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1.
Article in English | MEDLINE | ID: mdl-38933471

ABSTRACT

Machine learning at the extreme edge has enabled a plethora of intelligent, time-critical, and remote applications. However, deploying interpretable artificial intelligence systems that can perform high-level symbolic reasoning and satisfy the underlying system rules and physics within the tight platform resource constraints is challenging. In this paper, we introduce TinyNS, the first platform-aware neurosymbolic architecture search framework for joint optimization of symbolic and neural operators. TinyNS provides recipes and parsers to automatically write microcontroller code for five types of neurosymbolic models, combining the context awareness and integrity of symbolic techniques with the robustness and performance of machine learning models. TinyNS uses a fast, gradient-free, black-box Bayesian optimizer over discontinuous, conditional, numeric, and categorical search spaces to find the best synergy of symbolic code and neural networks within the hardware resource budget. To guarantee deployability, TinyNS talks to the target hardware during the optimization process. We showcase the utility of TinyNS by deploying microcontroller-class neurosymbolic models through several case studies. In all use cases, TinyNS outperforms purely neural or purely symbolic approaches while guaranteeing execution on real hardware.

2.
Aging Dis ; 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38502583

ABSTRACT

The cerebellum plays a vital role in the aging process. With the aging of the cerebellum, there is a decline in balance and motor function, particularly fine motor skills, and an increased risk of falling. However, in recent years, numerous studies have revealed that the cerebellum has several roles beyond balance and fine motor skills, such as cognitive function and memory. It also plays a role in many neurodegenerative diseases. Interestingly, the cerebellum ages more rapidly than other brain regions, including the hippocampus. With increasing studies reporting that the cerebellum has a more prominent and interconnected role in the brain, it is essential to understand why aging affects it more, leading to solutions to help curb the accelerated decline. Here, we summarize the cerebellum's function and look at how it ages at the cellular, molecular, and functional levels. Additionally, we explore the the effects of alcoholism on the aging cerebellum as well as the role of the cerebellum in diseases such as Alzheimer's, Parkinson's, and Multiple Sclerosis.

3.
Article in English | MEDLINE | ID: mdl-38372028

ABSTRACT

KEY POINTS: Severe epistaxis occurs in 2% of PNN ablation cases, independent of method or device type. Major epistaxis requiring intervention after PNN ablation can occur on average 20 days post-procedure.

4.
Clin Cardiol ; 47(1): e24209, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38269636

ABSTRACT

Transcatheter aortic valve replacement (TAVR) has emerged as a ground-breaking, minimally invasive alternative to traditional open-heart surgery, primarily designed for elderly patients initially considered unsuitable for surgical intervention due to severe aortic stenosis. As a result of successful large-scale trials, TAVR is now being routinely applied to a broader spectrum of patients. In deciding between TAVR and surgical aortic valve replacement, clinicians evaluate various factors, including patient suitability and anatomy through preprocedural imaging, which guides prosthetic valve sizing and access site selection. Patient surgical risk is a pivotal consideration, with a multidisciplinary team making the ultimate decision in the patient's best interest. Periprocedural imaging aids real-time visualization but is influenced by anaesthesia choices. A comprehensive postprocedural assessment is critical due to potential TAVR-related complications. Numerous trials have demonstrated that TAVR matches or surpasses surgery for patients with diverse surgical risk profiles, ranging from extreme to low risk. However, long-term follow-up data, particularly in low-risk cases, remains limited, and the applicability of published results to younger patients is uncertain. This review delves into key TAVR studies, pinpointing areas for potential improvement while delving into the future of this innovative procedure. Furthermore, it explores the expanding role of TAVR technology in addressing other heart valve replacement procedures.


Subject(s)
Transcatheter Aortic Valve Replacement , Humans
5.
J Affect Disord ; 329: 293-299, 2023 05 15.
Article in English | MEDLINE | ID: mdl-36858267

