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Background: The incidence of hepatocellular carcinoma (HCC) in patients with hepatitis B virus (HBV) is extremely high. MicroRNAs (miRNAs) are a type of endogenous non-coding small RNA with novel molecular therapeutic mechanisms that plays an important role in the occurrence and development of cancers. This study aimed to explore the regulation mechanism of miR-135a and HOXA10 in the proliferation, invasion, and apoptosis of HCC cells. Methods: Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis was used to detect the expression level of miR-135a. Overexpression of miR-135a was used to measure the roles of miR-135a in the proliferation, invasion, and apoptosis of HCC cells. A dual luciferase experiment was performed to assess the relationship between HOXA10 and miR-135a. Western blot was applied to observe the protein levels of p-p38, p-ERK, and p-JNK. Results: The expression levels of miR-135a were significantly decreased in HCC tissues and cells. Overexpression of miR-135a inhibited the proliferation and invasion but promoted the apoptosis of HCC cells. Importantly, our results confirmed that HOXA10 was a direct target of miR-135a. Under HBV infection, silencing of HOXA10 significantly blocked the proliferation and invasion and promoted the apoptosis of HCC cells. In addition, miR-135a/HOXA10 regulated the expressions of p-p38, p-ERK, and p-JNK through the miR-135a/HOXA10 axis, thereby inhibiting the activation of the MAPK pathway. Conclusions: HBV promoted the proliferation and invasion, and inhibited the apoptosis of HCC cells by regulating the miR-135a/HOXA10 pathway. These findings provide a theoretical basis for improving the treatment of HBV-infected HCC patients.
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Hepatocellular carcinoma (HCC) is currently one of the most common tumors, with a high morbidity and mortality rate. HCC induced by persistent hepatitis B virus (HBV) infection is the most common liver cancer subtype at present, and HBV-related HCC is highly malignant and its development mechanism still needs to be explored in depth. This study aimed to explore the molecular mechanism of hsa_circ_0000847 targeting miR-135a-5p (miR-135a) to regulate the proliferation, invasion, and apoptosis of liver cancer cells. The study found that the expression level of hsa_circ_0000847 in liver cancer tissues and cells was significantly increased, while the expression level of miR-135a was significantly decreased. Hsa_circ_0000847 promoted the proliferation of liver cancer cells and elevated the expression of the proliferation-related protein. In addition, hsa_circ_0000847 could promote the invasion of HBV-infected liver cancer cells and inhibit the cell apoptosis of liver cancer cells. At the same time, it significantly promoted the expression of antiapoptotic proteins and inhibited the expression of proapoptotic protein. Interestingly, the dual luciferase experiment proved that hsa_circ_0000847 directly targeted miR-135a. On the other hand, the combined effect of hsa_circ_0000847 and miR-135a further illustrated the effect of hsa_circ_0000847 on the proliferation, invasion, and apoptosis of liver cancer cells. In addition, further experiments have also found that HBV could promote the expression of p-p38, p-ERK, and p-JNK through the hsa_circ_0000847/miR-135a axis, thereby further activating the MAPK pathway. In short, HBV promotes the proliferation and invasion of liver cancer cells and inhibits apoptosis by regulating the hsa_circ_0000847/miR-135a pathway, which provided a theoretical basis for effective treatment of HBV-infected liver cancers.
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BACKGROUND: Autologous nerve transplantation has become the gold standard for other nerve repair methods. But conventional epineurial sutures is prone to misaligned sutures, erroneous axonal growth, and unsatisfactory repair. Finding a new, more effective nerve coaptation method to improve the efficacy of peripheral nerve repair remains an urgent clinical challenge. In this study, the repair efficacies of oblique nerve coaptations for sciatic nerve injury at various angles were observed, providing a theoretical foundation for further clinical applications. METHODS: Sixty-four Sprague-Dawley rats were randomized into four groups of 16. The autologous nerve transplantation model was established by severing and rejoining in situ a 10-mm segment of the sciatic nerve trunk at the angle of 30° (group A), 45° (group B), 60° (group C), or 90° (group D). Sciatic function index (SFI) measurement, measurement of the recovery rate of the wet weight of the triceps surae, electrophysiological examination of nerves, histological examinations, and image analysis were carried out 12 weeks after surgery. RESULTS: The SFI, the recovery rate of the wet weight of the triceps surae, the electrophysiological function of nerves, histological examinations, and image analysis 12 weeks after surgery indicated that all indices of groups A and B were significantly better than those of groups C and D (P<0.05). There was no significant difference between groups A and B or between groups C and D (P>0.05), although group C exhibited a trend of better recovery than group D. CONCLUSIONS: Oblique nerve coaptation at 30-45° in autologous nerve transplantation may significantly enhance nerve regeneration.
