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1.
World J Surg Oncol ; 22(1): 148, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840176

RESUMO

BACKGROUND: Gasless transaxillary endoscopic thyroidectomy (GTET) and endoscopic thyroidectomy via the areola approach (ETA) have emerged as minimally invasive surgical techniques for managing papillary thyroid carcinoma (PTC). This study aimed to assess the surgical efficacy of endoscopic thyroidectomy (ET) as compared to conventional open thyroidectomy (COT) in PTC patients. METHODS: Between 2020 and 2022, 571 PTC patients underwent unilateral thyroidectomy accompanied by ipsilateral central lymph node dissection. This cohort comprised 72 patients who underwent GTET, 105 ETA, and 394 COT. The analysis encompassed a comprehensive examination of patient clinicopathologic characteristics and postoperative complaints. Furthermore, the learning curve of GTET was evaluated using the cumulative summation (CUSUM) method. RESULTS: Patients in the ET group exhibited a lower mean age and a higher proportion of female individuals. Operation time in the ET group was significantly longer. No significant differences were observed in the incidence of postoperative complications among the three groups. With regard to postoperative complaints reported three months after surgery, GTET demonstrated superior alleviation of anterior chest discomfort and swallowing difficulties. Patients who underwent ET reported significantly higher cosmetic satisfaction levels. Additionally, the learning curve of GTET was 27 cases, and the operation time during the mature phase of the learning curve exhibited a significant reduction when compared to ETA. CONCLUSIONS: The findings of this study affirm the safety and feasibility of employing GTET and ETA for the surgical management of PTC. GTET presents an attractive surgical option, particularly for patients with unilateral PTC who place a premium on cosmetic outcomes.


Assuntos
Endoscopia , Complicações Pós-Operatórias , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Tireoidectomia , Humanos , Tireoidectomia/métodos , Tireoidectomia/efeitos adversos , Feminino , Masculino , Câncer Papilífero da Tireoide/cirurgia , Câncer Papilífero da Tireoide/patologia , Endoscopia/métodos , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Pessoa de Meia-Idade , Adulto , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Seguimentos , Estudos Retrospectivos , Prognóstico , Duração da Cirurgia , Axila
2.
Anal Chem ; 95(26): 9990-9998, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37350101

RESUMO

In this work, a novel plasmonic heterodimer with controllable hot spot was designed and applied to regulate surface plasmon coupling electrochemiluminescence (SPC-ECL) polarization sensing system. The heterodimer nanostructure consisted of individual Au-Ag core-shell nanocubes (Au@Ag NC) and Au nanospheres (Au NS), which were precisely assembled by thiol-DNA and biotin-streptavidin. The asymmetric nanostructure can significantly modulate the ECL intensity and emission polarization angle based on the synergy of the surface plasmon coupling (SPC) effect and the lightning rod effect with extraordinary field enhancement in the hot spot region. As a result, the isotropic ECL signal of zinc-doped nitrogen dots (Zn-N dots) was regulated in the directional emission. Furthermore, the SPC-ECL biosensor was successfully applied to detect miRNA-182 in triple-negative breast cancer (TNBC) tissues. The research on the established relationship between ECL polarization analysis and plasmonic heterodimers can provide a new pathway for the development of ECL sensing platforms.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , Pontos Quânticos , Medições Luminescentes , Pontos Quânticos/química , Ouro/química , Técnicas Eletroquímicas , MicroRNAs/análise , Nanopartículas Metálicas/química , Limite de Detecção
3.
Mikrochim Acta ; 190(8): 325, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37493765

RESUMO

A cost-effective approach has been developed to synthesize Cu nanoparticles encapsulated into B and N double-doped carbon nanotubes (Cu@BCNNTs) by one-step pyrolysis. According to the specific binding of Cu-Cl and Cu-glutathione (GSH), we employed Cu@BCNNTs to build an electrochemical sensing platform to detect GSH. The unique space-confined structure can prevent Cu nanoparticles from agglomeration. In addition, B and N co-doped porous hollow tubes can improve the electrochemical conductivity, expand the number of active sites, enhance surface adsorption, and shorten the transport path. These favorable characteristics of Cu@BCNNTs make them have excellent electrocatalytic properties. These results display that the prepared sensor can detect GSH from 0.5 to 120 µM with a detection limit of 0.024 µM. The obtained sensors can be successfully applied in the human serum with recovery of GSH ranging from 100.2 to 103.9%. This work provides a new vision to synthesize nanoparticles confined in a hollow tube for the applications in biosensing and medical diagnostics.


