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151.
The melanocortin-4 receptor (MC4R), a G protein-coupled seven-transmembrane receptor, which is expressed in the brain, plays an important role in the control of mammalian energy homeostasis. A missense mutation (Asp298Asn) was identified in the porcine MC4R gene, which is associated with growth and food intake traits. The Asn298 mutation occurs within a highly conserved motif, NPLIY, of all members of G protein-coupled receptors; whereas, Asp298 is conserved in all five melanocortin receptor subtypes. Functional analysis of the porcine MC4R variant was performed with an in vitro gene expression system in 293 cells. Ligand binding (NDP-alphaMSH) did not differ between Asp298 and Asn298 MC4R proteins. However, the Asn298 MC4R variant was unable to stimulate cAMP production in response to NDP-alphaMSH stimulation; whereas, the Asp298 variant could stimulate cAMP accumulation. These results demonstrate that the Asp298 is required for normal MC4R signaling to the adenylyl cyclase. Sequencing of the MC4R gene of seven diverse genera within the Suiformes that include Hippopotamidae (hippos), Tayassuidae (peccaries) and Suidae (pigs), revealed 62 nucleotide variations in MC4R. Phylogenetic relationships of MC4R variations are consistent with those previously described from morphological and physiological data among the subfamilies of the Suiformes. These findings revealed that a single missense mutation (Asp298Asn) of aspartic acid (Asp) to asparagine (Asn) in MC4R gene decreased cAMP content and MC4R signaling, but with no difference in the ligand binding was associated with growth and feed intake traits in domestic pigs. 相似文献
152.
Li-Chan EC Hunag SL Jao CL Ho KP Hsu KC 《Journal of agricultural and food chemistry》2012,60(4):973-978
The dipeptidyl-peptidase IV (DPP-IV)-inhibitory activity of peptides derived from Atlantic salmon skin gelatin hydrolyzed by alcalase (ALA), bromelain (BRO), and Flavourzyme (FLA) was determined. The FLA hydrolysate with the enzyme/substrate ratio of 6% showed the greatest DPP-IV-inhibitory activity. The hydrolysate was fractionated by ultrafiltration with 1 and 2.5 kDa cutoff membranes, and the <1 kDa fraction had the highest DPP-IV-inhibitory activity with an IC(50) value of 1.35 mg/mL. The F-1 fraction further isolated by HPLC showed the IC(50) value against DPP-IV of 57.3 μg/mL, and the peptide sequences were identified as Gly-Pro-Ala-Glu (372.4 Da) and Gly-Pro-Gly-Ala (300.4 Da). The synthetic peptides showed dose-dependent inhibition effects on DPP-IV with IC(50) values of 49.6 and 41.9 μM, respectively. The results suggest that the peptides derived from Atlantic salmon skin gelatin would be beneficial ingredients for functional foods or pharmaceuticals against type 2 diabetes. 相似文献
153.
Rice starch suspensions of 10% dry matter (DM) were treated by heat (0.1 MPa at 20–85 °C) or pressure/heat combinations (100–600 MPa at 20, 40 and 50 °C) for 15 min to investigate their gelatinization and rheological characteristics. The maximum swelling index of about 12 g water per gram of DM was obtained by thermal treatment at 85 °C, meanwhile, that of 7.0 g was observed by 600-MPa pressurization at 50 °C. The higher temperatures or pressures resulted in the higher degrees of gelatinization. Furthermore, treatments of 0.1 MPa at 85 °C, 500 MPa at 50 °C and 600 MPa at various temperatures caused complete gelatinization of rice starch. The consistency index (K) and storage modulus (G′) dramatically increased from 70 °C or 400 MPa. The G′ values were higher in pressure-treated samples than those in thermal-treated samples. Therefore, an application of pressure/heat combinations as a processing method to improve the quality of rice starch products would be possible. 相似文献
154.
Chih-Hung Lin Shih-Tien Hsu Kuo-Ching Tzeng Jaw-Fen Wang 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(1):75-85
Bacterial wilt caused by race 1 strains of Ralstonia solanacearum is endemic on tomato produced in diverse agro-ecosystems in Taiwan. Using a new BIO-PCR protocol developed in this study,
R. solanacearum was detected in soil, weed, and water samples collected from eight fields with different disease histories and cropping systems
located in major tomato production areas. The sensitivity of the BIO-PCR was 1.9 CFU ml−1 and 17 CFU g−1 of soil for pure suspension and infested soil, respectively. The positive detection frequency of the BIO-PCR method was 66.6,
39.6, 23.1, and 31.8% for all tested samples of soil, weed rhizosphere soil, weed root, and water, respectively, and was higher
than plating on MSM-1 medium. Detection of R. solanacearum from field soil indicated that spatial distribution of the pathogen in the field was not even regardless of the presence
or absence of the disease and the different agro-ecosystems where the sampled fields were located, and the degree of unevenness
was higher when tomato was absent from the field. Weed rhizosphere soils could be good sampling targets to monitor the pathogen
in the field, because a higher positive detection proportion and population of R. solanacearum were found in the rhizosphere rather than the root of the collected weed samples. Symptomless weeds and contaminated irrigation,
standing, or drainage waters were found to be important for the over-season survival and dissemination of R. solanacearum. 相似文献
155.
