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1.
Anal Chem ; 96(32): 12991-12998, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39075986

RESUMO

With the increasing demand for trace sample analysis, injecting trace samples into liquid chromatography-mass spectrometry (LC-MS) systems with minimal loss has become a major challenge. Herein, we describe an in situ LC-MS analytical probe, the Falcon probe, which integrates multiple functions of high-pressure sample injection without sample loss, high-efficiency LC separation, and electrospray. The main body of the Falcon probe is made of stainless steel and fabricated by the computer numerical control (CNC) technique, which has ultrahigh mechanical strength. By coupling a nanoliter-scale droplet reactor made of polyether ether ketone (PEEK) material, the Falcon probe-based LC-MS system was capable of operating at mobile-phase pressures up to 800 bar, which is comparable to those of conventional ultraperformance liquid chromatography (UPLC) systems. Using the probe pressing microamount in situ (PPMI) injection approach, the Falcon probe-based LC-MS system showed high separation efficiency and good repeatability with relative standard deviations (RSDs) of retention time and peak area of 1.8% and 9.9%, respectively, in peptide mixture analysis (n = 6). We applied this system to the analysis of a trace amount of 200 pg of HeLa protein digest and successfully identified an average of 766 protein groups (n = 5). By combining in situ sample pretreatment at the nanoliter range, we further applied the present system in single-cell proteomic analysis, and 241 protein groups were identified in single 293 cells, which preliminarily demonstrated its potential in the analysis of trace amounts of samples with complex compositions.


Assuntos
Pressão , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Nanotecnologia , Polietilenoglicóis/química , Peptídeos/análise , Cromatografia Líquida de Alta Pressão , Células HeLa , Benzofenonas/análise , Benzofenonas/química , Polímeros/química , Cetonas/química , Cetonas/análise , Proteômica/métodos
2.
Anal Chem ; 96(14): 5499-5508, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38547315

RESUMO

Characterizing the profiles of proteome and metabolome at the single-cell level is of great significance in single-cell multiomic studies. Herein, we proposed a novel strategy called one-shot single-cell proteome and metabolome analysis (scPMA) to acquire the proteome and metabolome information in a single-cell individual in one injection of LC-MS/MS analysis. Based on the scPMA strategy, a total workflow was developed to achieve the single-cell capture, nanoliter-scale sample pretreatment, one-shot LC injection and separation of the enzyme-digested peptides and metabolites, and dual-zone MS/MS detection for proteome and metabolome profiling. Benefiting from the scPMA strategy, we realized dual-omic analysis of single tumor cells, including A549, HeLa, and HepG2 cells with 816, 578, and 293 protein groups and 72, 91, and 148 metabolites quantified on average. A single-cell perspective experiment for investigating the doxorubicin-induced antitumor effects in both the proteome and metabolome aspects was also performed.


Assuntos
Proteoma , Espectrometria de Massas em Tandem , Humanos , Proteoma/metabolismo , Cromatografia Líquida , Metaboloma , Células HeLa
3.
Chemphyschem ; 25(15): e202400330, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38676545

RESUMO

Copper is widely used in everyday life and industrial production because of its good electrical and thermal conductivity. To overcome copper oxidation and maintain its good physical properties, small organic molecules adsorbed on the surface of copper make a passivated layer to further avoid copper corrosion. In this work, we have investigated thioglycolic acid (TGA, another name is mercaptoacetic acid) adsorbed on copper surfaces by using density functional theory (DFT) calculations and a periodical slab model. We first get five stable adsorption structures, and the binding interaction between TGA and Cu(111) surfaces by using density of states (DOS), indicating that the most stable configuration adopts a triple-end binding model. Then, we analyze the vibrational Raman spectra of TGA adsorbed on the Cu(111) surface and make vibrational assignments according to the vibrational vectors. Finally, we explore the temperature effect of the thermodynamically Gibbs free energy of TGA on the Cu(111) surface and the antioxidant ability of the small organic molecular layer of copper oxidation on the copper surface. Our calculated results further provide evidences to interpret the stability of adsorption structures and antioxidant properties of copper.

