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Connexin43 (Cx43) is a major gap junction protein in glial cells. Mutations have been found in the gap-junction alpha 1 gene encoding Cx43 in glaucomatous human retinas, suggestive of the involvement of Cx43 in the pathogenesis of glaucoma. However, how Cx43 is involved in glaucoma is still unknown. We showed that increased intraocular pressure in a glaucoma mouse model of chronic ocular hypertension (COH) downregulated Cx43, which was mainly expressed in retinal astrocytes. Astrocytes in the optic nerve head where they gather and wrap the axons (optic nerve) of retinal ganglion cells (RGCs) were activated earlier than neurons in COH retinas and the alterations in astrocytes plasticity in the optic nerve caused a reduction in Cx43 expression. A time course showed that reductions of Cx43 expression were correlated with the activation of Rac1, a member of the Rho family. Co-immunoprecipitation assays showed that active Rac1, or the downstream signaling effector PAK1, negatively regulated Cx43 expression, Cx43 hemichannel opening and astrocyte activation. Pharmacological inhibition of Rac1 stimulated Cx43 hemichannel opening and ATP release, and astrocytes were identified to be one of the main sources of ATP. Furthermore, conditional knockout of Rac1 in astrocytes enhanced Cx43 expression and ATP release, and promoted RGC survival by upregulating the adenosine A3 receptor in RGCs. Our study provides new insight into the relationship between Cx43 and glaucoma, and suggests that regulating the interaction between astrocytes and RGCs via the Rac1/PAK1/Cx43/ATP pathway may be used as part of a therapeutic strategy for managing glaucoma.
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Glaucoma , Hipertensão Ocular , Animais , Humanos , Camundongos , Trifosfato de Adenosina/metabolismo , Astrócitos/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Glaucoma/metabolismo , Glaucoma/patologia , Hipertensão Ocular/metabolismo , Quinases Ativadas por p21/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Células Ganglionares da Retina/metabolismoRESUMO
BACKGROUND: Glaucoma, the leading cause of irreversible blindness, is a retinal neurodegenerative disease, which results from progressive apoptotic death of retinal ganglion cells (RGCs). Although the mechanisms underlying RGC apoptosis in glaucoma are extremely complicated, an abnormal cross-talk between retinal glial cells and RGCs is generally thought to be involved. However, how interaction of Müller cells and microglia, two types of glial cells, contributes to RGC injury is largely unknown. METHODS: A mouse chronic ocular hypertension (COH) experimental glaucoma model was produced. Western blotting, immunofluorescence, quantitative real-time polymerase chain reaction (q-PCR), transwell co-culture of glial cells, flow cytometry assay, ELISA, Ca2+ image, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) techniques were employed to investigate the interaction of Müller cells and microglia, and its underlying mechanisms in COH retina. RESULTS: We first showed that Müller cell activation in mice with COH induced microglia activation through the ATP/P2X7 receptor pathway. The activation of microglia resulted in a significant increase in mRNA and protein levels of pro-inflammatory factors, such as tumor necrosis factor-α and interleukin-6. These inflammatory factors in turn caused the up-regulation of mRNA expression of pro-inflammatory factors in Müller cells through a positive feedback manner. CONCLUSIONS: These findings provide robust evidence, for the first time, that retinal inflammatory response may be aggravated by an interplay between activated two types of glial cells. These results also suggest that to reduce the interplay between Müller cells and microglia could be a potential effective strategy for preventing the loss of RGCs in glaucoma.
