778 research outputs found
Skeletally Dugundji spaces
We introduce and investigate the class of skeletally Dugundji spaces as a
skeletal analogue of Dugundji space. The main result states that the following
conditions are equivalent for a given space : (i) is skeletally
Dugundji; (ii) Every compactification of is co-absolute to a Dugundji
space; (iii) Every -embedding of the absolute in another space is
strongly -regular; (iv) has a multiplicative lattice in the sense of
Shchepin \cite{s76} consisting of skeletal maps
Changes in the prevalence of atrial fibrillation in the Russian population over a 13-year follow-up
AIM: To study the prevalence of atrial fibrillation (AF) in the Russian urban population cohort aged 45-69 years and its changes over 13-year follow-up during aging.
MATERIAL AND METHODS: This cross-sectional long-term prospective study included random population sample of men and women 45-69 years (n=9360, HAPIEE project, Novosibirsk), which was examined in 2003-2005 and was re-examined twice and followed up for about 13±1,00 years in men and 13,1±2,17 years in women. The incidence of AF was assessed for individuals without AF or cardiovascular disease (CVD) at the baseline examination. Statistical analysis was performed using the SPSS software package (v.13.0).
RESULTS: In a population sample over a 13-year follow-up, AF prevalence increased from 1,6% (1,1% among women and 2,1% among men) at the age of 45-69 years to 4,2% (3,0% among women and 6,1% among men) aged 55-84 years according to screening rest ECG examinations. The prevalence of new AF cases over a 13-year followup in the cohort of 45-69 years old without previous CVD and AF was 5,6%, of which 40% were paroxysmal. The mean age at the time of first registered AF was 69±6,93 years, and was 2 years higher in women (70,0±6,83) than in men (68±6,93). The average period before the AF onset among people aged 45-69 years without baseline CVD and AF was 7,5±3,83 years for men and 8,1±4,02 years for women. The total prevalence of AF in the population sample was 8,3%. The highest AF prevalence was registered at the age of 65-69 years (11,4%) for men and 5 years later for women (12,0%) (p80 years decreased and amounted to 4,1% among men and 5,7% among women.
CONCLUSION: In the Russian population sample (Novosibirsk) aged 45-69, the AF prevalence increased from 1,6 to 8,3% over 13 years of follow-up. In addition, 473 new AF cases were identified, ~40% of which were paroxysmal AF. The prevalence of AF in the Siberian population sample for the 45-60 years age group is comparable with the large Russian and North American studies, but higher for persons aged 60-74 years and lower for older age group, for both men and women
MICROSCOPIC DIAGNOSTIC FEATURES OF WHOLE, MILLED AND POWDERED PLANT MATERIAL “RHIZOMES OF COMMON TURMERIC”
Aim - the determination of microscopic diagnostic features of rhizomes of common turmeric (Curcuma longa L.), ginger family (Zingiberaceae). Materials and methods. We have studied whole, milled and powdered plant material of turmeric from different manufactures. The study was carried out with the use of the digital microscopes “Motic DM111” (Korea) and “Motic DM-39C-N9GO-A” (Korea). Results. It was determined that the microscopic diagnostic features of rhizomes of turmeric include the presence of cells with sinuous walls and structured content in the form of colored folding in the parenchyma; closed collateral vascular bundles lie scattered in the parenchyma, their conductive elements have narrow lumen. Vascular bundles contain pigment cells considerably smaller in comparison with the size of vessels. Pigment cells with drops of orange-red essential oil are also found in the parenchyma. In milled and powdered plant material, the fragments of all these elements are observed. In the fragments of powdered rhizomes of turmeric, numerous cells with yellow content are found; the parenchyma cells have less expressed folded structure. Fragments of vessels are found both in milled and powdered material. Conclusion. The results of this study were included in the section “Microscopy” of the project of pharmacopoeial monograph “Curcuma longa L. rhizomes”
Social network analysis shows direct evidence for social transmission of tool use in wild chimpanzees
The authors are grateful to the Royal Zoological Society of Scotland for providing core funding for the Budongo Conservation Field Station. The fieldwork of CH was funded by the Leverhulme Trust, the Lucie Burgers Stichting, and the British Academy. TP was funded by the Canadian Research Chair in Continental Ecosystem Ecology, and received computational support from the Theoretical Ecosystem Ecology group at UQAR. The research leading to these results has received funding from the People Programme (Marie Curie Actions) and from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007–2013) REA grant agreement n°329197 awarded to TG, ERC grant agreement n° 283871 awarded to KZ. WH was funded by a BBSRC grant (BB/I007997/1).Social network analysis methods have made it possible to test whether novel behaviors in animals spread through individual or social learning. To date, however, social network analysis of wild populations has been limited to static models that cannot precisely reflect the dynamics of learning, for instance, the impact of multiple observations across time. Here, we present a novel dynamic version of network analysis that is capable of capturing temporal aspects of acquisition-that is, how successive observations by an individual influence its acquisition of the novel behavior. We apply this model to studying the spread of two novel tool-use variants, "moss-sponging'' and "leaf-sponge re-use,'' in the Sonso chimpanzee community of Budongo Forest, Uganda. Chimpanzees are widely considered the most "cultural'' of all animal species, with 39 behaviors suspected as socially acquired, most of them in the