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1.
BMC Musculoskelet Disord ; 25(1): 349, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702706

RESUMO

BACKGROUND: Although it is generally believed that the femoral neck fracture is related to the femoral neck geometric parameters (FNGPs), the association between the risk of osteoporotic fracture of the femoral neck and FNGPs in native Chinese women is still unclear. METHODS: A total of 374 female patients (mean age 70.2 ± 9.32 years) with osteoporotic fracture of the femoral neck, and 374 non-fracture control groups were completely matched with the case group according to the age ratio of 1:1. Using DXA bone densitometer to measured eight FNGPs: the outer diameter (OD), cross-sectional area (CSA), cortical thickness (CT), endocortical diameter (ED), buckling ratio (BR), section modulus (SM), cross-sectional moment of inertia (CSMI), and compressive strength index (CSI) at the narrowest point of the femoral neck. RESULTS: Compared with the control group, the average values of OD (2.9%), ED (4.5%), and BR (26.1%) in the patient group significantly increased (p = 0.015 to < 0.001), while CSA (‒15.3%), CT (‒18.2%), SM (‒10.3%), CSMI (‒6.4%), and CSI (‒10.8%) significantly decreased (all p < 0.001). The prevalence of osteoporosis in the lumbar spine, femoral neck, and total hip was, respectively, 82%, 81%, and 65% in fracture patients. Cox proportional hazard model analysis showed that in the age adjusted model, the fracture hazard ratio (HR) of CSA, CT, BR, SM, and CSI significantly increased (HRs = 1.60‒8.33; 95% CI = 1.08‒16.6; all p < 0.001). In the model adjusted for age and femoral neck BMD, HRs of CT (HRs = 3.90‒8.03; 95% CI = 2.45‒15.1; all p < 0.001) and BR (HRs = 1.62‒2.60; 95% CI = 1.20‒5.44; all p < 0.001) were still significantly increased. CONCLUSION: These results suggest that the majority of osteoporotic fractures of the femoral neck of native Chinese women occur in patients with osteoporosis. CT thinning or BR increase of FNGPs may be independent predictors of fragility fracture of femoral neck in native Chinese women unrelated to BMD.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Fraturas do Colo Femoral , Colo do Fêmur , Fraturas por Osteoporose , Humanos , Feminino , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas do Colo Femoral/diagnóstico por imagem , Fraturas do Colo Femoral/epidemiologia , Fraturas do Colo Femoral/etnologia , Idoso , Colo do Fêmur/diagnóstico por imagem , Pessoa de Meia-Idade , China/epidemiologia , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Povo Asiático , Fatores de Risco , População do Leste Asiático
2.
BMC Musculoskelet Disord ; 25(1): 187, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424521

RESUMO

BACKGROUND: Osteoporotic fractures are a growing problem in an aging society. The association between body mass index (BMI) and osteoporotic fractures varies by fracture site and ethnicity. Limited knowledge exists regarding this association in native Chinese, particularly utilizing local databases as reference sources. OBJECTIVE: To investigate the association between BMI and osteoporotic fractures at different sites in Chinese women. METHODS: Three thousand ninety-eight female patients with radiographic fractures and 3098 age- and sex-matched healthy controls without fractures were included in the study. Both of them underwent assessment using dual-energy X-ray absorptiometry (DXA), with BMD measurements calculated using our own BMD reference database. Participants were classified into underweight (BMI < 18.5 kg/m2), normal weight (18.5 ≤ BMI < 24.0 kg/m2), overweight (24 ≤ BMI < 28 kg/m2) and obese (BMI ≥ 28 kg/m2) according to the Chinese BMI classification standard. RESULTS: There were 2296 (74.1%) vertebral fractures, 374 (12.1%) femoral neck fractures, and 428 (13.8%) other types of fractures in the case group. Bone mineral density (BMD) was almost lower in the fracture groups compared to the control groups (p = 0.048 to < 0.001). Compared with normal weight, underweight had a protective effect on total [odds ratio (OR) = 0.61; 95% confidence interval (CI), 0.49 -0.75; P< 0.001], and lumbar fractures (OR = 0.52; 95% CI, 0.41 - 0.67; P < 0.001), while obesity was associated with an increased risk for total (OR = 2.26; 95% CI, 1.85 - 2.76; P < 0.001), lumbar (OR = 2.17; 95% CI, 1.72 - 2.73; P < 0.001), and femoral neck fractures (OR = 4.08; 95% CI, 2.18 - 7.63; P < 0.001). Non-linear associations were observed between BMI and fractures: A J-curve for total, lumbar, and femoral neck fractures, and no statistical change for other types of fractures. Underweight was found to be a risk factor for other types of fracturess after adjusting for BMD (OR = 2.29; 95% CI, 1.09 - 4.80; P < 0.001). Osteoporosis and osteopenia were identified as risk factors for almost all sites of fracture when compared to normal bone mass. CONCLUSIONS: Underweight has a protective effect on total and lumbar spine fractures in Chinese women, while obesity poses a risk factor for total, lumbar, and femoral neck fractures. The effect of BMI on fractures may be mainly mediated by BMD.


