[Evaluation of accuracy of virtual occlusal definition in Angle class I molar relationship]

OBJECTIVE

To evaluate the accuracy of virtual occlusal definition in non-Angle class I molar relationship, and to evaluate the clinical feasibility.

METHODS

Twenty pairs of models of orthognathic patients were included in this study. The inclusion criteria were: (1) finished with pre-surgical orthodontic treatment and (2) stable final occlusion. The exclusion criteria were: (1) existence of distorted teeth, (2) needs for segmentation, (3) defect of dentition except for orthodontic extraction ones, and (4) existence of tooth space. The tooth-extracted test group included 10 models with two premolars extracted during preoperative orthodontic treatment. Their molar relationships were not Angle class I relationship. The non-tooth-extracted test group included another 10 models without teeth extracted, therefore their molar relationships were Angle class I. To define the final occlusion in virtual environment, two steps were included: (1) The morphology data of upper and lower dentition were digitalized by surface scanner (Smart Optics/Activity 102; Model-Tray GmbH, Hamburg, Germany); (2) the virtual relationships were defined using 3Shape software. The control standard of final occlusion was manually defined using gypsum models and then digitalized by surface scanner. The final occlusion of test group and control standard were overlapped according to lower dentition morphology. Errors were evaluated by calculating the distance between the corresponding reference points of testing group and control standard locations.

RESULTS

The overall errors for upper dentition between test group and control standard location were (0.51±0.18) mm in non-tooth-extracted test group and (0.60±0.36) mm in tooth-extracted test group. The errors were significantly different between these two test groups (P<0.05). However, in both test groups, the errors of each tooth in a single dentition does not differ from one another. There was no significant difference between errors in tooth-extracted test group and 1 mm (P>0.05); and the accuracy of non-tooth-extracted group was significantly smaller than 1 mm (P<0.05).

CONCLUSION

The error of virtual occlusal definition of none class I molar relationship is higher than that of class I relationship, with an accuracy of 1 mm. However, its accuracy is still feasible for clinical application.

[Application of three-dimensional reconstruction of the enhanced CT with iPlan CMF software in head and neck neoplasms]

OBJECTIVE

Three-dimensional reconstruction of the enhanced CT is increasingly becoming a valuable tool in head and neck neoplasms. The aim of this study is to reconstruct three-dimensional imaging of tumor and its surrounding important anatomical structure using iPlan CMF software, and to investigate the application of three-dimensional tumor mapping technique for the diagnosis and treatment of the head and neck neoplasms.

METHODS

In the study, 13 cases with head and neck tumors in Department of Oral and Maxilloficial Surgery, Peking University School and Hospital of Stomatology from June 2014 to June 2015 were studied using spiral CT scanning technology based on the same scanning condition. iPlan CMF software was used to read the original CT data, and surface shaded technology was applied to reconstruct the spatial relationship of the tumor, vessel and skull. The distance between the tumor and its surrounding important anatomical structure could be measured. iPlan CMF software was also used to accomplish the virtual osteotomy to expose the tumor, vessel and skull. The preoperative preparation, operative situation and postoperative complication were reviewed.

RESULTS

In this study 6 patients were male and 7 female. The age range was from 23 to 65 years, and the median patient age was 50 years. The three-dimensional reconstruction image clearly demonstrated the extent of the tumor size, location, and the relation to its surrounding important anatomical structure. According to the three-dimensional image, the surgical risk of the patients was evaluated. The preoperative preparation and surgeries were successfully performed for 10 patients. Blood transfusion for 3 patients was considered before the surgery and actually accomplished during the operation. The operations for 2 patients were performed with the help of doctors from other departments. Only one patient had hoarseness because the tumor resulted from the pneumogastric nerves. For 10 patients, the average operation time was (202±135) min, and the average operation bleeding was (235±252) mL. The other 3 patients were not suitable cases for surgery.

CONCLUSION

The three-dimensional reconstruction of enhanced CT image with iPlan CMF software is very helpful to make the treatment plan to avoid damaging important anatomical structures and postoperative complications.

Association of FOXF2 gene polymorphisms with ischemic stroke in Chinese Han population

Recently, a novel locus at chromosome 6p25 (rs12204590, near FOXF2) associated with an increased risk of stroke in European populations was identified. However, whether polymorphisms in FOXF2 are also associated with the incidence of ischemic stroke in other populations remains unknown. In this case-control study, 803 Chinese Han patients with ischemic stroke and 803 matched control individuals were enrolled. Four tag SNPs and rs12204590 located in or near FOXF2 were selected, and the associations between genotypes/alleles and ischemic stroke were analyzed. In our study, we did not detect an association between the previously reported locus rs12204590 and ischemic stroke. By the genotype analysis, a novel SNP rs1711972, near FOXF2, was observed to be associated with an increased risk of ischemic stroke(CA genotype, adjusted OR = 1.35; 95% CI, 1.07 to 1.70), but not significantly after Bonferroni corrections for multiple tests. However, in the subgroup analysis, we discovered that rs1711972 was associated with an increased risk of large-artery atherosclerotic stroke in the additive model (P = 0.020; CA genotype, adjusted OR = 1.50; 95%CI, 1.09 to 2.07) and dominant model (P = 0.010; OR = 1.47; 95%CI, 1.09 to 1.99). Collectively, these results indicate that a novel SNP near FOXF2 may influence the risk of large-artery atherosclerotic stroke in Chinese Han population.

[Effects and mechanisms of Notch signaling pathway on immune imbalance in chronic obstructive pulmonary disease]

Objective: To explore the role of Notch signaling pathway on immune imbalance in chronic obstructive pulmonary disease (COPD). Methods: Thirty BALB/c mice were randomly assigned into the healthy control group, COPD group, and COPD Gamma secretase inhibitors (GSI) group. Cigarette smoke exposure was used to establish the COPD model. T cells were enriched by filtering through nylon wool columns. The proportion of spleen-derived T-lymphocyte subsets was detected by flow cytometry. Real-time quantitative polymerase chain reaction (RT-PCR) and Western blot (WB) were used to detect the expression of splenic T cells' Notch1 and its downstream Hes1 mRNA and protein respectively. Results: The percentage of Th1, Th17 and Treg cells in CD₄^＋T cells of COPD mice (13.20±0.95, 10.22±0.45, 0.41±0.09)% were significantly increased compared with the healthy control group (8.07±0.44, 5.98±0.26, 0.26±0.05)%(all P<0.01). The proportion of Th1 and Th17 cells in COPD GSI group mice (9.48 ± 0.66, 7.70 ±0.39)% were significantly reduced compared with COPD group (all P<0.01). Ratio of Th1/Th2 in COPD group (18.70±4.12) was significantly increased compared with the healthy control group (12.63±1.91) (P<0.01), the percentage of Th17 and Treg in CD₄^＋ T cell increased 71% and 58% respectively. GSI decreased the ratios of Th1/Th2 and Th17/Treg (all P<0.01). Notch1 receptor and its downstream Hes1 mRNA expression (5.15±0.77, 1.92±0.32) and protein expression (0.85±0.04, 0.16±0.02) of COPD mice were significantly increased compared with the healthy group respectively [(1.00 ± 0.00, 1.00 ± 0.00) and (0.17±0.01, 0.09±0.01)] (all P<0.01). GSI significantly inhibited the expression of mRNA and protein in Notch1 and its downstream Hes1 (all P<0.01). Notch1 and Hes1 mRNA and protein expressions were correlated positively with Th1 and Th17 cells and negatively correlated with Th2 and Treg cells in COPD group(all P<0.05). Conclusion: In COPD mice, there was T-lymphocyte subsets imbalance, such as the increased of Th1, Th17 proinflammatory cells, Notch1 and its downstream Hes1 mRNA and protein levels were increased, and was associated with T-lymphocyte subsets imbalance. GSI could partially inhibit Notch1, Hes1 expression and Th1 and Th17 cells, and thus Notch signaling pathway was involved in the immune disorder of COPD mice.

[Diagnosis and treatment of traumatic optic neuropathy with internal carotid artery trauma]

Objective: To summarize our experience in the diagnosis of internal carotid artery trauma in patients with traumatic optic neuropathy, and to make recommendations for the treatment. Methods: The clinic data of 6 cases who had traumatic optic neuropathy with internal carotid artery trauma and who were admited in Department of Otorhinolaryngology, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University from Jan. 2013 to Dec. 2015 were analyzed retrospectively. Results: All 6 cases were monocular blindness. Four cases did not undergo nasal endoscopic optic nerve decompression because of the diagnoses of internal carotid artery trauma. One case was diagnosed after nasal endoscopic optic nerve decompression because of fatal bleeding during the operation. One case was diagnosed because of late-onset recurrent epistaxis. Among the 6 cases with internal carotid artery trauma, 3 cases were successfully treated with endovascular interventional treatment (stent embolization was used in one case, Coil embolization was used in two cases), and 3 patients refused treatment. Conclusions: The patients with traumatic optic neuropathy have the possibility of severe carotid artery trauma. Endoscopic optic nerve decompression is not suitable for these cases. It should pay more attention to patients with traumatic optic neuropathy. For suspected cases, vascular-enhanced computed tomography screening and digital subtraction angiography should be recommended and patients should be treated by endovascular intervention in a timely manner.

A series of intrinsically chiral gold nanocage structures

We present a series of intrinsically chiral gold nanocage structures, Au_9n+6, which are stable for n ≥ 2. These structures consist of an Au_9n tube which is capped with Au₃ units at each end. Removing the Au₃ caps, we obtain a series of intrinsically chiral gold nanotube structures, Au_9n, which are stable for n ≥ 4. The intrinsic chirality of these structures results from the helicity of the gold strands which form the tube and not because an individual Au atom is a chiral center. The symmetry of these structures is C₃ and substructures of gold hexagons with a gold atom in the middle are particularly prominent. We focus on the properties of Au₄₂ (C₃) and Au₁₀₅ (C₃) which are the two smallest gold nanocage structures to be completely tiled by these Au₇ "golden-eye" substructures. Our main focus is on Au₄₂ (C₃) since gold clusters in the 40-50 atom regime are currently being investigated in gas phase experiments. We show that the intrinsically chiral Au₄₂ cage structure is energetically comparable with previously reported achiral cage and compact Au₄₂ structures. Cage structures are of particular interest because species can be encapsulated (and stabilized) inside the cage and we provide strong evidence that Au₆@Au₄₂ (C₃) is the global minimum Au₄₈ structure. The intrinsically chiral gold nanocage structures, which exhibit a range of size-related properties, have potential applications in chiral catalysis and as components in nanostructured devices.

