Damage to endothelial barriers and its contribution to long COVID.

The world continues to contend with COVID-19, fueled by the emergence of viral variants. At the same time, a subset of convalescent individuals continues to experience persistent and prolonged sequelae, known as long COVID. Clinical, autopsy, animal and in vitro studies all reveal endothelial injury in acute COVID-19 and convalescent patients. Endothelial dysfunction is now recognized as a central factor in COVID-19 progression and long COVID development. Different organs contain different types of endothelia, each with specific features, forming different endothelial barriers and executing different physiological functions. Endothelial injury results in contraction of cell margins (increased permeability), shedding of glycocalyx, extension of phosphatidylserine-rich filopods, and barrier damage. During acute SARS-CoV-2 infection, damaged endothelial cells promote diffuse microthrombi and destroy the endothelial (including blood-air, blood-brain, glomerular filtration and intestinal-blood) barriers, leading to multiple organ dysfunction. During the convalescence period, a subset of patients is unable to fully recover due to persistent endothelial dysfunction, contributing to long COVID. There is still an important knowledge gap between endothelial barrier damage in different organs and COVID-19 sequelae. In this article, we mainly focus on these endothelial barriers and their contribution to long COVID.

Neutrophil extracellular traps contribute to tissue plasminogen activator resistance in acute ischemic stroke.

Circulating neutrophil extracellular traps (NETs) resistant to t-PA have not been studied completely although NETs in thrombi may contribute to tissue plasminogen activator (t-PA) resistance. This research intended to elucidate whether circulating NETs are associated with t-PA resistance and the underlying mechanism. The levels of NETs were detected in the circulating neutrophils, ischemic brain tissue of acute ischemic stroke (AIS) patients, and transient middle cerebral artery occlusion (tMCAO) models. NET formation in blood, thrombi, and ischemic brain tissue of mice were analyzed by immunofluorescence. Exposed phosphatidylserine (PS) was assessed using flow cytometry and confocal microscopy. Procoagulant activity (PCA) was evaluated using fibrin formation assays, thrombin, and purified coagulation complex. The plasma levels of NETs in AIS patients were significantly higher than those in healthy individuals. After thrombolysis, a significant increase was noted in NET markers in no-improvement patients, while the changes in improvement patients were not significant. Importantly, NETs were decorated with von Willebrand factor (vWF) and plasminogen activator inhibitor-1 (PAI-1) in the blood and thrombi, which could reverse the fibrinolytic effects. In addition, NETs activated platelets (PLTs) and endothelial cells (ECs), stimulating a procoagulant phenotype and facilitating vWF and PAI-1 release. DNase I, activated protein C (APC), and sivelestat markedly inhibited these effects. Furthermore, targeting NETs protected mice from tMCAO-induced cerebral ischemia, possibly by regulating vWF and PAI-1. In summary, NETs may contribute to t-PA resistance in AIS through activation of PLTs and ECs. Strategies against NETs may present a promising therapeutic approach to improve the thrombolysis efficiency of t-PA in AIS patients.

Low level of complement factor H increases the risk of cancer-related death in patients with small-cell lung cancer.

INTRODUCTION: Pulmonary cancer is a kind of deeply invasive tumour which is difficult to treat, and its mortality rate is high. Previous research has shown that activation of complement could contribute to the progression of non-small-cell lung cancer (SCLC). However, little research has been done on SCLC. METHODS: Complement factor H (CFH), complements C3 as well as C4 were measured in patients, and the prognostic impact of different parameters was assessed by log-rank function analysis and Cox multifactor models. Besides, we constructed a predictive model based on complement fractions and validated the accuracy of the model. RESULTS: Among these 242 patients, 200 (82.6%) died. The median survival time was 18.3 months. We found by multifactorial analysis that high levels of CFH decreased the risk of death (HR 0.23, 95% CI 0.10 to 0.57, p<0.001), while elevated complement C4 displayed poor prognosis (HR 2.28, 95% CI 1.66 to 3.13, p<0.001). We screened variables by Cox models and constructed CFH-based prediction models to plot a nomogram by internal validation. The nomogram showed excellent accuracy in assessing the probability of death, yielding an adjusted C-statistics of 0.905. CONCLUSIONS: CFH can be recognised as a biomarker to predict the risk of death in SCLC. The prediction model established based on CFH, C3 and C4 levels has good accuracy in patients' prognostic assessment.

