Epidemiologic surveillance control issues and optimization methods of nosocomial purulent-septic infections of newborns and women in labor

Department of Epidemiology, E. A. Vagner State Medical Academy of Perm, RussiaThe problems of nosocomial purulent–septic infections (NPSI) in newborns and women in labour still appear to be actual for public health care system because of NPSI wide distribution and their social and economic affection. The undertaken studies have revealed that true NPSI morbidity of the newborns and women in labor exceeds the data in official documents by 10 times. During continuous microbiological screening of the material taken from patients and from hospital environmental objects it has been established that the epidemic NPSI niduses are caused by the circulation of nosocomial strains. Extra hospital strains dо not provoke infectious and inflammatory processes development in 70.4% of cases. Extra hospital strains cause individual NPSI maladies in 21.0% of cases and only in 1.9% they form the epidemic centres of two and more cases. The research shows that the INPSI agents isolated from the medical wastes after disinfection, in comparison with the microorganisms isolated before the disinfection process, are characterized by virulence and the resistance to poly-antibiotics and used disinfectant. Therefore, in the absence of patients with NPSI signs in a particular in-patient department, the identification of microorganisms’ strains can be carried out by a usual bacteriological examination of disinfected hospital wastes. In conditions of medical preventive institutions and the medical insurance system NPSI damage can be economically determined by laboratory expenses, antibacterial and general health treatment expenses, plus the basic tariffs without the average examination and treatment costs. Проблемы внутрибольничных гнойно-септических инфекций (ВГСИ) у новорождённых и рожениц по-прежнему остаются актуальными для здравоохранения ввиду их широкого распространения и социально-экономической значимости. Исследования показали, что истинная заболеваемость ВГСИ у новорождённых и рожениц в 10 раз выше официально зарегистрированной. Продолжительное микробиологическое исследование материала, взятого у больных и из объектов больничной среды, показало, что эпидемические очаги ВГСИ связаны с циркуляцией внутрибольничных штаммов. Внебольничные штаммы в 70,4% случаев не вызывают развития инфекционных или воспалительных процессов. Эти штаммы вызывают отдельные заражения ВГСИ в 21% случаев и только в 1,9% случаев формируют эпидемические очаги с двумя и более числом заболевших. Исследования показывают, что возбудители, выделенные из медицинских отходов после дезинфекции, в отличие от микроорганизмов, изолированных до дезинфекции, характеризуются вирулентностью, а также полиантибиотикорезистентностью и устойчивостью к используемому дезинфектанту. Таким образом, при отсутствии в частной клинике пациентов с признаками ВГСИ идентификация микробных штаммов может быть проведена при помощи обычного бактериологического исследования дезинфицированных медицинских отходов. В условиях медицинских профилактических учреждений и системы медицинского страхования экономический ущерб от ВГСИ может быть оценён по лабораторным затратам, стоимости общего и антибактериального лечения, плюс базовые тарифы без средней стоимости обследования и лечения

Effect produced by thickness of nanolayers of multilayer composite wear-resistant coating on tool life of metal-cutting tool in turning of steel AISI 321

The paper considers multilayer composite nano-structured Ti-TiN-(Ti,Al,Cr,Si)N coatings for metal-cutting tools. The coatings under the study mechanical characteristics of the coatings were studied, and the tool life tests were carried out for carbide tools with the above coatings for dry about 80 nm). The turning of steel AISI 321(HB 180) at vc = 100, 150, and 200 m/min (f=0.11 mm/rev; ap=0.5 mm). Uncoated tools and tools with Ti-(Ti,Al)N coatings of traditional type were used as objects of comparison. The studies have found out that coatings with thinner nanolayers demonstrate better performance properties, especially at higher cutting speeds. © 2018 The Authors. Published by Elsevier Ltd

УПРОЧНЕНИЕ ТВЕРДОСПЛАВНОГО ЛЕЗВИЙНОГО ИНСТРУМЕНТА, ИСПОЛЬЗУЕМОГО ДЛЯ РЕЗАНИЯ ТРУДНООБРАБАТЫВАЕМЫХ ТИТАНОВЫХ СПЛАВОВ И ХРОМОНИКЕЛЕВЫХ СТАЛЕЙ, МНОГОСЛОЙНЫМИ НАНОСТРУКТУРНЫМИ ПОКРЫТИЯМИ

