Enhanced response over wavelength range of 7-12 µm for quantum wells in asymmetric micro-pillars.

Efficient coupling in broad wavelength range is desirable for wide-spectrum infrared light detection, yet this is a challenge for intersubband transition in semiconductor quantum wells (QWs). High-Q cavities mostly intensify the absorption at peak wavelengths but with shrinking bandwidth. Here, we propose a novel approach to expand the operating spectral range of the Quantum Well Infrared Photodetectors (QWIPs). By processing the QWs into asymmetric micro-pillar array structure, the device demonstrates a substantial enhancement in spectral response across the wavelength from 7.1 µm to 12.3 µm with guided mode resonance (GMR) effects. The blackbody responsivity is then increased by 3 times compared to that of the 45° polished edge-coupled counterpart. Meanwhile, the dark current density remains unchanged after the deep etching process, which will benefit the electrical performance of the detector with reduced volume duty ratio. In contrast to the symmetric micro-pillar array that contains simple resonance mode, the detectivity of QWIP in asymmetric pillar structure is found to be improved by 2-4 times within the range of 9.5 µm to 15 µm.

Enhanced absorption of infrared light for quantum wells in coupled pillar-cavity arrays.

Periodic pillars of semiconductor in sub-wavelength size can serve multiple roles as diffracting, trapping and absorbing light for effective photoelectric conversion which has been intensively studied in the visible range. Here, we design and fabricate the micro-pillar arrays of AlGaAs/GaAs multi quantum wells(QWs) for high performance detection of long wavelength infrared light. Compared to its planar counterpart, the array offers 5.1 times intensified absorption at peak wavelength of 8.7 µm with 4 times shrinked electrical area. It's illustrated by simulation that the normal incident light is guided in the pillars by HE11 resonant cavity mode to form strengthened Ez electrical field, which enables the inter-subband transition of n-type QWs. Moreover, the thick active region of dielectric cavity that contains 50 periods of QWs with fairly low doping concentration will be beneficial to the optical and electrical merits of the detectors. This study demonstrates an inclusive scheme to substantially raise the signal to ratio of infrared detection with all-semiconductor photonic structures.

Efficacy and feasibility of amniotic membrane for the treatment of burn wounds: A meta-analysis.

BACKGROUND: Burns cause a huge economic burden to society, and the wounds can be very difficult to manage. Clinical experience suggests that amniotic membrane (AM) is an economical and effective biological dressing for burns. However, few systematic reviews or meta-analyses have been published on such use. We aimed to evaluate the role of AM dressings in burn wounds. METHODS: A systematic search of the PubMed, Cochrane, Embase, and Web of Science databases was conducted in March 2020. The search was conducted to identify randomized control trials that compared selected features of AM with those of other dressings, such as silver sulfadiazine, polyurethane membrane, and honey. For skin-grafted wounds, we compared AM-covered skin grafts and traditional staple-fixed skin grafts. Outcomes of interest for the efficacy analysis included wound infection, pain, itching, scarring, and healing time. The number of adverse events in each treatment group, the rate of withdrawal because of adverse effects, the cost of treatment, and patient acceptability were assessed for the feasibility analysis. RESULTS: Eleven randomized controlled trials with 816 participants total were identified in our review. Amniotic membrane treatment was more effective than conventional methods, silver sulfadiazine, and polyurethane membrane in treating burn wounds, but AM appears to be less effective than honey. No reports of AM-related disease transmission or adverse reactions were described in the included articles. CONCLUSION: Amniotic membrane has beneficial effects in treating burn wounds; however, the evidence needs to be strengthened by further robust randomized controlled trials. LEVEL OF EVIDENCE: Systematic Review/Meta-analysis, level III.

1α, 25-dihydroxyvitamin D3 inhibits transforming growth factor ß1-induced epithelial-mesenchymal transition via ß-catenin pathway.

