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1.
Zhonghua Wei Chang Wai Ke Za Zhi ; 26(11): 1075-1081, 2023 Nov 25.
Artículo en Chino | MEDLINE | ID: mdl-37974354

RESUMEN

Obesity has been identified as one of the risk factors for male sexual dysfunction, and it also has a certain impact on fertility. For people with obesity, sexual function is an important aspect of quality of life, but it is often overlooked. Society's stigma against obesity exacerbates the psychological stress of patients with obesity and negatively affects sexual function. Current studies have found that bariatric surgery can reduce body weight and improve sexual function in patients with obesity, and obesity-related gonadal dysfunction is also improved or even subsided after surgery. However, attention needs to be paid to postoperative body mass management and mental health status of patients to prevent postoperative body mass recovery and reversal of sex hormones and sexual function. In addition, there is still controversy about the change in sperm quality after bariatric surgery, and there is a lack of research data on sexual function and sperm parameters and mechanisms after bariatric surgery. Therefore, this article reviews the latest research progress of bariatric surgery and sexual dysfunction, as well as related mechanisms and sperm parameters, to provide a reference for bariatric surgery in patients with obesity with sexual dysfunction.


Asunto(s)
Cirugía Bariátrica , Obesidad Mórbida , Masculino , Humanos , Calidad de Vida , Semen , Obesidad/cirugía , Cirugía Bariátrica/métodos , Hormonas Esteroides Gonadales , Obesidad Mórbida/cirugía
2.
Phys Rev Lett ; 129(13): 132701, 2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36206440

RESUMEN

The ^{13}C(α,n)^{16}O reaction is the main neutron source for the slow-neutron-capture process in asymptotic giant branch stars and for the intermediate process. Direct measurements at astrophysical energies in above-ground laboratories are hindered by the extremely small cross sections and vast cosmic-ray-induced background. We performed the first consistent direct measurement in the range of E_{c.m.}=0.24 to 1.9 MeV using the accelerators at the China Jinping Underground Laboratory and Sichuan University. Our measurement covers almost the entire intermediate process Gamow window in which the large uncertainty of the previous experiments has been reduced from 60% down to 15%, eliminates the large systematic uncertainty in the extrapolation arising from the inconsistency of existing datasets, and provides a more reliable reaction rate for the studies of the slow-neutron-capture and intermediate processes along with the first direct determination of the alpha strength for the near-threshold state.

3.
Zhonghua Wei Chang Wai Ke Za Zhi ; 23(10): 990-995, 2020 Oct 25.
Artículo en Chino | MEDLINE | ID: mdl-33053995

RESUMEN

Objective: To investigate the clinical application of carbon nanoparticles mapping lymph nodes in curative resection for colorectal carcinoma. Methods: Patients diagnosed with colorectal cancer before operation and undergoing radical surgery with intact postoperative pathological data in the Sixth Affiliated Hospital, Sun Yat-sen University from March 2016 to March 2018 were included in this retrospective case-control study. Those who were diagnosed with ileus, recurrent carcinoma or underwent emergency operation were excluded. A total of 1421 cases were included, with 156 cases in the carbon nanoparticles mapping group and 1265 cases in the control group. Using 1∶3 case control matching based on gender, weight, TNM staging and neoadjuvant chemotherapy, 145 and 435 cases were finally recruited in the carbon nanoparticles mapping group and control group, respectively. Patients in the carbon nanoparticles mapping group underwent preoperative colonoscopy with carbon nanoparticles submucosal injection 2.4 (1.0 - 14.0) days before operation. Carbon nanoparticles of 0.25 ml was injected at 4 points (3, 6, 9 and 12 o'clock each) 0.5-1.0 cm around the tumor. The number of eliminated lymph node, number of positive lymph node and positive rate between the two groups were compared, and the number of eliminated lymph node in different subgroups of T stage, N stage, TNM stage and neoadjuvant chemotherapy was analyzed and compared. Results: After case control matching, total number of eliminated lymph nodes in the carbon nanoparticles mapping group was significantly higher than that in the control group (22.2±11.2 vs. 19.0±9.5, t=3.025, P=0.003). However, no statistically significant differences were found in the number of positive lymph node and lymph node positive rate between two groups (all P>0.05). Subgroup analysis showed that as compared to the control group, total number of eliminated lymph nodes in the carbon nanoparticles mapping group was significantly higher in T3 stage subgroup (median: 22 vs. 18, Z=2.435, P=0.015), N0 stage subgroup (median: 20.5 vs. 17.5, Z=2.772, P=0.006), TNM II stage subgroup (median: 23.5 vs. 19.0, Z=2.654, P=0.008) and neoadjuvant chemotherapy (median: 22.5 vs. 13.0, Z=3.287, P=0.001), while compared to the control group, the number of positive lymph node (median: 4.0 vs. 6.5, Z=-2.530, P=0.011) and the lymph node metastasis degree (median: 16% vs. 31%, Z=-2.862, P=0.004) were lower in the carbon nanoparticles mapping group in N2 subgroup. Conclusion: Carbon nanoparticles mapping lymph nodes can effectively enhance the number of eliminated lymph nodes in curative resection for colorectal cancer.


