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PI3K/AKT/mTOR signalling contributes to several cardiovascular disorders. The aim of this study was to examine the PI3K/AKT/mTOR pathway in myxomatous mitral valve disease (MMVD). Double‐immunofluorescence examined expression of PI3K and TGF‐β1 in canine valves. Valve interstitial cells (VICs) from healthy or MMVD dogs were isolated and characterized. Healthy quiescent VICs (qVICs) were treated with TGF‐β1 and SC‐79 to induce activated myofibroblast phenotypes (aVICs). Diseased valve‐derived aVICs were treated with PI3K antagonists and expression of RPS6KB1 (encoding p70 S6K) was modulated using siRNA and gene overexpression. SA‐β‐gal and TUNEL staining were used to identify cell senescence and apoptosis, and qPCR and ELISA to examine for senescence‐associated secretory phenotype. Protein immunoblotting was used to examine expression of phosphorylated and total proteins. TGF‐β1 and PI3K are highly expressed in mitral valve tissues. Activation of PI3K/AKT/mTOR and increased expression of TGF‐β are found in aVICs. TGF‐β transitions qVICs to aVICs by upregulation of PI3K/AKT/mTOR. Antagonism of PI3K/AKT/mTOR reverses aVIC myofibroblast transition by inhibiting senescence and promoting autophagy. Upregulation of mTOR/S6K induces transformation of senescent aVICs, with reduced capacity for apoptosis and autophagy. Selective knockdown of p70 S6K reverses cell transition by attenuating cell senescence, inhibiting apoptosis and improving autophagy. TGF‐β‐induced PI3K/AKT/mTOR signalling contributes to MMVD pathogenesis and plays crucial roles in the regulation of myofibroblast differentiation, apoptosis, autophagy and senescence in MMVD. [ABSTRACT FROM AUTHOR]

Hemophilia B (HB) is an X-linked recessive disease caused by F9 gene mutation and functional coagulation factor IX (FIX) deficiency. Patients suffer from chronic arthritis and death threats owing to excessive bleeding. Compared with traditional treatments, gene therapy for HB has obvious advantages, especially when the hyperactive FIX mutant (FIX-Padua) is used. However, the mechanism by which FIX-Padua works remains ambiguous due to a lack of research models. Here, in situ introduction of F9-Padua mutation was performed in human induced pluripotent stem cells (hiPSCs) via CRISPR/Cas9 and single-stranded oligodeoxynucleotides (ssODNs). The hyperactivity of FIX-Padua was confirmed to be 364% of the normal level in edited hiPSCs-derived hepatocytes, providing a reliable model for exploring the mechanism of the hyperactivity of FIX-Padua. Moreover, the F9 cDNA containing F9-Padua was integrated before the F9 initiation codon by CRISPR/Cas9 in iPSCs from an HB patient (HB-hiPSCs). Integrated HB-hiPSCs after off-target screening were differentiated into hepatocytes. The FIX activity in the supernatant of integrated hepatocytes showed a 4.2-fold increase and reached 63.64% of the normal level, suggesting a universal treatment for HB patients with various mutations in F9 exons. Overall, our study provides new approaches for the exploration and development of cell-based gene therapy for HB. [ABSTRACT FROM AUTHOR]

Fowl cholera is a serious, highly contagious disease caused by the bacterium Pasteurella multocida (P. multocida) in a range of avian species and is characterized by an acute form of septicaemia. The pathogenic mechanism of chicken lung injury caused by the bacterium is unclear. Therefore, P. multocida Q (a reference standard strain isolated from chicken) and 1G1 (a clinic isolated strain from duck) were selected to infect chickens, establishing fowl cholera-induced laying hen models. Several important proteins involved in the process of lung injury were identified and quantified using immunohistochemistry and WB. The results showed that chicken lungs infected with bacteria for 24 h showed congestion and edema. The inflammatory factors HMGB1 and IL-6, intercellular matrix MMP, the cell apoptosis-associated caspase-3 and necrotic apoptosis signal molecules RIPK1 and RIPK3 were widely expressed in the lungs of group Q and were significantly different compared with those of 1G1 group and uninfected group (P < 0.05). The results indicated that RIPK1 and RIPK3 are involved in the injury process of chicken lungs after infection with P. multocida, and the mechanisms of lung injury induced by different strains are different. [ABSTRACT FROM AUTHOR]

