RESUMO
The mini-LED as the backlight of field sequential color LCD (FSC-LCD) enables high contrast, thin volume, and theoretically tripled light efficiency and resolution. However, color breakup (CBU) induced by a relative speed between an observer and the display severely limits the application of FSC-LCDs. Several driving algorithms have been proposed for CBU suppression, but their performance depends on image content. Moreover, their performance plateaus with increasing image segment number, preventing taking advantage of the massive segments introduced by mini-LEDs. Therefore, this study proposes an image content-adaptive driving algorithm for mini-LED FSC-LCDs. Deep learning-based image classification accurately determines the best FSC algorithm with the lowest CBU. In addition, the algorithm is heterogeneous that the image classification is independently performed in each segment, guaranteeing minimized CBU in all segments. We perform objective and subjective validation. Compared with the currently best algorithm, the proposed algorithm improves the performance in suppressing CBU by more than 20% using two evaluation metrics, supported by experiment-based subjective evaluation. Mini-LED FSC-LCDs driven by the proposed algorithm with outstanding CBU suppression can be ideal for display systems requiring high brightness and high resolution, such as head-up displays, virtual reality, and augmented reality displays.
RESUMO
OBJECTIVE: Studies have probed the function of microRNA (miR)-16-5p in the progression of atherosclerosis (AS), while the regulatory function of exosomal miR-16-5p from macrophage on AS remains largely unknown. This study commits to exploring the efficiency of exosomal miR-16-5p from macrophage on AS via modulating mothers against decapentaplegic homolog 7 (SMAD7). METHODS: Macrophages were cultured and transfected with miR-16-5p antagomir, then, the exosomes from macrophages were extracted. The AS mouse model was established, and miR-16-5p or SMAD7 expression in AS mice was detected. Thereafter, the effects of macrophage-derived exosomes, miR-16-5p or SMAD7 on serum inflammatory response, oxidative stress response, pathological changes and apoptosis in AS mice were observed by immunohistochemical and biochemical analysis. Finally, the binding relation between miR-16-5p and SMAD7 was examined. RESULTS: MiR-16-5p was elevated while SMAD7 was depleted in AS mice. Macrophage-derived exosomes aggravated AS progression via facilitating inflammatory response and oxidative stress, exacerbating pathological changes and increasing cell apoptosis in AS mice; while downregulation of miR-16-5p reversed the exacerbation of AS progression by macrophage-derived exosomes in AS mice. MiR-16-5p targeted SMAD7, and the down-regulated SMAD7 reversed the impacts of depleted miR-16-5p on AS progression. CONCLUSION: Exosomal miR-16-5p from macrophages aggravates AS progression via downregulating SMAD7 expression. This study provides novel therapeutic targets for AS treatment from the animal level.
Assuntos
Aterosclerose , Exossomos , Macrófagos , MicroRNAs , Proteína Smad7 , Animais , Aterosclerose/sangue , Aterosclerose/metabolismo , Aterosclerose/patologia , Regulação para Baixo , Exossomos/genética , Exossomos/metabolismo , Exossomos/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Smad7/genética , Proteína Smad7/metabolismoRESUMO
OBJECTIVES: Atherosclerosis (AS) remains a major contributor to death worldwide. This study sought to explore the role of Krüppel-like factor 7 (KLF7) in AS lesions via regulating glucose metabolic reprogramming (GMR) in macrophages. METHODS: AS mouse and cell models were established via high-fat-diet feeding and oxidized low-density lipoprotein (ox-LDL) induction. KLF7, histone deacetylase 4 (HDAC4), miR-148b-3p, and nuclear receptor corepressor 1 (NCOR1) expressions in aortic tissue and cells were detected via reverse transcription quantitative polymerase chain reaction or Western blotting. Parameters of AS lesions and mouse metabolism were detected via hematoxylin-eosin, oil red O, and Masson staining, assay kits, glucose tolerance test, and enzymatic analysis. Peritoneal macrophages of mice were isolated and cellular metabolism was detected via Seahorse metabolic flux analysis, assay kits, ELISA, and Western blotting. Bindings among KLF7, HDAC4, microRNA (miR)-148b-3p, and NCOR1 were testified via the dual-luciferase assay and chromatin immunoprecipitation assay. RESULTS: KLF7 was poorly expressed in AS mice and ox-LDL-induced RAW264.7 cells. KLF7 overexpression attenuated AS lesions and rescued metabolic abnormities in AS mice, and reduced glucose intake and GMR in ox-LDL-induced RAW264.7 cells. Mechanically, KLF7 bound to the HDAC4 promoter to activate HDAC4. HDAC4 reduced H3 and H4 acetylation levels in the miR-148b promoter to inhibit miR-148b-3p and promote NCOR1 transcription. HDAC4 downregulation abolished the protective role of KLF7 overexpression in AS mice and ox-LDL-induced RAW264.7 cells via the miR-148b-3p/NCOR1 axis. CONCLUSION: KLF7 bound to the HDAC4 promoter to activate HDAC4, inhibit miR-148b-3p via reducing acetylation level, and promote NCOR1 transcription, thereby limiting GMR in macrophages and alleviating AS lesions.
