Prediction of response to cardiac resynchronization therapy using cardiac magnetic resonance imaging in non-ischemic dilated cardiomyopathy

Background

Cardiac resynchronization therapy (CRT) is a well-established therapy for symptomatic heart failure with reduced ejection fraction, but the response is different for individuals. Although many modalities have been conducted to predict CRT response, cardiac magnetic resonance (CMR) to predict CRT response has still insufficient usefulness.

Purpose

We determine whether the parameters including late gadolinium enhancement (LGE) identified in CMR could act as predictors of CRT response.

Methods

We retrospectively investigated 124 patients with non-ischemic dilated cardiomyopathy who underwent CMR before CRT implantation between Jan 2010 and July 2021 in a single center. CRT response was defined as a decrease in left ventricular end-systolic volume (LVESV) >15% on echocardiography after at least 3 months after CRT implantation.

Results

Among the study population (mean age 65.7±11.2 years, mean EF 25±6.5%, 50% of female), 85 (69%) patients were defined as CRT responder. The CRT responders had more left bundle branch block (LBBB) compared with non-responders [79 (92.9%) vs. 23 (59.0%), p<0.001], but there was a no difference of QRS duration (158.7 vs 165.0ms, p=0.054) between two groups. CMR analysis showed that there were no significant differences in the left ventricular (LV) chamber volume and LV ejection fraction between CRT-responder and non-responder. However, the right ventricular (RV) chamber volume was smaller (RV end-diastolic volume index, 86.3 vs 103.5 ml/m2, p=0.039; RV end-systolic volume index, 49.3 vs 68.5 ml/m2, p=0.013) and the RV ejection fraction (RVEF) was higher (46.9 vs 37.6%, p=0.002) in CRT-responders compared with non-responders. The LGE on CMR was more shown in non-responders than in CRT-responders [33 (84.6%) vs 45 (52.9%), p<0.001]. In CMR parameters, RV dysfunction (RVEF <45%) [Odds ratio (OR), 0.21 (0.05–0.93), p=0.045] and LGE [OR, 0.21 (0.05–0.58), p=0.01] were significantly associated with poor CRT response.

Conclusions

The presence of LGE and RV dysfunction on CMR were associated with poor CRT response in patients with non-ischemic dilated cardiomyopathy. Further investigation with CMR for pre-CRT patients is needed to support these results.

Funding Acknowledgement

Type of funding sources: None.

Genetic analysis of Korean non-ischemic dilated cardiomyopathy using next generation sequencing

Background

Non-ischemic dilated cardiomyopathy (NIDCM) is a genetic disorder that causes heart failure and life-threatening arrhythmia. However, there has been no study about the up-to-date genetic analysis for NIDCM in Korean. Therefore, we performed the genetic analysis of Korean NIDCM patients (pts) using next generation sequencing (NGS).

Methods

We analyzed clinical and echocardiographic data of 203 NIDCM in a single center from July 2017 to May 2020. All pts underwent NGS analysis with customized panel including 369 genes. Genetic variants were classified as pathogenic, likely pathogenic mutations or variants of uncertain significance regarding American College of Medical Genetics guideline.

Results

A total of 203 NIDCM pts (57±15 years old, 32.0% male, LVEF 28%) had NGS analysis. Thirty-seven (18.2%) pts had pathogenic or likely pathogenic mutations. The most prevalent mutated genes were TTN (n=16, 43.2%). TNNT2 (n=6, 16.2%), MYBPC3 (n=6, 16.2%) and MYH7 (n=3, 8.1%) mutated genes were common in the following order. The patients with positive panel mutation had no significant difference in initial LVEF (27% vs. 28%, p=0.216) and prevalence of atrial fibrillation (37.8% vs. 44.6%, p=0.454) compared with patients with negative panel mutation. During the median follow-up period of 40 months, there was no significant difference in composite outcome (all-cause death, heart transplantation, LVAD, heart failure re-admission, fatal arrhythmia) (35.3% vs. 32.2%, p=0.729) or presence of improved EF (≥10 points increase from baseline LVEF, and a second measurement of LVEF >40%) (41.2% vs. 50.0%, p=0.354) between the two groups.

