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1.
Phys Rev Lett ; 128(17): 172501, 2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35570452

RESUMEN

In the exothermic process of fission decay, an atomic nucleus splits into two or more independent fragments. Several aspects of nuclear fission are not properly understood, in particular the formation of the neck between the nascent fragments, and the subsequent mechanism of scission into two or more independent fragments. Using an implementation of time-dependent density functional theory, based on a relativistic energy density functional and including pairing correlations, we analyze the final phase of the process of induced fission of ^{240}Pu, and show that the timescale of neck formation coincides with the assembly of two α-like clusters. Because of its much larger binding energy, the dynamical synthesis of ^{4}He in the neck predominates over other light clusters, e.g., ^{3}H and ^{6}He. At the instant of scission the neck ruptures exactly between the two α-like clusters, which separate because of the Coulomb repulsion and are eventually absorbed by the two emerging fragments. The mechanism of light charged clusters formation at scission could also be linked to ternary fission.

2.
Phys Rev Lett ; 120(2): 022502, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-29376727

RESUMEN

The g factor of the 56 ns half-life isomeric state in ^{128}Cs has been measured using the time-differential perturbed angular distribution method. This state is the bandhead of the positive-parity chiral rotational band, which emerges when an unpaired proton, an unpaired neutron hole, and an even-even core are coupled such that their angular momentum vectors are aplanar (chiral configuration). g-factor measurements can give important information on the relative orientation of the three angular momentum vectors. The measured g factor g=+0.59(1) shows that there is an important contribution of the core rotation in the total angular momentum of the isomeric state. Moreover, a quantitative theoretical analysis supports the conclusion that the three angular momentum vectors lie almost in one plane, which suggests that the chiral configuration in ^{128}Cs demonstrated in previous works by characteristic patterns of electromagnetic transitions appears only above some value of the total nuclear spin.

3.
Braz. j. med. biol. res ; 49(3): e5043, Mar. 2016. graf
Artículo en Inglés | LILACS | ID: lil-771931

RESUMEN

Ovarian cancer is one of the most common causes of death from gynecologic tumors and is an important public health issue. Ghrelin is a recently discovered bioactive peptide that acts as a natural endogenous ligand of the growth hormone secretagogue receptor (GHSR). Several studies have identified the protective effects of ghrelin on the mammalian reproductive system. However, little research has been done on the effects of ghrelin on ovarian cancer cells, and the underlying mechanisms of these effects. We sought to understand the potential involvement of mitogen-activated protein kinases (MAPKs) in ghrelin-mediated inhibition of growth of the ovarian line HO-8910. We applied different concentrations of ghrelin and an inhibitor of the ghrelin receptor (D-Lys3-GHRP-6) to HO-8910 cells and observed the growth rate of cells and changes in phosphorylation of the MAPKs ERK1/2, JNK and p38. We discovered that ghrelin-induced apoptosis of HO-8910 cells was though phosphorylated ERK1/2, and that this phosphorylation (as well as p90rsk phosphorylation) was mediated by the GHSR. The ERK1/2 pathway is known to play an essential part in the ghrelin-mediated apoptosis of HO-8910 cells. Hence, our study suggests that ghrelin inhibits the growth of HO-8910 cells primarily through the GHSR/ERK pathway.


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Regulación Neoplásica de la Expresión Génica/genética , Ghrelina/farmacología , Sistema de Señalización de MAP Quinasas/fisiología , Neoplasias Ováricas/genética , Apoptosis/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Oligopéptidos/metabolismo , Neoplasias Ováricas/metabolismo , Fosforilación/efectos de los fármacos , Receptores de Ghrelina/antagonistas & inhibidores , Receptores de Ghrelina/metabolismo , Células Tumorales Cultivadas
4.
Phys Rev Lett ; 116(3): 032501, 2016 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-26849588

RESUMEN

Isomer shifts have been determined in ^{111-129}Cd by high-resolution laser spectroscopy at CERN-ISOLDE. The corresponding mean square charge-radii changes, from the 1/2^{+} and the 3/2^{+} ground states to the 11/2^{-} isomers, have been found to follow a distinct parabolic dependence as a function of the atomic mass number. Since the isomers have been previously associated with simplicity due to the linear mass dependence of their quadrupole moments, the regularity of the isomer shifts suggests a higher order of symmetry affecting the ground states in addition. A comprehensive description assuming nuclear deformation is found to accurately reproduce the radii differences in conjunction with the known quadrupole moments. This intuitive interpretation is supported by covariant density functional theory.