This report by Jiawei Zhou, Peiwen Ma, Qiyu Tang, Shuhang Wang, and Ning Li analyzes the impact of climate change on the agricultural sector in China. The authors discuss how climate change affects crop production through changes in temperature, precipitation patterns, and extreme weather events. They also highlight the potential consequences, such as decreased crop yields and increased pest and disease outbreaks. The report concludes with recommendations for policymakers and farmers to mitigate the negative effects of climate change on agriculture. [Extracted from the article]

Hemophilia A (HA) is a common X-linked recessive hereditary bleeding disorder. Coagulation factor VIII (FVIII) is insufficient in patients with HA due to the mutations in the F8 gene. The restoration of plasma levels of FVIII via both recombinant B-domain-deleted FVIII (BDD-FVIII) and B-domain-deleted F8 (BDDF8) transgenes was proven to be helpful. FVIII-Padua is a 23.4 kb tandem repeat mutation in the F8 associated with a high F8 gene expression and thrombogenesis. Here we screened a core enhancer element in FVIII-Padua for improving the F8 expression. In detail, we identified a 400 bp efficient enhancer element, C400, in FVIII-Padua for the first time. The core enhancer C400 extensively improved the transcription of BDDF8 driven by human elongation factor-1 alpha in HepG2, HeLa, HEK-293T and induced pluripotent stem cells (iPSCs) with different genetic backgrounds, as well as iPSCs-derived endothelial progenitor cells (iEPCs) and iPSCs-derived mesenchymal stem cells (iMSCs). The expression of FVIII protein was increased by C400, especially in iEPCs. Our research provides a novel molecular target to enhance expression of FVIII protein, which has scientific value and application prospects in both viral and nonviral HA gene therapy strategies. [ABSTRACT FROM AUTHOR]

Vascular calcification is associated with aging, type 2 diabetes, and atherosclerosis, and increases the risk of cardiovascular morbidity and mortality. It is an active, highly regulated process that resembles physiological bone formation. It has previously been established that pharmacological doses of metformin alleviate arterial calcification through adenosine monophosphate‐activated protein kinase (AMPK)‐activated autophagy, however the specific pathway remains elusive. In the present study we hypothesized that metformin protects against arterial calcification through the direct autophagic degradation of runt‐related transcription factor 2 (Runx2). Calcification was blunted in vascular smooth muscle cells (VSMCs) by metformin in a dose‐dependent manner (0.5−1.5 mM) compared to control cells (p < 0.01). VSMCs cultured under high‐phosphate (Pi) conditions in the presence of metformin (1 mM) showed a significant increase in LC3 puncta following bafilomycin‐A1 (Baf‐A; 5 nM) treatment compared to control cells (p < 0.001). Furthermore, reduced expression of Runx2 was observed in the nuclei of metformin‐treated calcifying VSMCs (p < 0.0001). Evaluation of the functional role of autophagy through Atg3 knockdown in VSMCs showed aggravated Pi‐induced calcification (p < 0.0001), failure to induce autophagy (punctate LC3) (p < 0.001) and increased nuclear Runx2 expression (p < 0.0001) in VSMCs cultured under high Pi conditions in the presence of metformin (1 mM). Mechanistic studies employing three‐way coimmunoprecipitation with Runx2, p62, and LC3 revealed that p62 binds to both LC3 and Runx2 upon metformin treatment in VSMCs. Furthermore, immunoblotting with LC3 revealed that Runx2 specifically binds with p62 and LC3‐II in metformin‐treated calcified VSMCs. Lastly, we investigated the importance of the autophagy pathway in vascular calcification in a clinical setting. Ex vivo clinical analyses of calcified diabetic lower limb artery tissues highlighted a negative association between Runx2 and LC3 in the vascular calcification process. These studies suggest that exploitation of metformin and its analogues may represent a novel therapeutic strategy for clinical intervention through the induction of AMPK/Autophagy Related 3 (Atg3)‐dependent autophagy and the subsequent p62‐mediated autophagic degradation of Runx2. [ABSTRACT FROM AUTHOR]

