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In response to antigens, B cells undergo affinity maturation and class switching mediated by activation-induced cytidine deaminase (AID) in germinal centers (GCs) of secondary lymphoid organs, but uncontrolled AID activity can precipitate autoimmunity and cancer. The regulation of GC antibody diversification is of fundamental importance but not well understood. We found that autoimmune regulator (AIRE), the molecule essential for T cell tolerance, is expressed in GC B cells in a CD40-dependent manner, interacts with AID and negatively regulates antibody affinity maturation and class switching by inhibiting AID function. AIRE deficiency in B cells caused altered antibody repertoire, increased somatic hypermutations, elevated autoantibodies to T helper 17 effector cytokines and defective control of skin Candida albicans. These results define a GC B cell checkpoint of humoral immunity and illuminate new approaches of generating high-affinity neutralizing antibodies for immunotherapy.
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Carbon nanotubes (CNTs) can be locally grown on custom-designed CMOS microheaters by a thermal chemical vapour deposition (CVD) process to utilize the sensing capabilities of CNTs in emerging micro- and nanotechnology applications. For such a direct CMOS-CNT integration, a key requirement is the development of necessary post-processing steps on CMOS chips for fabricating CMOS-MEMS polysilicon heaters that can locally generate the required CNT synthesis temperatures (~650-900 °C). In our post-CMOS processing, a subtractive fabrication technique is used for micromachining the polysilicon heaters, where the passivation layers in CMOS are used as masks to protect the electronics. For dielectric etching, it is necessary to achieve high selectivity, uniform etching and a good etch rate to fully expose the polysilicon layers without causing damage. We achieved successful post-CMOS processing by developing two-step reactive ion etching (RIE) of the SiO2 dielectric layer and making design improvements to a second-generation CMOS chip. After the dry etching process, CMOS-MEMS microheaters are partially suspended by SiO2 wet etching with minimum damage to the exposed aluminium layers, to obtain high thermal isolation. The fabricated microheaters are then successfully utilized for synthesizing CNTs by a local thermal CVD process. The CMOS post-processing challenges and design aspects to fabricate CMOS-MEMS polysilicon microheaters for such high-temperature applications are detailed in this article. Our developed process for heterogeneous monolithic integration of CMOS-CNT shows promise for wafer-level manufacturing of CNT-based sensors by incorporating additional steps in an already existing foundry CMOS process.
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1. Duck breeding and production are facing great opportunities in China, as the market for small-sized high-quality duck is rapidly expanding. Therefore, breeding the most suitable genetic stock has become an important goal.2. This study assessed body and carcass weight, slaughter rate and meat quality of offspring of three cross combinations; Cherry Valley duck (CVâ) × Small-sized Pekin duck (PKâ), CVâ×Taiwan white duck (TWâ), CVâ×Putian white duck (PTâ) and the corresponding pure lines at 56 d of age. These 420 ducks were raised in seven separate groups (10 pens/group, 3â+3â/pen).3. Body and carcass weights were significantly lower in the three cross combinations than CV ducks (P = 0.042 and P = 0.012). Abdominal fat was lowest in CVâ×PKâ, whereas the breast and the leg muscle weights were significantly higher in CVâ×PKâ compared to CVâ×TWâ and CVâ×PTâ (P = 0.018 and P = 0.023). No difference was observed in the visceral tissues among the three cross combinations or compared to CV ducks.4. The performance indicators suggested that CVâ×PKâ, CVâ×TWâ and CVâ×PTâ cross combinations are best suited for segmented duck meat, featured duck meat and whole-duck processing, respectively.
