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1.
Mol Neurobiol ; 60(11): 6676-6688, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37474884

RESUMO

Status epilepticus (SE) is a severe manifestation of epilepsy which can cause neurologic injury and death. This study aimed to identify key proteins involved in the pathogenesis of epilepsy and find a potential drug target for SE treatment. Tandem mass tag (TMT)-based quantitative proteomic analysis was applied to screen differentially expressed proteins (DEPs) in epilepsy. The adeno-associated virus was employed to overexpress candidate DEP in mice, and kainic acid (KA) was used to generate a mouse model of epilepsy. Then histopathological examination of the hippocampal tissue was performed, and the inflammatory factors levels in serum and hippocampus were measured. The IP-MS analysis was carried out to identify the interacting protein of nuclear cap-binding protein 1 (NCBP1). The results were that NCBP1 was downregulated in the epileptic hippocampus. NCBP1 overexpression alleviated KA-induced cognitive impairment in mice and reduced the apoptosis and damage of hippocampal neurons. Additionally, overexpressed NCBP1 increased the expression of NeuN and reduced the expression of GFAP and IBA-1 in the hippocampus of the mice. Further study indicated that NCBP1 overexpression inhibited the expression of IL-6, IL-1ß, and IFN-γ in serum and hippocampus as well as MDA and LDH in the hippocampus, whereas it increased the SOD levels, suggesting that overexpression of NCBP1 could diminish KA-induced inflammatory responses and oxidative stress. The IP-MS analysis identified that ELAVL4 was the NCBP1-interacting protein. In conclusion, this finding suggests that NCBP1 may potentially serve as a drug target for the treatment of epilepsy.

2.
Small ; 19(22): e2207822, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36866509

RESUMO

Uniformly depositing a thin layer of functional constituents on porous foam is attractive to realize their concentrated interfacial application. Here, a simple but robust polyvinyl alcohol (PVA)-mediated evaporation drying strategy to achieve uniform surface deposition on melamine foam (MF) is introduced. Solutes can be accumulated homogeneously to the surface periphery of MF due to the enhanced coffee-ring effect of PVA and its stabilizing effect on various functional constituents, including molecules and colloidal particles. The deposition thickness is positively correlated with the feeding amounts of PVA but seems to be independent of drying temperature. 3D outward capillary flow driven by the combination of contact surface pinning and continual interfacial evaporation induces the forming of core-shell foams. The enhanced interfacial photothermal effect and solar desalination performance using PVA/polypyrrole-coated MF as a Janus solar evaporator are demonstrated.

3.
Environ Pollut ; 322: 121200, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36736815

RESUMO

The alteration of agricultural wastes into novel adsorbents can stimulate their scalability in realistic application, showing great economic and environmental advantages. Here, we proposed a strategy to engineer rice husk (RH) with microporous melamine-formaldehyde networks (MFNs) resins and the utilization for dynamic removal of organic micropollutants rapidly and efficiently. was pre-treated to acquire attractive surface and unique hierarchical porosity, endowing with surface functionalization and essential filtering properties. MFNs can be uniformly generated in-situ on the fully exposed cellulose backbones of the pre-treated RH. MFNs granules functionalized RH (RH@MFNs) exhibited high removal efficiencies over 90% within 30 min for the adsorption of hazardous organic compounds (e.g., phenolic and antibiotic micropollutants) in static tests. Experiment results and density functional theory (DFT) simulation revealed that the synergy of hydrogen bonding, π-πinteraction, and micropore preservation dominates the adsorption. Further dynamic adsorption experiments showed that the removal efficiency and equilibrium removal capacity towards bisphenol A by RH@MFNs packed bed up-flow column were 2.6 and 67 times higher than that of raw RH, respectively. The column adsorption fits well with the Thomas model and bed depth service time (BDST) kinetic model. The inherent macropores inside RH and the roughness caused by the spiky structures and mesopores outside RH, as well as the accumulated MFNs granules, can lead to local turbulence of water flow around RH@MFNs, enabling fast and efficient adsorption. This sustainable and cost-effective preparation of RH-based adsorbents sheds light on the rational design of biomass waste adsorbents for realistic wastewater.


