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1.
Anal Chem ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896549

RESUMO

Circulating microRNAs (miRNAs) have recently emerged as noninvasive disease biomarkers. Quantitative detection of circulating miRNAs could offer significant information for clinical diagnosis due to its significance in the development of biological processes. In response to the current challenges of circulating miRNA detection, we introduce a sensitive, selective, and versatile circulating miRNA detection strategy using terminal deoxynucleotidyl transferase (TdT)-catalyzed RNA-primed DNA polymerization (TCRDP) coupled with semiarbitrary qPCR (SAPCR). Semiarbitrary qPCR was first developed here to detect long fragment targets with only a short-known sequence or to detect a short fragment target after extension with terminal transferase. Besides, the subsequent results show that TdT has a preference for RNA, particularly for extending RNAs with purine-rich and unstructured ends. Consequently, utilizing this assay, we have successfully applied it to the quantitative analysis of circulating miR-122 in animal models, a sensitive and informative biomarker for drug-induced liver injury, and as low as 200 zmol of the target is detected with desirable specificity and sensitivity, indicating that the TCRDP-SAPCR can offer a promising platform for nucleic acids analysis.

2.
Neurocrit Care ; 40(2): 506-514, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37316678

RESUMO

BACKGROUND: Fibrinogen has been identified as a modulator of the coagulation and inflammatory process. There is uncertainty about the relationship between the dynamic profile of fibrinogen levels and its impact on clinical outcomes in patients with acute ischemic stroke treated with endovascular thrombectomy. METHODS: We consecutively enrolled patients with acute ischemic stroke who underwent endovascular thrombectomy. Fibrinogen was measured on admission and during hospitalization. The change in fibrinogen (Δfibrinogen) was calculated as the highest follow-up fibrinogen minus admission fibrinogen, with a positive Δfibrinogen indicating an increase in fibrinogen level. Functional outcome was assessed by the modified Rankin Scale at 3 months. Poor outcome was defined as modified Rankin Scale > 2. RESULTS: A total of 346 patients were included (mean age 67.4 ± 13.6 years, 52.31% men). The median fibrinogen on admission was 2.77 g/L (interquartile range 2.30-3.39 g/L). The median Δfibrinogen was 1.38 g/L (interquartile range 0.27-2.79 g/L). Hyperfibrinogenemia (> 4.5 g/L) on admission was associated with an increased risk of poor outcome [odds ratio (OR) 5.93, 95% confidence interval (CI) 1.44-24.41, p = 0.014]. There was a possible U-shaped association of Δfibrinogen with outcomes, with an inflection point of - 0.43 g/L (p = 0.04). When Δfibrinogen was < - 0.43 g/L, a higher decrease in fibrinogen (lower Δfibrinogen value) was associated with a higher risk of poor outcome (OR 0.22, 95% CI 0.02-2.48, p = 0.219). When Δfibrinogen was > - 0.43 g/L, the risk of poor outcome increased with increasing fibrinogen (OR 1.27, 95% CI 1.04-1.54, p = 0.016). CONCLUSIONS: In patients with endovascular thrombectomy, hyperfibrinogenemia on admission was associated with poor functional outcomes at 3 months, whereas Δfibrinogen was associated with poor 3-month outcomes in a possible U-shaped manner.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/efeitos adversos , Fibrinogênio , AVC Isquêmico/cirurgia , AVC Isquêmico/complicações , Trombectomia , Resultado do Tratamento
3.
Langmuir ; 38(45): 13857-13869, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36322957

RESUMO

The powder process is dynamic at the microscale level. Due to the capillary effect, the viscous attraction of the liquid phase between particles alters the strength and stability of wet granular materials. In this paper, experiments on the rupture behavior of the funicular liquid bridge between three rigid spheres have been presented. The results show that the peak force and rupture distance of the funicular liquid bridges are affected by the size and relative position of the spheres, volume and viscosity of the liquid, and separation rate; the coalescence of the liquid bridges causes a decrease in peak force and an increase in rupture distance, and the rupture distance shows a nonmonotonic functional correlation with the separation rate. Finally, an empirical equation of the correlation between the rupture distance and liquid volume is proposed, whose rationality is verified by comparing it with the results of the existing models.

