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1.
J Physiol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953534

RESUMO

The central histaminergic system has a pivotal role in emotional regulation and psychiatric disorders, including anxiety, depression and schizophrenia. However, the effect of histamine on neuronal activity of the centrolateral amygdala (CeL), an essential node for fear and anxiety processing, remains unknown. Here, using immunostaining and whole-cell patch clamp recording combined with optogenetic manipulation of histaminergic terminals in CeL slices prepared from histidine decarboxylase (HDC)-Cre rats, we show that histamine selectively suppresses excitatory synaptic transmissions, including glutamatergic transmission from the basolateral amygdala, on both PKC-δ- and SOM-positive CeL neurons. The histamine-induced effect is mediated by H3 receptors expressed on VGLUT1-/VGLUT2-positive presynaptic terminals in CeL. Furthermore, optoactivation of histaminergic afferent terminals from the hypothalamic tuberomammillary nucleus (TMN) also significantly suppresses glutamatergic transmissions in CeL via H3 receptors. Histamine neither modulates inhibitory synaptic transmission by presynaptic H3 receptors nor directly excites CeL neurons by postsynaptic H1, H2 or H4 receptors. These results suggest that histaminergic afferent inputs and presynaptic H3 heteroreceptors may hold a critical position in balancing excitatory and inhibitory synaptic transmissions in CeL by selective modulation of glutamatergic drive, which may not only account for the pathophysiology of psychiatric disorders but also provide potential psychotherapeutic targets. KEY POINTS: Histamine selectively suppresses the excitatory, rather than inhibitory, synaptic transmissions on both PKC-δ- and SOM-positive neurons in the centrolateral amygdala (CeL). H3 receptors expressed on VGLUT1- or VGLUT2-positive afferent terminals mediate the suppression of histamine on glutamatergic synaptic transmission in CeL. Optogenetic activation of hypothalamic tuberomammillary nucleus (TMN)-CeL histaminergic projections inhibits glutamatergic transmission in CeL via H3 receptors.

2.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1705-1716, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812183

RESUMO

Traditional Chinese medicine proteins(TCMPs) not only have nutritional values and biological activities but also serve as key enzymes in the synthesis of pharmacodynamic components in traditional Chinese medicines. They play a role in the synthesis of pharmacodynamic components by regulating biosynthesis and selective synthesis pathways and controlling drug quality and stability. The recent years have witnessed great progress in the research on the structures and functions of proteins using various methods and technologies. However, the research on the structures and functions of TCMPs lags behind. Therefore, it is urgent to study the structures and functions of TCMPs using modern means to promote the discovery of innovative drugs based on TCMPs and clarify the synthesis pathways of pharmacodynamic components. This study introduces the latest techniques for studying protein structures and functions, including spectroscopy, mass spectrometry, nuclear magnetic resonance, X-ray crystal diffraction, microscopy, and structure prediction. Furthermore, this paper introduces the methods for protein functional studies, including liquid chromatography-mass spectrometry, co-immunoprecipitation, yeast two-hybrid, and pull-down assay. By systematically reviewing these techniques and methods, this paper provides technical references for the structural identification and functional studies of TCMPs, with the aim of promoting the in-depth exploration of the structures and functions of TCMPs.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/química , Proteínas/química , Proteínas/metabolismo , Humanos , Espectrometria de Massas
3.
Fa Yi Xue Za Zhi ; 40(3): 261-268, 2024 Jun 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-39166307

RESUMO

OBJECTIVES: To explore the association between violent behaviors and emotions in individuals with mental disorders, to evaluate the application value of facial expression analysis technology in violence risk assessment of individuals with mental disorders in supervised settings, and to provide a reference for violence risk assessment. METHODS: Thirty-nine male individuals with mental disorders in supervised settings were selected, the participant risk of violence, cognitive function, psychiatric symptoms and severity were assessed using the Modified Overt Aggression Scale (MOAS), the Historical, Clinical, Risk Management-Chinese version(HCR-CV), the Positive and Negative Syndrome Scale (PANSS) and the Brief Psychiatric Rating Scale (BPRS). An emotional arousal was performed on the participants and the intensity of their emotions and facial expression action units was recorded before, during and after the arousal. One-way analysis of variance (ANOVA) was used to compare the differences in the intensity of emotions and facial expression action units before, during and after the arousal. Pearson correlation analysis was used to calculate the correlations between the intensity of the seven basic emotional facial expressions and the scores of the assessment scales. RESULTS: The intensity difference of sadness, surprise and fear in different time periods was statistically significant (P<0.05). The intensity of the left medial eyebrow lift action unit was found significantly different before and after the emotional arousal (P<0.05). The intensity of anger was positively correlated with the Modified Overt Aggression Scale score throughout the experiment (P<0.05). CONCLUSIONS: Eye action units such as eyebrow lifting, eyelid tightening and upper eyelid lifting can be used as effective action units to identify sadness, anger and other negative emotions associated with violent behaviors. Facial expression analysis technology can be used as an auxiliary tool to assess the potential risk of violence in individuals with mental disorders in supervised settings.