ABSTRACT

INTRODUCTION: Anxiety disorders are a prevalent and severe problem that are often developed early in life and can disrupt the daily lives of affected individuals for many years into adulthood. Given the persistent negative aspects of anxiety, accurate and early assessment is critical for long term outcomes. Currently, the most common method for anxiety assessment is through point-in-time measures like the GAD-7. Unfortunately, this survey and others like it can be subject to recall bias and do not fully capture the variability in an individual's day-to-day symptom experience. The current work aims to evaluate how point-in-time assessments like the GAD-7 relate to daily measurements of anxiety in a teenage population. METHODS: To evaluate this relationship, we leveraged data collected at four separate three week intervals from 30 teenagers (age 15-17) over the course of a year. The specific items of interest were a single item anxiety severity measure collected three times per day and end-of-month GAD-7 assessments. Within this sample, 40 % of individuals reported clinical levels of generalized anxiety disorder symptoms at some point during the study. The first component of analysis was a visual inspection assessing how daily anxiety severity fluctuated around end-of-month reporting via the GAD-7. The second component was a between-subjects comparison assessing whether individuals with similar GAD-7 scores experienced similar symptom dynamics across the month as represented by latent features derived from a deep learning model. With this approach, similarity was operationalized by hierarchical clustering of the latent features. RESULTS: The aim clearly indicated that an individual's daily experience of anxiety varied widely around what was captured by the GAD-7. Additionally, when hierarchical clustering was applied to the three latent features derived from the (LSTM) encoder (r = 0.624 for feature reconstruction), it was clear that individuals with similar GAD-7 outcomes were experiencing different symptom dynamics. Upon further inspection of the latent features, the LSTM model appeared to rely as much on anxiety variability over the course of the month as it did on anxiety severity (p < 0.05 for both mean and RMSSD) to represent an individual's experience. DISCUSSION: This work serves as further evidence for the heterogeneity within the experience of anxiety and that more than just point-in-time assessments are necessary to fully capture an individual's experience.


Subject(s)
Deep Learning , Humans , Adolescent , Anxiety Disorders/diagnosis , Anxiety Disorders/epidemiology , Anxiety/diagnosis , Anxiety/epidemiology , Surveys and Questionnaires
6.
J Perioper Pract ; 33(12): 396-400, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36635887

ABSTRACT

INTRODUCTION: de Garengeot's hernias occur when an inflamed appendix is encased within a femoral sac. This is a relatively rare type of femoral hernia. As a result, there are currently no guidelines for the management of these hernias. CASE: We present a 90-year-old woman with a de Garengeot's hernia complicated with strangulation and perforation. The diagnosis was made intraoperatively, and it was managed with hernia repair and an appendicectomy. There were no postoperative complications. DISCUSSION: The presentation of de Garengeot's hernias is non-specific. Enclosure of the bowel content within the hernia sac may mask systemic systems of disease. Rarely, septic signs or symptoms are identified on presentation. It is typically diagnosed intraoperatively, thus prompt emergency surgery should not be delayed by clinicians awaiting precise knowledge of the sac content via imaging. Prompt surgery with a single McEvedy incision enables treatment for both the appendicitis and abdominal wall defect, an appendectomy and hernia repair, respectively. In patients that present with an irreducible femoral hernia and biochemistry suggestive of an acute inflammatory process, there should be a high clinical suspicion for de Garengeot's hernia due to the risk of perforation being masked by an anatomical encasement around the perforated bowel content.


Subject(s)
Appendicitis , Appendix , Hernia, Femoral , Female , Humans , Aged, 80 and over , Hernia, Femoral/complications , Hernia, Femoral/diagnostic imaging , Hernia, Femoral/surgery , Appendix/surgery , Appendectomy/methods , Appendicitis/complications , Appendicitis/diagnostic imaging , Appendicitis/surgery , Herniorrhaphy/methods
7.
J Spine Surg ; 9(4): 493-498, 2023 Dec 25.
Article in English | MEDLINE | ID: mdl-38196726

ABSTRACT

Background: A cervical laminoplasty is a surgical procedure used to treat moderate-to-severe cervical stenosis resulting in cervical myelopathy. It is performed to widen the spinal canal and reduce compression on the spinal cord and surrounding nerves. Though often performed electively on patients presenting with varying degrees of neurologic dysfunction including weakness and imbalance, it may also be used prophylactically when spinal cord inflammation or edema is anticipated. Radiotherapy in the spinal cord is known to produce radiation-induced damage leading to radiation myelopathy. Case Description: We present the case of a 62-year-old male diagnosed with both cervical stenosis and an intramedullary cervical spinal cord metastatic tumor. This patient presented with significant symptoms including limited mobility, numbness, lower back pain, paresthesia, and spasms in both legs as well as worsening sexual function. Given that the patient was to undergo radiotherapy, a cervical laminoplasty was performed to eliminate ongoing spinal cord compression as well to prevent future neurologic decline resulting from post-radiation inflammation and edema. Conclusions: This case highlights that cervical laminoplasty can be performed safely and effectively with significant improvement in patients with metastatic disease. By treating the underlying symptomatic stenosis, and protect the patient from the potential for spinal cord edema from radiation to a spinal cord lesion in an already narrow spinal canal.

