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Background

Frequent painful vaso-occlusive crises (VOCs) were associated with mortality in the Cooperative Study of Sickle Cell Disease (CSSCD) over twenty years ago. Modern therapies for sickle cell anemia (SCA) like hydroxyurea are believed to have improved overall patient survival. The current study sought to determine the relevance of the association between more frequent VOCs and death and its relative impact upon overall mortality compared to other known risk factors in a contemporary adult SCA cohort.

Methods

Two hundred sixty four SCA adults were assigned into two groups based on patient reported outcomes for emergency department (ED) visits or hospitalizations for painful VOC treatment during the 12 months prior to evaluation.

Results

Higher baseline hematocrit (p = 0.0008), ferritin (p = 0.005), and HDL cholesterol (p = 0.01) were independently associated with 1 or more painful VOCs requiring an ED visit or hospitalization for acute pain. During a median follow-up of 5 years, mortality was higher in the ED visit/hospitalization group (relative risk [RR] 2.68, 95% CI 1.1-6.5, p = 0.03). Higher tricuspid regurgitatant jet velocity (TRV) (RR 2.41, 95% CI 1.5-3.9, p < 0.0001), elevated ferritin (RR 4.00, 95% CI 1.8-9.0, p = 0.001) and lower glomerular filtration rate (RR=2.73, 95% CI 1.6-4.6, p < 0.0001) were also independent risk factors for mortality.

Conclusions

Severe painful VOCs remain a marker for SCA disease severity and premature mortality in a modern cohort along with other known risk factors for death including high TRV, high ferritin and lower renal function. The number of patient reported pain crises requiring healthcare utilization is an easily obtained outcome that could help to identify high risk patients for disease modifying therapies.

