Cytoplasmic aggregation of TRAF2 and TRAF5 proteins in the Hodgkin-Reed-Sternberg cells

We previously reported that ligand-independent signaling by highly expressed CD30 in Hodgkin-Reed-Sternberg (H-RS) cells is responsible for constitutive activation of NF-kappa B. In the present study, we characterize the intracellular localization of tumor necrosis factor (TNF) receptor associated factor (TRAF) proteins in H-RS cells. Confocal immunofluorescence microscopy of cell lines derived from H-RS cells and HEK293 transformants highly expressing CD30 revealed aggregation of TRAF2 and TRAF5 in the cytoplasm as well as clustering near the cell membrane. In contrast, TRAF proteins were diffusely distributed in the cytoplasm in cell lines unrelated to Hodgkin's disease (HD) and control HEK293 cells. Furthermore, the same intracellular distribution of TRAF proteins was demonstrated in H-RS cells of lymph nodes of HD, but not in lymphoma cells in lymph nodes of non-Hodgkin's lymphoma. Dominant-negative TRAF2 and TRAF5 suppressed cytoplasmic aggregation along with constitutive NF-kappa B activation in H-RS cell lines. Confocal immunofluorescence microscopy also revealed co-localization of IKK alpha, NIK, and I kappa B alpha with aggregated TRAF proteins in H-RS cell lines. These results suggest involvement of TRAF protein aggregation in the signaling process of highly expressed CD30 and suggest they function as scaffolding proteins. Thus, cytoplasmic aggregation of TRAF proteins appears to reflect constitutive CD30 signaling which is characteristic of H-RS cells.     

Effects of nerve growth factor and glucocorticoid on cultured human pheochromocytoma cells

Primary cell cultures of two human pheochromocytomas (PC) that were associated with high serum levels of adrenaline and noradrenaline were developed to study the effects of nerve growth factor (NGF) and dexamethasone on the morphology and function of PC cells in vitro. By phase-contrast microscopy, cultured cells were small and hyperchromatic on the first day of culture; neurite-like processes that extended to other cells developed several days later and were maintained for more than 3 months. NGF (100ng/ml), dexamethasone (10^–5M), or NGF + dexamethasone were added to the culture media 2 weeks after the cultured cells had stabilized. Catecholamine concentrations in the medium were maintained at higher levels after addition of NGF, dexamethasone, or NGF + dexamethasone as compared to control cells. In the presence of NGF, extension of neurite-like processes was clearly accelerated, while high levels of dexamethasone inhibited growth of processes. These in vitro studies showed that the addition of NGF or the removal of dexamethasone induces differentiation of adrenal neurons present in pheochromocytomas, suggesting that adrenocortical steroid hormones influence the morphological control of adrenal medullary cells.     

Integration of retinal and motor signals of eye movements in striate cortex cells of the alert cat

Responses of saccade-depressed (SD) and saccade-excited (SE) cells in the striate cortex to eye movements of alert cats under presentation of a visual pattern were studied under reinforcement of the eye movements with rewards of water. These responses were compared to those on passive displacement of the visual pattern reproducing the movements of the retinal image occurring during eye movements while eye movements were suppressed by withdrawal of reinforcement. Passive displacement of the visual pattern produced in the SD cells depression closely resembled the depression occurring during eye movements under presentation of the visual pattern, in time course as well as in amplitude. Both the saccade depression and the depression due to passive movement of the visual pattern were nonselective to the direction of eye movements. Saccade excitation of the SE cells frequently contained two components occurring at 20 and 80 ms after the onsets of eye movements. Passive displacement of the visual pattern produced in the SE cells excitation comparable with the early component of the saccade excitation. These findings suggest that saccade depression in the SD cells and the early component of the saccade excitation in the SE cells are related to retinal reafference of eye movement. During presentation of visual patterns, saccade excitation in the SE cells was closely related to parameters of eye movements, such as direction, amplitude, duration, and velocity. The correlations were completely lost or strongly reduced in darkness. Lines of evidence were provided that the saccade excitation of the SE cells in darkness or the later component of the saccade excitation under presentation of a visual pattern represents efference copy signals of eye movement transferred to the striate cortex through the Clare-Bishop (CB) cortex. Excitation comparable with saccade excitation in darkness occurred in synchrony with activities of the oculomotor nuclei even after retrobulbar paralysis of eye movement, indicating that the excitation is related to efference copy signals rather than proprioceptive reafference of eye movement.(ABSTRACT TRUNCATED AT 400 WORDS)     