Assuntos
Fraturas do Colo Femoral , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Feminino , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/complicações , Índice de Massa Corporal , Estudos Retrospectivos , Magreza/complicações , Magreza/epidemiologia , Densidade Óssea , Absorciometria de Fóton , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/complicações , Fraturas do Colo Femoral/diagnóstico por imagem , Fraturas do Colo Femoral/epidemiologia , Fraturas do Colo Femoral/complicações , Obesidade/complicações , Obesidade/epidemiologia , Estudos de Casos e Controles , Vértebras Lombares/diagnóstico por imagem , China/epidemiologia
3.
Chaos ; 32(3): 033112, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35364823

RESUMO

This paper handles the distributed adaptive synchronization problem for a class of unknown second-order nonlinear multiagent systems subject to external disturbance. It is supposed to be an unknown one for the underlying external disorder. First, the neural network-based disturbance observer is developed to deal with the impact induced by the strange disturbance. Then, a new distributed adaptive synchronization criterion is put forward based on the approximation capability of the neural networks. Next, we propose the necessary and sufficient condition on the directed graph to ensure the synchronization error of all followers can be reduced small enough. Then, the distributed adaptive synchronization criterion is further explored because it is difficult to obtain the relative velocity measurements of the agents. The distributed adaptive synchronization criterion without the velocity measurement feedback is also designed to fulfill the current investigation. Finally, the simulation example is performed to verify the correctness and effectiveness of the proposed theoretical results.


Assuntos
Algoritmos , Redes Neurais de Computação , Simulação por Computador , Retroalimentação
4.
Nucleic Acids Res ; 47(D1): D464-D474, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30357411

RESUMO

The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB, rcsb.org), the US data center for the global PDB archive, serves thousands of Data Depositors in the Americas and Oceania and makes 3D macromolecular structure data available at no charge and without usage restrictions to more than 1 million rcsb.org Users worldwide and 600 000 pdb101.rcsb.org education-focused Users around the globe. PDB Data Depositors include structural biologists using macromolecular crystallography, nuclear magnetic resonance spectroscopy and 3D electron microscopy. PDB Data Consumers include researchers, educators and students studying Fundamental Biology, Biomedicine, Biotechnology and Energy. Recent reorganization of RCSB PDB activities into four integrated, interdependent services is described in detail, together with tools and resources added over the past 2 years to RCSB PDB web portals in support of a 'Structural View of Biology.'


Assuntos
Bases de Dados de Proteínas , Conformação Proteica , Pesquisa Biomédica/educação , Biotecnologia/educação , Curadoria de Dados , Software
5.
BMC Musculoskelet Disord ; 22(1): 728, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429080

RESUMO

BACKGROUND: Fragility fracture is associated with bone mineral density (BMD), and most databases used in related researches are instrument-matched. Little is known about the relationship between BMD and fragility fracture risk of native Chinese, especially using local databases as reference databases. OBJECTIVE: To investigate relationship between BMD and risk of fragility fracture in native China. METHODS: 3,324 cases, including 2,423 women (67.7 ± 8.9 years) and 901 men (68.4 ± 11.6 years) having radiological fragility fractures and 3,324 age- and gender-matched controls participated in the study. We measured BMD at posteroanterior spine and hip using dual-energy X-ray absorptiometry (DXA), calculated BMD measurement parameters based on our own BMD reference database. RESULTS: BMDs and mean T-scores were lower in case group (with clinical fragility) than in control group (without clinical fragility). In patients with fragility fractures, prevalence of lumbar osteoporosis, low bone mass, and normal BMD were 78.9 %, 19.3 %, and 1.8 %, respectively, in women, and 49.5, 44.8 %, and 5.7 %, respectively, in men. In hip, these prevalence rates were 67.2 %, 28.4 %, and 4.4 % in females, and 43.2 %, 45.9 %, and 10.9 % in males, respectively, showing differences between females and males. Multivariate Cox regression analysis showed that after adjusting age, height, weight, and body mass index, fracture hazard ratio (HR) increased by 2.7-2.8 times (95 % CI 2.5-3.1) and 3.6-4.1 times (95 %CI 3.0-5.1) for women and men respectively with decreasing BMD parameters. In both sexes, risk of fragility fracture increased approximately 1.6-1.7 times (95 % CI 1.5-1.8) for every 1 T-score reduction in BMD. CONCLUSIONS: Risk of clinical fragility fracture increases with decreasing BMD measurement parameters and anthropometric indicators in native China, and fracture HR varies from gender and site.


