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1.
Food Chem ; 399: 133963, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36029676

RESUMEN

Control and n-3 PUFA enriched raw material was used to manufacture clean label and conventional salami; the former were added with a phytocomplex having iron chelating, DPPH, and FRAP activity, obtained from olive vegetation water, oregano, green tea and blueberry leaves, and with acerola powder. Salami were dried at 3 ± 1 °C until an established decrease in the combined pH and aw values, while only the conventional ones underwent a standard process. In the cold dried salami pH changes, aw and weight decrease were delayed; the phytocomplex contributed to lower the pH, and to prevent lipid and protein oxidation, despite the n-3 PUFA enrichment and heme iron release due to nitrite removal. TBARS and protein carbonyls were the highest in the nitrite-added salami undergoing cold and standard drying, respectively. The oxidation marker MDA tended to increase in the simulated digests of salami n-3 PUFA enriched or subjected to cold drying.


Asunto(s)
Ácidos Grasos Omega-3 , Carne de Cerdo , Carne Roja , Animales , Antioxidantes , Nitritos , Porcinos
2.
Meat Sci ; 161: 107994, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31809914

RESUMEN

The objective of the study was to reduce the salt content of typical Italian dry-cured ham by at least 25%, to meet the "reduced salt" claim. Salt reduction needs process adjustments to maintain product safety and quality in the absence of nitrites. A way was to reduce the salt input and to shorten the salting period compared to the conventional process. The cold drying period of reduced salt (RS) hams was extended, to decrease aw below 0.97 in inner parts and obtain the same safety conditions of control hams (CS). In RS dry-cured hams the salt reduction was accomplished, the generation of biogenic amines was lower than the threshold values generating toxic effects, and color was the same as in the CS ones. However, in RS proteolysis increased, contributing to texture softening. A strengthened salt diffusion from backside rind could contribute to counteract the rise in proteolysis of biceps femoris muscle, depleted of salt during the process of RS hams.


Asunto(s)
Frío , Manipulación de Alimentos/métodos , Conservación de Alimentos/métodos , Calidad de los Alimentos , Carne de Cerdo/análisis , Cloruro de Sodio/administración & dosificación , Animales , Color , Italia , Productos de la Carne/análisis , Proteolisis , Porcinos , Factores de Tiempo
3.
Environ Technol ; 35(5-8): 851-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24645467

RESUMEN

This study is aimed at optimizing a low energy sonication (LES) treatment for granular activated carbon (GAC)-colonizing biomass detachment and determination, evaluating detachment efficiency and the effects of ultrasound exposure on bacterial cell viability. GAC samples were collected from two filters fed with groundwater. Conventional heterotrophic plate count (HPC) and fluorescence microscopy with a double staining method were used to evaluate cell viability, comparing two LES procedures, without and with periodical bulk substitution. A 20 min LES treatment, with bulk substitution after cycles of 5 min as maximum treatment time, allowed to recover 87%/100% of attached biomass, protecting detached bacteria from ultrasound damaging effects. Observed viable cell inactivation rate was 6.5/7.9% cell/min, with membrane-compromised cell damage appearing to be even higher (11.5%/13.1% cell/min). Assessing bacterial detachment and damaging ultrasound effects, fluorescence microscopy turned out to be more sensitive compared to conventional HPC. The optimized method revealed a GAC-colonizing biomass of 9.9 x 10(7) cell/gGAC for plant 1 and 8.8 x 10(7) cell/gGAC for plant 2, 2 log lower than reported in literature. The difference between the two GAC-colonizing biomasses is higher in terms of viable cells (46.3% of total cells in plant 1 GAC-colonizing biomass compared to the 33.3% in plant 2). Studying influent water contamination through multivariate statistical analyses, apossible combined toxic and genotoxic effect of chromium VI and trichloroethylene was suggested as a reason for the lower viable cell fraction observed in plant 2 GAC-colonizing population.


