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BACKGROUND: The new type of virus (SARS-CoV-2 or COVID-19) from Coronaviridae family, discovered in 2019, caused a global pandemic with several massive lock-downs around the globe. Science and politicians became the center of world attention, receiving many questions without having clear answers. The hopes of many rested on vaccine development, which was done fast, facing novel challenges such as the massive production and distribution for several billions of people. OBJECTIVE: In this paper, the global reaction to the pandemic is reviewed along with some critical comments. METHOD: Different groups, including nations, took part in global lockdowns, while vaccine development was running in parallel without having enough capacity for some of the biggest medical demands in history. This review will bring together views from all interested groups in this pandemic crisis. RESULTS: The Western world waited too long (4 months), after the first case was confirmed in China, to introduce lock-down and safety measures. On the other side, vaccine development was done too fast to give clear long-term safety profiles of the medications developed. Due to the focus on development, it was overlooked that production and distribution of sterile products such as vaccines might have limitations globally. Usually when such limitations occur, power comes to the surface. Therefore, buyers who had power will get the vaccines they need first. However, we should recognize the economic impact that directly influenced healthcare funding. All of this will lead to post-crisis challenges, including depression, violence, suicide, migration, and many other social problems. CONCLUSIONS: The COVID-19 pandemic is a test for all of us, which many governments, industries and non-state actors are failing. It is a perfect “general probe” to detect some of the weaknesses of the current structure of global health. If politics and science do not work together to make a global production plan for vaccines and learn from this pandemic, then all of the lives lost were for nothing.

Background: A spray pattern (SP) test is one of the most challenging in vitro tests for nasal spray products (NSPs) associated with a high degree of variation. The total results variation observed in such studies should be in major part representative of product performance to assure high confidence when making conclusions based on obtained results. Analytical methods should be developed in a way to minimize variation contribution of random factors. A systematic statistical assessment of sources of variation is encouraged to be performed during any method development. Methods: This study includes the development of a product-shaking procedure, definition of in vivo relevant actuation parameters, and the development of a robust SP method considering NSP behavior. The final SP method is tested on different days and in different laboratories to evaluate the contribution of individual factors and interactions to the observed variance in SP using a gauge repeatability and reproducibility (GRR) model. Results: It was found that the time lag between consecutive actuations significantly influences the variability of the SP area, suggesting the importance of determining a recovery period. Factor analyst was not found to be important. Factor day was found to have the potential to impact results, mostly through interactions with other factors, suggesting that one should pay attention when performing any comparative studies within the same laboratory on different days. Significant differences were observed when the same product was tested in different laboratories. Conclusion: Key random factors, which significantly contribute to total variation, were identified using a GRR approach. By applying an appropriate control strategy over these factors, one can assure that assessed total variation can be representative of product performance. The same general approach is not only applicable to development of SP method for NSP but to all types of analytical testing as well.

The aim of this work is to evaluate average bioequivalence (ABE) and population bioequivalence (PBE) statistical approaches so as to identify which approach is most suitable for in vitro bioequivalence (IVBE) testing of nasal spray products. For droplet size distribution (DSD) and spray pattern (SP), in vitro data were collected using a well-established nasal spray on the market (Nasonex®, manufactured by Merck Sharp & Dohme Limited). Simulations were performed using in vitro data to comparatively investigate ABE and PBE tests. For highly variable parameters such as SP area, this study clearly demonstrates that the level of agreement between ABE and PBE test conclusions is much smaller as compared with that of DSD Dv(50), which was found to have moderate variability. PBE approach dictates equivalence for both means and variances, and was found to handle both SP and DSD parameters with similar passing rates compared to the passing rates from the ABE approach. However, pronounced asymmetric behavior of PBE empirical power curves for highly variable SP area was observed. A modified PBE statistical approach is proposed for DSD span and Dv(50) in vitro parameters, where acceptance criteria would be based on comparison of reference/branded product to itself as part of "pre-IVBE study" via innovative statistical bootstrap simulations. Due to inherent high variability of the SP area parameter driving pronounced asymmetric behavior of PBE power curves, and due to unclear in vivo relevance for SP area and ovality, authors propose that SP parameters be used as development and quality control tools rather than for demonstration of IVBE.

Cardioprotective effects of fullerenol C-60(OH)(24) nanoparticles (FNP) were investigated in pigs after a single treatment with doxorubicin (DOX). Semithin and ultrathin sections of myocardial tissue routinely prepared for transmission electron microscopy were analyzed. Extensive intracellular damage was confirmed in cardiomyocytes of DOX-treated animals. By means of ultrastructural analysis, a certain degree of parenchymal degeneration was confirmed even in animals treated with FNP alone, including both the oral and the intraperitoneal application of the substance. The cardioprotective effects of FNP in animals previously treated with DOX were recognized to a certain extent, but were not fully confirmed at the ultrastructural level. Nevertheless, the myocardial morphology of DOX-treated animals improved after the admission of FNP. Irregular orientation of myofibrils, myofibrillar disruption, intracellular edema, and vacuolization were reduced, but not completely eliminated. Reduction of these cellular alterations was achieved if FNP was applied orally 6 h prior to DOX treatment in a dose of 18 mg/kg. However, numerous defects, including the inner mitochondrial membrane and the plasma membrane disruption of certain cells persisted. In FNP/DOX-treated animals, the presence of multinuclear cells with mitosis-like figures resembling metaphase or anaphase were observed, indicating that DOX and FNP could have a complex influence on the cell cycle of cardiomyocytes. Based on this experiment, further careful increase in dosage may be advised to enhance FNP-induced cardioprotection. These investigations should, however, always be combined with ultrastructural analysis. The FNP/DOX interaction is an excellent model for the investigation of cardiomyocyte cell death and cell cycle mechanisms.

