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1.
BMC Ophthalmol ; 23(1): 217, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37193956

RESUMO

PURPOSE: To present the clinical features of thyroid-associated ophthalmopathy (TAO) with different CT types, and to report the outcomes of endoscopic orbital decompression combined with fat decompression (EOD-FD). PATIENTS AND METHODS: Thirty-four patients with TAO who underwent EOD-FD between December 2020 and March 2022 in the Ophthalmology Department of Li Huili Hospital Affiliated with Ningbo University, were included in this retrospective interventional case series. Patients were categorized into two groups based on the results of computerized tomography (CT) scans: muscle expansion type and fat hyperplasia type. RESULTS: Thirty-four TAO patients (55 eyes) were included in this study, and the mean age was 38.62 years (range 22-60 years). The average eye protrusion (EP) reduced from preoperative 23.20 mm to postoperative 19.66 mm (p < 0.0001). Mean intraocular pressure (IOP) decreased from 20.11 mmHg at baseline to 17.29 mmHg postoperatively (p < 0.0001), with a reduction of 2.84 mmHg (14.12%). Twenty cases of muscle expansion and fourteen cases of fat hyperplasia were definite by CT imaging. The mean IOP in the muscle expansion group was higher than that in the fat hyperplasia group (p < 0.05). Elevated intraocular pressure (IOP) occurred in 23 eyes (36.11%), and it was associated with extraocular muscle involvement, gender, and EP. In 3 cases of impaired vision, the mean best corrected visual acuity (VA) improved from 0.4 preoperatively to 0.84 postoperatively (p < 0.01). There were 8 cases with visual field (VF) damage and/or corneal epithelium damage, and all these damages were reversible. CONCLUSION: In this study, we describe the clinical features and experience of EOD-FD in patients with TAO. EOD-FD is an effective technique in reducing IOP and proptosis, with a low incidence of postoperative diplopia.


Assuntos
Exoftalmia , Oftalmopatia de Graves , Adulto , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Descompressão , Oftalmopatia de Graves/cirurgia , Hiperplasia , Órbita/diagnóstico por imagem , Órbita/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Endoscopia
2.
Proc Natl Acad Sci U S A ; 117(17): 9194-9201, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32295882

RESUMO

Promotion of C-C bonds is one of the key fundamental questions in the field of CO2 electroreduction. Much progress has occurred in developing bulk-derived Cu-based electrodes for CO2-to-multicarbons (CO2-to-C2+), especially in the widely studied class of high-surface-area "oxide-derived" copper. However, fundamental understanding into the structural characteristics responsible for efficient C-C formation is restricted by the intrinsic activity of these catalysts often being comparable to polycrystalline copper foil. By closely probing a Cu nanoparticle (NP) ensemble catalyst active for CO2-to-C2+, we show that bias-induced rapid fusion or "electrochemical scrambling" of Cu NPs creates disordered structures intrinsically active for low overpotential C2+ formation, exhibiting around sevenfold enhancement in C2+ turnover over crystalline Cu. Integrating ex situ, passivated ex situ, and in situ analyses reveals that the scrambled state exhibits several structural signatures: a distinct transition to single-crystal Cu2O cubes upon air exposure, low crystallinity upon passivation, and high mobility under bias. These findings suggest that disordered copper structures facilitate C-C bond formation from CO2 and that electrochemical nanocrystal scrambling is an avenue toward creating such catalysts.

3.
Proc Natl Acad Sci U S A ; 116(47): 23404-23409, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31685626

RESUMO

Phase transitions in halide perovskites triggered by external stimuli generate significantly different material properties, providing a great opportunity for broad applications. Here, we demonstrate an In-based, charge-ordered (In+/In3+) inorganic halide perovskite with the composition of Cs2In(I)In(III)Cl6 in which a pressure-driven semiconductor-to-metal phase transition exists. The single crystals, synthesized via a solid-state reaction method, crystallize in a distorted perovskite structure with space group I4/m with a = 17.2604(12) Å, c = 11.0113(16) Å if both the strong reflections and superstructures are considered. The supercell was further confirmed by rotation electron diffraction measurement. The pressure-induced semiconductor-to-metal phase transition was demonstrated by high-pressure Raman and absorbance spectroscopies and was consistent with theoretical modeling. This type of charge-ordered inorganic halide perovskite with a pressure-induced semiconductor-to-metal phase transition may inspire a range of potential applications.

