Characterization of Multiple Resistance Genes of Escherichia coli Strains Isolated from Food and Clinical Samples.

Multi-drug resistance (MDR), which is formed by the development of antimicrobial resistance, which is one of the defense mechanisms in bacteria, has pushed human beings to constantly seek new antimicrobial agents in the fight against these microorganisms. Speed and precision are very important in identifying resistance in strains with MDR that reach humans in an open system through the consumption of contaminated food or water. The main aim of this study was the molecular characterization of ESBL gene variants (blaTEM, blaOXA, blaSHV, and blaCTX-M), integron genes (int1, int2, and int3), and sulphonamide (sul1, sul2, and sul3) resistance genes by PCR from E. coli isolates originated from food and clinical samples. A total of 17 sets of primers were used for phylogenetic identification, molecular detection, and resistance and integron gene characterization of phenotypically identified E. coli isolates. The 45 red meat samples were collected from local markets, which are located in four (Adiyaman, Gaziantep, Kahramanmaras, and Hatay) different provinces, clinical isolates were obtained from urine samples of patients with UTI from Sanliurfa Mehmet Akif Inan Training and Research Hospital. Three gene groups were screened with 3 multiplex PCR applications in 63 food and 33 clinical isolates found to be E. coli by molecular identification. In terms of the 3 gene groups screened in food samples, the highest rates were found in the blaSHV gene at 44.44%, the sul1 gene at 69.84% and the int2 gene at 73.02%; in clinical samples, it is listed as blaCTX-M gene at 15.15%, sul2 gene at 81.82% and int1 gene at 54.55%. In terms of 3 gene groups scanned, the presence of 3 or more genes, including at least one gene from each gene group, was detected in 31 isolates from food samples and 2 isolates from clinical samples. Overall, it can be said that the high frequency of MDR genes isolated from E. coli-contaminated red meat samples and clinical samples gives a clue about the overuse of antibiotics in Türkiye.

Genotoxic and mutagenic studies of teratogens in developing rat and mouse.

In this review, genotoxic and mutagenic effects of teratogenic chemical agents in both rat and mouse have been reviewed. Of these chemicals, 97 are drugs and 33 are pesticides or belong to other groups. Large literature searches were conducted to determine the effects of chemicals on chromosome abnormalities, sister chromatid exchanges, and micronucleus formation in experimental animals such as rats and mice. In addition, studies that include unscheduled DNA synthesis, DNA adduct formations, and gene mutations, which help to determine the genotoxicity or mutagenicity of chemicals, have been reviewed. It has been estimated that 46.87% of teratogenic drugs and 48.48% of teratogenic pesticides are positive in all tests. So, all of the teratogens involved in this group have genotoxic and mutagenic effects. On the other hand, 36.45% of the drugs and 21.21% of the pesticides have been found to give negative results in at least one test, with the majority of the tests giving positive results. However, only 4.16% of the drugs and 18.18% of the pesticides were determined to give negative results in the majority of the tests. Among tests with major negative results, 12.50% of the teratogenic drugs and 12.12% of the teratogenic pesticides were negative in all conducted tests.

Molecular identification of common Salmonella serovars using multiplex DNA sensor-based suspension array.

Salmonella is one of major foodborne pathogens and the leading cause of foodborne illness-related hospitalizations and deaths. It is critical to develop a sensitive and rapid detection assay that can identify Salmonella to ensure food safety. In this study, a DNA sensor-based suspension array system of high multiplexing ability was developed to identify eight Salmonella serovars commonly associated with foodborne outbreaks to the serotype level. Each DNA sensor was prepared by activating pre-encoded microspheres with oligonucleotide probes that are targeting virulence genes and serovar-specific regions. The mixture of 12 different types of DNA sensors were loaded into a 96-well microplate and used as a 12-plex DNA sensor array platform. DNA isolated from Salmonella was amplified by multiplex polymerase chain reaction (mPCR), and the presence of Salmonella was determined by reading fluorescent signals from hybridization between probes on DNA sensors and fluorescently labeled target DNA using the Bio-Plex® system. The developed multiplex array was able to detect synthetic DNA at the concentration as low as 100 fM and various Salmonella serovars as low as 100 CFU/mL within 1 h post-PCR. Sensitivity of this assay was further improved to 1 CFU/mL with 6-h enrichment. The array system also correctly and specifically identified serotype of tested Salmonella strains without any cross-reactivity with other common foodborne pathogens. Our results indicate the developed DNA sensor suspension array can be a rapid and reliable high-throughput method for simultaneous detection and molecular identification of common Salmonella serotypes.