The aim of this work is to use an experimental design approach to identify and study influential formulation and delivery device properties, which can be controlled by final product manufacturer, to establish design space, within which desired in vitro performance can be reached.Combining three factors, viscosity of suspension, nozzle orifice diameter (OD), and shot weight (SW), at three levels resulted in D-optimal experimental design with 20 runs. Responses within this study were droplet size distribution (DSD) and spray pattern (SP) in vitro tests. In addition, the amount of mechanical work needed for actuation was integrated from force profiles and used as a response. Results were fit to quadratic model by regression, which allowed also for determination of second-order and interaction effects between factors. Models were further optimized by keeping significant terms only. Optimized models were used to create response surfaces and design space with confidence levels.Viscosity has a dominant effect on DSD and modest effect on SP, with lower viscosities related to generation of smaller DSD and larger SP. Orifice diameter was found to have the highest impact on SP, with larger diameter resulting in larger SP. This effect was additionally confirmed by results of Plume Geometry in vitro test. Shot weight factor exerts significant influence on all tested metrics. Work, however, did not vary greatly with suspension viscosity or orifice diameter. Shot weight is the most dominant factor for work and important for DSD having a positive effect on both responses. In the case of SP, its relationship with shot weight is described by second-order polynomial fit. Inspection of raw data revealed that density of droplets within SP area is different for different shot weights.Presented study elucidated an inherent relationship between factors and responses and established mathematical models (response surfaces) for predictive purposes to target specific in vitro performance of nasal sprays by appropriate specification of factors, taking into account control space with included risk and uncertainty analysis.

The aim of the present study was to evaluate the effect of long-term swimming exercise in conjunction with a high fat mixed lipid (HFML) diet on colon cancer (CC) development and lipid peroxidation in the large bowel. We used forty male Wistar rats, which were randomly divided into one control group and four cancer groups: sedentary and swimming groups fed a standard diet (LFCO) and sedentary and swimming groups fed an HFML diet. Corticosterone was determined during the experiment. After 6 months of swimming, the rats were sacrificed and blood, heart, liver, muscle and large bowel were taken for determining the activity of serum enzymes, antioxidant capacity and CC development. The results demonstrate that exercise has a protective role in CC development. Attenuated development of CC and increased levels of malondialdehyde (MDA) in the large bowel of exercised rats show that one of the protective effects of exercise on developing CC is induction of oxidative stress. However, in terms of the combined effects of dietary fat and exercise, our results indicate that the protective role of exercise on CC development is significantly depressed by an HFML diet. An HFML diet significantly reduced the protective influence of exercise on colon carcinogenesis in rats and affected the degree of peroxidation in the large bowel during exercise, as well as concentrations of serum enzymes (LDH, α-HBDH, CK, ALT and AST). Our results indicate that an HFML diet, which reflects the composition of a Western style diet, is a significant modifier of the protective effects of exercise on CC development in rats.

In this study, a fast and simple analytical method for determination of urinary 18β-glycyrrhetinic acid (18-GA), without any sample purification prior to the analysis, was developed. The method was successfully applied to determine the 18-GA concentration in real urine samples obtained after ingestion of glycyrrhizin. The method was shown to be specific, accurate, linear over the tested range (correlation coefficients 0.999), and repeatable (RSD below 0.2 and 3.0% for retention time and peak area, respectively). A new multi-variable-at-a-time (MVAT) approach for robustness testing gives RSD values of 0.6 and 3.8% at “−1” level, and 4.7 and 12.3% at “+1” level compared to the optimal “zero” level for retention time and peak area, respectively.

Proteinuria, i.e. increased excretion of proteins in urine, is a common sign indicating renal or urinary tract diseases. In this study, a fast and simple procedure for urine sample preparation and capillary micellar electrokinetic chromatographic analysis is presented, without any sample pretreatment prior to the analysis. The developed MEKC method was employed for simultaneous determination of albumin (ALB), haemoglobin (HGB), and myoglobin (MYO) in human urine samples obtained from patients with diagnosed proteinuria. Optimum conditions for detection and separation of ALB, HGB, and MYO are 50 mmol L−1 borate buffer containing 20 mmol L−1 SDS (pH 9.3), injection 40 mbar × 20 s, voltage 25 kV, temperature 30 °C, and detection wavelength 200 nm. The method was shown to be specific, accurate, linear (correlation coefficients r2 > 0.99), and precise (RSD below 3.75 and 7.23% for migration time and peak area, respectively). Multi-variable-at-a-time (MVAT) approach for robustness testing shows no significant variations in accuracy, specificity, and precision as RSD values were lower than 5 and 10% for migration time and peak area, respectively. The presented method is applicable for routine analyses of urine samples as a screening method for patients with excess ALB, HGB, and MYO.

