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@#Objective To develop and verify a reversed phase high-performance liquid chromatography method for the determination of the purity of recombinant Mycobacterium tuberculosis(Mtb)Ag85b protein stock solution.Methods Fourfactor,three-level orthogonal test was designed,with the area,trailing factor,peak area and peak area RSD as the evaluation indexes to explore the optimal detection conditions. The methodology verification of specificity,linear range,precision and durability was conducted in accordance with the general principles of Chinese Pharmacopoeia(Volume Ⅳ,2020 edition)9101.Results The results of all the evaluation indexes were good when the elution ratio of organic phase was30% ～ 95%,the detection temperature was 35 ℃,the sample volume was 3 μg,and the elution time of 95% organic phase was 15 min. The method had the linear correlation coefficient(R2)of 0. 998 5,the linear range of 1. 8 ～ 4. 2 μg,the reproducibility RSD of 0. 01%,and the intermediate precision RSD of 0. 16%,with good durability under slight changes of column temperature and flow rate.Conclusion The reversed phase high-performance liquid chromatography method for the purity determination of recombinant Mtb Ag85b protein stock solution was developed,which has good specificity,precision and durability,and can be used for the quality control of recombinant Mtb Ag85b protein stock solution.
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@#Objective To compare the concentration and protein relative yield of insect fusion antifreeze protein EGFP-OcAFP4 extracted by low temperature ethanol method,ammonium sulfate salting-out method and isoelectric point method. Methods By screening different concentrations of ethanol(5%-65%)and ammonium sulfate(0. 2-3. 0 mol/L)and different the pH values(5. 6,5. 4,5. 2,5. 0,4. 8,4. 7,4. 6,4. 5,4. 4),EGFP-OcAFP4 was extracted from the supernatant of the induced expression solution of recombinant plasmid pET28a-EGFP-OcAFP4,and detected for the purity and protein relative yield.Results When prepared by ethanol method,EGFP-OCAFP4 had the highest purity of 86. 21% at the ethanol final concentration of 30%,and the relative yield was 6. 89%;when it was prepared by ammonium sulfate salting-out,the purity was up to 42. 33% with the protein relative yield of 30. 83% at the ammonium sulfate final concentration of 2. 0 mol/L;the purity of EGFP-OcAFP4 extracted by isoelectric point method with pH of 5. 0 was the highest 15. 46%,and the relative yield was 11. 97%. Conclusion Low temperature ethanol method,ammonium sulfate salting-out and isoelectric point method can all be used for the extraction of EGFP-OcAFP4,but low temperature ethanol method and ammonium sulfate salting-out method have higher extraction purity and protein relative yield,which are more suitable for the extraction of EGFP-OcAFP4
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@#Objective To develop and validate size exclusion column-high performance liquid chromatography(SEC-HPLC)for determination of the purity of bulk material of freeze-dried rabies vaccine for human use.Methods Chromatography column TSK-gel G6000PW_(XL)(7.8 mm × 30 cm,13 μm)was used for the determination(column temperature 30 ℃)with mobile phase of 0.1 mol/L PB buffer(pH 7.8)at a flow rate of 0.5 mL/min.The detection wavelength was 280 nm and injection volume was 20 μL.The method was validated for system suitability,specificity,precision and durability and determined for detection limit and quantitation limit,which was applied to analyze bulk material purity of freeze-dried rabies vaccine for human use of 3 batches of Vero cells and 1 batch of human diploid cells.Results The resolution of target protein spectrum peak of bulk material of reference sample and freeze-dried rabies vaccine for human use prepared with two substrates was more than 1.5 with a tailing factor less than 1.5;The blank solvent showed no absorption peak at the position of target protein peak with no interference in the determination;The RSDs of retention time and peak area in precision verification were both less than 2.0%;The quantitative limit was 10 μg/mL,and the detection limit was 4 μg/mL;The reference sample was injected three times continuously at three different detection wavelengths of 278,280 and 282 nm,and the RSDs of retention time and peak area were also less than 2.0%.The purity of 4 batches of freeze-dried rabies vaccine bulk material for human use was all more than 97%.Conclusion The developed SEC-HPLC for determination of the purity of freeze-dried rabies vaccine bulk material for human use showed good specificity,precision and durability,which provided a reliable method for the quality control of human rabies vaccine.
