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1.
World J Nucl Med ; 23(1): 33-42, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38595841

RESUMO

Objective The purpose of this study was to evaluate the prognostic significance of corrected baseline metabolic parameters in fluorodeoxyglucose positron emission tomography imaging ( 18 F-FDG PET/CT) for 3-year progression-free survival (PFS) in patients with primary diffuse large B cell lymphoma (DLBCL). Patients and Methods Retrospective clinical and pathological data were collected for 199 patients of DLBCL diagnosed between January 2018 and January 2021. All patients underwent 18 F-FDG PET/CT scans without any form of treatment. The corrected maximum standardized uptake value (corSUVmax), corrected mean standardized uptake value (corSUVmean), corrected whole-body tumor metabolic volume sum (corMTVsum), and corrected total lesion glycolysis of whole body (corTLGtotal) were corrected using the SUVmean in a 1-cm diameter mediastinal blood pool (MBP) from the descending thoracic aorta of patients. Kaplan-Meier survival curves and Cox regression were used to examine the predictive significance of corrected baseline metabolic parameters on 3-year PFS of patients. The incremental values of corrected baseline metabolic parameters were evaluated by using Harrell's C-indices, receiver operating characteristic, and Decision Curve Analysis. Results The multivariate analysis revealed that only the National Comprehensive Cancer Network (NCCN)-International Prognostic Index (IPI) and corMTVsum had an effect on 3-year PFS of patients ( p < 0.05, respectively). The Kaplan-Meier survival analysis demonstrated significant differences in PFS between the risk groups classified by corSUVsum, corMTVsum, and corTLGtotal (log-rank test, p < 0.05). The predictive model composed of corMTVsum and corTLGtotal surpasses the predictive performance of the model incorporating MTVsum and TLGtotal. The optimal performance was observed when corMTVsum was combined with NCCN-IPI, resulting in a Harrell's C index of 0.785 and area under the curve values of 0.863, 0.891, and 0.947 for the 1-, 2-, and 3-year PFS rates, respectively. Conclusion The corMTVsum offers significant prognostic value for patients with DLBCL. Furthermore, the combination of corMTVsum with the NCCN-IPI can provide an accurate prediction of the prognosis.

2.
Redox Biol ; 51: 102269, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35276443

RESUMO

Endothelial oxidative stress and inflammation attributable to the activation of a Nox2-NADPH oxidase are key features of many cardiovascular diseases. Here, we report a novel small chemical compound (LMH001, MW = 290.079), by blocking phosphorylated p47phox interaction with p22phox, inhibited effectively angiotensin II (AngII)-induced endothelial Nox2 activation and superoxide production at a small dose (IC50 = 0.25 µM) without effect on peripheral leucocyte oxidative response to pathogens. The therapeutic potential of LMH001 was tested using a mouse model (C57BL/6J, 7-month-old) of AngII infusion (0.8 mg/kg/d, 14 days)-induced vascular oxidative stress, hypertension and aortic aneurysm. Age-matched littermates of p47phox knockout mice were used as controls of Nox2 inhibition. LMH001 (2.5 mg/kg/d, ip. once) showed no effect on control mice, but inhibited completely AngII infusion-induced excess ROS production in vital organs, hypertension, aortic walls inflammation and reduced incidences of aortic aneurysm. LMH001 effects on reducing vascular oxidative stress was due to its inhibition of Nox2 activation and was abrogated by knockout of p47phox. LMH001 has the potential to be developed as a novel drug candidate to treat oxidative stress-related cardiovascular diseases.


