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1.
Shokuhin Eiseigaku Zasshi ; 59(6): 275-281, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30626785

RESUMO

The aluminium (Al) content of Japanese confectionery and foods containing flour was investigated. Some of these items were investigated in previous studies, which examined foods that made use of baking powder containing aluminium potassium sulfate (Alum). Al was detected in 41 of the 123 samples at levels ranging from 0.01 (limit of quantitation) to 0.40 mg/g. The detection rate of Al in almost all confectionery (except Japanese confectionery) was decreased as compared with previous studies. However, the detection rate of Al in Japanese confectionery and foods containing flour was high. For 4 of the 41 samples tested, consuming one serving once a week would result in an Al intake exceeding the PTWI for young children (body weight=16 kg).


Assuntos
Compostos de Alúmen , Alumínio/análise , Sulfato de Cálcio , Farinha/análise , Contaminação de Alimentos/análise , Bicarbonato de Sódio , Amido , Criança , Humanos
2.
Shokuhin Eiseigaku Zasshi ; 58(3): 166-171, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28690308

RESUMO

Stainless steel kitchenware and tableware on sale in Japan were investigated. Surface elemental composition ratios of 172 samples were analyzed by the fluorescence X-ray method. High levels of manganese (9.59-20.03%)were detected in 17 samples. This finding was confirmed by ICP analysis. Next, we conducted migration tests. Samples conformed to the Italian Specific Migration Limits. Moreover, lead and antimony were not detected in these samples, in accordance with the Japanese Food Sanitation Law.


Assuntos
Utensílios de Alimentação e Culinária , Legislação sobre Alimentos/normas , Manganês/análise , Aço Inoxidável/química , Antimônio/análise , Cádmio/análise , Cromo/análise , Ferro/análise , Japão , Chumbo/análise , Níquel/análise , Espectrometria por Raios X
3.
Food Addit Contam Part B Surveill ; 9(3): 185-90, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27092423

RESUMO

Aluminium (Al) levels of 90 food samples were investigated. Nineteen samples contained Al levels exceeding the tolerable weekly intake (TWI) for young children [body weight (bw): 16 kg] when consuming two servings/week. These samples were purchased multiple times at specific intervals and were evaluated for Al levels. Al was detected in 27 of the 90 samples at levels ranging from 0.01 (limit of quantitation) to 1.06 mg/g. Of these, the Al intake levels in two samples (cookie and scone mix, 1.3 and 2 mg/kg bw/week, respectively) exceeded the TWI as established by European Food Safety Authority, although the level in the scone mix was equivalent to the provisional TWI (PTWI) as established by Joint Food and Agriculture Organization of the United Nations/World Health Organization Expert Committee on Food Additives. The Al levels markedly decreased in 14 of the 19 samples with initially high Al levels. These results indicated reductions in the Al levels to below the PTWI limits in all but two previously identified food samples.


Assuntos
Compostos de Alumínio/química , Alumínio/análise , Aditivos Alimentares/química , Análise de Alimentos , Contaminação de Alimentos , Alumínio/toxicidade , Pão/efeitos adversos , Pão/análise , Pão/economia , Pão/normas , Pré-Escolar , Culinária , Dieta/efeitos adversos , Dieta/etnologia , Aditivos Alimentares/efeitos adversos , Aditivos Alimentares/normas , Análise de Alimentos/economia , Inspeção de Alimentos/métodos , Humanos , Hidrólise/efeitos da radiação , Indicadores e Reagentes/química , Internacionalidade , Limite de Detecção , Micro-Ondas , Ácido Nítrico/química , Nível de Efeito Adverso não Observado , Reprodutibilidade dos Testes , Lanches , Espectrofotometria Atômica , Tóquio
4.
Artigo em Inglês | MEDLINE | ID: mdl-26730677