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@#Objective To prepare the 1st batch of national standard of recombinant trypsin in order to standardize and improve the quality of recombinant trypsin.Methods Enzyme-substrate identification,HPLC identification,N-terminal sequencing and TOF-MS were used to confirm the property and structure of recombinant trypsin;the purity was determined by HPLC;according to the methods in Chinese Pharmacopoeia(Volume Ⅲ 3603,2020 edition),the specific activity of the candidate standard was determined,and the stability and uniformity were investigated.Results The structure of recombinant trypsin was confirmed,and the specific activity of the 1 st batch of national standard of recombinant trypsin was 5 169 U/mg,containing 80% β-trypsin and 9% α-trypsin.The RSD of purity of α,β-trypsin and retention time of 12 candidate standards were all less than 2.0%.The purity of α,β-trypsin showed no obvious decrease stored at 25 ℃ and relative humidity(RH) 80% for 10 d,while the purity of β-trypsin decreased slightly and the purity of α-trypsin increased slightly stored at 40℃ and RH 80% for 10 d.The purity of β-trypsin decreased slightly when exposed to light(4 000 lx) for 10 d.Conclusion The national standard of recombinant trypsin with accurate structure and high purity was prepared,which can be used for system suitability test of the purity determination.
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@#Objective Establish quality control methods for critical quality attribute of bispecific antibody against programmed cell death protein 1(PD-1)/cytotoxic T-lymphocyte-associated protein 4(CTLA-4).Methods The biological activity of PD-1 target was determined by reporter gene assay,and the competitive binding activity of CTLA-4 target was determined by flow cytometry;The antibody molecular size variants were controlled by reducing/non-reducing capillary electrophoresis-sodium dodecyl sulfonate(CE-SDS) and size exclusion chromatography-high performance liquid chromatography(SEC-HPLC);Charge heterogeneity was determined by imaging capillary isoelectric focusing electrophoresis(iCIEF);Bispecific anti-PD-1/CTLA-4 antibody was identified by peptide map analysis;Glycosylation was analysed by high performance liquid chromatography(HPLC)Results The concentration for 50% of maximal effect(EC_(50)) of PD-1target was(6.91±0.78) nmol/L,and the relative biological potency to the reference was(103.50±13.08)% with the RSD of 12.64%;The EC_(50) of CTLA-4 target activity was(0.35±0.28) nmol/L,and the relative biological potency was(99.30±9.15)% with the RSD of 8.32%.The percentage of peak area of light chain and heavy chain of reducing CE-SDS was(98.86±0.02)%.The main peak area percentage of non-reducing CE-SDS was(93.07±0.13)%,fragment percentage was(4.44±0.13)%,and polymer percentage was(2.49±0.15)%.The peak area percentage of SEC-HPLC monomer and polymer were(97.20±0.01)% and(2.68±0.01)%,respectively.The area percentage of peak A group,peak B group,peak C group and peak D group were(38.43±0.54)%,(43.26±0.32)%,(11.31±0.14)% and(7.00±0.17)%,respectively.Peptide mapping showed the specific spectrum of the bispecific anti-PD-1/CTLA-4 antibody,which could be adopted for identification test.The highest proportion of glycotype was GOF,with a content of(41.06±0.11)%,There were three types of glycan containing sialic acid,namely G2F+G1F-NANA,G2F-NANA and G2F-2NANA,with the content of(12.44±0.12)%,(12.00±0.05)% and(5.37±0.05)%,respectively.The total content of glycan containing sialic acid was(29.80±0.20)%.Conclusion The critical quality attributes of bispecific anti-PD-1/CTLA-4 antibody were studied and the corresponding quality control methods were established to ensure its safety,effectiveness and quality control,which provides a reference for the quality control methods and strategies of this type of monoclonal antibody products.
