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Chestnut production is considered one of the most important economic resources of rural mountainous areas in Greece. Lately, producers report a steep rise in the incidence of brown rot disease caused by the fungus Gnomoniopsis smithogilvyi (Gnomoniaceae, Diaporthales), which results in severe chestnut rot. The pathogen is considered an emerging pathogen in many countries worldwide (Italy, France, Switzerland, Australia, New Zealand). This study aimed at (a) exploring the incidence of the brown rot disease in Vria (Regional Unit of Pieria, Region of Central Makedonia, Greece), (b) isolating and identifying the causal agent of the disease, (c) exploring the fungus presence at different phenological stages of the chestnut trees, and (d) implementing species-specific Bar- High Resolution Melting Analysis (HRM) for the early detection of G. smithogilvyi in chestnuts. G. smithogilvyi occurrence in chestnut tissues was more severe in June (59 %), nearly disappeared in July (19 %) and August (7 %) and increased again during harvesting time in September (57 %). This result could be attributed to a sum of different factors, including climate conditions. Moreover, it was demonstrated that G. smithogilvyi can be identified using a Bar-HRM analysis of chestnut tissues (buds, flowers and nuts). Results of this study clearly demonstrate that Bar-HRM can be used for the accurate, rapid and reliable identification of G. smithogilvyi universally on infected samples from different localities.
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Ascomicetos , Fagaceae , Flores , Enfermedades de las Plantas , Enfermedades de las Plantas/microbiología , Ascomicetos/aislamiento & purificación , Ascomicetos/genética , Ascomicetos/clasificación , Grecia , Flores/microbiología , Fagaceae/microbiología , IncidenciaRESUMEN
PURPOSE: The current candidate gene association study aims to investigate tag SNPs from the TACR1 gene as pharmacogenetic predictors of response to the antiemetic guidelines-recommended, NK-1 receptor antagonist-based, triple antiemetic regimens. METHODS: A set of eighteen tag SNPs of TACR1 were genotyped in breast cancer patients receiving anthracycline and cyclophosphamide (with/without docetaxel) applying real-time PCR-HRMA. Data analysis for 121 ultimately enrolled patients was initiated by defining haplotype blocks using PHASE v.2.1. The association of each tag SNP and haplotype alleles with failure to achieve the defined antiemetic regimen efficacy endpoints was tested using PLINK (v.1.9 and v.1.07, respectively) based on the logistic regression, adjusting for the previously known chemotherapy-induced nausea and vomiting (CINV) prognostic factors. All reported p-values were corrected using the permutation test (n = 100,000). RESULTS: Four variants of rs881, rs17010730, rs727156, and rs3755462, as well as haplotypes containing the mentioned variants, were significantly associated with failure to achieve at least one of the defined efficacy endpoints. Variant annotation via in-silico studies revealed that the non-seed sequence variant, rs881, is located in the miRNA (hsa-miR-613) binding site. The other three variants or a variant in complete linkage disequilibrium with them overlap a region of high H3K9ac-promoter-like signature or regions of high enhancer-like signature in the brain or gastrointestinal tissue. CONCLUSION: Playing an essential role in regulating TACR1 expression, gene polymorphisms of TACR1 serve as the potential pharmacogenetic predictors of response to the NK-1 receptor antagonist-based, triple antiemetic regimens. If clinically approved, modifying the NK-1 receptor antagonist dose leads to better management of CINV in risk-allele carriers.
