195 research outputs found
Knowledge of fertility and perception of fertility treatment among adults with sickle cell disease (KNOW FERTILITY)
IntroductionThis study assessed fertility knowledge in adults with sickle cell disease using the Cardiff Fertility Knowledge Scale and Fertility Treatment Perception Survey and compared knowledge scores in respondents with sickle cell disease to previously reported unaffected cohorts.MethodsThis cross-sectional study surveyed adults over age 18 with sickle cell disease at an adult sickle cell disease center using a 35-question survey addressing infertility risk factor knowledge and perceptions of fertility treatment. Analyses included summary statistics for continuous and categorical variables, univariate linear regression, and Mann-Whitney U tests for group comparisons of Fertility Knowledge Scale scores. Fertility Treatment Perception Survey scores were measured by medians of the two positive statements and four negative statements to generate separate positive and negative treatment belief scores. Statistical significance was set at pβ<β0.05 for all analyses.ResultsNinety-two respondents (71 female, 21 male) with median age of 32 years (IQR: 25.0, 42.5) completed the survey between October 2020-May 2021. Sixty-five percent of respondents reported taking sickle cell disease treatment and 18% reported refusing at least one sickle cell disease treatment due to fertility concerns. The mean Fertility Knowledge Score was 49% (SD: 5.2), lower than reported in an international cohort (57% vs. 49%, pβ=β0.001), and higher than in a cohort of reproductive-aged Black women in the USA (49% vs. 38%, pβ=β0.001). Less than 50% of respondents correctly identified common infertility risk factors including sexually transmitted infections, advanced age, and obesity. Mean positive fertility perception score was 3 (IQR 3, 4), and negative fertility perception score was 3.5 (IQR 3, 4). Factors associated with agreement with negative fertility perception statements included: trying to conceive, refusing sickle cell disease treatment, and undergoing fertility treatment.DiscussionOpportunities exist to improve knowledge of infertility risk factors among adults with sickle cell disease. This study raises the possibility that nearly one in five adults with sickle cell disease refuse SCD treatment or cure due to infertility concerns. Education about common infertility risks factors needs to be addressed alongside disease- and treatment- associated fertility risks
Symbiotic modeling: Linguistic Anthropology and the promise of chiasmus
Reflexive observations and observations of reflexivity: such agendas are by now standard practice in anthropology. Dynamic feedback loops between self and other, cause and effect, represented and representamen may no longer seem surprising; but, in spite of our enhanced awareness, little deliberate attention is devoted to modeling or grounding such phenomena. Attending to both linguistic and extra-linguistic modalities of chiasmus (the X figure), a group of anthropologists has recently embraced this challenge. Applied to contemporary problems in linguistic anthropology, chiasmus functions to highlight and enhance relationships of interdependence or symbiosis between contraries, including anthropologyβs four fields, the nature of human being and facets of being human
Selection of optimal reference genes for normalization in quantitative RT-PCR
<p>Abstract</p> <p>Background</p> <p>Normalization in real-time qRT-PCR is necessary to compensate for experimental variation. A popular normalization strategy employs reference gene(s), which may introduce additional variability into normalized expression levels due to innate variation (between tissues, individuals, etc). To minimize this innate variability, multiple reference genes are used. Current methods of selecting reference genes make an assumption of independence in their innate variation. This assumption is not always justified, which may lead to selecting a suboptimal set of reference genes.</p> <p>Results</p> <p>We propose a robust approach for selecting optimal subset(s) of reference genes with the smallest variance of the corresponding normalizing factors. The normalizing factor variance estimates are based on the estimated unstructured covariance matrix of all available candidate reference genes, adjusting for all possible correlations. Robustness is achieved through bootstrapping all candidate reference gene data and obtaining the bootstrap upper confidence limits for the variances of the log-transformed normalizing factors. The selection of the reference gene subset is optimized with respect to one of the following criteria: (A) to minimize the variability of the normalizing factor; (B) to minimize the number of reference genes with acceptable upper limit on variability of the normalizing factor, (C) to minimize the average rank of the variance of the normalizing factor. The proposed approach evaluates all gene subsets of various sizes rather than ranking individual reference genes by their stability, as in the previous work. In two publicly available data sets and one new data set, our approach identified subset(s) of reference genes with smaller empirical variance of the normalizing factor than in subsets identified using previously published methods. A small simulation study indicated an advantage of the proposed approach in terms of sensitivity to identify the true optimal reference subset in the presence of even modest, especially negative correlation among the candidate reference genes.</p> <p>Conclusions</p> <p>The proposed approach performs comprehensive and robust evaluation of the variability of normalizing factors based on all possible subsets of candidate reference genes. The results of this evaluation provide flexibility to choose from important criteria for selecting the optimal subset(s) of reference genes, unless one subset meets all the criteria. This approach identifies gene subset(s) with smaller variability of normalizing factors than current standard approaches, particularly if there is some nontrivial innate correlation among the candidate genes.</p
Effects of syntactic context on eye movements during reading
Previous research has demonstrated that properties of a currently fixated word
and of adjacent words influence eye movement control in reading. In contrast to
such local effects, little is known about the global effects on eye movement
control, for example global adjustments caused by processing difficulty of
previous sentences. In the present study, participants read text passages in
which voice (active vs. passive) and sentence structure (embedded vs.
