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1.
Sensors (Basel) ; 24(8)2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38676111

ABSTRACT

This paper introduces an innovative approach to 3D environmental mapping through the integration of a compact, handheld sensor package with a two-stage sensor fusion pipeline. The sensor package, incorporating LiDAR, IMU, RGB, and thermal cameras, enables comprehensive and robust 3D mapping of various environments. By leveraging Simultaneous Localization and Mapping (SLAM) and thermal imaging, our solution offers good performance in conditions where global positioning is unavailable and in visually degraded environments. The sensor package runs a real-time LiDAR-Inertial SLAM algorithm, generating a dense point cloud map that accurately reconstructs the geometric features of the environment. Following the acquisition of that point cloud, we post-process these data by fusing them with images from the RGB and thermal cameras and produce a detailed, color-enriched 3D map that is useful and adaptable to different mission requirements. We demonstrated our system in a variety of scenarios, from indoor to outdoor conditions, and the results showcased the effectiveness and applicability of our sensor package and fusion pipeline. This system can be applied in a wide range of applications, ranging from autonomous navigation to smart agriculture, and has the potential to make a substantial benefit across diverse fields.

2.
Hepatol Commun ; 8(4)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38563583

ABSTRACT

BACKGROUND: Brief alcohol interventions use patient-provider communication to promote alcohol cessation. We characterized the receipt of this intervention in chronic liver disease (CLD). METHODS: We surveyed patients with CLD for weekly drinking patterns and examined associations with patient-provider communication receipt. RESULTS: Among 840 participants, 82.1% and 56.5% reported ≥1 standard drink weekly and excessive alcohol consumption, respectively. Patient-provider communication was lower in noncirrhotic (adjusted odds ratio:0.34, 95% CI: 0.22-0.54) and nonalcohol-associated CLD (adjusted odds ratio: 0.22, 95% CI: 0.15-0.34) among individuals drinking ≥1 standard drink weekly, and similarly in noncirrhotic CLD (adjusted odds ratio: 0.45, 95% CI: 0.21-0.95) among those with excessive drinking. CONCLUSIONS: Brief alcohol interventions are underutilized in noncirrhotic and nonalcohol-associated CLD.


Subject(s)
Alcohol Drinking , Liver Diseases , Humans , Alcohol Drinking/epidemiology , Health Behavior , Surveys and Questionnaires
3.
Hepatol Commun ; 8(4)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38497931

ABSTRACT

BACKGROUND: Alcohol-associated liver disease (ALD), encompassing alcohol-associated hepatitis and alcohol-associated cirrhosis, is rising in the United States. Racial and ethnic disparities are evident within ALD; however, the precise nature of these disparities is poorly defined. METHODS: We conducted a search of the PubMed/MEDLINE and EMBASE databases to identify studies published from inception through September 2023 that reported ALD incidence, prevalence, and mortality within the United States, stratified by race and ethnicity. We calculated pooled prevalence and incidence by race and ethnicity, including risk ratios and ORs for ALD pooled prevalence and alcohol-associated hepatitis/alcohol-associated cirrhosis pooled proportions, and OR for ALD mortality using the DerSimonian and Laird method for random-effect models. RESULTS: We identified 25 relevant studies (16 for quantitative meta-analysis), comprising 76,867,544 patients. ALD prevalence was highest in Hispanic (4.5%), followed by White (3.1%) and Black (1.4%) individuals. Pooled risk ratios of ALD prevalence were 1.64 (95% CI: 1.12-2.39) for Hispanic and 0.59 (95% CI: 0.35-0.87) for Black compared to White individuals. Mortality among those with ALD did not significantly differ between White and Hispanic (OR: 1.54, 95% CI: 0.9-2.5; I2=0%), Black (OR: 1.2, 95% CI: 0.8-1.6; I2=0%), or Native American (OR: 2.41, 95% CI: 0.9-2.9) individuals, while there was a significant difference between White and Asian (OR: 0.1; 95% CI: 0.03-0.5) individuals. Most data were cross-sectional and assessed to be of poor or fair quality. CONCLUSIONS: Differences were observed in ALD epidemiology, including higher prevalence among Hispanic and lower prevalence among Black individuals, although there were smaller differences in ALD mortality. Differences in ALD prevalence and prognosis remain poorly defined based on existing data, highlighting a need for higher-quality epidemiological studies in this area.