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Kinesins constitute a protein superfamily that belongs to the motor protein group. Kinesins move along microtubules to exert their various functions, which include intracellular transportation, mitosis, and cell formation. Kinesins are responsible for the transport of various membrane organelles, protein complexes, mRNA and other material, as well as the regulation of intracellular molecular signal pathways. Cumulative studies have also indicated that kinesins are related to the development of a variety of human diseases. At present, there are 14 subfamilies of the kinesin superfamily (KIFs), comprising 45 members. KIF3 is the most common expression in KIFs. KIF3 is a complex composed of a KIF3A/3B heterodimer and a kinesin-related protein, known as KAP3. These complexes are organelles and protein complexes involved in membrane binding in various tissues and transport within cells (nerve cells, melanocytes, epithelial cells, etc.). As a member of the KIF3 subfamily, KIF3B is an essential protein that can regulate cell migration, and proliferation and has critical biological functions. During mitosis, KIF3B is responsible for vesicle transport and membrane expansion, thus regulating cell migration. In recent years, more and more attention has been paid to the relationship between KIF3B and the occurrence and development of diseases. This article reviews the recent advances in the study of KIF3B and its related diseases.
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Acute spinal cord injury (SCI) results in long-lasting functional impairments through both mechanical damage as well as secondary mechanisms, with limited available therapeutic options. ß-Carotene has been demonstrated to exert biological and pharmacological activities. We aimed to examine the protective effects of ß-carotene in a SCI rat model. We tested the hind-limb locomotor function, neuro-inflammation, oxidative stress, astrocyte activation and nuclear factor-κB (NF-κB) pathway activation of SCI rats, with or without ß-carotene treatment. ß-Carotene substantially improved locomotion that was reduced by SCI. ß-Carotene also relieved SCI-induced oxidative stress via regulation of reactive oxygen species, malondialdehyde, nitric oxide, and superoxide dismutase, as well as restored SCI-suppressed protein expressions of Nrf2 and HO-1. Additionally, ß-carotene decreased the generation of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1ß, interleukin-18 and cyclooxygenase-2, and inhibited the activation of astrocyte in the spinal cord. Furthermore, ß-carotene treatment markedly inhibited the NF-κB pathway activation. Our findings demonstrated that ß-carotene effectively reduced the progression of secondary injury events following SCI through preventing NF-κB pathway activation. Therefore, ß-carotene may be an effective candidate for treating SCI.
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Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Astrócitos/efeitos dos fármacos , Inflamação Neurogênica/tratamento farmacológico , Traumatismos da Medula Espinal/tratamento farmacológico , beta Caroteno/uso terapêutico , Animais , Astrócitos/fisiologia , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Masculino , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de SinaisRESUMO
Exploitation of the heterosis of hybrid rice has shown great success in the improvement of rice yields. However, few genotypes exhibit strong restoration ability as effective restorers of cytoplasmic male sterility (CMS) in the development of hybrid rice. In this study, we developed a platform for the breeding by design of CMS restorer lines based on a library of chromosomal single segment substitution lines (SSSLs) in the Huajingxian74 (HJX74) genetic background. The target genes for breeding by design, Rf34 and Rf44, which are associated with a strong restoration ability, and gs3, gw8, Wxg1 and Alk, which are associated with good grain quality, were selected from the HJX74 SSSL library. Through pyramiding of the target genes, a restorer line, H121R, was developed. The H121R line was then improved regarding blast resistance by pyramiding of the qBLAST11 gene. Hence, a new restorer line with blast resistance, H131R, was developed. The platform involving the Rf34 and Rf44 restorer genes would be used for the continuous improvement of restorer lines through breeding by design in rice.
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We report electroluminescence (EL) measurements carried out on three-terminal devices incorporating individual n-type CdSe nanowires. Simultaneous optical and electrical measurements reveal that EL occurs near the contact between the nanowire and a positively biased electrode or drain. The surface potential profile, obtained by using Kelvin probe microscopy, shows an abrupt potential drop near the position of the EL spot, while the band profile obtained from scanning photocurrent microscopy indicates the existence of an n-type Schottky barrier at the interface. These observations indicate that light emission occurs through a hole leakage or an inelastic scattering induced by the rapid potential drop at the nanowire-electrode interface.