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Células Ependimogliais/patologia , Glaucoma/complicações , Microglia/patologia , Retinite/etiologia , Retinite/patologia , Trifosfato de Adenosina/fisiologia , Animais , Técnicas de Cocultura , Citocinas/metabolismo , Ativação de Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Hipertensão Ocular/complicações , Receptores Purinérgicos P2X7 , Células Ganglionares da Retina/patologia , Transdução de SinaisRESUMO
Calpains are calcium-dependent, cytosolic proteinases active at neutral pH. They do not degrade but cleave substrates at limited sites. Calpains are implicated in various pathologies, such as ischemia, injuries, muscular dystrophy, and neurodegeneration. Despite so, the physiological function of calpains remains to be clearly defined. Using the neuromuscular junction of Drosophila of both sexes as a model, we performed RNAi screening and uncovered that calpains negatively regulated protein levels of the glutamate receptor GluRIIA but not GluRIIB. We then showed that calpains enrich at the postsynaptic area, and the calcium-dependent activation of calpains induced cleavage of GluRIIA at Q788 of its C terminus. Further genetic and biochemical experiments revealed that different calpains genetically and physically interact to form a protein complex. The protein complex was required for the proteinase activation to downregulate GluRIIA. Our data provide a novel insight into the mechanisms by which different calpains act together as a complex to specifically control GluRIIA levels and consequently synaptic function.SIGNIFICANCE STATEMENT Calpain has been implicated in neural insults and neurodegeneration. However, the physiological function of calpains in the nervous system remains to be defined. Here, we show that calpain enriches at the postsynaptic area and negatively and specifically regulates GluRIIA, but not IIB, level during development. Calcium-dependent activation of calpain cleaves GluRIIA at Q788 of its C terminus. Different calpains constitute an active protease complex to cleave its target. This study reveals a critical role of calpains during development to specifically cleave GluRIIA at synapses and consequently regulate synaptic function.
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Calpaína/genética , Calpaína/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Junção Neuromuscular/genética , Junção Neuromuscular/metabolismo , Receptores Ionotrópicos de Glutamato/genética , Receptores Ionotrópicos de Glutamato/metabolismo , Animais , Sinalização do Cálcio/genética , Regulação para Baixo/genética , Feminino , Imuno-Histoquímica , Masculino , Músculos/metabolismo , Optogenética , Peptídeo Hidrolases/metabolismo , Interferência de RNA , Especificidade por Substrato , Sinapses/genética , Sinapses/metabolismo , Sinapses/fisiologiaRESUMO
Altered expression of the E3 ubiquitin ligase UBE3A, which is involved in protein degradation through the proteasome-mediated pathway, is associated with neurodevelopmental and behavioral defects observed in Angelman syndrome (AS) and autism. However, little is known about the neuronal function of UBE3A and the pathogenesis of UBE3A-associated disorders. To understand the in vivo function of UBE3A in the nervous system, we generated multiple mutations of ube3a, the Drosophila ortholog of UBE3A. We found a significantly increased number of total boutons and satellite boutons in conjunction with compromised endocytosis in the neuromuscular junctions (NMJs) of ube3a mutants compared to the wild type. Genetic and biochemical analysis showed upregulation of bone morphogenetic protein (BMP) signaling in the nervous system of ube3a mutants. An immunochemical study revealed a specific increase in the protein level of Thickveins (Tkv), a type I BMP receptor, but not other BMP receptors Wishful thinking (Wit) and Saxophone (Sax), in ube3a mutants. Ube3a was associated with and specifically ubiquitinated lysine 227 within the cytoplasmic tail of Tkv, and promoted its proteasomal degradation in Schneider 2 cells. Negative regulation of Tkv by Ube3a was conserved in mammalian cells. These results reveal a critical role for Ube3a in regulating NMJ synapse development by repressing BMP signaling. This study sheds new light onto the neuronal functions of UBE3A and provides novel perspectives for understanding the pathogenesis of UBE3A-associated disorders.
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Síndrome de Angelman/genética , Proteínas de Drosophila/biossíntese , Proteínas de Drosophila/genética , Neurônios/metabolismo , Proteínas Serina-Treonina Quinases/biossíntese , Receptores de Superfície Celular/biossíntese , Ubiquitina-Proteína Ligases/genética , Síndrome de Angelman/patologia , Animais , Proteínas Morfogenéticas Ósseas/biossíntese , Proteínas Morfogenéticas Ósseas/genética , Modelos Animais de Doenças , Drosophila/genética , Endocitose/genética , Regulação da Expressão Gênica/genética , Humanos , Junção Neuromuscular/genética , Junção Neuromuscular/patologia , Neurônios/patologia , Proteínas Serina-Treonina Quinases/genética , Receptores de Superfície Celular/genética , Transdução de Sinais , Sinapses/genética , Ubiquitina-Proteína Ligases/biossínteseRESUMO
OBJECTIVE: In this study, the transcriptome profile of cow experiencing miscarriage during peri-implantation was investigated. METHODS: Total transcriptomes were checked by RNA sequencing, and the analyzed by bioinformatics methods, the differentially expressed genes (DEGs) were analysed with hierarchical clustering and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis. RESULTS: The results suggested that serum progesterone levels were significantly decreased in cows that miscarried as compared to the pregnant cows at 18, 21, 33, 39, and 51 days after artificial insemination. The RNA sequencing results suggested that 32, 176, 5, 10, and 2 DEGs were identified in the pregnant cows and miscarried cows at 18, 21, 33, 39, and 51 d after artificial insemination. And 15, 101, 1, 2, and 2 DEGs were upregulated, and 17, 74, 4, and 8 DEGs were downregulated in the cows in the pregnant and miscarriage groups, respectively at 18, 21, 33, and 39, but no gene was downregulated at 51 d after artificial insemination. These DEGs were distributed to 13, 20, 3, 6, and 20 pathways, and some pathway essential for pregnancy, such as cell adhesion molecules, tumor necrosis factor signaling pathway and PI3K-Akt signaling pathway. CONCLUSION: This analysis has identified several genes and related pathways crucial for pregnancy and miscarriage in cows, as well as these genes supply molecular markers to predict the miscarriage in cows.
