Temporal analysis of cellular cytotoxicity and humoral factors during progession and regression of Rous sarcomas in Japanese quails.

Temporal appearance of cellular cytotoxicity and humoral activities including blocking and arming activities during the entire course of Rous sarcoma development in Japanese quails was examined by microcytotoxicity assay with comparison of animals bearing regressing tumors induced by a moderate dose of virus (regressors) and animals bearing growing tumors induced by a large dose of virus (progressors). Cellular cytotoxicity of the spleen cells in regressors was detected in a biphasic pattern; the first phase being observed as early as 3-5 days post inoculation (p.i.), followed by an eclipse period between 7-10 days p.i. which was the time of active tumor growth, and the second phase occurring after 12 days p.i. when the tumor had attained the maximum size. In progressors, only the first phase was observed. Instead, a stimulatory effect of the spleen cells on growth of target cells was noticed. Arming activity which confers cytotoxic activity on the normal spleen cells was demonstrated in the sera of regressors in the similar biphasic pattern as the cellular cytotoxicity; the early activity being present at 3 days p.i., and the late one after 19 days p.i. The former was detected by pre-incubation of serum with effector cells in microcytotoxicity assay and the latter by pre-incubation with target cells. In progressors, only the early arming activity which reacts with effector cells was demonstrated. Blocking activity which abrogates cellular cytotoxicity was demonstrated in both regressors and progressors but in different patterns of appearance, that is, blocking activity in regressors was only transiently demonstrated only by pre-incubation with effector cells at the time of maximum tumor growth, while the activity in progressors seemed to persist after the tumor reached the maximum size. Since the earlier activity was found to be effective at effector cell level, and the later one at both effector and target cell levels, participation of blocking factors of different types in progressors was also suggested.     

Generation of a chimeric human and simian immunodeficiency virus infectious to monkey peripheral blood mononuclear cells.

We constructed five chimeric clones between human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIVMAC) and four SIVMAC mutants by recombinant DNA techniques. Three chimeric clones and all mutants with an alteration in either the vif, vpx, vpr, or nef gene were infectious to human CD4-positive cell lines. The susceptibility of macaque monkey peripheral blood mononuclear cells (PBMC) to infection by these mutants and chimeras was examined in vitro. Macaque PBMC supported the replication of wild-type and vpx, vpr, and nef mutant SIVMAC strains. A chimera carrying the long terminal repeats (LTRs), gag, pol, vif, and vpx of SIVMAC and tat, rev, vpu, and env of HIV-1 was also replication competent in PBMC. In contrast, HIV-1, the vif mutant of SIVMAC, a chimera containing rev and env of SIVMAC, and a chimera containing vpx, vpr, tat, rev, and env of SIVMAC did not grow in PBMC. Western immunoblotting analysis of the replicating chimera in PBMC confirmed the hybrid nature of the virus. These data strongly suggested that the sequence important for macaque cell tropism lies within the LTR, gag, pol, and/or vif sequences of the SIVMAC genome.     

Production of endothelin-1 from the mesenteric arteries of streptozotocin-induced diabetic rats

Release of endothelin-1 (ET-1) from the mesenteric arteries of Wistar rats with streptozotocin-induced diabetes (STZ-DM) rats and nondiabetic rats was measured by a specific enzyme immunoassay following purification using an immunoaffinity column. The mesenteric arteries from STZ-DM rats released a significantly higher amount of ET-1 as compared to control rats (35.8 +/- 2.8 vs 14.9 +/- 2.0 pg/1hr, p less than 0.05). The plasma level of ET-1 in STZ-DM rats was also elevated to a significant extent as compared to controls (5.1 +/- 0.4 vs 3.0 +/- 0.4 pg/ml, p less than 0.05). The systolic blood pressure of STZ-DM rats was significantly higher than of the controls (p less than 0.05). The increased level of plasma ET-1 as well as its release from the mesenteric artery of STZ-DM rats may suggest its release following damage to the endothelium caused by diabetes and/or by associated changes in blood pressure.     

Changes in aerobic and anaerobic ATP-synthesizing activities in hypoxic mouse brain

The changes in cerebral metabolism in mice in severe hypoxia were investigated by analyses of changes in the levels of energy metabolites and near-infrared spectrophotometric assessment of the states of hemoglobin and cytochrome oxidase. Under 4.4% O2, the contribution of anaerobic ATP production was at most about 20% of the demand. However, the cerebral ATP level was kept at the control level until about 1 min before death. Pentobarbital anesthesia, which reduced the cerebral rate of metabolism, prolonged the survival time, although anaerobic ATP production still did not support ATP demand. Under these conditions, deoxygenation of hemoglobin and reduction of cytochrome oxidase proceeded rapidly within 1 min. Hemoglobin reached the maximum state of deoxygenation in the middle phase of hypoxia, with no further change until death. However, cytochrome oxidase was reduced slowly with one phase of partial reoxidation due to increase of cerebral blood volume, and reached the completely reduced state at death. From these results it was concluded that the aerobic ATP synthesis, which supplied more than 80% of the cerebral demand, decreased gradually because of limitation of oxygen supply, and that the failure of oxidative phosphorylation to meet demand triggered the decrease in the cellular ATP level that led to death.     

