RESUMO
The contraction of heart cells is controlled by the intermolecular signaling between L-type Ca2+ channels (LCCs) and ryanodine receptors (RyRs), and the nanodistance between them depends on the interaction between junctophilin-2 (JPH2) in the sarcoplasmic reticulum (SR) and caveolin-3 (CAV3) in the transversal tubule (TT). In heart failure, decreased expression of JPH2 compromises LCC-RyR communication leading to deficient blood-pumping power. In the present study, we found that JPH2 and CAV3 transcription was concurrently regulated by serum response factor (SRF) and myocardin. In cardiomyocytes from torpid ground squirrels, compared with those from euthermic counterparts, myocardin expression was up-regulated, which boosted both JPH2 and CAV3 expression. Transmission electron microscopic imaging showed that the physical coupling between TTs and SRs was tightened during hibernation and after myocardin overexpression. Confocal Ca2+ imaging under the whole-cell patch clamp condition revealed that these changes enhanced the efficiency of LCC-RyR intermolecular signaling and fully compensated the adaptive down-regulation of LCCs, maintaining the power of heart contraction while avoiding the risk of calcium overload during hibernation. Our finding not only revealed an essential molecular mechanism underlying the survival of hibernating mammals, but also demonstrated a "reverse model of heart failure" at the molecular level, suggesting a strategy for treating heart diseases.
Assuntos
Sinalização do Cálcio , Hibernação , Miócitos Cardíacos/metabolismo , Animais , Caveolinas/genética , Caveolinas/metabolismo , Células Cultivadas , Acoplamento Excitação-Contração , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Nucleares/sangue , Proteínas Nucleares/metabolismo , Sciuridae , Transativadores/sangue , Transativadores/metabolismoRESUMO
RATIONALE: ßARs (ß-adrenergic receptors) are prototypical GPCRs (G protein-coupled receptors) that play a pivotal role in sympathetic regulation. In heart cells, ß1AR signaling mediates a global response, including both l-type Ca2+ channels in the sarcolemma/T tubules and RyRs (ryanodine receptors) in the SR (sarcoplasmic reticulum). In contrast, ß2AR mediates local signaling with little effect on the function of SR proteins. OBJECTIVE: To investigate the signaling relationship between ß1ARs and ß2ARs. METHOD AND RESULTS: Using whole-cell patch-clamp analyses combined with confocal Ca2+ imaging, we found that the activation of compartmentalized ß2AR signaling was able to convert the ß1AR signaling from global to local mode, preventing ß1ARs from phosphorylating RyRs that were only nanometers away from sarcolemma/T tubules. This offside compartmentalization was eliminated by selective inhibition of ß2AR, GRK2 (GPCR kinase-2), ßarr1 (ß-arrestin-1), and phosphodiesterase-4. A knockin rat model harboring mutations of the last 3 serine residues of the ß1AR C terminus, a component of the putative ßarr1 binding site and GRK2 phosphorylation site, eliminated the offside compartmentalization conferred by ß2AR activation. CONCLUSIONS: ß2AR stimulation compartmentalizes ß1AR signaling into nanoscale local domains in a phosphodiesterase-4-dependent manner by targeting the C terminus of ß1ARs. This finding reveals a fundamental negative feed-forward mechanism that serves to avoid the cytotoxicity of circulating catecholamine and to sharpen the transient ß1AR response of sympathetic excitation.
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Receptores Adrenérgicos beta 1/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Adrenérgicos/farmacologia , Animais , Células Cultivadas , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Masculino , Mutação , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Transgênicos , Receptores Adrenérgicos beta 1/química , Receptores Adrenérgicos beta 1/genética , Receptores Adrenérgicos beta 2/genética , Sarcolema/efeitos dos fármacos , Sarcolema/metabolismo , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Oncolytic viruses (OV) have shown excellent safety and efficacy in preclinical and clinical studies. Influenza A virus (IAV) is considered a promising oncolytic virus. In this report, we generated a recombinant influenza virus expressing an immune checkpoint blockade agent targeting CTLA4. Using reverse genetics, a recombinant influenza virus, termed rFlu-CTLA4, encoding the heavy chain of a CTLA4 antibody on the PB1 segment and the light chain of the CTLA4 antibody on the PA segment was produced. RFlu-CTLA4 could replicate to high titers, and antibodies were produced in the allantoic fluid of infected eggs. Furthermore, the selective cytotoxicity of the virus was higher in various hepatocellular carcinoma cancer cell lines than in the normal cell line L02 in vitro, as indicated by MTS assays. More importantly, in a subcutaneous H22 mouse hepatocarcinoma model, intratumoral injections of rFlu-CTLA4 inhibited the growth of treated tumors and increased the overall survival of mice compared with injections of the PR8 virus. Taken together, these results warrant further exploration of this novel recombinant influenza virus for its potential use as a single or combination agent for cancer immunotherapy.
