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T Pascal

Publications and source records attributed to T Pascal.

At least 19 recordsLinked to original sources
PubMed2005

Analogues of virus resistance genes map to QTLs for resistance to sharka disease in Prunus davidiana.

Plum pox virus (PPV), the causative agent of sharka disease in Prunoideae, is one of the most serious problems affecting stone fruit production in Europe and America. Resistance to PPV was previously described in a Prunus davidiana clone, P1908, and introduced into peach (Prunus persica) genotypes. Genetic resistance to PPV displays a complex pattern of quantitative inheritance. An analysis of quantitative trait loci (QTLs) for resistance was performed on an F1 interspecific peach population obtained from a cross between the susceptible nectarine cultivar Summergrand and P. davidiana. The hybrids were graft-inoculated with PPV in duplicate following a classical procedure. The incidence of infection was evaluated four times, over two vegetative cycles, by symptom observation and enzyme-linked immunoadsorbent assays (ELISA). Restriction of systemic downward movement of the PPV virus was also evaluated by testing the susceptible rootstocks. Using both analysis of variance and non-parametric tests, six genomic regions involved in PPV resistance were detected. Depending on the scoring data considered, between 22 and 51% of the phenotypic variance could be explained by the quantitative model. One QTL, located in the distal region of linkage group 1, maps in a genomic region that is syntenic to the location of a resistance gene previously identified in the apricot cv. Goldrich. Some QTLs appeared to be temporally specific, reflecting the environmental dependence of PPV-resistance scoring. Candidate gene fragments were amplified by PCR, isolated and mapped on the peach interspecific linkage map. We report here the co-localization of three analogues of virus resistance genes with two distinct genomic regions linked to PPV resistance in P. davidiana.

Base Sequence↗
PubMed2005

[Stent-graft treatment of a ruptured aortic graft: a case report].

The authors report the clinical and imaging features of a patient with rupture of an aortoiliac graft successfully treated by endovascular approach. The endovascular treatment is easy to perform and effective. The main pitfall of this technique is the limited availability of stent-grafts.

Anastomosis, Surgical↗
PubMed2004

Preoperative diagnostic values of fine-needle cytology and MRI in parotid gland tumors.

The aim of this retrospective study was to assess and compare the diagnostic value of fine-needle cytology and MRI for the prediction of malignancy in parotid tumors. During an 11-year period, 148 patients underwent preoperative fine-needle aspiration cytology in our institution. Eighty-seven patients underwent a preoperative MRI study, and 54 had both MRI and cytology. The study compares results of cytology and MRI with histological reports. The sensitivity, specificity and accuracy for detecting malignant lesions were 87, 94 and 93% respectively for MRI, 81, 95 and 92% respectively for cytology and 100, 88 and 91% respectively for both studies combined. Fine-needle cytology provided better information than MRI concerning precise histological diagnoses. Conversely, the proportion of non-diagnostic smears reached 10%. Fine-needle cytology and MRI are simple, well-tolerated diagnostic means with an impact on the management of salivary gland tumors. The associated anatomic information obtained by MRI imaging makes it the test of first choice in an optimal medical environment.

Adolescent↗
PubMed2003

mtCLIC is up-regulated and maintains a mitochondrial membrane potential in mtDNA-depleted L929 cells.

To explain why mitochondrial DNA (mtDNA)-depleted or rho0 cells still keep a mitochondrial membrane potential (Delta(psi)m) in the absence of respiration, several hypotheses have been proposed. The principal and well accepted one involves a reverse of action for ANT combined to F1-ATPase activity. However, the existence of other putative electrogenic channels has been speculated. Here, using mRNA differential display reverse transcriptase-polymerase chain reaction on L929 mtDNA-depleted cells, we identified mtCLIC as a differentially expressed gene in cells deprived from mitochondrial ATP production. Mitochondrial chloride intracellular channel (mtCLIC), a member of a recently discovered and expanding family of chloride intracellular channels, is up-regulated in mtDNA-depleted and rho0 cells. We showed that its expression is dependent on CREB and p53 and is sensitive to calcium and tumor necrosis factor alpha. Interestingly, up- or down-regulation of mtCLIC protein expression changes Delta(psi)m whereas the chloride channel inhibitor NPPB reduces the Delta(psi)m in mtDNA-depleted L929 cells, measured with the fluorescent probe rhodamine 123. Finally, we demonstrated that purified mitochondria from mtDNA-depleted cells incorporate, in a NPPB-sensitive manner, more 36chloride than parental mitochondria. These findings suggest that mtCLIC could be involved in mitochondrial membrane potential generation in mtDNA-depleted cells, a feature required to prevent apoptosis and to drive continuous protein import into mitochondria.

