Regulating the Distribution and Accumulation of Charged Molecules by Progressive Electroporation for Improved Intracellular Delivery.

The cell membrane separates the intracellular compartment from the extracellular environment, constraining exogenous molecules to enter the cell. Conventional electroporation typically employs high-voltage and short-duration pulses to facilitate the transmembrane transport of molecules impermeable to the membrane under natural conditions by creating temporary hydrophilic pores on the membrane. Electroporation not only enables the entry of exogenous molecules but also directs the intracellular distribution of the electric field. Recent advancements have markedly enhanced the efficiency of intracellular molecule delivery, achieved through the utilization of microstructures, microelectrodes, and surface modifications. However, little attention is paid to regulating the motion of molecules during and after passing through the membrane to improve delivery efficiency, resulting in an unsatisfactory delivery efficiency and high dose demand. Here, we proposed the strategy of regulating the motion of charged molecules during the delivery process by progressive electroporation (PEP), utilizing modulated electric fields. Efficient delivery of charged molecules with an expanded distribution and increased accumulation by PEP was demonstrated through numerical simulations and experimental results. The dose demand can be reduced by 10-40% depending on the size and charge of the molecules. We confirmed the safety of PEP for intracellular delivery in both short and long terms through cytotoxicity assays and transcriptome analysis. Overall, this work not only reveals the mechanism and effectiveness of PEP-enhanced intracellular delivery of charged molecules but also suggests the potential integration of field manipulation of molecular motion with surface modification techniques for biomedical applications such as cell engineering and sensitive cellular monitoring.

Assessing the influence of parameters on tissue welding in small bowel end-to-end anastomosis in vitro and in vivo.

BACKGROUND: The use of high-frequency electric welding technology for intestinal end-to-end anastomosis holds significant promise. Past studies have focused on in vitro, and the safety and efficacy of this technology is uncertain, severely limiting the clinical application of this technology. This study investigates the impact of compression pressure, energy dosage, and duration on anastomotic quality using a homemade anastomosis device in both in vitro and in vivo settings. METHODS: Two hundred eighty intestines and 5 experimental pigs were used for in vitro and in vivo experiments, respectively. The in vitro experiments were conducted to study the effects of initial pressure (50-400 kpa), voltage (40-60 V), and time (10-20 s) on burst pressure, breaking strength, thermal damage, and histopathological microstructure of the anastomosis. Optimal parameters were then inlaid into a homemade anastomosis and used for in vivo experiments to study the postoperative porcine survival rate and the pathological structure of the tissues at the anastomosis and the characteristics of the collagen fibers. RESULTS: The anastomotic strength was highest when the compression pressure was 250 kPa, the voltage was 60 V, and the time was 15 s. The degree of thermal damage to the surrounding tissues was the lowest. The experimental pigs had no adverse reactions after the operation, and the survival rate was 100%. 30 days after the operation, the surgical site healed well, and the tissues at the anastomosis changed from immediate adhesions to permanent connections. CONCLUSION: High-frequency electric welding technology has a certain degree of safety and effectiveness. It has the potential to replace the stapler anastomosis in future and become the next generation of new anastomosis device.

Engineering of Multivalent Membrane-Anchored DNA Frameworks for Precise Profiling of Variable Membrane Permeability During Reversible Electroporation.

Electroporation techniques have emerged as attractive tools for intracellular delivery, rendering promising prospects towards clinical therapies. Transient disruption of membrane permeability is the critical process for efficient electroporation-based cargo delivery. However, smart nanotools for precise characterization of transient membrane changes induced by strong electric pulses are extremely limited. Herein, multivalent membrane-anchored fluorescent nanoprobes (MMFNPs) that take advantages of flexible functionalization and spatial arrangement of DNA frameworks are developed for in situ evaluation of electric field-induced membrane permeability during reversible electroporation . Single-molecule fluorescence imaging techniques are adopted to precisely  verify the excellent analytical performance of the engineered MMFNPs. Benefited from tight membrane anchoring and sensitive adenosine triphosphate (ATP) profiling, varying degrees of membrane disturbances are visually exhibited under different intensities of the microsecond pulse electric field (µsPEF). Significantly, the dynamic process of membrane repair during reversible electroporation is well demonstrated via ATP fluctuations monitored by the designed MMFNPs. Furthermore, molecular dynamics (MD) simulations are performed for accurate verification of electroporation-driven dynamic cargo entry via membrane nanopores. This work provides an avenue for effectively capturing transient fluctuations of membrane permeability under external stimuli, offering valuable guidance for developing efficient and safe electroporation-driven delivery strategies for clinical diagnosis and therapeutics.

