Ecological Distribution of Virulent Multidrug-Resistant Staphylococcus aureus in Livestock, Environment, and Dairy Products

Staphylococcus aureus is one of the most common causes of mastitis, leading to severe economic losses in the dairy industry. It is also zoonotic, with potential risks to public health. This study aimed to detect the occurrence of S. aureus-resistant strains isolated from cattle, buffalo, their environment, milk and dairy products; and to investigate the extent of animal, ecological, and food contamination by methicillin-resistant (MRSA) or enterotoxigenic S. aureus. Samples (n = 350) were collected from four animal (two cattle and two buffalo) farms, i.e., their environment. Thirty Karish cheese samples were collected from 10 markets in Mansoura, Egypt. S. aureus was detected in 17.9%, 17.6%, and 16.7% of samples collected from cattle, buffalo and Karish cheese, respectively. About 19% of isolated S. aureus strains carried the mecA gene. The distribution of the mecA gene was high in isolates from Karish cheese (60%), followed by samples collected from buffalo (16.2%) and cattle (16%). More than 34% of isolated S. aureus strains were enterotoxigenic, and the presence of enterotoxin genes was higher in isolates from Karish cheese (80%) than those from cattle (48%) and buffalo (18.9%). The most predominant enterotoxin gene among isolated S. aureus strains was the sea gene (26.9%), followed by sec (4.5%) and sed (3%) genes. Isolated strains were resistant to clindamycin (100%), kanamycin (97%), nalidixic acid (86.6%), cefotaxime (73.1%) sulphamethazole—trimethoprim (65.6%). Meanwhile, 95.5%, 94%, 86.6% and 77.7% of S. aureus strains were sensitive to ciprofloxacin, amikacin, imipenem and both cefoxitin and gentamycin, respectively. In conclusion, the presence of enterotoxigenic- and methicillin-resistant S. aureus strains in animals, their environment, and dairy products represents a public health concern, particularly in small-scale dairy farms in Egypt. To reduce the risk of infection of livestock and humans with resistant strains, strict regulations and guidelines for antimicrobial use in such a system are urgently required

Whole-genome sequencing of Listeria innocua recovered from retail milk and dairy products in Egypt

The similarity of the Listeria innocua genome with Listeria monocytogenes and their presence in the same niche may facilitate gene transfer between them. A better understanding of the mechanisms responsible for bacterial virulence requires an in-depth knowledge of the genetic characteristics of these bacteria. In this context, draft whole genome sequences were completed on five L. innocua isolated from milk and dairy products in Egypt. The assembled sequences were screened for antimicrobial resistance and virulence genes, plasmid replicons and multilocus sequence types (MLST); phylogenetic analysis of the sequenced isolates was also performed. The sequencing results revealed the presence of only one antimicrobial resistance gene, fosX, in the L. innocua isolates. However, the five isolates carried 13 virulence genes involved in adhesion, invasion, surface protein anchoring, peptidoglycan degradation, intracellular survival, and heat stress; all five lacked the Listeria Pathogenicity Island 1 (LIPI-1) genes. MLST assigned these five isolates into the same sequence type (ST), ST-1085; however, single nucleotide polymorphism (SNP)-based phylogenetic analysis revealed 422–1,091 SNP differences between our isolates and global lineages of L. innocua. The five isolates possessed an ATP-dependent protease (clpL) gene, which mediates heat resistance, on a rep25 type plasmids. Blast analysis of clpL-carrying plasmid contigs showed approximately 99% sequence similarity to the corresponding parts of plasmids of L. monocytogenes strains 2015TE24968 and N1-011A previously isolated from Italy and the United States, respectively. Although this plasmid has been linked to L. monocytogenes that was responsible for a serious outbreak, this is the first report of L. innocua containing clpL-carrying plasmids. Various genetic mechanisms of virulence transfer among Listeria species and other genera could raise the possibility of the evolution of virulent strains of L. innocua. Such strains could challenge processing and preservation protocols and pose health risks from dairy products. Ongoing genomic research is necessary to identify these alarming genetic changes and develop preventive and control measures

Genska karakterizacija, kloniranje i ekspresija Toll-like receptora 1 mRNA nilske tilapije (Oreochromis niloticus)

