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1.
Inorg Chem ; 63(9): 4249-4259, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38364203

RESUMEN

The emission of volatile organic compounds (VOCs) significantly contributes to air pollution and poses a serious threat to human health. Benzene, one of the most toxic VOCs, is difficult for the human body to metabolize and is classified as a Group 1 carcinogen. The development of efficient adsorbents for removing trace amounts of benzene from ambient air is thus of great importance. In this work, we studied the benzene adsorption properties of four Zr-based metal-organic frameworks (Zr-MOFs) through static volumetric and dynamic breakthrough experiments. Two previously reported Zr-MOFs, BUT-12 and STA-26, were prepared with a tritopic carboxylic acid ligand (H3L1) functionalized with three methyl groups, and STA-26 is a 2-fold interpenetrated network of BUT-12. Two new isoreticular Zr-MOFs, BUT-12-Et and STA-26-Et, were synthesized using a similar ligand, H3L2, where the methyl groups are replaced with ethyl groups. There are mesopores in BUT-12 and BUT-12-Et and micropores in STA-26 and STA-26-Et. The four Zr-MOFs all showed high stability in liquid water and acidic aqueous solutions. The microporous STA-26 and STA-26-Et showed much higher benzene uptakes than mesoporous BUT-12 and BUT-12-Et at room temperature under low pressures. Particularly, the benzene adsorption capacity of STA-26-Et was high up to 2.21 mmol/g at P/P0 = 0.001 (P0 = 12.78 kPa), higher than those of the other three Zr-MOFs and most reported solid adsorbents. Breakthrough experiments confirmed that STA-26-Et could effectively capture trace benzene (10 ppm) from dry air; however, its benzene capture capacity was reduced by 90% under humid conditions (RH = 50%). Coating of the crystals of STA-26-Et with polydimethylsiloxane (PDMS) increased the hydrophobicity of the exterior MOF surfaces, leading to a more than 2-fold improvement in its benzene capture capacity in the breakthrough experiment under humid condition. PDMS coating of STA-26-Et likely slowed down the water adsorption process, and thus, the adsorbent afforded more efficient capture of benzene. This work demonstrates that modifying both the interior and exterior surfaces of MOFs can effectively enhance their performance in capturing trace benzene from ambient air, even under humid conditions. This finding is meaningful for the development of new adsorbents for effective air purification applications.

2.
Int J Hyperthermia ; 41(1): 2323152, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38465646

RESUMEN

OBJECTIVES: This study was conducted to develop nomograms for predicting repeat intrahepatic recurrence (rIHR) and overall survival (OS), after radiofrequency ablation (RFA), treatment in patients with recurrent colorectal liver metastases (CLMs) after hepatectomy based on clinicopathologic features. METHODS: A total of 160 consecutive patients with recurrent CLMs after hepatectomy who were treated with ultrasound-guided percutaneous RFA from 2012 to 2022 were retrospectively included. Patients were randomly divided into a training cohort and a validation cohort, with a ratio of 8:2. Potential prognostic factors associated with rIHR and OS, after RFA, were identified by using the competing-risks and Cox proportional hazard models, respectively, and were used to construct the nomogram. The nomogram was evaluated by Harrell's C-index and a calibration curve. RESULTS: The 1-, 2-, and 3-year rIHR rates after RFA were 58.8%, 70.2%, and 74.2%, respectively. The 1-, 3- and 5-year OS rates were 96.3%, 60.4%, and 38.5%, respectively. In the multivariate analysis, mutant RAS, interval from hepatectomy to intrahepatic recurrence ≤ 12 months, CEA level >5 ng/ml, and ablation margin <5 mm were the independent predictive factors for rIHR. Mutant RAS, largest CLM at hepatectomy >3 cm, CEA level >5 ng/ml, and extrahepatic disease were independent predictors of poor OS. Two nomograms for rIHR and OS were constructed using the respective significant variables. In both cohorts, the nomogram demonstrated good discrimination and calibration. CONCLUSIONS: The established nomograms can predict individual risk of rIHR and OS after RFA for recurrent CLMs and contribute to improving individualized management.


Asunto(s)
Ablación por Catéter , Neoplasias Colorrectales , Neoplasias Hepáticas , Ablación por Radiofrecuencia , Humanos , Neoplasias Colorrectales/patología , Neoplasias Hepáticas/patología , Recurrencia Local de Neoplasia/cirugía , Nomogramas , Pronóstico , Estudios Retrospectivos
3.
Inorg Chem ; 62(31): 12329-12336, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37478416

