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1.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983848

RESUMO

Tiny water drops produced from bubble bursting play a critical role in forming clouds, scattering sunlight, and transporting pathogens from water to the air. Bubbles burst by nucleating a hole at their cap foot and may produce jets or film drops. The latter originate from the fragmentation of liquid ligaments formed by the centripetal destabilization of the opening hole rim. They constitute a major fraction of the aerosols produced from bubbles with cap radius of curvature (R) > ∼0.4 × capillary length (a). However, our present understanding of the corresponding mechanisms does not explain the production of most submicron film drops, which represent the main number fraction of sea spray aerosols. In this study, we report observations showing that bursting bubbles with R < ∼0.4a are actually mainly responsible for submicron film drop production, through a mechanism involving the flapping shear instability of the cap with the outer environment. With this proposed pathway, the complex relations between bubble size and number of drops produced per bubble can be better explained, providing a fundamental framework for understanding the production flux of aerosols and the transfer of substances mediated by bubble bursting through the air-water interface and the sensitivity of the process to the nature of the environment.

2.
Small ; : e2401755, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698572

RESUMO

Infrared and radar detectors posed substantial challenges to weapon equipment and personnel due to their continuous surveillance and reconnaissance capabilities. Traditional single-band stealth devices are insufficient for dual-band detection in both infrared and microwave bands. To overcome this limitation, a gradient-structured MXene/reduced graphene oxide (rGO) composite aerogel (GMXrGA) is fabricated through a two-step bidirectional freeze casting process, followed by freeze-drying and thermal annealing. GMXrGA exhibits a distinct three-layered structure, with each layer playing a crucial role in microwave absorption. This deliberate design amplifies both the efficiency of microwave absorption and the material's effectiveness in dynamic infrared camouflage. GMXrGA displays an ultralow density of 5.2 mg∙cm-3 and demonstrates exceptional resistance to compression, enduring 200 cycles at a maximum strain of 80%. Moreover, it shows superior microwave absorption performance, with a minimum reflection loss (RLmin) of -60.1 dB at a broad effective absorption bandwidth (EAB) of 14.1 GHz (3.9-18.0 GHz). Additionally, the aerogel exhibits low thermal conductivity (≈26 mW∙m-1∙K-1) and displays dynamic infrared camouflage capabilities within the temperature range of 50-120 °C, achieving rapid concealment within 30 s. Consequently, they hold great potential for diverse applications, including intelligent buildings, wearable electronics, and weapon equipment.

3.
J Environ Sci (China) ; 138: 88-101, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135436

RESUMO

The reaction of carbonyl-to-imine/hemiaminal conversion in the atmospheric aqueous phase is a critical pathway to produce the light-absorbing N-containing secondary organic compounds (SOC). The formation mechanism of these compounds has been wildly investigated in bulk solutions with a low ionic strength. However, the ionic strength in the aqueous phase of the polluted atmosphere may be higher. It is still unclear whether and to what extent the inorganic ions can affect the SOC formation. Here we prepared the bulk solution with certain ionic strength, in which glyoxal and ammonium were mixed to mimic the aqueous-phase reaction. Molecular characterization by High-resolution Mass Spectrometry was performed to identify the N-containing products, and the light absorption of the mixtures was measured by ultraviolet-visible spectroscopy. Thirty-nine N-containing compounds were identified and divided into four categories (N-heterocyclic chromophores, high-molecular-weight compounds with N-heterocycle, aliphatic imines/hemiaminals, and the unclassified). It was observed that the longer reaction time and higher ionic strength led to the formation of more N-heterocyclic chromophores and the increasing of the light-absorbance of the mixture. The added inorganic ions were proposed to make the aqueous phase somewhat viscous so that the molecules were prone to undergo consecutive and intramolecular reactions to form the heterocycles. In general, this study revealed that the enhanced ionic strength and prolonged reaction time had the promotion effect on the light-absorbing SOC formation. It implies that the aldehyde-derived aqueous-phase SOC would contribute more light-absorbing particulate matter in the industrial or populated area where inorganic ions are abundant.


