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1.
Cell Calcium ; 101: 102514, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896700

RESUMO

CD38 is a single-pass transmembrane enzyme catalyzing the synthesis of two nucleotide second messengers, cyclic ADP-ribose (cADPR) from NAD and nicotinic acid adenine dinucleotide phosphate (NAADP) from NADP. The former mediates the mobilization of the endoplasmic Ca2+-stores in response to a wide range of stimuli, while NAADP targets the endo-lysosomal stores. CD38 not only possesses multiple enzymatic activities, it also exists in two opposite membrane orientations. Type III CD38 has the catalytic domain facing the cytosol and is responsible for producing cellular cADPR. The type II CD38 has an opposite orientation and is serving as a surface receptor mediating extracellular functions such as cell adhesion and lymphocyte activation. Its ecto-NADase activity also contributes to the recycling of external NAD released by apoptosis. Endocytosis can deliver surface type II CD38 to endo-lysosomes, which acidic environment favors the production of NAADP. This article reviews the rationale and evidence that have led to CD38 as a paradigm for membrane topology defining distinct functions of proteins. Also described is the recent discovery of a hitherto unknown cADPR-synthesizing enzyme, SARM1, ushering in a new frontier in cADPR-mediated Ca2+-signaling.


Assuntos
Sinalização do Cálcio , Cálcio , ADP-Ribosil Ciclase 1/metabolismo , Cálcio/metabolismo , ADP-Ribose Cíclica/metabolismo , Lisossomos/metabolismo , NADP/metabolismo
2.
J Inflamm Res ; 14: 4399-4407, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34511974

RESUMO

BACKGROUND AND PURPOSE: This study aimed to explore several peripheral blood-based markers related to the inflammatory response in a total of 210 patients with acute ischemic stroke (AIS) caused by large artery occlusion in the anterior circulation who received endovascular therapy (EVT) from an observational study of clinical significance of circulating non-coding RNA in acute ischemic stroke (AISRNA). METHODS: We collected baseline characteristics of 210 AIS patients participating in an observational acute stroke cohort: the AISRNA study. The following inflammatory factors were measured in these participants: interleukin-2 [IL-2], IL-4, IL-6, IL-10, tumor necrosis factor-α [TNF-α], and interferon-γ [IFN-γ]. The National Institute of Health Stroke Scale score increase of ≥4 within 24 hours after EVT defined as early neurological deterioration (END). RESULTS: Compared with patients without END, patients with END had a higher incidence of atrial fibrillation (P=0.012), and also had higher levels of IL-6 and IL-10 (P<0.01). Furthermore, we found that the area under the curves (AUCs) of IL-6 and IL-10 for predicting END were 0.768 (0.697-0.829), and 0.647 (0.570-0.719), respectively. Adjusting for age, sex, and atrial fibrillation, the odds ratios (ORs; 95% confidence interval) for incident END for IL-6 and IL-10 were 1.98 (1.05-6.69) and 1.18 (1.04-1.33), respectively. Additionally, we found significant changes over time in the expression levels of IL-4, IL-6, and IL-10 in patients with END compared with patients without END (P<0.05). CONCLUSION: IL-6 and IL-10 levels at admission may be potential markers of END after EVT, and the time course of IL-4, IL-6, and IL-10 is correlated with stroke progression. Further larger studies are needed to confirm the current findings. TRIAL REGISTRATION: ClinicalTrials.gov NCT04175691. Registered November 21, 2019, https://www.clinicaltrials.gov/ct2/show/NCT04175691.

3.
Chem Commun (Camb) ; 57(12): 1434-1437, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33514953

RESUMO

A novel nanobody-drug conjugate (NDC) was constructed by incorporating an amphipathic peptide, GALA, which improved the cytotoxicity by one to two orders of magnitude. Mechanistic studies demonstrate that tethering to lipids induces GALA to form a helix, which dramatically enhances endocytosis. Our work provides a general strategy not only for improving the anti-cancer efficacy of protein-drug conjugates but also for increasing the efficiency of other types of endocytosis-dependent cell delivery.


