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1.
Environ Res ; 203: 111894, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34418448

RESUMEN

The Tibetan Plateau (TP) has a variety of vegetation types that range from alpine tundra to tropic evergreen forest, which play an important role in the global carbon (C) cycle and is extremely vulnerable to climate change. The vegetation C uptake is crucial to the ecosystem C sequestration. Moreover, net reduction in vegetation C uptake (NRVCU) will strongly affect the C balance of terrestrial ecosystem. Until now, there is limited knowledge on the recovery process of vegetation net C uptake and the spatial-temporal patterns of NRVCU after the disturbance that caused by climate change and human activities. Here, we used the MODIS-derived net primary production to characterize the spatial-temporal patterns of NRVCU. We further explored the influence factors of the net reduction rate in vegetation C uptake (NRRVCU) and recovery processes of vegetation net C uptake across a unique gradient zone on the TP. Results showed that the total net reduction amount of vegetation C uptake gradually decreased from 2000 to 2015 on the TP (Slope = -0.002, P < 0.05). Specifically, an increasing gradient zone of multi-year average of net reduction rate in vegetation carbon uptake (MYANRRVCU) from east to west was observed. In addition, we found that the recovery of vegetation net C uptake after the disturbance caused by climate change and anthropogenic disturbance in the gradient zone were primarily dominated by precipitation and temperature. The findings revealed that the effects of climate change on MYANRRVCU and vegetation net C uptake recovery differed significantly across geographical space and vegetation types. Our results highlight that the biogeographic characteristics of the TP should be considered for combating future climate change.


Asunto(s)
Cambio Climático , Ecosistema , Efectos Antropogénicos , Carbono , Humanos , Temperatura , Tibet
2.
J Environ Qual ; 46(1): 64-71, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28177404

RESUMEN

Spatiotemporal patterns of forest carbon (C) sinks and accurate estimation of such patterns are crucial to sustainable forest management. We combined individual tree biomass equations and a Random Forest algorithm to assess the spatiotemporal changes in biomass C sequestration and to further quantify the relative contributions of forest areal expansion and growth to biomass C sinks in Sichuan Province, China, over the past 25 yr. Forest area and average biomass C density increased from 10.5 million ha and 45.7 Mg C ha in 1988 to 14.2 million ha and 52.3 Mg C ha in 2012. Average C density was generally larger in the north and west of Sichuan Province compared with other regions. The expanded forest area and enhanced C density have jointly led to a rise in total C storage by 54.9% over this period in Sichuan Province. It was estimated that the forest areal expansion has been a larger contributor to C sinks than forest growth in Sichuan Province (69 vs. 31%), especially in the regions of the northwestern high mountains and the hilly country of the Sichuan basin. However, the relative contributions of areal expansion exhibited different trends in five subregions and 15 forest species groups in this province. Our study suggests that it is necessary to develop a new forestry management mode to maintain the long-term health of forest ecosystems in Sichuan Province, which should attach more importance to improving forest quality and selecting tree species in different subregions while increasing forested area in the future.


Asunto(s)
Secuestro de Carbono , Ecosistema , Árboles , Biomasa , Carbono , China
3.
Nat Commun ; 15(1): 1085, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316787

RESUMEN

Limiting global warming to within 1.5 °C might require large-scale deployment of premature negative emission technologies with potentially adverse effects on the key sustainable development goals. Biochar has been proposed as an established technology for carbon sequestration with co-benefits in terms of soil quality and crop yield. However, the considerable uncertainties that exist in the potential, cost, and deployment strategies of biochar systems at national level prevent its deployment in China. Here, we conduct a spatially explicit analysis to investigate the negative emission potential, economics, and priority deployment sites of biochar derived from multiple feedstocks in China. Results show that biochar has negative emission potential of up to 0.92 billion tons of CO2 per year with an average net cost of US$90 per ton of CO2 in a sustainable manner, which could satisfy the negative emission demands in most mitigation scenarios compatible with China's target of carbon neutrality by 2060.