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BACKGROUND: Morphine and oxycodone are considered as wide-spreadly used opioids for moderate/severe cancer pain. However, debate exists about the evidence regarding their relative tolerability and underlying results. METHODS: A systematic search of online electronic databases, including PubMed, Embase, Cochrane library updated on October 2017 were conducted. The meta-analysis was performed including the studies that were designed as randomized controlled trials. RESULTS: In total, seven randomized clinical trials met our inclusion criteria. No statistical differences in analgesic effect between oxycodone and morphine were observed. Both the pooled analysis of API (MD =0.01, 95% CI -0.22 - 0.23; p = 0.96) and WPI (MD = - 0.05, 95% CI -0.21 - 0.30; p = 0.72) demonstrated clinical non-inferiority of the efficacy of morphine compared with oxycodone, respectively. Additionally, no significant difference in PRR response was observed in either oxycodone or morphine that were used in patients (MD =0.99, 95% CI -0.88 - 1.11; p = 0.87). With the pooled result of AEs indicating the comparable safety profiles between the 2 treatment groups, the meta-analysis on the nausea (OR = 1.20, 95% CI 0.90-1.59; p = 0.22), vomiting (OR = 1.33, 95% CI 0.75-2.38; p = 0.33), somnolence (OR = 1.35, 95% CI 0.95-1.93; p = 0.10), diarrhea (OR = 1.01, 95% CI 0.60-1,67; p = 0.98), and constipation (OR = 1.04, 95% CI 0.77-1.41; p = 0.79) was conducted, respectively. CONCLUSIONS: In the current study, no remarkable difference was identified either in analgesic efficacy or in tolerability of oxycodone and morphine as the first-line therapy for patients with moderate to severe cancer pain. Thus, no sufficient clinical evidence on the superior effects of oxycodone to morphine was provided in this experimental hypothesis.
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Analgésicos Opioides/administração & dosagem , Dor do Câncer/tratamento farmacológico , Morfina/administração & dosagem , Oxicodona/administração & dosagem , Dor do Câncer/diagnóstico , Dor do Câncer/epidemiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Resultado do TratamentoRESUMO
After publication of this article [1], the authors noted that the corresponding email address is incorrect.
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Synaptic connections must be precisely controlled to ensure proper neural circuit formation. In Drosophila melanogaster, bone morphogenetic protein (BMP) promotes growth of the neuromuscular junction (NMJ) by binding and activating the BMP ligand receptors wishful thinking (Wit) and thickveins (Tkv) expressed in motor neurons. We report here that an evolutionally conserved, previously uncharacterized member of the S6 kinase (S6K) family S6K like (S6KL) acts as a negative regulator of BMP signaling. S6KL null mutants were viable and fertile but exhibited more satellite boutons, fewer and larger synaptic vesicles, larger spontaneous miniature excitatory junctional potential (mEJP) amplitudes, and reduced synaptic endocytosis at the NMJ terminals. Reducing the gene dose by half of tkv in S6KL mutant background reversed the NMJ overgrowth phenotype. The NMJ phenotypes of S6KL mutants were accompanied by an elevated level of Tkv protein and phosphorylated Mad, an effector of the BMP signaling pathway, in the nervous system. In addition, Tkv physically interacted with S6KL in cultured S2 cells. Furthermore, knockdown of S6KL enhanced Tkv expression, while S6KL overexpression downregulated Tkv in cultured S2 cells. This latter effect was blocked by the proteasome inhibitor MG132. Our results together demonstrate for the first time that S6KL regulates synaptic development and function by facilitating proteasomal degradation of the BMP receptor Tkv.
