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1.
Biosens Bioelectron ; 257: 116346, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38688230

RESUMO

The field of organic photoelectrochemical transistor (OPECT) is newly emerged, with increasing efforts attempting to utilize its properties in biological sensing. Advanced materials with new physicochemical properties have proven important to this end. Herein, we report a metal-organic polymers-gated OPECT biosensing exemplified by CuⅠ-arylacetylide polymers (CuAs)-modulated poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) channel. Both the photoelectrochemical properties and gating capability of CuAs are explored and optimized for high-efficacy photogating. Morever, based on its inherent structure, the specific reaction between CuAs and sulfur ions (S2-) is revealed and S2--mediated microRNA-21 detection is realized by linking with nucleic acid amplification and alkaline phosphatase catalytic chemistry. This work introduces metal-organic polymers as gating materials for OPECT biosensing.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , MicroRNAs , Polímeros , Poliestirenos , Transistores Eletrônicos , Técnicas Biossensoriais/instrumentação , Polímeros/química , Poliestirenos/química , MicroRNAs/análise , MicroRNAs/sangue , Cobre/química , Humanos , Fosfatase Alcalina/química , Limite de Detecção , Tiofenos
2.
World J Clin Cases ; 11(35): 8431-8433, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38130605

RESUMO

This article enthusiastically explores the study of highly aggressive variant prostate cancer (AVPC), acknowledging its relatively rare yet highly menacing presence within the realm of prostate cancer. The paper delves into the pathological characteristics of AVPC, diagnostic and therapeutic challenges, and the potential applications of precision medicine and molecular imaging in the future.

3.
Anal Chem ; 95(48): 17912-17919, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-37972240

RESUMO

The organic photoelectrochemical transistor (OPECT) has been proven to be a promising platform to study the rich light-matter-bio interplay toward advanced biomolecular detection, yet current OPECT is highly restrained to its intrinsic electronic amplification. Herein, this work first combines chemical amplification with electronic amplification in OPECT for dual-amplified bioanalytics with high current gain, which is exemplified by human immunoglobulin G (HIgG)-dependent sandwich immunorecognition and subsequent alkaline phosphatase (ALP)-mediated chemical redox cycling (CRC) on a metal-organic framework (MOF)-derived BiVO4/WO3 gate. The target-dependent redox cycling of ascorbic acid (AA) acting as an effective electron donor could lead to an amplified modulation against the polymer channel, as indicated by the channel current. The as-developed bioanalysis could achieve sensitive HIgG detection with a good analytical performance. This work features the dual chemical and electronic amplification for OPECT bioanalysis and is expected to stimulate further interest in the design of CRC-assisted OPECT bioassays.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Humanos , Técnicas Eletroquímicas , Oxirredução , Polímeros , Limite de Detecção
4.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(5): 857-864, 2023 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-37807740

RESUMO

OBJECTIVE: To explore the impacts of delayed ureteral stent removal on the quality of life (QoL) and mental health of urinary calculi postoperative patients due to the corona virus disease 2019(COVID-19) pandemic. METHODS: The demographic and clinical data of patients with ureteral stent placement after urinary endoscopic lithotripsy and returned to Peking University People's Hospital for stent removal from December 2019 to June 2020 were collected. Ureteral stent symptoms questionnaire (USSQ) score and the outcome 20-item self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were collected to estimate the QoL and mental status. The USSQ consisted of 44 questions in 6 domains (including urinary symptom, physical pain, general health, work performance, sexual function, and ureteral stent related infection). For most questions in each domain, its score was a five-point Likert-type scale from 1 to 5, and a small proportion of questions was quantified by 1 to 4 or 1 to 7 scale. SAS and SDS both contained 20 questions used to assess a patient's level of anxiety and depression. Its scoring for each item was on a four-point Likert-type scale from 1 to 4. A total score (ranging from 20 to 80) was the main statistical indicator. The level of clinical anxiety and depression was quantified by using standard scores (total score multiplied by 1.25 to produce integers). And the multi-group structural equation model was constructed by analysis of moment structure (AMOS) analysis. RESULTS: Overall, 71 patients were enrolled for analysis. It was found that the median duration of ureteral stent time differed significantly between the control and delayed groups for 32 (30, 33) d and 94.5 (88, 103) d, respectively. The delayed group resulted in higher scores in the USSQ multidimensional, which included urinary symptoms, general health, work performance and ureteral stent related infections. Anxiety and depression were also significantly serious in the delayed group than in the control group. A longer indwelling time of a ureteral stent could exacerbate the effects of urinary symptoms and physical pain on work performance (P=0.029 < 0.05). Among them, the patients with severe urinary symptoms leading to poor work performance were most significantly affected by prolonged ureteral stent duration time (CR=2.619>1.96). CONCLUSION: Patients with delayed ureteral stent removal due to the COVID-19 had resulted in worse QoL and mental status. Stents related symptoms are more severe in patients with higher anxiety and depression degree during COVID-19. To improve the QoL and mental health of patients after urinary calculi surgery during COVID-19, it is still not recommended to prolong the stent duration time or corresponding intervention measures should be taken.


