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Lysine acetylation is an important posttranslational modification (PTM) that regulates the function of proteins by affecting their localization, stability, binding, and enzymatic activity. Aberrant acetylation patterns have been observed in numerous diseases, most notably cancer, which has spurred the development of potential therapeutics that target acetylation pathways. Mass spectrometry (MS) has become the most adopted tool not only for the qualitative identification of acetylation sites but also for their large-scale quantification. By using heavy isotope labeling in cell culture combined with MS, it is now possible to accurately quantify newly synthesized acetyl groups and other PTMs, allowing differentiation between dynamically regulated and steady-state modifications. Here, we describe MS-based protocols to identify acetylation sites and quantify acetylation rates on both proteins in general and in the special case of histones. In the experimental approach for the former, 13 C-glucose and D 3 -acetate are used to metabolically label protein acetylation in cells with stable isotopes, thus allowing isotope incorporation to be tracked over time. After protein extraction and digestion, acetylated peptides are enriched via immunoprecipitation and then analyzed by MS. For histones, a similar metabolic labeling approach is performed, followed by acid extraction, derivatization with propionic anhydride, and trypsin digestion prior to MS analysis. The procedures presented may be adapted to investigate acetylation dynamics in a broad range of experimental contexts, including different cell types and stimulation conditions.

To understand the factors influencing tree radial growth, we analyzed the seasonal dynamics of tree growth of 3 common species (Pinus koraiensis, Tilia amurensis, Quercus mongolica), compared interspecific growth rates and explored the effects of size, neighborhood competition, soil and topography based on five years dendrometer bands monitoring data of the 3 common species in a broad-leaved Korean pine (P. koraiensis) mixed forest plot in Changbai Mountain, Northeast China. The results showed that the growth dynamics of 3 species were consistent. Trees began to grow in late May, thrived in July, grew at declining rates from late August and stopped growing in late October. Annual relative growth rates were significantly different among the species. Q. mongolica tended to grow faster than the other two species, and the differences of growth rates among the 3 species were especially large for small and medium trees. Tree growth rates of P. koraiensis and Q. mongolica were strongly decreased by neighborhood competition, while tree growth rate of T. amurensis was significantly related to tree size, soil and topography.

Spruce-fir forest is the best protected forest vegetation, while larch forest is intrazonal vegetation on the northern slope of Changbai Mountains. To further understand their species composition and community structure, we established a 4 hm2 forest permanent plot in each of these two forests in 2010. All free-standing plant species with DBH (diameter at breast height) ≥ 1 cm were mapped, tagged, and identified to species. The results showed that there were 9257 stems belonging to 8640 genotype individuals, 22 species, 6 genera and 12 families in the spruce-fir forest plot, while 4060 stems belonging to 3696 genotype individuals, 22 species, 8 genera and 16 families in the larch forest plot. Species composition in the two plots was very similar. Most of the species belonged to the Changbai Mountains plant flora. The analysis of species' importance values showed that there were dominant species in both communities. The spruce-fir forest was dominated by Abies nephrolepis and Larix olgensis, whose importance values accounted for 38.7% and 23.9% of the sum of importance values over all species in the plot, respectively. The larch forest was dominated solely by L. olgensis, whose importance value accounted for 61.9% of the sum of importance values over all species in the plot. Both forests were in good condition of regeneration and showed a reversed 'J' type in tree size distributions, at community level. However, different species showed different shapes in size distribution in the two forests. A. nephrolepis showed a reversed 'J' type size distribution in the spruce-fir forest, while L. olgensis with DBH ≥ 10 cm showed a hump-shaped distribution in the larch forest. Spatial distribution patterns of the main species changed differently with size class and spatial scales. Common species had different spatial distribution patterns in the two plots.