Assuntos
Nanoconjugados/química , Oligopeptídeos/farmacologia , Peptídeos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Oligopeptídeos/química , Proteínas Recombinantes , Anticorpos de Cadeia Única/química
4.
Br J Anaesth ; 124(3): 324-335, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32007240

RESUMO

BACKGROUND: The debate on lung-protective ventilation strategies for surgical patients is ongoing. Evidence suggests that the use of low tidal volume VT improves clinical outcomes. However, the optimal levels of PEEP and recruitment manoeuvre (RM) strategies incorporated into low VT ventilation remain unclear. METHODS: Several electronic databases were searched to identify RCTs that focused on comparison between low VT strategy and conventional mechanical ventilation (CMV), or between two different low VT strategies in surgical patients. The primary outcome was postoperative pulmonary complications (PPCs). The secondary outcomes were atelectasis, pneumonia, acute respiratory distress syndrome, and short-term mortality. Bayesian network meta-analyses were performed using WinBUGS. The odds ratios (ORs) and corresponding 95% credible intervals (CrIs) were estimated. RESULTS: Compared with CMV, low VT ventilation with moderate-to-high PEEP reduced the risk of PPCs (moderate PEEP [5-8 cm H2O]: OR 0.50 [95% CrI: 0.28, 0.89]; moderate PEEP+RMs: 0.39 [0.19, 0.78]; and high PEEP [≥9 cm H2O]+RMs: 0.34 [0.14, 0.79]). Low VT ventilation with moderate-to-high PEEP and RMs also specifically reduced the risk of atelectasis compared with CMV (moderate PEEP+RMs: OR 0.36 [95% CrI: 0.16, 0.87]; and high PEEP+RMs: 0.41 [0.15, 0.97]), whilst low VT ventilation with moderate PEEP was superior to CMV in reducing the risk of pneumonia (OR 0.46 [95% CrI: 0.15, 0.94]). CONCLUSIONS: The combination of low VT ventilation and moderate-to-high PEEP (≥5 cm H2O) seems to confer lung protection in surgical patients undergoing general anaesthesia. CLINICAL TRIAL REGISTRATION: PROSPERO (CRD42019144561).


Assuntos
Pneumopatias/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Respiração Artificial/métodos , Teorema de Bayes , Humanos , Pneumopatias/etiologia , Pneumonia/etiologia , Pneumonia/prevenção & controle , Respiração com Pressão Positiva/métodos , Atelectasia Pulmonar/etiologia , Atelectasia Pulmonar/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Respiração Artificial/efeitos adversos , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/prevenção & controle , Volume de Ventilação Pulmonar
5.
J Biol Chem ; 294(42): 15293-15303, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31434741

RESUMO

The CD38 molecule (CD38) catalyzes biogenesis of the calcium-mobilizing messenger cyclic ADP-ribose (cADPR). CD38 has dual membrane orientations, and type III CD38, with its catalytic domain facing the cytosol, has low abundance but is efficient in cyclizing cytosolic NAD to produce cADPR. The role of cell surface type II CD38 in cellular cADPR production is unknown. Here we modulated type II CD38 expression and assessed the effects of this modulation on cADPR levels. We developed a photoactivatable cross-linking probe based on a CD38 nanobody, and, combining it with MS analysis, we discovered that cell surface CD38 interacts with CD71. CD71 knockdown increased CD38 levels, and CD38 knockout reciprocally increased CD71, and both could be cocapped and coimmunoprecipitated. We constructed a chimera comprising the N-terminal segment of CD71 and a CD38 nanobody to mimic CD71's ligand property. Overexpression of this chimera induced a dramatically large decrease in CD38 via lysosomes. Remarkably, cellular cADPR levels did not decrease correspondingly. Bafilomycin-mediated blockade of lysosomal degradation greatly elevated active type II CD38 by trapping it in the lysosomes but also did not increase cADPR levels. Retention of type II CD38 in the endoplasmic reticulum (ER) by expressing an ER construct that prevented its transport to the cell surface likewise did not change cADPR levels. These results provide first and direct evidence that cADPR biogenesis occurs in the cytosol and is catalyzed mainly by type III CD38 and that type II CD38, compartmentalized in the ER or lysosomes or on the cell surface, contributes only minimally to cADPR biogenesis.


Assuntos
Antígenos CD/metabolismo , ADP-Ribose Cíclica/metabolismo , Receptores da Transferrina/metabolismo , ADP-Ribosil Ciclase 1/genética , ADP-Ribosil Ciclase 1/metabolismo , Antígenos CD/genética , Cálcio/metabolismo , Membrana Celular/genética , Membrana Celular/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , Citosol/metabolismo , Células HEK293 , Humanos , Ligação Proteica , Receptores da Transferrina/genética
6.
Crit Care ; 22(1): 298, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30428928

