Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 25
Filter
1.
J Med Virol ; 96(2): e29472, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38373201

ABSTRACT

Interferons (IFNs) are critical for immune defense against pathogens. While type-I and -III IFNs have been reported to inhibit SARS-CoV-2 replication, the antiviral effect and mechanism of type-II IFN against SARS-CoV-2 remain largely unknown. Here, we evaluate the antiviral activity of type-II IFN (IFNγ) using human lung epithelial cells (Calu3) and ex vivo human lung tissues. In this study, we found that IFNγ suppresses SARS-CoV-2 replication in both Calu3 cells and ex vivo human lung tissues. Moreover, IFNγ treatment does not significantly modulate the expression of SARS-CoV-2 entry-related factors and induces a similar level of pro-inflammatory response in human lung tissues when compared with IFNß treatment. Mechanistically, we show that overexpression of indoleamine 2,3-dioxygenase 1 (IDO1), which is most profoundly induced by IFNγ, substantially restricts the replication of ancestral SARS-CoV-2 and the Alpha and Delta variants. Meanwhile, loss-of-function study reveals that IDO1 knockdown restores SARS-CoV-2 replication restricted by IFNγ in Calu3 cells. We further found that the treatment of l-tryptophan, a substrate of IDO1, partially rescues the IFNγ-mediated inhibitory effect on SARS-CoV-2 replication in both Calu3 cells and ex vivo human lung tissues. Collectively, these results suggest that type-II IFN potently inhibits SARS-CoV-2 replication through IDO1-mediated antiviral response.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/metabolism , Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics , Virus Replication , Lung , Interferons , Epithelial Cells , Antiviral Agents/pharmacology
2.
Respirology ; 28(7): 669-676, 2023 07.
Article in English | MEDLINE | ID: mdl-37106570

ABSTRACT

BACKGROUND AND OBJECTIVE: Although stage I non-small cell lung carcinoma (NSCLC) typically carries a good prognosis following complete resection, early disease recurrence can occur. An accurate survival prediction model would help refine a follow-up strategy and personalize future adjuvant therapy. We developed a post-operative prediction model based on readily available clinical information for patients with stage I adenocarcinoma. METHODS: We retrospectively studied the disease-free survival (DFS) of 408 patients with pathologically confirmed low-risk stage I adenocarcinoma of lung who underwent curative resection from 2013 to 2017. A tree-based method was employed to partition the cohort into subgroups with distinct DFS outcome and stepwise risk ratio. These covariates were included in multivariate analysis to build a scoring system to predict disease recurrence. The model was subsequently validated using a 2011-2012 cohort. RESULTS: Non-smoker status, stage IA disease, epidermal-growth factor receptor mutants and female gender were associated with better DFS. Multivariate analysis identified smoking status, disease stage and gender as factors necessary for the scoring system and yielded 3 distinct risk groups for DFS [99.4 (95% CI 78.3-125.3), 62.9 (95% CI 48.2-82.0), 33.7 (95% CI 24.6-46.1) months, p < 0.005]. External validation yielded an area under the curve by receiver operating characteristic analysis of 0.863 (95% CI 0.755-0.972). CONCLUSION: The model could categorize post-operative patients using readily available clinical information, and may help personalize a follow-up strategy and future adjuvant therapy.


Subject(s)
Adenocarcinoma of Lung , Adenocarcinoma , Lung Neoplasms , Humans , Lung Neoplasms/drug therapy , Retrospective Studies , Neoplasm Staging , Neoplasm Recurrence, Local/epidemiology , Adenocarcinoma of Lung/surgery , Adenocarcinoma of Lung/pathology , Adenocarcinoma/surgery , Adenocarcinoma/pathology , Prognosis
3.
Emerg Infect Dis ; 29(6): 1210-1214, 2023 06.
Article in English | MEDLINE | ID: mdl-37095078

ABSTRACT

Human infection with avian influenza A(H3N8) virus is uncommon but can lead to acute respiratory distress syndrome. In explant cultures of the human bronchus and lung, novel H3N8 virus showed limited replication efficiency in bronchial and lung tissue but had a higher replication than avian H3N8 virus in lung tissue.