A new micellar electrokinetic capillary chromatographic (MEKC) method has been developed for simultaneous quantitation of atorvastatin and its related substances. The separation was carried out in an extended light path capillary at applied voltage of 30 kV using a background electrolyte consisting of 10 mM sodium tetraborate buffer pH 9.5, 50 mM sodium dodecyl sulphate and 20% (v/v) methanol. The addition of methanol to the running buffer resulted in a very effective choice to achieve resolution between the peaks of charged substances adjacent to atorvastatin as well as the peaks of neutral drug-related substances. Linear calibration curves were established over the concentration range 100-1200 µ ; ; g mL-1 for atorvastatin and 1.0-12.5 µ ; ; g mL-1 for related substances. The proposed MEKC procedure has been validated with respect to selectivity, precision, linearity, limits of detection, and quantitation, accuracy and robustness. The method has been successfully applied to the determination of atorvastatin and purity evaluation of bulk drug and formulated products.

The aim of this study was to investigate the possible protective role of fullerenol (FLR, C(60)(OH)(24) on doxorubicin (DOX)-induced lung toxicity using biochemical and histopathological approaches. Rats (Sprague-Dawley outbred) were randomly divided into five groups. The healthy control group received no medication (saline only). The other four groups had chemically induced breast cancer (1-methyl-1-nitrosourea; 50 mg/kg, ip). The second group was the cancer control group (saline only). The other three groups were DOX (8 mg/kg, ip), FLR/DOX (100 mg/kg, ip, 30 min before DOX; 8 mg/kg, ip), and FLR (100 mg/kg, ip), respectively. The levels of malondialdehyde (MDA) and oxidized glutathione (GSSG) in the lung tissue were higher in the group treated with DOX alone than in the control groups. The activities of catalase (CAT), glutathione reductase (GR), superoxide dismutase (SOD), and lactate dehydrogenase (LDH) were found to be increased in the lung tissue of the animals in the DOX group over all the other groups, while GSH-Px significantly decreased in activity compared with the control and FLR groups. There was no significant difference in MDA and GSSG levels and enzyme activities in either control (healthy; cancer) or FLR (FLR/DOX; FLR) groups. The acute change found in the DOX group was subpleural edema. In contrast, the groups treated with FLR appeared to be virtually histopathologically normal. In conclusion, this study clearly indicates that DOX treatment markedly impairs pulmonary function and that pre-treatment with FLR might prevent this toxicity in rats through inhibition of oxidative stress.

Paracetamol (PAR) crystals exhibit poor compressibility, poor flowability and its tablets show a tendency to cap. To improve the mechanical strength of tablets several kinds of “Paracetamol for direct compression” are present on the market. Current research demonstrated the best tablet properties with coated paracetamol (mass of tablets, diameter, height and mechanical strength, friability RSD

Since the introduction of Doxorubicin (Dox) for the treatment of cancer in 1969, this compound has demonstrated high antitumor efficacy. Dox's use in chemotherapy has been limited largely due to its diverse toxicities, including cardiac, liver, renal, pulmonary, hematological and testicular toxicity. Various attempts have been made to reduce Dox-induced toxicity. These include dosage optimization, synthesis and use of analogues. Moreover, a number of agents have been investigated as protective agents during Dox therapy. Polyhydroxilated derivatives of fullerene, named fullerenols C60(OH)n, are being extensively studied due to their great potential as antioxidants. It is proposed that they might act as free radical scavengers in biological systems, in xenobiotics-induced oxidative stress as well as against radioactive irradiation. We have investigated the effects of fullerenol C60(OH)24 (Frl) at doses of 25, 50 and 100 mg kg-1 week (for a time-span of three weeks) on heart and liver tissue after Doxorubicin (Dox)-induced toxicity in rats with colorectal cancer. In the present study, in vivo Wistar male rat model was used to explore whether Frl could protect against Dox-induced (1.5 mg/kg/week for three weeks) chronic cardio- and hepatotoxicity and compared the effect with a well-known antioxidant, vitamin C (100 mg/kg/week for three weeks). Commercially available methods were used for blood and pathohystological analysis and for the measurement of enzyme activity (SOD, MDA, GSH, GSSH, GPx, GR, CAT, CK, LDH, ?-HBDH, AST, ALT) in serum and homogenate samples of heart and liver tissues. According to macroscopic, microscopic, hematological, biochemical, physiological, pharmacological, and pharmacokinetic results, we confirmed that, at all examined doses, Frl exhibits a protective influence on the heart and liver tissue against chronic toxicity induced by Dox.

Several animal models of breast cancer have been developed to study various aspects of breast cancer biology. Substantial evidence suggests that the N-methylnitrosourea (MNU) animal model mimics human breast cancer in many respects. It has therefore been used extensively to evaluate preventive and therapeutic agents for human breast cancer. Chemically induced rodent models are also suitable for studying malignant progression. Recently, Liska et al. [7] established two protocols of MNU administration depending on the animal's age and number of applications of carcinogen, with the aim of investigating the advanced stages of mammary gland tumours. We used the same protocol as Liska but have obtained substantially different results. These results are presented and discussed in the frame of suggested key drawbacks of the MNU induced breast cancer rat model, as a contribution to the debate about the suitability of that model for evaluating preventive and therapeutic agents.

