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1.
Phys Rev Lett ; 130(24): 242501, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37390416

RESUMO

Excited-state spectroscopy from the first experiment at the Facility for Rare Isotope Beams (FRIB) is reported. A 24(2)-µs isomer was observed with the FRIB Decay Station initiator (FDSi) through a cascade of 224- and 401-keV γ rays in coincidence with ^{32}Na nuclei. This is the only known microsecond isomer (1 µs≤T_{1/2}<1 ms) in the region. This nucleus is at the heart of the N=20 island of shape inversion and is at the crossroads of the spherical shell-model, deformed shell-model, and ab initio theories. It can be represented as the coupling of a proton hole and neutron particle to ^{32}Mg, ^{32}Mg+π^{-1}+ν^{+1}. This odd-odd coupling and isomer formation provides a sensitive measure of the underlying shape degrees of freedom of ^{32}Mg, where the onset of spherical-to-deformed shape inversion begins with a low-lying deformed 2^{+} state at 885 keV and a low-lying shape-coexisting 0_{2}^{+} state at 1058 keV. We suggest two possible explanations for the 625-keV isomer in ^{32}Na: a 6^{-} spherical shape isomer that decays by E2 or a 0^{+} deformed spin isomer that decays by M2. The present results and calculations are most consistent with the latter, indicating that the low-lying states are dominated by deformation.


Assuntos
Núcleo Celular , Coração , Isótopos , Nêutrons
2.
Phys Rev Lett ; 129(21): 212501, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36461950

RESUMO

New half-lives for exotic isotopes approaching the neutron drip-line in the vicinity of N∼28 for Z=12-15 were measured at the Facility for Rare Isotope Beams (FRIB) with the FRIB decay station initiator. The first experimental results are compared to the latest quasiparticle random phase approximation and shell-model calculations. Overall, the measured half-lives are consistent with the available theoretical descriptions and suggest a well-developed region of deformation below ^{48}Ca in the N=28 isotones. The erosion of the Z=14 subshell closure in Si is experimentally confirmed at N=28, and a reduction in the ^{38}Mg half-life is observed as compared with its isotopic neighbors, which does not seem to be predicted well based on the decay energy and deformation trends. This highlights the need for both additional data in this very exotic region, and for more advanced theoretical efforts.

3.
Intern Med J ; 42(3): 260-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21118414

RESUMO

BACKGROUND: Recent data suggest that masked hypertension (MH) carries a cardiovascular risk similar to that of uncontrolled hypertension. AIMS: The objective of this study was to determine the prevalence and determinants of MH in patients treated for hypertension in a Canadian primary care setting. METHODS: Office blood pressure (OBP) was measured at baseline and after 3 months of valsartan-based therapy in 5636 hypertensive patients who had recorded their home blood pressure monitoring (HBPM) for seven consecutive days at month 3 using an Omron HEM-711 apparatus. MH was defined in nondiabetic patients as an OBP <140/90 mmHg and an HBPM ≥135/85 mmHg, and in those with diabetes as an OBP <130/80 mmHg and an HBPM ≥125/75 mmHg. RESULTS: Of the 5636 patients, 1025 had diabetes. OBP was controlled at 3 months in 268 (26.1%) of them, but 167 (62.3%) had MH. OBP was controlled in 2728 (59.1%) of the 4611 patients without diabetes, and 935 (34.3%) of them had MH. Overall, 1102 patients had MH, representing 36.8% of patients with controlled OBP and 19.6% of the entire hypertensive study population. Stepwise multiple logistic regression analysis in nondiabetic patients with controlled OBP at 3 months revealed that older age, male sex, higher body mass index and higher office systolic blood pressure were determinants of MH. CONCLUSION: Our results indicate that one of five hypertensive patients and more than one of three with controlled OBP will have MH. MH is associated with other cardiovascular risk factors, such as diabetes, and in nondiabetics, with male sex, older age and obesity.


