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1.
Chembiochem ; 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913537

RESUMO

Toehold switch sensors represent a classic of new advances that allow specific targets triggering in-situ expression of protein reporter. Even if holding unique advantages of label-free and high portability, they generally require repeated sequence design, high cost and laborious optimization of toehold switch sequence according to different targets. To further simplify the sensing process and improve the practicability, we innovatively introduce a dual-step pre-transduction upon traditional toehold switch sensor. Through two successive toehold-mediated strand displacement reactions, in respective, initiated by linear and associative trigger, different DNAs, RNAs, or ligands of functional nucleic acids can be generally transduced into the input of one well-performed toehold switch sensor. This advance largely increases the target range. Furthermore, the whole process is signal-on, homogeneous, and free of any sophisticated operation such as probe labelling, separation, and reconstruction of toehold switch, being even promising and practical in portable or point-of-care assays.

2.
J Chromatogr Sci ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31746330

RESUMO

The differential constituents in leaves, stems and roots of Polygonum multiflorum Thunb. were analyzed by ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC/ESI-Q-TOF-MS) and by multivariate statistical analysis. The established extraction and analysis method showed relative standard deviations (RSDs) for intra-day precision of less than 3.40%, for repeatability of less than 4.06% and for stability of less than 5.10%. Principal component analysis and orthogonal projections to latent structures discriminant analysis of the UPLC/ESI-Q-TOF-MS data showed good ability to classify the leaves, stems and roots of P. multiflorum Thunb. The differential constituents, such as stilbenes, polygoacetophenoside, flavonoids and anthraquinones, accounting for variations between the leaves, stems and roots, were filtered through the variable importance in projection values and were further identified by elemental composition analysis, mass fragmentation data and retention times of available standards. Differences between the chemical compositions in the leaves, stems and roots of P. multiflorum Thunb. were closely related to their various therapeutic effects. This UPLC/ESI-Q-TOF-MS-based analytical strategy could be further utilized to evaluate the overall quality of traditional Chinese medicines and their differences of chemical constituents in different parts of the plant and/or in the plants of different geographical locations.

3.
Anal Chim Acta ; 1079: 171-179, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31387708

RESUMO

Recent study proves that the combination of loop mediated isothermal nucleic acid amplification (LAMP) with one-step strand displacement (OSD) is of great help to improve the sequence specificity during genetic detection. However, because OSD is incapable of signal amplification, the signal-to-noise ratio or the observable signal change may be usually not significant enough to satisfy practical usage. With the purpose to overcome this challenge, herein a more advanced and practical sensing principle is developed with the OSD replaced by an amplifiable nucleic acid circuit, hybridization chain reaction (HCR). The very contagious norovirus (NoV) was employed as the model target. Compared with LAMP-OSD, the LAMP-HCR can detect as few as 30 copies of NoV gene in 2% fecal samples with significantly enlarged signal change and signal-to-background ratio. Therefore, more reliable detection is achieved. Moreover, due to the high compatibility of HCR, the final LAMP-HCR products can be flexibly transduced into different types of readouts, including fluorescence, flow cytometer (FCM) and even a personal glucose meter (PGM). This further enlarges the operating environments for the detection from hospital labs, bedsides, to potential off-the-shelf devices in local pharmacies. Especially when using FCM or PGM, with the assistance of magnetic beads (MBs), the detection shows even higher tolerance capability to complicated biological matrices.

4.
Cryobiology ; 89: 14-20, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31276669

RESUMO

This study determined the changes in pollen viability of 102 species/cultivars of ornamental plants (affiliated to 32 genera of 14 families) following long-term liquid nitrogen storage in a cryopreservation pollen bank. The goal was to provide information on the safety and stability of pollen cryopreservation technology. Fresh pollen at the time of storage was used as the control, and the study examined the pollen viability of ornamental plants cryopreserved for 8, 9, or 10 years. The results show that pollen of the 102 species/cultivars in the cryopreservation pollen bank retained viability ranging from 1% to 58%, After long-term storage there were changes in viability: 11.76% (12 species/cultivars) had increased viability, 16.67% (17 species/cultivars) had stable viability, and the viability of 71.57% (73 species/cultivars) showed a decreasing trend.

