Development of an analytical method to quantify N-acyl-homoserine lactones in bacterial cultures, river water, and treated wastewater.

N-Acyl-homoserine lactones (AHL) play a major role in the communication of Gram-negative bacteria. They influence processes such as biofilm formation, swarming motility, and bioluminescence in the aquatic environment. A comprehensive analytical method was developed to elucidate the "chemical communication" in pure bacterial cultures as well as in the aquatic environment and engineered environments with biofilms. Due to the high diversity of AHLs and their low concentrations in water, a sensitive and selective LC-ESI-MS/MS method combined with solid-phase extraction was developed for 34 AHLs, optimized and validated to quantify AHLs in bacterial conditioned medium, river water, and treated wastewater. Furthermore, the developed method was optimized in terms of enrichment volume, internal standards, limits of detection, and limits of quantification in several matrices. An unanticipated variety of AHLs was detected in the culture media of Pseudomonas aeruginosa (in total 8 AHLs), Phaeobacter gallaeciensis (in total 6 AHLs), and Methylobacterium mesophilicum (in total 15 AHLs), which to our knowledge have not been described for these bacterial cultures so far. Furthermore, AHLs were detected in river water (in total 5 AHLs) and treated wastewater (in total 3 AHLs). Several detected AHLs were quantified (in total 24) using a standard addition method up to 7.3±1.0 µg/L 3-Oxo-C12-AHL (culture media of P. aeruginosa).

Isocitrate-dehydrogenase-mutant lower grade glioma in elderly patients: treatment and outcome in a molecularly characterized contemporary cohort.

PURPOSE: Lower-grade glioma (LGG) is rare among patients above the age of 60 ("elderly"). Previous studies reported poor outcome, likely due to the inclusion of isocitrate dehydrogenase (IDH) wildtype astrocytomas and advocated defensive surgical and adjuvant treatment. This study set out to question this paradigm analyzing a contemporary cohort of patients with IDH mutant astrocytoma and oligodendroglioma WHO grade 2 and 3. METHODS: Elderly patients treated in our department for a supratentorial, hemispheric LGG between 2009 and 2019 were retrospectively analyzed for patient-, tumor- and treatment-related factors and progression-free survival (PFS) and compared to patients aged under 60. Inclusion required the availability of subtype-defining molecular data and pre- and post-operative tumor volumes. RESULTS: 207 patients were included, among those 21 elderlies (10%). PFS was comparable between elderly and younger patients (46 vs. 54 months; p = 0.634). Oligodendroglioma was more common in the elderly (76% vs. 46%; p = 0.011). Most patients underwent tumor resection (elderly: 81% vs. younger: 91%; p = 0.246) yielding comparable residual tumor volumes (elderly: 7.8 cm3; younger: 4.1 cm3; p = 0.137). Adjuvant treatment was administered in 76% of elderly and 61% of younger patients (p = 0.163). Uni- and multi-variate survival analyses identified a tumor crossing the midline, surgical strategy, and pre- and post-operative tumor volumes as prognostic factors. CONCLUSION: Elderly patients constitute a small fraction of molecularly characterized LGGs. In contrast to previous reports, favorable surgical and survival outcomes were achieved in our series comparable to those of younger patients. Thus, intensified treatment including maximal safe resection should be advocated in elderly patients whenever feasible.

Bromination of Quorum Sensing Molecules: Vanadium Bromoperoxidase and Cerium Dioxide Nanocrystals via Free Active Bromine Transform Bacterial Communication.

