[Validation of antibody screening by indirect antigloblin test and ABO blood typing by filtration and microplate techniques: assessment of robustness]. / Maîtrise des tolérances métrologiques : application à la recherche des anticorps anti-érythrocytaires (RAI) en test indirect à l'antiglobuline (TIA) et au groupage sanguin ABO par les procédés de filtration et en microplaque.

According to requirements of the French Committee for Accreditation (Cofrac), it is essential to use validated and standardised methods in Immunohematology. This imposes first the knowledge of metrological tolerances for all the technics. Two multicenter studies were carried out to define the maximal acceptable deviations concerning incubation temperature and time, volumes of patient plasma and tests cells for antibody screening using indirect antiglobulin test on one hand and for reverse grouping on another hand. All equipment used (temperature test chamber, chronometer, pipettes) were calibrated according to Cofrac standards. The antibody screenings were performed manually using 3 different filtration systems: ID Diamed, Biovue Ortho and Scangel Biorad, the same tests cells, a standard 20 ng/mL anti RH1, a positive control anti KEL1 and a negative control; the reverse blood grouping was performed manually using the above mentionned filtration systems and microplate technic with the same A1 and B test cells. These two studies showed that all the tests from the multiples combinations of the above parameters gave the same results and allowed us to define a range of tolerance for 4 critical physical parameters involved in the antibody screening and blood typing.

[Automation of the immunohematology laboratory]. / Automatisation au laboratoire d'immunohématologie érythrocytaire.

Automation finds a particularly justified application in the field of immunohematology in which any human failure can have dramatic consequences for the patients. The purposes of automation, indissociable from computerization, were reminded by the French regulatory: to decrease the risks of human error linked to each step of the tests performed; to guarantee a reliable traceability of all the elements having contributed to the test process; to manage all the alarms of dysfunction of the system. The main devices available today permit automation of a part of the pre-analytical phase and of all the steps of the analytical phase by the realization in routine of ABO-RH1 grouping, phenotyping, of irregular antibody screening and of compatibility testing. They use the reaction of agglutination either in micro-plates or in filtration. One distinguishes two types of materials: full automates managing all the steps from the sample positioning on the carrier down to the final result without any handling of the samples (Autovue, Galileo, ID gel station, Qwalys, Tango, Techno) and the semi-automates, which require intervention of an operator for the phases of centrifugation, stirring and incubation (Mitis 2, Hemos, Rosys, Swing) the reading being automated for all. All include the possibility of a connection to the central data processing system . If some devices allow the choice of reagents, others can only work with the reagents supplied by the manufacturer. In all the cases, optimization of the automated systems implies a specific training of the staff and the strict compliance with the standard operating procedures by each individual.

[Suitability of intraoperative autotransfusion]. / Suivi des techniques de récupération de sang en peropératoire.

This work presents the procedure applied by our hospital to assess the quality and security of intra operative autotransfusion. The suitability of the three following variables has to be constantly assessed: performance of the machines to concentrate and wash collected blood, bacterial contamination of processed blood and rate of adverse events. We note that the procedure is applied with participation of medical and nursing staff. Since its setting-up, we note an amelioration of suitable variables.

Combined analysis of islet cell antibodies that cross-react with mouse pancreas, antibodies to the M(r) 64,000 islet protein, and antibodies to glutamate decarboxylase in type I diabetic patients.