4.
Reproduction ; 162(1): 95-105, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-33999843

RESUMO

Postovulatory oocyte aging is one of the major causes for human early pregnancy loss and for a decline in the population of some mammalian species. Thus, the mechanisms for oocyte aging are worth exploring. While it is known that ovulated oocytes age within the oviduct and that female stresses impair embryo development by inducing apoptosis of oviductal cells, it is unknown whether the oviduct and/or female stress would affect postovulatory oocyte aging. By comparing aging characteristics, including activation susceptibility, maturation-promoting factor activity, developmental potential, cytoplasmic fragmentation, spindle/chromosome morphology, gene expression, and cumulus cell apoptosis, this study showed that oocytes aged faster in vivo in restraint-stressed mice than in unstressed mice than in vitro. Our further analysis demonstrated that oviductal cells underwent apoptosis with decreased production of growth factors with increasing time after ovulation, and female restraint facilitated apoptosis of oviductal cells. Furthermore, mating prevented apoptosis of oviductal cells and alleviated oocyte aging after ovulation. In conclusion, the results demonstrated that mouse oviducts underwent apoptosis and facilitated oocyte aging after ovulation; female restraint facilitated oocyte aging while enhancing apoptosis of oviductal cells; and copulation ameliorated oviductal apoptosis and oocyte aging.


Assuntos
Envelhecimento , Apoptose , Desenvolvimento Embrionário , Oócitos/patologia , Oviductos/patologia , Ovulação , Estresse Psicológico , Animais , Feminino , Camundongos , Oócitos/metabolismo , Oviductos/metabolismo , Gravidez , Espécies Reativas de Oxigênio/metabolismo , Reprodução , Restrição Física
5.
J Reprod Dev ; 67(1): 43-51, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33310974

RESUMO

It has been reported in recent studies that restraint stress on pregnant mice during the preimplantation stage elevated corticotrophin-releasing hormone (CRH) and glucocorticoid levels in the serum and oviducts; furthermore, CRH and corticosterone (CORT) impacted preimplantation embryos indirectly by triggering the apoptosis of oviductal epithelial cells (OECs) through activation of the Fas system. However, it remains unclear whether TNF-α signaling is involved in CRH- and/or glucocorticoid-induced apoptosis of OECs. In the present study, it was shown that culture with either CRH or CORT induced significant apoptosis of OECs. The culture of OECs with CRH augmented both FasL expression and TNF-α expression. However, culture with CORT increased FasL, but decreased TNF-α, expression significantly. Although knocking down/knocking out FasL expression in OECs significantly ameliorated the proapoptotic effects of both CRH and CORT, knocking down/knocking out TNF-α expression relieved only the proapoptotic effect of CRH but not that of CORT. Taken together, our results demonstrated that CRH-induced OEC apoptosis involved both Fas signaling and TNF-α signaling. Conversely, CORT-induced OEC apoptosis involved only the Fas, but not the TNF-α, signaling pathway. The data obtained are crucial for our understanding of the mechanisms by which various categories of stress imposed on pregnant females impair embryo development, as well as for the development of measures to protect the embryo from the adverse effects of stress.


Assuntos
Apoptose/efeitos dos fármacos , Corticosterona/farmacologia , Células Epiteliais/efeitos dos fármacos , Oviductos/efeitos dos fármacos , Animais , Células Cultivadas , Células Epiteliais/fisiologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , Oviductos/citologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Necrose Tumoral alfa/genética
6.
Proc Natl Acad Sci U S A ; 115(47): 11929-11934, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30397127

