surface profile measurement revealed that the deformity of the female pivots was 0.14 mm (top) and 0.05 mm (bottom). These observations suggest that the floating force and vibration by the rotating impeller acted on the joint zone between the alumina ceramic shaft and the polycarbonate impeller body, resulting in dissection of the adhesive agent from the polycarbonate. Although this abnormality may be rare, the structural design still may need to be improved. Received: November 9, 2001 / Accepted: February 4, 2002     

Purification of fully activated Clostridium botulinum serotype B toxin for treatment of patients with dystonia

Clostridium botulinum serotype B toxins 12S and 16S were separated by using a beta-lactose gel column at pH 6.0; toxin 12S passed through the column, whereas toxin 16S bound to the column and eluted with lactose. The fully activated neurotoxin was obtained by applying the trypsin-treated 16S toxin on the same column at pH 8.0; the neurotoxin passed through the column, whereas remaining nontoxic components bound to the column. The toxicity of this purified fully activated neurotoxin was retained for a long period by addition of albumin in the preparation.     

Galactosylated chitosan as a synthetic extracellular matrix for hepatocytes attachment

Galactose moiety as the hepatocyte anchorage was covalently coupled with chitosan for the development of synthetic extracellular matrix. Hepatocytes adhesion to galactosylated chitosan (GC)-coated polystyrene (PS) dish became as high as 94.7% after 2 h incubation whereas the hepatocytes adhesion to chitosan-coated PS dish was 69.1%, indication of galactose-specific recognition between GC molecules and asialoglycoprotein receptors of hepatocytes. The DNA synthesis of the hepatocytes adhered to GC-coated dish was increased in the presence of epidermal growth factor (EGF) at low concentration of GC (0.05 microg/ml) whereas the DNA synthesis of the hepatocytes adhered to GC-coated dish was decreased in the presence of EGF at high concentration of GC (5 microg/ml). The spreading shapes of the hepatocytes adhered to the surface in the presence of EGF at low concentration of GC (0.05 microg/ml) were enhanced than in the absence of EGF. The hepatocytes adhered to the surface at high concentration of GC (5 microg/ml) showed round shapes and exhibited many spheroid formation after 24 h in the presence of EGF.     

Melanoma cell adhesion molecule (MCAM/CD146) is expressed on human luteinizing granulosa cells: enhancement of its expression by hCG,interleukin-1 and tumour necrosis factor-alpha

Melanoma cell adhesion molecule (MCAM) was originally reported to be involved in the invasion and progression of melanoma. It was also shown to be responsible for the attachment of cells to endothelial cells. In this study, we demonstrated by immunohistochemistry that immunoreactive MCAM was not expressed on granulosa cells in the pre-ovulatory follicle, but it was clearly detected in large luteal cells in corpora lutea from the mid-luteal phase of the menstrual cycle. Northern blotting analysis confirmed the expression of MCAM mRNA in corpus luteum. MCAM was weakly detected by immunocytochemical staining in human luteinizing granulosa cells isolated from patients undergoing IVF treatment. Its expression was found to be increased during time in culture of these cells. Flow cytometry and Northern blot analysis revealed that MCAM expression on luteinizing granulosa cells was enhanced when the cells were cultured for 5 days in the presence of hCG (1 IU/ml) or cytokines such as interleukin-1alpha (10 ng/ml) and tumour necrosis factor-alpha (10 ng/ml). No significant difference of MCAM expression was observed between the cultures under normoxic (20% oxygen) and hypoxic (1% oxygen) conditions. These results indicate that luteinizing granulosa cells express MCAM and that MCAM expression is regulated by LH/hCG and cytokines during luteinization. Since MCAM has been reported to mediate cellular interaction with endothelial cells, this molecule may play a role in neovascularization during corpus luteum formation in the human ovary.     

Generation of velogenic Newcastle disease viruses from a nonpathogenic waterfowl isolate by passaging in chickens

A benign Newcastle disease virus (NDV) recently became highly virulent during replication in domestic chickens. It is still unclear whether NDVs circulating among wild waterfowl also have the potential to become highly pathogenic (velogenic) in chickens. To demonstrate experimentally the generation of velogenic NDV from a nonpathogenic waterfowl isolate, we passaged an avirulent goose isolate in chickens. After nine consecutive passages by air-sac inoculation, followed by five passages in chick brain, the virus became highly virulent in chickens, producing a 100% mortality rate, and demonstrating typical velogenic properties in pathogenicity tests. Sequence analysis at the fusion protein cleavage site showed that the original isolate contained the typical avirulent type sequence, E-R-Q-E-R/L, which progressed incrementally to a typical virulent type, K-R-Q-K-R/F, during repeated passage in chickens. These results demonstrate that avirulent viruses, maintained in wild waterfowl in nature and bearing the consensus avirulent type sequence, have the potential to become velogenic after transmission to and circulation in chicken populations. The results also suggest that chickens provide a mechanism for the selection of virulent viruses from an avirulent background.     

