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Micronutrient antioxidant status in patients with primary Raynaud's phenomenon and systemic sclerosis.

OBJECTIVE: To investigate the possibility that micronutrient antioxidant status is an important factor in determining the severity of Raynaud's phenomenon (RP) and in differentiating between patients with primary Raynaud's phenomenon (PRP) and those in whom Raynaud's is secondary to systemic sclerosis (SSc). METHODS: Four micronutrient antioxidants (selenium, vitamin E, beta-carotene and ascorbic acid) and 2 "markers" of free radical associated activity were assayed in peripheral blood from 10 patients with PRP, 9 with limited cutaneous SSc (ISSc), 9 with diffuse SSc (dSSc) and 15 healthy control subjects. RESULTS: Plasma ascorbic acid was reduced in all 3 groups of patients: median level 10.6 mg/l in controls, 4.8 mg/l in PRP (p < 0.01), 2.5 mg/l in ISSc (p < 0.01) and 6.8 mg/l in dSSc (p < 0.05). A reduction in serum selenium was especially found in dSSc (median 75 micrograms/l compared to 100 micrograms/l in controls, p < 0.05). In keeping with these deficiencies, the serum concentration of 9, 11, linoleic acid was elevated in RP patients: median values for the molar ratio of the isomer to the parent fatty acid were 1.91% in controls, 3.70% in ISSc (p < 0.05) and 3.85% in dSSc (p < 0.01). Smoking patients showed lower levels of ascorbic acid and higher levels of the linoleic isomer than nonsmokers. CONCLUSION: Deficiencies of ascorbic acid and selenium may predispose towards irreversible tissue injury in RP patients and cigarette smoke may be an independent risk factor. Micronutrient antioxidant supplements may be of therapeutic value.

Aging↗

The role of ascorbic acid in carcinogenesis.

Vitamin C is an essential nutrient whose protective role in carcinogenesis has been discussed for more than 50 years. Epidemiologic studies suggest that the consumption of vitamin C-rich foods is associated with a lower risk of cancers of the esophagus and stomach. The observation that cancer patients have low leukocyte vitamin C levels led to therapeutic trials the results of which are controversial; the hypothesis that vitamin C acts like a drug must be questioned. On the other hand, ascorbic acid interacts with various tumor-inducing compounds, such as the precursors of N-nitroso compounds, to prevent the formation of tumors. Experiments with animals and cell cultures indicate that ascorbic acid can interfere with the metabolism of tumor promoters. It has also been postulated that ascorbic acid helps to prevent cancer by enhancing cellular immunity. In general, evidence suggests that vitamin C can inhibit the formation of some carcinogens.

Animals↗

Histochemical and enzymehistochemical alterations during experimental cardiomyopathy.

Investigation of ethiology, pathogenesis, morphogenesis, pathokinesis, treatment and prevention of cardiomyopathy is one of the most important problems of cardiology. Last years many scientific forums have been devoted to cardiomyopathy problems and still many issues remain disputable and needs further investigation and definition. In particular, investigation of metabolic processes in cardiac muscle seems of great importance. Obtained data will promote elaboration of adequate means toward the correction of cardiac decompensation during cardiomyopathy. The main goal of present study was the investigation of oxidation-reduction and electron transport associated protein activity in myocardium during experimental cardiomyopathy. Experiments were carried out on 30 male rats (180 - 200 g weight). Based on histological, histochemical, enzymehistological investigations conclusion has been made that during experimental autoimmune cardiomyopathy activity of oxidation-reduction and electron transport enzymes is sharply decreased along with the decrease of ascorbic acid and tiny granule glycogen amount (with altered topographic distribution) determining energy deficiency and weakening of cardiac muscle contractile function. It is possible to consider that the present study will open the way for future research and prompt us to select optimal therapeutic agents.

Animals↗

Treatment options in extravasation injury: an experimental study in rats.