Subject(s)
Influenza A Virus, H3N8 Subtype , Influenza, Human , Orthomyxoviridae Infections , Animals , Humans , Lung/diagnostic imaging , Bronchi , Virus Replication
4.
Cell Rep Med ; 3(10): 100774, 2022 10 18.
Article in English | MEDLINE | ID: mdl-36195094

ABSTRACT

"Pan-coronavirus" antivirals targeting conserved viral components can be designed. Here, we show that the rationally engineered H84T-banana lectin (H84T-BanLec), which specifically recognizes high mannose found on viral proteins but seldom on healthy human cells, potently inhibits Middle East respiratory syndrome coronavirus (MERS-CoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (including Omicron), and other human-pathogenic coronaviruses at nanomolar concentrations. H84T-BanLec protects against MERS-CoV and SARS-CoV-2 infection in vivo. Importantly, intranasally and intraperitoneally administered H84T-BanLec are comparably effective. Mechanistic assays show that H84T-BanLec targets virus entry. High-speed atomic force microscopy depicts real-time multimolecular associations of H84T-BanLec dimers with the SARS-CoV-2 spike trimer. Single-molecule force spectroscopy demonstrates binding of H84T-BanLec to multiple SARS-CoV-2 spike mannose sites with high affinity and that H84T-BanLec competes with SARS-CoV-2 spike for binding to cellular ACE2. Modeling experiments identify distinct high-mannose glycans in spike recognized by H84T-BanLec. The multiple H84T-BanLec binding sites on spike likely account for the drug compound's broad-spectrum antiviral activity and the lack of resistant mutants.


Subject(s)
COVID-19 , Middle East Respiratory Syndrome Coronavirus , Humans , SARS-CoV-2 , Lectins/pharmacology , Mannose/pharmacology , Angiotensin-Converting Enzyme 2 , Spike Glycoprotein, Coronavirus/pharmacology , Antiviral Agents/pharmacology
5.
EBioMedicine ; 83: 104232, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35988466

ABSTRACT

BACKGROUND: The Omicron BA.2 sublineage has replaced BA.1 worldwide and has comparable levels of immune evasion to BA.1. These observations suggest that the increased transmissibility of BA.2 cannot be explained by the antibody evasion. METHODS: Here, we characterized the replication competence and respiratory tissue tropism of three Omicron variants (BA.1, BA.1.1, BA.2), and compared these with the wild-type virus and Delta variant, in human nasal, bronchial and lung tissues cultured ex vivo. FINDINGS: BA.2 replicated more efficiently in nasal and bronchial tissues at 33°C than wild-type, Delta and BA.1. Both BA.2 and BA.1 had higher replication competence than wild-type and Delta viruses in bronchial tissues at 37°C. BA.1, BA.1.1 and BA.2 replicated at a lower level in lung parenchymal tissues compared to wild-type and Delta viruses. INTERPRETATION: Higher replication competence of Omicron BA.2 in the human upper airway at 33°C than BA.1 may be one of the reasons to explain the current advantage of BA.2 over BA.1. A lower replication level of the tested Omicron variants in human lung tissues is in line with the clinical manifestations of decreased disease severity of patients infected with the Omicron strains compared with other ancestral strains. FUNDING: This work was supported by US National Institute of Allergy and Infectious Diseases and the Theme-Based Research Scheme under University Grants Committee of Hong Kong Special Administrative Region, China.


Subject(s)
COVID-19 , SARS-CoV-2 , Bronchi , Humans , SARS-CoV-2/genetics , Viral Tropism , Virus Replication
6.
Nature ; 609(7928): 785-792, 2022 09.
Article in English | MEDLINE | ID: mdl-35922005

ABSTRACT

Highly pathogenic coronaviruses, including severe acute respiratory syndrome coronavirus 2 (refs. 1,2) (SARS-CoV-2), Middle East respiratory syndrome coronavirus3 (MERS-CoV) and SARS-CoV-1 (ref. 4), vary in their transmissibility and pathogenicity. However, infection by all three viruses results in substantial apoptosis in cell culture5-7 and in patient tissues8-10, suggesting a potential link between apoptosis and pathogenesis of coronaviruses. Here we show that caspase-6, a cysteine-aspartic protease of the apoptosis cascade, serves as an important host factor for efficient coronavirus replication. We demonstrate that caspase-6 cleaves coronavirus nucleocapsid proteins, generating fragments that serve as interferon antagonists, thus facilitating virus replication. Inhibition of caspase-6 substantially attenuates lung pathology and body weight loss in golden Syrian hamsters infected with SARS-CoV-2 and improves the survival of mice expressing human DPP4 that are infected with mouse-adapted MERS-CoV. Our study reveals how coronaviruses exploit a component of the host apoptosis cascade to facilitate virus replication.


