18 resultados para Obp
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The free-base octabromotetraphenylporphyrin (H2OBP) has been prepared by a novel bromination reaction of (meso-tetraphenylporphyrinato)copper(II). The metal [V(IV)O, Co(II), Ni(II), Cu(II), Zn(II), Pd(II), Ag(II), Pt(II)] derivatives exhibit interesting electronic spectral features and electrochemical redox properties. The electron-withdrawing bromine substituents at the pyrrole carbons in H2OBP and M(OBP) derivatives produce remarkable red shifts in the Soret (50 nm) and visible bands (100 nm) of the porphyrin. The low magnitude of protonation constants (pK3 = 2.6 and pK4 = 1.75) and the large red-shifted Soret and visible absorption bands make the octabromoporphyrin unique. The effect of electronegative bromine substituents at the peripheral positions of the porphyrin has been quantitatively analyzed by using the four-orbital approach of Gouterman. A comparison of MO parameters of MOBP derivatives with those of the meso-substituted tetraphenylporphyrin (M(TPP)) and unsubstituted porphine (M(P)) derivatives provides an explanation for the unusual spectral features. The configuration interaction matrix element of the M(OBP) derivatives is found to be the lowest among the known substituted porphyrins, indicating delocalization of ring charge caused by the increase in conjugation of p orbitals of the bromine onto the ring orbitals. The electron-transfer reactivities of the porphyrins have been dramatically altered by the peripheral bromine substituents, producing large anodic shifts in the ring and metal-centered redox potentials. The increase in anodic shift in the reduction potential of M(OBP)s relative to M(TPP)s is found to be large (550 mV) compared to the shift in the oxidation potential (300 mV). These shifts are interpreted in terms of the resonance and inductive interactions of the bromine substituents.
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Hypertension is one of the major risk factors for cardiovascular morbidity. The advantages of antihypertensive therapy have been clearly demonstrated, but only about 30% of hypertensive patients have their blood pressure (BP) controlled by such treatment. One of the reasons for this poor BP control may lie in the difficulty in predicting BP response to antihypertensive treatment. The average BP reduction achieved is similar for each drug in the main classes of antihypertensive agents, but there is a marked individual variation in BP responses to any given drug. The purpose of the present study was to examine BP response to four different antihypertensive monotherapies with regard to demographic characteristics, laboratory test results and common genetic polymorphisms. The subjects of the present study are participants in the pharmacogenetic GENRES Study. A total of 208 subjects completed the whole study protocol including four drug treatment periods of four weeks, separated by four-week placebo periods. The study drugs were amlodipine, bisoprolol, hydrochlorothiazide and losartan. Both office (OBP) and 24-hour ambulatory blood pressure (ABP) measurements were carried out. BP response to study drugs were related to basic clinical characteristics, pretreatment laboratory test results and common polymorphisms in genes coding for components of the renin-angiotensin system, alpha-adducin (ADD1), beta1-adrenergic receptor (ADRB1) and beta2-adrenergic receptor (ADRB2). Age was positively correlated with BP responses to amlodipine and with OBP and systolic ABP responses to hydrochlorothiazide, while body mass index was negatively correlated with ABP responses to amlodipine. Of the laboratory test results, plasma renin activity (PRA) correlated positively with BP responses to losartan, with ABP responses to bisoprolol, and negatively with ABP responses to hydrochlorothiazide. Uniquely to this study, it was found that serum total calcium level was negatively correlated with BP responses to amlodipine, whilst serum total cholesterol level was negatively correlated with ABP responses to amlodipine. There were no significant associations of angiotensin II type I receptor 1166A/C, angiotensin converting enzyme I/D, angiotensinogen Met235Thr, ADD1 Gly460Trp, ADRB1 Ser49Gly and Gly389Arg and ADRB2 Arg16Gly and Gln27Glu polymorphisms with BP responses to the study drugs. In conclusion, this study confirmed the relationship between pretreatment PRA levels and response to three classes of antihypertensive drugs. This study is the first to note a significant inverse relation between serum calcium level and responsiveness to a calcium channel blocker. However, this study could not replicate the observations that common polymorphisms in angiotensin II type I receptor, angiotensin converting enzyme, angiotensinogen, ADD1, ADRB1, or ADRB2 genes can predict BP response to antihypertensive drugs.
