Peripheral blood leukocyte telomere length is associated with age but not renal function: A cross-sectional follow-up study

Objectives

We aimed to evaluate the relationship between baseline renal function and changes in telomere length in Han Chinese.

Methods

The telomere restriction fragment (TRF) length of leukocytes in the peripheral blood was measured in healthy volunteers recruited in 2014. The estimated glomerular filtration rate (eGFR) was calculated based on serum creatinine (Scr) and serum cystatin C (CysC)-eGFRcys and eGFRScr-cys through the Cockcroft-Gault formula (eGFRC-G) or the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI / eGFRCKD-EPI) equation. The correlation between telomere length changes over time and renal function was analyzed.

Results

Leukocyte TRF lengths were negatively correlated to age (r = -0.393, p < 0.001) and serum CysC (r = -0.180, p < 0.01), while positively associated with eGFRCKD-EPI, eGFRC-G, eGFRcys, and eGFRScr-cys (r = 0.182, 0.122, 0.290, and 0.254 respectively, p < 0.01). The 3-year change of telomere length was 46 bp/years. When adjusted for age, the associations between telomere length changes and baseline, subsequent TRF lengths, and serum CysC were no longer present. No association was observed between TRF length changes and renal function.

Conclusion

The rate of telomere length changes was affected by age and baseline telomere length. The telomere length changes might be important markers for aging.

     

Effect of Dibutyl Phthalate on the Tolerance and Lipid Accumulation in the Green Microalgae <Emphasis Type="Italic">Chlorella vulgaris</Emphasis>

Offshore oil exploration creates threats to coastal ecosystems, including increasing urbanization and associated effluent releases. Genotoxicity biomarkers in mussels were determined across a gradient of coastal zone influences of offshore petroleum exploration in southeastern Brazil. Coastal ecosystems such as estuaries, beaches and islands were seasonally monitored for genotoxicity evaluation using the brown mussel Perna perna. The greatest DNA damage (5.2%?±?1.9% tail DNA and 1.5‰? ±?0.8‰ MN) were observed in urban estuaries, while Santana Archipelago showed levels of genotoxicity near zero and is considered a reference site. Mussels from urban and pristine beaches showed intermediate damage levels, but were also influenced by urbanization. Thus, mussel genotoxicity biomarkers greatly indicated the proposed oil exploration and urbanization scenarios that consequently are genetically affecting coastal organisms.     

Follicular gastritis associated with Helicobacter pylori

In order to understand the pathogenesis of gastric lymphoma, we investigated the association of H.pylori infection with lymphoid follicular hyperplasia. Eighty-four gastric specimens removed for gastroduodenal ulcer were histologically examined. The distribution and prevalence of H. pylori, neutrophilic and lymphocytic infiltration, mucosal atrophy, intestinal metaplasia, and lymphoid follicles were scored. The lymphoid follicles were more frequently observed in H.pylori positive cases. They indicated a positive correlation with the score of H. pylori. When follicular gastritis (FG) was defined as a case in which the secondary lymphoid follicles (Lf2) numbered two or more per one centimeter of mucosa in the pyloric gland area of the lesser curvature, twenty specimens out of the 84 (24%) fit that definition. All of the FG cases were H.pylori positive, and they displayed high H. pylori scores. It was supposed that most FG cases would ultimately lead to atrophic gastritis, whereas H.pylori would gradationally decrease or disappear in accordance with the aging and progression of intestinal metaplasia. The histological features of the FG cases, however, were similar to the background mucosal state of early-stage MALT-type gastric lymphoma. We may conclude that H. pylori infection is one cause of the FG, which may be a high-risk condition that gives rise to MALT-type gastric lymphoma.     

Platelet-derived growth factor-B gene delivery sustains gingival fibroblast signal transduction

Background and Objective: Platelet‐derived growth factor‐BB is a potent mediator of tooth‐supporting periodontal tissue repair and regeneration. A limitation of the effects of topical platelet‐derived growth factor‐BB application is its short half‐life in vivo. Gene therapy has shown strong promise for the long‐term delivery of platelet‐derived growth factor in both skin ulcer healing and periodontal tissue engineering. However, little is known regarding the extended effects of platelet‐derived growth factor‐B on cell signaling via gene delivery, especially at the level of phosphorylation of intracellular kinases. This study sought to evaluate the effect of gene transfer by Ad‐PDGF‐B on human gingival fibroblasts (HGFs) and the subsequent regulation of genes and cell‐surface proteins associated with cellular signaling. Material and Methods: HGFs from human subjects were treated by adenoviral PDGF‐B, PDGF‐1308 (a dominant negative mutant of PDGF) and recombinant human platelet‐derived growth factor‐BB, and then incubated in serum‐free conditions for various time points and harvested at 1, 6, 12, 24, 48, 72 and 96 h. Exogenous PDGF‐B was measured by RT‐PCR and Western blot. Cell proliferation was evaluated by [methyl‐³H]thymidine incorporation assay. We used proteomic arrays to explore phosphorylation patterns of 23 different intracellular kinases after PDGF‐B gene transfer. The expression of α and β PDGFR and Akt were measured by Western blot analysis. Results: Sustained in vitro expression of PDGF‐B in HGFs by Ad‐PDGF‐B transduction was seen at both the mRNA and protein levels. Compared to rhPDGF‐BB and Ad‐PDGF‐1308, Ad‐PDGF‐B maintained cell growth in serum‐free conditions, with robust increases in DNA synthesis. Gene delivery of PDGF‐B also prolonged downregulation of the growth arrest specific gene (gas) PDGFαR. Of the 23 intracellular kinases that we tested in proteomic arrays, Akt revealed the most notable long‐term cell signaling effect as a result of the over‐expression of Ad‐PDGF‐B, compared with pulse recombinant human platelet‐derived growth factor BB. Prolonged Akt phosphorylation was induced by treatment with Ad‐PDGF‐B, for at least up to 96 h. Conclusion: These findings further demonstrate that gene delivery of PDGF‐B displays sustained signal transduction effects in human gingival fibroblasts that are higher than those conveyed by treatment with recombinant human platelet‐derived growth factor‐BB protein. These data on platelet‐derived growth factor gene delivery contribute to an improved understanding of these pathways that are likely to play a role in the control of clinical outcomes of periodontal regenerative therapy.     

