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A key barrier to the development of vaccines that induce broadly neutralizing antibodies (bnAbs) against human immunodeficiency virus (HIV) and other viruses of high antigenic diversity is the design of priming immunogens that induce rare bnAb-precursor B cells. The high neutralization breadth of the HIV bnAb 10E8 makes elicitation of 10E8-class bnAbs desirable; however, the recessed epitope within gp41 makes envelope trimers poor priming immunogens and requires that 10E8-class bnAbs possess a long heavy chain complementarity determining region 3 (HCDR3) with a specific binding motif. We developed germline-targeting epitope scaffolds with affinity for 10E8-class precursors and engineered nanoparticles for multivalent display. Scaffolds exhibited epitope structural mimicry and bound bnAb-precursor human naive B cells in ex vivo screens, protein nanoparticles induced bnAb-precursor responses in stringent mouse models and rhesus macaques, and mRNA-encoded nanoparticles triggered similar responses in mice. Thus, germline-targeting epitope scaffold nanoparticles can elicit rare bnAb-precursor B cells with predefined binding specificities and HCDR3 features.
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Vacinas contra a AIDS , Anticorpos Neutralizantes , Anticorpos Anti-HIV , Proteína gp41 do Envelope de HIV , Infecções por HIV , HIV-1 , Macaca mulatta , Animais , Humanos , Proteína gp41 do Envelope de HIV/imunologia , Anticorpos Anti-HIV/imunologia , Camundongos , Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/imunologia , HIV-1/imunologia , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Vacinação , Anticorpos Amplamente Neutralizantes/imunologia , Linfócitos B/imunologia , Nanopartículas/química , Feminino , Regiões Determinantes de Complementaridade/imunologia , Epitopos/imunologiaRESUMO
Tumor-induced host wasting and mortality are general phenomena across species. Many groups have previously demonstrated endocrinal impacts of malignant tumors on host wasting in rodents and Drosophila. Whether and how environmental factors and host immune response contribute to tumor-associated host wasting and survival, however, are largely unknown. Here, we report that flies bearing malignant yki3SA-gut tumors exhibited the exponential increase of commensal bacteria, which were mostly acquired from the environment, and systemic IMD-NF-κB activation due to suppression of a gut antibacterial amidase PGRP-SC2. Either gut microbial elimination or specific IMD-NF-κB blockade in the renal-like Malpighian tubules potently improved mortality of yki3SA-tumor-bearing flies in a manner independent of host wasting. We further indicate that renal IMD-NF-κB activation caused uric acid (UA) overload to reduce survival of tumor-bearing flies. Therefore, our results uncover a fundamental mechanism whereby gut commensal dysbiosis, renal immune activation, and UA imbalance potentiate tumor-associated host death.
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NF-kappa B , Neoplasias , Animais , Proteínas de Transporte , Drosophila , Homeostase , NF-kappa B/metabolismo , Ácido ÚricoRESUMO
High night temperature stress is one of the main environmental factors affecting rice yield and quality. More and more evidence shows that microRNA (miRNA) plays an important role in various abiotic stresses. However, the molecular network of miRNA regulation on rice tolerance to high night temperatures remains unclear. Here, small RNA, transcriptome and degradome sequencing were integrated to identify differentially expressed miRNAs, genes, and key miRNA-target gene pairs in rice heat-sensitive and heat-tolerant lines at the filling stage suffering from high night temperature stress. It was discovered that there were notable differences in the relative expression of 102 miRNAs between the two rice lines under stress. Meanwhile, 5263 and 5405 mRNAs were differentially expressed in the heat-sensitive line and heat-tolerant line, and functional enrichment analysis revealed that these genes were involved in heat-related processes and pathways. The miRNAs-mRNAs target relationship was further verified by degradome sequencing. Eventually, 49 miRNAs-222 mRNAs target pairs with reverse expression patterns showed significant relative expression changes between the heat-tolerant and the heat-sensitive line, being suggested to be responsible for the heat tolerance difference of these two rice lines. Functional analysis of these 222 mRNA transcripts showed that high night temperature-responsive miRNAs targeted these mRNAs involved in many heat-related biological processes, such as transcription regulation, chloroplast regulation, mitochondrion regulation, protein folding, hormone regulation and redox process. This study identified possible miRNA-mRNA regulation relationships in response to high night temperature stress in rice and potentially contributed to heat resistance breeding of rice in the future.
