[Analysis of types and treatment methods of cervical massive hemorrhage].

Objective: To summarize the classification and clinical treatment experience of cervical massive hemorrhage in multiple centers. Methods: From April 2012 to October 2020, clinical data of 42 patients with cervical massive hemorrhage were retrospectively analyzed, including 27 cases from Shanghai Changzheng Hospital, 7 cases from Hunan Provincial People's Hospital, 4 cases from Longkou People's Hospital and 4 cases from Laizhou People's Hospital. According to bleeding position (P), bleeding vessel (V), cerebral blood supply (C), and the presence or absence of associated injury (A), 42 patients were classified as "PVCA", and summarize the methods of pre-hospital emergency and in-hospital treatment based on the "ABC" treatment principles: airway rebuild (A), effective arterial hemostasis and bleeding stop (B), and cerebral blood flow reconstruction within the time window (C). Results: Within the 42 cases of cervical massive hemorrhage, there were 3 cases of type P1 (below cricoid cartilage), 28 cases of type P2 (cricoid cartilage-mandibular angle), 11 cases of type P3 (mandibular angle-skull base); 22 cases of type V1 (arterial hemorrhage), 11 cases of type V2 (main venous hemorrhage), 7 cases of type V3 (simple superficial vein or small artery hemorrhage), 2 cases of type V4 (mixed arteriovenous hemorrhage); 5 cases of type C0 (no symptoms of cerebral ischemia and neurological dysfunction), 33 cases of type C1 (transient cerebral ischemia without sensory disturbance), 4 cases of type C2 (symptoms of cerebral ischemia and neurological dysfunction); 39 cases of type A0 (no other system damage was involved) and 3 cases of type A1 (combined with other system damage). All 42 patients received operations, 25 patients received open surgery of vascular reconstruction+hematoma/foreign body removal (7 cases of vascular ligation, 14 cases of direct suture repair, 4 cases of vascular interposition), 17 patients received hybrid surgery (carotid angiography+covered stent repair+hematoma/foreign body removal). The surgical technique success rate the was 100%. All the hemorrhagic shock was corrected, hematoma compression was relieved, and the symptoms of cephalic ischemia were improved. There were 4 cases of local cranial nerve injury, 1 case of incision hematoma and 6 cases of postoperative hyper perfusion. During the average 14.3 months follow-up, there was no operation related myocardial infarction, stroke or death, no re-rupture or re-dissection, and 50% asymptomatic restenosis was found in 1 case one year after received covered stent endovascular repair. Conclusion: Based on the "PVCA" classification and "ABC" treatment principle, it is safe and effective to rescue cervical massive hemorrhage.

[Role of vitamin K-dependent protein Gas6 in the expression of endothelial cell adhesion molecule-1 and chemokines induced by Porphyromonas gingivalis lipopolysaccharide].

OBJECTIVE: Growth-arrest-specific protein 6 (Gas6) is a vitamin K-dependent protein and involved in cell proliferation, survival, adhesion and migration . Also it has been shown to play an important role in the inflammatory response .The aim of present study was to investigate the role of Gas6 in the process of the expression of adhesion molecules and chemokines of human umbilical vein endothelial cells (HUVECs) induced by Porphyromonas gingivalis lipopolysaccharide(P.g-LPS). METHODS: After up-regulation and down-regulation of the expression of Gas6, the vascular endothelial cells were stimulated with 1 mg/L P.g-LPS for 3 h and 24 h. Real-time quantitative polymerase chain reaction(real-time PCR) was taken to detect the expression of the cell adhesion molecules:intercellular adhesion molecule-1 (ICAM-1) and E-selectin, as well as chemokines:interleukin-8 (IL-8) and monocyte chemoattractant protein 1 (MCP-1). Wound healing assay was taken to observe the migration ability of endothelium cells in different groups. RESULTS: After 3 h of P.g-LPS stimulation, the expression of adhesion molecules and chemokine in the down-regulation group was not significantly different from that in the control group,while in the up-regulation group the decrease of E-selectin, ICAM-1, IL-8 and MCP-1 was 81%±0%, 47%±3%, 76% ± 3%, 26% ± 6% respectively. After 24 h of P.g-LPS stimulation, the expression of adhesion molecules and chemokine in down-regulation group was significantly higher than that in control group (2.06±0.07, 1.99±0.11, 3.14±0.15, 1.84±0.03 flod), while these molecules in the down-regulation group was significantly lower than in the control group (29%±1%, 62%±3%, 69%±1%, 41%±2%). Differences were statistically significant (P<0.01). Wounding healing assay showed that down-regulation of Gas6 enhanced migration ability of endothelial cells while up-regulation of Gas6 weakened this ability,which was consistent with the trend of real-time PCR result. CONCLUSION: Down-regulation of the Gas6 gene enhanced the expression of ICAM-1, E-selectin, IL-8 and MCP-1 in HUVECs after P.g- LPS stimulating, while up-regulaiton of the Gas6 gene weakened the expression of ICAM-1, E-selectin, IL-8 and MCP-1 in HUVECs after P.g-LPS stimulating,suggesting that Gas6 may play a role in the process of endothelial cell adhesion.

