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1.
Am J Physiol Regul Integr Comp Physiol ; 327(1): R54-R65, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38738295

RESUMO

Obesity is a major public health issue due to its association with type 2 diabetes, hypertension, and other cardiovascular risks. The BBSome, a complex of eight conserved Bardet-Biedl syndrome (BBS) proteins, has emerged as a key regulator of energy and glucose homeostasis as well as cardiovascular function. However, the importance of adipocyte BBSome in controlling these physiological processes is not clear. Here, we show that adipocyte-specific constitutive disruption of the BBSome through selective deletion of the Bbs1 gene adiponectin (AdipoCre/Bbs1fl/fl mice) does not affect body weight under normal chow or high-fat and high-sucrose diet (HFHSD). However, constitutive BBSome deficiency caused impairment in glucose tolerance and insulin sensitivity. Similar phenotypes were observed after inducible adipocyte-specific disruption of the BBSome (AdipoCreERT2/Bbs1fl/fl mice). Interestingly, a significant increase in renal sympathetic nerve activity, measured using multifiber recording in the conscious state, was observed in AdipoCre/Bbs1fl/fl mice on both chow and HFHSD. A significant increase in tail-cuff arterial pressure was also observed in chow-fed AdipoCre/Bbs1fl/fl mice, but this was not reproduced when arterial pressure was measured by radiotelemetry. Moreover, AdipoCre/Bbs1fl/fl mice had no significant alterations in vascular reactivity. On the other hand, AdipoCre/Bbs1fl/fl mice displayed impaired baroreceptor reflex sensitivity when fed HFHSD, but not on normal chow. Taken together, these data highlight the relevance of the adipocyte BBSome for the regulation of glucose homeostasis and sympathetic traffic. The BBSome also contributes to baroreflex sensitivity under HFHSD, but not normal chow.NEW & NOTEWORTHY The current study show how genetic manipulation of fat cells impacts various functions of the body including sensitivity to the hormone insulin.


Assuntos
Adipócitos , Adiponectina , Animais , Adipócitos/metabolismo , Adiponectina/metabolismo , Adiponectina/genética , Camundongos , Resistência à Insulina , Masculino , Obesidade/fisiopatologia , Obesidade/metabolismo , Obesidade/genética , Camundongos Knockout , Sistema Nervoso Simpático/fisiopatologia , Dieta Hiperlipídica , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Doenças do Sistema Nervoso Autônomo/genética , Doenças do Sistema Nervoso Autônomo/metabolismo , Síndrome de Bardet-Biedl/genética , Síndrome de Bardet-Biedl/fisiopatologia , Síndrome de Bardet-Biedl/metabolismo , Proteínas Associadas aos Microtúbulos
2.
Eur J Appl Physiol ; 124(7): 2209-2223, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38441691

RESUMO

INTRODUCTION: Strength training mitigates the age-related decline in strength and muscle activation but limited evidence exists on specific motor pathway adaptations. METHODS: Eleven young (22-34 years) and ten older (66-80 years) adults underwent five testing sessions where lumbar-evoked potentials (LEPs) and motor-evoked potentials (MEPs) were measured during 20 and 60% of maximum voluntary contraction (MVC). Ten stimulations, randomly delivered, targeted 25% of maximum compound action potential for LEPs and 120, 140, and 160% of active motor threshold (aMT) for MEPs. The 7-week whole-body resistance training intervention included five exercises, e.g., knee extension (5 sets) and leg press (3 sets), performed twice weekly and was followed by 4 weeks of detraining. RESULTS: Young had higher MVC (~ 63 N·m, p = 0.006), 1-RM (~ 50 kg, p = 0.002), and lower aMT (~ 9%, p = 0.030) than older adults at baseline. Young increased 1-RM (+ 18 kg, p < 0.001), skeletal muscle mass (SMM) (+ 0.9 kg, p = 0.009), and LEP amplitude (+ 0.174, p < 0.001) during 20% MVC. Older adults increased MVC (+ 13 N·m, p = 0.014), however, they experienced decreased LEP amplitude (- 0.241, p < 0.001) during 20% MVC and MEP amplitude reductions at 120% (- 0.157, p = 0.034), 140% (- 0.196, p = 0.026), and 160% (- 0.210, p = 0.006) aMT during 60% MVC trials. After detraining, young and older adults decreased 1-RM, while young adults decreased SMM. CONCLUSION: Higher aMT and MEP amplitude in older adults were concomitant with lower baseline strength. Training increased strength in both groups, but divergent modifications in cortico-spinal activity occurred. Results suggest that the primary locus of adaptation occurs at the spinal level.


