[Porphyromonas gingivalis outer membrane vesicles activate Toll-like receptor 2 to promote osteoclast differentiation by carrying lipopolysaccharide].

Objective: To investigate the effects of Porphyromonas gingivalis derived outer membrane vesicles (Pg OMV) on osteoclast differentiation of macrophages and its underlying mechanisms. Methods: The morphology and the size distribution of Pg OMV were analyzed by transmission electron microscopy and nanoparticle tracing analysis, respectively. The osteoclast precursors were treated with 1, 3 and 10 mg/L Pg OMV (1, 3 and 10 mg/L OMV treatment group) or phosphate buffer solution (PBS)(control group). The formation of osteoclasts was analyzed by tartrate-resistant acid phosphase (TRAP) staining and F-actin staining and real-time quantitative PCR (RT-qPCR) were used to detect the expression of Fos and matrix metallopeptidase 9 (MMP9). Polymyxin B (PMB) was used to block lipopolysaccharide (LPS) and then Pg OMV was used to treat osteoclast precursor (PMB-OMV treatment group), and OMV treatment group was used as control. TRAP and F-actin staining were used to observe the formation of osteoclasts and actin rings. The effect of Pg OMV on the expression of Toll-like receptor (TLR) 2 and TLR4 in preosteoclasts was detected by Western blotting. The osteoclast precursors were pretreated with 10, 50, 100 and 200 µmol/L C29, an inhibitor of TLR2, and then treated with Pg OMV(OMV+10, 50, 100 and 200 µmol/L C29 treatment group) and OMV treatment group without C29 pretreatment was control. TRAP and F-actin staining were used to observe the formation of osteoclasts and actin rings. The osteoclast precursor cells were treated with OMV (OMV treatment group) and OMV incubated with PMB (PMB-OMV treatment group) and the expression of TLR2 in osteoclast precursor was detected by Western blotting. Results: Pg OMV showed classical vesicular structures, and the average particle size of Pg OMV were 179.2 nm. A large number of actin rings were observed in the 3 and 10 mg/L OMV treatment groups. The percentages of TRAP-positive osteoclast area in 3 mg/L OMV treatment group [(22.6±2.1)%] and 10 mg/L OMV treatment group [(32.0±2.3)%] were significantly increased compared with control group [(4.9±0.5)%] (P<0.001). Compared with the control group (1.000±0.029), the mRNA relative expression of Fos in 3 mg/L OMV treatment group (1.491±0.114) and 10 mg/L OMV treatment group (1.726±0.254) was significantly increased (P=0.013, P=0.001). Compared with the control group (1.007±0.148), the mRNA relative expression of MMP9 in the group of 10 mg/L OMV (2.232±0.097) was significantly increased (P<0.001). Actin ring formation was less in PMB-OMV treatment groups than in OMV treatment groups. The proportion of TRAP-positive osteoclasts area [(14.8±3.8)%] in PMB-OMV treatment group was significantly lower than OMV treatment group [(31.5±6.7) %] (P=0.004). The relative expression of TLR2 in OMV treatment group (1.359±0.134) was significantly higher than that in the control group (1.000±0.000) (t=4.62, P=0.044). Compared with the OMV treatment group [(29.4±1.7)%], 50, 100 and 200 µmol/L C29 significantly decreased the formation of osteoclasts [(24.0±1.7)%, (18.5±2.1)%, (9.1±1.3) %] (P=0.026, P<0.001, P<0.001). TLR2 protein expression in PMB-OMV group (0.780±0.046) was significantly lower than that in OMV group (1.000±0.000)(t=8.32, P=0.001). Conclusions: Pg OMV can promote osteoclast differentiation by carrying LPS, TLR2 plays an important role in Pg OMV mediated osteoclast differentiation.

[Long non-coding RNA LINC01133 regulates cementogenic differentiation of human periodontal ligament stem cells by modulating mitochondrial functions].

