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1.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-982729

RESUMO

Objective:To analyze the site of vestibular nerve damaged in patients with acute vestibular neuritis. Methods:Fifty-seven patients with acute vestibular neuritis were recruited, and each patient underwent caloric irrigation test, video head impulse test(vHIT) and vestibular evoked myogenic potentials(VEMPs). The results were further analyzed. Results:Analysis of abnormal rates of different vestibular function tests: the abnormal rate of caloric irrigation test, horizontal semicircular canal vHIT, anterior semicircular canal vHIT, and posterior semicircular canal vHIT were 92.98%, 92.98%, 92.98%, and 52.63%, respectively. The abnormal rate of cervical vestibular evoked myogenic potentials(cVEMP) and ocular vestibular evoked myogenic potentials(oVEMP) were 52.63% and 89.47%. The abnormal rate of caloric irrigation test, horizontal semicircular canal vHIT, anterior semicircular canal vHIT, and oVEMP were significantly higher than posterior semicircular canal vHIT and cVEMP(P<0.01). Combination analysis of different vestibular function tests: there are twenty-six patients(45.61%, superior and inferior vestibular nerve) with abnormal caloric irrigation test, video head impulse test, and VEMPs. There are twenty-five patients(43.86%, superior vestibular nerve) with abnormal caloric irrigation test, horizontal semicircular canal vHIT, anterior semicircular canal vHIT, and oVEMP. There are 4 patients(7.02%, inferior vestibular nerve) with abnormal posterior semicircular canal vHIT and cVEMP. There are two patients(3.51%, ampullary vestibular nerve) with abnormal caloric irrigation test, horizontal semicircular canal vHIT, and anterior semicircular canal vHIT. The rate of superior and inferior vestibular neuritis and superior vestibular neuritis were significantly higher than inferior vestibular neuritis and ampullary vestibular neuritis(P<0.01). Conclusion:Acute vestibular neuritis subtypes can be divided into four categories: superior and inferior vestibular neuritis, superior vestibular neuritis, inferior vestibular neuritis, and ampullary vestibular neuritis. Video head impulse test can accurately assess the site of vestibular nerve damage in patients with acute vestibular neuritis. In addition, vHIT combined with VEMPs can provide objective evidence for the diagnosis of ampullary vestibular neuritis.


Assuntos
Humanos , Neuronite Vestibular/diagnóstico , Vestíbulo do Labirinto , Nervo Vestibular , Canais Semicirculares , Teste do Impulso da Cabeça/métodos
2.
Front Cell Infect Microbiol ; 12: 877205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034706

RESUMO

Objectives: There are few studies of metagenomic next-generation sequencing (mNGS) in immunocompromised patients assisted by veno-venous extracorporeal membrane oxygenation (vv-ECMO). The present study is aimed to investigate the pathogen-detected effect and clinical therapy value of mNGS technologies in immunocompromised patients assisted by vv-ECMO. Methods: Our study retrospectively enrolled 46 immunocompromised patients supported by vv-ECMO from Jan 2017 to June 2021 at the First Affiliated Hospital of Zhengzhou University, respectively. Patients were divided into the deterioration group (Group D) (n = 31) and improvement group (Group I) (n = 15) according to their outcomes. Baseline characteristics and etiological data of patients during hospitalization of 2 groups were compared. The pathogens detected by mNGS and antibiotic regimens guided by mNGS in immunocompromised patients assisted by vv-ECMO were analyzed. Results: Compared with Group I, the deterioration patients showed a higher percentage of chronic obstructive pulmonary disease (COPD) (32.3% vs. 6.7%, p < 0.01) and were significantly older (47.77 ± 16.72 years vs. 32 ± 15.05 years, p < 0.01). Within 48 h of being ECMO assisted, the consistency of the samples detected by traditional culture and mNGS at the same time was good (traditional culture vs. mNGS detection, the positive rate of bronchoalveolar lavage fluid (BALF) culture: 26.1% vs. 30.4%; the positive rate of blood sample culture: 12.2% vs. 12.2%, p > 0.05). However, mNGS detected far more pathogen species and strains than conventional culture (30 strains vs. 78 strains, p < 0.01); the most popular pathogen was Klebsiella pneumoniae. Parts of patients had their antibiotic treatment adjustments, and the improvement patients showed less usage of broad-spectrum antibiotics. Conclusions: mNGS may play a relatively important role in detecting mixed pathogens and personalized antibiotic treatment in immunocompromised patients assisted by vv-ECMO.


