Synthesis and characterization of new water stable antimony(III) complex with pyrimidine-2-thione and in vitro biological study

A novel water stable, antimony(III) complex with the heterocyclic thioamide; 2-mercapto-pyrimidine (pmtH), of formula [Sb(pmt)₃] · 0.5(CH₃OH), has been synthesized and characterized by elemental analysis, ¹H, ¹³C NMR and FT-IR spectroscopic techniques. Crystal structure of the molecule has been determined by X-ray diffraction at ambient conditions. The compound [C₁₂H₉N₆S₃Sb · 0.5(CH₃OH)] is monoclinic, space group P2₁/c, a = 7.0646(7), b = 16.3767(14), c = 14.7265(13) Å, β = 92.016(7)°, Z = 4. In complex, three sulfur and three nitrogen atoms from thione ligands form a distorted pendagonal pyramidal geometry around antimony(III). The toxicity of the compound against tumor pleiomorphic cells, which has been isolated from a leiomyosarcoma tumor in the Wistar rat (chemical carcinogenesis using BaP) was studied in vitro. The results show that the compound did not destroy or prevent multiplication in vitro in leiomyosarcoma cells in low doses. The influence of the compound in the platelet aggregation, which correlates with the above tumor cells enhanced metastatic potential, has also been studied. The anti-metastatic capability study shows that the compound inhibited cancer cell induced aggregation up to the value of 10% in all mM concentrations tested.     

Separating Bedtime Rest from Activity Using Waist or Wrist-Worn Accelerometers in Youth

Recent interest in sedentary behavior and technological advances expanded use of watch-size accelerometers for continuous monitoring of physical activity (PA) over extended periods (e.g., 24 h/day for 1 week) in studies conducted in natural living environment. This approach necessitates the development of new methods separating bedtime rest and activity periods from the accelerometer recordings. The goal of this study was to develop a decision tree with acceptable accuracy for separating bedtime rest from activity in youth using accelerometer placed on waist or wrist. Minute-by-minute accelerometry data were collected from 81 youth (10–18 years old, 47 females) during a monitored 24-h stay in a whole-room indirect calorimeter equipped with a force platform covering the floor to detect movement. Receiver Operating Characteristic (ROC) curve analysis was used to determine the accelerometer cut points for rest and activity. To examine the classification differences, the accelerometer bedtime rest and activity classified by the algorithm in the development group (n = 41) were compared with actual bedtime rest and activity classification obtained from the room calorimeter-measured metabolic rate and movement data. The selected optimal bedtime rest cut points were 20 and 250 counts/min for the waist- and the wrist-worn accelerometer, respectively. The selected optimal activity cut points were 500 and 3,000 counts/min for waist and wrist-worn accelerometers, respectively. Bedtime rest and activity were correctly classified by the algorithm in the validation group (n = 40) by both waist- (sensitivity: 0.983, specificity: 0.946, area under ROC curve: 0. 872) and wrist-worn (0.999, 0.980 and 0.943) accelerometers. The decision tree classified bedtime rest correctly with higher accuracy than commonly used automated algorithm for both waist- and wrist-warn accelerometer (all p<0.001). We concluded that cut points developed and validated for waist- and wrist-worn uniaxial accelerometer have a good power for accurate separation of time spent in bedtime rest from activity in youth.     

Hyperthermia effect on lipolytic processes in rat blood and adipose tissue

Rats anaesthetized with Brevinarcon were placed in a high-temperature chamber (air temperature 50 degrees C, relative humidity 50%) for induction of hyperthermia (rectal temperature 41.0 +/- +/- 0.5 degrees C). The control group comprised rats anaesthetized in the same way but kept at room temperature. In the serum in both groups glucose, free fatty acids, immunoreactive insulin, lipolytic activity and ability to mobilize lipids in vitro were determined. It was shown that the glucose and free fatty acid levels and the activity mobilizing serum lipids in vitro in the rats subjected to hyperthermia were lower than in the control group by 12%, 23% and 150% respectively. The lipolytic activity of the serum of rats subjected to hyperthermia was 42% higher, and the level of immunoreactive insulin rose by about 224% in relation to the control group. These results point to inhibition of lipolysis in the adipose tissue with simultaneous activation of intravascular lipolysis during hyperthermia in rats.     

