High Antimicrobial Efficacy, Antioxidant Activity, and a Novel Approach to Phytochemical Analysis of Bioactive Polyphenols in Extracts from Leaves of Pyrus communis and Pyrus pyrifolia Collected During One Vegetative Season.

Dried leaf samples of Pyrus communis L. var. 'Conference' and Pyrus pyrifolia Burm. f. (Nakai) var. 'Shinseiki' were subjected to the successful extraction procedures using various solvents, followed by filtering and/or drying liquid plant preparations under reduced pressure. As a result of this, for each Pyrus leaf sample examined, four dried residues were obtained, including methanolic (EA), ethyl acetate (EC), water (EB), and the residue obtained from aqueous solution (ED). Antiradical activity of these preparations was measured using the ABTS+• assay, and antimicrobial activity was examined using various strains of bacteria and yeasts. The highest antiradical activity was observed for EC from leaves of P. communis var. 'Conference' collected in May, but the highest average antibacterial activity was noted for EC residues from P. pyrifolia var. 'Shinseiki' collected in May. Antibacterial activity positively correlated with concentration of hydroquinone in extracts. No antifungal activity was observed for any extract. In addition, qualitative and quantitative analyses of active polyphenolic components in extracts from Pyrus were performed. Hydroquinone and hydroxycinnamic acid derivatives were analyzed using a new optimized method comprising reversed-phase high-performance liquid chromatography (RP-LC) coupled with simultaneous photodiode-array and fluorescence detection.

Antimicrobial and Antiradical Activity of Extracts Obtained from Leaves of Five Species of the Genus Bergenia: Identification of Antimicrobial Compounds.

An important focus of modern medicine is the search for new substances and strategies to combat infectious diseases, which present an increasing threat due to the growth of bacterial resistance to antibiotics. Another problem concerns free radicals, which in excess can cause several serious diseases. An alternative to chemical synthesis of antimicrobial and antiradical compounds is to find active substances in plant raw materials. We prepared extracts from leaves of five species of the genus Bergenia: B. purpurascens, B. cordifolia, B. ligulata, B. crassifolia, and B. ciliata. Antimicrobial and antiradical features of extracts and raw materials were assessed, and the quantities of phenolic compounds were determined. We also evaluated, using high-performance liquid chromatography, the amounts of arbutin and hydroquinone, compounds related to antimicrobial activity of these raw materials. The strongest antiradical properties were shown by leaves of B. crassifolia and B. cordifolia, the lowest by leaves of B. ciliata. The antiradical activity of extracts showed a strong positive correlation with the amount of phenols. All raw materials have significant antimicrobial properties. Among them, the ethyl acetate extracts were the most active. Antimicrobial activity very weakly correlated with the amount of arbutin, but correlated very strongly with the contents of both hydroquinone and phenolic compounds. Additional experiments using artificially prepared mixtures of phenolic compounds and hydroquinone allowed us to conclude that the most active antimicrobial substance is hydroquinone.

ANTIRADICAL AND ANTIMICROBIAL ACTIVITY OF PHENOLIC FRACTIONS OBTAINED FROM HONEYS.

Honey is a natural product consisting of multiple components which determine its dietary and medicinal properties. In this work there were studied methanol fractions obtained from seven honeys from Lower Silesia (Poland) collected in different seasons of three successive years. Melissopalynologic studies revealed that two of them were polyfloral, and five were classified as monofloral (two buckwheat and three rapes). The amount of phenolic compounds in honeys varied from 0.09 to 0.38 mg per g of honey. Honeys harvested in 2010 were the richest in phenolic compounds and especially rich was buckwheat honey, comparing to 2011- 2012. Determination of antioxidant potential with the DPPH radical revealed that the strongest antiradical activity was exhibited by extracts obtained from polyfloral (1.22 TAU(515/mg)) and buckwheat (1.06 TAU(515lmg)) honeys, while the highest number of antiradical units was observed for rape honey (3.64 TAU(515/g)). Polyphenolic fractions exhibited various bactericidal activities against Klebsiella pneumoniae and Staphylococcus aureus and weak or no activity was observed against Pseudomonas aeruginosa.

Analysis of Polyphenolic Compounds in Extracts from Leaves of Some Malus domestica Cultivars: Antiradical and Antimicrobial Analysis of These Extracts.