[Effects of PI3Kδ-RhoA pathway on phagocytosis defect of alveolar macrophages in a mouse model of chronic obstructive pulmonary disease]

Objective: To investigate effects of Phosphoinositide3-Kinases (PI3Kδ)-Ras homolog gene family member A(RhoA) pathway on phagocytosis deficiency of alveolar macrophages (AMs) in a mouse model of chronic obstructive pulmonary disease (COPD). Methods: Twenty mice were exposed to cigarette smoking to establish the COPD model, with 20 mice as the control group. AMs were isolated from lung tissue by discontinuous density gradient centrifugation and then divided into a healthy control group, a COPD group, a healthy IC87114 group and a COPD IC87114 group. The culture of IC87114 group was mixed with a final concentration of 1 nmol/L IC87114 for 24 hours. Mean fluorescence intensity (MFI) and the positive percent of AMs engulfing flurescein isothiocyanate-labeled Escherichina coli (FITC-E.coli) (AM%) were detected by flow cytometry. Real-Time PCR(RT-PCR)and Western blot were applied to detect mRNA and protein. G-LISA RhoA Kit was used to detect the activity of RhoA, and laser scanning confocal microscopy was used to observe the cytoskeleton structure of AMs. Results: Phagocytosis of AM: MFI and AM %in the COPD group [(4 512±517), (32.2±4.6)%] were decreased than those in the healthy control group [(9 857±1 042), (68.0±4.0)%, all P<0.01]. Compared with the COPD group, MFI and AM% in the COPD IC87114 group [(6 894±472), (50.6±2.1)%] were increased (all P<0.01). The expressions of mRNA and protein of PI3Kδ in the COPD group (3.14±0.54, 0.84±0.08) were increased than those in the healthy control group (1.00±0.00, 0.57±0.07) (all P<0.01). Compared with the COPD group, the expressions of mRNA and protein of PI3Kδ in the COPD IC87114 group (1.52±0.28, 0.66±0.13) were decreased (all P<0.01). The RhoA mRNA, protein and activity in the COPD group (0.70±0.07, 0.41±0.10, 0.70±0.06) were decreased compared to those in the healthy control group (1.00±0.00, 0.56±0.09, 1.19±0.09) (all P<0.01). Compared with the COPD group, the expression of mRNA, protein and activity of RhoA in the COPD IC87114 group(0.91±0.08, 0.48±0.06, 0.86±0.06) were increased (P<0.01, P<0.05). Cytoskeleton of AM: The pseudopods of the healthy control group and the healthy IC87114 group extended well, and the ability of phagocytosing FITC-E.coli was intact, but there were some defects in the COPD group. Compared with the COPD group, the COPD IC87114 group was better, both in phagocytosing and extending of pseudopods. Negative correlations existed between the mRNA, protein of PI3Kδ with mRNA, protein and activity of RhoA. Negative correlations also existed between the mRNA, protein of PI3Kδ with MFI, but positive correlations between RhoA and MFI were observed in all groups. Conclusion: The phagocytosis of AMs in COPD mice was defective, with abnormal rearrangement of the cytoskeleton. PI3Kδ negatively regulated RhoA, while PI3Kδ over activation resulted in decreasing activity of RhoA and then induced abnormal cytoskeleton rearrangement in AMs, which led to phagocytosis deficiency.IC87114 inhibited PI3Kδ activation, improved the activity of RhoA and partly recovered phagocytosis of AMs.

[Mechanisms of cytoskeleton and PI3Kδ-RhoA in fine particulate matter deteriorating phagocytosis defect of alveolar macrophage in mice with chronic obstructive pulmonary disease]

Objective: To explore the mechanism of cytoskeleton and PI3Kδ-RhoA in fine particulate matter deteriorating phagocytosis defect of alveolar macrophage (AM) in chronic obstructive pulmonary disease (COPD) mice. Methods: Forty mice were randomly divided into four groups: health control group, COPD group, health PM2.5 group, COPD PM2.5 group and with ten in each group. A mouse model of COPD was established by cigarette smoke exposure, and health PM2.5 group and COPD PM2.5 group mice were given PM2.5 (588 μg/m(3)) aerosol inhalation for 90 days. AM were isolated from lung tissue by discontinuous density gradient centrifugation. Mean fluorescence intensity (MFI) and the percent of alveolar macrophage engulfing flurescein isothiocyanate-labeled Escherichia coli (FITC-E.coli) AM (AM%) were detected by flow cytometry. The mRNA and protein expression were measured by real time polymerase chain reaction (RT-PCR) and Western blot. The activity of RhoA was measured by GTPase linked immunosorbent assay (G-LISA) Kit. Cytoskeleton was observed by laser scanning confocal microscopy. Results: The MFI and the AM% in COPD group [4 512±517, (32.19±4.57)%] and health PM2.5 group [7 631±585, (50.78±4.58)%] were significantly lower than those in health control group [9 857±1 042, (68.53±2.88)%], while those in COPD PM2.5 group [3 121±393, (21.90±2.58)%] were lower than those in COPD group (all P<0.01). The mRNA and protein of PI3Kδ in COPD group (3.41±0.54, 0.84±0.08)and health PM2.5 group (1.52±0.35, 0.71±0.11) were higher than those in health control group (1.00±0.00, 0.57±0.07) (all P<0.05), and in COPD PM2.5 group (5.53±0.42, 1.17±0.25), the above parameters were remarkably increased as compared to those in COPD group (all P<0.01). The mRNA, protein and activity of RhoA in COPD group (0.70±0.07, 0.41±0.10, 0.70±0.06) and health PM2.5 group (0.84±0.06, 0.46±0.11, 0.87±0.07) were lower than those in health control group (1.00±0.00, 0.56±0.09, 1.19±0.09) (all P<0.05), and above parameters of COPD PM2.5 group (0.42±0.05, 0.31±0.06, 0.44±0.04) were significantly lower than COPD group (all P<0.01). Cytoskeleton of AM: long and dense filopodia and membrane fold could been seen clearly around the AM of health control group; in COPD group and health PM2.5 group, short and sparse filopodia and slightly deformed AM can been seen. Filopodia remarkably decreased and rigid cells with impaired capacity of engulfing FITC-E.coli can be generally observed in COPD PM2.5 group. Negative correlations were existed between PI3Kδ mRNA, protein and RhoA mRNA, protein, activity in all groups (all P<0.01). Negative correlations were existed between PI3Kδ mRNA, protein and MFI, and positive correlations were existed between RhoA mRNA, protein, activity and MFI in all groups (all P<0.05). Conclusion: Fine particulate matter (PM2.5) can deteriorate the phagocytosis of AM from COPD mice through over activating PI3Kδ and inhibiting the activity of RhoA then causing cytoskeleton abnormal rearrangement.

Genetic diversity of mtDNA D-loop sequences in four native Chinese chicken breeds

1. To explore the genetic diversity of Chinese indigenous chicken breeds, a 585 bp fragment of the mitochondrial DNA (mtDNA) region was sequenced in 102 birds from the Xichuan black-bone chicken, Yunyang black-bone chicken and Lushi chicken. In addition, 30 mtDNA D-loop sequences of Silkie fowls were downloaded from NCBI. The mtDNA D-loop sequence polymorphism and maternal origin of 4 chicken breeds were analysed in this study. 2. The results showed that a total of 33 mutation sites and 28 haplotypes were detected in the 4 chicken breeds. The haplotype diversity and nucleotide diversity of these 4 native breeds were 0.916 ± 0.014 and 0.012 ± 0.002, respectively. Three clusters were formed in 4 Chinese native chickens and 12 reference breeds. Both the Xichuan black-bone chicken and Yunyang black-bone chicken were grouped into one cluster. Four haplogroups (A, B, C and E) emerged in the median-joining network in these breeds. 3. It was concluded that these 4 Chinese chicken breeds had high genetic diversity. The phylogenetic tree and median network profiles showed that Chinese native chickens and its neighbouring countries had at least two maternal origins, one from Yunnan, China and another from Southeast Asia or its surrounding area.

[Surgical reconstruction of maxillary defects using a computer-assisted techniques]

The maxilla is the most important bony support of the mid-face skeleton and is critical for both esthetics and function. Maxillary defects, resulting from tumor resection, can cause severe functional and cosmetic deformities. Furthermore, maxillary reconstruction presents a great challenge for oral and maxillofacial surgeons. Nowadays, vascularized composite bone flap transfer has been widely used for functional maxillary reconstruction. In the last decade, we have performed a comprehensive research on functional maxillary reconstruction with free fibula flap and reported excellent functional and acceptable esthetic results. However, this experience based clinical procedure still remainssome problems in accuracy and efficiency. In recent years, computer assisted techniques are now widely used in oral and maxillofacial surgery. We have performed a series of study on maxillary reconstruction with computer assisted techniques. The computer assisted techniques used for maxillary reconstruction mainly include: (1) Three dimensional (3D) reconstruction and tumor mapping: providing a 3D view of maxillary tumor and adjacent structures and helping to make the diagnosis of maxillary tumor accurate and objective; (2) Virtual planning: simulating tumor resection and maxillectomy as well as fibula reconstruction on the computer, so that to make an ideal surgical plan; (3) 3D printing: producing a 3D stereo model for prebending individualized titanium mesh and also providing template or cutting guide for the surgery; (4) Surgical navigation: the bridge between virtual plan and real surgery, confirming the virtual plan during the surgery and guarantee the accuracy; (5) Computer assisted analyzing and evaluating: making a quantitative and objective of the final result and evaluating the outcome. We also performed a series of studies to evaluate the application of computer assisted techniques used for maxillary reconstruction, including: (1) 3D tumor mapping technique for accurate diagnosis and treatment of maxillary tumor; (2) Maxillary reconstruction with free fibula flap used computer assisted techniques; (3) Computer assisted orbital floor reconstruction after maxillectomy. The results suggested that computer assisted techniques could significantly improve the clinical outcome of maxillary reconstruction.

