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1.
Euro Surveill ; 29(26)2024 Jun.
Article in English | MEDLINE | ID: mdl-38940002

ABSTRACT

Oropouche fever is caused by Oropouche virus (OROV), transmitted primarily through the bite of infected midges, particularly of the genus Culicoides. The virus is mainly circulating in Central and South America where several countries reported an ongoing outbreak. We report here two imported cases of OROV infection identified in Italy, late May-early June 2024. These cases indicate that in the shadow of a massive dengue outbreak in the Americas, the Oropouche outbreak might be more widespread than previously estimated.


Subject(s)
Travel , Humans , Italy/epidemiology , Male , Cuba/epidemiology , Adult , Orthobunyavirus/isolation & purification , Animals , Disease Outbreaks , Bunyaviridae Infections/diagnosis , Bunyaviridae Infections/epidemiology , Middle Aged , Female
2.
Genomics ; 113(4): 1628-1638, 2021 07.
Article in English | MEDLINE | ID: mdl-33839270

ABSTRACT

Sequencing the SARS-CoV-2 genome from clinical samples can be challenging, especially in specimens with low viral titer. Here we report Accurate SARS-CoV-2 genome Reconstruction (ACoRE), an amplicon-based viral genome sequencing workflow for the complete and accurate reconstruction of SARS-CoV-2 sequences from clinical samples, including suboptimal ones that would usually be excluded even if unique and irreplaceable. The protocol was optimized to improve flexibility and the combination of technical replicates was established as the central strategy to achieve accurate analysis of low-titer/suboptimal samples. We demonstrated the utility of the approach by achieving complete genome reconstruction and the identification of false-positive variants in >170 clinical samples, thus avoiding the generation of inaccurate and/or incomplete sequences. Most importantly, ACoRE was crucial to identify the correct viral strain responsible of a relapse case, that would be otherwise mis-classified as a re-infection due to missing or incorrect variant identification by a standard workflow.


Subject(s)
COVID-19/genetics , Genome, Viral/genetics , Reinfection/genetics , SARS-CoV-2/genetics , COVID-19/pathology , COVID-19/virology , Genetic Variation/genetics , Humans , Reinfection/pathology , Reinfection/virology , SARS-CoV-2/pathogenicity , Whole Genome Sequencing
3.
BMC Bioinformatics ; 18(Suppl 5): 119, 2017 Mar 23.
Article in English | MEDLINE | ID: mdl-28361668

ABSTRACT

BACKGROUND: NGS technology represents a powerful alternative to the standard Sanger sequencing in the context of clinical setting. The proprietary software that are generally used for variant calling often depend on preset parameters that may not fit in a satisfactory manner for different genes. GATK, which is widely used in the academic world, is rich in parameters for variant calling. However the self-adjusting parameter calibration of GATK requires data from a large number of exomes. When these are not available, which is the standard condition of a diagnostic laboratory, the parameters must be set by the operator (hard filtering). The aim of the present paper was to set up a procedure to assess the best parameters to be used in the hard filtering of GATK. This was pursued by using classification trees on true and false variants from simulated sequences of a real dataset data. RESULTS: We simulated two datasets, with different coverages, including all the sequence alterations identified in a real dataset according to their observed frequencies. Simulated sequences were aligned with standard protocols and then regression trees were built up to identify the most reliable parameters and cutoff values to discriminate true and false variant calls. Moreover, we analyzed flanking sequences of region presenting a high rate of false positive calls observing that such sequences present a low complexity make up. CONCLUSIONS: Our results showed that GATK hard filtering parameter values can be tailored through a simulation study based-on the DNA region of interest to ameliorate the accuracy of the variant calling.