OBJECTIVE: A combined analysis of whether islet cell autoantibodies (ICAs) are cross-reactive with mouse pancreas, with glutamate decarboxylase (GAD) antibodies, and with 64K antibodies was performed in a large sample of recently diagnosed type I diabetic patients. The disappearance rates of these different autoantibodies were compared in some patients after onset of the disease. The aims were to determine patterns in GAD/64K antibodies with regard to cross-species reaction of ICA and to assess whether GAD could contribute to ICA positivity in mouse and human pancreases and whether the simultaneous search for all the antibody specificities enhances the detection of autoimmune stigma. RESEARCH DESIGN AND METHODS: ICA detected by immunofluorescence in human and mouse pancreases, antibodies immunoprecipitating the 64K rat islet antigen, and antibodies immunotrapping brain GAD activity were quantified at diagnosis of diabetes in 95 patients and in sequential samples during 1 year after diagnosis in 13 patients. The contribution of GAD to ICA positivity in mouse and human pancreases was evaluated by the analysis of correlations between tests and by the ability of brain homogenate to block ICA reactivity in pancreases from both species. RESULTS: ICAs were detected in human pancreases in sera from 63 (66%) patients, among which 61% bound also to a mouse pancreas. GAD and 64K antibodies were strongly correlated (P < 0.0001) and were detected in 69 and 73% of the patients, respectively. All but two patients with ICA in human pancreas also displayed either ICA in mouse pancreas or GAD/64K antibodies. Among 32 patients without ICA in human pancreas, 54% displayed either GAD/64K antibodies or ICA in mouse pancreas. Only 16% of the patients displayed neither ICA nor GAD/64K antibodies. A correlation (P < 0.005) was found between ICA in human and mouse pancreases. GAD or 64K antibodies were strongly correlated with ICA in human pancreas (P < 0.0001), but not with ICA in mouse pancreas. After preincubation of six sera with GAD-containing brain homogenate, ICA titers were unaffected in mouse pancreas but reduced in human pancreas. ICA titers in mouse pancreas were decreased after 3 months (P < 0.01) in diabetic patients, contrasting with the stability of ICA in human pancreas and GAD antibodies by 1 year after diagnosis. CONCLUSIONS: According to cross-species reaction, we confirm the heterogeneity of ICA in a large series of type I diabetic patients, ICAs that cross-reacted with mouse pancreas being more frequent than ICAs without cross-species reactivity. GAD and 64K antibodies were also present in a majority of patients. The simultaneous search for all the antibody specificities enhances the detection of autoimmune stigma so that only a few patients did not display any autoantibody at diagnosis. GAD is not the target of ICAs in mouse pancreas, whereas GAD accounts for ICA positivity in human pancreas. The conclusion that ICAs in mouse pancreas are not GAD-reactive is reinforced by the fact that they are more transient after onset of diabetes than are GAD antibodies or the complex mixture of ICAs in human pancreas.

[Organization for the coverage of the transfusional needs of patients with hemoglobinopathy at the Établissement français du sang Bretagne]. / Organisation de la prise en charge des besoins transfusionnels des patients atteints d'hémoglobinopathie à l'Établissement français du sang Bretagne.

UNLABELLED: Brittany is a low prevalence region for hemoglobinopathies. Despite of that, the number of patients is increasing each year. In 2013, 140 patients were known at the EFS Bretagne, and medical consultations are growing for 50% each year since 2011. The consequence is an increase of needs of 22% of compatible packed red blood cells. To anticipate the announced progress, various actions were implemented as study groups, creation of a new informatic prescription for red blood cells phenotyping, promotion of donation, transfusion organisation. RESULTS: Fifthty-nine percent of the 400 ABO RH-KELL, FY, JK, MNS 3, 4, red blood cells were realised on the basis of this new informatic prescription, as the 99% of the packed red blood cells identified Fy (a- b-). So, 92% of the compatible transfused packed red blood cells were already in stock when the patients needed them. CONCLUSIONS: In Brittany, that organisation leads to assume qualitative and quantitative transfusion for sickle cell disease in more than 90% of cases, with fast distribution. In the same time promotion of donation is done to increase the diversity of donors.

Red blood cell polyamines, anaemia and tumour growth in the rat.