Animals↗
PubMed2003

The potential of Prunus davidiana for introgression into peach [Prunus persica (L.) Batsch] assessed by comparative mapping.

The potential for introgression of Prunus davidiana, a wild species related to peach, was evaluated with respect to problems of non-Mendelian segregation or suppressed recombination which often hamper breeding processes based on interspecific crosses. Three connected (F1, F2 and BC2) populations, derived from a cross between P. davidiana clone P1908 and the peach cultivar Summergrand were used. The intraspecific map of P. davidiana already established using the F1 progeny was complemented, and two interspecific maps, for the F2 and BC2 progenies, were built with a set of markers selected from the Prunus reference map. With the molecular data collected for the F2 map construction, regions with distorted marker segregation were detected on the genome; one third of all loci deviated significantly from the expected Mendelian ratios. However, some of these distorted segregations were probably not due to the interspecific cross. On linkage group 6, a skewed area under gametic selection was most likely influenced by the self-incompatibility gene of P. davidiana. Using anchor loci, a good colinearity between the three maps built and the Prunus reference map was demonstrated. Comparative mapping also revealed that homologous recombination occurred normally between P. davidiana and the Prunus persica genome. This confirmed the closeness of the two species. Higher recombination rates were generally observed between P. davidiana and P. persica than between Prunus amygdalus and P. persica. The consequences for plant breeding strategy are discussed. The three maps of the F1, F2 and BC2 progenies provide useful tools for QTL detection and marker-assisted selection, as well as for assessing the efficiency of the peach breeding scheme applied to introgress P. davidiana genes into peach cultivated varieties.

Breeding↗
PubMed2003

[Sphenoid sinusitis].

Sphenoid sinusitis is uncommon, with an incidence of about 2.7%. Failure to diagnose and treat sphenoid sinus disease has been shown to lead to serious neurologic sequellae. Plain radiographs play a limited role in the management of sinusitis. CT scan can provide a positive diagnosis by the visualization of mucosal thickening, air-fluid level and complete opacification of the sinusal cavities. In addition, CT can provide more information about the anatomy and abnormalities of the sphenoid sinus. MRI is used in cases of suspected tumors or neurologic involvement. The most common presenting symptom is headache that arise characteristically, but rarely, from the vertex. Sphenoiditis has a high risk of severe neurologic involvement, cavernous sinus thrombosis being one of the most serious complications.

Cavernous Sinus Thrombosis↗
PubMed2001

Growth kinetics rather than stress accelerate telomere shortening in cultures of human diploid fibroblasts in oxidative stress-induced premature senescence.

WI-38 human diploid fibroblasts underwent accelerated telomere shortening (490 bp/stress) and growth arrest after exposure to four subcytotoxic 100 microM tert-butylhydroperoxide (t-BHP) stresses, with a stress at every two population doublings (PD). After subcytotoxic 160 microM H2O2 stress or five repeated 30 microM t-BHP stresses along the same PD, respectively a 322 +/- 55 and 380 +/- 129 bp telomere shortening was observed only during the first PD after stress. The percentage of cells resuming proliferation after stress suggests this telomere shortening is due to the number of cell divisions accomplished to reach confluence during the first PD after stress.

Cell Division↗
PubMed2001

[Pre- and postnatal diagnosis of omphalo-xiphopagus conjoined twins].

We report a case with successful surgical separation of female omphalo-xiphopagus conjoined twins. Ultrasonographic examination at 20 weeks of gestation showed twins joined at the abdomen from the xiphoid process to the umbilicus. Conjoined structures included liver. Karyotype was normal. The parents refused interruption of the pregnancy. Plain films, US and MRI confirmed findings at prenatal ultrasound examination. There was no cross circulation into the livers and the gastrointestinal tract was not conjoined. In our observation, postnatal MRI did not offer additional information.

Female↗
PubMed2000

Stress-induced premature senescence as alternative toxicological method for testing the long-term effects of molecules under development in the industry.