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Antieméticos , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama , Ciclofosfamida , Náusea , Polimorfismo de Nucleótido Simple , Receptores de Neuroquinina-1 , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Persona de Mediana Edad , Antieméticos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Receptores de Neuroquinina-1/genética , Náusea/inducido químicamente , Náusea/genética , Ciclofosfamida/efectos adversos , Ciclofosfamida/uso terapéutico , Ciclofosfamida/administración & dosificación , Vómitos/inducido químicamente , Vómitos/genética , Antagonistas del Receptor de Neuroquinina-1/uso terapéutico , Adulto , Estudios de Asociación Genética , Haplotipos , Anciano , Docetaxel/uso terapéutico , Docetaxel/efectos adversos , Farmacogenética , Antraciclinas/efectos adversos , Antraciclinas/uso terapéutico , GenotipoRESUMEN
DNA quantification prior to STR amplification is a crucial step in forensic casework. Obtaining good-quality genetic STR profiles depends mainly on the amount and integrity of the DNA input in the PCR. In addition, the detection of male trace DNA provides key information for forensic investigation. AIM: To evaluate the correlation between the quantification results obtained with the previously developed Amel-Y system, and its ability to detect Y-chromosome DNA by HRM, with the resulting STR profiles, and to ultimately show that Amel-Y can be routinely used in forensic casework to improve STR and Y-STR results. MATERIAL & METHODS: Biological samples derived from forensic casework (85 reference and 391 evidence samples) were quantified by the Amel-Y system (a duplex qPCR/HRM based on SYTO™ 9 chemistry) using Rotor-Gene 6000. STRs were amplified and analyzed with GeneAmp™ PCR System 9700 or Veriti™ Thermal Cyclers and ABI 3500 Genetic Analyzer, respectively. RESULTS: After DNA normalization, a total of 386 STR profiles were obtained (305 full and 81 partial). Sex typing by HRM was 100% successful in reference samples. Male DNA was detected by HRM in 210 evidence samples. 80/201 were mixed with an excess of female DNA. In addition, Amel-Y was able to detect Y-chromosome DNA in mixed samples that did not amplify the Y-variant of Amelogenin marker with commercial STR kits. The reproducibility and precision of the Amel-Y system were demonstrated (CVCt% ≤ 9.55) within the dynamic range analyzed (0.016-50 ng/µL; 41 independent runs). Amel-Y also proved to be compatible with other real-time PCR platforms. CONCLUSION: We demonstrated that Amel-Y is a robust quantification system that can be routinely used in forensic casework to obtain reliable autosomal STR profiles and can be suitable as a predictor for Y-STR typing success when male DNA is detected. HRM can be used as a rapid screening tool for male DNA detection in mixed samples. Alternative designs like Amel-Y offer independence from commercial quantification kits in forensic labs.
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Dermatoglifia del ADN , Repeticiones de Microsatélite , Masculino , Humanos , Femenino , Dermatoglifia del ADN/métodos , Reproducibilidad de los Resultados , ADN/análisis , Cromosomas Humanos YRESUMEN
High-resolution melting (HRM) analysis, a post-polymerase chain reaction (PCR) application in a single closed tube, is the straightforward method for simultaneous detection, genotyping, and mutation scanning, enabling more significant dynamic detection and sequencing-free turnaround time. This study aimed to establish a combined reverse-transcription quantitative PCR and HRM (RT-qPCR-HRM) assay for diagnosing and genotyping feline calicivirus (FCV). This developed method was validated with constructed FCV plasmids, clinical swab samples from living cats, fresh-frozen lung tissues from necropsied cats, and four available FCV vaccines. We performed RT-qPCR to amplify a 99-base pair sequence, targeting a segment between open reading frame (ORF) 1 and ORF2. Subsequently, the HRM assay was promptly applied using Rotor-Gene Q® Software. The results significantly revealed simultaneous detection and genetic discrimination between commercially available FCV vaccine strains, wild-type Thai FCV strains, and VS-FCV strains within a single PCR reaction. There was no cross-reactivity with other feline common viruses, including feline herpesvirus-1, feline coronavirus, feline leukemia virus, feline immunodeficiency virus, and feline morbillivirus. The detection limit of the assay was 6.18 × 101 copies/µl. This study, therefore, is the first demonstration of the uses and benefits of the RT-qPCR-HRM assay for FCV detection and strain differentiation in naturally infected cats.