Assuntos
Oxigenação por Membrana Extracorpórea , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Antibacterianos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hospedeiro Imunocomprometido , Metagenômica , Estudos Retrospectivos
3.
Thromb J ; 20(1): 36, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761333

RESUMO

BACKGROUND: The anti-coagulation protocol of patients with hemorrhage risk primary disease who need extracorporeal membrane oxygenation (ECMO) supported is controversial. This study evaluated the feasibility of a new anti-coagulation strategy, that is heparin-free after 3000 IU heparin loaded in veno-venous ECMO (VV ECMO) supported acute respiratory failure patients with hemorrhage risk. METHODS: A retrospective study was performed in a series of hemorrhage risk patients supported with VV ECMO at the First Affiliated Hospital of Zhengzhou University, between June 2012 to Sept 2020. A total of 70 patients received a low heparin bolus of 3000 units for cannulation but without subsequent, ongoing heparin administration. Patients were divided into survival (n = 25) and non-survival group (n = 45). Data of coagulation, hemolysis and membrane lung function were calculated and analyzed. The complications of patients were recorded. Finally, the binary Logistic regression was conducted. RESULTS: The longest heparin-free time was 216 h, and the mean heparin-free time was 102 h. Compared with survivors, the non-survivors were showed higher baseline SOFA score and lower platelet counts in 0.5 h, 24 h, 48 h and 96 h after ECMO applied. However, there was no significant differences between survivors and non-survivors in ACT, APTT, INR, D-dimer, fibrinogen, LDH, blood flow rate, Δp and Ppost-MLO2 (all p < 0.05) of all different time point. Moreover, only the baseline SOFA score was significantly associated with mortality (p < 0.001, OR(95%CI): 2.754 (1.486-5.103)) while the baseline levels of ACT, APTT, INR, platelet, D-dimer, fibrinogen and LDH have no association with mortality. The percentage of thrombosis complications was 54.3% (38/70) including 3 oxygenator changed but there was no significant difference of complications in survival and non-survival groups (p > 0.05). CONCLUSIONS: The anticoagulation protocol that no heparin after a 3000 units heparin bolus in VV ECMO supported acute respiratory failure patients with hemorrhage risk is feasible.

4.
Chinese Journal of Neurology ; (12): 738-742, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-957962

RESUMO

Leukoencephalopathy with vanishing white matter (VWM) is one of the most prevalent inherited childhood white-matter disorders, and the pathogenic gene has been confirmed as EIF2B gene. VWM is characterized by chronic progressive neurological deterioration with cerebellar ataxia, usually less prominent spasticity and relatively mild mental decline. There are episodes of rapid and major neurological deterioration provoked by stresses, such as fever, minor physical trauma and acute fright, which is a characteristic clinical feature of VWM. Brain magnetic resonance imaging findings are diagnostic in almost all patients,and the disappearance of the cerebral white matter occurs in a diffuse "melting away" pattern. The onset of VWM can be at any age from fetal stage to adult stage, and the clinical phenotypes vary immensely. Gene diagnosis is the golden standard for VWM. This article reported a patient with a course of 17 years, who was misdiagnosed as Wilson′s disease because of low serum ceruloplasmin, and was finally diagnosed as VWM by reinterpretation of whole exome sequencing, which is worthy of clinicians′ vigilance and consideration.

5.
International Eye Science ; (12): 2092-2095, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-829712

RESUMO

@#Chronic dacryocystitis(CD)is a disease caused by microorganism infection secondary to nasolacrimal duct stenosis or obstruction. Its pathological changes are of great significance to the diagnosis, treatment and prognosis of patients. This paper summarizes the characteristics of the pathological changes of the lacrimal drainage system and surrounding tissues by reading a large number of domestic and foreign literatures on chronic dacryocystitis in recent years, aiming at improving clinicians' understanding, doing better diagnosis, treatment and prognosis judgment, and providing ideas for further research.

