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ObjectiveTo understand the relative bioavailability (RBA) of cadmium in different aquatic products. Based on the consideration of the gender differences and the relative bioavailability of cadmium in different foods, the physiologically based toxicokinetic (PBTK) model of cadmium was further optimized and verified. The correlation between internal and external exposure in quantitative risk assessment of food safety was optimized, and the provisional tolerable daily intake (PTDI) value of cadmium was derived. MethodsThe relative bioavailability of cadmium in different aquatic products was determined in four-week-old Balb/c female mice. The PBTK model of cadmium metabolism was optimized by ABC-MCMC method using combined internal and external exposure data of cadmium in Shanghai residents, and the PTDI was calculated accordingly. ResultsExcept for scallops and squid, the RBA of aquatic samples was less than 1, indicating that the absorption rate of cadmium in aquatic products was lower than that of cadmium chloride. The higher RBA of squid and scallop may be due to the presence of cadmium in the visceral organs, which is conducive to cadmium absorption and its higher concentration of cadmium. Frying at the temperature less than 160 ℃ reduced cadmium absorption but may increase cadmium absorption at the temperature greater than 160 ℃. The optimized model parameters converged well and the model could reasonably estimate urinary cadmium level according to the external exposure of cadmium. The PTDI value was0.466 4 μg·(kg·day)-1 according to the optimized single-chamber model. ConclusionThe relative bioavailability of cadmium in different foods varies greatly, except for squid and scallops, RBA is less than 1, and cooking processing will affect the RBA of food. The construction of the PBTK model did not only consider the effects of gender differences on cadmium metabolism, but also included the relative bioavailability data to optimize and adjust the correlation coefficient of absorption rate. Compared with the model without RBA adjustment, the adjusted model has enhanced the ability to predict urinary cadmium level, which provides a new, more accurate method for the risk assessment of food safety.
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Objective:To investigate the effect of low-dose ketamine on neuroinflammation and microcirculation in mice with traumatic brain injury (TBI).Methods:Sixty adult male C57BL/6 mice, weighing 22-28 g, were randomly divided into sham-operated group, TBI group, Sham+ketamine group, and TBI+ketamine group ( n=15). A controlled cortical impingement (CCI) method was used to establish TBI models in the later 2 groups. Sham+ketamine group and TBI+ketamine group were intraperitoneally injected with 30 mg/kg ketamine once daily for 3 d at 30 min after TBI; sham-operated group and TBI group were intraperitoneally injected same amount of saline at the same time points. Cerebral cortical blood flow in 6 mice from each group was measured by laser speckle contrast imaging (LSCI) before, immediately after, 30 min after, 1 d after and 3 d after modeling, respectively. Three d after modeling, immunohistochemical staining and immunofluorescent double label staining were used to detect the nuclear translocation of microglia markers, ionized calcin-antibody-1 (Iba-1) and nuclear factor (NF)-κB p65 in damaged cortical brain tissues in 6 mice from each group. The remaining 3 mice in each group were sacrificed and tissue plasma was extracted 3 d after modeling; levels of NF-κB p65, phosphorylated (p)-NF-κB p65, p-IκB and inducible nitric oxide synthase (iNOS) in cortical brain tissues were detected by Western blotting. Expressions of tumor necrosis factor-α (TNF-α), interleukin-1-β (IL-1β) and interleukin-6 (IL-6), iNOS, reactive oxygen species (ROS) and reactive nitrogen species (RNS) in cortical brain tissues were detected by ELISA. Results:LSCI indicated that, 3 d after modeling, relative blood flow in local cerebral microcirculation of TBI+ketamine group was significantly increased compared with that of TBI group ( P<0.05). Immunohistochemical staining indicated that compared with the sham-operated group and Sham+ketamine group, the TBI group and TBI+ketamine group had significantly increased number of Iba-1 positive cells in the cerebral cortex ( P<0.05); compared with the TBI group, the TBI+ketamine group had significantly decreased number of Iba-1 positive cells ( P<0.05). ELISA indicated that compared with the sham-operated group and Sham+ketamine group, the TBI group and TBI+ketamine group had significantly increased expressions of TNF-α, IL-1β, IL-6, iNOS, ROS and RNS in damaged cortical brain tissues ( P<0.05); compared with the TBI group, the TBI+ ketamine group had significantly decreased expressions of TNF-α, IL-1β, IL-6, iNOS, ROS and RNS in damaged cortical brain tissues ( P<0.05). Immunofluorescent double label staining indicated obviously inhibited NF-κB p65 nuclear translocation in TBI+ketamine group when it was compared with TBI group. Western blotting indicated that compared with the sham-operated group and Sham+ketamine group, the TBI+ketamine group had significantly increased iNOS, NF-κB p65, p-NF-κB p65 and P-IκB protein expressions in damaged cortical brain tissues ( P<0.05); compared with the TBI group, the TBI+ketamine group had significantly decreased protein expressions of iNOS, NF-κB p65, p-NF-κB p65 and p-IκB in damaged cortical brain tissues ( P<0.05). Conclusion:Low-dose ketamine reduces neuroinflammation and improves cerebral microcirculatory blood flow after open TBI, whose mechanism may be related to inhibition of microglia NF-κB/iNOS pathway.
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Objective To evaluate the effects of sevoflurane on microglial polarization after traumatic brain injury (TBI) in rats.Methods Seventy-two healthy adult male Sprague-Dawley rats,weighing 230-250 g,were divided into 3 groups (n=24 each) using a random number table method:sham operation group (group Sham),group TBI,and TBI plus sevoflurane anesthesia group (group TBI+Sevo).TBI models were established by using Feeney's method in TBI and TBI+Sevo groups,30 min later 2.4%sevoflurane was inhaled for 1 h once a day for 3 consecutive days in TBI+Sevo group,while pure oxygen was inhaled instead in Sham and TBI groups.At 1,3,7 and 14 days after establishing the model,6 rats were selected,the neurological function was evaluated with the modified neurologic severity score (mNSS),and tail venous blood samples were taken for determination of tumor necrosis factor-a (TNF-α),interleukin-1beta (IL-1β) and IL-6 concentrations by enzyme-linked immunosorbent assay.The rats were then sacrificed,the limbic cortical tissues of brain contusion lesion were taken for determination of cell apoptosis (by TUNEL) and expression of microglial marker lba-1,microglial M1 phenotypic marker CD86 and microglial M2 phenotypic marker CD206 (by Western blot).Results Compared with group Sham,the mNSS score,apoptosis rate of cortical cells,expression of Iba-1,CD86 and CD206,and concentrations of serum TNF-α,IL-1β and IL-6 were significantly increased in TBI and TBI+Sevo groups (P<0.05).Compared with TBI group,the mNSS score,apoptosis rate of cortical cells,expression of Iba-1 and CD86 and concentrations of serum TNF-α,IL-1β and IL-6 were significantly decreased,and the expression of CD206 was up-regulated in TBI+Sevo group (P<0.05).Conclusion The mechanism by which sevoflurane anesthesia reduces TBI may be related to promoting microglial polarization and inhibiting systemic inflammatory response in rats.