RESUMO

Facile ionic transport in lead halide perovskites plays a critical role in device performance. Understanding the microscopic origins of high ionic conductivities has been complicated by indirect measurements and sample microstructural heterogeneities. Here, we report the direct visualization of halide anion interdiffusion in CsPbCl3-CsPbBr3 single crystalline perovskite nanowire heterojunctions using wide-field and confocal photoluminescence measurements. The combination of nanoscale imaging techniques with these single crystalline materials allows us to measure intrinsic anionic lattice diffusivities, free from complications of microscale inhomogeneity. Halide diffusivities were found to be between 10-13 and ∼10-12 cm2/second at about 100 °C, which are several orders of magnitudes lower than those reported in polycrystalline thin films. Spatially resolved photoluminescence lifetimes and surface potential measurements provide evidence of the central role of halide vacancies in facilitating ionic diffusion. Vacancy formation free energies computed from molecular simulation are small due to the easily deformable perovskite lattice, accounting for the high equilibrium vacancy concentration. Furthermore, molecular simulations suggest that ionic motion is facilitated by low-frequency lattice modes, resulting in low activation barriers for vacancy-mediated transport. This work elucidates the intrinsic solid-state ion diffusion mechanisms in this class of semisoft materials and offers guidelines for engineering materials with long-term stability in functional devices.

7.
Proc Natl Acad Sci U S A ; 115(36): 8889-8894, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30127004

RESUMO

Semiconductor p-n junctions are fundamental building blocks for modern optical and electronic devices. The p- and n-type regions are typically created by chemical doping process. Here we show that in the new class of halide perovskite semiconductors, the p-n junctions can be readily induced through a localized thermal-driven phase transition. We demonstrate this p-n junction formation in a single-crystalline halide perovskite CsSnI3 nanowire (NW). This material undergoes a phase transition from a double-chain yellow (Y) phase to an orthorhombic black (B) phase. The formation energies of the cation and anion vacancies in these two phases are significantly different, which leads to n- and p- type electrical characteristics for Y and B phases, respectively. Interface formation between these two phases and directional interface propagation within a single NW are directly observed under cathodoluminescence (CL) microscopy. Current rectification is demonstrated for the p-n junction formed with this localized thermal-driven phase transition.

8.
Nano Lett ; 20(11): 8151-8156, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33052693

RESUMO

Halide perovskites have attracted increasing research attention with regard to their potential for optoelectronic applications. Because of its low activation energy, ion migration is implicated in the long-term stability and many unusual transport behaviors of halide perovskite devices. However, direct observation and precise control of the ionic transport in halide perovskite crystals remain challenging. Here, we have designed an axial CsPbBr3-CsPbCl3 nanowire heterostructure, in which electric-field-induced halide ion migration was clearly visualized and quantified. We demonstrated that halide ion migration is dependent on the applied electric field and exhibits ionic rectification in this solid-state system, which is due to the nonuniform distribution of the ionic vacancies in the nanowire that results from a competition between electrical screening and their creation/destruction at the electrodes' interfaces. The asymmetric heterostructure characteristics add an additional knob to control the ion movement in the design of advanced ionic circuits with halide perovskites as building blocks.

