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131.
The objective of this study was to determine the prevalence, mutual associations, clinical manifestations, and diagnoses associated with serum autoantibodies, as detected using recently available immunoassays, in patients with autoimmune myositis (AIM). Sera and clinical data were collected from 100 patients with AIM followed longitudinally. Sera were screened cross-sectionally for 21 autoantibodies by multiplex addressable laser bead immunoassay, line blot immunoassay, immunoprecipitation of in vitro translated recombinant protein, protein A assisted immunoprecipitation, and enzyme-linked immunosorbent assay. Diagnoses were determined using the Bohan and Peter classification as well as recently proposed classifications. Relationships between autoantibodies and clinical manifestations were analyzed by multiple logistic regression. One or more autoantibodies encompassing 19 specificities were present in 80% of the patients. The most common autoantibodies were anti-Ro52 (30% of patients), anti-Ku (23%), anti-synthetases (22%), anti-U1RNP (15%), and anti-fibrillarin (14%). In the presence of autoantibodies to Ku, synthetases, U1RNP, fibrillarin, PM-Scl, or scleroderma autoantigens, at least one more autoantibody was detected in the majority of sera and at least two more autoantibodies in over one-third of sera. The largest number of concurrent autoantibodies was six autoantibodies. Overall, 44 distinct combinations of autoantibodies were counted. Most autoantibodies were unrestricted to any AIM diagnostic category. Distinct clinical syndromes and therapeutic responses were associated with anti-Jo-1, anti-fibrillarin, anti-U1RNP, anti-Ro, anti-Ro52, and autoantibodies to scleroderma autoantigens. We conclude that a significant proportion of AIM patients are characterized by complex associations of autoantibodies. Certain myositis autoantibodies are markers for distinct overlap syndromes and predict therapeutic outcomes. The ultimate clinical features, disease course, and response to therapy in a given AIM patient may be linked to the particular set of associated autoantibodies. These results provide a rationale for patient profiling and its application to therapeutics, because it cannot be assumed that the B-cell response is the same even in the majority of patients in a given diagnostic category.  相似文献   
132.
In the absence of fire in black spruce-feathermoss stands, a thick forest floor layer dominated by bryophytes and sphagnum accumulates. This layer is associated with wet, cool and nutrient-poor soil conditions conducive to the paludification process and pushing the ecosystem towards an unproductive open black spruce forest. The presence of Populus tremuloides in theses stands may halt this process because this species has a high nutrient cycling rate and a litter that represses moss cover. The main hypothesis of this study is that, despite similar abiotic conditions (slope and drainage), the presence of Populus tremuloides in a stand dominated by Picea mariana affects surface soil nutrient availability, total N, pH as well as the decomposition process. The abundance of Populus tremuloides trees was associated with higher exchangeable cations, cationic exchangeable capacity and pH of the forest floor layer on all sites. A decrease in organic matter thickness with increasing aspen presence was also found on all sites, suggesting that this species affects the decomposition process by the quality of its litter as well as by a general improvement of soil physical and chemical properties. The decomposition rate of a standard substrate as well as in vitro potential net nitrogen mineralization were positively related to Populus tremuloides on only one of the three sites, and non-significant on the other sites. Strong immobilization of added nitrogen during incubation was observed on all sites and was not related to aspen, which suggested that in these stands, the soil microbial community is uniformly and strongly nitrogen limited. The zone of influence of Populus tremuloides was evaluated in areas around the soil sampling plot ranging from 3 to 7 m. The results revealed that this zone varies with soil properties. The results suggest that the presence of Populus tremuloides accelerate nutrient cycling, which could affect stand productivity to some extent.  相似文献   
133.
