A proteomic approach to investigate potential biomarkers directed against membrane-associated breast cancer proteins.

The identification of specific protein markers for breast cancer would provide the basis for early diagnosis. Particularly, membrane and membrane-associated proteins are rich in targets for antibodies that may constitute suitable biomarkers of carcinogenesis. However, membrane proteins separation using 2-DE remains difficult.

Identification of isoenzymes using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

The identification of isoforms is one of the great challenges in proteomics due to the large number of identical amino acids preventing their separations by two-dimensional electrophoresis. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) has become a rapid and sensitive tool in proteomics, notably with the new instrumental improvements. In this study, we used several acquisition modes of MALDI-TOFMS to identify isoforms of porcine glutathiones S-transferase.

Matrix-assisted laser desorption/ionisation mass spectrometry for the direct analysis of enzymatically digested kappa- iota- and hybrid iota/nu-carrageenans.

Enzymatically digested oligosaccharides of kappa-, iota- and hybrid iota/nu-carrageenans were analysed using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry in the negative-ion mode. nor-Harmane was used as matrix. Depending on the stock concentration and the laser intensity applied, the oligosaccharides exhibited losses of sulphate units (neutralised by the Na+ ion, and thus non-stable), leaving the primary backbone structure in most cases with only the deprotonated sulphate groups (carrying the negative charge, stable).

Proteomic Analysis of Membrane-associated Proteins from the Breast Cancer Cell Line MCF7.

Background: Proteins associated with cancer cell membranes represent targets of choice for humoral immune response as well as potential tumour marker proteins in human malignancies. However, proteomic analysis of these proteins, and more generally of low-soluble proteins, remains difficult.

Materials And Methods: The breast cancer cell line MCF7 was selected to evaluate a sequential extraction method that enables simple fractionation of human cell proteins according to their subcellular localization, yielding subproteomes enriched in cytosolic and membrane-associated proteins, respectively.

Selective effects of partial striatal 6-OHDA lesions on information processing in the rat.

The present study was aimed at characterizing the cognitive deficits caused by the degeneration of nigrostriatal dopamine (DA) pathways by using the additive factor logic [Sternberg, S. (1969) Acta Psychol., 30, 276-315], a powerful reaction time (RT) method developed in humans and recently introduced in the rat [Courtiere, A.

Nitrous oxide impairs selective stages of working memory in rats.

Working memory impairment under narcosis has never been investigated. Furthermore, mechanisms by which narcosis disturbs working memory processes remain relatively unknown. The present work was aimed at answering to these two questions using a well-known normobaric narcotic gas, nitrous oxide (N2O), and a classical working memory task (a two-trial recognition memory task).

Selective effects of low-dose dopamine D1 and D2 receptor antagonists on rat information processing.

It is well established that the dopaminergic system influences simple reaction time (RT) performance. However, the role of this system in more complex information processing remains to be clarified. The present study was aimed at addressing this issue.

An additive factor analysis of the effect of sub-anaesthetic doses of nitrous oxide on information processing: evidence for an impairment of the motor adjustment stage.

Rationale: Nitrous oxide (N(2)O) inhalation, at subanaesthetic concentrations, impairs choice reaction time (RT). However, the functional locus of this effect remains to be ascertained. In the present study, this issue was investigated by applying the additive factor logic to the RTs of rats performing a visuo-motor task.

The additive factor method in rat information processing.

Sternberg introduced the additive factor method as a tool for discovering and studying in choice reaction time situations in human subjects. Underlying the method is the notion that if information processing consists of successive stages, then different factors affecting different stages must have additive effects on reaction-time measurements. The additive factor method has been extensively used in humans but few attempts have been made to examine whether or not additive reaction time patterns were obtainable in rats.

Behavioural effects induced by nitrous oxide in rats performing a vigilance task.

Nitrous oxide (N2O) effects were evaluated, as a behavioural model of inert gas narcosis, in rats performing a vigilance task in which they were required to respond to a slight luminous increment of the house-light. A dose-related decrease of correct responses was produced by the tested range of concentrations of N2O (from 30 to 70% N2O), with a parallel increase of anticipatory responses up to 60% N2O and a dramatic increase of omissions at 70% N2O. The influence of preparatory period duration on hits delays suggested a 'conditional probability effect' conserved under N2O.

Evidence for the involvement of the rat prefrontal cortex in sustained attention.

Previous studies suggest that, in both humans and rats, the prefrontal cortex (PFC) is involved in both selective and divided attention. We have also shown that the PFC is involved in response selection and that its involvement is modulated by the cognitive effort required by the task. However, the role of the PFC is much less clear when no response selection is required.

[Influence of partial and total castration on the growth and feed conversion performances of Poulfouli rams of the Far North Cameroon].

The authors compared the growth and feed conversion performances of groups of Burdizzo rams, castrated rams at an age of 6.5 months and partially castrated rams at 2 months by the short scrotum technique. After a 384-day experiment, the average weights are, respectively, 49.

[Tropical sprue. Apropos of a case observed in the Paris region].

A case of tropical sprue in a 73-year old parisian male returning from endemic areas is reported. Clinical manifestations were megaloblastic anemia, malabsorption and protein-losing enteropathy. Biopsy of the jejunal mucosa showed partial villous atrophy with thickening of the basement membrane region; fat droplets were observed inside and close to the epithelial cells on electron microscopy study.

[Primary hepatic carcinoma disclosed by Budd-Chiari syndrome. Apropos of a case. Review of the literature].

Hepatic carcinoma revealed by Budd Chiari syndrome in an eighty-four-year-old female patient is reported. With reference to this observation and to the twenty-two other cases previously reported in the medical literature, the specific pathological and clinical features of Budd Chiari syndrome caused by primary carcinoma of the liver are reviewed. Histological features of the liver tumour are discussed.

[Inverted polypoid hamartoma of the rectum in a child].

Hamartomatos inverted polyps of the rectum were observed in a 12 years-old boy suffering from recurrent rectal discharges of mucus. Diagnosis was made on examination of rectal specimens obtained by local excisions and finally by recto-sigmoïdectomy, showing ectopic lobulated glandular structures deep to the muscularis mucosae. This histological aspect must be differentiated from adenocarcinoma, but in the paediatric age, prognosis depends on the degree of diffusion of the hamartomatous tissue, which may lead to extensive surgery such as recto-sigmoïdectomy.