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F Vidal

Publications and source records attributed to F Vidal.

At least 109 records · Page 6Linked to original sources
PubMed1998

FISH on sperm heads allows the analysis of chromosome segregation and interchromosomal effects in carriers of structural rearrangements: results in a translocation carrier, t(5;8)(q33;q13).

Using three-color fluorescence in situ hybridization (FISH) with specific DNA probes, we have determined the chromosome segregation pattern of the translocated chromosomes in a human male carrier of a reciprocal translocation, t(5;8)(q33;q13). At the same time, we have assessed the possible interchromosomal effect on pair 21 using dual-color FISH. The segregation results showed that a 45.12% of the spermatozoa analyzed resulted from alternate segregation, 38.31% resulted from adjacent I, 6.97% from adjacent II, and 6.56% from 3:1 segregation. Finally, 1.23% could be either diploid sperm or 4:0 segregation. In both types of adjacent segregations, an excess of products containing short translocated segments (adjacent I) and interstitial regions (adjacent II) were found. Products resulting from the presence of an interstitial chiasma in pair 5 (1.26%), were found much more frequently (P < 0.0001) than those resulting from an interstitial chiasma in pair 8 (0.13%) (evaluated after adjacent II segregation). In 3:1 segregation, the products containing one chromosome were observed more frequently than those containing three chromosomes (P < 0.0001). No evidence of an interchromosomal effect on chromosome 21 was detected, the percentage of disomy 21 being similar to that in the controls (0.23% vs. 0.37%). However, the percentage of diploid sperm (1.18%) was significantly higher (P < 0. 0001) than that in the controls (0.27%). FISH therefore appears to be a useful technique for assessing the percentage of abnormal sperm in translocation carriers. Their application in assisted reproduction centers could offer patients more accurate genetic counseling.

Adult↗
PubMed1998

An unusual presentation of secondary pleural hydatidosis.

Although pleural involvement is relatively common in cystic hydatid disease, one of the rarest and least known complications is secondary pleural hydatidosis. We report the case of a patient who presented with polycystic secondary pleural hydatidosis 4 yrs after treatment for a pyopneumothorax caused by rupture of a pulmonary cyst near the pleural space. Due to the coexistence of severe chronic obstructive pulmonary disease, surgery was ruled out. The patient was treated with albendazole, with a favourable outcome.

Aged↗
PubMed1998

[Diltiazem compared with placebo in the prevention of myocardial ischemia during non-cardiac surgery].

OBJECTIVE: The aim of this study was to assess the efficacy and safety of intravenous diltiazem to prevent myocardial ischemia during surgery on patients with ischemic heart disease undergoing non cardiac surgery under general anesthesia. PATIENTS AND METHOD: Sixty patients scheduled for elective non cardiac surgery under general anesthesia were randomly assigned to two groups to receive diltiazem or placebo under double blind conditions. After an intravenous dose of 0.15 mg/kg of diltiazem or an equivalent amount of placebo, an infusion of 3 micrograms/kg/min of diltiazem or placebo was begun and continued until three hours after surgery. Thirty minutes after starting the infusion, anesthesia was induced by 0.1 mg/kg diazepam, 3 micrograms/kg of fentanyl and 0.3 mg/kg of etomidate. Intubation followed administration of 0.6 mg/kg of atracurium. Anesthesia was maintained with N2O/O2 and halothane and was the same for both groups. DII and V5 leads were monitored on a Cardiowiss CM-8 ECG machine that allowed us to set the alarm when ST segment variations reached 1 mm above or below baseline. We analyzed the number, intensity and duration of ischemic episodes recorded, as well as hemodynamic variables and side effects. RESULTS: Data for 46 patients were valid. At least one ischemic episode was experienced by 15% of patients in the placebo group and 1 in the diltiazem group (p < 0.05). The episodes were related to increased systolic arterial pressure (p = 0.04). ST segment decreases were 1.1 to 3.6 mm (1.75 +/- 0.7) (mean +/- SD) and lasted between 1 and 45 minutes (11.62 +/- 13.26) (mean +/- SD). No significant side effects were observed. CONCLUSIONS: Intravenous diltiazem administered to patients with ischemic heart disease under general anesthesia for non cardiac surgery was effective in our study for preventing intraoperative ischemic episodes.

Aged↗
PubMed1997

The basic pattern of activation in motor and sensory temporal tasks: positron emission tomography data.

Positron emission tomography (PET) data were obtained from subjects performing a synchronization task (target duration 2700 ms). A conjunction analysis was run to identify areas prominently activated both in this task and in a temporal generalization task (target duration 700 ms) used previously. The common pattern of activation included the right prefrontal, inferior parietal and anterior cingulate cortex, the left putamen and the left cerebellar hemisphere. These areas are assumed to play a major role in time processing, in relation to attention and memory mechanisms.

Adult↗
PubMed1997

[Yield of blood cultures in relation to the cultured blood volume in Bactec 6A bottles].

