Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Oncoimmunology ; 4(7): e1017702, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26140248

RESUMEN

Adenoviruses are excellent immunotherapeutic agents with a unique ability to prime and boost immune responses. Recombinant adenoviruses cause immunogenic cancer cell death and subsequent release of tumor antigens for antigen presenting cells, resulting in the priming of potent tumor-specific immunity. This effect may be further enhanced by immune-stimulating transgenes expressed by the virus. We report a case of a 38-year-old female with Stage 3 metastatic micropapillary serous carcinoma of the ovary. She was treated in a Phase I study with a granulocyte-macrophage colony stimulating factor (GMCSF)-expressing oncolytic adenovirus, Ad5/3-D24-GMCSF (ONCOS-102). The treatment resulted in progressive infiltration of CD8+ lymphocytes into the tumor and concomitant systemic induction of several tumor-specific CD8+ T-cell populations. The patient was alive at the latest follow up more than 20 months after initiation of the study.

2.
Br J Cancer ; 104(4): 599-604, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21304526

RESUMEN

BACKGROUND: Hypertension (HTN) is a common toxicity of anti-VEGF (vascular endothelial growth factor) antibody treatment. It may be a marker of VEGF signalling pathway inhibition and therefore represent a cancer biomarker in metastatic colorectal cancer (mCRC) patients treated with chemotherapy and bevacizumab. METHODS: A total of 101 consecutive patients with mCRC were treated with standard chemotherapy combined with bevacizumab at dose of 2.5 mg kg(-1) per week in a single centre. The median follow-up time of the patients alive was 64 months. Blood pressure was measured before each bevacizumab infusion, and HTN was graded according to common toxicity criteria for adverse events version 3.0. RESULTS: Overall, 57 patients (56%) developed ≥grade 1 HTN (median blood pressure 168/97 mm Hg), whereas 44 (44%) remained normotensive when treated with bevacizumab-containing chemotherapy regimen. Overall response rate was higher among patients with HTN (30 vs 20%; P=0.025). Hypertension was associated with improved progression-free survival (10.5 vs 5.3 months; P=0.008) and overall survival (25.8 vs 11.7 months; P<0.001), and development of HTN within 3 months had an independent, prognostic influence in a multivariate landmark survival analysis together with other known mCRC prognostic factors (P=0.007). There was no association between HTN and development of thromboembolic complications. CONCLUSION: Hypertension may predict outcome of bevacizumab-containing chemotherapy in mCRC. These data require confirmation in prospective studies including pharmacodynamic and pharmacokinetic analyses.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma/tratamiento farmacológico , Carcinoma/mortalidad , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/mortalidad , Hipertensión/epidemiología , Adulto , Anciano , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bevacizumab , Carcinoma/epidemiología , Carcinoma/patología , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/patología , Femenino , Humanos , Hipertensión/inducido químicamente , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
3.
Ann Oncol ; 21(5): 968-73, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19819914

RESUMEN

BACKGROUND: Alternating administration of docetaxel and gemcitabine might result in improved time-to-treatment failure (TTF) and fewer adverse events compared with single-agent docetaxel as treatment of advanced breast cancer. PATIENTS AND METHODS: Women diagnosed with advanced breast cancer were randomly allocated to receive 3-weekly docetaxel (group D) or 3-weekly docetaxel alternating with 3-weekly gemcitabine (group D/G) until treatment failure as first-line chemotherapy. The primary end point was TTF. RESULTS: Two hundred and thirty-seven subjects were assigned to treatment (group D, 115; group D/G, 122). The median TTF was 5.6 and 6.2 months in groups D and D/G, respectively (hazard ratio 0.85, 95% confidence interval 0.63-1.16; P = 0.31). There was no significant difference in time-to-disease progression, survival, and response rate between the groups. When adverse events were evaluated for the worst toxicity encountered during treatment, there was little difference between the groups, but when they were assessed per cycle, alternating treatment was associated with fewer severe (grade 3 or 4) adverse effects (P = 0.013), and the difference was highly significant for cycles when gemcitabine was administered in group D/G (P < 0.001). CONCLUSION: The alternating regimen was associated with a similar TTF as single-agent docetaxel but with fewer adverse effects during gemcitabine cycles.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Lobular/tratamiento farmacológico , Adulto , Anciano , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/secundario , Carcinoma Lobular/metabolismo , Carcinoma Lobular/secundario , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Docetaxel , Femenino , Humanos , Técnicas para Inmunoenzimas , Persona de Mediana Edad , Invasividad Neoplásica , Metástasis de la Neoplasia , Estudios Prospectivos , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Tasa de Supervivencia , Taxoides/administración & dosificación , Resultado del Tratamiento , Gemcitabina
6.
Radiat Prot Dosimetry ; 123(4): 537-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17166878