The halogenation of quorum sensing molecules (QSMs) is known to be catalyzed by enzymes such as haloperoxidase (HPO) as well as cerium dioxide nanocrystals (NC), which mimic enzymes. Those enzymes and mimics can influence biological processes such as biofilm formation, where bacteria use QSMs for the "chemical" communication between each other and the coordination of surface colonization. However, not much is known about the degradation behavior of a broad spectrum of QSMs, especially for HPO and its mimics. Therefore, in this study, the degradation of three QSMs with different molecule moieties was elucidated. For this purpose, different batch experiments were carried out with HPOs, NCs and free active bromine (FAB). For N-ß-ketocaproyl-homoserine lactone (3-Oxo-C6-AHL), N-cis-tetradec-9Z-enoyl-homoserine lactone (C14:1-AHL) and 2-heptyl-4-quinolone (HHQ) a fast degradation and moiety-specific transformations were observed. The HPO vanadium bromoperoxidase as well as cerium dioxide NCs catalyzed the formation of the same brominated transformation products (TPs). Since the same TPs are formed in batch experiments with FAB it is very likely that FAB is playing a major role in the catalytical reaction mechanism leading to the transformation of QSMs. In this study in total 17 TPs could be identified in different levels of confidence and the catalytic degradation processes for two QS groups (unsaturated AHLs and alkyl quinolones) with cerium dioxide NCs and vanadium bromoperoxidase were expanded.

Improvement of functional outcome for patients with newly diagnosed grade 2 or 3 gliomas with co-deletion of 1p/19q - IMPROVE CODEL: the NOA-18 trial.

BACKGROUND: Given the young age of patients with CNS WHO grade 2 and 3 oligodendrogliomas and the relevant risk of neurocognitive, functional, and quality-of-life impairment with the current aggressive standard of care treatment, chemoradiation with PCV, of the tumour located in the brain optimizing care is the major challenge. METHODS: NOA-18 aims at improving qualified overall survival (qOS) for adult patients with CNS WHO grade 2 and 3 oligodendrogliomas by randomizing between standard chemoradiation with up to six six-weekly cycles with PCV and six six-weekly cycles with lomustine and temozolomide (CETEG) (n = 182 patients per group accrued over 4 years) thereby delaying radiotherapy and adding the chemoradiotherapy concept at progression after initial radiation-free chemotherapy, allowing for effective salvage treatment and delaying potentially deleterious side effects. QOS represents a new concept and is defined as OS without functional and/or cognitive and/or quality of life deterioration regardless of whether tumour progression or toxicity is the main cause. The primary objective is to show superiority of an initial CETEG treatment followed by partial brain radiotherapy (RT) plus PCV (RT-PCV) at progression over partial brain radiotherapy (RT) followed by procarbazine, lomustine, and vincristine (PCV) chemotherapy (RT-PCV) and best investigators choice (BIC) at progression for sustained qOS. An event concerning a sustained qOS is then defined as a functional and/or cognitive and/or quality of life deterioration after completion of primary therapy on two consecutive study visits with an interval of 3 months, tolerating a deviation of at most 1 month. Assessments are done with a 3-monthly MRI, assessment of the NANO scale, HRQoL, and KPS, and annual cognitive testing. Secondary objectives are evaluation and comparison of the two groups regarding secondary endpoints (short-term qOS, PFS, OS, complete and partial response rate). The trial is planned to be conducted at a minimum of 18 NOA study sites in Germany. DISCUSSION: qOS represents a new concept. The present NOA trial aims at showing the superiority of CETEG plus RT-PCV over RT-PCV plus BIC as determined at the level of OS without sustained functional deterioration for all patients with oligodendroglioma diagnosed according to the most recent WHO classification. TRIAL REGISTRATION: Clinicaltrials.gov NCT05331521 . EudraCT 2018-005027-16.

Cement pastes containing air entraining agent release the biocide octylisothiazolinone posing ecotoxicological effects.

We investigated whether cement pastes are a possible source of ecotoxicologically potent substances. For this purpose, leaching according to DIN EN 16637-2 was performed on portland cement pastes as well as blast furnace slag cement with and without an air entraining agent (AEA). The AEA, consisting of wood rosin and resin, contained the stabiliser drometrizole and the biocide octylisothiazolinone (OIT), which was confirmed by our non-target screening (NTS). Our ecotoxicological studies (Daphnia magna, Aliivibrio fischeri and Desmodesmus subspicatus) of the pure cement eluates showed no effects at all. In these samples, it was possible to attribute up to 85 % of the dissolved organic carbon (DOC) to acetate, formate and diethylene glycol (DiEG). Eluates from cement pastes with AEA contained up to 70 µg/L octylisothiazolinone (OIT), and no drometrizole was found. Around 90 % of the total OIT release happened within the first 6 h. It was possible to attribute the observed ecotoxicological effects mainly to the OIT concentrations. Additional leaching with elevated sulphate concentrations (800 mg/L) did not influence the release of DOC and OIT or increase the ecotoxicological effects. As a consequence, we advise curing the cement paste for 24 h prior to use, as this largely avoids the release of OIT and the observed ecotoxicological effects.

