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Background: Food-borne pathogen Listeria monocytogenes is abundantly present in nature and accountable for sporadic and epidemic cases of listeriosis in humans. The objective of this study was to screen common food sources for L. monocytogenes using biochemical and molecular methods to detect and characterise its toxin genes as well as for biofilm formation. Methods: A total of 92 samples, comprising dairy and street food products, were randomly collected from various sources for this investigation. The collected samples were processed for biochemical and molecular methods to detect L. monocytogenes. Additionally, virulence factors associated genes, antibiogram profiles and biofilm formation related assays were determined. Results: L. monocytogenes presence was confirmed using molecular detection methods targeting prs and lmo1030 genes, along with MALDI-TOF MS. Following 16 S rRNA sequencing, the identified Listeria species were further categorised into two groups. L. monocytogenes was detected in two (2.17%) food samples tested (L-23 and L-74). Multiplex PCR indicated the presence of seven virulence-related genes in L. monocytogenes isolates, i.e., inlA, inlB, prfA, iap, actA, plcB, and hlyA. In addition, 17 antibiotics were tested, whereby two isolates showed resistance to clindamycin and azithromycin, while one isolate (L-74) was also resistant to nalidixic acid, co-trimoxazole, ampicillin, norfloxacin, and cefotaxime. L-23 and L-74 isolates showed biofilm formation, especially at pH 8.6 and 37°C. Conclusions: Besides the demonstration of the presence of L. monocytogenes in some dairy and street food products, this study underscores the need to increase the standards of hygiene on the one hand and the importance of the surveillance of food-borne pathogens on the other.

DNA-based molecular markers have great importance among other methods used for the authentication, detection, and identification of medicinal herbal species. Currently, it is more common to identify the medicinal herbal species (monoherbal or polyherbal forms) morphologically by using sensory, macroscopic, and microscopic methods. DNA-based markers made an easy for accurate detection of herbal species by using the polymerase chain reaction (PCR) which involves in vitro amplification of a particular region of DNA sequence.In the current study, we used heterogenic parts for isolation of DNA from twelve important medicinal herbal species followed by purity determination, and yield calculation. We optimized a PCR reaction using universal primer sets to amplify the target DNA followed by DNA sequencing, and species identification. We also performed phylogenetic analysis for determining the evolutionary relationship between the herbal species, by using MEGAX32 software. Further, we prepared adulterated herbal species samples to validate the method.The method was able to amplify the target gene through PCR in 11 out of 12 herbal species samples (sensitivity 91.66%).The DNA from cinnamon could not yield a truly amplified product. On DNA sequencing, all the amplified products were identified as true herbal species (specificity 100%). In the adulterated samples, non-specific DNA bands were observed after performing the PCR reaction, indicating the mixing of more than one herbal species.To conclude, DNA sequencing-based molecular analysis is advantageous for the correct identification, and detection of adulterated herbal species.

Competing Interests: Declaration of competing interest RAN is a paid consultant for ModernaTX and BioNTech. SJP is a consultant for Next Gen Diagnostics. GGR is scientific advisor of Resitell (Muttenz, Switzerland), a start-up implicated in nanomotion-based measure of antimicrobial resistance. DH is managing director and shareholder of the company Ridom GmbH that develops the SeqSphere + tool. AE is scientific advisor of Sefunda (Muttenz, Switzerland).

