Assessing malathion residue impact on poultry health, human safety, and production performance.

Over the past decade, food safety has become a major concern due to the intensive use of pesticides. Pesticide contamination has been observed in poultry products when seeds are coated with pesticides or when stored products are exposed to pesticides in warehouses. In this experiment, the residue levels of malathion transferred from corn grain to the different parts of the chicken product, its transfer factors (TFs) and the human dietary risk for consumers were evaluated. Growth performance and carcass parameters of the chicken samples were also determined after different doses of malathion exposure. Malathion residues from different parts of chicken meat (breast, thigh, wing, liver and skin) were extracted by the QuEChERS method and analyzed by liquid chromatography-mass spectrophotometry (LC-MS/MS). A deterministic approach was used to calculate the acute and chronic risk assessment. Body weight, feed conversion ratio and feed intake decreased with increasing malathion dose. In addition to reduced feed intake, cold carcass and liver weights of the chicks were also decreased. The highest residues were found in the skin of the chicken followed by the breast, thigh, wing and liver. The TFs of malathion varied between 0.00 and 0.05 according to the different doses applied (4 mg/kg, 8 mg/kg, 16 mg/kg, 32 mg/kg). The chronic exposure assessment (HQ) showed that consumers of all ages and genders consumed 0.008-0.604% of the acceptable daily intake (0.3 mg/kg body weight (bw)/day) of malathion from chicken products. The acute intake assessment (aHQ) of consumers ranged from 0.00015 to 0.0135% of the acute reference dose (0.3 mg/kg bw). In conclusion the results suggest that the risk associated with the malathion residues in chicken meat was found to be low but the residue levels in meat should not be ignored.

[Silencing of Resistance Mechanism in Vancomycin-Resistance Enterococci Using Antisense RNA of vanA Gene]. / vanA Geninin Antisens RNA'si Kullanilarak Vankomisine Dirençli Enterokoklarda Direnç Mekanizmasinin Susturulmasi.

The World Health Organization has included the problem of antibiotic resistance among the top 10 important health problems in the world. Treatment of infectious diseases has become more difficult due to the spread of antibiotic resistance between bacteria via transposable elements. Vancomycin-resistant enterococci (VRE) are of critical medical and public health importance due to their association with serious nosocomial infections and high risk of death. One of the most important features of VREs is that they have multiple antibiotic resistance and treatment options are reduced. Therefore, new treatment methods are needed. The vanA gene constitutes the building block of the vancomycin resistance mechanism and causes high resistance to vancomycin. In this study, it was aimed to investigate the neutralization of the vancomycin resistance mechanism by creating vanA antisense RNA (asRNA). The vanA positive VRE50 strain in our culture collection which was isolated from the clinical sample, was used to amplify the vanA gene by polymerase chain reaction (PCR). The amplified vanA amplicon was inserted inversely into the pUC19 plasmid by means of the enzyme cutting sites in the primers used. The resulting plasmid was combined with the pAT392 plasmid which can replicate in gram-positive bacteria and a fusion plasmid was created. The fusion plasmid whose orientation was confirmed, was transferred to the wild strain VRE50 by electroporation method. Minimum inhibitory concentration (MIC) values of transformed VRE (tVRE50) and wild type VRE50 strains used as control were determined by the E-Test method. The vancomycin MIC value of the wild type VRE50 strain was determined as 1024 µg/mL and that of the tVRE50 strain was 32 µg/mL and it was determined that the vancomycin resistance of the tVRE50 strain decreased with asRNA (antisense RNA). Antisense RNA technology is an important method for neutralizing the expression of genes. This study showed that neutralization of the vancomycin resistance gene may provide a lower MIC value in a vancomycin-resistant enterococcus strain and lead to increased susceptibility. This new approach provides a new method for VRE treatment by neutralizing the vancomycin resistance mechanism. The result obtained in this study needs to be supported by in vivo tests.

Removal of pesticide residues from apple and tomato cuticle.

Pesticide residues are always an unsolved problem in the world despite all kinds of prevention measures. The present research work is based on a scientific hypothesis, i.e., "The removal of average pesticide residue is inversely proportional to the thickness of cuticle." The effects of boron-containing products and plant-based surfactants were tested for the removal of five pesticides (lambda-cyhalothrin, chlorpyrifos, diflubenzuron, metaflumizone, acetamiprid) on tomatoes and apples. Boron-containing products were able to remove the pesticide residues on average between 58.0 and 72.6% in tomatoes and 33.2-58.8% in an apple. While plant-based surfactants removed residues on average between 58.5 and 66.6% in tomatoes and 41.0-53.2% in an apple. The highest removal rate was 72% with etidot at 1%. The solution of 1% C8-C10 provided 66.6% average removal for tomatoes. Less removal was achieved in apples. For an apple, Log Kow and molecular mass (independent variables) were significant with p < 0.01, and the coefficient of determination (R2) was > 0.87. However, the multiple linear regression analysis for ground colemanite was significant with R2 of 0.96. In tomatoes, neither Log Kow nor molecular mass as significant. The correlation was found between the physical and chemical properties of pesticides, but it is estimated that the thickness of the cuticle is effective in removing pesticides.

