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Peter ?alamún Marek Ren?o Eva Kucanová Tímea Brázová Ingrid Papajová Dana Miklisová Vladimíra Hanzelová 《Ecotoxicology (London, England)》2012,21(8):2319-2330
The effect of distance from a heavy metal pollution source on the soil nematode community was investigated on four sampling sites along an 4?km transect originating at the Kovohuty a.s. Krompachy (pollution source). The soil nematode communities were exposed to heavy metal influence directly and through soil properties changes. We quantified the relative effects of total and mobile fraction of metals (As, Cd, Cr, Cu, Pb, and Zn) on soil ecosystem using the nematode community structure (trophic and c-p groups,) and ecological indices (Richness of genera, H′, MI2-5, etc.). Pollution effects on the community structure of soil free living nematodes was found to be the highest near the pollution source, with relatively low population density and domination of insensitive taxa. A decrease in heavy metals contents along the transect was linked with an increase in complexity of nematode community. The majority of used indices (MI2-5, SI, H′) negatively correlated (P?<?0.05 or P?<?0.01) with heavy metals content and were sensitive to soil ecosystem disturbance. Contamination by heavy metals has negatively affected the soil environment, which resulted in nematode community structure and ecological indices changes. Results showed that the free-living nematodes are useful tools for bioindication of contamination and could be used as an alternative to the common approaches based on chemical methods. 相似文献
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Kalwak K Gorczyńska E Toporski J Turkiewicz D Slociak M Ussowicz M Latos-Grazyńska E Król M Boguslawska-Jaworska J Chybicka A 《British journal of haematology》2002,118(1):74-89
Immune reconstitution was studied prospectively in 66 children who underwent 77 haematopoietic cell transplantations (HCT): 46 autologous HCTs in 39 patients and 31 allogeneic HCTs in 27 patients. We studied the dynamic analysis of immune recovery with regard to potential factors affecting its speed, including age, type of HCT, diagnosis, graft-versus-host disease (GvHD) and cytomegalovirus (CMV) infection reactivation. Absolute counts of different lymphocyte subsets and immunoglobulin serum levels were determined in peripheral blood of patients on d -7 and +16, and then at various intervals up to 24 months post transplant. Common patterns of immune recovery after both allogeneic and autologous HCT were identified: (i) CD4+CD45RO+ peripheral T-cell expansion on d +16; (ii) inverted CD4+:CD8+ ratio from d +30 onwards; (iii) rapid natural killer (NK) cell (CD16+/-CD56+) count normalization. We observed prolonged T-cell lymphopenia (CD3+, CD3+CD4+, CD4+CD45RA+) until 24 months after autologous HCT, whereas in the allogeneic setting CD3+CD4+ cells, including naive CD45RA+ cells, returned to normal values at 9 months post transplant. Age > 10 years and coexistence of GvHD and CMV reactivation were associated with a substantial delay in T- (CD4+, including CD45RA+) and B-cell recovery after allogeneic HCT. Multidrug GvHD prophylaxis resulted in impaired T- (CD4+, CD4+CD45RA+) and B-cell reconstitution only in the early phase after allogeneic HCT (up to 4 months). Our results demonstrated that T-cell recovery was severely impaired in children after autologous HCT. It should be emphasized that specific approaches to enhance immune reconstitution are necessary to control minimal residual disease and avoid the risk of infectious complications in the autologous setting. Thymic involution after allogeneic HCT seems to be associated with age and coexistence of GvHD and CMV reactivation. 相似文献
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Duncan IC Gebka M Hellig F Cilliers A Klug E Harrisberg JR Govendrageloo K Middlemost SJ 《The Journal of invasive cardiology》2004,16(9):469-474
We describe four cases with symptomatic coronary artery fistulas that were treated primarily with endovascular cyanoacrylate embolization. Coils were also used as adjunctive embolic agents in two of these cases. All four cases showed symptomatic improvement after closure of the fistulas. Complications occurred in three cases including transient ST-segment elevation in one, symptomatic pulmonary embolization in a second, and transient pleuritic chest pain, pericarditis and acute renal failure in a third. The technical aspects of all four cases are given together with a review of the use of cyanoacrylate as an embolic material. We conclude that cyanoacrylate embolization could be considered as an alternative technique for the endovascular closure of coronary artery fistulas but must also caution that the use of this embolic agent is hazardous and should be restricted to practitioners experienced in its usage. 相似文献