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Receptores de Proteínas Morfogenéticas Ósseas/biossíntese , Proteínas de Drosophila/genética , Junção Neuromuscular/crescimento & desenvolvimento , Proteínas Serina-Treonina Quinases/genética , Receptores de Superfície Celular/genética , Proteínas Quinases S6 Ribossômicas/metabolismo , Animais , Animais Geneticamente Modificados , Receptores de Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Endocitose/genética , Neurônios Motores/metabolismo , Junção Neuromuscular/metabolismo , Plasticidade Neuronal/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteólise , Receptores de Superfície Celular/metabolismo , Proteínas Quinases S6 Ribossômicas/genética , Transdução de Sinais/genética , Transmissão Sináptica/genéticaRESUMO
Background: Trigeminal neuralgia (TN) is a common form of craniofacial pain, and Radiofrequency thermocoagulation (RFT) has become a commonly utilized treatment modality for TN. However, the complex anatomical configuration of the maxillofacial region and the difficulties inherent in positioning the neck in a hyperextended manner can present challenges for CT-guided punctures. Aim: The objective of this study is to assess the effectiveness and safety of 3D printed tooth-supported template(3D-PTST) guided RFT in patients who have previously undergone unsuccessful CT-guided puncture. Methods: Patients with TN undergoing RFT at the Department of Pain Medicine, PLA General Hospital, from January 2018 to January 2023, were assessed. 3D-PTST guided RFT was employed as an alternative when percutaneous puncture failed. Clinical, demographic, and follow-up data were collected. The duration of the procedure was determined by subtracting the time of anesthesia administration from the time of surgical drape removal. Pain intensity was assessed using the Numerical Rating Scale-11 scale. Treatment effects were evaluated utilizing the Barrow Neurological Institute scale. Incidences of complications related to RFA were documented. Results: Six TN patients underwent 3D-PTST guided RFT. With tooth-supported template guidance, five patients achieved therapeutic target puncture in one attempt with one CT scan. One patient required two attempts with two CT scans. Operation duration ranged from 18 to 46 mins (mean 30 mins). All completed 3D-PTST-guided RFT without difficulty, significantly improving pain symptoms. Four patients had no pain recurrence at 12, 18, 36 and 37 months follow-up, respectively. Recurrence occurred in two patients (at 1 and 13 months). No serious treatment-related complications were observed. Conclusion: 3D-PTST guided RFT is an effective, repeatable, safe, and minimally invasive treatment method for patients with TN who have failed due to difficulty in puncture.
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Background: Radiotherapy has become a standard treatment for chest tumors, but a common complication of radiotherapy is radiation lung injury. Currently, there is still a lack of effective treatment for radiation lung injury. Methods: A mouse model of radioactive lung injury (RILI) was constructed and then treated with different cycles of hydrogen inhalation. Lung function tests were performed to detect changes in lung function.HE staining was used to detect pathological changes in lung tissue. Immunofluorescence staining was used to detect the polarization of macrophages in lung tissue. Immunohistochemistry was used to detect changes in cytokine expression in lung tissues. Western Blot was used to detect the expression of proteins related to the NF-κB signalling pathway. Results: Lung function test results showed that lung function decreased in the model group and improved in the treatment group.HE staining showed that inflammatory response was evident in the model group and decreased in the treatment group. Immunohistochemistry results showed that the expression of pro-inflammatory factors was significantly higher in the model group, and the expression of pro-inflammatory factors was significantly higher in the treatment group. The expression of pro-inflammatory factors in the treatment group was significantly lower than that in the model group, and the expression of anti-inflammatory factors in the treatment group was higher than that in the model group. Immunofluorescence showed that the expression of M1 subtype macrophages was up-regulated in the model group and down-regulated in the treatment group. The expression of M2 subtype macrophages was up-regulated in the treatment group relative to the model group. Western Blot showed that P-NF-κB p65/NF-κB p65 was significantly increased in the model group, and P-NF-κB p65/NF-κB p65 was decreased in the treatment group. Conclusion: Hydrogen therapy promotes macrophage polarization from M1 to M2 subtypes by inhibiting the NF-κB signalling pathway, thereby attenuating the inflammatory response to radiation lung injury.