Assuntos
Antígeno CTLA-4/imunologia , Imunoterapia/métodos , Vírus da Influenza A/imunologia , Neoplasias/terapia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/imunologia , Animais , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Backgroud/Aims: The biological function of cardiac troponin I-interacting kinase (TNNI3K), a cardiac-specific functional kinase, is largely unknown. We investigated the effect of human TNNI3K (hTNNI3K) on the differentiation of mouse embryonic stem cells (mESCs) into cardiomyocytes. METHODS: First, the time-space expression of endogenous Tnni3k was detected by real-time polymerase chain reaction (PCR) and western blotting at 16 different time-points over a period of 28 days. Further, action potentials and calcium current with/without 5 µM nifedipine were measured by patch clamp for mESC-derived cardiomyocytes. HTNNI3K and mouse-derived siRNA were transfected into mESC using lentivirus vector to induce hTNNI3K overexpression and knock-down, respectively. RESULTS: The number of troponin-T (cTnT) positive cells was greater in the group with TNNI3K overexpression as compared to that in control group, while less such cells were detected in the mTnni3k knock-down group as evaluated on flow cytometry (FCM) and ImageXpress Micro system. After upregulation of connexin43, cardiac troponin-I (Ctni), Ctni, Gata4 were detected in mESCs with TNNI3K overexpression; however, overexpression of α-Actinin and Mlc2v was not detected. Interestingly, Ctnt, connexin40 and connexin45, the markers of ventricular, atrial, and pacemaker cells, respectively, were detected in by real-time PCR in TNNI3K overexpression group. CONCLUSION: our study indicated that TNNI3K overexpression promoted mESC differentiating into beating cardiomyocytes and induced up-regulating expression of cTnT by PKCε signal pathway, which suggested a modulation of TNNI3K activity as a potential therapeutic approach for ischemic cardiac disease.
Assuntos
MAP Quinase Quinase Quinases/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Cálcio/metabolismo , Diferenciação Celular , Conexina 43/metabolismo , Humanos , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/genética , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Células-Tronco Embrionárias Murinas/citologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/ultraestrutura , Técnicas de Patch-Clamp , Proteína Quinase C-épsilon/metabolismo , Proteínas Serina-Treonina Quinases , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Troponina I/metabolismo , Troponina T/metabolismoRESUMO
Acute respiratory distress syndrome (ARDS) is a complex syndrome disorder with high mortality rate. Camel milk (CM) contains antiinflammatory and antioxidant properties and protects against numerous diseases. This study aimed to demonstrate the function of CM in lipopolysaccharide (LPS)-induced ARDS in rats. Camel milk reduced the lung wet:dry weight ratio and significantly reduced LPS-induced increases in neutrophil infiltration, interstitial and intra-alveolar edema, thickness of the alveolar wall, and lung injury scores of lung tissues. It also had antiinflammatory and antioxidant effects on LPS-induced ARDS. After LPS stimulation, the levels of proinflammatory cytokines (tumor necrosis factor-α, IL-10, and IL-1ß) in serum and oxidative stress markers (malondialdehyde, myeloperoxidase, and total antioxidant capacity) in lung tissue were notably attenuated by CM. Camel milk also downregulated mitogen-activated protein kinase signaling pathways. Given these results, CM is a potential complementary food for ARDS treatment.
Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Leite/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Estresse Oxidativo/efeitos dos fármacos , Síndrome do Desconforto Respiratório/genética , Animais , Camelus , Regulação para Baixo , Lipopolissacarídeos/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ratos , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/fisiopatologia , Transdução de SinaisRESUMO
Age-related osteoporosis is characterized by an imbalance between osteogenic and adipogenic differentiation in bone mesenchymal stem cells (BMSCs). Forkhead box O 3 (FoxO3) transcription factor is involved in lifespan and cell differentiation. In this study, we explore whether FoxO3 regulates age-related bone loss and marrow fat accumulation. The expression levels of FoxO3 in BMSCs during aging were detected in vivo and in vitro. To explore the role of FoxO3 in osteogenic and adipogenic differentiation, primary BMSCs were isolated from young and aged mice. FoxO3 expression was modulated by adenoviral vector transfection. The role of FoxO3 in bone-fat balance was evaluated by alizarin red S staining, oil red O staining, quantitative reverse transcription-polymerase chain reaction, Western blot, and histological analysis. Age-related bone loss and fat deposit are associated with downregulation of FoxO3. Overexpression of FoxO3 alleviated age-related bone loss and marrow fat accumulation in aged mice. Mechanistically, FoxO3 reduced adipogenesis and enhanced osteogenesis of BMSCs via downregulation of PPAR-γ and Notch signaling, respectively. In conclusion, FoxO3 is an essential factor controlling the fate of BMSCs and is a potential target for the prevention of age-related osteoporosis.
Assuntos
Adipogenia , Envelhecimento , Proteína Forkhead Box O3 , Células-Tronco Mesenquimais , Osteogênese , Animais , Proteína Forkhead Box O3/metabolismo , Proteína Forkhead Box O3/genética , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Envelhecimento/genética , Envelhecimento/metabolismo , Osteogênese/genética , Camundongos , Adipogenia/genética , Diferenciação Celular/genética , Camundongos Endogâmicos C57BL , Osteoporose/metabolismo , Osteoporose/patologia , Osteoporose/genética , Osso e Ossos/metabolismo , Transdução de Sinais , PPAR gama/metabolismo , PPAR gama/genética , Masculino , Células Cultivadas , Receptores Notch/metabolismo , Receptores Notch/genéticaRESUMO
Although the pathogenesis of osteoarthritis (OA) is unclear, inflammatory cytokines are related to its occurrence. However, few studies focused on the therapeutic strategies of regulating joint homeostasis by simultaneously remodeling the anti-inflammatory and immunomodulatory microenvironments. Fibroblast growth factor 18 (FGF18) is the only disease-modifying OA drug (DMOAD) with a potent ability and high efficiency in maintaining the phenotype of chondrocytes within cell culture models. However, its potential role in the immune microenvironment remains unknown. Besides, information on an optimal carrier, whose interface and chondral-biomimetic microenvironment mimic the native articular tissue, is still lacking, which substantially limits the clinical efficacy of FGF18. Herein, to simulate the cartilage matrix, chondroitin sulfate (ChS)-based nanoparticles (NPs) are integrated into poly(D, L-lactide)-poly(ethylene glycol)-poly(D, L-lactide) (PLEL) hydrogels to develop a bionic thermosensitive sustainable delivery system. Electrostatically self-assembled ChS and ε-poly-l-lysine (EPL) NPs are prepared for the bioencapsulation of FGF18. This bionic delivery system suppressed the inflammatory response in interleukin-1ß (IL-1ß)-mediated chondrocytes, promoted macrophage M2 polarization, and inhibited M1 polarization, thereby ameliorating cartilage degeneration and synovitis in OA. Thus, the ChS-based hydrogel system offers a potential strategy to regulate the chondrocyte-macrophage crosstalk, thus re-establishing the anti-inflammatory and immunomodulatory microenvironment for OA therapy.