Assuntos
Densidade Óssea , Fraturas Ósseas , Estudos de Casos e Controles , China/epidemiologia , Feminino , Humanos , Vértebras Lombares , Masculino
6.
Pharmacol Res ; 152: 104603, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31863867

RESUMO

Berberine (BBR), a naturally-occurring isoquinoline alkaloid isolated from several Chinese herbal medicines, has been widely used for the treatment of dysentery and colitis. However, its blood concentration was less than 1 %, and intestinal microflora-mediated metabolites of BBR were considered to be the important material basis for the bioactivities of BBR. Here, we investigated the anti-colitis activity and potential mechanism of oxyberberine (OBB), a novel gut microbiota metabolite of BBR, in DSS-induced colitis mice. Balb/C mice treated with 3 % DSS in drinking water to induce acute colitis were orally administrated with OBB once daily for 8 days. Clinical symptoms were analyzed, and biological samples were collected for microscopic, immune-inflammation, intestinal barrier function, and gut microbiota analysis. Results showed that OBB significantly attenuated DSS-induced clinical manifestations, colon shortening and histological injury in the mice with colitis, which achieved similar therapeutic effect to azathioprine (AZA) and was superior to BBR. Furthermore, OBB remarkably ameliorated colonic inflammatory response and intestinal epithelial barrier dysfunction. OBB appreciably inhibited TLR4-MyD88-NF-κB signaling pathway through down-regulating the protein expressions of TLR4 and MyD88, inhibiting the phosphorylation of IκBα, and the translocation of NF-κB p65 from cytoplasm to nucleus. Moreover, OBB markedly modulated the gut dysbiosis induced by DSS and restored the dysbacteria to normal level. Taken together, the result for the first time revealed that OBB effectively improved DSS-induced experimental colitis, at least partly through maintaining the colonic integrity, inhibiting inflammation response, and modulating gut microflora profile.


Assuntos
Anti-Inflamatórios/uso terapêutico , Berberina/análogos & derivados , Berberina/uso terapêutico , Colite/tratamento farmacológico , Microbioma Gastrointestinal/fisiologia , Animais , Anti-Inflamatórios/farmacologia , Berberina/farmacologia , Biotransformação , Ceco/microbiologia , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Sulfato de Dextrana , Masculino , Camundongos Endogâmicos BALB C , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo
7.
J Enzyme Inhib Med Chem ; 33(1): 1362-1375, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30191728

RESUMO

In this study, we examined the anti-Helicobactor pylori effects of the main protoberberine-type alkaloids in Rhizoma Coptidis. Coptisine exerted varying antibacterial and bactericidal effects against three standard H. pylori strains and eleven clinical isolates, including four drug-resistant strains, with minimum inhibitory concentrations ranging from 25 to 50 µg/mL and minimal bactericidal concentrations ranging from 37.5 to 125 µg/mL. Coptisine's anti-H. pylori effects derived from specific inhibition of urease in vivo. In vitro, coptisine inactivated urease in a concentration-dependent manner through slow-binding inhibition and involved binding to the urease active site sulfhydryl group. Coptisine inhibition of H. pylori urease (HPU) was mixed type, while inhibition of jack bean urease was non-competitive. Importantly, coptisine also inhibited HPU by binding to its nickel metallocentre. Besides, coptisine interfered with urease maturation by inhibiting activity of prototypical urease accessory protein UreG and formation of UreG dimers and by promoting dissociation of nickel from UreG dimers. These findings demonstrate that coptisine inhibits urease activity by targeting its active site and inhibiting its maturation, thereby effectively inhibiting H. pylori. Coptisine may thus be an effective anti-H. pylori agent.


Assuntos
Antibacterianos/farmacologia , Berberina/análogos & derivados , Inibidores Enzimáticos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Urease/antagonistas & inibidores , Urease/química , Antibacterianos/química , Berberina/química , Berberina/farmacologia , Domínio Catalítico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Helicobacter pylori/enzimologia , Concentração de Íons de Hidrogênio , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Urease/metabolismo
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 39(2): 168-72, 2014 Feb.
Artigo em Zh | MEDLINE | ID: mdl-24608390

RESUMO

OBJECTIVE: To study the cerebrospinal fluid (CSF) flow through the aqueduct of sylvius in chronic tension-type headache patients with phase contrast magnetic resonance imaging. METHODS: Phase contrast magnetic resonance imaging (MRI) of the CSF flow through the aqueduct was obtained from 17 patients with chronic tension-type headache and 26 control subjects. A software for CSF flow was applied for MRI data analysis both qualitatively and quantitatively. RESULTS: The CSF through the aqueduct flew in the caudal and cranial directions with the rhythm of the heartbeat in both groups. There were 2 types of flow curves: the smooth "U" and the wave, which were 25 vs 1 in the controls and 11 vs 6 in the patients (P<0.05), respectively. The mean caudocranial flow rate through the aqueduct was (0.235±0.157) mL/s vs (0.133±0.106) mL/s (P<0.05) and the velocity was (6.023±2.654) cm/s vs (3.479±2.364) cm/s (P<0.05), and the mean craniocaudal flow rate was (-0.358±0.201) mL/s vs (-0.190±0.141) mL/s (P<0.05) and the velocity was (-8.263±3.020) cm/s vs (-4.788±2.862) cm/s (P<0.05), respectively. CONCLUSION: The CSF flow curve, rate and velocity through the aqueduct in the patients with chronic tension-type headache is anomalous in comparison with the controls.


