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1.
Adv Healthc Mater ; : e2401097, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38800937

ABSTRACT

The utilization of surface plasmon resonance (SPR) sensors for real-time label-free molecular interaction analysis is already being employed in the fields of in vitro diagnostics and biomedicine. However, the widespread application of SPR technology is hindered by its limited detection throughput and high cost. To address this issue, this study introduces a novel multifunctional MetaSPR high-throughput microplate biosensor featuring 3D nanocups array structure, aiming to achieve high-throughput screening with a reduced cost and enhanced speed. Different types of MetaSPR sensors and analytical detection methods have been developed for accurate antibody subtype identification, epitope binding, affinity determination, antibody collocation, and quantitative detection, greatly promoting the screening and analysis of early-stage antibody drugs. The MetaSPR platform combined with nano-enhanced particles amplifies the detection signal and improves the detection sensitivity, making it more convenient, sensitive, and efficient than traditional ELISA. The findings demonstrate that the MetaSPR biosensor is a new practical technology detection platform that can improve the efficiency of biomolecular interaction studies with unlimited potential for new drug development.

2.
Biosens Bioelectron ; 248: 115974, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38171221

ABSTRACT

The accumulation of trace amounts of certain small molecules in food poses considerable human health challenges, including the potential for carcinogenesis and mutagenesis. Here, an ultrasensitive gold-platinum nanoflower-coupled metasurface plasmon resonance (MetaSPR) (APNMSPR) biosensor, based on a competitive immunoassay, was developed for the multiplexed and rapid quantitative analysis of trace small molecules in eggs, offering timely monitoring of food safety. This one-step biosensor can be integrated into either a newly designed detachable high-throughput MetaSPR chip-strip plate device or a standard 96-well plate for multiplexed small-molecule detection within a single egg. The limits of detection were 0.81, 1.12, and 1.74 ppt for florfenicol, fipronil, and enrofloxacin, respectively, demonstrating up to 1000-fold increased sensitivity and a 15-fold reduction in analysis time compared with those of traditional methods. The results obtained using the APNMSPR biosensor showed a strong correlation with those obtained using liquid chromatography-tandem mass spectrometry. The APNMSPR biosensor holds immense promise for the multiplexed, highly sensitive, and rapid quantitative analysis of small molecules for applications in food safety control, early diagnosis, and environmental monitoring.


Subject(s)
Biosensing Techniques , Humans , Biosensing Techniques/methods , Surface Plasmon Resonance/methods , Hazard Analysis and Critical Control Points , Gold/chemistry , Eggs , Immunoassay/methods
3.
J Eur Acad Dermatol Venereol ; 38(3): 530-542, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38031478

ABSTRACT

BACKGROUND: Evidence on the (long-term) safety of systemic immunomodulating therapies in atopic dermatitis (AD) generated by real-world data is sparse. OBJECTIVES: To describe real-world reported adverse drug reactions (AEs) related to systemic immunomodulating therapy in patients with AD and to compare the incidence rates of AEs with the Summaries of Product Characteristics (SmPCs). METHODS: We conducted an observational prospective multi-centre cohort study, using the TREAT NL registry. All severe AEs, AEs of special interest and serious AEs in adult and paediatric patients on systemic immunomodulating treatment (ciclosporin, methotrexate, azathioprine, mycophenolic acid, dupilumab, tralokinumab, baricitinib and upadacitinib) were assessed. Incidences rates of all (potentially) drug-related AEs were standardized in patient years and compared to the cumulative incidences in the associated SmPCs. RESULTS: We collected 422 patient years of safety data from 266 patients, of whom 129 (48.5%) reported a total of 224 (potentially) drug-related AEs. Compared to dupilumab's SmPC, higher incidence rates were found for four AEs (reported ≥5 times): eosinophilia, blepharitis, dry eyes and head and neck erythema (i.e. dupilumab facial redness). A higher incidence rate of fatigue was found in patients on oral methotrexate in our cohort compared to the SmPC. Two new drug-related AEs (reported ≥5 times) were found in patients on dupilumab, including non-infectious conjunctivitis and meibomian gland dysfunction. CONCLUSIONS: Real-world reported AEs captured in AD patient registries can add information on the estimated incidence of AEs and benefit clinical decision aids. Future studies using data derived from the TREAT NL registry combined with data from other registries within the TREAT Registry Taskforce will provide more information on (rare) AEs associated with immunomodulating therapy in AD patients.


