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C Soler

Publications and source records attributed to C Soler.

At least 109 records · Page 6Linked to original sources
PubMed1993

Detection of mucosal human papillomavirus types 6/11 in cutaneous lesions from transplant recipients.

Transplant recipient develop multiple cutaneous lesions. We have identified human papillomavirus (HPV) DNA in these lesions using three different techniques, namely polymerase chain reaction (PCR), in situ hybridization, and Southern blotting. By PCR, HPV DNA was detected in 43 of 62 samples: warts, actinic keratoses, Bowen's disease, and squamous cell carcinomas. Surprisingly, HPV 6/11, usually associated with mucosa, were frequently found in benign, premalignant, and malignant cutaneous lesions (30/43 cases). Some of these biopsies were simultaneously tested by in situ hybridization and/or Southern blotting. By in situ hybridization, HPV 6/11 were identified in two warts and one squamous cell carcinoma among 29 tissue specimens tested. Of the three samples examined by Southern blotting, HPV 6/11 were detected in one squamous cell carcinoma. In patients from a control population cutaneous biopsies did not exhibit HPV types 6/11 except in Bowen's disease; HPV types 1 or 2 were mainly found in benign warts. These findings suggest that in transplant recipients, HPV can lose their specificity towards mucosa or cutaneous epithelium. The significance of the presence of HPV 6/11 in skin lesions remains unknown.

Base Sequence↗
PubMed1993

Ornithine decarboxylase activity and urea in liver of late-pregnant rats. Effect of streptozotocin-induced diabetes.

It has been suggested that the induction of ornithine decarboxylase (ODC) activity during pregnancy might contribute to the low ureagenic flux that enables the pregnant mother to spare nitrogen and support growth. Thus, we have studied the ODC activity, and urea and polyamine levels in livers of virgin and 21-day pregnant rats, either in a basal state or after the induction of ureagenesis by inducing diabetes in rats by streptozotocin injection. Diabetes led to a marked increase in circulating and liver urea levels in virgin rats. This response was significantly reduced in late-pregnant animals. Diabetes did not modify ODC activity in pregnant rats, which showed much lower activities than their virgin controls. Diabetes caused a depletion of the liver spermine content in pregnant rats. Spermidine levels were higher in both groups of pregnant animals than in their respective controls. Our results suggest first that the mechanisms contributing to spare nitrogen in the pregnant mother are likely to be present in diabetic pregnant animals and, second, that ODC does not mediate the metabolic adaptations leading to a low ureagenic flux and a higher nitrogen retention at the last stage of pregnancy.

Animals↗
PubMed1993

[Anti-cytoplasm antibodies to polynuclear neutrophils: specificity in renal vasculitis].

We present a retrospective study of all patients with a positive anti-neutrophil cytoplasm autoantibodies (ANCA) result from July 1987 to December 1990. The aims of the study were to assess specificity of ANCA in renal vasculitis and to correlate ANCA immunofluorescence subtypes with clinical aspect, diagnosis, severity and outcome. Anti-myeloperoxidase antibody (A-MPO) was sought in 31 cases. Specificity was 86% and false-positive results were 11%. ANCA subtypes varied with the clinical picture. C-ANCA were more often present when renal vasculitis was associated with pulmonary and ear, nose and throat involvement; P-ANCA were more often present when there was no respiratory tract involvement. Thus C-ANCA were preferentially associated with Wegener's granulomatosis and P-ANCA with microscopic polyarteritis and pauci-immune necrotizing and crescentic glomerulonephritis. No correlation was found between ANCA subtypes and severity or outcome. A-MPO were positive in 14 cases (especially in micropolyarteritis and necrotizing glomerulonephritis).

Autoantibodies↗
PubMed1992

Amino acid deprivation leads to the emergence of System A activity and the synthesis of a specific membrane glycoprotein in the bovine renal epithelial cell line NBL-1.

