Adaptive Resistance Mutations at Suprainhibitory Concentrations Independent of SOS Mutagenesis.

Emergence of resistant bacteria during antimicrobial treatment is one of the most critical and universal health threats. It is known that several stress-induced mutagenesis and heteroresistance mechanisms can enhance microbial adaptation to antibiotics. Here, we demonstrate that the pathogen Bartonella can undergo stress-induced mutagenesis despite the fact it lacks error-prone polymerases, the rpoS gene and functional UV-induced mutagenesis. We demonstrate that Bartonella acquire de novo single mutations during rifampicin exposure at suprainhibitory concentrations at a much higher rate than expected from spontaneous fluctuations. This is while exhibiting a minimal heteroresistance capacity. The emerged resistant mutants acquired a single rpoB mutation, whereas no other mutations were found in their whole genome. Interestingly, the emergence of resistance in Bartonella occurred only during gradual exposure to the antibiotic, indicating that Bartonella sense and react to the changing environment. Using a mathematical model, we demonstrated that, to reproduce the experimental results, mutation rates should be transiently increased over 1,000-folds, and a larger population size or greater heteroresistance capacity is required. RNA expression analysis suggests that the increased mutation rate is due to downregulation of key DNA repair genes (mutS, mutY, and recA), associated with DNA breaks caused by massive prophage inductions. These results provide new evidence of the hazard of antibiotic overuse in medicine and agriculture.

Concentration of amikacin sulphate in synovial fluid when given in combination with dexamethasone phosphate in intravenous regional limb perfusion in standing horses.

Eight horses underwent IVRLP at two occasions through a 23-gauge 2 cm long butterfly catheter. Regional anaesthesia of the ulnar, median and medial cutaneous antebrachial nerves was performed prior, and an 8 cm rubber tourniquet was placed on the proximal radius for 30 minutes following the infusion. The first infusion consisted of 2 g of amikacin sulphate and 10 mg of dexamethasone phosphate diluted with 0.9% NaCl to a total volume of 100 ml. The second perfusion was performed after a 2-week washout period, the same protocol was used but without dexamethasone phosphate. Synovial fluid samples were collected from the metacarpophalangeal joint at T = 0, 0.5, 2, 12, 24 and 36 h post-infusion. Synovial fluid amikacin sulphate concentrations were determined by use of liquid chromatography/tandem mass-spectrometry. All horses (n = 8) remained healthy throughout the study, and no adverse effects associated with the study were encountered. No statistically significant differences were found in synovial fluid amikacin sulphate concentrations between the treatment and the control group at any of the time points. In conclusion, dexamethasone phosphate can be used in IVRLP concomitantly with amikacin sulphate in cases of distal limb inflammation and pain without decreasing the synovial fluid concentration of amikacin sulphate.

Pharmacokinetics of regional limb perfusion using a combination of amikacin and penicillin in standing horses.

The objectives of this study were to evaluate the compatibility and the pharmacokinetic properties of combined amikacin and penicillin administration by intravenous regional limb perfusion (IVRLP) in horses. A tourniquet was applied proximal to the carpus of 7 clinically healthy adult horses and 2 g of amikacin and 10 × 106 IU of penicillin (100 mL total volume) were sequentially injected into the cephalic vein just distal to the tourniquet. Synovial samples were collected from the joint at several times after injection. All samples were analyzed for amikacin and penicillin concentration. The mean maximum concentration (Cmax) of both amikacin and penicillin was over 10-fold the relevant minimal inhibitory concentration (MIC) for all horses and remained above those MICs for at least 24 hours. The results of this study indicate that combining amikacin with penicillin during IVRLP in normal horses delivers high therapeutic synovial concentrations of both drugs.