Subject(s)
High-Throughput Nucleotide Sequencing/methods , Mutation , Polymorphism, Genetic , Sequence Analysis, DNA/methods , Software , Computer Simulation , Exome , High-Throughput Nucleotide Sequencing/standards , Humans , Sequence Analysis, DNA/standards
4.
Blood ; 126(20): 2320-8, 2015 Nov 12.
Article in English | MEDLINE | ID: mdl-26330244

ABSTRACT

Sickle cell disease (SCD) is a worldwide distributed hereditary red cell disorder, characterized by severe organ complication. Sickle bone disease (SBD) affects a large part of the SCD patient population, and its pathogenesis has been only partially investigated. Here, we studied bone homeostasis in a humanized mouse model for SCD. Under normoxia, SCD mice display bone loss and bone impairment, with increased osteoclast and reduced osteoblast activity. Hypoxia/reperfusion (H/R) stress, mimicking acute vaso-occlusive crises (VOCs), increased bone turnover, osteoclast activity (RankL), and osteoclast recruitment (Rank) with upregulation of IL-6 as proresorptive cytokine. This was associated with further suppression of osteogenic lineage (Runx2, Sparc). To interfere with the development of SBD, zoledronic acid (Zol), a potent inhibitor of osteoclast activity/osteoclastogenesis and promoter of osteogenic lineage, was used in H/R-exposed mice. Zol markedly inhibited osteoclast activity and recruitment, promoting osteogenic lineage. The recurrent H/R stress further worsened bone structure, increased bone turnover, depressed osteoblastogenesis (Runx2, Sparc), and increased both osteoclast activity (RankL, Cathepsin k) and osteoclast recruitment (Rank) in SCD mice compared with either normoxic or single-H/R-episode SCD mice. Zol used before recurrent VOCs prevented bone impairment and promoted osteogenic lineage. Our findings support the view that SBD is related to osteoblast impairment, and increased osteoclast activity resulted from local hypoxia, oxidative stress, and the release of proresorptive cytokine such as IL-6. Zol might act on both the osteoclast and osteoblast compartments as multimodal therapy to prevent SBD.


Subject(s)
Anemia, Sickle Cell/metabolism , Bone Diseases/metabolism , Osteoclasts/metabolism , Reperfusion Injury/metabolism , Anemia, Sickle Cell/genetics , Anemia, Sickle Cell/pathology , Animals , Bone Diseases/genetics , Bone Diseases/pathology , Cathepsin K/genetics , Cathepsin K/metabolism , Core Binding Factor Alpha 1 Subunit/genetics , Core Binding Factor Alpha 1 Subunit/metabolism , Diphosphonates/pharmacology , Disease Models, Animal , Humans , Imidazoles/pharmacology , Interleukin-6/genetics , Interleukin-6/metabolism , Mice , Mice, Transgenic , Osteoclasts/pathology , Osteonectin/genetics , Osteonectin/metabolism , RANK Ligand/genetics , RANK Ligand/metabolism , Reperfusion Injury/genetics , Reperfusion Injury/pathology , Zoledronic Acid
5.
Int J Mol Sci ; 18(6)2017 Jun 13.
Article in English | MEDLINE | ID: mdl-28608802

ABSTRACT

Bisphosphonates are well known inhibitors of osteoclast activity and thus may be employed to influence osteoblast activity. The present study was designed to evaluate the in vivo effects of zoledronic acid (ZA) on the proliferation and osteoblastic commitment of mesenchymal stem cells (MSC) in osteoporotic patients. We studied 22 postmenopausal osteoporotic patients. Densitometric, biochemical, cellular and molecular data were collected before as well as after 6 and 12 months of ZA treatment. Peripheral blood MSC-like cells were quantified by colony-forming unit fibroblastic assay; their osteogenic differentiation potential was evaluated after 3 and 7 days of induction, respectively. Circulating MSCs showed significantly increased expression levels of osteoblastic marker genes such as Runt-related transcription factor 2 (RUNX2), and Osteonectin (SPARC) during the 12 months of monitoring time. Lumbar bone mineral density (BMD) variation and SPARC gene expression correlated positively. Bone turnover marker levels were significantly lowered after ZA treatment; the effect was more pronounced for C terminal telopeptide (CTX) than for Procollagen Type 1 N-Terminal Propeptide (P1NP) and bone alkaline phosphatase (bALP). Our findings suggest a discrete anabolic activity supported by osteogenic commitment of MSCs, consequent to ZA treatment. We confirm its anabolic effects in vivo on osteogenic precursors.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Diphosphonates/therapeutic use , Imidazoles/therapeutic use , Osteogenesis/drug effects , Osteoporosis, Postmenopausal/drug therapy , Aged , Bone Density Conservation Agents/pharmacology , Cell Differentiation/drug effects , Cells, Cultured , Core Binding Factor Alpha 1 Subunit/genetics , Diphosphonates/pharmacology , Female , Humans , Imidazoles/pharmacology , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/drug effects , Middle Aged , Osteonectin/genetics , Osteoporosis, Postmenopausal/genetics , Up-Regulation/drug effects , Zoledronic Acid
6.
Viruses ; 16(1)2024 01 08.
Article in English | MEDLINE | ID: mdl-38257798

