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OBJECTIVE: To compare measurements of myeloperoxidase (MPO) in plasma, laminar tissues, and skin obtained from control horses and horses given black walnut heartwood extract (BWHE). ANIMALS: 22 healthy 5- to 15-year-old horses. PROCEDURES: Horses were randomly assigned to 4 groups as follows: a control group given water (n = 5) and 3 experimental groups given BWHE (17) via nasogastric intubation. Experimental groups consisted of 5, 6, and 6 horses that received BWHE and were euthanatized at 1.5, 3, and 12 hours after intubation, respectively. Control horses were euthanatized at 12 hours after intubation. Plasma samples were obtained hourly for all horses. Laminar tissue and skin from the middle region of the neck were harvested at the time of euthanasia. Plasma and tissue MPO concentrations were determined via an ELISA; tissue MPO activity was measured by use of specific immunologic extraction followed by enzymatic detection. RESULTS: Tissues and plasma of horses receiving BWHE contained significantly higher concentrations of MPO beginning at hour 3. Laminar tissue and skin from horses in experimental groups contained significantly higher MPO activity than tissues from control horses. Concentrations and activities of MPO in skin and laminar tissues were similar over time. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, BWHE administration causes increases in MPO concentration and activity in laminar tissue and skin and the time of increased MPO concentration correlates with emigration of WBCs from the vasculature. These findings support the hypothesis that activation of peripheral WBCs is an early step in the pathogenesis of acute laminitis.  相似文献   
3.
The chromosomal localization of the genes encoding the four subunits of muscle nicotinic receptor was determined by analyzing restriction fragment length polymorphisms between two mouse species Mus musculus domesticus (DBA/2) and Mus spretus (SPE). Analysis of the progeny of the interspecies mouse backcross (DBA/2 X SPE) X DBA/2 showed that the alpha-subunit gene cosegregates with the alpha-cardiac actin gene on chromosome 17, that the beta-subunit gene is located on chromosome 11, and that the gamma- and delta-subunit genes cosegregate and are located on chromosome 1.  相似文献   
4.

Purpose

Soils provide a variety of ecosystem services (ESs) that are crucial to food security, water security, energy security, climate change abatement, and biodiversity, especially in densely populated countries such as China. At present, China is facing great challenges from serious soil heavy metal (HM) contamination which has damaged soil ESs and soil security. In this paper, we evaluate the ESs that contaminated soils can potentially provide before and after remediation, and we explore the connections between these ESs and the achievement of soil security in China.

Materials and methods

After an introduction to the concepts of ESs and soil security and a review of the current status of soil HM contamination in China, the ESs that can potentially be provided by HM-contaminated soils are discussed. Finally, we discuss the current remediation status of HM-contaminated soils from the standpoint of optimizing the ability of these soils to provide ESs.

Results and discussion

The status of the provision of ESs by HM-contaminated soils of croplands, brownfields, and mining wastelands is described in detail. Contaminated cropland soils fail to provide provisioning (e.g., food production), cultural, and regulating services, while the regulating and supporting services of brownfield soils are greatly reduced. The ESs of mining wasteland soils have been severely damaged, resulting in a high potential for contamination of surrounding ecosystems. Recent soil remediation projects have demonstrated that the damaged ESs of HM-contaminated soils can be restored, which would enhance Chinese soil security. However, it has often been the case that only visible ESs (e.g., food production and vegetation cover) are addressed, while other less noticeable but important services (e.g., water quality and biodiversity) are neglected. Therefore, we propose a framework for the evaluation of ESs provided by HM-contaminated soils.

