Is there any relationship between cytokine spectrum of breast milk and occurence of eosinophilic colitis?

Aim: The aim of our study was to analyse cytokine composition of human milk and its relationship to the development of eosinophilic colitis (EC). Methods: Cytokines were measured by ELISA method in breast milk of 20 mothers of infants who developed EC and 20 controls. Results: We found significantly higher concentrations of interferon‐gamma (IFN‐gamma) (Th1 cytokine) in breast milk received by EC infants compared to controls (p = 0.0004). In contrary, IL‐18 (Th1‐inducing cytokine) was significantly higher in breast milk received by healthy infants comparing to EC infants (p = 0.001). Regulatory cytokine transforming growth factor beta1 (TGF‐beta1) showed higher concentrations in breast milk received by healthy infants, although the difference from EC group was not significant (p = 0.072). Conclusion: The results of our study showed that infants with EC were receiving breast milk with a possibly risky cytokine pattern indicating cytokine imbalance, impaired immunoregulation and the early Th1 shift.     

Carbapenemase activity detection by matrix-assisted laser desorption ionization-time of flight mass spectrometry

Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry is used for the determination of molecular weights of different chemical compounds. We describe here the use of MALDI-TOF mass spectrometry to detect a carbapenem antibiotic, meropenem, and its degradation products. Buffered meropenem solution (0.1 mM Tris-HCl, pH 6.8) was mixed with an overnight culture of bacteria. After 3-h incubation, the reaction mixture was centrifuged, and the supernatant was analyzed by MALDI-TOF mass spectrometry. The presence or absence of peaks representing meropenem and its sodium salts was crucial. The average turnaround time of this test, considering the use of overnight culture, is 4 h. We validated this method for the detection of resistance to carbapenems in Enterobacteriaceae and Pseudomonas aeruginosa mediated by carbapenemase production. A total of 124 strains, including 30 carbapenemase-producing strains, were used in the study. The sensitivity of this method is 96.67%, with a specificity of 97.87%. Our results demonstrate the ability of this method to routinely detect carbapenemases in Enterobacteriaceae and Pseudomonas spp. in laboratories. This assay is comparable with a labor-intensive imipenem-hydrolyzing spectrophotometric assay that is a reference method for the detection of carbapenemase. As demonstrated here, MALDI-TOF mass spectrometry may be used in microbiological laboratories not only for microbial identification but also for other applications, such as studies of mechanisms of antibiotic resistance.     

“Just another drug” for marginalized users: The risks of using synthetic cathinones among NSP clients in the Czech Republic

Background: In several EU countries, synthetic cathinone (SC) use has spread among injecting drug users (IDUs); it has been linked to risk of dependence and HIV/HCV transmission. Aims: To analyze the association between dependence and risky injecting practice with experimental and repeated SC use in the past 12 months among the clients of needle-syringe programs in the Czech Republic. Methods: IDUs in six locations in the Czech Republic were surveyed in 2013 and 2014 (n = 463). Single-predictor multinomial logit models were run to determine SC use upon the Severity of Dependence Scale (SDS) and risky injecting practice; the same predictors were included in the multivariate model with confounders. Findings: SDS score and risky injecting practice were significantly associated with repeated SC use in single-predictor models but not in the multivariate model; SC experimentation was linked to young and male respondents and those who lived in a larger city (>50,000); predictors of repeated SC use were homelessness (AOR = 3.2), co-occurring use of stimulants and opioids (AOR = 4.3), and use of cannabis (AOR = 2.4) in the past month. Conclusions: Repeated SC use was associated with poly-drug use and homelessness; given the rather inferior status of SCs among IDUs, their users face a risk of stigmatization and further marginalization.     

