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891.
Abstract— Glial cells were isolated from bovine white matter by differential centrifugation. The fatty aldehyde and fatty acid compositions of ethanolamine glycerophosphatides (EGP), serine glycerophosphatides (SGP) and choline glycerophosphatides (CGP) were determined by gas-liquid chromatography. The fatty acid compositions of the sphingo-lipids including sphingomyelin, cerebroside and cerebroside sulphate, and of minor lipid components including cholesterol esters and triglycerides, were also determined by gas-liquid chromatography. The relative proportions correlated closely with the results obtained by O'B rien and S ampson (1965 b ) for adult human brain. The fatty aldehyde compositions of the glycerophosphatides were more closely related to the corresponding fatty acid compositions of the plasma membrane than of the mitochondria. Long-chain fatty acids (19–26 carbon atoms) were detected in sphingomyelin, cerebroside and cerebroside sulphate; this indicates that chain-elongation beyond C18 occurs in the glial cells.  相似文献   
892.

Background

Classification of acute decompensated heart failure (ADHF) is based on subjective criteria that crudely capture disease heterogeneity. Improved phenotyping of the syndrome may help improve therapeutic strategies.

Objective

To derive cluster analysis-based groupings for patients hospitalized with ADHF, and compare their prognostic performance to hemodynamic classifications derived at the bedside.

Methods

We performed a cluster analysis on baseline clinical variables and PAC measurements of 172 ADHF patients from the ESCAPE trial. Employing regression techniques, we examined associations between clusters and clinically determined hemodynamic profiles (warm/cold/wet/dry). We assessed association with clinical outcomes using Cox proportional hazards models. Likelihood ratio tests were used to compare the prognostic value of cluster data to that of hemodynamic data.

Results

We identified four advanced HF clusters: 1) male Caucasians with ischemic cardiomyopathy, multiple comorbidities, lowest B-type natriuretic peptide (BNP) levels; 2) females with non-ischemic cardiomyopathy, few comorbidities, most favorable hemodynamics; 3) young African American males with non-ischemic cardiomyopathy, most adverse hemodynamics, advanced disease; and 4) older Caucasians with ischemic cardiomyopathy, concomitant renal insufficiency, highest BNP levels. There was no association between clusters and bedside-derived hemodynamic profiles (p = 0.70). For all adverse clinical outcomes, Cluster 4 had the highest risk, and Cluster 2, the lowest. Compared to Cluster 4, Clusters 1–3 had 45–70% lower risk of all-cause mortality. Clusters were significantly associated with clinical outcomes, whereas hemodynamic profiles were not.

