Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 174
Filtrar
1.
Chem Rev ; 123(12): 7953-8039, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37262362

RESUMO

Whole blood, as one of the most significant biological fluids, provides critical information for health management and disease monitoring. Over the past 10 years, advances in nanotechnology, microfluidics, and biomarker research have spurred the development of powerful miniaturized diagnostic systems for whole blood testing toward the goal of disease monitoring and treatment. Among the techniques employed for whole-blood diagnostics, electrochemical biosensors, as known to be rapid, sensitive, capable of miniaturization, reagentless and washing free, become a class of emerging technology to achieve the target detection specifically and directly in complex media, e.g., whole blood or even in the living body. Here we are aiming to provide a comprehensive review to summarize advances over the past decade in the development of electrochemical sensors for whole blood analysis. Further, we address the remaining challenges and opportunities to integrate electrochemical sensing platforms.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Nanotecnologia/métodos , Biomarcadores , Microfluídica
2.
Can J Anaesth ; 71(6): 849-869, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38418761

RESUMO

PURPOSE: Nearly all patients with hip fractures undergo surgical treatment. The use of different anesthesia techniques during surgery may influence the clinical outcomes. The optimal anesthetic technique for patients undergoing hip fracture surgery is still controversial. We performed this updated systematic review and meta-analysis to compare clinical outcomes of patients undergoing hip fracture surgery with different anesthesia techniques. SOURCE: Articles published from 2000 to May 2023 were included from MEDLINE, Embase, Web of Science, and the Cochrane Library. We included randomized controlled trials and observational studies comparing general anesthesia (GA) with regional anesthesia (RA) for the outcomes of 30-day mortality, 90-day mortality, in-hospital mortality, perioperative complications, length of hospital stay, and length of surgery in patients undergoing hip fracture surgery. Subgroup analyses were performed for the outcomes based on study design (randomized controlled trials or observational studies). We used a random-effects model for all analyses. PRINCIPAL FINDINGS: In this meta-analysis, we included 12 randomized controlled trials. There was no difference in postoperative 30-day mortality between the two groups (odds ratio [OR], 0.88; 95% confidence interval [CI], 0.44 to 1.74; I2 = 0%). The incidence of intraoperative hypotension was lower in patients who received RA vs GA (OR, 0.52; 95% CI, 0.38 to 0.72; I2 = 0%). No significant differences were observed in 90-day mortality, in-hospital mortality, postoperative delirium, pneumonia, myocardial infarction, venous thromboembolism, length of surgery, and length of hospital stay. CONCLUSION: In this updated systematic review and meta-analysis, RA did not reduce postoperative 30-day mortality in hip fracture surgery patients compared to GA. Fewer patients receiving RA had intraoperative hypotension than those receiving GA did. Apart from intraoperative hypotension, the data showed no differences in complications between the two anesthetic techniques. STUDY REGISTRATION: PROSPERO (CRD42023411854); registered 7 April 2023.


RéSUMé: OBJECTIF: Presque toutes les personnes ayant subi une fracture de la hanche se font opérer. L'utilisation de différentes techniques d'anesthésie pendant la chirurgie peut influencer les issues cliniques. La technique d'anesthésie optimale pour la patientèle bénéficiant de chirurgie de fracture de la hanche est encore controversée. Nous avons réalisé cette mise à jour par revue systématique et méta-analyse pour comparer les issues cliniques des personnes bénéficiant d'une chirurgie de fracture de la hanche avec différentes techniques d'anesthésie. SOURCES: Les articles publiés de 2000 à mai 2023 ont été inclus à partir des bases de données MEDLINE, Embase, Web of Science et Cochrane Library. Nous avons inclus des études randomisées contrôlées et des études observationnelles comparant l'anesthésie générale (AG) à l'anesthésie régionale (AR) pour les issues de mortalité à 30 jours, de mortalité à 90 jours, de mortalité intrahospitalière, de complications périopératoires, de durée de séjour à l'hôpital et de durée de la chirurgie pour les personnes bénéficiant d'une chirurgie de fracture de la hanche. Des analyses de sous-groupes ont été réalisées pour les issues en fonction de la méthodologie utilisée (étude randomisée contrôlée ou étude observationnelle). Un modèle à effets aléatoires a été utilisé pour toutes les analyses. CONSTATATIONS PRINCIPALES: Dans cette méta-analyse, nous avons inclus 12 études randomisées contrôlées. Il n'y avait pas de différence dans la mortalité postopératoire à 30 jours entre les deux groupes (rapport de cotes [RC], 0,88; intervalle de confiance à 95 % [IC], 0,44 à 1,74; I2 = 0 %). L'incidence d'hypotension peropératoire était plus faible chez les patient·es ayant reçu une AR vs une AG (RC, 0,52; IC 95 %, 0,38 à 0,72; I2 = 0 %). Aucune différence significative n'a été observée dans les issues de mortalité à 90 jours, de mortalité intrahospitalière, de delirium postopératoire, de pneumonie, d'infarctus du myocarde, de thromboembolie veineuse, de durée de la chirurgie, et de durée du séjour à l'hôpital. CONCLUSION: Dans cette revue systématique avec méta-analyse, l'anesthésie régionale n'a pas réduit la mortalité postopératoire à 30 jours chez les personnes ayant bénéficié d'une chirurgie de fracture de la hanche par rapport à l'anesthésie générale. Une proportion moindre de patient·es ayant reçu une AR présentaient une hypotension peropératoire par rapport aux personnes ayant reçu une AG. En dehors de l'hypotension peropératoire, les données n'ont montré aucune différence dans les complications entre les deux techniques anesthésiques. ENREGISTREMENT DE L'éTUDE: PROSPERO (CRD42023411854); enregistrée le 7 avril 2023.