Local skin necrosis after extravasation of doxorubicin hydrochloride (Adriamycin), a widely used chemotherapeutic agent, is a common problem in cancer patients. Even though several treatment options have been proposed for extravasation injury, there is still controversy regarding the management of such lesions. The aim of this study was to compare the efficacy of saline infiltration, vitamin C infiltration, suction technique, and early surgical excision as a treatment in a rat extravasation model. The authors planned their study in two stages. In stage 1, the lowest effective dose of doxorubicin at which a homogeneous skin necrosis was formed and the method of administration were investigated. Intradermal and subpannicular injections were made for six rats, using six different concentrations of doxorubicin (0.33, 0.5, 0.66, 1.0, 1.33, and 1.5 mg/ml). In stage 1, the intradermal injection produced homogeneous and uniform tissue necrosis. In stage 2, the efficacy of saline infiltration (group 1), vitamin C infiltration (group 2), suction (group 3), suction and saline washout (group 4), suction and vitamin C washout (group 5), and early surgical excision (group 6) was compared. The treatment options were applied 2 hours after doxorubicin injection. At the end of the seventh day, the presence and size of ulcers at the injection site were calculated. Fourteen days after injection, a histopathologic examination was performed for each treatment and control group. In groups 1 and 3, there was no statistically significant difference in the size of necrosis compared with the control groups. In groups 2, 4, and 5, the size of necrosis was smaller compared with the control groups, and this was statistically significant. Furthermore, in group 4 (suction and saline washout) and group 5 (suction and vitamin C washout), the calculated area of necrosis was smaller compared with other treatment groups, and this was statistically significant. The findings supported the assertion that suction and saline or vitamin C washout reduce necrotic tissue size in extravasation injury.

Animals↗

[Efficiency treatment of new cases of destructive pulmonary tuberculosis in the presence of concurrent iron deficiency anemia].

A hundred and twenty nine new cases of destructive pulmonary tuberculosis were examined. Of them, 95 patients were diagnosed as having first-degree iron deficiency anemia. Anemia was found to have a negative impact on the clinical efficiency of therapeutical measures. For correction of anemia, the use of antioxidants (tocopherol acetate, ascorbic acid) and an antihypoxant (riboxine) yielded better clinical results than did an iron-containing agent (ferroplex). These results were mostly close to those obtained in a group of patients without anemia.

Adult↗

alpha-Tocopherol and ascorbic acid prevent memory deficits provoked by chronic hyperprolinemia in rats.

In the present study we investigated the action of alpha-tocopherol and ascorbic acid on the effects elicited by chronic hyperprolinemia on rat performance in the Morris water maze. Rats received subcutaneous injections of proline (experimental group) twice a day, with 10 h-interval, from the 6 to 28th days of age or an equivalent volume of 0.9% saline solution (controls). Half of the proline-treated group also received intraperitoneal administration of alpha-tocopherol (40 mg/kg) and of ascorbic acid (100 mg/kg) from the 6 to 28th days of life. On the 60th day of life, rats were subjected to testing in the water maze. Results show that chronic proline administration provokes impairment on spatial learning in reference memory task, as revealed by the increase of latency in acquisition, in the probe trial and in crossing over the platform location, as well as by the number of crossings, when compared to saline-treated animals. Proline-treated rats also demonstrated a reduced efficiency to find the platform position in the working memory task. Rats chronically treated with proline plus alpha-tocopherol and ascorbic acid had above effects prevented, suggesting the participation of oxidative stress in such effects. Our findings lend support to a novel therapeutic strategy, based on these vitamins, to the cognitive dysfunction associated with hyperprolinemia type II.

Animals↗

The use of antioxidant therapies during chemotherapy.