Implications of biological activated carbon filters for micropollutant removal in wastewater treatment.

Granulated Activated Carbon (GAC) filtration is a common process for advanced wastewater treatment. In such filters, the removal of organic substances results from adsorptive as well as biological processes. This work investigated the potential of biological processes and their influence on GAC-filter performance. During 32 months, the removal of micropollutants,Dissolved Organic Carbon (DOC) and the spectral absorption coefficient was monitored in six GAC-filters. The effects of pre-treatment (cloth- and/or membrane-filtration), EBCT (from 6 - 35 min) and GAC-type were evaluated. Likewise, the impact of the influent´s fluctuations in temperature, flow and concentration (ammonia, nitrate, and soluble reactive phosphorus (sRP)) were analysed. Biological processes were tracked by the frequency of backwashing, oxygen consumption, removal of poorly absorbable micropollutants and production of transformation products. Pre-treatment influenced biofilm growth significantly. Membrane filtration delayed the first backwashing event by 122 d in comparison to cloth-filtration, where the first backwash was conducted after only 21 d. Removal of poorly absorbable substances was observed early on (40 - 50 d). Parallel operation contributed to a better utilisation of the GAC-capacity and the biological removal potential. Influent nitrogen species > 0.5 mg N/L promoted biofilm growth, whereas sRP seemed to have no effect. The developed biofilm and optimal operating conditions led to longer life spans of the GAC-filters, making carbon usage rates comparable to those from PAC applications. The results suggest that biological processes accounted for about 25 - 42% of the totally removed DOC at the end of the operation.

Empty bed contact time: The key for micropollutant removal in activated carbon filters.

The removal of micropollutants from wastewater is an emerging issue that currently concerns the wastewater sector the most. Granular Activated Carbon (GAC) has gained recognition as a suitable technology for dealing with this problem. This study assesses the performance of six GAC-filters for the removal of micropollutants installed as final treatment step at a municipal wastewater treatment plant. The influence of the GAC-type and the Empty Bed Contact Time (EBCT) on the filter performance was evaluated. The breakthrough behaviour of 13 selected micropollutants as well as the removal of the Dissolved Organic Carbon (DOC) and UV absorption at 254 nm were investigated. Besides, the adsorbed DOC (qDOC) was introduced as assessment parameter (adsorbed and biodegraded DOC), instead of the commonly used treated bed volume. Finally, Size Exclusion Chromatography (SEC) with online DOC and UV254nm detection was applied for a better understanding of the influent and effluent characteristics. The results showed that the pore size distribution is a crucial feature of the activated carbon. A balanced proportion of macro-, meso­ and micropores may play a role in the better removal of micropollutants in presence of DOC. Regardless of the GAC-type, a minimum EBCT between 20 - 30 min was necessary. We proved that a short EBCT would not fully use the sorption capacity, whereas a long EBCT would increase the carbon demand without improving of the removal. Lastly, according to the SEC results, after a short operation time no difference between the influent and effluent chromatographable fractions (DOC and UV254nm) was observed.

Elucidation of removal processes in sequential biofiltration (SBF) and soil aquifer treatment (SAT) by analysis of a broad range of trace organic chemicals (TOrCs) and their transformation products (TPs).

Many chemicals with different physico-chemical properties are present in municipal wastewater. In this study, the removal of a broad range of trace organic chemicals (TOrCs) was determined in two biological treatment processes differing in hydraulic retention time: sequential biofiltration (SBF) and soil-aquifer treatment (SAT), operated in Germany and Spain. Occurrence and the degree of removal of more than 150 TOrCs with different physico-chemical properties were analysed, including precursors as well as human metabolites and environmental transformation products (TPs). Ninety TOrCs were detected in the feed water of the SBF system, 40% of these showed removal efficiencies of higher than 30% during biological treatment. In SAT, 70 TOrCs were detected in the feed water, 60% of these could be reduced by more than 30% after approximately 3 days of subsurface treatment. For uncharged and negatively charged TOrCs biological degradation was mainly responsible for the removal, while positively charged TOrCs were most likely also removed by ionic interactions. The detections of TPs confirmed that biodegradation was a major removal process in both systems. The analysis of positively and negatively charged, neutral and zwitterionic TOrCs and the simultaneous analysis of precursors and their biologically formed TPs enabled a detailed understanding of underlying mechanisms of their removal in the two systems. On this basis, criteria for site-specific indicator selection were proposed.

