母亲唾液中2种牙周致病菌对胎儿的影响

目的检测早产低体重儿（pretermlowbirthweight,PLBW）与正常体重儿（normalbirthweight,NBW）母亲的牙周临床状况及唾液中牙龈卟啉单胞菌（porphyromonasgingivalis,Pg）和直形弯曲菌（campylobacterrectus,Cr）检出率,探讨2种牙周病致病菌与PLBW发生的关系。方法选取北京四所医院产后1～1．5年的母亲99人,PLBW（试验组）母亲64人,NBW（对照组）母亲35人,收集母亲唾液样本,行全口牙周检查记录探诊深度（probingdepth,PD）、菌斑指数（plaqueindex,PLI）、出血指数（bleedingindex,BI）及临床附着丧失（clinicalattachmentloss,CAL）。用PCR检测唾液中的P岔和Cr;根据赡、Cr检出与否分为％、Cr阳性组、阴性组。结果（1）PLBW和NBW牙周临床指标及与Pg、cr水平：PLBW和NBW组CAL分别（0．06,0．62）mm（25％,75％）、（0．00,0．18）mm（25％,75％）,差异有统计学意义;PLBW组心检出58人的PD2．49±2.0．37;未检出5人的PD2．03±0．54,差异有统计学意义,％检出率为92．06％;NBW组唯检出28人的PD（2．47±0．35）mm,未检出7人的PD（1．91±0．35）mm,差异有统计学意义,赡检出率为80％。PLBW与NBW的瞻检出率差异无统计学意义。PLBW组cr检出55人检出率为87．30％,检出与未检出之间4项临床指标差异均无统计学意义。NBW组D检出率为91．4％,PLBW与NBW间D检出率差异无统计学意义。（2）P譬、Cr阳性组与阴性组间临床指标及与PLBW关系：Pg阳性组86人,阴性组12人,两组4项临床指标分别为PD（2．48±0．36）mm,（1．96±0．40）mm;PLI1．71±0．46,1．37±0．38;BI（1．82,3．02）（25％,75％）,（1．12,2．29）（25％,75％）;CAL（0．03,0．56）ITIm（25％,75％）,（0．00,0．11）mm（25％,75％）唯阳性组新生儿体重为（2482,78±833．85）g,阴性组为（3172．50±1190．1）g,差异均有统计学意义。cr阳性88人,D阳性11人,两组CAL值分别是（0．36±0．53）mm和（0．11±0．20）mm,差异有统计学意义,PD、PI、BI及新生儿体重差异均无统计学意义。结论珞、D在两组母亲唾液检出水平均高;Pg可能与PLBW发生有关;提示有必要进行孕前预防性牙周干预治疗。     

Analysis of subgingival microbiome of periodontal disease and rheumatoid arthritis in Chinese: A case-control study

ObjectivePeriodontitis (PD) and rheumatoid arthritis (RA) share similar pathogenesis. Evidences indicated that oral bacteria play an important role in the etiology of both diseases. For example, Porphyromonas gingvialis connect the two diseases through immune responses. We designed this study to compare bacterial diversity in RA, PD and healthy subjects and to investigate whether there are other oral bacteria play an potential role in linking the two diseases.MethodsThis study included 3 groups of Chinese participants who visited Sichuan Provincial People’s Hospital during August 2018 and March 2019. Subgingival plaques were collected from RA group (n = 54), PD group (n = 45) and normal group (n = 44). Illumina MiSeq was used to compare the composition of subgingival microbiota and analyze correlations between oral bacteria and both diseases.ResultsAlpha diversity Analysis reflected similar microbiome profile in RA, PD and healthy groups. But we found Treponema was significantly more abundant in the PD and RA groups than healthy group at each taxonomic level from the phylum down to the genus level. Porphyromonas, Prevotella, and Veilonella were significantly more abundant in RA while Streptococcus, Gemella, Planobacterium were verified the opposite results.ConclusionsWe found no significant group differences referent to either microbial diversity or richness. But we picked out Spirochaetes which may link the two diseases. Upper/lower regulation of some microbia in RA may remind us a direction to explore the role they play in pathogenesis.     

