44 research outputs found
HAUSGARTEN: Multidisciplinary investigations at a deep-sea, long-term observatory in the Arctic Ocean
The marine Arctic has played an essential role in the history of our planet over the past 130 million years and contributes considerably to the present functioning of Earth and its life. The global cycles of a variety of materials fundamental to atmospheric conditions and thus to life depend to a signifi cant extent on Arctic marine processes (Aargaard et al., 1999). The past decades have seen remarkable changes in key Arctic variables. The decrease of sea-ice extent and sea-ice thickness in the past decade is statistically signifi - cant (Cavalieri et al., 1997; Parkinson et al., 1999; Walsh and Chapman, 2001; Partington et al., 2003; Johannessen et al., 2004). There have also been large changes in the upper and intermediate layers of the ocean, which have environmental implications. For instance, the deep Greenland Sea has continued its decadal trend towards warmer and saltier conditions, with a corresponding decrease in oxygen content, refl ecting the lack of effective local convection and ventilation (Dickson et al., 1996; Boenisch et al., 1997). Changes in temperature and salinity and associated shifts in nutrient distributions will directly affect the marine biota on multiple scales from communities and populations to individuals, consequently altering food-web structures and ecosystem functioning (Benson and Trites, 2002; Moore, 2003; Schumacher et al., 2003; Wiltshire and Manly, 2004; Perry et al., 2005). Today, we do not know whether the severe alterations in abiotic parameters represent perturbations due to human impacts, natural long-term trends, or new equilibriums (Bengtson et al., 2004). Because Arctic organisms are highly adapted to extreme environmental conditions with strong seasonal forcing, the accelerating rate of recent climate change challenges the resilience of Arctic life (Hassol, 2004). The entire system is likely to be severely affected by changing ice and water conditions, varying primary production and food availability to faunal communities, an increase in contaminants, and possibly increased UV irradiance. The stability of a number of Arctic populations and ecosystems is probably not strong enough to withstand the sum of these factors, which might lead to a collapse of subsystems. To detect and track the impact of large-scale environmental changes in the transition zone between the northern North Atlantic and the central Arctic Ocean, and to determine experimentally the factors controlling deep-sea biodiversity, the German Alfred Wegener Institute for Polar and Marine Research (AWI) established the deepsea, long-term observatory HAUSGARTEN, representing the fi rst, and by now only, open-ocean, long-term station in a polar region
Challenges of Statin Therapy in Clinical Practice (According to Outpatient Register «PROFILE» Data)
Aim. To identify the main problems of statin therapy in patients with high and very high cardiovascular (CV) risk in real clinical practice.Material and methods. The general information of the study was based on data from 2,457 patients who were included in the register before November 30, 2020: 1,250 men (50.9%) and 1,207 (49.1%) women. A more detailed analysis was performed for groups of patients with high and very high CV risk who had indications for statin treatment at the time of inclusion in the register: out of 2457 patients, 1166 people had very high CV risk, 395 was at high CV risk (a total of 1561 people, the average age of patients was 64.4±11.0 years).Results. Information on the parameters of the lipidogram – the level of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) was available in 1918 (78.1%) and 1546 (62.9%) patients, respectively. Of 1561 patients with high and very high CV risk, TC and LDL-C levels were analyzed in 1221 (78.2%) and 956 (61.2%) cases, statistically significantly more often in patients with high CV risk (p<0.05). Statins were recommended only to 823 (52.7%) patients with high and very high CV risk. Patients with very high CV risk received such appointments 4 times more often than patients with high CV risk: odds ratio (OR) 4.2; 95% confidence interval (CI) 3.2-5.3 (p<0.001). Doctors preferred atorvastatin in prescriptions (n=456, 55.4%), rosuvastatin (n=244, 29.7%) and simvastatin (n=121, 14.7%) were in second and third places. The target level of LDLC was 2 times more often achieved in patients with high CVR, compared with patients with