[Contamination of surgical wound during tracheal resection depending on the mode of mechanical ventilation]. / Kontaminatsiya operatsionnoi rany v zavisimosti ot varianta IVL pri rezektsii trakhei.

OBJECTIVE: To analyze contamination of surgical wound during tracheal resection depending on the mode of mechanical ventilation. MATERIAL AND METHODS: There were 976 patients. Circular tracheal resection was made in 396 of these patients. RESULTS: Overall postoperative morbidity was 15.7%, mortality - 0.8%. Bacteriological examination of surgical wound was performed before tracheotomy and after formation of anastomosis depending on the method of mechanical ventilation. Surgical field was sterile before tracheotomy in all cases, contamination was confirmed after tracheotomy in all patients. Minimal contamination was observed in case of apneic oxygenation (100 times less than volumetric mechanical ventilation or high frequency mechanical ventilation). In all cases, several species of pathogenic microorganisms were identified. The number of species was also minimal in case of hypnotic mechanical ventilation. CONCLUSION: Contamination does not directly affect the development of local purulent-inflammatory process. However, this factor should not be ignored and compliance with all preventive measures is required.

[Etiology, diagnosis and treatment of cicatricial tracheal stenosis]. / Etiologiya, diagnostika i lechenie rubtsovogo stenoza trakhei.

Development of tracheal surgery was associated with introduction of fundamentally new procedures: two-level reconstruction, redo tracheal resection, tracheal resection with simultaneous dissection of tracheoesophageal fistula. There are combined and staged techniques when tracheal repair or endoscopic interventions are performed as a stage before circular resection of trachea. However, a single algorithm for prevention and correction of postoperative complications is still absent in tracheal surgery. Further development of tracheal surgery directly depends on introduction of preventive measures and analysis of adverse factors associated with increased risk of complications. In this regard, ongoing researches in this area are very perspective.

[Tracheolaryngeal resection for cicatricle stenosis]. / Trakheogortannaia rezektsiia pri rubtsovom stenoze.

AIM: To determine the safest and the most effective surgical treatment of patients with cicatricle stenosis of tracheolaryngeal segment via analysis of different approaches. MATERIAL AND METHODS: For the period 1963-2015 at Petrovsky Russian Research Center for Surgery and Sechenov First Moscow State Medical University 1128 patients with cicatricle tracheal stenosis have been treated. There were 683 men and 445 women. 684 (60.6%) patients were young and the most employable (21-50 years). All patients were divided into 2 groups depending on time of treatment: the first one included 297 patients between 1963 and 2000, the second group - 831 patients between 2001 and 2015. In group 1 tracheolaryngeal anastomosis was made in 10 (16.9%) out of 59 patients who underwent tracheal resection. Previously indication for this surgery was cicatricle stenosis of cervical trachea and larynx with upper borderline of cicatricle changes at least 2 cm from vocal folds. In group 2 these procedures were more frequent. 94 (28.5%) out of 330 patients underwent tracheolaryngeal resection. Cranial borderline of lesion was within 0.5 cm from the vocal folds (only if posterior laryngeal wall at the level of cricoid cartilage was intact). Difficult patients are those who need for double-level or redo repair and procedures with tracheostomy. RESULTS: In the second group overall morbidity after tracheal resections followed by anastomosis was 5.6%. These complications were more common after tracheolaryngeal anastomosis (17%). There were no lethal outcomes after 94 tracheolaryngeal resections. Good long-term results were observed in 89.8% of patients after circular resection. Their quality of life was similar to that of healthy people. Preserved cicatricle tracheal segments during tracheal repair with T-shaped airway tube adversely affects quality of life in these patients in long-term period.

[POSTRESUSCITATION CICATRICIAL TRACHEAL STENOSIS. CURRENT STATE OF THE PROBLEM - THE SUCCESSES, THE HOPES AND DISAPPOINTMENTS.]