4.
BMC Med Res Methodol ; 22(1): 15, 2022 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-35026998

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has posed a significant influence on public mental health. Current efforts focus on alleviating the impacts of the disease on public health and the economy, with the psychological effects due to COVID-19 relatively ignored. In this research, we are interested in exploring the quantitative characterization of the pandemic impact on public mental health by studying an online survey dataset of the United States. METHODS: The analyses are conducted based on a large scale of online mental health-related survey study in the United States, conducted over 12 consecutive weeks from April 23, 2020 to July 21, 2020. We are interested in examining the risk factors that have a significant impact on mental health as well as in their estimated effects over time. We employ the multiple imputation by chained equations (MICE) method to deal with missing values and take logistic regression with the least absolute shrinkage and selection operator (Lasso) method to identify risk factors for mental health. RESULTS: Our analysis shows that risk predictors for an individual to experience mental health issues include the pandemic situation of the State where the individual resides, age, gender, race, marital status, health conditions, the number of household members, employment status, the level of confidence of the future food affordability, availability of health insurance, mortgage status, and the information of kids enrolling in school. The effects of most of the predictors seem to change over time though the degree varies for different risk factors. The effects of risk factors, such as States and gender show noticeable change over time, whereas the factor age exhibits seemingly unchanged effects over time. CONCLUSIONS: The analysis results unveil evidence-based findings to identify the groups who are psychologically vulnerable to the COVID-19 pandemic. This study provides helpful evidence for assisting healthcare providers and policymakers to take steps for mitigating the pandemic effects on public mental health, especially in boosting public health care, improving public confidence in future food conditions, and creating more job opportunities. TRIAL REGISTRATION: This article does not report the results of a health care intervention on human participants.


Assuntos
COVID-19 , Pandemias , Humanos , Saúde Mental , SARS-CoV-2 , Instituições Acadêmicas , Estados Unidos/epidemiologia
5.
J Arthroplasty ; 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36122691

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

6.
J Nanosci Nanotechnol ; 14(5): 3707-10, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24734618

RESUMO

Tetragonal phase NaYW2O8:Yb3+/Ho3+ nanocrystals were successfully synthesized using a hydrothermal method with a subsequent calcination treatment. Under 980 nm excitation, the 5S2/5F4 --> 5I8 and 5F5 --> 5I8 emissions were observed. The relative intensity of the 5F5 --> 5I8 to the 5S2/5F4 -->5I8 in the samples increased with increasing the pH values of the resultant solutions. The CIE coordinates of the upconversion luminescence were (0.43, 0.54), (0.41, 0.55), (0.40, 0.56), (0.39, 0.54), (0.37, 0.49), (0.35, 0.44), and (0.33, 0.37) for the samples prepared at pH = 7, 8, 9, 10, 11, 13, and 14, respectively. In addition, the upconversion mechanism was also investigated.

7.
Micromachines (Basel) ; 14(3)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36984929

RESUMO

Nowadays, the impact ionization coefficient in the avalanche breakdown theory is obtained using 1-D PN junctions or SBDs, and is considered to be a constant determined by the material itself only. In this paper, the impact ionization coefficient of silicon in a 2D lateral power device is found to be no longer a constant, but instead a function of the 2D coupling effects. The impact ionization coefficient of silicon that considers the 2D depletion effects in real-world devices is proposed and extracted in this paper. The extracted impact ionization coefficient indicates that the conventional empirical impact ionization in the Fulop equation is not suitable for the analysis of 2D lateral power devices. The veracity of the proposed impact ionization coefficient is validated by the simulations obtained from TCAD tools. Considering the complexity of direct modeling, a new prediction method using deep neural networks is proposed. The prediction method demonstrates 97.67% accuracy for breakdown location prediction and less than 6% average error for the impact ionization coefficient prediction compared with the TCAD simulation.