[Non-muscle-invasive bladder cancer: Information transfer from the clinic to the doctor's office : Results of a questionnaire study and presentation of a software solution]. / Nicht muskelinvasives Harnblasenkarzinom: Risikostratifizierung und Befundweitergabe : Ergebnisse einer Fragebogenstudie und Vorstellung einer Softwarelösung.

BACKGROUND AND OBJECTIVES: The adjuvant treatment of non-muscle-invasive bladder cancer (NMIBC) is based on the individual risk profile (RP) and its sufficient transfer from the clinic to the doctor's office. The objectives of our study were to verify the importance and degree of transfer of RP and recommendation for risk-adapted adjuvant treatment (RAAT) in patients with NMIBC as well as to develop appropriate tools for this purpose, if necessary. MATERIALS AND METHODS: An email-based survey distributed to urologists in Brandenburg, Berlin, Bavaria and Lower Saxony explored the questions mentioned above. In addition, a tool for risk stratification and information transfer for patients with NMIBC was developed and validated. RESULTS: From a total of 134 questionnaires analyzed, 55 were from clinic urologists (CUs) and 79 were from ambulant urologists (AUs). Although 9 out of 10 urologists considered the RP of importance, only 29 % of CUs and 24 % of AUs (p = 0.553) confirmed that the RP was always mentioned in medical reports. The recommendation for RAAT was confirmed from 62 % of CUs and 20 % of AUs (p < 0.001). A recommendation for RAAT in the medical report was requested by 86 % of AUs. The risk calculator presented here - to our knowledge the first with integration of the 2004 WHO grading - is delivered in all mathematically possible constellations a RP, according to guideline recommendations. CONCLUSION: Urologists in the clinic and doctor's office both attach considerable importance to the determination and transfer of RP and the recommendation for RAAT. There was evidence to suggest an overestimation of the quality of medical reports by the CU. The risk calculator provides an easy and cost-neutral option to improve risk stratification and information transfer from the clinic to the doctor's office.

[Results of a Questionnaire-Based Study on Guideline Adherence Regarding Adjuvant Treatment Recommendations for Patients with Non-Muscle-Invasive Bladder Cancer: Just a Disturbing Sidelight?]. / Ergebnisse einer Fragebogenstudie zur Leitlinienadhärenz der adjuvanten Therapieempfehlungen für Patienten mit nicht-muskelinvasivem Harnblasenkarzinom - nur ein beunruhigendes Streiflicht?

BACKGROUND: The EAU guidelines on non-muscle-invasive bladder cancer (NMIBC) provide for risk stratification in low, intermediate and high risk based on infiltration depth, grading, concomitant carcinoma in situ, recurrence status, focality and tumour size. The aim of this study was to evaluate guideline adherence regarding risk stratification and risk-adapted treatment recommendations in NMIBC. MATERIAL AND METHODS: An email-based survey distributed over the urological professional associations of Berlin, Brandenburg, Bremen, Hamburg, Mecklenburg-Western-Pomerania, Lower Saxony and Schleswig-Holstein assessed field of activity (doctor's office vs. clinic) and the presence of the additional qualification "Medical Tumour Therapy" (aqMtt). Also it inquired about the tools used for risk stratification in NMIBC. Finally, 3 scenarios were given, 2 of them corresponding to high-risk NMIBC and one corresponding to intermediate-risk NMIBC. Respondents were asked to provide a treatment recommendation. The results were presented comparatively for field of activity (doctor's office vs. clinic) and presence of aqMtt. RESULTS: 74 responses were received (response rate of 12.3%). 57 (77.0%) of respondents had aqMtt. 52 (70.3%) worked in doctor's offices or medical care centres, 12 (16.2%) in a urology clinic, and for 10 (13.5%) respondents this information was lacking. The most frequently used tool for risk stratification was the EAU guideline. Accordingly, treatment recommendations for the three scenarios were considered to be correct if according to EAU guideline. In high-risk NMIBC, an average 29.3% (19.3-37.5%) of adequate treatment recommendations were made depending on the comparison group. An average of 69.8% (62.5-77.2%) and 0.9% (0.0-3.9%) treatment recommendations would lead to under- or overtreatment, respectively. The corresponding values for intermediate-risk NMIBC were 56.8% (52.6-62.5%) for adequate treatment, 43.2% (37.5-47.4%) for undertreatment and 0.0% for overtreatment. Field of activity and the presence of aqMtt had no significant impact on the accuracy of treatment recommendations. CONCLUSION: The results of our survey provide strong evidence of poor guideline adherence with a consecutive risk for undertreatment of patients with NMIBC. This requires joint efforts of all those involved in the treatment of NMIBC to improve quality of care.