8.
J Am Chem Soc ; 144(46): 21398-21407, 2022 11 23.
Article in English | MEDLINE | ID: mdl-36346461

ABSTRACT

Chemical synthesis of natural products is typically inspired by the structure and function of a target molecule. When both factors are of interest, such as in the case of taxane diterpenoids, a synthesis can both serve as a platform for synthetic strategy development and enable new biological exploration. Guided by this paradigm, we present here a unified enantiospecific approach to diverse taxane cores from the feedstock monoterpenoid (S)-carvone. Key to the success of our approach was the use of a skeletal remodeling strategy which began with the divergent reorganization and convergent coupling of two carvone-derived fragments, facilitated by Pd-catalyzed C-C bond cleavage tactics. This coupling was followed by additional restructuring using a Sm(II)-mediated rearrangement and a bioinspired, visible-light induced, transannular [2 + 2] photocycloaddition. Overall, this divergent monoterpenoid remodeling/convergent fragment coupling approach to complex diterpenoid synthesis provides access to structurally disparate taxane cores which have set the stage for the preparation of a wide range of taxanes.


Subject(s)
Monoterpenes , Taxoids , Stereoisomerism
9.
Front Oncol ; 12: 945689, 2022.
Article in English | MEDLINE | ID: mdl-36203435

ABSTRACT

Malignant tumors of the digestive system are common worldwide; however, it is extremely rare for more than two malignancies to occur simultaneously. Here, we report a case with a triple malignancy of the digestive system, including gastric, rectal, and hepatic tumors. The patient underwent surgical resection of three tumors followed by chemotherapy. Negative image-based screenings and the absence of serum tumor biomarkers elevation were found at 2.5 years after the surgery, indicating the absence of recurrence and metastasis of cancers.

10.
J Alzheimers Dis ; 90(2): 543-551, 2022.
Article in English | MEDLINE | ID: mdl-36155511

ABSTRACT

We examined amyloid-tau-neurodegeneration biomarker effects on cognition in a Southeast-Asian cohort of 84 sporadic young-onset dementia (YOD; age-at-onset <65 years) patients. They were stratified into A+N+, A- N+, and A- N- profiles via cerebrospinal fluid amyloid-ß1-42 (A), phosphorylated-tau (T), MRI medial temporal atrophy (neurodegeneration- N), and confluent white matter hyperintensities cerebrovascular disease (CVD). A, T, and CVD effects on longitudinal Mini-Mental State Examination (MMSE) were evaluated. A+N+ patients demonstrated steeper MMSE decline than A- N+ (ß = 1.53; p = 0.036; CI 0.15:2.92) and A- N- (ß = 4.68; p = 0.001; CI 1.98:7.38) over a mean follow-up of 1.24 years. Within A- N+, T- CVD+ patients showed greater MMSE decline compared to T+CVD- patients (ß = - 2.37; p = 0.030; CI - 4.41:- 0.39). A+ results in significant cognitive decline, while CVD influences longitudinal cognition in the A- sub-group.


Subject(s)
Alzheimer Disease , Amyloidosis , Cardiovascular Diseases , Cognitive Dysfunction , Dementia , Humans , Alzheimer Disease/psychology , Amyloid , Amyloid beta-Peptides , Biomarkers , Cognition , Cognitive Dysfunction/diagnostic imaging , Dementia/diagnostic imaging , tau Proteins , Middle Aged , Age of Onset
11.
Neurosurg Rev ; 45(5): 3259-3269, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36056977

