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1.
Clin Chem Lab Med ; 59(10): 1728-1734, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34225391

RESUMO

OBJECTIVES: The US Centers for Medicare & Medicaid Services proposed in 2019 that glycated hemoglobin A1c (HbA1c) be a CLIA'88 regulated analyte. People who commented expressed concerns that the proposed acceptance limit (AL, HbA1c in NGSP unit) ±10% for proficiency testing (PT) would be unable to maintain already improved analytical performance and guarantee the clinical utility of HbA1c testing. Assessing impact of various ALs on PT performance is needed to provide scientific evidence for adopting an appropriate AL. METHODS: Ten patient EDTA-whole blood specimens were distributed to 318 and 336 laboratories in the 2018 and 2019 PT events organized by Shanghai Center for Clinical Laboratory (SCCL). HbA1c concentrations were measured by participants using various methodologies commonly used in the USA and China. Targets were determined using secondary reference measurement procedures (SRM) at SCCL. "Failed Results" were those outside the SRM-defined target ± AL (5% through 10%). Laboratories with Failed Results ≥2 out of five samples per PT event obtained Event Unsatisfactory Status. RESULTS: HbA1c target values ranged 33.3 mmol/mol (5.2 NGSP%) -102.2 mmol/mol (11.5 NGSP%) for 2018 event, and 33.3 mmol/mol (5.2 NGSP%) -84.7 mmol/mol (9.9 NGSP%) for 2019 event. Overall Laboratory Event Unsatisfactory Rates were 11.3-12.2%, 4.8-5.3%, 0.9-3.1%, 0.6-2.2%, 0.6-1.4% and 0.6-1.4%, at AL of ±5, ±6, ±7, ±8, ±9 and ±10%, respectively. CONCLUSIONS: The AL (in NGSP unit) of ±6% or ±7% for PT evaluation of HbA1c results would be appropriate, with satisfactory event scores for about 95% of participant laboratories in a PT event.


Assuntos
Laboratórios Clínicos , Medicare , Idoso , China , Hemoglobinas Glicadas/análise , Hemoglobina Falciforme , Humanos , Estados Unidos
2.
Addict Biol ; 25(2): e12687, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-30421575

RESUMO

Addictions, both substance and behavioral, have been conceptualized as involving similar biopsychosocial processes with different opportunistic expressions. A maladaptive stress response in combination with craving or urges to engage in the addictive behavior may be among the underlying factors common to behavioral and substance addictions. The current study compared the neuroendocrine (cortisol) and subjective responses to stress of gamblers and smokers to healthy controls. We assessed if participants responded differently to smoking or gambling cues before and after a psychosocial stressor. To this end, the subjective urges/cravings of all participants were measured in response to smoking or gambling cues versus neutral cues, once under normal conditions and again after exposure to a stressor. Salivary cortisol was measured prior to, immediately following, and 10 minutes after conclusion of the stressor. Smokers and gamblers showed a similar blunted cortisol response to the acute stressor that differed from the control group's response. Following a stressor, subjective craving in smokers increased whereas gamblers' urges decreased. In smokers, a blunted cortisol and subjective stress response were related to increased urges. In contrast, for gamblers, changes in cortisol levels were unrelated to urges, and higher subjective stress was associated with decreased urges. In conclusion, individuals with a substance and a behavioral addiction share common patterns of reactivity to stress. However, while the stressor enhanced cue-related craving in smokers, it generally had the opposite effect on gamblers. Further research is necessary to elucidate the complicated patterns of similarities and differences that underlie substance and behavioral addictions.


Assuntos
Sinais (Psicologia) , Jogo de Azar/metabolismo , Jogo de Azar/fisiopatologia , Estresse Psicológico/metabolismo , Tabagismo/metabolismo , Tabagismo/fisiopatologia , Adulto , Feminino , Jogo de Azar/psicologia , Humanos , Hidrocortisona/metabolismo , Masculino , Saliva/metabolismo , Índice de Gravidade de Doença , Fumantes , Estresse Psicológico/fisiopatologia , Estresse Psicológico/psicologia , Tabagismo/psicologia
3.
Mol Biol Rep ; 46(3): 3083-3092, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30859446