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We report the synthesis and characterization of axial nanorod heterostructures composed of cadmium selenide (CdSe) and cadmium sulfide (CdS). The synthesis employs a solution-liquid-solid (SLS) mechanism with the assistance of bismuth nanocrystals adhered to a substrate (silicon or a III-V semiconductor). Transmission electron microscopy (TEM) and diffraction studies show that CdSe and CdS segments exhibit the wurtzite (hexagonal) crystal structure with <5% stacking faults. Both of these segments grow along the [002] direction with an epitaxial interface between them. Energy-dispersive X-ray (EDX) spectrometry using a high-resolution TEM operating in scanning mode confirms the alloy-free composition modulation in the nanorod heterostructures, showing that Se and S are localized in the CdSe and CdS portions of the nanorod heterostructures, respectively. This study demonstrates that SLS synthesis provides an alternate route to prepare axial nanorod heterostructures that have been difficult to generate using either vapor-liquid-solid growth or catalyst-free solution-phase synthesis.
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We report the observation of a current-driven metal (M)-insulator (I) phase oscillation in two-terminal devices incorporating individual WxV1-xO2 nanobeams connected to parallel shunt capacitors. The frequency of the phase oscillation reaches above 5 MHz for approximately 1 mum long devices. The M-I phase oscillation, which coincides with the charging/discharging of the capacitor, occurs through the axial drift of a single M-I domain wall driven by Joule heating and the Peltier effect.
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We investigated the effect of substrate-induced strain on the metal-insulator transition (MIT) in single-crystalline VO(2) nanobeams. A simple nanobeam-substrate adhesion leads to uniaxial strain along the nanobeam length because of the nanobeam's unique morphology. The strain changes the relative stability of the metal (M) and insulator (I) phases and leads to spontaneous formation of periodic, alternating M-I domain patterns during the MIT. The spatial periodicity of the M-I domains can be modified by changing the nanobeam thickness and the Young's modulus of the substrate.
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Nanoestruturas/química , Compostos de Vanádio/química , Cristalização , Elasticidade , Condutividade Elétrica , Nanoestruturas/ultraestrutura , Óxidos/química , Estresse Mecânico , TransdutoresRESUMO
We report scanned probe characterizations of the ferroelectric phase transition in individual barium titanate (BaTiO3) nanowires. Variable-temperature electrostatic force microscopy is used to manipulate, image, and evaluate the diameter-dependent stability of ferroelectric polarizations. These measurements show that the ferroelectric phase transition temperature (TC) is depressed as the nanowire diameter (dnw) decreases, following a 1/dnw scaling. The diameter at which TC falls below room temperature is determined to be approximately 3 nm, and extrapolation of the data indicates that nanowires with dnw as small as 0.8 nm can support ferroelectricity at lower temperatures. We also present density functional theory (DFT) calculations of bare and molecule-covered BaTiO3 surfaces. These calculations indicate that ferroelectricity in nanowires is stabilized by molecular adsorbates such as OH and carboxylates. These adsorbates are found to passivate polarization charge more effectively than metallic electrodes, explaining the observed stability of ferroelectricity in small-diameter BaTiO3 nanowires.
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Compostos de Bário/química , Compostos de Bário/efeitos da radiação , Eletroquímica/métodos , Magnetismo , Nanotubos/química , Titânio/química , Titânio/efeitos da radiação , Anisotropia , Compostos de Bário/análise , Cristalização/métodos , Condutividade Elétrica , Campos Eletromagnéticos , Teste de Materiais , Conformação Molecular , Nanotubos/efeitos da radiação , Nanotubos/ultraestrutura , Transição de Fase , Titânio/análise , Temperatura de TransiçãoRESUMO
We report the fabrication and characterization of light-emitting transistors incorporating individual cadmium selenide (CdSe) nanocrystals. Electrical measurements conducted at low bias voltage and low temperature show clear evidence of Coulomb blockade behavior, indicating that electrons pass through the nanocrystal by single-electron tunneling. Once the bias voltage exceeds the band gap of CdSe, devices with asymmetric tunnel barriers emit linearly polarized light. Combined analyses of the electrical and optical data indicate that the tunnel couplings between the nanorod and the metallic electrodes change significantly as a function of bias voltage and light emission results from the inelastic scattering of tunneling electrons.