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C Brunet

Publications and source records attributed to C Brunet.

At least 19 recordsLinked to original sources
PubMed2002

Effects of Rosa canina fruit extract on neutrophil respiratory burst.

Respiratory burst leads polymorphonuclear neutrophils (PMN) to produce reactive oxygen species (ROS) such as superoxide anions (O(2)(o-)), hypochlorous acid (HOCl) and hydrogen peroxide (H(2)O(2)) which may possess deleterious effects for the organism. Rosa canina fruits are well known to contain a large amount of vitamin C which is antioxidant. This study was focused on the polyphenolics contained in rose hips to evaluate their antioxidative properties. We prepared a rose hip extract deprived of vitamin C. The extract contained mainly phenolics such as proanthocyanidins and flavonoids. We investigated its effects directly against (O(2)(o-)), HOCl and H(2)O(2) and investigated its effects on isolated PMN. For that, in vitro inflammatory conditions were reproduced by stimulating PMN with stimuli having different transductional pathways, in order to determine a possible mechanism of action. The results showed that the extract can inhibit ROS tested in acellular and cellular systems. The IC(50) obtained were 5.73 mg/L, 1.33 mg/L and 2.34 mg/L respectively for (O(2)(o-)), HOCl and H(2)O(2) in acellular experiments. For cellular experiments, the IC(50) were quite similar. Thus, the extract did not present an effect on PMN metabolism. Therefore, the antioxidative effects of Rosa canina are due not only to vitamin C but also to polyphenolics.

Anthocyanins↗
PubMed2002

[Cephalic pancreaticoduodenectomy for adenocarcinoma of the head of the pancreas: does pylorus preservation change morbidity and prognosis?].

STUDY AIM: To evaluate the influence of a pylorus-preserving on the morbidity and prognosis of patient with pancreaticoduodenectomy for adenocarcinoma of pancreas. PATIENTS AND METHODS: Between 1985 and 1999, 183 patients were operated on for pancreatic adenocarcinoma. Among them, 63 patients (40 men, mean age 63 years, range 41-77 years) had curative resection and were included in this retrospective study. They were classified according to the type of resection. In the group I, the procedure included a pylorus-preserving pancreaticoduodenectomy (n = 35). In the group II, the procedure included polar inferior gastrectomy (n = 28). The prognosis was compared. Parameters for comparison were rate of local recurrence, rate of metastatic evolution and duration of survival. RESULTS: The operative length and mortality rate (group I: 0%, group II: 3%), general (p = 0.37) and specific morbidity (p = 0.30), frequency of delayed gastric emptying were similar in the 2 groups (group I: 20%, group II: 35%, p = 0.88). The duration of naso-gastic aspiration was shorter in the group I (6 days vs 8, p = 0.01). The prognosis was the same in the 2 groups (metastasis: group I: 39%, group II: 56%, p = 0.12, local recurrence: group I: 58%, group II: 43%, p = 0.09, mean survival: group I: 18 months, group II: 19 months, p = 0.77). CONCLUSION: These results suggest that pylorus preserving pancreatoduodenectomy could be performed for patients with adenocarcinoma of the head of the pancreas and does not compromise survival.

Adenocarcinoma↗
PubMed2002

[Retrospective study of 55 patients with circulating blood T gama/delta lymphocytosis].

PURPOSE: Gamma/delta T lymphocytes constitute a singular population due to their particular antigenic recognition and their localization inside the epithelium. Their functions are complementary to those of the alpha/beta T-cells and they are involved in the defense and regulation of the immune system. Their role in human diseases is not very well understood and the aim of our study was to analyze a population of patients with a peripheral gamma/delta T-cell lymphocytosis. METHODS: The study included 55 patients, recruited from 1997 to 2000, with a peripheral gamma/delta T lymphocytosis (defined by a proportion of gamma/delta T-cells of over 10% of total peripheral T lymphocytes). Analysis of the lymphocyte population was obtained by cytometry after peripheral blood sampling. RESULTS: Three main groups of diseases were observed: infectious diseases (viral infections and tuberculosis), inflammatory diseases (sarcoidosis and autoimmune diseases) and blood diseases (monoclonal gammopathies and hemopathies). Persistence of gamma/delta T lymphocytosis was dependent on the underlying disease (transitional when associated with an infectious disease and lasting when associated with sarcoidosis). The rest of the immunophenotyping analysis was usually normal. CONCLUSION: Our results confirm the data published in the literature concerning the role of the gamma/delta T lymphocytes in infectious, inflammatory and autoimmune diseases and neoplasias. These data are in agreement with the cytotoxic and regular functions of these lymphocytes.

