55 research outputs found
MODERN PROBLEMS OF ENVIRONMENTAL CONTAMINATION BY PLASTIC AND WAYS OF THEIR SOLUTION
The article discusses the problem of large-scale pollution of the human environment by plastic, discusses the issues of obtaining, properties, advantages and using biodegradable polymer materials.В статье обсуждается проблема масштабного загрязнения среды обитания человека пластиком, рассматриваются вопросы получения, свойств, преимуществ и использования биоразлагаемых полимерных материалов
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Non-hemagglutinating flaviviruses: molecular mechanisms for the emergence of new strains via adaptation to European ticks
Tick-borne encephalitis virus (TBEV) causes human epidemics across Eurasia. Clinical manifestations range from inapparent infections and fevers to fatal encephalitis but the factors that determine disease severity are currently undefined. TBEV is characteristically a hemagglutinating (HA) virus; the ability to agglutinate erythrocytes tentatively reflects virion receptor/fusion activity. However, for the past few years many atypical HA-deficient strains have been isolated from patients and also from the natural European host tick, Ixodes persulcatus. By analysing the sequences of HA-deficient strains we have identified 3 unique amino acid substitutions (D67G, E122G or D277A) in the envelope protein, each of which increases the net charge and hydrophobicity of the virion surface. Therefore, we genetically engineered virus mutants each containing one of these 3 substitutions; they all exhibited HA-deficiency. Unexpectedly, each genetically modified non-HA virus demonstrated increased TBEV reproduction in feeding Ixodes ricinus, not the recognised tick host for these strains. Moreover, virus transmission efficiency between infected and uninfected ticks co-feeding on mice was also intensified by each substitution. Retrospectively, the mutation D67G was identified in viruses isolated from patients with encephalitis. We propose that the emergence of atypical Siberian HA-deficient TBEV strains in Europe is linked to their molecular adaptation to local ticks. This process appears to be driven by the selection of single mutations that change the virion surface thus enhancing receptor/fusion function essential for TBEV entry into the unfamiliar tick species. As the consequence of this adaptive mutagenesis, some of these mutations also appear to enhance the ability of TBEV to cross the human blood-brain barrier, a likely explanation for fatal encephalitis. Future research will reveal if these emerging Siberian TBEV strains continue to disperse westwards across Europe by adaptation to the indigenous tick species and if they are associated with severe forms of TBE
Surface decoration of silica nanoparticles by Pd(0) deposition for catalytic application in aqueous solutions
© 2015 Elsevier B.V.. The work introduces chemical and electrochemical synthetic routes to obtain Pd(0) nanoparticles (PdNPs) deposited onto silica supports in aqueous media. The former route is performed through reduction of Na2[PdCl4] by ascorbic acid in the presence of amino-modified silica nanoparticles (SiO2-NH2). The time-dependent variation of pH and the reductant concentration is the simple synthetic route to get uniform deposition of 215nm sized silica supports by Pd(0) nanoparticles (3-10nm). The methylviologen-mediated electrochemical synthetic route results in small PdNPs (3-9nm) located both onto and beyond the silica supports. Thus, the chemical synthetic route provides more homogeneous Pd(0)-SiO2-NH2 aqueous colloids. The results reveal that attractive interactions of amino/ammonium groups of SiO2-NH2 with both [PdCl4]2- and ascorbate-stabilized Pd(0) seeds are the key reasons for the better Pd(0)-deposition onto silica supports. The chemically deposited Pd(0)-SiO2-NH2 nanoparticles catalyze the chemiluminescence of luminol resulted from the H2O2-facilitated oxidation in alkaline aqueous solutions
Оценка чувствительности и специфичности ASAS-критериев для периферического спондилоартрита у пациентов с ранним псориатическим артритом
Objective: to estimate the sensitivity and specificity of ASAS (Assessment of Spondyloarthritis International Society) criteria for peripheral spondyloarthritis (SpA) in patients with early psoriatic arthritis (ePsA).Subjects and methods. Examinations was made in 45 patients (17 men and 28 women) with ePsA meeting the CASPAR (ClASsification criteria for Psoriatic ARthritis) criteria (mean age, 37 years; disease duration, 1 year) and in 20 patients (9 men and 11 women) with signs of peripheral SpA meeting the ESSG (European Spondyloarthropathy Study Group) criteria (mean age, 23 years; disease duration, 2.25 years; control group). The investigators estimated 78/76 tender/swollen joints and enthuses using MASES (Maastricht Ankylosing Spondylitis Enthesitis Score) and assessed the presence of inflammatory spinal pain according to the ASAS criteria, psoriasis, uveitis, inflammatory bowel diseases, genitourinary and/or enteric infections, and a family history of SpA. They also performed X-ray studies of the hand and distal portions of the foot and pelvis and graded sacroilitis using the Kellgren scores. HLA-B27, C-reactive protein, and erythrocyte sedimentation rate were determined. The sensitivity/specificity, likelihood ratios, and clinical value of criteria were calculated.Results. 