Objective Study of bupropion hydrochloride gel matrix sustained release tablet and the preparation method, test the skeleton material of hydroxypropyl methyl cellulose influencing drug release for evaluation, explore ...Objective Study of bupropion hydrochloride gel matrix sustained release tablet and the preparation method, test the skeleton material of hydroxypropyl methyl cellulose influencing drug release for evaluation, explore the preparation of sustained release tablets of optimization method. Method With hydroxypropyl methyl cellulose as skeleton material, according to the different prescription preparation of bupmpion hydrochloride sustained release tablets. Different HPMC viscosity, Consumption, particle size, compression pressure and slurry rotational speed and other factors, analysis the influence on drug release rate.Through the release of test evaluation of sustained release effect, and the preliminary study on the drug release characteristic. With hydroxypropyl methyl cellulose ( HPMC ) as skeleton material, with citric acid citrate as a porogenic agent, direct powder tabletting method of bupropion hydrochloride sustained release tablets; by using single factor and orthogonal experiment method to investigate HPMC different viscosity, different Consumption, different particle size, different compression pressure, different pulp rotational speed and other factors on the release of delivery rate. Result Select HPMC-K100M for bupropion hydrochloride sustained release tablets of the skeleton materials; reinforcing materials of high viscosity HPMC K100M and main drug quality ratio of 1: 1; HPMC particle diameter of 125p m, make use of these conditions to preparation of bupropion hydrochloride sustained release tablets for optimal prescription conditions. Conclusion bupropion hydroehloride sustained release tablets on the drug release rate is mainly affected by HPMC viscosity and dosage effect. Along with the tablet of HPMC viscosity increased, the drug is released slowly. HPMC viscosity, dosage on the drug release rate has significant influence.展开更多
The peripheral nervous system is able to regenerate after injury, and regeneration is associated with the expression of many genes and proteins. MicroRNAs are evolutionarily conserved, small, non-coding RNA molecules ...The peripheral nervous system is able to regenerate after injury, and regeneration is associated with the expression of many genes and proteins. MicroRNAs are evolutionarily conserved, small, non-coding RNA molecules that regulate gene expression at the level of translation. In this paper, we focus on the identification and functional annotation of novel microRNAs in the proximal sciatic nerve after rat sciatic nerve transection. Using Solexa sequencing, computational analysis, and quantitative reverse transcription PCR verification, we identified 98 novel microRNAs expressed on days 0, 1, 4, 7, and 14 after nerve transection. Furthermore, we predicted the target genes of these microRNAs and analyzed the biological processes in which they were involved. The identified biological processes were consistent with the known time-frame of peripheral nerve injury and repair. Our data provide an important resource for further study of the role and regulation of microRNAs in peripheral nerve injury and regeneration.展开更多
Ryanodine receptors(Ry Rs) are the calcium release channels of sarcoplasmic reticulum(SR) that provide the majority of calcium ions(Ca2+) necessary to induce contraction of cardiac and skeletal muscle cells.In their i...Ryanodine receptors(Ry Rs) are the calcium release channels of sarcoplasmic reticulum(SR) that provide the majority of calcium ions(Ca2+) necessary to induce contraction of cardiac and skeletal muscle cells.In their intracellular environment,Ry R channels are regulated by a variety of cytosolic and luminal factors so that their output signal(Ca2+) induces finely-graded cell contraction without igniting cellular processes that may lead to aberrant electrical activity(ventricular arrhythmias) or cellular remodeling.The importance of Ry R dysfunction has been recently highlighted with the demonstration that point mutations in RYR2,the gene encoding for the cardiac isoform of the Ry R(Ry R2),are associated with catecholaminergic polymorphic ventricular tachycardia(CPVT),an arrhythmogenic syndrome characterized by the development of adrenergically-mediated ventricular tachycardia in