International journal of tissue reactions最新文献

Our understanding of the in vivo metabolic functions of apoA-I and A-II has greatly advanced with the use of transgenic mice, but the physiological role of apoA-IV remains elusive. Both apoA-I and A-II are necessary for the structural stability of high-density lipoprotein (HDL). Structural differences exist between human and mouse A apoproteins because: i) human cholesterol ester transfer protein, lecithin cholesterol acyl transferase and phospholipid transfer protein interact better with human apoA-I; ii) human apoA-I and A-II, alone or in combination, form polydisperse instead of monodisperse HDL particles. Human apoA-II overexpression has highlighted its inhibitory effect on lipoprotein lipase and hepatic lipase, resulting in hypertriglyceridemia and concomitantly decreased HDL and apoA-I. After long-term challenge with an atherogenic diet, mice are less protected against lesion formation by human apoA-II, mouse apoA-II being overtly proatherogenic. On the other hand, human apoA-I confers great protection against lesion formation and causes reduction of preexisting lesions. Human apoA-IV is also protective, although the mechanisms by which this protection is achieved remain to be determined.

Cell and tissue lipoperoxidation of the kidney induced by cyclosporine through the release of reactive oxygen species has recently been pointed out to be one of the factors responsible for the toxic phenomena related to the administration of cyclosporine. Our previous research on propionyl carnitine had shown an antilipoperoxidative effect of this substance on isolated cells such as erythrocytes and leukocytes, and also on the endothelial, vasal and cardiac tissues. In the experiments presented herein we also examined if propionyl carnitine could carry out its already well-known antilipoperoxidative effect in the renal tissue, and if this mechanism could be taken into consideration in order to explain the protective effect of propionyl carnitine against cyclosporine induced toxicity. Trials were carried out on isolated and perfused rat kidneys, and we were able to observe that propionyl carnitine exerted a protective action on toxic lipid peroxidation phenomena induced by cyclosporine. The results we obtained, together with other mechanisms which we had already proved regarding the intense protective activity of propionyl carnitine on cyclosporine-induced nephrotoxicity, complete the complex picture that describes the protective activity of propionyl carnitine against cyclosporine toxicity.

The aim of this study was to assess the efficacy and tolerance of propinox administered i.v., and establish a dose-response relation according to three dose levels (10, 20 and 30 mg), vs. placebo in patients with moderate to severe acute biliary pain. Three hundred and fifty patients were included: 85 received placebo treatment, 81 were treated with propinox 10 mg, 91 with propinox 20 mg and 93 received propinox 30 mg. Spontaneous pain intensity was assessed according to a visual analog and a verbal scale before treatment and 20, 60 and 120 min after. All treatments induced significant and progressive pain reduction at all controls, but patients treated with 20 and 30 mg of propinox showed significantly lower pain intensity after 120 min compared to the placebo group. The last control revealed that 28% of patients receiving placebo had no pain while 60% of patients treated with propinox 30 mg reported absence of pain with a statistically significant difference (p < 0.001). All treatments were very well tolerated and there were no dropouts due to adverse events. Mouth dryness was the adverse effect occurring with a significantly higher frequency than that observed with placebo although it was only seen in patients treated with 20 mg and 30 mg active doses. The results of this study showed that propinox was an effective drug in the treatment of moderate to severe colic pain of biliary origin. Concerning efficacy and side effects, a clear dose-response relation was observed; the 20 mg and 30 mg doses being significantly superior to placebo.

An 8-week, randomized, double-blind study comparing the efficacy and tolerability of policosanol and acipimox was conducted in patients with type II hypercholesterolemia. Prior to entry into active treatment, all patients followed a standard cholesterol-lowering diet for 12 weeks. Sixty-three patients were randomized to receive either policosanol (10 mg/day) or acipimox (750 mg/day) tablets for 8 weeks under double-blind conditions. Both groups were similar at randomization. Policosanol significantly reduced total cholesterol (p < 0.0001) (15.8%), low-density lipoprotein (LDL)-cholesterol (21%) and the ratios of LDL-cholesterol to high-density lipoprotein (HDL)-cholesterol (15.8%) and cholesterol to HDL-cholesterol (11.5%). Acipimox significantly lowered both cholesterol and LDL cholesterol by 7.5%. The percent changes of total cholesterol, LDL-cholesterol and both ratios were larger in the policosanol group than in the acipimox group. Both drugs were well tolerated. Acipimox significantly increased (p > 0.001) aspartate amino transferase levels but only four patients showed increases above the normal limit. Policosanol significantly reduced creatinine values (p > 0.05) but no patients had values out of the normal range. Four patients withdrew from the study (two from each group) but none withdrew because of adverse effects. No adverse effects were reported in the policosanol group, while five patients on acipimox reported adverse effects (hot flushes, nausea, vomiting, headache, hypochondrial pain and leg edema). These results indicate that policosanol (10 mg/day) was more effective and well tolerated than was acipimox (750 mg/day) in this study population.

