Changes in oral health during aging in a novel non-human primate model

Oral health plays a significant role in the quality of life and overall well-being of the aging population. However, age-related changes in oral health are not well understood due to challenges with current animal models. In this study, we analyzed the oral health and microbiota of a short-lived non-human primate (i.e., marmoset), as a step towards establishing a surrogate for studying the changes that occur in oral health during human aging. We investigated the oral health of marmosets using cadaveric tissues in three different cohorts: young (aged ≤6 years), middle-aged, and older (>10 years) and assessed the gingival bacterial community using analyses of the V3-V4 variable region of 16S rRNA gene. The oldest cohort had a significantly higher number of dental caries, increased dental attrition/erosion, and deeper periodontal pocket depth scores. Oral microbiome analyses showed that older marmosets had a significantly greater abundance of Escherichia-Shigella and Propionibacterium, and a lower abundance of Agrobacterium/Rhizobium at the genus level. Alpha diversity of the microbiome between the three groups showed no significant differences; however, principal coordinate analysis and non-metric multidimensional scaling analysis revealed that samples from middle-aged and older marmosets were more closely clustered than the youngest cohort. In addition, linear discriminant analysis effect size (LEFSe) identified a higher abundance of Esherichia-Shigella as a potential pathogenic biomarker in older animals. Our findings confirm that changes in the oral microbiome are associated with a decline in oral health in aging marmosets. The current study suggests that the marmoset model recapitulates some of the changes in oral health associated with human aging and may provide opportunities for developing new preventive strategies or interventions which target these disease conditions.

Extracellular matrix turnover in salivary gland disorders and regenerative therapies: Obstacles and opportunities

Salivary gland (SG) extracellular matrix (ECM) has a major influence on tissue development, homeostasis, and tissue regeneration after injury. During aging, disease, and physical insult, normal remodeling of the SG microenvironment (i.e. ECM) becomes dysregulated, leading to alterations in matrix composition which disrupt tissue architecture/structure, alter cell activity, and negatively impact gland function. Matrix metalloproteinases (MMPs) are a large and diverse family of metalloendopeptidases which play a major role in matrix degradation and are intimately involved in regulating development and cell function; dysregulation of these enzymes leads to the production of a fibrotic matrix. In the SG this altered fibrotic ECM (or cell microenvironment) negatively impacts normal cell function and the effectiveness of gene and stem cell therapies which serve as a foundation for many SG regenerative therapies. For this reason, prospective regenerative strategies should prioritize the maintenance and/or restoration of a healthy SG ECM. Mesenchymal stem cells (MSCs) have great potential for mitigating damage to the SG microenvironment by ameliorating inflammation, reducing fibrosis, and repairing the damaged milieu of extracellular regulatory cues, including the matrix. This review addresses our current understanding of the impact of aging and disease on the SG microenvironment and suggests critical deficiencies and opportunities in ECM-targeted therapeutic interventions.

Bilateral simultaneous cataract surgery and intraocular lens implantation in an adult female chimpanzee (Pan troglodytes) inducing monovision

BACKGROUND

Cataract is the major cause of visual impairment in humans. Phacoemulsification with intraocular lens (IOL) implantation is the standard technique for cataract treatment with a high success rate. In a few cases, the surgical cataract procedure and lens implantation have been applied in non-human primates.

CASE DESCRIPTION

A +/- 40-year-old female chimpanzee (Pan troglodytes) in captivity was diagnosed with mature cataract optical density (OD) and posterior subcapsular cataract combined with cortical opacities OS after ophthalmic examination. To restore vision and facilitate far- and near sight, phacoemulsification OU with +22.5 diopter (D) IOL implantation OD and + 24 D OS were performed. Despite complicated surgery OD due to posterior capsular rupture, the outcome was successful during 1-year follow-up. The chimpanzee regained adequate vision, normal behavior, and was successfully re-introduced to her group of chimpanzees.

CONCLUSION

This is the first case report of a simultaneous bilateral cataract surgery with IOL implantations in both eyes, targeting emmetropia OS and near vision OD resulting in monovision, in a chimpanzee. Vision was restored without postoperative complications.

Autologous mesenchymal stem cells offer a new paradigm for salivary gland regeneration

Salivary gland (SG) dysfunction, due to radiotherapy, disease, or aging, is a clinical manifestation that has the potential to cause severe oral and/or systemic diseases and compromise quality of life. Currently, the standard-of-care for this condition remains palliative. A variety of approaches have been employed to restore saliva production, but they have largely failed due to damage to both secretory cells and the extracellular matrix (niche). Transplantation of allogeneic cells from healthy donors has been suggested as a potential solution, but no definitive population of SG stem cells, capable of regenerating the gland, has been identified. Alternatively, mesenchymal stem cells (MSCs) are abundant, well characterized, and during SG development/homeostasis engage in signaling crosstalk with the SG epithelium. Further, the trans-differentiation potential of these cells and their ability to regenerate SG tissues have been demonstrated. However, recent findings suggest that the "immuno-privileged" status of allogeneic adult MSCs may not reflect their status post-transplantation. In contrast, autologous MSCs can be recovered from healthy tissues and do not present a challenge to the recipient's immune system. With recent advances in our ability to expand MSCs in vitro on tissue-specific matrices, autologous MSCs may offer a new therapeutic paradigm for restoration of SG function.

