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1.
Phys Rev Lett ; 132(3): 038302, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38307047

RESUMO

We characterize the full spatiotemporal gait of populations of swimming Escherichia coli using renewal processes to analyze the measurements of intermediate scattering functions. This allows us to demonstrate quantitatively how the persistence length of an engineered strain can be controlled by a chemical inducer and to report a controlled transition from perpetual tumbling to smooth swimming. For wild-type E. coli, we measure simultaneously the microscopic motility parameters and the large-scale effective diffusivity, hence quantitatively bridging for the first time small-scale directed swimming and macroscopic diffusion.


Assuntos
Quimiotaxia , Escherichia coli , Natação , Difusão , Marcha
2.
Neurosurg Rev ; 47(1): 70, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38277044

RESUMO

Severe postoperative pneumonia can increase the risk of poor outcomes in patients with aneurysmal subarachnoid hemorrhage (aSAH). We aimed to explore the associations of preoperative or postoperative inflammatory markers calculated from blood cell counts with severe pneumonia. This retrospective study was conducted at the First Affiliated Hospital of Yangtze University from January 2019 to June 2023. The associations of neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), platelet-lymphocyte ratio (PLR), systemic immune inflammation index (SII), and systemic inflammation response index (SIRI) with severe pneumonia were analyzed. There were 159 patients with pneumonia and 21 patients without pneumonia. There were 41 patients with severe pneumonia and 118 patients with non-severe pneumonia. The multivariate logistic regression analysis showed that NLR on the first postoperative (OR = 2.574, 95%CI: 1.035-6.403, p = 0.042) and third postoperative days (OR = 4.296, 95%CI: 1.699-10.860, p = 0.002) were associated with severe pneumonia in aSAH patients. Among patients ≥ 60 years, SIRI on the preoperative day (OR = 7.430, 95%CI: 1.443-38.251, p = 0.016) and NLR on the third postoperative day (OR = 4.748, 95%CI: 1.286-17.801, p = 0.020) were associated with severe pneumonia. Among patients < 60 years, NLR on the first postoperative day (OR = 24.149, 95%CI: 3.476-167.747, p = 0.001) was associated with severe pneumonia. The NLR on the first and third postoperative days were possibly associated with severe pneumonia in aneurysmal subarachnoid hemorrhage patients undergoing clipping or embolization surgeries. Dynamic detection of NLR during early perioperative period may help clinicians to predict the development of severe pneumonia.


Assuntos
Pneumonia , Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/cirurgia , Estudos Retrospectivos , Neutrófilos , Pneumonia/etiologia , Pneumonia/complicações , Linfócitos , Inflamação/complicações
3.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34588304

RESUMO

Virtually all of the many active matter systems studied so far are made of units (biofilaments, cells, colloidal particles, robots, animals, etc.) that move even when they are alone or isolated. Their collective properties continue to fascinate, and we now understand better how they are unique to the bulk transduction of energy into work. Here we demonstrate that systems in which isolated but potentially active particles do not move can exhibit specific and remarkable collective properties. Combining experiments, theory, and numerical simulations, we show that such subcritical active matter can be realized with Quincke rollers, that is, dielectric colloidal particles immersed in a conducting fluid subjected to a vertical DC electric field. Working below the threshold field value marking the onset of motion for a single colloid, we find fast activity waves, reminiscent of excitable systems, and stable, arbitrarily large self-standing vortices made of thousands of particles moving at the same speed. Our theoretical model accounts for these phenomena and shows how they can arise in the absence of confining boundaries and individual chirality. We argue that our findings imply that a faithful description of the collective properties of Quincke rollers need to consider the fluid surrounding particles.

