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Indian Journal of Public Health Oct 2023LAMP assay is widely used for detecting pathogens. We observed that the conventional and gradient polymerase chain reaction (PCR) could not detect the extracted...
Electrophoresis of Amplicons is a Better Method to Understand the Performance of Loop-mediated Isothermal Amplification Assay for Screening the Presence of Escherichia coli in Water.
LAMP assay is widely used for detecting pathogens. We observed that the conventional and gradient polymerase chain reaction (PCR) could not detect the extracted Escherichia coli DNA; real-time PCR was able to detect up to a certain limit (10-8 bacterial dilution). At the same time, the LAMP assay could detect the bacteria at a much lower concentration (10-14 dilution). The results of the LAMP assay were evaluated using agarose gel electrophoresis and DNA binding dye (PicoGreen), but only gel electrophoresis gave reliable results. Therefore, we propose using electrophoresis-based amplicon detection to overcome the limitations of dye-based detection. We believe that this amplicon detection will go a long way in the screening of potable drinking water.
Topics: Escherichia coli; Nucleic Acid Amplification Techniques; Water Microbiology; Real-Time Polymerase Chain Reaction; Humans; Electrophoresis, Agar Gel; DNA, Bacterial; Molecular Diagnostic Techniques; Drinking Water
PubMed: 38934812
DOI: 10.4103/ijph.ijph_1628_22 -
Infection and Drug Resistance 2024To analyze the antibiotic resistance profile, virulence genes, and molecular typing of () strains isolated in skin and soft tissue infections at the First Affiliated...
OBJECTIVE
To analyze the antibiotic resistance profile, virulence genes, and molecular typing of () strains isolated in skin and soft tissue infections at the First Affiliated Hospital, Gannan Medical University, to better understand the molecular epidemiological characteristics of .
METHODS
In 2023, 65 strains were isolated from patients with skin and soft tissue infections. Strain identification and susceptibility tests were performed using VITEK 2 and gram-positive bacteria identification cards. DNA was extracted using a DNA extraction kit, and all genes were amplified using polymerase chain reaction. Multilocus sequence typing (MLST) was used for molecular typing.
RESULTS
In this study, of the 65 strains were tested for their susceptibility to 16 antibiotics, the highest resistance rate to penicillin G was 95.4%. None of the staphylococcal isolates showed resistance to ceftaroline, daptomycin, linezolid, tigecycline, teicoplanin, or vancomycin. was the most prevalent virulence gene (100%) in strains isolated in skin and soft tissue infections, followed by (98.5%). Statistical analyses showed that the resistance rates of methicillin-resistant isolates to various antibiotics were significantly higher than those of methicillin-susceptible isolates. Fifty sequence types (STs), including 44 new ones, were identified by MLST.
CONCLUSION
In this study, the high resistance rate to penicillin G and the high carrying rate of virulence gene and of S.aureus were determine, and 44 new STs were identified, which may be associated with the geographical location of southern Jiangxi and local trends in antibiotic use. The study of the clonal lineage and evolutionary relationships of in these regions may help in understanding the molecular epidemiology and provide the experimental basis for pathogenic bacteria prevention and treatment.
PubMed: 38933775
DOI: 10.2147/IDR.S465951 -
Frontiers in Plant Science 2024Stripe rust, caused by f. sp. (), is a serious disease that affects wheat worldwide. There is a great need to develop cultivars with combinations of all-stage...
Stripe rust, caused by f. sp. (), is a serious disease that affects wheat worldwide. There is a great need to develop cultivars with combinations of all-stage resistance (ASR) and adult-plant resistance (APR) genes for sustainable control of the disease. in the Italian durum wheat ( ssp. ) cultivar Svevo is effective against races in China and Israel, and the gene has been previously mapped to the long arm of chromosome 1B. The gene is flanked by SNP (single nucleotide polymorphism) markers and (0.75 cM). In the present study, we used high-density 660K SNP array genotyping and the phenotypes of 137 recombinant inbred lines (RILs) to fine map the locus within a 1.066 Mb region in durum wheat Svevo (RefSeq Rel. 1.0) on chromosome arm 1BL. The identified 1.066 Mb region overlaps with a previously described map of , a stripe rust APR gene. Twenty-five candidate genes for were identified through comparing polymorphic genes within the 1.066 Mb region in the resistant cultivar. SNP markers were selected and converted to Kompetitive allele-specific polymerase chain reaction (KASP) markers. Five KASP markers based on SNP were validated in a F and F breeding population, providing further compelling evidence for the significant effects of . These markers should be useful in marker-assisted selection for incorporating into new durum and common wheat cultivars for resistance to stripe rust.