Production of purple Ma bamboo (Dendrocalamus latiflorus Munro) with enhanced drought and cold stress tolerance by engineering anthocyanin biosynthesis.

MAIN CONCLUSION: Overexpression of the leaf color (Lc) gene in Ma bamboo substantially increased the accumulation level of anthocyanin, and improved plant tolerance to cold and drought stresses, probably due to the increased antioxidant capacity. Most bamboos, including Ma bamboo (Dendrocalamus latiflorus Munro), are naturally evergreen and sensitive to cold and drought stresses, while it's nearly impossible to make improvements through conventual breeding due to their long and irregular flowering habit. Moreover, few studies have reported bamboo germplasm innovation through genetic engineering as bamboo genetic transformation remains difficult. In this study, we have upregulated anthocyanin biosynthesis in Ma bamboo, to generate non-green Ma bamboo with increased abiotic stress tolerance. By overexpressing the maize Lc gene, a bHLH transcription activator involved in the anthocyanin biosynthesis in Ma bamboo, we generated purple bamboos with increased anthocyanin levels including cyanidin-3-O-rutinoside, peonidin 3-O-rutinoside, and an unknown cyanidin pentaglycoside derivative. The expression levels of 9 anthocyanin biosynthesis genes were up-regulated. Overexpression of the Lc gene improved the plant tolerance to cold and drought stress, probably due to increased antioxidant capacity. The levels of the cold- and drought-related phytohormone jasmonic acid in the transgenic plants were also enhanced, which may also contribute to the plant stress-tolerant phenotypes. High anthocyanin accumulation level did not affect plant growth. Transcriptomic analysis showed higher expressions of genes involved in the flavonoid pathway in Lc transgenic bamboos compared with those in wild-type ones. The anthocyanin-rich bamboos generated here provide an example of ornamental and multiple agronomic trait improvements by genetic engineering in this important grass species.

LncRNA MEG3 contributes to adenosine-induced cytotoxicity in hepatoma HepG2 cells by downregulated ILF3 and autophagy inhibition via regulation PI3K-AKT-mTOR and beclin-1 signaling pathway.

Adenosine is a promising cytotoxic reagent for tumors, long noncoding RNA (lncRNA) maternally expressed gene 3 (MEG3) has been indicated to play critical roles in tumorigenesis, ILF3 has been recognized as a MEG3-binding protein, however, the roles of adenosine and MEG3 on hepatoma are still ambiguous. To clarify the effects of MEG3 on the adenosine-induced cytotoxicity in hepatoma, MEG3 and ILF3 lentivirus were transduced into human hepatoma HepG2 cells to stimulate overexpression of MEG3 (OE MEG3) and overexpression of ILF3 (OE ILF3), furthermore, ILF3 small interfering RNA (siRNA) was also applied to downregulate the expression of ILF3. In this study, autophagy was markedly inhibited by low concentration of adenosine, which present by not only inhibited transformation from LC3-I to LC3-II and autophagosomes formation, but also the elevation of mTOR and reduction of beclin-1 proteins. Furthermore, low concentration of adenosine also exerted marked cytotoxicity representing induced cell apoptosis together with reductions of cell viability and migration, which were also markedly enhanced by OE MEG3. Novelly and excitingly, adenosine markedly stimulated MEG3 expression, OE MEG3 markedly decreased the ILF3 expression in HepG2 cells, and the adenosine-induced autophagy inhibition, together with the ratio of p-PI3K/PI3K, p-AKT/AKT, and p-mTOR/mTOR were also boosted by OE MEG3. More interestingly, OE ILF3 increased autophagy, whereas downregulated ILF3, especially in the case of adenosine, led to marked autophagy inhibition by decreasing beclin-1. The present study demonstrates autophagy inhibition is involved in the adenosine-induced cytotoxicity in HepG2 cells, the cytotoxicity can be synergized by OE MEG3 via downregulated ILF3 to activate PI3K/Akt/mTOR and inactivate the beclin-1 signaling pathway. In conclusion, MEG3 and inhibition of autophagy might be potential targets for augmenting adenosine-induced cytotoxicity in hepatoma.

Ebola Virus Aptamers: From Highly Efficient Selection to Application on Magnetism-Controlled Chips.

