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81.
While it is generally assumed that Indo-Pacific reefs are not widely affected by diseases, limited data suggest a number of diseases and syndromes that appear to differ from those currently under study in the Caribbean. This report presents the results of a baseline survey of coral diseases in 2 regions in the Philippines: the Central Visayas and the Lingayen Gulf. Mean prevalence for all diseases observed was 8.3 +/- 1.2% (mean +/- SE; n = 8 reefs), with Central Visayas reefs showing higher disease prevalence (11.6 +/- 2.8%; n = 4 reefs) than those of Lingayen Gulf (5.1 +/- 1.4%; n = 4 reefs). Five diseases and syndromes were described; 3 of these-Porites ulcerative white spot disease (PUWS) (prevalence = 8.96 +/- 2.2%), tumors (prevalence = 1.0 +/- 0.5%) and pigmentation response (prevalence = 0.5 +/- 0.2%)--occurred frequently in both regions and targeted the genus Porites. Correlation between disease prevalence and number of Porites colonies was fairly strong (r2 = 43.4), though not significant, and no correlation was seen between prevalence and either the amount or diversity of hard coral. Porites is a major reef-builder in the Indo-Pacific comprising 30% of hard coral colonies on our surveyed reefs, and is generally thought to be a hardy, long-lived genus. Diseases targeting this robust group present an as yet unquantified risk to Philippine reefs and could result in major changes in reef structure.  相似文献   
82.
Meiotic studies are carried out in 7 species of Eryngium L. (Saniculoideae, Apiaceae), belonging to both sections Foetida and Panniculata. The chromosome number of E. dorae Norm. (n=8) (Foetida) is reported for the first time, while the gametic chromosome number of E. nudicaule Lam. (n=7) (Foetida) and E. eburneum Decne. (n=8), E. horridum Malme (n=8), E. megapotamicum Malme (n=16), E. mesopotamicum Pedersen (n=24), and E. pandanifolium Cham. et Schlechtd. (n=24) (all belonging to Panniculata) is confirmed in several natural populations. Whereas in section Foetida all species are diploids and two basic chromosome numbers are present (x=8 and x=7), in section Panniculata all species are x=8 but there are three different ploidy levels (diploid, tetraploid, hexaploid). This study reveals that meiosis in all species is normal, with regular bivalent formation in all studied cells. Furthermore, the pollen stainability is above 80% in all cases. These data, together with the previous karyotype analyses, will contribute to the clarification of the relationships between members of both sections, where different mechanisms of speciation have been postulated.  相似文献   
83.
The leukocyte integrin alphaMbeta2 (Mac-1) is a multiligand receptor that mediates a range of adhesive reactions of leukocytes during the inflammatory response. This integrin binds the coagulation protein fibrinogen providing a key link between thrombosis and inflammation. However, the mechanism by which alphaMbeta2 binds fibrinogen remains unknown. Previous studies indicated that a model in which two fibrinogen gammaC domain sequences, P1 (gamma190-202) and P2 (gamma377-395), serve as the alphaMbeta2 binding sites cannot fully account for recognition of fibrinogen by integrin. Here, using surface plasmon resonance, we examined the interaction of the ligand binding alphaMI-domain of alphaMbeta2 with the D fragment of fibrinogen and showed that this ligand is capable of associating with several alphaMI-domain molecules. To localize the alternative alphaMI-domain binding sites, we screened peptide libraries covering the complete sequences of the gammaC and betaC domains, comprising the majority of the D fragment structure, for alphaMI-domain binding. In addition to the P2 and P1 peptides, the alphaMI-domain bound to many other sequences in the gammaC and betaC scans. Similar to P1 and P2, synthetic peptides derived from gammaC and betaC were efficient inhibitors of alphaMbeta2-mediated cell adhesion and were able to directly support adhesion suggesting that they contain identical recognition information. Analyses of recognition specificity using substitutional peptide libraries demonstrated that the alphaMI-domain binding depends on basic and hydrophobic residues. These findings establish a new model of alphaMbeta2 binding in which the alphaMI-domain interacts with multiple sites in fibrinogen and has the potential to recognize numerous sequences. This paradigm may have implications for mechanisms of promiscuity in ligand binding exhibited by integrin alphaMbeta2.  相似文献   
84.
Members of the miR‐200 family are critical gatekeepers of the epithelial state, restraining expression of pro‐mesenchymal genes that drive epithelial–mesenchymal transition (EMT) and contribute to metastatic cancer progression. Here, we show that miR‐200c and another epithelial‐enriched miRNA, miR‐375, exert widespread control of alternative splicing in cancer cells by suppressing the RNA‐binding protein Quaking (QKI). During EMT, QKI‐5 directly binds to and regulates hundreds of alternative splicing targets and exerts pleiotropic effects, such as increasing cell migration and invasion and restraining tumour growth, without appreciably affecting mRNA levels. QKI‐5 is both necessary and sufficient to direct EMT‐associated alternative splicing changes, and this splicing signature is broadly conserved across many epithelial‐derived cancer types. Importantly, several actin cytoskeleton‐associated genes are directly targeted by both QKI and miR‐200c, revealing coordinated control of alternative splicing and mRNA abundance during EMT. These findings demonstrate the existence of a miR‐200/miR‐375/QKI axis that impacts cancer‐associated epithelial cell plasticity through widespread control of alternative splicing.  相似文献   
85.
