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1.
J Phys Condens Matter ; 36(32)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38657633

RESUMEN

We experimentally investigate the charge-spin interconversion by introducing a lighter impurity, namely nitrogen (N) into Pt by varying the nitrogen gas flow rate,Qfrom 0 to 20%, and studying the Onsager reciprocity of spin Hall effect (SHE) via complementary methods of spin-torque ferromagnetic resonance and spin-pumping inverse SHE measurements, respectively. We notice a reduction in the crystalline nature of Pt upon nitrogen incorporation. We observe the influence of extrinsic side-jump scattering induced SHE by measuring the spin Hall efficiency,θSHin a wide temperature range from 10 to 296 K. This work establishes the incorporation of N in Pt by using sputtering, to enhance the SHE via extrinsic scattering as well as to observe the reciprocal effects of charge-spin interconversion.

3.
J Obstet Gynaecol Res ; 49(9): 2370-2378, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37365774

RESUMEN

AIM: Minimally invasive surgery (MIS) has been introduced as an alternative to more radical surgical procedures. The Japan Society of Gynecologic and Obstetric Endoscopy and Minimally Invasive Therapy conducted a cross-sectional questionnaire survey to ascertain the status of MIS for endometrial cancer. METHODS: The survey was conducted between May 10 and June 30, 2022. The questionnaire included information on personal attributes, academic affiliations, qualifications, hysterectomies, and intraoperative procedures performed. RESULTS: The total number of questionnaire respondents was 436 (9.2% of the membership). The hysterectomy methods and percentage performed were as follows: simple total hysterectomy (equivalent to benign surgery), 3%; simple total hysterectomy with care to avoid shaving the cervix, 31%; extended total hysterectomy, 48%; and modified radical hysterectomy, 15%. An analysis of hysterectomies performed using MIS for endometrial cancer by qualified gynecologists of endoscopy or board-certified gynecologic oncologists showed a tendency not to choose simple total hysterectomy compared to the gynecologists who did not hold certification (p = 0.019, p = 0.045, and p = 0.010, respectively). Additionally, 67% of respondents did not use uterine manipulators, and 59% of the respondents did not perform lymph node dissection following the guidelines for treating endometrial cancer in Japan. CONCLUSION: This study provided the current status of MIS for endometrial cancer in Japan. The hysterectomy method, use of uterine manipulators, and criteria for omitting lymph node dissection were generally in agreement with the guidelines. Currently, an extra-fascial simple hysterectomy, including at least not shaving the cervix, was a major method for early invasive endometrial cancer using MIS.


Asunto(s)
Neoplasias Endometriales , Laparoscopía , Femenino , Humanos , Estudios Transversales , Japón , Neoplasias Endometriales/cirugía , Neoplasias Endometriales/patología , Histerectomía/métodos , Encuestas y Cuestionarios , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Estudios Retrospectivos , Laparoscopía/métodos
4.
Acc Chem Res ; 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34339603

