Abstract
Anatase TiO
2
is among the most studied materials for light-energy conversion applications, but the nature of its fundamental charge excitations is still unknown. Yet it is crucial to ...establish whether light absorption creates uncorrelated electron–hole pairs or bound excitons and, in the latter case, to determine their character. Here, by combining steady-state angle-resolved photoemission spectroscopy and spectroscopic ellipsometry with state-of-the-art ab initio calculations, we demonstrate that the direct optical gap of single crystals is dominated by a strongly bound exciton rising over the continuum of indirect interband transitions. This exciton possesses an intermediate character between the Wannier–Mott and Frenkel regimes and displays a peculiar two-dimensional wavefunction in the three-dimensional lattice. The nature of the higher-energy excitations is also identified. The universal validity of our results is confirmed up to room temperature by observing the same elementary excitations in defect-rich samples (doped single crystals and nanoparticles) via ultrafast two-dimensional deep-ultraviolet spectroscopy.
Abstract Magnetic van der Waals (vdW) materials have opened new frontiers for realizing novel many-body phenomena. Recently NiPS 3 has received intense interest since it hosts an excitonic ...quasiparticle whose properties appear to be intimately linked to the magnetic state of the lattice. Despite extensive studies, the electronic character, mobility, and magnetic interactions of the exciton remain unresolved. Here we address these issues by measuring NiPS 3 with ultra-high energy resolution resonant inelastic x-ray scattering (RIXS). We find that Hund’s exchange interactions are primarily responsible for the energy of formation of the exciton. Measuring the dispersion of the Hund’s exciton reveals that it propagates in a way that is analogous to a double-magnon. We trace this unique behavior to fundamental similarities between the NiPS 3 exciton hopping and spin exchange processes, underlining the unique magnetic characteristics of this novel quasiparticle.
The most common endocrine malignancy is thyroid cancer, and researchers have made a great deal of progress in deciphering its molecular mechanisms in the recent years. Many of molecular changes ...observed in thyroid cancer can be used as biomarkers for diagnosis, prognosis, and therapeutic targets for treatment. MicroRNAs (miRNAs) are important parts in biological and metabolic pathways such as regulation of developmental stages, signal transduction, cell maintenance, and differentiation. Therefore, their dysregulation can expose individuals to malignancies. It has been proved that miRNA expression is dysregulated in different types of tumors, like thyroid cancers, and can be the cause of tumor initiation and progression. In this paper, we have reviewed the available data on miRNA dysregulation in different thyroid tumors including papillary, follicular, anaplastic, and medullary thyroid carcinomas aiming to introduce the last updates in miRNAs-thyroid cancer relation.
Approximately one-third of all non-small-cell lung cancer (NSCLC) are locally-advanced at diagnosis, and 15–17% of these tumors are unresectable at presentation. Definitive chemo-radiotherapy (CRT) ...represents the standard therapeutic approach. However, the literature has shown that only 15% of patients are alive at 5 years and this percentage has remained unchanged despite various attempts of improvement. The recent introduction of immunotherapy has not only strongly changed the clinical scenario but has also drawn attention to a stage of disease apparently forgotten for decades. Stage III NSCLC can represent an interesting setting for the combined use of chemo-radiation and immunotherapy, due to the potential synergistic effect between radiation and immune checkpoint inhibitors. We reviewed the available literature in order to report the state of art of stage III NSCLC, by focusing on trials that evaluate different combinations of CRT and new drugs of PD-1/PD-L1 axis, and anti-CTLA-4. The future goal in the management of unresectable stage III NSCLC will be the optimal patients’ selection combined with the use of individualized immuno/chemotherapies that could potentially improve clinical outcomes.