Assuntos
Hipertensão Mascarada/epidemiologia , Atenção Primária à Saúde , Antagonistas Adrenérgicos beta/administração & dosagem , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/uso terapêutico , Monitorização Ambulatorial da Pressão Arterial , Doenças Cardiovasculares/epidemiologia , Comorbidade , Complicações do Diabetes/epidemiologia , Quimioterapia Combinada , Dislipidemias/epidemiologia , Feminino , Insuficiência Cardíaca/epidemiologia , Humanos , Hidroclorotiazida/administração & dosagem , Hidroclorotiazida/uso terapêutico , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Prevalência , Quebeque/epidemiologia , Risco , Tetrazóis/administração & dosagem , Tetrazóis/uso terapêutico , Valina/administração & dosagem , Valina/análogos & derivados , Valina/uso terapêutico , Valsartana , Hipertensão do Jaleco Branco/epidemiologia
4.
Inflammation ; 40(1): 259-274, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27896542

RESUMO

The Th1- and Treg cell-related immune responses play key roles in the modulation of Th2 cell-related allergic disorders. The aim was to evaluate the effects of CPG, MPLA, and BCG on the number of Th1-, Th2-, and Treg cell-related parameters in an animal model of asthma. BALB/c mice were divided into five groups and immunized subcutaneously (SC) on days 1, 15, and 22 with allergen Derp2. Three groups of mice were pretreated SC on days 0, 14, and 21 with CPG, CPG + MPLA, or CPG + BCG. All mice were then challenged intranasally with Derp2 on days 28-37. Blood samples were collected from the retro-orbital sinus, on days 0, 23, and 40. The serum levels of IL-4, IFN-γ, IgE, and IgG2a were measured using ELISA technique. The blood number of Th1 and Treg cells was determined using flow cytometry. At the sensitization phase, the number of Th1 and the serum levels of IFN-γ and IgG2a were significantly increased in the Derp2-sensitized group pretreated with CPG plus MPLA, and the number of Treg cells was significantly elevated in Derp2-sensitized mice pretreated with CPG or CPG plus MPLA as compared with that in Derp2-sensitized control mice. At the challenge phase, the number of Th1 was significantly elevated in Derp2-sensitized mice pretreated with CPG plus MPLA, CPG plus BCG, or CPG; the count of Treg cells was significantly increased in Derp2-sensitized mice pretreated with CPG plus BCG group; and the levels of IFN-γ and IgG2a were significantly enhanced in the Derp2-sensitized group pretreated with CPG plus MPLA in comparison with those in Derp2-sensitized control mice. The scores of inflammation and mucus secretion in the lung were significantly decreased in the Derp2-sensitized group pretreated with CPG, BCG, and CPG plus MPLA in comparison with those in the Derp2-sensitized control group. These results showed that BCG, MPLA, and CPG modulate Th1-, Th2-, and Treg-related parameters and ameliorate lung inflammatory parameters in a mouse model of asthma.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Asma/tratamento farmacológico , Imunomodulação/efeitos dos fármacos , Doença Aguda , Adjuvantes Imunológicos/administração & dosagem , Animais , Antígenos de Dermatophagoides , Asma/imunologia , Inflamação/terapia , Lipídeo A/análogos & derivados , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium bovis , Oligodesoxirribonucleotídeos , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th2/imunologia
5.
Hernia ; 19(5): 725-33, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25754219

RESUMO

PURPOSE: The selection of a laparoscopic approach for inguinal hernias varies among surgeons. It is unclear what is being done in actual practice. The purpose of this study was to report practice patterns for treatment of inguinal hernias among Quebec surgeons, and to identify factors that may be associated with the choice of operative approach. METHODS: We studied a population-based cohort of patients who underwent an inguinal hernia repair between 2007 and 2011 in Quebec, Canada. A generalized linear model was used to identify predictors associated with the selection of a laparoscopic approach. RESULTS: 49,657 inguinal hernias were repaired by 478 surgeons. Laparoscopic inguinal hernia repair (LIHR) was used in 8 % of all cases. LIHR was used to repair 28 % of bilateral hernias, 10 % of recurrent hernias, 6 % of unilateral hernias, and 4 % of incarcerated hernias. 268 (56 %) surgeons did not perform any laparoscopic repairs, and 11 (2 %) surgeons performed more than 100 repairs. These 11 surgeons performed 61 % of all laparoscopic cases. Patient factors significantly associated with having LIHR included younger age, fewer comorbidities, bilateral hernias, and recurrent hernias. CONCLUSION: An open approach is favored for all clinical scenarios, even for situations where published guidelines recommend a laparoscopic approach. Surgeons remain divided on the best technique for inguinal hernia repair: while more than half never perform LIHR, the small proportion who perform many use the technique for a large proportion of their cases. There appears to be a gap between the best practices put forth in guidelines and what surgeons are doing in actual practice. Identification of barriers to the broader uptake of LIHR may help inform the design of educational programs to train those who have the desire to offer this technique for certain cases, and have the volume to overcome the learning curve.


