62 research outputs found
Exploring international differences in ovarian cancer care: a survey report on global patterns of care, current practices, and barriers
OBJECTIVE: Although global disparities in survival rates for patients with ovarian cancer have been described, variation in care has not been assessed globally. This study aimed to evaluate global ovarian cancer care and barriers to care. METHODS: A survey was developed by international ovarian cancer specialists and was distributed through networks and organizational partners of the International Gynecologic Cancer Society, the Society of Gynecologic Oncology, and the European Society of Gynecological Oncology. Respondents received questions about care organization. Outcomes were stratified by World Bank Income category and analyzed using descriptive statistics and logistic regressions. RESULTS: A total of 1059 responses were received from 115 countries. Respondents were gynecological cancer surgeons (83%, n=887), obstetricians/gynecologists (8%, n=80), and other specialists (9%, n=92). Income category breakdown was as follows: high-income countries (46%), upper-middle-income countries (29%), and lower-middle/low-income countries (25%). Variation in care organization was observed across income categories. Respondents from lower-middle/low-income countries reported significantly less frequently that extensive resections were routinely performed during cytoreductive surgery. Furthermore, these countries had significantly fewer regional networks, cancer registries, quality registries, and patient advocacy groups. However, there is also scope for improvement in these components in upper-middle/high-income countries. The main barriers to optimal care for the entire group were patient co-morbidities, advanced presentation, and social factors (travel distance, support systems). High-income respondents stated that the main barriers were lack of surgical time/staff and patient preferences. Middle/low-income respondents additionally experienced treatment costs and lack of access to radiology/pathology/genetic services as main barriers. Lack of access to systemic agents was reported by one-third of lower-middle/low-income respondents. CONCLUSIONS: The current survey report highlights global disparities in the organization of ovarian cancer care. The main barriers to optimal care are experienced across all income categories, while additional barriers are specific to income levels. Taking action is crucial to improve global care and strive towards diminishing survival disparities and closing the care gap
Fundamental optical processes in armchair carbon nanotubes
Single-wall carbon nanotubes provide ideal model one-dimensional (1-D) condensed matter systems in
which to address fundamental questions in many-body physics, while, at the same time, they are
leading candidates for building blocks in nanoscale optoelectronic circuits. Much attention has been
recently paid to their optical properties, arising from 1-D excitons and phonons, which have been
revealed via photoluminescence, Raman scattering, and ultrafast optical spectroscopy of semiconducting
carbon nanotubes. On the other hand, dynamical properties of metallic nanotubes have been poorly
explored, although they are expected to provide a novel setting for the study of electronďľ–hole pairs in
the presence of degenerate 1-D electrons. In particular, (n,n)-chirality, or armchair, metallic nanotubes
are truly gapless with massless carriers, ideally suited for dynamical studies of Tomonagaďľ–Luttinger
liquids. Unfortunately, progress towards such studies has been slowed by the inherent problem of
nanotube synthesis whereby both semiconducting and metallic nanotubes are produced. Here, we use
post-synthesis separation methods based on density gradient ultracentrifugation and DNA-based ion-exchange chromatography to produce aqueous suspensions strongly enriched in armchair nanotubes.
Through resonant Raman spectroscopy of the radial breathing mode phonons, we provide macroscopic
and unambiguous evidence that density gradient ultracentrifugation can enrich ensemble samples in
armchair nanotubes. Furthermore, using conventional, optical absorption spectroscopy in the nearinfrared
and visible range, we show that interband absorption in armchair nanotubes is strongly
excitonic. Lastly, by examining the G-band mode in Raman spectra, we determine that observation of
the broad, lower frequency (G!) feature is a result of resonance with non-armchair “metallic”
nanotubes. These !ndings regarding the fundamental optical absorption and scattering processes in
metallic carbon nanotubes lay the foundation for further spectroscopic studies to probe many-body
physical phenomena in one dimension
Plant 45S rDNA Clusters Are Fragile Sites and Their Instability Is Associated with Epigenetic Alterations
Our previous study demonstrated that 45S ribosomal DNA (45S rDNA) clusters were chromosome fragile sites expressed spontaneously in Lolium. In this study, fragile phenotypes of 45S rDNA were observed under aphidicolin (APH) incubation in several plant species. Further actinomycin D (ActD) treatment showed that transcriptional stress might interfere with chromatin packaging, resulting in 45S rDNA fragile expression. These data identified 45S rDNA sites as replication-dependent as well as transcription-dependent fragile sites in plants. In the presence of ActD, a dramatic switch to an open chromatin conformation and accumulated incomplete 5′ end of the external transcribed spacer (5′ETS) transcripts were observed, accompanied by decreased DNA methylation, decreased levels of histone H3, and increased histone acetylation and levels of H3K4me2, suggesting that these epigenetic alterations are associated with failure of 45S rDNA condensation. Furthermore, the finding that γ-H2AX was accumulated at 45S rDNA sites following ActD treatment suggested that the DNA damage signaling pathway was associated with the appearance of 45S rDNA fragile phenotypes. Our data provide a link between 45S rDNA transcription and chromatin-packaging defects and open the door for further identifying the molecular mechanism involved
Designed Metal-ATCUN Derivatives: Redox- and Non-redox-Based Applications Relevant for Chemistry, Biology, and Medicine
UID/QUI/50006/2019The designed "ATCUN'' motif (amino-terminal copper and nickel binding site) is a replica of naturally occurring ATCUN site found in many proteins/peptides, and an attractive platform for multiple applications, which include nucleases, proteases, spectroscopic probes, imaging, and small molecule activation. ATCUN motifs are engineered at periphery by conjugation to recombinant proteins, peptides, fluorophores, or recognition domains through chemically or genetically, fulfilling the needs of various biological relevance and a wide range of practical usages. This chemistry has witnessed significant growth over the last few decades and several interesting ATCUN derivatives have been described. The redox role of the ATCUN moieties is also an important aspect to be considered. The redox potential of designed M-ATCUN derivatives is modulated by judicious choice of amino acid (including stereochemistry, charge, and position) that ultimately leads to the catalytic efficiency. In this context, a wide range of M-ATCUN derivatives have been designed purposefully for various redox- and non-redox-based applications, including spectroscopic probes, target-based catalytic metallodrugs, inhibition of amyloid-beta toxicity, and telomere shortening, enzyme inactivation, biomolecules stitching or modification, next-generation antibiotic, and small molecule activation.publishersversionpublishe
Finding alternatives to swidden agriculture: does agroforestry improve livelihood options and reduce pressure on existing forest?
Predicting excitonic gaps of semiconducting single-walled carbon nanotubes from a field theoretic analysis
Feasibility of guayule commodity chain in the Mediterranean region
DiaporamaInternational audienc
Participation: a pillar of sustainable forest management in the Mediterranean
Partie III - Mediterranean forest-based solutions. Chapter 12International audienc
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