5.
Braz J Med Biol Res ; 49(3)2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26840702

RESUMEN

Ovarian cancer is one of the most common causes of death from gynecologic tumors and is an important public health issue. Ghrelin is a recently discovered bioactive peptide that acts as a natural endogenous ligand of the growth hormone secretagogue receptor (GHSR). Several studies have identified the protective effects of ghrelin on the mammalian reproductive system. However, little research has been done on the effects of ghrelin on ovarian cancer cells, and the underlying mechanisms of these effects. We sought to understand the potential involvement of mitogen-activated protein kinases (MAPKs) in ghrelin-mediated inhibition of growth of the ovarian line HO-8910. We applied different concentrations of ghrelin and an inhibitor of the ghrelin receptor (D-Lys3-GHRP-6) to HO-8910 cells and observed the growth rate of cells and changes in phosphorylation of the MAPKs ERK1/2, JNK and p38. We discovered that ghrelin-induced apoptosis of HO-8910 cells was though phosphorylated ERK1/2, and that this phosphorylation (as well as p90rsk phosphorylation) was mediated by the GHSR. The ERK1/2 pathway is known to play an essential part in the ghrelin-mediated apoptosis of HO-8910 cells. Hence, our study suggests that ghrelin inhibits the growth of HO-8910 cells primarily through the GHSR/ERK pathway.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/genética , Ghrelina/farmacología , Sistema de Señalización de MAP Quinasas/fisiología , Neoplasias Ováricas/genética , Apoptosis/efectos de los fármacos , Femenino , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Persona de Mediana Edad , Oligopéptidos/metabolismo , Neoplasias Ováricas/metabolismo , Fosforilación/efectos de los fármacos , Receptores de Ghrelina/antagonistas & inhibidores , Receptores de Ghrelina/metabolismo , Células Tumorales Cultivadas
6.
Genet Mol Res ; 14(3): 10553-68, 2015 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-26400287

RESUMEN

Berberine (BBR) is a natural alkaloid with significant anti-tumor activity against many types of cancer cells. In this study, we investigated the molecular mechanisms employed by BBR to repress the proliferation and growth of skin squamous cell carcinoma A431 cells. Berberine was reported to inhibit the proliferation of A431 cells in a dose- and time-dependent manner and was observed to induce a series of biochemical events, including the loss of mitochondrial membrane potential, release of cytochrome-c to cytosol, induction of proteins of the Bcl-2 family and caspases, and the cleavage of poly(ADP)-ribose polymerase. This suggested its ability to induce apoptosis. The results of a wound healing test revealed that berberine inhibited the migration of A431 cells. Ezrin was transfected into A431 cells by RNA interference. The level of expression of Ezrin in the transfected A431 cells was observed to decrease with berberine treatment, which suggested that berberine might inhibit the invasion of A431 cells through Ezrin. The results of this study demonstrated that berberine could potentially inhibit proliferation, induce apoptosis, and inhibit the invasion of A431 cells.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Berberina/farmacología , Proteínas del Citoesqueleto/genética , Células Epiteliales/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Caspasa 3/genética , Caspasa 3/metabolismo , Caspasa 9/genética , Caspasa 9/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Citocromos c/genética , Citocromos c/metabolismo , Proteínas del Citoesqueleto/metabolismo , Relación Dosis-Respuesta a Droga , Células Epiteliales/metabolismo , Células Epiteliales/patología , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Poli(ADP-Ribosa) Polimerasas/genética , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal , Piel/efectos de los fármacos , Piel/metabolismo , Piel/patología , Transgenes , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
7.
Phys Rev Lett ; 115(2): 022501, 2015 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-26207464

