RESUMEN
The elasticities of double-stranded (ds) DNA and RNA, which are critical to their biological functions and applications in materials science, can be significantly modulated by solution conditions such as ions and temperature. However, there is still a lack of a comprehensive understanding of the role of solvents in the elasticities of dsRNA and dsDNA in a comparative way. In this work, we explored the effect of ethanol solvent on the elasticities of dsRNA and dsDNA by magnetic tweezers and all-atom molecular dynamics simulations. We found that the bending persistence lengths and contour lengths of dsRNA and dsDNA decrease monotonically with the increase in ethanol concentration. Furthermore, the addition of ethanol weakens the positive twist-stretch coupling of dsRNA, while promotes the negative twist-stretch coupling of dsDNA. Counter-intuitively, the lower dielectric environment of ethanol causes a significant re-distribution of counterions and enhanced ion neutralization, which overwhelms the enhanced repulsion along dsRNA/dsDNA, ultimately leading to the softening in bending for dsRNA and dsDNA. Moreover, for dsRNA, ethanol causes slight ion-clamping across the major groove, which weakens the major groove-mediated twist-stretch coupling, while for dsDNA, ethanol promotes the stretch-radius correlation due to enhanced ion binding and consequently enhances the helical radius-mediated twist-stretch coupling.
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ADN , Etanol , Simulación de Dinámica Molecular , ARN Bicatenario , Etanol/química , ADN/química , ARN Bicatenario/química , Elasticidad , Conformación de Ácido NucleicoRESUMEN
The subtle differences in the chemical structures of double-stranded (ds) RNA and DNA lead to significant variations in their biological roles and medical implications, largely due to their distinct biophysical properties, such as bending stiffness. Although it is well known that A-form dsRNA is stiffer than B-form dsDNA under physiological salt conditions, the underlying cause of this difference remains unclear. In this study, we employ high-precision magnetic-tweezer experiments along with molecular dynamics simulations and reveal that the relative bending stiffness between dsRNA and dsDNA is primarily determined by the structure- and salt-concentration-dependent ion distribution around their helical structures. At near-physiological salt conditions, dsRNA shows a sparser ion distribution surrounding its phosphate groups compared to dsDNA, causing its greater stiffness. However, at very high monovalent salt concentrations, phosphate groups in both dsRNA and dsDNA become fully neutralized by excess ions, resulting in a similar intrinsic bending persistence length of approximately 39 nm. This similarity in intrinsic bending stiffness of dsRNA and dsDNA is coupled to the analogous fluctuations in their total groove widths and further coupled to the similar fluctuation of base-pair inclination, despite their distinct A-form and B-form helical structures.
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ADN , ARN Bicatenario , Emparejamiento Base , ADN/química , Conformación de Ácido Nucleico , Fosfatos , ARN Bicatenario/química , Biología Molecular/métodos , Simulación de Dinámica MolecularRESUMEN
Chronic pain often develops severe mood changes such as depression. However, how chronic pain leads to depression remains elusive and the mechanisms determining individuals' responses to depression are largely unexplored. Here we found that depression-like behaviors could only be observed in 67.9% of mice with chronic neuropathic pain, leaving 32.1% of mice with depression resilience. We determined that the spike discharges of the ventral tegmental area (VTA)-projecting lateral habenula (LHb) glutamatergic (Glu) neurons were sequentially increased in sham, resilient and susceptible mice, which consequently inhibited VTA dopaminergic (DA) neurons through a LHbGlu-VTAGABA-VTADA circuit. Furthermore, the LHbGlu-VTADA excitatory inputs were dampened via GABAB receptors in a pre-synaptic manner. Regulation of LHb-VTA pathway largely affected the development of depressive symptoms caused by chronic pain. Our study thus identifies a pivotal role of the LHb-VTA pathway in coupling chronic pain with depression and highlights the activity-dependent contribution of LHbGlu-to-VTADA inhibition in depressive behavioral regulation.
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Dolor Crónico , Habénula , Ratones , Animales , Área Tegmental Ventral/metabolismo , Habénula/metabolismo , Depresión , Ácido gamma-Aminobutírico/metabolismoRESUMEN
Nucleic acid deformations play important roles in many biological processes. The physical understanding of nucleic acid deformation by environmental stimuli is limited due to the challenge in the precise measurement of RNA and DNA deformations and the complexity of interactions in RNA and DNA. Magnetic tweezers experiments provide an excellent opportunity to precisely measure DNA and RNA twist changes induced by environmental stimuli. In this work, we applied magnetic tweezers to measure double-stranded RNA twist changes induced by salt and temperature changes. We observed RNA unwinds when lowering salt concentration, or increasing temperature. Our molecular dynamics simulations revealed the mechanism: lowering salt concentration or increasing temperature enlarges RNA major groove width, which causes twist decrease through twist-groove coupling. Combining these results with previous results, we found some universality in RNA and DNA deformations induced by three different stimuli: salt change, temperature, and stretching force. For RNA, these stimuli first modify the major groove width, which is transduced into twist change through twist-groove coupling. For DNA, these stimuli first modify diameter, which is transduced into twist change through twist-diameter coupling. Twist-groove coupling and twist-diameter coupling appear to be utilized by protein binding to reduce DNA and RNA deformation energy cost upon protein binding.