Assuntos
Agressão , Emoções , Expressão Facial , Transtornos Mentais , Violência , Humanos , Masculino , Adulto , Violência/psicologia , Medição de Risco/métodos , Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia , Adulto Jovem , Agressão/psicologia , Escalas de Graduação Psiquiátrica , Nível de Alerta/fisiologia , Psiquiatria Legal/métodos , Pessoa de Meia-Idade , Análise de Variância
4.
Environ Sci Technol ; 57(23): 8506-8513, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37267077

RESUMO

The widespread use of plastic products leads to the ubiquity of microplastics in daily life, while the release of microplastics from long-used contact lenses has not been reported due to the limitations of conventional detection methods. Here, we established a new and rapid method to capture and count microplastics by using a high-content screening system. This method can simultaneously measure the diameter, area, and shape of each plastic particle, and the reliability and applicability of this method were verified with commercial microplastics. It is estimated that 90,698 particles of microplastics could be released from a pair of contact lenses during a year of wearing. The microplastics in the leachates were confirmed to be released from the contact lenses by scanning electron microscopy and Fourier transform infrared spectroscopy fingerprint analysis. Our study reveals an undiscovered pathway of microplastic direct exposure to humans, highlighting the urgent need to assess the potential health risks caused by eye exposure to microplastics.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Plásticos/análise , Luz Solar , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise , Monitoramento Ambiental
5.
J Gastroenterol Hepatol ; 38(6): 883-887, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36409289

RESUMO

BACKGROUND: During endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), cytopathology with rapid on-site evaluation (ROSE) can improve diagnostic yield and accuracy. However, ROSE is unavailable in most Asian and European institutions because of the shortage of cytopathologists. Therefore, developing computer-assisted diagnostic tools to replace manual ROSE is crucial. Herein, we reported the validation of an artificial intelligence (AI)-based model (ROSE-AI model) to substitute manual ROSE during EUS-FNA. METHODS: A total of 467 digitized images from Diff-Quik (D&F)-stained EUS-FNA slides were divided into training (3642 tiles from 367 images) and internal validation (916 tiles from 100 images) datasets. The ROSE-AI model was trained and validated using training and internal validation datasets, respectively. The specificity was emphasized while developing the model. Then, we evaluated the AI model on a 693-image external dataset. We assessed the performance of the AI model to detect cancer cells (CCs) regarding the accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS: The ROSE-AI model achieved an accuracy of 83.4% in the internal validation dataset and 88.7% in the external test dataset. The sensitivity and PPV were 79.1% and 71.7% in internal validation dataset and 78.0% and 60.7% in external test dataset, respectively. CONCLUSION: We provided a proof of concept that AI can be used to replace manual ROSE during EUS-FNA. The ROSE-AI model can address the shortage of cytopathologists and make ROSE available in more institutes.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Neoplasias Pancreáticas , Humanos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Neoplasias Pancreáticas/patologia , Citologia , Avaliação Rápida no Local , Inteligência Artificial , Estudos Retrospectivos
6.
J Biochem Mol Toxicol ; 37(2): e23242, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36229953