RESUMO

Two novel miRNAs were selected from a pre-constructed RNA library of Populus szechuanica infected with the foliar rust fungus Melampsora larici-populina in order to detect the genes regulated as targets of the miRNAs novel_mir_11 and novel_mir_357. The novel miRNAs were identified from P. szechuanica using stem-loop methods and their precursors were able to fold into a complete stem loop structure. The predicted target genes of the novel miRNAs were verified with RNA ligase-mediated 5' rapid amplification of cDNA ends (RLM-5'RACE). The full-length sequences of target genes, RPM1 and RPS2/5, in P. szechuanica were obtained through rapid amplification of cDNA ends (RACE) and officially named PsRPM1 and PsRPS2/5. These genes contain nucleotide binding site-leucine-rich repeats (NBS-LRR) domains typical of resistance genes. The expression levels of miRNAs and their target genes in different periods post infection were analysed with quantitative real-time PCR (qRT-PCR). After infection with the foliar rust fungus, the expression levels of the novel miRNAs and their target genes were dynamic. Both novel_mir_11 and novel_mir_357 negatively regulated the expression of their target genes. In this study, the regulatory effects of two novel miRNAs through their target genes were characterized to provide further mechanistic information regarding the interaction between Populus and a foliar rust fungus. Results of this study improve our understanding of the defence response mechanisms of Populus and will stimulate future work to characterize strategies to prevent and control Populus diseases.


Assuntos
Basidiomycota , MicroRNAs/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Populus/genética , Populus/microbiologia , RNA Mensageiro/genética , Sítios de Ligação , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno/genética , MicroRNAs/química , Conformação de Ácido Nucleico , Filogenia , Interferência de RNA , RNA Mensageiro/química , Reação em Cadeia da Polimerase em Tempo Real
4.
Anal Bioanal Chem ; 411(2): 395-402, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30456606

RESUMO

Immunoassays for measuring 17-hydroxyprogesterone (17-OHP) produce high rates of false positives that impact the identification of congenital adrenal hyperplasia (CAH) in neonates. A confirmatory test with high analytical specificity employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) methodology is needed in newborn screening for CAH. 17-OHP and cortisol were extracted from dried blood spot (DBS) samples, resolved on a C18 column, and measured using tandem mass spectrometry. The results were compared with those determined using the AutoDELFIA immunoassay. The LC-MS/MS method had a limit of quantitation of 10.0 and 5.0 ng/mL for 17-OHP and cortisol, respectively. The method characteristics showed coefficient variation (%CV) ≤ 11.9% for both 17-OHP and cortisol, recoveries ranging from 83.1 to 101.5% for 17-OHP and from 95.1 to 102.8% for cortisol, and linearity with R2 = 0.9994 for 17-OHP and R2 = 0.9996 for cortisol, clinical sensitivity of 100.0% and a specificity of 96.4% as obtained by receiver operating characteristic analysis on 45 patient samples when 17-OHP > 39.1 ng/mL was selected as the cutoff value. Comparison between the LC-MS/MS and the AutoDELFIA immunoassay methods revealed a poor correlation for patient DBS samples (R2 = 0.6784); however, an excellent correlation was obtained for QC and proficiency test (PT) DBS samples (R2 = 0.9797). The LC-MS/MS method produced reliable results for 17-OHP and cortisol for the diagnosis of CAH. The AutoDELFIA immunoassay appears to be subject to matrix effects in the analysis for 17-OHP in DBS patient samples. The DBS samples of non-patient origin may not be suitable for assessing analytical accuracy of immunoassays.


Assuntos
17-alfa-Hidroxiprogesterona/sangue , Cromatografia Líquida , Imunoensaio/métodos , Espectrometria de Massas em Tandem , 17-alfa-Hidroxiprogesterona/química , Humanos , Recém-Nascido , Estrutura Molecular , Sensibilidade e Especificidade , Testes Sorológicos
5.
Anal Bioanal Chem ; 411(6): 1203-1210, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30612174