Asunto(s)
Biomasa , Carbono/química , Sonicación/métodos , Purificación del Agua/métodos , Adsorción , Bacterias/metabolismo , Agua Potable , Filtración , Cinética , Microscopía Fluorescente , Análisis Multivariante , Factores de Tiempo , Microbiología del Agua , Contaminantes Químicos del Agua/química , Abastecimiento de Agua
4.
J Chromatogr A ; 1082(1): 43-50, 2005 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-16038193

RESUMEN

A new method for simultaneous determination of underivatized biogenic amines based on the separation by cation-exchange chromatography and suppressed conductivity coupled with mass spectrometry detection has been developed. The method has been applied to the analysis of cadaverine, putrescine, histamine, agmatine, phenethylamine and spermidine in processed meat products. The amines were extracted from muscle tissue with methanesulfonic acid without any additional derivative step or sample clean-up. Biogenic amines were separated by the IonPac CS17 column, a cation-exchange column used with gradient elution, and detection was done by suppressed conductivity and mass spectrometry. Tyramine was simultaneously analysed by using a spectrophotometer (275 nm) before the suppressed conductivity detection. Linearity of response was obtained in the range 0.25-25 microg mL(-1). The detection limits ranged from 23 microg L(-1) for putrescine to 155 microg L(-1) for spermidine (suppressed conductivity) and from 9 microg L(-1) for agmatine to 34 microg L(-1) for spermidine (MS). Average recoveries from meat samples ranged from 85 to 97% and coefficients of variation ranged from 4.5 to 9.7%. The analysis of biogenic amines in fresh and processed meats (dry-cured, cooked and fermented products) can be used as a quality marker of raw material and for studying the relationship between their changes and the fermentation process involved in dry sausage ripening.


Asunto(s)
Aminas Biogénicas/análisis , Cromatografía por Intercambio Iónico/métodos , Espectrometría de Masas/métodos , Productos de la Carne/análisis , Carne/análisis , Animales , Culinaria , Porcinos , Rayos Ultravioleta
5.
J Chromatogr A ; 1039(1-2): 155-9, 2004 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-15250418

RESUMEN

Acrylamide, a known neurotoxin and putative human carcinogen, has been included among the substances to be monitored in drinking water according to the European Union Directive 98/83 on potable water. This paper reports a new method based on the combination of ion-exclusion chromatographic separation and MS detection. Samples of drinking water have been directly injected in the microbore ICE-AS1 column and detected in the selected-ion monitoring mode by a single quadrupole system with electrospray ionization. Chromatographic conditions, such as eluent composition and flow rate, have been optimized by a central composite design experiment. Statistical analysis of data showed that the amount of acetonitrile fraction in the eluent mixture, composed by acetonitrile and formic acid solution, is the variable that most influences retention of the acrylamide peak. After optimization of MS detection parameters, this method has been validated for spiked drinking water samples. The effect of large-volume injection (up to 500 microl) has been also explored. Linearity was evaluated from 0.5 to 5 microg l(-1). Repeatability, expressed as R.S.D., was 16 and 12% at 0.5 and 1 microg l(-1) respectively. The limit of detection was 0.20 ppb with 500 microl injection volume.


Asunto(s)
Acrilamida/análisis , Cromatografía por Intercambio Iónico/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Abastecimiento de Agua/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
Ann Oncol ; 14(1): 85-90, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12488298