Pharmacocinétique de la perfusion régionale des membres en utilisant une combinaison d'amikacine et de pénicilline chez des chevaux debout. Les objectifs de cette étude consistaient à évaluer la compatibilité et les propriétés pharmacocinétiques de l'administration combinée d'amikacine et de pénicilline par perfusion intraveineuse régionale des membres (PIRM) chez les chevaux. Un tourniquet a été appliqué proximalement au carpe de sept chevaux adultes en bonne santé clinique et 2 g d'amikacine et 10 × 106 UI de pénicilline (volume total de 100 ml) ont été injectés en séquence dans la veine céphalique légèrement distale au tourniquet. Des échantillons synoviaux ont été prélevés de l'articulation plusieurs fois après l'injection. Tous les échantillons ont été analysés pour la concentration d'amikacine et de pénicilline. La concentration maximale moyenne (Cmax) de l'amikacine et de la pénicilline était plus de 10 fois supérieure à la concentration inhibitrice minimale (CIM) pertinente pour tous les chevaux et est demeurée au-dessus de ces CIM pendant au moins 24 heures. Les résultats de cette étude indiquent que la combinaison de l'amikacine avec la pénicilline durant la PIRM chez des chevaux en santé offre des concentrations synoviales thérapeutiques élevées des deux médicaments.(Traduit par Isabelle Vallières).

Pharmacokinetics of ceftazidime after regional limb perfusion in standing horses.

OBJECTIVE: To determine the metacarpophalangeal joint fluid concentrations of ceftazidime administered via regional limb perfusion (RLP). ANIMALS: Eight healthy horses. METHODS: RLP was performed by injecting 2 g of ceftazidime and 60 mL of perfusate volume in the cephalic vein of standing, sedated horses. Serum and synovial fluid from the metacarpophalangeal joint were collected before perfusion and at 0.5, 2, 6, 12, 24 hours postperfusion. Ceftazidime concentrations were measured via liquid chromatography. Maximal concentration (Cmax ), area under the curve (AUC), half-life of the drug (T ½), and the timing of Cmax (Tmax ) were determined to assess ceftazidime as a candidate drug for RLP. Continuous parameters were compared with the Mann-Whitney U test. P value ≤ .05 was considered statistically significant. RESULTS: The Cmax of ceftazidime in synovial fluid (235 µg/mL) was 15 times higher than the minimal inhibitory concentration (MIC) for most bacteria involved in orthopedic infections, including resistant pathogens such as Pseudomonas aeruginosa (MIC = 16 µg/mL). However, synovial concentrations decreased quickly and remained above the MIC in only 1 horse by 6 hours postperfusion. CONCLUSION: RLP generated high synovial fluid concentrations of ceftazidime in the distal limb, but these concentrations decreased rapidly below the deliberately high MIC selected. CLINICAL RELEVANCE: Once daily RLP, as applied in our study, with 2 g ceftazidime in standing horses, cannot be recommended for use in a clinical setting.

The Effect of Perfusate Volume on Amikacin Concentration in the Metacarpophalangeal Joint Following Cephalic Regional Limb Perfusion in Standing Horses.

OBJECTIVE: To determine the influence of 3 perfusate volumes on amikacin concentration in the metacarpophalangeal joint following cephalic regional limb perfusion (RLP) in standing horses. ANIMALS: Seven healthy horses. METHODS: Three perfusate volumes (100, 60, and 30 mL), containing 2 grams of amikacin, were tested during intravenous RLP at the cephalic vein, placing the tourniquet at mid antebrachium, in standing sedated horses. Synovial fluid was collected from the metacarpophalangeal joint before perfusion and at 30 and 120 minutes after perfusion. Serum samples were taken from the jugular vein at the same time points. Samples were analyzed for amikacin concentrations and a repeated measures ANOVA, followed by least squares difference pairwise comparisons to identify differences in amikacin concentration across perfusate volumes. Differences were considered significant at P<.05. RESULTS: The mean amikacin concentration in synovial fluid at 30 minutes after perfusion was significantly higher following perfusate volume of 100 mL (579 µg/mL), compared to volumes of 60 mL (227 µg/mL) or 30 mL (282 µg/mL) (P<.05). When a threshold of 160 µg/mL was used, more horses reached the synovial therapeutic threshold following perfusate volume of 100 mL (100%), than horses receiving 60 mL (43%) and 30 mL (57%) at 30 minutes after injection. CONCLUSION: The use of 100 mL volume for RLP at the cephalic vein in standing horses resulted in higher concentration of amikacin in the synovial fluid and is recommended for use in clinical cases.

Roxithromycin Pharmacokinetics in Hospitalized Geriatric Patients: Oral Administration of Whole Versus Crushed Tablets.