4.
Ultraschall Med ; 45(2): 168-175, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37402406

RESUMO

PURPOSE: To collect validity evidence for a simulator-based obstetric ultrasound competency assessment tool (OUCAT). METHODS: 89 sonographers from three centers (XY, MC, DT), including novices (n=21), experienced trainees (n=44), and experts (n=24), participated in the competency assessment. Validity evidence of OUCAT was collected according to Standards for Educational and Psychological Testing. Content validity was ensured by reviewing guidelines and reaching expert consensus. The response process was ensured via training raters. Internal structure was explored through internal consistency, inter-rater reliability, and test-retest reliability. Relations to other variables were explored by comparing OUCAT scores of sonographers with different experience. Evidence for consequences was collected by determining the pass/fail level. RESULTS: OUCAT included 123 items, of which 117 items could effectively distinguish novices from experts (P<0.05). The internal consistency was represented by the Cronbach's α coefficient (0.978). The inter-rater reliability was high, with XY being 0.868, MC being 0.877, and DT being 0.937 (P<0.001). Test-retest reliability was 0.732 (P=0.001). The performance of experts was significantly better than experienced trainees, and the performance of experienced trainees was significantly better than novices (70.3±10.7 vs. 39.8±15.0 vs. 20.5±10.6, P<0.001). The pass/fail level determined by contrast group method was 45 points. The passing rate of novices, experienced trainees and experts was 0% (0/21), 31.8% (14/44), and 100% (24/24), respectively. CONCLUSION: Simulator-based OUCAT exhibits good reliability and validity in assessing obstetric ultrasound skills.


Assuntos
Competência Clínica , Ultrassonografia Pré-Natal , Feminino , Gravidez , Humanos , Reprodutibilidade dos Testes , Ultrassonografia , Avaliação Educacional/métodos
5.
Langmuir ; 39(31): 10806-10819, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37501336

RESUMO

Due to its abundance in blood, a great deal of research has been undertaken to develop efficient biosensors for serum albumin and provide insight into the interactions that take place between these biosensing molecules and the protein. Near-infrared (NIR, >700 nm) organic dyes have been shown to be effective biosensors of serum albumin, but their effectiveness is diminished in whole blood. Herein, it is shown that an NIR sulfonate indolizine-donor-based squaraine dye, SO3SQ, can be strengthened as a biosensor of albumin through the addition of biocompatible ionic liquids (ILs). Specifically, the IL choline glycolate (1:1), at a concentration of 160 mM, results in the enhanced fluorescence emission ("switch-on") of the dye in the presence of blood. The origin of the fluorescence enhancement was investigated via methods, including DLS, ITC, and molecular dynamics. Further, fluorescence measurements were conducted to see the impact the dye-IL system had on the fluorescence of the tryptophan residue of human serum albumin (HSA), as well as to determine its apparent association constants in relation to albumin. Circular dichroism (CD) spectroscopy was used to provide evidence that the dye-IL system does not alter the secondary structures of albumin or DNA. Our results suggest that the enhanced fluorescence of the dye in the presence of IL and blood is due to diversification of binding sites in albumin, controlled by the interaction of the IL-dye-albumin complex.


Assuntos
Líquidos Iônicos , Humanos , Líquidos Iônicos/química , Albumina Sérica/química , Albumina Sérica Humana/química , Sítios de Ligação , Triptofano/química , Espectrometria de Fluorescência/métodos , Dicroísmo Circular
6.
Fish Shellfish Immunol ; 131: 1173-1181, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36371051

RESUMO

The use of Clostridium butyricum in crustacean aquaculture for anti-abiotic stress is yet unknown. Feeds were formulated containing 0, 125, 250, 500, and 1000 mg/kg Clostridium butyricum (2 × 107 CFU/g), respectively. The giant freshwater prawns (Macrobrachium rosenbergii) were fed for 8 weeks in triplicate. The results showed that C. butyricum-supplemented groups improved growth performance significantly with the optimum level at 610 mg/kg. Ammonia stress reduced hemolymph glucose, total protein, total cholesterol, and triglyceride concentrations while dietary C. butyricum significantly increased hemolymph glucose and total protein levels after the ammonia challenge. Ammonia stress increased inducible nitric oxide synthase (iNOS) and nitric oxide (NO) levels, and the treatments supplemented with C. butyricum had considerably enhanced levels of iNOS and NO after stress. Treatment with C. butyricum increased the level of superoxide dismutase (SOD), and decreased the level of malondialdehyde (MDA) and superoxide anion, with the 125 mg/kg treated groups having the extreme value. Furthermore, C. butyricum-treated groups reduced the expression of HSPs after ammonia stress while the ammonia stress induced the expression of HSP60, HSP70, and HSP90. Dietary C. butyricum elevated the expression of peroxiredoxin-5 and toll in response to ammonia stress. The results indicate that dietary supplementation with 125-500 mg/kg of C. butyricum (2 × 107 CFU/g) improved biochemical and antioxidant features as well as intestinal immunity of M. rosenbergii under ammonia challenge by activating the toll signal pathway.