Salivary levels of inflammatory cytokines and their association to periodontal disease in systemic lupus erythematosus patients. A case-control study

Both Systemic Lupus Erythematosus (SLE) and periodontal disease (PD) present a similar immunological profile mainly characterized by altered cytokine levels. In this study we sought to investigate the salivary levels of inflammatory cytokines and their association with PD in SLE patients. 60 patients with SLE and 54 systemically healthy individuals underwent a full periodontal clinical examination. They were then grouped according to their periodontal status. Stimulated saliva was collected in order to evaluate the salivary levels of interferon (IFN-γ), Interleukin (IL)-10, IL-17, IL-1β, and IL-4. Systemically healthy individuals with periodontitis (group P) presented higher levels of cytokines when compared to systemically healthy individuals, with no periodontal disease (group S) (p < 0.05). Additionally, in the P group, patients presented similar levels of cytokines to those of the patients with SLE, regardless of the presence of PD (p > 0.05), for most of the analyzed cytokines. There was a positive correlation in SLE patients, including IL-1β and all periodontal clinical parameters (p < 0.05), and between IL-4 and gingival bleeding index and the presence of biofilm (p < 0.05). Thus, our results confirmed, that patients with PD showed higher salivary levels of cytokines and, in SLE patients, the increased levels of salivary cytokines were observed even in the absence of periodontitis. IL-1β and IL-4 salivary levels were also positively correlated with periodontal status indicating their potential as markers of the amount and extent of periodontal damage in patients with SLE.     

Detection of Dialister pneumosintes in the subgingival biofilm of subjects with periodontal disease

Dialister pneumosintes has been indicated as a potentially new periodontopathic species. This study evaluated the prevalence of this microorganism in saliva and subgingival biofilm from subjects with different periodontal conditions. Subgingival biofilm and saliva samples from 48 subjects with periodontal health (PH) and 116 patients with chronic periodontitis (CP) were obtained. DNA was extracted from the samples and the presence of D. pneumosintes was determined by PCR. Differences in clinical parameters and frequency of D. pneumosintes between groups were sought by Mann-Whitney, Chi-square and Fisher's exact tests. Overall, D. pneumosintes was detected in 47.8% of the biofilm samples, but only in 3% of saliva samples. CP patients presented a significantly greater mean prevalence of this species in sites with periodontal health and periodontal infection (43.5+/-7.4% and 62.1+/-6.4%, respectively) than PH subjects (29.4+/-7.9%) (Mann-Whitney; p<0.01). Moreover, significant associations between the prevalence of D. pneumosintes and pocket depth (p=0.001), attachment loss (p=0.001) and bleeding on probing (GLM, p=0.014) were observed after adjusting for age and gender. These findings corroborate the association of D. pneumosintes with periodontitis.     

Prevalence and distribution of bacteriophage φAa DNA in strains of Actinobacillus actinomycetemcomitans

Abstract φAa is a bacteriophage that was originally isolated by induction of a lysogenic strain of the oral bacterium Actinobacillus actinomycetemcomitans . Since the discovery of phage φAa , additional phages infecting several other strains of A. actinomycetemcomitans have been identified. To determine the prevalence of φAa or φAa -related temperate phages in this species, a φAa -specific DNA probe was prepared to screen for homologous sequences among 42 strains of A. actinomycetemcomitans . Fourteen (33%) of the 42 strains examined contained DNA sequences that hybridized with the phage φAa probe. A bacteriophage designated φAa ₃₃₃₈₄ was isolated by induction from one of the strains (ATCC 33384) that contained a sequence that hybridized with the φAa probe. The φAa probe hybridized with the DNA extracted from bacteriophage φAa ₃₃₃₈₄. The distribution of the phage φAa sequence among A. actinomycetemcomitans serotypes was 5/13 (38%) of the serotype a strains, 0/16 (0%) of the serotype b strains, and 9/13 (69%) of the serotype c strains. The results of this investigation suggest that the target sequence prepared from the phage φAa genome is fairly common in the A. actinomycetemcomitans chromosome, and that the sequence is distributed among the A. actinomycetemcomitans serotypes in a seemingly nonrandom manner.     

