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1.
Heart Lung Circ ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38692982

RESUMO

Hospitalisations for heart failure (HF) are associated with high rates of readmission and death, the most vulnerable period being within the first few weeks post-hospital discharge. Effective transition of care from hospital to community settings for patients with HF can help reduce readmission and mortality over the vulnerable period, and improve long-term outcomes for patients, their family or carers, and the healthcare system. Planning and communication underpin a seamless transition of care, by ensuring that the changes to patients' management initiated in hospital continue to be implemented following discharge and in the long term. This evidence-based guide, developed by a multidisciplinary group of Australian experts in HF, discusses best practice for achieving appropriate and effective transition of patients hospitalised with HF to community care in the Australian setting. It provides guidance on key factors to address before and after hospital discharge, as well as practical tools that can be used to facilitate a smooth transition of care.

2.
Cytometry A ; 101(5): 448-457, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35099119

RESUMO

The morphology and other phenotypic characteristics of erythrocytes in sickle cell disease (SCD) have been analyzed for decades in patient evaluation. This involves a variety of techniques, including microscopic analysis of stained blood films, flow cytometry, and cell counting. Here, we analyzed SCD blood using imaging flow cytometry (IFC), a technology that combines flow cytometry and microscopy to enable simultaneous rapid-throughput analysis of cellular morphology and cell-surface markers. With IFC, we were able to automate quantification of poikilocytes from SCD blood. An important subpopulation of poikilocytes represented dense cells, although these could not be distinguished from other poikilocytes without first centrifuging the blood through density gradients. In addition, CD71-positive RBCs from SCD patients had two subpopulations: one with high CD71 expression and a puckered morphology and another with lower CD71 expression and biconcave morphology and presumably representing a later stage of differentiation. Some RBCs with puckered morphologies that were strongly positive for DAPI and CD49d were in fact nucleated RBCs. IFC identified more phosphatidylserine-expressing red cells in SCD than did conventional flow cytometry and these could also be divided into two subpopulations. One population had diffuse PS expression and appeared to be composed primarily of RBC ghosts; the other had lower overall PS expression present in intense, punctate dots overlying Howell-Jolly bodies. This study demonstrates that IFC can rapidly reveal and quantify RBC features in SCD that require numerous tedious methods to identify conventionally. Thus, IFC is likely to be a useful technique for evaluating and monitoring SCD.


Assuntos
Anemia Falciforme , Eritrócitos , Anemia Falciforme/metabolismo , Inclusões Eritrocíticas , Citometria de Fluxo/métodos , Humanos , Microscopia
3.
PLoS Pathog ; 15(6): e1007849, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31166996

RESUMO

Virus-host interactions are frequently studied in bulk cell populations, obscuring cell-to-cell variation. Here we investigate endogenous herpesvirus gene expression at the single-cell level, combining a sensitive and robust fluorescent in situ hybridization platform with multiparameter flow cytometry, to study the expression of gammaherpesvirus non-coding RNAs (ncRNAs) during lytic replication, latent infection and reactivation in vitro. This method allowed robust detection of viral ncRNAs of murine gammaherpesvirus 68 (γHV68), Kaposi's sarcoma associated herpesvirus and Epstein-Barr virus, revealing variable expression at the single-cell level. By quantifying the inter-relationship of viral ncRNA, viral mRNA, viral protein and host mRNA regulation during γHV68 infection, we find heterogeneous and asynchronous gene expression during latency and reactivation, with reactivation from latency identified by a distinct gene expression profile within rare cells. Further, during lytic replication with γHV68, we find many cells have limited viral gene expression, with only a fraction of cells showing robust gene expression, dynamic RNA localization, and progressive infection. Lytic viral gene expression was enhanced in primary fibroblasts and by conditions associated with enhanced viral replication, with multiple subpopulations of cells present in even highly permissive infection conditions. These findings, powered by single-cell analysis integrated with automated clustering algorithms, suggest inefficient or abortive γHV infection in many cells, and identify substantial heterogeneity in viral gene expression at the single-cell level.


