Thrombomodulin is found on endothelium of arteries, veins, capillaries, and lymphatics, and on syncytiotrophoblast of human placenta

We have used antibodies to human thrombomodulin isolated from placenta to investigate the distribution of this cofactor for protein C activation in human tissues. Thrombomodulin was found on endothelial cells of arteries, veins, capillaries, and lymphatics by immunocytochemical staining using an avidin-biotin peroxidase method. Thrombomodulin was not detected on sinusoidal lining cells of liver or on postcapillary high-endothelial venules of lymph node, although the latter contained another endothelial antigen, von Willebrand factor. Other cells noted to contain thrombomodulin antigen are those of the syncytiotrophoblast in placenta. The thrombomodulin in syncytiotrophoblast was primarily on the plasma membrane surface that forms the maternal blood sinus. Syncytiotrophoblast also stained with antibodies to von Willebrand factor, which implies that these cells have multiple endothelial functions. Thrombomodulin antigen was found in all organs studied, with the notable exception of brain.     

Effects of Antimycin, Glucose Deprivation, and Serum on Cultures of Neurons, Astrocytes, and Neuroblastoma Cells

The resistance of cultured mouse neuroblastoma cells, primary cultures of rat cerebellar neurons, and rat brain astrocytes to a block of aerobic metabolism was studied. Parameters such as lactate production and ATP content were measured in the presence of antimycin A and under various conditions of glucose, oxygen, and serum supply. The following conclusions can be drawn: (1) All cell types studied were characterized by an active production of lactate; (2) Incubation of the various cell types in the absence of glucose at normal oxygen tension did not affect ATP levels; (3) Respiration blocked by antimycin led to a Pasteur effect; (4) Neuroblastoma cells, but not the other cell types, were fully resistant to inhibition of respiration provided that sufficient glucose was supplied; (5) In the absence of glucose no stores of energy or utilizable substrate were present in the cell types studied when respiration was blocked; (6) In the presence of fetal calf serum anoxic neurons showed irreversible signs of degeneration.     

Influence of chelation and oxidation state on vanadium bioavailability,and their effects on tissue concentrations of zinc,copper, and iron

Today, vanadium compounds are frequently included in nutritional supplements and are also being developed for therapeutic use in diabetes mellitus. Previously, tissue uptake of vanadium from bis(maltolato)oxovanadium(IV) (BMOV) was shown to be increased compared to its uptake from vanadyl sulfate (VS). Our primary objective was to test the hypothesis that complexation increases vanadium uptake and that this effect is independent of oxidation state. A secondary objective was to compare the effects of vanadium complexation and oxidation state on tissue iron, copper, and zinc. Wistar rats were fed either ammonium metavanadate (AMV), VS, or BMOV (1.2 mM each in the drinking water). Tissue uptake of V following 12 wk of BMOV or AMV was higher than that from VS (p<0.05). BMOV led to decreased tissue Zn and increased bone Fe content. The same three compounds were compared in a cellular model of absorption (Caco-2 cells). Vanadium uptake from VS was higher than that from BMOV or AMV at 10 min, but from BMOV (250 μM only, 60 min), uptake was far greater than from AMV or VS. These results show that neither complexation nor oxidation state alone are adequate predictors of relative absorption, tissue accumulation, or trace element interactions.     

The effect of malathion,diazinon, and various concentrations of zinc,copper, nickel,lead, iron,and mercury on fish

Acute and chronic toxicity tests for malathion, diazinon, copper (Cu), mercury (Hg), lead (Pb), zinc (Zn), nickel (Ni), and iron (Fe) were conducted. Mortalities ofBarilius vagra andCyprinus carpio (common carp) were variable but LC50-96 hr were similar for pesticides. AdultB. vagra seem to be more sensitive to malathion than juvenile carp. Both juvenile carp and adultB. vagra were extremely sensitive to diazinon. Long-term exposure to pesticides modified morphology and behavior. The LC50-96 values for Cu, Hg, and Pb were 0.3, 0.16, and 0.44, respectively, for smaller fish and 1.0, 0.77, and 1.33, respectively, for larger fish. Replicate LC50 values for Zn, Ni, and Fe were somewhat variable, and for these metals, the size of the fish seemed to affect response because LC50 values increased as fish size increased. Cooper, Pb, Zn, and Fe residues following exposure to sublethal concentrations of these metals for 15 d were significantly greater in whole juvenile common carp than in controls.     