Glioblastoma behavior study under different frequency electromagnetic field.

The tumor-treating fields (TTFields) technology has revolutionized the management of recurrent and newly diagnosed glioblastoma (GBM) cases. To ameliorate this treatment modality for GBM and other oncological conditions, it is necessary to understand the biophysical principles of TTFields better. In this study, we further analyzed the mechanism of the electromagnetic exposure with varying frequencies and electric field strengths on cells in mitosis, specifically in telophase. In reference to previous studies, an intuitive finite element model of the mitotic cell was built for electromagnetic simulations, predicting a local increase in the cleavage furrow region, which may help explain TTFields' anti-proliferative effects. Cell experiments confirmed that the reduction in proliferation and migration of glioma cell by TTFields was in a frequency- and field-strength-dependent manner. This work provides unique insights into the selection of frequencies in the anti-proliferative effect of TTFields on tumors, which could improve the application of TTFields.

Comparison of COVID-19 and influenza characteristics.

The emergence of coronavirus disease 2019 (COVID-19) not only poses a serious threat to the health of people worldwide but also affects the global economy. The outbreak of COVID-19 began in December 2019, at the same time as the influenza season. However, as the treatments and prognoses of COVID-19 and influenza are different, it is important to accurately differentiate these two different respiratory tract infections on the basis of their respective early-stage characteristics. We reviewed official documents and news released by the National Health Commission of the People's Republic of China, the Chinese Center for Disease Control and Prevention (China CDC), the United States CDC, and the World Health Organization (WHO), and we also searched the PubMed, Web of Science, Excerpta Medica database (Embase), China National Knowledge Infrastructure (CNKI), Wanfang, preprinted bioRxiv and medRxiv databases for documents and guidelines from earliest available date up until October 3rd, 2020. We obtained the latest information about COVID-19 and influenza and summarized and compared their biological characteristics, epidemiology, clinical manifestations, pathological mechanisms, treatments, and prognostic factors. We show that although COVID-19 and influenza are different in many ways, there are numerous similarities; thus, in addition to using nucleic acid-based polymerase chain reaction (PCR) and antibody-based approaches, clinicians and epidemiologists should distinguish between the two using their respective characteristics in early stages. We should utilize experiences from other epidemics to provide additional guidance for the treatment and prevention of COVID-19.

Mean platelet volume combined red cell distribution width as biomarker of chronic obstructive pulmonary disease with pulmonary heart disease.

BACKGROUND AND OBJECTIVE: Platelet activation, inflammatory reactions and oxidative stress are common pathogenesis of chronic obstructive pulmonary disease (COPD) with pulmonary heart disease (PHD). Mean platelet volume (MPV) and red blood cell distribution width (RDW) form part of the pathomechanisms of these conditions. Here, we investigated whether MPV and RDW can be biomarkers of PHD occurring secondary to COPD. MATERIALS AND METHODS: This was a retrospective study on 229 participants with COPD. Among them, 69 had PHD. Complete blood count (CBC), blood gas analysis, pulmonary function tests and echocardiography were analyzed. RESULTS: MPV and RDW-standard deviation (RDW-SD) were significantly higher in patients with PHD than in patients without PHD (P ≤ 0.001). MPV and RDW-SD were positively correlated with pulmonary artery pressure (PAP) and the size of the right ventricle (P ≤ 0.05). Multivariate regression analysis showed that the risk of PHD increased 3-fold per unit rise in MPV (OR = 2.901, P ≤ 0.001). We observed that the risk of PHD increased 1.5 times per unit rise in RDW-SD (OR = 1.371, P ≤ 0.001).The AUC of ROC curve for the combined MPV and RDW-SD in predicting PHD among COPD patients was 0.900 (95％CI: 0.846-0．954, P ≤ 0.001), with a sensitivity of 76.8% and a specificity of 99.4%. CONCLUSIONS: Both MPV and RDW-SD were significantly elevated and correlated with disease severity in COPD patients with PHD. A combination of these two parameters presents an effective biomarker of PHD.

Paroxysmal Laryngospasm: A Rare Condition That Respiratory Physicians Must Distinguish from Other Diseases with a Chief Complaint of Dyspnea.

