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1.
Proc Natl Acad Sci U S A ; 120(41): e2304534120, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37782793

RESUMO

Aberrant transcripts expression of the m6A methyltransferase complex (MTC) is widely found across human cancers, suggesting a dysregulated signaling cascade which integrates m6A epitranscriptome to drive tumorigenesis. However, the responsible transcriptional machinery directing the expression of distinct MTC subunits remains unclear. Here, we identified an unappreciated interplay between the histone acetyl-lysine reader BRD4 and the m6A writer complex across human cancers. BRD4 directly stimulates transcripts expression of seven MTC subunits, allowing the maintenance of the nuclear writer complex integrity. Upon BET inhibition, this BRD4-MTC signaling cascade accounts for global m6A reduction and the subsequent dynamic alteration of BRD4-dependent transcriptome, resulting in impaired DNA damage response that involves activation of homologous recombination (HR) repair and repression of apoptosis. We further demonstrated that the combined synergy upon BET/PARP inhibition largely relies on disrupted m6A modification of HR and apoptotic genes, counteracting PARP inhibitor (PARPi) resistance in patient-derived xenograft models. Our study revealed a widespread active cross-talk between BRD4-dependent epigenetic and MTC-mediated epitranscriptomic networks, which provides a unique therapeutic vulnerability that can be leveraged in combined DNA repair-targeted therapy.


Assuntos
Antineoplásicos , Proteínas que Contêm Bromodomínio , Proteínas Nucleares , Humanos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Reparo do DNA , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Epigênese Genética , Proteínas que Contêm Bromodomínio/genética , Proteínas que Contêm Bromodomínio/metabolismo , Animais
2.
Phys Rev Lett ; 132(13): 130603, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613293

RESUMO

In the quest to build general-purpose photonic quantum computers, fusion-based quantum computation has risen to prominence as a promising strategy. This model allows a ballistic construction of large cluster states which are universal for quantum computation, in a scalable and loss-tolerant way without feed forward, by fusing many small n-photon entangled resource states. However, a key obstacle to this architecture lies in efficiently generating the required essential resource states on photonic chips. One such critical seed state that has not yet been achieved is the heralded three-photon Greenberger-Horne-Zeilinger (3-GHZ) state. Here, we address this elementary resource gap, by reporting the first experimental realization of a heralded 3-GHZ state. Our implementation employs a low-loss and fully programmable photonic chip that manipulates six indistinguishable single photons of wavelengths in the telecommunication regime. Conditional on the heralding detection, we obtain the desired 3-GHZ state with a fidelity 0.573±0.024. Our Letter marks an important step for the future fault-tolerant photonic quantum computing, leading to the acceleration of building a large-scale optical quantum computer.

3.
Phys Rev Lett ; 130(7): 070801, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36867807

RESUMO

Quantum metrology employs quantum resources to enhance the measurement sensitivity beyond that can be achieved classically. While multiphoton entangled N00N states can in principle beat the shot-noise limit and reach the Heisenberg limit, high N00N states are difficult to prepare and fragile to photon loss which hinders them from reaching unconditional quantum metrological advantages. Here, we combine the idea of unconventional nonlinear interferometers and stimulated emission of squeezed light, previously developed for the photonic quantum computer Jiuzhang, to propose and realize a new scheme that achieves a scalable, unconditional, and robust quantum metrological advantage. We observe a 5.8(1)-fold enhancement above the shot-noise limit in the Fisher information extracted per photon, without discounting for photon loss and imperfections, which outperforms ideal 5-N00N states. The Heisenberg-limited scaling, the robustness to external photon loss, and the ease-of-use of our method make it applicable in practical quantum metrology at a low photon flux regime.

4.
Phys Rev Lett ; 131(15): 150601, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897783

RESUMO

We report new Gaussian boson sampling experiments with pseudo-photon-number-resolving detection, which register up to 255 photon-click events. We consider partial photon distinguishability and develop a more complete model for the characterization of the noisy Gaussian boson sampling. In the quantum computational advantage regime, we use Bayesian tests and correlation function analysis to validate the samples against all current classical spoofing mockups. Estimating with the best classical algorithms to date, generating a single ideal sample from the same distribution on the supercomputer Frontier would take ∼600 yr using exact methods, whereas our quantum computer, Jiǔzhang 3.0, takes only 1.27 µs to produce a sample. Generating the hardest sample from the experiment using an exact algorithm would take Frontier∼3.1×10^{10} yr.

