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141.
Harrison LM Morris JA Lauder RM Telford DR 《FEMS immunology and medical microbiology》2008,54(1):137-143
We investigated the effect of carriage of Staphylococcus aureus in the later stages of pregnancy on levels of antibody specific to the S. aureus toxins, staphylococcal enterotoxin B (SEB), staphylococcal enterotoxin C (SEC) and toxic shock syndrome toxin-1 (TSST-1), in cord blood and breast milk and also explored the relationship between levels of antibody in antenatal serum and cord blood. Nasopharyngeal swabs and stool samples were collected on two occasions, from 96 women, during the last 6 weeks of pregnancy. Samples were cultured and S. aureus isolates were identified. Antenatal and cord blood samples from the same women and their infants were analysed for IgG antibody to SEB, SEC and TSST-1 by enzyme-linked immunosorbent assay. Breast milk samples were analysed for IgA antibody to the same toxins. We found that S. aureus carriage in pregnancy is common and exposure to a toxin-producing isolate boosts immunity. Over 89% of women and infants have some protective antibody to the toxins, and antitoxin IgG levels are higher in cord blood samples compared with antenatal samples. Levels of cord blood IgG and breast milk IgA specific for the staphylococcal toxins vary. Some infants lack protection and could be at risk of toxin-induced disease. 相似文献
142.
In this article, we review the immunohistochemical evidence for the pathway-specific expression of co-existing neuropeptides in autonomic vasomotor neurons, and examine the functional significance of these expression patterns for the autonomic regulation of the vasculature. Most final motor neurons in autonomic vasomotor pathways contain neuropeptides in addition to non-peptide co-transmitters such as catecholamines, acetylcholine and nitric oxide. Neuropeptides also occur in preganglionic vasomotor neurons. The precise combinations of neuropeptides expressed by neurons in vasomotor pathways vary with species, vascular bed, and the level within the vascular bed. This applies to both vasoconstrictor and vasodilator pathways. There is a similar degree of variation in the expression of neuropeptide receptors in the vasculature. Consequently, the contributions of different peptides to autonomic vasomotor control are closely matched to the functional requirements of specific vascular beds. This arrangement allows for a high degree of precision in vascular control in normal conditions and has the potential for considerable plasticity under pathophysiological conditions. 相似文献
143.
Mohammed
H. Hassan Sawsan Abuhamdah Mohamed Abdel-Bary Mohammed Wahman Tarek
Hamdy Abd-Elhamid Morris Beshay Karam Mosallam Bakheet
E.M. Elsadek 《Bioscience reports》2021,41(1)
Survivin is an inhibitor of apoptosis as well as a promoter of cell proliferation. Fibulin-3 is a matrix glycoprotein that displays potential for tumor suppression or propagation. The present study aimed to validate the expression levels of survivin and fibulin-3 in benign and malignant respiratory diseases. This case–control study included 219 patients categorized into five groups. Group A included 63 patients with lung cancer, group B included 63 patients with various benign lung diseases, group D included 45 patients with malignant pleural mesothelioma (MPM), and group E included 48 patients with various benign pleural diseases. Group C included 60 healthy individuals (control group). Serum survivin and fibulin-3 levels were measured by ELISA, whereas their nuclear expressions in the lung and pleura were assessed via Western blot analysis. The results showed significantly higher survivin serum levels and significantly lower fibulin-3 levels in group A compared with in group B and controls (P<0.001). There were significantly higher serum levels of survivin and fibulin-3 in group D compared with in group E and controls (P<0.001), consistent with observed nuclear survivin and fibulin-3 expression levels. Fibulin-3 was determined to have higher value than survivin in discriminating lung cancer from MPM (P<0.05). Survivin and fibulin-3 could be useful diagnostic markers for lung and pleural cancers, and fibulin-3 expression was particularly useful in differentiating lung cancer from MPM. 相似文献
144.
A leucine to proline mutation in puroindoline b is frequently present in hard wheats from Northern Europe 总被引:14,自引:0,他引:14
M. Lillemo C. F. Morris 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(7):1100-1107
Endosperm hardness in wheat (Triticum aestivum L.) is determined by one major genetic factor, the Hardness (Ha) gene on the short arm of chromosome 5D. Grain hardness has previously been reported to result from either a failure to express
puroindoline a (Pina–D1b) or a glycine to serine mutation at position 46 in puroindoline b (Pinb–D1b). In this study, which involves a large survey of 343 wheat genotypes of mostly Northern European origin, we report two new
mutations in puroindoline b associated with hard endosperm. These were characterized as involving a leucine to proline change
at position 60 (Pinb–D1c), and a tryptophan to arginine change at position 44 (Pinb–D1d), respectively. While the former seems to be widely distributed in germplasm around the world, the latter was only found
in three winter wheats from Sweden and Netherlands. As discussed in the paper, the three known mutations in puroindoline b
can be considered ”loss-of-function” mutations (i.e. soft to hard), and structural analysis may serve to predict that their
dramatic effect on wheat grain texture is a result of reduced lipid–binding ability.
Received: 10 June 1999 / Accepted: 21 September 1999 相似文献
145.
