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71.
Juliana R Martins Francis MF Nunes Alexandre S Cristino Zilá LP Simões Márcia MG Bitondi 《BMC molecular biology》2010,11(1):23
Background
Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens. 相似文献72.
Eduardo?S?SilvaEmail author Gerard?J?Schoone Celia?MF?Gontijo Reginaldo?P?Brazil Raquel?S?Pacheco Henk?DFH?Schallig 《Kinetoplastid biology and disease》2005,4(1):4
Background
The direct agglutination test (DAT) has proved to be a very important sero-diagnostic tool combining high levels of intrinsic validity and ease of performance. Otherwise, fast agglutination screening test (FAST) utilises only one serum dilution making the test very suitable for the screening of large populations. 相似文献73.
Status of complete proteome analysis by mass spectrometry: SILAC labeled yeast as a model system 总被引:4,自引:1,他引:4
Background
Mass spectrometry has become a powerful tool for the analysis of large numbers of proteins in complex samples, enabling much of proteomics. Due to various analytical challenges, so far no proteome has been sequenced completely. O'Shea, Weissman and co-workers have recently determined the copy number of yeast proteins, making this proteome an excellent model system to study factors affecting coverage. 相似文献74.
Dilraj Singh Sokhi Chantal Oxenham Rebecca Coates Mhairi Forbes Nadi K. Gupta Daniel J. Blackburn 《PloS one》2015,10(9)
Background
UK National Guidelines (UKNG) advise HIV testing in clinically indicated neurological presentations. We audited the impact of our practical strategies to increase uptake of HIV testing at a regional acute neurology admissions unit.Methods
We audited HIV testing in 4 periods over 2 years: before we designed a UKNG-based “HIV testing in Neurology” protocol (“pre-protocol”); after dissemination of the protocol alone (“post-protocol”); post-protocol dissemination combined with both a tailored departmental admissions clerking proforma to prompt for HIV testing & consenting, and regular focussed tutorials to doctors on HIV testing in neurological patients (“post-proforma”); and finally one year after the post-proforma period (“+1 year”). We also looked at the total number of HIV tests sent from the unit during the two-year period. We assessed significance using Fisher’s exact test.Results
47.8% of all acute neurology non-stroke admissions were eligible for HIV testing during all the audit periods. Testing rates were as follows: pre-protocol 21.9%; post-protocol 36.6%; post-proforma 83.3%; and at +1 year 65.4% (p<0.05 for both post-protocol and +1 year when compared to pre-protocol). Documentation of consent for HIV testing improved from 25% to 67.6% with the HIV-tailored clerking proforma. The total number of HIV tests requested from the unit doubled in the post-proforma period compared to pre-protocol (p<0.05).Conclusion
In conclusion: the combination of an HIV testing protocol, a tailored departmental clerking proforma and regular focussed teaching to doctors on indications for HIV testing led to a sustained increase in HIV testing uptake in our regional acute neurology admissions unit. 相似文献75.
Background
Gα16 can activate phospholipase Cβ (PLCβ) directly like Gαq. It also couples to tetratricopeptide repeat 1 (TPR1) which is linked to Ras activation. It is unknown whether PLCβ and TPR1 interact with the same regions on Gα16. Previous studies on Gαq have defined two minimal clusters of amino acids that are essential for the coupling to PLCβ. Cognate residues in Gα16 might also be essential for interacting with PLCβ, and possibly contribute to TPR1 interaction and other signaling events.Results
Alanine mutations were introduced to the two amino acid clusters (246–248 and 259–260) in the switch III region and α3 helix of Gα16. Regulations of PLCβ and STAT3 were partially weakened by each cluster mutant. A mutant harboring mutations at both clusters generally produced stronger suppressions. Activation of Jun N-terminal kinase (JNK) by Gα16 was completely abolished by mutating either clusters. Contrastingly, phosphorylations of extracellular signal-regulated kinase (ERK) and nuclear factor κB (NF-κB) were not significantly affected by these mutations. The interactions between the mutants and PLCβ2 and TPR1 were also reduced in co-immunoprecipitation assays. Coupling between G16 and different categories of receptors was impaired by the mutations, with the effect of switch III mutations being more pronounced than those in the α3 helix. Mutations of both clusters almost completely abolished the receptor coupling and prevent receptor-induced Gβγ release.Conclusion
The integrity of the switch III region and α3 helix of Gα16 is critical for the activation of PLCβ, STAT3, and JNK but not ERK or NF-κB. Binding of Gα16 to PLCβ2 or TPR1 was reduced by the mutations of either cluster. The same region could also differentially affect the effectiveness of receptor coupling to G16. The studied region was shown to bear multiple functionally important roles of G16. 相似文献76.