5.
Langmuir ; 39(36): 12807-12816, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37625097

RESUMO

A multifunctional nanopesticide delivery system is considered to be a novel and efficient tool for controlling pests in modern agriculture. In this study, a mesoporous silica nanosheet (H-MSN) carrier for intelligent delivery of pesticides was prepared by the sol-gel method. The prepared H-MSN carrier had obvious hexagonal flat structure, with a specific surface area of 759.9 m2/g, a transverse diameter of about 340 nm, a thickness of about 80 nm, and regular channels being perpendicular to the plane. Polyethylene glycol diacrylate (PEGDA) and sulfhydryl-modified polyethylenimide (PEI-SH) were used to block the insecticide after loading the insecticide imidacloprid (IMI). The introduction of hydrophilic PEI-SH/PEGDA greatly improved the leaf wettability and adhesion ability of H-MSN. The retention amount of IMI@H-MSN@PEI-SH/PEGDA on cucumber and cabbage leaves was up to 46.0 mg/cm2 and 19.0 mg/cm2, respectively. IMI@H-MSN@PEI-SH/PEGDA showed pH- and GSH-responsive release. Compared with pure IMI, IMI entrapped in MSN carriers has favorable biocompatibility and antiphotolytic properties.


Assuntos
Inseticidas , Praguicidas , Neonicotinoides
6.
J Comput Chem ; 43(4): 289-302, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34862652

RESUMO

Buchwald-Hartwig amination reaction catalyzed by palladium plays an important role in drug synthesis. In the last few years, machine learning-assisted strategies emerged and quickly gained attention. In this article, an importance and relevance-based integrated feature screening method is proposed to effectively filter high-dimensional feature descriptor data. Then, a regularized machine learning boosting tree model, eXtreme Gradient Boosting, is introduced to intelligently predict reaction performance in multidimensional chemistry space. Furthermore, convergence, interpretability, generalization, and the internal association between reaction conditions and yields are excavated, which provides intelligent assistance for the optimal design of coupling reaction system and evaluating the reaction conditions. Compared with recently published results, the proposed method requires fewer feature descriptors, takes less time, and achieves more accurate prediction accuracy.


Assuntos
Aminas/síntese química , Aminação , Aminas/química , Catálise , Aprendizado de Máquina , Paládio
7.
Mikrochim Acta ; 189(10): 376, 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-36074274

RESUMO

A novel near-infrared (NIR) light-triggered smart nanoplatform has been developed for cancer targeting and imaging-guided combined photothermal-chemo treatment. Notably, Ag2S has a dual function of photothermal therapy and fluorescence imaging, which greatly simplifies the structure of the system. It can emit fluorescence at 820 nm under an excitation wavelength of 560 nm. The phase-change molecule of 1-tetradecanol (TD) is introduced as a temperature-sensitive gatekeeper to provide the nanocarrier with controlled release capability of doxorubicin (DOX). The nanocarrier (HAg2S@mSiO2-TD/DOX) shows a high drug loading capacity of 26.3% and exhibits an apparent NIR-responsive DOX release property. Under NIR irradiation, the photothermal effect of HAg2S nanocores facilitated the release of DOX through the melting of TD. The cytotoxicity test shows that the nanocarriers have good biocompatibility. As the same time, the synergistic combination leads to a better cancer inhibition effect than individual therapy alone in vitro. Cell uptake tests indicate that the carriers have excellent fluorescence imaging ability and high cellular uptake for HepG2 cells. This work provides a new strategy for the fabrication of smart nanocarriers with simple structures for fluorescence-mediated combination cancer therapy. Fabrication of a smart drug delivery system based on hollow Ag2S@mSiO2 nanoparticles for fluorescence-guided synergistic photothermal chemotherapy.


Assuntos
Nanopartículas , Neoplasias , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Fluorescência , Humanos , Nanopartículas/química , Neoplasias/tratamento farmacológico
8.
Phys Rev Lett ; 127(23): 230503, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34936806

RESUMO

Quantum self-testing is a device-independent way to certify quantum states and measurements using only the input-output statistics, with minimal assumptions about the quantum devices. Because of the high demand on tolerable noise, however, experimental self-testing was limited to two-photon systems. Here, we demonstrate the first robust self-testing for multiphoton genuinely entangled quantum states. We prepare two examples of four-photon graph states, the Greenberger-Horne-Zeilinger states with a fidelity of 0.957(2) and the linear cluster states with a fidelity of 0.945(2). Based on the observed input-output statistics, we certify the genuine four-photon entanglement and further estimate their qualities with respect to realistic noise in a device-independent manner.

