Search

[ Objective ] This study aims to explore the protective mechanism of exogenous silicon on water metabolism and photosynthesis of Cucurbita pepo L. seedlings under salt stress , and to provide theoretical reference for salt resistance of C . pepo L.. [ Methods ] Using “ Hanlu 7042 ” C . pepo L. variety as the test material and hydroponic experiment , four treatments were set : Control , silicon treatment ( 0.3 mmol / L Na 2 SiO 3 · 9H 2 O ), salt stress ( 150 mmol / L NaCl ), salt stress+silicon treatment ( 0.3 mmol / L Na 2 SiO 3 · 9H 2 O+150 mmol / L NaCl ) . After 10 days of treatment , root morphology and activity , leaf water con- tent and water potential , photosynthetic parameters , chlorophyll content , chlorophyll fluorescence param- eters , and expression of aquaporin genes were determined. [ Results ] Salt stress inhibited the growth of C . pepo L. seedling roots , and decreased root activity , leaf water content , and leaf water potential and tran- spiration. Salt stress also affected the photosynthetic system , net photosynthetic rate , stomatal conduct- ance , chlorophyll content , and PSⅡ photochemical efficiency. Exogenous silicon improved the root mor- phology and activity of C . pepo L. seedlings under salt stress , also improved plant water status , and leaf water content , leaf water potential , and transpiration by promoting the expression of genes PIP1 ; 2 , PIP1 ; 3 , PIP1 ; 5 , PIP1 ; 7 , PIP2 ; 1 , PIP2 ; 4 , PIP2 ; 6 , and PIP2 ; 8 , PIP2 ; 9 and PIP2 ; 12 . The exogenous silicon also increased the stomatal conductance , chlorophyll content , net photosynthetic rate , PSⅡ maximum photochemical efficiency , PSⅡ actual photochemical efficiency , and photochemical quenching coefficient , decreased intercellular carbon dioxide concentration and non-photochemical quench- ing coefficient , enhanced the photosynthesis of seedlings under salt stress. [ Conclusion ] 0.3 mmol / L sili- con could improve the water metabolism and photosynthesis of C . pepo L. seedlings under salt stress , and thus enhance the ability of C . pepo L. seedlings to resist salt stress.

Spacecraft missions are characterized by complex missions, high risks, high costs, high reliability, and long periods. In order to meet the needs of more complex spacecraft mission development in the future, model-based systems engineering (MBSE) methods is introduced in the spacecraft design and development. A model-based spacecraft development process and six types of model systems that meet the needs of the spacecraft development process are proposed, which are composed of demand model, function model, process model, architecture model, product model, and verification model. Taking the lunar water resource exploration as a hypothetical task, the MBSE modeling process and its model are presented, which fully embodies the advantages of the MBSE method in spacecraft design and simulation verification. [ABSTRACT FROM AUTHOR]

Changshaling Structural Belt is an important oil and gas exploration area in Jiudong Basin, and abnormal high pressure is universal in the zone. The paper proposes a new three-dimensional (3D)pore pressure calculation method based on single point hypothesis, which can use 3D interval velocity data to estimate 3D pore pressure. The novel method was applied to the 3D pore pressure calculation and analysis of Changshaling Structural Belt. Firstly, the pore pressure profile and model parameters of several key exploratory wells were established. Secondly, the 3D interval velocity data of the structural belt was obtained by seismic inversion. Further, the computer program was developed, and it was used to calculate the 3D pore pressure of Changshaling Structural Belt. Finally, with the 3D pressure results of Changshaling Structural Belt, the pore pressure distribution of this zone was systematically analyzed, with positive results. [ABSTRACT FROM AUTHOR]

Objective: To report on a novel KIR3DL3 allele identified in a southern Han Chinese individual., Methods: Peripheral blood sample was collected from a voluntary blood donor with inconclusive result by KIR3DL3 sequence-based typing (SBT). Total mRNA was extracted and subjected to reverse transcription to obtain KIR3DL3 cDNA, which was then amplified by PCR with a pair of KIR3DL3-specific primers. The product was subjected to cDNA cloning and sequencing., Results: cDNA cloning and sequencing have identified a wide-type KIR3DL3*00802 allele and a novel KIR3DL3*064 allele. The latter differed from KIR3DL3*00601 by a missense variant at codon 374[c.1184 C>T (p.Thr374Ile)] in exon 9. The novel KIR3DL3 allele has been officially assigned by the KIR subcommittee of World Health Organization Nomenclature Committee for factors of HLA system., Conclusion: cDNA cloning and sequencing may be used to distinguish inconclusive results in KIR3DL3 SBT in order to identify novel KIR alleles.

