141 research outputs found
Weyl Gravity in Covariant Hamiltonian Formalism
We find covariant canonical formalism for Weyl invariant gravity. We discuss
constraint structure of this theory and its gauge fixed form.Comment: 19 page
A Bond-Order Potential Incorporating Analytic Screening Functions for the Molybdenum Silicides
The intermetallic compound MoSi2, which adopts the C11b crystal structure, and related alloys exhibit an excellent corrosion resistance at high temperatures but tend to be brittle at room and even relatively high temperatures. The limited ductility of MoSi2 in ambient conditions along with the anomalous temperature dependence of the critical resolved shear stress (CRSS) of the {110)\u3c111], {011)\u3c100] and {010)\u3c100] slip systems and departure from Schmid law behavior of the {013)\u3c331] slip system can all be attributed to complex dislocation core structures. We have therefore developed a Bond-Order Potential (BOP) for MoSi2 for use in the atomistic simulation of dislocations and other extended defects. BOPs are a real-space, O(N), two-center orthogonal tight-binding formalism that are naturally able to describe systems with mixed metallic and covalent bonding. In this development novel analytic screening functions have been adopted to properly describe the environmental dependence of bond integrals in the open, bcc-based C11b crystal structure. A many-body repulsive term is included in the model that allows us to fit the elastic constants and negative Cauchy pressures of MoSi2. Due to the internal degree of freedom in the position of the Si atoms in the C11b structure which is a function of volume, it was necessary to adopt a self-consistent procedure in the fitting of the BOP. The constructed BOP is found to be an excellent description of cohesion in C11bMoSi2 and we have carefully assessed its transferability to other crystal structures and stoichiometries, notably C40, C49 and C54 MoSi2, A15 and D03 Mo3Si and D8m Mo5Si3 by comparing with ab initio structural optimizations
Population pharmacokinetics of pomalidomide in patients with relapsed or refractory multiple myeloma with various degrees of impaired renal function
Systematic analysis of the IL‐17 receptor signalosome reveals a robust regulatory feedback loop
The role of motorized transport and mobile phones in the diffusion of agricultural information in Tanggamus Regency, Indonesia
A randomized phase 3 trial of zanubrutinib vs ibrutinib in symptomatic Waldenström macroglobulinemia: the ASPEN study
Se trata de la publicación del estudio de fase 3 ASPEN que comparó en pacientes con macro-globulinemia de Waldenström (WM) la eficacia y la seguridad de ibrutinib, un inhibidor de la tirosi-na quinasa Bruton (BTK) de primera generación, familia que ha demostrado ser un tratamiento eficaz en estos pacientes, frente a zanubrutinib, un nuevo inhibidor de BTK de 2ª generación, altamente selectivo. Los pacientes con enfermedad MYD88L265P se asignaron al azar 1:1 al tratamiento con ibrutinib o zanubrutinib. El criterio principal de valoración fue la proporción de pa-cientes que lograron una respuesta completa (RC) o una respuesta parcial muy buena (RPMB) mediante una revisión independiente. Los criterios secundarios clave de valoración incluyeron la tasa de respuesta mayor (RM), la supervivencia libre de progresión (SLP), la duración de la res-puesta (DR), la carga de la enfermedad y la seguridad. Se randomizaron 201 pacientes y 199 recibieron al menos 1 dosis del tratamiento del estudio. Veintinueve (28%) pacientes tratados con zanubrutinib y 19 (19%) pacientes tratados con ibrutinib lograron una RPMB, diferencia que no alcanzó la significación estadística (P = 0,09). Las RM fueron del 77% y del 78%, respectivamen-te. No se alcanzó la mediana de DR y SLP, ya que el 84% y el 85% de los pacientes tratados con ibrutinib y zanubrutinib estaban libres de progresión a los 18 meses. La fibrilación auricular, hema-tomas, diarrea, edema periférico, hemorragia, espasmos musculares y neumonía, así como los eventos adversos que condujeron a interrumpir el tratamiento, fueron menos frecuentes entre los receptores de zanubrutinib. La incidencia de neutropenia fue mayor con zanubrutinib, aunque las tasas de infección de grado ≥3 fueron similares en ambos grupos (1,2 y 1,1 eventos por 100 me-ses-persona). Estos resultados demuestran que zanubrutinib e ibrutinib son altamente efectivos en el tratamiento de la WM, pero zanubrutinib se asoció con menor toxicidad y una tendencia hacia una mejor calidad de respuesta y menos toxicidad, particularmente toxicidad cardiovascular.