RESUMO

The role of reactive oxygen species (ROS) is crucial for the pathogenesis of acute pancreatitis (AP). Proanthocyanidins (PAs) have been confirmed to exert antioxidant activity. Our study aimed to determine whether PAs alleviated SAP via reducing ROS, suppressing NLRP3 inflammasome, and inhibiting M1 macrophage polarization. Our study investigated the protective effects of PAs on pancreatic histopathological injury using SAP mice. The effects of PAs on macrophages were investigated in inflammatory RAW 264.7 cells or mouse bone marrow-derived macrophages (BMDMs) induced by lipopolysaccharide (LPS). Immunofluorescence staining and/or western blot assay were employed to evaluate NLRP3 inflammasome in macrophages and pancreatic tissue. Cell counting kit-8 (CCK-8) was used to access effects of PAs on cell viability and cytometry flow was used to determine the effects of the PAs on the ROS levels of the RAW 264.7 cells. Then, we evaluated M1 macrophage polarization using flow cytometry or real-time quantitative polymerase chain reaction (RT-qPCR). PAs administration alleviated pancreatic inflammation in SAP mice. The PAs depressed NLRP3 inflammasome and inhibited M1 macrophage polarization in pancreatic tissue. We also found that the PAs showed no cellular toxicity but decreased ROS levels in RAW 264.7 cells, downregulated the NLRP3 inflammasome in the macrophages, and inhibited cell M1 macrophage polarization. Our study indicates the anti-inflammatory properties of the PAs on SAP mice by decreasing ROS levels, suppressing NLRP3 inflammasome, and M1 macrophage polarization.


Assuntos
Pancreatite , Proantocianidinas , Camundongos , Animais , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proantocianidinas/farmacologia , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Espécies Reativas de Oxigênio , Doença Aguda , Macrófagos
7.
BMC Anesthesiol ; 23(1): 49, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755214

RESUMO

BACKGROUNDS: To preliminary evaluate the application of novel SaCoVLM video laryngeal mask -guided intubation for anesthetized children. METHODS: One hundred twenty-four children with microtia (ages 5-15 years,) who required general intubation anaesthesia, were enrolled in the study. After induction of general anesthesia,guided tracheal intubation under direct vision of the SaCoVLM was performed. Our primary outcome was first-pass success rate of guided tracheal tube placement. Secondary outcome included glottic visualization grades, the first-attempt success rate of LMA placement, the time for LMA placement and time to endotracheal intubation as well as the time for LMA removal after successful intubation, the fiberoptic grade of laryngeal view, the baseline and postinduction hemodynamic parameters were also recorded,and the incidence 24 h complications after operation. RESULTS: The first-pass success rate of guided tracheal tube placement was 91.1% (95%CI = 1.04-1.14), the status of glottic visualization was classified: grade 1 in 27cases, grade 2 in 36 cases, grade 3 in 41 cases and grade 4 in 20 cases. The first success rate of LMA placement was 92.7% (95%CI = 1.03-1.13), the time for LMA insertion was 15.7 (±9.1) s, intubation time was 30.9 (±17.6) s and withdrawl time was 24.9 (±9.3) s. The incidence of postoperative sore throat at 2 h was 29%, and 16.1% at 24 h, without dysphagia and hypoxia. CONCLUSION: The SaCoVLM video laryngeal mask-guided intubation is feasible in children, with a high success rate, could be a new promising device to guide intubation in airway management. TRIAL REGISTRATION: This study was approved by the University's Institutional Review Board and written informed consent was obtained from all subjects participating in the trial. The trial was registered prior to patient enrollment at clinicaltrials.gov (ChiCTR2200061481, http://www.chictr.org.cn . Principal investigator: Juan Zhi; Date of registration: 26/06/2022.


Assuntos
Máscaras Laríngeas , Faringite , Adolescente , Criança , Pré-Escolar , Humanos , Manuseio das Vias Aéreas , Anestesia Geral , Intubação Intratraqueal , Faringite/epidemiologia , Faringite/etiologia
8.
J Clin Monit Comput ; 37(3): 857-865, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36550347