Subject(s)
Hepatitis, Alcoholic , Liver Diseases, Alcoholic , Humans , Ethnicity , Liver Cirrhosis , Liver Cirrhosis, Alcoholic , Liver Diseases, Alcoholic/epidemiology , United States/epidemiology , Racial Groups , Health Status Disparities
4.
Clin Neurophysiol Pract ; 9: 106-111, 2024.
Article in English | MEDLINE | ID: mdl-38516616

ABSTRACT

Objective: Epilepsy patients with mesial temporal sclerosis (MTS) on imaging who are drug-resistant usually undergo epilepsy surgery without previous invasive evaluation. However, up to one-third of patients are not seizure-free after surgery. Prior studies have identified risk factors for surgical failure, but it is unclear if they are associated with bilateral or discordant seizure onset. Methods: In this retrospective case series, we identified 17 epilepsy patients who had MRI-confirmed MTS but received invasive stereo-EEG (SEEG) evaluation before definitive intervention. We analyzed their presurgical risk factors in relation to SEEG seizure onset localization and MRI/SEEG concordance. Results: SEEG ictal onset was concordant with MTS localization (i.e. seizures started only from the hippocampus with MTS) in 5 out of 13 patients with unilateral MTS (UMTS) and in 3 out of 4 patients with bilateral MTS.No statistically significant association regarding concordance of SEEG ictal onset and MTS location was found in patients with such risk factors as a history of non-mesial temporal aura, frequent focal to bilateral tonic-clonic seizures, prior viral brain infection, or family history of epilepsy. Nine out of 13 UMTS patients had resective surgery only, 5 out of 9 (56 %) have Engel class I outcome at most recent follow-up (median 46.5 months, range 22-91 months). In Engel class I cohort, the SEEG ictal onset was concordant with MTS location in 3 out of 5 patients, and 2 patients had ipsilateral temporal neocortical ictal onset. Conclusions: Our findings suggest that patients with MTS might have discordant SEEG ictal onset (in 61.5% patients with UMTS in presented cohort), which may explain poor surgical outcome after destructive surgery in these cases. Significance: Although no statistically significant association was found in this under-powered study, these findings could be potentially valuable for future meta-analyses.

5.
Transplantation ; 108(2): e22, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38254284
6.
Neural Netw ; 144: 639-647, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34656050

ABSTRACT

Recurrent neural networks can solve a variety of computational tasks and produce patterns of activity that capture key properties of brain circuits. However, learning rules designed to train these models are time-consuming and prone to inaccuracies when tuning connection weights located deep within the network. Here, we describe a rapid one-shot learning rule to train recurrent networks composed of biologically-grounded neurons. First, inputs to the model are compressed onto a smaller number of recurrent neurons. Then, a non-iterative rule adjusts the output weights of these neurons based on a target signal. The model learned to reproduce natural images, sequential patterns, as well as a high-resolution movie scene. Together, results provide a novel avenue for one-shot learning in biologically realistic recurrent networks and open a path to solving complex tasks by merging brain-inspired models with rapid optimization rules.


Subject(s)
Neural Networks, Computer , Neurons , Action Potentials , Learning , Models, Neurological
7.
JAMA Netw Open ; 2(5): e193290, 2019 05 03.
Article in English | MEDLINE | ID: mdl-31050779

ABSTRACT

Importance: The measured severity of illness of hospitalized Medicare beneficiaries has increased. Whether this change is associated with payment reforms, concentrated among hospitalizations with principal diagnoses targeted by payment reform, and reflective of true increases in severity of illness is unknown. Objectives: To assess whether the expansion of secondary diagnosis codes in January 2011 and the incentive payments for health information technology under the US Health Information Technology for Economic and Clinical Health Act were associated with changes in measured severity of illness and whether those changes are reflective of true increases in underlying patient severity. Design, Setting, and Participants: This cohort study of Medicare fee-for-service beneficiary discharges (N = 47 951 443) between January 1, 2008, and August 31, 2015, used a regression-discontinuity design to evaluate changes in measured severity of illness after the expansion of secondary diagnoses. Discharge-level linear regression model with hospital fixed effects was used to evaluate changes in measured severity of illness after hospitals' receipt of incentives for health information technology. The change in predictive accuracy of measured severity of illness on 30-day readmissions after the implementation of both policies was evaluated. Data analysis was performed from November 1, 2018, to March 5, 2019. Main Outcomes and Measures: The primary outcome was patients' measured severity of illness determined by the number of condition categories from secondary discharge diagnosis codes. Measured severity of illness for diagnoses commonly targeted by Medicare policies and untargeted diagnoses was assessed. Results: In total, 47 951 443 discharges at 2850 hospitals were included. In 2008, these beneficiaries included 3 882 672 women (58.5%) with a mean (SD) age of 78.5 (8.4) years. In 2014, the discharges included 3 377 137 women (57.8%) with the mean (SD) age of 78.4 (8.7) years. The Centers for Medicare & Medicaid Services expansion of secondary diagnoses was associated with a 0.348 (95% CI, 0.328-0.367; P < .001) change in condition categories for all diagnoses, 0.445 (95% CI, 0.419-0.470; P < .001) for targeted diagnoses, and 0.321 (95% CI, 0.302-0.341; P < .001) for untargeted diagnoses. Health information technology incentives were associated with a 0.013 (95% CI, 0.004-0.022; P = .005) change in condition categories for all diagnoses, 0.195 (95% CI, 0.184-0.207; P < .001) for targeted diagnoses, and -0.016 (95% CI, -0.025 to -0.007; P < .001) for untargeted diagnoses. Minimal improvements in predictive accuracy were observed. Conclusions and Relevance: Changes in Centers for Medicare & Medicaid Services policies appear to be associated with increases in measured severity of illness; these increases do not appear to reflect substantive changes in true patient severity.