Subject(s)
Dermatitis, Atopic , Adult , Humans , Child , Netherlands/epidemiology , Cohort Studies , Dermatitis, Atopic/drug therapy , Methotrexate/adverse effects , Prospective Studies
4.
Opt Express ; 31(13): 21586-21613, 2023 Jun 19.
Article in English | MEDLINE | ID: mdl-37381254

ABSTRACT

Technological innovation, cost effectiveness, and miniaturization are key factors that determine the commercial adaptability and sustainability of sensing platforms. Nanoplasmonic biosensors based on nanocup or nanohole arrays are attractive for the development of various miniaturized devices for clinical diagnostics, health management, and environmental monitoring. In this review, we discuss the latest trends in the engineering and development of nanoplasmonic sensors as biodiagnostic tools for the highly sensitive detection of chemical and biological analytes. We focused on studies that have explored flexible nanosurface plasmon resonance systems using a sample and scalable detection approach in an effort to highlight multiplexed measurements and portable point-of-care applications.


Subject(s)
Environmental Monitoring , Vibration
5.
Adv Sci (Weinh) ; 10(24): e2301658, 2023 08.
Article in English | MEDLINE | ID: mdl-37358326

ABSTRACT

Developing plasmonic biosensors that are low-cost, portable, and relatively simple to operate remains challenging. Herein, a novel metasurface plasmon-etch immunosensor is described, namely a nanozyme-linked immunosorbent surface plasmon resonance biosensor, for the ultrasensitive and specific detection of cancer biomarkers. Gold-silver composite nano cup array metasurface plasmon resonance chip and artificial nanozyme-labeled antibody are used in two-way sandwich analyte detection. Changes in the biosensor's absorption spectrum are measured before and after chip surface etching, which can be applied to immunoassays without requiring separation or amplification. The device achieved a limit of alpha-fetoprotein (AFP) detection < 21.74 fM, three orders of magnitude lower than that of commercial enzyme-linked immunosorbent assay kits. Additionally, carcinoembryonic antigen (CEA) and carbohydrate antigen 125 (CA125) are used for quantitative detection to verify the universality of the platform. More importantly, the accuracy of the platform is verified using 60 clinical samples; compared with the hospital results, the three biomarkers achieve high sensitivity (CEA: 95.7%; CA125: 90.9%; AFP: 86.7%) and specificity (CEA: 97.3%; CA125: 93.9%; AFP: 97.8%). Due to its rapidity, ease of use, and high throughput, the platform has the potential for high-throughput rapid detection to facilitate cancer screening or early diagnostic testing in biosensing.


Subject(s)
Biosensing Techniques , Neoplasms , Biomarkers, Tumor , Carcinoembryonic Antigen , Biosensing Techniques/methods , alpha-Fetoproteins , Early Detection of Cancer , Immunoassay/methods , Catalysis , Neoplasms/diagnosis
6.
Biosens Bioelectron ; 225: 115084, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-36693286

ABSTRACT

The microRNA21 (miR-21), a specific tumor biomarker, is crucial for the diagnosis of several cancer types, and investigation of its overexpression pattern is important for cancer diagnosis. Herein, we report a low-cost, rapid, ultrasensitive, and convenient biosensing strategy for the detection of miR-21 using a nanoplasmonic array chip coupled with gold nanoparticles (AuNPs). This sensing platform combines the surface plasmon resonance effect of nanoplasmonics (NanoSPR) and the localized surface plasmon resonance (LSPR) effect, which allows the real-time monitoring of the subtle optical density (OD) changes caused by the variations in the dielectric constant in the process of the hybridization of the target miRNA. Using this method, the miRNA achieves a broad detection range from 100 aM to 1 µM, and with a limit of detection (LoD) of 1.85 aM. Furthermore, this assay also has a single-base resolution to discriminate the highly homologous miRNAs. More importantly, this platform has high throughput characteristics (96 samples can be detected simultaneously). This strategy exhibits more than 86.5 times enhancement in terms of sensitivity compared to that of traditional biosensors.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , MicroRNAs , Neoplasms , Humans , Biosensing Techniques/methods , Gold , Biomarkers, Tumor/genetics , Surface Plasmon Resonance/methods , MicroRNAs/genetics , Neoplasms/diagnosis , Neoplasms/genetics , Limit of Detection
7.
Chem Eng J ; 451: 138822, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36060034