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Galinhas , Patos , Animais , Patos/genética , Carne/análise , ChinaRESUMO
Two undescribed alkaloids (10 and 11), along with nine known alkaloids (1-9), have been isolated from the stem and root bark of Glycosmis pentaphylla. Among them are carbocristine (11), a carbazole alkaloid first time isolated from a natural source, and acridocristine (10), a pyranoacridone alkaloid first time isolated from the genus "Glycosmis". In vitro cytotoxicity of isolated compounds has been analyzed on breast cancer (MCF-7), lung cancer (CALU-3), and squamous cell carcinoma cell lines (SCC-25). The results demonstrated that compounds are moderately active. In order to study the structural activity relationship of majorly isolated compounds, semisynthetic modifications have been done on majorly isolated compounds such as des-N-methylacronycine (4) and noracronycine (1) to synthesize 11 semisynthetic derivatives (12-22) on functionalizable -NH and -OH groups of the pyranoacridone scaffold at 12th and 6th positions. Semisynthetic derivatives are explored on the same cell lines as isolated compounds, and the results exhibit that semisynthetic compounds showed potent cytotoxic activity compared with naturally isolated compounds. In the case of CALU-3, the dimer at -OH position of noracronycine (1), i.e., compound 22, showed 24-fold better activity with an IC50 of 4.49 µM compared with noracronycine (1) with IC50 97.5 µM. In MCF-7, the dimer at -OH position of noracronycine (1), i.e., compound 22, showed 14-fold better activity with an IC50 of 13.2 µM compared with noracronycine (1) with IC50 187 µM.
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Intoduction: Two scaffold/matrix attachment regions (5'- and 3'-MARsEµ ) flank the intronic core enhancer (cEµ) within the immunoglobulin heavy chain locus (IgH). Besides their conservation in mice and humans, the physiological role of MARsEµ is still unclear and their involvement in somatic hypermutation (SHM) has never been deeply evaluated. Methods: Our study analyzed SHM and its transcriptional control in a mouse model devoid of MARsEµ , further combined to relevant models deficient for base excision repair and mismatch repair. Results: We observed an inverted substitution pattern in of MARsEµ -deficient animals: SHM being decreased upstream from cEµ and increased downstream of it. Strikingly, the SHM defect induced by MARsEµ -deletion was accompanied by an increase of sense transcription of the IgH V region, excluding a direct transcription-coupled effect. Interestingly, by breeding to DNA repair-deficient backgrounds, we showed that the SHM defect, observed upstream from cEµ in this model, was not due to a decrease in AID deamination but rather the consequence of a defect in base excision repair-associated unfaithful repair process. Discussion: Our study pointed out an unexpected "fence" function of MARsEµ regions in limiting the error-prone repair machinery to the variable region of Ig gene loci.
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Reparo de Erro de Pareamento de DNA , Reparo do DNA , Cadeias Pesadas de Imunoglobulinas , Hipermutação Somática de Imunoglobulina , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Íntrons , Fenótipo , Cadeias Pesadas de Imunoglobulinas/genéticaRESUMO
Acute gastrointestinal intestinal GVHD (aGI-GVHD) is a serious complication of allogeneic hematopoietic stem cell transplantation, and the intestinal microbiota is known to impact on its severity. However, an association between treatment response of aGI-GVHD and the intestinal microbiota has not been well-studied. In a cohort of patients with aGI-GVHD (n=37), we found that non-response to standard therapy with corticosteroids was associated with prior treatment with carbapenem antibiotics and loss of Bacteroides ovatus from the microbiome. In a mouse model of carbapenem-aggravated GVHD, introducing Bacteroides ovatus reduced severity of GVHD and improved survival. Bacteroides ovatus reduced degradation of colonic mucus by another intestinal commensal, Bacteroides thetaiotaomicron, via its ability to metabolize dietary polysaccharides into monosaccharides, which then inhibit mucus degradation by Bacteroides thetaiotaomicron and reduce GVHD-related mortality.
