Dependence of pH values in the digestive tract of freshwater fishes on some abiotic and biotic factors

The values of pH in the digestive tracts of 20 freshwater fish species inhabiting various Russian Federation waterbodies were studied. Only in six species (Coregonus lavaretus, Coregonus migratorius, Catostomus catostomus, Carassius gibelio, Rutilus rutilus, Leuciscus leuciscus) out of 20 species, the differences in pH values between different regions of the intestine were significant. Feeding habits, feeding frequency, and gut fullness in fish affected pH values. Temperature was one of the most important factors affecting pH values. During cold seasons (spring and fall; average water temperature: 8–10 and 5–6○C, respectively), the pH values in fish guts were higher than that in the summer seasons(water temperature 22–25°C) for C. gibelio, Perca fluviatilis, Cyprinus carpio, L. leuciscus, and R. rutilus from the Chany Lake. Similar results (lower pH values in intestine at higher water temperatures) were also obtained for C. gibelio in warmer years in comparison to colder years in the same waterbody and in L. leuciscus and P. fluviatilis in the different waterbodies with different water temperatures. It is hypothesized that dependence of pH in fish gut on temperature may serve as a regulatory mechanism for maintaining the activities of hydrolytic enzymes at the required level for their successful functioning.info:eu-repo/semantics/acceptedVersio

Эпидемиология генерализованной менингококковой инфекции в Новосибирской области (1992–2015 гг.)

Aim: To study the epidemiological patterns of invasive meningococcal disease in Novosibirsk region within a time period from 1992 to 2015.Methods: retrospective comparative epidemiological analysis.Results: During the analyzed period the annual incidence rate of invasive meningococcal disease was higher than average annual incidence rate in Russian Federation. Totally1690 cases were registered, average incidence rate for the period 2000–2015 was 2,2/100,000 exceeding the neighbor regions. The incidence had a tendency to continually decline and is characterized by the cyclical fluctuations with period of 4-7 years. Majority of cases occurred in children < 14 years, varying from 77,3% in 2001 to 57,8% in 2008. The highest incidence was registered in children <12 month reaching 124/100,000 of population in 2003. The increase of mortality correlated with the decrease of incidence, average mortality for period 1992–2015 was 11,4%. In etiologic structure serogroup B is predominant – 40,9%, serogrup A – 20,6%, serogrup C – 14,7%. The distinctiveness of epidemiology is cyclic dynamics with the periods of predominance of serogroup A (up to 48% in 2014). In serum analysis performed 2012 45% of probes were positive for serogroup A what demonstrates circulation of this serogoup among population.Conclusion: High incidence among children <14 years and especially among children <12 month in emerging risk of the forthcoming rise in incidence of meningococcal disease and insufficient surveillance provide need in activation of tactics of specific immuneprophylactics. Цель: изучение эпидемиологических закономерностей генерализованной менингококковой инфекции в Новосибирской области за 1992–2015 гг.Материалы и методы: ретроспективный сравнительный эпидемиологический анализ.Результаты: за анализируемый период показатели заболеваемости ГФМИ стабильно превышали показатели по Российской Федерации. Всего было зарегистрировано 1690 случаев заболевания, средний многолетний показатель за 2000–2015 гг. составил 2,2, что выше показателей пограничных регионов. Заболеваемость имеет поступательную тенденцию к снижению и характеризуется циклическими колебаниями с периодами в 4–7 лет. Доля детей до 14 лет колебалась от 77,3% в 2001 г. до 57,8% в 2008 г. Наиболее высокие показатели заболеваемости были зарегистрированы среди детей первого года жизни, до 124 на 100 тыс. населения в 2003 г. Рост летальности коррелировал со снижением заболеваемости, летальность за 1992–2015 гг. составила 11,4%. В этиологической структуре преобладали менингококки серогруппы В – 40,9%; серогруппа А – 20,6%; серогруппа С – 14,7%. Отличительной особенностью является циклическая динамика серотипового пейзажа с периодическим преобладанием менингококков группы А (до 48% в 2014 г). Анализ сывороток, проведенный в 2012 г., выявил 45% положительных проб к менингококку группы А, что свидетельствует о циркуляции этой группы среди населения.Заключение: высокие показатели заболеваемости детей до 14 лет и, прежде всего, детей первых 2 лет жизни в условиях риска предстоящего подъема заболеваемости МИ и недостаточного мониторирования эпидемиологической ситуации диктуют необходимость активации тактики специфической иммунопрофилактики