The antitumor efficacy of anti-p21Ras scFv mediated by the dual-promoter-regulated recombinant adenovirus KGHV300

Ras mutations and overexpression of the Ras protein, p21Ras, are main causes of cancer development and progression, which has made the Ras gene and p21Ras important targets for therapy of Ras-driven cancers. We previously prepared recombinant adenovirus KGHV100 based on replication-defective adenovirus type 5, which could intracellularly express anti-p21Ras single chain fragment viable antibodies (scFv) and repress tumor growth in vitro and in vivo. However, the anti-tumor effects of this anti-p21Ras scFv were limited by short-term scFv expression due to a replication defect of KGHV100. To enhance the anti-tumor efficacy and safety of anti-p21Ras scFv, the present study constructed a dual-promoter-regulated recombinant adenovirus KGHV300 that carried anti-p21Ras scFv. In KGHV300, the expression levels of the essential replication genes E1a and E1b, were controlled by the human telomerase reverse transcriptase promoter and the hypoxia response element, respectively, and the anti-p21Ras scFv gene was controlled by the cytomegalovirus promoter. The conditional replication of KGHV300 and its antitumor efficacy were characterized in several tumor cell lines in vitro and in xenograft models of human breast cancer in nude mice. TCID50 assay demonstrated that KGHV300 could replicate in tumor cell lines but not in normal cell lines. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay indicated that the growth of tumor cells was effectively inhibited by KGHV300 infection. In MDA-MB-231 tumor xenograft models, KGHV300 effectively and significantly inhibited tumor growth and induced apoptosis of tumor cells. We concluded that the recombinant adenovirus KGHV300 may be a more potent and safer antitumor therapeutic for Ras-driven cancer biotherapy.

[Effects of mTOR-Cdc42 signaling pathway on phagocytosis of alveolar macrophages in chronic obstructive pulmonary disease mice]

Objective: To investigate effects of mammalian target of rapamycin (mTOR)- cell division cycle 42 (Cdc42) signaling pathway on phagocytosis of alveolar macrophages (AMs) in chronic obstructive pulmonary disease (COPD) mice. Methods: Forty mice were randomly divided into control group and model group. Each group contained 20 mice. COPD model group were established by cigarette smoking exposure. AMs were isolated from lung tissue by discontinuous density gradient centrifugation. AMs from control group were divided into health control group and rapamycin control group while AMs from model group were divided into COPD group and rapamycin COPD group. The AMs from rapamycin control group and rapamycin COPD group were incubated with a final concentration of 10 nmol/L rapamycin for 24 hours. Mean fluorescence intensity (MFI) and the positive percent of alveolar macrophage engulfed flurescein isothiocyanate-labeled Escherichina coli (FITC-E.coli) AM (AM%) were detected by flow cytometry. Real time PCR (RT-PCR) and Western blot were applied to detect mRNA and protein. The activity of Cdc42 was detected by G-LISA Small GTPase Activation Assays (G-LISA) Cdc42 Kit. The cytoskeleton structure of AM was observed by laser scanning confocal microscopy. Results: MFI and AM% in COPD group were decreased than those in health control group[4 060±590 vs 9 190±988 and (28.65±1.26)% vs (67.50±4.56)%]; Compared with COPD group, MFI and AM% in rapamycin COPD group[4 856±762, (38.31±1.71)%]were increased (all P<0.05). The expression of mRNA, protein and activity of mTOR in COPD group were increased than those in health control group[(2.62±0.46, 1.30±0.52, 1.46±0.43) vs (1.00±0.00, 0.48±0.27, 0.58±0.26)]; compared with COPD group, the expression of mRNA, protein and activity of mTOR in rapamycin COPD group (1.40±0.36, 0.90±0.66, 0.92±0.28) were decreased (all P<0.05). The Cdc42 mRNA, protein and activity in COPD group were higher than those in health control group[(2.56±0.50, 1.61±0.37, 0.46±0.09) vs (1.00±0.00, 0.67±0.22, 0.30±0.07)](all P<0.01); compared with COPD group, the expression of mRNA, protein and activity of Cdc42 in rapamycin COPD group (1.38±0.34, 0.91±0.48, 0.36±0.06) were decreased (all P<0.01). Filopodia protruding can not be seen in the cytoskeleton of AMs from health control group and rapamycin control group; some filopodia protruding can be seen in AM from COPD group; some long filopodia protruding can be seen in AM from rapamycin COPD group. Negative correlations were existed between the mRNA, protein and activity of mTOR, Cdc42 and MFI in all group. Conclusions: mTOR-Cdc42 signaling pathway is activated and related to phagocytosis deficiency of AM in COPD. It can be inferred that the pathway is involved in the pathogenesis of COPD.

Comparative analysis of shell color variety and genetic structure among five high-quality freshwater pearl mussel populations

Four Hyriopsis cumingii populations, a breeding population (BP), a cultured population (FP), two wild populations from Poyang Lake (PY) and Dongting Lake (DT), and an H. schlegelii population were collected (JX), and the first filial generations (F1) were bred synchronously. The shell nacre polymorphisms, population genetic diversity, and genetic structures of the F1 of each population were analyzed and compared using CIELAB colorimetric measurements and microsatellite markers. The color parameters of the shell nacre (L*, a*, dE*) in the BP were significantly different from those in the FP, PY, and JX populations (P < 0.05), whereas the shell nacre color did not differ significantly between the left and right sides of the shells within the same population (P > 0.05). The BP had relatively darker nacre at the posterior end of the shell, and the color parameters (L*, a*, b*, and dE*) differed significantly from those at the front end (P < 0.05). The five populations showed relatively high levels of genetic diversity (H_O = 0.733-0.829). The genetic distance between the H. cumingii populations and H. schlegelii was the greatest, whereas that within the H. cumingii populations and between the FP and the PY population was the smallest. All the individuals tested in this study were optimally grouped into four theoretical populations. In conclusion, the BP was significantly different from the base populations of PY and DT in terms of genetic background and phenotypic parameters of shell nacre color, with potential for further genetic improvement.

[The application of conscious sedation with a small dose of dexmedetomidine and sufentanil in elderly patients undergoing multiple intestinal polyps resection]

Objective: To explore the effectiveness and feasibility of conscious sedation with a low dose of dexmedetomidine and sufentanil during multiple intestinal polyps resection in elderly patients. Methods: Sixty elderly patients who underwent multiple intestinal polyps resection in Peking University Third Hospital from Janurary to May 2016 were randomly divided into dexmedetomidine group (D group, n=30) and propofol group (P group, n=30). There were 28 males and 32 females with a mean age of (70.4±4.5) years old (range: 65-80 years old). The patients in the dexmedetomidine group received a loading dose of 0.3 μg/kg followed by a continuous infusion of 0.2-0.4 μg·kg^-1·min^-1 of dexmedetomidine and sufentanil (0.1 μg/kg) respectively.The patients in the propofol group received sufentanil 0.1 μg/kg and propofol 1.5 mg/kg and followed by a continuous infusion of 3-6 mg·kg^-1·h^-1 of propofol.Blood pressure, heart rate, pulse oxygen saturation (SpO₂), respiratory rate and bispectral index (BIS) were recorded at the basic status and at the beginning of operation, 10 min, 20 min, 30 min after operation, the end of operation and departure.The observer's assessment of alertness/sedation (OAA/S) scores and the clinical responses were also recorded.A statistical analysis was performed. Results: All patients in the two groups were sedated compared with baseline.The BIS values of patients in group D at beginning of the operation, 10 min, 20 min, 30 min after operation and the end of operation were 89.6(87.8-91.0), 79.4(78.0-80.0), 76.9(75.0-80.0), 76.0(73.0-79.0) and 75.6(70.0-79.0) respectively, and those values were all significantly lower than baseline value[96.4(95.0-98.0)], (Z=-4.645, -4.788, -4.787, -4.789, -4.789, P<0.05). The OAA/S score at beginning of the operation, 10 min, 20 min, 30 min after operation and the end of operation were 4.5(4.0-5.0), 3.4(3.0-4.0), 3.0(3.0-3.0), 3.5(3.0-4.0) and 3.3(3.0-4.0) respectively, and were significantly lower than baseline score [4.8(5.0-5.0)] (Z=-2.828, -4.862, -5.031, -4.420, -4.710, P<0.05). The BIS value of patients in group P at beginning of the operation, 10 min, 20 min, 30 min after operation and the end of operation were 54.7(50.0-59.3), 54.8(50.0-59.3), 50.7(47.8-56.8), 54.4(51.5-58.0) and 53.7(50.0-57.3) respectively, and were significantly lower than baseline value[95.8(95.0-96.3)] (Z=-4.786, -4.787, -4.788, -4.786, -4.786, P<0.05). The OAA/S score at beginning of the operation , 10 min, 20 min, 30 min after operation and the end of operation were 0.4(0.0-1.0), 0.4(0.0-1.0), 0.4(0.0-1.0), 0.4(0.0-1.0) and 0.4(0.0-1.0) respectively, and were significantly lower than baseline score[4.9(5.0-5.0)] (Z=-4.927, -4.901, -4.912, -4.912, -4.901, P<0.05). The sedation state of group D were lighter than group P. The BIS value and OAA/S score at beginning of the operation, 10 min, 20 min, 30 min after operation and the end of operation in group D were higher than group P (P<0.05). The breath and circulation were more stable in group D. The mean arterial pressure, breath rate and SpO₂ at beginning of the operation, 10 min, 20 min, 30 min after operation and the end of operation in group D were higher than group P (P<0.05). There was no oxygen desaturation , hypotension and drowsiness in group D and the incidence in group P were 30.0%, 33.3% and 13.3% respectively.The emergency time and duration of stay in the PACU (post anesthesia care unit) were (2.0±1.2) and (22.0±7.4) min in group D, and they were (4.9±2.4) and (35.8±11.6) min in group P (t=-5.839, t=-5.472, P<0.05). There was no difference in surgery time, patient satisfaction and acceptance rate of reexamination (t=-3.031, t=-7.322, t=2.069, P>0.05). Conclusion: Conscious sedation with dexmedetomidine and sufentanil is effective and feasible in elderly patients undergoing multiple intestinal polyps resection.

