[Investigation on Demodex infections among university students in Kunming City]

OBJECTIVE

To investigate the prevalence of Demodex infection among students in Kunming Medical University, and identify the factors affecting Demodex infections, so as to provide the evidence for the development of the strategy for the prevention of Demodex infections.

METHODS

A total of 1 463 students from Grade 2014 who studied Medical Parasitology in Kunming Medical University were included in the survey. Demodex was examined in students'facial skin using the cellophane tape method, and the species was identified using microscopy. The students'gender, ethnicity, place of origin and skin type were captured using a questionnaire survey.

RESULTS

The overall prevalence of Demodex infections was 19.07% (279/1 463) on the facial skin among the university students, and a higher prevalence was seen in girls (21.16%, 183/865) than in boys (16.05%, 96/598) (χ² =5.965,P <0.05).TheprevalenceofDemodex infectionswas18.33%(66/360)amongminorethnicstudents,andnoethnicity-specific prevalence was seen (P > 0.05). Demodex folliculorum was the predominant species, with a prevalence of 50.54% (141/279), and mild infections were predominant among all infections (96.77%, 270/279), without severe infections seen. Multivariate nonconditional logistic regression analysis revealed that gender and roommates with Demodex infections were risk factors of Demodex infections, and the infection was not associated with ethnicity, place of origin or skin type. There were only 2.53% (37/1 463) of the subjects understanding the knowledge pertaining to the prevention and control of Demodex infection.

CONCLUSIONS

A relatively low prevalence of Demodex infection is detected in the facial skin of students from Kunming Medical University, and Demodex infection is associated with gender and roommates with Demodex infections. Health education pertaining to the prevention of Demodex infections is suggested to be intensified among university students.

[Study on the prevalence of Beijing genotype Mycobacterium tuberculosis and its relationship with second-line anti-tuberculosis drug resistance]

Objective: To explore the prevalence risk factors of Beijing genotype Mycobacterium tuberculosis (MTB) in Beijing and its correlation with second-line anti tuberculosis drug resistance. Methods: A total of 1 140 clinical MTB positive strains were collected from various districts in Beijing, and the drug sensitivity was detected by proportion method. Beijing genotype and non Beijing genotype MTB were identified by the method of Spoligotyping. Using SPSS 22.0 statistical software, chi square test or Fisher exact probability test was used to analyze the experimental data. Results: Among 1 140 MTB clinical isolates, 941 (82.5%) were Beijing genotype MTB, 199 were non Beijing genotype MTB. There were 663 males (70.5%) in Beijing genotype and 124 males (62.3%) in non Beijing genotype strains. There were significant differences in the proportion of males between the two genotypes [P=0.021, OR (95% CI):1.442 (1.048-1.985)]. There were 441 floating population (46.9%) in Beijing genotype MTB and 78 floating population (39.2%) in non Beijing genotype MTB. There was a significant difference in the proportion of floating population between the two genotypes [P=0.048,OR (95%CI):1.368(1.001-1.869)]. There were 129 patients (13.7%) aged 65 or older in Beijing genotype MTB, 40 patients (20.1%) aged 65 or older in non Beijing genotype MTB. The difference was statistically significant [P=0.021, or (95% CI): 0.631 (0.426-0.936)]. The resistance drug rates of Levofloxacin (Lfx), Amikacin (Am), Capreomycin (Cm), Para-aminosalicylic (PAS) in Beijing genotypes were 5.5% (52/941), 1.3% (12/941), 3.2% (30/941) and 3.0% (28/941), respectively, and those of non Beijing genotypes were 10.6% (21/199), 8.5% (17/199, 12.6% (25/199) and 11.6% (23/199), the difference was statistically significant (all P<0.05). There were 58 (6.2%) multidrug-resistant (MDR) strains in Beijing genotype MTB and 19 (9.5%) multidrug-resistant strains in non Beijing genotype. There was no significant difference in the proportion of MDR strains between Beijing genotype and non Beijing genotype (P>0.05). Conclusions: Beijing genotype MTB is widespread in Beijing and has a higher proportion in male population and floating population. Compared with non Beijing genotype, Beijing genotype MTB has a lower resistance rate to Lfx, Am, Cm and PAS, and there is no significant difference in the proportion of MDR-TB patients between the two genotypes.

Patient-reported outcomes after surgery or radiotherapy for localised prostate cancer: a retrospective study

INTRODUCTION

To compare the intermediate-term outcomes and patient-reported outcomes of robot-assisted laparoscopic prostatectomy (RALP) and radical external beam radiotherapy (RT) in Chinese patients with localised prostate cancer.

METHODS

This was a retrospective study of patients with localised prostate cancer diagnosed between 2010 and 2011 and treated with either RALP or RT. Baseline patient and disease characteristics, post-treatment complications, and latest disease status were retrospectively collected from hospital records. For assessment of patient-reported outcomes, the Chinese version of the Expanded Prostate Cancer Index Composite (EPIC) questionnaire was completed by the patients.

RESULTS

Ninety three patients aged 58 to 84 years were recruited. Thirty patients were treated by RALP (32.3%), whereas 63 received RT (67.7%). The RALP group had significantly lower baseline prostate-specific antigen levels than the RT group (P<0.001). More patients who underwent RALP reported urinary incontinence (70.0% vs 3.2%, P<0.001), whereas more patients who underwent RT reported other voiding symptoms (87.3% vs 50.0%, P<0.001) and perirectal bleeding (36.5% vs 0%, P<0.001) during follow-up. Of the 85 patients who were still alive at the time of the study, 52 (61.2%) returned completed questionnaires. Patients who underwent RALP had poorer median (interquartile range) EPIC urinary summary scores than patients who underwent RT [81.5 (18.3) vs 88.9 (17.9), P=0.016]. Urinary function [75.9 (20.4) vs 93.6 (16.2), P<0.001] and incontinence [60.5 (31.8) vs 91.8 (14.5), P<0.001] were also significantly worse in the RALP group. The bowel and sexual domain scores were similar between the two groups.

CONCLUSIONS

We found that RALP and RT were associated with different patterns of complications and patient-reported outcomes. Urinary incontinence was much more prevalent in the patients treated surgically. This may significantly affect patients' quality of life.

Urban-rural disparity of preventive healthcare utilisation among children under the universal health insurance coverage in Taiwan: a national birth cohort analysis

OBJECTIVE

In the context of universal health insurance coverage, this study aimed to determine whether urban-rural inequality still exists in preventive health care (PHC) amongst children in Taiwan.

STUDY DESIGN

Prospective cohort study.

METHODS

A total of 184,117 mothers and their children born in 2009 were identified as the study cohort. The number of children born in urban, satellite and rural areas was 40,176, 57,565 and 86,805, respectively. All children were followed for 7 years, before which a total of seven times PHC were provided by Taiwan's National Health Insurance (NHI) programme. Ordinal logistic regression models were used to associate urbanisation level with the frequency of PHC utilisation. Stratified analyses were further performed in accordance with the children's birth weight and the mothers' birthplace.

RESULTS

Children from satellite areas had higher utilisation for the first four scheduled PHC visits. Children living in urban areas received more PHC for the fifth and sixth scheduled visits. Compared with those from rural areas, children in satellite areas exhibited a small but significant increase in odds in PHC utilisation, with a covariate-adjusted odds ratio (aOR) of 1.04 and 95% confidence interval (CI) of 1.02-1.06. By contrast, no significant difference was observed between rural and urban areas (aOR = 1.01). Further stratified analyses suggest more evident urban-rural difference in PHC utilisation amongst children with low birth weight and foreign-born mothers.

CONCLUSIONS

Given a universal health insurance coverage and embedded mechanisms in increasing the availability of healthcare resources in Taiwan, a slight urban-rural difference is observed in PHC utilisation amongst children. Hence, sociodemographic inequality in utilisation of PHC still exists. This issue should be addressed through policy intervention.