RESUMO

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) for measurements of steroids in human saliva has garnered increased interest in the area of clinical psychoneuroendocrinological research. However, performance characteristics of LC-MS/MS methods for the analysis of steroids in saliva are limited. Human saliva samples were collected via passive drool. Cortisol and dehydroepiandrosterone sulfate (DHEA-S) in the samples were extracted together, resolved on a C18-A column, and analyzed using tandem mass spectrometry. The LC-MS/MS method had limits of quantitation of 0.03 and 0.06 ng/mL for DHEA-S and cortisol, respectively. Method evaluations showed coefficient variation (%CV) of inter-assay ranging 4.6-17.9% for DHEA-S and cortisol, recoveries of 102.4-109.5% for DHEA-S and 94.6-98.3% for cortisol, and assay linearity with R2 = 0.9964 for DHEA-S (1.0-25.0 ng/mL) and R2 = 0.997 (1.0-25.0 ng/mL) for cortisol. No cross contamination among samples was observed. Human saliva showed 20% and 18% ion enhancement effect for DHEA-S and cortisol assay, respectively. No interference by ten common steroids was detected. Regression analysis of method comparisons with laboratory-developed test (LDT) method revealed R2 = 0.9688 (LC-MS/MS = 0.9665 LDT-LC-MS/MS - 0.7355) for cortisol, and R2 = 0.9039 (LC-MS/MS = 1.0173 LDT-LC-MS/MS + 3.6797) for DHEA-S. Reference ranges for young adults were determined to be 0.3-5.9 ng/mL for females and 0.1-5.6 ng/mL for males for salivary cortisol, and 0.6-7.4 ng/mL for females and 0.6-10.1 ng/mL for males for salivary DHEA-S. An LC-MS/MS method for quantifying cortisol and DHEA-S in human saliva was developed and validated for clinical and psychoneuroendocrinological research that require noninvasive means of measuring these hormones.


Assuntos
Sulfato de Desidroepiandrosterona/análise , Hidrocortisona/análise , Saliva/química , Espectrometria de Massas em Tandem/métodos , Adolescente , Adulto , Cromatografia Líquida/métodos , Feminino , Humanos , Limite de Detecção , Masculino , Valores de Referência , Adulto Jovem
6.
Anal Bioanal Chem ; 410(24): 6257-6267, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30006726

RESUMO

A candidate reference measurement procedure (RMP) for measurement of unconjugated estriol in human serum has been developed and validated. The proposed method is highly reliable and uses isotope dilution coupled with liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) and requires no derivatization. An appropriate amount of serum was accurately weighed and spiked with an isotopically labeled internal standard. Unconjugated estriol and its internal standard were extracted from serum matrix using liquid-liquid extraction prior to reversed-phase LC-MS/MS. Calibrator bracketing was used to give higher specificity and accuracy for assigning serum level. The accuracy of the candidate RMP was validated by split-sample comparison to established RMPs. The lowest limit of detection (LLoD) and lowest limit of quantification (LLoQ) for developed RMP was estimated to be 0.14 nmol/L and 0.35 nmol/L, respectively. Both intra- and inter-assay imprecisions were ≤2.19% at 1.39, 17.34 and 69.35 nmol/L, respectively. Recoveries were 98.54% to 100.34% and linear response ranged from 0.35 to 173.38 nmol/L. No interference was observed. Biases were 5.6% and 2.8% against the targets of RELA2015A (3.87 nmol/L) and RELA2015B (40.62 nmol/L), respectively. Moreover, the candidate RMP was successfully applied to measure level of unconjugated estriol in serum samples of pregnant women (n = 3) and compared with two immunoassays in clinical laboratory. Our developed method is simple, accurate, and can be used as a candidate RMP to determine total unconjugated estriol level in human serum. Further improvement of certain immunoassays in accuracy and precision is needed. Graphical abstract Selected ion chromatograms by LC-MS/MS using a C18 column for uE3 from a serum sample.


Assuntos
Cromatografia Líquida/métodos , Estriol/sangue , Imunoensaio/métodos , Espectrometria de Massas em Tandem/métodos , Calibragem , Estriol/normas , Feminino , Humanos , Limite de Detecção , Gravidez , Padrões de Referência , Reprodutibilidade dos Testes , Incerteza
7.
Theor Appl Genet ; 130(11): 2375-2393, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28831522

RESUMO

KEY MESSAGE: A novel genetic linkage map was constructed using SSR markers and stable QTLs were identified for six drought tolerance related-traits using single-environment analysis under irrigation and drought treatments. Mungbean (Vigna radiata L.) is one of the most important leguminous food crops. However, mungbean production is seriously constrained by drought. Isolation of drought-responsive genetic elements and marker-assisted selection breeding will benefit from the detection of quantitative trait locus (QTLs) for traits related to drought tolerance. In this study, we developed a full-coverage genetic linkage map based on simple sequence repeat (SSR) markers using a recombinant inbred line (RIL) population derived from an intra-specific cross between two drought-resistant varieties. This novel map was anchored with 313 markers. The total map length was 1010.18 cM across 11 linkage groups, covering the entire genome of mungbean with a saturation of one marker every 3.23 cM. We subsequently detected 58 QTLs for plant height (PH), maximum leaf area (MLA), biomass (BM), relative water content, days to first flowering, and seed yield (Yield) and 5 for the drought tolerance index of 3 traits in irrigated and drought environments at 2 locations. Thirty-eight of these QTLs were consistently detected two or more times at similar linkage positions. Notably, qPH5A and qMLA2A were consistently identified in marker intervals from GMES5773 to MUS128 in LG05 and from Mchr11-34 to the HAAS_VR_1812 region in LG02 in four environments, contributing 6.40-20.06% and 6.97-7.94% of the observed phenotypic variation, respectively. None of these QTLs shared loci with previously identified drought-related loci from mungbean. The results of these analyses might facilitate the isolation of drought-related genes and help to clarify the mechanism of drought tolerance in mungbean.


