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F Saez

Publications and source records attributed to F Saez.

14 recordsLinked to original sources
PubMed2004

Nuclear oxysterol receptors, LXRs, are involved in the maintenance of mouse caput epididymidis structure and functions.

In this study we looked at the epididymides and spermatozoa of mice knocked-out for nuclear oxysterol receptors (LXR). We have shown that LXR-deficient mice exhibited upon ageing a severe disruption of their caput epididymides associated with abnormal accumulation of neutral lipids. The epididymis defaults were correlated with sperm head fragility and infertility. In agreement with the observed caput defect in transgenic animals in which both LXRalpha and LXRbeta isoforms were disrupted, we have shown here that both receptors are expressed in caput and cauda epididymides regions. LXRbeta was predominantly expressed throughout the mouse epididymis while the expression of LXRalpha was weaker. In addition, the expression of selected genes that can be considered as markers of adult epididymis function was monitored via Northern blots in the different single and double LXR-deficient backgrounds. Altogether, the data presented here suggest that LXR receptors are important actors in epididymis function.

Animals↗
PubMed2001

Ethanol production from lignocellulosic byproducts of olive oil extraction.

The recent implementation of a new two-step centrifugation process for extracting olive oil in Spain has substantially reduced water consumption, thereby eliminating oil mill wastewater. However, a new high sugar content residue is still generated. In this work the two fractions present in the residue (olive pulp and fragmented stones) were assayed as substrate for ethanol production by the simultaneous saccharification and fermentation (SSF) process. Pretreatment of fragmented olive stones by sulfuric acid-catalyzed steam explosion was the most effective treatment for increasing enzymatic digestibility; however, a pretreatment step was not necessary to bioconvert the olive pulp into ethanol. The olive pulp and fragmented olive stones were tested by the SSF process using a fed-batch procedure. By adding the pulp three times at 24-h intervals, 76% of the theoretical SSF yield was obtained. Experiments with fed-batch pretreated olive stones provided SSF yields significantly lower than those obtained at standard SSF procedure. The preferred SSF conditions to obtain ethanol from olives stones (61% of theoretical yield) were 10% substrate and addition of cellulases at 15 filter paper units/g of substrate.

Biodegradation, Environmental↗
PubMed2000

Endometrial carcinoma: assessment of myometrial invasion with plain and gadolinium-enhanced MR imaging.

The purpose of this study was to determine the accuracy of magnetic resonance imaging (MRI) for evaluating the depth of myometrial invasion, potential sources of pitfalls, and the usefulness of contrast-enhanced series. Eighty-five patients with a pathologic diagnosis of endometrial carcinoma underwent preoperative MRI (plain and contrast-enhanced). Grade of myometrial invasion, presence of junctional zone (JZ), fibromyomas, and tumoral thickness were evaluated by two groups of radiologists blinded to pathologic results. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MRI in determining the depth of myometrial invasion were evaluated. The sensitivity/specificity for plain MR was 64.1-64.1/93.5-100 for both observers. Assessing deep myometrial invasion, sensitivity, and NPV improved significantly (P = 0.002, P = 0.003 for both observers) when comparing plain and whole study series. Tumoral thickness (P = 0.16, P = 0.13, for the two observers) and presence or absence of JZ (P = 0.41, P = 0.14) did not influence myometrial invasion assessment. Gadolinium-enhanced series improve the assessment of deep myometrial invasion in endometrial carcinoma. J. Magn. Reson. Imaging 2000;12:460-466.

Aged↗
PubMed2000

Prostasomes inhibit the NADPH oxidase activity of human neutrophils.

Prostasomes are particular lipid vesicles secreted by the prostate in human semen and involved in several physiological functions such as the improvement of sperm motility or immunomodulation. We have previously shown that they reduced the overall reactive oxygen species (ROS) production of seminal polymorphonuclear neutrophils (PMN). The present study was conducted to define the mechanism by which prostasomes inhibit the ROS production of blood and seminal PMN. The luminol chemiluminescence measuring total ROS production of blood PMN stimulated by either a phorbol ester (PMA) or a chemoattractant peptide, formyl-Met-Leu-Phe (fMLP) was significantly inhibited by prostasomes. The NADPH oxidase activity of the PMN was measured by 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1, 2-a]pyrazin-3-one (MCLA) chemiluminescence. Prostasomes inhibited the NADPH oxidase activity of blood or seminal PMN and increased the lag-phase of the enzyme after PMA stimulation. Prostasomes also inhibited significantly the NADPH oxidase activity of fMLP stimulated blood PMN, but the inhibition was not significant for seminal PMN. The lipid composition of blood PMN was analysed and compared to the lipid composition of prostasomes. This showed that prostasomes had a high cholesterol:phospholipid molar ratio and a high proportion of sphingomyelin. Together with the fact that prostasomes can rigidify the plasma membrane of blood PMN, these results led us to postulate that prostasomes inhibit the NADPH oxidase activity of PMN by lipid transfer from the prostasomes to the plasma membrane of the PMN.