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Infecciones por Caliciviridae , Calicivirus Felino , Enfermedades de los Gatos , Vacunas , Gatos , Animales , Calicivirus Felino/genética , Infecciones por Caliciviridae/diagnóstico , Infecciones por Caliciviridae/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Mutación , Enfermedades de los Gatos/diagnósticoRESUMEN
To address the shortcomings of current hepatocellular carcinoma (HCC) surveillance tests, we set out to find HCC-specific methylation markers and develop a highly sensitive polymerase chain reaction (PCR)-based method to detect them in circulating cell-free DNA (cfDNA). The analysis of large methylome data revealed that Ring Finger Protein 135 (RNF135) and Lactate Dehydrogenase B (LDHB) are universally applicable HCC methylation markers with no discernible methylation level detected in any other tissue types. These markers were used to develop Methylation Sensitive High-Resolution Analysis (MS-HRM), and their diagnostic accuracy was tested using cfDNA from healthy, at-risk, and HCC patients. The combined MS-HRM RNF135 and LDHB analysis detected 57% of HCC, outperforming the alpha-fetoprotein (AFP) test's sensitivity of 45% at comparable specificity. Furthermore, when used with the AFP test, the methylation assay can detect 70% of HCC. Our findings suggest that the cfDNA methylation assay could be used for HCC liquid biopsy.
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Carcinoma Hepatocelular , Ácidos Nucleicos Libres de Células , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/análisis , alfa-Fetoproteínas/metabolismo , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Metilación de ADN , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Ácidos Nucleicos Libres de Células/genética , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
Coronavirus disease 2019, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses a considerable threat to global public health. This study developed and evaluated a rapid, low-cost, expandable, and sequencing-free high-resolution melting (HRM) assay for the direct detection of SARS-CoV-2 variants. A panel of 64 common bacterial and viral pathogens that can cause respiratory tract infections was employed to evaluate our method's specificity. Serial dilutions of viral isolates determined the sensitivity of the method. Finally, the assay's clinical performance was assessed using 324 clinical samples with potential SARS-CoV-2 infection. Multiplex HRM analysis accurately identified SARS-CoV-2 (as confirmed with parallel reverse transcription-quantitative PCR [qRT-PCR] tests), differentiating between mutations at each marker site within approximately 2 h. For each target, the limit of detection (LOD) was lower than 10 copies/reaction (the LOD of N, G142D, R158G, Y505H, V213G, G446S, S413R, F486V, and S704L was 7.38, 9.72, 9.96, 9.96, 9.50, 7.80, 9.33, 8.25, and 8.25 copies/reaction, respectively). No cross-reactivity occurred with organisms of the specificity testing panel. In terms of variant detection, our results had a 97.9% (47/48) rate of agreement with standard Sanger sequencing. The multiplex HRM assay therefore offers a rapid and simple procedure for detecting SARS-CoV-2 variants. IMPORTANCE In the face of the current severe situation of increasing SARS-CoV-2 variants, we developed an upgraded multiplex HRM method for the predominant SARS-CoV-2 variants based on our original research. This method not only could identify the variants but also could be utilized in subsequent detection of novel variants since the assay has great performance in terms of flexibility. In summary, the upgraded multiplex HRM assay is a rapid, reliable, and economical detection method, which could better screen prevalent virus strains, monitor the epidemic situation, and help to develop measures for the prevention and control of SARS-CoV-2.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Sensibilidad y Especificidad , Reacción en Cadena de la PolimerasaRESUMEN
The genus Thunnus (family Scombridae) comprises eight species of tunas of which all but one are targeted by industrialized fisheries. Although intact individuals of these species can be distinguished by morphological characteristics, researchers and managers often rely on dressed, frozen, juvenile or larval fish samples, which often necessitates the identification of molecular species. Here the authors investigate short amplicon (SA) and unlabelled probe high-resolution melting analysis (UP-HRMA) as a low-cost, high-throughput molecular genotyping assay capable of distinguishing between albacore tuna (Thunnus alalunga), blackfin tuna (Thunnus atlanticus), bigeye tuna (Thunnus obesus), Atlantic bluefin tuna (Thunnus thynnus) and yellowfin tuna (Thunnus albacares) in the Gulf of Mexico. Although SA-HRMA of variable regions in the NADH dehydrogenase subunit 4 (ND4) and subunit 5 (ND5), and subunit 6 (ND6) of the mtDNA genome did yield some species-specific diagnostic melting curves (e.g., ND4 assay can reliably distinguish Atlantic bluefin tuna), genotype masking produced excessive variation in melting curves for reliable multi-species identification. To minimize the genotyping masking of SA-HRMA a 26 base pair long UP containing four SNPs was developed within a 133 bp segment of ND4. The UP-HRMA is able to reliably distinguish Gulf of Mexico species T. thynnus, T. obesus, T. albacares and T. atlanticus by UP melting temperature at 67, 62, 59 and 57°C, respectively. The developed UP-HRMA assay is a lower-cost, higher-throughput, alternative to previously published molecular assays for tuna identification that can be easily automated for large data sets, including ichthyological larval surveys, fisheries specimens lacking distinguishing morphological characteristics or detection of fraudulent trading of tuna species.