Assuntos
Gammaherpesvirinae/fisiologia , Regulação Viral da Expressão Gênica/fisiologia , Infecções por Herpesviridae/metabolismo , RNA Mensageiro/biossíntese , RNA não Traduzido/biossíntese , RNA Viral/biossíntese , Replicação Viral/fisiologia , Animais , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/patologia , Humanos , Camundongos , Camundongos Knockout , RNA Mensageiro/genética , RNA não Traduzido/genética , RNA Viral/genética
4.
Anal Chem ; 92(5): 3535-3543, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-31999432

RESUMO

Immunoassays are important for the detection of proteins to enable disease identification and monitor treatment, but many immunoassays suffer from sensitivity limitations. The development of digital assays has enabled highly sensitive biomarker detection and quantification, but the necessary devices typically require precisely controlled volumes to reduce biases in concentration estimates from compartment size variation. These constraints have led to systems that are often expensive, cumbersome, and challenging to operate, confining many digital assays to centralized laboratories. To overcome these limitations, we have developed a simplified digital immunoassay performed in polydisperse droplets that are prepared without any specialized equipment. This polydisperse digital droplet immunoassay (ddIA) uses proximity ligation to remove the need for wash steps and simplifies the system to a single reagent addition step. Using interleukin-8 (IL-8) as an example analyte, we demonstrated the concept with samples in buffer and diluted whole blood with limits of detection of 0.793 pM and 1.54 pM, respectively. The development of a one-pot, washless assay greatly improves usability compared to traditional immunoassays or digital-based systems that rely heavily on wash steps and can be run with common and readily available laboratory equipment such as a heater and simple fluorescent microscope. We also developed a stochastic model with physically meaningful parameters that can be utilized to optimize the assay and enable quantification without standard curves, after initial characterization of the parameters. Our polydisperse ddIA assay serves as an example of sensitive, lower-cost, and simpler immunoassays suitable for both laboratory and point-of-care applications.


Assuntos
Imunoensaio/instrumentação , Dispositivos Lab-On-A-Chip , Interleucina-8/análise , Limite de Detecção
5.
J Minim Invasive Gynecol ; 27(7): 1581-1587.e1, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32126302

RESUMO

STUDY OBJECTIVE: To evaluate the diagnostic accuracy of transvaginal ultrasound in predicting a laparoscopic, surgically assigned, revised American Society of Reproductive Medicine (ASRM) endometriosis stage. DESIGN: A multicenter, retrospective, diagnostic accuracy study. SETTING: The patients visited 1 of 2 academic gynecologic ultrasound units and underwent laparoscopy led by 1 of 6 surgeons in metropolitan Sydney, Australia, between 2016 and 2018. PATIENTS: Patients with suspected endometriosis (n = 204). INTERVENTIONS: Ultrasound followed by laparoscopy. MEASUREMENTS AND MAIN RESULTS: Surgical cases were identified. The preoperative ultrasound report and surgical operative notes were each used to retrospectively assign an ASRM score and stage. The breakdown of surgical findings was as follows: ASRM 0 (i.e., no endometriosis), 24/204 (11.8%); ASRM 1, 110/204 (53.9%); ASRM 2, 22/204 (10.8%); ASRM 3, 16/204 (7.8%); ASRM 4, 32 204 (15.7%). The overall accuracy of ultrasound in predicting the surgical ASRM stage was as follows: ASRM 1, 53.4%; ASRM 2, 93.8%; ASRM 3, 89.7%; ASRM 4, 93.1%; grouped ASRM 0, 1, and 2, 94.6%; and grouped ASRM 3 and 4 of 94.6%. Ultrasound had better test performance in higher disease stages. When the ASRM stages were dichotomized, ultrasound had sensitivity and specificity of 94.9% and 93.8%, respectively, for ASRM 0, 1, and 2 and of 93.8% and 94.9%, respectively, for ASRM 3 and 4. CONCLUSION: Ultrasound has high accuracy in predicting the mild, moderate, and severe ASRM stages of endometriosis and can accurately differentiate between stages when ASRM stages are dichotomized (nil/minimal/mild vs moderate/severe). This can have major positive implications on patient triaging at centers of excellence in minimally invasive gynecology for advanced-stage endometriosis.