Assuntos
Técnicas Biossensoriais , Nanopartículas , Nanotubos de Carbono , Humanos , Nanotubos de Carbono/química , Porosidade , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Eletrodos , Nanopartículas/química , Glutationa , Nanotecnologia
4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(1): 57-63, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36861156

RESUMO

Objective To evaluate the performance of contrast-enhanced ultrasound (CEUS) liver imaging reporting and data system (LI-RADS) LR-5 in the diagnosis of hepatocellular carcinoma (HCC). Methods The clinical research reports with the application of CEUS LI-RADS in the diagnosis of HCC were collected from PubMed,Embase,Cochrane Library,CNKI,and Wanfang Data from inception to November 14,2021.Two researchers respectively screened the literature and extracted relevant information.The Quality Assessment of Diagnostic Accuracy Studies (QUADAS) was used to evaluate the quality of all the included articles.RevMan 5.4,Meta disc 1.4,and Stata 16.0 were employed to analyze the diagnostic performance of LR-5 for HCC in high-risk patients. Results Twenty original studies were included,involving a total of 6131 lesions,of which 5142 were HCC.The results of meta-analysis showed that the LR-5 in CEUS LI-RADS for diagnosing HCC in the high-risk population had the overall sensitivity of 0.72 (95%CI=0.66-0.77),the overall specificity of 0.93 (95%CI=0.87-0.96),the overall positive likelihood ratio of 9.89 (95%CI=5.31-18.41),the overall negative likelihood ratio of 0.30 (95%CI=0.25-0.37),and the area under the summary receiver operating characteristic curve of 0.88 (95%CI=0.85-0.91).There was heterogeneity among the included studies (I2=95.31,P<0.001).The funnel plot indicated the existence of publication bias (P=0.04). Conclusion The CEUS LI-RADS can effectively diagnose HCC in high-risk patients based on the LR-5 criteria.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Diagnóstico por Imagem , Ultrassonografia
5.
Allergy ; 76(8): 2475-2487, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33378582

RESUMO

BACKGROUND: Asthma is characterized by airway hyperresponsiveness (AHR), inflammation, and airway remodeling. Airway hyperresponsiveness results from enhanced airway smooth muscle (ASM) contraction potentially under the control of an epithelium-derived relaxing factor (EpDRF). However, relatively rare is known about EpDRF. We aimed to elucidate the role of epithelium-derived stanniocalcin-1 (STC1) on AHR and ASM contraction. METHODS: Stanniocalcin-1 levels in the serum of asthmatic patients and healthy volunteers and in bronchoalveolar lavage fluid (BALF) from ovalbumin (OVA)-challenged mice were measured by ELISA. The effects of exogenous STC1 on AHR and on inflammation were examined in mice. IL-13 modulation of STC1 mRNA and protein levels was studied in human bronchial epithelial cell lines (16HBE). The function of STC1 on Ca2+ influx and ASM contraction was examined ex vivo. RESULTS: Serum STC1 was decreased in asthma (n = 93) compared with healthy volunteers (1071 ± 30.4 vs 1414 ± 75.1 pg/ml, p < 0.0001, n = 23) and correlated with asthma control (p = 0.0270), lung function (FEV1, p = 0.0130), and serum IL-13 levels (p = 0.0009). Treatment of ten asthmatic subjects with inhaled corticosteroids/long-acting beta2-agonists (ICS/LABA) for 1 year enhanced STC1 expression which correlated with improved asthma control (p = 0.022). STC1 was mainly expressed in bronchial epithelium and intranasal administration of recombinant human STC1 (rhSTC1) reduced AHR and inflammation in mice. IL-13 suppressed STC1 release from 16HBE, whereas rhSTC1 blocked store-operated Ca2+ entry (SOCE) by suppressing stromal interaction molecule 1 (STIM1) and further inhibited ASM cell contractility by suppressing Ca2+ -dependent myosin light chain (MLC) phosphorylation. CONCLUSION: Our data indicate that STC1 deficiency in asthmatic airways promotes STIM1 hyperactivity, enhanced ASM contraction, and AHR. STC1 may be a candidate EpDRF.


