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1.
Int J Anal Chem ; 2013: 628397, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23710181

RESUMO

Mercury has been determined in Ayurvedic dietary supplements (Trifala, Trifala Guggulu, Turmeric, Mahasudarshan, Yograj, Shatawari, Hingwastika, Shatavari, and Shilajit) by inductively coupled plasma-mass spectrometry (ICP-MS) and direct mercury analysis using the Hydra-C direct mercury analyzer (Teledyne Leeman Labs Hudson, NH, USA). Similar results were obtained from the two methods, but the direct mercury analysis method was much faster and safer and required no microwave digestion (unlike ICP-MS). Levels of mercury ranged from 0.002 to 56 µ g/g in samples of dietary supplements. Standard reference materials Ephedra 3240 and tomato leaves that were from the National Institute of Standard and Technology (NIST) and dogfish liver (DOLT3) that was from the Canadian Research Council were analyzed using Hydra-C method. Average mercury recoveries were 102% (RSD% 0.0018), 100% (RSD% 0.0009), and 101% (RSD% 0.0729), respectively. Hydra-C method Limit Of Quantitation was 0.5 ng.

2.
Anal Chem ; 83(21): 8300-7, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21936491

RESUMO

Iodine is an essential micronutrient especially important in the neurodevelopment of infants. Spot samples of urinary iodine (UI) are used as an epidemiologic index of adult iodine nutrition. Individual infant iodine nutrition is of vital importance, but infant urine is difficult to collect, much less a 24 h sample. Monitoring the intake provides a pragmatic solution for determining infant iodine nutrition. Because of the high solids content of milk and the possible existence of iodine in an organically bound form, sample digestion is obligatory. The U.S. Food and Drug Administration, for example, uses wet ashing by HClO(4); special precautions and fume hoods are required. We present a method of Fenton digestion of human and bovine milk samples and infant formula. No specialized equipment or hazardous reagents are used; measurement is made by isotope dilution inductively coupled plasma mass spectrometry. In Fenton digestion, Fe(II) and H(2)O(2) oxidizes the sample. In an interlaboratory study, excellent agreement (r(2) = 0.9934) was observed with results obtained by HClO(4) digestion and Sandel-Kolthoff kinetic colorimetry. Average recoveries of iodide, triiodothyronine, and thyroxine ranged between 100% and 101%. Following digestion, iodine was found to exist entirely as iodide. Control of pH is imperative if loss cannot be corrected for by isotope dilution. Loss was below 20% for all samples when the pH was between 2.25 and 2.5.


Assuntos
Mama/química , Peróxido de Hidrogênio/química , Fórmulas Infantis/química , Iodo/análise , Ferro/química , Espectrometria de Massas , Leite/química , Adulto , Animais , Bovinos , Feminino , Humanos , Lactente , Iodo/sangue , Iodo/urina
3.
Eur J Haematol ; 79(5): 371-81, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17916084

RESUMO

OBJECTIVES: To elucidate long-term effects of idiotype (Id) vaccination on Id-specific T cells of multiple myeloma (MM) patients and compare Id-specific T-cell responses of peripheral blood with those of bone marrow (BM). MATERIALS AND METHODS: Id-specific T-cell responses of peripheral blood mononuclear cells (PBMC) were compared with those of BM mononuclear cells (BMMC) in 10 MM patients vaccinated with the Id protein at a median time of 41 months since the last immunization. The PBMC responses at late follow-up were also compared with those during active immunization. The responses were assessed by a proliferation assay, enzyme-linked immunospot (ELISPOT) (gamma-interferon), cytometric bead array (CBA) for secreted cytokines and quantitative real-time polymerase chain reaction (QRT-PCR) for cytokine gene expression. RESULTS: At the late testing time, an Id-specific response was detected in PBMC of five patients (ELISPOT, CBA, QRT-PCR) and in BMMC of four patients (CBA, QRT-PCR). A response in both compartments was noted only in three patients. The cytokines gene profile was consistent with a predominance of Th(2) cells [interleukin (IL)-4, IL-5, IL-10]. Comparison of the Id-specific responses of PBMC during active immunization with those at the late follow-up showed that the frequency and magnitude of the responses had decreased significantly by time (proliferation/ELISPOT) (P < 0.02) and shifted at the gene level from a Th(1) to a Th(2) profile (P < 0.05). CONCLUSION: Id-specific T-cells may decline overtime and shift toward a Th(2) response and may be found at a similar frequency of patients in blood and BM.


Assuntos
Medula Óssea/imunologia , Vacinas Anticâncer/uso terapêutico , Imunoglobulina G/administração & dosagem , Idiótipos de Imunoglobulinas/administração & dosagem , Leucócitos Mononucleares/imunologia , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/terapia , Linfócitos T/imunologia , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Fragmentos Fab das Imunoglobulinas/metabolismo , Masculino , Pessoa de Meia-Idade , Fenótipo , Reação em Cadeia da Polimerase , Receptores Imunológicos/metabolismo , Fatores de Tempo
4.
Clin Cancer Res ; 13(12): 3536-44, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17575216

