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1.
Opt Express ; 32(9): 15126-15135, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859171

RESUMO

Transverse spin, a spin component with unique characteristics, provides a new dimension for plenty of applications, such as optical trapping, imaging, and communication. Here, we analyze the pure transverse spin in the Bessel beam, which is solely present in the azimuthal direction. Based on a single layer dielectric metasurface, we efficiently generate Bessel beams with pure transverse spin in a compact optical system. As designed, the transverse spin is flexibly tunable by converting the polarization of the incident light. Furthermore, in the scattered Bessel beam, the local electromagnetic field oscillates around the transverse axis, which is perpendicular to the beam propagation. At certain positions, the local polarization ellipse degenerates into a perfect circle, resulting in a ring-periodic distribution of circularly polarized points (C points) in the beam. This suggests that the local polarization demonstrates a nontrivial periodic structure. This work deepens our understanding of spin-related physics and opens a new avenue for the study and application of transverse spins in ultracompact, flat, multifunctional nanophotonic platforms.

2.
World J Clin Cases ; 11(30): 7372-7379, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37969441

RESUMO

BACKGROUND: Burkholderia pseudomallei (B. pseudomallei) is a short, straight, medium-sized Gram-negative bacterium that mostly exists alone, without a capsule or spores, has more than three flagella at one end, and actively moves. B. pseudomallei confers high morbidity and mortality, with frequent granulocytopenia in B. pseudomallei sepsis-related deaths. However, mortality may be related to hemophagocytic lymphohistiocytosis (HLH) secondary to B. pseudomallei infection. CASE SUMMARY: A 12-year-old female was referred from a local hospital to the pediatric intensive care unit with suspected septic shock and fever, cough, dyspnea, and malaise. After admission, supportive symptomatic treatments including fluid resuscitation, anti-infective therapy, mechanical ventilation, and a vasoactive drug maintenance cycle were carefully initiated. The patient became unconscious, her blood pressure could not be maintained even under the exposure of vasoactive drugs, and she experienced cardiorespiratory arrest. The patient died due to ineffective high-quality in-hospital cardiopulmonary resuscitation. A subsequent bone marrow smear examination revealed extensive phagocytosis, and the blood culture was positive for B. pseudomallei. Family history revealed a sibling death from B. pseudomallei sepsis 5 years earlier. CONCLUSION: The higher mortality rate in patients with B. pseudomallei sepsis may be related to secondary HLH after infection, wherein multiorgan dysfunction syndrome may be directly related to infection or immune damage caused by secondary HLH. Patients with B. pseudomallei can be asymptomatic and can become an infective source.

3.
Int J Biol Macromol ; 242(Pt 4): 125151, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37270127

RESUMO

Protein post-translational modifications (PTMs) are important regulators of protein functions and produce proteome complexity. SIRT1 has NAD+-dependent deacylation of acyl-lysine residues. The present study aimed to explore the correlation between lysine crotonylation (Kcr) on cardiac function and rhythm in Sirt1 cardiac-specific knockout (ScKO) mice and related mechanism. Quantitative proteomics and bioinformatics analysis of Kcr were performed in the heart tissue of ScKO mice established with a tamoxifen-inducible Cre-loxP system. The expression and enzyme activity of crotonylated protein were assessed by western blot, co-immunoprecipitation, and cell biology experiment. Echocardiography and electrophysiology were performed to investigate the influence of decrotonylation on cardiac function and rhythm in ScKO mice. The Kcr of SERCA2a was significantly increased on Lys120 (1.973 folds). The activity of SERCA2a decreased due to lower binding energy of crotonylated SERCA2a and ATP. Changes in expression of PPAR-related proteins suggest abnormal energy metabolism in the heart. ScKO mice had cardiac hypertrophy, impaired cardiac function, and abnormal ultrastructure and electrophysiological activities. We conclude that knockout of SIRT1 alters the ultrastructure of cardiac myocytes, induces cardiac hypertrophy and dysfunction, causes arrhythmia, and changes energy metabolism by regulating Kcr of SERCA2a. These findings provide new insight into the role of PTMs in heart diseases.


