A greenhouse experiment was conducted to elucidate the growth changes and tissues anatomical characteristics of giant reed(Arundo donax L.),a perennial rhizomatous grass,which was cultivated for 70 d in soils contamin...A greenhouse experiment was conducted to elucidate the growth changes and tissues anatomical characteristics of giant reed(Arundo donax L.),a perennial rhizomatous grass,which was cultivated for 70 d in soils contaminated with As,Cd and Pb.The results show that giant reed rapidly grows with big biomass of shoots in contaminated soil,possessing strong metal-tolerance with limited metal translocation from roots to shoots.When As,Cd and Pb concentrations in the soil are less than 254,76.1 and 1 552 mg/kg,respectively,plant height and dried biomass are slightly reduced,the accumulation of As,Cd and Pb in shoots of giant reed is low while metal concentration in roots is high,and the anatomical characteristics of stem tissues are thick and homogeneous according to SEM images.However,plant height and dried biomass are significantly reduced and metal concentration in plant shoots and roots are significantly increased(P<0.05),the stems images become heterogeneous and the secretion in vascular bundles increases significantly when As,Cd and Pb concentrations in the soil exceed 334,101 and 2 052 mg/kg,respectively.The giant reed is a promising,naturally occurring plant with strong metal-tolerance,which can be cultivated in soils contaminated with multiple metals for ecoremediation purposes.展开更多
A simple and sensitive high performance liquid chromatography-chemical vapour generation-atom fluorescent spectrometry （HPLC-CVG-AFS） method was developed and validated for simultaneous determination mercury species...A simple and sensitive high performance liquid chromatography-chemical vapour generation-atom fluorescent spectrometry （HPLC-CVG-AFS） method was developed and validated for simultaneous determination mercury species in Su-He-Xiang-Wan （SHXW） and in tissues of rats, respectively. The species of mercury were separated by a Venusil MP-C 18 （5μm, 150 mm×4.6 ram） column with the optimized mobile phase containing 5% （w/v） acetonitrile, 0.01 mol/L L-cysteine and 0.06 moL/L ammonium acetate. The tissues of rats were freeze-dried after giving the medicine for 10 d, and then added into the solution containing 10% （w/v） HC1, 1% （w/v） sulfocarbamide and 0.15% （w/v） KC1 for increasing extraction rate. The resolutions of Hg2＋, MeHg and EtHg were 1.5 and 2.9, respectively. The detection limits of Hg2＋, MeHg and EtHg were 2.0, 1.0 and 0.9 ng/mL, respectively. The relative standard deviation （RSD） of inter- and intra-day precisions ranged from 1.56% to 2.86%. The recovery rates of three different adding level were 87%-101% （n=6）, and the RSDs were smaller than 8.2%. The results show that no MeHg and EtHg were detected in rat tissues. Only soluble mercury （Hg2＋） was determined for the mercury species of SHXW in rat tissues.展开更多
Based on the self-ordered ring(SOR) fluorescence microscopic imaging technique on a hydrophobic glass slide with Zn 2+ and cetyltrimethyl ammonium bromide(CTMAB) as sensitizer,and poly(vinyl alcohol)-124(PVA-124) and ...Based on the self-ordered ring(SOR) fluorescence microscopic imaging technique on a hydrophobic glass slide with Zn 2+ and cetyltrimethyl ammonium bromide(CTMAB) as sensitizer,and poly(vinyl alcohol)-124(PVA-124) and NH 3-NH 4 Cl(pH 10.00) as the medium,a method has been developed for determining sparfloxacin(SPFX) concentrations in chicken serum and residues in chicken tissues and manures.When the droplet volume was 0.20 μ L,SPFX was determined in the range of 1.38×10-13 ～2.03×10-12 mol.ring-1(or 6.90×10-7 ～1.02×10-5 mol.L-1),and the limit of detection(LOD) was 14fmol.ring-1(or 6.90× 10-8 mol.L-1).The recoveries of SPFX at all different spiked levels are in the range of 90.74%～106.61% when the methanol or acetonitrile were used as extracting agent,respectively,and the relative standard deviations(RSDs) are less than 3.0%.This study expands the applied fields of SOR technique in drug concentrations and residues determination.展开更多
