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1.
Ann Clin Microbiol Antimicrob ; 23(1): 65, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026373

RESUMO

BACKGROUND: To evaluate the performance of simultaneous amplification and testing (SAT) assay for the detection of group B Streptococcus (GBS) in maternal vaginal and perianal swabs compared with real-time polymerase chain reaction (RT-PCR). METHODS: We obtained vaginal and perianal swabs from 1474 pregnant women at the Obstetrics and Gynecology Hospital of Fudan University (Shanghai, China) between April 2023 and June 2023. Vaginal and perianal swabs were collected at 35-37 weeks of gestation. Swabs were tested for GBS simultaneously by using the SAT assay and RT-PCR, and a comparative analysis (kappa coefficient) was performed. Furthermore, we conducted additional droplet digital PCR (ddPCR) tests to confirm the results when there were controversial results between SAT and RT-PCR. In addition, we compared the limit of detection, technical specificity, repeatability and reproducibility of SAT-GBS with those of routine RT-PCR assays. RESULTS: In our study, the detection rate of clinical GBS according to the SAT assay was 11.5% (169/1471). The SAT assay showed a sensitivity of 91.8%, a specificity of 99.9%, a diagnostic accuracy of 98.9%, a positive predictive value (PPV) of 99.4% and a negative predictive value (NPV) of 98.8%. The kappa value between RT-PCR and SAT was 0.917. CONCLUSIONS: This SAT assay for the detection of group B Streptococcus is not only easy to perform but can also detect GBS sensitively and specifically and may be used in the regular molecular diagnosis of GBS infection among pregnancies.


Assuntos
Complicações Infecciosas na Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Infecções Estreptocócicas , Streptococcus agalactiae , Vagina , Humanos , Feminino , Streptococcus agalactiae/genética , Streptococcus agalactiae/isolamento & purificação , Gravidez , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Vagina/microbiologia , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/microbiologia , Reprodutibilidade dos Testes , Adulto , China , Técnicas de Amplificação de Ácido Nucleico/métodos
2.
Int J Mol Sci ; 25(2)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38255839

RESUMO

Methyl jasmonate (MJA), a signaling molecule in stress pathways, can be used to induce secondary metabolite synthesis in plants. The present study examines its effects on the growth of Salvia viridis hairy roots, and the accumulation of bioactive compounds, and correlates it with the expression of genes involved in the phenylpropanoid pathway. To our knowledge, this study represents the first exploration of elicitation in S. viridis culture and the first comprehensive analysis of MJA's influence on such a wide array of genes within the polyphenol metabolic pathway in the Salvia genus. Plants were treated with 50 and 100 µM MJA, and samples were collected at intervals of one, three, five, and seven days post-elicitation. HPLC analysis revealed that MJA stimulated the accumulation of all tested compounds, with a 30% increase (38.65 mg/g dry weight) in total polyphenol content (TPC) on day five. Quantitative real-time polymerase chain reaction (RT-PCR) analysis demonstrated a significant increase in the expression of the phenylpropanoid pathway genes-TAT (tyrosine aminotransferase), HPPR (4-hydroxyphenylpyruvate reductase), PAL (phenylalanine ammonia-lyase), C4H (cinnamic acid 4-hydroxylase), 4CL (4-coumarate-CoA ligase), and RAS (rosmarinic acid synthase)-following MJA treatment. For the majority of the genes, this increase was observed after the first day of treatment. Importantly, our present results confirm strong correlations of the analyzed gene expression with polyphenol biosynthesis. These findings support the notion that hairy roots provide a promising biotechnological framework for augmenting polyphenol production. Additionally, the combination of elicitor treatment and transgenic technology emerges as a viable strategy to enhance the biosynthesis of these valuable metabolites.


Assuntos
Acetatos , Biotecnologia , Ciclopentanos , Oxilipinas , Acetatos/farmacologia , Cromatografia Líquida de Alta Pressão , Expressão Gênica
3.
Ceska Gynekol ; 89(4): 269-277, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39242201

RESUMO

OBJECTIVE: Endometrial polyp (EP) is a type of pathology that is quite common in clinical practice. Although its exact etiology is not fully known, there is evidence to support that it is sensitive to hormonal stimuli. We aimed to investigate the relationship between kisspeptin (KP) and EP by comparing the genetic (tissue-blood) and immunohistochemical (IHC) expression of KP in EP lesions in patients with normal endometrial findings. MATERIALS AND METHODS: A prospective case-control study of 50 patients with EP (N = 25) and normal endometrial findings (N = 25) on biopsy and/or excision material was performed. Blood and biopsy samples obtained from all patients were stored at -80 °C. KP gene expression levels were determined from paraffin blocks, and peripheral venous blood samples obtained from biopsy specimens and IHC-H-score analysis were performed from paraffin blocks. EP and matched controls were compared for KP. RESULTS: After IHC, the KP H-score of the control group was higher than the EP group, and this difference was statistically significant; H-score: control: 5 (++; 1-15); polyp: 1 (+; 0-12) (P < 0.05). Although KP expression in both tissue and blood was higher in the control group than in the EP group, this difference was not statistically significant (P > 0.05). No significant correlation was found between IHC H-score and KP expression levels in tissue and blood. According to the ROC analysis, the tissue and blood KP expression cut-off value and area under the curve (AUC) predicting the likelihood of developing EP were not significant (tissue KP: 1.04, AUC: 0.570, P = 0.388, sensitivity 56%, specificity 60%, Blood KP: 1.06, AUC: 0.569, P = 0.401, sensitivity 80%, specificity 40%). CONCLUSIONS: Decreased KP expression level in EP lesions may predict the diagnosis of EP, and in the future, KP may have therapeutic potential for benign gynecological pathologies such as polyps.