Effects of the administration of corticosterone,parathyroid hormone,or both,and of their withdrawal,on rat bone and cartilage histomorphometric parameters,and on osteoprotegerin and RANKL mRNA expression and proteins

We have studied the effects of the treatment with corticosterone (CORT), parathyroid hormone (PTH), or both (CORT + PTH), and of their withdrawal (CORT-rec and CORT + PTH-rec), on the osteoprotegerin (OPG) and receptor activator of nuclear factor-kB ligand (RANKL) localization and expression and on histomorphometric parameters in primary and secondary spongiosa of rat femur and tibia metaphyses. In the secondary spongiosa of the CORT group, the bone remodeling and the OPG/RANKL mRNA ratio decreased. In the PTH group, the bone turnover and the structural and connectivity indices increased, and the OPG/RANKL mRNA ratio fell; this ratio rose, however, in the primary spongiosa. In the CORT + PTH group, remodeling values intermediate between those of the CORT and PTH groups, were detected in the secondary spongiosa, where OPG and RANKL mRNA rose. Return towards control values was found in the recovery groups. The Cartilage Growth Plate Width was reduced in the CORT and CORT + PTH groups and returned to normal values in the recovery groups, while it was not affected by PTH. Independently of treatments, both OPG and RANKL mRNA and proteins were co-localized in the same cartilage and bone cells and in several bone marrow cells. In conclusion, the catabolic effects induced by CORT treatment occur together with an OPG fall and a RANKL rise. In the PTH group in which the bone turnover increase, the OPG and RANKL mRNA expressions differ in the primary and secondary spongiosa, confirming that the bone tissue in these sites can have different metabolic trends.     

Effects of thiazolidinediones on differentiation, proliferation, and apoptosis

Thiazolidinediones induce adipocyte differentiation and thereby limit proliferative potential; hence, early investigations focused on their ability to modulate cellular proliferation and apoptosis. Several lines of evidence indicate significant thiazolidinedione-mediated antitumor activity. An emerging view is that some antitumor effects are totally or partially peroxisome proliferator-activated receptor-gamma (PPARgamma) dependent, whereas others are PPARgamma independent. The aim of this review is to examine the current evidence about the molecular mechanisms by which thiazolidinediones augment cellular differentiation, inhibit cellular proliferation, and induce apoptosis. We first address the role of thiazolidinediones and/or PPARgamma on Wnt/beta-catenin signaling pathway as it affects cellular differentiation and then discuss other pathways that are also involved in differentiation as well as proliferation and apoptosis.     

Studies on the effects of certain salts on germination,on growth of root,and on metabolism

Summary The effects of different concentrations of KCl, K₂SO₄, MgCl₂ and MgSO₄ on the growth in length of the first seminal root of wheat, and on the change in fresh and oven-dry weight of the seedling and its component parts have been studied. The effect of mannitol was also investigated for comparison and to study the osmotic action. The effect of salts on root growth was dependent on salt species; all effects were specific to ions and not due to osmotic activity of solution. The growth of wheat roots was suppressed by concentrations of salts much lower than those required to suppress germination. All solutions of KCl from 0.1 to 50 me/l checked the growth of the root; the retardation increased with increase of concentration. In K₂SO₄ there was a slight activation of root growth for one day in 0.1 and 0.5 me/l; then the growth was suppressed after that. In all other concentrations from 1 to 50 me/l the growth was retarded. In MgCl₂ or MgSO₄ there was some activation of root elongation in 0.05, 0.1 and 0.5 me/l; but higher concentrations retarded root growth.     