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ZnO thin film bulk acoustic resonators (FBARs) with resonant frequency of ∼1.5 GHz have been fabricated to function as an odorant biosensor. Physical adsorption of an odorant binding protein (AaegOBP22 from Aedes aegypti) resulted in frequency down shift. N,N-diethyl-meta-toluamide (DEET) has been selected as a ligand to the odorant binding protein (OBP). Alternate exposure of the bare FBARs to nitrogen flow with and without DEET vapor did not cause any noticeable frequency change. However, frequency drop was detected when exposing the OBP loaded FBAR sensors to the nitrogen flow containing DEET vapor against nitrogen flow alone (control) and the extent of frequency shift was proportional to the amount of the protein immobilized on the FBAR surface, indicating a linear response to DEET binding. These findings demonstrate the potential of binding protein functionalized FBARs as odorant biosensors. © 2012 Elsevier B.V. All rights reserved.
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自20世纪60年代以来,探索全球性气候变化规律和环境变迁史的研究工作在世界各国广泛开展。大规模的深海岩芯的研究、中国北方黄土的系统研究、大型湖泊沉积岩芯的研究及对树木年轮、泥炭、珊瑚、冰芯等“自然环境历史档案”开展的研究工作,都为重建古气候和古生态环境提供了大量的资料。洞穴化学沉积物(石笋)由于其特有的微层结构及其内的稳定氧、碳同位素和微量元素所蕴含的古气候与古生态环境信息,并且具有分布广、时间长、信息保存完整等特点,因此,它是研究地球环境变化很好的自然环境历史档案。本论文通过对凉风洞洞穴体系的综合研究和对凉风洞石笋(微层)生长特征及石笋的碳、氧稳定同位素组成的研究,系统探讨了贵州凉风洞石笋的古气候记录和古生态环境意义,得出以下主要结论:1,地表植被的类型及生物量等信息可综合反映于洞穴体系的不同组.分(气样、土样、水样)中。而洞穴的水动力条件也能很好的被洞穴滴水中所含微量(常量)元素记录。根据分析,洞穴综合体系对外界气候与生态环境的响应关系存在一定规律性。通过对比说明,我们所选的凉风洞基岩的溶蚀和缓冲对水体中的信息影响不大,即洞穴滴水较好的继承了土壤水所携带的地表气候与生态环境信息,是理想的研究对象。2.凉风洞石笋具有多个沉积旋回,不同沉积旋回的纹层组合及纹层结构存在一定的差异,指示不同的沉积环境。根据年龄数据判断,旋回①至旋回⑧之间年龄跨度为1570-8000 aBP,以呈缓平顶(柱)对称叠复状的沉积形态组合为主,示洞顶滴水量较大,滴水点相对稳定,且均匀,与全新世较为稳定的气候与环境变化的主旋律相一致。旋回⑧以下至底部石葡萄状沉积物之上部分之间年龄跨度为8000-14220 aBP,期间经历末次冰期晚期向全新世大暖期过渡,受诸如新仙女木事件(Younger Dryas)等的影响,气候变化幅度大,且经历多次反复,石笋生长的沉积学特征表现为斜锥(柱)、尖顶锥不对称叠复纹层组合,示洞顶滴水水量较小但变化较大,且洞穴滴水不稳(固)定。与此时间段内不稳定的气候与环境变化的主旋律也相一致。3.凉风洞石笋上段微层具有典型南方石笋微层发育的特性:微层发育较差,层面多弯曲,层间界面模糊等。下段因为沉积间断较多、风化层面厚及受到若干时段内碳酸钙重结晶而导致晶体穿插层位生长的影响,尽管在某些层位有微层发育,但无法对石笋微层作连续观察记录。根据高精度的石笋TIMS、ICP-MS测年数据和在显微镜下所数石笋微层数量的对比,扣除若干个沉积间断及风化层导致的微层缺失,以及显微镜下肉眼对细小微层计数的误差,我们认为,凉风洞石笋微层是年生长层的可能性较大。4,由于部分测年数据仍在测试中,目前无法精确控制石笋中沉积间断的存在导致的信息缺失,因此,我们仅仅根据部分石笋测年数据,建立了凉风洞石笋在不同时段的生长速率。全新世以来石笋的生长速率在22μm/yr-51μm/yr之间,明显高于末次冰期晚期向全新世过渡这一时间段内的石笋生长速率(16μm/yr)。这些数据间接印证了石笋生长响应于外界气候,尤其是降雨的变化。5.通过对洞穴体系的综合分析对比,我们判断凉风洞洞穴综合体系相对完整,洞穴化学沉积物的6先值较为直接的响应了土壤c压的61t值变化,即反映了地表的植被(c3植物和c;植物)的组成状况。贵州地区降雨80%集中在5-10月份,在此期间,基本受西南季风和东亚季风所控制。西南季风盛行时贵州各地的降雨频繁,是一年中雨量最集中的时期,在东亚季风影响时期,贵州多晴少雨,往往形成干早的天气。又西南季风控制区大气降雨创的值的加权平均值明显低于东亚季风控制区大气降雨δ18O值的加权平均值。因此,贵州地区年均降雨量和年均降雨δ18O值主要取决于西南(印度洋)季风的强弱:西南季风加强,降雨量增加,年均降雨剐、值偏负;西南季风减弱,降雨量减少,年均降雨δ18O值偏正。洞穴滴水的6旧O值变化基本继承了大气降水的别勿值变化。因此,对地处我国西南地区贵州南部的凉风洞,源于洞穴滴水的凉风洞石笋的别勺值变化直接响应了外界的大气降雨量的变化和西南季风与东亚季风相互的强弱交替。6.对凉风洞石笋碳、氧同位素组成的时间序列曲线作20点移动平均,发现,特别是进入全新世后,石笋的引3c值和扩、值几乎具有完全一致的同步变化,只是在变化幅度上在某些时段存在差异。