ABSTRACT

Toscana virus (TOSV), a sandfly-borne virus, is an important etiological agent in human acute meningitis and meningoencephalitis in the Mediterranean area during the summer. However, the actual number of TOSV infections is underestimated. Laboratory confirmation is necessary because TOSV infection has overlapping clinical features with other neuro-invasive viral infections. Nowadays, the reference test for direct diagnosis in the acute phase of TOSV infection is the PCR based method for detecting TOSV in cerebrospinal fluid and/or plasma, serum, or blood. Although poorly employed, urine is another helpful biological matrix for TOSV detection. Urine is a matrix rich in PCR inhibitors that affect PCR efficiency; consequently, false negatives could be generated. To investigate the potential effect of urine PCR inhibitors on TOSV detection, we compared undiluted and diluted urine using 10-fold series of spiked TOSV. The results showed a significant improvement in TOSV detection performance in diluted urine (1 TCID50 vs. 1 × 104 TCID50 limit of detection and 101.35% vs. 129.62% efficiency, respectively, in diluted and undiluted urine). In conclusion, our data provide preliminary important insights into the use of diluted urine to limit the impact of the inhibitory effects of urine on the detection of TOSV in RT-PCR-based approaches.


Subject(s)
Body Fluids , Encephalitis, California , Sandfly fever Naples virus , Humans , Sandfly fever Naples virus/genetics , Plasma , Laboratories
7.
Viruses ; 16(5)2024 05 03.
Article in English | MEDLINE | ID: mdl-38793608

ABSTRACT

In 2022, an unprecedented outbreak of mpox raged in several nations. Sequences from the 2022 outbreak reveal a higher nucleotide substitution if compared with the estimated rate for orthopoxviruses. Recently, intra-lesion SNVs (single nucleotide variants) have been described, and these have been suggested as possible sources of genetic variation. Until now, it has not been clear if the presence of several SNVs could represents the result of local mutagenesis or a possible co-infection. We investigated the significance of SNVs through whole-genome sequencing analysis of four unrelated mpox cases. In addition to the known mutations harboured by the circulating strains of virus (MPXV), 7 novel mutations were identified, including SNVs located in genes that are involved in immune evasion mechanisms and/or viral fitness, six of these appeared to be APOBEC3-driven. Interestingly, three patients exhibited the coexistence of mutated and wild-type alleles for five non-synonymous variants. In addition, two patients, apparently unrelated, showed an analogous pattern for two novel mutations, albeit with divergent frequencies. The coexistence of mixed viral populations, harbouring non-synonymous mutations in patients, supports the hypothesis of possible co-infection. Additional investigations of larger clinical cohorts are essential to validating intra-patient viral genome heterogeneity and determining the possibility of co-presence events of slightly divergent MPXV strains.


Subject(s)
Disease Outbreaks , Genome, Viral , Mutation , Whole Genome Sequencing , Humans , Italy/epidemiology , Male , Orthopoxvirus/genetics , Orthopoxvirus/classification , Poxviridae Infections/virology , Poxviridae Infections/epidemiology , Poxviridae Infections/veterinary , Female , Coinfection/virology , Coinfection/epidemiology , Phylogeny , Polymorphism, Single Nucleotide , Middle Aged , Genetic Variation
8.
Viruses ; 16(5)2024 04 23.
Article in English | MEDLINE | ID: mdl-38793539

