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May 2023 DOI 10.14302/issn.2575-1212.jvhc-23-4521
El- shaer AyaCorresponding author
Background The emergence and spread of carbapenem-resistant gram-negative bacteria pose a serious threat to human health. Currently, little is known about the molecular mechanisms underlying carbapenem -resistance and their prevalence among APEC in Egypt. The aim of this study was to detect APEC in clinically diseased broiler chickens collected from broilers farms located at Dakahalia governorates, asses their virulence –associated genes, detect the antimicrobial susceptibility of recovered isolates and to detect genes encoding carbapenemase resistant. Methods A total of 100 organ tissue samples subjected to conventional culture technique for isolation of E. coli. The confirmed E. coli were subjected to disc diffusion method for detection their susceptibility to antimicrobials. Polymerase chain reaction (PCR) was used for detection of APEC virulence genes (hlyA, iutA, ompT, iss, iroN) and six carbapenem- resistant genes namely, blaIMP, blaVIM, blaKPC, blaOXA-48 blaGES and blaNDM,. Results Forty isolates were confirmed to be E. coli among them, three or more APEC virulence- genes were detected from all isolates. The hlyA gene was detected in 90% (36/40), iroN in 95% (38/40), ompT in 97.5% (39/40), iutA in 92.5% (35/40) and iss was detected in 95% (38/40) of APEC isolates The tested isolates exhibited a remarkable resistance to ampicillin (97.5%), cefuroxime (92.5%), clindamycin (90%), chloramphenicol (62.5%), doxycycline (45%), amikacin (25%) and ciprofloxacin (12.5%). While, the retrieved isolates displayed 100 % sensitivity against imipenem, meropenem, ertapenem, ceftazidime and colistin. Concerning carbapenemase-encoding genes, blaIMP, blaVIM, blaKPC, blaOXA-48, blaGES couldn’t be detected among the E. coli isolates, while, blaNDM was confirmed in three isolates . Conclusion The detection of NDM as one of the carbapenem resistant genes reveals that the resistant strains are not only capable of infecting humans, but that carbapenams- resistant E. coli (CREC) has also started to pose a threat to poultry farm and other livestock animals. This may give rise to worries that these food-carrying creatures could infect humans or colonize them.
Mar 2021 DOI 10.14302/issn.2575-1212.jvhc-21-3767
Abdishakur Hassan FaysalCorresponding author
Advanced Scientific Group, Abu Dhabi, United Arab Emirates
Antibodies and antibody fragments, especially single-domain antibodies known as nanobodies, are important tools in diagnostics, research, and therapeutics. In a conventional antibody, light and heavy chains contribute to the formation of the antigen binding site. In addition to conventional antibodies, old and new world camels also have heavy-chain antibodies (hcAbs), which lack the light-chain antibodies that usually bind to the antigen, as well as single domain antibodies, the VHH domain, which are the smallest antigen-binding fragments and have high solubility, stability, and specificity. A VHH library against E. coli lipopolysaccharide (LPS) was produced using the camel immune system. E. coli strains from dead camel calves were isolated to extract the LPS and used to immunize a 2-year-old female camel. After isolating mononuclear lymphocytes for RNA extraction and amplification of the VHH gene, the PCR product was cloned into the pF1AT7 Flexi vector and transformed into JM109 E. coli competent cells by heat shock, resulting in a comprehensive VHHs library with 6.9 × 104 cfu/µg. The VHHs were expressed and screened with ELISA and PCR. Eleven colonies were positive by PCR, six of which were sequenced and submitted to Genbank compared with GenBank data to confirm the production of nanobodies with a similarity >90%.