RESUMO

The Ambu Aura-i laryngeal mask is considered to be a device for blind intubation as well as for fiberoptic guided intubation. The novel video laryngeal airway mask SaCoVLM is a supraglottic airway device that allows intubation under direct vision. We hypothesized that success rates for device placement and tracheal intubation with the SaCoVLM would be comparable with the Ambu Aura-i mask. A prospective, randomized clinical trial was conducted from March 2021 to December 2021. One hundred and twenty patients were enrolled and randomized in the study. Direct intubation was performed with the SaCoVLM, and fiberoptic guided intubation was performed with the Ambu Aura-i mask. The primary outcome measure was the first success rate of LMA placement. Secondary outcome measures were the time from device placement and time from endotracheal intubation (as well as the time for LMA removal after successful intubation), differences in airway leak pressure, fiberoptic grade of the laryngeal view, and incidence of blood staining. The first success rate of LMA placement was similar for the two devices. There was no difference in the time for successful endotracheal intubation between the Ambu Aura-i and SaCoVLM groups (24.1 s ± 6.3 versus 25.7 s ± 2.1; p > 0.05). The time for removal was slower in the SaCoVLM group than in the Ambu Aura-i group (20.8 s ± 0.8 versus 14.7 s ± 6.1; p < 0.01). The airway leak pressure was higher in the SaCoVLM group than in the Ambu Aura-i group (27.0 s ± 1.0 versus 22.3 s ± 3.6; p < 0.01), and the incidence of blood staining was higher in the SaCoVLM group (16.7%). The SaCoVLM has an overall comparable performance to the Ambu Aura-i mask. However, the SaCoVLM is better relative to direct intubation without the assistance of a flexible intubation scope, which reduces the device's demand.


Assuntos
Microtia Congênita , Epilepsia , Máscaras Laríngeas , Humanos , Criança , Estudos Prospectivos , Intubação Intratraqueal
9.
Appl Opt ; 61(30): 9069-9077, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36607036

RESUMO

A large number of certified samples are usually required to build models in the quantitative analysis of complicated matrices in laser-induced-breakdown spectroscopy (LIBS). Because of differences among instruments, including excitation and collection efficiencies, a quantitative model made on one instrument is difficult to apply directly to other instruments. Each instrument requires a large number of samples to model, which is very labor intensive and will hinder the rapid application of the LIBS technique. To eliminate the differences in spectral data from different instruments and reduce the cost of building new models, a piecewise direct standardization method combined with partial least squares (PLS_PDS) is studied in this work. Two portable LIBS instruments with the same configuration are used to obtain spectral data, one of which is called a master instrument because its calibration model is directly built on a large number of labeled samples, and the other of which is called a slave instrument because its model is obtained from the master instrument. The PLS_PDS method is used to build a transfer function of spectra between the master instrument and slave instrument to reduce the spectral difference between two instruments, and thus one calibration model can adapt to different instruments. Results show that for multiple elemental analyses of aluminium alloy samples, the number of samples required for slave modeling was reduced from 51 to 14 after model transferring by PLS_PDS, and the quantitative performance of the slave instrument was close to that of the master instrument. Therefore, the model transfer method can obviously reduce the sample number of building models for slave instruments, and it will be beneficial to advance the application of LIBS.

10.
Nano Lett ; 21(24): 10172-10177, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34865498

RESUMO

With continued scaling toward higher component densities, integrated circuits (ICs) contain ever greater lengths of nanowire that are vulnerable to failure via electromigration. Previously, plastic electromigration driven by the "electron wind" has been observed, but not the elastic response to the wind force itself. Here we describe mapping, via electron energy-loss spectroscopy, the density of a lithographically defined aluminum nanowire with sufficient precision to determine both its temperature and its internal pressure. An electrical current density of 108 A/cm2 produces Joule heating, tension upwind, and compression downwind. Surprisingly, the pressure returns to its ambient value well inside the wire, where the current density is still high. This spatial discrepancy points to physics that are not captured by a classical "wind force" model and to new opportunities for optimizing electromigration-resistant IC design.


Assuntos
Elétrons
11.
Angew Chem Int Ed Engl ; 61(29): e202204420, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35543248

RESUMO

Acinetobacter baumannii is currently posing a serious threat to global health. Lipopolysaccharide (LPS) is a potent virulence factor of pathogenic Gram-negative bacteria. To explore the antigenic properties of A. baumannii LPS, four Kdo-containing inner core glycans from A. baumannii strain ATCC 17904 were synthesized. A flexible and divergent method based on the use of the orthogonally substituted α-Kdo-(2→5)-Kdo disaccharides was developed. Selective removal of different protecting groups in these key precursors and elongation of sugar chain via α-stereocontrolled coupling with 5,7-O-di-tert-butylsilylene or 5-O-benzoyl protected Kdo thioglycosides and 2-azido-2-deoxyglucosyl thioglycoside allowed efficient assembly of the target molecules. Glycan microarray analysis of sera from infected patients revealed that the 4,5-branched Kdo trimer was a potential antigenic epitope, which is attractive for further immunological research to develop carbohydrate vaccines against A. baumannii.


