Search

Abstract: This article describes the photolysis of azithromycin, a macrolide antibiotic with reported occurrence in environmental waters, under simulated solar radiation. The photodegradation followed first-order reaction kinetics in five matrices examined. In HPLC water, the degradation rate was the slowest (half-life: 20h), whereas in artificial freshwater supplemented with nitrate (5mgL−1) or humic acids (0.5mgL−1) the degradation of azithromycin was enhanced by factors of 5 and 16, respectively, which indicated the role of indirect photolysis involving the formation of highly reactive species. Following chromatographic separation on a UPLC system, the characterization of the transformation products was accomplished using high-resolution QqToF-MS analysis. The presence of seven photoproducts was observed and their formation was postulated to originate from (bis)-N-demethylation in the desosamine sugar, O-demethylation in the cladinose sugar, combinations thereof, as well as from hydrolytic cleavages of the desosamine and/or cladinose residue. Two of these photoproducts could also be detected in natural photodegradation process in river water which was spiked with azithromycin. [Copyright &y& Elsevier]

In the environment, organic micropollutants such as pharmaceuticals can be degraded via various biotic and abiotic transformation routes. In surface waters, for example, photodegradation may constitute a relevant natural attenuation process for drug residues that have been discharged from sewage treatment facilities. In the present work, the photochemical fate of the prodrug enalapril (376 Da, C20H28N2O5) and its active metabolite enalaprilat (348 Da, C18H24N2O5), a hypotensive cardioprotector previously reported to occur in contaminated rivers, was investigated in aqueous media under the influence of irradiation generated by a sunlight simulator. The experiments yielded three detectable photodegradates for enalapril (346 Da, 2 × 207 Da) whereas the photolysis of enalaprilat went hand in hand with the intermittent buildup of one photodegradate (304 Da). Fragmentation patterns of the parent compounds were established on a hybrid quadrupole-linear ion trap-mass spectrometer exploiting its MS³ capabilities. Accurate mass measurements recorded on a hybrid quadrupole-lime-of-flight instrument in MS/MS mode allowed us to propose elemental compositions for the molecular ions of the degradates (346 Da, C19H26N2O4 207 Da, C12H17NO2 304 Da, C17H24N2O3) as well as of their fragment ions. Based on these complementary data sets from the two distinct mass spectrometric instruments, plausible structures were postulated for the four photodegradates. The compounds formed by enalapril corresponded to the loss of formaldehyde out of the proline residue (346 Da), cleavage of the central amide bond (207 Da) followed by migration of the ethylester side chain (207 Da) while decarboxylation of the free carboxylic acid was described for enalaprilat (304 Da). The study emphasized the potential of sunlight for breaking down an environmentally relevant drug and its metabolite. [ABSTRACT FROM AUTHOR]

The inadequate response of immune cells to circulating apoptotic products, such as nucleosomal DNA fragments, is assumed to be a potent stimulus for the production of autoantibodies during the pathogenesis and progression of systemic lupus erythematosus (SLE). Here, we analyzed the levels of circulating nucleosomes, caspases, and C-reactive protein in sera of 244 individuals with various autoimmune diseases (155 with autoimmune hepatic disorders, 25 with ANCA-associated vasculitis, and 64 with various connective tissue diseases), and 32 healthy controls. Nucleosomes and caspase activities were significantly elevated in sera of patients with hepatic autoimmune diseases, connective tissue diseases, and particularly in ANCA-associated vasculitis when compared with healthy individuals. Nucleosomes showed a correlation with caspases, and caspases with C-reactive protein, but nucleosomes did not correlate with C-reactive protein. Serum levels of the apoptotic products, nucleosomes, and caspases are increased in various autoimmune diseases but may not be solely responsible for antinucleosome antibody production in SLE patients. It remains to be clarified whether qualitative changes in nucleosomes are linked with pathogenesis and disease progression in SLE. [ABSTRACT FROM AUTHOR]

Identification of degradation products of environmental contaminants is a challenging task because not only are they present in very low concentrations but they are also mixed with complex matrixes that interfere with detection. This work illustrates a simple approach using ion trap mass spectrometry combined with H/D-exchange experiments to elucidate the structures of iopromide metabolites formed during biodegradation in activated sludge. Iopromide is an X-ray contrast agent that has been detected frequently in effluents of wastewater treatment plants and in surface waters due to its persistence and high usage. Three metabolites produced by oxidation of the primary alcohols (forming carboxylates) on the side chains of iopromide were identified in a batch reactor with mixed liquor from a conventional activated sludge. Derivatization of the carboxylic acid to form a methyl ester and interpretation of the MS² data of this derivative aided in the confirmation of the identities of these metabolites. Furthermore, one metabolite formed by dehydroxylation at the two side chains was identified in a batch reactor with mixed liquor from a nitrifying activated sludge. The MS² fragmentation pattern of iopromide and its metabolites revealed that the iodinated ring remains intact and that minor transformations in the structure occur during biodegradation of iopromide in biological wastewater treatment plants. [ABSTRACT FROM AUTHOR]

A study was conducted to examine the influence of hydraulic retention time (RAT) and solid retention time (SRI) on the removal of tetracycline in the activated sludge processes. Two lab-scale sequencing batch reactors (SBRs) were operated to simulate the activated sludge process. One SBR was spiked with 250 ¦g/L tetracycline, while the other SBR was evaluated at tetracycline concentrations found in the influent of the wastewater treatment plant (WWTP) where the activated sludge was obtained. The concentrations of tetracyclines in the influent of the WWTP ranged from 0.1 to 0.6 μg/L. Three different operating conditions were applied during the study (phase 1-HRT: 24 h and SRI: 10 days; phase 2-HRT: 7.4 h and SRI: 10 days; and phase 3-HRT: 7.4 h and SAT: 3 days). The removal efficiency of tetracycline in phase 3 (78.4 ± 7.1%) was significantly lower than that observed in phase 1 (86.4 ± 8.7%) and phase 2 (85.1 ± 5.4%) at the 95% confidence level. The reduction of SAT in phase 3 while maintaining a constant HRT decreased tetracycline removal efficiency. Sorption kinetics reached equilibrium within 24 h. Batch equilibrium experiments yielded an adsorption coefficient (Kads) of 8400 ± 500 mL/g and a desorption coefficient (Kdes) of 22 600 ± 2200 mL/g. No evidence of biodegradation for tetracycline was observed during the biodegradability test and sorption was found to be the principal removal mechanism of tetracycline in activated sludge. [ABSTRACT FROM AUTHOR]