Assuntos
Endometriose/diagnóstico , Doenças Peritoneais/diagnóstico , Medicina Reprodutiva/normas , Ultrassonografia/métodos , Vagina/diagnóstico por imagem , Adulto , Austrália , Progressão da Doença , Endocrinologia/organização & administração , Endocrinologia/normas , Endometriose/patologia , Endometriose/cirurgia , Feminino , Humanos , Laparoscopia/métodos , Laparoscopia/normas , Doenças Peritoneais/patologia , Doenças Peritoneais/cirurgia , Guias de Prática Clínica como Assunto/normas , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Prognóstico , Reprodutibilidade dos Testes , Medicina Reprodutiva/organização & administração , Estudos Retrospectivos , Sensibilidade e Especificidade , Sociedades Médicas , Ultrassonografia/normas , Adulto Jovem
6.
Cytometry A ; 95(9): 976-984, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31294512

RESUMO

Deleterious changes, collectively termed as storage lesions, alter the characteristics of red blood cell (RBC) morphology during in vitro storage. Due to gradual loss of cellular membrane, RBCs lose their original biconcave disk shape and begin a process of spherical deformation that is characterized by well-defined morphological criteria. At the spheroechinocyte stage, the structure of RBC is irreversibly damaged and lacks the elasticity necessary to efficiently deliver oxygen. Quantifying the prevalence of spheroechinocytes could provide an important morphological measure of the quality of stored blood products. Unlike the conventional RBC morphology characterization assay involving light microscopy, we introduce a label-free assay using imaging flow cytometry (IFC). The technique captures 100,000 images of a sample and calculates a relative measure of spheroechinocyte population in a fraction of the time required by the conventional method. A comparative method study, measuring a morphological index for 11 RCC units through storage, found that the two techniques measured similar trends with IFC reporting the metric at an average of 3.9% higher. We monitored 18 RCC units between Weeks 1 and 6 of storage and found that the spheroechinocyte population increased by an average of 26.2%. The large (3.5-64.1%) variation between the units' spheroechinocyte population percentage at Week 1 suggests a possible dependence of blood product quality on donor characteristics. Given our method's ability to rapidly monitor large samples and refine morphological characterization beyond conventional methods, we believe our technique offers good potential for studying the underlying relationships between RBC morphology and blood storage lesions. © 2019 International Society for Advancement of Cytometry.


Assuntos
Preservação de Sangue , Eritrócitos/citologia , Citometria de Fluxo/métodos , Deformação Eritrocítica , Humanos , Citometria por Imagem/métodos , Processamento de Imagem Assistida por Computador , Microscopia
7.
Analyst ; 144(24): 7209-7219, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31663521

RESUMO

In digital assays, devices are typically considered to require precisely controlled volumes since variation in compartment volumes causes biases in concentration estimates. To enable more possibilities in device design, we derived two methods to accurately calculate target concentrations from raw results when the compartment volume may vary and may not follow known parametrically described distributions. The Digital Variable Volume (dvv) method uses volumes of ON compartments (those with positive signals) and the total sample volume, while the Digital Variable Volume Approximation (dvva) method uses the number of ON compartments, the total number of compartments, and a set of separately measured volumes. We verified the trueness of the dvv and dvva methods using simulated assays where volumes followed an empirical distribution (based on measured droplet volumes) and well known distributions with a wide range of standard deviations. We applied both methods to digital PCR experiments with polydisperse volumes, and also derived equations to estimate standard errors and limits of detection. The dvv method allows the compartment volume to follow any distribution in each assay run, the dvva method allows for quantification without in-assay volume measurements, and both methods potentially enable new designs of digital assays.

8.
Chemotherapy ; 64(1): 17-21, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31167190

RESUMO

Prolonged intermittent renal replacement therapy (PIRRT) is an increasingly adopted method of renal replacement in critically ill patients. Like continuous renal replacement therapy, PIRRT can alter the pharmacokinetics (PK) of many drugs. In this setting, dosing data for antibiotics like benzylpenicillin are lacking. In order to enable clinicians to prescribe benzylpenicillin safely and effectively, knowledge of the effects of PIRRT on the plasma PK of benzylpenicillin is required. Herein, we describe the PK of benzylpenicillin in 2 critically ill patients on PIRRT for the treatment of penicillin-susceptible Staphylococcus aureus bacteremia complicated by infective endocarditis. Blood samples were taken for each patient taken over dosing periods during PIRRT and off PIRRT. Two-compartment PK models described significant differences in the mean clearance of benzylpenicillin with and without PIRRT (6.61 vs. 3.04 L/h respectively). We would suggest a benzylpenicillin dose of 1,800 mg (3 million units) every 6-h during PIRRT therapy as sufficient to attain PK/pharmacodynamic target.


