233 research outputs found
Measurement of lipid peroxidation in biology models using gas-chromatography-aass spectrometry
C2C12 mouse myoblast cells, grown in glass vials, were connected to a cryofocusing unit to trap volatile organic compounds (VOCs). The VOCs were eluted from the trap by capacitive discharge into a gas chromatograph with time-of-flight mass spectral capabilities (GC-TOFMS) and were found to include the lipid peroxidation product hexanal. The pro-oxidant cumene hydroperoxide elevated the levels of these lipid peroxidation products, whereas the anti-oxidant butylated hydroxy toluene (BHT) impaired their production. Derivatization of the aldehyde products of lipid peroxidation in the same myoblast cells with pentafluorobenzyl hydroxylamine hydrochloride (PFB) provided evidence for formation of non-volatile products of lipid peroxidation such as malondialdehyde and 4hydroxynonenal.
Similar experiments with the human tracheal epithelial cells, 9-HTE cells treated with Haemophilus influenza bacteria, showed elevated levels of malondialdehyde at 8- hour incubation time intervals giving the initial evidence that the products of lipid peroxidation are formed long before the COX-1 enzyme is activated
Genetic predisposition to chikungunya – a blood group study in chikungunya affected families
Chikungunya fever is a viral disease transmitted to humans by the bite of CHIKV virus infected Aedes mosquitoes. During monsoon outbreak of chikungunya fever, we carried out the genetic predisposition to chikungunya in disease affected 100 families by doing blood group (ABO) tests by focusing on individuals who were likely to have a risk of chikungunya and identified the blood group involved in susceptibility/resistance to chikungunya. In the present study, based on blood group antigens, the individuals were kept in four groups – A (108), B (98), AB (20) and O (243). The result obtained was showed all Rh positive blood group individuals are susceptible to chikungunya fever. Among ABO group, the blood group O +ve individuals are more susceptible to chikungunya than other blood groups. No blood group with Rh negative was affected with chikungunya, it indicates Rh -ve more resistance to chikungunya
Mitophagy and the therapeutic clearance of damaged mitochondria for neuroprotection
Mitochondria are the foremost producers of the cellular energy currency ATP. They are also a significant source of reactive oxygen species and an important buffer of intracellular calcium. Mitochondrial retrograde signals regulate energy homeostasis and pro-survival elements whereas anterograde stimuli can trigger programmed cell death. Maintenance of a healthy, functional mitochondria network is therefore essential, and several mechanisms of mitochondrial quality control have been described. Mitochondrial dysfunction is linked to several neurodegenerative conditions including Parkinson, and Huntingdon diseases as well as Amyotrophic lateral sclerosis. Understanding the mechanisms governing mitochondrial quality control may reveal novel strategies for pharmacological intervention and disease therapy
Functional phosphatome requirement for protein homeostasis, networked mitochondria, and sarcomere structure in C. elegans muscle
Background: Skeletal muscle is central to locomotion and metabolic homeostasis. The laboratory worm C. elegans has been developed into a genomic model for assessing the genes and signals that regulate muscle development and protein degradation. Past work has identified a receptor tyrosine kinase signalling network that combinatorially controls autophagy, nerve signal to muscle to oppose proteasome based degradation, and extracellular matrix based signals that control calpain and caspase activation. The last two discoveries were enabled by following up results from a functional genomic screen of known regulators of muscle. Recently, a screen of the kinome requirement for muscle homeostasis identified roughly 40% of kinases as required for C. elegans muscle health; 80 have identified human orthologues and 53 are known to be expressed in skeletal muscle. To complement this kinome screen, here we screen most of the phosphatases in C. elegans.
Methods: RNAi was used to knockdown phosphatase encoding genes. Knockdown was first conducted during development with positive results also knocked down only in fully developed adult muscle. Protein homeostasis, mitochondrial structure, and sarcomere structure were assessed using transgenic reporter proteins. Genes identified as being required to prevent protein degradation were also knocked down in conditions that blocked proteasome or autophagic degradation. Genes identified as being required to prevent autophagic degradation were also assessed for autophagic vesicle accumulation using another transgenic reporter. Lastly, bioinformatics were used to look for overlap between kinases and phosphatases required for muscle homeostasis and the prediction that one phosphatase was required to prevent MAPK activation was assessed by Western blot.
Results: A little over half of all phosphatases are each required to prevent abnormal development or maintenance of muscle. 86 of these phosphatase have known human orthologues, 57 of which are known to be expressed in human skeletal muscle. Of the phosphatases required to prevent abnormal muscle protein degradation, roughly half are required to prevent increased autophagy.