Endogenous Retrovirus Activation as a Key Mechanism of Anti-Tumor Immune Response in Radiotherapy

The generation of DNA double-strand breaks has historically been taught as the mechanism through which radiotherapy kills cancer cells. Recently, radiation-induced cytosolic DNA release and activation of the cGAS/STING pathway, with ensuing induction of interferon secretion and immune activation, have been recognized as important mechanisms for radiation-mediated anti-tumor efficacy. Here we demonstrate that radiation-induced activation of endogenous retroviruses (ERVs) also plays a major role in regulating the anti-tumor immune response during irradiation. Radiation-induced ERV-associated dsRNA transcription and subsequent activation of the innate antiviral MDA5/MAVS/TBK1 pathway led to downstream transcription of interferon-stimulated genes. Additionally, genetic knockout of KAP1, a chromatin modulator responsible for suppressing ERV transcription sites within the genome, enhanced the effect of radiation-induced anti-tumor response in vivo in two different tumor models. This anti-tumor response was immune-mediated and required an intact host immune system. Our findings indicate that radiation-induced ERV-dsRNA expression and subsequent immune response play critical roles in clinical radiotherapy, and manipulation of epigenetic regulators and the dsRNA-sensing innate immunity pathway could be promising targets to enhance the efficacy of radiotherapy and cancer immunotherapy.

ATM Paradoxically Promotes Oncogenic Transformation via Transcriptional Reprogramming

The role of the ataxia-telangiectasia-mutated (ATM) gene in human malignancies, especially in solid tumors, remains poorly understood. In the present study, we explored the involvement of ATM in transforming primary human cells into cancer stem cells. We show that ATM plays an unexpected role in facilitating oncogene-induced malignant transformation through transcriptional reprogramming. Exogenous expression of an oncogene cocktail induced a significant amount of DNA double-strand breaks in human fibroblasts that caused persistent activation of ATM, which in turn enabled global transcriptional reprogramming through chromatin relaxation, allowing oncogenic transcription factors to access chromatin. Consistently, deficiencies in ATM significantly attenuated oncogene-induced transformation of human cells. In addition, ATM inhibition significantly reduced tumorigenesis in a mouse model of mammary cancer. ATM and cellular DNA damage response therefore play a previously unknown role in facilitating rather than suppressing oncogene-induced malignant transformation of mammalian cells. SIGNIFICANCE: These findings uncover a novel pro-oncogenic role for ATM and show that contrary to established theory, ATM does not always function as a tumor suppressor; its function is however dependent on cell type.

JMJD6 cleaves MePCE to release positive transcription elongation factor b (P-TEFb) in higher eukaryotes

More than 30% of genes in higher eukaryotes are regulated by promoter-proximal pausing of RNA polymerase II (Pol II). Phosphorylation of Pol II CTD by positive transcription elongation factor b (P-TEFb) is a necessary precursor event that enables productive transcription elongation. The exact mechanism on how the sequestered P-TEFb is released from the 7SK snRNP complex and recruited to Pol II CTD remains unknown. In this report, we utilize mouse and human models to reveal methylphosphate capping enzyme (MePCE), a core component of the 7SK snRNP complex, as the cognate substrate for Jumonji domain-containing 6 (JMJD6)’s novel proteolytic function. Our evidences consist of a crystal structure of JMJD6 bound to methyl-arginine, enzymatic assays of JMJD6 cleaving MePCE in vivo and in vitro, binding assays, and downstream effects of Jmjd6 knockout and overexpression on Pol II CTD phosphorylation. We propose that JMJD6 assists bromodomain containing 4 (BRD4) to recruit P-TEFb to Pol II CTD by disrupting the 7SK snRNP complex.

In animals, an enzyme known as RNA polymerase II (Pol II for short) is a key element of the transcription process, whereby the genetic information contained in DNA is turned into messenger RNA molecules in the cells, which can then be translated to proteins. To perform this task, Pol II needs to be activated by a complex of proteins called P-TEFb; however, P-TEFb is usually found in an inactive form held by another group of proteins. Yet, it is unclear how P-TEFb is released and allowed to activate Pol II.

Scientists have speculated that another protein called JMJD6 (Jumonji domain-containing 6) is important for P-TEFb to activate Pol II. Various roles for JMJD6 have been proposed, but its exact purpose remains unclear. Recently, two enzymes closely related to JMJD6 were found to be able to make precise cuts in other proteins; Lee, Liu et al. therefore wanted to test whether this is also true of JMJD6. Experiments using purified JMJD6 showed that it could make a cut in an enzyme called MePCE, which belongs to the group of proteins that hold P-TEFb in its inactive form.

Lee, Liu et al. then tested the relationships between these proteins in living human and mouse cells. The levels of activated Pol II were lower in cells without JMJD6 and higher in those without MePCE. Together, the results suggest that JMJD6 cuts MePCE to release P-TEFb, which then activates Pol II. JMJD6 appears to know where to cut by following a specific pattern of elements in the structure of MePCE. When MePCE was mutated so that the pattern changed, JMJD6 was unable to cut it. These results suggest that JMJD6 and related enzymes belong to a new family of proteases, the molecular scissors that can cleave other proteins.

The molecules that regulate transcription often are major drug targets, for example in the fight against cancer. Ultimately, understanding the role of JMJD6 might help to identify new avenues for cancer drug development.

Intercomparison of dose enhancement ratio and secondary electron spectra for gold nanoparticles irradiated by X-rays calculated using multiple Monte Carlo simulation codes

PURPOSE

Targeted radiation therapy has seen an increased interest in the past decade. In vitro and in vivo experiments showed enhanced radiation doses due to gold nanoparticles (GNPs) to tumors in mice and demonstrated a high potential for clinical application. However, finding a functionalized molecular formulation for actively targeting GNPs in tumor cells is challenging. Furthermore, the enhanced energy deposition by secondary electrons around GNPs, particularly by short-ranged Auger electrons is difficult to measure. Computational models, such as Monte Carlo (MC) radiation transport codes, have been used to estimate the physical quantities and effects of GNPs. However, as these codes differ from one to another, the reliability of physical and dosimetric quantities needs to be established at cellular and molecular levels, so that the subsequent biological effects can be assessed quantitatively.

METHODS

In this work, irradiation of single GNPs of 50 nm and 100 nm diameter by X-ray spectra generated by 50 and 100 peak kilovoltages was simulated for a defined geometry setup, by applying multiple MC codes in the EURADOS framework.

RESULTS

The mean dose enhancement ratio of the first 10 nm-thick water shell around a 100 nm GNP ranges from 400 for 100 kVp X-rays to 600 for 50 kVp X-rays with large uncertainty factors up to 2.3.

CONCLUSIONS

It is concluded that the absolute dose enhancement effects have large uncertainties and need an inter-code intercomparison for a high quality assurance; relative properties may be a better measure until more experimental data is available to constrain the models.

Immunological and biochemical evidence for identity of tartrate-resistant isoenzymes of acid phosphatases from human serum and tissues

We purified acid phosphatase isoenzyme 5b from a human spleen affected by leukemic reticuloendotheliosis and used it to produce a specific antiserum. The antiserum was used to show complete immunological identity among isoenzymes 5a and 5b in human serum, and 5b isolated from a giant-cell bone tumor and from the spleen of a case of Hodgkin's disease. Acid phosphatase 5b in a giant-cell bone tumor was isolated for biochemical characterization. Its pH optimum and substrate specificity were very similar to those of isoenzyme 5b from human spleen.

The extra domain A of fibronectin facilitates osteoclastogenesis in radicular cysts through vascular endothelial growth factor

AIM

To analyse the effects of the alternatively spliced fibronectin (FN) gene and its isoforms on osteoclastogenesis in radicular cysts.

METHODOLOGY

Specimens of radicular cysts were collected surgically from 22 patients whose radiolucent periapical areas were measured on digital panoramic radiographs before surgery. The associations between the radiolucent areas and FN isoforms, vascular endothelial growth factor (VEGF) expression or micro-vessel density, as well as the relationships amongst them, were analysed by immunohistochemical staining using the antibodies IST-9, BC-1, P1F11, VEGF and CD34. Fibroblasts isolated from those specimens were used to induce Trap + MNCs, and the effects of induction were assessed by blocking FN containing extra domain A (EDA + FN), COX-2 or VEGF in vitro. The effects of EDA exon knockout using CRISPR/Cas system were also assessed. Quantitative PCR was used to analyse relative expression of FN isoforms and osteoclastogenic genes. Data were analysed using linear regression, Spearman's rank correlation analysis, chi-square test and Student's t-test; P < 0.05 was considered significant.

