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Electrochemical carbon-capture technologies, with renewable electricity as the energy input, are promising for carbon management but still suffer from low capture rates, oxygen sensitivity or system complexity1-6. Here we demonstrate a continuous electrochemical carbon-capture design by coupling oxygen/water (O2/H2O) redox couple with a modular solid-electrolyte reactor7. By performing oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) redox electrolysis, our device can efficiently absorb dilute carbon dioxide (CO2) molecules at the high-alkaline cathode-membrane interface to form carbonate ions, followed by a neutralization process through the proton flux from the anode to continuously output a high-purity (>99%) CO2 stream from the middle solid-electrolyte layer. No chemical inputs were needed nor side products generated during the whole carbon absorption/release process. High carbon-capture rates (440 mA cm-2, 0.137 mmolCO2 min-1 cm-2 or 86.7 kgCO2 day-1 m-2), high Faradaic efficiencies (>90% based on carbonate), high carbon-removal efficiency (>98%) in simulated flue gas and low energy consumption (starting from about 150 kJ per molCO2) were demonstrated in our carbon-capture solid-electrolyte reactor, suggesting promising practical applications.
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BACKGROUND: Pegylated liposomal doxorubicin (PLD) is a liposome-encapsulated form of doxorubicin with equivalent efficacy and less cardiotoxicity. This phase 2 study evaluated the efficacy and safety of the PLD-containing CHOP regimen in newly diagnosed patients with aggressive peripheral T-cell lymphomas (PTCL). METHODS: Patients received PLD, cyclophosphamide, vincristine/vindesine, plus prednisone every 3 weeks for up to 6 cycles. The primary endpoint was the objective response rate at the end of treatment (EOT). RESULTS: From September 2015 to January 2017, 40 patients were treated. At the EOT, objective response was achieved by 82.5% of patients, with 62.5% complete response. As of the cutoff date (September 26, 2023), median progression-free survival (mPFS) and overall survival (mOS) were not reached (NR). The 2-year, 5-year, and 8-year PFS rates were 55.1%, 52.0%, and 52.0%. OS rate was 80.0% at 2 years, 62.5% at 5 years, and 54.3% at 8 years. Patients with progression of disease within 24 months (POD24) had worse prognosis than those without POD24, regarding mOS (41.2 months vs NR), 5-year OS (33.3% vs 94.4%), and 8-year OS (13.3% vs 94.4%). Common grade 3-4 adverse events were neutropenia (87.5%), leukopenia (80.0%), anemia (17.5%), and pneumonitis (17.5%). CONCLUSION: This combination had long-term benefits and manageable tolerability, particularly with less cardiotoxicity, for aggressive PTCL, which might provide a favorable benefit-risk balance. CLINICALTRIALS.GOV IDENTIFIER: Chinese Clinical Trial Registry, ChiCTR2100054588; IRB Approved: Ethics committee of Fudan University Shanghai Cancer Center (Date 2015.8.31/No. 1508151-13.
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Iridium-based electrocatalysts remain the only practical anode catalysts for proton exchange membrane (PEM) water electrolysis, due to their excellent stability under acidic oxygen evolution reaction (OER), but are greatly limited by their high cost and low reserves. Here, we report a nickel-stabilized, ruthenium dioxide (Ni-RuO2) catalyst, a promising alternative to iridium, with high activity and durability in acidic OER for PEM water electrolysis. While pristine RuO2 showed poor acidic OER stability and degraded within a short period of continuous operation, the incorporation of Ni greatly stabilized the RuO2 lattice and extended its durability by more than one order of magnitude. When applied to the anode of a PEM water electrolyser, our Ni-RuO2 catalyst demonstrated >1,000 h stability under a water-splitting current of 200 mA cm-2, suggesting potential for practical applications. Density functional theory studies, coupled with operando differential electrochemical mass spectroscopy analysis, confirmed the adsorbate-evolving mechanism on Ni-RuO2, as well as the critical role of Ni dopants in stabilization of surface Ru and subsurface oxygen for improved OER durability.