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ADN , ARN Bicatenario , Conformación de Ácido Nucleico , Unión Proteica , Temperatura , ADN/química , Cloruro de Sodio , Cloruro de Sodio DietéticoRESUMEN
5-Methyl-cytosine (5mC) is one of the most important DNA modifications and plays versatile biological roles. It is well known that 5mC stabilizes DNA duplexes. However, it remains unclear how 5mC affects the kinetics of DNA melting and hybridization. Here, we studied the kinetics of unzipping and rezipping using a 502-bp DNA hairpin by single-molecule magnetic tweezers. Under constant loading rates, 5mC increases the unzipping force but counterintuitively decreases the rezipping force at various salt and temperature conditions. Under constant forces, the non-methylated DNA hops between metastable states during unzipping and rezipping, which implies low energy barriers. Surprisingly, the 5mC DNA can't rezip after fully unzipping unless much lower forces are applied, where it rezips stochastically in a one-step manner, which implies 5mC kinetically hinders DNA hybridization and high energy barriers in DNA hybridization. All-atom molecular dynamics simulations reveal that the 5mC kinetically hinders DNA hybridization due to steric effects rather than electrostatic effects caused by the additional methyl groups of cytosines. Considering the possible high speed of DNA unzipping and zipping during replication and transcription, our findings provide new insights into the biological roles of 5mC.
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5-Metilcitosina , ADN , Citosina , ADN/química , Fenómenos Magnéticos , Conformación de Ácido Nucleico , Hibridación de Ácido NucleicoRESUMEN
When stretched, both DNA and RNA duplexes change their twist angles through twist-stretch coupling. The coupling is negative for DNA but positive for RNA, which is not yet completely understood. Here, our magnetic tweezers experiments show that the coupling of RNA reverses from positive to negative by multivalent cations. Combining with the previously reported tension-induced negative-to-positive coupling reversal of DNA, we propose a unified mechanism of the couplings of both RNA and DNA based on molecular dynamics simulations. Two deformation pathways are competing when stretched: shrinking the radius causes positive couplings but widening the major groove causes negative couplings. For RNA whose major groove is clamped by multivalent cations and canonical DNA, their radii shrink when stretched, thus exhibiting positive couplings. For elongated DNA whose radius already shrinks to the minimum and canonical RNA, their major grooves are widened when stretched, thus exhibiting negative couplings.
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ADN , ARN , Cationes , ADN/metabolismo , Simulación de Dinámica Molecular , Conformación de Ácido NucleicoRESUMEN
Ion-mediated effective interactions are important for the structure and stability of charged particles such as colloids and nucleic acids. It has been known that the intrinsic electrostatic repulsion between like-charged particles can be modulated into effective attraction by multivalent ions. In this work, we examined the dependence of multivalent ion-mediated attraction between like-charged colloidal particles on the particle charge in a wide range by extensive Monte Carlo simulations. Our calculations show that for both divalent and trivalent salts, the effective attraction between like-charged colloidal particles becomes stronger with the increase of the particle charge, whereas it gradually becomes weakened when the particle charge exceeds a "critical" value. Correspondingly, as the particle charge is increased, the driving force for such effective attraction transits from an attractive electrostatic force to an attractive depletion force, and the attraction weakening by high particle charges is attributed to the transition of electrostatic force from attraction to repulsion. Our analyses suggest that the attractive depletion force and the repulsive electrostatic force at high particle charges result from the Coulomb depletion which suppresses the counterion condensation in the limited region between two like-charged colloidal particles. Moreover, our extensive calculations indicate that the "critical" particle charge decreases apparently for larger ions and smaller colloidal particles due to stronger Coulomb depletion and decreases slightly at higher salt concentrations due to the slightly enhanced Coulomb depletion in the intervening space between colloidal particles. Encouragingly, we derived an analytical formula for the "critical" particle charge based on the Lindemann melting law.