BackgroundNon-invasive ventilation (NIV) tolerance is a key factor of NIV success. Hence, numerous sedative pharmacological or non-pharmacological strategies have been assessed to improve NIV tolerance. Music therapy in various health care settings has shown beneficial effects. In invasively ventilated critical care patients, encouraging results of music therapy on physiological parameters, anxiety, and agitation have been reported. We hypothesize that a musical intervention improves NIV tolerance in comparison to conventional care. We therefore question the potential benefit of a receptive music session administered to patients by trained caregivers (“musical intervention”) to enhance acceptance and tolerance of NIV.Methods/designWe conduct a prospective, three-center, open-label, three-arm randomized trial involving patients in the intensive care unit (ICU) who require NIV, as assessed by the treating physician. Participants are allocated to a “musical intervention” arm (“musical intervention” applied during all NIV sessions), to a “sensory deprivation” arm (sight and hearing isolation during all NIV sessions), or to the control group. The primary endpoint is the change in respiratory comfort (measured with a digital visual scale) before the initiation and after 30 minutes of the first NIV session. The evaluation of the primary endpoint is performed blindly from the treatment group. Secondary endpoints include changes in respiratory and cardiovascular parameters during NIV sessions, the percentage of patients requiring endotracheal intubation, day-90 anxiety/depression and health-related quality of life, post-trauma stress induced by NIV, and the overall assessment of NIV.The follow-up for each participant is 90 days. We expect to randomize a total of 99 participants.DiscussionAs music intervention is a simple and easy-to-implement non-pharmacological technique, efficacious in reducing anxiety in critically ill patients, it appeared logical to assess its efficacy in NIV, one of the most stressful techniques used in the ICU. Patient centeredness was crucial in choosing the outcomes assessed.

Trial registration

ClinicalTrials.gov: NCT02265458. Registered on 25 August 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1574-z) contains supplementary material, which is available to authorized users.  相似文献   
86.
Octopamine, one of the main insect biogenic amines, plays an important role in the control of fitness in Drosophila melanogaster Meigen. The present study examines the effects of a null mutation of the gene of the insulin‐like receptor substrate (chico), in the heterozygous state, on octopamine metabolism, heat stress resistance and fecundity of D. melanogaster. A rise in the activity of one of the key enzymes of octopamine synthesis, tyrosine decarboxylase, as well as that of an enzyme of its degradation, octopamine‐dependent N‐acetyl transferase, is observed in chico1/+ females. It is also found that the resistance to heat stress is decreased and fecundity is reduced dramatically in chico1/+ flies. Such changes in these parameters in D. melanogaster females result from a rise in octopamine titre, which suggests that chico affects the octopamine level by regulating the activity of tyrosine decarboxylase.  相似文献   
87.
88.
Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is not available and vector control is essential to minimize dengue incidence. This report deals with the larvicidal activity of lectins isolated from Myracrodruon urundeuva bark (MuBL) and heartwood (MuHL). The lectins were isolated by ammonium sulphate treatment of crude extracts followed by chromatography on chitin. MuBL and MuHL were evaluated by electrophoresis under native (PAGE) and denaturing conditions (SDS-PAGE). Carbohydrate specificity of lectins was evaluated by hemagglutinating activity (HA) inhibition assay using N-acetyl-d-glucosamine and by affinity chromatography on N-acetyl-D-glucosamine immobilized in agarose gel. Larvicidal activity against A. aegypti was investigated with the extracts, salt fractions and isolated lectins. MuBL and MuHL were characterized by PAGE as basic proteins of molecular masses of 14.0 and 14.4 kDa, respectively. The interaction of lectins with N-acetylglucosamine was detected by inhibition of HA by monosaccharide and lectin adsorptions on N-acetyl-D-glucosamine matrix. All M. urundeuva preparations promoted larvae mortality. LC16, LC50 and LC84 values of 0.077, 0.125, 0.173 for MuBL and 0.03, 0.04 and 0.05 mg/mL for MuHL were obtained. To our knowledge this is the first report of larvicidal activity of lectins against A. aegypti.  相似文献   
89.
L-type calcium currents (ICa) are influenced by changes in extracellular chloride, but sites of anion effects have not been identified. Our experiments showed that CaV1.2 currents expressed in HEK293 cells are strongly inhibited by replacing extracellular chloride with gluconate or perchlorate. Variance-mean analysis of ICa and cell-attached patch single channel recordings indicate that gluconate-induced inhibition is due to intracellular anion effects on Ca2+ channel open probability, not conductance. Inhibition of CaV1.2 currents produced by replacing chloride with gluconate was reduced from ∼75%–80% to ∼50% by omitting β subunits but unaffected by omitting α2δ subunits. Similarly, gluconate inhibition was reduced to ∼50% by deleting an α1 subunit N-terminal region of 15 residues critical for β subunit interactions regulating open probability. Omitting β subunits with this mutant α1 subunit did not further diminish inhibition. Gluconate inhibition was unchanged with expression of different β subunits. Truncating the C terminus at AA1665 reduced gluconate inhibition from ∼75%–80% to ∼50% whereas truncating it at AA1700 had no effect. Neutralizing arginines at AA1696 and 1697 by replacement with glutamines reduced gluconate inhibition to ∼60% indicating these residues are particularly important for anion effects. Expressing CaV1.2 channels that lacked both N and C termini reduced gluconate inhibition to ∼25% consistent with additive interactions between the two tail regions. Our results suggest that modest changes in intracellular anion concentration can produce significant effects on CaV1.2 currents mediated by changes in channel open probability involving β subunit interactions with the N terminus and a short C terminal region.  相似文献   
90.
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