Etiological characteristics of chlamydia trachoma conjunctivitis of Primary Boarding School students in the Qinghai Tibetan area

The aim of this study was to investigate the etiological characteristics of Chlamydia trachomatis conjunctivitis among resident students at primary schools in the Qinghai Tibetan area in order to understand the distribution of C. trachomatis and other pathogenic microorganisms, to detect the isolation rate of infectious pathogens, and to provide an evidence for further targeted efforts in the prevent of sporadic trachoma efforts. From two primary schools in Qinghai Province, ocular samples from 35 students who were clinically diagnosed as trachoma cases and 60 normal controls were obtained by swabbing their upper eyelids and lower conjunctival sacs. Samples were preserved at 4°C and airlifted to Beijing Tongren Hospital within 24 h. Real-time polymerase chain reaction(RT-PCR) was used to screen for C. trachomatis, and nested PCR was used to amplify a fragment of the omp A gene for serotype confirmation. Bacterial cultivation and sensitivity tests were conducted based on the 2015 version of the Clinical and Laboratory Standards Institute. Adenovirus, herpes simplex virus, cytomegalovirus, and Epstein-Barr virus were screened by RT-PCR. Among the 35 students with trachoma, 8 came from the Jianshetang Primary School and 27 came from the Central Primary School. Two novel C. trachomatis B serotypes(Gen Bank accession numbers KU737520 and KU737521) were detected based on a sequence analysis of the omp A gene. Single C. trachomatis infections accounted for 42.86%(9/21) of the cases, and infections with multiple bacteria, particularly Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, and Streptococcus pneumoniae, accounted for the remaining 57.14%(12/21). Of the 14 C. trachomatis-negative samples, one was positive for adenoviral infection(serotype D) and 13 were positive for bacterial infections(H. influenzae, M. catarrhalis, S. pneumoniae, S. aureus, streptococci other than S. pneumoniae, Staphylococcus epidermidis, Corynebacterium, and Arthrobacterium). In addition to C. trachomatis, the other bacteria and virus that were detected in the boarding students of primary schools in the Qinghai Tibetan area should be emphasized in trachoma prevention and control.     

莲品种DNA指纹图谱的构建

为了克服单纯依据形态特性鉴定品种的局限性, 我们开展了莲品种DNA指纹图谱构建研究, 旨在对其品种的快速准确鉴定及专利权保护等起一定作用。本研究以圆明园保存的72个莲品种为实验材料, 用来自不同地点的1,409份野生莲(Nelumbo nucifera)和58份美洲黄莲(N. lutea)群体样本作遗传背景参照。从104对核微卫星引物(nSSR)中筛选出15对, 从17对叶绿体微卫星(cpSSR)引物中筛选出2对, 共17对引物作为72个莲品种DNA指纹鉴定的条码。15对nSSR引物共检测到94个等位基因(平均6.27个), 其中11个属于美洲黄莲, 65个属于野生莲, 18个不能区分; 多态信息含量(PIC)介于0.3899-0.8023之间 (平均0.5748)。2对cpSSR引物共检测到13个单倍型, 其中9个属于野生莲, 4个属于美洲黄莲。全部17对引物标记结果显示, 共有19个品种含有美洲黄莲遗传组分, 其中8个母系来源于美洲黄莲; 有36个品种(涉及12对引物)具有至少1个特有基因型; 最少8对引物组合可完全区分开68个品种。有2组共4个品种组内全部17对引物均不能区分。本研究通过核心引物组合法使68个莲品种获得特异性DNA指纹。推荐13对nSSR和2对cpSSR共15对引物作为莲品种鉴定的核心条码, 并建议将形态特征与DNA指纹相结合作为莲品种的鉴定标准。     

Nuclear fast red‐based colorimetric sensors for sensitive and selective detection of Ag ions

The reduction of nuclear fast red (NFR) stain by sodium tetrahydroboron was catalyzed in the presence of silver ions (Ag⁺). The fluorescence properties of reduced NFR differed from that of NFR. The product showed fluorescence emission at 480 nm with excitation at 369 nm. Furthermore, the fluorescence intensity of the mixture increased strongly in the presence of Ag⁺ and Britton–Robinson buffer at pH 4.78. There was a good linear relationship between increased fluorescence intensity (ΔI) and Ag⁺ concentration in the range 5.0 × 10^?9 to 5.0 × 10^?8 M. The correlation coefficient was 0.998, and the detection limit (3σ/k) was 1.5 × 10^?9 M. The colour of the reaction system changed with variation in Ag⁺ concentration over a wide range. Based on the colour change, a visual semiquantitative detection method for recognition and sensing of Ag⁺ was developed for the range 1.0 × 10^?8 to 5.0 × 10^?4 M, with an indicator that was visible to the naked eye. Therefore, a sensitive, simple method for determination of Ag⁺ was developed. Optimum conditions for Ag⁺ detection, the effect of other ions and the analytical application of Ag⁺ detection of synthesized sample were investigated.     