Odontiatrogenic tooth fracture

While the awareness of vertical tooth fractures, whether incomplete or complete, is increasing, sufficient attention has not been paid to the manner in which the dentist may contribute to the occurrence of these fractures. This paper focuses on the most likely areas in which the practitioner can either misdiagnose the presence of a fractured tooth or where dental procedures contribute to fracture of the tooth structure. For this type of fracture the authors propose the term 'odontiatrogenic tooth fracture'.     

常用根管充填材料生物相容性研究

通过细胞附着实验和扫描电镜技术对四种常用根管封闭剂以及三种牙胶尖的生物相容性研究发现：所有充填材料甚至一直被 认为细胞毒性最小的牙胶尖均有明显的细胞毒性。因此，在临床上，为了避免材料对根尖周细胞产生机械刺激和减少细胞毒性作用，应尽量避免根管充填材料超填。本文还就氯仿是否可用于根管治疗进行了讨论。     

Validation of DIAGNOdent for quantification of smooth-surface caries: an in vitro study

The aims were 1) to validate a laser-based device, KaVo DIAGNOdent, for quantification of caries lesions on smooth surfaces, using histopathologic and microradiographic analyses as the gold standard, and 2) to test inter- and intra-observer agreements. We also investigated the influence on DIAGNOdent readings of the storage medium used for extracted teeth. Two observers measured independently the tooth surfaces of 40 extracted premolars that had been stored in thymol-saturated saline. After subsequent storage in neutral-buffered formalin for 14 days they were re-measured. The teeth were then sectioned for histopathologic and microradiographic analysis. The Spearman rank correlation coefficients between lesion depth and DIAGNOdent readings were 0.78-0.83 and 0.85 for teeth stored in thymol-saturated saline and formalin, respectively. Inter- and intra-observer agreements were 0.94 and 0.95 when the teeth were stored in thymol-saturated saline. The DIAGNOdent reading was almost 1.5 times higher for teeth stored in formalin than for those stored in thymol saline. The Spearman rank correlation coefficient between mineral loss in enamel (deltaZ) and DIAGNOdent readings ranged from 0.64 to 0.68. It was concluded that DIAGNOdent may be helpful for assessing smooth-surface caries, but the cut-off points need to be assessed under clinical conditions. The increase in fluorescence associated with storage of teeth in formalin warrants further investigation.     

Human ameloblastoma tumors express the amelogenin gene.

Instructive signals are responsible for the regulation of the expression of gene products characteristic of many cell lineages during normal development and potentially during neoplasia. The odontogenic origin of ameloblastomas is based largely on the similarity in histologic appearance between the tumor and the developing tooth organ. A pathognomonic pattern for odontogenic tissue-specific gene expression in ameloblastomas has not been previously shown. In these studies, the gene expression parameters for human ameloblastomas have been characterized with the techniques of messenger RNA phenotyping in combination with Northern and in situ hybridization analysis of messenger RNA. The results of these studies confirm that amelogenin, a gene transcribed solely by differentiated ameloblasts, was expressed by epithelial cells from human ameloblastomas. This observation suggests that the instructive signals required for ameloblast differentiation are shared during normal development and tumorigenesis of odontogenic epithelium.     

免疫化疗与TIUL得率及其杀瘤活性测定

Tumor-infiltrating lymphocyte (TIL) in the primary site of oral SCC treated with S-PVP of PVP therapy was collected respectively and its yield,that is calculating the amount of TIL per tumor tissue.The cytotoxicity of TIL against the target,Tca8113 was detected.The results showed that the yield of TIL in S-PVP group was three times over that in PVP group.At the ratio of 5 to 1 (effector to target) the cytotoxicity was 38% in S-PVP group and 32% in PVP group.There was no significant difference in its cytotoxicity between two groups.The results revealed that immunochemotherapy of S-PVP regimen for treating oral SCC had neither direct damage to tumor cell from the agents nor antitumor immune reactivity with BRM stimulating an increasing in numbers of TIL.