9.
Biol Reprod ; 103(3): 534-547, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32588041

RESUMO

Studies suggested that postovulatory oocyte aging might be prevented by maintaining a high maturation-promoting factor (MPF) activity. Whether AMP-activated protein kinase (AMPK) plays any role in postovulatory oocyte aging is unknown. Furthermore, while activation of AMPK stimulates meiotic resumption in mouse oocytes, it inhibits meiotic resumption in pig and bovine oocytes. Thus, the species difference in AMPK regulation of oocyte MPF activities is worth in-depth studies. This study showed that AMPK activation with metformin or 5-aminoimidazole- 4-carboxamide- 1-beta-d- ribofuranoside and inactivation with compound C significantly increased and decreased, respectively, the activation susceptibility (AS) and other aging parameters in aging mouse oocytes. While AMPK activity increased, MPF activity and cyclic adenosine monophosphate (cAMP) decreased significantly with time post ovulation. In vitro activation and inactivation of AMPK significantly decreased and increased the MPF activity, respectively. MPF upregulation with MG132 or downregulation with roscovitine completely abolished the effects of AMPK activation or inactivation on AS of aging oocytes, respectively. AMPK facilitated oocyte aging with increased reactive oxygen species (ROS) and cytoplasmic calcium. Furthermore, treatment with Ca2+/calmodulin-dependent protein kinase (CaMK) inhibitors significantly decreased AS and AMPK activation. Taken together, the results suggested that AMPK facilitated oocyte aging through inhibiting MPF activities, and postovulatory oocyte aging activated AMPK with decreased cAMP by activating CaMKs via increasing ROS and cytoplasmic calcium.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Oócitos/crescimento & desenvolvimento , Ovulação/fisiologia , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Sinalização do Cálcio/efeitos dos fármacos , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Meios de Cultivo Condicionados , AMP Cíclico/metabolismo , Ativação Enzimática , Feminino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mesotelina , Metformina/farmacologia , Camundongos , Gravidez , Inibidores de Proteínas Quinases/farmacologia , Espécies Reativas de Oxigênio/metabolismo
10.
Proc Natl Acad Sci U S A ; 114(33): 8693-8697, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28760988

RESUMO

Controlling the flow of thermal energy is crucial to numerous applications ranging from microelectronic devices to energy storage and energy conversion devices. Here, we report ultralow lattice thermal conductivities of solution-synthesized, single-crystalline all-inorganic halide perovskite nanowires composed of CsPbI3 (0.45 ± 0.05 W·m-1·K-1), CsPbBr3 (0.42 ± 0.04 W·m-1·K-1), and CsSnI3 (0.38 ± 0.04 W·m-1·K-1). We attribute this ultralow thermal conductivity to the cluster rattling mechanism, wherein strong optical-acoustic phonon scatterings are driven by a mixture of 0D/1D/2D collective motions. Remarkably, CsSnI3 possesses a rare combination of ultralow thermal conductivity, high electrical conductivity (282 S·cm-1), and high hole mobility (394 cm2·V-1·s-1). The unique thermal transport properties in all-inorganic halide perovskites hold promise for diverse applications such as phononic and thermoelectric devices. Furthermore, the insights obtained from this work suggest an opportunity to discover low thermal conductivity materials among unexplored inorganic crystals beyond caged and layered structures.

11.
Zygote ; : 1-10, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31933449

RESUMO

Studies have indicated that psychological stress impairs human fertility and that various stressors can induce apoptosis of testicular cells. However, the mechanisms by which psychological stress on males reduces semen quality and stressors induce apoptosis in testicular cells are largely unclear. Using a psychological (restraint) stress mouse model, we tested whether male psychological stress triggers apoptosis of spermatozoa and spermatogenic cells through activating tumour necrosis factor (TNF)-α signalling. Wild-type or TNF-α-/- male mice were restrained for 48 h before examination for apoptosis and expression of TNF-α and TNF receptor 1 (TNFR1) in spermatozoa, epididymis, seminiferous tubules and spermatogenic cells. The results showed that male restraint significantly decreased fertilization rate and mitochondrial membrane potential, while increasing levels of malondialdehyde, active caspase-3, TNF-α and TNFR1 in spermatozoa. Male restraint also increased apoptosis and expression of TNF-α and TNFR1 in caudae epididymides, seminiferous tubules and spermatogenic cells. Sperm quality was also significantly impaired when spermatozoa were recovered 35 days after male restraint. The restraint-induced damage to spermatozoa, epididymis and seminiferous tubules was significantly ameliorated in TNF-α-/- mice. Furthermore, incubation with soluble TNF-α significantly reduced sperm motility and fertilizing potential. Taken together, the results demonstrated that male psychological stress induces apoptosis in spermatozoa and spermatogenic cells through activating the TNF-α system and that the stress-induced apoptosis in spermatogenic cells can be translated into impaired quality in future spermatozoa.