Assuntos
Clostridium butyricum , Palaemonidae , Animais , Clostridium butyricum/fisiologia , Amônia/farmacologia , Estresse Oxidativo , Água Doce , Glucose
7.
Int J Hyperthermia ; 39(1): 557-563, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35379066

RESUMO

AIM: This study aimed to develop a novel tumor-bearing tissue phantom model that can be used for US/CT/MR-guided tumor puncture and thermal ablation. METHODS: The phantom model comprised two parts: a normal tissue-mimicking phantom and a tumor-mimicking phantom. A normal tissue phantom was prepared based on a polyacrylamide gel mixed with thermochromic ink. Moreover, a spherical phantom containing contrast agents was constructed and embedded in the tissue phantom to mimic a tumor lesion. US/CT/MR imaging features and thermochromic property of the phantom model were characterized. Finally, the utility of the phantom model for imaging-guided microwave ablation training was examined. RESULTS: The tumor phantom containing contrast agents showed hyper-echogenicity, higher CT numbers, and lower T2 signal intensity compared with the normal tissue phantom in US/CT/MR images. Consequently, we could locate the position of the tumor in US/CT/MR imaging and perform an imaging-guided tumor puncture. When the temperature reached the threshold of 60 °C, the phantom exhibited a permanent color change from cream white to magenta. Based on this obvious color change, our phantom model could clearly map the thermal ablation region after thermotherapy. CONCLUSIONS: We developed a novel US/CT/MR-imageable tumor-bearing tissue model that can be used for imaging-guided tumor puncture and thermal ablation. Furthermore, it allows visual assessment of the ablation region by analyzing the obvious color change. Overall, this phantom model could be a good training tool in the field of thermal ablation.


Assuntos
Hipertermia Induzida , Neoplasias , Humanos , Imageamento por Ressonância Magnética/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/cirurgia , Punções , Tomografia Computadorizada por Raios X/métodos
8.
Biochem Biophys Res Commun ; 534: 468-473, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33256978

RESUMO

The postponement of childbearing by women has led to an increase in infertility. The reproductive aging process leads to a decrease in both the quantity and quality of oocytes. The aim of this study was to investigate exosomal microRNAs in human ovarian follicular fluid and explore their potential association with oocyte quality. We collected ovarian follicle fluid from 68 patients and assigned the patients to A (superior oocyte quality) or B (poor oocyte quality) group according to their oocyte quality. Exosomal miRNAs were extracted, library constructed and sequenced using the Illumina HiSeq platform. Subsequently, we analyzed exosomal miRNA expression, predicted the miRNA target genes, and enriched Gene Ontology terms using GOSeq. Kyoto Encyclopedia of Genes and Genomes pathway analysis was performed using miRanda. A total of 47 miRNAs were found to be significantly differentially expressed between group A and group B (p < 0.05). Among nine differentially expressed miRNAs that were previously known, seven were upregulated in group B. In silico analysis indicated that several of these exosomal miRNAs were involved in pathways implicated in oocyte quality. Analysis of the expression of exosomal miRNAs in human ovarian follicular fluid showed that they were critical for maintaining oocyte quality. Our findings provide the basis for further investigations of the functions of exosomal miRNAs in the ovarian microenvironment and suggest that these exosomal miRNAs may be potential biomarkers for evaluating oocyte quality. The findings are potentially important to maintain oocyte quality in clinical settings.


Assuntos
Exossomos/genética , Líquido Folicular/metabolismo , MicroRNAs/genética , Oócitos/metabolismo , Feminino , Ontologia Genética , Humanos , MicroRNAs/análise , Oócitos/citologia
9.
Phys Rev Lett ; 126(5): 058001, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33605769

RESUMO

We investigate how light polarization affects the motion of photoresponsive algae, Euglena gracilis. In a uniformly polarized field, cells swim approximately perpendicular to the polarization direction and form a nematic state with zero mean velocity. When light polarization varies spatially, cell motion is modulated by local polarization. In such light fields, cells exhibit complex spatial distribution and motion patterns which are controlled by topological properties of the underlying fields; we further show that ordered cell swimming can generate directed transporting fluid flow. Experimental results are quantitatively reproduced by an active Brownian particle model in which particle motion direction is nematically coupled to local light polarization.


