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51.
The effects of biochar addition in improving soil physical properties are not clearly understood in mining tailings. The objective of this study was to determine the effects of three different types of biochars, in addition to marble mud (MM) and their mixtures, on the structural stability and water retention of mine wastes in Cartagena, Spain. Biochars were produced at 500 °C from pig manure (PM), cotton (Gossipium hirsutum L.) crop residues (CR) and municipal solid waste (MSW). Biochars were added to the mine waste (MW) along with MM and a control (no amendments added). These mixtures were incubated in cores for 90 days (25 °C). PM and CR mixed with MM decreased soil bulk density (from 0 · 98 g cm‐3 to 0 · 89 and 0 · 84 g cm−3, respectively). Amendments had no significant effect on total porosity whereas they increased gas diffusion by 100%, except for MSW. MM improved the plant available water from 0 · 59 to 2 · 56 cm as its combination with biochars, extremely relevant in water scarce climates. The micropores were likely replaced by mesopores when application of PM, CR, MM, and biochars + MM and they improved water retention. Total carbon (TC) and total nitrogen (TN) increased by using biochars and MM and no significant effects were assessed on aggregates. In general, MM mixed with PM and CR derived biochar improved the structural stability and exhibited a strong impact in reclaiming physical quality on mine tailings. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
52.
The aim of the current study was to measure circulating metabolic and inflammation-related biochemical analytes in obese cats before and after weight loss. Thirty-seven overweight neutered cats were studied, median body weight 6.85 kg (range, 4.70 to 10.30 kg), representing a range of ages and both sexes. An individualized weight-loss program was devised for each cat and monitored until completion. Body fat mass was determined by dual-energy x-ray absorptiometry, whereas plasma concentrations of acute-phase proteins (APPs; eg, haptoglobin and serum amyloid A), hormones (eg, insulin, IGF-1, and adiponectin), and enzymes (eg, butyrylcholinesterase and paraoxonase type 1 [PON-1]) associated with inflammation and metabolic compounds (eg, glucose) were also measured. No significant changes were found in APPs after weight loss (P > 0.3), but significant increases in plasma adiponectin (P = 0.021) and IGF-1 (P = 0.036) were seen, whereas insulin (P < 0.001) and homeostasis model assessment (P = 0.005) decreased significantly. Plasma concentrations before weight loss of PON-1 (P = 0.004), adiponectin (P = 0.02), and IGF-1 (P = 0.048) were less in cats that failed to complete weight loss than cats that were successful, whereas glucose concentration was greater. Finally, multivariable linear regression analysis showed that lean tissue loss during weight management was associated with percentage weight loss (greater weight loss, greater lean tissue loss; R = 0.71, P < 0.001) and plasma adiponectin concentration before weight loss (lesser adiponectin, more lean tissue loss; R = -0.52, P = 0.023). In conclusion, various metabolic abnormalities occur in feline obesity, and these can be linked to outcomes of weight-loss programs. The changes that occur with weight loss suggest an improved metabolic status.  相似文献   
53.
The research of new tyrosinase inhibitors is currently important for the development of skin whitening agents; particularly, birch leaves extracts are included in many skin cosmetic products. In this study, the potential ability of Betula pendula leaves ethanolic extract (BE) was evaluated on mushroom tyrosinase activity. Results showed that BE was capable to inhibit dose-dependently l-DOPA oxidation catalyzed by tyrosinase. The inhibition kinetics, analyzed by Lineweaver-Burk plots, showed a noncompetitive inhibition of BE towards the enzyme, using l-DOPA as substrate. The inhibitory mechanism of BE as studied by spectrophotometric analysis, demonstrated its ability to chelate copper ion in the active site of tyrosinase. In addition, BE exhibited Fe(2+)-chelating ability (IC(50)=614.12±2.14 μg/mL), reducing power and radical-scavenging properties (IC(50)=137.22±1.98 μg/mL). These results suggest the usefulness of birch leaves extracts in cosmetic and pharmaceutical industries for their skin-whitening and antioxidant effects. Determination of the polyphenolic compounds in BE extracts was afterward achieved by means of high-performance liquid chromatography (HPLC) with photodiode array (PDA) and mass spectrometry (MS) detection. A total of 25 compounds were positively identified, through the complementary analytical information, and are reported in such a matrix for the first time. Knowledge on the qualitative composition and contents of these natural sources in fact represents mandatory information, for rational consumption and correlation of the beneficial effects to the specific amounts.  相似文献   
54.
