Reconstructions of deltaic environments from Holocene palynological records in the Volga delta, northern Caspian Sea

This article was made available through open access by the Brunel Open Access Publishing Fund.New palynological and ostracod data are presented from the Holocene Volga delta, obtained from short cores and surface samples collected in the Damchik region, near Astrakhan, Russian Federation in the northern Caspian Sea. Four phases of delta deposition are recognized and constrained by accelerated mass spectrometry (AMS) radiocarbon ages. Palynological records show that erosive channels, dunes (Baer hills) and inter-dune lakes were present during the period 11,500–8900 cal. BP at the time of the Mangyshlak Caspian lowstand. The period 8900–3770 cal. BP was characterized regionally by extensive steppe vegetation, with forest present at times with warmer, more humid climates, and with halophytic and xerophytic vegetation present at times of drought. The period 3770–2080 cal. BP was a time of active delta deposition, with forest or woodland close to the delta, indicating relatively warm and humid climates and variable Caspian Sea levels. From 2080 cal. BP to the present-day, aquatic pollen is frequent in highstand intervals and herbaceous pollen and fungal hyphae frequent in lowstand intervals. Soils and incised valley sediments are associated with the regional Derbent regression and may be time-equivalent with the ‘Medieval Warm Period’. Fungal spores are an indicator of erosional or aeolian processes, whereas fungal hyphae are associated with soil formation. Freshwater algae, ostracods and dinocysts indicate mainly freshwater conditions during the Holocene with minor brackish influences. Dinocysts present include Spiniferites cruciformis, Caspidinium rugosum, Impagidinium caspienense and Pterocysta cruciformis, the latter a new record for the Caspian Sea. The Holocene Volga delta is a partial analogue for the much larger oil and gas bearing Mio-Pliocene palaeo-Volga delta.Funding for the data collection and field work was provided from the following sources: 1 – IGCP-UNESCO 2003–2008 (Project 481 CASPAGE, Dating Caspian Sea Level Change); 2 – NWO, Netherlands Science Foundation and RFFI, Russian Science Foundation 2005–2008 (Programme: ‘VHR Seismic Stratigraphy and Paleoecology of the Holocene Volga Delta’); and 3 – BP Exploration (Caspian Sea) Sea Ltd. (Azeri-Chirag-Gunashli) 2005–2008 (‘Unravelling the Small-Scale Stratigraphy and Sediment Dynamics of the Modern Volga Delta Using VHR Marine Geophysics’). The palynological work was funded jointly by BP Exploration (Caspian Sea) Ltd., Delft University of Technology and KrA Stratigraphic Ltd. Ostracod analyses were funded by StrataData Ltd. and funding for two additional radiocarbon dates provided by Deltares

From the Allerød to the mid-Holocene: Palynological evidence from the south basin of the Caspian Sea

This article has been made available through the Brunel Open Access Publishing Fund. Copyright @ The Authors. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-No Derivative Works License, which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.Pollen and dinoflagellate cysts have been analysed in a core from the south basin of the Caspian Sea, providing a picture of respectively past vegetation and water salinity for the Late Pleistocene to middle Holocene. A relatively sharp lithological change at 0.86 m depth reflects a shift from detrital silts to carbonates-rich fine silts. From this depth upwards, a Holocene chronology is built based on ten radiocarbon dates on ostracod shells and bulk carbonates. From the vegetation point of view, the Late Pleistocene deserts and steppes were partially replaced in the most sheltered areas by an open woodland with Pinus, Juniperus-Hippophae-Elaeagnus and even Alnus-Quercus-Pterocarya and Fraxinus, related to the Allerød palynozone. This was interrupted by the Younger Dryas palynozone when Artemisia reaches a maximum in a first instance followed by a very dry phase with only a slight return of Pinus and Quercus and the rare presence of Ulmus-Zelkova. From 11.5 to 8.4 cal. ka BP, an open landscape dominated by shrubs such as Ephedra and progressively increasing Quercus appeared. The final spread of diverse evergreen and deciduous trees is delayed and occurs after 8.4 cal. ka BP. It is suggested that this delay is caused by an arid climate in the Early Holocene linked to high insolation and perhaps to a lake effect. The dinocyst assemblages fluctuate between slightly brackish (Pyxidinopsis psilata and Spiniferites cruciformis, 7 psu and lower) and more brackish (Impagidinium caspienense, ∼13 psu). In the Lateglacial (Khvalynian highstand), the assemblages remained dominated by relative low salinity taxa. A late and brief increase of salinity occurred prior to 11.2 cal. ka BP associated with the Mangyshlak lowstand. It is suggested that it was caused by a brief drop in meltwater flow from both the north and the southeast (Uzboy) and a likely evaporation increase. This lowstand occurs quasi at the same time as the end of a longer lowstand in the Black Sea. The freshest waters are then inferred as having occurred between 8.4 and ≤4.4 cal. ka BP, linked to a connection with the Amu Darya and the melting glaciers on the Pamir Mountains. The Caspian Sea is a sensitive environment, easily perturbed by global climatic changes, such as the Allerød and Holocene warming, and the Lateglacial and Younger Dryas cooling, as well as by regional changes in its hydrography, such as shifts in the Eurasian meltwater and the Volga and Amu Darya inflows.Centre National de la Recherche Scientifique, Franc

