Multidrug-resistant Escherichia coli in Raw Milk: Molecular Characterization and the potential impact of camel's Urine as an Antibacterial Agent

Carbapenem-resistant Enterobacteriaceae from dairy cattle milk: A systematic review and meta-analysis

Carbapenem-resistant Enterobacteriaceae (CRE) have been detected in dairy cattle milk, raising concerns about public health risks. This study aimed to assess the global prevalence of CRE in dairy cattle milk through a systematic review and meta-analysis, following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Retrieved articles from four databases were initially screened based on predefined inclusion criteria. The meta-analysis included 49 studies (2011-2024), covering 28,134 milk samples and 3462 Enterobacteriaceae isolates globally. Data from the full text were extracted to a Microsoft Excel spreadsheet and analysed using the 'meta' R package in R v.4.3.0 software for pooled prevalence and subgroup meta-analysis with a random-effects for logit transformation. Heterogeneity was assessed using Cochran's Q statistic (χ2), p-value and I2 statistic. Publication bias and sensitivity were evaluated using Egger's test, funnel plot, trim and fill plot, and leave-one-out test. Globally, the prevalence of CRE in dairy cattle milk was 0.73 % (95 % CI, 0.37-1.41). Subgroup meta-analysis based on continent, sample type, Enterobacteriaceae species, diagnostic method, antibiotic type, and interpretation guideline revealed no significant differences among the criteria within the subgroup. Although the overall pooled prevalence of CRE in dairy cattle milk is relatively low, it raises public health concern regarding raw milk consumption. This emphasizes the need for regular monitoring with in a One Health framework for CRE in the dairy industry to anticipate potential transmission between humans, animals, and the environment.

Prevalence and Antibiotic Resistance of Escherichia coli Isolated from Raw Cow's Milk

Escherichia coli (E. coli) is one of the most common pathogens in both humans and livestock. This study aimed to investigate the prevalence of E. coli isolated from raw cow milk and evaluate its antimicrobial resistance rates. A total of 1696 milk samples were collected from Romanian dairy farms from 2018 to 2022. E. coli was isolated on various selective agar media, such as Cled agar and Columbia Agar with 5% Sheep Blood. The identification of E. coli was performed by MALDI-TOF MS. E. coli isolates were tested for their susceptibility against 18 commonly used antibiotics in a disk diffusion method. The overall prevalence of E. coli was 22.45% of all isolated pathogens. Antibiogram analysis revealed that 27.51% of E. coli isolates from milk were multidrug-resistant. Resistance was highest for penicillin-novobiocin (87.78%), followed by streptomycin (53.7%). Resistance to six drugs (amoxicillin, streptomycin, kanamycin-cephalexin, marbofloxacin, ampicillin) showed a significant increasing trend over time, while for two drugs (penicillin G-framycetin, doxycycline), a significant decrease was observed. Our results suggest that milk can be a reservoir of bacteria with the potential for infection in humans via the food chain. Furthermore, there is a need for surveillance and monitoring to control the increase in resistance to currently used antimicrobials in dairy farms because the occurrence of multidrug-resistant E. coli isolated from milk poses a health hazard to consumers.

Factors influencing the bioactivity of natural matrices: The case of osmolarity-dependent modulation of cell viability by different dilutions of camel urines