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Objective@#To evaluate the effects of sevoflurane on microglial polarization after traumatic brain injury (TBI) in rats.@*Methods@#Seventy-two healthy adult male Sprague-Dawley rats, weighing 230-250 g, were divided into 3 groups (n=24 each) using a random number table method: sham operation group (group Sham), group TBI, and TBI plus sevoflurane anesthesia group (group TBI+ Sevo). TBI models were established by using Feeney′s method in TBI and TBI+ Sevo groups, 30 min later 2.4% sevoflurane was inhaled for 1 h once a day for 3 consecutive days in TBI+ Sevo group, while pure oxygen was inhaled instead in Sham and TBI groups.At 1, 3, 7 and 14 days after establishing the model, 6 rats were selected, the neurological function was evaluated with the modified neurologic severity score (mNSS), and tail venous blood samples were taken for determination of tumor necrosis factor-a (TNF-α), interleukin-1beta (IL-1β) and IL-6 concentrations by enzyme-linked immunosorbent assay.The rats were then sacrificed, the limbic cortical tissues of brain contusion lesion were taken for determination of cell apoptosis (by TUNEL) and expression of microglial marker Iba-1, microglial M1 phenotypic marker CD86 and microglial M2 phenotypic marker CD206 (by Western blot).@*Results@#Compared with group Sham, the mNSS score, apoptosis rate of cortical cells, expression of Iba-1, CD86 and CD206, and concentrations of serum TNF-α, IL-1β and IL-6 were significantly increased in TBI and TBI+ Sevo groups (P<0.05). Compared with TBI group, the mNSS score, apoptosis rate of cortical cells, expression of Iba-1 and CD86 and concentrations of serum TNF-α, IL-1β and IL-6 were significantly decreased, and the expression of CD206 was up-regulated in TBI+ Sevo group (P<0.05).@*Conclusion@#The mechanism by which sevoflurane anesthesia reduces TBI may be related to promoting microglial polarization and inhibiting systemic inflammatory response in rats.
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Objective To explore the mechanism that Staphylococcus aureus(S.aureus) α-toxin(Hla) regulate miR-142 expression and inhibit macrophage phagocytosis.Methods BALB/C mice and RAW264.7 cells were infected with wild type S.aureus(WT S.aureus),Hla deletion S.aureus(△HlaS.aureus) or phosphate buffered saline(PBS),and the expression level of miR-142 of skin tissues and cells were detected.miR-142 mimics and inhibitor were then applied in the RAW264.7 culture to examine the effect on phagocytosis.Direct targeting of miR-142 on protein kinase Cα(PKCα) was assessed by luciferase assay and western blotting.Results miR-142 expression in △HlaS.aureus group were significantly down-regulated than WT S.aureus group(P<0.05).MiR-142 mimics inhibited RAW264.7 phagocytosis ability and inhibitor enhanced RAW264.7 phagocytosis ability.PKCα was directly targeted by miR-142.MiR-142 mimics significantly decreased the mRNA expression levels of PKCα in RAW264.7 cells(P<0.05).Conclusion Hla could promote miR-142 expression in macrophages.MiR-142 could inhibit macrophage phagocytosis through down-regulated PKCα.
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Objective To cxplore the variation of the range of motion (ROM) of operative level after different heights of artificial cervical disc replacement,and to provide guidance for clinical work in selecting appropriate height of artificial cervical disc prosthesis.Methods The preoperative cervical anteroposterior and lateral Ⅹ-rays of 9 fresh male cadaveric cervical spine specimens were obtained to measure the intervertebral height of C5-6,and 3 screened specimens with the height of about 5 mm were included in the experiment.The experiment was designed to test self-control,and other four groups of cervical specimens including intact group,appropriate height (5 mm) of C5.6 artificial cervical disc replacement group,1mm increased (6 mm) group and 2 mm increased (7 mm) group were made biomechanical test sequentially.The specimens were fixed to the cervical three-dimensional movement machine,with a 75 N follower load and pure moments of 2 Nm for flexion/extension 、left/right bending and left/right axial rotation,to measure the ROM of operative level under the condition of changes in 0.2 Nm/s.Results There were no significant differences in the ROM of flexion/extension,lateral bending and axial rotation between 5 mm group and intact group;the ROM of flexion/extension、lateral bending and axial rotation in 6 mm group increased compared with 5 mm group,but the difference was not statistically significant;the ROM of flexion/extension in 7 mm group was significantly less than that of intact,5mm and 6 mm group (9.5°± 1.0° vs 12.5°±0.9°、11.3°±0.8°、11.6°±0.9°),but significantly greater in axial rotation than 6 mm group (10.4°±1.4°vs 8.6°±0.3°),and there was no significant difference in lateral bending compared with other 3 groups.Conclusion 2 adjacent heights of cervical disc prostheses are implantedsuitably when testing the mold of disc prosthesis,the choice of cervical disc prosthesis with 1 mm increased can improve the ROM of operative level to some extent;while the height with 2 mm increased can lead to the ROM of flexion/extension at the operative level reduced,but the ROM of rotation shows an increasing trend.
