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•A markerless strategy to support diagnosis of Parkinson’s disease from gait videos.•Spatiotemporal saliency maps that stand out parkinsonian patterns in gait videos.•The model ...highlights spatiotemporal patterns of legs during the single support phase.•The approach achieves 94.89% of accuracy in Parkinson’s disease classification.
Parkinson’s disease (PD) lacks a definitive diagnosis, with the observation of motion patterns being the main method of characterizing disease progression and planning patient treatments. Among PD observations, gait motion patterns, such as step length, flexed posture, and bradykinesia, support the characterization of disease progression. However, this analysis is usually performed with marker-based protocols, which affect the gait and localized segment patterns during locomotion. This work introduces a 3D convolutional gait representation for automatic PD classification that identifies the spatio-temporal patterns used for classification. This approach allows us to obtain an explainable model that classifies markerless sequences and describes the main learned spatio-temporal regions associated with abnormal patterns in a particular video. Initially, a spatio-temporal convolutional network is trained from a set of raw videos and optical flow fields. Then, a PD prediction is obtained from the motion patterns learned by the trained model. Finally, saliency maps, which highlight abnormal motion patterns, are obtained by retro-propagating the output prediction up to the input volume through two different stages: an embedded back-tracking and a pseudo-deconvolution process. From a total of 176 videos from 22 patients, the resulting salient maps highlight lower limb patterns possibly related to step length and speed. In control subjects, the saliency maps highlight the head and trunk posture. The proposed approach achieved an average accuracy score of 94.89%.
Abstract
To investigate the role of NLRP3 inflammasome in muscular aging, we evaluated here the morphological and functional markers of sarcopenia in the NLRP3-knockout mice, as well as the ...beneficial effect of melatonin supplementation. The gastrocnemius muscles of young (3 months), early-aged (12 months), and old-aged (24 months) NLRP3-knockout female mice were examined. Moreover, locomotor activity and apoptosis were assessed. The results revealed early markers of sarcopenia at the age of 12 months, including reduction of lactate, ratio of muscle weight to body weight, muscle fibers number, and mitochondrial number. Increased interstitial tissues, apoptosis, and muscle fibers area, as well as mitochondrial damage were detected, with little muscular activity effects. In the old-aged, these alterations progressed with a reduction in locomotor activity, mitochondrial cristae destruction, nuclear fragmentation, tubular aggregates (TAs) formation, and increased frailty index. Oral melatonin supplementation preserved the normal muscular structure, muscle fibers number, and muscular activity in old age. Melatonin enhanced lactate production, recovered mitochondria, inhibited TAs formation, reduced apoptosis, and normalized frailty index. The fewer sarcopenic changes as well as the highly detectable prophylactic effects of melatonin treatment reported here in the muscle of NLRP3-knockout mice comparing with that previously detected in wild-type mice, confirming NLRP3 inflammasome implication in muscular aging and sarcopenia onset and progression.
The oncostatic effects of melatonin correlate with increased reactive oxygen species (ROS) levels, but how melatonin induces this ROS generation is unknown. In the present study, we aimed to ...elucidate the two seemingly opposing actions of melatonin regarding its relationship with free radicals. We analyzed the effects of melatonin on head and neck squamous cell carcinoma cell lines (Cal‐27 and SCC‐9), which were treated with 0.5 or 1 mM melatonin. We further examined the potential effects of melatonin to induce ROS and apoptosis in Cal‐27 xenograft mice. Here we report that melatonin mediates apoptosis in head and neck cancer by driving mitochondrial reverse electron transport (RET) to induce ROS production. Melatonin‐induced changes in tumoral metabolism led to increased mitochondrial activity, which, in turn, induced ROS‐dependent mitochondrial uncoupling. Interestingly, mitochondrial complex inhibitors, including rotenone, abolished the ROS elevation indicating that melatonin increased ROS generation via RET. Melatonin also increased membrane potential and CoQ10H2/CoQ10 ratio to elevate mitochondrial ROS production, which are essential conditions for RET. We found that genetic manipulation of cancer cells with alternative oxidase, which transfers electrons from QH2 to oxygen, inhibited melatonin‐induced ROS generation, and apoptosis. RET restored the melatonin‐induced oncostatic effect, highlighting the importance of RET as the site of ROS production. These results illustrate that RET and ROS production are crucial factors in melatonin's effects in cancer cells and establish the dual effect of melatonin in protecting normal cells and inducing apoptosis in cancer cells.
