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1.
Lasers Surg Med ; 52(1): 84-87, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31736123

RESUMO

BACKGROUND AND OBJECTIVES: Actinic keratoses (AK) are common pre-cancerous lesions, which are associated with ultraviolet light exposure and aging. Wounding therapies such as fractionated laser resurfacing (FLR) have been previously demonstrated to effectively treat facial AK. However, the effectiveness of FLR on other sites commonly afflicted with AK has not been studied in detail. Previously, our group has reported that treatment of aged skin with wounding therapies including dermabrasion and ablative fractionated resurfacing results in the removal of senescent fibroblasts and normalizing the pro-carcinogenic acute ultraviolet B radiation responses associated with aged skin. The current studies were designed to test the effectiveness of FLR of the forearm skin of subjects aged 60 and older to remove AKs. STUDY DESIGN/MATERIALS AND METHODS: Between February 2018 and March 2019, 30 subjects were enrolled in a study, in which they underwent a single FLR treatment of one extremity including the dorsal forearm, wrist, and dorsal hand. The number of AKs was recorded on both extremities at baseline, 3 and 6 months in a blinded fashion. Side effects of the FLR were documented. RESULTS: A single FLR treatment resulted in a 62% reduction in the absolute number of AK in the treated arm at 6 months post-treatment. The laser treatment was well-tolerated without major complications. CONCLUSIONS: These studies demonstrate that FLR using settings, which have demonstrated to remove senescent fibroblasts and normalize the pro-carcinogenic UVB-response of aged skin is a potentially effective and safe field therapy treatment that should be studied for long-term efficacy for use in treating upper extremity AKs. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.


Assuntos
Ceratose Actínica/radioterapia , Terapia com Luz de Baixa Intensidade , Fatores Etários , Idoso , Seguimentos , Antebraço , Humanos , Ceratose Actínica/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
2.
Arch Orthop Trauma Surg ; 140(4): 449-455, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31392407

RESUMO

PURPOSE: To determine the factors that influence radiation exposure during repair of supracondylar humerus fractures. METHODS: Medical records of almost 200 children with supracondylar fractures were retrospectively analyzed for variables correlated with fluoroscopy time and radiation dose as measures of radiation exposure. RESULTS: There was no statistically significant difference in fluoroscopy time (27 vs. 22 s p = 0.345) or direct radiation dose (0.394 vs. 0.318 mSv p = 0.290) between uniplanar and biplanar C-arm use. No statistically significant differences in fluoroscopy time or radiation dose were found for surgical technique, comorbid ipsilateral fractures, preoperative neurovascular compromise, or resident participation. There was a significant 8.3 s increase in fluoroscopy time (p = 0.022) and 0.249 mSv increase in radiation dose (p = 0.020) as the fracture type increased from II to III. An increase in one pin during CRPP resulted in a statistically significant 10.4 s increase in fluoroscopy time and a 0.205 mSv increase in radiation dose. There were significant differences between the physician with the lowest fluoroscopy time and radiation dose compared with the physicians with the two highest values for both fluoroscopy time and radiation dose (p < 0.01). CONCLUSIONS: We found no significant difference in direct radiation exposure or fluoroscopy time when comparing biplanar to uniplanar C-arm use, resident participation, preoperative neurovascular compromise, or for comorbid ipsilateral fractures. Both outcomes increased significantly as fracture type increased from II to III and as the number of pins used during CRPP increased. Both outcomes were significantly different between the surgeons performing CRPP.


Assuntos
Fluoroscopia , Fraturas do Úmero , Exposição à Radiação , Criança , Fluoroscopia/efeitos adversos , Fluoroscopia/estatística & dados numéricos , Fixação de Fratura/efeitos adversos , Fixação de Fratura/métodos , Fixação de Fratura/estatística & dados numéricos , Humanos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Úmero/diagnóstico por imagem , Úmero/cirurgia , Exposição à Radiação/normas , Exposição à Radiação/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Tempo
3.
Proc Natl Acad Sci U S A ; 113(52): 14944-14948, 2016 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-27974610

RESUMO

This paper reports the results of a large-scale field experiment designed to test the hypothesis that group membership can increase participation and prosocial lending for an online crowdlending community, Kiva. The experiment uses variations on a simple email manipulation to encourage Kiva members to join a lending team, testing which types of team recommendation emails are most likely to get members to join teams as well as the subsequent impact on lending. We find that emails do increase the likelihood that a lender joins a team, and that joining a team increases lending in a short window (1 wk) following our intervention. The impact on lending is large relative to median lender lifetime loans. We also find that lenders are more likely to join teams recommended based on location similarity rather than team status. Our results suggest team recommendation can be an effective behavioral mechanism to increase prosocial lending.