9.
Phys Rev Lett ; 127(18): 180502, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34767431

RESUMO

We report phase-programmable Gaussian boson sampling (GBS) which produces up to 113 photon detection events out of a 144-mode photonic circuit. A new high-brightness and scalable quantum light source is developed, exploring the idea of stimulated emission of squeezed photons, which has simultaneously near-unity purity and efficiency. This GBS is programmable by tuning the phase of the input squeezed states. The obtained samples are efficiently validated by inferring from computationally friendly subsystems, which rules out hypotheses including distinguishable photons and thermal states. We show that our GBS experiment passes a nonclassicality test based on inequality constraints, and we reveal nontrivial genuine high-order correlations in the GBS samples, which are evidence of robustness against possible classical simulation schemes. This photonic quantum computer, Jiuzhang 2.0, yields a Hilbert space dimension up to ∼10^{43}, and a sampling rate ∼10^{24} faster than using brute-force simulation on classical supercomputers.

10.
Nano Lett ; 20(1): 152-157, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31841348

RESUMO

We demonstrate fourth-order quantum beat between sunlight and single photons from a quantum dot. With a fast time-resolved detection system, we observed high-visibility quantum beat between the independent photons of different frequencies from the two astronomically separated light sources. The temporal dynamics of the beat oscillation indicate the coherent behavior of the interfering photons, and the raw visibility of two-photon interference shows violation of the classical limit with a frequency mismatch of three-times the line width.

11.
Phys Rev Lett ; 125(21): 210502, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33274970

RESUMO

Quantum no-cloning, the impossibility of perfectly cloning an arbitrary unknown quantum state, is one of the most fundamental limitations due to the laws of quantum mechanics, which underpin the physical security of quantum key distribution. Quantum physics does allow, however, approximate cloning with either imperfect state fidelity and/or probabilistic success. Whereas approximate quantum cloning of single-particle states has been tested previously, experimental cloning of quantum entanglement-a highly nonclassical correlation-remained unexplored. Based on a multiphoton linear optics platform, we demonstrate quantum cloning of two-photon entangled states for the first time. Remarkably our results show that one maximally entangled photon pair can be broadcast into two entangled pairs, both with state fidelities above 50%. Our results are a key step towards cloning of complex quantum systems, and are likely to provide new insights into quantum entanglement.

12.
Phys Rev Lett ; 123(7): 070505, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31491117

RESUMO

Quantum teleportation allows a "disembodied" transmission of unknown quantum states between distant quantum systems. Yet, all teleportation experiments to date were limited to a two-dimensional subspace of quantized multiple levels of the quantum systems. Here, we propose a scheme for teleportation of arbitrarily high-dimensional photonic quantum states and demonstrate an example of teleporting a qutrit. Measurements over a complete set of 12 qutrit states in mutually unbiased bases yield a teleportation fidelity of 0.75(1), which is well above both the optimal single-copy qutrit state-estimation limit of 1/2 and maximal qubit-qutrit overlap of 2/3, thus confirming a genuine and nonclassical three-dimensional teleportation. Our work will enable advanced quantum technologies in high dimensions, since teleportation plays a central role in quantum repeaters and quantum networks.

13.
Phys Rev Lett ; 123(8): 080401, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31491194

RESUMO

We report an experiment to test quantum interference, entanglement, and nonlocality using two dissimilar photon sources, the Sun and a semiconductor quantum dot on the Earth, which are separated by ∼150 million kilometers. By making the otherwise vastly distinct photons indistinguishable in all degrees of freedom, we observe time-resolved two-photon quantum interference with a raw visibility of 0.796(17), well above the 0.5 classical limit, providing unambiguous evidence of the quantum nature of thermal light. Further, using the photons with no common history, we demonstrate postselected two-photon entanglement with a state fidelity of 0.826(24) and a violation of Bell inequality by 2.20(6). The experiment can be further extended to a larger scale using photons from distant stars and open a new route to quantum optics experiments at an astronomical scale.

