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Salmonella enterica serovar Typhimurium, a Gram-negative bacterium, can cause infectious diseases ranging from gastroenteritis to systemic dissemination and infection. However, the molecular mechanisms underlying this bacterial dissemination have yet to be elucidated. A study indicated that using the lipopolysaccharide (LPS) core as a ligand, S Typhimurium was able to bind human dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (hCD209a), an HIV receptor that promotes viral dissemination by hijacking antigen-presenting cells (APCs). In this study, we showed that S Typhimurium interacted with CD209s, leading to the invasion of APCs and potentially the dissemination to regional lymph nodes, spleen, and liver in mice. Shielding of the exposed LPS core through the expression of O-antigen reduces dissemination and infection. Thus, we propose that similar to HIV, S Typhimurium may also utilize APCs via interactions with CD209s as a way to disseminate to the lymph nodes, spleen, and liver to initiate host infection.
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Moléculas de Adesão Celular/fisiologia , Lectinas Tipo C/fisiologia , Receptores de Superfície Celular/fisiologia , Salmonella typhimurium/patogenicidade , Animais , Células Apresentadoras de Antígenos/microbiologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Lipopolissacarídeos/fisiologia , Mananas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Antígenos O/fisiologia , Nódulos Linfáticos Agregados/fisiologia , Fagocitose , Células RAW 264.7RESUMO
Yersinia pseudotuberculosis is a Gram-negative enteropathogen and causes gastrointestinal infections. It disseminates from gut to mesenteric lymph nodes (MLNs), spleen, and liver of infected humans and animals. Although the molecular mechanisms for dissemination and infection are unclear, many Gram-negative enteropathogens presumably invade the small intestine via Peyer's patches to initiate dissemination. In this study, we demonstrate that Y. pseudotuberculosis utilizes its lipopolysaccharide (LPS) core to interact with CD209 receptors, leading to invasion of human dendritic cells (DCs) and murine macrophages. These Y. pseudotuberculosis-CD209 interactions result in bacterial dissemination to MLNs, spleens, and livers of both wild-type and Peyer's patch-deficient mice. The blocking of the Y. pseudotuberculosis-CD209 interactions by expression of O-antigen and with oligosaccharides reduces infectivity. Based on the well-documented studies in which HIV-CD209 interaction leads to viral dissemination, we therefore propose an infection route for Y. pseudotuberculosis where this pathogen, after penetrating the intestinal mucosal membrane, hijacks the Y. pseudotuberculosis-CD209 interaction antigen-presenting cells to reach their target destinations, MLNs, spleens, and livers.
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Moléculas de Adesão Celular/metabolismo , Células Dendríticas/microbiologia , Endocitose , Interações Hospedeiro-Patógeno , Lectinas Tipo C/metabolismo , Lipopolissacarídeos/metabolismo , Macrófagos/microbiologia , Receptores de Superfície Celular/metabolismo , Yersinia pseudotuberculosis/patogenicidade , Animais , Aderência Bacteriana , Células Cultivadas , Modelos Animais de Doenças , Humanos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ligação Proteica , Yersiniose/microbiologia , Yersiniose/patologia , Yersiniose/fisiopatologiaRESUMO
Objective To analyze the risk factors of intrauterine adhesion (IUA) after hysteroscopic resection of endometrial polyps. Methods Totally 359 patients undergoing hysteroscopic resection of endometrial polyps from January 2013 to December 2016 were enrolled in this study. The clinical data of IUA group and non-IUA group were compared. Univariate analysis was performed to identify the risk factors of IUA,and multivariate Logistic regression analysis was further performed to get the independent risk factors. Results Of these 359 patients,IUA occured after operation in 56 patients (15.60%). Univariate analysis showed underlying diseases (χ2=7.381,P=0.004),multiple polyps (χ2=3.376,P=0.040),uterus with uterine fibroids or endometrial hyperplasia (χ2=6.495,P=0.009),history of curettage(χ2=31.576,P=0.000),pelvic infection (χ2=8.582,P=0.001),intrauterine device (χ2=7.161,P=0.006),history of cesarean section (χ2=5.493,P=0.014),and multigravida were (χ2=16.886,P=0.000) the risk factors of IUA. Logistic regression analysis showed other diseases of uterus(χ2=19.542,P=0.026),history of curettage (χ2=29.614,P=0.000),pelvic infection (χ2=5.627,P=0.002),intrauterine device (χ2=11.342,P=0.08),history of cesarean section(χ2=8.549,P=0.035),and multigravida (χ2=15.493,P=0.000) were the independent risk factors of IUA after hysteroscopic resection of endometrial polyps. Conclusion Other diseases of uterus,history of curettage,pelvic infection,intrauterine device,history of cesarean section,and/or multigravida can increase the risk of IUA after hysteroscopic resection of endometrial polyps.