RESUMEN

ConspectusIn this Account, we describe the challenges and promising applications of transmission electron microscopy (TEM) imaging and spectroscopy at cryogenic temperatures. Our work focuses on two areas of application: the delay of electron-beam-induced degradation and following low-temperature phenomena in a continuous and variable temperature range. For the former, we present a study of LiMn1.5Ni0.5O4 lithium ion battery cathode material that undergoes electron beam-induced degradation when studied at room temperature by TEM. Cryogenic imaging reveals the true structure of LiMn1.5Ni0.5O4 nanoparticles in their discharged state. Improved stability under electron beam irradiation was confirmed by following the evolution of the O K-edge fine structure by electron energy-loss spectroscopy. Our results demonstrate that the effect of radiation damage on discharged LiMn1.5Ni0.5O4 was previously underestimated and that atomic-resolution imaging at cryogenic temperature has a potential to be generalized to most of the Li-based materials and beyond. For the latter, we present two studies in the imaging of low-temperature phenomena on the local scale, namely, the evolution of ferroelectric and ferromagnetic domains walls, in BaTiO3 and Y3Fe5O12 systems, respectively, in a continuous and variable temperature range. Continuous imaging of the phase transition in BaTiO3, a prototypical ferroelectric system, from the low-temperature orthorhombic phase continuously up to the centrosymmetric high-temperature phase is shown to be possible inside a TEM. Similarly, the propagation of domain walls in Y3Fe5O12, a magnetic insulator, is studied from ∼120 to ∼400 K and combined with the application of a magnetic field and electrical current pulses to mimic the operando conditions as in domain wall memory and logic devices for information technology. Such studies are promising for studying the pinning of the ferroelectric and magnetic domains versus temperature, spin-polarized current, and externally applied magnetic field to better manipulate the domain walls. The capability of combining operando TEM stimuli such as current, voltage, and/or magnetic field with in situ TEM imaging in a continuous cryogenic temperature range will allow the uncovering of fundamental phenomena on the nanometer scale. These studies were made possible using a MEMS-based TEM holder that allowed an electron-transparent sample to be transferred and electrically contacted on a MEMS chip. The six-contact double-tilt holder allows the alignment of the specimen into its zone axis while simultaneously using four electrical contacts to regulate the temperature and two contacts to apply the electrical stimuli, i.e., operando TEM imaging. This Account leads to the demonstration of (i) the high-resolution imaging and spectroscopy of nanoparticles oriented in the desired [110] zone-axis direction at cryogenic temperatures to mitigate the electron beam degradation, (ii) imaging of low-temperature transitions with accurate and continuous control of the temperature that allowed single-frame observation of the presence of both the orthorhombic and tetragonal phases in the BaTiO3 system, and (iii) magnetic domain wall propagation as a function of temperature, magnetic field, and current pulses (100 ns with a 100 kHz repetition rate) in the Y3Fe5O12 system.

5.
ACS Appl Mater Interfaces ; 12(37): 41802-41809, 2020 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-32819087

RESUMEN

The atomically flat interface of the Y3Fe5O12 (YIG) thin film and the Gd3Ga5O12 (GGG) substrate plays a vital role in obtaining the magnetization dynamics of YIG below and above the anisotropy field. Here, magnetoimpedance (MI) is used to investigate the magnetization dynamics in fully epitaxial 45 nm YIG thin films grown on the GGG (001) substrates using a copper strip coil in the MHz-GHz frequency region. The resistance (R) and reactance (X), which are components of impedance (Z), allow us to probe the absorptive and dispersive components of the dynamic permeability, whereas a conventional spectrometer only measures the field derivative of the power absorbed. The distinct excitation modes arising from the resonance in the uniform and dragged magnetization states of YIG are respectively observed above and below the anisotropy field. The magnetodynamics clearly shows the visible dichotomy between two resonant fields below and above the anisotropy field and its motion as a function of the direction of the applied magnetic field. A low value of a damping factor of ∼4.7 - 6.1 × 10-4 is estimated for uniform excitation mode with an anisotropy field of 65 ± 2 Oe. Investigation of below and above anisotropy field-dependent magnetodynamics in the low-frequency mode can be useful in designing the YIG-based resonators, oscillators, filters, and magnonic devices.

6.
Biochem Biophys Res Commun ; 521(4): 821-826, 2020 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-31706576

RESUMEN

Lanternfish, a family Myctophidae, use ventro-lateral body photophores for camouflage of the ventral silhouette, a strategy called counterillumination. While other deep-sea fishes possess pigmented filters and silver reflectors to match sunlight filtering down through the depths, myctophids developed a blue-green reflector for this purpose. In this study, we showed in a lanternfish Diaphus watasei that the reflector comprised monolayered iridophores containing multilayered guanine crystals which enable high reflection with light interference colouration. Platelets shape in body photophores is an unique near-regular hexagonal, probably to allow the homogeneity of reflection angle of the luminescence from photocytes. Focus point of the parabola-like reflector is positioned on the photocytes that ensures the light produced from the photocytes is redirected to the ventral direction. In vitro luminescence reaction using purified luciferase and the substrate coelenterazine showed the light emission at λmax 454 nm, while reflection spectra of the iridophores exhibit peaks at longer wavelength, which accomplish to alter the luminescence emitted from photocytes to longer wavelength to fit the mesopelagic light environment. Taken together, we revealed multiple mechanistic elaborations in myctophid body photophores to achieve effective control of biochemical luminescence for counterillumination.