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Corneal neovascularization (CNV) is a common clinical finding seen in a range of eye diseases. Current therapeutic approaches to treat corneal angiogenesis, in which vascular endothelial growth factor (VEGF) A plays a central role, can cause a variety of adverse side effects. The technology of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 can edit VEGFA gene to suppress its expression. CRISPR offers a novel opportunity to treat CNV. This study shows that depletion of VEGFA with a novel CRISPR/Cas9 system inhibits proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs) in vitro. Importantly, subconjunctival injection of this dual AAV-SpCas9/sgRNA-VEGFA system is demonstrated which blocks suture-induced expression of VEGFA, CD31, and α-smooth muscle actin as well as corneal neovascularization in mice. This study has established a strong foundation for the treatment of corneal neovascularization via a gene editing approach for the first time.
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Sistemas CRISPR-Cas , Neovascularização da Córnea , Modelos Animais de Doenças , Edição de Genes , Células Endoteliais da Veia Umbilical Humana , Fator A de Crescimento do Endotélio Vascular , Neovascularização da Córnea/genética , Neovascularização da Córnea/terapia , Neovascularização da Córnea/metabolismo , Animais , Edição de Genes/métodos , Camundongos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Humanos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Sistemas CRISPR-Cas/genética , Camundongos Endogâmicos C57BL , Proliferação de Células/genéticaRESUMO
Glaucoma affects approximately 80 million individuals worldwide, a condition for which current treatment options are inadequate. The primary risk factor for glaucoma is elevated intraocular pressure. Intraocular pressure is determined by the balance between the secretion and outflow of aqueous humor. Here we show that using the RNA interference tool CasRx based on shH10 adenovirus-associated virus can reduce the expression of the aqueous humor circulation related genes Rock1 and Rock2, as well as aquaporin 1 and ß2 adrenergic receptor in female mice. This significantly reduced intraocular pressure in female mice and provided protection to the retina ganglion cells, ultimately delaying disease progression. In addition, we elucidated the mechanisms by which the knockdown of Rock1 and Rock2, or aquaporin 1 and ß2 adrenergic receptor in female mice, reduces the intraocular pressure and secures the retina ganglion cells by single-cell sequencing.
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Aquaporina 1 , Sistemas CRISPR-Cas , Glaucoma , Pressão Intraocular , Células Ganglionares da Retina , Quinases Associadas a rho , Animais , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Quinases Associadas a rho/metabolismo , Quinases Associadas a rho/genética , Feminino , Aquaporina 1/metabolismo , Aquaporina 1/genética , Camundongos , Glaucoma/genética , Glaucoma/metabolismo , Humor Aquoso/metabolismo , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Interferência de RNA , HumanosRESUMO
Keratoconus, a disorder characterized by corneal thinning and weakening, results in vision loss. Corneal crosslinking (CXL) can halt the progression of keratoconus. The development of accelerated corneal crosslinking (A-CXL) protocols to shorten the treatment time has been hampered by the rapid depletion of stromal oxygen when higher UVA intensities are used, resulting in a reduced cross-linking effect. It is therefore imperative to develop better methods to increase the oxygen concentration within the corneal stroma during the A-CXL process. Photocatalytic oxygen-generating nanomaterials are promising candidates to solve the hypoxia problem during A-CXL. Biocompatible graphitic carbon nitride (g-C3N4) quantum dots (QDs)-based oxygen self-sufficient platforms including g-C3N4 QDs and riboflavin/g-C3N4 QDs composites (RF@g-C3N4 QDs) have been developed in this study. Both display excellent photocatalytic oxygen generation ability, high reactive oxygen species (ROS) yield, and excellent biosafety. More importantly, the A-CXL effect of the g-C3N4 QDs or RF@g-C3N4 QDs composite on male New Zealand white rabbits is better than that of the riboflavin 5'-phosphate sodium (RF) A-CXL protocol under the same conditions, indicating excellent strengthening of the cornea after A-CXL treatments. These lead us to suggest the potential application of g-C3N4 QDs in A-CXL for corneal ectasias and other corneal diseases.