Assuntos
Anestesia por Condução , Anestesia Geral , Fraturas do Quadril , Mortalidade Hospitalar , Tempo de Internação , Complicações Pós-Operatórias , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Fraturas do Quadril/cirurgia , Anestesia Geral/métodos , Anestesia por Condução/métodos , Tempo de Internação/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia
3.
Blood ; 138(1): 71-85, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-33763698

RESUMO

RNA-binding proteins (RBPs) are critical regulators of transcription and translation that are often dysregulated in cancer. Although RBPs are increasingly recognized as being important for normal hematopoiesis and for hematologic malignancies as oncogenes or tumor suppressors, RBPs that are essential for the maintenance and survival of leukemia remain elusive. Here we show that YBX1 is specifically required for maintaining myeloid leukemia cell survival in an N6-methyladenosine (m6A)-dependent manner. We found that expression of YBX1 is significantly upregulated in myeloid leukemia cells, and deletion of YBX1 dramatically induces apoptosis and promotes differentiation coupled with reduced proliferation and impaired leukemic capacity of primary human and mouse acute myeloid leukemia cells in vitro and in vivo. Loss of YBX1 has no obvious effect on normal hematopoiesis. Mechanistically, YBX1 interacts with insulin-like growth factor 2 messenger RNA (mRNA)-binding proteins (IGF2BPs) and stabilizes m6A-tagged RNA. Moreover, YBX1 deficiency dysregulates the expression of apoptosis-related genes and promotes mRNA decay of MYC and BCL2 in an m6A-dependent manner, which contributes to the defective survival that results from deletion of YBX1. Thus, our findings have uncovered a selective and critical role of YBX1 in maintaining myeloid leukemia survival, which might provide a rationale for the therapeutic targeting of YBX1 in myeloid leukemia.


Assuntos
Adenosina/análogos & derivados , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Adenosina/metabolismo , Animais , Apoptose/genética , Sobrevivência Celular/genética , Deleção de Genes , Regulação Leucêmica da Expressão Gênica , Hematopoese/genética , Humanos , Leucemia Mieloide Aguda/genética , Camundongos Endogâmicos C57BL , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Neoplásico/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteína 1 de Ligação a Y-Box/genética
4.
Analyst ; 148(13): 2965-2974, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37265393

RESUMO

A wearable sweat sensor, which could continuously monitor biomolecules related to the human physiological state, is emerging as a promising piece of health surveillance equipment. However, current sensors cannot simultaneously achieve a detection performance that equates to that of traditional sensors and satisfactory mechanical strength. Herein, a wearable sweat sensor with excellent detection performance and mechanical stability is designed and fabricated. Based on the integration of laser-induced graphene electrodes and a screen printing technique, this wearable sweat sensor could realize both the separate and simultaneous detection of uric acid (UA), tyrosine (Tyr), and ascorbic acid (AA) with high sensitivity. Good UA sensing performance in artificial sweat could be maintained even after 20 000 bends. In addition, the sensor can operate well in the wearing state or in a complex bovine whole blood sample. For the detection of human sweat, the changes in UA concentration after a purine-rich meal are continuously monitored and the results are in accordance with the corresponding serum UA detection results tested with a commercial serum UA meter. These results suggest its application potential in health monitoring for both gout patients and healthy humans.


