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According to clinical studies, degenerative diseases of canine joints lead to higher lactate dehydrogenase (LDH) levels in synovial fluid. The goal of the present study was to examine the intraarticular distribution of LDH in healthy and osteoarthrotic knee joints in order to identify possible sources of LDH in synovial fluid. As synovial LDH concentrations neither correlate with the number of leukocytes nor with synovitis, our investigation focused on the articular cartilage. Samples from healthy and osteoarthrotic knee joints were fixed and processed for transmission electron microscopy (TEM), immunohistochemistry (IHC), and immunocytochemistry (ICC). In addition, fresh cartilage samples were investigated cytochemically by the tetrazolium‐formazan reaction. Analyses of blood and synovial fluid samples were used to confirm the absence of inflammatory disease. Morphology of articular cartilage was assessed macroscopically and by means of TEM. IHC revealed highest levels of LDH in chondrones and a diffuse labelling of the matrix with a distinctive decrease in signal from superficial to deeper cartilage layers. Ultrastructural localization by ICC showed LDH to be present in the cytoplasm of all chondrocytes and confirmed the density gradient in the matrix. Labelling was absent from nuclei and from pericellular rims. Cytochemistry confirmed the distribution pattern and, thus, expanded our findings beyond immunological evidence by providing proof of enzymatic activity of LDH in articular cartilage. The present results indicate that LDH is transferred from chondrocytes to the cartilaginous matrix. We suggest, therefore, that LDH found in synovial fluid originates from the articular cartilage and that osteoarthrotic processes promote LDH release from the cartilaginous matrix. 相似文献
3.
Hampel V Schwarz B Kempf C Köstlin R Schillinger U Küchenhoff H Fenske N Brill T Hirschberger J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(6):1340-1346
BACKGROUND: Recombinant feline interferon-omega (rFeIFN-omega) was tested as a treatment option for cats with fibrosarcoma to assess safety and feasibility. HYPOTHESIS: Treatment with rFeIFN-omega in cats with fibrosarcoma is safe and feasible. ANIMALS: Twenty domestic cats. METHODS: In an open-labeled uncontrolled clinical trial 12 injections of 1 x 10(6) U/kg rFeIFN-omega were administered over a 5-week period: the 1st through 4th injections were given intratumorally, and the 5th through 12th injections were administered subcutaneously at the tumor excision site. Wide surgical excision of the tumors was carried out after the 4th injection and before the 5th injection of rFeIFN-omega. A Common Terminology Criteria for Adverse Events (CTCAE) analysis was conducted. Flow cytometry of fibrosarcoma cells after incubation with rFeIFN-omega and recombinant feline interferon-gamma was performed to assess the biological effect of rFeIFN-omega. RESULTS: Changes in blood cell count, increases in serum aspartate-amino-transferase activity, serum bilirubin concentration, serum creatinine and serum electrolyte concentrations, weight loss, anorexia, increased body temperature, and reduced general condition were observed but were mostly minor (grade 1 and 2) and self limiting. Eosinophilia (P = .025), neutropenia (P = .021), and weight loss (P < .001) were statistically correlated with rFeIFN-omega-treatment (analysis of parameters before treatment and after 3 injections of rFeIFN-omega). Flow cytometry of 5 unrelated feline fibrosarcoma cell lines showed increased expression of major histocompatibility complex (MHC) class I molecules (P = .026) in response to in vitro incubation with rFeIFN-omega, whereas expression of MHC class II molecules was not affected significantly. CONCLUSIONS AND CLINICAL IMPORTANCE: RFeIFN-omega for the treatment of feline fibrosarcoma is safe, well tolerated, and can be easily performed in practice. To assess the efficacy of the treatment, it should be tested in a placebo-controlled trial. 相似文献
4.