Subject(s)
Aspartic Acid , Caspase 6 , Coronavirus Infections , Coronavirus , Cysteine , Host-Pathogen Interactions , Virus Replication , Animals , Apoptosis , Aspartic Acid/metabolism , Caspase 6/metabolism , Coronavirus/growth & development , Coronavirus/pathogenicity , Coronavirus Infections/enzymology , Coronavirus Infections/virology , Coronavirus Nucleocapsid Proteins/immunology , Coronavirus Nucleocapsid Proteins/metabolism , Cricetinae , Cysteine/metabolism , Dipeptidyl Peptidase 4/genetics , Dipeptidyl Peptidase 4/metabolism , Humans , Interferons/antagonists & inhibitors , Interferons/immunology , Lung/pathology , Mesocricetus , Mice , Middle East Respiratory Syndrome Coronavirus , Severe acute respiratory syndrome-related coronavirus , SARS-CoV-2 , Survival Rate , Weight Loss
7.
Cell Discov ; 8(1): 57, 2022 Jun 17.
Article in English | MEDLINE | ID: mdl-35710786

ABSTRACT

The airways and alveoli of the human respiratory tract are lined by two distinct types of epithelium, which are the primary targets of respiratory viruses. We previously established long-term expanding human lung epithelial organoids from lung tissues and developed a 'proximal' differentiation protocol to generate mucociliary airway organoids. However, a respiratory organoid system with bipotential of the airway and alveolar differentiation remains elusive. Here we defined a 'distal' differentiation approach to generate alveolar organoids from the same source for the derivation of airway organoids. The alveolar organoids consisting of type I and type II alveolar epithelial cells (AT1 and AT2, respectively) functionally simulate the alveolar epithelium. AT2 cells maintained in lung organoids serve as progenitor cells from which alveolar organoids derive. Moreover, alveolar organoids sustain a productive SARS-CoV-2 infection, albeit a lower replicative fitness was observed compared to that in airway organoids. We further optimized 2-dimensional (2D) airway organoids. Upon differentiation under a slightly acidic pH, the 2D airway organoids exhibit enhanced viral replication, representing an optimal in vitro correlate of respiratory epithelium for modeling the high infectivity of SARS-CoV-2. Notably, the higher infectivity and replicative fitness of the Omicron variant than an ancestral strain were accurately recapitulated in these optimized airway organoids. In conclusion, we have established a bipotential organoid culture system able to reproducibly expand the entire human respiratory epithelium in vitro for modeling respiratory diseases, including COVID-19.

8.
J Am Heart Assoc ; 11(10): e024060, 2022 05 17.
Article in English | MEDLINE | ID: mdl-35574957

ABSTRACT

Background Strategies to improve long-term prediction of heart failure and death in valvular surgery are urgently needed because of an increasing number of procedures globally. This study sought to report the prevalence, changes, and prognostic implications of concomitant hepatorenal dysfunction and malnutrition in valvular surgery. Methods and Results In 909 patients undergoing valvular surgery, 3 groups were defined based on hepatorenal function (the modified model for end-stage liver disease excluding international normalized ratio score) and nutritional status (Controlling Nutritional Status score): normal hepatorenal function and nutrition (normal), hepatorenal dysfunction or malnutrition alone (mild), and concomitant hepatorenal dysfunction and malnutrition (severe). Overall, 32%, 46%, and 19% of patients were classified into normal, mild, and severe groups, respectively. Over a 4.1-year median follow-up, mild and severe groups incurred a higher risk of mortality (hazard ratio [HR], 3.17 [95% CI, 1.40-7.17] and HR, 9.30 [95% CI, 4.09-21.16], respectively), cardiovascular death (subdistribution HR, 3.29 [95% CI, 1.14-9.52] and subdistribution HR, 9.29 [95% CI, 3.09-27.99]), heart failure hospitalization (subdistribution HR, 2.11 [95% CI, 1.25-3.55] and subdistribution HR, 3.55 [95% CI, 2.04-6.16]), and adverse outcomes (HR, 2.11 [95% CI, 1.25-3.55] and HR, 3.55 [95% CI, 2.04-6.16]). Modified model for end-stage liver disease excluding international normalized ratio and controlling nutritional status scores improved the predictive ability of European System for Cardiac Operative Risk Evaluation (area under the curve: 0.80 versus 0.73, P<0.001) and Society of Thoracic Surgeons score (area under the curve: 0.79 versus 0.72, P=0.004) for all-cause mortality. One year following surgery (n=707), patients with persistent concomitant hepatorenal dysfunction and malnutrition (severe) experienced worse outcomes than those without. Conclusions Concomitant hepatorenal dysfunction and malnutrition was frequent and strongly linked to heart failure and mortality in valvular surgery.