Asunto(s)
Neoplasias Colorrectales , Ganglios Linfáticos/cirugía , Nanopartículas , Materiales Biocompatibles , Carbono , Estudios de Casos y Controles , Neoplasias Colorrectales/cirugía , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Metástasis Linfática , Recurrencia Local de Neoplasia , Estudios Retrospectivos
4.
Sci Rep ; 9(1): 6708, 2019 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-31040356

RESUMEN

The magnetic reversal behavior of a ferromagnet (FM) coupled through an FeMn antiferromagnet (AF) to a pinned ferromagnet has been investigated by polarized neutron reflectivity measurements. With FeMn as the AF layer it is found that there exists 90° interlayer coupling through this layer and that this plays a key role in the transfer of the exchange bias (EB) effect from the FM/AF interface to the AF/pinned-FM interface. Combined with Monte Carlo simulations, we demonstrate that the competition between the interlayer coupling and the anisotropy of the AF layer results in a control of the EB effect which has potential for device applications.

5.
Ultramicroscopy ; 202: 156-162, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31063898

RESUMEN

Magnetic circular dichroism (MCD) and magnetic linear dichroism (MLD) have been investigated in a photoemission electron microscopy (PEEM) system excited by a deep ultra-violet (DUV) laser (with λ = 177.3 nm and hυ = 7.0 eV) for the first time. High resolution PEEM magnetic images (down to 43.2 nm) were directly obtained on a (001)-oriented magnetic FePt film surface with a circularly-polarized light under normal incidence. Furthermore, a stepped Cr seeding layer was applied to induce the formation of large-area epitaxial FePt films with (001) and (111) two orientations, where MLD with large asymmetry was observed in the transition area of two phases. It demonstrates that DUV laser can be a powerful source for high resolution magnetic imaging in the laboratory in absence of synchrotron facilities.

6.
Sci Rep ; 4: 5895, 2014 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-25081387

RESUMEN

The recent discovery of perpendicular magnetic anisotropy (PMA) at the CoFeB/MgO interface has accelerated the development of next generation high-density non-volatile memories by utilizing perpendicular magnetic tunnel junctions (p-MTJs). However, the insufficient interfacial PMA in the typical Ta/CoFeB/MgO system will not only complicate the p-MTJ optimization, but also limit the device density scalability. Moreover, the rapid decreases of PMA in Ta/CoFeB/MgO films with annealing temperature higher than 300°C will make the compatibility with CMOS integrated circuits a big problem. By replacing the Ta buffer layer with a thin Mo film, we have increased the PMA in the Ta/CoFeB/MgO structure by 20%. More importantly, the thermal stability of the perpendicularly magnetized (001)CoFeB/MgO films is greatly increased from 300°C to 425°C, making the Mo/CoFeB/MgO films attractive for a practical p-MTJ application.

7.
Phys Rev Lett ; 110(14): 147207, 2013 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-25167034

RESUMEN

Thin Pt films on an yttrium iron garnet (YIG = Y(3)Fe(5)O(12)) show ferromagneticlike transport properties, which may impact the functionality of Pt in spin current detection, but do not provide direct quantitative information on the Pt magnetization. We report magnetic x-ray magnetic circular dichroism measurements of YIG/Pt(1.5 nm) showing an average Pt moment of 0.054 µ(B) at 300 K and 0.076 µ(B) at 20 K. This observation indicates strong proximity effects and induced magnetic ordering in Pt on magnetic insulators and their contribution to the spin-related measurements should not be neglected. The transport characteristics also suggest considerable modifications in the Pt electronic structure due to magnetic ordering.