Assuntos
Compostos Orgânicos , Material Particulado , Material Particulado/análise , Compostos Orgânicos/análise , Espectrometria de Massas/métodos , Iminas/análise , Íons , Concentração Osmolar , Aerossóis/análise
4.
Ann Noninvasive Electrocardiol ; 28(3): e13037, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36625433

RESUMO

Coronary artery spasm (CAS) can cause unstable angina, and the treatment of this disease is controversial. We report an elderly male patient who was admitted to hospital due to chest tightness. CAG showed that 70% stenosis in the middle of the right coronary artery (RCA). A bioresorbable scaffold (BRS) was implanted in the lesion under the guidance of optical coherence tomography (OCT). One year later, the patient's symptoms were relieved. The repeated CAG showed that the stent was good. BRS implantation under the guidance of treadmill test and OCT is one of treatment options for CAS patients.


Assuntos
Doença da Artéria Coronariana , Vasoespasmo Coronário , Intervenção Coronária Percutânea , Humanos , Masculino , Idoso , Implantes Absorvíveis , Vasoespasmo Coronário/diagnóstico por imagem , Vasoespasmo Coronário/cirurgia , Angiografia Coronária , Tomografia de Coerência Óptica/métodos , Teste de Esforço , Resultado do Tratamento , Eletrocardiografia , Intervenção Coronária Percutânea/métodos , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Doença da Artéria Coronariana/diagnóstico
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(7): 839-846, 2022 Jul 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-36039579

RESUMO

OBJECTIVES: Chronic pain lasts for more than 3 months and is often associated with negative emotions such as depression and anxiety. Long-term chronic pain stress can lead to plastic changes in hippocampal structure and function. In addition to its analgesic effect, gabapentin also has certain cerebral protective effects. This study aims to observe the effect of gabapentin on neurogenesis in hippocampal dentate gyrus (DG) of the adult rats with co-disease of chronic pain and depression. METHODS: The adult rats were randomly divided into 4 groups: A sham operation (Sham) group, a comorbidity model+normal saline (CCI+Veh) group (1 mL saline), a comorbidity model+low-dose gabapentin (CCI+LG) group (diluting gabapentin with normal saline to 1 mL at the dose of 30 mg/kg), and a comorbidity model+high-dose gabapentin (CCI+HG) group (diluting gabapentin with normal saline to 1 mL at the dose of 100 mg/kg) (8 rats per group). The comorbidity model was established by sciatic nerve encirclement. On the 30th day after operation, normal saline, low-dose gabapentin, and high-dose gabapentin were given intraperitoneally, respetively, for 7 consecutive days. The paw withdrawal mechanical threshold (PWMT) of the right hindlimb was measured before the operation and on the 7th, 14th, 21th, 28th, and 40th day after the operation. The time of immobility and sugar water preference rate were measured by forced swimming test and sugar water preference test, respectively, on the 28th and 40th day after the operation. The number of doublecortin (DCX) positive neurons and the expression of brain-derived neurotrophic factor (BDNF) in hippocampal dentate gyrus were observed by immunohistochemical staining, and the morphological changes of the hippocampal neurons were observed by Golgi staining. RESULTS: Compared with the Sham group, the PWMT of the CCI comorbidity model rats reached the lowest level on the 7th day after the operation and lasted until the 28th day after the operation, and remained at a low level on the 40th day after the operation (all P<0.05). Compared with the CCI+Veh group, the PWMT in the CCI+LG group and the CCI+HG group was increased on the 40th day after the operation (all P<0.05). Compared with the Sham group, the time of immobility in the CCI comorbidity model rats was increased significantly (all P<0.01) and the sugar water preference rate was decreased significantly (all P<0.01) on the 28th day after the operation. Compared with the CCI+Veh group, the time of immobility in the CCI+HG group was shortened (P<0.05) and the sugar water preference rate was significantly increased (P<0.01) on the 40th day after the operation. Compared with the CCI+Veh group, the number of DCX positive cells in hippocampal DG of the CCI+LG group and the CCI+HG group was increased, and that in the CCI+HG group was increased more significantly (P<0.05). Compared with the Sham group, the expression of BDNF in hippocampal DG was decreased in the CCI+Veh group (P<0.05). Compared with the CCI+Veh group, the expression of BDNF in hippocampal DG and the length of dendritic spines of the hippocampal neurons were increased in the CCI+HG group (all P<0.05). CONCLUSIONS: Gabapentin can relieve chronic pain and depression-like behavior in rats with chronic pain and depression, and promote neurogenesis of hippocampal dentate gyrus neurons.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Dor Crônica , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Dor Crônica/tratamento farmacológico , Giro Denteado/metabolismo , Depressão/tratamento farmacológico , Gabapentina , Hipocampo/metabolismo , Neurogênese , Ratos , Ratos Sprague-Dawley , Solução Salina , Açúcares , Água
6.
J Mol Cell Cardiol ; 153: 1-13, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33307094