Assuntos
COVID-19 , Ureter , Cálculos Ureterais , Doenças Ureterais , Cálculos Urinários , Humanos , Qualidade de Vida , Pandemias , COVID-19/epidemiologia , Ureter/cirurgia , Dor , Stents , Inquéritos e Questionários
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(5): 871-875, 2023 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-37807742

RESUMO

OBJECTIVE: To investigate the status quo of recognition and management of renal colic among urological surgeons in China. METHODS: From November 2021 to March 2022, 725 urological surgeons in China were surveyed in the form of a questionnaire, including their province, hospital grade, professional title, the number of patients with renal colic treated per week, the preferred drugs and the cognition of the disease. This study was approved by the Medical Ethics Committee of Peking University People's Hospital, and all respondents completed informed consent online. RESULTS: During November 2021 and March 2022, urological surgeons across China were surveyed in the form of a questionnaire, and the reliability and validity of the questionnaire were verified before the study was carried out. In the study, 720 valid questionnaires were collected (accounting for 99.31% of the total number), in which 42.4% of the doctors' preferred drugs were non-steroidal anti-inflammatory drugs (NSAIDs), and 40.0% of the doctors' preferred antispasmodic drugs. Opioids were the first choice of 11.0% of the physicians and other treatments were preferred by 6.6% of physicians. In addition, 61.1% of the doctors thought that the mechanism of renal colic was elevated prostaglandin, 32.2% thought it was ureteral spasm, 5.0% thought it was calculi irritation, and 1.7% thought the mechanism was unclear. The doctor of the cognition of the generation mechanism of renal colic pain had a significant influence on the preferred treatment option (χ2=54.399, P < 0.001) that the "elevated prostaglandins" doctor more often preferred NSAIDs than the doctor who thought cramps and ureter stones caused renal colic (51.6% vs. 28.0%, χ2=34.356, P < 0.001;51.6% vs. 19.4%, χ2=13.759, P < 0.001). In addition, hospital class, physician title, and the number of weekly consultations by physicians influenced the choice of medications for renal colic (P < 0.05), tertiary hospitals, middle and senior professional titles and weekly patients with renal colic > 8 cases generally preferred NSAIDs. CONCLUSION: There are deficiencies in the cognition and drug treatment of renal colic among urological surgeons in China. The choice of the preferred drug was related to the doctor's cognition of the disease, the grade of the hospital, the doctor's professional title and the weekly treatment volume.


Assuntos
Cólica Renal , Humanos , Cólica Renal/tratamento farmacológico , Urologistas , População do Leste Asiático , Reprodutibilidade dos Testes , Anti-Inflamatórios não Esteroides , Inquéritos e Questionários
6.
Environ Res ; 231(Pt 2): 116064, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37178750