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BACKGROUND: Norepinephrine infusion decreases hypotension after spinal anesthesia during cesarean section. This study aimed to compare the efficacy of norepinephrine infusion and ephedrine bolus against post-spinal hypotension in parturients. METHODS: In this double-blinded, randomized controlled clinical trial, parturients scheduled for elective cesarean section were randomly allocated to receive norepinephrine infusion (0.05 µg·kg-1·min-1) just before spinal anesthesia continuing for 30 min or ephedrine bolus (0.15âmg/kg) just before spinal anesthesia. A rescue bolus (5 µg norepinephrine for the norepinephrine group, and 5 mg ephedrine for the ephedrine group) was administered whenever hypotension occurred. Our primary outcome was the incidence of hypotension within 30 min of spinal anesthesia administration. Secondary outcomes included maternal and neonatal outcomes 30 min after spinal block, and neonatal cerebral oxygenation 10 min after birth. RESULTS: In total, 190 patients were enrolled; of these patients, 177 were included in the final analysis. Fewer patients suffered hypotension in the norepinephrine group than in the ephedrine group (29.5% vs. 44.9%, odds ratio [OR]: 0.51, 95% confidence interval [CI]: 0.28-0.95, Pâ=â0.034). Moreover, the tachycardia frequency was lower in the norepinephrine group than in the ephedrine group (OR: 0.22, 95% CI: 0.11-0.44, Pâ<â0.001), and patients suffered less nausea and vomiting (OR: 0.28, 95% CI: 0.11-0.70, Pâ=â0.004). There was no difference in Apgar scores and umbilical arterial blood gas analysis between the two groups. However, neonatal cerebral regional saturations were significantly higher after birth in the norepinephrine group than in the ephedrine group (mean difference: 2.0%, 95% CI: 0.55%-3.45%, Pâ=â0.008). CONCLUSION: In patients undergoing elective cesarean section with spinal anesthesia, norepinephrine infusion compared to ephedrine bolus resulted in less hypotension and tachycardia, and exhibited potential neonatal benefits. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02542748; https://clinicaltrials.gov/ct2/show/record/NCT02542748.
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Anestesia Raquidea , Hipotensión , Anestesia Raquidea/efectos adversos , Cesárea/efectos adversos , Método Doble Ciego , Femenino , Humanos , Hipotensión/tratamiento farmacológico , Hipotensión/prevención & control , Recién Nacido , Fenilefrina , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Vasoconstrictores/uso terapéuticoRESUMEN
CpG methylation of DNA is common in mammalian cells. In sperm, the DNA has the highest level of CpG methylation and is condensed into toroidal structures. How CpG methylation affects DNA structures and interactions is important to understand its biological roles but is largely unknown. Using an RNA-DNA-RNA structure, we observed the equilibrium hopping dynamics between the condensed and extended states of DNA in the presence of polyamines or polylysine peptide as a reduced model of histone tails. Combing with the measured DNA elasticities, we report that CpG methylation of each cytosine nucleotide substantially increases DNA-DNA attraction by up to 0.2 kBT. For the DNA with 57% GC content, the relative increase caused by CpG methylation is up to 32% for the spermine-induced DNA-DNA attraction and up to 9% for the polylysine-induced DNA-DNA attraction. These findings help us to evaluate the energetic contributions of CpG methylation in sperm development and chromatin regulation.
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Cromatina/química , Citosina/química , Metilación de ADN , ADN/análisis , ADN/química , Fenómenos Magnéticos , Conformación de Ácido Nucleico , Islas de CpGRESUMEN
BACKGROUND: Transcutaneous electric acupoint stimulation (TEAS) has shown benefits when used peri-operatively. However, the role of numbers of areas with acupoint stimulation is still unclear. Therefore, we report the protocol of a randomized controlled trial of using TEAS in elderly patients subjected to gastrointestinal surgery, and comparing dual-acupoint and single-acupoint stimulation. METHODS/DESIGN: A multicenter, randomized, controlled, three-arm design, large-scale trial is currently undergoing in four hospitals in China. Three hundred and forty-five participants are randomly assigned to three groups in a 1:1:1 ratio, receiving dual-acupoint TEAS, single-acupoint TEAS, and no stimulation, respectively. The primary outcome is incidence of pulmonary complications at 30 days after surgery. The secondary outcomes include the incidence of pulmonary complications at 3 days after surgery; the all-cause mortality within 30 days and 1 year after surgery; admission to the intensive care unit (ICU) and length of ICU stay within 30 days after surgery; the length of postoperative hospital stay; and medical costs during hospitalization after surgery. DISCUSSION: The result of this trial (which will be available in September 2019) will confirm whether TEAS before and during anesthesia could alleviate the postoperative pulmonary complications after gastrointestinal surgery in elderly patients, and whether dual-acupoint stimulation is more effective than single-acupoint stimulation. TRIALS REGISTRATIONS: ClinicalTrials.gov, ID: NCT03230045 . Registered on 10 July 2017.