With rapidly increasing rates of contemporary extinction, predicting extinction vulnerability and identifying how multiple stressors drive non-random species loss have become key challenges in ecology. These assessments are crucial for avoiding the loss of key functional groups that sustain ecosystem processes and services. We developed a novel predictive framework of species extinction vulnerability and applied it to coral reef fishes. Although relatively few coral reef fishes are at risk of global extinction from climate disturbances, a negative convex relationship between fish species locally vulnerable to climate change vs. fisheries exploitation indicates that the entire community is vulnerable on the many reefs where both stressors co-occur. Fishes involved in maintaining key ecosystem functions are more at risk from fishing than climate disturbances. This finding is encouraging as local and regional commitment to fisheries management action can maintain reef ecosystem functions pending progress towards the more complex global problem of stabilizing the climate.  相似文献   
134.
Family-group names in Coleoptera (Insecta)   总被引:1,自引:0,他引:1  
We synthesize data on all known extant and fossil Coleoptera family-group names for the first time. A catalogue of 4887 family-group names (124 fossil, 4763 extant) based on 4707 distinct genera in Coleoptera is given. A total of 4492 names are available, 183 of which are permanently invalid because they are based on a preoccupied or a suppressed type genus. Names are listed in a classification framework. We recognize as valid 24 superfamilies, 211 families, 541 subfamilies, 1663 tribes and 740 subtribes. For each name, the original spelling, author, year of publication, page number, correct stem and type genus are included. The original spelling and availability of each name were checked from primary literature. A list of necessary changes due to Priority and Homonymy problems, and actions taken, is given. Current usage of names was conserved, whenever possible, to promote stability of the classification.New synonymies (family-group names followed by genus-group names): Agronomina Gistel, 1848 syn. nov. of Amarina Zimmermann, 1832 (Carabidae), Hylepnigalioini Gistel, 1856 syn. nov. of Melandryini Leach, 1815 (Melandryidae), Polycystophoridae Gistel, 1856 syn. nov. of Malachiinae Fleming, 1821 (Melyridae), Sclerasteinae Gistel, 1856 syn. nov. of Ptilininae Shuckard, 1839 (Ptinidae), Phloeonomini Ádám, 2001 syn. nov. of Omaliini MacLeay, 1825 (Staphylinidae), Sepedophilini Ádám, 2001 syn. nov. of Tachyporini MacLeay, 1825 (Staphylinidae), Phibalini Gistel, 1856 syn. nov. of Cteniopodini Solier, 1835 (Tenebrionidae); Agronoma Gistel 1848 (type species Carabus familiaris Duftschmid, 1812, designated herein) syn. nov. of Amara Bonelli, 1810 (Carabidae), Hylepnigalio Gistel, 1856 (type species Chrysomela caraboides Linnaeus, 1760, by monotypy) syn. nov. of Melandrya Fabricius, 1801 (Melandryidae), Polycystophorus Gistel, 1856 (type species Cantharis aeneus Linnaeus, 1758, designated herein) syn. nov. of Malachius Fabricius, 1775 (Melyridae), Sclerastes Gistel, 1856 (type species Ptilinus costatus Gyllenhal, 1827, designated herein) syn. nov. of Ptilinus Geoffroy, 1762 (Ptinidae), Paniscus Gistel, 1848 (type species Scarabaeus fasciatus Linnaeus, 1758, designated herein) syn. nov. of Trichius Fabricius, 1775 (Scarabaeidae), Phibalus Gistel, 1856 (type species Chrysomela pubescens Linnaeus, 1758, by monotypy) syn. nov. of Omophlus Dejean, 1834 (Tenebrionidae). The following new replacement name is proposed: Gompeliina Bouchard, 2011 nom. nov. for Olotelina Báguena Corella, 1948 (Aderidae).Reversal of Precedence (Article 23.9) is used to conserve usage of the following names (family-group names followed by genus-group names): Perigonini Horn, 1881 nom. protectum over Trechicini Bates, 1873 nom. oblitum (Carabidae), Anisodactylina Lacordaire, 1854 nom. protectum over Eurytrichina LeConte, 1848 nom. oblitum (Carabidae), Smicronychini Seidlitz, 1891 nom. protectum over Desmorini LeConte, 1876 nom. oblitum (Curculionidae), Bagoinae Thomson, 1859 nom. protectum over Lyprinae Gistel 1848 nom. oblitum (Curculionidae), Aterpina Lacordaire, 1863 nom. protectum over Heliomenina Gistel, 1848 nom. oblitum (Curculionidae), Naupactini Gistel, 1848 nom. protectum over Iphiini Schönherr, 1823 nom. oblitum (Curculionidae), Cleonini Schönherr, 1826 nom. protectum over Geomorini Schönherr, 1823 nom. oblitum (Curculionidae), Magdalidini Pascoe, 1870 nom. protectum over Scardamyctini Gistel, 1848 nom. oblitum (Curculionidae), Agrypninae/-ini Candèze, 1857 nom. protecta over Adelocerinae/-ini Gistel, 1848 nom. oblita and Pangaurinae/-ini Gistel, 1856 nom. oblita (Elateridae), Prosternini Gistel, 1856 nom. protectum over Diacanthini Gistel, 1848 nom. oblitum (Elateridae), Calopodinae Costa, 1852 nom. protectum over Sparedrinae Gistel, 1848 nom. oblitum (Oedemeridae), Adesmiini Lacordaire, 1859 nom. protectum over Macropodini Agassiz, 1846 nom. oblitum (Tenebrionidae), Bolitophagini Kirby, 1837 nom. protectum over Eledonini Billberg, 1820 nom. oblitum (Tenebrionidae), Throscidae Laporte, 1840 nom. protectum over Stereolidae Rafinesque, 1815 nom. oblitum (Throscidae) and Lophocaterini Crowson, 1964 over Lycoptini Casey, 1890 nom. oblitum (Trogossitidae); Monotoma Herbst, 1799 nom. protectum over Monotoma Panzer, 1792 nom. oblitum (Monotomidae); Pediacus Shuckard, 1839 nom. protectum over Biophloeus Dejean, 1835 nom. oblitum (Cucujidae), Pachypus Dejean, 1821 nom. protectum over Pachypus Billberg, 1820 nom. oblitum (Scarabaeidae), Sparrmannia Laporte, 1840 nom. protectum over Leocaeta Dejean, 1833 nom. oblitum and Cephalotrichia Hope, 1837 nom. oblitum (Scarabaeidae).  相似文献   
135.
136.
Metabolites of the potent DP antagonist, MK-0524, were generated using in vitro systems including hepatic microsomes and hepatocytes. Four metabolites (two hydroxylated diastereomers, a ketone and an acyl glucuronide) were characterized by LC-MS/MS and 1H NMR. Larger quantities of these metabolites were prepared by either organic synthesis or biosynthetically to be used as standards in other studies. The propensity for covalent binding was assessed and was found to be acceptable (<50 pmol-equiv/mg protein).  相似文献   
137.
Monocyte chemotactic protein-1 (MCP-1) recruits activated phagocytes to the site of tissue injury. Interferon-gamma (IFN-gamma) present in the microenvironment of glomerulus acts on mesangial cells to induce local production of MCP-1. The mechanism by which IFN-gamma stimulates expression of MCP-1 is not clear. We therefore examined the role of PI 3 kinase signaling in regulating the IFN-gamma-induced MCP-1 expression in mesangial cells. Blocking PI 3 kinase activity with Ly294002 attenuated IFN-gamma-induced MCP-1 protein and mRNA expression. IFN-gamma increased Akt kinase activity in a PI 3 kinase-dependent manner. Expression of dominant negative Akt kinase inhibited serine phosphorylation of STAT1alpha, without any effect on its tyrosine phosphorylation, and decreased IFN-gamma-induced expression of MCP-1. These data for the first time indicate a role for PI 3 kinase-dependent Akt kinase in MCP-1 expression. We have recently shown that along with Akt, PKCepsilon is a downstream target of PI 3 kinase in IFN-gamma signaling. Similar to dominant negative Akt kinase, dominant negative PKCepsilon also inhibited serine phosphorylation of STAT1alpha without any effect on tyrosine phosphorylation. Dominant negative PKCepsilon also abrogated MAPK activity, resulting in decrease in IFN-gamma-induced MCP-1 expression. Furthermore, Akt and PKCepsilon are present together in a signaling complex. IFN-gamma had no effect on this complex formation, but did increase PKCepsilon-associated Akt kinase activity. PKCepsilon did not regulate IFN-gamma-induced Akt kinase. Finally, expression of dominant negative Akt kinase blocked IFN-gamma-stimulated MAPK activation. These data provide the first evidence that PI 3 kinase-dependent Akt and PKCepsilon activation independently regulate MAPK activity and serine phosphorylation of STAT1alpha to increase expression of MCP-1.  相似文献   
138.