牙周组织再生术联合无托槽隐形矫治对牙周炎患者龈沟液炎症因子的影响

目的 探讨牙周组织再生术(PTR)联合无托槽隐形矫治对牙周炎患者龈沟液炎症因子的影响,为该类患者的治疗提供参考.方法 选取2017年3月至2019年3月我院收治的120例牙周炎患者为研究对象,依据随机数字表分为再隐组和再直组,每组60例.再隐组患者给予PTR联合无托槽隐形矫治,再直组患者给予PTR联合直丝弓矫治.比较两...     

Application of quantitative proteomic analysis using tandem mass tags for discovery and identification of novel biomarkers in periodontal disease

Periodontal disease is a bacterial infection that destroys the gingiva and surrounding tissues of the oral cavity. Gingival crevicular fluid (GCF) is extracted from the gingival sulcus and pocket. Analysis of biochemical markers in GCF, which predict the progression of periodontal disease, may facilitate disease diagnosis. However, no useful GCF biochemical markers with high sensitivity for detecting periodontal disease have been identified. Thus, the search for biochemical markers of periodontal disease is of continued interest in experimental and clinical periodontal disease research. Using tandem mass tag (TMT) labeling, we analyzed GCF samples from healthy subjects and patients with periodontal disease, and identified a total of 619 GCF proteins based on proteomic analysis. Of these, we focused on two proteins, matrix metalloproteinase (MMP)‐9 and neutrophil gelatinase‐associated lipocalin (LCN2), which are involved in the progression of periodontal disease. Western blot analysis revealed that the levels of MMP‐9 and LCN2 were significantly higher in patients with periodontal disease than in healthy subjects. In addition, ELISA also detected significantly higher levels of LCN2 in patients with periodontal disease than in healthy subjects. Thus, LC‐MS/MS analyses of GCF using TMT labeling led to the identification of LCN2, which may be a promising GCF biomarker for the detection of periodontal disease.     

Frameshift and double-amber mutations in the bacteriophage T4 uvsX gene: analysis of mutant UvsX proteins from infected cells

Summary The bacteriophage T4 uvsX gene encodes a 43 kDa, single-stranded DNA-dependent ATPase, double-stranded DNA-binding protein involved in DNA recombination, repair and mutagenesis. Mutants of uvsX have a DNA-arrest phenotype and reduced burst size. Western blot immunoassay of UvsX peptides made by a number of amber mutants revealed amber peptides ranging from 25–32 kDa. Wild-type UvsX protein was also detected in lysates of cells infected with uvsX amber mutants, suggesting that their mutations are suppressed by translational ambiguity. We investigated the effects of mutations near the 5 end of uvsX. A frameshift mutation was engineered at codon 33. Western immunoblots for UvsX protein demonstrated that the frameshift mutant expresses no detectable wild-type UvsX; instead, a 37 kDa reactive peptide was detected. In order to determine if this peptide represents truncated UvsX protein, the mutation was regenerated in the cloned uvsX gene and expressed in transformed Escherichia coli. Endopeptidase digestion of the 37 kDa protein from the cloned gene generated peptide fragments indistinguishable from those obtained from wild-type UvsX. A double-amber mutant of uvsX was also generated by oligonucleotide site-directed mutagenesis. No UvsX protein was detected in lysates of cells infected with the uvsX-am64am67 double mutant. Plaque size and sensitivity to UV inactivation for both the double-amber and the frame-shift mutants were indistinguishable from those of other uvsX mutants. Mutations in uvsY had no demonstrable effect on efficiency of plating or UV sensitivity of uvsX mutants. Thus, null mutants of uvsX are viable.     