4.
Langmuir ; 40(29): 14978-14989, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38946167

RESUMO

An atmospheric pressure plasma jet (APPJ) is used to process electrochemically deposited NiFe on carbon paper (NiFe/CP). The reactive oxygen and nitrogen species (RONs) of the APPJ modify the surface properties, chemical bonding types, and oxidation states of the material at the self-sustained temperature of the APPJ. The APPJ treatment further enhances the hydrophilicity and creates a higher disorder level in the carbon material. Moreover, the metal carbide bonds of NiFe/CP formed in the electrochemical deposition (ED) process are converted to metal oxide bonds after APPJ processing. The potential application of APPJ treatment on NiFe/CP in alkaline water electrolysis is demonstrated. With more oxygen-containing species and better hydrophilicity after APPJ treatment, APPJ-treated NiFe/CP is applied as the electrocatalyst for the oxygen evolution reaction (OER) in alkaline water electrolysis. APPJ-treated NiFe/CP is also used in a custom-made anion-exchange membrane water electrolyzer (AEMWE); this should contribute toward realizing the practical large-scale application of AEM for hydrogen production.

5.
Pharmacol Res ; 199: 107033, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38061593

RESUMO

Baicalin is a small molecule medication used to treat hepatitis. Our research group discovered that administering baicalin orally to mice following fecal microbiota transplantation from patients resistant to ICIs supported anti-PD-1 activity. However, the precise mechanisms behind this effect are presently unknown. In this present study, ATB-treated C57BL/6 J mice received FMT from patients with advanced NSCLC amenable to αPD-1. Additionally, subcutaneous LLC cells were injected into the mice. Baicalin oral gavage and αPD-1 injection were administered to the mice on days 3 and 9 after tumour inoculation. 16 S rRNA, metabolomics, and flow cytometry were utilized to clarify the mechanisms of baicalin's relief of immunosuppression. The results indicated that oral administration of baicalin enriched bacteria such as Akkermansia and Clostridia_UCG-014, resulted in an increase in SCFAs, which improved the ratio of PD-1+ (CD8+ T cell/Treg) and promoted the levels of IFN-γ+ CD8+ T cells and TNF-α+ CD8+ T cells within the tumour microenvironment. In conclusion, baicalin regulates the metabolites of the gut microbiota to improve the PD-1+ (CD8+ T cell/Treg) balance and circumvent anti-PD-1 resistance. This is achieved through the regulation of short-chain fatty acids.


Assuntos
Flavonoides , Microbioma Gastrointestinal , Humanos , Camundongos , Animais , Microbioma Gastrointestinal/fisiologia , Linfócitos T CD8-Positivos/metabolismo , Receptor de Morte Celular Programada 1 , Camundongos Endogâmicos C57BL , Ácidos Graxos Voláteis/metabolismo
6.
Anal Bioanal Chem ; 415(1): 17-25, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36334114

RESUMO

The continuing pursuit for a healthy life has led to the urgent need for on-site analysis. In response to the urgent needs of on-site analysis, we propose a novel concept, called lab at home (LAH), for building automated and integrated total analysis systems to perform chemical and biological testing at home. It represents an emerging research area with broad prospects that has not yet attracted sufficient attention. In this paper, we discuss the urgent need, challenges, and future prospects of this area, and the possible roadmap for achieving the goal of LAH has also been proposed.