НОРОВИРУСНАЯ ИНФЕКЦИЯ (ОБЗОР ЛИТЕРАТУРЫ)

The share of norovirus infection is 17–20% of all cases of acute gastroenteritis in the world. The dominant II genogroup of noroviruses is characterized by rapid variability. The new recombinant norovirus GII.P16-GII.2 caused a sharp increase in the incidence of gastroenteritis in Asian and European countries during the winter season 2016–2017. The epidemiological features of norovirus infection are long-term excretion of the pathogen from the body of patients and carriers of viruses, especially in persons with immunosuppression; the implementation of various transmission routes (food, water, contact, aerosol), high contagiosity, winter seasonality in the countries of the northern hemisphere. In recent years, two human systems for the cultivation of noroviruses in vitro have been created, a double tropism of noroviruses has been established for immune cells and epithelial cells of the intestine, and the life cycle of noroviruses has been studied. The microbiota and its members can be either protective or stimulating for norovirus infection. Lactobacillus may play a protective role against norovirus infection. The existence of chronic norovirus infection lasting from several months to several years is proved, especially in patients with immunodeficiency. Severe form of norovirus infection and deaths are more often recorded in young children, the elderly, patients with comorbidity and immunocompromised individuals. The clinical picture of norovirus gastroenteritis is similar in many respects to other viral gastroenteritis, which determines the need for laboratory verification of the diagnosis. The polymerase chain reaction method with reverse transcription is the most widely used in the world for diagnosing infection in patients and for detecting the virus in food and environmental objects. There are still no approved vaccines and antiviral drugs against this infection. Recommended therapeutic interventions include, along with rehydration with hypoosmolar solutions, the administration of specific probiotics such as Lactobacillus GG or Saccharomyces boulardii, diosmectit and racecadotril.Доля норовирусной инфекции составляет 17–20% всех случаев острого гастроэнтерита в мире. Доминирующая II геногруппа норовирусов характеризуется быстрой изменчивостью. Новый рекомбинантный норовирус GII.P16-GII.2 вызвал резкий рост случаев гастроэнтерита в странах Азии и Европы в зимний сезон 2016–2017 гг. Эпидемиологическими особенностями норовирусной инфекции являются длительное выделение возбудителя из организма больных и вирусовыделителей, особенно у лиц с иммуносупрессией, реализация различных путей передачи (пищевого, водного, контактно-бытового, аэрозольного), высокая контагиозность, зимняя сезонность в странах северного полушария. В последние годы созданы две человеческие системы для культивирования норовирусов in vitro, установлен двойной тропизм норовирусов к иммунным клеткам и эпителиальным клеткам кишечника, изучается жизненный цикл норовирусов. Микробиота и ее члены могут быть либо протективными, либо стимулирующими для норовирусной инфекции. Lactobacillus могут играть защитную роль против норовирусной инфекции. Доказано существование хронической норовирусной инфекции длительностью от нескольких месяцев до нескольких лет, особенно у пациентов с иммунодефицитом. Тяжелая форма норовирусной инфекции и летальные исходы чаще регистрируются у детей младшего возраста, пожилых, пациентов с коморбидностью и иммунокомпроментированных лиц. Клиническая картина норовирусного гастроэнтерита во многом сходна с другими вирусными гастроэнтеритами, что определяет необходимость лабораторной верификации диагноза. Метод полимеразной цепной реакции с обратной транскрипцией получил наибольшее распространение в мире для диагностики инфекции у пациентов и для обнаружения вируса в пищевых продуктах и объектах окружающей среды. До сих пор нет одобренных вакцин и антивирусных препаратов против этой инфекции. Рекомендуемые терапевтические вмешательства, наряду с регидратацией гипоосмолярными растворами, включают назначение специфических пробиотиков, таких как Lactobacillus GG или Saccharomyces boulardii, диосмектит и рацекадотрил.