Accurate pitch perception of harmonic complex tones is widely believed to rely on temporal fine structure information conveyed by the precise phase-locked responses of auditory-nerve fibers. However, accurate pitch perception remains possible even when spectrally resolved harmonics are presented at frequencies beyond the putative limits of neural phase locking, and it is unclear whether residual temporal information, or a coarser rate-place code, underlies this ability. We addressed this question by measuring human pitch discrimination at low and high frequencies for harmonic complex tones, presented either in isolation or in the presence of concurrent complex-tone maskers. We found that concurrent complex-tone maskers impaired performance at both low and high frequencies, although the impairment introduced by adding maskers at high frequencies relative to low frequencies differed between the tested masker types. We then combined simulated auditory-nerve responses to our stimuli with ideal-observer analysis to quantify the extent to which performance was limited by peripheral factors. We found that the worsening of both frequency discrimination and F0 discrimination at high frequencies could be well accounted for (in relative terms) by optimal decoding of all available information at the level of the auditory nerve. A Python package is provided to reproduce these results, and to simulate responses to acoustic stimuli from the three previously published models of the human auditory nerve used in our analyses. 相似文献
77.
Biomass of the fungal pathogen Botrytis fabae in liquid culture amended with two chemotypes of the essential oil of basil, Ocimum basilicum, was reduced significantly at concentrations of 50 ppm or less. The methyl chavicol chemotype oil increased the activity of the polyamine biosynthetic enzyme S-adenosylmethionine decarboxylase (AdoMetDC), but polyamine concentrations were not significantly altered. In contrast, the linalol chemotype oil decreased AdoMetDC activity in B. fabae, although again polyamine concentrations were not altered significantly. However activities of the polyamine catabolic enzymes diamine oxidase (DAO) and polyamine oxidase (PAO) were increased significantly in B. fabae grown in the presence of the essential oil of the two chemotypes. It is suggested that the elevated activities of DAO and PAO may be responsible, in part, for the antifungal effects of the basil oil, possibly via the generation of hydrogen peroxide and the subsequent triggering of programmed cell death. 相似文献
78.
Mel W is a second generation anionic organic arsenical which is filaricidal but has sporadic and unacceptable lethal side effects. Eight new cationic derivatives have now been synthesized in an attempt to avoid the side effects and have been examined for their effects upon adult Brugia pahangi in Meriones unguiculatus. They were all shown to be potent filaricides and the two best compounds, Mel Ga and Mel Cy, were at least 95% effective in killing adult B. pahangi at 5 X 3.13 mg/kg when injected subcutaneously. 相似文献
79.
80.
The purpose of this article is to present new oral health data from Neolithic An Son, southern Vietnam, in the context of (1) a reassessment of published data on other Neolithic, Bronze, and Iron Age Southeast Asian dental series, and (2) predictions of the Neolithic Demographic Transition (NDT). To this end, frequencies for three oral conditions (caries, antemortem tooth loss, and alveolar lesions) were investigated for seven Southeast Asian adult dental series from Thailand and Vietnam with respect to time period, age‐at‐death and sex. A clear pattern of elevated rates for oral disease in the Neolithic followed by a marked improvement in oral health during the Bronze and Iron Ages was observed. Moreover, rates of caries and antemortem tooth loss for females were almost without exception higher than that for males in all samples. The consensus view among Southeast Asian bioarchaeologists that oral health did not decline with the adoption/intensification of agriculture in Southeast Asia, can no longer be supported. In light of evidence for (1) the low cariogenicity of rice; (2) the physiological predisposition of females (particularly when pregnant) to poorer oral health; and (3) health predictions of the NDT model with respect to elevated levels of fertility, the most plausible chief explanation for the observed patterns in oral health in Southeast Asia is increased levels of fertility during the Neolithic, followed by a decline in fertility during the subsequent Bronze and Iron Ages. Am J Phys Anthropol 152:197–208, 2013. © 2013 Wiley Periodicals, Inc. 相似文献