Staphylococcus aureus is an extremely infectious and malignant pathogen among many bacteria species. The aim of this work is to provide a robust classification model that would be able to identify S. ...aureus independent of the culture growth stage and the variations in bacteria concentration in suspension and also one that would be able to identify the pathogen among both taxonomically close species of the same genus and taxonomically distant species of different genera, using Fourier transform infrared spectroscopy (FTIR). In total, the spectra of 141 isolates of 17 bacteria have been used. Based on a combination of principal component analysis (PCA) and linear discriminant analysis (LDA), an identification model providing 100% sensitivity and 98% specificity was built. Inherent reliability and flexibility of the model have been shown. The proposed method of analysis allows us to get closer to the diagnostic requirements in the field of clinical microbiology, and it can be utilized for typing of other pathogenic bacteria species.
Lake Vostok is the deepest lake of Antarctica but has poor accessibility for study due to a thick glacial cover, however, water samples of this lake have become available for study just recently. ...Previously, only the microbiome of the ice cover samples was characterized. Here we report results of bacteriological seeding with subsequent identification of the heterotrophic microorganisms (bacteria and micellar fungi) present by 16S rDNA sequencing as well as results of a direct molecular study of the water microbiome. Surprisingly, the data obtained gave evidence of a predominant occurrence of common chemoorganotrophs that were rather psychrotolerant than psychrophilic. We isolated and described strains belonging to eight heterotrophic microbial species able to grow in a rich medium: six bacterial strains belonging to the species
and
,
,
,
sp. and
; and two fungal strains belonging to
sp. and
. Direct study of 16S rDNA purified water samples confirmed the predominance of the
,
, and
(
)
.
A simple one-step approach for the selective synthesis of
exo
-norbornenes with organosilicon substituents is suggested through the direct hydrosilylation of norbornadiene-2,5 with chlorine-free ...silanes. Using the example of norbornadiene-2,5 hydrosilylation with pentamethyldisiloxane and 1,1,1,3,5,5,5-heptamethyltrisiloxane, the possibility of obtaining
exo
-isomers of norbornenes with 100
exo
-/
endo
-selectivity is shown. The investigation of Pt-, Rh-, and Pd-complexes in combination with various ligands as catalysts was performed. The hydrosilylation of norbornadiene-2,5 in the presence of Pt- or Rh-catalysts was not selective and led to a mixture consisting of three isomers (
exo
-/
endo
-norbornenes and substituted nortricyclane). In the case of the Pd-salt/ligand catalytic system, the formation of an
endo
-isomer was not observed at all and only two isomers were formed (
exo
-norbornene and nortricyclane). The selectivity of
exo
-norbornene/nortricyclane formation strongly depended on the nature of the ligand in the Pd-catalyst. The best selectivity was revealed when
R
-MOP was the ligand, while the highest catalytic activity was reached with a dioxalane-containing ligand.
A simple one-step approach for the selective synthesis of
exo
-norbornenes with organosilicon substituents is suggested through the direct hydrosilylation of norbornadiene-2,5 with chlorine-free silanes.
IL-11 is multifunctional cytokine whose physiological role in the lungs during pulmonary tuberculosis (TB) is poorly understood. Here, using in vivo administration of specific antibodies against ...IL-11, we demonstrate for the first time that blocking IL-11 diminishes histopathology and neutrophilic infiltration of the lung tissue in TB-infected genetically susceptible mice. Antibody treatment decreased the pulmonary levels of IL-11 and other key inflammatory cytokines not belonging to the Th1 axis, and down-regulated IL-11 mRNA expression. This suggests the existence of a positive feedback loop at the transcriptional level, which is further supported by up-regulation of IL-11 mRNA expression in the presence of rIL-11 in in vitro cultures of lung cells. These findings imply a pathogenic role for IL-11 during the early phase of Mycobacterium tuberculosis-triggered disease in a genetically susceptible host.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Correction for 'The selective hydrosilylation of norbornadiene-2,5 by monohydrosiloxanes' by Marina A. Guseva
et al.
,
RSC Adv.
, 2019,
9
, 33029-33037.
Modeling of the Vegetable Oil Blends Composition Voskanyan, Olga S; A., Igor; A., Marina ...