PubMed: 38933466
DOI: 10.3389/fpls.2024.1395223 -
Frontiers in Immunology 2024This study seeks to enhance the accuracy and efficiency of clinical diagnosis and therapeutic decision-making in hepatocellular carcinoma (HCC), as well as to optimize...
BACKGROUND
This study seeks to enhance the accuracy and efficiency of clinical diagnosis and therapeutic decision-making in hepatocellular carcinoma (HCC), as well as to optimize the assessment of immunotherapy response.
METHODS
A training set comprising 305 HCC cases was obtained from The Cancer Genome Atlas (TCGA) database. Initially, a screening process was undertaken to identify prognostically significant immune-related genes (IRGs), followed by the application of logistic regression and least absolute shrinkage and selection operator (LASSO) regression methods for gene modeling. Subsequently, the final model was constructed using support vector machines-recursive feature elimination (SVM-RFE). Following model evaluation, quantitative polymerase chain reaction (qPCR) was employed to examine the gene expression profiles in tissue samples obtained from our cohort of 54 patients with HCC and an independent cohort of 231 patients, and the prognostic relevance of the model was substantiated. Thereafter, the association of the model with the immune responses was examined, and its predictive value regarding the efficacy of immunotherapy was corroborated through studies involving three cohorts undergoing immunotherapy. Finally, the study uncovered the potential mechanism by which the model contributed to prognosticating HCC outcomes and assessing immunotherapy effectiveness.
RESULTS
SVM-RFE modeling was applied to develop an OS prognostic model based on six IRGs (CMTM7, HDAC1, HRAS, PSMD1, RAET1E, and TXLNA). The performance of the model was assessed by AUC values on the ROC curves, resulting in values of 0.83, 0.73, and 0.75 for the predictions at 1, 3, and 5 years, respectively. A marked difference in OS outcomes was noted when comparing the high-risk group (HRG) with the low-risk group (LRG), as demonstrated in both the initial training set (0.0001) and the subsequent validation cohort (0.0001). Additionally, the SVMRS in the HRG demonstrated a notable positive correlation with key immune checkpoint genes (CTLA-4, PD-1, and PD-L1). The results obtained from the examination of three cohorts undergoing immunotherapy affirmed the potential capability of this model in predicting immunotherapy effectiveness.
CONCLUSIONS
The HCC predictive model developed in this study, comprising six genes, demonstrates a robust capability to predict the OS of patients with HCC and immunotherapy effectiveness in tumor management.
Topics: Humans; Carcinoma, Hepatocellular; Liver Neoplasms; Immunotherapy; Prognosis; Biomarkers, Tumor; Male; Female; Transcriptome; Middle Aged; Gene Expression Regulation, Neoplastic; Gene Expression Profiling; Support Vector Machine; Treatment Outcome
PubMed: 38933262
DOI: 10.3389/fimmu.2024.1371829 -
Frontiers in Cellular Neuroscience 2024Human cerebral organoids (hCOs) derived from pluripotent stem cells are very promising for the study of neurodevelopment and the investigation of the healthy or diseased...
INTRODUCTION
Human cerebral organoids (hCOs) derived from pluripotent stem cells are very promising for the study of neurodevelopment and the investigation of the healthy or diseased brain. To help establish hCOs as a powerful research model, it is essential to perform the morphological characterization of their cellular components in depth.
METHODS
In this study, we analyzed the cell types consisting of hCOs after culturing for 45 days using immunofluorescence and reverse transcriptase qualitative polymerase chain reaction (RT-qPCR) assays. We also analyzed their subcellular morphological characteristics by transmission electron microscopy (TEM).
RESULTS
Our results show the development of proliferative zones to be remarkably similar to those found in human brain development with cells having a polarized structure surrounding a central cavity with tight junctions and cilia. In addition, we describe the presence of immature and mature migrating neurons, astrocytes, oligodendrocyte precursor cells, and microglia-like cells.