domain of tool-use. The cultural hypothesis is supported by experimental data from captive chimpanzees and a range of observational data. However, for wild groups, there is still no direct experimental evidence for social learning, nor has there been any direct observation of social diffusion of behavioral innovations. Here, we tested both a static and a dynamic network model and found strong evidence that diffusion patterns of moss-sponging, but not leaf-sponge re-use, were significantly better explained by social than individual learning. The most conservative estimate of social transmission accounted for 85% of observed events, with an estimated 15-fold increase in learning rate for each time a novice observed an informed individual moss-sponging. We conclude that group-specific behavioral variants in wild chimpanzees can be socially learned, adding to the evidence that this prerequisite for culture originated in a common ancestor of great apes and humans, long before the advent of modern humans.Publisher PDFPeer reviewe
Isolation of a wide range of minerals from a thermally treated plant: Equisetum arvense, a Mare’s tale
Silica is the second most abundant biomineral being exceeded in nature only by biogenic CaCO3. Many land plants (such as rice, cereals, cucumber, etc.) deposit silica in significant amounts to reinforce their tissues and as a systematic response to pathogen attack. One of the most ancient species of living vascular plants, Equisetum arvense is also able to take up and accumulate silica in all parts of the plant. Numerous methods have been developed for elimination of the organic material and/or metal ions present in plant material to isolate biogenic silica. However, depending on the chemical and/or physical treatment applied to branch or stem from Equisetum arvense; other mineral forms such glass-type materials (i.e. CaSiO3), salts (i.e. KCl) or luminescent materials can also be isolated from the plant material. In the current contribution, we show the chemical and/or thermal routes that lead to the formation of a number of different mineral types in addition to biogenic silica
Prevalence of transfusion-transmitted Chagas disease among multitransfused patients in Brazil
<p>Abstract</p> <p>Background</p> <p>Blood transfusion has always been an important route for Chagas Disease (CD) transmission. The high prevalence of CD in Latin America and its lifelong asymptomatic clinical picture pose a threat for the safety of the blood supply. The outcome of measures designed to improve transfusion safety can be assessed by evaluating the prevalence of CD among multitransfused patients</p> <p>Methods</p> <p>In order to assess the impact of CD control measures on the safety of the blood supply, an observational cross-sectional study was designed to determine the prevalence of CD in 351 highly transfused patients, in which vectorial transmission was excluded. This study compared patients that received transfusion products before (n = 230) and after (n = 121) 1997, when measures to control transfusion-transmitted CD were fully implemented in Brazil.</p> <p>Results</p> <p>The study group consisted of 351 patients exposed to high numbers of blood products during their lifetime (median number of units transfused = 51, range 10–2086). A higher prevalence of transfusion-transmitted CD (1.30%) was observed among multitransfused patients that received their first transfusion before 1997, compared with no cases of transfusion-transmitted CD among multitransfused patients transfused after that year. The magnitude of the exposure to blood products was similar among both groups (mean number of units transfused per year of exposure = 25.00 ± 26.46 and 23.99 ± 30.58 respectively; P = 0.75, Mann-Whitney test).</p> <p>Conclusion</p> <p>Multiple initiatives aimed to control vector and parental transmission of CD can significantly decrease transfusion-transmitted CD in Brazil. Our data suggest that mandatory donor screening for CD represents the most important measure to interrupt transmission of CD by blood transfusions.</p
[Morphology of collagen matrices for tissue engineering (biocompatibility, biodegradation, tissue response)]
Objective: to perform a comparative morphological study of biocompatibility, biodegradation, and tissue response to implantation of collagen matrices (scaffolds) for tissue engineering in urology and other areas of medicine. Material and methods. Nine matrix types, such as porous materials reconstructed from collagen solution; a collagen sponge-vicryl mesh composite; decellularized and freeze-dried bovine, equine, and fish dermis; small intestinal submucosa, decellularized bovine dura mater; and decellularized human femoral artery, were implanted subcutaneously in 225 rats. The tissues at the implantation site were investigated for a period of 5 to 90 days. Classical histology and nonlinear optical microscopy (NLOM) were applied. Results. The investigations showed no rejection of all the collagen materials. The period of matrix bioresorption varied from 10 days for collagen sponges to 2 months for decellularized and freeze-dried vessels and vicryl meshes. Collagen was prone to macrophage resorption and enzymatic lysis, being replaced by granulation tissue and then fibrous tissue, followed by its involution. NLOM allowed the investigators to study the number, density, interposition, and spatial organization of collagen structures in the matrices and adjacent tissues, and their change over time during implantation. Conclusion. The performed investigation could recommend three matrices: hybrid collagen/vicryl composite; decellularized bovine dermis; and decellularized porcine small intestinal submucosa, which are most adequate for tissue engineering in urology. These and other collagen matrices may be used in different areas of regenerative medicine
Is testosterone responsible for athletic success in female athletes?