RESUMO

A method was developed to determine the aromatic hydrocarbon to total hydrocarbon ratio of mineral oil in commercial lubricants; a survey was also conducted of commercial lubricants. Hydrocarbons in lubricants were separated from the matrix components of lubricants using a silica gel solid phase extraction (SPE) column. Normal-phase liquid chromatography (NPLC) coupled with an evaporative light-scattering detector (ELSD) was used to determine the aromatic hydrocarbon to total hydrocarbon ratio. Size exclusion chromatography (SEC) coupled with a diode array detector (DAD) and a refractive index detector (RID) was used to estimate carbon numbers and the presence of aromatic hydrocarbons, which supplemented the results obtained by NPLC/ELSD. Aromatic hydrocarbons were not detected in 12 lubricants specified for use for incidental food contact, but were detected in 13 out of 22 lubricants non-specified for incidental food contact at a ratio up to 18%. They were also detected in 10 out of 12 lubricants collected at food factories at a ratio up to 13%. The centre carbon numbers of hydrocarbons in commercial lubricants were estimated to be between C16 and C50.


Assuntos
Hidrocarbonetos Aromáticos/análise , Lubrificantes/química , Óleo Mineral/química , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida
5.
Shokuhin Eiseigaku Zasshi ; 53(1): 57-62, 2012.
Artigo em Japonês | MEDLINE | ID: mdl-22450671

RESUMO

The aluminium (Al) content of 105 samples, including bakery products made with baking powder, agricultural products and seafoods treated with alum, was investigated. The amounts of Al detected were as follows (limit of quantification: 0.01 mg/g): 0.01-0.37 mg/g in 26 of 57 bakery products, 0.22-0.57 mg/g in 3 of 6 powder mixes, 0.01-0.05 mg/g in all three agricultural products examined, 0.03-0.90 mg/g in 4 of 6 seafood samples, 0.01-0.03 mg/g in 3 of 11 samples of instant noodles, 0.04-0.14 mg/g in 3 of 4 samples of vermicelli, 0.01 mg/g in 1 of 16 soybean products, but none in soybeans. Amounts equivalent to the PTWI of a 16 kg infant were detected in two samples of bakery products, two samples of powder mixes and one sample of salted jellyfish, if each sample was taken once a week. These results suggest that certain foods, depending on the product and the intake, might exceed the PTWI of children, especially infants.


Assuntos
Alumínio/análise , Aditivos Alimentares/análise , Análise de Alimentos/métodos
6.
Shokuhin Eiseigaku Zasshi ; 50(5): 256-60, 2009 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-19897953

RESUMO

Pollution levels of toxic heavy metals (Pb, Cd, Hg) and arsenic in existing food additives used as food colors (40 samples of 15 kinds) were investigated. Heavy metals were detected in 8 samples; Pb in 1 sample (2.8 microg/g), Hg in 8 samples (0.1-3.4 microg/g) and arsenic in 2 samples (1.7, 2.6 microg/g). The Pb level in 1 sample of lac color (2.8 microg/g) exceeded the limit of 2 microg/g proposed by JECFA and Hg levels in 3 samples of cacao color (1.2-3.4 microg/g) exceeded the limit of 1 microg/g in the EU specification.


Assuntos
Arsênico/análise , Análise de Alimentos , Corantes de Alimentos/química , Contaminação de Alimentos/análise , Metais Pesados/análise , Cádmio/análise , Chumbo/análise , Mercúrio/análise , Espectrofotometria Atômica/métodos
7.
Shokuhin Eiseigaku Zasshi ; 49(5): 366-75, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19029790

RESUMO

Organic solvent residue levels in "Existing Food Additives" (n=145), health food materials (n=23), and commercial health food products (n=19) were surveyed. Ethanol was the dominant solvent found in the samples, suggesting its use in the manufacturing process. Methanol, acetone, 2-propanol and ethyl acetate was also found. No residual solvent exceeded the limits set by the Food Sanitation Law.


Assuntos
Resíduos de Drogas/análise , Aditivos Alimentares/análise , Alimentos Orgânicos/análise , Solventes/análise , 2-Propanol/análise , Acetatos/análise , Acetona/análise , Cromatografia Gasosa/métodos , Etanol/análise
8.
J AOAC Int ; 90(2): 437-45, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17474514