The purpose of this paper is to develop a system for tissue culture and rapid propagation of two ornamental lupins, Minaretie and Russell Prize. In view of screening out the better explant regeneration and suitable cu...The purpose of this paper is to develop a system for tissue culture and rapid propagation of two ornamental lupins, Minaretie and Russell Prize. In view of screening out the better explant regeneration and suitable culture medium, through adding hormone 6-BA, NAA and 2, 4-D into MS and B5 basic culture medium, a series of experiments were carried out with the shoot tips, leaves, leaf petioles and stems from the asepsis seedling. The results showed that the shoot tips had favorableness on the rapidly propagation; MS＋6-BA 0.5 mg. L-1 for first generation, the induction rate of Minaretie and Russell Prize was 90.5% and 95.86% respectivdy; Minaretie had the highest propagation index （6.35） on MS＋6-BA 0.5 mg.L^-1＋NAA 0 mg-L^-1＋GA 30.8 mg. L^1＋AC 2 g. L^-1, but Russell Prize had the highest propagation index （7.24） on MS＋6-BA 0.5 mg.L^-1＋NAA 0.15 mg.L^-1＋GA3 1.0 mg.L^-1＋AC 0.5 g.L^-1; 1/2 MS＋NAA 0.25 mg.L^-1 was the best rooting medium. The ratios of getting roots of Minaretie and Russell Prize were 94.78% and 96.32%, respectively.展开更多
This paper studied on the way of Coleus blumei, the leaf was chosen as explants and was inoculated on 1/2 MS medium with different combinations of 6-benzyladenine （6-BA）, α-naphthaleneacetic acid （NAA） and indole...This paper studied on the way of Coleus blumei, the leaf was chosen as explants and was inoculated on 1/2 MS medium with different combinations of 6-benzyladenine （6-BA）, α-naphthaleneacetic acid （NAA） and indole-3-butyric acid （IBA）. The optimal conditions of callus induction from explants were achieved on the medium containing 6-BA （2.0 mg· L^-1） and NAA （1.0 mg· L^-1）. Shoot tips were induced on the medium containing 6-BA （4.0 mg·L^-1） and NAA （0.5 mg·L^-1）. The same media conditions were found suitable for shoot multiplication, we multiplied shoots rooted best on 1/2 MS medium supplemented with IBA （0.1 mg·L^-1）.展开更多
The study aimed to optimize the induction and differentiation medium by exploreing different tissue culture of Saposhnikovia divaricata （Turcz.） Schischk. In tissue culture with the root, stem segments, young leaf, ...The study aimed to optimize the induction and differentiation medium by exploreing different tissue culture of Saposhnikovia divaricata （Turcz.） Schischk. In tissue culture with the root, stem segments, young leaf, cotyledonary node and axillary bud of Saposhnikovia divaricata （Turcz.） Schischk as explants, a lot of plantleles were obtained and the corresponding plant regeneration-system was established. The results showed that when use MS＋1.0 mg·L^-1 6-BA＋0.2 mg·L^-1 NAA as callus induction medium, the cotyledonary node had the highest bourgeon rate, and its callus was better than any others; MS＋2 mg·L^-1 6-BA＋0.4 mg·L^-1 NAA was the best adventitious buds induction medium, and the best adventitious buds induced condition was 3% sucrose as carbon source, illumination for 12-14 h·d^-1 and pH 5.8, The best rootage medium was 1/2 MS＋0.5 mg·L^-1 NAA.展开更多
OBJECTIVE To investigate the effect of microRNA-32 on cold-induced thermogenesis and brown adipocyte energy metabolism.METHODS To apply the cold-induced thermogenesis model in mice,8-10 week old male C57Bl6 mice were ...OBJECTIVE To investigate the effect of microRNA-32 on cold-induced thermogenesis and brown adipocyte energy metabolism.METHODS To apply the cold-induced thermogenesis model in mice,8-10 week old male C57Bl6 mice were placed within a 6℃fridge for 7d.Control microRNA inhibitor or miR-32 inhibitor(10mg·kg-1)was administered via intraperitoneal injection 16 hbefore the mice were placed in the fridge.Daily core body temperatures were taken using a rectal temperature probe.Mice were euthanized after 7dand brown adipose tissue(BAT),inguinal and epididymal white adipose tissue(WAT),skeletal muscle and liver tissue analysed for changes in morphology and gene expression.RESULTS miR-32 inhibition in vivoinhibits the emergence of beige cells,which function like BAT cells,within WAT.In silico prediction and gene ontology analysis identified Tob1 as a likely target gene of