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Puntos de Acupuntura , Procedimientos Quirúrgicos del Sistema Digestivo , Electroacupuntura/métodos , Tracto Gastrointestinal/cirugía , Enfermedades Respiratorias/prevención & control , Factores de Edad , Anciano , China , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Procedimientos Quirúrgicos del Sistema Digestivo/economía , Procedimientos Quirúrgicos del Sistema Digestivo/mortalidad , Electroacupuntura/efectos adversos , Electroacupuntura/economía , Electroacupuntura/mortalidad , Femenino , Costos de la Atención en Salud , Humanos , Unidades de Cuidados Intensivos , Tiempo de Internación , Masculino , Estudios Multicéntricos como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Enfermedades Respiratorias/economía , Enfermedades Respiratorias/etiología , Enfermedades Respiratorias/mortalidad , Factores de Riesgo , Factores de Tiempo , Resultado del TratamientoRESUMEN
OBJECTIVE: To report the 12-month results of the first human uterus transplantation case using robot-assisted uterine retrieval. This type of transplantation may become a treatment for permanent uterine factor infertility. DESIGN: Case study. SETTING: University hospital. PATIENT(S): A 22-year-old woman with complete müllerian agenesis who underwent a previous surgery for vaginal reconstruction. The live uterine donor was her mother. INTERVENTION(S): The uterus transplantation procedure consisted of robot-assisted uterine procurement, orthotopic replacement and fixation of the retrieved uterus, revascularization, and end-to-side anastomoses of bilateral hypogastric arteries and ovarian-uterine vein to the bilateral external iliac arteries and veins. MAIN OUTCOME MEASURE(S): Data from preoperative investigations, surgery, and follow-up (12 months). RESULT(S): The duration of the donor and recipient surgeries were 6 and 8 hours, 50 minutes, respectively. No immediate perioperative complications occurred in the recipient or donor. The recipient experienced menarche 40 days after transplant surgery, and she has had 12 menstrual cycles since the surgery. No rejection episodes occurred in the recipient. CONCLUSION(S): These results demonstrate the feasibility of live-donor uterine transplantation with a low-dose immunosuppressive protocol and the role of DaVinci robotic assistance during human uterine procurement. CLINICAL TRIAL REGISTRATION NUMBER: XJZT12Z06.
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Trastornos del Desarrollo Sexual 46, XX/cirugía , Anomalías Congénitas/cirugía , Histerectomía/métodos , Conductos Paramesonéfricos/anomalías , Ovario/irrigación sanguínea , Procedimientos Quirúrgicos Robotizados/métodos , Útero/trasplante , Venas/trasplante , Femenino , Humanos , Conductos Paramesonéfricos/cirugía , Ovario/trasplante , Procedimientos de Cirugía Plástica/métodos , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Sepsis is a major cause of mortality in Intensive Care Units. Anesthetic dose isoflurane and 100% oxygen were proved to be beneficial in sepsis; however, their application in septic patients is limited because long-term hyperoxia may induce oxygen toxicity and anesthetic dose isoflurane has potential adverse consequences. This study was scheduled to find the optimal combination of isoflurane and oxygen in protecting experimental sepsis and its mechanisms. METHODS: The effects of combined therapy with isoflurane and oxygen on lung injury and sepsis were determined in animal models of sepsis induced by cecal ligation and puncture (CLP) or intraperitoneal injection of lipopolysaccharide (LPS) or zymosan. Mouse RAW264.7 cells or human peripheral blood mononuclear cells (PBMCs) were treated by LPS to probe mechanisms. The nuclear factor kappa B (NF-κB) signaling molecules were examined by Western blot and cellular immunohistochemistry. RESULTS: The 0.5 minimum alveolar concentration (MAC) isoflurane in 60% oxygen was the best combination of oxygen and isoflurane for reducing mortality in experimental sepsis induced by CLP, intraperitoneal injection of LPS, or zymosan. The 0.5 MAC isoflurane in 60% oxygen inhibited proinflammatory cytokines in peritoneal lavage fluids (tumor necrosis factor-alpha [TNF-ß]: 149.3 vs. 229.7 pg/ml, interleukin [IL]-1ß: 12.5 vs. 20.6 pg/ml, IL-6: 86.1 vs. 116.1 pg/ml, and high-mobility group protein 1 [HMGB1]: 323.7 vs. 449.3 ng/ml; all P< 0.05) and serum (TNF-ß: 302.7 vs. 450.7 pg/ml, IL-1ß: 51.7 vs. 96.7 pg/ml, IL-6: 390.4 vs. 722.5 pg/ml, and HMGB1: 592.2 vs. 985.4 ng/ml; all P< 0.05) in septic animals. In vitro experiments showed that the 0.5 MAC isoflurane in 60% oxygen reduced inflammatory responses in mouse RAW264.7 cells, after LPS stimulation (all P< 0.05). Suppressed activation of NF-κB pathway was also observed in mouse RAW264.7 macrophages and human PBMCs after LPS stimulation or plasma from septic patients. The 0.5 MAC isoflurane in 60% oxygen also prevented the increases of phospho-IKKß/ß, phospho-IκBß, and phospho-p65 expressions in RAW264.7 macrophages after LPS stimulation (all P< 0.05). CONCLUSION: Combined administration of a sedative dose of isoflurane with 60% oxygen improves survival of septic animals through reducing inflammatory responses.