Cohort profile: the ESC EURObservational Research Programme Non-ST-segment elevation myocardial infraction (NSTEMI) Registry

AIMS

The European Society of Cardiology (ESC) EURObservational Research Programme (EORP) Non-ST-segment elevation myocardial infarction (NSTEMI) Registry aims to identify international patterns in NSTEMI management in clinical practice and outcomes against the 2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without ST-segment-elevation.

METHODS AND RESULTS

Consecutively hospitalised adult NSTEMI patients (n = 3620) were enrolled between 11 March 2019 and 6 March 2021, and individual patient data prospectively collected at 287 centres in 59 participating countries during a two-week enrolment period per centre. The registry collected data relating to baseline characteristics, major outcomes (in-hospital death, acute heart failure, cardiogenic shock, bleeding, stroke/transient ischaemic attack, and 30-day mortality) and guideline-recommended NSTEMI care interventions: electrocardiogram pre- or in-hospital, pre-hospitalization receipt of aspirin, echocardiography, coronary angiography, referral to cardiac rehabilitation, smoking cessation advice, dietary advice, and prescription on discharge of aspirin, P2Y12 inhibition, angiotensin converting enzyme inhibitor (ACEi)/angiotensin receptor blocker (ARB), beta-blocker, and statin.

CONCLUSION

The EORP NSTEMI Registry is an international, prospective registry of care and outcomes of patients treated for NSTEMI, which will provide unique insights into the contemporary management of hospitalised NSTEMI patients, compliance with ESC 2015 NSTEMI Guidelines, and identify potential barriers to optimal management of this common clinical presentation associated with significant morbidity and mortality.

Matrix-bound Cyr61/CCN1 is required to retain the properties of the bone marrow mesenchymal stem cell niche but is depleted with aging

Previously, we showed that extracellular matrices (ECMs), produced ex vivo by various types of stromal cells, direct bone marrow mesenchymal stem cells (BM-MSCs) in a tissue-specific manner and recapitulate physiologic changes characteristic of the aging microenvironment. In particular, BM-MSCs obtained from elderly donors and cultured on ECM produced by young BM stromal cells showed improved quantity, quality and osteogenic differentiation. In the present study, we searched for matrix components that are required for a functional BM-MSC niche by comparing ECMs produced by BM stromal cells from "young" (≤25 y/o) versus "elderly" (≥60 y/o) donors. With increasing donor age, ECM fibrillar organization and mechanical integrity deteriorated, along with the ability to promote BM-MSC proliferation and responsiveness to growth factors. Proteomic analyses revealed that the matricellular protein, Cyr61/CCN1, was present in young, but undetectable in elderly, BM-ECM. To assess the role of Cyr61 in the BM-MSC niche, we used genetic methods to down-regulate the incorporation of Cyr61 during production of young ECM and up-regulate its incorporation in elderly ECM. The results showed that Cyr61-depleted young ECM lost the ability to promote BM-MSC proliferation and growth factor responsiveness. However, up-regulating the incorporation of Cyr61 during synthesis of elderly ECM restored its ability to support BM-MSC responsiveness to osteogenic factors such as BMP-2 and IGF-1. We next examined aging bone and compared bone mineral density and Cyr61 content of L4-L5 vertebral bodies in "young" (9-11 m/o) and "elderly" (21-33 m/o) mice. Our analyses showed that low bone mineral density was associated with decreased amounts of Cyr61 in osseous tissue of elderly versus young mice. Our results strongly demonstrate a novel role for ECM-bound Cyr61 in the BM-MSC niche, where it is responsible for retention of BM-MSC proliferation and growth factor responsiveness, while depletion of Cyr61 from the BM niche contributes to an aging-related dysregulation of BM-MSCs. Our results also suggest new potential therapeutic targets for treating age-related bone loss by restoring specific ECM components to the stem cell niche.

Organ-specific extracellular matrix directs trans-differentiation of mesenchymal stem cells and formation of salivary gland-like organoids in vivo

BACKGROUND

Current treatments for salivary gland (SG) hypofunction are palliative and do not address the underlying cause or progression of the disease. SG-derived stem cells have the potential to treat SG hypofunction, but their isolation is challenging, especially when the tissue has been damaged by disease or irradiation for head and neck cancer. In the current study, we test the hypothesis that multipotent bone marrow-derived mesenchymal stem cells (BM-MSCs) in a rat model are capable of trans-differentiating to the SG epithelial cell lineage when induced by a native SG-specific extracellular matrix (SG-ECM) and thus may be a viable substitute for repairing damaged SGs.

METHODS

Rat BM-MSCs were treated with homogenates of decellularized rat SG-ECM for one hour in cell suspension and then cultured in tissue culture plates for 7 days in growth media. By day 7, the cultures contained cell aggregates and a cell monolayer. The cell aggregates were hand-selected under a dissecting microscope, transferred to a new tissue culture dish, and cultured for an additional 7 days in epithelial cell differentiation media. Cell aggregates and cells isolated from the monolayer were evaluated for expression of SG progenitor and epithelial cell specific markers, cell morphology and ultrastructure, and ability to form SG-like organoids in vivo.