RESUMO

Hypertensive disorders of pregnancy (HDP), including gestational hypertension (GH) and preeclampsia (PE), cause significant morbidity and mortality among pregnant women. Several environmental toxins, particularly those that affect the normal function of the placenta and the endothelium, are emerging as potential risk factors for HDP. Among them, per- and polyfluoroalkyl substances (PFAS), widely used in a variety of commercial products, have been related to a variety of adverse health effects including HDP. This study was conducted by searching three databases for observational studies reporting associations between PFAS and HDP, all of which were published before December 2022. We used random-effects meta-analysis to calculate pooled risk estimates, and assessing each combination of exposure and outcome for quality and level of evidence. In total, 15 studies were included in the systematic review and meta-analysis. The results from meta-analyses showed that risk of PE was increased with exposure to PFOA (perfluorooctanoic acid) (RR = 1.39, 95% CI = 1.05, 1.85; N = 6 studies; exposure = 1 ln-unit increment; low certainty), PFOS (perfluorooctane sulfonate) (RR = 1.51, 95% CI = 1.23, 1.86; N = 6 studies; exposure = 1 ln-unit increment; moderate certainty), and PFHxS (perfluorohexane sulfonate) (RR = 1.39, 95% CI = 1.10, 1.76; N = 6 studies; exposure = 1 ln-unit increment; low certainty). PFOS was also associated with an increased risk of HDP (RR = 1.39, 95% CI = 1.10, 1.76; exposure = 1 ln-unit increment; low certainty). Exposure to legacy PFAS (PFOA, PFOS, PFHxS) is associated with an increased risk of PE, and PFOS is further associated with HDP. In view of the limitations of meta-analysis and quality of evidence, these findings should be interpreted with caution. Further research is required that assesses exposure to multiple PFAS in diverse and well-powered cohorts.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Hipertensão Induzida pela Gravidez , Pré-Eclâmpsia , Humanos , Feminino , Gravidez , Hipertensão Induzida pela Gravidez/induzido quimicamente , Hipertensão Induzida pela Gravidez/epidemiologia , Poluentes Ambientais/toxicidade , Fluorocarbonos/toxicidade , Ácidos Alcanossulfônicos/toxicidade , Substâncias Perigosas , Estudos Observacionais como Assunto
7.
Sensors (Basel) ; 23(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36991919

RESUMO

Glucose sensors based blood glucose detection are of great significance for the diagnosis and treatment of diabetes because diabetes has aroused wide concern in the world. In this study, bovine serum albumin (BSA) was used to cross-link glucose oxidase (GOD) on a glassy carbon electrode (GCE) modified by a composite of hydroxy fullerene (HFs) and multi-walled carbon nanotubes (MWCNTs) and protected with a glutaraldehyde (GLA)/Nafion (NF) composite membrane to prepare a novel glucose biosensor. The modified materials were analyzed by UV-visible spectroscopy (UV-vis), transmission electron microscopy (TEM), and cyclic voltammetry (CV). The prepared MWCNTs-HFs composite has excellent conductivity, the addition of BSA regulates MWCNTs-HFs hydrophobicity and biocompatibility, and better immobilizes GOD on MWCNTs-HFs. MWCNTs-BSA-HFs plays a synergistic role in the electrochemical response to glucose. The biosensor shows high sensitivity (167 µA·mM-1·cm-2), wide calibration range (0.01-3.5 mM), and low detection limit (17 µM). The apparent Michaelis-Menten constant Kmapp is 119 µM. Additionally, the proposed biosensor has good selectivity and excellent storage stability (120 days). The practicability of the biosensor was evaluated in real plasma samples, and the recovery rate was satisfactory.


Assuntos
Técnicas Biossensoriais , Nanocompostos , Nanotubos de Carbono , Glucose/química , Nanotubos de Carbono/química , Glucose Oxidase/química , Soroalbumina Bovina/química , Técnicas Biossensoriais/métodos , Eletrodos , Nanocompostos/química , Enzimas Imobilizadas/química , Técnicas Eletroquímicas/métodos
8.
J Expo Sci Environ Epidemiol ; 33(1): 40-55, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35970987