Complex investigations into physicomechanical properties and adhesion strength in the «coating–carbide cutting insert» system of monolayered (Ti–Al–N) and multilayered (Ti–Al–N/Cr–N, Ti–Al–N/Zr–N/Cr–N) are performed. The advantage of using the latter; which is associated with the passage from the adhesion mechanism of coating destruction to the cohesion mechanism; with an increase in parameters H3/E2 and H/E that characterize the material resistance to plastic and elastic deformation, respectively; is shown. The introduction of chromium into the composition of Ti–Al–N coatings provides a decrease in friction coefficient (from 0,52 to 0,45) and a decrease in probability of adhesion interaction with the treated material. Comparative operational tests of carbide cutting insets (CCI) with coatings under study in the course of continuous cutting steel 12H18N10Т showed that largest wear resistance of Ti–Al–N/Zr–N/Cr–N coatings. Wear tests of CCIs made of VK6NST and TT10K8B alloys with Ti–Al–N/Zr–N/Cr–N coatings in the course of longitudinal turning steel 12H18N10Т and VT20 alloy evidence an increase in their resistance up to a factor of 3,0–3,5 both at low and high cutting rates. These coatings provide an increase in resistance of cutting tool and in milling operations of VT20 titanium alloy at cutting velocity up to 40 m/min.Проведены комплексные исследования физико-механических свойств и адгезионной прочности в системе «покрытие – твердосплавная подложка» монослойных (Ti–Al–N) и многослойных (Ti–Al–N/Cr–N, Ti–Al–N/Zr–N/Cr–N) покрытий. Показано преимущество использования последних, которое связано с переходом от механизма адгезионного разрушения покрытия к когезионному, с повышением параметров H3/E2 и H/E, характеризующих сопротивление материала пластической и упругой деформации соответственно. Введение в состав покрытий Ti–Al–N хрома обеспечивает снижение коэффициента трения (c 0,52 до 0,45) и уменьшение вероятности адгезионного взаимодействия с обрабатываемым материалом. Сравнительные эксплуатационные испытания твердосплавных сменных многогранных пластин (СМП) с исследуемыми покрытиями при непрерывном резании стали 12X18H10Т показали наибольшую износостойкость покрытий Ti–Al–N/Zr–N/Cr–N. Стойкостные испытания СМП из сплавов ВК6НСТ и ТТ10К8Б с покрытиями Ti–Al–N/Zr–N/Cr–N при продольном точении стали 12Х18Н10Т и сплава ВТ20 свидетельствуют об увеличении их стойкости до 3,0–3,5 раз как при низких, так и высоких скоростях резания. Данные покрытия обеспечивают повышение стойкости режущего инструмента и на операциях фрезерования титанового сплава ВТ20 при скорости резания до 40 м/мин

High prevalence of genotype B0/W148 of Mycobacterium tuberculosis among HIV-TB patients in Perm Krai and Irkutsk Region

Background. The population with HIV-infection plays significant role in ongoing tuberculosis pandemic. Immunosuppression due to HIV-infection is one of the causes of TB disseminated forms in this group of people. Having low immune status is also often associated with a polyclonal M. tuberculosis infection. Aim of the research: comparative assessment of epidemic genotypes of M. tuberculosis prevalence and mixed genotypes identification within HlV-TB co-infected patients in two Russian regions. Materials and methods. The DNAs of 78 clinical isolates from Irkutsk Region (IR) and 64 strains from Perm Krai (PK) have been genotyped by MIRU VNTR 24 and RD105/RD207. Strains were obtained from patients who did not have significant age and sex differences. In the PK age of the patients was 34.5 ± 0.9, in IR - 34.4 ± 1.5 years. The samples were obtained from 67.2 and 65.4 % of men, respectively. Result. The study of the M. tuberculosis indicates significant predominance of Beijing genotype strains in patients with TB-HIV of PK (92.2 %) compared to the IR (59.5 %) (х2 = 18.0; p < 0.01). The prevalence of MDR pathogens in TB-HIV patients exceeded 50 %. The mixed genotype detection in the PK and IR was high (14.1 and 12.7 % respectively). The level of virulent strains B0/W148 was 34.4 % in PK patients and 25.3 % in IR ones. Analysis of the results suggests the epidemic spread of MDR-TB in the immunocompromised individuals. Conclusions: The identified trends may indicate that Perm Kray have a process of active dissemination of transmissible strains of M. tuberculosis within HIV-infected population