7.
Gynecol Endocrinol ; 39(1): 2173948, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36750132

RESUMO

Objective: The aim of this study was to investigate the endometrial proteomic profiles of patients with polycystic ovary syndrome (PCOS) with and without insulin resistance (IR). Method of Study: We collected 40 endometrial samples, including PCOS-IR (n = 21), PCOS-non-IR (n = 12), and control (n = 7). Data-independent acquisition (DIA)-based proteomics method is used to identify the expressed proteins among the three groups. The correlation between pregnancy outcomes and identified proteins was analyzed by Lasso regression. Results: A total of 5331 proteins were identified, while 275 proteins were differentially expressed in the PCOS vs. control group and 215 proteins were differentially expressed in the PCOS-IR vs. PCOS-non-IR group. Platelet degranulation, neutrophil degranulation, and very long-chain fatty acid catabolic processes have been found to play important roles in the endometrium of patients with PCOS-IR. Lasso regression analysis found that ACTR1A, TSC22D2, CKB, ABRAXAS2, and TAGLN2 were associated with miscarriage in patients with PCOS. ACTR1A and CKB were higher in the PCOS-IR group and were positively correlated with HOMA-IR (p < .05). Conclusion: In this study, a panel of proteins was found to be differently expressed in the endometrium. ACTR1A and CKB may be considered as PCOS-IR candidate biomarkers.


Assuntos
Resistência à Insulina , Síndrome do Ovário Policístico , Feminino , Gravidez , Humanos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/metabolismo , Proteômica , Endométrio/metabolismo , Resultado da Gravidez , Insulina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo
8.
Int Wound J ; 20(10): 4244-4252, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37488713

RESUMO

Colorectal cancer is typically treated through surgery, and self-care skills play a crucial role in disease adaptation and quality of life improvement. Therefore, this study aimed to investigate the effectiveness of a multimedia patient education intervention on enhancing the self-care and quality of life among patients with a postoperative stoma as well as on establishing an easy-to-use ostomy self-care skills assessment. The sample comprised 108 patients with new ostomies who were randomly assigned to two groups. Data were collected from June 2018 to March 2019. The conventional education service program group received individual education in the hospital environment, consisting of four 3-h sessions delivered over 4 consecutive days. The multimedia group viewed a multimedia educational program using a laptop. Data were collected at baseline and 3 months after the intervention using a demographic questionnaire, an ostomy self-care ability scale and the Stoma Quality of Life Scale. Before the intervention, there were no significant differences in self-care ability and quality of life scores between the two groups (p = 0.764 and p = 0.466, respectively). However, 3 months after the intervention, the group that received the multimedia software intervention showed significantly higher self-care ability and quality of life scores compared to the group that received conventional education services (p < 0.001). When a set threshold is reached, self-care ability and a good quality of life can be met. The threshold value of the ostomy self-care skill scale was determined to be 20 points, resulting in a sensitivity of 77.8% and a specificity of 75.5%. The results indicate that the multimedia education program enhanced home self-care ability and quality of life among patients with enterostomy.


Assuntos
Enterostomia , Estomas Cirúrgicos , Humanos , Qualidade de Vida , Autocuidado/métodos , Multimídia
9.
J Am Chem Soc ; 144(9): 3821-3832, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35199991

RESUMO

Surface plasmon resonance (SPR) bridges photonics and photoelectrochemistry by providing an effective interaction between absorption and confinement of light to surface electrons of plasmonic metal nanostructures (PMNs). SPR enhances the Raman intensity enormously in surface-enhanced Raman spectroscopy (SERS) and leads to the plasmon-mediated chemical reaction on the surface of nanostructured metal electrodes. To observe variations in chemical reactivity and selectivity, we studied the SPR photoelectrochemical reactions of para-aminobenzoic acid (PABA) on nanostructured gold electrodes. The head-to-tail coupling product "4-[(4-imino-2,5-cyclohexadien-1-ylidene)amino]benzoic acid (ICBA)" and the head-to-head coupling product p,p'-azodibenzoate (ADBA) were obtained from PABA adsorbed on PMN-modified gold electrodes. In particular, under acidic and neutral conditions, ICBA was obtained as the main product, and ADBA was obtained as the minor product. At the same time, under basic conditions, ADBA was obtained as the major product, and ICBA was obtained as the minor product. We have also provided sufficient evidence for the oxidation of the tail-to-tail coupling reaction product that occurred in a nonaqueous medium rather than in an aqueous medium. The above finding was validated by the cyclic voltammetry, SERS, and theoretical calculation results of possible reaction intermediates, namely, 4-aminophenlylenediamine, 4-hydroxyphenlylenediamine, and benzidine. The theoretical adsorption model and experimental results indicated that PABA has been adsorbed as para-aminobenzoate on the gold cluster in a bidentate configuration. This work offers a new view toward the modulation of selective surface catalytic coupling reactions on PMN, which benefits the hot carrier transfer efficiency at photoelectrochemical interfaces.