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Condrócitos , Sulfatos de Condroitina , Homeostase , Nanopartículas , Osteoartrite , Osteoartrite/patologia , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Animais , Condrócitos/metabolismo , Condrócitos/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Nanopartículas/química , Sulfatos de Condroitina/química , Fatores de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/farmacologia , Camundongos , Hidrogéis/química , Biônica , Células RAW 264.7 , Masculino , Sistemas de Liberação de Medicamentos/métodos , Humanos , Ratos , Ratos Sprague-Dawley , Cartilagem Articular/patologia , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismoRESUMO
The differentiation of pluripotent stem cells (PSCs) into diverse functional cell types provides a promising solution to support drug discovery, disease modeling, and regenerative medicine. However, functional cell differentiation is currently limited by the substantial line-to-line and batch-to-batch variabilities, which severely impede the progress of scientific research and the manufacturing of cell products. For instance, PSC-to-cardiomyocyte (CM) differentiation is vulnerable to inappropriate doses of CHIR99021 (CHIR) that are applied in the initial stage of mesoderm differentiation. Here, by harnessing live-cell bright-field imaging and machine learning (ML), we realize real-time cell recognition in the entire differentiation process, e.g., CMs, cardiac progenitor cells (CPCs), PSC clones, and even misdifferentiated cells. This enables non-invasive prediction of differentiation efficiency, purification of ML-recognized CMs and CPCs for reducing cell contamination, early assessment of the CHIR dose for correcting the misdifferentiation trajectory, and evaluation of initial PSC colonies for controlling the start point of differentiation, all of which provide a more invulnerable differentiation method with resistance to variability. Moreover, with the established ML models as a readout for the chemical screen, we identify a CDK8 inhibitor that can further improve the cell resistance to the overdose of CHIR. Together, this study indicates that artificial intelligence is able to guide and iteratively optimize PSC differentiation to achieve consistently high efficiency across cell lines and batches, providing a better understanding and rational modulation of the differentiation process for functional cell manufacturing in biomedical applications.
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CACNA1E is a gene encoding the ion-conducting α1 subunit of R-type voltage-dependent calcium channels, whose roles in tumorigenesis remain to be determined. We previously showed that CACNA1E was significantly mutated in patients with non-small cell lung cancer (NSCLC) who were long-term exposed to household air pollution, with a mutation rate of 19% (15 of 79 cases). Here we showed that CACNA1E was also mutated in 207 (12.8%) of the 1616 patients with NSCLC in The Cancer Genome Atlas (TCGA) datasets. At mRNA and protein levels, CACNA1E was elevated in tumor tissues compared to counterpart non-tumoral lung tissues in NSCLCs of the public datasets and our settings, and its expression level was inversely associated with clinical outcome of the patients. Overexpression of wild type (WT) or A275S or R249G mutant CACNA1E transcripts promoted NSCLC cell proliferation with activation of epidermal growth factor receptor (EGFR) signaling pathway, whereas knockdown of this gene exerted inhibitory effects on NSCLC cells in vitro and in vivo. CACNA1E increased current density and Ca2+ entrance, whereas calcium channel blockers inhibited NSCLC cell proliferation. These data indicate that CACNA1E is required for NSCLC cell proliferation, and blockade of this oncoprotein may have therapeutic potentials for this deadly disease.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Cálcio/metabolismo , Canais de Cálcio Tipo R , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Transporte de Cátions , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Mutação/genéticaRESUMO
FTIR spectra of fourth-generation space bred radix isatidis and FTIR spectra of radix isatidis in a ground group were determined on the whole. Comparative analysis was conducted on main constituents (components) to accumulate data for comprehensively understanding and thoroughly studying the inherent property, and to explore a method of evaluating the quality of space bred radix isatidis. The results showed that slight difference existed in the positions and shapes of the absorption peaks in FTIR spectra of samples between the two groups. The intensities of main absorption peaks of radix isatidis in the space group were strengthened to various degrees compared with those in the ground group. The absorption peaks were markedly enhanced at wave numbers of 1 047, 1 630 and 1 412 cm(-1), indicating that the contents of polysaccharides, sterides, triterpenes and flavanoids, particularly polysaccharides with anti-viral efficacy, increased to different extents. The absorption peak intensity of space radix isatidis at the wave number of 1 745 cm(-1) was weakened compared with that of radix isatidis in the ground group, suggesting the reduction of glycosides and organic acids. It is concluded that the contents of a plurality of active components of radix isatidis in the space group are elevated. New radix isatidis varieties with high contents of diverse active components can be harvested by spaceflight mutation breeding.