Assuntos
Potencial Evocado Motor , Músculo Quadríceps , Treinamento Resistido , Humanos , Treinamento Resistido/métodos , Idoso , Masculino , Adulto , Feminino , Potencial Evocado Motor/fisiologia , Músculo Quadríceps/fisiologia , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Adaptação Fisiológica/fisiologia , Adulto Jovem , Força Muscular/fisiologia , Córtex Motor/fisiologia , Contração Muscular/fisiologia , Medula Espinal/fisiologia
3.
Am J Physiol Endocrinol Metab ; 325(6): E711-E722, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37909854

RESUMO

The BBSome is a protein complex composed of eight Bardet-Biedl syndrome (BBS) proteins including BBS1. Humans and mice lacking a functional BBSome display obesity and type 2 diabetes, highlighting the importance of this protein complex for metabolic regulation. However, the contribution of the BBSome in insulin-sensitive tissues such as skeletal muscle and liver to metabolic regulation is ill-defined. Here, we show that disruption of the BBSome through Bbs1 gene deletion in the skeletal muscle had no effect on body weight or glucose handling, but improved insulin sensitivity of female mice without changing insulin receptor signaling. Interestingly, when fed an obesogenic diet, male mice lacking the Bbs1 gene in skeletal muscle exhibited heightened insulin sensitivity despite the comparable weight gain and glucose tolerance relative to controls. On the other hand, normal chow-fed mice missing the Bbs1 gene in hepatocytes displayed increased body weight, as well as impaired glucose handling and insulin sensitivity. This was associated with attenuated insulin signaling in liver and hepatocytes, but not skeletal muscle and white adipose tissue. Moreover, hepatocytes lacking the Bbs1 gene displayed significant reduction in plasma membrane insulin receptor levels due to the mitochondrial dysfunction evoked by loss of the BBSome. Together, these findings demonstrate that myocyte BBSome is minimally involved in metabolic regulation, whereas the hepatic BBSome plays a critical role in the control of energy homeostasis and insulin sensitivity through its requirement for insulin receptor trafficking.NEW & NOTEWORTHY The ongoing epidemic of obesity and associated illnesses highlights the need to understand the biological processes that regulate energy balance. Here, we identified an important role for a protein complex called BBSome in the control of hepatic function. We show that the liver BBSome is necessary to maintain body weight and blood glucose levels due to its requirements to generate energy and detect insulin, a hormone that is essential for metabolic regulation.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Insulinas , Humanos , Camundongos , Masculino , Feminino , Animais , Proteínas Associadas aos Microtúbulos/metabolismo , Receptor de Insulina , Resistência à Insulina/genética , Diabetes Mellitus Tipo 2/genética , Obesidade/genética , Obesidade/metabolismo , Peso Corporal/genética , Fígado/metabolismo , Glucose , Músculo Esquelético/metabolismo
4.
Am J Physiol Regul Integr Comp Physiol ; 324(2): R161-R170, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36534590