The exceptional abilities of stink bugs (Hemiptera: Pentatomidae) to colonize a diverse group of plants have been attributed to the feeding behaviors and the functions of the salivary complex of ...these insects. Here, we describe the ultrastructure of the salivary glands of the Neotropical brown stink bug, Euschistus heros, which is a major component of the pentatomid pest complex on soybeans, Glycine max, in the neotropics. Our results revealed a salivary gland complex consisting of two lobes (i.e., anterior and posterior), with a constriction between them (i.e., the hilum), in which the salivary and accessory gland ducts are inserted. The principal gland epithelium has a single layer of cells lining an enlarged lumen filled with saliva, and these cells are cuboidal, rich in rough endoplasmic reticulum and secretory vesicles, with well-developed nuclei, all of which are typical features of protein-secreting cells. We report, for the first time in insects, the presence of a layer of muscle cells surrounding the columnar hilum epithelium. The accessory salivary gland cells are cuboidal with nuclei containing condensed chromatin and cytoplasm rich in vacuoles and rough endoplasmic reticulum, indicating the potential involvement of these glands in water transport/secretion. The lumen content of each lobe of the principal gland suggests that the lobes produce different compounds. Thus, our results suggest that the E. heros salivary complex might have unconventional mechanisms to mix/release saliva, which might help explain the polyphagous abilities of these insects.
The gastrocnemius muscle (GM) of young (3months) and aged (12months) female wild-type C57/BL6 mice was examined by light and electron microscopy, looking for the presence of structural changes at ...early stage of the aging process. Morphometrical parameters including body and gastrocnemius weights, number and type of muscle fibers, cross section area (CSA), perimeter, and Feret's diameter of single muscle fiber, were measured. Moreover, lengths of the sarcomere, A-band, I-band, H-zone, and number and CSA of intermyofibrillar mitochondria (IFM), were also determined. The results provide evidence that 12month-old mice had significant changes on skeletal muscle structure, beginning with the reduction of gastrocnemius weight to body weight ratio, compatible with an early loss of skeletal muscle function and strength. Moreover, light microscopy revealed increased muscle fibers size, with a significant increase on their CSA, perimeter, and diameter of both type I and type II muscle fibers, and a reduction in the percentage of muscle area occupied by type II fibers. Enhanced connective tissue infiltrations, and the presence of centrally nucleated muscle fibers, were also found in aged mice. These changes may underlie an attempt to compensate the loss of muscle mass and muscle fibers number. Furthermore, electron microscopy discovered a significant age-dependent increase in the length of sarcomeres, I and H bands, and reduction on the overlapped actin/myosin length, supporting contractile force loss with age. Electron microscopy also showed an increased number and CSA of IFM with age, which may reveal more endurance at 12months of age. Together, mice at early stage of aging already show significant changes in gastrocnemius muscle morphology and ultrastructure that are suggestive of the onset of sarcopenia.
•Identification of early signs of aging in mouse gastrocnemius muscle•Signs of degeneration, reduction of type II fibers, and centrally located nuclei•Age-dependent increase in sarcomere length, I and H bands•Increased number and CSA of intermyofibrillar mitochondria
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•Lactate-based H2-fermentation systems are extensively reviewed.•Substrate features, culture conditions and biological factors are discussed in detail.•Lactate-to-H2 route is ...promising to deal with lactate producers’ over-proliferation.•The proposed approach can be applied for cheese whey, food waste, vinasse and others.•Balanced microbial equilibrium required to maintain acceptable hydrogen productivity.
Dark fermentation (DF) is one of the most promising biological methods to produce bio-hydrogen and other value added bio-products from carbohydrate-rich wastes and wastewater. However, process instability and low hydrogen production yields and rates have been highlighted as the major bottlenecks preventing further development. Numerous studies have associated such concerns with the inhibitory activity of lactate-producing bacteria (LAB) against hydrogen producers. However, an increasing number of studies have also shown lactate-based metabolic pathways as the prevailing platform for hydrogen production. This opens a vast potential to develop new strategies to deal with the “Achilles heel” of DF – LAB overgrowth – while untapping high-performance DF. This review discusses the key factors influencing the lactate-driven hydrogen production, paying particular attention to substrate composition, the operating conditions, as well as the microbiota involved in the process and its potential functionality and related biochemical routes. The current limitations and future perspectives in the field are also presented.
Head and neck cancer is the sixth leading cancer by incidence worldwide. Unfortunately, drug resistance and relapse are the principal limitations of clinical oncology for many patients, and the ...failure of conventional treatments is an extremely demoralizing experience. It is therefore crucial to find new therapeutic targets and drugs to enhance the cytotoxic effects of conventional treatments without potentiating or offsetting the adverse effects. Melatonin has oncostatic effects, although the mechanisms involved and doses required remain unclear. The purpose of this study is to determine the precise underlying mitochondrial mechanisms of melatonin, which increase the cytotoxicity of oncological treatments, and also to propose new melatonin treatments in order to alleviate and reverse radio- and chemoresistant processes. We analyzed the effects of melatonin on head and neck squamous cell carcinoma (HNSCC) cell lines (Cal-27 and SCC-9), which were treated with 0.1, 0.5, 1, and 1.5 mM melatonin combined with 8 Gy irradiation or 10 μM cisplatin. Clonogenic and MTT assays, as well as autophagy and apoptosis, involving flow cytometry and western blot, were performed in order to determine the cytotoxic effects of the treatments. Mitochondrial function was evaluated by measuring mitochondrial respiration, mtDNA content (RT-PCR), and mitochondrial mass (NAO). ROS production, antioxidant enzyme activity, and GSH/GSSG levels were analyzed using a fluorometric method. We show that high concentrations of melatonin potentiate the cytotoxic effects of radiotherapy and CDDP in HNSCC, which are associated with increased mitochondrial function in these cells. In HNSCC, melatonin induces intracellular ROS, whose accumulation plays an upstream role in mitochondria-mediated apoptosis and autophagy. Our findings indicate that melatonin, at high concentrations, combined with cisplatin and radiotherapy to improve its effectiveness, is a potential adjuvant agent.
