Foreign body granuloma as a complication of cosmetological procedures

The aim of the study – to demonstrate a clinical case of granulomas formation after introduction of a hyaluronic acid preparation.Цель исследования – демонстрация клинического случая формирования гранулематозной реакции после введения препарата гиалуроновой кислоты

Annual Sedimentary Record From Lake Donguz-Orun (Central Caucasus) Constrained by High Resolution SR-XRF Analysis and Its Potential for Climate Reconstructions

Bottom sediments of the proglacial Lake Donguz-Orun situated at ∼2500 m a.s.l. in the Elbrus Region (Central Caucasus) reveal regular laminae, characteristic of proglacial varved lakes. This is the first laminated sediment sequence recorded in the region. However, visual counting of the layers was restricted due to partial indistinctness of the lamination. In order to confirm the annual sedimentary cyclicity and proceed with annually resolved data, in addition to the visual identification we used high-resolution geochemical markers. The upper 160 mm of the sediment core were scanned at 200 μm intervals using synchrotron radiation X-ray fluorescence analysis (SR-XRF). Additional ultrahigh resolution scanning at 30 μm increments was employed for the upper 20 mm of the core. The Rb/Sr and Zr/Rb ratios are interpreted to record annual changes in grain-size. Based on this geochemical assessment, we identified 88 annual layers covering the interval between 1922 and 2010, while visually we have been able to identify between 70 and 100 layers. The correctness of the geochemical results is confirmed by mean accumulation rates assessed by 137Cs and 210Pb dating. Cross-correlation between the ring width of local pine chronology and the layer thickness, identified as a distance between the annual Rb/Sr peaks, allowed for the accurate dating of the uppermost preserved year of the sediment sequence (AD 2010). Annually averaged elemental data were then compared with regional meteorological observations, glacier mass balance and tree-ring chronologies. The comparison revealed notable conformities: content of bromine is positively correlated with annual temperatures (r = 0.41, p < 0.01), content of terrigenous elements (major elements with the origin in watershed rocks) is positively correlated (up to r = 0.44, p < 0.01) with annual precipitation. A high statistically significant negative relationship is observed between the concentrations of terrigenous elements and tree-ring width of local pine chronology (up to r = -0.56, p < 0.01). Taken together, these data point to a common composite climatic signal in the two independent records (lake sediments and tree rings) and confirm that the laminae represent annual layers (i.e., varves). These findings open opportunities for high-resolution multiproxy climate reconstructions 300–350 years long using the longer sediment core and tree-ring records

Абсолютный и относительный возраст морен стадий Актру и Историческая ледников Центрального Алтая по данным лихенометрии и дендрохронологии

Dendrochronology, and lichenometry were used to determine the relative and absolute age of the Late Holocene moraines of the glaciers of the Aktru, Maashei and Shavla valleys (North Chuya ridge, Central Altai). An array of 86dendrochronological dates, related to moraine deposits, is analyzed, 30 of which are published for the first time. Also, for the first time, data on the relative (lichenometric) age of the young deposits of the Aktru Valley, and data on the lichenometry of the moraines of the Maashey glacier and one of the glaciers of the Shavly valley were obtained. We used the capabilities of each method and the expediency of their combined use in the study area. It was confirmed that the growth rates of lichens on the moraines of the Aktru stage (XVIII–XIX centuries) are generally consistent with the previously published estimates. The moraines of the Historical stage, which date earlier than 1700–2300 years ago, supports the lichens as large as 120–160 mm, but the scattering of their diameters is too large and the assessment of the lichenometric ages of these moraines seems to be problematic, but not completely excluded. The Akkem stage of glacier advance according to the recent publications dates back to the Late Glacial or Early Holocene time; the lichenometry is obviously not applicably at such ancient surfaces. According to dendrochronological dating, the glaciers of the North Chuisky Ridge in the last millennium advanced at least twice up to their maximum extent in the XVII– early XIX and XII centuries. In the 8th century, the sizes of the glaciers possibly, approached modern ones. Aſter the XVII century, the cedar (Pinus Sibirica) in Central Altai significantly reduced its distribution area due to the climate cooling, retreating from the periglacial territories, where it was distributed earlier. All trees that grew near the glaciers, above 2300 m, died. The comparison of the dates of glacier advances in the past millennia with the tree-ring, ice-core, and palynological reconstructions of summer temperature and precipitation show a good correspondence.Методы дендрохронологии и лихенометрии применены для определения относительного и абсолютного возраста позднеголоценовых морен ледников Центрального Алтая (Северо-Чуйский хребет). Установлено, что скорости роста лишайников– индикаторов на моренах стадии Актру– в целом согласуются с опубликованными ранее оценками. По данным дендрохронологического датирования, ледники этого района в последнем тысячелетии имели два максимума наступания: в XII в. и в XVII– начале XIX вв. (максимум продвижения). В VIII в. площадь ледников приближалась к современной. Размеры лишайников подрода Rizocarpon на моренах стадии Актру варьируют от 20 до 41 мм, на моренах Исторической стадии– от 120 до 160 мм, что в спорных случаях позволяет однозначно идентифицировать морену

