[Role of exosomal miRNA in tumor progression and its possible mechanism].

Exosome is a kind of biological nano-vesicle with a diameter of about 30-100 nm and is synthesized, secreted, and released in almost all types of body cells. Recent studies have found that exosomes contain a variety of functional proteins, including mRNA and microRNAs (miRNAs) and so on, which play an important role in the process of material transfer and information exchange in cells. In addition, the related-exosomal microRNAs secreted by tumor cells play an important role in regulating theoccurrence, development, invasion and metastasis of tumors and other biological processes.. Therefore, the study of tumor-related exosomal microRNAs will help us to explore the mechanism of tumor progression from the perspective of tumor gene regulation and new tumor markers, which will contribute to the early diagnosis, treatment, disease monitoring and prognosis evaluation.

[Evaluation of effect of oral health intervention on children in Shaoshan area of Hunan province].

OBJECTIVE: To understand the oral health status of children aged 3-12 in Shaoshan area of Hunan province and to evaluate the role of oral health educations based on community such as fluoride varnish, oral hygiene introduction in improving the oral health of children in the area so as to gain expe-rience. METHODS: The study used cluster sampling to select 3 kindergartens and 2 primary schools in different economic development areas of Shaoshan. Oral health status survey and interventions were conducted in December 2014 and September 2016, respectively. The average debris index, decayed missing filled teeth (deciduous teeth: dmft; permanent teeth: DMFT), and caries prevalence rate of children aged 3-6 years and 6-12 years were compared. At the same time, children aged 5 and 12 were used as representative populations to compare the indices as listed before and the caries prevalence rate of the first permanent molar in 12-year-old children was compared as well. Finally, health economic analysis was carried out based on the 2 years' result. RESULTS: In this study, 992 children and 896 children in 2014 and 2016 were included respectively. As for children aged 3-6 years, the average debris index and dmft in 2016 were significantly less than that in 2014 (P < 0.001, P < 0.001), and the difference of DMFT was not significant (P=0.419). Children aged 6-12 years showed the same result, the average debris index and dmft in 2016 were significantly less than those in 2014 (P < 0.001, P=0.013), and the difference in DMFT was not significant (P=0.674). 173 and 179 5-year-old children were included in 2014 and 2016 respectively, and the dmft showed significant difference (P=0.038); the caries prevalence rate was 75.7% and 71.5%, respectively, which was also not significant (P=0.370). With respect to the 12-year-old children, 65 and 104 children were included and the differences in dmft and DMFT were not significant (P=0.133, P=0.171). The caries prevalence of the first permanent molar in the 12-year-old children was 36.9% and 26.9%, whose difference was not significant (P=0.171). CONCLUSION: The application of fluoride varnish and oral health education can significantly reduce the dmft of children aged 3-12 years in Shaoshan area and significantly improve the oral hygiene status. DMFT, the caries prevalence rate of 5-year-old children's deciduous teeth and 12-year-old children's first permanent molar showed a decline.

Improving the long-term stability of Ti6Al4V abutment screw by coating micro/nano-crystalline diamond films.

Abutment screw loosening is the most common complication of implanting teeth. Aimed at improving the long-term stability of them, well-adherent and homogeneous micro-crystalline diamond (MCD) and nano-crystalline diamond (NCD) were deposited on DIO(®) (Dong Seo, Korea) abutment screws using a hot filament chemical vapor deposition (HFCVD) system. Compared with bare DIO(®) screws, diamond coated ones showed higher post reverse toque values than the bare ones (p<0.05) after cyclic loading one million times under 100N, and no obvious flaking happened after loading test. Diamond coated disks showed lower friction coefficients of 0.15 and 0.18 in artificial saliva when countered with ZrO2 than that of bare Ti6Al4V disks of 0.40. Though higher cell apoptosis rate was observed on film coated disks, but no significant difference between MCD group and NCD group. And the cytotoxicity of diamond films was acceptable for the fact that the cell viability of them was still higher than 70% after cultured for 72h. It can be inferred that coating diamond films might be a promising modification method for Ti6Al4V abutment screws.