RESUMO

BACKGROUND: Emerging evidence suggests that per- and polyfluoroalkyl substances (PFAS) are endocrine disruptors and may contribute to the etiology of diabetes. OBJECTIVES: This study aimed to systematically review the epidemiological evidence on the associations of PFAS with mortality and morbidity of diabetes and to quantitatively evaluate the summary effect estimates of the existing literature. METHODS: We searched three electronic databases for epidemiological studies concerning PFAS and diabetes published before April 1, 2022. Summary odds ratio (OR), hazard ratio (HR), or ß and their 95% confidence intervals (CIs) were respectively calculated to evaluate the association between PFAS and diabetes using random-effects model by the exposure type, and dose-response meta-analyses were also performed when possible. We also assessed the risk of bias of the studies included and the confidence in the body of evidence. RESULTS: An initial literature search identified 1969 studies, of which 22 studies were eventually included. The meta-analyses indicated that the observed statistically significant PFAS-T2DM associations were consistent in cohort studies, while the associations were almost non-significant in case-control and cross-sectional studies. Dose-response meta-analysis showed a "parabolic-shaped" association between perfluorooctanoate acid (PFOA) exposure and T2DM risk. Available evidence was rated with "low" risk of bias, and the level of evidence for PFAS and incident T2DM was considered "moderate". CONCLUSIONS: Our findings suggest that PFAS exposure may increase the risk of incident T2DM, and that PFOA may exert non-monotonic dose-response effect on T2DM risk. Considering the widespread exposure, persistence, and potential for adverse health effects of PFAS, further cohort studies with improvements in expanding the sample size, adjusting the covariates, and considering different types of PFAS exposure at various doses, are needed to elucidate the putative causal associations and potential mode of action of different PFAS on diabetes. IMPACT STATEMENT: A growing body of evidence suggests that per- and polyfluoroalkyl substances (PFAS) are endocrine disruptors and may contribute to the development of diabetes. However, epidemiological evidence on the associations of PFAS and diabetes is inconsistent. We performed this comprehensive systematic review and meta-analysis to quantitatively synthesize the evidence. The findings of this study suggest that exposure to PFAS may increase diabetes risk among the general population. Reduced exposure to these "forever and everywhere chemicals" may be an important preventative approach to reducing the risk of diabetes across the population.


Assuntos
Ácidos Alcanossulfônicos , Diabetes Mellitus Tipo 2 , Disruptores Endócrinos , Poluentes Ambientais , Fluorocarbonos , Humanos , Estudos Transversais , Disruptores Endócrinos/efeitos adversos , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/epidemiologia , Fluorocarbonos/efeitos adversos , Caprilatos/efeitos adversos
9.
Zool Res ; 43(5): 897-910, 2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36052554

RESUMO

Acute kidney injury (AKI) is a significant clinical complication with a substantial impact on morbidity and mortality, for which therapeutic options remain limited. The Hippo signaling pathway is an evolutionarily conserved pathway implicated in cell proliferation, dedifferentiation, and apoptosis via phosphorylation and inactivation of its downstream effectors Yes-associated protein (YAP)/transcriptional co-activator with PDZ-binding motif (TAZ). Recent studies have revealed that the Hippo pathway plays a pivotal role in the pathogenesis and repair of AKI. The Hippo pathway can mediate renal dysfunction through modulation of mitochondrial apoptosis under AKI conditions. Transient activation of YAP/TAZ in the acute phase of AKI may benefit renal recovery and regeneration, whereas persistent activation of YAP/TAZ in severe AKI may lead to maladaptive repair and transition to chronic kidney disease. This review aims to summarize recent findings on the associations between the Hippo pathway and AKI and to identify new therapeutic targets and strategies for AKI.


Assuntos
Injúria Renal Aguda , Proteínas Serina-Treonina Quinases , Injúria Renal Aguda/veterinária , Animais , Via de Sinalização Hippo , Transdução de Sinais/fisiologia , Fatores de Transcrição/metabolismo
10.
Biotechnol Bioeng ; 119(12): 3462-3473, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36131376

RESUMO

Phosphatases are a class of enzymes catalyzing the cleavage of monophosphate ester bonds from the phosphorylated substrates. They have important applications in construction of in vitro multi-enzymatic system for monosaccharides. However, the enzymes generally show substrate ambiguity, which has become a bottleneck for efficient biosynthesis of target products with high purity. In this study, semirational design was performed on phosphatase from Thermosipho atlanticus (Ta-PST). The hotspot amino acid residues forming a "cap domain" were identified and selected for saturation mutagenesis. The mutant F179T and F179M showed improved substrate preference toward fructose-6-phosphate and mannose-6-phosphate, respectively. Coupling with other enzymes involved in the multi-enzymatic system under optimized conditions, the application of F179T led to fructose yield of 80% from 10 g/L maltodextrin and the ratio between the target product and by-product glucose was increased from 2:1 to 19:1. On the other hand, the application of F179M led to mannose yield of 59% with ratio of mannose to the by-products glucose and fructose increased from 1:1:1 to 14:2:1. Moreover, the molecular understanding of the beneficial substitution was gained by structural analysis and molecular dynamic simulations, giving important guidance to regulate the enzyme's substrate preference.