RESUMEN

Exposure of workers to radiofrequency fields was assessed in two medium-sized antenna towers. Towers had transmitting antennas from different networks, e.g. mobile phone networks, radio and digital TV sub-stations and amateur radio. The levels of radiofrequency fields were measured close to the ladders of the towers. All measured values were below ICNIRP occupational reference levels.


Asunto(s)
Teléfono Celular , Campos Electromagnéticos , Exposición Profesional , Ondas de Radio , Televisión , Finlandia , Humanos
7.
J AOAC Int ; 83(6): 1357-65, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11128138

RESUMEN

A collaborative study on total aerobic bacterial count was conducted to validate the Hygicult TPC dipslide against contact plates and swabbing, using stainless-steel surfaces artificially contaminated with different microbes at various levels. Twelve laboratories took part in the validation procedure. The total number of collaborative samples was 108. The microbial level in each sample was assessed in triplicate using the 3 above-mentioned methods under 3 different incubation conditions (at 25 +/- 1 degrees C for 48 and 72 h and at 30 +/- 1 degrees C for 48 h). Surface sampling methods detached 25-30% at the lowest (theoretical yield, 1.4 cfu/cm2), 18-20% at the middle (theoretical yield, 10.7 cfu/cm2), and 16-21% at the highest (theoretical yield, 43.6 cfu/cm2) levels of microbes from the test surfaces. The percentage of acceptable results after removing outliers was 89%. Repeatability standard deviations ranged from 27.2 to 74.6% and reproducibility standard deviations ranged from 42.1 to 97.5%. There were no significant differences between results obtained at different incubation temperatures (25 and 30 degrees C) or incubation times (48 and 72 h) for all 3 methods. The Hygicult TPC dipslide, contact plate, and swabbing methods gave similar results at all 3 microbial levels tested: 0.35-0.43 cfu/cm2 at the lowest level, 1.9-2.2 cfu/cm2 at the middle level, and 7.1-9.1 cfu/cm2 at the highest level.


Asunto(s)
Microbiología de Alimentos/normas , Algoritmos , Bacterias Aerobias , Medios de Cultivo , Finlandia , Indicadores y Reactivos , Temperatura
8.
J Invest Dermatol ; 115(2): 286-91, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10951248

RESUMEN

We used type I collagen gel cultures to compare the growth requirements of melanocytes and dermal nevus cells. Melanocytes but not nevus cells undergo apoptosis in collagen unless supplied with growth stimulators such as fibroblast growth factor 2. To characterize the mechanism of melanocyte apoptosis in collagen, we tested the effects of transforming growth factor beta1, known to be functionally active in the skin. When picomolar amounts of transforming growth factor beta1 were added to normal melanocytes grown in type I collagen gel, their apoptosis was dramatically accelerated. In contrast, the apoptotic rate of nevus cells and melanoma cells grown under similar conditions was not affected by transforming growth factor beta1. The increased apoptosis of normal melanocytes was effectively counteracted by addition of either neutralizing transforming growth factor beta1 antibodies or fibroblast growth factor 2 to the collagen gel. Interestingly, the background apoptosis of normal melanocytes was also inhibited by transforming growth factor beta1 antibodies. By Western blotting we detected transforming growth factor beta-like immunoreactivity in melanocyte, nevus cell, and melanoma cell lysates. A sensitive bioassay confirmed that their medium contained considerable amounts of heat-activatable growth inhibitory activity that could partly be neutralized by transforming growth factor beta1 antibodies. It is evident that apoptosis of melanocytes grown in type I collagen gel can be mediated by both endogenous and exogenous transforming growth factor beta. We suggest that the balance between inhibitory growth factors such as transforming growth factor beta and stimulatory growth factors like fibroblast growth factor 2 has the potential to regulate the growth, localization, and survival of normal melanocytes also in vivo. The resistance of nevus cells to transforming-growth-factor-beta-mediated apoptosis may facilitate their ability to grow in the dermal compartment of the skin.