Expression and clinical value of peroxiredoxin-1 in patients with pancreatic cancer.

BACKGROUND: Peroxiredoxin-1 (Prx-1) is an important protector for redox damage and its abnormal expression is continually reported in various tumors. This study aims to investigate the expression status of Prx-1 and evaluate its clinical value in pancreatic cancer. METHODOLOGY: Immunohistochemistry was used to detect Prx-1 expression in pancreatic cancer tissues and para-cancerous tissues. Enzyme-linked immunosorbent assay (ELISA) method was applied to detect the serum Prx-1 levels. RESULTS: The immunohistochemical results indicated that positive rate of Prx-1 was (p < 0.05) higher in pancreatic cancer tissues (74.4%) than in para-cancerous tissues (37.2%). Prx-1 expression was positively correlated with vascular endothelial growth factor (VEGF) and microvessel density (MVD) in cancer tissues. The ELISA results showed that patients with pancreatic cancer had a higher serum Prx-1 level than healthy subjects (31.2 ± 13.5 vs. 13.2 ± 11.9 ng/ml, p < 0.001). Prx-1 expression was correlated with aggressive clinicopathological parameter. The combination of serum Prx-1 and CA19-9, the area under the curve (AUC) was significantly higher than Prx-1 separate. Positive Prx-1 expression was correlated with disappointing overall survival (OS) (p = 0.002) and disease-free survival (DFS) (p < 0.001). Multivariate analysis showed that Prx-1 staining as an independent biomarker of poor OS (p = 0.035) and DFS (p < 0.001). CONCLUSION: These findings suggest that the levels of Prx-1 expression are significantly increased in pancreatic cancer. The up-regulated Prx-1 is closely related to tumor angiogenesis and acts as a promising tumor marker for diagnosis and prognosis of pancreatic cancer.

Effect of zinc-bearing zeolite clinoptilolite on growth performance, zinc accumulation, and gene expression of zinc transporters in broilers.

This study investigated Zn-bearing zeolite clinoptilolite (Zn-ZCP) as a Zn supplement on performance, organ or tissue development, Zn accumulation in tissues, and gene expression of Zn transporters in the duodenum of broilers. A total of 300 1-d-old Arbor Acres chickens were randomly allocated to 5 dietary treatments with 6 replicate cages of 10 birds per treatment for a 21-d feeding period. The treatments comprised a basal corn­soybean meal diet without supplemental Zn (the control) or similar diets supplemented with 80 mg/kg Zn from ZnSO4 or 20, 40, or 80 mg/kg Zn from Zn- ZCP, respectively. Supplementation of Zn-ZCP had a positive effect on G:F (linear, P < 0.05) and had tendency difference on ADG (linear, P < 0.1) of broilers during 1 to 21 d. Incremental Zn-ZCP inclusion in the diet increased the fresh weight of the pancreas (linear, P < 0.05) and tibia (linear, P < 0.05) in broilers on d 14. The same trend to the fresh weight of the tibia (linear, P < 0.05) and pancreas (linear, P < 0.05) was observed on d 21. Increasing Zn-ZCP level showed a linear response on Zn concentration in the liver (linear, P < 0.001), pancreas (linear, P < 0.05), and tibia (linear, P < 0.05) on d 14. The same trend of Zn concentrations in pancreas (linear, P < 0.05) and tibia (linear, P < 0.001) was observed on d 21. The mRNA levels of Zn transporter 2 (ZnT-2) and Zn transporter 5 (ZnT-5) in the duodenum of chicks fed the diet with 80 mg/kg Zn from Zn-ZCP did not differ from those of chicks fed the control diet, but both were lower (P < 0.05) than those of chicks fed ZnSO4 diet. Metallothionein (MT) mRNA levels of broilers fed the diet supplemented with 80 mg/kg Zn from Zn-ZCP or ZnSO4 was higher (P < 0.05) than that in the control group. Dietary treatments did not affect the mRNA expression of Zn transporter 1 (ZnT-1) or metal response element-binding transcription factor-1 (MTF-1). In conclusion, as a Zn supplement, Zn-ZCP was comparable to ZnSO4 for enhancing Zn accumulation and growth performance of broilers during 1 to 21 d. Broilers fed the diet with 80 mg/kg Zn from Zn-ZCP had different expressions of ZnT-2 and ZnT-5 in the duodenum compared with those fed the ZnSO4 diet.