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Doenças Uterinas , Cesárea , Feminino , Humanos , Histeroscopia , Leiomioma , Pólipos , Gravidez , Fatores de Risco , Aderências Teciduais , Neoplasias UterinasRESUMO
Bifunctional chiral squaramide-catalyzed highly enantioselective Michael addition of nitromethane to diverse 2-enoylazaarenes was successfully performed. This protocol provided a set of chiral azaarene-containing γ-nitroketones with up to 98% yield and 98% ee in a solvent-free catalytic system under mild conditions. Furthermore, gram-scale synthetic utility was also showcased.
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Dehydroabietane-type bifunctional organocatalysts derived from rosane-type diterpenes of dehydroabietic acid (DHAA) and dehydroabietylamine (DA) have been utilized in a wide variety of highly enantioselective reactions. Since one well-documented review exclusively reported on the development of terpene-derived bifunctional thioureas in asymmetric organocatalysis in 2013, fragmentary progress on the dehydroabietane-type bifunctional thioureas and squaramides has been mentioned in other reviews. In this mini-review, we systematically analyze and reorganize the published literature on dehydroabietane-type bifunctional organocatalysts in the recent decade according to the type of catalysts. Our aim is for this review to provide helpful research information and serve as a foundation for further design and application of rosin-based organocatalysts.
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The neurons in the mesencephalic trigeminal nucleus (MeV) play essential roles in proprioceptive sensation of the face and oral cavity. The somata of MeV neurons are generally assumed to carry out neuronal functions but not to play a direct role in synaptic transmission. Using whole-cell recording and membrane capacitance (C(m)) measurements, we found that the somata of MeV neurons underwent robust exocytosis (C(m) jumps) upon depolarization and with the normal firing of action potentials in brain slices. Both removing [Ca(2+)](o) and buffering [Ca(2+)](i) with BAPTA blocked this exocytosis, indicating that it was completely Ca(2+) dependent. In addition, an electron microscopic study showed synaptic-like vesicles approximated to the plasma membrane in somata. There was a single Ca(2+)-dependent releasable vesicle pool with a peak release rate of 1912 fF s(-1). Importantly, following depolarization-induced somatic exocytosis, GABA-mediated postsynaptic currents were transiently reduced by 31%, suggesting that the somatic vesicular release had a retrograde effect on afferent GABAergic transmission. These results provide strong evidence that the somata of MeV neurons undergo robust somatic secretion and may play a crucial role in bidirectional communication between somata and their synaptic inputs in the central nervous system.
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Cálcio/fisiologia , Exocitose/fisiologia , Neurônios/fisiologia , Núcleos do Trigêmeo/fisiologia , Potenciais de Ação/fisiologia , Animais , Técnicas In Vitro , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To evaluate the effect of heat shock protein 90 (HSP90) on hepatitis B virus (HBV) replication in hepatocytes and to investigate the related molecular mechanism. METHODS: A eukaryotic plasmid expressing human HSP90 was constructed (designated as HA-HSP90). HepG2 cells were co-transfected with HA-HSP90 and the HBV replicative plasmid HBV1.3. Expression of the exogenous HSP90 was assessed by Western blotting. Expression of the HBV surface antigen (HBsAg) was determined by enzyme-linked immunosorbent assay, and HBV replicative intermediates were detected by Southern blotting. Small interfering (si)RNAs were designed against HSP90 and TBK1 and transfected into the HepG2 cells to further assess the effects of HSP90 and its underlying mechanism. HSP90-mediated effects on the expression of interleukins IL-1b and IL-6 and the interferon response gene IFIT1 were assessed by quantitating mRNA levels with real time RT-PCR. RESULTS: The HA-HSP90 plasmid successfully expressed exogenous HSP90 protein in HepG2 cells. The exogenous HSP90 was able to inhibit HBV replication and HBsAg expression. IFIT1 expression was up-regulated after HA-HSP90 transfection, but neither IL-1b nor IL-6 were affected. The siRNA-mediated TBK1 down-regulation had no effect on the HSP90-inhibited HBV replication. CONCLUSION: HSP90 can inhibit HBV replication and TBK1 is not involved in this process.