Objective: To study the polymorphisms of the KIR2DL4 gene in a southern Han Chinese population., Methods: Genomic DNA isolated from 306 unrelated individuals was amplified by using KIR2DL4-specific PCR primers. The PCR products were genotyped for the entire coding sequence by sequencing-based typing (SBT). Assignment of allelic profile was accomplished with an Assign 3.5 software. For samples with inconclusive SBT results, the RT-PCR products covering the entire coding sequence of the KIR2DL4 gene were subjected to cloning and haplotype sequencing., Results: Among the 306 individuals, 11 alleles were detected, of which 5 novel alleles were officially named by the KIR subcommittee of the World Health Organization Nomenclature Committee for factors of HLA system. The observed frequencies for the 11 alleles were KIR2DL4 *00102 (75.5%), *00103 (8.2%), *00501 (34.0%), *00503 (0.7%), *00504 (0.7%), *00602 (14.4%), *00801 (11.4%), *011 (22.2%), *032 (0.3%), *033 (0.3%) and *034 (0.3%). The ratio of 10A type alleles including 2DL4*00102, *00103, *00501, *00503, *00504, *00602, *032, *033, *034 and 9A type alleles including 2DL4*00801, *011 were 97.0% and 33.0%, respectively, with a ratio of 2.9:1., Conclusion: The allelic diversity of the KIR2DL4 gene in southern Han Chinese has been elucidated, which may provide valuable data for research on transplantation, reproductive immunity, KIR-associated disease and evolution.

Objective: To study genetic polymorphisms of the KIR2DS4 gene among ethnic Hans from southern China., Methods: Genomic DNA was isolated from 306 unrelated individuals and amplified with KIR2DS4-specific PCR primers. KIR2DS4-positive samples were genotyped for the entire coding sequence by sequencing-based typing (SBT). Assignment of allelic genotypes was accomplished by using Assign 3.5 software. For samples with inconclusive SBT results, RT-PCR products covering the entire coding sequence of the KIR2DS4 gene were subjected to cloning and haplotype sequencing., Results: Among all tested samples, 297 were demonstrated to have carried the KIR2DS4 framework gene. For KIR2DS4-positive samples subjected to SBT for the entire coding sequences, no background was observed with the obtained sequences. Three of the seven identified alleles were of novel types, which were officially named by the KIR subcommittee of the World Health Organization Nomenclature Committee for Factors of HLA System. The observed frequencies for the 7 alleles were KIR2DS4*00101 (78.8%), *003 (10.5%), *004 (16.0%), *010 (23.2%), *017 (0.3%), *00105 (0.3%) and *018 (0.7%), respectively. Allele KIR2DS4*007 was not found. The overall frequency for normal cell-surface expression KIR2DS4 alleles including 2DS4*00101, *017 and *00105 was 79.4%, and that for non cell-surface expression alleles including 2DS4*003, *004, *010 and *018 was 50.4%. The ratio between the two was 1.6:1., Conclusion: The present study has elucidated the allelic diversity of KIR2DS4 among ethnic Hans from southern China, which may provide valuable data for transplantation as well as studies on KIR-associated disease and evolution.

