2,696 research outputs found
An Experimental Study of Techniques to Improve Response Rates of Mail Questionnarie
The study examined (a) which single technique (cover letter sponsorship, personalization, anonymity, or appeal) is most effective in increasing response rates with mail questionnaires, and (b) which combination of these selected techniques is most effective in increasing such response rates. Questionnaires concerning faculty evaluation were sent to a national sample of professors.
The present study found that identification of a university as the sponsor of the survey resulted in a significantly higher response rate than that obtained when the survey was sponsored by a private research institute. There was a significant increase in response rates when the cover letter was personalized, as opposed to an unpersonalized form letter. There were no significant differences in response rates attributable to (a) wether respondents were assured anonymity, and (b) the type of appeal used in the cover letter (personal or professional appeal). No significant interactions were found among any of the four techniques investigated. It was concluded from this study that judicious selection of the survey sponsor and use of cover letter personalization can improve the response rates of a mail questionnaire significantly, at least with the type of population and questionnaire significantly, at least with the type of population and questionnaire topic used in this study
The Relationship Between Students\u27 Evaluation of Faculty and Students\u27 Grades
The study examined (a) the relationship between the grade students expect to receive and their evaluation rating, (b) the relationship between students\u27 prior cumulative GPA and their evaluation rating, and (c) to what extent do other variables account for the relationship between grade and evaluation rating.
The present study found a significant, consistent relationship between students\u27 expected grades and their evaluation ratings of professor. The relationship between students\u27 cumulative GPA and ratings is negligible and should not be considered an important score of bias. The implication of this study is that great caution should be exercised when using such ratings to make key career decisions about professors
Ciliated muconodular papillary tumor of the lung: The risk of false-positive diagnosis in frozen section
AbstractCiliated muconodular papillary tumor (CMPT) is newly-defined low-grade malignant tumor, characterized as papillary tumor consisting of ciliated columnar, goblet, and basal cells. We present one case of pulmonary peripheral neoplasm misdiagnosed as mucinous adenocarcinoma. Pathologic findings showed, centrally, cystic papillary growth consisting of ciliated columnar, goblet, and basal cells, and peripherally, some tumor cells spread along the adjacent alveolar walls, in a lepidic fashion, and floating in pool of mucin. Tumor cells had bland nuclei, and no mitotic activity was observed. This had been initially misdiagnosed as mucinous adenocarcinoma in frozen section. We reviewed previous articles as well as permanent and frozen slides. In conclusion, in order to reduce the possibility of false positives, it is important to be aware that CMPT is a rare form of peripheral mucin-producing tumor with characteristic histologic findings
17β-Estradiol strongly inhibits azoxymethane/dextran sulfate sodium-induced colorectal cancer development in Nrf2 knockout male mice
© 2020 The Author(s)Nuclear factor erythroid 2-related factor 2 (Nrf2) has dual effects on inflammation and cancer progression depending on the microenvironment. Estrogens have a protective effect on colorectal cancer (CRC) development. The aim of this study was to investigate CRC development in Nrf2 knockout (KO) mice. Azoxymethane (AOM) and dextran sulfate sodium (DSS)-treated wild-type (WT) and Nrf2 KO male mice were sacrificed at weeks 2 and 16 after AOM injection with/without 17β-estradiol (E2) treatment during week 1. Disease activity index and colon tissue damage at week 2 showed strong attenuation following E2 administration in WT mice but to a lesser extent in Nrf2 KO male mice. At week 16, E2 significantly diminished AOM/DSS-induced adenoma/cancer incidence at distal colon in the Nrf2 KO group, but not in the WT. Furthermore, mRNA or protein levels of NF-κB-related mediators (i.e., iNOS, TNF-α, and IL-1β) and Nrf2-related antioxidants (i.e., NQO1 and HO-1) were significantly lower in the Nrf2 KO group regardless of E2 treatment compared to the WT. The expression of estrogen receptor beta (ERβ) was higher in the Nrf2 KO group than in the WT. In conclusion, estrogen further inhibits CRC by upregulating ERβ-related alternate pathways in the absence of Nrf2.
