The burden of coronary revascularization associated with lipoprotein(a) in patients with atherosclerotic cardiovascular disease: data from the UK Biobank

Background/Introduction

Elevated lipoprotein(a) [Lp(a)] is an inherited, independent, and causal risk factor for atherosclerotic cardiovascular disease (ASCVD). In a previous analysis of 30,510 ASCVD patients from UK Biobank, adjusted models showed a 100 nmol/L (≈50 mg/dL) difference in Lp(a) was associated with a 19% (95% CI 14–23%) higher risk of coronary revascularization (Welsh P, 2022).

Purpose

To determine the absolute risk for coronary revascularization in an ASCVD population with elevated versus normal Lp(a) levels.

Methods

This was an observational, retrospective study including 32,537 patients from UK Biobank with an ASCVD diagnosis (CHD, cerebrovascular or peripheral arterial disease). Absolute risk (AR) of coronary revascularization (number of coronary revascularizations per 100-person-years) was reported in patients with normal (<65 nmol/L ≈ 30 mg/dL; n=22,257) and elevated (≥150 nmol/L ≈ 70 mg/dL; n=5,204) Lp(a) levels across two time periods: within the first year of ASCVD diagnosis, and using all available follow-up data (median 4.7 years). Lp(a) was measured in an accredited single laboratory using a method standardized to WHO/IFCC reference material. The AR was also calculated for various subgroups within the ASCVD population.

Results

Within the first year after ASCVD diagnosis, 628 (12.07%) of the population with elevated Lp(a) underwent coronary revascularization compared to 1,787 (8.03%) with normal Lp(a). Those with elevated Lp(a) had a higher AR (14.00 per 100-person-years, 95% CI 13.02–14.99; p<0.001) than those with normal Lp(a) (9.34; 95% CI 8.92–9.76). This also held in a subgroup with myocardial infarction (MI; n=9,588), AR of 18.98 (95% CI 16.95–21.01) in those with elevated Lp(a) (n=1,571) vs. AR of 13.02 (95% CI 12.16–13.89) in those with normal Lp(a) (n=6,441) (p<0.001). AR of coronary revascularization within the first year of ASCVD diagnosis was also greater in participants with family history of CV disease (p<0.001) and premature CV disease (<60 years of age) (p<0.001). When using all available follow-up, AR of coronary revascularization was higher in participants with elevated versus normal Lp(a) in the ASCVD population (3.79 vs 2.55; p<0.001) and across all subgroups.

Conclusion

Elevated Lp(a) in patients with ASCVD was associated with increased risk of coronary revascularization in the first year (and subsequently), including those with a prior MI, premature CV disease, or family history of CV disease. Lp(a) testing in ASCVD patients can therefore aid estimations for the risk of revascularization, and thus the targeting of additional therapies to lower such risks.

Funding Acknowledgement

Type of funding sources: None.

Perceptions of Modulatory Factors in Migraine and Epilepsy: A Multicenter Study

Background: Migraine and epilepsy are both common episodic disorders, typically precipitated or inhibited by some modulatory factors (MFs). Objective: To assess the self-perception of MFs in patients with migraine (PWM) compared to patients with epilepsy (PWE) with a standardized protocol in different countries. Methods: Transcultural multicenter comparative cross-sectional study. All consecutive patients who fulfilled the ICHD-3 criteria for migraine and ILAE's criteria for epilepsy, with at least 1 year of follow-up were interviewed with a semi-structured questionnaire on clinical and epidemiological data and were asked to identify all experienced MFs from a provided list. Results: A total of 608 individuals were surveyed at five university referral centers in Brazil, Guatemala, Lithuania and Turkey. Two hundred and nineteen (91.6%) PWM and 305 (82.7%) PWE identified attack precipitating factors (PFs; p < 0.001). The most frequent three PFs reported by epilepsy patients were: "lack of sleep" (56.6%), "emotional stress" (55.3%), "negative feelings" (53.9%), while among migraine patients "emotional stress" (81.6%), "lack of sleep" (77.8%), "negative feelings" (75.7%) were cited. Inhibitory factors (IFs) for the episodes were reported by 68 (28.5%) PWM and 116 (31.4%) PWE. "Darkness" was the most common one, described by 35.6% of PWM whereas "positive feelings" reported by 10.6% of PWE. Most MFs are concordant across the countries but some transcultural differences were noted. Conclusion: The MFs of migraine and epilepsy attacks and their varying frequencies according to different countries were investigated with the same standardized questionnaire, for the first time. MFs were recognized very often in both migraine and epilepsy cohorts, but in distinct disease-specific prevalence, being more frequent in migraine. Recognition of self-perceived MFs may be helpful for the management of both illnesses.

Entanglement and the nonlinear elastic behavior of forests of coiled carbon nanotubes

Helical or coiled nanostructures have been objects of intense experimental and theoretical studies due to their special electronic and mechanical properties. Recently, it was experimentally reported that the dynamical response of a foamlike forest of coiled carbon nanotubes under mechanical impact exhibits a nonlinear, non-Hertzian behavior, with no trace of plastic deformation. The physical origin of this unusual behavior is not yet fully understood. In this Letter, based on analytical models, we show that the entanglement among neighboring coils in the superior part of the forest surface must be taken into account for a full description of the strongly nonlinear behavior of the impact response of a drop ball onto a forest of coiled carbon nanotubes.