ABSTRACT

The novel mutations attributed by the high mutagenicity of the SARS-CoV-2 makes its prevention and treatment challenging. Developing an ultra-fast, point-of-care-test (POCT) protocol is critical for responding to large-scale spread of SARS-CoV-2 in public places and in resource-poor remote areas. Here, we developed a nanoplasmonic enhanced isothermal amplification (NanoPEIA) strategy that combines a nanoplasmonic sensor with isothermal amplification. The novel strategy provides an ideal easy-to operate detection platform for obtaining accurate, ultra-fast and high-throughput (96 samples can be tested together) data. For clinical samples with viral detection at Ct value <25, the entire process (including sample preparation, virus lysis, detection, and data analysis) can be completed within six minutes. The method is also appropriate for detection of SARS-CoV-2 γ-coronavirus mutants. The NanoPEIA method was validated using clinical samples from 21 patients with SARS-CoV-2 infection and 31 healthy individuals. The detection result on the 52 clinical samples for SARS-CoV-2 showed that the NanoPEIA platform had a 100% sensitivity for N and orf1ab genes, which was higher than those obtained using RT-qPCR (88.9% and 90.0%, respectively). The specificities of 31 clinical negative samples were 92.3% and 91.7% for the N gene and the orf1ab gene, respectively. The limits of detection (LoD) of the clinical samples were 28.3 copies/mL and 23.3 copies/mL for the N gene and the orf1ab gene, respectively. The efficient NanoPEIA detection strategy facilitates real-time detection and visualization within ultrashort durations and can be applied for POCT diagnosis in resource-poor and highly populated areas.

8.
Mater Today Bio ; 16: 100444, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36204214

ABSTRACT

Accurate determination of the concentration and viability of the viral vaccine vectors is urgently needed for preventing the spread of the viral infections, but also supporting the development and assessment of recombinant virus-vectored vaccines. Herein, we describe a nanoplasmonic biosensor with nanoscale robot hand structure (Nano RHB) for the rapid, direct, and specific capture and quantification of adenovirus particles. The nanorobot allows simple operation in practical applications, such as real-time monitoring of vaccine quantity and quality, and evaluation of vaccine viability. Modification of the Nano RHB with branched gold nanostructures allow rapid and efficient assessment of human adenovirus viability, with ultrahigh detection sensitivity of only 100 copies/mL through one-step sandwich method. Nano RHB detection results were consistent with those from the gold standard median tissue culture infectious dose and real-time polymerase chain reaction assays. Additionally, the Nano RHB platform showed high detection specificity for different types of viral vectors and pseudoviruses. Altogether, these results demonstrate that the Nano RHB platform is a promising tool for efficient and ultrasensitive assessment of vaccines and gene delivery vectors.