12.
J Am Chem Soc ; 141(33): 13028-13032, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31386354

RESUMO

The self-assembly of nanoparticles, a process whereby nanocrystal building blocks organize into even more ordered superstructures, is of great interest to nanoscience. Here we report the layer-by-layer assembly of 2D perovskite nanosheet building blocks. Structural analysis reveals that the assembled superlattice nanocrystals match with the layered Ruddlesden-Popper perovskite phase. This assembly proves reversible, as these superlattice nanocrystals can be reversibly exfoliated back into their building blocks via sonication. This study demonstrates the opportunity to further understand and exploit thermodynamics to increase order in a system of nanoparticles and to study emergent optical properties of a superlattice from 2D, weakly attracted, perovskite building blocks.

13.
Nano Lett ; 18(6): 3538-3542, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29771532

RESUMO

Alloying different semiconductors is a powerful approach to tuning the optical and electronic properties of semiconductor materials. In halide perovskites (ABX3), alloys with different anions have been widely studied, and great band gap tunability in the visible range has been achieved. However, perovskite alloys with different cations at the "B" site are less understood due to the synthetic challenges. Herein, we first have developed the synthesis of single-crystalline CsPb xSn1- xI3 nanowires (NWs). The electronic band gaps of CsPb xSn1- xI3 NWs can be tuned from 1.3 to 1.78 eV by varying the Pb/Sn ratio, which leads to the tunable photoluminescence (PL) in the near-infrared range. More importantly, we found that the electrical conductivity increases as more Sn2+ is alloyed with Pb2+, possibly due to the increase of charge carrier concentration when more Sn2+ is introduced. The wide tunability of the optical and electronic properties makes CsPb xSn1- xI3 alloy NWs promising candidates for future optoelectronic device applications.

14.
Biol Reprod ; 99(4): 828-837, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29668880

RESUMO

Mechanisms by which psychological stress damages oocytes are largely undetermined. Although a previous study showed that the stress-induced corticotrophin-releasing hormone (CRH) elevation impaired oocyte competence by triggering apoptosis of ovarian cells, how CRH causes apoptosis in ovarian cells and oocytes is unknown. In this study, we have examined the hypothesis that restraint stress (RS)-induced CRH elevation triggers apoptosis of ovarian cells and impairs oocyte competence through activating the Fas/FasL system. The results showed that RS of female mice impaired oocyte competence, enhanced expression of CRH and CRH receptor (CRH-R) in the ovary, and induced apoptosis while activating the Fas/FasL system in mural granulosa cells (MGCs) and oocytes. Injecting mice with CRH-R1 antagonist antalarmin significantly alleviated the adverse effect of RS on oocyte developmental potential. Treatment of cultured MGCs recapitulated the effects of CRH and antalarmin on apoptosis and Fas/FasL expression in MGCs. Silencing FasL gene by RNA interference in cultured MGCs further confirmed the involvement of the Fas/FasL system in the CRH triggered apoptosis of ovarian cells. It is concluded that the RS-induced CRH elevation triggers apoptosis of ovarian cells and impairs oocyte competence via activation of the Fas/FasL system.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Proteína Ligante Fas/metabolismo , Oócitos/metabolismo , Ovário/citologia , Ovário/metabolismo , Restrição Física/fisiologia , Receptor fas/metabolismo , Animais , Apoptose/fisiologia , Células Cultivadas , Feminino , Células da Granulosa/citologia , Células da Granulosa/metabolismo , Camundongos , Oócitos/citologia , Oócitos/crescimento & desenvolvimento , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Restrição Física/efeitos adversos , Restrição Física/psicologia , Estresse Psicológico
15.
Nano Lett ; 16(9): 5675-80, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27494433