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The purity of 4,4′-dimethoxy-5,6,5′,6′-bis (methylenedioxy)-2′-morpholine methylenebiphenyl-2-methyl formate methanesulfonate (IMH), a new drug for fatty liver treatment, was determined through differential scanning calorimetry (DSC). Analysis of two-factor non repeatability method was performed in the investigation the effects of two factors (heating rate and sample weight) on purity determination. The DSC experimental parameters were optimized as follows: heating rate was 10 ℃·min-1, temperature range was 150-300 ℃, sample weight was 2.0-4.1 mg, and N2 flow rate was 80 mL·min-1. The linear correlation coefficient (r) of this DSC method was 0.999 8. The RSD value (n = 6) of precision was 0.03%. The standard value and uncertainty of the purity results of the multiple batches of IMH drugs were (99.74 ± 0.29)%, (99.91 ± 0.28)%, (99.90 ± 0.28)%, and (99.81 ± 0.28)% with inclusion factor (K) of 2 and confidence probability (P) of 0.95. The results were basically consistent with the results of the mass balance method. The DSC mehod is a simple, rapid and accurate method, and provides a new reference method for determining the purity of IMH drugs, improves the accuracy and reliability of purity determination.
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Objective To explore the extraction and purification method of Kupffer and hepatic stellate cells from mouse liver and provide references and suggestions for the separation and extraction method ology of primary non-parenchymal cells from mouse liver.Methods After in vivo collagenase perfusion digestion,various reagents and method,such as Percoll and OptiPrep,were used to extract C57BL/6 mice Kupffer and hepatic stellate cells,and evaluate their purity by flow cytometry and immunofluorescence.Results The two-layer Percoll method to extract Kupffer cells and the two-layer OptiPrep method to extract hepatic stellate cells were feasible,and purity reached>90%.The cell yield was 1～2×107/liver,and the cell survival rate was>90%.After 48 hours of primary cell culture,the number of F4/80-positive Kupffer cells and α-SMA-positive hepatic stellate cells reached>90%.Conclusions The separation and extraction method of Kupffer and hepatic stellate cells from mouse liver are perfect,reliable,cost-effective,and reproducible.
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ObjectiveTo establish a rapid screening method for germplasm materials of Gastrodia elata with high purity， and lay a foundation for pure line breeding and cross breeding. MethodBased on the whole genome sequencing and population resequencing of G. elata， 20 restriction fragment length polymorphism (RFLP) markers were developed by single nucleotide polymorphism (SNP) sites. The polymerase chain reaction (PCR)-RFLP method was used to carry out restriction endonuclease experiments on 20 RFLP markers of 15 G. elata germplasms. According to the number of enzymatic bands at 20 RFLP marker sites, the purity of 15 germplasms was calculated and evaluated. On this basis, genome resequencing technology was used to verify the assessment results. ResultTen germplasm materials with purity greater than 95% were screened out by PCR-RFLP method， 3 of which had 95% purity and 7 had 100% purity. Nine germplasm materials with purity greater than 95% were screened out by genome resequencing methods, and 8 of them were consistent with the results of PCR-RFLP. ConclusionThe PCR-RFLP method established in this study for screening G. elata germplasms with high purity precision of RFLP markers has 80% precision and 89% accuracy. The method is simple， efficient， and significantly less expensive than genome resequencing method, which provides technical support for pure line breeding of G. elata and references for breeding of other Chinese medicinal materials.