Assuntos
Aneurisma Aórtico , Hipertensão , Angiotensina II/metabolismo , Animais , Aneurisma Aórtico/induzido quimicamente , Aneurisma Aórtico/genética , Aneurisma Aórtico/prevenção & controle , Hipertensão/induzido quimicamente , Hipertensão/tratamento farmacológico , Hipertensão/genética , Inflamação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADPH Oxidase 2/genética , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/farmacologia
3.
Sci Rep ; 10(1): 1582, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005915

RESUMO

Microglia express constitutively a Nox2 enzyme that is involved in neuroinflammation by the generation of reactive oxygen species (ROS). Amyloid ß (Aß) plays a crucial role in Alzheimer's disease. However, the mechanism of Aß-induced microglial dysfunction and redox-regulation of microgliosis in aging remains unclear. In this study, we examined Nox2-derived ROS in mediating microglial response to Aß peptide 1-42 (Aß42) stimulation in vitro, in aging-associated microgliosis in vivo and in post-mortem human samples. Compared to controls, Aß42 markedly induced BV2 cell ROS production, Nox2 expression, p47phox and ERK1/2 phosphorylation, cell proliferation and IL-1ß secretion. All these changes could be inhibited to the control levels in the presence of Nox2 inhibitor or superoxide scavenger. Compared to young (3-4 months) controls, midbrain tissues from wild-type aging mice (20-22 months) had significantly higher levels of Nox2-derived ROS production, Aß deposition, microgliosis and IL-1ß production. However, these aging-related changes were reduced or absent in Nox2 knockout aging mice. Clinical significance of aging-associated Nox2 activation, microgliosis and IL-1ß production was investigated using post-mortem midbrain tissues of humans at young (25-38 years) and old age (61-85 years). In conclusion, Nox2-dependent redox-signalling is crucial in microglial response to Aß42 stimulation and in aging-associated microgliosis and brain inflammation.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Microglia/metabolismo , NADPH Oxidase 2/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia de Fluorescência , Pessoa de Meia-Idade , Oxirredução , Fragmentos de Peptídeos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
4.
J Clin Invest ; 129(8): 3374-3386, 2019 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-31329158

RESUMO

Oxidative stress plays an important role in aging-related neurodegeneration. This study used littermates of WT and Nox2-knockout (Nox2KO) mice plus endothelial cell-specific human Nox2 overexpression-transgenic (HuNox2Tg) mice to investigate Nox2-derived ROS in brain aging. Compared with young WT mice (3-4 months), aging WT mice (20-22 months) had obvious metabolic disorders and loss of locomotor activity. Aging WT brains had high levels of angiotensin II (Ang II) and ROS production; activation of ERK1/2, p53, and γH2AX; and losses of capillaries and neurons. However, these abnormalities were markedly reduced in aging Nox2KO brains. HuNox2Tg brains at middle age (11-12 months) already had high levels of ROS production and activation of stress signaling pathways similar to those found in aging WT brains. The mechanism of Ang II-induced endothelial Nox2 activation in capillary damage was examined using primary brain microvascular endothelial cells. The clinical significance of Nox2-derived ROS in aging-related loss of cerebral capillaries and neurons was investigated using postmortem midbrain tissues of young (25-38 years) and elderly (61-85 years) adults. In conclusion, Nox2 activation is an important mechanism in aging-related cerebral capillary rarefaction and reduced brain function, with the possibility of a key role for endothelial cells.


Assuntos
Envelhecimento/metabolismo , Encéfalo , Capilares/enzimologia , Células Endoteliais , Endotélio Vascular/enzimologia , NADPH Oxidase 2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Envelhecimento/patologia , Animais , Encéfalo/irrigação sanguínea , Encéfalo/enzimologia , Encéfalo/patologia , Capilares/patologia , Células Endoteliais/enzimologia , Células Endoteliais/patologia , Endotélio Vascular/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , NADPH Oxidase 2/genética , Neurônios , Oxirredução
5.
Bull Environ Contam Toxicol ; 102(5): 721-729, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30756128

RESUMO

Mercury contamination in soil and water has become a major concern to environmental quality and human health. Among the existing remediation technologies for mercury pollution control, sorption via iron-based materials has received wide attention as they are environmental friendly and economic, and their reactivity is high and controllable through modulating the morphology and surface properties of particulate materials. This paper aimed to provide a comprehensive overview on environmental application of a variety of iron-based sorbents, namely, zero valent iron, iron oxides, and iron sulfides, for mercury remediation. Techniques to improve the stability of these materials while enhancing mercury sequestration, such as nano-scale size control, surface functionalization, and mechanical support, were summarized. Mechanisms and factors affecting the interaction between mercury and iron-based materials were also discussed. Current knowledge gaps and future research needs are identified to facilitate a better understanding of molecular-level reaction mechanisms between iron-based materials and mercury and the long-term stability of the immobilized mercury.