Jul 2025 DOI 10.14302/issn.2769-2264.jw-25-5578
Nyamaizi SylviaCorresponding author
Wetland encroachment due to agricultural land use practices (LUPs) adversely affects water quality in wetlands mainly through agricultural runoff. This study was conducted in Lubigi wetland in Uganda to (1) determine the effect of the agricultural LUPs on water quality and (2) understand the relationships between different water quality indicators and different agricultural LUPs existing in the wetland. The eight LUPs included in this study were perennial crops i.e. banana farming and sugarcane farming, annual crops i.e. maize farming and tomato farming, livestock farming which included a mixture of cows, goats, and sheep, undisturbed dense natural vegetation, reference wetland and the river. Water samples collected from the different LUPs were analyzed in the laboratory for selected physicochemical and biological water quality parameters. The water samples were analyzed for a variety of properties, including pH, electrical conductivity, total hardness, Ca-hardness, Mg- hardness, and concentrations of dissolved oxygen, calcium, magnesium, fluoride, total nitrogen, nitrates, ammonium, phosphates, potassium, total coliform, and Escherichia coli (E. coli), chemical oxygen demand, biological oxygen demand, total organic carbon, total dissolved solids, chlorides, sulphates, total phosphorus, and turbidity levels. The results suggested that the different LUPs influenced several water quality parameters. Dissolved oxygen was lowest in banana fields and the river at 2.57 mg/L and 3.44 mg/L respectively than other LUPs which limits survival of aquatic organisms. Biological oxygen demand, chemical oxygen demand and total organic carbon were high in the river water with values = 69.67 mg/L, 351.67 mg/L, 117.33 mg/L respectively indicating high organic pollution. We detected nutrient pollution in water from tomato and sugarcane fields which showed high concentrations of nitrates. The concentration of ammonium in river water (10.40 mg/L) was high, indicating nitrogen contamination. In all LUPs, Escherichia coli and total coliforms had high counts exceeding 2000 CFU/100mL which indicated elevated microbial pollution from livestock waste and agricultural runoff. Cluster analysis revealed distinct clusters influenced by varying water quality parameters. These findings show that agricultural LUPs in Lubigi wetland are significantly contributing to water pollution through microbial contamination, nutrient, and organic matter accumulation, which increases the potential for eutrophication and renders the water unsafe for drinking and domestic use. Implementing best management practices (BMPs) is essential for the sustainable use and management of the wetland.
Feb 2023 DOI 10.14302/issn.2576-6694.jbbs-22-4418
Mostafa M. Sabra SherifaCorresponding author
Saudi Arabia is rich in Juniperusprocera Hochst. ex Endl (Cupressaceae) as a medicinal plant. Its known as Arar, its present southwards, KSA. It's used as traditional medicine in the southwestern, KSA. The aim was according to "Saudi Arabian Customs" in using wild-plant extract for treatment and prevention of infectious-pathogens. That was to use Juniperusprocerafrom Ranyah, KSA to eliminate infectious-pathogens that were isolated from patients in the same area. This was the use may reduce the use of chemicals, as well it may be an alternative to chemotherapy. Practice included preparation of wild-plant extract, preparation of infectious-pathogens, interaction to wild-plant extract, and direct total cell count by "Bread Test". Juniperusprocera one crude concentration killed all infectious-pathogens during one day. Lower Juniperusprocera crude extract concentrations eliminated infectious-pathogens within more than one day. The mean number of dead sells / mL of Staphylococcus sp., Streptococcus sp, and Streptococcus pyogenes were (84.9 / mL, 87.0 / mL, and 77.8 / mL). The mean percent of dead cells were (80.0%, 82.0%, and 73.4%). The meannumber of dead sells / mL of Salmonella sp., Shigella sp, and Escherichia coli were (72.6 / mL, 76.1 / mL, and 79.0 / mL). The mean percent of dead cells were (68.5%, 71.8%, and 74.5%). The mean number of Candida albicans dead sells / mL was 69.3 / mL, the mean percent of dead cells was 65.4%. It was concluded that found from the results, the Juniperusprocera extract was preferred "Saudi Arabian Customs" to be used in three quarter and one crude concentration, as the infectious-pathogens eliminating within one day. It was recommended that the Juniperusprocera extract will be used for herbal treatment according to "Saudi Arabian Customs". That will be remark and follow-up through the "Official Herbal Treatment Dept.". That will appropriate the doses will estimate for each patient to eliminate and protect against the infectious-pathogens.
