Distribution of calcium in central nervous system tissues and bones of rats maintained on calcium-deficient diets

Current changing epidemiological pattern in the Western Pacific area suggests a contribution of the environmental factors to the pathogenetic process of amyotrophic lateral sclerosis (ALS). The condition of unbalanced mineral levels found in the soil and drinking water samples from the ALS foci showing low content of calcium (Ca) and magnesium (Mg) plus high content of aluminum (Al) was experimentally mimicked in this study using rats. In the groups fed low Ca, low Ca-Mg, and low Ca-Mg plus high Al diets, serum Ca levels were lower than that in the group fed the standard diet. Ca content of CNS tissues showed higher values in the unbalanced diet groups, especially in the spinal cord of low Ca-Mg plus high Al diet group, than those in the standard diet group, determined by inductively-coupled plasma emission spectrometry (ICP). Ca content in heart, liver, kidney, and abdominal aorta in groups fed low Ca-Mg, and low Ca-Mg plus high Al diets was higher than that in low Ca, and standard group. Ca content in muscle in the three unbalanced diet groups was significantly higher than in the standard diet group. Ca and Mg contents in lumbar spine and cortical bone showed lower values in the unbalanced diet groups than those values in the standard diet group. These findings suggest that under the condition of derangement of bone mineralization induced by unbalanced mineral diets fed to the experimental rats, Ca and Mg may be mobilized from bone, keeping their content in soft tissues, including CNS tissue, for utilization of vital activities, thereby resulting in a deposition of Ca while maintaining an almost normal value of magnesium in the CNS tissues.

Effect of vasopressin on cardiovascular and renal functions and ANP release under plasma volume expansion

To assess the mechanisms whereby arginine vasopressin (AVP) increases atrial natriuretic peptide (ANP) release and to examine whether AVP-mediated ANP release affects the effect of AVP on the cardiovascular and renal function, AVP was infused continuously at a rate of 20 ng.kg-1.min-1 for 75 min following 200 ng/kg bolus injection under stepwise increases in plasma volume in anesthetized dogs. Moreover, the effect of an AVP antagonist, a V1 blocker, 1-(beta-mercapto-beta, beta-cyclopentamethylenepropionic acid)-2-(o-methyl)tyrosine AVP (TMeAVP), on these parameters was also investigated. In the control study, saline alone was infused. AVP infusion increased total peripheral resistance (TPR), pulmonary capillary wedge pressure (PCWP), and plasma ANP, but decreased cardiac index (CI) and heart rate (HR) without increases in mean arterial blood pressure (MABP). Stepwise rises in plasma volume further increased plasma ANP, CVP, CI and PCWP, but gradually decreased TPR. TMeAVP curtailed AVP-induced increases in TPR and plasma ANP as well as decreases in CI and HR. The replacement of ANP to prevent a fall in plasma ANP following TMeAVP never affected cardiovascular function. AVP infusion increased plasma volume accompanied by a fall in urinary Na excretion (UNaV) and urine flow (UF) under the stepwise plasma volume expansion compared to the control group, but did not affect mean circulatory filling pressure (MCFP). ANP administration enhanced UNaV and UF and decreased MCFP. These results indicate that AVP may preferentially increases ANP release via the increased cardiac afterload, not preload, but increased plasma ANP per se may not be involved directly in the AVP-induced cardiac suppression.

[Mutual supplementation in treatment of renal failure by blood purification and kidney transplantation]

More than 100,000 uremic patients have been maintained by various blood purification modalities in Japan. However, their quality of life is far from satisfaction not only in terms of physical problems related to the complications specific to long-term dialysis treatment, but also the restriction in social activities by spending much time for hospital dialysis. A graft functioning rate in kidney transplantation has been remarkably improving after introduction of Cyclosporine A as an immunosuppressant and is presently approximately 90% one year after transplantation. As long as the transplanted kidneys function, further extensive social activities and highly-graded quality of life is warranted compared to artificial kidney treatment. On the other hand, patients in end-stage renal diseases and with rejected transplants are expected to undergo safe kidney transplantations as being maintained by dialysis therapy. Furthermore, recent development in blood purification technology has made the specific kidney transplantations successful in recipients with the preformed antibody (-ies) and the incompatible ABO blood type antibody (-ies). Nowadays, relation between blood purification and kidney transplantation is not competitive, but mutually supplementary as a matter of realism.

