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101.
Rheumatoid arthritis (RA) is associated with a similar cardiovascular risk to that in diabetes, and therefore cardiovascular risk management (CV-RM) - that is, identification and treatment of cardiovascular risk factors (CRFs) - is mandatory. However, whether and to what extent this is done in daily clinical practice is unknown. In a retrospective cohort investigation, CV-RM was therefore compared between rheumatologists and primary care physicians (PCPs). Remarkably, CRFs in RA were less frequently identified and managed by rheumatologists in comparison with PCPs. In addition, PCPs assessed CRFs less frequently in RA than in diabetes. Obviously, there is a clear need for improvement of CV-RM in RA and this should be a joint effort from the rheumatologist and the PCP.Patients with rheumatoid arthritis (RA) have an increased cardiovascular (CV) risk that appears similar to that in diabetes. This observation highlights the significant CV burden in RA. In 1999, the American Diabetes Association and the American Heart Association published a statement for prevention of CV disease in diabetes. Since then, the CV risk in diabetes has been substantially lower than in earlier decades. Given the increased CV risk in RA, screening, identification of cardiovascular risk factors (CRFs) and cardiovascular risk management (CV-RM) are also highly needed as recommended by the European League Against Rheumatism (EULAR). The increased risk in RA is attributed to systemic inflammation as well as increased prevalence of CRFs. Hence, we should aim for tight disease control and control of CRFs.Presently unknown is whether and to what extent CV-RM is translated into clinical practice. In a retrospective cohort-comprising 251 patients with RA, 251 patients with diabetes, and 251 general population individuals-Desai and colleagues therefore investigated the identification and management of CRFs by rheumatologists and primary care physicians (PCPs) [1]. RA patients had to be registered at the University of Michigan Health System for at least 12 months between June 2007 and April 2012 and had been evaluated both by their rheumatologist as well as the PCP. CRFs of interest were smoking, exercise, weight, blood pressure, lipid profile, and fasting blood glucose.In RA, PCPs identified and managed most CRFs more frequently than rheumatologists. Secondly, identification of CRFs by rheumatologists in RA patients with elevated C-reactive protein levels was not different as compared with those with normal C-reactive protein levels. A third important observation was that PCPs identified and managed CRFs more frequently in patients with diabetes, followed by general population individuals and least often in RA patients. These striking results raise several issues.First, it is hard to believe that the largely absent CV-RM by rheumatologists is explained by under-recognition because the increased CV risk in RA must presently be well known among rheumatologists. A large amount of literature on this topic has been published over the last decade. Additionally, the necessity to screen, identify, and manage CRFs is incorporated into training programmes for rheumatology residents [2]. Against this background, it is important to realise that there is a lag time between the publication of the EULAR guideline and its actual implementation (that is, the guideline was published in 2010 [3] while the current study started in 2007). In other words, CV-RM in today''s clinical practice might have been improved, but not yet recognised.Second, that the CV risk in RA is related to the inflammatory burden is well known. Nevertheless, the present study did not indicate that there is more attention for CV-RM by rheumatologists in patients with a higher inflammatory load.Third, undertreatment of the increased CV risk in RA by PCPs might be explained by under-recognition because CRFs were assessed more frequently in diabetes in comparison with RA.The EULAR guidelines recommend screening and identification of CRFs in all RA patients, and, if indicated according to CV risk-prediction charts, adequate management. As accurate assessment of CV risk depends on RA characteristics, the EULAR favoured individualising risk assessment. Hence, a risk multiplication factor of 1.5 should be used in the presence of two of the following criteria: disease duration >10 years, rheumatoid factor, and/or anti-cyclic citrullinated peptide positivity or the presence of extra-articular manifestations. However, alternative approaches have been suggested - for example, increasing the age of an RA patient by 10 years to obtain a more precise CV risk estimate or to use other risk scores. Perhaps this lack of an RA-specific CV risk-prediction model hampers CV-RM implementation. Obviously, this discussion can only be solved by developing a RA-specific CV risk-prediction model, but this will take several years to complete.One may obviously argue that, due to its retrospective design, the strength of the conclusions of Desai and colleagues may be limited; however, they are in line with other recently published literature and thus confirm extending evidence that CV-RM is poorly conducted in RA, both by rheumatologists and PCPs. Another argument against CV-RM in RA is that we should wait until trials have been conducted that demonstrate the efficacy of statins and antihypertensive agents in RA. However, it will be (many) years before specific risk models are available and withholding cardiopreventive drugs that are very likely to work also in our high-risk population is unethical. Moreover, it is important to realise that, due to the decreased incidence of CV events in the last decades, CV prevention trials are nowadays very difficult to conduct. For instance, the TRACE-RA study [4] - a large placebo-controlled double-blind primary CV prevention trial in RA with atorvastatin - was stopped prematurely owing to the very low number of CV events that occurred.Altogether, the study from Desai and colleagues provides three important clues for improvement of CV-RM in RA. First, more education is urgently needed for both rheumatologists and PCPs. Second, it is important to realise that the contribution of higher prevalence CRFs in RA is one side of the coin, but the other side is effective suppression of the inflammation. The latter is a clear task for the rheumatologist. Third, CV care of a RA patient should be a joint effort by the rheumatologist and the PCP, and they should collaborate and agree on who performs the screening, identification, and, if required, management of CRFs.  相似文献   
102.