Inducible nitric oxide inhibitor enhances the anti-tumor effect of cisplatin on CNE-2 cells by inducing cell apoptosis.

OBJECTIVE: Inducible nitric oxide (NO) synthase (iNOS) inhibitor S-methylisothiourea (SMT) has been reported to have anti-tumor effects on several types of cancers.  We aimed to investigate whether SMT can inhibit nasopharyngeal carcinoma cells CNE-2 proliferation through raise chemotherapy effect of diaminodichloroplatinum (DDP). MATERIALS AND METHODS: CNE-2 cells were treated with SMT, DDP and both of them respectively. MTT and colony-forming assay was performed to detect the proliferation effect of the treatment. Hoechst 33258 staining and apoptosis analysis were performed to investigate the apoptosis effect of chemotherapy. Additionally, the NO level was detected to estimate the activity of iNOS. RESULTS: CNE-2 cells expressed high level of iNOS. SMT can inhibit CNE-2 cells growth in a dose-dependent manner and have the effect on reducing dosage of DDP as well as enhancing the anti-tumor efficacy by promote cell apoptosis. CONCLUSIONS: Our findings suggested that SMT play a synergism role in the inhibition process of DDP on nasopharyngeal carcinoma, and SMT could be a promising therapeutic factor for cancer prevention.

The physical properties and response of osteoblasts to solution cast films of PLGA doped polycaprolactone.

Polycaprolactone films doped with poly(lactide-co-glycolide) (65:35) in 0, 10, 20, and 30 (wt%) were prepared and evaluated in terms of morphology, dynamic contact angle analysis, and thermal properties. The unique surface morphology of the doped PCL film resulted, without introducing significant microstructure disruption of PCL aggregation. The doped PCL film registered a lower contact angle and increased hydrophilicity. Osteoblast cells attached to all doped materials, the 10% and 20% doped materials demonstrating the greatest cell growth.

Surface properties and biocompatibility of solvent-cast poly[-caprolactone] films.

Poly(epsilon-caprolactone) (PCL) was dissolved in four solvent systems, chloroform, tetrahydrofuran, acetone and ethyl acetate, and cast onto glass Petri dishes. The surface properties of the resulting films were investigated. The extent to which their properties were determined by the solvent used in each case was quantified in terms of contact angle, surface morphology, attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), and the adhesion and proliferation of fibroblasts by direct contact. The surface of the PCL film in contact with glass was denoted the SG surface, and the other, which was exposed to the gas phase, a mixture of air and residual solvent vapour, was denoted the SA surface. In the case of hydrophobic solvent systems, the advancing contact angle of the SG surface was always lower than that of the SA surface. With hydrophilic solvent systems, on the other hand, the advancing contact angle of the SG film surface was higher when the contact angle of the Petri dish was higher than that of the gaseous mixture of the air and solvent vapour, otherwise it was lower or equal to that of the surface on which it was cast. The surface morphology was dictated by the solubility of PCL in the respective solvent systems: high dissolution solvents such as chloroform and tetrahydrofuran produced films that comprised PCL aggregates, the particles being larger in the case of chloroform, whereas the less efficient solvents (acetone and ethyl acetate) resulted in a filamentous structure. The ATR-FTIR results confirmed that the chemistry of the SA surfaces differed according to the solvent system used. Preliminary cell culture experiments carried out with the PCL films established that murine (L929) fibroblasts grew well on all surfaces regardless of the solvent used, although the rates of adhesion and proliferation were not as great as on tissue culture plastic controls. Of all the surfaces examined in this study, the cells favoured the SG aspect of ethyl acetate cast PCL films, the surface of which had the finest pore size and relatively low contact angle.

