2.Establishment of mechanical middle ear model and the study of the acoustic characteristics of different ossicular prostheses.
Guan-Ping ZHANG ; Tao CU ; Ai-Xia WU ; Yong-Qi LI
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2007;42(2):130-134
OBJECTIVETo design a tool for evaluating the sound transmission function of ossicular prosthesis and explore the impacts of ossicular prosthesis bead area and the effects of the mass of ossicular prosthesis on the sound transmission function in mechanical middle ear model.
METHODSTwo latex membranes were used to represent the tympanic membrane and oval window membrane. The ossicular prosthesis was fitted between the artificial tympanic membrane and oval window membrane during the test. Pure tune signals were used to stimulate the vibration of tympanic membrane. The vibration of oval window membrane was recorded by a laser Doppler vibrometer. The ossicular transmission function was evaluated by comparing the vibration velocities of oval window membrane. Two groups of titanium ossicular prosthesis with different head area and mass respectively were fitted into a mechanical middle ear model to evaluate their sound transmission functions.
RESULTSThe feeling threshold curve of mechanical middle ear model (MMEM) was similar to the hearing threshold curve of normal person. The transmission function of the prosthesis with small head area was better than that of prostheses with large head area at frequencies 1500-4000 Hz. The small-massed prostheses functioned better at higher frequencies and the large-massed prostheses functioned better at lower frequencies. But small-massed prostheses functioned better as a whole.
CONCLUSIONSThe MMEM was an idea tool to evaluate the transmission functions of different ossicular prostheses. Both the head area and prosthesis mass had an influence on the transmission function of ossicular prosthesis. So while designing the ossicular prosthesis or performing ossiculoplasty, both the head area and prosthesis mass should he taken into consideration.
Acoustic Impedance Tests ; Acoustics ; Ear, Middle ; anatomy & histology ; Models, Anatomic ; Ossicular Prosthesis ; Prosthesis Design
3.Three-dimensional contrast-enhanced MR angiography in diagnosis of cerebral arteriovenous malformation
Qi LIU ; Jian-Ping LU ; Fei WANG ; Li WANG ; Jian-Ming TIAN ; Ai-Guo JIN ; Hao ZENG ;
Chinese Journal of Radiology 2001;0(08):-
Objective To evaluate the value of three-dimensional contrast-enhanced angiography (3D CE MRA) and MRI in the diagnosis and delineation of cerebral arteriovenous malformation(AVM). Methods Twenty-two cases of cerebral AVM examined by MRI and 3D CE,MRA.DSA was performed in 17 cases.A three-dimensional fast low angle shot (3D FLASH) was used for 3D CE MRA with Gd-DTPA dosage of 0.2 mmol per kilogram for body weight.The source images were subtracted from mask images and transferred to computer workstation using three-dimensional reconstruction.Results Among 22 cases, 19 showed typical AVM“flow void”signal on MR images.3D CE MRA clearly displayed the nidus,feeding artery and draining vein.All of the foci were above the cerebellum tentorium.13 located within one lobe, 3 exceeded one lobe and 3 situated in the deep of cerebrum.Feeding arteries were derived from single artery in 9 cases,and mixed supply in 10 cases.Draining veins diverted to sagittal sinus and/or sigmoid sinus in 6,deep cerebral veins in 8 and mixed in 5.In the 14 cases examined by both DSA and 3D CE MRA,3D CE MRA was superior to DSA in three-dimensional demonstration of the nidus,but inferior to DSA in demonstration of some details.3D CE MRA depicted 78.4% feeding arteries and 84.0% draining veins in addition,tiny pathologic blood vessels smaller than 1 centimeter were detected by DSA,but could not be found by 3D CE MRA and were only shown as hemorrhage lesions on MR images in 3 cases.Conclusion As a non-invasive technique,3D CE MRA combined with MRI is accurate in diagnosis and localization of cerebral AVM,and should be used as the first choice for those clinically suspected of AVM.But DSA remains needed for demonstration of details and tiny AVM.
4.The status and changes of soil nutrients in rhizosphere of cultivated Atractylodes lancea.
Lan-Ping GUO ; Lu-Qi HUANG ; Ai-Juan SHAO ; Dong-Mei LV ; Zhi-Gang WU
China Journal of Chinese Materia Medica 2005;30(19):1504-1507
OBJECTIVETo find the status and changes of the soil nutrients in rhizosphere of Atractylodes lancea.
METHODTotal nitrogen (total N), available K, available P, organic matter (ORG), available nitrogen and pH in rhizosphere soil of the wild growing A. lancea in 3 sites, MS, LT and MFS, and the cultivated ones with different ages in LT were detected.
RESULTThe contents of total nitrogen (total N), available K, available P, organic matter (ORG), available nitrogen and pH value in rhizosphere soil were significant different between MS, LT and MFS (P < 0.01). The results of the 6 detected parameters in MS were the lowest, in MFS were the highest and in LT were in the middle. The total N, ORG and available N in the cultivated A. lancea were lower than that in the wild ones (P < 0.01) and available P and pH value in the cultivated A. lancea were higher than that in wild ones (P < 0.01) and there was no difference in available K between the wild and cultivated ones in LT (P > 0.05); 3 available P in rhizosphere soil of the two years old A. lancea were higher than of the one year old A. lancea (P < 0.01) and there were no difference of total N, ORG, available N, available K and pH value in rhizosphere soil of A. lancea between one year and two years plant (P > 0.05).