5.
Nanoscale ; 11(21): 10339-10347, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31107481

RESUMO

Recent advances have proven solid-state nanopores as a powerful analysis platform that enables label-free and separation-free single-molecule analysis. However, the relatively low resolution still limits its application because many chemicals or targets with small sizes could not be recognized in a label-free condition. In this paper, we provide a possible solution that uses solid-state nanopores for small species signaling via the transition of huge DNA assembly products. DNAzyme responding to metal ions and the hybridization chain reaction (HCR) generating nanopore-detectable dsDNA concatamers are used as the transition model set. By the two-step DNAzyme-HCR transition, Pb2+ that was too tiny to be sensed was successfully recognized by the nanopore. The whole process happened in a completely homogeneous solution without any chemical modification. During condition optimization, we also discussed one possible application challenge that may affect the HCR signal-background distinction. Solid-state nanopores provide a potential solution to this challenge due to its ability to profile product length or even 3D structure information.


Assuntos
DNA Catalítico/química , Chumbo/análise , Metais , Nanoporos , Ribonucleases/química , Transdução de Sinais , Hibridização de Ácido Nucleico
6.
Chem Sci ; 10(7): 1953-1961, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30881624

RESUMO

Recent advances have proven that using solid-state nanopores is a promising single molecular technique to enrich the DNA assembly signaling library. Other than using them for distinguishing structures, here we innovatively adapt solid-state nanopores for use in analyzing assembly mixtures, which is usually a tougher task for either traditional characterization techniques or nanopores themselves. A trigger induced DNA step polymerization (SP-CHA), producing three-way-DNA concatemers, is designed as a model. Through counting and integrating the translocation-induced current block when each concatemer passes through a glass conical glass nanopore, we propose an electrophoresis-gel like, but homogeneous, quantitative method that can comprehensively profile the "base-pair distribution" of SP-CHA concatemer mixtures. Due to the higher sensitivity, a number of super long concatemers that were previously difficult to detect via gel electrophoresis are also revealed. These ultra-concatemers, longer than 2 kbp, could provide a much enhanced signal-to-noise ratio for nanopores and are thus believed to be more accurate indicators for the existence of a trigger, which may be of benefit for further applications, such as molecular machines or biosensors.

7.
Chem Sci ; 9(3): 760-769, 2018 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-29629146

RESUMO

The polymerase chain reaction and many isothermal amplifications are able to achieve super gene amplification. Unfortunately, most commonly-used transduction methods, such as dye staining and Taqman-like probing, still suffer from shortcomings including false signals or difficult probe design, or are incompatible with multi-analysis. Here a universal and rational gene detection strategy has been established by translating isothermal amplicons to enzyme-free strand displacement circuits via three-way junction-based remote transduction. An assistant transduction probe was imported to form a partial hybrid with the target single-stranded nucleic acid. After systematic optimization the hybrid could serve as an associative trigger to activate a downstream circuit detector via a strand displacement reaction across the three-way junction. By doing so, the detection selectivity can be double-guaranteed through both amplicon-transducer recognition and the amplicon-circuit reaction. A well-optimized circuit can be immediately applied to a new target detection through simply displacing only 10-12 nt on only one component, according to the target. More importantly, this property for the first time enables multi-analysis and logic-analysis in a single reaction, sharing a single fluorescence reporter. In an applicable model, trace amounts of Cronobacter and Enterobacteria genes have been clearly distinguished from samples with no bacteria or one bacterium, with ultra-high sensitivity and selectivity.

8.
Anal Chem ; 90(1): 814-820, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29172452

RESUMO

Recent advances have shown increasing designs of nucleic acid organizations via controlling the thermodynamics and kinetics of oligonucleotides. Nevertheless, deeper understanding and further applications of these DNA nanotechnologies are majorly hampered by the lack of effective analytical methodologies that are competent enough to investigate them. To deliver a potential solution, here we developed an innovative exploration that employed the emerging nanopore technique to characterize DNA organization at the single-molecule level and in completely homogeneous condition without covalent modification. With the help of counting and profiling the translocation-induced current drop of a DNA assembly structure passing through a conical glass nanopore (CGN), we have directly verified the formation of the individual double-helix concatemer generated from our model, hybridization chain reaction (HCR). Due to the ultrasensitivity of the nanopore technology, those concatemers that were difficult to observe on a conventional electrophoresis image were brought to light. The translocation duration time also provided the approximate length and folding information for the concatemers. These advantages were proven also applicable to structures with more sophisticated folding behaviors. Eventually, when coupling with an upstream reaction, CGN was further turned to a universal detector that was capable of even detecting other nucleic acid organization behaviors as well as targets that were unable to generate huge products. All of these results are expected to promote deeper study and applications of the nanopore technique in the field of nucleic acid nanotechnology.