RESULTS

Micro-vessel density and EDA + FN staining were positively associated with the size of radiolucent periapical areas (mm² ; P < 0.05), consistent with a positive association between Trap + MNCs and VEGF expression in fibroblasts (P < 0.05). Blocking the interaction between EDA + FN and fibroblasts inhibited Trap + MNC formation. In addition, EDA exon knockout decreased VEGF expression and inhibited Trap + MNC formation to the extent of blocking VEGF by bevacizumab, but osteoclastogenic induction was restored by recombinant VEGF. Using retrospective clinicopathological data, VEGF staining was shown to be positively associated with EDA + FN staining, micro-vessel density and the size of radiolucent areas (P < 0.05).

CONCLUSION

In fibrous capsules of radicular cysts, the alternatively spliced isoform EDA + FN generated by fibroblasts stimulated VEGF expression via an autocrine effect and then facilitated osteoclastogenesis. Both blockage of VEGF and EDA exon knockout could be used to inhibit bone destruction.

[Clinical characteristics and treatment options of hearing impairment caused by hyperbilirubinemia]

SummaryNeonatal hyperbilirubinemia is the most common clinical symptom in neonates. When the concentration of free bilirubin in blood is too high, it crosses through the blood-brain barrier and selectively deposits in specific brain nuclei to cause neurotoxicity and bilirubin neurological dysfunction. The auditory nervous system is highly sensitive to bilirubin. Therefore, auditory neuropathy is the most important or even the only clinical symptom of bilirubin neurological dysfunction. Chronic bilirubin encephalopathy can be classified to three types as mild, moderate and severe，according to the audiological manifestations and other neurological sequelae. Early recognition and intervention of bilirubin-induced hearing impairment is of great significance to improve the speech recognition rate of the referred children. This article reviews the most important studies about the clinical characteristics, pathogenesis and treatment of bilirubin-induced hearing impairment.

[Antimicrobial resistance and molecular epidemiology of foodborne Yersinia enterocolitica in Pudong New District, Shanghai]

Objective: To investigate the antimicrobial resistance and molecular epidemiology of foodborne Yersinia (Y.) enterocolitica in Pudong New District of Shanghai. Methods: Four kinds of raw food samples were collected in retail circulation sites in Pudong from 2012 to 2016. Cold enrichment method was used to isolate Y. enterocolitica and further detection of biotype, serotype, virulent genes, antimicrobial susceptibility of the isolates and pulsed field gel electrophoresis (PFGE) were conducted. Results: A total of 3 900 raw food samples were collected during this period, including poultry product (n=590), livestock product (n=1 074), aquatic product (n=1 488), vegetable (n=748), in which 111 (2.8%) were contaminated by Y. enterocolitica. The detection rates of Y. enterocolitica in poultry product samples (5.3%, 31/590) and livestock product samples (4.5%, 48/1 074) were higher than those in aquatic product samples (1.6%, 24/1 488) and vegetable samples (1.1%, 8/748). The predominant biotype was 1A (95.5%) and predominant serotype was O∶8 (42.3%). All the strains lacked ail, ystA, yadA and virF genes, which encoded pathogenic Y. enterocolitica. Seventy six (68.5%) strains harbored ystB gene, in which 35 (31.5%) belonged to 1A/O∶8/ystB pattern. Most strains were resistant to ampicillin (74.8%) and amoxicillin/clavulanic acid (70.3%), and non-sensitive rate to Cefoxitin was over 50.0%. No third generation cephalosporin or fluoroquinolone resistant strains were detected, but 38.7% (43/111) strains were multidrug resistant (MDR). Serotype O∶8 and O∶5 strains had 44 and 18 PFGE patterns, respectively. Conclusions: The main foodborne exposure sources of Y. enterocolitica in raw food were poultry and livestock products in Pudong New District. 1A/O∶8/ystB was the predominant pattern with potential pathogenicity despite lacks of typical pathogenic virulent genes. The antimicrobial resistant rates of Y. enterocolitica were at a low level, but MDR strains still existed. Molecular types of the isolates showed highly genetic diversity.

[Effects of two nanotopographies of ultraviolet-treated titanium implant surface on macrophage behaviour and inflammatory cytokines secretion]

Objective: To investigate the effects of two nanotopographies of ultraviolet (UV)-treated titanium surface on macrophage biological behaviour and inflammatory cytokines secretion, and to provide basis for clinical application of UV-treatment in dental implant modification. Methods: Titanium disks were allocated into two groups. Samples in one group were acid-etched in hydrofluoric acid (Acid Ti group), and those in the other group were acid-etched and anodized (Anodization group) to form two nanotopographies respectively. The surface morphology was evaluated by field-emission scanning electron microscopy (FE-SEM). The samples were stored in the dark for 8 weeks. Thirteen samples from each group were exposed to UV-irradiation for 48 h (Acid Ti+UV group and Anodization+UV group), UV-untreated samples from Acid Ti and Anodization groups served as control. Hydrophilicity of samples was measured using contact angle measuring device. After 4, 24 and 72 h of incubation, macrophage cell adhesion and proliferation were conducted using cell counting kit-8. Cytokine/chemokine secretions [tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1) and macrophage inflammatory protein-1α (MIP-1α)] were measured from cell culture supernatants at 24 and 72 h using magnetic luminex assay. Cell morphology was examined using FE-SEM after 2 h of incubation. Results: Micropitted/nanopillar and micropitted/nanotubular topographies were observed in Acid Ti group and Anodization group respectively. Contact angles in Acid Ti+UV and Anodization+UV groups (20.2°±2.8° and 0.0°±0.0°) were significantly smaller than those in the Acid Ti and Anodization groups (P<0.05). Cell adhesion and proliferation in all groups at 4 and 24 h showed no difference (P>0.05). Cell proliferation in Acid Ti+UV and Anodization+UV groups at 72 h were (0.92±0.13) and (1.10±0.08) respectively, which were significantly higher than those in Acid Ti and Anodization groups. TNF-α concentration in Acid Ti+UV and Anodization+UV groups at 72 h were (1.03±0.11) and (0.87±0.10) ng/L, MCP-1 were (301.7±50.3) and (240.8±18.7) ng/L, MIP-1α were (224.9±30.6) and (233.9±14.9) ng/L respectively, which were significantly lower than those in Acid Ti and Anodization groups (P<0.05). Conclusions: UV treatment can increase hydrophilicity of two titanium surface topographies, especially of Anodization+UV group. UV-treated titanium surfaces can promote macrophage proliferation and reduce the inflammatory response in vitro.

Effect of tannins and cellulase on growth performance, nutrients digestibility, blood profiles, intestinal morphology and carcass characteristics in Hu sheep

Objective

This study was conducted to evaluate the effects of tannins and cellulase on growth performance, nutrient digestibility, blood profiles, intestinal morphology, and carcass characteristics in Hu sheep.

Methods

A total of 48 three-month-old meat Hu sheep (25.05±0.9 kg) were blocked based on body weight, and randomly allotted to 4 treatments with 3 replicates of 4 sheep each. The experiment lasted for 80 d, and dietary treatments were as follows: i) CON, control diet; ii) TAN, CON+0.1% tannins; iii) CEL, CON+0.1% cellulase; iv) TAN+CEL, CON+0.1% tannins and 0.1% cellulase.

