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Objectives: Three different hypotheses proposed via the controversial evidence from cultural, anthropological and uniparental genetic analysis respectively stated that Tanka people probably originated from Han Chinese, ancient Baiyue tribe, or the admixture of them. Therefore, the genetic origin and admixture history of the Tanka people, an isolated 'Gypsies in water' in the coastal region of Southeast China, are needed to be genetically clarified. Materials and methods: To elucidate the genetic origin of the Southeast Tanka people and explore their genetic relationship with surrounding indigenous Tai-Kadai and Austronesian people and Neolithic-to-historic ancients from the Yellow River Basin (YRB) and Fujian, we conducted a large-scale population genomic study among 1498 modern and ancient Eurasians, in which 73 Tanka and 4 Han people were first reported here. Both allele-shared and haplotype-based statistical methods were used here, including PCA, ADMIXTURE, f-statistics, ALDER, qpGraph-/TreeMix and qpAdm/qpWave, ChromoPainter and FineSTRUCTURE. Results: We found a specific genetic cline in PCA plots and detected the Tanka-specific homogeneous ancestry in model-based ADMIXTURE results, suggesting differentiated demographic history between Tanka and surrounding Hans. Formal tests based on sharing allele patterns showed a close relationship between Tanka people and Han Chinese, but the Tanka population harbored more southern East Asian ancestry related to Austronesian and Tai-Kadai people compared with southern Hans. Besides, the reconstructed differentiated demographic history revealed that southern Xinshizhou Tanka harbored more ancestry related to the Tai-Kadai or coastal ancient Neolithic to Bronze Age East Asians compared with northern Shacheng Tanka. The qpGraph-/TreeMix-based phylogenetic framework, qpAdm/qpWave-based admixture modeling and FineSTRUCTURE-based dendrogram among ancient northern and southern East Asians further demonstrated that the primary ancestry of modern Tanka derived from ancient millet farmers in the YRB with additional admixture from multiple southern East Asian sources. Discussion: Sharing ancestry estimated from the f-statistics and sharing haplotypic landscape inferred from the ChromoPainter and FineSTRUCTURE showed that Southeast Tanka people not only had a close genetic relationship with both Northern Hans and YRB millet farmers but also possessed more southern East Asian ancestry related to Austronesian, Tai-Kadai and Hmong-Mien people. Our genomic data and fitted admixture models supported modern Tanka originated from ancient North China and obtained additional gene flow from ancient southern East Asians in the processes of southward migrations.

This paper aims to explore the challenge of the design of over one-kilometer-long span road-rail cable-stayed bridge. Because of the large live load and the weight of the structure itself, it has important theoretical significance and engineering application value to study the design parameters of the long Road-Rail cable-stayed bridge with a main span of over 1000 m. The main content of this paper is to study the Steel Road-Rail Cable-stayed Bridge with a main span of 1200 m. The finite element model is established by large-scale analysis software to calculate the response of the structure under load. Based on the calculation results, the rationality of long-span cable-stayed bridge are preliminarily researched. Wind and seismic loads are not considered.

The main content of this paper is to study the Steel Road-Rail Cable-stayed Bridge with a main span of 1200m. The finite element model is established by large-scale analysis software to calculate the response of the structure under load. Based on the calculation results, the rationality of long-span cable-stayed bridge are preliminarily researched in this paper.

Background Comprehensive and accurate detection of human platelet antigens (HPAs) plays a significant role in diagnosis and prevention of the platelet (PLT) alloimmune syndromes and ensuring clinical safety of patients undergoing PLT transfusion. The majority of the available methods are incapable of performing high-throughput simultaneous detection of HPA-1 to -16, and the accuracy of many methods needs to be further enhanced. Study Design and Methods We have developed a new HPA-genotyping method for simultaneous detection of HPA-1 to -16 based on suspension array technology. A total of 216 samples from Chinese Han donors in Xi'an were genotyped using the developed method, and all the samples again were genotyped using polymerase chain reaction (PCR) sequence-based typing (PCR-SBT), which is considered the gold standard. Results All 216 samples were successfully genotyped for HPA-1 to -16 using both our method and PCR-SBT. Results showed that the genotype and allele frequencies obtained using our method were fully consistent with those obtained using PCR-SBT. Conclusion Our method provides accurate, high-throughput, and simultaneous genotyping of HPA-1 to -16 and will serve as the foundation for large-scale clinical genotyping of HPAs and for the establishment of an HPA-typed PLT donor registry.

Trichosanthin (TCS) is a type I ribosome-inactivating protein (RIP) possessing multiple pharmacological properties. One of its interesting properties is to inhibit human immunodeficiency virus (HIV) replication but its strong immunogenicity has limited the repeated clinical administration. To map the antigenic determinants and reduce the immunogenicity of TCS, two potential antigenic sites (YFF81-83 and KR173-174) were identified by computer modeling, and then three TCS mutants namely TCS(YFF81-83ACS), TCS(KR173-174CG), and TCS(YFF-KR) were constructed by site-directed mutagenesis. The RI activity and DNase-like activity of the three constructed TCS mutants were similar to natural TCS but with much lower immunogenicity. Results suggested that the two selected sites are all located at or near the antigenic determinants of TCS. In toxicity studies, the LD(50) of the three TCS mutants was not different from natural TCS. These findings would be useful in designing a better therapeutic agent for AIDS.