Subject(s)
Fee-for-Service Plans/economics , Health Care Reform , Medicare/legislation & jurisprudence , Severity of Illness Index , Aged , Aged, 80 and over , Cohort Studies , Female , Hospitals/statistics & numerical data , Humans , Male , Medicare/economics , Medicare/statistics & numerical data , Patient Discharge/statistics & numerical data , United States/epidemiology
8.
J Mater Sci Mater Med ; 28(11): 172, 2017 Sep 27.
Article in English | MEDLINE | ID: mdl-28956202

ABSTRACT

Trilayered polypyrrole (PPy) actuators have high stress density, low modulus and have wide potential biological applications including use in artificial muscles and in limb prosthesis after limb amputation. This article examines the in vivo biocompatibility of actuators in muscle using rabbit models. The actuators were specially designed with pores to encourage tissue in growth; this study also assessed the effect of such pores on the stability of the actuators in vivo. Trilayered PPy actuators were either laser cut with 150 µm pores or left pore-less and implanted into rabbit muscle for 3 days, 2 weeks, 4 weeks and 8 weeks and retrieved subsequently for histological analysis. In a second set of experiments, the cut edges of pores in porous actuator strips were further sealed by PPy after laser cutting to further improve its stability in vivo. Porous actuators with and without PPy sealing of pore edges were implanted intramuscularly for 4 and 8 weeks and assessed with histology. Pore-less actuators incited a mild inflammatory response, becoming progressively walled off by a thin layer of fibrous tissue. Porous actuators showed increased PPy fragmentation and delamination with associated greater foreign body response compared to pore-less actuators. The PPy fragmentation was minimized when the pore edges were sealed off by PPy after laser cutting showing less PPy debris. Laser cutting of the actuators with pores destabilizes the PPy. This can be overcome by sealing the cut edges of the pores with PPy after laser. The findings in this article have implications in future design and manufacturing of PPy actuator for use in vivo.


Subject(s)
Artificial Limbs , Biocompatible Materials/chemistry , Coated Materials, Biocompatible/chemistry , Polymers/chemistry , Prostheses and Implants , Pyrroles/chemistry , Amputation, Surgical/rehabilitation , Animals , Coated Materials, Biocompatible/chemical synthesis , Coated Materials, Biocompatible/pharmacology , Materials Testing , Polymers/pharmacology , Porosity , Prosthesis Implantation , Pyrroles/pharmacology , Rabbits
9.
Dev Neurobiol ; 76(5): 551-65, 2016 May.
Article in English | MEDLINE | ID: mdl-26251299

ABSTRACT

Clustering of acetylcholine receptors (AChR) at the postsynaptic membrane is a crucial step in the development of neuromuscular junctions (NMJ). During development and after denervation, aneural AChR clusters form on the sarcolemma. Recent studies suggest that these receptors are critical for guiding and initiating synaptogenesis. The aim of this study is to investigate the effect of agrin and laminin-1; agents with known AChR clustering activity; on NMJ formation and muscle maturation. Primary myoblasts were differentiated in vitro on collagen, laminin or collagen and laminin-coated surfaces in the presence or absence of agrin and laminin. The pretreated cells were then subject to innervation by PC12 cells. The number of neuromuscular junctions was assessed by immunocytochemical co-localization of AChR clusters and the presynaptic marker synaptophysin. Functional neuromuscular junctions were quantitated by analysis of the level of spontaneous as well as neuromuscular blocker responsive contractile activity and muscle maturation was assessed by the degree of myotube striation. Agrin alone did not prime muscle for innervation while a combination of agrin and laminin pretreatment increased the number of neuromuscular junctions formed and enhanced acetylcholine based neurotransmission and myotube striation. This study has direct clinical relevance for treatment of denervation injuries and creating functional neuromuscular constructs for muscle tissue repair.