The adaptive response of the omnivorous ide,Leuciscus idus melanotus, to drastic metabolic conditions was analyzed on different levels of organisation investigating a variety of parameters: Organism (condition factor, liver-somatic index), organ (liver structure), cellular and subcellular level (hepatocyte structure, glycogen and lipid storage, contents and distribution of nucleic acids, enzyme alterations).During starvation, ide were able to maintain liver integrity in a biphasic process: after an initial phase of disturbance, ide established a new structural and metabolic homeostasis. Recovery from starvation was possible only with a complete diet but not with a sucrose diet. Carbohydrate overload, as evoked by sucrose refeeding, did not result in liver or carcass fattening as known from mammals.To the best of our knowledge, the present study is the first to use enzyme histochemistry in fish nutrition research. In mammals, histochemistry is particularly helpful for understanding processes of hepatic metabolic adaptation. In fish, however, on the basis of our results, enzyme histochemical studies appear to be of limited value, as long as no further data are available on a zonal distribution of enzyme activities in teleost liver parenchyma. Instead, the histochemical detection of the distribution of hepatic storage products and RNA-positive material yielded important information on liver adaptive processes.Abbreviations H
starvation
- SU
sucrose
- AD
artificial diet
- AcP
acid phosphatase
- G6Pase
glucose-6-phosphatase
- G6PDH
glucose-6-phosphate dehydrogenase
- GLU
-glucuronidase
- ME
malic enzyme
- PHO
glycogen phosphorylase
- UE
unspecific esterase
- RER
rough endoplasmic reticulum 相似文献
5.
Combining agent-based and stock-flow modelling approaches in a participative analysis of the integrated land system in Reichraming, Austria 总被引:1,自引:0,他引:1
Veronika Gaube Christina Kaiser Martin Wildenberg Heidi Adensam Peter Fleissner Johannes Kobler Juliana Lutz Andreas Schaumberger Jakob Schaumberger Barbara Smetschka Angelika Wolf Andreas Richter Helmut Haberl 《Landscape Ecology》2009,24(9):1149-1165
The integrated modelling of coupled socio-ecological systems in land-change science requires innovative model concepts capable of grasping the interrelations between socioeconomic and natural components. Here, we discuss the integrated socio-ecological model SERD (Simulation of Ecological Compatibility of Regional Development) that was developed for the municipality of Reichraming in Upper Austria in a participative 2-year process involving local stakeholders. SERD includes three main components: (1) an agent-based actors module that simulates decisions of farmsteads, the municipal administration and other important actors; (2) a spatially explicit (GIS based) land-use module that simulates land-use change at the level of individual parcels of land and (3) an integrated socio-ecological stock-flow module that simulates carbon and nitrogen flows through both socioeconomic and ecological system compartments. We report on outcomes of a scenario analysis that outlines possible future trajectories depending on both external (e.g. agricultural subsidies and prices) and internal (e.g. innovation, willingness to co-operate) factors. We find that both external and internal factors can affect the behaviour of the integrated system considerably. Local and regional policies are found to be able to counteract adverse global socioeconomic conditions to some extent, but not to reverse the trend altogether. We also find strong interdependencies between socioeconomic and ecological components of the system. Fully evaluating these interdependencies is, however, not possible at the local scale alone and will require explicit consideration of higher-level effects in future research. 相似文献
6.
Bellion P Hofmann T Pool-Zobel BL Will F Dietrich H Knaup B Richling E Baum M Eisenbrand G Janzowski C 《Journal of agricultural and food chemistry》2008,56(15):6310-6317
Apples represent a major dietary source of antioxidative polyphenols. Their metabolic conversion by the gut microflora might generate products that protect the intestine against oxidative damage. We studied the antioxidant effectiveness of supernatants of fermented apple juice extracts (F-AEs, 6 and 24 h fermentation) and of selected phenolic degradation products, identified by HPLC-DAD-ESI-MS. Cell free antioxidant capacity of unfermented apple juice extracts (AEs) was decreased after fermentation by 30-50%. In the human colon carcinoma cell line Caco-2, F-AEs (containing <0.5% of original AE-phenolics) decreased the reactive oxygen species (ROS) level more efficiently than the F-blank (fermented without AE) but were less effective than the respective AEs. Similarly, antioxidant effectiveness of individual degradation products was lower compared to respective AE constituents. Glutathione level was slightly increased and oxidative DNA damage slightly decreased by fermented AE03, rich in quercetin glycosides. In conclusion, F-AEs/degradation products exhibit antioxidant activity in colon cells but to a lesser extent than the respective unfermented AEs/constituents. 相似文献
7.
