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41.
Di Iorio A Ferrucci L Sparvieri E Cherubini A Volpato S Corsi A Bonafè M Franceschi C Abate G Paganelli R 《Cytokine》2003,22(6):198-205
Interleukin-1 plays a role in normal homeostasis and in the inflammatory response which is deemed to be responsible for the development of major chronic diseases that are highly prevalent in the elderly. Aim of this study is to evaluate the factors influencing the serum levels of Interleukin-1 beta, in a large and representative population. Data were from the InCHIANTI project, a study of factors contributing to the decline of mobility in late life, which sampled people living in two sites in the surroundings of Florence. Blood samples were obtained from 1,292 participants and frozen aliquots were stored at -80 degrees C. The serum levels of several cytokines were measured by enzyme linked immunosorbent assay using an ultrasensitive commercial kit. Interleukin-1 beta serum levels were associated with congestive heart failure (p > 0.001) and angina (p = 0.02), with Ca2+ serum levels (p = 0.02), and with a history of dyslipidemia (p = 0.05). We found no association between serum IL-1beta level and age, sex, consumption of cardioactive drugs and serum levels of IL-1Ra, IL-6, sIL-6R, IL-10 and TNF-alpha. Our data could lend support to the hypothesis that IL-1beta is mainly involved in the functional alterations of cardiomyocytes under conditions marked by mononuclear cell infiltration and by downregulation of calcium. 相似文献
42.
Theodros Bedelu Amare Gessesse Dawit Abate 《World journal of microbiology & biotechnology》1998,14(5):731-734
A comparison of the nematode-destroying capability of two nematophagous Arthrobotrys spp. (coded ART-1 and ART-2), isolated from soil samples, showed that ART-1 (LD50=290conidia/ml) was more efficient than ART-2 (LD50=725conidia/ml). The two isolates produce extracellular proteases in liquid culture. The proteases from both isolates had a temperature optimum of 50°C. The optimum pH for protease activity was in the range of 7.5–8 for ART-1 and 7.5–9 for ART-2. ART-1 produced more protease activity (13.3±0.72U/ml) than ART-2 (10.9±0.375U/ml). The proteases from ART-1 were more efficient in degrading nematodes than those of ART-2 by virtue of being produced in a larger quantity. We suggest that the difference in the nematode-destroying capability between the two strains is solely the result of the difference in the amount of extracellular proteases they produce. 相似文献
43.
Baye Ashenefe Wassie Surafel Fantaw Yonas Mekonene Amete Mihret Teshale Yohannis Yitagesu Estifanos Tsige Desalegn Getahun Geremew Tasew Getachew Abichu Beyene Moges Ebba Abate Takele Abayneh Taye Zeru Zewdu Belay Siobhan M. Mor 《PLoS neglected tropical diseases》2022,16(2)
BackgroundAnthrax is a disease that affects humans and animals. In Ethiopia, anthrax is a reportable disease and assumed to be endemic, although laboratory confirmation has not been routinely performed until recently. We describe the findings from the investigation of two outbreaks in Amhara region.MethodsFollowing reports of suspected outbreaks in Wag Hamra zone (Outbreak 1) and South Gondar zone (Outbreak 2), multi-sectoral teams involving both animal and public health officials were deployed to investigate and establish control programs. A suspect case was defined as: sudden death with rapid bloating or bleeding from orifice(s) with unclotted blood (animals); and signs compatible with cutaneous, ingestion, or inhalation anthrax ≤7 days after exposure to a suspect animal (humans). Suspect human cases were interviewed using a standard questionnaire. Samples were collected from humans with suspected anthrax (Outbreak 1 and Outbreak 2) as well as dried meat of suspect animal cases (Outbreak 2). A case was confirmed if a positive test was returned using real-time polymerase chain reaction (qPCR).ResultsIn Outbreak 1, a total of 49 cows died due to suspected anthrax and 22 humans developed symptoms consistent with cutaneous anthrax (40% attack rate), two of whom died due to suspected ingestion anthrax. Three people were confirmed to have anthrax by qPCR. In Outbreak 2, anthrax was suspected to have caused the deaths of two livestock animals and one human. Subsequent investigation revealed 18 suspected cases of cutaneous anthrax in humans (27% attack rate). None of the 12 human samples collected tested positive, however, a swab taken from the dried meat of one animal case (goat) was positive by qPCR.ConclusionWe report the first qPCR-confirmed outbreaks of anthrax in Ethiopia. Both outbreaks were controlled through active case finding, carcass management, ring vaccination of livestock, training of health professionals and outreach with livestock owners. Human and animal health authorities should work together using a One Health approach to improve case reporting and vaccine coverage. 相似文献
44.
Ana Carolina Muro Emilio Rodríguez Carlos M. Abate Faustino Siñeriz 《Biotechnology letters》2000,22(20):1639-1642
Several levan hyperproducing mutants of Zymomonas mobilis strains were selected by mutagenesis with N-methyl-N-nitro-nitrosoguanidine and caffeine. Highest levan production (41 g l–1) was obtained with a mutant strain HL 29 in a culture medium containing 200 g sucrose l–1 and 0.5 g (NH4)2SO4 l–1 stored at 7 °C for 29 days. This is the first report describing the levan synthesis by Z. mobilis at 7 °C. 相似文献
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Previous research on warfare in a worldwide sample of societies by Ember and Ember (Journal of Conflict Resolution, 36, 242–262, 1992a) found a strong relationship between resource unpredictability (particularly food scarcity caused by natural disasters) in nonstate, nonpacified societies and overall warfare frequency. Focusing on eastern Africa, a region frequently plagued with subsistence uncertainty as well as violence, this paper explores the relationships between resource problems, including resource unpredictability, chronic scarcity, and warfare frequencies. It also examines whether resource scarcity predicts more resource-taking in land, movable property, and people, as well as the commission of atrocities. Results support previous worldwide results regarding the relationship between resource unpredictability and warfare frequency. Results regarding resource-taking and atrocities are more nuanced and complex. In almost all findings, relationships are generally in opposite directions in nonstate and state societies. In post-hoc analyses, atrocities are significantly more likely to be committed in states than in nonstates. 相似文献
48.
