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161.
162.
The purpose of this article is to describe and analyze the edTPA, a performance assessment created by the Stanford Center for Assessment, Learning, and Equity (SCALE) and administered by Pearson, Inc., to assess the professional readiness of student teachers. We challenge claims made in support of using this assessment, specifically within the context of arts teacher preparation programs, and we address areas of immediate critical concern to make alternative recommendations.  相似文献   
163.
Abstract

The ability of mature, freeze‐thawed bovine sperm to bind exogenous end‐labelled or oligo‐labelled λ Hind III DNA restriction fragments was examined. Following 30 min. incubation of bovine sperm with P32 end‐labelled λ Hind III DNA and five washes with medium, approximately 5.8 ng DNA were bound to 107 sperm. Agarose gel autoradiography revealed that all of the λ Hind III DNA bands were present following sperm washes except for the smaller 0.5 Kb and 0.125 Kb bands. Incubation of sperm with 3H oligo‐labelled λ Hind III DNA gave a much higher level of binding (138 ng/107 sperm) than that found with end‐labelled DNA. This binding was entirely eliminated by DNase I. The separation of live and dead sperm fractions on Percoll gradients revealed that more oligo‐labelled λ Hind III DNA was found to be associated with the dead sperm fraction (31.2 ng/107 sperm) rather than the live sperm fraction (2.7 ng/107 sperm). Analysis of supravital stained, light microscopic autoradiographs confirmed that oligo‐labelled λ Hind III DNA bound to dead sperm in the post‐acrosomal region of the sperm head although other minor distribution patterns were observed.  相似文献   
164.
Identification of the select agent Burkholderia pseudomallei in macaques imported into the United States is rare. A purpose-bred, 4.5-y-old pigtail macaque (Macaca nemestrina) imported from Southeast Asia was received from a commercial vendor at our facility in March 2012. After the initial acclimation period of 5 to 7 d, physical examination of the macaque revealed a subcutaneous abscess that surrounded the right stifle joint. The wound was treated and resolved over 3 mo. In August 2012, 2 mo after the stifle joint wound resolved, the macaque exhibited neurologic clinical signs. Postmortem microbiologic analysis revealed that the macaque was infected with B. pseudomallei. This case report describes the clinical evaluation of a B. pseudomallei-infected macaque, management and care of the potentially exposed colony of animals, and protocols established for the animal care staff that worked with the infected macaque and potentially exposed colony. This article also provides relevant information on addressing matters related to regulatory issues and risk management of potentially exposed animals and animal care staff.Abbreviations: CDC, Centers for Disease Control and Prevention; IHA, indirect hemagglutination assay; PEP, postexposure prophylacticBurkholderia pseudomallei, formerly known as Pseudomonas pseudomallei, is a gram-negative, aerobic, bipolar, motile, rod-shaped bacterium. B. pseudomallei infections (melioidosis) can be severe and even fatal in both humans and animals. This environmental saprophyte is endemic to Southeast Asia and northern Australia, but it has also been found in other tropical and subtropical areas of the world.7,22,32,42 The bacterium is usually found in soil and water in endemic areas and is transmitted to humans and animals primarily through percutaneous inoculation, ingestion, or inhalation of a contaminated source.8, 22,28,32,42 Human-to-human, animal-to-animal, and animal-to-human spread are rare.8,32 In December 2012, the National Select Agent Registry designated B. pseudomallei as a Tier 1 overlap select agent.39 Organisms classified as Tier 1 agents present the highest risk of deliberate misuse, with the most significant potential for mass casualties or devastating effects to the economy, critical infrastructure, or public confidence. Select agents with this status have the potential to pose a severe threat to human and animal health or safety or the ability to be used as a biologic weapon.39Melioidosis in humans can be challenging to diagnose and treat because the organism can remain latent for years and is resistant to many antibiotics.12,37,41 B. pseudomallei can survive in phagocytic cells, a phenomenon that may be associated with latent infections.19,38 The incubation period in naturally infected animals ranges from 1 d to many years, but symptoms typically appear 2 to 4 wk after exposure.13,17,35,38 Disease generally presents in 1 of 2 forms: localized infection or septicemia.22 Multiple methods are used to diagnose melioidosis, including immunofluorescence, serology, and PCR analysis, but isolation of the bacteria from blood, urine, sputum, throat swabs, abscesses, skin, or tissue lesions remains the ‘gold standard.’9,22,40,42 The prognosis varies based on presentation, time to diagnosis, initiation of appropriate antimicrobial treatment, and underlying comorbidities.7,28,42 Currently, there is no licensed vaccine to prevent melioidosis.There are several published reports of naturally occurring melioidosis in a variety of nonhuman primates (NHP; 2,10,13,17,25,30,31,35 The first reported case of melioidosis in monkeys was recorded in 1932, and the first published case in a macaque species was in 1966.30 In the United States, there have only been 7 documented cases of NHP with B. pseudomallei infection.2,13,17 All of these cases occurred prior to the classification of B. pseudomallei as a select agent. Clinical signs in NHP range from subclinical or subacute illness to acute septicemia, localized infection, and chronic infection. NHP with melioidosis can be asymptomatic or exhibit clinical signs such as anorexia, wasting, purulent drainage, subcutaneous abscesses, and other soft tissue lesions. Lymphadenitis, lameness, osteomyelitis, paralysis and other CNS signs have also been reported.2,7,10,22,28,32 In comparison, human''s clinical signs range from abscesses, skin ulceration, fever, headache, joint pain, and muscle tenderness to abdominal pain, anorexia, respiratory distress, seizures, and septicemia.7,9,21,22

Table 1.

