On-DNA Synthesis of Multisubstituted Indoles.

The increasing role of the DNA-encoded library technology in early phase drug discovery represents a significant demand for DNA-compatible synthetic methods for therapeutically relevant heterocycles. Herein, we report the first on-DNA synthesis of multisubstituted indoles via a cascade reaction of Sonogashira coupling and intramolecular ring closure. Further functionalization by Suzuki coupling at the third position exploits a diverse chemical space. The high fidelity of the method also enabled the construction of an indole-based mock library.

Electrophilic MiniFrags Revealed Unprecedented Binding Sites for Covalent HDAC8 Inhibitors.

Screening of ultra-low-molecular weight ligands (MiniFrags) successfully identified viable chemical starting points for a variety of drug targets. Here we report the electrophilic analogues of MiniFrags that allow the mapping of potential binding sites for covalent inhibitors by biochemical screening and mass spectrometry. Small electrophilic heterocycles and their N-quaternized analogues were first characterized in the glutathione assay to analyze their electrophilic reactivity. Next, the library was used for systematic mapping of potential covalent binding sites available in human histone deacetylase 8 (HDAC8). The covalent labeling of HDAC8 cysteines has been proven by tandem mass spectrometry measurements, and the observations were explained by mutating HDAC8 cysteines. As a result, screening of electrophilic MiniFrags identified three potential binding sites suitable for the development of allosteric covalent HDAC8 inhibitors. One of the hit fragments was merged with a known HDAC8 inhibitor fragment using different linkers, and the linker length was optimized to result in a lead-like covalent inhibitor.

Temperature dependence of nitrification in a membrane-aerated biofilm reactor.

The membrane-aerated biofilm reactor (MABR) is a novel method for the biological treatment of wastewaters and has been successfully applied for nitrification. To improve the design and adaptation of MABR processes for colder climates and varying temperatures, the temperature dependence of a counter-diffusional biofilm's nitrification performance was investigated. A lab-scale MABR system with silicone hollow fibre membranes was operated at various temperatures between 8 and 30°C, and batch tests were performed to determine the ammonia oxidation kinetics. Biofilm samples were taken at 8 and 24°C and analysed with 16S rRNA sequencing to monitor changes in the microbial community composition, and a mathematical model was used to study the temperature dependence of mass transfer. A high nitrification rate (3.08 g N m-2 d-1) was achieved at 8°C, and temperature dependence was found to be low (θ = 1.024-1.026) compared to suspended growth processes. Changes in the community composition were moderate, Nitrospira defluvii remaining the most dominant species. Mass transfer limitations were shown to be largely responsible for the observed trends, consistent with other biofilm processes. The results show that the MABR is a promising technology for low temperature nitrification, and appropriate management of the mass transfer resistance can optimise the process for both low and high temperature operation.

A stepwise one-pot synthesis of aliphatic thiols and their derivatives from acrylamides and sulfur.

Elemental sulfur enables the convenient formation of C-S bonds and the direct incoporation of S-S bonds. The reactivity of easily accessible electron deficient alkenes towards sulfur, however, is barely disclosed. Herein, we investigated the reactivity of acrylamides with sulfur and eventually developed a new pseudo-multicomponent reaction for the preparation of polysulfides. Sequential one-pot reduction led to diversely substituted thiols. Additional third stage one-pot modifications provided thioethers, unsymmetric disulfide and thioester.

Continuous-Flow Synthesis of Thioureas, Enabled by Aqueous Polysulfide Solution.

We have developed the continuous-flow synthesis of thioureas in a multicomponent reaction starting from isocyanides, amidines, or amines and sulfur. The aqueous polysulfide solution enabled the application of sulfur under homogeneous and mild conditions. The crystallized products were isolated by simple filtration after the removal of the co-solvent, and the sulfur retained in the mother liquid. Presenting a wide range of thioureas synthesized by this procedure confirms the utility of the convenient continuous-flow application of sulfur.

Chromatography-Free Multicomponent Synthesis of Thioureas Enabled by Aqueous Solution of Elemental Sulfur.

The development of a new three-component chromatography-free reaction of isocyanides, amines and elemental sulfur allowed us the straightforward synthesis of thioureas in water. Considering a large pool of organic and inorganic bases, we first optimized the preparation of aqueous polysulfide solution from elemental sulfur. Using polysulfide solution, we were able to omit the otherwise mandatory chromatography, and to isolate the crystalline products directly from the reaction mixture by a simple filtration, retaining the sulfur in the solution phase. A wide range of thioureas synthesized in this way confirmed the reasonable substrate and functional group tolerance of our protocol.

