Development and validation of a method for the simultaneous determination of 20 organophosphorus pesticide residues in corn by accelerated solvent extraction and gas chromatography with nitrogen phosphorus detection

The method for simultaneous determination of 20 organophosphorus pesticide residues in corn samples has been developed and validated. For the extraction of organophosporus pesticide residues from the samples, the accelerated solvent technique with the mixture of dichloromethane: acetone (1:1, V/V) was used. Clean up was done using liquid – liquid extraction with n – hexane, followed by solid phase extraction on primary secondary amine adsorbent, and elution with the mixture of acetone: toluene (65:35). The determination of the pesticides was carried out by gas chromatography with nitrogen phosphorus detection. Separation and quantitative determination of the analytes were performed on a fused silica capillary ZB-35 column (30 m x 0.25 mm i.d. x 0.25 μm, Phenomenex). The recovery was investigated in blank corn samples fortified with mevinphos, diazinon, dimethoate, bromofos-methyl, chlorfenvinphos, fenamiphos, ethion and phosalone at 5 ng/g, 10 ng/g, 15 ng/g , 20 ng/g and 25 ng/g, respectively and with methacrifos, phorate, etrimfos, parathion-methyl, pirimiphos - methyl, fenitrothion, chlorpyrifos, malathion, parathion, bromofos-ethyl, phosmet and azinphos-methyl at 10 ng/g, 20 ng/g, 30 ng/g, 40 ng/g and 50 ng/g, respectively. The recovery ranged from 76.0% to 112.0%. Repeatability expressed as relative standard deviation (RSD) was less than 8.2%. Linearity expressed as correlation coefficient (R2) ranged from 0.9935 to 0.9996. Measurement uncertainty (Ux) was lower than 14.2% for all tested pesticides. The limits of quantification (LOQ) were bellow 5 ng/g for all tested pesticides. The satisfactory Z-score results of international proficiency tests confirm good analytical performances of the developed method. Keywords: Organophosporus Pesticide Residues, Gas Chromatography, Accelerated Solvent Extraction, Solid Phase Extractio

Determination of some volatile compounds in fruit spirits produced from grapes (Vitis Vinifera L.) and plums (Prunus domestica L.) cultivars

Fruit spirits contain a large array of volatile compounds among which the important role from toxicological aspect besides ethanol has methanol, aliphatic esters and fusel alcohols. This study evaluates the content of ethanol, ethyl acetate, methanol, isopropyl alcohol (2-propanol), n-propyl alcohol (propan-l-ol), isobutyl alcohol (2-methylpropan-1-ol), n-butyl alcohol (1-butanol), isoamyl alcohol (3-methyl-1-butanol) and n-amyl alcohol (pentan-1-ol) in different grapes and plum brandies industrially produced at Republic of Macedonia. Gas chromatography (GC) with flame ionization detection (FID) was applied for the characterization of all investigated volatile compounds. The obtained results revealed that the highest methanol content was present in the samples of plum brandy, which is mainly due to the higher content of pectin in the raw material. The most important higher alcohols of grape and plum brandies were found to be: n-propyl alcohol, isobutyl alcohol and isoamyl alcohol. In all the analyzed samples of grape and plum brandies, the most abundant was isoamyl alcohol which content ranged from 50.3 to 290.7 mg/100 mL a.a. Comparing the results with the data from the literature, it can be concluded that the concentrations of all investigated volatile compounds in the samples of grape and plum brandies are commonly acceptable. Keywords: Fruit Spirits, Gas Chromatography (GC), Methanol, Ethyl Acetate, Fusel Alcohol

ASSESSMENT OF RADIOLOGICAL HAZARD FOR VARIOUS FOOD COMMONLY USED IN REPUBLIC OF NORTH MACEDONIA

Consuming food containing radionuclides is particularly dangerous. If anyone ingests or inhales a radioactive particle, it continues to irradiate the body as long as it remains radioactive and stays in the body. However, studies on the radioactivity of consumable foods assume importance as it is necessary to estimate the ingestion dose to the public. Due to all this, the focus of this research was on determining the activity concentrations of 226Ra, 40K and 232Th. Forty-nine samples in three categories of vegetables, cereals (rice, wheat, corn), and milk, were collected from local markets (city of Skopje) in the Republic of North Macedonia and they were analyzed by using high-purity germanium (HPGe) detector to assess natural and artificial radioactivity. The average activity concentrations of 226Ra, 40K and 232Th of the tested samples were 2.85±1.15, 2.48±0.85, and 80.64±5.45 Bq kg-1, respectively. No artificial radionuclide was found in any of these samples. The average value of the radium equivalent activity in all samples was 12.56 Bq kg-1, which was less than the maximum permitted value of 370 Bq kg-1. The values ​​of the external hazard indices for vegetables, cereals and milk samples vary with an average value of 0.11, which is less than one in all samples indicating the non-harmfulness of the samples. The mean activity concentrations of 226Ra, 40K and 232Th (Bq kg-1) in the samples were used to calculate the absorbed dose rate whose mean value for all food samples was 6.16 Bq kg-1. It was determined that the measured values are within the globally accepted values, i.e., they are quite lower than the data in literature. These data would be useful to establish a baseline for natural radioactivity concentrations in food products consumed in the Republic of North Macedonia