Conclusion

This is the first study of NGS analysis in Korean NIDCM pts. We could find disease-related pathogenic or likely pathogenic mutations in 18.2% NIDCM patients. Further prospective, large study should be warranted to elucidate the effect of genetic mutation in clinical manifestation and prognosis of NIDCM in Korean population.

Funding Acknowledgement

Type of funding sources: None.

In-hospital glycemic variability and all-cause mortality in patients hospitalized with acute heart failure: analysis of the KorAHF registry

Introduction

Glycemic variability (GV) is known to be a poor prognostic marker in various diseases including cardiovascular disease.

Purpose

We investigated the association of GV with all-cause mortality in patients with acute heart failure (HF).

Methods

The Korean Acute Heart Failure registry enrolled patients hospitalized for acute HF from 2011 to 2014. Among survivors of the index hospitalization, we analyzed those who had ≥3 blood glucose measurements before discharge. Patients were divided into two groups based on their coefficient of variation (%CV) as an indicator of GV. We investigated all-cause mortality at 6 month and 1 year after discharge.

Results

The study analyzed 2,617 patients (median age 72 years, 53% male). During the median follow-up period of 11 months, 583 (22%) patients died. Compared to alive patients, patients who died had a significantly higher diabetes prevalence (46% vs. 41%, P=0.035) and higher %CV (31.0% vs. 27.5%, P<0.001). Kaplan-Meier curve analysis revealed that a high GV (%CV >21%) was associated with lower cumulative survival to all-cause death compared with a low GV (%CV ≤21%) (log-rank P<0.001). Multivariate Cox proportional analysis showed that a high GV was associated with an increased risk of 6-month mortality (hazard ratio [HR] 2.02, 95% CI 1.58–2.59, P<0.001) and one-year mortality (HR 1.57, 95% CI 1.29–1.91, P<0.001). The risk of high GV for one-year mortality was significant in non-diabetic patients (HR 1.98, 95% CI 1.55–2.53, P<0.001), but not in diabetic patients (HR 1.24, 95% CI 0.91–1.69, P=0.176; P-for-interaction=0.030).

Conclusion

A high GV (%CV >21%) before discharge was associated with all-cause mortality within 1 year, especially in non-diabetic acute HF patients.

Funding Acknowledgement

Type of funding sources: None.

Impact of proportionate versus disproportionate mitral regurgitation on acute procedural changes and clinical outcomes following transcatheter mitral valve repair

Background

Transcatheter mitral edge-to-edge repair (TEER) with MitraClip offers a less invasive alternative for patients with severe, symptomatic mitral regurgitation (MR) who are considered high risk for surgery. However, patient selection for TEER remains challenging given the variability in underlying MR pathology and current discordance among studies regarding predictors of procedural efficacy and clinical outcomes.

Purpose

This study aimed to assess acute procedural changes and long-term outcomes in patients who underwent TEER according to the proportionality of MR, defined as the ratio of the effective regurgitant orifice area (EROA) and left ventricular end-diastolic volume (LVEDV).

Methods

We analyzed patients who underwent TEER at our institution between 2014 and 2020 with available biplane left ventricular volume measurement. Relevant clinical comorbidities, demographics, and anthropometrics, along with pertinent pre- and post-procedural echocardiogram measurements, were obtained by review of the electronic medical record. The EROA to LVEDV index was calculated for all patients who were then stratified by quartiles. Patients with an EROA/LVEDV index in the lowest quartile were defined as having the most proportionate MR and those with an index in the highest quartile were defined as the most disproportionate MR. Baseline and post-TEER parameters were used to assess acute procedural and longitudinal outcomes.

Results

Baseline clinical and echocardiographic parameters of the 230 subjects according to quartile are shown in the table. Following TEER, there was a larger reduction in the left ventricular end-diastolic diameter and increased MR reduction with increasingly disproportionate MR (p=0.03 and p=0.05, respectively). The change in ejection fraction pre- versus post-TEER did not significantly differ across groups (p=0.64). Median follow up time was 1.7 (0.7–3.5) years; mortality occurred in 77 patients (33.5%) and heart failure hospitalizations occurred in 20 patients (8.7%) during follow up. No significant difference in all-cause mortality or post-procedural heart failure hospitalizations was identified across groups.

