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1.
J Phys Condens Matter ; 35(12)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36652715

RESUMO

In theoretical analyses of ultrafast spin dynamics simulated phenomena are commonly discussed in terms of observables. In this paper we report on possible benefits of complementing such studies by quantum state (QS) measures. These measures quantify specific properties of QSs, e.g. distance in Hilbert space and mixing. For Co/Cu heterostructures illuminated by femtosecond laser pulses, we discuss the general behavior of selected measures, but address in particular the degree of perturbation by a laser pulse. It turns out that the measures are especially sensitive to variations of the polarization of a laser pulse and the sample composition. Moreover, they are closely linked to magnetization and number of photo-excited electrons.

2.
Personal Disord ; 14(3): 287-299, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35511574

RESUMO

According to the alternative model for personality disorders (AMPD) of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), a moderate or greater impairment in personality functioning is the essential criterion for a personality disorder diagnosis. Personality functioning is operationalized in the Level of Personality Functioning Scale via 4 domains (identity, self-direction, empathy, and intimacy) and 2 higher order dimensions (self and interpersonal functioning). The current study examined the reliability (interrater, test-retest), structure, and validity (convergent, discriminant, and incremental) of the Structured Clinical Interview for the AMPD-Module I (SCID-5-AMPD-I). A clinical sample (n = 121) completed the SCID-5-AMPD-I, along with an interview for DSM-5 Section II personality disorders and self-reports for personality pathology (personality functioning, personality organization, personality structure, and pathological personality traits) and other forms of psychopathology (depression, anxiety, somatization, and general disability). Interrater and test-retest reliability was excellent for overall personality functioning, the higher order dimensions, and the domains, except for the empathy domain in the test-retest condition. Factor analyses suggest that personality functioning is an essentially unidimensional construct. Personality functioning demonstrated high convergence with other forms of personality pathology and showed good discriminant validity in relation to depression, anxiety, and somatization but not in relation to the broader construct of general disability. Personality functioning (Criterion A) showed incremental validity over pathological personality traits (Criterion B) in predicting interview-assessed DSM-5 Section II personality disorders but not in predicting self-reported personality and general psychopathology. The present study suggests that the SCID-5-AMPD-I is a viable measure for personality functioning. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Transtornos da Personalidade , Personalidade , Humanos , Manual Diagnóstico e Estatístico de Transtornos Mentais , Reprodutibilidade dos Testes , Transtornos da Personalidade/diagnóstico , Inventário de Personalidade
3.
Sci Adv ; 8(24): eabo5930, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35704587

RESUMO

The current-induced spin-orbit torque switching of ferromagnets has had huge impact in spintronics. However, short spin-diffusion lengths limit the thickness of switchable ferromagnetic layers, thereby limiting their thermal stability. Here, we report a previously unobserved seeded spin-orbit torque (SSOT) by which current can set the magnetic states of even thick layers of the chiral kagome antiferromagnet Mn3Sn. The mechanism involves setting the orientation of the antiferromagnetic domains in a thin region at the interface with spin currents arising from an adjacent heavy metal while also heating the layer above its magnetic ordering temperature. This interface region seeds the resulting spin texture of the entire layer as it cools down and, thereby, overcomes the thickness limitation of conventional spin-orbit torques. SSOT switching in Mn3Sn can be extended beyond chiral antiferromagnets to diverse magnetic systems and provides a path toward the development of highly efficient, high-speed, and thermally stable spintronic devices.

4.
HPB (Oxford) ; 20(4): 289-296, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29366814

RESUMO

BACKGROUND: Intraoperative tumor manipulation may induce the dissemination of occult peritoneal tumor cells (OPTC) into the peritoneal cavity. METHODS: A systematic review was performed in the PubMed, Embase and Cochrane databases from inception to March 15, 2017. Eligible were studies that analyzed the presence of OPTC in peritoneal fluid, by any method, both before and after resection in adults who underwent intentionally curative pancreatic resection for histopathologically confirmed pancreatic ductal adenocarcinoma in absence of macroscopic peritoneal metastases. RESULTS: Four studies with 138 patients met the inclusion criteria. The pooled rate of OPTC prior to tumor manipulation was 8% (95% CI 2%-24%). The pooled detection rate of OPTC in patients in whom OPTC became detectable only after tumor manipulation was 33% (95% CI 15-58%). Only one study (28 patients) reported on survival, which was worse in patients with OPTC (median 11.1 months versus 30.3 months; p = 0.030). CONCLUSION: This systematic review suggests that tumor manipulation induces OPTC in one third of patients with pancreatic cancer. Since data on survival are lacking, future studies should determine the prognostic consequences of tumor manipulation, including the potential therapeutic effect of 'no-touch' and minimally invasive resection strategies.


