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1.
Food Chem ; 320: 126567, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32203830

RESUMO

Deliberate chemical contamination of food powders has become a major food safety concern worldwide. This study used Raman imaging and FT-IR spectroscopy to detect Sudan Red and white turmeric adulteration in turmeric powder. While Sudan Red Raman spectral peaks were identifiable in turmeric-Sudan Red samples, Sudan Red false positive detection was observed in binary Raman images, limiting effective quantitative detection. In addition, white turmeric Raman spectral peaks were unidentifiable in turmeric-white turmeric mixtures. However, IR spectra of turmeric-Sudan Red and turmeric-white turmeric samples provided discrete identifier peaks for both the adulterants. Partial least squares regression models were developed using IR spectra for each mixture type. The models estimated Sudan Red and white turmeric concentrations with correlation coefficients of 0.97 and 0.95, respectively. Priority should be given to developing an IR imaging system and incorporating it with Raman system to simultaneously measure of food samples for detection of adulterants.


Assuntos
Compostos Azo/análise , Curcuma/química , Contaminação de Alimentos/análise , Preparações de Plantas/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Pós/química
2.
Drug Test Anal ; 11(2): 200-207, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30110719

RESUMO

Cobaltous ions (Co2+ ) stabilize HIFα, increase endogenous erythropoietin (EPO) production, and may, therefore, be used as a performance-enhancing substance. To date, the dosage necessary to stimulate erythropoiesis is unknown. The aim of this study was, therefore, to determine the minimum dosage necessary to increase erythropoietic processes. In a first double-blind placebo-controlled study (n = 5), single oral Co2+ dosages of 5 mg (n = 6) and 10 mg (n = 7) were administered to healthy young men. Cubital venous blood and urine samples were collected before and up to 24 hours after Co2+ administration. In a second study, the same daily Co2+ dosages were administered for five days (placebo: n = 5, 5 mg: n = 9, 10 mg: n = 7). Blood and urine samples were taken the day before administration and at day 3 and day 5. Plasma [EPO] was elevated by 20.5 ± 16.9% at 5 hours after the single 5-mg administration (p < 0.05) and by 52.8 ± 23.5% up to 7 hours following the 10-mg Co2+ administration (p < 0.001). Urine [Co2+ ] transiently increased, with maximum values 3-5 hours after Co2+ ingestion (5 mg: from 0.8 ± 1.1 to 153.6 ± 109.4 ng/mL, 10 mg: from 1.3 ± 1.7 to 338.0 ± 231,5 ng/mL). During the five days of Co2+ application, 5 mg showed a strong tendency to increase [EPO], while the 10-mg application significantly increased [EPO] at day 5 by 27.2 ± 26.4% (p < 0.05) and the immature reticulocyte fraction by 49.9 ± 21.7% (p < 0.01). [Ferritin] was decreased by 12.4 ± 10.4 ng/mL (p < 0.05). An oral Co2+ dosage of 10 mg/day exerts clear erythropoietic effects, and 5 mg/day tended to increase plasma EPO concentration.


Assuntos
Cobalto/administração & dosagem , Cobalto/farmacologia , Eritropoese/efeitos dos fármacos , Adulto , Contagem de Células Sanguíneas/estatística & dados numéricos , Cobalto/farmacocinética , Cobalto/urina , Método Duplo-Cego , Eritropoetina/sangue , Ferritinas/sangue , Humanos , Masculino , Oligoelementos/farmacocinética , Oligoelementos/farmacologia , Oligoelementos/urina
3.
Med Sci Sports Exerc ; 47(9): 1965-78, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25628173

RESUMO

INTRODUCTION: This controlled, nonrandomized, parallel-groups trial investigated the effects on performance, V˙O2 and hemoglobin mass (tHbmass) of four preparatory in-season training interventions: living and training at moderate altitude for 3 and 4 wk (Hi-Hi3, Hi-Hi), living high and training high and low (Hi-HiLo, 4 wk), and living and training at sea level (SL) (Lo-Lo, 4 wk). METHODS: From 61 elite swimmers, 54 met all inclusion criteria and completed time trials over 50- and 400-m crawl (TT50, TT400), and 100 (sprinters) or 200 m (nonsprinters) at best stroke (TT100/TT200). Maximal oxygen uptake (V˙O2max) and HR were measured with an incremental 4 × 200 m test. Training load was estimated using cumulative training impulse method and session RPE. Initial measures (PRE) were repeated immediately (POST) and once weekly on return to SL (PostW1 to PostW4). tHbmass was measured in duplicate at PRE and once weekly during the camp with CO rebreathing. Effects were analyzed using mixed linear modeling. RESULTS: TT100 or TT200 was worse or unchanged immediately at POST, but improved by approximately 3.5% regardless of living or training at SL or altitude after at least 1 wk of SL recovery. Hi-HiLo achieved greater improvement 2 (5.3%) and 4 wk (6.3%) after the camp. Hi-HiLo also improved more in TT400 and TT50 2 (4.2% and 5.2%, respectively) and 4 wk (4.7% and 5.5%) from return. This performance improvement was not linked linearly to changes in V˙O2max or tHbmass. CONCLUSIONS: A well-implemented 3- or 4-wk training camp may impair performance immediately but clearly improves performance even in elite swimmers after a period of SL recovery. Hi-HiLo for 4 wk improves performance in swimming above and beyond altitude and SL controls through complex mechanisms involving altitude living and SL training effects.


