Leocarpinolide B Attenuates Collagen Type II-Induced Arthritis by Inhibiting DNA Binding Activity of NF-κB.

Rheumatoid arthritis (RA) is a chronic autoimmune disease triggered by a cascading inflammatory response. Sigesbeckia Herba (SH) has long been utilized as a traditional remedy to alleviate symptoms associated with rheumatism. Our previous study found that leocarpinolide B (LB), a sesquiterpene lactone isolated from the whole plant of SH, possesses potent a anti-inflammatory effect on macrophages. This study was designed to evaluate the therapeutic effects of LB on RA, and further investigate the underlying mechanisms. In collagen type II-induced arthritic mice, LB was demonstrated to decrease the production of autoimmune antibodies in serum and inflammatory cytokines in the joint muscles and recover the decreased regulatory T lymphocytes in spleen. Moreover, LB significantly suppressed the inflammatory infiltration, formation of pannus and bone erosion in the paw joints. In vitro testing showed that LB inhibited the proliferation, migration, invasion, and secretion of inflammatory cytokines in IL-1ß-induced human synovial SW982 cells. Network pharmacology and molecular docking suggested NF-κB p65 could be the potential target of LB on RA treatment, subsequent experimental investigation confirmed that LB directly interacted with NF-κB p65 and reduced the DNA binding activity of NF-κB in synovial cells. In conclusion, LB significantly attenuated the collagen type II-induced arthritis, which was at least involved in the inhibition of DNA binding activity of NF-κB through a direct binding to NF-κB p65. These findings suggest that LB could be a valuable lead compound for developing anti-RA drugs.

Tissue inhibitor of metalloproteinase-2 (TIMP-2) from red seabream (Pagrus major): Molecular cloning and biochemical characterization of highly expressed recombinant protein.

The tissue inhibitor of metalloproteinase-2 (TIMP-2) is originally characterized as an endogenous inhibitor of matrix metalloproteinases (MMPs) to response collagenolysis associated with immune challenge. In this study, the cDNA encoding TIMP-2a gene from red seabream (Pagrus major) muscle was cloned. It was 585 bp encoding a putative protein of 194 amino acids, which comprised all recognized functional domains and showed the high identity to TIMP-2as from other teleost fishes, revealing it belongs to TIMP-2a family. Soluble rTIMP-2a was efficiently expressed using a new constructed pPIC9K-rTIMP-2a vector with high inhibitory activity against to MMP-2 and MMP-9. The recombinant TIMP-2a tagged with 6 histidine residues showed the molecular mass of 23 kDa and isoelectric point of 6.50. Furthermore, the 6 disulfide bonds formed by 12 conserved cysteine residues were identified as functional motifs for its structural stability. In addition, rTIMP-2a possessed the high inhibitory activity against gelatinolytic hydrolysis and degradation of type I collagen which induced by endogenous MMPs in muscle. The results revealed the properties and inhibitory function of rTIMP-2a, which may be a pivotal role in regulation gelatinolytic MMPs metabolization during defense mechanism.

Quantitative determination of amphetamine-type stimulants in sewage and urine by hybrid monolithic column solid-phase microextraction coupled with UPLC-QTRAP MS/MS.

A needle-solid-phase microextraction (SPME) method based on hybrid monolithic column (HMC) was proposed for simultaneous separation and extraction of seven amphetamine-type stimulants (ATSs) (amphetamine, methamphetamine, cathinone, methcathinone, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, and 3,4-methylenedioxyethylamphetamine), combining with ultra-performance liquid chromatography-triple quadrupole/linear ion trap mass spectrometer (UPLC-QTRAP MS/MS). Thiol functionalized HMC (T-HMC) showed high extraction efficiency and excellent elution results towards target analytes, among three kinds of single/bi-functionalized HMCs. Various parameters of SPME operation and analytical performance were investigated systematically. The adsorption mechanism of T-HMC to ATSs was also discussed and explained as a mixed mode of electrostatic and hydrophobic interactions. Under the optimum experimental conditions, the proposed T-HMC needle-SPME-UPLC-QTRAP MS/MS method was rapid and convenient with good accuracy, low sample consumption, high sensitivity and strong anti-interference ability. This method was successfully applied to quantitative determination of seven trace ATSs in complex sewage and urine samples. In view of abundant types of HMCs, the needle-SPME based on functional HMC also had the potential to selectively separating and enriching other tract new psychoactive substances in complex matrices, and could provide a reliable tool for drug monitoring, especially in applications for forensic analysis and drug abuse.