Aptamers for Ebola virus (EBOV) offer a powerful means for prevention and diagnostics. Unfortunately, few aptamers for EBOV have been discovered yet. Herein, assisted by magnetism-controlled selection chips to strictly manipulate selection conditions, a highly efficient aptamer selection platform for EBOV is proposed. With highly stringent selection conditions of rigorous washing, manipulation of minuscule amounts of magnetic beads, and real-time evaluation of the selection effectiveness, the selection performance of the platform was improved significantly. In only three rounds of selection, the high-performance aptamers for EBOV GP and NP proteins were obtained simultaneously, with dissociation constants ( Kd) in the nanomolar range. The aptamer was further applied to the detection of EBOV successfully, with a detection limit of 4.2 ng/mL. The whole detection process that consisted of sample mixing, separation, and signal acquisition was highly integrated and conducted in a magnetism-controlled detection chip, showing high biosafety and great potential for point-of-care detection. The method may open up new avenues for prevention and control of EBOV.

Genome-wide analysis and transcriptomic profiling of the auxin biosynthesis, transport and signaling family genes in moso bamboo (Phyllostachys heterocycla).

BACKGROUND: Auxin is essential for plant growth and development. Although substantial progress has been made in understanding auxin pathways in model plants such as Arabidopsis and rice, little is known in moso bamboo which is famous for its fast growth resulting from the rapid cell elongation and division. RESULTS: Here we showed that exogenous auxin has strong effects on crown and primary roots. Genes involved in auxin action, including 13 YUCCA (YUC) genes involved in auxin synthesis, 14 PIN-FORMED/PIN-like (PIN/PILS) and 7 AUXIN1/LIKE-AUX1 (AUX1/LAX) members involved in auxin transport, 10 auxin receptors (AFB) involved in auxin perception, 43 auxin/indole-3-aceticacid (AUX/IAA) genes, and 41 auxin response factors (ARF) involved in auxin signaling were identified through genome-wide analysis. Phylogenetic analysis of these genes from Arabidopsis, Oryza sativa and bamboo revealed that auxin biosynthesis, transport, and signaling pathways are conserved in these species. A comprehensive study of auxin-responsive genes using RNA sequencing technology was performed, and the results also supported that moso bamboo shared a conserved regulatory mechanism for the expression of auxin pathway genes; meanwhile it harbors its own specific properties. CONCLUSIONS: In summary, we generated an overview of the auxin pathway in bamboo, which provides information for uncovering the precise roles of auxin pathway in this important species in the future.

Enhanced antitumor effects of adenoviral-mediated siRNA against GRP78 gene on adenosine-induced apoptosis in human hepatoma HepG2 cells.

Our previous studies show that adenosine-induced apoptosis is involved in endoplasmic reticulum stress in HepG2 cells. In this study, we have investigated whether knockdown of GRP78 by short hairpin RNA (shRNA) increases the cytotoxic effects of adenosine in HepG2 cells. The adenovirus vector-delivered shRNA targeting GRP78 (Ad-shGRP78) was constructed and transfected into HepG2 cells. RT-PCR assay was used to determine RNA interference efficiency. Effects of knockdown of GRP78 on adenosine-induced cell viabilities, cell-cycle distribution and apoptosis, as well as relative protein expressions were determined by flow cytometry and/or Western blot analysis. The intracellular Ca2+ concentration was detected by laser scanning confocal microscope. Mitochondrial membrane potential (ΔΨm) was measured by a fluorospectrophotometer. The results revealed that GRP78 mRNA was significantly downregulated by Ad-shGRP78 transfection. Knockdown of GRP78 enhanced HepG2 cell sensitivity to adenosine by modulating G0/G1 arrest and stimulating Bax, Bak, m-calpain, caspase-4 and CHOP protein levels. Knockdown of GRP78 worsened cytosolic Ca2+ overload and ΔΨm loss. Knockdown of caspase-4 by shRNA decreased caspase-3 mRNA expression and cell apoptosis. These findings indicate that GRP 78 plays a protective role in ER stress-induced apoptosis and show that the combination of chemotherapy drug and RNA interference adenoviruses provides a new treatment strategy against malignant tumors.

Effects of exercise, metformin, and combination treatments on type 2 diabetic mellitus-induced muscle atrophy in db/db mice: Crosstalk between autophagy and the proteasome.

