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1.
Both dauer formation (a stage of developmental arrest) and adult life-span in Caenorhabditis elegans are negatively regulated by insulin-like signaling, but little is known about cellular pathways that mediate these processes. Autophagy, through the sequestration and delivery of cargo to the lysosomes, is the major route for degrading long-lived proteins and cytoplasmic organelles in eukaryotic cells. Using nematodes with a loss-of-function mutation in the insulin-like signaling pathway, we show that bec-1, the C. elegans ortholog of the yeast and mammalian autophagy gene APG6/VPS30/beclin1, is essential for normal dauer morphogenesis and life-span extension. Dauer formation is associated with increased autophagy and also requires C. elegans orthologs of the yeast autophagy genes APG1, APG7, APG8, and AUT10. Thus, autophagy is a cellular pathway essential for dauer development and life-span extension in C. elegans.  相似文献   
2.
Objective— To report surgical planning, technique, and outcome of custom total knee replacement (TKR) performed to manage a medial femoral condylar nonunion in a dog.
Study Design— Clinical case report.
Animal— A 3-year-old, 20 kg Karelian Bear Hound.
Methods— Computed tomographic scan of the left pelvic limb was used to build a stereolithography model of the distal portion of the femur. The model was used to create a custom augment to replace the missing medial femoral condyle and a custom stem for intramedullary condylar cemented fixation. The augment and stem were adapted to femoral and tibial components already available. The model was used to rehearse the surgery and then the custom prosthesis was implanted.
Results— Weight bearing returned 8 hours after surgery and improved thereafter. Joint alignment was normal and prosthetic joint motion was 60–165° postoperatively. The dog resumed moose hunting 3 months after surgery. Peak vertical force and impulse of the operated limb measured 17 months after surgery were 65% and 47% of the normal, contralateral limb.
Conclusion— Based on short-term follow-up, cemented canine TKR was successfully achieved for management of a severely abnormal stifle joint.
Clinical Relevance— With further refinement and development of commercially available prostheses, TKR should be possible for canine patients.  相似文献   
3.
A 27-kg German Shorthaired Pointer was referred for evaluation due to the complaint of left pelvic limb lameness and signs of pain in the left stifle joint. Radiographs revealed signs of a healed supracondylar femoral fracture that had been previously repaired at another hospital with an intramedullary pin and two cross pins. In addition, there were signs of severe osteoarthritis (OA). The OA had been managed medically with administration of carprofen and nutraceuticals for nine months without any improvement. Left total knee replacement (TKR) surgery was performed to alleviate signs of pain. The patient was assessed preoperatively and at six months, one year, and two years after surgery using radiology, force platform analysis of gait, thigh circumference measures, goniometry, and lameness evaluation. Following surgery, the dog resumed normal activity without any signs of pain and a good quality of life at 3.5 months. Force plate analysis found that peak vertical force on the TKR limb was 85.7% of the normal contralateral limb after two years. Total knee replacement was a successful treatment to manage knee OA associated with a healed distal femoral fracture and internal fixation in this dog.  相似文献   
4.
OBJECTIVE: To study gelatinolytic matrix metalloproteinases (MMPs) in tracheobronchial lavage fluid (TBLF) obtained from clinically normal calves and calves with Pasteurella multocida infection. SAMPLE POPULATION: Samples of TBLF obtained from 11 calves with clinical signs of respiratory tract disease and growth of P multocida and Mycoplasma spp during culture of TBLF and samples of TBLF from 6 clinically normal calves with no bacterial growth during culture of TBLF. PROCEDURE: MMPs in TBLF were analyzed by use of gelatin zymography. Gelatinases were identified on the basis of molecular weights and inhibition by EDTA. RESULTS: The main gelatinolytic MMPs detected were the proform (90 to 110 kd) and active form (75 to 85 kd) of MMP-9 (gelatinase B) and the proform (67 to 75 kd) and active form (< 65 kd) of MMP-2 (gelatinase A). Increased amounts of active MMP-2 and MMP-9 were detected in TBLF of calves with respiratory tract disease, compared with amounts of active MMP-2 and MMP-9 in TBLF of clinically normal calves. Concurrent infection with Mycoplasma bovirhinis in calves with pneumonia attributable to P multocida was associated with higher concentrations of MMP-9. CONCLUSIONS AND CLINICAL RELEVANCE: The host response to P multocida includes increases in MMP-2 and MMP-9 concentrations in TBLF. Greater amounts of MMPs detected in calves with concurrent M bovirhinis and P multocida infection indicates synergism between these organisms.  相似文献   
5.
Since formalin is widely used in prevention of Saprolegnia infections in salmonid fish hatcheries, there is a need for more environmentally safe treatment methods. Therefore, we screened 360 bacterial isolates against their ability to antagonize the growth of Saprolegnia parasitica hyphae in vitro, and best strains were selected according to their antagonistic properties and colonization capability on rainbow trout egg surface. Protective bacterial cultures of Pseudomonas sp. M162, Pseudomonas sp. M174 and Janthinobacterium M169 were tested for prevention of Saprolegnia sp. infections during incubation trials of rainbow trout (Oncorhynchus mykiss) eggs with UV irradiated (400 mWs cm?2) and non‐treated inlet water. UV irradiation of inlet water significantly decreased mortality during the incubation. Lowest mortalities were observed in protective culture treated groups incubated with UV‐irradiated inlet water. UV irradiation increased the dominance of the main bacterial colonizers and variation in the bacterial species diversity between the experimental units.  相似文献   
6.