RESUMO

Bsardet Biedl syndrome (BBS) is a genetic condition associated with various clinical features including cutaneous disorders and certain autoimmune and inflammatory diseases pointing to a potential role of BBS proteins in the regulation of immune function. BBS1 protein, which is a key component of the BBSome, a protein complex involved in the regulation of cilia function and other cellular processes, has been implicated in the immune synapse assembly by promoting the centrosome polarization to the antigen-presenting cells. Here, we assessed the effect of disrupting the BBSome, through Bbs1 gene deletion, in T cells. Interestingly, mice lacking the Bbs1 gene specifically in T cells (T-BBS1-/-) displayed normal body weight, adiposity, and glucose handling, but have smaller spleens. However, T-BBS1-/- mice had no change in the proportion and absolute number of B cells and T cells in the spleen and lymph nodes. There was also no alteration in the CD4/CD8 lineage commitment or survival in the thymus of T-BBS1-/- mice. On the other hand, T-BBS1-/- mice treated with Imiquimod dermally exhibited a significantly higher percentage of CD3-positive splenocytes that was due to CD4 but not CD8 T cell predominance. Notably, we found that T-BBS1-/- mice had significantly decreased wound closure, an effect that was more pronounced in males indicating that the BBSome plays an important role in T cell-mediated skin repair. Together, these findings implicate the BBSome in the regulation of selective functions of T cells.


Assuntos
Cílios , Proteínas Associadas aos Microtúbulos , Animais , Masculino , Camundongos , Adiposidade , Cílios/metabolismo , Cílios/patologia , Imunidade/genética , Proteínas Associadas aos Microtúbulos/genética , Síndrome de Bardet-Biedl/genética , Síndrome de Bardet-Biedl/metabolismo
5.
Opt Lett ; 48(11): 2881-2884, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262234

RESUMO

We report on the proof-of-principle experiment of generating carrier-envelope phase (CEP)-controllable and frequency-tunable narrowband terahertz (THz) radiation from an air-plasma filament prescribed by the beat of a temporally stretched two-color laser pulse sequence. The pulse sequence was prepared by propagating the fundamental ultrafast laser pulse through a grating stretcher and Michelson interferometer with variable inter-arm delay. By partially frequency-doubling and focusing the pulse sequence, an air-plasma filament riding a beat note was created to radiate a THz wave with primary pulse characteristics (center frequency and CEP) under coherent control. To reproduce experimental results and elucidate complex nonlinear light-matter interaction, numerical simulation has been performed. This work demonstrates the feasibility of generating coherently controlled narrowband THz wave with high tunability in laser-induced air plasma.

6.
Lipids Health Dis ; 22(1): 34, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882763

RESUMO

The miRNA-181 (miR-181) family regulates neuronal persistence during cerebral ischemia/reperfusion injury (CI/RI). Since the effect of miR-181d on CI/RI has never been studied, the current work sought to determine the involvement of miR-181d in neuronal apoptosis after brain I/R injury. To replicate in vivo and in vitro CI/RI, a transient middle cerebral artery occlusion (tMCAO) model in rats and an oxygen-glucose deficiency/reoxygenation (OGD/R) model in neuro 2A cells were developed. In both in vivo and in vitro stroke models, the expression of miR-181d was considerably higher. miR-181d suppression reduced apoptosis and oxidative stress in OGD/R-treated neuroblastoma cells, but miR-181d overexpression increased both. Furthermore, it was observed that miR-181d has a direct target in dedicator of cytokinesis 4 (DOCK4). The overexpression of DOCK4 partially overcame cell apoptosis and oxidative stress induced by miR-181d upregulation and OGD/R injury. Furthermore, the DOCK4 rs2074130 mutation was related to lower DOCK4 levels in ischemic stroke (IS) peripheral blood and higher susceptibility to IS. These findings suggest that downregulating miR-181d protects neurons from ischemic damage by targeting DOCK4, implying that the miR-181d/DOCK4 axis might be a novel therapeutic target for IS.


Assuntos
Lesões Encefálicas , Proteínas Ativadoras de GTPase , AVC Isquêmico , MicroRNAs , Traumatismo por Reperfusão , Animais , Ratos , Citocinese , Glucose , Hipóxia , MicroRNAs/genética , Neurônios , Oxigênio , Traumatismo por Reperfusão/genética , Proteínas Ativadoras de GTPase/genética
7.
Hepatobiliary Pancreat Dis Int ; 22(3): 263-269, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36435702

