[Pathogenetic approaches to the correction of vascular homeostasis in patients with COVID-19: A review].

The adverse outcomes in patients with COVID-19 in the initial phase of the disease are often due to the development of cytokine storm, endothelial dysfunction, shifts in the hemostasis system, microangiopathy, angiocentric inflammation, and pathological angiogenesis, which require targeted therapy. Unfortunately, to date, there is still no drug with proven high efficacy. This review is to analyse the literature data on the pathogenesis of vascular homeostasis lesions and possible ways to correct the existing shifts in patients with COVID-19.

Synthesis of -stereogenic 1-phosphanorbornane-derived phosphine-phosphite ligands and application in asymmetric catalysis.

A convenient synthesis of enantiopure mixed donor phosphine-phosphite ligands has been developed incorporating -stereogenic phosphanorbornane and axially chiral bisnaphthols into one ligand structure. The ligands were applied in Pd-catalyzed asymmetric allylic substitution of diphenylallyl acetate, Rh-catalyzed asymmetric hydroformylation of styrene and Rh-catalyzed asymmetric hydrogenation of an acetylated dehydroamino ester. Excellent branched selectivity was observed in the hydroformylation although low was found.

Ring-Opening Reaction of 1-Phospha-2-Azanorbornenes via P-N Bond Cleavage and Reversibility Studies.

The reactive P-N bond in 1-phospha-2-azanorbornenes is readily cleaved by simple alcohols to afford -chiral 2,3-dihydrophosphole derivatives as a racemic mixture. The isolation of the products was not possible due to the reversibility of the reaction, which could, however, be stopped by sulfurization of the phosphorus atom, thus efficiently blocking the lone pair of electrons, as exemplified for yielding structurally characterized . Additionally, the influence of the substituent in the α position to the phosphorus atom (H, Ph, 2-py, CN) on the reversibility of the reaction was studied.

Access to Enantiomerically Pure -Chiral 1-Phosphanorbornane Silyl Ethers.

Sulfur-protected enantiopure -chiral 1-phosphanorbornane silyl ethers , are obtained in high yields via the reaction of the hydroxy group of -chiral 1-phosphanorbornane alcohol with -butyldimethylsilyl chloride (TBDMSCl) and triphenylsilyl chloride (TPSCl). The corresponding optically pure silyl ethers , are purified via crystallization and fully structurally characterized. Desulfurization with excess Raney nickel gives access to bulky monodentate enantiopure phosphorus(III) 1-phosphanorbornane silyl ethers , which are subsequently applied as ligands in iridium-catalyzed asymmetric hydrogenation of a prochiral ketone and enamide.

Facile Synthesis of Enantiomerically Pure P-Chiral 1-Alkoxy-2,3-dihydrophospholes via Nucleophilic P-N Bond Cleavage of a 1-Phospha-2-azanorbornene.

Invited for the cover of this issue is the group of Prof. Evamarie Hey-Hawkins at Leipzig University. The image depicts a deer with diastereomeric antlers.

Facile Synthesis of Enantiomerically Pure P-Chiral 1-Alkoxy-2,3-dihydrophospholes via Nucleophilic P-N Bond Cleavage of a 1-Phospha-2-azanorbornene.

The reactive P-N bond in a racemic mixture of endo-1-phospha-2-azanorbornene (PAN) (R /S )-endo-1 is readily cleaved with enantiomerically pure lithium alkoxides followed by protonation to afford diastereomeric mixtures of P-chiral 1-alkoxy-2,3-dihydrophosphole derivatives. The isolation of these compounds is rather challenging due to the reversibility of the reaction (elimination of alcohols). However, methylation of the sulfonamide moiety of the intermediate lithium salts and sulfur protection of the phosphorus atom prevent the elimination reaction.

Clinical and Microbiological Spectra and Therapeutic Outcomes of Polymicrobial Keratitis.

Purpose: The aim of this study was to evaluate the risk factors, microbiology, and treatment outcomes of polymicrobial keratitis (PMK).

Methods: We retrospectively analyzed 65 patients diagnosed with PMK between 2016 and 2019. The clinical and microbiological characteristics and outcomes were evaluated.

Risk factors, clinical features and outcomes of Neisseria keratitis.

Objective: To describe the clinical features, risk factors and outcomes of Neisseria keratitis.

Methods: This is a retrospective observational study wherein medical records of cases with microbiologically proven Neisseria keratitis were reviewed. Data pertaining to the underlying predisposing factors, clinical characteristics of the corneal ulcer, antibiotic susceptibility of the Neisseria species isolate from the corneal scraping, the treatment given, and outcomes were collected and analyzed.

Methanol Sensing by a Luminescent Zinc(II)-Based Metal-Organic Framework.

A luminescent zinc-based metal-organic framework (MOF; 1) was synthesized from a highly conjugated tridentate ligand, 1,3,5-tris[(1E)-2'-(4''-benzoic acid)vinyl]benzene. X-ray single crystal analysis reveals the organization of 1 in a three-dimensional porous framework. Thermogravimetric analysis shows that 1 has a good thermal stability, and resists decomposition up to 420 °C.

[Assessing resveratrol effect on ocular blood flow in experiment].

Aim: To study the effect of resveratrol on ocular blood flow in vivo in healthy rats and those that underwent retinal ischemia/reperfusion.

Material And Methods: The experimental study was performed on 40 Wistar rats (40 eyes). For ocular blood flow evaluation, color Doppler imaging (CDI), power Doppler (PD), and pulsed-wave spectral Doppler ultrasonography were performed using the Voluson E8 Expert ultrasonic diagnostic system (GE Healthcare).

[DYNAMICS OF TWENTY-FOUR HOUR MONITORING OF BLOOD PRESSURE IN ELDERLY PATIENTS WITH BRONCHIAL ASTHMA].

Twenty-four hour blood pressure monitoring in groups of patients of elderly age with bronchial asthma and hypertension was conducted. The study showed an increased variability of blood pressure and insufficient reduction in night time that leads to development of cardiovascular complications.

[Ocular blood flow and retinal electrogenesis in retinitis pigmentosa].

Aim: to investigate correlations between changes in ocular hemodynamics revealed by color Doppler flow mapping (CDFM) and pulsed-wave (PW) Doppler imaging, one the one hand, and electrical activity of the retina, on the other, in patients with early, moderate, and severe retinitis pigmentosa (RP).

Material And Methods: A total of 20 patients (40 eyes) aged from 16 to 40 years (28.4 ± 8.

[Methods of ocular microcirculation assessment in experimental animals].

The review discusses some of the most common methods of ocular microcirculation assessment in animals: fluorescent and indocyanine green angiography, scanning laser ophthalmoscopy with various dyes, laser Doppler flowmetry and velocimetry, color and power Doppler imaging, and pulsed-wave spectral Doppler ultrasonography. Each method possesses certain advantages and disadvantages, thus, the choice between them depends on the purposes and objectives of the given experimental study.

[Ultrasonography in normal eyelids assessment].

The article presents the results of a complex study on ultrasonography which included high-resolution grey scale B-scan, color Doppler imaging, and ultrasonic density measurement of eyelids and periorbital tissues. A total of 48 patients were enrolled. Echographic anatomy of eyelid layers, i.

[Autonomic regulation of cardiac rhythm in elderly patients with bronchial asthma].

Evaluation of independent and combined interrelations of bronchial obstruction and autonomic regulation of cardiac rhythm in elderly patients with bronchial asthma was carried out. Positive correlation of the extent of bronchial obstruction and decrease of absolute indices of cardiac rhythm variability was established.