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1.
Ciprofloxacin induced an increment of reactive oxygen species in sensitive strains of Staphylococcus aureus leading to oxidative stress detected by chemiluminescence while resistant strains did not suffer such stress. Oxidation of lipids was performed by employing thiobarbituric acid reaction to detect the formation of the amplified intermediate between reactive species oxygen and cytoplasmic macromolecules, namely malondialdehyde (MDA). The sensitive strain presented higher peroxidation of lipids than the resistant strain. The oxidative consequence for DNA was investigated by means of bacteria incubation with ciprofloxacin and posterior extraction of DNA, which was studied by high performance liquid chromatography (HPLC). Sensitive S. aureus ATCC 29213 showed an increase of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) respect controls without antibiotic; there was evident increase of the ratio between 8-oxodG and deoxyguanosine (dG) as a consequence of oxidation of dG to 8-oxodG considered the major DNA marker of oxidative stress. The resistant strain showed low oxidation of DNA and the analysis of 8-oxodG/dG ratio indicated lesser formation of 8-oxodG than S. aureus ATCC 29213. 相似文献
2.
Mudge J Miller NA Khrebtukova I Lindquist IE May GD Huntley JJ Luo S Zhang L van Velkinburgh JC Farmer AD Lewis S Beavis WD Schilkey FD Virk SM Black CF Myers MK Mader LC Langley RJ Utsey JP Kim RW Roberts RC Khalsa SK Garcia M Ambriz-Griffith V Harlan R Czika W Martin S Wolfinger RD Perrone-Bizzozero NI Schroth GP Kingsmore SF 《PloS one》2008,3(11):e3625
3.
Summary This article presents some statistical methods for estimating the parameters of a population dynamics model for annual plants. The model takes account of reproduction, immigration, seed survival in a seed bank, and plant growth. The data consist of the number of plants in several developmental stages that were measured in a number of populations for a few consecutive years; they are incomplete since seeds could not be counted. It is assumed that there are no measurement errors or that measurement errors are binomial and not frequent. Some statistical methods are developed within the framework of estimating equations or Bayesian inference. These methods are applied to oilseed rape data. 相似文献
4.
Oluwatosin Adekeye Kim Ozano Ruth Dixon Elisabeth Osim Elhassan Luret Lar Elena Schmidt Sunday Isiyaku Okefu Okoko Rachael Thomson Sally Theobald Laura Dean 《PLoS neglected tropical diseases》2020,14(11)
Nigeria has the highest burden of NTDs in sub-Saharan Africa. Commitments to reach the control and elimination of many Neglected Tropical Diseases (NTDs), particularly those amenable to preventive chemotherapy (onchocerciasis, schistosomiasis, soil transmitted helminths, lymphatic filariasis and trachoma) by 2020 are detailed in the London declaration. Strategies to reach targets build on existing approaches, one of which is the use of community directed intervention (CDI) methods to deliver the mass administration of medicines (MAM). However, treatment using this approach has been inconsistent and there are questions about the acceptability and adaptability of these interventions during periods of programmatic, social, and political change. This paper explores the current strengths and weaknesses of CDI approaches in MAM delivery. We consider the acceptability and adaptability of existing MAM approaches to ensure equity in access to essential treatments. Using qualitative methods, we explore implementer perspectives of MAM delivery. We purposively selected programme implementers to ensure good programmatic knowledge and representation from the different levels of health governance in Nigeria. Data collection took place across two States (Kaduna and Ogun). Our results indicate that CDI approaches have underpinned many historic successes in NTD programme acceptance in Nigeria, specifically in Kaduna and Ogun State. However, our results also show that in some contexts, factors that underpin the success of CDI have become disrupted presenting new challenges for programme implementers. Capturing the tacit knowledge of health implementers at varying levels of the health system, we present the current and changing context of MAM delivery in Kaduna and Ogun States and consolidate a platform of evidence to guide future programme delivery and research studies. We situate our findings within the broader NTD literature, specifically, in identifying how our findings align to existing reviews focused on factors that shape individual acceptance of MAM. 相似文献
5.
Narci Romain Delattre Maud Larédo Catherine Vergu Elisabeta 《Journal of mathematical biology》2022,84(4):1-31
Journal of Mathematical Biology - Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infection worldwide, resulting in approximately sixty thousand annual... 相似文献
6.
