To explore the effect of non-uniform polarization on orbital angular momentum(OAM) in anisotropic medium, in this work investigated are the evolution of the spiral spectra and OAM densities of non-uniformly polarized ...To explore the effect of non-uniform polarization on orbital angular momentum(OAM) in anisotropic medium, in this work investigated are the evolution of the spiral spectra and OAM densities of non-uniformly polarized vortex(NUPV)beams in uniaxial crystals propagating orthogonal to the optical axis, and also the case of uniformly polarized vortex(UPV)beams with left-handed elliptical polarization. In the input plane, the NUPV beams present their spiral spectra of m-mode concentrated at m = l ± 1 modes rather than m = l mode, and reveal the relation among topological charge l, mode of spiral spectra m and the power weight value Rmexpressed by l=∑^(∞)_(m)=-∞Rm. is still satisfied for UPV beams in uniaxially anisotropic crystals, whereas for NUPV beams their relations are no longer valid owing to non-uniform polarization. Furthermore, the analysis indicates that the asymmetrical distribution of power weight of spiral spectra and the non-zero value in the sum of longitudinal OAM densities originate from the initial non-uniform polarization and anisotropy in uniaxial crystals rather than topological charges. In addition, the relation between spiral spectrum and longitudinal OAM density is numerically discussed. This work may provide an avenue for OAM-based communications,optical metrology, and imaging by varying the initial non-uniform polarization.展开更多
慢性乙型肝炎病毒(chronic hepatitis B virus,HBV)感染的自然病程通常分为4个阶段:免疫耐受期、乙肝e抗原(hepatitis B e antigen,HBeAg)阳性慢性乙型肝炎(chronic Hepatitis B,CHB)(即免疫清除期)、免疫控制期、HBeAg阴性CHB(即再活动...慢性乙型肝炎病毒(chronic hepatitis B virus,HBV)感染的自然病程通常分为4个阶段:免疫耐受期、乙肝e抗原(hepatitis B e antigen,HBeAg)阳性慢性乙型肝炎(chronic Hepatitis B,CHB)(即免疫清除期)、免疫控制期、HBeAg阴性CHB(即再活动期).根据HBeAg、乙肝病毒脱氧核糖核酸(HBV deoxyribonucleic acid,HBV DNA)、丙氨酸氨基转移酶(alanine aminotransferase,ALT)和肝脏组织学表现,将不适合上述任何一个阶段的不确定期患者分为以下四组:(1)免疫耐受期相关不确定期:其余指标符合免疫耐受期,但HBV DNA<10^(6)IU/mL或肝脏有显著炎症和纤维化;(2)免疫清除期相关不确定期:其余指标符合免疫清除期,但HBV DNA<2×10^(4)IU/mL或ALT 1-2倍正常值上限(the upper limits of normal,ULN);(3)免疫控制期相关不确定期:其余指标符合免疫控制期,但HBV DNA>2×10^(3)IU/mL或有显著炎症和纤维化;(4)再活动期相关不确定期:其余指标符合再活动期,但HBV DNA<2×10^(3)IU/mL或ALT 1-2 ULN.据统计我国约有7000万人感染了慢性HBV,其中约有2000-3000万是CHB患者.此外我国肝硬化和肝细胞癌(hepatocellular carcinoma,HCC)患者中,由HBV感染引起的比例分别为77%和84%.慢性HBV感染严重威胁着人民的生命健康并给国家医疗卫生体系带来沉重的经济负担.虽然现有指南建议动态监测这部分不确定期患者血清ALT和HBV DNA水平并评估肝脏组织学,但是否对这部分患者进行抗病毒治疗仍存有争议.本文主要介绍了CHB免疫控制期及与其相关不确定期患者的临床治疗现状,和对这部分患者进行抗病毒治疗的展望.展开更多
Background Medullary thyroid carcinoma （MTC） is a rare malignant tumour and usually difficult to diagnose with ultrasound. The aim of the study is to summarize the sonographic features of MTC and evaluate their diag...Background Medullary thyroid carcinoma （MTC） is a rare malignant tumour and usually difficult to diagnose with ultrasound. The aim of the study is to summarize the sonographic features of MTC and evaluate their diagnostic values.Methods We analyzed the sonographic features of 35 MTCs and 50 benign nodules with respect to nodular size,echogenecity, internal content, shape, height/width, border, peripheral halo, calcifications and colour flow pattern. The ratio of long to short axis, echogenecity, internal content and calcifications were also assessed in cervical lymph nodes.The differences in sonographic features between MTCs and benign nodules were analyzed with Chi square test. The diagnostic efficiency of each sonographic feature was determined.Results The main sonographic features of MTC were hypoechogenicity （including marked hypoechogenicity） （n=34,97%）, internal solid content （n=29, 83%）, taller than wide （n=34, 97%）, well defined border （n=24, 69%）,microcalcifications or macrocalcifications （n=23, 66%）. The echogenicity, internal content, shape, peripheral