104 research outputs found
Lack of a Y-Chromosomal Complement in the Majority of Gestational Trophoblastic Neoplasms
Gestational trophoblastic neoplasms (GTNs) are a rare group of neoplastic diseases composed of choriocarcinomas, placental site trophoblastic tumors (PSTTs) and epithelioid trophoblastic tumors (ETTs). Since these tumors are derivatives of fetal trophoblastic tissue, approximately 50% of GTN cases are expected to originate from a male conceptus and carry a Y-chromosomal complement according to a balanced sex ratio. To investigate this hypothesis, we carried out a comprehensive analysis by genotyping a relatively large sample size of 51 GTN cases using three independent sex chromosome genetic markers; Amelogenin, Protein Kinase and Zinc Finger have X and
Y homologues that are distinguishable by their PCR product size. We found that all cases contained the X-chromosomal complement while only five (10%) of 51 tumors harbored the Y-chromosomal complement. Specifically, Y-chromosomal signals were detected in
one (5%) of 19 choriocarcinomas, one (7%) of 15 PSTTs and three (18%) of 17 ETTs. The histopathological features of those with a Y-chromosome were similar to those without. Our results demonstrate the presence of a Y-chromosomal complement in
GTNs, albeit a low 10% of cases. This shortfall of Y-chromosomal complements in GTNs may reinforce the notion that the majority of GTNs are derived from previous molar gestations
Observation of the Stimulated Quantum Cherenkov Effect
As charged particles surpass the speed of light in an optical medium they
produce radiation - analogously to the way jet planes surpass the speed of
sound and produce a sonic boom. This radiation emission, known as the Cherenkov
effect, is among the most fundamental processes in electrodynamics. As such, it
is used in numerous applications of particle detectors, particle accelerators,
light sources, and medical imaging. Surprisingly, all Cherenkov-based
applications and experiments thus far were fully described by classical
electrodynamics even though theoretical work predicts new Cherenkov phenomena
coming from quantum electrodynamics. The quantum description could provide new
possibilities for the design of highly controllable light sources and more
efficient accelerators and detectors. Here, we provide a direct evidence of the
quantum nature of the Cherenkov effect and reveal its intrinsic quantum
features. By satisfying the Cherenkov condition for relativistic electron
wavefunctions and maintaining it over hundreds of microns, each electron
simultaneously accelerates and decelerates by absorbing and emitting hundreds
of photons in a coherent manner. We observe this strong interaction in an
ultrafast transmission electron microscope, achieving for the first time a
phase-matching between a relativistic electron wavefunction and a propagating
light wave. Consequently, the quantum wavefunction of each electron evolves
into a coherent plateau, analogous to a frequency comb in ultrashort laser
pulses, containing hundreds of quantized energy peaks. Our findings prove that
the delocalized wave nature of electrons can become dominant in stimulated
interactions. In addition to prospects for known applications of the Cherenkov
effect, our work provides a platform for utilizing quantum electrodynamics for
applications in electron microscopy and in free-electron pump-probe
spectroscopy.Comment: 15 pages, 4 figure
Spatiotemporal imaging of 2D polariton wave packet dynamics using free electrons
Peer ReviewedPostprint (author's final draft
Greco-2: A randomized, phase 2 study of stereotactic body radiation therapy (SBRT) in combination with rucosopasem (GC4711) in the treatment of locally advanced or borderline resectable nonmetastatic pancreatic cancer
Background: While treatment of pancreatic cancer has advanced, survival rates remain low. Stereotactic body radiotherapy (SBRT; high dose per fraction radiation) may exhibit improved clinical outcomes in locally advanced pancreatic cancer but carries potential gastrointestinal toxicity risks. Rucosopasem (GC4711) is one of a class of investigational selective dismutase mimetics that rapidly and specifically converts superoxide to hydrogen peroxide. Studies have shown that normal cells tolerate hydrogen peroxide fluxes better than cancer cells. As radiation response modifiers, dismutase mimetics have the potential to increase tumor control of SBRT without compromising radiation safety. In a pilot phase 1/2 trial in patients with pancreatic cancer, avasopasem, a dismutase mimetic related to rucosopasem, nearly doubled median overall survival in patients receiving SBRT vs placebo plus SBRT. Improvements versus placebo were also observed in local tumor control, time to metastases, and progression-free survival. Altogether, these data support the hypothesis that rucosopasem may improve survival and the benefit-risk ratio of SBRT by improving efficacy without increasing gastrointestinal toxicity.