说明在凉风洞石笋反映的14220-1570 aBP时间段内,尤其是10500-1570 aBP期间,本区域气候具有雨热(或干冷)同期的气候特征:在气温较高时间段,西南季风增强,气候湿润多雨,更有利于地表。植物的生长。气温降低时,随着东亚季风增强,西南季风减弱,气候干旱少雨,地表C;植物的生长占有一定的比例。据此重建和恢复了本地区14220-1570 aBP期间的古气候和古生态环境:(1).14220-10500aBP,处于末次冰期晚期,气温较低。凉风洞石笋此时段的司、值都大于-9.8‰,最小值为-9.31‰,最大值达-7.290‰,平均值为-8.552‰。说明凉风洞洞穴地表的生长植被。植物占有一定的组分,石笋的δ18C值受C3植物和C4植物的共同影响。此时段内石笋6、值也存在一定的波动(-5.651‰-6.942‰),考虑到末次冰期晚期先全新世过渡期间气温变幅较大,O'Neil等(1969)所建立的氧同位素平衡分馏方程中的温度变化已不能忽略,并且大气降雨的温度效应作用也比较明显,因此我们对此时段的季风和大气降雨量的变化不作讨论。(2). 10500-9300 aBP,新仙女木事件结束,进入全新世,气温逐渐回升。凉风洞石笋此时段的扩3c值大都小于-9.8‰,最小值为-10.377‰,最大值为-9.267‰,平均值为-9.910‰。凉风洞洞穴地表植被已逐渐由C3植物占主导。此时段石笋δ18C值明显卜降,最小值为-7.420‰,最大值为-6.077‰,平均值为-6.854‰。反映在全新世早期夏季风盛行,降雨量较大,西南季风对本地区全年降雨贡献率大。(3).9300-8300 aBP,经历一段明显温度波动变化。仟3c值在-9.8‰上下波动,最小值为-10.155‰,最大值为-9.096‰,平均值为-9.712‰。凉风洞洞穴地表植被C4植物所占比例存在反复。此时段石笋岁a0值变化幅度不是很大,最小值为-6.796‰,最大值为-6.260‰,平均值为-6.490‰。受冬季风影响,夏季风有一定的减弱,总体降雨量一般,东亚季风对本地区全年降雨贡献率比全新世初期有所增大。(4).8300-3l000BP,俗称全新世大暖期,此时段全球气温明显回升,石笋δ18C值总体逐渐降低,最小值为-n.926编,平均值为-10.496‰。凉风洞洞穴地表植被基本由C3植物所控制。但在扩飞值总体逐渐降低的趋势一F,也存在若干扩3c值明显增大时段,如7700-6700 aBP时段,61七值最大值达-8.110‰,地表C4植物所占比例已不能忽略。此时段石笋6150值变化幅度较大,最小值为-7.373‰,最大值为-5.047‰,平均值为-6.261‰。反映在全新世大暖期的大背景下西南季风和东亚季风的交替以及大气降雨量的变化存在较大的波动,说明了季风气候的不稳定性。(5).3100-1570 aBP,在3100aBP前后,凉风洞石笋的δ18C值和δ18O值均急剧上升,标志进入晚全新世。此时段气温变幅很大,δ18C值总体虽然仍偏低,平均值为-10.275‰,但刻畜介于-6.495-12.097‰之间;δ18C值平均值为-6.184‰,变幅介于-4.677-8.65‰之间,均超过以往任何时段。此时段凉风洞洞穴地表植被基本上仍然由C。植物所控制,始于3100 aBP的急速降温事件使得在全新世晚期开始时段C4植物所占比例有一定的上升。此时段内西南季风和东亚季风反复多次交替,大气降雨量存在较大幅度的变化,说明了季风气候在此时段的很不稳定性。对于169于巧70 oBP百年时间段内石笋的δ18C值和司、值巨大幅度的急剧升高,有待进一步研究,也不排除石笋表层长期裸露受外界污染所致。
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La presente investigación analiza el diálogo que se estableció entre distintos grupos de mujeres: religiosas, laicas e indígenas con la Teología de la Liberación y la influencia que ejerció Monseñor Leonidas Proaño en el compromiso pastoral y socio-político que asumieron las mujeres en Riobamba y Quito Sur durante las décadas de 1970 y 1980. La confluencia entre las mujeres y la Teología de la Liberación ocurre desde los inicios de la década del 1970. A ellas se las encuentra en los distintos espacios de acción pastoral que se lleva adelante en la Diócesis de Riobamba como en las comunidades religiosas insertas, comunidades eclesiales de base, equipos de pastoral, campañas de alfabetización, grupos de cantoras y aportes a la reflexión teológica. En la parroquia Quito sur la vinculación de las mujeres con la pastoral liberadora se refleja en las memorias a partir de la década de 1980. A través de la memoria y los testimonios de las mujeres que fueron partícipes de la pastoral liberadora, se reconstruye esta historia de aportes a los procesos históricos que realizan las mujeres desde la Teología de la Liberación y la incidencia que ésta ejerce en el empoderamiento y construcción de nuevas identidades. Desde las comunidades