9.
Microbiol Spectr ; 10(6): e0234322, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36314937

ABSTRACT

African swine fever (ASF) is one of the most serious transnational swine diseases in the world. The case fatality rate of susceptible pigs is up to 100%. Currently, no commercial vaccine is available, so the prevention and control of ASF mainly relies on early diagnosis and culling of infected pigs. As the ASF virus continues to evolve, develop, and diversify, nucleic acid testing becomes less efficient. Here, we developed a method for the rapid and direct optical measurement of African swine fever virus (ASFV) antibody in vitro. This one-step procedure requires nearly no sample preparation and involves p30 protein-specific label-free integration into standard 96-well plates. Using a nanoplasmonic biosensor with extraordinary optical transmission (EOT) effect, one-step sample addition, ASFV antibody was detected within 20 min. The positive antibody showed a satisfactory sensitivity and linear relationship in the dilution ratio of 1:100-1:16000. It was used for the detection of clinical serum samples with a coincidence rate of 96.6%. The measurement results can be automatically analyzed and displayed on a conventional microplate meter computer and connected device. Our detection method can be widely applied in point-of-care testing (POCT) of ASFV antibody in pig farms. IMPORTANCE African swine fever (ASF) is a serious transnational disease caused by the African swine fever virus (ASFV), which is highly contagious in wild boars and domestic pigs. There is currently no available vaccine for ASF; therefore, development efforts are a key priority as ASFV continues to evolve and diversify. The ASF antibody rapid detection platform comprising the nanoplasmonic biosensor with extraordinary optical transmission effect can greatly reduce the detection time and improve detection flux while maintaining detection sensitivity and specificity. The one-step sample addition can effectively avoid cross contamination of samples in the detection process. The detection method provides a solution for the rapid and accurate real-time monitoring of ASF in pig farms.


Subject(s)
African Swine Fever Virus , African Swine Fever , Biosensing Techniques , Swine , Animals , African Swine Fever/diagnosis , African Swine Fever Virus/genetics , Sus scrofa , Nucleic Acid Amplification Techniques
10.
Nat Commun ; 13(1): 4553, 2022 08 05.
Article in English | MEDLINE | ID: mdl-35931666

ABSTRACT

Combining immune checkpoint blockade (ICB) therapy with photodynamic therapy (PDT) holds great potential in treating immunologically "cold" tumors, but photo-generated reactive oxygen species (ROS) can inevitably damage co-administered ICB antibodies, hence hampering the therapeutic outcome. Here we create a ROS-responsive hydrogel to realize the sustained co-delivery of photosensitizers and ICB antibodies. During PDT, the hydrogel skeleton poly(deca-4,6-diynedioic acid) (PDDA) protects ICB antibodies by scavenging the harmful ROS, and at the same time, triggers the gradual degradation of the hydrogel to release the drugs in a controlled manner. More interestingly, we can visualize the ROS-responsive hydrogel degradation by Raman imaging, given the ultrastrong and degradation-correlative Raman signal of PDDA in the cellular silent window. A single administration of the hydrogel not only completely inhibits the long-term postoperative recurrence and metastasis of 4T1-tumor-bearing mice, but also effectively restrains the growth of re-challenged tumors. The PDDA-based ROS-responsive hydrogel herein paves a promising way for the durable synergy of PDT and ICB therapy.


Subject(s)
Neoplasms , Photochemotherapy , Animals , Cell Line, Tumor , Hydrogels , Mice , Neoplasms/drug therapy , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Reactive Oxygen Species/metabolism
11.
Biosens Bioelectron ; 199: 113868, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-34920226

ABSTRACT

COVID-19 vaccination efficacy depends on serum levels of the neutralizing antibodies (NAs) specific to the receptor-binding domain of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Therefore, a high-throughput rapid assay capable of measuring the total SARS-CoV-2 NA level is urgently needed for COVID-19 serodiagnosis, convalescent plasma therapy, vaccine development, and assessment. Here, we developed a novel nanoplasmonic immunosorbent assay (NanoPISA) platform for one-step rapid quantification of SARS-CoV-2 NAs in clinical serum samples for high-throughput evaluation of COVID-19 vaccine effectiveness. The NanoPISA platform enhanced by the use of nanoporous hollow gold nanoparticle coupling was able to detect SARS-CoV-2 NAs with a limit of detection of 0.2 pM within 15 min without washing steps. The one-step NanoPISA for SARS-CoV-2 NA detection in clinical specimens yielded good results, comparable with those obtained in the gold-standard seroneutralization test and the surrogate virus-neutralizing enzyme-linked immunosorbent assay. Collectively, the one-step NanoPISA might be a rapid and high-throughput NA-quantification platform for evaluating the effectiveness of COVID-19 vaccines.