Assuntos
DNA Concatenado/química , Vidro/química , Nanoporos , Oligodesoxirribonucleotídeos/química , Hibridização de Ácido Nucleico
9.
ACS Sens ; 3(1): 54-58, 2018 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-29250951

RESUMO

Recently, molecular keypad locks have received increasing attention. As a new subgroup of smart biosensors, they show great potential for protecting information as a molecular security data processor, rather than merely molecular recognition and quantitation. Herein, label-free electrochemically transduced Ag+ and cysteine (Cys) sensors were developed. A molecular keypad lock model with reset function was successfully realized based on the balanced interaction of metal ion with its nucleic acid and chemical ligands. The correct input of "1-2-3" (i.e., "Ag+-Cys-cDNA") is the only password of such molecular keypad lock. Moreover, the resetting process of either correct or wrong input order could be easily made by Cys, buffer, and DI water treatment. Therefore, our system provides an even smarter system of molecular keypad lock, which could inhibit illegal access of unauthorized users, holding great promise in information protection at the molecular level.


Assuntos
Técnicas Biossensoriais/instrumentação , Segurança Computacional/instrumentação , DNA/química , Técnicas Eletroquímicas , Metais/química
10.
Angew Chem Int Ed Engl ; 56(4): 992-996, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-27990727

RESUMO

The detection of nucleic acid biomarkers for point-of-care (POC) diagnostics is currently limited by technical complexity, cost, and time constraints. To overcome these shortcomings, we have combined loop-mediated isothermal amplification (LAMP), programmable toehold-mediated strand-exchange signal transduction, and standard pregnancy test strips. The incorporation of an engineered hCG-SNAP fusion reporter protein (human chorionic gonadotropin-O6 -alkylguanine-DNA alkyltransferase) led to LAMP-to-hCG signal transduction on low-cost, commercially available pregnancy test strips. Our assay reliably detected as few as 20 copies of Ebola virus templates in both human serum and saliva and could be adapted to distinguish a common melanoma-associated SNP allele (BRAF V600E) from the wild-type sequence. The methods described are completely generalizable to many nucleic acid biomarkers, and could be adapted to provide POC diagnostics for a range of pathogens.


Assuntos
Técnicas de Amplificação de Ácido Nucleico , Ácidos Nucleicos/análise , Testes de Gravidez , Biomarcadores/análise , Feminino , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Gravidez
11.
Sci Rep ; 6: 36605, 2016 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-27812041

RESUMO

Catalytic hairpin assembly (CHA) is one of the most promising nucleic acid amplification circuits based on toehold-mediated strand exchange reactions. But its performance is usually ruined by fluctuated environmental temperatures or unexpected self-structures existing in most real-world targets. Here we present an amide-assistant mechanism that successfully reduces the prevalence of these problems for CHA and maximizes its thermo- and structure- buffering abilities. Such an organic amide-promoted CHA (shortened as OHT-CHA) can unprecedentedly amplify through 4 °C to 60 °C without rebuilding sequences or concerning target complexity. We are then for the first time able to employ it as a direct and universal signal booster for loop mediated isothermal reaction (LAMP). LAMP is one of the most promising point-of-care (POC) gene amplifiers, but has been hard to detect precisely due to structured products and haunted off-target amplicons. OHT-CHA guarantees a significant and reliable signal for LAMP reaction amplified from as little as 10-19 M virus gene. And one single set of OHT-CHA is qualified to any detection requirement, either in real-time at LAMP running temperature (~60 °C), or at end-point on a POC photon counter only holding environmental temperatures fluctuating between 4 °C to 42 °C.


Assuntos
Técnicas de Diagnóstico Molecular/métodos , Ácidos Nucleicos/química , Técnicas de Diagnóstico Molecular/normas , Conformação de Ácido Nucleico , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Temperatura Ambiente
12.
Chem Commun (Camb) ; 52(88): 13043-13046, 2016 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-27757452

RESUMO

We report a new nucleic acid sensing strategy through an intelligent design of spatial organization based reciprocal switching of catalytic hairpin assembly (CHA). The so-called SORS-CHA not only turns a well-designed CHA circuit into a relatively universal detector for any targeting sequence, but also guarantees a much enhanced signal resolution and a believability to minimize the misreading induced by unexpected signal drifts. With more trustworthy results, but a simpler sequence design, nucleic acid circuits could become competitive in real-world applications.