individuals with an apparently normal heart.Here we summarize the state of the field in regards to the main arrhythmogenic mechanisms triggered by Ry R2 channels harboring mutations linked to CPVT.Most CPVT mutations characterized to date endow Ry R2 channels with a gain of function,resulting in hyperactive channels that release Ca2+ spontaneously,especially during diastole.The spontaneous Ca2+ release is extruded by the electrogenic Na+/Ca2+ exchanger,which depolarizes the external membrane(delayed afterdepolarization or DAD) and may trigger untimely action potentials.However,a rare set of CPVT mutations yield Ry R2 channels that are intrinsically hypo-active and hypo-responsive to stimuli,and it is unclear whether these channels release Ca2+ spontaneously during diastole.We discuss novel cellular mechanisms that appear more suitable to explain ventricular arrhythmias due to Ry R2 loss-of-function mutations.展开更多
Objective: To deliver cells deep into injectable calcium phosphate cement(CPC) through alginate-chitosan(AC) microcapsules and investigate the biological behavior of the cells released from microcapsules into the...Objective: To deliver cells deep into injectable calcium phosphate cement(CPC) through alginate-chitosan(AC) microcapsules and investigate the biological behavior of the cells released from microcapsules into the CPC.Methods: Mouse osteoblastic MC3T3-E1 cells were embedded in alginate and AC microcapsules using an electrostatic droplet generator.The two types of cell-encapsulating microcapsules were then mixed with a CPC paste.MC3T3-E1 cell viability was investigated using a Wst-8 kit,and osteogenic differentiation was demonstrated by an alkaline phosphatase(ALP) activity assay.Cell attachment in CPC was observed by an environment scanning electron microscopy.Results: Both alginate and AC microcapsules were able to release the encapsulated MC3T3-E1 cells when mixed with CPC paste.The released cells attached to the setting CPC scaffolds,survived,differentiated,and formed mineralized nodules.Cells grew in the pores concomitantly created by the AC microcapsules in situ within the CPC.At Day 21,cellular ALP activity in the AC group was approximately four times that at Day 7 and exceeded that of the alginate microcapsule group(P0.05).Pores formed by the AC microcapsules had a diameter of several hundred microns and were spherical compared with those formed by alginate microcapsules.Conclusions: AC microcapsule is a promising carrier to release seeding cells deep into an injectable CPC scaffold for bone engineering.展开更多
文摘Objective Study of bupropion hydrochloride gel matrix sustained release tablet and the preparation method, test the skeleton material of hydroxypropyl methyl cellulose influencing drug release for evaluation, explore the preparation of sustained release tablets of optimization method. Method With hydroxypropyl methyl cellulose as skeleton material, according to the different prescription preparation of bupmpion hydrochloride sustained release tablets. Different HPMC viscosity, Consumption, particle size, compression pressure and slurry rotational speed and other factors, analysis the influence on drug release rate.Through the release of test evaluation of sustained release effect, and the preliminary study on the drug release characteristic. With hydroxypropyl methyl cellulose ( HPMC ) as skeleton material, with citric acid citrate as a porogenic agent, direct powder tabletting method of bupropion hydrochloride sustained release tablets; by using single factor and orthogonal experiment method to investigate HPMC different viscosity, different Consumption, different particle size, different compression pressure, different pulp rotational speed and other factors on the release of delivery rate. Result Select HPMC-K100M for bupropion hydrochloride sustained release tablets of the skeleton materials; reinforcing materials of high viscosity HPMC K100M and main drug quality ratio of 1: 1; HPMC particle diameter of 125p m, make use of these conditions to preparation of bupropion hydrochloride sustained release tablets for optimal prescription conditions. Conclusion bupropion hydroehloride sustained release tablets on the drug release rate is mainly affected by HPMC viscosity and dosage effect. Along with the tablet of HPMC viscosity increased, the drug is released slowly. HPMC viscosity, dosage on the drug release rate has significant influence.