1. Amino acid deprivation of confluent monolayers of the bovine renal epithelial cell line NBL-1 causes a stimulation of Na(+)-dependent alanine transport. 2. This stimulation is mediated by a protein-synthesis-dependent induction of 2-(methylamino)isobutyric acid (methyl-AIB)-sensitive alanine transport activity (System A), which was not previously present in these cells. 3. Induction was prevented by the addition of methyl-AIB, alanine or glutamine. 4. Tunicamycin prevented the induction of alanine transport activity. 5. Induction of System A activity was accompanied by incorporation of [3H]mannose into a single membrane protein band of molecular mass 113-140 kDa. 6. These results are consistent with the possibility that induced System A activity in confluent NBL-1 cells is mediated by the synthesis of a 113-140 kDa membrane glycoprotein.

Alanine↗
PubMed1992

Lipoprotein lipase and hepatic lipase activities are differentially regulated in isolated hepatocytes from neonatal rats.

Lipoprotein lipase and hepatic lipase are members of the lipase gene family sharing a high degree of homology in their amino acid sequences and genomic organization. We have recently shown that isolated hepatocytes from neonatal rats express both enzyme activities. We show here that both enzymes are, however, differentially regulated. Our main findings are: (i) fasting induced an increase of the lipoprotein lipase activity but a decrease of the hepatic lipase activity in whole liver, being in both cases the vascular (heparin-releasable) compartment responsible for these variations. (ii) In isolated hepatocytes, secretion of lipoprotein lipase activity was increased by adrenaline, dexamethasone and glucagon but was not affected by epidermal growth factor, insulin or triiodothyronine. On the contrary, secretion of hepatic lipase activity was decreased by adrenaline but was not affected by other hormones. (iii) The effect of adrenaline on lipoprotein lipase activity appeared to involve beta-adrenergic receptors, but stimulation of both beta- and alpha 1-receptors seemed to be required for the effect of this hormone on hepatic lipase activity. And (iv), increased secretion of lipoprotein lipase activity was only observed after 3 h of incubation with adrenaline and was blocked by cycloheximide. On the contrary, decreased secretion of hepatic lipase activity was already significant after 90 min of incubation and was not blocked by cycloheximide. We suggest that not only synthesis of both enzymes, but also the posttranslational processing, are under separate control in the neonatal rat liver.

Animals↗
PubMed1992

Detection of multiple types of human papillomavirus in a giant condyloma from a grafted patient. Analysis by immunohistochemistry, in situ hybridisation, Southern blot and polymerase chain reaction.

Immunosuppressed patients such as transplant recipients are known to develop multiple lesions suggestive of human papillomavirus (HPV) infection. A giant anal condyloma was obtained from a transplant patient; several fragments taken from different areas were examined for the presence of HPV DNA using in situ hybridisation, polymerase chain reaction (PCR) and Southern blot. Typical koilocytes were seen in routinely stained tissue sections, suggesting an HPV infection; furthermore, group specific HPV antigen was detected in one of four frozen fragments. Different results were obtained by in situ hybridisation according to the fragment tested. HPV types 6/11 were detected in each of the five fragments, frozen or fixed in Bouin's or formalin solutions. However, the number of HPV DNA positive cells and the intensity of the reaction greatly varied with the specimen. HPV 16 and 18 probes also reacted positively with the sample fixed in formalin; a stronger signal was observed with HPV 18 in one large focus than with HPV 16. HPV type 5 was detected in a few isolated cells of two frozen fragments. With the Southern blot technique, the profile of an HPV 6/11 was seen only in one of two frozen fragments; in this case, the bands were intense. A slight positive reaction was also obtained in one frozen fragment with HPV 16 probe. Four frozen fragments were analyzed with PCR: HPV 6/11 was detected in each fragment; HPV 18 was detected in the four samples but with different intensities; HPV types 5 and 16 did not show any positive signal. In conclusion, the lesion is an example of infection with several HPV types, demonstrated by three different techniques. This suggests the need for careful dermatological or colposcopic follow-up of transplant recipients, in order to prevent possible malignant transformation of anogenital lesions.

Adolescent↗
PubMed1992

c-myc and c-Ha-ras cellular oncogenes and human papillomaviruses in benign and malignant cutaneous lesions.