de base y a través de la metodología del “ver, juzgar y actuar”, las mujeres realizaron un cuestionamiento a las desigualdades sociales y una crítica a la propia Teología de la Liberación que asume los problemas de exclusión social, pero deja a un lado la exclusión de género. La incursión de las mujeres en los espacios de compromiso socio-político y pastoral supuso procesos permanentes de deconstrucción y reelaboración de su identidad, en los que dan cuenta de tensiones entre la invisibilización y desvalorización de sus experiencias.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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High Throughput Sequencing capabilities have made the process of assembling a transcriptome easier, whether or not there is a reference genome. But the quality of a transcriptome assembly must be good enough to capture the most comprehensive catalog of transcripts and their variations, and to carry out further experiments on transcriptomics. There is currently no consensus on which of the many sequencing technologies and assembly tools are the most effective. Many non-model organisms lack a reference genome to guide the transcriptome assembly. One question, therefore, is whether or not a reference-based genome assembly gives better results than de novo assembly. The blood-sucking insect Rhodnius prolixus-a vector for Chagas disease-has a reference genome. It is therefore a good model on which to compare reference-based and de novo transcriptome assemblies. In this study, we compared de novo and reference-based genome assembly strategies using three datasets (454, Illumina, 454 combined with Illumina) and various assembly software. We developed criteria to compare the resulting assemblies: the size distribution and number of transcripts, the proportion of potentially chimeric transcripts, how complete the assembly was (completeness evaluated both through CEGMA software and R. prolixus proteome fraction retrieved). Moreover, we looked for the presence of two chemosensory gene families (Odorant-Binding Proteins and Chemosensory Proteins) to validate the assembly quality. The reference-based assemblies after genome annotation were clearly better than those generated using de novo strategies alone. Reference-based strategies revealed new transcripts, including new isoforms unpredicted by automatic genome annotation. However, a combination of both de novo and reference-based strategies gave the best result, and allowed us to assemble fragmented transcripts.