Transient receptor potential vanilloid 4 regulates extracellular matrix composition and mediates load-induced intervertebral disc degeneration in a mouse model.

OBJECTIVE: Transient receptor potential vanilloid 4 (TRPV4) is a multi-modally activated cation channel that mediates mechanotransduction pathways by which musculoskeletal tissues respond to mechanical load and regulate tissue health. Using conditional Trpv4 knockout mice, we investigated the role of Trpv4 in regulating intervertebral disc (IVD) health and injury-induced IVD degeneration. METHODS: Col2-Cre;Trpv4fl/f (Trpv4 KO) mice were used to knockout Trpv4 in all type 2 collagen-expressing cells. Effects of gene targeting alone was assessed in lumbar spines, using vertebral bone length measurement, histological, immunohistochemistry and gene expression analyses, and mechanical testing. Disc puncture was performed on caudal IVDs of wild-type (WT) and Trpv4 KO mice at 2.5- and 6.5-months-of-age. Six weeks after puncture (4- and 8-months-of-age at sacrifice), caudal spines were assessed using histological analyses. RESULTS: While loss of Trpv4 did not significantly alter vertebral bone length and tissue histomorphology compared to age-matched WT mice, Trpv4 KO mice showed decreased proteoglycan and PRG4 staining in the annulus fibrosus compared to WT. At the gene level, Trpv4 KO mice showed significantly increased expression of Acan, Bgn, and Prg4 compared to WT. Functionally, loss of Trpv4 was associated with significantly increased neutral zone length in lumbar IVDs. Following puncture, both Trpv4 KO and WT mice showed similar signs of degeneration at the site of injury. Interestingly, loss of Trpv4 prevented mechanically-induced degeneration in IVDs adjacent to sites of injury. CONCLUSION: These studies suggest a role for Trpv4 in regulating extracellular matrix synthesis and mediating the response of IVD tissues to mechanical stress.

National survey conducted among Italian pediatricians examining the therapeutic management of croup.

OBJECTIVES: Practice-to-recommendations gaps exist in croup management and have not been critically investigated. This study examined the therapeutic management of croup among a national sample of Italian pediatric providers. METHODS: A survey was administered online to a sample of primary care and hospital-based pediatricians. Demographic data, perception regarding disease severity, treatment and knowledge of croup, choices of croup treatment medications, and knowledge of and adherence to treatment recommendations were compared between hospital and primary care pediatricians. Oral corticosteroids alone, oral corticosteroids with or without nebulized epinephrine and nebulized epinephrine plus oral or inhaled corticosteroids were considered the correct management in mild, moderate and severe croup, respectively. The determinants for correct management were examined using multivariate logistic regression analysis. RESULTS: Six hundred forty-nine pediatricians answered at least 50% of the survey questions and were included in the analysis. Providers reported extensive use of inhaled corticosteroids for mild and moderate croup. Recommended treatment for mild, moderate and severe croup was administered in 46/647 (7.1%), 181/645 (28.0%) and 263/643 (40.9%) participants, respectively. Provider's age and knowledge of Westley Croup Score were significant predictors for correct management of mild croup. Being a hospital pediatrician and perception of croup as a clinically relevant condition were significant for moderate croup. CONCLUSIONS: Significant differences exist between recommended guidelines and clinical practice in croup management. This study suggests wide variability in both the treatment of croup and clinical decision making strategies among hospital and primary care pediatricians. Addressing this issue could lead to noteworthy clinical and economic benefits.

Maximizing the potential value of the nursing workforce.

This panel paper is the fifth installment in a six-part Nursing Outlook special edition based on the 2022 Emory Business Case for Nursing Summit. The 2022 summit convened national nursing, health care, and business leaders to explore possible solutions to nursing workforce crises, including the nursing shortage. Each of the summit's four panels authored a paper in this special edition on their respective topic, and this panel paper focuses on maximizing the potential value of the nursing workforce. It addresses topics including the need to create a nursing-inclusive federal health care billing system improve nursing salaries by designing/testing nurse-informed compensation models, and strengthen nursing's national professional infrastructure.