RESUMEN

Propyne/propylene separation is important in the petrochemical industry but challenging due to their similar physical properties and close molecular sizes. Metal-organic frameworks (MOFs) are a class of promising adsorbents for light hydrocarbon separations. Among them, the so-called "flexible-robust" MOFs combine the advantages of flexibility and rigidity in structure and could show enhanced gas separation selectivity as well as improved gas uptake at low pressure. Interpenetrated MOFs offer a platform to explore the "flexible-robust" feature of MOFs based on their subnetwork displacement in the process of gas adsorption. Herein, we present two hydrolytically stable MOFs (BUT-308 and BUT-309) with interpenetrated structures and fascinating propyne/propylene separation performance. BUT-308 is composed of interpenetrated 2D Cu(BDC-NH2)BPB layers (H2BDC-NH2 = 2-aminobenzene-1,4-dicarboxylic acid; BPB = 1,4-bis(4-pyridyl)benzene), while BUT-309 consists of twofold interpenetrated 3D pillared-layer Cu2(BDC-NH2)2(BPB-CF3) nets (BPB-CF3 = 2-trifluoromethyl-1,4-bis(4-pyridyl)benzene). Gas adsorption measurements showed that BUT-309 was a "flexible-robust" adsorbent with multistep adsorption isotherms for C3H4 rather than C3H6 at a wide temperature range. The guest-dependent pore-opening behavior endows BUT-309 with high potential in the C3H4/C3H6 separation. The C3H4 adsorption measurements of BUT-309 at 273-323 K showed that the lowering of the temperature induced the pore-opening action at lower pressure. Column breakthrough experiments further confirmed the capability of BUT-309 for the efficient removal of C3H4 from a C3H4/C3H6 binary gas, and the C3H6 processing capacity at 273 K (15.7 cm3 g-1) was higher than that at 298 K (35.2 cm3 g-1). This work shows a rare example of "flexible-robust" MOFs and demonstrated its high potential for C3H4/C3H6 separation.

4.
Zhongguo Zhong Yao Za Zhi ; 48(17): 4693-4701, 2023 Sep.
Artículo en Zh | MEDLINE | ID: mdl-37802808

RESUMEN

This study aimed to examine the effect and underlying mechanism of Puerariae Lobatae Radix on insulin resistance in db/db mice with type 2 diabetes mellitus(T2DM) based on the analysis of intestinal flora. Fifty db/db mice were randomly divided into a model group(M group), a metformin group(YX group), a high-dose Puerariae Lobatae Radix group(YGG group), a medium-dose Puerariae Lobatae Radix group(YGZ group), and a low-dose Puerariae Lobatae Radix group(YGD group). Another 10 db/m mice were assigned to the normal group(K group). After continuous administration for eight weeks, body weight and blood sugar of mice were measured. Enzyme linked immunosorbent assay(ELISA) was used to detect glycosylated serum protein(GSP) and fasting serum insulin(FINS), and insulin resistance index(HOMA-IR) was calculated. The histopathological changes in the pancreas were observed by HE staining. Tumor necrosis factor(TNF)-α expression in the pancreas was detected using immunohistochemistry. The structural changes in fecal intestinal flora in the K, M, and YGZ groups were detected by 16S rRNA. Western blot was used to detect the expression of farnesoid X receptor(FXR) and takeda G protein-coupled receptor 5(TGR5) in the ileum, cholesterol 7α-hydroxylase(CYP7A1) and sterol 27α-hydroxylase(CYP27A1) in the liver, and G protein-coupled receptors 41(GPR41) and 43(GPR43) in the colon. Compared with the K group, the M group showed increased body weight, blood sugar, serum GSP, fasting blood glucose(FBG), and FINS, increased HOMA-IR, inflammatory infiltration of islet cells, necrosis and degeneration of massive acinar cells, unclear boundary between islet cells and acinar cells, disturbed intestinal flora, and down-regulated FXR, TGR5, CYP7A1, CYP27A1, GPR41, and GPR43. Compared with the M group, the YX, YGG, YGZ, and YGD groups showed decreased body weight, blood sugar, serum GSP, FBG, and FINS, islet cells with intact and clumpy morphology and clear boundary, necrosis of a few acinar cells, and more visible islet cells. The intestinal flora in the YGZ group changed from phylum to genus levels, and the relative abundance of intestinal flora affecting the metabolites of intestinal flora increased. The protein expression of FXR, TGR5, CYP7A1, CYP27A1, GPR41, and GPR43 increased. The results show that Puerariae Lobatae Radix can improve the inflammatory damage of pancreatic islet cells and reduce insulin resistance in db/db mice with T2DM. The mechanism of action may be related to the increase in the abundance of Actinobacteria, Bifidobacterium, and Bacteroides in the intestinal tract and the protein expression related to metabolites of intestinal flora.


Asunto(s)
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Resistencia a la Insulina , Pueraria , Ratones , Animales , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Pueraria/química , ARN Ribosómico 16S , Peso Corporal , Necrosis
5.
J Neurochem ; 161(3): 293-307, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35244207