Asunto(s)
Peces/fisiología , Animales , Mimetismo Biológico/fisiología , Plaquetas/química , Plaquetas/fisiología , Peces/anatomía & histología , Guanina/química , Imidazoles/metabolismo , Luciferasas/metabolismo , Luminiscencia , Pirazinas/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
7.
Sci Rep ; 8(1): 16940, 2018 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-30451930

RESUMEN

Recently, structural colour formation and light control by accumulated guanine crystals were reported. However, the relationship between light interference by guanine platelets and light intensity in an individual platelet must be examined further. This study presents experimental evidence that the guanine crystal platelets of fishes aid in efficiently controlling the enhancement of light intensity based on light interference between platelets floating in a micro-space. In addition, a magnetic orientation technique enabled us to dynamically modulate the arrangement of platelets floating in water. A group orientation of the platelets under magnetic fields exhibited a distinct enhancement of the light interference between platelets present in the micro-space, and a two-fold enhancement of the reflected light intensity was achieved by comparing two arrangements of magnetically oriented platelets. The developed micro-optic light control method employing tiny platelets floating under aqueous liquid conditions is expected to facilitate the creation of tuneable optical micro-devices, e.g., a micro-'search-light' for individual cell analysis.


Asunto(s)
Guanina/química , Campos Magnéticos , Fotones , Animales , Cristalización , Carpa Dorada , Óptica y Fotónica
8.
Acta Obstet Gynecol Scand ; 96(9): 1128-1135, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28597474

RESUMEN

INTRODUCTION: Although endometriosis is a benign disease, it shares some features with cancers, such as invasiveness and the potential to metastasize. This study sought to investigate the epithelial-mesenchymal transition status in human endometriotic lesions. MATERIAL AND METHODS: Thirteen endometriosis patients and 10 control women without endometriosis undergoing surgery for benign indications were recruited. We examined the expression of E-cadherin, vimentin, and epithelial-mesenchymal transition-induced transcriptional factors, such as Snail and ZEB1, by immunohistochemistry. We evaluated the expression of each marker in epithelial cells of both endometriotic lesions (ovarian endometrioma, deep infiltrating endometriosis, adenomyosis) and normal endometria. The correlation between ZEB1 expression and serum level of CA125 was also investigated. RESULTS: Immunohistochemical analysis revealed that although E-cadherin, vimentin, and Snail were expressed in epithelia of normal endometria and endometriotic lesions, ZEB1 expression was only expressed in epithelia of endometriotic lesions. Additionally, ZEB1 was most frequently observed in epithelial cells of invasive endometriosis. The endometriosis patients with high serum CA125 level were more likely to have ZEB1-positive lesions. CONCLUSIONS: This is the first observation of ZEB1 expression in epithelial cells of benign disease. The preferential expression of ZEB1 in epithelial cells of endometriotic lesions suggests that these cells may have, at least in part, a higher level of mesenchymal features possibly via ZEB1-driven epithelial-mesenchymal transition than normal endometria and that ZEB1 can be a potential indicator of invasiveness or severity of endometriosis.


Asunto(s)
Biomarcadores/metabolismo , Endometriosis/diagnóstico , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo , Adenomiosis/diagnóstico , Adenomiosis/metabolismo , Adenomiosis/patología , Adenomiosis/cirugía , Adulto , Endometriosis/metabolismo , Endometriosis/patología , Endometriosis/cirugía , Femenino , Humanos , Inmunohistoquímica , Ligamentos/patología , Invasividad Neoplásica , Enfermedades del Ovario/diagnóstico , Enfermedades del Ovario/metabolismo , Enfermedades del Ovario/patología , Enfermedades del Ovario/cirugía , Valor Predictivo de las Pruebas , Adulto Joven
9.
Endocr J ; 63(1): 9-20, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26536897