Assuntos
Medicamentos de Ervas Chinesas/análise , Isatis/química , Espectroscopia de Infravermelho com Transformada de Fourier , Antivirais , Voo EspacialRESUMO
We study the seasonal variations of δ13C ratios in aerosol fine particulate matter (PM2.5) using 91 PM2.5 samples collected from Xinxiang, China, during the summer and winter in 2017. Mass concentrations of total carbon (TC), water soluble ions, and stable carbon isotope ratios (δ13C) were determined. The mean concentrations of TC in the summer and winter were 11.78 µg·m-3 and 26.6 µg·m-3, respectively. The δ13C ratio in the summer ranged from -27.70 to -25.22. The daily δ13C ratio fluctuated in the first half of the summer months (mean -26.96), whereas the δ13C ratio in the second half of the summer was relatively stable (mean -25.69). The number of fires in the study area during the first half of the summer was quite different to the number during the second half of the summer, meanwhile, there was a positive correlation between the Knss+ concentration and the TC mass concentration (R2=0.62, P<0.01). This indicates that biomass burning most likely contributed to variations in δ13C. During the winter there was a significant negative correlation between winter RH and the TC/PM2.5 mass ratio (R2=0.68, P<0.01), which suggests that SOA growth was dominant in the early stage of haze development, whereas the pollution period was dominated by SIA components. The ratio of δ13C ranged from -26.72 to -23.49, and there was a difference between the variation of the δ13C ratio in haze episode (when it was mainly enriched in the development stage) to that in the stage dominated by depletion.
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BACKGROUND: Gastric cancer is the second most common malignant tumor in China, ranking third among all malignant tumor mortality rates. Hyperthermic intraperitoneal chemotherapy (HIPEC) has been shown to increase significantly the effectiveness of intraperitoneal chemotherapeutic drugs, prolong the action time of these drugs on intraperitoneal tumor cells, and enhance their diffusion in tumor tissues. HIPEC may be one of the best choices for the eradication of residual cancer cells in the abdominal cavity. AIM: The aim of this study was to study the role of preventive HIPEC after radical gastrectomy. METHODS: A prospective analysis was performed with patients with cT4N0-3M0 gastric cancer to compare the effects of postoperative prophylactic HIPEC plus intravenous chemotherapy with those of routine adjuvant chemotherapy. Patients' medical records were analyzed, and differences in the peritoneal recurrence rate, disease-free survival time, and total survival time between groups were examined. RESULTS: The first site of tumor recurrence was the peritoneum in 11 cases in the conventional adjuvant chemotherapy group and in 2 cases in the HIPEC group (P = 0.020). The 1-year and 3-year disease-free survival rates were 91.9% and 60.4%, respectively, in the conventional adjuvant chemotherapy group and 92.1% and 63.0%, respectively, in the HIPEC group. The 1-year and 3-year overall survival rates were 95.2% and 66.3%, respectively, in the conventional adjuvant chemotherapy group and 96.1% and 68.6%, respectively, in the HIPEC group. No significant difference in postoperative or chemotherapy complications was observed between groups. CONCLUSION: In patients with cT4N0-3M0 gastric cancer, prophylactic HIPEC after radical tumor surgery is beneficial to reduce peritoneal tumor recurrence and prolong survival.