Mesenchymal Stem Cell-Extracellular Vesicle Therapy for Stroke: Scalable Production and Imaging Biomarker Studies
A major clinical hurdle to translate MSC-derived extracellular vesicles (EVs) is the lack of a method to scale-up the production of EVs with customized therapeutic properties. In this study, we tested whether EV production by a scalable 3D-bioprocessing method is feasible and improves neuroplasticity in animal models of stroke using MRI study. MSCs were cultured in a 3D-spheroid using a micro-patterned well. The EVs were isolated with filter and tangential flow filtration and characterized using electron microscopy, nanoparticle tracking analysis, and small RNA sequencing. Compared to conventional 2D culture, the production-reproduction of EVs (the number/size of particles and EV purity) obtained from 3D platform were more consistent among different lots from the same donor and among different donors. Several microRNAs with molecular functions associated with neurogenesis were upregulated in EVs obtained from 3D platform. EVs induced both neurogenesis and neuritogenesis via microRNAs (especially, miR-27a-3p and miR-132-3p)-mediated actions. EV therapy improved functional recovery on behavioral tests and reduced infarct volume on MRI in stroke models. The dose of MSC-EVs of 1/30 cell dose had similar therapeutic effects. In addition, the EV group had better anatomical and functional connectivity on diffusion tensor imaging and resting-state functional MRI in a mouse stroke model. This study shows that clinical-scale MSC-EV therapeutics are feasible, cost-effective, and improve functional recovery following experimental stroke, with a likely contribution from enhanced neurogenesis and neuroplasticity
Thyroid Isthmus Length and Iodine Turnover as Predictors of Successful Radioactive Iodine Therapy in Patients with Graves’ Disease
Radioactive iodine (RAI) therapy is an effective treatment option for Graves’ disease. However, predicting treatment failures after RAI therapy remains controversial. The objective of this study was to investigate the factors associated with the success rate of RAI therapy for treatment of Graves’ hyperthyroidism. Thyroid functional outcome, pre-RAI ultrasonographic features, and clinical parameters were evaluated retrospectively in 98 patients followed up for at least 12 months after RAI (mean RAI dose was 11.7 ± 1.8 mCi). Hypothyroidism was achieved in 59 patients (60.2%), and euthyroidism in 16 patients (16.3%), while 23 patients (23.5%) remained hyperthyroid. Age, sex, body mass index, pre-RAI thyroid function, or thyroid-stimulating immunoglobulin levels were not associated with treatment outcome. Length of thyroid isthmus (p=0.028) and 2- to 24-hour iodine uptake ratios (p=0.002) were significantly associated with treatment failure, which was defined as a persistent hyperthyroid status after RAI therapy. Patients with a longer isthmus had a higher risk of remaining hyperthyroid, with a threshold for isthmus length of 5.2 mm, with a sensitivity of 69.6% and specificity of 70.3% for treatment success. Measuring the length of the thyroid isthmus can be a simple and useful way to predict RAI treatment outcome
Depressed Neuronal Growth Associated Protein (GAP)-43 Expression in the Small Intestines of Mice Experimentally Infected with Neodiplostomum seoulense
Neodiplostomum seoulense (Digenea: Neodiplostomidae) is an intestinal trematode that can cause severe mucosal pathology in the small intestines of mice and even mortality of the infected mice within 28 days after infection. We observed neuronal growth associated protein-43 (GAP-43) expression in the myenteric plexus of the small intestinal wall of N. seoulense-infected mice until day 35 post-infection (PI). BALB/c mice were infected with 200 or 500 N. seoulense metacercariae isolated from naturally infected snakes and were killed every 7 days for immunohistochemical demonstration of GAP-43 in the small intestines. N. seoulense-infected mice showed remarkable dilatation of intestinal loops compared with control mice through days 7-28 PI. Conversely, GAP-43 expression in the mucosal myenteric plexus was markedly (P<0.05) reduced in the small intestines of N. seoulense-infected mice during days 7-28 PI and was slightly normalized at day 35 PI. From this study, it is evident that neuronal damage occurs in the intestinal mucosa of N. seoulense-infected mice. However, the correlation between intestinal pathology, including the loop dilatation, and depressed GAP-43 expression remains to be elucidated
The lipoxygenase gene family: a genomic fossil of shared polyploidy between Glycine max and Medicago truncatula
