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1.
Environ Res ; 238(Pt 1): 117163, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37722583

RESUMO

The current study has focused on electrochemical immunosensing of carcinoembryonic antigen (CEA) employing an immobilized antibody on a thionine, chitosan, or graphene oxide nanocomposite modified glassy carbon electrode (anti-CEA/THi-CS-GO/GCE) as an indicator of cancer monitoring. THi-CS-GO nanocomposites were made using ultrasonication, and analyses of their morphology and crystal structure using SEM, FTIR, and XRD showed that thionine and chitosan molecules were intercalated with stacking interactions with both the top and bottom of GO nanosheets. Electrochemical experiments revealed anti-CEA, THi-CS-GO/GCE to have exceptional sensitivity and selectivity towards CEA compounds. The detection limit value was established to be 0.8 pg/mL when it was discovered that variations in the decrease peak current were directly proportional to the logarithm concentration of CEA over a wide range from 10-3 to 104 ng/mL. Results of testing the immunosensor's application capability for detecting CEA in a sample of human serum show that ELISA and DPV results are very congruent. The produced immunosensor demonstrated adequate immunosensor precision in determining CEA in prepared genuine samples of human serum and clinical applications.


Assuntos
Técnicas Biossensoriais , Quitosana , Nanopartículas Metálicas , Nanocompostos , Neoplasias , Humanos , Quitosana/química , Antígeno Carcinoembrionário/análise , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Ouro/química , Técnicas Eletroquímicas/métodos , Nanocompostos/química , Limite de Detecção , Nanopartículas Metálicas/química
2.
Micromachines (Basel) ; 12(12)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34945321

RESUMO

Mixing at the microscale is of great importance for various applications ranging from biological and chemical synthesis to drug delivery. Among the numerous types of micromixers that have been developed, planar passive spiral micromixers have gained considerable interest due to their ease of fabrication and integration into complex miniaturized systems. However, less attention has been paid to non-planar spiral micromixers with various cross-sections and the effects of these cross-sections on the total performance of the micromixer. Here, mixing performance in a spiral micromixer with different channel cross-sections is evaluated experimentally and numerically in the Re range of 0.001 to 50. The accuracy of the 3D-finite element model was first verified at different flow rates by tracking the mixing index across the loops, which were directly proportional to the spiral radius and were hence also proportional to the Dean flow. It is shown that higher flow rates induce stronger vortices compared to lower flow rates; thus, fewer loops are required for efficient mixing. The numerical study revealed that a large-angle outward trapezoidal cross-section provides the highest mixing performance, reaching efficiencies of up to 95%. Moreover, the velocity/vorticity along the channel length was analyzed and discussed to evaluate channel mixing performance. A relatively low pressure drop (<130 kPa) makes these passive spiral micromixers ideal candidates for various lab-on-chip applications.

3.
Sci Rep ; 10(1): 5929, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32246111

RESUMO

Inertial microfluidics has been broadly investigated, resulting in the development of various applications, mainly for particle or cell separation. Lateral migrations of these particles within a microchannel strictly depend on the channel design and its cross-section. Nonetheless, the fabrication of these microchannels is a continuous challenging issue for the microfluidic community, where the most studied channel cross-sections are limited to only rectangular and more recently trapezoidal microchannels. As a result, a huge amount of potential remains intact for other geometries with cross-sections difficult to fabricate with standard microfabrication techniques. In this study, by leveraging on benefits of additive manufacturing, we have proposed a new method for the fabrication of inertial microfluidic devices. In our proposed workflow, parts are first printed via a high-resolution DLP/SLA 3D printer and then bonded to a transparent PMMA sheet using a double-coated pressure-sensitive adhesive tape. Using this method, we have fabricated and tested a plethora of existing inertial microfluidic devices, whether in a single or multiplexed manner, such as straight, spiral, serpentine, curvilinear, and contraction-expansion arrays. Our characterizations using both particles and cells revealed that the produced chips could withstand a pressure up to 150 psi with minimum interference of the tape to the total functionality of the device and viability of cells. As a showcase of the versatility of our method, we have proposed a new spiral microchannel with right-angled triangular cross-section which is technically impossible to fabricate using the standard lithography. We are of the opinion that the method proposed in this study will open the door for more complex geometries with the bespoke passive internal flow. Furthermore, the proposed fabrication workflow can be adopted at the production level, enabling large-scale manufacturing of inertial microfluidic devices.