Subject(s)
Cardiac Surgical Procedures , End Stage Liver Disease , Heart Failure , Malnutrition , Cardiac Surgical Procedures/adverse effects , End Stage Liver Disease/complications , End Stage Liver Disease/diagnosis , End Stage Liver Disease/surgery , Humans , Malnutrition/complications , Malnutrition/diagnosis , Malnutrition/epidemiology , Nutritional Status , Prognosis , Risk Factors , Severity of Illness Index
9.
Front Cardiovasc Med ; 9: 686208, 2022.
Article in English | MEDLINE | ID: mdl-35155624

ABSTRACT

BACKGROUND: The presence of tricuspid regurgitation (TR) is very common in patients with concomitant left-sided valve disease. Recent studies have advocated an additional grading of massive TR that is beyond severe. The present study sought to characterize the spectrum of TR in patients undergoing tricuspid annuloplasty (TA) and to evaluate the prognostic value of TR severity for post-operative outcome following TA. METHODS: A total of 176 patients who underwent TA with combined left-sided valve surgery, secondary to rheumatic valvular heart disease, were prospectively evaluated. The severity of TR was quantified by effective regurgitant orifice area (EROA) using the proximal isovelocity surface area method. Patients were categorized as having non-massive TR (EROA < 0.6 cm2) or massive TR (EROA ≥ 0.6 cm2). Adverse outcome was defined as all-cause mortality or heart failure requiring hospital admission following TA. RESULTS: A total of 55 (31%) patients were considered to have massive TR. Patients with massive TR had a greater right ventricular dimension but a smaller left ventricular dimension compared with those with non-massive TR. After a median follow-up of 39 months, 35 adverse events occurred. Cox-regression analysis showed that both continuous EROA and dichotomized EROA (massive vs. non-massive TR) were independently associated with adverse events even after multivariable adjustment. Further, Harrell C index demonstrated that the addition of massive TR provided better discrimination ability of a prediction model to known prognosticators following TA. CONCLUSIONS: Massive TR is common and up to 31% of study population had massive TR. Massive TR was associated with adverse outcome in patients undergoing TA. Classification of the severity of TR by quantitative measures and identification of massive TR in patients with concomitant left-sided valve disease are essential when considering the optimal timing of corrective surgery.

10.
Nature ; 603(7902): 715-720, 2022 03.
Article in English | MEDLINE | ID: mdl-35104836

ABSTRACT

The emergence of SARS-CoV-2 variants of concern with progressively increased transmissibility between humans is a threat to global public health. The Omicron variant of SARS-CoV-2 also evades immunity from natural infection or vaccines1, but it is unclear whether its exceptional transmissibility is due to immune evasion or intrinsic virological properties. Here we compared the replication competence and cellular tropism of the wild-type virus and the D614G, Alpha (B.1.1.7), Beta (B.1.351), Delta (B.1.617.2) and Omicron (B.1.1.529) variants in ex vivo explant cultures of human bronchi and lungs. We also evaluated the dependence on TMPRSS2 and cathepsins for infection. We show that Omicron replicates faster than all other SARS-CoV-2 variants studied in the bronchi but less efficiently in the lung parenchyma. All variants of concern have similar cellular tropism compared to the wild type. Omicron is more dependent on cathepsins than the other variants of concern tested, suggesting that the Omicron variant enters cells through a different route compared with the other variants. The lower replication competence of Omicron in the human lungs may explain the reduced severity of Omicron that is now being reported in epidemiological studies, although determinants of severity are multifactorial. These findings provide important biological correlates to previous epidemiological observations.


Subject(s)
Bronchi/virology , Lung/virology , SARS-CoV-2/growth & development , Viral Tropism , Virus Replication , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/epidemiology , COVID-19/transmission , COVID-19/virology , Cathepsins/metabolism , Chlorocebus aethiops , Endocytosis , Humans , In Vitro Techniques , SARS-CoV-2/immunology , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism , Tissue Culture Techniques , Vero Cells
11.
Nature ; 593(7859): 418-423, 2021 05.
Article in English | MEDLINE | ID: mdl-33727703

ABSTRACT

The COVID-19 pandemic is the third outbreak this century of a zoonotic disease caused by a coronavirus, following the emergence of severe acute respiratory syndrome (SARS) in 20031 and Middle East respiratory syndrome (MERS) in 20122. Treatment options for coronaviruses are limited. Here we show that clofazimine-an anti-leprosy drug with a favourable safety profile3-possesses inhibitory activity against several coronaviruses, and can antagonize the replication of SARS-CoV-2 and MERS-CoV in a range of in vitro systems. We found that this molecule, which has been approved by the US Food and Drug Administration, inhibits cell fusion mediated by the viral spike glycoprotein, as well as activity of the viral helicase. Prophylactic or therapeutic administration of clofazimine in a hamster model of SARS-CoV-2 pathogenesis led to reduced viral loads in the lung and viral shedding in faeces, and also alleviated the inflammation associated with viral infection. Combinations of clofazimine and remdesivir exhibited antiviral synergy in vitro and in vivo, and restricted viral shedding from the upper respiratory tract. Clofazimine, which is orally bioavailable and comparatively cheap to manufacture, is an attractive clinical candidate for the treatment of outpatients and-when combined with remdesivir-in therapy for hospitalized patients with COVID-19, particularly in contexts in which costs are an important factor or specialized medical facilities are limited. Our data provide evidence that clofazimine may have a role in the control of the current pandemic of COVID-19 and-possibly more importantly-in dealing with coronavirus diseases that may emerge in the future.


