Эффективность и безопасность резекции стенки мочевого пузыря с опухолью единым блоком с использованием тулиевого волоконного лазера «Уролаз»

Background. The high recurrence rate after conventional transurethral resection (cTUR) for bladder cancer (BC) requires search for more effective methods of surgical treatment. Objective: to evaluate the feasibility, safety, and efficacy of cTUR versus thulium laser en bloc resection of bladder tumors using new fiber laser “Urolaz”.Materials and methods. 129 patients, who underwent surgical treatment for BC between 2015–2017 in urological department of I.M. Sechenov First Moscow State Medical University were included in the study. The cTUR were performed for 58 patients, 71 patients underwent thulium laser en bloc resection of bladder tumors.Results. The presence of detrusor muscle in specimen was 58.62 % in cTUR group and 91.55 % in thulium laser en bloc resection group respectively. Obturator nerve reflex, bladder perforation, and bleeding in thulium laser en bloc resection group were absent, therefore immediate instillation of chemotherapy was made in all these cases. Recurrence rate after 12 and 18 months after surgery in the group of en bloc resection was statistically lower compared to the cTUR group.Conclusion. The results, obtained in our study shows that thulium en bloc resection using thulium fiber laser “Urolaz” is feasible, effective and safe procedure for patients with BC. Thulium en bloc resection has a number of advantages over the cTUR: absence of obturator nerve reflex, high quality of specimen for pathological examination (presence of detrusor muscle in specimen was 91.55 %) and low recurrence rate.Введение. Высокая частота рецидивирования рака мочевого пузыря (РМП) после традиционной трансуретральной резекции (ТУР) заставляет вести поиски более эффективных методов оперативного лечения.Цель исследования – оценка выполнимости, эффективности и безопасности резекции стенки мочевого пузыря с опухолью единым блоком (en bloc) с использованием тулиевого волоконного лазера «Уролаз».Материалы и методы. В НИИ уронефрологии и репродуктивного здоровья человека Первого МГМУ им. И. М. Сеченова за период 2015–2017 гг. были прооперированы 129 пациентов по поводу мышечно-неинвазивного РМП. ТУР выполнена 58 пациентам, лазерная тулиевая резекция en bloc – 71 пациенту.Результаты. Клетки мышечного слоя в макропрепарате были представлены в 58,62 % наблюдений в группе ТУР и в 91,55 % случаев в группе лазерной резекции en bloc. Обтураторный рефлекс и связанные с ним перфорации и кровотечения в группе лазерной тулиевой резекции en bloc отсутствовали, благодаря чему всем пациентам данной группы была выполнена немедленная инстилляция химиопрепарата. Частота развития рецидивов через 12 и 18 мес после операции в группе резекции en bloc оказалась статистически значимо ниже по сравнению с группой ТУР.Заключение. Полученные результаты показывают, что тулиевая резекция en bloc с помощью волоконного лазера «Уролаз» выполнима, эффективна и безопасна в рамках лечения пациентов с РМП без инвазии в мышечный слой и имеет ряд преимуществ перед ТУР, а именно отсутствие обтураторного рефлекса, качественный материал для патоморфологического исследования (присутствие клеток мышечного слоя до 91,55 %), низкая частота развития рецидивов

Nucleophile specificity in α-chymotrypsin- and subtilisin-(Bacillus subtilis strain 72) catalyzed reactions