BACKGROUND: The transforming growth factor ß1 (TGF-ß1)-induced epithelial-mesenchymal transition (EMT) has been proven associated with the pathogenesis of asthmatic airway remodeling, in which the Wnt/ß-catenin pathway plays an important role, notably with regard to TGF-ß1. Recent studies have shown that 1α, 25-dihydroxyvitamin D3(1α, 25(OH)2D3) inhibits TGF-ß1-induced EMT, although the underlying mechanism have not yet been fully elucidated. METHODS: Alveolar epithelial cells were exposed to 1α, 25(OH)2D3, ICG-001, or a combination of both, followed by stimulation with TGF-ß1. The protein expression of E-cadherin, α-smooth muscle actin, fibronectin, and ß-catenin was analyzed by western blotting and immunofluorescence analysis. The mRNA transcript of Snail was analyzed using RT-qPCR, and matrix metalloproteinase 9 (MMP-9) activity was analyzed by gelatin zymogram. The activity of the Wnt/ß-catenin signaling pathway was analyzed using the Top/Fop flash reporters. RESULTS: Both 1α, 25(OH)2D3 and ICG-001 blocked TGF-ß1-induced EMT in alveolar epithelial cells. In addition, the Top/Fop Flash reporters showed that 1α, 25(OH)2D3 suppressed the activity of the Wnt/ß-catenin pathway and reduced the expression of target genes, including MMP-9 and Snail, in synergy with ICG-001. CONCLUSION: 1α, 25(OH)2D3 synergizes with ICG-001 and inhibits TGF-ß1-induced EMT in alveolar epithelial cells by negatively regulating the Wnt/ß-catenin signaling pathway.

Application of pulse index continuous cardiac output system in elderly patients with acute myocardial infarction complicated by cardiogenic shock: A prospective randomized study.

BACKGROUND: Cardiogenic shock (CS) secondary to acute myocardial infarction (AMI) complicates management of the condition, and often leads to poor prognosis. Prompt and accurate monitoring of cardiovascular and accompanying hemodynamic changes is crucial in achieving adequate management of the condition. Advances in technology has availed procedures such as pulse index continuous cardiac output (PiCCO), which can offer precise monitoring of cardiovascular functions and hemodynamic parameters. In this study, PiCCO is evaluated for its potential utility in improving management and clinical outcomes among elderly patients with AMI complicated by CS. AIM: To assess whether use of the PiCCO system can improve clinical outcomes in elderly patients with AMI complicated by CS. METHODS: Patients from emergency intensive care units (EICU) or coronary care units (CCU) were randomized to receive PiCCO monitoring or not. The APACHE II score, SOFA score, hs-TnI, NT-proBNP, PaO2/FiO2 ratio and lactate levels on day 1, 3 and 7 after treatment were compared. The infusion and urine volume at 0-24 h, 24-48 h and 48-72 h were recorded, as were the cardiac index (CI), extravascular lung water index (EVLWI), intrathoracic blood volume index (ITBVI) and global end diastolic volume index (GEDVI) at similar time intervals. RESULTS: Sixty patients with AMI complicated by CS were included in the study. The PiCCO group had a significantly lower APACHE II score, SOFA score, hs-TnI and NT-proBNP levels on day 1, 3 and 7 after treatment. The infusion and urine volume during 0-24 h in the PiCCO group were significantly greater, and this group also showed significantly higher ADL scores. Furthermore, the PiCCO group spent lesser days on vasoactive agents, mechanical ventilation, and had a reduced length of stay in EICU/CCU. Additionally, the CI was significantly higher at 48 h and 72 h in the PiCCO group compared with that at 24 h, and the EVLWI, ITBVI and GEDVI were significantly decreased at 48 h and 72 h. CONCLUSION: Applying the PiCCO system could improve the clinical outcomes of elderly patients with AMI complicated by CS.

Erasure of striatal chondroitin sulfate proteoglycan-associated extracellular matrix rescues aging-dependent decline of motor learning.

