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1.
BMC Med Inform Decis Mak ; 24(1): 240, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223530

RESUMO

The healthcare industry has been put to test the need to manage enormous amounts of data provided by various sources, which are renowned for providing enormous quantities of heterogeneous information. The data are collected and analyzed with different Data Analytic (DA) and machine learning algorithm approaches. Researchers, scientists, and industrialists must manage or select the best approach associated with DA in healthcare. This scientific study is based on decision analysis between the DA factors and alternatives. The information affects the whole system in a rational manner. This information is very important in healthcare sector for appropriate prediction and analysis. The evaluation discusses its benefits and presents an analytic framework. The Fuzzy Analytic Hierarchy Process (Fuzzy AHP) approach is used to address the weight of the factors. The Fuzzy Techniques for Order Preference by Similarity to Ideal Solution (Fuzzy TOPSIS) address the rank of the data analytic alternatives used in healthcare sector. The models used in the article briefly discuss the challenges of DA and approaches to address those challenges. The assorted factors of DA are capture, cleaning, storage, security, stewardship, reporting, visualization, updating, sharing, and querying. The DA alternatives include descriptive, diagnostic, predictive, prescriptive, discovery, regression, cohort and inferential analyses. The most influential factors of the DA and the most suitable approach for the DA are evaluated. The 'cleaning' factor has the highest weight, and 'updating' is achieved at least by the Fuzzy-AHP approach. The regression approach of data analysis had the highest rank, and the diagnostic analysis had the lowest rank. Decision analyses are necessary for data scientists and medical providers to predict diseases appropriately in the healthcare domain. This analysis also revealed the cost benefits to hospitals.


Assuntos
Lógica Fuzzy , Humanos , Ciência de Dados , Atenção à Saúde
2.
JCI Insight ; 6(9)2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33986190

RESUMO

White adipose tissue not only serves as a reservoir for energy storage but also secretes a variety of hormonal signals and modulates systemic metabolism. A substantial amount of adipose tissue develops in early postnatal life, providing exceptional access to the formation of this important tissue. Although a number of factors have been identified that can modulate the differentiation of progenitor cells into mature adipocytes in cell-autonomous assays, it remains unclear which are connected to physiological extracellular inputs and are most relevant to tissue formation in vivo. Here, we elucidate that mature adipocytes themselves signal to adipose depot-resident progenitor cells to direct depot formation in early postnatal life and gate adipogenesis when the tissue matures. Our studies revealed that as the adipose depot matures, a signal generated in mature adipocytes is produced, converges on progenitor cells to regulate the cytoskeletal protein MYH9, and attenuates the rate of adipogenesis in vivo.


Assuntos
Proteína ADAMTS1/genética , Adipócitos/metabolismo , Adipogenia/genética , Tecido Adiposo Branco/metabolismo , Homeostase/genética , Cadeias Pesadas de Miosina/genética , Células-Tronco/metabolismo , Proteína ADAMTS1/metabolismo , Tecido Adiposo/metabolismo , Animais , Masculino , Camundongos , Camundongos Transgênicos , Cadeias Pesadas de Miosina/metabolismo
3.
ACS Appl Mater Interfaces ; 13(15): 17300-17315, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33830736

