NO , protective effects

Several studies have investigated the role of dietary factors in prostate cancer risk, but results appear inconsistent. Significant effects have not been detected for dietary soya products certain vegetables, beans, fruit, rice and seaweed appear to be protective in some studies, while another has shown no protective effect from seaweed or vegetable consumption. In addition, a number of other risk factors have been shown to be associated with an increased risk of this cancer, including meat and dairy products and carotenoids. 

Letrozole 2.5 mg once daily 15% Headache, nausea, dyspepsia, skin rash 1. No protective effect on bone recommend calcium supplementation. 

The part of the study involving hysterectomized women was also interrupted in February 2004 after nearly 7 years of treatment because there was no protective effect on the risk of heart disease, but the risk of stroke increased at the same rate as for the estrogen plus progestin combination. 

Arterial endothelial injury. Environmental smoke, administered to ovariectomized rats treated with subcutaneous placebo or 17 p-estradiol pellets for 6 weeks, produced a more than fourfold increase of carotid artery low-density lipoprotein (LDL) accumulation compared with filtered air exposure. The effect was largely mediated by increased permeability. No protective effect of estradiol was observed. Acute smoke exposure of a buffer solution containing LDL produced a more than sixfold increase in the highly reactive carbonyl glyoxal. Perfusion of this solution through carotid arteries produced 105% increase in permeability. Perfusion of glyoxal alone produced a 50% increase in carotid artery permeability ... 

Bilobalide, a main constituent of the terpene fraction of the EGb, possesses anticonvulsant activity against convulsions induced by pentylenetetrazol, isoniazid, 4-0-methylpyridoxine, and electroshock. Reduced durations of convulsions and prolonged onset time of convulsions induced by chemical convulsants and electroshock were observed in mice treated orally with bilobalide (30 mg/kg/day, for 4 days). However, bilobalide has no protective effect against bicuculline- and strychnine-induced convulsions [99,100]. 

Lopez-Lopez G, Moreno L, Cogolludo A, Galisteo M, Ibarra M, Duarte J, Tamargo J. 2004. NO scavenging and NO protecting effects of quercetin and their biological significance in vascular smooth muscle. Mol Pharmacol 65 851-859. 

In a recent study, Retegan compared the radiolytic stability of C5-BTBP and CyMe4-BTBP in hexanol or in cyclohexanone (242). No protective effect of a cyclic diluent was observed on europium extraction, whereas surprising results were obtained with americium. The behavior needs to be more precisely defined. 

The mean time to death (LTso) values were prolonged in mice that were pretreated with vitamin E, Vitamin A, and/or glucose 30 minutes before dosing with DNOC (Tesic et al. 1972). In addition, thiamazole increased the LTso value by a factor of 2.72, while chlorpromazine had a greater influence on LTso values and was more protective than thiamazole in DNOC treated mice. Doses of 8 and 12 mg/kg chlorpromazine were more protective than doses <6 mg/kg, which had no protective effect. The authors proposed that larger doses of chlorpromazine may cause a significant reduction in oxidative processes and decrease in body temperature, while the protective effect of thiamazole may be associated with its ability to decrease basal metabolic rate. 

Acetazolamide has been given during surgery to prevent lOP elevations after pars plana vitrectomy with fluid-gas exchange. No protective effect was demonstrated on lOP 4 to 8 hours after surgery or on the first postoperative day. 

If no protective effect is found, check if protection is provided under less severe agitation and/or aeration conditions. 

This is shown by the facts that the aldehyde-hydrogen ratio is only 35.7 per cent and the gas composition shows 60 per cent hydrogen, 20 per cent carbon monoxide, and 15-17 per cent methane. The presence of 8 per cent water in the ethanol apparently has no protective effect on the aldehyde as it does in the presence of copper catalysts." Because of this undesirable activity in promoting aldehyde decomposition, nickel catalysts are not applicable to the dehydrogenation of ethanol or alcohols in general. 

Recent results of Schnabel [370] do not, however, confirm this view. Copolymers of dimethylsiloxane and phenylmethylsiloxane and copolymers of dimethylsiloxane and diphenylsiloxane of various compositions have been irradiated with 7-rays. Values of GCL were determined for both types of copolymers. With equal concentrations of phenyl groups, the second polysiloxane is less radiation stable than the first, but for both types, the value of Gc L depends linearly on the electron fraction of the dimethylsiloxane units. No protective effect of the phenyl group, in fact, exists. 

In summary, oxysterols are known to exist in atherosclerotic lesions and have been demonstrated in cell-culture experiments to have profound cellular effects that could influence the development, progression, and reversal of atherosclerosis. The key question in this field of research, however, is whether the concentrations of oxysterols in vivo are high enough to influence atherogenesis. Thus far, only the oxysterol-activated nuclear transcription pathway has been directly supported by in vivo data, and even in this case the precise roles and identification of the activating oxysterols in vivo have not yet been elucidated. Moreover, to the extent that oxysterols are generated in vivo and not just obtained from the diet, their role in human atherosclerosis has been questioned by clinical trials showing little or no protective effect of antioxidants on atherosclerotic coronary artery disease (K.J. Williams and E.A. Fisher, 2005). 

Another way to protect ascorbic acid from oxidation consists of the chelating mechanism. As has been discussed above, flavonoids with ortho-phenol structure have the ability to chelate bivalent metals, which may undergo the oxidation of ascorbic acid, and this mechanism of protection for anthocyanins is being proposed by Sarma et al [167], These former reports might explain what was proposed by Rusznyak and Szent-Gyorgyi more than six decades ago when they observed that the administration of lemon juice decreased the fragility and permeability of the capillary wall, where ascorbic acid alone had no protective effect, and led them to propose flavonoids as vitamin P. 

Weak NO production can induce or protect from apoptosis, this phenomenom is very dependent of target cell. Roughly carcinoma cells and normal macrophages or lymphocytes would be NO sensitive whereas leukemic cells and endothelial cells would be NO resistant. NO induced apoptosis could involve p53 accumulation, mitochondrial dysfunctions and cytochrome c release, with or without caspase activation and Bcl-2 inhibition. The NO protective effect could be due to inhibition of caspase activity by nitrosylation with or without Bcl-2 activation. 

Retrospective studies suggested that estrogens had beneficial effects on cognition and delayed the onset of Alzheimer s disease. However, in randomized trials, no protective effect was observed, and the incidence of dementia in the treated group was actually increased. 

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