Assuntos
Ouro , Nanoestruturas , Ácido 4-Aminobenzoico , Eletrodos , Ouro/química , Nanoestruturas/química , Ressonância de Plasmônio de Superfície/métodos
10.
Phys Chem Chem Phys ; 23(38): 22119-22132, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34580687

RESUMO

The investigation of the structural characteristics of chiral drugs in physiological environments is a challenging research topic, which may lead to a better understanding of how the drugs work. Raman optical activity (ROA) spectroscopy in combination with density functional theory (DFT) calculations was exploited to inspect the structural changes in penicillamine under different acid-base states in aqueous solutions. The B3LYP/aug-cc-PVDZ method was employed and the implicit solvation model density (SMD) was considered for describing the solvation effect in H2O. The conformations of penicillamine varied with pH, but penicillamine was liable to stabilize in the form of the PC conformation (the sulfur atom is in a trans orientation with respect to carboxylate) in most cases for both D- and L-isomers. The relationship between the conformations of penicillamine and the ROA peaks, as well as peak assignments, were comprehensively studied and elucidated. In the fingerprint region, two ROA couplets and one ROA triplet with different patterns were recognized. The intensity, sign and frequency of the corresponding peaks also changed with varying pH. Deuteration was carried out to identify the vibrational modes, and the ROA peaks of the deuterated amino group in particular are sensitive to change in the ambient environment. The results are expected not only to serve as a reference for the interpretation of the ROA spectra of penicillamine and other chiral drugs with analogous structures but also to evaluate the structural changes of chiral molecules in physiological environments, which will form the basis of further exploration of the effects of structural characteristics on the pharmacological and toxicological properties of chiral drugs.


Assuntos
Teoria da Densidade Funcional , Penicilamina/química , Concentração de Íons de Hidrogênio , Conformação Molecular , Análise Espectral Raman , Estereoisomerismo
11.
Pak J Pharm Sci ; 34(1): 35-39, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34248000

RESUMO

Multiple studies have discussed the associations between drugs affecting the renin-angiotensin-aldosterone system and the cancer risk, but their consequence s were conflicting. A meta-analysis of nested case-control studies published regarding this subject was conducted in our study, aims to estimate the association between ACEI/ARB and the cancer risk. Pubmed database was searched up to February, 1 2016 to identify eligible nested case-control studies, and we used Newcastle-Ottawa Scale (NOS) to assess quality of the studies. Pooled odds ratio (OR) and 95% confidence intervals (CIs) were calculated (with fixed effect model: Mantel-Haenszel). Publication bias and heterogeneity were evaluated before the calculation. Subgroup analysis and sensitivity analysis were also performed. Seven studies contributed to the analysis. Overall, ACEI/ARB use was not associated with the risk of cancer (OR=0.99, 95% CI 0.97-1.01), nor in long-term use patients (OR=0.97, 95% CI 0.92-1.01). ACEI may decrease cancer risk (OR=0.90, 95% CI 0.82-0.99). We observed no significant publication bias. In conclusion, ACEI/ARB use was not associated with cancer risk, nor in long-term use patients, but ACEI use may decrease cancer risk. More researches are needed to confirm these findings.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/metabolismo , Neoplasias/induzido quimicamente , Neoplasias/metabolismo , Sistema Renina-Angiotensina/efeitos dos fármacos , Antagonistas de Receptores de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Estudos de Casos e Controles , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Humanos , Neoplasias/epidemiologia , Preparações Farmacêuticas , Sistema Renina-Angiotensina/fisiologia , Fatores de Risco
12.
J Am Chem Soc ; 142(41): 17489-17498, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32941020