RESULTS

The results showed that this approach was very effective and guided the trans-differentiation of a subpopulation of CD133-positive BM-MSCs to the SG epithelial cell lineage. These cells expressed amylase, tight junction proteins (Cldn 3 and 10), and markers for SG acinar (Aqp5 and Mist 1) and ductal (Krt 14) cells at both the transcript and protein levels, produced intracellular secretory granules which were morphologically identical to those found in submandibular gland, and formed SG-like organoids when implanted in the renal capsule in vivo.

CONCLUSIONS

The results of this study suggest the feasibility of using autologous BM-MSCs as an abundant source of stem cells for treating SG hypofunction and restoring the production of saliva in these patients.

The Role of Bioelectrical Impedance Analysis in Predicting COVID-19 Outcome

Background

Published data regarding the impact of obesity on COVID-19 outcomes are inconsistent. However, in most studies, body composition was assessed using body mass index (BMI) alone, thus neglecting the presence and distribution of adipose tissue. Therefore, we aimed to investigate the impact of body and visceral fat on COVID-19 outcomes.

Methods

Observational, prospective cohort study included 216 consecutive COVID-19 patients hospitalized at University Clinical Center Kragujevac (Serbia) from October to December 2021. Body composition was assessed using the BMI, body fat percentage (%BF), and visceral fat (VF) via bioelectrical impedance analysis (BIA). In addition to anthropometric measurements, variables in the research were socio-demographic and medical history data, as well as admission inflammatory biomarkers. Primary end-points were fatal outcomes and intensive care unit (ICU) admission.

Results

The overall prevalence of obesity was 39.3% according to BMI and 50.9% according to % BF, while 38.4% of patients had very high VF levels. After adjusting odds ratio values for cofounding variables and obesity-related conditions, all three anthropometric parameters were significant predictors of primary end-points. However, we note that % BF and VF, compared to BMI, were stronger predictors of both mortality (aOR 3.353, aOR 3.05, and aOR 2.387, respectively) and ICU admission [adjusted odds ratio (aOR) 7.141, aOR 3.424, and aOR 3.133, respectively].

Conclusion

Obesity is linked with COVID-19 mortality and ICU admission, with BIA measurements being stronger predictors of outcome compared to BMI use alone.

Sex-related differences in self-reported treatment burden in patients with atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

 Treatment burden (TB) is defined as the patient’s workload of health care and its impact on patient functioning and well-being. High TB can lead to nonadherence, higher risk of adverse outcomes and lower quality of life. We have previously reported a higher TB in patients with atrial fibrillation (AF) vs. those with other chronic conditions. In this analysis, we explored sex-related differences in self-reported TB in AF patients.

Methods

 A single-centre, prospective study included consecutive patients with AF under drug treatment for at least six months before enrolment from April to June 2019. Patients were asked to voluntarily and anonymously answer Treatment Burden Questionnaire (TBQ). All patients signed the written consent for participation.

Results

 Of 331 patients (mean age 65.4 ±10.3 years, mean total AF history 6.41 ±6.62 years), 127 (38.4%) were females. The mean TB was significantly higher in females compared to males (53.7 vs. 42.6 out of 170 points, p < 0.001), also females more frequently reported TB ≥59 points than males (37.8% vs 20.6%, p = 0.001). Item-specific sex-related differences in self-reported TB questionnaire are showed in Figure. Sex-related differences in TB on multivariable regression analyses of the highest TB quartile (≥59 points) are showed in Table.

Conclusion

 Our study was first to explore the sex-specific determinants of TB in AF patients. Females had significantly higher TB compared with males. Approximately 2 in 5 females and 1 in 5 males reported TB ≥59 points, previously shown to be an unacceptable burden of treatment for patients. Using a NOAC rather than VKA in females and a rhythm control strategy in males could decrease TB to acceptable values. Table.Multivariable Logistic Regression analysis of the highest TB quartile (TB ≥59)VariableOR95% CIP valueFemalePPI therapy5.3541.97-14.560.001NOAC0.3190.12-0.830.019Diuretic therapy0.3180.13-0.760.010CHA2DS2-VASc score0.7000.49-0.990.045MaleAblation and/or ECV0.3830.18-0.810.012Supraventricular arrhythmias0.2220.05-0.980.047VKA Vitamin K antagonist; ECV: electrical cardioversion; AF: Atrial fibrillation; PPI: Proton pump inhibitor; PCI: Percutaneous coronary intervention; NOAC: Non-vitamin k antagonist oral anticoagulant.Abstract Figure.

Main determinants of physician-driven amiodarone discontinuation in clinical practice

Funding Acknowledgements

Type of funding sources: None.

Background

Amiodarone is the most prescribed antiarrhythmic drug, but drug-related side effects sometimes result in drug discontinuation. Not infrequently, physicians discontinue amiodarone without a medical reason. We explored the determinants of such permanent drug discontinuation. 

Methods

 A single-centre, longitudinal study included consecutive patients newly prescribed or already taking amiodarone when first seen in our health centre from January 2013 to December 2017. Baseline data were retrieved from the hospital electronic database and patients were scheduled for a follow-up visit in January to March 2019. 

