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Currently, pulsed adders are used as pulsed voltage sources maturely. However, their use as pulsed current sources is significantly limited due to circuit impedance and the characteristics of power devices. This paper presents a simple yet effective design for a pulsed current source, incorporating a solid-state Marx pulsed adder as the primary power source and an inductor for energy storage. In the pulsed current source, a Marx pulsed adder produces high voltage to charge the inductor. Then, the stored inductance energy is converted to generate current pulses on the load; the amplitude of the pulsed current is unaffected by the load impedance within a certain range. The pulsed current source can be designed as a standard module, and several modules can form a cascade system for producing current pulses with higher voltage. Finally, a pulsed current source was developed, which can produce adjustable current pulses with high voltage. The design principles, control methods and the effects of the distribution parameters are described. The feasibility of the cascade pulsed power system was validated in experiments. Nine modules were connected to generate pulses of current 10 A on a 15 kΩ resistor. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI) and resultant acute respiratory distress syndrome (ARDS) are detrimental inflammatory disease associated with high rates of morbidity and mortality due to a lack of effective treatment options. Previous study has demonstrated that an inhibition of geranylgeranyl pyrophosphate synthase large subunit 1 (GGPPS1) show a protective effect against ALI. In this study, by using connective map (CMAP), we identified catechin as a potential drug to exhibit similar effects to inhibit GGPPS1. Furthermore, we detected the protective effect of catechin on lipopolysaccharide (LPS)-induced ALI and delineated the underlying mechanism. We found that catechin effectively ameliorated LPS-induced lung inflammation and alleviated the release of cytokines into alveolar space. Notably, miR-182/GGPPS1 signaling pathway was reactivated upon catechin administration, which was essential for the catechin-induced protective effect against ALI. catechin regulates miR-182/GGPPS1 signaling pathway and efficaciously ameliorates LPS-induced acute lung injury in mice model, which provided a promising therapeutic strategy in ALI and ARDS. [ABSTRACT FROM AUTHOR]

Introduction: Chronic obstructive pulmonary disease (COPD) is associated with poor prognosis in non‐small cell lung cancer (NSCLC) patients. There are limited data about the impact of severe‐to‐very severe COPD on prognosis in patients with NSCLC receiving first‐line chemotherapy. Objectives: To investigate whether severe‐to‐very severe COPD impacted survival of patients with NSCLC receiving first‐line chemotherapy. Methods: A retrospective review was performed on 513 consecutive NSCLC patients receiving first‐line chemotherapy between February 2014 and May 2018. Prognostic impact of severe‐to‐very severe COPD was analysed using regression analyses. Results: Totally 258 NSCLC patients (118 non‐COPD, 96 mild‐to‐moderate COPD and 44 severe‐to‐very severe COPD) were evaluated retrospectively. Kaplan‐Meier analysis showed that the median overall survival times in the severe‐to‐very severe COPD, mild‐to‐moderate COPD and non‐COPD groups were 14.0 months [95% confidence interval (CI): 11.0‐17.0], 18 months (95% CI: 14.8‐21.2) and 19 months (95% CI: 15.3‐22.7), respectively. The difference was significant between patients with severe‐to‐very severe COPD and those without COPD (χ2 = 6.8, P = 0.009) and between patients with severe‐to‐very severe COPD and those with mild‐to‐moderate COPD (χ2 = 4.0, P = 0.045). Multivariate analysis showed that survival time was significantly shorter in the severe‐to‐very severe COPD group than in the non‐COPD group (adjusted hazard ratio: 1.876, 95% CI: 1.161‐3.030, P = 0.01) and mild‐to‐moderate COPD group (adjusted hazard ratio: 1.782, 95% CI: 1.046‐3.034, P = 0.033). Conclusion: Severe‐to‐very severe COPD may worsen the prognosis of NSCLC patients who received first‐line chemotherapy. [ABSTRACT FROM AUTHOR]