ABSTRACT

Endovascular coiling (EC) has been identified in systematic reviews and meta-analyses to produce more favourable clinical outcomes in comparison to neurosurgical clipping (NC) when surgically treating a subarachnoid haemorrhage from a ruptured aneurysm. Cost-effectiveness analyses between both interventions have been done, but no cost-utility analysis has yet been published. This systematic review aims to perform an economic analysis of the relative utility outcomes and costs from both treatments in the UK. A cost-utility analysis was performed from the perspective of the National Health Service (NHS), over a 1-year analytic horizon. Outcomes were obtained from the randomised International Subarachnoid Aneurysm Trial (ISAT) and measured in terms of the patient's modified Rankin scale (mRS) grade, a 6-point disability scale that aims to quantify a patient's functional outcome following a stroke. The mRS score was weighted against the Euro-QoL 5-dimension (EQ-5D), with each state assigned a weighted utility value which was then converted into quality-adjusted life years (QALYs). A sensitivity analysis using different utility dimensions was performed to identify any variation in incremental cost-effectiveness ratio (ICER) if different input variables were used. Costs were measured in pounds sterling (£) and discounted by 3.5% to 2020/2021 prices. The cost-utility analysis showed an ICER of - £144,004 incurred for every QALY gained when EC was utilised over NC. At NICE's upper willingness-to-pay (WTP) threshold of £30,000, EC offered a monetary net benefit (MNB) of £7934.63 and health net benefit (HNB) of 0.264 higher than NC. At NICE's lower WTP threshold of £20,000, EC offered an MNB of £7478.63 and HNB of 0.374 higher than NC. EC was found to be more 'cost-effective' than NC, with an ICER in the bottom right quadrant of the cost-effectiveness plane-indicating that it offers greater benefits at lower costs. This is supported by the ICER being below the NICE's threshold of £20,000-£30,000 per QALY, and both MNB and HNB having positive values (> 0).


Subject(s)
Subarachnoid Hemorrhage , Cost-Benefit Analysis , Humans , Quality of Life , State Medicine , Subarachnoid Hemorrhage/surgery
12.
Cell Rep Methods ; 2(9): 100280, 2022 09 19.
Article in English | MEDLINE | ID: mdl-36160044

ABSTRACT

In this study, we report static and perfused models of human myocardial-microvascular interaction. In static culture, we observe distinct regulation of electrophysiology of human induced pluripotent stem cell derived-cardiomyocytes (hiPSC-CMs) in co-culture with human cardiac microvascular endothelial cells (hCMVECs) and human left ventricular fibroblasts (hLVFBs), including modification of beating rate, action potential, calcium handling, and pro-arrhythmic substrate. Within a heart-on-a-chip model, we subject this three-dimensional (3D) co-culture to microfluidic perfusion and vasculogenic growth factors to induce spontaneous assembly of perfusable myocardial microvasculature. Live imaging of red blood cells within myocardial microvasculature reveals pulsatile flow generated by beating hiPSC-CMs. This study therefore demonstrates a functionally vascularized in vitro model of human myocardium with widespread potential applications in basic and translational research.


Subject(s)
Endothelial Cells , Induced Pluripotent Stem Cells , Humans , Myocardium , Myocytes, Cardiac , Coculture Techniques
13.
Int J Mol Sci ; 23(18)2022 Sep 19.
Article in English | MEDLINE | ID: mdl-36142853

ABSTRACT

Engagement of the sarcoplasmic reticulum (SR) Ca2+ stores for excitation-contraction (EC)-coupling is a fundamental feature of cardiac muscle cells. Extracellular matrix (ECM) proteins that form the extracellular scaffolding supporting cardiac contractile activity are thought to play an integral role in the modulation of EC-coupling. At baseline, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) show poor utilisation of SR Ca2+ stores, leading to inefficient EC-coupling, like developing or human CMs in cardiac diseases such as heart failure. We hypothesised that integrin ligand-receptor interactions between ECM proteins and CMs recruit the SR to Ca2+ cycling during EC-coupling. hiPSC-CM monolayers were cultured on fibronectin-coated glass before 24 h treatment with fibril-forming peptides containing the integrin-binding tripeptide sequence arginine-glycine-aspartic acid (2 mM). Micropipette application of 40 mM caffeine in standard or Na+/Ca2+-free Tyrode's solutions was used to assess the Ca2+ removal mechanisms. Microelectrode recordings were conducted to analyse action potentials in current-clamp. Confocal images of labelled hiPSC-CMs were analysed to investigate hiPSC-CM morphology and ultrastructural arrangements in Ca2+ release units. This study demonstrates that peptides containing the integrin-binding sequence arginine-glycine-aspartic acid (1) abbreviate hiPSC-CM Ca2+ transient and action potential duration, (2) increase co-localisation between L-type Ca2+ channels and ryanodine receptors involved in EC-coupling, and (3) increase the rate of SR-mediated Ca2+ cycling. We conclude that integrin-binding peptides induce recruitment of the SR for Ca2+ cycling in EC-coupling through functional and structural improvements and demonstrate the importance of the ECM in modulating cardiomyocyte function in physiology.