Background: In recent years, we have observed respiratory difficulty manifested as paroxysmal laryngospasm in a few outpatients, most of whom were first encountered in a respiratory clinic. We therefore explored how to identify and address paroxysmal laryngospasm from the perspective of respiratory physicians. Methods: The symptoms, characteristics, auxiliary examination results, treatment, and prognosis of 12 patients with paroxysmal laryngospasm treated in our hospital from June 2017 to October 2019 were analyzed. Results: Five males (42%) and 7 females (58%) were among the 12 Han patients sampled. The average age of the patients was 49.25 ± 13.02 years. The disease course ranged from 14 days to 8 years and was characterized by sudden dyspnea, an inability to inhale and exhale, a sense of asphyxia, and voice loss during an attack. Eight patients with gastroesophageal reflux were cured after antacid treatment. One case of upper respiratory tract infection (URI) was completely relieved after symptomatic treatment. One patient with left vocal cord paralysis experienced complete relief after specialist treatment by an otorhinolaryngologist. Episodes in 1 patient were significantly reduced after lifestyle improvement. One patient experienced spontaneous relief after rejecting treatment. Conclusions: Paroxysmal laryngospasm is a rare laryngeal disease that generally occurs secondary to gastroesophageal reflux disease (GERD), and antireflux therapy is frequently effective for its treatment. A respiratory physician should master and identify the symptoms and differentiate this condition from hysterical stridor, reflux-related laryngospasm, and asthma. Timely referral to otolaryngologists, gastroenterologists, and other specialists for standardized examination and regular treatment should be provided when necessary.

Interleukin-26 upregulates interleukin-22 production by human CD4+ T cells in tuberculous pleurisy.

IL-26 is a potentially important player in host defense and may be a pathogenic factor in the chronic inflammatory disorders of humans. However, the involvement of IL-26 in tuberculous pleural effusion (TPE) has not been investigated. The concentration of IL-26 was determined in pleural fluids and sera from patients with pleural effusions. Flow cytometry was performed to identify the cell origin of IL-26. The effects of tuberculosis-specific antigen (ESAT-6/CFP-10) on IL-26 expression of CD4+ T cell were explored. The impacts of IL-26 on modulating CD4+ T cell polarization were also investigated. The concentrations of IL-26 were much higher in tuberculous, malignant, and infectious PE than those in the corresponding serum. The expression of IL-26 on CD4+ T cells was much higher in tuberculous PE than those in the corresponding serum, and pleural Th1 and Th17 cells might be the major cell sources of IL-26. The addition of ESAT-6/CFP-10 to CD4+ T cells led to increasing the number of IL-26-producing CD4+ T cells and IL-26 expression on Th1 and Th17 cells. IL-26 could induce the differentiation and generation of IL-22 by memory and naive CD4+ T cells. IL-26 also upregulated the mRNA encoding CC-chemokine ligand 20 (CCL20) and CCL22 by mononuclear cells isolated from TPE. This study implies that pleural Th1 and Th17 cells are the major cell sources of IL-26, which could induce the differentiation and generation of Th22 cells by CD4+ T cells, suggesting the involvement of IL-26 in the pathogenesis of human TPE. KEY MESSAGES: IL-26 is overexpressed in TPE patients and presents a higher concentration in pleural effusion than the corresponding peripheral blood. Pleural Th1 and Th17 cells might be the major cell sources of IL-26 in TPE patients. IL-26 promotes IL-22 secretion and Th22 generation by CD4+ T cells isolated from TPE patients. IL-26 may play an active role in the pathogenesis of tuberculous pleurisy.

Generation and Immune Regulation of CD4+CD25-Foxp3+ T Cells in Chronic Obstructive Pulmonary Disease.