Изменения ледника Чалаати (Грузинский Кавказ) с малого ледникового периода по данным космогенных изотопов (10Be) и дендрохронологии

Glacier variations over the past centuries are still poorly documented on the southern slope of the Greater Caucasus. In this paper, the change of Chalaati Glacier in the Georgian Caucasus from its maximum extent during the Little Ice Age has been studied. For the first time in the history of glaciological studies of the Georgian Caucasus, 10Be in situ Cosmic Ray Exposure (CRE) dating was applied. The age of moraines was determined by tree-ring analysis. Lichenometry was also used as a supplementary tool to determine the relative ages of glacial landforms. In addition, the large-scale topographical maps (1887, 1960) were used along with the satellite imagery – Corona, Landsat 5 TM, and Sentinel 2B. Repeated photographs were used to identify the glacier extent in the late XIX and early XX centuries. 10Be CRE ages from the oldest lateral moraine of the Chalaati Glacier suggest that the onset of the Little Ice Age occurred ~0.73±0.04 kyr ago (CE ~1250–1330), while the dendrochronology and lichenometry measurements show that the Chalaati Glacier reached its secondary maximum extent again about CE ~1810. From that time through 2018 the glacier area decreased from 14.9±1.5 km2 to 9.9±0.5 km2 (33.8±7.4% or ~0.16% yr−1), while its length retreated by ~2280 m. The retreat rate was uneven: it peaked between 1940 and 1971 (~22.9 m yr−1), while the rate was slowest in 1910– 1930 (~4.0 m yr−1). The terminus elevation rose from ~1620 m to ~1980 m above sea level in ~1810–2018.Для реконструкции колебаний ледника Чалаати в Грузии использовались космические снимки, старые карты, повторные фотографии, дендрохронология, лихенометрия и анализ космогенных изотопов. Максимальное наступание ледника в начале малого ледникового периода произошло в ~1250–1330 гг., второй максимум, когда ледник достиг почти такой же длины, датируется примерно 1810 г. С этого времени до 2018 г. площадь ледника уменьшилась с 14,9±1,5 до 9,9±0,5 км2 (33,8±7,4%, или ~0,16% год−1), а его длина сократилась на ~2280 м

Реконструкция баланса массы ледника Гарабаши (1800–2005 гг.) по дендрохронологическим данным

The exploration whether tree-ring data can be effectually applied for the mass balance reconstruction in Caucasus was the main goal of this research. Tree-ring width and maximum density chronologies of pine (Pinus sylvestris L.) at seven high-elevation sites in Northern Caucasus were explored for this purpose. As well as in other places of the temperate zone tree- ring width has complex climate signal controlled both temperature and precipitation. Instrumental mass balance records of Garabashi Gglacier started at 1983s. It is well known that Caucasus glaciers intensively retreat in the last decades and according to instrumental data mass balance variations are mostly controlled by the ablation, i.e. summer temperature variations. Maximum density chronology has statistically significant correlation with mass balance due to summer temperature sensitivity and great input of ablation to total mass balance variations. To include in our reconstruction different climatically sensitive parameters, stepwise multiple regression model was used. The strongest relation (r = 0.88; r2 = 0.78; p < 0.05) between two ring-width and one maximum density chronologies was identified. Cross-validation test (r = 0.79; r2 = 0.62; p < 0.05) confirmed model adequacy and it allowed to reconstruct Garabashi Glacier mass balance for 1800–2005ss. Reconstructed and instrumental mass balance values coincide well except the most recent period in 2000s, when the reconstructed mass balance slightly underestimated the real values. However even in this period it remained negative as well as the instrumental records. The bias can be explained by the weak sensitivity of the chronologies to winter precipitation (i.e. accumulation). The tree-ring based mass balance reconstruction was compared with one based on meteorological data (since 1905s). Both reconstructions have good interannual agreement (r = 0.53; p < 0.05) particularly for the period between 1975 and 2005. According to the reconstruction two distinct periods of positive mass balance occurred in 1830s and 1860s. They agree well with early historical data and the tree-ring of moraines of Kashkatash Glacier in Central Caucasus. Выполнена первая реконструкции баланса массы ледника Гарабаши по дендрохронологическим данным с 1800 по 2005 г. Лучше всего модель воспроизводит изменчивость годового баланса ледника при использовании хронологий по ширине годичных колец и по максимальной плотности поздней древесины. Изучен вклад каждой древесно-кольцевой хронологии в модель и её климатический отклик. Установлена высокая согласованность реконструкции баланса массы ледника по дендрохронологическим данным с реконструкциями, полученными ранее по метеорологическим рядам