[Targeted suppression of miRNA-21 inhibit K562 cells growth through PTEN-PI3K/AKT signaling pathway]

Objective: To investigate the K562 cells biological function and related molecular changes in PTEN-PI3K/AKT signaling pathway of leukemia K562 cells by inhibiting the miRNA-21 expression to explore its pathogenesis of leukemia. Methods: The chemical synthetic miRNA-21 inhibitor was transfered into K562 cells by electrotransfection. RT-PCR was used to detect the miRNA-21 expression changes. Cell proliferation and apoptosis were determined by using MTT and flow cytometry. Western-blot were used to detect the protein expression changes of PTEN, PI3K and p-AKT respectively. Results: The relative expression of miRNA-21 in experimental group was (8.070 ± 5.138)% at 24 hours, which was lower than control groups (P<0.05). The apoptotic rate of (13.370±0.250)% at 24 hours in experimental group was obviously higher than control groups. The cellular proliferation were significantly different at 24 hours. The proliferation inhibition rate was (8.1±0.9)% at 24 hours, which was up to (43.1±2.1)% at 60 hours, but the control groups showed no difference. K562 cell proliferation significantly decreased, while cell apoptosis markedly increased by inhibiting miRNA-21 expression (P<0.01). Western-blot analysis revealed up-regulation of PTEN and down-regulation of PI3K and p-AKT protein expressions after successfully suppressed miRNA-21 expression (P<0.01). Conclusion: Inhibiting miRNA-21 expression in K562 cell could suppress the PI3K/AKT pathway by up-regulation of PTEN expression and promote cell antiproliferative and pro-apoptosis effects.

[Evaluation of therapeutic effect of virtual design for correcting facial asymmetry of skeletal Class Ⅲ deformity]

Objective: To establish a computer-aided surgical simulation procedure based on the natural head position(NHP) for orthognathic surgery and to access the effect for correcting facial asymmetry for skeletal Class Ⅲ deformity. Methods: Thirty-five patients(male: 14 and female: 21, mean age: [21.5±2.3] years) of skeletal Class Ⅲ deformity with facial asymmetry were included and divided into virtual group (16 patients) and control group(19 patients). The computer-aided surgical simulation procedure was used in the virtual group and the intermediate and final splints were fabricated using the rapid protyping technique. The traditional model surgery based on plaster casts was used in control group, and the splints were handmade. To evaluate the symmetry, three-dimensional(3D) photos were taken for all the patients before operation and 6 months after operation using the 3dMD face imaging system. Coordinate system was built based on mirror-original alignment method on the 3D photo. Thirteen soft tissue landmarks were marked on each 3D photo. The asymmetry index(AI) of those soft tissue landmarks was calculated. Results: There was no significant difference in the AI values between the two groups before surgery. Sixth month after operation, the mean AI values in the virtual group were (0.81±0.50) mm for subnasale, (1.01±0.80) mm for labiale superius, (1.94±1.30) mm for crista philtri, (1.60±1.20) mm for pogonion and (5.68±2.25) mm for gonion. The mean AI values in the control group were (1.49±1.10) mm for subnasale, (1.79±1.33) mm for labiale superius, (3.52±2.50) mm for crista philtri, (2.79±2.08) mm for pogonion and (8.43±3.94) mm for gonion and those indexes were significantly different between the two groups(P<0.05). There was no significant difference in the AI values of the pronasale, alare, labiale inferius and cheilion between the two groups sixth month after operation. Conclusions: The introduced procedure of the virtual design based on the estimated NHP could more effectively correct the asymmetry deformity for the skeletal Class Ⅲ patients.

[Oxymatrine inhibits target cell infection in the HCVcc system]

OBJECTIVE

To validate the antiviral effect of oxymatrine against hepatitis C virus (HCV) in the construction of the cell culture-based infectious virus system HCVcc.

METHODS

An HCVcc system was established by infecting Huh7.5.1 cells with the J6 adapted virus (J6cc). Cells of the HCVcc system were then treated with different concentrations of oxymatrine for 24 h, 48 h and 72 h, or left untreated (controls). MTT assay was used to detect effects on proliferation. Real-time quantitative PCR was used to detect effects on HCV mRNA expression level, and immunofluorescence was used to detect effects on HCV protein expression. Data were expressed as mean±standard deviation, and statistically assessed using one-way ANOVA and one-sample t-test.

RESULTS

Treatment with 2, 4, 8 and 12 mg/mL of oxymatrine for 24 h inhibited proliferation of the J6cc-infected cells by 8.4%, 15.2%, 29.6% and 48.6% respectively, 48 h treatment inhibited by 14.3%, 25.7%, 46.1% and 66.4% respectively, and 72 h treatment inhibited by 36.5%, 46.6%, 70.6% and 85.4% respectively. Thus, the effects of oxymatrine were time- and dose-dependent (P < 0.05). The mRNA expression level in the oxymatrine-treated cells of the HCVcc system was 0.59 ± 0.12, which was significantly lower than that in the control cells (P < 0.05). Moreover, as the oxymatrine concentration increased from 2 mg/mL to 12 mg/mL, the expression levels of HCV proteins also showed a decreasing trend.

CONCLUSION

We successfully constructed a J6cc infection HCVcc system and verified the antiviral effect of oxymatrine against HCV.

[Effect of PM2.5 on the level of nuclear factor erythroid-2 related factor 2 in chronic obstructive pulmonary disease mice and its relationship with oxidative stress]

OBJECTIVE

To explore the effects of fine particulate matter on the level of nuclear factor erythroid-2 related factor 2 (Nrf2) in pulmonary tissues of chronic obstructive pulmonary disease (COPD) mouse models and its relationship with oxidative stress.

METHODS

Totally 40 BALB/c mice were randomly divided into normal control group, normal PM2.5 group, COPD control group and COPD PM2.5 group.COPD mice were established using exposure of cigarette smoking.PM2.5 (20 mg/kg) was intratracheally instilled in PM2.5 group mice.Mice pulmonary function was measured by mice noninvasive body plethysmograph and lung histopathology was observed in normal control group and normal PM2.5 group mice.The mRNA and protein expression of Nrf2 was measured with real-time polymerase chain reaction (PCR) and Western blot methods.Total antioxidative capacity (TAC) was measured by O-phenanthroline colorimetry.Glutathione peroxidase (GSH-PX) was measured by improved Hafeman colorimetry and malondialdehyde (MDA) by thiobarbiturieacid colorimetry.

RESULTS

Nrf2 mRNA and protein in normal control group, normal PM2.5 group, COPD control group and COPD PM2.5 group were 1.00, 4.46±0.42, 4.93±0.63, 6.41±0.35 and 0.92±0.08, 1.23±0.07, 1.20±0.09, 1.43±0.10.Nrf2 mRNA and protein in COPD control group were increased than those in normal control group while those in normal PM2.5 group and COPD PM2.5 group were respectively higher than each control group.Comparing to normal PM2.5 group, the Nrf2 mRNA and protein in COPD PM2.5 group were increased (all P<0.01). TAC and GSH-PX in each group were (5.1±0.4), (2.9±0.4), (3.3±0.3), (1.8±0.3) and (13.4±0.5), (9.9±0.7), (9.8±0.7), (7.0±0.6) U/mgpro.TAC and GSH-PX in COPD control group were decreased than those in normal control group while those in normal PM2.5 group and COPD PM2.5 group were respectively lower than each control group.Comparing to normal PM2.5 group, the Nrf2 mRNA and protein in COPD PM2.5 group were decreased (all P<0.01). MDA in each group were (2.9±0.4), (4.8±0.5), (4.5±0.3), and (6.2±0.4) nmol/mgpro.MDA in COPD control group were increased than those in normal control group while those in normal PM2.5 group and COPD PM2.5 group were respectively higher than each control group.Comparing to normal PM2.5 group, the MDA in COPD PM2.5 group were increased (all P<0.01). Positive correlations were observed between Nrf2 mRNA, protein and MDA, while negative correlations were observed between Nrf2 mRNA, protein and TAC, GSH-PX in all groups (all P<0.05).

CONCLUSIONS

PM2.5 can induce Nrf2 expression and aggravate oxidative stress in COPD mice.The increased expression of Nrf2 is closely associated with oxidative stress.

Microarray analysis of microRNA deregulation and angiogenesis-related proteins in endometriosis

We examined the aberrant microRNA (miRNA) expression profile responsible for the changes in angiogenesis observed in endometriotic lesions. This study revealed characteristic miRNA expression profiles associated with endometriosis in endometrial tissue and endometriotic lesions from the same patient, and their correlation with the most important angiogenic and fibrinolytic factors. miRNA expression was quantified using a microRNA array and reverse-transcription microRNA polymerase chain reaction. Levels of vascular endothelial growth factor A (VEGFA), epidermal growth factor receptor 2 (EGFR2), phosphatase and tensin homolog (PTEN), and C-X-C chemokine receptor type 4 (CXCR4) were quantified using enzyme-linked immunosorbent assay. The endometrial tissue showed significantly lower levels of miR-200b, miR-15a-5p, miR-19b-1-5p, miR-146a-5p, and miR-200c, and higher levels of miR-16-5p, miR-106b-5p, and miR-145-5p. VEGFA was significantly upregulated, whereas EGFR2, PTEN, and CXCR4 were markedly downregulated, in the endometriotic tissues compared to that in the normal endometrial tissues. In conclusion, differences in the miRNA levels could modulate the expression of VEGFA, EGFR2, PTEN, and CXCR4, and may play an important role in the pathogenesis of endometriosis. The higher angiogenic and proteolytic activities observed in the eutopic endometrium might facilitate the implantation of endometrial cells at ectopic sites.

[3.0 T MR diffusion tentor imaging in the differential diagnosis of breast mass lesions]

OBJECTIVE

To investigate the differential diagnostic value of DTI parameters in breast mass lesions by comparing apparent diffusion coefficient (ADC), fractional aniotropy (FA) and maximum eigenvalue (λ1)of normal glandular tissue, benign lesions and malignant lesions.

METHODS

A total of 71 women patients with 74 mass lesions between December 2013 and October 2015 were enrolled from Beijing Chao-Yang Hospital.MRI protocol included dynamic contrast-enhanced MRI (DCE-MRI)and diffusion tentor imaging(DTI) were executed.The ADC, λ1 and FA of lesions and normal glandular tissue were calculated.The ADC, λ1 and FA of lesions were compared by paired t test between the benign/malignant tumors and the contratlateral healthy breast tissue.ROC curve analysis was performed to compare diagnostic performance based on the area under the curve(AUC). The sensitivity and specificity of the DCE-MRI combined with ADC and DCE-MRI combined with λ1 were calculated.

RESULTS

The ADC, FA and λ1 values of malignant lesions were (1.09±0.18)×10(-3) mm(2)/s, 0.22±0.02 and(0.97±0.19)×10(-3) mm(2)/s , these values of benign lesions were (1.52±0.19)×10(-3) mm(2)/s, 0.21±0.02 and(1.79±0.19)×10(-3) mm(2)/s, there were statistically significant differences (all P<0.05). Area under the curve of ADC, FA and λ1 were 0.990, 0.605 and 0.978, respectively. The AUC of FA was lower than that of ADC and λ1(P<0.01, <0.01), but there was no difference between the AUC of ADC and that of λ1(P=0.131 6). The sensitivity DCE-MRI combined with ADC and DCE-MRI combined with λ1 was 88.6% vs 97.1%(P=0.353 3), the specificity was 84.6% vs 97.4%(P=0.113 0).

