Polyclonal B cell activation and autoimmunity in New Zealand mice. I. Natural thymocytotoxic autoantibody (NTA)

The present genetic studies were designed to investigate a possible correlation of spontaneous polyclonal activation of B cells with the spontaneous production of natural thymocytotoxic autoantibody (NTA) in female (NZB X NZW)F1 X NZW backcross mice. We analyzed the spontaneous polyclonal activation of B cells by determining the serum level of naturally occurring anti-hapten (dinitrophenyl, DNP) IgM antibodies. Based on comparisons of the magnitude of the serum DNP binding activities among NZB, NZW, the F1, and the backcrosses to NZW mice, we found that the abnormal polyclonal activation of B cells depends largely on the contribution of NZB genomes. Similar observations were made on serum IgM levels in these mice, and there were made on serum IgM levels in these mice, and there was a highly significant correlation between these two measures in the backcross mice. Despite striking similarities in several observations between NTA and the anti-DNP antibodies, as well as the serum IgM level, there was no significant correlation between the spontaneous production of NTA and the abnormal levels of the anti-DNP antibodies and serum IgM in the backcross mice in both quantitative and qualitative analyses. We also found no significant association between these polyclonal activation of B cells and H-2 complex.

Polyclonal B cell activation and autoimmunity in New Zealand mice. I. Natural thymocytotoxic autoantibody (NTA)

The present genetic studies were designed to investigate a possible correlation of spontaneous polyclonal activation of B cells with the spontaneous production of natural thymocytotoxic autoantibody (NTA) in female (NZB X NZW)F1 X NZW backcross mice. We analyzed the spontaneous polyclonal activation of B cells by determining the serum level of naturally occurring anti-hapten (dinitrophenyl, DNP) IgM antibodies. Based on comparisons of the magnitude of the serum DNP binding activities among NZB, NZW, the F1, and the backcrosses to NZW mice, we found that the abnormal polyclonal activation of B cells depends largely on the contribution of NZB genomes. Similar observations were made on serum IgM levels in these mice, and there were made on serum IgM levels in these mice, and there was a highly significant correlation between these two measures in the backcross mice. Despite striking similarities in several observations between NTA and the anti-DNP antibodies, as well as the serum IgM level, there was no significant correlation between the spontaneous production of NTA and the abnormal levels of the anti-DNP antibodies and serum IgM in the backcross mice in both quantitative and qualitative analyses. We also found no significant association between these polyclonal activation of B cells and H-2 complex.

Effects of oral feeding of mite antigen upon production of homocytotropic antibodies

Effect of oral administration of mite antigen was studied in homocytotropic antibody production in mice. Anti-mite IgE and IgG, antibodies were undetectable if the large amount of mite antigen was given prior to primary immunization. It was noted that the larger the dosage given the more clearly the suppression of homocytotropic antibody production was obtained and the shorter the interval between feeding and primary immunization the more marked tolerance was induced. No significant effect was observed by oral administration of antigen in on-going homocytotropic antibodies.

Tryptophan and indolic tryptophan metabolites in chronic renal failure

Tryptophan and indolic tryptophan metabolites were measured in the serum of normal subjects and chronic renal failure patients. The tryptophan free/total ratio was 0.07 in the normal serum, but the other tryptophan metabolite values were below detectable levels. The free/total ratio was 0.66 in patients with chronic renal failure, and both increase of free tryptophan and decrease of total tryptophan were observed. At the same time, 5-hydroxyindoleacetic acid, indole acetic acid, 5-hydroxytryptophol, and N-acetyltryptophan also increased in the serum of chronic renal failure patients, existing not only in free form but in protein-bound form. In the serum samples, following hemodialysis the indolic tryptophan metabolites showed a tendency to decrease, and the tryptophan free/total ratio of 0.42 a approached the normal value. When indolic tryptophan metabolites were added to normal serum in vitro, the free tryptophan level rose, and competition for binding to albumin between tryptophan and indolic tryptophan metabolites was observed. These findings suggested that the cause of the decrease in protein-bound tryptophan in uremic serum may be an accumulation of indolic tryptophan metabolites which complete for binding to albumin in uremia.