RESUMO

A technology for systemic and repeated administration of osteogenic factors for orthopedic use is an unmet medical need. Lactoferrin (∼80 kDa), present in milk, is known to support bone growth. We discovered a lactoferrin-mimetic peptide, LP2 (an 18-residue fragment from the N-terminus of the N-lobe of human lactoferrin), which self-assembles into a nano-globular assembly with a ß-sheet structure in an aqueous environment. LP2 is non-hemolytic and non-cytotoxic against human red blood cells and 3T3 fibroblasts, respectively, and appreciably stable in the human serum. LP2 through the bone morphogenetic protein-dependent mechanism stimulates osteoblast differentiation more potently than the full-length protein as well as the osteoblastic production of osteoprotegerin (an anti-osteoclastogenic factor). Consequently, daily subcutaneous administration of LP2 to rats and rabbits with osteotomy resulted in faster bone healing and stimulated bone formation in rats with a low bone mass more potently than that with teriparatide, the standard-of-care osteogenic peptide for osteoporosis. LP2 has skeletal bioavailability and is safe at the 15× osteogenic dose. Thus, LP2 is a novel peptide that can be administered systemically for the medical management of hard-to-heal fractures.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Lactoferrina/química , Nanoestruturas/química , Procedimentos Ortopédicos , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Células 3T3 , Animais , Disponibilidade Biológica , Diferenciação Celular/efeitos dos fármacos , Estabilidade de Medicamentos , Humanos , Camundongos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Fragmentos de Peptídeos/efeitos adversos , Fragmentos de Peptídeos/farmacocinética , Segurança
4.
Sensors (Basel) ; 20(22)2020 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-33266453

RESUMO

The article presents a throughput maximization approach for UAV assisted ground networks. Throughput maximization involves minimizing delay and packet loss through UAV trajectory optimization, reinforcing the congested nodes and transmission channels. The aggressive reinforcement policy is achieved by characterizing nodes, links, and overall topology through delay, loss, throughput, and distance. A position-aware graph neural network (GNN) is used for characterization, prediction, and dynamic UAV trajectory enhancement. To establish correctness, the proposed approach is validated against optimized link state routing (OLSR) driven UAV assisted ground networks. The proposed approach considerably outperforms the classical approach by demonstrating significant gains in throughput and packet delivery ratio with notable decrements in delay and packet loss. The performance analysis of the proposed approach against software-defined UAVs (U-S) and UAVs as base stations (U-B) verifies the consistency and gains in average throughput while minimizing delay and packet loss. The scalability test of the proposed approach is performed by varying data rates and the number of UAVs.

5.
ACS Chem Biol ; 15(6): 1381-1391, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32255605

RESUMO

The complexity of glucocorticoid receptor (GR) signaling cannot be measured with direct tissue analysis in living subjects, which has stifled our understanding of GR's role in human physiology or disease and impeded the development of selective GR modulators. Herein, we report 18F-5-(4-fluorobenzyl)-10-methoxy-2,2,4-trimethyl-2,5-dihydro-1H-chromeno[3,4-f]quinoline (18F-YJH08), a radioligand that enables noninvasive measurements of tissue autonomous GR expression levels in vivo with positron emission tomography (PET). YJH08 potently binds GR (Ki ∼ 0.4 nM) with ∼100-fold selectivity compared to nuclear hormone receptors in the same subfamily. 18F-YJH08 was prepared via Cu(OTf)2(py)4-mediated radiofluorination of an arylboronic acid pinacol ester with ∼12% decay corrected radiochemical yield from the starting 18F-fluoride ion. We applied treatment with the tissue-wide GR agonist dexamethasone and adrenalectomy and generated an adipocyte specific GR knockout mouse to show that 18F-YJH08 specifically binds GR in normal mouse tissues, including those for which aberrant GR expression is thought to drive severe diseases (e.g., brain, adipose tissue, kidneys). Remarkably, 18F-YJH08 PET also revealed that JG231, a potent and bioavailable HSP70 inhibitor, selectively degrades GR only in the adipose tissue of mice, a finding that foreshadows how GR targeted PET might be integrated into drug discovery to screen for selective GR modulation at the tissue level, beyond the historical screening that was performed at the transcriptional level. In summary, 18F-YJH08 enables a quantitative assessment of GR expression levels in real time among multiple tissues simultaneously, and this technology is a first step toward unraveling the daunting complexity of GR signaling and rationally engineering tissue specific therapeutic modulators in vivo.