Both exercise and metformin are common effective clinical treatments of type 2 diabetic mellitus. This study investigated the functional role of exercise, metformin, and combination treatment on type 2 diabetic mellitus-induced muscle atrophy. In this experiment, a total of 10 BKS mice were set as the control group. A total of 40 BKS-db/db mice were randomly divided into the control group (db/db); the exercise intervention group (db/db + Ex), which ran on a treadmill at 7-12 m/min, 30-40 min/day, 5 days/week; the metformin administration group (db/db + Met), which was administered 300 mg/kg of metformin solution by gavage daily; and the exercise combined with metformin administration group (db/db + Ex + Met). After 8 weeks of intervention, their tibialis anterior muscles were removed. The levels of insulin signaling pathway proteins, ubiquitin proteasome, and autophagic lysosome-associated proteins were detected using western blot, the expression of MuRF1 and Atrogin-1 was detected using immunohistochemical staining, and the degradation of autophagosomes was detected using double-labeled immunofluorescence. The db/db mice exhibited reduced insulin sensitivity and inhibition of the autophagic-lysosome system, the ubiquitin-proteasome system was activated, and protein degradation was exacerbated, leading to skeletal muscle atrophy. Exercise and metformin and their combined interventions can increase insulin sensitivity, whereas exercise alone showed more effective in inhibiting the ubiquitin-proteasome system, improving autophagy levels, and alleviating skeletal muscle atrophy. Compared with metformin, exercise demonstrated superior improvement of muscle atrophy by promoting the synthesis and degradation of autophagy through the AMPK/ULK1 pathway. However, the combination treatment exhibits no synergistic effect on muscle atrophy.

SIRPG promotes lung squamous cell carcinoma pathogenesis via M1 macrophages: a multi-omics study integrating data and Mendelian randomization.

Background: Squamous cell carcinoma of the lung (LUSC) is a severe and highly lethal malignant tumor of the respiratory system, and its molecular mechanisms at the molecular level remain unc\lear. Methods: We acquired RNA-seq data from 8 surgical samples obtained from early-stage LUSC and adjacent non-cancerous tissues from 3 different centers. Utilizing Deseq2, we identified 1088 differentially expressed genes with |LogFC| > 1 and a p-value < 0.05 threshold. Furthermore, through MR analysis of Exposure Data for 26,153 Genes and 63,053 LUSC Patients, incorporating 7,838,805 SNPs as endpoints, we identified 213 genes as potential exposure factors. Results: After intersecting the results, we identified 5 differentially expressed genes, including GYPE, PODXL2, RNF182, SIRPG, and WNT7A. PODXL2 (OR 95% CI, 1.169 (1.040 to 1.313)) was identified as an exposed risk factor, with p-values less than 0.01 under the inverse variance weighted model. GO and KEGG analyses revealed enhanced ubiquitin-protein transferase activity and activation of pathways such as the mTOR signaling pathway and Wnt signaling pathway. Immune infiltration analysis showed downregulation of Plasma cells, T cells regulatory (Tregs), and Dendritic cells activated by the identified gene set, while an enhancement was observed in Macrophages M1. Furthermore, we externally validated the expression levels of these five genes using RNA-seq data from TCGA database and 11 GEO datasets of LUSC, and the results showed SIRPG could induce LUSC. Conclusion: SIRPG emerged as a noteworthy exposure risk factor for LUSC. Immune infiltration analysis highlighted Macrophages M1 and mTOR signaling pathway play an important role in LUSC.

The intersection of obesity and (long) COVID-19: Hypoxia, thrombotic inflammation, and vascular endothelial injury.