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Objective To design and construct a controlled adenovirus vector in degradating by itself after induction for solving the problem of stimulating host immune and producing replication adenovirus and providing a secure exogenous gene vectors for clinical practice. Methods Based on the traditional adenovirus vector AdEasyTM system, we inserted the Cre gene which belongs to Cre-LoxP system into the downstream of Tet-On inducible expression system. Two LoxP sites were inserted into two sides of the shuttle plasmid′s right arm genome. Then, the full-length human insulin gene was inserted HindIII enzyme site. After the recombinant adenovirus infected the rat bone marrow-derived mesenchymal stem cells , fluorescent protein expression and insulin secretion were detected before or after induction by Dox. Results A new controlled recombinant adenovirus vector carrying human insulin gene was constructed successfully, and was named AdEasyN/INS. After the transfection of this new vector into QBI-293A cells and rat bone marrow mesenchymal stem cells , green fluorescent protein could be observed. After induction by Dox, both of the ratio of fluorescent cells/total cell and the levels of insulin significantly decreased. Conclusion Construction and preliminary validation of a controlledrecombinant adenovirus vector carrying human insulin gene is constructed successfully , it could infect rat bone marrow mesenchymal stem cells, and degradate by itself after Dox induction, realize the controllability of exogenous gene carrier.
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The steroidal enzyme cytochrome P45017alpha catalyzes the conversion of progesterone and pregnenolone into androgens, androstenedione and dehydroepiandrosterone, respectively, the direct precursors of estrogens and testosterone. Dihydrotestosterone is the principal active androgen in the prostate, testosterone is also an active stimulant of the growth of prostatic cancer tissue. Inhibition of this enzyme as a mechanism for inhibiting androgen biosynthesis could be a worthwhile therapeutic strategy for the treatment of PCA. In this paper, four categories of steroidal inhibitors of cytochrome P45017alpha will be reviewed, a diverse range of steroidal inhibitors had been synthesized and shown to be potent inhibitors of P45017alpha.
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A great deal of comparisons on domestic standards for Orthopedic implants with ISO and ASTM standards have been presented, and some conclusions have been drawn: Domestic standards for orthopedic implants coincide with ISO and ASTM standards in the items of materials, geometry and classification. There are much bigger differences in some key performances of implants such as assembly, fatigue, wear and tear and so on. Some constructive ways have been suggested.
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Test de matériaux , Procédures orthopédiques , Normes de référence , Prothèses et implants , Normes de référenceRésumé
The clinical failure factors of Orthopedic implants which happened recent years have been summarized. The main failure factors are quality of orthopedic implants itself, iatrogenic and patient-derived. The ways to preventive measures have been suggested.
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Procédures orthopédiques , Prothèses et implants , Défaillance de prothèseRésumé
Ten known phenolic compounds including [4]-gingerol (1), [6]-gingerol (2), [10]-gingerol (3), (3S,5S)-3,5-dihydroxy-1-(4-hydroxy-3-methoxyphenyl) decane (4), (3R,5S) -3, 5-dihydroxy-1-(4-hydroxy-3-methoxyphenyl) decane (5), [6]-shogaol (6), [10]-shogaol (7), gingerenone A (8), hexahydrocurcumin (9), and (3R,5R)-3,5-dihydroxy-1,7-bis(4-hydroxy-3-methoxyphenyl) heptane (10), and seven amides including piperine (11), isochavicine (12), isopiperine (13), N-trans-p-coumaroyl tyramine (14), N-trans-feruloyl tyramine (15), N-trans-p-coumaroyl octopamine (16), N-trans-feruloyl octopamine (17), were isolated and identified from the roots of Lycianthes marlipoensis. Compounds 1-13 and 17 were isolated from the genus Lycianthes for the first time.