Assuntos
Euglena gracilis/fisiologia , Modelos Biológicos , Luz , Movimento
10.
Langmuir ; 37(3): 1279-1287, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33434432

RESUMO

The synthesis of highly water-dispersible iron oxide nanoparticles with surface functional groups and precisely controlled sizes is essential for biomedical application. In this paper, we report a one-pot strategy for versatile surface functionalization. The iron oxide nanoparticles are first synthesized by thermal decomposition of iron(III) acetylacetonate (Fe(acac)3) in diethylene glycol (DEG), and their surfaces are modified by adding the surface ligands at the end of the reaction. The size of iron oxide nanoparticles can be precisely controlled in nanometer scale by continuous growth. This facile synthesis method enables the surface modification with different coating materials such as dopamine (DOPA), polyethylene glycol with thiol end group (thiol-PEG), and poly(acrylic acid) (PAA) onto the iron oxide nanoparticles, introducing new surface functionalities for future biomedical application. From transmission electron microscopy (TEM) and X-ray diffraction (XRD), the morphology and crystal structure are not changed during surface functionalization. The attachment of surface ligands is studied by Fourier transform infrared spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). The surface functional groups are confirmed by X-ray Photoelectron Spectroscopy (XPS). In correlation with the change of hydrodynamic size, PAA coated nanoparticles are found to exhibit outstanding stability in aqueous solution. Furthermore, we demonstrate that the functional groups are available for conjugating with other molecules such as fluorescent dye, showing potential biological applications. Lastly, the magnetic resonance phantom studies demonstrate that iron oxide nanoparticles with PAA coating can be used as T1 and T2 dual-modality contrast agents. Both r1 and r2 relaxivities significantly increase after surface functionalization with PAA, indicating improved sensitivity.

11.
J Nanobiotechnology ; 19(1): 171, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103070

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a type of head and neck malignant tumor with a high incidence in specific regional distribution, and its traditional therapies face some challenges. It has become an urgent need to seek new therapeutic strategies without or with low toxicity and side effects. At present, more and more researchers has been attracting attention by nanotheranostic platform. Therefore, our team synthesized the polyethylene glycol-coated ultrasmall superparamagnetic iron oxide nanoparticles-coupled sialyl Lewis X (USPIO-PEG-sLex) nanotheranostic platform with high temperature pyrolysis. RESULTS: The USPIO-PEG-sLex nanoparticles had excellent photothermal conversion property, and the temperature of USPIO-PEG-sLex nanoparticles solution increased with its concentration and power density of near-infrared (NIR) on 808 nm wavelengths. Five USPIO-PEG-sLex nanoparticles with different concentrations of 0 mg/ml, 0.025 mg/ml, 0.05 mg/ml, 0.1 mg/ml and 0.2 mg/ml were prepared. The biological toxicity results showed that the viability of NPC 5-8F cells is related to the concentration of USPIO-PEG-sLex nanoparticles and the culture time (P < 0.001). The results of photothermal therapy (PTT) in vitro indicated that the viability of 5-8F cells decreased significantly with the concentration of USPIO-PEG-sLex nanoparticles increases (P < 0.001), and the viability of NPC 5-8F cells were 91.04% ± 5.20%, 77.83% ± 3.01%, 73.48% ± 5.55%, 59.50% ± 10.98%, 17.11% ± 3.14%, respectively. The USPIO-PEG-sLex nanoparticles could target the tumor area, and reduce the T2* value of tumor tissue. The T2* values of tumor pre- and post-injection were 30.870 ± 5.604 and 18.335 ± 4.351, respectively (P < 0.001). In addition, USPIO-PEG-sLex nanoparticles as a photothermal agent for PTT could effectively inhibit tumor progression. The ratio of volume change between tail vein injection group, control group, nanoparticles without laser irradiation group and blank group after 5 treatments were 3.04 ± 0.57, 5.80 ± 1.06, 8.09 ± 1.96, 7.89 ± 2.20, respectively (P < 0.001). CONCLUSIONS: Our synthesized USPIO-PEG-sLex nanotheranostic platform, and it may be become a new strategy for the treatment of NPC.


