ABSTRACT
This paper investigates the tail dependence dynamics and asymmetric risk spillovers between the futures of four important precious metals (gold, silver, platinum, and palladium) and seven leading currencies (EUR, GBP, JPY, CAD, AUD, CHF, and CNY) before and during the COVID-19 crisis using the time-varying-parameter copula and the conditional Value-at-Risk (CoVaR) method. The results show the symmetric dependence between currencies and precious metals before the COVID-19 crisis. In contrast, we show negative and positive tail asymmetric dependences during the pandemic crisis. The COVID-19 crisis significantly amplifies the magnitude of spillover effects among the studied markets where the AUD currency exhibits the largest transmission and reception of downside and upside spillover to/from most precious metals before and during the pandemic crisis. Currency investors and portfolio managers could use the obtained results to better hedge and manage their investment positions when markets are affected by health crises.
ABSTRACT
Coronavirus disease 2019 significantly impacted the liver transplant process worldwide. Consequently, it brought significant challenges and limitations to transplant policies and organ allocation forcing liver transplant centers to adjust their protocols to ensure maximum benefit and avoid harm to their patients. Our center, like many others, was obliged to adapt to the challenges. This paper provided an overview of the effects of coronavirus disease 2019 on liver transplantations and detailed our center's experience and efforts during this unprecedented pandemic to serve as a guide for future public health crises.
ABSTRACT
The coronavirus disease 2019 pandemic has significantly impacted liver tran splantation worldwide, leading to major effects on the transplant process, including the pretransplant, perioperative, and post-transplant periods. It is believed that patients with chronic liver disease, especially those with cirrhosis, have a higher risk of complications from coronavirus disease 2019 infection compared to the general population. However, evaluation of coronavirus disease 2019 effects on liver transplant patients has not uniformly demonstrated worse outcomes. Nonetheless, the pandemic created significant challenges and restrictions on transplant policies and organ allocation.
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This paper examines quantile return spillovers and the connectedness between crude oil futures and key precious metals (PMs) using the approach developed by Ando et al. (2022). Our findings show that using the cross-quantilogram directional spillover method results in significant spillovers from oil to PMs under an extreme downside oil market scenario. Oil impacts both palladium and platinum under an extreme upside oil market status. Under normal oil market conditions, we show insignificant spillovers from oil to PMs. We find an insignificant dependence of PMs on oil during bearish markets, indicating that PMs serve as a safe haven asset. However, we find that oil and palladium are net receivers of spillovers across quantiles, except for palladium at intermediate quantiles, and other PMs are net contributors of spillovers across all quantiles. The spillovers are higher at extreme quantiles and increase during extreme events. Furthermore, we find no connection between platinum and gold under normal market conditions and a weak connection between platinum and both silver and palladium during bearish market scenarios. Precious metals are good diversifying assets for oil portfolios. The hedging strategy using PMs is less expensive during the COVID-19 pandemic than before it, with the exception of platinum. Finally, PMs offer higher hedging effectiveness before the pandemic crisis, whereas palladium provides the highest hedging effectiveness before and during the pandemic crisis.
ABSTRACT
BACKGROUND: Coronavirus (COVID-19) infection exposes patients with heart failure specially who are on mechanical support to a higher risk of morbidity and mortality. AIMS: To investigate the impact of COVID-19 infection on left ventricular assist device (LVAD) thrombosis in heart failure patients. MATERIALS & METHODS: We searched the medical electronic records, Medline, PubMed and Cochrane databases for; (LVAD) AND (thrombosis)) AND (covid-19)) AND (heart failure). We divided cases reported into, LVAD thrombosis with COVID-19 infection and compare them with LVAD thrombosis without COVID-19 infection. Demographic data, LVAD device, presentation, treatment and outcomes were reviewed in all the LVAD thrombosis patients. RESULTS: In addition to our case, 8 other cases of LVAD thrombosis associated with COVID and 9 cases of LVAD thrombosis without covid infection were found. Patients with Covid infection had worse presentation and outcomes (3 deaths VS. 1 death in non-covid group). DISCUSSION: In LVAD patients, pump malfunction due to thrombus development in the inflow cannula, device body, or outflow graft can result in hemodynamic instability, hemolysis and other life-threatening complications. COVID infection significantly increases the risk of mortality in LVAD patient by accelerating the pump thrombosis due to elevated levels of endothelial protein C receptor and thrombomodulin along with procoagulants such as factor VIII, P-selectin, and von Willebrand factor. CONCLUSION: Significant morbidity and mortality are attributed to LVAD thrombosis, which are exasperated by prothrombotic conditions created in COVID-19 infections.