4.
Clin Biochem ; 123: 110686, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992798

RESUMO

INTRODUCTION: Clinical laboratories in British Columbia, Canada implemented the CKD-EPI 2009 equation without the race variable for estimated glomerular filtration rate (eGFR) reporting since 2014. As more clinical laboratories adopt the new CKD-EPI 2021 equation, the study aims to compare these two race-free CKD-EPI eGFR equations using the laboratory data from a large tertiary hospital in BC and evaluate the impact on reclassification of eGFR category. METHODS: Serum/plasma creatinine results and demographic data were collected from Vancouver General Hospital laboratory. The CKD-EPI 2009 without the race variable and CKD-EPI 2021 equations were computed. eGFR and its distributions were compared and reclassification of eGFR category was assessed across the full cohort and in specific patient populations. RESULTS: The analysis included 58,763 patients. The median age was 57 years, with women comprising 51 % of the population. The median of eGFR changed from 85 to 90 mL/min/1.73 m2 using the CKD-EPI 2009 equation without the race variable and the CKD-EPI 2021 equation, respectively. The CKD-EPI 2021 equation reclassified 11.86 % of patients, mainly from G3a (45-59 mL/min/1.73 m2) to G2 (60-89 mL/min/1.73 m2). There was statistical significance between the non-renal and the renal population reclassified from G5 (<15 mL/min/1.73 m2) to G4 (15-29 mL/min/1.73 m2). CONCLUSIONS: Using laboratory data representative of local populations, we observed an overall positive shift to higher eGFR, with 11.86 % of individuals having improved eGFR categories based on the CKD-EPI 2021 equation. This study provides insights into clinical implications at both the individual and population levels. The data-based approach is the first step towards adopting the CKD-EPI 2021 equation within the province.


Assuntos
Falência Renal Crônica , Insuficiência Renal Crônica , Humanos , Feminino , Pessoa de Meia-Idade , Creatinina , Colúmbia Britânica/epidemiologia , Laboratórios Clínicos , Rim , Taxa de Filtração Glomerular , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia
5.
Clin Biochem ; 129: 110779, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38871043

RESUMO

The Hospital at Home (HaH) program has experienced accelerated growth in major Canadian provinces, driven in part by technological advancements and evolving patient needs during the COVID-19 pandemic. As an increasing number of hospitals pilot or implement these innovative programs, substantial resources have been allocated to support clinical teams. However, it is crucial to note that the vital roles played by clinical laboratories remain insufficiently acknowledged. This mini review aims to shed light on the diverse functions of clinical laboratories, spanning the preanalytical, analytical, and post-analytical phases within the HaH program context. Additionally, the review will explore recent advancements in clinical testing and the potential benefits of integrating new technologies into the HaH framework. Emphasizing the integral role of clinical laboratories, the discussion will address the current barriers hindering their active involvement, accompanied by proposed solutions. The capacity and efficiency of the HaH program hinge on sustained collaborative efforts from various teams, with clinical laboratories as crucial team players. Recognizing and addressing the specific challenges faced by clinical laboratories is essential for optimizing the overall performance and impact of the HaH initiative.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Canadá , SARS-CoV-2 , Pandemias , Laboratórios Clínicos , Serviços Hospitalares de Assistência Domiciliar/organização & administração , Pacientes Internados
6.
Sci Adv ; 9(51): eadj9964, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38134285

RESUMO

The study of molecular mechanisms at the single-cell level holds immense potential for enhancing immunotherapy and understanding neuroinflammation and neurodegenerative diseases by identifying previously concealed pathways within a diverse range of paired cells. However, existing single-cell pairing platforms have limitations in low pairing efficiency, complex manual operation procedures, and single-use functionality. Here, we report a multiparametric cellular immunity analysis by a modular acoustofluidic platform: CIAMAP. This platform enables users to efficiently sort and collect effector-target (i.e., NK92-K562) cell pairs and monitor the real-time dynamics of immunological response formation. Furthermore, we conducted transcriptional and protein expression analyses to evaluate the pathways that mediate effector cytotoxicity toward target cells, as well as the synergistic effect of doxorubicin on the cellular immune response. Our CIAMAP can provide promising building blocks for high-throughput quantitative single-cell level coculture to understand intercellular communication while also empowering immunotherapy by precision analysis of immunological synapses.