RESUMO

BACKGROUND: The effective treatment for hepatocellular carcinoma (HCC) depends on early diagnosis. Previously, the abnormal expression of Wnt3a as the key signaling molecule in the Wnt/ß-catenin pathway was found in HCC cells and could be released into the circulation. In this study, we used rat model of hepatocarcinogenesis to dynamically investigate the alteration of oncogenic Wnt3a and to explore its early monitor value for HCC. METHODS: Sprague-Dawley rats (SD) were fed with diet 2-fluorenylacetamide (2-FAA, 0.05%) for inducing hepatocarcinogenesis, and grouped based on liver morphological alteration by Hematoxylin & Eosin (H&E) staining; rats fed with normal chow were used as normal control (NC). Total RNA and protein were purified from rat livers. Differently expressed genes (DEGs) or Wnt3a mRNA, cellular distribution, and Wnt3a protein levels were analyzed by whole genome microarray with signal logarithm ratio (SLR log2cy5/cy3), immunohistochemistry, and enzyme-linked immunosorbent assay, respectively. RESULTS: Models of rat hepatocarcinogenesis were successfully established based on liver histopathological H&E staining. Rats were divided into the cell degeneration (rDeg), precancerosis (rPre-C) and HCC (rHCC) groups. Total numbers of the up- and down-regulated DEGs with SLR ≥ 8 were 55 and 48 in the rDeg group, 268 and 57 in the rPre-C group, and 312 and 201 in the rHCC group, respectively. Significantly altered genes were involved in cell proliferation, signal transduction, tumor metastasis, and apoptosis. Compared with the NC group, Wnt3a mRNA was increased by 4.6 folds (P < 0.001) in the rDeg group, 7.4 folds (P < 0.001) in the rPre-C group, and 10.4 folds (P < 0.001) in the rHCC group; the positive rates of liver Wnt3a were 66.7% (P = 0.001) in the rDeg group, 100% (P < 0.001) in the rPre-C group, and 100% (P < 0.001) in the rHCC group, respectively. Also, there were significant differences of liver Wnt3a (P < 0.001) or serum Wnt3a (P < 0.001) among different groups. CONCLUSIONS: Overexpression of Wnt3a was associated with rat hepatocarcinogenesis and it should be expected to be a promising monitoring biomarker for HCC occurrence at early stage.


Assuntos
Carcinogênese , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteína Wnt3A , Animais , Ratos , Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Ratos Sprague-Dawley , RNA Mensageiro/metabolismo , Via de Sinalização Wnt , Proteína Wnt3A/análise
8.
Nano Lett ; 22(1): 220-228, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34962400

RESUMO

A strong light-matter interaction is highly desirable from the viewpoint of both fundamental research and practical application. Here, we propose a dielectric-metal hybrid nanocavity composed of a silicon (Si) nanoparticle and a thin gold (Au) film and investigate numerically and experimentally the coupling between the plasmons supported by the nanocavity and the excitons in an embedded tungsten disulfide (WS2) monolayer. When a Si/WS2/Au nanocavity is excited by the surface plasmon polariton generated on the surface of the Au film, greatly enhanced plasmon-exciton coupling originating from the hybridization of the surface plasmon polariton, the mirror-image-induced magnetic dipole, and the exciton modes is clearly revealed in the angle- or size-resolved scattering spectra. A Rabi splitting as large as ∼240 meV is extracted by fitting the experimental data with a coupled harmonic oscillator model containing three oscillators. Our findings open new horizons for constructing nanoscale photonic devices by exploiting dielectric-metal hybrid nanocavities.

9.
Small ; 18(15): e2107467, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35224854

RESUMO

Abnormal tumor metabolism causes the hypoxic microenvironment, which greatly limits the efficacy of photodynamic therapy (PDT). In this work, a strategy of metabolic reprogramming is proposed to economize O2 for enhanced PDT against hypoxic tumors. The carrier-free O2 -economizer (designated as LonCe) is prepared based on the metabolic antitumor drug of Lonidamine (Lon) and the photosensitizer of chlorin e6 (Ce6). By virtue of intermolecular interactions, Lon and Ce6 self-assemble into nanosized LonCe with favorable stability and high drug contents. Compared with Ce6, LonCe exhibits an improved cellular uptake and photodynamic property for tumor treatment. Moreover, LonCe is capable of inhibiting cell metabolism and mitochondrial respiration to remit the tumor hypoxia, which would promote reactive oxygen species (ROS) production and elevate the PDT efficacy on tumor suppression. In vivo experiments indicate that intravenously injected LonCe prefers to accumulate at the tumor site for highly efficient PDT regardless of the hypoxic environment. Besides, the self-delivery LonCe is fabricated without any carriers, which avoids the excipients induced system toxicity and immunogenicity in vivo. This carrier-free nanomedicine with cell respiratory inhibition mechanism would expedite the development and clinical translation of photodynamic nanoplatforms in tumor treatment.