CONCLUSION

ADC and λ1 is helpful to differentiate malignant from benign in mass lesions.

[Effect of bufalin on proliferation and apoptosis through ERK/RSK2 pathway in human esophageal carcinoma cell line xenografts in nude mice]

OBJECTIVE

To investigate the effect of bufalin on proliferation and apoptosis through ERK/RSK2 pathway in esophageal squamous cell carcinoma xenografts in nude mice.

METHODS

The subcutaneous xenograft model of esophageal cancer ECA109 cells in nude mice was established. The mice were divided into the model group, low-dose bufalin group, medium-dose bufalin group, high-dose bufalin group, PD98059 group and combination group to evaluate the effect of bufalin on the xenografts. The morphology of xenografts was observed by microscopy. The cell apoptosis index of xenografts was detected by TUNEL assay. The expression of ERK and RSK2 mRNA of human ECA109 cell transplantation tumor in nude mice was examined by real-time quantitative PCR. The protein levels of ERK, p-ERK, RSK2, p-RSK2, GSK3β, p-GSK3β, Bad and p-Bad in the xenografts were examined by Western blot and Immunohistochemistry.

RESULTS

The tumor size of nude mice in the model group, low-dose bufalin group (BL), medium -dose bufalin group (BM), high-dose bufalin group (BH), PD98059 group and combined therapy group (BP) was (1.758±0.181) cm(3,) (1.680±0.150) cm(3,) (1.285±0.134) cm(3,) (0.873±0.095) cm(3,) (0.815±0.108) cm(3) and (0.530±0.104) cm(3,) respectively. Histological examination showed that the xenografts of each group had varying degrees of necrosis, and the most extensive necrosis was observed in the BP group. The TUNEL assay showed that the cell apoptosis index of xenografts in the model, BL, BM, BH, PD98059 and BP groups was (6.0±0.6)%, (11.0±0.7)%, (19.1±0.9)%, (25.1±1.4)%, (20.0±1.2)% and (17.1±0.7)%, respectively, which is highest in the BH group. The real-time quantitative PCR results showed that the ΔCT values of ERK mRNA in the model, BL, BM, BH, PD98059 and BP groups were 0.270±0.084, 0.293±0.081, 0.596±0.224, 0.857±0.183, 0.868±0.187 and 1.313±0.282, respectively. The ΔCT values of RSK2 mRNA in the model, BL, BM, BH, PD98059 and BP groups were 0.340±0.062, 0.337±0.071, 0.642±0.226, 0.915±0.170, 0.923±0.176 and 1.413±0.269, respectively. The relative expression of ERK and RSK2 mRNA was gradually decreased. Western blot and immunohistochemistry results showed that the protein levels of ERK, RSK2 and Bad in each group were not significantly different (P>0.05). The protein levels of p-ERK in the model, BL, BM, BH, PD98059 and BP groups were 0.721±0.094, 0.695±0.095, 0.555±0.080, 0.388±0.052, 0.341±0.060, 0.235± 0.056, respectively. The median immunoreactivity scores of p-ERK in each group were 8, 8, 6, 4, 5 and 3. The protein levels of p-RSK2 in the model, BL, BM, BH, PD98059 and BP groups were 0.613±0.085, 0.612±0.084, 0.427±0.089, 0.305±0.056, 0.258±0.051, 0.158±0.058, respectively. The median immunoreactivity scores of p-RSK in each group were 8, 8, 5, 3, 3 and 1. The protein level of GSK3β in the model, BL, BM, BH, PD98059 and BP groups were increased gradually, while the protein level of p-GSK3β and p-Bad were decreased gradually.

CONCLUSIONS

Bufalin exerts significant inhibitory effect on the esophageal squamous cell carcinoma xenogragts in nude mice. Bufalin may suppress the growth of xenogragts in nude mice by down-regulating the level of ERK and RSK2 phosphorylation, inhibit the proliferation of xenogragts via inactivating GSK3β and promote apoptosis through down-regulation of p-Bad.

[Inhibitory effects of codonopsis pilosula polysaccharides on the deterioration of impaired phagocytosis of alveolar macrophage induced by fine particulate matter in chronic obstructive pulmonary disease mice]

OBJECTIVE

To investigate the inhibitory effects of codonopsis pilosula polysaccharides (CPP) on the deterioration of impaired phagocytosis of alveolar macrophage (AM) induced by fine particulate matter with a mean aerodynamic diameter ≤2.5 μm (PM2.5) in chronic obstructive pulmonary disease (COPD) mice.

METHODS

Sixty BALB/c male mice were randomly divided into control group, COPD group, PM2.5 group, PM2.5 COPD group, CPP COPD group and CPP+ PM2.5 COPD group. COPD mice were established using exposure of cigarette smoking. Meanwhile PM2.5 group, PM2.5 COPD group and CPP+ PM2.5 COPD group were exposed to PM2.5 (770 μg/m(3)) for 90 days. CPP COPD group and CPP+ PM2.5 COPD group were fed with CPP (300 mg/kg) for 90 days whilst other groups were fed with isovolumetric saline. After the models were established, mice peak inspiratory flow (PIF) and peak expiratory flow (PEF) were measured by noninvasive body plethysmograph and lung histopathology and mean linear intercept (MLI) were observed. AMs were isolated from lung tissue by discontinuous density gradient centrifugation. Mean fluorescence intensity (MFI) and the ability of AM phagocytosing flurescein isothiocyanate-labeled Escherichia coli (FITC-E.coli) (AM%) were detected by flow cytometry. Total antioxidative capacity (TAC) was measured by O-phenanthroline colorimetry. Malondialdehyde (MDA) was measured by thiobarbiturieacid colorimetry and glutathione peroxidase (GSH-PX) by improved Hafeman colorimetry.

RESULTS

MFI in control group, COPD group, PM2.5 group, PM2.5 COPD group, CPP COPD group and CPP+ PM2.5 COPD group were 10 267±1 358, 4 817±399, 8 469±240, 3 176±501, 5 886±516 and 4 067±453. AM% in each group were (69.0±5.4)%, (30.7±3.0)%, (51.5±2.4)%, (20.4±3.5)%, (38.7±2.6)% and (28.7±4.3)%. MFI and AM% in COPD group and PM2.5 group were decreased than those in control group while those in PM2.5 COPD group were lower than in COPD group (all P<0.01). Comparing to COPD group and PM2.5 COPD group respectively, MFI and AM% in CPP COPD group and CPP + PM2.5 COPD group were increased (all P<0.01). TAC and GSH-PX in each group were (17.99±0.09), (6.83±0.36), (13.84±1.12), (3.61±0.29), (8.80±0.26), (5.43±0.30) U/mg protein and (84.3±5.7), (46.5±2.6), (62.0±2.2), (32.4±3.8), (53.4±4.0), (42.4±4.0) U/mg. TAC and GSH-PX in COPD group and PM2.5 group were lower than those from control group while those from PM2.5 COPD group were decreased than in COPD group (all P<0.01). Comparing to COPD group and PM2.5 COPD group, TAC and GSH-PX in CPP COPD group and CPP+ PM2.5 COPD group were increased respectively (all P<0.01). MDA in each group were (1.74±0.37), (2.73±0.22), (2.01±0.13), (3.55±0.33), (2.22±0.28) and (2.72±0.44) nmol/mg protein. MDA in COPD group and PM2.5 group were higher than that from control group while that from PM2.5 COPD group was higher than in COPD group; MDA in CPP COPD group and CPP+ PM2.5 COPD group were respectively decreased than those in COPD group and PM2.5 COPD group (all P<0.05). Positive correlations were existed between MFI, AM% and TAC, GSH-PX, while negative correlations were existed between MFI, AM% and MDA in COPD group, PM2.5 group, PM2.5 COPD group, CPP COPD group and CPP+ PM2.5 COPD group.

CONCLUSIONS

PM2.5 further impaired the defective phagocytosing capacity of AM and exacerbated oxidative stress in COPD mice. CPP can inhibit these effects. The protection of CPP may be closely related to its antioxidative effects.

Abnormal correlation between phase transformation and cooling rate for pure metals

This work aims to achieve deep insight into the phenomenon of phase transformation upon rapid cooling in metal systems and reveal the physical meaning of scatter in the time taken to reach crystallization. The total number of pure metals considered in this work accounts for 14. Taking pure copper as an example, the correlation between phase selection of crystal or glass and cooling rate was investigated using molecular dynamic simulations. The obtained results demonstrate that there exists a cooling rate region of 6.3 × 10¹¹–16.6 × 10¹¹ K/s, in which crystalline fractions largely fluctuate along with cooling rates. Glass transformation in this cooling rate region is determined by atomic structure fluctuation, which is controlled by thermodynamic factors. According to the feature of bond-orientation order at different cooling rates, we propose two mechanisms of glass formation: (i) kinetic retardation of atom rearrangement or structural relaxation at a high cooling rate; and (ii) competition of icosahedral order against crystal order near the critical cooling rate.

Early enteral and parenteral nutrition on immune functions of neurocritically ill patients

This study was designed to investigate the influence of early enteral and parenteral nutrition on immune functions of neurocritically ill patients. Patients who were admitted to the neurological intensive care unit (ICU) of The Second Affiliated Hospital of Zhengzhou University between May 2014 and January 2016 were selected. They had been hospitalized for more than one week and received enteral nutrition (EN) via nasogastric tube, with a gross energy of 25 kcal/(Kg • d). Patients were divided into EN group, EN + early PN (EPN) group and EN + supplemental PN (SPN) group according to the time of PN support. Differences in patients’ general information and changes in serum protein and immune indexes were compared between the three groups. On admission, patients’ Glasgow coma scale (GCS), age, immune functions and protein indexes had no obvious differences between the three groups. After nutritional support, serum protein level reduced in the EN group while prealbumin (PALB) and retinol binding protein (RBP) increased in the EN + EPN group and EN + SPN group after one week of admission to hospital, and the differences were statistically significant (p less than 0.05). Total protein (TP), albumin (ALB), PALB and transferrin (TRF) increased significantly in the EN + EPN group and EN + SPN group compared with the EN group (p < 0.05); before and after treatment, an increase was found in ALB in the EN + EPN group in comparison with EN + SPN group, with a notable difference (p < 0.05); C3, C4, immunoglobulin M (IgM) and immunoglobulin A (IgA) increased in the EN + SPN group after nutritional support compared with before treatment, and the difference was statistically significant (p < 0.05). Moreover, immunoglobulin G (IgG) and IgA in the EN + EPN group increased after nutritional support comparing to prior to nutritional support, and the difference was statistically significant (p < 0.05). After nutritional treatment, IgA and IgG increased markedly in the EN + EPN group, and there was a statistical significance between the groups (p < 0.05); the EN + EPN group and EN + SPN group exceeded the EN group in total lymphocyte count (TLC), and the difference had a statistical significance (p less than 0.05). These results demonstrate that neurocritically ill patients achieving the target energy can avoid malnutrition and immunodeficiency; serum protein decrease can cause malnutrition after one week of EN support; and enteral and parenteral nutrition can improve nutritional and immune indicators of neurocritically ill patients in the acute phase. In addition, EPN is more likely to improve malnutrition and immune functions of critical patients than SPN.