The broad-leaved Korean pine mixed forest represents the typical vegetation type of the eastern mountain area in Northeast China. However, due to the interference of human activities, the natural broad-leaved Korean pine forest only distributes in some residual fragments with unequal areas in Changbai Mountains and Small Hinggan Mountains. To compare and analyze the similarities and differences of broad-leaved Korean pine mixed forests in the different areas, we established six forest plots following the field protocol of the 50 hm2 forest plot in Panama (Barro Colorado Island, BCI) in 2012 in Changbai Mountain National Nature Reserve in Jilin Province and the eastern mountain area in Liaoning Province. All free-standing plant species with DBH (diameter at breast height) > or = 1 cm were mapped, tagged and identified to species. The results showed that there were 69 woody species in the six plots, comprising 42 genera and24 families. Aceraceae was the most species-rich family in all six plots. Most species belonged to the plant type of North Temperate Zone, with a minor subtropical plant species component. The statistics of species abundance, basal area, mean DBH, and importance value showed that there were obviously dominant species in each community. The DBH distribution of all individuals showed a reversed "J" type. However, the percentage of individuals in small size-class and large size-class varied in the six communities, which indicated that these communities were at different successional stages. Ranked by the importance value, the DBH distribution of the top three species in the six plots showed four distribution types: reversed "J" distribution, reversed "L" distribution, unimodal distribution, and partial peak distribution. Spatial distribution patterns of the main species in the six plots changed differently with species and size-class, and the distribution patterns of the same species varied in the different plots.

Objective: To investigate the discrepancy of anorectal function in patients of Parkinson's disease (PD) with constipation and functional constipation (FC)., Methods: Fifteen consecutive male PD patients with constipation and 45 male FC patients were recruited for the study. All subjects underwent colonoscopy or barium enema in order to exclude organic colon diseases. Every patient underwent anorectal manometry and was categorized into subgroups of either dyssynergia defecation (F3a) or inadequate defecatory propulsion (F3b)., Results: The ages of PD with constipation and FC patients were (70 ± 11) and (68 ± 11) years old respectively. The rectal resting pressure in PD with constipation was higher than that in FC group without statistical significance [9.0(4.0, 15.0) mm Hg vs 6.0(3.0, 9.5) mm Hg, P = 0.082, 1 mm Hg = 0.133 kPa]. The anal resting pressure in PD group was not different from FC group [(51.2 ± 17.2) mm Hg vs (59.7 ± 20.4) mm Hg, P = 0.152]. During anal squeezing, the maximal contraction pressure and area under the squeeze curve in PD with constipation group were both significantly lower than FC patients [maximal contraction pressure: (136.9 ± 43.8) mm Hg vs (183.0 ± 62.1) mm Hg, P = 0.010; area under the squeeze curve: (823.5 ± 635.7) mm Hg·s vs (1392.4 ± 939.9) mm Hg·s, P = 0.033]. During forced defecation, both of the defecation rectal pressure and defecation anal pressure in PD with constipation group were significantly lower than that of FC patients [22.0(15.0, 30.0) vs 42.0(31.0, 55.0) mm Hg, P = 0.000; and (46.3 ± 23.3) vs (77.9 ± 35.1) mm Hg, P = 0.002]. The proportions of F3a subtype were 10/15 and 46.7% (21/45) in PD with constipation and FC patients respectively. There was no significant difference in the constituent ratio (P = 0.120). Initial rectal sensory volumes were (91.3 ± 56.9) ml and (67.2 ± 38.9) ml in PD with constipation and FC patients respectively. Even both volumes were higher than the normal controls, there was no significant difference between the two groups (P = 0.074)., Conclusions: Both PD with constipation and FC patients have abnormal anorectal motility and sensation comparing to the FC group, the parameters of anal contraction and defecation are significantly lower, F3b is dominant, and rectal sensory threshold is higher in PD with constipation patients. These parameters could possibly characterize the anorectal manometry for PD with constipation patients, which is helpful to understand the pathogenesis of PD and differentiate from other diseases.