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OBJECTIVES: To compare the long-term oncologic outcomes of nipple-sparing mastectomy (NSM) with those of conventional mastectomy (CM) in patients with locally advanced breast cancer (LABC) receiving neoadjuvant chemotherapy (NACT). SUMMARY OF BACKGROUND DATA: NSM has been increasingly implemented in patients with breast cancer. However, oncologic efficacy of NSM in patients with LABC has not been sufficiently demonstrated. METHODS: The study group comprised 850 patients with clinical stage IIB to IIIC breast cancer who underwent NACT followed by either NSM and immediate breast reconstruction or CM alone. After propensity score-matching, 418 patients were included in the analysis. Local recurrence-free survival, disease-free survival (DFS), distant metastasis-free survival, and overall survival (OS) rates were calculated using the Kaplan-Meier method and compared using log-rank tests between the NSM and CM groups. RESULTS: After matching, the mean follow-up period was 70 ± 25 months for the NSM group and 74 ± 27 months for the CM group ( P = 0.181). There were no significant differences between the groups in terms of 6-year local recurrence-free survival (91.6% vs. 95.8%; P = 0.239), DFS (70.5% vs. 73.4%; P = 0.583), distant metastasis-free survival (79.8% vs. 77.4%; P = 0.320), or OS (87.6% vs. 84.8%; P = 0.465) rates. Additionally, we identified 30 patients in the NSM group who initially presented with tumor extension in the subareolar area; the nipple-areola complex was successfully preserved after NACT, and no recurrence at the nipple was observed in these patients. CONCLUSIONS: In this matched control study, we demonstrated comparable long-term oncologic outcomes between NSM with immediate reconstruction and CM alone after NACT for LABC. In patients who had tumors extending to the subareolar area before NACT, NSM can be tried if tumor involvement of the nipple-areola complex appears resolved on imaging studies after chemotherapy.
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Neoplasias de la Mama , Mamoplastia , Neoplasias de la Mama/patología , Femenino , Humanos , Mamoplastia/métodos , Mastectomía/métodos , Recurrencia Local de Neoplasia/patología , Pezones/cirugía , Tratamientos Conservadores del Órgano/métodos , Puntaje de Propensión , Estudios RetrospectivosRESUMEN
PURPOSE: A large proportion of patients with breast cancer who had mastectomy had undergone breast reconstruction with implants or autologous flaps. However, only a few studies have compared the breast cancer outcomes between the implant-based reconstruction (IBR) and autologous flap reconstruction (AFR). In this study, we retrospectively compared the local recurrence rates, distant metastasis rates, and survival outcomes between immediate IBR and AFR. METHODS: A total of 1530 patients with primary breast cancer who underwent IBR or AFR with nipple-/skin-sparing mastectomy were included. Patients who underwent neoadjuvant systemic therapy were excluded from the study. After propensity score matching by age at diagnosis, T stage, N stage, molecular subtype, mastectomy type, adjuvant radiotherapy status, and follow-up period, 938 patients were 1:1 matched, comprising the well-balanced IBR and AFR groups. Locoregional recurrence-free survival (LRRFS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and breast cancer-specific survival (BCSS) were compared between the matched groups. RESULTS: After matching, the median follow-up periods were 68 months and 71 months for the IBR and AFR groups, respectively. No significant differences were observed between the IBR and AFR groups regarding the local recurrence (7.2% vs. 5.1%; P = 0.175), regional recurrence (2.1% vs. 1.5%; P = 0.463), or distant metastasis (3.2% vs. 3.2%; P = 1.000) rates. Moreover, no significant difference was observed between the IBR and AFR groups in the LRRFS (hazard ratio, 0.691; 95% CI, 0.433-1.102; P = 0.118), DFS (hazard ratio, 0.709; 95% CI, 0.468-1.076; P = 0.104), DMFS (hazard ratio, 1.006; 95% CI, 0.491-2.059; P = 0.987), or BCSS (hazard ratio, 0.445; 95% CI, 0.111-1.786; P = 0.659). CONCLUSION: In this propensity score-matched analysis of oncologic outcomes in patients with primary breast cancer who underwent immediate breast reconstruction with nipple-/skin-sparing mastectomy, no significant differences were observed between the IBR and AFR groups.