Objective: To investigate the effects of long non-coding RNA (lncRNA) LINC01133 on the cementogenic differentiation of human periodontal ligament stem cells (hPDLSC) and the underlying mechanism. Methods: A total of 12 teeth were harvested from 10 patients aged 17-30 years in the Department of Oral and Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University for impacted or orthodontic reasons from September 2021 to January 2022. The hPDLSCs were isolated from the teeth and transfected with small interfering RNA-LINC01133 (si-LINC01133) or small interfering RNA-negative control (si-NC). The si-LINC01133 was regarded as the experimental group, and the si-NC was regarded as the control one. The silencing efficiency of LINC01133 in the hPDLSCs was evaluated by real-time quantitative PCR (RT-qPCR). Western blotting was used to detect the protein expression levels of cementogenic differentiation-related factors including bone sialoprotein (BSP), cementum attachment protein (CAP), and cementum protein-1 (CEMP-1). Mitochondrial reactive oxygen species (mtROS) production was assessed using the MitoSox by flow cytometry. Mitochondrial membrane potential (MMP) was detected by JC-1 fluorescence staining. Mitochondrial respiratory chain complexes proteins including NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 8 (NDUFB8), succinate dehydrogenase complex flavoprotein subunit A (SDHA), ubiquinol-cytochrome c reductase core protein 1 (UQCR1), cytochrome c oxidase subunit 4 isoform 1 (COXⅣ), and ATP synthase F1 subunit alpha (ATP5A) were evaluated by Western blotting. Results: The expression levels of LINC01133 could be suppressed by more than 60% with si-LINC01133 (control group: 1.000±0.000, experimental group: 0.385±0.128) (t=10.72, P<0.01). Suppression of LINC01133 in hPDLSCs decreased the levels of cementogenic differentiation-related proteins including BSP (control group: 1.000±0.000, experimental group: 0.664±0.179) (t=4.62, P<0.01) and CAP (control group: 1.000±0.000, experimental group: 0.736±0.229) (t=2.83, P<0.05). Suppression of LINC01133 in hPDLSCs increased the production of mtROS (control group: 1.000±0.000, experimental group: 1.458±0.185) (t=4.96, P<0.05) and the expression of NDUFB8 (control group: 1.000±0.000, experimental group: 1.683±0.397) (t=3.45, P<0.05), as well as decreased MMP levels (control group: 1.000±0.000, experimental group: 0.209±0.029) (t=53.99, P<0.01) and the expression of SDHA (control group: 1.000±0.000, experimental group: 0.428±0.228) (t=5.02, P<0.05). No significant changes in the UQCR1, COXⅣ, and ATP5A expression levels were found between the control group and exprimental group (P>0.05). Conclusions: LINC01133 regulates the cementogenic differentiation of hPDLSCs possibly via modulating the mitochondrial functions.

Breakup of the proton halo nucleus 8B near barrier energies.

The dynamics of a nuclear open quantum system could be revealed in the correlations between the breakup fragments of halo nuclei. The breakup mechanism of a proton halo nuclear system is of particular interest as the Coulomb polarization may play an important role, which, however, remains an open question. Here we use a highly efficient silicon detector array and measure the correlations between the breakup fragments of 8B incident on 120Sn at near-barrier energies. The energy and angular correlations can be explained by a fully quantum mechanical method based on the state-of-the-art continuum discretized coupled channel calculations. The results indicate that, compared to the neutron halo nucleus 6He, 8B presents distinctive reaction dynamics: the dominance of the elastic breakup. This breakup occurs mainly via the short-lived continuum states, almost exhausts the 7Be yield, indicating the effect of Coulomb polarization on the proton halo state. The correlation information reveals that the prompt breakup mechanism dominates, occurring predominantly on the outgoing trajectory. We also show that, as a large environment, the continuum of 8B breakup may not significantly influence elastic scattering and complete fusion.

[A Luciferase-EGFP Reporter System for the Evaluation of DNA Methylation in Mammalian Cells].

DNA methylation is an essential epigenetic modification involved in numerous biological processes. Here, we present a cell-based system pLTR-Luc2P-EGFP for evaluation of DNA methylation in mammalian cells. In this system, the expression of reporter gene luciferase2P (Luc2P)-EGFP is under the control of HIV-1 promoter 5' long terminal repeat (LTR), which contains multiple CpG sites. Once these sites are methylated, the expression of Luc2P-EGFP is turned off, which may be visualized under fluorescence microscopy, with quantification performed in luciferase activity assay. As a proof of principle, pLTR-Luc2P-EGFP was methylated in vitro, and transfected into 293T cells, where the reduction of Luc2P-EGFP expression was confirmed. Premixed reporter DNA samples with the methylation levels varying from 0 to 100% were used for quantitative measurements of DNA methylation. The resulting standard curves indicated the accuracy of luciferase activity exceeding that of the Western blotting against EGFP. The Bland-Altman analysis showed that data from luciferase activity assay were in good agreement with the actual DNA methylation levels. In summary, we have established a reporter system coupled with reliable detection technique capable of efficient quantifying the changes in methylation in mammalian cells. This system may be utilized as a high throughput screening tool for identifying molecules that modulate DNA methylation.