Use of trans-complementation method to determine the effects of various ftsI mutations on ß-lactamase-negative ampicillin-resistant (BLNAR) Haemophilus influenzae strains.

Haemophilus influenzae is a causative agent of serious infections, especially among children. ß-lactam antibiotics are commonly used for the treatment of these infections. Among H. influenzae isolates, ß-lactam resistance is due to the presence of ß-lactamase, or to mutations in the ftsI gene that generate altered PBP3 (penicillin-binding protein 3) with reduced affinity for ß-lactams (BLNAR-ß-lactamase-negative, ampicillin-resistant). Wild-type ftsI gene encoding for PBP3 was amplified in whole from ß-lactam susceptible H. influenzae Rd and cloned in pLS88 plasmid to obtain pADUTAS17, which was then used to transform known BLNAR strains, susceptible strains, and a strain (CF55) with wild-type ftsI but unexplained reduced ß-lactam susceptibility. Ampicillin and cefotaxime MICs (minimum inhibitory concentration) were determined after transformation with pLS88 and pADUTAS17 plasmids. The results showed that antibiotic susceptibilities were not affected by trans-complementation for isolates carrying wild-type ftsI gene. However, trans-complementation for all BLNAR strains showed decreases between - 0.957 and 0.5-fold for ampicillin and cefotaxime, confirming the role of the PBP3 substitutions in the BLNAR phenotype of these isolates. The first article showed that trans-complementation might be a useful tool in the investigation of decreased ß-lactam susceptibility in H. influenzae.

Metagenomic analysis of wastewater phageome from a University Hospital in Turkey.

Phage DNA analysis gives opportunity to understand living ecosystem of the environment where the samples are taken. In the present study, we analyzed phage DNA obtained from wastewater sample of university hospital sewage. After filtration, long high-speed centrifugation was done to collect phages. DNA was extracted from pellet by phenol chloroform extraction and used for NGS sequencing. The host profile, taxonomic and functional analyses were performed using MG-RAST, and ResFinder program was used for resistance gene detection. High amounts of reads belong to bacteriophage groups (~ 95%) from our DNA sample were obtained and all bacteriophage reads were found belonging to Caudovirales order and Myoviridae (56%), Siphoviridae (43%), and Podoviridae (0.02%) families. The most common host genera were Escherichia (88.20%), Salmonella (5.49%) and Staphylococcus (5.19%). SEED subsystems hits were mostly structural parts and KEGG Orthology hits were nucleotide- and carbohydrate metabolism-related genes. No anti-microbial resistance genes were detected. Our bacteriophage DNA purification method is favorable for phage metagenomic studies. Dominance of coliphages may explain infrequent Podoviridae. Dominancy of structural genes and auxiliary genes is probably due to abundance of lytic phages in our sample. Absence of antibiotic resistance genes even in hospital environment phages indicates that phages are not important carrier of resistance genes.

Evaluation of pesticide residues in fruits and vegetables from the Aegean region of Turkey and assessment of risk to consumers.

Pesticides may cause a potential risk to human health when applied in excess to control pests, diseases, and weeds in crop fields. In the current study, conducted in the Aegean region of Turkey from 2012 to 2016, a total of 3044 samples of 16 different commodities of fruits and vegetables were screened to identify pesticide residues and health risk to consumers posed by such residues was assessed. Results showed that 354 samples out of the total samples had higher maximum residue limit (MRL) values, while the MRL values were lower in 473 samples. In the study, residues of 64 different pesticides detected in 3044 samples in which 11.6% samples exceeded maximum residue limit (MRL) levels as compared with that of the approved MRL level by the Turkish authorities. Out of total samples, number of samples having high MRL level were as follows: 74 for chlorpyrifos (2.43%), 145 for azoxystrobin (3.8%), 112 for triadimenol (3.8%), 103 for carbendazim (3.4%), 98 for chlorpyrifos (3.2%), 94 for pyrimethanil (3.10%), 90 for cyprodinil (2.9%), 76 for fludioxonil (2.50%), 75 for indoxacarb (2.40%), 66 for imidacloprid (2.10%), and 60 for boscalid (1.90%). Residues of one, two, three, four, and even more than five pesticides were detected, respectively, in 16.1, 5.8, 2.8, 1, and 1.7% of the total test samples. The lowest estimated daily intake (EDI) values ranged from 3.57×10-3 to 8.98. The lower values of hazard quotient (HQ) were obtained in dried apricot, grape, and strawberry with the value of 0.01, although the HQ value in 32 out of 62 pesticides tested was found to be close to 0.