Assuntos
Asma , Hipersensibilidade Respiratória , Animais , Asma/tratamento farmacológico , Brônquios , Líquido da Lavagem Broncoalveolar , Canais de Cálcio , Glicoproteínas , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina
6.
Biol Blood Marrow Transplant ; 26(1): 94-106, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31493539

RESUMO

Allogeneic blood or marrow transplantation (BMT) is a potentially curative therapy for patients with primary immunodeficiency (PID). Safe and effective reduced-intensity conditioning (RIC) approaches that are associated with low toxicity, use alternative donors, and afford good immune reconstitution are needed to advance the field. Twenty PID patients, ranging in age from 4 to 58 years, were treated on a prospective clinical trial of a novel, radiation-free and serotherapy-free RIC, T-cell-replete BMT approach using pentostatin, low-dose cyclophosphamide, and busulfan for conditioning with post-transplantation cyclophosphamide-based graft-versus-host-disease (GVHD) prophylaxis. This was a high-risk cohort with a median hematopoietic cell transplantation comorbidity index of 3. With median follow-up of survivors of 1.9 years, 1-year overall survival was 90% and grade III to IV acute GVHD-free, graft-failure-free survival was 80% at day +180. Graft failure incidence was 10%. Split chimerism was frequently observed at early post-BMT timepoints, with a lower percentage of donor T cells, which gradually increased by day +60. The cumulative incidences of grade II to IV and grade III to IV acute GVHD (aGVHD) were 15% and 5%, respectively. All aGVHD was steroid responsive. No patients developed chronic GVHD. Few significant organ toxicities were observed. Evidence of phenotype reversal was observed for all engrafted patients, even those with significantly mixed chimerism (n = 2) or with unknown underlying genetic defect (n = 3). All 6 patients with pre-BMT malignancies or lymphoproliferative disorders remain in remission. Most patients have discontinued immunoglobulin replacement. All survivors are off immunosuppression for GVHD prophylaxis or treatment. This novel RIC BMT approach for patients with PID has yielded promising results, even for high-risk patients.


Assuntos
Transplante de Medula Óssea , Bussulfano/administração & dosagem , Ciclofosfamida/administração & dosagem , Doença Enxerto-Hospedeiro , Pentostatina/administração & dosagem , Condicionamento Pré-Transplante , Adolescente , Adulto , Bussulfano/efeitos adversos , Criança , Pré-Escolar , Ciclofosfamida/efeitos adversos , Intervalo Livre de Doença , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Transfusão de Linfócitos , Masculino , Pessoa de Meia-Idade , Pentostatina/efeitos adversos , Doenças da Imunodeficiência Primária/mortalidade , Doenças da Imunodeficiência Primária/terapia , Estudos Prospectivos , Taxa de Sobrevida
7.
Anal Chem ; 92(23): 15297-15305, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33185440

RESUMO

Oxidative stress is a state of stress injury, which leads to the pathogenesis of most neurodegenerative diseases. Moreover, this is also one of the main reasons for the loss of dopaminergic neurons and the abnormal content of dopamine (DA). In the past decades, a number of studies have found that acetaminophen (AP) is metabolized and distributed in the brain when it is used as a neuroprotective compound. In this context, we proposed an electrochemical sensor based on 9-(4-(10-phenylanthracen-9-yl)phenyl)-9H-carbazole with the goal of diagnosing these two drugs in the body. Carbazole groups can easily be formed into large π-conjugated systems by electropolymerization. The introduction of anthracene exactly combined the carbazole group to establish an efficient electron donor-acceptor pattern, which enhanced π-π interaction with the electrode surface and charge transporting ability. The diagnostic platform showed good sensing activity toward the oxidation of DA and AP. The detection range for DA and AP is from 0.2 to 300 µM and from 0.2 to 400 µM, respectively. The simultaneous detection range is from 0.5 to 250 µM, which is wider than most reports. After a series of electrochemical assessments were determined, the sensor was finally developed to the analysis of pharmaceutical and human serum, displaying a meaningful potential in clinical evaluation.