End binding-3 inhibitor activates regenerative program in age-related macular degeneration.

Wet age-related macular degeneration (AMD), characterized by leaky neovessels emanating from the choroid, is a main cause of blindness. As current treatments for wet AMD require regular intravitreal injections of anti-vascular endothelial growth factor (VEGF) biologics, there is a need for the development of less invasive treatments. Here, we designed an allosteric inhibitor of end binding-3 (EB3) protein, termed EBIN, which reduces the effects of environmental stresses on endothelial cells by limiting pathological calcium signaling. Delivery of EBIN via eye drops in mouse and non-human primate (NHP) models of wet AMD prevents both neovascular leakage and choroidal neovascularization. EBIN reverses the epigenetic changes induced by environmental stresses, allowing an activation of a regenerative program within metabolic-active endothelial cells comprising choroidal neovascularization (CNV) lesions. These results suggest the therapeutic potential of EBIN in preventing the degenerative processes underlying wet AMD.

A Novel Device for Suprachoroidal Drug Delivery to Retina: Evaluation in Nonhuman Primates.

Purpose: Evaluation of distribution and tolerance of suprachoroidal injection of indocyanine green (ICG) in nonhuman primates (NHPs) using a novel suprachoroidal (SC) delivery technology. Methods: Three live and three euthanized African green monkeys were injected with 150 or 200 µL ICG/eye into the SC space of both eyes, 2.5 mm posterior to the limbus in the inferior quadrant, utilizing a novel SC injector. Eyes were analyzed by imaging of scleral flatmounts. Live animals were observed for 24 hours for general health. Ophthalmic evaluation included slit-lamp biomicroscopy, tonometry, fundus imaging, confocal laser ophthalmoscopy, and spectral-domain optical coherence tomography (SD-OCT) before and at 10 minutes and 1, 3, and 24 hours post-injection. Results: SC dosing was successfully performed in all eyes. Infrared fundus imaging demonstrated ICG distribution throughout the posterior segment, reaching the macula within 24 hours post-injection. No inflammation, intravitreal penetration, SC blebs, retinal detachment, or hemorrhages were detected. No significant changes were observed in retinal thickness by SD-OCT (P = 0.267, ANOVA). A mild, statistically insignificant elevation in intraocular pressure was observed within 10 minutes post-injection (mean ± standard error: 7.28 ± 5.09 mmHg; P = 0.061) and was spontaneously resolved within the first hour after dosing. Conclusions: Suprachoroidal injection of 150 to 200 µL ICG dye was successfully performed and well tolerated in NHP eyes, with rapid distribution into the macular region and throughout the posterior pole. Translational Relevance: This novel SC drug delivery system may potentially provide safe and effective delivery of therapeutics to the posterior pole region in humans.

A comparative study into the effects of venous and arterial blood on clot microstructure in critically unwell patients. Assessment of the diagnostic potential of a biomarker of haemostasis.

Blood for coagulation analysis can be sampled from the arterial or venous system in intensive care units (ICU). The determination of clot microstructure and strength by fractal analysis (df) gives valuable information in a range of vascular haemostatic disease and sepsis. We aimed to determine if df could be measured equally and comparatively in arterial or venous blood, and 45 critically ill patients in an ICU were recruited. df was found to be readily measured in arterial blood with results comparable to those in venous blood and that add value of df as a potential marker of haemostasis in these patients.

Naturally occurring histological findings and Alzheimer's-like pathology in the brain of aging African green monkeys (Chlorocebus sabaeus).

