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Overwintering is a challenging period in the life of temperate insects. A limited energy budget characteristic of this period can result in reduced investment in immune system. Here, we investigated selected physiological and immunological parameters in laboratory‐reared and field‐collected harlequin ladybirds (Harmonia axyridis). For laboratory‐reared beetles, we focused on the effects of winter temperature regime (cold, average, or warm winter) on total haemocyte concentration aiming to investigate potential effects of ongoing climate change on immune system in overwintering insects. We recorded strong reduction in haemocyte concentration during winter; however, there were only limited effects of winter temperature regime on changes in haemocyte concentration in the course of overwintering. For field‐collected beetles, we measured additional parameters, specifically: total protein concentration, antimicrobial activity against Escherichia coli, and haemocyte concentration before and after overwintering. The field experiment did not investigate effects of winter temperature, but focused on changes in inducibility of insect immune system during overwintering, that is, measured parameters were compared between naïve beetles and those challenged by Escherichia coli. Haemocyte concentration decreased during overwintering, but only in individuals challenged by Escherichia coli. Prior to overwintering, the challenged beetles had a significantly higher haemocyte concentration compared to naïve beetles, whereas no difference was observed after overwintering. A similar pattern was observed also for antimicrobial activity against Escherichia coli as challenged beetles outperformed naïve beetles before overwintering, but not after winter. In both sexes, total protein concentration increased in the course of overwintering, but females had a significantly higher total protein concentration in their hemolymph compared to males. In general, our results revealed that insect’s ability to respond to an immune challenge is significantly reduced in the course of overwintering.  相似文献   
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We report the purification and characterization of a nitrilase (E.C. 3.5.5.1) (Nit11764) essential for the assimilation of cyanide as the sole nitrogen source by the cyanotroph, Pseudomonas fluorescens NCIMB 11764. Nit11764, is a member of a family of homologous proteins (nitrile_sll0784) for which the genes typically reside in a conserved seven-gene cluster known as Nit1C. The physical properties and substrate specificity of Nit11764 resemble those of Nit6803, the current reference protein for the family, and the only true nitrilase that has been crystallized. The substrate binding pocket of the two enzymes places the substrate in direct proximity to the active site nucleophile (C160) and conserved catalytic triad (Glu44, Lys126). The two enzymes exhibit a similar substrate profile, however, for Nit11764, cinnamonitrile, was found to be an even better substrate than fumaronitrile the best substrate previously identified for Nit6803. A higher affinity for cinnamonitrile (Km 1.27 mM) compared to fumaronitrile (Km 8.57 mM) is consistent with docking studies predicting a more favorable interaction with hydrophobic residues lining the binding pocket. By comparison, 3,4-dimethoxycinnamonitrile was a poorer substrate the substituted methoxyl groups apparently hindering entry into the binding pocket. in situ 1H NMR studies revealed that only one of the two nitrile substituents in the dinitrile, fumaronitrile, was attacked yielding trans-3-cyanoacrylate (plus ammonia) as a product. The essentiality of Nit11764 for cyanotrophy remains uncertain given that cyanide itself is a poor substrate and the catalytic efficiencies for even the best of nitrile substrates (~5 × 103 M?1 s?1) is less than stellar.  相似文献   
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The purpose of this study was to examine undergraduate music education and performance alumni's career path, retrospective institutional satisfaction, and financial status. Data for this study were drawn from respondents from the 2010 administration of the nationwide, multi-institutional survey conducted by the Strategic National Arts Alumni Project (SNAAP). Regarding career path, nearly half of the music performance degree graduates reported performing as their current job, and slightly more than half of the music education degree graduates reported working in K–12 schools. Participants were generally satisfied with their institutional experiences, although relatively low levels of satisfaction were reported for networking and career advising services. The respondents reported being most satisfied with aspects of their current jobs that reflected the intrinsic benefits of contributing to a greater good, satisfying personal interests and values, and opportunities to be creative. The majority of the sample reported accruing student loan debt ranging between $10,000 and $30,000; however, no significant differences were found between groups, and 40 percent of the participants reported having accrued no debt at all. The reported annual income of the participants varied significantly, with music educators reporting higher earnings than performers.  相似文献   
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Business‐to‐business (B2B) electronics account for a significant volume of the electrical and electronic equipment (EEE) put on the market. Very little B2B waste electrical and electronic equipment (WEEE) is reported as collected in the European Union (EU) in compliance with the WEEE Directive, which uses the policy principle of extended producer responsibility (EPR) to ensure that WEEE is managed correctly. This presents a barrier to parties looking for access to the waste. Company practice dictates the channels into which B2B WEEE flows following primary use. This article presents a study that engaged with company actors directly to get a better understanding of business information technology (IT) EEE asset management. Data were collected to determine the barriers current practice could present to the collection of B2B IT EEE at end of life and the implications of these for the development of policies and strategies for EPR. A questionnaire was developed and data were gathered from organizations in three EU countries—the United Kingdom, Germany, and France—stratified by size. Some notable findings were that there are several routes by which end‐of‐life B2B WEEE can flow. The recycling and refurbishment of B2B IT units at end of use was shown to be commonplace, but it is likely that these units enter streams where they are not reported. The actors disposing of their units did not have information on the management or disposition of these streams. It is concluded that to achieve the goals of EPR for B2B IT WEEE, the networks and the operational practices of these streams need to be better understood when developing strategies and policies.  相似文献   
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Introduction

Gout is a common arthritis that occurs particularly in patients who frequently have associated comorbidities that limit the use of conventional therapies. The main mechanism of crystal-induced inflammation is interleukin-1 production by activation of the inflammasome. We aimed to evaluate the efficacy and tolerance of anakinra in gouty patients.

