[Acantholytic dermatosis in patients treated by vemurafenib: 2 cases]. / Deux cas de dermatose acantholytique sous vémurafénib.

BACKGROUND: Acantholytic dyskeratosis under BRAF inhibitors are dermatological diseases rarely reported to date. PATIENTS AND METHODS: We report 2 cases of acantholytic dyskeratosis, reaching the trunk and the seborrheic zones, not itchy, appeared one month after the introduction of vemurafenib. The histological analysis was typical of a "Grover-like rash" for the 2 patients. DISCUSSION: The appearance of acantholytic dyskeratosis under vemurafenib, a BRAF inhibitor, seems related with a paradoxical activation of the MAP-kinases pathway and with a growth acceleration of lesions in which RAS mutations of keratinocytes. Theses dermatoses seem also to occur with dabrafenib. CONCLUSION: The patients treated by BRAF inhibitors (vemurafenib and dabrafenib) can present acantholytic dyskeratosis. The arisen of this mild dermatosis does not question, of course, the continuation of the treatment. These cutaneous manifestations can be managed with emollients.

Management of pain associated with debridement of leg ulcers: a randomized, multicentre, pilot study comparing nitrous oxide-oxygen mixture inhalation and lidocaïne-prilocaïne cream.

BACKGROUND: Mechanical debridement of fibrin and/or necrosis promotes healing of arterial and venous leg ulcers but is limited by pain associated with the procedure. OBJECTIVE: The main objective of this study was to compare the respective analgesic effect of nitrous oxide oxygen mixture (NOOM) inhalation and lidocaïne-prilocaïne cream (LPC) application during the mechanical repeated debridement of chronic arterial and venous leg ulcers. METHODS: In this randomized, multicentre, open-label study, pain was evaluated before and after each care and debridement session using a Visual Analog Scale (VAS) and a Verbal Rating Scale (VRS), in the context of usual debridement and wound care process. The Quality of debridement and tolerability of the treatments were also assessed. RESULTS: Forty-one patients were randomized: 20 received NOOM and 21 LPC. Pain assessed by VAS and VRS was more intense in the NOOM group than in the LPC group (5.29 vs. 3.68 and 2.87 vs. 1.71, P<0.001, for the two scales respectively). No differences were found concerning quality of debridement, safety or tolerability between the two groups. CONCLUSION: This pilot study demonstrates the superiority of the LPC over NOOM for pain control during the mechanical debridement of chronic leg ulcers.

Assay for acetyl-CoA:arylamine N-acetyltransferase by high-performance liquid chromatography applied to serotonin N-acetylation.

A specific assay to measure the activity of the enzyme acetyl-CoA:arylamine N-acetyltransferase (EC 2.3.1.5) from pigeon liver is described. The assay is based on the HPLC analysis of N-acetylserotonin formed by the enzymatic reaction. A reversed-phase column (Spherisorb 5-microns ODS 2; 150 x 3.2 mm) eluted with 0.1 M sodium acetate (pH 4.75)/methanol (75:25) permits baseline separation of serotonin and N-acetylserotonin within 5.3 min. Several variables on the enzyme reaction were studied to obtain maximum activity. The enzyme is most active in glycine buffer at pH 9.5. The apparent Km value for serotonin (at 0.6 mM CoASAc) is 0.246 mM and 9.9 microM for CoASAc (at 1.5 mM serotonin). To avoid acetyl-CoA or N-acetylserotonin consumption in side-reactions, the enzyme was purified. A two-step purification process (ammonium sulfate fractionation and affinity chromatography on immobilised amethopterin) yielded 60-70% of the initial enzyme activity with a purification factor of 455-560.

Immobilization of acetylcoenzyme A synthetase and the preparation of an enzyme reactor for the synthesis of [11C]acetylcoenzyme A.

The enzyme acetylcoenzyme A synthetase (acetate-CoA ligase (AMP forming), EC 6.2.1.1) from Saccharomyces cerevisiae (baker's yeast) is used for the synthesis of 1 mumol [11C]acetylcoenzyme A. (CoA-[11C]Ac). A screening of the immobilization of the enzyme on differently derivatized controlled pore glass beads (50 nm pore size and 125-180 micron particle size) was performed. Several silanes, spacer arms and terminal reactive groups were tested. The immobilized enzyme was subjected to storage stability tests. From these experiments, the method of choice was selected: immobilization on CNBr-activated controlled pore glass. The immobilized parameters were optimized further to improve the activity of the enzyme-loaded glass beads. The latter were packed in a glass column. The kinetic properties of the column were investigated and optimized to obtain an almost complete conversion of 1 mumol acetate into acetylcoenzyme A (CoA-Ac) within a few minutes. This is realized with an enzyme reactor (13.0 x 0.5 cm) containing 6.12 U active acetylcoenzyme A synthetase immobilized onto 1 g controlled pore glass.