The therapeutic utility of the anthracycline antibiotic doxorubicin is limited due to its cardiotoxicity. Our aim was to investigate the efficacy of fullerenol C60(OH)24 in preventing single, high-dose doxorubicin-induced cardiotoxicity in rats with malignant neoplasm. Experiment was performed on adult female Sprague Dawley rats with chemically induced mammary carcinomas. The animals were sacrificed two days after the application of doxorubicin and/or fullerenol, and the serum activities of CK, LDH and α-HBDH, as well as the levels of MDA, GSH, GSSG, GSH-Px, SOD, CAT, GR, and TAS in the heart, were determined. The results obtained from the enzymatic activity in the serum show that the administration of a single dose of 8 mg/kg in all treated groups induces statistically significant damage. There are significant changes in the enzymes of LDH and CK (p < 0.05), after an i.p. administration of doxorubicin/fullerenol and fullerenol. Comparing all groups with untreated control group, point to the conclusion that in the case of a lower α-HBDH/LDH ratio, results in more serious the liver parenchymal damage. The results revealed that doxorubicin induced oxidative damage and that the fullerenol antioxidative influence caused significant changes in MDA, GSH, GSSG, GSH-Px, SOD, CAT, GR, and TAS level in the heart (p < 0.05). Therefore, it is suggested that fullerenol might be a potential cardioprotector in doxorubicin-treated individuals.

BACKGROUND: The European Union has forbidden the use of antibiotics as additives in animal feed. Zn-bacitracin (Zn-BC) and nystatin (NYS) were frequently used for their growth-promoting effects and for feed conversion in poultry, pigs and cattle. An HPTLC method has been developed for separating Zn-BC and NYS in the mixture, for routine quality control. RESULTS: The separation was obtained using RP-18 F254S coated HPTLC plates with acetonitrile/methanol (equal volumes):toluene:KH2PO4/KOH (buffer, pH 6.8) = 57:3:40 (v/v/v), adjusted with HCl to pH 8.2, as a mobile phase. The densitograms were monitored at 192, 215 and 305 nm and both antibiotics were assayed at 215 nm. The method was shown to be specific, accurate (recoveries were 98.7 ± 0.5% and 104.8 ± 0.7% for Zn-BC and NYS, respectively), linear over the tested range (correlation coefficients, 0.9982 and 0.9884), and precise (intermediate precision RSD below 2.2% for both analytes) with efficient separation (Rs = 3.5). CONCLUSION: The method was applied for determining Zn-BC and NYS as additives in spiked matrices of commercial animal feedstuffs. According to LOD values for each antibiotic, the minimum detectable amount in feed is 4.5 and 5.5 ppm of Zn-BC and NYS, respectively. Copyright © 2008 Society of Chemical Industry

Validation of analytical procedures is important for their efficient and reliable application. The International Conference on Harmonisation (ICH), Food and Drug Administration (FDA) and pharmacopoeia guidelines achieved a great deal in harmonising the definitions of the required validation characteristics. It is well known that poor reproducibility limits the practical implementation of capillary electrophoresis (CE). A precision study on four different MEKC methods was performed with 11 samples, containing seven antibiotics, by two analysts, in few days, on two capillary electrophoresis instruments. Five pharmaceutical preparations and three animal feeds were used. Precision was statistically analysed using migration time, peak area and height of each compound, as well as electroosmotic front (EOF). In 25 of 31 cases, the reproducibility of peak area, peak height and migration time was good (

Micellar electrokinetic capillary chromatography (MEKC) was performed at 25 degrees C and 30 kV (under a pressure of 15 mbar), using 30 mM borate buffer containing 60 mM sodium dodecysulfate (SDS) and 5% (v/v) methanol as background electrolyte (pH 9.0) to determine doxycycline. UV detection was at 350 nm. The method was shown to be specific, accurate (recovery was 100.3 +/- 1.0%), linear over the tested range (correlation coefficient 0.9995) and precise (RSD

Earlier investigation of fullerenol, C60(OH)24, features, in vitro, showed that fullerenol have strong antioxidative potential. In this work, we examined the influence of fullerenol as a potential antioxidative protector on doxorubicin induced cardiotoxicity in rats. Experiments were performed on adult Wistar rats, both gender. Animals were divided into six groups, each containing eight individuals. Doxorubicin was administrated i.v. (tail vein) in single dose of 8mg/kg. Fullerenol C60(OH)24 in treated animals was administrated i.p. (in doses 50, 100, 200 mg/kg) for 30 min. before application of doxorubicin. Control group (intact animals) was given saline (1 mL/kg). One group was treated only with fullerenol (100 mg/kg i.p.). Cardiotoxicity of doxorubicin as well as cardioprotective effects of fullerenol were evaluated following the heart function monitored by ECG recording during adrenalin i.v. infusion, and pathomorphological examination of the heart tissue. These evaluations were performed on the day 2 and 7 after doxorubicin administration. Both functional and pathomorphological investigations revealed no heart damage two days after given treatments. However, on the day 7 after doxorubicin injection, changes in cardiovascular reflexes to adrenalin as well as structural damage were manifest. The time for appearance of adrenalin-induced reflex bradicardia in ECG record was significantly longer in doxorubicin treated group in comparison with the control one. Also, pathomorphological examination of the heart tissue showed vacuolization of cardiomyocites. In fullerenol pretreated groups these described changes were ameliorated and corresponded to the control values. These results suggest that fullerenol might be potential cardioprotector in doxorubicin treated individuals.