Maternal inheritance of deleted mitochondrial DNA in a family with mitochondrial myopathy

Skeletal muscles from a mother and her daughter both with chronic progressive ophthalmoplegia were analyzed. Histological and biochemical analyses of their muscle samples showed typical features of this type of mitochondrial myopathy. Southern blot analysis revealed that, in both patients, there were two species of mitochondrial DNA (mtDNA): normal one and partially deleted one. The sizes of the deletion were different; the mutant mtDNAs from the mother and the daughter had about 2.5- and 5-kilobase deletions, respectively. The two mutant mtDNAs shared a common deleted region of 1.2-kilobase. However, both the start and the end of deletion were different between them, implying a novel mode of inheritance. This is the first report that the mutant mtDNA is responsible for the maternal inheritance of a human disease.     

Provocation of a paradoxical growth hormone response to corticotropin-releasing hormone by pretreatment with metoclopramide in patients with acromegaly and normal subjects

Two of 7 patients with acromegaly and one of 7 normal subjects exhibited a paradoxical rise in growth hormone (GH) to human corticotropin-releasing hormone (CRH) when pretreated with metoclopramide, although CRH alone did not induce an increase in GH. In one of these two patients with acromegaly, the GH increase to metoclopramide alone also reached the criteria of a paradoxical response. These two acromegalic patients showed a GH increase to metoclopramide pretreatment before and up to two months after surgery. In another acromegalic patient, whose GH level remained high 5 months after surgery, metoclopramide induced an increase in GH level, while in a patient who had an above-normal GH level 18 months after surgery, the resumption of physiological GH secretion after surgery was evidenced by a postoperative absence of a GH response to metoclopramide. It is suggested from these results that the GH response to metoclopramide and the metoclopramide-provoked GH response to CRH in patients with acromegaly result from the secretion of GH from nonadenomatous cells of the pituitary.     

Clinical significance of serum bone Gla protein and urinary gamma-Gla as biochemical markers in primary hyperparathyroidism

The serum bone Gla-protein (BGP) and urinary gamma-carboxyglutamic acid (gamma-Gla) levels were determined in patients with primary hyperparathyroidism (PHP). The mean serum BGP and urinary gamma-Gla levels were 18.6 +/- 2.34 ng/ml and 65.5 +/- 4.62 nmoles/mgCr, respectively, for the 11 patients with the skeletal type of PHP, 5.13 +/- 0.85 ng/ml and 45.2 +/- 1.33 nmoles/mgCr for the 4 with the chemical type, and 7.91 +/- 2.43 ng/ml and 43.2 +/- 3.47 nmoles/mgCr for the 5 with the renal type. Thus, patients with skeletal-type PHP had significantly higher serum BGP and urinary gamma-Gla levels than those with the other type of PHP. Serum BGP levels had significant positive correlations with serum Ca (r = 0.64, P less than 0.005), serum A1-p (r = 0.77, P less than 0.001) and serum PTH (r = 0.45, P less than 0.005). Urinary gamma-Gla levels also had significant positive correlations with serum Ca (r = 0.50, P less than 0.05), serum A1-p (r = 0.67, P less than 0.005), serum 1,25(OH)2D (r = 0.62, P less than 0.02), and serum BGP (r = 0.72, P less than 0.001). Mineral content in the left radius had significant negative correlations with serum BGP levels (r = -0.73, P less than 0.001) and urinary gamma-Gla levels (r = -0.59, P less than 0.01). As these data show, serum BGP and urinary gamma-Gla levels clearly reflect the abnormal bone metabolism and can therefore be useful biochemical markers in PHP.     

Blue Light-Induced Phototropic Response and the Intracellular Photoreceptive Site in Adiantum Protonemata

Blue light-induced phototropism in Adiantum protonemata wasinvestigated with microbeam irradiation. Brief irradiation withblue light effectively induced a phototropic response when itwas applied to a half-side of the apical 200d µm regionof a protonema. The phototropic response was partly reversedby the subsequent far-red light irradiation but the full reversalof the response was not observed even when the fluence of far-redlight was increased. In the far-red reversible part of the response,blue/far-red photoreversibility was repeatedly observed. Thus,both phytochrome and a blue light-absorbing pigment (other thanphytochrome) seem to be involved in the blue light-induced phototropicresponse in Adiantum protonemata. Furthermore, detailed studiesof the far-red light effect on the fluence-response curve forblue lightinduced phototropism revealed that the concomitantmediation by the two receptors was limited to the response inthe relatively higher fluence range of blue light and that theblue light-absorbing pigment alone was responsible in the lowerfluence range. In the higher fluence range, the response mediatedby the blue light-absorbing pigment became saturated and thephytochrome response became evident, indicating a differencein the sensitivities of the two receptor pigments to blue light. When various regions of half-sides of protonemata were irradiatedwith a blue microbeam of 10 µm width, irradiation at theapical 5–25 µm region was most effective both forphytochrome- and blue light-absorbing pigment-mediated response,indicating that the site of blue light perception is almostidentical for each response. (Received July 14, 1986; Accepted September 26, 1986)     

Flavonoid glycosides of the roots of Glycyrrhiza uralensis

The structure of a flavanone glycoside from the roots of Glycyrrhiza uralensis has been confirmed as 4′-O-[β-d-apio-d-furanosyl-(1 → 2)-β-d-glucopyranosyl]liquiritigenin. In addition, two known flavonoid glucosides, ononin (a minor component) and liquiritin (a major component), were isolated from the same extract.