Assuntos
Imunidade Celular , Imunoterapia , Humanos , Células K562
7.
Open Heart ; 8(2)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34663746

RESUMO

INTRODUCTION: Patients with heart failure (HF) are classically categorised by left ventricular ejection fraction (LVEF). Efforts to predict outcomes and response to specific therapy among LVEF-based groups may be suboptimal, in part due to the underlying heterogeneity within clinical HF phenotypes. A multidimensional characterisation of ambulatory patients with and without HF across LVEF groups is needed to better understand and manage patients with HF in a more precise manner. METHODS AND ANALYSIS: To date, the first cohort of 1313 out of total planned 3000 patients with and without HF has been enroled in this single-centre, longitudinal observational cohort study. Baseline and 1-year follow-up blood samples and clinical characteristics, the presence and duration of comorbidities, serial laboratory, echocardiographic data and images and therapy information will be obtained. HF diagnosis, aetiology of disease, symptom onset and clinical outcomes at 1 and 5 years will be adjudicated by a team of clinicians. Clinical outcomes of interest include all-cause mortality, cardiovascular mortality, all-cause hospitalisation, cardiovascular hospitalisation, HF hospitalisation, right-sided HF and acute kidney injury. Results from the Preserved versus Reduced Ejection Fraction Biomarker Registry and Precision Medicine Database for Ambulatory Patients with Heart Failure (PREFER-HF) trial will examine longitudinal clinical characteristics, proteomic, metabolomic, genomic and imaging data to better understand HF phenotypes, with the ultimate goal of improving precision medicine and clinical outcomes for patients with HF. ETHICS AND DISSEMINATION: Information gathered in this research will be published in peer-reviewed journals. Written informed consent for PREFER-HF was obtained from all participants. All study procedures were approved by the Mass General Brigham Institutional Review Board in Boston, Massachusetts and performed in accordance with the Declaration of Helsinki (Protocol Number: 2016P000339). TRIAL REGISTRATION NUMBER: PREFER-HF ClinicalTrials.gov identifier: NCT03480633.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Medicina de Precisão/estatística & dados numéricos , Sistema de Registros , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Ecocardiografia , Seguimentos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Ventrículos do Coração/fisiopatologia , Humanos , Incidência , Massachusetts/epidemiologia , Estudos Prospectivos , Proteômica/métodos
8.
J Clin Invest ; 131(19)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34428179

RESUMO

BACKGROUNDThe loss of insulin-like growth factor 1 (IGF-1) expression in senescent dermal fibroblasts during aging is associated with an increased risk of nonmelanoma skin cancer (NMSC). We tested how IGF-1 signaling can influence photocarcinogenesis during chronic UVB exposure to determine if fractionated laser resurfacing (FLR) of aged skin, which upregulates dermal IGF-1 levels, can prevent the occurrence of actinic keratosis (AK) and NMSC.METHODSA human skin/immunodeficient mouse xenografting model was used to test the effects of a small molecule inhibitor of the IGF-1 receptor on chronic UVB radiation. Subsequently, the durability of FLR treatment was tested on a cohort of human participants aged 65 years and older. Finally, 48 individuals aged 60 years and older with considerable actinic damage were enrolled in a prospective randomized clinical trial in which they underwent a single unilateral FLR treatment of one lower arm. Numbers of AKs/NMSCs were recorded on both extremities for up to 36 months in blinded fashion.RESULTSXenografting studies revealed that chronic UVB treatment with a topical IGF-1R inhibitor resulted in a procarcinogenic response. A single FLR treatment was durable in restoring appropriate UVB response in geriatric skin for at least 2 years. FLR resulted in sustained reduction in numbers of AKs and decreased numbers of NMSCs in the treated arm (2 NMSCs) versus the untreated arm (24 NMSCs).CONCLUSIONThe elimination of senescent fibroblasts via FLR reduced the procarcinogenic UVB response of aged skin. Thus, wounding therapies are a potentially effective prophylaxis for managing high-risk populations.TRIAL REGISTRATIONClinicalTrials.gov (NCT03906253).FUNDINGNational Institutes of Health, Veterans Administration.