A novel three-component reaction between isocyanides, alcohols or thiols and elemental sulfur: a mild, catalyst-free approach towards O-thiocarbamates and dithiocarbamates.

A new multicomponent reaction has been developed between isocyanides, sulfur and alcohols or thiols under mild reaction conditions to afford O-thiocarbamates and dithiocarbamates in moderate to good yields. The one-pot reaction cascade involves the formation of an isothiocyanate intermediate, thus a catalyst-free synthesis of isothiocyanates, as valuable building blocks from isocyanides and sulfur is proposed, as well. The synthetic procedure suits the demand of a modern organic chemist, as it tolerates a wide range of functional groups, it is atom economic and easily scalable.

Evaluation of the Effect of Hévíz Mud in Patients with Hand Osteoarthritis: A Randomized, Controlled, Single-Blind Follow-Up Study.

BACKGROUND: Heat therapy is one of the most popular non-pharmacological treatments for osteoarthritis of the hand. OBJECTIVES: To investigate the therapeutic and chemical effects of Hévíz mud on patients with hand osteoarthritis. METHODS: We randomly assigned 47 patients with mild-to-moderate hand osteoarthritis to two groups. Patients in group 1 (n=23) received Hévíz mud applied directly to both hands, whereas patients in group 2 (n=24) also received mud to both hands, but nylon gloves separated the skin from the mud. Patients in both groups underwent five 20 minute treatment sessions per week for 3 weeks. The temperature of the mud was 42°C. Outcome measures were Visual Analogue Scale (VAS) scores, hand grip strength, the number of swollen and tender joints of the hand, the duration of morning joint stiffness, Health Assessment Questionnaire score, and EuroQoL Group 5-Dimension Self-Report Questionnaire score. The study parameters were evaluated at baseline, immediately after treatment, and after 16 weeks. RESULTS: Both groups showed improvement in nearly all assessed parameters at the end of treatment and at 16 weeks from the start of treatment. At the week 16 follow-up visit, the patient group directly treated with mud showed significantly better improvement in VAS for II and IV parameters and in swollen joint count in both hands compared to the nylon glove-mud group. CONCLUSIONS: Hévíz mud therapy significantly improved objective and subjective parameters in patients with hand osteoarthritis and had a beneficial effect on the patients' quality of life. Further studies are required to evaluate the chemical effects of the mud.

Evaluation of the effect of balneotherapy in patients with osteoarthritis of the hands: a randomized controlled single-blind follow-up study.

OBJECTIVE: To evaluate the effectiveness of thermal mineral water compared with magnetotherapy without balneotherapy as control, in the treatment of hand osteoarthritis. DESIGN: Randomized controlled single-blind follow-up study. SETTING: Rheumatology specialist clinic of Gunaras Health Spa. SUBJECTS: Patients between 50 and 70 years of age with hand osteoarthritis, randomly assigned into three groups. INTERVENTIONS: The subjects in the first two groups bathed in thermal mineral water of two different temperatures (36°C and 38°C) for three weeks five times a week for 20 minutes a day and received magnetotherapy to their hands three times weekly. The third group received only magnetotherapy. OUTCOME MEASURES: Visual analogue scale scores, handgrip strength, pinchgrip strength, the number of swollen and tender joints of the hand, the duration of morning joint stiffness, Health Assessment Questionnaire, and Short Form-36 questionnaire. The study parameters were administered at baseline, immediately after treatment and after 13 weeks. RESULTS: The study included 63 patients. Statistically significant improvement was observed in several studied parameters after the treatment and during the follow-up study in the thermal water groups versus the control group. The 38°C thermal water treatment significantly improved the pinch strength of the right hand (0.6 (95% confidence interval (CI) 0.2 to 1.1) vs. 0.03 (95% CI -0.3 to 0.4), P < 0.05) and the Health Assessment Questionnaire parameters (-0.4 (95% CI -0.6 to -0.2) vs. -0.1 (95% CI -0.2 to 0.1), P < 0.01) even in the long term. CONCLUSIONS: Balneotherapy combined with magnetotherapy improved the pain and function as well as the quality of life in patients with hand osteoarthritis.

The effect of spa therapy in chronic low back pain: a randomized controlled, single-blind, follow-up study.