Subject(s)
Biosensing Techniques , COVID-19 , Metal Nanoparticles , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/therapy , COVID-19 Vaccines , Gold , Humans , Immunization, Passive , SARS-CoV-2 , Vaccination , Vaccine Development , Vaccine Efficacy , COVID-19 Serotherapy
12.
Preprint in English | medRxiv | ID: ppmedrxiv-21255838

ABSTRACT

The COVID-19 vaccination efficacy depends on serum production level of the neutralizing IgG antibody (NA) specific to the receptor binding domain of SARS-Cov-2 spike protein. Therefore, a high-throughput rapid assay to measure the total SARS-CoV-2 NA level is urgently needed for COVID-19 serodiagnosis, convalescent plasma therapy, vaccine development, and assessment. Here, we developed a nanoplasmonic immunosorbent assay (NanoPISA) platform for one-step rapid quantification of SARS-CoV-2 NAs in clinical serum samples for high-throughput evaluation of COVID-19 vaccine effectiveness. The NanoPISA platform enhanced by the use of nanoporous hollow gold nanoparticle coupling was able to detect SARS-CoV-2 NAs with a limit of detection of 0.1 ng/mL within 15 min. The one-step NanoPISA for SARS-CoV-2 NA detection in clinical specimens yielded good results, comparable to those obtained in the gold standard seroneutralization test and the surrogate virus neutralizing ELISA. Collectively, our findings indicate that the one-step NanoPISA may offer a rapid and high-throughput NA quantification platform for evaluating the effectiveness of COVID-19 vaccines.

13.
Biosens Bioelectron ; 171: 112685, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33113383

ABSTRACT

The spread of SARS-CoV-2 virus in the ongoing global pandemic has led to infections of millions of people and losses of many lives. The rapid, accurate and convenient SARS-CoV-2 virus detection is crucial for controlling and stopping the pandemic. Diagnosis of patients in the early stage infection are so far limited to viral nucleic acid or antigen detection in human nasopharyngeal swab or saliva samples. Here we developed a method for rapid and direct optical measurement of SARS-CoV-2 virus particles in one step nearly without any sample preparation using a spike protein specific nanoplasmonic resonance sensor. As low as 370 vp/mL were detected in one step within 15 min and the virus concentration can be quantified linearly in the range of 0 to 107 vp/mL. Measurements shown on both generic microplate reader and a handheld smartphone connected device suggest that our low-cost and rapid detection method may be adopted quickly under both regular clinical environment and resource-limited settings.


Subject(s)
Betacoronavirus/isolation & purification , Biosensing Techniques/instrumentation , Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , Point-of-Care Testing , Virion/isolation & purification , Antibodies, Immobilized/chemistry , Biosensing Techniques/economics , COVID-19 , COVID-19 Testing , Clinical Laboratory Techniques/economics , Coronavirus Infections/economics , Equipment Design , Humans , Limit of Detection , Models, Molecular , Pandemics , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/analysis , Time Factors
14.
Preprint in English | bioRxiv | ID: ppbiorxiv-142372

ABSTRACT

The spread of SARS-CoV-2 virus in the ongoing global pandemics has led to infections of millions of people and losses of many lives. The rapid, accurate and convenient SARS-CoV-2 virus detection is crucial for controlling and stopping the pandemics. Diagnosis of patients in the early stage infection are so far limited to viral nucleic acid or antigen detection in human nasopharyngeal swab or saliva samples. Here we developed a method for rapid and direct optical measurement of SARS-CoV-2 virus particles in one step nearly without any sample preparation using a spike protein specific nanoplasmonic resonance sensor. We demonstrate that we can detect as few as 30 virus particles in one step within 15 minutes and can quantify the virus concentration linearly in the range of 103 vp/ml to 106 vp/ml. Measurements shown on both generic microplate reader and a handheld smartphone connected device suggest that our low-cost and rapid detection method may be adopted quickly under both regular clinical environment and resource-limited settings.