Assuntos
Aqueduto do Mesencéfalo , Líquido Cefalorraquidiano/fisiologia , Imageamento por Ressonância Magnética , Cefaleia do Tipo Tensional/líquido cefalorraquidiano , Estudos de Casos e Controles , Humanos
9.
Neural Netw ; 172: 106090, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38176117

RESUMO

The multiagent systems have shared broad application in many practical systems including unmanned aircraft clusters, intelligent robots, and intelligent transportation. However, many unexpected cyber-attacks may disturb or disrupt the normal communication of the agents, thus reducing the interacting efficiency of multiagent systems. Ever since the cyber-attacks have been proposed, the resilient control problem for multiagent systems has been intensively explored in light of the communication network growth. However, most of the consequences only focused on denial-of-service (DoS) attacks or deception attacks independently. Distinguished from the existing resilient control mechanisms, the current investigation represents the first attempt at designing an adaptive resilient controller for multiagent systems according to the sampled-based adaptive event-triggered manner, where denial-of-service (DoS) attacks and deception attacks are both considered. First, the hybrid cyber-attacks model and its impact on the closed-loop system are addressed. And then, an adaptive event-triggered strategy is proposed to reduce network resource consumption and ease the communication burden, where the designed adaptive law can automatically adjust the triggering threshold. Finally, the consensus state of multiagent systems is capable of achieving via a series of reasonable control rules formulated through Lyapunov functional approach despite suffering hybrid cyber-attacks. And a simulation example is given to substantiate the feasibility of the proposed method.


Assuntos
Aeronaves , Resiliência Psicológica , Simulação por Computador , Consenso , Inteligência
10.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 42(5): 550-5, 2013 Sep.
Artigo em Zh | MEDLINE | ID: mdl-24167137

RESUMO

OBJECTIVE: To investigate the effect of renal sympathetic denervation on left ventricular hypertrophy and inflammatory factors in spontaneously hypertensive rats. METHODS: Thirty six spontaneously hypertensive rats (SHR) were divided into 3 groups with 12 animals in each group: SHR control group,operation group and sham operation group. Bilateral renal sympathectomy or sham operation were performed in operation and sham groups,respectively; another 12 WKY rats served as normal controls. The blood pressure and body weight were examined weekly. The animals were sacrificed at w1 and w6, rat hearts were collected and left ventricular mass index (LVMI) was calculated. The expression of TLR4,TNF-α and IL-6 in heart tissue were detected by immunohistochemistry and Western blot. RESULTS: The systolic blood pressure [(201.67 ± 11.09) mmHg compared with (140.0 ± 10.86)mmHg,P<0.05],diastolic blood pressure [(144.50 ± 10.48)mmHg compared with (78.50 ± 7.32)mmHg,P<0.05], LVMI (2.44 ± 0.05 compared with 1.93 ± 0.05,P<0.05),the expression of TLR4 (0.298 ± 0.004 compared with 0.126 ± 0.004, P<0.05), NF-κB (0.249 ± 0.006 compared with 0.195 ± 0.005, P<0.05),TNF-α(0.323 ± 0.004 compared with 0.146 ± 0.004,P <0.05), IL-6 (0.283 ± 0.005 compared with 0.207 ± 0.006, P<0.05) in SHR control group were significantly higher than those in WKY group. Compared to sham operation group,the systolic blood pressure (157.30 ± 9.35 compared with 197.30 ± 11.5, P<0.05),diastolic blood pressure (112.50 ± 6.25 compared with 146.80 ± 7.6, P<0.05),LVMI (2.32 ± 0.04 compared with 2.57 ± 0.09, P<0.05, TLR4 (0.198 ± 0.006 compared with 0.317 ± 0.008, P<0.05), NF-κB (0.208 ± 0.006 compared with 0.332 ± 0.007, P<0.05), TNF-α(0.27 ± 0.009 compared with 0.375 ± 0.004,P<0.05), IL-6 (0.218 ± 0.004 compared with 0.376 ± 0.009, P<0.05) in operation group were all decreased at w1 after sympathectomy. Six weeks after the operation,there were no significant differences in systolic blood pressure (197.50 ± 12.13 compared with 208.83 ± 10.23,P>0.05) and diastolic blood pressure (150.33 ± 7.74 compared with 151.50 ± 8.22, P>0.05) between denervated and sham-operated SHRs; however,the LVMI (2.46 ± 0.07 compared with 2.81 ± 0.05,P<0.05) and the expression of TLR4(0.301 ± 0.009 compared with 0.567 ± 0.006, P<0.05), NF-κB (0.251 ± 0.004 compared with 0.476 ± 0.009,P<0.05),TNF-α(0.324 ± 0.005 compared with 0.535 ± 0.006, P<0.05,IL-6 (0.285 ± 0.009 compared with 0.549 ± 0.007, P<0.05) in operation group were still significantly lower than those in sham operation group. CONCLUSION: Renal sympathetic denervation can significantly delay the progression of LVH in SHR, which may associated with lowering blood pressure and decreasing expression of TLR4, NF-κB,TNF-α, IL-6 in myocardial tissue.


