Manifold-based denoising for Ferumoxytol-enhanced 3D cardiac cine MRI.

The two-dimensional (2D) cine cardiovascular magnetic resonance (CMR) technique is the reference standard for assessing cardiac function. However, one challenge with 2D cine is that the acquisition time for the whole cine stack is long and requires multiple breath holds, which may not be feasible for pediatric or ill patients. Though single breath-hold multi-slice cine may address the issue, it can only acquire low-resolution images, and hence, affect the accuracy of cardiac function assessment. To address these challenges, a Ferumoxytol-enhanced, free breathing, isotropic high-resolution 3D cine technique was developed. The method produces high-contrast cine images with short acquisition times by using compressed sensing together with a manifold-based method for image denoising. This study included fifteen patients (9.1 $ \pm $ 5.6 yrs.) who were referred for clinical cardiovascular magnetic resonance imaging (MRI) with Ferumoxytol contrast and were prescribed the 3D cine sequence. The data was acquired on a 1.5T scanner. Statistical analysis shows that the manifold-based denoised 3D cine can accurately measure ventricular function with no significant differences when compared to the conventional 2D breath-hold (BH) cine. The multiplanar reconstructed images of the proposed 3D cine method are visually comparable to the golden standard 2D BH cine method in terms of clarity, contrast, and anatomical precision. The proposed method eliminated the need for breath holds, reduced scan times, enabled multiplanar reconstruction within an isotropic data set, and has the potential to be used as an effective tool to access cardiovascular conditions.

Redox mechanisms of environmental toxicants on male reproductive function.

Humans and wildlife, including domesticated animals, are exposed to a myriad of environmental contaminants that are derived from various human activities, including agricultural, household, cosmetic, pharmaceutical, and industrial products. Excessive exposure to pesticides, heavy metals, and phthalates consequently causes the overproduction of reactive oxygen species. The equilibrium between reactive oxygen species and the antioxidant system is preserved to maintain cellular redox homeostasis. Mitochondria play a key role in cellular function and cell survival. Mitochondria are vulnerable to damage that can be provoked by environmental exposures. Once the mitochondrial metabolism is damaged, it interferes with energy metabolism and eventually causes the overproduction of free radicals. Furthermore, it also perceives inflammation signals to generate an inflammatory response, which is involved in pathophysiological mechanisms. A depleted antioxidant system provokes oxidative stress that triggers inflammation and regulates epigenetic function and apoptotic events. Apart from that, these chemicals influence steroidogenesis, deteriorate sperm quality, and damage male reproductive organs. It is strongly believed that redox signaling molecules are the key regulators that mediate reproductive toxicity. This review article aims to spotlight the redox toxicology of environmental chemicals on male reproduction function and its fertility prognosis. Furthermore, we shed light on the influence of redox signaling and metabolism in modulating the response of environmental toxins to reproductive function. Additionally, we emphasize the supporting evidence from diverse cellular and animal studies.

Dobutamine Stress Cardiovascular Magnetic Resonance Derived 2-Dimension Feature Tracking Strain Analysis in Pediatric Population with Anomalous Aortic Origin of Right Coronary Artery.

Anomalous aortic origin of right coronary artery (AAORCA) is associated with myocardial ischemia and sudden cardiac arrest/death. Risk stratification remains challenging and relies upon provocative test results. This study describes the utility of dobutamine stress cardiovascular magnetic resonance (DSCMR) and potential benefit of strain analysis in children with AAORCA. All patients less than 21 years of age with AAORCA who underwent DSCMR between July 2018 and December 2022 were included. Visual wall motion abnormalities (VWMA) at rest and during protocolized increments of dobutamine infusion were assessed. Regional and global left ventricular circumferential (GCS) and radial (GRS) strain using 2-dimension Feature tracking (2D-FT) analysis (cvi42, Circle Cardiovascular Imaging Inc.) were calculated at rest and peak response. Of the total 54 DSCMR studies performed in 51 children with median age (IQR) of 13.5 (11-15) years, FT analysis was reliably performed in 52 (96%) studies. None had VWMA. The absolute change in GCS and GRS from rest to peak dobutamine stress was 4% (1-6%) and 11% (4-18%), respectively. There was no significant difference in GCS and GRS in patients with exertional symptoms vs no/non-exertional symptoms as well as between those considered to be high-risk vs low-risk anatomical features. DSCMR-derived 2D-FT strain analysis is feasible to assess myocardial deformation in children with AAORCA and may enhance this method of provocative testing. Although there were no statically significant differences in GCS and GRS values between high and low-risk subgroups, the absolute change in GCS between rest and peak stress is diminished when compared to normal adult reports.