Assuntos
Recuperação e Remediação Ambiental/métodos , Ferro/química , Mercúrio/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Solo
6.
Sci Total Environ ; 657: 1450-1459, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30677911

RESUMO

The environmental implications of graphene oxide (GO) have received much attention. Transport of GO in subsurface environment is a critical process affecting the migration and potential risks of this important class of carbonaceous nanomaterials. To date, the effects of heterogeneity in porous media, in particular, iron oxides, on GO transport are not well studied. In this study, we investigated the transport properties of GO in saturate quartz sand as affected by the presence of iron oxides, using goethite, hematite and ferrihydrite as the model iron oxide species, and applied a two-site transport model (which accounts for both attachment and straining) to fit the transport data. We found that iron oxide coating on sand surfaces markedly inhibited GO transport, mainly due to increased electrostatic attraction between particles and collectors, as the positively charged iron oxides provided favorable deposition sites for the negatively charged GO nanosheets. Additionally, increased surface roughness was likely an additional mechanism leading to the enhanced GO deposition. The extent of transport inhibition by iron oxides also depended on the morphology iron oxides, in that at the same Fe loading a larger effect was observed when iron oxides existed as the coating on sand surface than as discreet particles. The presence of iron oxide coatings (tested using goethite) could magnify the effects of cations on GO transport. Specifically, the presence of goethite facilitated the accumulation of cations on the surface of sand, and in the case of Ca2+, the binding of GO via the cation-bridging mechanism was enhanced, as goethite contained abundant surface hydroxyl groups that are strong metal-complexing moieties.

7.
Infect Control Hosp Epidemiol ; 39(6): 701-709, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29655388

RESUMO

OBJECTIVETo assess the prevalence of healthcare-associated infections (HAIs) in mainland China.DESIGNSystematic review and meta-analysis.SETTINGAdults and children from secondary and tertiary acute-care hospitals in mainland China.METHODSWe searched PubMed, the China National Knowledge Infrastructure, and Wan Fang for multicenter point-prevalence surveys of acute-care hospitals in mainland China from January 2006 to August 2016. All reports related to HAI, using a point-prevalence methodology and published either in English or Chinese were eligible.RESULTSIn total, 3,021 publications were identified; 115 were eligible for quality assessment and data abstraction. The weighted HAI prevalence (95% confidence interval [CI]) overall, in general hospitals, children's hospitals, maternal and child health hospitals, and oncology hospitals were 3.12% (95% CI, 2.94%-3.29%), 3.02% (95% CI, 2.79%-3.26%), 4.43% (95% CI, 3.39%-5.47%), 1.88% (95% CI, 1.47%-2.29%), and 3.96% (95% CI, 3.12%-4.79%), respectively. In general hospitals, prevalence was highest in adult intensive care units (26.07%; 95% CI, 23.03%-29.12%), followed by surgery (3.26%; 95% CI, 2.96%-3.57%), and internal medicine (3.06%; 95% CI, 2.67%-3.46%). Overall, lower respiratory tract infection was the most frequent HAI (24,185, 47.28%), followed by urinary tract infection (5,773, 11.29%) and upper respiratory tract infection (5,194, 10.15%). Gram-negative bacilli were the most frequently isolated pathogens, and Pseudomonas aeruginosa (3,395, 14.91%), and Escherichia coli (2,918, 12.82%) were the most common single microorganisms.CONCLUSIONSThis study is the largest systematic review on the prevalence of HAI in mainland China. These results provide a benchmark for future PPSs and a reference for infection prevention and control strategies in mainland China.Infect Control Hosp Epidemiol 2018;39:701-709.