基金supported by the National High Technology Research and Development Program of China (Grant No. 2006AA02A128)the National Natural Science Foundation of China (Grant No. 30870811)+1 种基金the Jiangsu Provincial Natural Science Foundation (Grant No. BK2008010)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘The peripheral nervous system is able to regenerate after injury, and regeneration is associated with the expression of many genes and proteins. MicroRNAs are evolutionarily conserved, small, non-coding RNA molecules that regulate gene expression at the level of translation. In this paper, we focus on the identification and functional annotation of novel microRNAs in the proximal sciatic nerve after rat sciatic nerve transection. Using Solexa sequencing, computational analysis, and quantitative reverse transcription PCR verification, we identified 98 novel microRNAs expressed on days 0, 1, 4, 7, and 14 after nerve transection. Furthermore, we predicted the target genes of these microRNAs and analyzed the biological processes in which they were involved. The identified biological processes were consistent with the known time-frame of peripheral nerve injury and repair. Our data provide an important resource for further study of the role and regulation of microRNAs in peripheral nerve injury and regeneration.
基金supported by grants from the US National Institutes of Health(RO1-HL55438,PO1-HL094291,and RO1-108175 to HHV)a recipient of a fellowship from the Panamanian Ministry of Science
文摘Ryanodine receptors(Ry Rs) are the calcium release channels of sarcoplasmic reticulum(SR) that provide the majority of calcium ions(Ca2+) necessary to induce contraction of cardiac and skeletal muscle cells.In their intracellular environment,Ry R channels are regulated by a variety of cytosolic and luminal factors so that their output signal(Ca2+) induces finely-graded cell contraction without igniting cellular processes that may lead to aberrant electrical activity(ventricular arrhythmias) or cellular remodeling.The importance of Ry R dysfunction has been recently highlighted with the demonstration that point mutations in RYR2,the gene encoding for the cardiac isoform of the Ry R(Ry R2),are associated with catecholaminergic polymorphic ventricular tachycardia(CPVT),an arrhythmogenic syndrome characterized by the development of adrenergically-mediated ventricular tachycardia in individuals with an apparently normal heart.Here we summarize the state of the field in regards to the main arrhythmogenic mechanisms triggered by Ry R2 channels harboring mutations linked to CPVT.Most CPVT mutations characterized to date endow Ry R2 channels with a gain of function,resulting in hyperactive channels that release Ca2+ spontaneously,especially during diastole.The spontaneous Ca2+ release is extruded by the electrogenic Na+/Ca2+ exchanger,which depolarizes the external membrane(delayed afterdepolarization or DAD) and may trigger untimely action potentials.However,a rare set of CPVT mutations yield Ry R2 channels that are intrinsically hypo-active and hypo-responsive to stimuli,and it is unclear whether these channels release Ca2+ spontaneously during diastole.We discuss novel cellular mechanisms that appear more suitable to explain ventricular arrhythmias due to Ry R2 loss-of-function mutations.
基金supported by the National Natural Science Foundation of China(No.30772447)the Talent Introduction Project of Peking University Health Science Center(No.bmu2009139),China
文摘Objective: To deliver cells deep into injectable calcium phosphate cement(CPC) through alginate-chitosan(AC) microcapsules and investigate the biological behavior of the cells released from microcapsules into the CPC.Methods: Mouse osteoblastic MC3T3-E1 cells were embedded in alginate and AC microcapsules using an electrostatic droplet generator.The two types of cell-encapsulating microcapsules were then mixed with a CPC paste.MC3T3-E1 cell viability was investigated using a Wst-8 kit,and osteogenic differentiation was demonstrated by an alkaline phosphatase(ALP) activity assay.Cell attachment in CPC was observed by an environment scanning electron microscopy.Results: Both alginate and AC microcapsules were able to release the encapsulated MC3T3-E1 cells when mixed with CPC paste.The released cells attached to the setting CPC scaffolds,survived,differentiated,and formed mineralized nodules.Cells grew in the pores concomitantly created by the AC microcapsules in situ within the CPC.At Day 21,cellular ALP activity in the AC group was approximately four times that at Day 7 and exceeded that of the alginate microcapsule group(P0.05).Pores formed by the AC microcapsules had a diameter of several hundred microns and were spherical compared with those formed by alginate microcapsules.Conclusions: AC microcapsule is a promising carrier to release seeding cells deep into an injectable CPC scaffold for bone engineering.