Assuntos
Hipertrofia Ventricular Esquerda/cirurgia , Simpatectomia , Animais , Pressão Sanguínea , Interleucina-6/metabolismo , Rim/metabolismo , NF-kappa B/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 38(3): 245-50, 2013 Mar.
Artigo em Zh | MEDLINE | ID: mdl-23545820

RESUMO

OBJECTIVE: To diagnoze active ankylosing spondylitis (AAS) by magnetic resonance imaging (MRI). METHODS: MRI of the sacroiliac joint (SIJ) was performed on 48 patients who were clinically diagnosed as probable AS without radiologic evidence of sacroiliitis. Among them 21 were diagnozed as active sacroiliitis with MRI, whose examination was terminated; 27 whose MRI of SIJ did not diagnoze as active sacroiliitis were performed MRI in the thoracic spine. The diagnostic criteria of MRI for AAS of SIJ and/or the thoracic spine were fomulated by consulting documents. The definite diagnosis of AAS was finally made after follow-up for half a year. The sensitivity and specificity of the MRI of SIJ and/or MRI of thoracic spine were assessed. RESULTS: In the 48 patients without radiologic evidence of sacroiliitis, 38 were finally diagnosed as AAS, with established consensus criteria as reference standard. The sensitivity and specificity of the MRI of SIJ were 52.6% and 90.0%, and for the MRI of SIJ and/or the MRI of the thoracic spine 76.3% and 90.0%, respectively. CONCLUSION: Clinically probable AS without MRI evidence of sacroiliitis, MRI of the thoracic spine can increase the sensitivity of AAS diagnosis.


Assuntos
Imageamento por Ressonância Magnética , Articulação Sacroilíaca/patologia , Espondilite Anquilosante/diagnóstico , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Articulação Sacroilíaca/diagnóstico por imagem , Vértebras Torácicas/patologia , Adulto Jovem
12.
Microbiol Spectr ; 11(3): e0530222, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37140396

RESUMO

To investigate the combined function of the novel oral mTOR inhibitor, everolimus, with antifungal agents and their potential mechanisms against Exophiala dermatitidis, the CLSI microliquid-based dilution method M38-A2, chequerboard technique, and disk diffusion testing were performed. The efficacy of everolimus was evaluated in combination with itraconazole, voriconazole, posaconazole, and amphotericin B against 16 clinically isolated strains of E. dermatitidis. The synergistic effect was determined by measuring the MIC and fractional inhibitory concentration index. Dihydrorhodamine 123 was used for the quantification of ROS levels. The differences in the expression of antifungal susceptibility-associated genes were analyzed following different types of treatment. Galleria mellonella was used as the in vivo model. While everolimus alone showed minimal antifungal effects, combinations with itraconazole, voriconazole, posaconazole, or amphotericin B resulted in synergy in 13/16 (81.25%), 2/16 (12.5%), 14/16 (87.75%), and 5/16 (31.25%) of isolates, respectively. The disk diffusion assay revealed that the combination of everolimus and antifungal drugs showed no significant increase in the inhibition zones compared with the single agent, but no antagonistic effects were observed. Combination of everolimus and antifungal agents resulted in increased ROS activity (everolimus + posaconazole versus posaconazole [P < 0.05], everolimus + amphotericin B versus amphotericin B [P < 0.002]). Simultaneously, compared to mono-treatment, the combination of everolimus + itraconazole suppressed the expression of MDR2 (P < 0.05) and the combination of everolimus + amphotericin B suppressed the expression of MDR3 (P < 0.05) and CDR1B (P < 0.02). In vivo, combinations of everolimus and antifungal agents improved survival rates, particularly the combination of everolimus + amphotericin B (P < 0.05). In summary, the in vivo and in vitro experiments performed in our study suggest that the combination of everolimus with azoles or amphotericin B can have synergistic effects against E. dermatitidis, potentially due to the induction of ROS activity and inhibition of efflux pumps, providing a promising new approach for the treatment of E. dermatitidis infections. IMPORTANCE Cancer patients with E. dermatitidis infection have high mortality if untreated. Clinically, the conventional treatment of E. dermatitidis is poor due to the long-term use of antifungal drugs. In this study, we have for the first time investigated the interaction and action mechanism of everolimus combined with itraconazole, voriconazole, posaconazole, and amphotericin B on E. dermatitidis in vitro and in vivo, which provided new ideas and direction for further exploring the mechanism of drug combination and clinical treatment of E. dermatitidis.