Оценка перспективы использования модели гестационного сахарного диабета для поиска средств фармакологической коррекции нарушений у потомства крыс

Imbalance of glucose homeostasis in the mother-placenta-fetus system in case of gestational diabetes mellitus (GDM) leads to pre- and postnatal abnormalities in offspring. Lack of universally recognized GDM-model complicates the search for pathogenetic means to prevent and correct abnormalities in offspring. A model using food load (high-calorie diet) in combination with low doses of diabetogen streptozotocin (HCD-STZ model) seems to be one of the closest in causes, mechanisms of development and clinical findings. Hence, the aim was to work out and assess the suitability of HCD-STZ model of GDM in order to register abnormalities in the offspring and determine the possibility of their pharmacological correction. Rats and its fetuses were the objects of the study. Modeling of GDM involved keeping rats on a high-calorie diet (NCD) for at least 10 weeks followed by a single injection of low-dose STZ on the first day of gestation. The hyperglycemia characteristic of GDM is recorded in less than 40 % of animals in HCD group combined with streptozotocin at a dose of 25 mg/kg. This fact does not allow a reliable assessment of abnormalities of antenatal and postnatal development of offspring. Thus, the model used is not promising for finding means of pharmacological correction of the effect of GDM on offspring.Нарушение гомеостаза глюкозы в системе «мать–плацента–плод» при гестационном сахарном диабете (ГСД) ведёт к пре- и постнатальным отклонениям у потомства. Отсутствие общепризнанной модели ГСД осложняет поиск патогенетических средств предупреждения и коррекции отклонений у потомства. Одной из наиболее близких по причинам возникновения, механизмам развития и клинической картине представляется модель с использованием пищевой нагрузки (высококалорийной диеты) в комбинации с низкими дозами диабетогена стрептозотоцина (ВКД-СТЗ-модель). Отсюда возникла задача по отработке и оценке пригодности ВКД-СТЗ-модели ГСД с целью регистрации отклонений у потомства и последующим определением возможности их фармакологической коррекции. Объектом исследования служили крысы и плоды крыс. Моделирование ГСД предусматривало содержание крыс на высококалорийной диете (ВКД) в течение не менее 10 недель с последующим однократным введением низких доз стрептозотоцина (СТЗ) в первый день беременности. При ВКД в сочетании с СТЗ в дозе 25 мг/кг гипергликемия, характерная для ГСД, регистрируется менее чем у 40 % животных, что в дальнейшем не позволяет достоверно оценить нарушения антенатального и постнатального развития у потомства. Таким образом, использованная модель не перспективна для поиска средств фармакологической коррекции влияния ГСД на потомство

Динамика нивально-гляциальных склоновых процессов в бассейнах рек Баксан и Теберда по данным радиоуглеродного датирования погребённых почв

Radiocarbon and tree-ring dating of the soil horizons, buried in the slope and fluvioglacial deposits in Baksan and Teberda valleys, bring evidence of the reduction of the avalanche activity, stabilization of the slopes and soil formation on their surfaces. In the Baksan section three such horizons are identified, while in the Teberda section only one. The radiocarbon dates of the two thickest soil horizons in the Baksan section are 170±50 BP (1650–1890 CE) and 380±60 BP (1430–1650 CE). The dendrochronological date of the wood (after 1677) in the upper layer of the buried soil horizon in the in the Dombai section probably indicate the increase of the river runoff and debris flow activity in relation with the glacier advance in the upperstream of Ammanauz river. However it is also close to the Terskoye earth quake occurred in 1688. The radiocarbon dates of the buried soils cluster in three groups (270–290, 340–440, 1280–1440 yrs BP). It is possible that their burial is connected to the climatic (increase in precipitation, especially extreme ones) or seismic causes.В разрезе склоновых отложений р. Баксан и флювиогляциальных отложений р. Аманауз (пос. Домбай) радиоуглеродным и дендрохронологическим методами датированы горизонты погребённых почв. В разрезе «Баксан» выделяются три таких горизонта, в разрезе «Домбай» – один. Радиоуглеродный возраст двух наиболее выраженных горизонтов погребённых почв в верховьях долины р. Баксан составляет 170±50 л.н. (1650–1890 гг.) и 380±60 л.н. (1430–1650 гг.). Гибель дерева (дендрохронологическая датировка – после 1677 г.), захороненного в кровле погребённого почвенного горизонта в разрезе «Домбай», возможно, указывает на увеличение в это время объёма речного стока и селевой активности в связи с изменениями размеров ледников в верховьях р. Аманауз, однако не исключено и совпадение с Терским землетрясением 1688 г. Датировки погребённых почв в регионе объединяются в три группы: 270–290, 340–440 и 1280–1440 л.н. Возможны климатические (увеличение осадков, в том числе экстремальных) или сейсмические причины захоронения этих почвенных горизонтов