Nanofibers promote HepG2 aggregate formation and cellular function.

Formation of hepatocyte spheroids is a necessary strategy for increasing liver-specific function in vitro. In this study, HepG2 cells showed good viability when grown on a polylactic acid-chitosan (PLA-CS) nanofiber and aggregated to form multicellular spheroids on the PLA-CS nanofibers with a diameter of approximately 100-200 mm in 5 days of culture, whereas no such aggregation was observed in cells cultured on 24-well plates. Hepatocyte spheroids formed on the PLA-CS nanofibers displayed excellent hepatic-related protein expression, such as albumin and urea, compared to HepG2 cells cultured on the 24-well plates. These results indicated that formation of the hepatocyte spheroids in nanofibers can increase and maintain hepatocyte functions for a longer time, supporting a new strategy for bioartificial liver development.

Development of a smart, anti-water polyurethane polymer hair coating for style setting.

OBJECTIVE: The goal of this work was to develop a novel polyurethane polymer coating for the surface of the hair that could be used for style setting via the shape memory effect (SME). The features of the films are in accordance with conventional hair styling methods used in the laboratory. METHODS: In this study, a new polyurethane polymer was synthesized; the morphology and mechanical behaviour of the coated hair were systematically investigated using a scanning electron microscope (SEM) and an Instron 5566 (with a temperature oven). The SME of the hair was tested using a 35-g weight and over five washing and drying cycles. RESULTS: The experimental result shows that the polyurethane polymer has effects on the mechanical behaviour of the hair. It indicates that the fixed shape (at 22°C) and recover rate (at 60°C) of different casted thickness films are similar. And the stress of the film becomes larger with increasing film thickness. Furthermore, the shape memory ability could be endowed with the hair styling using this polymer; the hair fibre could recover to the 65% of its original shape after five cycle deformation by 35 g mass under the heat-treated condition; it could recover its original setting styling even after 5th water washing and drying. The SEM results indicated that the microsurface of the hair is coated with the polymer membrane; it contributes to the shape memory ability of the coated hair to keep and recover to the original setting styling. The styling hair can return to the original hair because the polyurethane polymer can be washed out by water with suitable strength and shampoo totally which does not leave any flake. CONCLUSION: The polyurethane polymer-based hair setting agent has been developed successfully, and it could be coated evenly on the human hair with good hand feeling and SMEs. The SME is highly related to the quantity of polyurethane polymer solution, and the effect could be improved by increasing the solution quantity. The maximum deformation of the coated hair could be recovered 94% at 75°C, once its shape is changed by an external force. The treated hair can withstand warm water rinsing for at least five cycles, and it can keep 65% of its original setting style after water rinsing. The polyurethane polymer could be totally removed by shampooing the hair and hot towel covering for 5-10 min. This research provides an effective way for the development of new intelligent shaping agents.

Porcine bocaviruses: genetic analysis and prevalence in Chinese swine population.