Assuntos
Radioisótopos de Flúor/química , Tomografia por Emissão de Pósitrons/métodos , Quinolinas/química , Receptores de Glucocorticoides/análise , Animais , Dexametasona/farmacologia , Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Glucocorticoides/agonistas , Receptores de Glucocorticoides/genética
6.
J Biol Chem ; 293(51): 19874-19885, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30385503

RESUMO

Vaccination is devised/formulated to stimulate specific and prolonged immune responses for long-term protection against infection or disease. A vaccine component, namely adjuvant, enhances antigen recognition by the host immune system and thereby stimulates its cellular and adaptive responses. Especially synthetic Toll-like receptor (TLR) agonists having self-assembling properties are considered as good candidates for adjuvant development. Here, a human TLR4-derived 20-residue peptide (TR-433), present in the dimerization interface of the TLR4-myeloid differentiation protein-2 (MD2) complex, displayed self-assembly and adopted a nanostructure. Both in vitro studies and in vivo experiments in mice indicated that TR-433 is nontoxic. TR-433 induced pro-inflammatory responses in THP-1 monocytes and HEK293T cells that were transiently transfected with TLR4/CD14/MD2 and also in BALB/c mice. In light of the self-assembly and pro-inflammatory properties of TR-433, we immunized with a mixture of TR-433 and either ovalbumin or filarial antigen trehalose-6-phosphate phosphatase (TPP). A significant amount of IgG titers was produced, suggesting adjuvanting capability of TR-433 that was comparable with that of Freund's complete adjuvant (FCA) and appreciably higher than that of alum. We found that TR-433 preferentially activates type 1 helper T cell (Th1) response rather than type 2 helper T cell (Th2) response. To our knowledge, this is the first report on the identification of a short TLR4-derived peptide that possesses both self-assembling and pro-inflammatory properties and has significant efficacy as an adjuvant, capable of activating cellular responses in mice. These results indicate that TR-433 possesses significant potential for development as a new adjuvant in therapeutic application.


Assuntos
Adjuvantes Imunológicos/química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Multimerização Proteica , Receptor 4 Toll-Like/química , Vacinas/química , Vacinas/imunologia , Sequência de Aminoácidos , Animais , Brugia Malayi/imunologia , Linhagem Celular , Humanos , Imunização , Antígeno 96 de Linfócito/química , Camundongos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ovalbumina/imunologia , Estrutura Quaternária de Proteína
7.
J Biol Chem ; 293(35): 13509-13523, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-29991592

RESUMO

Adiponectin is a fat tissue-derived adipokine with beneficial effects against diabetes, cardiovascular diseases, and cancer. Accordingly, adiponectin-mimetic molecules possess significant pharmacological potential. Oligomeric states of adiponectin appear to determine its biological activity. We identified a highly conserved, 13-residue segment (ADP-1) from adiponectin's collagen domain, which comprises GXXG motifs and has one asparagine and two histidine residues that assist in oligomeric protein assembly. We therefore hypothesized that ADP-1 promotes oligomeric assembly and thereby mediates potential metabolic effects. We observed here that ADP-1 is stable in human serum and oligomerizes in aqueous environments. We also found that ADP-1 activates AMP-activated protein kinase (AMPK) in an adaptor protein, phosphotyrosine interacting with PH domain and leucine zipper 1 (APPL1)-dependent pathway and stimulates glucose uptake in rat skeletal muscle cells (L6 myotubes). ADP-1-induced glucose transport coincided with ADP-1-induced biosynthesis of glucose transporter 4 and its translocation to the plasma membrane. ADP-1 induced an interaction between APPL1 and the small GTPase Rab5, resulting in AMPK phosphorylation, in turn leading to phosphorylation of p38 mitogen-activated protein kinase (MAPK), acetyl-CoA carboxylase, and peroxisome proliferator-activated receptor α. Similar to adiponectin, ADP-1 increased the expression of the adiponectin receptor 1 (AdipoR1) gene. Of note, ADP-1 decreased blood glucose levels and enhanced insulin production in pancreatic ß cells in db/db mice. Further, ADP-1 beneficially affected lipid metabolism by enhancing lipid globule formation in mouse 3T3-L1 adipocytes. To our knowledge, this is the first report on identification of a short peptide from adiponectin with positive effects on glucose or fatty acid metabolism.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adiponectina/metabolismo , Ácidos Graxos/metabolismo , Glucose/metabolismo , Peptídeos/metabolismo , Transdução de Sinais , Células 3T3-L1 , Adiponectina/química , Adiponectina/farmacologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Células Cultivadas , Colágeno/química , Colágeno/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Hipoglicemiantes/química , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Camundongos , Peptídeos/química , Peptídeos/farmacologia , Domínios Proteicos , Ratos , Alinhamento de Sequência , Transdução de Sinais/efeitos dos fármacos
8.
Acta Biomater ; 57: 170-186, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28483698