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Proteínas de Choque Térmico HSP90/genética , Vírus da Hepatite B/fisiologia , Replicação Viral , Células Hep G2 , Antígenos E da Hepatite B/metabolismo , Humanos , Proteínas Serina-Treonina Quinases/genética , TransfecçãoRESUMO
Patterns of action potentials (APs), often in the form of bursts, are critical for coding and processing information in the brain. However, how AP bursts modulate secretion at synapses remains elusive. Here, using the calyx of Held synapse as a model we compared synaptic release evoked by AP patterns with a different number of bursts while the total number of APs and frequency were fixed. The ratio of total release produced by multiple bursts to that by a single burst was defined as 'burst-effect'.We found that four bursts of 25 stimuli at 100 Hz increased the totalcharge of EPSCs to 1.47 ± 0.04 times that by a single burst of 100 stimuli at the same frequency.Blocking AMPA receptor desensitization and saturation did not alter the burst-effect, indicating that it was mainly determined by presynaptic mechanisms. Simultaneous dual recordings of presynaptic membrane capacitance (Cm) and EPSCs revealed a similar burst-effect, being 1.58±0.13by Cm and 1.49±0.05 by EPSCs. Reducing presynapticCa2+ influx by lowering extracellular Ca2+concentration or buffering residual intracellular Ca2+ with EGTA inhibited the burst-effect. We further developed a computational model largely recapitulating the burst-effect and demonstrated that this effect is highly sensitive to dynamic change in availability of the releasable pool of synaptic vesicles during various patterns of activities. Taken together, we conclude that AP bursts modulate synaptic output mainly through intricate interaction between depletion and replenishment of the large releasable pool. This burst-effect differs from the somatic burst-effect previously described from adrenal chromaffin cells, which substantially depends on activity-induced accumulation of Ca2+ to facilitate release of a limited number of vesicles in the releasable pool. Hence, AP bursts may play an important role in dynamically regulating synaptic strength and fidelity during intense neuronal activity at central synapses.
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Potenciais de Ação , Tronco Encefálico/metabolismo , Potenciais Pós-Sinápticos Excitadores , Exocitose , Terminações Pré-Sinápticas/metabolismo , Membranas Sinápticas/metabolismo , Vesículas Sinápticas/metabolismo , Potenciais de Ação/efeitos dos fármacos , Animais , Tronco Encefálico/citologia , Tronco Encefálico/efeitos dos fármacos , Cálcio/metabolismo , Quelantes/farmacologia , Simulação por Computador , Capacitância Elétrica , Estimulação Elétrica , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Exocitose/efeitos dos fármacos , Técnicas In Vitro , Camundongos , Modelos Neurológicos , Neurotransmissores/farmacologia , Técnicas de Patch-Clamp , Terminações Pré-Sinápticas/efeitos dos fármacos , Membranas Sinápticas/efeitos dos fármacos , Vesículas Sinápticas/efeitos dos fármacos , Fatores de TempoRESUMO
Action potential (AP) patterns and dopamine (DA) release are known to correlate with rewarding behaviors, but how codes of AP bursts translate into DA release in vivo remains elusive. Here, a given AP pattern was defined by four codes, termed total AP number, frequency, number of AP bursts, and interburst time [N, f, b, i].. The 'burst effect' was calculated by the ratio (γ) of DA overflow by multiple bursts to that of a single burst when total AP number was fixed. By stimulating the medial forebrain bundle using AP codes at either physiological (20 Hz) or supraphysiological (80 Hz) frequencies, we found that DA was released from two kinetically distinct vesicle pools, the fast-releasable pool (FRP) and prolonged-releasable pool (PRP), in striatal dopaminergic terminals in vivo. We examined the effects of vesicle pools on AP-pattern dependent DA overflow and found, with given 'burst codes' [b=8, i=0.5 s], a large total AP number [N = 768, f = 80 Hz] produced a facilitating burst-effect (γ[b8/b1] = 126 ± 3%), while a small total AP number [N=96, 80 Hz] triggered a depressing-burst-effect (γ[b8/b1] = 29 ± 4%). Furthermore, we found that the PRP (but not the FRP) predominantly contributed to the facilitating-burst-effect and the FRP played an important role in the depressing-burst effect. Thus, our results suggest that striatal DA release captures pre-synaptic AP pattern information through different releasable pools.