Assuntos
Antibacterianos/farmacocinética , Penicilina G/farmacocinética , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteriemia/complicações , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Relação Dose-Resposta a Droga , Meia-Vida , Humanos , Masculino , Pessoa de Meia-Idade , Penicilina G/farmacologia , Penicilina G/uso terapêutico , Terapia de Substituição Renal , Sepse/complicações , Sepse/diagnóstico , Sepse/tratamento farmacológico , Sepse/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Resultado do Tratamento
9.
J Obstet Gynaecol Can ; 41(4): 443-449.e2, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30361156

RESUMO

OBJECTIVE: Knowledge of rectouterine cul-de-sac state and consistent classification among surgeons are important in the surgical management of women with endometriosis. The objective of this study was to determine the diagnostic accuracy and interobserver and intraobserver agreement among general gynaecologists (GGs) and minimally invasive gynaecologic surgeons (MIGSs) in the prediction of cul-de-sac obliteration at off-line analysis of laparoscopic videos. METHODS: Five GGs and five MIGSs viewed 33 prerecorded laparoscopic video sets off-line to determine cul-de-sac obliteration state (non-obliterated, partially obliterated, or completely obliterated) on two occasions (at least 7days apart). Diagnostic accuracy and interobserver and intraobserver agreement were evaluated. RESULTS: The interobserver agreements for all 10 observers for the description of cul-de-sac state ranged from fair to substantial agreement, with moderate overall agreement. MIGSs had slightly higher within-group interobserver agreement compared with GGs. MIGSs achieved overall almost perfect intraobserver agreement compared with substantial agreement for GGs. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for MIGSs classifying the cul-de-sac state were 83.9%, 88.5%, 88.5%, 89.2%, 92.0%, and 84.7%, respectively, whereas for GGs, they were 79.1%, 79.4%, 88.1%, 89.9%, and 76.1%, respectively. CONCLUSION: Diagnostic accuracy and interobserver and intraobserver agreement for cul-de-sac obliteration state classification is acceptable in both groups. MIGSs had greater diagnostic accuracy and exhibited high interobserver and intraobserver agreement, a finding suggesting that their advanced training makes them more reliable in cul-de-sac obliteration assessment. Partial cul-de-sac obliteration was the most commonly incorrectly diagnosed state, thus implying that partial obliteration is not well understood.


Assuntos
Escavação Retouterina/patologia , Endometriose/cirurgia , Complicações Pós-Operatórias/diagnóstico , Procedimentos Cirúrgicos de Citorredução , Endometriose/patologia , Feminino , Ginecologia , Humanos , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/cirurgia , Reprodutibilidade dos Testes , Cirurgiões , Gravação em Vídeo
10.
Anal Chem ; 90(15): 9374-9380, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29985594

RESUMO

Nucleic acid amplification technology, such as polymerase chain reaction (PCR), has enabled highly sensitive and specific disease detection and quantification, leading to more accurate diagnosis and treatment regimens. Lab-on-a-chip applications have developed methods to partition single biomolecules, such as DNA and RNA, into picoliter-sized droplets. These individual reaction vessels lead to digitization of PCR enabling improved time to detection and direct quantification of nucleic acids without a standard curve, therefore simplifying assay analysis. Though impactful, these improvements have generally been restricted to centralized laboratories with trained personnel and expensive equipment. To address these limitations and make this technology more applicable for a variety of settings, we have developed a statistical framework to apply to droplet PCR performed in polydisperse droplets prepared without any specialized equipment. The polydisperse droplet system allows for accurate quantification of droplet digital PCR (ddPCR) and reverse transcriptase droplet digital PCR (RT-ddPCR) that is comparable to commercially available systems such as BioRad's ddPCR. Additionally, this approach is compatible with a range of input sample volumes, extending the assay dynamic range beyond that of commercial ddPCR systems. In this work, we show that these ddPCR assays can reduce overall assay time while still providing quantitative results. We also report a multiplexed ddPCR assay and demonstrate proof-of-concept methods for rapid droplet preparation in multiple samples simultaneously. Our simple polydisperse droplet preparation and statistical framework can be extended to a variety of settings for the quantification of nucleic acids in complex samples.