Assuntos
Imuno-Histoquímica , Kisspeptinas , Pólipos , Humanos , Feminino , Pólipos/genética , Pólipos/metabolismo , Pólipos/patologia , Kisspeptinas/genética , Kisspeptinas/metabolismo , Estudos de Casos e Controles , Doenças Uterinas/genética , Doenças Uterinas/metabolismo , Doenças Uterinas/patologia , Doenças Uterinas/sangue , Estudos Prospectivos , Adulto , Endométrio/metabolismo , Endométrio/patologia , Pessoa de Meia-Idade
4.
J Med Virol ; 94(3): 1009-1019, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34676574

RESUMO

Rapid and reliable detection of severe acute respiratory syndrome coronavirus 2 mutations are significant to control the contagion and spread rate of the virus. We aimed to evaluate the N501Y mutation rate in randomly chosen positive patients with the polymerase chain reaction (PCR). The evaluation and analysis of the data with a retrospective approach in cases with mutations, in terms of public health, will contribute to the literature on the global pandemic that affects our society. Public health authorities will take the necessary precautions and evaluate the current situation. The N501Y mutation was detected in patients with positive Covid-19 PCR test results. The positive samples were examined based on the 6-carboxy-fluorescein (FAM) channel in reverse transcription PCR (RT-PCR) quantitation cycle (Cq) values as low Cq (<25), medium Cq (25-32), and high Cq (32-38) groups. In the study, 2757 (19.7%) of 13 972 cases were detected as mutation suspects and 159 (5.8%) of them were found to have mutations. The ages of the cases with mutations ranged from 1 to 88 years (mean age of 40.99 ± 17.55). 49.7% (n = 79) of the cases with mutations were male, and 50.3% (n = 80) were female. When the RT-PCR-Cq results were examined, it was seen that it varied between 11.3 and 35.03, with an average of 20.75 ± 3.32.


Assuntos
COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Teste de Ácido Nucleico para COVID-19 , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Adulto Jovem
5.
Microb Pathog ; 162: 105304, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34818576

RESUMO

BACKGROUND: Epithelial-mesenchymal transition (EMT) has a fundamental role in tumor initiation, progression, and metastasis. Helicobacter pylori (HP) induces EMT and thus causes gastric cancer (GC) by deregulating multiple signaling pathways involved in EMT. TWIST1 and MAML1 have been confirmed to be critical inducers of EMT via diverse signaling pathways such as Notch signaling. This study aimed to investigate for the first time possible associations between TWIST1/MAML1 mRNA expression levels, HP infection, and clinicopathological characteristics in GC patients. METHOD: TWIST1 and MAML1 mRNA expression levels were evaluated in tumoral and adjacent normal tissues in 73 GC patients using the quantitative reverse transcription PCR (RT-qPCR) method. PCR technique was also applied to examine the infection with HP in GC samples. RESULTS: Upregulation of TWIST1 and MAML1 expression was observed in 35 (48%) and 34 (46.6%) of 73 tumor samples, respectively. Co-overexpression of these genes was found in 26 of 73 (35.6%) tumor samples; meanwhile, there was a significant positive correlation between MAML1 and TWIST1 mRNA expression levels (P < 0.001). MAML1 overexpression exhibited meaningful associations with advanced tumor stages (P = 0.006) and nodal metastases (P ˂ 0.001). 34 of 73 (46.6%) tumors tested positive for HP, and meanwhile, MAML1 expression was positively related with T (P = 0.05) and grade (P = 0.0001) in these HP-positive samples. Increased TWIST1 expression was correlated with patient sex (P = 0.035) and advanced tumor grade (P = 0.017) in HP-infected tumors. Furthermore, TWIST1 and MAML1 expression levels were inversely linked with histologic grade in HP-negative tumor samples (P = 0.021 and P = 0.048, respectively). CONCLUSION: We propose TWIST1 and MAML1 as potential biomarkers of advanced-stage GC that determine the characteristics and aggressiveness of the disease. Based on accumulating evidence and our findings, they can be introduced as promising therapeutic targets to modify functional abnormalities in cells that promote GC progression. Moreover, HP may enhance GC growth and metastasis by disrupting TWIS1/MAML1 expression patterns and related pathways.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Proteínas de Ligação a DNA , Transição Epitelial-Mesenquimal , Helicobacter pylori/genética , Humanos , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Proteína 1 Relacionada a Twist/genética , Regulação para Cima
6.
Mol Biol Rep ; 49(6): 4841-4848, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35344115