Subject(s)
Antiviral Agents/pharmacology , Clofazimine/pharmacology , Coronavirus/classification , Coronavirus/drug effects , SARS-CoV-2/drug effects , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/pharmacology , Adenosine Monophosphate/therapeutic use , Alanine/analogs & derivatives , Alanine/pharmacology , Alanine/therapeutic use , Animals , Anti-Inflammatory Agents/pharmacokinetics , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Antiviral Agents/pharmacokinetics , Antiviral Agents/therapeutic use , Biological Availability , Cell Fusion , Cell Line , Clofazimine/pharmacokinetics , Clofazimine/therapeutic use , Coronavirus/growth & development , Coronavirus/pathogenicity , Cricetinae , DNA Helicases/antagonists & inhibitors , Drug Synergism , Female , Humans , Life Cycle Stages/drug effects , Male , Mesocricetus , Pre-Exposure Prophylaxis , SARS-CoV-2/growth & development , Species Specificity , Spike Glycoprotein, Coronavirus/antagonists & inhibitors , Transcription, Genetic/drug effects , Transcription, Genetic/genetics
12.
Nat Commun ; 12(1): 134, 2021 01 08.
Article in English | MEDLINE | ID: mdl-33420022

ABSTRACT

Understanding the factors that contribute to efficient SARS-CoV-2 infection of human cells may provide insights on SARS-CoV-2 transmissibility and pathogenesis, and reveal targets of intervention. Here, we analyze host and viral determinants essential for efficient SARS-CoV-2 infection in both human lung epithelial cells and ex vivo human lung tissues. We identify heparan sulfate as an important attachment factor for SARS-CoV-2 infection. Next, we show that sialic acids present on ACE2 prevent efficient spike/ACE2-interaction. While SARS-CoV infection is substantially limited by the sialic acid-mediated restriction in both human lung epithelial cells and ex vivo human lung tissues, infection by SARS-CoV-2 is limited to a lesser extent. We further demonstrate that the furin-like cleavage site in SARS-CoV-2 spike is required for efficient virus replication in human lung but not intestinal tissues. These findings provide insights on the efficient SARS-CoV-2 infection of human lungs.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/pathology , COVID-19/transmission , Sialic Acids/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Virus Attachment , Animals , Caco-2 Cells , Cell Line, Tumor , Chlorocebus aethiops , Cricetinae , Furin/metabolism , HEK293 Cells , Heparitin Sulfate/metabolism , Humans , Intestinal Mucosa/metabolism , Intestines/virology , Lung/pathology , Lung/virology , SARS-CoV-2/physiology , Severe Acute Respiratory Syndrome/pathology , Vero Cells , Virus Internalization , Virus Replication/physiology
13.
J Neurosurg Case Lessons ; 2(10): CASE21404, 2021 Sep 06.
Article in English | MEDLINE | ID: mdl-35855190

ABSTRACT

BACKGROUND: Surgical treatment of intrathoracic meningoceles, commonly associated with neurofibromatosis type 1 (NF1), aims to reduce sac size for symptomatic relief. The procedures can be divided into cerebrospinal fluid diversion and definitive repair. The authors describe the management of an intrathoracic meningocele in a 56-year-old female with preexisting NF1. OBSERVATIONS: The patient presented with progressive dyspnea. Magnetic resonance imaging revealed a left hemithoracic meningocele arising from the thecal sac at C7-T2. Two attempts at diversion by cystoperitoneal shunts resulted in recurrence. For definitive repair, T2-3 costotransversectomy was performed, and intradural closure of the meningocele opening was performed utilizing spinal dura and autologous fascia lata graft. Trapezius muscle regional flap was turned for reinforcement. Persistent leak warranted reoperation 7 days later. A transthoracic approach was undertaken using video-assisted thoracoscopic resection of the sac at aortic arch level, with reinforcement by latissimus dorsi flap and synthetic materials. Mechanical pleurodesis was performed. Intradural repair of the meningocele opening was revised. LESSONS: Inherent dural abnormality makes repair difficult for meningoceles associated with NF1. A combined intradural and thoracoscopic approach with regional muscle flap and synthetic material reinforcement is a unique method for definitive treatment. Some essential points of perioperative management are highlighted.