RESUMO

A fast and effective cleanup method was developed for the analysis of Sudan I, II, III, IV, and Para Red (Sudan dyes) in various foods and paprika color (oleoresin) by high-performance liquid chromatography (LC) with a diode array detector (DAD). Removal of fat or oil in fatty sample was a critical point for reducing the volume of the final sample solution in order to obtain a sufficient level of the analytes. Separation of fat or oil from the dyes with a silica gel solid-phase extraction (SPE) column seemed unfeasible, because elution profiles of oil, fat, and the dyes were similar. Finally, fat and oil were separated from the dyes by elution from the SPE column with n-hexane, not as intact compounds but as fatty acid methyl esters prepared by direct transesterification of acylglycerols in fat and oil, leaving the dyes on the column. The dyes were eluted with n-hexane-diethyl ether (9 + 1). Gradient elution with water and tetrahydrofuran was used for separation on a C18 column by LC. Measurement of spectral of 0.5 microg/g of Sudan dyes in foods and 1 microg/g in paprika color (oleoresin) with the DAD was achieved.


Assuntos
Compostos Azo/análise , Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Corantes/análise , Análise de Alimentos/métodos , Naftóis/análise , Extratos Vegetais/análise , Esterificação , Gorduras/metabolismo , Ácidos Graxos/análise , Contaminação de Alimentos , Glicerídeos/química , Dióxido de Silício/química , Extração em Fase Sólida
9.
J AOAC Int ; 89(2): 458-61, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16640294

RESUMO

A simple method for the determination of magnesium stearate in capsule- or tablet-type supplements was developed. Free stearic acid in the sample was removed by extraction with tetrahydrofuran. The remaining stearate was converted to stearic acid by reaction with a cation-exchange resin. The resulting stearic acid was determined by gas chromatography with a polar column. Esters of stearic acid were not converted to stearic acid and would not cause a positive error in the amount of stearate. The amount of magnesium stearate was calculated based on the stearic acid concentration thus obtained. Magnesium stearate levels in 5 out of 25 supplements exceeded 2500 microg/g, which indicated the possible admixture of magnesium stearate.


Assuntos
Suplementos Nutricionais/análise , Ácidos Esteáricos/análise , Calibragem , Cápsulas , Cromatografia por Troca Iônica , Cromatografia Gasosa-Espectrometria de Massas , Indicadores e Reagentes , Palmitatos/análise , Padrões de Referência , Comprimidos
10.
Shokuhin Eiseigaku Zasshi ; 47(6): 296-301, 2006 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-17228797

RESUMO

Contents of minerals (Mg, Ca, Na and K), anions (SO4(2-), Br- and Cl) and heavy metals (Pb, Cd, Zn, Hg and As) were determined in 17 commercial samples of Nigari, 15 samples of crude magnesium chloride (sea water) products as a food additive and 2 magnesium-containing foods. Obtained values were compared with the specifications proposed in a draft of the eighth edition of Japan's Specifications and Standards for Food Additives. Out of 15 food additive samples, only 5 samples satisfied the specification. Since the Joint FAO/WHO Expert Committee on Food Additives (JECFA) proposed to lower the limits of heavy metals in food additives, a simple method was developed for the determination of low levels of Pb and Cd by extracting chelates of these metals with organic solvents. The quantification limits for Pb and Cd were 0.5 microg/g and 0.05 microg/g, respectively. It was estimated from the SO4(2-)/Ca ratios that 15 samples were sea water evaporation products, and the remaining 2 were ion-exchange membrane process products. No pollution with heavy metals was found in any of the samples.


Assuntos
Aditivos Alimentares/análise , Análise de Alimentos , Cloreto de Magnésio/análise , Água do Mar/análise , Metais Pesados/análise , Espectrofotometria Atômica , Poluentes Químicos da Água/análise
11.
Shokuhin Eiseigaku Zasshi ; 46(4): 133-8, 2005 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-16180682

RESUMO

Migration from multi-layer laminated film pouches intended for retort foods was investigated through HPLC analysis with a fluorescence detector, and measurements of residue on evaporation, consumption of potassium permanganate and total organic carbon. HPLC analysis revealed that the levels of migrants in oil and the water which were heated in the pouches (121 degrees C, 30 min) were ten times of those in the corresponding official simulants under the official conditions; n-heptane (25 degrees C, 60 min), and water (95 degrees C, 30 min). Bisphenol A diglycidyl ether and related compounds were found in the oil and the water heated in the pouches, as well as in the simulants. These compounds were thought to have been present in the adhesive between the laminated films, and migrated through the food-contact film of the package. Consumption of potassium permanganate and residue on evaporation of the heated water were ten times of those of the water simulant, while the total organic carbon level of the heated water was several-hold greater than that of the water simulant. In addition, migrant levels per surface area of the pouch were one-fourth of the concentrations per content volume of the pouch. Since compliance with the legal limits is evaluated based on the concentration per surface area, real migration into foods would be underestimated by a factor of another four.