Prolactin cell subpopulations separated on discontinuous Percoll gradient: an immunocytochemical, biochemical, and physiological characterization.

A single-step procedure was devised to separate PRL cells from the rat anterior pituitary gland. After dissociation, cells were centrifuged on a Percoll gradient. Three layers were recovered. The composition of the different layers was evaluated using immunocytochemistry (with antisera to the six pituitary hormones), and in situ hybridization [with DNA complementary to PRL or to GH messenger RNA (mRNA)]. Both methods yielded identical values. PRL cells were recovered in the lower density layer (layer 1) with a good yield (that is 81% of the total PRL cells of the initial cell suspension) and in addition, markedly enriched (indeed 85% of the cells in layer 1 stained for PRL). A second layer (layer 2: intermediate density) contained most of the remaining PRL cells which were, however, heavily contaminated mainly by GH cells and cells that did not stain for any of the known pituitary hormones. A third layer (layer 3: higher density) was enriched in GH cells to 93% (representing, however, only 10% of the initial pituitary GH cells). In addition, PRL and GH were measured by RIA in culture medium and in cell lysates. Hormone biosynthesis was monitored by polyacrylamide gel electrophoresis and autoradiography after culture in the presence of [35S]methionine. These experiments confirmed that layer 1 was enriched in cells containing, and producing, PRL and depleted from GH cells. Cells in layer 2 contained and produced more GH than PRL. PRL cells from layer 1 responded to dopamine and to vasoactive intestinal polypeptide in the same way as PRL cells in the unseparated pituitary cell population. In contrast PRL cells in layer 2 had a lower basal secretion rate but a higher response to vasoactive intestinal polypeptide. Unless this represents a paracrine effect of non-PRL cells, PRL cells in layer 2 exhibit different properties and may therefore form a distinct subpopulation of PRL cells.

Transcriptional pattern of 21-hydroxylase gene (P-450C21) during embryonic development, before, and after birth in mice as determined by in situ hybridization.

21-Hydroxylase is a member of the P-450 superfamily of genes involved in the biosynthesis of cortisol and aldosterone in the adrenal cortex. Congenital adrenal hyperplasia, a well-characterized disease, originates from a lack of this enzyme. We present in this report an in situ hybridization study aimed at detecting 21-hydroxylase activity during murine development, from mid gestation to adulthood. Our results demonstrate that even during the embryonic period the adrenal cortex is the only major site of transcription of this enzyme, which is detectable beginning at embryonic day 14. In addition, a peculiar topographical pattern of transcriptional activity, characteristic of the stage of differentiation of the gland, could be drawn. Using a computer-assisted method, we were able to quantitate the relative transcription level at each stage of development. A steady increase in the level of transcription was demonstrated throughout embryonic life to birth, with a drop during the prepubertal period and a final rise at adult age. The possible physiological significance of our findings is discussed.

Microscale synthesis of nitrogen-13-labeled cisplatin.

A microscale synthesis of [13N]cisplatin (cis-dichlorodiammineplatinum(II), cis-DDP) from cyclotron-produced [13N]ammonia is presented. Temperature, reaction time, ratios, and concentration of reactants have been optimized for each step of the synthesis. Purification is performed by ion exchange chromatography. Radiochemical purity and optimization processes are controlled by high performance liquid chromatography and high performance thin layer chromatography--22 mCi [13N]cisplatin in 10 ml of solution is produced. The entire procedure takes approximately 15 min and the specific activity is approximately 300 mCi/mumole at EOB.

Cerebrospinal fluid flow waveforms: MR analysis in chronic adult hydrocephalus.

UNLABELLED: Henry-Feugeas MC, Idy-Peretti I, Baledent O, et al. Cerebrospinal fluid flow waveforms: MR analysis in chronic adult hydrocephalus. Invest Radiol 2001;36:146-154. RATIONALE AND OBJECTIVES: To analyze changes in cerebrospinal fluid (CSF) hydrodynamics in chronic adult hydrocephalus. METHODS: Phase-contrast cine-MR acquisitions were used to explore the ventricular system and the upper ventral cervical spaces of 16 patients. The aqueductal jet was explored in 32 control subjects. RESULTS: The duration of pulsatile caudal CSF flow (ie, CSF systole) was abnormally short in patients with active idiopathic and obstructive hydrocephalus. The duration of CSF cervical systole was normal in patients with stable hydrocephalus. The aqueductal stroke volume could be increased in stable communicating hydrocephalus. Patients who responded to shunting had shortened CSF systoles and hyperpulsatile ventricular patterns. Successful CSF diversion resulted in longer CSF systoles and CSF ventricular patterns that were no longer hyperpulsatile. CONCLUSIONS: Magnetic resonance analysis of CSF flow can show craniospinal dissociation and limitation of CSF outflow from the ventricles in both obstructive and communicating hydrocephalus; it should help determine the response to shunting in communicating hydrocephalus.