L. E. Laróvere J. P. O'Neill M. Randall L. D. Fairbanks N. Guelbert L. Czornyj 《Nucleosides, nucleotides & nucleic acids》2013,32(3):255-258
Hypoxanthine-guanine phosphoribosyltransferase (HPRT) deficiency is an inborn error of purine metabolism responsible for Lesch-Nyhan Disease (LND) and its partial phenotypes, HPRT-related hyperuricemia with neurologic dysfunction (HRND) and hyperuricemia alone. We report here the recognition of six Argentine patients, two with LND and four with HRND. All patients presented elevated excretion of uric acid, hypoxanthine, and xanthine and decreased HPRT enzyme activities <1 nmol/h/mg Hb. The molecular analysis demonstrated in the two LND patients a novel inherited transition mutation, c.203T >C (L68P), in one subject and a germline transition mutation, c.209G >A (G70E), in the other. In the HRND patients a novel transversion mutation, c.584 A >C (Y195S), was found in three related patients and an inherited transition mutation, c.143G >A (R48H), in the fourth subject. 相似文献
7.
Hanegraaf Randall Larçin Atakan Jonker Nicole Mandley Steven Miedema Jelle 《The International Journal of Life Cycle Assessment》2020,25(1):120-140
The International Journal of Life Cycle Assessment - This study quantifies the impact of the Dutch cash payment system on the environment and on climate change using a life cycle assessment (LCA).... 相似文献
8.
V. V. Kolpakov T. V. Bespalova N. Yu. Lar’kina K. A. Lebedeva E. A. Tomilova T. F. Belova 《Human physiology》2009,35(5):600-611
Results of longitudinal studies were used to estimate the psychophysiological characteristics of preschool and young school
children and young adults of both sexes belonging to functional types (FTs) with low, medium, and high habitual physical activity
(HPA) levels (FT-1, LHPA; FT-2, MHPA, and FT-3, HHPA, respectively). Statistical analysis of the distributions of averaged
psychophysiological parameters in the total sample with the use of the χ2 and λ tests showed wide quantitative and qualitative ranges of psychophysiological individuality in a healthy population
and demonstrated that it is reasonable to distinguish three typological groups (FT-1, FT-2, and FT-3). Typical first- and
second-order parameters, as well as the results of third-order tests characterizing the current state, were determined for
each FT. Determination of the psychophysiological characteristics of FT-1, FT-2, and FT-3 and their prevailing behavioral
tendencies makes it possible to differentiate between strategies of organism-environment interaction and estimate their advantages
and disadvantages. 相似文献
9.
David O Larédo C Leblois R Schaeffer B Vergne N 《Journal of computational biology》2012,19(3):271-278
DNA barcoding is the assignment of individuals to species using standardized mitochondrial sequences. Nuclear data are sometimes added to the mitochondrial data to increase power. A barcoding method for analysing mitochondrial and nuclear data is developed. It is a Bayesian method based on the coalescent model. Then this method is assessed using simulated and real data. It is found that adding nuclear data can reduce the number of ambiguous assignments. Finally, the robustness of coalescent-based barcoding to departures from model assumptions is studied using simulations. This method is found to be robust to past population size variations, to within-species population structures, and to designs that poorly sample populations within species. Supplementary Material is available online at www.liebertonline.com/cmb. 相似文献
10.
M. F. Chauvin C. Bolon A. Conjard G. Martin B. Ferrier M. Martin C. Michoudet D. Durozard M. C. Laréal C. Gauthier H. Simonnet M. Elhamri S. Dugelay B. Joly G. Baverel 《Cell biology and toxicology》1996,12(4-6):283-287
Among the cellular models used in in vitro renal pharmacotoxicology, isolated kidney tubules, used as suspensions mainly of proximal tubules, offer important advantages. They can be prepared in large amounts under nonsterile conditions within 1–2 h; thus, it is possible to employ a great number of experimental conditions simultaneously and to obtain rapidly many experimental results. Kidney tubules can be prepared from the kidney of many animal species and also from the human kidney; given the very limited availability of healthy human renal tissue, it is therefore possible to choose the most appropriate species for the study of a particular problem encountered in man. Kidney tubules can be used for screening and prevention of nephrotoxic effects and to identify their mechanisms as well as to study the renal metabolism of xenobiotics. When compared with cultured renal cell, a major advantage of kidney tubules is that they remain differentiated. The main limitations of the use of kidney tubules in pharmacotoxicology are (1) the necessity to prepare them as soon as the renal tissue sample is obtained; (2) their limited viability, which is restricted to 2–3 h; (3) the inability to expose them chronically to a potential nephrotoxic drug; (4) the inability to study transepithelial transport; and (5) the uncertainty in the extrapolation to man of the results obtained using animal kidney tubules. These advantages and limitations of the use of human and animal kidney tubules in pharmacotoxicology are illustrated mainly by the results of experiments performed with valproate, an antiepileptic and moderately hyperammonemic agent. The fact that kidney tubules, unlike cultured renal cells, retain key metabolic properties is also shown to be of the utmost importance in detecting certain nephrotoxic effects. 相似文献