Asunto(s)
Dióxido de Carbono , Carbono , Carbón Orgánico , Carbono/análisis , Dióxido de Carbono/análisis , Objetivos , Suelo , China , Secuestro de Carbono
4.
Sci Total Environ ; 918: 170732, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38340857

RESUMEN

As a typical industrial and agricultural province, Shandong is one of China's most seriously air-polluted regions. One comprehensive ammonia emission inventory with a high spatial resolution (1 km × 1 km) for 136 county-level administrative divisions in Shandong from 2000 to 2020 is developed based on county-level activity data with the corrected and updated emission factors of seventy-seven subcategories. Annual ammonia emissions decrease from 1003.3 Gg in 2000 to 795.9 Gg in 2020, with an annual decrease rate of 1.2 %. Therein, the ammonia emissions associated with livestock and farmland ecosystems in 2020 account for 50.8 % and 32.9 % of the provincial total ammonia emission, respectively. Laying hen and wheat are the livestock and crop with the highest ammonia emissions, accounting for 23.3 % and 36.3 % of ammonia emissions from livestock and the application of synthetic fertilizers, respectively. Furthermore, waste treatment, humans and vehicles are the top three ammonia emission sources in urban areas, accounting for 5.0 %, 4.7 % and 1.3 % of total ammonia emissions, respectively. The spatial distribution of grids with high ammonia emissions is consistent with the distribution of intensive farms. Significant emission intensity areas mainly concentrate in western Shandong (e.g., Caoxian of Heze, Qihe of Dezhou, Yanggu of Liaocheng, Liangshan of Jining) due to the large area of arable land and the high levels of agricultural activity. Overall, prominent seasonal variability characteristics of ammonia emission are observed. Ammonia emissions tend to be high in summer and low in winter, and the August to January-emission ratio is 5.6. The high temperature and fertilization for maize are primarily responsible for Shandong's increase in ammonia emissions in summer. Finally, the validity of the estimates is further evaluated using uncertainty analysis and comparison with previous studies. This study can provide information to determine preferentially effective PM2.5 control strategies.

5.
Sci Total Environ ; 929: 172551, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38643870

RESUMEN

The rapid expansion of green areas in China has enhanced carbon sinks, but it also presents challenges regarding increased biogenic volatile organic compound (BVOC) emissions. This study examines the impact of greening trends on BVOC emissions in China from 1985 to 2001 and from 2001 to 2022, focusing on evaluating long-term trends in BVOC emissions within eight afforestation project areas during these two periods. Emission factors for 62 dominant tree species and provincial Plant Functional Types were updated. The BVOC emission inventories were developed for China at a spatial resolution of 27 km × 27 km using the Model of Emissions of Gases and Aerosols from Nature. The national BVOC emissions in 2018 were estimated at 54.24 Tg, with isoprene, monoterpenes, sesquiterpenes, and other BVOC contributing 26.94 Tg, 2.29 Tg, 0.44 Tg, and 24.57 Tg, respectively. Over the past 37 years, BVOC emissions experienced a slow growth rate of 1.7 % (0.79 Tg) during 1985-2001, followed by a significant increase of 12 % (6 Tg) from 2001 to 2022. BVOC emissions in the eight afforestation project areas increased by 2 % and 20 % during the two periods. From 2001 to 2022, at the regional scale, the Shelterbelt program for the middle reaches of the Yellow River area exhibited the largest rate of increase (43 %) in BVOC emissions. The Shelterbelt program for the upper and middle reaches of the Yangtze River made the most largest contribution (45 %) to the national increase in BVOC emissions. Afforestation projects have shifted towards planting more broadleaf trees than needleleaf trees from 2001 to 2022, and there also showed a change from herbaceous plants to broadleaf trees. These trends have led to higher average emission factors for vegetation, resulting in increased BVOC emissions. It underscores the importance of considering BVOC emissions when evaluating afforestation initiatives, emphasizing the need to balancing ecological benefits with potential atmospheric consequences.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Compuestos Orgánicos Volátiles , China , Compuestos Orgánicos Volátiles/análisis , Contaminantes Atmosféricos/análisis , Bosques , Árboles , Contaminación del Aire/estadística & datos numéricos , Agricultura Forestal
6.
J Mol Diagn ; 24(8): 878-892, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35718091