OBJECTIVE: At the present time, many cancer patients combine some form of complementary and alternative medicine therapies with their conventional therapies. The most common choice of these therapies is the use of antioxidants. RESULTS: A review of four common antioxidants is undertaken, which includes vitamin E (mixed tocopherols and tocotrienols), beta-carotene (natural mixed carotenoids), vitamin C (ascorbic acid), and vitamin A (retinoic acid). Antioxidants act as electron acceptors as well as therapeutic biologic response modifiers. Despite the fact that chemotherapy-induced formation of free radicals is well-demonstrated, chemotherapy-induced cytotoxicity in general does not seem to depend on formation of reactive oxygen species. CONCLUSIONS: Currently, evidence is growing that antioxidants may provide some benefit when combined with certain types of chemotherapy. Because of the potential for positive benefits, a randomized controlled trial evaluating the safety and efficacy of adding antioxidants to chemotherapy in newly diagnosed ovarian cancer is underway at the University of Kansas Medical Center.

Antineoplastic Agents↗

[The effect of selected drugs on the interpretation of hemostasis- related study results].

By applying in vitro and additional in vivo investigations of analysing coagulation in human beings with the routine methods TPZW, PTT and TZ it was possible to exclude influences of hemostasis described in literature and often uncritically generalised in papers and articles as well as assumed influences for such medicaments as acetylsalicylic acid, ascorbic acid, chlorpromazine, fluphenazine, gentamycin, haloperidol, lincomycin, methyldopa, sodium fluoride and penicillin G in therapeutic doses or concentrations in vitro respectively which correspond to therapeutic or toxic doses. For such solutions of infusion as infucoll 6% and gelafusal there exist these influences in the sense of an acceleration of coagulation in vitro. They can be regarded as shiftings within the normal range of methods which have no clinical relevance. Infucoll M 40 will to a concentration of 0.25 mmol/l of blood which corresponds to therapeutic conditions, to a shortening of Tz falling below the normal range of the method. These findings correlate with data in literature and could be identified even in lower concentrations by excluding the effect of dilution. According to literature these relations are identical with those in vivo some minutes after infusion.

Adult↗

[Effect of therapy with beta-adrenoblockers and vitamin complexes on indices of oxyproline excretion in various hereditary connective tissue diseases].

Excretion of hydroxyproline with urine was studied in 16 children (5-14 years old) with Marphan-Like syndrome and Marphan, Ehlers-Dunlos and Larson syndromes after therapy involving propranolol and a complex of vitamins (ascorbic acid, riboflavin and pyridoxine) and recommended on the basis of echocardiographic analyses. The therapeutic course appears to cause quantitative and qualitative correction of collagen and apparently of elastin fibrilles development. Depending on initial patterns of hydroxyproline excretion and the syndrome form the correction could be complete or partial, while positive effect of the treatment was stable or provisional. The data obtained suggest that the complex treatment developed might be applied as a preoperative therapy of the patients with Marphan-like syndrome as well as with syndromes of Marphan and Ehlers-Dunlos before thoracoplastics caused by hereditary chest deformation and by impairments of cardiovascular system.

Adolescent↗

Free radical scavenging properties of apomorphine enantiomers and dopamine: possible implication in their mechanism of action in parkinsonism.

The influence of R(-) apomorphine, S(+) apomorphine and dopamine on the oxidation kinetics of two polyunsaturated fatty acids (PUFA) (cholesteryl linoleate (CL) and Trilinolein (TL)) was investigated. The oxidation was initiated by free radicals generated through thermal decomposition of 2.2'-Azobis(2-methyl-propionitrile) (AMPN) in phosphate buffer (pH 7.4) thermostated at 50 degrees C. The hydroperoxides formed were determined by iodine titration using a diode array spectrophotometer at 290nm. Both enantiomers of apomorphine as well as dopamine exerted an inhibitory effect. Tocopherol (alpha-tocopherol) and ascorbic acid were used as controls. The former inhibited while ascorbic acid facilitated the oxidation reaction. These results are discussed in relation with the possible role of oxidative injury in parkinsonism and the usefulness of apomorphine in elevating "on-off" episodes. On this basis, the non-dopaminergic enantiomer of apomorphine (S(+)-isomer) is put foward to test the importance of its radical scavenging properties in parkinsonism which could eventually lead to a therapeutic alternative with less side effects.

Apomorphine↗