RESUMO

BACKGROUND: Whether goal-directed fluid therapy based on dynamic predictors of fluid responsiveness (GDFTdyn) alone improves clinical outcomes in comparison with standard fluid therapy among patients undergoing surgery remains unclear. METHODS: PubMed, EMBASE, the Cochrane Library and ClinicalTrials.gov were searched for relevant studies. Studies comparing the effects of GDFTdyn with that of standard fluid therapy on clinical outcomes among adult patients undergoing surgery were considered eligible. Two analyses were performed separately: GDFTdyn alone versus standard fluid therapy and GDFTdyn with other optimization goals versus standard fluid therapy. The primary outcomes were short-term mortality and overall morbidity, while the secondary outcomes were serum lactate concentration, organ-specific morbidity, and length of stay in the intensive care unit (ICU) and in hospital. RESULTS: We included 37 studies with 2910 patients. Although GDFTdyn alone lowered serum lactate concentration (mean difference (MD) - 0.21 mmol/L, 95% confidence interval (CI) (- 0.39, - 0.03), P = 0.02), no significant difference was found between groups in short-term mortality (odds ratio (OR) 0.85, 95% CI (0.32, 2.24), P = 0.74), overall morbidity (OR 1.03, 95% CI (0.31, 3.37), P = 0.97), organ-specific morbidity, or length of stay in the ICU and in hospital. Analysis of trials involving the combination of GDFTdyn and other optimization goals (mainly cardiac output (CO) or cardiac index (CIx)) showed a significant reduction in short-term mortality (OR 0.45, 95% CI (0.24, 0.85), P = 0.01), overall morbidity (OR 0.41, 95% CI (0.28, 0.58), P < 0.00001), serum lactate concentration (MD - 0.60 mmol/L, 95% CI (- 1.04, - 0.15), P = 0.009), cardiopulmonary complications (cardiac arrhythmia (OR 0.58, 95% CI (0.37, 0.92), P = 0.02), myocardial infarction (OR 0.35, 95% CI (0.16, 0.76), P = 0.008), heart failure/cardiovascular dysfunction (OR 0.31, 95% CI (0.14, 0.67), P = 0.003), acute lung injury/acute respiratory distress syndrome (OR 0.13, 95% CI (0.02, 0.74), P = 0.02), pneumonia (OR 0.4, 95% CI (0.24, 0.65), P = 0.0002)), length of stay in the ICU (MD - 0.77 days, 95% CI (- 1.07, - 0.46), P < 0.00001) and in hospital (MD - 1.18 days, 95% CI (- 1.90, - 0.46), P = 0.001). CONCLUSIONS: It was not the optimization of fluid responsiveness by GDFTdyn alone but rather the optimization of tissue and organ perfusion by GDFTdyn and other optimization goals that benefited patients undergoing surgery. Patients managed with the combination of GDFTdyn and CO/CI goals might derive most benefit.


Assuntos
Hidratação/métodos , Resultado do Tratamento , Hidratação/normas , Hidratação/tendências , Mortalidade Hospitalar/tendências , Humanos , Tempo de Internação , Planejamento de Assistência ao Paciente
7.
Emerg Microbes Infect ; 7(1): 139, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30068997

RESUMO

This study investigated the characteristics and mechanisms of eravacycline resistance and heteroresistance in clinical Klebsiella pneumoniae isolates. A total of 393 clinical K. pneumoniae isolates were collected and subjected to eravacycline and tigecycline MIC determinations using the agar dilution method. Eravacycline heteroresistance was assessed by a population analysis profile (PAP). The expression levels of efflux pumps and their regulators were determined by quantitative reverse-transcription PCR (qRT-PCR). This study identified 67 eravacycline-nonsusceptible isolates; among the extended-spectrum ß-lactamase (ESBL)-positive isolates, eravacycline-nonsusceptible isolates were detected more frequently than tigecycline-nonsusceptible isolates (21.7% vs. 9.4%, p = 0.001). The study sample was observed to include 20 K. pneumoniae isolates with eravacycline heteroresistance. Compared to the reference strain, oqxA or oqxB overexpression was observed in nine eravacycline-nonsusceptible isolates (range, 35.64-309.02-fold) and 13 eravacycline-heteroresistant isolates (8.42-296.34-fold). The overexpression of macA or macB was detected in 12 eravacycline-heteroresistant isolates (3.23-28.35-fold). Overexpression of the efflux pump regulator gene ramA was observed in 11 eravacycline-nonsusceptible isolates (3.33-94.05-fold) and 18 eravacycline-heteroresistant isolates (3.89-571.70-fold). The eravacycline MICs were increased by one-fourfold by overexpression of oqxAB or macAB in three eravacycline-sensitive isolates. In conclusion, the overexpression of OqxAB and MacAB efflux pumps and the transcriptional regulator RamA were suggested to be involved in K. pneumoniae eravacycline resistance and heteroresistance.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/metabolismo , Tetraciclinas/farmacologia , Transportadores de Cassetes de Ligação de ATP/genética , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/metabolismo
8.
J Neuroinflammation ; 15(1): 102, 2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29636059