non-embedded) were manipulated. These passages were followed by identical target
sentences. The results revealed effects of previous sentence structure on gaze
durations in the target sentence, implying that syntactic properties of
previously read sentences may lead to a global adjustment of eye movement
control
Voltage-gated Na<sup>+</sup> channel activity increases colon cancertranscriptional activity and invasion via persistent MAPK signaling
Β© 2015 Macmillan Publishers Limited. All rights reserved. Functional expression of voltage-gated Na+ channels (VGSCs) has been demonstrated in multiple cancer cell types where channel activity induces invasive activity. The signaling mechanisms by which VGSCs promote oncogenesis remain poorly understood. We explored the signal transduction process critical to VGSC-mediated invasion on the basis of reports linking channel activity to gene expression changes in excitable cells. Coincidentally, many genes transcriptionally regulated by the SCN5A isoform in colon cancer have an over-representation of cis-acting sites for transcription factors phosphorylated by ERK1/2 MAPK. We hypothesized that VGSC activity promotes MAPK activation to induce transcriptional changes in invasion-related genes. Using pharmacological inhibitors/activators and siRNA-mediated gene knockdowns, we correlated channel activity with Rap1-dependent persistent MAPK activation in the SW620 human colon cancer cell line. We further demonstrated that VGSC activity induces downstream changes in invasion-related gene expression via a PKA/ERK/c-JUN/ELK-1/ETS-1 transcriptional pathway. This is the first study illustrating a molecular mechanism linking functional activity of VGSCs to transcriptional activation of invasion-related genes
Detection of cytokeratins 19/20 and guanylyl cyclase C in peripheral blood of colorectal cancer patients
The clinical significance of detecting supposed tumour cell-derived mRNA transcripts in blood using the polymerase chain reaction (PCR) remains unclear. We have used a fully quantitative 5β²-nuclease RT-PCR assay to screen for the expression of cytokeratins (ck) 19 and 20 and guanylyl cyclase C (GCC) in the peripheral blood of 21 healthy controls and 27 colorectal cancer patients. Expression of cytokeratin 19 and 20 mRNA was detected in 30% and 100% of samples, respectively, taken from healthy volunteers. There was no apparent difference in ck19 and ck20 mRNA transcription levels between controls and patients, or between patients with different Dukes' stages. While GCC mRNA was detected in only 1/21 control samples, it was expressed in approximately 80% of patients, although again there was no correlation between GCC levels and disease stage. Transcription levels of all three markers varied considerably between samples, even between samples taken from the same person at different times. We conclude that neither ck19 nor ck20 are reliable markers for the detection of colon epithelial cells in peripheral blood and that an evaluation of the usefulness of GCC awaits further longitudinal studies. Β© 1999 Cancer Research Campaig
New Insights in the Contribution of Voltage-Gated Nav Channels to Rat Aorta Contraction
BACKGROUND: Despite increasing evidence for the presence of voltage-gated Na(+) channels (Na(v)) isoforms and measurements of Na(v) channel currents with the patch-clamp technique in arterial myocytes, no information is available to date as to whether or not Na(v) channels play a functional role in arteries. The aim of the present work was to look for a physiological role of Na(v) channels in the control of rat aortic contraction. METHODOLOGY/PRINCIPAL FINDINGS: Na(v) channels were detected in the aortic media by Western blot analysis and double immunofluorescence labeling for Na(v) channels and smooth muscle alpha-actin using specific antibodies. In parallel, using real time RT-PCR, we identified three Na(v) transcripts: Na(v)1.2, Na(v)1.3, and Na(v)1.5. Only the Na(v)1.2 isoform was found in the intact media and in freshly isolated myocytes excluding contamination by other cell types. Using the specific Na(v) channel agonist veratridine and antagonist tetrodotoxin (TTX), we unmasked a contribution of these channels in the response to the depolarizing agent KCl on rat aortic isometric tension recorded from endothelium-denuded aortic rings. Experimental conditions excluded a contribution of Na(v) channels from the perivascular sympathetic nerve terminals. Addition of low concentrations of KCl (2-10 mM), which induced moderate membrane depolarization (e.g., from -55.9+/-1.4 mV to -45.9+/-1.2 mV at 10 mmol/L as measured with microelectrodes), triggered a contraction potentiated by veratridine (100 microM) and blocked by TTX (1 microM). KB-R7943, an inhibitor of the reverse mode of the Na(+)/Ca(2+) exchanger, mimicked the effect of TTX and had no additive effect in presence of TTX. CONCLUSIONS/SIGNIFICANCE: These results define a new role for Na(v) channels in arterial physiology, and suggest that the TTX-sensitive Na(v)1.2 isoform, together with the Na(+)/Ca(2+) exchanger, contributes to the contractile response of aortic myocytes at physiological range of membrane depolarization
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