14.
Nature ; 586(7827): 113-119, 2020 10.
Article in English | MEDLINE | ID: mdl-32707573

ABSTRACT

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019 has triggered an ongoing global pandemic of the severe pneumonia-like disease coronavirus disease 2019 (COVID-19)1. The development of a vaccine is likely to take at least 12-18 months, and the typical timeline for approval of a new antiviral therapeutic agent can exceed 10 years. Thus, repurposing of known drugs could substantially accelerate the deployment of new therapies for COVID-19. Here we profiled a library of drugs encompassing approximately 12,000 clinical-stage or Food and Drug Administration (FDA)-approved small molecules to identify candidate therapeutic drugs for COVID-19. We report the identification of 100 molecules that inhibit viral replication of SARS-CoV-2, including 21 drugs that exhibit dose-response relationships. Of these, thirteen were found to harbour effective concentrations commensurate with probable achievable therapeutic doses in patients, including the PIKfyve kinase inhibitor apilimod2-4 and the cysteine protease inhibitors MDL-28170, Z LVG CHN2, VBY-825 and ONO 5334. Notably, MDL-28170, ONO 5334 and apilimod were found to antagonize viral replication in human pneumocyte-like cells derived from induced pluripotent stem cells, and apilimod also demonstrated antiviral efficacy in a primary human lung explant model. Since most of the molecules identified in this study have already advanced into the clinic, their known pharmacological and human safety profiles will enable accelerated preclinical and clinical evaluation of these drugs for the treatment of COVID-19.


Subject(s)
Antiviral Agents/analysis , Antiviral Agents/pharmacology , Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Coronavirus Infections/virology , Drug Evaluation, Preclinical , Drug Repositioning , Pneumonia, Viral/drug therapy , Pneumonia, Viral/virology , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/pharmacology , Alanine/analogs & derivatives , Alanine/pharmacology , Alveolar Epithelial Cells/cytology , Alveolar Epithelial Cells/drug effects , Betacoronavirus/growth & development , COVID-19 , Cell Line , Cysteine Proteinase Inhibitors/analysis , Cysteine Proteinase Inhibitors/pharmacology , Dose-Response Relationship, Drug , Drug Synergism , Gene Expression Regulation/drug effects , Humans , Hydrazones , Induced Pluripotent Stem Cells/cytology , Models, Biological , Morpholines/analysis , Morpholines/pharmacology , Pandemics , Pyrimidines , Reproducibility of Results , SARS-CoV-2 , Small Molecule Libraries/analysis , Small Molecule Libraries/pharmacology , Triazines/analysis , Triazines/pharmacology , Virus Internalization/drug effects , Virus Replication/drug effects , COVID-19 Drug Treatment
15.
Clin Infect Dis ; 71(6): 1400-1409, 2020 09 12.
Article in English | MEDLINE | ID: mdl-32270184

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging coronavirus that has resulted in more than 2 000 000 laboratory-confirmed cases including over 145 000 deaths. Although SARS-CoV-2 and SARS-CoV share a number of common clinical manifestations, SARS-CoV-2 appears to be highly efficient in person-to-person transmission and frequently causes asymptomatic or presymptomatic infections. However, the underlying mechanisms that confer these viral characteristics of high transmissibility and asymptomatic infection remain incompletely understood. METHODS: We comprehensively investigated the replication, cell tropism, and immune activation profile of SARS-CoV-2 infection in human lung tissues with SARS-CoV included as a comparison. RESULTS: SARS-CoV-2 infected and replicated in human lung tissues more efficiently than SARS-CoV. Within the 48-hour interval, SARS-CoV-2 generated 3.20-fold more infectious virus particles than did SARS-CoV from the infected lung tissues (P < .024). SARS-CoV-2 and SARS-CoV were similar in cell tropism, with both targeting types I and II pneumocytes and alveolar macrophages. Importantly, despite the more efficient virus replication, SARS-CoV-2 did not significantly induce types I, II, or III interferons in the infected human lung tissues. In addition, while SARS-CoV infection upregulated the expression of 11 out of 13 (84.62%) representative proinflammatory cytokines/chemokines, SARS-CoV-2 infection only upregulated 5 of these 13 (38.46%) key inflammatory mediators despite replicating more efficiently. CONCLUSIONS: Our study provides the first quantitative data on the comparative replication capacity and immune activation profile of SARS-CoV-2 and SARS-CoV infection in human lung tissues. Our results provide important insights into the pathogenesis, high transmissibility, and asymptomatic infection of SARS-CoV-2.