Toll-like receptors (TLRs) are the most studied group of pathogen recognition receptor categories that detects infectious agents in vertebrates. Fish TLRs exhibit clear, distinct features, structure and a larger diversity than in other vertebrates. This study focused on identifying and detecting the structure of Oreochromis niloticus (Nile tilapia) Toll- like receptor-1 (TLR1|) as a model in freshwater bony fish. The full-length cDNA sequence of Oreochromis niloticus TLR1 mRNA was cloned. Cloning and sequence analysis revealed that the complete cDNA sequence of Oreochromis niloticus TLR1 consists of 2355 base pairs and encodes a polypeptide of 785 amino acids. The molecular analysis of the amino acid sequence indicated that Oreochromis niloticus TLR1 has the standard structural features and major components of amino acids of TLR family members, and is considered an orthologue to the vertebrate TLR1, not a paralogue. The translated amino acid analysis showed 96%, 88%, 85%, and 85% degrees of identity with Zebra Mbuna, Sea bass, Damsel fish, and Clownfish, respectively; and showed 66% identity t with electric eels and 61% with starlets. Phylogenetic analysis revealed that the Nile tilapia TLR1 is closely related to Larimichthys crocea, Epinephelus coioides, and Takifugu rubripes TLR1. Oreochromis niloticus TLR1 was expressed in the kidneys, brain, spleen, intestines, muscle, liver, gills, heart and skin. Quantitative RT-PCR showed differences in the expression levels between the tested tissues. In conclusion, this study is the first report (according to our knowledge) and provides a complete molecular and functional characterization of Oreochromis niloticus toll-like receptor 1, which is considered to be functionally orthologous to TLR1 in other species models.Toll-like receptori (TLR) najviše su istraživana skupina receptora za prepoznavanje uzročnika bolesti u kralježnjaka. TLR u riba pokazuju jasna razlikovna svojstva, strukturu i veliku raznolikost u odnosu na druge kralježnjake. Ovo je istraživanje usredotočeno na identifikaciju i otkrivanje Toll-like receptora 1 (TLR1) u nilske tilapije (Oreochromis niloticus) kao predstavnika slatkovodnih riba. Klonirana je puna sekvencija cDNA TLR1 mRNA. Utvrđeno je da se kompletna sekvencija cDNA TLR1 nilske tilapije sastoji od 2355 baznih parova i kodira polipeptid od 785 aminokiselina. Molekularna analiza sekvencija aminokiselina upućuje na to da TLR1 nilske tilapije ima standardna strukturna svojstva i glavne komponente porodice TLR receptora i smatra se ortologom, ne paralogom TLR1 kralježnjaka. Analiza prevedenih aminokiselina pokazala je stupanj identičnost od 96 % s mbuna zebrom, 88 % s lubinom, 85 % s damsel ribom i 85 % s ribom klaun, dok je stupanj identičnosti s električnom jeguljom bio 66 %, a s ribom starlet 61 %. Filogenetska analiza pokazala je da je TLR1 nilske tilapije usko povezan s TLR1 vrsta Larimichthys crocea, Epinephelus coioides i Takifugu rubripes. TLR1 nilske tilapije bio je izražen u bubrezima, mozgu, slezeni, crijevima, mišiću, jetri, škrgama, srcu i na koži. Kvantitativni RT-PCR pokazao je razlike u razini ekspresije među testiranim tkivima. Prema našim podacima ovo je istraživanje prvo koje donosi kompletnu molekularnu i funkcionalnu karakterizaciju Toll-like receptora 1 nilske tilapije, te se smatra funkcionalnim ortologom TLR1 u drugih vrsta

Tenacibaculosis caused by Tenacibaculum maritimum: Updated knowledge of this marine bacterial fish pathogen

Tenacibaculosis occurs due to the marine bacterial pathogen Tenacibaculum maritimum. This ulcerative disease causes high mortalities for various marine fish species worldwide. Several external clinical signs can arise, including mouth erosion, epidermal ulcers, fin necrosis, and tail rot. Research in the last 15 years has advanced knowledge on the traits and pathogenesis mechanisms of T. maritimum. Consequently, significant progress has been made in defining the complex host-pathogen relationship. Nevertheless, tenacibaculosis pathogenesis is not yet fully understood. Continued research is urgently needed, as demonstrated by recent reports on the re-emerging nature of tenacibaculosis in salmon farms globally. Current sanitary conditions compromise the development of effective alternatives to antibiotics, in addition to hindering potential preventive measures against tenacibaculosis. The present review compiles knowledge of T. maritimum reported after the 2006 review by Avendaño-Herrera and colleagues. Essential aspects are emphasized, including antigenic and genomic characterizations and molecular diagnostic procedures. Further summarized are the epidemiological foundations of the T. maritimum population structure and elucidations as to the virulence mechanisms of pathogenic isolates, as found using biological, microbiological, and genomic techniques. This comprehensive source of reference will undoubtable serve in tenacibaculosis prevention and control within the marine fish farming industry. Lastly, knowledge gaps and valuable research areas are indicated as potential guidance for future studies