RESUMEN

The role of α1 adrenergic receptors (α1-ARs) signaling pathway in the pathogenesis of Alzheimer's disease (AD) has rarely been investigated. Clarifying the pathophysiological functions of α1-ARs in the AD brain is helpful for better understanding the pathogenesis and screening novel therapeutic targets of AD. This study included 2 arms of in vivo investigations: 1) 6-month-old female APPswe/PS1 mice were intravenously treated with AAV-PHP.eB-shRNA (α1-ARs)-GFP or AAV-PHP.eB-GFP for 3 months. 2) 3-month-old female APPswe/PS1 mice were daily treated with 0.5 mg/kg terazosin or an equal volume of saline for 6 months. SH-SY5Y cell lines bearing human amyloid precursor protein were treated with terazosin or saline for investigating possible mechanisms. α1-ARs knockdown mice exhibited improved behavioral performances in comparison with control mice. α1-ARs knockdown mice had significantly lower brain amyloid burden, as reflected by soluble Aß species, compact and total Aß plaques, than control mice. α1-ARs inhibitor terazosin substantially reduced Aß deposition, attenuated downstream pathologies including tau hyperphosphorylation, glial activation, neuronal loss, synaptic dysfunction et al., and rescued behavioral deficits in APPswe/PS1 mice. In vitro investigation demonstrated that α1-ARs inhibition down-regulated BACE1 expression, and promoted ser9 phosphorylation of GSK-3ß, thus reducing Aß production. This study indicates that inhibition of α1-ARs signaling pathway might represent a promising therapeutic strategy for AD.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Ácido Aspártico Endopeptidasas/metabolismo , Modelos Animales de Enfermedad , Femenino , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Ratones , Ratones Transgénicos , Receptores Adrenérgicos/uso terapéutico , Transducción de Señal
6.
J Clin Ultrasound ; 50(2): 216-221, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35084048

RESUMEN

PURPOSE: To investigate the differential diagnostic value of computer-aided color parametric imaging (CPI) and contrast-enhanced ultrasound (CEUS) in hepatocellular adenoma (HCA) and well-differentiated hepatocellular carcinoma (wHCC). METHOD: A total of 38 patients who underwent CEUS and were pathologically diagnosed with HCA (10 cases) and wHCC (28 cases) were reviewed retrospectively. The differences between the radiological features of HCA and wHCC were compared by two readers, blinded to the final diagnosis. RESULTS: (a) Sonographic features: on gray-scale ultrasound, halo sign was more common in wHCC than in HCA (60.7% vs. 10.0%, p = 0.009). On CEUS, hyper- or isoenhancement was more common in HCA in the portal phase (90.0% vs. 50.0%; p = 0.022). On CPI mode, HCA was inclined toward centripetal enhancement (60.0% vs. 14.3% p = 0.010). HCA was characterized by the presence of pseudocapsule enhancement (50.0% vs. 14.3%; p = 0.036). Quantitative analysis showed that the arrival time of HCA was earlier than that of wHCC (12.4 ± 3.7 s vs. 15.9 ± 3.2 s; p = 0.006). (b) Interobserver agreement was improved by using CPI compared with CEUS. The diagnostic sensitivity, specificity, and accuracy of the combination were 80.0%, 85.7%, and 84.2%, respectively. CONCLUSIONS: CEUS combined with CPI can provide effective information for the differential diagnosis of HCA and wHCC, especially for the non-experienced radiologists.


Asunto(s)
Adenoma de Células Hepáticas , Carcinoma Hepatocelular , Neoplasias Hepáticas , Adenoma de Células Hepáticas/diagnóstico por imagen , Carcinoma Hepatocelular/diagnóstico por imagen , Medios de Contraste , Diagnóstico Diferencial , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Estudios Retrospectivos , Sensibilidad y Especificidad , Ultrasonografía
7.
Zhongguo Zhong Yao Za Zhi ; 47(21): 5863-5871, 2022 Nov.
Artículo en Zh | MEDLINE | ID: mdl-36472005

RESUMEN

This study deciphered the mechanism of Shenling Baizhu Powder in treatment of mouse model of ulcerative colitis(UC) via NOD-like receptor thermoprotein domain 3(NLRP3) signaling pathway. After three days of adaptive feeding, 70 SPF-grade BALB/c mice were randomized into 7 groups: normal group, model group(dextran sodium sulfate, DSS), mesalazine group(DSS + 5-aminosalicylic acid, 5-ASA), NLRP3 inhibitor group(DSS + MCC950), and high-, medium-, and low-dose Shenling Baizhu Powder groups(DSS + high-, medium-, and low-dose Shenling Baizhu Powder), with 10 mice per group. The normal group had free access to double distilled water, and the remaining groups had free access to DSS-containing water to establish the acute UC model. Intragastric administration was started at the same time as modeling for one week. During the experiment, the general mental state and disease activity of each group of mice were recorded and scored. After the experiment, colon and serum samples were collected. The pathological changes in colon tissue were observed through hematoxylin-eosin(HE) staining. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the levels of interleukin-18(IL-18) and myeloperoxidase(MPO) in colon tissue and interleukin-1ß(IL-1ß) in serum. Immunofluorescence(IF) and immunohistochemistry(IHC) methods were employed to examine the expression of NLRP3 and IL-18 in colon tissue. Western blot was employed to measure the protein levels of NLRP3, apoptosis-associated speck-like protein(ASC), cystein-aspartate protease 1(caspase-1), and downstream inflammatory cytokines in colon tissue. Compared with the normal group, the modeling of UC increased the disease activity index(DAI), colon pathological injury score, IL-1ß level in serum, and IL-18 and MPO levels in colon tissue(P<0.05, P<0.01). Furthermore, the modeling caused obvious pathological changes and up-regulated the expression of NLRP3, caspase-1, ASC, pro-IL-1ß, cleaved-IL-1ß, pro-IL-18, and cleaved-IL-18 in the colon(P<0.01). Compared with the model group, the administration of corresponding drugs decreased the DAI, pathological injury score, IL-1ß level in serum, and IL-18 and MPO levels in colon tissue, and down-regulated the protein levels of NLRP3, caspase-1, ASC, pro-IL-1ß, cleaved-IL-1ß, pro-IL-18, and cleaved-IL-18 in the colon(P<0.05, P<0.01). According to the results of previous study and this study, we concluded that Shenling Baizhu Powder can alleviate the inflammatory response and intestinal damage of DSS-induced UC by regulating the expression of the proteins and inflammatory cytokines associated with NLRP3 signaling pathway.