Autoradiographic localization of D1 and D2 dopamine receptors in the human brain.

The distribution of dopamine D1 and D2 receptors in several human brain regions was investigated using autoradiography with the radioligands [3H]SCH 23390 and [3H]spiroperidol. The highest densities of both dopamine receptor types are seen in the nucleus caudatus, putamen and nucleus accumbens. Whereas the density of the D2 receptors is similar in the two segments of the globus pallidus, the pars medialis of the globus pallidus contains a three-fold higher concentration of D1 receptors than the pars lateralis. D1 and D2 receptors are present in the amygdala and substantia nigra. Both receptor types are absent in the cerebellum. The thalamus contains low densities of D1 receptors but no D2 receptors. Only D2 receptors are seen in the anterior lobe of the pituitary gland. The whole cerebral cortex is rich in D1 receptors, while D2 receptors, in low concentrations, are confined to the entorhinal area and cingulate cortex.

Evaluation of a rapid, sensitive and specific assay for the determination of collagenolytic activity in biological samples.

Several methods for the determination of collagenolytic activity were compared from the point of view of sensitivity, selectivity, simplicity and practical value for large numbers of biological samples. A labelled collagen substrate was prepared using [3H]acetic anhydride. The specificity of the assay as well as conditions allowing an optimum detection limit were investigated. The influence of low temperatures, lyophilisation and salt concentration on Clostridium histolyticum collagenase have been investigated.

Plasma vitamin A in haemodialysis patients.

Different high performance liquid chromatographic systems were applied to the investigation of vitamin A metabolism in subjects undergoing haemodialysis. Plasma levels of retinol, retinyl esters and retinoic acid were measured. There was a significant elevation of plasma retinol and dialysis failed to normalise this level. No correlation with plasma concentrations of creatinine or urea was found. No differences in retinyl ester and retinoic acid levels were observed between healthy subjects and haemodialysis patients. These results suggest that retinol accumulation is not caused by a deficiency in its oxidative metabolism.

Identification and quantitative GLC determination of iproniazid in human urine.

A GLC method for the specific identification and quantitation of iproiazid, a potent monamine oxidase inhibitor drug, is described. The free drug isolated from urine samples by two-phase extraction reinforced with salting out. Identification and quantitative determination at the microgram level are done on aliquots of the chloroform extract by GLC, using the 2-butyl analog as an internal standard. Iproniazid and potentially interfering compounds present in the extracts are also identified by GLC-mass spectrometry and TLC for supporting evidence of the GLC method's specificity.

The decomposition of hypobromite solutions.

The stability of 10(-1)-10(-3)N hypobromite solutions, stored in brown or colourless bottles at room temperature, has been investigated. A reaction mechanism of decomposition has been proposed and some practical conclusions have been drawn concerning the optimal method of preparation and the required frequency of control of hypobromite solutions used as an analytical reagent.

Improved column systems for gas-liquid chromatography of iproniazid and iproclozide.

As a result of a comparative study performed on thirteen liquid phases an improved set of four analytically packed columns, i.e., Versamid-900, Versamid-930, XE-60, and OV-225 is withheld for successful gas chromatography of iproniazid and iproclozide. Retention data in terms of adjusted retention times and relative retentions, using structurally related compounds as reference, are reported. An evaluation of gas chromatographic performance of proposed columns is described.

Quantitative gas-liquid chromatography of iproniazid and iproclozide.

Analytically packed columns prepared with Versamid-930, Versamid-900, XE-60, and OV-225 as stationary phases were examined for quantitative gas-liquid chromatography of the potent monamine oxydase inhibitor (MAOI) drugs iproniazid and iproclozide. With the aid of chemically related substances as internal standards, response ratios were determined and linearities calculated by regression analysis. Using the 2-butyl analogs of compounds all four column systems permit quantitation of iproniazid and iproclozide with a percent standard deviation sigmaK of about 1% or less.

Diplopia as an initial manifestation of disseminated non-hodgkin's lymphoma.

A 37-year-old male presented a sudden diplopia. Ocular examination showed a partial paresis of the left eye (LE) on the left gaze, progressing in a few days towards a total ophthalmoplegia. Further investigation revealed an intra-orbital mass, immunohistologically diagnosed as a Diffuse Large B-cell Lymphoma (DLBCL), according to the WHO classification. Since the patient was in an advanced, disseminated stage of the disease (IVA-E), treatment was based on systemic and intrathecal chemotherapy with a pancranial radiotherapy. The clinical course was poor with only a 10-month survival. We wish to stress that the possibility of orbital malignancy in young adults with acute onset of ophthalmoplegia should be included in the differential diagnosis.