Особенности артропатии при болезни Уиппла

The authors describe a case of Whipple's disease (WD) in a 56-year-old male patient followed up for 2 years. The diagnosis was established on the evidence that there was a low-density retroperitoneal or mesenteric infiltrate at computed tomography and PAS-positive macrophages in the biopsy specimens of the duodenal retrobulbar mucosa. Arthropathy had developed within 10 years before the occurrence of intestinal symptoms, subsided with their progression, and recurred after their regression. On the basis of this observation and the data available in the literature, the authors discuss the relationships of arthropathy to the abdominal manifestations of WD.Описано двухлетнее клиническое наблюдение мужчины 56 лет с болезнью Уиппла (БУ). Диагноз был установлен на основании обнаружения при компьютерной томографии расположенного за брюшиной и в брыжейке тонкой кишки инфильтрата низкой рентгеновской плотности и выявления в биоптате слизистой оболочки залуковичного отдела двенадцатиперстной кишки PAS-позитив-ных макрофагов. Артропатия развилась за 10 лет до появления кишечной симптоматики, стихла с ее развитием и возобновилась после достижения клинической ремиссии. На основании данного наблюдения и данных литературы обсуждаются взаимоотношения артропатии и абдоминальных проявлений БУ

Modern Approaches to <i>H. pylori</i> Eradication Therapy in Adults (Literature Review and Resolution of Experts Council)

Aim: to analyze current approaches to H. pylori eradication therapy in adults and present the materials of Experts Council held on December 9, 2022 in Moscow.General statements. H. pylori infection is the main etiological factor of gastritis, peptic ulcer, and gastric cancer. Eradication of H. pylori is recognized as a necessary measure to reduce the incidence of these diseases. The approaches to selecting an eradication regimen should be optimized to take into account epidemiological trends and achieve better treatment outcomes. The updated Maastricht VI Consensus Report presents the means to overcome the difficulties in selecting an approach to the treatment of H. pylori infection. However, eradication therapy remains challenging due to adverse events (primarily antibiotic-associated diarrhea), poor treatment tolerance and patient compliance. Eradication therapy can be optimized by supplementing treatment regimens with strain-specific probiotics that reduce adverse events, improve patient compliance and eradication rates, such as Saccharomyces boulardii CNCM I-745 strain with established efficacy.Conclusion. The inclusion of certain probiotics in eradication regimens improves treatment tolerance, reduces the risk of adverse events, improves patient compliance and eradication rates

Clinical significance of Helicobacter pylori infection in iron-deficiency anemia: features of comprehensive treatment approach