Exosomes, a subset of extracellular vesicles, are released by all active cells and play a crucial role in intercellular communications. Exosomes could facilitate the transfer of various biologically active molecules, such as DNA, non-coding RNAs, and proteins, from donor to recipient cells, thereby participating in diverse biological and pathological processes. Besides, exosomes possess unique characteristics, including non-toxicity, low-immunogenicity, and stability within biological systems, rendering them highly advantageous for cancer drug development. Meanwhile, accumulating evidence suggests that exosomes originating from tumor cells and immune cells possess distinct composition profiles that play a direct role in anticancer immunotherapy. Of note, exosomes can transport their contents to specific cells, thereby exerting an impact on the phenotype and immune-regulatory functions of targeted cells. Therapeutic cancer vaccines, an emerging therapeutics of immunotherapy, could enhance antitumor immune responses by delivering a large number of tumor antigens, thereby augmenting the immune response against tumor cells. Therefore, the therapeutic rationale of cancer vaccines and exosome-based immunotherapy are almost similar to some extent, but some challenges have hindered their application in the clinical setting. Here, in this review, we first summarized the biogenesis, structure, compositions, and biological functions of exosomes. Then we described the roles of exosomes in cancer biology, particularly in tumor immunity. We also comprehensively reviewed current exosome-based anticancer vaccine development and we divided them into three types. Finally, we give some insights into clinical translation and clinical trial progress of exosome-based anticancer vaccines for future direction. • Exosomes are crucial mediators in normal biological processes and cancer development. • Exosomes have dual-effects in immune microenvironment of tumors. • Exosomes could be applied as therapeutic cancer vaccines to induce antitumor immune responses. • The translational application and clinical trials of exosome-based anti-cancer vaccines are promising but challenging. [ABSTRACT FROM AUTHOR]

RÉSUMÉ: CONTEXTE: On donne de façon empirique des agents antiviraux à certains patients atteints de la maladie à coronavirus 2019 (COVID-19). Dans le but d'appuyer la rédaction de lignes directrices sur la prise en charge de la COVID-19, nous avons réalisé une revue systématique des bénéfices et des préjudices associés à 7 traitements antiviraux contre cette infection. MÉTHODES: Nous avons effectué des recherches dans MEDLINE, Embase, le Cochrane Central Register of Controlled Trials (CENTRAL), PubMed et 3 bases de données chinoises (CNKI, Wanfang Data et SinoMed) jusqu'au 19 avril 2020, dans medRxiv et ChinaXiv jusqu'au 27 avril 2020, ainsi que dans Chongqing VIP jusqu'au 30 avril 2020. Nous avons sélectionné des études sur la ribavirine, la chloroquine, l'hydroxychloroquine, l'umifénovir (Arbidol), le favipiravir, l'interféron et le lopinavir/ritonavir. Lorsqu'il n'y avait pas de données directes d'études sur la COVID-19, nous avons retenu des données indirectes d'études sur le syndrome respiratoire aigu sévère (SRAS) et le syndrome respiratoire du Moyen-Orient (SRMO) pour l'analyse de l'efficacité, et d'études sur d'autres infections respiratoires virales aiguës pour l'analyse de l'innocuité. RÉSULTATS: Le taux de décès chez les patients atteints d'une forme sans signe clinique de gravité de COVID-19 était extrêmement bas, ce qui ne permet pas de conclure à un effet important sur la mortalité. Nous n'avons obtenu que des données de très faible qualité indiquant que la plupart des traitements avaient peu ou pas de bénéfices sur les paramètres à l'étude, quelle que soit la gravité de la COVID-19. Seule exception : le traitement au lopinavir/ritonavir, pour lequel nous avons obtenu des données de faible qualité faisant état d'une réduction de la durée du séjour en unité de soins intensifs (différence des risques [DR] 5 jours de moins, intervalle de confiance [IC] de 95 % 0 à 9 jours) et de la durée d'hospitalisation (DR 1 jour de moins, IC de 95 % 0 à 2 jours). En ce qui concerne l'innocuité, les données étaient de faible ou de très faible qualité, sauf pour le traitement au lopinavir/ritonavir, où des données de qualité moyenne laissaient supposer une augmentation probable de la diarrhée, des nausées et des vomissements. INTERPRÉTATION: À l'heure actuelle, rien ne prouve de façon convaincante que les traitements antiviraux apportent des bénéfices importants dans la lutte contre la COVID-19, bien que les données propres à chaque traitement n'excluent pas cette possibilité. D'autres essais randomisés et contrôlés menés auprès de patients atteints de la COVID-19 sont nécessaires avant de pouvoir recourir à ces traitements en toute confiance. [ABSTRACT FROM AUTHOR]