8.
Transpl Immunol ; 18(1): 13-21, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17584597

RESUMEN

The interleukin-2 receptor alpha chain (IL-2Ra, CD25) plays a major part in shaping the dynamics of T cell populations following immune activation, due to its role in T cell proliferation and survival. Strategies to blunt the effector responses in transplantation have been developed by devising pharmaceutical agents to block the IL-2 pathways. However, such strategies could adversely affect the CD25(+)FOXP3(+)T regulatory (T reg) populations which also rely on intereukin-2 signaling for survival. The present study shows that a cohort of heart allograft recipients treated with Daclizumab (a humanized anti-CD25 antibody) display FOXP3 expression patterns consistent with functional T regulatory cell populations. High levels of FOXP3 were observed to correlate with lower incidence of and recovery from acute rejection, as well as lower levels of anti-donor HLA antibody production. Therefore, T reg populations appear fully functional in patients treated with Daclizumab, even when 5 doses were administered. By comparison, patients treated with fewer doses or no Daclizumab had a higher incidence of acute rejection, antibody production and graft failure. Therefore, our data indicates that Daclizumab treatment does not interfere with the generation of regulatory T cells and has a beneficial effect on heart allograft survival.


Asunto(s)
Factores de Transcripción Forkhead/análisis , Trasplante de Corazón/inmunología , Subunidad alfa del Receptor de Interleucina-2/antagonistas & inhibidores , Linfocitos T Reguladores/inmunología , Adolescente , Adulto , Anciano , Femenino , Antígenos HLA/inmunología , Humanos , Masculino , Persona de Mediana Edad
9.
Cytotherapy ; 5(5): 349-61, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14578097

RESUMEN

BACKGROUND: Cord blood (CB) has been used as an alternative source of transplantable allogeneic stem cells for a variety of malignant and non-malignant diseases. However, we have demonstrated delayed recovery of T- and B-cell function, and T-cell subsets post unrelated CB transplantation (UCBT), and deficiencies of CB mononuclear cells (MNC) in producing cytokines, including G-CSF, GM-CSF, M-CSF, IL-12, and IL-15. In this study we have investigated the ex vivo generation of DC from CB versus mobilized adult peripheral blood (APB) for later use as adoptive cellular immunotherapy. METHODS: CB and APB-adherent MNC were cultured in serum-free media with GM-CSF IL-4, FLT-3 ligand, tumor growth factor-beta (TGF-beta), and tumor necrosis factor-alpha (TNF-alpha) for 7 days. Morphology, phenotype, immunohistochemistry, clonogenic activity, and alloreactivity in MLR were evaluated. RESULTS: CB and APB monocyte-derived ex vivo expanded DC expressed similar DC markers CD83 (31.27+ 11.7% versus 34.0+ 5.2%, CB versus APB), CD1a (23.4+ 4.2% versus 27.6+ 6.3%), and CD80 (21.97+ 12.01% versus 27.7+ 5.95). Immunohistochemistry showed that cells with DC morphology expressed CDla but not CD14. Neither FLT-3 ligand nor TGF-fl enhanced DC expansion. Addition of 10% autologous plasma to CB cultures promoted greater cell survival and a 150% increase in CDla + /CD80+ cell recovery. CB DC were 62% as effective stimulators of adult allogeneic T-cels as APB DC (p < .05) in allogeneic MLR. DISCUSSION: While phenotypically similar, CB and APB DC have differential potency in allogeneic MLR, which may account for the difference in GvHD and infection incidence and severity between UCBT and allogeneic stem cell transplantation, and may require a different approach for adoptive cellular immunotherapy. The mechanism(s) associated with these differences require further elucidation.