Compression-induced changes on physical structures and calcification of the aromatic polyether polyurethane composite.

It is generally accepted that stress causes calcification in both bio-prosthetic and polyurethane heart valves. However, simple uni-axially- and bi-axially-stretched samples did not yield a feasible model for the elaboration of the stress-induced calcification. In this study, heat compaction combined with the incorporation of polyethylene has been explored. Specimens of polyurethane were solution cast onto a porous bi-axially-drawn ultra-high-molecular-weight polyethylene film and then heat compacted under a pressure of 18 MPa at a chosen temperature for 1.5 h. The heat-compaction-induced calcification and physical changes of the polyurethane composite were evaluated using a 28-day in vitro calcification model and Attenuated Total Reflection-Fourier Transform-Infrared (ATR-FT-IR) spectroscopy. The calcification results indicated that heat-compaction-induced calcification was double that achieved without heat compaction. Heat-compacted polyurethane composite showed higher affinity to calcium ions than the non-heat compacted sample. The ATR-FT-IR results showed that the heat-compaction-induced physical changes include distortions of polymeric molecules and permanent changes of microstructures. The distortions of polymeric molecules could be deteriorated in contact with different media. The relaxation of the stressed structures of the polyether moiety might serve as a calcium trap and a heterogeneous nucleation site for calcification. The permanent changes of microstructures resulted from high distortions also served as affinity sites attracting calcification.

Effects of Tween-80 on the biodistribution of several lipophilic technetium-99m complexes.

The effects of Tween-80 on the biodistributions in mice of (99m)Tc-TBI, (99m)Tc-MIBI, (99m)TcN-TBI and (99m)TcN-MIBI were reported. The studies resulted that liver and blood uptakes of Tween-80 added (TA) complexes significantly lower than that of corresponding non-Tween-80 added (NTA) complexes. And the clearance rate from blood of TA complexes faster than that of NTA complexes. The optimal concentration of Tween-80 was about 1%. It can decrease the lipophilicity of (99m)Tc-complexes and improve the biological properties of the lipophilic (99m)Tc-complexes for myocardial imaging. It's worthy for further studies.

The role of cellular trace elements in oral carcinogenesis induced by 4-nitroquinoline 1-oxide(4NQO).

The aim of this study was to define the changes of cellular trace element concentration during the carcinogenesis process of Wistar rat palatine mucosa squamous epithelial cell induced by 4-nitroquinoline-1-oxide (4NQO). 4NQO was painted three times weekly for nineteen weeks on the palatine mucosae of 28 Wistar rats. Histologically normal, precancerous and squamous epithelial cell carcinoma tissues were obtained, and were studied by electron probe X-ray microanalysis. The measured elements were copper (Cu), zinc (Zn), selenium (Se), and molybdenum (Mo). The results were that both copper and zinc in the cellular nucleus and cytoplasm of the squamous epithelial carcinoma cells were significantly decreased. The concentration of cytoplasmic molybdenum significantly decreased in precancerous cells and significantly increased in squamous epithelial carcinoma cells. Minor changes in the concentration of selenium were observed in the process of normal to precancerous and then to cancerous cells. Cu/Zn increased in squamous epithelial carcinoma cells and Cu/Se and Zn/Se decreased in squamous epithelial carcinoma cells. These results suggest that the changes in intracellular copper, zinc, molybdenum are distinctly related to experimental oral carcinogenesis.

[The electron probe microanalysis on oral precancer treated by garlic].

OBJECTIVE: To evaluate the effect of 4 kinds of trace elements on experimental oral precancer treated by garlic. METHODS: The palatal mucosae of 42 Wistar rats were painted with 0.5% of 4-nitroquinololine-1-oxide(4NQO) three times weekly for 7 weeks by coating method. Then the animals were divided randomly into two groups. The treatment group was treated three times weekly with garlic solution at the posterior hard palatal mucosae by coating method, and in the control group, the vehicle-distilled water was used instead of garlic solution. At the 5th and 8th weeks of the treatment and the 7th week after the treatment was stopped, some animals were killed. The palatal epithelial cells were prepared and surveyed by electron probe microanalysis. RESULTS: During the treating period, garlic improved the levels of epithelial cells' nuclei copper, selenium, molybdenum and extranuclei selenium, molybdenum(P < 0.01), but it decreased the contents of epithelial cells' extranuclei copper and extra- and intranuclei zinc(P < 0.01). CONCLUSIONS: Garlic can treat the oral precancer by improving the levels of epithelial cells' nuclei copper, selenium, and molybdenum and extranuclei selenium and molybdenum.