An MEKC procedure was developed for the separation of zinc bacitracin (Zn-BC) and nystatin (NYS) in mixtures and in animal feedstuff. The running buffer was 15 mM borate/19 mM phosphate, pH 8.2, containing 20 mM SDS and 10% v/v methanol. Samples were run at 25 degrees C, the applied voltage was 25 IN, and an additional pressure of 5 mbar was applied. Both analytes were detected by LTV simultaneously at 215 nm, Zn-BC alone at 192 and 254 nm, and NYS alone at 305 nm. The method was shown to be specific, accurate (recoveries were 100.0 +/- 0.6% and 100.1 +/- 0.6% for Zn-BC and NYS, respectively), linear over the tested range (correlation coefficients 0.9991 and 0.9994), and precise (RSD below 1.3% for both analytes). The method was applied to determine Zn-BC and NYS as additives in animal feed.

This review describes the chemical synthesis of polar polyhydroxylated fullerene C60derivatives, fullerenols C60(OH)n,2≤n≤44, C60HzOx(OH)y, and polyanion fullerenols C60(OH)15(ONa)9, ranging from the very first synthetic methods up to some contemporary approaches to synthesis and separation. It also provides some basic information about physical characteristics of fullerenols. With the increasing number of hydroxyl groups, water solubility of fullerenols increases as well. Fullerenols both in water and biological media build nanoparticles of different dimensions and stability. In different chemical and biological model systems a large number of various polyhydroxylated fullerene derivatives were tested and they showed both their antioxidative and prooxidative characteristics. Several mechanisms have been proposed for the antioxidant activity of fullerenol. In addition, this paper also provides insight into patents referring to the antioxidant properties of fullerenol.

Fullerenes are a relatively new group of compounds and represent a class of sphere-shaped molecules made exclusively of carbon atoms. Since their discovery in 1985, many aspects of both fullerene and its analogues have been intensively studied to reveal their physical and chemical reactivity, as well as potential use in biological systems. Both in vitro and in vivo studies have shown that polyhydroxylated fullerene derivatives, fullerenol nanoform (C60(OH) n , n = 2-72), can be potential antioxidative agents in biological systems. This chapter represents a review of published studies of fullerenes' biological activities with special accent on the most tested fullerenol nanoform C60(OH)24.

Fullerenes are a relatively new group of compounds and represent a class of sphere-shaped molecules made exclusively of carbon atoms. Since their discovery in 1985, many aspects of both fullerene and its analogues have been intensively studied to reveal their physical and chemical reactivity, as well as potential use in biological systems. Both in vitro and in vivo studies have shown that polyhydroxylated fullerene derivatives, fullerenol nanoform (C60(OH) n , n = 2-72), can be potential antioxidative agents in biological systems. This chapter represents a review of published studies of fullerenes' biological activities with special accent on the most tested fullerenol nanoform C60(OH)24.

In this research seven ACE inhibitors (enalapril, quinapril, fosinopril, lisinopril, cilazapril, ramipril, benazepril) were studied to evaluate the correlation between their absorption and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS) and reversed-phase thin-layer chromatography (RP-TLC) hydrophobicity data (phi(0) or C-0 parameters, respectively). Their absorption values were in the range of 25-60%, while calculated KOWWIN logP values were from -0.94 to 6.61. Additionally. perindopril (absorption 70%, KOWWIN logP 2.59) and moexipril (absorption 22%, KOWWIN logP 3.36) were introduced for the theoretical considerations due to their high/low absorption values which were on the opposite sites in comparison with the majority of ACE inhibitors (25-60%). In the theoretical considerations it was shown that the solubility data (logS) must be considered, as independent variable, simultaneously with KOWWIN logP to obtain reliable correlation (r(2) = 0.7208) between absorption and ACE inhibitors lipophilicity. As the main topic of this study, the relationships between literature available and absorption data predicted by multiple linear regression (MLR) using logS values besides chromatographically obtained hydrophobicity parameters C-0 (r(2) = 0.6424) or phi(0) (r(2) = 0.6762) were studied proving that these parameters could be used in ACE inhibitors absorption evaluation. The UHPLC-MS method provides the direct application of experimentally obtained phi(0) values that is the advantage of this method. For better MLR correlation of ACE inhibitors absorption with C-0 parameters (RP-TLC) and logS, mathematical conversion of C-0 parameters to logC(0) values was necessary based on requisite for probability value of regression analysis (P lt 0.05). The accordance and differences between hydrophobicity parameters obtained by UHPLC-MS and RP-TLC were defined.

