A series of new paramagnetic six-coordinate gallium complexes based on 3,6-di-
tert
-butyl-
o
-benzoquinone with N-donor ligands, such as pyridine (Py), 2,2′-dipyridyl (2,2′-dipy), and 4,4′-di-
tert
...-butyl-2,2′-dipyridyl (Bu
t
-dipy), were synthesized and structurally characterized. The molecular structures of the synthesized compounds were established by single-crystal X-ray diffraction. The complexes with bidentate N-donor ligands have the
cis
arrangement of the
o
-quinone ligands, whereas the compound with coordinated pyridine molecules has the
trans
arrangement of the diolate moieties. The synthesized compounds are characterized by spin density delocalization between the differently charged redox-active ligands. Regardless of the metal coordination environment, the near-IR region of the electronic absorption spectra of all the synthesized complexes show a low-intensity charge-transfer band between the catecholate and
o
-semiquinolate ligands, which was confirmed by DFT calculations.
A method for the preparation of 2-morpholinocinchomeronic acid dinitrile derivatives (2-morpholinopyridine-3,4-dicarbonitriles) was developed. The optical properties of the obtained products were ...investigated both in solution and the solid state. It was found that the synthesized compounds exhibit fluorescence both in solution and in the solid state from the blue to green region of the spectrum, depending on the substituents at the fifth and sixth positions of the pyridine ring. It was found that the relative quantum yield in benzene reaches 50%.
•The influence of a soluble fullerene C60 derivative (F-828) on HELFs was studied.•At <0.1μM F-828 promotes cell processes of proliferation and reparation.•Between 5 and 25μM F-828 induces ROS ...generation and DNA breaks in nuclei.•F-828 concentrations higher than 25μM are toxic for HELFs.•F-828 can potentially induce fibrosis in the pulmonary tissue.
Water-soluble fullerenes have been studied as potential nanovectors and therapeutic agents, but their possible toxicity is of concern. We have studied the effects of F-828, a soluble fullerene C60 derivative, on diploid human embryonic lung fibroblasts (HELFs) in vitro. F-828 causes complex time-dependent changes in ROS levels. Inhibition of Nox4 activity by plumbagin blocks F-828-dependent ROS elevation. F-828 induces DNA breaks, as measured by the comet assay and γH2AX expression, and the activities of the transcription factors NF-kB and p53 increase. F-828 concentrations>25μM are cytotoxic; cell death occurs by necrosis. Expression levels of TGF-β, RHOA, RHOC, ROCK1, and SMAD2 increase following exposure to F-828. Our results raise the possibility that fullerene F-828 may induce pulmonary fibrosis in vivo.
4-Amino-6-aryl-2-sulfanylpyridine-3,5-dicarbonitriles were obtained in two ways: by nucleophilic substitution of the halogen atom in 2-halopyridines under the action of thiols and by alkylation of ...pyridine-2-thiones with alkyl halides.
The reaction of 4-amino-6-aryl-2-halopyridine-3,5-dicarbonitriles with thioglycolic acid ethyl ester was used to synthesize a series of new efficient fluorophores of thieno2,3-
b
pyridine series. The ...long-wavelength absorption bands of DMSO solutions of the prepared compounds are at the boundary of the UV and visible regions of the spectrum (λ
abs
375–388 nm) and show an ambiguous influence of the substituent electronic effect, that was explained by quantum chemical calculations. The emission maxima are in the yellow-green region (λ
em
490– 510 nm) and they are blue-shifted in the presence of electron donor groups with slightly increasing intensity (Φ
em
37.8–60.6%). It was found that the nitro group presence causes a complete photoluminescence quenching both in solution and in the solid state. In addition, the position of the emission maximum (λ
em
473–505 nm) and its intensity (Φ
em
3.6–72.7%) strongly depend on the polarity and the basic properties of the medium, that was established using the Catalan empirical model.
The reaction of 2-chloropyridine-3,4-dicarbonitrile with anilines in propan-2-ol in the presence of
N
,
N
- diisopropylethylamine (DIPEA) in a sealed vial at 120°С involves the nucleophilic ...substitution of chlorine and yields 2-(arylamino)pyridin-3,4-dicarbonitriles.