Effect of subinhibitory concentration of piperacillin/tazobactam on Pseudomonas aeruginosa

Subinhibitory concentrations (sub-MICs) of antibiotics, although not able to kill bacteria, can modify their physico-chemical characteristics and the architecture of their outermost surface and may interfere with some bacterial functions. This study investigated the ability of sub-MIC piperacillin/tazobactam (P/T) to interfere with the bacterial virulence parameters of adhesiveness, cell-surface hydrophobicity, motility, biofilm formation and sensitivity to oxidative stress. Antimicrobial activity against five Pseudomonas aeruginosa clinical isolates, representative of clonal lineages of 96 strains of nosocomial origin, and six control strains (ATCC 27853, PAO1, AK1, MT1562, PT623, PAO1algC) was evaluated in vitro using the NCCLS microdilution method. The effects of sub-MIC on bacterial adhesion and biofilm formation were studied using a modified microtitre plate assay. The relative cell-surface hydrophobicity of P. aeruginosa strains was determined by measuring their ability to adhere to n-hexadecane. P. aeruginosa that had been exposed overnight to P/T and incubated with P/T in the plate were also screened for their ability to swim using flagella and to twitch and for their sensitivity to oxidative stress. The results obtained showed that the impact of sub-MIC P/T on bacterial characteristics was different for the various strains of P. aeruginosa. There was a change in bacterial morphology and hydrophobicity that could explain a significant decrease in adhesion values in all clinical isolates and controls tested, a decrease in biofilm formation, a significant increase in sensitivity to oxidative stress, a significant decrease in flagellum-mediated swimming and a decrease in type IV fimbriae-mediated twitching. The results obtained indicate that sub-MIC P/T interferes with the pathogenic potential of P. aeruginosa.

Near equilibrium dynamics of nonhomogeneous Kirchhoff filaments in viscous media

We study the near equilibrium dynamics of nonhomogeneous elastic filaments in viscous media using the Kirchhoff model of rods. Viscosity is incorporated in the model as an external force, which we approximate by the resistance felt by an infinite cylinder immersed in a slowly moving fluid. We use the recently developed method of Goriely and Tabor [Phys. Rev. Lett. 77, 3537 (1996); Physica D 105, 20 (1997); 105, 45 (1997)] to study the dynamics in the vicinity of the simplest equilibrium solution for a closed rod with nonhomogeneous distribution of mass, namely, the planar ring configuration. We show that small variations of the mass density along the rod are sufficient to couple the symmetric modes of the homogeneous rod problem, producing asymmetric deformations that modify substantially the dynamical coiling, even at quite low Reynolds number. The higher-density segments of the rod tend to become more rigid and less coiled. We comment on possible applications to DNA.

Antifungal activity of local anesthetics against Candida species

OBJECTIVE

To evaluate the activity of benzydamine, lidocaine, and bupivacaine, three drugs with local anesthetic activity, against Candida albicans and non-albicans strains and to clarify their mechanism of activity.

METHODS

The minimal inhibitory concentration (MIC) was determined for 20 Candida strains (18 clinical isolates and two American Type Culture Collection strains). The fungistatic activity was studied with the fluorescent probe FUN-1 and observation under epifluorescence microscopy and flow cytometry. The fungicidal activity of the three drugs was assayed by viability counts. Membrane alterations induced in the yeast cells were evaluated by staining with propidium iodide, by quantitation of intracellular K+ leakage and by transmission electron microscopy of intact yeast cells and prepared spheroplasts.

RESULTS

The MIC ranged from 12.5-50.0 microg/mL, 5.0-40.0 mg/mL, and 2.5-10.0 mg/mL for benzydamine, lidocaine, and bupivacaine, respectively. The inhibitory activity of these concentrations could be detected with the fluorescent probe FUN-1 after incubation for 60 minutes. A very fast fungicidal activity was shown by 0.2, 50, and 30 mg/mL of benzydamine, lidocaine, and bupivacaine, respectively.

CONCLUSIONS

At lower concentrations, the tested drugs have a fungistatic activity, due to yeast metabolic impairment, while at higher concentrations they are fungicidal, due to direct damage to the cytoplasmic membrane.

Germ tube formation changes surface hydrophobicity of Candida cells

Hydrophobic interaction is generally considered to play an important role in the adherence of microorganisms to eukaryotic cells and also to certain inert surfaces. Using a microbe adhesion assay to hydrocarbons (n-hexadecane), 68 strains of Candida albicans and 30 non-albicans strains were studied. Influence of source of isolate, age of the culture, and percentage of germ tube formation on adhesion were studied. C. albicans blastoconidia were found to be hydrophilic; conversely, blastoconidia of non-albicans strains were slightly more hydrophobic. Germ tube formation was associated with a significant rise in cell surface hydrophobicity.

Germ tube formation changes surface hydrophobicity of Candida cells

Hydrophobic interaction is generally considered to play an important role in the adherence of microorganisms to eukaryotic cells and also to certain inert surfaces. Using a microbe adhesion assay to hydrocarbons (n-hexadecane), 68 strains of Candida albicans and 30 non-albicans strains were studied. Influence of source of isolate, age of the culture, and percentage of germ tube formation on adhesion were studied. C. albicans blastoconidia were found to be hydrophilic; conversely, blastoconidia of non-albicans strains were slightly more hydrophobic. Germ tube formation was associated with a significant rise in cell surface hydrophobicity.

Prevalence of Candida albicans in vaginal fluid of asymptomatic Portuguese women

Candida albicans is by far the most frequent agent of genital candidosis. We studied the prevalence of C albicans in normal asymptomatic women attending primary health care centers throughout Portugal. The overall prevalence of C albicans in the vaginal fluid of 1,004 women studied was 10.4%. Interestingly, the prevalence rates were lower (6.8%) in women taking combination oral contraceptives and higher (13.0%) in those using intrauterine devices.