Aim of investigation. To study pathogenic and clinical role of Helicobacter pylori infection at irondeficiency anemia (IDA). To present the diagnostic and treatment guidelines for these patients taking into account their specific requirements. Material and methods. Overall 120 H. pylori-positive patients of different age (from 18 to 70 years), which were subdivided into two groups were studied. The main group included 70 H. pylori-positive patients with chronic iron-deficiency anemia of unknown etiology. Patients of this group have been randomized in two homogeneous subgroups (according to severity of anemia). Patients of the subgroup 1a underwent eradication therapy for 10 days (amoxicillin 1000 mg b.i.d., clarithromycin 500 mg b.i.d.; esomeprazole 20 mg b.i.d.) followed by the course of treatment by ferrous iron combined to ascorbic acid. Subgroup 1b patients received only iron supplementation therapy. The group of comparison included 50 H. pylori-positive patients without coexistent iron deficiency who received the first line eradication therapy for 10 days as well. Presence of H. pylori infection and eradication control were carried out by urea breath test (Helic-test system). Efficacy of IDA treatment was evaluated by hemoglobin level, RBC color index, total iron-binding capacity (TIBC), serum ferritin and iron levels. Results. Patients were monitored with examination on the 14th, 28th and 56th days of treatment. Mean laboratory scores prior to onset of treatment in the subgroup 1a were: Нb 88,5 g/l, RBC 3,0×1012, RBC color index 0,74, serum iron 6,7 µmol/l, TIBC 89,4 µmol/l, transferrin saturation rate 9,3 %, ferritin 10,1 µg/l; in the subgroup 1B: 89,6 g/l, 3,1×1012, 0,75; 7,3 µmol/l, 88,6 µmol/l, 9,8%, 10,8 µg/l. At control examination in 28 days after iron supplementation onset positive changes were observed, that were more prominent in the subgroup 1a: Hb 117,8 g/l, RBC 3,9×1012, RBC color index 0,83, serum iron 17,7 µmol/l, TIBC 74,4 µmol/l, transferrin saturation percent 20,8 %, ferritin of 20,7 µg/l; in the subgroup 1B: 104,2 g/l, 3,6×1012, 0,81, 12,6 µmol/l, 79,2 µmol/l, 16,6 %, 17,9 µg/l respectively. Is also noticed that regression of anemia symptoms was more rapid than improvement of the laboratory scores especially in subgroup 1A patients. To 56th day of treatment all patients have reached target hemoglobin levels, that corresponded to a normal range. Conclusions. Eradication therapy in patients with iron deficiency anemia, allows to achieve improvement of both physical signs and the laboratory scores in shorter terms, as well as more rapid symptom relief. According to Maastricht IV consensus statements, all H. pylori-positive patients with idiopathic iron deficiency anemia require eradication therapy before onset of iron supplementation

The use of acoustic microscopy for biological tissue characterization

A system of transmission raster acoustic microscope with an ultrasound frequency of 450 MHz has been designed to investigate biological tissues and comparative analysis of their optical and acoustic images. The possibility of obtaining the contrast acoustic images of nonfixed, nonstained biological tissues and viscoelasticity measurements in microscale was demonstrated

Pleiotropic effects of rabeprazole at acid-related diseases

Aim of investigation. To study association interleukin-1 (IL-1) gene (rs16944), interleukin-6 (IL-6) gene (rs1800795), interleukin-10 (IL-10) gene (rs1800896) polymorphisms with development of acute pancreatitis (AP) in the Russian population. Material and methods. Whole blood samples were received from 297 AP patients and 238 healthy controls. Genotyping of IL-1 gene (rs16944) polymorphisms, IL-6 gene (rs1800795), IL-10 gene (rs1800896) was carried out by polymerase chain reaction with allele discrimination by TaqMan-probes. Results. The genetic polymorphism combination 511СТ×174GC of IL-1 and IL-6 genes was associated to high risk of AP development (OR=2.25, 95%-CI 1.45-3.49; p=0.0018). According to stratification analysis smoking patients with 511CT genotype had higher AP risk, then the patients with other genotypes (OR=2.22, 95%-CI 1.3-3.79; p=0.003). Paired combination of genotypes to disease risk analysis demonstrated that at 511СT×174GС genotype combination the AP risk is highest at alcohol abuse history for over 10 years (OR=2.88, 95%-CI 1.59-5.23; p=0.0004). Conclusion. Interleukin genetic polymorphism investigation may be useful at assessment of cytokine status in AP patients to predict the outcomes and to develop the personalized approach to treatment and prophylaxis

Esophageal adenocarcinoma: risk factors and modern screening strategy

Aim of review. To present the modern concepts on epidemiological pattern and risk factors of esophageal adenocarcinoma (EAC) and analyze the modern screening approach. Summary. In developed countries EAC is characterized by rapid increase of mobidity, as well as by high mortality level. As a rule, EAC is diagnosed at the late stage: diagnosis is often made at the 3rd or 4th stage of the tumor that is a major contributing factor for high mortality as treatment options at these stages are significantly limited. The basic established risk factor for EAC is the gastroesophageal reflux disease (GERD). EAC develops usually as a complication of the Barret's esophagus (BE) being a consequence of the long-standing GERD. Male gender, Caucasian race, obesity and metabolic syndrome, tobacco smoking, and series of genetic markers are considered to be significant EAC risk factors. A main goal of EAC screening programs is the early diagnosis that allows to improve patient survival. Conclusion. Only GERD patients develop EAC, with the highest risk in males, Caucasians, smokers, overweight patients and those with uncontrolled symptoms. Timely diagnosis of GERD, its effective treatment and follow-up of BE cases can prevent EAC development