Subject(s)
Agrin/metabolism , Laminin/metabolism , Neuromuscular Junction/growth & development , Neuromuscular Junction/metabolism , Receptors, Cholinergic/metabolism , Agrin/administration & dosage , Animals , Cell Differentiation/physiology , Cells, Cultured , Coculture Techniques , Culture Media , Laminin/administration & dosage , Mice, Inbred C57BL , Muscle Contraction/physiology , Muscle Fibers, Skeletal/metabolism , Muscle Fibers, Skeletal/ultrastructure , Myoblasts/metabolism , Myoblasts/ultrastructure , Neuromuscular Junction/ultrastructure , PC12 Cells , Rats
10.
Int J Mol Sci ; 15(7): 11878-921, 2014 Jul 04.
Article in English | MEDLINE | ID: mdl-25000263

ABSTRACT

Joint replacement is a major orthopaedic procedure used to treat joint osteoarthritis. Aseptic loosening and infection are the two most significant causes of prosthetic implant failure. The ideal implant should be able to promote osteointegration, deter bacterial adhesion and minimize prosthetic infection. Recent developments in material science and cell biology have seen the development of new orthopaedic implant coatings to address these issues. Coatings consisting of bioceramics, extracellular matrix proteins, biological peptides or growth factors impart bioactivity and biocompatibility to the metallic surface of conventional orthopaedic prosthesis that promote bone ingrowth and differentiation of stem cells into osteoblasts leading to enhanced osteointegration of the implant. Furthermore, coatings such as silver, nitric oxide, antibiotics, antiseptics and antimicrobial peptides with anti-microbial properties have also been developed, which show promise in reducing bacterial adhesion and prosthetic infections. This review summarizes some of the recent developments in coatings for orthopaedic implants.


Subject(s)
Coated Materials, Biocompatible/chemistry , Joint Prosthesis , Animals , Ceramics/chemistry , Extracellular Matrix Proteins/chemistry , Humans
11.
Int J Artif Organs ; 37(4): 277-91, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24811182

ABSTRACT

Nerve injury secondary to trauma, neurological disease or tumor excision presents a challenge for surgical reconstruction. Current practice for nerve repair involves autologous nerve transplantation, which is associated with significant donor-site morbidity and other complications. Previously artificial nerve conduits made from polycaprolactone, polyglycolic acid and collagen were approved by the FDA (USA) for nerve repair. More recently, there have been significant advances in nerve conduit design that better address the requirements of nerve regrowth. Innovations in materials science, nanotechnology, and biology open the way for the synthesis of new generation nerve repair conduits that address issues currently faced in nerve repair and regeneration. This review discusses recent innovations in this area, including the use of nanotechnology to improve the design of nerve conduits and to enhance nerve regeneration.


Subject(s)
Guided Tissue Regeneration/methods , Nerve Regeneration , Nervous System Diseases/surgery , Regenerative Medicine/methods , Tissue Engineering/methods , Animals , Biocompatible Materials , Genetic Therapy , Humans , Nanomedicine , Nervous System Diseases/genetics , Nervous System Diseases/pathology , Nervous System Diseases/physiopathology , Stem Cell Transplantation , Tissue Scaffolds , Treatment Outcome
12.
J Biomed Opt ; 19(5): 056006, 2014 May.
Article in English | MEDLINE | ID: mdl-24817619

ABSTRACT

An acousto-optic tunable filter (AOTF)-based multispectral imaging microscope system allows the combination of cellular morphology and multiple biomarker stainings on a single microscope slide. We describe advances in AOTF technology that have greatly improved spectral purity, field uniformity, and image quality. A multispectral imaging bright field microscope using these advances demonstrates pathology results that have great potential for clinical use.