Comprehensive and accurate detection of human platelet antigens (HPAs) plays a significant role in diagnosis and prevention of the platelet (PLT) alloimmune syndromes and ensuring clinical safety of patients undergoing PLT transfusion. The majority of the available methods are incapable of performing high-throughput simultaneous detection of HPA-1 to -16, and the accuracy of many methods needs to be further enhanced.We have developed a new HPA-genotyping method for simultaneous detection of HPA-1 to -16 based on suspension array technology. A total of 216 samples from Chinese Han donors in Xi'an were genotyped using the developed method, and all the samples again were genotyped using polymerase chain reaction (PCR) sequence-based typing (PCR-SBT), which is considered the gold standard.All 216 samples were successfully genotyped for HPA-1 to -16 using both our method and PCR-SBT. Results showed that the genotype and allele frequencies obtained using our method were fully consistent with those obtained using PCR-SBT.Our method provides accurate, high-throughput, and simultaneous genotyping of HPA-1 to -16 and will serve as the foundation for large-scale clinical genotyping of HPAs and for the establishment of an HPA-typed PLT donor registry.

To observe the killing effect of irradiated peripheral blood mononuclear cells (PBMCs) at low dose combined with (-)-gossypol on cultured human prostate cancer LNCaP cells.Human PBMCs were irradiated by gamma ray at 1 gray, the irradiation dose rate was 17 Gy/min. The experiments were divided into control group (LNCaP cells only), LNCaP cells with irradiated and non-irradiated PBMCs co-culture groups, (-)-gossypol treatment group, irradiated PBMCs and (-)-gossypol co-treatment group. Acridine orange/ethidium bromide (AO/EB) staining and MTT method were used to observe the killing effect of PBMCs and/or (-)-gossypol.The killing activity of irradiated PBMCs group and (-)-gossypol treatment group were obviously increased and were higher than that of non-irradiated group (P0.05). The killing activity of combined group was much higher than that of irradiated group and ApoG2 treatment group (P0.01).Irradiated PBMCs at low dose combined with (-)-gossypol can enhance the anti-tumor effects obviously.

Increasing evidence has demonstrated that EGCG possesses prooxidant potential in biological systems, including modifying proteins, breaking DNA strands and inducing the generation of reactive oxygen species. In the present study, the prooxidant effect of EGCG on erythrocyte membranes was investigated. SDS-PAGE and NBT-staining assay were utilized to detect the catechol-protein adducts that generated upon treating the membranes with EGCG. The results indicated that EGCG was able to bind covalently to sulfhydryl groups of membrane proteins, leading to the formation of protein aggregates with intermolecular cross-linking. We suggested that the catechol-quinone originated from the oxidation of EGCG acted as a cross-linker on which peptide chains were combined through thiol-S-alkylation at the C2- and C6-sites of the gallyl ring. EGC showed similar effects as EGCG on the ghost membranes, whereas ECG and EC did not, suggesting that a structure with a gallyl moiety is a prerequisite for a catechin to induce the aggregation of membrane proteins and to deplete membrane sulfhydryls. EDTA and ascorbic acid inhibited the EGCG-induced aggregation of membrane proteins by blocking the formation of catechol-quinone. The information of the present study may provide a fresh insight into the prooxidant effect and cytotoxicity of tea catechins.

To construct PEGylated trichosanthin (TCS) mutein and analyze its bioactivities, immunogenicity, acute toxicity, and pharmacokinetics.The potential antigenic determinant site YFF81-83 in the molecule of TCS was selected to undergo site-directed mutagenesis. Thus, a TCS mutein named TCS(YFF81-83ACS) was constructed and expressed in Escherichia coli of the line BL21 (DE3). Wild TCS (wTCS), TCSY(FF81-83ACS), and PEGylated TCS(YFF81-83ACS) (PEG- TCS(YFF81-83ACS)) of different concentrations were incubated with the supercoiled plasmid pUC19 to detect the DNAse activity, mixed with rabbit reticulocyte lysate to detect the ribosome inactivation activity, subcutaneously injected into 6 mice respectively to measure the serum IgG and IgE levels, intravenously injected into mice to observe the toxicity, and intravenously injected into SD rats to observe its -plasma half-life.The DNAse activity of the PEG-TCS(YFF81-83ACS) was similar to that of the wTCS. The ribosome inactivation activity of the PEG-TCS(YFF81-83ACS) was 1/9-1/8 of that of the wTCS (P0.05). The serum IgE and IgG levels of the PEG-TCS(YFF81-83ACS) were both significantly lower than those of the wTCS (both P0.05). The LD50 of the PEG-TCS(YFF81-83ACS) was 1.8 times that of the wTCS (P0.05). The mean residence time and plasma half-life of the PEG-TCS(YFF81-83ACS) were significantly increased and its plasma clearance was significantly decreased (all P0.05).Site-directed mutagenesis and PEGylation of TCS provide a new approach for reconstructing TCS.