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Objective:To investigate the effect of a degradable high-purity magnesium screw in fixing the greater trochanter bone flap of a lateral circumflex femoral artery transverse branch in the treatment of ischemic necrosis of femoral head in young and middle-aged adults.Methods:From February 2017 to February 2019, 12 cases (15 hips) of young and middle-aged patients with avascular necrosis of femoral head were treated in the Department of Orthopaedic of Affiliated Zhongshan Hospital of Dalian University. The age of patients was 30-53 years old. According to Association Research Circulation Osseous (ARCO), 2 hips were graded in stage II b, 4 in ARCO II c, 1 in ARCO III a, 5 in ARCO III b, 2 in ARCO III c and 1 in ARCO IV. The greater trochanter bone flap with a lateral circumferential vascular branch was used to fill the necrotic area, and fixed by a biodegradable high purity magnesium screw in the bone flap transfer. At 3, 6 and 12 months postoperation, the patient came to the hospital outpatient clinic for follow-up, and then were reviewed once a year. Imaging efficacy was evaluated by comparing preoperative and postoperative imaging. The Harris score and Visual Anoalogue Scale (VAS) score were tested at 12 and 24 months after surgery. The Harris score and VAS score before and after surgery were compared by Friedman test, and P<0.05 was considered statistically significant. Results:All 12 patients (15 hips) were entered in the 24-36 months of follow-up. At 12 and 24 months after surgery, Harris score was found at 87 (86, 92) and 90 (87, 92) respertively, which were both higher than that before surgery [59 (52, 74)] with a significant statistical difference ( Z=-3.743, Z=-4.473, P<0.05). However, there was no significant difference in Harris scores between 12 and 24 months after the surgery ( Z=-0.730, P>0.05). At the 12 and 24 months after surgery, VAS score was found at 3 (2, 3) and 2 (1, 3) respertively, which were both lower than that before surgery [6 (5, 6) ] with a significant statistical difference ( Z=-3.560, Z=-4.656, P<0.05). There was no statistical difference in VAS scores between 12 and 24 months after surgery ( Z=-1.095, P>0.05). X-ray and CT scan showed that the bone flaps healed well and the areas of osteonecrosis were repaired. Thirteen femoral heads were in good shape, and 2 femoral heads had further collapse of hips. No patients underwent joint replacement surgery at the time of last follow-up. Conclusion:Fixation of the greater trochanter flap of lateral circumflex femoral artery transverse branch with a degradable high-purity magnesium screw can ensure the healing of the flap at the implantation site and avoid the displacement and shedding of the flap. It is a new therapeutic option to treat the avascular necrosis of femoral head of young and middle-aged people.
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Aim To establish a stable and efficient method for the primary culture of hippocampal neurons from serum-free fetal rats.so as to obtain hippoeampal neurons with higher purity and better vitality.Methods The hippocampal tissues of SI) rat fe¬tus rats on the ( 18 ± 1) day of pregnancy were cultured by Neu- robasal or DMEM/F12 medium and divided into serum-free cul-ture group, fetal bovine serum culture group and 5-fluoro-2'de- oxyuridine culture group.After cells of three groups were cul¬tured for 12 hours, all medium was changed to Neurobasal medi¬um.When the neurons in FUI)R culture group were cultured to 3 days.FLDR was added to inhibit the growth of glial cells.'Hie growing status of hippo cam pal neurons at different culture time points was observed,neuronal activity was detected,cell apopto¬sis was assessed, and the purity of hippocampal neurons was i- dentified.Results Compared with 10% serum culture group, the neurons cultured in serum-free culture group showed higher viability,lower apoptosis rate and higher purity; FUI)R reduced cell viability and increased cell apoptosis.Conclusions 'Hie neurons cultured by serum-free culture have good activity and high purity, instead of adding glial cell inhibitors, which is a fea¬sible and optimized primary culture method for hippocampal neu¬rons.
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Abstract L-Malic acid is the Active Pharmaceutical Ingredient of the latest generation of compound electrolyte injection (STEROFUNDIN ISO, Germany) and plays a very important role in the rescue of critically ill patients. The optical purity of L-malic acid is a Critical Quality Attributes. A new reversed-phase high performance liquid chromatography (RP-HPLC) method for pre-column derivatization of D-malic acid enantiomer impurity in L-malic acid bulk drug was established. The derivatization reaction was carried out using (R)-1-(1-naphthyl)ethylamine ((R)-NEA) as a chiral derivatization reagent. The Kromasil C18 column was used with a detection wavelength of 225 nm, a flow rate of 1.0 mL·min-1, and a column temperature of 30 °C. The mobile phase was acetonitrile-0.01 mol·L-1 potassium dihydrogen phosphate solution (containing 20 mmol·L-1 sodium heptanesulfonate, adjusted to pH 2.80 with phosphoric acid) (at a ratio of 45:55) and the resolution of D-malic acid and L-malic acid derivatization products reached 1.7. The proposed method possesses the advantages of simple operation, mild conditions, stable derivatization products and low cost. Also it gave better separation and was more accurate than previous methods
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Cromatografia Líquida de Alta Pressão/métodos , Malicum Acidum/análise , Cromatografia de Fase Reversa/métodos , Pacientes/classificação , Gestão da Qualidade Total/classificaçãoRESUMO
Introdução: este estudo trata do controle de qualidade do radiofármaco utilizado em estudos de PET-CT para diagnóstico e/ou estadiamento de pacientes acometidos pelo câncer de próstata. Objetivo: avaliar a qualidade do radiofármaco PSMA-11, marcado com uso de gerador de Ge68-Ga68 itinerante. Metodologia: análise do aspecto visual, pH e pureza radioquímica do radiofármaco marcado a cada recebimento do gerador de Ge68-Ga68. Resultado: todas as marcações realizadas se apresentaram límpidas quanto ao aspecto visual, o pH ficou entre 5,0 e 6,0 e a pureza radioquímica apresentou em 92% dos casos valores ≥ 96%. Conclusão: com os devidos controles de qualidade, pode ser uma opção para uso na clínica médica, em serviços que não disponham de condição para adquirir um sistema, por ser importado.