Assuntos
Suor , Animais , Bovinos , Suor/química , Ácido Úrico/análise , Tirosina/análise , Ácido Ascórbico/análise , Humanos , Dispositivos Eletrônicos Vestíveis
5.
J Nanobiotechnology ; 21(1): 378, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848956

RESUMO

BACKGROUND: The combination of drug delivery with immune checkpoint targeting has been extensively studied in cancer therapy. However, the clinical benefit for patients from this strategy is still limited. B7 homolog 3 protein (B7-H3), also known as CD276 (B7-H3/CD276), is a promising therapeutic target for anti-cancer treatment. It is widely overexpressed on the surface of malignant cells and tumor vasculature, and its overexpression is associated with poor prognosis. Herein, we report B7H3 targeting doxorubicin (Dox)-conjugated gold nanocages (B7H3/Dox@GNCs) with pH-responsive drug release as a selective, precise, and synergistic chemotherapy-photothermal therapy agent against non-small-cell lung cancer (NSCLC). RESULTS: In vitro, B7H3/Dox@GNCs exhibited a responsive release of Dox in the tumor acidic microenvironment. We also demonstrated enhanced intracellular uptake, induced cell cycle arrest, and increased apoptosis in B7H3 overexpressing NSCLC cells. In xenograft tumor models, B7H3/Dox@GNCs exhibited tumor tissue targeting and sustained drug release in response to the acidic environment. Wherein they synchronously destroyed B7H3 positive tumor cells, tumor-associated vasculature, and stromal fibroblasts. CONCLUSION: This study presents a dual-compartment targeted B7H3 multifunctional gold conjugate system that can precisely control Dox exposure in a spatio-temporal manner without evident toxicity and suggests a general strategy for synergistic therapy against NSCLC.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Doxorrubicina , Neoplasias Pulmonares , Nanopartículas , Terapia Fototérmica , Humanos , Antígenos B7 , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Ouro , Concentração de Íons de Hidrogênio , Hipertermia Induzida , Neoplasias Pulmonares/tratamento farmacológico , Fototerapia , Terapia Fototérmica/métodos , Microambiente Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Animais , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Clin Exp Hypertens ; 45(1): 2177667, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36809885

RESUMO

BACKGROUND: Hypertensive intracerebral hemorrhage (HICH) is a life-threatening disease and lacks effective treatments. Previous studies have confirmed that metabolic profiles altered after ischemic stroke, but how brain metabolism changes after HICH was unclear. This study aimed to explore the metabolic profiles after HICH and the therapeutic effects of soyasaponin I on HICH. METHODS: HICH model was established first. Hematoxylin and eosin staining was used to estimate the pathological changes after HICH. Western blot and Evans blue extravasation assay were applied to determine the integrity of the blood-brain barrier (BBB). Enzyme-linked immunosorbent assay was used to detect the activation of the renin-angiotensin-aldosterone system (RAAS). Next, liquid chromatography-mass spectrometry-untargeted metabolomics was utilized to analyze the metabolic profiles of brain tissues after HICH. Finally, soyasaponin I was administered to HICH rats, and the severity of HICH and activation of the RAAS were further assessed. RESULTS: We successfully constructed HICH model. HICH significantly impaired BBB integrity and activated RAAS. HICH increased PE(14:0/24:1(15Z)), arachidonoyl serinol, PS(18:0/22:6(4Z, 7Z, 10Z, 13Z, 16Z, and 19Z)), PS(20:1(11Z)/20:5(5Z, 8Z, 11Z, 14Z, and 17Z)), glucose 1-phosphate, etc., in the brain, whereas decreased creatine, tripamide, D-N-(carboxyacetyl)alanine, N-acetylaspartate, N-acetylaspartylglutamic acid, and so on in the hemorrhagic hemisphere. Cerebral soyasaponin I was found to be downregulated after HICH and supplementation of soyasaponin I inactivated the RAAS and alleviated HICH. CONCLUSION: The metabolic profiles of the brains changed after HICH. Soyasaponin I alleviated HICH via inhibiting the RAAS and may serve as an effective drug for the treatment of HICH in the future.