Assuntos
Aterosclerose , MicroRNAs , RNA Longo não Codificante , Animais , Camundongos , Apoptose , Aterosclerose/metabolismo , Proliferação de Células , Glucose/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Lipoproteínas LDL/metabolismo , Lipoproteínas LDL/farmacologia , Macrófagos/metabolismo , Macrófagos/patologia , MicroRNAs/genética , Correpressor 1 de Receptor Nuclear/genética , Correpressor 1 de Receptor Nuclear/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
The mechanisms that link hyperandrogenism and insulin (INS) resistance (HAIR) to the increased miscarriage rate in women with polycystic ovary syndrome (PCOS) remain elusive. Previous studies demonstrate that increased uterine and placental ferroptosis is associated with oxidative stress-induced fetal loss in a pre-clinical PCOS-like rat model. Here, we investigated the efficacy and molecular mechanism of action of the antioxidant N-acetylcysteine (NAC) in reversing gravid uterine and placental ferroptosis in pregnant rats exposed to 5α-dihydrotestosterone (DHT) and INS. Molecular and histological analyses showed that NAC attenuated DHT and INS-induced uterine ferroptosis, including dose-dependent increases in anti-ferroptosis gene content. Changes in other molecular factors after NAC treatment were also observed in the placenta exposed to DHT and INS, such as increased glutathione peroxidase 4 protein level. Furthermore, increased apoptosis-inducing factor mitochondria-associated 2 mRNA expression was seen in the placenta but not in the uterus. Additionally, NAC was not sufficient to rescue DHT + INS-induced mitochondria-morphological abnormalities in the uterus, whereas the same treatment partially reversed such abnormalities in the placenta. Finally, we demonstrated that NAC selectively normalized uterine leukemia inhibitory factor, osteopontin/secreted phosphoprotein 1, progesterone receptor, homeobox A11 mRNA expression and placental estrogen-related receptor beta and trophoblast-specific protein alpha mRNA expression. Collectively, our data provide insight into how NAC exerts beneficial effects on differentially attenuating gravid uterine and placental ferroptosis in a PCOS-like rat model with fetal loss. These results indicate that exogenous administration of NAC represents a potential therapeutic strategy in the treatment of HAIR-induced uterine and placental dysfunction.
Assuntos
Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Ferroptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Placenta/efeitos dos fármacos , Síndrome do Ovário Policístico/prevenção & controle , Útero/efeitos dos fármacos , Animais , Di-Hidrotestosterona , Modelos Animais de Doenças , Feminino , Glutationa/metabolismo , Resistência à Insulina , Ferro/metabolismo , Masculino , Malondialdeído/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Fosforilação Oxidativa , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Placenta/metabolismo , Placenta/ultraestrutura , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Gravidez , Ratos Sprague-Dawley , Transdução de Sinais , Útero/metabolismo , Útero/ultraestruturaRESUMO
Caspase recruitment domain 6 (CARD6) was initially implicated in the immune system and oncogenesis, which has also been emerged to play an important role in cardio-metabolic diseases. Nevertheless, the potential role of CARD6 on macrophage activation remains unknown. In the present study, we observed a decreased CARD6 expression in bone marrow derived macrophages (BMDMs) and mouse peritoneal macrophages (MPMs) isolated from ApoE deficiency mice and administrated with OX-LDL, which were tested by RT-PCR and western bolt analysis. Moreover, the immunofluorescence co-staining revealed that a weaker immunoreactivity of CARD6 was found and primary located in cytoplasm of macrophages induced by OX-LDL. Phenotypically, loss-of-function of CARD6 dramatically increased pro-inflammatory M1 macrophage but decreased resolving M2 macrophage markers expression. Additionally, CARD6 knockdown significantly promoted cholesterol uptake but attenuated cholesterol efflux, which lead to increased foam cell formation. Mechanistically, a downregulated AMP-activated protein kinase (AMPK) expression was required for the promoted effect of CARD6 knockdown on macrophage activation. Taken together, these results suggest that CARD6 protects against macrophage activation partially through activation of AMPK-dependent mechanism.