6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-843137

RESUMO

Eosinophilic gastroenteritis (EGE) is a rare chronic disease of digestive system, characterized by the eosinophil infiltration of the gastrointestinal tract and the thickening of the gastrointestinal wall. At present, the etiology and pathogenesis of EGE are still unclear. Accompanied with eosinophilia and elevation of serum immunoglobulin E, the clinical manifestations of EGE are dependent on the location of lesions and the extent or depth of eosinophil infiltration in the gastrointestinal tract. The thickening or edema of the gastrointestinal wall, nodular-like changes, intestinal stenosis and ascites can be regarded as common radiological findings of EGE, while erythema, hyperemia or edema, erosion and ulcer of mucosal are the endoscopic features of EGE. Tissue biopsy is helpful for the diagnosis of EGE. However, with unspecific clinical manifestations, laboratory tests, radiological and endoscopic findings and unidentified cut-off count of pathological diagnostic criteria, EGE is very difficult to be diagnosed. Therefore, this paper mainly reviews the research progress in the diagnosis and treatment of EGE, attempting to improve the clinicians' understanding of EGE.

7.
Acta Pharmaceutica Sinica ; (12): 2665-2673, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-837526

RESUMO

In this study, the effect of benzo[α]pyrene (BaP) on chaperone-mediated autophagy (CMA) in a simulated hypoxia environment was observed and the relationship to heat shock protein 90 (HSP90) was clarified. With HSP90 inhibitor geldanamycin (GA) and HSP90α silenced, the mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α), HSP90, heat shock cognate protein 70 (HSC70), and lysosomal associated protein 2A (LAMP-2A) of A549 cells on hypoxic environment by BaP were tested. Alkaline comet experiment, immunofluorescence γ-H2AX focus experiment, quantitative real-time PCR (qPCR), and Western blot analyses were used to clarify the relationship between the DNA damage of different concentrations of BaP in A549 cells and the mRNA and protein expression of CMA-related factors. The results show that hypoxia can promote the expression of mRNA and protein of CMA-related factors in A549 cells. This study found that BaP has an inhibitory effect on CMA under the hypoxic environment. The inhibition or silencing of HSP90 will enhance the inhibitory effect of BaP on CMA. In a normoxic environment, BaP causes DNA damage and promotes CMA.

8.
Arch Virol ; 164(5): 1335-1341, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30848390

RESUMO

In infants, hepatitis B virus (HBV) infections are mainly acquired by mother-to-child transmission (MTCT). Current tests for the presence of HBV markers at birth can neither confirm nor exclude MTCT. The aim of this study was to find an early diagnostic marker of HBV MTCT. From 2011 to 2016, we studied a total of 5999 pregnant women who gave birth at our hospital in Shenzhen City, China. HBsAg-positive mothers and their offspring (n=386 pairs) were tested at birth for HBV markers, and 207 infants were followed up at 7-12 months after birth. The HBsAg-seropositive rate of the pregnant women was 12.5%. Additionally, 28.0%, 36.0%, 98.5% and 6.6% of umbilical cord (UC) blood samples of neonates were found to be positive for HBsAg, HBeAg, anti-HBc and HBV-DNA, respectively, whereas for neonatal femoral venous (FV) blood, the percentages were 16.2%, 38.0%, 98.8% and 2.6%, respectively. Mothers with high HBV DNA loads and those who were HBeAg positive were the most likely to have HBV-positive offspring. Immunoprophylaxis failed in five infants: the difference in median HBV DNA titer between UC blood from infants with and without HBV MTCT was statistically significant, and there was no significant difference in HBV DNA titer between UC blood and in peripheral blood of infants with HBV MTCT. In conclusion, we found that HBeAg positivity and high HBV loads are strong risk factors for MTCT of HBV and that the HBV DNA titer in the UC is a good predictor for HBV MTCT.