4.
Soft Matter ; 16(10): 2448-2459, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-31984393

RESUMO

Inertial microfluidics has emerged over the past decade as a powerful tool to accurately control cells and microparticles for diverse biological and medical applications. Many approaches have been proposed to date in order to increase the efficiency and accuracy of inertial microfluidic systems. However, the effects of channel cross-section and solution properties (Newtonian or non-Newtonian) have not been fully explored, primarily due to limitations in current microfabrication methods. In this study, we overcome many of these limitations using wax 3D printing technology and soft lithography through a novel workflow, which eliminates the need for the use of silicon lithography and polydimethylsiloxane (PDMS) bonding. We have shown that by adding dummy structures to reinforce the main channels, optimizing the gap between the dummy and main structures, and dissolving the support wax on a PDMS slab to minimize the additional handling steps, one can make various non-conventional microchannels. These substantially improve upon previous wax printed microfluidic devices where the working area falls into the realm of macrofluidics rather than microfluidics. Results revealed a surface roughness of 1.75 µm for the printed channels, which does not affect the performance of inertial microfluidic devices used in this study. Channels with complex cross-sections were fabricated and then analyzed to investigate the effects of viscoelasticity and superposition on the lateral migration of the particles. Finally, as a proof of concept, microcarriers were separated from human mesenchymal stem cells using an optimized channel with maximum cell-holding capacity, demonstrating the suitability of these microchannels in the bioprocessing industry.


Assuntos
Dimetilpolisiloxanos/química , Dispositivos Lab-On-A-Chip , Microtecnologia/instrumentação , Impressão Tridimensional , Ceras/química , Linhagem Celular , Desenho de Equipamento , Humanos , Células-Tronco Mesenquimais/citologia , Técnicas Analíticas Microfluídicas/instrumentação , Microesferas
5.
J Cutan Pathol ; 45(12): 933-939, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30175468

RESUMO

A subset of soft tissue sarcomas often harbors recurrent fusions involving protein kinases. While some of these fusion events have shown utility in arriving at a precise diagnosis, novel fusions in otherwise difficult to classify sarcomas continue to be identified. We present a case of a 40-year-old female who noted a lower back nodule in 2010 that was initially labeled as a dermatofibrosarcoma protuberans with fibrosarcomatous transformation. The lesion recurred the following year and metastasized to the groin 6 years later. Because of some morphologic peculiarities, molecular characterization was pursued in the metastatic focus, which revealed the neoplasm was negative for the COL1A1-PDGFB fusion. However, anchored multiplex polymerase chain reaction for targeted next-generation sequencing (Archer Dx) detected an EML4-NTRK3 fusion, which was confirmed by reverse transcription-PCR, Sanger sequencing and RNA sequencing analysis of the recurrent and metastatic specimens. Although various soft tissue neoplasms involving fusions with NTRK genes are well-reported, the current case could not be easily classified in any of the established entities. Nevertheless, it raises interesting questions regarding the importance of classification, prognosis, and treatment for some of these tyrosine kinase fusion-driven sarcomas.