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Reagentes de Ligações Cruzadas , Grafite , Oxigênio , Pontos Quânticos , Riboflavina , Pontos Quânticos/química , Animais , Grafite/química , Oxigênio/metabolismo , Riboflavina/farmacologia , Coelhos , Masculino , Reagentes de Ligações Cruzadas/química , Compostos de Nitrogênio/química , Espécies Reativas de Oxigênio/metabolismo , Ceratocone/tratamento farmacológico , Ceratocone/metabolismo , Raios Ultravioleta , Córnea/efeitos dos fármacos , Córnea/metabolismo , Córnea/patologia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Substância Própria/metabolismo , Substância Própria/efeitos dos fármacosRESUMO
OBJECTIVE: To investigate the feasibility and safety of endoscopic submucosal dissection (ESD) of esophageal or gastric carcinomas under general anesthesia. SUBJECTS AND METHODS: ESD removal of esophageal or gastric carcinomas was performed in 59 patients under midazolam sedation (control group), and in 46 patients under general anesthesia (GA group). The procedural times, perioperative complications and patient's satisfaction with the procedures were recorded. RESULTS: There was no statistically significant difference in age (65 ± 12 vs. 58 ± 11), male gender (43.5 vs. 49.2%), types or location or the size of the carcinomas (30 ± 6 vs. 28 ± 7 mm) between the control and GA groups (p > 0.05). The mean procedural time in the GA group was shorter than in the control group (42.5 ± 5.5 vs. 79.0 ± 13.2 min, p = 0.01). The combined gastric perforation and postprocedural bleeding rate in the GA group was lower than in the control group, but the difference did not reach statistical significance (p = 0.06). In the GA group, all patients rated the procedural experience as satisfactory, while in the control group, 38 (64.5%) rated the experience as satisfactory (p = 0.001). CONCLUSION: ESD under general anesthesia was associated with a shorter procedure time and a high rate of patient's satisfaction with the procedures.
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Anestesia Geral/métodos , Endoscopia Gastrointestinal/métodos , Neoplasias Esofágicas/cirurgia , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diazepam/administração & dosagem , Endoscopia Gastrointestinal/efeitos adversos , Feminino , Humanos , Hipnóticos e Sedativos/administração & dosagem , Masculino , Midazolam/administração & dosagem , Pessoa de Meia-Idade , Satisfação do Paciente , Hemorragia Pós-Operatória , Propofol/administração & dosagem , Fatores de TempoRESUMO
Elevation of intraocular pressure (IOP) is a major risk factor for neurodegeneration in glaucoma. Glial cells, which play an important role in normal functioning of retinal neurons, are well involved into retinal ganglion cell (RGC) degeneration in experimental glaucoma animal models generated by elevated IOP. In response to elevated IOP, mGluR I is first activated and Kir4.1 channels are subsequently inhibited, which leads to the activation of Müller cells. Müller cell activation is followed by a complex process, including proliferation, release of inflammatory and growth factors (gliosis). Gliosis is further regulated by several factors. Activated Müller cells contribute to RGC degeneration through generating glutamate receptor-mediated excitotoxicity, releasing cytotoxic factors and inducing microglia activation. Elevated IOP activates microglia, and following morphological and functional changes, these cells, as resident immune cells in the retina, show adaptive immune responses, including an enhanced release of pro-inflammatory factors (tumor neurosis factor-α, interleukins, etc.). These ATP and Toll-like receptor-mediated responses are further regulated by heat shock proteins, CD200R, chemokine receptors, and metabotropic purinergic receptors, may aggravate RGC loss. In the optic nerve head, astrogliosis is initiated and regulated by a complex reaction process, including purines, transmitters, chemokines, growth factors and cytokines, which contributes to RGC axon injury through releasing pro-inflammatory factors and changing extracellular matrix in glaucoma. The effects of activated glial cells on RGCs are further modified by the interplay among different types of glial cells. This review is concluded by presenting an in-depth discussion of possible research directions in this field in the future.