Pine needle and semi-permeable membrane device derived organochlorine compounds (OCPs) concentrations in air in Mersin Province to Taurus, Turkey.

Organochlorine pesticides (OCPs) were analyzed in three different ages (half-, 1.5-, 2.5-year-old) for needles and semi permeable membrane devices (SPMDs) at three deployment periods from sea level to 1881 meter above sea level. Individual HCHs concentrations ranged between 1.4 and 129 pg/g fw depending on the age and sampling season while 2.5-year-old needles showed higher HCHs levels compared to half and 1.5- year-old. Correlation between elevation and HCH concentration in SPMDs was found but not in needle samples. Concentrations of HCHs in SPMDs indicated clearly cold condensation effect on accumulation in winter period and increased with altitude. Concentrations of DDTs in half and 1.5-year-old needles were lower than 2.5-year-old needles. The highest total concentration of DDTs was detected in 1-year-period SPMD. Higher concentrations were found in 2.5-year-old needles for other OCPs. Seasonal and altitude-dependent changes were not observed for other OCPs in SMPDs. Total accumulation of OCPs in SPMDs were found higher than in needles. On the contrary, an increased accumulation rate was observed for HCHs in SPMD. In general, Total concentrations of DDTs and HCHs were similar to total of other OCPs in all altitudes when dominating endosulfan wasnot taken into account in the computation of total concentration of other OCPs.

Organophosphate esters in house dust: A comparative study between Canada, Turkey and Egypt.

Organophosphate esters (OPEs) are commonly used as flame retardants (FRs) and plasticizers. The usage of OPEs has increased recently due to the ban of several brominated flame retardants, but information on levels in the environment, including the indoor environment is still limited. We investigated the occurrence and distribution of 12 OPEs in urban house dust from Vancouver, Canada; Istanbul, Turkey; and Cairo, Egypt. The median ∑OPE concentration was 41.4 µg/g in the Vancouver samples while median levels in Istanbul and Cairo were significantly lower. The median composition profiles of OPEs in Vancouver and Cairo were dominated by tris (2-butoxyethyl) phosphate (TBOEP), accounting for 56 and 92% of total OPEs respectively while it showed a detection frequency of only 14% in Istanbul. Tris (2-chloropropyl) phosphate (TCPP) was the most abundant chlorinated OPE representing 20 and 36% of the total OPEs in Vancouver and Istanbul respectively, but was below the detection limit in the Cairo dust samples. Consistent with other studies, ΣOPE concentrations were ~1 to 2 orders of magnitude higher than PBDEs and currently used flame retardants in the same dust samples. The mean estimated daily intakes (EDI) of ΣOPE from dust were 115, 38 and 9 ng/kg/bw/day in Vancouver, Cairo and Istanbul respectively for toddlers where adults were ~10 times lower. The total toddler OPE intake ranged from 115 to 2900, 38 to 845 and from 9 to 240 ng/kg bw/day across the three cities. TBOEP had the largest contribution to the EDI in both toddler and adults, where toddler TBOEP exposures via dust represented 4% to 80%, 2% to 44% and 0.1% to 6% of the Reference Doses (RfD) in the mean and high intake scenarios for toddlers in Vancouver, Cairo and Istanbul respectively.

Polycyclic aromatic hydrocarbons (PAHs) determined by pine needles and semipermeable membrane devices along an altitude profile in Taurus Mountains, Turkey.

Polycyclic aromatic hydrocarbons (PAHs) were analyzed at different altitudes of Taurus Mountains in semipermeable membrane devices (SPMD) and in half-, one-and-a-half-, and two-and-a-half-year-old pine needles. SPMDs were deployed for three different exposure periods: March to September (Summer), September to March (Winter), and March to March (whole year) at eight sites where needle samples were collected. The values of PAHs in needles were between 4.4 to 6066 pg g/fw in half-year-old, 7.2 to 111,115 pg g/fw in 1.5-year-old, and 9.7 to 85,335 pg g/fw in 2.5-year-old needles. Mass of PAHs collected by SPMDs varied from