Jun 2021 DOI 10.14302/issn.2474-3585.jpmc-21-3851
A. Njukeng PatrickCorresponding author
Global Health Systems Solutions, Douala, Cameroon
Background The rapid and ongoing spread of antimicrobial-resistant organisms threatens the ability to successfully prevent, control, or treat a growing number of infectious diseases in developed and developing countries. This study was designed to convey more insight on the profile of antimicrobial resistance and the capacity of laboratories conducting antimicrobial susceptibility testing in Cameroon. Methods A multicentre cross-sectional study was conducted from October 2019 to March 2020 in the Deido Health District. Laboratories that carry out culture and sensitivity testing within the Deido Health District were identified and assessed to determine their capacity as well as the quality of results from microbiological investigations. Information on antimicrobial susceptibility of various isolates was collected using tablet phones in which the study questionnaires had been incorporated. Results Gaps identified in antimicrobial susceptibility testing that cut across laboratories included; insufficient standard operating procedures, inadequate records on personnel training and competency assessment, lack of safety equipment such as biosafety cabinet, stock out and non-participation in external quality assurance program. The turnaround time for antimicrobial susceptibility testing ranged from 3 – 7 days. Out of the 1797 samples cultured, 437(24.3%) had at least one isolate. A total of 15 different isolates were identified with Candida albicans being the most frequent 178 (40.7%), followed by Escherichia coli 80(18.3%). Among the 15 classes of antimicrobial drugs used in this study, the overall resistance of the isolates showed that five classes had class median resistance above 40% (Cephalosporins, Penicillins, Beta-lactam, Macrolides, and Polyenes). Conclusion This study has shown the need to develop a coordinated national approach to fight antimicrobial resistance. Scaling-up of antimicrobial susceptibility testing will, therefore, require strengthening the microbiology units of laboratory systems as well as ensuring the use of laboratory data for decision making.
Jan 2019 DOI 10.14302/issn.2328-0182.japst-18-2495
Obioma AzuonwuCorresponding author
Department of Medical Laboratory Science, Medical Bacteriology / Virology / Parasitology Unit, Rivers State University, Nkpolu – Oroworukwo, Port Harcourt, Nigeria.
Over the years, plants have been a major source of medicines, especially in the rural areas of the developing communities, with probably lack of functional health care facilities and trained health care personnel on hand for emergency medical response. However, with the dynamics and improvement in science and medicine, chemically synthesized drugs were being introduced and used to treat myriad of critical illnesses across board. Nonetheless, these were further strengthened owing to the increasing trend of drug resistance outcome, especially by the emerging and re-emerging infectious microorganisms. Thus, in the light of the above, there is a gradual but increasing steady return to the use of plants as sources of medicine and treatment of antibiotic resistance pathogens and illness across the globe. This study therefore, explores the use of antimicrobial activity of the leaves, stembark and root of Allanblackia floribunda on four bacterial isolates namely Staphylococcus aureus, Escherichia coli, Pseudomonas sp. and Bacillus sp. Methylated spirit, ethanol and distilled water were used as the extraction solvents differently. Ethanol extracts proved to be a better solvent compared with the other two while the extracts from distilled water were not active against any of the isolates. However, all the three ethanol extracts were more active against S. aureus while Pseudomonas sp. showed a higher level of resistance to the extracts. The leaves and root of the plant were more active on most of the isolates compared with the stembark as shown in the results section.
May 2018
Ahsan Naeem MuhammadCorresponding author
College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, P.R. China.
Microorganisms are the main cause of food-borne illness in humans that may occur by consuming unhygienic products from poultry and other sources. With the passage of time bacterial resistance to antibiotics is ever-increasing which necessitates development of new antibiotics. One of the most obvious reasons of antimicrobial resistance in human-beings is the consumption of contaminated food with microbes. The aim of present study is to isolate, identify and characterize the food-borne pathogens from chicken eggs. For this purpose, a total of 240 egg samples were collected from eight different towns of Faisalabad. Samples were collected from egg surface, yolk, albumin and egg tray. Isolation, identification and characterization of commonly occurring egg borne pathogens including E. coli, Salmonella spp., Bacillus subtilis, Staphylococcus aureus were carried out by different cultural, morphological and biochemical tests. Antibiotic resistance pattern of recovered bacterial pathogens was determined by disk diffusion method (Kirby-Bauer). Zone of inhibition was measured through vernier calliper. The results revealed a high prevalence of Salmonella entitidis with 40.83% following Staphylococcus aureus with 22.08%, Escherichia coli with 17.92% and Bacillus subtilis in a lower ratio with 2.5%. The antibiotic sensitivity test showed different resistance patterns of the isolated microbes. For this purpose, five different drugs were used that included cefotaxime, tetracycline, gentamicin, levofloxacin and penicillin. Bacillus subtilis was highly resistant to penicillin and cefotaxime. Whereas, E. coli showed resistance to three antibiotics that were tetracycline, cefotaxime and penicillin. The only drug to which Staphylococcus aureus showed resistance was cefotaxime. Salmonella was resistant to tetracycline and gentamicin. The study concluded that chicken egg is contaminated with a number of bacteria that could be pathogenic or not. So, there is need of proper attention to cope up with possible future egg-borne illnesses.