Assuntos
Oryza , Poluentes Químicos da Água , Purificação da Água , Purificação da Água/métodos , Oryza/química , Águas Residuárias , Polímeros , Formaldeído , Adsorção , Poluentes Químicos da Água/química
4.
Biol Trace Elem Res ; 201(9): 4497-4507, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36538210

RESUMO

To investigate fluoride (F)-induced intestine barrier damage and the role of estrogen deficiency in this progress, a rat model of estrogen deficiency was established through bilateral surgical removal of ovaries. The F exposure model was then continued by adding sodium fluoride (0, 25, 50, and 100 mg/L, calculated on a fluorine ion basis) to drinking water for 90 days. Afterward, intestinal mucosal structure, barrier function, and inflammatory cytokines were evaluated. The results showed that excessive F decreased the developmental parameters (crypt depth) of the cecum and rectum and inhibited the proliferation capacity of the intestinal epithelia, which are more obvious in the state of estrogen deficiency. The distribution of goblet cells and glycoproteins in the intestinal mucosa decreased with the increase in F concentration, and estrogen deficiency led to a further decline, especially in the rectum. Using the immunofluorescence method, the study showed that excessive F caused interleukin-17A (IL-17A) significantly decrease in the cecum and increase in the rectum. Meanwhile, F treatment remarkably upregulated the expression of intestinal IL-1ß, IL-23, and IL-22, while the level of IL-6 was downregulated. In addition, estrogen deficiency increased IL-1ß, IL-6, IL-23, and IL-22, but decreased IL-17A expression in the cecum and rectum. Collectively, F exposure damaged intestinal morphological structure, inhibited epithelial cell proliferation and mucus barrier function, and resulted in the disturbance of T helper (Th) 17 cell-related cytokines expression. Estrogen deficiency may further aggravate F-induced damage to the cecum and rectum.


Assuntos
Citocinas , Fluoretos , Animais , Ratos , Ceco/metabolismo , Citocinas/metabolismo , Estrogênios/farmacologia , Fluoretos/toxicidade , Interleucina-17/metabolismo , Interleucina-23 , Interleucina-6 , Mucosa Intestinal/metabolismo , Reto/metabolismo
5.
Ecotoxicol Environ Saf ; 246: 114181, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36252517

RESUMO

To investigate the effect of estrogen deficiency on the small intestinal mucosal barrier induced by fluoride (F), F exposure models of ovariectomy (OVX) rats (surgically removed ovaries) and non-OVX rats (normal condition) were established by adding sodium fluoride (NaF) (0, 25, 50, and 100 mg/L, calculated by F ion) in drinking water for 90 days. The intestinal mucosal histomorphology, mucosal barrier function, and protein expression levels of tight junctions (TJs), adhesion junctions (AJs), and desmosomes were evaluated in the duodenum, jejunum, and ileum. Hematoxylin-eosin (HE) staining and 5-Bromo-2-deoxyUridine (BrdU) measurement showed that excessive F-induced damage to intestinal epithelial cells and inhibited the proliferation of intestinal epithelial cells, eventually decreasing the number of goblet cells and decreasing glycoprotein secretion, as indicated by Alcian blue and periodic acid-Schiff (AB-PAS) and periodic acid-Schiff (PAS) staining. Further immunofluorescence analysis demonstrated that excessive F decreased the protein expression levels of occludin, zonula occludens-1 (ZO-1), E-cadherin, and desmoplakin (P < 0.05, P < 0.01) and enhanced the expression of claudin-2 (P < 0.01), suggesting that cell-to-cell junctions were disrupted. Collectively, F exposure impaired the small intestinal mucosal barrier by inducing damage to intestinal epithelial cells and inhibiting intestinal epithelial cell proliferation. Disorders in the junctional complex protein expression blocked the synergy between intercellular communication and aggravated mucosal injury. In particular, estrogen deficiency exacerbated F-induced enterotoxicity, which provides new explanations for the development and severity of intestinal disease in postmenopausal women with high-F areas.