Regain after weight loss is widely reported in humans, but there is little information on this phenomenon in dogs. The current study aim was to determine long-term success of a weight loss regime and those factors linked with regain. Thirty-three obese dogs, that had successfully lost weight, were included, all enrolled between December 2004 and May 2009. After weight loss, dogs were switched to a maintenance regime and follow-up weight checks were performed periodically. A review of cases that had completed their weight programme was held during the summer of 2010 and a follow-up check was subsequently conducted, where dogs were reweighed and information was collected on current feeding practices. Median duration of follow-up was 640 days (119-1828 days). Fourteen dogs (42%) maintained weight, 3 (9%) lost >5% additional weight, and 16 (48%) gained >5% weight. Dogs fed a purpose-formulated weight loss diet regained less weight than those switched onto a standard maintenance diet (P=0.0016). Energy intake at the time of follow-up was significantly higher in those dogs fed a standard maintenance diet, compared with those that had remained on a purpose-formulated weight loss diet (P=0.017). These results suggest that weight regain occurs in about half of dogs after successful weight loss. Long-term use of a purpose-formulated weight management diet can significantly limit regain in the follow-up period, likely by limiting food intake.  相似文献   
55.
The objective of this study was to evaluate three commercially-available human assays for the determination of adiponectin, ghrelin and insulin-like growth factor 1 (IGF-1) concentrations in feline serum samples. Intra- and interassay coefficients of variation were lower than 20%, 15% and 6% for adiponectin, ghrelin and IGF-1 assays, respectively. Dilutions of feline serum pools resulted in linear regression equations in all kits. Mean recovery of adiponectin, ghrelin and IGF-1 assays were 107%, 102% and 105%, respectively. Significant differences were detected in adiponectin and ghrelin concentrations between lean and obese cats (P <0.05 in both cases), but there was no difference in IGF-1 concentrations (P = 0.12).  相似文献   
56.
Obesity is thought to affect quality of life, but limited objective data exist to support this supposition. The current study aim was to use a questionnaire to determine health-related quality of life (HRQOL) both before and after weight loss, in obese client-owned dogs. Fifty obese dogs were included, and represented a variety of breeds and genders. Prior to weight loss, owners were asked to complete a validated standardised questionnaire to determine HRQOL. Thirty of the dogs successfully completed their weight loss programme and reached target, and owners then completed a follow-up questionnaire. The completed questionnaire responses were transformed to scores corresponding to each of four factors (vitality, emotional disturbance, anxiety and pain), and scored on a scale of 0-6. Changes in the scores were used to explore the sensitivity of the questionnaire, and scores were correlated with responses to direct questions about quality of life and pain, as well as weight loss. Dogs that failed to complete their weight loss programme had lower vitality and higher emotional disturbance scores than those successfully losing weight (P=0.03 for both). In the 30 dogs that completed, weight loss led to an increased vitality score (P<0.001), and decreased scores for both emotional disturbance (P<0.001) and pain (P<0.001). However, there was no change in anxiety (P=0.09). The change in vitality score was positively associated with percentage weight loss (r(P)=0.43, P=0.02) and percentage body fat loss (r(P)=0.39, P=0.03). These results indicate demonstrable improvement in HRQOL for obese dogs that successfully lose weight.  相似文献   
57.
Obesity is now a major disease of dogs, predisposing to numerous disorders including diabetes mellitus. Adipocytes are active endocrine cells, and human obesity is characterized by derangements in inflammatory adipokine production. However, it is unclear as to whether similar changes occur in dogs. The purpose of the current study was to assess insulin sensitivity and inflammatory adipokine profiles in dogs with naturally occurring obesity and to investigate the effect of subsequent weight loss. Twenty-six overweight dogs were studied, representing a range of breeds and both sexes. All dogs underwent a weight loss program involving diet and exercise. Body fat mass was measured by dual-energy x-ray absorptiometry; plasma concentrations of insulin, glucose, and a panel of inflammatory adipokines (including acute-phase proteins, cytokines, and chemokines) were also analyzed. Body fat mass before weight loss was positively correlated with both plasma insulin concentrations (Kendall τ = 0.30, P = 0.044) and insulin:glucose ratio (Kendall τ = 0.36, P = 0.022), and both decreased after weight loss (P = 0.0037 and 0.0063, respectively). Weight loss also led to notable decreases in plasma tumor necrosis factor-α (TNF-α), haptoglobin, and C-reactive protein concentrations (P < 0.05 for all), suggesting improvement of a subclinical inflammatory state associated with obesity. This study has demonstrated that in obese dogs, insulin resistance correlates with degree of adiposity, and weight loss improves insulin sensitivity. Concurrent decreases in TNF-α and adipose tissue mass suggest that in dogs, as in humans, this adipokine may be implicated in the insulin resistance of obesity.  相似文献   
58.