DISCUSSION
The ultrastructural characterization presented in this study provides valuable information on the structural development and morphology of the hCO, and this information is of general interest for future research on the mechanisms that alter the cell structure or function of hCOs.
PubMed: 38933177
DOI: 10.3389/fncel.2024.1406839 -
Frontiers in Public Health 2024The end of the coronavirus disease 2019 (COVID-19) pandemic has been declared by the World Health Organization on May 5, 2023. Several vaccines were developed, and new...
The impact of comorbidity status in COVID-19 vaccines effectiveness before and after SARS-CoV-2 omicron variant in northeastern Mexico: a retrospective multi-hospital study.
INTRODUCTION
The end of the coronavirus disease 2019 (COVID-19) pandemic has been declared by the World Health Organization on May 5, 2023. Several vaccines were developed, and new data is being published about their effectiveness. However, the clinical trials for the vaccines were performed before the Omicron variant appeared and there are population groups where vaccine effectiveness still needs to be tested. The overarching goal of the present study was to analyze the effects of COVID-19 vaccination before and after the Omicron variant in patients considering comorbidities in a population from Nuevo Leon, Mexico.
METHODS
Epidemiological COVID-19 data from the Mexican Social Security Institute were collected from 67 hospitals located in northeastern Mexico, from July 2020 to May 2023, and a total of 669,393 cases were compiled, 255,819 reported a SARS-CoV-2 positive reverse transcription quantitative polymerase chain reaction (RT-qPCR) test or a positive COVID-19 antigen rapid test.
RESULTS
Before Omicron (BO, 2020-2021), after 14 days of two doses of COVID-19 vaccine, BNT162b2 and ChAdOx1 vaccines were effective against infection in non-comorbid and all comorbid subgroups, whereas after Omicron (AO, 2022- 2023) there was no significant effectiveness against infection with none of the vaccines. Regarding hospitalization BO, BNT162b2, ChAdOx1, CoronaVac and mRNA-1273 significantly protected non-comorbid patients whereas BNT162b2, ChAdOx1, and mRNA-1273, protected all comorbid subgroups against hospitalization. AO, BNT162b2, ChAdOx1, CoronaVac and mRNA-1273 were effective against hospitalization in non-comorbid patients whereas for most comorbid subgroups BNT162b2, ChAdOx1 and CoronaVac were effective against hospitalization. Non-comorbid patients were protected against death as an outcome of COVID-19 during the BO period with most vaccines whereas a reduction in effectiveness was observed AO with mRNA-1273 vaccines in patients with hypertension, and diabetes mellitus.
DISCUSSION
BO, COVID-19 vaccines were effective against infection, hospitalization, and death whereas AO, COVID-19 vaccines failed to protect the population from COVID-19 infection. A varying effectiveness against hospitalization and death is observed AO.
Topics: Humans; COVID-19; Mexico; COVID-19 Vaccines; Comorbidity; Middle Aged; Female; Male; Vaccine Efficacy; Retrospective Studies; SARS-CoV-2; Adult; Aged; Adolescent; Young Adult
PubMed: 38932780
DOI: 10.3389/fpubh.2024.1402527 -
Journal of Diabetes Investigation Jun 2024We investigated the relationship of circulating TSP-1 mRNA and miR-194 with diabetic kidney disease's degree.
Relationship between circulating thrombospondin-1 messenger ribonucleic acid and microribonucleic acid-194 levels in Chinese patients with type 2 diabetic kidney disease: The outcomes of a case-control study.
AIMS/INTRODUCTION
We investigated the relationship of circulating TSP-1 mRNA and miR-194 with diabetic kidney disease's degree.
MATERIALS AND METHODS
We enrolled 167 hospitalized type 2 diabetes patients in the endocrinology department. Patients were split into three groups according to urinary microalbumin: A, B and C. The control group comprised healthy outpatients (n = 163). The quantities of microribonucleic acid (miR)-194 and thrombospondin-1 (TSP-1) messenger ribonucleic acid (mRNA) in the participants' circulation were measured using a quantitative real-time polymerase chain reaction.
