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31.
32.
K. Nones B. Knoch Y.E.M. Dommels G. Paturi C. Butts W.C. McNabb N.C. Roy 《Journal of applied microbiology》2009,107(2):557-566
Aim: To compare caecal microbiota from mdr1a –/– and wild type (FVB) mice to identify differences in the bacterial community that could influence the intestinal inflammation.
Methods and Results: Caecal microbiota of mdr1a–/– and FVB mice were evaluated at 12 and 25 weeks of age using denaturing gradient gel electrophoresis (DGGE) and quantitative real-time PCR. DGGE fingerprints of FVB and mdr1a –/– mice (with no intestinal inflammation) at 12 weeks revealed differences in the presence of DNA fragments identified as Bacteroides fragilis , B. thetaiotaomicron , B. vulgatus and an uncultured alphaproteobacterium. Escherichia coli and Acinetobacter sp. were only identified in DGGE profiles of mdr1a –/– mice at 25 weeks (with severe intestinal inflammation), which also had a lower number of total bacteria in the caecum compared with FVB mice at same age.
Conclusions: Differences found in the caecal microbiota of FVB and mdr1a–/– mice (12 weeks) suggest that the lack of Abcb1 transporters in intestinal cells due to the disruption of the mdr1a gene might lead to changes in the caecal microbiota. The altered microbiota along with the genetic defect could contribute to the development of intestinal inflammation in mdr1a –/– mice.
Significance and Impact of the Study: Differences in caecal microbiota of mdr1a–/– and FVB mice (12 weeks) suggest genotype specific colonization. The results provide evidence that Abcb1 transporters may regulate host interactions with commensal bacteria. Future work is needed to identify the mechanisms involved in this possible cross-talk between the host intestinal cells and microbiota. 相似文献
Methods and Results: Caecal microbiota of mdr1a
Conclusions: Differences found in the caecal microbiota of FVB and mdr1a
Significance and Impact of the Study: Differences in caecal microbiota of mdr1a
33.
Marion McNabb Emeka Chukwu Oluwayemisi Ojo Navendu Shekhar Christopher J. Gill Habeeb Salami Farouk Jega 《PloS one》2015,10(5)
BackgroundGiven the shortage of skilled healthcare providers in Nigeria, frontline community health extension workers (CHEWs) are commonly tasked with providing maternal and child health services at primary health centers. In 2012, we introduced a mobile case management and decision support application in twenty primary health centers in northern Nigeria, and conducted a pre-test/post-test study to assess whether the introduction of the app had an effect on the quality of antenatal care services provided by this lower-level cadre.MethodsUsing the CommCare mobile platform, the app dynamically guides CHEWs through antenatal care protocols and collects client data in real time. Thirteen health education audio clips are also embedded in the app for improving and standardizing client counseling. To detect changes in quality, we developed an evidence-based quality score consisting of 25 indicators, and conducted a total of 266 client exit interviews. We analyzed baseline and endline data to assess changes in the overall quality score as well as changes in the provision of key elements of antenatal care.ResultsOverall, the quality score increased from 13.3 at baseline to 17.2 at endline (p<0.0001), out of a total possible score of 25, with the most significant improvements related to health counseling, technical services provided, and quality of health education.ConclusionThese study results suggest that the introduction of a low-cost mobile case management and decision support application can spur behavior change and improve the quality of services provided by a lower level cadre of healthcare workers. Future research should employ a more rigorous experimental design to explore potential longer-term effects on client health outcomes. 相似文献
34.
Corbey et al. (2016) propose that the Acheulean handaxe was, at least in part, under genetic control. An alternative perspective is offered here, focusing on the nature of the Acheulean handaxe and the archaeological record, and re‐emphasizing their status as cultural artefacts. This is based on four main arguments challenging the proposals of Corbey et al. Firstly, handaxes do not have to track environmental variation to be a cultural artefact, given their role as a hand‐held butchery knife or multi‐purpose tool. Secondly, while handaxe shapes do cluster around a basic bauplan, there is also significant variability in the Acheulean handaxe record, characterized by site‐specific modal forms and locally expressed, short‐lived, idiosyncratic traits. Critically, this variability occurs in both time and space, is multi‐scalar, and does not appear to be under genetic control. Thirdly, handaxes were produced in social contexts, within which their makers grew up exposed to the sights and sounds of artefact manufacture. Finally, the localized absences of handaxes at different times and places in the Lower Paleolithic world is suggestive of active behavioral choices and population dynamics rather than genetic controls. 相似文献
35.