In this work, the identification of two microbial degradation products of the antimicrobial trimethoprim (290 Da) is described. The structural elucidation of the metabolites, which were produced by nitrifying activated sludge bacteria in a small-scale laboratory batch reactor, was accomplished by electrospray ionization—ion trap mass spectrometry conducting consecutive fragmentation steps (MSn) combined with H/D-exchange experiments. Although one metabolite corresponded to α-hydroxytrime- thoprim (306 Da), oxidation of the aromatic ring within the diaminopyrimidine substructure was determined for the second degradate (324 Da). Accurate mass measurements of the two metabolites were provided by a hybrid quadrupole time-of-flight-mass spectrometer operated in MS/MS mode. With absolute mass errors of <5 mDa, it allowed us to confirm the proposed elemental composition for the protonated precursor ions as well as for a series of fragment ions that were previously identified by ion trap mass spectrometry. The study emphasized the potential of nitrifying activated sludge bacteria for breaking down an environmentally relevant pharmaceutical that is otherwise poorly degradable by a bacterial community encountered in conventional activated sludge. [ABSTRACT FROM AUTHOR]

Abstract: A novel procedure was developed for the simultaneous determination of linear alkylbenzene sulfonates (LAS) and their major metabolites, sulfophenyl carboxylates (SPC), in sludge-amended soil. After pressurised liquid extraction with methanol/water (90:10) and a clean-up on C18 solid-phase extraction cartridges, final analysis was done by ion-pair liquid chromatography–electrospray–tandem mass spectrometry (LC–ESI–MS/MS). With this method, SPC with 5–13 carbon atoms in the aliphatic side chain were identified for the first time in agricultural soils treated with sewage sludge. Quantification of LAS and SPC in soil from 10 field sites, which differed in the history of sludge application, gave total concentrations of 120–2840μgkg−1 for LAS and of 4–220μgkg−1 for SPC. The data provided evidence for rapid biodegradation of LAS in the initial phase after sludge amendment with a transitory build-up of high concentrations of, mainly, short-chain SPC. Trace amounts of residual LAS and SPC were detected in soils having received the last sludge treatment 10 days to 4 years prior to sampling. [Copyright &y& Elsevier]

In the present work, a photoproduct of chlortetracycline (CTC) was identified for the first time in hog lagoon samples from confined animal feeding operations. Screening of several samples by LC/ESI-MS indicated the presence of a potential photooxygenation product of CTC with a nominal mass that was 32 Da higher than the parent drug. Generation of this assumed photoproduct (designated MS 10) was achieved in a 24-h irradiation experiment of an oxygenated alkaline medium containing 50 mg L-1 CTC. Accurate mass measurements with an ESI-TOF-MS of the protonated isomerization product of CTC (iCTC) and the postulated photooxygenation product, bearing two oxygen atoms more than iCTC, were m/z 479.1229 and 511.1109, respectively. These corresponded to errors of -2.8 ppm for iCTC and +1.0 ppm for M510 relative to the theoretical masses. The generation of second-and third-stage mass spectra in an ESI-ion trap-MS showed similar characteristic fragmentation patterns for iCTC and the photoproduct M510, leading to the conclusion that the M510 structure consisted of an iCTC-like skeleton bearing two additional hydroxy groups. The site and configuration of one hydroxylation was confidently assigned, while the position of the other hydroxy group was tentatively assigned. Comparison of the (+)-ESI-MC3 spectrum and the retention time of M510 in the sample from the irradiation experiment with those from the hog lagoon samples yielded excellent agreement, suggesting that the compounds were identical. Quantitative analysis of seven hog lagoon samples showed iCFC concentrations of 1910-15800 μg L-1, while the levels of M510 were found to be between 46 and 303 μg L-1. [ABSTRACT FROM AUTHOR]

First investigations are reported on the efficiency of individual purification steps at two waterworks to eliminate sulfophenyl carboxylates (SPC) originating from biodegradation of linear alkylbenzene sulfonate surfactant. The average SPC concentrations in the waters taken from the Llobregat river, Spain and the Rhine river, Germany amounted to 5.0 and 1.8 μg L−1, respectively. In the Spanish waterworks, neither prechlorination nor flocculation followed by rapid sand filtration had an impact. After ozonation, granular activated carbon filtration, and final chlorination the SPC level was about 2 μg L−1 in such processed drinking water. In the German waterworks already the rapid sand filtration diminished the SPC concentration by >85%. Subsequent subsoil passage resulted only in a slight elimination, but once again a slow sand filtration prior to the closing chlorination substantially removed the polar micro-pollutants down to a level of <0.05 μg L−1 SPC. [Copyright &y& Elsevier]

In Brazil more than 90% of the population are not connected to municipal wastewater treatment plants. As a consequence, surface waters receive continuously considerable amounts of untreated domestic sewage containing surfactants as a major constituent. Such polluted waters gave rise to special interest if they are used as a source for the production of drinking water. In this work, the river Rio Macacu (State Rio de Janeiro, Brazil) was monitored for the occurrence of the most widely used anionic surfactant linear alkylbenzene sulfonate (LAS) together with its main degradative product, sulfophenyl carboxylates (SPC). In order to pursue the fate of both compounds after emission into the river, samples were collected at several locations along the river bank, and analyzed applying liquid chromatography-mass spectrometry after enrichment by solid-phase extraction. The LAS concentrations ranged between 14 and 155 μg l−1 and the levels of their metabolic intermediates were found from 1.2 to 14 μg l−1. The self-purification capacity of the water was impressively demonstrated in the upper course of the river downstream of a town considered as one major discharge point, whereas in the lower course the relative constant concentrations of both analytes were detected which was explained with an overall increasing level of pollution. Furthermore, a series of drinking water samples from Nitero´i and Sa˜o Gonc¸alo, supplied by the same waterworks treating surface waters from the Rio Macacu, were taken during two sampling periods and examined for the presence of the strongly polar SPC which is suspected of by-passing the purification processes. The levels detected in the drinking water ranged between 1.6 and 3.3 μg l−1. For the analyses of drinking and surface waters the peak pattern of a selected SPC homologue composed by several positional isomers served as an indicator to describe the progression of SPC degradation occurred in the river and could be used to distinguish drinking waters of different origins. [Copyright &y& Elsevier]