Effects of aluminum,manganese, and lime on toxicity symptoms,nutrient composition,and yield of barley grown on a podzol soil

Summary Aluminum toxicity resulted in abnormal root development with many short thick roots and was found at pH 4.3 with or without added Al. The toxicity of Mn was found with no added Mn, and with 50 and 100 ppm added Mn at pH values ranging from 4.0 to 4.7 and appeared as dark spots on the leaves. At pH values ranging from 5.8 to 6.0, no toxicity symptoms were recorded in the absence of added Mn. Al was more detrimental to seedling development than was Mn.No kernels developed at 25 and 50 ppm added Al at pH4.1. Such toxicity was associated with Al contents of 9.6 to 28.5 g/ml of saturated extract of soil. The highest kernel yields were recorded at pH 5.8 to 6.0 and were associated with 116 to 296 ppm Mn in tissue and of less than 0.1 g/ml of Al in the saturated extract. Increased rates of Mn and Al resulted in increased concentrations of Ca, Mg, and K in the saturated extract of soil. The results indicated that Al toxicity can be eliminated by liming to soil pH values of greater than 5.5; however, Mn toxicity may occur at pH values as high as 5.8 in the presence of large quantities of Mn.Contribution no. 274, Research Branch, Research Station, P. O. Box 1210, Charlottetown, P. E. I.     

The Influence of Shoots, Roots, and Hormones on the Distribution of Leucine, Phosphate, and Benzyladenine

The problem studied was the control of the relative distributionof metabolites to the shoots and roots. The movement of radioactivityapplied as leucine, phosphate, or benzyladenine (BA) was followedin small regenerated bean plants in which the distribution ofradioactive sucrose had been previously studied. Removal ofeither the shoots or the roots greatly reduced the transportof radioactivity in their direction. Auxin and BA partiallyreplaced the growing regions, but their effects were in no wayspecific to the parts of the plant in which they are naturallyformed. Radioactivity from BA, in contrast to the other substanceswhich were studied, moved preferentially towards the shootsand not the roots. The results indicate that the relations betweengrowing shoot and roots involve a direct hormonal interaction.The sinks which develop in response to the hormones may havesome specificity in terms of the substances they require orproduce and whose transport they influence.     

Influence of culinary treatment on the concentration and on the bioavailability of cadmium,chromium, copper,and lead in seafood

BackgroundSeafood present important advantages for human nutrition, but it can also accumulate high levels of toxic and potentially toxic elements. Culinary treatments could influence seafood chemical element content and element bioavailability. In this study, the influence of culinary treatments on the total concentration and on the bioavailability of Cd, Cr, Cu and Pb in shark, shrimp, squid, oyster, and scallop was assessed.MethodsBoiling, frying, and sautéing with or without seasonings (salt, lemon juice and garlic) were evaluated. Total concentration and bioavailability of Cd, Cr, Cu and Pb in seafood after all these culinary treatments were compared with those in uncooked samples. Analytes were determined by triple-quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). An alternative to express the results avoiding underestimated or overestimated values was proposed.ResultsThe analytes concentration in seafood without culinary treatment varied from 0.0030 μg g⁻¹ (shrimp) to 0.338 μg g⁻¹ (oyster) for Cd; 0.010 μg g⁻¹ (squid) to 0.036 μg g⁻¹ (oyster) for Cr; 0.088 μg g⁻¹ (scallop) to 8.63 μg g⁻¹ (oyster) for Cu, and < 0.005 μg g⁻¹ (shrimp, squid and oyster) to 0.020 μg g⁻¹ (shark) for Pb. Only Cd (in scallop) was influenced by culinary treatments (reduction from 37 to 53 % after boiling, frying, and sautéing). Bioavailability percentage varied from 11% (oyster) for Cd; 18% (oyster) to 41% (shark) for Cr; 6% (shark) for Cu, and 8% (oyster) for Pb. Bioavailability percentage was not influenced by culinary treatments.ConclusionCadmium concentration was reduced in scallop after some culinary treatments (reduction o 37-53% after boiling, frying, and sautéing), but bioavailability percentage was not influenced. The employed analytical method was adequate for the purpose, presenting import results for food safety assessment about the influence of culinary treatments on metals concentration and bioavailability in seafood.     