Assuntos
Monossacarídeos , Monoéster Fosfórico Hidrolases , Especificidade por Substrato , Manose , Frutose , Glucose
11.
PeerJ ; 10: e13224, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547185

RESUMO

During a survey of culturable fungi in the coastal areas of China, three new species of Penicillium sect. Lanata-Divaricata were discovered and studied with a polyphasic taxonomic approach, and then named as P. donggangicum sp. nov. (ex-type AS3.15900T = LN5H1-4), P. hepuense sp. nov. (ex-type AS3.16039T = TT2-4X3, AS3.16040 = TT2-6X3) and P. jiaozhouwanicum sp. nov. (ex-type AS3.16038T = 0801H2-2, AS3.16207 = ZZ2-9-3). In morphology, P. donggangicum is unique in showing light yellow sclerotia and mycelium, sparse sporulation, restricted growth at 37 °C, irregular conidiophores, intercalary phialides and metulae, and pyriform to subspherical conidia. P. hepuense is distinguished by the fast growth on CYA and YES and slow growth on MEA at 25 °C, weak or absence of growth at 37 °C, biverticillate and monoverticillate penicilli, and ellipsoidal conidia. P. jiaozhouwanicum is characterized by abundant grayish-green conidia en masse and moderate growth at 37 °C, the appressed biverticillate penicilli and fusiform, smooth-walled conidia. These three novelties were further confirmed by the phylogenetic analyses based on either the combined BenA-CaM-Rpb2 or the individual BenA, CaM, Rpb2 and internal transcribed spacer (ITS) sequences.


Assuntos
Penicillium , Penicillium/genética , Filogenia , DNA Espaçador Ribossômico , DNA Fúngico/genética , China , Esporos Fúngicos
12.
Front Bioeng Biotechnol ; 10: 914280, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35615473

RESUMO

Arbutin is a hydroquinone glucoside and a natural product present in various plants. Arbutin potently inhibits melanin formation. This property has been exploited in whitening cosmetics and pharmaceuticals. Arbutin production relies mainly on chemical synthesis. The multi-step and complicated process can compromise product purity. With the increasing awareness of sustainable development, the current research direction prioritizes environment-friendly, biobased arbutin production. In this review, current strategies for arbutin production are critically reviewed, with a focus on plant extraction, chemical synthesis, biotransformation, and microbial fermentation. Furthermore, the bottlenecks and perspectives for future direction on arbutin biosynthesis are discussed.

13.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(2): 251-256, 2020 Apr 28.
Artigo em Chinês | MEDLINE | ID: mdl-32385034

RESUMO

Ubiquitin is a small molecule protein consisting of 76 amino acids,widely found in eukaryotic cells. The process by which ubiquitin binding to a specific protein is called ubiquitination. Deubiquitination is the reversed process of ubiquitination. Ubiquitination stimulates downstream signal,including complex assembly,protein conformation and activity changes,proteolysis,autophagy,guilt,chromatin remodeling,and DNA repair. More than 80% of eukaryotic protein degradation is mediated by the ubiquitination system,and ubiquitin-dependent proteolysis is an extremely complex process involving many biomolecular processes. By regulating protein homeostasis,ubiquitination can also regulate a variety of biological processes including cell cycle,cell proliferation,and apoptosis,which are closely related to tumorigenesis and progression. Many abnormalities of androgen receptor (AR) including AR gene amplification,mutation,shear mutation,and AR activity enhancement are closely related to prostate cancer progression. In particular,prostate cancer progression is regulated by the ubiquitination/deubiquitination processes. This article summarizes the recent research advances in the roles of ubiquitination/deubiquitination in AR abnormalities and prostate cancer.