8.
Transl Stroke Res ; 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095840

RESUMO

Hemorrhagic foci surrounding the lacune in the long-term evolution of recent single subcortical infarcts (RSSIs) remains largely unexplored. We aimed to determine the prevalence, characteristics, and predictors of hemorrhagic foci in patients with RSSI. From a prospective, longitudinal study of RSSIs, we recruited patients who underwent multimodal MRI assessments both at baseline and approximately one year after the stroke onset. Hemorrhagic foci were identified using susceptibility-weighted imaging (SWI). Among 101 patients with RSSI, nearly half (n = 45, 44.6%) had hemorrhagic foci within the index RSSI lesions on follow-up SWI. RSSIs with hemorrhagic foci formation were associated with a longer time to follow-up imaging (median 449 versus 401 days, P = 0.005) and higher likelihood of being located in the anterior circulation compared to those without hemorrhagic foci (88.9% versus 64.3%, P = 0.003). Hemorrhagic foci were also associated with larger lesion size (P < 0.001), a higher proportion of cavitation formation (P = 0.003), higher baseline NIHSS scores (P = 0.004), and poorer functional outcomes (P = 0.001). In the subset of RSSIs in the lenticulostriate artery (LSA) territory, after adjustment for covariates, larger initial lesion volume (OR 1.80, 95% CI 1.13-2.87; P = 0.014) and greater decreases in LSA total length (OR 0.59, 95% CI 0.36-0.96; P = 0.035) were independently associated with hemorrhagic foci formation. The extent of ischemia in the initial infarct is predictive of the presence of hemorrhagic residues. Our findings contribute to the current understanding of the mechanisms underlying the evolution of RSSIs.

9.
Psychopharmacology (Berl) ; 239(1): 267-276, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34661719

RESUMO

RATIONALE: Deregulated attack behaviors have devastating social consequences; however, satisfactory clinical management for the behavior is still an unmet need so far. Social isolation (SI) has been common during the COVID-19 pandemic and may have detrimental effects on mental health, including eliciting heightened attack behavior. OBJECTIVES: This study aims to explore whether injection of ZL006 can alleviate SI-induced escalation of attack behavior in mice. METHODS: Pharmacological tools, biochemical methods, and behavioral tests were used to explore the potential therapeutic effects of ZL006 targeting postsynaptic density 95 (PSD95)/neuronal nitric oxide synthase (nNOS) pathway on escalation of attack behavior induced by SI in mice. RESULTS: ZL006 mitigated SI-induced escalated attack behaviors and elevated nitric oxide (NO) level in the cortex of the SI mice. The beneficial effects of ZL006 lasted for at least 72 h after a single injection of ZL006. Potentiation of NO levels by L-arginine blocked the effects of ZL006. Moreover, a sub-effective dose of 7-NI in combination with a sub-effective dose of ZL006 decreased both SI-induced escalated attack behaviors and NO levels in mice subjected to SI. CONCLUSIONS: Our study highlights the importance of the PSD95/nNOS pathway in mediating SI-induced escalation of attack behavior. ZL006 may be a promising therapeutic strategy for treating aggressive behaviors.


Assuntos
Agressão , Ácidos Aminossalicílicos/farmacologia , Benzilaminas/farmacologia , Proteína 4 Homóloga a Disks-Large/antagonistas & inibidores , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Isolamento Social , Animais , Camundongos
10.
ACS Appl Bio Mater ; 5(8): 3788-3794, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35916910

RESUMO

DNA tiles form through self-assembly of a small number of DNA strands that interact through basic repeated interactions, allowing the growth of nanoscale structures seeded by molecular inputs. If an approach for catalytic signal amplification can be integrated into the resultant nanostructure, then one can anticipate biosensing or diagnostic applications mediated by DNA tile self-assembly. Here, two-dimensional DNA tiles with split quadruplexes were designed as diagnostic tools for nucleic acid sensing without the use of protein enzymes. The presence of a target sequence leads to formation of extended microscale structures with arrayed multiple G-quadruplexes across the tile plane, with catalytic activity coupled to a colorimetric reporter. Such a mechanism has potential for low-cost signal amplification using unmodified DNA without the use of protein enzymes for biosensing.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Quadruplex G , Técnicas Biossensoriais/métodos , Colorimetria/métodos , DNA/química , DNA Catalítico/química
11.
Ther Adv Neurol Disord ; 15: 17562864221109746, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35813607