Results

Compared with CON, CEL, and TAN+CEL had greater (p<0.05) final body weight (FBW) and average daily gain but lower (p<0.05) feed conversion ratio, while FBW of TAN+ CEL was lower (p<0.05) than that of CEL. The apparent total tract digestibility (ATTD) of dry matter in TAN, CEL, and TAN+CEL groups were higher (p<0.05) than that in CON. CEL and TAN+CEL groups had greater (p<0.05) ATTD of crude fiber compared with TAN and CON, while TAN group had lower (p<0.05) ATTD of crude protein than other treatments. TAN, CEL, and TAN+CEL groups increased (p<0.05) serum globulin and alkaline phosphatase but decreased (p<0.05) albumin/globulin. Serum total protein was greatest for TAN+CEL, intermediate for TAN and CEL and least for CON (p<0.05). TAN+CEL group increased (p<0.05) dressing percentage compared with CON, while the backfat thickness of CEL was lower (p<0.05) than that of CON. The villus height of jejunum and ileum in CEL and TAN+CEL groups were greater (p<0.05) than that in CON, and the crypt depth and villus height: crypt depth of jejunum were increased (p<0.05) in TAN, CEL, and TAN+CEL groups.

Conclusion

The addition of tannins and cellulase together promoted nutrient digestion, liver protein synthesis and intestinal development and thus improved growth performance and carcass characteristics.

[An analysis of medical X-ray examination frequency in ten hospitals in Tianjin, China]

Objective: To investigate the usage frequency of radiological diagnosis devices in ten hospitals in Tianjin, China, and to provide a basis for the survey of medical radiation frequency in Tianjin. Methods: Ten hospitals from the ten districts in Tianjin were enrolled as subjects by a convenient sampling method. A survey was conducted to assess the general information and radiological diagnosis device information and usage frequency in those hospitals in 2016. The radiological examination frequency in Tianjin was estimated. Results: A total of 610 458 patients received radiological examinations in the sampled hospitals in 2016. In those patients, 371 882 received X-ray examinations for imaging and 238 576 for computed tomography (CT) ; there were slightly more female patients than male patients, suggesting a relatively equal gender distribution; patients older than 40 years accounted for 65.53%, which was the highest among all the age groups. Different types of radiological diagnosis devices were mostly used in tertiary and secondary hospitals. In Tianjin, the estimated frequency of X-ray examination for imaging and CT scanning was 451 and 188 per thousand people, respectively, in 2016. Conclusion: The frequency of radiological diagnosis is relatively high in the ten hospitals in Tianjin. The investigation of medical radiation in Tianjin needs to be improved.

UBE2N Promotes Melanoma Growth via MEK/FRA1/SOX10 Signaling

UBE2N is a K63-specific ubiquitin conjugase linked to various immune disorders and cancer. Here, we demonstrate that UBE2N and its partners UBE2V1 and UBE2V2 are highly expressed in malignant melanoma. Silencing of UBE2N and its partners significantly decreased melanoma cell proliferation and subcutaneous tumor growth. This was accompanied by increased expression of E-cadherin, p16, and MC1R and decreased expression of melanoma malignancy markers including SOX10, Nestin, and ABCB5. Mass spectrometry-based phosphoproteomic analysis revealed that UBE2N loss resulted in distinct alterations to the signaling landscape: MEK/ERK signaling was impaired, FRA1 and SOX10 gene regulators were downregulated, and p53 and p16 tumor suppressors were upregulated. Similar to inhibition of UBE2N and MEK, silencing FRA1 decreased SOX10 expression and cell proliferation. Conversely, exogenous expression of active FRA1 increased pMEK and SOX10 expression, and restored anchorage-independent cell growth of cells with UBE2N loss. Systemic delivery of NSC697923, a small-molecule inhibitor of UBE2N, significantly decreased melanoma xenograft growth. These data indicate that UBE2N is a novel regulator of the MEK/FRA1/SOX10 signaling cascade and is indispensable for malignant melanoma growth. Our findings establish the basis for targeting UBE2N as a potential treatment strategy for melanoma.Significance: These findings identify ubiquitin conjugase UBE2N and its variant partners as novel regulators of MAPK signaling and potential therapeutic targets in melanoma. Cancer Res; 78(22); 6462-72. ©2018 AACR.

Novel roles of apoptotic caspases in tumor repopulation, epigenetic reprogramming, carcinogenesis, and beyond

Apoptotic caspases have long been studied for their roles in programmed cell death and tumor suppression. With recent discoveries, however, it is becoming apparent these cell death executioners are involved in additional biological pathways beyond killing cells. In some cases, apoptotic cells secrete growth signals to stimulate proliferation of neighboring cells. This pathway functions to regenerate tissues in multiple organisms, but it also poses problems in tumor resistance to chemo- and radiotherapy. Additionally, it was found that activation of caspases does not irreversibly lead to cell death, contrary to the established paradigm. Sub-lethal activation of caspases is evident in cell differentiation and epigenetic reprogramming. Furthermore, evidence indicates spontaneous, unprovoked activation of caspases in many cancer cells, which plays pivotal roles in maintaining their tumorigenicity and metastasis. These unexpected findings challenge current cancer therapy approaches aimed at activation of the apoptotic pathway. At the same time, the newly discovered functions of caspases suggest new treatment approaches for cancer and other pathological conditions in the future.

Caspase-3 regulates the migration, invasion and metastasis of colon cancer cells

Caspase-3 (CASP3) is a major mediator of apoptosis activated during cellular exposure to cytotoxic drugs, radiotherapy or immunotherapy. It is often used as a marker for efficacy of cancer therapy. However, recent reports indicate that caspase-3 has also non-apoptotic roles such as promotion of tumor relapse and tumor angiogenesis. Therefore, the roles of caspase-3 in tumor progression remain to be defined clearly. In our study, we established caspase-3 knockout (KO) colon cancer cell lines by use of the CRISPR technology. In vitro, caspase-3 knockout HCT116 cells were significantly less clonogenic in soft agar assays. They were also significantly less invasive and more sensitive to radiation and mitomycin C than control cells. In vivo, CASP3KO cells formed tumors at rates similar to control cells but were significantly more sensitive to radiotherapy. They were also less prone to pulmonary metastasis when inoculated either subcutaneously or intravenously. At the mechanistic level, caspase-3 gene knockout appeared to cause reduced EMT phenotypes when compared to parental HCT116 cells. Indeed, they showed significantly increased E-cadherin expression, reduced N-cadherin, Snail, Slug and ZEB1 expression than control cells. Therefore, therapeutic targeting of caspase-3 may not only increase the sensitivity of cancer cell to chemotherapy and radiotherapy, but also inhibit cancer cell invasion and metastasis.

[Clinical characteristics and whole exon sequence study of a Chinese family with autosomal dominant lateral temporal lobe epilepsy]

Objective: To explore the genetic characteristics in a Chinese family with autosomal dominant lateral temporal lobe epilepsy (ADLTE) and analyze the correlation between genotype and phenotype. Methods: The natural history, clinical data and peripheral blood sample were collected in all patients and two healthy members of this ADLTE family. Whole exon sequence (WES) analysis strategy was used to explore the underlying mutations. Possible causative genetic variation was further confirmed by direct PCR and Sanger sequencing. The genotype-phenotype features were compared with previously reported cases. Results: A novel pathogenetic LGI1 frameshift mutation p.T134fs was identified in this study. The clinical phenotype was different from reported. Conclusion: This study reports a pathogenic LGI1 mutation in a Chinese ADLTE family for the first time, which suggests that LGI1 is a new genetic abnormality of ADLTE in Chinese.