In members of the Bocavirus genus, that contain three open reading frames (ORFs) of the Parvovirinae subfamily, porcine bocaviruses (PoBoVs) exhibit the most genetic diversity. Based on the ORF2-encoded viral protein (VP1) classification, the six reported porcine bocaviruses were grouped into four species: PoBoV1 (porcine boca-like virus or PBoLV), PoBoV2 (porcine parvovirus 4 or PPV4), PoBoV3 (PBoV1/PBoV2) and PoBoV4 (6V/7V), with PoBoV3 and PoBoV4 each having two genotype viruses. All four PoBoV species were detected in the 166 samples collected in 2010 from swine herds located in ten provinces of China. The detection rates for PoBoV1-4 were 28·9%, 6·6%, 19·3% and 39·7%, respectively. The co-infection combinations involving these six porcine bocaviruses in the collected samples were very complex. Furthermore, mixed infections with viruses from other families (porcine reproductive and respiratory syndrome virus, classic swine fever virus and porcine circovirus type 2) were also detected.

Tailoring deformation and superelastic behaviors of beta-type Ti-Nb-Mn-Sn alloys.

A group of Ti-25Nb-xMn-ySn (in wt%; x = 2, 4 and y = 1, 5) alloys were designed using the "BF-d-electron superelasticity" empirical relationship and subsequently were cast in order to investigate their microstructure, deformation and superelastic behaviors. Monolithic ß phase is found in all investigated alloys except in Ti-25Nb-2Mn-1Sn alloy which exhibits α"+ß dual-phase microstructure. During compression testing, the Ti-25Nb-2Mn-1Sn alloy fails and demonstrates sufficient plasticity of ~ 41% and ultimate compressive strength of ~ 1800 MPa, where other alloys do not fail within the load capacity of 100 kN. Among all the investigated alloys, Ti-25Nb-4Mn-1Sn alloy exhibits the highest yield strength (~ 710 MPa) while Ti-25Nb-2Mn-1Sn alloy possesses the highest hardness (~ 244 HV). In this work, yield strength is influenced by solid solution and grain boundary strengthening while hardness is affected by the amount of constituent phases in each alloy. Additionally, Ti-25Nb-4Mn-1Sn shows highest recoverable strain (2.35%) and superelastic recovery ratio (90%) during cyclic loading-unloading up to 3% strain level, with highest total energy absorption among the investigated alloys. Moreover, all the Ti-25Nb-xMn-ySn alloys display shear bands except that Ti-25Nb-2Mn-1Sn alloy displays shear bands together with some cracks on the outer surface of compressively deformed morphologies.

Strengthening mechanism and corrosion resistance of beta-type Ti-Nb-Zr-Mn alloys.

In order to achieve an effective balance between plasticity and strength, a group of Ti-26Nb-xZr-yMn (x = 4, 7, 10 wt% and y = 3, 5 wt%) alloys were designed to evaluate the effects of Mn and Zr on the microstructures, mechanical properties and strengthening effects of the TiNb system. All the investigated alloys illustrate a monolithic ß phase in their microstructure and they all possess substantial true plasticity (~160%) and true maximum strength (~ 950 MPa) without fracture during the compression tests within the load capacity of 100 kN. The contribution of solid-solution, grain-boundary and dislocation strengthening mechanisms have been evaluated using the strengthening model for ß Ti alloys for all the investigated alloys. Among the investigated alloys, Ti-26Nb-4Zr-5Mn demonstrates the highest true yield strength (654 MPa), dislocation density (2.45 × 1015 m-2) and hardness (242 HV) along with improved strain hardening ability in terms of strain hardening indices (0.42 and 0.09). Furthermore, based on the superior mechanical properties among the investigated alloys, the electrochemical performance of Ti-26Nb-4Zr-3Mn and Ti-26Nb-4Zr-5Mn have also been analyzed in this work. The electrochemical measurements show that both alloys have almost similar corrosion potential and corrosion current density in simulated body fluid, i.e., -0.45 V and 0.838 nA/cm2 for Ti-26Nb-4Zr-3Mn, -0.48 V and 0.839 nA/cm2 for Ti-26Nb-4Zr-5Mn, respectively.

Airy beams generated by a binary phase element made of polymer-dispersed liquid crystals.

Using polymer-dispersed liquid crystals (PDLCs), an electrically switchable binary phase pattern was fabricated to generate Airy beams through a programmable lithographic system. The right main lobe of the reconstructed Airy beam experienced 1.3 mm transverse deflection within 24 cm propagation distance. With a suitable voltage applied, the binary PDLC pattern can be erased due to the index match between polymers and liquid crystals. This versatile approach can be also used to generate other special beams with electrically tunable capability.

