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81.
Osteoarthritis (OA) typically generates pain, reduced mobility and reduced quality of life. Most conventional treatments for osteoarthritis, such as non-steroidal anti-inflammatory drugs (NSAIDs) and simple analgesics, have side effects. PCSO-524™, a non polar lipid extract from the New Zealand Green Lipped Mussel, is rich in omega-3 fatty acids and has been shown to reduce inflammation in both animal studies and patient trials. This OA trial examined pain relief changes in relation to quality of life and safety of use for OA patients who took PCSO-524™ compared with patients who took fish oil (containing an industry standard EPA-18% and DHA-12% blend). PCSO-524™ patients showed a statistically significant improvement compared with patients who took fish oil. There was an 89% decrease in their pain symptoms and 91% reported an improved quality of life. Patients treated with fish oil showed significantly less improvement and a greater level of physical discomfort during the study. These results suggest that PCSO-524™ might offer a potential alternative complementary therapy with no side effects for OA patients.  相似文献   
82.
This study demonstrated that the novel isoelectric solubilization/precipitation can be applied to recover functional muscle protein in a continuous mode from whole Antarctic krill. Protein recovered from whole krill had a much lower ash content than whole krill, suggesting good removal of inedible impurities (shell, appendages, etc.). Lipids were retained to a higher degree with krill protein solubilized at acidic rather than basic pH. The viscoelastic modulus (G') showed that recovered krill protein failed to form heat-induced gel unless beef plasma protein (BPP) was added. Therefore, protease inhibitors are suggested for development of krill-derived products. Even with BPP, the G' decreased between 45 and 55 degrees C. However, krill protein solubilized at acidic pH had a higher decrease of the G' than the protein solubilized at basic pH, likely due to krill endogenous cathepsin L. Krill protein-based gels developed from protein solubilized at basic pH, especially pH 12.0, had better texture (torsion and Kramer tests and texture profile analysis) than acidic counterparts, possibly due to higher proteolysis and denaturation at acidic pH. Gels made from protein solubilized at acidic pH were brighter and whiter likely due to a higher lipid content.  相似文献   
83.
Parasites are thought to increase the risk of host extinction, but their dynamics in endangered species have not been well investigated. The free-living European bison population in Bia?owie?a Forest has recently been massively invaded by a blood-sucking nematode, Ashworthius sidemi. This nematode originated in Asia and was probably transmitted to Europe with the introduction of the sika deer. Here, we investigate the impacts of genetic factors (the Major Histocompatibility Complex class II genes responsible for extracellular parasite recognition) and management practices (supplementary feeding affecting winter population density) on the intensity of A. sidemi infections in bison. All but two out of 110 animals investigated between 2005 and 2009 were infected with A. sidemi, and the intensity of infection increased significantly with time. Due to a severe population bottleneck experienced by the bison, only four class II DRB alleles are retained in the Bia?owie?a population. We found that despite high sequence divergence, neither any of the alleles nor DRB heterozygosity was significantly associated with infection intensity. We did find, however, that winter density of bison herds was positively associated with infection intensity. Winter bison population densities were in turn predicted by the intensity of supplementary feeding.  相似文献   
84.
We have studied spatial field-scale variability of soil dehydrogenase (DH) and cellulase activities (CEL) and their relationship with variability of some physico-chemical properties at the surface horizon of the agricultural field. Soil samples were collected at 50 points from the upper 20 cm of soil. The activity of DH ranged between 0.77 and 1.5 μM TPP·g−1·h−1 while CEL activity ranged from 0.8 to 1.94 μM glucose·g−1·24 h−1. Concentrations of CORG and TN varied from 8.5 to 31.7 g·kg−1 and from 0.94 to 3.56 g·kg−1, respectively. The soil data showed that spatial variability and semivariograms describe spherical and linear models with the nugget effect (DH, CEL, CORG and TN). Dehydrogenase activity was in the strong variability class, while cellulase activity was situated in the week variability class. Both CORG and TN concentrations and pHKCl values were strongly spatially dependent with the percentage of total variance (sill) presents as nugget variance ranging from 8.9% to 16.1%. Kriged maps displayed the lowest values of CEL activities in the north-east of the area, while the south area showed the highest CEL activity. The DH activity values were irregularly distributed in the surface horizon of the studied soil and this behaviour did not correspond with the spatial distribution of other properties.  相似文献   
85.
The standard artificial reproduction technique with the use of Ovopel (GnRH analogue) was evaluated for the critically endangered cyprinid species in Poland, the lake minnow Eupallasella perenurus. Wild spawners were angled at the beginning of the spawning season. Only females with a condition coefficient value higher than the mean were included in the experiment and then stimulated with Ovopel. Group A (n = 20) was given standard treatment (0.2 pellet kg–1 and 1.0 pellet kg–1 after 12 h), whereas group B (n = 8) was treated with a single dose of 2.0 pellets kg–1. After fertilisation with the dry method, the glutinous eggs attached to the bottom of flow-through aquaria were incubated at 17.1–18.4°C. Throughout incubation (85D°), dead eggs were removed and counted. The same was done with dead larvae, those with deformed bodies or those with empty alimentary tracts after 2 days of external feeding. Two injections of Ovopel resulted in a significantly (P 0.05) higher ovulation rate in comparison with the single dose (70 and 25% in groups A and B, respectively). The individual hatching rates were very high (98.4–100%), as was the share of good quality larvae (91.1 and 96.5% of stripped eggs in groups A and B, respectively). These results indicate that the standard propagation method used with commercially important cyprinid species can also be used to successfully breed E. perenurus.  相似文献   
86.
Enterotoxigenic Escherichia coli (ETEC) may produce heat-labile (LT) and heat-stable (STI or STII) enterotoxins. Differentiation between ETEC and other pathogenic and non-pathogenic E. coli as well as other Gram-negative bacteria responsible for induction of diarrhoea, requires isolation, biochemical identification and determination of toxins (or their genes--elt, estI, estII). A multiplex polymerase chain reaction (PCR) system for the rapid and specific detection of enterotoxin-gene-positive E. coli was developed. The primers described by other authors, specific for the universal stress protein A (UspA) of E. coli and enterotoxin genes were used and allowed a simultaneous amplification of the E. coli-specific uspA and the respective toxin genes. The specificity of this multiplex PCR system was confirmed by testing ETEC, non-ETEC and other non-E. coli bacteria. The specific 884 bp uspA gene and 280 bp (eltI), 166 bp (estI) or 278 bp (estII) amplification products were generated with the respective ETEC strains whereas no amplification was detected with non-E. coli bacteria. The multiplex PCR developed allowed the rapid and specific identification of enterotoxin-producing E. coli colonies directly grown from faecal samples of pigs with diarrhoea. The test may be used as a method for the determination of ETEC among other pathogenic groups of E. coli and other Gram-negative enteric isolates.  相似文献   
87.
BackgroundDue to multiple similarities in the structure and physiology of human and pig skin, the pig model is extremely useful for biological drug testing after subcutaneous administration. Knowledge of the differences between subcutaneous injection sites could have a significant impact on the absorption phase and pharmacokinetic profiles of biological drugs.ObjectivesThis study aimed to analyze the impact of administration site on pharmacokinetics and selected biochemical and hematological parameters after a single subcutaneous administration of ustekinumab in pigs. Drug concentrations in blood plasma were analyzed by enzyme-linked immunosorbent assay. Pharmacokinetic analyses were performed based on raw data using Phoenix WinNonlin 8.1 software and ThothPro v 4.1.MethodsThe study included 12 healthy, female, large white piglets. Each group received a single dose of ustekinumab given as a 1 mg/kg subcutaneous injection into the internal part of the inguinal fold or the external part of the inguinal fold.ResultsThe differences in absorption rate between the internal and external parts of the inguinal fold were not significant. However, the time of maximal concentration, clearance, area under the curve calculated between zero and mean residence time and mean residence time between groups were substantially different (p > 0.05). The relative bioavailability after administration of ustekinumab into the external part of the inguinal fold was 40.36% lower than after administration of ustekinumab into the internal part of the inguinal fold.ConclusionsHealthy breeding pigs are a relevant model to study the pharmacokinetic profile of subcutaneously administered ustekinumab.  相似文献   
88.