The widespread practice of dromedary urinotherapy as a remedy for various illnesses, including cancer, is well-established in traditional dromedary countries. Researchers attempted to demonstrate anticancer properties of camel urine through in vitro experiments with debated outcomes. Notably, two critical aspects remained unexplored in those assays: (i) the osmolarity of tested urines, which can significantly influence in vitro results; (ii) the potential morphological changes of cells, following exposure to camel urines. In this study, we addressed these gaps by evaluating the osmolarity-dependent modulation of cell viability in human renal cell lines. In this regard, we assessed the impact of hyperosmolar mannitol-based solutions and dromedary urine on the viability and morphology of human non-tumor (HK2) and tumor renal cells (Caki-1). The results indicate that cell viability or morphology in both HK2 and Caki-1 cells are not significantly affected only if mannitol-induced hyperosmolarity is lower than 500 mOsm/L. Notably, when exposed to urine solution, diluted to <500 mOsm/L, statistically significant antiproliferative effects were observed primarily in Caki-1 cells (in presence of two out of ten tested urine samples). Conversely, alterations in cell morphology were observed exclusively in HK2 cells when exposed to the same diluted camel urines. In order to investigate, at molecular level, the observed antiproliferative effects, a preliminary metabolomics analysis of the tested urine samples was performed to identify potential bioactive compounds. The Nuclear Magnetic Resonance (NMR) metabolic profiling revealed the presence of three antioxidant compounds, namely trigonelline, pyruvic acid and N-acetylglucosamine. In conclusion, our results highlight the importance of considering the critical role of osmolarity when evaluating the bioactive properties of camel urine in vitro, which should not be used to treat any illness as it is. Conversely, it can be considered the possibility to use camel urines as a source of bioactive compounds.

Proteome analysis, genetic characterization, and antibiotic resistance patterns of Klebsiella pneumoniae clinical isolates

Klebsiella pneumoniae (K. pneumoniae) is a member of the ESKAPE group and is responsible for severe community and healthcare-associated infections. Certain Klebsiella species have very similar phenotypes, which presents a challenge in identifying K. pneumoniae. Multidrug-resistant K. pneumoniae is also a serious global problem that needs to be addressed. A total of 190 isolates were isolated from urine (n = 69), respiratory (n = 52), wound (n = 48) and blood (n = 21) samples collected from various hospitals in the Al-Qassim, Saudi Arabia, between March 2021 and October 2022. Our study aimed to rapidly and accurately detect K. pneumoniae using the Peptide Mass Fingerprinting (PMF) technique, confirmed by real-time PCR. Additionally, screening for antibiotic susceptibility and resistance was conducted. The primary methods for identifying K. pneumoniae isolates were culture, Gram staining, and the Vitek® 2 ID Compact system. An automated MALDI Biotyper (MBT) instrument was used for proteome identification, which was subsequently confirmed using SYBR green real-time polymerase chain reaction (real-time PCR) and microfluidic electrophoresis assays. Vitek® 2 AST-GN66 cards were utilized to evaluate the antimicrobial sensitivity of K. pneumoniae isolates. According to our results, Vitek® 2 Compact accurately identified 178 out of 190 (93.68%) K. pneumoniae isolates, while the PMF technique correctly detected 188 out of 190 (98.95%) isolates with a score value of 2.00 or higher. Principal component analysis was conducted using MBT Compass software to classify K. pneumoniae isolates based on their structure. Based on the analysis of the single peak intensities generated by MBT, the highest peak values were found at 3444, 5022, 5525, 6847, and 7537 m/z. K. pneumoniae gene testing confirmed the PMF results, with 90.53% detecting entrobactin, 70% detecting 16 S rRNA, and 32.63% detecting ferric iron uptake. The resistance of the K. pneumoniae isolates to antibiotics was as follows: 64.75% for cefazolin, 62.63% for trimethoprim/sulfamethoxazole, 59.45% for ampicillin, 58.42% for cefoxitin, 57.37% for ceftriaxone, 53.68% for cefepime, 52.11% for ampicillin-sulbactam, 50.53% for ceftazidime, 52.11% for ertapenem, and 49.47% for imipenem. Based on the results of the double-disk synergy test, 93 out of 190 (48.95%) K. pneumoniae isolates were extended-spectrum beta-lactamase. In conclusion, PMF is a powerful analytical technique used to identify K. pneumoniae isolates from clinical samples based on their proteomic characteristics. K. pneumoniae isolates have shown increasing resistance to antibiotics from different classes, including carbapenem, which poses a significant threat to human health as these infections may become difficult to treat.