Synthesis,Structural Characterization and Antimicrobial Evaluation of Ruthenium Complexes with Heteroaromatic Carboxylic Acids

The antibacterial and antibiofilm activities of two new ruthenium complexes against E. coli, S. aureus, P. aeruginosa PAO1 (laboratory strain) and P. aeruginosa LES B58 (clinical strain) were evaluated. Complexes, mer‐[Ru^III(2‐bimc)₃] ? H₂O ( 1 ) and cis‐[Ru^IVCl₂(2,3‐pydcH)₂] ? 4H₂O ( 2 ), were obtained using aromatic carboxylic acid ligands, namely, 1H‐benzimidazole‐2‐carboxylic acid (2‐bimcH) and pyridine‐2,3‐dicarboxylic acid (2,3‐pydcH₂). Compounds were physicochemically characterized using X‐ray diffraction, Hirshfeld surface analysis, IR and UV/VIS spectroscopies, as well as magnetic and electrochemical measurements. Structural characterization revealed that Ru(III) and Ru(IV) ions in the complexes adopt a distorted octahedral geometry. The intermolecular classical and weak hydrogen bonds, and π???π contacts significantly contribute to structure stabilization, leading to the formation of a supramolecular assembly. Biological studies have shown that the Ru complexes inhibit the growth of bacteria and biofilm formation by the tested strains and the complexes seem to be a potential as antimicrobial agents.     

Assessment of the influence of viscoelasticity of cornea in animal ex vivo model using air‐puff optical coherence tomography and corneal hysteresis

Application of the air‐puff swept source optical coherence tomography (SS‐OCT) instrument to determine the influence of viscoelasticity on the relation between overall the air‐puff force and corneal apex displacement of porcine corneas ex vivo is demonstrated. Simultaneous recording of time‐evolution of the tissue displacement and air pulse stimulus allows obtaining valuable information related in part to the mechanical properties of the cornea. A novel approach based on quantitative analysis of the corneal hysteresis of OCT data is presented. The corneal response to the air pulse is assessed for different well‐controlled intraocular pressure (IOP) levels and for the progression of cross‐linking‐induced stiffness of the cornea. Micrometer resolution, fast acquisition and noncontact character of the air‐puff SS‐OCT measurements have potential to improve the in vivo assessment of mechanical properties of the human corneas.      

Current and future potential distributions of three Dracaena Vand. ex L. species under two contrasting climate change scenarios in Africa

Forest undergrowth plants are tightly connected with the shady and humid conditions that occur under the canopy of tropical forests. However, projected climatic changes, such as decreasing precipitation and increasing temperature, negatively affect understory environments by promoting light‐demanding and drought‐tolerant species. Therefore, we aimed to quantify the influence of climate change on the spatial distribution of three selected forest undergrowth plants, Dracaena Vand. ex L. species, D. afromontana Mildbr., D. camerooniana Baker, and D. surculosa Lindl., simultaneously creating the most comprehensive location database for these species to date. A total of 1,223 herbarium records originating from tropical Africa and derived from 93 herbarium collections worldwide have been gathered, validated, and entered into a database. Species‐specific Maxent species distribution models (SDMs) based on 11 bioclimatic variables from the WorldClim database were developed for the species. HadGEM2‐ES projections of bioclimatic variables in two contrasting representative concentration pathways (RCPs), RCP2.6 and RCP8.5, were used to quantify the changes in future potential species distribution. D. afromontana is mostly sensitive to temperature in the wettest month, and its potential geographical range is predicted to decrease (up to ?63.7% at RCP8.5). Optimum conditions for D. camerooniana are low diurnal temperature range (6–8°C) and precipitation in the wettest season exceeding 750 mm. The extent of this species will also decrease, but not as drastically as that of D. afromontana. D. surculosa prefers high precipitation in the coldest months. Its potential habitat area is predicted to increase in the future and to expand toward the east. This study developed SDMs and estimated current and future (year 2050) potential distributions of the forest undergrowth Dracaena species. D. afromontana, naturally associated with mountainous plant communities, was the most sensitive to predicted climate warming. In contrast, D. surculosa was predicted to extend its geographical range, regardless of the climate change scenario.     