Summary

The decline with age of mictic female susceptibility to fertilization and male capacity for fertilization is characterized for the rotifer Brachionus plicatilis. All mictic females were susceptible to fertilization until age 4 hr. Susceptibility then declined non-linearly according to the quadratic equation Y = 140.6—14.3X + 0.36X 2. By age 24 hr, sexual females no longer could be fertilized. Only 83% of newborn males were capable of fertilization. This level of fertility held until age 8 hr, then declined linearly. The age when 50% of individuals were no longer fertile was termed the length of fertilizability 50(LF50) and is 7.9 hr (16.7% of lifespan) and 18.8 hr (26.1% of lifespan) for females and males, respectively. Newborn males had an average of 30.1 ± 1.40 motile sperm. Males transferred a mean of 2.3 motile sperm into the pseudocoelom of females on each insemination. Sperm inseminated per copulation closely corresponds to the mean number of resting cysts produced by fertilized females. It is not likely that resting cyst production is limited by sperm availability.  相似文献   
103.
Dage  JL; Ackermann  BL; Halsall  HB 《Glycobiology》1998,8(8):755-760
A simple, fast and sensitive method was developed to verify the presence of the sialyl Lewis(x) antigen on an N-linked glycoprotein. High performance liquid chromatography-electrospray mass spectrometry (HPLC-ESI/MS) was used to identify which of the five N-linked glycosylation sites of human plasma alpha1-acid-glycoprotein (orosomucoid, OMD) contain the sialyl Lewis(x) antigen. OMD was digested with proteolytic enzymes and analyzed by reversed phase chromatography coupled with on-line ESI/MS. A tandem mass spectrometry experiment was designed to detect the presence of the sialyl Lewis(x) antigen based on the observation of an 803 mass to charge ratio ( m/z ) ion produced in the intermediate pressure region of the ESI interface. The ESI/MS signal at m/z 803 is consistent with an oxonium ion for a glycan structure containing NeuAc, Gal, GlcNAc, and Fuc. The identity of the m/z 803 ion was confirmed by ESI/MS/MS analysis of the m/z 803 fragment ion and comparison with a sialyl Lewis(x) standard. The stereochemistry and linkage positions were assigned using previous NMR analysis but could be determined with permethylation analysis if necessary. The analysis of OMD gave a pattern showing signal for the sialyl Lewis(x) antigen coeluting with each of the five N-linked glycopeptides. The ability to monitor sialyl Lewis(x) expression at each of the five sites is of interest in the study of OMD's role in inflammatory diseases.   相似文献   
104.
Leonardite is an oxidized form of lignite carbon, which is obtained from fossilized organic materials. Such materials are used for the extraction of humic acids (HA). The result of the addition of HA of organic origin on soil structure is known; however, the effects of adding HA of Leonardite on soil structure have been scarcely investigated. The objectives of this research were (1) to determine the influence of humic acids derived from Leonardite in increasing the aggregate stability of an Aridisol under greenhouse conditions, and (2) evaluate the morphology of the root xylem during the phenological development of melon plants (Cucumis melo L.). Three treatments of HA solution application to the soil were used: soil without solution application (HA0), and application of HA solution to the soil with pH 6 (HA6) or (HA7). Aggregate stability (As) and bulk density (Da) were evaluated as soil variables. Development and quantification of xylem area were studied on plants. There were significant differences in aggregate stability. Also, there was an increase in the root xylem area, and the best treatment was when AH7 solution was applied. Humic acids derived from Leonardite increased the stability of soil aggregates when plants grew under greenhouse conditions, and fostered the development of xylem conduits during the fruiting stage.  相似文献   
105.
106.