Observations of Non-radial Pulsations in Radio Pulsars

We introduce a model for pulsars in which non-radial oscillations of high spherical degree (l) aligned to the magnetic axis of a spinning neutron star reproduce the morphological features of pulsar beams. In our model, rotation of the pulsar carries a pattern of pulsation nodes underneath our sightline, reproducing the longitude stationary structure seen in average pulse profiles, while the associated time-like oscillations reproduce "drifting subpulses"--features that change their longitude between successive pulsar spins. We will show that the presence of nodal lines can account for observed 180 degree phase jumps in drifting subpulses and their otherwise poor phase stability, even if the time-like oscillations are strictly periodic. Our model can also account for the "mode changes" and "nulls" observed in some pulsars as quasiperiodic changes between pulsation modes of different l or radial overtone n, analogous to pulsation mode changes observed in oscillating white dwarf stars. We will discuss other definitive and testable requirements of our model and show that they are qualitatively supported by existing data. While reserving judgment until the completion of quantitative tests, we are inspired enough by the existing observational support for our model to speculate about the excitation mechanism of the non-radial pulsations, the physics we can learn from them, and their relationship to the period evolution of pulsars.Comment: 28 pages, 9 figures (as separate png files), Astrophysical Journal, in pres

Менингококковая инфекция у детей в период 2012–2021 гг. Основные итоги ретроспективного многоцентрового исследования, проблемы сегодняшнего дня

The heavy burden of meningococcal infection is associated not only with life-threatening complications in the acute period and high mortality in invasive forms of the disease, but also with severe consequences in survivors, who are not recorded in our country.The aim of study: to analyze clinical manifestations, complications of the acute period and outcomes of invasive forms of meningococcal disease in children in various regions of the Russian Federation.Materials and methods: an analysis of data from 1327 inpatient medical records of children with an invasive meningococcal infection from 14 regional centers of the Russian Federation for 2012-2021 was carried out (28.3% of cases of the disease in children in the represented federal districts).Results: it was found that young children predominated among the patients – the median was 27.4 (10.7-70.4) months. Complications of the acute period, often combined, were observed in 47.6% of cases. The development of septic shock was noted in 30.4%, Waterhouse-Friderichsen syndrome in 6.6%, carditis in 2.9%, cerebral edema in 15.7%, arthritis in 1.4% of cases; the formation of hydrocephalus, subdural effusion, sensorineural hearing loss in 1.8%, 0.6%, 1% of children, respectively. The presence of soft tissue necrosis requiring surgical intervention was noted in 3.5% of cases. Mortality rate was 10.1%. At the time of discharge from the hospital, 30% of children had complications associated with meningococcal infection: organ dysfunction/ failure in 13.2% of patients (severe in 1.3%), cerebral insufficiency in 19.6%; severe psycho-neurological deficits, sensorineural hearing loss, problems associated with the need for orthopedic/surgical interventions accounted for 0.7%, 0.6% and 0.8%, respectively.Conclusion. Considering the epidemiological features of meningococcal infection – the risk of a sharp increase in morbidity in short periods of time, the life-threatening nature of the disease itself, it is necessary to remain alert to these risks and take all possible measures to prevent the disease using all available means, the most effective of which is vaccine prevention.Тяжелое бремя менингококковой инфекции связано не только с жизнеугрожающими осложнениями острого периода и высокой летальностью при генерализованных формах заболевания, но и с тяжелыми последствиями у выживших, учет которых в нашей стране не ведется.Цель: проведение анализа клинических проявлений, осложнений острого периода и исходов генерализованных форм менингококковой инфекции у детей в различных регионах Российской Федерации.Материалы и методы: проведен анализ данных 1327 медицинских карт (форма 003/у) детей с генерализованной формой менингококковой инфекции из 14 региональных центров Российской Федерации за 2012– 2021 гг. (28,3% случаев заболевания у детей в представляемых федеральных округах).Результаты: установлено, что среди больных преобладали дети раннего возраста – медиана составила 27,4 (10,7–70,4) месяцев. Осложнения, часто сочетанные, в остром периоде заболевания наблюдались в 47,6% случаев: септический шок в 30,4%, синдром Уотерхауза – Фридериксена в 6,6%, кардит в 2,9%, отек головного мозга в 15,7%, артриты в 1,4%, гидроцефалия в 1,8%, сенсоневральная тугоухость в 1%, субдуральный выпот в 0,6% случаев. Наличие некрозов мягких тканей, требовавших хирургического вмешательства, отмечено в 3,5% случаев. Летальность составила 10,1%. На момент выписки из стационара у 30% детей выявлялись осложнения, в том числе выраженная органная дисфункция в 1,3%, грубый психоневрологический дефицит, сенсоневральная тугоухость; осложнения, требующие проведения ортопедических/хирургических вмешательств, составили 0,7%, 0,6% и 0,8% соответственно.Анализ полученных данных позволил вскрыть существующие проблемы, касающиеся клинической и этиологической диагностики заболевания, возможностей выявления осложнений острого периода и учета последствий генерализованных форм менингококковой инфекции.Заключение. Учитывая эпидемиологические особенности менингококковой инфекции (риск резкого подъема заболеваемости в короткие временные промежутки, жизнеугрожающий характер самого заболевания), необходимо сохранять настороженность в отношении данных рисков и предпринимать все возможные меры для профилактики заболевания с использованием всех доступных средств, наиболее эффективным из которых является вакцинопрофилактика