15.
JNMA J Nepal Med Assoc ; 54(202): 63-66, 2016.
Article in English | MEDLINE | ID: mdl-27935925

ABSTRACT

INTRODUCTION: Fused or Ankylosed hip is late complication of chronic inflammatory disorder with progressive changes in and around articular as well as periarticular structures with alteration in bio-force line of body which later lead to severe flexion deformity of joint. This not only results decreased movements of hip, it's also increase pain around the hip, back and contralateral hip. METHODS: Retrospectively, all patients aged 18 years or older undergoing THA between June 2006 to June 2012 were reviewed with selection criteria. The five ankylosed hips (three left and two right) with severe flexion deformities which ankylosed spontaneously were successfully converted to THA at time period of 2006 to June 2012. Range of motion, Harris Hip Score and flexion deformity angle at preoperative, postoperative and follow-up periods were used as evaluation. RESULTS: Mean follow up is 42 months. Mean HHS increased from 21.6±4.97 to 81.8±4.02 points with one excellent, two good and two fair cases. The FDA is corrected to mean 8°±10.95 postoperatively and 4°±5.47 at final follow up from 81.6°±4.39 with two hips of 10° residual deformity. Hip ROM is improved as flexion 70° to 100°, adduction 10° to 20°, abduction 10° to 30°, internal rotation 5° to 10° and external rotation 2° to 50° from 0° activity. As complications, one hip had loose prosthesis, two had early postoperative dislocations, one had Deep Vein Thrombosis and one had femoral nerve palsy with quadriceps weakness. CONCLUSIONS: THA is an effective treatment for ankylosed hip with severe flexion deformity although complications are noted more than routine hip arthroplasties.


Subject(s)
Ankylosis/surgery , Arthroplasty, Replacement, Hip , Hip Joint/surgery , Range of Motion, Articular , Adult , Ankylosis/diagnosis , Ankylosis/etiology , Ankylosis/physiopathology , Follow-Up Studies , Hip Joint/physiopathology , Humans , Retrospective Studies , Time Factors , Treatment Outcome
16.
Colloids Surf B Biointerfaces ; 145: 839-844, 2016 Sep 01.
Article in English | MEDLINE | ID: mdl-27315332

ABSTRACT

Zein is a biocompatible corn protein potentially useful in the development of biomaterials. In this study, the deposition of zein on oxygen plasma treated glass cover slips significantly enhanced cell spreading and viability. The mechanism for cellular response to zein coated surfaces was thought to involve the polyglutamine peptides on the zein structure. We hypothesized that zein was a substrate for tissue transglutaminase (tTG), an extracellular enzyme involved in cell-surface interactions. SDS-PAGE results suggested an interaction between zein and tTG, where zein was the glutamine donor. Cross-linking between zein and tTG may be the first step in successful cell adhesion and spreading.


Subject(s)
Membranes, Artificial , Zein/chemistry , Animals , Biocompatible Materials/chemistry , Cell Adhesion/physiology , Cell Line , Cell Movement/physiology , Cell Survival/physiology , Mice , Transglutaminases/metabolism
17.
Cancer Gene Ther ; 21(9): 397-404, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25213664

ABSTRACT

The aim of this study was to investigate the role and mechanism of miR-23a in the regulation of BCR/ABL and to provide a new prognostic biomarker for chronic myeloid leukemia (CML). The expression levels of miR-23a and BCR/ABL were assessed in 42 newly diagnosed CML patients, 37 CML patients in first complete remission and 25 healthy controls. Quantitative real-time PCR, western blot analysis and colony formation assay were used to evaluate changes induced by overexpression or inhibition of miR-23a or BCR/ABL. MiR-23a mimic or negative control mimic was transfected into a CML cell line (K562) and two lung cancer cell lines (H157 and SKMES1) using Lipofectamine 2000, and the cells were used for real-time reverse transcription-PCR (RT-PCR) and western blot analysis. We found that the downregulation of miR-23a expression was a frequent event in both leukemia cell lines and primary leukemic cells from patients with de novo CML. The microarray results showed that most of the CML patients expressed high levels of BCR/ABL and low levels of miR-23a. Real-time RT-PCR and western blot analysis showed that the BCR/ABL levels in miR-23a-transfected cells were lower than those in the control groups. Ectopic expression of miR-23a in K562 cells led to cellular senescence. Moreover, when K562 cells were treated with 5-aza-2'-deoxycytidine, a DNA methylation inhibitor, BCR/ABL expression was upregulated, which indicates epigenetic silencing of miR-23a in leukemic cells. BCR/ABL and miR-23a expressions were inversely related to CML, and BCR/ABL expression was regulated by miR-23a in leukemic cells. The epigenetic silencing of miR-23a led to derepression of BCR/ABL expression, and consequently contributes to CML development and progression.


