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61.
Helicobacter pylori is a cause of chronic gastritis and leads to development of atrophy in some cases. There is evidence that the heat shock protein 60 (HSP60) of H. pylori is involved in induction of chronic inflammation. Seroprevalence of IgG antibodies to H. pylori HSP60 in an adult cohort from Saaremaa, Estonia (68 persons, median age 57 years), with a high prevalence of antibodies to cell surface proteins of H. pylori (92%) and a well characterized dynamics of chronic gastritis in an 18-year follow-up study, was tested using purified H. pylori HSP60 at a concentration of 1 microg ml(-1) with ELISA. The state of the gastric mucosa and the presence of H. pylori in histological sections in the samples of 1979 and 1997 were assessed in accordance with the Sydney system. Seropositivity for H. pylori HSP60 was 65%. Immunological response to H. pylori HSP60 is associated with the morphological presence of H. pylori in the antrum and corpus (P=0.01) and is strongly correlated with the grade of chronic inflammation, particularly in the antrum mucosa (r=0.34; P=0.003; OR=5.97 (95% CI 1.21-29.3)), but is not associated with development of atrophy during 18 years of follow-up, or with the activity of gastritis. This finding supports the evidence that immunological response to H. pylori HSP60 may play a role in triggering of the inflammatory process in the gastric mucosa.  相似文献   
62.
Eucalyptus trees are among the most important species for industrial forestry worldwide. However, as with most forest trees, flowering does not begin for one to several years after planting which can limit the rate of conventional and molecular breeding. To speed flowering, we transformed a Eucalyptus grandis × urophylla hybrid (SP7) with a variety of constructs that enable overexpression of FLOWERING LOCUS T (FT). We found that FT expression led to very early flowering, with events showing floral buds within 1–5 months of transplanting to the glasshouse. The most rapid flowering was observed when the cauliflower mosaic virus 35S promoter was used to drive the Arabidopsis thaliana FT gene (AtFT). Early flowering was also observed with AtFT overexpression from a 409S ubiquitin promoter and under heat induction conditions with Populus trichocarpa FT1 (PtFT1) under control of a heat‐shock promoter. Early flowering trees grew robustly, but exhibited a highly branched phenotype compared to the strong apical dominance of nonflowering transgenic and control trees. AtFT‐induced flowers were morphologically normal and produced viable pollen grains and viable self‐ and cross‐pollinated seeds. Many self‐seedlings inherited AtFT and flowered early. FT overexpression‐induced flowering in Eucalyptus may be a valuable means for accelerating breeding and genetic studies as the transgene can be easily segregated away in progeny, restoring normal growth and form.  相似文献   
63.
To address the question whether the abundance of an invasive species can be explained by physical and chemical properties of the invaded ecosystems, we gathered density data of invasive zebra mussels and the physical and chemical data of ecosystems they invaded. We assembled published data from 55 European and 13 North American lakes and developed a model for zebra mussel density using a generalized additive model (GAM) approach. Our model revealed that the joint effect of surface area, total phosphorus and calcium concentrations explained 62% of the variation in Dreissena density. Our study indicates that large and less productive North American lakes can support larger local populations of zebra mussels. Our results suggest that the proliferation of an exotic species in an area can partially be explained by physical and chemical properties of the recipient environment.  相似文献   
64.
The chemoattractant receptor-homologous molecule expressed on T(H)2 cells (CRTH-2), also found on eosinophils and basophils, is a prostaglandin D2 receptor involved in the recruitment of these cell types during an inflammatory response. In this report, we describe the synthesis and optimization of a ramatroban isostere that is a selective and potent antagonist of CRTH-2 which may be useful in the treatment of certain diseases.  相似文献   
65.
The recommendations presented here are designed to support easier communication of NMR data and NMR structures of proteins and nucleic acids through unified nomenclature and reporting standards. Much of this document pertains to the reporting of data in journal articles; however, in the interest of the future development of structural biology, it is desirable that the bulk of the reported information be stored in computer-accessible form and be freely accessible to the scientific community in standardized formats for data exchange. These recommendations stem from an IUPAC-IUBMB-IUPAB inter-union venture with the direct involvement of ICSU and CODATA. The Task Group has reviewed previous formal recommendations and has extended them in the light of more recent developments in the field of biomolecular NMR spectroscopy. Drafts of the recommendations presented here have been examined critically by more than 50 specialists in the field and have gone through two rounds of extensive modification to incorporate suggestions and criticisms.  相似文献   
66.
67.
The acoustic startle response is an evolutionarily conserved avoidance behavior. Disruptions in startle behavior, particularly startle magnitude, are a hallmark of several human neurological disorders. While the neural circuitry underlying startle behavior has been studied extensively, the repertoire of genes and genetic pathways that regulate this locomotor behavior has not been explored using an unbiased genetic approach. To identify such genes, we took advantage of the stereotypic startle behavior in zebrafish larvae and performed a forward genetic screen coupled with whole genome analysis. We uncovered mutations in eight genes critical for startle behavior, including two genes encoding proteins associated with human neurological disorders, Dolichol kinase (Dolk), a broadly expressed regulator of the glycoprotein biosynthesis pathway, and the potassium Shaker-like channel subunit Kv1.1. We demonstrate that Kv1.1 and Dolk play critical roles in the spinal cord to regulate movement magnitude during the startle response and spontaneous swim movements. Moreover, we show that Kv1.1 protein is mislocalized in dolk mutants, suggesting they act in a common genetic pathway. Combined, our results identify a diverse set of eight genes, all associated with human disorders, that regulate zebrafish startle behavior and reveal a previously unappreciated role for Dolk and Kv1.1 in regulating movement magnitude via a common genetic pathway.  相似文献   
68.