To analyze the role of human papillomavirus (HPV) infection and c-myc and c-Ha-ras oncogene activation in cutaneous and mucosal lesions, serial frozen sections of 47 lesions from grafted recipients and 10 biopsies from non-immunosuppressed patients were examined. HeLa, CaSki, MCF7, Colo 320 and 3T3 cells, which contain various copy numbers of HPV DNA and/or c-myc gene, were used as controls. HPV, myc and ras oncogene DNAs were not detected in normal epithelia by in situ hybridization with biotinylated DNA probes. The amplification of ras oncogene was detected in 20/57 lesions. The amplification of myc oncogene was found in 14/57 lesions, 13 of which showed both myc and ras gene amplification. c-myc and/or c-Ha-ras DNA was more frequently amplified in cutaneous squamous cell carcinomas (8/14 cases) and anogenital papillomas (4/6 cases), than in common and plantar warts (3/14 cases) or actinic keratoses (2/10 cases). HPV DNA was detected in 26/57 biopsies. Oncogene amplification was codetected with HPV DNA in 10/26 lesions, each of them containing at least one potentially oncogenic HPV type (5,16 and/or 18). The amplification was also found in 11/31 cases in the absence of HPV DNA. No significant difference was observed in the detection of HPV or oncogene DNA between the lesions of transplant recipients and those of the non-immunosuppressed population. Viral antigen was detected in 17/55 lesions by indirect immunofluorescence; 5 of the positive biopsies showed ras oncogene amplification. Myc and ras p21 oncoproteins were respectively localized in the nuclei and on the membrane of epithelial cells by indirect immunofluorescence. A good correlation was observed between the amplification of oncogenes and the expression of oncoproteins. Our results favor the hypothesis of a cooperation between HPV infection and myc and ras oncogene activation in skin carcinogenesis.

Blotting, Southern↗
PubMed1992

Influence of fixation on human papillomavirus DNA detection in frozen and embedded paraffin lesions by in situ hybridization with biotinylated probes.

Series of frozen or paraffin-embedded tissues from various body sites, taken from non-immunosuppressed or immunosuppressed patients with persistent papilloma lesions were examined for the presence of group specific antigen from human papillomavirus (HPV) by indirect immunofluorescence or HPV DNA by in situ hybridization with biotinylated probes. We have shown that it is possible to detect HPV DNA after fixation of tissues in neutral formalin, Bouin's or Baker's solution. However, the sensitivity was reduced as compared to frozen tissues. The HPV DNA was detected in nuclei of heavily infected epithelial cells such as plantar or hand warts or in dispersed cells containing high copy numbers of HPV DNA from lesions such as squamous cell carcinomas or keratoacanthomas. In premalignant or malignant lesions of both immunosuppressed or non-immunosuppressed patients, HPV DNA was rarely detected after fixation. HPV types commonly described for skin and genital samples were identified in non-immunosuppressed patients, whereas in transplant recipients oncogenic HPV type 16 was identified in benign warts as well as in premalignant or malignant lesions. Positive reactions with several HPV types were more frequent in lesions from grafted patients than from the normal population. Virus antigen was detectable more frequently in frozen sections than in fixed tissues. Our findings indicate that in situ hybridization is an appropriate and rapid technique to study the presence of HPV infection. However, numerous controls are needed to avoid misinterpretations.

Antigens, Viral↗
PubMed1992

Evaluation of human papillomavirus type 5 on frozen sections of multiple lesions from transplant recipients with in situ hybridization and non-isotopic probes.

Transplant recipients are at high risk to develop multiple cutaneous lesions after grafting. The frequency of the potentially oncogenic human papillomavirus (HPV) type 5 DNA was evaluated in cutaneous lesions taken from sun-exposed areas in transplant recipients (92 lesions and 5 samples from normal skin) and compared with a nontransplanted population (22 lesions and 7 samples from normal skin) using in situ hybridization and biotinylated probes to HPV types 1, 2, 5, 16 and 18. HPV type 5 DNA was identified in 8/92 cutaneous lesions of transplanted recipients: 3 warts, 1 case of seborrheic keratosis, 2 actinic keratoses and 2 keratoacanthomas. HPV type 5 DNA was not detected in 27 malignant tumors (8 basal cell carcinomas and 19 squamous cell carcinomas) from transplant recipients. HPV DNA type 5 was detected in only 1 case of squamous cell carcinoma from the general population. The presence of HPV DNA 5 was confirmed with Southern blotting in 2 out of 6 cases from transplant recipients. The reaction was negative with the squamous cell carcinoma from nontransplant recipients. These data indicate that the presence of HPV DNA type 5 is not very frequent; it can be detected with in situ hybridization and nonisotopic probe, which is easier to handle than Southern blot.