Update on the effects of vitamins A, C, and E and selenium on carcinogenesis

The effects of vitamins A, C, and E and of selenium on carcinogenesis are briefly summarized and updated. These vitamins and minerals were selected because they have been studied extensively in recent years with a variety of carcinogenesis models. The consumption of vitamin A and its precursors (carotenoids) has been negatively correlated with cancer at a number of sites, particularly the lung. Animal investigations on vitamin A involvement in carcinogenesis have generally been of three types: those assessing the effect of vitamin A deficiency, the effect of excess vitamin A, or the effect of supplementation with synthetic analogs of vitamin A. Vitamin A deficiency had no effect on salivary gland carcinogenesis, enhanced urinary bladder, lung, and liver carcinogenesis, and inhibited colon carcinogenesis. Excess of various forms of vitamin A enhanced or inhibited skin tumorigenesis, inhibited mammary carcinogenesis in rats (but not in mice), and carcinogenesis of the forestomach, liver, and urinary bladder (with one model, but not with another), or enhanced or did not influence lung carcinogenesis. Vitamin A analogs have enhanced or inhibited skin tumorigenesis, inhibited salivary gland, mammary, and urinary bladder carcinogenesis, enhanced tracheal and liver carcinogenesis, and either enhanced or inhibited pancreas carcinogenesis, depending upon the model employed. Although retinoids have been shown to inhibit carcinogenesis at many sites, numerous negative studies have been reported and some reports have indicated enhanced carcinogenesis. The most convincing evidence for the involvement of vitamin C in cancer prevention is the ability of ascorbic acid to prevent formation of nitrosamine and of other N-nitroso compounds. In addition vitamin C supplementation was shown to inhibit skin, nose, tracheal, lung, and kidney carcinogenesis, to either not influence or enhance skin, mammary gland, and colon carcinogenesis, and to enhance urinary bladder carcinogenesis, when given as sodium ascorbate, but not when given as ascorbic acid. Like vitamin C, vitamin E can inhibit nitrosation. Vitamin E was shown to inhibit skin, cheek pouch, and forestomach carcinogenesis, to enhance or inhibit colon carcinogenesis, and to have no effect on or to inhibit mammary gland carcinogenesis, depending upon the method of vitamin E administration or the level of dietary selenium or dietary fat. Selenium effects on carcinogenesis have been recently reviewed and the present discussion only updates this area by indicating that enhancement of carcinogenesis by dietary selenium supplements has been observed in the liver, pancreas, and skin.(ABSTRACT TRUNCATED AT 400 WORDS)     

Effects of berberine,glaucine, stephaglabrine,and sanguirythrine on neuromuscular transmission

The effects of certain alkaloid (glaucine, stephaglabrine, and sanguirythrine) on parameters of neuromuscular transmission follow a complex pattern and are thought likely to operate via two or more different mechanisms. These alkaloids, in common with berberine, reduced the amplitude of miniature potentials at the frog neuromuscular junction. All four concentrations reduced and raised miniature potential rate at low and high concentrations respectively — a very marked action in the case of sanguirythrine, producing virtually a 100-fold increase, probably due to its uncoupling effect on oxidative phosphorylation at the mitochondria of the nerve endings. Sanguirythrine and stephaglabrine both gave rise to repeated muscular contraction which matches their anticholinesterase activity. High glaucine concentrations also induced contraction of the muscles.Institute for Hydrobiontic Substance Research, Soviet Ministry of Health, Moscow. Translated from Neirofiziologiya, Vol. 23, No. 2, pp. 131–135, March–April, 1991.