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1.
Med Biol Eng Comput ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38963467

ABSTRACT

Continuous blood pressure (BP) provides essential information for monitoring one's health condition. However, BP is currently monitored using uncomfortable cuff-based devices, which does not support continuous BP monitoring. This paper aims to introduce a blood pressure monitoring algorithm based on only photoplethysmography (PPG) signals using the deep neural network (DNN). The PPG signals are obtained from 125 unique subjects with 218 records and filtered using signal processing algorithms to reduce the effects of noise, such as baseline wandering, and motion artifacts. The proposed algorithm is based on pulse wave analysis of PPG signals, extracted various domain features from PPG signals, and mapped them to BP values. Four feature selection methods are applied and yielded four feature subsets. Therefore, an ensemble feature selection technique is proposed to obtain the optimal feature set based on major voting scores from four feature subsets. DNN models, along with the ensemble feature selection technique, outperformed in estimating the systolic blood pressure (SBP) and diastolic blood pressure (DBP) compared to previously reported approaches that rely only on the PPG signal. The coefficient of determination ( R 2 ) and mean absolute error (MAE) of the proposed algorithm are 0.962 and 2.480 mmHg, respectively, for SBP and 0.955 and 1.499 mmHg, respectively, for DBP. The proposed approach meets the Advancement of Medical Instrumentation standard for SBP and DBP estimations. Additionally, according to the British Hypertension Society standard, the results attained Grade A for both SBP and DBP estimations. It concludes that BP can be estimated more accurately using the optimal feature set and DNN models. The proposed algorithm has the potential ability to facilitate mobile healthcare devices to monitor continuous BP.

2.
SN Comput Sci ; 2(1): 18, 2021.
Article in English | MEDLINE | ID: mdl-33426530

ABSTRACT

An ongoing pandemic, the novel coronavirus disease 2019 (COVID-19) is threatening the nations of the world regardless of health infrastructure conditions. In the age of digital electronic information and telecommunication technology, scalable telehealth services are gaining immense importance by helping to maintain social distances while providing necessary healthcare services. This paper aims to review the various types of scalable telehealth services used to support patients infected by COVID-19 and other diseases during this pandemic. Recently published research papers collected from various sources such as Google Scholar, ResearchGate, PubMed, Scopus, and IEEE Xplore databases using the terms "Telehealth", "Coronavirus", "Scalable" and "COVID-19" are reviewed. The input data and relevant reports for the analysis and assessment of the various aspects of telehealth technology in the COVID-19 pandemic are taken from official websites. We described the available telehealth systems based on their communication media such as mobile networks, social media, and software based models throughout the review. A comparative analysis among the reviewed systems along with necessary challenges and possible future directions are also drawn for the proper selection of affordable technologies. The usage of scalable telehealth systems improves the quality of the healthcare system and also reduces the infection rate while keeping both patients and doctors safe during the pandemic.

3.
SN Comput Sci ; 1(5): 274, 2020.
Article in English | MEDLINE | ID: mdl-33063053

ABSTRACT

Novel coronavirus (COVID-19), an ongoing pandemic, is threatening the whole population all over the world including the nations having high or low resource health infrastructure. The number of infection as well as death cases are increasing day by day, and outperforming all the records of previously found infectious diseases. This pandemic is imposing specific pressures on the medical system almost the whole globe. The respiration problem is the main complication that a COVID-19 infected patient faced generally. It is a matter of hope that the recent deployment of small-scale technologies like 3D printer, microcontroller, ventilator, Continuous Positive Airway Pressure (CPAP) are mostly used to resolve the problem associated with medical equipment's for breathing. This paper aims to overview the existing technologies which are frequently used to support the infected patients for respiration. We described the most recent developed breathing aid devices such as oxygen therapy devices, ventilator, and CPAP throughout the review. A comparative analysis among the developed devices with necessary challenges and possible future directions are also outlined for the proper selection of affordable technologies. It is expected that this paper would be of great help to the experts who would like to contribute in this area.