ТВЕРДОСТЬ, АДГЕЗИОННАЯ ПРОЧНОСТЬ И ТРИБОЛОГИЧЕСКИЕ СВОЙСТВА АДАПТИВНЫХ НАНОСТРУКТУРНЫХ ИОННО-ПЛАЗМЕННЫХ ВАКУУМНО-ДУГОВЫХ ПОКРЫТИЙ (Ti,Al)N–Mo2N

The article reviews the properties of nanostructured multilayer coatings (Ti, Al)N–Mo2N obtained by plasma-ion vacuum arc deposition method (arc-PVD). The thickness of coating layers was comparable to the size of a grain, which was about 30–50 nm. Coating hardness reached 40 GPa with relative plastic work of deformation of about 60 %. It was found by the measuring scratching method that cohesive nature of coating destruction takes place entirely by a plastic strain mechanism, which was the evidence of its high viscosity. Local coating abrasion to a substrate level occurred at a load in the order of 75 N. Under test conditions as per «pin-on-disk» scheme using the opposing Al2O3 element at a load of 5 N, coating friction factor was equal to 0,35 and 0,50 at 20 °C and 500 °C respectively. Besides, it was practically not worn due to formation of MoO3 oxide in the friction zone (Magneli phase) which served as a solid lubricant. The increase in friction factor and appearance of significant wear were observed with further rising of test temperature. Such effect was due to intensified sublimation of MoO3 from friction surfaces with subsequent reduction of its lubricating efficiency.Исследованы свойства наноструктурных мультислойных покрытий состава (Ti,Al)N–Mo2N, полученных методом ионно-плазменного вакуумно-дугового осаждения (arc-PVD). Толщина слоев покрытия сопоставима с размером зерна, который составлял порядка 30–50 нм. Твердость покрытий достигала 40 ГПа с относительной работой пластической деформации около 60 %. Методом измерительного царапания установлено, что когезионный характер разрушения покрытия происходит исключительно по механизму пластического деформирования, что свидетельствует о высокой его вязкости. Локальное истирание покрытия до подложки происходило при нагрузке порядка 75 Н. Коэффициент трения покрытия в условиях испытаний по схеме «стержень–диск» с применением контртела из Al2O3 при нагрузке 5 Н составлял 0,35 и 0,50 при температурах 20 и 500 °C соответственно. При этом оно практически не изнашивалось из-за образования в зоне трения оксида MoO3 (фазы Магнели), работающего в качестве твердого смазывающего материала. При дальнейшем повышении температуры испытания наблюдалось повышение коэффициента трения и появление заметного износа, что связано с интенсификацией процессов сублимации MoO3 с рабочих поверхностей и снижением эффективности его работы как смазывающего материала

On the Efficiency Factors of Positive Law

The article discusses some of the topical theoretical and legal and philosophical and legal problems of lawmaking. According to the author, the efficiency of the application of legislation in the mechanism of legal regulation directly depends on the quality of lawmaking, including its ideological content and scientific elaboration. Based on the works of reputable lawyers of the past and present, the author convincingly proves that the technique of legislative activity determines the effectiveness of the adopted normative legal acts, the totality of which forms a positive law. Guided by the considerations expressed in the article, the author formulates a number of recommendations aimed at improving the legal, technical and substantive aspects of positive law in order to increase the efficiency of legal regulation

Modern Trends in Long-Term Dynamics of the Acute Intestinal Infectios Incidence of Bacterial and Viral Etiology