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Amides , Chimie , Chromatographie , Méthodes , Spectroscopie par résonance magnétique , Méthodes , Phénols , Chimie , Extraits de plantes , Chimie , Racines de plante , Chimie , Métabolisme , Solanaceae , Chimie , MétabolismeRésumé
In order to study the constituents and pharmacology of Tripterygium plants (Tripterygium willfordii Hook.f), a variety of chromatography methods were used. Four compounds were isolated from Tripterygium plant and their structures were elucidated by UV, IR, MS, HR-MS, 1H NMR, 13C NMR and 2D-NMR techniques. The isolated compounds were named as triptonide (1), neo-triptetraolide (2), 2alpha-hydroxytriptonide (3), and 15-hydroxytriptonide (4), separately. Compounds 3, 4 belong to new diterpenoids, which can inhibit the growth of K562 cells (leukemia cells) and HL60 cells (acute myeloid leukemia cells).
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Artificial knee joint simulation test is an important form in the research and evaluation of prosthetic material and design. Natural knee joint could not be tested by conventional instruments because of complex motion and load in movement. Simulation test designed for artificial knee is needed. At present, two kinds of simulation, namely simplification method and complete simulation, are widely used. Complete simulation can be used for simultaneous evaluation of material and design of prosthesis, whereas simplification method is only useful in evaluating the material of prosthesis. In international standards, there are already two protocols for artificial knee joint experiment, namely load control and displacement control. This paper also reviews the evaluation criteria and measurement standards for artificial knee joint simulation test, and then envisages the researches in future.
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Humains , Arthroplastie prothétique de genou , Simulation numérique , Conception assistée par ordinateur , Analyse de panne d'appareillage , Méthodes , Prothèse de genou , Conception de prothèse , MéthodesRésumé
The in vitro antitumor activity of bakuchiol was exploited, compared with tamoxifen. The result of biological activities showed that bakuchiol could inhibit human breast cancer and the IC50 values were 2.89 x 10(-5) mol L(-1) and 8.29 x 10(-3) mol L(-1) against the cells line T-47D and MDA-MB-231 respectively. On the other hand, the key intermediate to synthesize bakuchiol was obtained by the method of Ireland-Claisen rearrangement. Comparing with traditional Claisen rearrangement, the reaction conditions are milder and the reaction reagents are safer.
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Objective In order to avoid potential injuries imposed to human body,it could be feasible to use the musculoskeletal models which can be reconstructed from the cadaver color cryosection(CCC)images,computerized tomography(CT)images,magnetic resonance(MR)images or other images to analyze the dynamic properties of muscles in vivo during human movement.Mothod We reconstruct the lower limb musculoskeletal model and define the uniform ioint coordinate system(JCS)on the model and the subject.The coordinate transformation of the muscle attachment points both on the model and the subject is described in detail.Results The length and the moment arm of the biceps femoris(short head)during knee flexion are calculated and analyzed.Conclusion This method plays an important role in improving the kinematics and dynamic simulation and the muscle force estimation.
