Late gadolinium uptake demonstrated with magnetic resonance in patients where automated PERFIT analysis of myocardial SPECT suggests irreversible perfusion defect

<p>Abstract</p> <p>Background</p> <p>Myocardial perfusion single photon emission computed tomography (MPS) is frequently used as the reference method for the determination of myocardial infarct size. PERFIT^®is a software utilizing a three-dimensional gender specific, averaged heart model for the automatic evaluation of myocardial perfusion. The purpose of this study was to compare the perfusion defect size on MPS, assessed with PERFIT, with the hyperenhanced volume assessed by late gadolinium enhancement magnetic resonance imaging (LGE) and to relate their effect on the wall motion score index (WMSI) assessed with cine magnetic resonance imaging (cine-MRI) and echocardiography (echo).</p> <p>Methods</p> <p>LGE was performed in 40 patients where clinical MPS showed an irreversible uptake reduction suggesting a myocardial scar. Infarct volume, extent and major coronary supply were compared between MPS and LGE as well as the relationship between infarct size from both methods and WMSI.</p> <p>Results</p> <p>MPS showed a slightly larger infarct volume than LGE (MPS 29.6 ± 23.2 ml, LGE 22.1 ± 16.9 ml, p = 0.01), while no significant difference was found in infarct extent (MPS 11.7 ± 9.4%, LGE 13.0 ± 9.6%). The correlation coefficients between methods in respect to infarct size and infarct extent were 0.71 and 0.63 respectively. WMSI determined with cine-MRI correlated moderately with infarct volume and infarct extent (cine-MRI vs MPS volume r = 0.71, extent r = 0.71, cine-MRI vs LGE volume r = 0.62, extent r = 0.60). Similar results were achieved when wall motion was determined with echo. Both MPS and LGE showed the same major coronary supply to the infarct area in a majority of patients, Kappa = 0.84.</p> <p>Conclusion</p> <p>MPS and LGE agree moderately in the determination of infarct size in both absolute and relative terms, although infarct volume is slightly larger with MPS. The correlation between WMSI and infarct size is moderate.</p

Потребительский экстремизм как правовое явление

Материалы XIII Междунар. науч. конф. студентов, магистрантов, аспирантов и молодых ученых, Гомель, 21–22 мая 2020 г

What makes teachers stay? A cross-sectional exploration of the individual and contextual factors associated with teacher retention in Sweden

This cross-sectional study aimed to identify individual and contextual factors associated with Swedish teachers' intention to remain in the profession. A sample of 5903 elementary-year teachers completed a questionnaire between 2004 and 2011 assessing their health and perception of individual and contextual factors at work. The findings showed that teachers' intention to remain in the profession is mainly explained by individual factors, predominantly by teachers’ perceived health state, work motivation and collegial support. The main implication is the importance of teachers' perceived health state for their intention to remain, underscoring the importance of a health promoting work environment in schools.

Enculturating a Protective Professional Community : Processes of Teacher Retention in a Swedish Hard-to-Staff School

This study presented a positive deviant case: a Swedish hard-to-staff school which has had a low rate of teacher turnover over time. In line with the purpose of studying positive deviance in organisations, our exploratory inquiry was geared towards understanding how and why ‘at-risk’ teachers, i.e., teachers who teach in subjects which are known to have high levels of staffing difficulties in Sweden, stayed at this particular school. Using a modified grounded theory approach, our results suggested that teachers remained at the school due to being embedded in a protective professional community that was enculturated by different expressions of collegiality. Finally, these findings are discussed in relation to the theoretical concepts of teachers’ job embeddedness and social capital.

Image quality and myocardial scar size determined with magnetic resonance imaging in patients with permanent atrial fibrillation : a comparison of two imaging protocols

BACKGROUND: Magnetic resonance imaging (MRI) of the heart generally requires breath holding and a regular rhythm. Single shot 2D steady-state free precession (SS_SSFP) is a fast sequence insensitive to arrhythmia as well as breath holding. Our purpose was to determine image quality, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios and infarct size with a fast single shot and a standard segmented MRI sequence in patients with permanent atrial fibrillation and chronic myocardial infarction. METHODS: Twenty patients with chronic myocardial infarction and ongoing atrial fibrillation were examined with inversion recovery SS_SSFP and segmented inversion recovery 2D fast gradient echo (IR_FGRE). Image quality was assessed in four categories: delineation of infarcted and non-infarcted myocardium, occurrence of artefacts and overall image quality. SNR and CNR were calculated. Myocardial volume (ml) and infarct size, expressed as volume (ml) and extent (%), were calculated, and the methodological error was assessed. RESULTS: SS_SSFP had significantly better quality scores in all categories (P = 0.037, P = 0.014, P = 0.021, P = 0.03). SNR(infarct) and SNR(blood) were significantly better for IR_FGRE than for SS_SSFP (P = 0.048, P = 0.018). No significant difference was found in SNR(myocardium) and CNR. The myocardial volume was significantly larger with SS_SSFP (170.7 versus 159.2 ml, P&lt;0.001), but no significant difference was found in infarct volume and infarct extent. CONCLUSION: SS_SSFP displayed significantly better image quality than IR_FGRE. The infarct size and the error in its determination were equal for both sequences, and the examination time was shorter with SS_SSFP.Funding Agency:Linköping Heart Centre</p