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Anestesia/métodos , Inflamación/tratamiento farmacológico , Isoflurano/uso terapéutico , Lesión Pulmonar/tratamiento farmacológico , Oxígeno/uso terapéutico , Sepsis/tratamiento farmacológico , Sepsis/inmunología , Adulto , Animales , Western Blotting , Líquido del Lavado Bronquioalveolar , Modelos Animales de Enfermedad , Femenino , Humanos , Leucocitos Mononucleares/metabolismo , Receptores de Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Lesión Pulmonar/inmunología , Lesión Pulmonar/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Peroxidasa/metabolismo , Células RAW 264.7 , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The glyceraldehyde-3-phosphate dehydrogenase (GAPDH)/Siah1 signaling pathway has been recognized as a sensor of nitric oxide (NO). It is associated with a variety of injurious conditions, suggesting its therapeutic potential for spinal cord injury (SCI). Sivelestat sodium (SIV), a neutrophil elastase (NE) inhibitor initially used to treat acute lung injury, has been known to protect against compression-induced and ischemic SCI. However, little is known about the relationship between the GAPDH/Siah1 cascade and SIV. Thus, we aimed to assess the role of GAPDH/Siah1 cascade in traumatic SCI and its possible link with SIV. Rats were assigned to four groups: sham group, SCI group, 5-mg/kg SIV group, and 10-mg/kg SIV. The traumatic SCI was induced by dropping a 10-g impactor from a height of 25mm on the dorsal surface of T9 and T10. SIV was injected intraperitoneally immediately after surgery. Our results showed that the nuclear translocation of GAPDH was induced together with the nuclear translocation of Siah1 and the formation of the GAPDH/Siah1 complex in the spinal cord after traumatic SCI. However, the activation of the GAPDH/Siah1 cascade was attenuated by treatment with SIV. We also found that SIV suppressed apoptosis, NE and inducible nitric oxide synthase (iNOS) protein expressions, the number of NE and iNOS immunostained cells, the production of interleukin (IL)-1ß and tumor necrosis factor-alpha (TNF-α), and the activation of nuclear factor kappa light-chain enhancer of activated B cells (NF-κB) signaling in the spinal cord. The behavioral tests showed that SIV promoted functional recovery after traumatic SCI as reflected in the sustained increase in the Basso-Beattie-Bresnahan (BBB) scores throughout the observation period. In conclusion, our results reveal GAPDH/Siah1 as a novel signaling pathway during the progression of SCI, which can be blocked by SIV.