Assuntos
Nanopartículas , Fotoquimioterapia , Porfirinas , Linhagem Celular Tumoral , Excipientes , Humanos , Hipóxia/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/farmacologia , Porfirinas/uso terapêutico , Hipóxia Tumoral
10.
Opt Express ; 30(14): 24676-24688, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237016

RESUMO

The electromagnetically induced transparency (EIT) effect realized in a metasurface is potential for slow light applications for its extreme dispersion variation in the transparency window. Herein, we propose an all-dielectric metasurface to generate a double resonance-trapped quasi bound states in the continuum (BICs) in the form of EIT or Fano resonance through selectively exciting the guiding modes with the grating. The group delay of the EIT is effectively improved up to 2113 ps attributing to the ultrahigh Q-factor resonance carried by the resonance-trapped quasi-BIC. The coupled harmonic oscillator model and a full multipole decomposition are utilized to analyze the physical mechanism of EIT-based quasi-BIC. In addition, the BIC based on Fano and EIT resonance can simultaneously exist at different wavelengths. These findings provide a new feasible platform for slow light devices in the near-infrared region.

11.
Opt Lett ; 47(21): 5595-5598, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219279

RESUMO

To extend the detection range of time-domain spectroscopy into the challenging visible frequencies, we propose an interferometry-type frequency-resolved optical gating (FROG). Our numerical simulation shows that, when operating in a double-pulse scheme, a unique phase-locking mechanism can be activated and preserves both zero- and first-order phases (φ0, φ1)-indispensable for phase-sensitive spectroscopic study-that are otherwise inaccessible to standard FROG measurement. Followed by time-domain signal reconstruction and analysis protocol, we show that time-domain spectroscopy with sub-cycle temporal resolution is enabled and well suits the need of a ultrafast-compatible and ambiguity-free method for complex dielectric function measurement at visible wavelengths.

12.
Nano Lett ; 21(6): 2453-2460, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33651622

RESUMO

To detect the magnetic component of arbitrary unknown optical fields, a candidate probe must meet a list of demanding requirements, including a spatially isotropic magnetic response, suppressed electric effect, and wide operating bandwidth. Here, we show that a silicon nanoparticle satisfies all these requirements, and its optical magnetism driven multiphoton luminescence enables direct mapping of the magnetic field intensity distribution of a tightly focused femtosecond laser beam with varied polarization orientation and spatially overlapped electric and magnetic components. Our work establishes a powerful nonlinear optics paradigm for probing unknown optical magnetic fields of arbitrary electromagnetic structures, which is not only essential for realizing subwavelength-scale optical magnetometry but also facilitates nanophotonic research in the magnetic light-matter interaction regime.

13.
Small ; 17(40): e2102470, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34480417

RESUMO

Tumor cells adapt to excessive oxidative stress by actuating reactive oxygen species (ROS)-defensing system, leading to a resistance to oxidation therapy. In this work, self-delivery photodynamic synergists (designated as PhotoSyn) are developed for oxidative damage amplified tumor therapy. Specifically, PhotoSyn are fabricated by the self-assembly of chlorine e6 (Ce6) and TH588 through π-π stacking and hydrophobic interactions. Without additional carriers, nanoscale PhotoSyn possess an extremely high drug loading rate (up to 100%) and they are found to be fairly stable in aqueous phase with a uniform size distribution. Intravenously injected PhotoSyn prefer to accumulate at tumor sites for effective cellular uptake. More importantly, TH588-mediated MTH1 inhibition could destroy the ROS-defensing system of tumor cells by preventing the elimination of 8-oxo-2'-deoxyguanosine triphosphate (8-oxo-dG), thereby exacerbating the oxidative DNA damage induced by the photodynamic therapy (PDT) of Ce6 under light irradiation. As a consequence, PhotoSyn exhibit enhanced photo toxicity and a significant antitumor effect. This amplified oxidative damage strategy improves the PDT efficiency with a reduced side effect by increasing the lethality of ROS without generating superabundant ROS, which would provide a new insight for developing self-delivery nanoplatforms in photodynamic tumor therapy in clinic.