Conclusions

In our series, patients with proportionate MR were similarly symptomatic to those with disproportionate MR but had less severe MR with increased comorbidities. Post-TEER MR grade was similar between groups. Longer-term follow up in larger groups of patients is needed to determine the clinical implications.

Funding Acknowledgement

Type of funding sources: None.

The association between frailty and physical performance in elderly patients with heart failure

Background

Frailty is known to be an important prognostic indicator in heart failure (HF). The Korean version of the frail scale for Koreans (K-FRAIL) has been developed and verified. The purpose of this study is to analyze the relationship between the K-FRAIL scale and physical performance, including muscular fitness and aerobic capacity in patients with HF.

Methods

This study included 143 HF patients aged over 65 years from a single tertiary hospital. In these subjects, muscular fitness was assessed using the handgrip test and knee extensor strength measurement, and aerobic capacity was assessed by cardiopulmonary exercise test and 6-minute walk test. Frailty status was measured using the K-FRAIL questionnaire and was classified as robust (K-FRAIL scale: 0), prefrail (1–2), and frail (3–5).

Results

Mean age of participants with robust (N=37), prefrail (N=75), and frail (N=31) were 72.5, 73.5, and 76.3 years, respectively. There was no difference in sex and left ventricular ejection fraction (LVEF) among groups, but the estimated glomerular filtration rate (eGFR) was significantly lower as frailty status increased (75.6±17.2 vs. 70.0±20.5 vs. 56.1±23.7 mL/min/1.73 m2; P<0.001). Hand-grip strength and knee extensor muscle strength did not differ among groups. However, peak oxygen consumption (peak VO2; 22.8±5.0 vs. 19.3±4.6 vs. 16.9±4.7 mL/kg/min, P<0.001) and 6-min walk distance (458.4±68.2 vs. 404.5±92.3 vs. 311.2±120.5 m; p<0.001) significantly decreased according to frailty severity. In multivariate regression analysis adjusted for age, sex, haemoglobin, eGFR and LVEF, peak VO2 (β=−0.311; P=0.002) and 6-min walk distance (β=−0.384; P<0.001) showed a significant inverse association with the K-FRAIL scale. With the cut-off value from receiver-operating characteristic curve analysis, peak VO2 (hazard ratio, 5.08; p=0.023) and 6MWT (hazard ratio, 3.99; p=0.020) were independent predictor of frailty according to K-FRAIL scale.

Conclusion

In elderly HF patients, physical performance differs according to frailty status, peak VO2 and 6-min walk distance correlates with the K-FRAIL scale better than muscular fitness.

Funding Acknowledgement

Type of funding sources: None.

4 year outcomes in a prospective evaluation of transcatheter mitral valve-in-valve, valve-in-ring and valve-in-mitral annular calcification: results from the MITRAL trial

Background

The MITRAL Trial (Mitral Implantation of TRAnscatheter vaLves) evaluates the safety and feasibility of balloon-expandable aortic transcatheter heart valves in patients with severe mitral valve disease with mitral annular calcification (MAC), failed surgical rings or failed bioprostheses.

Purpose

We sought to evaluate 4-year outcomes of patients enrolled in the MITRAL trial.

Methods

This is a prospective study that enrolled 91 high surgical risk patients at 13 sites in the U.S. 30 patients underwent Mitral Valve-in-Valve (MViV), 30 Valve-in-Ring (MViR) and 31 Valve-in-MAC (ViMAC). 4-year outcomes of these patients were evaluated in this analysis. Primary endpoints and key serious adverse events including deaths were adjudicated by an independent Clinical Events Committee. Cardiac computed tomography (CT) and echocardiographic images were evaluated by independent CT and Echocardiographic Core Laboratories.