41/4 and 31/14 patents with ePsA met/unmet Criteria Sets I and II. The sensitivity/specificity of Sets I and II was 91.1/10% and 68.8/95%, respectively. One patient with ePsA and two patients in the control group did not meet one of the sing sets. The total sensitivity/specificity was 97.8/10%. In the control group, the sensitivity/specificity of Sets I and II was 91.1/100% and 68.8/100%, respectively. For ePsA, the positive likelihood ratio proved to be high for Set II (13.78%) and low for Set I (1.01).Conclusion. ASAS Criteria Set I for peripheral SpA is of low value in identifying ePsA and Sign Set II shows a high value in diagnosing ePsA as it includes the major clinical manifestations of the disease. Both the ASAS for peripheral SpA and CASPAR criteria may be used for the classification of PsA.Цель исследования – определение чувствительности и специфичности критериев ASAS (Assesment of Spondyloarthriitis International Society) для периферического спондилоартрита (СпА) при раннем псориатическом артрите (рПсА).Материал и методы. Обследовано 45 больных (17 мужчин и 28 женщин) с рПсА, соответствующих критериям CASPAR (ClASsification criteria for Psoriatic ARthritis), средний возраст – 37 лет, длительность заболевания – 1 год и 20 больных (9 мужчин и 11 женщин) с признаками периферического СпА, соответствующих критериям ESSG (European Spondyloarthropathy Study Group), средний возраст – 23 года, длительность заболевания – 2,25 года (контрольная группа). Оценивали 78/76 болезненных/припухших суставов, энтезисы по MASES (Maastricht Ankylosing Spondylitis Enthesitis Score), наличие воспалительной боли в позвоночнике по критериям ASAS, псориаза, увеита, воспалительных заболеваний кишечника, мочеполовой и/или кишечной инфекции, семейный анамнез по СпА. Выполняли рентгенографию кистей, дистальных отделов стоп и таза, стадию сакроилиита оценивали по Kellgren. Опреде- ляли HLA-B27, СРБ, СОЭ. Рассчитывали чувствительность/специфичность, отношение правдоподобия результатов, клиническую значимость критериев.Результаты. 41/4 и 31/14 пациентов с рПсА соответствовали/не соответствовали I и II сету критериев. Чувствительность/специфичность I сета – 91,1/10%, II сета – 68,8/95%. 1 пациент с рПсА и 2 пациента в контрольной группе не соответствовали ни одному из сетов признаков. Общая чувствительность/специфичность – 97,8/10%. В контрольной группе чувствительность/специфичность I сета составила 91,1/100%, II сета – 68,8/100%. Для рПсА отношение правдоподобия положительного результата оказалось высоким для II (13,78) и низким для I (1,01) сета признаков.Заключение. I сет признаков критериев ASAS для периферического СпА имеет низкое значение для выявления рПсА, II сет показал высокую значимость для диагностики рПсА, так как включает основные клинические проявления заболевания. Для классификации ПсА могут быть использованы как критерии ASAS для периферического СпА, так и CASPAR
Results of long-term biological monitoring of pacific salmons in the hatcheries of Kamchatsky Krai
The following biological problems of the pacific salmons cultivation in Kamchatka are considered on the base of long-term monitoring data (2001-2013): 1) dynamics of cultivated salmons abundance in the water bodies of salmon hatcheries; 2) salmon otolith marking; 3) biological state of salmon juveniles and adults; 4) epizooty in hatcheries; 5) assessment of hatcheries effectiveness and prospects of salmon cultivation in Kamchatka. Four pacific salmon species are cultivated in Kamchatka: chum salmon (~ 60-70 %), sockeye salmon (~ 25-30 %), chinook salmon (~ 2-3 %), and coho salmon (~ 2-3 %). Their total annual release from Kamchatka hatcheries is estimated as approximately 36 million juveniles on average for the period 2001-2013. Mean contribution of chinook, sockeye and coho salmons cultivated in Kamchatka to the total release of these species from all Far-Eastern hatcheries is 100 %, 95 % and 35 %, respectively, but the contribution of chum salmon does not exceed 3-5 % of its total release. Total annual return of the salmons to Kamchatka hatcheries is about 38,000 on average, so the coefficients of return are usually < 1 % that means rather poor effectiveness of the hatcheries. The highest coefficient of return (2.1 %) is reached in Malkinsky hatchery that uses local geo-thermal water for rearing of salmon juveniles. To enhance the returns, illegal fishing (poaching) should be limited as much as possible and technologies of rearing have to be enhanced. Besides, the process of otoliths marking for cultivated juveniles in hatcheries has to be strictly controlled by technical standards for better evaluation of their contribution to commercial stocks. Promising ways of salmon fishery industry development in Kamchatka are ranching, supporting of wild salmon reproduction, and regulation of traditional fishery. All these measures should minimize effects of hatchery cultivation on structure of the stocks of pacific salmons. Health surveillance for hatchery-reared juveniles has to prevent and/or reduce their mortality in case of infectious, parasitical, alimentary and others diseases