RESUMEN

Many diseases are related to multiple genetic alterations within a single gene. Probing for highly multiple (>10) variants in a single quantitative PCR tube is impossible because of a limited number of fluorescence channels and the limited ability to test one variant per channel, increasing the need for tubes. Herein, a novel color-mixing strategy was experimentally validated that uses fluorescence combinations as digital color codes to probe multiple variants simultaneously. The color-mixing strategy relies on a simple intratube assay that can probe for 15 variants as part of an intertube assay that can probe for an exponentially increased number of variants. This strategy is achieved by using multiplex double-stranded toehold probes modified with fluorophores and quenchers; the probes are designed to be quenched or remain luminous after binding to wild-type or variant templates. The color-mixing strategy was used to probe for 21 pathogenic variants in thalassemia and to distinguish between heterozygous and homozygous variants in six tubes, with a specificity of 99% and a sensitivity of 94%. To support tuberculosis diagnosis, the same strategy was applied to simultaneously probe in Mycobacterium tuberculosis for rifampicin-resistance mutations occurring within one 81-bp region and one 48-bp region in the rpoB gene, plus five isoniazid-resistance mutations in the inhA and katG genes.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Antituberculosos , Proteínas Bacterianas/genética , Humanos , Isoniazida , Pruebas de Sensibilidad Microbiana , Mutación , Mycobacterium tuberculosis/genética , Rifampin
7.
PeerJ ; 9: e12201, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34721962

RESUMEN

BACKGROUND: Climate change has altered global hydrological cycles mainly due to changes in temperature and precipitation, which may exacerbate the global and regional water shortage issues, especially in the countries along the Belt and Road (B&R). METHODS: In this paper, we assessed water supply, demand, and stress under three climate change scenarios in the major countries along the Belt and Road. We ensembled ten Global Climate Model (GCM) runoff data and downscaled it to a finer resolution of 0.1° × 0.1° by the random forest model. RESULTS: Our results showed that the GCM runoff was highly correlated with the FAO renewable water resources and thus could be used to estimate water supply. Climate change would increase water supply by 4.85%, 5.18%, 8.16% and water demand by 1.45%, 1.68%, 2.36% under RCP 2.6, 4.5, and 8.5 scenarios by 2050s, respectively. As a result, climate change will, in general, have little impact on water stress in the B&R countries as a whole. However, climate change will make future water resources more unevenly distributed among the B&R countries and regions, exacerbating water stress in some countries, especially in Central Asia and West Asia. Our results are informative for water resource managers and policymakers in the B&R countries to make sustainable water management strategies under future climate change.

8.
J Biochem Mol Toxicol ; 24(5): 293-302, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20979155

RESUMEN

Heat shock protein 70 (HSP70) protect cell from oxidative stress by preventing the irreversible loss of vital proteins and facilitating their subsequent regeneration. Silver carp (Hypophthalmichthys molitrix), grass carp (Ctenopharyngodon idellus), and Nile tilapia (Oreochromis nilotica) are three warm freshwater fishes with differential tolerance to microcystin-LR (MC-LR). Full-length cDNAs encoding the HSP70 were cloned from the livers of the three fishes. The HSP70 cDNAs of silver carp, grass carp, and Nile tilapia were 2356, 2348, and 2242 bp in length and contained an open-reading frame of 1950 bp (encoding a polypeptide of 649 amino acids), 1950 bp (649 amino acids), and 1917 bp (638 amino acids), respectively. Like mammalian HSP70, the HSP70 of the three fish was also composed of an ATPase domain from residues 1 to 383 (44 kDa), substrate peptide binding domain from residues 384 to 544 (18 kDa), and a C-terminus domain from residues 545 to 649 (10 kDa). The relatively high conservation of HSP70 sequences among different vertebrates is consistent with their important role in fundamental cellular processes. Using beta-actin as an external control, RT-PCR within the exponential phase was conducted to determine the constitutive and inducible expression level of HSP70 gene among the three fishes (6-12 g) intraperitoneally injected with MC-LR (50 µg kg(-1) body weight). Both constitutive and inducible liver mRNA levels of the fish HSP70 genes showed positive relationships with their tolerance to MC-LR: highest in Nile tilapia, followed by silver carp, and lowest in grass carp. The differential expression pattern of liver HSP70 genes in the three fish indicated a potential role of HSP70 in the detoxification process of MC-LR.