Paramyosin from field snail (Bellamya quadrata): Structural characteristics and its contribution to enhanced the gel properties of myofibrillar protein.

To assess the blending effect of field snails with grass carp muscle, the effects of paramyosin (PM) and actomyosin (AM) with different mixture ratios on the gel properties of the binary blend system were investigated in our work. The purified PM from field snail muscle was about 95 kDa on SDS-PAGE. Its main secondary structure was α-helix, which reached to 97.97 %. When the amount of PM increased in the binary blend system, their rheological indices and gel strength were improved. The water holding capacity (WHC) increased to 86.30 % at a mixture ratio of 2:8. However, the WHC and the area of immobile water (P22) dramatically decreased, and the area of free water (P23) increased when the mixture ratio exceeded 4:6. The low level of PM in binary blend system promoted the formation of a homogenous and dense gel network through non-covalent interactions as observed results of SEM and FTIR. When there were redundant PM molecules, the development of heterostructure via hydrophobic interaction of tail-tail contributed to the reduced gel properties of the binary blend system. These findings provided new insight into the binary blend system of PM and AM with different ratios to change the gel properties of myofibrillar protein.

[Hemilateral bone longitudinal transport technique for the treatment of hemilateral defects of long bones of lower limbs].

OBJECTIVE: To explore clinical efficacy of Ilizarov hemilateral bone longitudinal transport technique in treating hemilateral bone defects associated with chronic osteomyelitis of lower extremity long bones. METHODS: Clinical data of 13 patients with hemilateral bone defects caused by chronic osteomyelitis of lower extremity long bones and treated by Ilizarov hemilateral bone longitudinal transport technique were retrospective analyzed, including 10 males and 3 female, aged from 14 to 55 years old;4 patients occurred femoral and 9 patients occurred tibial;10 patients were diagnosed as traumatic osteomyelitis and 3 patients as hematogenous osteomyelitis. The anatomical classification of Cierny-Mader in 13 patients was type Ⅲ. Bone and wound healing, postopertaive complication, and bony and functional results were observed by Paley evaluation standard. RESULTS: After removing external fixator, all patients were followed up from 6 to 70 months. Transporting time ranged from 54 to 158 d. And the time in external fixation ranged from 6.8 to 19.5 months. External fixation index (EFI) ranged from 1.23 to 1.6 months/cm. According to Paley's evaluation criteria, bony results were excellent in 13 patients;functional results showed excellent in 12 patients and good in 1 patient. Two patients occurred poor union on the docking sites and healed with autogenous iliac bone graft. The callus at the extended area was poorly mineralized and improved significantly when treated with low-intensity pulsed ultrasound in one patient. All patients had good wound healing without recurrence of osteomyelitis and refracture. There was no vascular and nerve injury and axial deviation in all patients and they were satisfied with the appearance and function of lower limbs. The range of motion of knee and ankle joint before operation was 120 ° to 150 ° and 35 °to 80 ° respectively, and at the latest follow-up was 110 ° to 140 ° and 30 ° to 75 ° . CONCLUSION: Ilizarov hemilateral bone longitudinal transport technique is effective in treating infective hemilateral bone defects of lower extremity long bones, which could not only simplify architecture of external fixation, but also reduce the number of fixation pins, shorten the time in external fixator and decrease the incidence of pin tract infection. However, this technique is highly demanding, and the growth of callus in extended region and healing of bone apposition should be noticed.

Effect of electroporation-mediated transfecting recombinant plasmid pIRES-hBMP2-hVEGF165 on mandibular distraction osteogenesis.