Asunto(s)
Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Células Dendríticas/trasplante , Sangre Fetal/citología , Movilización de Célula Madre Hematopoyética/métodos , Leucocitos Mononucleares/trasplante , Adulto , Antígenos de Superficie/inmunología , Linfocitos B/citología , Linfocitos B/inmunología , Linfocitos B/trasplante , Adhesión Celular/inmunología , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/inmunología , Células Cultivadas , Técnicas de Cultivo/métodos , Citocinas/inmunología , Citocinas/metabolismo , Células Dendríticas/citología , Células Dendríticas/inmunología , Sangre Fetal/inmunología , Sustancias de Crecimiento/farmacología , Humanos , Inmunoterapia/métodos , Recién Nacido , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/inmunología , Recuperación de la Función/inmunología , Linfocitos T/citología , Linfocitos T/inmunología , Linfocitos T/trasplante , Trasplante Homólogo/inmunología
10.
Mol Biol Cell ; 4(11): 1109-19, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8305733

RESUMEN

Anoxia, glucose starvation, calcium ionophore A23187, EDTA, glucosamine, and several other conditions that adversely affect the function of the endoplasmic reticulum (ER) induce the synthesis of the glucose-regulated class of stress proteins (GRPs). The primary GRPs induced by these stresses migrate at 78 and 94 kDa (GRP78 and GRP94). In addition, another protein of approximately 150-170 kDa (GRP170) has been previously observed and is coordinately induced with GRP78 and GRP94. To characterize this novel stress protein, we have prepared an antisera against purified GRP170. Immunofluorescence, Endoglycosidase H sensitivity, and protease resistance of this protein in microsomes indicates that GRP170 is an ER lumenal glycoprotein retained in a pre-Golgi compartment. Immunoprecipitation of GRP170 with our antibody coprecipitates the GRP78 (also referred to as the B cell immunoglobulin-binding protein) and GRP94 members of this stress protein family in Chinese hamster ovary cells under stress conditions. ATP depletion, by immunoprecipitation in the presence of apyrase, does not affect the interaction between GRP78 and GRP170 but results in the coprecipitation of an unidentified 60-kDa protein. In addition, GRP170 is found to be coprecipitated with immunoglobulin (Ig) in four different B cell hybridomas expressing surface IgM, cytoplasmic Ig light chain only, cytoplasmic Ig heavy chain only, or an antigen specific secreted IgG. In addition, in IgM surface expressing WEHI-231 B cells, anti-IgM coprecipitates GRP78, GRP94, as well as GRP170; antibodies against GRP170 and GRP94 reciprocally coprecipitate GRP94/GRP170 as well as GRP78. Results suggest that this 170-kDa GRP is a retained ER lumenal glycoprotein that is constitutively present and that may play a role in immunoglobulin folding and assembly in conjunction or consecutively with GRP78 and GRP94.


Asunto(s)
Retículo Endoplásmico/química , Proteínas HSP70 de Choque Térmico , Proteínas de Choque Térmico/análisis , Inmunoglobulinas/metabolismo , Proteínas de la Membrana/análisis , Adenosina Trifosfato/metabolismo , Animales , Células CHO , Calcimicina/metabolismo , Línea Celular , Cricetinae , Desoxiglucosa/metabolismo , Chaperón BiP del Retículo Endoplásmico , Glucosamina/metabolismo , Glucosa/metabolismo , Proteínas de Choque Térmico/metabolismo , Técnicas Inmunológicas , Membranas Intracelulares/química , Proteínas de la Membrana/metabolismo , Ratones , Microsomas/química , Unión Proteica/fisiología , Tunicamicina/metabolismo
11.
J Cell Physiol ; 154(2): 229-37, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8425905

RESUMEN

Chronic anoxia, glucose starvation, low pH, and numerous other conditions induce the glucose-regulated system of stress proteins (GRPs), whose principal members are observed at 78, 94, and 170 kDa. These stresses may be expected to occur during growth in untreated tumors. To examine the possibility that GRPs are correspondingly induced, we have examined the protein profiles of small (< 0.1 g), intermediate (0.2-0.8 g), and large (> 1.8 g) radiation-induced fibrosarcoma (RIF) tumors grown on C3H mice. One and two-dimensional gel electrophoresis indicate that the principal GRPs at 78 and 94 are coordinately and substantially increased in large tumor masses, relative to the small, and may be partially increased in the intermediate tumors. Necrotic material removed from large tumors exhibited an identical pattern of GRP induction with no visible indication of protein degradation and also contained a significant fraction of viable cells. Western blot analysis using rabbit antisera raised against the 78 and 170 kDa GRPs also demonstrated the enhanced accumulation of these proteins in the large tumors. The antibody against the 170 kDa GRP was also capable of detecting the induction of this stress protein in large tumors by indirect immunofluorescence analysis. Northern blot studies using a probe for the GRP 78 gene also showed an increase in GRP 78 message in large tumors as well as in RIF cells exposed to anoxic stress in vitro. Two-dimensional gel electrophoresis indicated that the major heat shock proteins at 70 and 90 kDa were not increased in the larger tumors, and the amount of the 90 kDa species was reduced. Finally, the quantity of vimentin and its degradation products is significantly diminished in large tumors and in anoxic cells. This study demonstrates that RIF tumor cells undergo a glucose regulated stress response in situ during tumor growth.