However, given the high prevalence of asymptomatic patients, the imperfect sensitivity of polymerase chain reaction (PCR) assays performed at a single time point, and limited testing capacity, the true number of SARS-CoV-2 infections likely exceeds the reported one. The sensitivity- and specificity-adjusted seroprevalence for Ro-pan-Ig of all patients receiving immunotherapy at the time of serum sampling (iSP) was 1.39% (CI 0.09-2.69; approach (i)). The high rate of incidental seropositives (72.7%) including two patients on anti-CD20 treatment further highlights that a serology study may be useful for estimating the true burden of SARS-CoV-2 infection also in patients undergoing immunotherapy. Here, we investigate the seroprevalence of SARS-CoV-2 Abs among neuroimmunology outpatient clinic patients from May 14th to September 30th, 2020, by two different assays and compare it to the seroprevalence of the general population. [Extracted from the article]

Abstract: Background: 80–100% of patients with multiple sclerosis (MS) display a polyspecific, intrathecal humoral immune response against a broad panel of viral agents including antibodies to measles, rubella and varicella zoster virus as its three most abundant components (called MRZ reaction [MRZR]). However, a positive MRZR reaction can also be found in some patients with CNS vasculitis, another rare autoimmune condition, raising the question whether this marker is really of high specificity for MS as previously claimed or whether it just represents a non-specific marker of CNS autoimmunity. Besides MS and CNS vasculitis, paraneoplastic neurological disorders (PND) represent the best recognized models of CNS autoimmunity. Objective: To investigate MRZR for the first time in patients with PND. Patients and methods: Forty-two patients with MS and 34 with PND were compared in this study. The intrathecal synthesis of antibodies against measles, rubella, and varicella zoster virus was detected by calculation of the respective antibody indices (AI). Results: A positive MRZ reaction as defined by a combination of at least two positive AIs was present in 37/42 patients with MS, but in none of the patients with PND (p < 0.0001). Median AI values differed significantly between groups (p < 0.0005). Conclusions: Our results confirm that MRZR is not a general marker of CNS autoimmunity. Taking into account the very rarity of CNS vasculitis as well the lack of MRZR positivity in infectious inflammatory CNS conditions as previously demonstrated, MRZR might indeed be a promising marker of MS. Further investigations on MRZR in more rare autoimmune conditions, which were not available for analysis in this study, are now warranted to refine further the specificity of this parameter. [Copyright &y& Elsevier]

The article discusses a study on whether there is a need to screen N-methyl-D-aspartate receptor antibody in patients with ovarian teratomas and without symptoms of autoimmune encephalitis. Topics mentioned include the link between NMDAR encephalitis and OT, a recommendation on the need to exclude the presence of OT in patient with NMDAR encephalitis, and the improvement of clinical management of OT patients after screening for elevated NMDAR antibodies.

Objectives: During the COVID-19 pandemic, SARS-CoV-2 antibody testing has been suggested for (1) screening populations for disease prevalence, (2) diagnostics, and (3) guiding therapeutic applications. Here, we conducted a detailed clinical evaluation of four Anti-SARS-CoV-2 immunoassays in samples from acutely ill COVID-19 patients and in two negative cohorts. Methods: 443 serum specimens from serial sampling of 29 COVID-19 patients were used to determine clinical sensitivities. Patients were stratified for the presence of acute respiratory distress syndrome (ARDS). Individual serum specimens from a pre-COVID-19 cohort of 238 healthy subjects and from a PCR-negative clinical cohort of 257 patients were used to determine clinical specificities. All samples were measured side-by-side with the Anti-SARS-CoV-2-ELISA (IgG), Anti-SARS-CoV-2-ELISA (IgA) and Anti-SARS-CoV-2-NCP-ELISA (IgG) (Euroimmun AG, Lübeck, Germany) and the Elecsys Anti-SARS-CoV-2 ECLIA (Roche Diagnostics International, Rotkreuz, Switzerland). Results: Median seroconversion occurred earlier in ARDS patients (8–9 days) than in non-ARDS patients (11–17 days), except for EUR N-IgG. Rates of positivity and mean signal ratios in the ARDS group were significantly higher than in the non-ARDS group. Sensitivities between the four tested immunoassays were equivalent. In the set of negative samples, the specificity of the Anti-SARS-CoV-2-ELISA (IgA) was lower (93.9%) compared to all other assays (≥98.8%) and the specificity of Anti-SARS-CoV-2-NCP-ELISA (IgG) was lower (98.8%) than that of Elecsys Anti-SARS-CoV-2 (100%). Conclusions: Serial sampling in COVID-19 patients revealed earlier seroconversion and higher signal ratios of SARS-CoV-2 antibodies as a potential risk marker for the development of ARDS, suggesting a utility for antibody testing in acutely diseased patients. [ABSTRACT FROM AUTHOR]