Introduction: this study works with the quality control of the radiopharmaceutical used in PET-CT studies for diagnosis and / or staging of patients affected with prostate cancer. Objective: evaluate the quality of the PSMA-11 marked radiopharmaceutical using a Ge68-Ga68 itinerant generator. Methodology: analysis of the visual aspect, pH and radiochemical purity of the marked radiopharmaceutical on each receiving of the Ge68-Ga68 generator. Results: all performed markings were clear in terms of visual appearance, pH was between 5.0 and 6.0 and radiochemical purity was 92% with value ≥ 96%. Conclusion: with proper quality controls it can be an option for application in the medical clinic, services centers unable to purchase a system due to importation process.
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Neoplasias da Próstata , Controle de Qualidade , Compostos Radiofarmacêuticos , Tomografia por Emissão de Pósitrons combinada à Tomografia ComputadorizadaRESUMO
OBJECTIVE: To study the effect of stains on the purity detection results of human serum albumin by agarose gel electrophoresis, thus to select appropriate stain so that the detection result of agarose gel electrophoresis method can be basically consistent with the method specified in the 2015 edition of Chinese Pharmacopoeia, cellulose acetate membrane electrophoresis method. METHODS: Acid blue, amino black and ponceau were used in agarose gel electrophoresis to detect the purity of 30 batches of human serum albumin samples, and the results were compared with those obtained by cellulose acetate membrane electrophoresis. RESULTS: Impurity bands could not be detected by ponceau stain; the results of amino black staining was significantly lower than that of cellulose acetate membrane electrophoresis. There was no statistical difference between the results of amino black staining and cellulose acetate membrane electrophoresis. The results of 25 batches of samples detected by cellulose acetate membrane electrophoresis were within the 95% confidence interval of the results detected by amino black staining. CONCLUSION: The category of stain has great influence on the detected purity of human serum albumin when using agarose gel electrophoresis. The results of amino black staining is consistent with those of the method recorded in the Chinese Pharmacopoeia in use.
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Antigenic purity is important for quality control of the foot-and-mouth (FMD) whole virus inactivated vaccine. The recommended method for evaluation the antigenic purity of FMD vaccine is to check the serum conversion to non-structural protein (NSP) 3AB antibody after 2 to 3 times inoculation of animals with inactivated vaccine. In this study, we developed a quantitative ELISA to detect the amount of residual 3AB in vaccine antigen, to provide a reference to evaluate the antigenic purity of FMD vaccine. Monoclonal antibody (Mab) of NSP 3A and HRP-conjugated Mab of NSP 3B were used to establish a sandwich ELISA to quantify the NSP 3AB in vaccine antigen of FMD. Purified NSP 3AB expressed in Escherichia coli was serially diluted and detected to draw the standard curve. The detectable limit was determined to be the lowest concentration of standard where the ratio of its OD value to OD blank well was not less than 2.0. Results: The OD value was linearly corelated with the concentration of 3AB protein within the range between 4.7 and 600 ng/mL. The correlation coefficient R² is greater than 0.99, and the lowest detectable limit is 4.7 ng/mL. The amount of 3AB protein in non-purified inactivated virus antigen was detected between 9.3 and 200 ng/mL depending on the 12 different virus strains, whereas the amount of 3AB in purified virus antigen was below the lowest detectable limit. The amount of 3AB in 9 batches of commercial FMD vaccine antigens was between 9.0 and 74 ng/mL, whereas it was below the detectable limit in other 24 batches of commercial vaccine antigens. Conclusion: the sandwich ELISA established in this study is specific and sensitive to detect the content of 3AB protein in vaccine antigen of FMD, which will be a useful method for evaluation of the antigenic purity and quality control of FMD inactivated vaccine.