Assuntos
Dextranos/química , Nanopartículas de Magnetita/química , Nanopartículas/química , Carcinoma Nasofaríngeo/tratamento farmacológico , Terapia Fototérmica/métodos , Polietilenoglicóis/química , Antígeno Sialil Lewis X/farmacologia , Nanomedicina Teranóstica/métodos , Animais , Linhagem Celular Tumoral , Nanopartículas Magnéticas de Óxido de Ferro , Imageamento por Ressonância Magnética/métodos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Carcinoma Nasofaríngeo/diagnóstico por imagem , Neoplasias Nasofaríngeas , Fototerapia , Antígeno Sialil Lewis X/química
12.
BMC Genet ; 20(1): 63, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31349781

RESUMO

BACKGROUND: The tryptophan-arginine-lysine-tyrosine (WRKY) transcription factors play important roles in plants, allowing them to adapt to environmental conditions that are not normally conducive to plant growth; in particular, drought. There has been extensive research on WRKY transcription factors and the effects of their overexpression in plants on resistance to drought stress. However, due to the materials (the type and species of donor and receptor, promoters) and treatments (the type and time of stress) used, different and often confounding results have been obtained between studies. Meta-analysis is a powerful statistical tool that can be used to summarize results from numerous independent experiments on the same research topic while accounting for variability across experiments. RESULTS: We carried out a meta-analysis of 16 measured parameters that affect drought resistance in plants overexpressing WRKY transcription factors and wild-type plants. We found that only one of these parameters was significantly different between transgenic and wild-type plants under drought and control conditions at a 95% confidence interval (p = 0.000, p = 0.009, respectively). Eleven of the sixteen parameters were obviously different in WRKY transgenic plants under drought and control conditions (SV, p = 0.023, SSC, p = 0.000, SOD, p = 0.012, SFW, p = 0.000, RL, p = 0.016, Pro, p = 0.000, POD, p = 0.027, MDA, p = 0.000, H2O2, p = 0.003, EL, p = 0.000, CHC, p = 0.000, respectively), seven of the eleven obviously different parameters showed positive effect (SSC, SOD, Pro, POD, MDA, H2O2, EL), four of them revealed negative effect (SV, SFW, RL, CHC). CONCLUSION: We have found that only one of these parameters was significantly different between transgenic and wild-type plants under drought and control conditions respectively, at a 95% confidence interval. And eleven of sixteen parameters showed obviously different of WRKY-overexpressed plants under different conditions (water-stressed and normal), suggesting that WRKY transcription factors play an important role in plant responses to drought stress. These findings also provide a theoretical basis for further study of the role of WRKY transcription factors in the regulation of plant responses to environmental stress.


Assuntos
Secas , Expressão Gênica , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Açúcares/metabolismo , Fatores de Transcrição/metabolismo
13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(6): 649-656, 2019 Jun 28.
Artigo em Zh | MEDLINE | ID: mdl-31304926

RESUMO

OBJECTIVE: To compare the clinical value of superb microvascular imaging (SMI) and contrast enhanced ultrasound (CEUS) in the differential diagnosis of thyroid nodules, and to further study whether the combination of SMI and/or CEUS with thyroid imaging reporting and data system (TI-RADS) can improve the diagnostic value of TI-RADS.
 Methods: SMI, CEUS, TI-RADS, TI-RADS combined with CEUS, TI-RADS combined with SMI, TI-RADS combined with SMI and CEUS were used to differentiate thyroid nodules. TI-RADS 4b, 5 categories in two-dimensional ultrasound, hypoenhancement in CEUS, and peripheral blood flow with penetrating vessels in SMI were considered malignant signs. The diagnostic efficacy of these methods was compared according to post-operative pathology or fine needle aspiration cytology.
 Results: A total of 237 patients with 296 thyroid nodules were included in the study. The sensitivity, specificity and accuracy for TI-RADS were 78.4%, 77.7% and 78.0% respectively, 75.5%, 86.6% and 81.4% in SMI, 82.0%, 88.5% and 85.5% in CEUS, 92.1%, 90.4% and 91.2% in TI-RADS combined with SMI and CEUS. Area under the receiver operating characteristic curve (AUROC) showed no significant difference between SMI, CEUS, TI-RADS (χ2=4.29, P=0.117). AUROC of both TI-RADS combined with CEUS (χ2=39.62, P<0.001), TI-RADS combined with SMI (χ2=36.61, P<0.001) were higher than TI-RADS. AUROC of TI-RADS combined with SMI and CEUS was higher than TI-RADS combined with SMI (χ2=4.50, P=0.033) or TI-RADS combined with CEUS (χ2=4.24, P=0.039).
 Conclusion: Peripheral blood flow with penetrating vessels in SMI possesses high diagnostic value in differentiating thyroid cancer. The combination of SMI and/or CEUS with TI-RADS can be used to improve the diagnostic efficacy of TI-RADS in differential diagnosis of thyroid nodules.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Diagnóstico Diferencial , Humanos , Ultrassonografia
14.
Mol Imaging ; 17: 1536012118775827, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29873290