ABNORMAL INTRACRANIAL VASCULAR NETWORKS ("MOYAMOYA" DISEASE), POSSIBLY DUE TO OCCLUSION OF BILATERAL INTERNAL CAROTID ARTERIES — A CASE REPORT WITH HISTOMETRICAL ANALYSIS —

An autopsy case of abnormal Intracranial vascular networks at the base of the brain corresponding to so-called rete mirabile, associated with occlusion of bilateral internal carotid arteries was reported. This patient was a 62 year-old female who died about two months after sudden onset of subarachnoid hemorrhage. At autopsy, abnormal vascular networks termed as rete mirabile were observed to be collateral blood supplies among the cerebral regions with flow of the anterior, middle, and posterior cerebral arteries, caused by long-stading obstruction of bilateral internal carotid arteries at the syphon level. Morphometrical analysis was done by measuring the length of internal elastic membrane of the internal carotid arteries in cross section, and comparing it with those of controlled persons of the same sex and age without any intracranial disorders and hypertensive histories. The result that no significant difference was observed between the former and the latter values suggested that the unusual cerebro-vascular disorder of this case developed not on the base of congenital anomaly including hypoplasia of internal carotid arteries or arteriovenous malformation but as an acquired lesion established for a long time.     

The proliferating cell nuclear antigen (PCNA) index correlates with the grade of cytologic atypia in well-differentiated early adenocarcinomas of the large intestine

Well-differentiated colorectal adenocarcinomas are subclassified into carcinoma with high-grade atypia (CAH) and carcinoma with low-grade atypia (CAL) based on their cellular atypia. It is proposed that CAH and CAL are different in histologic prognostic factors and that the former should be regarded as carcinoma with high-grade malignancy and the latter as low-grade malignancy. In this study, the differences in cell-proliferative activity between CAH and CAL were examined using a monoclonal antibody to the proliferating cell nuclear antigen (PCNA). The PCNA index and mitotic index of 27 early colorectal carcinomas (9 CAL, 5 CAH, and 13 carcinomas with mixed low- and highgrade atypia) was evaluated in relation to their depth of invasion. In intra-mucosal lesions, both indices were higher in CAH (78%, 0.89%) than in CAL (68%, 0.47%; P <0.01). In lesions invading into the submucosa, the PCNA and mitotic indices were also higher in CAH (7596, 0.65%) than in CAL (35%, 0.19%; P <0.01). A significant correlation was observed between the PCNA index and the mitotic index in the mucosal lesions (P<0.05). These results indicate that CAH has a higher proliferative activity than CAL, and support the current authors' proposal that CAH is a high-grade malignancy and CAL a low-grade malignancy.     

Myocardial changes after infection with Coxsackie virus B3 in nude mice.

Athymic BALB/c-nu/nu (nu/nu) mice were inoculated i.p. with Coxsackie virus B3. The infected nu/nu mice were studied histopathologically, virologically and serologically in comparison with BALB/c-nu/+ (nu/+), BALB/c-+/+(+/+) and conventional ddY/S mice inoculated with the same virus. The virus titre in the hearts of nu/nu mice was roughly similar to that of nu/+ or +/+ and was higher than that of ddY/S. The neutralizing antibody titre in nu/nu mice was slightly lower than that of nu/+ or +/+ mice and somewhat lower than that of ddY/S mice. Histopathologically, there was a lack of mononuclear cells in myocarditis produced by Coxsackie virus B3 in athymic nu/nu mice. In contrast, myocarditis with mononuclear cell infiltrations were found in nu/+, +/+ and ddY/S mice. The lack of mononuclear cell reaction was a distinguishing difference in the myocardial changes of athymic nu/nu mice from those in nu/+, +/+ and ddY/S mice. The incidence in the myocardial lesions of nu/nu mice was about the same as those in nu/+, +/+ and ddY/S mice. However, the intensity of the myocardial changes of nu/nu mice was significantly less than that of other three groups. From the histopathological viewpoint, it is suggested that inflammatory response in the myocardium of mice infected with Coxsackie virus B3 is thymus-dependent.     