International journal of advanced computer science & applications,
2019, Letnik:
10, Številka:
8
Journal Article
Odprti dostop
The article presents a computer modeling of blends of vegetable oils for treatment-and-prophylactic and healthy nutrition. To solve this problem, based on biomedical requirements, models of vegetable ...oil blends have been developed, taking into account the required chemical composition, mass fractions of the main components of the product, structural correlations of the biological value of blends according to the criterion of fatty acid compliance (omega-6 to omega-3). The problem was solved by the method of complete enumeration (brute force), which belongs to the class of methods for finding a solution by exhausting all sorts of options. An automated research system has been developed and implemented to model the composition of mixtures of vegetable oils in accordance with a given target function of the ratio of omega-6: omega-3 polyunsaturated fatty acids (PUFAs). The use of an automated system allowed us to model prescription formulations of blends of oils, taking into account the constraints set and a given goal function. In this study, three alternatives were obtained for a blend composition with omega-6: omega-3 in the first and second variant 5: 1, and in the third - 10: 1, which makes it possible to use them for healthy and therapeutic nutrition.
Well-defined single-component and tolerant Ru-, Mo-, and W-catalysts have been earlier developed for ring-opening metathesis polymerization of norbornene and its derivatives. Another way of ...norbornene polymerizationvinyl-addition polymerization (VAP)is a more thermodynamically favorable process and gives polymers with saturated and rigid main chains. Single-component catalysts for VAP are required, which combine good activity, tolerance to functional groups, resistance to oxygen, and air moisture and are capable of catalyzing living VAP of norbornenes. Herein, we have shown that cationic Pd-complexes with N-heterocyclic carbene ligands (NHC ligands) and weak coordinating anion ligands ((NHC)Pd(allyl)L+A–, where allyl is an allyl group, L = CO, CH3CN, CH2Cl2, and A– = SbF6 – or BARF–) are highly efficient single-component catalysts for VAP of both norbornene and various substituted norbornenes. These complexes, being stable in the solid state and in solutions, have exhibited several important features as VAP catalysts. They are capable of catalyzing VAP of norbornenes in air and are tolerant to functional groups. The complexes have shown high catalytic activity and have allowed polymerizing monomers at very low catalyst loadings, as low as 2 ppm. The versatility of (NHC)Pd(allyl)L+A– complexes as catalysts of VAP has been demonstrated by successful polymerization of monomers with polar and bulky groups, containing alkyl, vinyl, alkylidene, ether, ester, imide, or organosilicon motifs, affording high-molecular-weight products in good and high yields. Tuning the nature of NHC and allyl ligands in (NHC)Pd(allyl)L+A– complexes let perform living VAP, yielding block copolymers.
Silicon-substituted polynorbornenes are an unusual class of polymeric membrane materials, combining the properties of both glassy and rubbery polymers. They exhibit an attractive performance for ...CO2/N2 separation and for separation of gaseous hydrocarbons. However, addition polynorbornenes with Si-groups (for examples, having Si–O–C, or Si–O–Si-spacers) often suffer from poor film-forming properties due to low molecular weights of the polymers. Herein, by using a new simple and efficient approach to the synthesis of such polymers, we prepared two sets of novel high-molecular-weight polymers based on pure exo-isomers of Si-containing norbornenes and studied their gas transport properties in detail. The desired metathesis and addition polynorbornenes with (C2H5)3Si-, (CH3)3SiO(CH3)2Si- and ((CH3)3SiO)2(CH3)Si-side groups were readily obtained in good or high yields via selective hydrosilylation of norbornadiene-2,5 by commercial silanes followed by polymerization over Ru- or Pd-catalyst. Diffusion (D) and permeability (P) coefficients of these polynorbornenes were determined for permanent gases (He, H2, O2, N2, CO2) and C1–C4 alkanes. The influence of exo-/endo-orientation of substituents on gas transport properties and the relationship between nature of side-groups and membrane properties were evaluated. The data on BET, SEM, WAXD, and fractional free volumes of the polymers are also reported and discussed.
Display omitted
•A simple and selective approach to Si-substituted poly(exo-norbornenes) was developed.•Structure property study of poly(siloxanylnorbornenes) for C4H10/CH4 separation.•Si–O–Si-moieties improved light hydrocarbons permeability.•Effect of exo-/endo-orientation of substituent on gas permeability was studied.
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