14.
Phys Rev Lett ; 121(25): 250505, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30608840

RESUMO

Entangled-photon sources with simultaneously near-unity heralding efficiency and indistinguishability are the fundamental elements for scalable photonic quantum technologies. We design and realize a degenerate telecommunication wavelength entangled-photon source from an ultrafast pulsed laser pumped spontaneous parametric down-conversion (SPDC), which shows simultaneously 97% heralding efficiency and 96% indistinguishability between independent single photons without narrow-band filtering. Such a beamlike and frequency-uncorrelated SPDC source allows generation of the first 12-photon genuine entanglement with a state fidelity of 0.572±0.024. We further demonstrate a blueprint of scalable scattershot boson sampling using 12 SPDC sources and a 12×12 mode interferometer for three-, four-, and five-boson sampling, which yields count rates more than 4 orders of magnitude higher than all previous SPDC experiments.

15.
Endocr Res ; 42(3): 180-190, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28281841

RESUMO

Hepatic glucokinase (GK) expression and activity are decreased in type 2 diabetes mellitus (T2DM), and glycogen synthase kinase-3 (GSK-3) inhibits the synthesis of GK. In hepatocytes, the activation of the protein kinase B (PKB/AKT) signaling pathway enhances GK expression and inhibits the phosphorylation of GSK-3ß. The dysfunction of certain long noncoding RNAs (lncRNAs) has been associated with a variety of diseases. AIMS: This study explored the effects of the lncRNA NONRATT021972 small interfering RNA (siRNA) on the dysfunction of hepatic GK through AKT signaling in T2DM rats. METHODS: Livers from type 2 diabetic rats and hepatocytes cultured in high glucose and high fatty acid media were studied. The changes in expression of AKT, GK and GSK 3ß were detected by western blotting or RT-PCR. The application of bioinformatics technology (CatRAPID) was used to identify the targets of NONRATT021972 RNA. RESULTS: We found that lncRNA NONRATT021972 levels in the liver were increased in type 2 diabetic rats, and the increase was associated with an increase in the blood glucose levels. The NONRATT021972 siRNA enhanced phospho-AKT (p-AKT) levels, GK expression and hepatic glycogen synthesis. This siRNA also reduced phospho-glycogen synthase kinase-3ß (p-GSK-3ß) levels and hyperglycemia in T2DM rats, as well as in hepatocytes cultured in high glucose media with fatty acids. CatRAPID predicted that there was the interaction between NONRATT021972 and p-AKT. CONCLUSIONS: LncRNA NONRATT021972 siRNA may have beneficial effects on T2DM.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glucoquinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/metabolismo , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/fisiologia , Animais , Masculino , Ratos , Ratos Sprague-Dawley
16.
Sheng Li Xue Bao ; 68(1): 12-8, 2016 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-26915317

RESUMO

The aim of the present study was to investigate the effects of ketamine, imipramine, and ketamine plus imipramine on chronic depression-like behaviors of Wistar Kyoto (WKY) rats and underlying mechanism. Six-week-old Wistar rats were used as normal control. WKY rats, depression model animal, were injected intraperitoneally with ketamine (1 week, replaced with saline in 2(nd) week), imipramine (2 weeks), or ketamine in combination with imipramine. The depression-like behaviors were assessed by sucrose preference and forced swimming tests. Protein expressions of ß form of calcium/calmodulin-dependent protein kinase type II (ßCaMKII) and membrane fraction of glutamate receptor 1 (GluR1) were measured in corresponding brain tissue with Western blot. The results showed that, compared with Wistar rats, WKY rats exhibited decreased sucrose preference and extended immobility time. Ketamine alone did not affect depression-like behaviors of WKY, whereas imipramine or its combination with ketamine could significantly decrease the immobility time. Compared with Wistar rats, WKY rats showed up-regulated levels of ßCaMKII and membrane GluR1 protein expressions in habenula, and down-regulated level of membrane GluR1 protein expressions in the prefrontal cortex. Imipramine or its combination with ketamine could reverse these changes of protein expressions in WKY rats. There was no difference in reversing effect between imipramine and its combination with ketamine. Ketamine alone did not affect the ßCaMKII and membrane GluR1 protein expressions in the habenula, but increased membrane GluR1 protein expression in the prefrontal cortex of WKY rats. These results suggest 2-week imipramine treatment significantly improves depressive behavior in WKY rats; however, the addition of ketamine in the first week fails to enhance the effect of imipramine. The underlying mechanisms of imipramine's anti-depressive effect may be associated with the down-regulation of ßCaMKII and membrane GluR1 in the habenula, as well as the up-regulation of membrane GluR1 in the prefrontal cortex.