Camel urine as a potential source of bioactive molecules showing their efficacy against pathogens: A systematic review

Camels are highly suited for severe desert conditions and able to provide most of the natural products like urine, which has been used as alternative medicine to treat diverse infections and disorders. There is, however, a shortage and paucity of scientific reviews highlighting the antifungal, antibacterial and antiviral effects of camel urine. By better understanding its antimicrobial characteristics, our overarching aim is to provide an exhaustive overview of this valuable natural product by synthesizing and summarizing data on the efficacy of this biofluid and also describing the potential substances exhibiting antimicrobial properties. We searched three databases in order to point out relevant articles (Web of Science, Scopus and Google Scholar) until December 2022. Research articles of interest evaluating the antimicrobial effects of camel urine were selected. Overall, camel urine furnished promising antibacterial activities against gram-positive bacteria, namely Staphylococcus aureus (30 mm), Bacillus cereus (22 mm), Bacillus subtilis (25 mm) and Micrococcus luteus (21 mm), as well as gram-negative bacteria, especially Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter cloacae, and Salmonella spp., without forgetting its efficiency on Mycobacterium tuberculosis as well. The excretion also showed its potency against H1N1 virus, vesicular stomatitis virus and middle east respiratory syndrome coronavirus. Similarly, the camel urine featured strong antifungal activity against Candida albicans, Aspergillus niger, Aspergillus flavus and dermatophytes with a minimal inhibitory concentration of 0.625 μg/ml against Trichophyton violaceum, 2.5 μg/ml against Microsporum canis and 1.25 μg/ml against Trichophyton rubrum and Trichophyton mentagrophytes. This comprehensive review will be valuable for researchers interested in investigating the potential of camel urine in the development of novel broad-spectrum key molecules targeting a wide range of drug-resistant pathogenic microorganisms.

Contamination of Kazakhstan cheeses originating from Escherichia coli and its resistance to antimicrobial drugs

Background and Aim

Escherichia coli, a commensal intestine bacterium of vertebrates, is widely distributed in the environment and indicates the microbiological quality of food products in relation to coliforms. In addition, virulent strains, particularly E. coli O157:H7, cause outbreaks of toxic infections caused by consuming dairy products. Because food safety studies regarding E. coli have not been conducted in Central Asia, this research aimed to study the characteristics of contamination, microbiological and genotypic properties, and resistance to antimicrobial agents of E. coli strains that contaminate various types of commercialized cheeses originating from Kazakhstan.

Materials and Methods

In retail outlets, 207 samples of three types of cheese produced by 22 industrial and eight small enterprises in the central, eastern, southern, and northern regions of Kazakhstan were selected in 2020-2023. E. coli contamination was examined using standard microbiological, mass spectrometric, and molecular genetic methods. The discodiffuse European Committee on Antimicrobial Susceptibility Testing method was used to test the resistance of the identified E. coli isolates (65/207; 31.4%) to 20 antibacterial drugs. The Shiga toxin-producing E. coli (VT1 and VT2) and E. coli O157:H7 (eae) genes were investigated in all E. coli isolates using multiplex polymerase chain reaction.

Results

An average of 31.4% samples of commercial Kazakhstani cheeses of various types were found to be contaminated with E. coli in almost all geographical regions of Kazakhstan, regardless of the productivity of the dairy enterprises. Soft cheeses produced by small farms (80% of samples) packaged at the retail site (100%) were the most contaminated with E. coli. The microbiological index (colony-forming unit/g) was unsatisfactory and unsuitable in 6.2% of such cheese samples. For the first time in Central Asia, the enteropathogenic strain E. coli O157:H7 was detected in 0.5% of cheese samples. E. coli isolates from cheese samples were resistant to 65% of antibacterial drugs and contained resistance genes to β-lactams, sulfonamides, and quinolones groups. At the same time, 25% of the E. coli isolates were multi-resistant to three or more antimicrobial agents.

Conclusion

The high level of contamination caused by multi-antibiotic resistant E. coli strains, including pathogenic pathogens, poses a risk to public health and highlights the need for further research on the monitoring and control of coliform enteropathogens in food products.