Relevance. According to the scientific literature in the Russian Federation (RF), over recent years there has been a decrease in the incidence of acute bacterial intestinal infections (AII) and, conversely, an increase in the incidence of AII of viral etiology. The reasons for these trends remain unclear in many respects. Goal. To study the trends in the long-term dynamics of the incidence of AII of bacterial and viral etiology among the population of the RF. Materials and methods. The work uses the materials of state reports of the Federal Service for Supervision of Consumer Rights Protection and Human Well-Being for 2000 - 2018. The incidence rates of bacterial AII (dysentery, salmonellosis, intestinal yersiniosis, Escherichiosis and intestinal infections caused by opportunistic bacteria) and viral AII (rota-, noro-, enterovirus infections), as well as the results of microbiological control of food and drinking water were studied compliance with sanitary regulations. Results. A tendency towards an increase in the incidence of acute intestinal infections with an average annual rate of 1,7% in population of the Russian Federation was revealed. At the same time, there was a decrease in the incidence of bacterial AII with an average annual rate of 3,8% and, conversely, an increase in the incidence of viral AII with an average annual rate of 384,1%. These changes were observed on the back of a decrease of samples` percent of food and drinking water that did not meet sanitary standards for bacteriological indicators, and an expansion of the range of virological methods for diagnosing viral AII. Conclusion. During 2000–2018 revealed a decrease in the incidence of bacterial OCI in the Russian Federation against the background of improved quality of food and drinking water according to microbiological indicators and, on the contrary, a sharp increase in the incidence of viral OCI associated with the expansion of the spectrum and scope of diagnostic virological studies

Frequency and Risk Factors of Purulent Septic Infection among Adults after Different Types of an Open Heart Operations

Relevance. The problem of purulent postoperative septic infection (the hospital acquired infection or HAI) is still one of the main cause of fatal outcomes of patients in cardiac hospitals, which demands significant material costs. The aim of the work is to evaluate the intensity of the epidemic process and risk factors for HAI among adults after various types of open heart surgery.Materials and methods. The study of medical records of 1540 patients over 18 years old, who underwent open heart surgery for the purpose of coronary artery bypass grafting (CABG), prosthetics of valves and elimination of aortic defects, was held. Typical and donozological forms of HAI were taken into account in accordance with the epidemiological standard definition of cases.Results. The incidence rates of typical and donozological forms of HAI in average was 39.6 and 72.7 per 1000 operations. The maximum incidence of HAI was detected after aortic surgery due to urinary tract infection (UTI) and hospital-acquired pneumonia.Conclusions. It was found that the increased incidence of UTI and hospital-acquired pneumonia after aortic surgery is contingent on a longer cardiosurgical operations and, accordingly, a longer stay of patients in the Department of anesthesia and resuscitation, accompanied by artificial ventilation and catheterization of the bladder, than in other cardiac operation

Detection of tuberculous mycobacteria in sputum and intensity of bacillary excretion in tuberculosis patients with various HIV status

Goal of the study: to investigate the informativeness of tuberculous mycobacteria detection by various techniques and to analyze the intensity of bacillary excretion in tuberculosis patients depending on their HIV status. Materials and methods. 360 HIV patients were examined due to suspected tuberculosis. The diagnostic procedure included two consecutive sputum test for acid fast bacilli (AFB)/tuberculous mycobacteria by fluorescent microscopy, molecular genetic tests and culture on liquid and solid media. Tuberculosis was diagnosed in 178 (49.4%) patients. The comparison group included 354 tuberculosis patients with negative HIV status including 113 patients who underwent the same diagnostic procedure as those suffering from TB/HIV co-infection. results of the study. AFB were more often detected by fluorescent microscopy in HIV negative tuberculosis patients compared to those with TB/HIV co-infection (32.8 and 24.2% respectively), and the sensitivity of the other testing methods did not differ. Scarce bacillary excretion was confidently more often registered in those suffering from TB/HIV co-infection and less frequently they had massive bacillary excretion detected by culture on solid media compared to HIV negative tuberculosis patients. The complete diagnostic procedure demonstrated better sensitivity in those with TB/HIV co-infection compared to tuberculosis patients with negative HIV status (87.1 and 71.2%). © 2018 New Terra Publishing House. All Rights Reserved