RESUMO

BACKGROUND: The stability of the housekeeping gene (HKG) expression is an absolute prerequisite for accurate normalization of target gene expression in a quantitative real-time polymerase chain reaction (RQ-PCR). In RQ-PCR, the widely used normalization approach involves the standardization of target genes to the most stable HKG control genes. According to the recent literature, in different experimental conditions the HKGs exhibit either up or down-regulation and thus affecting the gene expression profiles of target genes which leads to erroneous results. This implies that it is very important to select the appropriate HKG and verify the expression stability of the HKG before quantification of the target gene. METHODS AND RESULTS: The present study aims to analyze six different HKGs for their expression profiles and stability in BCR-ABL1 negative cases and validate them in BCR-ABL1 positive cases, detected by multiplex reverse transcribed polymerase chain reaction (RT-PCR). Six commonly used reference genes (GAPDH, ABL1, RNA18S, ACTB, GUSB, and EEF2) were selected in this study. RQ-PCR was performed on 24 BCR-ABL1 negative cases and the outcomes were validated on 24 BCR-ABL1 positive cases. RefFinder™, a web-based composite software was used to check the stability of HKG genes by different algorithms and comprehensive ranking of each HKG gene in BCR-ABL1 negative cases and finally validated in BCR-ABL1 positive cases. CONCLUSIONS: It was found that RNA18S, ABL1 and GUSB are good stable HKG genes, which showed minimum variability in gene expression compared to GAPDH, EEF2, and ACTB, the most commonly used HKG.


Assuntos
Genes Essenciais , Leucemia-Linfoma Linfoblástico de Células Precursoras , Proteínas de Fusão bcr-abl/genética , Expressão Gênica , Genes Essenciais/genética , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Padrões de Referência
7.
Arch Insect Biochem Physiol ; 110(1): e21873, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35112397

RESUMO

Phosphoacetyl glucosamine mutase (PGM) is the key gene for glycolysis of important metabolic pathways in silkworm, and H2 S (7.5 µM) can promote the growth and development of silkworm. Herein, we used body cavity injection of small-interfering RNA (siRNA) to interfere with the PGM gene in H2 S-treated silkworms. After RNA interference (RNAi), we investigated the growth and development of the silkworm. H2 S treatment could significantly recover the inhibition of body weight, cocoon weight, cocoon shell weight, and cocoon shell ratio by knocking down PGM gene in silkworm, without significant effects on eggs laying and production, and then analyzed the mRNA expression of PGM gene. The interference of siRNA significantly decreased the expression of targeted PGM gene and was concentrated in 48 h followed by gradual recovery. Three interference fragments also showed different interference effects, and siRNA of PGM-3 exerted the highest interference effect to the target gene expression. Fat body had the highest mRNA expression of PGM gene, and the best interference effect was observed after siRNA injection. The results showed that the gene based on H2 S treatment may have an important impact on the growth and development of silkworm by affecting its metabolic pathway.


Assuntos
Bombyx , Sulfeto de Hidrogênio , Animais , Bombyx/metabolismo , Técnicas de Silenciamento de Genes , Glucosamina/metabolismo , Glucosamina/farmacologia , Crescimento e Desenvolvimento , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo
8.
Int J Mol Sci ; 23(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35328631

RESUMO

Agasicles hygrophila is a classical biological agent used to control alligator weed (Alternanthera philoxeroides). Previous research has indicated that the heat shock factor (HSF) is involved in regulating the transcriptional expression of Hsp70 in response to heat resistance in A. hygrophila. However, the regulatory mechanism by which AhHsf regulates the expression of AhHsp70 remains largely unknown. Here, we identified and cloned a 944 bp AhHsp70 promoter (AhHsp70p) region from A. hygrophila. Subsequent bioinformatics analysis revealed that the AhHsp70p sequence contains multiple functional elements and has a common TATA box approximately 30 bp upstream of the transcription start site, with transcription commencing at a purine base approximately 137 bp upstream of ATG. Promoter deletion analyses revealed that the sequence from -944 to -744 bp was the core regulatory region. A dual-luciferase reporter assay indicated that overexpressed AhHsf significantly enhanced the activity of AhHsp70p. Furthermore, qPCR showed that AhHsp70 expression increased with time in Spodoptera frugiperda (Sf9) cells, and AhHsf overexpression significantly upregulated AhHsp70 expression in vitro. Characterization of the upstream regulatory mechanisms demonstrated that AhHsf binds to upstream cis-acting elements in the promoter region of AhHsp70 from -944 to -744 bp to activate the AhHSF-AhHSP pathway at the transcriptional level to protect A. hygrophila from high temperature damage. Furthermore, we proposed a molecular model of AhHsf modulation of AhHsp70 transcription following heat shock in A. hygrophila. The findings of this study suggest that enhancing the heat tolerance of A. hygrophila by modulating the upstream pathways of the Hsp family can improve the biocontrol of A. philoxeroides.