Assuntos
Teoria da Densidade Funcional , Eletroquímica/métodos , Acetaminofen/análise , Acetaminofen/sangue , Acetaminofen/química , Dopamina/análise , Dopamina/sangue , Dopamina/química , Eletroquímica/instrumentação , Eletrodos , Humanos , Modelos Moleculares , Conformação Molecular , Oxirredução , Polimerização
8.
Plant Physiol ; 181(2): 743-761, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31350362

RESUMO

Plants cope with aluminum (Al) toxicity by secreting organic acids (OAs) into the apoplastic space, which is driven by proton (H+) pumps. Here, we show that mutation of vacuolar H+-translocating adenosine triphosphatase (H+-ATPase) subunit a2 (VHA-a2) and VHA-a3 of the vacuolar H+-ATPase enhances Al resistance in Arabidopsis (Arabidopsis thaliana). vha-a2 vha-a3 mutant plants displayed less Al sensitivity with less Al accumulation in roots compared to wild-type plants when grown under excessive Al3+ Interestingly, in response to Al3+ exposure, plants showed decreased vacuolar H+ pump activity and reduced expression of VHA-a2 and VHA-a3, which were accompanied by increased plasma membrane H+ pump (PM H+-ATPase) activity. Genetic analysis of plants with altered PM H+-ATPase activity established a correlation between Al-induced increase in PM H+-ATPase activity and enhanced Al resistance in vha-a2 vha-a3 plants. We determined that external OAs, such as malate and citrate whose secretion is driven by PM H+-ATPase, increased with PM H+-ATPase activity upon Al stress. On the other hand, elevated secretion of malate and citrate in vha-a2 vha-a3 root exudates appeared to be independent of OAs metabolism and tolerance of phosphate starvation but was likely related to impaired vacuolar sequestration. These results suggest that coordination of vacuolar H+-ATPase and PM H+-ATPase dictates the distribution of OAs into either the vacuolar lumen or the apoplastic space that, in turn, determines Al tolerance capacity in plants.


Assuntos
Alumínio/toxicidade , Arabidopsis/metabolismo , Ácidos Carboxílicos/metabolismo , Raízes de Plantas/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Alumínio/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Pirofosfatase Inorgânica/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Raízes de Plantas/efeitos dos fármacos , ATPases Vacuolares Próton-Translocadoras/genética
9.
Cancer Cell Int ; 20(1): 585, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33372610

RESUMO

RNA methylation has emerged as a fundamental process in epigenetic regulation. Accumulating evidences indicate that RNA methylation is essential for many biological functions, and its dysregulation is associated with human cancer progression, particularly in gastrointestinal cancers. RNA methylation has a variety of biological properties, including N6-methyladenosine (m6A), 2-O-dimethyladenosine (m6Am), N1-methyladenosine (m1A), 5-methylcytosine (m5C) and 7-methyl guanosine (m7G). Dynamic and reversible methylation on RNA is mediated by RNA modifying proteins called "writers" (methyltransferases) and "erasers" (demethylases). "Readers" (modified RNA binding proteins) recognize and bind to RNA methylation sites, which influence the splicing, stability or translation of modified RNAs. Herein, we summarize the biological functions and mechanisms of these well-known RNA methylations, especially focusing on the roles of m6A in gastrointestinal cancer development.

10.
Cell Mol Life Sci ; 76(2): 381-395, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30368549

RESUMO

Sister chromatid cohesion plays a key role in ensuring precise chromosome segregation during mitosis, which is mediated by the multisubunit cohesin complex. However, the molecular regulation of cohesin subunits stability remains unclear. Here, we show that NudCL2 (NudC-like protein 2) is essential for the stability of cohesin subunits by regulating Hsp90 ATPase activity in mammalian cells. Depletion of NudCL2 induces mitotic defects and premature sister chromatid separation and destabilizes cohesin subunits that interact with NudCL2. Similar defects are also observed upon inhibition of Hsp90 ATPase activity. Interestingly, ectopic expression of Hsp90 efficiently rescues the protein instability and functional deficiency of cohesin induced by NudCL2 depletion, but not vice versa. Moreover, NudCL2 not only binds to Hsp90, but also significantly modulates Hsp90 ATPase activity and promotes the chaperone function of Hsp90. Taken together, these data suggest that NudCL2 is a previously undescribed Hsp90 cochaperone to modulate sister chromatid cohesion by stabilizing cohesin subunits, providing a hitherto unrecognized mechanism that is crucial for faithful chromosome segregation during mitosis.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Cromátides/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/genética , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Proteínas de Ligação a DNA , Células HEK293 , Proteínas de Choque Térmico HSP90/genética , Células HeLa , Humanos , Microscopia de Fluorescência , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Estabilidade Proteica , Subunidades Proteicas/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Imagem com Lapso de Tempo , Coesinas , Quinase 1 Polo-Like
11.
Am J Respir Crit Care Med ; 199(4): 496-507, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30290132