RESUMEN

The anomalous rod shape in carbon isotopes has been investigated in the framework of the cranking covariant density functional theory, and two mechanisms to stabilize such a novel shape with respect to the bending motion, extreme spin, and isospin are simultaneously discussed for the first time in a self-consistent and microscopic way. By adding valence neutrons and rotating the system, we have found the mechanism stabilizing the rod shape; i.e., the σ orbitals (parallel to the symmetry axis) of the valence neutrons, important for the rod shape, are lowered by the rotation due to the Coriolis term. The spin and isospin effects enhance the stability of the rod-shaped configuration. This provides a strong hint that a rod shape could be realized in nuclei towards extreme spin and isospin.

8.
Phys Rev Lett ; 113(3): 032501, 2014 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-25083635

RESUMEN

Three sets of chiral doublet band structures have been identified in the ^{103}Rh nucleus. The properties of the observed chiral doublet bands are in good agreement with theoretical results obtained using constrained covariant density functional theory and particle rotor model calculations. Two of them belong to an identical configuration and provide the first experimental evidence for a novel type of multiple chiral doublets, where an "excited" chiral doublet of a configuration is seen together with the "yrast" one. This observation shows that the chiral geometry in nuclei can be robust against the increase of the intrinsic excitation energy.

9.
Scand J Immunol ; 79(1): 51-60, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24219615

RESUMEN

IgA nephropathy (IgAN) diagnosis remains largely based upon immunohistologic detection of IgA- and IgG-containing glomerular deposits in renal mesangial cells, and little is known about the underlying pathogenic mechanisms. This study examines the putative contribution of B cell types, including the Breg type, to IgAN pathogenesis. Twenty-four patients with IgAN and proteinuria (Group A: <3.5 g/24 h, n = 13; Group B: >3.5 g/24 h, n = 11) and 10 healthy controls were enrolled. The frequencies of B cell subtypes in venous blood were measured by flow cytometry. Galactose-deficient IgA1 was measurement by ELISA. Needle biopsies were analysed by histology and immunofluorescence microscopy. Correlation between clinical features and B cell subtypes, including the regulatory B (Breg) cells, and Breg cell-derived immunomodulatory cytokine IL-10 was assessed by Spearman's rank correlation test. IgAN patients had significantly higher frequencies of CD27(+) CD19(+) , CD38(+) CD19(+) , CD86(+) CD19(+) and CD5(+) CD19(+) B cells than the healthy controls, but significantly lower levels of Breg cells and intracellular expression of IL-10 protein in the Breg subtype. Serum IgA concentration positively correlated with CD27(+) CD19(+) B cell frequency and negatively correlated with IL-10(+) Breg cell frequency in IgAN patients, and the percentage of CD19(+) CD5(+) CD1d(+) in CD19(+) cells was negatively correlated with the level of serum Gd-IgA1. Furthermore, the frequencies of CD19(+) CD38(+) and CD19(+) CD86(+) in the CD19(+) subpopulation negatively correlated with the estimated glomerular filtration rate of IgAN patients. Several of the CD19(+) B cell subtypes and the IL-10(+) Breg cells are differentially expressed in IgAN patients and may contribute to the disease pathogenesis.


Asunto(s)
Subgrupos de Linfocitos B/inmunología , Linfocitos B Reguladores/inmunología , Glomerulonefritis por IGA/inmunología , ADP-Ribosil Ciclasa 1/inmunología , ADP-Ribosil Ciclasa 1/metabolismo , Adolescente , Adulto , Anciano , Antígenos CD19/inmunología , Antígenos CD19/metabolismo , Subgrupos de Linfocitos B/metabolismo , Linfocitos B Reguladores/metabolismo , Antígeno B7-2/inmunología , Antígeno B7-2/metabolismo , Femenino , Citometría de Flujo , Galactosa/deficiencia , Glomerulonefritis por IGA/sangre , Glomerulonefritis por IGA/metabolismo , Humanos , Inmunoglobulina A/sangre , Interleucina-10/inmunología , Interleucina-10/metabolismo , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Masculino , Persona de Mediana Edad , Proteinuria/sangre , Proteinuria/inmunología , Proteinuria/metabolismo , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/inmunología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo , Adulto Joven
10.
Phys Rev Lett ; 110(17): 172504, 2013 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-23679714

