Marija Pavlović

A Surgical Reentry Study on the Influence of Platelet-Rich Plasma in Enhancing the Regenerative Effects of Bovine Porous Bone Mineral and Guided Tissue Regeneration in the Treatment of Intrabony Defects in Humans

BACKGROUND The purpose of this study was to evaluate the additional benefits provided by the incorporation of platelet-rich plasma (PRP) into a regenerative protocol consisting of bovine porous bone mineral (BPBM) and guided tissue regeneration (GTR) in the treatment of intrabony defects in humans. METHODS Twenty-three paired intrabony defects were surgically treated using a split-mouth design. Defects were treated with BPBM/GTR/PRP (experimental group) or with BPBM/GTR (control group). The clinical parameters evaluated included changes in probing depth, clinical attachment level, and defect fill as revealed by reentry surgeries at 6 months. RESULTS Preoperative probing depths, attachment levels, and transoperative bone measurements were similar for the two groups. Post-surgical measurements taken at 6 months revealed that both treatment modalities resulted in a significant decrease in probing depth, gain in clinical attachment, and bone fill of the defects compared to baseline. Postoperative differences observed between the two groups were 0.72 +/- 0.36 mm at buccal sites and 0.90 +/- 0.32 mm at lingual sites for probing depth, 0.82 +/- 0.41 mm at buccal sites and 0.78 +/- 0.38 at lingual sites for gain in clinical attachment, and 0.85 +/- 0.36 mm at buccal sites and 0.94 +/- 0.42 mm at lingual sites for defect fill, all favoring the experimental sites. However, none of the differences were statistically significant. CONCLUSION Within the limitations related to using a small sample size, PRP did not significantly augment the effects of BPBM and GTR in promoting the clinical resolution of intrabony defects.

Traditional wound-healing plants used in the Balkan region (Southeast Europe)

ETHNOPHARMACOLOGICAL RELEVANCE The geographical and ecological specificity of the Balkan Peninsula has resulted in the development of a distinct diversity of medicinal plants. In the traditional culture of the Balkan peoples, plants have medicinal, economic and anthropological/cultural importance, which is reflected in the sound knowledge of their diversity and use. This study analyses the traditional use of medicinal plants in the treatment of wounds and the pharmacological characteristics of the most frequently used species. MATERIALS AND METHODS A detailed analysis of the literature related to ethnobhe uses of medicinal plants in the Balkan region was carried out. Twenty-five studies were analysed and those plants used for the treatment of wounds were singled out. RESULT An ethnobotanical analysis showed that 128 plant species (105 wild, 22 cultivated and 1 wild/cultivated) are used in the treatment of wounds. Their application is external, in the form of infusions, decoctions, tinctures, syrups, oils, ointments, and balms, or direct to the skin. Among those plants recorded, the most commonly used are Plantago major, Hypericum perforatum, Plantago lanceolata, Achillea millefolium, Calendula officinalis, Sambucus nigra, Tussilago farfara and Prunus domestica. The study showed that the traditional use of plants in wound healing is confirmed by in vitro and/or in vivo studies for P. major and P. lanceolata (3 laboratory studies for P. major and 2 for P. lanceolata), H. perforatum (5 laboratory studies and 3 clinical trials), A. millefolium (3 laboratory studies and one clinical trial), C. officinalis (6 laboratory studies and 1 clinical trial), S. nigra (3 laboratory studies) and T. farfara (one laboratory study). CONCLUSION The beneficial effects of using medicinal plants from the Balkan region to heal wounds according to traditional practices have been proven in many scientific studies. However, information on the quantitative benefits to human health of using herbal medicines to heal wounds is still scarce or fragmented, hindering a proper evaluation. Therefore, further studies should be aimed at isolating and identifying specific active substances from plant extracts, which could also reveal compounds with more valuable therapeutic properties. Furthermore, additional reliable clinical trials are needed to confirm those experiences encountered when using traditional medicines. A combination of traditional and modern knowledge could result in new wound-healing drugs with a significant reduction in unwanted side effects.