Assuntos
Hérnia Inguinal/cirurgia , Herniorrafia , Laparoscopia , Padrões de Prática Médica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Hérnia Inguinal/epidemiologia , Hérnia Inguinal/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Quebeque/epidemiologia , Adulto Jovem
6.
Melanoma Res ; 7(1): 32-42, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9067963

RESUMO

The constitutive and cytokine-mediated expression of MHC class I and II antigens and intercellular adhesion molecule-1 (ICAM-1) was evaluated on eight human melanoma cell lines derived from primary and metastatic malignancies from patients (WM human melanoma series) including three pairs of related cell lines derived from the same individual. The cytokines IL-1 beta, IL-4, IL-6, TNF alpha, TGF beta 2, IFN gamma and IFN alpha were assessed for their ability to modulate the expression of cell surface antigens. MHC class I and class II antigen expression was unregulated by IFN gamma, IFN alpha and/or TNF alpha in cell lines established from primary melanoma. In contrast the cell lines derived from metastatic deposits did not show an increase in expression of MHC antigens in response to these cytokines. Both primary and metastatic WM cell lines were shown to be resistant to spontaneous natural killer cell (NK) activity, but susceptible to effector lymphocytes mediating lymphotine activated killer (LAK) cytotoxicity as a result of activation by IL-2. Although the constitutive and cytokine-induced level of expression of ICAM-1 and MHC antigens varied between paired primary and metastatic cell lines, this did not correlate with susceptibility of the cell line target to NK or LAK cytotoxicity. Whereas the IFNs, TNF alpha, TGF beta 2 and IL-1 beta differentially modulated the expression of ICAM-1 and MHC class I, treatment with IFNs (but not IL-1 beta, TNF alpha or TGF beta 2) resulted in a significant reduction in the sensitivity of the melanoma cells to NK and LAK cytotoxicity. Constitutive ICAM-1 expression was positively correlated with the ability of WM cell lines to colonise the lungs of SCID mice upon i.v. injection. The acquisition of cytokine resistance and inability to demonstrate enhanced cell surface expression may represent an important feature associated with the development of the metastatic phenotype.


Assuntos
Antígenos de Neoplasias/metabolismo , Citocinas/farmacologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Molécula 1 de Adesão Intercelular/imunologia , Melanoma/metabolismo , Animais , Antígenos de Neoplasias/imunologia , Citotoxicidade Imunológica , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Neoplasias Pulmonares/secundário , Linfócitos/imunologia , Melanoma/imunologia , Camundongos , Camundongos SCID , Células Tumorais Cultivadas/efeitos dos fármacos
7.
Med Oncol ; 30(1): 377, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23275118

RESUMO

To determine whether metabolic or pathological response to preoperative chemotherapy can predict the relapse-free survival of gastroesophageal adenocarcinoma patients treated on a perioperative chemotherapy protocol. The prospectively collected data of a recently reported phase II trial of perioperative DCF chemotherapy (docetaxel/cisplatin/5-fluorouracil) were analyzed. Median relapse-free survival (RFS) was compared with the Wilcoxon rank-sum test between responders and non-responders according to defined metabolic (reduction in maximum standard uptake value of at least 35 %) and pathological (greater than 50 % tumor regression or ypN(0) status) criteria. A double-sided p value equal or inferior to 0.05 was considered significant. Patients were followed for a median of 807 days (95 % CI: 607-896). RFS was 576 days in metabolic non-responders versus not reached in metabolic responders (p 0.009) and 562 days in ypN+ versus not reached in ypN(0) patients (p 0.045). No statistically significant RFS difference was seen between low and high pathologic responders classified according to tumor regression criteria, although a trend was observed in favor of high pathologic responders. Simple metabolic and pathologic criteria used for the assessment of response to the preoperative part of perioperative chemotherapy can help to estimate the outcome of gastroesophageal adenocarcinoma patients.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Intervalo Livre de Doença , Docetaxel , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/cirurgia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Resultado do Tratamento , Adulto Jovem
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