No alternative in vitro method exists for detecting the potential long-term genotoxic effects of molecules at subcytotoxic concentrations, in terms of days and weeks after exposure(s) to the molecule tested. A theoretical model of cellular senescence led to the concept that subcytotoxic stresses under any molecules at subcytotoxic doses, such as molecules under development in the pharmaceutical, cosmetics and food industry, might lead human fibroblasts into a state closely related to in vitro senescence. This concept was then experimentally confirmed in vitro: many biomarkers of replicative senescence of human fibroblasts were found 72 h after their exposure to various kinds of stressors used at non-cytotoxic concentrations. This phenomenon has been termed stress-induced premature senescence (SIPS). Moreover, proteomics studies have revealed that, besides their effects on the appearance of the biomarkers of senescence, sublethal stresses under a variety of stressors also lead to long-term specific changes in the expression level of proteins which are stress-specific. These changes have been coined the molecular scars of stress. The proteins corresponding to these molecular scars may be identified using the latest developments in mass spectrometry. This model of stress-induced premature senescence may be applied to the toxicological sciences when testing for the potential irreversible long-term effects of molecules on the cell fate.

Aging, Premature↗
PubMed2000

Identification of hypoxia-responsive messengers expressed in human microvascular endothelial cells using differential display RT-PCR.

In order to identify new genes overexpressed in endothelial cells exposed to hypoxia, differential display RT-PCR was performed on total RNA extracted from human microvascular endothelial cells incubated under hypoxia or under normoxic conditions. Northern blot and reverse Northern blot analyses were used to confirm the results. Sequences corresponding to tissue inhibitor of metalloproteinase-1, prostate tumor inducing factor-1, enolase-alpha and prothymosin-alpha were evidenced as overexpressed in hypoxia. These results were confirmed by Western blot and immunofluorescence experiments. Moreover, several elements homologous to partial sequences of cDNA (expressed sequence tag) were also identified, as well as unknown cDNA sequences. The present study suggests that hypoxia can change the expression of numerous genes in endothelial cells, and that mRNA differential display is useful for cloning known and unknown hypoxia-responsive genes.

Cell Hypoxia↗
PubMed2000

[Primitive neuroectodermal tumor of the kidney manifested as a spontaneous hematoma].

Ultrasound and CT in a young man, admitted for violent left flank pain, revelead a large heterogeneous left renal mass, with hypodense collection along the psoas. The diagnosis was spontaneous renal hematoma. A check CT 3 weeks later found a large tumor of the inferior pole. After radical nephrectomy, histopathology diagnosed a primitive neuroectodermal tumor. The patient died one year later despite neoadjuvant chemotherapy. This article reports the clinical, radiological and histopathological aspect of a primitive neuroectodermal tumor of the kidney, compared with the other cases in literature.

Adult↗
PubMed1999

[Prostatic ultrasonography in routine radiological practice: a survey of 122 radiologists].

OBJECTIVE: To evaluate the indications and practical modalities of prostatic ultrasonography in routine radiological practice. METHODS: An anonymous questionnaire composed of 18 multiple choice questions was sent to 122 radiologists. RESULTS: Among the 76 responses, 90% were men, 90% were in private practice and 94% regularly performed prostatic ultrasonography without clinical information (81%). The prostatic examination was performed by transrectal ultrasonography (60%) combined with vesical and renal ultrasonography. The indications were: urinary functional disorders (56%) and abnormal PSA (40%). Prostatic ultrasonography was considered to be useful to calculate prostatic volumes by 59% of radiologists and in the staging of prostatic cancer (81%). 80% of radiologists did not start by performing digital rectal examination. 59% of patients were informed. CONCLUSION: The observed indications did not correspond to urological consensus recommendations, but ultrasonography was performed according to classical recommendations. This study could justify a more precise definition of the role of ultrasonography in prostatic disease.

Adult↗
PubMed1999

[Renal malakoplakia: prognostic aspects].

We report the changes in imaging findings over a 5 year period of a patient with unilateral malakoplakia involving renal parenchyma and pelvis. The imaging findings of malakoplakia will be reviewed.

Adult↗
PubMed1984

Sulfhydryl oxidase in human milk: stability of milk enzymes in the gastrointestinal tract.

Sulfhydryl oxidase (SOX) is present in human milk and in milk from all species that have been studied. The pH optimum of human milk SOX is in the neutral range between 7.0 and 7.5. Human milk SOX is stable in an acid environment: 50% of its activity remains after 1 h at pH 2.5. Acid stability is also characteristic of gamma-glutamyltranspeptidase, another membrane-bound enzyme in skim milk. SOX is resistant to pepsin (4000 U/ml), trypsin (50 micrograms/ml), chymotrypsin (200 micrograms/ml), and to trypsin plus chymotrypsin (25 micrograms each/ml). Milk SOX activity has been detected in the stomach and proximal small intestine contents of suckling rats. Human and bovine SOX are relatively heat stable: 75% of the latter remains after treatment at 62.5 degrees C for 30 min and 65% of the former remains after treatment at 60 degrees C for 10 min. Neither remains after 62.5 degrees C for 30 min.

Animals↗