Asunto(s)
Colitis Ulcerosa , Colitis , Ratones , Animales , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Sulfato de Dextran/efectos adversos , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Interleucina-18/genética , Polvos , Colon/metabolismo , Caspasa 1 , Mesalamina/efectos adversos , Ratones Endogámicos BALB C , Modelos Animales de Enfermedad , Citocinas/metabolismo , Agua , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/patología
8.
Phys Chem Chem Phys ; 22(31): 17559-17566, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32716426

RESUMEN

The absorption and fluorescence spectra of 4-(3-methoxybenzylidene)-2-methyl-oxazalone (m-MeOBDI) dissolved in neutral, acidic, and basic solvent environments have been investigated and assigned by using Franck-Condon (FC) simulations at the quantum TDDFT level. Four different structures of m-MeOBDI in the ground and excited states are optimized and are found to be responsible for the observed absorption and fluorescence spectra. The (absorption) fluorescence of m-MeOBDI in pure methanol and neutral/basic methanol/water (1/9 vol) mixed solvent is found to arise from the (ground neutral N-I) excited neutral N-I* and cationic C-III* species, respectively. In acidic solvent, the absorption is found to arise from ground acidic C-II species, and the excited divalent cation DC-IV* is found to be formed in its excited state due to the excess H+ in the solution, and then it emits ∼560 nm fluorescence. FC simulations have also been employed to confirm our assignments as well as interpret the vibronic band profiles. As expected, the simulated emission spectrum of the divalent cationic species is in good agreement with the experimental observation. Therefore, within the present FC simulation, the observed absorption and fluorescence spectra have been reasonably interpreted and novel fluorescence mechanisms of m-MeOBDI in various pH solvent environments have been proposed.

9.
Neurobiol Dis ; 132: 104567, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31394202

RESUMEN

Neurofibrillary tangles of hyperphosphorylated tau protein (p-tau) are a key pathological feature of Alzheimer's disease (AD). Tau phosphorylation is suggested to be secondary to amyloid-beta (Aß) accumulation. However, the mechanism by which Aß induces tau phosphorylation in neurons remains unclear. Neurotrophin receptor p75 (p75NTR) is a receptor for Aß and mediates Aß neurotoxicity, implying that p75NTR may mediate Aß-induced tau phosphorylation in AD. Here, we showed that Aß-induced tau hyperphosphorylation and neurodegeneration, including tau phosphorylation, synaptic disorder and neuronal loss, in the brains of both male wild-type (Wt) mice and male P301L transgenic mice (a mouse model of human tauopathy) were alleviated by genetic knockout of p75NTR in the both mouse models. We further confirmed that the activation or inhibition of cyclin-dependent kinase 5 (CDK5) and glycogen synthase kinase-3ß (GSK3ß) significantly changed Aß/p75NTR-mediated p-tau levels in neurons. Treatment of male P301L mice with soluble p75NTR extracellular domain (p75ECD-Fc), which antagonizes the binding of Aß to p75NTR, suppressed tau hyperphosphorylation. Taken together, our findings suggest that p75NTR meditates Aß-induced tau pathology and is a potential druggable target for AD and other tauopathies.


Asunto(s)
Péptidos beta-Amiloides/toxicidad , Receptores de Factor de Crecimiento Nervioso/metabolismo , Tauopatías/metabolismo , Proteínas tau/metabolismo , Animales , Células Cultivadas , Masculino , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Distribución Aleatoria , Receptores de Factor de Crecimiento Nervioso/administración & dosificación , Receptores de Factor de Crecimiento Nervioso/genética , Tauopatías/tratamiento farmacológico , Tauopatías/genética , Proteínas tau/antagonistas & inhibidores , Proteínas tau/genética
10.
Mol Psychiatry ; 23(8): 1813-1824, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29867188