Assuntos
Hemorragia Intracraniana Hipertensiva , Ácido Oleanólico , Saponinas , Ratos , Animais , Sistema Renina-Angiotensina
7.
Bioorg Chem ; 120: 105638, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35121550

RESUMO

Structural modification of natural products is the effective option to improve their pharmacological effects and drug properties. DLF is a lead compound of antitumor drug, which is a broad-spectrum, low toxic and high-efficient component isolated from Selaginella doederleinii Hieron by our research group. Here, we report the structural modification method of this component, and find that the acetylated product of C4'''- OH (C4'''-acetyl-delicaflavone, 4'''ADLF) has better inhibitory effect on the selected cancer cell lines, including, lung, liver, colon and cervical cancer cell lines. Since the increased water solubility of 4'''ADLF may lead to higher absorption rate and activity, we evaluate the pharmacodynamics in vitro and in vivo, and the pharmacokinetic of 4'''ADLF. It shows that 4'''ADLF inhibit the proliferation and induce cycle arrest in tumor cells, and had better anticancer activity and bioavailability than DLF.


Assuntos
Antineoplásicos , Selaginellaceae , Antineoplásicos/farmacologia , Apoptose , Disponibilidade Biológica , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Simulação de Acoplamento Molecular , Estrutura Molecular , Selaginellaceae/química , Solubilidade , Relação Estrutura-Atividade
8.
Proc Natl Acad Sci U S A ; 116(21): 10482-10487, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31068472

RESUMO

A major obstacle to curing chronic myeloid leukemia (CML) is the intrinsic resistance of CML stem cells (CMLSCs) to the drug imatinib mesylate (IM). Prosurvival genes that are preferentially expressed in CMLSCs compared with normal hematopoietic stem cells (HSCs) represent potential therapeutic targets for selectively eradicating CMLSCs. However, the discovery of such preferentially expressed genes has been hampered by the inability to completely separate CMLSCs from HSCs, which display a very similar set of surface markers. To overcome this challenge, and to minimize confounding effects of individual differences in gene expression profiles, we performed single-cell RNA-seq on CMLSCs and HSCs that were isolated from the same patient and distinguished based on the presence or absence of BCR-ABL. Among genes preferentially expressed in CMLSCs is PIM2, which encodes a prosurvival serine-threonine kinase that phosphorylates and inhibits the proapoptotic protein BAD. We show that IM resistance of CMLSCs is due, at least in part, to maintenance of BAD phosphorylation by PIM2. We find that in CMLSCs, PIM2 expression is promoted by both a BCR-ABL-dependent (IM-sensitive) STAT5-mediated pathway and a BCR-ABL-independent (IM-resistant) STAT4-mediated pathway. Combined treatment with IM and a PIM inhibitor synergistically increases apoptosis of CMLSCs, suppresses colony formation, and significantly prolongs survival in a mouse CML model, with a negligible effect on HSCs. Our results reveal a therapeutically targetable mechanism of IM resistance in CMLSCs. The experimental approach that we describe can be generally applied to other malignancies that harbor oncogenic fusion proteins or other characteristic genetic markers.


Assuntos
Compostos de Bifenilo/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Células-Tronco Neoplásicas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Tiazolidinas/uso terapêutico , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Mesilato de Imatinib , Leucemia Experimental/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Camundongos , Terapia de Alvo Molecular , Fosforilação , Inibidores de Proteínas Quinases , Fatores de Transcrição STAT/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo
9.
Molecules ; 27(13)2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35807375

RESUMO

Smoke-induced acute lung injury (ALI) is a grievous disease with high mortality. Despite advances in medical intervention, no drug has yet been approved by the Food and Drug Administration (FDA) for ALI. In this study, we reported that pretreatment with high-molecular-weight hyaluronan (1600 kDa, HA1600) alleviated pulmonary inflammation and injury in mice exposed to smoke and also upregulated long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), as well as suppressor of cytokine signaling-1 (SOCS-1), in the lung tissues. Next, we overexpressed MALAT1 in the lungs by intratracheal administration of adenovirus cloned with MALAT1 cDNA and found that the survival of mice after smoke exposure was improved. Moreover, pulmonary overexpression of MALAT1 ameliorated smoke-induced ALI in mice and elevated the level of SOCS-1 in the lungs. In conclusion, the results pointed out that HA1600 exerted a protective effect against smoke-induced ALI through increasing the MALAT1 level and the subsequent SOCS-1 expression. Our study provides a potential therapeutic approach to smoke-induced ALI and a novel insight into the mechanism of action of HA1600.