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Glaucoma , Gliose , Animais , Gliose/patologia , Retina/metabolismo , Células Ganglionares da Retina/patologia , Neuroglia/patologia , Pressão Intraocular , Modelos Animais de DoençasRESUMO
Retinal ganglion cell apoptotic death is the main pathological characteristic of glaucoma, which is the leading cause of irreversible blindness. Disruption of Ca2+ homeostasis plays an important role in glaucoma. Voltage-gated Ca2+ channel blockers have been shown to improve vision in patients with glaucoma. However, whether and how voltage-gated Ca2+ channels are involved in retinal ganglion cell apoptotic death are largely unknown. In this study, we found that total Ca2+ current densities in retinal ganglion cells were reduced in a rat model of chronic ocular hypertension experimental glaucoma, as determined by whole-cell patch-clamp electrophysiological recordings. Further analysis showed that L-type Ca2+ currents were downregulated while T-type Ca2+ currents were upregulated at the later stage of glaucoma. Western blot assay and immunofluorescence experiments confirmed that expression of the CaV1.2 subunit of L-type Ca2+ channels was reduced and expression of the CaV3.3 subunit of T-type Ca2+ channels was increased in retinas of the chronic ocular hypertension model. Soluble tumor necrosis factor-α, an important inflammatory factor, inhibited the L-type Ca2+ current of isolated retinal ganglion cells from control rats and enhanced the T-type Ca2+ current. These changes were blocked by the tumor necrosis factor-α inhibitor XPro1595, indicating that both types of Ca2+ currents may be mediated by soluble tumor necrosis factor-α. The intracellular mitogen-activated protein kinase/extracellular signal-regulated kinase pathway and nuclear factor kappa-B signaling pathway mediate the effects of tumor necrosis factor-α. TUNEL assays revealed that mibefradil, a T-type calcium channel blocker, reduced the number of apoptotic retinal ganglion cells in the rat model of chronic ocular hypertension. These results suggest that T-type Ca2+ channels are involved in disrupted Ca2+ homeostasis and apoptosis of retinal ganglion cells in glaucoma, and application of T-type Ca2+ channel blockers, especially a specific CaV3.3 blocker, may be a potential strategy for the treatment of glaucoma.
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AIMS: To assess the repeatability and reproducibility of the ocular measurements obtained with the Suoer SW-9000 µm Plus, a new fully automatic biometer based on optical low coherence reflectometry (OLCR) biometer, and to compare them to those obtained by a swept-source optical coherence tomography (SS-OCT)-based biometer. METHODS: This prospective study consisted of 115 eyes of 115 healthy subjects. The measurements were taken by the two optical biometers in random order. The measured parameters were axial length (AL), central corneal thickness (CCT), aqueous depth (AQD), anterior chamber depth (ACD), mean keratometry (Km), lens thickness (LT) and corneal diameter (CD). To evaluate the intraobserver repeatability and interobserver reproducibility, the within-subject SD, test-retest variability, coefficient of variation (CoV) and intraclass correlation coefficient (ICC) were adopted. The Bland-Altman plot was drawn to assess the agreement. RESULTS: The repeatability and reproducibility of all parameters for the new device were excellent (ICC>0.960 and CoV<0.71%). The Bland-Altman plots showed high agreement between the OLCR-based and SS-OCT-based devices for AL, CCT, AQD, ACD, Km and LT, with narrow 95% limit of agreements (LoAs) (-0.08 mm to 0.06 mm, -15.91 µm to -1.01 µm, -0.09 mm to 0.09 mm, -0.09 mm to 0.08 mm, -0.47 D to 0.35 D, -0.05 mm to 0.16 mm, respectively) and moderate agreement for CD (95% LoA: -0.67 mm to -0.01 mm). CONCLUSIONS: The new Suoer SW-9000 µm Plus biometer showed excellent repeatability and reproducibility. All the parameters obtained by this biometer were similar to those measured by SS-OCT-based biometer.
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Precise actin regulation is essential for diverse cellular processes such as axonal growth, cell migration and endocytosis. twinfilin (twf) encodes a protein that sequesters actin monomers, but its in vivo functions are unclear. In this study, we characterized twf-null mutants in a metazoan for the first time and found that Drosophila twf negatively regulates F-actin formation in subcellular regions of rapid actin turnover in three different systems, namely postsynaptic neuromuscular junction (NMJ) synapses, migratory border cells and epithelial follicle cells. Loss of twf function results in defects in axonal growth in the brain and border cell migration in the ovary. Additionally, we found that the actin-dependent postsynaptic localization of glutamate receptor GluRIIA, but not GluRIIB, was specifically reduced in twf mutants. More importantly, we showed that twf mutations caused significantly reduced presynaptic endocytosis at NMJ synapses, as detected using the fluorescent dye FM1-43 uptake assay. Furthermore, electrophysiological analysis under high-frequency stimulation showed compromised neurotransmission in twf mutant synapses, confirming an insufficient replenishment of synaptic vesicles. Together, our results reveal that twinfilin promotes actin turnover in multiple cellular processes that are highly dependent on actin dynamics.