RESUMEN

Tau pathology is characterized as a form of frontotemporal lobar degeneration (FTLD) known as FTLD-tau. The underlying pathogenic mechanisms are not known and no therapeutic interventions are currently available. Here, we report that the neurotrophin receptor p75NTR plays a critical role in the pathogenesis of FTLD-tau. The expression of p75NTR and the precursor of nerve growth factor (proNGF) were increased in the brains of FTLD-tau patients and mice (P301L transgenic). ProNGF-induced tau phosphorylation via p75NTR in vitro, which was associated with the AKT/glycogen synthase kinase (GSK)3ß pathway. Genetic reduction of p75NTR in P301L mice rescued the memory deficits, alleviated tau hyperphosphorylation and restored the activity of the AKT/GSK3ß pathway. Treatment of the P301L mice with the soluble p75NTR extracellular domain (p75ECD-Fc), which can antagonize neurotoxic ligands of p75NTR, effectively improved memory behavior and suppressed tau pathology. This suggests that p75NTR plays a crucial role in tau paGSKthology and represents a potential druggable target for FTLD-tau and related tauopathies.


Asunto(s)
Degeneración Lobar Frontotemporal/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Precursores de Proteínas/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Proteínas tau/metabolismo , Animales , Encéfalo/metabolismo , Encéfalo/patología , Células Cultivadas , Femenino , Degeneración Lobar Frontotemporal/patología , Degeneración Lobar Frontotemporal/terapia , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Masculino , Trastornos de la Memoria/metabolismo , Trastornos de la Memoria/patología , Trastornos de la Memoria/terapia , Ratones Transgénicos , Neuronas/metabolismo , Neuronas/patología , Fosforilación/fisiología , Cultivo Primario de Células , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
11.
Acta Neuropathol ; 136(4): 525-536, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30074071

RESUMEN

Accumulation of pathological tau is the hallmark of Alzheimer's disease and other tauopathies and is closely correlated with cognitive decline. Clearance of pathological tau from the brain is a major therapeutic strategy for tauopathies. The physiological capacity of the periphery to clear brain-derived tau and its therapeutic potential remain largely unknown. Here, we found that cisterna magna injected 131I-labelled synthetic tau dynamically effluxed from the brain and was mainly cleared from the kidney, blood, and liver in mice; we also found that plasma tau levels in inferior vena cava were lower than those in femoral artery in humans. These findings suggest that tau proteins can efflux out of the brain and be cleared in the periphery under physiological conditions. Next, we showed that lowering blood tau levels via peritoneal dialysis could reduce interstitial fluid (ISF) tau levels in the brain, and tau levels in the blood and ISF were dynamically correlated; furthermore, tau efflux from the brain was accelerated after the addition of another set of peripheral system in a parabiosis model. Finally, we established parabiosis mouse models using tau transgenic mice and their wild-type littermates and found that brain tau levels and related pathologies in parabiotic transgenic mice were significantly reduced after parabiosis, suggesting that chronic enhancement of peripheral tau clearance alleviates pathological tau accumulation and neurodegeneration in the brain. Our study provides the first evidence of physiological clearance of brain-derived pathological tau in the periphery, suggesting that enhancing peripheral tau clearance is a potential therapeutic strategy for tauopathies.


Asunto(s)
Sistema Nervioso Periférico/metabolismo , Tauopatías/metabolismo , Tauopatías/terapia , Proteínas tau/metabolismo , Adulto , Anciano , Animales , Química Encefálica , Cisterna Magna/metabolismo , Líquido Extracelular/metabolismo , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Persona de Mediana Edad , Parabiosis , Diálisis Peritoneal , Distribución Tisular , Vena Cava Inferior/metabolismo , Proteínas tau/genética
12.
Proc Natl Acad Sci U S A ; 112(16): 5225-30, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25847999

RESUMEN

Alzheimer's disease (AD) is one of most devastating diseases affecting elderly people. Amyloid-ß (Aß) accumulation and the downstream pathological events such as oxidative stress play critical roles in pathogenesis of AD. Lessons from failures of current clinical trials suggest that targeting multiple key pathways of the AD pathogenesis is necessary to halt the disease progression. Here we show that Edaravone, a free radical scavenger that is marketed for acute ischemic stroke, has a potent capacity of inhibiting Aß aggregation and attenuating Aß-induced oxidation in vitro. When given before or after the onset of Aß deposition via i.p. injection, Edaravone substantially reduces Aß deposition, alleviates oxidative stress, attenuates the downstream pathologies including Tau hyperphosphorylation, glial activation, neuroinflammation, neuronal loss, synaptic dysfunction, and rescues the behavioral deficits of APPswe/PS1 mice. Oral administration of Edaravone also ameliorates the AD-like pathologies and memory deficits of the mice. These findings suggest that Edaravone holds a promise as a therapeutic agent for AD by targeting multiple key pathways of the disease pathogenesis.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Antipirina/análogos & derivados , Trastornos del Conocimiento/tratamiento farmacológico , Administración Oral , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/patología , Amiloide/metabolismo , Péptidos beta-Amiloides/toxicidad , Animales , Antipirina/administración & dosificación , Antipirina/química , Antipirina/farmacología , Antipirina/uso terapéutico , Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/patología , Línea Celular , Trastornos del Conocimiento/complicaciones , Trastornos del Conocimiento/patología , Dendritas/efectos de los fármacos , Dendritas/patología , Edaravona , Humanos , Inflamación/patología , Ratones Transgénicos , Neurotoxinas/toxicidad , Estrés Oxidativo/efectos de los fármacos , Fosforilación/efectos de los fármacos , Presenilina-1/metabolismo , Agregación Patológica de Proteínas/complicaciones , Agregación Patológica de Proteínas/tratamiento farmacológico , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteínas tau/metabolismo
13.
J Stroke Cerebrovasc Dis ; 27(7): 1992-1997, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29673615