RESUMO

RATIONALE: Bronchial epithelial cell damage occurs in patients with bronchial asthma. Ezrin, a membrane-cytoskeleton protein, maintains cellular morphology and intercellular adhesion and protects the barrier function of epithelial cells. OBJECTIVES: To study the role of ezrin in bronchial epithelial cells injury and correlate its expression with asthma severity. METHODS: Levels of ezrin were measured in exhaled breath condensate (EBC) and serum in patients with asthma and BAL fluid (BALF) from a mouse model of asthma by ELISA. The regulation of IL-13 on ezrin protein levels was studied in primary bronchial epithelial cells. Ezrin knockdown using shRNA was studied in human bronchial epithelial 16HBE cells. MEASUREMENTS AND MAIN RESULTS: Ezrin levels were decreased in asthmatic EBC (92.7 ± 34.99 vs. 150.5 ± 10.22 pg/ml, P < 0.0001) and serum (700.7 ± 55.59 vs. 279.2 ± 25.83 pg/ml, P < 0.0001) compared with normal subjects. Levels were much lower in uncontrolled (P < 0.001) and partly controlled patients (P < 0.01) compared with well-controlled subjects. EBC and serum ezrin levels correlated with lung function in patients with asthma and serum ezrin levels were negatively correlated with serum IL-13 and periostin. IL-13-induced downregulation of ezrin expression in primary bronchial epithelial cells was significantly attenuated by the Janus tyrosine kinase 2 inhibitor, TG101348. Ezrin knockdown changed 16HBE cell morphology, enlarged intercellular spaces, and increased their permeability. Ezrin expression was decreased in the lung tissue and BALF of "asthmatic" mice and negatively correlated with BALF IL-13 level. CONCLUSIONS: Ezrin downregulation is associated with IL-13-induced epithelial damage and might be a potential biomarker of asthma control.


Assuntos
Asma/patologia , Proteínas do Citoesqueleto/análise , Mucosa Respiratória/patologia , Animais , Asma/sangue , Biomarcadores/análise , Biomarcadores/sangue , Brônquios/patologia , Líquido da Lavagem Broncoalveolar/química , Estudos de Casos e Controles , Moléculas de Adesão Celular/sangue , Proteínas do Citoesqueleto/sangue , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucina-13/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Testes de Função Respiratória
12.
Mikrochim Acta ; 187(3): 163, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32052190

RESUMO

An electrochemical aptasensor for thrombin is introduced that makes use of a nanohybrid composed of silver nanoparticles and graphite-like carbon nitride (Ag-g-C3N4). The material has a large surface and good biocompatibility. AgNPs are modified directly on the surface of g-C3N4 via chemical reduction. A glass carbon electrode (GCE) modified with Ag-g-C3N4 can immobilize a large number of amino-terminated thrombin binding aptamers (NH2-TBA) through strong Ag-N bonds. The electrochemical impedance signal of the aptasensor increases in the presence of thrombin. Under the optimal conditions and by using [Fe(CN)6]3-/4- as an electrochemical probe, the aptasensor shows a wide linear range of 100 fM - 20 nM with a lower detection limit of 38 fM. The method was applied to the determination of thrombin in spiked human plasma and the recoveries fluctuated from 97.2% to 103%. Graphical abstractSchematic representation of an electrochemical aptasensor using graphite-like carbon nitride (C3N4) modified with silver nanoparticles as electrode substrate for thrombin (TB) detection.