very high CV risk: OR = 2.0, 95% CI 1.4-3.0 (p<0.001).Conclusion. The main problems of statin treatment in real clinical practice remain the non-assignment of these drugs to patients who have indications for such therapy and the failure to achieve the target levels of lipidogram indicators, which may probably be due to the clinical inertia of doctors regarding titration of statin doses, and in some cases caused by the choice of drugs that are not the most effective in reducing LDL cholesterol. Patients with very high CV risk are 4 times more likely to receive a recommendation to take statins compared to patients with high CV risk, but the target level of LDL cholesterol is reached in them 2 times less often
Effect of benzoyl taurine dipotassium salt on coagulation, hemostasis and vascular activity in the microvasculature of the brain in violation of cerebral circulation
Cerebral circulation disorders (CCD) are one of the most common causes of mortality and disability in the population. Improving the microcirculation of brain tissue is one of the main directions in the treatment and prevention of CCD.Aim of the study was to evaluate the effect of a new derivative of hydroxybenzoic (salicylic) acid on neurological deficit, hemostasis and functional state of arterial pial vessels in the study of prostacyclin-synthetic activity and evaluation of NOmediated endothelial dysfunction in rats under experimental CCD conditions. Material and methods. The experiment was carried out on 50 Wistar rats, which were simulated for CCD by occlusion of common carotid arteries. Within 7 days after the operation, the animals received treatment according to the group: saline, C-60 (N-(3-hydroxybenzoyl)taurine dipotassium salt) and acetylsalicylic acid. After treatment, the activity of the prostacyclin-synthetic system was assessed by the reaction of pial vessels to indomethacin, endothelial dysfunction was estimated by tests with acetylcholine and L-NAME. The parameters of plasma and platelet hemostasis were also studied, and behavioral tests (open field, adhesion test, rotarod, Morris water maze, passive avoidance task) were used to assess neurological deficits in animals. Results. When studying the level of neurological deficit in animals with brain ischemia after a course of administration of the test compound, it was noted that in the treated groups, compared with the control group, there was a significant increase in motor and exploratory activity, improvement in sensory-motor function and coordination of movements (p < 0.05). Also, in the group treated with the salicylic acid derivative, normalization of the parameters of platelet and plasma hemostasis, improvement of the functional state of the vascular endothelium was observed. According to the results of assessing the prostacyclin-synthesizing activity of the endothelium of the cerebral vessels, it follows that the test compound inhibits cyclooxygenase at a level comparable with effect of acetylsalicylic acid. Conclusions. A new derivative of salicylic acid, the dipotassium salt of N-(3-hydroxybenzoyl)taurine, reduces the severity of neurological deficit, improves hemostasis parameters and the functional state of cerebral vessels in rats with brain ischemia in the experiment
Detection and Treatment of Hyperuricemia in Clinical Practice (According to the PROFILE Outpatient Registry)
Aim. To study the frequency of detection of hyperuricemia (HU) in patients with high and very high cardiovascular risk and the frequency of prescribing drugs that lower serum uric acid (sUA) levels in real clinical practice.Material and methods: The general information of the study was based on the data of 2457 patients who were consistently included in the «PROFILE» registry until November 30, 2020: 1250 men (50.9%) and 1207 (49.1%) women. All patients with HU were selected (UA level ≥360 pmol/l in women, ≥420 pmol/l in men). At the stage of inclusion of the patient, data on MC indicators were available in 1777 (72.3%), upon re-examination - only 262 (33.2%) out of 790 patients who returned to the appointment.Results: The most common study of the level of sUA was performed in patients with gout (65.2%), with arterial hypertension (AH) and dyslipemia in 29.1% of cases, with diabetes mellitus (DM) - 30.1%, with impaired tolerance to glucose (IGT) - 40.2%, with other diseases, the proportion of patients with a known UA was even less. A positive relationship was found between the presence of AH and IGT with the frequency of UA control (p<0.001). In