RESUMO

Autophagy plays a deleterious role in ischemic myocardial injury. The deacetylase SIRT1 is a well-established regulator of autophagy that can be modified by the ubiquitin-like protein SUMO1. Our previous work demonstrated that another ubiquitin-like protein, FAT10, exerts cardioprotective effects against myocardial ischemia by stabilizing the caveolin-3 protein; however, the effects of FAT10 on autophagy through SIRT1 are unclear. Here, we constructed a Fat10-knockout rat model to evaluate the role of FAT10 in autophagy. In vivo and in vitro assays confirmed that FAT10 suppressed autophagy to protect the heart from ischemic myocardial injury. Mechanistically, FAT10 was mainly involved in the regulation of the autophagosome formation process. FAT10 affected autophagy through modulating SIRT1 degradation, which resulted in reduced SIRT1 nuclear translocation and inhibited SIRT1 activity via its C-terminal glycine residues. Notably, FAT10 competed with SUMO1 at the K734 modification site of SIRT1, which further reduced LC3 deacetylation and suppressed autophagy. Our findings suggest that FAT10 inhibits autophagy by antagonizing SIRT1 SUMOylation to protect the heart from ischemic myocardial injury. This is a novel mechanism through which FAT10 regulates autophagy as a cardiac protector.


Assuntos
Autofagia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Substâncias Protetoras/metabolismo , Sirtuína 1/metabolismo , Ubiquitinas/metabolismo , Animais , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Ratos Sprague-Dawley , Sirtuína 1/genética , Ubiquitinas/genética
7.
Exp Mol Pathol ; 118: 104595, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33359036

RESUMO

PURPOSE: To explore the role of SNHG16 in coronary heart disease (CHD) and its effect on vascular smooth muscle cells via miR-218-5p. METHODS: A quantitative real time polymerase chain reaction (qRT-PCR) assay was carried out to determine the expression of serum SNHG16 and miR-218-5p in the observation group before and after treatment and in the control group. Then, receiver operating characteristic (ROC) curves were drawn to analyze the value of SNHG16 and miR-218-5p in the diagnosis and prognosis prediction of CHD. Furthermore, purchased coronary artery smooth muscle cells (HCASMC) were transfected with SNHG16 mimics, SNHG16 inhibitor, miR-218-5p mimics, miR-218-5p inhibitor, or negative control, and then the cell proliferation, migration, apoptosis, and apoptosis-related proteins (Bax, Bcl-2, and Caspase-3) and Wnt/ß-catenin signaling pathway-related proteins (c-myc and ß-catenin) in the cells were detected. RESULTS: Both SNHG16 and miR-218-5 had good predictive value for the development and recurrence of CHD (P < 0.001). In addition, cell experiments showed that inhibition of SNHG16 weakened the proliferation and migration of HCASMC cells and intensified their apoptosis, SNHG16 and miR-218-5p had the same binding sites, and the dual luciferase reporter assay revealed that the fluorescence activity of HG16-WT was inhibited by transfected miR-mimics, but enhanced by transfected miR-inhibitor (both P < 0.050). Furthermore, the rescue experiment revealed that the effect of inhibiting SNHG16 on HCASMC cells was completely reversed by miR-218-5p (P > 0.050). CONCLUSIONS: Highly expressed SNHG16 targetedly regulates miR-218-5p and promotes the proliferation and migration of HCASMC via the Wnt/ß-catenin signaling pathway, giving rise to CHD.