[Preparation of chaperone-antigen peptide vaccine derived from human gastric cancer stem cells and its immune function]

Objective: To explore the method of extracting chaperone antigen peptide complexes from gastric cancer stem cells and its immune function. Methods: Gastric cancer stem cells and gastric cancer cells were screened by low temperature ultrasonic lysis. After salting out and dialysis, the lysate supernatant was processed with SDS-PAGE to analyze the expression of chaperone antigen peptide complexes, and then was separated and purified with CNBr-activated SepharoseTM 4B. Reverse high pressure liquid chromatography (HPLC), SDS-PAGE and Western blotting were used to analyze the purity and nature of the acquired albumen. Lymphocyte proliferation assay and lymphocytotoxicity assay were used to ditermine the immunological activity of the chaperone-antigen peptide complexes. Results: The chaperone antigen peptide complexes of gastric cancer stem cells were prepared and identified successfully, of which the main components were the antigen peptides of HSP60, HSP70, HSP90 and HSP110. 0.75 μg and 1.00 μg HSP70-antigen peptide and 1.00 μg HSP90-antigen peptide activated lymphocytes significantly. Their A(490) values were 0.26±0.03, 0.45±0.05 and 0.32±0.04, respectively, while the corresponding doses of HSP60-antigen peptide and HSP110-antigen peptide did not activate lymphocytes. The killing rates of 1.00 μg HSP70-antigen peptide and 1.00 μg HSP70 were (45.0±2.0)% and (16.0±2.0)%, respectively, showing a significant difference (P=0.012). Similarly, the killing rates of 1.00 μg HSP90-antigen peptide and 1.00 μg HSP90 were (36.0±5.0)% and (13.0±4.0)%, respectively, also showing a significant difference (P=0.048). Conclusions: The amount of chaperone antigen peptide complexes in gastric cancer cells is extremely low, but it is obviously increased in gastric cancer stem cells. After purification, the chaperone antigen peptide complexes with high purity can be prepared. The extracted chaperone antigen peptide complexes have stronger immunogenicity, and can be used to make tumor vaccine in vitro, which may have a good application value in the targeted therapy of gastric cancer.

Essential roles of Caspase-3 in facilitating Myc-induced genetic instability and carcinogenesis

The mechanism for Myc-induced genetic instability is not well understood. Here we show that sublethal activation of Caspase-3 plays an essential, facilitative role in Myc-induced genomic instability and oncogenic transformation. Overexpression of Myc resulted in increased numbers of chromosome aberrations and γH2AX foci in non-transformed MCF10A human mammary epithelial cells. However, such increases were almost completely eliminated in isogenic cells with CASP3 gene ablation. Furthermore, we show that endonuclease G, an apoptotic nuclease downstream of Caspase-3, is directly responsible for Myc-induced genetic instability. Genetic ablation of either CASP3 or ENDOG prevented Myc-induced oncogenic transformation of MCF10A cells. Taken together, we believe that Caspase-3 plays a critical, unexpected role in mediating Myc-induced genetic instability and transformation in mammalian cells.

Abstract 872: Noninvasive monitoring of endogenous Pdl1 expression by using a dual reporter system

Programmed death-ligand 1 (Pdl1) is a key immune checkpoint protein facilitating tumor escape from host immune system. Clinical approval of anti-PD1 and anti-PDL1 antibodies for the treatment of a variety of malignancies underscores the promise of immune checkpoint therapy. Further progress in this promising area of research is likely to come from better understanding of the mechanisms for regulation of immune checkpoint proteins such as PDL1. In the present study, we designed a dual reporter imaging system to monitor Pdl1 expression by use of the CRSPR-Cas9 technology. A fusion reporter that consists of eGFP and Luc2 was introduced into downstream of the endogenous Pdl1 gene, right before the stop codon, through CRISPR-Cas9 mediated homologous recombination. A P2A self-cleaving motif is inserted between the fusion reporter gene (eGFP-Luc2) and Pdl1. The reporter system was introduced into two murine tumor cell lines, 4T1 and B16F10. In vitro, an increase in eGFP intensity and bioluminescence of the reporter cells was observed after exposure to ionizing radiation or IFN-gamma, which has been reported to upregulate the expression of Pdl1. In vivo, we were able to observe radiation induced increase in bioluminescence signals from tumor established by use of the reporter cells. Our study therefore provided proof of principle for the use of our endogenous Pdl1 reporter imaging system to monitor the expression levels of Pdl1 in vitro and in vivo noninvasively and serially.

Citation Format: Min Zhou, Xinjian Liu, Fang Li, Chuan-Yuan Li. Noninvasive monitoring of endogenous Pdl1 expression by using a dual reporter system [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 872. doi:10.1158/1538-7445.AM2017-872

[Reducing maternal parenting stress of children with autism spectrum disorder: father's involvement]

Objective: To explore the relationship between fathers' nursing time and maternal parenting stress of children with autism spectrum disorder(ASD). Method: Mothers of 98 ASD children who were first diagnosed in the department of Child Health Care, Children's Hospital of Fudan University during June 2015 to January 2016 were included in the ASD group, with mothers of 92 typical children from a Community Maternal and Child Health Hospital and a kindergarten in the control group. The evaluation of parenting stress, parents' nursing time and other related factors were cross-sectionally analyzed. Interview was conducted with the following tools: Parental Stress Index-Short Form(PSI-SF)for maternal parenting stress, and self-made General Parenting Information Questionnaire for nursing time of both parents and other related factors. The relationships were analyzed by Multiple Linear Regression analysis and Wilcoxon Rank-Sum test. Result: Maternal parenting stress of ASD children had a significant negative correlation with father's nursing time in total score of parenting stress, PCDI domain and PD domain (t=-2.76, -2.98, -2.79; P=0.007, 0.004, 0.006), within which PD domain also included family annual income and mothers' nursing time (R(2)=0.22, 0.24, 0.25); while no such correlation was found in control group in terms of father's nursing time(P=0.22, 0.42, 0.06). Wilcoxon Rank-Sum test showed that in 62 (63.3%) double-income ASD families and 72(78.3%) double-income typical families, there were significant differences between ASD fathers' and ASD mothers'and typical fathers'nursing time(2.0(0.5, 2.1)vs. 3.5(2.4, 6.0)vs. 3.0(2.0, 4.7)h, t=-86.32、-49.65, all P<0.01). Conclusion: Lack of fathers' involvements was common in ASD children's families. Increasing these fathers' nursing time, as well as their enthusiasm and initiative in the family intervention could relieve maternal parenting stress and improve the intervention pattern of ASD children.

[Exploratory and confirmatory factor analyses for testing validity and reliability of the Chinese language questionnaire for urinary incontinence diagnosis]

OBJECTIVE

To translate questionnaire for urinary incontinence diagnosis (QUID) into Chinese and to test its reliability and validity.

METHODS

The English version of QUID was translated into Chinese. The clinaical data of 95 patinents with urinary incontinence who were test by urinary dynamic study in Peking Union Medical College Hospital from May 2014 to May 2015 were analyzed prospectively. The reliability of QUID was evaluated by completing QUID twice. The validity of QUID was evaluated by the standard of urinary dynamic study.

RESULTS

Internal consistency (Cronbach α) of the items that pertained to stress urinary incontinence (SUI) and to urge urinary incontinence (UUI) were 0.91 and 0.89, respectively. Test-retest reliability (Kappa) was 0.795 and criterion validity (Kappa) was 0.62. Sensitivity and specificity were 83% (43/52) and 86% (37/43), respectively, for SUI, and 72% (13/18) and 86% (66/77), respectively, for UUI.

CONCLUSIONS

QUID has good reliability and validity. It could be used in Chinese urinary incontinence women.

[Hot research topics on cardiovascular diseases in occupational population: a bibliometric analysis]

Objective: To investigate the literature characteristics and research topics on cardiovascular diseases in the occupational population quantitatively via a bibliometric analysis, and to provide a reference for the selection of research directions. Methods: A search strategy was developed according to the words in Medical Subject Heading (MeSH) , and PubMed database was searched for articles on cardiovascular diseases in the occupational population published from 2006 to 2015. The information of published year, authors, journals, and MeSH words was extracted, frequently used MeSH words were screened out, and a cluster analysis was performed for frequently used MeSH words. Results: A total of 1 272 articles were found, and about 150 articles were published annually from 2011 to 2015. Most articles were published in Occupational and Environmental Medicine, and the author Tohr Nilsson had the highest number of published articles. The influencing factors mainly included occupational mental stress, smoking, and working system, and the health outcomes attracting the most attention were hypertension, hand-arm vibration, ischemic heart disease, and myocardial infarction. The articles were clustered into 5 types, and 5 hot topics were summarized. Conclusion: The bibliometric analysis of cardiovascular diseases in occupational population shows that hypertension and hand-arm vibration are hot research topics, which can provide a reference to researchers.