高产雷帕霉素的游动放线菌菌种的选育

以游动放线菌(Actinoplanes)BCLP-016为出发菌株,采用常压室温等离子体(ARTP)诱变技术对其孢子进行处理,并将三个不同时间处理的孢子悬液混合。稀释涂布后,根据菌株菌落形态挑取部分单菌落进行初筛,经发酵复筛后,筛选得到了一株雷帕霉素高产菌株ARTP-039,其雷帕霉素的产量可达到369.39mg/L,较出发菌株BCLP-016的产量256.86 mg/L,提高了43.81%。以筛选出的ARTP-039高产菌为出发菌株,进行传统的紫外诱变,选取高、中、低三个致死率相对应的时间对其孢子悬液进行处理,并基于核糖体工程的理论选取了链霉素、庆大霉素、利福平、氯霉素和红霉素五种抗性物质,进行抗性初筛。发酵复筛后,最终筛选得到了一株雷帕霉素高产菌株St8+Gen6+Rif9+Chl3+Er4-015,该菌株同时具有五种抗性。该菌株的摇瓶实验结果表明,发酵7d后,其雷帕霉素的产量可达到589.79mg/L,较出发菌株BCLP-016的产量,提高了129.61%,且其遗传稳定性良好。     

Diblock glycopolymers promote colloidal stability of polyplexes and effective pDNA and siRNA delivery under physiological salt and serum conditions

A series of glycopolymers composed of 2-deoxy-2-methacrylamido glucopyranose (MAG) and the primary amine-containing N-(2-aminoethyl) methacrylamide (AEMA) were synthesized via aqueous reversible addition-fragmentation chain transfer (RAFT) polymerization. The colloidal stability of the polyplexes formed with three diblock glycopolymers and pDNA was assessed using dynamic light scattering, and the polyplexes were found to be stable against aggregation in the presence of salt and serum over the 4 h time period studied. Delivery experiments were performed in vitro to examine the cellular uptake, transfection efficiency, and cytotoxicity of the glycopolymer/pDNA polyplexes in cultured HeLa cells and the diblock copolymer with the shortest AEMA block was found to be the most effective. Additionally, the ability of the diblock glycopolymers to deliver siRNA to U-87 (glioblastoma) cells was screened, and the diblock copolymer with the longest AEMA block was found to have gene knockdown efficacy similar to Lipofectamine 2000.     

Aerobic denitrification by novel isolated strain using NO-₂-N as nitrogen source

Biological denitrification reaction can be achieved under aerobic environment. Few aerobic denitrifiers using nitrite as sole nitrogen source were identified. Using nitrite as the sole nitrogen source, this work assessed the denitrification activity of yy7, an aerobic heterotrophic denitrifier identified as Pseudomonas sp. (94% similarity) by 16S rRNA sequencing analysis. The logistic equation describes the cell growth curve, yielding a generation time of 2.9h at an initial 18 mg l(-1)NO(-)?-N. Reduction of NO(-)?-N was primarily achieved during its logarithmic growth phase, and was accompanied by an increase in suspension pH and near complete consumption of dissolved oxygen. Three genes relating to nirK, norB, and nosZ were noted to involve in isolate strain. Isolate yy7 can survive and remove up to 40 mg l(-1)NO(-)?-N and, hence, can be applied as an effective aerobic denitrifier during simultaneous nitrification and denitrification via nitrite processes.     

Abundance and functional roles of intrinsic disorder in allergenic proteins and allergen representative peptides

The pathological process of allergies generally involves an initial activation of certain immune cells, tied to an ensuing inflammatory reaction on renewed contact with the allergen. In IgE-mediated hypersensitivity, this typically occurs in response to otherwise harmless food- or air-borne proteins. As some members of certain protein families carry special properties that make them allergenic, exploring protein allergens at the molecular level is instrumental to an improved understanding of the disease mechanisms, including the identification of relevant antigen features. For this purpose, we inspected a previously identified set of allergen representative peptides (ARPs) to scrutinize protein intrinsic disorder. The resulting study presented here focused on the association between these ARPs and protein intrinsic disorder. In addition, the connection between the disorder-enriched ARPs and UniProt functional keywords was considered. Our analysis revealed that ～ 20% of the allergen peptides are highly disordered, and that ～ 77% of ARPs are either located within disordered regions of corresponding allergenic proteins or show more disorder/flexibility than their neighbor regions. Furthermore, among the subset of allergenic proteins, ～ 70% of the predicted molecular recognition features (MoRFs that consist of short interactive disordered regions undergoing disorder-to-order transitions at interaction with binding partners) were identified as ARPs. These results suggest that intrinsic disorder and MoRFs may play functional roles in IgE-mediated allergy.     