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Animais , Anticorpos Antivirais , Ensaio de Imunoadsorção Enzimática , Febre Aftosa/prevenção & controle , Vírus da Febre Aftosa , Proteínas não Estruturais Virais/genética , Vacinas ViraisRESUMO
@#Introduction: Rice husk has portrayed great potential in becoming a sustainable biomass source in producing silica, cellulose and carbon materials, which garnered widespread interest among researchers. The objective of the current study is to determine the morphological and compositional changes in rice husk due to the synergistic effects of thermochemical treatment. Methods: Washed and dried rice husk was blended into a fine powder and then subjected to step-wise heat treatment and acid digestion to produce white ash. The intermittent products, as well as the original rice husk and the final ash product, were characterised using analytical instruments to document the morphological and chemical composition changes. Results: This report highlights the production of pure rice husk ash using a step-wise treatment using a combination of thermochemical treatment and carbonisation. The results showed that a partial breakdown of the lignocellulose components was achieved using directed thermal treatment at low temperature. The ionic impurities were leached out in subsequent heated acid treatment. Thereafter, the carbonaceous organic matter was completely converted to carbon during the carbonisation of the sample and the remaining carbon residue was removed during calcination. High purity ash contained agglomerated and nanostructured silica in the dimensions of 20 to 50 nm in the amorphous form. Conclusion: The step-wise treatment allowed systematic removal of each compound while maintaining the amorphous mineral phase of silica and avoiding carbon fixation. Understanding the effect of each treatment offers insight to produce purer silica from rice husk.
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ABSTRACT: The objective of this research was to carry out a survey, through the levels of physical purity, percentage of pure seeds, number of other seeds, and the physiological quality through germination, in the samples of ryegrass seeds analyzed in laboratories accredited by the Ministry of Agriculture, Livestock and Supply in Rio Grande do Sul. Data from 3959 ryegrass samples analyzed from the period 2014 to 2017 were compiled. Quality of the seeds was presented through the percentage of samples within the standards recommended for commercialization, for the variables germination, pure seeds, seeds of cultivated species, wild, noxious, tolerated and noxiously forbidden, in all factors, cultivar, region of origin, category and crop of seed production. Quality of the lots of ryegrass seeds, analyzed by the laboratories of Rio Grande do Sul, obtained in the harvest of 2013 the lowest percentage of lots approved for commercialization, 57.96%, and the harvest of 2014, 2015 and 2016 with 89.60% 91.39% and 91.34%, respectively. In regions where livestock predominates, the percentage of ryegrass seed lots approved for commercialization was lower.
RESUMO: O objetivo desta pesquisa foi realizar um levantamento, através dos níveis de pureza física, em percentagem de sementes puras, número de outras sementes, e qualidade fisiológica através da germinação, nas amostras de sementes de azevém analisadas nos laboratórios credenciados pelo Ministério da Agricultura, Pecuária e Abastecimento do Rio Grande do Sul. Foram compilados os dados de 3959 amostras de azevém, analisadas do período de 2014 a 2017. A qualidade das sementes foi apresentada através da porcentagem de amostras dentro dos padrões recomendados para comercialização, para as variáveis germinação, sementes puras, sementes de espécies cultivadas, silvestres, nocivas toleradas e nocivas proibidas, dentro dos fatores como cultivar, região de procedência, categoria e safra de produção da semente. A qualidade dos lotes de sementes de azevém, analisados pelos laboratórios do Rio Grande do Sul, obteve na safra de 2013 menor porcentagem de lotes aprovados para comercialização, 57,96%, e as safras 2014, 2015 e 2016 com 89,60%, 91,39% e 91,34%, respectivamente. Em regiões em que há predomino da pecuária a porcentagem de lotes de sementes de azevém aprovados para comercialização foi menor.