8.
Bodi D Fry H Schafft H Lahrssen-Wiederholt M Preiss-Weigert A 《Journal of agricultural and food chemistry》2012,60(28):6946-6952
Maduramicin is a coccidiostat authorized as feed additive in the European Union for chickens and turkeys for fattening but not for laying hens, considering the risk of residues in eggs. The unavoidable cross-contamination of non-target feed with coccidiostats is regulated by Commission Directive 2009/8/EC and resulting carry-over in food by Commission Regulation (EC) No. 124/2009. To verify the compliance of the maximum levels for maduramicin in feed (50 μg/kg) and eggs (2 μg/kg), the carry-over from feed into eggs was investigated. Diets containing 10, 30, and 50 μg of maduramicin/kg of feed were fed to laying hens. Feed, egg white, and yolk were analyzed by LC-MS/MS. Maduramicin residues were only detected in in egg yolk. Feeding the 10 μg/kg maduramicin diet resulted in maduramicin concentrations up to 2.5 μg/kg in whole eggs, already exceeding the maximum level. A carry-over rate of 8% maduramicin from feed into eggs was calculated. 相似文献
9.
银杏内生真菌菌株R2的鉴定及其抑菌活性 总被引:2,自引:0,他引:2
以金黄色葡萄球菌(Staphylococcus aureus)、大肠杆菌(Escherichia coli)和枯草芽孢杆菌(Bacillus subtilis)3种微生物为指示菌,采用杯碟法对分离自药用植物银杏(Ginkgo biloba L.)的36株内生真菌进行抗菌活性检测。并通过形态学特征观察和ITS-rDNA序列系统发育分析对强抑菌活性菌株进行鉴定。结果发现,菌株L1、L4、L5、L7、T2、T3、R1和R2等8株内生真菌的发酵粗提物具有抑菌活性,其中以内生真菌R2的抑菌活性最高,抑菌圈直径分别为20 mm、20 mm和21 mm。结合形态学特征和ITS-rDNA序列分析确定菌株R2为尖孢枝孢菌(Cladosporium oxysporum)。 相似文献
10.
XIAO Wen-juan LI Nan GONG Ying-xue WANG Jun-mei QUAN Yan-cai LIU Ze-huan△ 《园艺学报》2010,26(6):1193-1197
AIM: Toll-like receptor 4 (TLR4) was an important pathogen recognition receptor in the innate immune system. The aim of this study was to investigate the distribution of TLR4 polymorphisms in the general population of China. METHODS: Peripheral blood samples were collected from 191 unrelated healthy Chinese Cantonese individuals. The functional regions of TLR4 locus, including promoter region and all three exons with their surrounding intronic regions were amplified using polymerase chain reaction. After purified, the amplified products were directly sequenced on both strands. RESULTS: A total of eight single nucleotides polymorphisms (SNPs) were detected, five of which were novel. The most common SNP were -1607 C/T with the minor allele frequency of 0.283. Two nonsynonymous substitutions Asp299Gly and Thr399Ile, which were common in Caucasus, were not detected in Cantonese. Neutrality test revealed that TLR4 in Chinese Cantonese was not significantly deviated from the neutral model. CONCLUSION: This is the new finding on the distribution of TLR4 SNPs in the general population of China. It provides several ethnic specific SNPs for further disease association studies of TLR4 polymorphisms in Chinese populations. 相似文献