ABSTRACT

With the continuous spread of new SARS-CoV-2 variants of concern (VOCs), the monitoring of diagnostic test performances is mandatory. We evaluated the changes in antigen diagnostic tests' (ADTs) accuracy along the Delta to Omicron VOCs transition, exploring the N protein mutations possibly affecting ADT sensitivity and assessing the best sampling site for the diagnosis of Omicron infections. In total, 5175 subjects were enrolled from 1 October 2021 to 15 July 2022. The inclusion criteria were SARS-CoV-2 ADT combined with a same-day RT-PCR swab test. For the sampling site analysis, 61 patients were prospectively recruited during the Omicron period for nasal and oral swab analyses by RT-PCR. Next-Generation Sequencing data were obtained to evaluate the different sublineages. Using RT-PCR as a reference, 387 subjects resulted in becoming infected and the overall sensitivity of the ADT decreased from 63% in the Delta period to 33% in the Omicron period. This decrease was highly statistically significant (p < 0.001), and no decrease in viral load was detected at the RNA level. The nasal site presented a significantly higher viral load than the oral site during the Omicron wave. The reduced detection rate of Omicron infections by ADT should be considered in the global testing strategy to preserve accurate diagnoses across the changing SARS-CoV-2 variants.


Subject(s)
COVID-19 , SARS-CoV-2 , Sensitivity and Specificity , Humans , SARS-CoV-2/immunology , SARS-CoV-2/genetics , COVID-19/diagnosis , COVID-19/virology , COVID-19/immunology , Male , Viral Load , Female , Antigens, Viral/immunology , COVID-19 Serological Testing/methods , Mutation , Middle Aged , Adult , Prospective Studies , RNA, Viral/genetics , Aged
9.
Asp Mol Med ; 1: 100008, 2023.
Article in English | MEDLINE | ID: mdl-37519862

ABSTRACT

Like for other coronaviruses, SARS-CoV-2 gene expression strategy is based on the synthesis of a nested set of subgenomic mRNA species (sgRNAs). These sgRNA are synthesized using a "discontinuous transcription" mechanism that relies on template switching at Transcription Regulatory Sequences (TRS). Both canonical (c-sgRNA) and non-canonical (nc-sgRNA, less numerous) subgenomic RNA species can be produced. Currently, sgRNAs are investigated on the basis of sequence data obtained through next generation sequencing (NGS), and bioinformatic tools are crucial for their identification, characterization and quantification. To date, few software have been developed to this aim, whose reliability and applicability to all the available NGS platforms need to be established, to build confidence on the information resulting from such tools. In fact, these information may be crucial for the in depth elucidation of viral expression strategy, particularly in respect of the significance of nc-sgRNAs, and for the possible use of sgRNAs as potential markers of virus replicative activity in infected patients.

10.
Diagnostics (Basel) ; 13(7)2023 Apr 04.
Article in English | MEDLINE | ID: mdl-37046567

ABSTRACT

BACKGROUND: Monkeypox virus (MPXV) is a double-stranded DNA virus belonging to the orthopoxvirus genus in the family Poxviridae. Distinct clades are identified: the clade I belonging to the Central African (or Congo Basin) clade and the subclades IIa and IIb belonging to the West African clade. Here, a commercial droplet digital PCR (ddPCR) assay was evaluated for the quantification of the MPXV West Africa clade in clinical samples. METHODS: The ddPCR reaction was assessed as a duplex assay using RPP30 as an internal amplification control. A total of 60 clinical specimens were tested, 40 positives (skin lesions, n=10; rectal swabs, n = 10; pharyngeal swabs, n = 10; and whole blood, n = 10), and 20 negatives (n = 5 for each biological matrix) were found at the routine molecular diagnostics (orthopoxvirus qPCR followed by confirmation with Sanger sequencing). To evaluate the analytical sensitivity, the ddPCR reaction was first analyzed on serial dilutions of synthetic DNA spiked in water and in negative biological matrices, achieving a limit of detection of 3.5 copy/µL. RESULTS: Regarding the clinical samples, compared to routine molecular diagnostics, the ddPCR duplex assay showed 100% of specificity for all biological matrices and 100% sensitivity (10/10) for lesions, 100% (10/10) for rectal swabs, 90% (9/10) for pharyngeal swabs, and 60% (6/10) for whole blood. CONCLUSION: Overall, our data showed that the commercial ddPCR assay allowed the DNA detection of MPXV in 87.5% (35/40) of our cohort, highlighting useful technical indications for the different specimens with a potential greatest performance for skin lesions and rectal swabs.

