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1.
ACS Chem Neurosci ; 13(17): 2658-2665, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-35946788

RESUMO

Multiple sclerosis (MS) is an inflammatory disease characterized by damage to the myelin sheath surrounding axons in the central nervous system. While the exact mechanism of this destruction is unknown, excess nitric oxide (NO) and adenosine triphosphate (ATP) have been measured in tissues and fluids obtained from people with MS. Here, incubation of interferon-beta (IFN-ß), an MS drug with an unknown mechanism of action, with red blood cells (RBCs) obtained from people with MS provide evidence of a potential hypermetabolic state in the MS RBC that is decreased with IFN-ß intervention. Specifically, binding of all three components of an albumin/C-peptide/Zn2+ complex to MS RBCs was significantly increased in comparison to control RBCs. For example, the binding of C-peptide to MS RBCs was significantly increased (3.4 ± 0.1 nM) compared to control RBCs (1.6 ± 0.2 nM). However, C-peptide binding to MS RBCs was reduced to a value (1.6 ± 0.3 nM) statistically equal to that of control RBCs in the presence of 2 nM IFN-ß. Similar trends were measured for albumin and Zn2+ binding to RBCs when in the presence of IFN-ß. RBC function was also affected by incubation of cells with IFN-ß. Specifically, RBC-derived ATP and measurable membrane GLUT1 were both significantly decreased (56 and 24%, respectively) in the presence of IFN-ß. Collectively, our results suggest that IFN-ß inhibits albumin binding to the RBC, thereby reducing its ability to deliver ligands such as C-peptide and Zn2+ to the cell and normalizing the basal hypermetabolic state.


Assuntos
Interferon beta , Esclerose Múltipla , Trifosfato de Adenosina/metabolismo , Albuminas/metabolismo , Peptídeo C/metabolismo , Eritrócitos/metabolismo , Humanos , Interferon beta/metabolismo , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo
2.
Sci Rep ; 10(1): 17493, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060722

RESUMO

People with type 1 diabetes (T1D) require exogenous administration of insulin, which stimulates the translocation of the GLUT4 glucose transporter to cell membranes. However, most bloodstream cells contain GLUT1 and are not directly affected by insulin. Here, we report that C-peptide, the 31-amino acid peptide secreted in equal amounts with insulin in vivo, is part of a 3-component complex that affects red blood cell (RBC) membranes. Multiple techniques were used to demonstrate saturable and specific C-peptide binding to RBCs when delivered as part of a complex with albumin. Importantly, when the complex also included Zn2+, a significant increase in cell membrane GLUT1 was measured, thus providing a cellular effect similar to insulin, but on a transporter on which insulin has no effect.


Assuntos
Peptídeo C/administração & dosagem , Eritrócitos/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Soroalbumina Bovina/química , Zinco/administração & dosagem , Trifosfato de Adenosina/química , Animais , Transporte Biológico , Bovinos , Membrana Celular/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Regulação da Expressão Gênica , Glucose/metabolismo , Humanos , Insulina/metabolismo
3.
Mol Imaging Biol ; 18(2): 232-42, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26335283

RESUMO

PURPOSE: The use of receptor-targeted antibodies conjugated to photosensitizers is actively being explored to enhance treatment efficacy. To facilitate clinical testing, we evaluated cetuximab conjugated to IRDye700DX (IR700) in cynomolgus macaques. PROCEDURES: Total IR700 and intact cetuximab-IR700 were measured in 51 tissues at 2 and 14 days after intravenous injection of 40 and 80 mg/kg cetuximab-IR700, respectively, and compared with an unlabeled cetuximab-dosed control group (two each per sex per time point per group). RESULTS: The IR700 retrieved from all tissues at 2 and 14 days after dosing was estimated at 34.9 ± 1.8 and 2.53 ± 0.67% of the total dose, respectively. The tissues with the highest levels of intact cetuximab-IR700 at 2 days after dosing were the blood, lung, and skin. Formalin-fixed paraffin-embedded tissue sections at 2 days after dosing showed the highest IR700 signals in the axillary lymph node, mammary gland, and gall bladder. CONCLUSIONS: Both IR700 and intact cetuximab-IR700 biodistributions were consistent with known epidermal growth factor receptor (EGFR) expression, and changes between 2 and 14 days were consistent with rapid metabolism and excretion of the cetuximab-IR700.