BACKGROUND: Concentration of microorganisms in blood is low in bacteremia from extravascular sources. The best yield from blood cultures is achieved by culturing a minimum of 10-20 ml, although in some processing blood culture systems such as Bactec NR-860, smaller volume is used. The objectives of the present study were to establish the frequency in which inadequate small blood volumes are employed for culturing and to analyze the relation between the cultured blood volume in Bactec 6A bottles and the yield achieved. MATERIAL AND METHODS: We weighed 2000 Bactec 6A bottles pertaining to consecutive blood cultures obtained from untreated patients with clinical suspicion of Infection. The cultured blood volume was estimated subtracting the mean empty bottle weight. RESULTS: Microorganisms were recovered from 251 bottles (12.5%). One hundred and thirty one (6.8%) isolates were considered as clinically significant and 115 (5.7%) as contaminant. The inoculated blood volume in both significant (5.532 +/- 1.587 ml) and non-significant (5.471 +/- 1.563 ml) recoveries was superior than that of bottles without microbiologic growth (5.209 +/- 1.575 ml, p = 0.016 and p = 0.06, respectively). A linear positive trend was found between the cultivated blood volume and the rate of recoveries (p = 0.008). Within the range of 1 up to 10 ml, the rate of recoveries increased 2.28% for each additional ml of cultivated blood (r = 0.953, p < 0.0001). Out of the 2,000 weighed bottles 127 (6.3%) contained less than 3 ml of blood and 576 (29%) between 3 and 5 ml. CONCLUSIONS: We have proved that the rate of recoveries from Bactec 6A bottles increased with the volume of cultured blood. In untreated patients, this increase is maintained up to volumes of 7 to 10 ml.

Adult↗
PubMed1997

Alcohol dehydrogenase of human and rat blood vessels. Role in ethanol metabolism.

Alcohol dehydrogenase (ADH) activity has been detected in all arteries and veins examined from humans and rat. In distinct human autopsy vessels, activity values range from 0.9 +/- 0.2 to 9.9 +/- 7.7 mU/mg. Distribution of the activity in human aorta was: intima (23.5%), media (74%) and adventia (2.5%). In most of the samples the beta1 beta1 isozyme of class I ADH was the only form responsible for the ADH activity. Class IV ADH (sigma sigma-ADH) was present in three of the 28 individuals examined. The rat blood vessels showed class IV, but not class I, ADH localized in endothelium and media. The physiological role of vascular ADH is probably related to retinoid metabolism and elimination of lipid peroxidation aldehydes. A contribution to human ethanol metabolism is supported by the significant amount of low-Km activity and the extension of the vascular system.

Adult↗
PubMed1997

Cryopreservation of caprine beta-lactoglobulin transgenic mouse embryos.

As an economical and safer alternative to the maintenance of transgenic animals as live stocks, transgenic embryo cryobanks can be generated and maintained indefinitely. Two-cell embryos obtained from four lines of caprine beta-lactoglobulin transgenic mice homozygous for the transgene were cryopreserved, and their response to cryopreservation-related stress was investigated. Significant differences between transgenic lines were found in the viability of frozen/thawed transgenic embryos and also in two-cell embryo production after superovulatory treatment of transgenic females. The results of this study suggest that cryopreservation protocols should be assessed on each transgenic line before the generation of transgenic embryo banks.

Animals↗
PubMed1997

Increased incidence of disomic sperm nuclei in a 47,XYY male assessed by fluorescent in situ hybridization (FISH).

Using triple-colour fluorescent in situ hybridization in decondensed sperm heads, we assessed the sex-chromosome distribution in spermatozoa from a 47,XYY male compared with controls. The incidence of spermatozoa with 24,XY (0.30%) and 24,YY (1.01%) disomy was significantly higher than in our control series. Diploid meiocytes present in the ejaculate were mainly 47,XYY (60.6-86.7%), and haploid meiocytes were mainly 24,XY (78.1%).These results suggest that, although the extra Y chromosome is thought to be eliminated during spermatogenesis, XYY germ cells can complete meiosis and produce disomic spermatozoa.

Adult↗
PubMed1997

Chromosome segregation in a man heterozygous for a pericentric inversion, inv(9)(p11q13), analyzed by using sperm karyotyping and two-color fluorescence in situ hybridization on sperm nuclei.

Analysis of sperm karyotypes and two-color fluorescent in situ hybridization (FISH) on sperm nuclei were carried out in a man heterozygous for the pericentric inversion inv(9)(p11q13). Sperm chromosome complements were obtained after in vitro fusion of zona-free hamster oocytes and donor sperm. A total of 314 sperm complements was analyzed: 153 (48.7%) carried the inverted chromosome 9 and 161 (51.3%) carried the normal one. None of the sperm complements contained a recombinant chromosome 9, suggesting that no chiasmata were formed in the heterochromatic region. The frequency of structural chromosome aberrations unrelated to the inversion (8.3%) and the frequency of conservative aneuploidy (3.2%) were within the limits observed in our control donors. The proportions of X-bearing (47.3%) and Y-bearing sperm (52.7%) were not significantly different from the expected 1:1 ratio. The percentage of disomy for chromosome 21 was analyzed by two-color FISH in 10336 sperm nuclei. The disomy rate for chromosome 21 (0.30%) was not significantly different from that found in our controls. These results suggest that the risk for this man of producing chromosomally abnormal offspring or spontaneous abortions was not increased, and do not support the existence of an interchromosomal effect for chromosome 21.