DETERMINATION OF RADIONUCLIDE CONCENTRATION IN MILK SAMPLES CONSUMED IN REPUBLIC OF NORTH MACEDONIA AND POPULATION DOSE RATE ESTIMATES

Milk is one of the most important food products in the human diet and contains all the macronutrients, that is, proteins, carbohydrates, fat, vitamins (A, D and B groups) and trace elements, especially calcium, phosphorus, magnesium, zinc and selenium. Milk contamination is largely due to the grazing of animals on contaminated grass and drinking water. Grass is a direct source or route of radionuclides to animals and humans through the consumption of meat and milk. One of the important tasks of the veterinary activity is veterinary-sanitary supervision of the production and sale of milk and dairy products, whose main goal is the provision of biologically good milk and dairy products from healthy animals.The purpose of this study was to determine the activity concentrations of 226Ra, 232Th 40K and 137Cs in milk samples most commonly used in daily consumption in the Republic of North Macedonia and based on the results, the risk of radiation to the population can be estimated. An instrument - gamma spectrometer (Canberra Packard) with a high purity germanium detector and GENIE 2000 program was used for measurement of the samples.On the basis of the performed tests, the mean activity concentrations of 226Ra, 232Th, and 40K were 1.76 ± 0.23; 1.05 ± 1.00; 31.9 ± 5.07 (Bq·kg-1), respectively. 40K has the highest value compared to other radionuclides due to the process of transfer from soil to grass and from grass and water to milk.The activity of 137Cs is below the detection limit for all tested milk types. This shows that there is no risk of radiation to the population, i.e., the safety limits are not exceeded, which points out the insignificant threat of radiation arising from radionuclides that are naturally or artificially present in the tested milk, and that reach humans through the food chain

Pharmacoeconomic analysis of parenteral therapy consumption in hospital pharmacy at Clinical Hospital – Stip

Improper management of drugs and medical devices is a complex problem at all health care levels. A study conducted in 2016 in which were included 35 hospitals in Poland (Religioni, 2016), was the basis for developing a drug management system. This study showed that most managers, including pharmacists (62.86%) have no knowledge for the principles of drug management optimization. Only 20% of them used pharmacoeconomic analysis and 25% did not use any analysis. 77% of the respondents selected the drugs based on the lowest price

Goodpasture Syndrome Diagnosed One Year And A Half after the Appearance of the First Symptoms (Case Report)

BACKGROUND: Goodpasture's syndrome was originally described as an association of alveolar haemorrhage and glomerulonephritis. It occurs when the immune system attacks and destroys healthy body tissue.AIM: We are presenting a patient with a clinical picture of pulmonary haemorrhage and glomerulonephritis, which is diagnosed by renal biopsy.CASE PRESENTATION: His illness began a year and a half before being diagnosed. In that period he had occasional exacerbations. He was received at our Clinic in extremely serious condition, and after stabilisation of his medical condition, there was made a biopsy of the kidney. The p-ANCA was 8.93 U/ml (neg < 3, poz > 5 U/ml). Histopathological diagnosis of biopsy of the kidney was: Glomerulonephritis extra capillaries focalis, segmentalis et globalis. Based on this he was diagnosed with Goodpasture's syndrome. He received corticosteroid therapy and cyclophosphamide, with good response to treatment, and he is currently in a stable condition, receiving only corticosteroid therapy.CONCLUSION: Goodpasture’s syndrome is a severe illness caused by the formation of antibodies to the glomerular basement membrane and alveolus with consequential damage to renal and pulmonary function. With current therapy, long-term survival is more than 50%

With food to health : proceedings of the 10th International scientific and professional conference

Proceedings contains 13 original scientific papers, 10 professional papers and 2 review papers which were presented at "10th International Scientific and Professional Conference WITH FOOD TO HEALTH", organised in following sections: Nutrition, Dietetics and diet therapy, Functional food and food supplemnents, Food safety, Food analysis, Production of safe food and food with added nutritional value

Distribution of the total arsenic content in drinking water obtained from different water sources in the Republic of Macedonia