CONCLUSIONIt is indicated that the growth of A. lancea in Mt. Mao is faced nutrient stress.
Atractylodes ; growth & development ; China ; Ecosystem ; Hydrogen-Ion Concentration ; Nitrogen ; analysis ; Organic Chemicals ; Phosphorus ; analysis ; Plants, Medicinal ; growth & development ; Potassium ; analysis ; Rhizome ; growth & development ; Soil ; analysis
5.Development of bovine blood lead component analysis standard reference materials.
Jian-ping LI ; Yi-qun WU ; Yong-gang ZHAO ; Qi-Hong ; Ai-jun CHI
Chinese Journal of Preventive Medicine 2008;42(6):410-413
OBJECTIVETo develop the first grade standard analytical reference material of bovine blood lead.
METHODSAccording to standards and technology specification of primary standard reference material (JJG1006-1994), ISO 17511, and volume-effect relationship, a bovine blood lead model was developed by adding acetate lead in the feed in dose of 2-5 mg x kg(-1) x d(-1). Cow blood was collected when blood lead concentration went up to low, medium and high concentration range (90-100, 190-200, 280-300 microg/L). Blood sample was kept in tube and frozen after irradiation. The samples were tested for homogeneity and stability. ID-MS method was used to measure the lead concentration through comparison with two standard lead samples from the USA NIST SRM 955b.
RESULTSSamples of the three lead concentrations showed uniformity by single factor analysis of variance (F = 0.61, 1.64, 0.28, respectively, P > 0.05) . After 14 months monitoring, the RSD was 0.85%, 1.05% and 0.49% (t = 0.787, 1.132, 0.854, respectively, P > 0.05). The characteristic and indefinite values were 102.4 +/- 5.5; 181.2 +/- 4.0; 304.5 +/- 3.9, respectively (unit: microg/L). The reproduction of the two USA NIST SRM 955b samples further showed our methods and procedures were correct. Our sample was stabile for four days at room temperature.
CONCLUSIONThe standard reference material of bovine in our research had reached the national standard material requirements.
Animal Feed ; Animals ; Blood Chemical Analysis ; standards ; Cattle ; Lead ; blood ; Male ; Models, Animal ; Reference Standards
6.Stage 3B Coats disease in a premature and low-birth-weight infant.
Hu-Ping SONG ; Hua AI ; Qi ZHU ; Chun-Ling LEI ; Jian-Zhou WANG ; Xiao-Qin LEI
Chinese Medical Journal 2012;125(20):3759-3760
7.Recombinant expression of Streptococcus pneumoniae comD/E/C genes and correlation of ComD/C with beta-lactam antibiotic resistance.
Huan FAN ; Ai-Hua SUN ; Xiao-Ping XIA ; Qi SUN ; Jie YAN
Journal of Zhejiang University. Medical sciences 2009;38(3):276-282
OBJECTIVETo construct prokaryotic expression systems of TCS genes comD/comE/comC of Streptococcus pneumoniae, and to determine the correlation of ComD and ComC with the drug resistance.
METHODSThe entire comD, comE and comC genes were amplified by PCR and their prokaryotic expression systems were established by routine genetic engineering technique. SDS-PAGE and Bio-Rad Agarose Image Analyzor was applied to measure the outputs of target recombinant proteins rComD, rComE and rComC. Rabbits were immunized with these recombinant proteins to prepare antisera. The resistance of S.pneumoniae strains to penicillin and cefotaxime was examined after ComD and ComC were blocked by antisera.
RESULTCompared with the reported sequences, similarities of nucleotide and amino acid sequences of the cloned comD, comE and comC genes were 98.4% approximately 99.3% and 99.1% approximately 100%, respectively. The constructed engineering bacteria E.coli BL21DE3(pET42a-comD), E.coli BL21DE3(pET42a-comE) and E.coli BL21DE3(pET42a-comC) were able to efficiently express the target recombinant proteins and the outputs of rComD, rComE and rComC were 28%, 25% and 35% of the total bacterial proteins, respectively. The double immunodiffusion titers of rabbit antisera against rComD, rComE or rComC were 1:4, 1:4 and 1:8, respectively. After the ComD and/or ComC were blocked by the antisera, the cefotaxime-sensitive S. pneumoniae strains became to resistant to antibiotics but there were no changes for cefotaxime-resistant strains and resistance to penicillin for all tested strains.
CONCLUSIONThe prokaryotic expression systems of S.pneumoniae comD/come/comC genes have been successfully constructed, and the study also indicates that both the ComD and ComC are involved in the drug resistance of S. pneumoniae to cefotaxime.
Animals ; Bacterial Proteins ; biosynthesis ; genetics ; Cefotaxime ; pharmacology ; Escherichia coli ; genetics ; metabolism ; Rabbits ; Recombinant Proteins ; biosynthesis ; genetics ; Recombination, Genetic ; Signal Transduction ; Streptococcus pneumoniae ; drug effects ; genetics ; beta-Lactam Resistance ; genetics
8.Free amino groups on the surface of chitosan nanoparticles and its characteristics.