Assuntos
Mapeamento Cromossômico , Secas , Ligação Genética , Locos de Características Quantitativas , Vigna/genética , Meio Ambiente , Marcadores Genéticos , Repetições de Microssatélites , Fenótipo , Folhas de Planta/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Vigna/fisiologia
8.
Mycologia ; 108(4): 668-81, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27055569

RESUMO

Canker disease of prickly ash (Zanthoxylum bungeanum) has caused a decline in the production of this economically important spice in northern China in the past 25 y. To identify the etiological agent, 38 fungal isolates were recovered from symptomatic tissues from trees in five provinces in China. These isolates were identified by conducting BLASTN queries of NCBI GenBank and phylogenetic analyses of DNA sequence data from the nuclear ribosomal internal transcribed spacer region (ITS rDNA), a portion of the translation elongation factor 1-α (TEF1) gene, and genes encoding RNA polymerase II largest (RPB1) and second largest (RPB2) subunits. Results of these analyses suggested that 30/38 isolates belonged to two novel fusaria most closely related to the Florida torreya (Torreya taxifolia Arn.) pathogen, Fusarium torreyae in Florida and Georgia. These three canker-inducing tree pathogens form a novel clade within Fusarium here designated the F. torreyae species complex (FTOSC). BLASTN queries of GenBank also revealed that 5/38 isolates recovered from cankers represented an undescribed phylogenetic species within the F. solani species complex (FSSC) designated FSSC 6. Stem inoculations of three fusaria on Z. bungeanum resulted in consistent canker symptoms from which these three fusaria were recovered. The two novel fusaria, however, induced significantly larger lesions than FSSC 6. Herein, the two novel prickly ash pathogens are formally described as F. zanthoxyli and F. continuum.


Assuntos
Fusarium/classificação , Fusarium/isolamento & purificação , Doenças das Plantas/microbiologia , Zanthoxylum/microbiologia , China , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA de Plantas/química , DNA de Plantas/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Fusarium/genética , Dados de Sequência Molecular , Fator 1 de Elongação de Peptídeos/genética , Filogenia , RNA Polimerase II/genética , Análise de Sequência de DNA
9.
Int J Mol Sci ; 17(7)2016 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-27376270

RESUMO

In this report, the effects of two oligochitosans, i.e., oligochitosan A (OCHA) and oligochitosan B (OCHB), on control of dry rot of Zanthoxylum bungeanum (Z. bungeanum) caused by Fusarium sambucinum (F. sambucinum) were evaluated. First, both oligochitosans show desirable ability to decrease the infection of F. sambucinum. Second, the oligochitosans strongly inhibit the radial colony and submerged biomass growth of F. sambucinum. Lastly, these oligochitosans are capable of increasing the activities of phenylalanine ammonia lyase (PAL), polyphenoloxidase (PPO) and peroxidase (POD) significantly, as well as enhancing the content of total phenolics in Z. bungeanum stems. These findings indicate that the protective effects of OCHA and OCHB on Z. bungeanum stems against dry rot may be associated with the direct fungitoxic function against pathogen and the elicitation of biochemical defensive responses in Z. bungeanum stems. The outcome of this report suggests that oligochitosans may serve as a promising natural fungicide to substitute, at least partially, for synthetic fungicides in the disease management of Z. bungeanum.