RESUMEN

Oxidative stress has a bidirectional role in the development and maturation of zygotes and embryos. Reduction-oxidation reactions and regulatory proteins, such as thioredoxin (TRX) and thioredoxin reductase (TRXR), are intimately involved in the regulation of oxidative stress. The aim of this study was to determine the levels of TRX mRNA and protein in ovarian follicles collected from women undergoing in vitro fertilization (IVF) and to assess these levels relative to follicle size, presence of oocytes, and responsiveness to superovulation. Follicular fluid (FF) and/or granulosa cells (GCs) from large and small follicles were collected at the time of ovum pick-up from 42 IVF patients enrolled in this study. We divided the patients into normal and poor responders (NR and PR, respectively) based on the serum estradiol levels on the day of human chorionic gonadotropin (hCG) administration. We also compared the TRX concentration in FF (FF-TRX) between oocyte-containing follicles (Oc+) and empty follicles (Oc-). The transcript levels of TRX, but not TRXR, were significantly higher in GCs derived from follicles collected from NR than PR, as determined by semi-quantitative RT-PCR analysis. In NR, the FF-TRX was significantly higher in Oc+ follicles than in Oc- follicles and also in large Oc+ follicles than in large Oc- follicles. Unlike NR, PR exhibited no positive association with elevated FF-TRX and presence of oocytes. Based on its collective anti-oxidative, cytoprotective, and cytokine-like properties of TRX, TRX is likely to be involved in the optimal growth and maturation of ovarian follicles and responsiveness to hyperstimulation.


Asunto(s)
Fertilización In Vitro , Folículo Ovárico/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Adulto , Antioxidantes/metabolismo , Estudios de Casos y Controles , Femenino , Líquido Folicular/metabolismo , Células de la Granulosa/metabolismo , Humanos , Infertilidad/genética , Infertilidad/metabolismo , Infertilidad/terapia , Inducción de la Ovulación , Oxidación-Reducción , Embarazo
10.
Biol Reprod ; 93(2): 37, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26108791

RESUMEN

Repeated and dramatic pregnancy-induced uterine enlargement and remodeling throughout reproductive life suggests the existence of uterine smooth muscle stem/progenitor cells. The aim of this study was to isolate and characterize stem/progenitor-like cells from human myometrium through identification of specific surface markers. We here identify CD49f and CD34 as markers to permit selection of the stem/progenitor cell-like population from human myometrium and show that human CD45(-) CD31(-) glycophorin A(-) and CD49f(+) CD34(+) myometrial cells exhibit stem cell-like properties. These include side population phenotypes, an undifferentiated status, high colony-forming ability, multilineage differentiation into smooth muscle cells, osteoblasts, adipocytes, and chondrocytes, and in vivo myometrial tissue reconstitution following xenotransplantation. Furthermore, CD45(-) CD31(-) glycophorin A(-) and CD49f(+) CD34(+) myometrial cells proliferate under hypoxic conditions in vitro and, compared with the untreated nonpregnant myometrium, show greater expansion in the estrogen-treated nonpregnant myometrium and further in the pregnant myometrium in mice upon xenotransplantation. These results suggest that the newly identified myometrial stem/progenitor-like cells influenced by hypoxia and sex steroids may participate in pregnancy-induced uterine enlargement and remodeling, providing novel insights into human myometrial physiology.


Asunto(s)
Antígenos CD34/genética , Antígenos CD34/fisiología , Integrina alfa6/genética , Integrina alfa6/fisiología , Miometrio/metabolismo , Células Madre/fisiología , Útero/fisiología , Animales , Diferenciación Celular , Hipoxia de la Célula , Linaje de la Célula/genética , Femenino , Glicoforinas/biosíntesis , Glicoforinas/genética , Células Madre Hematopoyéticas , Humanos , Ratones , Miometrio/citología , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/biosíntesis , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/genética , Embarazo
11.
Endocr J ; 60(10): 1155-64, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23883529

RESUMEN

Nerve growth factor (NGF) has been recently proposed as one of the key factors responsible not only for promotion of nerve fiber growth but also for the onset and maintenance of pain in a variety of diseases. The aim of this study was to investigate the role of NGF in the pelvic pain associated with endometriosis. Tissue and peritoneal fluid samples were collected from 95 women with laparoscopically and histopathologically confirmed endometriosis and 59 control women without endometriosis. Expression levels of NGF mRNA and protein were examined using real-time RT-PCR and immunohistochemistry, respectively. Concentration of NGF in the peritoneal fluid (PF-NGF) was measured using ELISA. The degree of dyspareunia and dysmenorrhea was evaluated using a verbal rating scale. Real-time RT-PCR analysis revealed that NGF mRNA was significantly more abundant in the ovarian endometriomas and peritoneal endometriosis than in the normal control endometrium. Immunohistochemical analyses demonstrated that NGF was prominently expressed and preferentially localized to the glands of the ovarian endometriomas and peritoneal endometriosis, whereas it was only weakly detectable in the normal endometrium. Although PF-NGF was undetectable in some normal subjects and endometriosis patients, elevated PF-NGF in the peritoneal fluid was more frequently observed in endometriosis patients with severe pain than in those with less severe pain. Our results suggest that NGF produced locally in the peritoneal cavity may be involved in the generation of endometriosis-associated pelvic pain.