Results

Mean age was 74.3±8.9 years. Most patients undergoing MViV and ViMAC were female (MVIV=63.3%, MViR=36.7% and ViMAC=71%). Mean STS score was 9.2±6.6% (MViV 10.2±6.5%, MViR 8.7±4.7%, ViMAC=8.6±8.2%). All-cause mortality at 4 years was higher for ViMAC and MViR: MViV=6.9% (cardiovascular 3.4%), MViR=48.1% (cardiovascular 18.5%), ViMAC=51.9% (cardiovascular 29.6%), p=0.002 (Figure 1). At 4 years, all survivors had ≤1+ mitral regurgitation and most had none or trace mitral regurgitation (MViV=87.5, MViR=33.3% and ViMAC=100%). Mean mitral valve gradients remained stable (MViV=5.9±2.2 mmHg, MViR= 6.6±5.1 mmHg, ViMAC=5.1±1.0 mmHg), Figure 2. Most survivors experienced significant improvement of symptoms and were in NYHA class I-II at 4-year follow-up (MViV=78.9%, MViR=66.7% and ViMAC=66.7%).

Conclusions

MViV is associated with excellent outcomes at 4 years. MViR and ViMAC were associated with higher mortality at 4 years. However, most survivors in all groups experienced sustained improvement of symptoms and stable THV performance at 4 years. Whether survival bias had an impact on THV performance and improved symptoms at follow-up is not known and deserves further evaluation.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Unrestricted Research Grant from Edwards Lifesciences.

Impact of metformin on the all-cause mortality in diabetic patients hospitalized with acute heart failure

Introduction

Although the hypothesis that metformin is beneficial for diabetic patients with heart failure (HF) has been steadily raised, there have been no solid data on the efficacy of metformin in acute HF patients.

Purpose

We investigated the impact of metformin on all-cause mortality in hospitalized acute HF patients with type 2 diabetes.

Methods

The Korean Acute Heart Failure registry enrolled patients hospitalized for acute HF from 2011 to 2014. Among this cohort, we analyzed patients with diabetes. We investigated all-cause mortality at 1 year after discharge. Propensity score matching (1:1 matching) and Cox proportional hazard models were used to assess difference in all-cause mortality.

Results

The study analyzed 1,976 diabetic patients (median age 72 years, mean left ventricular ejection fraction (LVEF) 34%, 54.5% male). Among them, 712 (36%) patients were on metformin. After 1:1 propensity score matching, 1,424 patients (712 metformin users vs. 712 non-users) were analyzed. During the median follow-up period of 11 months, 146 (21%) metformin non-users died and 108 (15%) metformin users died. Kaplan-Meier curves showed a higher all-cause mortality rate in non-users than in metformin users (Log-rank P=0.0025). After adjustment for clinically relevant variables, metformin was associated with lower risk for all-cause mortality (HR 0.713, 95% CI 0.551–0.922, P=0.01). In subgroup analyses, metformin use was significantly associated with a lower all-cause mortality in higher eGFR group (≥60 ml/min/1.73 m2, HR 0.531, 95% CI 0.357–0.790, P=0.002), but not in lower eGFR group (<60 ml/min/1.73 m2, HR 0.905, 95% CI 0.643–1.275, P=0.569, P-for-interaction=0.033). There was no significant interaction of metformin use for all-cause mortality between the subgroups with LVEF ≤40% and LVEF >40% (P-for-interaction=0.906).

Conclusion

Metformin use was associated with a lower risk for 1-year all-cause mortality in diabetic acute HF patients, especially in high eGFR group.

Funding Acknowledgement

Type of funding sources: None.

Antibody-targeted and streptomycin-chitosan oligosaccharide-modified gold nanoshells for synergistic chemo-photothermal therapy of drug-resistant bacterial infection

Despite the many advanced strategies that are available, rapid gene mutation in multidrug-resistant bacterial infections remains a major challenge. Combining new therapeutic strategies such as chemo-photothermal therapy (PTT) with high antibacterial efficiency against drug-resistant Listeria monocytogenes (LM) is urgently needed. Here, we report synergistic chemo-PTT against drug-resistant LM based on antibody-targeted and streptomycin-chitosan oligosaccharide-modified gold nanoshells (anti-STR-CO-GNSs) as all-in-one nanotheranostic agents for the first time, which was used for accurate antibacterial applications. The anti-STR-CO-GNSs showed excellent photothermal conversion efficiency (31.97%) and were responsive to near-infrared (NIR) and pH dual stimuli-triggered antibiotic release, resulting in outstanding chemo-photothermal effects against LM. In vitro chemo-photothermal effect of anti-STR-CO-GNSs with laser irradiation caused a greater antibacterial effect (1.37%), resulting in more rapid killing of LM and prevention of LM regrowth. Most importantly, the mice receiving the anti-STR-CO-GNSs with laser irradiation specifically at the sites of LM infections healed almost completely, leaving only scars on the surface of the skin and resulting in superior inhibitory effects from combined chemo-PTT. Overall, our findings suggest that chemo-PTT using smart biocompatible anti-STR-CO-GNSs is a favorable potential alternative to combat the increasing threat of drug-resistant LM, which opens a new door for clinical anti-infection therapy in the future.