Assuntos
Cardiopatias , Lisina , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , Animais , Camundongos , Arritmias Cardíacas , Cardiomegalia/genética , Lisina/química , Camundongos Knockout , Processamento de Proteína Pós-Traducional , Sirtuína 1/genética , Sirtuína 1/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/química , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
4.
Front Mol Neurosci ; 16: 1097553, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36910266

RESUMO

Objective: This study aims to prove that the de novo variants in MAST4 gene are associated with neurodevelopmental disorders (NDD) with developmental delay (DD) and infantile spasm (IS) and to determine the genotype-phenotype correlations. Methods: Trio-based exome sequencing (ES) was performed on the four families enrolled in this study. We collected and systematically reviewed the four probands' clinical data, magnetic resonance images (MRI), and electroencephalography (EEG). We also carried out bioinformatics analysis by integrating published exome/genome sequencing data and human brain transcriptomic data. Results: We described four patients whose median age of seizure onset was 5 months. The primary manifestation was infantile spasms with typical hypsarrhythmia on EEG. Developmental delays or intellectual disabilities varied among the four individuals. Three de novo missense variants in MAST4 gene were identified from four families, including chr5:66438324 (c.2693T > C: p.Ile898Thr) z, chr5:66459419 (c.4412C > T: p.Thr1471Ile), and chr5:66462662 (c.7655C > G:p.Ser2552Trp). The missense variant p.Ile898Thr is mapped to the AGC-kinase C-terminal with phosphatase activity. The other variant p.Ser2552Trp is located in a phosphoserine-modified residue which may affect cell membrane stability and signal transduction. Besides, the variant p.Thr1471Ile is a recurrent site screened out in two unrelated patients. Compared to private mutations (found only in a single family or a small population) of MAST4 in the gnomAD non-neuro subset, all de novo variants were predicted to be damaging or probably damaging through different bioinformatic analyses. Significantly higher CADD scores of the variant p.Thr1471Ile indicate more deleteriousness of the recurrent site. And the affected amino acids are highly conserved across multiple species. According to the Brainspan Atlas database, MAST4 is expressed primarily in the mediodorsal nucleus of the thalamus and medial prefrontal cortex during the prenatal period, potentially contributing to embryonic brain development. Conclusion: Our results revealed that the variants of MAST4 gene might lead to neurodevelopmental disorders with developmental delay and infantile spasm. Thus, MAST4 variants should be considered the potential candidate gene in patients with neurodevelopmental disorders clinically marked by infantile spasms.

5.
Front Cardiovasc Med ; 9: 1000352, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36698959

RESUMO

Objectives: This study attempted to explore the hemodynamics and potential mechanisms driving pulmonary circulation in status of ventricular fibrillation (VF) following continuous-flow left ventricular assist device (CF-LVAD) implantation. Methods: An ovine CF-LVAD model was built in small-tailed Han sheep, with the pump speed set as 2,400 rpm. VF was induced following ventricular tachycardia using a temporary pacemaker probe to stimulate the right and left ventricular free walls. The central venous pressure (CVP), pump flow (PF), pulmonary artery flow (PAF) and other major indicators were observed and recorded after VF. Results: Low-flow systemic and pulmonary circulation could be sustained for 60 min under VF with sinus atrial rhythm after CF-LVAD implantation. The CVP gradually increased. The mean PF declined from 1.80 to 1.20 L/min, and the mean PAF decreased from 1.62 L/min to 0.87 L/min. Under VF with atrial fibrillation, the systemic and pulmonary circulation couldn't be sustained. The CVP jumped from the 5 mmHg baseline to 12 mmHg, the mean PF rapidly decreased from 3.45 L/min to 0.79 L/min, and the PAF declined from 3.94 L/min to 0.77 L/min. Conclusion: The atrial rhythm and function might be essential for the circulation maintenance in patients with VF after CF-LVAD implantation.

6.
ACS Appl Mater Interfaces ; 10(14): 11652-11662, 2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29544248

RESUMO

Heterogeneous p-n junction CdS/Cu2O nanorod arrays have been fabricated by using a facile successive ionic-layer adsorption and reaction process to grow Cu2O nanoparticles on the surface of ordered CdS nanorod arrays. The heterogeneous p-n junction nanorod arrays exhibit superior photoelectrochemical performance for hydrogen (H2) generation and high stability under visible-light irradiation. The highest photocurrent density achieved by heterogeneous nanorod array photoelectrode is 4.2 mA cm-2 in a sacrificial Na2S and Na2SO3 mixture electrolyte solution at 0 V versus Ag/AgCl, which is 4 times higher than that of a pure CdS nanorod array photoelectrode. In addition, the heterogeneous nanorod array photoelectrode achieves an incident photon conversion efficiency value of 40.5% at 470 nm. The photocatalytic hydrogen generation rate of the heterogeneous nanorod array photoelectrode reaches up to 161.2 µmol h-1, around 3-fold increase compared to that of a bare CdS photoelectrode. Furthermore, the heterogeneous p-n junction CdS/Cu2O nanorod arrays show an excellent stability under long light illumination of 7200 s. The improved photoelectrochemical performance, photocatalytic activity, and excellent stability of the heterogeneous nanorod array photoelectrode resulted from the efficient separation of photoinduced electron-hole pairs, which is achieved by the synergistic effects of CdS, Cu2O, p-n junction, and an inner electric field in the photoelectrode. The present work provides a new strategy to fabricate a heterogeneous photoelectrode. This facile strategy is expected to be utilized to fabricate electrodes of other materials for highly efficient solar-driven water splitting application.