Vitamin deficiency syndromes and blood–brain barrier (BBB) dysfunction are frequent phenomena in psychiatric conditions. We analysed the largest available first-episode schizophrenia-spectrum psychosis (FEP) cohort to date regarding routine cerebrospinal fluid (CSF) and blood parameters to investigate the association between vitamin deficiencies (vitamin B12 and folate) and BBB impairments in FEP. We report a retrospective analysis of clinical data from all inpatients that were admitted to our tertiary care hospital with an ICD-10 diagnosis of a first-episode F2x (schizophrenia-spectrum) between January 1, 2008 and August 1, 2018 and underwent a lumbar puncture, blood-based vitamin status diagnostics and neuroimaging within the clinical routine. 222 FEP patients were included in our analyses. We report an increased CSF/serum albumin quotient (Qalb) as a sign of BBB dysfunction in 17.1% (38/222) of patients. White matter lesions (WML) were present in 29.3% of patients (62/212). 17.6% of patients (39/222) showed either decreased vitamin B12 levels or decreased folate levels. No statistically significant association was found between vitamin deficiencies and altered Qalb. This retrospective analysis contributes to the discussion on the impact of vitamin deficiency syndromes in FEP. Although decreased vitamin B12 or folate levels were found in approximately 17% of our cohort, we found no evidence for significant associations between BBB dysfunction and vitamin deficiencies. To strengthen the evidence regarding the clinical implications of vitamin deficiencies in FEP, prospective studies with standardized measurements of vitamin levels together with follow-up measurements and assessment of symptom severity in addition to CSF diagnostics are needed. [ABSTRACT FROM AUTHOR]

Background: Myositis-associated antibodies (MAA) and myositis-specific antibodies (MSA) are detected in patients with idiopathic inflammatory myopathies (IIM); their role as diagnostic biomarkers is however still debated. The aim of our study was to assess the utility of MAA/MSA assessed by new line immunoassays in detecting myositis among neuromuscular patients. Methods: We retrospectively analysed sera samples obtained from patients tested for myositis antibodies with the "Euroline: Autoimmune Inflammatory Myopathies 16Ag" and "myositis profile 3" kits (Mi-2, TIF1γ, MDA5, NXP2, SAE1, Jo-1, SRP, PL-7/12, EJ, OJ, Ro-52, Ku, PM-Scl75/100). First symptom, CK, EMG, muscle biopsy and diagnosis were also analysed. Using logistic regression analysis, two diagnostic models were built to evaluate the diagnostic power of MAA/MSA in distinguishing myositis patients from controls and other myopathies. Results: 1229 patients were identified. 141 patients had a bioptic confirmed IIM; other diagnoses included: myopathy (n = 357), other neuromuscular diseases (n = 144) and no neuromuscular diseases (n = 587). The specificity was 95% for MSA and 89% for MAA, the sensitivity 20% and 22%, respectively. MAA showed no use in differentiating myositis patients from controls, whereas MSA had limited effect (OR = 5.165), compared to other variables as EMG (OR = 47.755) or CK > 2000 U/L (OR = 45.307). MSA were, however, the most useful parameter differentiating IIM from non-IIM patients (OR = 7.259), better than CK > 2000 U/L (OR = 4.033) and MAA (OR = 2.737). Conclusions: Line immunoassays for myositis antibodies show high specificity but low sensitivity. Their usefulness as diagnostic biomarkers widely depends on the clinical settings. Our study suggests that MSA/MAA should be used for confirmatory and differential diagnosis rather than for screening purposes in inflammatory myopathies. [ABSTRACT FROM AUTHOR]

Pruritus is a major symptom of several dermatological diseases but has limited therapeutic options available. Animal models replicating the pathophysiology of pruritus are needed to support the development of new drugs. Induction of pruritus by chloroquine ( CQ) in mice is widely used, although, as with similar models, it has low throughput and does not distinguish between antipruritic effects and confounding factors such as sedation. To overcome these issues, we incorporated into the model an automated system that measures both scratching and locomotor behaviour simultaneously. We combined this system with the determination of CQ levels in different tissues to understand the impact of the route of CQ administration on the pruritogenic response. We concluded that whereas oral CQ does not induce pruritus due to insufficient skin levels, the bell-shaped curve of pruritus observed following subcutaneous administration is due to toxicity at high doses. We validated the model with several drugs currently used in humans: nalfurafine, aprepitant, cyproheptadine and amitriptyline. By comparing the effects of the drugs on both scratching and locomotor activity, we concluded that nalfurafine and aprepitant can exhibit efficacy at doses devoid of central effects, whereas central effects drove the efficacy of the other two drugs. This was further confirmed using non-brain-penetrant drugs. Moreover, as anticipated, anti-inflammatory drugs showed no efficacy. In conclusion, the use of an automated integrated behavioural assessment in CQ-induced pruritus makes the assay suitable for screening purposes and allows for a correct interpretation of the antipruritic effect of the compounds evaluated. [ABSTRACT FROM AUTHOR]

Polymers are used in high amounts in a wide range of applications from biomedicine to industry. Because of the growing awareness of the increasing amounts of plastic wastes in the aquatic environment during recent years, the evaluation of their biodegradability deserves special attention. In the past, most efforts were dedicated to studying the biodegradation of polyesters in soil and compost, while very little research has been conducted on their fate in wastewater. Here, we assessed the ability of bacterial communities residing in the aerobic and denitrification tank from a wastewater treatment plant (WWTP) to degrade the polymeric ester polycaprolactone diol (PCLD; average molecular weight of 1250 Da). Following the incubation of the solid polymer in WWTP tanks, matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) was used to provide evidence for hydrolytic reactions and to study differences in the spatial degradation on the PCLD surface. It was demonstrated that regardless of the wastewater type, the chemical structure on the PCLD surface underwent modifications after 7 days of exposure. Apart from the parent PCLD peak series in MALDI-MSI mass spectra, the presence of a second oligomer series with mass peaks spaced by m/ z 114 (as in PCLD) was observed. It was proposed to correspond to polycaprolactone (PCL) originating from the hydrolytic cleavage of the diethylene glycol from PCLD. Their ion masses were detected at m/ z 104 below the PCLD peaks and their structures were proposed as PCL cyclized oligomers. Differences in the spatial distribution of low MW ions (<800) between the aerobic and denitrifying exposed samples in MALDI MSI were also noticeable. While the ions at m/ z 221.1, 247.1 and 449.2 predominated in the aerobic exposed sample, those at m/ z 475.5 and 677.4 were characteristic of the denitrifying one. The MALDI-MSI measurements in the low mass range were complemented with LC-HRMS analysis to determine plausible structures of the major degradation products. Ten transformation products (TPs) were detected in the denitrifying wastewater experiment, five of them were the result of ester hydrolysis forming caprolactone oligomers (TPs 220, 334, 448, 562, and 676) while the other series corresponded to formation of PCL chain with a terminal diethylene glycol, likewise formed by ester hydrolysis (TPs 246, 360, 474, 588, and 702). [ABSTRACT FROM AUTHOR]

