Synergistic Effects of Highly Unsaturated Fatty Acid-containing Phosphatidyl-ethanolamine on Differentiation of Human Leukemia HL-60 Cells by Dibutyryl Cyclic Adenosine Monophosphate

Highly unsaturated fatty acid-containing phospholipid (HUFA-PL) has many nutritional and medical applications. We investigated the effect of HUFA-PL on differentiation of human leukemia HL-60 cells induced by dibutyryl cyclic adenosine monophosphate (dbcAMP). HUFA-containing phosphatidylethanolamine (HUFA-PE), such as salmon testis PE, significantly enhanced dbcAMP -induced cell differentiation. A combined treatment of 200 μM dbcAMP with 50 μ M HUFA-PE increased the nitroblue tetrazolium (NBT)-reducing activity, which is an indicator of differentiation, to a level comparable to that in the case of 500 μ M dbcAMP treatment. In contrast, HUFA-lyso PE (a monoacyl form) did not exert an enhancing effect on dbcAMP-induced differentiation. The enhancing effect of HUFA-PE was suppressed by a protein kinase C inhibitor, staurosporine, while a protein kinase A inhibitor, H-8, did not suppress the enhancing effect. These findings suggest that HUFA-PE might enhance dbcAMP-induced differentiation through modulation of the protein kinase C signaling pathway in HL-60 cells.     

A clinical trial of removal of bilirubin in blood by Evaflux-2A

We performed both free and albumin-bound bilirubin removal therapy using the Evaflux-2A and evaluated its clinical effects. The removal rates of total bilirubin in the first and second sessions were 31.4%, and 31.0%, respectively. Our clinical data suggested that plasma exchange using Evaflux-2A and an albumin-added electrolyte solution as the substitute fluid was useful in the treatment of hyperbilirubinemia.     

The cholinergic neurotoxin ethylcholine mustard aziridinium (AF64A) induces an increase in MAO-B activity in the rat brain

Recently it was reported that there is an increase in monoamine oxidase B (MAO-B) activity in post-mortem brains of patients with Alzheimer's disease. It was postulated that this increase in MAO-B activity was due to gliosis associated with neuronal degeneration. The aim of the present investigation was to evaluate the effect on MAO of neuronal degeneration primarily affecting the cholinergic system. The specific cholinergic toxin AF64A (3 and 4.5 nmol) was injected bilaterally into the cerebral ventricles of rats. We then estimated MAO-A, MAO-B, dopamine (DA) uptake rates and choline acetyltransferase (ChAT) activities in hippocampus, striatum and cortex, 1, 2.5 and 4.5 weeks after the injection. Marked long-lasting reduction in ChAT activities appeared only in hippocampus, consistent with previous reports. The MAO-A activity was unchanged as were DA uptake rates. Neither was there any change in MAO-B activity found 1 week after the injection. However, a significant increase in MAO-B activity appeared after 2.5 weeks and persisted after 4.5 weeks in all 3 brain regions investigated. This result is likely to reflect progressive gliosis after cholinergic neuronal degeneration. Previous results have shown an increased MAO-B activity with age and a further accelerated increase in Alzheimer's disease. Experimentally, hemitransection and injection of kainic acid have been shown to cause a similar increase. The present results show that changes in MAO-B activity also reflect degenerative processes in brain mainly affecting the cholinergic system.     

Topical thermal therapy with hot packs suppresses physical inactivity-induced mechanical hyperalgesia and up-regulation of NGF

We focused on the analgesic effect of hot packs for mechanical hyperalgesia in physically inactive rats. Male Wistar rats were randomly divided into four groups: control, physical inactivity (PI), PI + sham treatment (PI + sham), and PI + hot pack treatment (PI + hot pack) groups. Physical inactivity rats wore casts on both hind limbs in full plantar flexed position for 4 weeks. Hot pack treatment was performed for 20 min a day, 5 days a week. Although mechanical hyperalgesia and the up-regulation of NGF in the plantar skin and gastrocnemius muscle were observed in the PI and the PI + sham groups, these changes were significantly suppressed in the PI + hot pack group. The present results clearly demonstrated that hot pack treatment was effective in reducing physical inactivity-induced mechanical hyperalgesia and up-regulation of NGF in plantar skin and gastrocnemius muscle.     

Changes in left ventricular preload and contractility following severe burns in the dog

Summary To examine the effects of severe burns on preload and left ventricular (LV) contractility, we continuously measured LV pressures and dimensions in severely burned dogs throughout the early part of the postburn period. Hemodynamic parameters, including cardiac output (CO), mean aortic pressure (MAP), heart rate (HR), LV pressures and their first derivatives (dP/dt), and the LV regional dimension, were measured and compared before and every 30 min after burns were produced (up to 360 min) in four groups: group A (n=7), dogs with sham burns; group B (n=5), dogs with nonresuscitated full-thickness burns involving 50% of the total body surface area; group C (n=6), dogs with burns resuscitated with lactated Ringer's solution at 4 ml × kg × % burn/24 h; and group D (n=6), dogs with burns resuscitated with 1.5% dextran in lactated Ringer's solution at 2 ml × kg × % burn/24 h. From these measurements, we obtained the LV end-diastolic segment length (EDL) as an index of preload and three indices of cardiac contractility, i.e., peak dP/dt, the percentage of shortening (%L), and mean V_cf. Our results showed that CO, MAP, and preload (i.e., EDL) decreased significantly more in the three burn groups (groups B, C, and D) than in the sham burn group, but that there were no significant differences in CO, MAP, and EDL among the three burn groups. The three indices of contractility also decreased significantly more in the three burn groups than in the sham burn group. When changes in LV end-diastolic pressure (LVEDP) and EDL during the experiment were examined, apparent discrepancies were found in the changes between LVEDP and EDL in the burn-resuscitated groups (C and D); the postburn decreases in LVEDP in the burn-resuscitated groups were significantly smaller than those in the burn-nonresuscitated group, but there were no significant differences in the postburn decreases in EDL among the three burn groups. These findings indicate that: (1) the fall in cardiac output following severe burns was due to both the decreased preload and decreased LV contractility; (2) the decreased preload and LV contractility could not be restored to preburn levels by conventional fluid therapy during the 6-h experimental period; and (3) the possible decrease in LV compliance was more prominent in the burn-resuscitated groups.