Assuntos
Ceratose Actínica/prevenção & controle , Terapia a Laser/métodos , Envelhecimento da Pele/efeitos da radiação , Neoplasias Cutâneas/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/fisiologia , Raios Ultravioleta
9.
Adv Mater ; 31(35): e1900453, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31270881

RESUMO

Allostasis is a fundamental biological process through which living organisms achieve stability via physiological or behavioral changes to protect against internal and external stresses, and ultimately better adapt to the local environment. However, an full understanding of cellular-level allostasis is far from developed. By employing an integrated micromechanical tool capable of applying controlled mechanical stress on an individual cell and simultaneously reporting dynamic information of subcellular mechanics, individual cell allostasis is observed to occur through a biphasic process; cellular mechanics tends to restore to a stable state through a mechanoadaptative process with excitative biophysical activity followed by a decaying adaptive phase. Based on these observations, it is found that cellular allostasis occurs through a complex balance of subcellular energy and cellular mechanics; upon a transient and local physical stimulation, cells trigger an allostatic state that maximizes energy and overcomes a mechanical "energy barrier" followed by a relaxation state that reaches its mechanobiological stabilization and energy minimization. Discoveries of energy-driven cellular machinery and conserved mechanotransductive pathways underscore the critical role of force-sensitive cytoskeleton equilibrium in cellular allostasis. This highlight the biophysical origin of cellular mechanical allostasis, providing subcellular methods to understand the etiology and progression of certain diseases or aging.


Assuntos
Alostase , Fenômenos Mecânicos , Fenômenos Biomecânicos , Cálcio/metabolismo , Linhagem Celular Tumoral , Citoesqueleto/metabolismo , Humanos , Termodinâmica
10.
J Allied Health ; 47(1): 35-44, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29504018

RESUMO

Past research has shown that there is a pattern of systematic grade inflation in higher education in the U.S. As a result, it is difficult for prospective employers and graduate school admission directors to distinguish bright candidates when recruiting new graduates. The purpose of this study was two-fold: 1) to determine the grading patterns of four academic departments (i.e., rehabilitation services, communication science and disorders, social work, and nursing) in an allied health college at a large public university over time, and 2) to consider which instructor demographic factors and course characteristics might influence the grading patterns. Using an archival data set, the grades for 1,892 course sections over 12 semesters were examined. The results showed that the Department of Social Work had the highest semester GPAs, and that approximately 20% of the variance in course GPAs was due to course characteristics, with instructor characteristics only explaining 3% of the variance. Implications and directions for future research are discussed.


Assuntos
Ocupações Relacionadas com Saúde/educação , Avaliação Educacional/estatística & dados numéricos , Universidades/estatística & dados numéricos , Competência Clínica , Humanos , Estudos Prospectivos , Fatores Socioeconômicos , Estados Unidos
12.
Sci Rep ; 8(1): 7062, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29728636

RESUMO

The emergence of Staphylococcus aureus strains resistant to 'last resort' antibiotics compels the development of new antimicrobials against this important human pathogen. We found that propyl 5-hydroxy-3-methyl-1-phenyl-1H-pyrazole-4-carbodithioate (HMPC) shows bacteriostatic activity against S. aureus (MIC = 4 µg/ml) and rescues Caenorhabditis elegans from S. aureus infection. Whole-genome sequencing of S. aureus mutants resistant to the compound, along with screening of a S. aureus promoter-lux reporter array, were used to explore possible mechanisms of action. All mutants resistant to HMPC acquired missense mutations at distinct codon positions in the global transcriptional regulator mgrA, followed by secondary mutations in the phosphatidylglycerol lysyltransferase fmtC/mprF. The S. aureus promoter-lux array treated with HMPC displayed a luminescence profile that was unique but showed similarity to DNA-damaging agents and/or DNA replication inhibitors. Overall, HMPC is a new anti-staphylococcal compound that appears to act via an unknown mechanism linked to the global transcriptional regulator MgrA.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Antibacterianos/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Genoma Bacteriano , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/metabolismo , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Mutação , Relação Estrutura-Atividade , Sequenciamento Completo do Genoma
13.
Methods Mol Biol ; 378: 125-52, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18605082

RESUMO

Analytical cytometry has significant potential beyond cellular analysis. The inherent capability of flow cytometers to efficiently discriminate between uniformly sized particles based on their intrinsic properties provides the foundation for multiplex bead assays. The technology can be exploited in designing immunoassays, Western blot-like antibody assays, and nucleic acid hybridization assays. This chapter focuses on immunoassay applications. The multiplex bead assays have recently evolved as a new and increasingly popular area for flow cytometry, becoming a good alternative to enzyme-linked immunosorbent assay for efficient evaluation of panels of analytes. This chapter provides detailed information about two bead platforms, the BD Cytometric Bead Array kits and the BD Cytometric Bead Array Flex Set Assays.