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Regulação da Expressão Gênica de Plantas , MicroRNAs , Oryza , Oryza/genética , Oryza/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Estresse Fisiológico/genética , Temperatura Alta , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , Transcriptoma/genética , Perfilação da Expressão Gênica , Resposta ao Choque Térmico/genéticaRESUMO
Transition metal selenides, boasting remarkable specific capacity, have emerged as a promising electrode material. However, the substantial volume fluctuations during sodium ion insertion and extraction result in inadequate cyclic stability and rate performance, impeding their practical utility. Here, we synthesized N-doped carbon three-dimensional (3D) interconnected networks encapsulating (NiCo)3Se4 nanoparticles, denoted as ((NiCo)3Se4/N-C), exhibiting a bead-like structure and carbon confinement through electrospinning and subsequent thermal treatment. The N-doped carbon 3D interconnected networks possess high porosity and ample volume buffering capacity, enhance conductivity, shorten ion diffusion paths, and mitigate mechanical stress induced by volume changes during cycling. The uniformly distributed (NiCo)3Se4 nanoparticles, featuring a stable structure, demonstrate rapid electrochemical kinetics and numerous available active sites. The distinctive structure and composition of the optimized (NiCo)3Se4/N-C material showcase a high specific capacity (656.2 mAh g-1 at 0.1 A g-1) and an outstanding rate capability. A kinetic analysis confirms that (NiCo)3Se4/N-C stimulates the pseudocapacitive Na+ storage mechanism with capacitance contributing up to 89.2% of the total capacity. This unique structure design and doping approach provide new insights into the design of electrode materials for high-performance batteries.
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Practical applications of lithium-sulfur (Li-S) batteries have been hindered by sluggish reaction kinetics and severe capacity decay during charge-discharge cycling due to the notorious shuttle effect of polysulfide and the unfavored deposition and dissolution of Li2 S. Herein, to address these issues, a double-defect engineering strategy is developed for preparing Co-doped FeP catalyst containing P vacancies on MXene, which effectively improves the bidirectional redox of Li2 S. Mechanism analysis indicates that P vacancy accelerates Li2 S nucleation via increased unsaturated sites, and Co doping generates local electric field to reduce the reaction energy barrier and accelerate Li2 S dissolution. MXene provides highly conductive channels for electron transport, and effectively captures polysulfide. The double-defect catalyst enables an impressive reversible specific capacity of 1297.9 mAh g-1 at 0.2 C, and excellent rate capability of 726.5 mAh g-1 at 4 C. Remarkably, it demonstrates excellent cycling stability with capacity retention of 533.3 mAh g-1 after 500 cycles at 2 C. The results can unlock the double-defect engineering of vacancy induction and heteroatomic doping towards practical Li-S batteries.
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BACKGROUND AND OBJECTIVE: Emotional stress substantially increases the risk of ischemic cardiovascular diseases. Previous study indicates that sympathetic outflow is increased under emotional stress. We aim to investigate the role of increased sympathetic outflow induced by emotional stress in myocardial ischemia-reperfusion (I/R) injury, and explore the underlying mechanisms. METHODS AND RESULTS: We used Designer Receptors Exclusively Activated by Designer Drugs technique to activate the ventromedial hypothalamus (VMH), a critical emotion-related nucleus. The results revealed that emotional stress stimulated by VMH activation increased sympathetic outflow, enhanced blood pressure, aggravated myocardial I/R injury, and exacerbated infarct size. The RNA-seq and molecular detection demonstrated that toll-like receptor 7 (TLR7), myeloid differentiation factor 88 (MyD88), interferon regulatory factor 5 (IRF5), and downstream inflammatory markers in cardiomyocytes were significantly upregulated. Emotional stress-induced sympathetic outflow further exacerbated the disorder of the TLR7/MyD88/IRF5 inflammatory signaling pathway. While inhibition of the signaling pathway partially alleviated myocardial I/R injury aggravated by emotional stress-induced sympathetic outflow. CONCLUSION: Increased sympathetic outflow induced by emotional stress activates TLR7/MyD88/IRF5 signaling pathway, ultimately aggravating I/R injury.