Artificial Intelligence to derive aligned strain in cine CMR to detect patients with myocardial fibrosis: an open and scrutinizable approach.

Cine Cardiac Magnetic Resonance (CMR) is the gold standard for cardiac function evaluation, incorporating ejection fraction (EF) and strain as vital indicators of abnormal deformation. Rare pathologies like Duchenne muscular dystrophies (DMD) are monitored with repeated late gadolinium-enhanced (LGE) CMR for identification of myocardial fibrosis. However, it is judicious to reduce repeated gadolinium exposure and rather employ strain analysis from cine CMR. This solution is limited so far since full strain curves are not comparable between individual cardiac cycles and current practice mainly neglects diastolic deformation patterns. Our novel Deep Learning-based approach derives strain values aligned by key frames throughout the cardiac cycle. In a reproducibility scenario (57+82 patients), our results reveal five times more significant differences (22 vs. 4) between patients with scar and without, enhancing scar detection by +30%, improving detection of patients with preserved EF by +61%, with an overall sensitivity/specificity of 82/81%.

Cardiovascular remodelling in response to exercise training in patients after the Fontan procedure: a pilot study.

BACKGROUND: The cardiovascular adaptations associated with structured exercise training in Fontan patients remain unknown. We hypothesised that short-term training causes cardiac remodelling and parallel improvement in maximal exercise capacity (VO2 max) in these patients. METHODS AND RESULTS: Five patients, median age 19.5 (17.6-21.3) years, with a history of Fontan operation meeting inclusion/exclusion criteria, participated in a 3-month training programme designed to improve endurance. Magnetic resonance images for assessment of cardiac function, fibrosis, cardiac output, and liver elastography to assess stiffness were obtained at baseline and after training. Maximal exercise capacity (VO2 max) and cardiac output Qc (effective pulmonary blood flow) at rest and during exercise were measured (C2H2 rebreathing) at the same interval. VO2 max increased from median (IQR) 27.2 (26-28.7) to 29.6 (28.5-32.2) ml/min/kg (p = 0.04). There was an improvement in cardiac output (Qc) during maximal exercise testing from median (IQR) 10.3 (10.1-12.3) to 12.3 (10.9-14.9) l/min, but this change was variable (p = 0.14). Improvement in VO2 max correlated with an increase in ventricular mass (r = 0.95, p = 0.01), and improvement in Quality-of-life inventory (PedsQL) Cardiac scale scores for patient-reported symptoms (r = 0.90, p = 0.03) and cognitive problems (r = 0.89, p = 0.04). The correlation between VO2 max and Qc showed a positive trend but was not significant (r = 0.8, p = 0.08). No adverse cardiac or liver adaptations were noted. CONCLUSION: Short-term training improved exercise capacity in this Fontan pilot without any adverse cardiac or liver adaptations. These results warrant further study in a larger population and over a longer duration of time. TRIAL REGISTRATION NUMBER: NCT03263312, Unique Protocol ID: STU 122016-037; Registration Date: 18 January, 2017.

Time-Resolved 3D cardiopulmonary MRI reconstruction using spatial transformer network.

The accurate visualization and assessment of the complex cardiac and pulmonary structures in 3D is critical for the diagnosis and treatment of cardiovascular and respiratory disorders. Conventional 3D cardiac magnetic resonance imaging (MRI) techniques suffer from long acquisition times, motion artifacts, and limited spatiotemporal resolution. This study proposes a novel time-resolved 3D cardiopulmonary MRI reconstruction method based on spatial transformer networks (STNs) to reconstruct the 3D cardiopulmonary MRI acquired using 3D center-out radial ultra-short echo time (UTE) sequences. The proposed reconstruction method employed an STN-based deep learning framework, which used a combination of data-processing, grid generator, and sampler. The reconstructed 3D images were compared against the start-of-the-art time-resolved reconstruction method. The results showed that the proposed time-resolved 3D cardiopulmonary MRI reconstruction using STNs offers a robust and efficient approach to obtain high-quality images. This method effectively overcomes the limitations of conventional 3D cardiac MRI techniques and has the potential to improve the diagnosis and treatment planning of cardiopulmonary disorders.