RESUMEN

BACKGROUND: It has been suggested that progression of superficial bladder cancer may be regulated at the molecular level by a typical pattern of expression of genes involved in apoptosis. Recently LIVIN, belonging to the inhibitors of apoptosis (IAP) family, has been found to be expressed in most solid tumors, where its expression is suggested to have prognostic significance. No data are available concerning the significance of LIVIN in the progression of bladder tumors. PATIENTS AND METHODS: In the present paper we used RT-PCR to investigate the expression of LIVIN isoforms alpha and beta, SURVIVIN, BCL-X and BCL-2/BAX expression ratio both in normal and tumoral bladder tissues, and correlated their expression with the emergence of early relapses in a follow-up of 4 years. This study shows that only the alpha isoform of LIVIN, which is not expressed in normal bladder tissue, is expressed in a proportion of tumors with a high risk of relapse. RESULTS: LIVIN was found in 7/30 patients (23%), SURVIVIN in 9/30 (30%), BCL-2/BAX ratio >1 in 16/30 (53%), BCL-2/BAX expression ratio <1 in 14/30 (46.6%) and BCL-X, only in isoform BCL-X(L), in 11/30 (36.6%). When we evaluated the dependence between each gene expression and relapse free time of patients, we found that LIVIN, high BCL-2/BAX ratio and BCL-X(L), but not SURVIVIN, reached statistical significance in order to predict relapses. CONCLUSIONS: Our findings suggest that LIVIN may be involved in the progression of superficial bladder cancer and used as a marker of early recurrence; while the expression of SURVIVIN cannot be used to identify patients with high risk of relapse.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Apoptosis/genética , Carcinoma de Células Transicionales/genética , Proteínas Portadoras/genética , Proteínas Asociadas a Microtúbulos/genética , Proteínas de Neoplasias/genética , Neoplasias de la Vejiga Urinaria/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Transicionales/metabolismo , Carcinoma de Células Transicionales/patología , Proteínas Portadoras/metabolismo , Cartilla de ADN/química , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas Inhibidoras de la Apoptosis , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Persona de Mediana Edad , Proteínas de Neoplasias/metabolismo , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Pronóstico , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Mensajero/metabolismo , ARN Neoplásico/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Survivin , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Proteína X Asociada a bcl-2 , Proteína bcl-X
7.
Meat Sci ; 64(4): 483-90, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22063131

RESUMEN

The spectral and extraction properties of nitrate-free dried hams (Parma hams) were studied as a function of maturing time and muscle type (semimembranosus and biceps femoris muscles). To understand the red colour of the processed meat, a three-step extraction using water, acetone and tetrahydrofuran (THF) as solvents was employed and the extracts from each step were submitted to spectrophotometric (visible) analysis while the corresponding residues underwent instrumental (CIE L* a* b*) colour evaluation. Results showed that the drier the meat the more the pigment is soluble in organic solvents, THF proving a major extractant in matured hams, regardless of muscle type. When Parma hams were compared with hams made using nitrate, the former displayed more intense (P<0.05) absorption in the red region in the aqueous solution, lower intensities in acetone and higher values in THF solution. Major differences in spectral characteristics were found between water and organic extracts of Parma hams, with both acetone and THF solutions exhibiting a doublet at 544-584 nm, and water extracts displaying two distorted peaks at 551 and 595 nm. It is concluded that dry curing of meat without nitrate yields a lipophylic stable red pigment whose hydrophobicity increases with ageing.

8.
J Steroid Biochem Mol Biol ; 74(3): 149-55, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11086234

RESUMEN

Uridine diphosphoglucuronosyltransferases (UGTs) are detoxifying enzymes responsible for the metabolism of endogenous and xenobiotics compounds. UGT isoforms are widely distributed in rat tissues showing a constitutive and inducible gene expression. However, little information is available concerning UGTs expression in testis. The UGT1A1, UGT1A2, and UGT1B1 mRNAs expression in whole rat testis, in Sertoli and peritubular myoid cells in basal conditions, and after hormonal and hypoxic stimulation were investigated by reverse transcriptase-polymerase chain reaction (RT-PCR). Constitutive expression of each UGT1 isoform was present in rat testis with higher levels of UGT1A2. UGT transcripts were also detected in Sertoli and peritubular myoid cells. After FSH stimulation, Sertoli cells showed an increase in UGT1B1 mRNA expression, whereas the levels of UGT1A1 and UGT1A2 resulted unmodified. The main effect induced by testosterone was a decrease of UGT1B1 mRNA expression in peritubular myoid cells, whereas in Sertoli cells an increase in UGT1A1 and UGT1B1 was observed. In hypoxic conditions, a reduction in UGTs mRNA levels was detected in both cell types. These findings suggest that rat UGT1 isoforms are regulated in testis by hormonal and environmental factors. Thus, it was speculated that alterations in UGTs expression and/or activity may be involved in the pathogenesis of testis injury.