Assuntos
Fluoretos , Mucosa Intestinal , Ratos , Feminino , Animais , Fluoretos/metabolismo , Ácido Periódico/metabolismo , Ácido Periódico/farmacologia , Mucosa Intestinal/metabolismo , Duodeno , Estrogênios/metabolismo
6.
J Hazard Mater ; 425: 127769, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-34799157

RESUMO

Both genetic damage and inappropriate immune function are relevant to cancer of hexavalent chromium [Cr(VI)]. However, its associations with immune response and genetic damage development are poorly understood. To explore their associations and mediating effects, 1249 participants were included from the Occupational Chromate Exposure Dynamic Cohort, and their blood Cr concentrations were measured as internal exposure. A set of biomarkers including urinary 8-hydroxy-2' - deoxyguanosine (8-OHdG), micronucleus frequency (MNF) and mitochondrial DNA copy number (mtCN) was developed to evaluate the landscape of genetic damage of Cr(VI). Serum C-reactive protein (CRP) and first component of complement q (C1q) were measured to reflect immune inflammation. Multivariate linear regression and mediation analyses were applied to assess the potential associations and mediation effects. It was found that blood Cr level showed significant dose-dependent relationships with increasing of MNF and urinary 8-OHdG, while negative association with CRP and C1q. Furthermore, a 1-unit increase in CRP was associated with decreases of - 0.765 to - 0.254 in MNF, - 0.400 to - 0.051 in urinary 8-OHdG. 4.97% of the association between blood Cr level and the increased MNF was mediated by CRP. 11.58% of the relationship between concentration of blood Cr and urinary 8-OHdG was mediated by C1q. These findings suggested that Cr(VI) exposures might prompt genetic damage, possibly partial via worsening immune inflammation.


Assuntos
Cromatos , Exposição Ocupacional , 8-Hidroxi-2'-Desoxiguanosina , Cromatos/toxicidade , Cromo/toxicidade , Dano ao DNA , Humanos , Inflamação/genética , Exposição Ocupacional/análise , Exposição Ocupacional/estatística & dados numéricos
7.
Int Immunopharmacol ; 73: 424-434, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31152980

RESUMO

Oxidized low density lipoprotein (ox-LDL) can induce the proliferation and differentiation of endothelial cells, which is one of the important mechanisms of ox-LDL atherosclerosis. Adiponectin is an endogenous bioactive polypeptide secreted by adipocytes, it participates in the metabolism of fat and glucose. It has the effect of reducing blood triglyceride and LDL content. Adiponectin also inhibits the abnormal proliferation and migration of endothelial cells, but its molecular mechanism is unclear. In this study, we used cell model of Ox-LDL-induced human aortic endothelial cells (HAECs) proliferation to analyze the molecular mechanism of APN inhibiting HAECs abnormal proliferation. The results showed that APN could inhibit the cell viability and DNA synthesis of HAECs after Ox-LDL treatment, up-regulate the apoptosis level and reduce the proportion of S + G2 phase cells. Further analysis showed that adiponectin could promote the dephosphorylation of Caveolin-1, which could dissociate eNOS and Caveolin-1, promote the phosphorylation of eNOS and enhance the synthesis of NO. NO increased expression levels of cleaved caspase 3 and p21 in the cells and inhibited the abnormal proliferation of HAECs. The regulation of phosphorylation and dephosphorylation of Caveolae-1 plays a key role in this process. Further study of the molecular mechanism of Caveolae-1 in the inhibition of HAECs abnormal proliferation by APN may reveal the potential of APN in the treatment of cardiovascular diseases.


Assuntos
Adiponectina/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Lipoproteínas LDL , Aorta , Caspase 3/metabolismo , Caveolina 1/metabolismo , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Células Endoteliais/metabolismo , Humanos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação/efeitos dos fármacos , Regulação para Cima
8.
J Radiat Res ; 60(4): 538-545, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31111948