RESULTS
Circulating TSP-1 mRNA (P = 0.024) and miR-194 (P = 0.029) expressions significantly increased in type 2 diabetes patients. Circulating TSP-1 mRNA (P = 0.040) and miR-194 (P = 0.007) expression levels differed significantly among the three groups; circulating TSP-1 mRNA expression increased with urinary microalbumin. However, miR-194 declined in group B and increased in group C. Circulating TSP-1 mRNA was positively correlated with cystatin-c (r = 0.281; P = 0.021) and microalbumin/creatinine ratio (UmALB/Cr; r = 0.317; P = 0.009); miR-194 was positively correlated with UmALB/Cr (r = 0.405; P = 0.003). Stepwise multivariate linear regression analysis showed cystatin-c (β = 0.578; P = 0.021) and UmALB/Cr (β = 0.001; P = 0.009) as independent factors for TSP-1 mRNA; UmALB/Cr (β = 0.005; P = 0.028) as an independent factor for miR194. Areas under the curve for circulating TSP-1 mRNA and miR194 were 0.756 (95% confidence interval 0.620-0.893; sensitivity 0.69 and specificity 0.71, P < 0.01) and 0.584 (95% confidence interval 0.421-0.748; sensitivity 0.54 and specificity 0.52, P < 0.01), respectively.
CONCLUSIONS
Circulating TSP-1 mRNA and miR-194 expressions significantly increased in type 2 diabetes patients. The microalbumin group had lower levels of miR-194 (a risk factor that is valuable for type 2 diabetes kidney disease evaluation).
PubMed: 38932465
DOI: 10.1111/jdi.14252 -
Viruses Jun 2024Quantification of Torquetenovirus (TTV) viremia is becoming important for evaluating the status of the immune system in solid organ transplant recipients, monitoring the...
Quantification of Torquetenovirus (TTV) viremia is becoming important for evaluating the status of the immune system in solid organ transplant recipients, monitoring the appearance of post-transplant complications, and controlling the efficacy of maintenance immunosuppressive therapy. Thus, diagnostic approaches able to scale up TTV quantification are needed. Here, we report on the development and validation of a real-time PCR assay for TTV quantification on the Hologic Panther Fusion System by utilizing its open-access channel. The manual real-time PCR previously developed in our laboratories was optimized to detect TTV DNA on the Hologic Panther Fusion System. The assay was validated using clinical samples. The automated TTV assay has a limit of detection of 1.6 log copies per ml of serum. Using 112 samples previously tested via manual real-time PCR, the concordance in TTV detection was 93% between the assays. When the TTV levels were compared, the overall agreement between the methods, as assessed using Passing-Bablok linear regression and Bland-Altman analyses, was excellent. In summary, we validated a highly sensitive and accurate method for the diagnostic use of TTV quantification on a fully automated Hologic Panther Fusion System. This will greatly improve the turnaround time for TTV testing and better support the laboratory diagnosis of this new viral biomarker.
Topics: Real-Time Polymerase Chain Reaction; Viremia; Humans; Viral Load; DNA Virus Infections; Sensitivity and Specificity; Torque teno virus; DNA, Viral; Limit of Detection; Reproducibility of Results; Automation, Laboratory
PubMed: 38932255
DOI: 10.3390/v16060963 -
Viruses Jun 2024Recently, a multiplex PCR-based titration (MPBT) assay was developed for simultaneous determination of infectious titers of all three Sabin strains of the oral...