The widespread occurrence of pharmaceuticals in the aquatic environment has raised concerns about potential adverse effects on exposed wildlife. Very little is currently known on exposure levels and clearance mechanisms of drugs in marine fish. Within this context, our research was focused on the identification of main metabolic reactions, generated metabolites, and caused effects after exposure of fish to carbamazepine (CBZ) and ibuprofen (IBU). To this end, juveniles of Solea senegalensis acclimated to two temperature regimes of 15 and 20 °C for 60 days received a single intraperitoneal dose of these drugs. A control group was administered the vehicle (sunflower oil). Bile samples were analyzed by ultra-high-performance liquid chromatography-high-resolution mass spectrometry on a Q Exactive (Orbitrap) system, allowing to propose plausible identities for 11 metabolites of CBZ and 13 metabolites of IBU in fish bile. In case of CBZ metabolites originated from aromatic and benzylic hydroxylation, epoxidation, and ensuing O-glucuronidation, O-methylation of a catechol-like metabolite was also postulated. Ibuprofen, in turn, formed multiple hydroxyl metabolites, O-glucuronides, and (hydroxyl)-acyl glucuronides, in addition to several taurine conjugates. Enzymatic responses after drug exposures revealed a water temperature-dependent induction of microsomal carboxylesterases. The metabolite profiling in fish bile provides an important tool for pharmaceutical exposure assessment. [ABSTRACT FROM AUTHOR]

The aerobic biodegradability of four antimicrobials (sulfamethazine, sulfamethoxazole, sulfathiazole, and trimethoprim) was investigated in sewage collected at four treatment stages (primary treatment, activated sludge treatment, aerobic nitrification process, and after disinfection of treated sewage) of a municipal sewage treatment plant. The biodegradability tests were conducted in aerated batch reactors by spiking the sewage with 20 µg/L of each of the test substance. Concentration profiles of the assayed compounds were monitored during a 54-d period using liquid chromatography/electrospray ionization/mass spectrometry. Substantial differences in the degradation curves were observed between trimethoprim and the three sulfonamides. The behavior of the latter was characterized by a general biodegradability in the primary and secondary treatment. The highest degradation rates were obtained in the sewage from the activated sludge treatment, where no adaptation phase was observed. On the other hand, the onset of biodegradation in the sewage from the primary treatment was preceded by a lag phase ranging from 10 to 15 d. In contrast, trimethoprim displayed high resistance to microbial degradation in the sewage from the primary treatment and the activated sludge treatment. However, primary degradation of this compound was completed within only 3 d in the sewage from the nitrification process. [ABSTRACT FROM AUTHOR]

Liquid chromatography with an electrospray interface to a mass spectrometer (LC-ES-MS) and LC-ES coupled to a tandem MS (LC-ES-MS/MS) were used to detect and identify intermediates excreted transiently during the aerobic degradation of linear alkylbenzenesulfonates (LAS) in fixed-bed bioreactors (FBBR). The inoculum for the FBBR was the microflora of the River Rhine, Germany. Two major phenomena were observed on the addition of 100 mg/L LAS to the system, sorption and then biodegradation. Disappearance due to sorption was followed in an inhibited FBBR. Biodegradation of LAS started on day 7 and was accompanied bythe transient excretion of intermediates, which were later largely degraded. We detected not only the sulfophenylcarboxylates (SPCs) observed previously but also the alpha,beta -unsaturated SPCs (SPC-2H), which have not been reported before. Experiments with the (4-sulfophenyl)dodecanes (C12-LAS), which had minor contaminants of C11-LAS, showed C12-, C10-, C8-, C6-, and C4-SPCs when LAS was degraded as well astraces of C9-, C7-, and C5-SPCs. Signals from the SPC-2H species were usually some 10% of those from the corresponding SPCs. Samples fromthese experiments were also examined by gas chromatography-mass spectrometry (GC-MS), but no desulfonated intermediates were detected. Weinterpret the data to mean that the only attack on LAS was by omega-oxygenation; there was no visible initial desulfonation. The productsof omega-oxygenation were oxidized to the corresponding SPC and subject to beta-oxidation, as evidenced not only by the pattern of C-2 units in the excreted SPCs but also in the corresponding series of SPC-2H, representing the intermediates in beta-oxidation. [ABSTRACT FROM AUTHOR]

Abstract: This study aimed to develop and optimize a method for the extraction and analysis of moenomycin antibiotics (a.k.a. flavomycin) in corn-based feed premix and in chicken litter. Moenomycin-A was isolated from chicken litter using pressurized liquid extraction followed by a solid-phase extraction (SPE) clean-up step. The highly lipophilic nature of moenomycin necessitated the use of the less hydrophobic sorbent, C4-based SPE cartridge, and a higher temperature elution solvent, methanol at 50°C, in order to obtain satisfactory percent recoveries. After clean-up, the sample was analyzed by liquid chromatography–electrospray ionization–mass spectrometry (LC–ESI–MS). Various reversed-phase columns were examined, including C18, CN, perfluorinated C6, and a porous graphitic carbon. The set of conditions that gave the highest separation efficiency while still maintaining symmetrical peak shape was the C18 column using the H2O+0.3% HCOOH and acetonitrile mobile phase. [Copyright &y& Elsevier]