Fermentation of Foc TR4-infected bananas and Trichoderma spp

Fusarium wilt (also known as Panama disease) is one of the most destructive banana diseases, and greatly hampers the global production of bananas. Consequently, it has been very detrimental to the Chinese banana industry. An infected plant is one of the major causes of the spread of Fusarium wilt to nearby regions. It is essential to develop an efficient and environmentally sustainable disease control method to restrict the spread of Fusarium wilt. We isolated Trichoderma spp from the rhizosphere soil, roots, and pseudostems of banana plants that showed Fusarium wilt symptoms in the infected areas. Their cellulase activities were measured by endoglucanase activity, β-glucosidase activity, and filter paper activity assays. Safety analyses of the Trichoderma isolates were conducted by inoculating them into banana plantlets. The antagonistic effects of the Trichoderma spp on the Fusarium pathogen Foc tropical Race 4 (Foc TR4) were tested by the dual culture technique. Four isolates that had high cellulase activity, no observable pathogenicity to banana plants, and high antagonistic capability were identified. The isolates were used to biodegrade diseased banana plants infected with GFP-tagged Foc TR4, and the compost was tested for biological control of the infectious agent; the results showed that the fermentation suppressed the incidence of wilt and killed the pathogen. This study indicates that Trichoderma isolates have the potential to eliminate the transmission of Foc TR4, and may be developed into an environmentally sustainable treatment for controlling Fusarium wilt in banana plants.

Caspase 3 in dying tumor cells mediates post-irradiation angiogenesis

Cytotoxic radiotherapy unfavorably induces tumor cells to generate various proangiogenic substances, promoting post-irradiation angiogenesis (PIA), which is one of major causes of radiotherapy failure. Though several studies have reported some mechanisms behind PIA, they have not yet described the beginning proangiogenic motivator buried in the irradiated microenvironment. In this work, we revealed that dying tumor cells induced by irradiation prompted PIA via a caspase 3 dependent mechanism. Proteolytic inactivation of caspase 3 in dying tumor cells by transducing a dominant-negative version weakened proangiogenic effects in vitro and in vivo. In addition, inhibition of caspase 3 activity suppressed tumor angiogenesis and tumorigenesis in xenograft mouse model. Importantly, we identified vascular endothelial growth factor (VEGF)-A as a downstream proangiogenic factor regulated by caspase 3 possibly through Akt signaling. Collectively, these findings indicated that besides acting as a key executioner in apoptosis, caspase 3 in dying tumor cells may play a central role in driving proangiogenic response after irradiation. Thus, radiotherapy in combination with caspase 3 inhibitors may be a novel promising therapeutic strategy to reduce tumor recurrence due to restrained PIA.

Regulation of size and uniformity of In2O3 nanooctahedra

Rational regulation of the size and uniformity of nanoparticles has drawn great interests and shown widespread application, but this cannot be simply achieved by the vapor route. In this work, by adopting a chemical vapor deposition approach, the growth process was intricately regulated to guide the reagent supersaturation, and the large-scale growth of uniform-sized In2O3 nanooctahedra was realized. A one-time nucleation and synchronous growth mode controlled by the reagent supersaturation ratio is proposed to be responsible for the uniformity of size. Furthermore, a series of comparative experiments were conducted to study the size dependence on reaction duration, and temperature difference between the heating and depositing zones. This study demonstrates a feasible approach to prepare uniform-sized nanoparticles through precisely controlling the crystal growth process, and the developed growth strategy could be generalized to synthesize uniform-sized nanostructures of other material systems.

Rapid Reprogramming of Primary Human Astrocytes into Potent Tumor-Initiating Cells with Defined Genetic Factors

Cancer stem-like cells (CSC) are thought to drive brain cancer, but their cellular and molecular origins remain uncertain. Here, we report the successful generation of induced CSC (iCSC) from primary human astrocytes through the expression of defined genetic factors. Combined transduction of four factors, Myc, Oct-4, p53DD, and Ras, induced efficient transformation of primary human astrocytes into malignant cells with powerful tumor-initiating capabilities. Notably, transplantation of 100 transduced cells into nude mice was sufficient for tumor formation. The cells showed unlimited self-renewal ability with robust telomerase activities. In addition, they expressed typical glioma stem-like cell markers, such as CD133, CD15, and CD90. Moreover, these cells could form spheres in culture and differentiate into neuron-like, astrocyte-like, and oligodendrocyte-like cells. Finally, they also displayed resistance to the widely used brain cancer drug temozolomide. These iCSCs could provide important tools for studies of glioma biology and therapeutics development. Cancer Res; 76(17); 5143-50. ©2016 AACR.

Effect of SNX-2112 on proliferation of esophageal cancer cells via regulation of excision repair cross-complementing 1, epidermal growth factor receptor, and p53 expression

SNX-2112 is a potential molecular targeted therapeutic drug against esophageal cancer (EC). However, its exact mechanism of action remains to be explained. The aim of this study was to investigate the effect of SNX-2112 on excision repair cross- complementing 1 (ERCC1), epidermal growth factor receptor (EGFR), and p53, to elucidate the mechanism of action of SNX-2112 on EC. Fresh tumor sections were surgically obtained from 65 patients with EC, and the expression of ERCC1, EGFR, and p53 was determined by immunohistochemical staining. Furthermore, the effect of SNX-2112 (0.2 μM) on the proliferation of EC-9706 cells and the expression of ERCC1, EGFR, and p53 in these cells were analyzed by a cell proliferation assay and western blot, respectively. We observed a significant decrease and increase in ERCC1 (P = 0.001) and p53 (P = 0.043) expression, respectively, and no significant difference in EGFR (P = 0.59) expression, with the TNM stage of EC, which suggested that ERCC1 and p53 could be potential markers for the TNM stage of EC. We also observed a significant increase in ERCC1 expression, and decrease in p53 and EGFR expression, in EC-9706 cells treated with SNX-2112 (P < 0.05), indicating the regulation of EC by SNX-2112. Furthermore, SNX-2112 treatment induced a significant decrease in the proliferation of EC-9706, which confirmed the function of SNX- 2112. In summary, SNX-2112 inhibits the proliferation of EC cells by regulating the expression of ERCC1, EGFR, and p53.

[Surgical treatment of ventriculoperitoneal shunt guided by ultrasound to the patients with idiopathic intracranial hypertension]

OBJECTIVE

To investigate the clinical efficacy of ventriculoperitoneal shunt treatment to patients with idiopathic intracranial hypertension.

METHODS

The clinical data of 32 patients with idiopathic intracranial hypertension who were admitted to Henan Provincial People's Hospital from August 2011 to February 2014 were collected.The underlying diseases included occlusion of the superior sagittal sinus (2 cases) and occlusion of transverse sinus (2 cases), and all 4 cases had a history of chronic otitis media.Twenty eight cases, with a history of oral contraceptive drugs (2 cases) and unclear etiology (26 cases), had normal venous sinus confirmed by imaging examination.All of 32 patients underwent ventriculoperitoneal shunt.

RESULTS

The symptoms of 32 patients such as headache, nausea, and vomiting were relieved obviously after surgery.The symptom of visual impairment of 31 cases got better in varying degrees except that 1 case went blind before operation.Besides 2 cases of loss of follow-up, the remaining 30 cases were followed up for 2 years.Thirty cases had no perioperative infection.One case had infection 1 year after operation.No one had the shunt tube blockage.

CONCLUSIONS

Patients with idiopathic intracranial hypertension should be taken active surgical treatment when drug therapy fails and could obtain satisfactory clinical curative effect by accepting treatment of ventriculoperitoneal shunt.By intraoperative ultrasound guiding lateral ventricle puncture can be achieved accurately.

[Management of early bronchopleural fistula after pneumonectomy]

OBJECTIVE

To investigate the management of early bronchopleural fistula(BPF) within one month after pneumonectomy.

METHODS

A total of 30 cases developed BPF within one month after pneumonectomy in recent 30 years were reviewed from First Hospital of Jilin University. All patients were treated by reoperation, closed drainage with or without open thoracic window, or endobronchial glue.