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ADN Mitocondrial , Atún , Animales , Atún/genética , Golfo de México , Larva , ADN Mitocondrial/genética , GenotipoRESUMEN
High-resolution melting (HRM) analysis is a simple, fast, and inexpensive real-time polymerase chain reaction (PCR)-based method used to identify genetic variation between populations and detect single-nucleotide polymorphisms (SNPs) in nucleic acid sequences. HRM is a powerful technique that detects the differences between SNP allele melting temperatures by using a fluorescent dye inserted into the duplex deoxyribonucleic acid (DNA) structure. Prior to performing HRM analysis, optimizing the primer design, PCR mixture, and software settings is essential to obtain accurate and reliable results. In this chapter, we describe a detailed SNP genotyping method that includes primer design and the analysis of the shapes and positions of the melt curve of the luminescence intensity of the fluorescent dye attached to amplified DNA using software of qPCR instruments. This protocol is applicable for genotyping germplasm, genetic mapping, and marker-assisted breeding in plants.
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Colorantes Fluorescentes , Fitomejoramiento , Genotipo , Técnicas de Genotipaje/métodos , Polimorfismo de Nucleótido Simple , Reacción en Cadena en Tiempo Real de la Polimerasa , ADN , Desnaturalización de Ácido NucleicoRESUMEN
The present study aimed to detect the prevalence of NOTCH1 c.7541-7542delCT mutation in Egyptian CLL patients using HRM assay and to assess its relation to patients' survival. The study included 50 newly diagnosed treatment-naïve CLL patients and 50 age and sex matched healthy controls. NOTCH1 c.7541-7542delCT mutation was detected using High-resolution melting (HRM) assay and direct Sanger sequencing. Outcome parameters included progression free survival (PFS) and overall survival (OS). NOTCH1 c.7541-7542delCT mutation was detected in 5 (10.0%) of CLL patients. No controls had NOTCH1 c.7541-7542delCT mutation. Similar results were obtained by direct Sanger sequencing yielding a sensitivity and specificity of 100.0% for HRM in detection of NOTCH1 c.7541-7542delCT mutation in the studied patients. In univariate analysis, predictors of OS included Trisomy 12, high LDH, presence of NOTCH1 c.7541-7542delCT mutation and lack of CR. In multivariate analysis, only lack of CR was found as a significant predictor of OS. HRM analysis is a sensitive method for detection of NOTCH1 c.7541-7542delCT mutation in CLL patients. This mutation may be linked to poor disease prognosis.
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The Chilean hazelnut (Gevuina avellana Mol., Proteaceae) is a native tree of Chile and Argentina of edible fruit-type nut. We applied two approaches to contribute to the development of strategies for mitigation of the effects of climate change and anthropic activities in G. avellana. It corresponds to the first report where both tools are integrated, the MaxEnt model to predict the current and future potential distribution coupled with High-Resolution Melting Analysis (HRM) to assess its genetic diversity and understand how the species would respond to these changes. Two global climate models: CNRM-CM6-1 and MIROC-ES2L for four Shared Socioeconomic Pathways: 126, 245, 370, and 585 (2021−2040; 2061−2080) were evaluated. The annual mean temperature (43.7%) and water steam (23.4%) were the key factors for the distribution current of G. avellana (AUC = 0.953). The future prediction model shows to the year 2040 those habitat range decreases at 50% (AUC = 0.918). The genetic structure was investigated in seven natural populations using eight EST-SSR markers, showing a percentage of polymorphic loci between 18.69 and 55.14% and low genetic differentiation between populations (Fst = 0.052; p < 0.001). According to the discriminant analysis of principal components (DAPC) we identified 10 genetic populations. We conclude that high-priority areas for protection correspond to Los Avellanos and Punta de Águila populations due to their greater genetic diversity and allelic richness.