? Key message

Long-term strict protection of woodland communities may lead to their compositional simplification and homogenisation.

? Context

In the past, it has often been postulated that structures and processes typical for natural forests should be mimicked by silvicultural activities in the case of managed tree stands.

? Aims

To determine which features and traits of natural woodland communities (alongside typical old-growth attributes) should be imitated in managed forests, as well as which should not (and for what reasons).

? Methods

Tree data from five permanent study plots (of a total area of 15.44 ha) established in 1936 in the core area of the Bia?owie?a National Park (NE Poland) are used to calculate several quantitative indices describing the temporal dynamics (in terms of stand structure and composition) of eight major woodland community types.

? Results

Most structural attributes revealed rather high stability over time. In contrast to these, during the observation period, noticeable changes in the composition of particular Bia?owie?a woodland communities have been taking place, related to declining occurrence and reduced roles characteristic for a large number of tree species.

? Conclusion

In many ways, natural forests can serve as an important model for managed forest stands. However, in certain circumstances, silvicultural treatments counteracting natural developmental trends may appear to be indispensable, especially when more diverse and stable tree species composition (at a given spatial and temporal scale) is indicated or desirable.
  相似文献   
89.

? Key message

Natural regeneration of P. abies (L.) H. Karst. may reach high densities in lower mountain elevations. The highest densities were found in sites with moderate light availability, with low pH, and not near the riverbank. However, age-height classes differed in the predicted magnitude of response, but were consistent in response directions. Mosses and understory species typical of coniferous forests were positively correlated with regeneration density.

? Context

Norway spruce Picea abies (L.) H. Karst. in Central Europe is at risk under climate change scenarios, particularly in mountain regions. Little is known about the impact of environmental factors on the natural regeneration of P. abies in low-elevation mountain forests.

? Aims

We aimed to assess impacts of distance from the riverbank, soil pH, and light availability on natural P. abies regeneration. We hypothesized that (1) natural P. abies regeneration would depend on light availability and soil pH and (2) there are understory plant species which may indicate the microsites suitable for natural regeneration of P. abies.

? Methods

The study was conducted in the Sto?owe Mountains National Park (SW Poland, 600–800 m a.s.l.). We established 160 study plots (25 m2) for natural regeneration, light availability, soil pH, and understory vegetation assessment.

? Results

The highest densities of natural regeneration of P. abies were observed in sites with moderate light availability (0.1–0.2 of open sky) and low pH (3.5–4.5), and located relatively far from the riverbank. Cover of 22 understory plant species were correlated with natural P. abies regeneration densities, mostly positively.

? Conclusion

Different stages of natural regeneration of P. abies revealed different regeneration niches. Most understory plant species (bryophytes and herbs typical of coniferous forests) do not compete with natural regeneration of P. abies.
  相似文献   
90.
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