Head and neck squamous cell carcinoma (HNSCC) clearly involves activation of the Akt mammalian target of rapamycin (mTOR) signalling pathway. However, the effectiveness of treatment with the mTOR ...inhibitor rapamycin is often limited by chemoresistance. Melatonin suppresses neoplastic growth via different mechanisms in a variety of tumours. In this study, we aimed to elucidate the effects of melatonin on rapamycin‐induced HNSCC cell death and to identify potential cross‐talk pathways. We analysed the dose‐dependent effects of melatonin in rapamycin‐treated HNSCC cell lines (Cal‐27 and SCC‐9). These cells were treated with 0.1, 0.5 or 1 mmol/L melatonin combined with 20 nM rapamycin. We further examined the potential synergistic effects of melatonin with rapamycin in Cal‐27 xenograft mice. Relationships between inhibition of the mTOR pathway, reactive oxygen species (ROS), and apoptosis and mitophagy reportedly increased the cytotoxic effects of rapamycin in HNSCC. Our results demonstrated that combined treatment with rapamycin and melatonin blocked the negative feedback loop from the specific downstream effector of mTOR activation S6K1 to Akt signalling, which decreased cell viability, proliferation and clonogenic capacity. Interestingly, combined treatment with rapamycin and melatonin‐induced changes in mitochondrial function, which were associated with increased ROS production, increasing apoptosis and mitophagy. This led to increase cell death and cellular differentiation. Our data further indicated that melatonin administration reduced rapamycin‐associated toxicity to healthy cells. Overall, our findings suggested that melatonin could be used as an adjuvant agent with rapamycin, improving effectiveness while minimizing its side effects.
Augmented Reality: Survey Mendoza-Ramírez, Carlos E.; Tudon-Martinez, Juan C.; Félix-Herrán, Luis C. ...
Applied sciences,
09/2023, Letnik:
13, Številka:
18
Journal Article
Recenzirano
Odprti dostop
An Augmented Reality (AR) system is a technology that overlays digital information, such as images, sounds, or text, onto a user’s view of the real world, providing an enriched and interactive ...experience of the surrounding environment. It has evolved into a potent instrument for improving human perception and decision-making across various domains, including industrial, automotive, healthcare, and urban planning. This systematic literature review aims to offer a comprehensive understanding of AR technology, its limitations, and implementation challenges in the most significant areas of application in engineering and beyond. The review will explore the state-of-the-art AR techniques, their potential use cases, and the barriers to widespread adoption, while also identifying future research directions and opportunities for innovation in the rapidly evolving field of augmented reality. This study works as a compilation of the existing technologies in the subject, especially useful for beginners in AR or as a starting point for developers who seek to innovate or implement new technologies, thus knowing the limitations and current challenges that could arise.
Purpose
Diagnosis and treatment of Parkinson’s Disease (PD) are typically supported by a kinematic gait analysis. Nonetheless, the main drawbacks of the classical analysis, based on a reduced set of ...markers, are the loss of small dynamical changes, the invasive methodology, and the sparse representation from few points, restricting the disease analysis. This work aims to perform a robust regional kinematic characterization, which may result in a potential digital biomarker of the disease to complement personalized analysis, treatment and monitoring of PD.
Methods
This work introduces a markerless computational framework based on a full body-segment kinematic characterization related with PD motor alterations. Firstly, a set of dense motion trajectories are computed to represent locomotion. Such trajectories are grouped using a deep learning based body segmentation, that partitions the human silhouette into regions corresponding to the head, trunk and limbs. Each resultant region is described using
dartboard
-like kinematic histograms computed along the trajectories.
Results
The proposed approach was validated using different pretrained classification models. The proposed method was evaluated on a set of 11 control subjects and 11 PD patients, achieving an average accuracy of
99.62
%
for lower-limbs and head regions.
Conclusion
This work proved to be effective to classify Parkinsonian patterns w.r.t control gaits. A major contribution of the proposed strategy is the capability to recover kinematic patterns in different body segments, particularly, for head and trunk regions, which turned out to be a decisive PD biomarker.
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