The Development of Diagnostic and Vaccine Strategies for Early Detection and Control of Human Brucellosis, Particularly in Endemic Areas

Brucellosis is considered one of the most serious zoonotic diseases worldwide. This disease affects both human and animal health, in addition to being one of the most widespread zoonotic illnesses in the Middle East and Northern Africa. Human brucellosis generally presents in a diverse and non-specific manner, making laboratory confirmation of the diagnosis critical to the patient's recovery. A coordinated strategy for diagnosing and controlling brucellosis throughout the Middle East is required, as this disease cannot be known to occur without reliable microbiological, molecular, and epidemiological evidence. Consequently, the current review focuses on the current and emerging microbiological diagnostic tools for the early detection and control of human brucellosis. Laboratory assays such as culturing, serology, and molecular analysis can frequently be used to diagnose brucellosis. Although serological markers and nucleic acid amplification techniques are extremely sensitive, and extensive experience has been gained with these techniques in the laboratory diagnosis of brucellosis, a culture is still considered to be the "gold standard" due to the importance of this aspect of public health and clinical care. In endemic regions, however, serological tests remain the primary method of diagnosis due to their low cost, user-friendliness, and strong ability to provide a negative prediction, so they are commonly used. A nucleic acid amplification assay, which is highly sensitive, specific, and safe, is capable of enabling rapid disease diagnosis. Patients who have reportedly fully healed may continue to have positive molecular test results for a long time. Therefore, cultures and serological methods will continue to be the main tools for diagnosing and following up on human brucellosis for as long as no commercial tests or studies demonstrate adequate interlaboratory reproducibility. As there is no approved vaccine that prevents human brucellosis, vaccination-based control of animal brucellosis has become an important part of the management of human brucellosis. Over the past few decades, several studies have been conducted to develop Brucella vaccines, but the problem of controlling brucellosis in both humans and animals remains challenging. Therefore, this review also aims to present an updated overview of the different types of brucellosis vaccines that are currently available.

Camel (Camelus spp.) Urine Bioactivity and Metabolome: A Systematic Review of Knowledge Gaps, Advances, and Directions for Future Research

Up to the present day, studies on the therapeutic properties of camel (Camelus spp.) urine and the detailed characterization of its metabolomic profile are scarce and often unrelated. Information on inter individual variability is noticeably limited, and there is a wide divergence across studies regarding the methods for sample storage, pre-processing, and extract derivatization for metabolomic analysis. Additionally, medium osmolarity is not experimentally adjusted prior to bioactivity assays. In this scenario, the methodological standardization and interdisciplinary approach of such processes will strengthen the interpretation, repeatability, and replicability of the empirical results on the compounds with bioactive properties present in camel urine. Furthermore, sample enlargement would also permit the evaluation of camel urine's intra- and interindividual variability in terms of chemical composition, bioactive effects, and efficacy, while it may also permit researchers to discriminate potential animal-intrinsic and extrinsic conditioning factors. Altogether, the results would help to evaluate the role of camel urine as a natural source for the identification and extraction of specific novel bioactive substances that may deserve isolated chemical and pharmacognostic investigations through preclinical tests to determine their biological activity and the suitability of their safety profile for their potential inclusion in therapeutic formulas for improving human and animal health.

Occurrence, Pathogenic Potential and Antimicrobial Resistance of Escherichia coli Isolated from Raw Milk Cheese Commercialized in Banat Region, Romania

The aim of the present study was to investigate the presence, pathogenic potential and antimicrobial susceptibility profile of Escherichia coli isolated from raw milk cheese, traditionally produced by farmers and marketed directly to the consumer in Banat region, Romania. A total of 81.1% (43/53) of the processed samples expressed positive results for E. coli, with a distribution of 83.8% (31/37), and 75.0% (12/16) in the cow- and sheep-milk-origin assortments, respectively. Overall, 69.8% (30/43) of the specimens had a contamination level ≤10 CFU/g. Molecular tests showed that, from the total number of E. coli isolates, 9.3% (4/43) harbored the stx2, and 2.3% (1/43), the stx1 virulence genes. The E. coli O157 (including H7) biovariety was identified in 7% (3/43) of the samples by the Vidas equipment. From the 27 antimicrobials tested with the Vitek2 automated system, the E. coli isolates displayed resistance to enrofloxacin (100%, 15 out of 15 tested isolates), ampicillin (39.5%, 17/43), norfloxacin (28.6%, 8/28), fosfomycin (25%, 7/28), amoxicillin/clavulanic acid (23.3%, 10/43), cefalexin (20%, 3/15), cefalotin (13.3%, 2/15), tetracycline (13.3%, 2/15), trimethoprim-sulfamethoxazole (9.3%, 4/43), piperacillin-tazobactam (7.1%, 2/28), cefotaxime (7.1%, 2/28), cefepime (7.1%, 2/28), ticarcillin/clavulanic acid (6.7%, 1/15), florfenicol (6.7%, 1/15), ceftazidime (3.6%, 1/28), and ertapenem (3.6%, 1/28). Ten (23.3%) strains were multidrug-resistant. The obtained preliminary results indicated hygienic–sanitary deficiencies throughout the cheese production process, and demonstrated that these products can harbor virulent and multidrug-resistant E. coli strains, which constitute a public health risk. However, future investigations, processing a higher number of samples, are still necessary to draw comprehensive conclusions.