25-hydroxyvitamin D3 1alpha-hydroxylase expression in breast cancer and use of non-hydroxylated vitamin D analogue

INTRODUCTION: The cytochrome P450 mitochondrial enzyme 25-hydroxyvitamin D3 1alpha-hydroxylase (1alpha-hydroxylase) of renal tubule cells hydroxylates the major circulating form of vitamin D (25(OH)D3) to the active systemic hormone 1,25(OH)2D3. Local production of 1,25(OH)2D3 appears to occur also at other sites where 1alpha-hydroxylase is expressed for autocrine/paracrine regulation. To reduce risks of hypercalcemia during treatment with vitamin D, we have previously suggested use of non-1alpha-hydroxylated vitamin D analogues to target tissues where 1alpha-hydroxylase is expressed, including the parathyroid glands in secondary hyperparathyroidism. The present study was undertaken to examine expression of 1alpha-hydroxylase in breast cancer and to investigate whether a non-1alpha-hydroxylated vitamin D analogue displayed biological function. In addition, expression of the 25-hydroxyvitamin D3 24-hydroxylase (24-hydroxylase) and the vitamin D receptor (VDR) was investigated. METHODS: The expression of 1alpha-hydroxylase, 24-hydroxylase and VDR was investigated in breast cancer specimens (n = 19) and normal breast tissues (n = 10) by immunohistochemistry and/or RT-PCR. Consecutive cryosections of 6 mum essentially free of immune cells were used in the analyses. The effect of vitamin D analogues on transcriptional activation was analyzed in transiently transfected MCF-7 breast cancer cells. RESULTS: 1alpha-hydroxylase protein was demonstrated in 79% and 100% of breast cancer specimens and normal breast, respectively. The overall relative mRNA levels of 1alpha-hydroxylase and 24-hydroxylase in normal breast compared to breast tumors were: 1alpha-hydroxylase, 1 +/- 0.07 versus 0.7 +/- 0.05, respectively (p &lt; 0.001); 24-hydroxylase, 1 +/- 0.08 verus 2.1 +/- 0.2, respectively (p &lt; 0.001). The VDR was expressed in 95% of the tumors as expected, with mRNA levels of 1 +/- 0.09 and 1.4 +/- 0.12 (p &lt; 0.05) in breast cancer and normal breast, respectively. The ketoconazole-sensitive transcription activation potential of the non-1alpha-hydroxylated vitamin D analogue prodrug of EB1089 (EB1285) was demonstrated in MCF-7 cells, which express 1alpha-hydroxylase. The activity of EB1285 was about 20% of 1,25(OH)2D3. CONCLUSION: These results demonstrate nearly normal expression levels of 1alpha-hydroxylase, 24-hydroxylase and VDR in the majority of investigated breast cancer specimens. A non-1alpha-hydroxylated vitamin D analogue displayed activity in breast cancer cells. Such analogues may present future therapeutic options for proliferative disorders where 1alpha-hydroxylase is expressed

Neomorphic effects of recurrent somatic mutations in Yin Yang 1

Insulinomas are pancreatic islet tumors that inappropriately secrete insulin, producing hypoglycemia. Exome and targeted sequencing revealed that 14 of 43 insulinomas harbored the identical somatic mutation in the DNA-binding zinc finger of the transcription factor Yin Yang 1 (YY1). Chromatin immunoprecipitation sequencing (ChIP-Seq) showed that this T372R substitution changes the DNA motif bound by YY1. Global analysis of gene expression demonstrated distinct clustering of tumors with and without YY1(T372R) mutations. Genes showing large increases in expression in YY1(T372R) tumors included ADCY1 (an adenylyl cyclase) and CACNA2D2 (a Ca(2+) channel); both are expressed at very low levels in normal β-cells and show mutation-specific YY1 binding sites. Both gene products are involved in key pathways regulating insulin secretion. Expression of these genes in rat INS-1 cells demonstrated markedly increased insulin secretion. These findings indicate that YY1(T372R) mutations are neomorphic, resulting in constitutive activation of cAMP and Ca(2+) signaling pathways involved in insulin secretion