Assuntos
Biomarcadores/metabolismo , Doença das Coronárias/patologia , Regulação da Expressão Gênica , MicroRNAs/genética , Músculo Liso Vascular/patologia , RNA Longo não Codificante/genética , Adulto , Apoptose , Estudos de Casos e Controles , Movimento Celular , Proliferação de Células , Células Cultivadas , Doença das Coronárias/genética , Doença das Coronárias/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/metabolismo , Prognóstico
9.
J Electrocardiol ; 62: 14-19, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745730

RESUMO

BACKGROUND: Conflicting results have been reported on the predictive value of the electrocardiographic left ventricular hypertrophy (LVH) in the general population. This meta-analysis sought to compare the predictive value of different electrocardiographic criteria of LVH in the general population. METHODS: We comprehensively searched PubMed and Embase databases until May 9, 2020 to identify observational studies investigating the predictive value of different electrocardiographic criteria for LVH (Sokolow-Lyon voltage, Cornell voltage or Cornell product) in the general population. Outcome measures were major adverse cardiovascular events (MACEs), cardiovascular or all-cause mortality. RESULTS: Ten studies enrolling 58,400 individuals were included. Comparison with and without electrocardiographic LVH, the pooled risk ratio (RR) of MACEs was 1.62 (95% confidence interval [CI] 1.40-1.89) for the Sokolow-Lyon voltage criteria, 1.70 (95% CI 1.27-2.29) for the Cornell voltage criteria, and 1.56 (95% CI 1.17-2) for the Cornell product criteria. The pooled RR of all-cause mortality was 1.47 (95% CI 1.10-1.97) for the Sokolow-Lyon voltage criteria and 1.87 (95% CI 1.29-2.71) for the Cornell voltage criteria. Furthermore, the pooled RR of cardiovascular mortality was 1.38 (95% CI 1.19-1.60) for the Sokolow-Lyon criteria, 1.66 (95% CI 1.24-2.33) for the Cornell voltage criteria, and 1.82 (95% CI 0.65-5.09) for the Cornell product criteria. CONCLUSIONS: Different electrocardiographic criteria for evaluating LVH had a similar value in predicting MACEs among the general population. LVH detected by the Cornell voltage appeared to have a stronger predictive value in prediction of cardiovascular or all-cause mortality.


Assuntos
Hipertensão , Hipertrofia Ventricular Esquerda , Eletrocardiografia , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico , Razão de Chances , Risco
10.
Int Heart J ; 61(1): 153-159, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31956131

RESUMO

A previous study and a gene-annotation enrichment analysis for potential targets of the microRNA miR-202-3p both suggest that this microRNA might be implicated in cardiovascular and metabolic diseases. In the present study, the role of miR-202-3p in the pathogenesis of coronary heart disease (CHD) was explored. We conduct a case-control study to detect the expression levels of miR-202-3p in peripheral blood cells and found that miR-202-3p expression was significantly higher in CHD cases than in controls (P < 0.001). miR-202-3p levels were negatively correlated with platelet distribution width (r = -0.348, P = 0.002) and mean platelet volume (r = -0.29, P = 0.01). Further functional analyses suggested that stimulation with oxidized low-density lipoprotein (ox-LDL) induced miR-202-3p expression, and that this microRNA suppressed the formation of ox-LDL-induced macrophage foam cells derived from THP-1 cells in a feedback manner. In addition, miR-202-3p overexpression modulated the expression of several key genes involved in foam cell formation, including that of ABCG4, NCEH1I, and SCARB2. In summary, miR-202-3p was associated with CHD, exerting a protective role against CHD by feedback suppression of ox-LDL-induced macrophage foam cell formation.


Assuntos
Povo Asiático/genética , Doença das Coronárias/genética , Células Espumosas/citologia , MicroRNAs/genética , Idoso , Estudos de Casos e Controles , Células Cultivadas , Feminino , Células Espumosas/metabolismo , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Lipoproteínas LDL/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Células THP-1 , Regulação para Cima
11.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 42(5): 511-516, 2017 May 28.
Artigo em Zh | MEDLINE | ID: mdl-28626095