BACKGROUND: Drug administration as tablets to debilitated elderly patients in crushed form can modify the pharmacokinetic characteristics of the active components. Only scarce information is available on the pharmacokinetics when administered in such form. The aim of this study was to evaluate the pharmacokinetics of roxithromycin administered in crushed form and to compare it with the pharmacokinetics of a group of geriatric patients receiving it in the conventional tablet form. METHODS: Twenty patients from the acute ward of the Shmuel Harofeh Geriatric Medical Center in stable, clinical, and hemodynamic condition were studied. Patients in group 1 (n = 10) received medications orally in tablet form. Group 2 (n = 10) included age- and disease-matched patients from the same department, who received oral roxithromycin in crushed tablet form. The mean daily dose was the same in both groups: 300 mg (150 mg twice daily). The patients received the drug for 3 days before the initiation of the study. Blood samples for determination of the roxithromycin concentration were taken at the baseline, 1 hour before the drug administration, and at 1, 3, 4, 6, 8, and 10 hours after drug administration. Roxithromycin concentration was measured by a liquid chromatography-tandem mass spectrometry method. RESULTS: Pharmacokinetic parameters of roxithromycin were significantly different between the 2 groups: the Cmin and Cmax were significantly higher, the tmax significantly longer, AUC0-10 larger, and CL/F smaller in group 2. CONCLUSIONS: Roxithromycin pharmacokinetic parameters were significantly different between the 2 patient groups resulting in higher drug serum concentrations in the crushed tablets group. The impact of the increased drug exposure is unclear.

CYP2D6 genotyping in paediatric patients with autism treated with risperidone: a preliminary cohort study.

AIM: To evaluate the association between cytochrome P450 2D6 (CYP2D6) phenotypes in paediatric patients with autistic spectrum disorders (ASD) treated with risperidone, adverse drug reactions (ADRs), and drug efficacy. METHOD: An observational cohort study of 40 children (34 males, six females; median age 7y range 3-18y) with autistic disorder, pervasive developmental disorder not otherwise specified, or Asperger syndrome diagnosed using the Autism Diagnostic Interview-Revised and treated with risperidone for at least 3 months. Charts were reviewed for demographic and clinical information, response to treatment was assessed by parents and the treating neurologist on a three-point scale, and information about ADRs was collected. Trough plasma levels of risperidone and its metabolites were determined and CYP2D6 genotyping was performed. RESULTS: Twenty-six patients responded to therapy and 11 patients exhibited ADRs. CYP2D6 genotyping showed two patients to be poor metabolizers, two ultra-rapid metabolizers, seven intermediate metabolizers, and 29 extensive metabolizers. Both ultra-rapid metabolizer patients were non-responders and had no ADRs. In contrast, both poor metabolizer patients were responders but experienced ADRs. No correlation was found between risperidone dosage and either risperidone or drug metabolite plasma levels. There was no difference in risperidone or metabolite plasma levels when comparing responders to non-responders, or when comparing patients with or without ADRs. INTERPRETATION: In patients with ASD treated with risperidone, a CYP2D6 phenotype may be associated with response to treatment and development of ADRs.

A Multi-Residue Analytical Method for Assessing the Effects of Stacking Treatment on Antimicrobial and Coccidiostat Degradation in Broiler Litter.

Antimicrobial drugs and coccidiostat compounds are commonly used in poultry farming. These compounds are subsequently excreted and released into the environment via broiler litter (BL) and can re-enter the food chain as fertilizer or animal feed. Such residue in animal feed can encourage the appearance of antibiotic-resistant bacteria as well as toxicity. Most analytical methods used to identify and quantitate these drug residues are traditional, and are specific to some antimicrobials and present limitations in assessing complex matrixes like BL. The aim of this study was to develop a multi-residue analytic method for assessing 30 antimicrobial drugs and coccidiostats associated with BL. We investigated the presence and the effects of biotic stack treatment on the degradation of drug residue in BL. Liquid-liquid extraction (LLE) and solid phase extraction (SPE) were replaced by Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) clean-up steps and detected by liquid chromatography mass spectrometry (LC/MS/MS). Results show that a wide spectrum of residues were detected from 0.4 to 8.9 mg kg-1. Following lab-scale stacking treatment, tilmicosin and eight coccidiostats persisted in BL (26-100%). This research supports the need for better understanding, regulation, and management of the use of BL that might carry a high risk of residue drugs.

Possible associations between prenatal exposure to environmental pollutants and neurodevelopmental outcome in children.

