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1.
Animals (Basel) ; 13(21)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37958100

RESUMO

Observation and behavioral analysis of animals can be one of the factors taken into consideration when assessing the welfare of animals kept in artificially created breeding conditions. Disturbed welfare and prolonged exposure to stress can lead to the emergence of abnormal behaviors, including reproductive issues. The aim of this study was to examine the mating behavior of male American mink, with regard to the duration of mating and any potential differences with regard to time of day, mating period, number of mating attempts, and time spent with the female. The study material consisted of 12 one-year-old male American minks with pearl coloring and 60 two-year-old females. Observations were conducted using images captured using externally mounted cameras. The video material capturing the activity of males and females during the mating period was analyzed using the Behawior program. The obtained results indicate the presence of individual differences in copulation duration. It was observed that the copulation time increases with successive days of the breeding season and with number of copulations. It was also observed that a longer time spent with the female to initiate copulation, and behaviors such as rubbing or sniffing the female, were associated with a shorter copulation time. The above-mentioned studies provide specific guidelines regarding the management of matings on the farm, demonstrating the feasibility of conducting matings both in the hours before and after noon.

2.
Molecules ; 28(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36771061

RESUMO

Protozoa, in both humans and animals, are one of the leading causes of disease. International programmes introduced in many countries have helped reduce the incidence of disease. However, it has recently become increasingly difficult to achieve the goals set for the coming years. One of the main reasons for this, as with other pathogenic organisms, such as bacteria and fungi, is the increasing resistance to current methods of treating and preventing infection. Therefore, new therapies with high efficacy are needed. In the present study, the novel mixtures of essential oils (EOs), clove, garlic, Ceylon cinnamon, and rosemary with organic acids (acetic, propionic, lactic) and metal ions (Cu, Mn, Zn) were tested against five selected model protozoa (Euglena gracilis, Gregarina blattarum, Amoeba proteus, Paramecium caudatum, Pentatrichomonas hominis). The cytotoxicity and potential anticancer activity of the obtained combinations were tested on the human fibroblasts (NHDF) and human cancer cell lines (A549, MCF7, LoVo, HT29). All of the mixtures showed very good antiprotozoal properties. The most efficient were the combination of clove and rosemary essential oils, mixtures of acids, and Mn ions. The LD50 values were in the range of 0.001-0.006% and the LD100 values were 0.002-0.008%. All of the tested mixtures did not show cytotoxicity against normal cells, but did show growth inhibition against cancer cell lines. The most cytotoxic against cancer cells were combinations with cinnamon essential oil. Nevertheless, the proposed combinations containing essential oils, organic acids, and metal ions have high antiprotozoal activity, with low toxicity to healthy human cells.


Assuntos
Antiprotozoários , Óleos Voláteis , Animais , Humanos , Óleos Voláteis/farmacologia , Monoterpenos , Antiprotozoários/farmacologia , Cinnamomum zeylanicum
3.
Animals (Basel) ; 13(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36766332

RESUMO

Ethograms can serve as benchmarks against which abnormal animal behaviour can be identified, and then normal behaviour can be restored by appropriately modifying the environment in which an individual resides. The aim of the present study was to create an ethogram of the reproductive behaviour of American mink kept in farmed conditions. The research material consisted of 12 one-year-old male American mink, pearl coloured, selected randomly from among the varieties of coloured mink on the farm, and 60 two-year-old females. The animals participating in the study were grouped into two breeding sets, each consisting of 30 females and 6 males. Reproductive rituals included chasing the female, grasping her neck with the teeth, marking the local area, mounting the partner, and sniffing the neck, anal and genital areas. The copulation times recorded in this study varied greatly, ranging from several minutes to over two hours. The obtained results indicate that the American mink can express some natural reproductive behaviour in breeding conditions, which may also be an indicator of the welfare of these animals.

4.
Int J Mol Sci ; 22(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34830063

RESUMO

This study describes a method for the modification of polyurethane small-diameter (5 mm) vascular prostheses obtained with the phase inversion method. The modification process involves two steps: the introduction of a linker (acrylic acid) and a peptide (REDV and YIGSR). FTIR and XPS analysis confirmed the process of chemical modification. The obtained prostheses had a porosity of approx. 60%, Young's Modulus in the range of 9-11 MPa, and a water contact angle around 40°. Endothelial (EC) and smooth muscle (SMC) cell co-culture showed that the surfaces modified with peptides increase the adhesion of ECs. At the same time, SMCs adhesion was low both on unmodified and peptide-modified surfaces. Analysis of blood-materials interaction showed high hemocompatibility of obtained materials. The whole blood clotting time assay showed differences in the amount of free hemoglobin present in blood contacted with different materials. It can be concluded that the peptide coating increased the hemocompatibility of the surface by increasing ECs adhesion and, at the same time, decreasing platelet adhesion. When comparing both types of peptide coatings, more promising results were obtained for the surfaces coated with the YISGR than REDV-coated prostheses.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Prótese Vascular , Poliuretanos/química , Poliuretanos/farmacologia , Animais , Materiais Biocompatíveis/síntese química , Coagulação Sanguínea/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Teste de Materiais , Fenômenos Mecânicos , Camundongos , Microscopia Eletrônica de Varredura , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Adesividade Plaquetária/efeitos dos fármacos , Poliuretanos/síntese química , Porosidade , Propriedades de Superfície
5.
Food Res Int ; 130: 108964, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32156399