Nonhuman primates (NHPs) are important to study the pathophysiology of neurodegenerative disease and evaluate therapies targeting the central nervous system (CNS). Understanding the age-associated incidence of natural CNS pathology in a given NHP species is critical to assess the safety of potential treatments for neurodegenerative disorders like Alzheimer's disease (AD). We describe background and age-related neuropathology in the St. Kitts African green monkey (AGM), a recognized translational model for neurodegenerative research, additionally defining the age progression of AD-associated neuropathology in this species. Seventy-one AGM brains were examined, representing age groups of 3-6 years (n = 20), 7-9 years (n = 20), 10-15 years (n = 20), and >15 years (n = 11). A subset of brains (n = 31) was assessed immunohistochemically for AD-related pathology, including expressions of Aß, tau, and GFAP. Age-related microscopic findings included hemosiderosis, spheroid formation, neuronal lipofuscinosis and neuromelanosis, white matter and neuropil vacuolation, astrocytosis, and focal microgliosis. Non-age-related findings included perivascular ceroid-laden macrophages, meningeal melanosis, and vascular mineralization. Immunohistochemistry revealed 4G8-immunopositive Aß plaques and vascular deposits in the prefrontal, frontal, cingulate, and temporal cortices of nine animals over 15 years of age, with associated increase in GFAP expression. In 12 animals, 11 over the age of 10 years, phosphorylated tau CP13-immunoreactive neurons, neuropil, and oligodendrocyte-like cells were seen in the prefrontal, frontal, cingulate, orbital, temporal, and entorhinal cortices as well as the hippocampus; no neurofibrillary tangles were observed. AD-related pathology showed an age-related development in cognitive-associated areas in the AGM, highlighting the value of the AGM as a natural model for these neurodegenerative diseases.

Cardiac Cachexia in Left Ventricular Assist Device Recipients and the Implications of Weight Gain Early After Implantation.

Background Severe cardiac cachexia or malnutrition are commonly considered relative contraindications to left ventricular assist device (LVAD) implantation, but post-LVAD prognosis for patients with cachexia is uncertain. Methods and Results Intermacs (Interagency Registry for Mechanically Assisted Circulatory Support) 2006 to 2017 was queried for the preimplantation variable cachexia/malnutrition. Cox proportional hazards modeling examined the relationship between cachexia and LVAD outcomes. Of 20 332 primary LVAD recipients with available data, 516 (2.54%) were reported to have baseline cachexia and had higher risk baseline characteristics. Cachexia was associated with higher mortality during LVAD support (unadjusted hazard ratio [HR], 1.36 [95% CI, 1.18-1.56]; P<0.0001), persisting after adjustment for baseline characteristics (adjusted HR, 1.23 [95% CI, 1.0-1.42]; P=0.005). Mean weight change at 12 months was +3.9±9.4 kg. Across the cohort, weight gain ≥5% during the first 3 months of LVAD support was associated with lower mortality (unadjusted HR, 0.90 [95% CI, 0.84-0.98]; P=0.012; adjusted HR, 0.89 [95% CI, 0.82-0.97]; P=0.006). Conclusions The proportion of LVAD recipients recognized to have cachexia preimplantation was low at 2.5%. Recognized cachexia was independently associated with higher mortality during LVAD support. Early weight gain ≥5% was independently associated with lower mortality during subsequent LVAD support.

Tolerability and tropism of recombinant adeno-associated virus vectors in the African green monkey (Chlorocebus sabaeus) anterior chamber.

While many studies have investigated the use of recombinant adeno-associated vectors (rAAV) in the posterior chamber for treatment of inherited retinal diseases, fewer studies have looked at rAAV's ability to transduce cells within the anterior chamber. This study focuses on evaluating the tropism and tolerability of three rAAV serotypes-rAAV2/6, rAAV2/9, and rAAV2/2[MAX]-expressing a green fluorescent protein (GFP) reporter following intracameral injection in the non-human primate (NHP) African green monkey (Chlorocebus sabaeus) model. Injection of high dose (1 × 1012 vg/eye) rAAV vector resulted in transient inflammation characterized by aqueous flare and cellular infiltrate that resolved without intervention in all serotypes. Post-mortem histology revealed widespread expression of GFP in cells of the trabecular meshwork and iris in high dose rAAV2/6, rAAV2/9, and particularly rAAV2/2[MAX] eyes, indicating that rAAV vectors of these serotypes have broad tropism for cells of the anterior chamber and may facilitate the treatment of blinding disorders, such as glaucoma.