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BACKGROUND: Gastric cancer (GC) is a heavy burden in China. Nutritional support for GC patients is closely related to postoperative rehabilitation. However, the role of early oral feeding after laparoscopic radical total gastrectomy in GC patients is unclear and high-quality research evidence is scarce. AIM: To prospectively explore the safety, feasibility and short-term clinical outcomes of early oral feeding after laparoscopic radical total gastrectomy for GC patients. METHODS: This study was a prospective cohort study conducted between January 2018 and December 2019 based in a high-volume tertiary hospital in China. A total of 206 patients who underwent laparoscopic radical total gastrectomy for GC were enrolled. Of which, 105 patients were given early oral feeding (EOF group) after surgery, and the other 101 patients were given the traditional feeding strategy (control group) after surgery. Perioperative clinical data were recorded and analyzed. The primary endpoints were gastrointestinal function recovery time and postoperative complications, and the secondary endpoints were postoperative nutritional status, length of hospital stay and expenses, etc. RESULTS: Compared with the control group, patients in the EOF group had a significantly shorter postoperative first exhaust time (2.48 ± 1.17 d vs 3.37 ± 1.42 d, P = 0.001) and first defecation time (3.83 ± 2.41 d vs 5.32 ± 2.70 d, P = 0. 004). In addition, the EOF group had a significant shorter postoperative hospitalization duration (5.85 ± 1.53 d vs 7.71 ± 1.56 d, P < 0.001) and lower postoperative hospitalization expenses (16.60 ± 5.10 K¥ vs 21.00 ± 7.50 K¥, P = 0.014). On the 5th day after surgery, serum prealbumin level (214.52 ± 22.47 mg/L vs 204.17 ± 20.62 mg/L, P = 0.018), serum gastrin level (246.30 ± 57.10 ng/L vs 223.60 ± 55.70 ng/L, P = 0.001) and serum motilin level (424.60 ± 68.30 ng/L vs 409.30 ± 61.70 ng/L, P = 0.002) were higher in the EOF group. However, there was no significant difference in the incidence of total postoperative complications between the two groups (P = 0.507). CONCLUSION: Early oral feeding after laparoscopic radical total gastrectomy can promote the recovery of gastrointestinal function, improve postoperative nutritional status, reduce length of hospital stay and expenses while not increasing the incidence of related complications, which indicates its safety, feasibility and potential benefits for gastric cancer patients.
Assuntos
Laparoscopia , Neoplasias Gástricas , China , Gastrectomia/efeitos adversos , Humanos , Laparoscopia/efeitos adversos , Tempo de Internação , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Neoplasias Gástricas/cirurgia , Resultado do TratamentoRESUMO
AIMS: ß-adrenergic receptors (ßARs) play pivotal roles in regulating cardiac excitation-contraction (E-C) coupling. Global signalling of ß1ARs up-regulates both the influx of Ca2+ through sarcolemmal L-type Ca2+ channels (LCCs) and the release of Ca2+ from the sarcoplasmic reticulum (SR) through the ryanodine receptors (RyRs). However, we recently found that ß2AR stimulation meditates 'offside compartmentalization', confining ß1AR signalling into subsarcolemmal nanodomains without reaching SR proteins. In the present study, we aim to investigate the new question, whether and how compartmentalized ß1AR signalling regulates cardiac E-C coupling. METHODS AND RESULTS: By combining confocal Ca2+ imaging and patch-clamp techniques, we investigated the effects of compartmentalized ßAR signalling on E-C coupling at both cellular and molecular levels. We found that simultaneous activation of ß2 and ß1ARs, in contrast to global signalling of ß1ARs, modulated neither the amplitude and spatiotemporal properties of Ca2+ sparks nor the kinetics of the RyR response to LCC Ca2+ sparklets. Nevertheless, by up-regulating LCC current, compartmentalized ß1AR signalling synchronized RyR Ca2+ release and increased the functional reserve (stability margin) of E-C coupling. In circumstances of briefer excitation durations or lower RyR responsivity, compartmentalized ßAR signalling, by increasing the intensity of Ca2+ triggers, helped stabilize the performance of E-C coupling and enhanced the Ca2+ transient amplitude in failing heart cells. CONCLUSION: Given that compartmentalized ßAR signalling can be induced by stress-associated levels of catecholamines, our results revealed an important, yet unappreciated, heart regulation mechanism that is autoadaptive to varied stress conditions.