RESUMO

The objective of this study was to build models to predict complete pathologic response (pCR) after neoadjuvant chemoradiotherapy (nCRT) in esophageal squamous cell carcinoma (ESCC) patients using radiomic features. A total of 55 consecutive patients pathologically diagnosed as having ESCC were included in this study. Patients were divided into a training cohort (44 patients) and a testing cohort (11 patients). The logistic regression analysis using likelihood ratio forward selection was performed to select the predictive clinical parameters for pCR, and the least absolute shrinkage and selection operator (LASSO) with logistic regression to select radiomic predictors in the training cohort. Model performance in the training and testing groups was evaluated using the area under the receiver operating characteristic curves (AUC). The multivariate logistic regression analysis identified no clinical predictors for pCR. Thus, only radiomic features selected by LASSO were used to build prediction models. Three logistic regression models for pCR prediction were developed in the training cohort, and they were able to predict pCR well in both the training (AUC, 0.84-0.86) and the testing cohorts (AUC, 0.71-0.79). There were no differences between these AUCs. We developed three predictive models for pCR after nCRT using radiomic parameters and they demonstrated good model performance.


Assuntos
Quimiorradioterapia Adjuvante , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/radioterapia , Adulto , Idoso , Neoplasias Esofágicas/diagnóstico por imagem , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Curva ROC , Análise de Regressão , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
9.
Anal Chem ; 91(10): 6836-6843, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31009572

RESUMO

Tumor-associated macrophages (TAMs) that exist in tumor microenvironment promote tumor progression and have been suggested as a promising therapeutic target for cancer therapy in preclinical studies. Development of theranostic systems capable of specific targeting, imaging, and ablation of TAMs will offer clinical benefits. Here we constructed a theranostic probe, namely, TPE-Man, by attaching mannose moieties to a red-emissive and AIE (aggregation-induced emission)-active photosensitizer. TPE-Man can specifically recognize a mannose receptor that is overexpressed on TAMs by the sugar-receptor interaction and enables fluorescent visualization of the mannose-receptor-positive TAMs in high contrast. The histologic study of mouse tumor sections further verifies TPE-Man's excellent targeting specificity being comparable with the commercial mannose-receptor antibody. TAMs can be effectively eradicated upon exposure to white light irradiation via a photodynamic therapy effect. To our knowledge, this is the first small molecular theranostic probe for TAMs that revealed combined advantages of low cost, high targeting specificity, fluorescent light-up imaging, and efficient photodynamic ablation.


Assuntos
Compostos de Benzilideno/farmacologia , Macrófagos/efeitos dos fármacos , Manosídeos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Animais , Compostos de Benzilideno/síntese química , Compostos de Benzilideno/efeitos da radiação , Compostos de Benzilideno/toxicidade , Manosídeos/síntese química , Manosídeos/efeitos da radiação , Manosídeos/toxicidade , Camundongos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/efeitos da radiação , Fármacos Fotossensibilizantes/toxicidade , Ratos Sprague-Dawley , Nanomedicina Teranóstica/métodos
10.
BMC Cancer ; 18(1): 575, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29776390

RESUMO

BACKGROUND: The objectives of this study were to build a normal tissue complication probability (NTCP) model of radiation-induced hypothyroidism (RHT) for nasopharyngeal carcinoma (NPC) patients and to compare it with other four published NTCP models to evaluate its efficacy. METHODS: Medical notes of 174 NPC patients after radiotherapy were reviewed. Biochemical hypothyroidism was defined as an elevated level of serum thyroid-stimulating hormone (TSH) value with a normal or decreased level of serum free thyroxine (fT4) after radiotherapy. Logistic regression with leave-one-out cross-validation was performed to establish the NTCP model. Model performance was evaluated and compared by the area under the receiver operating characteristic curve (AUC) in our NPC cohort. RESULTS: With a median follow-up of 24 months, 39 (22.4%) patients developed biochemical hypothyroidism. Gender, chemotherapy, the percentage thyroid volume receiving more than 50 Gy (V50), and the maximum dose of the pituitary (Pmax) were identified as the most predictive factors for RHT. A NTCP model based on these four parameters were developed. The model comparison was made in our NPC cohort and our NTCP model performed better in RHT prediction than the other four models. CONCLUSIONS: This study developed a four-variable NTCP model for biochemical hypothyroidism in NPC patients post-radiotherapy. Our NTCP model for RHT presents a high prediction capability. TRIAL REGISTRATION: This is a retrospective study without registration.