Assuntos
Técnicas Biossensoriais/métodos , DNA de Cadeia Simples/química , Nanoestruturas/química , Hibridização de Ácido Nucleico , Ácidos Nucleicos/química , Catálise , Humanos , Conformação de Ácido Nucleico
13.
Int J Mol Med ; 38(1): 210-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27247107

RESUMO

Renal ischemia-reperfusion (I/R) injury is associated with high morbidity and mortality as there is currently no available effective therapeutic strategy with which to treat this injury. Thus, the aim of this study was to investigate the potential protective effects of brazilin, a major active component of the Chinese medicine Caesalpinia sappan L., against renal I/R injury in vitro and in vivo. Rats were subjected to removal of the right kidney and I/R injury to the left kidney (ischemia for 45 min followed by reperfusion for 24 h). Treatment with brazilin (30 mg/kg, administered intravenously at 30 min prior to ischemia) led to the reversal of I/R-induced changes in serum creatinine (Scr) and blood urea nitrogen (BUN) levels, and also attenuated the histopathological damage induced by I/R. Furthermore, TUNEL assay revealed that brazilin reduced cell necrosis, and significantly decreased the expression of tumor necrosis factor (TNF)-α and interleukin (IL)-1ß in renal tissue. Moreover, HK-2 cells were used in order to elucidate the mechanisms responsible for the protective effects of brazilin. The levels of phosphorylated IκBα and the nuclear translocation of nuclear factor-κB (NF-κB) were all evidently decreased by brazilin. These findings suggested that pre-treatment with brazilin protects against I/R-induced renal damage and suppresses the inflammatory response by inhibiting the activation of the NF-κB signaling pathway.


Assuntos
Benzopiranos/uso terapêutico , Rim/irrigação sanguínea , NF-kappa B/metabolismo , Substâncias Protetoras/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais , Animais , Apoptose/efeitos dos fármacos , Benzopiranos/química , Benzopiranos/farmacologia , Humanos , Inflamação/patologia , Precondicionamento Isquêmico , Rim/efeitos dos fármacos , Rim/patologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/patologia , Masculino , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Transdução de Sinais/efeitos dos fármacos
14.
Oncotarget ; 7(23): 35257-69, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27153552

RESUMO

Hepatocellular carcinoma (HCC) cells rapidly switch their energy source from oxidative phosphorylation to glycolytic metabolism in order to efficiently proliferate. However, the molecular mechanisms responsible for this switch remain unclear. In this study, we found that miR-592 was frequently downregulated in human HCC tissues and cell lines, and its downregulation was closely correlated with aggressive clinicopathological features and poor prognosis of HCC patients. Overexpression of miR-592 inhibited aerobic glycolysis and proliferation in HCC cells in vitro. Conversely, knockdown of miR-592 promoted HCC growth in both subcutaneous injection and orthotopic liver tumor implantation models in vivo. Mechanistically, miR-592 downregulation in human HCCs was correlated with an upregulation of WD repeat and SOCS box containing 1 (WSB1). We further showed that miR-592 directly binds to the 3'-UTR of the WSB1 gene, thus disrupting hypoxia inducible factor-1α (HIF-1α) protein stabilization. In turn, overexpression of WSB1 in HCC cells rescued decreased HIF-1α expression, glucose uptake, and HCC growth induced by miR-592. Collectively, our clinical data and functional studies suggest that miR-592 is a new robust inhibitor of the Warburg effect and a promising therapeutic target for HCC treatment.


Assuntos
Carcinoma Hepatocelular/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Proteínas/metabolismo , Animais , Biomarcadores Tumorais/análise , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Glicólise/fisiologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos SCID , Prognóstico
15.
Anal Chem ; 88(4): 2250-7, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26750592

RESUMO

During the past decade, aptasensors have largely been designed on the basis of the notion that ligand-modulated equilibration between aptamer conformations could be exploited for sensing. One implementation of this strategy has been to denature the aptamer with an antisense oligonucleotide, wait for dissociation of the antisense oligonucleotide, and stabilize the folded, signaling conformer with a ligand. However, there is a large kinetic barrier associated with releasing the oligonucleotide from the aptamer to again obtain an active, binding conformation. If the length of the antisense oligonucleotide is decreased to make dissociation from the aptamer more favorable, higher background signals are observed. To improve the general methodology for developing aptasensors, we have developed a novel and robust strategy for aptasensor design in which an oligonucleotide kinetically competes with the ligand for binding rather than having to be released from a stable duplex. While the oligonucleotide can induce conformational change, it initially chooses between the aptamer and a molecular beacon (MB), a process that does not require a lengthy pre-equilibration. Using an anti-ricin aptamer as a starting point, we developed a "competitive" aptasensor with a measured limit of detection (LOD) of 30 nM with an optical readout and as low as 3 nM for ricin toxin A-chain (RTA) detection on an electrochemical platform.