4.
J Clin Invest ; 79(5): 1330-7, 1987 May.
Article in English | MEDLINE | ID: mdl-3033021

ABSTRACT

We have studied the structure and function of the insulin receptors in obese patients with and without noninsulin dependent diabetes mellitus (NIDDM) and in nonobese controls using partially purified receptors from muscle biopsies. Insulin binding was decreased in obesity due to reduced number of binding sites but no differences were observed in insulin binding between obese subjects with or without NIDDM. The structural characteristics of the receptors, as determined by affinity labeling methods and electrophoretic mobility of the beta-subunit, were not altered in obese or NIDDM compared to normal weight subjects. Furthermore, the ability of insulin to stimulate the autophosphorylation of the beta-subunit and the phosphoamino acid composition of the phosphorylated receptor were the same in all groups. However, insulin receptor kinase activity was decreased in obesity using Glu4:Tyr1 as exogenous phosphoacceptor without any appreciable additional defect when obesity was associated with NIDDM. Thus, our data are supportive of the hypothesis that in muscle of obese humans, insulin resistance is partially due to decreased insulin receptors and insulin receptor kinase activity. In NIDDM the defect(s) in muscle is probably distal to the insulin receptor kinase.


Subject(s)
Diabetes Mellitus, Type 2/enzymology , Diabetes Mellitus/enzymology , Muscles/enzymology , Obesity/enzymology , Protein-Tyrosine Kinases/metabolism , Adult , Female , Humans , Insulin/metabolism , Insulin Resistance , Male , Phosphorylation , Receptor, Insulin
5.
Biochem Biophys Res Commun ; 151(1): 123-9, 1988 Feb 29.
Article in English | MEDLINE | ID: mdl-3279949

ABSTRACT

We have studied the structure and function of the human insulin receptor in liver, skeletal muscle and adipose tissue. The alpha-subunit of the insulin receptor for liver, muscle and adipose tissue migrated on SDS-PAGE with Mrs 137632 +/- 216, 134034 +/- 1080, and 133575 +/- 165, respectively (p less than 0.05). Treatment of these receptors with neuraminidase decreased their molecule sizes and eliminated the relative size differences between the receptors. Three monoclonal antibodies (5A1, 10D9, and 20H3), directed towards different epitopes of the human insulin receptor alpha-subunit were used to probe immunological differences among the receptors. Antibodies 5A1 and 20H3 recognized all the receptors, whereas 10D9 recognized muscle and adipose tissue receptors but not liver receptors. The mobility of insulin receptor beta-subunit in the absence of insulin was the same in all tissues with a similar phosphorylation-induced decrease in mobility in SDS-PAGE in the presence of insulin. However, insulin stimulated autophosphorylation per receptor was different being greatest (p less than 0.05) in muscle (334 +/- 104 32P cpm) and similar in adipose tissue (114 +/- 10) and liver (183 +/- 68). These studies indicate, therefore, that the human insulin receptor is heterogeneous among the major target tissues for insulin, and raise the possibility that this heterogeneity may account for tissues' specific differences in insulin's biological messages.


Subject(s)
Adipose Tissue/analysis , Liver/analysis , Muscles/analysis , Receptor, Insulin/analysis , Adipose Tissue/metabolism , Antibodies, Monoclonal/immunology , Autoradiography , Electrophoresis, Polyacrylamide Gel , Humans , Immunoassay , Insulin/metabolism , Liver/metabolism , Molecular Weight , Muscles/metabolism , Receptor, Insulin/immunology , Receptor, Insulin/metabolism , Regression Analysis
6.
Biochem Biophys Res Commun ; 149(3): 1008-16, 1987 Dec 31.
Article in English | MEDLINE | ID: mdl-3322283

ABSTRACT

The present work discloses a procedure for preparation of human liver plasma membranes containing catalytically competent insulin receptor kinase. In addition to insulin promoted phosphorylation of the beta-subunit of insulin receptor kinase, insulin promoted phosphorylation of pp 120 and two other new proteins was demonstrated. The new proteins with molecular weights of 50,000 and 120,000 do not bind to WGA, pp 120 antibody or insulin receptor antibody, but bind to the antiphosphotyrosyl antibody. The identity and physiological significance of these putative substrates for insulin receptor kinase remains to be established.