miR-32.miR-32 inhibition led to increased expression of Tob1 whilst mutation of target sequence abolished this effect.Expression of brown adipose markers such as Ucp1,Pgc1α,Pparαand Prdm16 were significantly reduced in inguinal white adipose tissue(P<0.05).There was also a significant decrease in serumfgf21 levels due to the inhibition of Fgf21 expression in BAT(P<0.05).p38/MAPK signalling in brown adipose tissue was also significantly inhibited within brown adipose tissue leading to decreased fgf21 expression and secretion.CONCLUSION Our study shows that miR-32 plays a crucial role in stimulating beige cell emergence by activating p38/MAPK signalling during cold thermogenesis.miR-32 may prove effective as a treatment for obesity by activating cold-induced thermogenesis leading to increased energy metabolism.展开更多
Plant generation of TM-1 via tissue culture was established.The hypocotyledon sections as explants which were cultured in a series of improved MS media containing 0.05～0.10 mg·L-1 IAA,
To study the effects of different concentrations of Abscisic Acid(ABA) on leaf tissue structure of Korla fragrant pear and lay the foundation for the cultivation and regulation of Korla fragrant pear. Using the paraff...To study the effects of different concentrations of Abscisic Acid(ABA) on leaf tissue structure of Korla fragrant pear and lay the foundation for the cultivation and regulation of Korla fragrant pear. Using the paraffin section method, the leaf thickness, the epidermis thickness, the palisade tissue thickness and the sponge tissue thickness were measured; palisade spongy ratio, Cell Tightness(CT) and Cell Looseness(CL) were examined after treatments with exogenous ABA. Leaf thickness, leaf palisade spongy ratio and palisade tissue thickness increased significantly after exogenous ABA treatment compared with CK, while the effect on leaf epidermis was not obvious. The leaf thickness and palisade tissue thickness increased evidently after 70 mg · LABA treatment by 24.89% and 41.10%, respectively. The tissue structures of leaves were more compact, while CL was lower after 70 and 90 mg · LABA treatments. The effects of different concentrations of exogenous ABA could increase the leaf thickness, palisade tissue thickness of Korla fragrant pear and CT, reduced the thickness of spongy tissue and CL. Among those concentrations of exogenous ABA, the effect of spraying 70 mg · Lexogenous ABA was suitable for improving cold resistance of Korla fragrant pear.展开更多
Cell and Tissue Engineering provides exciting opportunities for studying development and Disease.In this talk,we will focus on cell chirality,also known as handedness and left-right(LR)asymmetry,which is an intrinsic ...Cell and Tissue Engineering provides exciting opportunities for studying development and Disease.In this talk,we will focus on cell chirality,also known as handedness and left-right(LR)asymmetry,which is an intrinsic capability of the cell telling left from right(1)The development of the vertebrate body plan with left-right asymmetry requires the emerging chiral morphogenesis at multicellular levels at specific embryonic stages.Changes in orientation of the LR axis due to genetic or environmental factors can lead to malformations and disease.However,the concept of cell chirality has never studied in detail until the recent development of novel engineering tools[2-3].We demonstrate that the cultivation of cells on micropatterned 2D surfaces and in 3D graded hydrogels reveals an intrinsic cellular LR asymmetry,which is dependent of cell phenotype and actin cytoskeleton.With these new tools,we examine the role of cell chirality on the embryonic development of cardiac LR asymmetry [4] as well as the barrier function of endothelium layers [5].We find that Protein Kinase C(PKC)activation reverses the inherent chirality from clockwise to counter clockwise in engineering systems [4-5].Interestingly,activation of PKC signaling reverses the directional bias of chick cardiac C-looping [4].Mediating endothelial cell chirality can regulate the permeability of endothelial layers[5].Overall,our results strongly suggest critical roles of cell chirality in cardiovascular development and disease.展开更多