The role of hypoxia, vascular endothelial injury, and thrombotic inflammation in worsening COVID-19 symptoms has been generally recognized. Damaged vascular endothelium plays a crucial role in forming in situ thrombosis, pulmonary dysfunction, and hypoxemia. Thrombotic inflammation can further aggravate local vascular endothelial injury and affect ventilation and blood flow ratio. According to the results of many studies, obesity is an independent risk factor for a variety of severe respiratory diseases and contributes to high mechanical ventilation rate, high mortality, and slow recovery in COVID-19 patients. This review will explore the mechanisms by which obesity may aggravate the acute phase of COVID-19 and delay long COVID recovery by affecting hypoxia, vascular endothelial injury, and thrombotic inflammation. A systematic search of PubMed database was conducted for papers published since January 2020, using the medical subject headings of "COVID-19" and "long COVID" combined with the following keywords: "obesity," "thrombosis," "endothelial injury," "inflammation," "hypoxia," "treatment," and "anticoagulation." In patients with obesity, the accumulation of central fat restricts the expansion of alveoli, exacerbating the pulmonary dysfunction caused by SARS-CoV-2 invasion, inflammatory damage, and lung edema. Abnormal fat secretion and immune impairment further aggravate the original tissue damage and inflammation diffusion. Obesity weakens baseline vascular endothelium function leading to an early injury and pre-thrombotic state after infection. Enhanced procoagulant activity and microthrombi promote early obstruction of the vascular. Obesity also prolongs the duration of symptoms and increases the risk of sequelae after hospital discharge. Persistent viral presence, long-term inflammation, microclots, and hypoxia may contribute to the development of persistent symptoms, suggesting that patients with obesity are uniquely susceptible to long COVID. Early interventions, including supplemental oxygen, comprehensive antithrombotic therapy, and anti-inflammatory drugs, show effectiveness in many studies in the prevention of serious hypoxia, thromboembolic events, and systemic inflammation, and are therefore recommended to reduce intensive care unit admission, mortality, and sequelae.

Prognostic value of miR-219-5p in relation to mortality in patients with small cell lung cancer: a retrospective, observational cohort study in China.

OBJECTIVES: Small cell lung cancer (SCLC) is a lethal human malignancy, and previous studies support the contribution of microRNA to cancer progression. The prognostic value of miR-219-5p in patients with SCLC remains unclear. This study aimed to evaluate the predictive value of miR-219-5p with respect to mortality in patients with SCLC and to incorporate miR-219-5p level into a prediction model and nomogram for mortality. DESIGN: Retrospective observational cohort study. SETTING AND PARTICIPANTS: Our main cohort included data from 133 patients with SCLC between 1 March 2010 and 1 June 2015 from the Suzhou Xiangcheng People's Hospital. Data from 86 patients with non-SCLC at Sichuan Cancer Hospital and the First Affiliated Hospital of Soochow University were used for external validation. OUTCOME MEASURES: Tissue samples were taken during admission and stored, and miR-219-5p levels were measured at a later date. A Cox proportional hazard model was used for survival analyses and for analysing risk factors to create a nomogram for mortality prediction. The accuracy of the model was evaluated by C-index and calibration curve. RESULTS: Mortality in patients with a high level of miR-219-5p (≥1.50) (n=67) was 74.6%, while mortality in the low-level group (n=66) was 100.0%. Based on univariate analysis, we included significant factors (p<0.05) in a multivariate regression model: patients with high level of miR-219-5p (HR 0.39, 95% CI 0.26-0.59, p<0.001), immunotherapy (HR 0.44, 95% CI 0.23-0.84, p<0.001) and prognostic nutritional index score >47.9 (HR=0.45, 95% CI 0.24-0.83, p=0.01) remained statistically significant factors for improved overall survival. The nomogram had good accuracy in estimating the risk, with a bootstrap-corrected C-index of 0.691. External validation indicated an area under the curve of 0.749 (0.709-0.788). CONCLUSIONS: The miR-219-5p level was associated with a reduced risk of mortality in patients with SCLC. A nomogram incorporating MiR-219-5p level and clinical factors demonstrated good accuracy in estimating the risk of overall mortality. Prospective validation of the prognostic nomogram is needed.

Microparticle Phosphatidylserine Mediates Coagulation: Involvement in Tumor Progression and Metastasis.

Tumor progression and cancer metastasis has been linked to the release of microparticles (MPs), which are shed upon cell activation or apoptosis and display parental cell antigens, phospholipids such as phosphatidylserine (PS), and nucleic acids on their external surfaces. In this review, we highlight the biogenesis of MPs as well as the pathophysiological processes of PS externalization and its involvement in coagulation activation. We review the available evidence, suggesting that coagulation factors (mainly tissue factor, thrombin, and fibrin) assist in multiple steps of tumor dissemination, including epithelial-mesenchymal transition, extracellular matrix remodeling, immune escape, and tumor angiogenesis to support the formation of the pre-metastatic niche. Platelets are not just bystander cells in circulation but are functional players in primary tumor growth and metastasis. Tumor-induced platelet aggregation protects circulating tumor cells (CTCs) from the blood flow shear forces and immune cell attack while also promoting the binding of CTCs to endothelial cells and extravasation, which activates tumor invasion and sustains metastasis. Finally, in terms of therapy, lactadherin can inhibit coagulation by competing effectively with coagulation factors for PS binding sites and may similarly delay tumor progression. Furthermore, we also investigate the therapeutic potential of coagulation factor inhibitors within the context of cancer treatment. The development of multiple therapies targeting platelet activation and platelet-tumor cell interactions may not only reduce the lethal consequences of thrombosis but also impede tumor growth and spread.