Results

 Of 1212 patients taking amiodarone (mean age 64.2 ±11.2 yrs; female n= 358, 29.5%; median follow-up 22.5 months), the drug was permanently discontinued in 489 (40.3 %), see Figure. On univariate Cox regression analysis, female sex (HR 1.55; 95%CI 1.0-2.3; p = 0.032), non-multimorbidity (2.9; 2.0-4.3; p < 0.001), LV EF (1.0; 1.0-1.1; p < 0.001), NOAC therapy (1.9; 1.2-3.0; p = 0.003) and AF ablation (2.7; 1.5-4.6; P < 0.001) were associated with amiodarone discontinuation. Age (0.9; 0.9-0.9; p < 0.001), CAD (0.3; 0.2-0.5; p < 0.001), HF (0.5; 0.3-0.9; p = 0.020), ventricular arrhythmias (0.1; 0.0-0.3; p < 0.001), stroke (0.2; 0.1-0.9; p = 0.045), CKD (0.5; 0.3-0.9; p = 0.011), ICD (0.1; 0.0-0.6; P = 0.014), LV diastolic (0.9; 0.9-0.9; p = 0.001) and systolic diameter (0.9; 0.9-0.9; p < 0.001), polypharmacy (0.5; 0.3-0.7; P < 0.001), VKA therapy (0.6; 0.4-0.9; p = 0.027), aspirin (0.57; 0.4-0.9; p = 0.011), loop diuretic (0.5; 0.3-0.7; p < 0.001), spironolactone (0.4; 0.2-0.7; p < 0.001) and statin (0.6; 0.4-0.9; p = 0.009) therapy were associated with drug continuation. Multivariable risk factors for amiodarone discontinuation are showed in Table. 

Conclusion

Study showed that within the first two years of treatment, despite persistent indication, amiodarone was discontinued in 1 out of 10 patients in the absence of side effects, mostly in younger patients with less comorbidities, which may not always be justified. There is a need for qualitative research to elucidate the reasons for such physicians’ decisions. Table.Multivariable Cox Proportional HAZARD Regression analysis of permanent Amiodarone discontinuation due to physician decisionVariableHR95% CIP valueAge0.9700.95-0.990.003VT/VF/electrical storm0.1390.04-0.450.001VKA therapy0.5980.38-0.940.026Ablation of AF2.5391.38-4.690.003Number of comorbidities ≤32.0241.26-3.270.004VT ventricular tachycardia; VF: ventricular fibrillation.Abstract Figure.

Oral and Craniofacial Stem Cells: An Untapped Source for Neural Tissue Regeneration

Nerve tissue regeneration continues to represent an intractable obstacle to realizing the promise of tissue engineering. Although neurobiology works to shed light on the mechanisms governing neuronal growth and repair, considerable technical gaps remain that hinder progress. Chief among these is the absence of an appropriate culture environment to faithfully reproduce the neuronal niche ex vivo. We propose that the various multipotent cells found in the oral cavity may represent an important yet underutilized resource for preparing such neurogenic microenvironments. Similar to those of nerve tissue, these cell populations are of ectodermal origin and have clinically demonstrated neurogenic potential. Although there is a lack of consensus on whether putative types of oral and craniofacial stem cells constitute distinct populations, their contribution to neural tissue engineering may be twofold: as a cellular feedstock for neoneurogenesis and for the production of specialized in vitro environments for neurogenic differentiation, phenotype maintenance, and use in therapeutic applications. Impact statement We propose that addressing gaps in understanding the neurogenic role of dental stem cells and their microenvironment may yield efficient and reliable strategies for long-term neuronal cell culture and open new avenues for neural regeneration in both dental, nerve, and other tissues.

Native extracellular matrix, synthesized ex vivo by bone marrow or adipose stromal cells, faithfully directs mesenchymal stem cell differentiation

Mesenchymal stem cells (MSCs) are highly responsive to cues in the microenvironment (niche) that must be recapitulated ex vivo to study their authentic behavior. In this study, we hypothesized that native bone marrow (BM)- and adipose (AD)-derived extracellular matrices (ECM) were unique in their ability to control MSC behavior. To test this, we compared proliferation and differentiation of bone marrow (BM)-derived MSCs when maintained on native decellularized ECM produced by BM versus AD stromal cells (i.e. BM- versus AD-ECM). We found that both ECMs contained similar types of collagens but differed in the relative abundance of each. Type VI collagen was the most abundant (≈60% of the total collagen present), while type I was the next most abundant at ≈30%. These two types of collagen were found in nearly equal proportions in both ECMs. In contrast, type XII collagen was almost exclusively found in AD-ECM, while types IV and V were only found in BM-ECM. Physically and mechanically, BM-ECM was rougher and stiffer, but less adhesive, than AD-ECM. During 14 days in culture, both ECMs supported BM-MSC proliferation better than tissue culture plastic (TCP), although MSC-related surface marker expression remained relatively high on all three culture surfaces. BM-MSCs cultured in osteogenic (OS) differentiation media on BM-ECM displayed a significant increase in calcium deposition in the matrix, indicative of osteogenesis, while BM-MSCs cultured on AD-ECM in the presence of adipogenic (AP) differentiation media showed a significant increase in Oil Red O staining, indicative of adipogenesis. Further, culture on BM-ECM significantly increased BM-MSC-responsiveness to rhBMP-2 (an osteogenic inducer), while culture on AD-ECM enhanced responsiveness to rosiglitazone (an adipogenic inducer). These findings support our hypothesis and indicate that BM- and AD-ECMs retain unique elements, characteristic of their tissue-specific microenvironment (niche), which promote retention of MSC differentiation state (i.e. "stemness") during expansion and direct cell response to lineage-specific inducers. This study provides a new paradigm for precisely controlling MSC fate to a desired cell lineage for tissue-specific cell-based therapies.