Hemodiafiltration with sodium concentration-controlled dialysate

When hemofiltration and hemodialysis are compared, the former is more effective in removing larger substances, whereas the latter is superior in removing small substances. We consider hemodiafiltration, in which the advantages of the two treatment methods can be adopted, as the most effective and practical method. In the studies of hemodiafiltration, we demonstrated that disequilibrium syndrome associated with the treatment can be prevented by employing a high sodium concentration in the dialysate. The dialysate was successfully used for treating intracellular overhydration. However, it could not be used without causing adverse effects such as thirst in patients whose intracellular overhydration had already been treated and resulted in increase in their body weight. However, these patients were treated successfully by decreasing the high sodium concentration gradually or in a stepwise manner.

Effects of ticlopidine on thrombotic obstruction of A-V shunts and on dialysance of artificial kidneys

Administration of ticlopidine, a new inhibitor of platelet aggregation, during hemodialysis to two patients with thrombotic occlusion of external A-V shunts markedly suppressed the obstruction of the shunt and improved anemia. Consequently, it was concluded that this drug may be useful for maintaining good blood flow and good patency of shunts in patients undergoing dialysis. In order to determine the dialyzer efficiency during dialysis, the reduction rate of the dialyzer was determined in vitro. The dialyzer reduction rates for urea, creatinine, uric acid, and phosphoric acid were all lowered after dialysis, and the administration of ticlopidine resulted in a suppression of the drop in the reduction rate. Based on the inhibitory effect of ticlopidine on platelet aggregation, it was assumed that a close correlation may exist between adhesion and aggregation of platelets and the drop in the efficiency of the dialyzer during dialysis as well as thrombotic obstruction of shunts.

Topographic distribution pattern of Lafora-like bodies in the spinal cord of some animals

The topographic distribution pattern and morphological features of Lafora-like bodies in the spinal cord of the dog, cat, fox, and baboon were examined by light and electron microscopy. The caudal lumbar and the coccygeal parts of the spinal cords were the predilection sites for the bodies in all animals and were very prominent in the ventral columns and intermediate substance. The bodies mainly composed of branching filaments were preferentially located in neuronal processes and rarely in astocytes. The histochemical characteristics of the bodies were identical in all animals and consisted mainly of polyglucosan.

Human IgE, IgG and IgE antibody synthesis in vitro

Human IgE biosynthesis in vitro was studied by co-culturing T and B cells from atopic patients and normal controls in the presence of 10 microliter/ml pokeweed mitogen for 7 days. IgE and anti-mite IgE ab in the culture media significantly correlated with those in plasma. Normal T cells suppressed in vitro production of IgE and IgE ab significantly more than did atopic T cells but no difference was found in IgG production. The culture of B cells alone (T-depleted fraction) produced IgE equally as well as the co-culture of T and B cells. Anti-mite IgE ab was also produced by B cells alone from mite-sensitive patients. However, IgE biosynthesis in vitro was not consistently affected by pokeweed mitogen. The results suggest a deficiency of the T suppressor system in atopy and the existence of T-independent IgE-producing cells.

Biochemical alterations of connective tissue metabolism in the arterial walls of stroke-prone spontaneously hypertensive rats

1. The chemical characteristics of the vascular connective tissue components were determined in stroke-prone (SP), stroke-resistant (SR) spontaneously hypertensive (SH) rats and normotensive Wistar-Kyoto (WK) rats. 2. The ratio of hydroxylysine to hydroxylsine plus lysine in the vascular collagen was increased in 6-month-old SP-SH rats and SR-SH rats as compared with WK rats. 3. An age-related increase in uronic acid and hexose content of the aorta was noted in SP-SH, SR-SH and WK rats. However, the increase was more prominent in SH rats, especially SP-SH rats at the stages examined (11 weeks and over 8 months of age). 4. The ratio of galactosyl-hydroxylysine to glucosyl-galactosyl-hydroxylysine in the aortic collagen was decreased in 6-month-old SH rats, especially SP-SH rats as compared with WK rats. 5. A relative increase in beta and gamma components in aortic collagen was noted in 6-month-old SP-SH rats when compared with SR-SH rats. 6. The increased content of uronic acid and hexose and the structural changes of vascular collagen as demonstrated in SP-SH rats might be related to the fragility of the arterial wall and/or to the pathogenesis of stroke-proneness.