Assuntos
Acinetobacter baumannii , Lipopolissacarídeos , Carboidratos , Dissacarídeos/química , Humanos , Lipopolissacarídeos/química , Oligossacarídeos/química , Polissacarídeos
12.
Clin Transplant ; 35(3): e14198, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33345373

RESUMO

BACKGROUND: We provide detailed analysis and outcomes in patients post-kidney transplant (KT) developing ascites, which has never been categorically reported. METHODS: Ascites was identified by ICD9/10 codes and detailed chart review in patients post-KT from 01/2004-06/2019. The incidence of patient death and graft loss were determined per 100-person-years, and the incidence rate ratio was obtained. RESULTS: Of 3329 patients receiving KT, 83 (2.5%) patients had new-onset ascites, of whom 58% were male, 21% blacks, and 29% whites. Seventy-five percentage were on hemodialysis. Patients were maintained primarily on tacrolimus and mycophenolate for immunosuppression. Only 14% of patients with ascites had the appropriate diagnostic workup. There was a trend toward an increased mortality in patients with ascites (incidence rate ratio, IRR [95% CI]: 1.8 [0.92, 3.19], p = .06), and a significantly higher incidence of graft loss (IRR: 5.62 [3.97, 7.76], p < .001), compared with non-ascites patients. When classified by ascites severity, determined by imaging, moderate/severe ascites patients had the worst clinical outcomes, with a mortality of 32% and graft failure in 57%, compared with 9% and 10%, respectively, in those without ascites. CONCLUSION: In this large cohort employing stepwise analysis of ascites post-KT, worse outcomes were noted, dictating the need for optimized management to improve clinical outcomes.


Assuntos
Transplante de Rim , Ascite/epidemiologia , Ascite/etiologia , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Imunossupressores , Transplante de Rim/efeitos adversos , Masculino , Tacrolimo
13.
Nanotechnology ; 32(44)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34311456

RESUMO

Molybdenum disulfide (MoS2) nanosheets are promising candidates as earth-abundant and low-cost catalyst for hydrogen evolution reaction (HER). Nevertheless, compared with the benchmark Pt/C catalyst, the application of MoS2nanosheets is limited to its relatively low catalytic activity, especially in alkaline environments. Here, we developed a dual-cation doping strategy to improve the alkaline HER performance of MoS2nanosheets. The designed Ni, Co co-doped MoS2nanosheets can promote the tandem HER steps simultaneously, thus leading to a much enhanced catalytic activity in alkaline solution. Density functional theory calculations revealed the individual roles of Ni and Co dopants in the catalytic process. The doped Ni is uncovered to be the active site for the initial water-cleaving step, while the Co dopant is conducive to the H desorbing by regulating the electronic structure of neighboring edge-S in MoS2. The synergistic effect resulted by the dual-cation doping thus facilitates the tandem HER steps, providing an effective route to raise the catalytic performance of MoS2materials in alkaline solution.

14.
Environ Sci Technol ; 55(3): 1885-1896, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33445878

RESUMO

Nanoplastics with small particle sizes and high surface area/volume ratios easily absorb environmental pollutants and affect their bioavailability. In this study, polystyrene nanoplastic beads (PS-NPBs) with a particle size of 100 nm and butyl methoxydibenzoylmethane (BMDBM) sunscreen in personal-care products were chosen as target pollutants to study their developmental toxicity and interactive effects on zebrafish embryos. The exposure period was set from 2 to 12 h postfertilization (hpf). BMDBM and PS-NPBs significantly upregulated genes related to antioxidant enzymes and downregulated the gene expression of aromatase and DNA methyltransferases, but the influenced genes were not exactly the same. The combined exposure reduced the adverse effects on the expression of all genes. With the help of the single-cell RNA sequencing technology, neural mid cells were identified as the target cells of both pollutants, and brain development, head development, and the notch signaling pathway were the functions they commonly altered. The key genes and functions that are specifically affected by BMDBM and/or PS-NPBs were identified. BMDBM mainly affects the differentiation and fate of neurons in the central nervous system through the regulation of her5, her6, her11, lfng, pax2a, and fgfr4. The PS-NPBs regulate the expression of olig2, foxg1a, fzd8b, six3a, rx1, lhx2b, nkx2.1a, and sfrp5 to alter nervous system development, retinal development, and stem cell differentiation. The phenotypic responses of zebrafish larvae at 120 hpf were tested, and significant inhibition of locomotor activity was found, indicating that early effects on the central nervous system would have a sustained impact on the behavior of zebrafish.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Embrião não Mamífero , Larva , Microplásticos , Poliestirenos , Análise de Sequência de RNA , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
15.
Opt Lett ; 45(18): 4996-4999, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32932436