Marx generator using all-solid-state devices has been studied for many years. Higher parameters are always the demand for new applications. Traditional all-solid-state Marx generator can output high voltage due to its series topology, but the current is always limited by the switch. In this paper, a stage-stage paralleled topology of Marx generator for high current has been proposed. Topology structure and driving mode comparison for current balance have been analyzed. The paralleled driving mode for the current balance and the shaping waveform has been proposed. For experiment, a four-stage-four-paralleled Marx generator with metal–oxide–semiconductor field-effect transistors (MOSFETs) has been constructed with output pulses 2.2 kV, 730 A (depending on the load), rise time of 31 ns, fall time of 56 ns, and adjustable pulsewidth from 400 to 800 ns. [ABSTRACT FROM AUTHOR]

Introduction: Chronic obstructive pulmonary disease (COPD) is associated with risk of venous thromboembolism (VTE) events. A detailed understanding of which clinical features of COPD increase risk of VTE events is needed. Objectives: To investigate the association between features of COPD and risk of venous thromboembolism. Methods: A retrospective observational clinical study was conducted on 551 consecutive COPD patients visiting the Department of Respiratory and Critical Care Medicine of Tianjin Chest Hospital between February 2014 and April 2018. Finally, 151 patients were eligible for inclusion. Of these, 29 patients had COPD with VTE and 121 patients had COPD without VTE. Patient informations regarding age, gender, BMI, smoking history, smoking status (package/year), COPD‐related symptoms, lung function, number of acute exacerbations and imaging visual emphysema were gathered. Results: Among the 29 VTE patients, 18 patients had PE and five had DVT, while 6 patients had simultaneous PE and DVT. There were statistically significant differences in GOLD grade, Imaging visual emphysema, and frequent acute exacerbations between the two groups. Multivariate logistic regression analysis showed that after adjustment for gender, age, BMI and smoking history, there were statistically significant for visible emphysema (OR = 3.54, 95% CI: 1.13‐11.08; P = 0.03) and GOLD grade (OR = 1.77, 95% CI: 1.04‐3.01; P = 0.035), but not for frequent acute exacerbations (OR = 1.65, 95% CI: 0.62‐4.38; P = 0.31). Conclusions: Visual emphysema is an independent risk factor for VTE events and the risk of VTE in COPD patients increases with the degree of airway obstruction. However, there is no evidence of an association between exacerbation frequency and VTE events. [ABSTRACT FROM AUTHOR]

Background: The first-line standard treatment option for patients with NSCLC complicated with Chronic obstructive pulmonary disease (COPD) is still unclear and relies on the treatment option of NSCLC alone. To date, a limited number of retrospective studies have explored the efficacy and safety of immunotherapy in patients with NSCLC complicated with COPD. We therefore designed this study to further explore the efficacy and safety of first-line immunotherapy in patients with NSCLC complicated with COPD., Methods: This study was designed as a single-armed, single-center, prospective, phase II clinical study. It will include 30 advanced (stage IV) NSCLC combined with COPD primary treatment subjects. Each subject's diagnosis will be confirmed by clinical, radiographic, pathologic, and pulmonary function evaluation. A fixed dose of 200 mg pembrolizumab will be administered by intravenous infusion on day1 every 3 weeks (Q3W). The management of stable and acute exacerbations of COPD include home oxygen therapy, and the use of conventional medications are also administered. Imaging evaluation will be performed every 6 weeks for 6 months from the first pembrolizumab dose and approximately every 12 weeks thereafter until disease progression or early withdrawal. COPD status will be evaluated every 3 months by pulmonary function, GOLD grading, mMRC score, CAT score, ABCD grouping, and AECOPD severity. The primary outcome is Progression-free survival. The secondary outcome measures include objective response rate, overall survival, rate of acute exacerbations of COPD (times/year), lung function, mMRC score, CAT score, impact of treatment on patient's health-related quality of life, antibiotic use (including duration and classes), and adverse events associated with immune checkpoint inhibitors. Exploratory endpoint is to explore the association between COPD grade and the degree of immune cell (CD4+ T lymphocytes and CD8+ T lymphocytes) infiltration, as well as the association between COPD grade and the efficacy of immune checkpoint inhibitors., Clinical Trial Registration: ClinicalTrials.gov, identifier NCT05578222., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Dong, Yin, Liu, Jiang, Wang, Shi and Qin.)