Assuntos
Nanopartículas , Fotoquimioterapia , Porfirinas , Linhagem Celular Tumoral , Estresse Oxidativo , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio
14.
Am J Physiol Regul Integr Comp Physiol ; 321(2): R228-R237, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34189960

RESUMO

The mechanistic target of rapamycin complex 1 (mTORC1) signaling complex is emerging as a critical regulator of cardiovascular function with alterations in this pathway implicated in cardiovascular diseases. In this study, we used animal models and human tissues to examine the role of vascular mTORC1 signaling in the endothelial dysfunction associated with obesity. In mice, obesity induced by high-fat/high-sucrose diet feeding for ∼2 mo resulted in aortic endothelial dysfunction without appreciable changes in vascular mTORC1 signaling. On the other hand, chronic high-fat diet feeding (45% or 60% kcal: ∼9 mo) in mice resulted in endothelial dysfunction associated with elevated vascular mTORC1 signaling. Endothelial cells and visceral adipose vessels isolated from obese humans display a trend toward elevated mTORC1 signaling. Surprisingly, genetic disruption of endothelial mTORC1 signaling through constitutive or tamoxifen inducible deletion of endothelial Raptor (critical subunit of mTORC1) did not prevent or rescue the endothelial dysfunction associated with high-fat diet feeding in mice. Endothelial mTORC1 deficiency also failed to reverse the endothelial dysfunction evoked by a high-fat/high-sucrose diet in mice. Taken together, these data show increased vascular mTORC1 signaling in obesity, but this vascular mTORC1 activation appears not to be required for the development of endothelial impairment in obesity.


Assuntos
Endotélio Vascular/enzimologia , Alvo Mecanístico do Complexo 1 de Rapamicina/deficiência , Obesidade/prevenção & controle , Gordura Subcutânea/irrigação sanguínea , Vasodilatação , Animais , Aorta Torácica/enzimologia , Aorta Torácica/fisiopatologia , Estudos de Casos e Controles , Dieta Hiperlipídica , Sacarose Alimentar , Modelos Animais de Doenças , Endotélio Vascular/fisiopatologia , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Artérias Mesentéricas/enzimologia , Artérias Mesentéricas/fisiopatologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/enzimologia , Obesidade/genética , Obesidade/fisiopatologia , Proteína Regulatória Associada a mTOR/deficiência , Proteína Regulatória Associada a mTOR/genética , Transdução de Sinais
15.
J Biochem Mol Toxicol ; 35(6): 1-11, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33759271

RESUMO

Previous studies have suggested that microRNA-186 (miR-186) can be induced under hypoxic conditions, and is associated with apoptosis. This study was undertaken to explore the exact role of this microRNA (miRNA) in the apoptotic death of neurons during cerebral ischemic/reperfusion (I/R) injury. To model cerebral ischemia/reperfusion (I/R) injuries, we utilized a transient middle cerebral artery occlusion approach in rats, as well as a model of oxygen-glucose deprivation/reoxygenation (OGD/R) in Neuro2a cells. We found that in both in vitro and in vivo models of cerebral I/R injuries, levels of miR-186 were markedly decreased. When we overexpressed miR-186, this was associated with a reduction in the apoptotic death of neuroblastoma cells in the OGD/R model system, whereas the opposite was true when this miRNA was instead inhibited. We further found miR-186 to directly target hypoxia-inducible factor 1α (HIF-1α) by interacting with the 3'-untranslated region of this mRNA. When we knocked down HIF-1α, this partially overcame the apoptotic death of cells in response to OGD/R injury and associated miR-186 downregulation. Our findings indicate that miR-186 is able to reduce ischemic injury to neurons at least in part through downregulating HIF-1α, suggesting that the miR-186/HIF-1α axis is a potential therapeutic target for the treatment of ischemic stroke.


