Stromal cell‐derived factor‐1/Exendin‐4 cotherapy facilitates the proliferation,migration and osteogenic differentiation of human periodontal ligament stem cells in vitro and promotes periodontal bone regeneration in vivo

ObjectivesStromal cell‐derived factor‐1 (SDF‐1) actively directs endogenous cell homing. Exendin‐4 (EX‐4) promotes stem cell osteogenic differentiation. Studies revealed that EX‐4 strengthened SDF‐1‐mediated stem cell migration. However, the effects of SDF‐1 and EX‐4 on periodontal ligament stem cells (PDLSCs) and bone regeneration have not been investigated. In this study, we aimed to evaluate the effects of SDF‐1/EX‐4 cotherapy on PDLSCs in vitro and periodontal bone regeneration in vivo.MethodsCell‐counting kit‐8 (CCK8), transwell assay, qRT‐PCR and western blot were used to determine the effects and mechanism of SDF‐1/EX‐4 cotherapy on PDLSCs in vitro. A rat periodontal bone defect model was developed to evaluate the effects of topical application of SDF‐1 and systemic injection of EX‐4 on endogenous cell recruitment, osteoclastogenesis and bone regeneration in vivo.ResultsSDF‐1/EX‐4 cotherapy had additive effects on PDLSC proliferation, migration, alkaline phosphatase (ALP) activity, mineral deposition and osteogenesis‐related gene expression compared to SDF‐1 or EX‐4 in vitro. Pretreatment with ERK inhibitor U0126 blocked SDF‐1/EX‐4 cotherapy induced ERK signal activation and PDLSC proliferation. SDF‐1/EX‐4 cotherapy significantly promoted new bone formation, recruited more CXCR4⁺ cells and CD90⁺/CD34^‐ stromal cells to the defects, enhanced early‐stage osteoclastogenesis and osteogenesis‐related markers expression in regenerated bone compared to control, SDF‐1 or EX‐4 in vivo.ConclusionsSDF‐1/EX‐4 cotherapy synergistically regulated PDLSC activities, promoted periodontal bone formation, thereby providing a new strategy for periodontal bone regeneration.     

Association of myostatin deficiency with collagen related disease-umbilical hernia and tippy toe standing in pigs

Transgenic Research - Herein, we investigate the high incidence of umbilical hernia and tippy-toe standing and their underlying changes in gene expression and proliferation in myostatin knockout...     

Faecalicatena faecalis sp. nov., a moderately alkaliphilic bacterial strain isolated from swine faeces

An obligately anaerobic, Gram-stain-positive, non-motile, non-spore-forming and rod-shaped strain AGMB00832^T was isolated from swine faeces. Phylogenetic analysis based on the 16S rRNA gene, together with the housekeeping genes, gyrB and rpoD, revealed that strain AGMB00832^T belonged to the genus Faecalicatena and was most closely related to Faecalicatena orotica KCTC 15331^T. In biochemical analysis, strain AGMB00832^T was shown to be negative for catalase, oxidase and urease. Furthermore, the isolate was positive for β-glucosidase, β-glucuronidase, glutamic acid decarboxylase, proline arylamidase, acid phosphatase and naphthol-AS-BI-phosphohydrolase. The major cellular fatty acids (>?10%) of the isolate were C_14:0, C_16:0 and C_18:1ω11t DMA. Based on the whole genome sequence analysis, the DNA G?+?C content of strain AGMB00832^T was 44.2 mol%, and the genome size and numbers of rRNA and tRNA genes were 5,175,159 bp, 11 and 53, respectively. The average nucleotide identity and digital DNA–DNA hybridization values between strain AGMB00832^T and related strains were ≤?77.4 and 22.5%, respectively. Furthermore, the genome analysis revealed the presence of genes for alkaline shock protein 23 and cation/proton antiporters, which may facilitate growth of strain AGMB00832^T in alkaline culture condition. On the basis of polyphasic taxonomic approach, strain AGMB00832^T represents a novel species within the genus Faecalicatena, for which the name Faecalicatena faecalis sp. nov. is proposed. The type strain is AGMB00832^T (=?KCTC 15946^T?=?NBRC 114613^T).

     

Stable polymer bilayers for protein channel recordings at high guanidinium chloride concentrations

The use of chaotropic reagents is common in biophysical characterization of biomolecules. When the study involves transmembrane protein channels, the stability of the protein channel and supporting bilayer membrane must be considered. In this letter, we show that planar bilayers composed of poly(1,2-butadiene)-b-poly(ethylene oxide) diblock copolymer are stable and leak-free at high guanidinium chloride concentrations, in contrast to diphytanoyl phosphatidylcholine bilayers, which exhibit deleterious leakage under similar conditions. Furthermore, insertion and functional analysis of channels such as α-hemolysin and MspA are straightforward in these polymer membranes. Finally, we demonstrate that α-hemolysin channels maintain their structural integrity at 2 M guanidinium chloride concentrations using blunt DNA hairpins as molecular reporters.     

Two Helminthic Cases of Human Mummy Remains from Joseon-Period Graves in Korea

Our previous research on coprolite specimens from the mummies of Joseon Dynasty (1392–1910 CE) has revealed various species of parasite eggs. Herein, we added 2 new helminthic cases of human remains from Joseon-period graves in the Republic of Korea (Korea). The organic materials precipitated on the hip bones of 2 half-mummied cases (Goryeong and Gwangmyeong cases) were collected, rehydrated, and examined by a microscope. In the sample from Goryeong-gun (gun=County), ova of Trichuris trichiura, Clonorchis sinensis, and Metagonimus spp. were detected, and eggs of T. trichiura and A. lumbricoides were found from the sample of Gwangmyeong-si (si=City). By adding this outcome to the existing data pool, we confirm our previous estimates of Joseon-period parasite infection rates. The overall rates of A. lumbricoides, T. trichiura, and C. sinensis decreased dramatically from Joseon to the modern period. In Goryeong mummy specimen, we also found Metagonimus spp. eggs that has rarely been detected in archaeological samples so far.     