Brain tissue is one of the softest parts of the human body,composed of white matter and grey matter.The mechanical behavior of the brain tissue plays an essential role in regulating brain morphology and brain function...Brain tissue is one of the softest parts of the human body,composed of white matter and grey matter.The mechanical behavior of the brain tissue plays an essential role in regulating brain morphology and brain function.Besides,traumatic brain injury(TBI)and various brain diseases are also greatly influenced by the brain's mechanical properties.Whether white matter or grey matter,brain tissue contains multiscale structures composed of neurons,glial cells,fibers,blood vessels,etc.,each with different mechanical properties.As such,brain tissue exhibits complex mechanical behavior,usually with strong nonlinearity,heterogeneity,and directional dependence.Building a constitutive law for multiscale brain tissue using traditional function-based approaches can be very challenging.Instead,this paper proposes a data-driven approach to establish the desired mechanical model of brain tissue.We focus on blood vessels with internal pressure embedded in a white or grey matter matrix material to demonstrate our approach.The matrix is described by an isotropic or anisotropic nonlinear elastic model.A representative unit cell(RUC)with blood vessels is built,which is used to generate the stress-strain data under different internal blood pressure and various proportional displacement loading paths.The generated stress-strain data is then used to train a mechanical law using artificial neural networks to predict the macroscopic mechanical response of brain tissue under different internal pressures.Finally,the trained material model is implemented into finite element software to predict the mechanical behavior of a whole brain under intracranial pressure and distributed body forces.Compared with a direct numerical simulation that employs a reference material model,our proposed approach greatly reduces the computational cost and improves modeling efficiency.The predictions made by our trained model demonstrate sufficient accuracy.Specifically,we find that the level of internal blood pressure can greatly influence stress distribution and determine the possible related damage behaviors.展开更多
Current pharmacological therapies used in clinical practice for individuals with cardiac, hepatic, renal or pulmonary fibrosis do not show desirable effects; therefore, new targets of therapy are urgently required. Mi...Current pharmacological therapies used in clinical practice for individuals with cardiac, hepatic, renal or pulmonary fibrosis do not show desirable effects; therefore, new targets of therapy are urgently required. Mitochon- dria play pivotal role in energy production, metabolism, serving as storage tanks of calcium ions and cell fate deter- mination. Recent results of our experiments and other authors＇ studies suggest that the electron transport chain dys- function, electron leakage increasing, the accumulation of fragmented mitochondria, and the impairment in the mi- tophagy system contribute to pathogenesis of tissue fibrosis. Mitochondria targeting compounds exert promise in trea- ring and attenuating the progress of these diseases, indicating potential strategies to target mitochondria in the treat- ment of tissue fibrosis.展开更多
Introductons The biophysical organization of extracellular matrix (ECM) plays an important role in tissue morphogenesis,remodeling and functions. In many types of tissues,e. g. ,blood vessel,nerve,heart,muscle,tendon ...Introductons The biophysical organization of extracellular matrix (ECM) plays an important role in tissue morphogenesis,remodeling and functions. In many types of tissues,e. g. ,blood vessel,nerve,heart,muscle,tendon and ligament,ECM has aniso-展开更多
The ITRM of liver, one of the important indexes of tissue respiratory metabolism in yak, is higher than other tissues. The relationship of ITRM and time belongs to the equation y = aebt. The ITRM of each tissue in rec...The ITRM of liver, one of the important indexes of tissue respiratory metabolism in yak, is higher than other tissues. The relationship of ITRM and time belongs to the equation y = aebt. The ITRM of each tissue in reciprocal yaks were significant(P＜0.05) lower than that of the domestic yaks which showed that the adaptability to hypoxia of the reciprocal yaks were more powerful than the domestic yaks.展开更多