ON THE TERMINOLOGY OF SPONDYLOARTHRITIS
By the end of the first decade of the 21st century, spondyloarthritis studies have accumulated a certain number of terms that are obsolete, but used by physicians in their everyday speech, on the one hand, and a great variety of different definitions, on the other hand. In January 2014, the first organizational meeting of the Expert Group on Spondyloarthritis, Association of Rheumatologists of Russia, decided that its primary task should be to order the terminology used in this area. The authors primarily collected the terms, which had been already used in medical vocabulary, and then divided them into two categories: obsolete definitions and terms to be finalized and unified. This publication gives guidelines for using the medical terms relevant to spondyloarthritis and separately discusses how to correctly write the term sacroiliitis
EFFICIENCY OF TRIPLE (METHOTREXATE + SULFASALAZINE + HYDROXYCHLOROQUINE) COMBINATION DISEASE-MODIFYING THERAPY VERSUS METOTREXATE MONOTHERAPY IN PATIENTS WITH RHEUMATOID ARTHRITIS
Objective: to compare the efficiency and tolerability of combination disease-modifying therapy with methotrexate (MT), sulfasalazine (SS), and hydroxychloroquine (HC) with that of MT monotherapy in patients with rheumatoid arthritis (RA). Subjects and methods. Sixty patients with RA, who had received no disease-modifying anti-inflammatory drugs, were enrolled in a 24-month open-label study. The patients were randomized into two groups at a 1:1 ratio. Group 1 received combination therapy with MT (its starting dose was 7.5 mg weekly), SS (2.0 g/day), and HC (200 mg/day); Group 2 had MT therapy. If there was no remission, the dose of MT was gradually increased from 7.5 to 17.5 mg weekly. The basic efficiency rate was a 50% improvement according to the American College of Rheumatologists criteria (ACR 50), which persisted at 9 months of therapy to the end of the study in the absence of adverse reactions (AR) requiring the therapy in question to be discontinued. Results. At 24 months of therapy, the effect corresponding to ACR 50 was observed in 16 (59.3%) of the 27 patients in Group 1 and in 11 (40.7%) of the 27 patients in Group 2 (p = 0.174). This effect persisted at 9 to 24 months in 9 (33.3%) patients in Group 1 and in 2 (7.4%) in Group 2 (p = 0.039). These patients had no AR that required treatment correction. By the end of the study, remission (DAS < 1.6) was seen in 6 (22.2%) patients in Group 1 and in 2 (7.4%) in Group 2 (p = 0.259). The groups showed no significant differences in the progression of X-ray signs of joint destruction. The assessment using the Sharp method indicated that the median erosion scores increased by a point in Groups 1 and 2; the median joint-space narrowing score rose by 8 and 7 points and the median total score increased by 10 and 6.5 points, respectively. There was a functional improvement in both groups. The median HAQ dropped from 1.5 to 0.5 scores in Group 1 and from 2.0 to 0.75 scores in Group 2. The tolerability of combination therapy and MT therapy did not differ greatly. Only 4 (13.3%) patients in Group 1 and 7 (23.3%) were withdrawn from the study because of AR. Conclusions. Combination disease-modifying therapy with MT, SS, and HC is more effective than MT monotherapy. Tolerability was comparable for both treatments
Spine inflammatory changes in patients with ankylosing spondylitis assessed by magnetic resonance image