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Objective To investigate the influence of Wnt-3a signaling on aggregative growth of dermal papilla cells.Methods Recombinant adenovirus pAdEasy-1/Wnt-3a was constructed at first,and used to transfect cultured dermal papilla cells(DPCs).Then,the growth pattem of DPCs was observed by inverse microscopy;laser confocal microscopy and Western blot were utilized to detect the expressions of Wnt-3a,β-catenin and versican in low-passage DPCs,high-passage DPCs and transfected high-passage DPCs.Results The over-expression of Wnt-3a protein could effectively induce the aggregative growth of DPCs.Laser confocal microscopy showed that the fluorescence intensity of β-catenin and versican increased from 34.16±9.62 and 18.81±9.59 in high-passage DPCs to 87.35±17.28 and 92.18±18.39 in transfected high-passage DPCs(t=11.98,17.88,both P<0.0 1),respectively.Also,Western blot proved a significant increase of expression intensity of β-catenin(15.27±2.17 vs 60.09±7.24,t=10.10,P<0.01)and versican(19.32±2.46 vs 58.46±2.78,t=20.63,P<0.01)in transfected high-passage DPCs compared with untransfected high-passage DPCS.ConclusionsWnt-3a signaling plays an important role in modulating aggregative growth of DPCs,which is mainly through the classical pathway with β-catenin as the key protein.As an important downstream gene of Wnt signaling,vesican is an indispensable part for the modulation of aggregative growth of DPCs.
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OBJECTIVE To establish and optimize the detection of highly pathogenic influenza virus H5N1 subtype by RT-Multiplex (RT-M) PCR method. METHODS The viral RNA was reversely transcripted with universal primer,and the cDNA was sequenced and analyzed. According to the cleavage site of H5 and the conservative sequence of N1,designed two pairs of specificity primer,RT-M PCR was developed by these primers. Then verified the sensitivity of method and its specificity by detecting comparing with NDV,IBV and IBDV. RESULTS The results of H5N1 gene sequence showed the high homology with the Anhui H5N1 strain [avian influenza A/Anhui/1/2005 (H5N1)] after comparing in the GenBank. Two fragments of 302 bp and 567 bp were amplified by RT-M PCR. The method could detect 0.500 pg virus RNA at least,and own high specificity. CONCLUSIONS This method can be used for highly pathogenic avian influenza.
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Objective To construct a recombinant plasmid for expressing the HPV18 E2 gene and develop some materials for HPV18 related disease.Methods The E2 gene of HPV18 was amplified by PCR from PBR322-HPV18 and cloned into PIRES2-EGFP.The sequence of cloned HPV18E2 was confirmed by restriction analysis and DNA sequencing,then transfected into HeLa cells.E2 gene was detected by RT-PCR.Results HPV18 E2 gene fragment was amplified by PCR and ligated to PIRES2-EGFP,then transfected into HeLa cells successfully.The expression of green fluorescence cells was observed by fluorescence microscopy.Specific band could be seen in transfected cells by RT-PCR.Conclusion Recombinant plasmid PIRES2-EGFP is effectively expressed after being transfected into HeLa cells in vitro.
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Objective To study the constituents in Melastoma dodecandrum.Methods The constituents were isolated by chromatographic methods,and their structures were elucidated by spectroscopic evidences.Results Five compounds were purified and their structures were identified as: daucosterol(Ⅰ),oleanolic acid(Ⅱ),avicularin(Ⅲ),3,7,4′-trimethoxyquercetin(Ⅳ),and atractylenolidone(Ⅴ).Conclusion Compound Ⅴ is a new chemical constituent named atractylenolidone.Compound Ⅳ is isolated from M.dodecandrum for the first time.
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Objective:To screen the antagonist of C5a anaphylatoxin,and further to study the dinetic characteristics of interaction between C5a and its anti-sense peptides.Methods:The anti-sense peptides were screened that can interact with C5a selectively by means of dinetic analysis,via biosensor technique.Results:There is one piece of anti-sense peptide(R4) being screened from these four synthesized peptides.The dissociation equilibrium constant(K D) between R4 and the immobilized hC5a is 6.62?10 -6 mol/L and the K D between R4 and L2 is 7.02?10 -7 . Conclusion:Based on the results obtained,it was concluded that the optic biosensor is a ideal and powerful tool to facilitate the kinetic analysis of interaction between sense peptide and its anti-sense peptide and to screen antagonist of biologic activity molecule.