Correlation between magnetic resonance perfusion weighted imaging of radiation brain injury and pathology

We used magnetic resonance perfusion weighted imaging and pathological evaluation to examine different stages of radiation-induced brain injury and to investigate the correlation between the relative cerebral blood volume (rCBV) ratio and vascular endothelial growth factor (VEGF). Thirty adult rats were randomly divided into 2 groups: control and radiation group. The control group was not subjected to irradiation. The irradiation group rats were examined by magnetic resonance imaging and magnetic resonance perfusion weighted imaging at 1, 3, 6, 9, and 12 months after radiation treatment. We measured the rCBV, mean transit time, and time to peak. Hematoxylin and eosin staining, immunohistochemical staining, and electron microscopy were performed. VEGF absorbance was evaluated by immunohistochemical staining. Compared with the control group, the differences in rCBV, mean transit time, time to peak, and VEGF absorbance after 3 months were statistically significant (P < 0.05). rCBV was positively correlated with VEGF (r = 0.94, P < 0.05). Magnetic resonance perfusion weighted imaging can reflect pathophysiological changes in brain tissue after irradiation. Decreased expression of VEGF plays a critical role in the pathogenesis of radiation-induced brain injury.

Analysis of an "off-ladder" allele at the Penta D short tandem repeat locus

Kinship testing of a father and his son from Guangxi, China, the location of the Zhuang minority people, was performed using the PowerPlex® 18D System with a short tandem repeat typing kit. The results indicated that both the father and his son had an off-ladder allele at the Penta D locus, with a genetic size larger than that of the maximal standard allelic ladder. To further identify this locus, monogenic amplification, gene cloning, and genetic sequencing were performed. Sequencing analysis demonstrated that the fragment size of the Penta D-OL locus was 469 bp and the core sequence was [AAAGA]21, also called Penta D-21. The rare Penta D-21 allele was found to be distributed among the Zhuang population from the Guangxi Zhuang Autonomous Region of China; therefore, this study improved the range of DNA data available for this locus and enhanced our ability for individual identification of gene loci.

Eosinophil cationic protein mRNA expression in children with bronchial asthma

Studies have shown that eosinophils are closely related to pathogenesis of bronchial asthma. Eosinophils release eosinophil cationic protein (ECP), which plays an important role in infection and allergic reactions. Serum ECP mRNA expression in children with bronchial asthma has not been adequately investigated. We analyzed serum ECP mRNA expression in 63 children with bronchial asthma and 21 healthy children by using reverse-transcriptase polymerase chain reaction to understand the role of ECP in children with bronchial asthma. The children with bronchial asthma were segregated into acute-phase and stable-phase groups, based on the severity of the illness. Serum ECP mRNA expression in children with bronchial asthma (0.375 ± 0.04) was significantly higher than that in healthy controls (0.20 ± 0.02; P < 0.05). Additionally, children in the acute-phase group showed higher ECP mRNA expression level (0.44 ± 0.06) than those in the stable-phase (0.31 ± 0.03) and healthy control groups (0.20 ± 0.02; P < 0.05), while the level in the stable-phase (0.31 ± 0.03) was markedly higher than that in the healthy control group (0.20 ± 0.02; P < 0.05). Detection of serum ECP mRNA expression level has possible applications in the diagnosis and treatment of children with bronchial asthma.

Passively Q-switched Nd:YAG/Cr(4+):YAG bonded crystal microchip laser operating at 1112 nm and its application for second-harmonic generation

A passively Q-switched Nd:YAG/Cr⁴⁺:YAG microchip laser operating at 1112 nm is demonstrated. Under a pump power of 5.5 W, a maximum average output power of 623 mW was obtained with T=6% output coupler, corresponding to an optical-to-optical conversion efficiency of 11.3% and a slope efficiency of 19.5%. The minimum pulse width was 2.8 ns, the pulse energy and peak power were 39.3 μJ and 14 kW, respectively. Additionally, based on the 1112 nm laser, a 230 mW 556 nm green-yellow laser was achieved within an LBO crystal.

Assessment of correlation between pre-miRNA-1757 polymorphism and chicken performance traits

Single nucleotide polymorphism in microRNAs (miRNA) may influence their target gene selection and regulation efficiency, leading to animal phenotypic variation. The aim of this study was to evaluate the possible effect of single nucleotide polymorphisms in the miRNA-1757 gene precursor region (pre-mir-1757) on economic-related traits in chicken. Genotyping was performed using Sequenom MassArray® iPLEX GOLD System. Association analysis was performed using SPSS19.0. The data showed that the G/C polymorphism was significantly correlated with semi-evisceration weight, evisceration weight, carcass weight, body weight at 10 weeks of age, shank length at 4 weeks of age, pectoral angle at 8 weeks of age, and body slanting length and pelvis breadth at 12 weeks of age (P < 0.05), and led to the alteration of the RNA secondary structure of pre-mir-1757. Our results provide useful information for further annotation studies of miRNA function.

Ultra-sparse metasurface for high reflection of low-frequency sound based on artificial Mie resonances

Acoustic metamaterials offer great flexibility for manipulating sound waves and promise unprecedented functionality, ranging from transformation acoustics, super-resolution imaging to acoustic cloaking. However, the design of acoustic metamaterials with exciting functionality remains challenging with traditional approaches using classic acoustic elements such as Helmholtz resonators and membranes. Here we demonstrate an ultraslow-fluid-like particle with intense artificial Mie resonances for low-frequency airborne sound. Eigenstate analysis and effective parameter retrieval show two individual negative bands in the single-size unit cell, one of which exhibits a negative bulk modulus supported by the monopolar Mie resonance, whereas the other exhibits a negative mass density induced by the dipolar Mie resonance. The unique single-negative nature is used to develop an ultra-sparse subwavelength metasurface with high reflectance for low-frequency sound. We demonstrate a 0.15λ-thick, 15%-filling ratio metasurface with an insertion loss over 93.4%. The designed Mie resonators provide diverse routes to construct novel acoustic devices with versatile applications.

Nerve growth factor for the treatment of spinocerebellar ataxia type 3: an open-label study

BACKGROUND

Spinocerebellar ataxia type 3 (SCA3) is the most common subtype of SCA worldwide, and runs a slowly progressive and unremitting disease course. There is currently no curable treatment available. Growing evidence has suggested that nerve growth factor (NGF) may have therapeutic effects in neurodegenerative diseases, and possibly also in SCA3. The objective of this study was to test the efficacy of NGF in SCA3 patients.

METHODS

We performed an open-label prospective study in genetically confirmed adult (>18 years old) SCA3 patients. NGF was administered by intramuscular injection (18 μg once daily) for 28 days consecutively. All the patients were evaluated at baseline and 2 and 4 weeks after treatment using the Chinese version of the scale for assessment and rating of ataxia (SARA).

RESULTS

Twenty-one SCA3 patients (10 men and 11 women, mean age 39.14 ± 7.81 years, mean disease duration 4.14 ± 1.90 years, mean CAG repeats number 77.57 ± 2.27) were enrolled. After 28 days of NGF treatment, the mean total SARA score decreased significantly from a baseline of 8.48 ± 2.40 to 6.30 ± 1.87 (P < 0.001). Subsections SARA scores also showed significant improvements in stance (P = 0.003), speech (P = 0.023), finger chase (P = 0.015), fast alternating hand movements (P = 0.009), and heel-shin slide (P = 0.001).

CONCLUSIONS

Our preliminary data suggest that NGF may be effective in treating patients with SCA3.

Reconstruction of maxillary defects with free fibula flap assisted by computer techniques

OBJECTIVE

Free fibula flaps are widely used for maxillary reconstruction. The three-dimensional position of the fibula flap is very difficult to control in conventional operations based solely on the surgeon's experience. We aimed to improve this surgery by using computerized techniques.

METHODS

Twenty-seven patients with maxillary tumors underwent maxillectomy and free fibula flap reconstruction in our department between 2011 and 2013. Virtual planning and surgical navigation were used for eight patients, and conventional surgery was performed in 19 patients. The three-dimensional fibular positions were evaluated in the two groups. Differences between the postoperative position of the fibular segments and the virtual plans were evaluated in the computer-assisted surgery group.

RESULTS

The three-dimensional position of the fibula flap in the computer-assisted surgery group, including the vertical distance (p = 0.013), horizontal position (p = 0.019) and extension of the posterior end (p = 0.041), was significantly more accurate and nearer to the ideal position than that in the conventional surgery group. The average difference between the actual postoperative position of the fibular segments and the virtual plan in the computer-assisted surgery group was <5 mm.

CONCLUSION

Application of computer-assisted techniques such as virtual planning and surgical navigation significantly improve the clinical outcomes of maxillary reconstruction with free fibula flaps.