Assuntos
Depressão , Animais , Encéfalo , Transtorno Depressivo , Modelos Animais de Doenças , Regulação para Baixo , Imipramina , Ketamina , Masculino , Ratos , Ratos Endogâmicos WKY , Natação , Regulação para Cima
17.
Purinergic Signal ; 11(2): 161-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25527178

RESUMO

Irritable bowel syndrome (IBS) and inflammatory bowel disease often display visceral hypersensitivity. Visceral nociceptors after inflammatory stimulation generate afferent nerve impulses through dorsal root ganglia (DRG) transmitting to the central nervous system. ATP and its activated-purinergic 2X7 (P2X7) receptor play an important role in the transmission of nociceptive signal. Purinergic signaling is involved in the sensory transmission of visceral pain. Moxibustion is a therapy applying ignited mugwort directly or indirectly at acupuncture points or other specific parts of the body to treat diseases. Heat-sensitive acupoints are the corresponding points extremely sensitive to moxa heat in disease conditions. In this study, we aimed to investigate the relationship between the analgesic effect of moxibustion on a heat-sensitive acupoint "Dachangshu" and the expression levels of P2X7 receptor in rat DRG after chronic inflammatory stimulation of colorectal distension. Heat-sensitive moxibustion at Dachangshu acupoint inhibited the nociceptive signal transmission by decreasing the upregulated expression levels of P2X7 mRNA and protein in DRG induced by visceral pain, and reversed the abnormal expression of glial fibrillary acidic protein (GFAP, a marker of satellite glial cells) in DRG. Consequently, abdominal withdrawal reflex (AWR) score in a visceral pain model was reduced, and the pain threshold was elevated. Therefore, heat-sensitive moxibustion at Dachangshu acupoint can produce a therapeutic effect on IBS via inhibiting the nociceptive transmission mediated by upregulated P2X7 receptor.


Assuntos
Gânglios Espinais/metabolismo , Hiperalgesia/metabolismo , Moxibustão , Receptores Purinérgicos P2X7/metabolismo , Animais , Modelos Animais de Doenças , Síndrome do Intestino Irritável/metabolismo , Masculino , Moxibustão/métodos , Ratos Sprague-Dawley
18.
Clin Exp Pharmacol Physiol ; 42(7): 780-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25951228

RESUMO

Neuropathic pain is a common and severely disabling state that affects millions of people worldwide. The P2X3 receptor plays a crucial role in facilitating pain transmission. Intermedin (IMD), which is also known as adrenomedullin 2 (AMD2) is a newly discovered hormone that is a member of the calcitonin/calcitonin gene-related peptide family. The present research investigates the effects of IMD on pain transmission in neuropathic pain states as mediated by P2X3 receptors in dorsal root ganglia (DRG). Chronic constriction injury (CCI) rats were used as the neuropathic pain model. Adult male Sprague-Dawley rats were randomly assigned to five groups as follows: blank control group (Control), sham operation group (Sham), CCI rats treated with saline group (CCI+NS), CCI rats treated with IMD1-53 group (CCI+IMD1-53 ), and CCI rats treated with IMD inhibitor IMD14-47 group (CCI+IMD14-47 ). The mechanical withdrawal threshold (MWT) was tested by the von Frey method, and the thermal withdrawal latency (TWL) was tested via automatic thermal stimulus instruments. Changes in the expression of P2X3 receptors and IMD in CCI rat L4/L5 DRG were detected using immunohistochemistry, reverse transcription-polymerase chain reaction, and Western blotting. After treatment with intrathecal injection (i.t.), mechanical and thermal hyperalgesia in the CCI+IMD1-53 group was maintained, but MWT and TWL in the CCI+IMD14-47 groups increased. The expression levels of P2X3 receptors and IMD in L4/L5 DRG in the CCI+NS and CCI+IMD1-53 groups were significantly increased compared with those in the Control group or the Sham group. After application of IMD14-47 in CCI rats, there was a decrease in the expression levels of P2X3 receptors and IMD in L4/L5 DRG. The phosphorylation of p38 and ERK1/2 in L4/L5 DRG in the CCI+NS group and the CCI+IMD1-53 group was stronger than that in the Control group or the Sham group; however, the phosphorylation of p38 and ERK1/2 in the CCI+IMD14-47 group was much lower than that in the CCI+NS group or the CCI+IMD1-53 group. Our findings indicate that IMD might increase the sensitization effects of IMD on P2X3 receptors to alleviate chronic neuropathic pain injury. The IMD agonist IMD1-53 might enhance nociceptive responses mediated by P2X3 receptors in neuropathic pain, and the IMD inhibitor IMD14-47 could inhibit the sensitization of the P2X3 receptor in chronic neuropathic pain injury.


