36 research outputs found
Quantitative trait loci conferring grain mineral nutrient concentrations in durum wheat 3 wild emmer wheat RIL population
Mineral nutrient malnutrition, and particularly
deficiency in zinc and iron, afflicts over 3 billion people
worldwide. Wild emmer wheat, Triticum turgidum ssp.
dicoccoides, genepool harbors a rich allelic repertoire for
mineral nutrients in the grain. The genetic and physiological
basis of grain protein, micronutrients (zinc, iron,
copper and manganese) and macronutrients (calcium,
magnesium, potassium, phosphorus and sulfur) concentration
was studied in tetraploid wheat population of 152
recombinant inbred lines (RILs), derived from a cross
between durum wheat (cv. Langdon) and wild emmer
(accession G18-16). Wide genetic variation was found
among the RILs for all grain minerals, with considerable
transgressive effect. A total of 82 QTLs were mapped for
10 minerals with LOD score range of 3.2–16.7. Most QTLs
were in favor of the wild allele (50 QTLs). Fourteen pairs
of QTLs for the same trait were mapped to seemingly
homoeologous positions, reflecting synteny between the A
and B genomes. Significant positive correlation was found
between grain protein concentration (GPC), Zn, Fe and Cu,
which was supported by significant overlap between the
respective QTLs, suggesting common physiological and/or
genetic factors controlling the concentrations of these
mineral nutrients. Few genomic regions (chromosomes 2A,
5A, 6B and 7A) were found to harbor clusters of QTLs for
GPC and other nutrients. These identified QTLs may
facilitate the use of wild alleles for improving grain
nutritional quality of elite wheat cultivars, especially in
terms of protein, Zn and Fe
Tangential beam IMRT versus tangential beam 3D-CRT of the chest wall in postmastectomy breast cancer patients: A dosimetric comparison
<p>Abstract</p> <p>Background</p> <p>This study evaluates the dose distribution of reversed planned tangential beam intensity modulated radiotherapy (IMRT) compared to standard wedged tangential beam three-dimensionally planned conformal radiotherapy (3D-CRT) of the chest wall in unselected postmastectomy breast cancer patients</p> <p>Methods</p> <p>For 20 unselected subsequent postmastectomy breast cancer patients tangential beam IMRT and tangential beam 3D-CRT plans were generated for the radiotherapy of the chest wall. The prescribed dose was 50 Gy in 25 fractions. Dose-volume histograms were evaluated for the PTV and organs at risk. Parameters of the dose distribution were compared using the Wilcoxon matched pairs test.</p> <p>Results</p> <p>Tangential beam IMRT statistically significantly reduced the ipsilateral mean lung dose by an average of 21% (1129 cGy versus 1437 cGy). In all patients treated on the left side, the heart volume encompassed by the 70% isodose line (V70%; 35 Gy) was reduced by an average of 43% (5.7% versus 10.6%), and the mean heart dose by an average of 20% (704 cGy versus 877 cGy). The PTV showed a significantly better conformity index with IMRT; the homogeneity index was not significantly different.</p> <p>Conclusions</p> <p>Tangential beam IMRT significantly reduced the dose-volume of the ipsilateral lung and heart in unselected postmastectomy breast cancer patients.</p
Is the inflammasome a potential therapeutic target in renal disease?
The inflammasome is a large, multiprotein complex that drives proinflammatory cytokine production in response to infection and tissue injury. Pattern recognition receptors that are either membrane bound or cytoplasmic trigger inflammasome assembly. These receptors sense danger signals including damage-associated molecular patterns and pathogen-associated molecular patterns (DAMPS and PAMPS respectively). The best-characterized inflammasome is the NLRP3 inflammasome. On assembly of the NLRP3 inflammasome, post-translational processing and secretion of pro-inflammatory cytokines IL-1β and IL-18 occurs; in addition, cell death may be mediated via caspase-1. Intrinsic renal cells express components of the inflammasome pathway. This is most prominent in tubular epithelial cells and, to a lesser degree, in glomeruli. Several primary renal diseases and systemic diseases affecting the kidney are associated with NLRP3 inflammasome/IL-1β/IL-18 axis activation. Most of the disorders studied have been acute inflammatory diseases. The disease spectrum includes ureteric obstruction, ischaemia reperfusion injury, glomerulonephritis, sepsis, hypoxia, glycerol-induced renal failure, and crystal nephropathy. In addition to mediating renal disease, the IL-1/ IL-18 axis may also be responsible for development of CKD itself and its related complications, including vascular calcification and sepsis. Experimental models using genetic deletions and/or receptor antagonists/antiserum against the NLRP3 inflammasome pathway have shown decreased severity of disease. As such, the inflammasome is an attractive potential therapeutic target in a variety of renal diseases
Association between the Medical College Admission Test scores and Alpha Omega Alpha Medical Honors Society membership