Assuntos
Lesão Pulmonar Aguda , Ácido Hialurônico , RNA Longo não Codificante , Proteína 1 Supressora da Sinalização de Citocina , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Animais , Ácido Hialurônico/farmacologia , Pulmão/patologia , Camundongos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fumaça , Proteína 1 Supressora da Sinalização de Citocina/genética , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Regulação para Cima
10.
Anal Chem ; 93(23): 8354-8361, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34061504

RESUMO

Hybridization chain reaction (HCR) amplification strategy has been extensively explored for the application of electrochemical DNA-based sensors. Despite the enhancement in its sensitivity using the HCR, such sensor platform exhibited significant sensor-to-sensor variations in current due to variations in probe counts and lengths. To circumvent this, we are developing here a calibration-free "O-N" approach to generate a ratiometric, unitless value that is independent of these variations. Specifically, this approach employs two types of redox reporters, denoted as "One reporter" and "N reporters", with the former attached on the capture DNA and the latter on H1 and H2 strands. By optimizing the attachment sites of these reporters onto DNA strands, we demonstrate a significantly enhanced sensitivity of such sensor platform by four orders of magnitude, achieving accurate, calibration-free measurement of nucleic acids including ctDNA directly in undiluted whole blood without the requirement to calibrate each individual sensor.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos , Calibragem , DNA/genética , Técnicas Eletroquímicas , Hibridização de Ácido Nucleico
11.
Anal Chem ; 93(14): 5849-5855, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33787229

RESUMO

The continuous, real-time monitoring of specific analytes in situ in biological fluids would provide personalized, high-precision pharmacokinetic information for the goal of precision medicine. Due to their conformationally linked signaling mechanism, electrochemical aptamer-based (E-AB) sensors are promising candidates for accurate measurements in such complex media. They suffer, however, from severe baseline drift when interrogated continuously and in real-time manner. In response, here, we investigate a couple of self-assembled monolayers in the application of E-AB sensors, achieving the improvement of their baseline stability and simultaneous modulation of sensor performance, e.g., target affinity and specificity.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Técnicas Eletroquímicas
12.
Mediators Inflamm ; 2021: 9954909, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34366712

RESUMO

Intervertebral disc degenerative disease (IDD) is the most common degenerative spine disease, which leads to chronic low back pain and symptoms in the lower extremities. In this study, we found that RORα, a member of the retinoid-related orphan receptor family, is significantly elevated in nucleus pulposus tissue in IDD patients. The elevation of RORα is associated with increased apoptosis of nucleus pulposus (NP) cells. Therefore, we applicated a well-established inverse agonist of RORα, SR3335, to investigate its role in regulating NP cell metabolism and apoptosis. To further investigate the mechanism that SR3335 regulates the pathogenesis of IDD in vitro, tumor necrosis factor alpha (TNF-α) stimulation was used in human NP cells to mimic the hostile environment that leads to degeneration. We found that SR3335 treatment reversed the trend of increased apoptosis in NP cells induced by TNF-α treatment. Next, TNF-α treatment upregulated the expression of type II collagen and aggrecan and downregulated MMP13 (matrix-degrading enzyme matrix metalloproteinase 13) and ADAMTS4 (a disintegrin and metalloproteinase with thrombospondin motifs 4). However, these effects were reversed after SR3335 treatment. Furthermore, we find that SR3335 mediated the effect in NP cells by regulating the YAP signaling pathway, especially by affecting the phosphorylation state of YAP. In conclusion, the reduction of matrix degradation enzymes and apoptosis upon SR3335 treatment suggests that SR3335 is a promising drug in reversing the deleterious microenvironment in IDD patients.


Assuntos
Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Núcleo Pulposo/metabolismo , Proteínas de Sinalização YAP/biossíntese , Proteína ADAMTS4/metabolismo , Idoso , Animais , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Colágeno Tipo II/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Pessoa de Meia-Idade , Simulação de Acoplamento Molecular , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Fosforilação , Ratos , Ratos Sprague-Dawley , Sulfonamidas/farmacologia , Tiofenos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
13.
Orthopade ; 50(2): 143-149, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31940055