We studied in the rat the effects of the drug etretinate (Tigason), given at three doses 3, 10, and 30 mg/kg body wt for 1 mo, on the concentrations of Na, K, Ca, Mg, Fe, S, P, Cu, and Zn in the plasma, brain, thymus, heart, liver, lung, kidney, testicle, muscle, and bone. The elements were simultaneously determined in tissues after nitric acid dissolution by inductively coupled plasma emission spectrometry using a JY 48 instrument. At the dose of 3 mg/kg, etretinate did not induce any statistically significant modifications of the element distribution. At the dose of 10 mg/kg, the main observed modifications were in plasma an increase of copper (+38%) and a decrease of zinc (-25%). At the highest dose of 30 mg/kg, some variations of the concentrations of elements in tissues were observed. But, on no account did retinoids induce an alteration of the mineral composition of bone, despite obvious macroscopic bone alterations.  相似文献   
139.
The orientation of the mitotic spindle plays a key role in determining whether a polarized cell will divide symmetrically or asymmetrically. In most cell types, cytoplasmic dynein plays a critical role in spindle orientation. However, how dynein directs opposite spindle poles toward distinct and predetermined cell ends is poorly understood. Here, we show that dynein distributes preferentially to the spindle pole bodies (SPB) and astral microtubules (MTs) proximal to the bud in metaphase yeast cells. Dynein asymmetry depended on the bud neck kinases Elm1, Hsl1, and Gin4, on the spindle pole components Cnm67 and Cdk1, and on the B-type cyclins Clb1 and Clb2. Furthermore, phenotypic and genetic studies both indicated that dynein is unable to orient the spindle when it localizes to both poles and associated microtubules. Together, our data indicate that proper orientation of the spindle requires dynein to act on a single spindle pole.  相似文献   
140.
TP53 and FGFR3 mutations are the most common mutations in bladder cancers. FGFR3 mutations are most frequent in low-grade low-stage tumours, whereas TP53 mutations are most frequent in high-grade high-stage tumours. Several studies have reported FGFR3 and TP53 mutations to be mutually exclusive events, whereas others have reported them to be independent. We carried out a meta-analysis of published findings for FGFR3 and TP53 mutations in bladder cancer (535 tumours, 6 publications) and additional unpublished data for 382 tumours. TP53 and FGFR3 mutations were not independent events for all tumours considered together (OR = 0.25 [0.18–0.37], p = 0.0001) or for pT1 tumours alone (OR = 0.47 [0.28–0.79], p = 0.0009). However, if the analysis was restricted to pTa tumours or to muscle-invasive tumours alone, FGFR3 and TP53 mutations were independent events (OR = 0.56 [0.23–1.36] (p = 0.12) and OR = 0.99 [0.37–2.7] (p = 0.35), respectively). After stratification of the tumours by stage and grade, no dependence was detected in the five tumour groups considered (pTaG1 and pTaG2 together, pTaG3, pT1G2, pT1G3, pT2-4). These differences in findings can be attributed to the putative existence of two different pathways of tumour progression in bladder cancer: the CIS pathway, in which FGFR3 mutations are rare, and the Ta pathway, in which FGFR3 mutations are frequent. TP53 mutations occur at the earliest stage of the CIS pathway, whereas they occur would much later in the Ta pathway, at the T1G3 or muscle-invasive stage.  相似文献   
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