8.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 18(8): 491-3, 2006 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16887065

RESUMO

OBJECTIVE: To evaluate the effect of angiotensin II (Ang II) and its receptor antagonist on action potential duration and L-type calcium current density of cardiac myocytes. METHODS: Single myocyte of the ventricle in guinea was isolated. Action potentials were recorded using a conventional glass microelectrode filled with 3 mol/L KCl solution. Membrane patch clamp whole cell recording technique was used to investigate L-type calcium current maximum in holding potential of -40 mV, length of time 200 ms, command potential 0 mV. RESULTS: Ang II induced arrhythmia of multiple electrophysiologic mechanisms. Action potential amplitude, 90% of action potential duration (APD90), and resting membrane potential (RMP) were significantly decreased or shortened after being perfused Ang II for 1 minute compared with controls. 30% of action potential duration (APD30), 50% of action potential duration (APD50), effective refractory period (ERP) were also shortened significantly after perfused Ang II for 3 minutes compared with controls. Ang II increased the L-type calcium maximum current density after a perfusion of 5 minutes, but losartan perfusion for 1 minute decreased the L-type calcium maximum current density, and it further decreased after perfusion for 3 minutes. However, the current voltage relationship curve was unchanged. CONCLUSION: Ang II could decrease amplitude of monophasic action potential, rest membrane potential, shorten duration of monophasic action potential and effective refractory period, increase maximum current density of voltage dependent L-type calcium, and possess the effect of inducing arrhythmia. Losartan decreased maximum current density of voltage dependent L-type calcium.


Assuntos
Angiotensina II/farmacologia , Canais de Cálcio Tipo L/efeitos dos fármacos , Losartan/farmacologia , Miócitos Cardíacos/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Canais de Cálcio Tipo L/fisiologia , Células Cultivadas , Feminino , Cobaias , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Técnicas de Patch-Clamp
9.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 17(9): 544-7, 2005 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-16146600

RESUMO

OBJECTIVE: To investigate the diagnostic and prognostic value of N-terminal pro-brain natriuretic peptide (NT-proBNP) and atrium natriuretic peptide (ANP) in chronic congestive heart failure. METHODS: Seventy-one coronary heart disease patients were enrolled in the study. Among them 58 patients were accompanied by heart failure and 13 with no heart failure. Plasma NT-ProBNP was determined with enzyme linked immunoadsorbent assay method, and plasma ANP was determined with radioimmunoassay method. The results were compared with those of 30 healthy individuals. All patients were followed up accordingly. RESULTS: Compared with patients with no heart failure and healthy individuals, the patients with heart failure had a higher plasma NT-proBNP and ANP contents. Cardiac function grade IV patients had a significantly higher plasma NT-ProBNP than cardiac function grade II and III patients, and their plasma ANP level was significantly higher than that of cardiac function grade III patients, but there was no significantly difference in ANP content between cardiac function grade IV and II. The diagnostic sensitivity of NT-proBNP and ANP was 94.38% and 75.86%, respectively. The diagnostic specificity of NT-proBNP and ANP was 96.67%, 83.33%, respectively. In the heart failure group, after being followed up for (11.35+/-1.69) months, it was found that there was no significant difference in the plasma NT-proBNP and ANP between the deaths and surviving patients. CONCLUSION: The diagnostic value of NT-proBNP in chronic heart failure is higher than that of ANP. According to our follow-up result, the plasma NT-proBNP and ANP can not be relied upon to predict short-term cardiogenic death in heart failure.


Assuntos
Fator Natriurético Atrial/sangue , Insuficiência Cardíaca/diagnóstico , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Doença Crônica , Doença das Coronárias/complicações , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Prognóstico
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