Assuntos
Hipotireoidismo/epidemiologia , Modelos Biológicos , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Lesões por Radiação/epidemiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Lesões por Radiação/sangue , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Estudos Retrospectivos , Fatores de Risco , Tireotropina/sangue , Tiroxina/sangue , Adulto Jovem
11.
RSC Adv ; 8(20): 10975-10979, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35541547

RESUMO

A theranostic drug delivery system composed of tetraphenyl-ethene (AIEgen), benzyl boronic ester (trigger), and doxorubicin (drug) was designed and synthesized; its utilities for cell imaging, drug delivery tracking, and cancer cell cytociding were evaluated.

12.
Mol Med Rep ; 16(1): 515-522, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28560462

RESUMO

Ischemic postconditioning has been demonstrated to alleviate brain ischemia/reperfusion-induced neuronal apoptosis; however, the protective mechanisms underlying the improved and more convenient method of remote ischemic postconditioning (RIPostC) are only recently beginning to be elucidated. Mitochondria are important in the regulation of cell apoptosis, and the B­cell lymphoma 2 (Bcl­2) homology 3 interacting­domain death agonist (BID) promotes the insertion/oligomerization of Bcl­2­associated X protein into the mitochondrial outer membrane, leading to the release of proapoptotic proteins from the mitochondria. The present study hypothesized that RIPostC targets the BID­mediated mitochondrial apoptotic pathway to exert neuroprotective effects, and the optimal time window for RIPostC application was investigated. RIPostC was conducted as follows: Three 10­min cycles of bilateral femoral artery occlusion with intervals of 10 min reperfusion after 0, 10 or 30 min of brain reperfusion. The results revealed that reperfusion induced significant activation of BID, via proteolytic cleavage and translocation to the mitochondria, as determined using western blot analysis and immunofluorescence staining. Mitochondrial release of cytochrome c was additionally detected during BID activation, all of which were inhibited by the application of RIPostC. When RIPostC was applied during reperfusion, it demonstrated a significant protective effect. Furthermore, the infarct volume, neurological function and the degree of neuronal apoptosis were improved with application of RIPostC. These results suggested that the protective mechanisms of RIPostC may be associated with inhibition of the BID­mediated mitochondrial apoptotic pathway, which may act as a potential molecular target for therapeutic intervention in the future.


Assuntos
Apoptose , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Pós-Condicionamento Isquêmico , Mitocôndrias/metabolismo , Neurônios/metabolismo , Transdução de Sinais , Animais , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/genética , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Citocromos c/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Masculino , Transporte Proteico , Ratos
13.
Chem Commun (Camb) ; 53(10): 1653-1656, 2017 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-28098271

RESUMO

A two-channel responsive and AIE-active fluorescent probe was developed to selectively detect superoxide anions in living cells, which can be used to track the endogenous superoxide anion level when cells undergo apoptosis and inflammation.


Assuntos
Corantes Fluorescentes/química , Superóxidos/análise , Ânions/análise , Apoptose , Sobrevivência Celular , Corantes Fluorescentes/síntese química , Células Hep G2 , Humanos , Inflamação , Estrutura Molecular
14.
J Immunol Methods ; 424: 91-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26009247

RESUMO

During drug development, measurement of suitable pharmacodynamic biomarkers is key to establishing in vivo drug activity. Binding of monoclonal antibody (mAb) therapeutics to soluble target proteins often results in elevated serum levels of their target antigen, and measuring total (free and bound) concentration of the target antigen can be an important means of demonstrating that the mAb has reached its specific target. However, accurately measuring soluble circulating antigen in preclinical or clinical samples in the presence of a therapeutic mAb presents a bioanalytical challenge. Particularly in the case of low molecular weight and/or multimeric targets, epitopes for capture and detection of the target by reagent antibodies can be obscured by bound therapeutic mAb. Lymphotoxin-alpha (LTα) is a cytokine in the TNF superfamily that has been implicated in the pathophysiology of autoimmune disease, and is a therapeutic target for neutralizing mAb. During preclinical safety studies in cynomolgus macaques, we encountered difficulties in measuring total LTα in serum of dosed animals. When serum LTα trimer was saturated with the anti-LTα mAb, binding of two reagent antibodies, as required for a classic sandwich ELISA, was not feasible, and dissociation methods were also found to be unsuitable. We therefore developed an approach in which excess anti-LTα mAb was added to the in vitro assay system to fully saturate all binding sites, and an anti-idiotypic antibody was used to detect bound therapeutic antibody. Using this method, total LTα could be accurately measured in cynomolgus macaque serum, and was observed to increase with increasing anti-LTα therapeutic mAb dose. Additional in vitro studies demonstrated that the method worked equally well in human serum. This assay strategy will be useful for quantifying total concentrations of other small and/or multimeric target proteins in the presence of a therapeutic antibody.