Conclusions: A significant portion of both the kinome and phosphatome are required for establishing and maintaining C. elegans muscle health. Autophagy appears to be the mostly commonly triggered form of protein degradation in response to disruption of phosphorylation based signalling. The results from these screens provide measurable phenotypes for analysing the combined contribution of kinases and phosphatases in a multi-cellular organism and suggest new potential regulators of human skeletal muscle for further analysis
Connective tissue metabolism in chikungunya patients
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Facial Emotions and Behaviour Monitoring System using DNN
In this paper, Machine Learning Algorithms are used to implement the proposed approach to identify social distance, face masks, drowsiness detection, age-gender detection, and emotion detection. While dealing with social distancing initially, we need to detect humans’ faces, which are available by using COCO (Common Objects in Context) datasets, and later on, polygon-shaped ROI (Rectangular-region of Interest) is warped with a rectangle, which helps to find the distance from each centroid (person). Similarly, we predict the facemask, age-gender, emotion, and drowsiness altogether using frontal-face detection and eye-detection via haarcascade dataset loaded into Convolutional Neural Network (CNN) to train and test the models on colour mapped images. In the proposed model, we are using machine-learning techniques such as linear discriminant Analysis (LDA), Independent Component Analysis (ICA), Principal Component Analysis (PCA) for age-gender detection and emotion detection, K-Nearest Neighbours (KNN) for Social Distancing, and Support Vector Machine (SVM) for facemask detection and drowsiness detection. The accuracy of proposed system depends on frame (i.e., 88.2%, 89.7%, 95.1% and 98.3% in 0~0.2s, 0.2~0.6s, 0.6~1s, >1s time windows respectively). The accuracy even depends upon the distance away from the camera (i.e., 60.4%, 73.9%, 89.3%, 95.2%, and 62.2% in >15, 15~10, 10~6, 6~0.5, <0.5 meters respectively). The resultant average accuracy of all the models is 96.3%, which is capable to predict various tasks as said above. This complete model is made accessible to users via a standalone software/Desktop GUI. The proposed approach is promising for performing all the tasks and activities more accurately and efficiently.the systemic health of the patient and avoiding possible drug interaction
Genetic predisposition to chikungunya – a blood group study in chikungunya affected families
Symmorphosis through dietary regulation: a combinatorial role for proteolysis, autophagy and protein synthesis in normalising muscle metabolism and function of hypertrophic mice after acute starvation
Animals are imbued with adaptive mechanisms spanning from the tissue/organ to the cellular scale which insure that processes of homeostasis are preserved in the landscape of size change. However we and others have postulated that the degree of adaptation is limited and that once outside the normal levels of size fluctuations, cells and tissues function in an aberant manner. In this study we examine the function of muscle in the myostatin null mouse which is an excellent model for hypertrophy beyond levels of normal growth and consequeces of acute starvation to restore mass. We show that muscle growth is sustained through protein synthesis driven by Serum/Glucocorticoid Kinase 1 (SGK1) rather than Akt1. Furthermore our metabonomic profiling of hypertrophic muscle shows that carbon from nutrient sources is being channelled for the production of biomass rather than ATP production. However the muscle displays elevated levels of autophagy and decreased levels of muscle tension. We demonstrate the myostatin null muscle is acutely sensitive to changes in diet and activates both the proteolytic and autophagy programmes and shutting down protein synthesis more extensively than is the case for wild-types. Poignantly we show that acute starvation which is detrimental to wild-type animals is beneficial in terms of metabolism and muscle function in the myostatin null mice by normalising tension production
Regulation of proteasome assembly and activity in health and disease
The proteasome degrades most cellular proteins in a controlled and tightly regulated manner and thereby controls many processes, including cell cycle, transcription, signalling, trafficking and protein quality control. Proteasomal degradation is vital in all cells and organisms, and dysfunction or failure of proteasomal degradation is associated with diverse human diseases, including cancer and neurodegeneration. Target selection is an important and well-established way to control protein degradation. In addition, mounting evidence indicates that cells adjust proteasome-mediated degradation to their needs by regulating proteasome abundance through the coordinated expression of proteasome subunits and assembly chaperones. Central to the regulation of proteasome assembly is TOR complex 1 (TORC1), which is the master regulator of cell growth and stress. This Review discusses how proteasome assembly and the regulation of proteasomal degradation are integrated with cellular physiology, including the interplay between the proteasome and autophagy pathways. Understanding these mechanisms has potential implications for disease therapy, as the misregulation of proteasome function contributes to human diseases such as cancer and neurodegeneration.</p
Destructive arthritis in a patient with chikungunya virus infection with persistent specific IgM antibodies
<p>Abstract</p> <p>Background</p> <p>Chikungunya fever is an emerging arboviral disease characterized by an algo-eruptive syndrome, inflammatory polyarthralgias, or tenosynovitis that can last for months to years. Up to now, the pathophysiology of the chronic stage is poorly understood.</p> <p>Case presentation</p> <p>We report the first case of CHIKV infection with chronic associated rheumatism in a patient who developed progressive erosive arthritis with expression of inflammatory mediators and persistence of specific IgM antibodies over 24 months following infection.</p> <p>Conclusions</p> <p>Understanding the specific features of chikungunya virus as well as how the virus interacts with its host are essential for the prevention, treatment or cure of chikungunya disease.</p
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