Summary of reported cases of naturally occurring Burkholderia pseudomalleiinfections in nonhuman primates
CountryaImported fromDate reportedSpeciesReference
AustraliaBorneo1963Pongo sp.36
BruneiUnknown1982Orangutan (Pongo pygmaeus)33
France1976Hamlyn monkey (Cercopithecus hamlyni) Patas monkey (Erythrocebus patas)11
Great BritainPhilippines and Indonesia1992Cynomolgus monkey (Macaca fascicularis)10
38
MalaysiaUnknown1966Macaca spp.30
Unknown1968Spider monkey (Brachytelis arachnoides) Lar gibbon (Hylobates lar)20
Unknown1969Pig-tailed macaque (Macaca nemestrina)35
Unknown1984Banded leaf monkey (Presbytis melalophos)25
SingaporeUnknown1995Gorillas, gibbon, mandrill, chimpanzee43
ThailandUnknown2012Monkey19
United StatesThailand1970Stump-tailed macaque (Macaca arctoides)17
IndiaPig-tailed macaque (Macaca nemestrina)
AfricaRhesus macaque (Macaca mulatta) Chimpanzee (Pan troglodytes)
Unknown1971Chimpanzee (Pan troglodytes)3
Malaysia1981Pig-tailed macaque (Macaca nemestrina)2
Wild-caught, unknown1986Rhesus macaque (Macaca mulatta)13
Indonesia2013Pig-tailed macaque (Macaca nemestrina)Current article
Open in a separate windowaCountry reflects the location where the animal was housed at the time of diagosis.Here we describe a case of melioidosis diagnosed in a pigtail macaque (Macaca nemestrina) imported into the United States from Indonesia and the implications of the detection of a select agent identified in a laboratory research colony. We also discuss the management and care of the exposed colony, zoonotic concerns regarding the animal care staff that worked with the shipment of macaques, effects on research studies, and the procedures involved in reporting a select agent incident.  相似文献   
165.
Ethylene and jasmonate (JA) have powerful effects when plants are challenged by pathogens. The inducible promoter‐regulated expression of the Arabidopsis ethylene receptor mutant ethylene‐insensitive1‐1 (etr1‐1) causes ethylene insensitivity in petunia. To investigate the molecular mechanisms involved in transgenic petunia responses to Botrytis cinerea related to the ethylene and JA pathways, etr1‐1‐expressing petunia plants were inoculated with Botrytis cinerea. The induced expression of etr1‐1 by a chemical inducer dexamethasone resulted in retarded senescence and reduced disease symptoms on detached leaves and flowers or intact plants. The extent of decreased disease symptoms correlated positively with etr1‐1 expression. The JA pathway, independent of the ethylene pathway, activated petunia ethylene response factor (PhERF) expression and consequent defence‐related gene expression. These results demonstrate that ethylene induced by biotic stress influences senescence, and that JA in combination with delayed senescence by etr1‐1 expression alters tolerance to pathogens.  相似文献   
166.

Background

Virus-induced deterrence to aphid feeding is believed to promote plant virus transmission by encouraging migration of virus-bearing insects away from infected plants. We investigated the effects of infection by an aphid-transmitted virus, cucumber mosaic virus (CMV), on the interaction of Arabidopsis thaliana, one of the natural hosts for CMV, with Myzus persicae (common names: ‘peach-potato aphid’, ‘green peach aphid’).

Methodology/Principal Findings

Infection of Arabidopsis (ecotype Col-0) with CMV strain Fny (Fny-CMV) induced biosynthesis of the aphid feeding-deterrent 4-methoxy-indol-3-yl-methylglucosinolate (4MI3M). 4MI3M inhibited phloem ingestion by aphids and consequently discouraged aphid settling. The CMV 2b protein is a suppressor of antiviral RNA silencing, which has previously been implicated in altering plant-aphid interactions. Its presence in infected hosts enhances the accumulation of CMV and the other four viral proteins. Another viral gene product, the 2a protein (an RNA-dependent RNA polymerase), triggers defensive signaling, leading to increased 4MI3M accumulation. The 2b protein can inhibit ARGONAUTE1 (AGO1), a host factor that both positively-regulates 4MI3M biosynthesis and negatively-regulates accumulation of substance(s) toxic to aphids. However, the 1a replicase protein moderated 2b-mediated inhibition of AGO1, ensuring that aphids were deterred from feeding but not poisoned. The LS strain of CMV did not induce feeding deterrence in Arabidopsis ecotype Col-0.