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Implantes de Mama , Neoplasias de la Mama , Mamoplastia , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mastectomía , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/cirugía , Puntaje de Propensión , Estudios RetrospectivosRESUMEN
BACKGROUND: Oncologic safety of postmastectomy breast reconstruction in young women with breast cancer is not well-defined, especially in the setting of neoadjuvant chemotherapy (NACT). We retrospectively compared the oncologic outcomes following nipple-sparing (NSM)/skin-sparing mastectomy (SSM) with immediate breast reconstruction (IBR) and conventional mastectomy (CM) alone in young breast cancer patients after NACT. METHODS: A total of 1266 women with primary breast cancer who underwent NACT followed by total mastectomy with or without IBR were reviewed. Of these, only young patients (age ≤ 40 years at diagnosis) were included in the outcome analysis (n = 375). After propensity score-matching by clinical T and N stage, molecular subtype, response to NACT, and adjuvant radiotherapy status, 228 patients were 1:1 matched, comprising balanced IBR group (with NSM/SSM) and CM-alone group. RESULTS: The 5-year locoregional recurrence-free, disease-free, distant metastasis (DM)-free, and breast cancer-specific survival (BCSS) rates for the entire cohort of young patients were 83.4%, 65.3%, 71.7%, and 85.4%, respectively. Locoregional recurrence rates between the matched groups were similar (14% vs. 15.8%; p = 0.710); however, IBR group had significantly lower DM rate (27.2% vs. 40.4%; p = 0.036) and breast cancer mortality (14.9% vs. 27.2%; p = 0.023) than CM-alone group. IBR group showed significantly improved 5-year DM-free survival (74.1% vs. 62.6%; p = 0.043) and BCSS (89.1% vs. 77.6%; p = 0.048) rates than CM-alone group. CONCLUSIONS: Our results indicated that IBR with NSM/SSM does not negatively affect long-term oncologic outcomes compared to CM alone in young women with breast cancer receiving NACT.
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Neoplasias de la Mama , Mamoplastia , Adulto , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mastectomía , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/cirugía , Estudios RetrospectivosRESUMEN
BACKGROUND: Minimal change disease (MCD) is a common cause of the nephrotic syndrome. Several studies have shown an increased incidence of cancer in patients with MCD. However, there are no reports on the association between MCD and gastrointestinal stromal tumor (GIST). CASE PRESENTATION: We report a case of a 66-year-old female with severe nephrotic syndrome and concomitant duodenal GIST. Immunoglobulin test showed a significant increase of IgE levels. The diagnosis of renal histopathology was MCD with subacute tubulointerstitial injury. The combination of preoperative Imatinib mesylate chemotherapy and tumor excision was accompanied by significant remission of proteinuria, and IgE level decreasing, without immunosuppressivetherapy. CONCLUSIONS: It is the first case report that MCD was associated with GIST and elevated IgE level. Clinically, in patients with elevated IgE level associated with nephrotic syndrome, the possibility of tumor must be taken into account when allergic factors are excluded.