EMO-MoviNet: Enhancing Action Recognition in Videos with EvoNorm, Mish Activation, and Optimal Frame Selection for Efficient Mobile Deployment.

The primary goal of this study is to develop a deep neural network for action recognition that enhances accuracy and minimizes computational costs. In this regard, we propose a modified EMO-MoviNet-A2* architecture that integrates Evolving Normalization (EvoNorm), Mish activation, and optimal frame selection to improve the accuracy and efficiency of action recognition tasks in videos. The asterisk notation indicates that this model also incorporates the stream buffer concept. The Mobile Video Network (MoviNet) is a member of the memory-efficient architectures discovered through Neural Architecture Search (NAS), which balances accuracy and efficiency by integrating spatial, temporal, and spatio-temporal operations. Our research implements the MoviNet model on the UCF101 and HMDB51 datasets, pre-trained on the kinetics dataset. Upon implementation on the UCF101 dataset, a generalization gap was observed, with the model performing better on the training set than on the testing set. To address this issue, we replaced batch normalization with EvoNorm, which unifies normalization and activation functions. Another area that required improvement was key-frame selection. We also developed a novel technique called Optimal Frame Selection (OFS) to identify key-frames within videos more effectively than random or densely frame selection methods. Combining OFS with Mish nonlinearity resulted in a 0.8-1% improvement in accuracy in our UCF101 20-classes experiment. The EMO-MoviNet-A2* model consumes 86% fewer FLOPs and approximately 90% fewer parameters on the UCF101 dataset, with a trade-off of 1-2% accuracy. Additionally, it achieves 5-7% higher accuracy on the HMDB51 dataset while requiring seven times fewer FLOPs and ten times fewer parameters compared to the reference model, Motion-Augmented RGB Stream (MARS).

On the application of pseudo-continuous arterial spin labeled MRI for pulmonary perfusion imaging.

PURPOSE: To evaluate different approaches for the effective assessment of pulmonary perfusion with a pseudo-continuous arterial spin labeled (pCASL) MRI. MATERIALS AND METHODS: Four different approaches were evaluated: 1) Cardiac-triggered inferior vena cava (IVC) labeling; 2) IVC labeling with cardiac-triggered acquisition; 3) Right pulmonary artery (RPA) labeling with cardiac-triggered acquisition; and 4) Cardiac-triggered RPA labeling with background suppression (BGS). Each approach was evaluated in 5 healthy volunteers (n = 20) using coefficient of variation (COV) across averages. Approach 4 was also compared against a flow alternating inversion recovery (FAIR). RESULTS: The IVC labeling (Approach 1) achieved perfusion-weighted images of both lungs, although this approach was more sensitive to variations in heart rate. Cardiac-triggered acquisitions using IVC (Approach 2) and RPA (Approach 3) labeling improved signal consistencies, but were incompatible with BGS. The cardiac-triggered RPA labeling with BGS (Approach 4) achieved a COV of 0.34 ± 0.03 (p < 0.05 compared to IVC labeling approaches) and resulted in perfusion value of 434 ± 64 mL/100 g/min, which was comparable to 451 ± 181 mL/100 g/min measured by FAIR (p = 0.82). DISCUSSION: Pulmonary perfusion imaging using pCASL-MRI is highly sensitive to cardiac phase, and requires approaches to minimize flow-induced signal variations. Cardiac-triggered RPA labeling with BGS achieves reduced COV and enables robust pulmonary perfusion imaging.

Calpain signaling: from biology to therapeutic opportunities in neurodegenerative disorders.