Improved Extruded Thermoelectric Materials Lavrentev, M. G.; Drabkin, I. A.; Ershova, L. B. ...
Journal of electronic materials,
05/2020, Letnik:
49, Številka:
5
Journal Article
Recenzirano
Using improved extrusion technology for bismuth antimony tellurides, RMT has developed new extruded thermoelectric materials (TEM) with increased thermoelectric figure of merit (
Z
). The
p
-type ...materials exhibit maximum
Z
values of 3.28 × 10
−3
K
−1
to 3.32 × 10
−3
K
−1
in the electrical conductivity range from 900 Ω
−1
cm
−1
to 1100 Ω
−1
cm
−1
. The corresponding
Z
values for the
n
-type materials lie in the similar range of 2.82 × 10
−3
K
−1
to 2.87 × 10
−3
K
−1
. The wide variation of the electrical conductivity allows their application in miniature thermoelectric coolers (TEC) for cooling and temperature stabilization in the temperature range from 225 K to 350 K. Using the improved TEM, miniature TECs with pellet height of 0.3 mm were manufactured and tested; the test results showed that the maximum temperature difference was 2 K to 3 K higher while the energy consumption was 10% to 15% lower than for standard RMT miniature TEC.
New one-dimensional metal−organic frameworks of magnesium Mg(pQ)·2DMF
n
(
I
), Mg(pQ)·2DMAA
n
(
II
), and Mg(pQ)·2(NMP)
n
(
III
) (pQ is the 2,5-dihydroxy-3,6-di-
tert
-butyl-
para
-benzoquinone ...dianion) are synthesized by the solvothermal method in different solvents (
N
,
N
-dimethylformamide (DMF),
N
,
N
-dimethylacetamide (DMAA), and
N
-methyl-2-pyrrolidone (NMP)). The crystal structures of compounds
I
and
III
are determined by X-ray structure analysis (CIF files CCDC nos. 2058147 (
I
) and 2058148 (
II
)). The spectral characteristics and thermal stability of the synthesized metal−organic frameworks are studied.
Aim
. To characterize patients accessing lipid clinic and assess the efficiency of treatment in a specialized medical center.
Material and methods
. A retrospective analysis of the surviving medical ...records of outpatients who visited the lipid clinic of the National Research Center for Therapy and Preventive Medicine (Moscow, Russia) in 2011-2019 (n=675) was carried out. Cardiovascular risk (CVR) and target lipoproteins levels were evaluated in accordance with actual guidelines for the diagnostics and correction of dyslipidemias.
Results
. The mediana of lipid clinic patients age was 57 46;65 years. Female persons attend lipid clinic more often (61.5%). 48.5% of patients had low density lipoprotein cholesterol (LDL-c) >4.9 mmol/L, 7.7% had triglycerides level >5.5 mmol/L. Most of the patients were diagnosed with type IIa hyperlipidemia (44,1%) or type IIb (28,0%). Inherited impaired lipid metabolism was diagnosed in 27.7% individuals. 12.7% of the patients had familial hypercholesterolemia, 57.4% – had secondary causes of impaired lipid metabolism. More than half of the patients (52.4%) had low or moderate CVR, 28.1% had a very high CVR. High or very high CVR individuals revisited the lipid clinic more often than people with lower risk (68.2% vs. 35.4%). Revisiting patients (25.4%) reached LDL-c targets more often (33.3% of very high CVR patients; 45.5% of moderate-risk people) than in ordinary outpatient practice. High-intensity statin therapy was recommended for 32% of patients, and combined lipid-lowering therapy – for 14.8%. Among very high CVR individuals, combined lipid-lowering therapy was prescribed for 38.5%. Given the lipid-lowering therapy prescribed in the lipid clinic, LDL-с<1.8 mmol/L and<1.5 mmol/L will be achieved at 40.7% and 32.9% of patients with very high СVR.
Conclusion
. Lipid clinic is an important part of the medical care system for long-term follow-up of patients with impaired lipid metabolism, and it is more efficient in achieving target values of lipids and correcting risk factors in comparison with the primary medical service.
PDF