Effects of glyceryl polyethylene glycol ricinoleate on nutrient utilisation and performance of broiler chickens

A completely randomised design study with a 2 × 2 factorial arrangement was conducted to observe effects of an emulsifier (glyceryl polyethylene glycol ricinoleate (GPR)) on nutrient utilisation and performance of broiler chickens. A total of 384 male broiler chickens were used to determine the influence of GPR (without addition or added at 0.04% of diet) and two levels of apparent metabolisable energy (AME_N) (according to standard requirements (Diets SE) or energy reduced by 0.4 MJ/kg diet (Diets LE)) on birds’ performance and apparent total tract digestibility (ATTD). ATTD of ether extract (EE) and AME_N were measured on d 14 and 35, and ATTD of neutral detergent fibre (NDF) was measured on d 35. All diets were based on wheat–maize–soybean meal with rapeseed oil and lard (blend of 50:50) as fat sources. During the grower period and the whole trial, birds fed Diets supplemented with GPR were characterised by higher body weight gain (BWG) and lower feed conversion ratio (FCR) compared to chicken receiving diets without GPR (p < 0.05). At the end of experiment, birds fed Diet LE without GPR were characterised by lower BWG and higher FCR (p < 0.05). Supplementation with GPR caused a higher ATTD of EE for diets SE and LE at d 14 and 35 (p < 0.05). Moreover, the GPR addition to Diet LE improved ATTD of NDF at d 35 (p < 0.05). In conclusion, the findings suggest that GPR effects the digestion of a blend of animal fat/rapeseed oil positively, even in a practical maize–wheat-based broiler diet with decreased AME_N level.     

High Viral Loads of Epstein-Barr Virus DNA in Peripheral Blood of Patients with Chronic Lymphocytic Leukemia Associated with Unfavorable Prognosis

Epstein-Barr virus (EBV) is a ubiquitous γ-herpesvirus that infects more than 90% of the world population. The potential involvement of EBV in the clinical course of chronic lymphocytic leukemia (CLL) remains unexplained. The aim of this study was to determine whether EBV-DNA load in the peripheral blood mononuclear cells (PBMCs) of CLL patients may influence heterogeneity in the course of the disease. The study included peripheral blood samples from 115 previously untreated patients with CLL (54 women and 61 men) and 40 healthy controls (16 women and 24 men). We analyzed the association between the EBV-DNA load in PBMCs and the stage of the disease, adverse prognostic factors, and clinical outcome. Detectable numbers of EBV-DNA copies in PBMCs were found in 62 out of 115 CLL patients (53.91%). The EBV-DNA copy number/μg DNA was significantly higher in patients who required early implementation of treatment, presented with lymphocyte count doubling time <12 months, displayed CD38-positive or ZAP-70-positive phenotype, and with the del(11q22.3) cytogenetic abnormality. Furthermore, the EBV-DNA copy number/μg DNA showed significant positive correlation with the concentrations of lactate dehydrogenase (LDH) and beta-2-microglobulin. We have shown that in CLL patients, higher EBV-DNA copy number predicted shorter survival and shorter time to disease progression, and it was associated with other established unfavorable prognostic factors. This suggests that EBV may negatively affect the outcome of CLL.