Assuntos
Cetuximab/administração & dosagem , Cetuximab/metabolismo , Corantes/metabolismo , Imagem Molecular/métodos , Animais , Feminino , Fluorescência , Injeções Intravenosas , Macaca fascicularis , Masculino , Distribuição Tecidual
4.
Gene Ther ; 21(10): 897-902, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25056609

RESUMO

Detection of prostate-specific antigen (PSA) as a screening strategy for prostate cancer is limited by the inability of the PSA test to differentiate between malignant cancer and benign hyperplasia. Here, we report the use of a cancer-specific promoter, inhibition of differentiation-1 (Id1), to drive a dual-reporter system (Ad5/3-Id1-SEAP-Id1-mCherry) designed for detection of prostate cancer using a blood-based reporter-secreted embryonic alkaline phosphatase (SEAP) and tumor visualization using a fluorescent reporter protein, mCherry. In human prostate tumors, Id1 levels are correlated with increased Gleason grade and disease progression. To evaluate the performance of the dual-reporter system, a prostate cell panel with varying aggressive phenotypes was tested. Following infection with the Ad5/3-Id1-SEAP-Id1-mCherry vector, expression of the SEAP and mCherry reporters was shown to increase with increasing levels of cellular Id1. No correlation was observed between Id1 and PSA. To evaluate in vivo performance, flank tumors were grown in athymic male mice using three prostate cancer cell lines. Following intra-tumoral injection of the vector, tumors formed by cells with high Id1 had the greatest reporter expression. Interestingly, tumors with the lowest levels of Id1 and reporter expression produced the greatest amounts of PSA. These data support the use of Ad5/3-Id1-SEAP-Id1-mCherry as a predictor of prostate cancer malignancy and as a strategy for tumor localization.


Assuntos
Fosfatase Alcalina/metabolismo , Diagnóstico por Imagem/métodos , Vetores Genéticos/administração & dosagem , Proteína 1 Inibidora de Diferenciação/metabolismo , Neoplasias da Próstata/diagnóstico , Fosfatase Alcalina/genética , Animais , Linhagem Celular Tumoral , Dependovirus/genética , Progressão da Doença , Genes Reporter , Humanos , Proteína 1 Inibidora de Diferenciação/genética , Proteínas Luminescentes/metabolismo , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Antígeno Prostático Específico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteína Vermelha Fluorescente
5.
Virus Res ; 176(1-2): 259-64, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23845301

RESUMO

The role played by seed transmission in the evolution and epidemiology of viral crop pathogens remains unclear. We determined the seed infection and vertical transmission rates of zucchini yellow mosaic virus (ZYMV), in addition to undertaking Illumina sequencing of nine vertically transmitted ZYMV populations. We previously determined the seed-to-seedling transmission rate of ZYMV in Cucurbita pepo ssp. texana (a wild gourd) to be 1.6%, and herein observed a similar rate (1.8%) in the subsequent generation. We also observed that the seed infection rate is substantially higher (21.9%) than the seed-to-seedling transmission rate, suggesting that a major population bottleneck occurs during seed germination and seedling growth. In contrast, that two thirds of the variants present in the horizontally transmitted inoculant population were also present in the vertically transmitted populations implies that the bottleneck at vertical transmission may not be particularly severe. Strikingly, all of the vertically infected plants were symptomless in contrast to those infected horizontally, suggesting that vertical infection may be cryptic. Although no known virulence determining mutations were observed in the vertically infected samples, the 5' untranslated region was highly variable, with at least 26 different major haplotypes in this region compared to the two major haplotypes observed in the horizontally transmitted population. That the regions necessary for vector transmission are retained in the vertically infected populations, combined with the cryptic nature of vertical infection, suggests that seed transmission may be a significant contributor to the spread of ZYMV.


Assuntos
Cucurbita/virologia , Transmissão Vertical de Doenças Infecciosas , Doenças das Plantas/virologia , Potyvirus/isolamento & purificação , Sementes/virologia , Viroses/transmissão , Viroses/virologia , Regiões 5' não Traduzidas , Transmissão de Doença Infecciosa , Variação Genética , Dados de Sequência Molecular , RNA Viral/genética , Análise de Sequência de DNA
6.
Cancer Gene Ther ; 19(8): 545-52, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22653385