基金Project(20507022) supported by the National Natural Science Foundation of China
文摘A greenhouse experiment was conducted to elucidate the growth changes and tissues anatomical characteristics of giant reed(Arundo donax L.),a perennial rhizomatous grass,which was cultivated for 70 d in soils contaminated with As,Cd and Pb.The results show that giant reed rapidly grows with big biomass of shoots in contaminated soil,possessing strong metal-tolerance with limited metal translocation from roots to shoots.When As,Cd and Pb concentrations in the soil are less than 254,76.1 and 1 552 mg/kg,respectively,plant height and dried biomass are slightly reduced,the accumulation of As,Cd and Pb in shoots of giant reed is low while metal concentration in roots is high,and the anatomical characteristics of stem tissues are thick and homogeneous according to SEM images.However,plant height and dried biomass are significantly reduced and metal concentration in plant shoots and roots are significantly increased(P<0.05),the stems images become heterogeneous and the secretion in vascular bundles increases significantly when As,Cd and Pb concentrations in the soil exceed 334,101 and 2 052 mg/kg,respectively.The giant reed is a promising,naturally occurring plant with strong metal-tolerance,which can be cultivated in soils contaminated with multiple metals for ecoremediation purposes.
基金Projects(20875104, 21075138) supported by the National Natural Science Foundation of China
文摘A simple and sensitive high performance liquid chromatography-chemical vapour generation-atom fluorescent spectrometry （HPLC-CVG-AFS） method was developed and validated for simultaneous determination mercury species in Su-He-Xiang-Wan （SHXW） and in tissues of rats, respectively. The species of mercury were separated by a Venusil MP-C 18 （5μm, 150 mm×4.6 ram） column with the optimized mobile phase containing 5% （w/v） acetonitrile, 0.01 mol/L L-cysteine and 0.06 moL/L ammonium acetate. The tissues of rats were freeze-dried after giving the medicine for 10 d, and then added into the solution containing 10% （w/v） HC1, 1% （w/v） sulfocarbamide and 0.15% （w/v） KC1 for increasing extraction rate. The resolutions of Hg2＋, MeHg and EtHg were 1.5 and 2.9, respectively. The detection limits of Hg2＋, MeHg and EtHg were 2.0, 1.0 and 0.9 ng/mL, respectively. The relative standard deviation （RSD） of inter- and intra-day precisions ranged from 1.56% to 2.86%. The recovery rates of three different adding level were 87%-101% （n=6）, and the RSDs were smaller than 8.2%. The results show that no MeHg and EtHg were detected in rat tissues. Only soluble mercury （Hg2＋） was determined for the mercury species of SHXW in rat tissues.
基金The National Nature Science Foundation of China(Grant Nos.21177163)111 Project B08044+2 种基金the Fundamental Research Funds for the Central Universities(0910KYZY45)"985 Project"of Minzu University of China(MUC 98507-08)"211 Project"of Minzu University of China(MUC 02121103)
文摘Based on the self-ordered ring(SOR) fluorescence microscopic imaging technique on a hydrophobic glass slide with Zn 2+ and cetyltrimethyl ammonium bromide(CTMAB) as sensitizer,and poly(vinyl alcohol)-124(PVA-124) and NH 3-NH 4 Cl(pH 10.00) as the medium,a method has been developed for determining sparfloxacin(SPFX) concentrations in chicken serum and residues in chicken tissues and manures.When the droplet volume was 0.20 μ L,SPFX was determined in the range of 1.38×10-13 ～2.03×10-12 mol.ring-1(or 6.90×10-7 ～1.02×10-5 mol.L-1),and the limit of detection(LOD) was 14fmol.ring-1(or 6.90× 10-8 mol.L-1).The recoveries of SPFX at all different spiked levels are in the range of 90.74%～106.61% when the methanol or acetonitrile were used as extracting agent,respectively,and the relative standard deviations(RSDs) are less than 3.0%.This study expands the applied fields of SOR technique in drug concentrations and residues determination.