In rats with Mat Lylu prostatic carcinoma, significant changes in blood composition and red blood cell (RBC) characteristics were observed. Anaemia, characterised by a decrease in the number of RBC and the reduction of haemoglobin and the iron content in plasma, was correlated with tumour size and the accumulation of spermidine and spermine in the RBC. In large tumours, spermidine levels were increased by 8-fold over normal value. Spleen weight and splenic spermidine concentrations were enhanced in animals with tumours. After splenectomy, the rate of tumour growth decreased by 30%. It is proposed that anaemia in tumour-bearing animals is caused by enhanced RBC lysis, owing to the alteration of the rheological properties of RBC. These may be caused by the alterated surface characteristics due to polyamine accumulation. RBC lysis and high concentrations of polyamines in RBC and spleen appear, not only to favour tumour growth, but also to compromise the immunological defence mechanisms against neoplastic invasion.

Anti-pancreatic autoimmunity and Graves' disease: study of a cohort of 600 Caucasian patients.

The aim of this study was to investigate the frequencies of clinical diabetes and humoral markers of anti-pancreatic autoimmunity in a homogeneous population of 600 Caucasian patients with recently diagnosed Graves' disease (GD), in order to characterize the specific features of this group of endocrine patients among subjects at risk of diabetes. Ten were already diabetic at GD diagnosis. Among the 590 non-diabetic patients, 29 had islet cell antibodies (ICA), including 15 with low titre ICA and only 1 ICA-positive subject with a familial history of diabetes. Twenty-four patients had insulin autoantibodies, including three in association with ICA. Glutamic acid decarboxylase (GAD)/64 kDa antibodies were found in 16 of the 150 tested sera, including 13 of the 29 ICA-positive sera. Four ICA-positive patients displayed 37/40 kDa antibodies, including three in association with GAD/64 kDa antibodies. During follow-up, one of the ICA-positive patients developed insulin-dependent diabetes, 14 years after the GD diagnosis. To summarize, this anti-pancreatic autoimmunity study was focused on a large but specific and homogeneous group of subjects at risk for diabetes: recently diagnosed GD patients. This population was characterized by a high prevalence of GAD/64 kDa antibodies but also by a low frequency of evolution towards diabetes and the slowness of the process which could be due to the fact that only a minority of subjects possessed a sufficient combination of anti-pancreatic markers at the same time.

Combined analysis of long-term anti-beta-cell humoral reactivity in type 1 diabetes with and without thyroid disease.

The prevalence and levels of islet-cell antibodies (ICA) decrease in the years following diabetes onset but may persist, particularly in patients with concomitant autoimmune disease. The aim of this cross-sectional study was to investigate the frequencies, associations and levels of the major anti-beta-cell antibodies in long-standing diabetic patients (median duration: 14 years; range 5-47 years) with and without autoimmune thyroid disease (ATD) in order to consider the specific antipancreatic immunologic features associated with endocrine autoimmunity. Both ICA and glutamic acid decarboxylase (GAD) antibody (GAD-A) frequencies were increased in diabetic patients with ATD (38 vs 23%, p = 0.03 and 70 vs 21%, p < 10(-4) respectively). Although IA2-A frequency tended to be higher in diabetic patients with ATD, no significant difference was seen (37 vs 26%, p = 0.14). GAD median level was significantly higher in the diabetic group with ATD (15 vs 5 units, p < 10(-4)). IA2-A and ICA median levels were similar in both groups. Regardless of the combined analysis performed (ICA/GAD-A, ICA/IA2-A or GAD-A/IA2-A), the prevalence of combined antibody positivity was higher in diabetic patients with than without ATD. In both diabetic populations, ICA and GA-DA were significantly associated (p < 10(-4), and their levels were correlated (r = 0.42, p < 10(-4) and r = 0.584, p < 10(-4) respectively). No significant correlation was seen between IA2-A levels and either ICA or GAD-A titres. It is concluded that Type 1 diabetes mellitus with ATD is characterised by increased persistent humoral islet-related reactivity, particularly directed towards GAD.

Multiple antibody status in type 1 diabetic patients and subjects at various risk with islet-cell antibodies.