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Potenciais de Ação/fisiologia , Corpo Estriado/metabolismo , Dopamina/metabolismo , Vesículas Sinápticas/fisiologia , Algoritmos , Animais , Simulação por Computador , Estimulação Elétrica , Eletroquímica , Canais Iônicos/efeitos dos fármacos , Canais Iônicos/metabolismo , Cinética , Masculino , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley , Vesículas Sinápticas/metabolismoRESUMO
Our previous observations showed that several stimuli, including high-K(+) solution, glutamate, and voltage pulses, induce somatic noradrenaline (NA) secretion from locus ceruleus (LC) neurons. Hypocretin (orexin), a hypothalamic peptide critical for normal wakefulness, has been shown to evoke NA release from the axon terminals of LC neurons. Here, we used amperometry to test the effect of hypocretin-1 (HCRT) on NMDA receptor-mediated somatodendritic release in LC neurons. Either HCRT or NMDA applied alone dose-dependently induced somatodendritic secretion. Bath application of HCRT notably potentiated NMDA receptor-mediated somatodendritic NA release. This potentiation was blocked by SB 334867, a selective HCRT receptor (Hcrtr 1) antagonist, or bisindolylmaleimide, a specific protein kinase C (PKC) inhibitor, indicating the involvement of Hcrtr 1 and PKC. Consistent with this, phorbol 12-myristate 13-acetate, a PKC activator, mimicked the HCRT-induced potentiation. Furthermore, HCRT enhanced NMDA-induced intracellular Ca(2+) elevation via activation of Hcrtr 1 and PKC, which may contribute to HCRT-potentiated somatodendritic secretion. These results suggest that HCRT modulates LC activity not only by regulating noradrenergic input to its targets, but also by affecting noradrenergic communication in the soma and dendrites.
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Dendritos/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Locus Cerúleo/citologia , Neurônios/citologia , Neuropeptídeos/farmacologia , Neurotransmissores/farmacologia , Receptores de N-Metil-D-Aspartato/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Cálcio/metabolismo , Dendritos/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Técnicas In Vitro , N-Metilaspartato/farmacologia , Orexinas , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-DawleyRESUMO
In order to investigate the central nervous mechanism and the diseases involved in catecholamine transmitter secretion, the dynamics of catecholamine release is studied in single cell, brain slice or in vivo. Noradrenaline is an important neurotransmitter and modulator in the central nervous system (CNS) and the peripheral nervous system (PNS). In the present paper, we first compared three real-time methods used to measure noradrenaline secretion in single cells (membrane capacitance, amperometry and confocal fluorescence microscopy imaging). Compared to the electrophysiological method and fluorescence microscopy, the basic usage of the carbon fiber electrode (CFE) in neuroscience research was presented as an example. Then, we presented a primary description of ion channels, including voltage-gated Na(+), K(+) and Ca(2+) channels in locus coeruleus (LC) neurons in rat brain slices. Finally, we presented example recordings of combined patch-clamp and amperometry measurements in LC neurons, indicating Ca(2+)-dependent quantal noradrenaline release following Ca(2+) influx through Ca(2+) channels.