Propofol inhibits burn injury-induced hyperpermeability through an apoptotic signal pathway in microvascular endothelial cells

Recent studies have revealed that an intrinsic apoptotic signaling cascade is involved in vascular hyperpermeability and endothelial barrier dysfunction. Propofol (2,6-diisopropylphenol) has also been reported to inhibit apoptotic signaling by regulating mitochondrial permeability transition pore (mPTP) opening and caspase-3 activation. Here, we investigated whether propofol could alleviate burn serum-induced endothelial hyperpermeability through the inhibition of the intrinsic apoptotic signaling cascade. Rat lung microvascular endothelial cells (RLMVECs) were pretreated with propofol at various concentrations, followed by stimulation with burn serum, obtained from burn-injury rats. Monolayer permeability was determined by transendothelial electrical resistance. Mitochondrial release of cytochrome C was measured by ELISA. Bax and Bcl-2 expression and mitochondrial release of second mitochondrial-derived activator of caspases (smac) were detected by Western blotting. Caspase-3 activity was assessed by fluorometric assay; mitochondrial membrane potential (Δψm) was determined with JC-1 (a potential-sensitive fluorescent dye). Intracellular ATP content was assayed using a commercial kit, and reactive oxygen species (ROS) were measured by dichlorodihydrofluorescein diacetate (DCFH-DA). Burn serum significantly increased monolayer permeability (P<0.05), and this effect could be inhibited by propofol (P<0.05). Compared with a sham treatment group, intrinsic apoptotic signaling activation - indicated by Bax overexpression, Bcl-2 downregulation, Δψm reduction, decreased intracellular ATP level, increased cytosolic cytochrome C and smac, and caspase-3 activation - was observed in the vehicle group. Propofol not only attenuated these alterations (P<0.05 for all), but also significantly decreased burn-induced ROS production (P<0.05). Propofol attenuated burn-induced RLMVEC monolayer hyperpermeability by regulating the intrinsic apoptotic signaling pathway.

Multivariate analysis of molecular markers in peripheral blood associated with recurrence and metastasis of hepatocellular carcinoma

Invasion, metastasis, and recurrence are the most common causes of death in patients with hepatocellular carcinoma (HCC) and are therefore critical factors for both therapy and prognosis. Current methods for diagnosis of HCC rely mainly on serological markers such as alpha-fetoprotein and liver enzymes, together with physical assessment and imaging techniques. The availability of more accurate serum markers may facilitate screening and early diagnosis, which will improve prognosis. This retrospective cohort analysis included 50 consecutive patients with cirrhosis and single or multifocal HCC and 40 control subjects with no liver disease or risk factors for viral hepatitis. Expression of epidermal growth factor-like domain 7 (EGFL7), osteopontin (OPN), and prostaglandin E2 (PGE2) were detected using an enzyme-linked immunosorbent assay. The mean serum levels of EGFL7, OPN, and PGE2 in the HCC group were 132.11 pg/mL, 11.77 ng/mL, and 179.37 pg/mL, respectively, which were all significantly higher than the levels in the control group (23.03 pg/mL, 2.31 ng/mL, and 47.36 pg/mL, respectively; P < 0.001). Serum levels of EGFL7, OPN, and PGE2 levels may thus be useful for screening and surveillance of HCC among high-risk populations, and have the potential to improve prognosis of these patients.

Surgical safety distances in the infratemporal fossa: three-dimensional measurement study

The wedge-shaped infratemporal fossa is a constricted space and has long been a surgical challenge, mainly due to difficulties in access. Three-dimensional (3D) reconstruction of the skull, internal carotid artery (ICA), and internal jugular vein (IJV) was carried out using enhanced computed tomography (CT) data, to measure the safety distances in relation to infratemporal fossa surgery. Fifty enhanced CT datasets were selected to reconstruct 3D images by segmentation technique. The anatomical routes of the ICA, IJV, and the styloid process (SP) were observed. The following were measured: SP length, height of the pterygoid plates (PP height), distances from the pterygoid process (antero-inferior and anterosuperior border) to the leading edge of the ICA (PP-ICA (inferior), PP-ICA (superior)), and distance between the most prominent point of the zygomatic arch and the medial pterygoid plate (Zyg-MPP). The mean measurements of SP length, PP height, and the distances PP-ICA (inferior), PP-ICA (superior), and Zyg-MPP were 30.64 mm, 26.61 mm, 31.16 mm, 34.37 mm, and 51.37 mm, respectively. No significant differences were observed by age group, except the distance of PP-ICA (inferior) on the left side. In centres without intraoperative navigation facilities, proper knowledge of the anatomy, particularly of bony landmarks and the safe distances to nearby neurovascular structures, can provide useful information to ensure safe operations.

Role of mechanical strain and estrogen in modulating osteogenic differentiation of mesenchymal stem cells (MSCs) from normal and ovariectomized rats

Bone's adaptability to loading depends upon the process of bone remodeling. This adaptive mechanism is restricted in postmenopausal osteoporosis. Differentiation of mesenchymal stem cells (MSCs) is crucial to bone remodeling and regeneration. It is well accepted that mechanical loading influences the fate of MSC differentiation. The aim of this study was to explore the possible restricted mechanism in osteoporotic condition, through investigating response of MSCs from both sham-operated and ovariectomized rats. MSCs were exposed to estrogen and mechanical strain (2%, 1Hz, 6h/day) for 3 days. Osteogenic differentiation and β-catenin protein in MSCs were examined. Exposure to estrogen and mechanical strain alone enhanced expression of Runx2 (Cbfα1), type I collagen (ColI) and activated β-catenin protein in MSCs from both sham-operated and OVX rats. MSCs from both sham-operated and OVX rats stimulated with both mechanical strain and estrogen had higher expression of osteogenic genes and activated β-catenin protein than these cells exposed to estrogen and mechanical strain alone. Osteoporotic MSCs had lower expression of osteogenic genes and protein in the absence and presence of stimulation than did MSCs from sham-operated rats. Cumulatively, our results indicate that mechanical strain and estrogen in vitro enhance osteogenic potential and activation of β-catenin in MSCs from both sham-operated and OVX rats. Estrogen augments strain-induced osteogenic potential and activity of β-catenin in MSCs.

Histone demethylase retinoblastoma binding protein 2 regulates the expression of α-smooth muscle actin and vimentin in cirrhotic livers

Liver cirrhosis is one of the most common diseases of Chinese patients. Herein, we report the high expression of a newly identified histone 3 lysine 4 demethylase, retinoblastoma binding protein 2 (RBP2), and its role in liver cirrhosis in humans. The siRNA knockdown of RBP2 expression in hepatic stellate cells (HSCs) reduced levels of α-smooth muscle actin (α-SMA) and vimentin and decreased the proliferation of HSCs; and overexpression of RBP2 increased α-SMA and vimentin levels. Treatment with transforming growth factor β (TGF-β) upregulated the expression of RBP2, α-SMA, and vimentin, and the siRNA knockdown of RBP2 expression attenuated TGF-β-mediated upregulation of α-SMA and vimentin expression and HSC proliferation. Furthermore, RBP2 was highly expressed in cirrhotic rat livers. Therefore, RBP2 may participate in the pathogenesis of liver cirrhosis by regulating the expression of α-SMA and vimentin. RBP2 may be a useful marker for the diagnosis and treatment of liver cirrhosis.

Crosstalk of Ras and Rho: activation of RhoA abates Kras-induced liver tumorigenesis in transgenic zebrafish models

RAS and Rho small GTPases are key molecular switches that control cell dynamics, cell growth and tissue development through their distinct signaling pathways. Although much has been learnt about their individual functions in both cell and animal models, the physiological and pathophysiological consequences of their signaling crosstalk in multi-cellular context in vivo remain largely unknown, especially in liver development and liver tumorigenesis. Furthermore, the roles of RhoA in RAS-mediated transformation and their crosstalk in vitro remain highly controversial. When challenged with carcinogens, zebrafish developed liver cancer that resembles the human liver cancer both molecularly and histopathologically. Capitalizing on the growing importance and relevance of zebrafish (Danio rerio) as an alternate cancer model, we have generated liver-specific, Tet-on-inducible transgenic lines expressing oncogenic Kras(G12V), RhoA, constitutively active RhoA(G14V) or dominant-negative RhoA(T19N). Double-transgenic lines expressing Kras(G12V) with one of the three RhoA genes were also generated. Based on quantitative bioimaging and molecular markers for genetic and signaling aberrations, we showed that the induced expression of oncogenic Kras during early development led to liver enlargement and hepatocyte proliferation, associated with elevated Erk phosphorylation, activation of Akt2 and modulation of its two downstream targets, p21Cip and S6 kinase. Such an increase in liver size and Akt2 expression was augmented by dominant-negative RhoA(T19N), but was abrogated by the constitutive-active RhoA(G14V). Consequently, induced expression of the oncogenic Kras in adult transgenic fish led to the development of hepatocellular carcinomas. Survival studies further revealed that the co-expression of dominant-negative RhoA(T19N) with oncogenic Kras increased the mortality rate compared with the other single or double-transgenic lines. This study provides evidence of the previously unappreciated signaling crosstalk between Kras and RhoA in regulating liver overgrowth and liver tumorigenesis. Our results also implicate that activating Rho could be beneficial to suppress the Kras-induced liver malignancies.

Unique roles of Schistosoma japonicum protein Sj16 to induce IFN-γ and IL-10 producing CD4(+)CD25(+) regulatory T cells in vitro and in vivo

Various proteins are expressed during different stages of schistosome development that are essential for cercarial penetration of vertebrate skin and evasion of host immune response. CD4(+)CD25(+) regulatory T cells are important in modulating immune responses towards helminth infections. Schistosoma japonicum protein Sj16 present in the secretions of schistosomula has been shown to have anti-inflammatory effects; however, it is uncertain whether Sj16 can induce CD4(+)CD25(+) regulatory T cells to participate in the regulation of early infection. In this study, we demonstrate a relationship between recombinant Sj16 (rSj16) and the induction of CD4(+)CD25(+) Foxp3(+) regulatory T cells. An increase in CD4(+)CD25(+) T cells was observed both in splenic cells from mice injected with rSj16 and the cells pretreated with rSj16, respectively. The induced CD4(+)CD25(+) T cells suppressed CD4(+)CD25(-) T-cell proliferation; furthermore, IFN-γ and IL-10 released from rSj16-stimulated cells contribute to this suppression. Additionally, rSj16-treated bone marrow dendritic cells (BMDCs) demonstrate an immature phenotype and play a role in the conversion of CD4(+)CD25(-) T cells into suppressive CD4(+)CD25(+) regulatory T cells. Our study identified a new CD4(+)CD25(+) T-cell population that induced by rSj16 and suggests that an IFN-γ-biased microenvironment during early infection of schistosome may favour the establishment of infection.

First-principles calculation of structural, mechanical, magnetic and thermodynamic properties for γ-M23C6 (M = Fe, Cr) compounds

We report the results of our first-principles calculations of structural stability, mechanical, magnetic, and thermodynamic properties for γ-M(23)C(6) (M = Fe, Cr) compounds with each of the four metal Wyckoff sites being occupied in turn by Fe. The thermodynamic properties and the temperature dependence of the mechanical behavior of γ-M(23)C(6) compounds are investigated based on the quasi-harmonic Debye model. The results show that the thermodynamic properties of γ-M(23)C(6) (M = Fe, Cr) compounds are more dependent on the position of Fe atoms than the amount of Fe.

