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1.
Cancer Lett ; 78(1-3): 11-7, 1994 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-7514089

RESUMEN

Prostate inhibin peptide (PIP) is a polypeptide synthesized by the prostate gland that is involved in prostatic growth and differentiation. The objective of this study was to evaluate PIP as an immunocytochemical marker for prostatic adenocarcinoma (PCA) by comparing it with PSA and PAP. A total of 71 cases of primary PCA and 5 cases of metastatic PCA were studied. Primary tumors were specially selected to include a disproportionate number of high-grade tumors. The distribution of cases by Gleason score was 2-5, 14 cases; 6-7, 24 cases; and 8-10, 33 cases. Four metastases were to bone (decalcified tissue) and one to soft tissue. All 71 cases of primary PCA stained positively for the three antibodies tested, with none demonstrating obvious superiority, although individual case variability was seen. In one bone metastasis, staining for PSA was negative, with both PAP and PIP giving positive results. All non-prostatic carcinomas tested were negative. These results indicate that PIP is as sensitive and specific an immunohistochemical marker as PSA and PAP in untreated prostate adenocarcinomas. Further, the androgen-independent nature of PIP may give it an advantage over PSA/PAP in tumors exposed to androgen ablating agents.


Asunto(s)
Fosfatasa Ácida/metabolismo , Carcinoma/metabolismo , Péptidos/metabolismo , Antígeno Prostático Específico/metabolismo , Neoplasias de la Próstata/metabolismo , Proteínas de Secreción Prostática , Biomarcadores de Tumor , Humanos , Inmunohistoquímica , Inhibinas , Masculino , Metástasis de la Neoplasia , Proteínas de Neoplasias/metabolismo
2.
Cancer Lett ; 75(1): 1-9, 1993 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-8287377

RESUMEN

We report the occurrence as well as biosynthesis of a pituitary hormone, follicle stimulating hormone (FSH) in human breast. Using immunoperoxidase localization technique, both FSH and beta-FSH were localized in cytoplasm of epithelial cells but not in stromal cells. Immunostaining was more intense in benign and malignant specimens as compared to normal. In vitro radiolabelled precursor experiments with breast tissue explants indicate de novo synthesis of FSH. Human milk had higher concentrations of FSH as compared to serum. In gonads, FSH is involved in the cellular growth, differentiation and function. The presence of higher levels of FSH in benign mammary tumors and breast cancer when compared to normal breast supports the suggestion that FSH might have a role in the process of breast malignant transformation.


Asunto(s)
Enfermedades de la Mama/metabolismo , Neoplasias de la Mama/metabolismo , Hormona Folículo Estimulante/biosíntesis , Mama/metabolismo , Carcinoma in Situ/metabolismo , Citoplasma/química , Epitelio/química , Fibroadenoma/metabolismo , Enfermedad Fibroquística de la Mama/metabolismo , Humanos , Técnicas para Inmunoenzimas , Leche Humana/química , Radioinmunoensayo
3.
Cancer Lett ; 72(1-2): 127-34, 1993 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-8402568

RESUMEN

Using immunocytochemistry, we report the occurrence of a 10.5-kDa inhibin in human breast tissue specimens obtained from normal, fibroadenoma and adenocarcinoma cases. The immunostaining for inhibin was confined to the cytoplasm of the epithelium and myoepithelium cells. Expression of inhibin increased in following order: normal (1+); adenocarcinoma and lobular carcinoma in situ (2+) and fibroadenoma (4+). Breast explants has the ability of denovo biosynthesis of inhibin in vitro. In view of the growth modulating regulatory properties of 10.5 kDa inhibin, our findings are suggestive of the potential role of inhibin in breast pathology.


Asunto(s)
Neoplasias de la Mama/metabolismo , Inhibinas/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Neoplasias de la Mama/patología , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patología , Femenino , Fibroadenoma/metabolismo , Fibroadenoma/patología , Humanos , Técnicas para Inmunoenzimas , Técnicas In Vitro
4.
Crit Rev Biotechnol ; 9(4): 287-304, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2178780

RESUMEN

The ethanol tolerance of yeast and other microorganisms has remained a controversial area despite the many years of study. The complex inhibition mechanism of ethanol and the lack of a universally accepted definition and method to measure ethanol tolerance have been prime reasons for the controversy. A number of factors such as plasma membrane composition, media composition, mode of substrate feeding, osmotic pressure, temperature, intracellular ethanol accumulation, and byproduct formation have been shown to influence the ethanol tolerance of yeast. Media composition was found to have a profound effect upon the ability of a yeast strain to ferment concentrated substrates (high osmotic pressure) and to ferment at higher temperatures. Supplementation with peptone-yeast extract, magnesium, or potassium salts has a significant and positive effect upon overall fermentation rates. An intracellular accumulation of ethanol was observed during the early stages of fermentation. As fermentation proceeds, the intracellular and extracellular ethanol concentrations become similar. In addition, increases in osmotic pressure are associated with increased intracellular accumulation of ethanol. However, it was observed that nutrient limitation, not increased intracellular accumulation of ethanol, is responsible to some extent for the decreases in growth and fermentation activity of yeast cells at higher osmotic pressure and temperature.


