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351.
Three Gyps vulture species are on the brink of extinction in South Asia owing to the veterinary non-steroidal anti-inflammatory drug (NSAID) diclofenac. Carcasses of domesticated ungulates are the main food source for Asia''s vultures and birds die from kidney failure after consuming diclofenac-contaminated tissues. Here, we report on the safety testing of the NSAID ketoprofen, which was not reported to cause mortality in clinical treatment of scavenging birds and is rapidly eliminated from livestock tissues. Safety testing was undertaken using captive non-releasable Cape griffon vultures (Gyps coprotheres) and wild-caught African white-backed vultures (G. africanus), both previously identified as susceptible to diclofenac and suitable surrogates. Ketoprofen doses ranged from 0.5 to 5 mg kg−1 vulture body weight, based upon recommended veterinary guidelines and maximum levels of exposure for wild vultures (estimated as 1.54 mg kg−1). Doses were administered by oral gavage or through feeding tissues from cattle dosed with ketoprofen at 6 mg kg−1 cattle body weight, before slaughter. Mortalities occurred at dose levels of 1.5 and 5 mg kg−1 vulture body weight (within the range recommended for clinical treatment) with the same clinical signs as observed for diclofenac. Surveys of livestock carcasses in India indicate that toxic levels of residual ketoprofen are already present in vulture food supplies. Consequently, we strongly recommend that ketoprofen is not used for veterinary treatment of livestock in Asia and in other regions of the world where vultures access livestock carcasses. The only alternative to diclofenac that should be promoted as safe for vultures is the NSAID meloxicam.  相似文献   
352.
This study assesses the effects of daily beta-hydroxy beta-methylbutyrate (HMB) supplementation on muscular strength (bench press, squats, and power cleans) and body composition (body weight and body fat) among collegiate football players undergoing a strenuous exercise program. Subjects were collegiate football players (n = 35) training under the supervision of certified strength coaches averaging 20 hours of weekly exercise. In the first supplementation period, 16 of the 35 subjects were supplemented with 3 g of HMB per day for 4 weeks; the other 19 received a placebo followed by a 1-week washout period and then a second supplementation period in a randomized double-blind crossover, placebo design. There were no significant changes (p > 0.05) in muscular strength, including bench press, squats, and power cleans, among the subjects. There were also no significant changes (p > 0.05) in body composition, including body fat and body weight. Very little clinical evidence exists for supplementing HMB in athletic populations.  相似文献   
353.
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355.

Intro

Binge eating disorder (BED) affects 3.5% of the population and is characterized by binge eating for at least 2 days a week for 6 months. Treatment options include cognitive behavioral therapy, interpersonal psychotherapy, and pharmacotherapy which are associated with varied success.Little is known about the biology of BED. Since there is evidence that the insulin like growth factor system is implicated in regulation of body weight, insulin sensitivity and feeding behavior, we speculated it may be involved in BED.

Methods

A cross-sectional comparison was made between three groups of women: overweight with BED, overweight without BED and normal weight without BED. Women were assigned to Group Psychodynamic Interpersonal Psychotherapy. Blood was collected before therapy, at completion and at 6months follow up for evaluation of IGF-II using Western blot.

Results

97 overweight women with BED contributed to the cross-sectional comparison. The two control groups comprised 53 overweight women without BED, and 50 age matched normal weight women without BED. Obese women had significantly lower Big IGF-II than normal weight women, p = .028; Overweight women with BED had higher Mature IGF-II than normal weight women, p<.05.Big IGF-II showed a significant decreasing slope from pre- to post- to six months post-group psychological treatment, unrelated to changes in BMI (p = .008).