Bicyclic imidazo derivatives, a new class of highly selective inhibitors for the human immunodeficiency virus type 1.

In the search for new antiviral agents against human immunodeficiency virus, different members of two imidazoheterocycle families (imidazothiazoles, imidazopyridines) have been found to display potent inhibitory effects on the replication of HIV-1. Three of these derivatives, which show significant anti-HIV-1 activity, have been chosen for further studies. The analysis of these compounds and their comparison to AZT and TIBO revealed that these bicyclic imidazo derivatives represent a class of highly specific inhibitors of HIV-1, but not of HIV-2 or simian immunodeficiency virus (SIV). Their inhibition of HIV-1 is mediated through interaction with the reverse transcriptase (RT). The mechanism of action of these bicyclic imidazo derivatives may be similar to that of the other non-nucleoside RT inhibitors (NNRTIs).

High affinity [3H]zolpidem binding in the rat brain: an imidazopyridine with agonist properties at central benzodiazepine receptors.

[3H]Zolpidem, a novel hypnotic drug possessing a chemical structure unrelated to that of benzodiazepine (BZD) was employed as a new ligand to determine its binding characteristics to membrane preparations of rat cerebral cortex and cerebellum. In both structures, the imidazopyridine [3H]zolpidem bound with high affinity to a single population of recognition sites. The cerebellum possessed a similar number of [3H]zolpidem and [3H]diazepam binding sites, while the cerebral cortex possessed a lower density of [3H]zolpidem than [3H]diazepam binding sites. In contrast to [3H]diazepam binding, [3H]zolpidem binding was not detectable in the spinal cord. In the cortex, BZDs had a similar potency to displace [3H]zolpidem and [3H]diazepam binding while non-BZDs were more potent to inhibit [3H] zolpidem binding than [3H]diazepam binding. The binding of [3H]zolpidem was enhanced by GABA to the same extent as [3H]diazepam binding. The increase in [3H] zolpidem binding caused by chloride ions was less pronounced than that in [3H]diazepam binding. It is concluded that [3H]zolpidem possesses selectivity for BZD receptors with the pharmacological characteristics and regional distribution of the BZD1 receptor subtype. [3H]Zolpidem as a radioligand offers a useful additional tool to study the mechanism of action of hypnotics acting through BZD receptor subtypes.

Adjuvant chemoimmunotherapy with LMF plus BCG in node-negative and node-positive breast cancer - intermediate report at 4 years.

A randomized surgical adjuvant trial in 242 evaluable patients with T1-3a, N0-1, and M0 breast cancer was initiated 4 years ago. The well-tolerated, oral combination chemotherapy with six cycles of Leukeran plus methotrexate plus fluorouracil (LMF) plus repeated BCG skin scarifications was used. After 4 years, the following results were seen: (1) significant increase of relapse-free (RFS) and also overall survival (S) in both pre- and postmenopausal node-negative patients versus surgical controls (RFS 91.1 vs. 701%, P = 0.003; S 96 vs. 88%, P = 0.03); (2) no significant increase of RFS or S in pre- and postmenopausal node-positive patients versus surgical controls (RFS 50.1 versus 44%, P = 0.49; S 70 versus 68 %, P = 0.9, respectively); (3) Patients receiving greater than 90% of the planned LMF dose showed significantly better survival after 4 years; and (4) Nonrandomized comparison with concurrent Swiss adjuvant studies with LMF alone indicate no beneficial or harmful effect of BCG skin scarifications in addition to the six-cycle LMF.

