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61.
62.
Monique Lavialle Bernard Dumortier 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1990,166(6):785-789
Summary Analysis of the formal properties of photoperiodic systems has emphasized the importance of two discrete phases of nocturnal light sensitivity (the so-called points A and B) in a variety of taxa. This has been exemplified in the lepidopteran, Pieris brassicae, among other species, since the illumination of either of these phases in an otherwise short-day cycle (diapause inducing) gives rise to a long-day effect (development without diapause). In this species, the photoreceptor of diel cycles and the clock-counter system are very likely brain located. Using cytochrome oxidase activity as a marker of energy metabolism, a neuroanatomical base in the brain involved in long-day responses elicited by light at points A and B was investigated.Present results reveal that (i) the level of energy metabolism in the optic centres is connected with the photoperiodic process, and (ii) the two points A and B can be discriminated at a functional level. Referring to the formal models, the possible function of the optic centres, either as a photoreceptor or as a (part of the) clock, is discussed.Abbreviations
CO
cytochrome oxidase
-
OD
optical density
-
PTM
photoperiodic time measurement 相似文献
63.
Mohamed M Thabet Thomas WJ Huizinga Désirée M van der Heijde Annette HM van der Helm-van Mil 《Arthritis research & therapy》2009,11(5):1-9
Introduction
Evidence suggests that citrullinated fibrin(ogen) may be a potential in vivo target of anticitrullinated protein/peptide antibodies (ACPA) in rheumatoid arthritis (RA). We compared the diagnostic yield of three enzyme-linked immunosorbent assay (ELISA) tests by using chimeric fibrin/filaggrin citrullinated synthetic peptides (CFFCP1, CFFCP2, CFFCP3) with a commercial CCP2-based test in RA and analyzed their prognostic values in early RA.Methods
Samples from 307 blood donors and patients with RA (322), psoriatic arthritis (133), systemic lupus erythematosus (119), and hepatitis C infection (84) were assayed by using CFFCP- and CCP2-based tests. Autoantibodies also were analyzed at baseline and during a 2-year follow-up in 98 early RA patients to determine their prognostic value.Results
With cutoffs giving 98% specificity for RA versus blood donors, the sensitivity was 72.1% for CFFCP1, 78.0% for CFFCP2, 71.4% for CFFCP3, and 73.9% for CCP2, with positive predictive values greater than 97% in all cases. CFFCP sensitivity in RA increased to 80.4% without losing specificity when positivity was considered as any positive anti-CFFCP status. Specificity of the three CFFCP tests versus other rheumatic populations was high (> 90%) and similar to those for the CCP2. In early RA, CFFCP1 best identified patients with a poor radiographic outcome. Radiographic progression was faster in the small subgroup of CCP2-negative and CFFCP1-positive patients than in those negative for both autoantibodies. CFFCP antibodies decreased after 1 year, but without any correlation with changes in disease activity.Conclusions
CFFCP-based assays are highly sensitive and specific for RA. Early RA patients with anti-CFFCP1 antibodies, including CCP2-negative patients, show greater radiographic progression. 相似文献64.
An extra layer of complexity in the regulation of gene expression in bacteria is now apparent through previously unanticipated
roles of noncoding and antisense RNAs. 相似文献
65.
Ségalen M Johnston CA Martin CA Dumortier JG Prehoda KE David NB Doe CQ Bellaïche Y 《Developmental cell》2010,19(5):740-752
The Frizzled receptor and Dishevelled effector regulate mitotic spindle orientation in both vertebrates and invertebrates, but how Dishevelled orients the mitotic spindle is unknown. Using the Drosophila S2 cell "induced polarity" system, we find that Dishevelled cortical polarity is sufficient to orient the spindle and that Dishevelled's DEP domain mediates this function. This domain binds a C-terminal domain of Mud (the Drosophila NuMA ortholog), and Mud is required for Dishevelled-mediated spindle orientation. In Drosophila, Frizzled-Dishevelled planar cell polarity (PCP) orients the sensory organ precursor (pI) spindle along the anterior-posterior axis. We show that Dishevelled and Mud colocalize at the posterior cortex of pI, Mud localization at the posterior cortex requires Dsh, and Mud loss-of-function randomizes spindle orientation. During zebrafish gastrulation, the Wnt11-Frizzled-Dishevelled PCP pathway orients spindles along the animal-vegetal axis, and reducing NuMA levels disrupts spindle orientation. Overall, we describe a Frizzled-Dishevelled-NuMA pathway that orients division from Drosophila to vertebrates. 相似文献
66.