Assuntos
Adrenomedulina/farmacologia , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/patologia , Neuralgia/tratamento farmacológico , Neuralgia/patologia , Adrenomedulina/metabolismo , Adrenomedulina/uso terapêutico , Animais , Constrição , Regulação da Expressão Gênica/efeitos dos fármacos , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Masculino , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neuralgia/etiologia , Neuralgia/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores Purinérgicos P2X3/genética , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
19.
J Cell Mol Med ; 18(12): 2367-71, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25312986

RESUMO

Neuropathic pain is a very common complication in diabetes mellitus (DM), and treatment for it is limited. As DM is becoming a global epidemic it is important to understand and treat this problem. The mechanisms of diabetic neuropathic pain are largely obscure. Recent studies have shown that glial cells are important for a variety of neuropathic pain types, and we investigated what are the changes that satellite glial cells (SGCs) in dorsal root ganglia undergo in a DM type 1 model, induced by streptozotocin (STZ) in mice and rats. We carried out immunohistochemical studies to learn about changes in the activation marker glial fibrillary acidic protein (GFAP) in SGCs. We found that after STZ-treatment the number of neurons surrounded with GFAP-positive SGCs in dorsal root ganglia increased 4-fold in mice and 5-fold in rats. Western blotting for GFAP, which was done only on rats because of the larger size of the ganglia, showed an increase of about 2-fold in STZ-treated rats, supporting the immunohistochemical results. These results indicate for the first time that SGCs are activated in rodent models of DM1. As SGC activation appears to contribute to chronic pain, these results suggest that SGCs may participate in the generation and maintenance of diabetic neuropathic pain, and can serve as a potential therapeutic target.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Gânglios Espinais/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Neuroglia/metabolismo , Animais , Western Blotting , Diabetes Mellitus Tipo 1/complicações , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/metabolismo , Feminino , Gânglios Espinais/citologia , Imuno-Histoquímica , Masculino , Camundongos Endogâmicos C57BL , Neuralgia/diagnóstico , Neuralgia/etiologia , Medição da Dor/métodos , Limiar da Dor , Ratos Sprague-Dawley , Fatores de Tempo
20.
Neural Plast ; 2014: 786985, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24778886

RESUMO

Renshaw recurrent inhibition (RI) plays an important gated role in spinal motion circuit. Peripheral nerve injury is a common disease in clinic. Our current research was designed to investigate the change of the recurrent inhibitory function in the spinal cord after the peripheral nerve crush injury in neonatal rat. Sciatic nerve crush was performed on 5-day-old rat puppies and the recurrent inhibition between lateral gastrocnemius-soleus (LG-S) and medial gastrocnemius (MG) motor pools was assessed by conditioning monosynaptic reflexes (MSR) elicited from the sectioned dorsal roots and recorded either from the LG-S and MG nerves by antidromic stimulation of the synergist muscle nerve. Our results demonstrated that the MSR recorded from both LG-S or MG nerves had larger amplitude and longer latency after neonatal sciatic nerve crush. The RI in both LG-S and MG motoneuron pools was significantly reduced to virtual loss (15-20% of the normal RI size) even after a long recovery period upto 30 weeks after nerve crush. Further, the degree of the RI reduction after tibial nerve crush was much less than that after sciatic nerve crush indicatig that the neuron-muscle disconnection time is vital to the recovery of the spinal neuronal circuit function during reinnervation. In addition, sciatic nerve crush injury did not cause any spinal motor neuron loss but severally damaged peripheral muscle structure and function. In conclusion, our results suggest that peripheral nerve injury during neonatal early development period would cause a more sever spinal cord inhibitory circuit damage, particularly to the Renshaw recurrent inhibition pathway, which might be the target of neuroregeneration therapy.


Assuntos
Animais Recém-Nascidos/fisiologia , Compressão Nervosa , Inibição Neural/fisiologia , Nervo Isquiático/patologia , Animais , Estimulação Elétrica , Fenômenos Eletrofisiológicos/fisiologia , Membro Posterior/inervação , Peroxidase do Rábano Silvestre , Masculino , Neurônios Motores/fisiologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Regeneração Nervosa/fisiologia , Ratos , Ratos Wistar , Reflexo Monosináptico/fisiologia , Nervo Tibial/fisiologia
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