[Study on trace elements in epithelial cells during oral carcinogenesis prevented by garlic].

Sixty-two Wistar rats were divided randomly into two groups, thirty-one for each group. The posterior hard palatal mucosae of all animals were painted thrice weekly with 0.5% 4-nitroquinoline 1-oxide(dissolved in dimethyl sulfoxide). Before that, the garlic injection solution and the distilled water were painted at the same place of the experimental and control group animals, respectively. All animals were killed in turn from the beginning of the experiment at random at the 10th, 13th, and 19th week. Then, trace elements of intranuclear and cytoplasm of epithelial cells or cancer cells at the mentioned weeks were surveyed by electron probe microanalysis. The results were that garlic decreased the levels of intranuclear and cytoplasm copper(P < 0.05); the levels of intranuclear and cytoplasm selenium at the 10th week and the 13th week(P < 0.05) and those of zinc at the 19th week (P < 0.01) increased. So, garlic inhibits oral carcinogenesis by changing concentrations of intranuclear and cytoplasm trace elements that is copper, zinc, selenium, and the ratio of the three elements.

Development of thin elastomeric composite membranes for biomedical applications.

A breakthrough has been made in blending of two immiscible biocompatible polymers to form thin transparent interpenetrating network composite membranes (CM) with exceptional improvement in properties. Two immiscible polymers, namely the biaxially drawn ultra high molecular weight polyethylene (UHMWPE) film and polyether polyurethane (PU) were used. The fabrication included solution casting and heat compaction. During the fabrication, the CM still preserved the orientation of UHMWPE fibers but introduced the interpenetration of PU in UHMWPE film. The intimate interaction of PU with UHMWPE fibers was viewed through the transparency of CM. Differential scanning calorimetry (DSC) data showed the melting temperature (Tm) of UHMWPE increased by about 10 degrees C in CM and about 5 degrees C in heat-compacted membranes (HCM). Morphological observations indicated that CM presented a layered structure while HCM was a dense material without obvious void inclusions. The ultimate tensile strength and relative Young's modulus of CM are about 62 MPa and 460 MPa, respectively. They are about four times greater in strength and 150 times greater in modulus compared with those of PU. Heat compaction resulted in a membrane with nearly five times the tensile strength and 50 times the Young's modulus of PU. The engineered ultimate strain of CM is about 26%, 8% more than that of the porous UHMWPE film while about 70% of HCM, which is a 50% increase achieved through heat compaction. The tensile fracture toughness is about 93 mJ for CM and 211 mJ for HCM, two and five times that for the porous UHMWPE film, respectively. The significant modification on the properties of the heat-compacted composite may raise broad interest in using the CM to develop membrane-related devices and organ covers in biomedical applications.

Hemoglobin Chongqing [alpha 2(NA2)Leu----Arg] and hemoglobin Harbin [alpha 16(A14)Lys----Met] found in China.

Hemoglobin Chongqing is a new slowly-moving and unstable hemoglobin variant with a high oxygen affinity, that was discovered in five members of a Chinese family in the suburb of Chongqing. Hemoglobin Harbin is another new rapidly-moving hemoglobin variant with slightly reduced stability and slightly increased oxygen affinity, found in a Chinese woman living in Harbin. The relative amounts of these two variants in the propositi were about 9% and 18%, respectively. Sequence analyses identified a Leu----Arg substitution at position alpha 2(NA2) of Hb Chongqing, and a Lys----Met substitution at position alpha 16(A14) of Hb Harbin.