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Tumores del Estroma Gastrointestinal , Nefrosis Lipoidea , Síndrome Nefrótico , Anciano , Femenino , Tumores del Estroma Gastrointestinal/complicaciones , Humanos , Inmunoglobulina E , Riñón/patología , Nefrosis Lipoidea/complicaciones , Nefrosis Lipoidea/diagnóstico , Nefrosis Lipoidea/tratamiento farmacológico , Síndrome Nefrótico/complicacionesRESUMEN
OBJECTIVES: To evaluate the oncologic outcomes and risk factors for locoregional recurrence (LRR) and nipple-areola complex recurrence (NR) in a large series of breast cancer patients who underwent nipple-sparing mastectomy (NSM) and immediate reconstruction after neoadjuvant chemotherapy (NACT). SUMMARY OF BACKGROUND DATA: The use of NSM and immediate reconstruction in breast cancer patients receiving NACT is increasing. However, the oncologic safety of this approach is unclear. PATIENTS AND METHODS: A total of 310 breast cancer patients (319 breasts) who underwent NACT and NSM between February 2010 and November 2016 were retrospectively analyzed. Clinical and pathologic factors associated with increased risks of LRR and NR were analyzed using univariate (Chi-square or Fisher exact test) and multivariate (Cox proportional hazard regression model) analyses. RESULTS: During a mean follow-up of 63 ± 22 months, 38 cases had LRR as the first event, including 6 cases of NR as the first event. The 5-year cumulative LRR and NR rates were 11.0% and 1.9%, respectively. In univariate analysis, clinical T stage, pathologic nodal status, histologic grade, lymphovascular invasion, and post-NACT Ki67 status were associated with increased LRR risk, and post-NACT Ki67 status was the only significant risk factor for NR. In multivariate analysis, post-NACT Ki67 ≥10% (hazard ratio, 4.245; 95% confidence interval, 1.865-9.663; P = 0.001) was an independent risk factor for LRR. CONCLUSIONS: NSM and immediate reconstruction seem to be oncologically safe with acceptable LRR and NR rates for appropriately selected breast cancer patients treated with NACT. Post-NACT Ki67 ≥10% was associated with increased risk of LRR or NR, and therefore, necessitates cautious follow-up.
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Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Mamoplastia/métodos , Mastectomía/métodos , Adulto , Quimioterapia Adyuvante , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia , Pezones , Tratamientos Conservadores del Órgano , Factores de Riesgo , Tasa de SupervivenciaRESUMEN
PURPOSE: We compared oncologic outcomes between breast cancer patients who underwent immediate implant-based breast reconstruction (IBBR) and those who underwent autologous flap reconstruction (AFR) after neoadjuvant chemotherapy (NACT). METHODS: The study group comprised 536 patients with primary breast cancer who underwent NACT followed by immediate IBBR or AFR. After propensity score matching, 138 patients in the IBBR group and 276 patients in the AFR group were selected for comparisons of locoregional recurrence-free survival (LRRFS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and breast cancer-specific survival (BCSS). RESULTS: No significant differences were observed between the matched groups in locoregional recurrence rates (IBBR vs. AFR: 12.3% vs. 12%; P = 0.915) and distant metastasis (13% vs. 17%; P = 0.293). There was also no significant difference between the groups in LRRFS (P = 0.956), DFS (P = 0.606), DMFS (P = 0.283), or BCSS (P = 0.121). The 5- and 10-year LRRFS rates were 87.6% and 85.9% in the IBBR group, and 87.7% and 86.1% in the AFR group; the 5- and 10-year DFS rates were 79% and 77.5% in the IBBR group, and 77% and 75% in the AFR group; the 5- and 10-year DMFS rates were 85.9% and 85.9% in the IBBR group, and 83.2% and 81.8% in the AFR group; and the 5- and 10-year BCSS rates were 97.8% and 91.3% in the IBBR group, and 91.8% and 86% in the AFR group, respectively. CONCLUSIONS: In this propensity score-matched analysis of oncologic outcomes in breast cancer patients who underwent immediate reconstruction after NACT, no significant differences were observed between the IBBR and AFR groups.