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Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Glicina/análogos & derivados , Fármacos Neuroprotectores/farmacología , Proteínas Nucleares/metabolismo , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/metabolismo , Sulfonamidas/farmacología , Ubiquitina-Proteína Ligasas/metabolismo , Transporte Activo de Núcleo Celular/efectos de los fármacos , Transporte Activo de Núcleo Celular/fisiología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Glicina/farmacología , Interleucina-1beta/metabolismo , Masculino , FN-kappa B/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Distribución Aleatoria , Ratas Sprague-Dawley , Recuperación de la Función/efectos de los fármacos , Recuperación de la Función/fisiología , Transducción de Señal/efectos de los fármacos , Médula Espinal/efectos de los fármacos , Médula Espinal/metabolismo , Médula Espinal/patología , Traumatismos de la Médula Espinal/patología , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Previous studies have demonstrated that orexinergic neurons involve in promoting emergence from anesthesia of propofol, an intravenous anesthetics, while whether both of orexin-A and orexin-B have promotive action on emergence via mediation of basal forebrain (BF) in isoflurane anesthesia has not been elucidated. In this study, we observed c-Fos expressions in orexinergic neurons following isoflurane inhalation (for 0, 30, 60, and 120min) and at the time when the righting reflex returned after the cessation of anesthesia. The plasma concentrations of orexin-A and -B in anesthesia-arousal process were measured by radioimmunoassay. Orexin-A and -B (30 or 100pmol) or the orexin receptor-1 and -2 antagonist SB-334867A and TCS-OX2-29 (5 or 20µg) were microinjected into the basal forebrain respectively. The effects of them on the induction (loss of the righting reflex) and the emergence time (return of the righting reflex) under isoflurane anesthesia were observed. The results showed that the numbers of c-Fos-immunoreactive orexinergic neurons in the hypothalamus decreased over time with continued isoflurane inhalation, but restored at emergence. Similar alterations were observed in changes of plasma orexin-A concentrations but not in orexin-B during emergence. Administration of orexins had no effect on the induction time, but orexin-A facilitated the emergence of rats from isoflurane anesthesia while orexin-B didn't. Conversely, microinjection of the orexin receptor-1 antagonist SB-334867A delayed emergence from isoflurane anesthesia. The results indicate that orexin-A plays a promotive role in the emergence of isoflurane anesthesia and this effect is mediated by the basal forebrain.
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Anestésicos por Inhalación/administración & dosificación , Prosencéfalo Basal/efectos de los fármacos , Prosencéfalo Basal/metabolismo , Isoflurano/administración & dosificación , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Orexinas/fisiología , Animales , Benzoxazoles/administración & dosificación , Masculino , Naftiridinas , Antagonistas de los Receptores de Orexina/administración & dosificación , Orexinas/administración & dosificación , Orexinas/sangre , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Ratas Sprague-Dawley , Urea/administración & dosificación , Urea/análogos & derivadosRESUMEN
BACKGROUND: Chronic low back pain affects daily activities at home and workplaces and causes a huge economic burden. Current therapeutic options are very limited and the effects of available pharmacological agents are less than satisfactory. While NSAIDs might be effective for the short term and opioids might help with urgent pain relief and improving the life quality, their long-term use is associated with significant side effects and drug misuse or abuse. To seek alternative pharmacological agents for effective treatment, we examined the therapeutic potential of the extracts of Vaccinia variola-inoculated rabbit skin (Analgecine, abbreviated as AGC) in patients with chronic low back pain due to degenerative vertebral disorders. METHODS: In this randomized multi-center double-blind placebo-controlled phase 3 clinical trial (Chinese Clinical Trial Registry number 2009L01498), we enrolled patients (aged 26-70 years) with chronic low back pain for at least 3 months due to degenerative spinal (vertebral) disorders from 7 medical centers in China, and randomly allocated 459 participants to receive oral AGC or placebo for 28 days to study the efficacy and safety of AGC. Randomization was performed according to a centralized randomization schedule, which was blocked by study sites and generated by an unmasked statistician independent of study conduct and data analysis. Both participants and staff at each study site were masked to treatment assignment. The primary efficacy endpoint was the change of the mean pain intensity, based on an 11-point numerical rating scale, between the baseline and the last week of treatment, with the primary efficacy analysis of intention to treat. The ratio between exposed and unexposed groups was designed to be 3:1 in order to increase the likelihood of demonstrating the AGC effect upon repeated measures. RESULTS: 347 patients were assigned to receive AGC (4 units/tablet; 2 tablets twice a day) and 112 patients were to take placebo. Among them, 324 patients taking AGC and 112 receiving placebo completed the assessment. Patients receiving AGC reported significant pain relief at the end of week 2 and 3 compared to those taking placebo, with mean reduction of the pain scores as 1.7 vs. 0.9 at week 2 (p < 0.0001) and 2.8 vs. 1.2 at week 3 (p < 0.0001). A total of 47 AGC-treated patients reported 85 treatment emergent adverse events while 16 patients taking placebo reported 26 events, but no serious side effects were found to be related to AGC treatment. CONCLUSION: Analgecine (AGC, 8 units twice daily) effectively alleviates chronic low back pain due to degenerative vertebral disorders when compared to placebo and is well tolerated by tested individuals, and can be considered as a first-line treatment for chronic low pain due to degenerative vertebral diseases.