RESUMO

Background Purpose: Whether altered cerebral perfusion is associated with the pathogenesis of single subcortical infarctions (SSIs) in the lenticulostriate artery (LSA) territory remains unclear. Objective: We aimed to assess whether cerebral perfusion abnormalities are related to LSA impairments in the subacute phase of SSIs and then to examine their correlations with etiological subtypes of SSIs. Methods: A total of 110 patients with acute SSIs in the LSA territory were prospectively recruited between July 2017 and October 2021, and they underwent magnetic resonance perfusion-weighted imaging (PWI) and whole-brain vessel-wall imaging (VWI) within 7 days of stroke onset. Based on VWI, patients were assigned to one of two SSI subtypes: branch atheromatous disease (BAD, n = 78, 70.9%) or lacunar infarction related to cerebral small vessel disease (CSVD-related LI, n = 32, 29.1%). Perfusion maps and LSA morphology were also quantitatively assessed. Results: Based on PWI, 22 patients (20%) had hypoperfusion and 88 (80%) showed normal perfusion. Compared with normal individuals, patients with hypoperfusion showed shorter average LSA length (23.48 ± 4.81 mm versus 25.47 ± 3.74 mm, p = 0.037). Compared with patients with CSVD-related LI, patients with BAD had significantly lower relative cerebral blood flow [0.95 (IQR 0.81-1.12) versus 1.04 (IQR 0.92-1.22); p = 0.036] and cerebral blood volume [0.95 (IQR 0.84-1.15) versus 1.14 (IQR 0.97-1.27); p = 0.020] after adjusting for hypertension, number of LSA branches, and infarct volume. Conclusion: Compromised cerebral perfusion is associated with impairments in the LSA and with BAD pathogenesis. Perfusion magnetic resonance imaging can provide important insights into acute SSI pathophysiology, and it may be useful for determining the clinical significance of perfusion abnormalities in BAD occurrence.

12.
Med Phys ; 38(12): 6775-86, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22149859

RESUMO

PURPOSE: List-mode processing is an efficient way of dealing with the sparse nature of positron emission tomography (PET) data sets and is the processing method of choice for time-of-flight (ToF) PET image reconstruction. However, the massive amount of computation involved in forward projection and backprojection limits the application of list-mode reconstruction in practice, and makes it challenging to incorporate accurate system modeling. METHODS: The authors present a novel formulation for computing line projection operations on graphics processing units (GPUs) using the compute unified device architecture (CUDA) framework, and apply the formulation to list-mode ordered-subsets expectation maximization (OSEM) image reconstruction. Our method overcomes well-known GPU challenges such as divergence of compute threads, limited bandwidth of global memory, and limited size of shared memory, while exploiting GPU capabilities such as fast access to shared memory and efficient linear interpolation of texture memory. Execution time comparison and image quality analysis of the GPU-CUDA method and the central processing unit (CPU) method are performed on several data sets acquired on a preclinical scanner and a clinical ToF scanner. RESULTS: When applied to line projection operations for non-ToF list-mode PET, this new GPU-CUDA method is >200 times faster than a single-threaded reference CPU implementation. For ToF reconstruction, we exploit a ToF-specific optimization to improve the efficiency of our parallel processing method, resulting in GPU reconstruction >300 times faster than the CPU counterpart. For a typical whole-body scan with 75 × 75 × 26 image matrix, 40.7 million LORs, 33 subsets, and 3 iterations, the overall processing time is 7.7 s for GPU and 42 min for a single-threaded CPU. Image quality and accuracy are preserved for multiple imaging configurations and reconstruction parameters, with normalized root mean squared (RMS) deviation less than 1% between CPU and GPU-generated images for all cases. CONCLUSIONS: A list-mode ToF OSEM library was developed on the GPU-CUDA platform. Our studies show that the GPU reformulation is considerably faster than a single-threaded reference CPU method especially for ToF processing, while producing virtually identical images. This new method can be easily adapted to enable more advanced algorithms for high resolution PET reconstruction based on additional information such as depth of interaction (DoI), photon energy, and point spread functions (PSFs).