Adolescent↗
PubMed2002

Analysis of donor NK and T cells infused in patients undergoing MHC-matched allogeneic hematopoietic transplantation.

We retrospectively analyzed the percentages and absolute numbers of T cells, natural killer (NK) cells and NK cell subsets in cryopreserved samples of either bone marrow or blood non-T cell-depleted allogeneic MHC-matched hematopoietic grafts. Using flow cytometry, we found higher numbers of NK cells in aphereses than in bone marrow collections. We further investigated the distribution of NK cell subsets, defined by the cell surface expression of MHC class I-specific receptors, in these allogeneic grafts. The distribution of NK cell subsets from the two different origins were similar, with the exception of the CD158a/h(+) NK cell subset, whose size appeared to be smaller in bone marrow. The search for relations between the numbers of infused cells and post-transplantation events demonstrated that increasing numbers of infused T cells but not NK cells are related with decreased overall survival. Our study highlights the toxicity of infused T cells but not NK cells in allogeneic MHC-matched hematopoietic grafts. These data pave the way for further trials to investigate the effect of NK cell infusion in MHC-matched allogeneic transplantation, and in particular whether ex vivo NK cell expansion and activation may enhance the anti-tumoral effect of the procedure and decrease its morbidity.

Adolescent↗
PubMed2001

Comparative study of the leachability of di(2-ethylhexyl) phthalate and tri(2-ethylhexyl) trimellitate from haemodialysis tubing.

The leachability of both Di(2-ethylhexyl) phthalate (DEHP) and Tri(2-ethylhexyl) trimellitate (TEHTM) or Trioctyl trimellitate (TOTM) from haemodialysis tubing was investigated in 20 patients with chronic renal failure undergoing maintenance haemodialysis. The blood tubing made of common polyvinyl chloride (PVC) plasticized with DEHP (group 1 patients) were replaced with tubing plasticized with TOTM-DEHP (group 2 patients). The patient blood obtained from the inlet and the outlet of the dialyzer was analyzed during a 4 h-dialysis session. Thus, the circulating concentrations of both DEHP and TOTM resulting from the release from dialyzer tubes were estimated using High-performance Liquid chromatograph (HPLC). With the common PVC-DEHP blood tubing, a DEHP quantity of 122.95+/-33.94 mg was extracted from tubing during a single dialysis session (ranging from 55 to 166.21 mg). During the same period, the total amounts of DEHP retained by the patients were 27.30+/-9.22 mg (ranging from 12.50 to 42.72 mg). As for blood tubing plasticized with TOTM-DEHP, 41.80+/-4.47 mg of DEHP and 75.11+/-25.72 mg of TOTM were extracted. During the same period, the amounts of DEHP and TOTM retained by the patients were 3.42+/-1.37 mg and 4.87+/-2.60 mg, respectively. The extraction rate both plasticizers was correlated with serum lipid content (cholesterol+triglyceride) (r(2)=0.75 for DEHP and r(2)=0.64 for TOTM). In the present investigation, less TOTM and DEHP were apparently released from haemodialysis tubing plasticized with TOTM-DEHP than DEHP released from haemodialysis tubing plasticized with DEHP only. TOTM seems to be a superior alternative to DEHP for use in medical devices because of its potential lower leachability. To recommend it as an alternative plasticizer, its possible toxicity towards human body should be investigated before it can be used routinely. However, patients undergoing haemodialysis using tubing plasticized with DEHP only are regularly exposed to non negligible amounts of DEHP. In view of several biological effects previously reported, it is time to reconsider the use of DEHP only as a plasticizer.

Adult↗
PubMed2001

High-performance liquid chromatographic method for the determination of di(2-ethylhexyl) phthalate in total parenteral nutrition and in plasma.

A simple, rapid and sensitive reversed-phase high-performance liquid chromatographic method with UV detection was developed for the quantification of di(2-ethylhexyl) phthalate (DEHP) in parenteral nutrition admixtures containing fat emulsion and in plasma samples of children daily treated by total parenteral nutrition. The analyte and the internal standard, di-n-heptyl phthalate, were extracted twice using hexane and the organic layer separated and dried under nitrogen. The residues were reconstituted with acetonitrile and 20 microl was injected into a Waters Spherisorb C18 column, the UV detector was set at 202 nm. The mobile phase was acetonitrile-aqueous buffer (triethylamine 0.08% adjusted to pH 2.8 with 1 M phosphoric acid) mixture (88:12, v/v) and it was pumped at 1 ml/min. Average recoveries were 97% or greater. This method was successfully used to investigate the amounts of DEHP which can leach from bags and tubing into fat emulsion and which could contaminate children under long-term parenteral nutrition. On the other hand, the circulating DEHP concentrations were estimated in four children under regular long-term parenteral nutrition.