Assuntos
Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , Prata/química , Trombina/química , Humanos
13.
Anal Chem ; 91(16): 10589-10595, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31333020

RESUMO

Here, we report ZIF-8-reduced graphene oxide (ZIF-8-rGO)-supported bimetallic AuPt nanoparticles (AuPtNPs) as a novel peroxidase mimic for high-sensitivity detection of H2O2 in neutral solution. ZIF-8-graphene oxide (ZIF-8-GO) is first synthesized via a simple wet-chemistry process and subsequently immobilized with AuPtNPs via a reduction method. The resultant AuPt/ZIF-8-rGO shows enhanced peroxidase-like catalytic activity and it is applied for the electrochemical detection of H2O2 in a wide concentration range, from 100 nM to 18 mM, with a very low detection limit of 19 nM (S/N = 3). This good electroanalytical performance of AuPt/ZIF-8-rGO is owing to the ultrasmall size and high dispersion of the AuPtNPs, the strong metal-support interaction between the AuPtNPs and ZIF-8-rGO bisupport, and the sandwich-like structure comprising porous ZIF-8 and loosely packed rGO nanosheets. The AuPt/ZIF-8-rGO is employed for the practical detection of H2O2 in human serum samples with desirable properties. Therefore, the novel AuPt/ZIF-8-rGO is a promising nanozyme for various biotechnological and environmental applications.

14.
Anal Chem ; 91(18): 11938-11945, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31429273

RESUMO

Research about DNA composition has been concentrated on DNA damage in the past few decades. However, it still remains a great challenge to construct a rapid, facile, and accurate approach for simultaneously monitoring four DNA bases, guanine (G), adenine (A), thymine (T), and cytosine (C). Herein, a novel electrochemical sensor based on phenanthroimidazole derivative, 2-(4-bromophenyl)-1-phenyl-1H-phenanthro[9,10-d]-imidazole (PPI), is successfully fabricated by a simple electrochemical method. The bromophenyl group in PI could expand their aromatic plane, induce the π-conjugated extension, and enhance the charge transfer and π-π interaction. The phenyl group at N1 position could regulate the intermolecular interaction, which could promote the possibility of intermolecular connection. The PPI polymer (poly(PPI)) with π-electron enriched conjugation architecture has been applied in simultaneous determination of G, A, T, and C in neutral solution by square wave voltammetry (SWV) method with well-separated peak potentials at 0.714, 1.004, 1.177, and 1.353 V, respectively. The sensor functionalized with poly(PPI) exhibits wide linear response for G, A, T, and C in the concentration ranges of 3-300, 1-300, 30-800, and 20-750 µM, respectively. With favorable selectivity, stability, and reproducibility, the sensor is successfully utilized to monitor four DNA bases in real samples, displaying a promising prospect for electrochemical sensing devices.


Assuntos
Adenina/análise , Citosina/análise , Guanina/análise , Fenantrolinas/química , Timina/análise , Técnicas Biossensoriais , Catálise , Técnicas Eletroquímicas
15.
BMC Med Genet ; 20(1): 71, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053111

RESUMO

BACKGROUND: Nail-patella syndrome (NPS) is an autosomal dominant developmental disorder most commonly characterized by dyplasia of nail or patella, the radial head or the humeral head hypoplasia, and, frequently ocular abnormalities and renal disease. It is caused by heterozygous loss-of-function mutations in the LMX1B gene, which encodes LIM homeodomain transcription factor and is essential for regulating the dorsal limb fate. METHODS: A five generation pedigree was recruited. Genomic DNA was extracted from the peripheral blood samples. Mutation detection was performed by Sanger sequencing the LMX1B gene. In silico functional annotation of the variant was performed using the in silico predictors SIFT, PolyPhen-2 and Mutation Taster. RESULTS: A novel heterozygous small deletion within exon 4 of LMX1B, c.712_714delTTC, was identified in a rare five-generation NPS pedigree. The mutation resulted in a deletion of the conserved amino acid phenylalanine at codon 238 (p.Phe238del), which located in the homeodomain of LMX1B may abolish DNA binding with the molecule. Conformational prediction showed that the variation could transform the helical structure comprising p.Phe234, p.Lys235, p.Ala236, and p.Ser237. CONCLUSION: We identified a novel NPS-causing LMX1B mutation and expanded the spectrum of mutations in the LMX1B gene. The c.712_714delTTC mutation may affect the quaternary structure of LMX1B, which is essential for the specification of dorsal limb fate at both zeugopodal and autopodal levels, leading to typical NPS.