RESUMO

OBJECTIVE: To detect the effect of pulse radiofrequency (PRF) treatment on the neuropathic pain established by L5-spinal nerve ligation (SNL) on rats, and to investigate if PRF treatment would affect the expression of autophagy related protein LC3 and autophagy related receptor P62 at the dorsal horn.
 Methods: A total of 36 male Sprague-Dawley rats were randomly divided into 3 groups: a Sham group, a SNL group, and a SNL+PRF group. The 50% paw withdrawal mechanical threshold (PWMT) was detected at 1 day before and 1, 3, 7, 14 and 28 days post-operation by using Von-Frey filaments. The autophagy related protein LC3 and autophagy related receptor P62 were investigated by Western blot.
 Results: Compared with the Sham group, the PWMT significantly decreased in the SNL group at each time points (P<0.05); in SNL+PRF group, PRF treatment could elevate the PWMT at the 1st day post-operation and lasted for 28 days (P<0.05). What's more, SNL could elevate the LC3-II and P62 levels at the 7th day post-operation (P<0.05), which were decreased by the PRF treatment (P<0.05).
 Conclusion: PRF treatment could improve SNL-induced the neuropathic pain, which might be partly due to the regulatory effects on the autophagy levels at the spinal dorsal horn.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Autofagia/fisiologia , Neuralgia/terapia , Tratamento por Radiofrequência Pulsada , Animais , Modelos Animais de Doenças , Ligadura , Masculino , Neuralgia/etiologia , Neuralgia/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
13.
Front Immunol ; 15: 1364401, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545101

RESUMO

The emerging extracellular vesicles technologies is an advanced therapeutic approach showing promising potential for addressing inflammatory diseases. These techniques have been proven to have positive effects on immune modulation and anti-inflammatory responses. With these advancements, a comprehensive review and update on the role of extracellular vesicles in inflammatory diseases have become timely. This review aims to summarize the research progress of extracellular vesicle technologies such as plant-derived extracellular vesicles, milk-derived extracellular vesicles, mesenchymal stem cell-derived extracellular vesicles, macrophage-derived extracellular vesicles, etc., in the treatment of inflammatory diseases. It elucidates their potential significance in regulating inflammation, promoting tissue repair, and treating diseases. The goal is to provide insights for future research in this field, fostering the application and development of extracellular vesicle technology in the treatment of inflammatory diseases.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Humanos , Vesículas Extracelulares/fisiologia , Inflamação/terapia , Células-Tronco Mesenquimais/fisiologia
14.
Pharmazie ; 68(8): 677-80, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24020123

RESUMO

Mas is a functional binding site for angiotensin (Ang)-(1-7), a critical component of the renin-angiotensin system that is involved in processing nociceptive information. A recent study reported the localization of Mas in rat dorsal root ganglia (DRG) and demonstrated that Ang-(1-7) produced a dose-dependent peripheral antinociceptive effect in rats through the Mas receptor by an opioid-independent mechanism. In the present study, we for the first time examined the effect of propofol on Mas expression in cultured DRG neurons. We treated rat DRG neurons with propofol at different concentrations (0.1, 0.5, 1, 5 or 10 microM) for different length of time (0.5, 1, 2, 4 or 6 h) with or without transcription inhibitor actinomycin D or different kinase inhibitors. Propofol increased the Mas receptormRNA level in a statistically significant dose- and time-dependent manner within 4 h, which led to dose-dependent up-regulation of the Mas receptor protein level as well as Ang-(1-7) binding on the cell membrane. Actinomycin D (1 mg/ml) and p38 mitogen-activated protein kinase inhibitor PD169316 (25 microM) completely abolished the effect of propofol on Mas receptor expression in DRG neurons. In conclusion, we demonstrate that propofol markedly up-regulates Mas receptor expression at the transcription level in DRG neurons by a p38 MAPK-dependent mechanism. This study provides new insights into the mechanisms of action of propofol in peripheral antinociception, and suggests a new regulatory mechanism on the Ang-(1-7)/Mas axis in the peripheral nervous system.


Assuntos
Anestésicos Intravenosos/farmacologia , Gânglios Espinais/metabolismo , Neurônios/metabolismo , Propofol/farmacologia , Proteínas Proto-Oncogênicas/biossíntese , Receptores Acoplados a Proteínas G/biossíntese , Angiotensina I/metabolismo , Animais , Western Blotting , Células Cultivadas , Dactinomicina/farmacologia , Gânglios Espinais/citologia , Imidazóis/farmacologia , Indicadores e Reagentes , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
15.
Front Oncol ; 13: 1260325, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38044985