Assuntos
Dispositivos Lab-On-A-Chip , Reação em Cadeia da Polimerase/métodos , DNA/análise , Emulsões , RNA/análise
11.
J Cell Biochem ; 118(12): 4414-4424, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28452069

RESUMO

Tumor-derived extracellular vesicles (EVs) are emerging as an important mode of intercellular communication, capable of transferring biologically active molecules that facilitate the malignant growth and metastatic process. CD133 (Prominin-1), a stem cell marker implicated in tumor initiation, differentiation and resistance to anti-cancer therapy, is reportedly associated with EVs in various types of cancer. However, little is known about the factors that regulate the release of these CD133+ EVs. Here, we report that the HDAC6 inhibitor tubacin promoted the extracellular release of CD133+ EVs from human FEMX-I metastatic melanoma and Caco-2 colorectal carcinoma cells, with a concomitant downregulation of intracellular CD133. This effect was specific for tubacin, as inhibition of HDAC6 deacetylase activity by another selective HDAC6 inhibitor, ACY-1215 or the pan-HDAC inhibitor trichostatin A (TSA), and knockdown of HDAC6 did not enhance the release of CD133+ EVs. The tubacin-induced EV release was associated with changes in cellular lipid composition, loss of clonogenic capacity and decrease in the ability to form multicellular aggregates. These findings indicate a novel potential anti-tumor mechanism for tubacin in CD133-expressing malignancies. J. Cell. Biochem. 118: 4414-4424, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Antígeno AC133/metabolismo , Anilidas/farmacologia , Micropartículas Derivadas de Células/metabolismo , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Linhagem Celular Tumoral , Desacetilase 6 de Histona/metabolismo , Humanos
13.
Anal Chem ; 82(23): 9959-61, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21033750

RESUMO

A microfabricated device is described for the capture and injection of a single mammalian cell into a fused silica capillary for subsequent analysis by chemical cytometry. The device consists of a 500 µm diameter well made from polydimethylsiloxane on an indium-tin oxide coated microscope slide. The bottom of the well contains a 2 µm high aperture, which was designed to block passage of cells. A cellular suspension was allowed to settle on the device, and aspiration through the aperture was used to trap a single NG-108 cell. Untrapped cells were washed from the device, and a 150 µm outer diameter and 50 µm inner diameter capillary was placed in the well. To inject a cell, voltage was applied to the indium-tin oxide while simultaneously applying vacuum at the distal end of the capillary.


Assuntos
Eletroforese Capilar/métodos , Dióxido de Silício/química , Compostos de Estanho/química , Animais , Linhagem Celular Tumoral , Dimetilpolisiloxanos/química , Eletroforese Capilar/instrumentação , Lasers , Camundongos , Ratos , Rodaminas/química , Compostos de Estanho/farmacologia
14.
J Endourol ; 34(2): 139-144, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31663371

RESUMO

Background and Purpose: Classically, abdominal X-ray (KUB), ultrasound, or a combination of both have been routinely used for ureteral stone surveillance after initial diagnosis. More recently, ultra-low-dose CT (ULD CT) has emerged as a CT technique that reduces radiation dose while maintaining high sensitivity and specificity for urinary stone detection. We aim to evaluate our initial experience with ULD CT for patients with ureterolithiasis, measuring real-world radiation doses and stone detection performance. Methods: We reviewed all ULD CT scans performed at the Veterans Affairs Palo Alto Health Care System between 2016 and 2018. We included patients with ureteral stones and calculated the mean effective radiation dose per scan. We determined stone location and size, if the stone was visible on the associated KUB or CT scout film, and if hydronephrosis was present. We performed logistic regression to identify variables associated with visibility on KUB or CT scout film and hydronephrosis. Results: One hundred eighteen ULD scans were reviewed, of which 50 detected ureteral stones. The mean effective radiation dose was 1.04 ± 0.41 mSv. Of the ULD CTs that detected ureterolithiasis, 38% lacked visibility on KUB/CT scout film and had no associated hydronephrosis, suggesting that they would be missed with a combination of KUB and ultrasound. Larger stones (odds ratio [OR]: 1.40, 95% confidence interval [CI]: 1.08, 1.96 for every 1 mm increase in stone size) were more likely to be detected by KUB/CT scout film or ultrasound, while stones in the distal ureter (OR: 0.18, 95% CI: 0.03, 0.81) were more likely to be missed by KUB/CT scout film or hydronephrosis. Conclusions: Based on our institutions' initial experience, ULD CT detects small and distal ureteral stones that would likely be missed by KUB or ultrasound, while maintaining a low effective radiation dose. An ULD CT protocol should be considered when reimaging for ureteral stones is necessary.