Presentation of autoantigen by human T cells

Activated human T cells express MHC class II and have been shown to present foreign Ag to autologous T cells. We now demonstrate that MHC class II+ T cell clones can present myelin basic protein (MBP) peptide autoantigen in the absence of traditional APC to autologous MBP reactive T cell clones. MBP peptide-pulsed T cell clones specifically stimulated autologous MBP-reactive T cell clones to flux calcium and proliferate. Activation responses were peptide epitope specific and blocked by mAb to MHC class II, indicating a TCR-mediated response. In addition, mAb to the adhesion molecules LFA-3, CD2, LFA-1, CD29, and to the tyrosine phosphatase CD45 also inhibited proliferation, indicating the involvement of T to T cell interactions. In contrast to peptide Ag, T cell clones did not respond to autologous T cells pulsed with HPLC-purified MBP, suggesting that T cells are unable to process whole MBP. However, batch-purified MBP Ag preparations containing lower m.w. breakdown products were presented by T cells, indicating that naturally occurring breakdown products of autoantigens could be presented by activated T cells in vivo. These results raise the possibility that T cell presentation of autoantigen at inflammatory sites may be important in regulation of immune responses to self Ag.

Presentation of autoantigen by human T cells

Activated human T cells express MHC class II and have been shown to present foreign Ag to autologous T cells. We now demonstrate that MHC class II+ T cell clones can present myelin basic protein (MBP) peptide autoantigen in the absence of traditional APC to autologous MBP reactive T cell clones. MBP peptide-pulsed T cell clones specifically stimulated autologous MBP-reactive T cell clones to flux calcium and proliferate. Activation responses were peptide epitope specific and blocked by mAb to MHC class II, indicating a TCR-mediated response. In addition, mAb to the adhesion molecules LFA-3, CD2, LFA-1, CD29, and to the tyrosine phosphatase CD45 also inhibited proliferation, indicating the involvement of T to T cell interactions. In contrast to peptide Ag, T cell clones did not respond to autologous T cells pulsed with HPLC-purified MBP, suggesting that T cells are unable to process whole MBP. However, batch-purified MBP Ag preparations containing lower m.w. breakdown products were presented by T cells, indicating that naturally occurring breakdown products of autoantigens could be presented by activated T cells in vivo. These results raise the possibility that T cell presentation of autoantigen at inflammatory sites may be important in regulation of immune responses to self Ag.

Prolongation of cardiac xenograft function after reduction of natural antibodies using double filtration plasmapheresis

A double filtration plasmapheresis (DFPP) technique was applied to selectively remove the natural antibodies in discordant xenotransplantation. A swine heart was heterotopically transplanted in a canine neck after two DFPP procedures during which 200 to 500 ml of plasma were replaced with the same amount of Hartman's solution containing 7% human albumin. Mean removal rate of IgC and IgM by DFPP ranged from 74.2 +/- 0.5 to 95.9 +/- 2.8%. The anti-swine lymphocytotoxic reaction of canine serum was decreased after DFPP but still remained in low titers. Mean graft survival time in the group treated by DFPP in which 1000 ml of plasma was totally replaced was prolonged to 107 +/- 47 min, while it was 9 +/- 5 min in the group without any treatment (p less than 0.01). Deposits of canine IgM and C3 on the vascular endothelium of the graft were observed on immunofluorescence, while there were no deposits of IgG. In conclusion, DFPP effectively removed the natural antibodies, resulting in prolongation of xenograft survival time. Immunofluorescence study suggested that natural IgM antibodies played an important role in this xeno-hyperacute rejection.