Assuntos
Anticorpos Antivirais/sangue , Anticorpos Anti-Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/isolamento & purificação , Hepatite B/diagnóstico , Biomarcadores , DNA Viral/sangue , Diagnóstico Precoce , Feminino , Hepatite B/epidemiologia , Hepatite B/transmissão , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Gravidez , Complicações Infecciosas na Gravidez , Carga Viral
9.
Chinese Journal of Neurology ; (12): 150-152, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-734908

RESUMO

To standardize diagnosis and treatment of vertigo,Chinese Society of Neurology and Editorial Board of Chinese Journal of Neurology organized vertigo experts to update 2010 expert consensus on diagnosis and treatment of vertigo.New version of multidisciplinary expert consensus on diagnosis and treatment of vertigo was published in November 2017 (hereinafter referred to as consensus).However,due to limitation on space,many details in consensus were not illustrated.Hence,the relevant contents will be stated in this article.

10.
Oxid Med Cell Longev ; 2018: 6069150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30581534

RESUMO

The aim of this study was to investigate whether uric acid (UA) might exert neuroprotection via activating the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway and regulating neurotrophic factors in the cerebral cortices after transient focal cerebral ischemia/reperfusion (FCI/R) in rats. UA was intravenously injected through the tail vein (16 mg/kg) 30 min after the onset of reperfusion in rats subjected to middle cerebral artery occlusion for 2 h. Neurological deficit score was performed to analyze neurological function at 24 h after reperfusion. Terminal deoxynucleotidyl transferase-mediated dNTP nick end labeling (TUNEL) staining and hematoxylin and eosin (HE) staining were used to detect histological injury of the cerebral cortex. Malondialdehyde (MDA), the carbonyl groups, and 8-hydroxyl-2'-deoxyguanosine (8-OHdG) levels were employed to evaluate oxidative stress. Nrf2 and its downstream antioxidant protein, heme oxygenase- (HO-) 1,were detected by western blot. Nrf2 DNA-binding activity was observed using an ELISA-based measurement. Expressions of BDNF and NGF were analyzed by immunohistochemistry. Our results showed that UA treatment significantly suppressed FCI/R-induced oxidative stress, accompanied by attenuating neuronal damage, which subsequently decreased the infarct volume and neurological deficit. Further, the treatment of UA activated Nrf2 signaling pathway and upregulated BDNF and NGF expression levels. Interestingly, the aforementioned effects of UA were markedly inhibited by administration of brusatol, an inhibitor of Nrf2. Taken together, the antioxidant and neuroprotective effects afforded by UA treatment involved the modulation of Nrf2-mediated oxidative stress and regulation of BDNF and NGF expression levels. Thus, UA treatment could be of interest to prevent FCI/R injury.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Ácido Úrico/uso terapêutico , 8-Hidroxi-2'-Desoxiguanosina , Animais , Western Blotting , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Ensaio de Imunoadsorção Enzimática , Heme Oxigenase-1/metabolismo , Imunoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
11.
Cell Stress Chaperones ; 22(1): 55-65, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27812888

RESUMO

Recent studies have shown 5-hydroxymethyl-2-furfural (5-HMF) has favorable biological effects, and its neuroprotection in a variety of neurological diseases has been noted. Our previous study showed that treatment of 5-HMF led to protection against permanent global cerebral ischemia. However, the underlying mechanisms in cerebral ischemic injury are not fully understood. This study was conducted to investigate the neuroprotective effect of 5-HMF and elucidate the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway mechanism in the striatum after transient global cerebral ischemia. C57BL/6 mice were subjected to bilateral common carotid artery occlusion for 20 min and sacrificed 24 h after reperfusion. 5-HMF (12 mg/kg) or an equal volume of vehicle was intraperitoneally injected 30 min before ischemia and 5 min after the onset of reperfusion. At 24 h after reperfusion, neurological function was evaluated by neurological disability status scale, locomotor activity test and inclined beam walking test. Histological injury of the striatum was observed by cresyl violet staining and terminal deoxynucleotidyl transferase (TdT)-mediated dNTP nick end labeling (TUNEL) staining. Oxidative stress was evaluated by the carbonyl groups introduced into proteins, and malondialdehyde (MDA) levels. An enzyme-linked immunosorbent assay (ELISA)-based measurement was used to detect Nrf2 DNA binding activity. Nrf2 and its downstream ARE pathway protein expression such as heme oxygenase-1, NAD (P)H:quinone oxidoreductase 1, glutamate-cysteine ligase catalytic subunit and glutamate-cysteine ligase modulatory subunit were detected by western blot. Our results showed that 5-HMF treatment significantly ameliorated neurological deficits, reduced brain water content, attenuated striatum neuronal damage, decreased the carbonyl groups and MDA levels, and activated Nrf2/ARE signaling pathway. Taken together, these results demonstrated that 5-HMF exerted significant antioxidant and neuroprotective effects following transient cerebral ischemia, possibly through the activation of the Nrf2/ARE signaling pathway.