Assuntos
Anticorpos Monoclonais/farmacocinética , Imunoensaio/métodos , Linfotoxina-alfa/sangue , Animais , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Anti-Idiotípicos/farmacologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Monoclonais Humanizados/farmacocinética , Humanos , Ligantes , Linfotoxina-alfa/imunologia , Macaca fascicularis , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Anal Chem ; 84(16): 7112-23, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22794164

RESUMO

The heterogeneity in therapeutic antibodies arising from buried unpaired cysteines has not been well studied. This paper describes the characterization of two unpaired cysteines in a recombinant humanized IgG1 monoclonal antibody (referred to as mAb A). The reversed-phase high-performance liquid chromatography (RP-HPLC) analysis of mAb A samples showed three distinct peaks, indicating the presence of three species. The heterogeneities observed in the RP-HPLC have been determined to arise from unpaired cysteines (Cys-22 and Cys-96) that are buried in the V(H) domain. The Fab containing free thiols (referred to as "free-thiol Fab") and the Fab containing the disulfide (referred to as "intact Fab") of mAb A were generated through limited Lys-C digestion and purified with an ion exchange chromatography method. The binding of free-thiol Fab and intact Fab to its antigen was measured in a cell-based binding assay and an enzyme linked immunosorbent assay. The unpaired cysteines in the Fab of mAb A were found to have no significant impact on the binding to its target. Consistent with these Fab binding data, the enriched intact mAb A containing free thiols was determined to be fully active in a potency assay. The data reported here demonstrate that the redox status of cysteines is potentially a major source of heterogeneity for an antibody.


Assuntos
Anticorpos Monoclonais/química , Cisteína , Imunoglobulina G/química , Proteínas Recombinantes/química , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/toxicidade , Antígenos CD20/imunologia , Células CHO , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Cromatografia de Fase Reversa , Cricetinae , Cricetulus , Humanos , Imunoglobulina G/imunologia , Imunoglobulina G/toxicidade , Espectrometria de Massas , Desnaturação Proteica , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/toxicidade , Compostos de Sulfidrila/química
16.
J Neurochem ; 109(4): 1067-78, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19519778

RESUMO

Insertional mutations in exon 4 of the ferritin light chain (FTL) gene are associated with hereditary ferritinopathy (HF) or neuroferritinopathy, an autosomal dominant neurodegenerative disease characterized by progressive impairment of motor and cognitive functions. To determine the pathogenic mechanisms by which mutations in FTL lead to neurodegeneration, we investigated iron metabolism and markers of oxidative stress in the brain of transgenic (Tg) mice that express the mutant human FTL498-499InsTC cDNA. Compared with wild-type mice, brain extracts from Tg (FTL-Tg) mice showed an increase in the cytoplasmic levels of both FTL and ferritin heavy chain polypeptides, a decrease in the protein and mRNA levels of transferrin receptor-1, and a significant increase in iron levels. Transgenic mice also showed the presence of markers for lipid peroxidation, protein carbonyls, and nitrone-protein adducts in the brain. However, gene expression analysis of iron management proteins in the liver of Tg mice indicates that the FTL-Tg mouse liver is iron deficient. Our data suggest that disruption of iron metabolism in the brain has a primary role in the process of neurodegeneration in HF and that the pathogenesis of HF is likely to result from a combination of reduction in iron storage function and enhanced toxicity associated with iron-induced ferritin aggregates in the brain.