文摘The purpose of this paper is to develop a system for tissue culture and rapid propagation of two ornamental lupins, Minaretie and Russell Prize. In view of screening out the better explant regeneration and suitable culture medium, through adding hormone 6-BA, NAA and 2, 4-D into MS and B5 basic culture medium, a series of experiments were carried out with the shoot tips, leaves, leaf petioles and stems from the asepsis seedling. The results showed that the shoot tips had favorableness on the rapidly propagation; MS＋6-BA 0.5 mg. L-1 for first generation, the induction rate of Minaretie and Russell Prize was 90.5% and 95.86% respectivdy; Minaretie had the highest propagation index （6.35） on MS＋6-BA 0.5 mg.L^-1＋NAA 0 mg-L^-1＋GA 30.8 mg. L^1＋AC 2 g. L^-1, but Russell Prize had the highest propagation index （7.24） on MS＋6-BA 0.5 mg.L^-1＋NAA 0.15 mg.L^-1＋GA3 1.0 mg.L^-1＋AC 0.5 g.L^-1; 1/2 MS＋NAA 0.25 mg.L^-1 was the best rooting medium. The ratios of getting roots of Minaretie and Russell Prize were 94.78% and 96.32%, respectively.
文摘This paper studied on the way of Coleus blumei, the leaf was chosen as explants and was inoculated on 1/2 MS medium with different combinations of 6-benzyladenine （6-BA）, α-naphthaleneacetic acid （NAA） and indole-3-butyric acid （IBA）. The optimal conditions of callus induction from explants were achieved on the medium containing 6-BA （2.0 mg· L^-1） and NAA （1.0 mg· L^-1）. Shoot tips were induced on the medium containing 6-BA （4.0 mg·L^-1） and NAA （0.5 mg·L^-1）. The same media conditions were found suitable for shoot multiplication, we multiplied shoots rooted best on 1/2 MS medium supplemented with IBA （0.1 mg·L^-1）.
基金Supported by Natural Science Foundation of Heilongjiang Province (C2005-31)
文摘The study aimed to optimize the induction and differentiation medium by exploreing different tissue culture of Saposhnikovia divaricata （Turcz.） Schischk. In tissue culture with the root, stem segments, young leaf, cotyledonary node and axillary bud of Saposhnikovia divaricata （Turcz.） Schischk as explants, a lot of plantleles were obtained and the corresponding plant regeneration-system was established. The results showed that when use MS＋1.0 mg·L^-1 6-BA＋0.2 mg·L^-1 NAA as callus induction medium, the cotyledonary node had the highest bourgeon rate, and its callus was better than any others; MS＋2 mg·L^-1 6-BA＋0.4 mg·L^-1 NAA was the best adventitious buds induction medium, and the best adventitious buds induced condition was 3% sucrose as carbon source, illumination for 12-14 h·d^-1 and pH 5.8, The best rootage medium was 1/2 MS＋0.5 mg·L^-1 NAA.