A Method for Evaluation the Fatigue Microcrack Propagation in Human Cortical Bone Using Differential X-ray Computed Tomography

Fatigue initiation and the propagation of microcracks in a cortical bone is an initial phase of damage development that may ultimately lead to the formation of macroscopic fractures and failure of the bone. In this work, a time-resolved high-resolution X-ray micro-computed tomography (CT) was performed to investigate the system of microcracks in a bone sample loaded by a simulated gait cycle. A low-cycle (1000 cycles) fatigue loading in compression with a 900 N peak amplitude and a 0.4 Hz frequency simulating the slow walk for the initialization of the internal damage of the bone was used. An in-house developed laboratory X-ray micro-CT imaging system coupled with a compact loading device were employed for the in situ uni-axial fatigue experiments reaching a 2μm effective voxel size. To reach a comparable quality of the reconstructed 3D images with the SEM microscopy, projection-level corrections and focal spot drift correction were performed prior to the digital volume correlation and evaluation using differential tomography for the identification of the individual microcracks in the microstructure. The microcracks in the intact bone, the crack formation after loading, and the changes in the topology of the microcracks were identified on a volumetric basis in the microstructure of the bone.     

Inhibitory effect of albendazole and its metabolites on cytochromes P450 activities in rat and mouflon in vitro

Cytochromes P450 (CYP) belong to the most important biotransformation enzymes, therefore, their inhibition may lead to serious pharmacological and toxicological consequences. Albendazole (ABZ) is a benzimidazole anthelmintic widely used in human and veterinary medicine. The effects of ABZ on CYP were investigated on the rat (Rattus norvergicus) and mouflon (Ovis musimon) hepatic microsomes. Besides ABZ, its two main metabolites (albendazole sulfoxide, ABZSO, and albendazole sulfone, ABZSOO) were tested to clarify which compound is responsible for the inhibitory effect. After preincubation of microsomes with the benzimidazoles (1, 5 and 25 microM), CYP activities, ethoxyresorufin O-deethylase (EROD) and benzyloxyresorufin O-dearylase activities were measured. The results showed that both ABZ and ABZSO, but not ABZSOO, exhibited significant potency to inhibit CYP activities measured in both tested species. Since ABZ as well as ABZSO are known inducers of EROD activity, our results clearly demonstrate that the drug can act as inducer and also as inhibitor of the same enzyme. In in vitro studies the CYP inhibition may mask the CYP induction. The extent of inhibition observed in mouflon was significantly higher than in rat. This finding emphasizes the importance of performance of inhibition studies in target animal species. Possible consequences of CYP inhibition should be taken into account during the anthelmintic therapy of mouflons with ABZ.     

Pyridostigmine bromide and its relation to Gulf War illness

Abstract

Pyridostigmine bromide acts as a reversible cholinesterase inhibitor that is used at relatively high doses in treatment of Myasthenia gravis and in low dose regimens as prophylaxis against nerve agents poisoning during the Gulf War. The manifestation of late nonspecific symptoms commonly called Gulf War illness has led to the discussion about the role of pyridostigmine bromide in the pathogenesis of this illness. In our study, we described plasma absorption profile of pyridostigmine bromide after p.o. administration in rats; subsequently, changes in blood biochemical and oxidative stress markers were measured. Pyridostigmine bromide was applied p.o. at the dose of 5.82?mg/kg b.w. according to the previously published recommendations. The absorption of pyridostigmine was relatively fast; the C_max in plasma was 110.20?±?15.12?ng/ml at T_max of 197.12?±?17.14?min. The bioavailability expressed as AUC_total was 44,348?±?7608?min ng/ml. The prolongation of pyridostigmine in circulation is in agreement with relatively long half-life that was 179.00?±?28.54?min. Several blood biochemical markers were altered, including glucose, creatinine, creatine kinase, alanine aminotransferase, aspartate aminotransferase, interleukin-6, triglycerides, and cholesterol. However, the changes could be considered as mild. Thiobarbituric acid reactive substances and ferric reducing ability of plasma indicate suppression of basal metabolism. The results of blood biochemical and oxidative stress markers imply that long-term use might possibly change the basal metabolism and cause cellular damage with inflammatory changes.