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131.
The DNA of fifteen Italian cultivars of durum wheat (Triticum turgidum L. ssp. durum) were analyzed by in fluorescence amplified fragment length polymorphism (fAFLP) in order to obtain the characteristic fingerprintings of genotypes and assess their genetic relatedness. Among 64 combinations of fluorescence labelled primers, three different combinations were chosen as producing a total of 6630 AFLP fragments, 2277 (34.3 %) of them being polymorphic. By using this fAFLP methodology a DNA fingerprinting of each durum wheat cultivar was generated for genotype identification. Analysis of the genetic relationships show the low variability among durum wheat cultivars. 相似文献
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133.
Roberta Battistini Elisa Marcucci Marco Verani Graziano Di Giuseppe Fernando Dini Annalaura Carducci 《European journal of protistology》2013,49(3):381-388
The aim of the present work was to study the dynamics of the interactions between human adenovirus and ciliates under both experimental and field conditions. Experimental co-cultures of the ciliated protozoan Euplotes octocarinatus and human adenovirus (HAdV) type 2 were established and virus internalization was investigated using nested PCR and direct immunofluorescence (IF). In addition, to study protozoa-virus interactions in the field, wild ciliates were isolated from active sludges of a wastewater treatment plant and analyzed for the presence of adenovirus using direct IF. In vitro experiments revealed HAdV type 2 inside Euplotes cells after 15 min of contact and its persistence until at least 35 days post infection. In addition, our results showed the adsorption of adenovirus on the surface of wild ciliates. We conclude that HAdV is taken up by ciliates, however more studies are necessary in order to better investigate the mechanisms, the infectivity of internalized virus and the protective effects of internalization against disinfection. 相似文献
134.
Nelson C. Di Paolo Lisa K. Baldwin Eric E. Irons Thalia Papayannopoulou Stephen Tomlinson Dmitry M. Shayakhmetov 《PLoS pathogens》2014,10(3)
Inflammation is a highly coordinated host response to infection, injury, or cell stress. In most instances, the inflammatory response is pro-survival and is aimed at restoring physiological tissue homeostasis and eliminating invading pathogens, although exuberant inflammation can lead to tissue damage and death. Intravascular injection of adenovirus (Ad) results in virus accumulation in resident tissue macrophages that trigger activation of CXCL1 and CXCL2 chemokines via the IL-1α-IL-1RI signaling pathway. However, the mechanistic role and functional significance of this pathway in orchestrating cellular inflammatory responses to the virus in vivo remain unclear. Resident metallophilic macrophages expressing macrophage receptor with collagenous structure (MARCO+) in the splenic marginal zone (MZ) play the principal role in trapping Ad from the blood. Here we show that intravascular Ad administration leads to the rapid recruitment of Ly-6G+7/4+ polymorphonuclear leukocytes (PMNs) in the splenic MZ, the anatomical compartment that remains free of PMNs when these cells are purged from the bone marrow via a non-inflammatory stimulus. Furthermore, PMN recruitment in the splenic MZ resulted in elimination of virus-containing cells. IL-1α-IL-1RI signaling is only partially responsible for PMN recruitment in the MZ and requires CXCR2, but not CXCR1 signaling. We further found reduced recruitment of PMNs in the splenic MZ in complement C3-deficient mice, and that pre-treatment of IL-1α-deficient, but not wild-type mice, with complement inhibitor CR2-Crry (inhibits all complement pathways at C3 activation) or CR2-fH (inhibits only the alternative complement activation pathway) prior to Ad infection, abrogates PMN recruitment to the MZ and prevents elimination of MARCO+ macrophages from the spleen. Collectively, our study reveals a non-redundant role of the molecular factors of innate immunity – the chemokine-activating IL-1α-IL-1RI-CXCR2 axis and complement – in orchestrating local inflammation and functional cooperation of PMNs and resident macrophages in the splenic MZ, which collectively contribute to limiting disseminated pathogen spread via elimination of virus-containing cells. 相似文献
135.
Francesco Migliavacca Giancarlo Pennati Elena Di Martino Gabriele Dubini Riccardo Pietrabissa 《Computer methods in biomechanics and biomedical engineering》2013,16(3):243-248
The modified Blalock-Taussig shunt is a surgical procedure used as a palliation to treat complex congenital heart defects. It consists of an interposing prosthetic tube between the innominate/subclavian artery and the right pulmonary artery. Previous experience indicates that the pressure drop across the shunt is affected by the pulmonary pressure at the distal anastomosis combined with the distensibility of the anastomosis. In this study, a computational fluid-structure interaction approach is presented to investigate the haemodynamic behaviour. Steady-state fluid dynamics and structural analyses were carried out using commercial codes based on the finite element method (FIDAP and ABAQUS) coupled by means of a purposely-developed procedure to transfer boundary conditions. Both prosthetic tube and artery walls were characterised by non-linear material properties. Three different pulmonary pressures (2, 5 and 15 mmHg) and two volume flow rates (0.4 and 0.8 l/min) were investigated. Results indicate that the effects of distensibility at the distal anastomosis on the shunt pressure drop are relevant only when the distal anastomosis on the shunt pressure drop are relevant only when the distal anastomosis is not fully distended, which occurs when the pulmonary pressure is lower than 5 mmHg. 相似文献
136.