The present study investigates the total arsenic (As) content in the samples of drinking water in the Republic of Macedonia, which is obtained from different water sources, such as: springs, surface accumulations, underground accumulations and drilled wells. From January 2013 to December 2013, a total of 780 samples obtained from the public water supply systems at 35 measurement points distributed throughout the whole territory of the Republic of Macedonia were analyzed on the total As content. A flow injection atomic absorption spectrometry (FIAS) was employed for the determination of the total As content after wet digestion of the samples with nitric acid (67%, W/V) and hydrogen peroxide (30%, V/V). The results of the study revealed that in 96.7% of the tested samples, As content was below established maximum allowable concentration (MAC) of 10 μg/L. As concentrations up to 26.4 μg/L were found in the samples of drinking water that comes from the water sources located in the vicinity of Kozhuf Mountain, which is due to the mineral composition of the mountain body rich with As containing minerals: lorandite, orpiment, realgar, arsenopyrite etc. Higher As concentrations (5.47 μg/L – 26.6 μg/L) were also found in the samples of drinking water obtained from the water supply system of the towns from the Dojran Municipality which are located in the vicinity of thermal-mineral area of Mala Boshka – Toplec. It can be concluded that the presence of total As in the potable water in the Republic of Macedonia comes only from natural sources. Keywords: Arsenic (As), Drinking Water, Flow Injection Atomic Absorption Spectrometry (FIAS), Maximum Allowable Concentration (MAC

Development and validation of a method for the simultaneous determination of 20 organophosphorus pesticide residues in corn by accelerated solvent extraction and gas chromatography with nitrogen phosphorus detection

The method for simultaneous determination of 20 organophosphorus pesticide residues in corn samples has been developed and validated. For the extraction of organophosporus pesticide residues from the samples, the accelerated solvent technique with the mixture of dichloromethane: acetone (1:1, V/V) was used. Clean up was done using liquid – liquid extraction with n – hexane, followed by solid phase extraction on primary secondary amine adsorbent, and elution with the mixture of acetone: toluene (65:35). The determination of the pesticides was carried out by gas chromatography with nitrogen phosphorus detection. Separation and quantitative determination of the analytes were performed on a fused silica capillary ZB-35 column (30 m x 0.25 mm i.d. x 0.25 μm, Phenomenex). The recovery was investigated in blank corn samples fortified with mevinphos, diazinon, dimethoate, bromofos-methyl, chlorfenvinphos, fenamiphos, ethion and phosalone at 5 ng/g, 10 ng/g, 15 ng/g , 20 ng/g and 25 ng/g, respectively and with methacrifos, phorate, etrimfos, parathion-methyl, pirimiphos - methyl, fenitrothion, chlorpyrifos, malathion, parathion, bromofos-ethyl, phosmet and azinphos-methyl at 10 ng/g, 20 ng/g, 30 ng/g, 40 ng/g and 50 ng/g, respectively. The recovery ranged from 76.0% to 112.0%. Repeatability expressed as relative standard deviation (RSD) was less than 8.2%. Linearity expressed as correlation coefficient (R2) ranged from 0.9935 to 0.9996. Measurement uncertainty (Ux) was lower than 14.2% for all tested pesticides. The limits of quantification (LOQ) were bellow 5 ng/g for all tested pesticides. The satisfactory Z-score results of international proficiency tests confirm good analytical performances of the developed method. Keywords: Organophosporus Pesticide Residues, Gas Chromatography, Accelerated Solvent Extraction, Solid Phase Extractio

Collaborative learning in Faculty of Medical Sciences - Stip: Group work and study teams

Students learn best when they are actively involved in the learning process. Researchers report that, regardless of the subject matter, students working in small groups tend to learn more of what is taught and retain it longer than when the same content is presented in other instructional formats. Students who work in collaborative groups also appear more satisfied with their classes. Various names have been given to this form of teaching, and there are some distinctions among these: cooperative learning, collaborative learning, collective learning, learning communities, peer teaching, peer learning, reciprocal learning, team learning, study circles, study groups and work groups. But all in all, there are three general types of group work: informal learning groups, formal learning groups, and study teams (adapted from Johnson and Smith, 1991). Informal learning groups are ad hoc temporary clustering of students within a single class session. Formal learning groups are teams established to complete a specific task. Usually, students work together until the task is finished, and their project is graded. Study teams are long-term groups (usually existing over the course of a semester) with stable membership whose primary responsibility is to provide members with support, encouragement, and assistance in completing course requirements and assignments. The larger the class and the more complex the subject matter, the more valuable study teams can be. Key words: inclusion, learning, teaching, education