基金The project supported by Singapore Institute for Clinical Sciences(SICS)A*STAR Singapore and BMRC Young Investigator Grant
文摘OBJECTIVE To investigate the effect of microRNA-32 on cold-induced thermogenesis and brown adipocyte energy metabolism.METHODS To apply the cold-induced thermogenesis model in mice,8-10 week old male C57Bl6 mice were placed within a 6℃fridge for 7d.Control microRNA inhibitor or miR-32 inhibitor(10mg·kg-1)was administered via intraperitoneal injection 16 hbefore the mice were placed in the fridge.Daily core body temperatures were taken using a rectal temperature probe.Mice were euthanized after 7dand brown adipose tissue(BAT),inguinal and epididymal white adipose tissue(WAT),skeletal muscle and liver tissue analysed for changes in morphology and gene expression.RESULTS miR-32 inhibition in vivoinhibits the emergence of beige cells,which function like BAT cells,within WAT.In silico prediction and gene ontology analysis identified Tob1 as a likely target gene of miR-32.miR-32 inhibition led to increased expression of Tob1 whilst mutation of target sequence abolished this effect.Expression of brown adipose markers such as Ucp1,Pgc1α,Pparαand Prdm16 were significantly reduced in inguinal white adipose tissue(P<0.05).There was also a significant decrease in serumfgf21 levels due to the inhibition of Fgf21 expression in BAT(P<0.05).p38/MAPK signalling in brown adipose tissue was also significantly inhibited within brown adipose tissue leading to decreased fgf21 expression and secretion.CONCLUSION Our study shows that miR-32 plays a crucial role in stimulating beige cell emergence by activating p38/MAPK signalling during cold thermogenesis.miR-32 may prove effective as a treatment for obesity by activating cold-induced thermogenesis leading to increased energy metabolism.
文摘Plant generation of TM-1 via tissue culture was established.The hypocotyledon sections as explants which were cultured in a series of improved MS media containing 0.05～0.10 mg·L-1 IAA,
基金Supported by Science and Technology Planning Projects of China during the 12th Five-year Plan-key Techniques of High Quality and High Efficiency Production of Fruit Trees(2014BAD16B07)Central Finance Forestry Science and Technology Extension Project(ZYLTKJTG2015017)National Featured Fruit Trees Root Stock Germplasm Resources Platform(Luntai)(NICGR2017-60)
文摘To study the effects of different concentrations of Abscisic Acid(ABA) on leaf tissue structure of Korla fragrant pear and lay the foundation for the cultivation and regulation of Korla fragrant pear. Using the paraffin section method, the leaf thickness, the epidermis thickness, the palisade tissue thickness and the sponge tissue thickness were measured; palisade spongy ratio, Cell Tightness(CT) and Cell Looseness(CL) were examined after treatments with exogenous ABA. Leaf thickness, leaf palisade spongy ratio and palisade tissue thickness increased significantly after exogenous ABA treatment compared with CK, while the effect on leaf epidermis was not obvious. The leaf thickness and palisade tissue thickness increased evidently after 70 mg · LABA treatment by 24.89% and 41.10%, respectively. The tissue structures of leaves were more compact, while CL was lower after 70 and 90 mg · LABA treatments. The effects of different concentrations of exogenous ABA could increase the leaf thickness, palisade tissue thickness of Korla fragrant pear and CT, reduced the thickness of spongy tissue and CL. Among those concentrations of exogenous ABA, the effect of spraying 70 mg · Lexogenous ABA was suitable for improving cold resistance of Korla fragrant pear.
