RESUMO
Electron paramagnetic resonance (EPR) oximetry based on lithium naphthalocyanine paramagnetic crystals as oxygen sensors enables direct measurement of the partial pressure of oxygen (pO2) in tissues. The method uses topical or implantable forms of these oxygen-sensing crystals embedded in a biocompatible siloxane elastomer. This article presents a summary of these sensors for EPR oximetry and their applicability for tissue oxygen measurement in the clinic.
Assuntos
Oximetria , Oxigênio , Espectroscopia de Ressonância de Spin Eletrônica , Pressão Parcial , Próteses e ImplantesRESUMO
The study on polymorphism within the STAT5A gene (transition C6853T) was conducted using the PCR-RFLP method and AvaI restrictase. The study covered a herd of 723 cows of the Polish Red-and-White variety of Holstein Friesian breed, kept for dairy purposes in the Opole region, Poland. Two alleles (C and 7) of the analyzed STAT5A polymorphism were found in the studied herd. The alleles determined the occurrence of two genotypes: CC and CT. The homozygous TT genotype was not found. The STAT5A/AvaI allele frequencies were as follows: C--88.31% and T--11.69%, whereas the genotype frequencies were 76.6% for CC and 23.4% for CT. The analysis of associations between the STAT5A/AvaI polymorphism and milk utility traits considered in the study showed that these traits were different in animals with different STAT5A/AvaI genotypes.
Assuntos
Leite/metabolismo , Polimorfismo Genético , Fator de Transcrição STAT5/genética , Alelos , Animais , Bovinos , Desoxirribonucleases de Sítio Específico do Tipo II/química , Feminino , Lactação , Polônia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de RestriçãoRESUMO
Nanocrystalline chitosan (NCC) is a modified form of chitosan, prepared from the method for obtaining chitosan acetate (CA). Due to the greater crystallinity of chitosan nanoparticles in relation to CA, NCC is more thermally stable and thus has great potential in the development of a new generation of biomaterials potentially useful in regenerative medicine and tissue engineering. NCC is also characterized by having similar properties to its precursor chitosan, such as its biocompatibility, bioactivity, ability to be bioabsorbed and lack of toxicity. One of the major problems associated with obtaining NCC is the low productivity of the methods. While known methods of obtaining nanostructures produce small amounts (milligrams), the method of synthesis for creating NCC from its salt is often more productive and less costly, and is patented by the authors of this work (registration number: BR10201702272). Thus, the objective of this study was to characterize NCC obtained through this innovative method, and analyze its chemical and physical properties using Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and mechanical property analysis with the mean values for the elasticity module, the resistance to tensile strength and the tensile strength. The results indicate that this new process of obtaining the NCC did not modify the chemical structure of the chitosan. The structure of the film surface created was homogeneous and the mechanical properties emphasized the plastifying effect of glycerol under NCC. The thermogravimetric analysis of NCC indicated greater stability in the polysaccharide structure of the nanocrystalline, due to an increased crystalline region compared to the CA which was confirmed by DSC.
Assuntos
Quitosana/química , Nanopartículas/química , Configuração de Carboidratos , Cristalização , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Resistência à TraçãoRESUMO
A total of 129 Limousin calves were used to investigate how leptin gene polymorphisms affect growth traits, such as body weight, average daily gain, wither height, sacrum height and chest girth in beef cattle. Two single nucleotide polymorphisms (SNPs) were genotyped, including the Sau3AI polymorphism in intron 2 and the A59V polymorphism in exon 3. The genotype and allele frequencies for each SNP and the haplotype frequencies for both SNPs were estimated in the studied herd. Statistical analysis revealed that the A59V polymorphism significantly affected the body weight at 210 days of age (P < or = 0.01) and the average daily gain between 3 and 210 days of age (P < or = 0.05) with Tas a desirable allele. No associations were observed between the Sau3AI polymorphism and the growth traits mentioned above. However, the average daily gain between 3 and 210 days of age was significantly higher in the CT/CT haplotype animals compared with the CC/CC and CC/CT individuals. These results indicated that selection for the A59V TT animals might contribute to an improved body weight in Limousin cattle.
Assuntos
Bovinos/crescimento & desenvolvimento , Bovinos/genética , Leptina/genética , Polimorfismo de Nucleotídeo Único , Animais , Peso Corporal/genética , Peso Corporal/fisiologiaRESUMO
Molsidomine, coronary drug which acts similar to organic nitrates, belongs to the drug class of sydnones . SIN-1A metabolite of Molsidomine has pharmacologically active group of NO, which by increasing levels of cGMP, decreases levels of intracellular calcium ions in smooth muscle cells. This effect leads to relaxation of smooth muscle vasculature, inhibits platelets aggregation and has indirect antiproliferative effect. In clinical observations no effect of tolerance to the drug was observed. Experimental data show additional mechanism of action of the drug: SIN-1C metabolites protects the reoxygenated cardiomyocyte from post-reperfusion damage. Indications for use of Molsidomine are: ischaemic heart disease, chronic heart failure and pulmonary hypertension. Effects of Molsidomine use in acute myocardial infarction and unstable angina were compared in clinical trials to effects of nitroglycerin use. Both drugs were found equally potent, but authors underline the fact of better Molsidomine tolerability comparing NTG, but longer serum half-time of Molsidomin effects that control of the treatment is worse. In clinical trials it was suggested that intravenous use of Molsidomine metabolite SIN-1 during PTCA procedures is more effective than use of isosorbide dinitrate in the same procedures. In other clinical trials molsidomin was found to produce beneficial effects in patients with heart failure due to ischaemic cardiomyopathy, dilatative cardiomyopathy, in essential hypertension, pulmonary artery hypertension in COPD patients and in congestive heart failure.
Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Molsidomina/uso terapêutico , Vasodilatadores/uso terapêutico , Cálcio/metabolismo , Ensaios Clínicos como Assunto , GMP Cíclico/metabolismo , Meia-Vida , Humanos , Molsidomina/farmacologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Vasodilatadores/farmacologiaRESUMO
The aim of the study was to investigate associations between combined defensin genotypes (CDGs) and somatic cell count (SCC) in Jersey cows. The study included a herd of 184 dairy Jersey cows from Wielkopolska region in Poland. Polymerase chain reaction-restriction fragment length polymorphism analysis with TaqI restrictase established the existence of 12 CDGs with a frequency of over 1%. The most frequent were A1A2B1B2C1C2 and A1A2B1B2C1- genotypes with a frequency of 56.9783% and 12.5% respectively. The study also confirmed the existence of a statistically significant association between SCC and the year of study, season, lactation stage and cow. The highest SCC (transformed into a logarithmic scale) was found in the milk of cows with A1-B1-C1C2 genotype, whereas the lowest one in cows with A2-B1B2C1C2 genotype. Another aim of the project was to study the association between CDG and milk production traits, such as daily milk yield and fat and protein content. CDG was found to be a significant factor affecting daily milk yield and non-significant for fat and protein content. The highest daily milk yield was observed in cows with CDGs A1A2B1B2C2- and -A2-B1B2C1-, whereas the lowest one was characteristic of -A2-B1-C1C2 and A1A2B1-C1- animals. Fat content was found to be related to CDG genotype in the opposite way; the highest values were recorded in animals with -A2-B1B2C1- genotype, the lowest - in animals with -A2-B1-C1C2 genotype. Similar results were observed in protein content in milk -A2-B1B2C1-, the highest content and -A2-B1-C1C2, the lowest content. The results confirm the hypothesis of using CDG as an SCC marker. However, further studies should be conducted to confirm these results before CDG can be used as a marker in a mass selection of dairy cows.