Assuntos
Proteínas Quinases Ativadas por AMP/imunologia , Proteínas Adaptadoras de Sinalização CARD/imunologia , Inflamação/imunologia , Ativação de Macrófagos , Proteínas Quinases Ativadas por AMP/genética , Animais , Proteínas Adaptadoras de Sinalização CARD/genética , Células Cultivadas , Regulação para Baixo , Técnicas de Silenciamento de Genes , Inflamação/genética , Lipoproteínas LDL/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , CamundongosRESUMO
We formulated a high birefringence, large dielectric anisotropy, UV stable, and low absorption loss nematic liquid crystal mixture, named UCF-15, for mid-wave infrared (MWIR) applications. To achieve fast response time, we fabricated a polymer network liquid crystal (PNLC) using UCF-15 as host. At 40°C operating temperature, our PNLC shows 2π phase change at λ = 4 µm, submillisecond response time, and over 98% transmittance in the 3.8 to 5.1 µm region. Potential applications of this PNLC phase modulator for high speed laser beam steering, adaptive optics, and optical tweezer are foreseeable.
RESUMO
To reduce the difficulty of acquiring and transmitting data in mining hoist fault diagnosis systems and to mitigate the low efficiency and unreasonable reasoning process problems, a fault diagnosis method for mine hoisting equipment based on the Internet of Things (IoT) is proposed in this study. The IoT requires three basic architectural layers: a perception layer, network layer, and application layer. In the perception layer, we designed a collaborative acquisition system based on the ZigBee short distance wireless communication technology for key components of the mine hoisting equipment. Real-time data acquisition was achieved, and a network layer was created by using long-distance wireless General Packet Radio Service (GPRS) transmission. The transmission and reception platforms for remote data transmission were able to transmit data in real time. A fault diagnosis reasoning method is proposed based on the improved Dezert-Smarandache Theory (DSmT) evidence theory, and fault diagnosis reasoning is performed. Based on interactive technology, a humanized and visualized fault diagnosis platform is created in the application layer. The method is then verified. A fault diagnosis test of the mine hoisting mechanism shows that the proposed diagnosis method obtains complete diagnostic data, and the diagnosis results have high accuracy and reliability.
RESUMO
OBJECTIVE: To investigate the effects of 18ß-glycyrrhetinic acid (GA) on the expression of eotaxin 1 (CCL11), aquaporin protein 1 (AQP1) and eosinophil (EOS) in nasal mucosa of allergic rhinitis (AR) rats. METHODS: Seventy six Wistar rats were randomly divided into 4 groups, normal control (NC) group, AR model (AR) group, loratadine (LOA) group and 18ß-GA group. All the mice in AR, LOA and 18ß-GA groups were sensitized intraperitoneally with OVA and AL(OH), from day 1-14, then induced by intranasal administration with OVA from day 14-21, while the mice in NC group were sensitized with saline. The mice in both LOA and 18ß-GA group were given LOA and 18ß-GA once a day respectively from the 21 d, while the mice in AR and NC groups were administrated with saline. At the end of 1 week, 2 weeks and 3 weeks, the behavioral changes of mice were observed and recorded, the level of CCL11 mRNA was measured by RT-QPCR, and AQP1 expression was investiaged by SP staing. EOS in nasal mucosa was studied with the methods of HE staining. RESULTS: Compared with NC group, AR group showed typical AR symptoms. With the treatments, AR symptom scores and the expression levels of CCL11, AQP1 and EOS in nasal mucosa were improved significantly (P<0. 05). When compared with AR group, the above statistics in LOA group were down-regulated evidently at different points in time (P<. 05). At the end of 1 week, the above detection results in 18ß-GA group were lower than those in AR group (P<0. 05). At the end of 2 weeks, those parameters approached to the levels of LOA and NC group significantly. CONCLUSION: 18ß-GA administration could down-regulate the expression levels of CCL11, AQP1 and EOS in nasal mucosa of allergic rhinitis rats and cast effects on inhibiting the progress of AR.