RESUMO

PURPOSE: Erythropoietin (EPO) and EPO receptor (EPO-R) expression have been reported in solid tumors and are claimed to regulate tumor growth; however, no data have been published on this issue in B-cell malignancies or normal lymphoid cells. This report describes genomic/protein EPO-R expression and in vitro effects of recombinant human EPO (epoetin) in B-cell chronic lymphocytic leukemia (B-CLL), mantle-cell lymphoma (MCL), and multiple myeloma (MM). EXPERIMENTAL DESIGN: Blood samples were obtained from patients with B-CLL, MCL, and healthy volunteers, and bone marrow was obtained from MM patients. EPO-R mRNA was detected by reverse transcription-PCR. EPO-R surface expression was investigated by flow cytometry using digoxigenin-labeled epoetin and polyclonal rabbit anti-EPO-R antibody for intracellular receptor. Tumor cell stimulation was determined in vitro using [(3)H]thymidine incorporation and CD69 expression after exposure to epoetin alpha or beta or darbepoetin alpha. RESULTS: EPO-R mRNA was detected in mononuclear cells from 32 of 41 (78%) B-CLL and 5 of 7 (71%) MCL patients, and 21 of 21 (100%) MM samples. Expression was also detected in highly purified T cells from six of eight B-CLL patients, four of four MM patients, and normal donor B and T cells. Surface EPO-R protein was not detected. Intracellular EPO-R staining with anti-EPO-R antibodies was unspecific. No tumor-stimulatory effect was observed with high epoetin concentrations. CONCLUSIONS: EPO-R gene is frequently expressed in lymphoid malignancies and normal B and T cells. However, there was no surface protein expression and no epoetin-induced in vitro stimulation of tumor B cells, indicating that epoetin therapy in vivo is likely to be safe in patients with lymphoid malignancies.


Assuntos
Eritropoetina/metabolismo , Leucemia de Células B/metabolismo , Linfoma de Célula do Manto/metabolismo , Mieloma Múltiplo/metabolismo , Receptores da Eritropoetina/biossíntese , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/biossíntese , Antígenos de Diferenciação de Linfócitos T/biossíntese , Feminino , Citometria de Fluxo , Expressão Gênica , Humanos , Técnicas In Vitro , Lectinas Tipo C , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Clin Cancer Res ; 13(5): 1503-10, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17332295

RESUMO

PURPOSE AND EXPERIMENTAL DESIGN: Twenty-eight patients with immunoglobulin G myeloma stages I to II were immunized i.d. over 110 weeks with autologous M protein combined with interleukin-12 (IL-12; n = 15) or with IL-12 and granulocyte macrophage colony-stimulating factor (GM-CSF; n = 13). Idiotype-specific T-cell responses were assessed by [(3)H]thymidine incorporation, enzyme-linked immunospot assay, and delayed-type hypersensitivity reaction. RESULTS: Based on these three assays, idiotype-specific immune responses were noted in 5 of 15 (33%) patients in the IL-12 group and in 11 of 13 (85%) patients in the GM-CSF/IL-12 group (P < 0.01). Immune response was seen only in patients with M-component concentration of <50 g/L. Three of 16 (19%) responders showed a gradually increasing idiotype-specific T-cell response, whereas 11 of 16 (69%) patients showed initial response, which then disappeared rapidly; the latter pattern was frequently associated with subsequent progressive disease. Immune nonresponse was associated with an increase in the numbers of CD4(+)/CD25(+) cells (regulatory T cells), which was absent in responding patients. Median time to progression for immune responders (n = 16) was 108 weeks compared with 26 weeks for nonresponders (n = 12; P = 0.03). CONCLUSIONS: These results indicate that idiotype immunization of myeloma patients with GM-CSF and IL-12 may induce specific T-cell response more frequently than with IL-12 alone and that immune response may correlate with time to progression and nonresponse with increased numbers of regulatory T cells.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Idiótipos de Imunoglobulinas/uso terapêutico , Imunoterapia/métodos , Mieloma Múltiplo/tratamento farmacológico , Idoso , Vacinas Anticâncer/imunologia , Ensaio de Imunoadsorção Enzimática , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Humanos , Idiótipos de Imunoglobulinas/imunologia , Interleucina-12/imunologia , Interleucina-12/uso terapêutico , Pessoa de Meia-Idade , Mieloma Múltiplo/imunologia , Proteínas do Mieloma/imunologia , Linfócitos T Reguladores/imunologia , Fatores de Tempo
6.
Haematologica ; 92(1): 110-4, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17229643

RESUMO

Anti-idiotypic T cells were analyzed in myeloma patients (n=18) vaccinated with idiotypic protein together with the adjuvant cytokines granulocyte-macrophage colony-stimulating factor (GM-CSF) and/or interleukin-12 (IL-12). In the group given IL-12/GM-CSF, 78% developed idiotype specific T cells as compared to 22% in the group given only IL-12 (proliferation/ELISPOT assays) (p<0.05). The percentage of immune-responding patients increased when quantitative real time polymerase chain reaction assays for cytokines were included. A predominance of a Th1 (IFN-gamma/TNF-alpha) immune response was noted in the IL-12 group while a Th2 (IL-5) response prevailed in the IL-12/GM-CSF group (p=0.053). Application of multiple read-out systems improved the characterization of the immune response.


Assuntos
Citocinas/metabolismo , Hematologia/instrumentação , Idiótipos de Imunoglobulinas/química , Mieloma Múltiplo/metabolismo , Linfócitos T/metabolismo , Idoso , Idoso de 80 Anos ou mais , Vacinas Anticâncer/química , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Hematologia/métodos , Humanos , Interferon gama/metabolismo , Interleucina-12/uso terapêutico , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Th1 , Fator de Necrose Tumoral alfa/metabolismo
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