Heavy-ion-induced mutations in the gpt delta transgenic mouse: comparison of mutation spectra induced by heavy-ion,X-ray,and gamma-ray radiation

Heavy-ion radiation accounts for the major component of absorbed cosmic radiation and is thus regarded as a significant risk during long-term manned space missions. To evaluate the genetic damage induced by heavy particle radiation, gpt delta transgenic mice were exposed to carbon particle irradiation and the induced mutations were compared with those induced by reference radiations, i.e., X-rays and gamma-rays. In the transgenic mouse model, deletions and point mutations were individually identified as Spi(-) and gpt mutations, respectively. Two days after 10 Gy of whole-body irradiation, the mutant frequencies (MFs) of Spi(-) and gpt were determined. Carbon particle irradiation significantly increased Spi(-) MF in the liver, spleen, and kidney but not in the testis, suggesting an organ-specific induction of mutations by heavy-ion irradiation. In the liver, the potency of inducing Spi(-) mutation was highest for carbon particles (3.3-fold increase) followed by X-rays (2.1-fold increase) and gamma-rays (1.3-fold increase), while the potency of inducing gpt mutations was highest for gamma-rays (3.3-fold increase) followed by X-rays (2.1-fold increase) and carbon particles (1.6-fold increase). DNA sequence analysis revealed that carbon particles induced deletions that were mainly more than 1,000 base pairs in size, whereas gamma-rays induced deletions of less than 100 base pairs and base substitutions. X-rays induced various-sized deletions and base substitutions. These results suggest that heavy-ion beam irradiation is effective at inducing deletions via DNA double-strand breaks but less effective than X-ray and gamma-ray irradiation at producing oxidative DNA damage by free radicals.     

Neural fibrolipoma of the superficial peroneal nerve in the ankle: a case report with immunohistochemical analysis

This report presents a case of neural fibrolipoma arising from the superficial peroneal nerve in the ankle. A 28-year-old woman was referred with a soft tissue mass in the anterior aspect of the right ankle, which had been gradually enlarging for the past 10 years. Magnetic resonance imaging showed a mass lesion, measuring approximately 8 x 3 x 2 cm, with high to partially low signal intensity on both T1- and T2-weighted images. A band of low signal intensity within the lesion, which is indicative of coexistence with the tumor and the superficial peroneal nerve, could be detected on both T1- and T2-weighted images. The patient underwent an excisional biopsy. The specimen microscopically consisted of nerve bundles and fibro-fatty proliferation with abundant collagen fibers. Immunoreactivity for CD34 antigen antibody was detected in fibrous spindle cells. This is the first report to present an immunohistochemical profile of neural fibrolipoma. Neural fibrolipoma should be considered as a differential diagnosis when a lipomatous lesion is encountered in the foot or ankle as well as in the upper extremities.     

Involution of lymph node histiocytes in AIDS

Lymph nodes of human immunodeficiency virus (HIV)-infected patients were studied histologically and immunohistochemically to elucidate the pattern of involution of various histiocytes in AIDS. Specimens consisted of one node with hyperplasia, five with atrophy, and three with severe atrophy. Antibodies such as L25, ID1, My4, 12, anti-Leu 3a, KiM4, OKT6 and anti-S100 protein were used for identification of the histocytes. Another antibody, VAK5, was used to demonstrate HIV antigen. T-zone histiocytes were mildly decreased in the hyperplastic node, but considerably decreased in the atrophic nodes. My4+ sinus histiocytes were unchanged in number and enlarged in the hyperplastic node, but not decreased in the atrophic nodes. Follicular dendritic cells (FDCs), defined by KiM4, were mostly depleted in the atrophic nodes. The T4 antigen was detected in some of the sinus histiocytes of the atrophic nodes. T6-positive cells were not found in any of the nodes. HIV antigen was detected only in FDCs. It is therefore suggested that various histiocytes respond differently to HIV, and that T-zone histiocytes and sinus histiocytes persist up to the late stage of AIDS.     

Momentary changes in the cardiovascular autonomic system during mental loading in patients with panic disorder: a new physiological index "rho(max)"

BACKGROUND: Although panic disorder (PD) is suggestive of autonomic nervous system dysfunction, especially in the cardiovascular autonomic system (CAS), the results in many previous studies are still controversial. Using a new physiological index which could well reflect emotional reaction to visual stimuli (Yoshizawa, M., Sugita, N., Tanaka, A., Abe, K., Yambe, T., Nitta, S., 2001. Quantiatative Physioligical Evaluation of Three Dimensional Images. The Seventh International Conference on Virtual Systems and Multumedia, 25-27.), we studied momentary changes in the CAS in patients with PD during audiovisual stimulation (AS) as mental loading. METHODS: During AS, exposed to a video of imaginary experiences such as driving a motor vehicle or diving into the sea, blood pressure (BP) and heart rate (HR) were measured in 12 remitted patients with PD and 19 age- and sex-matched normal controls (NC). We used the maximum cross-correlation coefficient (rho(max)) from the BP to the HR, whose frequency components were limited to around 0.1 Hz. RESULTS: The rho(max) was an available index which could detect the momentary changes in the CAS during AS in both groups. The two-way ANOVA disclosed significant group and time effects on the rho(max). The momentary response to emotional stimuli in the PD patients was slower than that in the NC subjects. LIMITATIONS: Antidepressants have a potential impact on the autonomic variables in this study. CONCLUSIONS: These findings suggest that there may be a dysfunction of the CAS in remitted PD patients and that the dysfunction may be one of the trait markers of PD. To confirm these findings, however, further studies with a large sample size are required.