Assuntos
Aquaporina 1/metabolismo , Quimiocina CCL11/metabolismo , Eosinófilos/citologia , Ácido Glicirretínico/análogos & derivados , Mucosa Nasal/metabolismo , Rinite Alérgica/metabolismo , Animais , Ácido Glicirretínico/farmacologia , Mucosa Nasal/fisiopatologia , Ratos , Ratos Wistar , Rinite Alérgica/fisiopatologiaRESUMO
OBJECTIVE: The primary purpose of this study was to explore the safety of peripheral intravenous catheter (PIVC) replacement every 96 h compared to that of clinically indicated catheter removal. METHODS: A prospective, single-blind, randomized controlled trial was conducted. A random number table method was used. Six hundred patients treated with PIVC intravenous infusion in 10 nursing units of a hospital from September to October 2019 were selected. Sixty were collected from each nursing unit, including 30 in the clinically indicated replacement group and 30 in the routine replacement group. The incidence of phlebitis, catheter-related infection (CRI), occlusion, infiltration, and any form of infusion therapy failure were compared between the two groups. SPSS 23.0 software was used. RESULTS: The dwelling times of PIVC in the clinically indicated replacement group and routine replacement group were significantly different (hours) (83.62 ± 50.08, 69.75 ± 25.54, t = 3.021, p = 0.003). The incidence of any form of infusion therapy failure (RR = 4.448, 95% CI: 3.158-6.265, p < 0.001), phlebitis (RR = 2.416, 95% CI: 1.595-3.660, p < 0.001), occlusion (RR = 6.610, 95% CI: 3.062-14.268, p < 0.001), infiltration (RR = 2.607, 95% CI: 1.130-6.016, p = 0.020), accidental dislodgement (RR = 2.027, 95% CI: 1.868-2.200, p = 0.013), and pain at the insertion site (RR = 2.521, 95% CI: 1.742-3.649, p < 0.001) was higher in the clinically indicated replacement group than that in the routine replacement group. The overall survival curve of PIVC was drawn with Kaplan-Meier survival analysis. The median survival time of intravenous infusion was 59.58 h; the cumulative survival rates of 48 h, 72 h, and 96 h were 77.00%, 51.33%, and 20.33%, respectively. CONCLUSION: Replacement of PIVC every 96 h is safer than clinically indicated.
Assuntos
Cateterismo Periférico , Flebite , Cateterismo Periférico/efeitos adversos , Cateterismo Periférico/métodos , Catéteres/efeitos adversos , Humanos , Flebite/epidemiologia , Flebite/etiologia , Estudos Prospectivos , Método Simples-CegoRESUMO
BACKGROUND: The aim of this study was to observe the effect of Sacubitril/Valsartan on cardiac function and remodeling in patients with heart failure with reduced ejection fraction (HFrEF). METHODS: A total of 120 patients with HFrEF were selected and given standard heart failure treatment according to the 2017 ACC/AHA/HFSA guidelines. Regardless of whether patients had taken Angiotensin-Converting Enzyme Inhibitors/Angiotensin Receptor Blockers (ACEI/ARB) medications previously, after admission they were treated with the minimum effective dose of Sacubitril/Valsartan according to their blood pressure reading. Baseline clinical data were recorded and patients were followed up at 1, 3, 6, 9, and 12 months post discharge, during which time the dose of Sacubitril/Valsartan was gradually increased to the maximum tolerated dose (dose range 25-200 mg/twice daily). During follow-up, N-terminal pro-brain natriuretic peptide (NT-proBNP), left ventricular ejection fraction (LVEF), left ventricular end diastolic diameter (LVEDD), left ventricular end systolic diameter (LVESD), and left atrium diameter (LAD) were monitored; a 6-minute walking test and Kansas City Cardiomyopathy Questionnaire (KCCQ) scores were recorded; and adverse reactions were collected. RESULTS: Over the course of the 12-month follow-up, the plasma concentrations of NT-proBNP were significantly reduced compared with the baseline, and the longer the follow-up time, the lower the NT-proBNP levels were (P<0.05). Similarly, LVEDD, LVESD and LAD were significantly smaller at 12 months than at baseline, and the longer the follow-up time, the smaller the internal diameter was (P<0.05). The LVEF, 6-minute walking distance and KCCQ scores increased significantly from baseline (P<0.05), whereas eGFR and serum potassium levels showed no significant change compared with the baseline. CONCLUSIONS: Sacubitril/Valsartan demonstrated a remarkable ability to improve cardiac function and to control cardiac remodeling with a high degree of safety in patients with HFrEF.