Seven public water systems in Minnesota, USA were analyzed from one to five times over a two-year period to assess temporal changes in the concentrations of total bacteria, Legionella spp., and Legionella pneumophila from source (i.e., raw water) through the water treatment process to the end water user. Bacterial biomass was collected by filtering large volumes of raw water (12 to 425 L, median: 38 L) or finished and tap water (27 to 1205 L, median: 448 L) using ultrafiltration membrane modules. Quantitative PCR (qPCR) was then used to enumerate all bacteria (16S rRNA gene fragments), all Legionella spp. (ssrA), and Legionella pneumophila (mip). Total coliforms, Escherichia coli, and L. pneumophila also were quantified in the water samples via cultivation. Median concentrations of total bacteria and Legionella spp. (ssrA) in raw water (8.5 and 4.3 log copies/L, respectively) decreased by about 2 log units during water treatment. The concentration of Legionella spp. (ssrA) in water collected from distribution systems inversely correlated with the total chlorine concentration for chloraminated systems significantly (p = 0.03). Although only 8 samples were collected from drinking water distribution systems using free chlorine as a residual disinfectant, these samples had significantly lower concentrations of Legionella spp. (ssrA) than samples collected from the chloraminated systems (p = 5 × 10 -4 ). There was considerable incongruity between the results obtained via cultivation-independent (qPCR) and cultivation-dependent assays. Numerous samples were positive for L. pneumophila via cultivation, none of which tested positive for L. pneumophilia (mip) via qPCR. Conversely, a single sample tested positive for L. pneumophilia (mip) via qPCR, but this sample tested negative for L. pneumophilia via cultivation. Overall, the results suggest that conventional treatment is effective at reducing, but not eliminating, Legionella spp. from surface water supplies and that residual disinfection is effective at suppressing these organisms within drinking water distribution systems., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Timothy M. LaPara and Raymond M. Hozalski report financial support was provided by Minnesota Environment and Natural Resources Trust Fund. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Food-borne pathogen Listeria monocytogenes is abundantly present in nature and accountable for sporadic and epidemic cases of listeriosis in humans. The objective of this study was to screen common food sources for L. monocytogenes using biochemical and molecular methods to detect and characterise its toxin genes as well as for biofilm formation., Methods: A total of 92 samples, comprising dairy and street food products, were randomly collected from various sources for this investigation. The collected samples were processed for biochemical and molecular methods to detect L. monocytogenes. Additionally, virulence factors associated genes, antibiogram profiles and biofilm formation related assays were determined., Results: L. monocytogenes presence was confirmed using molecular detection methods targeting prs and lmo1030 genes, along with MALDI-TOF MS. Following 16 S rRNA sequencing, the identified Listeria species were further categorised into two groups. L. monocytogenes was detected in two (2.17%) food samples tested (L-23 and L-74). Multiplex PCR indicated the presence of seven virulence-related genes in L. monocytogenes isolates, i.e., inlA, inlB, prfA, iap, actA, plcB, and hlyA. In addition, 17 antibiotics were tested, whereby two isolates showed resistance to clindamycin and azithromycin, while one isolate (L-74) was also resistant to nalidixic acid, co-trimoxazole, ampicillin, norfloxacin, and cefotaxime. L-23 and L-74 isolates showed biofilm formation, especially at pH 8.6 and 37°C., Conclusions: Besides the demonstration of the presence of L. monocytogenes in some dairy and street food products, this study underscores the need to increase the standards of hygiene on the one hand and the importance of the surveillance of food-borne pathogens on the other., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: The median age for Prostate Cancer (PCa) diagnosis is 66 years, but 10% are diagnosed before 55 years. Studies on early-onset PCa remain both limited and controversial. This investigation sought to identify and characterize germline variants within Brazilian PCa patients classified as either early or later onset disease., Methods: Peripheral blood DNA from 71 PCa patients: 18 younger (≤ 55 years) and 53 older (≥ 60 years) was used for Targeted DNA sequencing of 20 genes linked to DNA damage response, transcriptional regulation, cell cycle, and epigenetic control. Subsequent genetic variant identification was performed and variant functional impacts were analyzed with in silico prediction., Results: A higher frequency of variants in the BRCA2 and KMT2C genes across both age groups. KMT2C has been linked to the epigenetic dysregulation observed during disease progression in PCa. We present the first instance of KMT2C mutation within the blood of Brazilian PCa patients. Furthermore, out of the recognized variants within the KMT2C gene, 7 were designated as deleterious. Thirteen deleterious variants were exclusively detected in the younger group, while the older group exhibited 37 variants. Within these findings, 4 novel variants emerged, including 1 designated as pathogenic., Conclusions: Our findings contribute to a deeper understanding of the genetic factors associated with PCa susceptibility in different age groups, especially among the Brazilian population. This is the first investigation to explore germline variants specifically in younger Brazilian PCa patients, with high relevance given the genetic diversity of the population in Brazil. Additionally, our work presents evidence of functionally deleterious germline variants within the KMT2C gene among Brazilian PCa patients. The identification of novel and functionally significant variants in the KMT2C gene emphasizes its potential role in PCa development and warrants further investigation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The DNA Commission of the International Society for Forensic Genetics (ISFG) has developed a set of nomenclature recommendations for short tandem repeat (STR) sequences. These recommendations follow the 2016 considerations of the DNA Commission of the ISFG, incorporating the knowledge gained through research and population studies in the intervening years. While maintaining a focus on backward compatibility with the CE data that currently populate national DNA databases, this report also looks to the future with the establishment of recommended minimum sequence reporting ranges to facilitate interlaboratory comparisons, automated solutions for sequence-based allele designations, a suite of resources to support bioinformatic development, guidance for characterizing new STR loci, and considerations for incorporating STR sequences and other new markers into investigative databases., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Bruce Budowle: Currently Consultant with Verogen., (Published by Elsevier B.V.)