11.
Pathogens ; 12(2)2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36839437

ABSTRACT

Coupled with its rarity in non-endemic areas, the clinical heterogeneity of leprosy makes diagnosis very challenging. We report a diagnosis of multibacillary leprosy in a 22-year-old Indian woman, adopted at the age of 10 and living in Italy. The patient presented with painful skin lesions on the face, trunk, and lower and upper extremities, associated with dysesthesia and a motor deficit in her left leg following corticosteroid therapy interruption. Histopathology results from the skin lesions suggested leprosy, but no acid-fast bacilli were identified. Molecular biology in a center specializing in tropical diseases confirmed the diagnosis, allowing prompt and adequate treatment. Genotype analysis allowed the identification of a genotype 1D of M. leprae, facilitating the epidemiological investigation of the plausible infection origin. No resistances to rifampicin, dapsone, or ofloxacin were detected. Leprosy will continue to exist in high-income nations, and the incidence may rise over time due to increasing migration and globalization. CARE guidelines were followed.

12.
Life Sci Alliance ; 6(12)2023 12.
Article in English | MEDLINE | ID: mdl-37748810

ABSTRACT

During the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), positive-sense genomic RNA and subgenomic RNAs (sgRNAs) are synthesized by a discontinuous process of transcription characterized by a template switch, regulated by transcription-regulating sequences (TRS). Although poorly known about makeup and dynamics of sgRNAs population and function of its constituents, next-generation sequencing approaches with the help of bioinformatics tools have made a significant contribution to expand the knowledge of sgRNAs in SARS-CoV-2. For this scope to date, Periscope, LeTRS, sgDI-tector, and CORONATATOR have been developed. However, limited number of studies are available to compare the performance of such tools. To this purpose, we compared Periscope, LeTRS, and sgDI-tector in the identification of canonical (c-) and noncanonical (nc-) sgRNA species in the data obtained with the Illumina ARTIC sequencing protocol applied to SARS-CoV-2-infected Caco-2 cells, sampled at different time points. The three software showed a high concordance rate in the identification and in the quantification of c-sgRNA, whereas more differences were observed in nc-sgRNA. Overall, LeTRS and sgDI-tector result to be adequate alternatives to Periscope to analyze Fastq data from sequencing platforms other than Nanopore.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , Subgenomic RNA , Caco-2 Cells , Computational Biology , RNA
13.
BMC Bioinformatics ; 13 Suppl 14: S7, 2012.
Article in English | MEDLINE | ID: mdl-23095502

ABSTRACT

BACKGROUND: Imputation is a statistical process used to predict genotypes of loci not directly assayed in a sample of individuals. Our goal is to measure the performance of imputation in predicting the genotype of the best known gene polymorphisms involved in drug metabolism using a common SNP array genotyping platform generally exploited in genome wide association studies. METHODS: Thirty-nine (39) individuals were genotyped with both Affymetrix Genome Wide Human SNP 6.0 (AFFY) and Affymetrix DMET Plus (DMET) platforms. AFFY and DMET contain nearly 900000 and 1931 markers respectively. We used a 1000 Genomes Pilot + HapMap 3 reference panel. Imputation was performed using the computer program Impute, version 2. SNPs contained in DMET, but not imputed, were analysed studying markers around their chromosome regions. The efficacy of the imputation was measured evaluating the number of successfully imputed SNPs (SSNPs). RESULTS: The imputation predicted the genotypes of 654 SNPs not present in the AFFY array, but contained in the DMET array. Approximately 1000 SNPs were not annotated in the reference panel and therefore they could not be directly imputed. After testing three different imputed genotype calling threshold (IGCT), we observed that imputation performs at its best for IGCT value equal to 50%, with rate of SSNPs (MAF > 0.05) equal to 85%. CONCLUSIONS: Most of the genes involved in drug metabolism can be imputed with high efficacy using standard genome-wide genotyping platforms and imputing procedures.