In this study, methanol, ethyl acetate, water extracts, and precipitate were obtained from leaves of Malus domestica cultivars: Golden delicious, Jonagold, Elstar, Ligol, and Mutsu. Antiradical activity of these extracts was measured using the ABTS+∙ radical, and antimicrobial activity was measured with the disk-diffusion method. Phenolic compounds were measured with the colorimetric method and identified with high performance liquid chromatography (HPLC). The highest antiradical activity was observed for the Jonagold variety, and in particular strong activity was noted for ethyl acetate extracts. Antimicrobial activity was observed against strains of Staphylococcus aureus, Enterococcus faecalis, and the fungus Candida glabrata. Particularly susceptible to the extracts activity appeared to be Staphylococcus aureus, but the growth of Candida glabrata was inhibited in the presence of ethyl acetate extracts. With the HPLC method we identified a high amount of phloridzin (above 500 mg per g of ethyl acetate extracts), lower amounts of hyperoside, isoquercitrin, and quercitrin, and traces of p-hydroxybenzoic and chlorogenic acids. The contribution of phloridzin to antiradical activity of methanol and ethyl acetate extracts was very high (above 90%). In water extract the contribution of phloridzin was between 38.9 and 55.2%, chlorogenic acid 22.7 and 36.1%, and hyperoside 12.2 and 13.3%.

[Selected ethical problems in neonatology -- opinions of physicians and nurses based on questionnaire study]. / Wybrane problemy etyczne w neonatologii -- poglady lekarzy i pielegniarek na podstawie badan ankietowych.

UNLABELLED: AIM OF THIS PAPER: To present the opinions of doctors and nurses on the limitations of resuscitation and treatment of extremely premature newborns. MATERIAL AND METHODS: Anonymous questionnaire studies were carried out in 342 doctors and 1194 nurses from 6 provinces of Poland. The authors compared the answers of doctors and nurses as well as the answers form different provinces. The results were processed using the Chi2 test, with the significance level p<0.05. RESULTS: The will to resuscitate the neonate, regardless of its birth weight was declared by 29% of the physicians and 49% of the nurses, regardless of the gestational age - by 21% of the physicians and 47% of the nurses. Resuscitation of an extremely immature, asphyctic newborn was declared by 71% of the physicians and 59% of the nurses. Limitation of therapy after diagnosing severe intracranial hemorrhage is declared by 67% of the physicians and 45% of the nurses. 37% of the doctors and 30% of the nurses would comply with parents' will when deciding about resuscitation. 44% of the physicians and 31% of the nurses declare taking parents' decision into account in the matter of abandoning resuscitation. CONCLUSIONS: 1. There is a higher percentage of persons convinced about the necessity of resuscitation of every newborn, regardless of its maturity, among the nurses than among the doctors. 2. Among the nurses there are more persons, who are sceptical about saving the extremely premature newborns born with asphyxia, whereas among the doctors there are more persons inclined to stop therapy in case of a severe intracranial hemorrhage. 3. The most controversial are problems concerning the consideration of parents' will in decision about whether to continue or abandon resuscitation, but physicians are more apt to regard parents' will in resuscitation in some situations. 4. The analysis of the questionnaire points to the need for deeper knowledge of the present mortality rates of the extremely immature newborns and further development of the surviving ones among the physicians and nurses.

[An attempt to evaluate the dependence between the concentration of fT3, fT4 and TSH in blood serum and the chosen perinatal risk factors in prematurity born babies with Respiratory Distress Syndrome]. / Próba oceny zaleznosci pomiedzy stezeniem fT3, fT4 i TSH w surowicy krwi a wybranymi czynnikami ryzyka okoloporodowego u noworodków przedwczesnie urodzonych z zespolem zaburzen oddychania.

The aim of this work was to evaluate the influence of chosen perinatal risk factors on the level of fT3, fT4 and TSH in prematurely born babies with RDS. The enquiry included 100 new-born babies treated of prematurity and RDS in the Department of Neonatology and Intensive Care of the Specialist Hospital in Gdansk. The analysis of the results revealed that the levels of fT3 and fT4 in blood serum of prematurely born babies show a clear dependence from gestational age, the babies' wellbeing directly after birth, FiO2 and the grade of respiratory insufficiency. It also revealed long-lasting features of hypothyreosis in new-borns receiving respiratory support for a longer period of time.