The frequency of 37/40 kD antibodies and their association with other pancreatic humoral markers were studied in 109 recently diagnosed Type 1 diabetic patients and 116 subjects with islet-cell antibodies (ICA) at various risk for this disease (64 relatives of Type 1 diabetic patients, 23 schoolchildren with no family history of diabetes, and 29 patients with Graves' disease). At the time of diagnosis, 37/40 kD antibodies were detected in 45% of Type 1a and 77% of Type 1b diabetic patients (p = 0.03). Antibodies to glutamic acid decarboxylase (GAD) and/or 37/40 kD were present with the same frequency as ICA (86%). The frequency of 37/40 kD antibodies was not significantly different between the 3 groups at risk, in contrast with GAD antibodies which were found at a lower frequency in schoolchildren (p < 0.02). Frequencies of other pancreatic markers (ICA cross-reactive with mouse pancreas and insulin autoantibodies) and the combination of ICA with at least two other markers were significantly higher in relatives than in the other groups at risk (p < 0.02). Out of 116 ICA-positive non-diabetic subjects, 10 developed diabetes. All 10 displayed 37/40kD and/or GAD antibodies during the prediabetic phase. In 8 of these 10 patients, ICA was combined with at least two other markers, whereas this association was detected in only 17 of the remaining 106 subjects who did not progress to diabetes (p < 10(-4). Thus, 37/40 kD antibodies were found in about half of Type 1 diabetic patients, and with a higher-frequency in Type 1b than 1a. In ICA-positive non-diabetic subjects, our date confirm that a combination of multiple antibodies, including GAD antibodies and 37/40 kD antibodies, can enhance the predictive value for diabetes. Comparison of ICA-positive relatives of diabetic patients, schoolchildren and patients with Graves' disease revealed distinct frequencies and combinations of markers of diabetes. This might reflect different patterns of progression among these 3 groups.

[Analytical validation in erythrocyte immunohematology]. / Validation analytique en immunohématologie érythrocytaire.

In a transfusional or foeto-maternal context, hemolysis by incompatibility due to anti-erythrocyte antibodies (regular or irregular) remains the most frequent and most serious immunological risk in the receiver. In order to prevent this risk, a number of actions must be taken, such as the realization of the immunohematologic analyses for which the methodological practices have been legislated because of their serious clinical consequences. Several elements play a role in the reliability of the analyses and their results: the selection of the reagents and their validation in the routine technique used; the validation of reception; the controls involved in secondary preparations (e.g., blood cells reagent); and the daily internal controls. All this requires the choice of adapted controls and the management of possible anomalies.

Section 1B: Rh flow cytometry. Coordinator's report. Rhesus index and antigen density: an analysis of the reproducibility of flow cytometric determination.

Fifty-seven IgG monoclonal anti-D antibodies were evaluated in the Rh flow cytometry section, in which 12 laboratories participated. Staining protocols and a fluorescein (FITC)-conjugated Fab fragment goat anti-human IgG (H + L) as a secondary antibody were recommended but not mandatory. A CcDEe red blood cell (RBC) sample that was shown to be homozygous for RHD by molecular methods was supplied and used as internal 'standard RBC' throughout all experiments. An RBC panel comprising two partial D and four weak D types was supplied as well. The use of standard RBC reduced the variability of the data among the laboratories and allowed the conversion of fluorescence data into epitope densities, which were compounded in an antigen density (antigen D per RBC). The highest antigen density was determined for DVI type III, followed by DVII and weak D type 3; the lowest antigen density were determined for weak D type 1 and type 2. Nine of the 12 participating laboratories discriminated three groups of aberrant RhD that had similar Rhesus indices (RI): D category VI with RI = 0; weak D type 2 and type 3 with an high RI; and D category VII and weak D type 1 with an intermediate RI. The antigen densities and the Rhesus indices obtained correlated well among the laboratories of this Workshop section despite different staining protocols, secondary antibodies and instrumentation.