Asunto(s)
Apoptosis/efectos de los fármacos , Colágeno/farmacología , Melanocitos/efectos de los fármacos , Melanocitos/fisiología , Nevo/fisiopatología , Factor de Crecimiento Transformador beta/farmacología , Anticuerpos/farmacología , División Celular/efectos de los fármacos , Células Cultivadas , Medios de Cultivo/farmacología , Geles , Humanos , Melanocitos/metabolismo , Nevo/patología , Valores de Referencia , Factor de Crecimiento Transformador beta/inmunología , Factor de Crecimiento Transformador beta/metabolismo
9.
J Invest Dermatol ; 113(1): 111-6, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10417628

RESUMEN

Melanocytes, the pigment forming cells of the skin, form an almost nonproliferating cell population located to the lowermost part of the epidermis. Normally melanocytes are not found higher in the epidermis or in the dermis. Nevi consist of melanocytes with altered growth characteristics and localization. The common pigmented nevus, a benign skin lesion, develops when melanocytes proliferate in the dermo-epidermal junction or in the dermis. Here we report growth characteristics of in vitro cultured normal human melanocytes and dermal nevus-derived melanocytes. As previously reported, nevus cells have a moderate to high FGF-2 expression level. Here we demonstrate that dermal nevus cells are able to survive in three-dimensional type 1 collagen culture, while normal human melanocytes rapidly undergo apoptosis. Melanocytes also, however, survive in collagen cultures in the presence of exogenous FGF-2. The survival of nevus cells in collagen is suppressed by protamine, an inhibitor of FGF-mediated cell stimulation. The in vivo growth environment of dermal nevus cells consists largely of type I and type III collagens. The results suggest that FGF-2 expression by nevus cells allows them to adapt to grow in the dermis. FGF-2 obviously has importance as a melanocyte survival factor and probably also in the development of malignant melanoma.


Asunto(s)
Apoptosis/efectos de los fármacos , Colágeno/farmacología , Factor 2 de Crecimiento de Fibroblastos/genética , Melanocitos/efectos de los fármacos , Nevo/genética , Neoplasias Cutáneas/genética , Adulto , Técnicas de Cultivo de Célula/métodos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Factor 2 de Crecimiento de Fibroblastos/farmacología , Fibronectinas/farmacología , Geles , Expresión Génica , Regulación de la Expresión Génica , Humanos , Laminina/farmacología , Melanocitos/citología , Melanocitos/metabolismo , Nevo/patología , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , Receptores de Factores de Crecimiento de Fibroblastos/genética , Neoplasias Cutáneas/patología
10.
Dig Dis Sci ; 43(7): 1507-12, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9690387

RESUMEN

Immediate repair of the gastrointestinal epithelium after superficial injury is called restitution. It is based on the migration of the surviving mucoid neck cells over the area of injury. The involvement of growth factors in the process has been recently documented. They are known to enhance the process (ie, EGF, FGF, TGF-beta) and to activate the basolateral Na+-H+-antiport (EGF). They may exert their effect by activating intracellular tyrosine kinases or by inducing chemotaxis. Yet, their precise mechanism of action in the process is unknown. The aim of the present study was to investigate the effect of modulation of the signal transduction pathway on the occurrence of proliferative mucoid neck and foveolar cells in guinea pig gastric epithelium. Therefore guinea pig gastric epithelium was mounted in Ussing chambers in vitro and perfused 4 hr after superficial injury with 1.25 M NaCl. The potential difference over the epithelium and tissue resistance were recorded simultaneously. The tissue was exposed either to cycloheximide, genistein, or to 4-phorbol myristate 13-acetate (PMA) during the 4-hr recovery, and the expression of proliferative cells was assessed by staining the tissue for proliferative cells (Ki-67). The mean proliferative index of tissues subjected to NaCl injury was significantly higher than that of uninjured control tissues after 4 hr of restitution. Inhibition of the signaling pathway with genistein decreased the proliferative index significantly, while its stimulation with phorbol myristate increased it. Both electrophysiologic and morphologic restitution were sensitive to genistein, but not to PMA or cycloheximide. Superficial epithelial injury results in a significantly increased occurrence of proliferative cells in isolated guinea pig gastric epithelium. This endogenous activation of the tissue is sensitive to inhibition by tyrosine kinases and to stimulation by protein kinases. Electrophysiologic and morphologic recovery are also affected by the modulation of the signaling pathway. This suggests that it is involved in the immediate repair process.