Taking the 5 hm2 sampling plot in the natural secondary poplar-birch forest in Changbai Mountains as test object, and based on the two census data in 2005 and 2010, an analysis was made on the main tree species composition and quantity, size class distribution of dead individuals, and regeneration characteristics of the main tree species in different habitat types of the plot in 2005-2010. In the five years, the species number of the individuals with DBH> or = 1 cm increased from 46 to 47, among which, 3 species were newly appeared, and 2 species were disappeared. The number of the individuals changed from 16509 to 15027, among which, 2150 individuals died, accounting for 13% of the whole individuals in 2005, and 668 individuals were newly increased. The basal area of the trees increased from 28.79 m2.m-2 to 30.55 m2.m-2, with that of 41 species increased while that of 6 species decreased. The decrease of the basal area of Betula platyphylla and Populus davidiana accounted for 72.3% of the total decrease. Small individuals had higher mortality, as compared with large ones, and the mortality of the individuals with DBH<5 cm occupied 65% of the total. B. platyphylla and P. davidiana contributed most in the dead individuals with large DBH. No difference was observed in the tree mortality among different habitat types, but the mortality of the individuals with different size classes showed greater variation.

In order to understand the composition and spatiotemporal dynamics of the litter falls at community level in a broad-leaved Korean pine mixed forest in Changbai Mountains, litter falls were collected from 150 containers in a 25 hm2 permanent plot in 2008. The leaf litters in the containers were from 35 tree species, accounting for 67.3% of the total number (52) of the tree species with DBH > or =1 cm in the plot. The litter falls had a weight 29.39 kg, equivalent to 3918.4 kg x hm(-2) among which, broad leaves, miscellany, needle leaves, and branches occupied 61.7%, 18.0%, 11.7%, and 8.6%, respectively. About 83.8% of the broad leaves were from Tilia amurensis, Fraxinus mandshurica, Quercus mongolica, Acer mono, and Ulmus japonica. The litter falls showed an evident seasonal dynamics, with the peaks occurred from 13 September to 10 October, e.g., the litter falls from T. amurensis and Pinus koraiensis peaked in 13-26 September, while those from Q. mongolica, U. japonica, and A. pseudo-sieboldianum peaked in 27 September to 10 October. There was a great difference in the mass of the litter falls among the containers, e.g., with 150-200 g litters in 68 containers and >500 g litters in 1 container. The species number of the litter falls in a container was 18 in maximum, and was 12 in common (32 containers). Litter falls mass was positively proportional to the sum of the basal area at breast height of parent trees in the plot, and the amount of the litter falls in the containers was related with the locations of the containers, exhibiting an evident spatial heterogeneity in the plot.

Based on the shrub census of 600 quadrats (5 mx5 m) in a 25 hm2 plot of broad-leaved Korean pine mixed forest in Changbai Mountains, this paper analyzed the species composition, structure, and spatial distribution of shrubs in the forest. A total of 18 shrub species, including 6435 shrub individuals and 11369 stems, were found in the census, with Philadelphus schrenkii, Corylus mandshurica, and Acer barbinerve being the dominant species. P. schrenkii had the highest amounts of individuals and stems, occupying 40.6% and 33.4% of the total, respectively. There existed great differences in the clumpy ratio, stem number per clump, crown size, and basal diameter among the shrub species, and the height of different shrub species also varied significantly, with obvious vertical stratification observed in the community. The dominant species P. schrenkii had a wide distribution, while Sorbaria sorbifolia, Spiraea chamaedryfolia, S. salicifolia, and Euonymus pauciflorus had obvious heterogeneous distributions.