Distraction osteogenesis requires a long consolidation period and has a low but real failure rate. Bone morphogenetic proteins (BMPs) accelerate bone deposition in fractures and critical-sized bone defects. Vascular endothelial growth factor (VEGF) is a promising reagent for inducing angiogenesis, and is an essential coordinator of extracellular matrix remodeling, angiogenesis, and bone formation in the growth plate. However, their effects on mandibular distraction osteogenesis are unknown. We investigated the effect of local delivery of plasmid pIRES-hBMP-2-hVEGF165 into a distraction area by electroporation-mediated approach.A New Zealand rabbit model were used. Activation of the device was commenced after 3 days of latency period and proceeded at the rate of 0.8 mm per day for 7 days. After the completion of activation, the rabbits were randomly divided into 5 groups: group A: recombinant plasmid 2 µg (0.1 µg/µL) pIRES-hVEGF165-hBMP2 was injected into the distraction area after the completion of activation; group B: recombinant plasmid pIRES-hBMP2 was injected into the distraction area; group C: recombinant plasmid pIRES-hVEGF165 was injected into the distraction area; group D: pIRES was injected into the distraction area, and group E: normal saline was injected into the distraction area. After injection every group used electroporation. Subsequently, the rabbits were examined by quantitative computed tomography, mechanical testing, and histomorphometric analysis.BMD of newly formed bone of the distraction area in groups A, B, and C were remarkably higher than those of groups D and E at different times (P < 0.001). At 4 and 8 weeks of consolidation, the crushing strength of 3 points of the newly formed bone in group A was remarkably higher than those of groups B, C, D, and E (P < 0.01). The results demonstrated statistically remarkable increase in regenerated bone in the gene-transfected groups.Electroporation-mediated transfecting recombinant plasmid pIRES-hVEGF165-hBMP2 could produce a satisfactory proceeding of osteogenesis and calcification, which surpassed that of the control group. This finding indicates that a combination of VEGF and BMP may make osteogenesis and angiogenesis appear at the same time. Furthermore, it may magnify the effect of single growth factor, and promote growth and reparative process of bone.

Treatment of Femoral Head Osteonecrosis with Ozone Therapy: Pilot Trial of a New Therapeutic Approach.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) is a progressive and painful disorder due to impaired blood supply to the femoral head, yet little is known about the effect of ozone therapy in femoral head necrosis. OBJECTIVES: We aimed to evaluate the clinical and radiographic outcomes of ozone therapy in the treatment of ONFH. STUDY DESIGN: Nonrandomized clinical trial. SETTINGS: The study was conducted in a single-center, academic institution. METHODS: A total of 71 patients (107 hip joints) with Association Research Circulation Osseous (ARCO) stage-I, II, III, and IV ONFH were included and assigned to undergo either intraarticular O2-O3 mixture hip injections with ozonated autohemotherapy (ozone therapy group, n = 39, 58 hip joints) or protected weight bearing (control group, n = 32, 49 hip joints). The primary outcomes included the Visual Analog Scale (VAS) for pain intensity and Harris Hip Score (HHS) for hip function. The secondary outcomes included bone marrow edema examination, and conversion to total hip arthroplasty (THA). RESULTS: Ozone therapy effectively improves VAS for pain intensity and HHS during the follow-up period compared to the control group. Ozone therapy showed a significant resolution of bone marrow edema of the femoral head compared to the control group (P < 0.001). Thirteen of the 49 hips (26.53%) in the control group underwent THA, whereas only 6 hips (10.34%) in the ozone therapy group required THA during a 30-month follow-up (P = 0.041). The cumulative analysis revealed a low rate of conversion to THA in the ozone therapy group (logrank test; P = 0.022). LIMITATIONS: The study is limited by a single treatment protocol in addition to the lack of a randomized design. CONCLUSIONS: Ozone therapy was associated with significant pain relief, improvement in hip function, and bone marrow edema resolution that may delay the need for THA in patients affected by ONFH.Institutional Review Board (IRB) approval number: HK2018-10-28.Clinical trials registration number: ChiCTR1900023449.

A core-shell strategy for constructing a single-molecule junction.

