The present paper describes the ashing and atomization processes in silicon analysis by electrothermally atomised atomic absorption spectrometry(EAAAS) with an uncoat-ed graphite tube, a pyrolytically coated graphite ...The present paper describes the ashing and atomization processes in silicon analysis by electrothermally atomised atomic absorption spectrometry(EAAAS) with an uncoat-ed graphite tube, a pyrolytically coated graphite tube and a tungsten-coated graphitetube. The sensitivity and linear range of three graphite tubes were compared. By using optical temperature control accessory, the signals are enhanced by a factor of 2 and the germanium interferences in the determination of silicon are eliminated. The effects of time constant and carrier gas flow-rate on the determination of silicon were also tested. The sample can be directly analyzed in its aqueous solution without any pretreatment. The measurements of samples containing 0. 2 μg/mL and 0. 4 μg/mL silicon were run ten times and the variation coefficient is 4. 9% and 2.6%, respectively. The recovery tests for carboxyethyl germanium sesquioxide(Ge-132) synthesized and imported were performed, and the recoveries are 97. 0% and 110%, respectively. Keywords Carboxyethyl germanium sesquioxide, Electrothermally atomised atomic absorption spectrometry, Silicon展开更多
Low temperature plasma(LTP)technology has shown an outstanding application value in the pharmaceutical filed in recent ten years.This paper reviews the research advances in LTP,including its effects on enhancing or in...Low temperature plasma(LTP)technology has shown an outstanding application value in the pharmaceutical filed in recent ten years.This paper reviews the research advances in LTP,including its effects on enhancing or inhibiting drug activity,its combined use with drugs to treat cancers,its effects on the improvement of drug delivery system,its use in preparation of new inactivated virus vaccines,its use with mass spectrometry for rapid detection of drug quality,and the anti-tumor and sterilization effects of plasma-activated liquids.The paper also analyzes the challenges of LTP in the pharmaceutical filed,hoping to promote related research.展开更多
A modified low denaturing temperature PCR (LDT-PCR) method combined with DNA microarray technique is developed in our lab for quick and effective identification of various mutations in an 81 base pair region of Mycoba...A modified low denaturing temperature PCR (LDT-PCR) method combined with DNA microarray technique is developed in our lab for quick and effective identification of various mutations in an 81 base pair region of Mycobacterium Tuberculosis (MTB) ribosome RNA polymerase subunit B (rpoB) gene associated with rifampin resistance. By incurporation of wild type (wt) allele fragments that had been PCR amplified previously, the target PCR fragments coming from mutant clinical MTB samples were codenaturized with incorporated wt type allele fragment at 94°C and then let them randomly form matched structures (homoduplex) and allele mismatch-containing structures (heteroduplex), respectively, when the temperature cooled down to 70°C. After the temperature was raised to 80°C, the heteroduplex double stranded fragments were preferentially denatured and resulted in PCR amplification as well as fluorescence incurporation. Since the homoduplex fragments need a higher temperature to be denatured, they were kept in double-stranded status at that temperature and failed to be PCR amplified. By hybridization of LDT-PCR products with the probes spotted on microarray slides, the fluorescent signals representing the presence of gene mutations were detected. We have tested this method on 35 clinical MTB samples and obtained satisfied results.展开更多
Background:To study the energy pharmacological effects of chemical drugs.Methods:The energy pharmacological effects of chemical drugs were studied using a literature induction method.Results:Chemical drugs have energy...Background:To study the energy pharmacological effects of chemical drugs.Methods:The energy pharmacological effects of chemical drugs were studied using a literature induction method.Results:Chemical drugs have energy properties,which can be expressed in terms of cold,hot,warm,and cool.The energy properties of chemical drugs have energy pharmacological effects,which are related to the bond energy release and absorption of intermolecular chemical bonds,where the release of energy from chemical bonds indicates a warm-hot energy pharmacological effect and the absorption of energy indicates a cold energy pharmacological effect.The mechanisms of chemical drug energy may be related to the presence of temperature-sensitive ion channels in the body.Conclusion:Chemical drugs exhibit energy pharmacological effects.展开更多