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Sistema Nervoso Central/fisiologia , Norepinefrina/metabolismo , Animais , Canais Iônicos/fisiologia , Técnicas de Patch-Clamp , RatosRESUMO
OBJECTIVE: To study whether the substitutions at the major hydrophilic region II (MHRII) of hepatitis B surface antigen (HBsAg) will impair the antigenicity of HBsAg. METHODS: Four recombinant plasmids expressing mutant HBsAg (mtHBsAg) P1120T, C121S, K122I and T123N were constructed. HepG2 cells were transfected with the four plasmids and a plasmid expressing G145R HBsAg. The immunoreactivity of the cells expressing mtHBsAg with P1120T, C121S, K122I, T123N and G145R were detected by immunofluorescence (IF) staining and ELISA with 4 antibodies and 7 HBsAg diagnostic kits respectively. RESULTS: mtHBsAg with P120T was recognized by mAb1 and mAb2. mtHBsAg with C121S and K122I was not recognized by any mAbs. mtHBsAg with T123N in lysates was recognized by mAb2, but not recognized in the supernatants. CONCLUSION: Substitutions at amino acid positions 120-123 of HBsAg strongly impaired the antigenicity of HBsAg, a fact that was not appreciated previously.
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Variação Antigênica , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Substituição de Aminoácidos , Células Hep G2 , Vírus da Hepatite B/genética , Humanos , Mutação , Plasmídeos , TransfecçãoRESUMO
Chronic stressors can often lead to the development of psychological disorders, such as depression and anxiety. The locus coeruleus (LC) is a stress sensitive brain region located in the pons, with noradrenergic neurons that project to the hypothalamus, especially the paraventricular nucleus (PVN) of the hypothalamus. The purpose of this paper is to better understand how alpha 2A-adrenoceptors (α2A-ARs) and LC-hypothalamus noradrenergic system participate in the pathophysiological mechanism of depression. In vivo norepinephrine (NE) release in the PVN triggered by electrical stimulation in the LC was detected with carbon fiber electrodes in depression model of rats induced by chronic unpredictable mild stress (CUMS). Also, the extracellular level of NE in the PVN was measured by microdialysis in vivo without any stimulation in the LC. The alpha 2-adrenoceptor (α2-AR) antagonist yohimbine and α2A-ARs antagonist BRL-44408 maleate were systemically administered to rats to determine the effects of α2A-ARs on NE release in the PVN. The peak value of elicited NE release signals in the PVN induced by electrical stimulation in the LC in the CUMS rats were lower than that in the control rats. The extracellular levels of NE in the PVN of the CUMS rats were significantly less than that of the control rats. Intraperitoneal injection of yohimbine or BRL-44408 maleate significantly potentiated NE release in the PVN of the CUMS rats. The CUMS significantly increased protein expression levels of α2A-AR in the hypothalamus, and BRL-44408 maleate significantly reversed the increase of α2A-AR protein expression levels in the CUMS rats. Our results suggest that the CUMS could significantly facilitate the effect of α2-adrenoceptor-mediated presynaptic inhibition and decrease the release of NE in the PVN from LC. Blockade of the inhibitory action of excessive α2A-adrenergic receptors in the CUMS rats could increase the level of NE in the PVN, which is effective in the treatment of depressive disorders.
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OBJECTIVE: To investigate the function of interferon alpha (IFNalpha) in a Chinese marmot model of hepatitis B, we expressed the Chinese marmot (Marmota himalayana) IFNalpha family gene (IFNA) in eukaryotic cells and prokaryotic cells. METHODS: Eukaryotic and prokaryotic expression plasmids harboring Chinese marmot interferon alpha gene with different genotypes were generated using molecular cloning technology. We detected the biological activity of all expression products by viral protection assay, and analyzed their differences and species restriction of the biological activity. RESULTS: The Chinese marmot functional genotype IFNalpha was expressed in the baby hamster kidney (BHK) cell line, and these products protected WH12/6 cells challenged by encephalomyocarditis virus (EMCV). The Chinese marmot IFN-alpha5 also expressed in E. Coli induced by IPTG, and purified fusion protein had antiviral biological activity. The biologic activity displayed differences among different subtype IFNalpha, and it had strict species restriction. CONCLUSION: The IFNalpha family gene of the Chinese marmot can be expressed in both eukaryotic and prokaryotic cells, and the expression products show antiviral activity in a protection assay. This study provides, for the first time, evidence that IFNalpha from the Chinese marmot has an antiviral function in vitro and can be used to improve the efficacy of current therapies for HBV infection in our Chinese marmot model.