In earlier in vitro investigations, fullerenol was shown to have a strong antioxidative capability. The present study examined the role of fullerenol as a potential antioxidative protector for doxorubicin-induced oxidative stress in the blood of rats through an investigation of the activity of glutathione-dependent enzymes (glutathione-S-transferase and glutathione peroxidase). It also assessed the influence of fullerenol on the number of blood cells (leukocytes and erythrocytes) as well as on the content of hemoglobin after a single dose administration of doxorubicin. Experiments were performed on six groups of adult male Wistar rats, each group containing eight individuals. Doxorubicin was administrated i.v. (tail vein) in a single dose of 10 mg/kg. Fullerenol C(60)(OH)(24) was administrated to the treated animals i.p. (in doses 50, 100, 200 mg/kg) 30 min before the dosing with doxorubicin. The control group animals were given saline (1 ml/kg; i.p.). One group of animals was treated only with fullerenol (100 mg/kg i.p.). The animals were sacrificed 2 and 14 days after the treatment. Each experiment was repeated twice. The results may indicate that fullerenol induces a decrease in the antioxidative capacity of erythrocytes in oxidative stress conditions, whereas, without doxorubicin, the application of fullerenol did not induce any changes in the enzyme activity of erythrocytes. The results of GST activity might indicate that 50 mg/kg are not sufficient to protect from doxorubicin toxicity, while 200 mg/kg might be toxic for animals, judging from the increase in GST activity.

Antibiotics as additives in animal feedstuffs are forbidden in many countries in the world, but they are still abused. A micellar electrokinetic capillary chromatography method was performed at 25 °C and 30 kV (under pressure 15 mbar) using 25 mmol dm–3 phosphate buffer (pH = 8.0) containing 70 mmol dm–3 sodium dodecysulfate (SDS) and 10 % (volume fraction) methanol as the background electrolyte for separation and determination of amoxicillin, ampicillin, sulfamethoxazole, and sulfacetamide. UV detection was set at 210 nm. The method was validated and antibiotics were quantitatively determined as additives in spiked animal feedstuffs. Results were compared with a new HPLC method for the evaluation of four antibiotics in real samples. Both developed methods can be used for routine analysis of amoxicillin, ampicillin, sulfamethoxazole, and sulfacetamide as additives in animal feedstuffs.

Anthracycline antibiotics are among the most effective and commonly used anticancer drugs. Unfortunately, their clinical use is restricted by dose-dependent toxicity. Doxorubicin is an anthracycline antibiotic and cytotoxic (antineoplastic) agent. It is commonly used against ovarian, breast, lung, uterine and cervical cancers, Hodgkin's disease, soft tissue and primary bone sarcomas, as well against in several other cancer types. It has been shown that free radicals are involved in doxorubicin-induced toxicity. Doxorubicin causes the generation of free radicals and the induction of oxidative stress, associated with cellular injury. This review illustrates recent applications of different natural products, drugs, drug delivery systems, and approaches for protection against doxorubicin-induced toxicity (2006-present).

Epidemiological and experimental studies suggest that eating habits and a sedentary lifestyle play a critical role in the incidence of colon carcinoma. In order to investigate the effects of high-fat mixed-lipid (HFML) diet in conjunction with long-term swimming, the antioxidant capacity of skeletal and cardiac muscles were observed in rats with 1,2-dimethylhydrazine (DMH)-induced colon carcinoma. Male Wistar rats were randomly divided into one control group and four cancer groups: sedentary and swimming groups fed low fat corn oil diet and sedentary and swimming groups, fed a HFML diet. After 6 months of swimming, rats were sacrificed and the blood, cardiac and soleus muscle were taken for analysis. Serum cholesterol, triglyceride and glucose concentrations were measured and the activity of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase as well as levels of malondialdehyde and glutathione were determined. The results showed that endurance swimming prevented lipid peroxidation in the soleus muscle of HFML diet rats due to elevated activities of antioxidant enzymes. On the other hand, increased lipid peroxidation in the hearts of all cancer groups indicated that DMH-induced colon carcinoma impaired the antioxidant status of the heart. This failure in heart tissue indicated that enhanced antioxidant capacity after regular physical activity is not sufficient to offset oxidative stress caused by DMH-induced colon carcinoma.

The effects of fullerenol C60(OH)24 (Frl) at doses of 25, 50, and 100mg/kg/week (for a time-span of 3 weeks) on heart and liver tissue after doxorubicin (Dox)-induced toxicity in rats with colorectal cancer were investigated. In the present study, we used an in vivo Wistar male rat model to explore whether Frl could protect against Dox-induced (1.5mg/kg/week for 3 weeks) chronic cardio- and hepato- toxicity and compared the effect with a well-known antioxidant, vitamin C (100mg/kg/week for 3 weeks). According to macroscopic, microscopic, hematological, biochemical, physiological, pharmacological, and pharmacokinetic results, we confirmed that, at all examined doses, Frl exhibits a protective influence on the heart and liver tissue against chronic toxicity induced by Dox.

A method is described for quantitating caffeine, theobromine, theophylline, paracetamol, propyphenazone, acetylsalicylic acid, salicylic acid, and codeine phosphate in corresponding real samples of food, beverages, natural products, pharmaceuticals, and cosmetic preparations by micellar electrokinetic capillary chromatography. The separation is carried out at 25 degrees C and 25 kV, using a 20 mM phosphate buffer (pH 9.0), 80 mM sodium dodecyl sulfate, and 7.5% (v/v) acetonitrile. UV detection is at 210 nm. The method is shown to be specific, accurate (recoveries over the range 98.9-101.2%), linear over the tested range (correlation coefficients>or=0.9993), and precise (relative standard deviation below 2.1%). The method is applied for the quantitative analysis of these compounds in different foods, beverages, natural products, pharmaceuticals, and cosmetic products.