P1866Catheter-ablation of paroxysmal atrial fibrillation is associated with improvement of maximal cardiopulmonary exercise capacity

Background and purpose

Catheter-ablation (CA) of paroxysmal atrial fibrillation (AF) is associated with improvement in symptoms and quality of life (QoL), whilst the effects on functional capacity are underreported. We studied the change in cardiopulmonary exercise testing (CPET) indices of functional capacity from baseline to follow-up in patients undergoing their first CA for paroxysmal AF.

Methods

Consecutive patients who underwent their first CA for paroxysmal AF in our center during 2015, with a >12-month post-procedural follow-up were included. All patients completed the CPET and SF-36 (Short Form Health Survey) questionnaire to evaluate maximal functional capacity and QoL, respectively, at baseline (prior to CA) and 1 year post-CA. The follow-up 24h-Holter-monitoring was performed at 1, 3, 6 and 12 months after CA; finding of any atrial tachyarrhythmia lasting >30 sec was considered the arrhythmia recurrence.

Results

Study group consisted of 50 patients (the mean age 57±12 years, males 76%). The mean left ventricular ejection fraction and left atrial diameter were 61±8% and 41±6 mm, respectively. All patients were free of heart failure; the commonest comorbidities were hypertension (65%) and diabetes mellitus (21%). The follow-up CPET 1 year post CA demonstrated an improvement in maximal functional capacity compared to baseline values, with significant increase in maximal load (123±38 vs. 134±33 W, p=0.012), peak oxygen consumption (VO2max, 18±5 vs. 20±4 mL kg–1 min–1, p=0.001) and peak breathing equivalent (EQ-O2, 28±4 vs. 29±4, p=0.020). The AF-free patients (n=40) had a greater 1-year improvement in work time (22±129 vs. −71±123 sec, p=0.008) and maximal load (15±24 vs. −6±26 W, p=0.005) compared with those expiriencing AF recurrence post-CA (n=10). There was a significant correlation between the 1-year change in SF-36 score and the increase in maximal load (ρ=0.26, p=0.018) and between the 1-year change in SF-36 score and the prolongation of work time (ρ=0.27, p=0.017).

Conclusion

Our study suggests that CA of paroxysmal AF favourably affects the maximal functional capacity, especially in patients with stable sinus rhythm following the procedure. The increase in functional capacity is followed by QoL improvement. This should be considered in treatment decision-making.

P1900Amiodarone treatment duration and reasons for permanent drug discontinuation in patients with atrial fibrillation

Background and purpose

Amiodarone is commonly use in patients with atrial fibrillation (AF), but the organ toxicity side effects limit its long-term use. We investigated the rates of and reasons for permanent amiodarone discontinuation among patients with AF in contemporary clinical practice.

Methods

A single-centre, ongoing, registry-based observational longitudinal study included consecutive AF patients prescribed with amiodarone in our hospital from January 2015 to December 2017. All patients underwent a loading protocol of 400–600 mg of amiodarone daily for 1–2 weeks, followed by 200–400mg daily for 4–8 weeks and 200mg daily or 1000mg weekly thereafter.

Results

Of 657 AF patients taking amiodarone (Mean age 62.2±11.0, female n=215 (32.6%), hypertension n=504 (76.7%), diabetes mellitus n=107 (16.3%), coronary arterial disease n=139 (19.8%), History of Myocardial infarction 86 (13.1%), Stroke/TIA 60 (9.1%), chronic kidney disease 157 (23.9%)), the drug was permanently discontinued in total of 248 patients (37.7%). The reasons for amiodarone discontinuation are shown in Figure. On multivariable Cox-regression analysis, physician's decision (HR 5.6; 95% CI 3.9–7.9, p<0.001) and amiodarone side effects (HR 3.9; 95% CI 2.9–5.1, p<0.001) were significantly associated with permanent amiodarone discontinuation.

The overall time to discontinuation was 23.2±24.1 months. Compared with others, time to discontinuation was shorter in patients post AF ablation (17.3±21.3 vs 24.5±24.5, p=0.05), longer in those with AF progression (29.2±31.0 vs 20.9±20.3, p=0.014) and similar in patients with amiodarone side effects (23.7±17.7 vs 23.0±26.8, p=0.813). Pulmonary toxicity and proarrhythmia were not observed among study patients (Figure).

Chart 1

Conclusion

Our study showed that permanent discontinuation of amiodarone in contemporary clinical practice was due to the drug side effects in 12% of amiodarone-treated AF patients, occurring after a mean 2-year treatment course. The most prevalent side effect was thyroid dysfunction, whereas the prevalence of proarrhythmic effect was low. Notably, physician's fear of complications (which may not always be justified), also was an independent driver of permanent amiodarone discontinuation. More data are needed to inform optimal amiodarone use in AF patients in daily practice.