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Traumatismo por Reperfusão Miocárdica , Angústia Psicológica , Traumatismo por Reperfusão , Humanos , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 7 Toll-Like , Receptor 4 Toll-Like/metabolismo , Transdução de Sinais , Fatores Reguladores de Interferon/metabolismo , Traumatismo por Reperfusão/metabolismoRESUMO
BACKGROUND: The advantages of multimodal digitally transformed mobile health management for patients diagnosed with mild to moderate hypertension are not yet established. OBJECTIVE: We aim to evaluate the therapeutic benefits of a novel WeChat-based multimodal digital transforming management model in mobile health blood pressure (BP) management. METHODS: This randomized controlled clinical trial included 175 individuals with new-onset mild to moderate hypertension who were admitted to our center between September and October 2022. The patients were randomly assigned to either the multimodal intervention group (n=88) or the usual care group (n=87). The primary composite outcome was home and office BP differences after 6 months. The major secondary outcomes were 6-month quality-of-life scores, including the self-rating anxiety scale, self-rating depression scale, and Pittsburgh Sleep Quality Index. RESULTS: The mean home BP decreased from 151.74 (SD 8.02)/94.22 (SD 9.32) to 126.19 (SD 8.45)/82.28 (SD 9.26) mm Hg in the multimodal intervention group and from 150.78 (SD 7.87)/91.53 (SD 9.78) to 133.48 (SD 10.86)/84.45 (SD 9.19) mm Hg in the usual care group, with a mean difference in systolic blood pressure and diastolic blood pressure of -8.25 mm Hg (95% CI -11.71 to -4.78 mm Hg; P<.001) and -4.85 mm Hg (95% CI -8.41 to -1.30 mm Hg; P=.008), respectively. The mean office BP decreased from 153.64 (SD 8.39)/93.56 (SD 8.45) to 127.81 (SD 8.04)/ 82.16 (SD 8.06) mm Hg in the multimodal intervention group and from 151.48 (SD 7.14)/(91.31 (SD 9.61) to 134.92 (SD 10.11)/85.09 (SD 8.26) mm Hg in the usual care group, with a mean difference in systolic blood pressure and diastolic blood pressure of -9.27 mm Hg (95% CI -12.62 to -5.91 mm Hg; P<.001) and -5.18 mm Hg (95% CI -8.47 to -1.89 mm Hg; P=.002), respectively. From baseline to 6 months, home BP control <140/90 mm Hg was achieved in 64 (72.7%) patients in the multimodal intervention group and 46 (52.9%) patients in the usual care group (P=.007). Meanwhile, home BP control <130/80 mm Hg was achieved in 32 (36.4%) patients in the multimodal intervention group and 16 (18.4%) patients in the usual care group (P=.008). After 6 months, there were significant differences in the quality-of-life total and graded scores, including self-rating anxiety scale scores (P=.04), self-rating depression scale scores (P=.03), and Pittsburgh Sleep Quality Index scores (P<.001), in the multimodal intervention group compared with the usual care group. CONCLUSIONS: The WeChat-based multimodal intervention model improved the BP control rates and lowered the BP levels more than the usual care approach. The multimodal digital transforming management model for hypertension represents an emerging medical practice that utilizes the individual's various risk factor profiles for primary care and personalized therapy decision-making in patients with hypertension. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2200063550; https://www.chictr.org.cn/showproj.html?proj=175816.
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Saúde Digital , Hipertensão , Aplicativos Móveis , Humanos , Povo Asiático , Pressão Sanguínea , Hospitalização , Hipertensão/terapia , Qualidade de VidaRESUMO
Many nutrition delivery systems (NDSs) have been developed for the encapsulation, protection, and delivery of bioactive compounds, such as ß-carotene. Most of those systems were prepared in solution, which is inconvenient for transportation and storage in the food industry. In the present work, we constructed an environmentally friendly dry NDS based on defatted soybean particles (DSPs) by milling a ß-carotene-DSP mixture. The loading efficiency of the NDS reached 89.0%, and the cumulative release rate decreased from 15.1% (free ß-carotene) to 6.0% within 8 h. The stability of ß-carotene in the dry NDS was found to have increased in a thermogravimetric analysis. Stored for 14 days at 55 °C or under UV irradiation, the retaining rates of ß-carotene in the NDS increased to 50.7% and 63.6%, respectively, while they were 24.2% and 54.6% for the free samples. The bioavailability of ß-carotene was improved by the NDS too. The apparent permeability coefficient of the NDS reached 1.37 × 10-6 cm/s, which is 12 times that of free ß-carotene (0.11 × 10-6 cm/s). Besides being environmentally friendly, the dry NDS can facilitate carriage, transportation, or storage in the food industry, and similar to other NDSs, it improves the stability and bioavailability of nutrients.