The aim of this study was to investigate the potential protective role of fullerenol C60(OH)24 on doxorubicin-induced liver toxicity using in vivo (female Sprague-Dawley rats) and in vitro (human hepatocellular carcinoma - HepG2; colorectal adenocarcinoma cell lines - Caco-2) approaches. The first (healthy control) and second (control with chemically induced mammary carcinomas) group received saline only. The third, fourth and fifth group (all with breast cancer) were injected (i.p.) with a single dose of doxorubicin (8mg/kg), doxorubicin/fullerenol (100mg/kg of fullerenol 30min before administration of 8mg/kg doxorubicin) and fullerenol (100mg/kg), respectively. Two days after treatment, the rats were sacrificed. Results showed that treatment with doxorubicin alone caused significant changes in the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and alpha-hydroxybutyrate dehydrogenase (alpha-HBDH), as well as in the levels of malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GSH-Px), total antioxidant status (TAS), glutathione reductase (GR), catalase (CAT) and superoxide dismutase (SOD) in the liver tissue. These effects were significantly reduced for all investigated parameters by pre-treatment with fullerenol but not for the MDA and GSH level. The HepG2 and Caco-2 cell lines were continuously treated with fullerenol for 12h, 24h, 48h and 96h at concentrations of 10microg/mL and 44microg/mL. With the aim of evaluating the modulating activity of fullerenol on doxorubicin-induced hepatotoxicity, the cell lines were simultaneously treated with doxorubicin (1microm; 5microm) and fullerenol (10microg/mL; 44microg/mL) in different combinations. When the cells are treated with 5microm doxorubicin along with the fullerenol, we can see a significant improvement of the cell capability during the entire time-line. We can conclude that fullerenol has cytotoxic effects on HepG2 by itself, but when the oxidative stress is too high the cytotoxic effects of fullerenol are overcome by its protective role as a strong antioxidant compound.

Oxidative stress has an important role in the pathogenesis of doxorubicin (DOX)-induced nephrotoxicity. The aim of this study was to investigate the nephroprotective effects of fullerenol (FLR), an antioxidant agent, on DOX-induced nephrotoxicity. The investigation was carried out on adult female Sprague Dawley outbred rats with chemically induced breast cancer (1-methyl-1-nitrosourea; 50 mg/kg; ip). Rats were divided into the following groups: control healthy, control cancer, DOX alone (8 mg/kg, ip, cancer), DOX plus FLR as a pre-treatment (8 mg/kg and 100 mg/kg, respectively, ip, cancer), and FLR alone (100 mg/kg, ip, cancer). At the end of the 2nd day after drug administration, blood and kidney tissues were taken for analysis. The activity of lactate dehydrogenase and alpha-hydroxybutyrate dehydrogenase as serum enzymes, as well as level of malondialdehyde, glutathione, glutathione peroxidase, glutathione reductases, catalase and superoxide dismutase, were determined. DOX caused nephrotoxicity, but FLR pre-treatment prevented oxidative stress, lipid peroxidation and the disbalance of GSH/GSSG levels in kidney tissue caused by DOX. Our results confirm satisfactory nephroprotective efficacy of FLR in the acute phase of toxicity and encourage further studies regarding its use as a potential nephroprotector.

Micellar electrokinetic capillary chromatography (MEKC) has become a popular mode among the several capillary electro-migration techniques. Most drug analysis can be performed by using MEKC because of its wide applicability. Separation of very complex mixtures, determination of drugs in the biological materials, etc., can be successfully achieved by MEKC. This review surveys typical applications of MEKC analysis. Recent advances in MEKC, especially with solid-phase extraction and large-volume sample stacking, are described. Modes of electrokinetic chromatography including MEKC, a separation theory of MEKC, environmental friendly analysis, and selectivity manipulation in MEKC are also briefly mentioned. Micelama elektrokinetička kapilarna hromatografija (MEKC) postala je najpopularnija kapilarna elektromigraciona metoda. Na osnovu veoma široke upotrebe metode, većina analiza lekova moguća je uz MEKC. Separacija veoma kompleksnih smeša, određivanje lekova u biološkom materijalu, i analize drugih uzoraka, mogu biti veoma uspešno izvedene upotrebom MEKC tehnike. U okviru ovog preglednog rada prikazana je aplikacija tipičnih MEKC metoda. Noviji pristupi u kombinaciji sa čvrsto-faznom ekstrakcijom i visoko-volumskim injektovanjem su takođe opisani. Teorijski i ekološki pristup, kao i prednosti i nedostatci same metode, prikazani su teorijski i kroz praktične primere.