Asunto(s)
Dismenorrea/etiología , Dispareunia/etiología , Endometriosis/complicaciones , Factor de Crecimiento Nervioso/fisiología , Dolor Pélvico/etiología , Adulto , Líquido Ascítico/química , Endometriosis/fisiopatología , Femenino , Humanos , Factor de Crecimiento Nervioso/biosíntesis , Regulación hacia Arriba
12.
J Obstet Gynaecol Res ; 39(3): 692-700, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23107338

RESUMEN

AIM: The purpose of this study was to assess the relationship between chronically impaired spermatogenesis induced by exposing mice to doxorubicin (DXR) and expression of the infertility factor c-kit. METHOD: Eight-week-old male Institute for Cancer Research (ICR) mice were intraperitoneally treated with DXR (0.15 mg/kg, DXR group) or saline (0.15 mg/kg, control group) twice weekly for five weeks and were killed 14 weeks after initial exposure. The animals were sacrificed and bilateral testes were removed and weighed. The testes were stored for the mRNA assay and were fixed for immunohistochemistry. Some testicular samples were fixed in 10% formalin for histopathological examination. RESULTS: Testicular weight (67.6 ± 9.7 mg, P < 0.05), sperm motility (18 ± 6.0%, P < 0.05) and the fertilization rate (2-to-16-cell embryos, 5%; P < 0.05) were significantly lower in the DXR group than in the control group. In the DXR group there was severe tissue damage from the spermatogonia onward, and the Sertoli cell ratio was lower in the DXR group than in the control group (38% vs. 9%, P < 0.05). In addition, there was a decrease in c-kit protein expression, and the amount of c-kit messenger ribonucleic acid (mRNA) expression according to a semiquantitative method was also decreased. CONCLUSION: Expression of c-kit in the mice with chronically impaired spermatogenesis induced by long-term, low-dose administration of DXR correlated with the decrease in the number of spermatogonia.


Asunto(s)
Infertilidad Masculina/inducido químicamente , Proteínas Proto-Oncogénicas c-kit/metabolismo , Espermatogénesis , Espermatogonias/metabolismo , Animales , Antibióticos Antineoplásicos , Modelos Animales de Enfermedad , Doxorrubicina , Fertilización In Vitro , Inmunohistoquímica , Infertilidad Masculina/metabolismo , Infertilidad Masculina/patología , Masculino , Ratones , Tamaño de los Órganos , ARN Mensajero/metabolismo , Análisis de Semen , Testículo/patología
13.
Magn Reson Med Sci ; 11(4): 283-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23269015