Assuntos
Encéfalo/metabolismo , Transtornos Cerebrovasculares/metabolismo , Glucose/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/metabolismo , Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Encéfalo/patologia , Linhagem Celular , Transtornos Cerebrovasculares/patologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia
16.
BMC Musculoskelet Disord ; 22(1): 383, 2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33894744

RESUMO

BACKGROUND: Symptomatic pulmonary embolism (PE) after knee arthroscopy is extremely rare. If the embolism is not treated promptly, the patient may die. Bilateral pulmonary embolism with associated pulmonary infarct without concomitant deep vein thrombosis has never been reported following routine knee arthroscopy. CASE PRESENTATION: A 50-year-old female patient with no other risk factors other than hypertension, obesity, varicose veins in the ipsilateral lower extremities and elevated triglyceride (TG) presented to our ward. She had experienced sudden chest tightness, polypnea and fainting after going to the bathroom the morning of the second postoperative day and received emergency medical attention. Colour ultrasonography of the extremities showed no deep vein thrombosis. Lung computed tomography angiography (CTA) showed multiple embolisms scattered in both pulmonary artery branches. Thus, emergency interventional thrombolysis therapy was performed, followed by postoperative symptomatic treatment with drugs with thrombolytic, anticoagulant and protective activities. One week later, lung CTA showed a significant improvement in the PEs compared with those in the previous examination. Since the aetiology of PE and no obvious symptoms were discerned, the patient was discharged. CONCLUSION: Although knee arthroscopy is a minimally invasive and quick procedure, the risk factors for PE in the perioperative period should be considered and fully evaluated to enhance PE detection. Moreover, a timely diagnosis and effective treatment are important measures to prevent and cure PE after knee arthroscopy. Finally, clear guidelines regarding VTE thromboprophylaxis following knee arthroscopy in patients with a low risk of VTE development are needed.


Assuntos
Embolia Pulmonar , Tromboembolia Venosa , Trombose Venosa , Anticoagulantes , Artroscopia/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/etiologia , Fatores de Risco , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia
17.
J Obstet Gynaecol Res ; 47(2): 621-630, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33210403

RESUMO

AIM: MiR-326 has been investigated to be correlated with multiple types of malignancies; however, the role of miR-326 in endometrial cancer (EC) remains rarely reported. The aim of our research is to investigate the functions of miR-326 in EC and the potential molecular mechanism. METHODS: RT-qPCR was performed to compare the expression of miR-326 and Bcl-2 in normal endometrial epithelial cell line (End1/e6e7) and EC cells lines (HEC-1A, Ishikawa), respectively. Bioinformatic analysis and luciferase assay verified the relationship between miR-326 and the 3'-UTR of Bcl-2. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, soft agar colony formation assay and the flow cytometry were performed to investigate the functions of miR-326 and Bcl-2 on proliferation and apoptosis in EC. Western blotting was employed to explore the expression of Bcl-2, Bcl2-associated X (Bax) and caspase-3. RESULTS: The expression of miR-326 decreased in EC cell lines compared to normal endometrial epithelial cell line, while Bcl-2 expression was increased in EC cells. Results of MTT and soft agar colony formation assays showed that miR-326 suppressed proliferation in EC cells. In addition, flow cytometry revealed that miR-326 promoted apoptosis in EC cells. Western blotting showed that silencing miR-326 promoted the expression of Bcl-2. Bioinformatics analysis and luciferase assay verified the 3'-UTR of Bcl-2 was a target of miR-326. Furthermore, MTT assay, soft agar colony formation assay and the flow cytometry proved that miR-326 acts as tumor suppressor via inhibiting the expression of Bcl-2. CONCLUSION: MiR-326 acts as a cancer suppressor to inhibit proliferation and promote apoptosis via targeting Bcl-2 axis in EC.