This study aimed to evaluate associations between prenatal and childhood exposure to phthalates and prenatal exposure to polychlorinated biphenyls (PCBs) and the development of 4-year-old children. Urinary metabolites of five phthalates were measured in women upon delivery, as well as serum concentrations of four PCB congeners. Postnatal phthalate metabolites were measured from children's urine obtained at the time of developmental assessment. The primary outcome was cognitive function as evaluated by the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III) administered at 4 years. Secondary outcomes were motor function and response to sensory stimuli as evaluated by the Developmental Coordination Disorder Questionnaire (DCDQ) and Short Sensory Profile (SSP) that the mothers filled out, respectively. The study included 57 mother-child pairs. Higher maternal phthalate metabolite concentrations were inversely associated with WPPSI-III scores among boys and not among girls. After using linear regression models and controlling for confounding variables, we found that higher levels of monobenzyl phthalate (MBzP) were the ones associated with lower WPPSI-III scores (p=0.004, 95 %CI [-14.18; -3.16]), lower DCDQ scores (p=0.007, 95 %CI [-6.08; -1.17] and lower SSP scores (p=0.004, 95 %CI [-7.47; -1.79]). No association was found between child urinary phthalate metabolite concentrations or maternal PCB blood concentrations and developmental function. These findings indicate that higher prenatal phthalate metabolite levels may be associated with deficits in neurologic development of young boys.

Association between prenatal phthalate exposure and ano-genital indices among offsprings in an Israeli cohort.

Background: In-utero phthalate exposure was shown to be associated with shortened anogenital distance (AGD) in male newborns, but findings among female are inconsistent. While phthalate exposure among pregnant women in Israel is widespread, no study has examined the association with offspring AGD. The objective of the current study was to investigate the association between maternal phthalates urinary concentration and offspring AGD at time of delivery among a birth cohort in Israel. Methods: We measured spot urinary concentration of monobutyl phthalate (MBP), monobenzyl phthalate (MBzP), mono-2-ethyl-5-carboxypentyl phthalate (MECPP), mono-2-ethyl-5-hydroxyhexylphthalate (MEHHP), mono-2-ethyl-5-oxohexyl phthalate (MEOHP) among women presenting to the delivery room at Shamir Medical Center in Israel. Birthweight, length and AGD were measured in all newborns using a standardized protocol. Each AGD measurement was adjusted to weight (ano-genital index). Confounders included socio-demographic characteristics, comorbidities and obstetrical history. Univariate and multivariate analyses assessed the associations between phthalates, confounders and AGD. Results: Overall, 193 mother and infant were analyzed. All newborns were born at term and had normal Apgar scores. Mean maternal age was 32 ± 4.7 years old. Mean birth weight and pregnancy week were 3183 ± 498 g and 39 ± 1.3, respectively. Median (IQR) urinary phthalate concentration adjusted to creatinine (ug/g) were 3.96 (2.2-6.6), 1.22 (0.7-2), 10.84 (7-20.4), 6.36 (3.3-11.2) and 0.64 (0.4-1.1) for MBP, MBzP, MECPP, MEHHP and MEOHP, respectively. Univariate comparison showed a significant association between higher than median MBzP concentration, higher Ano-Fourchetal index (AFI: 4.4 vs. 4.1, p = 0.037) and Ano-clitoral index (ACI: 11.5 vs. 10.4, p = 0.032) in infants. Total urinary phthalates concentration ≥26.25 µg/g was significantly associated with smaller penile width index (3.5 vs. 3.7, p = 0.022), higher ACI (11.6 vs. 10.3, p = 0.013) and a trend towards significance for higher AFI (4.3 vs. 4.1, p = 0.055). Following multivariate linear regression only PWI remained significantly associated with total phthalate urinary concentration. Conclusions: Maternal urinary phthalates concentration at delivery were not associated with female AGD, but total urinary phthalate concentration were inversely associated with penile width.

Pharmacokinetics of ciprofloxacin in hospitalized geriatric patients: comparison between nasogastric tube and oral administration.