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Class-switch recombination (CSR) produces secondary Ig isotypes and requires activation-induced cytidine deaminase (AID)-dependent DNA deamination of intronic switch regions within the IgH (Igh) gene locus. Noncanonical repair of deaminated DNA by mismatch repair (MMR) or base excision repair (BER) creates DNA breaks that permit recombination between distal switch regions. Ataxia telangiectasia mutated (ATM)-dependent phosphorylation of AID at serine 38 (pS38-AID) promotes its interaction with apurinic/apyrimidinic endonuclease 1 (APE1), a BER protein, suggesting that ATM regulates CSR through BER. However, pS38-AID may also function in MMR during CSR, although the mechanism remains unknown. To examine whether ATM modulates BER- and/or MMR-dependent CSR, Atm-/- mice were bred to mice deficient for the MMR gene mutS homolog 2 (Msh2). Surprisingly, the predicted Mendelian frequencies of Atm-/-Msh2-/- adult mice were not obtained. To generate ATM and MSH2-deficient B cells, Atm was conditionally deleted on an Msh2-/- background using a floxed ATM allele (Atmf) and B cell-specific Cre recombinase expression (CD23-cre) to produce a deleted ATM allele (AtmD). As compared with AtmD/D and Msh2-/- mice and B cells, AtmD/DMsh2-/- mice and B cells display a reduced CSR phenotype. Interestingly, Sµ-Sγ1 junctions from AtmD/DMsh2-/- B cells that were induced to switch to IgG1 in vitro showed a significant loss of blunt end joins and an increase in insertions as compared with wild-type, AtmD/D, or Msh2-/- B cells. These data indicate that the absence of both ATM and MSH2 blocks nonhomologous end joining, leading to inefficient CSR. We propose a model whereby ATM and MSH2 function cooperatively to regulate end joining during CSR through pS38-AID.
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Ataxia Telangiectasia , Camundongos , Animais , Proteína 2 Homóloga a MutS/genética , Ataxia Telangiectasia/genética , Quebras de DNA de Cadeia Dupla , Switching de Imunoglobulina/genética , Reparo do DNA , DNA , Citidina Desaminase/genética , Camundongos KnockoutRESUMO
Quantitative proteomics has matured into an established tool and longitudinal proteomics experiments have begun to emerge. However, no effective, simple-to-use differential expression method for longitudinal proteomics data has been released. Typically, such data is noisy, contains missing values, and has only few time points and biological replicates. To address this need, we provide a comprehensive evaluation of several existing differential expression methods for high-throughput longitudinal omics data and introduce a Robust longitudinal Differential Expression (RolDE) approach. The methods are evaluated using over 3000 semi-simulated spike-in proteomics datasets and three large experimental datasets. In the comparisons, RolDE performs overall best; it is most tolerant to missing values, displays good reproducibility and is the top method in ranking the results in a biologically meaningful way. Furthermore, RolDE is suitable for different types of data with typically unknown patterns in longitudinal expression and can be applied by non-experienced users.
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Benchmarking , Proteômica , Proteômica/métodos , Reprodutibilidade dos TestesRESUMO
We propose a mathematical model, namely a reaction-diffusion system, to describe social behaviour of cockroaches. An essential new aspect in our model is that the dispersion behaviour due to overcrowding effect is taken into account as a counterpart to commonly studied aggregation. This consideration leads to an intriguing new phenomenon which has not been observed in the literature. Namely, due to the competition between aggregation towards areas of higher concentration of pheromone and dispersion avoiding overcrowded areas, the cockroaches aggregate more at the transition area of pheromone. Moreover, we also consider the fast reaction limit where the switching rate between active and inactive subpopulations tends to infinity. By utilising improved duality and energy methods, together with the regularisation of heat operator, we prove that the weak solution of the reaction-diffusion system converges to that of a reaction-cross-diffusion system.
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Baratas , Animais , Difusão , Modelos Teóricos , Feromônios , Comportamento SocialRESUMO
The article "Salinomycin enhances radiotherapy sensitivity and reduces expressions of BIRC5 and NEIL2 in nasopharyngeal carcinoma, by Y. Chang, Q. Geng, Q. Bao, P. Hu, published in Eur Rev Med Pharmacol Sci 2020; 24 (11): 6409-6416-DOI: 10.26355/eurrev_202006_21539-PMID: 32572938" has been retracted by the authors. After publication, the article was questioned on PubPeer. Concerns were raised about Figure 3 and the reliability of the published results. The same authors stated that the study was not conducted according to the required standard procedures. The Publisher apologizes for any inconvenience this may cause https://www.europeanreview.org/article/21539.