RESUMO

OBJECTIVE: To evaluate the correlation between continuation of glucocorticoid (GC) treatment and risk of femoral head collapse in patients with glucocorticoid-induced osteonecrosis of the femoral head (GIONFH) after hip-preserving interventions. METHODS: The cohort included patients with GIONFH who had received a hip-preserving intervention between 1 January 2014 and 1 April 2016. All hips were at the non-collapse stage. The independent variable and the dependent variable were postoperative GC use and femoral head collapse (≥3 mm), respectively. Multivariate Cox proportional hazards regression were performed to estimate the association of the variables after adjusting for other covariates. RESULTS: A total of 27 hips (24 patients) were included for the final data analysis of which 6 hips out of 18 developed femoral head collapse (≥3 mm) in patients who discontinued taking GC postoperatively and 6 hips out of 9 developed collapse (≥3 mm) in those requiring GC treatment postoperatively. In the fully adjusted Cox proportional hazards model, the risk of femoral head collapse (≥3 mm) was higher in participants requiring postoperative GC use than those not requiring GC (hazard ratio, HR 3.7, 95% confidence interval, CI 1.1-13.0). CONCLUSION: The results of this study demonstrated that patients with GIONFH who continued GC treatment postoperatively had a significantly increased risk of femoral head collapse (≥3 mm) compared to those who discontinued use of GC.


Assuntos
Necrose da Cabeça do Fêmur , Glucocorticoides , Cabeça do Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/epidemiologia , Glucocorticoides/efeitos adversos , Quadril , Humanos , Estudos Retrospectivos , Resultado do Tratamento
14.
Anal Chem ; 92(19): 13427-13433, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32872766

RESUMO

Electrochemical aptamer-based (E-AB) sensors, exploiting binding-induced changes in biomolecular conformation, are rapid, specific, and selective and perform well even in a complex matrix, such as directly in whole blood and even in vivo. However, like all sensors employing biomolecular recognitions, E-AB sensors suffer from an inherent limitation of single-site binding, i.e., its fixed dose-response curve. To circumvent this, we employ here distal-site mutation and allosteric inhibition to rationally tune the dynamic range of E-AB sensors, achieving sets of sensors with a significantly varied target affinity (∼3 orders of magnitude). Using their combination, we recreate several approaches to narrow (down to 5-fold) or extend (up to 2000-fold) the dynamic range of biological receptors. The thermodynamic consequences of aptamer-surface interactions are estimated via the free-energy difference in solution-phase and surface-bound biosensors employing the same aptamer as a recognition element, revealing that an allostery strategy provides a more predictable and efficient means to finely control the target affinity and dynamic range. Such an ability to rationally modulate the affinity of biomolecule receptors would open the door to applications including cancer therapy, bioelectronics, and many other fields employing biomolecule recognition.


Assuntos
Aptâmeros de Nucleotídeos/análise , Técnicas Biossensoriais , Técnicas Eletroquímicas , Termodinâmica , Regulação Alostérica/efeitos dos fármacos , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/farmacologia , Mutação , Propriedades de Superfície
15.
Anal Chem ; 92(18): 12437-12441, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32786211

RESUMO

Electrochemical aptamer-based (E-AB) biosensors suffer from sensor-to-sensor signal variations due to the variation of the total number and the heterogeneity of probes immobilized on the electrode surface, with the former attracting more attention. As such, a calibration process to correct for such variations is required for this type of sensor, causing inconvenience and inaccessibility in harsh sensing environments such as blood samples, which has dramatically limited the widespread clinical use of biosensors. In response, here, we have adopted E-AB sensors to achieve calibration-free measurements of small biological/drug molecules. Specifically, we employ one probe-attached redox reporter and a second intercalated redox reporter to generate two signals, achieving good sensor-to-sensor reproducibility and thus obviating the need for calibration. We first demonstrated the capability of E-AB sensors for the accurate measurement of kanamycin, tobramycin, and adenosine triphosphate (ATP) in phosphate-buffered saline (PBS) buffer, achieving concentration ranges of approximately 4.7 × 103-, 2.0 × 103-, and 12.7-fold, respectively. Then, we applied this calibration-free approach to the measurement of these three target molecules directly in undiluted serum, achieving a concentration precision of a few micromolars.