Whole globe enucleation versus in situ corneal excision: a study of tissue trauma and contamination.

Twenty-four pair of eyes donated to the Minnesota Lions Eye Bank were studied to determine the effect of corneal procurement methods on tissue quality. Eyes studied were ineligible for transplantation because of a preexisting medical condition other than sepsis or age of > 75 years. The procurement technique was randomized for each donor. One cornea was procured in situ (IS), whereas the fellow eye was enucleated and processed in the laboratory (EN). Procurement protocols were standard Eye Bank Association of America methods. Tissue characteristics were scored according to standard eye bank protocols. Cultures were performed at the time of tissue procurement and following storage for 7 days in Dexol media. With the exception of endothelial striae, no statistical difference was found between groups for any tissue characteristics. The average score for endothelial striae in the IS group was greater than twice that of the EN group. Initial cultures were positive in 10 of 24 in the IS group and four of 24 in the EN group. Each group had three positive end-storage cultures. These results demonstrate superior tissue decontamination after initial processing and less endothelial cell trauma with standard enucleation when compared to in situ corneal excisions.

The influence of staining procedure on differential round cell analysis in stained smears of human semen.

Giemsa and Bryan-Leishman smear staining techniques have been quantitatively evaluated for their ability to determine round cells in human semen. Samples of fertile and vasectomy ejaculates were compared against counts obtained from semithin Araldite sections stained with toluidine blue. TEM studies and immunogold staining of the Pradite section permitted identification and quantitation of nucleated cell profiles. Differential counts from each of the three stains on the same set of semen samples were compared using regression analysis. Counts of seminiferous tubule elements from stain to stain correlated well (r > 0.9). Numerical analyses indicated, however, that leucocytes were commonly misidentified. The r values for neutrophils were less than 0.8 and as low as 0.55 for lymphocytes. These low correlations presumably were due to failures to distinguish between these cells and seminiferous tubule elements.

[A view of general practice]. / Das Bild der Allgemeinpraxis.

What happens during our consultation and what are the determining factors or specific practice patterns in general practice? Six Swiss general practitioners discuss this questions based on a random sample of 300 descriptions of unbiased consultations. Further information obtained from the patient after the consultation by questionnaire and a recorded semi-structured interview was analysed. In the following article the methods are presented.

[Significance of diagnostic aspects in general practice]. / Uber die Bedeutung von diagnostischen Aspekten in der Allgemeinpraxis.

The role of the 'diagnosis' in general practice is different from that in teaching hospitals, but a broader definition is needed. In general practice the spectrum of diagnoses appears to be almost unlimited ('for every patient his own diagnosis'). Therefore, the author calls in question any classification system. In a personal study of 300 consultations in the offices of six Swiss general practitioners, no main diagnosis was reported in 16%, and in one third the main diagnosis was uncertain. The impact of the diagnosis on the therapeutic consequences or on prognosis seems to be overestimated. Of the stated diagnoses most were somatic, but not in the sense of 'clinical' entities. Only few patients are interested in our diagnostic terms. Significant inter-practitioner variations in the diagnostic approach are discussed.

[Is there a typical general practitioner?]. / Gibt es den typischen Allgemeinpraktiker?

A random sample of 300 unbiased consultations on the premises of six Swiss general practitioners was analysed. In this article the results of the 'hard facts' (from patient questionnaires and the physicians tape-recorded consultation's essentials) are referred. The consultation length (average 16.5 min.) was underestimated by doctor and patient in 64% and 41% respectively. 81% of the patients saw us as their 'family doctor'. This term, however, is badly defined. Previous visits at home had taken place in 26 to 54% of all cases. Full patient satisfaction with the consultation was found in 80 to 90%, and the patients attested an optimal emotional approach. Also the financial aspects are mentioned. The authors are impressed by the finding of significant inter-doctor differences of important physician's practice patterns.