Effect of HOTAIR rs12826786 and rs1899663 polymorphisms on lung cancer susceptibility and clinicopathological characteristics in a turkish population: a hospital-based case-control study.

Overexpression of Hox transcript antisense intergenic RNA (HOTAIR), a long non-coding RNA (lncRNA), is associated with tumorigenesis and multiple cancer types including lung cancer. In this study, the association between two HOTAIR single nucleotide polymorphisms (SNPs) (rs12826786 and rs1899663) on the risk and clinical characteristics of lung cancer in a Turkish population was investigated. We genotyped HOTAIR rs12826786 and rs1899663 polymorphisms in 180 Turkish people including 87 lung cancer patients (71 males and 16 females) and 93 age-matched healthy controls (67 males and 26 females) by a TaqMan real-time polymerase chain reaction method. The mean age value of the lung cancer patients and control subjects were 59.27 ± 10.55 and 61.77 ± 12.00, respectively. We found that none of the two HOTAIR polymorphisms (rs12826786 T>C, rs1899663A>C) has any significant association with the increased risk of lung cancer in any type of inheritance genetic models. However, our research indicated that carriers of Trs12826786/Crs1899663 (ht3) (P = 0.03) had an increased risk of lung cancer susceptibility.

Genetic polymorphisms in human telomerase reverse transcriptase (hTERT) gene polymorphisms do not associated with breast cancer in patients in a turkish population: hospital-based case-control study.

Breast cancer (BC) is encountered most frequently in developed or developing countries. It is the most common cancer in humans following lung cancer, and it is the most common cancer type resulting in mortality in women. Genetic polymorphisms are among the genetic factors that play an important role in the development of the breast cancer. The purpose of this study was to investigate the effect of five functional single nucleotide polymorphisms (SNPs) of hTERT (rs2736109 G>A, rs2735940 T>C, rs2853669 A>G, rs2736098 G>A, and rs2736100 T>G) on susceptibility to BC in Turkish population. The genotype frequency of hTERT rs2736109 G>A, rs2735940 T>C, rs2853669 A>G, rs2736098 G>A, and rs2736100 T>G polymorphisms were determined by using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and TaqMan methods in 123 subjects with GC and 122 healthy control subjects. The mean age value of the BC patients was 51.58±11.28 (among them 8 subjects ≤35 and 115 subjects >35). In this study, it was found that there was no statistical difference between hTERT rs2736109 G>A, rs2735940 T>C, rs2853669 A>G, rs2736098 G>A, and rs2736100 T>G polymorphisms that can be associated with risk of BC.

The relationship between the variations in Gγ and Aγ promotors and the Hereditary Persistence of Fetal Hemoglobin (HPFH).

In the present study, sixty-two samples that have 1.5% and upper level of fetal hemoglobin (HbF), were examined to investigate the relationship between HbF level and non-deletional mutations in both Gγ (G gamma) globin (HBG2) and Aγ (A gamma) globin (HBG1) genes. Four variations were observed in the promotor of Gγ gene, which are -158C/T, -309A/G, -369C/G, and -567T/G. Also, four variations were observed in the 5'-UTR (untranslated regions) and promotor of Aγ gene, which are +25G/A, -369G/C, -499T/A, and -588G/A. One -222/-225 AGCA del homozygous and six variations as heterozygous in A gamma globin gene promotor region were also observed. The results of the current study suggested that there was a significant relationship between high HbF levels and two variations (-309A/T and -369C/G) in Gγ gene promotor. Additionally, a significant relationship between two variations (+25G/A and -499T/A) in Aγ gene promotor was also observed. Furthermore, the persons who carry these variations with high levels of HbF indicated that there might be a haplotype effect between these variations.