[Caries prevention effectiveness of aresin based sealant and a glass ionomer sealants: a report of 5-year-follow-up].

Objective: To evaluate and compare the caries prevention effectiveness of a resin-based sealant and a glass ionomer sealant on permanent first molars in 7- to 9-years-old school children. Methods: A randomized controlled, examiner-blinded, 5-year clinical trial was conducted in 19 primary schools in Dalian, Liaoning province. Totally 419 children (with 664 first molars) who had at least one sound permanent first molar with deep fissures or fissures with signs of non-cavitated lesions were recruited and stratified and allocated randomly into three parallel groups. A resin-based sealant was used in Group R (136 children with 219 first molars) and a glass ionomer sealant was used in Group G (130 children with 218 first molars). The third group (Group N, 153 children with 227 first molars) with none of the two sealants applied was served as blank control. Follow-up examinations were conducted at 0.5, 1, 2, and 5 years after sealing in order to assess the retention of the sealants and the incidence of caries occurrence. Chi-square test was adopted to compare the differences of caries incidence among the 3 groups. Generalized estimating equations (GEE) was used to analyze the effective factors of caries incidence. Results: During the 5-year follow-up period, 13.4% (23/172) of the teeth in Group R, 22.5% (40/178) of the teeth in Group G and 34.5% (57/165) of the teeth in Group N were diagnosed as having developed cavitated lesions. And the differences in the incidence of caries among the three groups was statistically significant (P<0.05). According to GEE, the resin-based sealant and the glass ionomer sealant were found to be the protection factors and the non-cavitated lesion before sealing was found to be the risk factor. The resin-based sealant was found to be the protection factor to the glass ionomer sealant when the blank control group was removed. Conclusions: Both resin-based sealant and glass ionomer sealant could effectively prevent the permanent first molars from the occurrence of carious lesions in 5 years. The resin-based sealant was superior to the glass ionomer sealant in caries prevention.

[Relationship between shift work and overweight/obesity in male steel workers].

Objective: To investigate the relationship between shift work and overweight/obesity in male steel workers. Methods: A questionnaire survey was conducted among the male steel workers selected during health examination in Tangshan Steel Company from March 2015 to March 2016. The relationship between shift work and overweight/obesity in the male steel workers were analyzed by using logistic regression model and restricted cubic splinemodel. Results: A total of 7 262 male steel workers were surveyed, the overall prevalence of overweight/obesitywas 64.5% (4 686/7 262), the overweight rate was 34.3% and the obesity rate was 30.2%, respectively. After adjusting for age, educational level and average family income level per month by multivariable logistic regression analysis, shift work was associated with overweight/obesity and obesity in the male steel workers. The OR was 1.19(95% CI: 1.05-1.35) and 1.15(95% CI: 1.00-1.32). Restricted cubic spline model analysis showed that the relationship between shift work years and overweight/obesity in the male steel workers was a nonlinear dose response one (nonlinear test χ2=7.43, P<0.05). Restricted cubic spline model analysis showed that the relationship between shift work years and obesity in the male steel workers was a nonlinear dose response one (nonlinear test χ2=10.48, P<0.05). Conclusion: Shift work was associated with overweight and obesity in the male steel workers, and shift work years and overweight/obesity had a nonlinear relationship.

Improved biological performance of magnesium by micro-arc oxidation.

Magnesium and its alloys have recently been used in the development of lightweight, biodegradable implant materials. However, the corrosion properties of magnesium limit its clinical application. The purpose of this study was to comprehensively evaluate the degradation behavior and biomechanical properties of magnesium materials treated with micro-arc oxidation (MAO), which is a new promising surface treatment for developing corrosion resistance in magnesium, and to provide a theoretical basis for its further optimization and clinical application. The degradation behavior of MAO-treated magnesium was studied systematically by immersion and electrochemical tests, and its biomechanical performance when exposed to simulated body fluids was evaluated by tensile tests. In addition, the cell toxicity of MAO-treated magnesium samples during the corrosion process was evaluated, and its biocompatibility was investigated under in vivo conditions. The results of this study showed that the oxide coating layers could elevate the corrosion potential of magnesium and reduce its degradation rate. In addition, the MAO-coated sample showed no cytotoxicity and more new bone was formed around it during in vivo degradation. MAO treatment could effectively enhance the corrosion resistance of the magnesium specimen and help to keep its original mechanical properties. The MAO-coated magnesium material had good cytocompatibility and biocompatibility. This technique has an advantage for developing novel implant materials and may potentially be used for future clinical applications.