P1886Validation of the MB-LATER score prediction ability for recurrent atrial fibrillation after electrical cardioversion

Introduction

The MB-LATER score (Male, Bundle brunch block, Left atrium ≥47 mm, Type of AF [paroxysmal, persistent or long-standing persistent], and ER-AF=early recurrent AF during first three months) was originally developed for prediction of late AF recurrences post AF catheter ablation (CA-AF). Subsequently, the score has been internationally validated in multiple AF cohorts, showing a good prediction ability for recurrent AF post AF-CA. We assessed prediction ability of the MB-LATER score for recurrent AF after successful electrical cardioversion (ECV) of AF.

Methods

The retrospective study included a Serbian and Icelandic centre, enrolling patients post successful ECV of AF in the period between January 2014 and February 2016. Of 580 patients, 136 (23.4%) were excluded because incomplete data needed for the MB-LATER score calculation. AF episodes lasting ≤7 days before ECV were classified as paroxysmal AF, and the ER-AF component of the MB-LATER score was excluded from the analysis because of different clinical implications in the setting of ECV. The study outcome was defined as the time to first recurrence of AF post successful ECV. Patients post successful ECV were seen at 1 and 6 months post ECV and every 12 months thereafter.

Results

Among 444 patients (median age 68 years [IQR 60.0–74.6], 289 males [65.2%], 200 [45.0%] with non-paroxysmal AF. AF re-occurred in 283 patients (63.7%) after a median of 233.5 [IQR 44–366]) days post successful ECV. Patients with recurrent AF had significantly higher median MB-LATER score than those without (1 [IQR 1–2] vs. 2 [IQR 1–2], p<0.001). On univariate analysis, the MB-LATER score was significantly associated with time to AF recurrence post ECV (Hazard Ratio 1.20; 95% CI 1.07–1.35, p=0.003), showing modest but statistically significant prediction ability for recurrent AF post successful ECV (c-statistic 0.61; 95% CI 0.56–0.66, p<0.001). The Kaplan-Meyer survival free from AF post successful ECV was significantly better for patients with a MB-LATER score of <2 than for those with a score of ≥2 (log-rank p=0.005) (Fig 1.).

Figure 1

Conclusion

In our analysis of an international cohort of AF patients post successful ECV, the MB-LATER score showed a modest but statistically significant prediction ability for recurrent AF post ECV. Reliable prediction of recurrent AF post ECV could inform patient selection and treatment decision-making. Further prospective validation of the MB-LATER score prediction ability for recurrent AF post ECV is underway.

Restoring the quantity and quality of elderly human mesenchymal stem cells for autologous cell-based therapies

BACKGROUND

Degenerative diseases are a major public health concern for the aging population and mesenchymal stem cells (MSCs) have great potential for treating many of these diseases. However, the quantity and quality of MSCs declines with aging, limiting the potential efficacy of autologous MSCs for treating the elderly population.

METHODS

Human bone marrow (BM)-derived MSCs from young and elderly donors were obtained and characterized using standard cell surface marker criteria (CD73, CD90, CD105) as recommended by the International Society for Cellular Therapy (ISCT). The elderly MSC population was isolated into four subpopulations based on size and stage-specific embryonic antigen-4 (SSEA-4) expression using fluorescence-activated cell sorting (FACS), and subpopulations were compared to the unfractionated young and elderly MSCs using assays that evaluate MSC proliferation, quality, morphology, intracellular reactive oxygen species, β-galactosidase expression, and adenosine triphosphate (ATP) content.

RESULTS

The ISCT-recommended cell surface markers failed to detect any differences between young and elderly MSCs. Here, we report that elderly MSCs were larger in size and displayed substantially higher concentrations of intracellular reactive oxygen species and β-galactosidase expression and lower amounts of ATP and SSEA-4 expression. Based on these findings, cell size and SSEA-4 expression were used to separate the elderly MSCs into four subpopulations by FACS. The original populations (young and elderly MSCs), as well as the four subpopulations, were then characterized before and after culture on tissue culture plastic and BM-derived extracellular matrix (BM-ECM). The small SSEA-4-positive subpopulation representing ~ 8% of the original elderly MSC population exhibited a "youthful" phenotype that was similar to that of young MSCs. The biological activity of this elderly subpopulation was inhibited by senescence-associated factors produced by the unfractionated parent population. After these "youthful" cells were isolated and expanded (three passages) on a "young microenvironment" (i.e., BM-ECM produced by BM cells from young donors), the number of cells increased ≈ 17,000-fold to 3 × 10⁹ cells and retained their "youthful" phenotype.

CONCLUSIONS

These results suggest that it is feasible to obtain large numbers of high-quality autologous MSCs from the elderly population and establish personal stem cell banks that will allow serial infusions of "rejuvenated" MSCs for treating age-related diseases.

Umbilical cord blood-derived non-hematopoietic stem cells retrieved and expanded on bone marrow-derived extracellular matrix display pluripotent characteristics

BACKGROUND

Umbilical cord blood (UCB) not only contains hematopoietic stem cells (HSCs), but also non-hematopoietic stem cells (NHSCs) that are able to differentiate into a number of distinct cell types. Based on studies published to date, the frequency of NHSCs in UCB is believed to be very low. However, the isolation of these cells is primarily based on their adhesion to tissue culture plastic surfaces.