The combination of exercise and metformin inhibits TGF-ß1/Smad pathway to attenuate myocardial fibrosis in db/db mice by reducing NF-κB-mediated inflammatory response.

Persistent hyperglycemia increases inflammation response, promoting the development of myocardial fibrosis. Based on our previous research that exercise and metformin alone or their combination intervention could attenuate myocardial fibrosis in db/db mice, this study aimed to further explore the underlying mechanisms by which these interventions attenuate myocardial fibrosis in early diabetic cardiomyopathy. Forty BKS db/db mice were randomly divided into four groups. Diabetic db/db mice without intervention were in the C group. Aerobic exercise (7-12 m/min, 30-40 min/day, 5 days/week) was performed in the E group. Metformin (300 mg·kg-1·day-1) was administered in the M group. Exercise combined with metformin was performed in the EM group. Ten wild-type mice were in the WT group. All interventions were administered for 8 weeks. Results showed that the expression levels of α-SMA, Collagen I, and Collagen III were increased in 16-week-old db/db mice, which were reversed by exercise and metformin alone or their combination intervention. All interventions attenuated the level of TGF-ß1/Smad2/3 pathway-related proteins and reduced the expression of inflammatory signaling pathway-regulated proteins TNF-α, p-IκBα/IκBα, and p-NF-κB p65/NF-κB p65 in db/db mice. Furthermore, metformin intervention inhibited HNF4α expression via AMPK activation, whereas exercise intervention increased the expression of IL-6 instead of activating AMPK. In conclusion, exercise and metformin alone or their combination intervention inhibited the TGF-ß1/Smad pathway to attenuate myocardial fibrosis by reducing NF-κB-mediated inflammatory response. The anti-fibrotic effects were regulated by metformin-activated AMPK or exercise-induced elevation of IL-6, whereas their combination intervention showed no synergistic effects.

Decreased complement 4d increases poor prognosis in patients with non-small cell lung cancer combined with gastrointestinal lymph node metastasis.

Lung cancer is a common malignancy that is difficult to treat and has a high risk of mortality. Although gastrointestinal lymph node metastasis has long been known to exert major impact on the prognosis of lung cancer, the mechanism of its occurrence and potential biological markers remain elusive. Therefore, the present study retrospectively analyzed data from 132 patients with non-small cell lung cancer (NSCLC) combined with lymph node metastasis between February 2010 and April 2019 from the First Affiliated Hospital of Soochow University (Suzhou, China) and Sichuan Cancer Hospital (Chengdu, China). Overall survival was assessed using Kaplan-Meier analysis and Cox logistic regression model. In addition, a prediction model was constructed based on immune indicators such as complement C3b and C4d (measured by ELISA), before the accuracy of this model was validated using calibration curves for 5-year OS. Among the 132 included patients, a total of 92 (70.0%) succumbed to the disease within 5 years. Multifactorial analysis revealed that complement C3b deficiency increased the risk of mortality by nearly two-fold [hazard ratio (HR)=2.23; 95% CI=1.20-4.14; P=0.017], whilst complement C4d deficiency similarly increased the risk of mortality by two-fold (HR=2.14; 95% CI=1.14-4.00; P=0.012). The variables were subsequently screened using Cox model to construct a prediction model based on complement C3b and C4d levels before a Nomogram plotted. By internal validation for the 132 patients, the Nomogram accurately estimated the risk of mortality, with a corrected C-index of 0.810. External validation of the model in another 50 patients from Sichuan Cancer Hospital revealed an accuracy of 77.0%. Overall, this mortality risk prediction model constructed based on complement levels showed accuracy in assessing the prognosis of patients with metastatic NSCLC. Therefore, complement C3b and C4d have potential for use as biomarkers to predict the risk of mortality in such patients.