An animal experimental study of porous magnesium scaffold degradation and osteogenesis.

Our objective was to observe the biodegradable and osteogenic properties of magnesium scaffolding under in vivo conditions. Twelve 6-month-old male New Zealand white rabbits were randomly divided into two groups. The chosen operation site was the femoral condyle on the right side. The experimental group was implanted with porous magnesium scaffolds, while the control group was implanted with hydroxyapatite scaffolds. X-ray and blood tests, which included serum magnesium, alanine aminotransferase (ALT), creatinine (CREA), and blood urea nitrogen (BUN) were performed serially at 1, 2, and 3 weeks, and 1, 2, and 3 months. All rabbits were killed 3 months postoperatively, and the heart, kidney, spleen, and liver were analyzed with hematoxylin and eosin (HE) staining. The bone samples were subjected to microcomputed tomography scanning (micro-CT) and hard tissue biopsy. SPSS 13.0 (USA) was used for data analysis, and values of P<0.05 were considered to be significant. Bubbles appeared in the X-ray of the experimental group after 2 weeks, whereas there was no gas in the control group. There were no statistical differences for the serum magnesium concentrations, ALT, BUN, and CREA between the two groups (P>0.05). All HE-stained slices were normal, which suggested good biocompatibility of the scaffold. Micro-CT showed that magnesium scaffolds degraded mainly from the outside to inside, and new bone was ingrown following the degradation of magnesium scaffolds. The hydroxyapatite scaffold was not degraded and had fewer osteoblasts scattered on its surface. There was a significant difference in the new bone formation and scaffold bioabsorption between the two groups (9.29 ± 1.27 vs 1.40 ± 0.49 and 7.80 ± 0.50 vs 0.00 ± 0.00 mm3, respectively; P<0.05). The magnesium scaffold performed well in degradation and osteogenesis, and is a promising material for orthopedics.

An animal experimental study of porous magnesium scaffold degradation and osteogenesis

Our objective was to observe the biodegradable and osteogenic properties of magnesium scaffolding under in vivo conditions. Twelve 6-month-old male New Zealand white rabbits were randomly divided into two groups. The chosen operation site was the femoral condyle on the right side. The experimental group was implanted with porous magnesium scaffolds, while the control group was implanted with hydroxyapatite scaffolds. X-ray and blood tests, which included serum magnesium, alanine aminotransferase (ALT), creatinine (CREA), and blood urea nitrogen (BUN) were performed serially at 1, 2, and 3 weeks, and 1, 2, and 3 months. All rabbits were killed 3 months postoperatively, and the heart, kidney, spleen, and liver were analyzed with hematoxylin and eosin (HE) staining. The bone samples were subjected to microcomputed tomography scanning (micro-CT) and hard tissue biopsy. SPSS 13.0 (USA) was used for data analysis, and values of P<0.05 were considered to be significant. Bubbles appeared in the X-ray of the experimental group after 2 weeks, whereas there was no gas in the control group. There were no statistical differences for the serum magnesium concentrations, ALT, BUN, and CREA between the two groups (P>0.05). All HE-stained slices were normal, which suggested good biocompatibility of the scaffold. Micro-CT showed that magnesium scaffolds degraded mainly from the outside to inside, and new bone was ingrown following the degradation of magnesium scaffolds. The hydroxyapatite scaffold was not degraded and had fewer osteoblasts scattered on its surface. There was a significant difference in the new bone formation and scaffold bioabsorption between the two groups (9.29±1.27 vs 1.40±0.49 and 7.80±0.50 vs 0.00±0.00 mm3, respectively; P<0.05). The magnesium scaffold performed well in degradation and osteogenesis, and is a promising material for orthopedics.