Trial Registration

ClinicalTrials.gov NCT00011648 http://clinicaltrials.gov/  相似文献   
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The most abundant marine fungi encountered in various regions of the Sea of Japan belong to the genera Penicillium, Aspergillus, Wardomyces, Trichoderma, Chrysosporium, and Chaetomium. Facultative marine fungi of the genera Scytalidium, Verticillium, and Oidiodendron and obligate marine fungi of the genus Dendryphiella are much less abundant. The composition of marine sediments and the anthropogenic load on them were found to influence the abundance and species diversity of fungi, as well as the occurrence of fungal strains producing hemolytically active substances. The biodiversity of mycobiota and the abundance of hemotoxin-producing fungi in marine sediments may be used to evaluate the anthropogenic load on marine biocenoses. Hemolytic compounds were produced by 57% of the fungi isolated from marine sediments. The hemolytic activity of Chaetomium spiculipilium was revealed in the fraction of the culture liquid containing extracellular fatty acids and pigments. The fatty acid composition of this marine fungus was determined.  相似文献   
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Effects of medium viscosity on kinetic parameters of poly(U) hydrolysis catalyzed by RNase from Bac. intermedius 7P (binase) were studied in solutions of sucrose (4-50 wt. %) and glycerol (35-62 wt. %) in Tris--sodium acetate buffer (pH 7.5) at 25 degreesC. The rate constant of reaction kcat was practically unchanged over a wide range of viscosities (1-15 cP for sucrose and 2.5-3 cP for glycerol). In glycerol solutions, kcat slightly increased with viscosity increase from 4 to 10 cP. Addition of NaCl to the buffer medium resulted in an inhibitory effect of Na+ on kcat, prevented by 50% sucrose or 60% glycerol. It is concluded that binase-catalyzed poly(U) cleavage occurs through a "tense"-substrate mechanism, similarly to reactions catalyzed by alpha-chymotrypsin, trypsin, and laccase.  相似文献   
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Summary : FT is a tool written in C++, which implements the Fourier analysis method to locate periodicities in aminoacid or DNA sequences. It is provided for free public use on a WWW server with a Java interface. Availability : The server address is http://o2.db. uoa.gr/FT Contact : shamodr@atlas.uoa.gr   相似文献   
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The taxonomic study of two Gram-negative, aerobic, non-pigmented bacteria KMM 9010T and KMM 9023T isolated from a sandy sediment sample collected from the Sea of Japan seashore was performed. On the basis of the nearly complete 16S rRNA gene sequences, strains KMM 9010T and KMM 9023T clustered with the Roseobacter lineage (class Alphaproteobacteria) forming a distinct phylogenetic line adjacent to the genus Donghicola. Novel strains shared the highest sequence similarity of 96.4% to each other and lower than 96.1% similarities to other validly named genera of the class Alphaproteobacteria. In both strains, ubiquinone Q-10 was found to be the major respiratory quinone; phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidic acid, and an unknown aminolipid were the major polar lipids and C18:1ω7c and 11-methyl C18:1ω7c were predominant fatty acids. The DNA G+C content was 60.5 mol% (KMM 9010T) and 65.4 mol% (KMM 9023T). Based on phenotypic properties and phylogenetic evidence, strains KMM 9010T and KMM 9023T should be classified as two novel species in a new genus, Poseidonocella gen. nov., with Poseidonocella pacifica sp. nov., the type species with the type strain KMM 9010T (= NRIC 0794T = JCM 17310T), and Poseidonocella sedimentorum sp. nov. as the second species with the type strain KMM 9023T (= NRIC 0796T = JCM 17311T).  相似文献   
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The fatty acid (FA) composition and the content of the prostaglandin PGE2 were determined in the red algae Gracilaria vermiculophylla and G. austramaritima from Peter the Great Bay (Sea of Japan), as well as in G. tenuistupitata, G. ?hangii, and G. bailiniae from lagoons in southern Vietnam (in the South China Sea). Polyunsaturated FA (PUFA) comprised 49?C56% of the total FAs in algae from the Sea of Japan, while in algae from the South China Sea their share was 20% at most. The content of arachidonic acid (20:4n-6) in the total FAs of G. vermiculophylla was as high as 45.4%, while the level of 20:4n-6 in Gracilaria from coastal waters of Vietnam did not exceed 12.5%. G. austramaritima stood out for its high content of eicosapentaenoic acid 20:5n-3 (33.5%). The ratios of 20:4n-6/20:5n-3 in G. vermiculophylla, G. austramaritima, G. tenuistupitata, G. changii, and G. bailiniae were 10.6, 0.3, 3.9, 4.0, and 1.5, respectively. The content of PGE2 was the highest (286 ??g/g dry weight) in G. vermiculophylla from the Sea of Japan and did not exceed 20 ??g/g dry weights in other Gracilaria species. This study showed that it is possible to introduce G. vermiculophylla from the Sea of Japan into the mariculture of northern Vietnam. In the experiment, during 3 weeks of cultivation, the biomass of introduced Gracilaria increased 1.2?C1.3 times in a sea lagoon in Vietnam and 1.5?C2 times in an aquarium; the algal growth rates were 1.57 ± 0.21% per day. In cultivated Gracilaria, the level of 20:4n-6 decreased to 5.9% (20:4n-6/20:5n-3 = 2.3) and the level of PGE2 decreased to 12 ??g/g in dry weight. The PUFA compositions of G. vermiculophylla from various natural populations differed insignificantly; however, the stress caused by introduction led to a sharp reduction in the content of 20:4n-6, which was probably connected with a decreased biosynthesis rate of PUFAs of the n-6 series. At the same time, approximately equal amounts of PGE2 methyl ester were extracted from natural and cultivated G. vermiculophylla after treatment by a method proposed for obtaining prostaglandins. Thus, the cultivation conditions evidently did not influence the prostaglandin biosynthesis enzyme complex in G. vermiculophylla; this species, when grown in mariculture, can be used as a source of prostaglandins.  相似文献   
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The onset of incubation before the end of laying imposes asynchrony at hatching and, therefore, a size hierarchy in the brood. It has been argued that hatching asynchrony might be a strategy to improve reproductive output in terms of quality or quantity of offspring. However, little is known about the mediating effect of hatching asynchrony on offspring quality when brood reduction occurs. Here, we investigate the relationship between phenotypic quality and hatching asynchrony in Common Kestrel Falco tinnunculus nestlings in Spain. Hatching asynchrony did not increase breeding success or nestling quality. Furthermore, hatching asynchrony and brood reduction had different effects on nestlings’ phytohaematogglutinin (PHA)‐mediated immune response and nestling growth. In asynchronous and reduced broods (in which at least one nestling died), nestlings showed a stronger PHA‐mediated immune response and tended to have a smaller body size compared with nestlings raised in synchronous and reduced broods. When brood reduction occurred in broods hatched synchronously, there was no effect on nestling size, but nestlings had a relatively poor PHA‐mediated immune response compared with nestlings raised in asynchronous and reduced broods. We suggest that resources for growth can be directed to immune function only in asynchronously hatched broods, resulting in improved nestling quality, as suggested by their immune response. We also found that males produced a greater PHA‐mediated immune response than females only in brood‐reduced nests without any effect on nestling size or condition, suggesting that females may trade off immune activities and body condition, size or weight. Overall, our results suggest that hatching pattern and brood reduction may mediate resource allocation to different fitness traits. They also highlight that the resolution of immune‐related trade‐offs when brood reduction occurs may differ between male and female nestlings.  相似文献   
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