OBJECTIVES: Drug administration to debilitated elderly patients on enteral feeding through a nasogastric tube (NGT) can modify the pharmacokinetic characteristics of the drug and influence its therapeutic blood concentration. The aim of this study was to evaluate the pharmacokinetics of ciprofloxacin administered through an NGT and to compare it with those of a group of patients receiving the drug orally. METHODS: Twenty patients in stable clinical and hemodynamic condition from the long-term care ward of a geriatric multilevel hospital were studied. Patients in group 1 (n = 10) had oropharyngeal dysphagia and received food and medications, including ciprofloxacin, by NGT. Group 2 (n = 10) included age- and disease-matched orally fed patients from the same department receiving ciprofloxacin orally. Blood samples for ciprofloxacin concentration were taken at steady state, before drug administration, time 0, and at 1, 2, 3, 4, 6, 8, and 10 hours after drug administration. Ciprofloxacin was measured using liquid chromatography with tandem mass spectrometric detection. The mean daily dose was the same in both the groups: 1000 mg (500 mg twice daily). RESULTS: Pharmacokinetic parameters of ciprofloxacin were not significantly different between the 2 groups: trough concentrations were 1.24 ± 0.95 µg/mL (0.25-3.67 µg/mL) versus 1.30 ± 0.61 µg/mL (0.21-2.36 µg/mL) (P = 0.76); Cmax 3.30 ± 2.16 µg/mL (1.54-8.62 µg/mL) versus 4.24 ± 1.99 µg/mL (2.24-9.02 µg/mL) (P = 0.356); tmax 2.8 ± 1.5 versus 3.1 ± 2.8 hours (P = 0.799); and AUC0-10 20.2 ± 12.1 µg·h·mL (9-51.07 µg·h·mL) versus 24.4 ± 13.0 µg·h·mL (5.57-52.48 µg·h·mL) (P = 0.493), in the oral fed versus NGT, respectively. CONCLUSIONS: Ciprofloxacin pharmacokinetic parameters are not significantly different between patients receiving the drug through NGT compared with those who received it orally, and therefore, in frail elderly patients, this route of administration can be considered.

Resistant Bacteria in Broiler Litter Used as Ruminant Feed: Effect of Biotic Treatment.

The use of antimicrobial drugs and coccidiostats in poultry farming is widespread, with a significant proportion of these drugs being excreted and released into the environment. The residues of such drugs in poultry litter (PL) can result in the development of antibiotic-resistant bacteria. The impact of different biotic treatments (aerobic, anaerobic, and stacking) on broiler litter (BL) before its use as animal feed has not been studied extensively, nor have the differences between antimicrobial-dependent and independent broiler farms been investigated. This study aimed to determine the resistant bacteria in BL used as ruminant feed before and after litter treatment. The results show that the most resistant bacteria before BL treatment were the Enterococcus species. This study also found that the quantity of amoxicillin-resistant Enterococcus detected in samples from antimicrobial-dependent farms was significantly higher than in those from antimicrobial-independent farms. Additionally, 14% of bacteria were multi-resistant to tetracycline, sulfafurazole, and erythromycin in antimicrobial-independent farm litters, significantly lower than those measured in antimicrobial-dependent broiler farm litter. This study highlights the importance of better understanding, regulating, managing, and using animal waste appropriately to reduce the number of antibiotic-resistant bacteria and minimize the use of antimicrobials that carry high risks for animals, humans, and the environment.

Ensiling process and pomegranate peel extract as a natural additive in potential prevention of fungal and mycotoxin contamination in silage.

A study was conducted on six animal feed centers in Israel where fungal and mycotoxin presence was examined in maize and wheat silages. Fumonisin mycotoxins FB1 and FB2 were present in every maize silage sample analyzed. Interestingly, no correlation was found between the occurrence of specific mycotoxins and the presence of the fungal species that might produce them in maize and wheat silages. We further investigated the effect of pomegranate peel extract (PPE) on Fusarium infection and fumonisin biosynthesis in laboratory-prepared maize silage. PPE had an inhibitory effect on FB1 and FB2 biosynthesis by Fusarium proliferatum, which resulted in up to 90 % reduction of fumonisin production in silage samples compared to untreated controls. This finding was supported by qRT-PCR analysis, showing downregulation of key genes involved in the fumonisin-biosynthesis pathway under PPE treatment. Our results present promising new options for the use of natural compounds that may help reduce fungal and mycotoxin contamination in agricultural foodstuff, and potentially replace traditionally used synthetic chemicals.

Maternal Exposure to Polychlorinated Biphenyls and Asthma, Allergic Rhinitis and Atopic Dermatitis in the Offspring: The Environmental Health Fund Birth Cohort.