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Neoplasias de la Mama , Mamoplastia , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mastectomía , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/cirugía , Puntaje de PropensiónRESUMEN
BACKGROUND: A short tumor-to-nipple distance (TND) is reported as a strong predictor of nipple-areola complex (NAC) involvement. Eligibility for nipple-sparing mastectomy (NSM) remains controversial, especially regarding TND. In this study, we compared long-term oncologic outcomes after NSM between patients with a TND ≤ 1 cm and those with a TND > 1 cm. METHODS: Overall, 1369 patients with primary breast cancer who underwent NSM with immediate reconstruction from March 2003 to December 2015 were included for analysis. After propensity score matching, 495 patients with a TND ≤ 1 cm (group A) and 495 patients with a TND > 1 cm (group B) on imaging were selected to compare long-term oncologic outcomes. RESULTS: After matching, the median follow-up periods for surviving patients were 109 months and 112 months for groups A and B, respectively. There were no significant differences between groups with respect to the 5-year cumulative local recurrence (8.1% vs. 6.3%; p = 0.268), NAC recurrence (5.1% vs. 2.8%; p = 0.072), regional recurrence (2.0% vs. 3.6%; p = 0.125), or distant recurrence (5.9% vs. 4.8%; p = 0.480) rates. Furthermore, no significant differences were observed between the groups with respect to the 10-year local recurrence-free survival (87.1% vs. 90.7%; p = 0.164) or disease-free survival (77.9% vs. 81.6%; p = 0.222) rates. CONCLUSIONS: A preoperative TND ≤ 1 cm on imaging should not be contraindicated to NSM as long as there is no involvement of NAC clinically or on imaging and if retroareolar margins are confirmed to be negative for tumor cells.
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Neoplasias de la Mama , Mamoplastia , Neoplasias de la Mama/cirugía , Estudios de Cohortes , Femenino , Humanos , Mastectomía , Recurrencia Local de Neoplasia/cirugía , Pezones/cirugía , Estudios RetrospectivosRESUMEN
With the development of the internet, applications have become complicated, and the relevant technology has diversified. Compared with medical applications, the significance of information technology has been expanding to include clinical auxiliary functions of medical information. This includes electronic medical records, electronic prescriptions, medical information systems, etc. Although research on the data processing structure and format of various related systems is becoming mature, the integration is insufficient. An integrated medical information system with security policy and privacy protection, which combines e-patient records, e-prescriptions, modified smart cards, and fingerprint identification systems, and applies proxy signature and group signature, is proposed in this study. This system effectively applies and saves medical resources-satisfying the mobility of medical records, presenting the function, and security of medicine collection, and avoiding medical conflicts and profiteering to further acquire the maximum effectiveness with the least resources. In this way, this medical information system may be developed into a comprehensive function that eliminates the transmission of manual documents and maintains the safety of patient medical information. It can improve the quality of medical care and indispensable infrastructure for medical management.
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Seguridad Computacional , Registros Electrónicos de Salud , Privacidad , Confidencialidad , Electrónica , Humanos , Sistemas de Información , PolíticasRESUMEN
BACKGROUND: Nipple-sparing mastectomy (NSM) has become increasingly prevalent for patients with ductal carcinoma in situ (DCIS) requiring mastectomy. However, few data regarding recurrence outcomes after NSM are available for this patient population. This study evaluated the locoregional recurrence (LRR) rate for patients with pure DCIS who underwent NSM followed by immediate breast reconstruction without adjuvant radiotherapy and investigated potential risk factors for LRR and/or nipple-areola complex recurrence (NR). METHODS: A retrospective chart review was performed for 199 consecutive patients with pure DCIS who underwent NSM and immediate breast reconstruction between March 2003 and December 2015. Risk factors for LRR and NR were analyzed using univariate (Chi square test) and multivariate (Cox model) methods. RESULTS: The median follow-up duration after surgery was 97 months (range, 39-186 months). At 10 years, the LRR rate was 4.5%, and the NR rate was 3%. The univariate analysis showed that high nuclear grade, negative receptor status, positive human epidermal growth factor receptor 2 (HER2) status, and negative hormone receptor/positive HER2 subtype were associated with increased risk for NR. The multivariate analysis demonstrated that negative progesterone receptor status was an independent risk factor for LRR. However, margin status and tumor-to-nipple distance (TND) were not associated with increased risk for either LRR or NR. CONCLUSIONS: The study findings suggest that NSM can be a feasible surgical option even for DCIS with a TND of 1 cm or less if the retroareolar resection margin is negative for malignancy. Determining the molecular subtype of DCIS might be helpful in identifying patients at high risk for recurrence.