Biopsy↗
PubMed1992

[Micropolyarteritis].

Micropolyarteritis are defined as necrotizing inflammatory lesion of the wall of small vessels affecting different organs. A necrotizing crescentic glomerulonephritis without immuno-deposits is observed in the kidney, frequently involved in this microscopic form of systemic vasculitis. Micropolyarteritis are regrouped with Wegener's syndrome and isolated pauci-immune necrotizing crescentic glomerulonephritis as "ANCA-related vasculitis", whose diagnosis is assessed throw renal biopsy and prognosis dependent on immuno-suppressive treatment. Sixty-one patients treated in our nephrology department for a RPGN during these ten recent years have been retrospectively studied. Among them, twenty-five patients presented clinical and morphologic aspects compatible with the diagnosis of micropolyarteritis. We present their clinical aspects and evolution under treatment.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1992

[Contribution of chemiluminescence for determination of low value TSH in patients with dysthyroidism during negative TRH test].

TSH values performed by immunoradiometric method were compared with chemiluminescent method in 28 hyperthyroid patients with negative TRH-test. This last method gives a better sensitivity (0.020 mUI/L vs. 0.050 mUI/L) and reproducibility (5% V.C. vs. 40%). The measure of undetectable TSH by immunoradiometric assay becomes possible with chemiluminescence. Due to this increase of sensitivity, the TRH-test needs to be reconsidered and allows to discriminate various degrees of TSH suppression.

Adult↗
PubMed1992

[Human papillomaviruses and cellular oncogenes (c-myc, c-Ha-ras) in cutaneous and mucosal lesions in transplantation recipients].

Transplant recipients develop numerous benign and malignant cutaneous and mucosal lesions in which histological signs of human papillomavirus (HPV) infection are observed. To investigate the role of HPV and c-myc and c-Ha-ras cellular oncogenes' activation in transplanted patients lesions, we used in situ hybridization with biotinylated probes and Southern blot to detect HPV and oncogenes DNA. We analyzed 36 lesions from grafted patients: 11 common warts, 10 actinic keratoses, 13 squamous cell carcinomas and 2 anogenital papillomas. With in situ hybridization, HPV DNA was detected in 14/36 lesions, 10 of which contained several HPV types. Benign and potentially oncogenic HPV types were detected in warts as well as in squamous cell carcinomas. The Southern blot technique confirmed the distribution of HPV types. Group specific viral antigen was detected in 12 lesions, mainly warts. C-Ha-ras oncogene was amplified in 13 lesions and c-myc oncogene in 10 lesions, 9 of which showed both oncogene amplification. The results obtained with in situ hybridization for c-myc gene amplification were confirmed with the Southern blot technique in 11/14 cases. Ras and/or myc amplification was more frequent in squamous cell carcinomas and anogenital papillomas than in warts and actinic keratoses. The amplification was not always linked to the presence of HPV DNA; however, it was more frequent in lesions infected by potentially oncogenic HPV types than in lesions containing only benign HPV types. Myc and p21 oncoproteins were respectively localized in the nucleus and on the membrane of epithelial cells by immunofluorescence. Most lesions showed a good concordance between the detection of oncogene DNA and proteins. Our results suggest than c-Ha-ras and c-myc cellular oncogenes' activation and HPV infection could play a role in the cancerization of cutaneous lesions from transplant recipients.

Genes, myc↗
PubMed1992

[Anti-polynuclear neutrophil cytoplasmic antibodies of the perinuclear type or p-ANCA].