Child↗
PubMed2001

Investigation of the inhibitory effects of chelerythrine chloride on the translocation of the protein kinase C betaI, betaII, zeta in human neutrophils.

The protein kinase C (PKC) is a serine/threonine kinase, consisting of different isoforms, implicated in numerous processes of signal transduction. To understand this enzyme well, different pharmacological tools were developed. To activate PKC specifically, phorbol esters were previously used but recent research has shown that these compounds are able to stimulate other proteins. Our model is the respiratory burst in the polymorphonuclear neutrophils. A decrease in the inflammatory process was measured using chelerythrine chloride. Action on PKC was proved by a binding study and by showing the absence of translocation of this enzyme from the cytoplasm to the plasmic membrane during stimulation.

Alkaloids↗
PubMed2001

Investigation of the inhibitory effects of HA-1077 and Y-32885 on the translocation of PKCbetaI, PKCbetaII and PKCzeta in human neutrophils.

To transmit the information inside the cell, one possibility is the action of an enzyme called kinase that phosphorylates other proteins. To study these enzymes, chemical compound synthesis was needed to know the function and the mechanism of activation. The major difficulty is creating a specific molecule for one kinase. In this study, we test the action of Rho-kinase inhibitors (HA-1077 and Y-32885) on protein kinase C (PKC) in the respiratory burst in the human polymorphonuclear neutrophils. We have shown that these compounds could inhibit the anion superoxide production. To prove their action on PKC, we have shown a decrease of binding of a specific ligand (phorbol-12,13-dibutyrate) with each inhibitor. During its activation, PKC was translocated from the cytoplasm to the plasmic membrane. We have also shown an inhibition of this translocation, proving an inhibition of PKC by HA-1077 and Y-32885.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed2000

High-performance liquid chromatographic determination of naltrexone in plasma of hemodialysis patients.

A simple, sensitive, selective and reliable reversed-phase high-performance liquid chromatographic (HPLC) method with UV detection is described for the determination of naltrexone in plasma samples. Naltrexone and the internal standard, naloxone, were isolated from plasma either with a liquid-liquid extraction method using ethyl acetate or with a solid-phase extraction method using Sep-Pack C18 cartridge before chromatography. The extracts were dried under a stream of nitrogen and the samples were reconstituted in the mobile phase, then 20 microL were injected on a Waters Symmetry C18 column (5 microm particle size, 4.6 x 150 mm). The mobile phase consisted of 0.06% triethylamine (pH 2.8)-acetonitrile (92:8, v/v) pumped at 1 mL/min. The peak-area ratio versus plasma concentration was linear over the range of 10-500 ng/mL and the detection limit was less than 8 ng/mL. Quantification was by ultra-violet detection at 204 nm. The present method was applied to the determination of the plasma concentration of naltrexone in dialyzed patients. Patients (n = 8) with severe generalized pruritus received 50 mg of naltrexone orally per day for 2 weeks. The variability in the therapeutic response in treated patients required plasma concentration investigations of this opioid antagonist.

Chromatography, High Pressure Liquid↗
PubMed2000

Serial anatomy of the larynx in MRI: MRI-histologic correlations.

The larynx is an organ with a complex anatomic structure. MRI allows the performance of sections in the three planes of space, so that this study of the soft parts of the larynx yields results superior to those of other imaging techniques. Together with laryngoscopy, MRI is most often used in assessing the extension of malignant laryngeal tumors. This assessment is fundamental in choosing the indications for surgery, but the published reports of MRI of the larynx are sometimes discordant. The visualization of certain important anatomic structures such as the conus elasticus is uncertain. Our aim was to study the MRI radio-anatomy of the larynx based on correlations between MRI and histologic sections. Eight anatomic specimens were studied: four in the transverse plane, two in the sagittal plane, and two in the frontal plane. The MRI and histologic sections made at the same levels were compared. These comparisons allowed a description of the sectional radio-anatomy of the larynx and an assessment of the reliability and limitations of MRI. All the major anatomic structures could be identified. It was possible to demonstrate the conus elasticus. We were able to visualize the vocal process of the arytenoid cartilage, which has not to our knowledge been previously described in the literature.

Aged↗
PubMed2000

Intestinal retractor for transperitoneal laparoscopic aortoiliac reconstruction: experimental study on human cadavers and initial clinical experience.