Background: Antiviral medications are being given empirically to some patients with coronavirus disease 2019 (COVID-19). To support the development of a COVID-19 management guideline, we conducted a systematic review that addressed the benefits and harms of 7 antiviral treatments for COVID-19.Methods: We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), PubMed and 3 Chinese databases (CNKI, WANFANG and SinoMed) through Apr. 19, medRxiv and Chinaxiv through Apr. 27, and Chongqing VIP through Apr. 30, 2020. We included studies of ribavirin, chloroquine, hydroxychloroquine, umifenovir (arbidol), favipravir, interferon and lopinavir/ritonavir. If direct evidence from COVID-19 studies was not available, we included indirect evidence from studies of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) for efficacy outcomes and other acute respiratory viral infections for safety outcomes.Results: In patients with nonsevere COVID-19 illness, the death rate was extremely low, precluding an important effect on mortality. We found only very low-quality evidence with little or no suggestion of benefit for most treatments and outcomes in both nonsevere and severe COVID-19. An exception was treatment with lopinavir/ritonavir, for which we found low-quality evidence for a decrease in length of stay in the intensive care unit (risk difference 5 d shorter, 95% confidence interval [CI] 0 to 9 d) and hospital stay (risk difference 1 d shorter, 95% CI 0 to 2 d). For safety outcomes, evidence was of low or very low quality, with the exception of treatment with lopinavir/ritonavir for which moderate-quality evidence suggested likely increases in diarrhea, nausea and vomiting.Interpretation: To date, persuasive evidence of important benefit in COVID-19 does not exist for any antiviral treatments, although for each treatment evidence has not excluded important benefit. Additional randomized controlled trials involving patients with COVID-19 will be needed before such treatments can be administered with confidence. [ABSTRACT FROM AUTHOR]

• NK cells are safe in allogeneic applications and therefore are ideal off-the-shelf drugs. • NK cell-based therapeutics have shown satisfying safety profiles and promising efficiency in cancer treatment. • NK cells possess a reservoir of innate immune receptors targeting various types of cancer cells. • With proper engineering, NK cells can function as the universal anti-cancer drugs that are not restricted to HLA and cancer types. Natural killer (NK) cell therapy is emerging as a cancer treatment. NK cells are innate cytotoxic lymphocytes that act as first-line responders to kill target cells without prior encounters. NK cells recognize cancer cells, virus-infected cells, and other types of stressed cell through a reservoir of germline-encoded receptors. NK cells are safe for allogeneic applications. Therefore, they are the ideal off-the-shelf cell, which overcome the low efficiency issue caused by the patient-by-patient nature of autologous cell therapy. Unlike T cells, NK cells cannot form a strong immune memory; therefore, they suffer from short in vivo persistence. However, different from T cells, NK cells have a reservoir of innate immune receptors targeting a variety of malignant cells. In addition, they can utilize antibody guidance in target recognition. With suitable engineering, NK cells can function as universal anticancer drugs that are not restricted to HLA and cancer types, which will benefit the large cohort of patients with rare cancer types and patients with no convenient drug targets for precision and personalized medicine. Here, we summarize and discuss the designs of current anticancer NK cell therapies. [ABSTRACT FROM AUTHOR]

Drug conjugates are conjugates comprising a tumor-homing carrier tethered to a cytotoxic agent via a linker that are designed to deliver an ultra-toxic payload directly to the target cancer cells. This strategy has been successfully used to increase the therapeutic efficacy of cytotoxic agents and reduce their toxic side effects. Drug conjugates are being developed worldwide, with the potential to revolutionize current cancer treatment strategies. Antibody-drug conjugates (ADCs) have developed rapidly, and 14 of them have received market approval since the first approval event by the Food and Drug Administration in 2000. However, there are some limitations in the use of antibodies as carriers. Other classes of drug conjugates are emerging, such as targeted drugs conjugated with peptides (peptide-drug conjugates, PDCs) and polymers (polymer-drug conjugates, PolyDCs) with the remaining constructs similar to those of ADCs. These novel drug conjugates are gaining attention because they overcome the limitations of ADCs. This review summarizes the current state and advancements in knowledge regarding the design, constructs, and clinical efficacy of different drug conjugates. [ABSTRACT FROM AUTHOR]