Reversal of cancer drug resistance remains a critical challenge in chemotherapy.Mitochondria-targeted drug delivery has been suggested to mitigate drug resistance in cancer.To overcome the intrinsic limitations in con...Reversal of cancer drug resistance remains a critical challenge in chemotherapy.Mitochondria-targeted drug delivery has been suggested to mitigate drug resistance in cancer.To overcome the intrinsic limitations in conventional mitochondrial targeting strategies,we develop mitochondrial temperature-responsive drug delivery to reverse doxorubicin(DOX)resistance in lung cancer.Results demonstrate that the thermoresponsive nanocarrier can prevent DOX efflux and facilitate DOX accumulation and mitochondrial targeting in DOX-resistant tumors.As a consequence,thermoresponsive nanocarrier enhances the cytotoxicity of DOX and reverses the drug resistance in tumor-bearing mice.This work represents the first example of mitochondrial temperature-responsive drug delivery for reversing cancer drug resistance.展开更多
Stimuli-responsive polymers have undoubtedly been of great interest in the past decades due to a variety of their potential applications in biomedical territory. However, their non-degradability limits their in vivo a...Stimuli-responsive polymers have undoubtedly been of great interest in the past decades due to a variety of their potential applications in biomedical territory. However, their non-degradability limits their in vivo applications. Herein, we report a novel pH and temperature dual-stimuli responsive-poly（β-amino ester）. The pH/temperature sensitivities are interrelated and can be easily tuned by changing PEG-diacrylate chain length and the percentage of biamines in the feed ratio. These dual-responsive polymers are very useful in drug delivery. Reaction of methyl ether poly（ethylene glycol） （MPEG） and poly（β-amino ester） resulted in an amphiphilic MPEG-PBAE block copolymer which could form nanoparticles by self- assembly. A hydrophobic drug （DOX） was loaded in the self-assembled nanoparticles at low temperature without using organic solvents. The loaded drug was released very slowly and steadily at 37 ℃ under physiological conditions （pH 7.4）, but rapidly released from the micelles in weakly acidic environments （pH 6.4 and 5.0） for intracellular drug release. Thus, these poly（fl-amino ester） polymers constitute ideal drug carriers since their thermal sensitivity allows the drug loadings without using organic solvent and their pH sensitivity permits fast intracellular drug release.展开更多
文摘The present paper describes the ashing and atomization processes in silicon analysis by electrothermally atomised atomic absorption spectrometry(EAAAS) with an uncoat-ed graphite tube, a pyrolytically coated graphite tube and a tungsten-coated graphitetube. The sensitivity and linear range of three graphite tubes were compared. By using optical temperature control accessory, the signals are enhanced by a factor of 2 and the germanium interferences in the determination of silicon are eliminated. The effects of time constant and carrier gas flow-rate on the determination of silicon were also tested. The sample can be directly analyzed in its aqueous solution without any pretreatment. The measurements of samples containing 0. 2 μg/mL and 0. 4 μg/mL silicon were run ten times and the variation coefficient is 4. 9% and 2.6%, respectively. The recovery tests for carboxyethyl germanium sesquioxide(Ge-132) synthesized and imported were performed, and the recoveries are 97. 0% and 110%, respectively. Keywords Carboxyethyl germanium sesquioxide, Electrothermally atomised atomic absorption spectrometry, Silicon
基金supported by the National Natural Science Foundation of China(Grant No.51677146)Project of Independent Innovative Experiment for Postgraduates in Medicine in Xi’an Jiaotong University(Grant No.JSCX-2018-014)the Special Scientific Research Project Funds of Shaanxi Province(Grant No.18JK1102).
文摘Low temperature plasma(LTP)technology has shown an outstanding application value in the pharmaceutical filed in recent ten years.This paper reviews the research advances in LTP,including its effects on enhancing or inhibiting drug activity,its combined use with drugs to treat cancers,its effects on the improvement of drug delivery system,its use in preparation of new inactivated virus vaccines,its use with mass spectrometry for rapid detection of drug quality,and the anti-tumor and sterilization effects of plasma-activated liquids.The paper also analyzes the challenges of LTP in the pharmaceutical filed,hoping to promote related research.