Assuntos
Neoplasias do Endométrio , MicroRNAs , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Endométrio/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-bcl-2
18.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361712

RESUMO

The genus Maytenus is a member of the Celastraceae family, of which several species have long been used in traditional medicine. Between 1976 and 2021, nearly 270 new compounds have been isolated and elucidated from the genus Maytenus. Among these, maytansine and its homologues are extremely rare in nature. Owing to its unique skeleton and remarkable bioactivities, maytansine has attracted many synthetic endeavors in order to construct its core structure. In this paper, the current status of the past 45 years of research on Maytenus, with respect to its chemical and biological activities are discussed. The chemical research includes its structural classification into triterpenoids, sesquiterpenes and alkaloids, along with several chemical synthesis methods of maytansine or maytansine fragments. The biological activity research includes activities, such as anti-tumor, anti-bacterial and anti-inflammatory activities, as well as HIV inhibition, which can provide a theoretical basis for the better development and utilization of the Maytenus.


Assuntos
Alcaloides/química , Maitansina/análogos & derivados , Maytenus/química , Compostos Fitoquímicos/química , Sesquiterpenos/química , Triterpenos/química , Alcaloides/classificação , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Fármacos Anti-HIV/química , Fármacos Anti-HIV/isolamento & purificação , Fármacos Anti-HIV/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Humanos , Maitansina/isolamento & purificação , Maitansina/farmacologia , Maytenus/metabolismo , Estrutura Molecular , Compostos Fitoquímicos/classificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Plantas Medicinais , Sesquiterpenos/classificação , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Relação Estrutura-Atividade , Triterpenos/classificação , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
19.
Zhonghua Nan Ke Xue ; 27(11): 1006-1010, 2021 Nov.
Artigo em Zh | MEDLINE | ID: mdl-37422873

RESUMO

Objective: To investigate the effect of the application of scrotal midline raphe flaps in surgical repair of hypospadias with penile skin defects. METHODS: We retrospectively analyzed the clinical data on 20 cases of hypospadias with penile skin defects from January 2017 to July 2019. The patients ranged in age from 3 to 12 (mean 6.5) years, with a history of 0-4 (mean 2.4) times of penile surgery. The urethral orifice was located in the midshaft of the penis or perineum, without urethral fistula or narrowing of the outer urethral orifice. We performed ubularized incised plate (TIP) repair of the penile skin defects with scrotal midline raphe flaps and followed up the patients for 7-30 (mean 18.4) months postoperatively. RESULTS: The flaps survived well without necrosis in all the cases, and 18 (90%) of the cases were cured in the first stage. Two of the patients developed urethral fistula after removal of the catheter, which was successfully repaired at 6 months after the first operation. All the patients achieved smooth urination with no urethral stricture. The urinary flow rate was 5-9 (mean 6.5) ml/s at 6 months postoperatively. All were satisfied with the appearance of the penis and scrotum. CONCLUSIONS: The scrotal midline raphe flap, with rich blood supply and good ductility, is suitable for repair of penile skin defects. And TIP repair with the scrotal midline raphe flap, with the advantages of simple operation, few complications and good appearance of the penis and scrotum, is worthy of clinical application.

20.
Opt Express ; 28(13): 18693-18706, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32672164

RESUMO

Solid quantum repeater is a core part in a large-scale quantum network. Entanglement purification, the key technique in a quantum repeater, is used to distill high-quality nonlocal entanglement from an ensemble in a mixed entangled state and to depress the vicious influence on quantum information carriers caused by noise. Here, we present an imperfect-interaction-free entanglement purification on nonlocal electron spins in quantum dots for solid quantum repeaters, using faithful parity check on electron spins. The faithful parity check can make correct judgement on the parity mode without destructing the nonlocal solid entanglement even with the imperfect interaction between a QD embedded inside a microcavity and a circularly polarized photon in the nearly realistic condition. Therefore, the imperfect-interaction-free entanglement purification can prevent the maximally entangled states from being changed into partially entangled ones and guarantee the fidelity of the nonlocal mixed state to a desired one after purification. As this scheme is feasible in the nearly realistic condition with imperfect interaction, the requirements for experimental implementation will be relaxed. These distinctive features make this imperfect-interaction-free entanglement purification have more practical applications in solid quantum repeaters for a large-scale quantum network.

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