RESUMEN

Two distinct sets of chiral-partner bands have been identified in the nucleus 133Ce. They constitute a multiple chiral doublet, a phenomenon predicted by relativistic mean field (RMF) calculations and observed experimentally here for the first time. The properties of these chiral bands are in good agreement with results of calculations based on a combination of the constrained triaxial RMF theory and the particle-rotor model.

11.
Phys Rev Lett ; 107(12): 122501, 2011 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-22026766

RESUMEN

Covariant density functional theory and the tilted axis cranking method are used to investigate antimagnetic rotation (AMR) in nuclei for the first time in a fully self-consistent and microscopic way. The experimental spectrum as well as the B(E2) values of the recently observed AMR band in (105)Cd are reproduced very well. This gives a further strong hint that AMR is realized in specific bands in nuclei.

12.
J Int Med Res ; 39(6): 2414-20, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22289561

RESUMEN

This study compared the clinical results of surgical treatment of high complex anal fistula with a conventional seton and a new type of seton consisting of an elastic sheath and alloy core tube for irrigation of the wound track. A total of 438 patients were included in the study; 215 were treated with a conventional seton and 223 with the new-type seton. In patients treated with the new-type seton, the wound track was irrigated daily with 100 ml physiological saline, 100 ml hypertonic saline and 0.5 g metronidazole gel from the second postoperative day until seton removal. The new-type seton was associated with significant reductions in recurrence rate, length of stay and healing time compared with the conventional seton, but there were no significant differences in operation time or postoperative incontinence rates. It is concluded that the new-type seton with irrigating tube can improve the treatment of high complex anal fistula.


Asunto(s)
Fístula Rectal/cirugía , Técnicas de Sutura/instrumentación , Irrigación Terapéutica/instrumentación , Adolescente , Adulto , Incontinencia Fecal/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Técnicas de Sutura/efectos adversos , Irrigación Terapéutica/efectos adversos , Resultado del Tratamiento , Adulto Joven
13.
J Int Med Res ; 38(6): 2053-62, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21227010

RESUMEN

Thymosin-α(1) (TA(1)) has been shown to be effective treatment for chronic hepatitis B virus (HBV) infection. This study investigated the immune response after TA(1) monotherapy in 25 HBV e antigen (HBeAg)-positive patients randomized to receive either 1.6 mg active TA(1) (group A), 1.6 mg recombinant TA(1) (group B) or 3.2 mg recombinant TA(1) (group C) monotherapy for 52 weeks. The percentages of T-helper 1 (T(h)1) cytokine-producing T-cells (interleukin-2 [IL-2], interferon-γ [IFN-γ], tumour necrosis factor-α) and T(h)2 cytokine-producing T-cells (IL-4) were analysed using flow cytometry. In all patients treated with TA(1), cytokine levels and the proportion of peripheral blood mononuclear cells producing these cytokines were significantly increased, compared with baseline and healthy controls. The proportions of each cytokine-producing cell increased gradually over time and were restored to normal levels, and proportions of IFN-γ and IL-4-producing cells reached higher levels than in normal (healthy) controls. The results showed that treatment with TA(1) increased cytokine production, especially IFN-γ, and higher-dose TA(1) exhibited better efficacy against HBV, compared with other treatments studied.


Asunto(s)
Citocinas/biosíntesis , Antígenos e de la Hepatitis B/inmunología , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/inmunología , Células TH1/inmunología , Células Th2/inmunología , Timosina/análogos & derivados , Adulto , Antivirales/farmacología , Antivirales/uso terapéutico , Estudios de Casos y Controles , Demografía , Femenino , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Células TH1/efectos de los fármacos , Células Th2/efectos de los fármacos , Timalfasina , Timosina/farmacología , Timosina/uso terapéutico
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