Assuntos
Citometria de Fluxo/métodos , Anafilaxia/diagnóstico , Anafilaxia/imunologia , Western Blotting/métodos , Desenho de Equipamento , Citometria de Fluxo/instrumentação , Humanos , Imunoensaio/métodos , Isotipos de Imunoglobulinas/análise , Inflamação/diagnóstico , Inflamação/imunologia , Kit de Reagentes para Diagnóstico
14.
Future Med Chem ; 8(16): 1941-1952, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27652456

RESUMO

AIM: Increasing antimicrobial resistance has compromised the effectiveness of many antibiotics, including those used to treat staphylococcal infections like methicillin-resistant Staphylococcus aureus. The development of combination therapies, where antimicrobial agents are used with compounds that inhibit resistance pathways is a promising strategy. Results/methodology: The Raf kinase inhibitor GW5074 exhibited selective in vitro activity against Gram-positive bacteria, including clinical isolates of S. aureus with a minimum inhibitory concentration (MIC) of 2-8 µg/ml. GW5074 was effective in vivo in the Galleria mellonella infection model. The compound showed synergy with gentamicin by lowering MIC by fourfold, compared with gentamicin MIC alone. CONCLUSION: This work demonstrates the antimicrobial properties of GW5074 and supports further investigation of the kinase inhibitors as antibiotic adjuvants.

15.
J Immunol Methods ; 306(1-2): 183-92, 2005 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-16194545

RESUMO

The hepatitis B virus X protein (HBxAg) is responsible for severe complications of HBV infections including primary hepatocellular carcinoma. A sandwich type ELISA and a flow cytometric microbead assay for quantitative determination of serum levels of Hbx-Ag are introduced. We have previously developed monoclonal antibody families against well-conserved epitopes on HbxAg, characterized by different immunohistochemical and immunoserological techniques. Special selection of the antibody pairs provided highly sensitive and highly specific tools for quantitative immunoassay development. The resulting assays were tested on human sera (208 samples) collected from patients suffering from different clinical forms of HBV infection. The sensitivity range of the sandwich type ELISA was between 4 and 2000 ng/ml as measured on both the recombinant antigen and the sera of chronic hepatitis patients. A further flow cytometric microbead assay was established and tested in parallel with the ELISA. The quantitative results of these two immunoserological techniques were in strong correlation and they were found to be highly specific and sensitive on clinical samples. The HBxAg ELISA technique is applicable for routine clinical laboratory measurements, and our HBxAg microbead technique is recommended for complex multiparametric measurements combined with other markers.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Citometria de Fluxo/métodos , Hepatite B/diagnóstico , Transativadores/sangue , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Humanos , Microesferas , Dados de Sequência Molecular , Sensibilidade e Especificidade , Proteínas Virais Reguladoras e Acessórias
16.
Stud Health Technol Inform ; 107(Pt 1): 346-50, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15360832

RESUMO

This paper describes Kaiser Permanente's (KP) enterprise-wide medical terminology solution, referred to as our Convergent Medical Terminology (CMT). Initially developed to serve the needs of a regional electronic health record, CMT has evolved into a core KP asset, serving as the common terminology across all applications. CMT serves as the definitive source of concept definitions for the organization, provides a consistent structure and access method to all codes used by the organization, and is KP's language of interoperability, with cross-mappings to regional ancillary systems and administrative billing codes. The core of CMT is comprised of SNOMED CT, laboratory LOINC, and First DataBank drug terminology. These are integrated into a single poly-hierarchically structured knowledge base. Cross map sets provide bi-directional translations between CMT and ancillary applications and administrative billing codes. Context sets provide subsets of CMT for use in specific contexts. Our experience with CMT has lead us to conclude that a successful terminology solution requires that: (1) usability considerations are an organizational priority; (2) "interface" terminology is differentiated from "reference" terminology; (3) it be easy for clinicians to find the concepts they need; (4) the immediate value of coded data be apparent to clinician user; (5) there be a well defined approach to terminology extensions. Over the past several years, there has been substantial progress made in the domain coverage and standardization of medical terminology. KP has learned to exploit that terminology in ways that are clinician-acceptable and that provide powerful options for data analysis and reporting.