METHODS AND RESULTS

In the current study, we demonstrate that this approach overlooks some of the extremely immature NHSCs because they lack the ability to adhere to plastic. Using a native extracellular matrix (ECM), produced by bone marrow (BM) stromal cells, the majority of the UCB-NHSCs attached within 4 h. The colony-forming unit fibroblast frequency of these cells was 1.5 × 10⁴/10⁸ mononuclear cells, which is at least 4000-fold greater than previously reported for UCB-NHSCs. The phenotype of these cells was fibroblast-like and different from those obtained by plastic adhesion; they formed embryonic body-like clusters that were OCT4-positive and expressed other human embryonic stem cell-related markers. Importantly, when implanted subcutaneously for 8 weeks into immunocompromised mice, these ECM-adherent and expanded NHSCs generated three germ layer-derived human tissues including muscle, fat, blood vessel, bone, gland, and nerve. Moreover, injection of these cells into muscle damaged by cryoinjury significantly accelerated muscle regeneration.

CONCLUSIONS

These results indicate that UCB may be a virtually unlimited source of NHSCs when combined with isolation and expansion on ECM. NHSCs may be a practical alternative to embryonic stem cells for a number of therapeutic applications.

Calculation of the Hadronic Vacuum Polarization Disconnected Contribution to the Muon Anomalous Magnetic Moment

We report the first lattice QCD calculation of the hadronic vacuum polarization (HVP) disconnected contribution to the muon anomalous magnetic moment at physical pion mass. The calculation uses a refined noise-reduction technique that enables the control of statistical uncertainties at the desired level with modest computational effort. Measurements were performed on the 48^{3}×96 physical-pion-mass lattice generated by the RBC and UKQCD Collaborations. We find the leading-order hadronic vacuum polarization a_{μ}^{HVP(LO)disc}=-9.6(3.3)(2.3)×10^{-10}, where the first error is statistical and the second systematic.

Native extracellular matrix preserves mesenchymal stem cell "stemness" and differentiation potential under serum-free culture conditions

Introduction

Bone marrow-derived mesenchymal stem cells (BM-MSCs) for clinical use should not be grown in media containing fetal bovine serum (FBS), because of serum-related concerns over biosafety and batch-to-batch variability. Previously, we described the preparation and use of a cell-free native extracellular matrix (ECM) made by bone marrow cells (BM-ECM) which preserves stem cell properties and enhances proliferation. Here, we compare colony-forming ability and differentiation of MSCs cultured on BM-ECM with a commercially available matrix (CELLstart™) and tissue culture plastic (TCP) under serum-free conditions.

Methods

Primary MSCs from freshly isolated bone marrow-derived mononuclear cells or passaged MSCs (P1) were grown in serum-containing (SCM) or serum-free (SFM) media on BM-ECM, CELLstart™, or TCP substrates. Proliferation, cell composition (phenotype), colony-forming unit replication, and bone morphogenetic protein-2 (BMP-2) responsiveness were compared among cells maintained on the three substrates.

Results

Proliferation of primary BM-MSCs was significantly higher in SCM than SFM, irrespectively of culture substrate, suggesting that the expansion of these cells requires SCM. In contrast, passaged cells cultured on BM-ECM or CELLstart™ in SFM proliferated to nearly the same extent as cells in SCM. However, morphologically, those on BM-ECM were smaller and more aligned, slender, and long.

Cells grown for 7 days on BM-ECM in SFM were 20–40 % more positive for MSC surface markers than cells cultured on CELLstart™. Cells cultured on TCP contained the smallest number of cells positive for MSC markers. MSC colony-forming ability in SFM, as measured by CFU-fibroblasts, was increased 10-, 9-, and 2-fold when P1 cells were cultured on BM-ECM, CELLstart™, and TCP, respectively. Significantly, CFU-adipocyte and -osteoblast replication of cells grown on BM-ECM was dramatically increased over those on CELLstart™ (2X) and TCP (4-7X). BM-MSCs, cultured in SFM and treated with BMP-2, retained their differentiation capacity better on BM-ECM than on either of the other two substrates.

Conclusions

Our findings indicate that BM-ECM provides a unique microenvironment that supports the colony-forming ability of MSCs in SFM and preserves their stem cell properties. The establishment of a robust culture system, combining native tissue-specific ECM and SFM, provides an avenue for preparing significant numbers of potent MSCs for cell-based therapies in patients.

Risk factors associated with anemia among Serbian non-pregnant women 20 to 49 years old. A cross-sectional study

BACKGROUND

Representative national data of prevalence of anemia and casual factors are missing for population group of reproductive aged non-pregnant females in Serbia. The purpose of the current study was to assess the prevalence and grades of anemia and its association with risk factors among non-pregnant women of childbearing age in Serbia.

METHODS

Data were collected as part of the first "National Health Survey", a cross-sectional, multistage cluster survey, conducted on 677 households in Serbia. A total of 708 females 20-49-year-old were recruited. Socioeconomic, anthropometric, dietary and reproductive data have been collected and hemoglobin levels were determined.

