The 100 most-cited articles in COVID-19: a bibliometric analysis.

Corona virus disease 2019 (COVID-19) pandemic, sparked by the emergence of a novel coronavirus in early 2020, has prompted a surge in published articles. This study aims to systematically analyse the characteristics and trends of impactful research in the field. The 100 most-cited publications associated with COVID-19 were identified by two independent reviewers using the 'Web of Science' database across all available journals up to the year 2023. Data collected include country, citation count, subject, level of evidence (using Oxford Centre for Evidence-Based Medicine System 2011), impact factor, funding, and study design. We identified 394 038 publications, and the 100 most-cited publications were ranked. These were cited by a total of 283 034 articles (median citation = 767), median impact factor of 66.9 and 72 articles with fundings. China (n = 44), USA (n = 19), and UK (n = 13) were the three highest contributors (n = 220 505). Most articles were level 5 evidence (n = 48), followed by level 3 (n = 28), 4 (n = 14), 2 (n = 7), and 1 (n = 3). The main subjects were mechanism of action and structures of SARS-CoV-2 virus (n = 18) and impact of COVID-19 on public health (n = 18). Publications in 2022 and 2023 predominantly focused on the impact of COVID-19. Majority of the highly cited studies were of low-to-moderate quality, with only 10 consisting of randomized controlled trials or systematic reviews with or without meta-analysis. These findings reflect a growing interest in understanding the impact of COVID-19 pandemic on public and mental health. This analysis found the potential for future double-blinded randomized controlled trials to validate existing findings.

Association of Cannabis Use Disorder with Major Adverse Cardiac and Cerebrovascular Events in Older Non-Tobacco Users: A Population-Based Analysis.

BACKGROUND: Tobacco use disorder (TUD) adversely impacts older patients with established cardiovascular disease (CVD) risk. However, CVD risk in chronic habitual cannabis users without the confounding impact of TUD hasn't been explored. We aimed to determine the risk of major adverse cardiac and cerebrovascular events (MACCE) in older non-tobacco smokers with established CVD risk with vs. without cannabis use disorder (CUD). METHODS: We queried the 2019 National Inpatient Sample for hospitalized non-tobacco smokers with established traditional CVD risk factors aged ≥65 years. Relevant ICD-10 codes were used to identify patients with vs. without CUD. Using multivariable logistic regression, we evaluated the odds of MACCE in CUD cohorts compared to non-CUD cohorts. RESULTS: Prevalence of CUD in the sample was 0.3% (28,535/10,708,815, median age 69), predominantly male, black, and non-electively admitted from urban teaching hospitals. Of the older patients with CVD risk with CUD, 13.9% reported MACCE. The CUD cohort reported higher odds of MACCE (OR 1.20, 95% CI 1.11-1.29, p < 0.001) compared to the non-CUD cohort. Comorbidities such as hypertension (OR 1.9) and hyperlipidemia (OR 1.3) predicted a higher risk of MACCE in the CUD cohort. The CUD cohort also had higher unadjusted rates of acute myocardial infarction (7.6% vs. 6%) and stroke (5.2% vs. 4.8%). CONCLUSIONS: Among older non tobacco smokers with known CVD risk, chronic cannabis use had a 20% higher likelihood of MACCE compared to those who did not use cannabis.

Left Atrial Low Voltage Areas Predicts Recurrence of Atrial Fibrillation after Catheter Ablation: A Meta-Analysis.

BACKGROUND: Low voltage areas (LVAs) on left atrial (LA) voltage mapping correlate with atrial fibrosis. However, there is no uniform standard for the definition of LVAs, or mapping techniques and mapping rhythms, so that the predictive value of left atrial LVAs for recurrence of atrial fibrillation (AF) is uncertain. This study aimed to explore the relationship between the presence of pre-ablation left atrial LVAs and the risk of recurrent AF after catheter ablation. METHODS: The databases of PubMed, Embase, Web of science, Cochrane library, Scopus, Wanfang Datebase, China National Knowledge Infrastructure, China Biology Medicine and China Scientific Journal Datebase were searched from inception to 31 July 2023. Relevant studies regarding left atrial LVAs prior to ablation to predict postoperative recurrence of AF were identified and analyzed. The efficacy endpoints were defined as the recurrence of atrial arrhythmia lasting over 30 s. RESULTS: A total of 12 studies with 1070 patients were included. We found the presence of pre-ablation left atrial LVAs correlated with the risk of recurrent AF after ablation (hazard ratio (HR) = 2.87, 95% confidence interval (CI): 2.33-3.52). The presence of pre-ablation left atrial LVAs can predict the risk of recurrent AF after ablation both in the follow-up duration ≤12 months group and follow-up duration >12 months group (follow-up duration ≤12 months: HR = 2.93, 95% CI: 2.20-3.90; follow-up duration >12 months: HR = 2.80, 95% CI: 2.09-3.77). The presence of pre-ablation left atrial LVAs correlated with the risk of recurrent AF after ablation in paroxysmal AF (HR = 2.89, 95% CI: 1.97-4.24). CONCLUSIONS: The presence of pre-ablation left atrial LVAs correlate with the risk of recurrent AF after catheter ablation.