Assuntos
Aptâmeros de Nucleotídeos/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Oligonucleotídeos Antissenso/química , Ligação Competitiva , Técnicas Eletroquímicas , Cinética , Ligantes , Limite de Detecção , Sondas Moleculares/análise , Sondas Moleculares/química , Ricina/análise , Ricina/química , Termodinâmica
16.
Diab Vasc Dis Res ; 13(2): 137-44, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26607798

RESUMO

We have previously reported that advanced glycation end products activated Rho-associated protein kinase and p38 mitogen-activated protein kinase, causing endothelial hyperpermeability. However, the mechanisms involved were not fully clarified. Here, we explored the role of myosin light chain kinase in advanced glycation end product-induced endothelial hyperpermeability. Myosin light chain phosphorylation significantly increased by advanced glycation end products in endothelial cells in a time- and dose-dependent manner, indicating that myosin light chain phosphorylation is involved in the advanced glycation end product pathway. Advanced glycation end products also induced myosin phosphatase-targeting subunit 1 phosphorylation, and small interfering RNA knockdown of the receptor for advanced glycation end products, or blocking myosin light chain kinase with its inhibitor, ML-7, or small interfering RNA abated advanced glycation end product-induced myosin light chain phosphorylation. Advanced glycation end product-induced F-actin rearrangement and endothelial hyperpermeability were also diminished by inhibition of receptor for advanced glycation end product or myosin light chain kinase signalling. Moreover, inhibiting myosin light chain kinase with ML-7 or blocking receptor for advanced glycation end product with its neutralizing antibody attenuated advanced glycation end product-induced microvascular hyperpermeability. Our findings suggest a novel role for myosin light chain and myosin light chain kinase in advanced glycation end product-induced endothelial hyperpermeability.


Assuntos
Permeabilidade Capilar/fisiologia , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Cadeias Leves de Miosina/metabolismo , Quinase de Cadeia Leve de Miosina/metabolismo , Azepinas/metabolismo , Células Cultivadas , Humanos , Naftalenos/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Transdução de Sinais/fisiologia
17.
BMC Health Serv Res ; 16(1): 210, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-28340611

RESUMO

BACKGROUND: Stigma is a major issue across various society and cultures, and few studies focus on the perception of stigma by Chinese patients with schizophrenia. In the current cross-sectional study, we sought to assess the extent of internalized stigma among outpatients with schizophrenia in China and to investigate whether education level correlated with the experience of stigma. METHODS: Outpatients with schizophrenia were evaluated using the brief psychosis rating scale (BPRS), the positive and negative syndrome scale (PANSS), the clinical global impression-severity of illness (CGI-SI) scale and the Stigma Scale for Mental Illness (SSMI 2C). Patients were categorized into the high education and low education group according to their educational levels. RESULTS: One hundred thirty-three subjects were included in the study. Their mean course of illness was 4.32 ± 6.14 years (range, 1 month to 15 years). Their mean BPRS score was 19.87 ± 5.46, their mean PANSS score was 44.11 ± 13.1, and their mean CGI-SI score was 2.22 ± 0.81. In addition, the mean SSMI 2C score of the high education group (7.15 ± 0.98) was markedly higher than that of the low education group (5.75 ± 0.79, P < 0.05). The mean domain I score of the high education group (2.30 ± 0.76) was comparable to that of the low education group (2.07 ± 0.78, P > 0.05). The mean domain II score of the high education group (2.42 ± 0.96) was markedly higher than that of the low education group (2.01 ± 0.79, P < 0.05). Moreover, the mean domain III score of the high education group (2.43 ± 0.79) was significantly higher than that of the low education group (1.67 ± 0.77, P < 0.05). CONCLUSIONS: Education level impacts on the perception of stigma by patients with schizophrenia and more psycho-education should be done to improve patients' knowledge about schizophrenia.