RESUMO

Reducing carbon dioxide with a multicomponent artificial photosynthetic system, closely mimicking nature, represents a promising approach for energy storage. Previous works have focused on exploiting light-harvesting semiconductor nanowires (NW) for photoelectrochemical water splitting. With the newly developed CO2 reduction nanoparticle (NP) catalysts, direct interfacing of these nanocatalysts with NW light absorbers for photoelectrochemical reduction of CO2 becomes feasible. Here, we demonstrate a directed assembly of NP catalysts on vertical NW substrates for CO2-to-CO conversion under illumination. Guided by the one-dimensional geometry, well-dispersed assembly of Au3Cu NPs on the surface of Si NW arrays was achieved with facile coverage tunability. Such Au3Cu NP decorated Si NW arrays can readily serve as effective CO2 reduction photoelectrodes, exhibiting high CO2-to-CO selectivity close to 80% at -0.20 V vs RHE with suppressed hydrogen evolution. A reduction of 120 mV overpotential compared to the planar (PL) counterpart was observed resulting from the optimized spatial arrangement of NP catalysts on the high surface area NW arrays. In addition, this system showed consistent photoelectrochemical CO2 reduction capability up to 18 h. This simple photoelectrode assembly process will lead to further progress in artificial photosynthesis, by allowing the combination of developments in each subfield to create an efficient light-driven system generating carbon-based fuels.

16.
Nano Lett ; 16(7): 4133-40, 2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27243378

RESUMO

Thermal transport in silicon nanowires has captured the attention of scientists for understanding phonon transport at the nanoscale, and the thermoelectric figure-of-merit (ZT) reported in rough nanowires has inspired engineers to develop cost-effective waste heat recovery systems. Thermoelectric generators composed of silicon target high-temperature applications due to improved efficiency beyond 550 K. However, there have been no studies of thermal transport in silicon nanowires beyond room temperature. High-temperature measurements also enable studies of unanswered questions regarding the impact of surface boundaries and varying mode contributions as the highest vibrational modes are activated (Debye temperature of silicon is 645 K). Here, we develop a technique to investigate thermal transport in nanowires up to 700 K. Our thermal conductivity measurements on smooth silicon nanowires show the classical diameter dependence from 40 to 120 nm. In conjunction with Boltzmann transport equation, we also probe an increasing contribution of high-frequency phonons (optical phonons) in smooth silicon nanowires as the diameter decreases and the temperature increases. Thermal conductivity of rough silicon nanowires is significantly reduced throughout the temperature range, demonstrating a potential for efficient thermoelectric generation (e.g., ZT = 1 at 700 K).

17.
J Am Chem Soc ; 138(23): 7236-9, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27213511

RESUMO

Here, we demonstrate the successful synthesis of brightly emitting colloidal cesium lead halide (CsPbX3, X = Cl, Br, I) nanowires (NWs) with uniform diameters and tunable compositions. By using highly monodisperse CsPbBr3 NWs as templates, the NW composition can be independently controlled through anion-exchange reactions. CsPbX3 alloy NWs with a wide range of alloy compositions can be achieved with well-preserved morphology and crystal structure. The NWs are highly luminescent with photoluminescence quantum yields (PLQY) ranging from 20% to 80%. The bright photoluminescence can be tuned over nearly the entire visible spectrum. The high PLQYs together with charge transport measurements exemplify the efficient alloying of the anionic sublattice in a one-dimensional CsPbX3 system. The wires increased functionality in the form of fast photoresponse rates and the low defect density suggest CsPbX3 NWs as prospective materials for optoelectronic applications.

18.
Biol Reprod ; 91(3): 56, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25061094

RESUMO

Although fusion of nucleoli was observed during pronuclear development of zygotes and the behavior of nucleoli in pronuclei has been suggested as an indicator of embryonic developmental potential, the mechanism for nucleolar fusion is unclear. Although both cytoskeleton and the nucleolus are important cellular entities, there are no special reports on the relationship between the two. Role of cytoskeleton in regulating fusion of nucleoli was studied using the activated mouse oocyte model. Mouse oocytes were cultured for 6 h in activating medium (Ca²âº-free CZB medium containing 10 mM SrCl2) supplemented with or without inhibitors for cytoskeleton or protein synthesis before pronuclear formation, nucleolar fusion, and the activity of maturation-promoting factor (MPF) were examined. Whereas treatment with microfilament inhibitor cytochalasin D or B or intermediate filament inhibitor acrylamide suppressed nucleolar fusion efficiently, treatment with microtubule inhibitor demecolcine or nocodazole or protein synthesis inhibitor cycloheximide had no effect. The cytochalasin D- or acrylamide-sensitive temporal window coincided well with the reported temporal window for nucleolar fusion in activated oocytes. Whereas a continuous incubation with demecolcine prevented pronuclear formation, pronuclei formed normally when demecolcine was excluded during the first hour of activation treatment when the MPF activity dropped dramatically. The results suggest that 1) microfilaments and intermediate filaments but not microtubules support nucleolar fusion, 2) proteins required for nucleolar fusion including microfilaments and intermediate filaments are not de novo synthesized, and 3) microtubule disruption prevents pronuclear formation by activating MPF.