Assuntos
Insuficiência Cardíaca , Assistência ao Convalescente , Aminobutiratos , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Compostos de Bifenilo , Combinação de Medicamentos , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Alta do Paciente , Volume Sistólico , Resultado do Tratamento , Valsartana , Função Ventricular Esquerda , Remodelação VentricularRESUMO
Benign paroxysmal positional vertigo is characterized by recurrence, which exposes patients to repeated vertigo attacks. Vitamin D deficiency has been found to be a risk factor in benign paroxysmal positional vertigo, although effect of its elimination on recurrence reduction remains unknown. To determine the effect of vitamin D supplementation in preventing recurrence of benign paroxysmal positional vertigo patients with vitamin D deficiency using a meta-analysis study. We searched and retrieved relevant articles from several databases, then used the Cochrane evaluation system or Methodological Index for Non-Randomized Studies (MINORS) to assess the quality of studies. We adopted risk-ratio (RR) with corresponding 95% confidence interval (CI) to determine effect sizes, and further performed statistical analyses under a randomized- or fixed-effects model. Seven studies, comprising 602 and 731 participants in the case and control group respectively, met our inclusion criteria, and were therefore included in the meta-analysis. Assessment based on Cochrane evaluation system or MINORS revealed that most of the studies had high quality. Moreover, the randomized- model revealed that the vitamin D supplementation group had a lower recurrence rate than the control group which did not accepted vitamin D supplementation (RR = 0.41, 95% CI = 0.26-0.65, p < 0.01). Overall, these findings indicate that vitamin D supplementation can significantly lower recurrence in benign paroxysmal positional vertigo and vitamin D deficiency.
Assuntos
Vertigem Posicional Paroxística Benigna , Deficiência de Vitamina D , Vertigem Posicional Paroxística Benigna/etiologia , Vertigem Posicional Paroxística Benigna/prevenção & controle , Suplementos Nutricionais , Humanos , Recidiva , Fatores de Risco , Vitamina D/uso terapêutico , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/tratamento farmacológicoRESUMO
As a highly dynamic tissue, the endometrium is periodically shed in response to the secretion of estrogen and progesterone. After menarche, the endometrium of healthy women proliferates and differentiates under the action of steroid hormones (e.g., 17ß-estradiol and progesterone) that are secreted by the ovaries to provide appropriate conditions for embryo implantation. Polycystic ovary syndrome (PCOS), a prevalent endocrine and metabolic disorder in reproductive-aged women, is usually associated with multiple cysts within the ovaries and excess levels of androgen and is characterized by hirsutism, acne, menstrual irregularity, infertility, and increased risk of insulin resistance. Multiple factors, such as anovulation, endocrine-metabolic abnormalities, and inflammation, can disrupt the endometrium in PCOS patients and can lead to endometrial hyperplasia, pregnancy complications, or even cancer. Despite many recent studies, the relationship between PCOS and abnormal endometrial function is still not fully understood. In this review, we investigate the correlation of PCOS patient endometrium with anovulation, hyperandrogenemia, insulin resistance, progesterone resistance, and inflammatory cytokines, aiming to provide a theoretical basis for the treatment of disorders caused by endometrial dysfunction in PCOS patients.
RESUMO
As a reproductive endocrine disease, polycystic ovary syndrome (PCOS) has influenced billions of women during childbearing age worldwide. Owing to its complex etiology and ambiguous pathogenesis, there is still not a specific method to cure it. Clinical treatments, such as hormone therapy and surgical treatment, have side effects. Therefore, it is essential and urgent to seek alternative treatment to solve these problems. The satisfactory efficacy of complementary and alternative medicine (CAM), such as traditional Chinese medicine (TCM), immunotherapy, medicinal foods, vitamin therapy, diet therapy, psychotherapy, spa, and oxygen therapy, in treating PCOS, has aroused an increasing number of medical workers' concern and gradually become the mainstream. This paper reviews the application of CAM in the treatment of PCOS, especially from the perspective of TCM. Meanwhile, the limitations of the literature about CAM in the treatment of PCOS are mentioned and analyzed as well.