In vivo mimicking injectable self-setting composite bio-cement: Scanning acoustic diagnosis and biological property evaluation for tissue engineering applications

Injectability and self-setting properties are important factors to increase the efficiency of bone regeneration and reconstruction, thereby reducing the invasiveness of hard tissue engineering procedures. In this study, 63S bioactive glass (BG), nano-hydroxyapatite (n-HAp), alumina, titanium dioxide, and methylene bis-acrylamide (MBAM)-mediated polymeric crosslinking composites were prepared for the formulation of an efficient self-setting bone cement. According to the cytocompatibility and physicochemical analyses, all the samples qualified the standard of the bio-composite materials. They revealed high thermal stability, injectability, and self-setting ability supported by ~ 10.73% (maximum) mass loss, ~ 92-93% injectability and 24 ± 5 min of initial setting time. Moreover, a cellular adhesion and proliferation study was additionally performed with osteoblasts like MG-63 cells, which facilitate pseudopod-like cellular extensions on the BG/n-HAp composite scaffold surface. The SAM study was employed to non-invasively assess the self-setting properties of the composite bio-cement using the post injected distribution and physical properties of the phantom. These results validate the significant potential characteristics of the BG/n-HAp self-setting bio-cement (16:4:2:1) for promising minimal-invasive bone tissue engineering applications.

Effects of an exogenous enzyme preparation extracted from a mixed culture of Aspergillus spp. on lactational performance, metabolism, and digestibility in primiparous and multiparous cows

The objective of this study was to investigate the effects of an exogenous enzyme preparation from Aspergillus oryzae and Aspergillus niger on lactational performance of dairy cows. Forty-eight Holstein cows (32 primiparous and 16 multiparous) averaging (± SD) 36.3 ± 8.7 kg/d milk yield and 141 ± 52 d in milk were enrolled in a 10-wk randomized complete block design experiment (total of 24 blocks) and assigned to 1 of 2 treatments: basal diet, no enzyme supplementation (CON) or the basal diet supplemented with 4.2 g/kg dry matter intake (DMI) of an exogenous enzyme preparation containing amylolytic and fibrolytic activities (ENZ). After a 2-wk covariate period, premixes with the enzyme preparation or control were top-dressed daily by mixing with approximately 500 g of total mixed ration. Production data were collected daily and averaged by week. Milk samples were collected every other week, and milk composition was averaged by week. Blood, fecal, and urine samples were collected over 2 consecutive days at 0, 4, 8, 12, and 36 h after feeding during the last week of the experiment. Compared with CON, cows fed ENZ tended to increase DMI and had increased milk concentrations of true protein, lactose, and other solids. Milk fat content tended to be higher in CON cows. A treatment × parity interaction was found for some of the production variables. Primiparous cows receiving ENZ had greater yields of milk, energy-corrected milk, milk true protein, and lactose compared with CON primiparous cows; these production variables did not differ between treatments for multiparous cows. Intake and total-tract digestibility of nutrients did not differ between treatments. Concentrations of blood glucose and total fatty acids were not affected by ENZ supplementation, but β-hydroxybutyrate concentration tended to be greater in ENZ cows. Overall, the exogenous enzyme preparation used in this study increased milk protein and lactose concentrations in all cows, and milk production in primiparous but not multiparous cows. The differential production response between primiparous and multiparous cows was likely a result of a greater increase in DMI with ENZ supplementation in the younger animals.