Asunto(s)
Fibrosarcoma/metabolismo , Proteínas HSP70 de Choque Térmico , Proteínas de la Membrana/metabolismo , Neoplasias Inducidas por Radiación/metabolismo , Sarcoma Experimental/metabolismo , Animales , Northern Blotting , División Celular , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Ratones , Ratones Endogámicos C3H
12.
FEBS Lett ; 288(1-2): 229-32, 1991 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-1879557

RESUMEN

Subconfluent, log-phase Chinese hamster ovary cells induced the major heat-shock proteins (hsp) when cells were refed, 40 hours after seeding. This method of inducing heat-shock proteins was also obtained by refeeding with fresh serum-free media, but not with media with a long shelf life or with media prepared without glutamine. It was observed that addition of glutamine alone to cultures at 40 hours post-seeding induced heat-shock proteins. Addition of ammonium chloride, however, had no discernible effect on heat-shock protein synthesis. Northern blot analysis indicated that this phenomenon reflected an increase in the levels of message for the constitutive/inducible member of the hsp 70 family, but not the non-constitutive member. To determine the effect of this induction on heat sensitivity, unfed and 'heat-shock-induced' refed cultures were heated at 45 degrees C. No significant difference in cell survival was observed. Therefore glutamine is the necessary ingredient required for the induction of heat-shock proteins and this method of inducing heat-shock proteins does not alter heat sensitivity.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Glutamina/farmacología , Proteínas de Choque Térmico/biosíntesis , Cloruro de Amonio/farmacología , Animales , Northern Blotting , Línea Celular , Electroforesis en Gel de Poliacrilamida , Proteínas de Choque Térmico/genética , Cinética , Temperatura
13.
Exp Cell Res ; 182(1): 105-13, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2714397

RESUMEN

Madin-Darby canine kidney (MDCK) cells spontaneously form dome-like structures in vitro, a phenomenon which has been proposed to be indicative of cellular differentiation. This study indicates the existence of a correlation between the induction of domes and of glucose-regulated proteins during glucose starvation. When MDCK monolayers were glucose deprived, domes appeared very rapidly. After only 3 h of glucose deprivation domes appeared in 69% of the microscope fields. The level of expression of glucose-regulated proteins (grps) as well as domes was examined over a 6-h time interval of glucose deprivation. Both grp 76 and 97 were induced over this time interval, with grp 76 being the more readily detectable. The level of induction of grp 76 as a function of time was quantitated by means of densitometry measurements. The induction of domes was examined in parallel with the induction of grp 76. The results indicated that the induction of grp 76 and domes occurs with a similar time course. The effect of glucose deprivation on the initial rate of ouabain-sensitive Rb+ uptake was also examined. Within the first 4 h of glucose deprivation, the initial rate of ouabain-sensitive Rb+ uptake did not differ significantly in glucose-deprived and control MDCK monolayers. These observations indicate that unlike the case with other methods of dome induction (e.g., treatment with either prostaglandin E1 (PGE1) or hexamethylene bis-acetamide (HMBA] glucose deprivation does not affect the Na+K+ ATPase activity of MDCK monolayers. These observations suggest that PGE1, HMBA, and glucose deprivation affect dome formation in MDCK monolayers by means of distinct mechanisms.


Asunto(s)
Glucosa/fisiología , Proteínas HSP70 de Choque Térmico , Proteínas de la Membrana/biosíntesis , Acetamidas/farmacología , Alprostadil/farmacología , Animales , Transporte Biológico , Diferenciación Celular , Línea Celular , Medios de Cultivo , Perros , Células Epiteliales , Riñón/citología , Peso Molecular , Ouabaína/farmacología , Rubidio/metabolismo
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