Conclusions

By clustering patients with similar objective variables, we identified four clinically relevant phenotypes of ADHF patients, with no discernable relationship to hemodynamic profiles, but distinct associations with adverse outcomes. Our analysis suggests that ADHF classification using simultaneous considerations of etiology, comorbid conditions, and biomarker levels, may be superior to bedside classifications.  相似文献   
893.
Interspecific hybridization can be considered an accelerator of evolution, otherwise a slow process, solely dependent on mutation and recombination. Upon interspecific hybridization, several novel interactions between nuclear and cytoplasmic genomes emerge which provide additional sources of diversity. The magnitude and essence of intergenomic interactions between nuclear and cytoplasmic genomes remain unknown due to the direction of many crosses. This study was conducted to address the role of nuclear-cytoplasmic interactions as a source of variation upon hybridization. Wheat (Triticum aestivum) alloplasmic lines carrying the cytoplasm of Aegilops mutica along with an integrated approach utilizing comparative quantitative trait locus (QTL) and epigenome analysis were used to dissect this interaction. The results indicate that cytoplasmic genomes can modify the magnitude of QTL controlling certain physiological traits such as dry matter weight. Furthermore, methylation profiling analysis detected eight polymorphic regions affected by the cytoplasm type. In general, these results indicate that novel nuclear-cytoplasmic interactions can potentially trigger an epigenetic modification cascade in nuclear genes which eventually change the genetic network controlling physiological traits. These modified genetic networks can serve as new sources of variation to accelerate the evolutionary process. Furthermore, this variation can synthetically be produced by breeders in their programs to develop epigenomic-segregating lines.  相似文献   
894.
Within Fabaceae, legume species have a variable genome size, chromosome number, and ploidy level. The genome distribution of ribosomal genes, easily detectable by fluorescent in situ hybridization (FISH), is a good tool for anchoring physical and genetic comparative maps. The organisation of 45S rDNA and 5S loci was analysed by FISH in the 4 closely related species: Pisum sativum, Medicago truncatula, Medicago sativa (2 diploid taxa), and Lathyrus sativus. The 2 types of rDNA arrays displayed interspecific variation in locus number and location, but little intraspecific variation was detected. In the model legume, M. truncatula, the presence of 2 adjacent 45S rDNA loci was demonstrated, and the location of the rDNA loci was independent of the general evolution of the genome DNA. The different parameters relative to clustering of the rDNA loci in specific chromosome regions and the possible basis of rDNA instability are discussed.  相似文献   
895.
Cyclical parthenogenesis allows study of the genetic and evolutionary characteristics of groups exhibiting both asexual and sexual reproduction. The cladoceran genus Daphnia contains species which vary with respect to the relative incidence of sexual reproduction; pond species tend to undergo sexual reproduction more regularly than species found in large lakes. Previous genetic studies have focused on pond populations, generating expectations about large-lake populations that have not been fully met by recent studies. The present study of the Palearctic species Daphnia galeata further examines the genetic structure of large-lake populations. Nine local populations, from lakes in northern Germany, are examined for genetic variation at seven enzyme loci. Populations exhibit similar allelic arrays and often similar allele frequencies at the five polymorphic loci; values of Nei's genetic distance (D) ranged from 0.002 to 0.239, with a mean of 0.084. FST values range from 0.012 to 0.257, and spatial autocorrelation coefficients range from -0.533 to 0.551, for the eight alleles analyzed. With few exceptions, within-population genotypic frequencies were in Hardy-Weinberg equilibrium. There was, however, significant heterogeneity in genotypic frequencies among populations. The number of coexisting clonal groups, as determined by three locus genotypes, is high within populations. Clonal groups are widely distributed among localities. The amount of genetic divergence observed among these large-lake populations is smaller than that previously observed among pond populations and suggests that different processes may be important in determining the genetic structure and subsequent phenotypic divergence of lake versus pond populations.  相似文献   
896.
Cardiovascular diseases (CVD) constitute a significant risk and may, in part, explain the high morbidity and mortality rates among haemodialysis (HD) patients. Several studies have implicated reduced insulin like growth factor (IGF-1) levels in the development of CVD. However, it is not clear whether IGF-1, and its relationship with other hormones such as leptin, insulin, and growth hormone (GH), as well as anthropometric variables may explain the high incidence of vascular complications in chronic kidney disease (CKD) patients. This study was designed to measure total serum IGF-1, leptin, insulin and GH levels in CKD patients and in age-matched control subjects and to elucidate the relationship between IGF-1 and GH, leptin, and insulin as well as other known aetiological risk factors for CVD including blood pressure, body mass index (BMI), and age. The study consisted of 50 CKD patients [36 M and 14 F; mean age; 41.8 ± 10.3 years) on maintenance haemodialysis and 50 healthy control subjects (36 M and 14 F; mean age 41.6 ± 10.2 years) matched for age and sex. None of the subject among patients and controls reported either smoking or history of diabetes mellitus. The circulating levels of IGF-1 were significantly lower (P < 0.001) in both male and female patients compared to the control subjects. Moreover, IGF-1 was strongly and inversely correlated with both systolic blood pressure (SBP) (r = −0.360; P < 0.01) and diastolic blood pressure (DBP) (r = −0.512; P < 0.001) in the CKD group, and when the two