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.     

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.     

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.     

The influence of some prostaglandin analogous on the female rat ovary and uterine tube epithelium

The synthetic analogous of the prostaglandins are utilized in the obstetrical and gynecological therapy for multiple purposes. 4 lots with 12 nonpregnant female rats were use: the Ist received 25 g/kg/day isopropyl ester PGF2; the IInd lot received 50 g/kg/day isopropyl ester PGF2; the IIIrd lot received 50 g/kg/day optic active cloprostenol; the IVth lot was the witness lot. The medication was intraperitoneally (i.p.) administrated in a unique daily dose. Prostaglandin F2 analogous at small doses (25 micrograms/kg/day) induce vasodilating effects on the ovary blood vessels and functional luteolysis rather than structural luteolysis. Both of the prostaglandins analogous at doses of 50 micrograms/kg/day present obvious vasodilating and luteolytic effects, although the intensity of the phenomenon is not the same, cloprostenol is more active, inducing a more obvious vasodilatation and luteolysis.     

Comparative Evaluation of Two Bracket Systems’ Kinetic Friction: Conventional and Self-Ligating

Friction is an intensely studied feature in orthodontics, as the sliding mechanics approach remains one of the most utilized techniques in current practice, and the question of whether self-ligating brackets produce less friction than conventional brackets still stands. The objective of this study was to compare a self-ligating system with different closing mechanisms and a conventional system with different ligating mechanisms regarding their frictional properties. Laboratory measurements were performed using an advanced materials testing machine generating tensile strength and load at maximum Load values, which were statistically analyzed and compared. These two parameters have been associated with the frictional resistance generated at the archwire–bracket slot interface. Statistically significant results were obtained when comparing the active self-ligating brackets with the passive self-ligating (tensile strength mean 1.953, SD 0.4231; load at maximum moad mean 6.000, SD 1.3000) and conventional brackets (tensile strength mean 1.953, SD 0.4231; load at maximum load mean 6.000, SD 1.3000), as well as when comparing the passive self-ligating brackets with the conventional brackets (tensile strength mean 1.708, SD 0.8628; load at maximum load mean 5.254, SD 2.645). The active self-ligating brackets tended to produce more friction when compared to the passive self-ligating brackets but were similar to conventional brackets with stainless steel ligatures.     

Beneficial effects of Aloe ferox on lipid profile,blood pressure,and glycemic control in obese persons: A CONSORT-clinical study

Background:Aloe ferox is one of the most widely used medicinal plants today, with the most intense detoxifying action of all aloe species, being used in the treatment of various diseases, including obesity. Our study aimed to assess the efficacy of Aloe ferox in obesity treatment.Methods:The study sample included 20 Romanian persons with obesity treated with diet and Aloe ferox based supplements, and 20 Romanian matched controls treated with diet and a placebo. The treatment included 2 capsules/day (Aloe ferox 460 mg) for 2 weeks, followed by a 2-week break, repeated 3 times. The blood pressure (systolic and diastolic) and anthropometric parameters, such as body mass index (BMI), total cholesterol, and abdominal circumference, as well as the biochemical parameters, fasting blood glucose (FBG), uric acid, and lipid profile was evaluated at baseline and after 3 months.Results:After 3 months of Aloe ferox administration, significant differences between the study group and the control group were observed regarding BMI (P = .03), total cholesterol (P = .032), low-density lipoprotein cholesterol (LDLc) (P = .01) and FBG (P = .018). Also, between the initial clinical, anthropometric, and biological parameters and those after the administration of Aloe ferox in the study group, we obtained significant differences regarding BMI (P = .002), LDLc (P = .039), fasting glycemia (P < .001) and diastolic blood pressure (P = .006).Conclusions:The administration of Aloe ferox to obese patients has been shown to achieve a significant reduction in body weight, BMI, LDLc, and FBG. These effects may be due to the laxative and detoxifying action of Aloe ferox components. As it can only be administered for limited periods due to side effects, further experimental and human studies of the efficacy of this plant in the treatment of obesity are needed.     

Mechanical Properties of Orthodontic Cements and Their Behavior in Acidic Environments

The present research is focused on three different classes of orthodontic cements: resin composites (e.g., BracePaste); resin-modified glass ionomer RMGIC (e.g., Fuji Ortho) and resin cement (e.g., Transbond). Their mechanical properties such as compressive strength, diametral tensile strength and flexural strength were correlated with the samples’ microstructures, liquid absorption, and solubility in liquid. The results show that the best compressive (100 MPa) and flexural strength (75 Mpa) was obtained by BracePaste and the best diametral tensile strength was obtained by Transbond (230 MPa). The lowestvalues were obtained by Fuji Ortho RMGIC. The elastic modulus is relatively high around 14 GPa for BracePaste, and Fuji Ortho and Transbond have only 7 GPa. The samples were also subjected to artificial saliva and tested in different acidic environments such as Coca-Cola and Red Bull. Their absorption and solubility were investigated at different times ranging from 1 day to 21 days. Fuji Ortho presents the highest liquid absorption followed by Transbond, the artificial saliva has the best absorption and Red Bull has the lowest absorption. The best resistance to the liquids was obtained by BracePaste in all environments. Coca-Cola presents values four times greater than the ones observed for artificial saliva. Solubility tests show that BracePaste is more soluble in artificial saliva, and Fuji Ortho and Transbond are more soluble in Red Bull and Coca-Cola. Scanning electron microscopy (SEM) images evidenced a compact structure for BracePaste in all environments sustaining the lower liquid absorption values. Fuji Ortho and Transbond present a fissure network allowing the liquid to carry out in-depth penetration of materials. SEM observations are in good agreement with the atomic force microscopy (AFM) results. The surface roughness decreases with the acidity increasing for BracePaste meanwhile it increases with the acidity for Fuji Ortho and Transbond. In conclusion: BracePaste is recommended for long-term orthodontic treatment for patients who regularly consume acidic beverages, Fuji Ortho is recommended for short-term orthodontic treatment for patients who regularly consume acidic beverages and Transbond is recommended for orthodontic treatment over an average time period for patients who do not regularly consume acidic beverages.     

Water Sorption and Solubility of Flowable Giomers

The objective of this study is the characterization of a novel experimental flowable giomer (G) regarding water sorption, water solubility, and the microstructural characteristics, in comparison to three commercial giomers: Beautifil flow Plus X F00 (B-F00), Beautifil flow F02 (B-F02) and Beautifil flow Plus X F03 (B-F03), Shofu, Kyoto, Japan. Methods: Water sorption/solubility was performed by weighing the specimens before and after water immersion for 1, 2, 3, 14, 21 and 30 days. Data analysis was carried out with the software Origin2019b Graphing & Analysis using the ANOVA test and the Tukey test for post hoc comparison of the groups of materials. The microstructural analyses were done with a scanning electron microscope (SEM) and an atomic force microscope (AFM). The results showed significant differences between the tested materials (p < 0.05). For sorption, the Tukey test indicated differences between all four sample groups, except between B-F02 and B-F03, which exhibited no differences in any of the investigation days. The Tukey test also showed significant differences regarding solubility between all sample groups in the 30-day interval. SEM images and roughness showed that after 30 days of immersion in water, the experimental giomer G had the roughest surface.