Assuntos
Deleção de Genes , Proteínas com Homeodomínio LIM/genética , Síndrome da Unha-Patela/genética , Fatores de Transcrição/genética , China , Códon , Éxons , Feminino , Heterozigoto , Humanos , Mutação com Perda de Função , Masculino , Linhagem
16.
Mikrochim Acta ; 186(4): 240, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30868250

RESUMO

An antifouling electrochemical aptasensor for ATP is described that has a zwitterionic self-assembled sensing interface on a glassy carbon electrode modified with a reduced graphene oxide carbon nanofiber (GO-CNF). The GO-CNF was first modified by self-polymerization of dopamine which provided a platform for simultaneously self-assembly of the ATP aptamer and cysteine. By using hexacyanoferrate as the electrochemical probe, in the presence of ATP, the aptamer strands fold around ATP molecules, thus leading to the variation of the electrochemical signal. The aptasensor has a linear response in the 0.1 pM to 5 nM ATP concentration range, and a 13 fM lower detection limit. The electrode is strongly resistant to nonspecific adsorption and biofouling. This enabled the detection of ATP even in spiked human plasma. Graphical abstract An antifouling electrochemical aptasensor employing reduced graphene oxide carbon nanofiber as conductive substrate and zwitterionic cysteine as antifouling material for adenosine triphosphate detection.


Assuntos
Trifosfato de Adenosina/sangue , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Grafite/química , Nanofibras/química , Cisteína/química , DNA/química , Espectroscopia Dielétrica/instrumentação , Espectroscopia Dielétrica/métodos , Eletrodos , Humanos , Limite de Detecção , Reprodutibilidade dos Testes
17.
J Immunol ; 197(9): 3490-3503, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27694491

RESUMO

Although chronic graft-versus-host disease (CGVHD) is the primary nonrelapse complication of allogeneic transplantation, understanding of its pathogenesis is limited. To identify the main operant pathways across the spectrum of CGVHD, we analyzed gene expression in circulating monocytes, chosen as in situ systemic reporter cells. Microarrays identified two interrelated pathways: 1) IFN-inducible genes, and 2) innate receptors for cellular damage. Corroborating these with multiplex RNA quantitation, we found that multiple IFN-inducible genes (affecting lymphocyte trafficking, differentiation, and Ag presentation) were concurrently upregulated in CGVHD monocytes compared with normal subjects and non-CGVHD control patients. IFN-inducible chemokines were elevated in both lichenoid and sclerotic CGHVD plasma and were linked to CXCR3+ lymphocyte trafficking. Furthermore, the levels of the IFN-inducible genes CXCL10 and TNFSF13B (BAFF) were correlated at both the gene and the plasma levels, implicating IFN induction as a factor in elevated BAFF levels in CGVHD. In the second pathway, damage-/pathogen-associated molecular pattern receptor genes capable of inducing type I IFN were upregulated. Type I IFN-inducible MxA was expressed in proportion to CGVHD activity in skin, mucosa, and glands, and expression of TLR7 and DDX58 receptor genes correlated with upregulation of type I IFN-inducible genes in monocytes. Finally, in serial analyses after transplant, IFN-inducible and damage-response genes were upregulated in monocytes at CGVHD onset and declined upon therapy and resolution in both lichenoid and sclerotic CGVHD patients. This interlocking analysis of IFN-inducible genes, plasma analytes, and tissue immunohistochemistry strongly supports a unifying hypothesis of induction of IFN by innate response to cellular damage as a mechanism for initiation and persistence of CGVHD.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Interferons/metabolismo , Monócitos/fisiologia , Adulto , Apresentação de Antígeno , Fator Ativador de Células B/metabolismo , Diferenciação Celular , Movimento Celular/genética , Quimiocina CXCL10/metabolismo , Doença Crônica , Proteína DEAD-box 58/metabolismo , Feminino , Humanos , Imunidade Inata , Masculino , Pessoa de Meia-Idade , Receptores CXCR3/metabolismo , Receptores Imunológicos , Receptores de Reconhecimento de Padrão/metabolismo , Transdução de Sinais , Receptor 7 Toll-Like/metabolismo , Transplante Homólogo , Adulto Jovem
19.
Clin Sci (Lond) ; 131(11): 1147-1159, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28381600