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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BACKGROUND: Aedes aegypti mosquitoes are the main vectors of dengue viruses. Despite global efforts to reduce the prevalence of dengue using integrated vector management strategies, innovative alternatives are necessary to help prevent virus transmission. Detailed characterizations of Ae. aegypti genes and their products provide information about the biology of mosquitoes and may serve as foundations for the design of new vector control methods. FINDINGS: We studied the Ae. aegypti gene, AAEL010714, that encodes a two-domain odorant-binding protein, AaegOBP45. The predicted gene structure and sequence were validated, although single nucleotide polymorphisms were observed. Transcriptional and translational products accumulate in the ovaries of blood fed females and are not detected or are at low abundance in other tissues. CONCLUSIONS: We validated the Ae. aegypti AAEL010714 gene sequence and characterized the expression profile of a two-domain OBP expressed in ovaries. We propose that AaegOBP45 function as a component of the mosquito eggshell.
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The herpes simplex virus type 1 origin of DNA replication, oriS, contains three copies of the recognition sequence for the viral initiator protein, origin binding protein (OBP), arranged in two palindromes. The central box I forms a short palindrome with box III and a long palindrome with box II. Single-stranded oriS adopts a conformation, oriS*, that is tightly bound by OBP. Here we demonstrate that OBP binds to a box III–box I hairpin with a 3′ single-stranded tail in oriS*. Mutations designed to destabilize the hairpin abolish the binding of OBP to oriS*. The same mutations also inhibit DNA replication. Second site complementary mutations restore binding of OBP to oriS* as well as the ability of mutated oriS to support DNA replication. OriS* is also an efficient activator of the hydrolysis of ATP by OBP. Sequence analyses show that a box III–box I palindrome is an evolutionarily conserved feature of origins of DNA replication from human, equine, bovine, and gallid alpha herpes viruses. We propose that oriS facilitates initiation of DNA synthesis in two steps and that OBP exhibits exquisite specificity for the different conformations oriS adopts at these stages. Our model suggests that distance-dependent cooperative binding of OBP to boxes I and II in duplex DNA is succeeded by specific recognition of a box III–box I hairpin in partially unwound DNA.
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National Highway Traffic Safety Administration, Washington, D.C.
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National Highway Traffic Safety Administration, Office of Driver and Pedestrian Research, Washington, D.C.
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Transportation Department, Office of University Research, Washington, D.C.
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Transportation Department, Office of University Research, Washington, D.C.