Background: Polychlorinated biphenyls (PCBs) are persistent organic pollutants banned for use worldwide. Due to their biodegradation resistance, they accumulate along the food chain and in the environment. Maternal exposure to PCBs may affect the fetus and the infant. PCBs are immunotoxic and may damage the developing immune system. PCBs are associated with elevated IgE antibodies in cord blood and are considered to be predictive of atopic reactions. Several studies on the association between prenatal exposure to PCBs and atopic reactions were previously published, albeit with conflicting results. Objectives: To examine the association between maternal PCBs levels and atopic reactions in their offspring. Methods: During the years 2013-2015, a prospective birth cohort was recruited at the delivery rooms of Shamir Medical Center (Assaf Harofeh) and "Dana Dwek" Children's Hospital. Four PCBs congeners were investigated: PCBs 118, 138, 153, and 180. In 2019, when children reached the age of 4-6 years, mothers were interviewed using the ISAAC questionnaire to assess symptoms of atopic reactions, including asthma, allergic rhinitis, and atopic dermatitis. Results: One hundred and fifty mother-child dyads were analyzed. No significant differences were found in the median serum PCBs concentrations of each studied congener or total PCBs for asthma, allergic rhinitis, atopic dermatitis diagnosis, or parent-reported symptoms. No association was found between exposure to total PCBs and the risk for asthma symptoms or diagnosis, adjusted to maternal age and family member with atopic condition: aOR = 0.94, 95%CI: (0.88; 0.99). No association was observed between each studied PCB congener and asthma symptoms or diagnosis. The same results were found also for other studied outcomes-allergic rhinitis and atopic dermatitis. Conclusion: Our study joins a series of previous studies that attempt to shed light on environmental exposures in utero as influencing factors for atopic conditions in children. Our results reflect the complexity of the pathophysiology of these phenomena. No relationship between maternal serum PCBs levels was demonstrated for asthma, allergic rhinitis, or atopic dermatitis. However, additional multi-participant studies, with longer, spanning into later pediatric age follow up are needed.

Synovial Concentration of Trimethoprim-Sulphadiazine Following Regional Limb Perfusion in Standing Horses.

The aim of this study was to investigate the safety and pharmacokinetics of trimethoprim-sulphadiazine administered via intravenous regional limb perfusion (IVRLP) into the cephalic vein. According to the hypothesis, the drug could be administered without adverse effects and the synovial concentrations would remain above the minimum inhibitory concentration (MIC) for trimethoprim-sulphadiazine (0.5 and 9.5 µg/mL) for 24 h. Ten (n = 10) horses underwent cephalic vein IVRLP with an Esmarch tourniquet applied for 30 min. Four grams (4 g) of trimethoprim-sulphadiazine (TMP-SDZ) were diluted at 0.9% NaCl for a total volume of 100 mL. Synovial fluid and blood samples were obtained immediately before IVRLP and at 0.25, 0.5, 2, 6, 12 and 24 h after the initiation of IVRLP. Trimethoprim and sulphadiazine concentrations were determined using a method based on liquid chromatography/tandem mass spectrometry. The Cmax (peak drug concentration) values were 36 ± 31.1 and 275.3 ± 214.4 µg/mL (TMP and SDZ). The respective tmax (time to reach Cmax) values were 20 ± 7.8 and 26.4 ± 7.2 min. The initial synovial fluid concentrations were high but decreased quickly. No horse had synovial concentrations of trimethoprim-sulphadiazine above the MIC at 12 h. Severe vasculitis and pain shortly after IVRLP, lasting up to one week post-injection, occurred in five out of 10 horses. In conclusion, IVRLP with trimethoprim-sulphadiazine cannot be recommended due to the low concentrations of synovial fluid over time and the frequent severe adverse effects causing pain and discomfort in treated horses. Thus, in cases of septic synovitis with bacteria sensitive to trimethoprim-sulphadiazine, other routes of administration should be considered.

A survey of arsenic, mercury, cadmium, and lead residues in seafood (fish, crustaceans, and cephalopods) from the south-eastern Mediterranean Sea.

