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M Nechifor

Publications and source records attributed to M Nechifor.

At least 37 records · Page 2Linked to original sources
PubMedDate not supplied

[Experimental data on epithelial factors modulating bronchial reactivity].

A tracheobronchial smooth muscle reactivity study on isolated guinea pig tracheal rings was done. The presence of two different factors active on smooth muscle, an inhibiting one, as well as an activating one was identified. Generated on different pathways, the epithelial derived relaxing factor is a cyclooxygenase dependent prostaglandin, while the activating epithelial factor seems to be a thromboxane derivate.

Animals↗
PubMedDate not supplied

[Pharmacological studies of sulbactam and its association with semisynthetic beta-lactam antibiotics].

The acute toxicity, local tolerance and pharmacokinetic properties of sulbactame manufactured by the Iaşi Antibiotic Investigation Centre, alone or in association with ampicillin or amoxicillin were tested. Some tests were made comparatively with the product Unasyn--Pfizer. The obtained data show that this beta-lactamase inhibitor has a low toxicity--DL50 i.p. in mice over 4,000 mg/kg, both alone or associated with the two semisynthetic beta-lactamic antibiotics. The local tolerance is good and the serum levels of the above mentioned associations are above towards the tested bacteria and are similar or very close to those of Unasyn. It is believed that the therapeutical use of the association sulbactame + ampicillin or sulbactame + amoxicillin is very useful in the beta-lactamase producing germs infection.

Amoxicillin↗
PubMedDate not supplied

The role of some prostaglandin analogues in experimental intoxication produced by carbon tetrachloride in rats.

Prostaglandins are synthesized ubiquitously in the body from unsaturated fatty acids and they act as paracrine messengers. We have studied the influence of a prostaglandin analogue on experimental induced hepatopathy. The tested compound is a synthetic isopropyl ester of PGF2 alpha (IPEF) and as hepato-toxic agent we used CCl4. We worked on four groups of 4 adult male rats each. Group I received no substance; Group II received CCl4 0.1 ml/bw/per os, single dose, for three days; Group III received CCl4 as series I and IPEF 15 micrograms/bw i.p., single dose daily, one hour before CCl4 administration; Group IV received CCl4 as series I and IPEF 50 micrograms/bw i.p., single dose daily. Twenty-four hours after the last administration, samples of blood were taken and ALT, AST, LDH as well as conjugate and unconjugate bilirubin were determined. We also determined MDH, GSH and glutathion peroxidase, in liver homogenate. Our data show that MDH levels are increased in Group I (20.81 +/- 3.15 microM/microgram protein) as compared with both Group III (8.44 +/- 1.32 microM/microgram protein) and IV (7.31 +/- 1.92 microM/microgram protein) which might suggest that prostaglandin analogue IPEF decreases the polyunsaturated fatty acids degradation, at both low and high level. ALAT levels for group that received CCl4 (782 +/- 20.8 U/L) are significantly higher than those for group III (264 +/- 15.4 U/L) and IV (227 +/- 8.4 U/L) which received IPEF at low, respectively high dose. Our data suggest that the synthetic prostaglandin analogue presents stabilizing membrane effects (plasmatic and membrane of some cellular organelles) and reduces peroxide radicals production.

Algorithms↗
PubMedDate not supplied

Hypolipidemic effect of a prodrug containing nicotinic acid in rats. Correlation with plasmatic levels.

We have studied a macromolecular prodrug that contains nicotinic acid bound on a polymeric support of dextran. We have determined plasmatic levels of nicotinic acid, by a HPLC method, after macromolecular conjugate administration for a 24 hours period. In order to study the hypolipidemic effect, triglyceride levels were determined and correlated with plasmatic levels of nicotinic acid. The obtained data show that, starting from 6 hours after polymeric conjugate administration, plasmatic levels of nicotinic acid are high enough to determine a significantly decrease in triglycerides level. As a conclusion we assume that the active substance was gradually released from the polymeric support leading to a prolonged presence of the active substance in the body, which caused a lowered triglycerides level.

Analysis of Variance↗
PubMedDate not supplied

[Study of the cardiovascular properties of some new methyl-xanthine derivatives].