Assuntos
Carcinoma Ductal Pancreático/secundário , Carcinoma Ductal Pancreático/cirurgia , Inoculação de Neoplasia , Pancreatectomia/efeitos adversos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/efeitos adversos , Neoplasias Peritoneais/secundário , Idoso , Carcinoma Ductal Pancreático/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatectomia/mortalidade , Neoplasias Pancreáticas/mortalidade , Pancreaticoduodenectomia/mortalidade , Neoplasias Peritoneais/mortalidade , Fatores de Risco , Resultado do Tratamento
5.
Trials ; 17(1): 127, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26955809

RESUMO

BACKGROUND: Pancreatic cancer is the fourth largest cause of cancer death in the United States and Europe with over 100,000 deaths per year in Europe alone. The overall 5-year survival ranges from 2-7 % and has hardly improved over the last two decades. Approximately 15 % of all patients have resectable disease at diagnosis, and of those, only a subgroup has a resectable tumour at surgical exploration. Data from cohort studies have suggested that outcome can be improved by preoperative radiochemotherapy, but data from well-designed randomized studies are lacking. Our PREOPANC phase III trial aims to test the hypothesis that median overall survival of patients with resectable or borderline resectable pancreatic cancer can be improved with preoperative radiochemotherapy. METHODS/DESIGN: The PREOPANC trial is a randomized, controlled, multicentric superiority trial, initiated by the Dutch Pancreatic Cancer Group. Patients with (borderline) resectable pancreatic cancer are randomized to A: direct explorative laparotomy or B: after negative diagnostic laparoscopy, preoperative radiochemotherapy, followed by explorative laparotomy. A hypofractionated radiation scheme of 15 fractions of 2.4 gray (Gy) is combined with a course of gemcitabine, 1,000 mg/m(2)/dose on days 1, 8 and 15, preceded and followed by a modified course of gemcitabine. The target volumes of radiation are delineated on a 4D CT scan, where at least 95 % of the prescribed dose of 36 Gy in 15 fractions should cover 98 % of the planning target volume. Standard adjuvant chemotherapy is administered in both treatment arms after resection (six cycles in arm A and four in arm B). In total, 244 patients will be randomized in 17 hospitals in the Netherlands. The primary endpoint is overall survival by intention to treat. Secondary endpoints are (R0) resection rate, disease-free survival, time to locoregional recurrence or distant metastases and perioperative complications. Secondary endpoints for the experimental arm are toxicity and radiologic and pathologic response. DISCUSSION: The PREOPANC trial is designed to investigate whether preoperative radiochemotherapy improves overall survival by means of increased (R0) resection rates in patients with resectable or borderline resectable pancreatic cancer. TRIAL REGISTRATION: Trial open for accrual: 3 April 2013 The Netherlands National Trial Register - NTR3709 (8 November 2012) EU Clinical Trials Register - 2012-003181-40 (11 December 2012).


Assuntos
Adenocarcinoma/terapia , Antimetabólitos Antineoplásicos/administração & dosagem , Quimiorradioterapia Adjuvante , Desoxicitidina/análogos & derivados , Terapia Neoadjuvante , Pancreatectomia , Neoplasias Pancreáticas/terapia , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Antimetabólitos Antineoplásicos/efeitos adversos , Quimiorradioterapia Adjuvante/efeitos adversos , Quimiorradioterapia Adjuvante/mortalidade , Protocolos Clínicos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Intervalo Livre de Doença , Esquema de Medicação , Humanos , Estimativa de Kaplan-Meier , Terapia Neoadjuvante/efeitos adversos , Terapia Neoadjuvante/mortalidade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Países Baixos , Pancreatectomia/efeitos adversos , Pancreatectomia/mortalidade , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Hipofracionamento da Dose de Radiação , Projetos de Pesquisa , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral , Gencitabina
6.
J Biol Chem ; 288(26): 18825-33, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23671285

RESUMO

Fertilization in animals is a complex sequence of several biochemical events beginning with the insemination into the female reproductive tract and, finally, leading to embryogenesis. Studies by Kitajima and co-workers (Miyata, S., Sato, C., and Kitajima, K. (2007) Trends Glycosci. Glyc, 19, 85-98) demonstrated the presence of polysialic acid (polySia) on sea urchin sperm. Based on these results, we became interested in the potential involvement of sialic acid polymers in mammalian fertilization. Therefore, we isolated human sperm and performed analyses, including Western blotting and mild 1,2-diamino-4,5-methylenedioxybenzene-HPLC, that revealed the presence α2,8-linked polySia chains. Further analysis by a glyco-proteomics approach led to the identification of two polySia carriers. Interestingly, besides the neural cell adhesion molecule, the polysialyltransferase ST8SiaII has also been found to be a target for polysialylation. Further analysis of testis and epididymis tissue sections demonstrated that only epithelial cells of the caput were polySia-positive. During the epididymal transit, polySia carriers were partially integrated into the sperm membrane of the postacrosomal region. Because polySia is known to counteract histone as well as neutrophil extracellular trap-mediated cytotoxicity against host cells, which plays a role after insemination, we propose that polySia in semen represents a cytoprotective element to increase the number of vital sperm.