RESUMO

In this Letter, we proposed a super sensitive optic-fiber curvature sensor with ultra-low temperature crosstalk based on Vernier effect and achieved it experimentally. This sensor composes a pair of parallelized 2CFMIs (2-core-fiber Michelson interferometers) in similar lengths, both of which are involved sensing, but there is a rotation angle between their cross-sections. When the rotation angle approaches 180°, the magnification factor for curvature sensitivity is doubled compared with conventional Vernier effect, while for temperature it is always 1. Therefore, advanced curvature sensitivity and abated temperature crosstalk can be realized simultaneously when demodulating Vernier envelops. The experiment results indicate that the curvature sensitivity of this sensor reached 214.533nm/m-1, and temperature crosstalk was as low as 0.000276m-1/∘C. The fabrication process is extremely flexible and repeatable, and the magnification factor of Vernier effect could be controlled conveniently.

16.
Inorg Chem ; 59(1): 930-936, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31840497

RESUMO

The design and construction of highly efficient and stable Pt-free catalysts for the electrocatalytic hydrogen evolution reaction (HER) in alkaline media is extremely desirable. Herein, a novel hybrid of ruthenium (Ru) nanoparticles anchored on graphene hollow nanospheres (GHSs) is synthesized by a template-assisted strategy. The combination of ultrafine Ru nanoparticles and hollow spherical support endows the resultant Ru/GHSs an extraordinary catalytic performance with a low overpotential of 24.4 mV at a current density of 10 mA cm-2, a small Tafel slope of 34.8 mV dec-1, as well as long-term stability in 1.0 M KOH solution, which is, to our knowledge, superior to commercial 20% Pt-C catalyst and most of the state-of-the-art HER electrocatalysts reported. Remarkably, this work provides a new route for the development of other metal-based HER electrocatalysts for energy-related applications.

17.
Transpl Infect Dis ; 22(5): e13347, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32495980

RESUMO

Kaposi sarcoma (KS) is a vascular neoplasm caused by human herpesvirus-8 (HHV-8) infection. KS is most often seen in individuals with acquired immunodeficiency syndrome but can occur in patients who are on immunosuppressive therapy. While the skin and oral mucosa are the typical sites for KS, lesions of the tonsil are quite rare with only a few reported cases. Here, we present a case of tonsillar KS occurring in a renal transplant patient. He presented with dysphagia, odynophagia, and weight loss. Oral examination revealed tonsillar hypertrophy with purple discoloration. Imaging revealed diffuse enlargement of Waldeyer's ring with enlarged right cervical lymph nodes, worrisome for post-transplant lymphoproliferative disorder. Microscopic examination of the tonsillectomy specimen showed a vascular proliferation positive for HHV-8, consistent with KS. The patient was subsequently treated with immunosuppression reduction and the addition of sirolimus, which resulted in complete resolution of oropharyngeal and cervical lesions.


Assuntos
Transplante de Rim , Sarcoma de Kaposi , Herpesvirus Humano 8 , Humanos , Terapia de Imunossupressão , Masculino , Tonsila Palatina
18.
Clin Exp Pharmacol Physiol ; 47(5): 771-779, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31925815

RESUMO

Gallic acid (GA) has a protective effect on the cardiovascular system. To study its cardiac electrophysiological effects, voltage-gated Na+ channel currents (INa ) were recorded in rat cardiomyocytes using whole-cell patch clamp techniques. Moreover, the effects of GA on aconitine-induced arrhythmias were assessed using electrocardiograms in vivo. We found that the current-voltage characteristic curve (I-V curve) of INa significantly shifted in the presence of 1, 3, and 10 µmol/L of GA. The peak sodium current density (INa -Peak) was reduced from -84.02 ± 5.68 pA/pF to -65.78 ± 3.96 pA/pF with 1 µmol/L, -54.45 ± 5.18 pA/pF with 3 µmol/L, and -44.20 ± 4.35 pA/pF with 10 µmol/L, respectively. GA shifted the steady-state activation curve of INa and recovery curve to the right and the steady-state inactivation curve to the left. The observed inhibitory effect was comparable to that of amiodarone. GA pre-treatment significantly prolonged the onset of fatal ventricular fibrillation. Our results indicated that GA inhibited INa in rat ventricular myocytes and aconitine-induced arrhythmias in vivo. These results suggest the potential of GA for development as a novel anti-arrhythmic therapeutic.


