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M Bellone

Publications and source records attributed to M Bellone.

47 records · Page 3Linked to original sources

The main immunogenic region of the nicotinic acetylcholine receptor. Identification of amino acid residues interacting with different antibodies.

In myasthenia gravis a highly conserved area of the nicotinic receptor (AcChR) dominates the autoantibody response (main immunogenic region, MIR), and it is formed by residues within the sequence segment 67-76 of the AcChR alpha-subunit. We have studied the binding of eight anti-MIR mAb to synthetic peptides containing the sequence segment 67-76 of the human alpha-subunit, and peptide analogues containing single residue substitutions of this sequence. We used also a peptide where both Asp70 and Asp71 were substituted by glycine residues. The binding of six anti-MIR mAb was strongly influenced by several substitutions. All these mAb required residues Asn68, and Pro69 for binding. Five of them required also Asp71 and Tyr72. Substitution of Asp70, which is an Ala residue in Torpedo AcChR, was irrelevant for the binding of an anti-Torpedo and an anti-Electrophorus mAb, and moderately reduced the binding of an anti-human mAb (no. 203). Substitution of Trp67 moderately reduced the binding of some of these mAbs. A mAb of this group (the antihuman mAb no. 198) bound in a manner only slightly influenced by ionic strength, whereas the binding of the other five mAb of this group was very sensitive to the ionic strength. Two anti-Electrophorus MIR mAb bound similarly to all peptide analogues in low ionic strength. At high ionic strength only the peptide analogue where Asp 70 was changed to a Gly residue bound significantly. This may indicate that the Electrophorus MIR has an uncharged residue at this position, as does Torpedo AcChR. Residues at position 73, 74, 75, and 76 were of little or no importance for the binding of all anti-MIR mAb. A free amino terminus was essential for the binding of most mAb. The results of competition experiments between different peptides and native AcChR for mAb binding were consistent with those obtained in direct binding experiments.

Acetylation↗

Thymopentine treatment improves clinical and immunological functions in aged subjects with chronic bronchitis.

The effect of in vivo thymopentine treatment (50 mg/subcutaneously every other day for six weeks) on clinical features and in vitro immunological parameters was evaluated in ten aged patients with chronic bronchitis. In vitro immunological studies were performed before and after treatment both on phenotypic (OK monoclonal defined lymphocyte subpopulations) and functional parameters (blastogenic responses to polyclonal mitogens Concanavalin-A and Phytoemagglutinine). Thymopentine did not significantly affect lymphocyte subpopulations, which were reduced before pharmacological treatment, when compared to those of young healthy controls. Peripheral blood lymphocytes blastogenic response to polyclonal mitogens was restored, even though proliferation did not reach the values of young healthy subjects. Thymopentine treatment significantly improved lymphocyte functions, without being able, however, to overcome completely the age-dependent loss of blastogenic responses. Nevertheless the favourable evolution of clinical symptoms we observed in our study may be, at least in part, related to the improvement in vivo of those immunological functions that we studied in vitro. Eight out of ten patients showed an evident improvement of symptoms and signs of chronic bronchitis after thymopentine treatment and four of them arrived to a complete remission from infectious episodes. No side effects were noted. Although still preliminary, these results seem to be encouraging as thymopentine could be used with success as an immunomodulating agent in aged people.

Adjuvants, Immunologic↗

Methisoprinol effect on enriched B and T lymphocyte populations stimulated with phytohemagglutinin.

The Authors investigated the effect of methisoprinol (Inosiplex) on separated B and T lymphocytes from 8 healthy donors. B or T treated cells, recombined with T or B untreated cells, were subsequently mitogen stimulated. Proliferative response resulted significantly increased, in comparison to a control, when T lymphocytes were preincubated with the drug, while treating only B lymphocytes led to a decrement. These data confirm the hypothesis of a direct action of the drug on T lymphocytes, but are also consistent with its influence on B cells too, even though with an opposite effect.

Adult↗

Methisoprinol effect on enriched B and T lymphocyte populations stimulated with phytohemagglutinin.

The Authors investigated the effect of methisoprinol on separated B and T lymphocytes from 8 healthy donors. B or T treated cells, recombined with T or B untreated cells, were subsequently mitogen stimulated. Proliferative response resulted significantly increased, in comparison to a control, when T lymphocytes were preincubated with the drug, while treating only B lymphocytes led to a decrement. These data confirm the hypothesis of a direct action of the drug on T lymphocytes, but are also consistent with its influence on B cells too, even though with an opposite effect.