RESUMO

Objective: To identify risk factors of secondary pelvic malignant neoplasms (SPMNs) among prostate cancer (PCa) patients treated with radiotherapy. Simultaneously, population-based data were used to validate the high risk of SPMNs in PCa patients with radiotherapy. Materials and methods: We identified male patients diagnosed with PCa (localized and regional) as the first primary cancer and pelvic malignant neoplasm (including bladder and rectal cancer) as secondary cancer from Surveillance, Epidemiology, and End Results database (1975-2020). An external validation cohort was obtained from the First Affiliated Hospital of Nanchang University. The Fine-Gray competing risk regression and Poisson regression were utilized to evaluate the risk of SPMNs development. Poisson regression was also performed to calculate the standardized incidence ratio (SIR). The Kaplan-Meier method was used to assess the overall survival (OS) of patients with SPMNs. Results: 89397 PCa patients treated with radiotherapy were enrolled. We identified associated factors of SPMNs, including age at diagnosis, race, year of diagnosis, marital status, radiation strategy and latency. In the multivariable competing risk regression model and Poisson regression model, a significantly higher risk of SPMNs development was observed in patients over 50 years(P<0.05), white patients(P<0.001), unmarried patients and treated with brachytherapy combined with external beam radiotherapy or brachytherapy(P<0.05). Patients treated with radiotherapy had a higher bladder and rectal cancer incidence than the general population. Patients who developed SPMNs showed poorer OS. Conclusion: We identified several risk factors associated with SPMNs and confirmed a relatively higher incidence of bladder and rectal cancer among PCa patients with radiotherapy. These results help tailor treatment and surveillance strategies.

16.
Anesth Analg ; 115(4): 973-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23002259

RESUMO

BACKGROUND: The directional flow of injection through a Whitacre needle can be used to modify the level of sensory blockade. We hypothesized that injection of hyperbaric local anesthetic through a Whitacre needle with the bevel oriented laterally can produce a more symmetric sensory block. METHODS: Patients scheduled for lower limb surgery under spinal anesthesia with the patient in lateral decubitus position were randomized to receive 10 mg, 0.5% hyperbaric bupivacaine with the Whitacre needle orifice in 1 of 2 orientations, cephalad and lateral. The patient's position was maintained for 15 min after the injection, and sensory blocks were recorded. The primary outcome was the sensory levels between the dependent and nondependent side. The Wilcoxon-Mann-Whitney U-test odds was used to compare unpaired nonparametric data. For the paired samples, 95% confidence intervals (CI) of differences between group medians were calculated using the Hodges-Lehman estimator for the median difference in number of blocked segments. RESULTS: There was no significant difference in block level between dependent and nondependent sides in the lateral group. The Hodges-Lehmann point estimator was 0.5% and 95% CI was 0-2.5, suggesting a more symmetric sensory block in patients in the lateral decubitus position maintained for a sufficient period of time. A significantly lower level of blockade was noticed on the nondependent side compared to the dependent side in the cephalad group. The Hodges-Lehmann point estimator was 2.5 segments and 95% CI was 0.5-5. CONCLUSIONS: Injection of 10 mg of 0.5% hyperbaric bupivacaine with the bevel of the Whitacre needle oriented laterally produces more symmetric sensory levels of blockade between the dependent and nondependent sides.


Assuntos
Raquianestesia/instrumentação , Raquianestesia/métodos , Bloqueio Nervoso Autônomo/instrumentação , Bloqueio Nervoso Autônomo/métodos , Agulhas , Postura , Adulto , Bupivacaína/administração & dosagem , Feminino , Humanos , Injeções , Masculino , Fatores de Tempo
17.
Zhonghua Fu Chan Ke Za Zhi ; 47(11): 833-8, 2012 Nov.
Artigo em Zh | MEDLINE | ID: mdl-23302124