Asunto(s)
Tolerancia a Medicamentos/genética , Peces/genética , Proteínas HSP70 de Choque Térmico/genética , Hígado/metabolismo , Toxinas Marinas/toxicidad , Actinas/genética , Actinas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Carpas/genética , Carpas/metabolismo , Cíclidos/genética , Cíclidos/metabolismo , Clonación Molecular , Secuencia Conservada , ADN Complementario/genética , ADN Complementario/metabolismo , Peces/metabolismo , Agua Dulce , Proteínas HSP70 de Choque Térmico/biosíntesis , Proteínas HSP70 de Choque Térmico/metabolismo , Microcistinas/toxicidad , Alineación de Secuencia
9.
Ying Yong Sheng Tai Xue Bao ; 31(7): 2332-2340, 2020 Jul.
Artículo en Zh | MEDLINE | ID: mdl-32715699

RESUMEN

It is the goal of protected area management to make full use of limited resources to better protect biodiversity. Currently, the main tasks of developing national park system in China are to combine conservation features, optimize the spatial network of protected areas, and identify the prio-rity conservation areas of national parks effectively. In this study, we assessed the spatial distribution of key ecosystem services (carbon sequestration, oxygen release, hydrological regulation, water resources, and soil retention) using ecological model, and simulated the distribution of suitable habitats for 37 endangered species by MaxEnt in Lishui City, Zhejiang Province. The irreplaceability index of each planning unit in Lishui was calculated on the 0.4 km×0.4 km grid using the systema-tic conservation planning model (MARXAN), setting key ecosystem services and endangered species as the conservation objects. Combined with the local management needs, the priority protection areas of national parks were identified comprehensively. The results showed that during 2005 to 2015, the annual carbon storage, oxygen release, hydrological regulation, water resource, and soil retention in the study area was 0.05 kg C·m-2·a-1, 0.13 kg O2·m-2·a-1, 83.25×108 m3·a-1, 803 mm·a-1, and 95.53 t·hm-2·a-1, respectively. The irreplaceability index of different land use types was significantly different. The irreplaceability index of forest, river and reservoir, garden, cultivated land, residential land was 50-100, 60-100, 30-50, 15-35, 0-25, respectively. The priority conservation areas accounted for 11.8% of the study area. This study put forward a systematic conservation planning idea combining biodiversity and ecosystem services, which could provide a useful framework and technical support for optimizing the network layout of protected areas and priority conservation areas of national parks, and help to enhance the overall effectiveness of the establishment of the protected areas system with national parks as its main type in China.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Biodiversidad , China , Ciudades , Parques Recreativos
10.
Ecol Evol ; 9(1): 427-436, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30680125

RESUMEN

Climate change-induced species range shift may pose severe challenges to species conservation. The Qinghai-Tibet Plateau is the highest and biggest plateau, and also one of the most sensitive areas to global warming in the world, which provides important shelters for a unique assemblage of species. Here, ecological niche-based model was employed to project the potential distributions of 59 key rare and endangered species under three climate change scenarios (RCP2.6, RCP4.5 and RCP8.5) in Qinghai Province. I assessed the potential impacts of climate change on these key species (habitats, species richness and turnover) and effectiveness of nature reserves (NRs) in protecting these species. The results revealed that that climate change would shrink the geographic ranges of about a third studied species and expand the habitats for two thirds of these species, which would thus alter the conservation value of some local areas and conservation effectiveness of some NRs in Qinghai Province. Some regions require special attention as they are expected to experience significant changes in species turnover, species richness or newly colonized species in the future, including Haidong, Haibei and Haixi junctions, the southwestern Yushu, Qinghai Nuomuhong Provincial NR, Qinghai Qaidam and Haloxylon Forest NR. The Haidong and the eastern part of Haibei, are projected to have high species richness and conservation value in both current and future, but they are currently not protected, and thus require extra protection in the future. The results could provide the first basis on the high latitude region to formulate biodiversity conservation strategies on climate change adaptation.