Adult↗

Impairment of lymphocyte suppressive system in recent onset insulin-dependent diabetes mellitus. Correlation with blood glucose and serum insulin levels.

In a previous study, we observed an impairment of the theophylline-induced suppressive system in recent onset IDDM patients, and demonstrated also a correlation with metabolic derangement. The aim of this study was to better investigate the relationship between theophylline sensitivity (ThS) and blood glucose/plasma insulin levels in recent onset IDDM patients subjected to preprogrammed variations by an insulin/glucose clamp with artificial pancreas. Eight patients were studied within 8 weeks from the onset of IDDM. ThS was evaluated as the ability of theophylline to inhibit blastogenic response of peripheral blood lymphocytes (PBL) to Concanavalin A (ConA), after 120 min preincubation of the cells. All patients were connected to an artificial pancreas. Through i.v. continuous insulin infusion (0.02 U/kg/h) and/or i.v. continuous glucose and saline infusion, the following experimental conditions, lasting at least 1h, were obtained: T1: relative euglycemia and normal insulinemia; T2: relative euglycemia and hyperinsulinemia; T3: hyperglycemia and normal insulinemia; T4: hyperglycemia and hyperinsulinemia. ThS was maintained in 6/8 patients at T1 and in 8/8 patients at T4. ThS was lost in 4/8 patients at T2 and T3. These data suggest that the loss of ThS induced by hyperglycemia can be corrected by hyperinsulinemia, and that it is maintained when euglycemia is accompanied by hypoinsulinemia. It is lost when these two parameters lose their interrelationship.

Activity Cycles↗

[Study on psychiatric disorders and defensive process assessed by the "defense style questionnaire" in sterile males SAMPLE consulting in andrology].