Transition metal oxides are among the most promising solar materials, whose properties rely on the generation, transport and trapping of charge carriers (electrons and holes). Identifying the ...latter's dynamics at room temperature requires tools that combine elemental and structural sensitivity, with the atomic scale resolution of time (femtoseconds, fs). Here, we use fs Ti K-edge X-ray absorption spectroscopy (XAS) upon 3.49 eV (355 nm) excitation of aqueous colloidal anatase titanium dioxide nanoparticles to probe the trapping dynamics of photogenerated electrons. We find that their localization at Titanium atoms occurs in <300 fs, forming Ti(3+) centres, in or near the unit cell where the electron is created. We conclude that electron localization is due to its trapping at pentacoordinated sites, mostly present in the surface shell region. The present demonstration of fs hard X-ray absorption capabilities opens the way to a detailed description of the charge carrier dynamics in transition metal oxides.
Background
Patients undergoing surgery for soft tissue sarcoma have high morbidity rates, particularly after preoperative radiation therapy (RT). An enhanced recovery after surgery (ERAS) programme ...may improve perioperative outcomes in abdominal surgery. This study reported outcomes of an ERAS programme tailored to patients with soft tissue sarcoma.
Methods
A prospective ERAS protocol was implemented in 2015 at a high‐volume sarcoma centre. Patients treated within the ERAS programme from 2015 to 2018 were case‐matched retrospectively with patients treated between 2012 and 2018 without use of the protocol, matched by surgical site, surgeon, sarcoma histology and preoperative RT treatment. Postoperative outcomes, specifically wound complications and duration of hospital stay, were reported.
Results
In total, 234 patients treated within the ERAS programme were matched with 237 who were not. The ERAS group had lower wound dehiscence rates overall (2 of 234 (0·9 per cent) versus 31 of 237 (13·1 per cent); P < 0·001), after preoperative RT (0 of 41 versus 11 of 51; P = 0·004) and after extremity sarcoma surgery (0 of 54 versus 6 of 56; P = 0·040) compared with the non‐ERAS group. Rates of postoperative ileus or obstruction were lower in the ERAS group (21 of 234 (9·9 per cent) versus 40 of 237 (16·9 per cent); P = 0·016) and in those with retroperitoneal sarcoma (4 of 36 versus 15 of 36; P = 0·007). Duration of hospital stay was shorter in the ERAS group (median 5 (range 0–36) versus 6 (0–67) days; P = 0·003).
Conclusion
Treatment within an ERAS protocol for patients with soft tissue sarcoma was associated with lower morbidity and shorter hospital stay.
Antecedentes
Los pacientes sometidos a cirugía por sarcoma de tejido blando (soft tissue sarcoma, STS) tienen altas tasas de morbilidad, particularmente después de la radioterapia preoperatoria (RT). El programa de recuperación intensificada después de la cirugía (enhanced recovery after surgery, ERAS) puede mejorar los resultados perioperatorios en la cirugía abdominal. Este estudio analizó los resultados de un programa ERAS diseñado para pacientes con STS.
Métodos
Se implementó un protocolo prospectivo ERAS en el año 2015 en un centro de alto volumen de sarcomas. Los pacientes en ERAS desde 2015 hasta 2018 fueron emparejados retrospectivamente con pacientes sin ERAS desde 2012 hasta 2018, según la localización quirúrgica, el cirujano, la histología del sarcoma y el tratamiento con RT preoperatoria. Se analizaron los resultados postoperatorios, específicamente las complicaciones de la herida y la duración de la estancia hospitalaria (length of stay, LOS).
Resultados
En total, 234 pacientes tratados con ERAS se compararon con 237 pacientes no tratados con ERAS. Los pacientes con ERAS tuvieron tasas globales más bajas de dehiscencia de la herida (2 (0,9%) versus 31 (13,1%), P < 0,001)), después de la RT preoperatoria (0 versus 11 (21,6%), P = 0,004)), y después de la cirugía de STS de extremidades (0 versus 6 (0,7%), P = 0,04)) en comparación con los pacientes no ERAS. Las tasas de íleo u obstrucción postoperatorias fueron más bajas en el grupo ERAS (21 (9,9%) versus 40 (16,9%), P = 0,02)) y en aquellos pacientes con sarcoma retroperitoneal (4 (11,1%) versus 15 (41,7%), P = 0,007)). La mediana (rango) de la LOS fue más corta en los pacientes con ERAS que fue de 5 (0‐36) días que en los pacientes sin ERAS que fue de 6 (0‐67) días (P = 0,003).
