RESUMEN
We have started the construction of a nationwide forensic soil sediment database for Japan based on the heavy mineral and trace heavy element compositions of stream sediments collected at 3024 points all over Japan obtained by high-resolution synchrotron X-ray powder diffraction (SR-XRD) and high-energy synchrotron X-ray fluorescence analysis (HE-SR-XRF). In this study, the performance of both techniques was demonstrated by analyzing soil sediments from two different geological regions, the Kofu and Chiba regions in Kanto province, to construct database that can be applied in the future to provenance analysis of soil evidence from a crime scene. The sediments from the quaternary volcanic lithology of the Chiba region were found to be dominated by heavy minerals of volcanic origin - orthopyroxene, clinopyroxene, and amphibole, and the REEs (rare earth elements) within the region showed similar geochemical behavior. On the other hand, four distinct heavy mineral groups were identified in the sediments of the Kofu region, where there is a great variety of underlying bedrock, and the geochemical behavior of the REEs in the sediments also varied accordingly to their geological origins. As such, our study shows that high-resolution SR-XRD data can provide information on the spatial distribution patterns of heavy minerals in stream sediments, playing an important role in determining their likely geographical origin. Meanwhile, the highly sensitive HE-SR-XRF data allow us to study the geochemical behavior of trace heavy elements, especially the REEs in the sediments, providing additional support to further constrain the likely geographical origin of the sediments determined by heavy minerals.
RESUMEN
The peptide product, Valtyron, is obtained via enzymatic hydrolysis of sardine muscle. Although the safety and efficacy of the sardine peptide product have been evaluated in human studies, sardine peptides have not been identified as the subject of toxicological testing. In this study, the sardine peptide product did not exhibit any mutagenic activity in Salmonella typhimurium or Escherichia coli WP2uvrA. Likewise, the sardine peptide product was not associated with clastogenic properties in mouse bone marrow cells in a micronucleus assay. An oral rat LD(50) value of greater than 10,000 mg per kilogram of body weight was determined for peptide alpha-1000, and in rats administered peptide alpha-1000 by gavage at levels up to 5000 mg per kilogram of body weight per day for 28 days, no compound-related differences were observed in standard toxicological parameters. The results of these studies support the safety of the sardine peptide product for use in food for human consumption as a dietary source of peptides available from sardines.
Asunto(s)
Peces , Proteínas Musculares/toxicidad , Oligopéptidos/toxicidad , Fragmentos de Péptidos/toxicidad , Administración Oral , Animales , Médula Ósea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Femenino , Peces/metabolismo , Hidrólisis , Dosificación Letal Mediana , Masculino , Ratones , Ratones Endogámicos ICR , Micronúcleos con Defecto Cromosómico/inducido químicamente , Proteínas Musculares/química , Proteínas Musculares/aislamiento & purificación , Pruebas de Mutagenicidad , Oligopéptidos/química , Oligopéptidos/aislamiento & purificación , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Ratas , Ratas Sprague-Dawley , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad CrónicaRESUMEN
An enzymatic hydrolysate of sardine protein (sardine peptide, SP) derived from sardine muscle possesses angiotensin I-converting enzyme (ACE) inhibitory activity. In the present study, we investigated the effect of SP on the blood glucose levels in stroke-prone spontaneously hypertensive rats (SHRSPs). Ten-week-old SHRSPs were assigned to three groups. The control group was given tap water for 4 weeks, while the experimental groups were given water containing SP (1 g/kg/d) or an ACE inhibitor, captopril (8 mg/kg/d). Treatment with SP and captopril decreased ACE activity in the kidney, aorta, and mesentery. There were no differences in fasting blood glucose levels among the three groups, whereas SP and captopril administration significantly suppressed the increase in blood glucose after glucose loading in the control SHRSPs. No difference was observed in plasma insulin levels among the three groups. Thus treatment with captopril and ACE-inhibitory sardine peptides ameliorated the glucose tolerance of this rat strain.
Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Glucemia/metabolismo , Peces , Péptidos/farmacología , Peptidil-Dipeptidasa A/metabolismo , Accidente Cerebrovascular/complicaciones , Animales , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Captopril/farmacología , Cardiomegalia/complicaciones , Hiperglucemia/complicaciones , Hipertensión/sangre , Hipertensión/complicaciones , Hipertensión/patología , Enfermedades Renales/complicaciones , Masculino , Tamaño de los Órganos/efectos de los fármacos , Peptidil-Dipeptidasa A/sangre , Ratas , Ratas Endogámicas SHRRESUMEN
High-energy synchrotron radiation x-ray fluorescence spectrometry (SR-XRF) utilizing 116 keV x-rays was used to characterize titanium dioxide pigments (rutile) and automotive white paint fragments for forensic examination. The technique allowed analysis of K lines of 9 trace elements in 18 titanium dioxide pigments (rutile), and 10 trace elements in finish coat layers of seven automotive white paint fragments. High-field strength elements (HFSE) were found to strongly reflect the origin of the titanium dioxide (TiO(2)) pigments, and could be used as effective parameters for discrimination and classification of the pigments and paint fragments. A pairwise comparison of the finish coat layers of seven automotive white paint fragments was performed. The trace elements in the finish coat layers detected by the high-energy SR-XRF were especially effective for identification. By introducing the trace element information of primer and electrocoat layers, all the automotive white paint fragments could be discriminated by this technique.