BACKGROUND: The literature about artificial insemination and the associated psychological, psychiatric and sexual disorders is relatively rich. But the majority of these studies is made in gynaecology, with a feminine approach of the disorder. There are very few works led in andrology. This justified the investigation of new trails in order to understand better the clinical context of the sterile man. We undertake a study about the psychiatric disorders among sterile men and about the defense styles. These are a clinical entity recently introduced in the quantitative psychopathology research. The defense style questionnaire (DSQ) is a psychometric scale used in common practice in order to measure the defense styles. OBJECTIVES: We made this study in order to examine the psychiatric state of a sterile males sample consulting in andrology; to assess the defense style by means of the Bond and al DSQ-88 ; to look into a difference between the defensive process according to their clinical situation of azoospermic males or as the oligoazoospermic males and finally, to reveal a correlation between the psychiatric disorders developed in this sample of sterile males and the defensive process they used. METHOD: There were 42 people (22 azoospermic males and 20 oligoazoospermic males) aged between 23 and 49 years old in the analysed sample. These have been selected at the surgery of andrology at the RUHC of Lille, depending on their arrival order for 6 months. There was no significant difference between the two groups as far as the age and the education standard are concerned. The selection criteria were medical and somatic. Our sample population were divided into two groups: azoospermia (no spermatozoon found in the semen analysis) and oligoasthenospermia (decrease of the number and the mobility of the spermatozoa and an increase of the percentage of atypical forms). The method first consisted in the DSQ, followed by the analysis of the psychiatric state according to the DSM IV, a hetero questionnaire to collect some general information about infertility and a self questionnaire about the sexual, conjugal and social effects of infertility. The DSQ and the interviews took place in the andrology department with the same investigator trained for this job. RESULTS: We found in our sample 26.2% of psychiatric disorders according to the DSM IV with a significant over-representation of generalized anxious disorder and somatization disorder. The comparison between azoospermic males and oligoazoospermic males patients showed the absence of significative difference as far as psychiatric morbidity rate and the use of defense styles are concerned. DISCUSSION: Our sample defended himself in accordance with modalities similar to the general population and used defense mechanisms preferentially belonging to the mature defense style, such as humor, repression and anticipation. The psychiatric pathology was significantly correlated to the preferential use of withdrawal, consumption, reaction formation and lack of humor use. We also confirm in our study the fact that the subjects using especially neurotic defense styles are more likely to develop a psychiatric disorder than the others. Our male sample is a waiting population and threatened by failure. The situation of wait creates anxiety. We also know that infertility is one of the most stressful situations a couple might face. However, our study did not enable us to know the precise relations between generalized anxious disorder and infertility, especially whether the generalized anxious disorder preceded this pathology or not. The over-representation of a somatization disorder only allows us to acknowledge its existence. We can also deduce from that a possible link between infertility and psychic disorder, even if no research permitted to affirm to date the existence of interrelations linking infertility and psychic life. On the whole, this population was suffering despite 73.8% of the patients had no confirmed psychiatric disorder. It is the reason why a liaison psychiatry more inserted into highly specialized teams is interesting, especially because it includes a medical and psychological approach of such disorders. The defense mechanisms preferentially used by this population were humor, repression and anticipation. Humor can only be considered as a defense mechanism when it is applied to oneself. The population who has no psychiatric disorder more uses humor. Does humor protect against the development of a psychiatric pathology, as certain authors proved it ? On the other hand, is repression really protective? It didn't interfere in our study about the development of a psychiatric pathology. So we can suppose that repression was protective for our whole sample, but we can not prove it. However, we wonder if this mechanism works after the failure of an artificial insemination is announced. In which measure such a stress can be repressed out of the conscience field? As for anticipation, it is used by our population who is for the most part in good health. But the question is to know if our sample really envisaged all the different possible solutions or only the success of artificial insemination. As some other works, we confirm that the, psychiatric, people significantly use the neurotic style. Our psychiatric patients used less humor and more consumption, withdrawal and reaction formation than the sane people. Consumption is rarely considered as a defense mechanism by some other authors. And yet, consumption and the existence of psychiatric disorders were very closely linked. This association is found again with anxiety in other studies. The correlation between psychiatric disorder and withdrawal was veryimportant too. The DSM lV defines withdrawal as an apathetic withdrawal. It is not an apathetic withdrawal in our population because the average scores for the ,, activity >, defense mechanism remained high. In our sample, the use of this defense mechanism would encourage the expression of psychiatric troubles. The reaction formation quoted by Freud and Bergeret are both valorised in our society. What kinds of reaction formations use these men ? Are they pathological ? Our study can not answer to these questions. However, the DSQ items examining the reaction formation present its "socially promoted" aspect and forget the pathological one. It has been showed that the evaluation of the defense modalities in a certain type of population can allow the emergence of specific defense mechanisms. This can be considered as predictive factors of development of a mental pathology. The evaluation of specific mental defenses could permit to define vulnerability and affinity for given affections instead of simple personality traits or profiles. Most part of the works shows results in favour of the capacity of DSQ to assess the different defense mechanisms according to the diagnosis groups. But the insufficient numbers of studies moderate on the whole the hypothesis of the existence of specific defense mechanisms--protective factors and factors of vulnerability--linked to a given psychiatric disorder. CONCLUSION: There is not a difference of psychological effect in terms of degree of sterility. On the other hand, the existence of over-represented psychiatric disorders with sterile males compared with a control group force Consultation-Liaison psychiatrists and andrologists would be able to understand the pain beyond the need of acting by the artificial insemination. In our opinion, this justifies the fact that the patients should have the opportunity of expressing, in the department where they are treated, all the feelings inherent to their personal and conjugal drama as part of a specialized treatment. Our study confirms the difficulty to know whether some defense mechanisms are vulnerability factors for a certain psychiatric disorder or whether the defense mechanisms are an epiphenomenon of a particular psychiatric disorder. This is the reason why a lot of authors having worked with DSQ agree to conclude that additional prospective studies, which would permit to make a link between the defense mechanisms anda certain psychiatric pathology, are necessary. In the case we study, it is important to explore the defensive modalities before the infertility diagnosis and after the birth of a child, with a more important sample population. A better knowledge of the defensive modalities of such a population, used in a psychotherapeutic context could help to prevent the appearance of psychiatric disorders or, if not, to anticipate them.

Adaptation, Psychological↗

Takayasu's arteritis: therapeutic strategies.

Takayasu's arteritis (TA) is a chronic inflammatory disease of unknown origin, primarily affecting the walls of large vessels. TA can be a severe and life-threatening disease, and has relevant consequences for the patient's life-style. Mortality and morbidity depend on both the direct effect of the vascular lesions and the following complications. The mainstay of TA therapy is based on the use of glucocorticoids alone or in association with cytotoxic drugs. Unfortunately, in the majority of cases, only a partial control of the disease is obtained. The therapeutic strategy may vary in different countries, and in Japan, where the disease was first described, high dose glucocorticoids are preferred to glucocorticoids in association with cytotoxic agents. We present here a review of the pharmacologic strategies most commonly adopted for the treatment of TA in America, Italy and Japan, together with our experience on 31 TA patients, who have been followed in the last two decades. The discussion is also open on which criteria are more accurate in measuring disease activity.

Female↗