Assuntos
Hidronefrose/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Cálculos Ureterais/diagnóstico por imagem , Cálculos Urinários/diagnóstico por imagem , Urolitíase/diagnóstico por imagem , Idoso , Feminino , Seguimentos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Radiografia Abdominal , Sensibilidade e Especificidade , Ureter/diagnóstico por imagem , Cálculos Ureterais/terapia , Urolitíase/terapia
15.
J Microbiol Immunol Infect ; 40(3): 201-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17639159

RESUMO

BACKGROUND AND PURPOSE: Agaricus blazei Murill has been reported to possess biological effects that include immunomodulatory and tumoricidal activities, but its potential effects have not been systematically analyzed in vivo. We evaluated the immunomodulatory effects of A. blazei in Balb/cByJ mice. METHODS: 160 male Balb/cByJ mice were divided into four groups and treated with various quantities of intragastric A. blazei extract or distilled water for 8 to 10 weeks. Nine parameters, relating to general immune function or adaptive immunity against immunogen chicken oval albumin, were determined. RESULTS: The results revealed that mice receiving A. blazei extract exhibited significantly greater serum immunoglobulin G levels, increased T-cell numbers in spleen, and elevated phagocytic capability compared with controls. Consumption of A. blazei was also associated with significant increases in oval albumin-specific serum immunoglobulin G level, delayed-type hypersensitivity, splenocyte proliferation rate, and tumor necrosis factor-alpha secretion by splenocytes. CONCLUSIONS: Consumption of A. blazei extract was associated with significant enhancement of seven out of nine immune functions tested. We conclude that A. blazei Murill possesses a wide range of immunomodulatory effects in vivo.


Assuntos
Agaricus/imunologia , Sistema Imunitário/fisiopatologia , Fatores Imunológicos , Animais , Hipersensibilidade Tardia/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Fagocitose , Baço/imunologia , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/metabolismo
16.
Biomicrofluidics ; 10(2): 024122, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27158290

RESUMO

Microfluidic devices can deliver soluble factors to cell and tissue culture microenvironments with precise spatiotemporal control. However, enclosed microfluidic environments often have drawbacks such as the need for continuous culture medium perfusion which limits the duration of experiments, incongruity between microculture and macroculture, difficulty in introducing cells and tissues, and high shear stress on cells. Here, we present an open-chamber microfluidic device that delivers hydrodynamically focused streams of soluble reagents to cells over long time periods (i.e., several hours). We demonstrate the advantage of the open chamber by using conventional cell culture techniques to induce the differentiation of myoblasts into myotubes, a process that occurs in 7-10 days and is difficult to achieve in closed chamber microfluidic devices. By controlling the flow rates and altering the device geometry, we produced sharp focal streams with widths ranging from 36 µm to 187 µm. The focal streams were reproducible (∼12% variation between units) and stable (∼20% increase in stream width over 10 h of operation). Furthermore, we integrated trenches for micropatterning myoblasts and microtraps for confining single primary myofibers into the device. We demonstrate with finite element method (FEM) simulations that shear stresses within the cell trench are well below values known to be deleterious to cells, while local concentrations are maintained at ∼22% of the input concentration. Finally, we demonstrated focused delivery of cytoplasmic and nuclear dyes to micropatterned myoblasts and myofibers. The open-chamber microfluidic flow-focusing concept combined with micropatterning may be generalized to other microfluidic applications that require stringent long-term cell culture conditions.

17.
Lab Chip ; 15(8): 1934-41, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25738695

RESUMO

Microfluidic automation - the automated routing, dispensing, mixing, and/or separation of fluids through microchannels - generally remains a slowly-spreading technology because device fabrication requires sophisticated facilities and the technology's use demands expert operators. Integrating microfluidic automation in devices has involved specialized multi-layering and bonding approaches. Stereolithography is an assembly-free, 3D-printing technique that is emerging as an efficient alternative for rapid prototyping of biomedical devices. Here we describe fluidic valves and pumps that can be stereolithographically printed in optically-clear, biocompatible plastic and integrated within microfluidic devices at low cost. User-friendly fluid automation devices can be printed and used by non-engineers as replacement for costly robotic pipettors or tedious manual pipetting. Engineers can manipulate the designs as digital modules into new devices of expanded functionality. Printing these devices only requires the digital file and electronic access to a printer.