Assuntos
Antifúngicos , Itraconazol , Humanos , Antifúngicos/farmacologia , Voriconazol/farmacologia , Itraconazol/farmacologia , Anfotericina B/farmacologia , Everolimo/farmacologia , Espécies Reativas de Oxigênio , Testes de Sensibilidade Microbiana
13.
Phytomedicine ; 116: 154862, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37216761

RESUMO

BACKGROUND: Monitoring target engagement at various stages of drug development is essential for natural product (NP)-based drug discovery and development. The cellular thermal shift assay (CETSA) developed in 2013 is a novel, broadly applicable, label-free biophysical assay based on the principle of ligand-induced thermal stabilization of target proteins, which enables direct assessment of drug-target engagement in physiologically relevant contexts, including intact cells, cell lysates and tissues. This review aims to provide an overview of the work principles of CETSA and its derivative strategies and their recent progress in protein target validation, target identification and drug lead discovery of NPs. METHODS: A literature-based survey was conducted using the Web of Science and PubMed databases. The required information was reviewed and discussed to highlight the important role of CETSA-derived strategies in NP studies. RESULTS: After nearly ten years of upgrading and evolution, CETSA has been mainly developed into three formats: classic Western blotting (WB)-CETSA for target validation, thermal proteome profiling (TPP, also known as MS-CETSA) for unbiased proteome-wide target identification, and high-throughput (HT)-CETSA for drug hit discovery and lead optimization. Importantly, the application possibilities of a variety of TPP approaches for the target discovery of bioactive NPs are highlighted and discussed, including TPP-temperature range (TPP-TR), TPP-compound concentration range (TPP-CCR), two-dimensional TPP (2D-TPP), cell surface-TPP (CS-TPP), simplified TPP (STPP), thermal stability shift-based fluorescence difference in 2D gel electrophoresis (TS-FITGE) and precipitate supported TPP (PSTPP). In addition, the key advantages, limitations and future outlook of CETSA strategies for NP studies are discussed. CONCLUSION: The accumulation of CETSA-based data can significantly accelerate the elucidation of the mechanism of action and drug lead discovery of NPs, and provide strong evidence for NP treatment against certain diseases. The CETSA strategy will certainly bring a great return far beyond the initial investment and open up more possibilities for future NP-based drug research and development.


Assuntos
Produtos Biológicos , Proteoma , Proteoma/metabolismo , Produtos Biológicos/farmacologia , Descoberta de Drogas/métodos , Ensaios de Triagem em Larga Escala/métodos , Sistemas de Liberação de Medicamentos
14.
J Mycol Med ; 33(4): 101417, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37619456

RESUMO

BACKGROUND: Candida infections of orthopedic implants are one of the most detrimental orthopedic implant-related complications with unsuccessful treatment and a poor prognosis. Most orthopedic Candida infections form biofilms and have resistance to the commonly used antifungal agents. This study aimed to develop a novel combination of normally prescribed drugs against Candida biofilm on orthopedic implants. METHODS: We cultured 26 clinical isolates of Candida strains to form biofilm without titanium sheets or on titanium sheets, which are the most commonly used materials for permanent or orthopedic implants. The checkerboard method was used to evaluate the synergistic effects of chlorhexidine (CHL) and azoles on these Candida biofilms. For the evaluation of synergistic effects, we constructed the cell viability assay by fluorescence staining and CFU reduction hot map of Candida. RESULTS: Twenty-six clinical isolates of Candida strains formed biofilm in 96-well plates without titanium sheets, and we selected 9 of them to form biofilm on titanium sheets in 24-well plates. In Candida biofilm formed in 96-wells, the synergistic rates of CHL with fluconazole, itraconazole, and voriconazole were 61% (16/26), 65% (17/26), and 23% (6/26), respectively. When compared to the blank control group, CHL monotherapy significantly inhibited biofilm formation on titanium sheets (P < 0.05). We demonstrated 100% synergistic rates of the CHL and fluconazole combination against Candida biofilm formation on titanium sheets, and the minimum inhibitory concentration of CHL and FLU decreased four- to eight-fold. CONCLUSIONS: We concluded that CHL combined with azoles inhibited the Candida biofilm formation 96-wells or on titanium sheets and has the potential to control the infections of orthopedic implants.


Assuntos
Candida , Candidíase , Humanos , Fluconazol/farmacologia , Azóis/farmacologia , Clorexidina/farmacologia , Titânio/farmacologia , Antifúngicos/farmacologia , Candidíase/microbiologia , Biofilmes , Testes de Sensibilidade Microbiana , Candida albicans
15.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 37(8): 829-33, 2012 Aug.
Artigo em Zh | MEDLINE | ID: mdl-22954924

RESUMO

OBJECTIVE: To investigate the impact of renal denervation on the blood pressure, plasma renalase content and expression of renalase and tyrosine hydroxylase (TH) in the idney of spontaneous hypertensive (SH) rats and to explore the role of renal denervation in lowering the blood pressure. METHODS: SH rats were randomly assigned into a baseline group, a surgery (renal denervation) group, a sham group and a control group (n=48). WKY rats matched in age (n=12) served as a baseline control group. All rats were housed until 12 weeks old. Then, the rats in the baseline group and the WKY group were sacrificed whose blood and kidney were collected for examination. In the renal denervation group, the sham group and the control group, the blood pressure was monitored continuously. One week and 6 weeks after the renal denervation, 6 rats in each group were sacrificed whose blood and kidney were collected. ELISA was employed to measure the plasma renalase and Western blot assay done to detect the expression of TH and renalase in the kidney. RESULTS: Compared with WKY rats, blood pressure significantly increased and TH protein expression markedly elevated (P<0.05) in SH rats in the baseline group, but plasma renalase content and protein expression of renalase in the kidney dramatically reduced (P<0.05). One week after the surgery, the mean arterial pressure and TH protein expression in the surgery group were lowered compared with the baseline group and dramatically reduced compared with the sham group and the control group (P<0.05). In the surgery group, the renalase level was markedly increased compared with the baseline group, the sham group, and the control group (P<0.05). Six weeks after the renal denervation, the mean arterial pressure and TH level in the surgery group were significantly increased but the renalase content and expression markedly reduced compared with those 1 week, but there were no marked differences among the surgery group, the sham group, and the control group (P>0.05). No pronounced differences in the above variables were found between the sham group and the control group at any time point (P>0.05). CONCLUSION: Renal denervation can lower the blood pressure, which may attribute to the suppression of sympathetic nerves, increase in plasma renalase content and renalase expression in the kidney.