Nucleophilic properties of amino-acids were studied systematically in acyl-transfer reactions catalyzed by α-chymotrypsin and subtilisin from Bacillus subtilis strain 72 (subtilisin 72) using Mal-l-Ala-l-Ala-l-PheOMe as the acyl-group donor. In α-chymotrypsin-catalyzed reactions, the nucleophile reactivities increase in the following order: d-AlaNH2 < GlyNH2 < l-AlaNH2 < l-ScrNH2 < l-ThrNH2 < l-HisNH2 < l-ValNH2 < l-LcuNH2 < l-TrpNH2 < l-MetNH2 < l-NvaNH2 < l-PheNH2 < l-IleNH2 < l-TyrNH2 < l-ArgNH2. In reactions catalyzed by subtilisin 72, the reactivities increase as follows: l-LeuNH2 < l- IleNH2 < l-ThrNH2 < l-ArgNH2 < l-TrpNH2 < l-NvaNH2 < l-ValNH2 < l-MctNH2 < l-AlaNH2 < l-ScrNH2 < d-AlaNH2 < GlyNH2. In α-chymotrypsin-catalyzed reactions, hydrophobic interactions are entirely responsible for the differences between the reactivity of the nucleophiles for amides of all the amino-acids tested with the exception of d-AlaNH2, l-ArgNH2 and l-TyrNH2. In the reactions catalyzed by subtilisin 72, Amino-acid side-chain characteristics and the nucleophile reactivities are not related. The data obtained show the low selectivity of the S1′ subsite of subtilisin 72 and high specify of this subsite in α-chymotrypsin

Side reactions in enzymatic peptide synthesis in organic media : Effects of enzyme, solvent, and substrate concentrations

The progress of enzymatic peptide synthesis catalyzed by α-chymotrypsin and subtilisin from Bacillus subtilis strain 72 (subtilisin 72) in low-water systems was studied. The initial reaction mixture consisted of the solvent, the acyl-group donor (MalAlaAlaPheOMe or ZAlaAlaPheOMe, Mal, maleyl, Z, benzyloxycarbonyl), the nucleophile XaaNH2 (Xaa = Phe, Leu or Ala), and the enzyme adsorbed on porous silica material. All amino acid residues were of the l-configuration. The solvent consisted of acetonitrile, dimethylformamide (DMF), and 4% (v/v) of water. The DMF/acetonitrile ratio was varied between 0 and 1/1. At high concentration of the acyl-group donor and approximately equimolar ratio of the nucleophile and the acyl-group donor, quantitative formation of MalAlaAlaPheXaaNH2 or ZAlaAlaPheXaaNH2 occurred. As a result, a method for the synthesis of polypeptide amides was developed. At low concentration of the acyl-group donor and excess of the nucleophile, the condensation by-products with two and three nucleophile molecules were found in the reaction mixtures. The data obtained provided evidence that organic solvents affected the S'1-specificity of α-chymotrypsin and the Sl-specificity of subtilisin 72, while the Sl-specificity of α-chymotrypsin and the S'l-specificity of subtilisin 72 were not affected. When the DMF content was increased, the rate of the α-chymotrypsin-catalyzed reactions decreased. In contrast to this, an increase in DMF content accelerated the subtilisin 72-catalyzed reactions. Hydrolysis of the acyl-group donor did not occur in the α-chymotrypsin-catalyzed reactions. Significant (up to 50%) formation of MalAlaAlaPheOH was observed a the early stage of the subtilisin 72-catalyzed reactions. Later MalAlaAlaPheOH underwent synthesis

Synthesis and X-ray Structural Study of 1-adamantylmethyl 2-cyanoacrylate and 1,10-decanediol bis-2-cyanoacrylate

I-Adamantylmethyl 2-cyanoacrylate (1) was prepared by the reaction of 2-cyanoacryloyl chloride with 1-adamantylmethanol . 1,10-Decanediol bis-2-cyanoacrylate (2) was synthesized by transesterification of methyl 2-cyanoacrylate with 1,10-decanediol. Esters1 and2 were studied by X-ray structural analysis

Electrochemical Deposition of Ni–W Crack-Free Coatings

The main features of electrochemical deposition of coatings based on Ni&ndash;W binary alloy in the pulse current mode using pyrophosphate electrolytes were studied. Two electrolytes with a pH of 8.7 and 9.5 were used. The deposition was carried out with the current density varying in the range of 0.01&ndash;0.1 A&middot;cm&minus;2, and the duty cycle (the relative pulse duration) was changed within the range 20&ndash;100%. The surface morphology and elemental and phase composition of the coatings were studied by scanning electron microscopy, energy-dispersive X-ray microanalysis and X-ray diffractometry. The experimental conditions allowing us to achieve the maximum Faradaic efficiency and W content in the coatings were determined. It was found that the pulse current mode enabled the fabrication of crack-free coatings with a thickness greater than 6 &mu;m