Multicenter study of an erythro-aggregometer: quality control and standardization.

There is a need for quality assurance procedures in hemorheology, especially for clinical and pharmacological studies, which require reliable and well-calibrated instruments to be interpretable and comparable. Preliminary investigations allowed preparation of standardized SM (normal NS and hyperaggregable HS), and checking of storage conditions (in accordance with the guidelines of the SSC of ISTH) of RBC in nutritive SAG mannitol for at least 2 or 3 weeks with subsequent washings and resuspension in SM. In our study, we compared erythro-aggregometers of the same brand in 6 laboratories, using the same red blood cells (RBC) and suspending media (SM) for each series of tests. EA was measured by laser backscattering with determination of aggregation time (AT), partial dissociation threshold (PDT) and aggregation index (AI). Prior to the study, devices were set up on the same day with the same standardized blood, and calibration data were then analyzed. Within-assay precision (WAP) was assessed on 3 days for the 2 types of SM (n = 18 x 2). Between-assay precision (BAP) was assessed on 6 occasions, once every month (n = 6 x 2 x 6). Accuracy was studied with 3 series of RBC resuspended in 10 SM of "unknown" aggregability. Good agreement was observed between 5/6 centers for the 3 parameters of EA. WEP was good: CV of AT ranging from 1.4 to 2.5% for the NS and from 1.4 to 2.4% for the HS. In each center, BAP was slightly lower than WEP (CV: 8-11.8% for the NS and 3.8-4.7% for the HS over the 6-month study), with no drift, except for one center. Precision was always better with the HS than with the NS which seemed a better tool to assess it. As to accuracy, non-significant differences were generally found between centers, with similar data to the reference values. This work also stressed the importance of the RBC parameter itself in rheological data. For the first time, a protocol for standardization of EA has been developed and evaluated, permitting the Quality Control of this technique.

[Erythrocyte aggregation and vascular pathology]. / Agrégation erythrocytaire et pathologie vasculaire.

The aggregation of erythrocytes plays an essential part in vascular diseases involving both the veins and the arteries. In the veins, where the lowest blood flow rates are observed, the conditions of flow foster the aggregation of the erythrocytes, which accounts for blood hyperviscosity that may reinforce the effects of the stasis. In arterial diseases, hyperaggregation of the erythrocytes resulting from risk factors such as smoking, high BP, diabetes, disorders of lipemia, etc. contributes to the formation of stenosis, which has severe consequences for the patient. The prospects of the treatment aimed at correcting the hemorheological disorders caused by hyperaggregation of the platelets are ruled by Poiseuille's formula and based on hemodilution processes and the use of agents lowering fibrinogenemia or molecules improving the forming properties of the red blood cells.

[Exploration of the various steps of polymorphonuclear neutrophil function in diabetic patients]. / Exploration des différentes étapes du fonctionnement des polynucléaires neutrophiles chez les patients diabétiques.

UNLABELLED: Vascular complications in diabetic patients is a complex, probably multifactorial phenomena involving cellular phagocytosis. The aim of this study was to evaluate polymorphonuclear performance in 61 infection free diabetic patients based on tests of the different cell functions: 1) adhesion:adhesion molecule expression CD11a, CD11b, CD11c; adhesion test on nylon fibers. 2) chemotaxis:chemotaxis under aragose to FMLP (bacteria oligopeptide) and complement fractions. 3) Phagocytosis:latex beads. 4) Bacteriocidal power:chemoluminescence photometric oxidative potential before and after stimulation with opsonized zymosan and PMA; reduction of tetrazolium nitroblue. RESULTS were analyzed according to type of diabetes, glucose control, duration of the disease, history of infection and presence of vascular complications. RESULTS: compared with a group of 30 controls, the diabetic patients had a significant impaired polynuclear chemotaxis function (p < 0.001) with both spontaneous adhesion and increased expression of adhesion molecules (CD 11b, CD 11c). The chemoluminescence test was increased at the baseline level due to spontaneous polynuclear adhesion and increased production of free radicals. This response decreased after stimulation compared with controls. The type of diabetes, Hb A1c level and history of infection did not appear to have an effect. Inversely, changes in chemotaxis and chemoluminescence were greater in patients with vascular complications. In summary, all the functions of polynuclear neutrophils tested were altered in diabetic patients and could favor vascular complications and infections episodes.