Subject(s)
Biomarkers, Tumor/analysis , Cytological Techniques/methods , Microscopy/methods , Photoacoustic Techniques/methods , Cytological Techniques/instrumentation , Female , Humans , Microscopy/instrumentation , Papanicolaou Test , Photoacoustic Techniques/instrumentation , Uterine Cervical Neoplasms
13.
PLoS Med ; 6(12): e1000194, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19997499

ABSTRACT

BACKGROUND: Data on absolute risks of outcomes and patterns of drug use in cost-effectiveness analyses are often based on randomised clinical trials (RCTs). The objective of this study was to evaluate the external validity of published cost-effectiveness studies by comparing the data used in these studies (typically based on RCTs) to observational data from actual clinical practice. Selective Cox-2 inhibitors (coxibs) were used as an example. METHODS AND FINDINGS: The UK General Practice Research Database (GPRD) was used to estimate the exposure characteristics and individual probabilities of upper gastrointestinal (GI) events during current exposure to nonsteroidal anti-inflammatory drugs (NSAIDs) or coxibs. A basic cost-effectiveness model was developed evaluating two alternative strategies: prescription of a conventional NSAID or coxib. Outcomes included upper GI events as recorded in GPRD and hospitalisation for upper GI events recorded in the national registry of hospitalisations (Hospital Episode Statistics) linked to GPRD. Prescription costs were based on the prescribed number of tables as recorded in GPRD and the 2006 cost data from the British National Formulary. The study population included over 1 million patients prescribed conventional NSAIDs or coxibs. Only a minority of patients used the drugs long-term and daily (34.5% of conventional NSAIDs and 44.2% of coxibs), whereas coxib RCTs required daily use for at least 6-9 months. The mean cost of preventing one upper GI event as recorded in GPRD was US$104k (ranging from US$64k with long-term daily use to US$182k with intermittent use) and US$298k for hospitalizations. The mean costs (for GPRD events) over calendar time were US$58k during 1990-1993 and US$174k during 2002-2005. Using RCT data rather than GPRD data for event probabilities, the mean cost was US$16k with the VIGOR RCT and US$20k with the CLASS RCT. CONCLUSIONS: The published cost-effectiveness analyses of coxibs lacked external validity, did not represent patients in actual clinical practice, and should not have been used to inform prescribing policies. External validity should be an explicit requirement for cost-effectiveness analyses.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/economics , Cyclooxygenase 2 Inhibitors/economics , Gastrointestinal Diseases/economics , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Cost-Benefit Analysis , Cyclooxygenase 2 Inhibitors/adverse effects , Cyclooxygenase 2 Inhibitors/therapeutic use , Gastrointestinal Diseases/prevention & control , Hospitalization/economics , Humans , Models, Theoretical , Prescriptions/economics , Probability , Randomized Controlled Trials as Topic , Treatment Outcome , United Kingdom
14.
J Hypertens ; 27(7): 1485-92, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19491706

ABSTRACT

AIM: To describe the patterns of risks of acute myocardial infarction (MI) during exposure to long-acting beta2-agonists (LABA). METHODS: The study population consisted of patients aged 18+ years prescribed LABA or short-acting beta2-agonists (SABA) in the UK General Practice Research Database (GPRD). The outcomes included acute MI as recorded in GPRD and hospitalization for acute MI as obtained from the national registry of hospital admissions in England. The patterns of the hazard rates over time (i.e. absolute risks) were evaluated. RESULTS: The study population included 507,966 patients, who received a total of 5.5 million inhaled SABA, 4.0 million inhaled corticosteroids (ICS) and 1.3 million LABA prescriptions. In patients who recently started asthma medication, there were substantial changes in the hazard rates of MI over time: hazard rates were increased shortly following the prescription and then decreased. The hazard rates of MI in GPRD and of MI hospitalizations were proportional over time between inhaled SABA, LABA and ICS. Heavy long-term users (13+ Rx of the same asthma drug in the 1 year before) had increased risks of MI both with inhaled SABA and ICS. The relative rate in the heavy long-term users was 1.6 with inhaled SABA, 1.1 with LABA and 1.7 with ICS. The pattern of risk was similar between LABA with and without concomitant ICS use. CONCLUSION: The patterns of risks of MI were broadly similar between inhaled SABA, LABA and ICS, suggesting that there were no major differences between these drugs.


Subject(s)
Adrenergic beta-Agonists/adverse effects , Anti-Asthmatic Agents/adverse effects , Database Management Systems , Myocardial Infarction/epidemiology , Administration, Inhalation , Adolescent , Adrenergic beta-Agonists/administration & dosage , Adult , Aged , Aged, 80 and over , Anti-Asthmatic Agents/administration & dosage , Female , Humans , Male , Middle Aged , Risk Factors , United Kingdom , Young Adult
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