Assuntos
Infecção Hospitalar/epidemiologia , China/epidemiologia , Infecção Hospitalar/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/epidemiologia , Hospitais/estatística & dados numéricos , Humanos , Prevalência , Infecções Respiratórias/epidemiologia , Infecções Urinárias/epidemiologia
8.
Nat Prod Res ; 29(4): 388-91, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25112370

RESUMO

This study was designed to characterise the effects of evodiamine on intestinal contractility and reveal the correlated mechanisms. Evodiamine (2.5-80.0 µM) increased normal jejunal contractility and jejunal hypocontractility established under a variety of experimental conditions. Evodiamine-exerted stimulatory effects were blocked by the L-type Ca(2+) channel blocker nifedipine or abolished in the Ca(2+)-free assay condition. The stimulatory effects of evodiamine on jejunal contractility were partially blocked in the presence of neurotoxin tetrodotoxin or endogenous acetylcholine synthesis blocker hemicholinium-3 or muscarinic receptor antagonist atropine, respectively. Evodiamine-exerted stimulatory effects were blocked by c-kit receptor tyrosine kinase inhibitor imatinib. Evodiamine increased myosin phosphorylation in jejunal smooth muscle of constipation-prominent rats. These results showed that evodiamine-exerted stimulatory effects on jejunal segments are Ca(2+)-dependent, need the presence of interstitial cell of Cajal, requirement of cholinergic neuron and correlate with increased myosin phosphorylation, implicating the potential value of evodiamine in relieving hypo-motility disorders.


Assuntos
Jejuno/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Quinazolinas/farmacologia , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Motilidade Gastrointestinal/efeitos dos fármacos , Estrutura Molecular , Miosinas/metabolismo , Nifedipino/farmacologia , Fosforilação , Ratos , Tetrodotoxina/farmacologia
9.
J Nat Med ; 68(3): 530-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24658813

RESUMO

Ginsenoside Re (GRe) exerts diverse effects. Based on our observations, the present study was designed to investigate GRe-exerted bidirectional regulation (BR) on the contractility of isolated jejunal segment. Six pairs of different low and high contractile states of rat jejunal segment were established and used in the study. Stimulatory effects on the contractility of jejunal segment were exerted by GRe (10.0 µM) in all 6 low contractile states, and inhibitory effects were exerted in all 6 high contractile states, indicating that GRe exerted BR on the contractility of jejunal segment. The effects of GRe on the phosphorylation of 20 kDa myosin light chain, protein contents of myosin light chain kinase (MLCK) and MLCK mRNA expression in jejunal segment in low and high contractile states were also bidirectional. GRe-exerted BR was abolished in the presence of neurotoxin tetrodotoxin or Ca2+ channel blocker verapamil or c-Kit receptor tyrosine kinase inhibitor imatinib. Atropine blocked the stimulatory effects of GRe on jejunal contractility in low-Ca2+-induced low contractile state; phentolamine, propranolol and l-NG-nitro-arginine blocked the inhibitory effects in high-Ca2+-induced high contractile state, respectively. In summary, GRe-exerted BR depends on jejunal contractile state and requires the presence of enteric nervous system, Ca2+, and interstitial cells of Cajal; the stimulatory effects of GRe on jejunal contractility are related to cholinergic stimulation and inhibitory effects are related to adrenergic activation and nitric oxide relaxing mechanisms.


Assuntos
Ginsenosídeos/farmacologia , Jejuno/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Animais , Sistema Nervoso Entérico/fisiologia , Células Intersticiais de Cajal/fisiologia , Jejuno/inervação , Jejuno/metabolismo , Jejuno/fisiologia , Masculino , Quinase de Cadeia Leve de Miosina/metabolismo , Miosinas/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley
10.
Fitoterapia ; 94: 1-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24468189