halo and calcifications were significantly different between these two groups, while the tall/wide, border, and pednodular and intranodular vascularisation were not significantly different. Among all the individual sonographic features, irregular shape had the highest diagnostic efficiency with a sensitivity of 51% and specificity of 92%. The combination of marked hypoechogenicity, microcalcifications, and irregular shape yielded a sensitivity of 77% and specificity of 86%.Conclusions The typical sonographic features of MTC are hypoechogenicity, predominantly solid, irregularly shaped with intranodular micro- or macro-calcifications. The combination of multiple sonographic features is helpful, but not definitive, for the diagnosis of MTC.展开更多
Non-alcoholic fatty liver disease(NAFLD)is associated with mutations in lipopolysaccharide-binding protein(LBP),but the underlying epigenetic mechanisms remain understudied.Herein,LBP^(-/-)rats with NAFLD were establi...Non-alcoholic fatty liver disease(NAFLD)is associated with mutations in lipopolysaccharide-binding protein(LBP),but the underlying epigenetic mechanisms remain understudied.Herein,LBP^(-/-)rats with NAFLD were established and used to conduct integrative targetingactive enhancer histone H3 lysine 27 acetylation(H3K27ac)chromatin immunoprecipitation coupled with high-throughput and transcriptomic sequencing analysis to explore the potential epigenetic pathomechanisms of active enhancers of NAFLD exacerbation upon LBP deficiency.Notably,LBP^(-/-)reduced the inflammatory response but markedly aggravated high-fat diet(HFD)-induced NAFLD in rats,with pronounced alterations in the histone acetylome and regulatory transcriptome.In total,1128 differential enhancer-target genes significantly enriched in cholesterol and fatty acid metabolism were identified between wild-type(WT)and LBP^(-/-)NAFLD rats.Based on integrative analysis,CCAAT/enhancer-binding proteinβ(C/EBPβ)was identified as a pivotal transcription factor(TF)and contributor to dysregulated histone acetylome H3K27ac,and the lipid metabolism gene SCD was identified as a downstream effector exacerbating NAFLD.This study not only broadens our understanding of the essential role of LBP in the pathogenesis of NAFLD from an epigenetics perspective but also identifies key TF C/EBPβand functional gene SCD as potential regulators and therapeutic targets.展开更多
Two-electron reduction of[N_(2)NBn]Ti^(Ⅳ)Cl2(3)gave a highly reactive[N_(2)N]Ti^(Ⅱ)species,which underwent C—O bond activation of THF(tetrahydrofuran)to generate[N2NBn]Ti^(Ⅳ)[O(CH2)4](4)through oxidative addition....Two-electron reduction of[N_(2)NBn]Ti^(Ⅳ)Cl2(3)gave a highly reactive[N_(2)N]Ti^(Ⅱ)species,which underwent C—O bond activation of THF(tetrahydrofuran)to generate[N2NBn]Ti^(Ⅳ)[O(CH2)4](4)through oxidative addition.The resulted Ti^(Ⅳ)-Csp^(3)bond in oxametallacyclo-hexane was tantamount to the elaborately-designed Ti-alkyl complexes,competent to activate intramolecular Csp^(2)-H bond,forming ortho-cyclometalated complex[N_(2)NCH_(2)C_(6)H_(4)]Ti^(Ⅳ)(O^(n)Bu)(5).Key intermediates were isolated and fully characterized by X-ray crystal-lography.Mechanistic studies revealed that the oxidative addition of C-O bond took place at Ti^(Ⅱ)-center via a radical intermediate,while a Csp^(2)-H bond activation proceeded byσ-bond metathesis with a kitelike four-centered Ti^(Ⅳ)-transition state.展开更多