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BACKGROUND: Acute lymphoblastic leukemia is the most prevailing pediatric hematologic malignancy, and various factors such as environmental exposures and genetic variation affect ALL susceptibility and patients outcome. According to genome-wide association studies, several single nucleotide polymorphisms (SNPs) in IKZF1 (rs4132601) and CDKN2A (rs3731249 and rs3731217) genes are associated with ALL susceptibility. Hereupon, this study aimed to discover the association between these SNPs and the risk of childhood ALL among a sample of the Iranian population. METHODS: A total of fifty children with ALL were included in this case-control study, along with an additional fifty healthy children, matched for age and gender. High-resolution melting (HRM) analysis was employed to genotyping rs4132601, rs3731249, and rs3731217. RESULTS: In the patient group, the CT genotype and T allele frequency of rs3731249 were significantly greater than controls (p = 0.01 and p = 0.005, respectively). Moreover, the positive association of CT and dominant model (CT + TT) genotypes and T allele at rs3731249 with the risk of ALL was confirmed (OR = 9.56, OR = 10.76 and OR = 11.00, respectively). There was no significant relation between rs4132601 (IKZF1), rs3731217 (CDKN2A), and childhood ALL. CONCLUSION: The present study indicates that CT genotype and T allele at rs3731249 (CDKN2A) can significantly increase the risk of ALL among children.
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Inhibidor p16 de la Quinasa Dependiente de Ciclina , Estudio de Asociación del Genoma Completo , Factor de Transcripción Ikaros , Leucemia-Linfoma Linfoblástico de Células Precursoras , Estudios de Casos y Controles , Niño , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Factor de Transcripción Ikaros/genética , Irán , Polimorfismo de Nucleótido Simple , Leucemia-Linfoma Linfoblástico de Células Precursoras/genéticaRESUMEN
BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a multifactorial disorder with complicated pathophysiology. Trimethylamine-N-oxide (TMAO) has been thought to be correlated with the pathogenesis of NAFLD. The single nucleotide polymorphisms (SNPs) of hepatic flavin-containing monooxygenase 3 (FMO3) regulate the concentration of TMAO. This case-control study investigated the plasma levels of TMAO as well as its possible correlation with the frequency of specific genotype of FMO3 (-2650C>G, -2543T>A, -2177G>C, -2589C>T, -2106G>A polymorphisms) in Kurdish patients with NAFLD. METHODS AND RESULTS: In 85 confirmed NAFLD patients and 30 healthy individuals, triglycerides (TG), total cholesterol (Chol), low-density lipoprotein (LDL), high-density lipoprotein (HDL), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activities were measured. TMAO was also measured using the LC-MS/MS method. High-resolution melting analysis was applied to determine FMO3 genotypes. Plasma TMAO levels were significantly higher in patients (p = 0.030). A CC genotype with a frequency of 12.9% for SNP -2177G>C was found in Kurdish NAFLD patients. The distribution of the GC genotype was also significantly different (p = 0.017). CONCLUSIONS: The current results provide documentation for high circulatory levels of TMAO and its possible correlation with the presence of the specific genotype -2177G>C FMO3 in Kurdish NAFLD patients.
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Enfermedad del Hígado Graso no Alcohólico , Estudios de Casos y Controles , Cromatografía Liquida , Flavinas , Humanos , Metilaminas , Oxigenasas de Función Mixta , Enfermedad del Hígado Graso no Alcohólico/genética , Óxidos , Oxigenasas , Espectrometría de Masas en TándemRESUMEN
OBJECTIVE: Acute lymphoblastic leukemia (ALL) is one of the most common cancers in children for which the exact pathogenesis is not yet known. Single-nucleotide variants (SNVs) in different DNA repair genes are reported to be associated with ALL risk. This study aimed to determine the association between XRCC1 (rs1799782) and NBN (rs1805794, rs709816) SNVs and childhood ALL risk in a sample of the Iranian population. Fifty children with ALL and 50 age- and sex-matched healthy children were included in this case-control study. Genotyping of the mentioned SNVs was done by high-resolution melting (HRM) analysis. RESULTS: The prevalence of all three SNVs in XRCC1 and NBN genes did not differ between the patient and control groups, and these polymorphisms were not associated with childhood ALL risk (P > 0.05). HRM was a practical method for the detection of SNVs in XRCC1 and NBN genes. We found no significant association between XRCC1 (rs1799782) and NBN (rs1805794, rs709816) SNVs and childhood ALL risk.