Alteration of bacterial communities and organic matter in microbial fuel cells (MFCs) supplied with soil and organic fertilizer 总被引:2,自引:0,他引:2
Stefano Mocali Carlo Galeffi Elena Perrin Alessandro Florio Melania Migliore Francesco Canganella Giovanna Bianconi Elena Di Mattia Maria Teresa Dell’Abate Renato Fani Anna Benedetti 《Applied microbiology and biotechnology》2013,97(3):1299-1315
The alteration of the organic matter (OM) and the composition of bacterial community in microbial fuel cells (MFCs) supplied with soil (S) and a composted organic fertilizer (A) was examined at the beginning and at the end of 3 weeks of incubation under current-producing as well as no-current-producing conditions. Denaturing gradient gel electrophoresis revealed a significant alteration of the microbial community structure in MFCs generating electricity as compared with no-current-producing MFCs. The genetic diversity of cultivable bacterial communities was assessed by random amplified polymorphic DNA (RAPD) analysis of 106 bacterial isolates obtained by using both generic and elective media. Sequencing of the 16S rRNA genes of the more representative RAPD groups indicated that over 50.4% of the isolates from MFCs fed with S were Proteobacteria, 25.1% Firmicutes, and 24.5% Actinobacteria, whereas in MFCs supplied with A 100% of the dominant species belonged to γ-Proteobacteria. The chemical analysis performed by fractioning the OM and using thermal analysis showed that the amount of total organic carbon contained in the soluble phase of the electrochemically active chambers significantly decreased as compared to the no-current-producing systems, whereas the OM of the solid phase became more humified and aromatic along with electricity generation, suggesting a significant stimulation of a humification process of the OM. These findings demonstrated that electroactive bacteria are commonly present in aerobic organic substrates such as soil or a fertilizer and that MFCs could represent a powerful tool for exploring the mineralization and humification processes of the soil OM. 相似文献
49.
Daniel Argaw Abate Mulugeta Mercè Herrero Nohelly Nombela Tsegemariam Teklu Teodros Tefera Zewdu Belew Jorge Alvar Caryn Bern 《PLoS neglected tropical diseases》2013,7(11)
Background
Visceral leishmaniasis is a lethal parasitic disease transmitted by phlebotomine sand flies. The largest focus of VL in Ethiopia is located in the lowland region bordering Sudan, where the epidemiology is complicated by the presence of thousands of seasonal agricultural workers who live under precarious conditions.Methodology/Principal Findings
We conducted two parallel case-control studies to identify factors associated with VL risk in residents and migrants. The studies were conducted from 2009 to 2011 and included 151 resident cases and 157 migrant cases, with 2 matched controls per case. In multivariable conditional regression models, sleeping under an acacia tree at night (odds ratios (OR) 5.2 [95% confidence interval 1.7–16.4] for residents and 4.7 [1.9–12.0] for migrants), indicators of poverty and lower educational status were associated with increased risk in both populations. Strong protective effects were observed for bed net use (OR 0.24 [0.12–0.48] for net use in the rainy season among residents, OR 0.20 [0.10–0.42] for any net use among migrants). For residents, living in a house with thatch walls conferred 5-fold and sleeping on the ground 3-fold increased risk. Among migrants, the risk associated with HIV status was borderline significant and sleeping near dogs was associated with 7-fold increased risk.Conclusions/Significance
Preventive strategies should focus on ways to ensure net usage, especially among migrant workers without fixed shelters. More research is needed to understand migration patterns of seasonal labourers and vector bionomics. 相似文献50.
Marta A. Polti Mariana C. AtjiánMaría J. Amoroso Carlos M. Abate 《International biodeterioration & biodegradation》2011,65(8):1175-1181
The aim of this work was to evaluate a strategy to reduce the bioavailable chromium fraction in soil, using a Cr(VI) resistant microorganism, Streptomyces sp. MC1, under non sterile conditions, with maize plants as bioindicator and/or bioremediator.Soil samples were contaminated with 100, 200 and 400 mg kg−1 of Cr(VI) or Cr(III). Bioavailable chromium (35%) was only detected in samples with Cr(VI). Soil samples with Cr(VI) 200 mg kg−1 were inoculated with Streptomyces sp. MC1, and bioavailable chromium decreased up to 73%.Zea mays seedlings were planted in soil samples contaminated with chromium. Plantlets accumulated chromium mainly as Cr(III), and biomass decreased up to 88%. Streptomyces sp. MC1 was inoculated in soil samples contaminated with 200 mg kg−1 of Cr(VI) and Z.mays seedlings were planted.Streptomyces sp. MC1 caused Z.mays biomass increase (57%), chromium accumulation and bioavailable chromium decreased up to 46% and 96%, respectively.This work constitutes the first contribution of cooperative action between actinobacteria and Z.mays in the bioremediation of Cr(VI) contaminated soil. The large removal capacity of bioavailable chromium by Streptomyces sp. MC1 and Z.mays infers that they could be successfully applied together in bioremediation of soils contaminated with Cr(VI). 相似文献