Assuntos
Altitude , Desempenho Atlético/fisiologia , Educação Física e Treinamento/métodos , Natação/fisiologia , Adolescente , Suplementos Nutricionais , Feminino , Hemoglobinometria , Humanos , Ferro da Dieta/administração & dosagem , Masculino , Consumo de Oxigênio , Fatores de Tempo , Adulto Jovem
4.
Med Sci Sports Exerc ; 47(2): 419-27, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24977693

RESUMO

INTRODUCTION: Using hemoglobin concentration ([Hb]) to diagnose borderline iron deficiency and monitor the progress of its treatment is difficult because of the confounding effects of plasma volume. Because hemoglobin mass (Hbmass) is not affected by plasma volume, it may be a more sensitive parameter. The aim of this study was to monitor Hbmass, iron storage, and maximal oxygen consumption (V˙O2max) during and after oral iron therapy in subjects with severe and moderate iron deficiency. METHODS: Three groups of female recreational athletes were monitored for at least 22 wk, as follows: 1) severe iron deficiency group (SID) (n = 8; ferritin, ≤12 ng·mL), 2) moderate iron deficiency group (MID) (n = 14; ferritin, ≤25 ng·mL), and 3) control group (n = 8; ferritin, >25 ng·mL). Hbmass and iron status were determined before, during, and up to 12 wk after at least 10 wk of oral iron supplementation. In total, five V˙O2max tests were performed before, during, and after the supplementation period. RESULTS: Hbmass increased markedly in the SID group (15.6% ± 11.0%, P < 0.001) and slightly in the MID group (2.2% ± 3.7%, P < 0.05) by the end of the supplementation period and remained at this level for the following 12 wk. [Hb] and Hbmass were similarly affected, but Hbmass was more closely related to mean corpuscular volume and mean corpuscular hemoglobin than [Hb]. The SID group incorporated 534 ± 127 mg of iron into ferritin and hemoglobin, whereas the MID group incorporated 282 ± 68 mg of iron. V˙O2max increased only in the SID group by 0.20 ± 0.18 L·min (P < 0.05) and was closely related to Hbmass (P < 0.01). CONCLUSIONS: Hbmass is a sensitive tool for monitoring recovery from iron deficiency anemia and assessing the effectiveness of iron supplementation in individuals with severe or moderate iron deficiency.


Assuntos
Anemia Ferropriva/sangue , Anemia Ferropriva/tratamento farmacológico , Hemoglobinometria/métodos , Hemoglobinas/análise , Administração Oral , Atletas , Suplementos Nutricionais , Feminino , Humanos , Ferro/administração & dosagem , Ferro/sangue , Consumo de Oxigênio
5.
Z Naturforsch C J Biosci ; 59(11-12): 769-76, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15666532

RESUMO

Methanolic leaf extracts of Erythroxylum australe F. Muell. produced eight O-conjugated flavonoids. Six of the flavonoid aglycones were dihydroisoflavones (all dihydro-orobol derivatives), one a flavanone, eriodictyol, and one a flavonol, quercetin. The major glycosides of the flavonoids included mono-glucosyl-rhamnosyls and dirhamnosyl-glucosides with either 3, 5, 7 or 3', 4' linkage or a combination thereof The array of flavonoids present in E. australe suggests kinship to E. ulei and linkage to the four cultivated alkaloid-bearing Erythroxylum, especially the ancestral E. coca var. coca. Because of the uniqueness of the flavonoids present in leaf tissue of E. australe they are unambiguously useful as chemotaxonomic markers for the taxon.