Assuntos
Trifosfato de Adenosina/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Técnicas Eletroquímicas , Canamicina/análise , Tobramicina/análise , Calibragem , Oxirredução
16.
Blood ; 130(5): 655-665, 2017 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-28576876

RESUMO

Chronic myeloid leukemia (CML) is a hematopoietic stem cell (HSC)-driven neoplasia characterized by expression of the constitutively active tyrosine kinase BCR/Abl. CML therapy based on tyrosine kinase inhibitors (TKIs) is highly effective in inducing remission but not in targeting leukemia stem cells (LSCs), which sustain minimal residual disease and are responsible for CML relapse following discontinuation of treatment. The identification of molecules capable of targeting LSCs appears therefore of primary importance to aim at CML eradication. LSCs home in bone marrow areas at low oxygen tension, where HSCs are physiologically hosted. This study addresses the effects of pharmacological inhibition of hypoxia-inducible factor-1 (HIF-1), a critical regulator of LSC survival, on the maintenance of CML stem cell potential. We found that the HIF-1 inhibitor acriflavine (ACF) decreased survival and growth of CML cells. These effects were paralleled by decreased expression of c-Myc and stemness-related genes. Using different in vitro stem cell assays, we showed that ACF, but not TKIs, targets the stem cell potential of CML cells, including primary cells explanted from 12 CML patients. Moreover, in a murine CML model, ACF decreased leukemia development and reduced LSC maintenance. Importantly, ACF exhibited significantly less-severe effects on non-CML hematopoietic cells in vitro and in vivo. Thus, we propose ACF, a US Food and Drug Administration (FDA)-approved drug for nononcological use in humans, as a novel therapeutic approach to prevent CML relapse and, in combination with TKIs, enhance induction of remission.


Assuntos
Acriflavina/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias Experimentais , Células-Tronco Neoplásicas/metabolismo , Animais , Sobrevivência Celular , Humanos , Fator 1 Induzível por Hipóxia/metabolismo , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Camundongos , Células NIH 3T3 , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Células-Tronco Neoplásicas/patologia
17.
Adv Exp Med Biol ; 1143: 191-215, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31338821

RESUMO

Chronic myeloid leukemia (CML) is a clonal myeloproliferative disorder characterized by a chromosome translocation that generates the BCR-ABL oncogene encoding a constitutively activated tyrosine kinase. Although BCR-ABL tyrosine kinase inhibitors (TKIs) are highly effective in treating CML at chronic phase, a number of patients develop drug resistance due to the inability of TKIs to kill leukemia stem cells (LSCs). Similar to other types of hematopoietic malignancies, LSCs in CML are believed to be a rare cell population responsible for leukemia initiation, disease progression, and drug resistance. Therefore, a full understanding of the biology of LSCs will help to develop novel therapeutic strategies for effective treatment of CML to possibly reach a cure. In recent years, a significant progress has been made in studying the biology of LSCs in both animal models and human patients at cellular and molecular levels, providing a basis for designing and testing potential molecular targets for eradicating LSCs in CML.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Células-Tronco Neoplásicas , Animais , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Células-Tronco Neoplásicas/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Pesquisa/tendências
18.
Mikrochim Acta ; 186(8): 558, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31338595

RESUMO

The author describe a method for preparation of green fluorescent nitrogen-doped carbon dots (N-CDs) through hydrothermal treatment of a mixture of lotus leaf juice and ethylenediamine (EDA). The N-CDs have uniform size, good dispersibility and water solubility. Under 316 and 366 nm photoexcitation, they show dual fluorescence with emission peaks at 415 and 509 nm, respectively. They are positively charge and display low cytotoxicity. This makes them an excellent choice for fluorometric assays and for bioimaging. A ratiometric assay was developed for the determination of the activity of acid phosphatase (ACP). It is based on the aggregation- induced quenching (AIQ) of the fluorescence of the N-CDs by sodium hexametaphosphate (NaPO3)6. Enzymatic hydrolysis of (NaPO3)6 by ACP leads to the disintegration of (NaPO3)6 and to the restoration of fluorescence. The measurement of the ratio of fluorescence at two wavelengths (415 and 509 nm), background interference and fluctuating signals can be widely eliminated. The method works in the 1-50 U·L-1 ACP activity range and has a detection limit of 0.43 U·L-1. It was successfully applied (a) to the determination of ACP in spiked serum samples, (b) to ACP inhibitor screening, and (c) to imaging of ACP in HePG2 cells. Graphical abstract Schematic presentation of the synthesis of nitrogen-doped carbon dots (N-CDs), and their application to the ratiometric fluorometric determination of acid phosphatase (ACP) based on the aggregation-induced quenching and enzymatic hydrolysis.