Assuntos
Quitina/análogos & derivados , Zanthoxylum/química , Catecol Oxidase/metabolismo , Quitina/química , Quitina/farmacologia , Quitosana , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Oligossacarídeos , Peroxidase/metabolismo , Fenóis/química , Fenóis/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Caules de Planta/química , Caules de Planta/enzimologia , Caules de Planta/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier , Zanthoxylum/enzimologia , Zanthoxylum/metabolismo
10.
Int J Mol Sci ; 17(12)2016 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-27973408

RESUMO

Oligosaccharide elicitors from pathogens have been shown to play major roles in host plant defense responses involving plant-pathogen chemoperception and interaction. In the present study, chitosan and oligochitosan were prepared from pathogen Fusarium sambucinum, and their effects on infection of Zanthoxylum bungeanum stems were investigated. Results showed that oligochitosan inhibited the infection of the pathogen, and that the oligochitosan fraction with a degree of polymerization (DP) between 5 and 6 showed the optimal effect. Oligochitosan DP5 was purified from fraction DP5-6 and was structurally characterized using electrospray ionization mass spectrometry, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy. Oligochitosan DP5 showed significant inhibition against the infection of the pathogenic fungi on host plant stems. An investigation of the mechanism underlying this effect showed that oligochitosan DP5 increased the activities of defensive enzymes and accumulation of phenolics in host Z. bungeanum. These results suggest that oligochitosan from pathogenic fungi can mediate the infection of host plants with a pathogen by acting as an elicitor that triggers the defense system of a plant. This information will be valuable for further exploration of the interactions between the pathogen F. sambucinum and host plant Z. bungeanum.


Assuntos
Quitina/análogos & derivados , Fusarium/química , Zanthoxylum/imunologia , Zanthoxylum/microbiologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Quitina/química , Quitina/isolamento & purificação , Quitina/farmacologia , Quitosana/isolamento & purificação , Quitosana/farmacologia , Oligossacarídeos , Fenóis/metabolismo , Doenças das Plantas/microbiologia , Caules de Planta/efeitos dos fármacos , Caules de Planta/microbiologia , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Zanthoxylum/efeitos dos fármacos , Zanthoxylum/enzimologia
11.
BMC Genomics ; 16: 696, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26370267

RESUMO

BACKGROUND: MicroRNAs (miRNAs) are small non-coding RNAs that regulate the gene expression of target mRNAs involved in plant growth, development, and abiotic stress and pathogen responses. Previous studies have reported miRNAs in Populus that respond to abiotic stresses, such as cold, heat, drought, flooding, high salt and mechanical stress. However, little is known about the regulatory roles of these molecules in the Populus response to the stress of foliar rust fungal infection. Here, we identified the miRNA profiles of Populus after inoculation with Melampsora larici-populina using high-throughput sequencing and bioinformatics analysis. Quantitative real-time PCR (qRT-PCR) was used to validate the expression levels of 10 miRNAs. RESULTS: A total of 90 known miRNAs belonging to 42 families and 378 novel miRNAs were identified from three small-RNA libraries of Populus szechuanica infected with M. larici-populina isolates Sb052 and Th053 and a control. Comparative analysis revealed that the expression of 38 known miRNAs and 92 novel miRNAs in P. szechuanica after infection with different rust fungus isolates showed significant differences, and more miRNAs were suppressed during rust infection. Among the differentially expressed miRNAs, 7 known and 20 novel miRNAs were relevant to the rust fungus infection, and according to KEGG (Kyoto Encyclopaedia of Genes and Genomes) pathway analysis, these miRNAs primarily regulate genes encoding disease-resistance proteins, serine/threonine protein kinases, transcription factors, and related proteins. QRT-PCR analysis indicated that most miRNAs were up-regulated in the Sb052 library and down-regulated in the Th053 library at 48 h post-inoculation (hpi). CONCLUSIONS: These results demonstrate that the expression of miRNAs was altered in poplar under stress associated with M. larici-populina infection, and different temporal dynamics were observed in incompatible and compatible libraries. These findings suggest important roles for miRNA regulation in Populus upon infection with foliar rust fungus.


Assuntos
Basidiomycota , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Populus/genética , Populus/microbiologia , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno , Família Multigênica , Populus/metabolismo , Interferência de RNA , RNA Mensageiro/genética , Transdução de Sinais , Estresse Fisiológico/genética
12.
Clin Chem ; 60(1): 260-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24255078