RESUMO

Nobiletin, a citrus polymethoxylated flavone, exhibits multiple biological properties including anti-inflammatory, anti-carcinogenic, and anti-insulin resistance effects. The present study found that nobiletin exerted significant stimulatory effects on the contractility of isolated rat jejunal segments in all 6 different low contractile states, and meanwhile significant inhibitory effects in all 6 different high contractile states, showing characteristics of bidirectional regulation (BR). Nobiletin-exerted BR on jejunal contractility was abolished in the presence of c-kit receptor tyrosine kinase inhibitor imatinib or Ca(2+) channel blocker verapamil. In the presence of neuroxin tetrodotoxin, nobiletin only exerted stimulatory effects on jejunal contractility in both low and high contractile states. Hemicholinium-3 and atropine partially blocked nobiletin-exerted stimulatory effects on jejunal contractility in low-Ca(2+)-induced low contractile state. Phentolamine or propranolol or l-NG-nitro-arginine significantly blocked nobiletin-exerted inhibitory effects on jejunal contractility in high-Ca(2+)-induced high contractile state respectively. The effects of nobiletin on myosin light chain kinase (MLCK) mRNA expression, MLCK protein content, and myosin light chain phosphorylation extent were also bidirectional. In summary, nobiletin-exerted BR depends on the contractile states of rat jejunal segments. Nobiletin-exerted BR requires the enteric nervous system, interstitial cell of Cajal, Ca(2+), and myosin phosphorylation-related mechanisms.


Assuntos
Cálcio/metabolismo , Flavonas/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Animais , Atropina/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Sistema Nervoso Entérico/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Flavonas/química , Motilidade Gastrointestinal/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Jejuno/fisiologia , Masculino , Antagonistas Muscarínicos/farmacologia , Contração Muscular/efeitos dos fármacos , Quinase de Cadeia Leve de Miosina/efeitos dos fármacos , Quinase de Cadeia Leve de Miosina/genética , Miosinas/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley , Tetrodotoxina/farmacologia , Verapamil/farmacologia
11.
J Pharm Pharmacol ; 65(5): 734-44, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23600391

RESUMO

OBJECTIVES: The aim of the study was to evaluate berberine-induced bidirectional regulation on the contractility of jejunum. METHODS: Different low and high contractile states of isolated jejunal segment from rat were established to investigate the effects of berberine. KEY FINDINGS: Stimulatory effects on jejunal segment were exerted by berberine in six low contractile states and inhibitory effects were produced on jejunal segment in six high contractile states. The effects of berberine on myosin light chain kinase (MLCK) mRNA expression, MLCK protein content, and myosin phosphorylation in jejunum were also bidirectional. Bidirectional regulation was not observed in the presence of tetrodotoxin. No regulatory effects of berberine on jejunal contractility were observed in the presence of verapamil. The stimulatory effects of berberine on jejunal contractility were blocked by atropine. The inhibitory effects of berberine on jejunal contractility were abolished by phentolamine, propranolol and L-NG-nitro-arginine, respectively. CONCLUSIONS: Berberine-induced bidirectional regulation needed the presence of the enteric nervous system, and depended on the influx of extracellular Ca(2+) , related to the cholinergic system while jejunum was in low contractile states, and related to the adrenergic system and nitric oxide relaxing mechanism while jejunum was in high contractile states. The results suggested the potential clinical implication of berberine for alternating-type irritable bowel syndrome.


Assuntos
Adrenérgicos/farmacologia , Berberina/farmacologia , Colinérgicos/farmacologia , Motilidade Gastrointestinal/efeitos dos fármacos , Síndrome do Intestino Irritável , Jejuno/efeitos dos fármacos , Extratos Vegetais/farmacologia , Adrenérgicos/uso terapêutico , Animais , Arginina/farmacologia , Atropina/farmacologia , Berberina/uso terapêutico , Berberis/química , Cálcio/metabolismo , Colinérgicos/uso terapêutico , Sistema Nervoso Entérico , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/metabolismo , Síndrome do Intestino Irritável/fisiopatologia , Jejuno/metabolismo , Jejuno/fisiopatologia , Contração Muscular/efeitos dos fármacos , Quinase de Cadeia Leve de Miosina/genética , Quinase de Cadeia Leve de Miosina/metabolismo , Miosinas/metabolismo , Fosforilação , Fitoterapia , Extratos Vegetais/uso terapêutico , Propranolol/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Tetrodotoxina/farmacologia , Verapamil/farmacologia
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