RESUMO

PURPOSE: Melanoma is a lethal skin cancer with unmet clinical needs for targeted imaging and therapy. Nanoscale materials conjugated with targeting components have shown great potential to improve tumor delivery efficiency while minimizing undesirable side effects in vivo. Herein, we proposed to develop targeted nanoparticles for melanoma theranostics. METHOD: In this work, gold nanocages (AuNCs) were conjugated with α-melanocyte-stimulating hormone (α-MSH) peptide and radiolabeled with 64Cu for melanocortin 1 receptor-(MC1R) targeted positron emission tomography (PET) in a mouse B16/F10 melanoma model. RESULTS: Their controlled synthesis and surface chemistry enabled well-defined structure and radiolabeling efficiency. In vivo pharmacokinetic evaluation demonstrated comparable organ distribution between the targeted and nontargeted AuNCs. However, micro-PET/computed tomography (CT) imaging demonstrated specific and improved tumor accumulation via MC1R-mediated delivery. By increasing the coverage density of α-MSH peptide on AuNCs, the tumor delivery efficiency was improved. CONCLUSION: The controlled synthesis, sensitive PET imaging, and optimal tumor targeting suggested the potential of targeted AuNCs for melanoma theranostics.


Assuntos
Ouro/química , Melanoma Experimental/diagnóstico por imagem , Melanoma Experimental/patologia , Nanopartículas Metálicas/química , Imagem Molecular/métodos , Tomografia por Emissão de Pósitrons , Receptor Tipo 1 de Melanocortina/metabolismo , Animais , Nanopartículas Metálicas/ultraestrutura , Camundongos Endogâmicos C57BL , Polietilenoglicóis/química , Distribuição Tecidual , Tomografia Computadorizada por Raios X , alfa-MSH/química
15.
Phys Rev Lett ; 120(19): 198103, 2018 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29799236

RESUMO

We study the transport of self-propelled particles in dynamic complex environments. To obtain exact results, we introduce a model of run-and-tumble particles (RTPs) moving in discrete time on a d-dimensional cubic lattice in the presence of diffusing hard-core obstacles. We derive an explicit expression for the diffusivity of the RTP, which is exact in the limit of low density of fixed obstacles. To do so, we introduce a generalization of Kac's theorem on the mean return times of Markov processes, which we expect to be relevant for a large class of lattice gas problems. Our results show the diffusivity of RTPs to be nonmonotonic in the tumbling probability for low enough obstacle mobility. These results prove the potential for the optimization of the transport of RTPs in crowded and disordered environments with applications to motile artificial and biological systems.


Assuntos
Modelos Teóricos , Movimento (Física) , Difusão , Cadeias de Markov
16.
Ann Hematol ; 97(6): 925-944, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29500711

RESUMO

The effect of immunomodulatory drugs (IMiDs) on serious infection remains uncertain. We therefore conducted a systematic review and meta-analysis to assess the possible impact of IMiDs on serious infection in patients with multiple myeloma (MM). We searched randomized controlled trials (RCTs) and observational studies from databases that addressed the effect of IMiDs on serious infection in patients with MM. We pooled data from RCTs and observational studies separately and used the GRADE approach to rate the quality of evidence. Rates in patients with individual IMiDs at different treatment status ranged from 7.00 to 23.00%. The use of thalidomide- or lenalidomide-based regimen induction therapy for autologous stem cell transplantation (ASCT)-ineligible patients suggests increase in serious infection (RR = 1.59, 95% CI 1.31-1.93, p < 0.01). Compared to conventional therapy, IMiDs' induction in ASCT-eligible patients significantly decreases the risk of serious infection (RR = 0.82, 95% CI 0.72-0.94, p < 0.01). Lenalidomide-based therapy was associated with a significant increase in risk of serious infection in patients treated compared with conventional therapy (RR = 2.45, 95% CI 1.57-3.83, p < 0.01). The current evidence suggests that patients with MM treated with IMiDs are at a high risk of serious infection.