Matrix metalloproteinase-3 (MMP-3)-mediated gene therapy for glaucoma.

Approximately 80 million people globally are affected by glaucoma, with a projected increase to over 110 million by 2040. Substantial issues surrounding patient compliance remain with topical eye drops, and up to 10% of patients become treatment resistant, putting them at risk of permanent vision loss. The major risk factor for glaucoma is elevated intraocular pressure, which is regulated by the balance between the secretion of aqueous humor and the resistance to its flow across the conventional outflow pathway. Here, we show that adeno-associated virus 9 (AAV9)-mediated expression of matrix metalloproteinase-3 (MMP-3) can increase outflow in two murine models of glaucoma and in nonhuman primates. We show that long-term AAV9 transduction of the corneal endothelium in the nonhuman primate is safe and well tolerated. Last, MMP-3 increases outflow in donor human eyes. Collectively, our data suggest that glaucoma can be readily treated with gene therapy-based methods, paving the way for deployment in clinical trials.

The Impact of Patient Characteristics and Antiplatelet Regimes on Clot Microstructure in Patients Treated for ST Elevation Myocardial Infarction: Clot Microstructure can Evaluate Therapeutic Efficacy.

BACKGROUND: Unfavourable clot microstructure is associated with adverse outcomes in ST elevation myocardial infarction (STEMI). We investigated the effect of comorbidities and anti-platelet treatment on clot microstructure in STEMI patients using fractal dimension (df), a novel biomarker of clot microstructure derived from the visco-elastic properties of whole blood. METHODS: Patients with STEMI (n = 187) were recruited sequentially receiving aspirin with Clopidogrel (n = 157) then Ticagrelor (n = 30). Patient characteristics and blood for rheological analysis obtained. We quantified df using sequential frequency sweep tests to obtain the phase angle of the Gel Point which is synonymous with the clot microstructure. RESULTS: Higher df was observed in males (1.755 ± 0.068) versus females (1.719 ± 0.061, p = .001), in patients with diabetes (1.786 ± 0.067 vs 1.743 ± 0.046, p < .001), hypertension (1.760 ± 0.065 vs 1.738 ± 0.069, p = .03) and previous MI (1.787 ± 0.073 vs 1.744 ± 0.066, p = .011) compared to without. Patients receiving Ticagrelor had lower df than those receiving Clopidogrel (1.708 ± 0.060 vs 1.755 ± 0.067, p < .001). Significant correlation with df was found with haematocrit (r = 0.331, p < .0001), low-density lipoprotein (LDL) (r = 0.155, p = .046) and fibrinogen (r = 0.182, p = .014). Following multiple regression analysis, diabetes, LDL, fibrinogen and haematocrit remained associated with higher df while treatment with Ticagrelor remained associated with lower df. CONCLUSIONS: The biomarker df uniquely evaluates the effect of interactions between treatment and underlying disease on clot microstructure. STEMI patients with diabetes and elevated LDL had higher df, indicating denser clot. Ticagrelor resulted in a lower df than Clopidogrel signifying a less compact clot.

Assessment of a novel continuous cleaning device using metatranscriptomics in diverse hospital environments.