Seafood is capable of bioaccumulating heavy metals (HM), making it a potentially major dietary source of HM for humans. Presently, little data exists on seafood from the eastern-most boundary of the Mediterranean Sea. This study aims to provide exposure insight of the Israeli population to HM through the consumption of locally caught seafood by assessing the levels of arsenic, mercury, cadmium, and lead in raw tissues of seafood. A wide survey of local fisheries was conducted providing 296 samples from 11 different species, including seven fish, two crustacean, and two cephalopod species. Total arsenic, cadmium, and lead were analyzed by graphite-furnace atomic absorption. Total mercury was measured by cold-vapor mercury analyzer. Arsenic speciation was performed by anion chromatography-inductively coupled plasma sector field mass spectrometry. Results suggested that the total arsenic concentrations were significantly higher in crustaceans and cephalopods than fish. Arsenic speciation revealed two samples that exceed 1 mg/kg of inorganic arsenic, whereas methylated arsenic was below the detection limit. Elevated mercury levels were detected in the commercial benthic species Mullus barbatus (red mullet), cadmium was detected in one-third of the samples, and lead detected in eight samples. Comparing the results to health guidelines, 99.4% of seafood tested in this study abide with acceptable levels of heavy metals in seafood, as defined by both Israeli and European Union guidelines.

The Concentration of Metronidazole in the Distal Interphalangeal Joint following Intravenous Regional Limb Perfusion via the Cephalic Vein in Standing Horses.

OBJECTIVE: The aim of this study was to determine the concentration of metronidazole in the distal interphalangeal joint (DIPJ) of the thoracic limb after administering metronidazole to standing horses by intravenous regional limb perfusion (IVRLP). METHODS: Eleven healthy horses had a wide rubber tourniquet applied to the proximal aspect of the antebrachium for 0.5 hours and 500 mg of metronidazole diluted in physiologic saline solution to a total volume of 108 mL was administered by cephalic IVRLP. Synovial fluid samples were collected from the DIPJ before perfusion and at 0.25, 0.5, 2, 12 and 24 hours. Blood samples were obtained at the same time points for serum analysis. Concentrations of metronidazole were determined by liquid chromatography/tandem mass spectrometry. RESULTS: Four horses were excluded due to low synovial fluid concentrations and not completing the full tourniquet application time. The C max in the synovial fluid was 327 ± 208 µg/mL, and the t max was 26 ± 7 minutes. Only the concentrations of metronidazole at time points 0.25 and 0.5 hours were significantly different (p < 0.001) from synovial concentration before perfusion. The serum C max was 1.78 ± 0.93 µg/mL, and the t max was 76 ± 52min. CONCLUSION: Metronidazole administered by IVRLP reached high concentrations in the synovial fluid at 0.5 hours. However, the concentrations rapidly decreased below the minimum inhibitory concentration of potential target pathogens. Effectiveness of metronidazole administered by IVRLP as a sole therapy against anaerobic infections of synovial structures of the distal limb cannot be determined by a pharmacokinetic study. However, the present study serves as the basis for future carefully planned clinical trials.

Maternal and Newborn Thyroid Hormone, and the Association With Polychlorinated Biphenyls (PCBs) Burden: The EHF (Environmental Health Fund) Birth Cohort.

Background: Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants found in human tissues. PCBs can be transferred through the placenta and may disrupt the maternal thyroid homeostasis, and affect fetal thyroid hormone production. Several studies have shown that intrauterine exposure to PCBs might be associated with abnormal levels of thyroid hormones in mothers and their offspring. Objectives: To examine the associations between environmental exposure to PCBs and thyroid hormone levels in mothers and newborns. Methods: The EHF-Assaf-Harofeh-Ichilov cohort includes 263 mothers-newborns dyads. A total of 157 mother-newborn dyads had both PCBs and thyroid function measures. Regression models were used to estimate associations between maternal PCB exposure and maternal and newborn thyroid function, controlling for possible confounders. Results: Four PCBs congeners were analyzed: PCBs 118, 138, 153, and 180. ∑PCBs median (IQR) level was 14.65 (2.83-68.14) ng/g lipids. The median maternal thyroid-stimulating hormone (TSH) level was 2.66 (0.70-8.23) µIU/ml, the median maternal free thyroxine (FT4) level was 12.44 (11.27-13.53) µg/dL, the median maternal thyroid peroxidase antibodies (TPO Ab) level was 9.6 (7.36-12.51) IU/mL. Newborns' median total thyroxine (T4) level was 14.8 (7.6-24.9) µg/dL. No association was found between exposure to different congeners or to ∑PCBs and maternal TSH, FT4, thyroglobulin autoantibodies (Tg Ab), TPO Ab and newborn total T4 levels. In multivariable analysis a 1% change in ∑PCBs level was significantly associated with a 0.57% change in maternal TSH levels in women with body mass index (BMI) < 19. The same association was observed for each of the studied PCB congeners. Maternal TPO Ab levels statistically significantly increased by 0.53 and 0.46% for 1% increase in PCB 118 and 153 congeners, respectively. In women with BMI > 25, the association between the PCBs levels and maternal TSH levels was in the opposite direction. No association was found in women with normal BMI (19-24.9). Conclusions: Background exposure to environmentally relevant concentrations of some PCBs can alter thyroid hormone homeostasis in pregnant women and might be associated with abnormal TSH levels and TPO-Ab in women with low BMI. However, these findings require further investigation.