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Glossopharyngeal neuralgia (GPN) is a painful condition characterized by stabbing pain throughout the glossopharyngeal nerve distribution. Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic, we have learned that COVID-19 may induce neurological symptoms and complications. This case report presents a 54-year-old patient diagnosed with GPN, potentially secondary to COVID-19. The pain resolved spontaneously in three months without the need for medication. We discuss our diagnostic approach for this patient and propose a possible theory about the relation between cranial neuralgias and COVID-19.
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Most cancer cells rely on aerobic glycolysis to support uncontrolled proliferation and evade apoptosis. However, pancreatic cancer cells switch to glutamine metabolism to survive under hypoxic conditions. Activation of the Wnt/ß-catenin pathway induces aerobic glycolysis by activating enzymes required for glucose metabolism and regulating the expression of glutamate transporter and glutamine synthetase. The results demonstrate that riluzole inhibits pancreatic cancer cell growth and has no effect on human pancreatic normal ductal epithelial cells. RNA-seq experiments identified the involvement of Wnt and metabolic pathways by riluzole. Inhibition of Wnt-ß-catenin/TCF-LEF pathway by riluzole suppresses the expression of PDK, MCT1, cMyc, AXIN, and CyclinD1. Riluzole inhibits glucose transporter 2 expression, glucose uptake, lactate dehydrogenase A expression, and NAD + level. Furthermore, riluzole inhibits glutamate release and glutathione levels, and elevates reactive oxygen species. Riluzole disrupts mitochondrial homeostasis by inhibiting Bcl-2 and upregulating Bax expression, resulting in a drop of mitochondrial membrane potential. Finally, riluzole inhibits pancreatic cancer growth in KPC (Pdx1-Cre, LSL-Trp53R172H, and LSL-KrasG12D) mice. In conclusion, riluzole can inhibit pancreatic cancer growth by regulating glucose and glutamine metabolisms and can be used to treat pancreatic cancer.
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Neoplasias Pancreáticas , Riluzol , Via de Sinalização Wnt , beta Catenina , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glutamina/metabolismo , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Riluzol/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo , Neoplasias PancreáticasRESUMO
AIM OF THE STUDY: Nomograms have been proposed to assess prognosis following curative surgery for gastric cancer. The objective of the current study was to evaluate the performance of the Gastric Cancer Collaborative Group nomograms developed in 2014 by Kim et al., using a cohort of patients from a 10-year single institution experience in gastric cancer management. PATIENTS AND METHODS: We retrospectively reviewed patients who underwent curative-intent surgery for histologically confirmed gastric cancer at First Surgical Clinic of Padua University Hospital (Italy) from January 2010 to May 2020. Univariable and multivariable Cox proportional hazard models were employed to assess the effect of the variables of interest on mortality and recurrence. Multivariable analysis was performed by considering the variables included in the Gastric Cancer Collaborative Group nomograms in order to validate them. The performance of the nomograms was evaluated using Harrell's C-index and calibration plots. RESULTS: Overall, 168 patients were included, with a median follow-up of 20.1 months. On multivariable analysis, tumor location, lymph node ratio, and pathological T stage were associated with recurrence; age, tumor location, lymph node ratio, and pT stage were associated with OS (overall survival). The nomograms had good discriminatory capability to classify both OS (C-index: 0.75) and DFS (disease-free survival) (C-index 0.72). The corrected C-Index for DFS based on the AJCC staging system revealed better prediction (C-Index 0.75), while the corrected C-Index for OS had worse discrimination ability compared with the current nomogram (C-Index 0.72). CONCLUSIONS: The Gastric Cancer Collaborative Group nomograms demonstrated good performances in terms of prediction of both OS and DFS on external validation. The two nomograms are easy to apply, and variables included are widely available to most facilities.