Assuntos
Medicina Baseada em Evidências , Hospedeiro Imunocomprometido , Fatores Imunológicos/efeitos adversos , Mieloma Múltiplo/tratamento farmacológico , Infecções Oportunistas/imunologia , Quimioterapia Combinada/efeitos adversos , Humanos , Fatores Imunológicos/uso terapêutico , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Incidência , Quimioterapia de Indução/efeitos adversos , Lenalidomida , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/microbiologia , Estudos Observacionais como Assunto , Infecções Oportunistas/complicações , Infecções Oportunistas/epidemiologia , Infecções Oportunistas/microbiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Risco , Talidomida/efeitos adversos , Talidomida/análogos & derivados , Talidomida/uso terapêutico
17.
J Ultrasound Med ; 37(2): 425-437, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28880412

RESUMO

OBJECTIVES: We aimed to determine the most efficient quantitative parameters to establish a contrast-enhanced ultrasound (US) assessment system for distinguishing between benign and malignant thyroid nodules. METHODS: A total of 167 patients with thyroid solitary nodules had the diagnosis confirmed by surgery or fine-needle aspiration. Quantitative contrast-enhanced US indicators (time to peak, time from peak to one-half, ascend slope, descend slope, peak intensity, and area under the curve [AUC]) were gathered in nodule and perinodule areas. Univariate and multivariate logistic regression analyses were performed. Receiver operating characteristic curves were generated. Sensitivities, specificities, and positive and negative predictive values were calculated to identify the best cutoff value. RESULTS: The univariate logistic regression model showed that the peak intensity, ascend slope, descend slope, and AUC were significant indicators for discriminating benign from malignant nodules under contrast-enhanced US (P < .0001). For thyroid nodules, low peak intensity, ascend slope, and AUC and high descend slope values were significant indicators of malignancy. However, in perinodule areas, high peak intensity, ascend slope, and AUC and low descend slope values were significantly associated with malignancies. The cutoff values for the nodule peak intensity, ascend slope, descend slope, and AUC were 20.75, 0.91, -0.2, and 1818.23, respectively. The cutoff values for the ratios of the nodule versus perinodule peak intensity, ascend slope, descend slope, and AUC were 0.90, 0.95, 0.96, and 0.96. The nodule-to-perinodule peak intensity ratio showed the best diagnostic efficiency, with 80.41% sensitivity and 80.00% specificity. CONCLUSIONS: Quantitative contrast-enhanced US indicators help discriminate benign from malignant thyroid nodules. The nodule-to-perinodule peak intensity ratio showed the best diagnostic efficiency.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Diagnóstico Diferencial , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Glândula Tireoide/diagnóstico por imagem
18.
Zhongguo Zhong Yao Za Zhi ; 43(22): 4450-4456, 2018 Nov.
Artigo em Zh | MEDLINE | ID: mdl-30593237

RESUMO

As one of the three pillars of Chinese medicine industry, traditional Chinese medicines prepared in ready-to-use forms are important raw materials for clinical medication and production of Chinese patent drugs. By considering the literature of Curcumae Radix, a multi-source Chinese herb and the situation of market investigation, the modern evaluation method based on traditional grading was introduced for comprehensive evaluation of the processed Curcumae Radix. The correlation between traditional grading method and modern evaluation index was explored to establish the grading standard of Curcumae Radix. According to the comprehensive evaluation, Curcumae Radix was divided into four grades: superior, first, second and third grades under the guidance of the theory of traditional Chinese medicine. This study provides a new idea for the grading of multi-source processed Chinese medicine, achieving high quality and good price, which is helpful to improve the clinical efficacy.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Raízes de Plantas
19.
Radiology ; 283(3): 758-768, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28045644