Assuntos
Apoferritinas/genética , Apoferritinas/fisiologia , Distúrbios do Metabolismo do Ferro/genética , Distúrbios do Metabolismo do Ferro/metabolismo , Ferro/metabolismo , Estresse Oxidativo/genética , Animais , Química Encefálica/fisiologia , Ensaio de Desvio de Mobilidade Eletroforética , Éxons/genética , Homeostase/genética , Homeostase/fisiologia , Imuno-Histoquímica , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ferroproteínas não Heme/metabolismo
17.
Mod Pathol ; 21(8): 950-60, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18500269

RESUMO

Detection of lung cancer by sputum cytology has low sensitivity but is noninvasive and, if improved, could be a powerful tool for early lung cancer detection. To evaluate whether the accuracy of diagnosing lung cancer by evaluating sputa for cytologic atypia and genetic abnormalities is greater than that of conventional cytology alone, automated scoring of genetic abnormalities for 3p22.1 and 10q22.3 (SP-A) by fluorescence in situ hybridization (FISH) and conventional cytology was done on sputa from 35 subjects with lung cancer, 25 high-risk smokers, and 6 healthy control subjects. Multivariate analysis was performed to select variables that most accurately predicted lung cancer. A model of probability for the presence of lung cancer was derived for each subject. Cells exfoliated from patients with lung cancer contained genetic aberrations and cytologic atypias at significantly higher levels than in those from control subjects. When combined with cytologic atypia, a model of risk for lung cancer was derived that had 74% sensitivity and 82% specificity to predict the presence of lung cancer, whereas conventional cytology achieved only 37% sensitivity and 87% specificity. For diagnosing lung cancer in sputum, a combination of molecular and cytologic variables was superior to using conventional cytology alone.


Assuntos
Carcinoma Neuroendócrino/genética , Carcinoma de Células Escamosas/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 3 , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Neuroendócrino/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Citodiagnóstico/métodos , Feminino , Humanos , Citometria por Imagem/métodos , Hibridização in Situ Fluorescente/métodos , Neoplasias Pulmonares , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Escarro/citologia
18.
J Neurosci ; 28(1): 60-7, 2008 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-18171923

RESUMO

Increased iron levels and iron-mediated oxidative stress play an important role in the pathogenesis of many neurodegenerative diseases. The finding that mutations in the ferritin light polypeptide (FTL) gene cause a neurodegenerative disease known as neuroferritinopathy or hereditary ferritinopathy (HF) provided a direct connection between abnormal brain iron storage and neurodegeneration. HF is characterized by a severe movement disorder and by the presence of nuclear and cytoplasmic ferritin inclusion bodies in glia and neurons throughout the CNS and in tissues of multiple organ systems. Here we report that the expression in transgenic mice of a human FTL cDNA carrying a thymidine and cytidine insertion at position 498 (FTL498-499InsTC) leads to the formation of nuclear and cytoplasmic ferritin inclusion bodies. As in HF, ferritin inclusions are seen in glia and neurons throughout the CNS as well as in cells of other organ systems. Our studies show histological, immunohistochemical, and biochemical similarities between ferritin inclusion bodies found in transgenic mice and in individuals with HF. Expression of the transgene in mice leads to a significant decrease in motor performance and a shorter life span, formation of ferritin inclusion bodies, misregulation of iron metabolism, accumulation of ubiquitinated proteins, and incorporation of elements of the proteasome into inclusions. This new transgenic mouse represents a relevant model of HF in which to study the pathways that lead to neurodegeneration in HF, to evaluate the role of iron mismanagement in neurodegenerative disorders, and to evaluate potential therapies for HF and related neurodegenerative diseases.


Assuntos
Ferritinas/genética , Expressão Gênica/genética , Sobrecarga de Ferro/genética , Mutação/genética , Doenças Neurodegenerativas/genética , Animais , Apoferritinas , Comportamento Animal , Encéfalo/patologia , Encéfalo/ultraestrutura , Modelos Animais de Doenças , Humanos , Ferro/metabolismo , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Sobrecarga de Ferro/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão/métodos , Atividade Motora/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/fisiopatologia
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