[Research on quantitative method and contamination level of Salmonella enterica in raw pork from farmer's markets in Chengdu].

To optimize the quantitative detection method for Salmonella enterica and analyze the quantitative contamination level of Salmonella enterica in raw pork samples from farmer's markets in Chengdu. Based on qualitative detection standard method of Salmonella enterica in China (GB 4789.4-2016) and the quantitative detection method of FSIS in the United States (MLG 4.08 and MLG appendix 2.05 MPN), the selective enrichment broth, screening plate, identification method and quantitative dilution ratio in quantitative detection of Salmonella enterica were optimized using 70 samples of raw pork. The optimized method compared by student's t-test was used to detect 40 samples of raw pork collected from farmer's markets in Chengdu from June to October 2020. For isolation of Salmonella from raw pork samples, the coincidence degree of TTB enrichment solution was significantly higher than that of RV enrichment solution (0.93±0.32 vs 0.35±0.62,t=8.324,P=0.001) and the consistency of suspicious colonies screened by XLT4 plate was significantly higher than that of Salmonella chromogenic medium (0.77±0.09 vs 1.00±0.00,t=2.971,P =0.017). The MPN method used 4 successive gradient dilutions, namely 12 tube method, could obtain more accurate quantitative value for Salmonella enterica. The combined use of selective enrichment broth TTB, XLT4 plate, Real-time PCR and MALDI-TOF mass spectrometry could get better results for screening and identifying Salmonella enterica. The detection rate for Salmonella enterica isolated from raw pork in farmer's markets was 92.5% (37/40). The most of the Salmonella positive samples (83.8%, 31/37) were detected with a contamination level ranged from 0.1 to 55 MPN/g. The optimized quantitative detection method for Salmonella enterica in raw pork in this study can effectively screen the target bacteria and obtain more accurate quantitative value.

A Luciferase-EGFP Reporter System for the Evaluation of DNA Methylation in Mammalian Cells.

DNA methylation is an essential epigenetic modification involved in numerous biological processes. Here, we present a cell-based system pLTR-Luc2P-EGFP for evaluation of DNA methylation in mammalian cells. In this system, the expression of reporter gene luciferase2P (Luc2P)-EGFP is under the control of HIV-1 promoter 5' long terminal repeat (LTR), which contains multiple CpG sites. Once these sites are methylated, the expression of Luc2P-EGFP is turned off, which may be visualized under fluorescence microscopy, with quantification performed in luciferase activity assay. As a proof of principle, pLTR-Luc2P-EGFP was methylated in vitro, and transfected into 293T cells, where the reduction of Luc2P-EGFP expression was confirmed. Premixed reporter DNA samples with the methylation levels varying from 0 to 100% were used for quantitative measurements of DNA methylation. The resulting standard curves indicated the accuracy of luciferase activity exceeding that of the Western blotting against EGFP. The Bland-Altman analysis showed that data from luciferase activity assay were in good agreement with the actual DNA methylation levels. In summary, we have established a reporter system coupled with reliable detection technique capable of efficient quantifying the changes in methylation in mammalian cells. This system may be utilized as a high throughput screening tool for identifying molecules that modulate DNA methylation.

[Clinical analysis of 382 immediately breast reconstruction after mastectomy in Beijing City, Tianjin City and Hebei Province from 2012 to 2016].