Subject(s)
Induced Pluripotent Stem Cells , Sarcoplasmic Reticulum , Arginine/metabolism , Aspartic Acid/metabolism , Caffeine/pharmacology , Calcium/metabolism , Fibronectins/metabolism , Glycine/metabolism , Humans , Integrins/metabolism , Ligands , Myocytes, Cardiac/metabolism , Ryanodine Receptor Calcium Release Channel/metabolism , Sarcoplasmic Reticulum/metabolism
14.
Int J Cardiol ; 367: 81-89, 2022 11 15.
Article in English | MEDLINE | ID: mdl-35944765

ABSTRACT

Sacubitril/valsartan is a first-in-class Angiotensin Receptor-Neprilysin inhibitor (ARNi) to be approved for the treatment of heart failure with reduced ejection fraction (HFrEF). The combination tablet has become a mainstay of treatment in the management of heart failure (HF) due to its composite inhibition of the neurohumoral system. There is growing support to show that sacubitril/valsartan may enhance glycaemic control through the augmentation of neprilysin substrates - in particular, glucagon-like peptide 1 (GLP-1). Given that HF and Diabetes Mellitus (DM) frequently coexist, with 44% of patients hospitalised with heart failure also having diabetes as a co-morbidity, it is plausible that sacubitril/valsartan may represent a novel way to address glucose intolerance in HF. However, the role of neprilysin in the degradation of GLP-1 raises important clinical considerations such as the risk of hypoglycaemia and potential drug-drug interactions in patients with and without concurrent DM. We review the current body of research addressing the effect of neprilysin inhibition on GLP-1 receptor signalling and discuss the implications for treatment of HF and DM.


Subject(s)
Heart Failure , Neprilysin , Aminobutyrates , Angiotensin Receptor Antagonists/pharmacology , Angiotensin Receptor Antagonists/therapeutic use , Biphenyl Compounds/pharmacology , Drug Combinations , Glucagon-Like Peptide 1/therapeutic use , Glucagon-Like Peptide-1 Receptor , Glycemic Control , Heart Failure/drug therapy , Humans , Receptors, Angiotensin , Stroke Volume , Tetrazoles/pharmacology , Valsartan/therapeutic use
15.
J Alzheimers Dis ; 88(4): 1567-1584, 2022.
Article in English | MEDLINE | ID: mdl-35811521

ABSTRACT

BACKGROUND: There is an urgent need for noninvasive, cost-effective biomarkers for Alzheimer's disease (AD), such as blood-based biomarkers. They will not only support the clinical diagnosis of dementia but also allow for timely pharmacological and nonpharmacological interventions and evaluations. OBJECTIVE: To identify and validate a novel blood-based microRNA biomarker for dementia of the Alzheimer's type (DAT). METHODS: We conducted microRNA sequencing using peripheral blood mononuclear cells isolated from a discovery cohort and validated the identified miRNAs in an independent cohort and AD postmortem tissues. miRNA correlations with AD pathology and AD clinical-radiological imaging were conducted. We also performed bioinformatics and cell-based assay to identify miRNA target genes. RESULTS: We found that miR-150-5p expression was significantly upregulated in DAT compared to mild cognitive impairment and healthy subjects. Upregulation of miR-150-5p was observed in AD hippocampus. We further found that higher miR-150-5p levels were correlated with the clinical measures of DAT, including lower global cognitive scores, lower CSF Aß42, and higher CSF total tau. Interestingly, we observed that higher miR-150-5p levels were associated with MRI brain volumes within the default mode and executive control networks, two key networks implicated in AD. Furthermore, pathway analysis identified the targets of miR-150-5p to be enriched in the Wnt signaling pathway, including programmed cell death 4 (PDCD4). We found that PDCD4 was downregulated in DAT blood and was downregulated by miR-150-5p at both the transcriptional and protein levelsConclusion:Our findings demonstrated that miR-150-5p is a promising clinical blood-based biomarker for DAT.