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Neoplasias de la Mama/cirugía , Carcinoma Intraductal no Infiltrante/cirugía , Mamoplastia/métodos , Mastectomía Subcutánea/métodos , Pezones/cirugía , Adulto , Anciano , Implantes de Mama , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Carcinoma Intraductal no Infiltrante/mortalidad , Carcinoma Intraductal no Infiltrante/patología , Femenino , Humanos , Márgenes de Escisión , Mastectomía Subcutánea/efectos adversos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Tratamientos Conservadores del Órgano/métodos , República de Corea , Estudios Retrospectivos , Análisis de Supervivencia , Adulto JovenRESUMEN
Coking wastewater is highly concentrated and extremely toxic, greatly challenging the treatment technologies. Conventional biological technology such as anaerobic-anoxic-oxic (A2O) system is inefficient, since various biological reactions are inhibited by toxicants in coking wastewater. In this work, a pilot-scale three-dimensional electrochemical reactor (3DER) is integrated into the A2O system as a pretreatment unit to improve the treatment efficiency of coking wastewater. The results indicate that 3DER pretreatment increased the biodegradability of coking wastewater, promoting the degradation of coking wastewater in A2O system. The integrated 3DER-A2O system can remove 94.4% of COD and 76.2% of TN from coking wastewater, and the energy consumption was only 0.22 kWh/kg COD and 4.69 kWh/kg TN. The components of coking wastewater were significantly simplified and the acute toxicity was reduced from 99% to 12% after the treatment. The integrated 3DER-A2O system provides a new solution for coking wastewater treatment, showing a promising application potential.
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Coque , Aguas Residuales , Anaerobiosis , Reactores Biológicos , Eliminación de Residuos LíquidosRESUMEN
"Education Cloud" is a cloud-computing application used in educational contexts to facilitate the use of comprehensive digital technologies and establish data-based learning environments. The immense amount of digital resources, data, and teaching materials involved in these environments must be stored in robust data-access systems. These systems must be equipped with effective security mechanisms to guarantee confidentiality and ensure the integrity of the cloud-computing environment. To minimize the potential risk of privacy exposure, digital sharing service providers must encrypt their digital resources, data, and teaching materials, and digital-resource owners must have complete control over what data or materials they share. In addition, the data in these systems must be accessible to e-learners. In other words, data-access systems should not only encrypt data, but also provide access control mechanisms by which users may access the data. In cloud environments, digital sharing systems no longer target single users, and the access control by numerous users may overload a system and increase management burden and complexity. This study addressed these challenges to create a system that preserves the benefits of combining digital sharing systems and cloud computing. A cloud-based and learner-centered access control mechanism suitable for multi-user digital sharing was developed. The proposed mechanism resolves the problems concerning multi-user access requests in cloud environments and dynamic updating in digital-sharing systems, thereby reducing the complexity of security management.
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OBJECTIVE: To assess changes in the cognitive function and hippocampal ultrastructure of elderly rats exposed to sevoflurane. METHODS: Ault male Sprague-Dawley rats were given subcutaneous injection of D-galactose on the neck for 40 d to establish elderly models, after 9-day behavioral training. The model rats were divided into 3 groups randomly: control group with natural air, A/O group with 6 h exposure to carrier gas (2 L/min Air+2 L/min O2), and Sev group with 6 h exposure to 3.2% sevoflurane through carrier gas. Morris Water Maze and balance beam experiment were conducted on 6 rats in each group 2 h, 1 week and 4 weeks after treatments, respectively. The hippocampal tissues of the rats were rapidly dissected and prepared by glutaraldehyde fixation, ethanol dehydration, infiltration, embedding polymerization, semimembrane section localization and staining for examinations under transmission electron microscopy. The hippocampal ultrastructure such as nucleus, cytoplasm, mitochondria, endoplasmic reticulum, medullary nerve fiber, synapse and apoptotic corpuscle were observed. RESULTS: Ethology: compared with the control and A/O groups, significant reductions in the probe trial capability were found in the rats after 2 h exposure to sevoflurane, which recovered at 1 week and 4 weeks. Sevoflurane also increased the working memory escape latency 2 h and 1 week after exposure. The balance beam experiment showed that sevoflurane prolonged the staring time of rats after 2 h exposure, which recovered at 1 week and 4 weeks. Prolonged length for going through the balance beam was found consistently in the rats exposed to sevoflurane. Transmission electron microscopy: rats in the control group were found to have clear hippocampal ultrastructure, intact nuclear membrane, no edema fluid in the cytoplasm, intact mitochondria and endoplasmic reticulum, normal medullary nerve fibers, intact synaptic structure, and no apoptotic bodies in the cells. But a small amount of edema were observed in the cytoplasm of hippocampal cells in the rats exposed to sevoflurane and A/O at 2 h, which increased at 1 week. The cytoplasmic morphology of rats in the A/O group returned to normal at 4 weeks. But further increase of edema was observed in the rats 4 weeks after exposure to sevoflurane. No abnormal morphological structures or apoptotic bodies in other organelles were found. CONCLUSIONS: Sevoflurane can induce early neurocognitive impairments in elderly rats, which may be related with changes in the hippocampus ultrastructure.