Objective: To summarize the status of immediate breast reconstruction (IBR) after mastectomy in Beijing City, Tianjin City and Hebei Province. Methods: A retrospective analysis was made on the data of 382 cases with breast cancer who were treated and followed up successfully with immediate breast reconstruction after mastectomy from January 2012 to December 2016 in Beijing City, Tianjin City and Hebei Province. Clinic data of the followed-up 382 cases (all female, age (38.5±4.2) years (range: 24 to 70 years)), including general information, tumor information, sugery methods, and treatments after surgery were collected. The survival status, metastasis,complications and prognosis were followed up. Cosmetic effcet was evalated by Harris method, and life quality by Functional Assessment of Cancer Therapy-Breast scale (FACT-B). χ(2) test was used to compare the difference between year 2012 and year 2013 to 2016. Bonferroni method was used to correct the inspection level, which was 0.05/10=0.005. The trend of IBR rate (ratio of IBR to modified radical mastectomy) from 2013 to 2016 was analyzed by trend χ(2) test. Results: There was 46 cases in stage 0, 152 cases in stage Ⅰ, 165 cases in stage Ⅱ, 19 cases in stage Ⅲ. Twenty-five cases was treated by neoadjuvant chemotherapy, 231 by chemotherapy and 35 by radiotherapy. The proportion of implant reconstruction was 48.7% (186/382), more than expanded of 21.5% (82/382), with latissimus dorsi of 12.0% (46/382), TRAM of 8.9% (34/382), DIEP of 2.1% (8/382), and latissimus plus implant of 6.8% (26/382). According to the Harris standard, the excellent and good rate of the cosmetic effect of the reconstructed breast was 93.7%. The score of FACT-B was 108.20±16.9 (range: 67 to 144) 1 year postoperatively. Compared with 2012, the IBR rate was significant increased, till 2015, the IBR rate was 153/10 000 cases (χ(2)=47.028, P=0.000). Conclusions: There is a significant increase on IBR rate in Beijing City, Tianjin City and Hebei province by year. Most of cases received IBR is stage Ⅰ to Ⅱ. Implant reconstruction is the main reconstructive method. Postoperative cosmetic effects and quality of life are both meet patients' demon.

[The sex- and age-specific association between resting heart rate and hypertension in rural adult residents of Henan province].

Objective: To investigate the sex- and age-specific association between resting heart rate and hypertension in rural adult residents of Henan province. Methods: At baseline, a total of 20 194 participants were randomly selected from Xin'an County of Henan province between July 2007 and August 2008. After excluding participants with hypertension or without resting heart rate data at baseline, and participants died or without hypertension outcome or diagnosed as gestational hypertension during follow-up between July 2013 and October 2014, 10 212 participants were finally included in this study. Multiple linear regression model was used to examine the association between resting heart rate and change of blood pressure. Logistic regression model was used to estimate the association between resting heart rate and risk of hypertension. Results: There were 2 059 new hypertensive cases (839 male) during the 6 years follow-up. After controlling for potential confounders, per 5 beats/minutes increases in resting heart rate was associated with 0.18 mmHg (1 mmHg=0.133 kPa) (95%CI 0.01-0.36 mmHg, P=0.046) absolute increase in systolic blood pressure and 7% higher risk of developing hypertension in women (95%CI 1.03-1.11, P<0.05). Compared with resting heart rate<70 beats/minutes, the adjusted RRs for 76-82 and>82 beats/minutes groups were 1.39 (95%CI 1.18-1.63, P<0.05) and 1.22 (95%CI 1.02-1.45, P<0.05), respectively. For both age groups, increased resting heart rate was positively associated with risk of hypertension in women(RR=1.05(95% CI 1.01-1.10), P<0.05 (the women those <60 years); RR=1.14(95% CI 1.04-1.25), P<0.05 (the women those≥60 years). However, no significant association was found between resting heart rate and hypertension in male residents. Conclusions: Increased resting heart rate is associated with high risk of hypertension in women who live in rural area, especially in elder women of this cohort.

MicroRNA-378 attenuates myocardial fibrosis by inhibiting MAPK/ERK pathway.

OBJECTIVE: To elucidate the role of microRNA-378-containing microvesicles (MVs) in the process of myocardial fibrosis and its underlying mechanism. MATERIALS AND METHODS: In vivo chronic myocardial fibrosis (MF) model in rats was established by aortic coarctation method. MicroRNA-378 mimic or inhibitor was injected into the rat tail vein at day 3 after the aortic coarctation. Two weeks later, rats were sacrificed for collecting myocardium. MVs were isolated from rat cardiomyocytes and further verified by detecting the expression level of its marker CD63. Expression levels of fibrosis-related indicators and microRNA-378 in MVs were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot. After induction with transforming growth factor-ß1 (TGF-ß1) in primary rat cardiomyocytes for different time points, expression levels of fibrosis-related indicators and microRNA-378 were also accessed. Changes in mitogen-activated protein kinase (MAPK) pathway were observed during the process of MF by qRT-PCR and Western blot. RESULTS: Expression levels of microRNA-378-containing MVs decreased, and the MAPK pathway was activated during the process of MF, which further aggravated MF. CONCLUSIONS: MicroRNA-378-containing MVs alleviate myocardial fibrosis through inhibiting the phosphorylation of MAPK.