Sequence analysis of hepatitis B virus genomes from an infant with acute severe hepatitis and a hepatitis B e antigen-positive carrier mother

It is well known that fulminant hepatitis B can occur in infants born to hepatitis B e antigen (HBeAg)-negative hepatitis B virus (HBV) carrier mothers, whereas fulminant hepatitis and severe hepatitis are uncommon in infants born to HBeAg-positive mothers. We have encountered an infant with severe acute hepatitis B born to a HBeAg-positive mother. The aim of this study was to determine whether HBV variants contribute to the pathogenesis of fulminant hepatitis and severe hepatitis in an infant born to an HBeAg-positive mother. The nucleotide sequence of HBV genomes from the infant and his HBeAg-positive carrier mother was analyzed. All HBV isolated from the infant and his mother were subtype adr. The sequences of the cloned HBV genomes, each including a part of the X and precore/core regions, isolated from the infant were almost identical (homology of 99.1-99.9%) to those from his mother. There was no mutation in any of the 17 clones examined at nucleotides 1762 and 1764 in the core promoter, which is reported to be associated with fulminant hepatitis. A point mutation at nucleotide 1758 in the second AT-rich region of the basic core promoter was present in all clones. None of the clones had a point mutation at nucleotide 1896 of the precore region. In this study, no specific HBV variants contributing to the development of neonatal severe hepatitis were found. There is a possibility that host factors rather than viral factors play an important role in some cases of severe neonatal hepatitis B.     

Method for estimating the intensity of scattered radiation using a scatter generation model

An analytical formula for estimating the intensity of scattered radiation in an x-ray image under various exposure conditions has been developed. The formula was derived using measured data of scatter and primary intensity for various exposure conditions. To simplify the formula, a scatter generation model was constructed mathematically which assumes that the scattered fluence in a material depends on three processes: (1) scattering of the primary photons; (2) scattering of previously scattered photons; and (3) attenuation of the scattered photons. Using this model, the dependence of scatter-to-primary ratio on phantom thickness and the tube voltage was expressed by a simple equation. Parameters included in the model were determined from the analysis of measured data. Based on empirical data, it was assumed that the dependence of scatter-to-primary ratio on air gap and field size is not affected by variations of phantom thickness and tube voltage. The final formula, which does not include the term of phantom thickness, gives an estimate of the intensity of the scattered radiation from exposure conditions. The scatter intensity estimated using the formula was compared with measured data for various phantom thicknesses, tube voltages, air gaps, and field sizes; the results show that the intensity of scattered radiation can be estimated within about +/- 10% using predetermined parameters.     

Age-dependent changes in noradrenergic innervations of the frontal cortex in F344 rats

Noradrenergic innervations of the frontal cortex with advancing age (9, 13 and 25 months) in male F344 rats were quantified by immunohistochemistry for dopamine-beta-hydroxylase (DBH), which is a marker enzyme for noradrenergic axons. The density of DBH-positive axons, varicosities (swellings along an axon from which noradrenaline is released), and the number of varicosities per unit length of axon were measured in the frontal cortex. We found that the density of axons and varicosities significantly decreased at an earlier stage of aging (9-13 months), but not at a later stage (13-25 months). On the other hand, the number of varicosities per unit length of axon did not change with age. The result shows that the density of varicosities, which represent the synapses of noradrenergic neurons, decrease in the frontal cortex in the early aging process.     

Serum magnesium concentration is a significant predictor of mortality in maintenance hemodialysis patients

A few studies have reported a correlation between magnesium and co-morbidity and mortality in end-stage renal disease. We investigated the prognostic value of serum magnesium concentration for mortality in 515 patients on maintenance hemodialysis (60 +/- 12 years, 306 males and 209 females; 24% diabetics). The patients underwent follow-up for 51 +/- 17 (mean +/- SD) months, and the relationship between the baseline magnesium concentration (mean of four months) and outcomes was analyzed statistically. During the follow-up period, there were 103 all-cause deaths, including 63 non-cardiovascular deaths. Kaplan-Meier analysis revealed that mortality was significantly higher in the lower magnesium group (< 2.77 mg/dL, i.e. < 1.14 mmol/L, n = 261), compared to that in the higher magnesium group (> or = 2.77 mg/dL, n = 254) (p < 0.001). Multivariate Cox proportional hazard analysis demonstrated that serum magnesium was a significant predictor for mortality (HR [per 1 mg/dL increase], 0.485 [95% CI, 0.241-0.975], p = 0.0424), particularly for non-cardiovascular mortality (HR 0.318 [95% CI, 0.132 to 0.769], p = 0.0110), after adjustment for other confounders, such as age, gender, hemodialysis duration, and the presence of diabetes. In conclusion, it is demonstrated that lower serum magnesium level is a significant predictor for mortality in hemodialysis patients, particularly for non-cardiovascular mortality, although the mechanisms remain to be explored in future studies. Factors affecting serum magnesium concentrations should be investigated in terms of better survival, including dietary magnesium intake. Further extensive studies may be also needed for possible reconsideration of the current dialysate magnesium concentration (1.0 mEq/L, i.e. 0.50 mmol/L used in most countries), one of the strong contributors to the serum magnesium concentrations of dialysis patients.