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Hepatite B/metabolismo , Interferon-alfa/biossíntese , Interferon-alfa/genética , Marmota/metabolismo , Animais , Células Eucarióticas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Interferon-alfa/fisiologia , Células Procarióticas/metabolismo , Transdução de Sinais , Fatores de TranscriçãoRESUMO
OBJECTIVE: To investigate whether the presence of HBV mutant in vaccinees simply reflects the prevalence of HBV mutant in a specific geographic area or is indeed due to the immune pressure induced by vaccination. METHODS: HBV S genes were amplified by using polymerase chain reaction (PCR) and DNA sequence analysis of the "a" determinant was performed on sera from 30 childhood patients with immunoprophylaxis and 30 patients without vaccinations. RESULTS: Mutations of the "a" determinant were detected in 8 of the 60 patients. They were all of the adw subtype. The prevalence of amino acid substitutions as detected by direct sequencing was higher in those fully-vaccinated than of those not vaccinated. In all 8 vaccinated and also with detectable mutants, the mean age was older than the other vaccinated children. CONCLUSION: The prevalence of mutants is related to HBV subtypes and genotypes. Universal vaccination has accelerated an accumulation of HBsAg "a" determinant mutants with amino acid changes critical for immune escape in vaccinated children who became carriers. This suggests that new vaccination strategies should be considered.
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Epitopos/genética , Antígenos de Superfície da Hepatite B/genética , Vacinas contra Hepatite B/imunologia , Mutação Puntual , Criança , China , Feminino , Hepatite B/prevenção & controle , Vírus da Hepatite B/genética , Humanos , Masculino , VacinaçãoRESUMO
Locus coeruleus (LC) has noradrenergic nerve terminals projecting to hypothalamus that modulating cardiovascular activity. To study the dynamic characteristics of norepinephrine (NE) release in hypothalamus followed by electrical stimulation in the locus coeruleus in the stress-induced hypertension (SIH) rats, we established the hypertension model rats by stimulations combining noise and foot-shock stress. After the end of modeling, NE release in the hypothalamus by electrical stimulation in LC was studied and NE signal was recorded by carbon fiber electrode. The peak value, the time to peak and half-life period of NE signal in both group rats were analyzed. Furthermore, to clarify the role of angiotensin II type 2 receptors (AT2) in norepinephrine (NE) release and the blood pressure of rat model of stress-induced hypertension, we intraperitoneally administered the AT2 receptor antagonist PD123319 (AT2 receptor antagonist, 0.3mg/kg, i.p.) and intracerebroventricularly injection of CGP42112 (AT2 receptor agonist, 6µg/5µl, i.c.v.) to adult male rats. We found the peak value of NE signal in the hypothalamus followed by electrical stimulation in the LC in SIH rats were higher than that in controls (P<0.01). Intraperitoneal injection of PD123319 (AT2 receptor antagonist) potentiated electrical stimulation in the LC induced NE release in the hypothalamus in SIH rats and elevated blood pressure (P<0.05), whereas intracerebroventricular injection of CGP42112 (AT2 receptor agonist) inhibited the NE release and reduced the heart rate (P<0.05). These results suggest that combining noise and foot-shock stresses increased the blood pressure and the secretion of NE in the hypothalamus followed by electrical stimulation in the LC in rats. AT2 receptors can inhibit the secretion of NE from the LC to the hypothalamus. The attenuation of presynaptic action of AT2 receptor may play a role in the pathophysiological mechanism of SIH in rats.