Introduction: Despite routine implementation of cleaning and disinfection practices in clinical healthcare settings, high-touch environmental surfaces and contaminated equipment often serve as reservoirs for the transmission of pathogens associated with healthcare-associated infections (HAIs). Methods: The current study involved the analysis of high-touch surface swabs using a metatranscriptomic sequencing workflow (CSI-Dx™) to assess the efficacy of cleanSURFACES® technology in decreasing microbial burden by limiting re-contamination. This is a non-human single center study conducted in the Emergency Department (ED) and on an inpatient Oncology Ward of Walter Reed National Military Medical Center that have followed hygienic practices during the COVID-19 pandemic environment. Results: Although there was no difference in observed microbial richness (two-tailed Wilcoxon test with Holm correction, P > 0.05), beta diversity findings identified shifts in microbial community structure between surfaces from baseline and post-intervention timepoints (Day 1, Day 7, Day 14, and Day 28). Biomarker and regression analyses identified significant reductions in annotated transcripts for various clinically relevant microorganisms' post-intervention, coagulase-negative staphylococci and Malassezia restricta, at ED and Oncology ward, respectively. Additionally, post-intervention samples predominantly consisted of Proteobacteria and to a lesser extent skin commensals and endogenous environmental microorganisms in both departments. Discussion: Findings support the value of cleanSURFACES®, when coupled with routine disinfection practices, to effectively impact on the composition of active microbial communities found on high-touch surfaces in two different patient care areas of the hospital (one outpatient and one inpatient) with unique demands and patient-centered practices.

Application of the COM-B Framework to Understand Facilitators and Barriers for Practising Physical Activity among Pregnant Women and Midwives Participating in the WELL-DONE! Study.

Regular physical activity (PA) is protective and reduces disease burden but remains a challenge for pregnant women (PW). According to the World Health Organization (WHO) guidelines, PW without contraindications should practice 150 min of moderate PA per week. Nonetheless, PA levels are concerningly low among PW. The aim of this study was to investigate PW's and midwives' perceptions regarding PA and recommended guidelines, and use this information to inform future health promotion strategies. We recruited 10 PW and 10 midwives to participate in online focus groups conducted between July 2020 and April 2021. Focus group probes and data analysis were guided by the COM-B (capability, opportunity, motivation-behaviour) framework. The majority of the sample had already practised PA, recognized the importance of PA during pregnancy, and considered the WHO guidelines reasonable. Notwithstanding, PW wanted more specific instruction on PA and desired opportunities to practice. Additional barriers reported by PW included low self-efficacy and lack of motivation. Midwives considered the lack of specific knowledge and confidence in managing PA as the main obstacles. The current findings suggest that PW and midwives need specific training in PA to overcome both psychological and physical barriers. Midwives play a vital role in educating and encouraging PA among PW.

The efficacy of low molecular weight heparin is reduced in COVID-19.

BACKGROUND: A significant degree of mortality and morbidity in COVID-19 is through thromboembolic complications, only partially mitigated by anticoagulant therapy. Reliable markers of infection severity are not fully established. OBJECTIVES: This study investigated whether visco-elastic biomarkers predict disease severity on presentation to the Emergency Department (ED) and how they measure response to anticoagulationMETHODS:Patients testing positive for COVID-19 at a large University Teaching Hospital ED were recruited at presentation. Multiple blood samples were taken throughout hospital admission to monitor disease progression with end outcome recorded. Visco-elastic markers, fractal dimension (df) and Time to Gel Point (TGP) which measure the properties of the incipient clot were compared in patients with and without anticoagulation by Low Molecular Weight Heparin (LMWH). RESULTS: TGP and df did not predict severity of infection with COVID-19. Although LMWH prolonged TGP, there was no change in df indicating LMWH did not change clot microstructure. CONCLUSIONS: Therapeutic efficacy of LMWH appears blunted in COVID-19 infection. This may be due to the inflammatory state creating a resistance to LMWH activity, which may explain why LMWH appears less effective in COVID-19 compared to other disease states. COVID-19 was not predicted by visco-elastic testing at the time of ED presentation.

Poor engagement and adherence predict neoplasia in inflammatory bowel disease: a case-control study.