Conclusion

Levels of IGF-II isoforms differed significantly between overweight and normal weight women. Overweight women with BED display abnormal levels of circulating IGF-II isoforms. BED is characterized by elevated mature IGF-II, an isoform shown to carry significant bioactivity. This finding is not related to BMI or to changes in body weight. The results also provide preliminary evidence that BIG IGF-II is sensitive to change due to group psychological treatment. We suggest that abnormalities in IGF-II processing may be involved in the neurobiology of BED.  相似文献   
356.
The HIRIP3 protein had been identified from its interaction with the HIRA histone chaperone. Experiments using anti-peptide antisera indicated that this 556-aa protein is nuclear throughout the cell cycle and excluded from condensed chromatin during mitosis. Based on its electrophoretic migration and sensitivity to phosphatase treatment, endogenous HIRIP3 was found to be heavily phosphorylated. HIRIP3 can be phosphorylated in vitro by a recombinant form of the serine-threonine kinase CK2. Moreover, HIRIP3 protein was found to co-purify with a CK2 activity. Together, these data prompt us to propose HIRIP3 as a new member of the growing list of CK2 substrates with a possible role in chromatin metabolism.  相似文献   
357.
Moraxella bovis is the causative agent of infectious bovine keratoconjunctivitis (IBK) also known as pinkeye, a highly contagious and painful eye disease that is common in cattle throughout the world. Vaccination appears to be a reasonable and cost-effective means of control of pinkeye. Identification of genes encoding novel secreted antigens have been reported, and these antigens are being assessed for use in a vaccine. One of the genes encodes phospholipase B, which can be expressed with high purity and yield in recombinant Escherichia coli as a secreted, soluble, non-tagged, mature construct (less signal peptide with predicted mass 63 kDa). The recombinant phospholipase B exhibited anomalous electrophoretic mobility that was dependent on the temperature of the denaturing process, with bands observed at either 52 or 63 kDa. Analysis by in-gel digestion and liquid chromatography-mass spectrometry revealed these two distinct forms most likely had identical sequences. Phospholipase B is a compact, globular protein with a predicted structure typical of a conventional autotransporter. It is suggested that high temperature is required to unfold the protein (to denature the beta-barrel-rich transporter domain) and to ensure accessibility of the reducing agent. Interestingly, the two forms of the enzyme, differing in size and isoelectric points, were also detected in cell-free supernatants of M. bovis cultures, indicating that native phospholipase B may exist in two differentially folded states possibly also differing in oxidation status of cysteine residues.  相似文献   
358.
The Cape hake species, Merluccius capensis and Merluccius paradoxus are the most important resource of the South African and Namibian demersal fishery, but it is unclear whether there is a single population of each shared by both countries. We analysed the population structure and evolutionary history of these two species using the variable 5' region of the mtDNA control region for 311 specimens of M. capensis and 333 specimens of M. paradoxus sampled between Lüderitz (southern Namibia) to south of Cape Point (South Africa). 107 haplotypes for M. capensis and eight haplotypes for M. paradoxus were recovered. AMOVA and pairwise Phi(st) analyses revealed no structure in M. capensis, however significant genetic differentiation between Namibian and South African 'populations' was detected for M. paradoxus. This was only restricted to mature fish older than 3 and 4 years and not for juvenile fish younger than 3 years. Analyses reveal that M. capensis has undergone population expansion (Fu's Fs=-26.65, P<0.001), possibly within the last 4500-23,000 years, whereas M. paradoxus has not. Our study highlights the utility of genetic markers to unravel the evolutionary history of sympatric species, as well as addressing management issues within regions where commercially valuable fish stocks are shared between nations.  相似文献   
359.
Diversity in the mechanisms of neuronal cell death   总被引:40,自引:0,他引:40  
Yuan J  Lipinski M  Degterev A 《Neuron》2003,40(2):401-413
Neurons may die as a normal physiological process during development or as a pathological process in diseases. The best-understood mechanism of neuronal cell death is apoptosis, which is regulated by an evolutionarily conserved cellular pathway that consists of the caspase family, the Bcl-2 family, and the adaptor protein Apaf-1. Apoptosis, however, may not be the only cellular mechanism that regulates neuronal cell death. Neuronal cell death may exhibit morphological features of autophagy or necrosis, which differ from that of the canonical apoptosis. This review evaluates the evidence supporting the existence of alternative mechanisms of neuronal cell death and proposes the possible existence of an evolutionarily conserved pathway of necrosis.  相似文献   
360.
Protein arginine methyltransferase (PRMT) 8 is unique among the PRMTs, as it has a highly restricted tissue expression pattern and an N terminus that contains two automethylation sites and a myristoylation site. PRMTs catalyze the transfer of a methyl group from S-adenosylmethionine (AdoMet) to a peptidylarginine on a protein substrate. Currently, the physiological roles, regulation, and cellular substrates of PRMT8 are poorly understood. However, a thorough understanding of PRMT8 kinetics should provide insights into each of these areas, thereby enhancing our understanding of this unique enzyme. In this study, we determined how automethylation regulates the enzymatic activity of PRMT8. We found that preventing automethylation with lysine mutations (preserving the positive charge of the residue) increased the turnover rate and decreased the Km of AdoMet but did not affect the Km of the protein substrate. In contrast, mimicking automethylation with phenylalanine (i.e. mimicking the increased hydrophobicity) decreased the turnover rate. The inhibitory effect of the PRMT8 N terminus could be transferred to PRMT1 by creating a chimeric protein containing the N terminus of PRMT8 fused to PRMT1. Thus, automethylation of the N terminus likely regulates PRMT8 activity by decreasing the affinity of the enzyme for AdoMet.  相似文献   
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