Asunto(s)
Hormona Folículo Estimulante/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Glucuronosiltransferasa/genética , Oxígeno/metabolismo , Células de Sertoli/efectos de los fármacos , Células de Sertoli/enzimología , Testosterona/farmacología , Animales , Células Cultivadas , Perfilación de la Expresión Génica , Isoenzimas/genética , Masculino , Oxígeno/farmacología , ARN Mensajero/análisis , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células de Sertoli/metabolismo , Testículo/citología , Testículo/efectos de los fármacos , Testículo/enzimología , Testículo/metabolismo
9.
Int J Oncol ; 14(6): 1123-7, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10339668

RESUMEN

Natural history of bladder cancer is characterized by high risk of disease progression even for patients with a clinical diagnosis of superficial disease; in these tumors, the occurrence of local relapse is known to be dependent on the angiogenesis rate. Basic fibroblast growth factor (bFGF), has been described to be elevated in urine and serum of patients with bladder cancer. We investigated the expression of bFGF at mRNA level in a panel of 32 transitional cell tumors of the urinary bladder and in normal bladder tissues used as controls. Expression of bFGF was found elevated in most tumors of high stage, where its presence was found correlated with the occurrence of early local relapses. Furthermore, bFGF was found highly expressed in the majority of tumors showing a high bcl-2 expression rate. Our data suggest that bFGF expression could contribute to the progression of disease; it may provide a prognostic indicator in the identification of patients with high risk for occurrence of local relapses.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/biosíntesis , Recurrencia Local de Neoplasia/metabolismo , ARN Mensajero/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Adulto , Anciano , Femenino , Factor 2 de Crecimiento de Fibroblastos/genética , Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/cirugía , Microglobulina beta-2/biosíntesis , Microglobulina beta-2/genética
10.
J Chromatogr A ; 770(1-2): 243-52, 1997 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-9203364

RESUMEN

Fruit juices and purees are defined as fermentable, but unfermented, products obtained by mechanical processing of fresh fruits. The presence of undesired metabolites derived from microbial growth can arise from the use of unsuitable fruit or from defects in the production line or subsequent contamination. This involves a loss in the overall quality that cannot be resolved by thermal treatment following the start of fermentation. With these considerations, together with microbiological control, the analysis of different metabolites, which can be considered as microbial growth markers, such as alcohols (i.e. ethanol, etc.), acids (i.e. acetic, fumaric, lactic, etc.) is fundamental in order to achieve a better evaluation of product quality. Enzymatic determination and other single-component analytical techniques are often used for the determination of these metabolites. When the microbial spoilage is not well known, this results in a long and cumbersome procedure. A versatile technique that is capable of determining many metabolites in one analysis could be helpful in improving routine quality control. For this purpose, an ion chromatographic technique, such as ion exclusion, for separation, and diode array spectrophotometry and conductivity, for detection, were evaluated. Both different industrial samples and inoculated samples were analyzed.