RESUMO

An attractive field of plasmon-mediated chemical reactions (PMCRs) is developing rapidly, but there is still incomplete understanding of how to control the kinetics of such a reaction related to hot carriers. Here, we chose 8-bromoadenine (8BrAd) as a probe molecule of hot electrons to investigate the influence of the electrode potential, laser wavelength, and power on the PMCR kinetics on silver nanoparticle-modified silver electrodes. Plasmonic hot electron-mediated cleavage of the C-Br bond in 8BrAd has been investigated by combining in situ electrochemical surface-enhanced Raman spectroscopy and density functional theory calculations. The experimental and theoretical results reveal that the energy position of plasmon relaxation-generated hot electrons can be modulated conveniently by applied potentials and laser light. This allows the proposal of a mechanism of modulating the matching energy of the hot electron of plasmon relaxation to promote the efficiency of PMCRs in electrochemical interfaces. Our work will be helpful to design surface plasmon resonance photoelectrochemical reactions on metal electrode surfaces of nanostructures with higher efficiency.

13.
Cell Commun Signal ; 18(1): 128, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807176

RESUMO

BACKGROUND: The activation of the NF-κB pathway plays a crucial role in the progression of breast cancer (BCa) and also involved in endocrine therapy resistance. On the contrary to the canonical NF-κB pathway, the effect of the noncanonical NF-κB pathway in BCa progression remains elusive. METHODS: BCa tumor tissues and the corresponding cell lines were examined to determine the correlation between RelB and the aggressiveness of BCa. RelB was manipulated in BCa cells to examine whether RelB promotes cell proliferation and motility by quantitation of apoptosis, cell cycle, migration, and invasion. RNA-Seq was performed to identify the critical RelB-regulated genes involved in BCa metastasis. Particularly, RelB-regulated MMP1 transcription was verified using luciferase reporter and ChIP assay. Subsequently, the effect of RelB on BCa progression was further validated using BCa mice xenograft models. RESULTS: RelB uniquely expresses at a high level in aggressive BCa tissues, particularly in triple-negative breast cancer (TNBC). RelB promotes BCa cell proliferation through increasing G1/S transition and/or decreasing apoptosis by upregulation of Cyclin D1 and Bcl-2. Additionally, RelB enhances cell mobility by activating EMT. Importantly, RelB upregulates bone metastatic protein MMP1 expression through binding to an NF-κB enhancer element located at the 5'-flanking region. Accordingly, in vivo functional validation confirmed that RelB deficiency impairs tumor growth in nude mice and inhibits lung metastasis in SCID mice. Video abstract.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Hormônios/farmacologia , NF-kappa B/metabolismo , Transdução de Sinais , Fator de Transcrição RelB/metabolismo , Animais , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/secundário , Neoplasias da Mama/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Metaloproteinase 1 da Matriz/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Biológicos , Invasividade Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Fator de Transcrição RelB/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
14.
Nutr Cancer ; 72(3): 513-521, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31274008