Subject(s)
Genome-Wide Association Study , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Pharmacogenetics/methods , Polymorphism, Single Nucleotide , Statistics as Topic/methods , Economics, Pharmaceutical , Genetic Markers , Genome, Human , HapMap Project , Humans , Reproducibility of Results , Software
14.
Front Cell Infect Microbiol ; 12: 1005955, 2022.
Article in English | MEDLINE | ID: mdl-36204640

ABSTRACT

Starting from mid-May 2022, cases of human monkeypox started to rise in several non-endemic countries. By mid-July, more than 17000 confirmed/suspect cases have been reported by at least 82 countries worldwide, with a regular incremental trend. In order to contain the disease diffusion, risk evaluation is crucial to undertake informed decisions and effective communication campaigns. However, since orthopoxvirus infections so far have attracted low attention, due to the eradication of smallpox 40 years ago, and to the confinement of human monkeypox almost exclusively to endemic areas, several unresolved issues concerning natural history, ecology and pathogenesis remain. To this respect, we identified some open questions and reviewed the relevant literature on monkeypoxvirus and/or related orthopoxviruses. The results will be discussed in the perspective of their relevance to public health decisions, particularly those related to non-pharmacological interventions.


Subject(s)
Mpox (monkeypox) , Smallpox , Disease Outbreaks , Humans , Mpox (monkeypox)/epidemiology , Monkeypox virus/genetics , Public Health
15.
Sci Rep ; 12(1): 9957, 2022 06 15.
Article in English | MEDLINE | ID: mdl-35705621

ABSTRACT

Strongyloidiasis is a neglected tropical disease caused by the soil-transmitted nematode by Strongyloides stercoralis, that affects approximately 600 million people worldwide. In immunosuppressed individuals disseminated strongyloidiasis can rapidly lead to fatal outcomes. There is no gold standard for diagnosing strongyloidiasis, and infections are frequently misdiagnosed. A better understanding of the molecular biology of this parasite can be useful for example for the discovery of potential new biomarkers. Interestingly, recent evidence showed the presence of small RNAs in Strongyloididae, but no data was provided for S. stercoralis. In this study, we present the first identification of miRNAs of both L1 and iL3 larval stages of S. stercoralis. For our purpose, the aims were: (i) to analyse the miRNome of L1 and iL3 S. stercoralis and to identify potential miRNAs of this nematode, (ii) to obtain the mRNAs profiles in these two larval stages and (iii) to predict potential miRNA target sites in mRNA sequences. Total RNA was isolated from L1 and iL3 collected from the stool of 5 infected individuals. For the miRNAs analysis, we used miRDeep2 software and a pipeline of bio-informatic tools to construct a catalog of a total of 385 sequences. Among these, 53% were common to S. ratti, 19% to S. papillosus, 1% to Caenorhabditis elegans and 44% were novel. Using a differential analysis between the larval stages, we observed 6 suggestive modulated miRNAs (STR-MIR-34A-3P, STR-MIR-8397-3P, STR-MIR-34B-3P and STR-MIR-34C-3P expressed more in iL3, and STR-MIR-7880H-5P and STR-MIR-7880M-5P expressed more in L1). Along with this analysis, we obtained also the mRNAs profiles in the same samples of larvae. Multiple testing found 81 statistically significant mRNAs of the total 1553 obtained (FDR < 0.05; 32 genes expressed more in L1 than iL3; 49 genes expressed more in L3 than iL1). Finally, we found 33 predicted mRNA targets of the modulated miRNAs, providing relevant data for a further validation to better understand the role of these small molecules in the larval stages and their valuein clinical diagnostics.


Subject(s)
MicroRNAs , Strongyloides stercoralis , Strongyloidiasis , Animals , Feces/parasitology , Humans , Larva/genetics , MicroRNAs/genetics , RNA, Messenger , Strongyloides stercoralis/genetics , Strongyloidiasis/diagnosis , Strongyloidiasis/genetics , Strongyloidiasis/parasitology
16.
Acta Trop ; 219: 105893, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33872586

ABSTRACT

Over 90% of schistosomiasis infections occur in sub-Saharan Africa. A rapid ICT test would be a cheap and easy tool that could be used also in the field. We preliminarily evaluated the performance of a new Schistosoma black-latex based IgG-IgM ICT (Black-ICT) on serum samples. The results indicate a high sensitivity (98.0%) but the specificity depends on the application of a cut-off value that can discriminate between positive and negative samples. Considering a possible direct application of this test on blood from finger prick, the results are promising, providied that a signal intensity scale is developed, guiding the result interpretation.