MiR-98-5p regulates myocardial differentiation of mesenchymal stem cells by targeting TBX5.

OBJECTIVE: This study aims to investigate whether miR-98-5p can participate in the myocardial differentiation of bone marrow mesenchymal stem cells (MSCs) by regulating TBX5. MATERIALS AND METHODS: In this study, we first identified the MSCs that were isolated from rat bone marrow samples. Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to detect mRNA expressions of cardiac-related genes, including brain natriuretic peptide (BNP), α-actinin, and Islet-1. The binding site of miR-98-5p and TBX5 was detected by dual-luciferase report gene assay. In addition, co-transfection of miR-98-5p mimics and TBX5 overexpression plasmids was conducted to assess whether miR-98-5p could regulate myocardial differentiation by targeting TBX5. RESULTS: Overexpression of TBX5 or knockdown of miR-98-5p promoted myocardial differentiation of BMSCs. The mRNA expressions of α-actinin and Islet-1 were significantly increased after the miR-98-5p knockdown. Dual-luciferase report gene assay showed that miR-98-5p could bind to TBX5, which was further verified by qRT-PCR. Additionally, TBX5 overexpression reversed the inhibitory effect of miR-98-5p on regulating the mRNA expressions of α-actinin and Islet-1. CONCLUSIONS: MiR-98-5p can inhibit the differentiation of rat MSCs into cardiomyocytes through targeting TBX5.

Leveraging Stem Cell Homing for Therapeutic Regeneration.

Resident stem cell pools in many tissues/organs are responsible not only for tissue maintenance during physiologic turnover but also for the process of wound repair following injury. With inspiration from stem cell trafficking within the body under physiologic and pathologic conditions, recent advances have been made toward inducing stem cell mobilization and directing patients' own cells to sites of interest for treating a broad spectrum of diseases. An evolving body of work corroborates that delivering guidance cues can mobilize stem cells from the bone marrow and drive these cells toward a specific region. In addition, the transplantation of cell-friendly biomaterials incorporating certain biomolecules has led to the regeneration of lost/damaged tissue without the need for delivering cellular materials manipulated ex vivo. Recently, cell homing has resulted in remarkable biological discoveries in the laboratory as well as great curative successes in preclinical scenarios. Here, we review the biological evidence underlying in vivo cell mobilization and homing with the aim of leveraging endogenous reparative cells for therapeutic applications. Considering both the promise and the obstacles of this approach, we discuss how matrix components of the in vivo milieu can be modified to promote the native regenerative process and inspire future tissue-engineering design.

[Changes and implications of esophageal function in patients with chronic cough induced by gastroesophageal reflux].

Objective: To explore the changes in the esophageal function and their association with the therapeutic outcome in patients with gastroesophageal reflux-induced chronic cough (GERC). Methods: One hundred thirty-five patients with definite GERC consecutively referred to our respiratory clinic were recruited into the study between January 2012 and August 2015.Cough was due to acid reflux in 81 patients and non-acid reflux in 54 patients, with the favorable response to the standard antireflux therapy in 88 patients and to the intensified antireflux treatment in 47 patients. The control groups included 26 patients with gastroesphageal reflux disease without cough and 22 healthy volunteers. All the subjects underwent an esophageal manometry from which the parameters were recorded, including the pressure, length and relaxation rate of lower esophageal sphincter, and the peristaltic contractive amplitude, wave velocity and contractive time of esophagus. The data were combined with the results of multi-channel intraluminal impedance combined with pH monitoring to analyze the changes of esophageal function in the patients with acid or non-acid GERC and their relation to the outcomes of antireflux therapy. Results: Compared with healthy volunteers, patients with GERC presented with a lower pressure [(11±5) mmHg vs (15±5) mmHg (1 mmHg=0.133 kPa), q=3.70, P=0.000], shorter overall length [(2.2±0.5) cm vs (3.0±1.0) cm, q=2.78, P=0.017] and similar relaxation rate of lower esophageal sphincter(q=1.14, P=0.258). Furthermore, they also showed a decrease in esophageal peristaltic contractive amplitude [(33±13) mmHg vs (45±11) mmHg, q=2.19, P=0.030] and wave velocity [(2.6±0.8) cm/s vs (3.4±0.6) cm/s, q=2.91, P=0.010] but an increase in esophageal contractive time of esophagus [(4.9±2.2) s vs (3.1±0.8) s, q=3.25, P=0.001] in addition to a linear negative correlation between esophageal peristaltic wave velocity and bolus clearance (r=-0.603, P=0.000). However, these parameters were not different between patients with GERC and gastroesophageal reflux disease without cough. The patients with GERC due to acid and non-acid reflux presented with a similar esophageal dysmotility but different variables reflecting the acidity of refluxates as indicated by multi-channel intraluminal impedance combined with pH monitoring. The esophageal peristaltic wave velocity was significantly lower in the patients with GERC responsive to the standard antireflux therapy than in those responsive to the intensified antireflux therapy [(2.2±0.6) cm/s vs (3.0±1.0) cm/s, t= 2.066, P= 0.041]. Conclusions: Esophageal dysfunction is present in patients with GERC. Its characteristics and severity are not associated with the types of gastroesophageal reflux inducing cough, but may predict the efficacy of medical antireflux therapy.

