[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.

[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.

[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.

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.

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.

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.