Arctic hydroclimate variability during the last 2000 years : current understanding and research challenges

Reanalysis data show an increasing trend in Arctic precipitation over the 20th century, but changes are not homogenous across seasons or space. The observed hydro-climate changes are expected to continue and possibly accelerate in the coming century, not only affecting pan-Arctic natural ecosystems and human activities, but also lower latitudes through the atmospheric and ocean circulations. However, a lack of spatiotemporal observational data makes reliable quantification of Arctic hydroclimate change difficult, especially in a long-term context. To understand Arctic hydroclimate and its variability prior to the instrumental record, climate proxy records are needed. The purpose of this review is to summarise the current understanding of Arctic hydroclimate during the past 2000 years. First, the paper reviews the main natural archives and proxies used to infer past hydroclimate variations in this remote region and outlines the difficulty of disentangling the moisture from the temperature signal in these records. Second, a comparison of two sets of hydroclimate records covering the Common Era from two data-rich regions, North America and Fennoscandia, reveals inter- and intra-regional differences. Third, building on earlier work, this paper shows the potential for providing a high-resolution hydroclimate reconstruction for the Arctic and a comparison with last-millennium simulations from fully coupled climate models. In general, hydroclimate proxies and simulations indicate that the Medieval Climate Anomaly tends to have been wetter than the Little Ice Age (LIA), but there are large regional differences. However, the regional coverage of the proxy data is inadequate, with distinct data gaps in most of Eurasia and parts of North America, making robust assessments for the whole Arctic impossible at present. To fully assess pan-Arctic hydroclimate variability for the last 2 millennia, additional proxy records are required.Peer reviewe

Potential climatic transitions with profound impact on Europe

We discuss potential transitions of six climatic subsystems with large-scale impact on Europe, sometimes denoted as tipping elements. These are the ice sheets on Greenland and West Antarctica, the Atlantic thermohaline circulation, Arctic sea ice, Alpine glaciers and northern hemisphere stratospheric ozone. Each system is represented by co-authors actively publishing in the corresponding field. For each subsystem we summarize the mechanism of a potential transition in a warmer climate along with its impact on Europe and assess the likelihood for such a transition based on published scientific literature. As a summary, the ‘tipping’ potential for each system is provided as a function of global mean temperature increase which required some subjective interpretation of scientific facts by the authors and should be considered as a snapshot of our current understanding. <br/

Бурение осадков оз. Каракель (долина р. Теберда) и перспективы реконструкции истории оледенения и климата голоцена на Кавказе

Lacustrine sediments represent an important data source for glacial and palaeoclimatic reconstructions. Having a number of certain advantages, they can be successfully used as a means of specification of glacier situation and age of moraine deposits, as well as a basis for detailed climatic models of the Holocene. The article focuses on the coring of sediments of Lake Kakakel (Western Caucasus) that has its goal to clarify the Holocene climatic history for the region, providing the sampling methods, lithologic description of the sediment core, obtained radiocarbon dating and the element composition of the sediments. The primary outlook over the results of coring of the sediments of the Lake Karakyol helped to reconsider the conventional opinion on the glacial fluctuations in the valley of Teberda and to assume the future possibility for high-definition palaeoclimatic reconstruction for Western Caucasus.Озёрные отложения – важный источник данных для реконструкции колебаний ледников и изменений климата. Рассмотрены первые результаты бурения осадков оз. Каракель (долина р. Теберда, Западный Кавказ), выполненного для реконструкции голоценовой истории оледенения и климата в регионе. Описаны методика отбора образцов и особенности стратиграфии керна донных отложений оз. Каракель, приведены три радиоуглеродные датировки, позволившие оценить скорости осадконакопления в верхней части толщи (поздний голоцен). Датировка нижнего слоя озёрных отложений – 11 700 л.н. (календарный возраст) – одновременно представляет собой оценку минимального возраста морены, подпруживающей оз. Каракель