Subject(s)
Betacoronavirus/physiology , Coronavirus Infections/immunology , Immunity, Innate/immunology , Pneumonia, Viral/immunology , Severe acute respiratory syndrome-related coronavirus/physiology , Virus Replication/immunology , COVID-19 , Chemokines/immunology , Coronavirus Infections/virology , Cytokines/immunology , Humans , Interferons/immunology , Lung/immunology , Lung/virology , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2
17.
J Am Soc Echocardiogr ; 32(12): 1516-1525, 2019 12.
Article in English | MEDLINE | ID: mdl-31563435

ABSTRACT

BACKGROUND: The advent of three-dimensional echocardiography (3DE) enables detailed evaluation of the tricuspid valve (TV) apparatus; nonetheless, the clinical value of preoperative 3DE is unknown in patients undergoing tricuspid annuloplasty (TA). The aim of this study was to evaluate the prognostic value of TV geometric parameters and leaflet coaptation status evaluated by 3DE in patients undergoing TA. METHODS: A total of 122 patients who underwent TA during left-sided heart valve surgery were prospectively evaluated. Detailed 3DE was performed before surgery. Adverse outcome was defined as the occurrence of heart failure requiring hospital admission or all-cause mortality following TA. RESULTS: A total of 33 adverse events (17 heart failures and 16 deaths) occurred during a median follow-up of 36 months. Tethering volume (hazard ratio = 1.32; 95% CI = 1.05-1.66; P = .01) and ratio of total leaflet length to closure length (hazard ratio = 1.07; 95% CI = 1.03-1.12; P < .01) were associated with adverse events after adjustment for age, sex, and tricuspid regurgitation vena contracta width. Receiver-operator characteristic curve analysis revealed that tethering volume (area under curve = 0.73) and ratio of total leaflet length to closure length (area under curve = 0.75) were most associated with adverse events at 1-year follow-up. The presence of either a large tethering volume or a low ratio of total leaflet length to closure length was predictive of an adverse outcome 1 year following TA. CONCLUSIONS: Our study suggests that 3DE-derived TV tethering volume and ratio of total leaflet length to closure length are important preoperative measures associated with adverse events in patients undergoing TA.


Subject(s)
Cardiac Valve Annuloplasty/methods , Echocardiography, Three-Dimensional/methods , Tricuspid Valve Insufficiency/diagnostic imaging , Tricuspid Valve Insufficiency/surgery , Tricuspid Valve/diagnostic imaging , Aged , Cohort Studies , Female , Follow-Up Studies , Humans , Male , Middle Aged , Observer Variation , Prospective Studies , ROC Curve , Risk Assessment , Treatment Outcome , Tricuspid Valve/surgery
18.
J Am Heart Assoc ; 7(14)2018 07 13.
Article in English | MEDLINE | ID: mdl-30006492

ABSTRACT

BACKGROUND: The Model for End-stage Liver Disease excluding international normalized ratio (MELD-XI) score and the modified MELD score with albumin replacing international normalized ratio (MELD-Albumin) score, which reflect both liver and renal function, have been reported as predictors of adverse events in liver and heart disease. Nonetheless, their prognostic value in patients undergoing tricuspid annuloplasty has not been addressed. METHODS AND RESULTS: A total of 394 patients who underwent tricuspid annuloplasty were evaluated. Baseline clinical, laboratory, and echocardiographic parameters were recorded. Adverse outcome was defined as the occurrence of heart failure requiring admission or all-cause mortality. Patients who underwent tricuspid annuloplasty had a high prevalence of preoperative hepatorenal dysfunction that was more common in patients with severe tricuspid regurgitation than those with mild to moderate tricuspid regurgitation. The MELD-XI and MELD-Albumin scores were excellent predictors of 1-year adverse outcome (area under the curve: 0.69 and 0.75, respectively). Kaplan-Meier survival curve demonstrated that a high score on MELD-XI (≥12.0) and MELD-Albumin (≥10.7) was associated with an increased risk of adverse events. During a median follow-up of 40 months, both MELD-XI and MELD-Albumin scores were significantly associated with adverse outcome, even after adjusting for potential confounding factors. Significant improvement of hepatorenal function at 1 year postoperation was noted only in patients who had no adverse events, not in those who experienced an adverse outcome. CONCLUSIONS: Both MELD-XI score and MELD-Albumin score can provide useful information to predict adverse outcome in patients undergoing tricuspid annuloplasty. The present study supports monitoring of modified MELD score to improve preoperative risk stratification of these patients.