Assuntos
Furaldeído/análogos & derivados , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Elementos de Resposta Antioxidante/fisiologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Furaldeído/farmacologia , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-307139

RESUMO

To screen the anti-inflammatory active fraction of unripe Forsythiae Fructus, and elucidate the action mechanism, water decoction, ethyl acetate portion, n-butanol portion and residue water extracts of unripe Forsythiae Fructus were administered into rats for continuously 15 days. The acute lung injury inflammatory model was established to observe the section structure of lung tissues. Levels of IL-6, TNF-α, IL-1β and IL-10 in bronchoalveolar lavage fluid were determined by ELISA kits, and changes in endogenous metabolites in serum were analyzed based on 1H-NMR metabolomics. The results showed that ethyl acetate portion of unripe Forsythiae Fructus had a better anti-inflammatory activity against acute lung injury, and could suppress the release of inflammatory factors of IL-6, TNF-α, IL-1β, significantly reduce contents of creatine, β-OH-butyrate, succinate, lysine, valine, isoleucine and glutamine, and elevate the content of GPC in serum. Ethyl acetate portion was proved to be the main fraction of anti-inflammatory activity from the perspective of endogenous metabolites in serum, and played an anti-inflammatory role by regulating creatine metabolism, choline metabolism, branched-chain amino acid metabolism and TCA cycles. This study could lay a foundation for studying pharmacodynamic material basis of unripe Forsythiae Fructus.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-853566

RESUMO

As a representative of controlled release preparations, osmotic pump has become a hot spot in the new preparation researches of Chinese materia medica (CMM). This paper reviewed CMM osmotic pump preparation from the following aspects: structure type of osmotic pump preparation, adjuncts of osmotic pump preparation of CMM, in vivo evaluation, and problems existing currently, which aimed to provide ideas and methods for the development of CMM osmotic pump preparation.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(10): 2697-702, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26904802

RESUMO

We specify water vapor among combustion products as the target gas based on tunable diode absorption spectroscopy in this paper. The direct absorption signals of water vapor after being processed can be used to calculate the gas concentration distributions and temperature distributions of the combustion region of methane and air flat flame furnace via algebraic reconstruction technique (ART). In the numerical simulation, reconstruction region is a grid of five by five, we assume a temperature and water vapor concentration distribution of 25 grid, then simulate different direction laser rays which cross the combustion region, generating projection of each ray, by ART reconstruction algorithm, it turns out that the temperature and water vapor distribution reconstruction error is less than 1%. In the experiment, we chose a distributed-feedback laser to scan the target gas H2O7 153.722, 7 153.748 and 7 154.354 cm(-1) as absorbtion line pair to measure temperature of the flame, we consider the former two line as one absorbtion line. By Stages multi-directional scanning, the authors abtain 16 different regions distributin of temperature and gas concentration of furnace when we collecte 30 different angle data by spectral data processing, reconstruction algorithm, two absorbtion line ratio method for temperature sensing, finding the temperature and water concentration are higher in the center than in the edge, it turns out that the reconstruction algorithm is good enough to achieve the distributions of gas concentration and temperature of the combustion region.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-337947

RESUMO

Amounts of researches show that EPO is characterized with neurotrophic and neuroprotective manner, especially in brain stroke, which attracts a large numbers of researchers to study it. With the accumulating researches on its neuroprotection, many related mechanisms were revealed, such as antioxidant, anti-apoptosis, angiogenesis, anti-inflammatory, which suggests a multiple targets role of EPO on brain stroke. However, because of the high risk of thromboembolism in clinical administration of rhEPO and its analogs, the herbs are potential to be a replacer for its less side effects. Many researchers suggested that a larger of herbs were founded having the action of increasing the endogenous EPO in the model of anemia and cerebral ischemia. At the same time, there herbs were also proved that they had the action of against cerebral ischemia while some without considering the role of EPO in the reports. Considering of the action of promoting EPO of these herbs and the neural protection of EPO, this essay mainly summarizes the studies of herbs promoting EPO in the cerebral ischemia and discusses the mechanism of regulating the EPO of these herbs, for the aim of finding the potential drugs against cerebral ischemia.


