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P Bernard

Publications and source records attributed to P Bernard.

At least 19 recordsLinked to original sources
PubMed2002

[Techniques, indications and early results of splenic preservation during left pancreatectomy].

STUDY AIM: Splenic preservation is rarely performed during left pancreatectomy. We compared retrospectively the early results of left pancreatectomy with and without splenic preservation to define the place of this procedure. PATIENTS AND METHODS: From 1979 to 1997, among 54 left pancreatectomies for another indication than adenocarcinoma, 13 were performed with and 41 without splenic preservation. The technique used for splenic preservation was prograde dissection of the left pancreas with (n = 4) and without (n = 9) preservation of both splenic artery and vein. The preoperative characteristics of the patients, peroperative data, postoperative morbidity and length of stay were compared. RESULTS: Mean operative time was longer with splenic preservation (262 +/- 67 min versus 215.6 +/- 59 min, p < 0.05), particularly in case of splenic vessels preservation (295 +/- 38 min, p < 0.02) whereas no difference was noted with splenic vessels ligation (240 +/- 76 min, p > 0.05). No mortality occurred. Prevalence of preoperative or postoperative haemorrhage, morbidity, or length of stay (intensive care unit and whole hospitalisation) did not differ with or without splenic preservation. Five patients developed pancreatic fistula without influence of splenic preservation: 1/13 (7.7%) versus 4/41 (9.7%); conversely, surgery following acute pancreatitis was associated with an higher risk of pancreatic fistula: 3/5 versus 2/49 (p < 0.005). No splenic necrosis occurred after splenic preservation. CONCLUSION: During left pancreatectomy, splenic preservation increases the operative duration (only in case of preservation of splenic vessels) but does not increase morbidity. This technique should be used whenever possible to allow long term immunological benefits of splenic preservation.

Acute Disease↗
PubMed2002

Preliminary screening of some tropical plants for anti-tyrosinase activity.

In our efforts to find new active tyrosinase inhibitors for skin-whitening or antibrowning preparations, we investigated 67 tropical plants belonging to 38 families, which were evaluated for their anti-tyrosinase activity. The results of our investigation show that extracts of 5 plants, Stryphnodendron barbatimao, Portulaca pilosa, Cariniana brasiliensis, Entada africana and Prosopis africana present interesting in vitro mushroom tyrosinase inhibition (over 90%), similar to a positive control: Morus alba. These 5 plants will be studied in order to isolate and identify phytochemical compounds, involved in this biological activity.

Agaricales↗
PubMed2002

[Hospitalization criteria for erysipelas: prospective study in 145 cases].

INTRODUCTION: Two recent studies conducted in France among general practitioners have shown that they only hospitalized between 20 to 50 percent of patients with erysipelas seen in private practice. We therefore conducted a hospital-based, prospective study designed to determine the hospitalization criteria for erysipelas, since a number of patients are also hospitalized directly through the emergency department. PATIENTS AND METHODS: This prospective, hospital-based study, included patients hospitalized for clinical diagnosis of erysipelas in 9 centres in north-eastern France. Clinical data were recorded using a standard questionnaire filled-in during the first 72 hours of hospitalization. They included: demographic (name and first name initials, age, sex) and clinical (location of erysipelas) characteristics, as well as the origin of the patient (home, emergency department, other department), the reasons for hospitalization (severity of local or systemic signs, suspicion of deep vein thrombosis, location on the face, age over 60 years, associated diseases, absence of improvement after ambulatory treatment, socioeconomic reasons or on principle hospitalization). Patients hospitalized by (or without) a general practitioner were compared using Chi-2 and Student t tests. RESULTS: One hundred forty-five adults (80 women and 65 men; mean age 61 +/- 20 years) were included in the study: 89 patients (61 p. 100) were hospitalized by a general practitioner whereas 56 (39 percent) went directly to the emergency department. In 128/145 cases (88 p. 100), erysipelas was localized on the lower limbs. The mean number of reasons for hospitalization per patient was of 2.2 +/- 1.2. The most frequent reason for hospitalization was an associated disease (diabetes, obesity, alcoholism, immunodeficiency), present in 77 cases (53 p. 100). Patients hospitalized through a general practitioner were older than those hospitalized directly through the emergency department (68 vs 51 years; p<0.001). Patients hospitalized by a general practitioner more frequently had an erysipelas located on the lower limbs (94 p. 100 vs 79 p. 100; p<0.001) and the mean number of reasons for hospitalization was greater (2.4 vs 1.7; p<0.001), especially suspicion of deep vein thrombosis and elevated mean age. The treatment started during hospitalization was intravenous penicillin G in 67 cases (46 p. 100), oral pristinamycin in 28 cases (19 p. 100) and intravenous or oral amoxicillin in 9 cases (6 p. 100). COMMENTS: This study demonstrates the existence of two distinct courses of hospitalization for erysipelas. Patients hospitalized by a general practitioner were older and their erysipelas more frequently located on the lower limbs and deep vein thrombosis was suspected. Our study also shows the emergence of a population of patients younger and without medical supervision, for whom the general practitioner is replaced by the emergency department of the local hospital. Nevertheless, the most frequent reason for hospitalization in both groups is the existence of an associated disease, possibly responsible for further complications.