RESUMO

The food additive carrageenan (E407) (CGN) is a family of sulphated galactans widely used in numerous processed foods, including dairy. There are various indications that CGN may hinder digestive proteolysis. This study sought to link CGN macromolecular characteristics to its implications on digestive proteolysis of whey protein isolate (WPI) in toddlers, adults and seniors. Size exclusion chromatography and dynamic laser scattering reveal commercial CGN samples differ in molecular weight distributions, zeta-potentials and flow behavior of WPI-CGN mixtures. Moreover, κ-CGN, ι-CGN and λ-CGN were found to contain low MW (<200 kDa) fractions at levels of 6.36 ± 2.11% (w/w), 3.64 ± 1.06% (w/w) and 2.08 ± 1.41% (w/w), respectively. In vitro human digestion of WPI-CGN mixtures and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of digesta indicate that CGN alters the breakdown of alpha-lactalbumin, beta-lactoglobulin and lactoferrin differentially in toddlers, adults and seniors digestion conditions. Interestingly, proteomic analyses indicate there is a possible correlation between CGN degree of sulphation and the release of bioactive peptide homologues in the gut lumen. Moreover, these analyses indicate CGN compromises the bioaccessibility of essential amino acids. Altogether, this study shows CGN may attenuate whey digestive proteolysis. This effect should be taken in account by food manufacturers and regulatory agencies in view of the rising levels of exposure to CGN in the human diet.


Assuntos
Envelhecimento , Reatores Biológicos , Carragenina/metabolismo , Aditivos Alimentares , Proteínas do Soro do Leite/metabolismo , Carragenina/química , Cromatografia Líquida/métodos , Humanos , Peptídeos/química , Espectrometria de Massas em Tandem/métodos , Ácido Tricloroacético/química
6.
Appl Biochem Biotechnol ; 184(1): 386-400, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28707051

RESUMO

In view of a commonly known beneficial role and low stability of ascorbic acid, many efforts are constantly undertaken to produce its improved derivatives. This paper presents results on the synthesis of ascorbic acid galactoside using transgalactosylation properties of ß-galactosidase from Kluyveromyces lactis and lactose as a donor of galactosyl moiety. The purpose of this study was to determine the influence of selected factors (concentration and molar ratio of substrates, amount of the enzyme preparation, pH of the solution, presence of different ions) on the course of transgalactosylation reaction. Research has shown that approx. 2.5% dry matter (d.m.; 12.7 g/L) of ascorbic acid galactoside is formed under favourable conditions (50% (w/v) substrates, sodium ascorbate and lactose at the molar ratio of 1.9:1, enzyme dose of 28,600 U/100 g lactose, pH = 7.0). The addition of Mg2+ or K+ ions to the reaction medium caused an increase in the final product content (even up to approx. 3.4% d.m., 17.2 g/L), while Na+ or Mn2+ had an adverse impact on the yield. The gathered data may be valuable for cosmetic or food industry.


Assuntos
Ácido Ascórbico/química , Galactose/metabolismo , Galactosídeos/química , Kluyveromyces/enzimologia , beta-Galactosidase/metabolismo
7.
Food Technol Biotechnol ; 55(2): 258-265, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28867957

RESUMO

Bionic acids are bioactive compounds demonstrating numerous interesting properties. They are widely produced by chemical or enzymatic oxidation of disaccharides. This paper focuses on the galactosyl derivative of gluconic acid as a result of a new method of bionic acid synthesis which utilises the transglycosylation properties of ß-galactosidase and introduces lactose as a substrate. Products obtained in such a process are characterised by different structures (and, potentially, properties) than those resulting from traditional oxidation of disaccharides. The aim of this study is to determine the effect of selected parameters (concentration and ratio of substrates, dose of the enzyme, time, pH, presence of salts) on the course of the reaction carried out with the enzymatic preparation Lactozym, containing ß-galactosidase from Kluyveromyces lactis. Research has shown that increased dry matter content in the baseline solution (up to 50%, by mass per volume) and an addition of NaCl contribute to higher yield. On the other hand, reduced content of the derivative is a result of increased pH from 7.0 to 9.0 and an addition of magnesium and manganese salts. Moreover, exceeding the ß-galactosidase dose over approx. 35 000 U per 100 g of lactose also leads to reduced yield of the process. The most favourable molar ratio of sodium gluconate to lactose is 2.225:0.675. Depending on the conditions of the synthesis, the product concentration ranged between 17.3 and 118.3 g/L of the reaction mixture, which corresponded to the mass fraction of 6.64-23.7% of dry matter. The data obtained as a result of the present study may be useful for designing an industrial process.

8.
Chem Zvesti ; 71(5): 953-960, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28496290

RESUMO

LC-MS/MS method to determine hydrophobic N-alkyloxy substituted amidines: N-(2-ethylhexyloxy)pyridine-2-carboximidamide, N-(2-ethylhexyloxy)pyridine-3-carboximidamide, N-(2-ethylhexyloxy)pyridine-4-carboximidamide, N-decyloxy pyridine-2-carboximidamide, N-decyloxypyridine-3-carboximidamide and N-decyloxypyridine-4-carboximidamide was developed and validated in terms of linearity, precision and accuracy. The developed method was successfully applied to monitor and control the synthesis process. The experimental data points indicated that the straight chain alkyl bromide reacted most rapidly than branched alkyl bromide and the enhancement of the reaction efficiency strongly depended on reaction temperature.

9.
J Radioanal Nucl Chem ; 307: 1155-1164, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26834307

RESUMO

In present paper the equilibrium of cobalt extraction with 1-(2-pyridyl)tridecan-1-one oxime from the chloride/sulphate solutions was studied. The presented results indicated that extraction depends on a number of process variables, including the pH, metal and Cl- concentration in the aqueous feed, and concentration of the oxime in the organic phase. The created cobalt-complexes with the 2-pyridine ketoxime were stable and only concentrated HCl was found to be a suitable stripping agent for coordinated metal. The separation of Co(II) from Zn(II), Ni(II) and Cu(II) was also studied, but the selective recovery of the metals was possible using the multi-stage stripping process.

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