Asunto(s)
Mucosa Gástrica/lesiones , Cicatrización de Heridas/fisiología , Animales , Carcinógenos/farmacología , División Celular , Cicloheximida/farmacología , Inhibidores Enzimáticos/farmacología , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/fisiología , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/patología , Mucosa Gástrica/fisiología , Genisteína/farmacología , Cobayas , Antígeno Ki-67/metabolismo , Inhibidores de la Síntesis de la Proteína/farmacología , Transducción de Señal/efectos de los fármacos , Cloruro de Sodio , Acetato de Tetradecanoilforbol/farmacología
11.
Exp Cell Res ; 228(2): 306-12, 1996 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8912724

RESUMEN

Tera-2 is a human teratocarcinoma cell line, which is induced to differentiate into neuronal direction by retinoic acid. Once differentiated, the cells form an almost nondividing population that can be maintained for weeks under conventional culture conditions. If differentiation by retinoic acid is induced while the cells are growing on type I collagen or if the already-differentiated cells are transferred onto collagen, they survive only a few days unless the cultures are repeatedly supplied with FGF-2. Lack of this growth factor induces programmed cell death (apoptosis) detectable after 24-48 h, as marked by DNA cleavage and nuclear fragmentation. The undifferentiated stem cells survive and proliferate readily on collagen without addition of FGF-2. Tera-2 cells express two members of the FGF family, FGF-2 and FGF-4. The expression of both FGFs is turned off during differentiation on collagen substratum, whereas when cultivated on plain tissue culture dish, the expression of only FGF-4 becomes undetectable. The results indicate that signaling through cell surface FGF receptors is vital for the cells, and differentiation on collagen substratum results in complete extinction of the autocrine stimulatory loop. In vivo, such induction of growth factor dependency upon differentiation would result in apoptotic death of those cells which fail to find adequate conditions for continuing FGF stimulation.


Asunto(s)
Apoptosis/efectos de los fármacos , Diferenciación Celular , Colágeno , Factor 2 de Crecimiento de Fibroblastos/biosíntesis , Factor 2 de Crecimiento de Fibroblastos/farmacología , Transcripción Genética , Línea Celular , Núcleo Celular/efectos de los fármacos , Núcleo Celular/ultraestructura , Factor 4 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/biosíntesis , Humanos , Cinética , Neuronas/citología , Neuronas/efectos de los fármacos , Proteínas Proto-Oncogénicas/biosíntesis , ARN Mensajero/biosíntesis , Proteínas Recombinantes/farmacología , Teratocarcinoma , Factores de Tiempo , Tretinoina/farmacología , Células Tumorales Cultivadas
12.
Differentiation ; 59(3): 193-9, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7589903

RESUMEN

Tera 2 human embryonal carcinoma cells proliferate rapidly in culture but are capable of differentiating into quiescent cells with neuronal features. We have characterized the effects of exogenous and endogenous fibroblast growth factors on the proliferation of differentiating Tera 2 cells. Exogenous basic fibroblast growth factor (bFGF) stimulated DNA synthesis and induced the proliferation-associated antigen Ki 67 in differentiated Tera 2 cells. Heparin-binding growth factors isolated from the undifferentiated cells excerted a similar stimulatory effect on their differentiated derivatives. The functional potential of these endogenous growth factors was further demonstrated by their ability to stimulate plasminogen activator production by capillary endothelial cells. A major part of the growth promoting activity was removed by absorption with immobilized bFGF antibodies. bFGF was also detected in Tera 2 cells by immunoblotting. The production of heparin-binding growth-promoting activity decreased during differentiation. The results demonstrate a potential role for heparin-binding growth factors in the autocrine or paracrine growth regulation of teratocarcinoma cells.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/fisiología , Células Madre Neoplásicas/citología , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Células Cultivadas , Células Madre de Carcinoma Embrionario , Factor 2 de Crecimiento de Fibroblastos/farmacología , Heparina/metabolismo , Humanos , Tretinoina/farmacología
13.
J AOAC Int ; 77(2): 425-30, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8199479