RESUMEN

PURPOSE: To demonstrate the reduction in vascular bed volume (VBV) of uterine fibroids after administration of gonadotropin-releasing hormone analogue (GnRHa) using magnetic resonance (MR) imaging including dynamic double-echo R2* imaging (DDE-R2*I) and to assess the value of DDE-R2*I as a predictor of such reduction. METHODS: Twenty-one women with uterine intramural fibroids underwent MR imaging including DDE-R2*I before GnRHa treatment. DDE-R2*I was acquired using a single-section, double-echo, fast spoiled gradient recalled acquisition in the steady state (SPGR) sequence. We calculated the area under the curve (AUC) of the signal intensity on R2*I within a 3×3-cm²region of interest that served to represent the VBV. We repeated MR imaging after 2 administrations of GnRHa and repeated image analyses. We statistically analyzed correlations between (A) pre-treatment AUC (AUC(pre)) and AUC reduction and (B) AUC(pre) and volume reduction. RESULTS: The interval between the 2 MR studies ranged from 56 to 119 days (mean: 80.4 days). The average volume of the fibroids before GnRHa treatment was 647.8 mL compared with 463.4 mL after the therapy (decreased by an average of 28.5%; P<0.0001). Meanwhile, measured AUC was reduced by 55.3% (483.4 vs. 206.5; P<0.0001). AUC(pre) correlated with volume reduction (r=0.68), but not AUC reduction. CONCLUSIONS: We confirmed reduction in the VBV of fibroids using DDE-R2*I. The measurement of AUC(pre) on DDE-R2*I aids prediction of fibroid volume reduction but correlates poorly with the percentage of AUC reduction.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Leiomioma/irrigación sanguínea , Leiomioma/tratamiento farmacológico , Imagen por Resonancia Magnética/métodos , Neoplasias Uterinas/irrigación sanguínea , Neoplasias Uterinas/tratamiento farmacológico , Adulto , Área Bajo la Curva , Medios de Contraste , Femenino , Estudios de Seguimiento , Gadolinio DTPA , Hormona Liberadora de Gonadotropina/uso terapéutico , Humanos , Aumento de la Imagen/métodos , Resultado del Tratamiento , Útero/patología , Adulto Joven
14.
J Minim Invasive Gynecol ; 18(1): 135-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21195970

RESUMEN

We present 2 case reports of anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis that was successfully treated via laparoscopic ovarian cystectomy. In both cases, resection of an ovarian teratoma resulted in eventual full recovery. Although adnexectomy has been reported for tumor resection in anti-NMDAR encephalitis, we chose ovarian cystectomy to preserve ovarian function. The efficacy of cystectomy is equivalent to that of adnexectomy. This suggests that ovarian adnexectomy may not be necessary in anti-NMDAR encephalitis with ovarian teratoma.


Asunto(s)
Autoanticuerpos , Encefalitis/inmunología , Neoplasias Ováricas/cirugía , Receptores de N-Metil-D-Aspartato/inmunología , Teratoma/cirugía , Adulto , Femenino , Humanos , Laparoscopía , Neoplasias Ováricas/complicaciones , Teratoma/complicaciones
15.
Circ Res ; 106(10): 1613-23, 2010 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-20508201

RESUMEN

RATIONALE: Amniotic membrane is known to have the ability to transdifferentiate into multiple organs and is expected to stimulate a reduced immunologic reaction. OBJECTIVE: Determine whether human amniotic membrane-derived mesenchymal cells (hAMCs) can be an ideal allograftable stem cell source for cardiac regenerative medicine. METHODS AND RESULTS: We established hAMCs. After cardiomyogenic induction in vitro, hAMCs beat spontaneously, and the calculated cardiomyogenic transdifferentiation efficiency was 33%. Transplantation of hAMCs 2 weeks after myocardial infarction improved impaired left ventricular fractional shortening measured by echocardiogram (34+/-2% [n=8] to 39+/-2% [n=11]; P<0.05) and decreased myocardial fibrosis area (18+/-1% [n=9] to 13+/-1% [n=10]; P<0.05), significantly. Furthermore hAMCs transplanted into the infarcted myocardium of Wistar rats were transdifferentiated into cardiomyocytes in situ and survived for more than 4 weeks after the transplantation without using any immunosuppressant. Immunologic tolerance was caused by the hAMC-derived HLA-G expression, lack of MHC expression of hAMCs, and activation of FOXP3-positive regulatory T cells. Administration of IL-10 or progesterone, which is known to play an important role in feto-maternal tolerance during pregnancy, markedly increased HLA-G expression in hAMCs in vitro and, surprisingly, also increased cardiomyogenic transdifferentiation efficiency in vitro and in vivo. CONCLUSIONS: Because hAMCs have a high ability to transdifferentiate into cardiomyocytes and to acquire immunologic tolerance in vivo, they can be a promising cellular source for allograftable stem cells for cardiac regenerative medicine.