A novel and simple method has been developed for the determination of doxycycline (DOX) in biological fluids. The method is based on SPE, large-volume sample stacking (LVSS) and MEKC with UV-DAD detection. Six SPE cartridges have been used in investigation for sample clean up and pre-concentration (Supelco (R) LC-8, LC-18, LC-SCX, and LC-WCX, as well as Strata (TM)-X and X-C). DOX was determined on a 56 cm. (effective length 50 cm) x 50 mu m id fused-silica capillary. The BGE was 20 mM borate buffer, pH 9.3, containing 80 mM SDS and 7.5% v/v of methanol (30 s x 50 mbar), and the temperature and voltage were 25 degrees C and 30 kV, respectively. The analytical wavelength was set at 210 nm. Under optimized conditions it is possible to determine DOX in human serum, urine, semen, tears and saliva with recovery of 97.5% (RSD 2.5%). The method was shown to be sensitive (LOD is 1 mu g/L) and precise (intra-day RSD 0.2 and 2.4%; inter-days 0.4 and 3.5% for migration time and peak area, respectively). Results for developed SPE-LVSS-MEKC were compared with LVSS-MEKC method with direct sample injection. The new LVSS-MEKC method is presented as a useful technique for rapid determination without extraction procedure of DOX in human urine and serum, using 80mM of SDS, 10% v/v of methanol and 40 mM borate buffer (pH 9.3; 30 s x 50 mbar; 25 degrees C; 30 kV; 350 nm), but not for the other biological fluids, according to lower sensitivity of the method and because of the sample composition.

Micellar electrokinetic capillary chromatography and reverse-phase liquid chromatography methods were developed in order to perform robustness testing to determine the caffeine content in beverages. Both methods were fully validated and two different robustness approaches were applied. One-variable-at-a-time (OVAT) approach at eleven levels (0; +/-1; +/-2; +/-3; +/-4; +/-5 units) was carried out and compared with multi-variable-at-a-time (MVAT) approach at three levels (+/-1 unit per investigated parameter). Four analysts in two laboratories on two capillary electrophoresis and two RPLC equipments have tested the samples. Robustness was statistically analyzed using peak area, migration or retention time, symmetry, and resolution of caffeine and sulfacetamide as internal standard, and presented as R.S.D. values. The RPLC method was found to be more sensitive than the MEKC method. Both methods showed acceptable robustness level for OVAT approach, whilst MEKC method was more robust when the determination of real samples coming from different beverages was based on the MVAT approach.

A high-performance liquid chromatography (HPLC) method for the quantitation of doxycycline in bulk, tablets, and capsules after storage at -20, 5, 25, 40, 50, 60, and 70 degrees C, has been developed and validated. The samples are eluted from a micro-Bondapak C8 column (4.6x150-mm, i.d., 5-microm particle size) at 27 degrees C, with a mobile phase of acetonitrile-water-THF (29.5:70:0.5, v/v/v), adjusted to pH 2.5 with 1.0M HCl. The flow rate is 1.0 mL/min and detection by UV is at 350 nm. The stability of doxycycline in bulk and in pharmaceuticals is checked over 90 days. Doxycycline shows thermo-degradation after exposure to high temperature; tablets are more stable than capsules. The shelf lives (t90%) are determined to be 1.00, 2.84, and 5.26 years in bulk, capsules, and tablets, respectively, at 25 degrees C. Metacycline and 6-epidoxycyline are identified as degradation products at high temperatures. Amounts of doxycycline, metacycline, and 6-epidoxycycline in all samples are determined by HPLC, and the results compare with those from micellar electrokinetic capillary chromatography. After 90 days, metacycline and 6-epidoxycyline are almost equal in test samples from standard bulk form, tablets, and capsules. It is 27.8+/-0.3%, 13.7+/-0.1%, and 18.8+/-0.2%, respectively.

Flavonoids represent an important bioactive component in Achillea millefolium. The comparison of the most commonly used analytical methods for the identification and quantification of flavonoids, capillary electrophoresis (CE) and high performance liquid chromatography (HPLC), is presented. The methods were optimized and validated. Using a 20 mM borate buffer with 30% (v/v) of methanol (pH 9.3) in the CE analysis and a gradient elution with water-acetonitrile mobile phase in the HPLC analysis, sufficient separation of the analytes was achieved. A relatively high injection volume in the CE analysis (30 mbar x 30s) enabled low limit of detection (LOD) (0.3-0.7 mg/L). Repeatability of both methods was acceptable (relative standard deviation of peak area were

A rapid and selective high-performance liquid chromatographic (HPLC) method is developed for the separation and determination of caffeine, theobromine, and theophylline. The chromatography is performed on a Zorbax Eclipse XDB-C8 column (4.6x150 mm i.d., 5-microm particle size) at 25 degrees C, with a mobile phase of water-THF (0.1% THF in water, pH 8)-acetonitrile (90:10, v/v). The flow rate is 0.8 mL/min, and detection is by UV at 273 nm. This method permits the simultaneous determination of caffeine, theobromine, and theophylline in food, drinks, and herbal products with detection limits of 0.07-0.2 mg/L and recoveries of 100.20-100.42%. Correlation coefficients, for the calibration curves in the linear range of 0.2-100 mg/L, are greater than 0.9999 for all compounds. The within- and between-day precision is determined for both retention times and peak area. The data suggests that the proposed HPLC method can be used for routine quality control of food, drinks, and herbal products.