Assuntos
Atitude Frente a Saúde , Psicologia do Esquizofrênico , Estigma Social , Adulto , Idoso , Antipsicóticos/uso terapêutico , Grupo com Ancestrais do Continente Asiático/etnologia , China/etnologia , Estudos Transversais , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais/psicologia , Percepção , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/psicologia , Esquizofrenia/tratamento farmacológico , Esquizofrenia/etnologia , Adulto Jovem
18.
Int J Clin Exp Pathol ; 8(9): 11495-502, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26617881

RESUMO

Intracranial large artery atherosclerosis (ILAA) is a major cause of ischemic cerebrovascular disease. The aim of this study was to investigate whether the levels of circulating dendritic cell precursors (DCP) could reflect the severity of intracranial large artery atherosclerosis (ILAA). For this purpose, a series of angiography were taken to determine the severity and extent of coronary artery and intracranial large artery stenosis, and flow cytometry were taken to determine the levels of circulating mDC precursors and pDC precursors in patients with severe intracranial large artery atherosclerosis (ILAA) (n = 101) and mild intracranial large artery atherosclerosis (ILAA) (n = 123) according to the angiography. Circulating mDC precursors were lower in patients with severe intracranial large artery atherosclerosis (ILAA) than in mild intracranial large artery atherosclerosis (ILAA) (P < 0.05), but circulating pDC precursors were not significant differences (P > 0.05). According to these data, circulating mDC precursors could predict the severity of ILAA, which also could be able to reflect the severity of ILAA.


Assuntos
Células Dendríticas , Arteriosclerose Intracraniana/sangue , Arteriosclerose Intracraniana/patologia , Células-Tronco , Adulto , Idoso , Contagem de Células , Angiografia Cerebral , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
19.
Iran J Radiol ; 12(3): e14142, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26557267

RESUMO

BACKGROUND: Inferior vena cava filters (IVCF) are frequently used for preventing pulmonary embolism (PE) following deep venous thromboembolism. OBJECTIVES: The present study was designed to investigate whether IVCF could prevent or impede the occurrence of bone cement implantation syndrome (BCIS), since PE is considered as the central mechanism of BCIS. MATERIALS AND METHODS: Fifteen sheep were divided into three groups: bone cement free (BCF) group, cement implantation (CI) group and IVCF group. In all the groups, an osteotomy proximal to the greater trochanter of left femur was carried out. In BCF group, the femoral canal was not reamed out or packed with any bone cement. In CI and IVCF groups, the left femoral canals were packed with bone cement, to simulate the cementing procedures carried out in hip replacement. An OptEase(®) filter was placed and released in inferior vena cava, prior to packing cement in the femoral canal in IVCF group, while the IVCF was not released in the CI group. The BCF group was considered as control. RESULTS: Systolic blood pressure (SBP), saturation of oxygen (SaO2) and partial pressure of carbon dioxide (PaCO2) declined significantly 10 min after the bone cement packing, in CI group, compared to those in BCF group. This was accompanied by a rise in the arterial pH. However, IVCF prevented those changes in the CI group. On ultrasonography, there were dotted echoes in right atrium in the CI group, after bone cement packing, while such echoes were hardly seen in the IVCF group. CONCLUSION: This study demonstrates that IVCF could prevent BCIS effectively, and, as a corollary, suggests that PE represents the leading cause of the constellation of BCIS symptoms.

20.
Sci Rep ; 5: 11039, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-26050646

RESUMO

Strand exchange nucleic acid circuitry can be used to transduce isothermal nucleic acid amplification products into signals that can be readable on an off-the-shelf glucometer. Loop-mediated isothermal amplification (LAMP) is limited by the accumulation of non-specific products, but nucleic acid circuitry can be used to probe and distinguish specific amplicons. By combining this high temperature isothermal amplification method with a thermostable invertase, we can directly transduce Middle-East respiratory syndrome coronavirus and Zaire Ebolavirus templates into glucose signals, with a sensitivity as low as 20-100 copies/µl, equating to atto-molar (or low zepto-mole). Virus from cell lysates and synthetic templates could be readily amplified and detected even in sputum or saliva. An OR gate that coordinately triggered on viral amplicons further guaranteed fail-safe virus detection. The method describes has potential for accelerating point-of-care applications, in that biological samples could be applied to a transducer that would then directly interface with an off-the-shelf, approved medical device.


Assuntos
Proteínas de Bactérias/química , Ebolavirus/química , Glucose/análise , Técnicas de Amplificação de Ácido Nucleico , Vírus da SARS/química , beta-Frutofuranosidase/química , Ebolavirus/genética , Vírus da SARS/genética
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