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Nomogramas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Estudos Retrospectivos , Prognóstico , Estadiamento de NeoplasiasRESUMO
B cells play a significant role in the adaptive immune response by secreting immunoglobulins that can recognize and neutralize foreign antigens. They develop from hematopoietic stem cells, which also give rise to other types of blood cells, such as monocytes, neutrophils, and T cells, wherein specific transcriptional programs define the commitment and subsequent development of these different cell lineages. A number of transcription factors, such as PU.1, E2A, Pax5, and FOXO1, drive B cell development. Mounting evidence demonstrates that non-coding RNAs, such as microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), modulate the expression of these transcription factors directly by binding to the mRNA coding for the transcription factor or indirectly by modifying cellular pathways that promote expression of the transcription factor. Conversely, these transcription factors upregulate expression of some miRNAs and lncRNAs to determine cell fate decisions. These studies underscore the complex gene regulatory networks that control B cell development during hematopoiesis and identify new regulatory RNAs that require additional investigation. In this review, we highlight miRNAs and lncRNAs that modulate the expression and activity of transcriptional regulators of B lymphopoiesis and how they mediate this regulation.
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Diabetes mellitus (DM), one of the metabolic diseases which is characterized by sustained hyperglycemia, is a life-threatening disease. The global prevalence of DM is on the rise, mainly in low- and middle-income countries. Diabetes is a major cause of blindness, heart attacks, kidney failure, stroke, and lower limb amputation. Type 2 diabetes mellitus (T2DM) is a form of diabetes that is characterized by high blood sugar and insulin resistance. T2DM can be prevented or delayed by a healthy diet, regular physical activity, maintaining normal body weight, and avoiding alcohol and tobacco use. Ethanol and its metabolites can cause differentiation defects in stem cells and promote inflammatory injury and carcinogenesis in several tissues. Recent studies have suggested that diabetes can be treated, and its consequences can be avoided or delayed with proper management. DM has a greater risk for several cancers, such as breast, colorectal, endometrial, pancreatic, gallbladder, renal, and liver cancer. The incidence of cancer is significantly higher in patients with DM than in those without DM. In addition to DM, alcohol abuse is also a risk factor for many cancers. We present a review of the recent studies investigating the association of both DM and alcohol abuse with cancer incidence.
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Alcoolismo/complicações , Diabetes Mellitus Tipo 2/complicações , Neoplasias/complicações , Etanol/metabolismo , Humanos , Modelos Biológicos , Fatores de RiscoRESUMO
Objective: To compare the survival outcome in patients with synchronous colorectal cancer liver metastasis receiving neoadjuvant chemotherapy followed by hepatic surgery versus upfront surgery strategies. Methods: A retrospective cohort study was carried out. Data of patients undergoing surgery at the Department of Hepatopancreatobiliary Surgery Unit I of Peking University Cancer Hospital from January 2008 to December 2018 for initially resectable synchronous colorectal liver metastasis were retrospectively collected. A total of 282 cases were enrolled, including 244 in the neoadjuvant chemotherapy group, 38 in the upfront surgery first group. The overall survival (OS) and progression-free survival (PFS) of the two groups were compared. A propensity score risk adjustment was used to eliminate potential bias between groups, and the covariates including sex, age, location of primary tumor, T stage, clinical risk score (CRS), RAS gene status, adjuvant chemotherapy, and resection margin status were included for adjustment. Results: In the neoadjuvant chemotherapy group, 244 cases received 4 (1-15) cycles of chemotherapy before hepatic resection, among whom 207 cases received oxaliplatin-based regimens, 37 cases received irinotecan-based regimens, and 90 cases received combined targeted agents in the first line treatment. The median follow-up time was 30 (5-134) months, and loss of follow-up was 1%. Before adjustment, Kaplan-Meier survival analysis showed that the 1-year and 3-year OS rates in the neoadjuvant chemotherapy group (95.1% and 66.4%) were better than those in the upfront surgery first group (94.7% and 51.5%, P=0.026); 1-year and 3-year PFS rates in neoadjuvant chemotherapy group (51.0% and 23.4%) were also better than those in surgery first group (39.5% and 11.5%, P=0.039). After propensity score risk adjustment, Cox multivariate analysis indicated that neoadjuvant chemotherapy was an independent protective factor of PFS (HR=0.664, 95% CI: 0.449-0.982, P=0.040), however, neoadjuvant chemotherapy was not an independent protective factor of OS (HR=0.651, 95% CI: 0.393-1.079, P=0.096). Subgroup analysis showed that the 1-year and 3-year OS rates in the patients with response to the first line treatment (194, including complete remission, partial remission and reduction but not partial remission) (96.9% and 67.1%) were better than those in the upfront surgery group (94.7% and 51.5%, P=0.026) after adjustment. However, the 1-year and 3-year OS rates in the patients without response to the first line treatment (50, including tumor progression or enlargement) were 90.0% and 63.3%, respectively, which were not significantly different with 94.7% and 51.5% in the upfront surgery group (P=0.310) after adjustment. Conclusions: For patients with resectable synchronous colorectal cancer liver metastasis, liver resection after neoadjuvant chemotherapy can provide longer PFS than upfront surgery. Although the whole OS benefit is not significant, patients with effective neoadjuvant first-line chemotherapy have better OS than those undergoing upfront surgery.