Subject(s)
Cell Membrane/drug effects , Insulin/pharmacology , Membrane Proteins/isolation & purification , Phosphoproteins/isolation & purification , Protein-Tyrosine Kinases/metabolism , Receptor, Insulin/metabolism , Cell Membrane/metabolism , Diabetes Mellitus, Type 2/metabolism , Enzyme Activation/drug effects , Humans , Membrane Proteins/metabolism , Obesity/metabolism , Phosphoproteins/metabolism , Phosphorylation
7.
J Biol Chem ; 268(24): 18062-9, 1993 Aug 25.
Article in English | MEDLINE | ID: mdl-8349684

ABSTRACT

Interleukin-1 beta-converting enzyme (ICE) was purified from dialyzed cytoplasmic extracts of THP.1 human monocytic cells by a combination of DEAE-5PW and SP-5PW ion exchange and C4 reverse phase high performance liquid chromatography. Sequence information from tryptic and Asp.N peptides on the isolated 20-kDa (p20) and a 10-kDa (p10) proteins enabled the subsequent cloning of ICE (Thornberry, N. A., Bull, H. G., Calaycay, J. R., Chapman, K. T., Howard, A. D., Kostura, M. J., Miller, D. K., Molineaux, S. M., Weidner, J. R., Aunins, J., Elliston, K. O., Ayala, J. M., Casano, F. J., Chin, J., Ding, G. J.-F., Egger, L. A., Gaffney, E. P., Limjuco, G., Palyha, O. C., Raju, S. M., Rolando, A. M., Salley, J. P., Yamin, T.-T., Lee, T. D., Shively, J. E., MacCross, M., Mumford, R. A., Schmidt, J. A., and Tocci, M. J. (1992) Nature 356, 768-774) and localized the active site Cys. Immunoblots with ICE specific antibodies and NH2-terminal sequencing indicated that ICE active column fractions contained in addition to p20 and p10 an alternatively processed form of the p20 protein (p22) containing an extra 16 amino acids NH2-terminal to the p20. Furthermore, immunoblot analysis of the ion exchange column effluent showed that p20 and p22 were found together in three separate fractions distinguished by differences in p10: an intact p10 with complete ICE activity, a COOH-terminally truncated form of p10 with decreased ICE activity, and an absence of p10 with no ICE activity. These results indicate that the p10 protein is essential for ICE activity and that the ICE holoenzyme contains an intact p10 subunit paired with a p20 or p22 catalytic subunit.


Subject(s)
Metalloendopeptidases/isolation & purification , Metalloendopeptidases/metabolism , Amino Acid Sequence , Antibodies , Caspase 1 , Cell Line , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Cytoplasm/enzymology , Electrophoresis, Polyacrylamide Gel , Endopeptidases , Humans , Immunoblotting , Methionine/metabolism , Molecular Sequence Data , Monocytes , Peptide Fragments/isolation & purification , Sequence Homology, Amino Acid , Substrate Specificity
8.
J Biol Chem ; 271(45): 28212-9, 1996 Nov 08.
Article in English | MEDLINE | ID: mdl-8910438

ABSTRACT

Recombinant human inducible nitric-oxide synthase (rH-iNOS) was expressed in the baculovirus system and purified by a novel immunoaffinity column. rH-iNOS and its native counterpart from cytokine-stimulated primary hepatocytes exhibited similar molecular mass of 130 kDa on SDS-polyacrylamide gel electrophoresis, recognition by antipeptide antibodies, specific activities, and IC50 values for inhibitors. The active dimeric form exhibited a specific activity range of 114-260 nmol/min/mg at 37 degrees C and contained 1.15 +/- 0.04 mol of calmodulin/monomer. The enzyme exhibited a Soret lambdamax at 396 nm with a shoulder at 460 nm and contained 0. 28-0.64 mol of heme/monomer. Dithionite reduction under CO yielded an absorbance maximum at 446 nm, indicating a P450-type heme. Imidazole induced a type II difference spectrum, reversible by L-Arg. 2-Amino-5,6-dihydro-4H-1,3-thiazine (ADT) was competitive versus L-Arg (Ki = 22.6 +/- 1.9 nM), reversed the type II difference spectrum induced by imidazole (Kd = 17.7 nM), and altered the CO-ferrous absorbance of rH-iNOS. L-Arg did not perturb the CO-ferrous adduct directly, but it partially reversed the ADT-induced absorbance shift, indicating that both bind similarly to the protein but interact differently with the heme.


Subject(s)
Nitric Oxide Synthase/metabolism , Radiation-Protective Agents/pharmacology , Thiazines/pharmacology , Chromatography, High Pressure Liquid , Enzyme Induction , Humans , Kinetics , NADP/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
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