Assuntos
Acanthaceae , Amaranthaceae , Besouros , Termotolerância , Animais , Besouros/fisiologia , Termotolerância/genética , Fatores de Transcrição/genética
9.
Klin Lab Diagn ; 67(1): 59-64, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35077072

RESUMO

Early diagnosis of tick-borne borreliosis determines the indications for etiotropic therapy, and the detection of borrelia in a tick that has bitten you serves as the basis for antibiotic prophylaxis. To determine the causative agent of borreliosis, PCR methods are most widely used, which requires special conditions for organizing the work of laboratories and the use of expensive equipment. In addition, the procedure for isolating bacterial DNA and subsequent amplification takes several hours of working time. At the same time, methods for detecting borrelia in the isothermal LAMP-reaction are described, which makes it possible to significantly speed up the diagnosis, does not require complex equipment and highly qualified personnel. It is also known that LAMP in some cases allows analysis without prior extraction of nucleic acids. The purpose was a development of a modified test for isothermal detection of DNA of borreliosis pathogens for an accelerated result and the possibility of excluding the stage of nucleic acid extraction. We used 40 samples of Borrelia DNA and 11 Ixodes persulcatus ticks. To shorten the detection time for Borrelia, the previously described LAMP method was modified by the introduction of additional loop primers. The copy number of the positive DNA sample of the borrelia plasmid was estimated using digital PCR. The results of the LAMP reaction were compared with those of the commercial PRC-RT test. The additional use of loop primers approximately halved the detection time for Borrelia DNA without affecting the comparative diagnostic efficiency. The analytical sensitivity limit of the modified LAMP method was 4 copies/µl or 21 molecules of the plasmid standard added to the reaction. In comparative testing with RT-PCR, the sensitivity of the LAMP method is 90%, and the specificity is 100%. The possibility of detecting borrelia in ticks without the stage of DNA extraction has been demonstrated for the first time. A modified isothermal method for the detection of pathogens of tick-borne borreliosis has been developed, which allows analysis within 20-30 minutes, including in ticks without preliminary DNA extraction.


Assuntos
Borrelia , Ixodes , Animais , Borrelia/genética , Primers do DNA , DNA Bacteriano/genética , Reação em Cadeia da Polimerase
10.
Klin Lab Diagn ; 67(3): 170-176, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35320633

RESUMO

The paper presents the results of a study of the prevalence of Ixodid ticks - potential carriers of tick-borne rickettsiosis pathogens. Ectoparasites were collected in various natural and climatic zones of the Crimean Peninsula within the year 2016-2018. As a result of screening with the help of real-time PCR analysis (PCR-RT), a genetic marker (a section of the gltA gene) of the rickettsia group of tick-borne spotted fever was detected in ticks. The most common DNA marker of rickettsia was found in ticks in the eastern regions of the steppe zone - 50,6 %, in the north-western part of the steppe zone this value was 12,0 %. The least amount of rickettsia target DNA was detected in ticks collected in the mountain forest and south bank zones - 4,5 %. As a result of sequencing of positive DNA samples from fragments of the gltA, ompA, ompB, and sca4 genes, the species composition of rickettsias was established. The DNA of 8 species of rickettsia was identified: Circulation of three R. conorii, R. massiliae, R. sibirica subsp. mongolotimonae, R. slovaca, R. aeschlimannii, R. monacensis, R. helvetica, R. raoultii. R. massiliae, R. slovaca, and R. helvetica were established in the Crimean Peninsula for the first time. The peculiarities of the geographical distribution of the identified rickettsia species were determined, which was due to the spread of mites-carriers of pathogens. The revealed diversity of rickettsia species and their vectors, due to the isolation of the areas of the main feeding animals and the established routes of migratory birds, suggests the circulation of other rickettsia species on the territory of the Crimean Peninsula. The obtained results suggest that the diseases of tick-borne rickettsiosis in the Crimean Peninsula can be caused not only by R. conorii, as previously thought, but also by other types of rickettsii.


Assuntos
Infecções por Rickettsia , Rickettsia , Carrapatos , Animais , Humanos , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Rickettsia/genética , Carrapatos/genética , Carrapatos/microbiologia
11.
Ann Clin Microbiol Antimicrob ; 20(1): 38, 2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34022903