Recently, a multiplex PCR-based titration (MPBT) assay was developed for simultaneous determination of infectious titers of all three Sabin strains of the oral poliovirus vaccine (OPV) to replace the conventional CCID assay, which is both time-consuming and laborious. The MPBT assay was shown to be reproducible, robust and sensitive. The conventional and MPBT assays showed similar results and sensitivity. The MPBT assay can be completed in two to three days, instead of ten days for the conventional assay. To prevent attenuated vaccine strains of poliovirus from reversion to virulence, a novel, genetically stable OPV (nOPV) was developed by modifying the genomes of conventional Sabin strains used in OPV. In this work, we evaluated the MPBT assay as a rapid screening tool to support trivalent nOPV (tnOPV) formulation development by simultaneous titration of the three nOPV strains to confirm stability as needed, for the selection of the lead tnOPV formulation candidate. We first assessed the ability of the MPBT assay to discriminate a 0.5 log titer difference by titrating the two tnOPV samples (undiluted and threefold-diluted) on the same plate. Once the assay was shown to be discriminating, we then tested different formulations of tnOPV drug products (DPs) that were subjected to different exposure times at 37 °C (untreated group and treated groups: 2 and 7 days at 37 °C), and to three freeze and thaw (FT) cycles. Final confirmation of the down selected formulation candidates was achieved by performing the conventional CCID assay, comparing the stability of untreated and treated groups and FT stability testing on the top three candidates. The results showed that the MPBT assay generates similar titers as the conventional assay. By testing two trivalent samples in the same plate, the assay can differentiate a 0.5 log difference between the titers of the tested nOPV samples. Also, the assay was able to detect the gradual degradation of nOPV viruses with different formulation compositions and under different time/temperature conditions and freeze/thaw cycles. We found that there were three tnOPV formulations which met the stability criteria of less than 0.5 log loss after 2 days' exposure to 37 ℃ and after three FT cycles, maintaining the potency of all three serotypes in these formulations. The ability of the MPBT assay to titrate two tnOPV lots (six viruses) in the same plate makes it cheaper and gives it a higher throughput for rapid screening. The assay detected the gradual degradation of the tnOPV and was successful in the selection of optimal formulations for the tnOPV. The results demonstrated that the MPBT method can be used as a stability indicating assay to assess the thermal stability of the nOPV. It can be used for rapid virus titer determination during the vaccine manufacturing process, and in clinical trials. The MPBT assay can be automated and applied for other viruses, including those with no cytopathic effect.
Topics: Poliovirus Vaccine, Oral; Poliovirus; Humans; Multiplex Polymerase Chain Reaction; Poliomyelitis; Vaccines, Attenuated; Reproducibility of Results; Sensitivity and Specificity
PubMed: 38932253
DOI: 10.3390/v16060961 -
Viruses Jun 2024This study aimed to determine the incidence and etiological, seasonal, and genetic characteristics of respiratory viral coinfections involving severe acute respiratory...
This study aimed to determine the incidence and etiological, seasonal, and genetic characteristics of respiratory viral coinfections involving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Between October 2020 and January 2024, nasopharyngeal samples were collected from 2277 SARS-CoV-2-positive patients. Two multiplex approaches were used to detect and sequence SARS-CoV-2, influenza A/B viruses, and other seasonal respiratory viruses: multiplex real-time polymerase chain reaction (PCR) and multiplex next-generation sequencing. Coinfections of SARS-CoV-2 with other respiratory viruses were detected in 164 (7.2%) patients. The most common co-infecting virus was respiratory syncytial virus (RSV) (38 cases, 1.7%), followed by bocavirus (BoV) (1.2%) and rhinovirus (RV) (1.1%). Patients ≤ 16 years of age had the highest rate (15%) of mixed infections. Whole-genome sequencing produced 19 complete genomes of seasonal respiratory viral co-pathogens, which were subjected to phylogenetic and amino acid analyses. The detected influenza viruses were classified into the genetic groups 6B.1A.5a.2a and 6B.1A.5a.2a.1 for A(H1N1)pdm09, 3C.2a1b.2a.2a.1 and 3C.2a.2b for A(H3N2), and V1A.3a.2 for the B/Victoria lineage. The RSV-B sequences belonged to the genetic group GB5.0.5a, with HAdV-C belonging to type 1, BoV to genotype VP1, and PIV3 to lineage 1a(i). Multiple amino acid substitutions were identified, including at the antibody-binding sites. This study provides insights into respiratory viral coinfections involving SARS-CoV-2 and reinforces the importance of genetic characterization of co-pathogens in the development of therapeutic and preventive strategies.
Topics: Humans; Coinfection; SARS-CoV-2; COVID-19; Middle Aged; Adult; Female; Male; Adolescent; Phylogeny; Child, Preschool; Child; Aged; Young Adult; Infant; Respiratory Tract Infections; Rhinovirus; Influenza A virus; Respiratory Syncytial Virus, Human; Nasopharynx; Whole Genome Sequencing; China; Seasons; Aged, 80 and over; Genome, Viral; Influenza B virus
PubMed: 38932250
DOI: 10.3390/v16060958