The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

Prevalence, molecular typing, and antimicrobial resistance of bacterial pathogens isolated from ducks

Aim: This study aimed to investigate the prevalence of different bacterial species affecting ducks as well as demonstrating the antimicrobial susceptibility and molecular typing of the isolated strains. Materials and Methods: A total of 500 samples were randomly collected from different duck farms at Ismailia Governorate, Egypt. The collected samples were subjected to the bacteriological examination. Polymerase chain reaction (PCR) was applied for amplification of Kmt1 gene of Pasteurella multocida and X region of protein-A (spA) gene of the isolated Staphylococcus aureus strains to ensure their virulence. The antibiotic sensitivity test was carried out. Results: The most common pathogens isolated from apparently healthy and diseased ducks were P. multocida (10.4% and 25.2%), Escherichia coli (3.6% and 22.8%), Staphylococcus epidermidis (10% and 8.8%), Pseudomonas aeruginosa (2% and 10%), and Proteus vulgaris (0.8% and 10%), respectively. In addition, S. aureus and Salmonella spp. were isolated only from the diseased ducks with prevalence (12.2%) and (2.8%), respectively. Serotyping of the isolated E. coli strains revealed that 25 E. coli strains were belonged to five different serovars O1, O18, O111, O78, and O26, whereas three strains were untypable. Salmonella serotyping showed that all the isolated strains were Salmonella Typhimurium. PCR revealed that four tested P. multocida strains were positive for Kmt1 gene with specific amplicon size 460 bp, while three strains were negative. In addition, all the tested S. aureus strains were positive for spA gene with specific amplicon size 226 bp. The antibiotic sensitivity test revealed that most of the isolated strains were sensitive to enrofloxacin, norfloxacin, and ciprofloxacin. Conclusion: P. multocida is the most predominant microorganism isolated from apparently healthy and diseased ducks followed by E. coli and Staphylococci. The combination of both phenotypic and genotypic characterization is more reliable an epidemiological tool for identification of bacterial pathogens affecting ducks

Molecular Typing, Antibiogram and PCR-RFLP Based Detection of Aeromonas hydrophila Complex Isolated from Oreochromis niloticus

Motile Aeromonas septicemia is a common bacterial disease that affects Oreochromis niloticus and causes tremendous economic losses globally. In order to investigate the prevalence, molecular typing, antibiogram and the biodiversity of Aeromonas hydrophila complex, a total of 250 tilapia (Oreochromis niloticus) were collected randomly from 10 private tilapia farms (25 fish/farm) at El-Sharkia Governorate, Egypt. The collected fish were subjected to clinical and bacteriological examinations. The majority of infected fish displayed ulcerative necrosis, exophthalmia, and internal signs of hemorrhagic septicemia. The prevalence of A. hydrophia complex was 13.2%, where the liver was the most predominant affected organ (54.1%). Polymerase chain reaction (PCR) was used to verify the identification of A. hydrophila complex using one set of primers targeting gyrB as well as the detection of virulent genes (aerA, alt, and ahp). All isolates were positive for the gyrB-conserved gene and harbored aerA and alt virulence genes. However, none of those isolates were positive for the ahp gene. The antimicrobial sensitivity was carried out, where the recovered strains were completely sensitive to ciprofloxacin and highly resistant to amoxicillin. All retrieved strains showed the same phenotypic characteristics and were identical based on the restriction fragment length polymorphism (RFLP). Experimentally challenged fish presented a high mortality rate (76.67%) and showed typical signs as in naturally infected ones. In conclusion, the synergism of phenotypic and genotypic characterization is a valuable epidemiological tool for the diagnosis of A. hydrophila complex. RFLP is a fundamental tool for monitoring the biodiversity among all retrieved strains of A. hydrophia

The Pharmacological Activity, Biochemical Properties, and Pharmacokinetics of the Major Natural Polyphenolic Flavonoid: Quercetin

Flavonoids are a class of natural substances present in plants, fruits, vegetables, wine, bulbs, bark, stems, roots, and tea. Several attempts are being made to isolate such natural products, which are popular for their health benefits. Flavonoids are now seen as an essential component in a number of cosmetic, pharmaceutical, and medicinal formulations. Quercetin is the major polyphenolic flavonoid found in food products, including berries, apples, cauliflower, tea, cabbage, nuts, and onions that have traditionally been treated as anticancer and antiviral, and used for the treatment of allergic, metabolic, and inflammatory disorders, eye and cardiovascular diseases, and arthritis. Pharmacologically, quercetin has been examined against various microorganisms and parasites, including pathogenic bacteria, viruses, and Plasmodium, Babesia, and Theileria parasites. Additionally, it has shown beneficial effects against Alzheimer’s disease (AD), and this activity is due to its inhibitory effect against acetylcholinesterase. It has also been documented to possess antioxidant, antifungal, anti-carcinogenic, hepatoprotective, and cytotoxic activity. Quercetin has been documented to accumulate in the lungs, liver, kidneys, and small intestines, with lower levels seen in the brain, heart, and spleen, and it is extracted through the renal, fecal, and respiratory systems. The current review examines the pharmacokinetics, as well as the toxic and biological activities of quercetin