Commercial linear alkylbenzenesulfonate (LAS) contains 20 congeners of linear alkanes (C10 to C13) substituted subterminally with the 4-sulfophenyl moiety in any position from lateral to central. Parvibaculure lavamentivorans DS-1T degrades each of eight laterally substituted congeners [e.g., 2-(4-sulfophenyl)decane (2-C10-LAS); herein, compounds are named systematically by chain length (e.g., C10) and by the position of the substituent on the chain (e.g., position 2)] to a major sulfophenyl carboxylate [SPC; here 3-(4-sulfophenyl)butyrate (3-C4-SPC)] and two minor products, namely, the α,β-unsaturated SPC (SPC-2H, here 3-C4-SPC-2H) and the SPC+2C (here 5-C6-SPC) species (D. Schleheck, T. P. Knepper, K. Fischer, and A. M. Cook, Appl. Environ. Microbiol. 70:4053-4063). The degradation of centrally substituted congeners by strain DS-I was examined in this work. 5-C10-LAS yielded not only the predicted 4-C8-SPC, 4-C8-SPC-2H, and 6-C10-SPC (about 70% of products) but also sulfophenyl dicarboxylates (SPdC), i.e., C6-, C8-, and C10-SPdC. These were identified by electrospray ionization-mass spectrometry (ESI-MS) after separation by high-pressure liquid chromatography (HPLC). ESI ion-trap MS and ESI-time of flight-MS were used to confirm the identities of key intermediates. Different mixtures of congeners obtained by separation of commercial LAS by HPLC were degraded, and the degradative products were compared. If a congener carried the sulfophenyl substituent on the 5, 6, or 7 position, SPdCs were formed as well as SPC, SPC-2H, and SPC+2C, whereas the substituent on the 2, 3, or 4 position yielded only SPC, SPC-2H, and SPC+2C. Some 50 products were generated from the 20 LAS congeners: 11 major SPCs, each with an SPC-2H and an SPC+2C (i.e., 33 SPC and SPC-2H species), and about 17 SPdC species. A large array of compounds, many in low quantities, is thus generated by P. lavamentivorans DS-1 during the degradation of commercial LAS. [ABSTRACT FROM AUTHOR]

The mutagenicity of crude extracts and subfractions of two samples of a reference sewage sludge material and two sewage sludges from two wastewater treatment plants (WWTP), one urban and the other one urban mixed with industrial, was assessed using an Ames fluctuation assay based on 384-well microtiter plates with liquid cultures. Crude extracts of sludges were obtained by ultrasonic extraction with dichloromethane/methanol, and further column fractionation yielded two fractions, one of which containing mutagenic polycyclic aromatic hydrocarbons (PAHs). Quantitative analysis performed by gas chromatography-mass spectrometry gave sum concentrations of the 16 PAHs listed as priority pollutants by the U.S. Environmental Protection Agency at levels between 1,305 and 2,442 µg/kg. Subjecting crude extracts and column fractions to the mutagenicity assay with Salmonella strains TA98 and TA100 provided good qualitative correlation between the presence of mutagenic PAH and the induction of gene mutations. In general, the crude extracts and the PAH-fractions induced positive responses in the assay with both bacterial strains on metabolic activation by S9 rat-liver homogenate, whereas direct-acting mutagens were not detectable. In the assay with the real sludge samples of two different WWTPs, TA98 proved to be more sensitive than TA100; however, similar sensitivities of the tester strains were observed for two reference sewage sludge materials of the same origin. The outcomes of the Ames fluctuation assay demonstrated its performance as a cost-effective and relatively rapid screening tool to assess the genotoxic potential of complex environmental samples. [ABSTRACT FROM AUTHOR]

Background: Human encephalitis can originate from a variety of different aetiologies, of which infection is the most common one. The diagnostic work-up is specifically challenging in patients with travel history since a broader spectrum of unfamiliar additional infectious agents, e. g. tropical disease pathogens, needs to be considered. Here we present a case of encephalitis of unclear aetiology in a female traveller returning from Africa, who in addition developed an atypical herpes simplex virus (HSV) encephalitis in close temporal relation with high-dose steroid treatment.Case Presentation: A previously healthy 48-year-old female presented with confusion syndrome and impaired vigilance which had developed during a six-day trip to The Gambia. The condition rapidly worsened to a comatose state. Extensive search for infectious agents including a variety of tropical disease pathogens was unsuccessful. As encephalitic signs persisted despite of calculated antimicrobial and antiviral therapy, high-dose corticosteroids were applied intravenously based on the working diagnosis of an autoimmune encephalitis. The treatment did, however, not improve the patient's condition. Four days later, bihemispheric signal amplification in the insular and frontobasal cortex was observed on magnetic resonance imaging (MRI). The intracranial pressure rapidly increased and could not be controlled by conservative treatment. The patient died due to tonsillar herniation 21 days after onset of symptoms. Histological examination of postmortem brain tissue demonstrated a generalized lymphocytic meningoencephalitis. Immunohistochemical reactions against HSV-1/2 indicated an atypical manifestation of herpesviral encephalitis in brain tissue. Moreover, HSV-1 DNA was detected by a next-generation sequencing (NGS) metagenomics approach. Retrospective analysis of cerebrospinal fluid (CSF) and serum samples revealed HSV-1 DNA only in specimens one day ante mortem.Conclusions: This case shows that standard high-dose steroid therapy can contribute to or possibly even trigger fulminant cerebral HSV reactivation in a critically ill patient. Thus, even if extensive laboratory diagnostics including wide-ranging search for infectious pathogens has been performed before and remained without results, continuous re-evaluation of potential differential diagnoses especially regarding opportunistic infections or reactivation of latent infections is of utmost importance, particularly if new symptoms occur. [ABSTRACT FROM AUTHOR]