Cholesterol↗
PubMed1998

Efficacy of radiosynovectomy of the knee in rheumatoid arthritis: evaluation with magnetic resonance imaging.

The intra-articular injection of a radiopharmaceutical agent (radiosynovectomy) produces a reduction of the synovial inflammatory process. The inflammed synovial membrane can be identified with magnetic resonance imaging after the intravenous administration of gadolinium (MRI-Gd). A 6-month prospective study was carried out in 10 patients with rheumatoid arthritis after radiosynovectomy of the knee. The efficacy was evaluated with clinical parameters and MRI-Gd. A progressive amelioration of synovial effusion, pain, articular range of mobility, total leucocytes count in synovial fluid and synovial membrane thickness through MRI-Gd was observed. The global efficacy was considered to be good in six patients, fair in three and bad in one. The study shows for the first time that MRI-Gd allows the evaluation of the response of the synovial membrane to radiosynovectomy.

Adult↗
PubMed1998

Grading of subcutaneous soft tissue tumors by means of their relationship with the superficial fascia on MR imaging.

OBJECTIVE: To assess the diagnostic value of the relationship between subcutaneous tumors and the superficial fascia in the characterization of soft-tissue masses. DESIGN: MR studies of 64 soft tissue masses located in the subcutaneous space were reviewed. We established five grades of relationship between tumors and superficial fascia and analyzed the probability of the lesions in each group being malignant. Group 1 tumors did not contact the fascia; group 2 lesions contacted it slightly, with acute angles between the tumor and the fascia; group 3 lesions had wider contact with larger acute or right angles; group 4 tumors had even wider contact with obtuse angles with the fascia; and group 5 was composed of lesions that crossed the superficial fascia. RESULTS: The probability of a subcutaneous lesion that crosses the superficial fascia being malignant was 6.88 times greater than for lesions that did not cross the fascia. For lesions forming obtuse angles with the fascia the probability of malignancy was 6.3 times greater than that of tumors that did not present this sign. All histologically verified fascial infiltrations occurred in malignant lesions of groups 4 and 5. CONCLUSIONS: Malignant tumors of the subcutaneous compartment have a higher tendency to develop a close relationship with the fascia than benign lesions. Obtuse angles between superficial fascia and a subcutaneous mass or a lesion crossing the fascia strongly suggest malignancy.

Carcinoma, Squamous Cell↗
PubMed1998

Antioxidant capacity of prostasomes in human semen.

Prostasomes are human-specific lipid vesicles originating from the prostate and present in seminal plasma. They are involved in a number of biological functions such as sperm motility and immunomodulation by seminal plasma. The aim of our study was to investigate whether prostasomes play a role in the antioxidant status of seminal plasma. In cell suspensions obtained after elimination of seminal plasma by centrifugation, reactive oxygen species (ROS) as measured by luminol-enhanced chemiluminescence were mainly produced by polymorphonuclear neutrophils (PMN). The addition of prostasomes to these cell suspensions lowered the overall ROS production in the basal state and after stimulation with phorbol ester. This action could not be explained by a ROS-scavenging capacity of the prostasomes, as demonstrated by their inability to scavenge ROS produced by 2,2'-azobis-2-amidinopropane dihydrochloride. Using electron spin resonance, we could assess the influence of prostasomes on the plasma membranes of blood PMN and show that it was characterized by an increase in the correlation-relaxation time of the probe 16-doxyl-stearic acid inserted in the membranes. Thus, prostasomes caused a rigidification of blood PMN membranes. These results strongly suggest that the effect of prostasomes in semen could result from their interaction with PMN.

Antioxidants↗
PubMed1996

Fat necrosis.