Subject(s)
Fusion Proteins, bcr-abl/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , MicroRNAs/genetics , RNA Interference , 3' Untranslated Regions , Adolescent , Adult , Aged , Azacitidine/pharmacology , Bone Marrow/metabolism , Bone Marrow/pathology , Bone Marrow Cells/metabolism , Bone Marrow Cells/pathology , Cell Line, Tumor , Cellular Senescence/genetics , Female , Gene Expression Regulation, Leukemic/drug effects , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism , Male , Matrix Metalloproteinase 9/metabolism , Middle Aged , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt , Signal Transduction , Young Adult
18.
Z Naturforsch C J Biosci ; 65(5-6): 387-90, 2010.
Article in English | MEDLINE | ID: mdl-20653241

ABSTRACT

Extraction of mannan oligosaccharides from the yeast cell wall and methods of deproteinization were studied. We extracted crude mannan oligosaccharides by the dilute alkali-Sevage method. The percentages of deproteinization and mannan oligosaccharide loss were compared as indexes using the Sevage method, trichloroacetic acid method, and hydrochloric acid method. The results showed that the hydrochloric acid method exhibited the highest percentage of deproteinization, but only a little higher percentage of mannan oligosaccharide loss than the other two methods.


Subject(s)
Mannans/chemistry , Oligosaccharides/chemistry , Hydrochloric Acid , Indicators and Reagents , Oligosaccharides/isolation & purification , Proteins/isolation & purification , Spectrophotometry, Infrared , Trichloroacetic Acid
19.
Lab Chip ; 9(23): 3360-3, 2009 Dec 07.
Article in English | MEDLINE | ID: mdl-19904401

ABSTRACT

In this paper, we present a method combining surface-enhanced Raman scattering (SERS) spectroscopy to detect biomolecules in a label-free way with an electrokinetic preconcentration technique (electrophoresis) to amplify biomolecular signals at low concentrations. A constant electric field is applied to charged biomolecules in solution, attracting them to an oppositely charged electrode, which is also used as a SERS substrate. Within 5 min, we observed that the SERS signal of 10 fM adenine was amplified to the level of the signal of non-preconcentrated 1 microM adenine (sensitivity improvement by 8 orders of magnitude) and the method was effective over a wide range of concentrations (10 fM to 1 microM). The signals were further amplified under stronger electric field and longer application: The increase of the signal intensity was observed to be 51 times at -0.6 V cm(-1) after 25 min. The effectiveness of this method allows the creation of label-free, target-specific, and highly sensitive monitoring applications.


Subject(s)
Adenine/analysis , Electrophoresis/methods , Spectrum Analysis, Raman/methods , Sensitivity and Specificity , Surface Properties
20.
Proc Natl Acad Sci U S A ; 106(11): 4085-9, 2009 Mar 17.
Article in English | MEDLINE | ID: mdl-19251659

ABSTRACT

Multimodality imaging based on complementary detection principles has broad clinical applications and promises to improve the accuracy of medical diagnosis. This means that a tracer particle advantageously incorporates multiple functionalities into a single delivery vehicle. In the present work, we explore a unique combination of MRI and photoacoustic tomography (PAT) to detect picomolar concentrations of nanoparticles. The nanoconstruct consists of ferromagnetic (Co) particles coated with gold (Au) for biocompatibility and a unique shape that enables optical absorption over a broad range of frequencies. The end result is a dual-modality probe useful for the detection of trace amounts of nanoparticles in biological tissues, in which MRI provides volume detection, whereas PAT performs edge detection.


Subject(s)
Magnetic Resonance Imaging/methods , Metal Nanoparticles , Tomography/methods , Cobalt , Diagnostic Imaging/methods , Gold , Sensitivity and Specificity
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