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Glycine max , beta Caroteno , EmulsõesRESUMO
Food allergies are a global food safety problem. Peanut allergies are common due, in part, to their popular utilization in the food industry. Peanut allergy is typically an immunoglobulin E-mediated reaction, and peanuts contain 17 allergens belonging to different families in peanut. In this review, we first introduce the mechanisms and management of peanut allergy, followed by the basic structures of associated allergens. Subsequently, we summarize methods of epitope localization for peanut allergens. These methods can be instrumental in speeding up the discovery of allergenicity-dependent structures. Many attempts have been made to decrease the allergenicity of peanuts. The structures of hypoallergens, which are manufactured during processing, were analyzed to strengthen the desensitization process and allergen immunotherapy. The identification of conformational epitopes is the bottleneck in both peanut and food allergies. Further, the identification and modification of such epitopes will lead to improved strategies for managing and preventing peanut allergy. Combining traditional wet chemistry research with structure simulation studies will help in the epitopes' localization.
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Arachis , Hipersensibilidade a Amendoim , Humanos , Arachis/química , Hipersensibilidade a Amendoim/prevenção & controle , Alérgenos , Indústria Alimentícia , EpitoposRESUMO
BACKGROUND: Children and older adults with coronavirus disease 2019 (COVID-19) display a distinct spectrum of disease severity yet the risk factors aren't well understood. We sought to examine the expression pattern of angiotensin-converting enzyme 2 (ACE2), the cell-entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the role of lung progenitor cells in children and older patients. METHODS: We retrospectively analyzed clinical features in a cohort of 299 patients with COVID-19. The expression and distribution of ACE2 and lung progenitor cells were systematically examined using a combination of public single-cell RNA-seq data sets, lung biopsies, and ex vivo infection of lung tissues with SARS-CoV-2 pseudovirus in children and older adults. We also followed up patients who had recovered from COVID-19. RESULTS: Compared with children, older patients (>50 years.) were more likely to develop into serious pneumonia with reduced lymphocytes and aberrant inflammatory response (P = .001). The expression level of ACE2 and lung progenitor cell markers were generally decreased in older patients. Notably, ACE2 positive cells were mainly distributed in the alveolar region, including SFTPC positive cells, but rarely in airway regions in the older adults (P < .01). The follow-up of discharged patients revealed a prolonged recovery from pneumonia in the older (P < .025). CONCLUSIONS: Compared to children, ACE2 positive cells are generally decreased in older adults and mainly presented in the lower pulmonary tract. The lung progenitor cells are also decreased. These risk factors may impact disease severity and recovery from pneumonia caused by SARS-Cov-2 infection in older patients.
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Enzima de Conversão de Angiotensina 2/genética , COVID-19 , Células-Tronco , Idoso , Criança , Humanos , Pulmão/citologia , Pessoa de Meia-Idade , RNA-Seq , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Low-level vagus nerve stimulation (LL-VNS) has been demonstrated to protect myocardium against acute ischemia/reperfusion (I/R) injury. However, the underlying mechanism of this protective effect remains unknown. OBJECTIVE: This study aimed to test the hypothesis that LL-VNS exerts cardioprotective effect on acute I/R injury in canines via antioxidative stress and antiapoptosis reactions. METHOD: Thirty anesthetized mongrel dogs were randomly divided into three groups: I/R group (N = 12, the left anterior descending coronary artery was occluded for 1 hour following by 1 hour reperfusion), LL-VNS group (N = 9, I/R plus LL-VNS), and sham group (N = 9, sham surgery without LL-VNS). The voltage threshold was set at 80% of the voltage required to slow the sinus rate. Infarct size was assessed with Evans Blue and triphenyltetrazolium chloride. Activity assays, TUNEL staining, and western blotting were performed to determine markers of oxidative stress and apoptosis. RESULTS: LL-VNS significantly decreased the incidence of ventricular arrhythmias, increased vagal tone, as confirmed by heart rate viability, and reduced infarct size compared with the I/R group. This improvement was associated with a reduction in myocardial neutrophil infiltration, the inhibition of oxidative stress, and the suppression in cardiomyocyte apoptosis. In contrast, the lack of LL-VNS in the I/R group induced the opposite effect compared with the sham group. CONCLUSION: LL-VNS exerts protective effects on myocardial I/R injury. Its potential mechanisms involve the suppression of oxidative stress and cellular apoptosis.