Inhibitory concentrations of clove oil and ethanol against growth of Saprolegnia sp. hyphae were screened by a modification of the hemp (Cannabis sativa L.) seed MicroPlate (HeMP) method and their usability as antifungal agents during incubation of rainbow trout Oncorhynchus mykiss eggs was tested. In vitro experiment showed that in continuous static exposure, clove oil at 100 mg L?1 significantly inhibited the growth of Saprolegnia, whereas in bath exposures, clove oil at 500 mg L?1 had no significant effect at any exposure time tested (15, 60 and 240 min), but clove oil at 10 000 mg L?1 significantly inhibited growth at all exposure times. Clove oil and ethanol treatments had no visible effects on the onset or spread of the fungus during incubation of rainbow trout eggs. Clove oil at 1000 mg L?1 resulted in 95–100% mortality before the eyed stage was reached. Sublethal concentrations of clove oil and ethanol had no effects on the development rate of the embryo or growth and yolk utilization efficiency after hatching. This study suggests that clove oil and ethanol may not be options in controlling aquatic fungi infestations during incubation of rainbow trout eggs.  相似文献   
7.
Quantitative and qualitative high-performance liquid chromatographic methods were utilized to separate phospholipid classes. After qualitative separation, the fatty acid moieties of each separated phospholipid class were determined using a gas chromatographic method. On the basis of these analyses, the effect of supplemented feeds on hen egg yolk lipids can be evaluated. The supplemented feeds contained 1-5% of vegetable-based or fish oils. The phospholipid content and composition were the same in all feeding groups, the proportions of phosphatidylcholines, phosphatidylethanolamines, and sphingomyelins being 70, 28, and 3%, respectively. In each feeding group, the fatty acid profiles of phosphatidylcholines and sphingomyelins were similar to each other and different from that of phosphatidylethanolamines. The supplemented feeds had a statistically significant (p < 0.05) effect on the fatty acid composition of phosphatidylcholines. The supplements decreased the proportion of saturated fatty acids in total fat, but this effect was not found in phospholipids.  相似文献   
8.
Two-year-old Norway spruce (Picea abies (L.) Karst) seedlings were exposed to trafficemissions along roadsides with three different trafficdensities and speed limits; highway, street and aquiet local road. Deposition of the polyaromatichydrocarbons (PAH) was determined at all sites usingmoss bags as an indicator of organic traffic pollutantdeposition. Short term concentrations of atmosphericnitrogen oxides (NOx) and aerosol black carbon(BC) were also recorded from the sites. The responsesof the needle epicuticular wax structure of theexposed spruce seedlings were analysed under thescanning electron microscopy (SEM). The epistomatalwax structure of needles was distinctively fused andaggregated along the highway and street withrelatively high traffic densities. Along the localroad, where the traffic density was low, nosignificant degradation of needle epicuticular wax wasobserved. The NOx and BC data, along with PAHsaccumulated in moss bags indicate significantdeposition of gaseous pollutants and particulateorganic compounds along the highway and street andthese are suggested as cause of the epicuticular waxdegradation. Epistomatal wax structure is thus suggested to be an early indicator of traffic exposure effects.  相似文献   
9.
Ovomucin was fractionated from whole egg albumen, thick egg albumen, liquid egg albumen, and a liquid egg albumen filtration byproduct by using the isoelectric precipitation method. The amounts of ovomucin measured in the above-mentioned fractions were 280, 340, 500, and 520 mg per 100 g of albumen, respectively. There was great variation between the beta-ovomucin contents of the different albumen fractions. Whole egg albumen contained about 25 mg of beta-ovomucin in 100 g of albumen, whereas thick egg albumen, liquid egg albumen, and the filtration byproduct contained about 1.5, 3, and 5 times more beta-ovomucin, respectively, as compared to whole egg albumen. The results indicate that both the liquid egg albumen fraction and especially the filtration byproduct fraction appear to be potential sources of ovomucin when it is used as an ingredient for functional foods.  相似文献   
10.
Sieving as an effluent treatment method for aquaculture   总被引:1,自引:0,他引:1  
A new device designed for sieving of fish farm effluent (trademark Triangel Filter TF 2400) was tested in order to prove if such an apparatus may be used instead of the swirl concentrator. The phosphorus reduction was estimated by water sampling and phosphorus budget and by measuring the phosphorus content in flushing water and in settled sludge.

Sieving is a promising and useful method to treat aquaculture effluent, especially in ‘high-tech’ systems (recirculation, warmed water facilities) where high effluent quality and the most effective removal of solids is needed.  相似文献   

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