groups were combined SBP (r = −0.396; P < 0.001) and DBP (r = −0.296; P < 0.01). When adjusted for age, the correlation was more significant, however, when adjusted for BMI no significant correlation was observed between IGF-1 and blood pressure. IGF-1 was inversely correlated with age (r = −0.367; P < 0.01) and BMI (r = −0.310; P < 0.05) in the control group, but not the patient group. In controls and patients, respectively, a positive correlation between leptin and BMI (r = 0.358; P < 0.01; r = 0.640, P < 0.001) was observed. The results show that circulating levels of IGF-1 were significantly lower in CKD patients as compared to healthy normal subjects and were inversely correlated with SBP and DBP independent of age, but not BMI indicative of a strong relationship between cardiovascular risk factors and low IGF-1 levels. Although, the data do not clearly indicate low IGF-1 levels as a cause or an effect of these cardiovascular risk factors, they do point to an interesting relationship between low IGF-1 levels and increased cardiovascular risk factors among CKD patients as compared to age-matched healthy control subjects.  相似文献   
897.
Measurement and monitoring of magnesium (Mg) are important to prevent the development of serious and potentially fatal complications in critically ill patients. Although ion-selective electrodes are available and earlier reports suggest that free ionized magnesium (iMg2+) is the most useful test to estimate Mg status, most clinical laboratories still only measure total Mg. To compare the relationship among iMg2+, total Mg, and albumin in serum, samples were collected from 48 consecutive patients admitted to an intensive care unit or a primary health center. The mean serum level of iMg2+ in 44 patients was 0.53 mmol/L, the total Mg was 0.06 mmol/L, and the albumin was 34.93 g/L. The correlation between iMg2+ and total Mg in serum was r=0.585; the correlation between iMg2+ and albumin in serum was r=378; and the correlation between total Mg and albumin in serum was r=0.340. The mean percent iMg2+ in relation to total Mg in serum was calculated to be 55% in the patient samples. The important level of biologically active iMg2+ was not reflected upon analysis of total Mg in 25% of consecutive patients. This report shows that the correlation of iMg2+ and total Mg is weak, not only in critically ill patients but also in patients in whom Mg status is inquired as a whole.  相似文献   
898.
Worldwide, vitamin D status is suboptimal relative to circulating levels of 25-hydroxyvitamin D (25OHD) needed to prevent a variety of chronic conditions, however, it has long been assumed that dietary intake is sufficient to meet needs when sun exposure is limited. In the USA, mean vitamin D intake from foods is close to 5 μg, the Dietary Reference Intake (DRI) recommendation for persons up to 50 years; however, the amount of vitamin D needed to maintain a sufficient 25OHD level during winter is >12.5 μg, and that needed for darkly pigmented, veiled, or sun protected persons is >50 μg. In the USA, most vitamin D intake from foods is provided by fortification. Canada and New Zealand have fewer fortified choices, and intakes are correspondingly lower. Supplement use can increase mean intake to >12.5 μg but does not always reach those who need it most. Serum 25OHD levels in New Zealand reveal much more insufficiency than expected, especially for Pacific people and Mäori; low serum 25OHD concentrations are seen throughout the Asia-Pacific region. Fortification and supplementation may be effective to achieve intakes of 12.5 μg vitamin D in some of the population, but for many achieving the amount needed in the absence of skin synthesis requires intakes above the current upper level for vitamin D of 50 μg.  相似文献   
899.
Two galloylglucosides, 6-hydroxy-eugenol 4-O-(6'-O-galloyl)-beta-D-4C1-glucopyranoside (4) and 3-(4-hydroxy-3-methoxyphenyl)-propane-1,2-diol-2-O-(2',6'-di-O-galloyl)-beta-D -4C1-glucopyranoside (7), and two C-glycosidic tannins, vascalaginone (10) and grandininol (14), together with fourteen known metabolites, gallic acid (1), methyl gallate (2), nilocitin (3), 1-O-galloyl-4,6-(S)-hexahydroxydiphenoyl-(alpha/beta)-D-glucopyranose (5), 4,6-(S)-hexahydroxydiphenoyl-(alpha/beta)-D-glucopyranose (6), 3,4,6-valoneoyl-(alpha/beta)-D-glucopyranose (8), pedunculagin (9), casuariin (11), castalagin (12), vascalagin (13), casuarinin (15), grandinin (16), methyl-flavogallonate (17) and ellagic acid (18), were identified from the leaves of Pimenta dioica (Merr.) L. (Myrtaceae) on the basis of their chemical and physicochemical analysis (UV, HRESI-MS, 1D and 2D NMR). It was found that 9 is the most cytotoxic compound against solid tumour cancer cells, the most potent scavenger against the artificial radical DPPH and physiological radicals including ROO*, OH*, and O2-*, and strongly inhibited the NO generation and induced the proliferation of T-lymphocytes and macrophages. On the other hand, 3 was the strongest NO inhibitor and 16 the highest stimulator for the proliferation of T-lymphocytes, while 10 was the most active inducer of macrophage proliferation.  相似文献   
900.
Geminal bisphosphonates can be used for a variety of purposes in human disease including reduction of bone resorption in osteoporosis, treatment of fractures associated with malignancies of the prostate, breast, and lung, and direct anticancer activity against bone marrow derived malignancies. Previous research led to identification of some novel isoprenoid bisphosphonates that inhibit geranylgeranyl pyrophosphate (GGPP) synthesis and diminish protein geranylgeranylation. Described here is the synthesis of fluorescent anthranilate analogues of the most active isoprenoid bisphosphonates and examine their ability to impact post-translational processing of the small GTPases Ras, Rap1a, and Rab6. Similar to their non-fluorescent counterparts, some of these fluorescent isoprenoid bisphosphonates diminish protein geranylgeranylation. Their biological activity and fluorescent character suggest that they may be useful in studies of bisphosphonate localization both in cultured cells and in whole organisms.  相似文献   
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