67.
Yoshifumi Kotani Shoji Shinkai Hiroshi Okamatsu Masamichi Toba Kishiko Ogawa Hiroto Yoshida Taro Fukaya Yoshinori Fujiwara Paulo HM Chaves Keiji Kakumoto Noriyuki Kohda 《Immunity & ageing : I & A》2010,7(1):1-11
Background
Immunoglobulin A (IgA) secretion in saliva decreases with age and may be the cause of increased vulnerability of the elderly to respiratory infections. The effect of oral intake of lactic acid bacteria on salivary secretory IgA (SIgA) in the elderly has not been reported. The objective of this study was to demonstrate the acceleration of salivary SIgA secretion by oral intake of Lactobacillus pentosus strain b240 (b240) in the elderly.Results
A total of 80 healthy elderly individuals were randomly allocated to either an intervention (i.e., b240) or a control (i.e., placebo) group. The elderly individuals in the b240 group were given a sterile water beverage (125 mL) containing heat-killed b240 (4 × 109 cells), while those in the placebo group were given only a sterile water beverage (125 mL); both groups received their respective beverages once daily for 12 weeks. Saliva was collected before initiation of the study and every 2 weeks thereafter. Saliva flow rate and SIgA concentration were determined, and the SIgA secretion rate was calculated. The mean salivary SIgA secretion rate in the b240 group steadily increased until week 4 (exhibiting a 20% elevation relative to that at week 0), and then remained stable until week 12. Changes in SIgA secretion rate over the intervention period were significantly greater in the b240 group than in the placebo group. The treatment groups exhibited no significant differences in adverse events.Conclusions
Oral intake of L. pentosus strain b240 for 12 weeks significantly accelerated salivary SIgA secretion, thereby indicating its potential utility in the improvement of mucosal immunity and resistance against infection in the elderly. 相似文献68.
Lauber U Dillenburger T Schollenberger M Müller HM Drochner W 《Mycotoxin Research》2000,16(2):166-169
To examine the biotransformation of Deoxynivalenol (DON) by the normal gut flora of pigs (in reliance on toxin-source) an in-vitro system was established. Suspensions of rectum contents from different treated animals were incubated with pure DON. Despite fast adaptation of microflora (Deepoxidation of DON) of animals fed wheat diet, no effects on reduced feed consumption and weight gain were seen. Even fast adaptation of microflora (lower intestine) couldn’t avoid DON-effects in vivo. 相似文献
69.
Joyce JBC van Beers Annemiek Willemze Jeroen J Jansen Gerard HM Engbers Martin Salden Jos Raats Jan W Drijfhout Annette HM van der Helm-van Mil Rene EM Toes Ger JM Pruijn 《Arthritis research & therapy》2013,15(5):R140
Introduction
Autoantibodies against citrullinated peptides/proteins (ACPA) are found in approximately 75% of the sera of patients with rheumatoid arthritis (RA). The RA-specific ACPA are frequently present prior to disease onset and their presence associates with a more erosive disease course. ACPA can therefore be used to aid the diagnosis and prognosis of RA. Recently, it became clear that ACPA are very heterogeneous, both in an individual patient and among different patients. The aim of this study was to investigate whether clinically meaningful ACPA profiles exist in early RA patients.Methods
Twenty citrullinated peptides and the corresponding non-citrullinated control peptides were immobilized on microarray sensor chips. Sera from 374 early arthritis patients were analyzed by surface plasmon resonance imaging (iSPR) of biomolecular interactions on the sensor chip.Results
Cluster analysis of the reactivities with the citrullinated peptides, after subtraction of the reactivities with the corresponding control peptides confirmed the heterogeneity of the ACPA response in RA and revealed 12 distinct ACPA profiles. The association of the 5 most frequent profiles with clinical features at diagnosis and during the disease course was examined, showing no statistically significant associations.Conclusions
Compared to the detection of ACPA in RA sera by CCP-based assays, ACPA profiling in early arthritis patients did not reveal associations with disease activity and progression scores. 相似文献70.
Maja Bulatovi? ?alasan Oscar FC van den Bosch Marjonne CW Creemers Martijn Custers Antonius HM Heurkens Jan Maarten van Woerkom Nico M Wulffraat 《Arthritis research & therapy》2013,15(6):R217