Assuntos
Antiarrítmicos/farmacologia , Ácido Gálico/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Fibrilação Ventricular/prevenção & controle , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia , Canais de Sódio Disparados por Voltagem/efeitos dos fármacos , Aconitina , Potenciais de Ação/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Eletrocardiografia , Feminino , Masculino , Miócitos Cardíacos/metabolismo , Ratos Sprague-Dawley , Fatores de Tempo , Fibrilação Ventricular/induzido quimicamente , Fibrilação Ventricular/metabolismo , Fibrilação Ventricular/fisiopatologia , Canais de Sódio Disparados por Voltagem/metabolismo
20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(4): 480-487, 2020 Jul.
Artigo em Zh | MEDLINE | ID: mdl-32691554

RESUMO

OBJECTIVE: To investigate the effects and the mechanism of geniposide on the neuroinflammation occured in the neurodegeneration course of a chronic cerebral hypoperfusion rat model. METHODS: Permanent bilateral common carotid arteries occlusions was performed to induce gradient cognitive deficit in rats. The sham group was used as control group. Then 18 rats that met the Screening Criteria were randomly selected 8 weeks post surgery, and were randomly divided into three groups, the 2-VO rats with saline solution group (2-VO+saline group), 2-VO rats with 50 mg/kg per day geniposide group (2-VO+G50) and 2-VO rats with 100 mg/kg per day geniposide group (2-VO+G100). All intervention groups were daily administered with geniposide or saline for 4 weeks. The sham-operated rats were administrated with saline. Then the rats were tested for Morris water maze to evaluate the memory and learning ability. Rats were sacrificed to obtain cortex and hippocampus tissues for HE staining and to detect expression level of glial fibrillary acidic protein (GFAP), inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-κB), and the level of inflammatory factors tumor necrosis factor-α (TNF-α) and interleukin (IL)-6. RESULTS: The 2-VO+saline group rats showed significant longer escape latency and less percent time in target quadrant, compared with sham-operation group ( P<0.05). The escape latency of 2-VO+G50 and 2-VO+G100 groups were shorter than the 2-VO+saline group ( P<0.05), but still longer than the sham group ( P<0.05), the percent time in target quadrant of which were more than the 2-VO+saline group and less than the sham group. However, there was no significant difference between these two groups. HE staining of sham group showed that neurons in the cortex and hippocampus lined up in order, cellar nucleus were big and globular. HE staining results showed that there were obviously neuoral cells loss, severe cytomorphosis, structural disappearance and nuclear fragmentation in the 2-VO+saline group. The 2-VO+G50 and 2-VO+G100 groups showed less neurodamage than the 2-VO+saline group with less neuoral cells loss, cytomorphosis and ambiguous nucleus. GFAP, iNOS, NF-κB were all highly expressed in the process of cognitive dysfunction in rats after chronic cerebral ischemia, however geniposide intervention (50 and 100 mg/kg per day) significantly decreased the expression of the above proteins. In addition, much more TNF-α and IL-6 were released in brain induced by chronic cerebral ischemia, and the levels were decreased after chronic geniposide oral treatment. No significant differences were detected between 2-VO+G50 and 2-VO+G100 groups. CONCLUSION: These findings demonstrated that geniposide significantly prevented cognition deterioration induced by chronic cerebral hypoperfusion in rats. Geniposide inhibited neuroinflammation occurred in the process of chronic cerebral ischemia probably via reducing iNOS and NF-κB expression and suppressing the release of inflammatory factor TNF-α and IL-6.


Assuntos
Isquemia Encefálica , Transtornos Cognitivos , Hipocampo , Iridoides , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Iridoides/farmacologia , Iridoides/uso terapêutico , Aprendizagem em Labirinto/efeitos dos fármacos , Distribuição Aleatória , Ratos
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