Assuntos
Neoplasias da Próstata/patologia , Proteólise , Receptores Androgênicos/metabolismo , Ubiquitinação , Linhagem Celular Tumoral , Humanos , Masculino , Neoplasias da Próstata/metabolismo
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(3): 430-434, 2019 Jun 30.
Artigo em Chinês | MEDLINE | ID: mdl-31282342

RESUMO

Bladder cancer is a urological malignant tumor with high morbidity and mortality. Masses protruding into the bladder cavity is an important feature for clinical diagnosis of bladder cancer. However,patients with encrusted bladder cancer(EBC)do not present with masses protruding into the bladder cavity and thus this malignancy is often misdiagnosed. Four patients were admitted in Peking University People's Hospital from July 2015 to February 2017. All of them were males aged 40 to 77 years(mean:58 years). Patients were mainly manifested as frequent urination,urgency,nocturia,and decreased bladder capacity,with or without difficulty of voiding.Although the bladder walls were markedly thickened,there was no obvious mass on imaging scans. Three patients received urodynamic test,which showed the maximum capacity of the bladder was 41 to 128 ml(mean:91 ml). One patient presented with gross hematuria,two patients presented with microscopic hematuria,and the remaining one patient had no hematuria. No mass was observed by cystoscopy. All of the patients were diagnosed with bladder cancer by repeated biopsy or intraoperative frozen section analysis.


Assuntos
Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Adulto , Idoso , Biópsia , Cistoscopia , Hematúria , Humanos , Masculino , Pessoa de Meia-Idade
16.
Talanta ; 200: 494-502, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036214

RESUMO

An effective dithiourea-appended 1,8-naphthalimide fluorescent probe was designed and synthesized. This probe could recognize Hg2+ and Ag+ sensitively and selectively in neutral and alkaline conditions. Moreover, the probe detected Hg2+ alone at pH between 2 and 6. The sensing ability of the probe was explored by UV-vis, fluorescence, FTIR and 1H NMR spectroscopy. The probe was quenched by Hg2+ and Ag+ with 1:1 binding ratios in MeCN/H2O (4/1, v/v) mixed solution with binding constants of 3.76 × 104 L mol-1 and 2.47 × 104 L mol-1, respectively. The linear concentration ranges for Hg2+ and Ag+ were 0-17 µmol L-1 and 0-24 µmol L-1 with detection limits of 0.83 µmol L-1 and 1.20 µmol L-1, respectively, which allowed for the quantitative determination of Hg2+ and Ag+. The new probe, 3a, was successfully applied to the fluorescence imaging of Hg2+ and Ag+ in HepG2 cells, demonstrating its potential application in biological science. Moreover, 3a was used to measure Hg2+ and Ag+ in tap water, drinking water and ultrapure water samples. The recoveries of Hg2+ and Ag+ in water samples were 96-99% and 98-103%, respectively. Therefore, the proposed method showed promising perspectives for its application, aimed at detecting Hg2+ and Ag+ in fluorescence imaging and real water samples.


Assuntos
Corantes Fluorescentes/química , Mercúrio/análise , Naftalimidas/química , Imagem Óptica , Prata/análise , Tioureia/química , Corantes Fluorescentes/síntese química , Células Hep G2 , Humanos , Imagem Molecular , Estrutura Molecular , Células Tumorais Cultivadas
17.
J Agric Food Chem ; 65(30): 6274-6281, 2017 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-28691485

RESUMO

Better milk safety control can offer important means to promote public health. However, few technologies can detect different types of contaminants in milk simultaneously. In this regard, the present work proposes a single-drop Raman imaging (SDRI) strategy for semiquantitation of multiple hazardous factors in milk solutions. By developing SDRI strategy that incorporates the coffee-ring effect (a natural phenomenon often presents in a condensed circle pattern after a drop evaporated) for sample pretreatment and discrete wavelet transform for spectra processing, the method serves well to expose typical hazardous molecular species in milk products, such as melamine, sodium thiocyanate and lincomycin hydrochloride, with little sample preparation. The detection sensitivity for melamine, sodium thiocyanate, and lincomycin hydrochloride are 0.1 mg kg-1, 1 mg kg-1, and 0.1 mg kg-1, respectively. Theoretically, we establish that the SDRI represents a novel and environment-friendly method that screens the milk safety efficiently, which could be well extended to inspection of other food safety.