[Rheologic and biophysical aspects of cellular adhesion and aggregation: importance in hemorheology]. / Aspects rhéologiques et biophysiques de l'adhésion et de l'agrégation cellulaire: importance en hémorhéologie.

Interactions between blood cells in the form of cellular aggregates or adhesion are observed in a variety of normal and pathological conditions. Aggregation of erythrocytes or platelets, adhesion of platelets and leucocytes and immune agglutination of RBC are examples of interactions involving blood cells. Cell adhesion and aggregation are modulated by specific interactions (antigen-antibodies reactions, adhesive macromolecules interactions...) or non-specific (van der Waals forces, electrostatic interactions, molecular bridgings...). These interactions may result in morphological and structural changes, or polarization phenomena. At the dynamic level, cellular adhesion (or aggregation) can divided in 4 main steps: transport, cellular activation (endogenous or exogenous), morphological, physical or steric rearrangements, contact (intercellular or on an artificial surfaces). It will be the nature of the interactions involved in these steps that will determine the binding cohesion and kinetic. In this paper, different types of interactions and the regulation mechanisms of adhesion and aggregation phenomena involved in blood hemodynamics will be summarized and some examples (RBC or platelets aggregation; platelets or leucocytes adhesion) will illustrate the importance of these phenomena in clinical hemorheology.

[Improvement of hemorheologic parameters in hemodialyzed patients treated with human recombinant erythropoietin]. / Amélioration des paramètres hémorhéologiques chez les patients hémodialysés traités par érythropoiétine humaine recombinante.

Recombinant human erythropoietin (rhu EPO) is the choice treatment of dialytic anemia; however, this therapy has side effects due to the increased number of blood components involved. It seemed to us worth assessing, by hemorheological study, the impact of such a treatment on blood flow properties, already impaired in this type of patients. This study was designed to measure the evolution of hemorheological parameters in 16 hemodialysed patients before and after 2.3 and 6 months of treatment with rhu EPO. Hemorheological work-ups included: erythrocyte filtration with a hemorheometer; blood and plasma viscosities (LS30), ATP and 2.3 DPG, RBC aggregation (Sefam erythroaggregameter), RBC morphology under a scanning electron microscope; blood counts and full biochemical work-ups were performed to explore renal function. The results showed, besides a significant increase in hemoglobin: normalized rigidity index, reflecting the better deformability of erythrocytes; a moderate increase in blood viscosity with uncorrected hematocrit, becoming significant after 6 months of treatment. This increase however did not reach the values that could be expected with the increased hematocrit (it was probably balanced by improved erythrocyte deformability, which is confirmed by the fact that with corrected hematocrit, blood viscosity decreases during treatment). Studying erythrocyte aggregation in hemodialysed patients reveals, in the absence of any treatment, a decrease in aggregation time and a higher dissociation threshold, which reflects a tendency to erythrocyte hyperaggregation enhanced by erythropoietin.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical and metabolic characteristics of patients with latent autoimmune diabetes in adults (LADA): absence of rapid beta-cell loss in patients with tight metabolic control.