RESUMO

BACKGROUND: SARS-CoV-2 is a newly emerged coronavirus, causing the coronavirus disease 2019 (COVID-19) outbreak in December, 2019. As drugs and vaccines of COVID-19 remain in development, accurate virus detection plays a crucial role in the current public health crisis. Quantitative real-time reverse transcriptase-polymerase chain reaction (RT-qPCR) kits have been reliably used for detection of SARS-CoV-2 RNA since the beginning of the COVID-19 outbreak, whereas isothermal nucleic acid amplification-based point-of-care automated kits have also been considered as a simpler and rapid alternative. However, as these kits have only been developed and applied clinically within a short timeframe, their clinical performance has not been adequately evaluated to date. We describe a comparative study between a newly developed cross-priming isothermal amplification (CPA) kit (Kit A) and five RT-qPCR kits (Kits B-F) to evaluate their sensitivity, specificity, predictive values and accuracy. METHODS: Fifty-two clinical samples were used including throat swabs (n = 30), nasal swabs (n = 7), nasopharyngeal swabs (n = 7) and sputum specimens (n = 8), comprising confirmed (n = 26) and negative cases (n = 26). SARS-CoV-2 detection was simultaneously performed on each sample using six nucleic acid amplification kits. The sensitivity, specificity, positive/negative predictive values (PPV/NPV) and the accuracy for each kit were assessed using clinical manifestation and molecular diagnoses as the reference standard. Reproducibility for RT-qPCR kits was evaluated in triplicate by three different operators using a SARS-CoV-2 RNA-positive sample. On the basis of the six kits' evaluation results, CPA kit (Kit A) and two RT-qPCR Kits (Kit B and F) were applied to the SARS-CoV-2 detection in close-contacts of COVID-19 patients. RESULTS: For Kit A, the sensitivity, specificity, PPV/NPV and accuracy were 100%. Among the five RT-qPCR kits, Kits B, C and F had good agreement with the clinical diagnostic reports (Kappa ≥ 0.75); Kits D and E were less congruent (0.4 ≤ Kappa < 0.75). Differences between all kits were statistically significant (P < 0.001). The reproducibility of RT-qPCR kits was determined using a coefficients of variation (CV) between 0.95% and 2.57%, indicating good reproducibility. CONCLUSIONS: This is the first comparative study to evaluate CPA and RT-qPCR kits' specificity and sensitivity for SARS-CoV-2 detection, and could serve as a reference for clinical laboratories, thus informing testing protocols amid the rapidly progressing COVID-19 pandemic.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , Kit de Reagentes para Diagnóstico , SARS-CoV-2/genética , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Food Microbiol ; 99: 103816, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119101

RESUMO

Protozoan contamination in produce is of growing importance due to their capacity to cause illnesses in consumers of fresh leafy greens. Viability assays are essential to accurately estimate health risk caused by viable parasites that contaminate food. We evaluated the efficacy of reverse transcription quantitative PCR (RT-qPCR), propidium monoazide coupled with (q)PCR, and viability staining using propidium iodide through systematic laboratory spiking experiments for selective detection of viable Cryptosporidium parvum, Giardia enterica, and Toxoplasma gondii. In the presence of only viable protozoa, the RT-qPCR assays could accurately detect two to nine (oo)cysts/g spinach (in 10 g processed). When different proportions of viable and inactivated parasite were spiked, mRNA concentrations correlated with increasing proportions of viable (oo)cysts, although low levels of false-positive mRNA signals were detectable in the presence of high amounts of inactivated protozoa. Our study demonstrated that among the methods tested, RT-qPCR performed more effectively to discriminate viable from inactivated C. parvum, G. enterica and T. gondii on spinach. This application of viability methods on leafy greens can be adopted by the produce industry and regulatory agencies charged with protection of human public health to screen leafy greens for the presence of viable protozoan pathogen contamination.


Assuntos
Cryptosporidium parvum/isolamento & purificação , Parasitologia de Alimentos/métodos , Giardia/isolamento & purificação , Spinacia oleracea/parasitologia , Toxoplasma/isolamento & purificação , Animais , Azidas/química , Cryptosporidium parvum/química , Cryptosporidium parvum/genética , Cryptosporidium parvum/crescimento & desenvolvimento , Contaminação de Alimentos/análise , Giardia/química , Giardia/genética , Giardia/crescimento & desenvolvimento , Oocistos/química , Oocistos/crescimento & desenvolvimento , Oocistos/isolamento & purificação , Folhas de Planta/parasitologia , Propídio/análogos & derivados , Propídio/química , Reação em Cadeia da Polimerase em Tempo Real , Coloração e Rotulagem , Toxoplasma/química , Toxoplasma/genética , Toxoplasma/crescimento & desenvolvimento
13.
J Clin Microbiol ; 58(8)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32381643

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as the cause of a worldwide pandemic. Many commercial SARS-CoV-2 reverse transcription-PCR (RT-PCR) assays have received Emergency Use Authorization from the U.S. Food and Drug Administration. However, there are limited data describing their performance, in particular the performance of high-throughput SARS-CoV-2 RT-PCR systems. We analyzed the diagnostic performance of two high-throughput systems: cobas 6800 and Panther Fusion, and their associated RT-PCR assays, with a collection of 389 nasopharyngeal specimens. The overall agreement between the platforms was 96.4% (375/389). Cohen's kappa analysis rated the strength of agreement between the two platforms as "almost perfect" (κ = 0.922; standard error, 0.051). Furthermore, there was no significant difference between corresponding cycle threshold values generated on the two systems (P value = 0.88; Student's t test). Taken together, these data imply that the two platforms can be considered comparable in terms of their clinical performance. We believe that this information will be useful for those who have already adopted these platforms or are seeking to implement high-throughput RT-PCR testing to stem the SARS-CoV-2 pandemic.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Ensaios de Triagem em Larga Escala , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Betacoronavirus/genética , COVID-19 , Infecções por Coronavirus/virologia , Humanos , Nasofaringe/virologia , Pandemias , Pneumonia Viral/virologia , SARS-CoV-2 , Estados Unidos
14.
Vopr Pitan ; 89(3): 62-70, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32790259