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Abstract In the present work, we introduce the theoretical development and a new approach to validate a novel method to calibrate the efficiency of a gamma radiation detector for point sources, which we have named the "Efficiency Extrapolation Method". The method consists in the determination of the detector efficiency using a set of monoenergetic gamma sources, which we will refer to as reference efficiencies. From these values, we will extrapolate the detector efficiency to the complete energy range using the first principle physics of gamma radiation detection theory. Therefore the proposed method corresponds to a semi-empirical one. The determination of reference efficiencies must be done experimentally, but in this work, simulations were performed using FLUKA code. The reference energies will be: 59,54 keV, 661,66 keV and 1 274,54 keV associated to the isotopes 241Am, 137Cs and 22Na respectively. The second part of the method, the extrapolation from the reference energies to the gamma range, will be done over the energies emitted by 152Eu and 133Ba. In general, the results are very good. While the obtained results for energies 53,16 keV and greater than 344,3 keV show an excellent agreement, the results obtained for energies in the middle range are only good.
Resumen En el presente trabajo presentamos el desarrollo teórico y un nuevo enfoque para validar un nuevo método para calibrar la eficiencia de un detector de radiación gamma para fuentes puntuales, al cual hemos llamado el método de extrapolación de la eficiencia. El método consiste en la determinación de la eficiencia del detector usando un conjunto de fuentes gamma monoenergéticas, a las cuales llamaremos eficiencias de referencia. Desde estos valores, extrapolaremos la eficiencia del detector al rango completo de energías usando la física de primeros principios de la teoría de detección de radiación gamma. Por lo tanto el método propuesto corresponde a un método semiempírico. La determinación de las eficiencias de referencia debe hacerse experimentalmente, pero en este trabajo, se realizaron simulaciones usando el código FLUKA. Las energías de referencia serán: 59,54 keV, 661,65 keV y 1 274,54 keV asociadas a los isótopos 241 Am, 137Cs y 22Na respectivamente. La segunda parte del método, la extrapolación desde las energías de referencia hacia el rango gamma de las energías, será realizada sobre las energías emitidas por los isótopos 152Eu y 133Ba. En general, los resultados son muy buenos. Mientras que los resultados obtenidos para las energías de 53,16 keV y mayores que 344,3 keV muestran un excelente acuerdo, los resultados obtenidos para las energías del rango intermedio son solo buenas.
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Brazil is the largest world producer, consumer and exporter of forage grass seeds. Urochloa decumbens Stapf. species is the second in importance in the Brazilian market of seeds of tropical forage grasses. Seeds are harvested by the soil sweeping method and, in addition to other impurities, harvested lots can present weed seeds, which makes seeds unfeasible for commercialization. The aim of the present study was to evaluate differences in the physical quality and viability of Urochloa decumbens cv. Basilisk seeds produced in different production fields. Fifteen U. decumbens seed lots from the State of São Paulo (1 lot in the municipality of Cássia dos Coqueiros and 3 lots in the municipality of Santo Antônio da Alegria), Minas Gerais (2 lots in the municipality of Tupaciguara, 2 lots in the municipality of Unaí, 2 lots in the municipality of Chapada Gaúcha and 3 lots in the municipality of Monte Santo de Minas), Goiás (1 lot in the municipality of Jataí) and Mato Grosso (1 lot in the municipality of Primavera do Leste) were evaluated by means of the following parameters: water content, viability by tetrazolium test, purity, determination of other seeds by number and weight of one thousand seeds. A completely randomized design was used, and when significant, the means of treatments were compared by the Scott Knott test at 5% probability. The fields of the different regions produce U. decumbens seeds with high variability in physical quality. U. decumbens seeds with the highest physical quality and viability were produced in Cassia dos Coqueiros - SP.