RESUMO

OBJECTIVE: To investigate the effect of estrogen on expression of matrix GLA protein (MGP) in ovariectomized Sprague-Dawley (SD) rats and the role of estrogen in improving postmenopausal osteoporosis. METHODS: Thirty-six SD female rats were allocated into 3 groups randomly, every 12 rats in ovariectomized group (OVX group), estrogen group (E group) and control group (sham group). Rats in OVX and E group all underwent bilateral ovariectomy, those rats in E group were given by estradiol benzoate intramuscularly after 3 weeks of ovariectomy. Rats in sham group underwent bilateral lipectomy near the ovary. All rats were kept the urine and the serum every three weeks and were sacrificed after 15 weeks. The pathology changes of uterus, lumbar vertebral bones were observed by immunohistochemistry. Bone mineral density (BMD) of lumbar vertebra of rats was determined by dual energy X ray absorptiometry (DEXA). The content of MGP in serum and urine was determined by ELISA. Expression of undercarboxylated matrix GLA Protein (MGP) was detected by immunohistochemistry. Relative quantification of MGP mRNA expression in lumbar vertebra bone was detected by Fluorescent real-time quantitative polymerase chain reaction. RESULTS: (1) After 15 weeks of ovariectomized, the endometrium of uterus and lumbar vertebra exhibit remarkable pathologic changes in OVX group. The serum estrogen of (454 ± 66) pmol/L in OVX group were lower than in (527 ± 77) pmol/L in sham group and (556 ± 80) pmol/L in E group significantly (P < 0.05). The BMD of lumbar vertebra of (0.263 ± 0.030) g/cm(2) in OVX group were lower than (0.295 ± 0.024) g/cm(2) in sham group and (0.279 ± 0.024) g/cm(2) in E group significantly (P < 0.01). (2) The serum MPG protein in OVX group and E group showed decreased trends after ovariectomized, which were (104 ± 64) ng/L in OVX group and (134 ± 6) ng/L in E group at 9 weeks, which reached statistical difference (P < 0.05). However, MGP in urine in sham group did not exhibit significant difference after 15 weeks of surgery (P > 0.05). The MGP in urine of E group showed increased trends after 12 weeks of surgery, which reached (110.0 ± 3.4) ng/L at 15 weeks, in the mean time, it was found that (86.5 ± 2.5) ng/L of MGP in urine in OVX group, which showed significant difference (P < 0.05). (3) MGP could be observed in lumbar vertebra in OVX group by immunochemistry staining. In the other two groups, the expression of MGP was not dominant. (4) Relative quantification of MGP mRNA expression in lumbar vertebra was defined as 1 in OVX group, when compared with 0.289 ± 0.260 in E group and 0.103 ± 0.098 in sham group, the difference showed statistically significant (P < 0.01). CONCLUSION: Estrogen could increase the expression of MGP mRNA and protein in ovariectomized rats and might play an important role in improving postmenopausal osteoporosis.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Estradiol/análogos & derivados , Proteínas da Matriz Extracelular/metabolismo , Vértebras Lombares/metabolismo , Ovariectomia , Animais , Densidade Óssea/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/sangue , Proteínas de Ligação ao Cálcio/genética , Endométrio/patologia , Ensaio de Imunoadsorção Enzimática , Estradiol/administração & dosagem , Estradiol/farmacologia , Estrogênios/sangue , Proteínas da Matriz Extracelular/sangue , Proteínas da Matriz Extracelular/genética , Feminino , Imuno-Histoquímica , Vértebras Lombares/patologia , Osteoporose/metabolismo , Osteoporose/prevenção & controle , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Proteína de Matriz Gla
18.
Sci Rep ; 12(1): 4385, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35288629

RESUMO

Recently, the application and development of flexible microwave-absorption composites based on silicone rubber have gradually become a research hot spot. In this study, methyl vinyl phenyl silicone rubber (MPVQ)/carbonyl iron particles (CIPs)/graphene (GR) composites were prepared by mechanical blending, and the effects of thermal-ageing temperature on the microwave-absorption properties of the composites were investigated. The mechanism of the thermal-ageing temperature's effects on microwave-absorption behaviour was identified. The results show that unaged composites have superior microwave-absorption properties, with a minimum reflection loss (RLmin) of - 87.73 dB, a lowest thickness of 1.46 mm, and an effective absorption bandwidth (EAB, RL < - 10 dB) reaching 5.8 GHz (9.9-15.7 GHz). With ageing at 240 °C for 24 h, the RLmin at a frequency of 5.48 GHz is - 45.55 dB with a thickness of 2.55 mm, and the EAB value reaches 2 GHz (range 4.6-6.6 GHz). In the thermal-ageing process, a crosslinking reaction occurs in MPVQ with an increase in crosslinking density from 5.88 × 10-5 mol g-1 (unaged) to 4.69 × 10-4 mol g-1 (aged at 240 °C). Simultaneously, thermal degradation of the composites leads to a reduction in the rubber concentration. In addition, a small amount of CIPs are oxidized to Fe3O4, and the remaining CIPs aggregate to generate more electrically conductive pathways. Consequently, the dielectric loss of the composites will be significantly improved, resulting in poor impedance matching. The microwave-absorption properties of the composites gradually decrease with increasing thermal-ageing temperature from 200 to 240 °C.