BACKGROUND: Currently, the trend continues to increase the number ofpatients with cicatricial tracheal stenosis (CTS). Therefore, prevention and treatment ofthis disease remains topical. The main cause ofcicatricial tracheal stenosis is damaging the trachea during mechanical ventilation. The scheme ofprevention of this disease in Russia hasn't brought the desired results. THE AIM: to clarify the modern etiology of cicatricial tracheal stenosis, to identify the trend in incidence rates, to determine whether there is an optimal safe alternative to tracheostomy including the use of minimally invasive techniques, to improve diagnostic and therapeutic algorithm at various stages of assistance, and also to study the results of innovative operations and new ways of maintaining gas exchange. MATERIALS AND METHODS: 1128 patients with cicatricial tracheal stenosis was treated from 1963 to 2015 in Petrovsky National Research Centre of Surgery and IMSechenov First Moscow State Medical University. Over time methods of di- agnosis, methods of anesthesia and operations have been varied. In this regard all patients were divided into two groups depending on the period of time from 1963 to 2000 (297 patients) andfrom 2001 to 2015 (831 patients). In recent decades there is a steady increase in the number of treated patients. So, if in the first group during the year operational treatment about the CTS 8,0 patients were underwent, in the second - to 55.4. Cicatricial tracheal stenosis appeared after lung mechanical ventilation at 1025 (for 90.9%) patients. They have undergone both radical one-stage treatment and multi-stage and sequential intraluminal procedures. In general there is a clear trend towards more aggressive surgical tactics. So, if in thefirst group, the tracheal resection with anastomosis was performedin 59 patients only, the second-330. Thefrequency ofpostoperative complications and mortality in the second group ofpatients was 12.9 and 0.7 %, respectively. RESULTS: Only a reasonable combination of all treatment methods, the principle of "every patient his own version of operation" allows to minimize the risk oftreatment and to get a good lasting result. Proof of such provision may be the fact that the frequency of complications and postoperative mortality at our patients have had a tendency to decrease and currently stands at 12.9 and 0.7 %, respectively for many years. It is 2.3 and 9.6 times less, respectively, than in the periodfrom 1963 to 2000. It appears that further reduction of these indicators will be at a slower pace, afurther solution of the CTS problem will be based on the prevention of disease. CONCLUSION: Prevention of cicatricial tracheal stenosis in the departments of reanimation and intensive care is currently inadequate. It requires fundamentally new approaches, but reform still has not brought the desired results. Diagnosis of the CTS at an early stage allows early treatment and to avoid complex and risky operations. Increasingly important, apart tracheoscopy for diagnosis of tracheomalacia purchase dynamic computed tomography and magnetic resonance - tomography. Treatment ofpatients with CTS requires a multidisciplinary approach, individual selection operations for a particular patient. The general trend of the further development of tracheal surgery is associated with an increase in the number of simultaneous resections, including at the long, two-level stenosis, as well as at relapse. The patients who had refused treatment or have elected him palliative options made possible surgery. The frequency of postoperative comnlications and mortality decreased significantiv, including after extensive and traumatic operations on the trachea.

[Clinical efficacy of the biospecific hemosorbent "Liposorb"].

The aim of the present work was to evaluate clinical efficacy of the biospecific hemosorbent "Liposorb". The main component of "Liposorb" is polyacrylamide gel containing an immobilized affine ligand (antibiotic polymyxin E-colistyne). 40 patients with abdominal sepsis and peritonitis of different genesis underwent a total of 52 seances of vein-venous extracorporeal hemoperfusion of hemosorbent "Liposorb". Endotoxin level (lipopolysaccharide - LPS) was measured by the turbodimetric method. Blood perfusion through a "Liposorb" column at 50-70 ml/min during 90 minutes permitted to reach stabilization of parameters of systemic hemodynamics. All the patients showed positive dynamics of general well-being, blood gas composition, clinical and biochemical blood analyses. The endotoxin (LPS) level of Gramm-negative flora significantly decreased. It is concluded that hemosorbtion using biospecific polymyxin-containing hemosorbent "Liposorb" effectively removes Gramm-negative endotoxin and leads to stabilization of hemodynamic in patients with Gramm-negative abdominal sepsis.

Engineering charge selectivity in alamethicin channels.

The peptide alamethicin provides a system for engineering ion channel charge selectivity. To define alamethicin charge selectivity experimentally, we measured single-channel current-voltage relationships in KCl gradients using covalently linked peptide dimers. Two factors were found to contribute to the charge selectivity of these channels: (i) the ionic strength of the surrounding solutions; and (ii) the distribution of fixed charge on the peptide. Native alamethicin channels exhibited either cation selectivity or anion selectivity depending on which end of the channel was at the low salt side of the membrane. When the glutamine residue at position 18 in the sequence was replaced with a lysine residue, an anion-selective channel was obtained regardless of which end of the channel was at the low salt side of the membrane.