Band structures of phononic-crystal plates in the form of a sandwich-layered structure

This study investigates the propagation of Lamb waves in phononic-crystal plates in the form of a sandwich-layered structure. The composite plates are composed of periodic layers bilaterally deposited on both sides of the homogeneous core layer. Using the analyses of the band structures and the transmission spectra, it is revealed that the core layer may induce significant modulations to the lower-order Lamb modes. The modulations are ascribed to the reshaped particle displacement fields of the eigenmodes. Prominently, the core layer made of soft material (rubber) combines the identical eigenmodes of the periodic layers into a pair of asymmetric and symmetric modes in which case the periodic layers vibrate independently. However, the core layer made of hard material (tungsten) or medium hardness material (silicon) couples the periodic layers tightly, in which case the composites vibrate as a whole. In addition, it is found that the phononic band gaps are very sensitive to the thickness of the core layer; this could be indispensable to practical applications such as bandgap tuning.

[Construction of the HSV-1 strain HF amplicon and study on its unversal function between different HSV serotypes]

The study aimed to construct the amplicon vector of HSV-1 strain HF and explore its universal package function between different serotypes of HSV. OriS and pac elements were obtained by enzyme digestion from the Plasmid BAC-HSV-1 strain HF and sequenced. With red fluorescence (DsRed) as a reporter gene, the amplicon vector of HSV-1 strain HF was constructed based on pSilencer2.0-U6. The amplicon vector was transfected into Vero cells by lipofectamine 2000, then packaged by HSV-1 strain HF and HSV-2 strain HG52 as helper virus separately. The supernatant was collected after cytopathic effect. Red fluorescence was observed in Vero cells reinfected by the supernatant. In this study,the amplicon vector of HSV-1 strain HF was successfully constructed and it could be packaged by HSV-1 strain HF and HSV-2 strainHG52.

Laminar shear stress promotes endothelial cell migration and inhibits cell apoptosis in the presence of hydroxyurea

Cell migration plays important roles in both physiological and pathological processes. Recent studies have shown that hydroxyurea, which is an anti-proliferative inhibitor, can affect cell morphology and specific gene expression of endothelial cells (ECs). In vivo, the functions of ECs are modulated by shear stress. It is well known that shear stress can have effects on EC migration by affecting cell morphology, cytoskeletal arrangement and cell-cell junction, and activating mechanosensors, inducing the changes of signaling pathways, and then increasing or decreasing the expression of gene and protein. However, the influences of hydroxyurea on EC function under shear stress are still unclear. In present study, we investigated the effects of hydroxyurea on EC proliferation, apoptosis and migration under laminar shear stress. The results showed that hydroxyurea prevented growth of ECs in a dose-dependent manner. Hydroxyurea at 2 mM completely inhibited the proliferation of ECs. The results also demonstrated that hydroxyurea induced EC apoptosis, but it was inhibited by 15.27 dyn/cm2 laminar shear stress. Furthermore, shear stress induced cell migration in the presence of hydroxyurea. Therefore, 2 mM hydroxyurea, which completely inhibited the proliferation of HUVECs, could be used to eliminate any confounding effect of shear stress on proliferation in shear stress-induced cell migration. These results also do confirm that shear stress plays important roles in achieving and maintaining the stabilization of ECs.

Assessment of effects of the rising atmospheric nitrogen deposition on nitrogen uptake and long-term water-use efficiency of plants using nitrogen and carbon stable isotopes

This study assesses the effects of the atmospheric nitrogen (N) deposition on the N uptake and the long-term water-use efficiency of two C(3) plants (Agropyron cristatum and Leymus chinensis) and two C(4) plants (Amaranthus retroflexus and Setaria viridis) using N and C stable isotopes. In addition, this study explores the potential correlation between leaf N isotope (δ(15)N) values and leaf C isotope (δ(13)C) values. This experiment shows that the atmospheric N deposition has significant effects on the N uptake, δ(15)N and leaf N content (N(m)) of C(3) plants. As the atmospheric N deposition rises, the proportion and the amount of N absorbed from the simulated atmospheric deposition become higher, and the δ(15)N and N(m) of the two C(3) plants both also increase, suggesting that the rising atmospheric N deposition is beneficial for C(3) plants. However, C(4) plants display different patterns in their N uptake and in their variations of δ(15)N and N(m) from those of C(3) plants. C(4) plants absorb less N from the atmospheric deposition, and the leaf N(m) does not change with the elevated atmospheric N deposition. Photosynthetic pathways may account for the differences between C(3) and C(4) plants. This study also shows that atmospheric N deposition does not play a role in determining the δ(13)C and in the long-term water-use efficiency of C(3) and C(4) plants, suggesting that the long-term water-use pattern of the plants does not change with the atmospheric N input. In addition, this study does not observe any relationship between leaf δ(15)N and leaf δ(13)C in both C(3) and C(4) plants.

[Construction of a recombinant BAC-HSV-1 strain HF with a GFP reporter gene and characterization of its infectious progeny virus]

To construct the plasmid of BAC-HSV-1 with GFP reporter gene and research the biological property of its infectious progeny virus. We constructed the plasmid C223-UL43-left-arms-UL47-right-arms which carried the homologous sequences of HSV-1. Liposome embedding method was used to transfect HSV-1 genome and the plasmid C223-UL43-left-arms-UL47-right-arms linearized by Mlu I digestion into Vero cells. After the successful homologous recombination in the eukaryotic cells, the recombinant BAC-HSV-1 with GFP reporter gene was generated. Then, the positive CPE were taken by plaque purification and by hirt extraction during the moment of the circularization of HSV-1 DNA, and the plasmid of BAC -HSV-1 was acquired. Electroporation was used to transfect the BAC -HSV-1 into DH10B, and then the single colonies of interest were confirmed both by MluI digestion and PCR. Experimental group and the control group cells were given BAC-HSV-1 plasmid and HSV-1 genomic DNA respectively to produce the BAC-HSV-1 and HSV-1 progeny virions. Vero cells were inoculated with the progeny virions at MOI = 0.1 and then a TCID50 assay was performed to determine the titers of virons in the two groups at 48 hours post inoculation. The plasmid BAC-HSV-1 was successfully constructed by the restriction enzyme analysis and the PCR. The titers of progeny virions were calculated by the TCID50 assay. No significant difference in the titers of virions between two groups was observed (P > 0.05). The infectious BAC-HSV-1 shuttle virus/plasmid between eukaryotic and prokaryotic cells was successfully constructed.

The small GTPase Cdc42 promotes membrane protrusion during polar body emission via ARP2-nucleated actin polymerization

Polar body emission is a specialized cell division throughout the animal kingdom, serving to reduce chromosome ploidy while preserving the egg cytoplasm. Critical to polar body emission are the asymmetric positioning of the meiotic spindle prior to anaphase, with one pole attached to the oocyte cortex, and the simultaneous membrane protrusion during subsequent cytokinesis. We have shown that, during Xenopus oocyte maturation, the small GTPase Cdc42 promotes membrane protrusion while a classical RhoA contractile ring forms and constricts at the base of the protrusion. We report here that treating oocytes with low concentrations of nocodazole diminished the size of metaphase I spindles and prevented polar body emission, and yet an active Cdc42 cap of correspondingly diminished size still developed, on time, atop of the spindle pole. Conversely, treating oocytes with low concentrations of taxol resulted in a spindle with multiple poles attached to the cortex, but still each of these poles were associated with activated cortical Cdc42 at the appropriate time. Therefore, the asymmetric positioning of the meiotic spindle with one pole anchored to the cortex is a prerequisite for Cdc42 activation. Furthermore, we demonstrated that the Cdc42-regulated F-actin nucleator ARP2/3 complex was similarly localized at the cortex of the protruding polar body membrane, suggesting that Cdc42 promotes membrane protrusion through an F-actin meshwork mechanism. Finally, we demonstrated that Cdc42 and RhoA formed similarly complementary activity zones during egg activation and that inhibition of Cdc42 prevented second polar body emission. Therefore, Cdc42 activation likely promotes membrane protrusion during polar body emission in widespread systems.

Predicting microstructures in polymer blends under two-step quench in two-dimensional space

The formation of nanostructures during two-step quench in binary polymer systems having various types of liquid miscibility gaps are investigated systematically via computer simulations using the phase field method. Coupled liquid spinodal decomposition and fluid flow processes are considered by solving simultaneously the Cahn-Hilliard and Navier-Stokes equations. Various interesting phenomena and morphological patterns are predicted. It is found that the primary microstructures developed at the first quench and isothermal holding temperature greatly affect the secondary microstructures developed during the second quench and isothermal holding. Depending on the morphology and scale of the primary microstructure, either multicore and multishell or unicore and unishell structures are predicted. The breakup of annuluses in a core-shell structure in two dimensions is analyzed. The effects of viscosity on the formation of core-shell structure and on the growth and coarsening behaviors of bimodal droplets produced by the two-step quench in systems are also investigated.

Temperature effects on the band gaps of Lamb waves in a one-dimensional phononic-crystal plate (L)

This study investigates the temperature-tuned band gaps of Lamb waves in a one-dimensional phononic-crystal plate, which is formed by alternating strips of ferroelectric ceramic Ba(0.7)Sr(0.3)TiO(3) and epoxy. The sensitive and continuous temperature-tunability of Lamb wave band gaps is demonstrated using the analyses of the band structures and the transmission spectra. The width and position of Lamb wave band gaps shift prominently with variation of temperature in the range of 26 °C-50 °C. For example, the width of the second band gap increases from 0.066 to 0.111 MHz as the temperature is increased from 26 °C to 50 °C. The strong shift promises that the structure could be suitable for temperature-tuned multi-frequency Lamb wave filters.

Metallic liquids and glasses: atomic order and global packing

In this Letter, we have revealed the common structural behavior of metallic glasses through scrutinizing the evolution of pair distribution functions from metallic liquids to glasses and statistically analyzing pair distribution functions of 64 metallic glasses. It is found that the complex atomic configuration in metallic glasses can be interpreted globally as a combination of the spherical-periodic order and local translational symmetry. The implications of our study suggest that the glass transition could be visualized mainly as a process involving in local translational symmetry increased from the liquid to glassy states.