Meta-analysis of TAFI polymorphisms and risk of cardiovascular and cerebrovascular diseases.

Cardiovascular and cerebrovascular diseases (CCVDs) are common and have high rates of morbidity, mortality, and recurrence. Thrombin-activatable fibrinolysis inhibitor (TAFI) is also known as carboxypeptidase B2 and is encoded by the CPB2 gene; CPB2 polymorphisms have been explored in a variety of studies, but their correlation to the risk of CCVDs remains ambiguous. We examined the hypothesized associations between CPB2 mutations and CCVDs in a general population. We searched, Embase, the Cumulative Index to Nursing and Allied Health Literature, the Science Citation Index, and several Chinese databases without applying any language restrictions. Nine case-control studies were analyzed in the current meta-analysis, and odds ratios (ORs) with their 95% confidence intervals were calculated. The pooled ORs indicated that the CPB2 rs3742264 G>A polymorphism was associated with an increased risk of CCVDs in the allele model (all P values < 0.05). A similar result for the CPB2 rs1926447 C>T polymorphism and CCVDs risk was detected in the allele model (P < 0.05). Ethnicity subgroup analysis implied that the rs3742264 G>A polymorphism was more likely to lead to the development of cerebrovascular disease in Asians (all P values < 0.05), whereas rs1926447 C>T was associated with cardiovascular disease among Africans (all P values < 0.05). These data suggest that the polymorphisms investigated, especially rs3742264 G>A and rs1926447 C>T, have a modest effect on susceptibility to CCVDs.

Mir-509-5p joins the Mdm2/p53 feedback loop and regulates cancer cell growth.

Although the Mdm2/p53 interaction has been well documented, it is not clear whether there are new microRNAs participating in this regulatory network. Here, we provide evidence that miR-509-5p, which is downregulated in a subset of newly diagnosed cervical cancer and hepatocellular carcinoma tissues compared with the adjacent nontumor tissue, can be activated by p53 through binding the promoter of miR-509-5p and it suppresses the growth and invasion/migration of cervical cancer and hepatoma cells by regulating apoptosis and the G1/S-phase transition of cell cycle. Furthermore, Mdm2 was identified to be a target of miR-509-5p by targeting its 3'-UTR. Restoration of Mdm2 abrogated the cell phenotypes induced by miR-509-5p. Moreover, ectopic expression of miR-509-5p in HeLa and QGY-7703 cells repressed the expression of Mdm2, subsequently enhancing its p53-activating effects. These results suggest that miR-509-5p is a new regulator of Mdm2/p53 pathway and may play a key role in cancer development.

Clinical tools do not predict pathological complete response in patients with esophageal squamous cell cancer treated with definitive chemoradiotherapy.