Characterization of Antibiotic Resistant Coliform Bacteria and Resistance Genes Isolated from Samples of Smoothie Drinks and Raw Milk

Raw foodstuffs have been marked as a healthier alternative in the context of nutrient content and are becoming more popular with consumers. Thermally untreated foods may represent a microbiological risk connected with the possible presence of antimicrobial resistance. The aim of this study was to prove that popular raw food beverages such as smoothies and raw milk may be a source of antibiotic-resistant coliform bacteria and resistant genes. The majority of antibiotic-resistant isolates (110) were identified as Enterobacter spp., Escherichia coli, and species of Klebsiella spp., predominantly β-lactam and chloramphenicol resistant. Multidrug resistance has been registered in one-third of resistants. Overproduction of efflux pumps was clarified in 8 different bacteria. The majority of resistant isolates were strong biofilm producers. Antibiotic resistance gene blaOXA was detected in 25% of isolates, especially in E. coli. Resistance genes blaTEM and blaSHV were detected in 19% and 14%, respectively. This is the first study to point out that popular raw drinks such as smoothies or raw milk, besides their nutrient benefits, could represent a reservoir of antibiotic-resistant bacteria as well as antibiotic resistance genes. According to this, raw drinks could contribute to the dissemination of antibiotic resistance in the human gastrointestinal tract and environment.

Proteomics-based screening and antibiotic resistance assessment of clinical and sub-clinical Brucella species: An evolution of brucellosis infection control

Brucellae are intracellular sneaky bacteria and they can elude the host's defensive mechanisms, resulting in therapeutic failure. Therefore, the goal of this investigation was to rapid identification of Brucella species collected from animals and humans in Saudi Arabia, as well as to evaluate their resistance to antibiotics. On selective media, 364 animal samples as well as 70 human blood samples were cultured. Serological and biochemical approaches were initially used to identify a total of 25 probable cultured isolates. The proteomics of Brucella species were identified using the MALDI Biotyper (MBT) system, which was subsequently verified using real-time polymerase chain reaction (real-time PCR) and microfluidic electrophoresis assays. Both Brucella melitensis (B. melitensis) and Brucella abortus (B. abortus) were tested for antimicrobial susceptibility using Kirby Bauer method and the E-test. In total, 25 samples were positive for Brucella and included 11 B. melitensis and 14 B. abortus isolates. Twenty-two out of 25 (88%) and 24/25 (96%) of Brucella strains were recognized through the Vitek 2 Compact system. While MBT was magnificently identified 100% of the strains at the species level with a score value more than or equal to 2.00. Trimethoprim-sulfamethoxazole, rifampin, ampicillin-sulbactam, and ampicillin resistance in B. melitensis was 36.36%, 31.82%, 27.27%, and 22.70%, respectively. Rifampin, trimethoprim-sulfamethoxazole, ampicillin, and ampicillin-sulbactam resistance was found in 35.71%, 32.14%, 32.14%, and 28.57% of B. abortus isolates, correspondingly. MBT confirmed by microfluidic electrophoresis is a successful approach for identifying Brucella species at the species level. The resistance of B. melitensis and B. abortus to various antibiotics should be investigated in future studies.