A case of syndrome of inappropriate secretion of antidiuretic hormone associated with diabetes mellitus

A 46-year-old man, presenting with headache, nausea, and lassitude, was diagnosed as having diabetes mellitus and hyponatremia, and admitted to Tohoku University Hospital. Insulin treatment improved the hyperglycemia but aggravated hyponatremia, which was proved to be elicited by the inappropriate secretion of antidiuretic hormone (SIADH). An acute water load failed to suppress ADH release in the supine posture but slightly increased plasma atrial natriuretic peptide (ANP). On the other hand, plasma ADH markedly increased in response to an upright posture, accompanied by a fall in blood pressure and a rise in heart rate. After treatment with droxidopa "a sympathomimetic drug", ambulatory blood pressure gradually increased and hyponatremia disappeared. However, blood pressure and ADH responses to upright posture were not improved by treatment with the drug. Moreover, plasma ADH was still not sufficiently suppressed by acute water loading in the supine position, but plasma ANP markedly increased, thereby resulting in urinary dilution and natriuresis. These results suggest that exaggerated ADH release (SIADH) was brought about by the baroreceptor reflex stimulated by the postural hypotension, and also by the impaired osmoregulation associated with diabetic neuropathy, and that droxidopa improved cardiovascular function and increased ANP release with resultant urinary dilution and natriuresis in spite of slightly increased ADH release.

[Sex hormones and calcium regulating hormones in rheumatoid arthritis]

Rheumatoid arthritis (RA) occurred frequently in women. Exogenous estrogen has been reported to alleviate the symptoms of patients with RA. But the implications of sex hormones and immunological abnormalities in RA remain to be elucidated. Therefore, we measured sex hormones (LH, FSH, estradiol, testosterone and prolactin), bone metabolic markers (midregion and carboxy terminal mainly recognized PTH1-84, intact PTH1-84, bone GLA protein and alkaline phosphatase), bone mineral, in lumbal bone with quantitative tomography (QCT) and with of cortex with microdensitometry in 52 females with RA and 46 females with osteoarthritis (OA) as a control group. Sex hormones and bone metabolic markers were analyzed as independent variables of serum LH, FSH and estradiol levels, using one way analysis, in patients with RA and OA. The more increased serum FSH and LH levels were, the more decreased serum estradiol levels were in both RA and OA groups, when they were considered as independent variables. These results indicate that the secretory function of pituitary and ovary axis hormones are normally enacted in RA. On the other hand, when the sex hormones of the patients under 53 years of age were studied in both groups, serum FSH adn LH showed significantly higher levels, while serum estradiol levels revealed decreased tendency in RA, compared with these in RA. Thus the pituitary ovary secretory function in patients with RA was suggested to be disturbed in early stage of age, indicating that the sex hormones would be partly implicated in calcium and bone metabolism in patients with RA.

Involvement of ovarian steroids and endogenous opioids in the fasting-induced suppression of pulsatile LH release in ovariectomized rats

The participation of the ovarian steroids and opioid peptides in the suppression of pulsatile LH release during acute fasting was examined in rats. Ovariectomized rats bearing silicone elastomer implants of oestradiol and/or progesterone were fasted for 48 h and subsequently blood samples were taken every 6 min for 3 h. Pulsatile LH release was suppressed after 48 h of fasting in the ovariectomized rats implanted with oestradiol but not in the oil-implanted controls. This suppression was enhanced after the administration of progesterone together with oestradiol. In a second experiment, ovariectomized rats bearing implants of oestradiol or oil were fasted for 48 h and injected s.c. (2.5 mg/kg body weight) with an opioid antagonist, naloxone hydrochloride, immediately before blood sampling. In the fasted oestradiol-treated ovariectomized rats, naloxone was able to prevent the suppression of pulsatile LH release. In the absence of oestradiol, however, naloxone was without effect on LH release in either the fasted or unfasted animals. These experiments indicate that the suppression of pulsatile LH release after 48 h of fasting is dependent upon oestradiol and that endogenous opioids are involved in the suppression.