[EN]Bruton tyrosine kinase (BTK) inhibition is an effective treatment approach for patients with Waldenström macroglobulinemia (WM). The phase 3 ASPEN study compared the efficacy and safety of ibrutinib, a first-generation BTK inhibitor, with zanubrutinib, a novel highly selective BTK inhibitor, in patients with WM. Patients with MYD88L265P disease were randomly assigned 1:1 to treatment with ibrutinib or zanubrutinib. The primary end point was the proportion of patients achieving a complete response (CR) or a very good partial response (VGPR) by independent review. Key secondary end points included major response rate (MRR), progression-free survival (PFS), duration of response (DOR), disease burden, and safety. A total of 201 patients were randomized, and 199 received ≥1 dose of study treatment. No patient achieved a CR. Twenty-nine (28%) zanubrutinib patients and 19 (19%) ibrutinib patients achieved a VGPR, a nonstatistically significant difference (P = .09). MRRs were 77% and 78%, respectively. Median DOR and PFS were not reached; 84% and 85% of ibrutinib and zanubrutinib patients were progression free at 18 months. Atrial fibrillation, contusion, diarrhea, peripheral edema, hemorrhage, muscle spasms, and pneumonia, as well as adverse events leading to treatment discontinuation, were less common among zanubrutinib recipients. Incidence of neutropenia was higher with zanubrutinib, although grade ≥3 infection rates were similar in both arms (1.2 and 1.1 events per 100 person-months). These results demonstrate that zanubrutinib and ibrutinib are highly effective in the treatment of WM, but zanubrutinib treatment was associated with a trend toward better response quality and less toxicity, particularly cardiovascular toxicity.BeiGene CoBeiGene C
High proportion of recurrent germline mutations in the BRCA1 gene in breast and ovarian cancer patients from the Prague area
BACKGROUND: Germline mutations in the BRCA1 and BRCA2 genes have been shown to account for the majority of hereditary breast and ovarian cancers. The purpose of our study was to estimate the incidence and spectrum of pathogenic mutations in BRCA1/2 genes in high-risk Czech families. METHODS: A total of 96 Czech families with recurrent breast and/or ovarian cancer and 55 patients considered to be at high-risk but with no reported family history of cancer were screened for mutations in the BRCA1/2 genes. The entire coding sequence of each gene was analyzed using a combination of the protein truncation test and direct DNA sequencing. RESULTS: A total of 35 mutations in the BRCA1/2 genes were identified in high-risk families (36.5%). Pathogenic mutations were found in 23.3% of breast cancer families and in 59.4% of families with the occurrence of both breast and ovarian cancer. In addition, four mutations were detected in 31 (12.9%) women with early onset breast cancer. One mutation was detected in seven (14.3%) patients affected with both a primary breast and ovarian cancer and another in three (33.3%) patients with a bilateral breast cancer. A total of 3 mutations in BRCA1 were identified among 14 (21.4%) women with a medullary breast carcinoma. Of 151 analyzed individuals, 35 (23.2%) carried a BRCA1 mutation and 9 (6.0%) a BRCA2 mutation. One novel truncating mutation was found in BRCA1 (c.1747A>T) and two in BRCA2 (c.3939delC and c.5763dupT). The 35 identified BRCA1 mutations comprised 13 different alterations. Three recurrent mutations accounted for 71.4% of unrelated individuals with detected gene alterations. The BRCA1 c.5266dupC (5382insC) was detected in 51.4% of mutation positive women. The mutations c.3700_3704del5 and c.181T>G (300T>G) contributed to 11.4% and 8.6% of pathogenic mutations, respectively. A total of eight different mutations were identified in BRCA2. The novel c.5763dupT mutation, which appeared in two unrelated families, was the only recurrent alteration of the BRCA2 gene identified in this study. CONCLUSION: Mutational analysis of BRCA1/2 genes in 151 high-risk patients characterized the spectrum of gene alterations and demonstrated the dominant role of the BRCA1 c.5266dupC allele in hereditary breast and ovarian cancer
Outcome in patients perceived as receiving excessive care across different ethical climates: a prospective study in 68 intensive care units in Europe and the USA
Purpose: Whether the quality of the ethical climate in the intensive care unit (ICU) improves the identification of patients receiving excessive care and affects patient outcomes is unknown. Methods: In this prospective observational study, perceptions of excessive care (PECs) by clinicians working in 68 ICUs in Europe and the USA were collected daily during a 28-day period. The quality of the ethical climate in the ICUs was assessed via a validated questionnaire. We compared the combined endpoint (death, not at home or poor quality of life at 1 year) of patients with PECs and the time from PECs until written treatment-limitation decisions (TLDs) and death across the four climates defined via cluster analysis. Results: Of the 4747 eligible clinicians, 2992 (63%) evaluated the ethical climate in their ICU. Of the 321 and 623 patients not admitted for monitoring only in ICUs with a good (n = 12, 18%) and poor (n = 24, 35%) climate, 36 (11%) and 74 (12%), respectively were identified with PECs by at least two clinicians. Of the 35 and 71 identified patients with an available combined endpoint, 100% (95% CI 90.0–1.00) and 85.9% (75.4–92.0) (P = 0.02) attained that endpoint. The risk of death (HR 1.88, 95% CI 1.20–2.92) or receiving a written TLD (HR 2.32, CI 1.11–4.85) in patients with PECs by at least two clinicians was higher in ICUs with a good climate than in those with a poor one. The differences between ICUs with an average climate, with (n = 12, 18%) or without (n = 20, 29%) nursing involvement at the end of life, and ICUs with a poor climate were less obvious but still in favour of the former. Conclusion: Enhancing the quality of the ethical climate in the ICU may improve both the identification of patients receiving excessive care and the decision-making process at the end of life
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