RESUMEN

A collaborative study was conducted of a spectrophotometric method for determination of nitrate after cadmium reduction to nitrite in baby foods containing meat. Thirty-one municipal and 2 industrial food laboratories participated in the study. The study design involved 2 baby food matrices. Samples of both matrices were prepared at 3 concentration levels between 52 and 309 mg NaNO3/kg as blind duplicates. A blank without added nitrate was also included. The outlier percentage of the results was very low (4.3%). It was typical for the method that recoveries were slightly > 100%. Recoveries for baby foods varied between 113.3 and 116.9%, and were acceptable for control purposes. The relative standard deviations for repeatability were 5.0-18.1%. The relative standard deviations for reproducibility were 8.3-21.6%. Three collaborators also evaluated liquid chromatographic technique for nitrate determinations. These preliminary results are presented but are not analyzed statistically. The spectrophotometric method was adopted first action by AOAC INTERNATIONAL.


Asunto(s)
Alimentos Infantiles/análisis , Nitratos/análisis , Análisis de los Alimentos , Humanos , Recién Nacido , Carne , Nitritos/análisis , Espectrofotometría/métodos
14.
Dev Biol ; 161(1): 141-53, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8293870

RESUMEN

Rapidly growing human teratocarcinoma cells (Tera-2) can be induced to differentiate into quiescent, nontumorigenic cells expressing neuronal markers. To more closely mimic the in vivo conditions for tumor growth, we grew Tera-2 cells in three-dimensional collagen gel cultures. The undifferentiated cells proliferated in the gel, forming tight colonies. Addition of soluble fibroblast growth factor 1 or 2 (FGF1 or FGF2) into the gel resulted in scattering of single cells throughout the collagen gel. In a FGF gradient the cells moved rapidly toward a higher concentration. On the contrary, cells first differentiated for 8 days in retinoic acid died within a few days after transfer into the collagen gel. Alternatively, if retinoic acid was included in the collagen gel, the proliferating undifferentiated cells died after 4-5 days in the gel. This differentiation-related cell death was completely opposed by including FGF in the collagen gel. When placed in the FGF gradient, the fully differentiated cells survived at the areas of higher FGF concentration, but no more migrated. The survival of retinoic acid-differentiated Tera-2 cells in collagen was also mediated by direct contact with glioma cells or the heparan sulfate-rich portion of glioma or endothelial cell matrix. These effects on differentiated cells were sensitive to inhibition by affinity-purified anti-FGF2 IgG. Thus, FGF has the potential to act as a migration-inducing factor either in solution or, more likely, in vivo, as an immobilized, matrix-bound growth factor directing the movement of responsive cells. The development of differentiation-associated FGF dependency allows survival of the cells only at places where they are in close contact with either FGF-synthesizing cells or FGF-rich extracellular structures such as basement membranes.


Asunto(s)
Factor de Crecimiento Epidérmico/farmacología , Células Madre Neoplásicas/citología , Teratocarcinoma/patología , Tretinoina/farmacología , Animales , Bovinos , Comunicación Celular , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Madre de Carcinoma Embrionario , Factor de Crecimiento Epidérmico/genética , Humanos , Células Madre Neoplásicas/efectos de los fármacos , ARN Mensajero/análisis , Células Tumorales Cultivadas
15.
J AOAC Int ; 76(3): 674-81, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8318863

RESUMEN

A BCR1 collaborative study was conducted with a microbiological screening method based on the combined use of the direct epifluorescent filter technique (DEFT) and the conventional aerobic plate count method (APC) for detection of irradiation of spices and herbs. Collaborative samples of whole allspice, whole and powdered black peppers, whole white pepper, paprika powder, cut basil, cut marjoram, and crushed cardamom irradiated with doses of 0, 5, and 10 kGy were analyzed by 8 laboratories. The total number of the collaborative samples, with arbitrarily labeled codes, was 192. The percentage of acceptable results was 95.5%. The identification of irradiated from nonirradiated spices and herbs was analyzed statistically by using explorative techniques. The average values of the differences between DEFT and APC in samples irradiated with doses of 5 and 10 kGy were 5.1 and 6.1 logarithmic units, respectively. The differences between DEFT and APC generally increased to at least 3.5 logarithmic units, whereas the difference in the case of unirradiated spices was insignificant. However, conclusive evidence of irradiation relies on the knowledge that the sample was not fumigated or heat treated. The reproducibility relative standard deviations for the differences were 12.3, 19.9, and 20.7% with the doses of 10 and 5 kGy and for unirradiated samples, respectively, indicating acceptable variabilities among laboratories.