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Neoplasias Colorretais , Neoplasias Hepáticas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Neoplasias Colorretais/tratamento farmacológico , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Terapia Neoadjuvante , Prognóstico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
B cells produce high-affinity immunoglobulins (Igs), or antibodies, to eliminate foreign pathogens. Mature, naïve B cells expressing an antigen-specific cell surface Ig, or B cell receptor (BCR), are directed toward either an extrafollicular (EF) or germinal center (GC) response upon antigen binding. B cell interactions with CD4+ pre-T follicular helper (pre-Tfh) cells at the T-B border and effector Tfh cells in the B cell follicle and GC control B cell development in response to antigen. Here, we review recent studies demonstrating the role of B cell receptor (BCR) affinity in modulating T-B interactions and the subsequent differentiation of B cells in the EF and GC response. Overall, these studies demonstrate that B cells expressing high affinity BCRs preferentially differentiate into antibody secreting cells (ASCs) while those expressing low affinity BCRs undergo further affinity maturation or differentiate into memory B cells (MBCs).
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Comunicação Celular/imunologia , Diferenciação Celular/imunologia , Centro Germinativo/imunologia , Células B de Memória/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , HumanosRESUMO
There is a pressing need for effective therapeutics for coronavirus disease 2019 (COVID-19), the respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. The process of drug development is a costly and meticulously paced process, where progress is often hindered by the failure of initially promising leads. To aid this challenge, in vitro human microphysiological systems need to be refined and adapted for mechanistic studies and drug screening, thereby saving valuable time and resources during a pandemic crisis. The SARS-CoV-2 virus attacks the lung, an organ where the unique three-dimensional (3D) structure of its functional units is critical for proper respiratory function. The in vitro lung models essentially recapitulate the distinct tissue structure and the dynamic mechanical and biological interactions between different cell types. Current model systems include Transwell, organoid and organ-on-a-chip or microphysiological systems (MPSs). We review models that have direct relevance toward modeling the pathology of COVID-19, including the processes of inflammation, edema, coagulation, as well as lung immune function. We also consider the practical issues that may influence the design and fabrication of MPS. The role of lung MPS is addressed in the context of multi-organ models, and it is discussed how high-throughput screening and artificial intelligence can be integrated with lung MPS to accelerate drug development for COVID-19 and other infectious diseases.
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The article "Circular RNA hsa_circ_0017247 acts as an oncogene in bladder cancer by inducing Wnt/ß-catenin signaling pathway, by C.-T. Han, Q.-Y. Bao, S.-J. Cheng, M. Liu, H.-N. Qian, D. Li, published in Eur Rev Med Pharmacol Sci 2020; 24 (3): 1081-1087-DOI: 10.26355/eurrev_202002_20158-PMID: 32096177" has been withdrawn from the authors since they decided to perform further experiments. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/20158.