Conclusions/Significance

Inhibition of AGO1 by the 2b protein could act as a booby trap since this will trigger antibiosis against aphids. However, for Fny-CMV the interplay of three viral proteins (1a, 2a and 2b) appears to balance the need of the virus to inhibit antiviral silencing, while inducing a mild resistance (antixenosis) that is thought to promote transmission. The strain-specific effects of CMV on Arabidopsis-aphid interactions, and differences between the effects of Fny-CMV on this plant and those seen previously in tobacco (inhibition of resistance to aphids) may have important epidemiological consequences.  相似文献   
167.
王华东  曹文杰  张民  付振帅  刘道营  李耀胜 《生物磁学》2013,(25):4929-4931,4912
目的:早期液体复苏对感染性休克患者血流动力学的影响。方法:选取2012年2月-2013年2月我院ICU收治的26例感染性休克患者作为研究对象,随机分为对照组和试验组,各13例。两组患者均采用PICCO监测,并根据早期复苏目标导向(Earlygoaldirectedtherapy,EGDT)进行早期液体复苏治疗。对照组和试验组复苏液分别为林格液和6%羟乙基淀粉130/0.4氯化钠溶液。分别于复苏开始时(Oh)、8h和24h收集患者的血流动力学参数。结果:两组患者CO及PAWP水平均随着时间的延长下降,而CI、CVP及SVR水平均随着时间的增加上升。除对照组CI外,与开始复苏(oh)相比较试验组和对照组的C0、CI、CVP、SVR及PAWP与开始复苏(O小时)相比较均有显著差异(P值均〈0.05)。经重复测量资料的.方差分析进行比较发现,与对照组相比较,试验组CVP和SVR上升水平及PAWP下降水平明显,差异具有统计学意义(P值均〈0.05)。结论:感染性休克患者使用6%羟乙基淀粉130/0.4氯化钠溶液进行复苏,能更好的改善患者的血流动力学指标。  相似文献   
168.
Analysis of serum and plasma proteomes is a common approach for biomarker discovery, and the removal of high‐abundant proteins, such as albumin and immunoglobins, is usually the first step in the analysis. However, albumin binds peptides and proteins, which raises concerns as to how the removal of albumin could impact the outcome of the biomarker study while ignoring the possibility that this could be a biomarker subproteome itself. The first goal of this study was to test a new commercially available affinity capture reagent from Protea Biosciences and to compare the efficiency and reproducibility to four other commercially available albumin depletion methods. The second goal of this study was to determine if there is a highly efficient albumin depletion/isolation system that minimizes sample handling and would be suitable for large numbers of samples. Two of the methods tested (Sigma and ProteaPrep) showed an albumin depletion efficiency of 97% or greater for both serum and cerebrospinal fluid (CSF). Isolated serum and CSF albuminomes from ProteaPrep spin columns were analyzed directly by LC‐MS/MS, identifying 128 serum (45 not previously reported) and 94 CSF albuminome proteins (17 unique to the CSF albuminome). Serum albuminome was also isolated using Vivapure anti‐HSA columns for comparison, identifying 105 proteins, 81 of which overlapped with the ProteaPrep method.  相似文献   
169.
170.
Allele-specific DNA methylation (ASM) is well studied in imprinted domains, but this type of epigenetic asymmetry is actually found more commonly at non-imprinted loci, where the ASM is dictated not by parent-of-origin but instead by the local haplotype. We identified loci with strong ASM in human tissues from methylation-sensitive SNP array data. Two index regions (bisulfite PCR amplicons), one between the C3orf27 and RPN1 genes in chromosome band 3q21 and the other near the VTRNA2-1 vault RNA in band 5q31, proved to be new examples of imprinted DMRs (maternal alleles methylated) while a third, between STEAP3 and C2orf76 in chromosome band 2q14, showed non-imprinted haplotype-dependent ASM. Using long-read bisulfite sequencing (bis-seq) in 8 human tissues we found that in all 3 domains the ASM is restricted to single differentially methylated regions (DMRs), each less than 2kb. The ASM in the C3orf27-RPN1 intergenic region was placenta-specific and associated with allele-specific expression of a long non-coding RNA. Strikingly, the discrete DMRs in all 3 regions overlap with binding sites for the insulator protein CTCF, which we found selectively bound to the unmethylated allele of the STEAP3-C2orf76 DMR. Methylation mapping in two additional genes with non-imprinted haplotype-dependent ASM, ELK3 and CYP2A7, showed that the CYP2A7 DMR also overlaps a CTCF site. Thus, two features of imprinted domains, highly localized DMRs and allele-specific insulator occupancy by CTCF, can also be found in chromosomal domains with non-imprinted ASM. Arguing for biological importance, our analysis of published whole genome bis-seq data from hES cells revealed multiple genome-wide association study (GWAS) peaks near CTCF binding sites with ASM.  相似文献   
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