[Evaluation of magnesium, calcium and aluminum deposition in bone in situ]

Current changing epidemiological pattern in the Western Pacific strongly suggests a contribution of the environmental factors to the pathogenetic process of amyotrophic lateral sclerosis (ALS). As a reflection of excess metals and a deficiency of minerals in soil and water samples in these foci, this study was designed experimentally to evaluate the concentration of calcium (Ca), magnesium (Mg) and aluminum (Al) in the bones of rats fed unbalanced mineral diets. Twenty-eight male Wistar rats, weighing 200 g, were fed either a standard diet, a low Ca diet, a low Ca-Mg diet, or a low Ca-Mg diet with high Al for 90 days. The composition of the diet/100 g consists of Ca 1250 mg, Mg 300 mg, Al 10 mg, Zn 4 mg in the standard diet; Ca 3 mg and Mg 2 mg in the low Ca-Mg diet; and Al 194 mg in the high Al diet, Al supplied as Al lactate. Ca, Mg and Al concentrations were determined by using inductively coupled plasma emission spectrometry (ICP) for bone and atomic absorption spectrometry for serum. Serum Ca levels in the groups fed unbalanced mineral diets were lower than those in the group fed standard diet. Serum Mg levels were markedly decreased in the groups fed low Ca-Mg diet and low Ca-Mg plus high Al diet, compared with those in the groups fed standard diet and low Ca diet.(ABSTRACT TRUNCATED AT 250 WORDS)

[Chronic lymphocytic leukemia with peripheral T lymphocytes expressing CD 2+, CD 3+, CD 4-, CD 8-, CD 16+, and CD 56+ and lymph-node lymphocytes expressing CD 2+, CD 3-, CD 4-, CD 8-, CD 16+, CD 38+, and CD 56+]

A 33-year-old man was hospitalized because of thrombocytopenia and severe splenomegaly. On admission 78% of peripheral lymphoid cells were abnormally large, with pale cytoplasm. Flow cytometry of the abnormal lymphocytes showed that they expressed CD 2, CD 3, CD 11, CD 16, and CD 56, but not CD 4 nor CD 8, so they were T-cell large granular lymphocytes (T-LGL). Abnormal lymphocytes obtained from a lymph node expressed CD 2, CD 16, CD 38, and CD 56, but not CD 3, CD 4, and CD 8, so they were natural killer(NK) cells. Splenectomy was performed and the operative specimen showed diffuse infiltration of pleomorphic lymphocytes, probably chronic lymphocytic leukemia cells. After splenectomy, the platelet count returned to normal but the lymphocytosis continued. Two years after discharge, chemotherapy was done because of thrombocytopenia and hepatomegaly. The patient died of disseminated intravascular coagulation arising from sepsis. The differences and similarities between peripheral and lymph-node lymphocytes suggest that LGL and NK cells may be differentiated from the same kind of cell, somewhat differentiated from stem cells.

Cyclical edema in a patient with hypothalamic disorders and chronic glomerulonephritis: arginine vasopressin-dependent atrial natriuretic hormone release

A 28-year-old woman had hypothalamic disorders (amenorrhea, obesity, psychiatric abnormalities, polydipsia and fever) and chronic glomerulonephritis. She also suffered from general edema associated with cyclical oliguria and polyuria. Her body weight and plasma osmolality increased during the oliguria phase lasting 2 to 8 days and decreased after paroxysmal polyuria accompanied by the natriuresis. These episodes occurred repeatedly, regardless of the treatment with or without diuretics. The release of arginine vasopressin in response to increased plasma osmolality was exaggerated, but changes in plasma volume did not affect arginine vasopressin release. Plasma atrial natriuretic hormone increased in response to a rise in plasma arginine vasopressin and plasma volume during the oliguria phase, thereby resulting in the diuresis and natriuresis. The renin-angiotensin-aldosterone system was secondarily activated by body fluid depletion and diuretics, and this might play an additive role in general swelling. Plasma gonadal hormones did not change to explain the edema. The mechanism of this cyclical edema remains unknown, but it is likely that hypothalamic dysfunction related to psychiatric abnormalities may exaggerate arginine vasopressin release, and enhanced renal sympathetic activity may cause retention of Na and water, and the increase in atrial natriuretic hormone release responding to the plasma volume expansion may bring about the diuresis and natriuresis.