RESUMO

BACKGROUND: Unconjugated estriol (uE3) is routinely analyzed in clinical laboratories as risk assessment for Down syndrome. Immunoassays of various types are the most commonly used methods. The accuracies of RIAs and ELISAs for uE3 have been questioned, and to date there have been no independent studies investigating the accuracy of the relatively new chemiluminescent immunoassays. We developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for uE3 measurements in serum. METHODS: Serum samples from patients in the second trimester of pregnancy were used, and uE3 concentrations were measured by LC-MS/MS and the Beckman Coulter Access® 2 and Siemens IMMULITE 2000 automatic chemiluminescent immunoassay analyzers. RESULTS: The LC-MS/MS method was validated and showed limit of detection 0.05 ng/mL; limit of quantification 0.2 ng/mL; linearity of response to 32 ng/mL; total imprecision of 16.2%, 10.4%, and 8.2% for uE3 at 1.10, 4.18, and 8.32 ng/mL, respectively; and analytical recoveries of 95.9%-104.2%. ANOVA of the correlation for LC-MS/MS results vs chemiluminescent immunoassays results showed R(2) = 0.9678 (Access 2 = 0.9305 LC-MS/MS + 0.2177, Sy|x = 0.1786, P < 0.0001), and R(2) = 0.9663 (IMMULITE 2000 = 0.8849 LC-MS/MS - 0.0403, Sy|x = 0.1738, P < 0.0001). Bland-Altman plots of uE3 results revealed concentration-dependent immunoassay biases. Mock risk analysis for Down syndrome showed no apparent difference in the risk assessment outcomes if the adjusted method-specific multiples of the median were used, and the assay imprecision was <10% CV. CONCLUSIONS: Standardization of immunoassay methods for uE3 analysis is needed to improve the accuracy of the measurements.


Assuntos
Cromatografia Líquida , Testes de Química Clínica/normas , Estriol/sangue , Imunoensaio/normas , Medições Luminescentes/normas , Espectrometria de Massas em Tandem , Síndrome de Down/diagnóstico , Estriol/química , Feminino , Humanos , Masculino , Gravidez , Padrões de Referência , Reprodutibilidade dos Testes
13.
Clin Biochem ; 124: 110700, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043696

RESUMO

OBJECTIVES: Accuracy of estradiol measurements is important but conventional proficiency testing (PT) cannot assess accuracy when possibly non-commutable samples are used and method peer-group means are the targets. Accuracy-based assessment of estradiol measurements is needed. DESIGN AND METHODS: Five serum samples were prepared from single donors, frozen, and distributed overnight to 76 New York State Department of Health (NYSDOH)-certified laboratories. Participants analyzed samples for estradiol. The biases of group means were assessed against the Centers for Disease Control and Prevention (CDC)-defined targets, evaluated using the Hormone Standardization Program (HoSt) E2 performance criterion of ±12.5 %. Each laboratory's performance was evaluated using total allowable error (acceptance limits) of target ±25 % or ±15 pg/mL (55 pmol/L) (whichever was greater, NYSDOH), target ±30 % (Clinical Laboratory Improvement Amendments [CLIA]), and target ±26 % (minimal limit based on biological variation [BV]). RESULTS: The biases (range) were 34 % (-17 % to 175 %), 40 % (-33 % to 386 %), 16 % (-45 % to 193 %), 5 % (-27 % to 117 %), and -4% (-31 % to 21 %), for samples at estradiol of 24.1, 28.4, 61.7, 94.1, and 127 pg/mL, or 89, 104, 227, 345, and 466 pmol/L, respectively. Large positive method/analytical systematic biases were revealed for 9 commonly used method/analytical systems in the United States at low estradiol concentrations. Of the 9 analytical systems, 0, 0, 3, 7 and 6 met the HoSt criterion for the samples with estradiol at the five respective concentrations. PT evaluation showed that 59 %, 69 % and 87 % of laboratories would receive a PT event passing (satisfactory) score when the CDC-defined target and a criterion of NYSDOH, CLIA or BV was used, respectively. However, >95 % laboratories would obtain PT passing score if method peer-group means were used as targets regardless of the criterion used. CONCLUSIONS: Improvement in accuracy of estradiol measurements is needed, particularly at low estradiol concentrations. Accuracy-based PT provides unambiguous information about the accuracy of methods/analytical systems.


Assuntos
Serviços de Laboratório Clínico , Ensaio de Proficiência Laboratorial , Humanos , Estados Unidos , Laboratórios , Padrões de Referência , Laboratórios Clínicos
14.
Gene ; 920: 148506, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38670390