Mycoplasma hyopneumoniae colonizes at the porcine respiratory-ciliated epithelial cells and causes the enzootic pneumonia of swine. The adhesion step is crucial in the colonization process. A few adhesion molecules have been characterized, and the concurrent receptors from the porcine ciliated cells have also been suggested to recognize the adhesion molecules. In the present study, the interactions between M. hyopneumoniae and porcine tracheal ciliated cells were investigated by employing the Far-Western blotting method. The results indicate that aconitase, lamin A/C, and peroxiredoxin of the porcine tracheal ciliated cell may interact specifically with the mycoplasmal proteins. We speculate that these mycoplasmal proteins could be secreted cleavage products, and their relative small size may enable them to penetrate into ciliated cells interfering with important metabolic pathways and other critical cellular processes.

Mycoplasma hyopneumoniae is an important pathogen of pigs causing enzootic pneumonia of swine. The pathogen remains largely enigmatic as far as the host-pathogen interactions are concerned. In the present study, the protein profiles of two strains of M. hyopneumoniae were compared by two-dimensional gel electrophoresis and mass spectrometry. The results indicate that the major adhesin P97, the 50-kDa protein derived from P159 adhesin, and the 43-kDa cleavage product of P102 are expressed at much higher levels in the pathogenic strain 232. In contrast, the avirulent strain J switches its focus to metabolism and expresses more glyceraldehyde 3-phosphate dehydrogenase in gluconeogenesis and lactate dehydrogenase, pyruvate dehydrogenase, and phosphate acetyltransferase in the pyruvate metabolism pathway. We speculate that the avirulent strain may have developed better capabilities to cope with the rich environment during repeated inoculations. Simultaneously, the capability to infect host cells may become less important so that the adhesion-related protein genes are down-regulated.

Objective: To explore the molecular mechanisms of Shengqing Capsules in treating cholelithiasis., Methods: Sixty female guinea pigs were randomized into 3 groups: group I (fed with normal diet), group II (fed with low-protein diet) and group III (fed with low-protein diet and Shengqing Capsules). After six-week feeding, the gallstone formation and the expressions of bilirubin UDP-glucuronosyltransferase (B-UGT) mRNA and cholesterol 7alpha-hydroxylase (CYP7A1) mRNA were observed., Results: The proportions of stone-formed in groups I, II and III were 2/14, 9/12 and 4/14, respectively. There were significant differences among the three groups (P<0.05). The expressions of B-UGT and CYP7A1 mRNAs were higher in both group I and group III as compared with those in the group II (P<0.05)., Conclusion: Shengqing Capsules can reduce the rate of stone-formation, which may be due to its interference of metabolism of bilirubin and cholesterol and up-regulation of the expressions of B-UGT and CYP7A1 mRNAs.

Objective: To further probe the mechanisms of herbs for nourishing and smoothing the liver in reversing bile lithogenicity of guinea pig., Methods: Sixty guinea pigs were divided randomly into control group (fed with normal diet, n=20), model group (fed with lithogenic diet, n=20) and treatment group (fed with lithogenic diet plus herbal medicine, n=20). After four-week feeding, the animals were sacrificed and sampled, the rates of gallstone formation in each group were estimated, and the total bile acid (TBA), total bilirubin (TBIL), conjugated bilirubin (CB), unconjugated bilirubin (UCB), and calcium ion in the bile were determined, and the different bilirubins were analyzed by HPLC., Results: (1) The rate of gallstone formation was 5% in normal group, 81.25% in model group and 31.25% in treatment group (P<0.05). (2) The bile TBIL, CB, UCB and Ca(2+) were higher and the bile TBA was lower significantly in model group than that in the other two groups (P<0.05). (3) HPLC analysis revealed that MCB was higher and DCB was lower significantly in model group (P<0.01), and there were no significant differences of UCB and IPA among the three groups. (4) The percentages of MCB and UCB were much higher and the percentage of DCB was remarkably lower in model group (P<0.05)., Conclusion: Herbs for nourishing and smoothing the liver can significantly reduce the rate of gallstone formation and has effect of reversing lithogenicity of bile in guinea pigs fed with lithogenic diet.