Dual wave of neutrophil recruitment determines the outcome of C. albicans infection.

Candida albicans is a ubiquitous fungus that can cause superficial and systemic infections in humans. Neutrophils play a crucial role in controlling C. albicans infections. When C. albicans enters the bloodstream, it tends to get trapped in capillary vessels. However, the behavior of neutrophils in combating capillary-residing fungi has not been fully characterized. In this study, we used transgenic mice and whole mount imaging to investigate the growth of C. albicans and its interaction with innate immune cells in different organs. We observed that C. albicans rapidly grows hyphae within hours of infection. Following intravenous infection, we observed two waves of neutrophil recruitment, both of which significantly contributed to the elimination of the fungi. The first wave of neutrophils was induced by complement activation and could be prevented by C5aR blockade. Interestingly, we discovered that the fungicidal effect in the lungs was independent of adhesion molecules such as Mac-1, LFA-1, and ICAM-1. However, these molecules played a more significant role in the optimal killing of C. albicans in the kidney. Importantly, the initial difference in killing efficiency resulted in significantly reduced survival in knockout mice lacking these adhesion molecules. We identified a second wave of neutrophil recruitment associated with hyphal growth and tissue damage, which was independent of the aforementioned adhesion molecules. Overall, this study elucidates the dual wave of neutrophil recruitment during C. albicans infection and highlights the importance of early fungal clearance for favorable disease outcomes.

Notch signalling regulates steroidogenesis in mouse ovarian granulosa cells.

The Notch signalling pathway in the mammalian ovary regulates granulosa cell proliferation. However, the effects of Notch signalling on steroidogenesis are unclear. In this study we cultured mouse ovarian granulosa cells from preantral follicles invitro and observed the effect of Notch signalling on steroidogenesis through overexpression, knockdown and inhibition of Notch signalling. Activation of Notch signalling decreased progesterone and oestrogen secretion. In contrast, inhibition of Notch signalling increased the production of progesterone and oestrogen. Expression of the genes for steroidogenic-related enzymes, including 3ß-hydroxysteroid dehydrogenase, p450 cholesterol side-chain cleavage enzyme and aromatase, was repressed after stimulation of Notch signalling. The expression of upstream transcription factors, including steroidogenic factor 1 (SF1), Wilms' tumour 1 (Wt1), GATA-binding protein 4 (Gata4) and Gata6, was also inhibited after stimulation of Notch signalling. Production of interleukin (IL)-6 was positively correlated with Notch signalling and negatively correlated with the expression of these transcription factors and enzymes. In conclusion, Notch signalling regulated progesterone and oestrogen secretion by affecting the expression of upstream transcription factors SF1, Wt1, Gata4 and Gata6, as well as downstream steroidogenic-related enzymes. IL-6, which may be regulated directly by Notch signalling, may contribute to this process. Our findings add to the understanding of the diverse functions of Notch signalling in the mammalian ovary.

The role of adrenergic activation on murine luteal cell viability and progesterone production.

Sympathetic innervations exist in mammalian CL. The action of catecholaminergic system on luteal cells has been the focus of a variety of studies. Norepinephrine (NE) increased progesterone secretion of cattle luteal cells by activating ß-adrenoceptors. In this study, murine luteal cells were treated with NE and isoprenaline (ISO). We found that NE increased the viability of murine luteal cells and ISO decreased the viability of luteal cells. Both NE and ISO promoted the progesterone production. Nonselective ß-adrenergic antagonist, propranolol reversed the effect of ISO on cell viability but did not reverse the effect of NE on cell viability. Propranolol blocked the influence of NE and ISO on progesterone production. These results reveal that the increase of luteal cell viability induced by NE is not dependent on ß-adrenergic activation. α-Adrenergic activation possibly contributes to it. Both NE and ISO increased progesterone production through activating ß-adrenergic receptor. Further study showed that CyclinD2 is involved in the increase of luteal cell induced by NE. 3ß-Hydroxysteroid dehydrogenase, LHR, steroidogenic acute regulatory protein (StAR), and PGF2α contribute to the progesterone production induced by NE and ISO.

Notch Signaling Pathway Regulates Progesterone Secretion in Murine Luteal Cells.

Notch signaling is an evolutionarily conserved pathway, which involves in various cell life activities. Other studies and our report showed that the Notch signaling plays very important role in follicle development in mammalian ovaries. In luteal cells, Notch ligand, delta-like ligand 4, is involved in normal luteal vasculature. In this study, murine luteal cells were cultured in vitro and treated with Notch signaling inhibitors, L-658,458 and N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycinet-butyl ester (DAPT). We found that L-658,458 and DAPT treatment decrease basal and human chorionic gonadotropin (hCG)-stimulated progesterone secretion. On the contrary, overexpression of intracellular domain of Notch3 increased basal and hCG-stimulated progesterone secretion. Further studies demonstrated that Notch signaling regulated the expression of steroidogenic acute regulatory protein and CYP11A, 2 key enzymes for progesterone synthesis. In conclusion, Notch signaling plays important role in regulating progesterone secretion in murine luteal cells.