BACKGROUND: Colorectal adenocarcinoma is an important and preventable complication of inflammatory bowel disease (IBD). A previous case series suggested mental health issues and poor engagement in care as novel risk factors. AIMS: To confirm the role of patient engagement in care in the development of neoplasia using a case-control methodology. METHODS: Patients in a single referral centre from 2007 to 2017 with colorectal adenocarcinoma, high-grade dysplasia or multifocal low-grade dysplasia were included as neoplasia cases. Each case was assigned up to three matched controls (matched for age, gender, underlying disease, IBD type and phenotype and disease duration). Novel and known risk factors were compared between groups. RESULTS: Thirty-two cases with 88 matched controls were included. Patients with neoplasia were more likely to have poor adherence to, or engagement with, care (odds ratio (OR) 4.79). They were also more likely to have chronic use of opioids (OR 3.86) and long-term prednisolone (OR 2.97). Of note, no difference was found in measures of socioeconomic disadvantage, reflecting equitable access to healthcare in the public institution where the care was studied. As previously shown, patients with neoplasia had multiple markers of increased cumulative burden of inflammation, including more IBD-related hospital admissions, elevated inflammatory markers and severe inflammation at colonoscopy. CONCLUSIONS: This study confirms poor adherence or engagement with care as a new risk factor for colorectal adenocarcinoma in patients with IBD; identifying a vulnerable group whom clinicians should endeavour to engage in order to avoid this catastrophic complication.

In the line of fire: Debris throwing by wild octopuses.

Wild Octopus tetricus frequently propel shells, silt, and algae through the water by releasing these materials from their arms while creating a forceful jet from the siphon held under the arm web. These "throws" occur in several contexts at a site in Jervis Bay, Australia, including in interactions with other octopuses. Material thrown in interactive contexts frequently hits other octopuses. Some throws appear to be targeted on other individuals, as suggested by several kinds of evidence: Throws in interactive contexts were more vigorous than others, and more often used silt, rather than shells or algae. High vigor throws were more often accompanied by uniform or dark body patterns than other throws. Some throws were directed differently from beneath the arms and such throws were more likely to hit other octopuses. Throwing at other individuals in the same population, as apparently seen in these octopuses, is a rare form of nonhuman projectile use, previously seen only in some social mammals.

Evaluation of the Dose-Dependent Inflammatory Response and No-Observable Adverse Effect Level of Intravitreal Endotoxin in the African Green Monkey.

Purpose: To evaluate the inflammatory effects and no-observed adverse effect level (NOAEL) of intravitreal endotoxin in an African green monkey model of uveitis. Methods: Fifteen green monkeys were administered intravitreal endotoxin ranging from 0.005 to 0.08 endotoxin unit (EU)/eye. Inflammation was evaluated by slit-lamp biomicroscopy, indirect fundoscopy, tonometry, color fundus photography, ocular coherence tomography, laser flare photometry, and histopathology, with analysis of cytokine levels in aqueous and vitreous humor. The inter-rater reliability of a refined nonhuman primate ophthalmic scoring system was evaluated. Results: A dose-dependent inflammatory response was observed beginning at 0.02 EU/eye; no inflammatory response exceeding the vehicle was observed at 0.005 EU/eye. Retinal pathology was minimal, and posterior visualization degraded with increasing inflammation. Inflammation was observed by histopathology at 0.04 EU/eye. Inter-rater reliability of the scoring system was high, with 99.2% of individual scores differing by 1 scale unit or less and 87.2% of summary scores differing by 2 scale units or less. Conclusions: The NOAEL for intravitreal endotoxin in the green monkey is 0.005 EU/eye, with inflammation increasing with increasing dose beginning at 0.02 EU/eye. This updated nonhuman primate ophthalmic scoring system allows for high inter-rater reliability for the quantification of mild to severe inflammation in the green monkey eye. Translational Relevance: Validation of the ophthalmic inflammation scoring system enables application of the green monkey as a valuable translational model. Candidate therapeutics should be confirmed to have endotoxin levels below this threshold before safety testing in this species to enable interpretation of inflammation and minimize impact on animal welfare.

Impaired fibrinolysis in severe Covid-19 infection is detectable in early stages of the disease.