Characterization of extended spectrum ß-lactamase (ESBL)-producing Escherichia coli in Asi (Orontes) River in Turkey.

In this study, the presence of extended spectrum ß-lactamase (ESBL)-producing Escherichia coli in aquatic environments (the Orontes River and an urban wastewater) was investigated. Fifty-four E. coli strains resistant to cefotaxime were isolated from the river waters and nearby waste water treatment plant and screened for ESBL gene variants, different classes of integrons and sulfonamide resistance genes. The ESBL-producing E. coli strains were further characterized by PhP-typing system, phylogenetic grouping and antimicrobial susceptibility testing. Of the 54 ESBL-producing strains, 14 (25.9%) belonged to four common PhP types and the remaining were of single types. CTX-M type ESBL genes were identified in 68% of the isolates. The most predominant specific CTX-M subtype identified was blaCTX-M-15 (n = 36), followed by blaCTX-M-1 (n = 1). None of the isolates were SHV and OXA positive. Most of the ESBL positive isolates (n = 37; 68.5%) were harboring sul gene. This study indicates a widespread distribution of CTX-M-15 producing E. coli strains in the surface waters in part of Turkey, suggesting an aquatic reservoir for ESBL genes.

Current and emerging technologies for rapid detection and characterization of Salmonella in poultry and poultry products.

Salmonella is the leading cause of foodborne illnesses in the United States, and one of the main contributors to salmonellosis is the consumption of contaminated poultry and poultry products. Since deleterious effects of Salmonella on public health and the economy continue to occur, there is an ongoing need to develop more advanced detection methods that can identify Salmonella accurately and rapidly in foods before they reach consumers. Rapid detection and identification methods for Salmonella are considered to be an important component of strategies designed to prevent poultry and poultry product-associated illnesses. In the past three decades, there have been increasing efforts towards developing and improving rapid pathogen detection and characterization methodologies for application to poultry and poultry products. In this review, we discuss molecular methods for detection, identification and genetic characterization of Salmonella associated with poultry and poultry products. In addition, the advantages and disadvantages of the established and emerging rapid detection and characterization methods are addressed for Salmonella in poultry and poultry products. The methods with potential application to the industry are highlighted in this review.

The Future of the Teratogenicity Testing.

The purpose of this review is to examine the importance, possible advantages and disadvantages of teratogenicity tests, and their future. For this purpose, numerous sources have been scanned in the field of teratogenicity. Although there are many methods related to teratogenic studies and very important studies have been made in this field, there are still serious deficiencies. There are advantages and disadvantages of in vitro and in vivo classical tests that have been used so far. The current status of in vivo tests is a matter of debate, especially due to the use of experimental animals. However, in vitro tests that do not perform the distribution and metabolism of chemicals also raise doubts in determination of teratogenicity. Despite the modern approaches of molecular biology and genetics and the best diagnostic techniques, the real cause of more than half of congenital diseases is still not understood. In this sense, the importance and necessity of teratogenic tests are understood once again. It is necessary to develop faster, reliable, and inexpensive techniques to replace traditional in vivo tests. It is important to disseminate harmless and reliable imaging techniques such as micro-CT. The use of European Center for the Validation of Alternative Methods (ECVAM) scientifically validated and approved in vitro tests such as embryonic stem cell test (EST), micro mass test (MM), and whole embryo culture (WEC) tests in routine screening can provide a solution in a shorter time than the classical tests. Improving these tests and developing new tests can help to solve the problem permanently.

Methodology of Genotoxic and Teratogenic Studies in Rats.