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Apoptose , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Miocárdio/patologia , Estresse Oxidativo , Estimulação do Nervo Vago/métodos , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Cães , Frequência Cardíaca , Malondialdeído/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Tempo , Proteína X Associada a bcl-2/metabolismoRESUMO
BACKGROUND: Hyperactivity of the cardiac sympathetic nervous system may underlie the pathogenesis of inappropriate sinus tachycardia (IST). Studies have proven that cervical vagal stimulation could inhibit stellate ganglion neural activity. SUBJECTS: To investigate whether noninvasive vagal nerve stimulation (NVNS) could inhibit sympathetically induced sinus node acceleration by reducing right stellate ganglion (RSG) neural activity. METHODS: Sixteen anesthetized dogs were randomly divided into NVNS group (with NVNS, n = 8) and control group (with sham NVNS, n = 8). NVNS was delivered to the vagus nerve innervating at the right tragus with a voltage of 80% below the threshold, the minimal voltage to slow the sinus rate or atrioventricular conduction. The maximal sinus rate accelerations induced by high-frequency stimulation (HFS) of RSG and RSG neural activity were measured at baseline and 3 hours after NVNS. At the end, SK2, c-fos, and NGF protein expression in RSG were examined in both groups. RESULTS: Compared to baseline, the maximal sinus node acceleration induced by RSG stimulation and the RSG neural activity were both significantly attenuated after 3 hours of NVNS (P < 0.05 for both). However, these indices did not change significantly in the control group (P > 0.05). SK2 expression in RSG was significantly higher and c-fos and NGF expressions were significantly lower in the NVNS group than those in the control group (P < 0.05). CONCLUSION: Noninvasive vagal nerve stimulation may suppress RSG activity possibly by modulating SK2, c-fos, and NGF expressions in RSG, thus inhibiting sympathetically induced sinus node acceleration.
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Frequência Cardíaca , Nó Sinoatrial/inervação , Gânglio Estrelado/fisiopatologia , Taquicardia Sinusal/terapia , Estimulação do Nervo Vago/métodos , Animais , Modelos Animais de Doenças , Cães , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Baixa/genética , Canais de Potássio Ativados por Cálcio de Condutância Baixa/metabolismo , Gânglio Estrelado/metabolismo , Taquicardia Sinusal/etiologia , Taquicardia Sinusal/genética , Taquicardia Sinusal/metabolismo , Taquicardia Sinusal/fisiopatologia , Fatores de TempoRESUMO
Vagus nerve stimulation improves left ventricular (LV) remodeling by downregulation of matrix metalloproteinase 9 (MMP-9) and transforming growth factor ß1 (TGF-ß1). Our previous study found that low-level transcutaneous electrical stimulation of the auricular branch of the vagus nerve (LL-TS) could be substituted for vagus nerve stimulation to reverse cardiac remodeling. So, we hypothesize that LL-TS could ameliorate LV remodeling by regulation of MMP-9 and TGF-ß1 after myocardial infarction (MI). Twenty-two beagle dogs were randomly divided into a control group (MI was induced by permanent ligation of the left coronary artery, n = 8), an LL-TS group (MI with long-term intermittent LL-TS, n = 8), and a normal group (sham ligation without stimulation, n = 6). At the end of 6 weeks follow-up, LL-TS significantly reduced LV end-systolic and end-diastolic dimensions, improved ejection fraction and ratio of early (E) to late (A) peak mitral inflow velocity. LL-TS attenuated interstitial fibrosis and collagen degradation in the noninfarcted myocardium compared with the control group. Elevated level of MMP-9 and TGF-ß1 in LV tissue and peripheral plasma were diminished in the LL-TS treated dogs. LL-TS improves cardiac function and prevents cardiac remodeling in the late stages after MI by downregulation of MMP-9 and TGF-ß1 expression.