Assuntos
Compostos de Epóxi/análise , Análise de Alimentos/métodos , Embalagem de Alimentos , Conservação de Alimentos , Compostos Benzidrílicos , Cromatografia Líquida de Alta Pressão/métodos
12.
Eur J Immunol ; 35(2): 644-54, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15668918

RESUMO

Despite the important role in the development and activation of T cells, NK cells, mast cells, and macrophages, the expression and function of SLP-76 in B cells have been largely unknown. Here we demonstrate that SLP-76 is expressed in all mouse B cell lines tested and in normal splenic B cells, and serves as an SHP-1 substrate. Dephosphorylation of SLP-76 by SHP-1 inhibits its association with Nck, down-regulating c-Jun N-terminal kinase (JNK) activation and exerting a positive effect on apoptosis. Knockdown of SLP-76 in WEHI-231 cells by small interfering RNA attenuated JNK activation, but showed little effects on extracellular signal-regulated kinase (ERK) or p38 activation. Although WEHI-231 does not express linker for activation of T cells (LAT), SLP-76 localizes in membrane fraction, which increases following B cell receptor (BCR) cross-linking. Further analyses revealed that SLP-76 complexed with Gads is associated with tyrosine-phosphorylated CD22 through the SH2 domains of SLP-76 and Gads. Given that SHP-1 binds to CD22 upon BCR ligation, our findings suggest that dephosphorylation of SLP-76 recruited to CD22 by SHP-1 inhibits BCR-induced JNK activation, dictating apoptosis.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos B/metabolismo , Linfócitos B/metabolismo , Moléculas de Adesão Celular/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lectinas/metabolismo , Ativação Linfocitária/fisiologia , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Proteínas Oncogênicas/metabolismo , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteínas Tirosina Fosfatases , Receptores de Antígenos de Linfócitos B/metabolismo , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico , Transdução de Sinais/fisiologia , Tirosina/metabolismo
13.
Int Immunol ; 16(7): 971-82, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15148289

RESUMO

CD72 is a 45 kDa B cell-specific type II transmembrane protein of the C-type lectin superfamily. It was originally defined as a receptor-like molecule that regulates B cell activation and differentiation; however, its precise function remains unclear since more recent functional analyses, including a gene targeting study, suggest that CD72 may serve as a negative or a positive regulator of B cell signaling. In the present study, we analyzed the cell-autonomous function of CD72 in B cell receptor (BCR) signaling using CD72-deficient cells generated from mature BAL-17 cells. We found that BCR-mediated phosphorylation of CD19, Btk, Vav and phospholipase Cgamma2 and association of CD19 with phosphatidylinositol-3 kinase were impaired in CD72-deficient cells. Inositol trisphosphate synthesis was normally induced initially but ablated at 1 min of stimulation in CD72-deficient cells. In the event, Ca(2+) release from intracellular stores remained intact, though influx of extracellular Ca(2+) was severely impaired in CD72-deficient cells. Furthermore, BCR-evoked activation of mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase and c-Jun NH(2)-terminal kinase, and growth inhibition in BAL-17 cells were blocked in the absence of CD72. Significantly, these effects were largely reversed by re-expression of CD72. Thus, CD72 appears to exert a positive effect on BCR signaling pathways leading to Ca(2+) influx and MAPK activation, which in turn may determine the fate of BAL-17 cells.


