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BACKGROUND: IGTS is a rare phenomenon of paradoxical germ cell tumor (GCT) growth during or following treatment despite normalization of tumor markers. We sought to evaluate the frequency, clinical characteristics and outcome of IGTS in patients in 21 North-American and Australian institutions. METHODS: Patients with IGTS diagnosed from 2000-2017 were retrospectively evaluated. RESULTS: Out of 739 GCT diagnoses, IGTS was identified in 33 patients (4.5%). IGTS occurred in 9/191 (4.7%) mixed-malignant GCTs, 4/22 (18.2%) immature teratomas (ITs), 3/472 (0.6%) germinomas/germinomas with mature teratoma, and in 17 secreting non-biopsied tumours. Median age at GCT diagnosis was 10.9 years (range 1.8-19.4). Male gender (84%) and pineal location (88%) predominated. Of 27 patients with elevated markers, median serum AFP and Beta-HCG were 70 ng/mL (range 9.2-932) and 44 IU/L (range 4.2-493), respectively. IGTS occurred at a median time of 2 months (range 0.5-32) from diagnosis, during chemotherapy in 85%, radiation in 3%, and after treatment completion in 12%. Surgical resection was attempted in all, leading to gross total resection in 76%. Most patients (79%) resumed GCT chemotherapy/radiation after surgery. At a median follow-up of 5.3 years (range 0.3-12), all but 2 patients are alive (1 succumbed to progressive disease, 1 to malignant transformation of GCT). CONCLUSION: IGTS occurred in less than 5% of patients with GCT and most commonly after initiation of chemotherapy. IGTS was more common in patients with IT-only on biopsy than with mixed-malignant GCT. Surgical resection is a principal treatment modality. Survival outcomes for patients who developed IGTS are favourable.
Because polarization encodes geometrical information about unresolved scattering regions, it provides a unique tool for analyzing the 3-D structures of supernovae (SNe) and their surroundings. SNe of all types exhibit time-dependent spectropolarimetric signatures produced primarily by electron scattering. These signatures reveal physical phenomena such as complex velocity structures, changing illumination patterns, and asymmetric morphologies within the ejecta and surrounding material. Interpreting changes in polarization over time yields unprecedentedly detailed information about supernovae, their progenitors, and their evolution.
Begun in 2012, the SNSPOL Project continues to amass the largest database of time-dependent spectropolarimetric data on SNe. I present an overview of the project and its recent results. In the future, combining such data with interpretive radiative transfer models will further constrain explosion mechanisms and processes that shape SN ejecta, uncover new relationships among SN types, and probe the properties of progenitor winds and circumstellar material.
Fontan survivors have depressed cardiac index that worsens over time. Serum biomarker measurement is minimally invasive, rapid, widely available, and may be useful for serial monitoring. The purpose of this study was to identify biomarkers that correlate with lower cardiac index in Fontan patients.
Methods and results
This study was a multi-centre case series assessing the correlations between biomarkers and cardiac magnetic resonance-derived cardiac index in Fontan patients ⩾6 years of age with biochemical and haematopoietic biomarkers obtained ±12 months from cardiac magnetic resonance. Medical history and biomarker values were obtained by chart review. Spearman’s Rank correlation assessed associations between biomarker z-scores and cardiac index. Biomarkers with significant correlations had receiver operating characteristic curves and area under the curve estimated. In total, 97 cardiac magnetic resonances in 87 patients met inclusion criteria: median age at cardiac magnetic resonance was 15 (6–33) years. Significant correlations were found between cardiac index and total alkaline phosphatase (−0.26, p=0.04), estimated creatinine clearance (0.26, p=0.02), and mean corpuscular volume (−0.32, p<0.01). Area under the curve for the three individual biomarkers was 0.63–0.69. Area under the curve for the three-biomarker panel was 0.75. Comparison of cardiac index above and below the receiver operating characteristic curve-identified cut-off points revealed significant differences for each biomarker (p<0.01) and for the composite panel [median cardiac index for higher-risk group=2.17 L/minute/m2 versus lower-risk group=2.96 L/minute/m2, (p<0.01)].
Higher total alkaline phosphatase and mean corpuscular volume as well as lower estimated creatinine clearance identify Fontan patients with lower cardiac index. Using biomarkers to monitor haemodynamics and organ-specific effects warrants prospective investigation.
We present the observed “continuum” levels of polarization as a function of time for four well-observed Type II-Plateau supernovae (SNe II-P; Fig. 1), the class of SNe decisively determined to arise from red supergiant stars (Smartt 2009). All four objects show temporally increasing degrees of polarization through the end of the photospheric phase, with some exhibiting early-time polarization that challenge existing models (e.g., Dessart and Hillier 2011) to reproduce. A fundamental ejecta asymmetry is present in this photometrically diverse sample of type II SNe, and it probably takes different forms (e.g., 56Ni blobs/fingers, large scale deformation). We acknowledge support from NSF grants AST-1009571 and AST-1210311.
Voters and political candidates increasingly use social networking sites (SNSs) such as Facebook. This study uses data from an online posttest-only experiment (N = 183) in analyzing how exposure to supportive or challenging user comments on a fictional candidate's Facebook page influenced participants’ perceptions of and willingness to vote for the candidate, as well as whether candidate replies to each type of user comments affected these outcomes. Participants who viewed a page with supportive comments and “likes” reported more favorable perceptions of and greater support for the candidate, relative to participants who viewed a page with challenging comments. Thus, the appearance of interactivity between a candidate and other users on the candidate's Facebook page can shape the responses of those viewing the page. However, exposure to candidate replies to either supportive or challenging comments did not lead to significantly more favorable perceptions or a greater likelihood of voting for the candidate.
‘What makes modern constitutions work?’ The one-word answer to that question, if there is one, is ‘accountability’. A society which has the necessary political will to exact accountability from those in charge is one in which constitutionalism has the chance to flourish. Accountability may thus be defined as the obligation of those with power or authority to explain their performance or justify their decisions. This chapter examines aspects of the notion of democratic constitutionalism that have been incorporated as founding provisions of the new dispensation in South Africa.
Democracy in its classical Greek form meant exactly the same as that claimed in the liberation struggles of Africa so many thousands of years later: ‘Power to the people’ or, in local parlance, ‘Amandla awethu!’
The problem with the liberation movements of Africa, including South Africa, is that what starts out as the people's struggle for freedom transmogrifies along the way into the politicians’ or ruling elites’ struggles for power. This is where constitutional theory and practical politics part company. The yearnings for freedom from the yoke of colonialism, racism and ethnic dominance become subjugated to the power plays of factions within the ruling elite, and the ordinary people often find themselves worse off (as in Zimbabwe now) or not much better off (as seen elsewhere in postcolonial Africa) than they were before receiving the blessing of liberation. Nevertheless, ordinary voters feel a national debt of gratitude towards liberation movements, and these movements continue to draw electoral support (both real and contrived) in the most perplexing of circumstances and often well after their sell-by date. Robert Mugabe only – and only just – lost a general election in March 2008, twenty-eight years after ‘liberating’ his country. He is not exceptional. Many of the so-called ‘big men’ of Africa continue to rule their grateful but oppressed followers long after the stated purpose of the liberation struggle has been achieved. The promotion of human dignity, the achievement of equality and the advancement of the various freedoms for which ordinary Africans have struggled are the main casualties of this unfortunate process. In South Africa, the lack of governmental responsiveness to the needs of ordinary people has sparked widespread service delivery protests (or activities dressed up as service delivery protests which are in fact the upshot of faction fighting within the governing Tripartite Alliance).