BACKGROUND: A significant degree of mortality and morbidity in Covid-19 is due to thromboembolic disease. Coagulopathy has been well described in critically unwell patients on ICU. There is less clear evidence regarding these changes at the time of presentation to the Emergency Department and the progression of disease over time. OBJECTIVE: We sought to investigate whether coagulation markers can predict severity and how they change over the disease course. METHODS: Patients presenting to a single University Teaching Hospital were recruited and followed up if PCR was positive. Alongside routine blood testing, Rotational Thromboelastometry (ROTEM) was performed. Outcome data was recorded for all patients, and ROTEM values were compared across outcome groups. RESULTS: Extem and Intem Maximum Lysis were significantly reduced in those who died or required an ICU admission, indicating a reduced ability to break down clot mass in the most critically unwell patients. CONCLUSION: Comparisons between groups demonstrated that one distinguishing feature between those who require ICU admission or die of Covid-19 compared with those who survive a hospital stay to discharge was the extent to which fibrinolysis could occur. Mortality and morbidity in Covid-19 infection appears in part driven by an inability to break down clot mass.

Skeletal Muscle Mass Recovery Early After Left Ventricular Assist Device Implantation in Patients With Advanced Systolic Heart Failure.

BACKGROUND: Patients with advanced systolic heart failure are at risk of unintentional weight loss and muscle wasting. It has been observed that left ventricular assist device (LVAD) recipients gain weight after device implantation, although it is unknown whether this represents skeletal muscle mass gains. We aimed to determine whether skeletal muscle mass increases early during LVAD support. METHODS: We prospectively recruited 30 adults with systolic heart failure ±21 days from LVAD implantation. Participants underwent whole-body dual X-ray absorptiometry to measure fat free mass, appendicular lean mass (ALM, lean mass in the arms and legs) and fat mass. Dual X-ray absorptiometry imaging was repeated at 3 and 6 months after LVAD implantation, with participation ending after the 6-month visit or heart transplantation, whichever occurred first. Changes in body composition were evaluated using mixed effects linear regression models. RESULTS: The cohort was 87% male, with mean age 56±12 (SD) years, and mean body mass index 26.4±5.4 kg/m2. Per sarcopenia ALM criteria, 52% of participants had muscle wasting at baseline. At baseline, mean fat free mass and ALM were 56.4±11.7 and 21.0±5.3 kg, respectively. Both measures increased significantly (P<0.001) over 6 months of LVAD support: mean fat free mass change at 3 and 6 months: 2.3 kg (95% CI, 1.0-3.5) and 4.2 kg (95% CI, 2.2-6.1); mean ALM change at 3 and 6 months: 1.5 kg (95% CI, 0.7-2.3) and 2.3 kg (95% CI, 0.9-3.6). CONCLUSIONS: Among LVAD recipients with advanced systolic heart failure and high baseline prevalence of muscle wasting, there were significant gains in skeletal muscle mass, as represented by dual X-ray absorptiometry fat free mass and ALM, over the first 6 months of LVAD support.

The effects of apixaban on clot characteristics in atrial fibrillation: A novel pharmacodynamic biomarker.

Atrial fibrillation (AF) is a major risk factor for stroke. We aim to characterize AF patients and the effects of apixaban therapy in terms of clot microstructure using gel point analysis, a novel biomarker. Seventy-eight patients were included in the study, 50 Stroke with AF (AF-S), and 28 AF without stroke (AF). Pre- and post-anticoagulation samples were collected: gel point (GP) analysis was performed to obtain (i) TGP (the time taken to reach the GP or the clot formation time) and (ii) df, the fractal dimension of the clot, a quantification of clot fibrin microstructure at the GP. At baseline, the AF-S group had a df  = 1.70 (±0.05) and TGP = 306 (±73 s). The AF group had a df = 1.70 ± 0.05 and TGP = 346 ± 78 s, showing a significantly shortened TGP in the stroke group (p = .008). For both groups, apixaban significantly prolonged TGP, p = .005, but resulted in no change in df. Apixaban prolonged clotting time while having no significant impact on the blood's ability to form stable clots (no change in df ). This indicates that apixaban provides protection from the formation of thrombi by reducing clotting kinetics.