Understanding the effects of intermolecular interactions on the charge-transport properties of metal/molecule/metal junctions is an important step towards using individual molecules as building blocks for electronic devices. This work reports a systematic electron-transport investigation on a series of "core-shell"-structured oligo(phenylene ethynylene) (Gn-OPE) molecular wires. By using dendrimers of different generations as insulating "shells", the intermolecular π-π interactions between the OPE "cores" can be precisely controlled in single-component monolayers. Three techniques are used to evaluate the electron-transport properties of the Au/Gn-OPE/Au molecular junctions, including crossed-wire junction, scanning tunneling spectroscopy (STS), and scanning tunneling microscope (STM) break-junction techniques. The STM break-junction measurement reveals that the electron-transport pathways are strongly affected by the size of the side groups. When the side groups are small, electron transport could occur through three pathways, including through single-molecule junctions, double-molecule junctions, and molecular bridges between adjacent molecules formed by aromatic π-π coupling. The dendrimer shells effectively prohibit the π-π coupling effect, but at the same time, very large dendrimer side groups may hinder the formation of Au-S bonds. A first-generation dendrimer acts as an optimal shell that only allows electron transport through the single-molecule junction pathway, and forbids the other undesired pathways. It is demonstrated that the dendrimer-based core-shell strategy allows the single-molecule conductance to be probed in a homogenous monolayer without the influence of intermolecular π-π interactions.

Effects of partial substitution of NaCl on myofibrillar protein properties from pearl mussel Hyriopsis cumingii muscle: Structural characteristics and aggregation behaviors.

The effects of NaCl and its partial substitutes (KCl, MgCl2 and CaCl2) on solubility, structural characteristics and aggregation behaviors of myofibrillar protein (MP) from pearl mussel muscle were investigated and compared. MP at 0.6 M NaCl was beneficial to protein unfolding and showed excellent potential functional properties. When NaCl was substituted in low level, MPs also showed good solubility and ordered microstructure as well as NaCl, especially MgCl2 and CaCl2, due to the unfolding of α-helical structures and subsequently exposed tyrosine residues and hydrophobic groups. However, the obviously increased disulfide bonds and hydrophobic interactions in high substitution level indicated the excessive non-sodium salts had negative effects on molecular rearrangement, leading to irregular and overly tight of microstructure. Thus, NaCl partially substituted by KCl, MgCl2 and CaCl2 in low substitution level is promising to improve functional properties of MP in low-sodium meat products.

[Determination of thirty trace elements in human plasma by microwave digestion-ICP-MS].

A method for determining 30 trace elements in human plasma was developed by using microwave digestion-ICP-MS. Under the optimized conditions the samples were analyzed by ICP-MS after microwave digestion. The double internal standard elements Rh and Re were used to compensate for matrix suppression effect and sensitivity drift. The analytical results showed that the detection limits of the 30 trace elements were in the range of 0.01-0.68 ng x mL(-1). The recovery rates of the studied elements were from 85% to 119%. The relative standard deviations (RSD) of the method were in the range of 1.7%-10.2%. The national standard reference material GBW 09131 was analyzed by the described method and the measured element values accorded with the standard values. It is indicated that the method is rapid, simple and accurate for determining trace elements in human plasma.

[Determination of thirty three elements in lung cancer tissues of patients with lung cancer by microwave digestion-ICP-MS].

A method for determining 33 elements in lung tissues of patients with lung cancer was developed by using vacuum freeze-drying microwave digestion-ICP-MS. The lung tissue samples were treated by vacuum freeze-drying equipment. After microwave digestion in HNO3-H2O2 solution system, the samples were diluted with the method of constant volume. Under the optimized conditions the samples were analyzed by ICP-MS. The double internal standard elements Rh and Re were used to compensate for matrix suppression effect and sensitivity drift. The analytical results showed that the detection limits of the 33 elements were 0.01-0.45 ng x mL(-1). The national standard reference material GBW(E)080193 bovine liver was analyzed by the described method and the measured element values accorded with the standard values or the reference values. The relative standard deviation (RSD) of the method was 2.1%-14.3%. The recovery rates of the studied elements were 90.1%-117.5%. The contents of 33 elements in lung cancer tissues, paracancerous lung tissues and benign lung tissues of 6 patients with lung cancer were determined by the method. It was indicated that the method is rapid, simple and accurate for determining multi-elements in human lung tissue and other biological samples.