BACKGROUND: The aim of this study was to determine the interrelationship between the resting serum testosterone (T) levels of female athletes from different types of sporting events and their athletic success. METHODS: The study involved 599 Russian international-level female athletes (95 highly elite, 190 elite, and 314 sub-elite; age: 16-35 years) and 298 age-matched female controls. The athlete cohort was stratified into four groups according to event duration, distance, and type of activity: 1) endurance athletes; 2) athletes with mixed activity; 3) speed/strength athletes; 4) sprinters. Athletic success was measured by determining the level of achievement of each athlete. RESULTS: The mean T levels of athletes and controls were 1.65±0.87 and 1.76±0.6 nmol/L (P=0.057 for difference between groups) with ranges of 0.08-5.82 and 0.38-2.83 nmol/L in athletes and controls, respectively. T levels were positively associated with athletic success in sprinters (P=0.0002 adjusted for age) only. Moreover, none of the sub-elite sprinters had T>1.9 nmol/L, while 50% of elite and highly elite sprinters had T>1.9 nmol/L (OR=47.0; P<0.0001). CONCLUSIONS: Our data suggest that the measurement of the serum T levels significantly correlates with athletic success in sprinters but not other types of athletes and in the future may be useful in the prediction of sprinting ability
Neurovasculature of high and low tie ligation of the inferior mesenteric artery
PURPOSE: Controversy exists as to whether a high or low tie ligation of the inferior mesenteric artery (IMA) is the preferred technique in surgeries of the left colon and rectum. This study aims to contribute to the discussion as to which is the more beneficial technique by investigating the neurovasculature at each site. METHODS: Ten embalmed cadaveric donors underwent division of the inferior mesenteric artery at the level of the low tie. The artery was subsequently ligated at the root to render a section of tissue for histological analysis of the proximal (high tie), mid and distal (low tie) segments. RESULTS: Ganglia observed in the proximal end of seven specimens in the sample imply that there would be disruption to the innervation in a high tie procedure. CONCLUSION: This study suggests that a high tie should be avoided if the low tie is oncologically viable
First-Line Therapy for Patients with Advanced Hodgkin’s Lymphoma: Efficacy and Toxicity of Intensive ЕАСОРР-14 Program (NN Blokhin National Medical Cancer Research Center Data)
Aim. To assess the efficacy and toxicity of intensive 6 courses EACOPP-14 treatment with or without radiotherapy (RT) for advanced stages of Hodgkin’s lymphoma (HL).
Materials & Methods. From November 2009 to February 2015, 95 patients with advanced stages of HL (IIX–IIE, III–IV) aged between 17 and 50 years (median 29 years) were selected for the participation in the protocol ЛХМосква1-3. The study population consisted of 46.3 % men and 53.7 % women. The results of the treatment were assessed in 91 patients who have received more than 2 courses of EACOPP-14. The follow up period was at least 3 months after the receiving the therapy. Consolidation RT with a total dose of 30 Gy for residual tumor lesions and/or initially large tumors was performed after the chemotherapy.
Results. Complete remission was achieved in 82 (90.1 %) patients, partial remission in 2 (2.2 %), and the progression was observed in 7 (7.7 %) patients. The overall 4-year survival rate was 90.8 %, the progression-free survival was 88.2 %. The toxicity of the ЕАСОРР-14 program was slightly lower than that of 8 courses of ВЕАСОРРesc, and was comparable to the toxicity of other modifications of intensified ВЕАСОРР scheme. Hematological toxicity grade 3 and 4 was most commonly observed: leukopenia was observed after 64.9 % of courses, anemia — after 24 % of courses, thrombocytopenia — after 3.8 % of courses. The rate of infections did not singificantly differ and accounted for 24 %. The most frequent non-infectious complications were mucositis (21.1 %) and polyneuropathy (11.7 %). Complications resulted in the change of treatment in only 3 (3.01 %) of patients. The exclusion of bleomycine from the ЕАСОРР-14 program reduced the frequency of RT complications. Grade 3 pulmonitis developed in 4.5 % of cases, while radiation-induce pulmonary fibrosis verified by CT developed in 15.2 % of cases. The ЕАСОРР-14 6 courses program showed its high efficacy both with and without RT, high tolerance and the possibility of full administration for the majority of patients with the various stages of HL.
Conclusion. Current research showed the efficacy of treatment without RT for patients with advanced stages of HL with negative PET results and small (< 2.5 cm) residual tumors after intensive ЕАСОРР-14 program. This approach allowed to avoid a number of late treatment complications
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