RESUMO

BACKGROUND: Stroke-induced immunodeficiency syndrome (SIDS) is regarded as a protective mechanism for secondary inflammatory injury as well as a contributor to infection complications. Although stroke-induced hyperactivation of the sympathetic system is proved to facilitate SIDS, the involved endogenous factors and pathways are largely elusive. In this study, we aim to investigate the function of beta-arrestin-2 (ARRB2) in the sympathetic-mediated SIDS. METHODS: Splenic ARRB2 expression and the sympathetic system activity were detected after establishing transient models of middle cerebral artery occlusion (MCAO). In addition, a correlation between ARRB2 expression and the sympathetic system activity was analyzed using a linear correlation analysis. Any SIDS reflected in monocyte dysfunction was investigated by measuring inflammatory cytokine secretion and neurological deficit scores and infarct volume were tested to assess neurological outcome. Further, ARRB2 expression in the monocytes was knocked down in vitro by siRNAs. Following the stimulation of noradrenaline and lipopolysaccharide, cytokine secretion and the nuclear factor-κB (NF-κB) pathway were evaluated to gain insight into the mechanisms related to the contribution of ARRB2 to adrenergic-induced monocyte dysfunction. RESULTS: Splenic ARRB2 expression was significantly increased after stroke and also showed a significant positive correlation with the sympathetic system activity. Stroke-induced monocyte dysfunction resulted in an increase of the interleukin-10 (IL-10) level as well as a decrease of the interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) levels. Also, blockade of adrenergic-activity significantly reversed these cytokine levels, and blockade of adrenergic-activity improved stroke-induced neurological results. However, the improved neurological results had no significant correlation with ARRB2 expression. Furthermore, the in vitro results showed that the deficiency of ARRB2 dramatically repealed adrenergic-induced monocyte dysfunction and the inhibition of NF-κB signaling phosphorylation activity. CONCLUSIONS: ARRB2 is implicated in the sympathetic-triggered SIDS, in particular, monocyte dysfunction after stroke. Accordingly, ARRB2 may be a promising therapeutic target for the immunological management of stroke in a clinic.


Assuntos
Regulação da Expressão Gênica/fisiologia , Síndromes de Imunodeficiência/etiologia , Síndromes de Imunodeficiência/patologia , Infarto da Artéria Cerebral Média/complicações , Sistema Nervoso Simpático/fisiopatologia , beta-Arrestina 2/metabolismo , Animais , Infarto Encefálico/etiologia , Linhagem Celular Transformada , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Macrófagos , Masculino , Monócitos/metabolismo , Exame Neurológico , Propranolol/farmacologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Sistema Nervoso Simpático/imunologia , Transfecção , Vasodilatadores/farmacologia , beta-Arrestina 2/genética
9.
J Biol Chem ; 293(21): 8151-8160, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29632067

RESUMO

Nicotinic acid adenosine dinucleotide phosphate (NAADP) is a Ca2+-mobilizing second messenger that regulates a wide range of biological activities. However, the mechanism of its biogenesis remains controversial. CD38 is the only enzyme known to catalyze NAADP synthesis from NADP and nicotinic acid. CD38-mediated catalysis requires an acidic pH, suggesting that NAADP may be produced in acidic endolysosomes, but this hypothesis is untested. In this study, using human cell lines, we specifically directed CD38 to the endolysosomal system and assessed cellular NAADP production. First, we found that nanobodies targeting various epitopes on the C-terminal domain of CD38 could bind to cell surface-localized CD38 and induce its endocytosis. We also found that CD38 internalization occurred via a clathrin-dependent pathway, delivered CD38 to the endolysosome, and elevated intracellular NAADP levels. We also created a CD38 variant for lysosome-specific expression, which not only withstood the degradative environment in the lysosome, but was also much more active than WT CD38 in elevating cellular NAADP levels. Supplementing CD38-expressing cells with nicotinic acid substantially increased cellular NAADP levels. These results demonstrate that endolysosomal CD38 can produce NAADP in human cells. They further suggest that CD38's compartmentalization to the lysosome may allow for its regulation via substrate access, rather than enzyme activation, thereby providing a reliable mechanism for regulating cellular NAADP production.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Cálcio/metabolismo , Endocitose , Lisossomos/metabolismo , Glicoproteínas de Membrana/metabolismo , NADP/análogos & derivados , ADP-Ribosil Ciclase 1/genética , Sinalização do Cálcio , Células HEK293 , Células HeLa , Humanos , Glicoproteínas de Membrana/genética , NADP/metabolismo , Niacina/farmacologia , Anticorpos de Domínio Único/administração & dosagem , Vasodilatadores/farmacologia
10.
J Crit Care ; 42: 294-303, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28820981