Time to Peak Concentration of Amikacin in the Antebrachiocarpal Joint Following Cephalic Intravenous Regional Limb Perfusion in Standing Horses.

OBJECTIVE: The aim of this study was to determine the time (Tmax) to the maximum concentration (Cmax) of amikacin sulphate in synovial fluid of the radiocarpal joint (RCJ) following cephalic intravenous regional limb perfusion (IVRLP) using 2 g of amikacin sulphate. METHODS: Cephalic IVRLP was performed with 2 g of amikacin sulphate diluted in 0.9% NaCl to a total volume of 100 mL in six healthy adult mixed breed mares. An Esmarch's rubber tourniquet was applied for 30 minutes and the antibiotic solution was infused through a 23-gauge butterfly catheter. Synovial fluid was collected from the RCJ prior to the infusion and at 5, 10, 15, 20, 25 and 30 minutes after completion of IVRLP. The tourniquet was removed after the last arthrocentesis. Synovial fluid amikacin sulphate concentrations were determined by liquid chromatography/tandem mass spectrometry. RESULTS: The calculated mean Tmax occurred at 15 minutes (range: 10-20 minutes) post-perfusion. The highest synovial fluid amikacin sulphate concentration was noted at 10 minutes in 2 horses, 15 minutes in 2 horses and 20 minutes in 2 horses. The highest mean concentration was 1023 µg/mL and was noted at 20 minutes. Synovial mean concentrations were significantly different between 15 and 30 minutes. CLINICAL SIGNIFICANCE: In this study no Tmax occurred after 20 minutes; thus, 30 minutes of tourniquet application time appear to be excessive. The 20 minutes duration of tourniquet application appears sufficient for the treatment of the RCJ in cephalic IVRLP using 2 g amikacin sulphate in a total volume of 100 mL.

The effect of tertiary treated wastewater on fish growth and health: Laboratory-scale experiment with Poecilia reticulata (guppy).

Treated wastewater (TWW) constitutes a sustainable water resource and has been used for fish culture in some countries around the world, although there are no comprehensive data on the effect of TWW on fish growth and health in the context of aquaculture production. Our objectives were to examine how fish culture in TWW affected fish growth and fitness, as well as compliance with the international standards for safe consumption. Guppy (Poecilia reticulata) fingerlings were reared in 0%, 50% and 100% tertiary TWW (TTWW), from the age of five days, for a period of four months. In water analyses, 33 out of 67 tested organic micropollutants (OMPs) were detected in the TTWW samples at least once, at concentrations that are typically reported in domestic TTWW. Fish survival ranged between 77-80% and did not differ between treatment groups. Fish growth and mortality following challenge infection with Tetrahymena sp. (which ranged between 64-68%), were similar among treatment groups. Of tested immunological parameters, lysozyme and anti-protease was similar among treatments while complement activity was highest in the 50% TTWW-reared fish. No abnormalities were observed in the histopathological analysis. Levels of heavy metals, polychlorinated-biphenyls (PCBs) and organochlorines (OCs) in fish were below the detection limit and below the Food and Agriculture Organization of the United Nations (FAO) and the European Union EU maximal permitted levels in food fish. Results suggest that the yield of fish grown in TTWW is potentially similar to that in freshwater, and the produced fish comply with the standards of consumer safety. The results are in line with previous studies that examined the feasibility of TWW-fed aquaculture.