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Metaloproteinase 9 da Matriz/metabolismo , Infarto do Miocárdio , Fator de Crescimento Transformador beta1/metabolismo , Estimulação do Nervo Vago/métodos , Disfunção Ventricular Esquerda , Remodelação Ventricular/fisiologia , Animais , Modelos Animais de Doenças , Cães , Regulação para Baixo , Ventrículos do Coração/inervação , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Volume Sistólico , Estimulação Elétrica Nervosa Transcutânea/métodos , Resultado do Tratamento , Nervo Vago , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/metabolismo , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
BACKGROUND: We have previously shown that right-sided low-level tragus nerve stimulation (LL-TS) is an effective approach for the treatment of atrial fibrillation (AF) induced by rapid atrial pacing (RAP) and acts by preventing the loss of atrial connexins (Cxs). Whether a left-sided approach would achieve the same effect remains unknown. OBJECTIVE: We hypothesized that left-sided LL-TS would inhibit AF by preserving atrial Cxs as effectively as right-sided LL-TS. METHODS: Bilateral thoracotomies allowed the attachment of multielectrode catheters to the pulmonary vein and non-pulmonary vein sites in 32 anaesthetized beagles. The dogs were randomly divided into 3 groups: RAP group (9 hours of RAP at the left appendage, n = 10), LL-TS group (9-hour RAP plus LL-TS, n = 12), and control group (sham RAP without LL-TS, n = 10). Alligator clips were clipped on the tragus of the left ear for electrical stimulation (20 Hz, 1 millisecond square waves). A voltage of stimulation setting at 80% below the threshold that slowed the sinus rate was defined as LL-TS. Electrophysiological parameters were measured at baseline and 9 hours after pacing. Connexin proteins from atrial tissues were measured at the end of the protocol. RESULTS: RAP induced a significant reduction in the effective refractory period and an increase in AF inducibility (P < 0.05). However, left-sided LL-TS reversed the effective refractory period reduction induced by RAP and the increase in AF inducibility. It also shortened the AF duration and prolonged the AF cycle length, which are associated with Cx40 and Cx43 upregulation (P < 0.05). CONCLUSIONS: We propose that left-sided LL-TS exerts its anti-AF effects through upregulation of Cxs as effectively as right-sided LL-TS, suggesting that LL-TS for AF suppression is not unique to the right tragus nerve.
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Fibrilação Atrial/metabolismo , Fibrilação Atrial/prevenção & controle , Junções Comunicantes/metabolismo , Regulação para Cima/fisiologia , Estimulação do Nervo Vago/métodos , Animais , Cães , Meato Acústico Externo/fisiologia , Átrios do Coração/metabolismo , MasculinoRESUMO
OBJECTIVE: This study was designed to demonstrate that spinal cord stimulation (SCS) could suppress high-frequency stimulation (HFS)-induced focal atrial fibrillation (AF) at atrial and pulmonary vein (PV) sites by inhibiting atrial ganglionated plexus (GP) activity. METHODS: Multielectrode catheters were attached to atria and all PV sites. SCS was performed at the T1-T5 spinal region for 1 hour. At the baseline state and the end of 1 hour of SCS, 40 milliseconds of HFS was delivered 2 milliseconds after atrial pacing to determine the AF threshold at each site. One electrode was attached to the superior left GP so that HFS to this site induced sinus rate slowing. Microelectrodes inserted into the anterior right GP recorded neural firing. RESULTS: SCS induced a significant increase in AF threshold at all sites (all P < 0.05). The sinus rate slowing response induced by superior left GP stimulation was blunted by SCS (17% ± 3.6% vs. 39% ± 3.8%, P < 0.05). The frequency (32 ± 4 vs. 87 ± 6 impulses per minute, P < 0.05) and amplitude (0.16 ± 0.02 vs. 0.42 ± 0.04 mv, P < 0.05) of the neural activity recorded from the anterior right GP were markedly inhibited by SCS. CONCLUSIONS: SCS may prevent episodic AF caused by rapid PV and non-PV firing through modulating GP activity.