Assuntos
Dispositivos Lab-On-A-Chip , Impressão Tridimensional , Animais , Automação , Células CHO , Cálcio/metabolismo , Cricetinae , Cricetulus , Membranas Artificiais , Imagem Molecular
18.
Technology (Singap World Sci) ; 3(4): 163-171, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27158641

RESUMO

We developed micromolded microwell arrays to study the proliferation and senescence of single cells. Microwell arrays were designed to be compatible with conventional cell culture protocols to simplify cell loading, cell culture, and imaging. We demonstrated the utility of these arrays by measuring the proliferation and senescence of isogenic cells which expressed or had been depleted of the human Werner syndrome protein. Our results allowed us to reveal cell-to-cell heterogeneity in proliferation in WRN+ and WRN-depleted fibroblasts during clonal growth.

19.
Cancer Gene Ther ; 9(9): 778-86, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12189528

RESUMO

The present study uses an in vivo murine tumor model expressing the human HER-2/neu antigen to evaluate the potential vaccine using dendritic cells (DCs) infected with adenovirus AdVHER-2. We first investigated whether infected DCs (DC(HER-2)) engineered to express HER-2/neu could induce HER-2/neu-specific immune responses. Our data showed that (i) AdVHER2-infected DC(HER-2) expressed HER-2/neu by Western blot and flow cytometric analysis, and (ii) vaccination of mice with DC(HER-2) induced HER-2/neu-specific cytotoxic T-lymphocyte (CTL) responses, but protected only 25% of vaccinated mice from challenge of 3 x 10(5) MCA26/HER-2 tumor cells. Further, to enhance the efficacy of DC(HER-2) vaccine, we coinfected DCs with both AdVHER-2 and AdVTNF-alpha. The infected DCs (DC(HER-2/TNF-alpha)) displayed the expression of both HER-2/neu and TNF-alpha by flow cytometric and ELISA analysis. We next investigated whether DC(HER-2/TNF-alpha) could induce stronger HER-2/neu-specific immune responses. We found that DC(HER-2/TNF-alpha) displayed up-regulation of immunologically important CD40, CD86, and ICAM-I molecules compared with DC(HER-2), indicating that the former ones are more mature forms of DCs. Vaccination of DC(HER-2/TNF-alpha) induced stronger allogeneic T-cell proliferation and 36% enhanced HER-2/neu-specific T-cell responses in vitro than DC(HER-2) cells. More importantly, it stimulated the significant anti-HER-2/neu immunity in vivo, which protected 8/8 mice from challenge of 3 x 10(5) MCA26/HER-2 tumor cells. Therefore, DCs genetically engineered to express both the tumor antigen and cytokines such as TNF-alpha as an immunoadjuvant are likely to represent a new direction in DC vaccine of cancer.


Assuntos
Células Dendríticas/imunologia , Neoplasias Experimentais/terapia , Receptor ErbB-2/genética , Transdução Genética , Fator de Necrose Tumoral alfa/genética , Adenoviridae/genética , Animais , Western Blotting , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Testes Imunológicos de Citotoxicidade , Primers do DNA/química , Células Dendríticas/virologia , Feminino , Citometria de Fluxo , Vetores Genéticos , Molécula 1 de Adesão Intercelular/metabolismo , Óperon Lac , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/imunologia , Receptor ErbB-2/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Fator de Necrose Tumoral alfa/imunologia
20.
Lab Chip ; 14(23): 4540-51, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25275698

RESUMO

There is a critical unmet need to tailor chemotherapies to individual patients. Personalized approaches could lower treatment toxicity, improve the patient's quality of life, and ultimately reduce mortality. However, existing models of drug activity (based on tumor cells in culture or animal models) cannot accurately predict how drugs act in patients in time to inform the best possible treatment. Here we demonstrate a microfluidic device that integrates live slice cultures with an intuitive multiwell platform that allows for exposing the slices to multiple compounds at once or in sequence. We demonstrate the response of live mouse brain slices to a range of drug doses in parallel. Drug response is measured by imaging of markers for cell apoptosis and for cell death. The platform has the potential to allow for identifying the subset of therapies of greatest potential value to individual patients, on a timescale rapid enough to guide therapeutic decision-making.


Assuntos
Ensaios de Seleção de Medicamentos Antitumorais/instrumentação , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Técnicas Analíticas Microfluídicas/instrumentação , Animais , Antineoplásicos/farmacologia , Encéfalo/efeitos dos fármacos , Química Encefálica , Linhagem Celular Tumoral , Desenho de Equipamento , Glioblastoma/patologia , Humanos , Camundongos , Técnicas Analíticas Microfluídicas/métodos
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