Screening of different interactions in oxo-manganese porphyrin dimers containing axial N-donor ligands: a theoretical study

A theoretical analysis for describing the dimeric assemblies of high-valent manganese(v)-oxo meso-tetraphenylporphyrin (TPP) ([(TPP)Mn^VO]₂²⁺) and meso-tetrakis(pentafluorophenyl)porphyrin (TPFPP) ([(TPFPP)Mn^VO]₂²⁺) in the presence of axial N-donor ligands is presented. Our theoretical results revealed two types interactions in dimers: a sandwich-like interaction between phenyl rings of porphyrin molecules, and a non-bonded T-shape interaction between nitrogen donors attached to Mn centers. The curvature in the geometry of porphyrin in the [(TPP)Mn^VO]₂²⁺/N-donor system is significantly smaller than that of [(TPFPP)Mn^VO]₂²⁺/N-donor system. Moreover, the Mn–N_(ax) distances in [(TPFPP)Mn^VO]₂²⁺/N-donor system are shorter than those of [(TPP)Mn^VO]₂²⁺/N-donor system. Also, the donor–acceptor interaction between the imidazoles and the Mn centers are stronger than those of the other ligands in both porphyrins. These results are supported by atoms in molecules (AIM) and natural bond orbital (NBO) analysis.

A DFT analysis for describing the dimeric assemblies of high-valent manganese(v)-oxo meso-tetraphenylporphyrin ([(TPP)Mn^VO]₂²⁺) and meso-tetrakis(pentafluorophenyl)porphyrin ([(TPFPP)Mn^VO]₂²⁺) in the presence of axial N-donor ligands is presented.     

Meta-analysis of epigenome-wide association studies of carotid intima-media thickness

Common carotid intima-media thickness (cIMT) is an index of subclinical atherosclerosis that is associated with ischemic stroke and coronary artery disease (CAD). We undertook a cross-sectional epigenome-wide association study (EWAS) of measures of cIMT in 6400 individuals. Mendelian randomization analysis was applied to investigate the potential causal role of DNA methylation in the link between atherosclerotic cardiovascular risk factors and cIMT or clinical cardiovascular disease. The CpG site cg05575921 was associated with cIMT (beta?=??0.0264, p value?=?3.5?×?10^–8) in the discovery panel and was replicated in replication panel (beta?=??0.07, p value?=?0.005). This CpG is located at chr5:81649347 in the intron 3 of the aryl hydrocarbon receptor repressor gene (AHRR). Our results indicate that DNA methylation at cg05575921 might be in the pathway between smoking, cIMT and stroke. Moreover, in a region-based analysis, 34 differentially methylated regions (DMRs) were identified of which a DMR upstream of ALOX12 showed the strongest association with cIMT (p value?=?1.4?×?10^–13). In conclusion, our study suggests that DNA methylation may play a role in the link between cardiovascular risk factors, cIMT and clinical cardiovascular disease.

     

Carotid Atherosclerosis Is Associated With Poorer Hearing in Older Adults

ObjectivesCardiovascular disease may be linked to hearing loss through narrowing of the nutrient arteries of the cochlea, but large-scale population-based evidence for this association remains scarce. We investigated the association of carotid atherosclerosis as a marker of generalized cardiovascular disease with hearing loss in a population-based cohort.DesignCross-sectional.SettingA population-based cohort study.Participants3724 participants [mean age: 65.5 years, standard deviation (SD): 7.5, 55.4% female].MethodsUltrasound and pure-tone audiograms to assess carotid atherosclerosis and hearing loss.ResultsWe investigated associations of carotid plaque burden and carotid intima-media thickness (IMT) (overall and side-specific carotid atherosclerosis) with hearing loss (in the best hearing ear and side-specific hearing loss) using multivariable linear and ordinal regression models. We found that higher maximum IMT was related to poorer hearing in the best hearing ear [difference in decibel hearing level per 1-mm increase in IMT: 2.09 dB, 95% confidence interval (CI): 0.08, 4.10]. Additionally, third and fourth quartile plaque burden as compared to first quartile was related to poorer hearing in the best hearing ear (difference: 1.06 dB, 95% CI: 0.04, 2.08; and difference: 1.55 dB, 95% CI: 0.49, 2.60, respectively). Larger IMT (difference: 2.97 dB, 95% CI: 0.79, 5.14), third quartile plaque burden compared to first quartile (difference: 1.24 dB, 95% CI: 0.14, 2.35), and fourth plaque quartile compared to first quartile (difference: 2.12 dB, 95% CI: 0.98, 3.26) in the right carotid were associated with poorer hearing in the right ear.Conclusions and ImplicationsCarotid atherosclerosis is associated with poorer hearing in older adults, almost exclusively with poorer hearing in the right ear. Based on our results, it seems that current therapies for the prevention of cardiovascular disease may also prove beneficial for hearing loss in older adults by promoting and maintaining inner ear health.     

Giardiasis in infancy and childhood: a prospective study of 160 cases with comparison of quinacrine (Atabrine) and metronidazole (Flagyl).

The therapeutic effects of quinacrine (Atabrine) and metronidazole (Flagyl) were compared in a 3-year prospective study of 160 infants and children (86 boys and 74 girls ranging in age from 4.5 months to 13 years) with giardiasis. The most common symptom was recurrent abdominal pain. In each study group stool examinations were done 5 days, 1 month, and 6 months after treatment. There were no treatment failures with metronidazole, whereas four of those treated with quinacrine had positive stools 5 days after treatment, indicating possible failure. There were no recurrences at 1 month; after 6 months, however, Giardia infection was found in 13% of both treatment groups. These recurrences were seen mainly in children from families with other infected members. Considering the low failure rate, the minimal side effects, and the relatively more tolerable flavor, metronidazole seems to be preferrable in the treatment of giardiasis. A dosage of 15-25 mg/kg a day for 5 days is recommended.     

NT-proBNP and changes in cognition and global brain structure: The Rotterdam Study

Objective

To investigate the association between N-terminal pro-B-type natriuretic peptide (NT-proBNP) and changes in cognition and global brain structure.

Methods

In the Rotterdam Study, baseline NT-proBNP was assessed at baseline from 1997 to 2008. Between 1997 and 2016, participants without dementia or stroke at baseline (n = 9566) had repeated cognitive tests (every 3–6 years) for global cognitive function, executive cognitive function, fine manual dexterity, and memory. Magnetic resonance imaging of the brain was performed repeatedly at re-examination visits between 2005 and 2015 for 2607 participants to obtain brain volumes, focal brain lesions, and white matter microstructural integrity as measures of brain structure.

Results

Among 9566 participants (mean age 65.1 ± 9.8 years), 5444 (56.9%) were women, and repeated measures of cognition were performed during a median follow-up time of 5.5 (range 1.1–17.9) years, of whom 2607 participants completed at least one brain imaging scan. Higher levels of NT-proBNP were associated with a faster decline of scores in the global cognitive function (p value = 0.003) and the Word-Fluency test (p value = 0.003) but were not related to a steeper deterioration in brain volumes, global fractional anisotropy, and mean diffusivity, as indicators of white matter microstructural integrity, or focal brain lesions.

Conclusions

Higher baseline NT-proBNP levels were associated with a faster decline in cognition; however, no association with global brain structure was found.