Design and Micro-Fabrication of Focused High-Frequency Needle Transducers for Medical Imaging

In this study, we report an advanced fabrication technique to develop a miniature focused needle transducer. Two different types of high-frequency (100 MHz) transducers were fabricated using the lead magnesium niobate-lead titanate (PMN-0.3PT) and lithium niobate (LiNbO3) single crystals. In order to enhance the transducer's performance, a unique mass-spring matching layer technique was adopted, in which gold and parylene play the roles of the mass layer and spring layer, respectively. The PMN-0.3PT transducer had a 103 MHz center frequency with a -6 dB bandwidth of 52%, and a signal-to-noise ratio (SNR) of 42 dB. The center frequency, -6 dB bandwidth, and SNR of the LiNbO3 transducer were 105 MHz, 66%, and 44 dB, respectively. In order to compare and evaluate the transducers' performances, an ultrasonic biomicroscopy (UBM) imaging on the fish eye was performed. The results showed that the LiNbO3 transducer had a better contrast resolution compared to the PMN-0.3PT transducer. The fabricated transducer showed an excellent performance with high-resolution corneal epithelium imaging of the experimental fish eye. These interesting findings are useful for the future biomedical implementation of the fabricated transducers in the field of high-resolution ultrasound imaging and diagnosis purpose.

Characterization of interlimb interaction via transcutaneous spinal stimulation of cervical and lumbar spinal enlargements

The use of transcutaneous electrical spinal stimulation (TSS) to modulate sensorimotor networks after neurological insult has garnered much attention from both researchers and clinicians in recent years. Although many different stimulation paradigms have been reported, the interlimb effects of these neuromodulation techniques have been little studied. The effects of multisite TSS on interlimb sensorimotor function are of particular interest in the context of neurorehabilitation, as these networks have been shown to be important for functional recovery after neurological insult. The present study utilized a condition-test paradigm to investigate the effects of interenlargement TSS on spinal motor excitability in both cervical and lumbosacral motor pools. Additionally, comparison was made between the conditioning effects of lumbosacral and cervical TSS and peripheral stimulation of the fibular nerve and ulnar nerve, respectively. In 16/16 supine, relaxed participants, facilitation of spinally evoked motor responses (sEMRs) in arm muscles was seen in response to lumbosacral TSS or fibular nerve stimulation, whereas facilitation of sEMRs in leg muscles was seen in response to cervical TSS or ulnar nerve stimulation. The decreased latency between TSS- and peripheral nerve-evoked conditioning implicates interlimb networks in the observed facilitation of motor output. The results demonstrate the ability of multisite TSS to engage interlimb networks, resulting in the bidirectional influence of cervical and lumbosacral motor output. The engagement of interlimb networks via TSS of the cervical and lumbosacral enlargements represents a feasible method for engaging spinal sensorimotor networks in clinical populations with compromised motor function.NEW & NOTEWORTHY Bidirectional interlimb modulation of spinal motor excitability can be evoked by transcutaneous spinal stimulation over the cervical and lumbosacral enlargements. Multisite transcutaneous spinal stimulation engages spinal sensorimotor networks thought to be important in the recovery of function after spinal cord injury.

Full-view in vivo skin and blood vessels profile segmentation in photoacoustic imaging based on deep learning

Photoacoustic (PA) microscopy allows imaging of the soft biological tissue based on optical absorption contrast and spatial ultrasound resolution. One of the major applications of PA imaging is its characterization of microvasculature. However, the strong PA signal from skin layer overshadowed the subcutaneous blood vessels leading to indirectly reconstruct the PA images in human study. Addressing the present situation, we examined a deep learning (DL) automatic algorithm to achieve high-resolution and high-contrast segmentation for widening PA imaging applications. In this research, we propose a DL model based on modified U-Net for extracting the relationship features between amplitudes of the generated PA signal from skin and underlying vessels. This study illustrates the broader potential of hybrid complex network as an automatic segmentation tool for the in vivo PA imaging. With DL-infused solution, our result outperforms the previous studies with achieved real-time semantic segmentation on large-size high-resolution PA images.