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Tomografia por Emissão de Pósitrons/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Biomech Model Mechanobiol ; 20(1): 243-254, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32809129

RESUMO

The adhesion of a circulating tumor cell (CTC) in a three-dimensional curved microvessel was numerically investigated. Simulations were first performed to characterize the differences in the dynamics and adhesion of a CTC in the straight and curved vessels. After that, a parametric study was performed to investigate the effects of the applied driven force density f (or the flow Reynolds number Re) and the CTC membrane bending modulus Kb on the CTC adhesion. Our simulation results show that the CTC prefers to adhere to the curved vessel as more bonds are formed around the transition region of the curved part due to the increased cell-wall contact by the centrifugal force. The parametric study also indicates that when the flow driven force f (or Re) increases or when the CTC becomes softer (Kb decreases), the bond formation probability increases and the bonds will be formed at more sites of a curved vessel. The increased f (or Re) brings a larger centrifugal force, while the decreased Kb generates more contact areas at the cell-wall interface, both of which are beneficial to the bond formation. In the curved vessel, it is found that the site where bonds are formed the most (hotspot) varies with the applied f and the Kb. For our vessel geometry, when f is small, the hotspot tends to be within the first bend of the vessel, while as f increases or Kb decreases, the hotspot may shift to the second bend of the vessel.


Assuntos
Microvasos/patologia , Células Neoplásicas Circulantes/patologia , Análise Numérica Assistida por Computador , Adesão Celular , Simulação por Computador , Humanos , Membranas , Probabilidade , Fatores de Tempo
14.
Water Res ; 196: 117039, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33761397

RESUMO

Ozone (O3) has been widely used for the elimination of recalcitrant micropollutants in aqueous environments, due to its strong oxidation ability. However, the utilization efficiency of O3 is constrained by its low solubility and short half-life during the treatment process. Herein, an integrated approach, using nanobubble technology and micro-environmental chemistry within cyclodextrin inclusion cavities, was studied in order to enhance the reactivity of ozonisation. Compared with traditional macrobubble aeration with O3 in water, nanobubble aeration achieved 1.7 times higher solubility of O3, and increased the mass transfer coefficient 4.7 times. Moreover, the addition of hydroxypropyl-ß-cyclodextrin (HPßCD) further increased the stability of O3 through formation of an inclusion complex in its molecule-specific cavity. At a HPßCD:O3 molar ratio of 10:1, the lifespan of O3 reached 18 times longer than in a HPßCD-free O3 solution. Such approach accelerated the removal efficiency of the model micropollutant, 4-chlorophenol by 6.9 times, compared with conventional macrobubble ozonation. Examination of the HPßCD inclusion complex by UV-visible spectroscopy and Nuclear Magnetic Resonance analyses revealed that both O3 and 4-chlorophenol entered the HPßCD cavity, and Benesi-Hildebrand plots indicated a 1:1 stoichiometry of the host and guest compounds. Additionally, molecular docking simulations were conducted in order to confirm the formation of a ternary complex of HPßCD:4-chlorophenol:O3 and to determine the optimal inclusion mode. With these results, our study highlights the viability of the proposed integrated approach to enhance the ozonation of organic micropollutants.


Assuntos
Ciclodextrinas , Ozônio , Poluentes Químicos da Água , 2-Hidroxipropil-beta-Ciclodextrina , Simulação de Acoplamento Molecular , Solubilidade , Poluentes Químicos da Água/análise
15.
Water Res ; 203: 117531, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388494

RESUMO

Microbial contamination of water in the form of highly-resistant bacterial spores can cause a long-term risk of waterborne disease. Advanced photocatalysis has become an effective approach to inactivate bacterial spores due to its potential for efficient solar energy conversion alongside reduced formation of disinfection by-products. However, the overall efficiency of the process still requires significant improvements. Here, we proposed and evaluated a novel visible light photocatalytic water disinfection technology by its close coupling with micro/nano bubbles (MNBs). The inactivation rate constant of Bacillus subtilis spores reached 1.28 h-1, which was 5.6 times higher than that observed for treatment without MNBs. The superior performance for the progressive destruction of spores' cells during the treatment was confirmed by transmission electron microscopy (TEM) and excitation-emission matrix (EEM) spectra determination. Experiments using scavengers of reactive oxygen species (ROSs) revealed that H2O2 and •OH were the primary active species responsible for the inactivation of spores. The effective supply of oxygen from air MNBs helped accelerate the hole oxidation of H2O2 on the photocatalyst (i.e. Ag/TiO2). In addition, the interfacial photoelectric effect from the MNBs was also confirmed to contribute to the spore inactivation. Specifically, MNBs induced strong light scattering, consequently increasing the optical path length in the photocatalysis medium by 54.8% at 700nm and enhancing light adsorption of the photocatalyst. The non-uniformities in dielectricity led to a high-degree of heterogeneity of the electric field, which triggered the formation of a region of enhanced light intensity which ultimately promoted the photocatalytic reaction. Overall, this study provided new insights on the mechanisms of photocatalysis coupled with MNB technology for advanced water treatment.