Sidong Yang Wenyuan Ding Dalong Yang Tixin Gu Feng Zhang Di Zhang Yapeng Sun Lei Ma Yanli Song 《PloS one》2013,8(11)
Purpose
The purpose of this study was to describe the epidemiology of cervical spine injury in the patients with cervical trauma and analyze its associated risk factors during the special heating season in North China.Methods
This cross-sectional study investigated predictors for cervical spine injury in cervical trauma patients using retrospectively collected data of Hebei Provincial Orthopaedic Hospital from 11/2011 to 02/2012, and 11/2012 to 02/2013. Binary logistic regression analysis was used to determine risk factors for cervical fractures/dislocations or cord injury.Results
A total of 106 patients were admitted into this study. Of all, 34 patients (32.1%) were treated from 11/2011 to 02/2012 and 72 patients (67.9%) from 11/2012 to 02/2013. The mean age was 41.9±13.3 years old; 85 patients (80.2%) were male and 82 (77.4%) from rural areas. Eighty patients (75.5%) were caused by fall including 45 (42.5%) by severe fall (>2 m). Sixty-five patients (61.3%) of all suffered injuries to other body regions and 32 (30.2%) got head injury. Thirty-one patients (29.2%) sustained cervical cord injury with cervical fractures/dislocations. Twenty-six (83.9%) of cervical cord injury patients were from rural areas and 24 (77.4%) of those resulted from fall including 15 (48.4%) from severe fall (>2 m). Logistic regression displayed that age (OR, 1.47; 95% CI, 1.05–2.07), head injury (OR, 5.63; 95% CI, 2.23–14.26), were risk factors for cervical cord injury and snowing (OR, 8.25; 95% CI, 2.26–30.15) was a risk factor for cervical spine injury due to severe fall (>2 m).Conclusions
The elder male patients and patients with head trauma are high-risk population for cervical cord injury. As a seasonal factor, snowing during heating season is of note a risk factor for cervical spine injury resulting from severe fall (>2 m) in the patients with cervical trauma in North China. 相似文献137.
Allelic genes encoding water-borne signal proteins (pheromones) were amplified and sequenced from the somatic (macronuclear) sub-chromosomic genome of Antarctic and Arctic strains of the marine ciliate, Euplotes nobilii. Their open reading frames appeared to be specific for polypeptide sequences of 83 to 94 amino acids identifiable with cytoplasmic pheromone precursors (pre-pro-pheromones), requiring two proteolytic steps to remove the pre- and pro-segments and secrete the mature pheromones. Differently from most of the macronuclear genes that have so far been characterized from Euplotes and other hypotrich ciliates, the 5′ and 3′ non-coding regions of all the seven E. nobilii pheromone genes are much longer than the coding regions (621 to 700 versus 214 to 285 nucleotides), and the 5′ regions in particular show nearly identical sequences across the whole set of pheromone genes. These structural peculiarities of the non-coding regions are likely due to the presence of intron sequences and provide presumptive evidence that they are site of basic, conserved activities in the mechanism that regulates the expression of the E. nobilii pheromone genes. 相似文献
138.
139.
目的:探讨白藜芦醇(Res)是否通过下调ERK激酶/胞外信号调节激酶/原癌基因(MEK/ERK/c-Jun)信号通路抑制小剂量过氧化氢(H2O2)诱导肺癌细胞增殖。方法:采用MTS实验检测小剂量20μM H2O2以及分别加入MEK阻断剂U0126和Res后H2O2对肺癌细胞NCI-H1395增殖的影响,采用Western Blot检测H2O2对ERK1/2和Akt蛋白磷酸化水平以及加入Res后H2O2对MEK、ERK1/2和c-Jun蛋白磷酸化水平的影响。结果:小剂量H2O2对肺癌细胞NCI-H1395具有促增殖作用,H2O2通过活化ERK1/2和Akt蛋白的磷酸化水平促进肺癌细胞NCI-H1395增殖,加入MEK阻断剂U0126后H2O2对肺癌细胞NCI-H1395增殖作用降低(P<0.05)。Res可抑制H2O2诱导的肺癌细胞NCI-H1395增殖,加入Res后,H2O2引起的MEK、ERK1/2和c-Jun蛋白磷酸化水平均降低(P<0.05)。结论:小剂量H2O2对肺癌细胞NCI-H1395具有促增殖作用,Res通过抑制MEK/ERK/c-Jun信号通路来抑制H2O2对肺癌细胞NCI-H1395的促增殖作用,其具体机制还需进一步研究。 相似文献
140.
2018年初以来,北部湾涠洲岛附近出现了布氏鲸(Balaenoptera edeni)的活动。一头上颌与须板异常的小布氏鲸个体引发热议,其视频在网络上广泛流传。我们在船只调查时,目击该个体10次,其以单独活动为主(90%),主要出现在涠洲岛到斜阳岛之间的水域,最小凸多边形家域面积为14km2,核心家域面积为166.9km2。然而,在 2019年3月30日我们发现该个体已死亡漂浮在海面,根据尸体腐烂状况来推测,该个体的死亡时间大约为3~5日,死亡原因不明。根据照片和现场解剖分析,推测该小布氏鲸的上颌和鲸须异常可能是被渔网或绳索缠绕导致的。由于无法从外形上确认属于哪一个亚种,因此我们测定了该个体的线粒体DNA D-loop(mitochondrial DNA, mtDNA)和细胞色素b(cytochrome b, Cyt b)基因,分别得到909bp和395bp的序列,经比对和系统发育重建,发现该个体属于近岸分布的小布氏鲸亚种(Eden’s whale, B. e. edeni)。由于小布氏鲸具有一定季节迁移特性,我们无法判断造成其上颌伤害的渔网或绳索是否在中国水域。尽管如此,仍然建议当地部门应加强宣传,减少渔网等海洋垃圾的丢弃和排放,为小布氏鲸营造一个安全的栖息环境。 相似文献