RESUMO

One of the major limitations of cancer gene therapy using recombinant human adenovirus (Ad) is rapid Ad inactivation from systemic delivery. To eliminate this, biotin-coated ultrasound contrast agents, or microbubbles (MBs), were streptavidin-coupled with biotinylated antibodies to three distinct tumor vasculature-associated receptors (α(V)ß(3) integrin, P-selectin and vascular endothelial growth factor receptor-2) for systemic targeting of a previously generated vector Ad5/3-Id1-SEAP-Id1-mCherry. This cancer-specific, dual-reporter vector was loaded in the targeted MBs and confirmed by confocal microscopy. MB loading capacity was estimated by functional assays as 4.72 ± 0.2 plaque forming unit (PFU) per MB. Non-loaded (free) Ad particles were effectively inactivated by treatment with human complement. The Ad-loaded, targeted-MBs were injected systemically in mice bearing MDA-MB-231 tumors (Grp 1) and compared with two control groups: Ad-loaded, non-targeted MBs (Grp 2) and free Ad (Grp 3) administered under the same conditions. Two days after administration the blood levels of secreted embryonic alkaline phosphatase (SEAP) reporter in Grp 1 mice (16.1 ng ml(-1) ± 2.5) were significantly higher (P<0.05) than those in Grp 2 (9.75 ng ml(-1) ± 1.5) or Grp 3 (4.26 ng ml(-1) ± 2.5) animals. The targeted Ad delivery was also confirmed by fluorescence imaging. Thus, Ad delivery by targeted MBs holds potential as a safe and effective system for systemic Ad delivery for the purpose of cancer screening.


Assuntos
Neoplasias da Mama , Técnicas de Transferência de Genes , Terapia Genética , Microbolhas/uso terapêutico , Adenoviridae , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos , Humanos , Integrina alfa5/genética , Integrina alfa5/uso terapêutico , Camundongos , Camundongos Nus , Selectina-P/genética , Selectina-P/uso terapêutico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/uso terapêutico
7.
J Anim Physiol Anim Nutr (Berl) ; 93(4): 447-55, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18492029

RESUMO

An experiment was conducted to analytically define several novel fish substrates and determine the effects of feeding diets containing these substrates on total tract nutrient digestibilities and on immune status of senior dogs. The control diet contained poultry by-product meal while test diets contained 20% milt meal (MM), pink salmon hydrolysate (PSH) and white fish meal (WFM) added at the expense of poultry by-product meal. Concentrations of lymphocytes positive for CD3, CD4, CD8 and CD21 cell-surface markers and immunoglobulin concentrations were measured. Gene expression of cytokines tumour necrosis factor (TNF)-, interleukin (IL)-6, interferon (IFN)-, IL-10 and transforming growth factor (TGF)-ß was determined by quantitative real-time polymerase chain reaction. Major compositional differences were noted among fish substrates but apparent nutrient digestibility coefficients and immune indices were not affected by treatment. Fish protein substrates were found to be effective substitutes for poultry by-product meal, providing diets of high nutritive value for senior dogs.


Assuntos
Envelhecimento/fisiologia , Ração Animal/análise , Cães , Proteínas de Peixes/metabolismo , Produtos Avícolas/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Digestão , Ingestão de Alimentos , Fezes , Feminino , Proteínas de Peixes/análise , Masculino , Valor Nutritivo
8.
Technol Cancer Res Treat ; 7(1): 61-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18198926

RESUMO

Optical fluorescent technology has the potential to deliver real time imaging of cancer into the operating room and the clinic. To determine the efficacy of fluorescently labeled anti-vascular endothelial growth factor (VEGF) antibody to be used as a cancer specific optical contrast agent to guide surgical resections, we evaluated the sensitivity and specificity of this agent to detect microscopic residual disease in a preclinical model of head and neck squamous cell carcinoma (HNSCC). Using a flank murine model, mice were xenografted with SCC-1 tumor cells and injected with anti-VEGF antibody (bevacizumab) conjugated to an optically active fluorophore (Cy5.5). Tumors underwent sub-total resections and were assessed for the presence of residual disease by fluorescent stereomicroscopy. Expected positive and negative biopsies were taken according to the presence or absence of fluorescence, respectively. Histology was used to confirm the presence or absence of disease. Biopsies taken from areas of fluorescence within the wound bed (n=18) were found to be histologically malignant in all but one biopsy. Samples taken from a non-fluorescing tumor bed (n=15) were found to be histologically benign in 11 of 15. These findings correlated with a sensitivity and specificity of 80.9% and 91.7%, respectively. This data supports previous data presented by this group and supports further investigation of fluorescently labeled anti-tumor antibodies to detect disease in the surgical setting.