Assuntos
Proteínas de Ciclo Celular , Dermatofibrossarcoma , Receptor com Domínio Discoidina 2 , Proteínas Associadas aos Microtúbulos , Proteínas de Fusão Oncogênica , Serina Endopeptidases , Neoplasias Cutâneas , Adulto , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Dermatofibrossarcoma/genética , Dermatofibrossarcoma/metabolismo , Dermatofibrossarcoma/patologia , Receptor com Domínio Discoidina 2/genética , Receptor com Domínio Discoidina 2/metabolismo , Feminino , Humanos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
6.
Cancer Inform ; 13(Suppl 5): 129-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25991908

RESUMO

Whole transcriptome shotgun sequencing (RNA-Seq) is a useful tool for analyzing the transcriptome of a biological sample. With appropriate statistical and bioinformatic processing, this platform is capable of identifying significant differences in gene expression within the transcriptome and permits pathway and network analyses to determine how these genes interact biologically. In this study, we examined gene expression in two lung adenocarcinoma cell lines (H358 and A459) that were treated with transforming growth factor-ß (TGF-ß) as a model for induction of the epithelial-to-mesenchymal transition (EMT), commonly associated with disease progression. We performed this study in order to illustrate a workflow for identifying interesting genes and processes that are regulated early in EMT and to determine their gene pathway/network relationships and regulation. With this, we identified 137 upregulated and 32 downregulated genes common to both cell lines after TGF-ß treatment that represent components of multiple canonical pathways and biological networks associated with the induction of EMT. These findings were also verified against reposited Affymetrix U133a expression profiles from multiple trials examining metastatic progression in patient cohorts (n = 731 total) to further establish the clinical relevance and translational significance of the model system. Together, these findings help validate the relevance of the TGF-ß model for the study of EMT and provide new insights into early events in EMT.

7.
Ann Thorac Surg ; 92(5): 1805-11; discussion 1811, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21945224

RESUMO

BACKGROUND: Insulin-like growth factor 1 (IGF-I), IGF binding proteins (IGFBP) 1 to 7, and C-peptide have been postulated to predict survival in non-small cell lung cancer (NSCLC). Studying serum levels in NSCLC patients treated with surgical resection may provide information on the aggressiveness of tumors and be predictive of disease recurrence. METHODS: Immunobead assays were used to measure pretreatment serum levels of IGF-I, IGFBP1 to IGFBP7, and C-peptide in 100 NSCLC patients. Of these, 59 had no metastatic progression (T1 to T4 N0 M0), whereas 41 had positive lymph nodes (T1 to T4 N1 to N3 M0). Data were analyzed using the Mann-Whitney two-sided rank sum test or Kaplan-Meier curves. RESULTS: Low serum IGFBP5 levels correlated strongly with a positive nodal status (p < 0.001) and any incidence of disease recurrence (p = 0.003). Low serum levels of IGFBP5 also predicted poor recurrence-free survivals in the overall cohort (p ≤ 0.001) and in patients with no nodal metastases (p = 0.027). Conversely, a high serum level of IGFBP7 correlated with positive nodal status (p = 0.008), but was not prognostic for recurrence-free survival. No significant correlations were found for IGFBP5 or IGFBP7 for sex, age, race, smoking history, tumor histology, or fasting state. CONCLUSIONS: IGFBP5 and IGFBP7 had value as biomarkers for identifying NSCLC progression and patient outcome.


Assuntos
Peptídeo C/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Neoplasias Pulmonares/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
8.
J Thorac Oncol ; 4(3): 338-47, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19190517