Conclusions

The ESs that could potentially be provided by HM-contaminated soils would help to achieve soil security in China, not only by improving food security, water security, and energy security but also by helping to protect soil biodiversity and abate global climate change. The ESs provided by HM-contaminated soils should be taken into account in soil policy and management systems as well as by the remediation industry.
  相似文献   
5.
Objectives – The aim of this study is to describe the prevalence of postoperative laminitis in colic cases and to determine if low-molecular-weight heparin (LMWH) is effective in preventing this complication.
Design – Retrospective clinical study.
Animals – Client-owned horses.
Interventions – SC administration of enoxaparin during the postoperative period.
Measurements and Main Results – Medical records of 360 horses undergoing surgery for colic and surviving at least 3 days were evaluated. Fifty-six horses admitted before 1995 did not receive LMWH (control group) and 304 admitted after 1995 received LMWH as a prophylaxis for laminitis (treatment group). Three grades of severity were defined for laminitis. Prevalence and severity of laminitis were compared between the 2 groups. Several parameters recorded on admission (sex, age, breed, site and nature of the disease, heart rate, PCV, gravity score, and shock score) and the administration of LMWH were tested as risk factors in the development of laminitis in a logistic regression procedure. Prevalence and grade of laminitis were significantly lower in the treatment group. Only the absence of LMWH was recognized as a significant risk factor in the logistic regression model.
Conclusions – The administration of LMWH appears to be effective in the prophylaxis of laminitis following colic surgery and may be useful in the postoperative management of these horses.  相似文献   
6.
The industrial wastewater from resin production plants contains as major components phenol and formaldehyde, which are traditionally treated by biological methods. As a possible alternative method, electrochemical treatment was tested using solutions containing a mixture of phenol and formaldehyde simulating an industrial effluent. The anode used was a dimensionally stable anode (DSA?) of nominal composition Ti/Ru0.3Ti0.7O2, and the solution composition during the degradation process was analyzed by liquid chromatography and the removal of total organic carbon. From cyclic voltammetry, it is observed that for formaldehyde, a small offset of the beginning of the oxygen evolution reaction occurs, but for phenol, the reaction is inhibited and the current density decreases. From the electrochemical degradations, it was determined that 40?mA?cm?2 is the most efficient current density and the comparison of different supporting electrolytes (Na2SO4, NaNO3, and NaCl) indicated a higher removal of total organic carbon in NaCl medium.  相似文献   
7.
UV radiation is able to induce lipid peroxidation. Photooxidation-induced beta-sitosterol oxides were monitored in four vegetable oils exposed to sunlight for 10, 20, and 30 days during May 2005 (northeastern France), exposed to artificial light generated by a high-pressure Hg lamp for 21, 42, and 63 h at room temperature, and exposed to a 10 MeV electron beam at 0.93, 2.69, and 9.30 kGy at 8 degrees C. Quantification was performed by capillary gas chromatography-mass spectrometry according to the total ion current mode and using a reconstructed ion trace chromatogram with specific ion fragments. Sunlight induced the formation of higher amounts of oxides than UV light, while no significant oxidizing effect was observed with electron beam irradiation. However, data suggested that the amount of the main oxides formed was strongly dependent on the dose rate (length of exposure). Accordingly, shorter but more intense treatments had lower oxidizing effects.  相似文献   
8.
Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutrophils during degranulation or after lysis. Post-thaw semen contains MPO, and concentration of this enzyme is associated with decreased motility. The aim of this study was to determine kinetics of MPO concentration during freezing, its origin, and its impact on frozen-thawed semen. Forty ejaculates were used. Semen was frozen using the classical freezing procedure. MPO concentrations were assayed in fresh semen, after centrifugation, and after cooling down to 4°C. Post-thaw MPO assay results and spermogram characteristics were determined. MPO immunocytochemistry was performed on 4 different ejaculates at each step of freezing procedure. MPO concentration increased after cooling down to 4°C and thawing compared with fresh semen. As temperature decreased, MPO was higher or tended to be higher in post-thaw poor quality samples. Nonsperm cells showed various degrees of MPO immunostaining and were observed as epithelial cells with nuclear pyknosis and keratinization. MPO immunostaining increased in medium and decreased in nonsperm cells during freezing. Our study shows that MPO concentration in equine semen increases when temperature decreases. We hypothesize that nonsperm cells present in fresh semen could release MPO.  相似文献   
9.

Purpose  

Constructed soils are Technosols resulting from the deliberate combination of various artefacts. Similarly to natural soils, technogenic parent materials are transformed by pedogenic factors contributing to their evolution. This work was conducted to study the first stages of the pedogenesis of constructed soils.  相似文献   
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