Plant waste materials from restaurants as the adsorbents for dyes

This paper has demonstrated the valorization of inexpensive and readily available restaurant waste containing most consumed food and beverage residues as adsorbents for methylene blue dye. Coffee, tea, lettuce and citrus waste have been utilized without any pre-treatment, thus the adsorption capacities and dye removal efficiency were determined. Coffee waste showed highest adsorbent capacity, followed by tea, lettuce and citrus waste. The dye removal was more effective as dye concentration increases from 5 up to 60 mg/L. The favorable results obtained for lettuce waste have been especially encouraged, as this material has not been commonly employed for sorption purposes. Equilibrium data fitted very well in a Freundlich isotherm model, whereas pseudo-second-order kinetic model describes the process behavior. Restaurant waste performed rapid dye removal at no cost, so it can be adopted and widely used in industries for contaminated water treatment.

The chemometric study and quantitative structure retention relationship modeling of liquid chromatography separation of ziprasidone components.

Optimization of the experimental conditions of a novel HPLC method for determination of the impurity levels with ziprasidone (in bulk substance and pharmaceutical dosage forms) was performed with use of Multi-Layer Perceptron (MLP) Artificial Neural Networks (ANN) and Response Surface Plots. The obtained experimental conditions were further used to test a set of 20 reversed-phase columns for their selectivity towards ziprasidone components by use of the principal component analysis (PCA) and hierarchical clustering analysis (HCA). The obtained HPLC retention times of ziprasidone and its impurities (Imp I-V) along with the computed molecular parameters of the examined compounds were further used in the Quantitative Structure Retention Relationship (QSRR) study. The performed QSRR study has selected the LogD(pH 1.5), LogD(pH 2.5), LogD(pH 4.0), LogP, MS, and SAS parameters as descriptors of the chromatographic behavior of ziprasidone components. The developed QSRR model can be very useful in the tR prediction for the ziprasidone derivatives (impurities, degradation products, and metabolites). As the performed LC-MS study of the test solution has confirmed that the unknown impurity (t(R): 11.270 min) in the test solution is the TS1, one from two candidates predicted by QSRR (TS1 and TS5), the high prediction potential of the created QSRR models has been proved.

Dual effect of benzyl alcohol on α-glucosidase activity: efficient substrate for high yield transglucosylation and non-competitive inhibitor of its hydrolytic activity.

Benzyl alcohol, a potent anesthetic and bacteriostatic, can be efficiently glucosylated by α-glucosidase from Saccharomyces cerevisiae to produce benzyl alcohol α-glucoside with a 75% yield. However, while studying the transglucosylation reaction conditions, it was found out that benzyl alcohol is a non-competitive inhibitor of α-glucosidases hydrolytic activity (Ki=18mM, toward maltose). Due to its interesting ability to be glycosylated by the enzyme and to inhibit its hydrolytic activity, we proposed a plausible mechanism for the phenolic α-glucosydase inhibitors binding, since the mechanism of inhibition has not yet been elucidated.

Biological treatment of colored wastewater by Streptomyces fulvissimus CKS 7

This study aims to investigate the biological processes related to the biodegradable potential of growing microbial cells for contaminated water treatment. Thus, the use of the Streptomyces fulvissimus CKS 7 (CKS7) has been evaluated for decolorizing efficiency of a solution containing a cationic triphenylmethane dye, crystal violet. The color reduction was monitored by UV-Vis spectroscopic analysis, through changes in their absorption spectrum and comparing the results with those of the respective controls. It was found that the CKS7 performed well and reached up to 100% effectiveness. The required process parameters have been apparently mild and include the reaction temperature of 27-30 °C, 10% inoculum size, under shaking conditions, whereas the time course of decolorization had been concentration dependent. A possible mechanism for removing dye from the working medium was accomplished in two steps: the binding of the dye on the bacterial cell surface, in addition to the dye biodegradation by the bacterial intracellular enzymes. After one cycle of the complete dye removal, the adapted culture was successfully reused for the same purpose. The phytotoxicity analysis revealed that non-toxic compounds were present in decolorized medium, indicating that the CKS7 bacteria seem to be a promising application for contaminated water treatment.

Utilization of spent coffee grounds for isolation and stabilization of Paenibacillus chitinolyticus CKS1 cellulase by immobilization

This study has explored the feasibility of using spent coffee grounds as a good supporting material for the Paenibacillus chitinolyticus CKS1 cellulase immobilization. An optimal operational conditions in a batch-adsorption system were found to be: carrier mass of 12 g/L, under the temperature of 45 °C and no pH adjustments. The immobilization yield reached about 71%. An equilibrium establishment between the cellulase and the carrier surface occurred within 45 min, whereas the process kinetics may be predicted by the pseudo-second-order model. An immobilized cellulase preparation expressed very good avicelase activity, this reached up to 2.67 U/g, and revealed an improved storage stability property, compared to free enzyme sample counterpart. The addition of metal ions, such as K+ and Mg2+ did not affect positively immobilization yield results, but on the contrary, contributed to an improved bio-activities of the immobilized cellulase, thus may be employed before each enzyme application. The method developed in this study offers a cheap and effective alternative for immediate enzyme isolation from the production medium and its stabilization, compared to other carriers used for the immobilization.