Conclusión
ERAS para pacientes con STS se asoció con una menor morbilidad y una estancia hospitalaria más corta.
An enhanced recovery after surgery (ERAS) protocol may diminish the adverse effects of postoperative wound complications associated with preoperative radiotherapy. Further studies validating these findings may lead to a consensus on treatment algorithms for patients with trunk and extremity soft tissue sarcoma. The results support the use of ERAS to minimize acute postoperative complications and reduce duration of hospital stay.
Organized care better
The FAST was a factorial trial in first-line treatment of advanced non-small-cell lung cancer (NSCLC), addressing the role of replacing cisplatin with a non-platinum agent. The prognostic and ...predictive effect of ERCC1/BRCA1 expression and ERCC1/XPD/XRCC1-3 gene polymorphisms on outcomes of patients was examined.
Patients were randomised to receive treatment with or without cisplatin. ERCC1/BRCA1 expression was determined by immunohistochemistry. ERCC1 (C8092A, C118T), XPD (Lys751Gln), XRCC1 (Arg399Gln) and XRCC3 (Thr241Met) gene polymorphisms were evaluated on tumour DNA by TaqMan allelic discrimination assay.
Tumour samples were available from 110 of 433 patients enrolled: 54.7% were ERCC1 positive and 51.4% were BRCA1 positive. Overall, ERCC1-negative patients had better response rate (P=0.004), progression-free survival (P=0.023) and overall survival (P=0.012) compared with positive ones, with no statistically significant treatment interaction. The BRCA1-positive patients showed numerically better outcomes, although not statistically significant, with no treatment interaction. Among DNA repair gene polymorphisms, only XRCC1 Gln/Gln genotype evidenced a potential prognostic role (P=0.036).
This study confirms the prognostic role of ERCC1 expression and XRCC1 (Arg399Gln) polymorphism in advanced NSCLC treated with first-line chemotherapy. None of these biomarkers was shown to be a specific predictive factor of cisplatin efficacy.
Lesch-Nyhan disease (LND) is a rare X-linked genetic disorder, with complete hypoxanthine-guanine phosphoribosyltransferase (HGPRT) deficiency, uric acid (UA), hypoxanthine and xanthine accumulation, ...and a devastating neurologic syndrome. UA excess, causing renal failure, is commonly decreased by xanthine oxidoreductase (XOR) inhibitors, such as allopurinol, yielding a xanthine and hypoxanthine increase. Xanthine accumulation may result in renal stones, while hypoxanthine excess seems involved in the neurological disorder. Inhibition of purine nucleoside phosphorylase (PNP) represents a different strategy for lowering urate. PNP catalyzes the cleavage of purine ribo- and d-ribo-nucleosides into ribose/deoxyribose phosphate and free bases, starting catabolism to uric acid. Clinical trials demonstrated that PNP inhibitors, initially developed as anticancer drugs, lowered UA in some gouty patients, in association or not with allopurinol. The present study tested the reliability of an analogue of immucillin-G (C1a), a PNP inhibitor, as a therapy for urate, hypoxanthine, and xanthine excess in LND patients by blocking hypoxanthine production upstream. The therapeutic aim is to limit the administration of XOR inhibitors to LND patients by supplying the PNP inhibitor in low doses, avoiding d-nucleoside toxicity. We report studies conducted in primary cultures of skin fibroblasts from controls and LND patients grown in the presence of the PNP inhibitor. Cell viability, oxypurine release in culture medium, and endocellular nucleotide pattern have been monitored in different growth conditions (inhibitor concentration, time, added inosine). Our results demonstrate effective PNP inhibition by low inhibitor concentration, with reduced hypoxanthine release, and no appreciable toxicity in control or patient cells, suggesting a new therapeutic strategy for LND hyperuricemia.
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