Assuntos
Desinfecção , Água , Catálise , Escherichia coli , Peróxido de Hidrogênio , Luz , Processos Fotoquímicos , Titânio
16.
Radiology ; 256(1): 243-52, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20505065

RESUMO

PURPOSE: To develop a system to facilitate the retrieval of radiologic images that contain similar-appearing lesions and to perform a preliminary evaluation of this system with a database of computed tomographic (CT) images of the liver and an external standard of image similarity. MATERIALS AND METHODS: Institutional review board approval was obtained for retrospective analysis of deidentified patient images. Thereafter, 30 portal venous phase CT images of the liver exhibiting one of three types of liver lesions (13 cysts, seven hemangiomas, 10 metastases) were selected. A radiologist used a controlled lexicon and a tool developed for complete and standardized description of lesions to identify and annotate each lesion with semantic features. In addition, this software automatically computed image features on the basis of image texture and boundary sharpness. Semantic and computer-generated features were weighted and combined into a feature vector representing each image. An independent reference standard was created for pairwise image similarity. This was used in a leave-one-out cross-validation to train weights that optimized the rankings of images in the database in terms of similarity to query images. Performance was evaluated by using precision-recall curves and normalized discounted cumulative gain (NDCG), a common measure for the usefulness of information retrieval. RESULTS: When used individually, groups of semantic, texture, and boundary features resulted in various levels of performance in retrieving relevant lesions. However, combining all features produced the best overall results. Mean precision was greater than 90% at all values of recall, and mean, best, and worst case retrieval accuracy was greater than 95%, 100%, and greater than 78%, respectively, with NDCG. CONCLUSION: Preliminary assessment of this approach shows excellent retrieval results for three types of liver lesions visible on portal venous CT images, warranting continued development and validation in a larger and more comprehensive database.


Assuntos
Hepatopatias/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X , Automação , Cistos/diagnóstico por imagem , Hemangioma/diagnóstico por imagem , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Veia Porta/diagnóstico por imagem , Padrões de Referência , Estudos Retrospectivos , Software , Terminologia como Assunto
17.
Chin J Traumatol ; 13(3): 178-81, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20515597

RESUMO

OBJECTIVE: To explore the clinical manifestation, diagnosis and surgical treatment of cerebrospinal fluid rhinorrhea in sphenoidal sinus. METHODS: Nine cases of cerebrospinal fluid rhinorrhea in sphenoidal sinus from 2007 to 2009 were retrospectively analyzed consisting of their possible etiological factors, clinical manifestations, localization of the leakage site and treatment methods. Among them, there were 3 cases of traumatic rhinorrhea, 4 postoperative rhinorrhea and 2 spontaneous rhinorrhea. All 9 patients underwent 3-dimensional CT scan in sellar region including all para-nasal sinus. Leakage site was identified and repairing procedure was performed through trans-sphenoidal approach. RESULTS: All cases were cured with the trans-sphenoidal microsurgical procedure. They were followed up for 9 months to 2 years. No recurrence, no infection and epilepsy complications were observed. CONCLUSION: For the cerebrospinal fluid rhinorrhea at sphenoidal sinus, it is critical to identify the leakage site accurately and the trans-sphenoidal approach is a microinvasive and effective way to repair the leakage, which is worthy to be advocated.


Assuntos
Rinorreia de Líquido Cefalorraquidiano/cirurgia , Microcirurgia/métodos , Seio Esfenoidal/cirurgia , Adulto , Rinorreia de Líquido Cefalorraquidiano/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
18.
Biomech Model Mechanobiol ; 19(1): 21-35, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31256275