O Brasil é o maior produtor, consumidor e exportador de sementes de forrageiras no mundo. A espécie Urochloa decumbens Stapf. é a segunda em importância no mercado brasileiro de sementes de gramíneas forrageiras tropicais. A colheita das sementes ocorre pelo método de varredura do solo e, além de outras impurezas, podem apresentar sementes de plantas daninhas que podem inviabilizar a comercialização de lotes de sementes. A presente pesquisa teve como objetivo avaliar diferenças na qualidade física e viabilidade de sementes de Urochloa decumbens cv. Basilisk produzidas em diferentes campos de produção. Foram avaliados 15 lotes de sementes de U. decumbens, procedentes dos Estados de São Paulo (1 lote do município de Cássia dos Coqueiros e 3 lotes do município de Santo Antônio da Alegria), Minas Gerais (2 lotes do município de Tupaciguara, 2 lotes do município de Unaí, 2 lotes do município de Chapada Gaúcha e 3 lotes do município de Monte Santo de Minas), Goiás (1 lote do município de Jataí) e Mato Grosso (1 lote do município de Primavera do Leste); por meio dos seguintes parâmetros: teor de água, viabilidade pelo teste de tetrazólio, pureza, determinação de outras sementes por número e massa de mil sementes. Adotou-se o delineamento inteiramente casualizado e as médias dos tratamentos foram comparadas pelo teste de Scott Knott, a 5% de probabilidade. Os campos das diferentes regiões produzem sementes de U. decumbens com alta variabilidade na qualidade física. As sementes de U. decumbens com maior qualidade física e viabilidade foram produzidas em Cassia dos coqueiros SP.
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Sementes , Brachiaria , Plantas Daninhas , PoaceaeRESUMO
BACKGROUND: Microsatellite instability (MSI) analysis is becoming increasingly important in many types of tumor including colorectal cancer (CRC). The commonly used MSI tests are either time-consuming or labor-intensive. A fully automated MSI test, the Idylla MSI assay, has recently been introduced. However, its diagnostic performance has not been extensively validated in clinical CRC samples.METHODS: We evaluated 133 samples whose MSI status had been rigorously validated by standard polymerase chain reaction (PCR), clinical next-generation sequencing (NGS) cancer panel test, or both. We evaluated the diagnostic performance of the Idylla MSI assay in terms of sensitivity, specificity, and positive and negative predictive values, as well as various sample requirements, such as minimum tumor purity and the quality of paraffin blocks.RESULTS: Compared with the gold standard results confirmed through both PCR MSI test and NGS, the Idylla MSI assay showed 99.05% accuracy (104/105), 100% sensitivity (11/11), 98.94% specificity (93/94), 91.67% positive predictive value (11/12), and 100% negative predictive value (93/93). In addition, the Idylla MSI assay did not require macro-dissection in most samples and reliably detected MSI-high in samples with approximately 10% tumor purity. The total turnaround time was about 150 minutes and the hands-on time was less than 2 minutes.CONCLUSIONS: The Idylla MSI assay shows good diagnostic performance that is sufficient for its implementation in the clinic to determine the MSI status of at least the CRC samples. In addition, the fully automated procedure requires only a few slices of formalin-fixed paraffin-embedded tissue and might greatly save time and labor.
Assuntos
Neoplasias Colorretais , Instabilidade de Microssatélites , Repetições de Microssatélites , Parafina , Reação em Cadeia da Polimerase , Sensibilidade e EspecificidadeRESUMO
Objective To compare the in vivo degradation rates of two different kinds of high purity magnesium bone screws by animal experiments, so as to make some suggestions on structural design of high purity magnesium bone screws. Methods High purity magnesium bone screws with threads and without threads were implanted into femoral condyles of New Zealand rabbits separately. Twenty-four rabbits were randomly divided into 3 groups. They were euthanized at 8, 12 and 16 weeks after operation, respectively. The in vivo degradation rates of bone screws with two different shapes were compared through micro-CT scanning and Skyscan CT-analyser software, and the stress changes during the progress of bone screw degradation were analyzed. Results The initial surface area of threaded screws ［(31.70±0.06) mm2］ was significantly greater than that of the non-threaded ones ［(29.56±0.22) mm2］. After 8, 12 and 16 weeks, the volume loss ratios of the threaded screws were (26.01±3.44)%, (33.35±5.05)%, (36.84±6.99)%, respectively, and the volume loss ratios of the non-threaded screws were (22.53±4.78)%, (31.12±6.59)%, (43.22±9.31)%, respectively. At the same time point, there were no significant differences in the volume loss ratio between two kinds of screws. The relationship between the volume reduction and the implantation time was linear for non-threaded screws and gradually decreasing for threaded screws. Conclusions Under the low-bearing condition, different structural design for high purity magnesium screws has no obvious effect on their degradation rate in vivo.