RESULTS

The overall prevalence of anemia was 27.7% (196/708) [95% Confidence Interval (CI), 24.5-31.1%], and more precisely mild (21.9%), moderate (5.1%) and severe (0.7%) anemia. Belgrade residential area [odds ratio 2.11 (95% CI 1.27-3.50), p=0.004], shortage of living space per person (<16m(2)) [2.18 (1.17-4.03), p=0.014], body mass index (<25) [1.55 (1.04-2.29), p=0.029], alcohol intake [0.52 (0.33-0.81), p=0.004], lack [2.48 (1.31-4.70), p=0.005] or fruit juice consumption 1-2 [2.76 (1.46-5.23), p=0.002] times a week and previously diagnosed, but treated [2.62 (1.29-5.35), p=0.008] or not treated [3.57 (1.71-7.45), p<0.001] anemia were independent predictors of low hemoglobin levels. Deficit of electricity supply and insufficient living space in households, increased risk of moderate anemia, while likelihood of being mild and moderately anemic, augmented with previously diagnosed but, treated or not treated anemia and lack or juice consumption 1-2 times a week.

CONCLUSIONS

High prevalence of anemia among non-pregnant women and its association to casual factors needs continuous monitoring and control efforts for anemia in Serbia.

Targeted gene inactivation reveals a functional role of calpain-1 in platelet spreading

BACKGROUND

Calpains are implicated in a wide range of cellular functions including the maintenance of hemostasis via the regulation of cytoskeletal modifications in platelets.

OBJECTIVES

Determine the functional role of calpain isoforms in platelet spreading.

METHODS AND RESULTS

Platelets from calpain-1(-/-) mice show enhanced spreading on collagen- and fibrinogen-coated surfaces as revealed by immunofluorescence, differential interference contrast (DIC) and scanning electron microscopy. The treatment of mouse platelets with MDL, a cell permeable inhibitor of calpains 1/2, resulted in increased spreading. The PTP1B-mediated enhanced tyrosine dephosphorylation in calpain-1(-/-) platelets did not fully account for the enhanced spreading as platelets from the double knockout mice lacking calpain-1 and PTP1B showed only a partial rescue of the spreading phenotype. In non-adherent platelets, proteolysis and GTPase activity of RhoA and Rac1 were indistinguishable between the wild-type (WT) and calpain-1(-/-) platelets. In contrast, the ECM-adherent calpain-1(-/-) platelets showed higher Rac1 activity at the beginning of spreading, whereas RhoA was more active at later time points. The ECM-adherent calpain-1(-/-) platelets showed an elevated level of RhoA protein but not Rac1 and Cdc42. Proteolysis of recombinant RhoA, but not Rac1 and Cdc42, indicates that RhoA is a calpain-1 substrate in vitro.

CONCLUSIONS

Potentiation of the platelet spreading phenotype in calpain-1(-/-) mice suggests a novel role of calpain-1 in hemostasis, and may explain the normal bleeding time observed in the calpain-1(-/-) mice.

[Diagnostic image (299). An oncology patient suffering from conjunctivitis]

A 64-year-old man with a small-cell bronchus carcinoma and metastases was treated with chemotherapy and developed conjunctivitis and necrosis of the eyelids caused by Pseudomonas aeruginosa.

[Eye complaints indicative of a tumor elsewhere in the body]

A variety of clinical presentations of malignant tumour metastases outside of the eye and orbit, were seen in four patients: a 52-year-old man who was scheduled to have a surgical removal of an oesophageal carcinoma and who presented with retinal detachment, a 58-year-old woman in whom retinopathy was the first sign of a cervical carcinoma (cancer-associated retinopathy), a 71-year-old man who had been treated for colon carcinoma and who presented with an orbital mass, and finally a 67-year-old woman with an orbital mass as the first sign of a Grawitz tumour. Metastasis should be considered in patients with a history of malignancy, who present with ophthalmologic complaints. Further it should be borne in mind that eye problems can be the first sign of oncological disease outside the eye.

Prognosis in monoclonal gammopathy of undetermined significance

Eighty-seven patients with monoclonal gammopathy of undetermined significance (MGUS) were followed for a period of 1-20 years, median 91 months. Transformation to multiple myeloma occurred in 14 patients of whom seven died as a consequence of the disease. There were 13 unrelated deaths. The actuarial probability of survival was 80% at 10 years and 44% at 15 years and the probabilities of malignant conversion for the same periods were 17% and 30% respectively. The most significant factor influencing the probability of malignant conversion was the increase of monoclonal protein above the level of 30 g/l during the observation period (P<0.001), followed by an increase of M-protein to more than 50% above the baseline level (P=0.02) and a decreased level of uninvolved immunoglobulins (P=0.054).

Localized hypertrichosis associated with periorbital neurofibroma: clinical findings and differential diagnosis

BACKGROUND

Congenital localized hypertrichosis in the periorbital region is an uncommon finding. The authors report two patients with hypertrichosis and cutaneous hyperpigmentation overlying a periorbital neurofibroma.

METHODS

In addition to a complete ophthalmic and systemic examination, the patients underwent computed tomography of the head and biopsy of the tumor.

RESULTS

Case 1 previously had received a diagnosis of neurofibromatosis type I. On examination, hyperpigmentation, hypertrichosis, and swelling in the right supraorbital region were noted. A computed tomographic scan showed a tumor in the same region. The tumor was removed, and a plexiform neurofibroma was diagnosed. Case 2 was admitted with hyperpigmentation, hypertrichosis, and swelling of the left half of her face. Other signs of neurofibromatosis were absent. A computed tomographic scan showed a tumor, which was underlying the skin changes. Results of histologic examination of the biopsy specimen showed a plexiform neurofibroma.

CONCLUSION

Neurofibroma-associated hypertrichosis should be considered in the differential diagnosis of congenital localized hypertrichosis.