RESULTS

Seventeen patients were returned to the operating room for reclosure of BPF, one patients died of BPF and 16 reoperations were successful.Twelve cases were treated by closed drainage with or without followed open thoracic window. In 6 patients who were managed by closed drainage alone, 2 cases died of BPF and 4 bronchopleural fistulas closed spontaneously. In 6 patients treated with closed drainage and later with open thoracic window, one case died of BPF. One patient successfully underwent endoscopic glue to close BPF with injection three times.

CONCLUSION

Within one month postoperatively, BPF without established empyema with pus should be reoperated if the patient had enough cardiopulmonary reserve and could there fore tolerate reoperation. Contamination of pleural space is not the contraindication to reoperation. Reclosure via original thoracotomy and repair the fistula with pedicled intercostal muscle flap are convenient and efficient. Drainage with or without followed open thoracic window is appropriate for the patients with limited cardiopulmonary reserve, impaired general condition, secondary to empyema with pus, early recurred cancer, or some small fistulas.

5-Fluorouracil induces apoptosis of colorectal cancer cells

5-Fluorouracil (5-FU) is widely used in chemotherapy for treatment of colorectal cancer. Leucine-rich repeat-containing G protein-coupled receptor (LGR) is known to participate in the occurrence and development of breast cancer by regulating the rebirth of tumor vessels. This study aimed to explore the proliferation and apoptosis of HCT116 colorectal cancer cells treated with 5-FU and related molecular mechanisms. 5-FU (20 μg/mL) was used to treat cultured HCT116 cells. An MTT test, flow cytometry, and colony formation assays were used to examine the proliferation and apoptosis of HCT116 cells. Western blotting was applied to detect the expression of the LGR4 protein in HCT116 cells. Small interference RNA or over-expression techniques were used to manipulate LGR4 expression in HCT116 cells and describe the proliferation and apoptosis of HCT116 treated with 5-FU. A dosage of 20 μg/mL 5-FU resulted in a significant decrease in the proliferation and apoptosis of HCT116 cells and significantly decreased expression levels of LGR4. The specific gene silence or over-expression of LGR4 in HCT116 cells increased and decreased the levels of apoptosis in HCT116, respectively. 5-FU induces apoptosis of colorectal cancer cells and inhibits proliferation by suppressing LGR4 proteins.

Direct DNA extraction method of an obligate parasitic fungus from infected plant tissue

Powdery mildew and rust fungi are obligate parasites that cannot live without host organisms. They are difficult to culture in synthetic medium in the laboratory. Genomic DNA extraction is one of the basic molecular techniques used to study the genetic structure of populations. In this study, 2 different DNA extraction methods, Chelex-100 and cetyltrimethylammonium bromide (CTAB), were used to extract DNA from euonymus powdery mildew and Puccinia striiformis f. sp Tritici. Polymerase chain reaction was carried out with a race-specific-marker rDNA-internal transcribed spacer sequence. Both DNA extraction methods were compared and analyzed. The results showed that both Chelex-100 and CTAB were effective for extracting genomic DNA from infected plant tissue. However, less DNA was required for the Chelex-100 method than for the CTAB method, and the Chelex-100 method involved fewer steps, was simpler and safer, and did not require organic solvents compared to the CTAB method. DNA quality was evaluated by polymerase chain reaction, and the results showed that genomic DNA extracted using the Chelex-100 method was better than that using CTAB method, and was sufficient for studying the genetic structure of population.

Influence of suppression of CapG gene expression by siRNA on the growth and metastasis of human prostate cancer cells

This study investigated CapG gene expression in prostate cancer cell lines; in addition, we explored the effects of CapG suppression on DU145 cell growth, and the underlying mechanism with which CapG affects DU145 cell growth and invasiveness. The expression of CapG and 18 related genes in DU145 cells was analyzed by flow cytometry, quantitative polymerase chain reaction (qPCR), CCK8 assay, western blot, and the trans-well assay. DU145 cells were transfected with designed small interfering RNA (siRNA). CapG expression was quantified by qPCR and western blot. DU145 cell proliferation and invasiveness was analyzed using the CCK8, flow cytometric, and trans-well assays. CapG, TMPRSS1, EGFR, ETS-1, ERBB2, AKT, Cyclin D1, P21, Bcl-2, and Bak1 gene and Bcl-2, Cyclin D1, and CapG protein expressions were significantly lower in the siRNA group compared to the negative control group (P < 0.05). The proliferation of CapG siRNA DU145 cells was lower than that of the two control groups, 48 h after transfection. The cell inhibition rate was 24.5, 35.4, and 16,5% at 24, 48, and 72 h, respectively. The growth curve indicated that CapG siRNA DU145 cells showed a significantly slower proliferation rate (P < 0.05). The trans-well assay showed a significant decrease in the migratory and invasive capacities of DU145 cells in the siRNA group (P < 0.05). The suppression of CapG expression caused a significant decrease in the proliferation, invasiveness, and metastasis of DU145 cells. The mechanism with which CapG, with other oncogenes, influences cancer cell cycle remains to be elucidated.

Doubly Q-switched Ho:LuAG laser with acoustic-optic modulator and Cr²⁺:ZnS saturable absorber

A doubly Q-switched (DQS) Ho:LuAG laser resonantly pumped by a 1.91-μm laser was first presented with an acoustic-optic modulator (AOM) and a Cr2+:ZnS saturable absorber. A comparison among the active Q-switched (AQS), passively Q-switched (PQS), and DQS laser performances was carried out. The maximum continuous wave (CW) output power of 6 W with the central wavelength of 2100.65 nm was obtained at an incident pump power of 35.2 W. Compared with CW laser, the AQS, PQS, and DQS lasers shared the same central wavelength of 2098.34 nm under the same incident pump power. The central wavelength of the AQS and DQS lasers remained constant with the change of AOM repetition frequency (RF). When the incident pump power was 35.2 W and the AOM RF was 15 kHz, the DQS Ho:LuAG laser at a maximum RF of 2.13 kHz achieved the maximum average output power of 4.95 W. At the AOM RF of 10 kHz, the DQS Ho:LuAG laser achieved the shortest pulse width of 40.4 ns with the highest peak power of 61.5 kW. At an incident pump power of 35.2 W, the PQS Ho:LuAG laser obtained the shortest pulse width of 46.1 ns, corresponding to the RF of 2.25 kHz. Experiment results showed that the pulse width could be compressed effectively with a significant increase of peak power for a 2-μm DQS laser.

Construction and expression of prokaryotic expression vectors fused with genes of Magnaporthe oryzae effector proteins and mCherry

The aim of the current study was to investigate the prokaryotic expression of the Magnaporthe oryzae effector genes BAS1 and BAS4 fused to the fluorescent protein mCherry. Based on previous polymorphic analysis of BAS1 and BAS4 in rice blast strains using PCR, blast strains containing the PCR products of BAS1 and BAS4 were selected for liquid culture for total RNA extraction. For PCR analysis, cDNA was selected as a template to amplify the coding region of BAS1 and BAS4, the plasmid pXY201 was selected as template to amplify the mCherry sequence, and the three sequences were cloned into pMD®19-T vectors. Positive recombinant plasmids were digested using two restriction enzymes and the cleaved fragments of BAS1 and mCherry and BAS4 and mCherry were ligated to pGEX-4T-1 vectors and expression was induced using IPTG. The PCR results showed that the sequence sizes of BAS1, BAS4, and mCherry were 348, 309, and 711 bp, respectively, and these were cloned into pMD®19-T vectors. After digestion and gel purification, the fragments of BAS1 and mCherry, BAS4 and mCherry were ligated into pGEX-4T-1 vectors and expressed in Escherichia coli BL21 competent cells. The expressed proteins were approximately 60 kDa, corresponding to their theoretical size. Prokaryotic expression products of BAS1 and BAS4 fused to mCherry were presented in this study, providing a base for constructing prokaryotic expression vectors of pathogen effector genes fused to mCherry, which will contribute to further study of the subcellular localization, function, and protein interactions of these effectors.