11.
J Environ Qual ; 36(1): 291-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17215238

RESUMEN

The plateau lakes of Yunnan are important both ecologically and economically in China. Nevertheless, the human impact on water quality in these lakes has become increasingly highlighted. The water quality of 10 plateau lakes was monitored regularly over the period of 2000 through 2004 for 24 parameters. Multivariate statistical techniques, including cluster analysis (CA), factor analysis (FA), and principal component analysis (PCA), were employed to better interpret information about the water quality and its pollution sources. No obvious data reduction from CA/FA was found because three principal components (PCs) needed 14 variables to explain 85.01% of the total variance. However, three latent factors accounted for pollution mainly from the following sources: agricultural activities, residential activities and anthropogenic-toxic pollution from industrial effluents, or other special activities. Box-whiskers plots were employed to visually interpret the spatiotemporal variations of water quality variables, which were highly correlated with three PCs. Three types of water quality (i.e., low-, medium-, and high-polluted lakes) were determined through CA based on the similarity of water quality variables. Our results may provide helpful information for the authorities to effectively manage the water quality and make sound policies.


Asunto(s)
Contaminantes del Agua , Agua/normas , China
12.
Sci Rep ; 7(1): 12705, 2017 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-28983118

RESUMEN

Conservationists strive for practical, cost-effective management solutions to forest-based species conservation and climate change mitigation. However, this is compromised by insufficient information about the effectiveness of protected areas in increasing carbon storage, and the co-benefits of species and carbon conservation remain poorly understood. Here, we present the first rigorous quantitative assessment of the roles of giant panda nature reserves (NRs) in carbon sequestration, and explore the co-benefits of habitat conservation and climate change mitigation. Results show that more than 90% of the studied panda NRs are effective in increasing carbon storage, with the mean biomass carbon density of the whole NRs exhibiting a 4.2% higher growth rate compared with lands not declared as NRs over the period 1988-2012, while this effectiveness in carbon storage masks important patterns of spatial heterogeneity across the giant panda habitats. Moreover, the significant associations have been identified between biomass carbon density and panda's habitat suitability in ~85% NRs and at the NR level. These findings suggest that the planning for carbon and species conservation co-benefits would enhance the greatest return on limited conservation investments, which is a critical need for the giant panda after its conservation status has been downgraded from "endangered" to "vulnerable".


Asunto(s)
Carbono/metabolismo , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Ursidae/fisiología , Animales , Secuestro de Carbono , Cambio Climático , Ecosistema , Bosques , Ursidae/metabolismo
13.
Artículo en Inglés | MEDLINE | ID: mdl-16737855

RESUMEN

After Sepharose 4B polymer beads were activated by using epichlorohydrin, hemin was binded with them to prepare an immobilized hemin affinity chromatography column. The coupling rate of this column was very high, more than 0.25mg hemin could be fixed by 1g of wet Sepharose 4B beads. The column equilibrated with deionized water and eluated with pH 3.0 NaAc-HAc buffer was applied to capture the proteins in human serum, earthworm body and Bacillus subtilis cells. Three polypeptides in human serum were captured, one of which was verified as serum albumin after comparison to the control. At least one polypeptide in earthworm body, two in Bacillus subtilis cells displayed the powerful binding specificity to hemin. Our experiments demonstrated that the immobilized hemin affinity chromatography was available as a probe for some proteins having potentiality to bind with heme.


Asunto(s)
Cromatografía de Afinidad/métodos , Hemo/metabolismo , Hemina/química , Sondas Moleculares , Proteínas/metabolismo , Animales , Electroforesis en Gel de Poliacrilamida , Humanos , Unión Proteica
14.
PLoS One ; 11(5): e0156586, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27243772

RESUMEN

Water is a limiting factor for plant growth and vegetation dynamics in alpine sandy land of the Tibetan Plateau, especially with the increasing frequency of extreme precipitation events and drought caused by climate change. Therefore, a relatively stable water source from either deeper soil profiles or ground water is necessary for plant growth. Understanding the water use strategy of dominant species in the alpine sandy land ecosystem is important for vegetative rehabilitation and ecological restoration. The stable isotope methodology of δD, δ18O, and δ13C was used to determine main water source and long-term water use efficiency of Salix psammophila and S. cheilophila, two dominant shrubs on interdune of alpine sandy land in northeastern Tibetan Plateau. The root systems of two Salix shrubs were investigated to determine their distribution pattern. The results showed that S. psammophila and S. cheilophila absorbed soil water at different soil depths or ground water in different seasons, depending on water availability and water use strategy. Salix psammophila used ground water during the growing season and relied on shallow soil water recharged by rain in summer. Salix cheilophila used ground water in spring and summer, but relied on shallow soil water recharged by rain in spring and deep soil water recharged by ground water in fall. The two shrubs had dimorphic root systems, which is coincident with their water use strategy. Higher biomass of fine roots in S. psammophila and longer fine roots in S. cheilophila facilitated to absorb water in deeper soil layers. The long-term water use efficiency of two Salix shrubs increased during the dry season in spring. The long-term water use efficiency was higher in S. psammophila than in S. cheilophila, as the former species is better adapted to semiarid climate of alpine sandy land.