RESUMO

One of the ways to improve the laboratory control methodology of genetically modified organisms of plant origin (GMO) is to use multiplexing - an approach that allows you to increase the number of targets and enlarge the number of simultaneously processed samples, maximizing the potential of polymerase chain reaction in real time (PCR-RT). The aim of the study is to develop a quantitative identification protocol for genetically engineered (GE) potato event AV43-6-G7 in the format of duplex PCR-RT with the use of TaqMan® PCR technology. Material and methods. The duplex system included 2 types of specific DNA-primers and fluorescence-labeled probes: the first one is for detection of transformation event AV43- 6-G7 DNA sequence, the second is for detection of Stp23 taxon-specific potato gene. PCR parameters were chosen by empirical selection of concentrations of primers and probes, Mg2+ ions, deoxyribonucleotides, stabilizing agent for polymerase, as well as primer annealing temperature and incubation duration for each stage of the cycle. Results. As a result of these studies, the composition of the reaction mixture was optimized for the detection and quantification of GE potato event AV43-6-G7 in food. Oligonucleotide primers and fluorescent probes were selected. The compositions of reaction mixtures and temperature-time parameters of PCR were tested: 2.5-fold reaction buffer for PCR-RT in the presence of ROX (carboxy-X-rhodamine), specific to the GE component primers (AV43-6-G7-f/AV43-6-G7-r) and target taxon (GRF3/ GRR3) at 300 nM/300 nM and 100 nM/100 nM, probes at 200 nM and 200 nM, respectively; bovine serum albumin - 0.04%; MgCl2 - 3.5 mM, deoxynucleoside triphosphates - 0.3 mM, as well as the temperature-time profile of the reaction (initial denaturation of 95 °C - 5 min, followed by 45 cycles: 95 °Ð¡ - 20 sec, 58 °Ð¡ - 20 sec, 62 °Ð¡ - 40 sec). Conclusion. The validity of the developed method is confirmed by laboratory studies and testifies to its reliability.


Assuntos
Reação em Cadeia da Polimerase Multiplex , Plantas Geneticamente Modificadas/genética , Solanum tuberosum/genética , DNA de Plantas , Reprodutibilidade dos Testes
15.
BMC Genomics ; 20(1): 772, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31651257

RESUMO

BACKGROUND: Abiotic stresses due to climate change pose a great threat to crop production. Heat shock transcription factors (HSFs) are vital regulators that play key roles in protecting plants against various abiotic stresses. Therefore, the identification and characterization of HSFs is imperative to dissect the mechanism responsible for plant stress responses. Although the HSF gene family has been extensively studied in several plant species, its characterization, evolutionary history and expression patterns in the radish (Raphanus sativus L.) remain limited. RESULTS: In this study, 33 RsHSF genes were obtained from the radish genome, which were classified into three main groups based on HSF protein domain structure. Chromosomal localization analysis revealed that 28 of 33 RsHSF genes were located on nine chromosomes, and 10 duplicated RsHSF genes were grouped into eight gene pairs by whole genome duplication (WGD). Moreover, there were 23 or 9 pairs of orthologous HSFs were identified between radish and Arabidopsis or rice, respectively. Comparative analysis revealed a close relationship among radish, Chinese cabbage and Arabidopsis. RNA-seq data showed that eight RsHSF genes including RsHSF-03, were highly expressed in the leaf, root, cortex, cambium and xylem, indicating that these genes might be involved in plant growth and development. Further, quantitative real-time polymerase chain reaction (RT-qPCR) indicated that the expression patterns of 12 RsHSF genes varied upon exposure to different abiotic stresses including heat, salt, and heavy metals. These results indicated that the RsHSFs may be involved in abiotic stress response. CONCLUSIONS: These results could provide fundamental insights into the characteristics and evolution of the HSF family and facilitate further dissection of the molecular mechanism responsible for radish abiotic stress responses.


Assuntos
Evolução Molecular , Genômica , Fatores de Transcrição de Choque Térmico/genética , Raphanus/genética , Raphanus/fisiologia , Estresse Fisiológico/genética , Cromossomos de Plantas/genética , Sequência Conservada , Éxons/genética , Duplicação Gênica/genética , Íntrons/genética , Motivos de Nucleotídeos/genética , Filogenia
16.
Mol Biol Rep ; 46(1): 933-945, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30560406