BACKGROUND: We set out to design a bowel retractor for use during laparoscopic transperitoneal reconstruction of the infrarenal aorta and of both iliac axes. METHODS: This study was performed on five cadavers. After the insertion of four trocars, a pneumoperitoneum was created, and the bowels were gathered to the right flank. On each cadaver, the following four measurements were made: the distance between the Treitz angle and the aortic bifurcation (L1), the distance between the aortic bifurcation and the right internal inguinal ring (L2), the angles between L1 and L2 in the axial plane (A1), and the angles between them in the sagittal (A2) plane. These measurements enabled us to create a bowel retractor. The device was composed of a malleable metallic rod with a 2.5-mm diameter that was fixed to the operating table and whose intraabdominal section was designed to follow the outline of the mesenteric root in addition, a 25 x 12 cm polypropylene net was slipped around the rod. The infrarenal aorta and both iliac axes were then dissected. Secondarily, the bowel retractor was used in eight patients (seven men and one woman; mean age, 56 years; range 44-76) during laparoscopic aortoiliac reconstruction for occlusive (n = 6) or aneurysmal (n = 2) disease. RESULTS: The statistical analysis of the measurements performed on cadavers showed a significant correlation between body height and L1 (r = 0.8769; p < 0.05) and L2 (r = 0. 9706; p < 0.01) distances. It was then possible to design the shape of two metallic rods (one small and one large) so that they would be adaptable to the height of the patients (<1.65 m and >1.65 m). During our clinical experience, all laparoscopic procedures were completed in a mean operative and clamping time of 266 min (range, 215-360) and 54 min (range, 18-90), respectively. Mean postoperative hospital stay was 6 days (range, 3-13). CONCLUSION: Our experimental study allowed us to develop a bowel retractor that can make it easier to perform laparoscopic transperitoneal aortoiliac reconstruction in humans.

Adult↗
PubMed2000

[Perineal gangrene: new bacteriologic approach. Results of medico-surgical treatment (81 cases)].

STUDY OBJECTIVE: The objective of this retrospective study was to report the results of a series of 81 cases of perineal gangrene treated in the same center. PATIENTS AND METHODS: From 1988 to 1998, 81 patients (64 males, 17 females, mean age: 58 years) with perineal gangrene were treated by a medico-surgical team, by means of a protocol combining appropriate intensive care measures based on a new bacteriologic concept of infectious agents, extensive excisions and drainage of the infraperitoneal region and hyperbaric oxygen therapy. RESULTS: The mortality rate was 24.7%. Mean duration of intensive care stay was 19 days, mean duration of hospital stay was 31 +/- 4 days (range: 6 to 60 days). Risk factors were: age > 68 years (p = 0.001), shock (p = 0.83), subcutaneous crepitation (p = 0.25) and severity index > 10 (p = 0.003). Sequelae were anal incontinence (n = 3) and permanent colostomy (n = 5). Secondary plastic reconstruction was necessary in four patients. There were no urologic or genital sequelae. CONCLUSION: Perineal gangrene is still a very serious disease. The time to treatment, the simplified severity index and consideration of bacteriologic combinations are the main prognostic factors.

Aged↗
PubMed2000

Phenolic compounds and antioxidant activities of buckwheat (Fagopyrum esculentum Moench) hulls and flour.

The interest of polyphenolics as therapeutic agents against diseases involving radical damage is growing. The phenolic contents of the hulls and flour from the seeds of Fagopyrum esculentum (French variety 'La Harpe') (total phenols, flavonoids, total flavanols, oligomeric proanthocyanidins) are compared with the antioxidative effects of the extracts against reactive oxygen species: hydrogen peroxide, hypochlorous acid, superoxide anion. The higher efficiency of the flour extract can be related to its higher flavanolic content rather than to flavonoids which are predominant in the hull extract.

Anthocyanins↗
PubMed2000

A pharmacokinetic interpretation of increasing concentrations of DEHP in haemodialysed patients.

The degree of exposure to DEHP was assessed in 11 patients with chronic renal failure undergoing maintenance haemodialysis. The amount of DEHP leached from the dialyser during a 4-h dialysis session was estimated by monitoring the DEHP blood concentration using a HPLC method. When a patient undergoes a dialysis treatment, the concentration of di-2-ethylhexyl phthalate (DEHP) in venous blood is increased when the blood crosses through the dialysis apparatus. This increase may be explained either because DEHP is not extracted by the dialyser or because DEHP comes from the dialysis bath due to contact of blood against plasticized pipes. To explain the increasing concentration of DEHP during treatment of renal failure using plasticized tubing, we propose a pharmacokinetic compartmental model in order to fit raw data obtained from dialysed patients and to get the amount of DEHP which enters the body by AUC calculations. Results obtained after HPLC analysis show a high degree of interpatient variability in DEHP retained. This amount can reach a toxicity level because of repetitive dialysis treatments over prolonged periods of time. In the coming years, it seems necessary to reconsider the use of DEHP as a plasticizer in medical devices. Highly unacceptable amounts of DEHP leached during the dialysis session could be easily avoided by careful selection of haemodialysis tubing.