RESUMEN

BACKGROUND: To investigate the effects of abdominal obesity (AO) and nonalcoholic fatty liver disease (NAFLD) with or without AO on carotid arteries by determining carotid intima-media thickness (CIMT). METHODS: A total of 2745 Chinese Han adults (aged between 40 and 50 years old) were recruited and divided into 4 groups: (1) NW-no NAFL group: the normal body weight without NAFLD (n = 1888); (2) AO-no NAFL group: AO without NAFLD (n = 259); (3) NW-with NAFL group: NAFLD without AO (n = 93); and (4) AO-with NAFL group: AO with NAFLD (n = 505). The CIMT rate of each group was compared among 4 groups and the regression analysis was further used to correct confounders. RESULTS: We found that the NW-with NAFL group had a significantly higher CIMT rate than the AO-no NAFL group ([.87 ± .31] versus [.72 ± .29] P < .01) and the AO-with NAFL group ([.87 ± .31] versus [.79 ± .26], P < .01). CONCLUSIONS: The ectopic liver fat accumulation may increase the risk of atherosclerosis. Therefore, screening NAFLD in the population with normal weight may be beneficial for the prevention of atherosclerosis at an early stage.


Asunto(s)
Arterias Carótidas/diagnóstico por imagen , Grosor Intima-Media Carotídeo , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Obesidad Abdominal/diagnóstico por imagen , Tejido Adiposo/diagnóstico por imagen , Adulto , Aterosclerosis/diagnóstico por imagen , Composición Corporal , China , Femenino , Humanos , Hígado/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Análisis de Regresión , Factores de Riesgo
14.
Mediators Inflamm ; 2017: 3082805, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28255203

RESUMEN

Indirubin is a Chinese medicine extracted from indigo and known to be effective for treating chronic myelogenous leukemia, neoplasia, and inflammatory disease. This study evaluated the in vivo anti-inflammatory activity of indirubin in a lipopolysaccharide- (LPS-) induced mouse mastitis model. The indirubin mechanism and targets were evaluated in vitro in mouse mammary epithelial cells. In the mouse model, indirubin significantly attenuated the severity of inflammatory lesions, edema, inflammatory hyperemia, milk stasis and local tissue necrosis, and neutrophil infiltration. Indirubin significantly decreased myeloperoxidase activity and downregulated the production of tumor necrosis factor-α, interleukin-1ß (IL-1ß), and IL-6 caused by LPS. In vitro, indirubin inhibited LPS-stimulated expression of proinflammatory cytokines in a dose-dependent manner. It also downregulated LPS-induced toll-like receptor 4 (TLR4) expression and inhibited phosphorylation of LPS-induced nuclear transcription factor-kappa B (NF-κB) P65 protein and inhibitor of kappa B. In addition to its effect on the NF-κB signaling pathway, indirubin suppressed the mitogen-activated protein kinase (MAPK) signaling by inhibiting phosphorylation of extracellular signal-regulated kinase (ERK), P38, and c-jun NH2-terminal kinase (JNK). Indirubin improved LPS-induced mouse mastitis by suppressing TLR4 and downstream NF-κB and MAPK pathway inflammatory signals and might be a potential treatment of mastitis and other inflammatory diseases.


Asunto(s)
Lipopolisacáridos/toxicidad , Glándulas Mamarias Humanas/metabolismo , Mastitis/inducido químicamente , Mastitis/tratamiento farmacológico , Animales , Antiinflamatorios/uso terapéutico , Western Blotting , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Femenino , Factor Estimulante de Colonias de Granulocitos/metabolismo , Humanos , Indoles/uso terapéutico , Interleucina-1beta/metabolismo , Interleucina-3/metabolismo , Interleucina-6/metabolismo , Masculino , Glándulas Mamarias Humanas/citología , Glándulas Mamarias Humanas/patología , Mastitis/metabolismo , Ratones , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo
15.
J Neurochem ; 138(1): 163-73, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26991827