Chemoradiotherapy for locally advanced esophageal squamous cell carcinoma is associated with high rates of pathological complete response. A pathological complete response is recognized to be an important predictor of improved survival, to the extent that observation rather than surgery is advocated by some in patients with presumed pathological complete response based on their clinical response. The goal of this study was to look at the ability of clinical variables to predict pathological complete response after chemoradiotherapy for locally advanced esophageal squamous cell carcinoma. We reviewed retrospectively patients with locally advanced esophageal squamous cell carcinoma who underwent chemoradiotherapy followed by surgery and compared those with pathological complete response to patients with residual disease. Between January 1996 and December 2010, 116 patients met inclusion criteria. Fifty-six percent of patients had a pathological complete response and a median survival of 128.1 months versus 28.4 months in patients with residual disease. When compared with patients with residual disease, patients with a pathological complete response had a lower post-neoadjuvant positron emission tomography (PET) maximum standardized uptake value (SUVmax), a larger decrease in PET SUVmax, a less thick tumor on post-chemoradiotherapy computed tomography and a higher rate of normal appearing post-chemoradiotherapy endoscopy with benign biopsy of the tumor bed. However, none of these characteristics alone was able to correctly identify patients with a pathological complete response, and none has significant specificity. Although the rate of pathological complete response after chemoradiotherapy is high in patients with esophageal squamous cell carcinoma, the ability of identifying patients with pathological complete response is limited. A reduction of the PET SUVmax by >70%, a normal appearing endoscopic examination, and no residual disease on biopsy all were seen in >65% of the patients with a pathological complete response. Even if these findings were unable to confirm the absence of residual disease in the primary tumor, they can help guide expectant management in high-risk patients.

Geldanamycin accelerated peripheral nerve regeneration in comparison to FK-506 in vivo.

FK-506 accelerates nerve regeneration and improves functional recovery in vivo; its immunosuppressive properties, however, limit its clinical utility. Geldanamycin (GA), a non-immunosuppressive agent, shares a common binding target (heat shock protein 90) with FK-506 and may accelerate nerve regeneration through a similar mechanism. GA has been shown to augment neurite outgrowth in vitro but has not been tested in vivo. The current study investigated the effect of GA on the rate of axonal regeneration and functional recovery following peripheral nerve injury. In the first experiment, Thy1-GFP transgenic rats underwent serial transmuscular imaging to quantify the rate of axonal regeneration following saphenous nerve crush injury. In subsequent experiments, Lewis rats underwent tibial nerve crush or transection-and-repair injuries and were assessed for functional recovery by walking track analysis. All animals were randomized to receive daily administration of FK-506 (2mg/kg), GA (0.2mg/kg), or a control vehicle (dimethyl sulfoxide, 1 mL/kg) starting 3 days prior to injury. Both GA and FK-506 significantly increased the rate of axonal regeneration following crush injury in Thy1-GFP rats. In Lewis rats undergoing tibial nerve crush injury, earlier functional recovery occurred at day 5 and day 6 in animals treated with FK-506 and GA respectively, vs. day 13 for controls. Over a truncated 21-day timeframe, Lewis rats undergoing tibial nerve transection-and-repair injury and treated with FK-506 regained function at day 16, whereas those treated with GA or the control vehicle did not regain normal function. GA-treated animals, however, did exhibit significant functional improvement vs. controls. The current study demonstrated that GA accelerates axonal regeneration and enhances functional recovery in vivo. Its ability to increase the rate at which peripheral axons regenerate is comparable to that of FK-506. GA, however, did not match the performance of FK-506 in injury models where Wallerian degeneration (WD) is ongoing in the distal stump. This provides evidence that FK-506 accelerates axonal regeneration through two parallel mechanisms: the first being its well-established effect on neurons; the second is likely a newly described, as-yet poorly defined mechanism that affects WD. Finally, given the decrease in observed toxicity with GA administration, it might be a suitable non-immunosuppressive alternative to FK-506 for accelerating peripheral nerve regeneration in cases of clinical nerve injury.

Double edge: CDK2AP1 in cell-cycle regulation and epigenetic regulation.