Subject(s)
Bilirubin/metabolism , Cardiac Valve Annuloplasty , Creatinine/metabolism , Serum Albumin/metabolism , Tricuspid Valve Insufficiency/surgery , Aged , End Stage Liver Disease , Female , Humans , International Normalized Ratio , Kidney Function Tests , Liver Function Tests , Male , Middle Aged , Prognosis , Proportional Hazards Models , Severity of Illness Index
19.
Int Heart J ; 59(4): 759-765, 2018 Jul 31.
Article in English | MEDLINE | ID: mdl-29925718

ABSTRACT

Concomitant chronic kidney disease (CKD) is common in patients with significant valvular heart disease (VHD). This study sought to evaluate the clinical benefit of valvular surgery in patients with concomitant CKD.We evaluated 349 patients with significant VHD who were referred for surgery. Patients were divided into those with CKD stage ≥ 3 (CKD patients; n = 88) and those with CKD stage 1 or 2 (no CKD patients; n = 261). 63 patients did not receive surgery, of which 20 patients had CKD and 43 had no CKD. Mortality and change in eGFR were assessed after a median follow-up of 21 months.In the whole study population, 25% of the patients had CKD and these patients had higher mortality than those with no CKD. The annual mortality rates of patients with CKD who did and did not undergo surgery were 7.9% and 28.0%, respectively. In patients with no CKD, the annual mortality rates of those who did and did not undergo surgery were 1.8% and 2.3%, respectively. Importantly, surgery was associated with significant survival benefit in patients with CKD (log-rank test, P < 0.01), but was neutral in patients with no CKD. Multivariable analysis confirmed the survival benefit of valvular surgery in all patients, which was most significant in patients with CKD. Furthermore, eGFR was preserved in patients who underwent valvular surgery but declined significantly in those who did not.CKD is common in patients with significant VHD and, if left untreated surgically, these patients exhibit a high mortality.


Subject(s)
Cardiac Surgical Procedures , Heart Valve Diseases , Renal Insufficiency, Chronic , Aged , Cardiac Surgical Procedures/methods , Cardiac Surgical Procedures/statistics & numerical data , Comorbidity , Female , Glomerular Filtration Rate , Heart Valve Diseases/diagnosis , Heart Valve Diseases/epidemiology , Heart Valve Diseases/surgery , Hong Kong/epidemiology , Humans , Kidney Function Tests/methods , Male , Middle Aged , Outcome Assessment, Health Care , Patient Acuity , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/mortality , Survival Analysis
20.
J Cardiol ; 72(3): 247-254, 2018 09.
Article in English | MEDLINE | ID: mdl-29599099

ABSTRACT

BACKGROUND: Tricuspid annuloplasty (TA) is increasingly being performed, but the clinical outcome is unsatisfactory. Acute kidney injury (AKI) is a common complication following cardiac surgery and predicts outcome. Nonetheless the occurrence rate and prognostic value of AKI after TA are unclear. METHODS: This study reviewed 339 consecutive patients (age 65±11 years; male 42%) who underwent TA. The incidence of AKI was defined according to risk/injury/failure/loss/end stage (RIFLE), acute kidney injury network (AKIN), and kidney disease improving global outcomes (KDIGO) criteria, respectively. Major adverse cardiovascular events (MACE) was defined as death, heart failure, stroke, and myocardial infarction (MI). The influence of AKI on MACE was evaluated as a short-term outcome and outcome beyond 30 days. RESULTS: The incidence of AKI, defined according to RIFLE, AKIN, and KDIGO was 57%, 52%, and 53%, respectively. MACE occurred in 94 cases (21 deaths, 63 heart failure requiring hospitalization, 7 stroke, and 3 MI). For short-term outcome, AKI defined by all three scoring systems was independently associated with MACE and death (p<0.01 for both), but not heart failure, stroke, or MI. For outcome beyond 30 days, AKI by all three criteria was associated with MACE and heart failure. Only AKI by AKIN and KDIGO, but not RIFLE, was independently associated with death. CONCLUSION: Our data suggest AKI affects over half of all patients who undergo TA, and has a major and long-lasting impact on survival, MACE, and heart failure. Use of AKIN and KDIGO is more useful than the RIFLE criteria when determining the prognostic value of AKI for mortality beyond 30 days.


Subject(s)
Acute Kidney Injury/mortality , Cardiac Valve Annuloplasty/adverse effects , Cardiovascular Diseases/mortality , Postoperative Complications/mortality , Risk Assessment/methods , Acute Kidney Injury/etiology , Aged , Cardiac Surgical Procedures/adverse effects , Cardiovascular Diseases/etiology , Consensus , Female , Heart Failure/etiology , Heart Failure/mortality , Humans , Incidence , Male , Middle Aged , Myocardial Infarction/etiology , Myocardial Infarction/mortality , Postoperative Complications/etiology , Predictive Value of Tests , Prognosis , Retrospective Studies , Stroke/etiology , Stroke/mortality , Tricuspid Valve/surgery
SELECTION OF CITATIONS
SEARCH DETAIL
...