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Proteínas de Ciclo Celular/genética , Predisposición Genética a la Enfermedad , Proteínas Nucleares/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X/genética , Estudios de Casos y Controles , Niño , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Genotipo , Humanos , Irán , Polimorfismo de Nucleótido Simple , Leucemia-Linfoma Linfoblástico de Células Precursoras/genéticaRESUMEN
BACKGROUND: The evolution of malaria infection has necessitated the development of highly sensitive diagnostic assays, as well as the use of dried blood spots (DBS) as a potential source of deoxyribonucleic acid (DNA) yield for polymerase chain reaction (PCR) assays. This study identified the different Plasmodium species in malaria-positive patients, and the anti-malarial drug resistance profile for Plasmodium falciparum using DBS samples collected from patients attending Kisoro Hospital in Kisoro district, Southwestern Uganda. METHODS: The blood samples were prospectively collected from patients diagnosed with malaria to make DBS, which were then used to extract DNA for real-time PCR and high-resolution melting (HRM) analysis. Plasmodium species were identified by comparing the control and test samples using HRM-PCR derivative curves. Plasmodium falciparum chloroquine (CQ) resistance transporter (pfcrt) and kelch13 to screen the samples for anti-malarial resistance markers. The HRM-PCR derivative curve was used to present a summary distribution of the different Plasmodium species as well as the anti-malarial drug profile. RESULTS: Of the 152 participants sampled, 98 (64.5%) were females. The average age of the participants was 34.9 years (range: 2 months-81 years). There were 134 samples that showed PCR amplification, confirming the species as Plasmodium. Plasmodium falciparum (N = 122), Plasmodium malariae (N = 6), Plasmodium ovale (N = 4), and Plasmodium vivax (N = 2) were the various Plasmodium species and their proportions. The results showed that 87 (71.3%) of the samples were sensitive strains/wild type (CVMNK), 4 (3.3%) were resistant haplotypes (SVMNT), and 31 (25.4%) were resistant haplotypes (CVIET). Kelch13 C580Y mutation was not detected. CONCLUSION: The community served by Kisoro hospital has a high Plasmodium species burden, according to this study. Plasmodium falciparum was the dominant species, and it has shown that resistance to chloroquine is decreasing in the region. Based on this, molecular identification of Plasmodium species is critical for better clinical management. Besides, DBS is an appropriate medium for DNA preservation and storage for future epidemiological studies.
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Antimaláricos/farmacología , Malaria Falciparum/parasitología , Plasmodium falciparum/efectos de los fármacos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antimaláricos/uso terapéutico , Niño , Preescolar , Resistencia a Medicamentos , Femenino , Humanos , Lactante , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Masculino , Persona de Mediana Edad , Plasmodium falciparum/aislamiento & purificación , Uganda/epidemiología , Adulto JovenRESUMEN
BACKGROUND: Leishmaniasis is endemic in Tunisia and presents with different clinical forms, caused by the species Leishmania infantum, Leishmania major, and Leishmania tropica. The life cycle of Leishmania is complex and involves several phlebotomine sand fly vectors and mammalian reservoir hosts. The aim of this work is the development and evaluation of a high-resolution melting PCR (PCR-HRM) tool to detect and identify Leishmania parasites in wild and domestic hosts, constituting confirmed (dogs and Meriones rodents) or potential (hedgehogs) reservoirs in Tunisia. METHODS: Using in vitro-cultured Leishmania isolates, PCR-HRM reactions were developed targeting the 7SL RNA and HSP70 genes. Animals were captured or sampled in El Kef Governorate, North West Tunisia. DNA was extracted from the liver, spleen, kidney, and heart from hedgehogs (Atelerix algirus) (n = 3) and rodents (Meriones shawi) (n = 7) and from whole blood of dogs (n = 12) that did not present any symptoms of canine leishmaniasis. In total, 52 DNA samples were processed by PCR-HRM using both pairs of primers. RESULTS: The results showed melting curves enabling discrimination of the three Leishmania species present in Tunisia, and were further confirmed by Sanger sequencing. Application of PCR-HRM assays on reservoir host samples showed that overall among the examined samples, 45 were positive, while seven were negative, with no Leishmania infection. Meriones shawi were found infected with L. major, while dogs were infected with L. infantum. However, co-infections with L. major/L. infantum species were detected in four Meriones specimens and in all tested hedgehogs. In addition, multiple infections with the three Leishmania species were found in one hedgehog specimen. Sequence analyses of PCR-HRM products corroborated the Leishmania species found in analyzed samples. CONCLUSIONS: The results of PCR-HRM assays applied to field specimens further support the possibility of hedgehogs as reservoir hosts of Leishmania. In addition, we showed their usefulness in the diagnosis of canine leishmaniasis, specifically in asymptomatic dogs, which will ensure a better evaluation of infection extent, thus improving elaboration of control programs. This PCR-HRM method is a robust and reliable tool for molecular detection and identification of Leishmania and can be easily implemented in epidemiological surveys in endemic regions.