RESUMO

Polyploidy is an important evolutionary factor in most land plant lineages which possess more than two complete sets of chromosomes. Radish (Raphanus sativus L.) is an economically annual/biennial root vegetable crop worldwide. However, the expression patterns of duplicated homologs involved in the autopolyploidization remains unclear. In present study, the autotetraploid radish plants (2n = 4x = 36) were produced with colchicine and exhibited an increase in the size of flowers, leaves, stomata and pollen grains. The differential gene expression (DGE) profiling was performed to investigate the differences in gene expression patterns between diploid and its corresponding autotetraploid by RNA-Sequencing (RNA-Seq). Totally, 483 up-regulated differentially expressed genes (DEGs) and 408 down-regulated DEGs were detected in diploid and autotetraploid radishes, which majorly involved in the pathways of hormones, photosynthesis and stress response. Moreover, the xyloglucan endotransglucosylase/hydrolase (XTH) and pectin methylesterases (PME) family members related to cell enlargement and cell wall construction were found to be enriched in GO enrichment analysis, of which XTH family members enriched in "apoplast" and "cell wall" terms, while PME family members enriched in "cell wall" term. Reverse-transcription quantitative PCR (RT-qPCR) analysis indicated that the expression profile of DEGs were consistent with results from the RNA-Seq analysis. The DEGs involved in cell wall construction and auxin metabolism were predicted to be associated with organs size increase of autotetraploid radishes in the present study. These results could provide valuable information for elucidating the molecular mechanism underlying polyploidization and facilitating further genetic improvements of important traits in radish breeding programs.


Assuntos
Diploide , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Poliploidia , Raphanus/genética , Transcriptoma/genética , Regulação para Baixo/genética , Ontologia Genética , Raphanus/anatomia & histologia , Raphanus/citologia , Reprodutibilidade dos Testes , Regulação para Cima/genética
17.
J Clin Lab Anal ; 33(9): e23003, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31541491

RESUMO

PURPOSE: To identify potential molecular targets for lung cancer intervention and diagnosis, we analyzed the differential miRNA expression of peripheral blood between lung cancer patients and healthy controls. METHODS: Three pairs of cases' and controls' peripheral blood samples were evaluated for miRNA expression by microarray. 12 miRNAs were selected for RT-PCR validation and target genes prediction. In addition, 4 miRNAs were selected for future validation by RT-PCR in a large sample of 145 cases and 55 frequency-matched healthy controls. RESULTS: A total of 338 differentially expressed miRNAs were screened and identified by microarray. According to the fold changes, the top ten upregulated miRNAs were hsa-miR-124-3p, hsa-miR-379-5p, hsa-miR-3655, hsa-miR-450b-5p, hsa-miR-29a-5p, hsa-miR-200a-3p, hsa-miR-542-3p, hsa-miR-138-5p, hsa-miR-219a-2-3p, and hsa-miR-4701-3p, and the top ten downregulated miRNAs were hsa-miR-34c-5p, hsa-miR-135a-5p, hsa-miR-132-3p, hsa-miR-3178, hsa-miR-4449, hsa-miR-4999-3p, hsa-miR-1246, hsa-miR-4424, hsa-miR-1252-5p, and hsa-miR-24-2-5p. RT-PCR verification of the 12 miRNAs revealed that 5 of 8 upregulated miRNAs, 2 of 4 downregulated miRNAs showed a significant difference between the cases and controls (P < .05). A large number of target genes and their functional set showed overlapping among the 453 predicted target genes of the 12 miRNAs (P < .01). RT-PCR in the large sample confirmed the significant differential expression level of hsa-miR-29a-5p, hsa-miR-135a-5p, hsa-miR-542-3p, and hsa-miR-4491 between cases and controls (P < .05), and three of these microRNA, except hsa-miR-29a-5p, were significant after Bonferroni correction for adjustment of multiple comparisons. CONCLUSION: There was a significant difference in miRNAs expression in the peripheral blood between lung cancer patients and healthy controls, and 4 miRNAs were validated by a large-size sample.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , MicroRNAs/genética , Idoso , Feminino , Ontologia Genética , Redes Reguladoras de Genes , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Transdução de Sinais/genética
18.
Klin Lab Diagn ; 64(11): 686-689, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31747499

RESUMO

Based on experimental studies with 10-fold dilutions of two the strains TBEV of the Far Eastern subtype, different in moleculargenetic characteristic complex data of simultaneously taking into account three indicators of their verification (virus titer, ELISA and PCR-RT) were obtained. The efficiency of detecting a genetic marker in PCR compared with ELISA for a weakly pathogenic strain with defects in the genetic structure was higher by a factor of 10, and for a highly pathogenic strain by a factor of 5,000. At the same time, positive results in both reactions with respect to two strains were detected with a virus titer of not less than 1-1.5 log TCID50, i.e. this level of virus in the sample is defined as epidemically significant. An algorithm for conducting research on the verification of TBEV is proposed: 1) Ticks collected from vegetation can be examined by ELISA or by PCR. All positive results can be summarized and considered viral ticks; 2) All samples with positive results only in PCR or ELISA must be investigated in two reactions in order to obtain confirmation of the possible infectivity of the pathogen; 3) To obtain a fast complex result of infection of the removed ticks from patients or blood after a tick bite, studies should be carried out simultaneously in two reactions simultaneously in ELISA and PCR; 4) Isolation virus should be carried out in biological samples (ticks collected from vegetation, ticks removed from patients, the blood of patients with suspected TBE, mammals) only with the same results in PCR and ELISA. Thus, such an approach to verifying TBEV in a tick or in the blood of patients will improve the reliability of laboratory diagnostics, identifying not only markers of TBEV, but also determining the infectivity of the pathogen, which may be the basis for the appointment of early intensive antiviral therapy.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/genética , Encefalite Transmitida por Carrapatos/diagnóstico , Ixodes/virologia , Animais , Vírus da Encefalite Transmitidos por Carrapatos/patogenicidade , Ensaio de Imunoadsorção Enzimática , Humanos , RNA Viral , Reprodutibilidade dos Testes
19.
BMC Biotechnol ; 18(1): 17, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29554888