RESUMO

PURPOSE: We aimed to seek risk factors for AMI among adult patients undergoing cardiac surgery. MATERIALS AND METHODS: We searched electronic bibliographic databases for studies reporting risk factors for AMI among adult patients undergoing cardiac surgery. Pooled odds ratios (OR) and standard mean differences (SMD or MD) for risk factors between AMI and control group were estimated. RESULTS: 11 studies with 67,195 patients met the inclusion criteria. 14 risk factors were found to be statistically significant: preoperative factors including age (MD 4.62years, 95% CI (1.97,7.27)), cardiac shock (OR 5.17, (1.17,22.81)), peripheral vascular disease (OR 3.53, (2.05,6.09)), need for intra-aortic balloon pump (IABP) (OR 5.89, (3.26,10.65)), emergency surgery (OR 3.75, (1.69,8.33)), and postoperative factors including atrial fibrillation (OR 2.41, (1.79,3.24)), CK-MB level (SMD 1.06, (0.62 to 1.50)), serum creatinine >200µmol/L (OR 23.39, (11.61,47.12)), blood loss (MD 358.32mL, (53.56,663.07)), prolonged ventilation (OR 9.04, (5.24,15.62)), need for IABP (OR 6.32, (3.19,12.54)), inotropic treatment (OR 8.40, (3.19,22.14)), blood transfusion (OR 9.15, (4.79,17.48)), reoperation (OR 3.30, (1.55,7.04)). CONCLUSIONS: 14 risk factors were associated with an increased risk of AMI, which indicated that AMI might occur via stenosis or occlusion of mesenteric vessels, reduced blood volume or maldistribution of blood flow.


Assuntos
Procedimentos Cirúrgicos Cardíacos/mortalidade , Balão Intra-Aórtico , Isquemia Mesentérica/prevenção & controle , Fibrilação Atrial , Hemorragia , Humanos , Complicações Pós-Operatórias/prevenção & controle , Fatores de Risco
11.
Chest ; 151(1): 149-159, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27729264

RESUMO

BACKGROUND: Postoperative atrial fibrillation/flutter (POAF) is associated with significant morbidity and mortality after general thoracic surgery, but the need for and the best agent for prophylaxis remains obscure. METHODS: A systematic literature search was performed to identify randomized controlled trials that compared regimens for POAF prophylaxis after general thoracic surgery. Random-effects meta-analyses with trial sequential analyses were performed to compare the effects of medical prophylaxis vs placebo/usual care. The risk of POAF among patients receiving various prophylactic regimens was subjected to Bayesian network meta-analysis. RESULTS: Twenty-two trials (2,891 patients and 11 regimens) were included. Overall, medical prophylaxis reduced the incidence of POAF (OR, 0.33; 95% CI, 0.22-0.49) but not short-term mortality (OR, 0.85; 95% CI, 0.41-1.73). There was no significant difference in patient withdrawal due to adverse events (OR, 1.67; 95% CI, 0.67-4.16). Trial sequential analysis showed that as of 2012, sufficient evidence had accrued in support of the effectiveness of medical prophylaxis in reducing POAF after general thoracic surgery. In network meta-analysis, ß-blockers, angiotensin-converting enzyme inhibitors, amiodarone, magnesium, and calcium channel blockers significantly reduced the risk of POAF compared with placebo/usual care. ß-Blockers had the highest probability of being the most effective agents (OR, 0.12; 95% credible interval [CrI], 0.05-0.27; probability of being best, 77.7%; number needed to treat, 5.2). CONCLUSIONS: The current literature supports the effectiveness and tolerability of medical prophylaxis and the superiority of ß-blockers in preventing POAF after general thoracic surgery. ß-Blockers are recommended, taking into consideration the status of the bronchopulmonary system.


Assuntos
Antiarrítmicos , Fibrilação Atrial , Complicações Pós-Operatórias , Procedimentos Cirúrgicos Torácicos/efeitos adversos , Antiarrítmicos/classificação , Antiarrítmicos/farmacologia , Fibrilação Atrial/etiologia , Fibrilação Atrial/prevenção & controle , Humanos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Resultado do Tratamento
12.
Oncotarget ; 7(32): 52404-52415, 2016 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-27409177