AIM: To study the effects of crebanine on voltage-gated Na+ channels in cardiac tissues. METHODS: Single ventricular myocytes were enzymatically dissociated from adult guinea-pig heart. Voltage-dependent Na+ current w...AIM: To study the effects of crebanine on voltage-gated Na+ channels in cardiac tissues. METHODS: Single ventricular myocytes were enzymatically dissociated from adult guinea-pig heart. Voltage-dependent Na+ current was recorded using the whole cell voltage-clamp technique. RESULTS: Crebanine reversibly inhibited Na+ current with an IC50 value of 0.283 mmol?L-1(95% confidence range: 0.248-0.318 mmol?L-1). Crebanine at 0.262 mmol?L-1 caused a negative shift(about 12 mV) in the voltage-dependence of steady-state inactivation of Na+ current, and retarded its recovery from inactivation, but did not affect its activation curve. CONCLUSION: In addition to blocking other voltage-gated ion channels, crebanine blocked Na+ channels in guinea-pig ventricular myocytes. Crebanine acted as an inactivation stabilizer of Na+ channels in cardiac tissues.展开更多
The side effects of chemotherapy are mainly the poor control of drug release. Magnetic nanoparticles(MNPs) have super-paramagnetic behaviors which are preferred for biomedical applications such as in targeted drug del...The side effects of chemotherapy are mainly the poor control of drug release. Magnetic nanoparticles(MNPs) have super-paramagnetic behaviors which are preferred for biomedical applications such as in targeted drug delivery, besides, in magnetic recording, catalysis, and others. MNPs, due to high magnetization response, can be manipulated by the external magnetic fields to penetrate directly into the tumor, thus they can act as ideal drug carriers. MNPs also play a crucial role in drug delivery system because of their high surface-to-volume ratio and porosity. The drug delivery in tumor therapy is related to the sizes, shapes, and surface coatings of MNPs as carriers. Therefore, in this review, we first summarize the effects of the sizes, shapes, and surface coatings of MNPs on drug delivery, then discuss three types of drug release systems, i.e., p H-controlled, temperature-controlled, and magnetic-controlled drug release systems, and finally compare the principle of passive drug release with that of active drug release in tumor therapy.展开更多
Fruit yield is the most important horticultural trait of tomato.SIMBP21,a SEPALLATA subclass MADS-box gene has been reported to have functions in regulating pedicel abscission zone identity and development and control...Fruit yield is the most important horticultural trait of tomato.SIMBP21,a SEPALLATA subclass MADS-box gene has been reported to have functions in regulating pedicel abscission zone identity and development and controlling sepal size in tomato.However,we generated transgenic tomato plants which overexpress SIMBP21 and found the transformants displayed curly leaves,abnormally shaped flowers with twisted and opened stamens,reduced yield parameters,and small and light seeds.Our studies on the gain-of-function phenotype and gene expression level showed that its novel aspects played important roles in determining leaf morphology,flower and inflorescence architecture,and seed size,as well as the fruit yield.Overexpression of SIMBP21 in tomato resulted in curly leaves with fewer leaflets due to the regulation of the critical leaf polarity genes that cause an imbalance between the midvein adaxial-abaxial cell growth.Defects in the architecture of flowers and inflorescences resulted in reduced fruit set.Furthermore,we demonstrated that SIMBP21 plays its role through inhibiting the expression of the genes involved in the determination of seed development in tomato and SIMBP21 protein can interact with other MADS-box protein(SIAGL11,TAGL1 and SIMBP3)to control seed size.Thus,these results suggest that overexpression of SIMBP21 causes multiple types of damage to plant growth and development,especially fruit yield,in tomato.展开更多