Ai-Hua LIN ; Yi-Ming LIU ; Qi-Neng PING
Acta Pharmaceutica Sinica 2007;42(3):323-328
The relationship of free amino groups on the surface and the characteristics of chitosan nanoparticles (CS-NPs) prepared by ionic gelation method was investigated. Free amino groups on the surface of CS-NPs were determined by colloidal titration, and the effects of the amount of free amino groups and its ionizable level on the particle size, zeta potential, appearance, drug entrapment efficiency and drug release profile in vitro of CS-NPs were investigated. The result showed that the surface free amino groups reduced, the average size, zeta potential, stability of nanoparticles, and the drug release rate and degree all decreased while the drug entrapment efficiency was not affected with the increase of tripolyphosphate (TPP) concentration. With the increase of pH, the free amino groups could be deprotonated and the ionizable level was stepped down, correspondingly the particle size and zeta potential of CS-NPs decreased. Additionally, the drug release rate and degree were elevated in acid medium while descended in neutral or base medium. The amount and ionizable level of free amino groups on the surface are affected by the gelation degree and pH, which further affected the volume phase transitions (swelling/shrinking processes) of CS-NPs. The properties of CS-NPs have correlation with the surface free amino groups.
Amines
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chemistry
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Chitosan
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chemistry
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Hydrogen-Ion Concentration
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Microscopy, Electron, Transmission
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Nanoparticles
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chemistry
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ultrastructure
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Particle Size
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Polyphosphates
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chemistry
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Surface Properties
9.Expression deficiency of JWA enhanced DNA damage and delayed DNA repair in HeLa cells induced by benzo (a) pyrene exposure.
Zu-long LIU ; Deng-an GU ; Ai-ping LI ; Qi-zhan LIU ; Jian-wei ZHOU
Chinese Journal of Preventive Medicine 2006;40(2):84-87
OBJECTIVETo investigate the role of JWA gene in benzo (a) pyrene [B (a) P] induced DNA damage and repair effects in HeLa cells.
METHODSThe antisense JWA express vector (pEGFP-C1-asJWA) was constructed and stably transfected into HeLa cells. JWA deficient HeLa cells (asJWA-HeLa) was then screened and established. The general characteristics of asJWA-HeLa cells were investigated. DNA damage and repair cell culture model was conducted by treating the cells with 50 micromol/L B (a) P plus S9 for 3 hours and then the cells were maintained further 0, 1, 3, and 24 hours for DNA repairing. The damaged DNA was detected by single cell gel electrophoresis assay (comet assay).
RESULTSJWA deficient HeLa cells (with a 31% of JWA protein expression as compared with the control) were obtained successfully. Compared with the empty vector transfected cells (C1-HeLa) and the untransfected HeLa cells, asJWA-HeLa cells were more sensitive to B (a) P exposure and with a delayed DNA repair process.
CONCLUSIONThe JWA determined might function as a potential effective environmental responsive gene and actively participate the process of B (a) P exposure associated with intracellular signal pathways of DNA damage and repair.
Benzo(a)pyrene ; toxicity ; DNA Damage ; drug effects ; DNA Repair ; DNA-Formamidopyrimidine Glycosylase ; deficiency ; genetics ; Gene Expression ; HeLa Cells ; Heat-Shock Proteins ; deficiency ; genetics ; Humans ; Intracellular Signaling Peptides and Proteins ; deficiency ; genetics
10.Molecular mechanism and genetic basis of geoherbs.
Lu-Qi HUANG ; Lan-Ping GUO ; Juan HU ; Ai-Juan SHAO
China Journal of Chinese Materia Medica 2008;33(20):2303-2308
As products of interaction of time and space, geoherbs, which are essential parts of Chinese Materia Medica, were characterized in different morphology, unique habitat, continuous and changeable sites. The main fields in molecular mechanism of geoherbs focus on: biodiversity and molecular identification, genetic different and evolutionary genetics, geo-variation and environmental adaptation, germplasm and aimed genus choosing, expression and control of functional gene, gene transfer and bio-safety evaluation. The main tasks are to discover the genetic variation at molecular level, ascertain the molecular characteristics of geoherbs and the effect of environment on gene expression of geoherbs, confirm the genetic factors attribute to the forming of geoherbs, and find out the genetic basis of geoherbs at individual level and population level, respectively. This paper pointed out that the essential of geoherbs is continuers quantities variation at population level, geoherb's populations are different in gene frequency with the others'; geohersm are quantitative trait loci (QTL) controlled by multi - gene or combination with multiple-gene and major gene at individual level. It is very important to pay more attention to the scale effect of geoherbs, refer the theories and methods of quantities genetic, and concern more about the interaction of environment and gene in geoherbs' molecular mechanism research.
Drugs, Chinese Herbal
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adverse effects
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metabolism
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pharmacology
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Geography
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Plants, Medicinal
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classification
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genetics
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growth & development
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Quantitative Trait Loci