Adult↗
PubMed2002

[Malignant blue nevus: clinicopathologic study with AgNOR measurement. Seven cases].

BACKGROUND: Malignant blue nevus is a very rare tumor. Argyrophilic nucleolar organizer regions (AgNORs) have been reported to be both a diagnostic and prognostic clue in various tumors, especially if standardized using an image analysis systems. PATIENTS AND METHODS: Seven cases of malignant blue nevus were retrospectively recorded between 1974 and 1999, and their clinical and pathological features described. Using an image analysis system, AgNOR measurements were studied in all cases. These results were compared with those obtained in 10 cases of commun blue nevus, 10 cases of cellular blue nevus and 10 cases of malignant melanoma. RESULTS: The most frequent location of malignant blue nevus was the scalp. Clinically, the tumor generally consisted of a blue nodule, 2.5 cm in diameter. There was no single histopathological criterion for the diagnosis of malignant blue nevus. AgNOR measurement was significantly higher in malignant blue nevus in comparison with commun blue nevus (p<0.0004) or cellular blue nevus (p<0.012), whereas there was no difference between malignant blue naevus and malignant melanoma (p > 0.50). DISCUSSION: Our results confirm the severe prognosis of malignant blue nevus and highlight the necessity of removing all blue tumours located on the scalp. AgNOR measurement using an image analysis system appears to be a useful tool for the diagnosis of malignant blue nevus, but further studies remain necessary.

Adolescent↗
PubMed2002

[Positive photobiological investigation in Jessner's lymphocytic infiltration of the skin].

BACKGROUND: Jessner's lymphocytic infiltration of the skin is a rare and benign disorder. Its clinical course is cyclic with remissions and exacerbations. In this disease, photosensitivity was previously noticed by authors and recently demonstrated. We report four new cases with positive photobiological investigation. CASE REPORTS: Four patients (2 males, 2 females), with a mean age 36 years were seen with erythematous papules or discoid plaques on face, arms and upper trunk. The onset of disease occurred after sun exposure in summer. Skin biopsies showed perivascular lymphocytic infiltration in the dermis. All patients relapsed cyclically with incomplete healing during winter. Photobiological investigation elicited skin lesions in a broad spectrum of UV: UVB (2 cases), UVA (1 case), UVA and UVB (1 case). In all patients treatment with oral antimalarials and external photoprotection was effective. DISCUSSION: Our data suggest that photosensitivity history in patients with Jessner's lymphocytic infiltration of the skin should be searched for, and confirmed by provocative phototesting. This relevant event could guide the therapeutic strategy because antimalarials were effective for the Jessner's lymphocytic infiltration cases with photosensitivity.

Adult↗
PubMed2001

Cumulative influence of matrix metalloproteinase-1 and -2 in the migration of melanoma cells within three-dimensional type I collagen lattices.