Subject(s)
Alzheimer Disease , MicroRNAs , Alzheimer Disease/blood , Alzheimer Disease/genetics , Amyloid beta-Peptides/metabolism , Apoptosis Regulatory Proteins/metabolism , Atrophy/pathology , Biomarkers/blood , Cognition , Humans , Leukocytes, Mononuclear/metabolism , MicroRNAs/metabolism , RNA-Binding Proteins
16.
Viruses ; 14(6)2022 06 17.
Article in English | MEDLINE | ID: mdl-35746793

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has resulted in over 6 million deaths and significant morbidity across the globe. Alongside common respiratory symptoms, COVID-19 is associated with a variety of cardiovascular complications in the acute and post-acute phases of infection. The suggested pathophysiological mechanisms that underlie these complications include direct viral infection of the myocardium via the angiotensin-converting enzyme 2 (ACE2) protein and a cytokine release syndrome that results in indirect inflammatory damage to the heart. Patients with pre-existing cardiovascular disease and co-morbidities are generally more susceptible to the cardiac manifestations of COVID-19. However, studies have identified a variety of complications in low-risk individuals, including young adults and children. Myocarditis and paediatric inflammatory multisystem syndrome temporally associated with COVID-19 (PIMS) are among the adverse events reported in the acute phase of infection. Furthermore, patients have reported cardiac symptoms persisting beyond the acute phase in post-COVID syndrome. This review summarises the acute and chronic cardiac consequences of COVID-19 in low-risk patients, explores the pathophysiology behind them, and discusses new predictive factors for poor outcomes.


Subject(s)
COVID-19 , Heart Diseases , COVID-19/complications , Child , Heart Diseases/etiology , Humans , Pandemics , SARS-CoV-2 , Systemic Inflammatory Response Syndrome
17.
ACS Chem Biol ; 17(6): 1440-1449, 2022 06 17.
Article in English | MEDLINE | ID: mdl-35587148

ABSTRACT

Covalent inhibitors are viable therapeutics. However, off-target reactivity challenges the field. Chemists have attempted to solve this issue by varying the reactivity attributes of electrophilic warheads. Here, we report the development of an approach to increase the selectivity of covalent molecules that is independent of warhead reactivity features and can be used in concert with existing methods. Using the scaffold of the Bruton's tyrosine kinase (BTK) inhibitor Ibrutinib for our proof-of-concept, we reasoned that increasing the steric bulk of fumarate-based electrophiles on Ibrutinib should improve selectivity via the steric exclusion of off-targets but retain rates of cysteine reactivity comparable to that of an acrylamide. Using chemical proteomic techniques, we demonstrate that elaboration of the electrophile to a tert-butyl (t-Bu) fumarate ester decreases time-dependent off-target reactivity and abolishes time-independent off-target reactivity. While an alkyne-bearing probe analogue of Ibrutinib has 247 protein targets, our t-Bu fumarate probe analogue has only 7. Of these 7 targets, BTK is the only time-independent target. The t-Bu inhibitor itself is also more selective for BTK, reducing off-targets by 70%. We investigated the consequences of treatment with Ibrutinib and our t-Bu analogue and discovered that only 8 proteins are downregulated in response to treatment with the t-Bu analogue compared to 107 with Ibrutinib. Of these 8 proteins, 7 are also downregulated by Ibrutinib and a majority of these targets are associated with BTK biology. Taken together, these findings reveal an opportunity to increase cysteine-reactive covalent inhibitor selectivity through electrophilic structure optimization.


Subject(s)
Protein Kinase Inhibitors , Proteomics , Agammaglobulinaemia Tyrosine Kinase/metabolism , Cysteine , Fumarates , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology
18.
J Alzheimers Dis ; 87(3): 1103-1114, 2022.
Article in English | MEDLINE | ID: mdl-35431245

ABSTRACT

BACKGROUND: White matter hyperintensities (WMH) are a known risk factor for cognitive decline. While the ɛ4 allele of apolipoprotein E gene (APOE4) is another risk factor for cognitive decline, it remains unclear how APOE4 affects the relationship between WMH and cognitive decline, specifically in the prodromal stage of dementia. OBJECTIVE: To determine how APOE4 moderates the relationship between WMH and cognition in prodromal dementia. METHODS: Two-hundred-sixteen participants with prodromal dementia underwent magnetic resonance imaging (MRI), neuropsychological testing (global and domain wise), cardiovascular risk factor assessments, and APOE genotyping. Visual ratings for WMH as well as total and lobar WMH volumes were quantified. Moderation analysis was performed to determine the influence of APOE4 on the relationship between WMH and performance on global and domain-specific cognitive measures. The role of confluent and non-confluent WMH on cognition was additionally studied using logistic regression. RESULTS: APOE4 carriers (n = 49) had poorer memory and higher global WMH (10.01 mL versus 6.23 mL, p = 0.04), temporal WMH (1.17 mL versus 0.58 mL, p = 0.01), and occipital WMH (0.38mL versus 0.22 mL, p = 0.02) compared to APOE4 non-carriers (n = 167). Moderation analysis revealed that APOE4 positivity strengthened the relationship between higher global as well as lobar WMH burden and poorer episodic memory. Furthermore, APOE4 carriers with confluent WMH were 4.81 times more likely to have impaired episodic memory compared to non-confluent WMH and non-APOE carriers. CONCLUSION: The impact of WMH on memory may be strongest among APOE4 carriers. Clinicians targeting WMH would need to consider the APOE4 allele and WMH severity status to strategize cognitive interventions.