The imbalance of CD4+Foxp3+ T cell subsets is reportedly involved in abnormal inflammatory immune responses in patients with chronic obstructive pulmonary disease (COPD). However, the possible role of CD4+CD25-Foxp3+ T cells in immune regulation in COPD remains to be investigated. In the current study, distribution and phenotypic characteristics of CD4+CD25-Foxp3+ T cells from peripheral blood were determined by flow cytometry; the origin, immune function and ultimate fate of CD4+CD25-Foxp3+ T cells were further explored in vitro. It was observed that circulating CD4+CD25-Foxp3+ T cells were significantly increased in stable COPD patients (SCOPD) and resembled central memory or effector memory T cells. Compared with peripheral CD4+CD25+Foxp3+ T cells, peripheral CD4+CD25-Foxp3+ T cells showed a lower expression of Foxp3, CTLA-4, HELIOS, and TIGIT, but a higher expression of CD127 and KI-67, suggesting that CD4+CD25-Foxp3+ T cells lost the expression of Tregs-associated molecules following the reduction in CD25. Unexpectedly, our study found that transforming growth factor-ß1 (TGFß1) decreased CD25 expression and played a critical role in the generation of CD4+CD25-Foxp3+ T cells from CD4+CD25+Foxp3+ T cells. Phenotypic analysis further revealed that both inducible and peripheral CD4+CD25-Foxp3+ T cells exhibited the features of activated conventional T cells. Importantly, memory CD4+CD25-Foxp3+ T cells facilitated the proliferation and differentiation of naïve CD4+ T cells into Th17 cells in the presence of IL-1ß, IL-6, IL-23, and TGFß1. Finally, a fraction of CD4+CD25-Foxp3+ T cells, exhibiting instability and plasticity, were converted to Th17 cells when subjected to Th17 cell-polarizing condition. Taken together, we propose that TGFß1 is responsible for the generation of CD4+CD25-Foxp3+ T cells, and these cells functionally exert an auxiliary effect on Th17 cells generation and might perpetuate chronic inflammation in COPD.

Autologous tumor cell-derived microparticle-based targeted chemotherapy in lung cancer patients with malignant pleural effusion.

Cell membrane-derived microparticles (MPs), the critical mediators of intercellular communication, have gained much interest for use as natural drug delivery systems. Here, we examined the therapeutic potential of tumor cell-derived MPs (TMPs) in the context of malignant pleural effusion (MPE). TMPs packaging the chemotherapeutic drug methotrexate (TMPs-MTX) markedly restricted MPE growth and provided a survival benefit in MPE models induced by murine Lewis lung carcinoma and colon adenocarcinoma cells. On the basis of the potential benefit and minimal toxicity of TMPs-MTX, we conducted a human study of intrapleural delivery of a single dose of autologous TMPs packaging methotrexate (ATMPs-MTX) to assess their safety, immunogenicity, and clinical activity. We report our findings on 11 advanced lung cancer patients with MPE. We found that manufacturing and infusing ATMPs-MTX were feasible and safe, without evidence of toxic effects of grade 3 or higher. Evaluation of the tumor microenvironment in MPE demonstrated notable reductions in tumor cells and CD163+ macrophages in MPE after ATMP-MTX infusion, which then translated into objective clinical responses. Moreover, ATMP-MTX treatment stimulated CD4+ T cells to release IL-2 and CD8+ cells to release IFN-γ. Our initial experience with ATMPs-MTX in advanced lung cancer with MPE suggests that ATMPs targeting malignant cells and the immunosuppressive microenvironment may be a promising therapeutic platform for treating malignancies.

Cytokine-induced alterations of BAMBI mediate the reciprocal regulation of human Th17/Treg cells in response to cigarette smoke extract.

In CD4+ T helper (Th) cells, transforming growth factor ß (TGF­ß) is indispensable for the induction of both regulatory T (Treg) and interleukin­17­producing effector T helper (Th17) cells. Although BMP and activin membrane­bound inhibitor (BAMBI) is part of a rheostat­like mechanism for the regulation of TGF­ß signalling and autoimmune arthritis in mouse models, the underlying activity of BAMBI on the human Th17/Treg cell axis, particularly during exposure to cigarette smoke, remains to be elucidated. The present study aimed to further characterize BAMBI expression in human CD4+ cells, as well as immune imbalance during activation and cigarette smoke exposure. Results from the present study indicated that exposure to cigarette smoke extract partially suppressed Treg differentiation and promoted Th17 cell generation under stimulation by anti­CD3/28 antibodies and TGF­ß1. Additionally, exposure to cigarette smoke induced an inhibition of phosphorylated­Smad2/Smad3, which may have arisen from a concomitant enhancement of BAMBI expression. In conclusion, human BAMBI may function as a molecular switch to control TGF­ß signalling strength and the Th17/Treg cell balance, which may be used not only as a biomarker but also as a target of new treatment strategies for maintaining immune tolerance and for the treatment of smoking­induced immune disorders.

Multiple pulmonary metastases with halo-sign from malignant mixed Müllerian tumors.