安徽北部地区恶性肿瘤人群卡波氏肉瘤相关疱疹病毒血清学分析

卡波氏肉瘤相关疱疹病毒是一种新发现的γ疱疹病毒(Kaposi'ssarcoma-associated herpesvirus,KSHV).在中国新疆,KSHV感染率比较高,KSHV在免疫缺陷患者和静脉吸毒者中感染率也比在普通人群中高.为了进一步研究KSHV在安徽北部地区恶性肿瘤人群中的感染率和高风险因素,初步探讨KSHV与肿瘤的发生之间相关性,研究KSHV的高发人群特点,本研究选用KSHV病毒重组蛋白ORF65、ORF 73和K8.1为抗原,利用酶联免疫吸附实验(ELISA)对500份恶性肿瘤患者血清样本及200份健康体检人群血清样本进行KSHV抗体检测,分析KSHV的感染率及危险因素.结果显示500例肿瘤患者KSHV阳性总数170例,总阳性率为34％,200份健康人群KSHV阳性总数22例,总阳性率为11％,肿瘤人群KSHV阳性率明显高于健康人群(P＜0.001).其中肺癌、肝癌、结肠癌、宫颈癌、乳腺癌样本KSHV阳性率分别为36.4％,34.1％,41.7％,28.6％,30.3％,此5组肿瘤组KSHV阳性率也分别高于健康人群,都具有统计学意义(P＜0.001).但5组肿瘤样本之间KS-HV阳性率无明显差异(P＞0.05),且各组肿瘤样本分别与性别、乙肝五项、丙肝之间无统计学意义(P＞0.05).本研究结果提示安徽北部地区恶性肿瘤患者KSHV抗体阳性率显著高于中国普通人群总体KSHV抗体阳性率,证明KSHV在恶性肿瘤人群中呈现较高比例的分布.     

Congruent spatial patterns of species richness and phylogenetic diversity in karst flora: Case study of Primulina (Gesneriaceae)

The karst landform in southern China is renowned for its high levels of species diversity and endemism. Globally, karst ecosystems are under threat from unsustainable anthropogenic disturbance and climate changes and are among the most threatened ecosystems worldwide. In this study, we used the typical karst endemic genus in southern China, Primulina Hance, as a model to identify areas within the karst landform with high diversity and to investigate congruence between phylogenetic and species‐based measures of diversity. Using phylogenetic information and species distribution data, we measured geographical patterns of diversity with four metrics: species richness (SR), corrected weighted endemism (CWE), phylogenetic diversity (PD), and phylogenetic endemism (PE). Our results revealed a high spatial congruence among SR, PD, and PE, with hotspot areas identified in the Nanling Mountains (i.e., north Guangdong and northeast Guangxi) and southeast Yungui Plateau (i.e., north and southwest Guangxi), whereas the hotspots of CWE are comparatively uniform throughout the geographic extent. The categorical analysis of neo‐ and paleoendemism identified a pattern of mixed neo‐ and paleoendemism in numerous grid cells, suggesting that karst areas in southern China have acted as both “museums” and “cradles” of plant evolution. Conservation gap analysis of hotspots revealed that the majority of prioritized hotspots (>90%) of the genus are outside of protected areas, therefore indicating the limited effectiveness of national nature reserves for the karst flora. Overall, our results suggest that the karst flora merits more conservation attention and SR can be an effective surrogate to capture PD in conservation planning.     

澳洲坚果MtMADS1-like基因的克隆与表达分析

MADS～box家族基因广泛分布于植物中,在植物花发育的整个阶段起着至关重要的作用.为了探索MADS-box基因在澳洲坚果花发育过程中的分子机理,本研究以澳洲坚果'695'为试材,采用RT-PCR及RACE技术克隆获得澳洲坚果MADS-box类转录因子基因cDNA全长,命名MtMADS1-like(GenBank登录号:MK491608).该基因全长967 bp,开放阅读框ORF长672 bp,编码223个氨基酸,5'-UTR和3'-UTR分别为58 bp和237 bp.序列分析表明,MtMADS1-like具有保守的MADS-box结构域(MADS-MEF2-like)和半保守的K-box结构域,属于Type Ⅱ型MADS-box家族基因.进化分析表明,MtMADS1-like与其他植物中MADS-box蛋白具有较高的同源性,且与猴面花(Erythranthe guttata)MADS-box家族中SVP254的同源性高达67.10％,亲缘关系最近.生物信息学分析表明MtMADS1-like属于不稳定的亲水性蛋白,不具备信号肽,属于非分泌蛋白,α-螺旋和无规则卷曲构成了二级结构的主要蛋白框架,三级结构中MADS-box结构域和K-box形成该蛋白的核心结构,并且作为转录因子定位于细胞核.qPCR分析表明,MtMADS1-like基因在不同的澳洲坚果品种中差异表达,在品种'333'中表达量最高,在品种'344'中表达量最低.研究结果为进一步验证MtMADS1-like的功能及阐明澳洲坚果花发育和开花调控的分子机制奠定了基础.