Adult↗
PubMed2000

Reduced ammonium chloride haemolysis time enhances the number of isolated functional rabbit polymorphonuclear neutrophils.

In the present study we compared seven different methods for isolating rabbit polymorphonuclear neutrophils (PMNs) with a view to assessing viability, lymphocyte contamination and isolation yield. The two methods offering the best isolation yield and functional PMNs were retained. Leukocyte-containing plasma fraction was obtained after erythrocyte sedimentation with dextran. First, PMNs were isolated from this fraction, using hypotonic ammonium chloride haemolysis followed by Histopaque density gradient centrifugation (Method-A). Second, PMNs were obtained from leukocyte-containing plasma after centrifugation on two Percoll layers (Method-B). These processes resulted in a high cellular yield: 2.66x10(6)+/-0.22 PMNs per ml of blood (Method-A) and 1.87x10(6)+/-0.37 PMNs per ml of blood (Method-B). In both cases the PMNs isolated were of high purity and viability. In comparison, when using the standard techniques for rabbit - consisting of ammonium chloride haemolysis taking at least four times as long--fewer PMNs were isolated. The PMNs isolated by Method-A and -B were able to generate a high amount of reactive oxygen species (ROS) after stimulation with phorbol 12-myristate 13-acetate (PMA). These methods to separate PMNs are recommended for in vitro studies.

Ammonium Chloride↗
PubMed2000

Immune reconstitution and outcome after unrelated cord blood transplantation: a single paediatric institution experience.

We report the outcome of 12 children who underwent unrelated cord blood transplant (U-CBT) in a single institution between February 1997 and July 1998. The 1 year event-free survival was 67% (95% CI of 26%). Four children died with infectious complication as cause of death in three cases. Immune reconstitution was studied during first year post transplant by assaying total lymphocyte counts, B cells, NK cells and T cell subsets in the eight disease-free surviving patients. We observed a prompt recovery of CD19+ cell number which was greater than 500/microl at 9 months for all patients except the one with severe cGVHD. B cells constituted the predominant lymphocyte subset at 6 and 9 months post transplant with normal or elevated B cell numbers according to normal paediatric range. We noted normal serum immunoglobulin levels at 6 months post transplant for IgA and IgM and at 9 months for IgG. The CD3+ cell count and particularly the CD3+CD8+ T cell subset remained depressed until 12 months post transplant. Six months after unrelated CBT, seven out of eight patients had less than 100 CD3+CD8+ cells/microl. CD3+CD4+ cell recovery was less impaired with all children achieving an absolute count of CD3+CD4+ cells greater than 200/microl during the first year in a median of 5 months. The percentage of NK cells was elevated during the first 6 months after CBT but their absolute count remained within the normal range. Bone Marrow Transplantation (2000) 25, 53-57.

Adolescent↗
PubMed2000

Impact of highly active anti-retroviral therapy (HAART) on cytokine production and monocyte subsets in HIV-infected patients.

HIV infection is associated with cytokine production by monocytes and expansion of a monocyte subset that expresses high levels of CD16. Our study was designed to investigate the effects of anti-retroviral therapies on these immune parameters. Four groups of HIV+ patients were included in the study. The first group comprised drug-naive patients (n = 20); the second included patients who received two inhibitors of HIV reverse transcriptase (n = 45); the third group received a therapy combining these two inhibitors and one inhibitor of HIV protease (HAART) (n = 35); the fourth consisted of patients who had stopped their treatment (n = 20). The release of inflammatory cytokines (tumour necrosis factor, IL-1beta, IL-6) and immunoregulatory cytokines such as IL-10 by monocytes was determined by ELISA. The monocyte subsets expressing low or high levels of CD16 were studied by flow cytometry. Monocytes from patients naive of treatment released higher amounts of inflammatory cytokines and IL-10 than HIV- individuals. Each anti-retroviral therapy restored a normal pattern of cytokine secretion. Nevertheless, the release of cytokines increased again after the arrest of the treatment. The expansion of the monocyte subset that expresses high levels of CD16 was significantly decreased by HAART but not by the treatment including two inhibitors of reverse transcriptase. These results suggest that only HAART controls monocyte activation in the treatment of HIV infection.

Adult↗