CRISPR Cas9- and Cas12a-mediated gusA editing in transgenic blueberry

To develop an effective genome editing tool for blueberry breeding, CRISPR-Cas9 and CRISPR-Cas12a were evaluated for their editing efficiencies of a marker gene, beta-glucuronidase (gusA), which was previously introduced into two blueberry cultivars each a single-copy transgene. Four expression vectors were built, with CRISPR-Cas9 and CRISPR-Cas12a each driven by a 35S promoter or AtUbi promoter. Each vector contained two editing sites in the gusA. These four vectors were respectively transformed into the leaf explants of transgenic gusA blueberry and the resulting transgenic calli were induced under hygromycin selection. GUS staining showed that some small proportions of the hygromycin-resistant calli had non-GUS stained sectors, suggesting some possible occurrences of gusA editing. We sequenced GUS amplicons spanning the two editing sites in three blueberry tissues and found about 5.5% amplicons having editing features from the calli transformed with the 35S-Cas9 vector. Further, we conducted a second round of shoot regeneration from leaf explants derived from the initial Cas9- and Cas12a-containing calli (T₀) and analyzed amplicons of the target editing region. Of the newly induced shoots, 15.5% for the 35S-Cas9 and 5.3% for the AtUbi-Cas9 showed non-GUS staining, whereas all of the shoots containing the Cas12a vectors showed blue staining. Sanger sequencing confirmed the editing-induced mutations in two representative non-GUS staining lines. Clearly, the second round of regeneration had enriched editing events and enhanced the production of edited shoots. The results and protocol described will be helpful to facilitating high-precision breeding of blueberries using CRISPR Cas technologies.

     

一株C3形态多重耐药大肠杆菌噬菌体生物学特性和基因组分析

【目的】多重耐药菌的出现对公共卫生安全构成严重威胁,本研究分离多重耐药大肠杆菌噬菌体,研究其生物学特性和基因组特征,为耐药菌的噬菌体疗法提供理论依据。【方法】使用双层平板法从污水样本中分离纯化大肠杆菌噬菌体;磷钨酸染色后通过透射电镜观察形态;测定其宿主范围,测定温度和pH稳定性、一步生长曲线和体外抑菌效果等生物学特性;体内抑菌试验评估噬菌体对多重耐药大肠杆菌N1203-1Af感染的大蜡螟幼虫的保护作用;基于全基因组测序对其基因组特点进行分析。【结果】本研究分离共得到5株大肠杆菌噬菌体,分别命名为pEC-S163-2.1、pEC-S163-2.2、pEC-M1167-5Ar.1、pEC-m1291-2Dr.1和pEC-N1203-2Af.1;电镜结果显示噬菌体pEC-N1203-2Af.1属于短尾噬菌体中罕见的C3形态型,头部较长,长是宽的2–3倍;pEC-N1203-2Af.1可裂解受试15株大肠杆菌中的3株;感染10 min后进入指数增长期,–20-50℃、pH值为4.0–10.0的环境下均能够保持稳定活性;大蜡螟幼虫感染大肠杆菌N1203-2Af后噬菌体pEC-N1203-2Af....     

Sleep Quality of Patients with Differentiated Thyroid Cancer

Objective

We aimed to measure prevalence of sleep disturbance in patients with differentiated thyroid cancer (DTC) by calculating Pittsburgh Sleep Quality Index (PSQI), and compare these data with patients with benign thyroid nodules or normal participants.

Methods

Three groups of patients participated in this cross-sectional study. In the first group, 162 patients with DTC received total thyroidectomy, and then ¹³¹I therapy. The second group consisted of 84 patients with benign thyroid nodules, who received partial thyroidectomy. The third group was 78 normal healthy control cases. PSQI was used to assess the sleep quality. Inter-group differences were analyzed by Kruskal-Wallis test or independent samples T test. χ² test was also used to check prevalence differences of poor sleep quality among the groups. Differences of PSQI score and poor sleep quality prevalence before and after ¹³¹I therapy in the same group of DTC participants were analyzed by paired T test and Mcnemar''s test.

Results

Higher PSQI score (7.59 ± 4.21) and higher rate of poor sleep quality (54.32%) were shown in DTC patients than in any other group. After ¹³¹I therapy, PSQI score and prevalence of poor sleep quality in DTC patients increased significantly to 8.78 ± 4.72 and 70.99%. Then DTC patients were divided into two subgroups based on their metastatic status. DTC patients with metastasis (87/162 cases, 53.70%) had significantly higher PSQI score (10.87 ± 5.18) and higher prevalence of poor sleep quality (79.31%).

Conclusion

DTC patients suffer from sleep disturbance, ¹³¹I therapy and awareness of metastatic status could worsen sleep problem. Psychological fear of cancer, nuclear medicine therapy and metastasis could be one major underlying reason. Longitude and interventional studies are necessary for further investigations.