基金supported by the National Institutes of Health ( OD / NICHD DP2HD083961)National Science Foundation ( CAREER CMMI-1254656)+2 种基金American Heart Association ( 13SDG17230047)March of Dimes ( MOD 5-FY14-111)Leo Q. Wan is a Pew Scholar in Biomedical Sciences ( PEW 00026185) ,supported by the Pew Charitable Trusts
文摘Cell and Tissue Engineering provides exciting opportunities for studying development and Disease.In this talk,we will focus on cell chirality,also known as handedness and left-right(LR)asymmetry,which is an intrinsic capability of the cell telling left from right(1)The development of the vertebrate body plan with left-right asymmetry requires the emerging chiral morphogenesis at multicellular levels at specific embryonic stages.Changes in orientation of the LR axis due to genetic or environmental factors can lead to malformations and disease.However,the concept of cell chirality has never studied in detail until the recent development of novel engineering tools[2-3].We demonstrate that the cultivation of cells on micropatterned 2D surfaces and in 3D graded hydrogels reveals an intrinsic cellular LR asymmetry,which is dependent of cell phenotype and actin cytoskeleton.With these new tools,we examine the role of cell chirality on the embryonic development of cardiac LR asymmetry [4] as well as the barrier function of endothelium layers [5].We find that Protein Kinase C(PKC)activation reverses the inherent chirality from clockwise to counter clockwise in engineering systems [4-5].Interestingly,activation of PKC signaling reverses the directional bias of chick cardiac C-looping [4].Mediating endothelial cell chirality can regulate the permeability of endothelial layers[5].Overall,our results strongly suggest critical roles of cell chirality in cardiovascular development and disease.
文摘Brain tissue is one of the softest parts of the human body,composed of white matter and grey matter.The mechanical behavior of the brain tissue plays an essential role in regulating brain morphology and brain function.Besides,traumatic brain injury(TBI)and various brain diseases are also greatly influenced by the brain's mechanical properties.Whether white matter or grey matter,brain tissue contains multiscale structures composed of neurons,glial cells,fibers,blood vessels,etc.,each with different mechanical properties.As such,brain tissue exhibits complex mechanical behavior,usually with strong nonlinearity,heterogeneity,and directional dependence.Building a constitutive law for multiscale brain tissue using traditional function-based approaches can be very challenging.Instead,this paper proposes a data-driven approach to establish the desired mechanical model of brain tissue.We focus on blood vessels with internal pressure embedded in a white or grey matter matrix material to demonstrate our approach.The matrix is described by an isotropic or anisotropic nonlinear elastic model.A representative unit cell(RUC)with blood vessels is built,which is used to generate the stress-strain data under different internal blood pressure and various proportional displacement loading paths.The generated stress-strain data is then used to train a mechanical law using artificial neural networks to predict the macroscopic mechanical response of brain tissue under different internal pressures.Finally,the trained material model is implemented into finite element software to predict the mechanical behavior of a whole brain under intracranial pressure and distributed body forces.Compared with a direct numerical simulation that employs a reference material model,our proposed approach greatly reduces the computational cost and improves modeling efficiency.The predictions made by our trained model demonstrate sufficient accuracy.Specifically,we find that the level of internal blood pressure can greatly influence stress distribution and determine the possible related damage behaviors.
文摘Current pharmacological therapies used in clinical practice for individuals with cardiac, hepatic, renal or pulmonary fibrosis do not show desirable effects; therefore, new targets of therapy are urgently required. Mitochon- dria play pivotal role in energy production, metabolism, serving as storage tanks of calcium ions and cell fate deter- mination. Recent results of our experiments and other authors＇ studies suggest that the electron transport chain dys- function, electron leakage increasing, the accumulation of fragmented mitochondria, and the impairment in the mi- tophagy system contribute to pathogenesis of tissue fibrosis. Mitochondria targeting compounds exert promise in trea- ring and attenuating the progress of these diseases, indicating potential strategies to target mitochondria in the treat- ment of tissue fibrosis.
基金supported in part by research grants from TATRC,College of Engineering at Berkeley and National Institute of Health
文摘Introductons The biophysical organization of extracellular matrix (ECM) plays an important role in tissue morphogenesis,remodeling and functions. In many types of tissues,e. g. ,blood vessel,nerve,heart,muscle,tendon and ligament,ECM has aniso-
文摘The ITRM of liver, one of the important indexes of tissue respiratory metabolism in yak, is higher than other tissues. The relationship of ITRM and time belongs to the equation y = aebt. The ITRM of each tissue in reciprocal yaks were significant(P＜0.05) lower than that of the domestic yaks which showed that the adaptability to hypoxia of the reciprocal yaks were more powerful than the domestic yaks.