Assuntos
Hipertensão/cirurgia , Rim/inervação , Monoaminoxidase/metabolismo , Simpatectomia/métodos , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Pressão Sanguínea/fisiologia , Rim/enzimologia , Masculino , Monoaminoxidase/sangue , Ratos , Ratos Endogâmicos SHR , Sistema Nervoso Simpático/fisiopatologia
16.
Chin Med ; 17(1): 59, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606807

RESUMO

Saponins are found in a variety of higher plants and display a wide range of pharmacological activities, including expectorant, anti-inflammatory, vasoprotective and antimicrobial properties. Pulsatilla chinensis (P. chinensis, Bai Tou Weng, ) has been used medically in China for thousands of years for the treatment of diseases caused by bacteria, and it is rich in triterpenoid saponins. In recent decades, anemoside B4 (Pulchinenoside C) is well studied since it has been used as a quality control marker for P. chinensis. At the same time, more and more other active compounds were found in the genus of Pulsatilla. In this review, we summarize the pharmacological activities of Pulsatilla saponins (PS) and discuss the cellular or molecular mechanisms that mediate their multiple activities, such as inducing cancer cell apoptosis, inhibiting tumor angiogenesis, and protecting organs via anti-inflammatory and antioxidant measures. We aim to provide comprehensive analysis and summary of research progress and future prospects in this field to facilitate further study and drug discovery of PS.

17.
Artigo em Inglês | MEDLINE | ID: mdl-36170388

RESUMO

The current investigation explores the leader-following consensus problem for nonlinear multiagent systems under the output feedback control mechanism and the event-triggered communication mechanism. Owing to the physical instrument constraints, a significant portion of the state variables is not readily available. Therefore, this article put forward a distributed event-based leader-following consensus protocol only using agents' relative output measurements and underlying neighbors. Furthermore, this article develops two event-triggered mechanisms simultaneously, one is the event-triggered communication mechanism in the sensor-to-controller channel, and another is the event-triggered controller update in the controller-to-actuator track. Besides that, it is proven that the developed event-triggered control protocol can settle the leader-following consensus problem of the nonlinear multiagent systems, and the Zeno behavior is excluded in both the channels. Finally, we perform two simulation examples to illustrate the efficacy of the obtained results.

18.
Front Cell Infect Microbiol ; 12: 864912, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35493742

RESUMO

Scedosporium and Lomentospora infections in humans are generally chronic and stubborn. The use of azoles alone cannot usually inhibit the growth of these fungi. To further explore the combined effect of multiple drugs and potential mechanisms of action, we tested the antifungal effects of tacrolimus (FK506) and everolimus in combination with azoles in vitro and in vivo on 15 clinical strains of Scedosporium/Lomentospora species and detected the level of Rhodamine 6G, ROS activity, and apoptosis. The in vitro results showed that the combinations of tacrolimus with itraconazole, voriconazole, and posaconazole showed synergistic effects on 9 strains (60%), 10 strains (73%), and 7 strains (47%), respectively, and the combinations of everolimus with itraconazole, voriconazole, and posaconazole showed synergistic effects on 8 strains (53%), 8 strains (53%), and 7 strains (47%), respectively. The synergistic effects might correspond to the elevated ROS activity (the tacrolimus + itraconazole group compared to the itraconazole group, (P < 0.05)), early apoptosis (itraconazole (P < 0.05) and voriconazole (P < 0.05) combined with everolimus), and late apoptosis (the tacrolimus + itraconazole group compared to the itraconazole group, (P < 0.01); the tacrolimus + posaconazole group compared to the posaconazole group, (P < 0.05)), but not inhibition of efflux pump activity. Our in vitro results suggested that a combination of tacrolimus or everolimus and azoles have a synergistic effect against Scedosporium/Lomentospora. The synergistic mechanisms of action might be triggering excessive ROS activity and apoptosis. In vivo, the survival rate of G. mellonella (sixth instar larvae) was significantly improved by tacrolimus alone, everolimus alone, azoles alone, and tacrolimus and everolimus combined with azoles separately (P < 0.05 for the tacrolimus group; P < 0.01 for the everolimus group and the itraconazole group; P = 0.0001 for the tacrolimus and posaconazole group; P < 0.0001 for other groups except the everolimus and itraconazole group, everolimus and posaconazole group, and tacrolimus and itraconazole group). From the results, we infer that the combination of tacrolimus or everolimus with azoles has obvious synergistic effect on Scedosporium/Lomentospora, and might enhance the level of apoptosis and necrosis. However, the synergistic effects were not related to the efflux pump. In conclusion, from our in vitro and in vivo study, tacrolimus and everolimus combined with azoles may have a synergistic effect in the treatment against Scedosporium/Lomentospora, improving the drug activity of azoles and promoting a better prognosis for patients.