A Flexible, Wearable, and Wireless Biosensor Patch with Internet of Medical Things Applications

Monitoring the vital signs and physiological responses of the human body in daily activities is particularly useful for the early diagnosis and prevention of cardiovascular diseases. Here, we proposed a wireless and flexible biosensor patch for continuous and longitudinal monitoring of different physiological signals, including body temperature, blood pressure (BP), and electrocardiography. Moreover, these modalities for tracking body movement and GPS locations for emergency rescue have been included in biosensor devices. We optimized the flexible patch design with high mechanical stretchability and compatibility that can provide reliable and long-term attachment to the curved skin surface. Regarding smart healthcare applications, this research presents an Internet of Things-connected healthcare platform consisting of a smartphone application, website service, database server, and mobile gateway. The IoT platform has the potential to reduce the demand for medical resources and enhance the quality of healthcare services. To further address the advances in non-invasive continuous BP monitoring, an optimized deep learning architecture with one-channel electrocardiogram signals is introduced. The performance of the BP estimation model was verified using an independent dataset; this experimental result satisfied the Association for the Advancement of Medical Instrumentation, and the British Hypertension Society standards for BP monitoring devices. The experimental results demonstrated the practical application of the wireless and flexible biosensor patch for continuous physiological signal monitoring with Internet of Medical Things-connected healthcare applications.

Computational analysis of drug free silver triangular nanoprism theranostic probe plasmonic behavior for in-situ tumor imaging and photothermal therapy

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Designing drug-free polyvinyl alcohol coated stable silver triangular nano-prisms (PVA-SNT).

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Computational simulation of optical and photothermal properties with high in vivo experimental similarity.

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Stable PVA-SNT enables photoacoustic imaging-guided photothermal therapy of breast cancer.

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PVA-SNT exhibits enhanced photostability and high photothermal conversion efficiency.

Introduction

The advanced features of plasmonic nanomaterials enable initial high accuracy detection with different therapeutic intervention. Computational simulations could estimate the plasmonic heat generation with a high accuracy and could be reliably compared to experimental results. This proposed combined theoretical-experimental strategy may help researchers to better understand other nanoparticles in terms of plasmonic efficiency and usability for future nano-theranostic research.

Objectives

To develop innovative computationally-driven approach to quantify any plasmonic nanoparticles photothermal efficiency and effects before their use as therapeutic agents.

Methods

This report introduces drug free plasmonic silver triangular nanoprisms coated with polyvinyl alcohol biopolymer (PVA-SNT), for in vivo photoacoustic imaging (PAI) guided photothermal treatment (PTT) of triple-negative breast cancer mouse models. The synthesized PVA-SNT nanoparticles were characterized and a computational electrodynamic analysis was performed to evaluate and predict the optical and plasmonic photothermal properties. The in vitro biocompatibility and in vivo tumor abalation study was performed with MDA-MB-231 human breast cancer cell line and in nude mice model.

Results

The drug free 140 μg∙mL⁻¹ PVA-SNT nanoparticles with 1.0 W∙cm⁻² laser irradiation for 7 min proved to be an effective and optimized theranostic approach in terms of PAI guided triple negative breast cancer treatment. The PVA-SNT nanoparticles exhibits excellent biosafety, photostability, and strong efficiency as PAI contrast agent to visualize tumors. Histological analysis and fluorescence-assisted cell shorter assay results post-treatment apoptotic cells, more importantly, it shows substantial damage to in vivo tumor tissues, killing almost all affected cells, with no recurrence.

Conclusion

This is a first complete study on computational simulations to estimate the plasmonic heat generation followed by drug free plasmonic PAI guided PTT for cancer treatment. This computationally-driven theranostic approach demonstrates an innovative thought regarding the nanoparticles shape, size, concentration, and composition which could be useful for the prediction of photothermal heat generation in precise nanomedicine applications.

Factors associated with treatment escalation among MS specialists and general neurologists: Results from an International cojoint study

BACKGROUND

Previous studies in multiple sclerosis (MS) showed that therapeutic inertia (TI) affects 60-90% of neurologists and up to 25% of daily treatment decisions. The objective of this study was to determine the most common factors and attribute levels associated with decisions to treatment escalation in an international study in MS care.

METHODS

300 neurologists with MS expertise from 20 countries were invited to participate. Participants were presented with 12 pairs of simulated MS patient profiles described by 13 clinically relevant factors. We used disaggregated discrete choice experiments to estimate the weight of factors and attributes affecting physicians' decisions when considering treatment selection. Participants were asked to select the ideal candidate for treatment escalation from modest to higher-efficacy therapies.

