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The emission of Er 3+ provides three combinations of emission bands suitable for ratiometric luminescence thermometry. Two combinations utilize ratios of visible emissions ( 2 H 11/2 → 4 I 15/2 at 523 nm/ 4 S 3/2 → 4 I 15/2 at 542 nm and 4 F 7/2 → 4 I 15/2 at 485 nm/ 4 S 3/2 → 4 I 15/2 at 545 nm), while emissions from the third combination are located in near-infrared, e.g., in the first biological window ( 2 H 11/2 → 4 I 13/2 at 793 nm/ 4 S 3/2 → 4 I 13/2 at 840 nm). Herein, we aimed to compare thermometric performances of these three different ratiometric readouts on account of their relative sensitivities, resolutions, and repeatability of measurements. For this aim, we prepared Yb 3+ ,Er 3+ :YF 3 nanopowders by oxide fluorination. The structure of the materials was confirmed by X-ray diffraction analysis and particle morphology was evaluated from FE-SEM measurements. Upconversion emission spectra were measured over the 293-473 K range upon excitation by 980 nm radiation. The obtained relative sensitivities on temperature for 523/542, 485/542, and 793/840 emission intensity ratios were 1.06 ± 0.02, 2.03 ± 0.23, and 0.98 ± 0.10%K -1 with temperature resolutions of 0.3, 0.7, and 1.8 K, respectively. The study showed that the higher relative temperature sensitivity does not necessarily lead to the more precise temperature measurement and better resolution, since it may be compromised by a larger uncertainty in measurement of low-intensity emission bands.

Purpose: In the early 1970s, a number of authors described the development of Balkan endemic nephropathy (BEN) in immigrants in endemic regions. The aim of this study was to examine whether immigrants in endemic regions are suffering from BEN today., Methods: The study involved 193 residents of two endemic regions divided into three groups: two groups of native residents-(1) members of BEN families, (2) members of non-BEN families, and (3) immigrants, who had moved from non-affected settlements to the endemic regions of Kolubara (38 years ago) or Semberia (20 years ago). All persons were subjected to an interview, objective examination, kidney ultrasound, and laboratory analysis to detect the presence of BEN consensus diagnostic criteria., Results: The number of immigrants with BEN biomarkers outside cutoff values was significantly lower than for BEN family members. Five BEN family members met diagnostic criteria for BEN and four for suspected BEN. Although five non-BEN family members had different combinations of BEN biomarkers, all of them had diseases other than BEN in which these biomarkers also occurred. None of the immigrants met the criteria for BEN. Nevertheless, one descendant of an immigrant, a 78-year-old male, whose mother was from a non-BEN family in the Kolubara district, exhibited all the criteria for BEN: alpha1-microglobulinuria, chronic renal failure, and anemia., Conclusion: While 30 years ago, BEN was reported equally among immigrants and natives, currently it is diagnosed in some BEN family members in the eighth decade of life, but extremely rarely in immigrants also in old age.

We present an efficient, simple, metal- and solvent-free silica-gel-promoted synthesis of functionalized conjugated dienes by sequential aza-Michael/Michael reactions by starting from commercially available primary amines and propiolic esters. The scope and usefulness of the method is demonstrated for 31 examples, including a range of propiolic esters, aliphatic amines, and differently substituted aromatic amines. For aliphatic amines, the products were obtained within 0.5 to 4 h in 52 to 85 % yield, compared with 3.5 to 22 h under classical solution-phase synthesis, which proceeds with similar or lower yields. The method was found to be particularly useful for weakly nucleophilic aromatic amines, which provided products in 21 to 73 % yield over 2.5 to 9.5 h compared with yields of 0 to 49 % over 1 to 6 d under standard solution-phase conditions, and for more hydrophobic esters that gave products in yields of 47 to 79 % over 1 to 3 h compared with 0 to 45 % over 4 to 114 h in solvent., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The well-known gauche preference in FCCX systems, where X is an electronegative element from Period 2, is widely exploited in synthetic, medicinal, and material chemistry. It is rationalized on the basis of σ(C-H) → σ*(C-F) hyperconjugation and electrostatic interactions. The recent report (Thiehoff, C.; et al. Chem. Sci. 2015, 6, 3565) showed that the fluorine gauche effect can extend to Period 3 elements, such as sulfur. The aim of the present work is to disclose factors governing conformational behavior of FCCS containing systems. We examine conformational preferences in seven classes of compounds by ab initio and DFT calculations and rationalize the results by quantitatively decomposing the anti/gauche isomerization energy into contributions from electrostatic, orbital, dispersion, and Pauli interactions, and energy spent on structural changes. The results show that the fluorine/sulfur gauche effect is primarily electrostatic (63-75%), while all orbital interactions contribute 22-41% to stabilizing interactions. Stereoelectronic effects, involved in orbital interactions, also play a role in gauche conformer stabilization.