RESUMO

BACKGROUND: We demonstrate the feasibility of creating a pair of reference samples to be used as surrogates for clinical samples measured in either a research or clinical laboratory setting. The reference sample paradigm presented and evaluated here is designed to assess the capability of a measurement process to detect true differences between two biological samples. Cell-based reference samples can be created with a biomarker signature pattern designed in silico. Clinical laboratories working in regulated applications are required to participate in proficiency testing programs; research laboratories doing discovery typically do not. These reference samples can be used in proficiency tests or as process controls that allow a laboratory to evaluate and optimize its measurement systems, monitor performance over time (process drift), assess changes in protocols, reagents, and/or personnel, maintain standard operating procedures, and most importantly, provide evidence for quality results. RESULTS: The biomarkers of interest in this study are microRNAs (miRNAs), small non-coding RNAs involved in the regulation of gene expression. Multiple lung cancer associated cell lines were determined by reverse transcription (RT)-PCR to have sufficiently different miRNA profiles to serve as components in mixture designs as reference samples. In silico models based on the component profiles were used to predict miRNA abundance ratios between two different cell line mixtures, providing target values for profiles obtained from in vitro mixtures. Two reference sample types were tested: total RNA mixed after extraction from cell lines, and intact cells mixed prior to RNA extraction. MicroRNA profiling of a pair of samples composed of extracted RNA derived from these cell lines successfully replicated the target values. Mixtures of intact cells from these lines also approximated the target values, demonstrating potential utility as mimics for clinical specimens. Both designs demonstrated their utility as reference samples for inter- or intra-laboratory testing. CONCLUSIONS: Cell-based reference samples can be created for performance assessment of a measurement process from biomolecule extraction through quantitation. Although this study focused on miRNA profiling with RT-PCR using cell lines associated with lung cancer, the paradigm demonstrated here should be extendable to genome-scale platforms and other biomolecular endpoints.


Assuntos
Biomarcadores Tumorais/genética , Técnicas de Laboratório Clínico/normas , MicroRNAs/genética , Pequeno RNA não Traduzido/genética , Análise de Variância , Linhagem Celular Tumoral , Expressão Gênica , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas
20.
Clin Chem Lab Med ; 56(6): 990-1000, 2018 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-29688883

RESUMO

BACKGROUND: MicroRNAs (miRNAs) may function either as oncogenes or tumor suppressors and are heavily involved in the initiation and progression of cancer, and in metastasis of tumor cells. MicroRNA-28-5p (miR-28-5p) targets several cancer-related genes and is hence involved in cell proliferation, migration, invasion and epithelial-mesenchymal transition. In this study, we investigated the potential diagnostic and prognostic significance of miR-28-5p expression in colorectal adenocarcinoma, the most frequent type of colorectal cancer (CRC). METHODS: Therefore, we isolated total RNA from 182 colorectal adenocarcinoma specimens and 86 paired non-cancerous colorectal mucosae. After polyadenylation of 2 µg total RNA and its reverse transcription using an oligo-dT-adapter primer, we quantified miR-28-5p levels using an in-house-developed reverse-transcription real-time quantitative polymerase chain reaction (RT-qPCR) method, based on the SYBR Green chemistry. RESULTS: Comparison of miR-28-5p levels among 86 pairs of colorectal tumors and their adjacent non-cancerous mucosae uncovered the downregulation of miR-28-5p expression in the majority of malignant colorectal tumors. More importantly, high miR-28-5p expression predicts poor disease-free survival (DFS) and overall survival (OS) of colorectal adenocarcinoma patients. Multivariate Cox regression analysis revealed that miR-28-5p overexpression is a significant predictor of poor prognosis in colorectal adenocarcinoma, independent of tumor size, histological grade, TNM staging, radiotherapy and chemotherapy. Interestingly, strong miR-28-5p expression retains its predictive potential regarding relapse among patients with negative regional lymph nodes, and predicts poor OS in patients diagnosed with non-metastatic colorectal adenocarcinoma. CONCLUSIONS: High miR-28-5p expression predicts poor DFS and OS of colorectal adenocarcinoma patients, independently of clinicopathological prognosticators and standard patient treatment, including radiotherapy and chemotherapy.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/patologia , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , MicroRNAs/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida
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