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Envejecimiento , Cognición , Hipocampo/ultraestructura , Sevoflurano/farmacología , Animales , Hipocampo/efectos de los fármacos , Masculino , Aprendizaje por Laberinto , Distribución Aleatoria , Ratas , Ratas Sprague-DawleyRESUMEN
BACKGROUND/AIMS: Spinal dorsal horn (SDH) is one of the most important regions for analgesia produced by endomorphin-2 (EM2), which has a higher affinity and specificity for the µ-opioid receptor (MOR) than morphine. Many studies have focused on substantia gelatinosa (SG, lamina II) neurons to elucidate the cellular basis for its antinociceptive effects. However, the complicated types and local circuits of interneurons in the SG make it difficult to understand the real effects of EM2. Therefore, in the present study, we examined the effects of EM2 on projection neurons (PNs) in lamina I. METHODS: Tracing, immunofluoresence, and immunoelectron methods were used to examine the morphological connections between EM2-immunoreactive (-ir) terminals and PNs. By using in vitro whole cell patch clamp recording technique, we investigated the functional effects of EM2 on PNs. RESULTS: EM2-ir afferent terminals directly contacted PNs projecting to the parabrachial nucleus in lamina I. Their synaptic connections were further confirmed by immunoelectron microscopy, most of which were asymmetric synapses. It was found that EM2 had a strong inhibitory effect on the frequency, but not amplitude, of the spontaneous excitatory postsynaptic current (sEPSC) of the spinoparabrachial PNs in lamina I, which could be reversed by MOR antagonist CTOP. However, their spontaneous inhibitory postsynaptic current (sIPSC) and intrinsic properties were not changed after EM2 application. CONCLUSION: Applying EM2 to the SDH could produce analgesia through inhibiting the activities of the spinoparabrachial PNs in lamina I by reducing presynaptic neurotransmitters release from the primary afferent terminals.
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Carbon aerogels that are typically prepared using sol-gel chemistry have unique three dimensional networks of interconnected nanometer-sized particles and thus exhibit many fascinating physical properties and great application potentials in widespread fields. To boost the practical applications, it is necessary to develop efficient and low-cost methods to produce high-performance carbon aerogels on a large-scale, preferably in a sustainable way. In 2012, two new classes of aerogels consisting of carbon-nanofiber (CNF) networks were prepared from biomass-derived precursors by chemosynthesis (i.e. template-directed hydrothermal carbonization of carbohydrate) and biosynthesis (i.e. use of bacterial cellulose as precursor), respectively. This Review gives a critical overview of this emerging and rapidly developing field, focusing on the synthetic strategies of the carbon-nanofiber aerogels and their outstanding physical properties. We also discuss the multifunctional application potentials of the two sorts of carbon aerogels and their nanocomposites, and highlight the challenges and future opportunities in this field.