Persistent Lung Injury and Prothrombotic State in Long COVID.

Lung injury may persist during the recovery period of COVID-19 as shown through imaging, six-minute walk, and lung function tests. The pathophysiological mechanisms leading to long COVID have not been adequately explained. Our aim is to investigate the basis of pulmonary susceptibility during sequelae and the possibility that prothrombotic states may influence long-term pulmonary symptoms of COVID-19. The patient's lungs remain vulnerable during the recovery stage due to persistent shedding of the virus, the inflammatory environment, the prothrombotic state, and injury and subsequent repair of the blood-air barrier. The transformation of inflammation to proliferation and fibrosis, hypoxia-involved vascular remodeling, vascular endothelial cell damage, phosphatidylserine-involved hypercoagulability, and continuous changes in serological markers all contribute to post-discharge lung injury. Considering the important role of microthrombus and arteriovenous thrombus in the process of pulmonary functional lesions to organic lesions, we further study the possibility that prothrombotic states, including pulmonary vascular endothelial cell activation and hypercoagulability, may affect long-term pulmonary symptoms in long COVID. Early use of combined anticoagulant and antiplatelet therapy is a promising approach to reduce the incidence of pulmonary sequelae. Essentially, early treatment can block the occurrence of thrombotic events. Because impeded pulmonary circulation causes large pressure imbalances over the alveolar membrane leading to the infiltration of plasma into the alveolar cavity, inhibition of thrombotic events can prevent pulmonary hypertension, formation of lung hyaline membranes, and lung consolidation.

The cross-talk of lung and heart complications in COVID-19: Endothelial cells dysfunction, thrombosis, and treatment.

The pandemic respiratory illness SARS-CoV-2 has increasingly been shown to be a systemic disease that can also have profound impacts on the cardiovascular system. Although associated cardiopulmonary sequelae can persist after infection, the link between viral infection and these complications remains unclear. There is now a recognized link between endothelial cell dysfunction and thrombosis. Its role in stimulating platelet activation and thrombotic inflammation has been widely reported. However, the procoagulant role of microparticles (MPs) in COVID-19 seems to have been neglected. As membrane vesicles released after cell injury or apoptosis, MPs exert procoagulant activity mainly by exposing phosphatidylserine (PS) on their lipid membranes. It can provide a catalytic surface for the assembly of the prothrombinase complex. Therefore, inhibiting PS externalization is a potential therapeutic strategy. In this paper, we describe the pathophysiological mechanism by which SARS-CoV-2 induces lung and heart complications through injury of endothelial cells, emphasizing the procoagulant effect of MPs and PS, and demonstrate the importance of early antithrombotic therapy. In addition, we will detail the mechanisms underlying hypoxia, another serious pulmonary complication related to SARS-CoV-2-induced endothelial cells injury and discuss the use of oxygen therapy. In the case of SARS-CoV-2 infection, virus invades endothelial cells through direct infection, hypoxia, imbalance of the RAAS, and cytokine storm. These factors cause endothelial cells to release MPs, form MPs storm, and eventually lead to thrombosis. This, in turn, accelerates hypoxia and cytokine storms, forming a positive feedback loop. Given the important role of thrombosis in the disease, early antithrombotic therapy is an important tool for COVID-19. It may maintain normal blood circulation, accelerating the clearance of viruses, waning the formation of MPs storm, and avoiding disease progression.

Pathophysiological mechanisms of thrombosis in acute and long COVID-19.

