International Trends in Adverse Drug Event-Related Mortality from 2001 to 2019: An Analysis of the World Health Organization Mortality Database from 54 Countries

Background and Objective Adverse drug events (ADEs) are becoming a significant public health issue. However, reports on ADE-related mortality are limited to national-level evaluations. Therefore, we aimed to reveal overall trends in ADE-related mortality across the 21st century on an international level. Methods This observational study analysed long-term trends in ADE-related mortality rates from 2001 to 2019 using the World Health Organization Mortality Database. The rates were analysed according to sex, age and region. North America, Latin America and the Caribbean, Western Europe, Eastern Europe and Western Pacific regions were assessed. Fifty-four countries were included with four-character International Statistical Classification of Disease and Related Health Problems, Tenth Revision codes in the database, population data in the World Population Prospects 2019 report, mortality data in more than half of the study period, and high-quality or medium-quality death registration data. A locally weighted regression curve was used to show international trends in age-standardised rates. Results The global ADE-related mortality rate per 100,000 population increased from 2.05 (95% confidence interval 0.92–3.18) in 2001 to 6.86 (95% confidence interval 5.76–7.95) in 2019. Mortality rates were higher among men than among women, especially in those aged 20–50 years. The population aged ≥ 75 years had higher ADE-related mortality rates than the younger population. North America had the highest mortality rate among the five regions. The global ADE-related mortality rate increased by approximately 3.3-fold from 2001 to 2019. Conclusions The burden of ADEs has increased internationally with rising mortality rates. Establishing pharmacovigilance systems can facilitate efforts to reduce ADE-related mortality rates globally

Corneal endothelial expansion promoted by human bone marrow mesenchymal stem cell-derived conditioned medium.

Healthy corneal endothelium is essential for maintaining corneal clarity, as the damage of corneal endothelial cells and loss of cell count causes severe visual impairment. Corneal transplantation is currently the only therapy for severe corneal disorders. The greatly limited proliferative ability of human corneal endothelial cells (HCECs), even in vitro, has challenged researchers to establish efficient techniques for the cultivating HCECs, a pivotal issue for clinical applications. The aim of this study was to evaluate conditioned medium (CM) obtained from human bone marrow-derived mesenchymal stem cells (MSCs) (MSC-CM) for use as a consistent expansion protocol of HCECs. When HCECs were maintained in the presence of MSC-CM, cell morphology assumed a hexagonal shape similar to corneal endothelial cells in vivo, as opposed to the irregular cell shape observed in control cultures in the absence of MSC-CM. They also maintained the functional protein phenotypes; ZO-1 and Na(+)/K(+)-ATPase were localized at the intercellular adherent junctions and pump proteins of corneal endothelium were accordingly expressed. In comparison to the proliferative potential observed in the control cultures, HCECs maintained in MSC-CM were found to have more than twice as many Ki67-positive cells and a greatly increased incorporation of BrdU into DNA. MSC-CM further facilitated the cell migration of HCECs. Lastly, the mechanism of cell proliferation mediated by MSC-CM was investigated, and phosphorylation of Akt and ERK1/2 was observed in HCECs after exposure to MSC-CM. The inhibitor to PI 3-kinase maintained the level of p27(Kip1) for up to 24 hours and greatly blocked the expression of cyclin D1 and D3 during the early G1 phase, leading to the reduction of cell density. These findings indicate that MSC-CM not only stimulates the proliferation of HCECs by regulating the G1 proteins of the cell cycle but also maintains the characteristic differentiated phenotypes necessary for the endothelial functions

MSC-CM-derived factors enhance HCEC proliferation.

<p>(A) HCECs were maintained with basal growth medium supplemented with 1, 3, or 10% of concentrated MSC-CM or full strength MSC-CM. (B) The effect of soluble factors from MSC-CM on the proliferation of HCECs was evaluated by BrdU incorporation assay after 4 days of incubation. * <i>p</i><0.01. The experiments were performed in duplicate. Scale bar: 200 µm.</p

Involvement of PI 3-kinase and ERK1/2 in the proliferation of HCECs in response to MSC-CM stimulation.

<p>(A+B) HCECs were cultured without serum for 24 hours followed by treatment with MSC-CM for 15, 30, 60, or 180 minutes. Phosphorylation of Akt and ERK1/2 was evaluated by Western blot analysis. The experiments were performed in duplicate. (C+D) HCECs were cultured in the presence of the PI 3-kinase inhibitor (LY294002) or MEK inhibitor (U0126). Cell density was evaluated via the use of phase contrast microscopy. The experiments were performed in duplicate. Scale bar: 200 µm. (E) HCECs were cultured without serum for 24 hours, and then treated with MSC-CM in the absence or presence of LY294002. Expression of p27, cyclin D1, and cyclin D3 was evaluated by Western blot analysis, both at the early G1 phase (8 hours) and the late G1 phase (24 hours).</p

Oligonucleotide sequences for RT-PCR.

<p>Oligonucleotide sequences for RT-PCR.</p

MSC-CM promotes cell motility in an <i>in vitro</i> wound model.

<p>(A+B) HCECs were cultured with basal growth medium (control), NIH3T3-CM, or MSC-CM for 40 days, and the monolayer cells were then wounded by scratching. After 20 hours, the remaining wound area was quantified by Image J software. ** <i>p</i><0.05. Scale bar: 200 µm. (C) The speed of cell motility was measured from the image. The experiments were performed in triplicate.</p

MSC-CM and NIH3T3-CM maintain corneal endothelial phenotype <i>in vitro</i> expansion.

<p>(A) Effect of MSC-CM on morphology of primary cultures of HCECs. Representative phase-contrast images of primary culture from different CMs. Cultured HCECs were maintained in basal growth medium, MSC-CM, or NIH3T3-CM for 30 days. Scale bar: 200 µm. (B) HCECs cultured in either MSC-CM or NIH3T3-CM for 14 days expressed ZO-1 and Na⁺/K⁺-ATPase. The pictures are representative of 2 independent experiments. (C) Expression of genes involved in the active transmembrane transporter activity in HCECs cultured with both NIH3T3-CM and MSC-CM was assessed by RT-PCR. The experiments were performed in duplicate.</p