1,8-Cineole Ameliorates LPS-Induced Vascular Endothelium Dysfunction in Mice via PPAR-γ Dependent Regulation of NF-κB.

1,8-Cineole (eucalyptol), a monoterpene, has been widely reported for the anti-inflammatory effects. Our previous data confirmed that 1,8-cineole ameliorated the inflammatory phenotype of human umbilical vein endothelial cells (HUVECs) by mediating NF-κB expression in vitro. At present, we investigated the protection effects of 1,8-cineole on vascular endothelium in lipopolysaccharide (LPS)-induced acute inflammatory injury mice and the potential mechanisms involved in the protection in HUVECs. Results from enzyme linked immunosorbent assays revealed that 1,8-cineole suppressed the secretion of interleukin (IL)-6 and IL-8 and increased the expression of IL-10 in the serum of LPS-induced mice. 1,8-Cineole reduced the inflammatory infiltration and the expression of vascular cell adhesion molecular 1 (VCAM-1) in the sections of thoracic aorta in LPS-induced acute inflammatory mice. Western blotting indicated that 1,8-cineole significantly decreased the phosphorylation of NF-κB p65 and increased the expression of PPAR-γ in the thoracic aorta tissue. 1,8-Cineole increased the expression of PPAR-γ in LPS-induced HUVECs. 1,8-Cineole and rosiglitazone reduced the protein and mRNA levels of VCAM-1, E-selectin, IL-6, and IL-8 in LPS-induced HUVECs, which could be reversed by the action of GW9662 (inhibitor of PPAR-γ). 1,8-Cineole and rosiglitazone blocked the LPS-induced IκBα degradation and NF-κB p65 nucleus translocation, which could be reversed by the pretreatment of GW9662 or silence of PPAR-γ gene. In conclusion, 1,8-cineole attenuated LPS-induced vascular endothelial cells injury via PPAR-γ dependent modulation of NF-κB.

[Preliminary study on identification of heroin from different route with clustering analysis by fourier transform infrared spectroscopy].

In the present paper, using Fourier transform infrared (FTIR) absorption spectrometry, the characteristic peaks of fingerprint infrared spectra of heroin samples from different routes were identified with clustering analysis successfully. It is a very fast, simple and reliable method. That is to say, a new method for the discrimination of heroin seizured from different routes is provided.

[Simultaneous occlusal orthodontics during mandibular distraction osteogenesis].

OBJECTIVE: To study the significance and principle of simultaneous orthodontics during mandibular distraction osteogenesis. METHODS: Totally 11 patients simultaneously underwent occlusal orthodontic treatment for 3-4 months during mandibular distraction osteogenesis. Square-wire and elastic loops were adapted to perform the orthodontics by ways of more frequent adjustment of orthodontic device than routine method. RESULTS: All 11 patients with mandibular micronathia obtained the improved occlusion with their mandibular expected elongation, for instance, their open-bite and teeth displacement were partially corrected. CONCLUSION: Simultanous orthodontics with mandibular distraction osteogenesis may improve the malocclusion, decrease the orthodontic time, and lead the mandibular distraction direction.

Surgical treatment for rabbits' femoral arteries subjected to gunshot wounds combining with seawater immersion.