Asunto(s)
Hojas de la Planta/fisiología , Raíces de Plantas/fisiología , Salix/fisiología , Agua , Cambio Climático , Clima Desértico , Ecosistema , Transpiración de Plantas , Salix/crecimiento & desarrollo , Estaciones del Año , Tibet
15.
Bioresour Technol ; 198: 77-86, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26364231

RESUMEN

Sodium sulfide (SS) was added to the non-detoxified wheat straw hydrolysate for ABE fermentation by Clostridium acetobutylicum CICC8012. Biochemical measurements demonstrated that supplementation with SS promoted earlier and enhanced conversion of acid to ABE and led to a 27.48% improvement in sugar consumption, a 20.48% improvement in the sugar-based ABE yield, a 47.63% improvement in the butanol titer, and a 53.50% improvement in the ABE concentration. The response of C. acetobutylicum CICC8012 at the mRNA level was examined by a transcriptional analysis performed with RNA sequencing. The expression of genes involved in the membrane transport of carbohydrates, glycolysis, and ABE formation increased following SS-supplemented fermentation, whereas the expression of genes encoding enzymes involved in acid formation decreased, which indicates that supplemental SS affected the central fermentative pathway, down-regulated the metabolic flux toward the acid formation branches, and up-regulated the metabolic flux toward the ABE formation branches.


Asunto(s)
1-Butanol/metabolismo , Clostridium acetobutylicum/metabolismo , Tolerancia a Medicamentos , Fermentación , Análisis de Secuencia de ARN , Triticum/metabolismo , Secuencia de Bases , Carbohidratos , Hexosas/metabolismo , Hidrólisis , Sulfuros
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(1): 95-7, 2004 Jan.
Artículo en Zh | MEDLINE | ID: mdl-15768987

RESUMEN

The visible spectra of hemin, hemoglobin, cytochrome C, peroxidase and so on were compared and analyzed based on the experiments. The fifth and sixth coordinate bond of heme iron in biomacromolecule may affect their visible spectra in peak form and position. The sixth coordinate bond of ferrous heme iron that is in low-spin displays two peaks, and in high-spin, ferrous heme without the sixth coordinate bond of iron gives only one peak. That is in favor of our understanding of the character, function and stability of heme-containing biomacromolecule. The spectral character of iron coordinate bonds is due to that these coordinate bonds change the iron position related to porphyrin plane and its spin state.


Asunto(s)
Hemina/química , Oxígeno/química , Porfirinas/química , Espectrometría Raman/métodos , Catálisis , Citocromos c'/química , Espectroscopía de Resonancia por Spin del Electrón , Hemo/química , Hierro/química , Modelos Químicos , Mutagénesis Sitio-Dirigida , Porfirinas/genética , Unión Proteica , Conformación Proteica , Especificidad por Sustrato
17.
Artículo en Inglés | MEDLINE | ID: mdl-23644499

RESUMEN

The histones including H2a, H2b, H3 and H4 purified from pig liver tissue were immobilized onto Sepharose 4B to create a histone-Sepharose column. During chromatography of cow milk casein by histone-Sepharose column, two isoforms of prion protein (PrP(c)) with 34 and 30kDa molecular mass corresponding to diglycosylated and monoglycosylated PrP(c) respectively were found to be captured by histone ligands. To further verify the interaction between histones and PrP(c), the PrP(c)-Sepharose column was prepared and used to separate the histones. Two chromatography processes and SDS-PAGE demonstrated that only H3 in the histones was found to interact with PrP(c). This study suggested H3 could be the target molecule of PrP(C) in nuclei, which might be useful for understanding the prion disease.