Assuntos
Movimento Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Endocitose , Proteínas dos Microfilamentos/metabolismo , Sinapses/metabolismo , Actinas/metabolismo , Animais , Axônios/metabolismo , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/metabolismo , Exocitose , Feminino , Mutação/genética , Neurotransmissores/metabolismo , Especificidade de Órgãos , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo , Profilinas/metabolismo , Receptores de Glutamato/metabolismo , Transmissão Sináptica/fisiologiaRESUMO
OBJECTIVE: To evaluate the efficacy and safety of sustained-release (SR) oxycodone tablets in the treatment of moderate to severe painful diabetic peripheral neuropathy (DPN). Design. This was a multicenter, randomized, open-labeled study. SETTING: This study was completed in 12 hospitals in China. PATIENTS: A total of 80 Chinese patients undergoing moderate to severe painful DPN. INTERVENTIONS: An initial dose of 10mg is recommended to be taken orally every 12 hours. Dose titration was done appropriately according to pain intensity and adverse reactions. OUTCOME MEASURES: Data record included days, dosage, analgesic efficacy, quality of sleep, adverse events, and combination therapy when patients were treated with SR oxycodone tablets. The continuous observation period was 6 weeks. RESULTS: After medication for 1 week, pain was significantly (P<0.01) relieved from 6.8±1.4 to 2.8±1.6. Onset time was within 45 minutes in nearly 60% of the patients, and within 1 hour in nearly 95% of that ones. More than 90% of the patients achieved stable analgesic dose within 3 days. After using SR oxycodone tablets for 1 week, sleep quality was significantly (P<0.01) improved. In week 1, the average dose of SR oxycodone tablets was 16.63±7.79mg. The average daily dose of most patients was about 20mg after 2 weeks. In all the enrolled patients, 38 (47.5%) had adverse reactions. No serious adverse reactions took place. CONCLUSION: The results of this clinical observation further elaborated the efficacy and safety of SR oxycodone tablets in the treatment of moderate to severe painful diabetic peripheral neuropathy in China.
Assuntos
Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/fisiopatologia , Oxicodona/administração & dosagem , Manejo da Dor/métodos , Vigilância de Produtos Comercializados/métodos , Idoso , China , Preparações de Ação Retardada/administração & dosagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , ComprimidosRESUMO
BACKGROUND: Pudendal neuralgia (PN) is one of the most common forms of genital pain. About 4% or higher of patients suffering from chronic pain. OBJECTIVES: The aim of this study was to evaluate the risk factors for prediction of refractory PN (RPN). STUDY DESIGN: A retrospective multivariate analysis study. SETTING: This retrospective analysis included 112 patients with PN who received the pudendal nerve block treatment at the Pain Department of General Hospital of People's Liberation Army. METHODS: Univariate and multivariable logistic regression analyses were used for covariates selection. A nomogram was developed to estimate nonresponse to the pudendal nerve block. RESULTS: The median age of patients and duration of patients were 48.0 and 1.25 years, respectively. Among 112 patients, there were 64 good responders to the pudendal nerve block for neuropathic pain and 48 nonresponders. Multivariate analysis of 112 patients with PN demonstrated high self-rating depression scale scores (> 32) (odds ratio [OR], 95% confidence interval [CI]: 0.11, 0.01-0.77), damage to more than 2 terminal branches (OR, 95% CI: 0.22, 0.07-0.71), sensory deficit at S2-S4 on the dermatome map (OR, 95% CI: 0.22, 0.05-0.90), and duration of pain (> 4 years) (OR, 95% CI: 0.10, 0.03-0.42) were significant prognostic factors for nonresponse to the pudendal nerve block. LIMITATIONS: There are information biases for retrospective analysis, thus making it more difficult to come up with definitive conclusions. Large-scale randomized clinical trials are warranted to evaluate the risk factors for prediction of RPN. CONCLUSIONS: A longer duration of pain was correlated with a worse prognosis of the neurological disease. Patients with depression were prone to nonresponse to the pudendal nerve block treatment. Pain involved in more than 2 terminal branches and small fibers, affected at S2-S4 dermatome map, were considered to poor prognosis.