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The purpose of this study was to investigate the NOAEL of the nickel ion and provide with basic data for the biological evaluation of those medical devices containing nickel. Five groups SD rats were repeatedly exposed during 14 d respectively to nickel at first stage doses of 4.9, 3.7, 2.5 mg/(kg.d), and the second stage doses of 1.2, 0.25 mg/(kg.d) by the intravenous route. The results showed that the NOAEL of nickel ion is 0.25 mg/(kg.d) for SD rats, and the result was verified by subchronic systemic toxicity test of nickel alloy. The threshold of toxicological concern (TTC) of nickel is 150 μg/d (based on application of 100-fold uncertainty factor and a body weight of 60 kg)deduced by these data.
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Animals , Rats , Equipment and Supplies/adverse effects , Nickel/toxicity , No-Observed-Adverse-Effect Level , Rats, Sprague-Dawley , Risk AssessmentABSTRACT
Objective To evaluate the feasibility of optic nerve subarachnoid space in non?invasive qualitatively diagnosis of intracranial hypertension. Methods In this retrospective study, patients who received lumbar puncture from October 2009 to June 2015 were enrolled and divided into normal intracranial pressure group (41 cases) and intracranial hypertension group (39 cases). Optic nerve subarachnoid space width (SASW) behind ocular 3 mm (SASW?3),9 mm (SASW?9),and 15 mm (SASW?15) were measured on MRI and compared between groups. Chi?square test, t test and ROC analyses were used. Results SASW?3,SASW?9,and SASW?15 were (1.16±0.21), (0.98±0.21) and (0.92±0.17) mm in normal group and (1.46 ± 0.20), (1.29 ± 0.19) and (1.17 ± 0.20) mm in intracranial hypertension group, respectively. According to independent samples t test,SASW?3,SASW?9,and SASW?15 of intracranial hypertension group was significant larger than those at the same measured site of normal group (P<0.01). According to MedCalc analysis,Receive operating characteristic (ROC) area was 0.849 in SASW?3 and when the cut?off value was fixes as 1.19 mm,the sensibility and specificity were 94.9% and 63.4%,respectively. ROC area was 0.849 in SASW?9 and when the cut?off value was fixes as 1.10 mm, the sensibility and specificity were 84.6% and 78.0%,respectively. ROC area was 0.824 in SASW?15 and when the cut?off value was fixes as 1.06 mm,the sensibility and specificity were 69.2% and 80.5%,respectively. Conclusion SASW?9 can be used to screen and monitor the intracranial hypertension as a non?invasive tool.
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The purpose of this study was to investigate the cytotoxicity of the nickel ion and provide with basic data for the biological evaluation of those medical devices containing nickel. Seven cell lines were chosen. They were L929, h9c2(2-1), 293[HEK-293], hFOB1.19, THLE-3, H9 and IM-9 respectively. According to the principle of biological evaluation of medical devices, MTT method was chosen to test the cytotoxicity in different concentrations of nickel ion. For each cell line, the relative growth rate (RGR) was obtained and the cytotoxic grade was classified. Besides, IC50 values were calculated. As a result, it was found that the sensitivity was different among all cell lines. H9 was the most sensitive one, while the L929 was the most tolerant one. The concentration which is not above 1.25 mg/L was safe for all seven cell lines, because the cytotoxicity for all cells exposed in this concentration were not higher than grade 1. According to the criteria for medical devices, the concentrations not above 5 mg/L were safe for L929 cells. This result helps us to roughly assess the cytotoxicity and systematic toxicity caused by nickel contained in medical devices.
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Humans , Cell Line , Equipment and Supplies , HEK293 Cells , Ions , Toxicity , Nickel , ToxicityABSTRACT
Objective To identify the reliable reference genes for gene expression analysis of the pericarp and seed of Amomum villosum Lour. by using real-time fluorescence quantitative polymerase chain reaction ( qRT-PCR). Methods Using the fruits ( separated into peels and seeds) of A. villosum at three different developmental periods as the experimental material, 5 candidate reference genes (β-actin, EF-1α, GAPDH, PGK, TUA) with steady expression were screened out by the high throughout sequencing of transcriptome and expression profile data. The qRT-PCR technique was applied to study the expression levels of 5 candidate reference genes in different samples. The stability of the candidate reference genes were evaluated by GeNorm and NormFinder software. Results The 5 reference genes had different stabilities in the pericarp and seed of A. villosum Lour. at different development periods . The order of the steadiness of reference genes showed by GeNorm was EF-1α = TUA>PGK>GAPDH>β-actin. The results of NormFinder revealed that EF-1α was the most stable, followed by TUA, and the order of the other three genes was as same as the results of GeNorm. Conclusion EF-1αand TUA could be used as double reference genes for the normalization of gene expression in A. villosum fruits at different developmental periods by using qRT-PCR.