RESUMO

Background: The protective role of green tea against cancer is still unknown.Objectives: To investigate the association between green tea consumption and esophageal cancer risk through meta-analysis.Methods: We searched MEDLINE, EMBASE, Web of Science and Cochrane Library for studies on the relationship between green tea and esophageal cancer risk. We assessed heterogeneity (I2) and publication bias (Begg's and Egger's tests). Pooled relative risks (RRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random effects models.Results: A total of 20 studies were included. The RRs for all studies was 0.65 (95% CI: 0.57-0.73), with I2 = 75.3% and P = 0. In the subgroup analysis, the following variables showed marked heterogeneity: Asian (RR: 0.64; 95% CI: 0.56-0.73) and non-Asian countries (RR: 0.74; 95% CI: 0.45-1.03), female (RR: 0.55; 95% CI: 0.39-0.71) and male + female (RR: 0.64; 95% CI: 0.54-0.75), case-control study (RR: 0.62; 95% CI: 0.52-0.71), impact factor >3 (RR: 0.65; 95% CI: 0.56-0.75), impact factor <3 (RR: 0.64; 95% CI: 0.48-0.80), Newcastle-Ottawa Scale >7 (RR: 0.82; 95% CI: 0.66-0.97) and Newcastle-Ottawa Scale ≤7 (RR: 0.59; 95% CI: 0.49-0.68).Conclusion: Green tea consumption could be a protective factor for esophageal cancer.


Assuntos
Neoplasias Esofágicas/epidemiologia , Chá , Ásia/epidemiologia , Povo Asiático/estatística & dados numéricos , Estudos de Casos e Controles , Estudos de Coortes , Intervalos de Confiança , Neoplasias Esofágicas/prevenção & controle , Feminino , Humanos , Masculino , Razão de Chances , Fatores de Risco , Fatores Sexuais
15.
J Am Chem Soc ; 141(4): 1665-1671, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30608680

RESUMO

Perovskite solar cells are strong competitors for silicon-based ones, but suffer from poor long-term stability, for which the intrinsic stability of perovskite materials is of primary concern. Herein, we prepared a series of well-defined cesium-containing mixed cation and mixed halide perovskite single-crystal alloys, which enabled systematic investigations on their structural stabilities against light, heat, water, and oxygen. Two potential phase separation processes are evidenced for the alloys as the cesium content increases to 10% and/or bromide to 15%. Eventually, a highly stable new composition, (FAPbI3)0.9(MAPbBr3)0.05(CsPbBr3)0.05, emerges with a carrier lifetime of 16 µs. It remains stable during at least 10 000 h water-oxygen and 1000 h light stability tests, which is very promising for long-term stable devices with high efficiency. The mechanism for the enhanced stability is elucidated through detailed single-crystal structure analysis. Our work provides a single-crystal-based paradigm for stability investigation, leading to the discovery of stable new perovskite materials.

16.
Anal Chem ; 91(3): 1779-1784, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30608139

RESUMO

Digital PCR is a powerful method for absolute nucleic acid quantification with unprecedented accuracy and precision. To promote the wider use and application of digital PCR, several major challenges still exist, including reduction of cost, integration of the instrumental platform, and simplification of operations. This paper describes a reusable microfluidic device that generates nanoliter droplet arrays based on step emulsification for the on-chip multiplex digital PCR of eight samples simultaneously. The device contains two glass plates that can be quickly assembled with prefilled mineral oil. Droplets are simply generated through the arrays of step emulsification nozzles driven by a single pressure controller and are self-assembled into monolayer droplet arrays in U-shaped chambers. The use of mineral oil eliminates bubble generation; thus, no overpressure is required during thermocycling. Moreover, the device can be reused many times after disassembly and a brief cleaning procedure, which significantly reduces the cost of the device per dPCR assays. The device was able to detect template DNA at concentrations as low as 10 copies/µL with a dynamic range of approximately 4 logs. We applied this device in the quantitative assessment of HER2 copy number variation, which is important for targeted therapy and prognosis of breast cancer. The performance was validated by 16 clinical samples, obtaining similar results to commercial digital PCR. We envision that this low-cost, reusable, and user-friendly device can be broadly used in various applications.