Asunto(s)
Etanol/farmacología , Levaduras/efectos de los fármacos , Biotecnología , Membrana Celular/efectos de los fármacos , Tolerancia a Medicamentos/fisiología , Etanol/metabolismo , Presión Osmótica , Saccharomyces/efectos de los fármacos , Saccharomyces/metabolismo , Temperatura , Levaduras/metabolismo
5.
Appl Environ Microbiol ; 54(1): 110-4, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3278685

RESUMEN

An intracellular accumulation of ethanol in Saccharomyces cerevisiae was observed during the early stages of fermentation (3 h). However, after 12 h of fermentation, the intracellular and extracellular ethanol concentrations were similar. Increasing the osmotic pressure of the medium caused an increase in the ratio of intracellular to extracellular ethanol concentrations at 3 h of fermentation. As in the previous case, the intracellular and extracellular ethanol concentrations were similar after 12 h of fermentation. Increasing the osmotic pressure also caused a decrease in yeast cell growth and fermentation activities. However, nutrient supplementation of the medium increased the extent of growth and fermentation, resulting in complete glucose utilization, even though intracellular ethanol concentrations were unaltered. These results suggest that nutrient limitation is a major factor responsible for the decreased growth and fermentation activities observed in yeast cells at higher osmotic pressures.


Asunto(s)
Etanol/metabolismo , Fermentación , Saccharomyces cerevisiae/metabolismo , Glucosa/farmacología , Presión Osmótica
7.
Appl Environ Microbiol ; 50(2): 257-60, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4051481

RESUMEN

The secretion of killer toxins by some strains of yeasts is a phenomenon of significant industrial importance. The activity of a recently discovered Kluyveromyces lactis killer strain against a sensitive Saccharomyces cerevisiae strain was determined on peptone-yeast extract-nutrient agar plates containing as the carbon source glucose, fructose, galactose, maltose, or glycerol at pH 4.5 or 6.5. Enhanced activity (50 to 90% increase) was found at pH 6.5, particularly on the plates containing galactose, maltose, or glycerol, although production of the toxin in liquid medium was not significantly different with either glucose or galactose as the carbon source. Results indicated that the action of the K. lactis toxin was not mediated by catabolite repression in the sensitive strain. Sensitivities of different haploid and polyploid Saccharomyces yeasts to the two different killer yeasts S. cerevisiae (RNA-plasmid-coded toxin) and K. lactis (DNA-plasmid-coded toxin) were tested. Three industrial polyploid yeasts sensitive to the S. cerevisiae killer yeast were resistant to the K. lactis killer yeast. The S. cerevisiae killer strain itself, however, was sensitive to the K. lactis killer yeast.


Asunto(s)
Micotoxinas/biosíntesis , Saccharomyces/crecimiento & desarrollo , Saccharomycetales/metabolismo , Fructosa/metabolismo , Galactosa/metabolismo , Glucosa/metabolismo , Glicerol/metabolismo , Concentración de Iones de Hidrógeno , Maltosa/metabolismo , Micotoxinas/genética , Micotoxinas/farmacología , Fenotipo , Plásmidos , Saccharomycetales/genética , Saccharomycetales/crecimiento & desarrollo
8.
Appl Environ Microbiol ; 47(5): 1164-6, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6378088

RESUMEN

Industrially useful polyploid yeasts such as the brewing yeasts do not possess any auxotrophic genetic markers and hence are not easily amenable to plasmid-mediated DNA transformations. In an attempt to obtain genetic markers, a number of useful Saccharomyces sp. strains and some amylolytic Schwanniomyces sp. strains were tested for their susceptibility to the antibiotic Geneticin G418 , a 2-deoxystreptamine reported to be active against bacteria, yeasts, and plant and animal cells. All of the Saccharomyces sp. strains, including the brewing strains, were found to be susceptible to G418 in the concentration range of 150 to 500 micrograms/ml. Of the three Schwanniomyces species investigated, only Schwanniomyces castellii (strain 1402) was found to be resistant to G418 at concentrations up to 1 mg/ml. Resistance was exhibited both in liquid media and on glycerol-peptone-yeast extract agar plates. This finding is interesting in view of the possibility of using this strain as a DNA donor for transformations aimed at introducing the amylolytic capability into brewing yeasts.