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Reservorios de Enfermedades , Leishmania/aislamiento & purificación , Leishmaniasis/parasitología , Animales , Reservorios de Enfermedades/clasificación , Reservorios de Enfermedades/parasitología , Perros , Enfermedades Endémicas , Gerbillinae/parasitología , Erizos/parasitología , Humanos , Leishmania/genética , Leishmania/crecimiento & desarrollo , Leishmania/patogenicidad , Reacción en Cadena de la Polimerasa , Enfermedades de los Roedores/parasitología , Roedores , Temperatura de Transición , TúnezRESUMEN
Background: Livestock are key sources of livelihood among pastoral communities. Livestock productivity is chiefly constrained by pests and diseases. Due to inadequate disease surveillance in northern Kenya, little is known about pathogens circulating within livestock and the role of livestock-associated biting keds (genus Hippobosca) in disease transmission. We aimed to identify the prevalence of selected hemopathogens in livestock and their associated blood-feeding keds. Methods: We randomly collected 389 blood samples from goats (245), sheep (108), and donkeys (36), as well as 235 keds from both goats and sheep (116), donkeys (11), and dogs (108) in Laisamis, Marsabit County, northern Kenya. We screened all samples for selected hemopathogens by high-resolution melting (HRM) analysis and sequencing of PCR products amplified using primers specific to the genera: Anaplasma, Trypanosoma, Clostridium, Ehrlichia, Brucella, Theileria, and Babesia. Results: In goats, we detected Anaplasma ovis (84.5%), a novel Anaplasma sp. (11.8%), Trypanosoma vivax (7.3%), Ehrlichia canis (66.1%), and Theileria ovis (0.8%). We also detected A. ovis (93.5%), E. canis (22.2%), and T. ovis (38.9%) in sheep. In donkeys, we detected ' Candidatus Anaplasma camelii' (11.1%), T. vivax (22.2%), E. canis (25%), and Theileria equi (13.9%). In addition, keds carried the following pathogens; goat/sheep keds - T. vivax (29.3%) , Trypanosoma evansi (0.86%), Trypanosoma godfreyi (0.86%), and E. canis (51.7%); donkey keds - T. vivax (18.2%) and E. canis (63.6%); and dog keds - T. vivax (15.7%), T. evansi (0.9%), Trypanosoma simiae (0.9%) , E. canis (76%), Clostridium perfringens (46.3%), Bartonella schoenbuchensis (76%), and Brucella abortus (5.6%). Conclusions: We found that livestock and their associated ectoparasitic biting keds carry a number of infectious hemopathogens, including the zoonotic B. abortus. Dog keds harbored the most pathogens, suggesting dogs, which closely interact with livestock and humans, as key reservoirs of diseases in Laisamis. These findings can guide policy makers in disease control.
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Cynara scolymus L., known as globe artichoke, is a medicinal plant widely used in plant food supplements (PFS) and herbal infusions due to its beneficial health properties. The high demand for artichoke-containing products can lead to adulteration practices. In this work, a real-time polymerase chain reaction (PCR) system coupled to high-resolution melting (HRM) analysis was proposed to differentiate C. scolymus from other Cynara species. Hence, a Cynara-specific real-time PCR assay was successfully developed with high analytical performance, achieving a sensitivity of 0.4 pg of globe artichoke DNA. HRM analysis enabled the discrimination of C. scolymus, with a high level of confidence (>98%), corroborating sequencing data. Application results to artichoke-containing PFS and mixed herbal infusions allowed confirming the presence of C. scolymus in 38% of the samples, suggesting the substitution/mislabelling of globe artichoke in 2 samples and the need for further efforts to increase DNA amplifiability of PFS.