Cyclic nucleotide cAMP is a ubiquitous secondary messenger involved in a plethora of cellular responses to biological agents involving activation of adenylyl cyclase. Its intracellular levels are tightly controlled by a family of cyclic nucleotide degrading enzymes, the PDEs. In recent years, cyclic nucleotide phosphodiesterase type 4 (PDE4) has aroused scientific attention as a suitable target for anti-inflammatory therapy in respiratory diseases, particularly in the management of asthma and COPD. Here we describe our efforts to discover novel, highly potent inhaled inhibitors of PDE4. Through structure based design, with the inclusion of a variety of functional groups and physicochemical profiles in order to occupy the solvent-filled pocket of the PDE4 enzyme, we modified the structure of our oral PDE4 inhibitors to reach compounds down to picomolar enzymatic potencies while at the same time tackling successfully an uncovered selectivity issue with the adenosine receptors. In vitro potencies were demonstrated in a rat lung neutrophilia model by administration of a suspension with a Penn-Century MicroSprayer Aerosolizer. [ABSTRACT FROM AUTHOR]

The chemoattractant receptor-homologous molecule expressed on T-helper type 2 cells (CRTh2) is a G protein-coupled receptor expressed on the leukocytes most closely associated with asthma and allergy like eosinophils, mast cells, Th2-lymphocytes and basophils. At present it is clear that CRTh2 mediates most prostaglandin D 2 (PGD2) pro-inflammatory effects and as a result antagonists for this receptor have reached asthma clinical studies showing a trend of lung function improvement. The challenge remains to identify compounds with improved clinical efficacy when administered once a day. Herein we described the pharmacological profile of LAS191859, a novel, potent and selective CRTh2 antagonist. In vitro evidence in GTPγS binding studies indicate that LAS191859 is a CRTh2 antagonist with activity in the low nanomolar range. This potency is also maintained in cellular assays performed with human eosinophils and whole blood. The main differentiation of LAS191859 vs other CRTh2 antagonists is in its receptor binding kinetics. LAS191859 has a residence time half-life of 21 h at CRTh2 that translates into a long-lasting in vivo efficacy that is independent of plasma levels. We believe that the strategy behind this compound will allow optimal efficacy and posology for chronic asthma treatment. [ABSTRACT FROM AUTHOR]

Spleen tyrosine kinase (Syk) is essential for signal transduction of immunoreceptors. Inhibition of Syk abrogates mast cell degranulation and B cell responses. We hypothesized that Syk inhibition in the lung by inhaled route could block airway mast cells degranulation and the early asthmatic response without the need of systemic exposure. We discovered LAS189386, a novel Syk inhibitor with suitable properties for inhaled administration. The aim of this study was to characterize the in vitro and in vivo profile of LAS189386. The compound was profiled in Syk enzymatic assay, against a panel of selected kinases and in Syk-dependent cellular assays in mast cells and B cells. Pharmacokinetics and in vivo efficacy was assessed by intratracheal route. Airway resistance and mast cell degranulation after OVA challenge was evaluated in an ovalbumin-sensitized Brown Norway rat model. LAS189386 potently inhibits Syk enzymatic activity (IC 50 7.2 nM), Syk phosphorylation (IC 50 41 nM), LAD2 cells degranulation (IC 50 56 nM), and B cell activation (IC 50 22 nM). LAS189386 inhibits early asthmatic response and airway mast cell degranulation without affecting systemic mast cells. The present results support the hypothesis that topical inhibition of Syk in the lung, without systemic exposure, is sufficient to inhibit EAR in rats. Syk inhibition by inhaled route constitutes a promising therapeutic option for asthma. [ABSTRACT FROM AUTHOR]

In this study, four unapproved analogues of Sildenafil (SDF) were photodegraded under synthetic sunlight in artificial freshwater. Homosildenafil (H-SDF), hydroxyhomo-sildenafil (HH-SDF), norneosildenafil (NR-SDF) and thiosildenafil (T-SDF) were selected because they are frequently detected as adulterants in natural herbal products. Using UPLC-Orbitrap (Q Exactive)-MS, six photoproducts common to H-SDF, HH-SDF and T-SDF and nine unique transformation products of different molecular weights were identified based on their high-resolution (+)ESI product ion spectra. Mass spectral analysis of deuterated H-SDF, labeled on the N-ethyl group, allowed to gain mechanistic insight into the fragmentation pathway of the substituted piperazine ring and to support the postulated photoproduct structures. The mass spectral fragmentation confirmed the stepwise destruction of the piperazine ring eventually producing a sulfonic acid derivative (C17H20N4O5S: 392.1151 Da). In contrast, the photodegradation of NR-SDF, which lacks a piperazine ring in its structure, formed only two prominent photoproducts originating from N,N-dealkylation of the sulfonamide followed by hydrolysis. The current work constitutes the first study on the photodegradation of analogs of erectile dysfunction drugs and the first detection of two transformation products ( m/z 449 and 489) in environmental samples. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A knowledge-based design strategy led to the discovery of several new series of potent and orally bioavailable CRTh2 antagonists where a bicyclic heteroaromatic ring serves as the central core. Structure–kinetic relationships (SKR) opened up the possibility of long receptor residence times. [ABSTRACT FROM AUTHOR]

Extensive structure–activity relationship (SAR) and structure–kinetic relationship (SKR) studies in the bicyclic heteroaromatic series of CRTh2 antagonists led to the identification of several molecules that possessed both excellent binding and cellular potencies along with long receptor residence times. A small substituent in the bicyclic core provided an order of magnitude jump in dissociation half-lives. Selected optimized compounds demonstrated suitable pharmacokinetic profiles. [ABSTRACT FROM AUTHOR]

Pyrrolopiperidinone acetic acids (PPAs) were identified as highly potent CRTh2 receptor antagonists. In addition, many of these compounds displayed slow-dissociation kinetics from the receptor. Structure–kinetic relationship (SKR) studies allowed optimisation of the kinetics to give potent analogues with long receptor residence half-lives of up to 23 h. Low permeability was a general feature of this series, however oral bioavailability could be achieved through the use of ester prodrugs. [ABSTRACT FROM AUTHOR]

Abstract: In this manuscript, the synthesis and biological activity of a series of pyrazole acetic acid derivatives as CRTh2 antagonists is presented. Biological evaluation in vitro revealed that the pyrazole core showed in several cases a different structure–activity relationship (SAR) to that of related indole acetic acid. A potent series of ortho-sulfonyl benzyl substituents was found, from which compounds 27 and 63 were advanced to in vivo profiling. [Copyright &y& Elsevier]