Assuntos
Animais , Humanos , Isquemia Encefálica , Tratamento Farmacológico , Genética , Metabolismo , Medicamentos de Ervas Chinesas , Farmacologia , Eritropoetina , Genética , Metabolismo , Neuroproteção , Plantas Medicinais , Química
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(12): 3174-7, 2014 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25881402

RESUMO

Tunable diode laser absorption spectroscopy (TDLAS) has been developed to realize the real-time and dynamic measurement of the combustion temperature, gas component concentration, velocity and other flow parameters, owing to its high sensitivity, fast time response, non-invasive character and robust nature. In order to obtain accurate water vapor concentration at high temperature, several absorption spectra of water vapor near 1.39 µm from 773 to 1273 K under ordinary pressure were recorded in a high temperature experiment setup using a narrow band diode laser. The absorbance of high temperature absorption spectra was calculated by combined multi-line nonlinear least squares fitting method. Two water vapor absorption lines near 7154.35 and 7157.73 cm(-1) were selected for measurement of water vapor at high temperature. A model method for high temperature water vapor concentration was first proposed. Water vapor concentration from the model method at high temperature is in accordance with theoretical reasoning, concentration measurement standard error is less than 0.2%, and the relative error is less than 6%. The feasibility of this measuring method is verified by experiment.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(4): 881-5, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23841390

RESUMO

Tunable diode laser absorption spectroscopy (TDLAS) is a new gas detection technique developed recently with high spectral resolution, high sensitivity and fast time response. The second-harmonic signal of wavelength modulation spectroscopy (WMS) is often used as the detection signal for gas concentration inversion. Using Simulink, a visual modeling and simulation platform, the authors simulated the WMS signal based on TDLAS, and got the second-harmonic signal by using lock-in amplifier algorithm. Digital orthogonal algorithm was studied in this paper. The relationship between second-harmonic signals and the modulation indexes was analyzed by comparing changes of second-harmonic under different modulation indexes, in order to find out the optimized parameters for second-harmonic detection.

18.
Neurol Sci ; 34(8): 1355-65, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23187788

RESUMO

Cholesterol plays an important role in synaptic plasticity, learning and memory. To better explore how dietary cholesterol contributes to learning and memory and the related changes in synaptic structural plasticity, rats were categorized into a regular diet (RD) group and a cholesterol-enriched diet (CD) group, and were fed with respective diet for 2 months. Dietary cholesterol impacts on learning and memory, hippocampal synaptic ultrastructure, expression levels of postsynaptic density-95 (PSD-95), synaptophysin (SYP) and cannabinoid receptor type 1 (CB1R) were investigated. We found CD rats had better performances in learning and memory using Morris water maze and object recognition test than RD rats. The memory improvement was accompanied with alterations of synaptic ultrastructure in the CA1 area of the hippocampus evaluated by electron microscopy, enhanced immunoreactivity of SYP, a presynaptic marker in hippocampus detected by immunocytochemistry, as well as increased levels of PSD-95, SYP and decreased level of CB1R in brains of CD rats determined by Western blot. Taken together, the results suggest that the improvement of learning and memory abilities of the young adult rats induced by dietary cholesterol may be linked with changes in synaptic structural plasticity in the brain.