Effect of thermal water with high mineral content on clinical parameters and quality of life of patients with chronic low back pain was studied. In this randomized controlled, single-blind, follow-up study, 60 patients with chronic low back pain were randomized into two groups. The treatment group received balneotherapy with thermal-mineral water, and the control group bathed in tap water. Changes of the followings were evaluated: visual analogue scale (VAS) for pain, range of motion for the lumbar spine, Oswestry index, EuroQol-5D and Short Form-36 questionnaires. In the treatment group, the mobility of the lumbar spine, the Oswestry index, the VAS scores and the EuroQoL-5D index improved significantly. SF-36 items improved significantly in the treated group compared with baseline except for two parameters. Our study demonstrated the beneficial effect of balneotherapy with thermal mineral versus tap water on clinical parameters, along with improvements in quality of life.

Diuretic treatment affects the length of torpor bouts in hibernating European ground squirrels (Spermophilus citellus).

During the hibernation season, hibernating mammals show a sequence of torpor bouts that are interrupted by periodic arousals and brief normothermic periods. The functional significance of periodic arousals is still uncertain. We hypothesized that the imbalances in water economy may play a role in the timing of periodic arousals in hibernating species. We applied furosemide, a diuretic drug, to assess whether hibernating European ground squirrels respond to elevated urine production by shortening their torpor bouts. Urine production in the treated squirrels increased and led to more frequent arousals, presumably to restore water balance by recovery of lost water from blood and tissues. The length of the subsequent normothermic phase was not affected by the diuretic treatment. Body mass change correlated primarily with the amount of voided urine. Although our study did not identify the underlying mechanism, our results support the view that water economy, and water loss may play a role in the timing of periodic arousals.

Effect of thermal water and adjunctive electrotherapy on chronic low back pain: a double-blind, randomized, follow-up study.

OBJECTIVE: The aim of this study was to evaluate the effectiveness of thermal mineral water, compared with tap water in the treatment of low back pain. METHODS: This randomized, double-blind, controlled, follow-up study included 71 patients who underwent 20-minute daily treatment sessions with medicinal water or with tap water, both at a temperature of 34 degrees C, on 21 occasions. Both groups underwent additional adjunctive electrotherapy. Outcome measures were visual analogue scale scores, Schober's sign, Domján's signs, Oswestry disability and Short Form-36 questionnaire. The study parameters were administered at baseline, immediately after treatment, and after 15 weeks. RESULTS: After treatment, there was a significant improvement in all parameters in the thermal water group. This improvement was still evident after 15 weeks. The improvement in the control group was less substantial compared with baseline values. Comparison of the 2 treatments revealed a statistically significant difference in 3 outcome parameters (visual analogue scale scores III, IV and Schober's index). In the subset of patients who completed the study according to the protocol, the greater efficacy of treatment with thermal water was also confirmed by the other study parameters. CONCLUSION: In the group treated with thermal water, improvement occurred earlier, lasted longer and was statistically significant.

Quantitative spin trapping and triplet quenching by radicals for in vivo studies. I. The chemical model.

In order to determine quantitatively the free radical content and its changes affected by additives using spin trapping under in vivo conditions, an approach is suggested carrying out experiments in a completely mixed open system (CMOS). Measurements have been carried out for a chemical oxidation process as a model system, and analysis of products and of the spin trap was extended by kinetic ESR spectrometry of the spin adducts. Since in a CMOS differential equations of accumulation of all species can be transformed into algebraic expressions using available rate constants for the formation of the spin adducts, corresponding concentrations of free radicals have been calculated. In addition, it has been established that triplet excited photosensitizers have a double effect: increasing the rate of initiation by decomposing hydroperoxide-type compounds and inhibiting the overall process by interactions with free radicals. Results indicate that by changing the "reaction vessel" the method can be applied for ex vivo and in vivo systems.

MECHGEN: computer aided generation and reduction of reaction mechanisms.

The paper describes selection rules implemented in a software generating "possible reaction mechanism", i.e. a set of elementary reactions chosen from all stoichiometrically possible reactions. The novelty of the approach lies in the fact that the user has to define all species involved (reactants, intermediates, products), and the rules applied with user-set limits reduce the resulting mechanism to a reasonable set of possible elementary reactions. The computer code consists of five parts: (i) definition of species, and introducing its characteristics (structure and thermodynamic data); (ii) definition of the reacting system and generation of all stoichiometrically possible reactions; (iii) reduction of the mechanisms using complexity and thermodynamic constraints based on user-set limits; (iv) calculation of the resulting pathways (routes of the various atoms or groups of atoms transferred from one species to another); and (v) tools to help visualization of the process by finding those elementary processes which realize a given pathway. Reasonable flexibility is ensured for using selection rules based on various criteria with limits set by the user. The various pathways are shown (in a matrix form), which offers an overview of the entire process.