Jacqueline L Gauer,1 J Brooks Jackson2 1Office of Medical Education, 2Department of Laboratory Medicine and Pathology, Medical School, University of Minnesota, Minneapolis, MN, USA Introduction: Medical schools worldwide are faced with the challenge of selecting from among many qualified applicants. One factor that might help admissions committees identify future exceptional medical students is scores on standardized entrance exams. The purpose of this study was to determine the association between scores on the most commonly used standardized medical school entrance exam in the USA, the Medical College Admission Test (MCAT), and election to the US medical honors society, Alpha Omega Alpha (AOA).Method: MCAT scores and AOA membership data were analyzed for all the students pursuing Doctor of Medicine degrees at the University of Minnesota Medical School and who graduated between 2012–2016 (n=1,309).Results: An independent-samples t-test found a significant difference (t=6.132, p<0.001) in MCAT scores between those who were elected to AOA (n=179) and those who were not (n=1,130). On average, students who were elected to AOA had composite MCAT scores of 1.65 points higher than those who were not. Percentages of students elected to AOA gradually but inconsistently increased with MCAT score. No student who scored <27 on the MCAT was elected to AOA. Among students with MCAT scores at the 99th percentile or above (scores of ≥38), 13 of 48 (27.1%) were elected to AOA. Discussion: Election to AOA during medical school was significantly associated with higher MCAT scores. Admissions committees should carefully consider the role of standardized entrance exam scores, in the context of a holistic review, when selecting for exceptional medical students. Keywords: AOA election, t-test, admissions, medical school, cumulative percentage, medical student honors, selectio
The association between United States Medical Licensing Examination scores and clinical performance in medical students
Jacqueline L Gauer,1 J Brooks Jackson21Medical School, University of Minnesota, Minneapolis, MN, USA; 2Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USAPurpose: United States Medical Licensing Examination (USMLE) Step 1 and Step 2 Clinical Knowledge (CK) scores are frequently used to evaluate applicants to residency programs. Recent literature questions the value of USMLE scores for evaluation of residency applicants, in part due to a lack of evidence supporting a relationship with clinical performance. This study explored the relationship between USMLE scores and medical students’ clinical performance, as measured by the count of honors grades received in core clinical clerkships.Methods: USMLE Step 1 and Step 2 CK scores and number of honors grades per student in seven core clinical clerkships were obtained from 1,511 medical students who graduated in 2013–2017 from two medical schools. The relationships between variables were analyzed using correlation coefficients, independent-samples t-tests, and hierarchical multiple regression.Results: Count of honors grades correlated with both Step 1 (R=0.480, P<0.001) and Step 2 CK (R=0.542, P<0.001). After correcting for gender, institution, and test-taking ability (using MCAT scores as a proxy for test-taking ability) in a hierarchical multiple regression model, Step 1 and Step 2 CK scores together explained 22.2% of the variance in count of honors grades.Conclusion: USMLE Step 1 and Step 2 CK scores moderately correlate with the number of honors grades per student in core clinical clerkships. This relationship is maintained even after correcting for gender, institution, and test-taking ability. These results indicate that USMLE scores have a positive linear association with clinical performance as a medical student.Keywords: United States Medical Licensing Exam, clinical performance, residency application, correlation, hierarchical multiple regressio
Relationships of demographic variables to USMLE physician licensing exam scores: a statistical analysis on five years of medical student data
Jacqueline L Gauer,1 J Brooks Jackson2 1Office of Medical Education, Medical School, University of Minnesota, Minneapolis, MN, USA; 2Department of Laboratory Medicine and Pathology, Medical School, University of Minnesota, Minneapolis, MN, USA Introduction: The purpose of this study was to determine the associations of the demographic variables of gender, state of legal residency, student age, and undergraduate major with scores on the Medical College Admissions Test (MCAT) and the United States Medical Licensing Exam (USMLE) Step 1 and Step 2 Clinical Knowledge.Methods: The researchers collected and analyzed exam scores and demographic student data from participants of five graduating classes of students at the University of Minnesota Medical School (N = 1,067).Results: Significant differences (p < 0.05) were found for traditional-aged (defined as < 25 years old at matriculation) versus nontraditional-aged students on USMLE Step 1 scores (t[1065] = 2.91, p = 0.004) and USMLE Step 2 scores (t[1061] = 4.39, p < 0.001), both in favor of traditional-aged students. Significant differences were found for males versus females on MCAT Composite scores (t[1063] = 6.53, p < 0.001) and USMLE Step 1 scores (t[1065] = 5.14, p < 0.001), both in favor of males. There were no significant differences between science and nonscience majors or between Minnesota legal residents and nonresidents.Conclusion: Traditional age and male gender were associated with higher exam scores, although patterns differed between tests, whereas undergraduate major and state of legal residency were not associated with higher exam scores. Keywords: licensing exams, demographics, gender, age, undergraduate major, state of legal residenc