Kelly A. Morris David B. Langston Donald W. Dickson Richard F. Davis Patricia Timper James P. Noe 《Journal of nematology》2015,47(4):310-315
Vegetable crops in the southeastern United States are commonly grown on plastic mulch with two crop cycles produced on a single mulch application. Field trials were conducted in 2013 and 2014 in two locations to evaluate the efficacy of fluensulfone for controlling Meloidogyne spp. when applied through drip irrigation to cucumber in a tomato–cucumber double-cropping system. In the spring tomato crop, 1,3-dichloropropene (1,3-D), fluensulfone, and a resistant cultivar significantly decreased root galling by 91%, 73%, and 97%, respectively, compared to the untreated control. Tomato plots from the spring were divided into split plots for the fall where the main plots were the spring treatment and the subplots were cucumber either treated with fluensulfone (3.0 kg a.i./ha. via drip irrigation) or left untreated. The fall application of fluensulfone improved cucumber vigor and reduced gall ratings compared to untreated subplots. Fluensulfone reduced damage from root-knot nematodes when applied to the first crop as well as provided additional protection to the second crop when it was applied through a drip system. 相似文献
146.
Molecular and Cellular Biochemistry - Ginseng is an ancient perennial herb belonging to the family Araliaceae and genus Panax which has been used for medical therapeutics for thousands of years,... 相似文献
147.
148.
Mark T. Gladwin Robyn J. Barst J. Simon R. Gibbs Mariana Hildesheim Vandana Sachdev Mehdi Nouraie Kathryn L. Hassell Jane A. Little Dean E. Schraufnagel Lakshmanan Krishnamurti Enrico Novelli Reda E. Girgis Claudia R. Morris Erika Berman Rosenzweig David B. Badesch Sophie Lanzkron Oswaldo L. Castro James G. Taylor VI Jonathan C. Goldsmith Gregory J. Kato Victor R. Gordeuk Roberto F. Machado 《PloS one》2014,9(7)
Background
The role of pulmonary hypertension as a cause of mortality in sickle cell disease (SCD) is controversial.Methods and Results
We evaluated the relationship between an elevated estimated pulmonary artery systolic pressure and mortality in patients with SCD. We followed patients from the walk-PHaSST screening cohort for a median of 29 months. A tricuspid regurgitation velocity (TRV)≥3.0 m/s cuttof, which has a 67–75% positive predictive value for mean pulmonary artery pressure ≥25 mm Hg was used. Among 572 subjects, 11.2% had TRV≥3.0 m/sec. Among 582 with a measured NT-proBNP, 24.1% had values ≥160 pg/mL. Of 22 deaths during follow-up, 50% had a TRV≥3.0 m/sec. At 24 months the cumulative survival was 83% with TRV≥3.0 m/sec and 98% with TRV<3.0 m/sec (p<0.0001). The hazard ratios for death were 11.1 (95% CI 4.1–30.1; p<0.0001) for TRV≥3.0 m/sec, 4.6 (1.8–11.3; p = 0.001) for NT-proBNP≥160 pg/mL, and 14.9 (5.5–39.9; p<0.0001) for both TRV≥3.0 m/sec and NT-proBNP≥160 pg/mL. Age >47 years, male gender, chronic transfusions, WHO class III–IV, increased hemolytic markers, ferritin and creatinine were also associated with increased risk of death.Conclusions
A TRV≥3.0 m/sec occurs in approximately 10% of individuals and has the highest risk for death of any measured variable.The study is registered in ClinicalTrials.gov with identifier
NCT00492531相似文献149.
Rajapurohitam V Kilic A Javadov S Karmazyn M 《Molecular and cellular biochemistry》2012,366(1-2):287-297
We recently identified leptin as a downstream factor mediating the hypertrophic effects of both angiotensin II and endothelin-1 in cardiomyocytes, an effect dependent on increased leptin biosynthesis, however, the mechanism for such increased leptin production is not known. This study was designed to elucidate the mechanisms underlying angiotensin II- and endothelin-1-stimulated synthesis in cultured ventricular myocytes. The hypertrophic effects of both angiotensin II (100 nM) and endothelin-1 (10 nM) were associated with increased leptin secretion and gene expression by 40 and 50 %, and 86 and 68 %, respectively. These effects were associated with significantly increased nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) phosphorylation by 34 and 52 %, as well as enhanced translocation of NF-κB into nuclei and also the NF-κB-DNA binding activity by 35 and 31 % induced by angiotensin II and endothelin-1, respectively. On their own, 24 h treatment with either angiotensin II or endothelin-1 increased cell surface area by 30 and 40 %, protein synthesis by 30 % and the α-skeletal actin gene by 53 and 68 %, respectively, indicating a robust hypertrophic effect whereas this was completely prevented by NF-κB inhibition. In addition, NF-κB inhibition significantly attenuated angiotensin II and endothelin-1-induced p38 MAPK activation whereas inhibition of p38 MAPK blocked both angiotensin II- and endothelin-1-induced increases in leptin secretion. The ability of both angiotensin II- and endothelin-1 to increase leptin production in cardiomyocytes and the resultant hypertrophic response are mediated by NF-κB and dependent on p38 MAPK activation. 相似文献
150.
L De Colibus AF Sonnen KJ Morris CA Siebert P Abrusci J Plitzko V Hodnik M Leippe E Volpi G Anderluh RJ Gilbert 《Structure (London, England : 1993)》2012,20(9):1498-1507
Pore-forming proteins insert from solution into membranes to create lesions, undergoing a structural rearrangement often accompanied by oligomerization. Lysenin, a pore-forming toxin from the earthworm Eisenia fetida, specifically interacts with sphingomyelin (SM) and may confer innate immunity against parasites by attacking their membranes to form pores. SM has important roles in cell membranes and lysenin is a popular SM-labeling reagent. The structure of lysenin suggests common ancestry with other pore-forming proteins from a diverse set of eukaryotes and prokaryotes. The complex with SM shows the mode of its recognition by a protein in which both the phosphocholine headgroup and one acyl tail are specifically bound. Lipid interaction studies and assays using viable target cells confirm the functional reliance of lysenin on this form of SM recognition. 相似文献