RESUMO

BACKGROUND: Evidence has led to the consideration of immunodepression after stroke as an important contributor to stroke associated infection (SAI). However, so far no specific immunological indicator has been identified for SAI, and the underlying mechanism remains poorly understood. RESULTS: SAI patients had significantly higher IL-6 and IL-10 levels and lower HLA-DR levels than no-infection patients within 48h after stroke onset. NA significantly increased IL-10 levels, reduced HLA-DR expression, and decreased IL-6 expression by increasing ß-arrestin2 expression which reduced the activation of the NF-κB pathway. Propranolol reversed this effect of NA by reducing ß-arrestin2 expression. MATERIALS AND METHODS: A systematic search for eligible clinical studies was applied to pool the differences in peripheral cytokine levels between infection and no-infection stroke patients. The underlying mechanism behind these differences was investigated in vitro by applying norepinephrine (NA) and lipopolysaccharide (LPS) to simulate sympathetic pathway activation and sepsis respectively in THP-1 cells. Propranolol was applied to determine the effect of reversing the activation of the sympathetic pathway. Immunological indicators were also detected to assess the immune activation of THP-1 cells and measurements of the expression of ß-arrestin2, NF-κB, IκBα and phosphor-IκBα were performed to assess the activation of the sympathetic pathway. CONCLUSION: IL-6, IL-10 and HLA-DR are good candidate biomarkers for SAI. The activation of the sympathetic pathway could partly account for the specific immunological alterations found in SAI patients including HLA-DR decrease and IL-10 increase, which both could be reversed by propranolol. However, the mechanism underlying IL-6 increase still needs further exploration.


Assuntos
Antígenos HLA-DR/biossíntese , Infecções/imunologia , Interleucina-10/biossíntese , Interleucina-6/biossíntese , Acidente Vascular Cerebral/complicações , Antagonistas Adrenérgicos beta/farmacologia , Biomarcadores/análise , Linhagem Celular , Antígenos HLA-DR/imunologia , Humanos , Tolerância Imunológica/fisiologia , Interleucina-10/imunologia , Interleucina-6/imunologia , Propranolol/farmacologia , Acidente Vascular Cerebral/imunologia , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/imunologia
13.
Sci Rep ; 6: 27055, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27251573

RESUMO

CD38, as a cell surface antigen is highly expressed in several hematologic malignancies including multiple myeloma (MM) and has been proven to be a good target for immunotherapy of the disease. CD38 is also a signaling enzyme responsible for the metabolism of two novel calcium messenger molecules. To be able to target this multifunctional protein, we generated a series of nanobodies against CD38 with high affinities. Crystal structures of the complexes of CD38 with the nanobodies were solved, identifying three separate epitopes on the carboxyl domain. Chromobodies, engineered by tagging the nanobody with fluorescence proteins, provide fast, simple and versatile tools for quantifying CD38 expression. Results confirmed that CD38 was highly expressed in malignant MM cells compared with normal white blood cells. The immunotoxin constructed by splicing the nanobody with a bacterial toxin, PE38 shows highly selective cytotoxicity against patient-derived MM cells as well as the cell lines, with half maximal effective concentration reaching as low as 10(-11) molar. The effectiveness of the immunotoxin can be further increased by stimulating CD38 expression using retinoid acid. These results set the stage for the development of clinical therapeutics as well as diagnostic screening for myeloma.


Assuntos
ADP-Ribosil Ciclase 1/imunologia , Antineoplásicos Imunológicos/química , Glicoproteínas de Membrana/imunologia , Anticorpos de Domínio Único/química , ADP-Ribosil Ciclase 1/metabolismo , Sequência de Aminoácidos , Especificidade de Anticorpos , Antineoplásicos Imunológicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Glicoproteínas de Membrana/metabolismo , Modelos Moleculares , Mieloma Múltiplo/tratamento farmacológico , Ligação Proteica , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Anticorpos de Domínio Único/farmacologia
14.
Curr Microbiol ; 73(3): 361-365, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27246497

RESUMO

Enteropathogenic Escherichia coli (EPEC) is a major cause of infantile diarrhea in developing countries. The translocator EspB is a key virulence factor in the process of the attaching and effacing effect of EPEC and plays a critical role in the pathogenesis of the bacteria. In this study, we aimed to select the peptides binding to EspB protein by phage display library and further investigate whether these peptides can decrease the extent of invasion and virulence of EPEC on host cells by targeting to EspB protein. The expression and purification of EspB protein from E. coli was demonstrated by Western blotting. The Ph.D. 12-mer peptide phage display library was used to screen the candidate peptides binding specifically to EspB protein. Furthermore, the affinity of these candidate peptides bound to EspB was identified by enzyme-linked immunosorbent assay (ELISA). Moreover, we investigated whether these screened peptides could decrease the adherence ratio of EPEC to HEp-2 cells with increasing concentration. Successful purification of EspB protein from pET21b-EspB-transformed E. coli was identified by Western blotting. Then, the candidate peptides including phages 6, 7, 8, and 12 were screened by the Ph.D. 12-mer peptide phage display library and ELISA test demonstrated that their affinity binding to EspB protein was high compared with the control. Functional analysis indicated that synthetic peptide-6 (YFPYSHTSPRQP) significantly decreased the adherence ratio of EPEC to HEp-2 cells with increasing concentration (P < 0.01). Peptide-6 (100 µg/mL) could lead to a 40 % decrease in the adherence ratio of EPEC to HEp-2 cells compared with control (P < 0.01). However, the other three peptides at different concentrations showed only a slight ability to block the adherence of EPEC to host cells. Our data provided a potential strategy to inhibit the adhesion of EPEC to epithelial cells by a candidate peptide targeted toward EspB protein.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Proteínas da Membrana Bacteriana Externa/antagonistas & inibidores , Escherichia coli Enteropatogênica/fisiologia , Células Epiteliais/microbiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/antagonistas & inibidores , Peptídeos/farmacologia , Sequência de Aminoácidos , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Escherichia coli Enteropatogênica/efeitos dos fármacos , Escherichia coli Enteropatogênica/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Células Hep G2 , Humanos , Dados de Sequência Molecular , Peptídeos/química
15.
Int J Gynecol Cancer ; 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27101587