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Fibrilação Atrial/terapia , Gânglios Autônomos/metabolismo , Átrios do Coração/fisiopatologia , Estimulação da Medula Espinal/métodos , Animais , Fibrilação Atrial/fisiopatologia , Modelos Animais de Doenças , Cães , Masculino , Veias Pulmonares/metabolismoRESUMO
: Electrical carotid baroreceptor stimulation (CBS) has shown therapeutic potential for resistant hypertension and heart failure by resetting autonomic nervous system, but the impacts on arrhythmias remains unclear. This study evaluated the effects of CBS on ventricular electrophysiological properties in normal dog heart and arrhythmias after acute myocardial infarction (AMI). In the acute protocol, anesthetized open chest dogs were exposed to 1 hour left anterior descending coronary occlusion as AMI model. Dogs were received either sham treatment (Control group, n = 8) or CBS (CBS group, n = 8), started 1 hour before AMI. CBS resulted in pronounced prolongation of ventricular effective refractory period and reduction of the maximum action potential duration restitution slope (from 0.85 ± 0.15 in the baseline state to 0.67 ± 0.09 at the end of 1 hour, P < 0.05) before AMI. Number of premature ventricular contractions (277 ± 168 in the Control group vs. 103 ± 84 in the CBS group, P < 0.05) and episodes of ventricular tachycardia/ventricular fibrillation (7 ± 3 in the Control group vs. 3 ± 2 in the CBS group, P < 0.05) was decreased compared with the control group during AMI. CBS buffered low-frequency/high-frequency ratio raise during AMI. Ischemic size was not affected by CBS. CBS may have a beneficial impact on ventricular arrhythmias induced by AMI through modulation of autonomic tone.
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Terapia por Estimulação Elétrica/métodos , Infarto do Miocárdio/terapia , Taquicardia Ventricular/prevenção & controle , Fibrilação Ventricular/prevenção & controle , Potenciais de Ação/fisiologia , Animais , Sistema Nervoso Autônomo/metabolismo , Modelos Animais de Doenças , Cães , Masculino , Infarto do Miocárdio/complicações , Infarto do Miocárdio/fisiopatologia , Pressorreceptores/metabolismo , Taquicardia Ventricular/etiologia , Fibrilação Ventricular/etiologia , Complexos Ventriculares Prematuros/etiologia , Complexos Ventriculares Prematuros/prevenção & controleRESUMO
OBJECTIVE: To investigate whether selectively stimulating ß1-adrenergic receptor could inhibit high mobility group box 1 protein and attenuate myocardial ischemia/reperfusion(I/R) injury in rats. METHODS: Eighty healthy male Sprague-Dawley (SD) rats were randomly divided into seven groups: (1) Sham operated group (SO); (2) Ischemia/reperfusion (I/R) group; (3) Dobutamine1 (5 µg×kg⻹ · min⻹) + I/R group; (4) Dobutamine2 (10 µg·kg⻹ × min⻹) + I/R group; (5) LY294002 (0.3 mg/kg) + Dobutamine2 + I/R group; (6) SB203580 (1 mg/kg) + Dobutamine2 + I/R group; (7) ZnPPIX (10 mg/kg) + Dobutamine2+I/R group. Rats were pretreated by saline, dobutamine, LY294002, SB203580 and ZnPPIX, respectively, then underwent myocardial I/R. Myocardial I/R injury and oxidative stress were assessed, and myocardial HO-1, NF-κB and HMGB1 expressions were measured by Western blot analysis. RESULTS: Dobutamine significantly reduced the myocardial infarct size (P < 0.05), myocardial enzymes (LDH and CK) (P < 0.05) and proinfiammation cytokines (TNF-α and IL-6), reduced oxidative stress (MDA and SOD) in a dose-dependent manner (all P < 0.05). Meanwhile, dobutamine significantly and dose-dependently mediated the induction of HO-1 (P < 0.05), the expression of NF-κB (P < 0.05) and HMGB1 (P < 0.05). However, all the effects could be significantly reversed by co-treatment with LY294002, SB203580 and ZnPPIX (all P < 0.05). CONCLUSIONS: Current study demonstrates that selectively stimulating ß1-adrenergic receptor by dobutasmine could reduce rat myocardial I/R injury in vivo through promoting the induction of HO-1 and inhibiting HMGB1 release.