Asunto(s)
Irradiación de Alimentos , Magnoliopsida/efectos de la radiación , Especias/efectos de la radiación , Bioensayo , Unión Europea , Filtración , Fluorescencia , Indicadores y Reactivos , Magnoliopsida/química , Especias/análisis
16.
Br J Addict ; 87(5): 755-66, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1591526

RESUMEN

The drinking history of a middle-aged male was analyzed statistically on the basis of eight and a half years of notes on the number of drinks consumed per day. During the period his average number of drinks per drinking day increased from about 7 in 1974 to a peak of about 16 in 1980 while the number of abstinent days varied between 23% and 54% with no clear trend. These figures are of the same magnitude as published reports on drinking among alcoholics. Time-series models of intake or drinking frequency could not describe adequately the time-structure of annual or monthly consumption. Occurrence of drinking was analyzed as a random series of events. The time-structure of the series was highly irregular and deviated greatly from the Poisson hypothesis which assumes that each day has an equal probability of becoming a drinking day independently of previous days. Instead, drinking days were clustered into sprees with an average length of 7 days, high variance and a very skew distribution, separated by abstinence periods with an average length of 4 days and a similarly shaped distribution. The entire history could be partitioned into 286 alternating drinking and abstinence intervals, one day intervals included. The drinking rhythm was very stable: no significant trends in the lengths of either type of interval could be found. The main findings are the surprising stability of the drinking rhythm, its independence of the growing amounts consumed, and the independently varying abstinence interval lengths. Even in the absence of reporting and memory bias, such a pattern of drinking may produce very inaccurate recall of the actual long-term alcohol intake, if the recall period is short. The results suggest that periods shorter than one month should be avoided when asking questions about alcohol intake, for example, in research on the effects of treatment on alcoholism or alcohol intake on health.


Asunto(s)
Consumo de Bebidas Alcohólicas , Adaptación Psicológica , Consumo de Bebidas Alcohólicas/psicología , Humanos , Acontecimientos que Cambian la Vida , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
17.
Acta Vet Scand ; 33(1): 27-32, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1598855

RESUMEN

The effect of NaNO2 and NaCl on the growth of 24 lactic acid bacteria strains isolated from vacuum-packed cooked ring sausages were examined by analyzing different growth parameters with Bioscreen. NaNO2 had a very limited effect on the growth of lactic acid bacteria at 50 and 100 mg/l but at 400 mg/l a more pronounced inhibitory effect was found. Bacterial growth was enhanced by 1-2% (w/v) of added NaCl, while NaCl concentrations above 3% (w/v) had a clear inhibitory effect. Leuconostoc isolates seemed to be more sensitive to sodium nitrite and sodium chloride than homofermentative lactobacilli strains. Among homofermentative lactobacilli, the strains resembling Lactobacillus curvatus were more sensitive to NaCl than those resembling Lactobacillus sake.


Asunto(s)
Microbiología de Alimentos , Lactobacillus/efectos de los fármacos , Productos de la Carne/microbiología , Cloruro de Sodio/farmacología , Nitrito de Sodio/farmacología , Animales , Lactobacillus/crecimiento & desarrollo
18.
Cell Regul ; 2(4): 285-97, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1905574