文摘A modified low denaturing temperature PCR (LDT-PCR) method combined with DNA microarray technique is developed in our lab for quick and effective identification of various mutations in an 81 base pair region of Mycobacterium Tuberculosis (MTB) ribosome RNA polymerase subunit B (rpoB) gene associated with rifampin resistance. By incurporation of wild type (wt) allele fragments that had been PCR amplified previously, the target PCR fragments coming from mutant clinical MTB samples were codenaturized with incorporated wt type allele fragment at 94°C and then let them randomly form matched structures (homoduplex) and allele mismatch-containing structures (heteroduplex), respectively, when the temperature cooled down to 70°C. After the temperature was raised to 80°C, the heteroduplex double stranded fragments were preferentially denatured and resulted in PCR amplification as well as fluorescence incurporation. Since the homoduplex fragments need a higher temperature to be denatured, they were kept in double-stranded status at that temperature and failed to be PCR amplified. By hybridization of LDT-PCR products with the probes spotted on microarray slides, the fluorescent signals representing the presence of gene mutations were detected. We have tested this method on 35 clinical MTB samples and obtained satisfied results.
基金the National Natural Science Foundation of China(No.81072974).
文摘Background:To study the energy pharmacological effects of chemical drugs.Methods:The energy pharmacological effects of chemical drugs were studied using a literature induction method.Results:Chemical drugs have energy properties,which can be expressed in terms of cold,hot,warm,and cool.The energy properties of chemical drugs have energy pharmacological effects,which are related to the bond energy release and absorption of intermolecular chemical bonds,where the release of energy from chemical bonds indicates a warm-hot energy pharmacological effect and the absorption of energy indicates a cold energy pharmacological effect.The mechanisms of chemical drug energy may be related to the presence of temperature-sensitive ion channels in the body.Conclusion:Chemical drugs exhibit energy pharmacological effects.
基金We are grateful to Beijing Natural Science Foundation(7212212)National Natural Science Foundation of China(11875269 and 21574136)Hundred Talents Program of CAS for financial support。
文摘Reversal of cancer drug resistance remains a critical challenge in chemotherapy.Mitochondria-targeted drug delivery has been suggested to mitigate drug resistance in cancer.To overcome the intrinsic limitations in conventional mitochondrial targeting strategies,we develop mitochondrial temperature-responsive drug delivery to reverse doxorubicin(DOX)resistance in lung cancer.Results demonstrate that the thermoresponsive nanocarrier can prevent DOX efflux and facilitate DOX accumulation and mitochondrial targeting in DOX-resistant tumors.As a consequence,thermoresponsive nanocarrier enhances the cytotoxicity of DOX and reverses the drug resistance in tumor-bearing mice.This work represents the first example of mitochondrial temperature-responsive drug delivery for reversing cancer drug resistance.
基金financially supported by the National Natural Science Foundation of China(No.51402099)Education Foundation of Hubei Province(No.T201521)the Science Foundation from Hubei Polytechnic University(Nos.12xjz08R and 801-8596)
文摘Stimuli-responsive polymers have undoubtedly been of great interest in the past decades due to a variety of their potential applications in biomedical territory. However, their non-degradability limits their in vivo applications. Herein, we report a novel pH and temperature dual-stimuli responsive-poly（β-amino ester）. The pH/temperature sensitivities are interrelated and can be easily tuned by changing PEG-diacrylate chain length and the percentage of biamines in the feed ratio. These dual-responsive polymers are very useful in drug delivery. Reaction of methyl ether poly（ethylene glycol） （MPEG） and poly（β-amino ester） resulted in an amphiphilic MPEG-PBAE block copolymer which could form nanoparticles by self- assembly. A hydrophobic drug （DOX） was loaded in the self-assembled nanoparticles at low temperature without using organic solvents. The loaded drug was released very slowly and steadily at 37 ℃ under physiological conditions （pH 7.4）, but rapidly released from the micelles in weakly acidic environments （pH 6.4 and 5.0） for intracellular drug release. Thus, these poly（fl-amino ester） polymers constitute ideal drug carriers since their thermal sensitivity allows the drug loadings without using organic solvent and their pH sensitivity permits fast intracellular drug release.