An anion-selective analogue of the channel-forming peptide alamethicin.

The peptide alamethicin self-assembles to form helix bundle ion channels in membranes. Previous macroscopic measurements have shown that these channels are mildly cation-selective. Models indicate that a source of cation selectivity is a zone of partial negative charge toward the C-terminal end of the peptide. We synthesized an alamethicin derivative with a lysine in this zone (replacing the glutamine at position 18 in the sequence). Microscopic (single-channel) measurements demonstrate that dimeric alamethicin-lysine18 (alm-K18) forms mildly anion-selective channels under conditions where channels formed by the parent peptide are cation-selective. Long-range electrostatic interactions can explain the inversion of ion selectivity and the conductance properties of alamethicin channels.

Voltage-dependent behavior of a "ball-and-chain" gramicidin channel.

The channel-forming properties of two analogs of gramicidin, gramicidin-ethylenediamine (gram-EDA), and gramicidin-N,N-dimethylethylenediamine (gram-DMEDA) were studied in planar lipid bilayers, using protons as the permeant ion. These peptides have positively charged amino groups tethered to their C-terminal ends via a linker containing a carbamate group. Gram-DMEDA has two extra methyl groups attached to the terminal amino group, making it a bulkier derivative. The carbamate groups undergo thermal cis-trans isomerization on the 10-100-ms time scale. The conductance behavior of gram-EDA is found to be markedly voltage dependent, whereas the behavior of gram-DMEDA is not. In addition, voltage affects the cis-trans ratios of the carbamate groups of gram-EDA, but not those of gram-DMEDA. A model is proposed to account for these observations, in which voltage can promote the binding of the terminal amino group of gram-EDA to the pore in a "ball-and-chain" fashion. The bulkiness of the gram-DMEDA derivative prevents this binding.

[Hemocarboperfusion in the treatment of patients with an opiate abstinence syndrome]. / Gemokarboperfuziia v lechenii bol'nykh s opiinym abstinentnym sindromom.

The authors analyze of the results of applying hemocarboperfusion in treatment of opiate addiction. All the patients were treated in the Belorussian center of sorption methods of detoxication and plasmapheresis. It is shown that 4-5 procedures of hemocarboperfusion in combination with infusion and drug therapy allow to correct of withdrawal mental and somatic disorders.

[Rhodopsin photo-oxidation: oxygen consumption and spectrum of activity]. / Fotookislenie rodopsina: raskhod kisloroda i spektr deistviia.

The coincidence of action spectrum of SH-groups and lipid oxidation is shown in the photoreceptor photodamaging process. Dose dependence of the process is measured in the maximum of photooxidation (380 nm). Dose of 0.1 J/cm2 is the threshold of photodamaging of photoreceptor membrane. Oxygen consumption in photooxidation of rhodopsin SH-groups and lipids are determined.

[The study of photo-induced rhodopsin aggregation in the photoreceptor membrane by electron paramagnetic resonance]. / Issledovanie svetoindutsirovannoi agregatsii rodopsina v fotoretseptornoi membrane metodom élektronnogo paramagnitnogo rezonansa.

The ESR measuring of UV-induced free radicals concentration limit has been used for studying rhodopsin aggregate state in the photoreceptor membrane.

[Retinal-sensitized photo-oxidation of rhodopsin]. / Sensibilizirovannoe retinalem fotookislenie rodopsina.

Kinetics of retinal photosensitized initiation of radicals of sulfhydryl groups of cysteine and rhodopsin is investigated by spin trapping. Photooxidation of both systems is the result of free radical mechanism. Photooxidation of SH-groups proceeds both with singlet oxygen participation and by direct interaction of photosensitizer with the substrate. The rate constants of these reactions are measured. The rate constant with oxygen participation (K0 = 1.1 X 10(9) M-1 S-1) is higher than the one without oxygen (K = 2.5 X 10(8) M-1 S-1) correspondingly. The lifetime of retinal triplet state in photoreceptor membrane is tau = 4 X 10(-6) s.

[Mechanism of glutathione oxidation by photosensitized retinal]. / Mekhanizm fotosensibilizirovannogo retinalem okisleniia gliutationa.

Sulphur radicals appearing in the retinal photosensitized glutathione oxidation have been recorded by spin trapping. There is no reaction in the absence of oxygen. That is why the single oxygen is supposed to take part in the reaction (IId type photosensitized reaction).