An unusual vascular ring anomaly consisting of a persistent right aortic arch and a left ligamentum arteriosum extending from the main pulmonary artery to an aberrant left subclavian artery and left aortic arch remnant complex was identified in a German shepherd dog and a great Dane. The left subclavian artery and left aortic arch remnant complex originated at the junction between the right distal aortic arch and the descending aorta and coursed dorsal to the oesophagus in a cranial direction. The attachment of the ligamentum arteriosum to the aberrant left subclavian artery was approximately 5 cm cranial to the point of origin of the aberrant left subclavian artery and left aortic arch remnant complex from the descending aorta in both dogs. This anomaly observed in both dogs is similar to an anomaly reported in humans, in which a persistent right aortic arch is found in conjunction with an aberrant left subclavian artery and a left aortic arch remnant (Kommerell's diverticulum). Surgical ligation and division of the left ligamentum arteriosum in both dogs, along with division of the left subclavian artery in the great Dane, resulted in resolution of clinical signs in both of the dogs in this report.  相似文献   
59.
Two groups of naive heifers were given primary courses of two inactivated bovine viral diarrhoea (BVD) virus vaccines licensed for use in the UK. Their humoral responses in serum and milk were assayed by means of an indirect ELISA detecting antibodies to structural viral glycoproteins, a blocking ELISA specific for antibodies to the non-structural protein NS2-3 and the virus neutralisation test (VNT). For each assay, the numbers of serum or milk samples testing positive at each sample point and the mean values were determined. In both vaccine groups, serum antibody responses were detected by the indirect ELISA and the VNT, with both the numbers of seropositive animals and mean values peaking five weeks after the second vaccination. In the 23 heifers vaccinated with Bovilis BVD, the mean NS2-3-specific ELISA values remained low throughout the trial, with no serum or milk samples testing positive. In the 24 heifers vaccinated with Bovidec, the mean NS2-3 responses peaked below the level of positivity five weeks after the second vaccination, before declining again; NS2-3-specific antibodies were detected in one serum sample and one milk sample from two heifers in this group. A pooled milk sample from each vaccine group tested negative by both ELISAS 12 weeks after the second vaccination.  相似文献   
60.
Background: Fecal α1‐proteinase inhibitor (α1‐PI) clearance is a reliable, noninvasive marker for protein‐losing enteropathy (PLE) in human beings. An assay for measurement of this protein in the dog has been developed and validated and may be useful for the investigation of gastrointestinal disease in this species. Nonsteroidal anti‐inflammatory drugs (NSAIDs) frequently are administered to dogs and may have adverse effects on the gastrointestinal tract, including gastroduodenal ulceration and altered mucosal permeability. The value of fecal α1‐PI measurement in detecting unrelated gastrointestinal disease may be limited in dogs on NSAID therapy, but α1‐PI may be a useful marker for NSAID‐induced gastrointestinal damage. Objective: The aim of this study was to evaluate the effects of long‐term administration of NSAIDs on fecal α1‐PI concentrations in dogs. Methods: Fecal samples were collected from 2 groups of dogs: 1) 21 clinically‐healthy client‐owned dogs without signs of gastrointestinal disease and receiving no NSAIDs and 2) 7 dogs referred for investigation and treatment of orthopedic disorders; the dogs had received either meloxicam or carprofen daily for at least 30 days. Fecal α1‐PI concentration was measured by ELISA. Results: Fecal α1‐PI concentrations, expressed as μg/g of feces, were not significantly different between groups 1 and 2 (median [range], group 1: 9.9 μg/g [0.0–32.1 μg/g]; group 2: 5.6 μg/g [1.1–32.3 μg/g]; P= .81). Conclusions: These results suggest that use of cyclooxygenase‐2‐selective NSAIDs, such as carprofen and meloxicam, does not significantly affect fecal α1‐PI measurements. However, study numbers were small, and larger prospective trials are required to assess more accurately the gastrointestinal effects of NSAIDs in dogs.  相似文献   
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