RESUMO

OBJECTIVE: Early diagnosis of ovarian cancer is crucial in clinical practice but is difficult. Accumulating studies have investigated the utility of YKL-40 in early detection of ovarian cancer. The aim of this study was to evaluate the overall accuracy of YKL-40 in diagnosis of ovarian cancer through a meta-analysis of published studies. METHODS: A comprehensive search of related literature was performed in PubMed, Web of Science, and China National Knowledge Infrastructure databases. Meta-DiSc 1.4 and STATA 11.0 were selected for data analysis, and Quality Assessment of Diagnostic Accuracy Studies tool version 2 was used to assess the quality of included studies. Data from selected studies were pooled to yield summary sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio, and summary receiver operating characteristic curve. RESULTS: A total of 13 studies dating up to May 2015 with 1623 individuals were enrolled in the present study. The pooled characteristics of these studies were as follows: sensitivity 0.71 (95% confidence interval [CI], 0.68-0.75), specificity 0.90 (95% CI, 0.88-0.92), positive likelihood ratio 7.24 (95% CI, 4.22-12.43), negative likelihood ratio 0.34 (95% CI, 0.27-0.42), and diagnostic odds ratio 24.93 (95% CI, 12.61-49.27), respectively. The area under the curve was 0.8471. CONCLUSIONS: The results indicated that YKL-40 could be regarded as an effective biomarker for diagnosis of ovarian cancer.

16.
Neurochem Res ; 41(8): 1877-86, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27059792

RESUMO

Stoke results in activation of the sympathetic nervous system (SNS), inducing systemic immunosuppression. However, the potential mechanisms underlying stroke-induced immunosuppression remain unclear. Here, we determined the SNS effects on functional outcome and explored the interactions among SNS, ß-arrestin2 and nuclear factor-κB (NF-κB) after experimental stroke in rats. In the current study, stroke was induced by a transient middle cerebral artery occlusion (MCAO) in rats, and SNS activity was inhibited by intraperitoneal injection of 6-hydroxydopamine HBr (6-OHDA). 7.0 T Micro-MRI and Longa score were employed to assess the functional outcome after stroke. Flow cytometry and ELISA assay were used to measure the expression of MHC class II, tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Western blot was conducted to analyze ß-arrestin2 and NF-κB protein expression levels after experimental stroke. We found significantly increased infarct volumes and functional impairment after MCAO at different post-surgery time points, which were not aggravated by 6-OHDA treatment. SNS blockade partially reversed the expression of MHC class II after stroke over time, as well as TNF-α and IFN-γ levels in lipopolysaccharide-stimulated macrophages in vitro. Treatment of MCAO rats with SNS-inhibitor significantly diminished NF-κB activation and enhanced ß-arrestin2 expression after stroke. This study suggests that pharmacological SNS inhibition dose not aggravate functional outcome after stroke. Stroke-induced immunosuppression may be involved in the SNS-ß-arrestin2-NF-κB pathway.


Assuntos
Terapia de Imunossupressão/métodos , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/imunologia , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/imunologia , Animais , Masculino , Oxidopamina/farmacologia , Oxidopamina/toxicidade , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Acidente Vascular Cerebral/metabolismo , Sistema Nervoso Simpático/metabolismo , Resultado do Tratamento
18.
Gene ; 573(1): 160-5, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26190157