RESUMO

The acquisition of nutrients from host plants by phytopathogenic fungi is critically important for their invasion success. Melampsora larici-populina, an obligate biotrophic pathogenic fungus, causes the poplar leaf rust disease and can severely damage host poplar plants. Previously, we found that oligopeptide transporters (OPTs) have undergone a convergent expansion, which might reflect adaptation to a phytoparasitic lifestyle. Here, we used various methods to evaluate this hypothesis, including conserved motif identification, positive selection signal mining, expression pattern clustering analysis, and neutral selection tests. The motif composition of the five clades in the OPT family differed, and positive selection was observed during clade differentiation. This suggests that OPTs in these five clades may be functionally differentiated, which would increase the range of transported substrates and promote the absorption of more types of nitrogen compounds from the hosts. According to clustering analysis of gene expression patterns, the expression of most genes from the two expanded clades (clade 2 and 4) was up-regulated during the infection of poplar trees, indicating that the expansion of OPTs likely occurred to promote the uptake of oligopeptides from host poplar plants. The MellpOPT4g gene was determined to be under significant balancing selection based on the neutral selection tests, suggesting that it plays a role in the pathogenic process. In conclusion, these three observations provide preliminary evidence supporting our hypothesis, as they indicate that the expansion of OPTs in M. larici-populina has aided the ability of this pathogen to acquire nutrients from host plants.


Assuntos
Basidiomycota , Proteínas Fúngicas , Oligopeptídeos , Doenças das Plantas , Populus , Populus/genética , Populus/parasitologia , Populus/microbiologia , Oligopeptídeos/metabolismo , Oligopeptídeos/genética , Basidiomycota/genética , Basidiomycota/patogenicidade , Basidiomycota/metabolismo , Doenças das Plantas/parasitologia , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Filogenia , Adaptação Fisiológica/genética , Regulação Fúngica da Expressão Gênica , Seleção Genética
15.
J Funct Biomater ; 15(6)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38921526

RESUMO

Silver nanoparticles (AgNPs) are known for their antibacterial properties and their ability to promote wound healing. By incorporating silver nanoparticles into medical gauze, the resulting composite material shows promise as an advanced wound dressing. However, clinical applications are hindered by challenges related to the stability of silver nanoparticle loading on the gauze as nanoparticle leaching can compromise antibacterial efficacy. In this study, silver nanoparticles were immobilized onto polydopamine (PDA) submicron particles, which were then used to modify medical gauze. Energy dispersive spectroscopy (EDS) was employed to analyze the elemental distribution on the modified gauze, confirming successful surface modification. The antibacterial properties of the modified gauze were assessed using a laser scanning confocal microscope (CLSM). The results demonstrated a significant reduction in the adhesion rates of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by 99.1% and 63%, respectively, on the PDA-Ag-modified gauze. Optical density (OD) measurements at 590 nm indicated that the modified gauze effectively inhibited biofilm formation, underscoring its potent antimicrobial capabilities. Further antibacterial efficacy was evaluated by diluting and plating co-cultured bacterial solutions with the modified dressing, followed by 24 h incubation and colony counting. The gauze exhibited an antibacterial efficiency of 99.99% against E. coli and 99.8% against S. aureus. Additionally, cell compatibility tests, involving the co-culture of PDA-Ag composites with human cells, demonstrated excellent biocompatibility. These findings suggest that PDA-Ag-modified medical gauze holds significant potential for the treatment of infected wounds, offering a promising solution to improve wound care through enhanced antimicrobial activity and biocompatibility.

16.
Biomimetics (Basel) ; 8(6)2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37887633

RESUMO

The adhesion of marine-fouling organisms to ships significantly increases the hull surface resistance and expedites hull material corrosion. This review delves into the marine biofouling mechanism on marine material surfaces, analyzing the fouling organism adhesion process on hull surfaces and common desorption methods. It highlights the crucial role played by surface energy in antifouling and drag reduction on hulls. The paper primarily concentrates on low-surface-energy antifouling coatings, such as organic silicon and organic fluorine, for ship hull antifouling and drag reduction. Furthermore, it explores the antifouling mechanisms of silicon-based and fluorine-based low-surface-energy antifouling coatings, elucidating their respective advantages and limitations in real-world applications. This review also investigates the antifouling effectiveness of bionic microstructures based on the self-cleaning abilities of natural organisms. It provides a thorough analysis of antifouling and drag reduction theories and preparation methods linked to marine organism surface microstructures, while also clarifying the relationship between microstructure surface antifouling and surface hydrophobicity. Furthermore, it reviews the impact of antibacterial agents, especially antibacterial peptides, on fouling organisms' adhesion to substrate surfaces and compares the differing effects of surface structure and substances on ship surface antifouling. The paper outlines the potential applications and future directions for low-surface-energy antifouling coating technology.