patients with AH, an increase in the level of sUA was detected significantly more often than in patients without AH (p<0.001), and less frequently in patients with DM and IGT (p<0.001 and p<0.01, respectively). The frequency of allopurinol prescribing was low: 49 (2%) patients received therapy, while of the 284 patients with HU, only 20 (7%) were prescribed allopurinol.Conclusion: in real clinical practice, only 29.1% of patients with AH and 20-25% of patients with other CVDs were monitored for sUA levels, every third patient had data on sUA levels at a repeat visit. In the presence of gout, the proportion of patients with current UA was higher (65%). For those with AH and IGT, positive correlations were found between the presence of the disease and control of sUA levels. A low frequency of prescribing drugs for the correction of HU was revealed
Prehospital Period in Patients with COVID-19: Cardiovascular Comorbidity and Pharmacotherapy During the First Epidemic Wave (Hospital Registry Data)
Aim. Based on the data from the register of patients with COVID-19 and community-acquired pneumonia (CAP), analyze the duration of the prehospital period, cardiovascular comorbidity and the quality of prehospital pharmacotherapy of concomitant cardiovascular diseases (CVD).Material and methods. Patients were included to the study which admitted to the FSBI "NMHC named after N.I. Pirogov" of the Ministry of Health of the Russian Federation with a suspected or confirmed diagnosis of COVID-19 and/or CAP. The data for prehospital therapy, information from medical histories and a patients’survey in the hospital or by telephone contact 1-2 weeks after discharge were study. The duration of the prehospital stage was determined from the date of the appearance of clinical symptoms of coronavirus infection to the date of hospitalization.Results. The average age of the patients (n=1130; 579 [51.2%] men and 551 [48.8%] women) was 57.5±12.8 years. The prehospital stage was 7 (5,0; 10,0) days and did not differ significantly in patients with the presence and absence of CVD, but was significantly less in the deceased than in the surviving patients, as well as in those who required artificial lung ventilation (ALV). 583 (51.6%) patients had at least one CVD. Cardiovascular comorbidity was registered in 222 (42.7%) patients with hypertension, 210 (95.5%) patients with coronary heart disease (CHD), 104 (91.2%) patients with atrial fibrillation (AF). The inclusion of non-cardiac chronic diseases in the analysis led to an increase in the total proportion of patients with concomitant diseases to 65.8%. Approximately a quarter of hypertensive patients did not receive antihypertensive therapy, a low proportion of patients receiving antiplatelet agents and statins for CHD was revealed – 53% and 31.8%, respectively, anticoagulants for AF – 50.9%.Conclusion. The period from the onset of symptoms to hospitalization was significantly shorter in the deceased than in the surviving patients, as well as in those who required ALV. The proportion of people with a history of at least one CVD was about half of the entire cohort of patients. In patients with CVD before COVID-19 disease, a low frequencies of prescribing antihypertensive drugs, statins, antiplatelet agents and anticoagulants (in patients with AF) were recorded at the prehospital stage
Redescription and biology of Diopatra neapolitana (Annelida: Onuphidae), a protandric hermaphrodite with external spermaducal papillae
A one-year study of the reproductive biology of a population of Diopatra neapolitana at Villaviciosa estuary, northern Spain, was undertaken. Field observations together with a histological study of monthly collected individuals revealed that the population was iteroparous, had a discontinuous reproductive season with a resting period during August and September and a spawning season from March to July. The study showed that D. neapolitana was not dioecious as previously suggested but consisted of protandric sequential hermaphrodites, pure males and pure females with a male biased sex ratio of 3:1. During the peak reproductive period from May to August we observed simultaneous hermaphrodites with two dorsal papillae per segment in the branchial region. Histological studies demonstrated that the papillae were acting as seminal vesicles, storing own sperm, and also as sperm ducts, providing an exit route; hence we termed them 'spermaducal papillae'. The papillae are not the only sperm repositories as the coelom of males and simultaneous hermaphrodites in smaller size classes is also filled with sperm. The worms are broadcast spawners with a brief pelagic larval stage as previously reported but the finer points of this unusual fertilisation system need still to be elaborated. Diopatra cryptornata was recently described as a new species, supposedly differing from D. neapolitana in chaetal detail and the possession of the papillae. We have shown conclusively with morphological and genetical studies that the former species is a junior synonym of the latter. In the absence of type material we are here designating a neotype from recently collected material from Naples.17 page(s
