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101.
Yong-Gang Nie Ze-Jun Zhang Ronald R. Swaisgood Fu-Wei Wei 《European Journal of Wildlife Research》2012,58(1):235-241
In the first-ever study of reproductive endocrinology in wild male giant pandas (Ailuropoda melanoleuca), we provide new insights into the reproductive ecology of the species. We tracked and observed pandas in Foping Nature Reserve
of the Qinling Mountains for 3 years, collecting fecal samples for testosterone metabolite analysis and data on reproductive
activity. Males encountered multiple potential mates and competed for reproductive access to females. Male testosterone metabolites
increased in February, peaked in March and April, and fell back to baseline after the mating season. However, males did not
maintain a high testosterone level throughout the mating season. Male testosterone instead peaked during encounters with potential
mates and declined between encounters. These results indicate that testicular activity is typically dormant until mobilized
by interactions with females and potentially by interactions with male competitors. This suggests that male pandas may be
energetically constrained, elevating testosterone levels only when necessary to meet the demands of intrasexual competition
and courtship and fertilization of females. Maintaining a high testosterone level is metabolically expensive and male pandas
enter the mating season during a period of low food availability. If this hypothesis is correct, male panda body condition
may be an important determinant of reproductive outcome, and anthropogenic activities that diminish foraging resources may
have significant impacts on the mating ecology of the species, affecting its conservation. 相似文献
102.
1,2-Dibromoethane and glycidol are well known genotoxic carcinogens, which have been widely used in industry. To identify
a specific biomarker for these carcinogens in cells, the cellular proteome of L5178Y mouse lymphoma cells treated with these
compounds was analyzed by 2-dimensional gel electrophoresis (2-DE) and MALDI-TOF mass spectrometry (MS). Of 50 protein spots
showing a greater than 1.5-fold increase or decrease in intensity compared to control cells on a 2-D gel, we focused on the
candidate biomarker moesin. Western analysis using monoclonal rabbit anti-moesin confirmed the identity of the protein and
its increased level of expression upon exposure to the carcinogenic compounds. Moesin expression also increased in cells treated
with six additional genotoxic carcinogens, verifying that moesin could serve as a biomarker to monitor phenotypic change upon
exposure to genotoxic carcinogens in L5178Y mouse lymphoma cells. 相似文献
103.
104.
Ou Wang Chunyan Wang Min Nie Quancai Cui Heng Guan Yan Jiang Mei Li Weibo Xia Xunwu Meng Xiaoping Xing 《PloS one》2012,7(9)
Objective
It is widely recognized that the diagnosis of parathyroid carcinoma (PC) is often difficult because of the overlap of characteristics between malignant and benign parathyroid tumors, especially at an early stage. Based on the identification of tumor suppressor gene HRPT2/CDC73 and its association with hereditary and sporadic PC, screening of gene mutations and detection of parafibromin immunoreactivity have been suggested as diagnostic instruments of PC in Whites. There is little information about HRPT2/CDC73 mutations and its corresponding protein expression in patients with sporadic PC in Chinese population, and the long-term follow-up data is scarce.Methods
Paraffin-embedded tissues were obtained from 13 patients with PC, 13 patients with parathyroid adenoma (PA) and 7 patients with parathyroid hyperplasia(PH), and 6 normal parathyroid (NP) tissues as controls. Peripheral blood from 11 patients with PC was collected. PCR products using Genomic DNA extracted from tumor tissues or blood as template was sequenced for HRPT2/CDC73 gene. Expression of parafibromin in tumor tissues was evaluated by immunohistochemical analysis.Results
Six mutations in 6 of 13 patients with PC were identified, with three being novel. Four of them were germ-line mutations. Patients with mutations were susceptible to recurrence of the PC. Complete (8/13, 61.5%) or partial (5/13, 38.5%) loss of parafibromin expression was observed in PC tissues. All of tissue samples from normal parathyroid or benign parathyroid tumors displayed positive immunostaining of parafibromin except one adenoma.Conclusions
The present study supplies information on the mutations and protein expression of HRPT2/CDC73 gene and phenotypes of parathyroid carcinoma in Chinese population. And the expanded mutation database of this gene may benefit patients in the diagnosis and treatment of this disease. 相似文献105.
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108.
Polymorphum gilvum SL003B-26A1(T) is the type strain of a novel species in the recently published novel genus Polymorphum isolated from saline soil contaminated with crude oil. It is capable of using crude oil as the sole carbon and energy source and can adapt to saline soil at a temperature of 45°C. The Polymorphum gilvum genome provides a genetic basis for understanding how the strain could degrade crude oil and adapt to a saline environment. Genome analysis revealed the versatility of the strain for emulsifying crude oil, metabolizing aromatic compounds (a characteristic specific to the Polymorphum gilvum genome in comparison with other known genomes of oil-degrading bacteria), as well as possibly metabolizing n-alkanes through the LadA pathway. In addition, COG analysis revealed Polymorphum gilvum SL003B-26A1(T) has significantly higher abundances of the proteins responsible for cell motility, lipid transport and metabolism, and secondary metabolite biosynthesis, transport and catabolism than the average levels found in all other genomes sequenced thus far, but lower abundances of the proteins responsible for carbohydrate transport and metabolism, defense mechanisms, and translation than the average levels. These traits support the adaptability of Polymorphum gilvum to a crude oil-contaminated saline environment. The Polymorphum gilvum genome could serve as a platform for further study of oil-degrading microorganisms for bioremediation and microbial-enhanced oil recovery in harsh saline environments. 相似文献
109.
110.
The depleting petroleum reserve, increasingly severe energy crisis, and global climate change are reigniting enthusiasm for seeking sustainable technologies to replace petroleum as a source of fuel and chemicals. In this paper, the efficiency of the MVA pathway on isoprene production has been improved as follows: firstly, in order to increase MVA production, the source of the "upper pathway" which contains HMG-CoA synthase, acetyl-CoA acetyltransferase and HMG-CoA reductase to covert acetyl-CoA into MVA has been changed from Saccharomyces cerevisiae to Enterococcus faecalis; secondly, to further enhance the production of MVA and isoprene, a alanine 110 of the mvaS gene has been mutated to a glycine. The final genetic strain YJM25 containing the optimized MVA pathway and isoprene synthase from Populus alba can accumulate isoprene up to 6.3 g/L after 40 h of fed-batch cultivation. 相似文献