Asunto(s)
Ácido Acético/análisis , Bebidas/análisis , Microbiología de Alimentos , Frutas/química , Frutas/microbiología , Fumaratos/análisis , Ácido Láctico/análisis , Cromatografía por Intercambio Iónico/métodos , Conductividad Eléctrica , Industria de Procesamiento de Alimentos , Frutas/metabolismo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta
11.
Int J Oncol ; 11(6): 1271-7, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21528334

RESUMEN

32DCl3(G) is an interleukin-3 (IL-3) dependent, non-tumorigenic murine hematopoietic cell line which undergoes terminal differentiation into granulocytes when exposed to granulocyte-colony stimulating factor (G-CSF). This line therefore offers a convenient system to study the expression of genes involved in apoptosis and differentiation. In our experiments we have acquired evidence that during the differentiation pathway, likewise in apoptosis induced by IL-3 deprivation, detectable levels of bax mRNA appear, while bcl-2 expression decreases. These events are under the control of the p53 tumor-suppressor gene. In these cells, an overexpression of exogenous wild-type p53 leads to a decrease in bcl-2 mRNA and to the appearance of box mRNA, which instead is absent in the parental cells growing in IL-3 conditioned medium. Furthermore, results from experiments on p53 transfected cells demonstrate that excess wild-type p53 activity, on its own, fails to elicit apoptosis as long as IL-3 is present and does not induce differentiation if G-CSF is not added to the culture medium. We conclude that in apoptosis and differentiation of 32DCl3(G) the alterate ratio of bcl-2 and box gene expression, modulated by p53, is an early event dependent on IL-3 withdrawal and that the appearance of bax and the decrease of bcl-2 expression are necessary, but not sufficient for the acquisition of a completely mature granulocytic phenotype.

12.
Circ Res ; 75(6): 1050-63, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7955143

RESUMEN

Proliferating cell nuclear antigen (PCNA) is a late growth-regulated gene that is expressed at the G1-S boundary of the cell cycle and is required for DNA synthesis and cell proliferation. Since quantitative results suggest that myocyte hyperplasia occurs in the decompensated human heart, we postulated that induction of the PCNA gene may be present in the failing heart in humans. PCNA protein was detected in myocardial samples obtained from the left and right ventricles of patients with congestive heart failure. Endomyocardial biopsies collected from donor subjects were used as control tissue. The percentage of positively stained myocyte nuclei in the ventricles was established by using PCNA monoclonal antibody and the immunoperoxidase technique. The localization of PCNA in myocytes was confirmed by alpha-sarcomeric actin antibody staining. PCNA labeling was present in left ventricular myocytes of 29 of the 32 hearts examined. In the right ventricle, 24 of the 29 samples showed positive staining. In a subset of 25 patients, the percentage of PCNA-labeled myocyte nuclei was measured and found to constitute 49 +/- 22% of left ventricular myocytes. A similar analysis for the right ventricle, conducted in 21 patients, showed that 49 +/- 19% of the myocyte nuclei exhibited PCNA protein. In addition, mitotic figures in myocytes were documented. A quantitative analysis of this cellular process revealed that 11 myocyte nuclei per 1 million cells exhibited mitotic images in chronic heart failure. Immediately after myocardial infarction, two cells per million showed mitotic division, and this phenomenon was restricted to the region adjacent to the necrotic tissue. No PCNA labeling or nuclear mitotic images were detected in the ventricular myocardium of control subjects. Thus, the observation that diffuse PCNA labeling and myocyte mitotic division are present in hearts with end-stage failure strongly suggests that adult ventricular myocytes are not terminally differentiated cells and that myocyte cellular hyperplasia may constitute a growth reserve mechanism of the diseased heart.


Asunto(s)
Autoantígenos/análisis , División Celular , Núcleo Celular/ultraestructura , Insuficiencia Cardíaca/patología , Ventrículos Cardíacos/patología , Proteínas Nucleares/análisis , Adulto , Anciano , Anciano de 80 o más Años , Antígenos Nucleares , ADN/biosíntesis , Ecocardiografía , Femenino , Feto , Corazón/embriología , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Ventrículos Cardíacos/citología , Hemodinámica , Humanos , Hiperplasia , Masculino , Persona de Mediana Edad , Mitosis , Modelos Biológicos
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