The effects of some new methylxanthine compounds, derivatives of theophylline, theobromine and caffeine with various radicals in 8 position on blood pressure have been studied. Derivatives of theophylline (1,3-dimethyl-xanthine) with various radicals in 8 position have reduced the blood pressure. In the same experimental conditions the theobromine (3,7-dimethyl-xanthine) derivatives haven't modified the blood pressure while the caffeine (1,3,7-trimethyl-xanthine) derivatives have increased the blood pressure values.

Algorithms↗
PubMedDate not supplied

[Advancements in pharmacology of and pharmacotherapy with local anaesthetics].

The local anaesthetic domain, very often implicated in the dental practice, it's in to a continuously progress from two points of view: the development of the products proposal and the improvement of the pharmacokinetic parameters. In our study we presented: new classifications of local anaesthetics, their characteristics and structure, the pharmacokinetic and pharmacodynamic parameters of local anaesthetics used in dental practice. An interesting remark of last years is represented by the fact that the local anaesthetics could also have an antibacterial effect which is often helpful in dental practice.

Anesthesia, Dental↗
PubMedDate not supplied

[Mechanism of action of platelet aggregation inhibitors].

The antiaggregant drugs class is registering in the last few years an increased dynamics. The action mechanism relies either on the platelet activator pathway inhibition, or on the natural inhibitory pathway stimulation. The most frequently implied action mechanisms are COX inhibition, the cyclic nucleotides synthesis inhibition, ADP receptor's inhibition, TxA2 synthesis/action's inhibition, the fibrinogen receptor's blocking. The foreseen introduction of new antiaggregant drugs does have in view the von Willebrand factor-GP I interaction's inhibition, NO releasing, the platelet activation's inhibition using thrombin, the collagen--platelet interaction's inhibition. The widening of this drugs class, established by the constant creation of new antiaggregants, is leading to a doubtless result, meaning the prognosis improvement of certain diseases, in which the platelet activation is a key link of the pathogenic mechanism.

Cardiovascular Diseases↗
PubMedDate not supplied

[The method of conditioned place preference in pharmaco-dependence research].

Conditioned place preference (CPP) is a paradigm for evaluating pharmaco-dependence related issues besides other animal models (withdrawal syndrome evaluation, self administration, behavioural sensitisation, drug discrimination). CPP is used for evaluation of motivational properties of substances (but also for non pharmacological stimulus). It consists in repeated association between a primary unconditioned properties of a stimulus (usually a substance) with a distinct environment. After a number of such associations, the unconditioned stimulus become conditioned stimulus and may emerge a response when the animal is exposed to these (the conditioned compartment). The response may be quantified as the time spent in the conditioned compartment. Our studies show an agreement between misoprostol (stable PGE1 analogue) effect on alleviating morphine-induced experimental pharmaco-dependence and morphine-induced CPP.

Animals↗
PubMedDate not supplied

[The effect of antihypertensive drugs on the anaesthetic effect of lidocaine in hypertensive patients who need dental treatment].

The study evaluated the influence of atenolol/nifedipine on the local anaesthesia with lidocaine in 64 patients with essential arterial hypertension following dietetic regimen and divided in: control group (21 patients), atenolol-treated group (21 patients with atenolol therapy) and nifedipine-treated group (22 patients with nifedipine therapy). Atenolol/nifedipine was administrated three hours before anaesthesia (1.5 mg lidocaine/kg body weight) applied on Spix Spina. The atenolol/nifedipine influence on the anaesthetic intensity was evaluated both by the patient and dentist using scales for the appreciation of pain intensity (Visual Analogue Scale, Numerical Rating Scale) at 0 minutes (before anaesthesia), 5, 10, 20, 30, 60 minutes (moments for the determination of lidocaine plasmatic concentrations). There were no statistically significant differences between the values appreciated by the patient and dentist. Our data demonstrated a significant decrease of pain intensity in patients treated with atenolol/nifedipine. Very good inverse correlation was found between lidocaine concentrations and pain intensity.

Anesthesia, Dental↗