Subject(s)
Immunologic Tests/methods , Schistosoma/isolation & purification , Animals , Antibodies, Helminth/blood , Humans , Immunoglobulin G/blood , Schistosoma/immunology , Sensitivity and Specificity
17.
Expert Rev Mol Diagn ; 21(6): 591-612, 2021 06.
Article in English | MEDLINE | ID: mdl-33910444

ABSTRACT

Introduction: Molecular technology has played an important role in arboviruses diagnostics. PCR-based methods stand out in terms of sensitivity, specificity, cost, robustness, and accessibility, and especially the isothermal amplification (IA) method is ideal for field-adaptable diagnostics in resource-limited settings (RLS).Areas covered: In this review, we provide an overview of the various molecular methods for West Nile, Zika, Dengue and Chikungunya. We summarize literature works reporting the assessment and use of in house and commercial assays. We describe limitations and challenges in the usage of methods and opportunities for novel approaches such as NNext-GenerationSequencing (NGS).Expert opinion: The rapidity and accuracy of differential diagnosis is essential for a successful clinical management, particularly in co-circulation area of arboviruses. Several commercial diagnostic molecular assays are available, but many are not affordable by RLS and not usable as Point-of-care/Point-of-need (POC/PON) such as RReal-TimeRT-PCR, Array-based methods and NGS. In contrast, the IA-based system fits better for POC/PON but it is still not ideal for the multiplexing detection system. Improvement in the characterization and validation of current molecular assays is needed to optimize their translation to the point of care.


Subject(s)
Arboviruses , Chikungunya Fever , Dengue , Zika Virus Infection , Zika Virus , Arboviruses/genetics , Chikungunya Fever/diagnosis , Dengue/diagnosis , Genomics , Humans , RNA, Viral/genetics , Zika Virus/genetics , Zika Virus Infection/diagnosis
18.
Microorganisms ; 9(8)2021 Aug 14.
Article in English | MEDLINE | ID: mdl-34442817

ABSTRACT

SARS-CoV-2 infection was monitored in 1898 health care workers (HCWs) after receiving full vaccination with BNT162b2. Untill 30 June 2021, 10 HCWs tested positive for SARS-CoV-2 using real time RT-PCR, resulting in a 4-month cumulative incidence of 0.005%. The infection was mildly symptomatic in six (60%) and asymptomatic in four (40%) individuals. Among the infected HCWs, eight consenting individuals provided paired NPS and saliva during the course of infection, for the purpose of the analysis performed in the present study. Genomic and subgenomic viral RNAs were investigated using real-time RT-PCR in both biological specimens. The temporal profile of viral load was measured using ddPCR. Viral mutations were also analysed. Subgenomic viral RNA was detected in 8/8 (100%) NPS and in 6/8 (75%) saliva specimens at the baseline. The expression of subgenomic RNA was observed for up to 7 days in 3/8 (38%) symptomatic cases. Moreover, concordance was observed between NPS and saliva in the detection of viral mutations, and both N501Y and 69/70del (associated with the B.1.1.7 variant) were detected in the majority 6/8 (75%) of subjects, while the K417T mutation (associated with the P.1-type variants) was detected in 2/8 (25%) individuals. Overall, our findings report a low frequency of infected HCWs after full vaccination. It is, therefore, important to monitor the vaccinees in order to identify asymptomatic infected individuals. Saliva can be a surrogate for SARS-CoV-2 surveillance, particularly in social settings such as hospitals.