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Anestésicos por Inhalación/toxicidad , Isoflurano/toxicidad , Orexinas/deficiencia , Privación de Sueño/inducido químicamente , Privación de Sueño/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Técnica del Anticuerpo Fluorescente , Hipnóticos y Sedantes/administración & dosificación , Hipotálamo/efectos de los fármacos , Hipotálamo/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Orexinas/administración & dosificación , Orexinas/sangre , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Privación de Sueño/tratamiento farmacológico , Sueño REM/efectos de los fármacos , Sueño REM/fisiologíaRESUMEN
BACKGROUND: Sudden cardiac arrest is a leading cause of death worldwide. Three-fourths of cardiac arrest patients die before hospital discharge or experience significant neurological damage. Hydrogen-rich saline, a portable, easily administered, and safe means of delivering hydrogen gas, can exert organ-protective effects through regulating oxidative stress, inflammation, and apoptosis. We designed this study to investigate whether hydrogen-rich saline treatment could improve survival and neurological outcome after cardiac arrest and cardiopulmonary resuscitation, and the mechanism responsible for this effect. METHODS: Sprague-Dawley rats were subjected to 8 minutes of cardiac arrest by asphyxia. Different doses of hydrogen-rich saline or normal saline were administered IV at 1 minute before cardiopulmonary resuscitation, followed by injections at 6 and 12 hours after restoration of spontaneous circulation, respectively. We assessed survival, neurological outcome, oxidative stress, inflammation biomarkers, and apoptosis. RESULTS: Hydrogen-rich saline treatment dose dependently improved survival and neurological function after cardiac arrest/resuscitation. Moreover, hydrogen-rich saline treatment dose dependently ameliorated brain injury after cardiac arrest/resuscitation, which was characterized by the increase of survival neurons in hippocampus CA1, reduction of brain edema in cortex and hippocampus, preservation of blood-brain barrier integrity, as well as the decrease of serum S100ß and neuron-specific enolase. Furthermore, we found that the beneficial effects of hydrogen-rich saline treatment were associated with decreased levels of oxidative products (8-iso-prostaglandin F2α and malondialdehyde) and inflammatory cytokines (tumor necrosis factor-α, interleukin-1ß, and high-mobility group box protein 1), as well as the increased activity of antioxidant enzymes (superoxide dismutase and catalase) in serum and brain tissues. In addition, hydrogen-rich saline treatment reduced caspase-3 activity in cortex and hippocampus after cardiac arrest/resuscitation. CONCLUSIONS: Hydrogen-rich saline treatment improved survival and neurological outcome after cardiac arrest/resuscitation in rats, which was partially mediated by reducing oxidative stress, inflammation, and apoptosis.
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Lesiones Encefálicas/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Reanimación Cardiopulmonar , Fluidoterapia/métodos , Paro Cardíaco/terapia , Hidrógeno/administración & dosificación , Fármacos Neuroprotectores/administración & dosificación , Cloruro de Sodio/administración & dosificación , Administración Intravenosa , Animales , Antioxidantes/metabolismo , Apoptosis/efectos de los fármacos , Biomarcadores/sangre , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Encéfalo/metabolismo , Encéfalo/patología , Lesiones Encefálicas/sangre , Lesiones Encefálicas/patología , Caspasa 3/metabolismo , Citocinas/sangre , Dinoprost/análogos & derivados , Dinoprost/sangre , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Paro Cardíaco/diagnóstico , Mediadores de Inflamación/sangre , Masculino , Malondialdehído/sangre , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Estrés Oxidativo/efectos de los fármacos , Fosfopiruvato Hidratasa/metabolismo , Ratas , Ratas Sprague-Dawley , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Factores de TiempoRESUMEN
N-myc downstream-regulated gene 2 (Ndrg2) is a newly identified molecule that is mainly expressed in astrocytes within the central nervous system (CNS) and is involved in the proliferation and activation of astrocytes. 17ß-estradiol (E2) is one of the most important circulating hormones, and in the CNS, astrocytes are a target and potential mediator of the action of E2. Our most recent study found that DPN, an estrogen receptor (ER) ß-specific agonist, activated the Ndrg2 promoter and elevated endogenous NDRG2 protein expression in MCF7, HSG and T-47D cells. However, whether E2 regulates Ndrg2 expression in astrocytes remains unknown. Here, we conducted both in vivo and in vitro experiments and found that ERß co-localized with NDRG2 in astrocytes. Furthermore, in primary cultured astrocytes, we demonstrated that E2 up-regulated Ndrg2 mRNA and protein expression in a dose- and time-dependent manner and that the ERß agonist DPN but not the ERα agonist PPT up-regulated Ndrg2 expression. In vivo, we found that in the hippocampus of adult ovariectomized (OVX) female mice, Ndrg2 mRNA and protein expression were significantly decreased compared with those in normal adult female mice. After the OVX mice received continuous subcutaneous injections of 50µg/kg E2, 100µg/kg E2 or the ERß agonist DPN for 10 days, the Ndrg2 expression significantly increased compared with that of the OVX mice. Our results indicate that E2 may affect astrocytes by regulating Ndrg2 expression.