Assuntos
Sinalização do Cálcio/imunologia , Processos de Crescimento Celular/imunologia , Lectinas Tipo C/imunologia , Proteínas Quinases Ativadas por Mitógeno/imunologia , Receptores de Antígenos de Linfócitos B/deficiência , Receptores de Antígenos de Linfócitos B/imunologia , Animais , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Camundongos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-vav
14.
Blood ; 103(4): 1425-32, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-14563648

RESUMO

CD45 is a key protein tyrosine phosphatase regulating Src-family protein tyrosine kinases (Src-PTKs) in lymphocytes; precisely how it exerts its effect remains controversial, however. We previously demonstrated that CD45 negatively regulates Lyn in the WEHI-231 B-cell line. Here we show that negative regulation by CD45 is physiologically significant in B cells and that some CD45 is constitutively associated with glycolipid-enriched microdomains (GEMs), where it inhibits Src-PTKs by dephosphorylating both the negative and the positive regulatory sites. Upon B-cell receptor (BCR) ligation, however, CD45 dissociates from GEMs within 30 seconds, inducing phosphorylation of 2 regulatory sites and activation of Src-PTKs, but subsequently reassociates with the GEMs within 15 minutes. Disruption of GEMs with methyl-beta-cyclodextrin results in abrogation of BCR-induced apoptosis in WEHI-231 cells, suggesting GEMs are critical to signals leading to the fate determination. We propose that the primary function of CD45 is inhibition of Src-PTKs and that the level of Src-PTK activation and the B-cell fate are determined in part by dynamic behavior of CD45 with respect to GEMs.


Assuntos
Linfócitos B/enzimologia , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/metabolismo , Quinases da Família src/metabolismo , Animais , Apoptose/imunologia , Linfócitos B/citologia , Linhagem Celular , Microdomínios da Membrana , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfoproteínas/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Baço/citologia , Baço/imunologia
15.
J Immunol ; 169(2): 778-86, 2002 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12097380

RESUMO

Src homology region 2 domain-containing phosphatase 1 (SHP-1) is a key mediator in lymphocyte differentiation, proliferation, and activation. We previously showed that B cell linker protein (BLNK) is a physiological substrate of SHP-1 and that B cell receptor (BCR)-induced activation of c-Jun NH(2)-terminal kinase (JNK) is significantly enhanced in cells expressing a form of SHP-1 lacking phosphatase activity (SHP-1-C/S). In this study, we confirmed that SHP-1 also exerts negative regulatory effects on JNK activation in splenic B cells. To further clarify the role of SHP-1 in B cells, we examined how dephosphorylation of BLNK by SHP-1 affects downstream signaling events. When a BLNK mutant (BLNK Delta N) lacking the NH(2)-terminal region, which contains four tyrosine residues, was introduced in SHP-1-C/S-expressing WEHI-231 cells, the enhanced JNK activation was inhibited. Among candidate proteins likely to regulate JNK activation through BLNK, Nck adaptor protein was found to associate with tyrosine-phosphorylated BLNK and this association was more pronounced in SHP-1-C/S-expressing cells. Furthermore, expression of dominant-negative forms of Nck inhibited BCR-induced JNK activation. Finally, BCR-induced apoptosis was suppressed in SHP-1-C/S-expressing cells and coexpression of Nck SH2 mutants or a dominant-negative form of SEK1 reversed this phenotype. Collectively, these results suggest that SHP-1 acts on BLNK, modulating its association with Nck, which in turn negatively regulates JNK activation but exerts a positive effect on apoptosis.


Assuntos
Apoptose/imunologia , Proteínas de Transporte/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Oncogênicas/metabolismo , Fosfoproteínas/metabolismo , Proteínas Tirosina Fosfatases/fisiologia , Receptores de Antígenos de Linfócitos B/fisiologia , Regulação para Cima/imunologia , Domínios de Homologia de src/imunologia , Proteínas Adaptadoras de Transdução de Sinal , Adjuvantes Imunológicos/fisiologia , Animais , Linfócitos B/citologia , Linfócitos B/enzimologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Proteínas de Transporte/fisiologia , Regulação para Baixo/imunologia , Ativação Enzimática/imunologia , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Quinases JNK Ativadas por Mitógeno , Camundongos , Camundongos Endogâmicos C3H , Camundongos Mutantes , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Proteínas Oncogênicas/fisiologia , Fragmentos de Peptídeos/fisiologia , Fosfoproteínas/fisiologia , Proteína Fosfatase 1 , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Baço/citologia , Baço/enzimologia , Baço/imunologia , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/enzimologia , Células Tumorais Cultivadas/metabolismo
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