Problems with activated charcoal and alumina as sorbents for medical use

Although activated charcoal and alumina have been used extensively as sorbents in uremic patients, the following problems remain to be solved: 1) elution of SO4--from activated charcoal which does not adsorb it; 2) production of methylguanidine from creatinine on the surface of activated charcoal; 3) production of lipoperoxide from fatty acids by chemical reaction of activated charcoal; 4) adsorption of Ca++ and Mg++ when alumina adsorbs inorganic phosphate. These problems are studied in vitro and clinically.

Chemical analysis of vascular collagen in stroke-prone spontaneously hypertensive rats

Chemical characteristics of vascular collagen were studied in stroke-prone spontaneously hypertensive rats (SHRSP) which developed cerebrovascular lesions spontaneously in over 90% of the population. Aminoacid analysis of arterial collagen among SHRSP showed no remarkable difference from stroke-resistant SHR (SHRSR) and normotensive Wistar-Kyoto rats (WK). The uronic acid content of the aorta, which elevated with aging, was increased in SHRSR and especially in SHRSP. The hexose content of collagen was also increased in SHRSP characteristically with a concomitant increase in the ratio of the disaccharide unit (glucosyl-galactosyl-hydroxylysine) to the monosaccharide (galactosyl-hydroxylysine). The relative increase in beta and gamma components was also noted in SHRSP. These structural changes of vascular collagen especially noted in SHRSP may be related to the fragility of arterial wall or to the stroke-proneness.

Lafora-like bodies in a cat. Case report suggestive of glycogen metabolism disturbances

Lafora-like bodies in an 8-year-old cat were studied light and electron microscopically and histochemically. In addition ot Lafora-like bodies composed of branching filaments, glycogen granules and electron-dense materaisl, abnormal accumulations of glycogen granules attracted attention. The most remarkable features were the developmental processes of the branching filaments originating directly from glycogen granules. Lafora-like bodies in the present study showed ultrastructural, histochemical, and enzymatic similarities to those described in the previous reports in Lafora's disease, glycogenosm is considered to be probably related to the productive mechanism of Lafora-like bodies.

Correlative studies of axonal spheroids and Lafora-like bodies in aged dogs

The gracile nucleus and conus medullaris, the sites of predilection for spheroids and Lafora-like bodies, were examined light and electron microscopically in 91 dogs ranging from 1 month to 19 years of age. The number of both structures showed a tendency to increase with age. Spheroids have already been found in younger dogs before the appearance of Lafora-like bodies. In the aged dog, intra-spheroidal Lafora-like bodies were occasionally observed. Correlative studies may yield clues on the pathogenesis of aging phenomena in the CNS.

A gas chromatographic-mass spectrometric assay for nine hydroxyphenolic acids in uremic serum

A mass fragmentographic method for the determination of m-hydroxybenzoic acid, p-hydroxybenzoic acid, o-hydroxyphenylacetic acid, m-hydroxyphenylacetic acid, p-hydroxyphenylacetic acid, vanillic acid, p-hydroxymandelic acid, homovanillic acid and vanilmandelic acid in uremic serum is described. The hydroxyphenolic acids were extracted from one ml of serum ultrafiltrate. After trimethylsilylation, the extract was analyzed by a gas chromatograph-mass spectrometer. Concentrations of nine hydroxyphenolic acids are higher in uremic serum. In particular, p-hydroxybenzoic acid and p-hydroxyphenylacetic acid are markedly increased in uremic serum. The influence of hemodialysis on the hydroxyphenolic acids was studied by quantitating the acids before and after hemodialysis.