Objective. To develop the optimal mode of spine evaluation with magnetic resonance image (MRl) in pts with ankylosing spondylitis (AS) and to study relationship between MR! signs of spinal inflammatory lesions (IL), spondylitis duration and clinical features of AS activity. Material and methods. MRl was performed in 36 pts (22 male, 14 female) fulfilling the modified NY criteria of AS. Median age of pis was 26 years (range 19 - 55), Median AS duration - 8 years (range 1,8 - 24). 34 (97%) pts were HLA-B27 positive. 21 (64%) pts had high AS activity - median BASDAI 40 (range 10 - 77). 92% of pts had inflammatory spine pain (VAS>20 mm) and 61% of pts had night pain. Median inflammatory pain duration had been defined separately for every part of the spine assessed by MRl. Median duration of axial pain was 36 months (range: 1-240). MR-scanning (Magnetom Symphony, Siemens, 1.5 T) was performed inTl, T2 and T2-FS (fat signal suppression) modes. IL scoring was done only in 29 pts evaluated in both sagittal and axial planes. We used two scoring methods: 1) individual IL score of the each spine element (vertebral bodies, processes, arches, zygapophyseai, costovertebral and costotransverse joints, ligaments), and 2) separate IL scoring in the vertebral bodies and posterior spinal elements in order "yes/no”. Results. 50 MRl images of different parts of the spine (8 cervical, 30 thoracic and 12 lumbar) have been obtained in 36 pts. Spine IL were found in 35 pts. 26% of all IL were revealed in axial planes. 3 pts with short AS duration had IL only on axial slices (zygapophyseai lumbar joints, costotransverse joints, processes). IL were revealed more often in thoracic (average score: 7.1), than in lumbar (3.7) and cervical (2.1) spine. In most (26 from 29 pts, 90%) pts IL were found in painful parts of spine. There was no IL score difference between pts(n=12) with low (BASDAI <40) and high (BASDAI>40; n=17) AS activity. Me and range were 4 (1.8-10.3) and 6 (4-16), respectively; p=0.35. There was also no difference in percent of images with IL between pts with short (Me: 4 months, range: 1-18; n= 10) and prolonged (Me: 54 months, range: 24-180; n=16) duration of spondylitis (100% and 94% of images, respectively). However, pts with early spondylitis had significantly more IL in posterior spinal structures than in vertebral bodies (92.3% and 23.1% images, respectively; p<0,001). Conclusion. Inflammatory MRl lesions are frequently observed in pts with active AS, more often in thoracic spine, and independently of spondylitis duration. Inflammatory MRl lesions in early spondylitis are revealed more often in posterior structures of spine. These results show the necessity to obtain MRl scans for early diagnosis of AS not only in sagittal but also in axial plane
Magnetic resonance imaging of sacroiliac joints in patients with seronegative spondyloarthritides
Objective. To study diagnostic possibilities of magnetic resonance imaging (MRI) of sacroiliac joints (SIJ) in pts with seronegative spondyloarthritides (SS). Material and methods. MRI and radiological examination was performed in 15 pts: 10 with ankylosing spondylitis (AS) and 5 with undifferentiated SS. MRI was done with Magnetom Symphony apparatus (Siemens, Germany) with magnetic-field strength 1,5 tesla. Tl, T2 and T2-FS weighted were used. Tl-FS weighted performed in 3-4 minutes after intravenous infusion of gadolinium were additionally used in 5 pts. Inflammatory and structural (erosions, subchondral sclerosis) MRI changes of SIJ were studied. Inflammatory changes of SIJ were analyzed in subchondral bone, bone marrow, joint capsule, joint cavity, interosseous ligaments. SS activity was assessed with BASDAI. Results. Median age of pts was 24 years, median SS duration — 3 years. HLA-B27 was revealed in 13 from 15 pts. All pts had radiological signs of sacroiliitis: 13 - bilateral (12 - II or III stage and 1 — I and III stage according to Kellgren), 2 — unilateral (II stage). So radiological signs of inflammation were revealed in 28 from 30 examined SIJ. MRI signs of sacroiliitis were present in the same 28 SIJ. Subchondral edema of sacrum and/or huckle-bone was revealed in 23 SIJ of 13 pts, bone marrow edema — in 20 SIJ of 13 pts, joint cavity edema - in 21 SIJ of 14 pts, capsule edema — in 12 SIJ of 8 pts, interosseous ligaments inflammation signs — in 3 SIJ of 2 pts. Inflammatory changes of all 5 examined anatomic structures were present in 1, 4 — in 9, 3 — in 13 SIJ. In 1 SIJ inflammation was localized in capsule only. Structural changes were revealed in 22 (73%) SIJ of 14 pts. Structural MRI changes of SIJ at II radiological stage of sacroiliitis were noted in 67% and at III stage — in 83%. Combination of inflammatory and structural changes was present in 22 from 30 SIJ (73%). Frequency of such combination was similar at different radiological stages of sacroiliitis. Isolated inflammatory signs without structural changes were present in 3 SIJ of 3 pts. Gadolinium administration allowed to reveal 5 additional edema zones in SIJ region of 4 from 5 pts. Inflammatory changes of SIJ were revealed with similar frequency in presence (81%) or absence (88%) of pain in this region. Pts with high (BASDAI>40) or not high (BASDAK40) general activity of the disease had about the same mean number of SIJ inflammatory changes (7,6 and 7,8 respectively). Conclusion. MRI is highly sensitive method for revealing SIJ changes in pts with SS. Inflammatory MRI changes were present in all joints with radiological changes irrespectively from radiological stage
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