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Hipertensão/fisiopatologia , Locus Cerúleo/metabolismo , Locus Cerúleo/fisiopatologia , Norepinefrina/metabolismo , Receptor Tipo 2 de Angiotensina/fisiologia , Estresse Psicológico/fisiopatologia , Bloqueadores do Receptor Tipo 2 de Angiotensina II/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Hipotálamo/metabolismo , Imidazóis/farmacologia , Masculino , Oligopeptídeos/farmacologia , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor Tipo 2 de Angiotensina/agonistasRESUMO
BACKGROUND: Fibroblast growth factor receptor 4 (FGFR4) has been proved to be correlated with progression and prognosis in many cancers. However, the significance of FGFR4 in non-small-cell lung cancer (NSCLC) is still not well elucidated. METHODS: In our experiment, we detected FGFR4 expression in 237 samples of NSCLC with immunohistochemistry, and further analyzed the correlation between FGFR4 and clinicopathologic features of NSCLC with chi-square test. Moreover, we evaluated the prognostic value of FGFR4 by Kaplan-Meier survival curve and Cox regression model. By regulating the expression of FGFR4 by overexpression or knockdown, we assessed the role of FGFR4 on NSCLC cell proliferation. RESULTS: FGFR4 expression was high in NSCLC (46.8%, 111/237). FGFR4 expression was significantly associated with tumor diameter (P=0.039). With univariate (P=0.009) and multivariate (P=0.002) analysis, FGFR4 was identified as an independent prognostic factor in NSCLC (P=0.009). Moreover, FGFR4 can promote the proliferation of NSCLC cell lines. CONCLUSION: FGFR4 is an independent prognostic biomarker in NSCLC. FGFR4 can accelerate the proliferation of NSCLC cell lines, indicating FGFR4 could be a potential drug target of NSCLC.
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Norepinephrine (NE) released from the nerve terminal of locus coeruleus (LC) neurons contributes to about 70% of the total extracellular NE in primates brain. In addition, LC neurons also release NE from somatodendritic sites. Quantal NE release from soma of LC neurons has the characteristics of long latency, nerve activity-dependency, and autoinhibition by α(2)-adrenergic autoreceptor. The distinct kinetics of stimulus-secretion coupling in somata is regulated by action potential patterns. The physiological significance of soma and dendritic release is to produce negative-feedback and to down-regulate neuronal hyperactivity, which consequently inhibit NE release from axon terminal of LC projecting to many brain areas. Recent discoveries about the LC somatodendritic release may provide new insights into the pathogenesis of clinic disease involving LC-NE system dysfunction, and may help developing remedy targeted to the LC area.
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Hepatitis B virus surface antigen (HBsAg), a specific antigen on the membrane of Hepatitis B virus (HBV)-infected cells, provides a perfect target for therapeutic drugs. The development of reagents with high affinity and specificity to the HBsAg is of great significance to the early-stage diagnosis and treatment of HBV infection. Herein, we report the selection of RNA aptamers that can specifically bind to HBsAg protein and HBsAg-positive hepatocytes. One high affinity aptamer, HBs-A22, was isolated from an initial 115 mer library of ~1.1 x 10¹5 random-sequence RNA molecules using the SELEX procedure. The selected aptamer HBs-A22 bound specifically to hepatoma cell line HepG2.2.15 that expresses HBsAg but did not bind to HBsAg-devoid HepG2 cells. This is the first reported RNA aptamer which could bind to a HBV specific antigen. This newly isolated aptamer could be modified to deliver imaging, diagnostic, and therapeutic agents targeted at HBV-infected cells.
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Aptâmeros de Nucleotídeos/metabolismo , Antígenos de Superfície da Hepatite B/análise , Hepatite B/diagnóstico , Hepatócitos/química , Hepatócitos/virologia , Aptâmeros de Nucleotídeos/isolamento & purificação , Linhagem Celular , Humanos , Ligação Proteica , Técnica de Seleção de Aptâmeros , Sensibilidade e EspecificidadeRESUMO
AIM: To prepare and identify mouse polyclonal antibody against protein H1b, which is the variant of major subunit of human ASGPR. METHODS: H1b specific peptide was synthesized and coupled with keyhole limpet hemocyanin (KLH) for immunization. Then H1b-KLH conjugation was injected into mouse subcutaneously to produce polyclonal antibody. ELISA assay was used to detect the titer of the antibody. Antibody was also identified by Western blot and immunohistochemistry assays. RESULTS: Mouse antibody against H1b was prepared after injection of H1b-KLH conjugation. The titer of H1b antibody was about 1:10(5). Western blot confirmed its high specificity. This antibody could also be used for immunohistochemistry analysis. CONCLUSION: The successful preparation of the polyclonal antibody against protein H1b, which can discriminate the two variants of the major subunit of ASGPR with high specificity, will provide an efficient reagent for further study of the physiologic functions of H1b and its role in the pathogenesis of human disease.