Assuntos
Nucléolo Celular/metabolismo , Citoesqueleto/metabolismo , Fator Promotor de Maturação/metabolismo , Oócitos/citologia , Oogênese , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Animais , Nucléolo Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Ectogênese/efeitos dos fármacos , Técnicas de Cultura Embrionária , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Técnicas de Maturação in Vitro de Oócitos , Filamentos Intermediários/efeitos dos fármacos , Filamentos Intermediários/metabolismo , Masculino , Fator Promotor de Maturação/antagonistas & inibidores , Fusão de Membrana/efeitos dos fármacos , Mesotelina , Camundongos Endogâmicos , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Oogênese/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , Estrôncio/farmacologia , Moduladores de Tubulina/farmacologia
19.
Neurotherapeutics ; 21(1): e00297, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38237403

RESUMO

Noninvasive brain stimulation (NIBS) techniques have demonstrated their potential for chronic pain management, yet their efficacy exhibits variability across studies. Refining stimulation targets and exploring additional targets offer a possible solution to this challenge. This study aimed to identify potential brain surface targets for NIBS in treating chronic pain disorders by integrating literature review, neuroimaging meta-analysis, and functional connectivity analysis on 90 chronic low back pain patients. Our results showed that the primary motor cortex (M1) (C3/C4, 10-20 EEG system) and prefrontal cortex (F3/F4/Fz) were the most used brain stimulation targets for chronic pain treatment according to the literature review. The bilateral precentral gyrus (M1), supplementary motor area, Rolandic operculum, and temporoparietal junction, were all identified as common potential NIBS targets through both a meta-analysis sourced from Neurosynth and functional connectivity analysis. This study presents a comprehensive summary of the current literature and refines the existing NIBS targets through a combination of imaging meta-analysis and functional connectivity analysis for chronic pain conditions. The derived coordinates (with integration of the international electroencephalography (EEG) 10/20 electrode placement system) within the above brain regions may further facilitate the localization of these targets for NIBS application. Our findings may have the potential to expand NIBS target selection beyond current clinical trials and improve chronic pain treatment.


Assuntos
Dor Crônica , Estimulação Encefálica Profunda , Humanos , Dor Crônica/terapia , Encéfalo , Estimulação Magnética Transcraniana/métodos , Estimulação Encefálica Profunda/métodos , Manejo da Dor/métodos , Doença Crônica
20.
Zhongguo Zhen Jiu ; 44(6): 703-14, 2024 Jun 12.
Artigo em Zh | MEDLINE | ID: mdl-38867635

RESUMO

In this study, based on the neuroimaging literature Meta analysis retrieved from Neurosynth platform, the scalp stimulation targets for common psychiatric diseases are developed, which provided the stimulation target protocols of scalp acupuncture for attention deficit hyperactivity disorder, autism spectrum disorder, obsessive-compulsive disorder and schizophrenia. The paper introduces the functions of the brain areas that are involved in each target and closely related to the diseases, and lists the therapeutic methods of common acupuncture/scalp acupuncture and common neuromodulation methods for each disease so as to provide the references for clinical practice. Based on the study results above, the paper further summarizes the overlapped stimulation targets undergoing the intervention with scalp acupuncture for common psychiatric diseases, and the potential relationship between these stimulation targets and treatments with acupuncture and moxibustion.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Transtornos Mentais , Neuroimagem , Couro Cabeludo , Humanos , Terapia por Acupuntura/métodos , Transtornos Mentais/terapia , Transtornos Mentais/diagnóstico por imagem , Neuroimagem/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia
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