The lungs are one of the most common organs to which cancer metastasizes, but are a location not common for uterine sarcoma. A malignant mixed Müllerian tumor (MMMT) of the uterus is an extremely rare and aggressive sarcoma, characterized by a mixture of epithelial and mesenchymal components. There are few reports regarding the pulmonary metastasis from MMMTs. The present study presents the case of a 58-year-old woman with hemoptysis and post-menopausal vaginal bleeding. The woman was initially diagnosed with invasive aspergillosis based on a chest computed tomography (CT) scan showing multiple pulmonary nodular opacities surrounded by a ground-glass attenuation halo (halo-sign). Diagnostic curettage and a percutaneous CT-guided lung biopsy were conducted for the pathological diagnosis. Finally, the diagnosis was confirmed as MMMT with lung metastasis based on the histopathological examination of cervical canals, uterus and lung specimens, which showed a mixture of carcinomatous and sarcomatous elements, and morphology exhibiting hyperchromatic nuclei and necrosis. Immunohistochemical staining was positive for vimentin, focally positive for p16, and negative for napsin, cytokeratin 7 (CK7), CK20, carcinoembryonic antigen, carbohydrate antigen 125, homeobox protein CDX2 and villin in the lung specimens. This case highlights that pulmonary metastatic tumor from uterine sarcoma can present as halo-sign, which is commonly observed in pulmonary aspergillosis. Therefore, it needs to be considered in the differential diagnosis of such lesions, and pathological confirmation is required.

The ACE2/Angiotensin-(1-7)/Mas Receptor Axis: Pleiotropic Roles in Cancer.

Cancer remains one of the most common causes of death and disability and represents a major economic burden in industrialized nations. The renin-angiotensin system (RAS) has been well-recognized as one of the most important regulators of both normal and pathological physiological processes in the brain, kidney, heart, and blood vessels. The activation of the angiotensin-converting enzyme 2/angiotensin-(1-7)/mitochondrial assembly receptor [ACE2/Ang-(1-7)/MasR] axis, which is one component of the RAS, has recently been identified as a critical component of pulmonary systems, gastric mucosa, and cancer. However, the ability of the ACE2/Ang-(1-7)/MasR axis to suppress or promote cancer has not been fully elucidated. In this review, we focus on recent experimental and clinical studies investigating the basic properties, roles, and mechanisms of ACE2, Ang-(1-7), and the MasR, as well as the axis pathway, to provide insights into possible therapeutic strategies for treating cancer that target the ACE2/Ang-(1-7)/MasR axis.

The Role of Interleukin-17 in Lung Cancer.

Tumour-associated inflammation is a hallmark of malignant carcinomas, and lung cancer is a typical inflammation-associated carcinoma. Interleukin-17 (IL-17) is an important inflammatory cytokine that plays an important role in chronic inflammatory and autoimmune diseases and in inflammation-associated tumours. Numerous studies have shown that IL-17 directly or indirectly promotes tumour angiogenesis and cell proliferation and that it inhibits apoptosis via the activation of inflammatory signalling pathways. Therefore, IL-17 contributes to the metastasis and progression of lung cancer. Research advances with respect to the role of IL-17 in lung cancer will be presented as a review in this paper.

TGF-ß/BAMBI pathway dysfunction contributes to peripheral Th17/Treg imbalance in chronic obstructive pulmonary disease.

BMP and activin membrane-bound inhibitor (BAMBI) is postulated to inhibit or modulate transforming growth factor ß (TGF-ß) signaling. Furthermore, strong upregulation of BAMBI expression following in vitro infection of chronic obstructive pulmonary disease (COPD) lung tissue has been demonstrated. In this study, we investigated whether TGF-ß/BAMBI pathway is associated with COPD. Blood samples were obtained from 27 healthy controls (HC), 24 healthy smokers (HS) and 29 COPD patients. Elevated Th17/Treg ratios, and increased levels of BAMBI protein and mRNA (in plasma and CD4(+) T cells respectively), were observed in COPD compared with HC and HS. BAMBI expression was first observed on human CD4(+) T cells, with a typical membrane-bound pattern. The enhanced plasma BAMBI levels in COPD positively correlated with the increased plasma TGF-ß1 levels and Th17/Treg ratio. Together, an impaired TGF-ß/BAMBI pathway may promote the inflammation leading to Th17/Treg imbalance, which is a new mechanism in smokers who develop COPD.

IL-17 induces EMT via Stat3 in lung adenocarcinoma.