Neurodegenerative disorders represent a major and growing healthcare challenge globally. Among the numerous molecular pathways implicated in their pathogenesis, calpain signaling has emerged as a crucial player in neuronal dysfunction and cell death. Calpain is a family of calcium-dependent cysteine proteases that is involved in many biological processes, such as signal transduction, cytoskeleton remodeling, and protein turnover. Dysregulation of calpain activation and activity has been associated with several neurodegenerative diseases, including Alzheimer's, Parkinson's, and Huntington's diseases. Understanding the intricate structure of calpains is crucial for unraveling their roles in cellular physiology and their implications in pathology. In addition, the identification of diverse abnormalities in both humans and other animal models with deficiencies in calpain highlights the significant progress made in understanding calpain biology. In this comprehensive review, we delve into the recent roles attributed to calpains and provide an overview of the mechanisms that govern their activity during the progression of neurodegenerative diseases. The possibility of utilizing calpain inhibition as a potential therapeutic approach for treating neuronal dysfunctions in neurodegenerative disorders would be an area of interest in future calpain research.

Tolerability and efficacy of a reduced dose adenosine stress cardiac magnetic resonance protocol under general anesthesia in infants and children.

BACKGROUND: Intravenous adenosine induces pharmacological stress by causing vasodilatation and thus carries the risk of severe hypotension when combined with vasodilatory effects of anesthetic agents. OBJECTIVE: This study describes our experience with a reduced dose adenosine cardiac magnetic resonance imaging (MRI) protocol in young children under general anesthesia (GA). MATERIALS AND METHODS: This is a retrospective report of all patients from birth to 18 years who underwent adenosine stress cardiac MRI under GA between August 2018 and November 2022. Based on our anecdotal experience of severe adverse effects in patients receiving adenosine infusion under GA and in discussion with the pediatric anesthesia team, we developed a modified protocol starting at a dose of 110 mcg/kg/min with incremental escalation to a full dose of 140 mcg/kg/min to achieve desired hemodynamic effect. RESULTS: Twenty-two children (mean age 6.5 years, mean weight 28 kg) satisfied the inclusion criteria. The diagnoses included Kawasaki disease (7), anomalous aortic origin of left coronary artery (3), anomalous aortic origin of right coronary artery (2), coronary fistula (3), repaired d-transposition of great arteries (2), repaired anomalous left coronary artery from pulmonary artery (2), repaired truncus arteriosus with left coronary artery occlusion (1), extracardiac-Fontan with left coronary artery myocardial bridge (1), and post heart transplantation (1). Nine patients needed dose escalation beyond 110 mcg/kg/min. Two patients had transient hypotension during testing (systemic blood pressure drop > 25 mmHg). No patient developed significant heart block or bronchospasm. Six patients (repeat study in one) demonstrated inducible perfusion defects (27%) on stress perfusion sequences-5 of whom had confirmed significant coronary abnormalities on angiography or direct surgical inspection. CONCLUSION: A reduced/incremental dose adenosine stress cardiac MRI protocol under GA in children is safe and feasible. This avoids severe hypotension which is both unsafe and may result in inaccurate data.

Unraveling the harmful effect of oxidative stress on male fertility: A mechanistic insight.

Male infertility is a widely debated issue that affects males globally. There are several mechanisms involved. Oxidative stress is accepted to be the main contributing factor, with sperm quality and quantity affected by the overproduction of free radicals. Excess reactive oxygen species (ROS) cannot be controlled by the antioxidant system and, thus, potentially impact male fertility and hamper sperm quality parameters. Mitochondria are the driving force of sperm motility; irregularities in their function may lead to apoptosis, alterations to signaling pathway function, and, ultimately, compromised fertility. Moreover, it has been observed that the prevalence of inflammation may arrest sperm function and the production of cytokines triggered by the overproduction of ROS. Further, oxidative stress interacts with seminal plasma proteomes that influence male fertility. Enhanced ROS production disturbs the cellular constituents, particularly DNA, and sperms are unable to impregnate the ovum. Here, we review the latest information to better understand the relationship between oxidative stress and male infertility, the role of mitochondria, the cellular response, inflammation and fertility, and the interaction of seminal plasma proteomes with oxidative stress, as well as highlight the influence of oxidative stress on hormones; collectively, all of these factors are assumed to be important for the regulation of male infertility. This article may help improve our understanding of male infertility and the strategies to prevent it.

Association of faecal volatiles and steroids with behavioural expression during oestrous cycle of sheep (Ovis aries).