Fluctuation of lipid peroxides and related enzyme activities at time of stroke in stroke-prone spontaneously hypertensive rats

The levels of lipid peroxides, determined as thiobarbituric acid reactive substances (TBARS), and the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), were examined in the blood from stroke-prone spontaneously hypertensive rats (SHRSP), with and without cerebral lesions, and normotensive Wistar Kyoto (WK) rats. The levels of TBARS in the blood from healthy SHRSP were not significantly different from those of WK rats, while the values of SHRSP (male) with stroke were more than twice as high as those of healthy SHRSP. The activities of SOD and GSH-Px in stroke SHRSP were also statistically different from those of healthy SHRSP.

Ion-exchange chromatographic separation and fluorometric detection of guanidino compounds in physiologic fluids

A high-performance liquid chromatographic procedure has been developed for the separation and fluorometric detection of guanidino compounds in physiologic fluids. All guanidino compounds were separated on a 17 X 0.46 cm cation-exchange column using a stepwise pH gradient. The chromatographic system was designed to enable the use of the specific reagent 9,10-phenanthrenequinone as a means of monitoring the guanidino compounds of physiologic fluids. This new analytical method is so sensitive that it enables the analysis at the picomole level. Our automatic guanidino-compound analyzer was successfully applied to the quantitative determination of all guanidino compounds in physiologic fluids from normal controls and uremic patients.

Quantitative analysis of methylguanidine and guanidine in physiologic fluids by high-performance liquid chromatography-fluorescence detection method

A rapid and sensitive high-performance liquid chromatographic method has been developed for the quantitative analysis of methylguanidine and guanidine in physiological fluids. These quanidino compounds are separated on a 6 x 0.23 cm cation-exchange column with 0.5 M sodium hydroxide solution. The guanidino compounds are detected with a fluorometer, which monitors the fluorescent guanidine derivatives produced by the reaction of the eluted constituents with 9,10-phenanthrenequinone. Sensitivity to sub-nanomole levels of methylguanidine and guanidine is demonstrated. The method was successfully applied to physiological fluids such as serum and cerebrospinal fluid from uremic patients.

Production of prostacyclin-like substance in stroke-prone and stroke-resistant spontaneously hypertensive rats

Activities of aortae to produce prostaglandin (PG) I2-like substance in stroke-prone spontaneously hypertensive rats (SHRSP), stroke-resistant SHR (SHRSR) and normotensive control rats from the Wistar-Kyoto (WK) colony were compared. PGI2-like substance was produced by the incubation of the aortic ring in pH 9.0 borate-buffered saline and the amount produced was estimated by comparison of its anti-aggregatory activity with that produced by known amounts of the sodium salt of synthetic PGI2. Before the development of stroke, amounts of this substance generated in SHRSP and SHRSR were significantly higher than those in WK rats (p less than 0.01 and p less than 0.02, respectively). Remarkably reduced capacity to generate PGI2-like substance was observed in some SHRSP after the development of stroke.

Biomembrane characteristics in stroke-prone spontaneously hypertensive rats (SHRSP)

Biomembrane characteristics in stroke-prone SHR (SHRSP) and stroke-resistant SHR (SHRSR) were examined using erythrocytes as a simplified model. When erythrocytes were exposed to osmotic stress in the process of the migration from a higher to a lower osmotic gradient by the coil planet centrifugation, erythrocytes from SHRSP were hemolyzed at a higher osmotic pressure than those from SHRSR. Such a difference in biomembrane characteristics may be useful for detecting a genetic disposition of stroke.

Glucose metabolism in spontaneously hypertensive rats

Serum glucose levels in SHR (especially SHR selected for a greater hyperglycemic response) tended to be higher at 'fasting' and were significantly higher after peroral glucose administration than those in normotensive WK. However, plasma immunoreactive insulin was not decreased in SHR as compared with WK. No significant acceleration of gluconeogenesis was observed in SHR.