Assuntos
Ascomicetos , Scedosporium , Azóis/farmacologia , Everolimo/farmacologia , Humanos , Itraconazol/farmacologia , Testes de Sensibilidade Microbiana , Espécies Reativas de Oxigênio , Tacrolimo/farmacologia , Voriconazol/farmacologia
19.
Front Cell Infect Microbiol ; 12: 936814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35865820

RESUMO

Multiple cellular activities, including protein and lipid synthesis, ribosome biogenesis, and metabolic processes, are regulated by the target of rapamycin (TOR) pathway. Recent research suggests that the TOR might play an important role in various physiological functions of pathogenic fungi, such as nutrient sensing, stress response, and cell cycle progression. Given their robust immunosuppressant and antitumor activities, TOR inhibitors are widely used in clinical settings. In the present study, a microdilution checkerboard-based approach was employed to assess the interactions between the oral mammalian target of rapamycin (mTOR) inhibitor everolimus (EVL) and antifungal agents in the treatment of Aspergillus species derived from 35 clinical isolates in vitro. The results revealed that EVL exhibited promising inhibitory synergy with itraconazole (ITC), posaconazole (POS), and amphotericin B (AMB) for 85.7%, 74.2%, and 71.4%, respectively. In contrast, EVL exhibited minimal synergistic inhibitory activity (14.3%) when applied in combination with voriconazole (VRC). Antagonistic interactions were not observed. In vivo experiments conducted in Galleria mellonella revealed that EVL in combination with antifungal agents improved the larva survival rates in the ITC, VRC, POS, and AMB groups by 18.3%, 13.3%, 26.7%, and 13.3%, respectively. These data suggest that the combination treatment with antifungal agents and antifungal agents holds promise as a means of alleviating clinical aspergillosis.


Assuntos
Antifúngicos , Everolimo , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergillus , Everolimo/farmacologia , Testes de Sensibilidade Microbiana , Voriconazol/farmacologia
20.
J Mycol Med ; 32(1): 101227, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34800920

RESUMO

BACKGROUND: Cryptococcus neoformans infections occur in immunocompromised patients, especially those with HIV infection, chemoradiotherapy after cancer, and organ transplantation. Infection can cause pneumonia and meningoencephalitis in severe cases with a high mortality rate if not treated. Although fluconazole and amphotericin B are the first-line treatments for cryptococcosis, the rate of fluconazole resistance has increased significantly due to long-term use. Minocycline is a derivative of tetracycline that exerts its antibacterial effect through inhibition of bacterial protein synthesis. It is also able to pass the blood-brain barrier to act on the central nervous system. The present study investigates the effects of minocycline in combination with antifungals in treating C. neoformans. OBJECTIVE: To determine in vitro interactions of minocycline combined with itraconazole, voriconazole, posaconazole, fluconazole and amphotericin B against C. neoformans. METHODS: The minimum inhibitory concentrations (MIC) of the antifungals were determined by the CLSI Clinical and Laboratory Standards Institute M27-A3 microdilution method. The in vitro synergistic effects of minocycline combined with itraconazole, voriconazole, posaconazole, fluconazole, and amphotericin B on C. neoformans were detected by the broth microdilution checkerboard technique and disk diffusion testing. RESULTS AND CONCLUSION: The working concentration ranges were 0.125-4 µg/mL for itraconazole, 0.03-0.125 µg/ml for voriconazole, 0.03-1 µg/ml for posaconazole, 0.25-16 µg/ml for fluconazole, and 0.125-2 µg/ml for amphotericin B. The synergistic rates of minocycline combinations against C. neoformans were 55% with itraconazole, 10% with voriconazole, 85% with posaconazole, 20% with fluconazole, and 70% with amphotericin B. The effective MIC value of minocycline in the synergistic combination decreased to 2-32 µg/ml, while the MIC of itraconazole decreased to 0.03-0.125 µg/ml, voriconazole 0.03-0.125 µg/ml, posaconazole 0.03-0.125 µg/ml, 0.125-4 µg/ml fluconazole, and 0.06-0.50 µg/ml amphotericin B. The disk diffusion assay showed that the plates containing minocycline and antifungal drugs produced inhibition zones with diameters larger than the single drug plates. Minocycline showed no antagonistic effect in the combinations. In conclusion, the combination of minocycline and azoles or amphotericin B has synergistic effects against C. neoformans in vitro.


Assuntos
Criptococose , Cryptococcus neoformans , Infecções por HIV , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Infecções por HIV/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Minociclina/farmacologia , Minociclina/uso terapêutico
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