RESUMO

Purpose To characterize a chemokine receptor type 2 (CCR2)-binding peptide adapted for use as a positron emission tomography (PET) radiotracer for noninvasive detection of lung inflammation in a mouse model of lung injury and in human tissues from subjects with lung disease. Materials and Methods The study was approved by institutional animal and human studies committees. Informed consent was obtained from patients. A 7-amino acid CCR2 binding peptide (extracellular loop 1 inverso [ECL1i]) was conjugated to tetraazacyclododecane tetraacetic acid (DOTA) and labeled with copper 64 (64Cu) or fluorescent dye. Lung inflammation was induced with intratracheal administration of lipopolysaccharide (LPS) in wild-type (n = 19) and CCR2-deficient (n = 4) mice, and these mice were compared with wild-type mice given control saline (n = 5) by using PET performed after intravenous injection of 64Cu-DOTA-ECL1i. Lung immune cells and those binding fluorescently labeled ECL1i in vivo were detected with flow cytometry. Lung inflammation in tissue from subjects with nondiseased lungs donated for lung transplantation (n = 11) and those with chronic obstructive pulmonary disease (COPD) who were undergoing lung transplantation (n = 16) was evaluated for CCR2 with immunostaining and autoradiography (n = 6, COPD) with 64Cu-DOTA-ECL1i. Groups were compared with analysis of variance, the Mann-Whitney U test, or the t test. Results Signal on PET images obtained in mouse lungs after injury with LPS was significantly greater than that in the saline control group (mean = 4.43% of injected dose [ID] per gram of tissue vs 0.99% of injected dose per gram of tissue; P < .001). PET signal was significantly diminished with blocking studies using nonradiolabeled ECL1i in excess (mean = 0.63% ID per gram of tissue; P < .001) and in CCR2-deficient mice (mean = 0.39% ID per gram of tissue; P < .001). The ECL1i signal was associated with an elevated level of mouse lung monocytes. COPD lung tissue displayed significantly elevated CCR2 levels compared with nondiseased tissue (median = 12.8% vs 1.2% cells per sample; P = .002), which was detected with 64Cu-DOTA-ECL1i by using autoradiography. Conclusion 64Cu-DOTA-ECL1i is a promising tool for PET-based detection of CCR2-directed inflammation in an animal model and in human tissues as a step toward clinical translation. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Pneumonia/diagnóstico por imagem , Pneumonia/imunologia , Tomografia por Emissão de Pósitrons , Receptores CCR2/análise , Animais , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Tomografia por Emissão de Pósitrons/métodos
20.
Eur Radiol ; 27(4): 1527-1536, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27525973

RESUMO

PURPOSE: To study the thyroid image reporting and data system (TI-RADS) classification and the contrast-enhanced ultrasound (CEUS) enhancement pattern of thyroid nodules, and to determine whether combined use of both methods is helpful in the diagnosis of thyroid nodules. METHODS: A total of 319 thyroid nodules in 246 patients were assessed with TI-RADS, CEUS and a combination of both methods. The diagnostic performance of TI-RADS, CEUS and a combination of both methods was compared. RESULTS: The accuracy in the diagnosis of thyroid nodules was 90.3 % for TI-RADS, 90.0 % for CEUS and 96.0 % for a combination of both methods respectively. A statistically significant difference was not observed in the diagnostic accuracy of CEUS and TI-RADS (P > 0.05). However, a significant difference was observed between a combination of both methods and either alone (P < 0.01). A combination of both methods showed high sensitivity, specificity and accuracy for TI-RADS classifications of 4a and 4b thyroid nodules compared with TI-RADS alone (P < 0.01) and a statistically significant difference was not observed for thyroid nodules classified as 2, 3, and 5 (P > 0.05). CONCLUSIONS: The improved TI-RADS, when combined with CEUS, could significantly improve the diagnostic accuracy for thyroid nodules, especially for TI-RADS class-4 thyroid nodules. KEY POINTS: • TI-RADS can be used as the primary diagnostic standard for thyroid nodules • CEUS can be used as an important complement to TI-RADS • The improved TI-RADS can significantly improve the qualitative diagnostic accuracy.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Sistemas de Informação em Radiologia , Nódulo da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Adulto Jovem
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