Cancer research has been devoted toward an understanding of the molecular regulation and functional significance of cell-cycle regulators in the pathogenesis and development of cancers. Cyclin-dependent Kinase 2-associated Protein 1 (CDK2AP1) is one such cell-cycle regulator, originally identified as a growth suppressor and a prognostic marker for human oral/head and neck cancers. Functional importance and the molecular mechanism of CDK2AP1-mediated cell-cycle regulation have been documented over the years. Recent progress has shown that CDK2AP1 is a competency factor in embryonic stem cell differentiation. Deletion of CDK2AP1 leads to early embryonic lethality, potentially through altered differentiation capability of embryonic stem cells. More intriguingly, CDK2AP1 exerts its effect on stem cell maintenance/differentiation through epigenetic regulation. Cancer cells and stem cells share common cellular characteristics, most prominently in maintaining high proliferative potential through an unconventional cell-cycle regulatory mechanism. Cross-talk between cellular processes and molecular signaling pathways is frequent in any biological system. Currently, it remains largely elusive how cell-cycle regulation is mechanistically linked to epigenetic control. Understanding the molecular mechanism underlying CDK2AP1-mediated cell-cycle regulation and epigenetic control will set an example for establishing a novel and effective molecular link between these two important regulatory mechanisms.

Accuracy of CT-guided biopsies in 158 patients with thoracic spinal lesions.

BACKGROUND: Inconsistent accuracies of CT-guided thoracic spinal biopsies have been reported in previous studies. PURPOSE: To determine the accuracy of CT-guided thoracic spinal biopsy, to compare the results with those previously reported, and to determine if there are any factors that influence the accuracy of CT-guided thoracic spinal biopsy. MATERIAL AND METHODS: In total, 158 consecutive CT-guided percutaneous thoracic spine procedures (performed at the Department of Spinal Surgery, Xi'an Red Cross Hospital between April 2000 and July 2010) were reviewed. The 158 lesions were categorized by location and radiographic features. Pathological and clinical follow-up were used to determine accuracy. RESULTS: The diagnostic accuracy of CT-guided thoracic spinal biopsy was 90.5% overall. Biopsy of metastatic bone disease (98.2%) was significantly more accurate than biopsies of primary tumors (80.9%) and of hematological malignancies (47.0%) (P < 0.05 and P < 0.005, respectively). The diagnostic accuracy of CT-guided thoracic spinal biopsy was significantly higher for the lower thoracic spine (97.6%) than for the middle (90.0%) or upper thoracic spine (80.4%) (P < 0.05 and P < 0.025, respectively). The diagnostic accuracy was significantly higher for lytic lesions (96.4%) than for sclerotic lesions (81.3%) (P < 0.010). The accuracy of biopsies performed using the transpedicular approach (91.0%) was not significantly different from that of biopsies performed using posterolateral approaches (91.5%) (0.25 < P < 0.5). CONCLUSION: Percutaneous CT-guided thoracic spinal biopsy is a viable alternative to open surgical biopsy. The diagnostic accuracy was not affected by any of the variables except for lesion level, histology, and radiographic features.

Time-frequency methods for detecting spike activity of stomach.

It has been hypothesised by many researchers that the spike activity signals of the stomach are responsible for triggering peristaltic contractions. Since most gastric motility disorders include an abnormality in the contraction pattern, it is very important to access this information non-invasively. The aim in this study is to use abdominal electrogastrogram (EGG) signals to detect the spike activity signals generated by the serosa of the stomach, and hence provide clinicians with a better method to monitor the motility state of the stomach. Through second and third-order spectral estimations performed on the serosal data obtained from canine experiments, it was concluded that the spike activity in serosal signals occupies a frequency range of 50-80 cycles per minute. An increase in this frequency range during strong antral contractions was observed both in the serosal and cutaneous power spectra. By using the 'continuous wavelet transform' with respect to a modified Morlet wavelet, the spike activity signals generated from the serosa of the stomach can be detected and quantified in time from the cutaneous EGG records. During phase III contraction episodes, a detection accuracy of up to 96% from the cutaneous EGG recordings was calculated based on the scored serosal spike activities simultaneously recorded.

Enhanced responsiveness to photodynamic therapy-induced apoptosis after mitochondrial DNA depletion.

Several lines of evidence indicate that mitochondria are an especially sensitive target for photodamage. Reports of cross resistance between photodynamic therapy (PDT) and the drug cisplatin, along with evidence that depletion of mitochondrial DNA (mtDNA) sensitized cells to cisplatin suggested a study of the photodynamic responsiveness of murine leukemia control L1210 cells versus cells depleted of mtDNA. Loss of mtDNA led to an increased sensitivity to mitochondrial photodamage, while the cytotoxic effects of lysosomal photodamage were not affected. Cells depleted of mtDNA showed an enhanced apoptotic response to PDT involving a mitochondrial target, compared with control cells.