RESULTS

Overall, 229 neurologists completed the study (completion rate: 76.3%). The top 3 weighted factors associated with treatment escalation were: previous relapses (20%), baseline expanded disability status scale [EDSS] (18%), and MRI activity (13%). Patient demographics and desire for pregnancy had a modest influence (≤ 3%). We observed differences in the weight of factors associated with treatment escalation between MS specialists and non-MS specialists.

CONCLUSIONS

Our results provide critical information on factors influencing neurologists' treatment decisions and should be applied to continuing medical education strategies.

Suspected human intravenous immunoglobulin-induced acute haemolytic anaemia in a dog

A 2-year-old mixed breed dog presented with a 1-year history of crust and erosion on the nasal planum. Because histopathological examination revealed ruptured intraepidermal pustules and superficial dermal inflammation, the dog was diagnosed with pemphigus foliaceus. Human intravenous immunoglobulin was administered in two consecutive doses of 0.5 g/kg/day due to poor therapeutic response to previous immunosuppressive therapy. From Day 3 after the first dose of human intravenous immunoglobulin, tachypnoea, pale mucous membrane, haemoglobinuria and haemoglobinemia were observed, thus confirming haemolytic anaemia. Other drug-induced haemolytic anaemias were excluded because no additional drugs had been administered before the haemolysis occurred. Immune-mediated haemolytic anaemia was also excluded because the direct antiglobulin test was negative. Two transfusions were performed, and haemolysis was not observed from Day 4 of haemolytic anaemia onset. In conclusion, human intravenous immunoglobulin-induced haemolytic anaemia should be considered in dogs that develop haemolysis following the administration of human intravenous immunoglobulin.

Comparing noninvasive sampling techniques with standard cannula sampling method for ruminal microbial analysis

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Ruminal cannula is the gold standard for sampling rumen contents but is limited to few animals.

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Noninvasive methods are needed as proxy for cannula to enable sampling larger numbers of cows.

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Saliva, rumination bolus, tube-derived rumen samples, and feces were compared with cannula samples.

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Microbial community in the solid fraction of tube samples mirrored that of cannula samples.

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Rumination bolus may serve as a proxy for cannula samples under certain conditions.

Rumen microbes play an important role in the conversion of indigestible plant material to energy and protein in dairy cows. Sampling for ruminal contents via cannula is considered the gold standard technique for microbial analysis, but the technique requires ruminally cannulated animals and specialized animal facilities. The purpose of this study was to determine whether other sampling methods and locations along the digestive tract may serve as noninvasive proxies to the cannula method for microbial analysis. Six ruminally cannulated lactating Holstein dairy cows were adapted to a standard total mixed ration for 2 wk and sampled during the third week. Sampling locations and methods included salivary content, rumination bolus (regurgitated digesta collected from the cow's mouth), feces, and rumen contents via stomach tube and cannula. Stomach tube and cannula samples differ in proportions of solid and liquid material and were therefore separated into whole (as collected), liquid, and solid fractions. Samples were collected at 0 (before feeding), 2, 4, 6, 8, and 12 h after feeding over 2 d. All samples were extracted for total genomic DNA and selected samples for metabolically active DNA (RNA), PCR-amplified for the V1-V2 region of the 16S rRNA bacterial gene, and analyzed for bacterial diversity using the QIIME2 pipeline followed by statistical analysis in R (https://www.R-project.org/). In DNA-based analysis, at the community level, saliva, rumination bolus, and fecal samples clustered in separate groups, whereas all fractions of stomach tube and cannula samples clustered together, indicating that microbial communities of stomach tube and cannula samples were homogeneous. Rumination bolus samples at 6, 8, and 12 h after feeding clustered with stomach tube and cannula samples, indicating that rumination bolus samples may be an alternative for cannula samples; however, time of sampling is critical for sampling of bolus digesta. Results of the RNA-based analysis of rumination bolus samples and solid samples from cannula and stomach tube at 0 and 6 h after feeding were similar. We concluded that the solid fraction of samples obtained via the stomach tube method may serve as a proxy for the solid fraction of whole ruminal contents obtained via cannula for DNA-based microbial investigations. Both rumination bolus and stomach tube solid samples may serve as proxies for cannula solid samples for RNA-based microbial analysis.