[A case of small cell carcinoma of the lung responding well to oral etoposide therapy]

A case of recurrent small cell carcinoma of the lung, accompanied by intraperitoneal metastasis, was orally treated with etoposide (50 mg/day) for 3 consecutive weeks. Subjective symptoms such as abdominal pain began to improve one week after the start of treatment. After three weeks of treatment, these symptoms disappeared completely, and CT findings also improved. The serum NSE level, which was as high as 89.5 ng/ml before treatment, fell to 8.7 ng/ml after 3 weeks of treatment. The patient is now being followed at the outpatient clinic of our hospital. As adverse reactions to the drug, alopecia and leukopenia were observed. The leukopenia appeared in the third week of treatment, but the white blood cell count returned to normal soon after the drug was discontinued.

Glucocorticoid-induced central diabetes insipidus in a case of malignant lymphoma

A 37-year-old man was diagnosed as malignant lymphoma infiltrating in the central nervous system with hypopituitrism and secondary glucocorticoid deficiency. In this case, plasma arginine vasopressin (AVP) increased, but glucocorticoid administration decreased plasma AVP and increased urine volume with a reduction in urinary osmolality, indicative of the presence of glucocorticoid-induced diabetes insipidus. At the terminal stage, plasma AVP did not increase in response to the withdrawal of glucocorticoid and urine volume remained decreased, suggesting the presence of masked diabetes insipidus. Autopsy showed an infiltration of lymphoid cells around the cerebral ventricles and necrosis in the hypothalamo-hypophyseal system. These findings suggested that glucocorticoid might centrally play an important role in the regulation of AVP release, and its deficiency potentiated AVP release.

Responses of atrial natriuretic peptide, vasopressin, aldosterone and renal function to intracerebroventricular infusion of angiotensin II in dogs

To assess the mechanisms how angiotensin II (Ang II) given intracerebroventricularly (i.c.v.) induces natriuresis, the effects of Ang II (10 ng/kg/min, for 30 min) on the renin-angiotensin-aldosterone system, the release of vasopressin (AVP) and atrial natriuretic peptide (ANP) and on cardiovascular and renal functions were investigated in anesthetized dogs. In control dogs, vehicle alone (artificial cerebrospinal fluid) was infused at a rate of 10 microliters/min. Ang II given i.c.v. produced a gradual increase in urine flow, urinary sodium and potassium excretion and osmolar clearance, but had no effect on plasma ANP, aldosterone, arterial blood pressure, and renal blood flow. However, i.c.v. Ang II increased plasma AVP and decreased heart rate, plasma renin activity, inulin clearance and filtration fraction. In the cotrol group, vehicle treatment had no effect on these parameters except for decreases in inulin clearance and filtration fraction. These results suggest that circulating ANP and blood pressure may not play an important role in i.c.v. Ang II-induced natriuresis, but increased AVP release and decreased renal sympathetic nervous activity may contribute to the natriuresis.

[Timing of administration of granulocyte colony stimulating factor after cytotoxic chemotherapy in hematological malignancies]

We evaluated the effects of recombinant human granulocyte colony stimulating factor (rhG-CSF) given to 30 patients with hematological malignancies after cytotoxic chemotherapy. The first course of chemotherapy was not treated with rhG-CSF (control), and in the second to fourth courses, rhG-CSF was given by one of the following three ways to the patients (not necessarily in this order): 1) 10 days of administration starting 48 hr after chemotherapy, 2) 5 days of administration starting 48 hr after chemotherapy, and 3) 5 days of administration after the leukocyte counts reached to less than 2,000/microliters. The leukocyte nadirs were significantly higher in the course with 10 days of administration compared with the control course. The time needed for recovery from the leukocyte nadir was significantly shorter in 10-day course and 5-day course after the leukocyte counts reached to less than 2,000/microliters. The therapy spans became significantly shorter with all of the three patterns of administration of rhG-CSF compared with the control course. The number of days on which the leukocyte counts became less than 2,000/microliters were significantly fewer in 10-day course and 5-day course after the leukocyte counts became less than 2,000/microliters. These findings showed that rhG-CSF prevented severe neutropenia after cytotoxic chemotherapy, and (or) assisted the rapid recovery from neutropenia. These effects depend on the timing of its administration.