Assuntos
Proteína HMGB1/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Animais , Cromonas , Dobutamina , Proteína HMGB1/efeitos dos fármacos , Imidazóis , Interleucina-6 , Masculino , Morfolinas , Infarto do Miocárdio , Isquemia Miocárdica , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miocárdio , NF-kappa B , Estresse Oxidativo , Piridinas , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos , Traumatismo por Reperfusão , Superóxido Dismutase , Fator de Necrose Tumoral alfaRESUMO
Karst groundwater plays an irreplaceable role in the formation and development of urban areas, and land-use and land-cover change (LUCC) and the input of pollutants during the urbanization process would pose potential environmental risks to underground rivers. We analysed the relationship between urbanization processes and underground river hydrochemistry over nearly 35 years in Guiyang city, southwest of China, it was found that concentrations of various cations and anions, as well as total dissolved solids (TDS), gradually increased with the urbanization process, with significant fluctuations during the rapid urbanization periods. The Hydrochemical Facies Evolution Diagram (HFED) clearly showed the influence of urbanization on the hydrochemistry of the underground rivers. The ion ratios of γMg2+/γCa2+-γHCO3-, γNa+/γCl-, Ca2+/Mg2+-Ca2+ or Mg2+/Σ cations, HCO3-/SO42--HCO3- or SO42-/Σ anions revealed two distinct phases in the hydrochemical evolution of the underground river system, highly consistent with the urbanization process. Before the rapid urbanization, acid deposition and agricultural activities affected the hydrochemistry, with HCO3-Ca·Mg and HCO3·SO4-Ca·Mg as the dominant types controlled by limestone and dolomite dissolution in water-rock interactions. As acid deposition diminished, the input of SO42- from urban sewage compensated for the reduced impact, but the increased impermeable surfaces reduced the infiltration of atmospheric precipitation, leading to a reduced dissolution of dolomite minerals in water-rock interactions, resulting in a decrease in Mg2+ and a change in the hydrochemical type. The hydrochemical type evolved from a single HCO3·SO4-Ca·Mg type and HCO3-Ca·Mg type to multiple types, such as HCO3·Cl-Ca, HCO3·SO4-Ca, HCO3-Ca, and HCO3·SO4-Ca·Mg, and was highly unstable. With changes in land use, the proportions of various cations and anions in the hydrochemistry changed, especially NH4+, NO3-, SO42-, Na+, and Cl-, which were more sensitive to human activities. This study indicated the impact of urbanization on the hydrochemistry of the underground river system, with the input of SO42- from human activities and the increase in paved surfaces due to urbanization collectively altering the hydrochemical types of the underground river system. The rapid response of karst underground river system hydrochemistry indicates a potential impact on groundwater system by urbanization that should not be ignored.
Assuntos
Monitoramento Ambiental , Água Subterrânea , Rios , Urbanização , Poluentes Químicos da Água , Rios/química , China , Água Subterrânea/química , Água Subterrânea/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodosRESUMO
Metagenomic next-generation sequencing (mNGS) is an unbiased and rapid method for detecting pathogens. This study enrolled 145 suspected severe pneumonia patients who were admitted to the Affiliated Hospital of Jining Medical University. This study primarily aimed to determine the diagnostic performance of mNGS and conventional microbiological tests (CMTs) using bronchoalveolar lavage fluid samples for detecting pathogens. Our findings indicated that mNGS performed significantly higher sensitivity (97.54% vs 28.68%, P < 0.001), coincidence (90.34% vs 35.17%, P < 0.001), and negative predictive value (80.00% vs 13.21%, P < 0.001) but performed lower specificity than CMTs (52.17% vs 87.5%, P < 0.001). Streptococcus pneumoniae as the most common bacterial pathogen had the largest proportion (22.90%, 30/131) in this study. In addition to bacteria, fungi, and virus, mNGS can detect a variety of atypical pathogens such as Mycobacterium tuberculosis and non-tuberculous. Mixed infections were common in patients with severe pneumonia, and bacterial-fungal-viral-atypical pathogens were the most complicated infection. After adjustments of antibiotics based on mNGS and CMTs, the clinical manifestation improved in 139 (95.86%, 139/145) patients. Our data demonstrated that mNGS had significant advantage in diagnosing respiratory tract infections, especially atypical pathogens and fungal infections. Pathogens were detected timely and comprehensively, contributing to the adjustments of antibiotic treatments timely and accurately, improving patient prognosis and decreasing mortality potentially.IMPORTANCEMetagenomic next-generation sequencing using bronchoalveolar lavage fluid can provide more comprehensive and accurate pathogens for respiratory tract infections, especially when considering the previous usage of empirical antibiotics before admission or complicated clinical presentation. This technology is expected to play an important role in the precise application of antimicrobial drugs in the future.