Assuntos
DNA de Neoplasias/análise , Dispositivos Lab-On-A-Chip , Reação em Cadeia da Polimerase Multiplex/métodos , Neoplasias da Mama/genética , Variações do Número de Cópias de DNA , DNA de Neoplasias/genética , Emulsões/química , Vidro/química , Humanos , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Óleo Mineral/química , Reação em Cadeia da Polimerase Multiplex/instrumentação , Receptor ErbB-2/genética
17.
Arch Gynecol Obstet ; 297(3): 731-740, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29327157

RESUMO

OBJECTIVE: The study aimed to systematically review the association between angiogenesis and clinicopathological characteristics and its prognostic value in patients with endometrial cancer. METHODS: Eligible studies were searched in PubMed, Embase, China National Knowledge Infrastructure, and Wanfang database. Studies that assessed blood microvessel density (BMVD) and correlated with clinicopathological features and/or overall survival (OS) were included. Geometric mean values and hazard ratio with 95% confidence interval were pooled to examine the risk or hazard association. Subgroup analyses were conducted based on populations, BMVD criteria, BMVD markers, and type of survival analysis. RESULTS: A total of 29 studies of 2517 patients were included. BMVD was associated with depth of myometrial invasion (MI) [standard mean difference (SMD) 1.24; 95% CI 0.53-1.95; P = 0.0006], lymphovascular space invasion (LVSI) (SMD 0.75; 95% CI 0.3-1.21; P = 0.001), and lymph node metastasis (LNM) (SMD 0.99; 95% CI 0.46-1.52; P = 0.0003). BMVD was also significantly associated with poor OS (HR 2.65; 95% CI 1.86-3.77; P < 0.00001). The association remained significant in the subgroups Asian population, BMVD criteria using Weidner method, BMVD marker CD34 for MI, LVSI, and LNM, CD105 for MI, and factor VIII for MI and LNM, respectively. For OS, either Asian or non-Asian population, BMVD criteria using Weidner or non-Weidner method, BMVD marker CD31, or factor VIII antibody and analysis using univariate or multivariate were all significantly associated. CONCLUSIONS: BMVD was associated with deeper MI, positive LVSI, positive LNM, and poor OS in patients with endometrial cancer. Therefore, angiogenesis is a useful measure for poor clinicopathological outcomes and prognosis in patients with endometrial cancer.


Assuntos
Neoplasias do Endométrio/patologia , Metástase Linfática/patologia , Vasos Linfáticos/patologia , Microvasos/patologia , Miométrio/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
18.
Sensors (Basel) ; 18(2)2018 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-29419745

RESUMO

A review for optical fiber sensors based on fiber ring laser (FRL) demodulation technology is presented. The review focuses on the principles, main structures, and the sensing performances of different kinds of optical fiber sensors based on FRLs. First of all, the theory background of the sensors has been discussed. Secondly, four different types of sensors are described and compared, which includes Mach-Zehnder interferometer (MZI) typed sensors, Fabry-Perot interferometer (FPI) typed sensors, Sagnac typed sensors, and fiber Bragg grating (FBG) typed sensors. Typical studies and main properties of each type of sensors are presented. Thirdly, a comparison of different types of sensors are made. Finally, the existing problems and future research directions are pointed out and analyzed.