[Transient focal abnormalities of MRI and angiographic neuroimaging in status epilepticus: case report]

We reported transient changes in computed tomography (CT), angiography and magnetic resonance imaging (MRI) scans in a patient with status epilepticus, referred to us with a tentative diagnosis of neoplasma based on CT, MRI and angiographic findings, MRI showed increased signal intensity, and CT showed decreased left hemisphere attenuation without enhancement. Two months later, resolution of these radiological and clinical abnormalities had been attained. The transient CT and MRI changes probably represented focal cerebral edema, developing during focal status epilepticus.

[A new multiple organ preservation-assessment of viability after the heart and lung preservation using UCLA formula]

The difficulty in obtaining suitable organs for the transplantation is a major problem in Japan. In this study, we assessed the suitable procedure for multiple organ preservation and evaluated organ viabilities after preservation with an unique technique. The heart and lung were preserved with UCLA Formula alone and the liver was preserved with Euro-Collins' solution. The mean ischemic times of the heart, lung and liver were 4.3 hours, 7.5 hours, and 6 hours, respectively. The viability of the heart graft following orthotopic transplantation was evaluated with cardiac output and Left Ventricular End-Diastolic Pressure (LVEDP) under the constant pre-load (CVP 7 mmHg). Cardiac outputs (ml/min.) were 4.01 +/- 1.36 before operation, 3.26 +/- 0.26 at 1 hour after transplantation, 3.24 +/- 0.26 at 4 hours after transplantation (NS). LVEDP (mmHg) was 7.1 +/- 0.8 before operation, 6.5 +/- 0.86 at 1 hour, and 7.4 +/- 1.2 at 4 hours after transplantation (NS). The viability of transplanted lung was evaluated with pressure-tidal volume curve and arterial oxygen tension (PO2) when right pulmonary artery and bronchus were occluded. There was no statistical difference in pressure-volume curve and PO2 tension between the phases of pre- and post-transplantation. After liver transplantation, ICG test (15 min.) showed a sufficient value of 35-40%. In conclusion, the procedures of multiorgan preservation using UCLA Formula and Euro-Collins' solution were successfully performed and its viability of grafts after transplantation remained sufficient.

Effects of ubenimex, a biological response modifier, on myelodysplastic syndrome and chronic leukemia

Twenty cases of myelodysplastic syndrome (MDS) were treated with ubenimex. Seventeen cases were treated with the drug over 90 d. Among these, 10 showed improvement of anemia, 12 an increase in platelet count which had decreased before treatment and 10 an increase in neutrophil count; however, 14 showed an increase in blast percentage in bone marrow aspirate. CD4/CD8 ratio was increased in 4 cases and shifted to a normal from an abnormal range in 6 cases. When the MDS cases were observed in refractory anemia (RA) and refractory anemia with excess blasts (RAEB), great improvement was seen, but in RAEB increase in blast percentage was also observed. CD4 increased mostly in RA and CD8 increased in RAEB. Ten cases of chronic myelocytic leukemia (CML) were first treated with ubenimex and cytostatics, then with ubenimex only. Six cases attained partial remission within 3 months, but one case showed a marked increase in white cell count and blast count and in another case a progression of splenomegaly associated with increase in white cell count. From these findings we conclude that ubenimex could be utilized in MDS or CML if the patient was at risk for strong chemotherapy.

Review of ubenimex (Bestatin): clinical research

An immunomodulating agent, ubenimex (Bestatin) has low toxicity even after long-term oral administration and brings about significant modifications in immunological response. In a cooperative randomized controlled study of Bestatin immunotherapy for adult acute nonlymphocytic leukemia, prolongation of remission duration and survival was achieved with Bestatin immunotherapy combined with remission maintenance chemotherapy. The significant prolongation of remission duration and survival was seen in the Bestatin group, especially in the elderly patients. Randomized controlled studies of Bestatin immunotherapy were performed in solid tumors including malignant melanoma, carcinoma of the lung, stomach, bladder, head and neck and esophagus, and therapeutic benefits regarding disease free-interval or survival were observed in certain types of the above-mentioned cancers; however, Bestatin immunotherapy for these cancers should be further investigated in large-scale controlled studies to confirm its activity.