Methods

We conducted a multicenter retrospective review of patients receiving anakinra for gouty arthritis. We reviewed the response to treatment, adverse events and relapses.

Results

We examined data for 40 gouty patients (32 men; mean age 60.0 ± 13.9 years) receiving anakinra. Mean disease duration was 8.7 ± 8.7 years. All patients showed contraindications to and/or failure of at least two conventional therapies. Most (36; 90%) demonstrated good response to anakinra. Median pain on a 100-mm visual analog scale was rapidly decreased (73.5 (70.0 to 80.0) to 25.0 (20.0 to 32.5) mm, P <0.0001), as was median C-reactive protein (CRP) level (130.5 (55.8 to 238.8) to 16.0 (5.0 to 29.5) mg/l, P <0.0001). After a median follow-up of 7.0 (2.0 to 13.0) months, relapse occurred in 13 patients after a median delay of 15.0 (10.0 to 70.0) days. Seven infectious events, mainly with long-term use of anakinra, were noted.

Conclusions

Anakinra may be efficient in gouty arthritis, is relatively well tolerated with short-term use, and could be a relevant option in managing gouty arthritis when conventional therapies are ineffective or contraindicated. Its long-term use could be limited by infectious complications.  相似文献   
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Tumors that formed in newborn nude mice that were inoculated with 107 Madin–Darby canine kidney (MDCK) cells were associated with a failure-to-thrive (FTT) syndrome consisting of growth retardation, lethargy, weakness, and dehydration. Scoliosis developed in 41% of affected pups. Pups were symptomatic by week 2; severely affected pups became moribund and required euthanasia within 3 to 4 wk. Mice with FTT were classified into categories of mild, moderate, and severe disease by comparing their weight with that of age-matched normal nude mice. The MDCK-induced tumors were adenocarcinomas that invaded adjacent muscle, connective tissue, and bone; 6 of the 26 pups examined had lung metastases. The induction of FTT did not correlate with cell-line aggressiveness as estimated by histopathology or the efficiency of tumor formation (tumor-forming dose 50% endpoint range = 102.8 to 107.5); however, tumor invasion of the paravertebral muscles likely contributed to the scoliosis noted. In contrast to the effect of MDCK cells, tumor formation observed in newborn mice inoculated with highly tumorigenic, human-tumor–derived cell lines was not associated with FTT development. We suggest that tumor formation and FTT are characteristics of these MDCK cell inocula and that FTT represents a new syndrome that may be similar to the cachexia that develops in humans with cancer or other diseases.Abbreviations: FTT, failure-to-thrive; MDCK, Madin–Darby canine kidney; TPD50, tumor-producing dose log10 50% endpointThe Madin–Darby canine kidney (MDCK) cell line was established in 1958 from the kidney of a cocker spaniel.6,16 Since 1962, this cell line has been an important reagent for the isolation and study of influenza viruses8,22,31 and, more recently, for the development and manufacture of influenza virus vaccines.3,7,19 MDCK cells are polarized, epithelial cells that exhibit properties of renal tubular epithelium and have been used as in vitro models to evaluate renal tubular functions.24,36 Due to their apparent lack of expression of a tumorigenic phenotype in rodents,25 MDCK cells have also been used to study neoplastic processes including epithelial-to-mesenchymal transition23,27,28 and to assess the effects of viral oncogenes and chemical carcinogens on their phenotype.13,32The results of studies that evaluate the ability of MDCK cells to form tumors in vivo have varied. Early studies found that these cells could produce tumors in chicken embryos but not in mature BALB/c nude mice.14 In contrast, MDCK cells formed progressively growing adenocarcinomas in newborn BALB/c nude mice, but tumor growth ceased as the pups approached maturity.25 More recently, 2 different sublines of MDCK cells developed by independent groups were shown to be tumorigenic in athymic nude mice; but the incidence of tumor formation did not correlate with cell dose.33-35As an initial approach to the study of neoplastic development in cells in culture, we evaluated the ability of MDCK cells to form tumors in athymic nude mice. We previously described the tumor-forming capacity of MDCK cells from different lots obtained from ATCC.21 That study revealed that MDCK cells from each of these lots formed tumors efficiently in adult and newborn nude mice, but the capacity of the cells to form tumors differed from lot to lot. During the initial experiments on MDCK cell tumor-forming efficiency in newborn nude mice, we observed what appeared to be a syndrome whose symptoms included tumor formation and disrupted growth leading to a failure-to-thrive (FTT) condition manifested by morbidity that required euthanasia of those pups most severely affected. During the study on the development of FTT, we found that the FTT syndrome occurred in newborn nude mice inoculated with 3 different sublines of MDCK cells. The current report describes an FTT syndrome associated with the formation of tumors by 107 MDCK cells in newborn, athymic, nude mice.  相似文献   
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