Asunto(s)
Antibacterianos/farmacología , Ascomicetos/efectos de los fármacos , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces/efectos de los fármacos , Saccharomycetales/efectos de los fármacos , Farmacorresistencia Microbiana , Gentamicinas/farmacología , Pruebas de Sensibilidad Microbiana , Saccharomyces/crecimiento & desarrollo , Saccharomyces cerevisiae/crecimiento & desarrollo , Saccharomycetales/crecimiento & desarrollo
9.
Crit Rev Food Sci Nutr ; 14(2): 153-99, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7011686

RESUMEN

The review attempts to deal with the state of the art of UHT milk processing, economics, packaging, and quality maintenance. Various methods of processing are covered in detail. A sample system was considered for material and energy balances. A major factor in UHT milk technology is the economics of the process adopted. This is considered for the major processes currently in operation. Packaging and handling of UHT milk is of vital importance for the maintenance of the quality and flavor of the milk. A review of the different packaging systems describes the advantages and disadvantages of each one. The review is divided into the following sections: (1) major direct and indirect processes, (2) energy requirements and economics, (3) material and energy balances for fluid milk processing, storage, and distribution systems, (4) aseptic packaging, and (5) quality effects.


Asunto(s)
Manipulación de Alimentos/métodos , Leche/normas , Animales , Asepsia/métodos , Bovinos , Comercio , Manipulación de Alimentos/economía , Manipulación de Alimentos/instrumentación , Conservación de Alimentos , Industria de Procesamiento de Alimentos/economía , Calor , América del Norte , Esterilización , Transportes
10.
CRC Crit Rev Microbiol ; 5(1): 39-66, 1976 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-793775

RESUMEN

This review discusses the currect state of the art on the subject of emulsifiers, particularly those of biological origins. The basic principles involved in the mode of action of emulsifier molecules are reviewed. Current ideas on the classification, physicochemical properties, stability, and rheological properties of emulsions are discussed. The literature review on bio-emulsifiers emphasizes those of microbial origins and their application in industry. Some of the more common methods for the study of emulsion properties are also outlined.


Asunto(s)
Bacterias , Emulsiones , Hongos , Plantas , Animales , Bacterias/metabolismo , Sangre , Electrólitos , Emulsiones/análisis , Hongos/metabolismo , Molleja de las Aves , Corazón , Sustancias Macromoleculares , Carne , Métodos , Leche , Músculos , Proteínas de Plantas , Aves de Corral , Proteínas , Surfactantes Pulmonares , Reología , Piel , Tensoactivos , Viscosidad
11.
J Bacteriol ; 117(2): 675-80, 1974 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-4590481

RESUMEN

Ribonucleic acid (RNA) isolated from Escherichia coli W3350 (F(-), argE(+)C(+)B(+)H(+)), in the absence of l-arginine, hybridizes with the separated leftward (l) and rightward (r) transcribing strands of the arginine transducing phage hphi80dargE(+)C(+)B(+)H(+)ppc(+)imm(lambdacI857) deoxyribonucleic acid (DNA) with a ratio of 30:70, respectively. In the presence of l-arginine and its intermediates, l-ornithine and l-citrulline, RNA transcriptions from both the strands of the argECBH cluster were repressed. The derepressed RNA, when hybridized with the separated strands of hphi80dargEC-I imm(lambda) phage DNA (the arginine genes are inversely inserted in this phage), which has a deletion in gene E and extends to gene C of the argECBH cluster, showed no leftward transcription, whereas the rightward transcription was reduced to about 40% of that when the DNA carrying the entire ECBH cluster was used for hybridization. The hybridization results thus demonstrate that (i) the regulation of the argECBH gene cluster in E. coli is under transcriptional control, (ii) the orientation of transcription is divergent, (iii) E gene transcribes anticlockwise, whereas the rest of the genes, C, B, and H, transcribe clockwise, and (iv) the position of the promoter(s) and operator(s) is located between the E and C genes of the argECBH cluster.


Asunto(s)
Arginina/biosíntesis , Escherichia coli/metabolismo , Genes , Transcripción Genética , Arginina/farmacología , Centrifugación por Gradiente de Densidad , Mapeo Cromosómico , Citrulina/farmacología , Colifagos , ADN Viral , Lisogenia , Mutación , Hibridación de Ácido Nucleico , Ornitina/farmacología , Radioisótopos de Fósforo , ARN Bacteriano/biosíntesis , ARN Bacteriano/aislamiento & purificación , Estereoisomerismo , Transducción Genética , Tritio
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