M. Rafiqul I. Khan Aldo Ceriotti Linda Tabe Arun Aryan Warren McNabb Andrew Moore Stuart Craig Donald Spencer Thomas J. V. Higgins 《Transgenic research》1996,5(3):179-185
A gene encoding a sulphur-rich, sunflower seed albumin (23% cysteine plus methionine) was modified to contain the promoter for the 35S RNA of cauliflower mosaic virus, in order to obtain leaf expression in transgenic plants. In addition, a sequence encoding an endoplasmic reticulum-retention signal was added to the 3 end of the coding region so as to stabilize the protein by diverting it away from the vacuole. The modified gene was introduced into subterranean clover (T. subterraneum L.) and its expression was detected by northern and western blots and by immunogold localization. The albumin was accumulated in the lumen of the endoplasmic reticulum, and, among six independent, transformed lines, it accumulated in the leaves of T0 transgenic plants at varying levels up to 0.3% of the total extractable protein. The level of accumulation of the sunflower albumin increased with increasing leaf age, and in the older leaves of the most highly expressing plants of the T1 generation it reached 1.3% of total extractable protein. Expression of the SSA gene was stable in the first and second generation progeny. These results indicate that there is potential for significantly improving the nutritional value of subterranean clover for ruminant animals such as sheep by expressing genes that code for sulphur-rich, rumen-stable proteins in leaves. 相似文献
36.
37.
Paired sequence difference in ribosomal RNAs: evolutionary and phylogenetic implications 总被引:12,自引:1,他引:11
Ribosomal RNAs have secondary structures that are maintained by internal
Watson-Crick pairing. Through analysis of chordate, arthropod, and plant 5S
ribosomal RNA sequences, we show that Darwinian selection operates on these
nucleotide sequences to maintain functionally important secondary
structure. Insect phylogenies based on nucleotide positions involved in
pairing and the production of secondary structure are incongruent with
those constructed on the basis of positions that are not. Furthermore,
phylogeny reconstruction using these nonpairing bases is concordant with
other, morphological data.
相似文献
38.
M E McNabb 《CMAJ》1984,131(6):589-592
Techniques that help patients stop smoking should also reduce their exposure to agents such as nicotine. The mean plasma nicotine levels in 50 subjects while they were still smoking and then while they were chewing pieces of gum containing either 2 or 4 mg of nicotine over a 12-week period of abstinence were 35, 9 and 23 ng/mL (217, 56 and 143 nmol/L) respectively. A small number of subjects given an unlimited supply of gum used 14 to 24 pieces of 4-mg gum daily and had plasma nicotine levels exceeding the levels achieved while smoking. There were no acute symptoms necessitating medical intervention associated with these excessive levels. Side effects were uncommon and usually controllable. When simple dosage rules are followed people who chew nicotine gum for a few months to stop smoking lower their exposure to nicotine. 相似文献
39.
The effect of various phenols on the conversion of [4 -14C]estradiol to water-soluble products by estrogen-induced uterine peroxidase (EC 1.11.1.7) has been investigated. Evidence was provided that those phenols which enhanced the oxidation of estradiol exerted their effect by activating peroxidase or protecting the enzyme from inactivation by the products of the reaction rather than by inhibiting the breakdown of hydrogen peroxide by catalase (EC 1.11.1.6). It has also been shown that tyrosine acted both as an activator of uterine peroxidase and as a water-soluble acceptor for the metabolites of estradiol. The ability of tyrosyl peptides to form conjugates with estradiol was influenced by the other amino acids and decreased with the number of adjacent tyrosyl residues. 相似文献
40.
Previous research on smart phone use while driving has primarily focused on phone calls and texting. Drivers are now increasingly using their phone for other activities during driving, in particular social media, which have different cognitive demands. The present study compared the effects of four different smart phone tasks on car-following performance in a driving simulator. Phone tasks were chosen that vary across two factors: interaction medium (text vs image) and task pacing (self-paced vs experimenter-paced) and were as follows: Text messaging with the experimenter (text/other-paced), reading Facebook posts (text/self-paced), exchanging photos with the experimenter via Snapchat (image, experimenter -paced), and viewing updates on Instagram (image, experimenter -paced). Drivers also performed a driving only baseline. Brake reaction times (BRTs) were significantly greater in the text-based conditions (Mean = 1.16 s) as compared to both the image-based conditions (Mean = 0.92 s) and the baseline (0.88 s). There was no significant difference between BRTs in the image-based and baseline conditions and there was no significant effect of task-pacing. Similar results were obtained for Time Headway variability. These results are consistent with the picture superiority effect found in memory research and suggest that image-based interfaces could provide safer ways to “stay connected” while driving than text-based interfaces. 相似文献