RESUMEN

Human Tera 2 embryonal carcinoma cells switch gradually from rapidly growing undifferentiated cells to almost nonproliferating cells during retinoic acid (RA)-induced neuronal differentiation. This process is associated with the increased expression of type 1 plasminogen activator inhibitor (PAI 1) mRNA, and the secreted inhibitor is immobilized to the pericellular area. Furthermore, the differentiation is accompanied by a decrease in the amount of both the secreted tissue-type PA (tPA) and the mainly cell-associated urokinase-type PA (uPA) activity. In RA-differentiated cells, uPA becomes localized at the vinculin-rich cell-substratum adhesion sites. Fibroblast growth factor activity has been associated with various events during embryonal growth and with the regulation of proteolytic enzymes. A short-term treatment of the undifferentiated Tera 2 cells with basic fibroblast growth factor (bFGF) increases uPA mRNA levels and the cell-associated uPA activity, whereas the secretory tPA activity decreases. bFGF induces PAI 1 mRNA expression in the undifferentiated cells, but unlike PAI 1 protein after RA-treatment, the inhibitor does not accumulate around the cells but is released in the medium. A similar exposure to bFGF has less effect on the RA-differentiated Tera 2 cells. Under these conditions bFGF treatment leads to an increase in the amounts of PAI 1 and uPA mRNAs, but no changes in the localization of these components can be seen. Differentiation of human embryonal carcinoma cells is thus connected with an altered response to bFGF.


Asunto(s)
Factores de Crecimiento de Fibroblastos/farmacología , Activadores Plasminogénicos/metabolismo , Tretinoina/farmacología , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Northern Blotting , Diferenciación Celular/efectos de los fármacos , Proteínas del Citoesqueleto/metabolismo , Electroforesis en Gel de Poliacrilamida , Fibrinólisis , Humanos , Inmunohistoquímica , Activadores Plasminogénicos/antagonistas & inhibidores , Activadores Plasminogénicos/genética , Inactivadores Plasminogénicos/metabolismo , ARN Mensajero/biosíntesis , Teratoma , Activador de Tejido Plasminógeno/metabolismo , Células Tumorales Cultivadas , Activador de Plasminógeno de Tipo Uroquinasa/antagonistas & inhibidores , Activador de Plasminógeno de Tipo Uroquinasa/genética , Vinculina
19.
Acta Vet Scand ; 32(1): 123-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1950845

RESUMEN

The accuracy of portable pH meters and the nitrazine yellow method was compared with the reference method by determining the pH of 74 beef and 96 pork muscles. The pH was measured directly from the muscle. The results showed statistically significant differences (p less than 0.001) between the different electrometric combinations. Combinations of portable pH meters with puncture electrodes gave systematically higher pH values than the reference method. These differences were not very large but they may be of practical significance. The use of a piercing cover on the electrode to help the insertion of the electrode into the meat is not recommended, since it may cause a rise in pH values. Electrometric methods were found to be more precise than the nitrazine yellow method. On the basis of these findings there still is a need of further harmonization of the methods used for pH measurement of meat.


Asunto(s)
Carne/análisis , Músculos/química , Animales , Compuestos Azo , Bovinos , Electrodos/veterinaria , Concentración de Iones de Hidrógeno , Indicadores y Reactivos , Carne/normas , Porcinos
20.
Int J Food Microbiol ; 10(3-4): 245-53, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2397156

RESUMEN

Lactic acid production and pH changes of 206 vacuum-packed cooked ring sausages stored at 2, 4 and 12 degrees C from 21 different production runs were monitored as a function of time and of microbial growth. The total lactic acid concentrations and pH values were first at a constant level, starting to increase sharply after the lactobacilli count reached about 5 x 10(7) or 6 x 10(7) cfu/g, respectively. The lactic acid and pH changes as a function of the lactobacilli count were similar at 4 and 12 degrees C. The sharp increase at high lactobacilli counts was observed in both L-lactic acid and D-lactic acid. The variation was lesser and the increase greater in D-lactic acid formation than in L-lactic acid. Above a level of 3-4 mg lactic acid/g most of the samples were deemed unfit. The pH started to decrease from a level of approx. 6.3; below 5.8-5.9 the samples were deemed unfit. The lowest pH value observed was 4.58. Both a high lactic acid content and a low pH indicated that the sausage was spoiled. These changes, however, took place at later stages of storage, and do not give information about the early phase of spoilage.


Asunto(s)
Microbiología de Alimentos , Conservación de Alimentos , Lactatos/análisis , Lactobacillaceae/crecimiento & desarrollo , Productos de la Carne/análisis , Carne/análisis , Animales , Recuento de Colonia Microbiana , Medios de Cultivo , Concentración de Iones de Hidrógeno , Ácido Láctico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...