Epithelial-mesenchymal transition (EMT) plays a vital role in lung inflammatory diseases, including lung cancer. However, the role and mechanism of action of the proinflammatory cytokine IL-17 in EMT in lung adenocarcinoma remain unresolved. In our study, we discovered that the expression of N-cadherin, Vimentin, Snail1, Snail2, and Twist1 was positively correlated with IL-17 expression, while E-cadherin expression was negatively correlated with IL-17 expression in human lung adenocarcinoma tissues. Moreover, we confirmed that IL-17 promoted EMT in A549 and Lewis lung carcinoma (LLC) cells in vitro by upregulating N-cadherin, Vimentin, Snail1, Snail2, and Twist1 expression and downregulating E-cadherin expression. Stat3 was activated in IL-17-treated A549 and LLC cells, and Stat3 inhibition or siRNA knockdown notably reduced IL-17-induced EMT in A549 and LLC cells. Thus, IL-17 promotes EMT in lung adenocarcinoma via Stat3 signaling; these observations suggest that targeting IL-17 and EMT are potential novel therapeutic strategies for lung cancer.

In vitro antitumor immune response induced by dendritic cells transduced with human livin α recombinant adenovirus.

Transduction with recombinant, replication-defective adenoviral (rAd) vectors encoding a transgene is an efficient method for gene transfer into human dendritic cells (DCs). Livin is a good candidate for cancer immunotherapy since it is overexpressed in most common human cancers, poorly expressed in most normal adult tissues. Two splicing variants of livin, designated livin α and livin ß, have been identified. In this study, we used human livin α recombinant adenovirus (rAd-hlivin α) to transduced DCs. We found that DCs transduced with rAd-hlivin α (rAd-hlivin α DCs) could effectively induce human livin α specific cytotoxic T lymphocytes (CTL) in vitro against various tumor cell lines.

T-cell lymphoblastic lymphoma presenting with pleural effusion: A case report.

Adult lymphoblastic lymphoma (LBL) is an aggressive form of non-Hodgkin lymphoma occurring in predominantly adolescent and young adult men, accounting for 1% to 2% of all non-Hodgkin's lymphomas. In contrast to B-LBL, T-cell LBL is much more common, accounting for up to 90% of disease in adults. Mediastinal mass, pleural and/or pericardial effusions are the major characteristics of T-LBL. We report an 18-year-old male with a pleural effusion, mediastinal mass, a light pericardial effusion, and a normal hemogram. The cytology of the pleural effusion initially suggested malignancy, but definitive diagnosis was unclear. After a medical thoracoscopy, the partial pleura was picked and immunophenotypic study revealed the following: CD3(+), TdT(+), CD99(+), CD20(-). The patient was finally diagnosed with T-LBL and died only 6 months after that. The case highlight the point that medical thoracoscopy is a safe and accurate diagnostic procedure for pleural diseases, and partial pleura biopsy with immunophenotyping was essential for achieving the correct diagnosis of LBL.

Reactive oxygen species and x-ray disrupted spontaneous [Ca²âº]I oscillation in alveolar macrophages.

Radiation leads to a rapid burst of reactive oxygen species (ROS), which is considered to be one of the major causes of radiation-induced injury. ROS have previously been shown to induce changes in cytosolic Ca²âº ([Ca²âº]i) including [Ca²âº]i oscillation. However, the role of radiation in [Ca²âº]i oscillation is poorly understood. The purpose of this study was to identify the effect of ROS and X ray on [Ca²âº]i oscillation, as well as their role in radiation-induced lung injury. Alveolar macrophages were cultured in the absence and presence of different doses of hydrogen peroxide (H2O2) or exposed to X-ray irradiation with or without pretreatment of diphenyleneiodonium chloride (DPI, an inhibitor of NADPH oxidases) or tetrandrine (TET, a calcium entry blocker) and cytosolic Ca²âº concentration was detected by fluorescent Ca²âº indicator Fura-2. Rat radiation lung injury was induced in vivo by using 40 Gy X ray and DPI or TET was used to prevent radiation-induced lung injury. The results showed that there was spontaneous [Ca²âº]i oscillation in alveolar macrophages under normal conditions, and treatment of H2O2 (100-500 µM) or 2 Gy X ray inhibited the spontaneous [Ca²âº]i oscillation and induced [Ca²âº]i rise. TET abolished H2O2 or X ray induced [Ca²âº]i rise in alveolar macrophages, and attenuated X ray- induced rat alveolitis in vivo. DPI prevented X-ray-induced inhibition of [Ca²âº]i oscillation in alveolar macrophages and prevented X-ray-induced rat alveolitis. Taken together, the data suggest that the disruption of [Ca²âº]i oscillation and induction of [Ca²âº]i rise through ROS is involved in the mechanism of radiation-induced lung injury.