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Astrocitos/metabolismo , Estradiol/farmacología , Estrógenos/farmacología , Proteínas/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Animales , Astrocitos/efectos de los fármacos , Células Cultivadas , Receptor beta de Estrógeno/agonistas , Receptor beta de Estrógeno/metabolismo , Femenino , Hipocampo/metabolismo , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/metabolismo , Regulación hacia ArribaRESUMEN
BACKGROUND: Delayed emergence from general anesthesia frequently occurs in elderly patients, but the reason is not clear. Orexin has been shown to be involved in arousal from general anesthesia. In this study, we examined plasma orexin-A levels in both elderly and young patients during the anesthesia arousal cycle. METHODS: We recruited 41 patients scheduled for elective lumbar surgery and eventually evaluated 34 patients. Patients were divided into a young group (age 30-55, N = 16) and an elderly group (age 65-77, N = 18). Anesthesia with sevoflurane-remifentanil was titrated to maintain the Bispectral Index between 45 and 65. The times from stopping anesthesia to eyes opening and extubation were recorded. Arterial blood was collected, and plasma orexin-A was determined by radioimmunoassay at the following 4 time points: preanesthesia (T0), 1 hour after anesthesia induction (T1), emergence (5 minutes after tracheal extubation) (T2), and 30 minutes after tracheal extubation (T3). RESULTS: The times from stopping anesthesia to eyes opening and tracheal extubation were both significantly longer in the elderly group than in the young group (P = 0.004, P = 0.01, respectively). Basal (T0) orexin-A levels were higher in the elderly group than in the young group (T0, 26.13 ± 1.25 vs 17.9 ± 1.30 pg/mL, P < 0.0001). Plasma orexin-A levels did not change during induction of anesthesia in either group but significantly increased at T2 (vs T0, P <0.0001) in both elderly (35.0 ± 1.7 pg/mL) and young (29.2 ± 1.9 pg/mL) groups. Orexin-A levels were significantly higher in the elderly than in the young group at T1, T2, and T3. CONCLUSION: Plasma orexin-A levels are not responsible for the delayed emergence from general anesthesia in elderly patients.
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Envejecimiento/metabolismo , Anestesia General , Anestésicos por Inhalación , Anestésicos Intravenosos , Péptidos y Proteínas de Señalización Intracelular/sangre , Región Lumbosacra/cirugía , Éteres Metílicos , Neuropéptidos/sangre , Piperidinas , Adulto , Anciano , Periodo de Recuperación de la Anestesia , Anestésicos por Inhalación/farmacocinética , Glucemia/metabolismo , Monitores de Conciencia , Femenino , Humanos , Masculino , Éteres Metílicos/farmacocinética , Persona de Mediana Edad , Orexinas , Radioinmunoensayo , Remifentanilo , Tamaño de la Muestra , SevofluranoRESUMEN
Estrogen has been shown to have neuroprotective effects in numerous experimental studies involving young and adult animals. However, several clinical trials have found that in aged postmenopausal women who received estrogen replacement therapy, there did not appear to be a reduction in the incidence of stroke. The aim of this study was to investigate the effects of physiological dosages of estrogen on aged female mice subjected to ischemia-reperfusion injury. Adult ovariectomized (OVX) female mice and 22-month-old female mice received daily subcutaneous injections of 100 µg/kg or 300 µg/kg 17ß-estradiol (E2) at the back of the neck for four weeks, and the expression levels of estrogen receptor (ER) α and ß in the cerebral cortex were determined using real-time PCR and Western blotting analyses. To mimic ischemic stroke, the mice received middle cerebral artery occlusion (MCAO) treatment for 1h followed by a 24-h reperfusion period. The mice were then subjected to neurological deficit testing and infarct volume evaluation. The aged mice showed higher neurological deficit scores and larger infarct volumes compared with the adult mice. Both the lower and higher physiological dosages of E2 significantly improved the neurological test scores and decreased the infarct volume in the adult mice; however, E2 showed no neuroprotective effects in the aged mice. Furthermore, the protein expression of ERα and ERß in the cerebral cortex was significantly decreased in the aged mice compared with the adult mice, and this decrease was not rescued by E2 treatment. These results indicate that the down-regulation of ERα and ERß in the cerebral cortex may contribute to the loss of estrogen efficacy against ischemic injury in aged females and may point to new therapies for ischemic stroke in aged postmenopausal women.