RESUMEN
Total reflection X-ray fluorescence spectrometry (TXRF) has been applied for trace elemental analysis of small glass fragments. A small glass sample (a fragment with weight less than 0.5 mg) was decomposed by 100 microg of HF/HNO3 acid; the material was condensed to 10 microl and was dried on a Si wafer. Since the size of the dried residue on the Si wafer was less than 1 cm in diameter, an incident X-ray beam with about 1 cm in width could effectively excite elemental components in such a small glass fragment. The precision of the present technique was checked by analyzing the glass fragments (<0.5 mg) from NIST SRM612; the relative standard deviations (RSD) of less than 8.1% were achieved for elemental ratios that were normalized by Sr. Fragments (<0.5 mg) obtained from 23 figured sheet glasses were used as samples for estimating the utility of this technique to forensic discrimination. Comparison of five elemental ratios of Ti/Sr, Mn/Sr, Zn/Sr, Rb/Sr, and Pb/Sr calculated from X-ray fluorescence spectra was effective in distinguishing glass fragments that could not be differentiated by their refractive indexes (RI).
RESUMEN
Fourier-transform (FF) Raman spectroscopy and chemometrics were used for nondestructive analysis of ivories. The discrimination of five kinds of ivories, two subspecies of African elephant, mammoth, hippopotamus, and sperm whale, was investigated, and a calibration model for predicting their specific gravity was developed. FT-Raman spectra were measured in situ for them and chemometrics analyses were carried out for the 3050-350 cm(-1) region. The five kinds of ivories were clearly discriminated from each other on the scores plots of two or three principal components (PCs) obtained by principal component analysis (PCA). The loadings plot for PC 1 shows that the discrimination relies on the content ratio of organic collagenous protein and inorganic hydroxyapatite of ivories. The loadings plot for PC 2 shows that bands due to the CH3 and CH2 stretching modes of the protein also play a role in the discrimination. Using partial least squares regression (PLSR), we developed a calibration model that predicts the specific gravity of the ivories from the FT-Raman spectra. The correlation coefficient and root mean square error of cross validation (RMSECV) of this model were 0.980 and 0.024, respectively.
Asunto(s)
Elefantes , Diente/química , Animales , Análisis de Fourier , Especificidad de la Especie , Gravedad Específica , Espectroscopía Infrarroja por Transformada de Fourier/métodosRESUMEN
Synchrotron radiation total reflection X-ray fluorescence spectroscopy (SR-TXRF) was utilized to analyze various trace elements in small amounts of drugs of abuse. Sample amounts of 1 microL solutions containing 10 microg of drugs (methamphetamine, amphetamine, 3,4-methylenedioxymethamphetamine, cocaine, and heroin) were spotted on silicon wafers for direct analysis. In addition, a leaflet of marijuana was set directly on a silicon wafer, and opium in the form of a soft lump was smeared on another silicon wafer for analysis. In these experiments, about 10 pg of contaminant elements could be detected. For example, in a seized methamphetamine sample, iodine was found, which could be indicative of synthetic route. In seized 3,4-methylenedioxymethamphetamine samples, variable amounts of phosphorus, calcium, sulfur, and potassium were found, which could not be detected in a control 3,4-methylenedioxymethamphetamine sample. For marijuana and opium, two spectral patterns were obtained that were far different from each other and could be easily discriminated. Using SR-TXRF, pg amounts of each trace element in 10 microg of various drugs can be easily detected, which is not the case either for a standard TXRF experimental system or for other elemental analysis techniques.
RESUMEN
Escherichia coli strain K4 produces the K4 antigen, a capsule polysaccharide consisting of a chondroitin backbone (GlcUA beta(1-3)-GalNAc beta(1-4))(n) to which beta-fructose is linked at position C-3 of the GlcUA residue. We molecularly cloned region 2 of the K4 capsular gene cluster essential for biosynthesis of the polysaccharide, and we further identified a gene encoding a bifunctional glycosyltransferase that polymerizes the chondroitin backbone. The enzyme, containing two conserved glycosyltransferase sites, showed 59 and 61% identity at the amino acid level to class 2 hyaluronan synthase and chondroitin synthase from Pasteurella multocida, respectively. The soluble enzyme expressed in a bacterial expression system transferred GalNAc and GlcUA residues alternately, and polymerized the chondroitin chain up to a molecular mass of 20 kDa when chondroitin sulfate hexasaccharide was used as an acceptor. The enzyme exhibited apparent K(m) values for UDP-GlcUA and UDP-GalNAc of 3.44 and 31.6 microm, respectively, and absolutely required acceptors of chondroitin sulfate polymers and oligosaccharides at least longer than a tetrasaccharide. In addition, chondroitin polymers and oligosaccharides and hyaluronan polymers and oligosaccharides served as acceptors for chondroitin polymerization, but dermatan sulfate and heparin did not. These results may lead to elucidation of the mechanism for chondroitin chain synthesis in both microorganisms and mammals.