Assuntos
Sistemas Pré-Pagos de Saúde , Vocabulário Controlado , Logical Observation Identifiers Names and Codes , Systematized Nomenclature of Medicine , Terminologia como Assunto , Estados Unidos
18.
Lab Invest ; 84(10): 1387-98, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15311213

RESUMO

The multiple cellular and soluble elements of the immune system respond in a coordinated way, orchestrated by cytokines, to preserve the integrity of the organism. In this study, we describe a new and unique whole blood method that, with minimal sample manipulation, allows an overall evaluation of immune responses by simultaneously measuring cell activation and cytokine secretion. The identification of cells actively secreting cytokines is based on the stabilization of tumor necrosis factor alpha (TNFalpha) at the cell surface through the use of a specific inhibitor of the TNFalpha-converting enzyme. This inhibitor does not affect the release of cytokines other than TNFalpha and makes it possible to assess, in the same measurement, the phenotype of TNFalpha(+)-secreting cells and quantify multiple secreted cytokines by using a specific and highly sensitive flow cytometry-based bead immunoassay. Upon stimulation of normal peripheral blood samples with either phorbol 12-myristate 13 acetate (PMA) plus ionomycin or lipopolysaccharide (LPS), both the number of TNFalpha+ cells and the amount of secreted cytokines progressively increased, the former becoming detectable first. After stimulation for 3 h with PMA plus ionomycin, cellular responses were associated with surface TNFalpha expression on the majority of CD3+ T cells and secretion of Th1-associated cytokines: interferon gamma, interleukin (IL)-2, and to a lesser extent IL4. In turn, stimulation with LPS induced a response mainly by inflammatory cells. After 4 h of LPS-stimulation, the majority of CD14+ monocytes showed surface TNFalpha expression; in parallel, high amounts of soluble IL1beta, IL6, and IL8 became detectable. Likewise, stimulation of blood samples with cytomegalovirus (CMV) lysates induced viral-specific immune responses detectable in seropositive but not seronegative volunteers; such responses were associated with the detection of increased numbers of TNFalpha+ monocytes, TNFalpha+/CD8+ T cells and TNFalpha+/CD8- T lymphocytes in association with an increased secretion of IFNgamma, IL6 and TNFalpha.


Assuntos
Citocinas/biossíntese , Citometria de Fluxo/métodos , Leucócitos Mononucleares/citologia , Subpopulações de Linfócitos T/citologia , Acetato de Tetradecanoilforbol/análogos & derivados , Adulto , Citometria de Fluxo/instrumentação , Humanos , Ionomicina/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Sensibilidade e Especificidade , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
19.
Clin Immunol ; 110(3): 252-66, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15047203

RESUMO

The introduction of flow cytometric bead-based technology has added a new approach for investigators to simultaneously measure multiple analytes in biological and environmental samples. This new technology allows for (1) evaluation of multiple analytes in a single sample; (2) utilization of minimal sample volumes to glean data; (3) reproducibility and results comparative with previous experiments; (4) direct comparison with existing assays; and (5) a more rapid evaluation of multiple samples in a single platform. The cytometric bead array (CBA) system enables simultaneous measurement of multiple analytes in sample volumes too small for traditional immunoassays. Results have been presented for the analysis of a variety of human cytokines. In addition, the technology allows for the design and creation of assays to measure a variety of analytes including inflammatory mediators, chemokines, immunoglobulin isotypes, intracellular signaling molecules, apoptotic mediators, adhesion molecules, and antibodies. New initiatives put forward by the Human Genome Project and the FDA require the development and use of assays for the rapid simultaneous quantitation of multiple analytes. The CBA technology provides the ability to quantify multiple proteins within a given sample, with precision and consistency.


Assuntos
Citometria de Fluxo/métodos , Imunoensaio/métodos , Anafilatoxinas/análise , Anafilatoxinas/imunologia , Animais , Anticorpos/análise , Anticorpos/imunologia , Apoptose/imunologia , Caspases/análise , Caspases/imunologia , Citocinas/análise , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Microesferas , Fosfotransferases/análise , Fosfotransferases/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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