19.
Front Cardiovasc Med ; 9: 1052547, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36440044

RESUMO

Objective: This study aimed to identify risk factors for coronary heart disease (CHD) in patients with type 2 diabetes mellitus (T2DM), build a clinical prediction model, and draw a nomogram. Study design and methods: Coronary angiography was performed for 1,808 diabetic patients who were recruited at the department of cardiology in The Second Affiliated Hospital of Nanchang University from June 2020 to June 2022. After applying exclusion criteria, 560 patients were finally enrolled in this study and randomly divided into training cohorts (n = 392) and validation cohorts (n = 168). The least absolute shrinkage and selection operator (LASSO) is used to filter features in the training dataset. Finally, we use logical regression to establish a prediction model for the selected features and draw a nomogram. Results: The discrimination, calibration, and clinical usefulness of the prediction model were evaluated using the c-index, receiver operating characteristic (ROC) curve, calibration chart, and decision curve. The effects of gender, diabetes duration, non-high-density lipoprotein cholesterol, apolipoprotein A1, lipoprotein (a), homocysteine, atherogenic index of plasma (AIP), nerve conduction velocity, and carotid plaque merit further study. The C-index was 0.803 (0.759-0.847) in the training cohort and 0.775 (0.705-0.845) in the validation cohort. In the ROC curve, the Area Under Curve (AUC) of the training set is 0.802, and the AUC of the validation set is 0.753. The calibration curve showed no overfitting of the model. The decision curve analysis (DCA) demonstrated that the nomogram is effective in clinical practice. Conclusion: Based on clinical information, we established a prediction model for CHD in patients with T2DM.

20.
Cardiovasc Diagn Ther ; 12(1): 42-54, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35282662

RESUMO

Background: For patients with heart failure (HF), the effect of angiotensin receptor-neprilysin inhibitors (ARNIs, sacubitril/valsartan) on cardiac remodeling has been found to be superior to angiotensin-converting enzyme inhibitors (ACEI). However, little data have described the impact of early-initiation ARNI in patients with acute anterior ST-segment elevation myocardial infarction (STEMI). Methods: In this prospective, randomized, double-blind, parallel-group trial, we enrolled 131 anterior STEMI patients who were treated with primary percutaneous coronary intervention (PCI) between February 2019 and December 2019. All patients received standard STEMI management and were divided into 2 groups (ARNI/enalapril). Primary efficacy outcomes were the between-group difference in change (from baseline to 4-, 12-, and 24-week) in N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration, left ventricular ejection fraction (LVEF), and left ventricular end-systolic volumes and end-diastolic volumes (LVESV and LVEDV). Secondary outcomes were determined by a composite of death, reinfarction, outpatient HF or HF hospitalization, malignant arrhythmia, and stroke. Safety outcomes included worsening renal function, hypotension, hyperkalemia, angioedema and cough. Results: We found that NT-proBNP concentration decreased more in the ARNI group than in the enalapril group [4 weeks: ratio of ARNI vs. enalapril 0.36, 95% confidence interval (CI): 0.24 to 0.52, P<0.001; 12 weeks: 0.54, 95% CI: 0.35 to 0.79, P<0.001; 24 weeks: 0.53, 95% CI: 0.32 to 0.83, P<0.001). When compared to the enalapril group, the ARNI group patients had a significant reduction in LVEDV (P<0.001) and LVESV (P<0.001), and an improvement in LVEF (P=0.011) at 24 weeks. Secondary outcomes occurred in 13 participants (20.3%) in the ARNI group and 22 participants (34.4%) in the enalapril group [hazard ratio (HR), 0.56; 95% CI: 0.28 to 1.12; P=0.102]. The incidence of outpatient HF or HF hospitalization in the ARNI group was significantly lower than that in the enalapril group (HR, 0.36; 95% CI: 0.14 to 0.94; P=0.037). There were no significant differences in the safety between the 2 groups. Conclusions: For patients with acute anterior STEMI undergoing primary PCI, early initiation of ARNI provided significant clinical benefits. Trial Registration: Chinese Clinical Trial Registry (ChiCTR2100042944) registered on February 1, 2021.

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