Asunto(s)
Amnios/citología , Amnios/fisiología , Trasplante de Células Madre Mesenquimatosas/métodos , Miocitos Cardíacos/citología , Trasplante Heterólogo/fisiología , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/fisiología , Diferenciación Celular , Parto Obstétrico , Ecocardiografía , Femenino , Rechazo de Injerto/prevención & control , Corazón/fisiología , Humanos , Recién Nacido , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Ratones , Miocitos Cardíacos/fisiología , Embarazo , Ratas , Ratas Wistar , Tolerancia al Trasplante , Función Ventricular Izquierda/fisiología
16.
PLoS One ; 5(4): e10387, 2010 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-20442847

RESUMEN

BACKGROUND: The human endometrium undergoes cyclical regeneration throughout a woman's reproductive life. Ectopic implantation of endometrial cells through retrograde menstruation gives rise to endometriotic lesions which affect approximately 10% of reproductive-aged women. The high regenerative capacity of the human endometrium at eutopic and ectopic sites suggests the existence of stem/progenitor cells and a unique angiogenic system. The objective of this study was to isolate and characterize putative endometrial stem/progenitor cells and to address how they might be involved in the physiology of endometrium. METHODOLOGY/PRINCIPAL FINDINGS: We found that approximately 2% of the total cells obtained from human endometrium displayed a side population (SP) phenotype, as determined by flow cytometric analysis of Hoechst-stained cells. The endometrial SP (ESP) cells exhibited preferential expression of several endothelial cell markers compared to endometrial main population (EMP) cells. A medium specific for endothelial cell culture enabled ESP cells to proliferate and differentiate into various types of endometrial cells, including glandular epithelial, stromal and endothelial cells in vitro, whereas in the same medium, EMP cells differentiated only into stromal cells. Furthermore, ESP cells, but not EMP cells, reconstituted organized endometrial tissue with well-delineated glandular structures when transplanted under the kidney capsule of severely immunodeficient mice. Notably, ESP cells generated endothelial cells that migrated into the mouse kidney parenchyma and formed mature blood vessels. This potential for in vivo angiogenesis and endometrial cell regeneration was more prominent in the ESP fraction than in the EMP fraction, as the latter mainly gave rise to stromal cells in vivo. CONCLUSIONS/SIGNIFICANCE: These results indicate that putative endometrial stem cells are highly enriched in the ESP cells. These unique characteristics suggest that ESP cells might drive physiological endometrial regeneration and be involved in the pathogenesis of endometriosis.


Asunto(s)
Endometrio/citología , Neovascularización Fisiológica , Regeneración , Células Madre/citología , Animales , Vasos Sanguíneos/citología , Vasos Sanguíneos/crecimiento & desarrollo , Diferenciación Celular , Proliferación Celular , Trasplante de Células , Células Cultivadas , Endometrio/fisiología , Femenino , Riñón , Ratones , Ratones SCID
17.
Dalton Trans ; 39(4): 1113-7, 2010 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-20066199

RESUMEN

Polycrystalline clathrate samples of nominal K(8)Ga(x)Sn(46-x) were prepared by the spark plasma sintering method to investigate their crystal structures, mobilities and thermoelectric properties. The samples almost had a single-phase type-I clathrate structure, and their relative densities reached as high as 98%. The room-temperature mobility of the K(8)Ga(8)Sn(38) sample was 25 cm(2) V(-1) s(-1), which substantially exceeded the reported mobilities of Rb- and Cs-containing Sn clathrates. Moreover, the mobility was larger than those of the type-I Ba(8)Ga(16)Sn(30), which had more Ga substituting atoms in unit cell. A higher mobility might accordingly be achieved in thermoelectric clathrates with a smaller number of substituting atoms. Their electrical conductivities and Seebeck coefficients in the temperature range 300-450 K were typical of n-type doped semiconductors in the extrinsic region while their room-temperature lattice thermal conductivities were as low as approximately 11 mW cm(-1) K(-1). The maximum dimensionless figure of merit ZT was estimated to be 0.27 at 490 K from the Seebeck coefficient of -262 microV K(-1) and the electrical conductivity of 96 S cm(-1) for the K(8)Ga(8)Sn(38) sample with a carrier concentration of 2.9 x 10(19) cm(-3).

18.
Fertil Steril ; 92(4): 1240-1242, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19501819

RESUMEN

A cross-sectional comparative study among women who underwent surgical treatment for endometriosis revealed that frequency of the Ala/Ala genotype at aryl hydrocarbon receptor repressor (AHRR) Pro185Ala polymorphism was three times higher (27.6% vs. 9.9%) in the younger group (30 years). AHHR genotyping may help to identify a subpopulation of women who are susceptible to the earlier onset of endometriosis.