The 60Co γ radiation effect on spherical open-porous polymethylphenylvinyl siloxane foam was studied in different atmospheres at room temperature. The physical and chemical behaviors of unirradiated and irradiated ma...The 60Co γ radiation effect on spherical open-porous polymethylphenylvinyl siloxane foam was studied in different atmospheres at room temperature. The physical and chemical behaviors of unirradiated and irradiated materials were studied by SEM, FTIR, TG (thermal gravity analysis), GC/MS(gas chromatography and mass spec -troscopy), etc. The present results indicate that the yields of gas products increase linearly with the dose increasing. Furthermore, some changes in material’s microscopic form, composition, structure and mechanical property were observed, but the maxi -mum thermal decomposition temperature of the sample alters little and the dose gives no effect on it.展开更多
基金supported by the Science and Technology Program of Sichuan Province, China (Grant No. 23NSFSC1097)。
文摘To explore the effect of non-uniform polarization on orbital angular momentum(OAM) in anisotropic medium, in this work investigated are the evolution of the spiral spectra and OAM densities of non-uniformly polarized vortex(NUPV)beams in uniaxial crystals propagating orthogonal to the optical axis, and also the case of uniformly polarized vortex(UPV)beams with left-handed elliptical polarization. In the input plane, the NUPV beams present their spiral spectra of m-mode concentrated at m = l ± 1 modes rather than m = l mode, and reveal the relation among topological charge l, mode of spiral spectra m and the power weight value Rmexpressed by l=∑^(∞)_(m)=-∞Rm. is still satisfied for UPV beams in uniaxially anisotropic crystals, whereas for NUPV beams their relations are no longer valid owing to non-uniform polarization. Furthermore, the analysis indicates that the asymmetrical distribution of power weight of spiral spectra and the non-zero value in the sum of longitudinal OAM densities originate from the initial non-uniform polarization and anisotropy in uniaxial crystals rather than topological charges. In addition, the relation between spiral spectrum and longitudinal OAM density is numerically discussed. This work may provide an avenue for OAM-based communications,optical metrology, and imaging by varying the initial non-uniform polarization.
文摘Background Medullary thyroid carcinoma （MTC） is a rare malignant tumour and usually difficult to diagnose with ultrasound. The aim of the study is to summarize the sonographic features of MTC and evaluate their diagnostic values.Methods We analyzed the sonographic features of 35 MTCs and 50 benign nodules with respect to nodular size,echogenecity, internal content, shape, height/width, border, peripheral halo, calcifications and colour flow pattern. The ratio of long to short axis, echogenecity, internal content and calcifications were also assessed in cervical lymph nodes.The differences in sonographic features between MTCs and benign nodules were analyzed with Chi square test. The diagnostic efficiency of each sonographic feature was determined.Results The main sonographic features of MTC were hypoechogenicity （including marked hypoechogenicity） （n=34,97%）, internal solid content （n=29, 83%）, taller than wide （n=34, 97%）, well defined border （n=24, 69%）,microcalcifications or macrocalcifications （n=23, 66%）. The echogenicity, internal content, shape, peripheral halo and calcifications were significantly different between these two groups, while the tall/wide, border, and pednodular and intranodular vascularisation were not significantly different. Among all the individual sonographic features, irregular shape had the highest diagnostic efficiency with a sensitivity of 51% and specificity of 92%. The combination of marked hypoechogenicity, microcalcifications, and irregular shape yielded a sensitivity of 77% and specificity of 86%.Conclusions The typical sonographic features of MTC are hypoechogenicity, predominantly solid, irregularly shaped with intranodular micro- or macro-calcifications. The combination of multiple sonographic features is helpful, but not definitive, for the diagnosis of MTC.