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Cynara scolymus , Cynara , Cynara/genética , Cynara scolymus/genéticaRESUMEN
Substituting high commercial-value meats with similar cheaper or undesirable species is a common form of food fraud that raises ethical, religious, and dietary concerns. Measures to monitor meat substitution are being put in place in many developed countries. However, information about similar efforts in sub-Saharan Africa is sparse. We used PCR coupled with high-resolution melting (PCR-HRM) analysis targeting three mitochondrial genes-cytochrome oxidase 1 (CO1), cytochrome b (cyt b), and 16S rRNA-to detect species substitution in meat sold to consumers in Nairobi, Kenya. Out of 107 meat samples representing seven livestock animals, 11 (10.3%) had been substituted, with the highest rate being observed in samples sold as goat. Our results indicate that PCR-HRM analysis is a cost- and time-effective technique that can be employed to detect species substitution. The combined use of the three mitochondrial markers produced PCR-HRM profiles that successfully allowed for the consistent distinction of species in the analysis of raw, cooked, dried, and rotten meat samples, as well as of meat admixtures. We propose that this approach has broad applications in the protection of consumers against food fraud in the meat industry in low- and middle-income countries such as Kenya, as well as in developed countries.
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OBJECTIVES: The diagnosis of malignant hyperthermia (MH) is based on clinical signs or laboratory testing. The gold standard laboratory test is the in vitro contracture test, although it is invasive, expensive, and only performed at specialized centers. Genetic diagnosis is another option, although direct mutation screening is a laborious task. Therefore, we evaluated whether high-resolution melting (HRM) curve analysis could be used as a rapid screening tool to target MH-associated mutations. MATERIALS AND METHODS: The feasibility of HRM analysis was evaluated using plasmids that were constructed by cloning wild-type or mutated versions of the ryanodine receptor 1 (RYR1) gene into the pCR2.1 plasmid. We obtained engineered plasmids and patient DNA extracted from blood samples with known wild-type or mutated sequences that are associated with MH. Amplicon lengths were kept relatively short (<250 bp) to improve discrimination between the engineered and patient plasmids. Real-time polymerase chain reaction (PCR) cycling and HRM analysis of the engineered plasmids and patient DNA were performed using the LightCycler 480 System (Roche). RESULTS: The HRM results were clearly different from those obtained using real-time PCR. Furthermore, the HRM analysis provided sufficient resolution to identify two single-nucleotide variants in the tested RYR1 exons. CONCLUSION: We conclude that HRM analysis can provide high resolution for identifying single-nucleotide variants in RYR1, which might be useful for predicting the risk of MH in the preanesthesia setting.
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Analysis of the mtDNA variation in Apis mellifera L. has allowed distinguishing subspecies and evolutionary lineages by means of different molecular methods; from RFLP, to PCR-RFLP and direct sequencing. Likewise, geometric morphometrics (GM) has been used to distinguish Africanized honey bees with a high degree of consistency with studies using molecular information. High-resolution fusion analysis (HRM) allows one to quickly identify sequence polymorphisms by comparing DNA melting curves in short amplicons generated by real-time PCR (qPCR). The objective of this work was to implement the HRM technique in the diagnosis of Africanization of colonies of A. mellifera from Argentina, using GM as a validation method. DNA was extracted from 60 A. mellifera colonies for mitotype identification. Samples were initially analyzed by HRM, through qPCRs of two regions (485 bp/385 bp) of the mitochondrial cytochrome b gene (cytb). This technique was then optimizing to amplify a smaller PCR product (207 bp) for the HRM diagnosis for the Africanization of colonies. Of the 60 colony samples analyzed, 41 were classified as colonies of European origin whereas 19 revealed African origin. All the samples classified by HRM were correctly validated by GM, demonstrating that this technique could be implemented for a rapid identification of African mitotypes in Apis mellifera samples.