OBJECTIVE: To investigate the surgical treatment methods and evaluate the outcome of gunshot wounds combining with seawater immersion in rabbits' femoral arteries. METHODS: One hundred healthy New Zealand white rabbits (either sex, 3.14 kg+/-0.61 kg in weight) were randomly divided into a seawater immersion group (n=50) and a simple injury group (n=50). The unilateral femoral arteries of all the rabbits were injured by 0.38 g steel spheres with velocity of 600-800 m/s fired by a 7.62 mm rifle. The rabbits in the seawater immersion group were immersed in seawater (saline content of 2.54%, pH 8.2-8.4, and at 21 degrees C) for 60 minutes but those in the simple injury group were not. After the injured segment (observed by naked eyes) of the femoral artery was excised, the blood flow restoration was reconstructed by direct end-to-end anastomosis, reversed autogenous venous grafting or cryopreserved arterial allografting, according to the length of the arterial defects. At 24 hours, and 7, 14 and 21 days after operation, the blood flow was examined. Operative exploration was performed for the animals with partly or fully obstructed blood flow. The tissues around the anastomosis sites and the grafts were harvested for pathological observation under a light microscope and an electron microscope. RESULTS: In the rabbits with completely transected injury, the unobstructed rates in the first 3 weeks after operation were 80.00% in the seawater immersion group and 86.67% in the single injury group, and no significant difference was found between the two groups (P>0.1). In the rabbits with arterial contusion injury, the unobstructed rates in the first 3 weeks after operation were 86.67% in the seawater immersion group and 82.35% in the single injury group, and no significant difference was found between the two groups (P>0.1). Most thrombosis occurred in the first operative week. Atypical endothelial cells were detected at the anastomosis sites at the first operative week, and the anastomosis sites were lined with endothelial cells in 3 weeks postoperatively. CONCLUSIONS: During the surgical treatment for gunshot wounds combining with seawater immersion, resection of the grossly-injured artery and routine artery reconstruction can obtain satisfactory outcome. Homologous artery is a kind of vascular graft with certain applied value.

Pathological study of rabbits' femoral arteries subjected to gunshot wounds combining with seawater immersion.

OBJECTIVE: To investigate pathological characteristics of gunshot wounds concomitant seawater immersion in rabbits' femoral arteries. METHODS: Thirty rabbits were divided randomly into 3 groups: simple gunshot-wound group (Group I, n = 10), gunshot wound with seawater immersion for 30 mins (Group II, n = 10), and 60 mins group (Group III, n = 10). Femoral arteries were impacted by 0.38 g steel spheres fired with a 7.62 mm rifle. After being wounded, rabbits in Groups II and III were immersed in seawater for 30 or 60 mins, but those in Group I were not. At 2, 4, 6, 8, 12 hours following injury, a 40 mm segment of the artery on each side of the gunshot point were excised and observed by light and electron microscopy. RESULTS: The patterns of arterial injuries were mainly contusion and transection. Completely transected artery was classified as primary-wound-tract area, contused area and shocked area. Compared with those in Group I, the primary-wound-tract and contused areas in Group II manifested obvious swelling in the arterial wall especially at the outside 2/3 of the media. Vacuolar structures were often seen in smooth muscle cells of the media. Intercellular space among the smooth muscle cells were filled with homogeneous acidophilic substances. Deep rugae among endothelial cells flattened or rugal folds lost their longitudinal orientation, and marked fibrin and platelet deposition were noticed. No significant difference was detected between Group II and III. The pathological changes in the shocked area were similar in 3 groups. CONCLUSIONS: For gunshot wounds concomitant seawater immersion in rabbits' femoral arteries, there was a marked swelling of cells and intercellular space in primary-wound-tract area and contusion area. The influence of these pathological changes on surgical reparation deservers further study.

Application of ethidium bromide monoazide for quantification of viable and dead cells of Salmonella enterica by real-time loop-mediated isothermal amplification.

A rapid and efficient method for quantification and discrimination of Salmonella enterica ser. Enteritidis between viable and dead cells killed by heat was developed using ethidium bromide monoazide (EMA) in combination with a real-time loop amplified (Rti-LAMP) DNA assay. The use of 8.0 µg/ml or less of EMA did not inhibit DNA amplification in Rti-LAMP assays derived from viable cells. However, 8.0 µg/ml of EMA notably inhibited DNA amplification and significantly increased the Tp values with dead cells. When the DNA from 2000 viable CFU was subjected to EMA-Rti-LAMP the resulting Tp value was 13 min. In contrast, the DNA from 2000 CFU completely heat destroyed CFU still yielded a Tp value, which was greatly increased to 33.1 min. When the DNA from viable plus heat killed CFU at a ratio of 7:1993 was subjected to EMA-Rti-LAMP, the resulting Tp value was 19.3 min, which was statistically identical (P<0.05) to the Tp value of 19.9 min. obtained with the DNA from only 7 viable CFU. These results indicate that even though 2000 dead cells yielded a Tp value of 33.1 min., low numbers of viable cells in the presence of much higher numbers of dead cells still yielded a linear plot for enumerating viable CFU from Tp values. In addition, propidium monoazide (PMA) was found to be ineffective in distinguishing between low numbers of viable and heat killed cells of S. enterica.