Subject(s)
Apolipoprotein E4 , Cognitive Dysfunction , Leukoaraiosis , Memory Disorders , Memory, Episodic , White Matter , Apolipoprotein E4/genetics , Brain/pathology , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/genetics , Cognitive Dysfunction/pathology , Dementia/diagnostic imaging , Dementia/genetics , Dementia/pathology , Humans , Leukoaraiosis/diagnostic imaging , Leukoaraiosis/genetics , Leukoaraiosis/pathology , Magnetic Resonance Imaging , Memory Disorders/diagnostic imaging , Memory Disorders/genetics , Memory Disorders/pathology , Neuropsychological Tests , White Matter/diagnostic imaging , White Matter/pathology
19.
Clin Hypertens ; 28(1): 11, 2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35422052

ABSTRACT

BACKGROUND: Catheter-based renal denervation has been studied as a potential therapeutic option to reduce high blood pressure (BP). Preclinical studies in some experimental models have demonstrated an antihypertensive effect of renal denervation but reports from clinical trials have been mixed METHODS: We performed a literature search using combinations of the key terms 'Cardiovascular diseases, Clinical trial, Pre-clinical trials, Resistant hypertension, Renal denervation, Ablation technique, Radiofrequency ablation, Ultrasound ablation, RADIANCE SOLO, SYMPLICITY HTN, SYPRAL HTN'. The databases searched were PubMed and OVID Medline. RESULTS: The initial SYMPLICITY HTN-1 AND HTN-2 clinical trials reported significant decreases in office BP but results from the more robustly designed SYMPLICITY HTN-3 trial, which included sham controls and ambulatory BP monitoring, showed no significant antihypertensive effect. Interest in the use of renal denervation in hypertension was once again sparked by favourable results from the SPYRAL HTN-OFF Med trial CONCLUSION: We provide a thorough, critical analysis of key preclinical and clinical studies investigating the efficacy of catheter-based renal denervation as a treatment for hypertension and highlight future areas for research to allow better translation into clinical practice.

20.
Cells ; 11(7)2022 03 30.
Article in English | MEDLINE | ID: mdl-35406735

ABSTRACT

Cardiac fibroblasts regulate the development of the adult cardiomyocyte phenotype and cardiac remodeling in disease. We investigate the role that cardiac fibroblasts-secreted extracellular vesicles (EVs) have in the modulation of cardiomyocyte Ca2+ cycling-a fundamental mechanism in cardiomyocyte function universally altered during disease. EVs collected from cultured human cardiac ventricular fibroblasts were purified by centrifugation, ultrafiltration and size-exclusion chromatography. The presence of EVs and EV markers were identified by dot blot analysis and electron microscopy. Fibroblast-conditioned media contains liposomal particles with a characteristic EV phenotype. EV markers CD9, CD63 and CD81 were highly expressed in chromatography fractions that elute earlier (Fractions 1-15), with most soluble contaminating proteins in the later fractions collected (Fractions 16-30). Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were treated with fibroblast-secreted EVs and intracellular Ca2+ transients were analyzed. Fibroblast-secreted EVs abbreviate the Ca2+ transient time to peak and time to 50% decay versus serum-free controls. Thus, EVs from human cardiac fibroblasts represent a novel mediator of human fibroblast-cardiomyocyte interaction, increasing the efficiency of hiPSC-CM Ca2+ handling.


Subject(s)
Extracellular Vesicles , Induced Pluripotent Stem Cells , Calcium/metabolism , Extracellular Vesicles/metabolism , Fibroblasts , Humans , Induced Pluripotent Stem Cells/metabolism , Myocytes, Cardiac/metabolism
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