RESUMO

Introducing cell-selectivity in antimicrobial peptides (AMPs) without compromising the antimicrobial and anti-endotoxin properties is a crucial step towards the development of new antimicrobial agents. A peptide designed on phenylalanine heptad repeat possesses significant cytotoxicity along with desired antimicrobial and anti-endotoxin properties. Amino acid substitutions at 'a' and/or 'd' positions of heptad repeats of AMPs could alter their helical structure in mammalian membrane-mimetic environments and cytotoxicity towards mammalian cells. Since proline is a helix breaker, effects of selective proline substitution(s) at 'a' and/or 'd' positions of a 15-residue peptide designed on phenylalanine heptad repeat (FR-15) were investigated. Proline-substituted FR-15 variants were highly selective toward bacteria and fungi over hRBCs and murine 3T3 cells and also retained their antibacterial activities at high salt, serum and elevated temperatures. These non-cytotoxic variants also inhibited LPS-induced production of pro-inflammatory cytokines/chemokines in human monocytes, THP-1, RAW 264.7 and in BALB/c mice. The two non-cytotoxic variants (FR8P and FR11P) showed potent anti-cancer activity against highly metastatic human breast cancer cell line MDA-MB-231 with IC50 values less than 10µM. At sub-IC50 concentrations, FR8P and FR11P also showed anti-migratory and anti-invasive effects against MDA-MB-231 cells. FR8P and FR11P induced cellular apoptosis by triggering intrinsic apoptotic pathway through depolarization of mitochondrial membrane potential and activation of caspases. Overall the results demonstrated the utilization of selective phenylalanine to proline substitution in a heptad repeat of phenylalanine residues for the design of cell-selective, broad-spectrum AMPs with significant anti-cancer properties. STATEMENT OF SIGNIFICANCE: We have demonstrated a methodology to design cell-selective potent antimicrobial and anti-endotoxin peptides by utilizing phenylalanine zipper as a template and replacement of phenylalanine residue(s) from "a" and/or "d" position(s) with proline residue(s) produced non-cytotoxic AMPs with improved antibacterial properties against the drug-resistant strains of bacteria. The work showed that the 'a' and 'd' positions of the phenylalanine heptad repeat could be replaced by an appropriate amino acid to control cytotoxicity of the peptide without compromising its potency in antimicrobial and anti-endotoxin properties. The direct bacterial membrane targeting mechanism of proline substituted analogs of parent peptide makes difficult for bacteria to grow resistance against them. The peptides designed could be lead molecules in the area of sepsis as they possess significant anti-LPS activities for in vitro and in vivo. Interestingly since cancer cells and bacterial cell membranes possess the structural resemblances, the cancer cells are also targets for these peptides making them lead molecules in this field. However, unlike in bacteria where the peptides showed membrane permeabilization property to lyse them, the peptides induced apoptosis in MDA-MB-231 breast cancer cells to inhibit their proliferation and growth. The results are significant because it reveals that "a" and "d" positions of a phenylalanine zipper can be utilized as switches to design cell-selective, antimicrobial, anti-endotoxin and anticancer peptides.


Assuntos
Substituição de Aminoácidos , Antibacterianos , Peptídeos Catiônicos Antimicrobianos , Antineoplásicos , Neoplasias da Mama/tratamento farmacológico , Escherichia coli/crescimento & desenvolvimento , Células 3T3 , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Camundongos , Fenilalanina/química , Fenilalanina/genética , Prolina/química , Prolina/genética , Células RAW 264.7 , Sequências Repetitivas de Aminoácidos , Células THP-1
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