Methods: GRECO-2 is a phase 2, multicenter, randomized, double-blind, placebo-controlled study (NCT04698915) to determine the effect of adding rucosopasem to SBRT on overall survival in patients with borderline resectable or locally advanced, unresectable nonmetastatic pancreatic cancer following initial chemotherapy with a FOLFIRINOX-based regimen or a gemcitabine doublet. Approximately 160 patients will be randomized (approximately 35 sites) to receive rucosopasem 100 mg or placebo via IV infusion over 15 minutes, prior to each SBRT fraction (5 x 10 Gy). Patients judged to be resectable will undergo surgical exploration within 8 weeks after SBRT. The primary endpoint is overall survival. Secondary endpoints include progression-free survival, locoregional control, time to metastasis, surgical resection rate, RO resection rate, best overall response, in-field local response, and safety (acute and late toxicities). Exploratory endpoints include PRO-CTCAE and CA19-9 normalization
Nine-valent HPV vaccine efficacy against related diseases and definitive therapy:comparison with historic placebo population
Culture-level dimensions of social axioms and their correlates across 41 cultures
Leung and colleagues have revealed a five-dimensional structure of social axioms across individuals from five cultural groups. The present research was designed to reveal the culture level factor structure of social axioms and its correlates across 41 nations. An ecological factor analysis on the 60 items of the Social Axioms Survey extracted two factors: Dynamic Externality correlates with value measures tapping collectivism, hierarchy, and conservatism and with national indices indicative of lower social development. Societal Cynicism is less strongly and broadly correlated with previous values measures or other national indices and
seems to define a novel cultural syndrome. Its national correlates suggest that it taps the cognitive component of a cultural constellation labeled maleficence, a cultural syndrome associated with a general mistrust of social systems and other people. Discussion focused on the meaning of these national level factors of beliefs and on their relationships with individual level factors of belief derived from the same data set.(undefined
Identification of 12 new susceptibility loci for different histotypes of epithelial ovarian cancer.
To identify common alleles associated with different histotypes of epithelial ovarian cancer (EOC), we pooled data from multiple genome-wide genotyping projects totaling 25,509 EOC cases and 40,941 controls. We identified nine new susceptibility loci for different EOC histotypes: six for serous EOC histotypes (3q28, 4q32.3, 8q21.11, 10q24.33, 18q11.2 and 22q12.1), two for mucinous EOC (3q22.3 and 9q31.1) and one for endometrioid EOC (5q12.3). We then performed meta-analysis on the results for high-grade serous ovarian cancer with the results from analysis of 31,448 BRCA1 and BRCA2 mutation carriers, including 3,887 mutation carriers with EOC. This identified three additional susceptibility loci at 2q13, 8q24.1 and 12q24.31. Integrated analyses of genes and regulatory biofeatures at each locus predicted candidate susceptibility genes, including OBFC1, a new candidate susceptibility gene for low-grade and borderline serous EOC
Targeted deep sequencing of mucinous ovarian tumors reveals multiple overlapping RAS-pathway activating mutations in borderline and cancerous neoplasms
Light-based technologies for management of COVID-19 pandemic crisis.
The global dissemination of the novel coronavirus disease (COVID-19) has accelerated the need for the implementation of effective antimicrobial strategies to target the causative agent SARS-CoV-2. Light-based technologies have a demonstrable broad range of activity over standard chemotherapeutic antimicrobials and conventional disinfectants, negligible emergence of resistance, and the capability to modulate the host immune response. This perspective article identifies the benefits, challenges, and pitfalls of repurposing light-based strategies to combat the emergence of COVID-19 pandemic
Free-electron interactions with van der Waals heterostructures: a source of focused X-ray radiation
The science and technology of X-ray optics have come far, enabling the focusing of X-rays for applications in high-resolution X-ray spectroscopy, imaging, and irradiation. In spite of this, many forms of tailoring waves that had substantial impact on applications in the optical regime have remained out of reach in the X-ray regime. This disparity fundamentally arises from the tendency of refractive indices of all materials to approach unity at high frequencies, making X-ray-optical components such as lenses and mirrors much harder to create and often less efficient. Here, we propose a new concept for X-ray focusing based on inducing a curved wavefront into the X-ray generation process, resulting in the intrinsic focusing of X-ray waves. This concept can be seen as effectively integrating the optics to be part of the emission mechanism, thus bypassing the efficiency limits imposed by X-ray optical components, enabling the creation of nanobeams with nanoscale focal spot sizes and micrometer-scale focal lengths. Specifically, we implement this concept by designing aperiodic vdW heterostructures that shape X-rays when driven by free electrons. The parameters of the focused hotspot, such as lateral size and focal depth, are tunable as a function of an interlayer spacing chirp and electron energy. Looking forward, ongoing advances in the creation of many-layer vdW heterostructures open unprecedented horizons of focusing and arbitrary shaping of X-ray nanobeams.Nanyang Technological UniversityNational Research Foundation (NRF)Published versionThis work was supported by the ERC (Starter Grant No. 851780) and the BSF (Grant No. 2018288). L.J.W. acknowledges the support of the National Research Foundation (Project ID NRF2020-NRF-ISF004-3525) and the Nanyang Assistant Professorship Start-up Grant. F.J.G.d.A. acknowledges support from the Spanish MICINN (PID2020-112625GB-I00 and Severo Ochoa CEX2019-000910-S), ERC (Advanced Grant No. 789104-eNANO), the Catalan CERCA Program, and FundacioÌPrivada Cellex. X.S. is supported in part by a fellowship of the Israel Council for Higher Education and by the Technionâs Helen Diller Quantum Center
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