COVID-19 patients have a high incidence of thrombosis, and thromboembolic complications are associated with severe COVID-19 and high mortality. COVID-19 disease is associated with a hyper-inflammatory response (cytokine storm) mediated by the immune system. However, the role of the inflammatory response in thrombosis remains incompletely understood. In this review, we investigate the crosstalk between inflammation and thrombosis in the context of COVID-19, focusing on the contributions of inflammation to the pathogenesis of thrombosis, and propose combined use of anti-inflammatory and anticoagulant therapeutics. Under inflammatory conditions, the interactions between neutrophils and platelets, platelet activation, monocyte tissue factor expression, microparticle release, and phosphatidylserine (PS) externalization as well as complement activation are collectively involved in immune-thrombosis. Inflammation results in the activation and apoptosis of blood cells, leading to microparticle release and PS externalization on blood cells and microparticles, which significantly enhances the catalytic efficiency of the tenase and prothrombinase complexes, and promotes thrombin-mediated fibrin generation and local blood clot formation. Given the risk of thrombosis in the COVID-19, the importance of antithrombotic therapies has been generally recognized, but certain deficiencies and treatment gaps in remain. Antiplatelet drugs are not in combination with anticoagulant treatments, thus fail to dampen platelet procoagulant activity. Current treatments also do not propose an optimal time for anticoagulation. The efficacy of anticoagulant treatments depends on the time of therapy initiation. The best time for antithrombotic therapy is as early as possible after diagnosis, ideally in the early stage of the disease. We also elaborate on the possible mechanisms of long COVID thromboembolic complications, including persistent inflammation, endothelial injury and dysfunction, and coagulation abnormalities. The above-mentioned contents provide therapeutic strategies for COVID-19 patients and further improve patient outcomes.

Low serum albumin levels and high neutrophil counts are predictive of a poorer prognosis in patients with metastatic breast cancer.

Breast cancer is a severe disease with high incidence and mortality rates in menopausal women. Previous studies have shown that nutritional status and inflammation play a significant role in the development of breast cancer. However, whether serum albumin (ALB) and neutrophils (NE) accelerate the progression of this disease remains unclear. In the present study, a total of 94 cases of newly diagnosed metastatic breast cancer were assessed. For analysis, 26 risk factors including ALB and NE were assessed. Multivariate Cox proportional hazards regression analysis was then used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) after adjusting for continuous and categorical covariates. Compared with the control group, patients with disease progression, low levels of ALB, higher NE, counts, and higher neutrophil to lymphocyte ratio counts were associated with worse overall survival (OS). When these risk factors were fitted into a multivariate regression model, progression [P<0.001, HR=3.03 (1.62-5.66)], NE counts ≥3.370×109 [P=0.004, HR=2.15 (1.27-3.65)] and ALB levels <43.275 g/l [P=0.008, HR=0.47 (0.27-0.82)] remained statistically significant factors for a worse OS. These independently associated risk factors were used to form an OS estimation nomogram. The constructed nomogram demonstrated good accuracy in estimating risk, with a bootstrap-corrected C index of 0.686. We further collected data on 30 patients for external validation and found the nomogram had an accuracy of 83.3%. In conclusion, low serum ALB levels and increased NE counts were predictive of a poorer prognosis in patients with metastatic breast cancer. Nomograms based on the multivariate analysis showed a good predictive ability for estimating the risk of OS.

Circulating D-Dimers Increase the Risk of Mortality and Venous Thromboembolism in Patients With Lung Cancer: A Systematic Analysis Combined With External Validation.

Background: D-dimer is a fibrin-degrading substance that is soluble and whose degradation is produced by plasma protein-mediated degradation of cross-linked fibrin. Previous investigations have shown a link between D-dimer and the mortality in lung cancer patients. However, different investigations varied whether D-dimer could predict prognosis in these patients. Methods: A meta-analysis and systematic review of all available cohort studies were performed on the link between circulating D-dimer levels and survival of lung cancer patients. Relevant studies were searched in Embase, Cochrane Library, and PubMed databases. Data from 540 lung cancer patients from the First Hospital of Soochow University and Sichuan Cancer Hospital were used for external validation. Results: We finally obtained 19 eligible cohort studies with pooled HR showing that high D-dimer levels contribute to death in tumor group (HR 1.62, 95% CI: 1.39-1.88, I2 = 75.0%). Further stratified analysis showed that higher circulating D-dimer in the advanced lung cancer group was linked to a 1.91-fold risk (HR = 2.91, 95% CI: 2.24-3.78, I2 = 6.0%). Incorporation of other variables, including days of follow-up, country, design, public year, population, disease status, and quality score, into the meta-regression model, indicated that disease status was an additional source of heterogeneity (p < 0.001). External validation of 540 patients also showed that high levels of D-dimer showed a higher risk of overall mortality (HR 1.39, 95% CI: 1.13-1.72, p = 0.002) and VTE events (HR 3.98, 95% CI: 1.99-8.70, p = 0.002) in lung cancer patients. Conclusions: High circulating plasma D-dimer levels independently predict long-term prognosis and the risk of venous thromboembolism in lung cancer.