Background/aim: A cost-effectiveness analyses of immunomodulatory treatments for relapsing-remitting multiple sclerosis (RRMS) in developed countries have shown that any benefit from these drugs is achieved at very high cost. The aim of our study was to compare the cost-effectiveness of five treatment strategies in patients diagnosed with RRMS (symptom management alone and in combination with subcutaneous glatiramer acetate, intramuscular interferon beta-1a, subcutaneous interferon beta-1a, or intramuscular interferon [beta-1b) in a Balkan country in socio-economic transition., Methods: The Markov model was developed based on the literature about effectiveness and on local Serbian cost calculations. The duration of a cycle in the model was set to a month. The baseline time horizon was 480 months (40 years). The societal perspective was used for costs and outcomes, and they were discounted for 3% annually. Monte Carlo micro simulation with 1000 virtual patients was done., Results: Significant gain with immunomodulatory therapy was achieved only in relapse-free years, while the time spent in health states EDSS 0.0-5.5 was longer with symptomatic therapy only, and gains in life years and QALYs were only marginal. One QALY gained costs more than a billion of Serbian dinars (more than 20 million US dollars), making each of the four immunomodulatory therapies cost-ineffective., Conclusion: Our study suggests that immunomodulatory therapy of RRMS in a Balkan country in socioeconomic transition is not cost-effective, regardless of the type of the therapy. Moderate gain in relapse-free years does not translate to gain in QALYs, probably due to adverse effects of immunomodulatory therapy.

Objectives: In order to study the possible role of nitric oxide (NO) in the development of periodontitis, we measured the concentration of its stable metabolite nitrite (NO2-) in the saliva of patients with periodontitis and healthy subjects., Materials and Methods: We have analysed salivary NO2- concentrations in 25 subjects with rapidly progressive periodontitis (RPP), 25 with adult periodontitis (AP) and in 25 periodontally-healthy persons. The concentrations of NO2- were determined by the Griess reaction in microtitration plates. Periodontal tissue destruction was determined by measuring the attachment level loss using standard methods., Results: Subjects with periodontitis had significantly less NO2- in saliva than healthy subjects. Subjects with RPP had lower NO2- concentrations than those with AP Parotid gland saliva contained less NO2- than sublingual gland or total saliva., Conclusions: Local NO production is decreased in patients with periodontitis. This effect is more pronounced in those with severe types of disease.

Epidemy of enterocolitis at Dimitrovgrad started on the 15th of August 1989, and lasted for a whole month. 2018 persons became ill. Bacteriological cholera tests were performed on 3054 samples of stools from 2558 patients, and of those who were in contact with the sick populations. Stool samples were cultured on the alcal peptonic water, alcal agar, and TCBS agar for vibrio isolation. Suspicious colonies identification was made by biochemical and serological tests. Difference between cholera biotype and eltor was found by differential testings. In 16 examined persons Vibrio colerae biotip eltor serotype Ogara was isolated. Sensitivity to antibiotics was determined by standard disc method.

A single dose of the dopamine agonists L-dopa, bromocriptine or apomorphine produced a protective effect by significantly shortening of the length of stomach ulcerations. A single dose of the dopamine antagonists haloperidol, sulpiride or domperidone potentiated the ulcerogenic effect by extending the length of stomach ulcerations. These results point to the fact that dopamine is involved in the rise and development of experimental stomach ulcers.