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41.
A high-performance liquid chromatography method has been developed for fractionating the protein components of the lung's extracellular lining fluid, as sampled by bronchoalveolar lavage. With this method, 10 ml (or less) of rat bronchoalveolar lavage fluid (BALF) in phosphate-buffered saline can be quantitatively analyzed rapidly and reproducibly. This volume (25% of the lavage fluid volume from one rat using a standardized lavage technique) is made 0.2% with respect to trifluoroacetic acid (TFA) and pumped through a microBondapak C18 Radial-PAK HPLC column equilibrated with H2O/0.2% TFA. Six fractions are then eluted with a series of acetonitrile gradients and isocratic steps that progress from H2O/0.2% TFA to 65% CH3 CN/0.2% TFA. Following this, 5 additional fractions are eluted with methanol. All 11 fractions are detected by monitoring the column effluents at 206 nm and can be recovered by lyophilization since all the components of the HPLC solvent system are volatile. Nine of the 11 fractions were found to contain protein. Three of the fractions contained proteins common to the blood compartment. The largest fraction of these was albumin, followed by a fraction containing immunoglobulins. Six other protein fractions appeared to be derived from the cells of the lung inasmuch as they were not detected in plasma. Two fractions contained no protein or phospholipids, whereas the most hydrophobic protein fraction did contain phospholipids. A major phospholipid fraction containing no protein eluted early in the chromatogram and was not detectable at 206 nm. This HPLC procedure offers significant utility for identifying and quantifying alterations in several BALF constituents during the development and progression of environmentally induced lung diseases as well as other pulmonary disorders.  相似文献   
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43.

The tomato–potato psyllid (TPP) Bactericera cockerelli, is a serious pest of solanaceous crops. Some populations are becoming pesticide-resistant, increasing the need for alternatives such as biological control (BC). This approach may be improved by combining different species of BC agents. We conducted three separate experiments to test four BC agents, either alone or combined with others: (1) A laboratory assay to test the effect of buckwheat (Fagopyrum esculentum) and alyssum (Lobularia maritima) flowers on the longevity of females of the parasitic wasp Tamarixia triozae; (2) A no-choice laboratory assay to investigate the consumption of B. cockerelli life stages by the predatory bug Engytatus nicotianae; (3) A cage experiment in a greenhouse to assess four natural enemy species against B. cockerelli on tomatoes: these were the predators Cleobora mellyi, Amblydromalus limonicus, E. nicotianae, and T. triozae. Access to buckwheat flowers allowed female T. triozae to live for an average of 10.9 days compared to 2.1 days with alyssum and 1.4 day with water but did not improve the BC of B. cockerelli. Adult E. nicotianae preyed on all offered B. cockerelli stages. In experiment 3, combinations of T. triozae with A. limonicus or E. nicotianae were not significantly better than single natural enemy species, except for the reduction of nymphal populations when A. limonicus and T. triozae were combined. Although there were few significant reductions in numbers of TPP when using natural enemy species combinations, some species showed good potential when used alone. We suggest testing earlier release of combinations of natural enemy for evaluate its impact on TPP.

  相似文献   
44.
Asthma originates from genetic and environmental factors with about half the risk of disease attributable to heritable causes. Genome-wide association studies, mostly in populations of European ancestry, have identified numerous asthma-associated single nucleotide polymorphisms (SNPs). Studies in populations with diverse ancestries allow both for identification of robust associations that replicate across ethnic groups and for improved resolution of associated loci due to different patterns of linkage disequilibrium between ethnic groups. Here we report on an analysis of 745 African-American subjects with asthma and 3,238 African-American control subjects from the Candidate Gene Association Resource (CARe) Consortium, including analysis of SNPs imputed using 1,000 Genomes reference panels and adjustment for local ancestry. We show strong evidence that variation near RAD50/IL13, implicated in studies of European ancestry individuals, replicates in individuals largely of African ancestry. Fine mapping in African ancestry populations also refined the variants of interest for this association. We also provide strong or nominal evidence of replication at loci near ORMDL3/GSDMB, IL1RL1/IL18R1, and 10p14, all previously associated with asthma in European or Japanese populations, but not at the PYHIN1 locus previously reported in studies of African-American samples. These results improve the understanding of asthma genetics and further demonstrate the utility of genetic studies in populations other than those of largely European ancestry.  相似文献   
45.
TTLL5/STAMP (tubulin tyrosine ligase-like family member 5) has multiple activities in cells. TTLL5 is one of 13 TTLLs, has polyglutamylation activity, augments the activity of p160 coactivators (SRC-1 and TIF2) in glucocorticoid receptor-regulated gene induction and repression, and displays steroid-independent growth activity with several cell types. To examine TTLL5/STAMP functions in whole animals, mice were prepared with an internal deletion that eliminated several activities of the Stamp gene. This mutation causes both reduced levels of STAMP mRNA and C-terminal truncation of STAMP protein. Homozygous targeted mutant (Stamptm/tm) mice appear normal except for marked decreases in male fertility associated with defects in progressive sperm motility. Abnormal axonemal structures with loss of tubulin doublets occur in most Stamptm/tm sperm tails in conjunction with substantial reduction in α-tubulin polyglutamylation, which closely correlates with the reduction in mutant STAMP mRNA. The axonemes in other structures appear unaffected. There is no obvious change in the organs for sperm development of WT versus Stamptm/tm males despite the levels of WT STAMP mRNA in testes being 20-fold higher than in any other organ examined. This defect in male fertility is unrelated to other Ttll genes or 24 genes previously identified as important for sperm function. Thus, STAMP appears to participate in a unique, tissue-selective TTLL-mediated pathway for α-tubulin polyglutamylation that is required for sperm maturation and motility and may be relevant for male fertility.  相似文献   
46.