Asunto(s)
Cromatografía de Afinidad/métodos , Histonas/química , Priones/química , Animales , Bovinos , Electroforesis en Gel de Poliacrilamida , Porcinos
18.
Se Pu ; 30(8): 851-5, 2012 Aug.
Artículo en Zh | MEDLINE | ID: mdl-23256392

RESUMEN

The isoelectric points of immunoglobulin (Ig) and serum albumin (SA) in animal serum are about 7.8 and 4.8, respectively. Based on their larger difference of isoelectric points, Q Sepharose-XL strong anion exchange chromatography coupled with molecular exclusion chromatography was used to purify Ig and SA simultaneously from the high immune rabbit serum. After the Q Sepharose-XL strong anion exchange column was equilibrated with 0.02 mol/L Tris-HCl buffer of pH 8.0, a 10-fold dilution sample of rabbit serum was loaded onto the column and the pH gradient elution was performed. With the low flow rate of elution of 0.3 mL/min, the high-purity Ig was obtained when the elution pH was at 6.0. Continuously eluted at pH 4.0 with the same flow rate of elution, the SA was obtained and its purity was greater than 95% after molecular exclusion chromatography through Sephadex G-75. The purified Ig and SA were demonstrated to maintain normal activities by activity analysis. The results of protein content showed that the purification recoveries of Ig and SA were over 95% and 90%, respectively. The method has the advantages of simple operation and rapidity, and the Ig and SA purified simultaneously from the animal serum could maintain normal activities.


Asunto(s)
Cromatografía en Gel/métodos , Cromatografía por Intercambio Iónico/métodos , Inmunoglobulinas/aislamiento & purificación , Albúmina Sérica/aislamiento & purificación , Suero/química , Animales , Resinas de Intercambio Aniónico/química , Aniones/química , Peso Molecular , Conejos
19.
Integr Zool ; 5(2): 154-163, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21392333

RESUMEN

Climate change will cause range shifts of many species in the future. Galliformes might be particularly vulnerable to climate change, as they have low dispersal ability. Little is known about their possible responses to the future climate. We used a generalized additive model to predict the current and future ranges of all 63 Galliformes in China, based on a comprehensive species occurrence database and a combination of climate variables. Other environmental variables (e.g. elevation and human footprint index) were also considered, as well as the latitude and longitude of the occurrences. Principal component analysis was conducted to illustrate the association between environmental variables and Galliformes distributions. Using the Special Report on Emissions Scenarios (SRES) A2 climate change scenario for 2071-2100, we projected that 29 species would have range shifts over 50%, including 13 endemic species. Galliformes at higher elevation face greater range shifts. Northward shifts are greater than those in other directions. We suggest conservationists pay special attention to the 29 Galliformes that face extensive range shifts, especially the endemic species among them.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales/métodos , Demografía , Galliformes/fisiología , Modelos Biológicos , Altitud , Animales , China , Geografía , Dinámica Poblacional , Especificidad de la Especie
20.
Se Pu ; 25(3): 332-6, 2007 May.
Artículo en Zh | MEDLINE | ID: mdl-17679423

RESUMEN

The S-type lectins in annelida are different in molecular structure and biochemical properties from that of common galectin and are valuable in anticancer study. Based on their specificity, Sepharose CL-6B affinity chromatography was adopted in this study to separate the S-type lectin in annelida from earthworms, in which EDTA-MEPBS (2 mmol/L EDTA, 4 mmol/L beta-mercaptoethanol, 150 mmol/L NaCl, 20 mmol/L phosphate, pH 7.2) was used as an equilibrium solution and aqueous ammonia solution (150 mmol/L, pH 10.5) as an eluent. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed that the relative molecular mass of the obtained protein in this purification procedure was about 32 000 and it could be further separated into fractions with relative molecular mass about 15 000. Hemagglutination experiment and fluorescence analysis demonstrated that this protein possessed the characteristics of agglutinin and its complex with lactose. This indicated that the target protein was one of the S-type lectins in annelida. This study may offer a novel and rapid method for purifying the S-type lectins in annelida in large scale.


Asunto(s)
Cromatografía de Afinidad/métodos , Galectinas/aislamiento & purificación , Oligoquetos/química , Sefarosa/análogos & derivados , Animales , Electroforesis en Gel de Poliacrilamida , Sefarosa/química
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