Assuntos
Moléculas de Adesão de Célula Nervosa/metabolismo , Processamento de Proteína Pós-Traducional , Sêmen/metabolismo , Ácidos Siálicos/metabolismo , Sialiltransferases/metabolismo , Motivos de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Epididimo/metabolismo , Feminino , Fertilização , Humanos , Masculino , Camundongos , Microscopia de Fluorescência , Proteômica/métodos , Ratos , Espermatozoides/metabolismo
7.
Dig Surg ; 29(1): 35-42, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22441618

RESUMO

BACKGROUND: Vascular occlusion can be applied during liver resection to reduce blood loss. Herein, we provide an update of the current evidence concerning vascular occlusion. METHODS: A systematic literature search was conducted to review the effects of liver in- and outflow occlusion techniques during liver resection, focusing on blood loss and hepatic ischemia-reperfusion injury. RESULTS: The Pringle maneuver (PM) is effective in controlling blood loss; however, there is no indication for routine vascular clamping during hepatic resection in uncomplicated patients. During complex resections and in patients with abnormal liver parenchyma, the intermittent PM is preferred over continuous clamping. Total hepatic vascular exclusion (THVE) is indicated only in resection of tumors involving the inferior caval vein or the caval hepatic junction. THVE can be applied with the preservation of caval vein flow. This mode of selective hepatic vascular exclusion results in less blood loss in combination with the PM. CONCLUSION: If clamping is necessary during complex resections or in abnormal liver parenchyma, intermittent PM is advised. THVE or selective hepatic vascular exclusion may be considered in tumors involving the inferior caval vein or the caval hepatic junction. There is no evidence supporting the use of ischemic preconditioning, maintenance of a low central venous pressure or of pharmacological interventions during liver resection.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Hepatectomia/métodos , Precondicionamento Isquêmico , Fígado/irrigação sanguínea , Oclusão com Balão/efeitos adversos , Constrição , Hepatectomia/efeitos adversos , Humanos , Isquemia/etiologia , Isquemia/prevenção & controle , Circulação Hepática , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/prevenção & controle
8.
Dig Surg ; 29(1): 48-53, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22441620

RESUMO

BACKGROUND: Biliary leakage after liver resection continues to be reported. Management of bile leakage has changed in recent years, with nowadays non-surgical procedures as the preferred treatment. METHODS: Biliary leakage and management were assessed in 381 patients who underwent liver resection between January 2005 and April 2011. RESULTS: The overall rate of biliary leakage after liver resection was 5.0%, with a higher incidence in patients who had undergone concomitant hepaticojejunostomy (HJ; 13.6 vs. 3.2%). Hospital stay (p = 0.047), major resections (p = 0.018), operation time (p = 0.011), and relaparotomy (p = 0.002) were risk factors for postoperative bile leakage. Multivariate analysis identified relaparotomy as an independent factor (OR 4.216, p = 0.034). Bile leakage in patients without HJ (n = 10) was managed in 6 patients by percutaneous transhepatic biliary drainage (PTD), and in 3 patients by endoscopic drainage. One patient was treated surgically. All patients with an HJ and postoperative bile leakage (n = 9) underwent PTD. CONCLUSION: The incidence of posthepatectomy biliary leakage has decreased over time, while PTD and endoscopic stenting are effective treatment modalities. PTD is the treatment of choice in bile leakage after resection combined with HJ.


Assuntos
Fístula Anastomótica/terapia , Hepatectomia/efeitos adversos , Adulto , Idoso , Ductos Biliares , Colangiopancreatografia Retrógrada Endoscópica , Drenagem , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reoperação/efeitos adversos , Estudos Retrospectivos , Stents , Fatores de Tempo , Adulto Jovem
9.
Dig Surg ; 28(2): 141-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21540600