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In order to learn the heterogeneity of the DNA of B. burgdorferi s.l. and the prevalence of co-infections of B. burgdorferi s.l. genospecies in the populations of I. ricinus, collected in north-western Poland, the nested PCR method was applied, a fragment of the fla gene being used as a marker. Basing on the prevalence data of B. burgdorferi s.l. DNA in I. ricinus ticks in 8 sampling sites during 1998-2001, it may be stated that a risk of contracting Lyme disease exists in forested areas of north-western Poland, the highest in relation to B. burgdorferi s.s. (76.3% infected ticks), lower by B. garinii (2% infected ticks), and minimal threat being posed by B. afzelii (0.3%). I. ricinus ticks collected in north-western Poland pose a risk of contracting double infection by B. burgdorferi s.l. genospecies, i.e. B. burgdorferi s.s. with B. garinii, and B. burgdorferi s.s. with B. afzelii. The north-western part of Poland represents an endemic area for B. burgdorferi s.l. 相似文献
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Sengupta PP Krishnamoorthy VK Abhayaratna WP Korinek J Belohlavek M Sundt TM Chandrasekaran K Seward JB Tajik AJ Khandheria BK 《The American journal of cardiology》2008,102(3):357-362
Brain (B-type) natriuretic peptide (BNP) and tissue Doppler imaging may distinguish restrictive cardiomyopathy (RCMP) from idiopathic constrictive pericardial disease (CP). However, their comparative efficacy is unknown for patients with CP from secondary causes (e.g., surgery or radiotherapy). We compared the efficacy of tissue Doppler imaging and BNP for differentiation of RCMP (n = 15) and CP (n = 16) were compared. BNP was higher in patients with RCMP than CP (p = 0.008), but the groups overlapped, particularly for BNP <400 pg/ml. BNP was lower with idiopathic CP than secondary CP (139 +/- 50 vs 293 +/- 69 pg/ml; p <0.001) or RCMP (139 +/- 50 vs 595 +/- 499 pg/ml; p <0.001), but not significantly different between those with secondary CP and RCMP (293 +/- 69 vs 595 +/- 499 pg/ml; p = 0.1). Patients with CP and RCMP had less overlap in early diastolic and isovolumic contraction tissue Doppler imaging velocities compared with BNP, with clear separation of groups evident with mean early diastolic annular velocities (averaged from 4 walls). Early diastolic tissue Doppler imaging velocity was superior to BNP for differentiation of CP and RCMP (area under the curve 0.97 vs 0.76, respectively; p = 0.01). In conclusion, mean early diastolic mitral annular velocity correctly distinguished CP from RCMP even when there was a large overlap of BNP between the 2 groups. 相似文献
100.
Chwyczko T Sterliński M Maciag A Firek B Labecka A Jankowska A Kośmicki M Kowalik I Malczewska B Szwed H 《Kardiologia polska》2008,66(4):406-12; discussion 413-4
BACKGROUND: Cardiac resynchronisation therapy (CRT) has become a valuable therapeutic tool in patients with advanced chronic heart failure (CHF). The search for optimal methods for the assessment of CRT efficacy is still underway. AIM: To evaluate the impact of implantation of CRT devices in patients with CHF on adaptation of circulatory and respiratory systems to maximal exercise assessed by cardiopulmonary exercise tests (CPX) and 6-minute walking tests (6MWT). METHODS: We investigated 27 patients (22 males, 5 females, 61.2+/-9.1 years) with a CRT device implanted due to advanced CHF, which resulted from ischaemic or dilated cardiomyopathy. All patients before implantation underwent echocardiography, CPX with expired gas analysis and 6MWT. Investigations were repeated at 3-6 months after CRT implantation. In CPX we evaluated peak oxygen uptake (peak VO2), oxygen pulse, maximal minute ventilation-carbon dioxide production (VE/VCO2 (max)), and its slope (VE/VCO2 slope) and VE/VO2 slope, VO2 in anaerobic threshold (AT), and cardiac and respiratory reserve. In 6MWT we evaluated walking distance and heart rate and blood pressure response to exercise. RESULTS: We noted statistically higher mean peak VO2 after CRT implantation in the studied group: 11.34+/-3.38 vs. 14.56+/-3.99 ml/kg/min (p<0.0001) and 1.01 +/-0.44 vs. 1.4+/-0.55 l/min (p=0.003) and higher values of expired CO2: 1.00+/-0.43 vs. 1.43+/-0.67 l/min (p=0.004). The O2 pulse rose from 9.65+/-3.39 to 13.23+/-5.43 ml/beat (p=0.015). We also observed a significant reduction of VE/VCO2 slope from 42.34+/-13.35 before CRT to 34.77+/-6.04 after CRT (p=0.0196) and a significant decrease of VE/VO2 slope from 41.32 +/-15.46 to 34.01+/-6.27 (p=0.037). VE/VCO2 (max) fell from 58.02+/-15.86 to 50.1+/-13.14 (p=0.009). Patients estimated their dyspnoea on the Borg scale at peak exercise at 4.75+/-0.75 points before CRT and at 3.67+/-1.15 points (p=0.002) after CRT. Patients could walk a longer distance during 6MWT than before CRT (367+/-154.9 vs. 231.1+/-170.3 m, p<0.001). CONCLUSIONS: Cardiac resynchronisation therapy improves exercise tolerance measured by means of CPX and 6MWT, improves respiratory system efficiency and restores its adaptive mechanisms during exercise in patients with advanced CHF. Better exercise adaptation after CRT may be objectively measured with CPX parameters, and correlates with improvement of clinical symptoms. CPX seems to be a very helpful tool in assessing the results of CRT. 相似文献