ABSTRACT
Heart transplant surgery is considered the destination therapy for end-stage heart disease. Unfortunately, many patients in the United States of America who are eligible candidates for transplants cannot undergo surgery due to donor shortage. In addition, some donors' hearts are being labeled as unacceptable for transplant surgery because of the rigorous and restricted rules placed on the approval process of using a donor's heart. Over the last few decades, the rising discrepancy between the scarcity of donor hearts and the demand for such organs has led to the discussion of expanding the donor heart selection criteria. A softer view on using marginal hearts for transplants would help those on the waitlist to receive a heart transplant. Marginal hearts that contain the hepatitis c virus (HCV), COVID-19, older age, or repairable heart defects have become viable options to use for a heart transplant. Also, the prioritization based on the new heart allocation system would help efficiently decide which recipients would be the first to get a donor's heart. Recently there has been a consensus to broaden the eligibility of donor's hearts by accepting valvular abnormalities, coronary artery disease, and congenital abnormalities. This review highlights some of those expansions in selection criteria in particular using repairable hearts, which could be fixed in the operating room on the back table before transplantation.
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This paper investigates the relationship between changes in the newspaper-based infectious diseases tracking index (ITI) of Baker et al. (2020) and sectoral stock market returns in the US. Our results spanning the period 1985:01 to 2020:03 reveal the presence of a negative (positive) relationship between returns and ITI at lower (higher) return quantiles (representing different market conditions) in a majority of the sectors. For the health care sector, this relationship is negative at all quantiles. Interestingly, inclusion of the COVID-19 period in the sample data leads to the detection of a stronger relationship for smaller quantiles across all sectors. An asymmetric relationship between returns and the ITI is witnessed across different market conditions for the Consumer Staples, Healthcare, Industrial and Technology sectors. Results from a rolling regression uncover differences in the magnitudes of responses to various infectious diseases over time. Our results carry important implications regarding investment strategies for US sectoral returns in the presence of news relating to infectious diseases.
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BACKGROUND: Considering the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), the clinical implications of gastrointestinal (GI) and hepatic manifestations of coronavirus disease 2019 (COVID-19) in the U.S. population require analysis. METHODS: We retrospectively reviewed all adult patients with COVID-19 admitted to our facility. Patients were divided into two groups based on the presence of GI symptoms and transaminitis at presentation. Univariable analysis was performed to assess the differences between study groups. Kruskal-Wallis and Pearson's chi-square tests were used to compare the median of continuous and categorical variables, respectively. Multivariate logistic regression analysis was performed to identify predictors of mechanical ventilation, cytokine release syndrome (CRS), and mortality after adjusting for baseline variables. RESULTS: A total of 84 patients were analyzed. After adjusting for baseline comorbidities, presence of GI symptoms (aOR, adjusted odds ratio 4.2, 95% CI, 1.17-15.60, p=0.03) and transaminitis on admission (aOR 5.69, 95% CI, 1.47-21.99, p=0.01) were associated with CRS. Transaminitis on admission and elevated total bilirubin during hospitalization were associated with an increased need for mechanical ventilation (aOR 6.17, 95% CI, 1.49-25.44, p=0.02 and aOR 7.29, 95% CI, 1.73-30.75, p=0.007, respectively). An elevated aspartate aminotransferase (AST) on admission (aOR 13.41, 95% CI, 1.08-165.69, p=0.04) and elevated total bilirubin during hospitalization (aOR 82.68, 95% CI, 1.67-4074.8, p=0.02) were independently associated with an increased risk of mortality in COVID-19 patients. CONCLUSION: COVID-19 patients with transaminitis on admission had a higher risk of requiring mechanical ventilation and developing CRS. Patients with elevated AST on admission and elevated total bilirubin had higher mortality. Patients with GI symptoms did not have worse outcomes.