Assuntos
Canais de Cálcio Tipo L/metabolismo , Sinalização do Cálcio , Cardiomegalia/metabolismo , Acoplamento Excitação-Contração , Contração Miocárdica , Miócitos Cardíacos/metabolismo , Receptores Adrenérgicos beta 1/metabolismo , Potenciais de Ação , Agonistas Adrenérgicos/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Cardiomegalia/fisiopatologia , Simulação por Computador , Modelos Animais de Doenças , Acoplamento Excitação-Contração/efeitos dos fármacos , Cinética , Masculino , Microscopia Confocal , Modelos Cardiovasculares , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta 1/efeitos dos fármacos , Receptores Adrenérgicos beta 2/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismoRESUMO
Endoscopic submucosal dissection (ESD) is a minimally invasive alternative to esophagectomy for early esophageal squamous cell carcinoma (EESCC). The aim of this study was to compare the efficacy and safety of ESD and esophagectomy in EESCC with different depth of invasion. The data of EESCC patients who received ESD or esophagectomy between Jan 2011 to Dec 2018 at our center were retrospectively analyzed. Overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS), and procedure-related variables were compared between ESD and esophagectomy patients. 222 EESCC patients underwent ESD, while 184 underwent esophagectomy. No significant differences were found between the two groups in OS (P=0.417), DSS (P=0.423), and RFS (P=0.726). Procedure duration, post-procedure hospital stay, and hospitalization cost were all lower in ESD patients. Oncologic outcomes were similar between the two groups in propensity score-matched analysis. The R0 resection rate was comparable between ESD and esophagectomy groups in the T1a-M1/M2 and M3/SM1 EESCC subgroups; no significant differences were found in OS, DSS and RFS. In the SM2/SM3 EESCC subgroup, although the prognosis of the two treatment groups was similar, the R0 resection rate was significantly lower in ESD patients than in esophagectomy patients. Thus, we concluded ESD could be a first-line treatment for T1a-M1/M2 and M3/SM1 EESCC as oncologic outcome is comparable to that achieved with esophagectomy with minimal invasion, lower cost and lower incidence of serious adverse events. However, in SM2/SM3 EESCC patients, esophagectomy may be preferable.
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OBJECTIVE: To study the effects of prenatal cold stress on the behavior and mood of offspring in pregnant rats. METHODS: Six SPF-class Wister pregnant rats were randomly divided into normal temperature control group and cold stress group with 3 rats in each group. The pregnant female rats in the normal temperature control group were kept in the environment of (22 ±2)â, and the pregnant female rats in the cold stress group were placed in the artificial intelligence climate chamber at(4 ±0.1)â for 7 days before the birth, and the young rats were divided into normal temperature after the young rats were born. After the young rats were born, they were divided into normal temperature control group of male rats (MR, 22), normal temperature control group of mother rats (FR, 15), cold stress group of male rats (MC, 15), and cold stress group of female rats (FC, 15) .In the fourth generation of the offspring, the open field experiment and the elevated cross maze test were carried out. RESULTS: In the open field experiment, there was no significant difference in spontaneous activity and exploration behavior between the normal temperature control group and the cold stress group (Pï¼0.05). In the elevated plus maze experiment, the retention time of the open arms, the number of open arms and the distance of the male and female rats in the cold stress group were significantly higher than those in the normal temperature control group (Pï¼0.05). CONCLUSION: Prenatal maternal cold stress has no significant effect on spontaneous activity, exploration behavior and activity level of offspring, but the offspring have obvious abnormal behaviors with reduced anxiety behavior.
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Ansiedade , Comportamento Animal , Resposta ao Choque Frio , Comportamento Exploratório , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Masculino , Aprendizagem em Labirinto , Gravidez , Distribuição Aleatória , Ratos , Estresse PsicológicoRESUMO
MicroRNAs (miRNAs) play important roles in maintaining normal heart function. Abnormal expression of miR-331 has been observed in the hearts of patients with atrial fibrillation and Marfan syndrome. However, whether miR-331 regulates cardiac function under physiological and pathological conditions still remains unknown. In the present study, we investigated the function and underlying mechanisms of miR-331 in a pressure overload-induced heart failure model and miR-331 transgenic rat model. First, we found that the expression of miR-331-3p exhibited a 1.7-fold increase in hypertrophy compared with that in the sham group (Pâ¯<â¯0.01), yet the expression of miR-331-5p remained unchanged. Furthermore, overexpression of miR-331 in cardiomyocytes and defective excitation-contraction (E-C) coupling efficiency were observed. Luciferase assays showed that miR-331-3p suppressed JPH2 expression by binding to the coding region of JPH2 mRNA. Finally, in the miR-331 transgenic rat model, JPH2 expression was suppressed at both the mRNA and protein levels in vivo, which resulted in impairment of both the E-C coupling efficiency of cardiomyocytes and systolic function of the heart. This finding mechanistically linked miR-331 to JPH2 downregulation and suggested an important role for the abnormal expression of miR-331 leading to the dysfunction of E-C coupling in heart failure.