17.
Braz J Otorhinolaryngol ; 89(4): 101278, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37331234

RESUMO

OBJECTIVE: To investigate the effect of peroxynitrite on the cultured cochlear hair cells of C57BL/6 P3 mice in vitro as well as the role of Wnt3a, as an activator of the canonical Wnt signaling pathway, underlying the action of such an oxidative stress. METHODS: The in vitro primary cultured cochlear hair cells were subjected to l00 µM peroxynitrite and l00 µM peroxynitrite +25 ng/mL Wnt3a for 24 h, the cell survival and morphological changes were examined by immunofluorescence and transmission electron microscopy. RESULTS: The number of surviving hair cells was significantly reduced in the 100 µM peroxynitrite group, while it was significantly higher in the Wnt3a + peroxynitrite treated group compared with the peroxynitrite treated group. The transmission electron microscopy showed that exposure to peroxynitrite induced a dramatic decrease in the number of mitochondria and severely disrupted mitochondrial ultrastructure, while Wnt3a clearly diminished the disruption of mitochondrial structure and preserved a higher number of mitochondria. CONCLUSION: These results indicated that peroxynitrite could cause oxidative damage to the cochlear hair cells, and low concentrations of Wnt3a has a protective effect against oxidative damage. LEVEL OF EVIDENCE: Level 2.


Assuntos
Células Ciliadas Auditivas , Ácido Peroxinitroso , Camundongos , Animais , Ácido Peroxinitroso/metabolismo , Ácido Peroxinitroso/farmacologia , Camundongos Endogâmicos C57BL , Estresse Oxidativo
18.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): m611-2, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22590114

RESUMO

In the title compound, [Ag(C(7)H(7)O(3)S)(C(13)H(14)N(2))](n), the Ag(I) ion is coordinated in a T-shape by two N atoms from two symmetry-related 1,3-bis-(pyridin-4-yl)propane ligands and one O atom from a p-toluene-sulfonate ligand, forming a one-dimensional zigzag chain along [001]. In the crystal, weak C-H⋯O hydrogen bonds and weak Ag⋯Ag inter-actions [3.2628 (5) Å] are observed.

19.
Front Genet ; 13: 863617, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464858

RESUMO

Convergent evolution between distantly related taxa often mirrors adaptation to similar environments. Rust fungi and anther smuts, which belong to different classes in Pucciniomycotina, have independently evolved a phytoparasitic lifestyle, representing an example of convergent evolution in the fungal kingdom. To investigate their adaptations and the genetic bases underlying their phytoparasitic lifestyles, we performed genome-wide convergence analysis of amino acid substitutions, evolutionary rates, and gene gains and losses. Convergent substitutions were detected in ATPeV0D and RP-S27Ae, two genes important for the generation of turgor pressure and ribosomal biosynthesis, respectively. A total of 51 positively selected genes were identified, including eight genes associated with translation and three genes related to the secretion pathway. In addition, rust fungi and anther smuts contained more proteins associated with oligopeptide transporters and vacuolar proteases than did other fungi. For rust fungi and anther smuts, these forms of convergence suggest four adaptive mechanisms for a phytoparasitic lifestyle: 1) reducing the metabolic demand for hyphal growth and penetration at the pre-penetration stage, 2) maintaining the efficiency of protein synthesis during colonization, 3) ensuring the normal secretion of rapidly evolving secreted proteins, and 4) improving the capacity for oligopeptide metabolism. Our results are the first to shed light on the genetic convergence mechanisms and molecular adaptation underlying phytoparasitic lifestyles in fungi.

20.
Rev Sci Instrum ; 93(12): 124501, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586907

RESUMO

With the increasing development of unconventional reservoirs around the world, there is an increasing need to enhance the level of geological characterization. Obviously, since the well loggings are one of the most important data to obtain a fine-scale reservoir model, obtaining well loggings with sufficiently high vertical resolution has always been an important issue and challenge. Therefore, due to its low cost and less time-consuming, employing an advanced signal processing technique to enhance the vertical resolution of loggings has always been a research hotspot in the relevant literature. However, non-homogeneity of the target reservoir is not taken into account in the traditional methods such as vertical resolution matching and spline function interpolation. Furthermore, for state-of-the-art methods that employ different versions of shallow or deep machine learning models, how to adequately exploit the multi-scale shape and temporal information in the employed loggings has been a very challenging problem. To address the above problems, by combining the fractal theory with the long short-term memory network technique, a novel multi-view and multi-scale logging resolution enhancing method was proposed in this paper to make full use of the self-shape-similarity and temporal correlation information in the logging data. Experimental results show that, compared with bi-cubic linear interpolation, sparse representation, super-resolution convolutional neural network and random forest, more promising supper-resolution results can be obtained using the proposed method.

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