Horizontal distribution patterns in arctic macrobenthic communities (Poster)
Horizontal distribution patterns of macrobenthos were studied based on material collected at the deep-sea long-term observatory HAUSGARTEN off West Spitsbergen (79°N) during the RV Polarstern expedition ARK XIX/3c in July-August 2003. Macofauna was obtained at water depths between 2500 and 2600 m. Samples were arranged using a hierarchical approach to analyze benthic fauna distribution at different scales. Three stations were performed along the 26 km transect. Three giant box-corers (0.25 m²) were taken at each station. Five subcores (12.5ґ12.5 cm) were extracted from each box corer. Total macrofauna biomasses varied from 2.31 g ww m2 to 6.41 g ww m2, and densities ranged from 1976 ind. m2 to 3254 ind. m2. Both qualitative and quantitative methods of statistical analysis confirmed that all samples belong to one benthic community with the dominant species complex Tetractinomorpha gen.sp. K_Diastylis K_polaris K_Myriochele K_heeri K_Galathowenia K_fragilis. The inner heterogeneity in species relative abundance and composition was found at a sub-community level. Multivariate analysis showed the division of all samples into two clear groups on the subcore and corer levels. The set of species at the lowest examined level (i.e. in a subcore) allowed the identification of two types of benthic sub-communities. The size of these sub-communities appeared to be not less than several km across. The hierarchical organization of benthic communities on the continental slope off Spitsbergen includes at least two levels: communities, which replace each other along the depth gradient (Wlodarska-Kowalczuk et al. 2004), and sub-communities which make up the orthogonal inner mosaics in each vertical zone. Wlodarska-Kowalczuk, M., M.A. Kendall, J.-M. Weslawski, M. Klages, T. Soltwedel. 2004. Depth gradients of benthic standing stock and diversity on the continental margin at a high latitude ice-free site (off West Spitsbergen, 79°N). Deep-Sea Research I, 51: 1903-1914
Properties and Hydrolysis Behavior of Celluloses of Different Origin
The present paper is a fundamental study on the physicochemical properties and hydrolysis behavior of cellulose samples differing in origin: bacterial, synthetic, and vegetal. Bacterial cellulose was produced by Medusomyces gisevii Sa-12 in an enzymatic hydrolyzate derived from oat-hull pulp. Synthetic cellulose was obtained from an aqueous glucose solution by electropolymerization. Plant-based cellulose was isolated by treatment of Miscanthus sacchariflorus with dilute NaOH and HNO3 solutions. We explored different properties of cellulose samples, such as chemical composition, degree of polymerization (DP), degree of crystallinity (DC), porosity, and reported infrared spectroscopy and scanning electron microscopy results. The hydrolysis behavior was most notable dependent on the origin of cellulose. For the bacterial cellulose sample (2010 DP, 90% DC, 89.4% RS yield), the major property affecting the hydrolysis behavior was its unique nanoscale reticulate structure promoting fast penetration of cellulases into the substrate structure. The study on enzymatic hydrolysis showed that the hydrolysis behavior of synthetic and Miscanthus celluloses was most influenced by the substrate properties such as DP, DC and morphological structure. The yield of reducing sugars (RS) by hydrolysis of synthetic cellulose exhibiting a 3140 DP, 80% DC, and highly depolymerization-resistant fibers was 27%. In contrast, the hydrolysis of Miscanthus-derived cellulose with a 1030 DP, 68% DC, and enzyme-accessible fibers provided the highest RS yield of 90%. The other properties examined herein (absence/presence of non-cellulosic impurities, specific surface, pore volume) had no considerable effect on the bioconversion of the cellulosic substrates