Epidemiology of invasive meningococcal disease in Novosibirsk region during 1992–2015

Aim: To study the epidemiological patterns of invasive meningococcal disease in Novosibirsk region within a time period from 1992 to 2015.Methods: retrospective comparative epidemiological analysis.Results: During the analyzed period the annual incidence rate of invasive meningococcal disease was higher than average annual incidence rate in Russian Federation. Totally1690 cases were registered, average incidence rate for the period 2000–2015 was 2,2/100,000 exceeding the neighbor regions. The incidence had a tendency to continually decline and is characterized by the cyclical fluctuations with period of 4-7 years. Majority of cases occurred in children < 14 years, varying from 77,3% in 2001 to 57,8% in 2008. The highest incidence was registered in children <12 month reaching 124/100,000 of population in 2003. The increase of mortality correlated with the decrease of incidence, average mortality for period 1992–2015 was 11,4%. In etiologic structure serogroup B is predominant – 40,9%, serogrup A – 20,6%, serogrup C – 14,7%. The distinctiveness of epidemiology is cyclic dynamics with the periods of predominance of serogroup A (up to 48% in 2014). In serum analysis performed 2012 45% of probes were positive for serogroup A what demonstrates circulation of this serogoup among population.Conclusion: High incidence among children <14 years and especially among children <12 month in emerging risk of the forthcoming rise in incidence of meningococcal disease and insufficient surveillance provide need in activation of tactics of specific immuneprophylactics

NOROVIRUS INFECTION (SYSTEMATIC REVIEW)

The share of norovirus infection is 17–20% of all cases of acute gastroenteritis in the world. The dominant II genogroup of noroviruses is characterized by rapid variability. The new recombinant norovirus GII.P16-GII.2 caused a sharp increase in the incidence of gastroenteritis in Asian and European countries during the winter season 2016–2017. The epidemiological features of norovirus infection are long-term excretion of the pathogen from the body of patients and carriers of viruses, especially in persons with immunosuppression; the implementation of various transmission routes (food, water, contact, aerosol), high contagiosity, winter seasonality in the countries of the northern hemisphere. In recent years, two human systems for the cultivation of noroviruses in vitro have been created, a double tropism of noroviruses has been established for immune cells and epithelial cells of the intestine, and the life cycle of noroviruses has been studied. The microbiota and its members can be either protective or stimulating for norovirus infection. Lactobacillus may play a protective role against norovirus infection. The existence of chronic norovirus infection lasting from several months to several years is proved, especially in patients with immunodeficiency. Severe form of norovirus infection and deaths are more often recorded in young children, the elderly, patients with comorbidity and immunocompromised individuals. The clinical picture of norovirus gastroenteritis is similar in many respects to other viral gastroenteritis, which determines the need for laboratory verification of the diagnosis. The polymerase chain reaction method with reverse transcription is the most widely used in the world for diagnosing infection in patients and for detecting the virus in food and environmental objects. There are still no approved vaccines and antiviral drugs against this infection. Recommended therapeutic interventions include, along with rehydration with hypoosmolar solutions, the administration of specific probiotics such as Lactobacillus GG or Saccharomyces boulardii, diosmectit and racecadotril