A study of transglucosylation kinetic in an enzymatic synthesis of benzyl alcohol glucoside by α-glucosidase from S. cerevisiae

Abstractα-1,4-Glucosidase from Saccharomyces cerevisiae is an enzyme which is widely used in synthesis of different drugs. Glucosidase inhibitors are studied as potential drugs for prevention of HIV and diabetes. For understanding of these processes it is very important to have insights in the transglucosylation activity of this enzyme. In this paper the kinetics of transglucosylation reaction catalyzed by this enzyme in the synthesis of benzyl alcohol glucoside was studied and all relevant kinetic constants for this system are found. It was shown one additional property of transglycosylation reactions catalyzed by glycosidases—inhibition by both, glucose acceptor and glucose donor, and mechanisms for these inhibitions were proposed.

Plant growth‐promoting bacteria elevate the nutritional and functional properties of black cumin and flaxseed fixed oil

BACKGROUND In order to study the influence of plant growth-promoting bacteria (PGPB) belonging to Streptomyces sp., Paenibacillus sp., and Hymenobacter sp. on fixed oil content of flaxseed and black cumin, 2-year field experiments were conducted. PGPB was applied during seedtime of plants. The extraction of oil from seeds was performed using supercritical CO2 . RESULTS The addition of PGPB significantly increases the content of C18:1 (from 16.06 ± 0.03% to 16.97 ± 0.03%) and C18:3 (from 42.97 ± 0.2% to 45.42 ± 0.5%) in flaxseed oil and C18:2 (from 52.68 ± 0.50% to 57.11 ± 0.40%) and C20:2 (from 4.34 ± 0.02% to 4.54 ± 0.03%) in black cumin seed oil. The contents of total polyphenols, flavonoids, and carotenoids, as well as antioxidant activity measured by ferric-reducing ability of plasma assay, were found to be greater in the oil from the seeds of plants treated with the PGPB, compared with the respective non-treated samples. CONCLUSION The use of PGPB enhances plant nutritive properties; these represent a great source for obtaining valuable functional food ingredients.

Different Potassium Channels are Involved in Relaxation of Rat Renal Artery Induced by P1075

The ATP‐sensitive K+ channels opener (KATPCO), P1075 [N‐cyano‐N′‐(1,1‐dimethylpropyl)‐N″‐3‐pyridylguanidine], has been shown to cause relaxation of various isolated animal and human blood vessels by opening of vascular smooth muscle ATP‐sensitive K+ (KATP) channels. In addition to the well‐known effect on the opening of KATP channels, it has been reported that vasorelaxation induced by some of the KATPCOs includes some other K+ channel subtypes. Given that there is still no information on other types of K+ channels possibly involved in the mechanism of relaxation induced by P1075, this study was designed to examine the effects of P1075 on the rat renal artery with endothelium and with denuded endothelium and to define the contribution of different K+ channel subtypes in the P1075 action on this blood vessel. Our results show that P1075 induced a concentration‐dependent relaxation of rat renal artery rings pre‐contracted by phenylephrine. Glibenclamide, a selective KATP channels inhibitor, partly antagonized the relaxation of rat renal artery induced by P1075. Tetraethylammonium (TEA), a non‐selective inhibitor of Ca2+‐activated K+ channels, as well as iberiotoxin, a most selective blocker of large‐conductance Ca2+‐activated K+ (BKCa) channels, did not abolish the effect of P1075 on rat renal artery. In contrast, a non‐selective blocker of voltage‐gated K+ (KV) channels, 4‐aminopyridine (4‐AP), as well as margatoxin, a potent inhibitor of KV1.3 channels, caused partial inhibition of the P1075‐induced relaxation of rat renal artery. In addition, in this study, P1075 relaxed contractions induced by 20 mM K+, but had no effect on contractions induced by 80 mM K+. Our results showed that P1075 induced strong endothelium‐independent relaxation of rat renal artery. It seems that KATP, 4‐AP‐ and margatoxin‐sensitive K+ channels located in vascular smooth muscle mediated the relaxation of rat renal artery induced by P1075.