基金supported by the National Natural Science Foundation of China(81971875,82300661)Natural Science Foundation of Anhui province(2308085QH246)+3 种基金Natural Science Foundation of the Anhui Higher Education Institutions(KJ2021A0205)Basic and Clinical Cooperative Research Program of Anhui Medical University(2019xkjT002,2019xkjT022,2022xkjT013)Talent Training Program,School of Basic Medical Sciences,Anhui Medical University(2022YPJH102)National College Students Innovation and Entrepreneurship Training Program of China(202210366024)。
文摘Non-alcoholic fatty liver disease(NAFLD)is associated with mutations in lipopolysaccharide-binding protein(LBP),but the underlying epigenetic mechanisms remain understudied.Herein,LBP^(-/-)rats with NAFLD were established and used to conduct integrative targetingactive enhancer histone H3 lysine 27 acetylation(H3K27ac)chromatin immunoprecipitation coupled with high-throughput and transcriptomic sequencing analysis to explore the potential epigenetic pathomechanisms of active enhancers of NAFLD exacerbation upon LBP deficiency.Notably,LBP^(-/-)reduced the inflammatory response but markedly aggravated high-fat diet(HFD)-induced NAFLD in rats,with pronounced alterations in the histone acetylome and regulatory transcriptome.In total,1128 differential enhancer-target genes significantly enriched in cholesterol and fatty acid metabolism were identified between wild-type(WT)and LBP^(-/-)NAFLD rats.Based on integrative analysis,CCAAT/enhancer-binding proteinβ(C/EBPβ)was identified as a pivotal transcription factor(TF)and contributor to dysregulated histone acetylome H3K27ac,and the lipid metabolism gene SCD was identified as a downstream effector exacerbating NAFLD.This study not only broadens our understanding of the essential role of LBP in the pathogenesis of NAFLD from an epigenetics perspective but also identifies key TF C/EBPβand functional gene SCD as potential regulators and therapeutic targets.
基金support from the National Natural Science Foundation of China(Nos.21988101,21881220232,21811530004,21761132027,22071029,22201044,U19B6002)Key-Area Research and Development Program of Guangdong Province(2020B010188001).
文摘Two-electron reduction of[N_(2)NBn]Ti^(Ⅳ)Cl2(3)gave a highly reactive[N_(2)N]Ti^(Ⅱ)species,which underwent C—O bond activation of THF(tetrahydrofuran)to generate[N2NBn]Ti^(Ⅳ)[O(CH2)4](4)through oxidative addition.The resulted Ti^(Ⅳ)-Csp^(3)bond in oxametallacyclo-hexane was tantamount to the elaborately-designed Ti-alkyl complexes,competent to activate intramolecular Csp^(2)-H bond,forming ortho-cyclometalated complex[N_(2)NCH_(2)C_(6)H_(4)]Ti^(Ⅳ)(O^(n)Bu)(5).Key intermediates were isolated and fully characterized by X-ray crystal-lography.Mechanistic studies revealed that the oxidative addition of C-O bond took place at Ti^(Ⅱ)-center via a radical intermediate,while a Csp^(2)-H bond activation proceeded byσ-bond metathesis with a kitelike four-centered Ti^(Ⅳ)-transition state.