19.
Acc Chem Res ; 49(11): 2596-2604, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27668827

RESUMO

In the past several decades, electrochemical machining (ECM) has enjoyed the reputation of a powerful technique in the manufacturing industry. Conventional ECM methods can be classified as electrolytic machining and electroforming: the former is based on anodic dissolution and the latter is based on cathodic deposition of metallic materials. Strikingly, ECM possesses several advantages over mechanical machining, such as high removal rate, the capability of making complex three-dimensional structures, and the practicability for difficult-to-cut materials. Additionally, ECM avoids tool wear and thermal or mechanical stress on machining surfaces. Thus, ECM is widely used for various industrial applications in the fields of aerospace, automobiles, electronics, etc. Nowadays, miniaturization and integration of functional components are becoming significant in ultralarge scale integration (ULSI) circuits, microelectromechanical systems (MEMS), and miniaturized total analysis systems (µ-TAS). As predicted by Moore's law, the feature size of interconnectors in ULSI circuits are down to several nanometers. In this Account, we present our perseverant research in the last two decades on how to "confine" the ECM processes to occur at micrometer or even nanometer scale, that is, to ensure ECM with nanoscale accuracy. We have been developing the confined etchant layer technique (CELT) to fabricate three-dimensional micro- and nanostructures (3D-MNS) on different metals and semiconductor materials since 1992. In general, there are three procedures in CELT: (1) generating the etchant on the surface of the tool electrode by electrochemical or photoelectrochemical reactions; (2) confining the etchant in a depleted layer with a thickness of micro- or nanometer scale; (3) feeding the tool electrode to etch the workpiece. Scavengers, which can react with the etchant, are usually adopted to form a confined etchant layer. Through the subsequent homogeneous reaction between the scavenger and the photo- or electrogenerated etchant in the electrolyte solution, the diffusion distance of the etchant is confined to micro- or nanometer scale, which ensures the nanoscale accuracy of electrochemical machining. To focus on the "confinement" of chemical etching reactions, external physical-field modulations have recently been introduced into CELT by introducing various factors such as light field, force field, hydrodynamics, and so on. Meanwhile, kinetic investigations of the confined chemical etching (CCE) systems are established based on the finite element analysis and simulations. Based on the obtained kinetic parameters, the machining accuracy is tunable and well controlled. CELT is now applicable for 1D milling, 2D polishing, and 3D microfabrication with an accuracy at nanometer scale. CELT not only inherits all the advantages of electrochemical machining but also provides advantages over photolithography and nanoimprint for its applicability to different functional materials without involving any photocuring and thermoplastic resists. Although there are some technical problems, for example, mass transfer and balance, which need to be solved, CELT has shown its prospective competitiveness in electrochemical micromachining, especially in the semiconductor industry.

20.
Cell Mol Neurobiol ; 37(6): 1043-1054, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27807758

RESUMO

Olfactory ensheathing cells (OECs) are a type of glia from the mammalian olfactory system, with neuroprotective and regenerative properties. ß-Amyloid peptides are a major component of the senile plaques characteristic of the Alzheimer brain. The amyloid beta (Aß) precursor protein is cleaved to amyloid peptides, and Aß25-35 is regarded to be the functional domain of Aß, responsible for its neurotoxic properties. It has been reported that Aß25-35 triggers reactive oxygen species (ROS)-mediated oxidative damage, altering the structure and function of mitochondria, leading to the activation of the mitochondrial intrinsic apoptotic pathway. Our goal is to investigate the effects of OECs on the toxicity of aggregated Aß25-35, in human neuroblastoma SH-SY5Y cells. For such purpose, SH-SY5Y cells were incubated with Aß25-35 and OEC-conditioned medium (OECCM). OECCM promoted the cell viability and reduced the apoptosis, and decreased the intracellular ROS and the lipid peroxidation. In the presence of OECCM, mRNA and protein levels of antioxidant enzymes (SOD1 and SOD2) were upregulated. Concomitantly, OECCM decreased mRNA and the protein expression levels of cytochrome c, caspase-9, caspase-3, and Bax in SH-SY5Y cells, and increased mRNA and the protein expression level of Bcl-2. However, OECCM did not alter intracellular Ca2+ concentration in SH-SY5Y cells. Taken together, our data suggest that OECCM ameliorates Aß25-35-induced oxidative damage in neuroblastoma SH-SY5Y cells by inhibiting the mitochondrial intrinsic pathway. These data provide new insights into the functional actions of OECCM on oxidative stress-induced cell damage.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Apoptose/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Mitocôndrias/metabolismo , Bulbo Olfatório/citologia , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/toxicidade , Transdução de Sinais/efeitos dos fármacos , Animais , Cálcio/metabolismo , Linhagem Celular Tumoral , Humanos , Mitocôndrias/efeitos dos fármacos , Oxirredução , Ratos , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/metabolismo
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