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This study was aimed to reveal the effects and molecular regulation mechanism of methyl jasmonate (Me-JA) on volatile terpenoids from Amomum villosum Lour. After the leaves and fruits of A momum villosum Lour. were treated with different concentrations of MeJA, the volatile terpenoids of fresh fruits from A . villosum Lour. were ex-tracted with microwave method and analyzed by GC-MS. Then, leaves and fruits treated with MeJA were sequenced by Illumina. The transcriptome data was analyzed by bioinformatic methods. The results showed that there were 20 and 33 volatile terpenoids detected in peels and seed groups, respectively. Contents of volatile terpenoids in peels and seed groups were both improved after 600 μmol·L-1 MeJA treating fruits for 24 h, such as bornyl acetate, cam-phor, borneol, and etc. While 200 μmol·L-1 MeJA treating different parts for 24 h can regulate the biosynthesis of some volatile terpenoids in peels differently. And 200 μmol·L-1 MeJA treating fruits can improve the content of ma-jor volatile terpenoids in seed groups. A total of 68 168 unigenes were obtained with de novo assembly, and 48 627 unigenes were annotated after comparison with public protein databases. Analysis of functional annotation against KEGG database showed that there were 208 unigenes closely related with metabolism of volatile terpenoids and 22 u-nigenes related with MYC2 transcription factors. It was concluded that MeJA can effectively regulate the metabolism of volatile terpenoids from A . villosum Lour. There were a lot of candidate genes related with the biosynthesis of volatile terpenoids obtained by analyzing the transcriptome data which also provided a large amount of data for the discovery and regulation of functional genes related with the biosynthesis of volatile terpenoids from A . villosum Lour.
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The dissolution of nickel from nitinol alloy under different extraction conditions was investigated when biological tests of nitinol medical devices were carried out. It discussed the equivalence of these extraction conditions and found the best extraction conditions. In the experiment, two brands of nitinol were chosen and extracted under different extraction conditions according to GB/T 16886-12. Plasma emission spectrometer was used to analyse the concentration of nickel in extract liquid. The results show that there is no equivalence among these extraction conditions for nitinol materials. And it is suggested that (37 +/- 1) degree C, (72 +/- 2) h could be used as normal extraction condition and (70 +/- 2) degrees C, (24 +/- 2) h as accelerated extraction condition.
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Alloys , Chemistry , Biocompatible Materials , Materials Testing , Nickel , Chemistry , Temperature , TitaniumABSTRACT
ISO 15189:2012Medical laboratories-Requirements for quality and competence was issued on November 1,2012,which replaced the second edition (ISO 15189:2007 Medical laboratoriesParticular requirements for quality and competence).A study on changes in new edition standard will facilitate medical laboratories,regulatory authorities,accreditation bodies to have a good understanding of requirements of this new edition.An implementation of new edition will assist medical laboratory to improve their management to continually meet requirements of international standards.To enable stakeholders mentioned above have a good understanding and application of this new edition,changes in new edition were discussed in depth in this article.
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Objective To study changes of dielectric properties of gastrocnemius caused by simulated weightlessness.Methods Male Sprague-Dawley rats tail suspended for 10 wk were observed together with its normal control.AC impedance of isolated gastrocnemius was measured with an impedance analyzer(Agilent 4294A).Effects of simulated weightlessness on electric properties of cells in isolated rat sural muscle were also observed by analyzing the dielectric numerical characters of the dielectric spectra,the Cole-Cole plots,spectrum of loss factor and loss tangent,as well as spectrum of conductivity imaginary part.Results It was found that simulated weightlessness could induce certain changes:both relative permittivity at low frequency ?L and relative permittivity increment ??,as well as conductivity at high frequency ?h and conductivity increment ?? were all reduced.The first characteristic frequency fC1 decreased,while the second characteristic frequency fC2 increased.Peak of loss factor,peak of loss tangent and the maximum of conductivity imaginary part were also reduced.Conclusion Changes of dielectric property of gastrocnemius induced by simulated weightlessness can be observed effectively by frequency domain impedance technique.
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At present, problems in nursing diagnoses include: omission of important diagnoses, inexact diagnoses, irregular writing of diagnoses, unclear differentiation of what is primary from what is secondary in the ordering of diagnoses, improper classification of relevant factors, neglect of psychological and social problems, confusion of problems involving cooperation and potential problems, and lack of conformity between diagnoses and admission evaluation. Measures for solving these problems include: change of concepts, improvement of the overall quality of the nursing personnel, enhancement of the awareness of quality, and reinforcement of assessment and guidance.
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Objective To study the electrophysiological properties of rat skeletal muscle within the frequency from 100Hz to 100MHz.Methods The AC impedance of rat sural muscle tissues was measured using the Agilent 4294A impedance analyzer, then the electrophysiological properties of the normal rat sural muscle cells were established in the respect of cell dielectric spectroscopy, Cole-Cole plots, spectrum of loss factor and loss tangent.Results (1) The dielectric response of rat sural muscle cells was frequency-dependent, such as increase in frequency caused decrease in permittivity. At the same time the conductivity trended to arise; (2) The dielectric parameters(?_L,?_h,?_L,?_h,△?″_ max,△tg?_ max,f_ C1,f_ C2) cell fiber parallel to the applied electric field differed from that cell fiber perpendicular to the applied electric field; (3) The effect of alternating current electric field on rat sural muscle cells showed a dielectric dispersion phenomenon, representing two characteristic frequency: the 1 st frequency(f_ C1(∥)=f_ C1(⊥)=1.02 kHz) and 2 nd frequency(f_ C2(∥)=59.31 kHz,f_ C2(⊥)=380.04kHz). Conclusion The method for studying the electrophysiological properties of rat skeletal muscle cells was established in the respect of the frequency domain,providing a possibility for investigating muscle fatigue in the future.