This study was investigated to determine the faecal volatiles, steroid hormones and their correlation with behavioural signs during oestrous cycle in sheep (Ovis aries). This experiment was monitored from pro-oestrous to met-oestrous phases for correlation of endocrine dependence biochemical constituents in faeces and blood to detection of oestrous biomarkers. Medroxyprogesterone acetate sponges were used for 8 days to bring uniformity of oestrus in sheep. Faeces were collected during different phases of cycle and subjected to determination of fatty acids, minerals, oestrogens and progesterone analysis. Likewise, blood samples were also obtained for enzymatic and no-enzymatic antioxidants. The results revealed that faecal progesterone and oestrogen levels significantly increased during pro-oestrous and oestrous phase, respectively (p < .05). The blood plasma enzymatic levels showed significant demarcation during the oestrous phase than other periods (p < .05). There were also reported marked variations in volatile fatty acids across different phases of the oestrous cycle. Interestingly, methyl octanoate, methyl cis-10 pentadecenoate and methyl heptadecanoate volatiles were found to be specific to oestrus period. In addition, methyl hexanoate, methyl palmitoleate and methyl cis-9 oleate were identified in met-oestrus, indicating their possible role to be an oestrous biomarker. It is concluded that the pattern of volatile compounds and faecal steroids, in association with behavioural patterns, could be measured as a non-invasive method of heat detection in sheep.

Antimicrobial Activities and Biopreservation Potential of Lactic Acid Bacteria (LAB) from Raw Buffalo (Bubalus bubalis) Milk.

The aim of this study was to investigate the antimicrobial and biopreservation potential of lactic acid bacteria. The potential probiotic culture inhibited the growth of gram-positive and gram-negative foodborne pathogens in agar spot assay with inhibition zones ranging from 10 to 21 mm in diameter. The strains showed coaggregation capabilities ranging from 7 to 71% with tested food pathogens including Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Salmonella enterica subsp. enterica serovar Typhimurium. The effect of cell-free supernatants on the release of 260 nm absorbing material, especially nucleic acids, was evaluated and indicated the antagonistic activity on foodborne pathogens, the highest being Lactobacillus paraplantarum against E. coli (3.77) and S. aureus (3.86) after 60 min. The effect of cell-free supernatant (CFS) on the growth of pathogens showed that Lactobacillus paraplantarum 11 and L. pentosus 93 had the highest inhibitory activity against tested strains. The biopreservation assay indicated that the potential probiotic strains Lactobacillus paraplantarum 11 (BT), Lactiplantibacillus plantarum 19, Lactobacillus pentosus 42, Limosilactobacillus fermentum 60, Lactobacillus pentosus 93, and Limosilactobacillus reuteri 112 were effective in reducing the Listeria monocytogenes population in raw buffalo milk. Complete Listeria monocytogenes inhibition was observed after 6-8 days. This study showed that probiotic LAB from buffalo milk have antimicrobial and biopreservation potential; these strains have the potential to be utilized as biopreservative agents in food products.

Effect of dietary protein on growth performance, and serum biochemical index in late pregnant Hu ewes and their offspring.

The purpose of this study was to investigate the effects of different protein levels in late pregnancy on ewe and lamb growth performance, serum biochemical indexes. Thirty-three ewes (46.4 ± 1.38 kg initial weight) were randomly divided into 3 groups, with 11 ewes in each group. The protein levels of three diets formulated to provide components to meet 10.00 MJ/kg ME requirements diets were: 10.12%, 11.26%, 12.4%. Ewes were raised from the 90th day of pregnancy to the end of delivery, and the lambs were weaned at 60 days. Dietary protein levels had significant effects on blood urea nitrogen, glucose, ammonia nitrogen and triglyceride of ewes (p < 0.05). The height, chest depth, chest circumference, straight crown hip length and curved crown hip length of lambs decreased at first and then increased with the increase of protein. The body length, chest circumference, head width and head length of weaned lambs decreased at first and then increased with the increase of protein. The results showed that when the dietary protein level was increased to 12.4%, the amino acid, glucose and fat metabolism of ewes were affected. The body size development of lambs was better than 10.12% and 11.26% proteins.

Society for Cardiovascular Magnetic Resonance 2022 Cases of SCMR case series.

"Cases of SCMR" is a case series on the SCMR website (https://www.scmr.org) for the purpose of education. The cases reflect the clinical presentation, and the use of cardiovascular magnetic resonance (CMR) in the diagnosis and management of cardiovascular disease. The 2022 digital collection of cases are presented in this manuscript.