Assuntos
Anticorpos Monoclonais , Carbocianinas , Neoplasias de Cabeça e Pescoço/diagnóstico , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Anticorpos Monoclonais Humanizados , Bevacizumab , Humanos , Masculino , Camundongos , Camundongos SCID , Transplante de Neoplasias , Transplante Heterólogo
9.
Clin Exp Metastasis ; 24(5): 389-401, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17541709

RESUMO

This study sought to determine if weekly X-ray exposure affected breast cancer cell metastasis to bone and to also evaluate the use of bioluminescent imaging (BLI) and microSPECT for detection of metastatic bone lesions. Five week old nude mice were randomly assigned to the CT exposed (n = 7) and no CT exposure (n = 6) treatment groups. Mice received an intracardiac injection of MDA-MB-435 human breast cancer cells transduced with luciferase, or a sham injection (saline). The CT exposed group of mice received CT irradiation once a week for 5 weeks. All mice underwent weekly BLI and select mice received Tc-99m-MDP followed by microSPECT imaging after 5 weeks. Pathological evaluation and histomorphometry were used to assess the affect of CT X-rays on bone metastasis and to evaluate BLI. BLI results found no significant difference in metastasis between animals that received CT and those that did not (P > 0.05); however, histomorphometry of the knee joints revealed a significant increase (P = 0.029) in tumor area of the leg bones in mice that received CT exposure (60% +/- 7%) compared to animals that did not receive CT scans (33% +/- 8%). Compared to histological analysis, BLI of the leg and spine was determined to have excellent sensitivity (100%), good specificity (80-90%) and accuracy (90-96%), a positive predictive value of 81-93% and a 100% negative predictive value. Thus, multi-modality imaging techniques can be very useful for monitoring bone metastasis, however microCT X-rays should be used judiciously in order to limit irradiation that may stimulate increased metastasis to specific regions of the skeleton. MicroSPECT imaging did not detect metastatic lesions in the legs of these young nude mice.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Mamárias Experimentais/patologia , Animais , Neoplasias Ósseas/secundário , Osso e Ossos/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Luminescência , Camundongos , Camundongos Nus , Transplante de Neoplasias , Especificidade de Órgãos , Valor Preditivo dos Testes , Distribuição Aleatória , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/efeitos adversos , Tomografia Computadorizada por Raios X/métodos , Transplante Heterólogo
10.
J Anim Sci ; 84(6): 1403-14, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16699097

RESUMO

This experiment was designed to evaluate the effects of selected soybean (SB) processing byproducts (gums, oil, soapstock, weeds/trash) when added back to soybean meal (SBM) during processing on the resulting nutrient composition, protein quality, nutrient digestibility by swine, and true metabolizable energy (TMEn) content and standardized AA digestibility by poultry. To measure ileal DM and nutrient digestibility, pigs were surgically fitted with a T-cannula in the distal ileum. The concentration of TMEn and the standardized AA digestibility by poultry were determined using the precision fed cecectomized rooster assay. Treatments in the swine experiment included SBM with no by-products; SBM with 1% gum; SBM with 3% gum; SBM with 0.5% soapstock; SBM with 1.5% soapstock; SBM with 2% weeds/trash; SBM with a combination of 3% gum, 1.5% soapstock, and 2% weeds/trash; SBM with 5.4% soybean oil; and roasted SB. A 10 x 10 Latin square design was utilized. The experiment was conducted at the University of Illinois, Urbana-Champaign, and at The Ohio State University, Columbus. In the swine experiment, apparent ileal DM, OM, CP, and AA digestibilities were reduced (P < 0.05) when pigs consumed the combination by-product diet compared with the diet containing no by-products. Apparent ileal digestibilities of DM, CP, and total essential, total nonessential, and total AA were lower (P < 0.05) for any diet containing by-products compared with the diet with no by-products. Apparent ileal digestibilities of DM, OM, CP, and AA were lower (P < 0.05) for the roasted SB-compared with the SB oil-containing diet. In the rooster experiment, TMEn values were greater (P < 0.05) for roasted SB compared with SBM with no by-products and increased linearly as the addition of soapstock increased. Individual, total essential, total nonessential, and total AA digestibilities were lower (P < 0.05) for roosters fed roasted SB versus SBM devoid of by-products. Gums, soapstock, and weeds/trash reduce the nutritive value of the resultant meal when they are added back during processing.


Assuntos
Ração Animal/análise , Galinhas/metabolismo , Dieta , Digestão/fisiologia , Glycine max/metabolismo , Óleo de Soja/metabolismo , Suínos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Masculino , Óleo de Soja/administração & dosagem , Óleo de Soja/química , Glycine max/química
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