A series of E,E,E-3,5-bis(arylidene)-1-(4-arylamino-4-oxo-2-butenoyl)-4-piperidones 4 (phenylidene) and 5 (4-nitrophenylidene) were prepared in order to explore the structural features of the N-acyl group which affects the cytotoxic potency. Evaluation toward human Molt 4/C8 and CEM T-lymphocytes revealed that many of the IC(50) figures were submicromolar and lower than melphalan. Marked inhibitory potencies toward murine leukemia L1210 cells were also noted. When evaluated against a panel of human tumor cell lines, three representative compounds in series 4 displayed selective toxicity to leukemia and colon cancer cell lines and were significantly more potent than the reference drug melphalan. Molecular modeling of representative compounds in both series 4 and the analogs, in which the configuration of the olefinic double bond was changed from E to Z (series 3), revealed that the torsion angles of the arylidene aryl rings and locations of the terminal arylaminocarbonyl groups may have contributed to the greater cytotoxic properties displayed in 3. Compounds 4c (3,4-dichlorophenylamino), d (4-methylphenylamino) and 5c (3,4-dichlorophenylamino), d (4-methylphenylamino) inhibited the activity of human N-myristoyltransferase by approximately 50% at concentrations of 50-100 microM. The compounds in series 4 and 5 were well tolerated in a short-term toxicity study in mice.  相似文献   
69.
Summary The presence and distribution of regulatory peptides in nerves and endocrine cells of the stomach, intestine and rectum of a urodele amphibian, the mudpuppy, Necturus maculosus, was studied immunohistochemically in sections or whole-mount preparations of the gut wall. The effect of the occurring peptides on gut motility was studied in isolated strip preparations of circular and longitudinal smooth muscle from different parts of the gut.Bombesin-, neurotensin-, substance P- and VIP-like immunoreactivity was present in abundant nerve fibres in the myenteric plexus of both stomach, intestine and rectum. Single fibres or bundles were present in the circular muscle layer and in a well-developed deep muscular plexus in the intestine and rectum. Immunoreactive nerve cells were found in the myenteric plexus of the stomach, intestine (neurotensin only) and rectum. Gastrin/CCK-like immunoreactivity was observed only in a few fibres in stomach and rectum.Endocrine cells containing bombesin-, met-enkephalin-, gastrin/CCK-, neurotensin-, somatostatin- or substance P- like immunoreactivity were present in the mucosa.The effect of bombesin was an inhibition of the rhythmic activity in circular muscle preparations and in longitudinal muscle from the rectum, while longitudinal muscle from the stomach usually responded with a weak increase in tonus. Neurotensin, like bombesin, was inhibitory on the spontaneous rhythmic activity of circular muscle throughout the gut, while the effect on longitudinal muscle was an increase in tonus. Met-enkephalin and substance P increased the tonus of all types of preparations, and often, in addition, initiated a rhythmic activity superimposed on this maintained tonus. VIP had a general inhibitory effect on the preparations, decreasing tonus and/or abolishing rhythmic activity.It is concluded that bombesin-, neurotensin-, substance P- and VIP-like peptides are present in nerves throughout the urodele gut and may have physiological functions in regulating the motility of the gut. The gastrin/CCK-like peptide present in nerves of the stomach and rectum may affect the function of these parts of the gut. The regulatory peptides present in endocrine cells may, perhaps with the exception of the somatostatin-like peptide, affect the motility humorally.  相似文献   
70.
As an infectious disease, tuberculosis (TB) is one of the major causes of death worldwide. Paleopathological and paleomicrobiological studies indicate a long standing association of the causative agent Mycobacterium tuberculosis and its human host. Since the occurrence and the epidemic spread of this pathogen seem to be closely linked to social and biological factors, it is of particular interest to understand better the role of TB during periods of social and nutritional change such as the Neolithic. In this study, 118 individuals from three sites in Saxony‐Anhalt (Germany) dating to the Linear Pottery Culture (5400–4800 BC) were examined macroscopically to identify TB related bone lesions. In two individuals, Pott's disease was detected. In addition, periosteal reactions of varying degrees and frequency were observed mainly along the neck of the ribs in 6.5% (2/31) of subadults and 35.1% (20/57) of adults, with one site standing out markedly. Rib lesions, however, are not specific indicators of TB as they can also be caused by other diseases; so additional investigations were undertaken using histology and micro‐CT scans to say more about the disease process. Supplementary molecular analyses indicate the presence of pathogens belonging to the Mycobacterium tuberculosis complex in individuals of all sites. Furthermore, we discuss the occurrence and spread of TB during the Neolithic with regard to nutritional aspects and possible risks of infection. The data presented provide important insights into the health status of Early Neolithic populations in Central Germany. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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