Background

Swine influenza is an infectious acute respiratory disease of pigs caused by influenza A virus. We investigated the time of entry of swine influenza into the Finnish pig population. We also describe the molecular detection of two types of influenza A (H1N1) viruses in porcine samples submitted in 2009 and 2010.This retrospective study was based on three categories of samples: blood samples collected for disease monitoring from pigs at major slaughterhouses from 2007 to 2009; blood samples from pigs in farms with a special health status taken in 2008 and 2009; and diagnostic blood samples from pigs in farms with clinical signs of respiratory disease in 2008 and 2009.The blood samples were tested for influenza A antibodies with an antibody ELISA. Positive samples were further analyzed for H1N1, H3N2, and H1N2 antibodies with a hemagglutination inhibition test.Diagnostic samples for virus detection were subjected to influenza A M-gene-specific real-time RT-PCR and to pandemic influenza A H1N1-specific real-time RT-PCR. Positive samples were further analyzed with RT-PCRs designed for this purpose, and the PCR products were sequenced and sequences analyzed phylogenetically.

Results

In the blood samples from pigs in special health class farms producing replacement animals and in diagnostic blood samples, the first serologically positive samples originated from the period July–August 2008. In samples collected for disease monitoring, < 0.1%, 0% and 16% were positive for antibodies against influenza A H1N1 in the HI test in 2007, 2008, and 2009, respectively.Swine influenza A virus of avian-like H1N1 was first detected in diagnostic samples in February 2009. In 2009 and 2010, the avian-like H1N1 virus was detected on 12 and two farms, respectively. The pandemic H1N1 virus (A(H1N1)pdm09) was detected on one pig farm in 2009 and on two farms in 2010.

Conclusions

Based on our study, swine influenza of avian-like H1N1 virus was introduced into the Finnish pig population in 2008 and A(H1N1)pdm09 virus in 2009. The source of avian-like H1N1 infection could not be determined. Cases of pandemic H1N1 in pigs coincided with the period when the A(H1N1)pdm09 virus was spread in humans in Finland.
  相似文献   
47.
48.

Background

Studies on ragweed and birch pollen extracts suggested that the adenosine content is an important factor in allergic sensitization. However, exposure levels from other pollens and considerations of geographic and seasonal factors have not been evaluated.

Objective

This study compared the metabolite profile of pollen species important for allergic disease, specifically measured the adenosine content, and evaluated exposure to pollen-derived adenosine.

Methods

An NMR metabolomics approach was used to measure metabolite concentrations in 26 pollen extracts. Pollen count data was analyzed from five cities to model exposure.

Results

A principal component analysis of the various metabolites identified by NMR showed that pollen extracts could be differentiated primarily by sugar content: glucose, fructose, sucrose, and myo-inositol. In extracts of 10 mg of pollen/ml, the adenosine was highest for grasses (45 µM) followed by trees (23 µM) and weeds (19 µM). Pollen count data showed that tree pollen was typically 5–10 times the amount of other pollens. At the daily peaks of tree, grass, and weed season the pollen-derived adenosine exposure per day is likely to be only 1.1, 0.11, and 0.12 µg, respectively. Seasonal models of pollen exposure and respiration suggest that it would be a rare event limited to tree pollen season for concentrations of pollen-derived adenosine to approach physiological levels.

Conclusion

Sugar content and other metabolites may be useful in classifying pollens. Unless other factors create localized exposures that are very different from these models, pollen-derived adenosine is unlikely to be a major factor in allergic sensitization.
  相似文献   
49.
DNA Polymerase β is a multifunctional enzyme involved in base excision repair of nuclear DNA in vertebrate cells. We present here the first assignments of the full-length protein (335 residues, 39 kDa) in the presence of a double gap—double hairpin DNA (22 nucleotides, 7 kDa).  相似文献   
50.
Sterol structure influences liquid ordered domains in membranes, and the dependence of biological functions on sterol structure can help identify processes dependent on ordered domains. In this study we compared the effect of sterol structure on ordered domain formation in symmetric vesicles composed of mixtures of sphingomyelin, 1, 2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and cholesterol, and in asymmetric vesicles in which sphingomyelin was introduced into the outer leaflet of vesicles composed of DOPC and cholesterol. In most cases, sterol behavior was similar in symmetric and asymmetric vesicles, with ordered domains most strongly stabilized by 7-dehydrocholesterol (7DHC) and cholesterol, stabilized to a moderate degree by lanosterol, epicholesterol and desmosterol, and very little if at all by 4-cholesten-3-one. However, in asymmetric vesicles desmosterol stabilized ordered domain almost as well as cholesterol, and to a much greater degree than epicholesterol, so that the ability to support ordered domains decreased in the order 7-DHC > cholesterol > desmosterol > lanosterol > epicholesterol > 4-cholesten-3-one. This contrasts with values for intermediate stabilizing sterols in symmetric vesicles in which the ranking was cholesterol > lanosterol ~ desmosterol ~ epicholesterol or prior studies in which the ranking was cholesterol ~ epicholesterol > lanosterol ~ desmosterol. The reasons for these differences are discussed. Based on these results, we re-evaluated our prior studies in cells and conclude that endocytosis levels and bacterial uptake are even more closely correlated with the ability of sterols to form ordered domains than previously thought, and do not necessarily require that a sterol have a 3β-OH group.  相似文献   
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