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During 11-18 September 2014, the size-resolved aerosol Cloud Condensation Nuclei (CCN) activity and mixing state were measured using Cloud Condensation Nuclei Counter (CCNC), Aerosol Particle Mass (APM) and Scanning Mobility Particle Sizer (SMPS). The results showed that aerosols mainly existed as an internal mixture. For 76, 111, 138 and 181 nm particles, black carbon (BC) accounted for 5.4%, 10%, l0.7% and 6.7% of the particle mass, but as high as 51%, 57%, 70% and 59% of the particle number concentrations, respectively, suggesting that BC was a type of important condensation nuclei in the atmosphere and made significant contributions to particle numbers. The occasionally observed external mixtures were mainly present in 111 and 138 nm particles. The critical supersaturation was 0.25%, 0.13%, 0.06% and 0.015% for 76, 111, 138 and 181 nm particles, respectively. Precipitation and haze had significant effects on the particle CCN activity. The hygroscopicity parameter K was 0.37, 0.29 and 0.39 in rainy, clear and hazy days, respectively. Particle density and CCN activity were impacted by chemical compositions. Compared with clear days, higher contents of inorganic salts and lower contents of organics were found on hazy days, accompanied by lower particle density and higher CCN activity.
Assuntos
Aerossóis/análise , Atmosfera/análise , Monitoramento Ambiental , China , Cidades , Tamanho da Partícula , Fuligem/análise , MolhabilidadeRESUMO
In January 2013 large-scale, continuous and severe haze occurred in Nanjing. Three-wavelength photoacoustic soot spectrometer (PASS-3) was used for real-time, online and situ measurements of aerosol absorption and scattering coefficients in the northern suburb of Nanjing during January 2013. The results indicated that the average aerosol absorption and scattering coefficients were (83.20 ± 35.24) Mm⻹ and (670.16 ± 136.44) Mm⻹ during haze days, which were 3.85 and 3.45 times higher than those on clean days, respectively. The diurnal variation of absorption and scattering coefficients showed a bimodal distribution. The mean single scattering albedo and scattering Angstrom exponent were (0.89 ± 0.04) and (1.30 ± 0.27) respectively, indicating the predominance of scattering fine particles during haze days in Nanjing. Aerosols could be significantly removed by precipitation. The absorption and scattering coefficients showed negative correlations with surface wind speed, and the single scattering albedo and Angstrom exponent showed positive correlations with wind speed. Aerosol scattering coefficient was highest under southeasterly wind, whereas the absorption coefficient was highest under the southwesterly wind. In the three haze pollution events, Haze 1 and Haze 2 were mainly affected by long-range transportation of pollutants. Haze 1 was mainly affected by aging air mass from north Nanjing, Haze 2 was mainly affected by biomass burning air mass from southwest Nanjing, while Haze 3 was mainly caused by the high sulfate.
Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Biomassa , China , Tamanho da Partícula , Fuligem/análise , Sulfatos/análise , VentoRESUMO
Atmospheric particulate samples of PM2.5 were collected from the northern suburb of Nanjing in December, 2014, and a LC-MS method was optimized for the determination of aromatic acids in PM2.5; The concentrations of major water-soluble ions, organic carbon and elemental carbon were also determined. The quantification results showed that the average total concentration of five aromatic acids we have determined was (50.01±16.05) ng·m-3, and the average concentrations of terephthalic acid, phthalic acid, trimellitic acid, 4-methylphthalic acid and iso-phthalic acid were (34.54±12.79)ã(8.14±3.34)ã(2.27±1.39)ã(1.68±0.77) and (1.08±0.43) ng·m-3, respectively. The different source apportionments of atmospheric particulate were analyzed by principal component analysis/absolute principal component scores (PCA/APCS) receptor model. The results of source apportionment showed that the main sources of Phthalic acid, Trimellitic acid and 4-methylphthalic acid were mainly secondary transformation, and primary emissions such as vehicle exhaust contributed less to Trimellitic acid; Secondary transformation and biomass burning made the most significant contributions to iso-Phthalic acid and vehicle exhaust contributed less; The sources of Terephthalic acid were primary emissions such as biomass burning and vehicle exhaust.