RESUMO

An explicit immersed boundary-lattice Boltzmann method is applied to numerically investigate the dynamics of primary cilium in pulsatile blood flows with two-way fluid-structure interaction considered. To well characterize the effect of cilium basal body on cilium dynamics, the cilium base is modeled as a nonlinear rotational spring attached to the cilium's basal end as proposed by Resnick (Biophys J 109:18-25, 2015. https://doi.org/10.1016/j.bpj.2015.05.031). After several careful validations, the fluid-cilium interaction system is investigated in detail at various pulsatile flow conditions that are characterized by peak Reynolds numbers ([Formula: see text]) and Womersley numbers ([Formula: see text]). The periodic flapping of primary cilium observed in our simulations is very similar to the in vivo ciliary oscillation captured by O'Connor et al. (Cilia 2:8, 2013. https://doi.org/10.1186/2046-2530-2-8). The cilium's dynamics is found to be closely related to the [Formula: see text] and [Formula: see text]. Increase the [Formula: see text] or decrease the [Formula: see text] bring to an increase in the cilium's flapping amplitude, tip angular speed, basal rotation, and maximum tensile stress. It is also demonstrated that by reducing the [Formula: see text] or enhancing the [Formula: see text] to a certain level, one can shift the flapping pattern of cilium from its original two-side one to a one-side one, making the stretch only happen on one particular side. During the flapping process, the location of the maximum tensile stress is not always found at the basal region; instead, it is able to propagate from time to time within a certain distance to the base. Due to the obstruction of the primary cilium, the distribution of wall shear stress no longer remains uniform as in the absence of cilia. It oscillates in space with the minimum magnitude which is always found near where the cilium is located. The presence of cilium also reduces the overall level of wall shear stress, especially at the region near the cilium's anchor point.


Assuntos
Cílios/fisiologia , Modelos Biológicos , Análise Numérica Assistida por Computador , Fluxo Pulsátil/fisiologia , Simulação por Computador , Células Endoteliais/fisiologia , Gravitação , Pressão , Estresse Mecânico , Fatores de Tempo
19.
ACS Appl Mater Interfaces ; 12(30): 34130-34136, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32627523

RESUMO

MicroRNAs (miRNAs) have received extensive attention because of their potential as biomarkers for cancer diagnosis and monitoring, and their effective detection is very significant. Here, a specific, one-pot, rapid, femtomolar sensitive miRNAs detection biosensor was developed based on the target-triggered three-way junction (3-WJ) and terminal deoxynucleotide transferase (TDT)/Nt.BspQI in combination with activated copper nanoparticles (CuNPs) self-assembly. To this end, a 3-WJ hairpin probe and helper probe were designed to selectively identify the target miRNA, so as to form a stable 3-WJ structure that further triggered the double-enzyme cycling to produce poly T to activate the self-assembly of CuNPs. Based on the simplicity of CuNPs generation, the poly T template fluorescence CuNPs can detect the minimum detection limit of 1 fm within 1.75 h. In addition, the applicability of this method in complex samples was demonstrated by analyzing the whole-blood RNA extraction from Parkinson patients, consisting of the results of commercial miRNA kits. The developed strategy performs powerful implications for miRNA detection, which may be beneficial for the effective diagnostic assays and biological research of Parkinson's disease.


Assuntos
Técnicas Biossensoriais/métodos , Cobre/química , DNA Nucleotidilexotransferase/metabolismo , Nanopartículas Metálicas/química , MicroRNAs/análise , Biomarcadores/sangue , DNA Nucleotidilexotransferase/química , Sondas de DNA/metabolismo , Enzimas de Restrição do DNA/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Humanos , Limite de Detecção , MicroRNAs/sangue , Doença de Parkinson/diagnóstico , Doença de Parkinson/genética , Poli T/química , Espectrometria de Fluorescência
20.
ACS Sens ; 5(7): 1912-1920, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32575979

RESUMO

Sensitive and portable quantification of biomarkers has particular significance in the monitoring and treatment of clinical diseases. Conventional immunoassays were accustomed to introducing or incorporating enzymes for signal amplification, which commonly suffered from poor stability and inferior tolerance. Herein, we constructed a novel nonenzyme amplification methodology based on fluorogenic Ag+-tetrazolate aggregation coupled with silver corrosion sensitization for biomarker determination. A significant cascade enhancement strategy was achieved by the valid aggregation luminescence caused by the potent disintegration of silver nanoparticles. Furthermore, efficient magnetic separation was also combined and performed for the rapidity and simplicity of operation. As the target, the detection limit of prostate-specific antigen was 15.66 pg/mL in our designed biosensor. Besides, a good linear relationship was obtained. The designed biosensor demonstrated good specificity and was successfully applied to clinical serum sample detection.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Humanos , Imunoensaio , Luminescência , Masculino , Prata
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