Assuntos
Contaminação de Alimentos/análise , Análise de Perigos e Pontos Críticos de Controle/métodos , Leite/química , Análise Espectral Raman/métodos , Animais , Tiocianatos/análise , Triazinas/análise
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 491-6, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30280541

RESUMO

In this paper, two-dimensional (2D) correlation spectroscopy analysis was applied to investigate the influence of the main component in blood and the systematic drift during the measurement on the specificity of glucose in the near-infrared (NIR) spectroscopy. First, the NIR transmittance of glucose aqueous solutions was measured and the 2D correlation NIR spectra were calculated under the perturbation of glucose concentration. Based on the comparative analysis for synchronous and asynchronous 2D correlation spectra, the characteristic absorption peaks of glucose in the combination band and the overtone band were determined. Then a small amount of albumin was added into glucose aqueous solutions, and the transmittance was recorded to perform 2D correlation spectroscopy analysis under the perturbation of glucose concentration. However, the absorption of glucose in the first overtone band (1590nm) and second overtone band (1195nm) was no longer homologous in the 2D correlation spectra, which means that the albumin may reduce the specificity of glucose. Further, the oral glucose tolerance test of healthy volunteer was conducted and the NIR diffuse reflectance of left palm was collected in vivo. The 2D correlation analysis results showed that, the homology of glucose in the diffuse reflectance was also destroyed. Moreover, as the spectral variation from the glucose concentration change is too low to be covered by that induced by systematic drift easily, some background correction methods were usually required. For the transmittance experiment of glucose aqueous solutions and the diffuse reflectance experiment of human body, the pure water sample and 5% diffuse reflectance standard were used as the reference, respectively. Then 2D correlation spectroscopy was developed under the perturbation of measurement time. Results showed that, smaller band shift was observed in the slice spectra of 2D correlation synchronous spectra after the corresponding background correction, and the specificity of glucose was improved both in the in vitro and in vivo experiments. So for the non-invasive glucose sensing by NIR spectroscopy, the wavelengths should be chosen carefully to avoid the absorption band of some interfering components which may destroy the homology of glucose and make spectral interpretation more complicated. And the selection of reference samples for relative measurement is also important to improve the specificity of glucose.


Assuntos
Glicemia/análise , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Água
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 561-6, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-27209769

RESUMO

The measurement of tissue optical parameters is the focusing research content of Biomedical Photonics. The optical properties of human tissue are closely related to the physiological and pathological state. In recent years, the tissue imaging diagnosis and non-invasive detection of componentsbecome the hot research topics, applying the tissue optical properties especially the absorption and scattering properties. These provide the basis for the study of optical imaging and the spectrum detection of body composition etc. The Double-Integrating-Spheres (DIS) method can measure the absorption coefficient, scattering coefficient and so on in vitro tissuesimultaneously. It has the advantages of accurate, rapid, large applicable scope. The method applya standard method for measuring the optical parameters. This paper build the wide spectrum measurement system of optical parameters based on DIS and super continuum lasers. Then we analyze the transfer function, error sources and the best measuring conditions of the system. Finally we establish the correction forward model based on BP-MCML and the inverse algorithm of the optical parameters based on L-M algorithm. The optical parameters of intralipid solution in the wavelength range of 1,100~1,400 nm are measured. The experiment results show that the improved inverse algorithm is accurate. The multiple measurements standard deviation is within 3%. Compared the results of scattering coefficient and absorption coefficient at different wavelengths to the results of other research groups, the deviation is less than 3.4%.


Assuntos
Composição Corporal , Análise Espectral , Algoritmos , Humanos , Modelos Teóricos
20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 38(6): 746-749, 2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-28065246

RESUMO

Chemokine-like factor super family member (CMTM) is a novel generic family firstly reported by Peking University Center for Human Disease Genomics. CMTM8 is one member of this family and has exhibited tumor-inhibiting activities. It can encode proteins approaching to the transmembrane 4 superfamily. CMTM8 is down-regulated in most carcinoma cell lines and tissues. Over-expression of CMTM8 may inhibit the proliferation,migration,and invasion of carcinoma cells. However,the exact mechanism of its anti-tumor activity remains unclear. CMTM8 may be involved in various signaling pathways governing the occurrence and development of tumors. CMTM8 may be a new target in the gene therapies for tumors,while further studies on CMTM8 and its anti-tumor mechanisms are warranted.


Assuntos
Quimiocinas/metabolismo , Proteínas com Domínio MARVEL/metabolismo , Neoplasias/metabolismo , Transdução de Sinais , Regulação para Baixo , Humanos
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