Assuntos
Erythroxylaceae/química , Flavonoides/isolamento & purificação , Folhas de Planta/química , Caules de Planta/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais/análise
6.
J Immunol ; 169(9): 5217-26, 2002 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-12391240

RESUMO

The s.c injection of tumor Ag-derived, MHC class I-binding peptides together with cationic poly-amino acids (e.g., poly-L-arginine; pR) has been shown to protect animals against a challenge with tumor cells expressing the respective peptide(s). Given our only restricted knowledge about immunogenic tumor-associated peptides, we sought to determine whether this pR-based vaccination protocol would also induce protective cancer immunity if large proteins were used instead of peptide epitopes. We found that the intracutaneous administration of the model Ag beta-galactosidase (beta-gal) together with pR (referred to as pR-based protein vaccine; pR-PV) was significantly more potent in protecting mice against the growth of beta-gal-expressing RENCA cells than the protein alone. Coadministration of pR enhanced both the beta-gal-induced specific humoral and CD8 response. The protective effect required CD8(+), but neither CD4(+) T lymphocytes nor beta-gal-specific Abs. beta-Gal priming of protective CD8(+) T lymphocytes was found to be CD4(+) T cell-independent, to take place within the draining lymph nodes, and to be accomplished by day 5 after vaccination. Ablation of the injection sites as early as 1.5 h after pR-PV administration still led to protection in a large proportion of the animals, indicating that certain protein Ags administered intradermally in the context of polycations are quickly transported to the draining nodes, where they induce molecular and cellular events resulting in the helper-independent priming and expansion of Tc1 cells. However, optimal protection required the prolonged presence of the injection site, suggesting that pR-PV injection facilitates the formation of a cutaneous depot of Ag-charged cells capable of migration and T cell activation.


Assuntos
Cátions/imunologia , Peptídeos/imunologia , Poliaminas/imunologia , Vacinas/imunologia , beta-Galactosidase/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Antineoplásicos/administração & dosagem , Antineoplásicos/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Cátions/administração & dosagem , Células Clonais , Citotoxicidade Imunológica , Epitopos de Linfócito T/imunologia , Inibidores do Crescimento/administração & dosagem , Inibidores do Crescimento/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Injeções Intradérmicas , Injeções Subcutâneas , Neoplasias Renais/imunologia , Neoplasias Renais/prevenção & controle , Neoplasias Renais/terapia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Peptídeos/administração & dosagem , Poliaminas/administração & dosagem , Polieletrólitos , Células Tumorais Cultivadas , Vacinas/administração & dosagem , beta-Galactosidase/administração & dosagem
7.
Vaccine ; 20(29-30): 3498-508, 2002 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-12297395

RESUMO

This study describes an entirely synthetic vaccine composed of antigenic peptides (T cell epitopes), oligodeoxynucleotides containing CpG-motifs (CpG-ODN) and poly-L-arginine (pR). CpG-ODN are known to be potent inducers of predominantly type 1-like immune responses, while polycationic amino acids, like pR, facilitate the uptake of antigens into antigen presenting cells (APCs). We demonstrate that the application of peptides and pR/CpG-ODN results in strongly enhanced peptide-specific immune responses as compared to the application of peptides with either of the immunomodulators alone. High numbers of antigen-specific T cells can be observed even after only one injection of the vaccine for a remarkably long period of time (at least 372 days). Furthermore, the potentially harmful systemic release of pro-inflammatory cytokines induced upon injection of CpG-ODN is inhibited. Thus, the combined application of CpG-ODN and pR may represent a novel vaccine strategy in humans.


Assuntos
Adjuvantes Imunológicos/farmacologia , Citocinas/metabolismo , Oligodesoxirribonucleotídeos/farmacologia , Peptídeos/farmacologia , Vacinas Sintéticas/imunologia , Animais , Sinergismo Farmacológico , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Ovalbumina/imunologia , Fragmentos de Peptídeos/imunologia , Eletricidade Estática , Linfócitos T/imunologia , Vacinação
8.
Cancer Res ; 62(5): 1477-80, 2002 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11888923

RESUMO

Vaccines that induce high numbers of sustained T cell responses are urgently needed for the treatment of numerous diseases including cancer. Antigen-presenting cells (APCs), the most important of which are dendritic cells, orchestrate antigen-dependent T cell responses in that they present antigens to T cells in an appropriate environment. Here we present evidence that after vaccination with a simple mixture of the cationic poly-amino acid poly-L-arginine and tumor antigen-derived peptide antigens, large numbers of antigen-specific T cells are induced and APCs mediate the generation of T lymphocytes. We observe that after s.c. injection, MHC class II(+) cells infiltrate injection sites and are loaded with large amounts of antigen in vivo under the influence of poly-L-arginine. Consequently, numerous antigen-charged APCs can be detected in draining lymph nodes of vaccinated animals. Antigen-specific T cell responses induced are systemic and were readily detected more than 4 months after the last vaccination, the latest time point we measured. By contrast, even after repeat injections, we were consistently unable to detect antibody responses against poly-L-arginine, allowing this compound to be used for numerous booster injections. Clinical trials in cancer patients using poly-L-arginine as immunostimulant will be carried out in the near future.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Oxirredutases Intramoleculares/imunologia , Peptídeos/farmacologia , Linfócitos T/imunologia , Animais , Células Apresentadoras de Antígenos/efeitos dos fármacos , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/fisiologia , Movimento Celular/efeitos dos fármacos , Feminino , Antígenos de Histocompatibilidade Classe II/análise , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Vacinação
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