A First Report of Molecular Typing, Virulence Traits, and Phenotypic and Genotypic Resistance Patterns of Newly Emerging XDR and MDR <i>Aeromonas veronii</i> in <i>Mugil seheli</i>

Aeromonas veronii is associated with substantial economic losses in the fish industry and with food-borne illness in humans. This study aimed to determine the prevalence, antibiogram profiles, sequence analysis, virulence and antimicrobial resistance genes, and pathogenicity of A. veronii recovered from Mugil seheli. A total of 80 fish were randomly gathered from various private farms in Suez Province, Egypt. Subsequently, samples were subjected to clinical, post-mortem, and bacteriological examinations. The retrieved isolates were tested for sequence analysis, antibiogram profile, pathogenicity, and PCR detection of virulence and resistance genes. The prevalence of A. veronii in the examined M. seheli was 22.5 % (18/80). The phylogenetic analyses revealed that the tested A. veronii strains shared high genetic similarity with other A. veronii strains from India, UK, and China. Using PCR it was revealed that the retrieved A. veronii isolates harbored the aerA, alt, ser, ompAII, act, ahp, and nuc virulence genes with prevalence of 100%, 82.9%, 61.7%, 55.3%, 44.7%, 36.17%, and 29.8%, respectively. Our findings revealed that 29.8% (14/47) of the retrieved A. veronii strains were XDR to nine antimicrobial classes and carried blaTEM, blaCTX-M, blaSHV,tetA, aadA1, and sul1 resistance genes. Likewise, 19.1% (9/47) of the obtained A. veronii strains were MDR to eight classes and possessed blaTEM, blaCTX-M, blaSHV,tetA, aadA1, and sul1 genes. The pathogenicity testing indicated that the mortality rates positively correlated with the prevalence of virulence-determinant genes. To our knowledge, this is the first report to reveal the occurrence of XDR and MDR A. veronii in M. seheli, an emergence that represents a risk to public health. Emerging XDR and MDR A. veronii in M. seheli frequently harbored aerA, alt, ser, ompAII, and act virulence genes, and blaTEM, sul1, tetA, blaCTX-M, blaSHV, and aadA1 resistance genes

T cell subsets, regulatory T, regulatory B cells and proinflammatory cytokine profile in Schistosoma haematobium associated bladder cancer: First report from Upper Egypt.

BackgroundThe function of different populations of the immune system in bladder cancer (BCa) is well established. However, the cohesive role of the immune cell profile of schistosomal BCa at systemic and tissue levels is still lacking, especially in endemic countries. The balance hypothesized between protumorigenic and antitumor molecules determines the prognosis of tumor progression. This study aimed to investigate the frequency of T cell subsets at both blood and tumor tissue, regulatory T(Treg), regulatory B cells (Breg) and proinflammatory cytokines in S. haematobium-related BCa patients in Egypt.Methodology/principal findingsThe frequency of T cell subsets at both blood and tumor tissue, regulatory T(Treg), regulatory B cells (Breg) were studied by flow cytometry and proinflammatory cytokines by ELISA in S. haematobium-related BCa patients in Egypt. The results indicated a significant increase in the activity of T-cell populations, particularly CD3+, CD4+, and regulatory T cells (Tregs), and a decrease in cytotoxic CD8+ T cells in the patient group. An increased proportion of CD19+CD24+CD38+ Bregs and proinflammatory cytokines (IL-1β, IL-6, and TNF-α) was also observed. However, T-cell subpopulations in the tumor microenvironment showed a significant reduction in cancer patients compared to controls. Moreover, positive correlations were observed between the frequencies of Bregs and Tregs, suggesting the promotion of cancer progression besides their relation to the intensity of schistosomal infection.Conclusions/significanceTrapped Schistosoma haematobium eggs in bladder tissue might lead to persistent inflammation that contributes to immunomodulation and promotes tumor progression, as evidenced by the increase in peripheral T helper, Tregs, Bregs and serum tumor-promoting cytokines. Considering the role and integrated functions of specific immune responses in BCa could help future diagnostic and therapeutic implications