RESUMO

INTRODUCTION: In non-small cell lung cancer (NSCLC), the presence of locoregional lymph node metastases remains the most important prognostic factor and significantly guides treatment regimens. Unfortunately, currently-available noninvasive staging modalities have limited accuracy. The objective of this study was to create a multianalyte blood test capable of discriminating a patient's true (pathologic) nodal status preoperatively. METHODS: Pretreatment serum specimens collected from 107 NSCLC patients with localized disease were screened with 47 biomarkers implicated in disease presence or progression. Multivariate statistical algorithms were then used to identify the optimal combination of biomarkers for accurately discerning each patient's nodal status. RESULTS: We identified 15 candidate biomarkers that met our criteria for statistical relevance in discerning a patient's preoperative nodal status. A 'random forest' classification algorithm was used with these parameters to define a 6-analyte panel, consisting of macrophage inflammatory protein-1alpha, carcinoembryonic antigen, stem cell factor, tumor necrosis factor-receptor I, interferon-gamma, and tumor necrosis factor-alpha, that was the optimum combination of biomarkers for identifying a patient's pathologic nodal status. A Classification and Regression Tree analysis was then created with this panel that was capable of correctly classifying 88% of the patients tested, relative to the pathologic assessments. This value is in contrast to our observed 85% classification rate using conventional clinical methods. CONCLUSIONS: This study establishes a serum biomarker panel with efficacy in discerning preoperative nodal status. With further validation, this blood test may be useful for assessing nodal status (including occult disease) in NSCLC patients facing tumor resection therapy.


Assuntos
Biomarcadores Tumorais/classificação , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/secundário , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Área Sob a Curva , Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Estudos de Coortes , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Pneumonectomia/métodos , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Medição de Risco , Sensibilidade e Especificidade , Taxa de Sobrevida , Adulto Jovem
9.
Pediatr Nephrol ; 21(4): 588-90, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16511686

RESUMO

Renal function was studied in a 7-year-old girl with Rett syndrome (RS) complicated by persistent hyperchloremic hyperkalemic metabolic acidosis. The acidosis was associated with a urine pH above 5.5, positive urinary anion gap and decreased potassium excretion. Plasma renin activity, aldosterone and cortisol levels were normal. Therapy with sodium bicarbonate failed to lower urine pH below 5.5 or increase potassium excretion. Hydrochlorothiazide administration resulted in a fall in urine pH below 5.5 and an increase in potassium excretion as a result of increased distal sodium delivery and increased sodium reabsorption in the distal nephron. We conclude that a voltage-dependent type of derangement in the distal nephron, rather than aldosterone deficiency, is responsible for the impairment in urinary acidification observed in this patient. Early detection of impaired renal acidification in RS may prevent or slow the progression of growth failure.


Assuntos
Acidose Tubular Renal/complicações , Hiperpotassemia/complicações , Síndrome de Rett/complicações , Criança , Feminino , Humanos
10.
BMC Urol ; 5: 3, 2005 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-15771771

RESUMO

BACKGROUND: As the voiding habits of Iranian children differs from other children because of some cultural and religious considerations, we aimed to establish normal reference values of urinary flow rates in Iranian children between 7 to 14 years of age. METHODS: Eight hundred and two uroflowmetry studies were performed on children with no history of a renal, urological, psychological or neurological disorder, between the ages 7 and 14. Five hundred twenty five studies from 192 girls and 335 boys were considered in this study excluding the staccato/interrupted voiding pattern or voided volume less than 20 ml. The voiding volume, the maximum and average urinary flow rates were extensively analyzed. RESULTS: The maximal and average urine flow rate nomograms were plotted for both girls and boys. Mean maximum urine flow rate was 19.9 (ml/sec) for boys and 23.5 (ml/sec) for girls with a mean voided volume of 142 (ml) for boys and 147 (ml) for girls. Flow rates showed a close association with voiding volume in both sexes. The maximum and average flow rates were higher in girls than in boys, and they showed a significant increase in flow rates with increasing age, where boys did not. The mean maximum urine flow rates (19.9 ml/sec for boys and 23.5 ml/sec for girls) were found to be higher in this study than other studies. CONCLUSION: Nomograms of maximal and average flow rates of girls and boys are presented in centile form, which can help the physician to evaluate the response to medical or surgical treatment and be useful for the screening of lower urinary tract disturbances in children, for a wide range of voided volumes.


Assuntos
Nomogramas , Micção/fisiologia , Urodinâmica , Adolescente , Criança , Feminino , Humanos , Irã (Geográfico) , Masculino , Valores de Referência , Urina
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