RESUMO
BACKGROUND: The study of the development and evaluation of self-management intervention among patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) is lacking, especially in China. AIM: To examine the effects of a nurse-led individualized self-management program (NISMP) on health behaviors, control of cardiac risk factors, and health-related quality of life (HRQoL) among patients with AMI undergoing PCI. METHODS: The quasi-experimental design included a convenience sample of 112 participants recruited from a tertiary hospital in China. The participants were assigned to the control group (n = 56) or the intervention group (n = 56). The intervention group underwent the NISMP, which includes six group-based education sessions, a face-to-face individual consultation, and 12-month telephone follow-ups. Data were collected at baseline and at the end of the 12-month program using the Health Promotion Lifestyle Profile, the Risk Factors Assessment Form, and the Short Form 36-item Health Survey. RESULTS: The baseline sociodemographic and clinical characteristics of the two groups were comparable (p > 0.05). After the 12-month intervention, the health behaviors and HRQoL of the participants in the intervention group had significantly improved (p < 0.05 for both) compared to those of the control group. Compared to the control group, the participants in the intervention group also reported significantly better control of cardiac risk factors including smoking (χ2 = 4.709, p = 0.030), low-density lipoprotein (χ2 = 4.160, p = 0.041), body mass index (χ2 = 3.886, p = 0.049) and exercise (χ2 = 10.096, p = 0.001). CONCLUSION: The NISMP demonstrated positive effects on health behaviors, control of cardiac risk factors, and HRQoL among Chinese patients with AMI undergoing PCI.
Assuntos
Povo Asiático/psicologia , Comportamentos Relacionados com a Saúde , Infarto do Miocárdio/enfermagem , Papel do Profissional de Enfermagem , Educação de Pacientes como Assunto/métodos , Intervenção Coronária Percutânea/educação , Autogestão/educação , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/psicologia , Qualidade de Vida , Fatores de Risco , Autogestão/psicologia , Telefone , Resultado do TratamentoRESUMO
A submillisecond-response and light scattering-free polymer-network liquid crystal (PNLC) for infrared spatial light modulators is demonstrated. Our new liquid crystal host exhibits a higher birefringence, comparable dielectric anisotropy, and slightly lower visco-elastic constant than a commonly employed commercial material, HTG-135200. Moreover, the electro-optical performance of our PNLCs with different monomer concentrations, cell gaps, and liquid crystal (LC) hosts is compared and discussed from four aspects: operating voltage, hysteresis, relaxation time, and light scattering loss. The temperature effect on hysteresis is also analyzed. Potential applications of PNLCs for laser beam steering and spatial light modulators especially in the infrared region are foreseeable.
RESUMO
AIM: To study the modulation of extracellular pH on the voltage-gated potassium currents (I(Kv)) in isolated pulmonary artery smooth muscle cells (PASMCs). METHODS: I(Kv) was recorded using whole-cell patch clamp technique under the external solutions with different pH. The electrophysiological characteristics of I(Kv) were then analyzed. RESULTS: (1) As compared to the normoxic group, I(K), decreased under acidic condition. When the extracellular pH were 7.0, 6.5, 6.0, the peak currents at a potential of +60 mV were inhibited by 16.93% +/- 2.47% (P < 0.01), 33.03% +/- 2.13% (P < 0.01), 41.59% +/- 6.53% (P < 0.01) respectively, and the current-voltage relationship (I/V) curve shifted to the right. (2) When the extracellular pH was 7.0, 6.5, 6.0, the voltage-depended Gk-Em was shifted to the direction of positive and the activation was sped up. CONCLUSION: The results suggest that with the development of hypoxic pulmonary vasoconstriction (HPV), extracellular pH may take part in the modulation of Kv channels partly, then make the cell depolarized and decrease the Kv currents, this will lead to open the L-type calcium channel and contract the pulmonary artery smooth muscle. It may be one of the mechanisms that hypoxic leads to HPV and finally accelerate the development of HPV.