Simulation on the molecular radiosensitization effect of gold nanoparticles in cells irradiated by x-rays

Abundant studies have focused on the radiosensitization effect of gold nanoparticles (GNPs) in the cellular environment with x-ray irradiation. To better understand the physical foundation and to initially study the molecular radiosensitization effect within the nucleus, a simple cell model with detailed DNA structure in the central nucleus was set up and complemented with different distributions of single and multiple GNPs in this work. With the biophysical Monte Carlo simulation code PARTRAC, the radiosensitization effects on both physical quantities and primary biological responses (DNA strand breaks) were simulated. The ratios of results under situations with GNPs compared to those without GNPs were defined as the enhancement factors (EFs). The simulation results show that the presence of GNP can cause a notable enhancement effect on the energy deposition within a few micrometers from the border of GNP. The greatest upshot appears around the border and is mostly dominated by Auger electrons. The enhancement effect on the DNA strand breakage becomes smaller because of the DNA distribution inside the nucleus, and the corresponding EFs are between 1 and 1.5. In the present simulation, multiple GNPs on the nucleus surface, the 60 kVp x-ray spectrum and the diameter of 100 nm are relatively more effective conditions for both physical and biological radiosensitization effects. These results preliminarily indicate that GNP can be a good radiosensitizer in x-ray radiotherapy. Nevertheless, further biological responses (repair process, cell survival, etc) need to be studied to give more accurate evaluation and practical proposal on GNP's application in clinical treatment.

Construction of overexpression vectors of Magnaporthe oryzae genes BAS1 and BAS4 fusion to mCherry and screening of overexpression strains

The aim of this study was to construct overexpression vectors and selecting strains of the Magnaporthe oryzae effectors BAS1 and BAS4. Primer pairs of BAS1, BAS4, and mCherry were designed based on their known nucleotide sequences. The coding sequences of BAS1 and BAS4 were amplified, and the pXY201 plasmid was selected as a template to amplify the mCherry sequence. Fragments of BAS1 and mCherry, and BAS4 and mCherry were ligated into the pCAMBIA1302 vector. The recombinant pCAMBIA-BAS1-mCherry and pCAMBIA-BAS4-mCherry plasmids were transformed into E. coli DH5α competent cells. Transformants were screened by PCR, and plasmids from the positive transformants were extracted by enzymatic digestion to obtain pCAMBIA-BAS1-mCherry and pCAMBIA-BAS4-mCherry. The pCAMBIA-BAS1-mCherry and pCAMBIA-BAS4-mCherry plasmids were transformed into protoplasts of rice blast strains and the transformed strains were screened by PCR using primer pairs against the hygromycin gene. The result showed that the PCR products corresponded with the theoretical sizes. RT-PCR was used to analyze the expression of BAS1 and BAS4 in five transformed strains of BAS1 and BAS4, and the result showed that the higher expression level of the two genes was occurred in five transformant strains comparing to wild-type strain A3467-40 (the strain containing BAS1 and BAS4), but there was no difference among the five overexpression strains. The sporulation and spore germination of transformed strains was higher than in wild type strain, and there was no difference in the germination time. Construction of overexpression vectors and strains of M. oryzae effectors BAS1 and BAS4 provide reference material for other new effectors.

Redefining the roles of apoptotic factors in carcinogenesis

In a recent study we reported that mammalian cells exposed to stress such as ionizing radiation can survive with activation of caspase-3 or caspase-7. We found that sublethal activation of the executioner caspases promotes chemical- and radiation-induced genetic instability and carcinogenesis, in contrast to their perceived roles as tumor suppressors.

Caspase-3 promotes genetic instability and carcinogenesis

Apoptosis is typically considered an anti-oncogenic process since caspase activation can promote the elimination of genetically unstable or damaged cells. We report that a central effector of apoptosis, caspase-3, facilitates rather than suppresses chemical- and radiation-induced genetic instability and carcinogenesis. We found that a significant fraction of mammalian cells treated with ionizing radiation can survive despite caspase-3 activation. Moreover, this sublethal activation of caspase-3 promoted persistent DNA damage and oncogenic transformation. In addition, chemically induced skin carcinogenesis was significantly reduced in mice genetically deficient in caspase-3. Furthermore, attenuation of EndoG activity significantly reduced radiation-induced DNA damage and oncogenic transformation, identifying EndoG as a downstream effector of caspase-3 in this pathway. Our findings suggest that rather than acting as a broad inhibitor of carcinogenesis, caspase-3 activation may contribute to genome instability and play a pivotal role in tumor formation following damage.

Effects of anodic titanium dioxide nanotubes of different diameters on macrophage secretion and expression of cytokines and chemokines

OBJECTIVES

To investigate effects of TiO2 nanotubes of different diameters on J744A.1 macrophage behaviour, secretion and expression of pro-inflammatory cytokines and chemokines.

MATERIALS AND METHODS

Macrophage-like J744A.1 cells were cultured on three types of Ti surface: mechanically polished titanium plus 30 and 80 nm TiO2 nanotube surfaces, for 4, 24 and 48 h. Macrophage adhesion and proliferation were assessed using CCK-8 assay. Levels of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) and chemokines (MCP-1 and MIP-1α) secreted into the supernatant were measured using the Cytometric Bead Arrays kit. TNF-α, MCP-1 and MIP-1α gene expression were quantitatively analysed by real-time PCR.

RESULTS

These show that TiO2 nanotube surfaces, especially of 80 nm TiO2 nanotube, benefited macrophage adhesion and proliferation, and reduced protein secretion and mRNA expression of TNF-α, MCP-1 and MIP-1α. IL-1β and IL-6 were undetectable on all the surfaces at all times.

CONCLUSIONS

TiO2 nanotube surfaces, especially of 80 nm TiO2 nanotube, reduced inflammatory response in vitro, which might be part of a basis for rapid osseointegration in implants with TiO2 nanotube surfaces in animal studies.

The effects of recombinant human epithelialgrowth factor and protein-free calf blood extract for recovery of corneal mechanical epithelial defects healing and neovascularization

OBJECTIVE

This study was undertaken to investigate the effects of recombinant human epidermal growth factor (rhEGF) and protein-free calf blood extract on corneal wound healing and neovascularization.

MATERIALS AND METHODS

An rabbit central corneal wound and neovascularization model was established in rabbits. One eye of each group was chosen randomly for topical administration of protein-free calf blood extract, rhEGF, or NS (physiological saline), and variability in the area of corneal epithelial wound healing and neovascularization was observed.

RESULTS

On days 1 and 2, the healing rate of corneal epithelium was various among the protein-free calf blood extract group, rhEGF group and NS group (F=6.475, p=0.012). The healing rate of corneal epithelium in the rhEGF group was better than the protein-free calf blood extract group (p=0.004) and NS group (p=0.041) on day 1. The corneal neovascularization area in the protein-free calf blood extract group was less than that of rhEGF group (p=0.04) and NS group (p=0.008) on day 18.

CONCLUSIONS

rhEGF had better promotive effect on corneal epithelial wound healing than the protein-free calf blood extract in the advanced phase (within 2 days). Both rhEGF and protein-free calf blood extract were not found to promote.

Development of the charge exchange recombination spectroscopy and the beam emission spectroscopy on the EAST tokamak

Charge eXchange Recombination Spectroscopy (CXRS) and Beam Emission Spectroscopy (BES) diagnostics based on a heating neutral beam have recently been installed on EAST to provide local measurements of ion temperature, velocity, and density. The system design features common light collection optics for CXRS and BES, background channels for the toroidal views, multi-chord viewing sightlines, and high throughput lens-based spectrometers with good signal to noise ratio for high time resolution measurements. Additionally, two spectrometers each has a tunable grating to observe any wavelength of interest are used for the CXRS and one utilizes a fixed-wavelength grating to achieve higher diffraction efficiency for the BES system. A real-time wavelength correction is implemented to achieve a high-accuracy wavelength calibration. Alignment and calibration are performed. Initial performance test results are presented.