Objective: To categorize ambiguous allelic combinations encountered in genotyping of functional KIR genes by sequencing-based typing of the entire coding sequence and develop an efficient approach to identify such ambiguities., Methods: Fourteen KIR functional framework genes from 306 ethnic Chinese individuals were genotyped for the entire encoding sequence. The number of ambiguities was directly counted. Based on the differences within each ambiguous allelic combination, group-specific PCR primers and sequencing primers for amplifying the target allelic sequence were designed. The PCR products were then subjected to sequencing in order to identify the ambiguities., Results: The 14 functional KIR genes were subjected to sequencing-based typing (SBT) for the entire encoding sequence. Six ambiguous allelic combinations were identified. The most common ambiguity 3DL2*(002, 007/010, 015) has accounted for 12.09% of the 306 tested samples. The remaining 5 ambiguities were (2DL5A*001, 2DL5B*006/2DL5A*012, 2DL5B*008), 3DL3*(001, 010/009, 048), 3DL2*(007, 008/016, 027), 3DL3*(00801, 048/01001, 026) and 3DL3*(00802, 048/01002, 026) have accounted for 5.88% (18/306), 3.59% (11/306), 2.29% (7/306), 1.31% (4/306) and 1.31% (4/306) of all samples, respectively. For two ambiguities (2DL5A*001, 2DL5B*006/2DL5A*012, 2DL5B*008) and 3DL2*(007, 008/016, 027) subjected to group-specific PCR and re-sequencing, only one demonstrable genotype was identified, While for in each of other four ambiguities subjected to group-specific PCR and re-sequencing, two different genotypes were identified., Conclusion: An efficient approach by group-specific PCR and sequencing retest has been established to clarify the ambiguities during SBT testing for functional KIR framework genes, which may have a broad application in KIR sequencing-based typing.

Objective: To develop an assay for cDNA cloning and haplotype sequencing of KIR2DL1 framework gene and determine the genotype of an ethnic Han from southern China., Methods: Total RNA was isolated from peripheral blood sample, and complementary DNA (cDNA) transcript was synthesized by RT-PCR. The entire coding sequence of the KIR2DL1 framework gene was amplified with a pair of KIR2DL1-specific PCR primers. The PCR products with a length of approximately 1.2 kb were then subjected to cloning and haplotype sequencing., Results: A specific target fragment of the KIR2DL1 framework gene was obtained. Following allele separation, a wild-type KIR2DL1*00302 allele and a novel variant allele, KIR2DL1*031, were identified. Sequence alignment with KIR2DL1 alleles from the IPD-KIR Database showed that the novel allele KIR2DL1*031 has differed from the closest allele KIR2DL1*00302 by a non-synonymous mutation at CDS nt 188A>G (codon 42 GAG>GGG) in exon 4, which has caused an amino acid change Glu42Gly. The sequence of the novel allele KIR2DL1*031 was submitted to GenBank under the accession number KP025960 and to the IPD-KIR Database under the submission number IWS40001982. A name KIR2DL1*031 has been officially assigned by the World Health Organization (WHO) Nomenclature Committee., Conclusion: An assay for cDNA cloning and haplotype sequencing of KIR2DL1 has been established, which has a broad applications in KIR studies at allelic level.

Objective: To investigate the effects of the furin inhibitor α1-PDX on the growth, invasion, and tumorigenicity of cervical cancer cells and explore the mechanisms., Methods: The changes in the growth, migration and invasion of α1-PDX-transfected HeLa cells were observed using MTT assay, Boyden migration and invasion assay. The protein levels of furin and MT1-MMP were measured using Western blotting and furin activity was detected by enzyme activity assay in the transfected cells. HeLa cells were seeded subcutaneously in nude mice and the tumor volume changes were recorded., Results: Compared with the control cells, α1-PDX-treated cells showed a significant growth inhibition by 18.4% at 24 h (P<0.01) with obviously lowered migration ability and cell invasiveness (P<0.01). Treatment with α1-PDX significantly reduced furin enzyme activity and MTI-MMP protein levels in HeLa cells. In nude mice, α1-PDX-treated HeLa cells exhibited a delayed and lowered tumorigenicity with reduced size of the tumors., Conclusion: α1-PDX can inhibit the growth, metastasis and tumorigenicity of HeLa cells, the mechanism of which may involve a decreased furin activity and MTI-MMP expression.