Asunto(s)
Endometriosis/epidemiología , Endometriosis/genética , Proteínas Represoras/genética , Enfermedades Uterinas/epidemiología , Enfermedades Uterinas/genética , Adulto , Factores de Edad , Edad de Inicio , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Endometriosis/diagnóstico , Endometriosis/cirugía , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Genotipo , Humanos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Enfermedades Uterinas/diagnóstico , Enfermedades Uterinas/cirugía , Adulto Joven
19.
J Immunol ; 182(11): 7074-84, 2009 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-19454705

RESUMEN

Innate mucosal immune responses, including recognition of pathogen-associated molecular patterns through Toll-like receptors, play an important role in preventing infection in the female reproductive tract (FRT). Damaged cells release nucleotides, including ATP and uridine 5'-diphosphoglucose (UDP-glucose), during inflammation and mechanical stress. We show in this report that P2RY14, a membrane receptor for UDP-glucose, is exclusively expressed in the epithelium, but not the stroma, of the FRT in humans and mice. P2RY14 and several proinflammatory cytokines, such as IL-8, are up-regulated in the endometria of patients with pelvic inflammatory disease. UDP-glucose stimulated IL-8 production via P2RY14 in human endometrial epithelial cells but not stromal cells. Furthermore, UDP-glucose enhanced neutrophil chemotaxis in the presence of a human endometrial epithelial cell line in an IL-8-dependent manner. Administration of UDP-glucose into the mouse uterus induced expression of macrophage inflammatory protein-2 and keratinocyte-derived cytokine, two murine chemokines that are functional homologues of IL-8, and augmented endometrial neutrophil recruitment. Reduced expression of P2RY14 by small interfering RNA gene silencing attenuated LPS- or UDP-glucose-induced leukocytosis in the mouse uterus. These results suggest that UDP-glucose and its receptor P2RY14 are key front line players able to trigger innate mucosal immune responses in the FRT bypassing the recognition of pathogen-associated molecular patterns. Our findings would significantly impact the strategic design of therapies to modulate mucosal immunity by targeting P2RY14.


Asunto(s)
Genitales Femeninos/patología , Inmunidad Innata , Interleucina-8/genética , Membrana Mucosa/inmunología , Receptores Purinérgicos P2/fisiología , Regulación hacia Arriba/genética , Animales , Quimiotaxis , Endometrio/metabolismo , Endometrio/patología , Epitelio/metabolismo , Femenino , Genitales Femeninos/inmunología , Humanos , Interleucina-8/biosíntesis , Ratones , Neutrófilos/fisiología , Receptores Purinérgicos P2Y , Uridina Difosfato Glucosa/farmacología , Útero
20.
Fertil Steril ; 91(3): 929.e1-3, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18990380

RESUMEN

OBJECTIVE: To describe a case of uterine pseudoaneurysm after laparoscopic myomectomy in a 36-year-old woman. DESIGN: Case report. SETTING: University hospital. PATIENT(S): A 36-year-old woman, 3 months after laparoscopic myomectomy, presenting with an intrauterine hypoechoic lesion measuring 5 cm in diameter. INTERVENTION(S): Uterine pseudoaneurysm was diagnosed by color Doppler ultrasound. MAIN OUTCOME MEASURE(S): Complete resolution of the pseudoaneurysm. RESULT(S): Spontaneous thrombosis was observed in the pseudoaneurysm. At 6-month follow-up, the uterus appeared normal. CONCLUSION(S): Our case presents the possibility of delayed occurrence of uterine pseudoaneurysm after laparoscopic myomectomy.


Asunto(s)
Aneurisma Falso/etiología , Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Laparoscopía/efectos adversos , Miometrio/cirugía , Útero/irrigación sanguínea , Adulto , Aneurisma Falso/diagnóstico , Angiografía , Arterias/patología , Femenino , Humanos , Leiomioma/cirugía , Imagen por Resonancia Magnética , Metrorragia/etiología , Remisión Espontánea , Trombosis/etiología , Ultrasonografía Doppler en Color , Neoplasias Uterinas/cirugía
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