RESUMEN

The neurotrophin receptor p75 (p75NTR) is a receptor for amyloid-beta (Aß) and mediates Aß-induced neurodegenerative signals. The ectodomain of p75NTR (p75ECD) is a physiological protective factor against Aß in Alzheimer's disease (AD). We have previously demonstrated that the shedding of p75ECD from the cell surface is down-regulated in AD brains and restoration of the p75ECD level in the brain, through intracranial administration of p75ECD by adeno-associated virus vectors, attenuates AD-like pathologies in an AD mouse model. In this study, we further investigated the feasibility and efficacy of peripheral administration of AAV-p75ECD on brain amyloid burden and associated pathogenesis. We found that intramuscular delivery of AAV-p75ECD increased the level of p75ECD in the blood, significantly improved the behavioral phenotype of amyloid precursor protein/PS1 transgenic mice, and reduced brain amyloid burden, attenuated Tau hyperphosphorylation, and neuroinflammation. Furthermore, intramuscular delivery of AAV-p75ECD was well tolerated. Our results indicate that peripheral delivery of p75ECD represents a safe and effective therapeutic strategy for AD. The ectodomain of p75NTR (p75ECD) is a physiological protective factor against amyloid-beta (Aß) in Alzheimer's disease (AD). Intramuscular delivery of AAV-p75ECD increased the p75ECD levels in the blood, reduced brain amyloid burden through a 'peripheral sink' mechanism and alleviates AD-type pathologies. Peripheral delivery of p75ECD represents a promising therapeutic strategy for AD.


Asunto(s)
Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/terapia , Trastornos del Conocimiento/terapia , Receptor de Factor de Crecimiento Nervioso/química , Receptor de Factor de Crecimiento Nervioso/metabolismo , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animales , Trastornos del Conocimiento/genética , Dependovirus/genética , Modelos Animales de Enfermedad , Vectores Genéticos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Inyecciones Intramusculares , Aprendizaje por Laberinto/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación/genética , Presenilina-1/genética , Receptor de Factor de Crecimiento Nervioso/genética , Transducción Genética
16.
Hepatol Res ; 46(8): 784-93, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26609665

RESUMEN

AIM: Hepatocarcinogenesis is a multistep process from cirrhosis through low-grade dysplastic nodule, high-grade dysplastic nodule to hepatocellular carcinoma. Differential diagnosis between high-grade dysplastic nodules and early hepatocellular carcinomas is particularly difficult. The present study aims to identify a novel biological marker for differential diagnosis of the two lesions. METHODS: The expression level of an miRNA pair, miRNA-96-5p and 3p, was assessed by reverse transcription polymerase chain reaction in hepatic tissues. RESULTS: We showed that mature miRNA-96-5p and passenger strand miRNA-96-3p were differentially expressed in multistep hepatocarcinogenesis. miRNA-96-5p was significantly upregulated from cirrhosis, dysplastic nodules to hepatocellular carcinoma. However, significance of determination of miRNA-96-5p expression level for differential diagnosis between high-grade dysplastic nodule and hepatocellular carcinoma is limited. In contrast, the expression of miRNA-96-3p was detectable in cirrhosis and dysplastic nodules. Also, it was completely undetectable in the majority of hepatocellular carcinomas (30/34, 88.2%). The sensitivity and specificity of miRNA-96-3p negative expression for differential diagnosis of hepatocellular carcinomas from high-grade dysplastic nodules were 88.2% and 84.2%, respectively. In addition, a more specific diagnosis could be carried out by combining miRNA-96-3p with glypican 3, with the specificity of 100%. CONCLUSION: These findings demonstrated that miRNA-96-3p is a helpful diagnostic biomarker in differential diagnosis between high-grade dysplastic nodules and well-differentiated small hepatocellular carcinomas, especially in combination with glypican 3.

17.
J Chem Phys ; 145(16): 164314, 2016 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-27802659

RESUMEN

The excited-state orientation hydrogen-bonding dynamics, and vibronic spectra of isoquinoline (IQ) and its cationic form IQc in water have been investigated at the time-dependent density functional theory quantum chemistry level plus Franck-Condon simulation and interpretation. The excited-state orientation hydrogen bond strengthening has been found in IQ:H2O complex due to the charge redistribution upon excitation; this is interpreted by simulated 1:1 mixed absorption spectra of free IQ and IQ:H2O complex having best agreement with experimental results. Conversely, the orientation hydrogen bond in IQc:H2O complex would be strongly weakening in the S1 state and this is interpreted by simulated absorption spectra of free IQc having best agreement with experimental results. By performing Franck-Condon simulation, it reveals that several important vibrational normal modes with frequencies about 1250 cm-1 involving the wagging motion of the hydrogen atoms are very sensitive to the formation of the orientation hydrogen bond for the IQ/IQc:H2O complex and this is confirmed by damped Franck-Condon simulation with free IQ/IQc in water. However, the emission spectra of the IQ and IQc in water have been found differently. Upon the excitation, the simulated fluorescence of IQ in water is dominated by the IQ:H2O complex; thus hydrogen bond between IQ and H2O is much easier to form in the S1 state. While the weakened hydrogen bond in IQc:H2O complex is probably cleaved upon the laser pulse because the simulated emission spectrum of the free IQc is in better agreement with the experimental results.