156.
In Australian Aboriginal thinking, the idea of ‘Country’ comprises complex ideas about relationships and connection. It simultaneously encompasses territorial affiliation, a social identification and cosmological orientation. It draws attention to what might be glossed as people‐to‐environment, people‐to‐people and people‐to‐cosmos relations. These relations influence disaster responses, but are rarely mobilised explicitly in shaping formal recovery and reconstruction efforts. Colonial disruption of connections to Country imposed new practices and presences into contemporary Indigenous geographies and is often reinforced in disaster settings. This paper considers more recent disruptions arising from post‐disaster recovery in Taiwan, arguing that the idea of Country offers a powerful way of framing cultural and social dimensions of post‐disaster relief and recovery for government agencies, non‐government organisations and research alike. 相似文献
157.
Randomly oriented strand boards with both uniform and conventional vertical density profiles (VDP) were manufactured, and their properties were evaluated and compared. The bending modulus of elasticity (MOE) of conventional strand boards was predicted using the laminated beam theory and the MOE-density regression equation from the uniform strand boards. The results showed that the predicted MOE of conventional strand boards was close to the measured MOE with a difference of less than 10%. The internal bond strength values of uniform strand boards were found to be higher than conventional strand boards while no significant difference was found in water-related properties. Compared with uniform strand boards, MOE values of conventional strand boards were improved only at higher density level. About 10% of improvement in MOE can be obtained for the strand boards investigated by manipulating the VDP. Steeper VDPs were predicted to be required for thinner boards than for thick boards in order to achieve the same improvement in MOE. 相似文献
158.
159.
Perceptions and Practices of Mass Bat Exposure Events in the Setting of Rabies Among U.S. Public Health Agencies
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C. H. Hsu C. M. Brown J. M. Murphy M. G. Haskell C. Williams K. Feldman K. Mitchell J. D. Blanton B. W. Petersen R. M. Wallace 《Zoonoses and public health》2017,64(2):127-136
Current guidelines in the setting of exposures to potentially rabid bats established by the Advisory Committee on Immunization Practices (ACIP) address post‐exposure prophylaxis (PEP) administration in situations where a person may not be aware that a bite or direct contact has occurred and the bat is not available for diagnostic testing. These include instances when a bat is discovered in a room where a person awakens from sleep, is a child without an adult witness, has a mental disability or is intoxicated. The current ACIP guidelines, however, do not address PEP in the setting of multiple persons exposed to a bat or a bat colony, otherwise known as mass bat exposure (MBE) events. Due to a dearth of recommendations for response to these events, the reported reactions by public health agencies have varied widely. To address this perceived limitation, a survey of 45 state public health agencies was conducted to characterize prior experiences with MBE and practices to mitigate the public health risks. In general, most states (69% of the respondents) felt current ACIP guidelines were unclear in MBE scenarios. Thirty‐three of the 45 states reported prior experience with MBE, receiving an average of 16.9 MBE calls per year and an investment of 106.7 person‐hours annually on MBE investigations. PEP criteria, investigation methods and the experts recruited in MBE investigations varied between states. These dissimilarities could reflect differences in experience, scenario and resources. The lack of consistency in state responses to potential mass exposures to a highly fatal disease along with the large contingent of states dissatisfied with current ACIP guidance warrants the development of national guidelines in MBE settings. 相似文献
160.
Identification of natural variants affecting chlorophyll content dynamics during rice seedling development
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Po‐Chun Lin Yu‐Chang Tsai Sheng‐Kai Hsu Jen‐Hsiang Ou Chen‐Tuo Liao Chih‐Wei Tung 《Plant Breeding》2018,137(3):355-363
Seedling vigour is an important characteristic in relation to crop growth and yield. Traits such as photosynthetic capacity and chlorophyll content contribute significantly to seedling establishment at the early growth stage in various crop species, including rice. A diverse panel of 227 rice varieties from several countries was evaluated to determine chlorophyll contents at multiple time points during the seedling stage using a soil–plant analysis development (SPAD) meter, a non‐destructive portable device. Using new statistical approaches, several chromosomal regions associated with variations in chlorophyll content in the third leaf at 13, 16 and 19 days after imbibition were detected. A single nucleotide polymorphism (SNP) cluster on the end of chromosome 11 was significantly associated with the onset of leaf senescence. This region was enriched with genes related to cell death and the stress response. We have identified rice germplasm showing delayed‐senescence phenotypes, these could be suitable donors and genetic resources for breeding, and the use of significant SNP markers associated with these traits could enhance the efficiency of their selection in breeding programmes. 相似文献