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Reconstructing mitochondrial genomes of angiosperms is extremely intricate due to frequent recombinations which give rise to varied sized in Dendrobium mitogenomes and their structural variations, even in most orchid species. In this study, we first sequenced two complete and five draft mitochondrial genomes of Dendrobium using next‐generation and third‐generation sequencing technologies. The mitochondrial genomes were 420 538–689 048 bp long, showing multipartite (multichromosomal) structures that consisted of variably sized circular or linear‐mapping isoforms (chromosomes). The comparison of mitochondrial genomes showed frequent gene losses in Dendrobium species. To explore structure variations of mitochondrial genomes in vivo, we quantified copy numbers of five mitochondrial genes and DNA contents per mitochondrion. The gene copy numbers and the DNA contents showed extreme differences during Dendrobium development, suggesting dynamic structures of mitochondrial genomes. Furthermore, phylogenetic relationships of 97 accessions from 39 Dendrobium species were constructed based on 12 nuclear single‐copy genes and 15 mitochondrial genes. We discovered obvious discordance between the nuclear and mitochondrial trees. Reticulate evolution was inferred from the species network analysis in Dendrobium. Our findings revealed the rapid structural evolution of Dendrobium mitochondrial genomes and the existence of hybridization events in Dendrobium species, which provided new insights into in vivo structural variations of plant mitochondrial genomes and the strong potential of mitochondrial genes in deciphering plant evolution history. [ABSTRACT FROM AUTHOR]

The lack of M–Fe–S (M = Mo or W) clusters incorporating a second period (2p) atom in the core has resulted in limited investigations and poor understanding of the physical and chemical properties of the M–Fe–S clusters closely related to the FeMo cofactor. In this work, systematic studies have been carried out to explore the chemical reactivities at the terminal ligand sites and the redox properties of a series of clusters comprising a [WFe3S3N] cubane core, based on the previously developed cluster [(Tp*)WFe3S3(μ3-NSiMe3)Cl3]1−. Substitutions of the terminal chlorides with ethanethiolate, methanethiolate, thiophenolate, p-thiocresolate and azide occurred smoothly, while the replacement of the chlorides with carbene ligands required the reduction of the precursor into [(Tp*)WFe3S3(μ3-NSiMe3)Cl3]2− first. The reduced cluster core could also be supported by thiophenolates as terminal ligands, but not thiolates or azides. It is remarkable that the thiophenolate ligated reduced cluster can be synthesized from the precursor [(Tp*)WFe3S3(μ3-NSiMe3)Cl3]1−via different synthetic routes, either reduction followed by substitution or substitution followed by reduction, either in situ or stepwise. This work indicates that terminal ligands contribute significantly to determine the chemical and physical properties of the clusters, even though they might affect the cluster core to a limited extent from a structural point of view, which raises the possibility of delicate control in regulating the physical/chemical properties of M–Fe–S clusters with a heteroleptic core incorporating 2p atom(s). [ABSTRACT FROM AUTHOR]

Objective: Previous studies have revealed an intraclass difference in major adverse cardiovascular events (MACE) among sulfonylureas. In vitro and ex vivo studies reported several sulfonylureas to exhibit high-affinity blockage of cardiac mitochondrial ATP-sensitive potassium (mitoKATP) channels and could interfere with ischemic preconditioning, the most important mechanism of self-cardiac protection. However, no studies have examined whether these varying binding affinities of sulfonylureas could account for their intraclass difference in MACE. We compared mitoKATP channel high-affinity versus low-affinity sulfonylureas regarding the MACE risk in real-world settings.Research Design and Methods: Using the Taiwan nationwide health care claims database, patients with type 2 diabetes initiating sulfonylurea monotherapy between 2007 and 2016 were included in the cohort study. A total of 33,727 new mitoKATP channel high-affinity (glyburide and glipizide) and low-affinity (gliclazide and glimepiride) sulfonylurea users, respectively, were identified after 1:1 propensity score matching. Cox proportional hazard models were used to estimate adjusted hazard ratios (aHRs) and 95% CI.Results: MitoKATP channel high-affinity sulfonylureas were associated with a significantly increased risk of three-point MACE (aHR 1.21 [95% CI 1.03-1.44]), ischemic stroke (aHR 1.23 [95% CI 1.02-1.50]), and cardiovascular death (aHR 2.61 [95% CI 1.31-5.20]), but not with that of myocardial infarction (aHR 1.04 [95% CI 0.75-1.46]). The duration-response analyses revealed the highest MACE risk to be within 90 days of therapy (aHR 4.67 [95% CI 3.61-6.06]).Conclusions: Cardiac mitoKATP channel high-affinity sulfonylureas were associated with an increased MACE risk compared with low-affinity sulfonylureas in a nationwide population with diabetes. [ABSTRACT FROM AUTHOR]

Background: Despite multiple available fixed-dose combinations (FDCs) of inhaled long-acting β2-agonists (LABAs) plus long-acting muscarinic antagonists (LAMAs) and LABAs plus inhaled corticosteroids (ICS) for COPD, uncertainty remains regarding their comparative effects.Research Question: Can comparative effectiveness and safety of LABA plus LAMA (LABA/LAMA) and LABA plus ICS (LABA/ICS) FDCs vary by different individual components of the dual combinations in COPD?Study Design and Methods: We conducted a new user, propensity score-inverse probability of treatment weighting cohort study to compare the effectiveness and safety of two frequently used LABA/LAMA FDCs (indacaterol plus glycopyrronium [IND/GLY] and vilanterol plus umeclidinium [VI/UMEC]) vs three commonly prescribed LABA/ICS FDCs (salmeterol plus fluticasone propionate [SAL/FP], formoterol fumarate plus budesonide [FF/BUD], and formoterol fumarate plus beclomethasone dipropionate [FF/BDP]) using the Taiwanese nationwide health care claims from 2014 through 2017. The primary effectiveness outcome was the annual moderate to severe exacerbation rate, and safety outcomes included risks of severe pneumonia and cardiovascular disease requiring hospitalization. Weighted generalized linear mixed models and Cox proportional hazard models were used to assess the effectiveness and safety outcomes, respectively.Results: Patients with COPD initiating IND/GLY and VI/UMEC showed an 11% (incidence rate ratio [IRR], 0.89; 95% CI, 0.80-0.98) and 20% (IRR, 0.80; 95% CI, 0.71-0.90) reduced annual rate of moderate to severe exacerbations, respectively, than those initiating SAL/FP, but showed a similar rate as those initiating FF/BUD or FF/BDP. Both LABA/LAMA FDCs, compared with SAL/FP and VI/UMEC vs FF/BDP, were associated with a 27% (hazard ratio [HR], 0.73; 95% CI, 0.59-0.90) to 42% (HR, 0.58; 95% CI, 0.48-0.70) reduced pneumonia risk. Cardiovascular risk was comparable in five groups. An intraclass difference existed in rates of moderate to severe COPD exacerbation and risks of pneumonia among LABA/ICS FDCs, but not between LABA/LAMA FDCs.Interpretation: Both LABA/LAMAs vs SAL/FP are associated with a lower exacerbation rate and pneumonia risk, but exhibit similar effectiveness and safety outcomes compared with FF/BDP or FF/BUD, suggesting that comparative effects may differ by individual components of the dual therapies in COPD. [ABSTRACT FROM AUTHOR]