Recent knowledge of the pathophysiology of rheumatoid arthritis and the mechanism of drug effects have enabled the use of new drugs and drug combinations in rheumatoid arthritis therapy. This study investigates the efficacy of both enzyme therapy and combined therapy with cyclosporin in rats with adjuvant arthritis. Rats with adjuvant-induced arthritis were administered either cyclosporin A (2.5 or 5.0 mg/kg/day per os), a mixture of enzymes (Phlogenzym (PHL); 45 mg/kg twice daily intrarectally), or a combination of 2.5 mg cyclosporin A and 90 mg PHL for a period of 40 days from the adjuvant application. Levels of serum albumin, changes in hind paw swelling and bone erosions were measured in rats as variables of inflammation and arthritis-associated destructive changes. Treatment with 5 mg of cyclosporin A, as well as with the combination therapy with cyclosporin A plus PHL, significantly inhibited both the inflammation and destructive arthritis-associated changes. However, 2.5 mg of cyclosporin A and PHL alone inhibited these disease markers, although to a lesser extent and at a later stage of arthritis development. The results show the inhibitory effect of enzyme therapy on rat adjuvant arthritis, as well as the efficacy of a low dose of cyclosporin A given in combination with enzyme therapy, which may be useful in the treatment of rheumatoid arthritis.

Trans-resveratrol, a natural stilbene present in wine and grapes, has been studied mainly for its antiinflammatory and anticancer activities. In this study the activity of resveratrol on proliferative immunological parameters (differentiation, apoptosis, phagocytosis and intracellular killing) was studied using a U937 human promonocytic cell line in comparison with another polyphenol, quercetin. After incubation of the pathogen, Candida albicans, intracellular killing by macrophage-like cells was decreased by quercetin and resveratrol 10 microM but was enhanced by resveratrol 1 microM after 20 h of treatment. Phagocytosis rate, expressed as phagocytosis frequency, (i.e., percentage number of phagocytosing cells/total cells) at 20 h was highest with resveratrol 10 microM and was higher with quercetin 10 microM than with resveratrol 1 microM. The phagocytosis index exhibited the same trend. While both polyphenols demonstrated cytostatic activity on U937 growth, a prointraphagocytic effect for resveratrol 10 microM-treated cells at 10 min, resveratrol 1 microM-treated cells at 20 h and resveratrol 10 microM-treated cells at 48 h was observed. Morphological examination with optic microscopy demonstrated both apoptotic and differentiating cells, even after 10 min treatment. Resveratrol-induced apoptosis (following 4 h treatment) was confirmed by flow cytometry at concentrations as low as 1 microM and 100 nM in the assay for detection of membrane phosphatidylserine. Resveratrol- or quercetin-treated, but unstimulated cells, did not produce tumor necrosis factor-alpha protein. As phosphatidylserine externalization triggers specific recognition by monocytes and macrophages, removal of intact apoptotic cells is important a) in cell population selection and differentiation for antiblastic therapy, and b) in preventing the release of toxic inflammatory substances such as reactive oxygen substances and proteolytic enzymes by dying cells. This observation suggests that wine polyphenols, at the same concentrations as those found in plasma after moderate wine consumption, are important cofactors in antiinfective, antiinflammatory and anticancer nonspecific immune reactions.

We investigated the in vitro effect of domperidone-induced hyperprolactinemia on plasma cytokine concentration and blood leukocyte cytokine production in healthy female volunteers. No changes were found in the plasma concentration of interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interleukin (IL)-4, IL-10, IL-6 and IL-13 during hyperprolactinemia when compared with control values. Using unseparated blood leukocytes, we found that the spontaneous production of IL-6 (4-8 h) and transforming growth factor (TGF)-beta 1 (2-4 h) was significantly decreased and that the in vitro stimulated production of IFN-gamma (2-8 h) and TNF (4 h) was significantly increased compared with control. Our data concerning the increased IFN-gamma and TNF producing capacity of unseparated leukocytes during pharmacologically induced hyperprolactinemia strongly support the possibility that the lymphocyte production of these cytokines can be rapidly amplified by prolactin via a priming mechanism.