鲍曼不动杆菌裂解性噬菌体LZ35的分离及全基因组分析

目的 通过分离鉴定鲍曼不动杆菌噬菌体并进行遗传信息分析,为今后噬菌体用于治疗鲍曼不动杆菌引起的感染提供依据。方法 以鲍曼不动杆菌临床分离株为宿主菌,从医院污水中分离鲍曼不动杆菌噬菌体并进行纯化、电镜观察形态特征、提取噬菌体DNA,进行全基因组测序,分析全基因组的结构特征,比较基因组分析其进化关系。结果 分离到鲍曼不动杆菌裂解性噬菌体LZ35,电镜观察显示,该噬菌体属于有尾噬菌体目肌尾病毒科。基因组全长44 885 bp,G＋C含量为37.95%,含有83个开放阅读框,其中22个编码序列可预测其功能,61个编码序列为未知基因。噬菌体LZ35的基因组与鲍曼不动杆菌噬菌体IME-AB2和YMC-13-01-C62具有很高的同源性（分别为97%和99%）,与鲍曼不动杆菌噬菌体YMC11/12/R1215的进化关系最近。结论 以鲍曼不动杆菌临床分离株为宿主菌,分离到鲍曼不动杆菌裂解性噬菌体LZ35,明确了其形态和基因组特征,为防治噬菌体疗法奠定基础。     

Lymphatic function and responses in periodontal disease

Extravasated fluid, proteins and cells are returned into the circulation by lymphatic vessels that are also important in immune cell trafficking. Lymphatic vessels in gingiva are located in lamina propria, and traverse the external surface of the alveolar bone. Lack of gingival lymphatics has been shown to increase the interstitial fluid pressure and fluid volume, thus showing that lymphatics are important for fluid drainage also in this tissue. Gingival lymphatic vessels require continuous signaling by the growth factors VEGF-C and D via their receptor VEGFR-3 for their maintenance, factors that are expressed in the gingival epithelium and also in immune cells in lamina propria. VEGF-C seems to be of critical importance for lymphangiogeneses induced during periodontal disease development. Mice are protected against periodontitis by lymphatics clearing bacteria and bacterial products and promoting humoral immune responses. CCL21, a ligand important for dendritic cell migration, has been found to be downregulated in lymphatics from patients with periodontitis. Such patients may have impaired gingival lymphatic function due to high enzymatic activity and thus loss of structural components in the interstitium. At present there are few studies on the role of lymphatic vessels in periodontal disease making this a rather unexplored field.     

环境胁迫和非胁迫条件下类植物乳杆菌转录组分析

【背景】类植物乳杆菌L-ZS9是一株在食品发酵与保鲜方面具有潜在应用价值的产细菌素益生菌。【目的】深入了解环境胁迫影响类植物乳杆菌L-ZS9细菌素合成的重要相关调节基因的信息。【方法】通过高通量测序技术对类植物乳杆菌转录组进行测序,对所有转录本进行COG(Clusters of Orthologous Groups)、GO(Gene Ontology)和KEGG(Kyoto Encyclopedia of Genes and Genomes)分类和Pathway注释。【结果】转录组测序显示2个样品基因覆盖度都在90%以上,差异表达基因927个,其中744个上调,183个下调。KEGG分析结果表明,649个差异表达基因中68个集中在"ABC转运途径",占10.48%,其中3个基因表达上调超过16倍,1个基因表达下调超过1/16,暗示类植物乳杆菌L-ZS9细菌素合成与"ABC转运途径"密切相关。另外多个孤儿基因表达变化也超过16倍,有的甚至表达上调达万倍。【结论】进一步拓展了类植物乳杆菌的基因信息,为类植物乳杆菌细菌素代谢途径和逆境反应研究提供了坚实的基础。     

Structure of factor H-binding protein B (FhbB) of the periopathogen, Treponema denticola: insights into progression of periodontal disease

Periodontitis is the most common disease of microbial etiology in humans. Periopathogen survival is dependent upon evasion of complement-mediated destruction. Treponema denticola, an important contributor to periodontitis, evades killing by the alternative complement cascade by binding factor H (FH) to its surface. Bound FH is rapidly cleaved by the T. denticola protease, dentilisin. In this report, the structure of the T. denticola FH-binding protein, FhbB, was solved to 1.7 Å resolution. FhbB possesses a unique fold that imparts high thermostability. The kinetics of the FH/FhbB interaction were assessed using surface plasmon resonance. A K_D value in the micromolar range (low affinity) was demonstrated, and rapid off kinetics were observed. Site-directed mutagenesis and sucrose octasulfate competition assays collectively indicate that the negatively charged face of FhbB binds within FH complement control protein module 7. This study provides significant new insight into the molecular basis of FH/FhbB interaction and advances our understanding of the role that T. denticola plays in the development and progression of periodontal disease.