Assuntos
Colesterol na Dieta/farmacologia , Hipocampo/efeitos dos fármacos , Memória/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Animais , Colesterol na Dieta/análise , Colesterol na Dieta/sangue , Hipocampo/ultraestrutura , Masculino , Ratos , Ratos Wistar , Sinapses/ultraestrutura
19.
Neurochem Res ; 35(5): 773-81, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20155318

RESUMO

The capacity of cornel iridoid glycoside (CIG) to suppress the manifestations of ischemic stroke was investigated. CIG was administered to rats by the intragastric route once daily for 7 days. Focal cerebral ischemia was induced by 2 h of middle cerebral artery occlusion followed by 24 h of reperfusion. In non-treated rats large infarct areas were observed within 24 h of reperfusion. Examination of the ischemic cerebral cortex revealed microglia and astrocyte activation, increased interleukin-1beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) concentrations, increased DNA fragmentation in the ischemia penumbra, elevated Bax expression, increased caspase-3 cleavage, and decreased Bcl-2 expression. Pretreatment with CIG decreased the infarct area, DNA fragmentation, IL-1beta and TNF-alpha concentrations, microglia and astrocyte activation, Bax expression, and caspase-3 cleavage while increasing Bcl-2 expression. CIG exerts anti-neuroinflammatory and anti-apoptotic effects which should prove beneficial for prevention or treatment of stroke.


Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Glicosídeos/farmacologia , Iridoides/farmacologia , Animais , Isquemia Encefálica/patologia , Infarto Cerebral/patologia , Infarto Cerebral/prevenção & controle , Cornus/química , Glicosídeos/uso terapêutico , Infarto da Artéria Cerebral Média/patologia , Inflamação/prevenção & controle , Interleucina-1beta/metabolismo , Iridoides/uso terapêutico , Masculino , Neuroglia/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Fator de Necrose Tumoral alfa/metabolismo
20.
Zhonghua Yi Xue Za Zhi ; 88(1): 31-5, 2008 Jan 01.
Artigo em Chinês | MEDLINE | ID: mdl-18346377

RESUMO

OBJECTIVE: To investigate changes of synapse related protein, such as synaptophysin (SYP) and postsynaptic dense material 95 (PSD-95), in brains of 10 months old transgenic mice, and the effects of Epimedium flavonoids (EF) on expression of SYP and PSD-95 in brain of 10 months old of APP transgenic mice. METHODS: The mice of drug treated group were administered intragastrically by EF (at low doses of 0.03 and high dose of 0.1 g.kg(-1).d(-1)) from 4 to 10 months old. The mice of normal group and negative transgene group were administered of distilled water by the same way. The expression of SYP in CA1, CA3, and dentate gyrus (DG) areas of hippocampus and cortex, and PSD-95 in hippocampus and cortex were detected by immunohistochemistry and Western blot respectively. RESULTS: Compared to negative transgenic mice, the expression of SYP in cortex was decreased by 51.3% (P < 0.01). The IOD value of SYP immuno-reactivity cell in CA1, CA3 and DG areas of hippocampus in 10 months old transgenic mice were significantly decreased (the suppression rates were 59.1%, 57.7% and 56.5% in CA1, CA3 and DG respectively, all P < 0.01). The expression of PSD-95 in cortex decreased by 36.4% (P < 0.01). The count of PSD-95 immuno-reactivity cell in CA1 area of hippocampus decreased with the suppression rate of 18.5% (P < 0.05). After being administered intragastrically by EF for 6 months, the expression of SYP in cortex of EF low doses and high dose group mice increased by 40.0% (P < 0.05) and 106.4% (P < 0.01) respectively in comparison with that of the control group. The IOD value of SYP immuno-reactivity cell in hippocampal CA1, CA3 and DG areas of EF low and high dose group mice were all significantly increased (all P < 0.01). The expression of PSD-95 in cortex of EF low and high dose group mice increased by 57.3% (P < 0.05) and 84.3% (P < 0.01) respectively when compare to the control group. The count of PSD-95 immuno-reactivity cell in CA1 area of hippocampus of mice in EF high dose group increased by 22.5% (P < 0.05). CONCLUSION: Epimedium flavonoids could protect the synaptic structure and function by promoting the expression of synaptophysin and postsynaptic dense material 95, which suggest that Epimedium Flavonoids may have a promising application prospect in improving the synaptic impairment of AD.


Assuntos
Encéfalo/efeitos dos fármacos , Demência/tratamento farmacológico , Epimedium , Flavonas/farmacologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Proteína 4 Homóloga a Disks-Large , Relação Dose-Resposta a Droga , Feminino , Flavonas/uso terapêutico , Guanilato Quinases , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Transgênicos , Sinucleínas/biossíntese
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