RESUMO

Airway remodelling is an important component of chronic obstructive pulmonary disease (COPD). Neutrophil gelatinase-associated lipocalin (NGAL) from neutrophils may drive COPD epithelial-mesenchymal transition (EMT). NGAL expression was quantified in the lungs of COPD patients and bronchoalveolar lavage fluid (BALF) of ozone-treated mice. Reticular basement membrane (RBM) thickness and E-cadherin and α-smooth muscle actin (α-SMA) expression were determined in mice airways. Effects of cigarette smoke extract (CSE) and inflammatory factors on NGAL expression in human neutrophils as well as the effects of NGAL on airway structural cells was assessed. NGAL was mainly distributed in neutrophils and enhanced in lung tissues of both COPD patients and BALF of ozone-treated mice. We showed decreased E-cadherin and increased α-SMA expression in bronchial epithelium and increased RBM thickness in ozone-treated animals. In vitro, CSE, IL-1ß and IL-17 enhanced NGAL mRNA expression in human neutrophils. NGAL, in turn, down-regulated the expression of E-cadherin and up-regulated α-SMA expression in 16HBE cells via the WNT/glycogensynthase kinase-3ß (GSK-3ß) pathway. Furthermore, NGAL promoted the proliferation and migration of human bronchial smooth muscle cells (HASMCs). The present study suggests that elevated NGAL promotes COPD airway remodelling possibly through altered EMT. NGAL may be a potential target for reversing airway obstruction and remodelling in COPD.


Assuntos
Remodelação das Vias Aéreas/fisiologia , Lipocalina-2/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Idoso , Animais , Membrana Basal/patologia , Brônquios/patologia , Líquido da Lavagem Broncoalveolar/citologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mediadores da Inflamação/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Lipocalina-2/genética , Lipocalina-2/metabolismo , Lipocalina-2/farmacologia , Pulmão/metabolismo , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Ozônio , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , RNA Mensageiro/genética , Fumar/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/fisiologia
20.
J Neurooncol ; 135(2): 343-351, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28756593

RESUMO

The immune system plays a significant role in cancer prevention and outcome. In high grade astrocytomas (HGA), severe lymphopenia is associated with shortened survival due to tumor progression. This study was performed to quantify serial changes in lymphocyte subsets in HGA following standard radiation (RT) and temozolomide (TMZ). Adults (KPS >60, HIV negative) with newly diagnosed HGA scheduled to receive concurrent RT and TMZ and adjuvant TMZ were eligible. Blood was collected before beginning concurrent RT/TMZ and at weeks 6, 10, 18, and 26, and 3 months after completing adjuvant TMZ. Lymphocyte subsets were analyzed by flow cytometry. Twenty patients (70% glioblastoma, median age 53, 50% male, 80% Caucasian) who enrolled from January 2014 to August 2014 were followed until April 2016. Baseline dexamethasone dose was 0.5 mg/day and 15% had absolute lymphocyte counts (ALC) <1000 cells/mm3 before starting RT/TMZ. However, 75% developed lymphopenia with ALC <1000 cells/mm3 after completion of RT/TMZ. NK cells, B cells and all T lymphocytes subsets dropped significantly after concurrent RT/TMZ and remained depressed for the 48 weeks of observation. The CD4+/CD8+ ratio was not affected significantly during follow-up. Severe lymphopenia involving all subsets occurred early in treatment and remained present for nearly 1 year. To our knowledge, this is the first report of serial trends in lymphocyte subsets following standard RT and TMZ for HGA.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Astrocitoma/terapia , Neoplasias do Sistema Nervoso Central/terapia , Quimiorradioterapia , Dacarbazina/análogos & derivados , Subpopulações de Linfócitos , Adulto , Idoso , Astrocitoma/sangue , Astrocitoma/imunologia , Astrocitoma/patologia , Neoplasias do Sistema Nervoso Central/sangue , Neoplasias do Sistema Nervoso Central/imunologia , Neoplasias do Sistema Nervoso Central/patologia , Dacarbazina/uso terapêutico , Feminino , Humanos , Estudos Longitudinais , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Prospectivos , Temozolomida , Resultado do Tratamento
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