The genotoxicity methods applied to rats are tests that can detect any damage, including changes in the number of chromosomes or in the structure of chromosomes, and nucleotide changes with structural abnormality in the DNA of animal cells. However, the method of teratogenicity is used to detect the effects of chemicals which cause congenital defects in living organisms. This study contains information about the effectiveness, reliability, ways of application, and methodology of genotoxic and teratogenic methods applied in vivo in rats.

Rapid and sensitive detection of Escherichia coli O157:H7 in milk and ground beef using magnetic bead-based immunoassay coupled with tyramide signal amplification.

Escherichia coli O157:H7 is a major foodborne pathogen that has posed serious problems for food safety and public health. Recent outbreaks and recalls associated with various foods contaminated by E. coli O157:H7 clearly indicate its deleterious effect on food safety. A rapid and sensitive detection assay is needed for this harmful organism to prevent foodborne illnesses and control outbreaks in a timely manner. We developed a magnetic bead-based immunoassay for detection of E. coli O157:H7 (the most well-known Shiga toxigenic E. coli strain) with a 96-well microplate as an assay platform. Immunomagnetic separation (IMS) and tyramide signal amplification were coupled to the assay to increase its sensitivity and specificity. This immunoassay was able to detect E. coli O157:H7 in pure culture with a detection limit of 50 CFU/ml in less than 3 h without an enrichment step. The detection limit was decreased 10-fold to 5 CFU/ml with addition of a 3-h enrichment step. When this assay was tested with other nontarget foodborne pathogens and common enteric bacteria, no cross-reactivity was found. When tested with artificially contaminated ground beef and milk samples, the assay sensitivity decreased two- to fivefold, with detection limits of 250 and 100 CFU/ml, respectively, probably because of the food matrix effect. The assay results also were compared with those of a sandwich-type enzyme-linked immunosorbent assay (ELISA) and an ELISA coupled with IMS; the developed assay was 25 times and 4 times more sensitive than the standard ELISA and the IMS-ELISA, respectively. Tyramide signal amplification combined with IMS can improve sensitivity and specificity for detection of E. coli O157:H7. The developed assay could be easily adapted for other foodborne pathogens and will contribute to improved food safety and public health.

Preventive effect of rolipram, a phosphodiesterase 4 enzyme inhibitor, on oxidative renal injury in acute ascending pyelonephritis model in rats.

OBJECTIVES: To evaluate the effects of rolipram, a phosphodiesterase 4 enzyme inhibitor, on Escherichia coli-induced renal oxidative damage in an acute pyelonephritis (PYN) rat model. METHODS: A total of 35 male Wistar albino rats were randomly divided into 7 groups (n = 5) as follows: control (uninfected), PYN 24 hours, PYN 48 hours, PYN 72 hours, PYN + rolipram 24 hours, PYN + rolipram 48 hours, and PYN + rolipram 72 hours. Ascending PYN was induced in the study groups by E. coli inoculation into the bladder, and the urethras were then occluded by collodium for 4 hours. Rolipram injections (1 mg/kg) were started before bacterial inoculation and repeated at 24-hour intervals in the PYN + rolipram groups until death. The rats were killed at the indicated times. Malondialdehyde and nitric oxide levels and superoxide dismutase and catalase activities were determined in kidney homogenates. Histopathologic examinations were also performed. RESULTS: Tissue malondialdehyde and nitric oxide levels and superoxide dismutase and catalase activities were significantly increased in the kidneys from the PYN groups. However, rolipram administration reduced renal malondialdehyde and nitric oxide levels and enhanced superoxide dismutase and catalase activities. The histopathologic examinations demonstrated that rolipram treatment reduced the inflammation grade in the kidney specimens. CONCLUSIONS: The results of our study have shown that rolipram has a protective effect on renal tissue from E. coli-induced oxidative injury. Therefore, phosphodiesterase 4 inhibitors might be a novel therapeutic option for the prevention and/or management of acute PYN.