Adult↗
PubMed1997

Mevalonate deprivation impairs IGF-I/insulin signaling in human vascular smooth muscle cells.

3-Hydroxy-3-methylglutaryl Coenzyme A (HMG-CoA) reductase inhibitors (statins) are therapeutically used to lower plasma cholesterol levels. In addition, these drugs can block vascular smooth muscle cell (VSMC) proliferation. The present study addressed the question whether the inhibitory effect of lovastatin on premitotic DNA synthesis correlates with a downregulation of c-fos mRNA levels, a marker of signaling efficiency, in human SMC. Here we show that in human SMC exposed to individual growth factors (platelet-derived growth factor, epidermal growth factor, alpha-thrombin, insulin, insulin-like growth factor I (IGF-I)) and human serum, the maximal [3H]thymidine incorporation and c-fos mRNA expression are closely correlated. Only alpha-thrombin elicited overexpression of c-fos as compared with its effect on [3H]thymidine incorporation. Lovastatin efficiently inhibited [3H]thymidine uptake promoted by all mitogens tested (76-87%); however, it significantly inhibited upregulation of c-fos mRNA levels induced only by insulin (33-67%, P < 0.05) and IGF-I (31 57%, P < 0.05). This inhibition was overcome by mevalonate and geranylgeraniol, and partially by farnesol. c-fos mRNA expression induced by 4-beta-phorbol-12-myristate-13-acetate, an activator of protein kinase C, was insensitive to lovastatin treatment. Thus, in human vascular SMC, lovastatin impairs premitotic DNA synthesis induced by growth factors, but only c-fos expression promoted by insulin and IGF-I. These data indicate that statin-sensitive and -insensitive pathways seem to be involved in the regulation of c-fos in the response of human SMC to proliferative stimuli, and suggest a prominent role of isoprenylated proteins in the activation of VSMC through the IGF-I/insulin dependent pathways.

Cells, Cultured↗
PubMed1997

Expression of caprine beta-lactoglobulin in the milk of transgenic mice.

A 14.5 kb-long transgene containing the complete caprine beta-lactoglobulin gene transcription unit as well as 6.1 kb and 3.7 kb of the 5'- and 3'-flanking regions, respectively, was microinjected into pronuclear stage mouse embryos. Four lines of transgenic mice were obtained, three of them expressing the transgene in their mammary glands during lactation. Western blot analysis of caprine beta-lactoglobulin in the milk of hemizygous transgenic animals demonstrated the presence of the exogenous protein at concentrations up to 0.5 mg ml-1 of mouse milk.

Animals↗
PubMed1997

Origin of tripronucleate zygotes after intracytoplasmic sperm injection.

Zygotes morphologically classified as tripronuclear (3PN) after intracytoplasmic sperm injection (ICSI), which are thought to be digynic in their origin, were studied by fluorescent in-situ hybridization (FISH). FISH results allowed us to assess the suspected ploidy after morphological evaluation of the zygote and to determine the origin of the third pronuclei. Our results show that, firstly, 36% of those zygotes classified as 3PN following their morphological evaluation were, in fact, diploid, and secondly, the main cause for triploidy after ICSI is the non-extrusion of the second polar body.

Cell Nucleus↗
PubMed1997

An epidural abscess due to resistant Staphylococcus aureus following epidural catheterisation.

We report a case of abscess formation after epidural analgesia, a rare complication that developed in our patient 13 days after placement of a thoracic epidural catheter for patient controlled analgesia. Culture of the pus grew methicillin-resistant Staphylococcus aureus. Although early diagnosis and rapid management have been reported to yield a satisfactory outcome, the case we describe ended in severe sequelae.

Abscess↗
PubMed1997

Fatal Listeria meningitis, endocarditis and pericarditis in a patient with haemochromatosis.

A 65-year-old man with primary haemochromatosis was admitted because of fever and confusion. He was found to have bacteraemia and meningitis due to Listeria monocytogenes. Treatment with ampicillin plus tobramycin was instituted, and despite an initial improvement, the patient experienced an unfavourable course and died. At postmortem examination, tricuspid valve endocarditis and purulent pericarditis with tamponade were detected. Listeria monocytogenes grew in the culture of the pericardial fluid. Documentation of Listeria monocytogenes pericarditis is extremely rare, and data on the patient described and on seven published cases are reported.

Aged↗