Some neutrophil cytoplasmic auto-antibodies produce perinuclear immuno staining of alcohol-fixed neutrophils called P-Anca pattern. These autoantibodies show chiefly reactivity with myeloperoxidase in Elisa but other specificities have been detected (elastase, cathepsin, lactoferrin). These P-Anca anti-MPO are more frequent with renal angiitis but P-Anca (anti-MPO negative) are associated with other diseases without renal failure (rheumatoid arthritis, Gougerot-Sjogren and ulceritis colitis).

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1992

Effect of epidermal growth factor on ornithine decarboxylase activity and urea synthesis in isolated rat hepatocytes.

Ornithine decarboxylase (ODC) activity is induced by protein-synthesis independent mechanisms in freshly isolated rat hepatocytes, incubated either without or with a mixture of amino acids in the incubation medium. Urea synthesis rates were two- to three-fold higher in those hepatocytes incubated in the presence of amino acids that in those lacking amino acids in the medium. Epidermal growth factor (EGF) delayed ODC induction, but only in the presence of amino acids. EGF significantly decreased ureagenesis when hepatocytes were incubated in the presence of amino acids and only endogenous substrates were available. No evidence of any link between ODC induction and urea synthesis was found.

Amino Acids↗
PubMed1991

Effect of epidermal growth factor (EGF) on gluconeogenesis in isolated rat hepatocytes. Dependency on the red-ox state of the substrate.

It was found that EGF decreased both the basal- and the glucagon-stimulated gluconeogenesis from lactate alone or from a high lactate/pyruvate ratio and that it enhanced both the basal- and the glucagon-inhibited glucose synthesis from pyruvate alone or from a low lactate/pyruvate ratio. These findings demonstrate that the effect of both EGF and glucagon on glucose production by isolated hepatocytes depends on the red-ox state of the substrate.

Animals↗
PubMed1991

Mismatch between radionuclide and contrast angiography in the assessment of the perfusion of a transplanted kidney.

When early complications occur after a kidney transplant, radionuclide angiography may be useful in determining a possible vascular origin. The authors describe the case of a patient with anuria continuing 24 hours after transplantation. Radionuclide angiography showed a defect at the site of the renal graft, suggestive of arterial or venous thrombosis. Contrast angiography was performed immediately but showed no vascular abnormality; neither did radionuclide angiography performed the next day. The authors concluded that a spasm at the site of the renal artery anastomosis, overcome by contrast angiography, could explain this phenomenon.

Adult↗
PubMed1991

Involvement of catecholamines in the effect of fasting on hepatic endothelial lipase activity in the rat.

The effect of fasting on hepatic endothelial lipase activity in the liver of adult rats was investigated. We found that, both in male and female rats, fasting produced a progressive decrease of the hepatic endothelial lipase activity. Upon refeeding, the activity returned to control values in 48 h. In isolated livers from fed male rats, a sharp peak of hepatic endothelial lipase activity appeared in the perfusate upon heparin addition. It accounted for 75% of the total activity (heparin-released + residual) of the tissue. Fasting (24 h) decreased the heparin-releasable activity, and this effect was responsible for most of the decrease found in whole tissue. We suggest that the effect might be due to a decreased synthesis and/or secretion of the enzyme by hepatocytes, since isolated hepatocytes from fasted rats, incubated at 37 C, released 65% less activity to the incubation medium than hepatocytes from fed rats. Adrenaline, but not insulin, glucagon, dexamethasone, epidermal growth factor, or T3, decreased the amount of hepatic endothelial lipase activity released by hepatocytes isolated from fed rats. The effect of adrenaline appears to be mediated by alpha 1-receptors since phenylephrine but not isoprenaline reproduced, and prazosin but not propranolol blocked, the effect of the catecholamine. In the presence of cycloheximide, adrenaline also decreased the amount of activity released. We suggest that, in our incubation conditions (up to 3 h), the hormone affects the posttranslational processing of the enzyme. In vivo administration of prazosin blocked the effect of both noradrenaline and fasting on hepatic endothelial lipase activity in whole liver. Those results suggest that catecholamines are involved in the decreased hepatic endothelial lipase activity found in the liver of fasted rats, and points out the role of these hormones in the acute modulation of an enzyme involved in reverse cholesterol transport.

Animals↗