Estimating the rate of evolution of the rate of molecular evolution   总被引:22,自引:13,他引:22  
A simple model for the evolution of the rate of molecular evolution is presented. With a Bayesian approach, this model can serve as the basis for estimating dates of important evolutionary events even in the absence of the assumption of constant rates among evolutionary lineages. The method can be used in conjunction with any of the widely used models for nucleotide substitution or amino acid replacement. It is illustrated by analyzing a data set of rbcL protein sequences.   相似文献   
107.
Iridoviruses of the genus Ranavirus are well known for causing mass mortality events of fish and amphibians with sporadic reports of infection in reptiles. This article describes five instances of Ranavirus infection in chelonians between 2003 and 2005 in Georgia, Florida, New York, and Pennsylvania, USA. Affected species included captive Burmese star tortoises (Geochelone platynota), a free-ranging gopher tortoise (Gopherus polyphemus), free-ranging eastern box turtles (Terrapene carolina carolina), and a Florida box turtle (Terrepene carolina bauri). Evidence for Ranavirus infection was also found in archived material from previously unexplained mass mortality events of eastern box turtles from Georgia in 1991 and from Texas in 1998. Consistent lesions in affected animals included necrotizing stomatitis and/or esophagitis, fibrinous and necrotizing splenitis, and multicentric fibrinoid vasculitis. Intracytoplasmic inclusion bodies were rarely observed in affected tissues. A portion of the major capsid protein (MCP) gene was sequenced from each case in 2003-2005 and found to be identical to each other and to Frog virus 3 (FV3) across 420 base pairs. Ranavirus infections were also documented in sympatric species of amphibians at two locations with infected chelonians. The fragment profiles of HindIII-digested whole genomic DNA of Ranavirus, isolated from a dead Burmese star tortoise and a southern leopard frog (Rana utricularia) found nearby, were similar. The box turtle isolate had a low molecular weight fragment that was not seen in the digestion profiles for the other isolates. These results suggest that certain amphibians and chelonians are infected with a similar virus and that different viruses exist among different chelonians. Amphibians may serve as a reservoir host for susceptible chelonians. This report also demonstrated that significant disease associated with Ranavirus infections are likely more widespread in chelonians than previously suspected.  相似文献   
108.
109.
Cigarette smoke contains nicotine and toxic chemicals and may cause significant neurochemical and anatomical brain changes. Voxel-based morphometry studies have examined the effects of smoking on the brain by comparing gray matter volume (GMV) in nicotine dependent individuals (NDs) to nonsmoking individuals with inconsistent results. Although sex differences in neural and behavioral features of nicotine dependence are reported, sex differences in regional GMV remain unknown. The current study examined sex differences in GMV in a large sample of 80 NDs (41 males) and 80 healthy controls (41 males) using voxel-based morphometry. Within NDs, we explored whether GMV was correlated with measures of cigarette use and nicotine dependence. High-resolution T1 structural scans were obtained from all participants. Segmentation and registration were performed in SPM8 using the optimized DARTEL approach. Covariates included age and an estimate of total global GMV. Differences were considered significant at p≤0.001, with a whole brain FWE-corrected cluster probability of p<0.025. Among NDs compared to Controls less GMV was observed in the thalamus and bilateral cerebellum and greater GMV was observed in the bilateral putamen and right parahippocampus. Lower thalamic GMV was observed in both female and male NDs compared to Controls. Female NDs also had lower GMV in the left cerebellum and in the ventral medial and orbitofrontal cortices with no areas of greater GMV. Male NDs had lower GMV in bilateral cerebellum and greater GMV in bilateral parahippocampus and left putamen. Within male NDs, GMV in the left putamen was correlated with number of pack years. This study, conducted in a large cohort, contributes to our knowledge of brain morphology in nicotine addiction and provides additional evidence of sex-specific effects on GMV in NDs. Identifying brain vulnerabilities with respect to sex provides a methodological framework for personalized therapies to improve relapse rates for both sexes.  相似文献   
110.
1. The pleopods of C. californiensis, a potential site for extrabranchial oxygen exchange, do not contribute significantly to oxygen consumption. 2. C. californiensis has a gill surface area of 4.13 +/- 0.72 cm2/g wet body weight, the lowest value yet reported for a totally aquatic crustacean. 3. C. californiensis, when placed in simulated burrow conditions, regulates the PO2 very loosely in its immediate microhabitat, using its pleopods. 4. Field studies of pH and PO2 values in burrows of C. californiensis indicate that animal movement may play a large part in water exchange between the surface and burrow. 5. Activity studies suggest that oxygen is not critical to C. californiensis on a short term basis. Perception of oxygen after long deprivation may signal the possibility of renewed feeding and activity at the surface of its burrow.  相似文献   
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