We report the MR appearance of a case of subcutaneous fat necrosis, which is a previously unreported etiology for knee mass. The role of MR imaging in differentiating fat necrosis from other causes of soft tissue masses is discussed. We conclude that MR characteristics of subcutaneous fat necrosis are typical and allow its differentiation from other types of soft tissue lesions.

Adolescent↗
PubMed1995

Therapeutic effect of early thymic irradiation in (NZB x NZW)F1 mice, associated with a selective decrease in the levels of IgG3 and gp70-anti-gp70 immune complexes.

The lupus-prone (NZB x NZW)F1 female mice (NZB/W) develop an autoimmune disease characterized by production of autoAb and fatal glomerulonephritis. Since it has been previously shown that total lymphoid irradiation has a beneficial effect in this model, we have analyzed whether early thymic irradiation (ETI) could improve the course of the lupus-like syndrome in these mice. NZB/W mice received thymic irradiation (4500 rads) beginning at 10 weeks of age, prior to the onset of autoimmune manifestations. Then, they were evaluated for survival, renal histology, and serological markers of autoimmunity, in comparison to nonirradiated NZB/W females. The treatment with ETI improved nephritis and survival in NZB/W mice: 50% mortality was observed at 12 months in irradiated mice and at 9 months in untreated mice. This improved survival could not be attributed to a reduction in the titers of anti-dsDNA Ab nor in the levels of total immune complexes which were essentially identical in both groups. By contrast, this improvement was related to a selective normalization in the serum levels of IgG3 and gp70-anti-gp70 immune complexes (gp70IC) in ETI NZB/W female mice as compared to that seen in nonirradiated NZB/W females. These data show the therapeutical effect of ETI and support the pathogenic role of IgG3 and gp70IC in the development of glomerulonephritis in NZB/W mice.

Animals↗
PubMed1991

Selection of thermotolerant yeasts for simultaneous saccharification and fermentation (SSF) of cellulose to ethanol.

A total of 27 yeast strains belonging to the groups Candida, Saccharomyces, and Kluyveromyces were screened for their ability to grow and ferment glucose at temperatures ranging 32-45 degrees C. K. marxianus and K. fragilis were found to be the best ethanol producing organisms at the higher temperature tested and, so, were selected for subsequent simultaneous saccharification and fermentation (SSF) studies. SSF experiments were performed at 42 and 45 degrees C, utilizing Solkafloc (10%) as cellulose substrate and a cellulase loading of 15 FPU/g substrate. Best results were achieved at 42 degrees C with K. marxianus L. G. and K. fragilis L. G., both of which produced close to 38 g/L ethanol and 0.5 ethanol yield, in 78 h.

Candida↗
PubMed1985

Transient idiopathic subpleural cysts in the newborn: an observation in two patients.

We present two cases of transient idiopathic cystic formations in the subpleural region in full-term newborns, that do not fit into any known cystic process to our knowledge. The features of the cystic formations, their subpleural location, their spontaneous regression, the histopathological study, as well as the absence of a clear etiology, have led us to propose the name of "Transient Idiopathic Subpleural Cysts in Full-term Newborns", for this process.

Cysts↗
PubMedDate not supplied

MRI diagnosis and follow-up of subcutaneous fat necrosis.

The purpose of this report is to present the MRI features of subcutaneous fat necrosis (SFN) and the natural history of this process. We have seen 12 patients with SFN, one case of which was confirmed histopathologically. In six patients, a follow-up MRI study was performed. MRI findings were very similar in all of the cases: small, linear, and spiculated lesions with one or two components: a globular area yielding high signal intensity on T1-weighted images, intermediate to high signal intensity on fast SE T2-weighted images and focal signal void on short-inversion -time inversion recovery (STIR) sequence, corresponding to an area of fat necrosis; and a laminar starred component, with low signal intensity on T1 and fast SE T2-weighted images and high signal intensity on the STIR sequence, corresponding to reactive fibrous tissue. The follow-up MRI study of six patients showed either disappearance (n = 2) or decrease in size (n = 3) of the globular component; in one patient, no change was observed. A less prominent decrease of the laminar component also was seen in five patients. One patient did not present any change in this laminar component. The most characteristic MRI findings of this lesion are the high signal intensity areas on T1-weighted images, their small size (< 3 cm), their linear spiculated shape with both laminar and globular components, and no contrast enhancement after injection of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) injection. We believe that the location, size, morphology, and MRI signal intensity of SFN may allow its differentiation from other types of soft tissue lesions.

Adolescent↗