Colony stimulating factors (CSFs) are now widely used in cancer treatment and immunological disease therapy. Both granulocyte CSF (G-CSF) and granulocyte-macrophage CSF (GM-CSF) are used to increase neutrophil counts in Felty syndrome. In the present study, the effects of macrophage CSF (M-CSF), G-CSF, GM-CSF and interleukin-3 (IL-3) (10 ng/ml) on the production of nitric oxide and prostaglandin E2 (PGE2) by cartilage explants were examined over 24 and 48 h. The effects of these CSFs were also measured in combination with IL-1 beta (10 ng/ml). M-CSF, GM-CSF and IL-3 had no effect on nitrite production. However, both IL-1 beta and G-CSF caused a significant increase (p < 0.05) in nitrite levels at 48 h. NG-L-arginine-methyl-ester was used to inhibit nitrite production induced by G-CSF and this implicated nitric oxide synthase activity. When G-CSF and IL-1 beta were used in a combined treatment, nitrite levels were significantly increased (p < 0.05) at both 24 and 48 h. Both IL-3 alone and in combination with IL-1 beta caused elevated PGE2 production in this model. PGE2 levels were also significantly increased by stimulation with GM-CSF and IL-3 combined with IL-1 beta. These findings demonstrate that GM-CSF, G-CSF and IL-3 may induce changes in the production of inflammatory mediators such nitric oxide and PGE2 in cartilage chondrocytes. Hence, CSFs may play a vital role in influencing cartilage metabolism in rheumatoid and osteoarthritis.

The main purpose of this study was to investigate the possible protective effect of a single dose of glucocorticoid dexamethasone administered just before reperfusion on the viability of cold-stored inferior epigastric rat skin flaps. We also sought evidence for the antiinflammatory mechanism of action of dexamethasone involved in this model of cold ischemia-reperfusion. The viability of flaps on reperfusion day 7, after 1, 2, 3, 4, or 5 days of cold ischemia, was 80, 74, 60, 47 and 12% respectively. Four days' cold ischemia time was chosen to test the effect of intraperitoneal dexamethasone administration (2.5 mg/kg) 30 min prior to reperfusion. Flap survival after 4 days' cold ischemia/7 days' reperfusion increased significantly from a mean of 37.0% survival in saline-treated controls to 73.3% in dexamethasone-treated rats (p < 0.05). Dexamethasone treatment also resulted in significantly lower skin flap water content (a measure of edema) and myeloperoxidase activity (an indicator of neutrophil infiltration) but had no significant effect on skin levels of hydroperoxides (a measure of free radical activity). In conclusion, dexamethasone attenuates ischemia-reperfusion injury in cold-stored skin flaps by reducing the tissue levels of several proinflammatory mediators.

Serum calcitriol levels decrease with advancing age in relation to reduced dietary intake or poor intestinal absorption of vitamin D. These decreased levels affect the development of senile osteopenia, which can be effectively prevented by the administration of alendronate and calcium. To evaluate the effect of a combined treatment with alendronate and calcitriol on bone mineral density (BMD), we followed 152 osteopenic postmenopausal women, aged 55-75 years, for 9 months. They were divided into three groups. The first group was treated every other day with 0.25 microgram of synthetic 1,25-dihydroxyvitamin D3 plus 10 mg alendronate. The second group received the same dose of alendronate plus calcium (500 mg/day). The third group received only calcium (500 mg/day). BMD measurements were made at the level of the lumbar spine and the femoral neck. At the beginning and at the end of the period of treatment the same biochemical analyses of bone metabolism were made. There were no significant differences in the baseline values of the three groups in the biological parameters. Alendronate plus calcium treatment led to a significant reduction in total alkaline phosphatase and hydroxy prolinuria as well as to a significant increase in lumbar and femoral bone density. The same changes were observed in the group treated with alendronate plus calcitriol except that femoral BMD did not significantly improve. These results show that continuous treatment for 9 months with calcitriol or calcium in combination with alendronate significantly increases both vertebral and femoral neck density (from 3.8% to 4.5% and from 0.61% to 2.36% respectively) in osteopenic postmenopausal women. The effects of both combinations on bone mass are clearly greater than those achieved by calcium monotherapy.