<p>Abstract</p> <p>Background</p> <p>Soybean lipoxygenases (<it>Lxs</it>) play important roles in plant resistance and in conferring the distinct bean flavor. <it>Lxs </it>comprise a multi-gene family that includes <it>GmLx1</it>, <it>GmLx2 </it>and <it>GmLx3</it>, and many of these genes have been characterized. We were interested in investigating the relationship between the soybean lipoxygenase isozymes from an evolutionary perspective, since soybean has undergone two rounds of polyploidy. Here we report the tetrad genome structure of soybean <it>Lx </it>regions produced by ancient and recent polyploidy. Also, comparative genomics with <it>Medicago truncatula </it>was performed to estimate <it>Lxs </it>in the common ancestor of soybean and <it>Medicago</it>.</p> <p>Results</p> <p>Two <it>Lx </it>regions in <it>Medicago truncatula </it>showing synteny with soybean were analyzed. Differential evolutionary rates between soybean and <it>Medicago </it>were observed and the median Ks values of Mt-Mt, Gm-Mt, and Gm-Gm paralogs were determined to be 0.75, 0.62, and 0.46, respectively. Thus the comparison of Gm-Mt paralogs (Ks = 0.62) and Gm-Mt orthologs (Ks = 0.45) supports the ancient duplication of <it>Lx </it>regions in the common ancestor prior to the <it>Medicago</it>-<it>Glycine </it>split. After speciation, no <it>Lx </it>regions generated by another polyploidy were identified in <it>Medicago</it>. Instead tandem duplication of <it>Lx </it>genes was observed. On the other hand, a lineage-specific duplication occurred in soybean resulting in two pairs of <it>Lx </it>regions. Each pair of soybean regions was co-orthologous to one <it>Lx </it>region in <it>Medicago</it>. A total of 34 <it>Lx </it>genes (15 <it>MtLxs </it>and 19 <it>GmLxs) </it>were divided into two groups by phylogenetic analysis. Our study shows that the <it>Lx </it>gene family evolved from two distinct <it>Lx </it>genes in the most recent common ancestor.</p> <p>Conclusion</p> <p>This study analyzed two pairs of <it>Lx </it>regions generated by two rounds of polyploidy in soybean. Each pair of soybean homeologous regions is co-orthologous to one region of <it>Medicago</it>, demonstrating the quartet structure of the soybean genome. Differential evolutionary rates between soybean and <it>Medicago </it>were observed; thus optimized rates of Ks per year should be applied for accurate estimation of coalescence times to each case of comparison: soybean-soybean, soybean-<it>Medicago</it>, or <it>Medicago</it>-<it>Medicago</it>. In conclusion, the soybean <it>Lx </it>gene family expanded by ancient polyploidy prior to taxon divergence, followed by a soybean- specific duplication and tandem duplications, respectively.</p
TCT-341 Thrombus And Plaque Erosion In Patients With Vasospastic Angina Using Optical Coherence Tomography
The ancient phosphatidylinositol 3-kinase signaling system is a master regulator of energy and carbon metabolism in algae
Algae undergo a complete metabolic transformation under stress by arresting cell growth, inducing autophagy and hyperaccumulating biofuel precursors such as triacylglycerols and starch. However, the regulatory mechanisms behind this stress-induced transformation are still unclear. Here, we use biochemical, mutational, and “omics” approaches to demonstrate that PI3K signaling mediates the homeostasis of energy molecules and influences carbon metabolism in algae. In Chlamydomonas reinhardtii, the inhibition and knockdown (KD) of algal class III PI3K led to significantly decreased cell growth, altered cell morphology, and higher lipid and starch contents. Lipid profiling of wild-type and PI3K KD lines showed significantly reduced membrane lipid breakdown under nitrogen starvation (-N) in the KD. RNA-seq and network analyses showed that under -N conditions, the KD line carried out lipogenesis rather than lipid hydrolysis by initiating de novo fatty acid biosynthesis, which was supported by tricarboxylic acid cycle down-regulation and via acetyl-CoA synthesis from glycolysis. Remarkably, autophagic responses did not have primacy over inositide signaling in algae, unlike in mammals and vascular plants. The mutant displayed a fundamental shift in intracellular energy flux, analogous to that in tumor cells. The high free fatty acid levels and reduced mitochondrial ATP generation led to decreased cell viability. These results indicate that the PI3K signal transduction pathway is the metabolic gatekeeper restraining biofuel yields, thus maintaining fitness and viability under stress in algae. This study demonstrates the existence of homeostasis between starch and lipid synthesis controlled by lipid signaling in algae and expands our understanding of such processes, with biotechnological and evolutionary implications.Ministry of Science, ICT and Future Planning 2015M3A6A2065697Ministry of Oceans and Fisheries 2015018
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