Cognitive decline is a feature of aging. Accumulating evidence suggests that the brain extracellular matrix (ECM) is involved in the process of aging-dependent cognitive impairment and neurodegeneration by regulating synaptic neurotransmission and affecting neuroplasticity. Age-related changes in brain structure and cognition are not uniform across the whole brain. Being one of the most vulnerable brain regions to aging-dependent alterations, striatum is integral to several central nervous system functions, such as motor, cognition, and affective control. However, the striatal ECM is largely understudied. We first describe 2 major types of chondroitin sulfate proteoglycan (CSPG)-associated ECM in striatum: perineuronal nets and diffusive ECM. Both types of ECM accumulate in an aging-dependent manner. The accumulation of CSPG-associated ECM correlates with aging-dependent decline in striatum-related cognitive functions, including motor learning and working memory. Enzymatic depletion of CSPG-associated ECM in aged mice via chondroitinase ABC significantly improves motor learning, suggesting that changes in neural ECM CSPGs regulate striatal plasticity. Our study provides a greater understanding of the role of neural ECM underlying striatal plasticity, which is an important precursor to design appropriate therapeutic strategies for normal and pathologic aging.

Inhibition of allergic airway inflammation by antisense-induced blockade of STAT6 expression.

BACKGROUND: The signal transducer and activator of transcription 6 (STAT6) expression in lung epithelial cells plays a pivotal role in asthma pathogenesis. Activation of STAT6 expression results in T helper cell type 2 (Th2) cell differentiation leading to Th2-mediated IgE production, development of allergic airway inflammation and hyperreactivity. Therefore, antagonizing the expression and/or the function of STAT6 could be used as a mode of therapy for allergic airway inflammation. METHODS: In this study, we synthesized a 20-mer phosphorothioate antisense oligonucleotide (ASODN) overlapping the translation starting site of STAT6 and constructed STAT6 antisense RNA (pANTI-STAT6), then transfected them into murine spleen lymphocytes and analyzed the effects of antagonizing STAT6 function in vitro and in a murine model of asthma. RESULTS: In vitro, we showed suppression of STAT6 expression and interleukin (IL)-4 production of lymphocytes by STAT6 ASODN. This effect was more prominent when cells were cultured with pANTI-STAT6. In a murine model of asthma associated with allergic pulmonary inflammation in ovalbumin (OVA)-sensitized mice, local intranasal administration of fluorescein isothiocyanate (FITC)-labeled STAT6 ASODN to DNA uptake in lung cells was accompanied by a reduction of intracellular STAT6 expression. Such intrapulmonary blockade of STAT6 expression abrogated signs of lung inflammation, infiltration of eosinophils and Th2 cytokine production. CONCLUSION: These data suggest a critical role of STAT6 in the pathogenesis of asthma and the use of local delivery of STAT6 ASODN as a novel approach for the treatment of allergic airway inflammation such as in asthma.

Depression, anxiety and influencing factors in patients with acute pulmonary embolism.

BACKGROUND: Psychological distress has been widely studied in many cardiovascular and pulmonary diseases, but the condition in acute pulmonary embolism (APE) is unknown. The purpose of this study was to investigate levels of depression and anxiety and their influencing factors in APE patients. METHODS: Sixty consecutive patients with APE were subjected to investigation of depression and anxiety by the Beck Depression Inventory and State-Trait Anxiety Inventory, and 60 community-based subjects were enrolled as controls. APE patients were stratified as high-risk, intermediate-risk and low-risk according to the disease severity. Scores of depression and anxiety were compared by statistical analysis using paired t tests between APE patients and controls, and by analysis of variance within the APE patients with the three risk stratification. Factors influencing depression and anxiety were evaluated. RESULTS: The mean age of the patients (38 males and 22 females) was (52 ± 12) years. APE patients displayed higher scores of depression (P = 0.04) and anxiety (P = 0.001) compared with controls. Patients in the high-risk group displayed higher scores of depression (P = 0.004) and anxiety (P = 0.001) compared with those in the intermediate- and low-risk groups. Depression scores were highly correlated with anxiety scores (r = 0.60, P < 0.001). Both depression and anxiety inversely related to risk stratification (P < 0.01), age (P < 0.05), and arterial blood oxygen pressure (PaO2) (P < 0.05). Linear regression analysis showed that PaO2 was independently inversely related to both depression (P < 0.01) and anxiety (P < 0.05); risk stratification and age were independently inversely related to anxiety (P < 0.05). CONCLUSIONS: Patients of APE suffered high levels of depression and anxiety, which were negatively influenced by PaO2, risk stratification and age.