RESUMO

Polymorphisms in microRNA (miRNA) binding site have been widely discussed to be associated with cancer risk; however, the associations were unclear in Chinese population. To investigate the associations of five polymorphisms (rs11097457, rs1434536, rs1970801, rs1044129, rs11169571) in miRNA binding sites with breast cancer risk, a total of 435 female patients with breast cancer and 439 age- and gender-matched tumor-free individuals were enrolled in this case-control study. Sequenom MassARRAY was applied to detect the polymorphisms, and the immunohistochemistry assay was used to measure the expression of estrogen receptor (ER) and progesterone receptor (PR) and CerbB-2. The data showed that these polymorphisms were not associated with breast cancer risk or clinical characters of breast cancer in all participants and sub-group with the exception that, in the sub-group of women with their first menstruation after 14 years old, those who carried rs1970801 T allele (genotype TT/GT) were associated with decreased breast cancer risk. In short, this case-control study provided the evidence that women with their first menstruation after 14 years old and carried rs1970801 T allele (genotype TT/GT) were associated with decreased breast cancer risk.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , MicroRNAs/metabolismo , Polimorfismo de Nucleotídeo Único , Adulto , Sítios de Ligação , Estudos de Casos e Controles , China , Feminino , Humanos , MicroRNAs/genética , Pessoa de Meia-Idade
19.
Sci Rep ; 5: 11348, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26076815

RESUMO

A common deletion polymorphism within B-cell chronic lymphocytic leukemia-lymphoma like 11 gene (BIM) was deemed to be a genetic cause leading to compromised kinase inhibitor therapeutic efficacy in cancer individuals. However, the results reported were not consistent. Thus, a comprehensive meta-analysis containing 12 eligible studies including 1,532 Asian patients was conducted to investigate a steady and reliable conclusion. The results showed that BIM deletion polymorphism was significantly associated with tyrosine kinase inhibitor (TKI) clinical efficacy in term of response rate (Ph = 0.349, HR = 0.438, 95%CI = 0.274-0.699) and disease control rate (Ph = 0.941, HR = 0.370, 95%CI = 0.202-0.678) in EGFR-mutated NSCLC population, not in CML and HCC subgroups. Additionally, EGFR-mutated NSCLC patient harbored BIM deletion polymorphism was associated with a shorter progression-free survival (PFS) than those with BIM wild polymorphism (Ph = 0.580, adjusted HR = 2.194, 95%CI = 1.710-2.814). However, no significant association was examined between BIM deletion polymorphism and overall survival (OS) and toxic adverse events in EGFR-mutated NSCLC population and it was not associated with PFS and OS in HCC subgroup. These findings revealed that BIM deletion polymorphism might be a genetic cause of intrinsic resistance to TKI therapy and it could be emerged as an independent predictor to identify patients who would benefit from TKI targeted therapy in EGFR-mutated NSCLC.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Carcinoma Hepatocelular/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteínas de Membrana/genética , Neoplasias/genética , Polimorfismo Genético , Proteínas Proto-Oncogênicas/genética , Antineoplásicos/uso terapêutico , Proteínas Reguladoras de Apoptose/deficiência , Proteína 11 Semelhante a Bcl-2 , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas de Membrana/deficiência , Neoplasias/tratamento farmacológico , Neoplasias/mortalidade , Neoplasias/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas/deficiência , Deleção de Sequência , Transdução de Sinais , Análise de Sobrevida , Resultado do Tratamento
20.
Oncotarget ; 6(10): 7899-917, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25760077

RESUMO

The long non-coding RNA (lncRNA) urothelial carcinoma-associated 1 (UCA1) has been recently shown to be dysregulated, which plays an important role in the progression of several cancers. However, the biological role and clinical significance of UCA1 in the carcinogenesis of hepatocellular carcinoma (HCC) remain unclear. Herein, we found that UCA1 was aberrantly upregulated in HCC tissues and associated with TNM stage, metastasis and postoperative survival. UCA1 depletion inhibited the growth and metastasis of HCC cell lines in vitro and in vivo. Furthermore, UCA1 could act as an endogenous sponge by directly binding to miR-216b and downregulation miR-216b expression. In addition, UCA1 could reverse the inhibitory effect of miR-216b on the growth and metastasis of HCC cells, which might be involved in the derepression of fibroblast growth factor receptor 1 (FGFR1) expression, a target gene of miR-216b, and the activation of ERK signaling pathway. Taken together, our data highlights the pivotal role of UCA1 in the tumorigenesis of HCC. Moreover, the present study elucidates a novel lncRNA-miRNA-mRNA regulatory network that is UCA1-miR-216b-FGFR1-ERK signaling pathway in HCC, which may help to lead a better understanding the pathogenesis of HCC and probe the feasibility of lncRNA-directed diagnosis and therapy for this deadly disease.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Sistema de Sinalização das MAP Quinases , MicroRNAs/antagonistas & inibidores , RNA Longo não Codificante/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Animais , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Células Hep G2 , Xenoenxertos , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , RNA Longo não Codificante/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Transdução de Sinais , Transfecção , Regulação para Cima
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