During melanoma progression, migrating cells must cross human dermis, a type I collagen-rich tissue. We have show that MMP-1 and MMP-2 act in a cumulative manner in the in vitro invasion of a three-dimensional type I collagen matrix by melanoma cells. Two melanoma cell lines (M1Dor and M3Da) previously reported to secrete proMMP-2 in a direct relationship with their tumorigenic potential into nude mice were used (F. Capon et al., 1999, Clin. Exp. Metastasis 17, 463-469). The highly tumorigenic cell line (M3Da) displayed a five-fold faster migration rate in type I collagen matrix, compared to its lower tumorigenic counterpart (M1Dor). In parallel, activation of proMMP-2 was evidenced in M3Da- but not M1Dor-populated collagen lattices. Such enzyme activation was associated with a significant decrease in TIMP-2 and TIMP-1 production. Agents known to interfere with proMMP-2 activation, i.e., excess TIMP-2, furin convertase inhibitor, and alphavbeta3 blocking antibody, reduced by 30-40% the type I collagen invasive capacity of M3Da cells. By comparison, batimastat, a wide-spectrum MMP inhibitor, exhibited a more pronounced inhibitory effect (>70%). It suggested that other collagenases than MMP-2 could participate in type I collagen invasion. Collagenase-3 (MMP-13) was produced at low levels by melanoma cells whatever the cell culture conditions. In contrast, M3Da and M1Dor cells secreted collagenase-1 (MMP-1) following 48 h of culture on plastic dishes. Growing melanoma cells in type I collagen gel did not modify enzyme production, but induced proMMP-1 activation in M3Da but not M1Dor cell-populated lattices. Blocking the plasmin-mediated proMMP-1 activation by aprotinin inhibited type I collagen gel invasion by 30%. Since the combination of aprotinin and furin convertase inhibitor reduced collagen invasiveness by melanoma cells to a level comparable to that attained with batimastat, we conclude that both MMP-2 and MMP-1 are involved in such tissue invasion.

Animals↗
PubMed2001

Requirement of heterochromatin for cohesion at centromeres.

Centromeres are heterochromatic in many organisms, but the mitotic function of this silent chromatin remains unknown. During cell division, newly replicated sister chromatids must cohere until anaphase when Scc1/Rad21-mediated cohesion is destroyed. In metazoans, chromosome arm cohesins dissociate during prophase, leaving centromeres as the only linkage before anaphase. It is not known what distinguishes centromere cohesion from arm cohesion. Fission yeast Swi6 (a Heterochromatin protein 1 counterpart) is a component of silent heterochromatin. Here we show that this heterochromatin is specifically required for cohesion between sister centromeres. Swi6 is required for association of Rad21-cohesin with centromeres but not along chromosome arms and, thus, acts to distinguish centromere from arm cohesion. Therefore, one function of centromeric heterochromatin is to attract cohesin, thereby ensuring sister centromere cohesion and proper chromosome segregation.

Cell Cycle Proteins↗
PubMed2001

Rat olfactory bulb and epithelium UDP-glucuronosyltransferase 2A1 (UGT2A1) expression: in situ mRNA localization and quantitative analysis.

UDP-glucuronosyltransferases (UGTs) form a multigenic family of enzymes involved in the biotransformation and elimination of numerous endo- and xenobiotic compounds. Beside the diverse UGT isoforms present in the liver as well as in other tissues, the UGT2A1 isoform, also called olfactory UGT, was initially thought to be expressed in the nasal epithelium only. In this work, we demonstrate the UGT2A1 mRNA expression in the olfactory bulb, using in situ hybridization and quantitative reverse transcription-polymerase chain reaction (RT-PCR) techniques. Within the epithelium, UGT2A1 mRNA is mainly found in the sustentacular cells and to a lesser extent in Bowman's gland cells. Moreover, in situ hybrization staining reveals UGT2A1 mRNA expression in the olfactory sensory neuron nuclei. Neuronal localization of UGT2A1 mRNA within the olfactory bulb is mainly found in the deeper granular cells. The development of the quantitative multistandard RT-PCR method firstly required characterization of the mouse Ugt2A1 cDNA by rapid amplification of cDNA ends (RACE)-PCR. UGT2A1 mRNA levels appear quantitatively six-fold lower in the olfactory bulb than in the epithelium, in both the rat and mouse. The expression of UGT2A1 in the olfactory bulb, which directly connects the nasal epithelium to the brain, emphasizes the potential role of this enzyme in the protection of the brain against airborne hazardous chemicals.

Air Pollutants↗
PubMed2001

Molecular modeling of the GABA/GABA(B) receptor complex.

A three-dimensional model of the extracellular domain of the GABA(B) receptor has been built by homology with the leucine/isoleucine/valine-binding protein. The complete putative GABA-binding site in the extracellular domain is described in both the open and closed states. The dynamics of the "Venus flytrap" mechanism has been studied, suggesting that the molecular dipole moments play a key role in GABA binding and receptor activation. Important residues putatively implicated either in ligand binding or in the dynamics of the receptor are pinpointed, thus highlighting target residues for mutagenesis experiments and model validation.