基金supported by the Natural Science Foundation of Yunnan Province(No.2002C0006Z)National Natural Science Foundation of China(No.81060371)
文摘AIM: To study the effects of crebanine on voltage-gated Na+ channels in cardiac tissues. METHODS: Single ventricular myocytes were enzymatically dissociated from adult guinea-pig heart. Voltage-dependent Na+ current was recorded using the whole cell voltage-clamp technique. RESULTS: Crebanine reversibly inhibited Na+ current with an IC50 value of 0.283 mmol?L-1(95% confidence range: 0.248-0.318 mmol?L-1). Crebanine at 0.262 mmol?L-1 caused a negative shift(about 12 mV) in the voltage-dependence of steady-state inactivation of Na+ current, and retarded its recovery from inactivation, but did not affect its activation curve. CONCLUSION: In addition to blocking other voltage-gated ion channels, crebanine blocked Na+ channels in guinea-pig ventricular myocytes. Crebanine acted as an inactivation stabilizer of Na+ channels in cardiac tissues.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.52072245,61771092,and 81702588)the Natural Science Foundation of Shanghai,China(Grant No.17ZR1419700)。
文摘The side effects of chemotherapy are mainly the poor control of drug release. Magnetic nanoparticles(MNPs) have super-paramagnetic behaviors which are preferred for biomedical applications such as in targeted drug delivery, besides, in magnetic recording, catalysis, and others. MNPs, due to high magnetization response, can be manipulated by the external magnetic fields to penetrate directly into the tumor, thus they can act as ideal drug carriers. MNPs also play a crucial role in drug delivery system because of their high surface-to-volume ratio and porosity. The drug delivery in tumor therapy is related to the sizes, shapes, and surface coatings of MNPs as carriers. Therefore, in this review, we first summarize the effects of the sizes, shapes, and surface coatings of MNPs on drug delivery, then discuss three types of drug release systems, i.e., p H-controlled, temperature-controlled, and magnetic-controlled drug release systems, and finally compare the principle of passive drug release with that of active drug release in tumor therapy.
基金the Training Program of Chongqing University Bioengineering College,China(0221001105301)the National Natural Science Foundation of China(31872121 and 31801870).
文摘Fruit yield is the most important horticultural trait of tomato.SIMBP21,a SEPALLATA subclass MADS-box gene has been reported to have functions in regulating pedicel abscission zone identity and development and controlling sepal size in tomato.However,we generated transgenic tomato plants which overexpress SIMBP21 and found the transformants displayed curly leaves,abnormally shaped flowers with twisted and opened stamens,reduced yield parameters,and small and light seeds.Our studies on the gain-of-function phenotype and gene expression level showed that its novel aspects played important roles in determining leaf morphology,flower and inflorescence architecture,and seed size,as well as the fruit yield.Overexpression of SIMBP21 in tomato resulted in curly leaves with fewer leaflets due to the regulation of the critical leaf polarity genes that cause an imbalance between the midvein adaxial-abaxial cell growth.Defects in the architecture of flowers and inflorescences resulted in reduced fruit set.Furthermore,we demonstrated that SIMBP21 plays its role through inhibiting the expression of the genes involved in the determination of seed development in tomato and SIMBP21 protein can interact with other MADS-box protein(SIAGL11,TAGL1 and SIMBP3)to control seed size.Thus,these results suggest that overexpression of SIMBP21 causes multiple types of damage to plant growth and development,especially fruit yield,in tomato.
基金Supported by the China Academy of Engineering Physics (CAEP Project No. 1999Z0503)
文摘The 60Co γ radiation effect on spherical open-porous polymethylphenylvinyl siloxane foam was studied in different atmospheres at room temperature. The physical and chemical behaviors of unirradiated and irradiated materials were studied by SEM, FTIR, TG (thermal gravity analysis), GC/MS(gas chromatography and mass spec -troscopy), etc. The present results indicate that the yields of gas products increase linearly with the dose increasing. Furthermore, some changes in material’s microscopic form, composition, structure and mechanical property were observed, but the maxi -mum thermal decomposition temperature of the sample alters little and the dose gives no effect on it.