RESUMO

BACKGROUND: Hilar resection in combination with extended liver resections has resulted in a higher rate of R0 resections and increased survival in patients with hilar cholangiocarcinoma (HCCA). This aggressive surgical approach is, however, associated with high rates of operative morbidity and mortality, largely due to postresectional liver failure. We previously reported a series after resection of HCCA in which R0 resection rate was 59% with a mortality rate of 10%. In this study, we assessed mortality of extended liver resections after optimizing liver functional reserve and application of parenchyma-sparing techniques. METHODS: From 2008 until June 2010, 41 consecutive patients underwent resection on the suspicion of HCCA. Preoperative workup included staging laparoscopy, preoperative biliary drainage, assessment of volume/function of future remnant liver and radiation therapy to prevent seeding metastases. Modified right and left extended hemihepatectomies were performed preserving parts of segments 4 and 8, respectively, while pursuing complete excision of the tumor. Outcomes of resection were evaluated. RESULTS: The majority of resections (78%) were performed for Bismuth type III-IV tumors. Preoperative biliary drainage was undertaken in 37 (90%) patients. Hilar resection in combination with liver resection was performed in 35 (85%) patients. Of these resections, 61% were modified extended resections including central liver resections. The R0 resection rate was 92%. Postoperative morbidity and mortality rates were 54 and 7%, respectively. CONCLUSION: Strategies to optimize liver function and to reduce removal of functional liver parenchyma were associated with a decrease in mortality (7%) while undertaking extended resection for HCCA with an R0 resection rate of 92%.


Assuntos
Colangiocarcinoma/patologia , Colangiocarcinoma/cirurgia , Hepatectomia/mortalidade , Hepatectomia/métodos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Bile , Colangiocarcinoma/mortalidade , Drenagem/métodos , Mortalidade Hospitalar , Humanos , Fígado/fisiologia , Testes de Função Hepática , Neoplasias Hepáticas/mortalidade
10.
Dig Surg ; 22(3): 191-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16137997

RESUMO

AIM OF THE STUDY: In two institutions, a retrospective analysis was performed on patients with histologically proven locally advanced pancreatic cancer without distant metastases. The aim of this analysis is to assess whether chemoradiotherapy provides survival benefit for patients with locally advanced pancreatic cancer. METHODS: Forty-five patients from the Erasmus Medical Centre (Erasmus MC), Rotterdam, received 5-fluorouracil (5-FU) and radiotherapy and, 38 patients from the Academic Medical Centre Amsterdam (AMC) were offered the best supportive care. Radiotherapy consisted of 50 Gy external upper abdomen radiation in two courses, concomitant with intravenous 5-FU 25 mg/kg/ 24 h continuously on the first 4 days of each treatment course. RESULTS: The treatment protocol was completed in 38 of 45 patients (84%) without complications. Radiological response was evaluated in 38 patients. Ten patients (26%) showed a partial response, stable disease was seen in 6 (16%) patients and progressive disease in 22 (58%) patients. A second-look operation was performed in 8 of 10 patients (72%) showing a radiological response, in 3 patients the tumour could be resected. Median overall survival time for the Erasmus MC group (n = 45) was 9.8 months compared to 7.6 months when the best supportive care was given (AMC group, p = 0.04). CONCLUSION: Although overall survival remains poor, treatment with 5-FU and radiotherapy might benefit some patients with locally advanced pancreatic cancer.


Assuntos
Adenocarcinoma/terapia , Antineoplásicos/uso terapêutico , Fluoruracila/uso terapêutico , Neoplasias Pancreáticas/terapia , Radioterapia Adjuvante/métodos , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos do Sistema Digestório , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Análise de Sobrevida , Resultado do Tratamento
11.
J Comb Chem ; 6(3): 420-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15132603

RESUMO

FTIR spectroscopy in reflection mode combined with a focal plane array (FPA) detector was employed for high-throughput screening of activity of catalysts in n-pentane hydroisomerization. The reactor system was evaluated using reference catalysts Pt-MOR and gamma-alumina of known catalytic activity. By using the reflection setup, a higher degree of parallelization was possible, as compared to previous reports, in which transmission cells had been used. The 49-channel parallel reactor in combination with the FPA-IR optical setup was able to provide reliable information about the activity of different catalysts with relative data error of less than +/-20%.

12.
J Am Chem Soc ; 124(45): 13527-32, 2002 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-12418907

RESUMO

A new fast parallel detection method for stage I screening of solid catalysts has been developed. This method is based on the color change of organic dyes in the presence of either educts or reaction products in a reaction gas flow. As an example, NO decomposition and NO reduction with propylene under lean or rich conditions were studied. The presence of NO in a gas stream was detected by the color change from colorless to blue-green of filter paper impregnated with an organic dye, 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), which was placed in the gas stream after the catalyst bed. The catalyst library was made up of mixed metal oxides, synthesized by impregnation of activated carbon with metal oxide precursor solutions and subsequent combustion of the carbon matrix. Catalytic activity of these metal oxides was compared to platinum on gamma-alumina as a reference catalyst. The most active compounds were then studied in detail for their DeNO(x)properties in a high precision parallel flow test rig under a stationary and cyclic lean/reach operation. A new promising NO(x) storage catalyst was discovered.

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