[Surgical treatment of orbital and periorbital fibrous dysplasia].

OBJECTIVE: To explore the surgical approaches to obtain good aesthetic and functional results in the management of orbital and periorbital fibrous dysplasia and related deformities. METHODS: Ten cases of orbital and periorbital fibrous dysplasia were treated surgically. The location, extension and shape of the lesions were identified based on X-ray examination and two and three dimensions CT examinations preoperatively. According to the type of the lesion, different approaches were used to excise the lesion and to reconstruct the orbit. The lesions were radically or partially excised through bicoronal, intraoral and subciliary approach; the orbit was reconstructed with autogenous outer or inner table of calvarium, outer table of mandible, Medpor and prefabricated individual titanic implants. RESULTS: In 10 cases treated surgically, radical excision was employed in 4 cases and partial excision in 6 cases. Autogenous inner table of calvarium was used in 2 cases, Medpor in 2 cases, outer table of mandible in 1 case, and titanic meshwork and prefabricated individual titanic implants in 4 cases to reconstruct the orbit. After the treatment, all patients obtained satisfactory aesthetic and functional results. CONCLUSIONS: Carefully planed surgical approaches with methods for preventing the complications can be used for the treatment of orbital and periorbital fibrous dysplasia and obtaining satisfactory aesthetic and functional results.

[Soil heavy metal cadmium standard limit and range of background value research].

With the rapid development of industrial and agricultural production in China, problems such as excessive soil pollutants worsen year by year, and soil cadmium pollution resulting from the emergence of "cadmium rice" and other food security incidents occur frequently. It causes the extensive concern of society on soil cadmium environmental standards. A soil environmental standard is the foundation for the evaluation of soil environmental quality. The maximum allowable value of cadmium that affects plant and animal and human health is regarded as the basis value all over the world; however, the certification methods and the goals of standard application are different, thus the standard limit has a great difference. Through the research on domestic and foreign soil cadmium standard limits and the soil cadmium background values in China, the soil cadmium background content range values of the provinces and of some types of soil are given. We report the outstanding problems existing in China's current environmental quality standard of soil cadmium. It is proposed that the soil environmental quality standard should allow the coexistence of gradient of soil cadmium standard limit, effective state and total standard limit, and anthropogenic pollution and background values exceeding the standard should be strictly distinguished.

Conformation-controlled electron transport in single-molecule junctions containing oligo(phenylene ethynylene) derivatives.

Understanding the relationships between the molecular structure and electronic transport characteristics of single-molecule junctions is of fundamental and technological importance for future molecular electronics. Herein, we report a combined experimental and theoretical study on the single-molecule conductance of a series of oligo(phenylene ethynylene) (OPE) molecular wires, which consist of two phenyl-ethynyl-phenyl π units with different dihedral angles. The molecular conductance was studied by scanning tunneling microscopy (STM)-based break-junction techniques under different conditions, including variable temperature and bias potential, which suggested that a coherent tunneling mechanism takes place in the OPE molecular wires with a length of 2.5 nm. The conductance of OPE molecular junctions are strongly affected by the coupling strength between the two π systems, which can be tuned by controlling their intramolecular conformation. A cos(2)θ dependence was revealed between the molecular conductance and dihedral angles between the two conjugated units. Theoretical investigations on the basis of density functional theory and nonequilibrium Green's functions (NEGF) gave consistent results with the experimental observations and provided insights into the conformation-dominated molecular conductance.