Abstract: High throughput screening identified the pyrazole-4-acetic acid substructure as CRTh2 receptor antagonists. Optimisation of the compounds uncovered a tight SAR but also identified some low nanomolar inhibitors. [Copyright &y& Elsevier]

Abstract: Objectives: Toxic oil syndrome (TOS) is a disease that appeared in Spain in 1981. Epidemiological work traced the origin to the ingestion of aniline-adulterated rapeseed oil, fraudulently marketed and sold as edible oil. It affected more than 20,000 people with over 400 deaths in the first 2 years. In 2001 evidence was presented that genetic factors could play a role in the susceptibility of individuals to the disease. Thus, a prospective study on the differences in gene expression in sera between control versus TOS-affected populations, both originally exposed to the toxic oil, was undertaken in our laboratory. Methods: Differential protein expression was analyzed by two-dimensional electrophoresis (2-DE). Problems related with serum analysis by 2-DE were addressed to improve protein detection in the gel images. Three new commercial systems for albumin depletion were tested to optimize the detection of minor proteins. The use of nonionic reductants or the presence of thiourea in the gels, were also tested. Results: From the resulting optimized images, a group of 329 major gel spots was located, matched and compared with serum samples. Thirty-five of these protein spots were found to be under- or over-expressed in TOS patients (threefold increase or decrease). Proteins in these spots were identified by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) peptide map fingerprinting and database search. Several haptoglobin (Hp) isoforms were found to be differentially expressed, showing expression phenotypes that could be related with TOS. Resolution of the homologous α-1s and α-1f chains, with a mass difference of only 0.043Da, was obtained after guanidation of the protein with O-methylisourea. We applied this procedure to the study of the distribution of the Hp alleles HP2, HP1s and HP1f in control versus TOS-affected populations. The MALDI-TOF proteotyping method was validated by a parallel analysis of the serum samples by 2-DE. Conclusions: Data obtained from 54 TOS cases and 48 controls indicate significant differences in the distribution of Hp phenotypes in the two populations. Haptoglobin phenotypes have been reported to have biological and clinical consequences and have been described as risk factors for several diseases. Consequently, it was concluded that haptoglobin polymorphism could play a role in TOS. [Copyright &y& Elsevier]

A new method for the quantification of benzoxazinone derivatives in extracts of wheat foliage and root samples using liquid chromatography-electrospray ionizationtandem mass spectrometry (LC-ESI-MS-MS) is described. Using this method, the characterization, separation, and quantitative detection of a mixture of six naturally occurring 1,4-benzoxazin-3(4H)-one derivatives, including the hydroxamic acids (DIMBOA, DIBOA), lactams (HBOA, and HMBOA), benzoxazilinones (BOA, MBOA), and two synthetic methoxylated variations of DIBOA and HBOA, was achieved. The application of a novel, highly modified reversed-phase LC column, the dodecyl (C[sub 12]) TMS endcapped Synergi MAX-RP, enhanced the on-line chromatographic separation through improvements to component resolution, analyte stability and peak shape and also to the column lifetime. The complete ESI-MS-MS precursor-product ion fragmentation pathways for the benzoxazinone derivatives are described for the first time and used to deduce a generic fragmentation pattern for the compound class. Characteristic transitions for the benzoxazinones were thus used in the developed analytical method enabling reliable quantification with simultaneous screening for other potentially present derivatives, while eliminating interferences from other coeluting contaminants from the complex plant extract matrix. Quantitative analysis was done in the multiple reaction monitoring mode, using two specific combinations of a precursor-product ion transitions for each compound. The ESI-MS-MS detection method offered improvements to the sensitivity and selectivity, as compared with previously applied LC methods, with detection limits down to 0.002-0.023 ng/ µL. The developed method was demonstrated by analyzing foliages and roots of six different wheat cultivars using pressurized liquid extraction-solid-phase extraction cleanup-LC-ESI-MS-MS. The analytes were detected in the range of 0.7-207 µg/g of dry weight. [ABSTRACT FROM AUTHOR]

Temporary rivers become dependent on wastewater effluent for base flows, which severely impacts river ecosystems through exposure to elevated levels of nutrients, dissolved organic matter, and organic micropollutants. However, biodegradation processes occurring in these rivers can be enhanced by wastewater bacteria/biofilms. Here, we evaluated the attenuation of pharmaceuticals and their human metabolites performing retrospective analysis of 120 compounds (drugs, their metabolites and transformation products) in mesocosm channels loaded with wastewater effluents twice a week for a period of 31 days. Eighteen human metabolites and seven biotransformation products were identified with high level of confidence. Compounds were classified into five categories. Type-A: recalcitrant drugs and metabolites (diclofenac, carbamazepine and venlafaxine); Type-B: degradable drugs forming transformation products (TPs) (atenolol, sitagliptin, and valsartan); Type-C: drugs for which no known human metabolites or TPs were detected (atorvastatin, azithromycin, citalopram, clarithromycin, diltiazem, eprosartan, fluconazole, ketoprofen, lamotrigine, lormetazepam, metformin, telmisartan, and trimethoprim); Type-D: recalcitrant drug metabolites (4-hydroxy omeprazole sulfide, erythro/threo-hydrobupropion, and zolpidem carboxylic acid); Type-E: unstable metabolites whose parent drug was not detectable (norcocaine, benzolylecgonine, and erythromycin A enol ether). Noteworthy was the valsartan acid formation from valsartan with transient formation of TP-336. ga1 • Retrospective HRMS analysis of drugs, their metabolites and their TPs in mesocosm. • 18 metabolites and 7 TPs were tentatively identified and detected in real WW. • Two-step transformation of valsartan to valsartan acid in real WW from the mesocosm. • SWATH acquisition and NIST-2017 spectral library for successful retrospective analysis. [ABSTRACT FROM AUTHOR]