19.
Sci Rep ; 11(1): 14922, 2021 07 21.
Article in English | MEDLINE | ID: mdl-34290274

ABSTRACT

The GNA15 gene is ectopically expressed in human pancreatic ductal adenocarcinoma cancer cells. The encoded Gα15 protein can promiscuously redirect GPCR signaling toward pathways with oncogenic potential. We sought to describe the distribution of GNA15 in adenocarcinoma from human pancreatic specimens and to analyze the mechanism driving abnormal expression and the consequences on signaling and clinical follow-up. We detected GNA15 expression in pre-neoplastic pancreatic lesions and throughout progression. The analysis of biological data sets, primary and xenografted human tumor samples, and clinical follow-up shows that elevated expression is associated with poor prognosis for GNA15, but not any other GNA gene. Demethylation of the 5' GNA15 promoter region was associated with ectopic expression of Gα15 in pancreatic neoplastic cells, but not in adjacent dysplastic or non-transformed tissue. Down-modulation of Gα15 by shRNA or CRISPR/Cas9 affected oncogenic signaling, and reduced adenocarcimoma cell motility and invasiveness. We conclude that de novo expression of wild-type GNA15 characterizes transformed pancreatic cells. The methylation pattern of GNA15 changes in preneoplastic lesions coincident with the release a transcriptional blockade that allows ectopic expression to persist throughout PDAC progression. Elevated GNA15 mRNA correlates with poor prognosis. In addition, ectopic Gα15 signaling provides an unprecedented mechanism in the early steps of pancreas carcinogenesis distinct from classical G protein oncogenic mutations described previously in GNAS and GNAQ/GNA11.


Subject(s)
Carcinoma, Pancreatic Ductal/genetics , GTP-Binding Protein alpha Subunits, Gq-G11/genetics , Gene Expression Regulation, Neoplastic/genetics , Pancreatic Neoplasms/genetics , CRISPR-Cas Systems , Carcinoma, Pancreatic Ductal/pathology , Cell Line, Tumor , Cell Movement/genetics , GTP-Binding Proteins/metabolism , Gene Expression/genetics , Humans , Methylation , Neoplasm Invasiveness/genetics , Pancreatic Neoplasms/pathology , Prognosis , Promoter Regions, Genetic/genetics , RNA, Messenger , RNA, Small Interfering , Signal Transduction
20.
Sci Rep ; 10(1): 18764, 2020 10 30.
Article in English | MEDLINE | ID: mdl-33127953

ABSTRACT

Droplet digital PCR (ddPCR) is a sensitive and reproducible technology widely used for quantitation of several viruses. The aim of this study was to evaluate the 2019-nCoV CDC ddPCR Triplex Probe Assay (BioRad) performance, comparing the direct quantitation of SARS-CoV-2 on nasopharyngeal swab with the procedure applied to the extracted RNA. Moreover, two widely used swab types were compared (UTM 3 mL and ESwab 1 mL, COPAN). A total of 50 nasopharyngeal swabs (n = 25 UTM 3 mL and n = 25 ESwab 1 mL) from SARS-CoV-2 patients, collected during the pandemic at IRCCS Sacro Cuore Don Calabria Hospital (Veneto Region, North-East Italy), were used for our purpose. After heat inactivation, an aliquot of swab medium was used for the direct quantitation. Then, we compared the direct method with the quantitation performed on the RNA purified from nasopharyngeal swab by automated extraction. We observed that the direct approach achieved generally equal RNA copies compared to the extracted RNA. The results with the direct quantitation were more accurate on ESwab with a sensitivity of 93.33% [95% CI, 68.05 to 99.83] and specificity of 100.00% for both N1 and N2. On the other hand, on UTM we observed a higher rate of discordant results for N1 and N2. The human internal amplification control (RPP30) showed 100% of both sensitivity and specificity independent of swabs and approaches. In conclusion, we described a direct quantitation of SARS-CoV-2 in nasopharyngeal swab. Our approach resulted in an efficient quantitation, without automated RNA extraction and purification. However, special care needs to be taken on the potential bias due to the conservation of samples and to the heating treatment, as we used thawed and heat inactivated material. Further studies on a larger cohort of samples are warranted to evaluate the clinical value of this direct approach.


Subject(s)
Clinical Laboratory Techniques/methods , Multiplex Polymerase Chain Reaction/methods , Betacoronavirus/genetics , Betacoronavirus/pathogenicity , COVID-19 Testing , Clinical Laboratory Techniques/standards , Coronavirus Infections/diagnosis , Humans , Limit of Detection , Multiplex Polymerase Chain Reaction/standards , Reproducibility of Results , Respiratory Mucosa/virology , SARS-CoV-2
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