Amino Acid Sequence↗
PubMed2001

Double common bile duct with ectopic drainage into the stomach. Case report and review of the literature.

A rare abnormal biliary tract consisting in a double common bile duct with an ectopic biliary tree draining into the stomach is described. This congenital anomaly, associated with lithiasis in the ectopic duct, was detected for the first time on MR-cholangiopancreatography. Only 23 cases of abnormal biliary drainage into the stomach have been reported in the literature. Embryogenesis and potential risks, such as lithiasis in the ectopic duct and the development of gastric carcinoma, are discussed.

Aged↗
PubMed2001

[Accessory cystic duct discovered by intraoperative cholangiography during cholecystectomy].

The study aim was to report a rare biliary variation detected with an intraoperative cholangiography during a laparoscopic cholecystectomy. After the ligation of the cystic duct, the gallbladder was opacified via an accessory cystic duct flowing into a branch of the right hepatic duct. This accessory cystic duct was clipped and the postoperative course was uneventful.

Cholangiography↗
PubMed2001

Ethnopharmacology and bioinformatic combination for leads discovery: application to phospholipase A(2) inhibitors.

A program combining ethnopharmacology and bioinformatic approaches has successfully been applied on anti-inflammatory activity. (i) An ethnobotanical study allowed the identification of several plants associated with putative anti-inflammatory properties as potential leads. (ii) On the other hand, it is well known that phospholipase A(2) is a target implicated in the pro-inflammatory process. Thus, (iii) some selected plant extracts were experimentally tested on phospholipase A(2). Finally, (iv) these experimental results combined with bioinformatic tools, such as database exploitation and molecular modeling, allowed to suggest that one compound, betulin and its oxidative form betulinic acid, might be responsible of the anti-PLA(2) activity. This suggestion was confirmed experimentally.

Chromatography, High Pressure Liquid↗
PubMed2001

A molecular modeling and 3D QSAR study of a large series of indole inhibitors of human non-pancreatic secretory phospholipase A2.

Automated docking allowing protein-based alignment was performed for a series of 188 indole inhibitors of the human non-pancreatic secretory phospholipase A2 (hnps-PLA2). All the substituted indoles were docked to the crystal structure of hnps-PLA2 and a three-dimensional QSAR model was then established using the CoMFA method. The set of 188 compounds was divided into two subsets, the first one constituting the training set (126 compounds), while the second constituted the test set (62 compounds). The established CoMFA model derived from the training set was then applied to the test set. A good correlation between predicted and experimental activity data allows to validate the 3D QSAR model. A second and global 3D QSAR including all the compounds was established, allowing the creation of the hnps-PLA2 pharmacophore.

Anti-Inflammatory Agents↗
PubMed2001

Protein-based alignment in 3D QSAR of 26 indole inhibitors of human pancreatic phospholipase A2.

An automated docking procedure was applied on a series of 26 reversible and competitive indole inhibitors of human pancreatic phospholipase A2 (hp-PLA2). X-ray data of this enzyme are not available and the structure was then reconstructed exploiting its protein sequence and the crystallographic data of a bovine pancreatic source. The docking data were used to build a three-dimensional quantitative structure-activity relationship (3D QSAR) model, established using the comparative molecular field analysis (CoMFA) method. This model, joined to the previous one developed for the indole inhibitors of human non-pancreatic secretory phospholipase A2 (hnps-PLA2), an enzyme involved in inflammation processes, will allow for the selection of new strong anti-inflammatory drugs with negligible side effects, at least at the level of hp-PLA2.

Animals↗
PubMed2001

[Abnormal catheter mobility in a totally implantable venous access depending on the upright or supine position in an obese patient].

The authors advise on an exceptional complication in a totally implantable venous access and give recommendations on how to avoid this problem. In an obese person, one week after the implantation of a totally implantable venous access, a chest X-ray showed that the catheter was too short. In the operative room, at the time of the second intervention, the radioscopy did not find this anomaly. The subcutaneous injection port was positioned too low. When the patient was in a supine position, the subcutaneous injection port was in the correct position but when she was in an upright position, the breast descended and pulled down the subcutaneous injection port and the catheter.

Catheterization↗