AIM AND METHODS: The present study compared the clinical and metabolic characteristics of latent autoimmune diabetes in adults (LADA) with type 2 diabetes, as well as the residual beta-cell function and progression to insulin treatment, over a 2-year follow-up period, of antibody (Ab)-positive and Ab-negative patients who achieved tight glycaemic control (HbA(1c) 7.0+/-0.8% and 6.5+/-0.9%, respectively, at the time of entry into the study). RESULTS: Glutamic acid decarboxylase antibodies (GADA) and/or islet cell antibodies (ICA) were detected in 10% of patients presenting with non-insulin-dependent diabetes. Around half of Ab-positive patients required insulin treatment during the follow-up. Ab-positive patients displayed lower stimulated C-peptide levels both at entry and during the follow-up compared with Ab-negative patients, although no significant decline in C-peptide levels was observed in either subgroup over two years. Nevertheless, Ab-positive patients progressed more frequently to insulin treatment, and stimulated C-peptide tended to decrease in LADA patients who subsequently required insulin, whereas it remained stable in those who were non-insulin-dependent. In those who progressed, the trend towards C-peptide decline persisted even after starting insulin treatment. CONCLUSION: LADA patients demonstrate lower residual beta-cell function than do type 2 diabetes patients. However, those who achieve tight metabolic control do not present with a rapid decline in beta-cell function. Further studies are needed to determine the optimal treatment strategy in such patients.

Hemorheology of arterial hypertension: influence of urapidil.

There is an increased prevalence of blood hyperviscosity in patients with arterial hypertension, and viscosity changes are related to hypertensive organ damage such as e.g. left ventricular hypertrophy. Various indices of hemorheology may be assessed in studies of hypertensive patients, most commonly viscosity, erythrocyte filtration, erythrocyte aggregation, platelet aggregation, etc. In vitro assessment of erythrocyte deformability and adrenaline induced platelet aggregation was performed after urapidil administration. Increasing concentrations of urapidil (25-150 microM) caused a dose dependent improvement of the erythrocyte rigidity index as well as inhibited adrenaline induced platelet aggregation. The beneficial effects of urapidil on hemorheology could add to its therapeutic effects in the treatment of arterial hypertension.

[Hyperactivity of the muscles of the lip and chin and indications for surgery to reduce it]. / Dysfonctionnement des muscles labio-mentonniers et indications de la chirurgie d'affaiblissement.

Hyperactivity of the muscles controlling the lower lip and chin (muscles of the chin, buccinator, orbicularis, etc.) can be demonstrated at different levels of the muscular complex and may act as an elastic force against the mandibular alveolar process. Dysfunction in this region may lead to reduction of the alveolar bone quantity, reducing the tooth-bone equilibrium. If this balance is disturbed, periodontal lesions, a lower incisal crowding and a retrognathic mandibular process may result. Surgery to correct overactivity of the chin muscles is described here step by step. Resection of the muscles may be undertaken on a greater or lesser scale and striation of the muscle may also allow reduction of muscular strength. Reducing the muscular activity creates a better environment for the development of the mandible and its alveolar process. Depending on the clinical situation, these techniques can be associated with genioplasty, bone graft and/or mandibular orthognathic surgery.

Ex vivo studies of polymorphonuclear neutrophils from patients with early-onset-periodontitis (II). Chemiluminescence response analysis.

Previous studies have indicated that oxygen-free radicals may cause damage to the periodontal tissues. This study compared the luminol-dependent chemiluminescence response (after stimulation with either opsonized zymosan or phorbol myristate acetate (PMA) of peripheral blood polymorphonuclear leukocytes (PMN) isolated from human subjects with a healthy periodontium (n = 7), gingivitis (n = 8), adult periodontitis (n = 8), or early-onset periodontitis (n = 17). These results were also compared with those obtained in a larger reference group which consists of 50 subjects without infection or inflammation, selected on the basis of laboratory investigations. An enhanced response was defined as being 2 standard deviations above the reference group mean; a reduced response was defined as being 2 standard deviations below this mean. Although PMN from patients with either gingivitis or periodontitis were often functionally activated (when compared to the PMN from the reference group), no significant differences could be found between the 4 groups, with regard to the chemiluminescence response means obtained in a basal state or after stimulation.