18.
J Neuroinflammation ; 12: 153, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26311039

RESUMEN

BACKGROUND: Senile plaques consisting of amyloid-beta (Aß) are the major pathological hallmark of Alzheimer's disease (AD) and have been the primary therapeutic target. Immunotherapies, which are designed to remove brain Aß deposits, increased levels of soluble Aß and accelerated brain atrophy in some clinical trials, suggesting that the solubilization of Aß deposition might facilitate the formation of more toxic Aß oligomers and enhance neurotoxicity. METHODS: The capacity of antibodies against different epitopes of Aß to disaggregate preformed Aß fibrils was investigated. The co-incubation of antibodies and Aß fibrils was then tested for neurotoxicity both in vitro and in vivo. RESULTS: After the incubation of preformed Aß fibrils with the N-terminal antibody 6E10, the fibrils were decreased, while the oligomers, mostly dimers and trimers, were significantly increased. However, no such effects were observed for antibodies targeting the middle domain (4G8) and C-terminus of Aß (8G7). The co-incubates of preformed Aß fibrils with 6E10 were more neurotoxic, both in vitro and in vivo, than the co-incubates with 4G8 and 8G7. CONCLUSIONS: Our results indicate that the antibody targeting the N-terminus of Aß promoted the transformation of Aß from fibrils into oligomers and increased neurotoxicity. Immunotherapies should take into consideration the enhanced neurotoxicity associated with the solubilization of Aß deposits by antibodies against the Nterminus of Aß.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Anticuerpos/efectos adversos , Apoptosis/efectos de los fármacos , Síndromes de Neurotoxicidad , Fragmentos de Péptidos/inmunología , Péptidos beta-Amiloides/inmunología , Análisis de Varianza , Animales , Anticuerpos/uso terapéutico , Caspasa 3/metabolismo , Modelos Animales de Enfermedad , Humanos , Etiquetado Corte-Fin in Situ , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica de Transmisión , Neuritas/efectos de los fármacos , Neuritas/patología , Neuritas/ultraestructura , Síndromes de Neurotoxicidad/etiología , Síndromes de Neurotoxicidad/metabolismo , Síndromes de Neurotoxicidad/patología , Fragmentos de Péptidos/metabolismo , Fosfopiruvato Hidratasa/metabolismo , Placa Amiloide/patología
19.
Acta Neuropathol ; 130(4): 487-99, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26363791

RESUMEN

Amyloid-beta (Aß) plays a pivotal role in the pathogenesis of Alzheimer's disease (AD). The physiological capacity of peripheral tissues and organs in clearing brain-derived Aß and its therapeutic potential for AD remains largely unknown. Here, we measured blood Aß levels in different locations of the circulation in humans and mice, and used a parabiosis model to investigate the effect of peripheral Aß catabolism on AD pathogenesis. We found that blood Aß levels in the inferior/posterior vena cava were lower than that in the superior vena cava in both humans and mice. In addition, injected (125)I labeled Aß40 was located mostly in the liver, kidney, gastrointestinal tract, and skin but very little in the brain; suggesting that Aß derived from the brain can be cleared in the periphery. Parabiosis before and after Aß deposition in the brain significantly reduced brain Aß burden without alterations in the expression of amyloid precursor protein, Aß generating and degrading enzymes, Aß transport receptors, and AD-type pathologies including hyperphosphorylated tau, neuroinflammation, as well as neuronal degeneration and loss in the brains of parabiotic AD mice. Our study revealed that the peripheral system is potent in clearing brain Aß and preventing AD pathogenesis. The present work suggests that peripheral Aß clearance is a valid therapeutic approach for AD, and implies that deficits in the Aß clearance in the periphery might also contribute to AD pathogenesis.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Fragmentos de Péptidos/metabolismo , Adulto , Anciano , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Encéfalo/metabolismo , Encéfalo/patología , Modelos Animales de Enfermedad , Femenino , Humanos , Radioisótopos de Yodo , Masculino , Ratones Transgénicos , Persona de Mediana Edad , Presenilina-1/genética , Presenilina-1/metabolismo , Adulto Joven
20.
J Phys Chem A ; 119(24): 6269-74, 2015 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-26035309

RESUMEN

The dynamics of the excited-state intramolecular proton-transfer (ESIPT) reaction of quinoline-pyrazole (QP) isomers, designated as QP-I and QP-II, has been investigated by means of time-dependent density functional theory (TDDFT). A lower barrier has been found in the potential energy curve for the lowest singlet excited state (S1) along the proton-transfer coordinate of QP-II compared with that of QP-I; however, this is at variance with a recent experimental report [J. Phys. Chem. A 2010, 114, 7886-7891], in which the authors proposed that the ESIPT reaction would only proceed in QP-I due to the absence of a PT emission for QP-II. Therefore, several deactivating pathways have been investigated to determine whether fluorescence quenching occurs in the PT form of QP-II (PT-II). The S1 state of PT-II has nπ* character, which is a well-known dark state. Moreover, the energy gap between the S1 and T2 states is only 0.29 eV, implying that an intersystem crossing (ISC) process would occur rapidly following the ESIPT reaction. Therefore, it is demonstrated that the ESIPT could successfully proceed in QP-II and that the PT emission would be quenched by the ISC process.


Asunto(s)
Pirazoles/química , Quinolinas/química , Fluorescencia , Isomerismo , Modelos Químicos , Protones
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