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Carbono , Nanofibras/química , Carbono/química , Carbono/metabolismo , Geles/química , Geles/metabolismoRESUMEN
Carbon aerogels with 3D networks of interconnected nanometer-sized particles exhibit fascinating physical properties and show great application potential. Efficient and sustainable methods are required to produce high-performance carbon aerogels on a large scale to boost their practical applications. An economical and sustainable method is now developed for the synthesis of ultrathin carbon nanofiber (CNF) aerogels from the wood-based nanofibrillated cellulose (NFC) aerogels via a catalytic pyrolysis process, which guarantees high carbon residual and well maintenance of the nanofibrous morphology during thermal decomposition of the NFC aerogels. The wood-derived CNF aerogels exhibit excellent electrical conductivity, a large surface area, and potential as a binder-free electrode material for supercapacitors. The results suggest great promise in developing new families of carbon aerogels based on the controlled pyrolysis of economical and sustainable nanostructured precursors.
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Nanostructured carbon aerogels with outstanding physicochemical properties have exhibited great application potentials in widespread fields and therefore attracted extensive attentions recently. It is still a challenge so far to develop flexible and economical routes to fabricate high-performance nanocarbon aerogels, preferably based on renewable resources. Here, ultralight and multifunctional reduced graphene oxide/carbon nanofiber (RGO/CNF) aerogels are fabricated from graphene oxide and low-cost, industrially produced bacterial cellulose by a three-step process of freeze-casting, freeze-drying, and pyrolysis. The prepared RGO/CNF aerogel possesses a very low apparent density in the range of 0.7-10.2 mg cm-3 and a high porosity up to 99%, as well as a mechanically robust and electrically conductive 3D network structure, which makes it to be an excellent candidate as absorber for oil clean-up and an ideal platform for constructing flexible and stretchable conductors.
Asunto(s)
Carbono/química , Celulosa/química , Grafito/químicaRESUMEN
Three dimensional (3D) carbon nanomaterials exhibit great application potential in environmental protection, electrochemical energy storage and conversion, catalysis, polymer science, and advanced sensors fields. Current methods for preparing 3D carbon nanomaterials, for example, carbonization of organogels, chemical vapor deposition, and self-assembly of nanocarbon building blocks, inevitably involve some drawbacks, such as expensive and toxic precursors, complex equipment and technological requirements, and low production ability. From the viewpoint of practical application, it is highly desirable to develop a simple, cheap, and environmentally friendly way for fabricating 3D carbon nanomaterials in large scale. On the other hand, in order to extend the application scope and improve the performance of 3D carbon nanomaterials, we should explore efficient strategies to prepare diverse functional nanomaterials based on their 3D carbon structure. Recently, many researchers tend to fabricate high-performance 3D carbon-based nanomaterials from biomass, which is low cost, easy to obtain, and nontoxic to humans. Bacterial cellulose (BC), a typical biomass material, has long been used as the raw material of nata-de-coco (an indigenous dessert food of the Philippines). It consists of a polysaccharide with a ß-1,4-glycosidic linkage and has a interconnected 3D porous network structure. Interestingly, the network is made up of a random assembly of cellulose nanofibers, which have a high aspect ratio with a diameter of 20-100 nm. As a result, BC has a high specific surface area. Additionally, BC hydrogels can be produced on an industrial scale via a microbial fermentation process at a very low price. Thus, it can be an ideal platform for design of 3D carbon-based functional nanomaterials. Before our work, no systematic work and summary on this topic had been reported. This Account presents the concepts and strategies of our studies on BC in the past few years, that is, converting cheap biomass into high value-added 3D carbon nanomaterials and designing diverse functional materials on 3D carbon structure. We first briefly introduce the history, constituent, and microstructure features of BC and discuss its advantages as a raw material for preparing the CNF aerogels. Then, we summarize the methods and strategies for preparing various 3D carbon-based nanomaterials from BC. In addition, the potential applications of the developed CNF aerogel based functional materials are also highlighted in this Account, including stretchable conductors, oxygen reduction reaction catalysts, supercapacitors, lithium-ion battery, and oil cleanup. Finally, we give some prospects on the future challenges in this emerging research area of designing CNF aerogel based functional nanomaterials from BC.