Assuntos
Fosfatase Ácida , Carbono/química , Corantes Fluorescentes/química , Nitrogênio/química , Fosfatase Ácida/análise , Fosfatase Ácida/antagonistas & inibidores , Fosfatase Ácida/sangue , Fosfatase Ácida/química , Química Verde , Células Hep G2 , Humanos , Lotus , Fosfatos/química , Extratos Vegetais/química , Folhas de Planta
19.
J Arthroplasty ; 34(6): 1287-1296, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30852065

RESUMO

BACKGROUND: Hip fracture is a significant health risk for older adults and malnutrition indicates hip fracture risk. METHODS: We evaluated whether nutrition status could predict clinical outcomes and mortality after hip fracture surgery in older adults. MEDLINE, Cochrane, EMBASE, and Google Scholar databases were searched for studies published until July 1, 2018, in patients with serum albumin or total lymphocyte count (TLC) at admission, nutritional status by Mini Nutritional Assessment (MNA), and in-hospital follow-up. Data extracted were analyzed using random-effects or fixed-effects models. RESULTS: Nineteen studies with 34,363 adults aged 74-85 years receiving hip fracture surgery were eligible for inclusion. Among these studies, 13 were screened for low albumin, 4 were evaluated for TLC, and 4 for nutritional status by MNA. Hypoalbuminemia was significantly associated with higher total mortality and higher risk of in-hospital death (both P < .001). Low TLC and MNA results "at risk of malnutrition" (hazard ratio, 1.67; 95% confidence interval = 1.28-2.18) and "malnourished" nutritional status (hazard ratio, 2.65; 95% CI = 1.81-3.88) also were significantly associated with higher total mortality (all P < .001). CONCLUSION: Low serum albumin level is a sole indicator for increased risk of in-hospital death, postoperative complications, and total mortality after hip fracture surgery in older adults. Low TLC and malnutrition classified by MNA predict increased mortality. These indicators provide valuable prognostic information and routine use may be prudent.


Assuntos
Artroplastia de Quadril/efeitos adversos , Avaliação Geriátrica , Fraturas do Quadril/cirurgia , Contagem de Linfócitos , Avaliação Nutricional , Albumina Sérica/análise , Idoso , Idoso de 80 Anos ou mais , Feminino , Consolidação da Fratura , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/mortalidade , Mortalidade Hospitalar , Hospitalização , Humanos , Masculino , Desnutrição/complicações , Estado Nutricional , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/mortalidade , Prognóstico , Modelos de Riscos Proporcionais
20.
J Cell Sci ; 129(16): 3130-43, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27358479

RESUMO

Leishmaniasis is a devastating disease that disfigures or kills nearly two million people each year. Establishment and persistence of infection by the obligate intracellular parasite Leishmania requires repeated uptake by macrophages and other phagocytes. Therefore, preventing uptake could be a novel therapeutic strategy for leishmaniasis. Amastigotes, the life cycle stage found in the human host, bind Fc receptors and enter macrophages primarily through immunoglobulin-mediated phagocytosis. However, the host machinery that mediates amastigote uptake is poorly understood. We have previously shown that the Arg (also known as Abl2) non-receptor tyrosine kinase facilitates L. amazonensis amastigote uptake by macrophages. Using small-molecule inhibitors and primary macrophages lacking specific Src family kinases, we now demonstrate that the Hck, Fgr and Lyn kinases are also necessary for amastigote uptake by macrophages. Src-mediated Arg activation is required for efficient uptake. Interestingly, the dual Arg and Src kinase inhibitor bosutinib, which is approved to treat cancer, not only decreases amastigote uptake, but also significantly reduces disease severity and parasite burden in Leishmania-infected mice. Our results suggest that leishmaniasis could potentially be treated with host-cell-active agents such as kinase inhibitors.


Assuntos
Imunoglobulina G/metabolismo , Leishmania/patogenicidade , Leishmaniose/parasitologia , Fagocitose , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-hck/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Quinases da Família src/metabolismo , Compostos de Anilina/farmacologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Mesilato de Imatinib/farmacologia , Leishmania/efeitos dos fármacos , Leishmaniose/enzimologia , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Macrófagos/parasitologia , Camundongos , Modelos Biológicos , Nitrilas/farmacologia , Parasitos/efeitos dos fármacos , Parasitos/parasitologia , Fagocitose/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Pirimidinas/farmacologia , Quinolinas/farmacologia , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA