Analyse comparative de 3 logiciels de reconstruction itérative de tomoscintigraphie monophotonique myocardique

ObjectiveThis study makes a comparative analysis of the quality reconstruction of three software: 2D ordered subset expectation maximisation (2D OSEM), 3D ordered subsets expectation maximisation (Flash 3D) and Wallis.Patients and methodsThe data from myocardial scintigraphy acquisitions of 50 patients (38 men and 12 women; average age 61 ± 9 years) were successively reconstructed using three myocardial perfusion SPECT algorithms (Flash 3D, OSEM 2D and Wallis). Different combinations of iterations and subsets were considered. For Wallis, only the cut-off frequency was considered. The image's quality was assessed by determining the maximum contrast and the signal to noise ratio.ResultsThe Wallis software provided a higher signal to noise ratio compared to Flash 3D and OSEM 2D at stress and rest. The Wallis signal to noise ratio increased by a factor 1.93 (P = 0.0010) and 2.28 at stress (P = 0.0009); 1.50 (P = 0.0011) and 2.84 at rest (P = 0.0024) compared to respectively Flash 3D and OSEM 2D. Flash 3D provided better signal to noise ratio than OSEM 2D at stress and at rest. The difference in medians and interquartile ranges of the signal-to-noise ratio in post-stress were 22 % and 54 %, respectively between Flash 3D and OSEM 2D. At rest, the difference between the two methods in signal to noise ratio was 32 % ± 0.,29.ConclusionWallis algorithm was improve image quality with better signal to noise ratio compared to the reference method of Siemens Flash 3D. For both Flash 3D and OSEM 2D methods, the combination with 8 subsets and 12 iterations provided the best contrast and signal to noise ratio.     

Évaluation de la sidération myocardique post-effort immédiat par tomoscintigraphie myocardique au 99mTc-sestamibi couplée à l’ECG

AimRepeated episodes of myocardial stunning may lead to chronic ventricular dysfunction. We attempted to assess the parameters related to post-exercise stunning in patients undergoing gated SPECT.MethodsSix hundred patients undergoing a one-day stress/rest ^99mTc-sestamibi gated SPECT were studied. Stress imaging was acquired within 15 minutes after injection. Summed perfusion scores (SSS, SRS and SDS) were calculated using QPS, and LV function assessed using QGS. Stunning was defined as the association of ischemia (SSS ≥ 4 and SDS > 0) and a minimum of 5% decrease in post-stress EF.ResultsIschemia was found in 225 (37.5%) patients. Among these, 67 (30%) showed myocardial stunning. Patients with stunning had a lower rest ESV (47 ± 24 mL vs 65 ± 52 mL, p < 0.0003) and EDV (108 ± 35 mL vs 122 ± 66 mL, p = 0.03), an increased rest LVEF (58 ± 10% vs 52 ± 13%, p < 0.0001) and a decreased post-stress LVEF (49 ± 10% vs 53 ± 13%, p < 0.02) compared to patients with no stunning. The number of myocardial segments showing reversible perfusion defects was increased in patients with stunning (2.7 ± 2.6 vs 1.7 ± 2.1, p < 0.02). On logistic regression, an extent of ischemia greater than two segments and a rest EF greater than 45% were independent predictors of the occurrence of myocardial stunning in patients with ischemia.ConclusionsIn patients with ischemia, exercise-induced stunning was associated with an increased extent of ischemia but also preserved rest ventricular function.     

Évaluation de la faisabilité de la tomoscintigraphie myocardique précoce au sestamibi synchronisée à l’électrocardiogramme

BackgroundOur aim was to assess the feasibility of early acquisition (10 min) gated single photon emission computed tomography (SPECT) by comparison to conventional imaging at one hour.Methods and resultsOne hundred and four patients referred for exercise test and SPECT were included. Sequential imaging was started 10 min (SPECT 10) and 60 min (SPECT 60) after injection of the radiotracer (Tc-99m sestamibi). Stress myocardial perfusion was visually analyzed from 10 to 60 min stress by two experienced nuclear-cardiologists. Six patients were further excluded, because of high digestive accumulation: one patient at 10 min, three at 10 and 60 min, two at rest. The participants were classified as follows: group G1 (normal SPECT 10 and 60, n = 53), group G2 (abnormal SPECT 10 and/or SPECT 60, n = 45). The left ventricle ejection fraction (EF) and volumes (end-systolic and end-diastolic volumes, ESV, EDV) were calculated with the Cedars-Sinai program.ResultsQuality imaging was the same at SPECT 10 min and SPECT 60 min. Perfusion scores: G1 10 min = 0,4 versus G1 60 min = 0,4 (p = NS); G2 10 min = 10,2 versus G2 60 min = 10,1 (p = NS); EFG1 10 min = 71 ± 11% versus EFG1 60 min = 68 ± 10% (p = 4E-04); EFG2 10 min = 56 ± 15% versus EFG2 60 min = 53 ± 15% (p = 0,002); EDV G1 10 min = 72 ± 20 ml versus EDV G1 60 min = 76 ± 19 (p = 0,002); EDV G2 10 min = 98 ± 46 ml versus EDV G2 60 min = 105 ± 38 (p = 0,08); ESVG1 10 min = 22 ± 12 m versus ESV G1 60 min = 25 ± 12 (p = 9E-04); ESVG2 10 min = 47 ± 35 ml versus ESV G2 60 min = 53 ± 36 (p = 3E-04).ConclusionsThis study suggests that early gated Sestamibi SPECT after stress provides same perfusion analysis than classical late imaging.     

Scintigraphie myocardique et séquelles de myocardite : présentation d’un cas clinique

Acute and subacute myocarditis are well-defined pathological entities but it is often difficult to identify them because their clinical expression is variable and the diagnosis is histological showing myocardial inflammation associated with degeneration and/or necrosis. Often symptoms are similar to those of acute pericarditis with “chest-crushing” pain that mimics myocardial infarction and prompts practitioners to request angiography, especially when there are cardiovascular risk factors. We report the case of a 61-year-old patient with neither cardiac history nor cardiovascular risk factor who consulted for a long and self-limited atypical chest pain with normal clinical examination and electrocardiogram. Myocardial perfusion scintigraphy showed a non-reversible photopenic area suspected of being a nontransmural necrosis or an artifact. The discovery of inferolateral hypokinesis of left ventricle on echocardiography led to perform a coronary angiography which was finally normal. Cardiac MRI allowed to diagnose scars of a previous episode of myocarditis.     

L’analyse combinée de la tomoscintigraphie myocardique de stress et de l’angioscanner coronaire pour identifier les artères responsables de l’ischémie

The identification of ischemia-related coronary artery by stress myocardial perfusion SPECT (SPECT-MPS) is difficult, but it is likely that this identification could be easier by fusionning the SPECT images with images from coronary CT angiography (CTA).ObjectiveTo assess the usefulness of the fusion of SPECT-MPS images with CTA images in the identification of ischemia-related coronary arteries.MethodSPECT-MPS and CTA, which had been recorded in a delay ≤ 3 months, were reanalyzed blindly to identify the coronary arterial vessels with (1) stress ischemia at SPECT-MPS and (2) significant coronary stenosis (> 70 %) at CTA. In case of discordance between the two techniques, an analysis was performed while fusioning the SPECT-MPS and CTA images.ResultsThe population included 38 patients, of whom 22 (58 %) had an ischemia at SPECT-MPS. The identification of the ischemia-related vessels was initially discordant between SPECT-MPS and CTA for 17 patients (45 %). After the fusion's analysis, nine out of these 17 patients (53 %) became totally concordant because of modifications in the CTA analysis in six patients and in the SPECT-MPS analysis in only three. A low severity of ischemia was the main correlate of persisting discordances after fusion: 58 % (7/12) of such low severity ischemia were observed in coronary vessels with persisting discordance, but only 24 % (5/27) with concordant coronary vessels (p = 0.02).ConclusionThe identification with SPECT-MPS of the ischemia-related coronary artery is rarely modified by a fusion analysis with CTA images. Discordances between the two techniques remain frequent, even after fusion, but especially in case of low severity SPECT-MPS ischemias.     

Intérêt de la tomoscintigraphie cardiaque à la 123I-mIBG couplée à la perfusion myocardique dans le diagnostic de l’atrophie multisystématisée

ObjectiveThe aim of this prospective study is to assess the pertinence of using ¹²³I-mIBG myocardial tomoscintigraphy coupled with perfusion scintigraphy as a diagnostic tool, to discriminate between multiple system atrophy (MSA) and idiopathic Parkinson's disease (PD) at first guided by clinical data and L-DOPA tests.Material and methodsForty patients, aged from 43 to 78 years (median 62 years) with Parkinson's syndrome were studied. Nineteen had a diagnosis of PD (criteria of brain bank) and 21 AMS (Gibbs criteria). All were given test to acute L-DOPA. Chest-centered planar imaging (128 × 128 matrix, 5 minutes of duration) is performed at 1 hour and 4 hours after injection of 220 MBq of ¹²³I-mIBG, in addition a non-synchronised tomoscintigraphy (64 × 64 matrix, 32 images of 50 seconds , zoom 1.45) was performed after the 4th hour and 15 minutes after injection of 200 to 400 MBq of ^99mTc-tetrofosmin. Besides neurological data, the parameters retained for comparison purposes with ¹²³I-mIBG cardiac tomoscintigraphy were patients’ age, duration of disease and L-DOPA test results. Two regions of interest (ROI) identical in size and in shape are used for ¹²³I-mIBG uptake quantifications (H/M and washout [Wo]). The first one was placed in projection of mediastinum (M) and the other one in projection of heart (H).ResultsWe found an overall decreased uptake of the myocardial ¹²³I-mIBG without perfusion abnormality in 15 of 19 patients with PD and 11 among them were L-DOPA sensitive (L-DOPA test greater than 30%). Normal tracer uptake with ¹²³I-mIBG associated with an almost quite normal perfusion was seen in 15 of 21 patients with MSA and they were little or not L-DOPA sensitive (L-DOPA test less than 30%). Therefore, 10 discordant cases (25%) between cardiac scintigraphy and clinical evolution of disease with also discordant L-DOPA tests were observed. In the PD group, quantification of data enhanced the diagnostic decision with low heart to mediastinum ratio (H/M) (1.32 ± 0.15 at the early stage and 1.25 ± 0.13 at the later stage). In the MSA group, the uptake of ¹²³I-mIBG (1.66 ± 0.43 at the early stage and 1.72 ± 0.42 at the later stage) was comparable to literature data, however, with significant inter-individual variations. The association of data of scintigraphy with L-DOPA test allows to improve sensitivity in 84% and specificity in 90.5%.ConclusionOur prospective study of 40 cases shows the relevance of cardiac sympathetic postganglionic imaging with ¹²³I-mIBG coupled with myocardial perfusion scintigraphy to discriminate between MSA and PD with a higher sensitivity (71.4%) compared to the test with L-DOPA but a lower specificity (78.9%) than the L-DOPA. The difficulty of diagnosis is firstly linked to damage occurring to both the pre- and postganglionic sympathetic systems in patients with MSA and secondly to the integrity of the sympathetic nerve endings in patients with PD. However, the association of data of scintigraphy with L-DOPA test show a significant improvement of sensibility (84%).     

Facteurs influençant la détectabilité de l’activité myocardique en caméra à semi-conducteurs

Body weight was already shown to be a major factor for the detectability of myocardial activity with conventional cameras and thus, for the optimization of injected activities and or recording times. This study was aimed to identify the factors affecting this detectability on a new solid-state camera showing a high sensitivity of detection (D.SPECT camera Cyclopharma^®).Patients and methodsThe study population involved 101 patients, who underwent myocardial SPECT with Sestamibi on a one-day stress/rest protocol. Each conventional acquisition (DST-XL General Electric Healthcare^® USA) was immediately followed by a D-SPECT^® one. Myocardial activity was determined on each acquisition in counts per seconds and expressed in fraction of the injected activity for assessing the detectability of myocardial activity.ResultsMyocardial activity was on average 12 ± 3 fold higher when recorded with the D-SPECT^® camera than with the DST-XL^® one. Body weight and especially body mass index (BMI) were the most significant correlates of the detectability of myocardial activity for both cameras. According to these correlations, an increase in the BMI from 25 to 35 kg/m was associated with a 47% decrease in the detectability of myocardial activity at stress with the DST-XL^® and of only 30% with the D-SPECT.ConclusionThe detectability of myocardial activity provided by the D.SPECT camera is dramatically higher than that documented for conventional cameras of the DST-XL^® type and is affected by the increase in body weight and in body mass index but at a lower rate than for the Anger camera.     

Étude de l’impact d’une correction d’atténuation par tomodensitométrie en scintigraphie myocardique

Myocardial perfusion SPECT is a routine for the assessment of patients with coronary artery disease (CAD). However, attenuation artifacts may decrease the specificity of the test. These artifacts can be corrected with an attenuation correction. We prospectively included 70 patients who underwent myocardial perfusion SPECT with (IRAC) and without (IRNC) attenuation correction using transmission CT imaging integrated in the acquisition system in patients with low prevalence of CAD. Automatic quantitative analysis with summed stress score (SSS) and rest (SRS) and summed difference score (SDS) was used as interpretation criteria. The results showed a specificity of 80% for IRAC and 56% for IRNC, a positive predictive value of 40% for IRAC and 23% for IRNC, without any significant change in sensitivity. An unpaired t-test showed no significant difference between the overall population and one where an artifact was corrected for heart rate and breath rate during the acquisition effort, the body mass index, chest and abdomen circumferences, and the ratio of these two parameters. Attenuation correction significantly improves the specificity of myocardial scintigraphy with no significant difference in sensitivity. The majority of corrections were for artifacts from the inferior wall in men. There is no correlation between the anthropomorphic and physiological parameters and the occurrence of an artifact of attenuation corrected with CT data.     

Taux de fixation de la pointe du ventricule gauche et correction d’atténuation TEMP/TDM dans la scintigraphie myocardique de perfusion chez les patients non ischémiques

Introduction

Attenuation correction (AC) has been shown to improve the accuracy of myocardial perfusion single photon emission computed scintigraphy (SPECT). It often reveals a decrease in apical uptake in the AC of the left ventricular (LV) in non-ischemic patients. We aimed to identify the parameters that could affect the apical radiotracer uptake in non-ischemic patients.

Évaluation de la cinétique globale et segmentaire du ventricule gauche chez les patients connus ou suspects de cardiopathie ischémique : comparaison des données apportées en scintigraphie de perfusion myocardique et en tomoventriculographie isotopique

Background and aimsThe analysis of the left ventricular contractile function plays a major role in the diagnosis and management of patients with cardiopathies. The aim of our study was to compare gated blood pool SPECT and myocardial perfusion scintigraphy for the assessment of the left ventricular wall contractility at the global and the segmental scales.Material and methodsThe data of 23 ^99mTc-Tetrofosmin perfusion scintigraphies, and 50 ²⁰¹Thallium perfusion scintigraphies were compared to those of gated blood pool SPECT performed at close interval.ResultsThe correlations were good (r = 0.81 to 0.94) concerning the global parameters (left ventricular ejection fraction, end-diastolic and end-systolic volumes) in the two groups. Quite good correlations were also found at the segmental scale (r = 0.49 to 0.62), between the segmental ejection fraction calculated in gated blood pool SPECT and the wall thickening or the wall motion estimated in perfusion scintigraphy. These correlations were significantly lower in the “²⁰¹Thallium perfusion scintigraphy” group than in the “^99mTc-Tetrofosmin perfusion scintigraphy” group, especially for hypokinetic segments.ConclusionAlthough they use very different approaches, GBPS and MPS give data about global and segmental left ventricular wall contraction that are well correlated, but not strictly interchangeable.     

A propos de l'intervention des aéroions dans les processus de régulation de la lipémie et de la cholestérolémie

Resume Les expériences ont porté sur des lapins repartis en deux groupes parallèles — un groupe étant traité avec des aéroions négatifs en concentrations moderées (n^– = 10 – 40.000; n⁺ = 1.000) et l'autre sans aéroionothérapie (témoins). Par rapport aux animaux témoins (pas exposés aux aéroions),on a enregistré,sous l'influence de l'aéroionothérapie, que: (1)il y a une tendence de normalisation de la motilité spontanée, deprimée par une alimentation contenant un excès de cholestérol(0,3 g/kg/jour); (2) la lipémie et la cholestérolémie sont restées à un niveau plus bas chez les animaux alimentés au cholestérol; (3) la lipémie et la cholestérolémie, de même que l'iode thyroïdien, sont restées aux valeurs voisines de celles normales,chez les animaux nourris avec un excès (20 mg/kg/jour), de substances antithyroïdiennes naturelles (provenant du chou).

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Groups of rabbits were exposed to negative air ions of moderate concentrations (n^– = 10 – 40,000; n⁺ = 1,000) while others served as controls. (1) When rabbits were fed a cholesterol-rich diet (0.3 g/kg/day)causing reduction of motility in the control animals, their motility was normalized under air ion treatment. (2) The blood cholesterol and lipid levels of rabbits on a cholesterol-rich diet were lower with air ion treatment than in controls.(3) When rabbits were fed a diet with thyroid blocking agents from cabbage the blood cholesterol and lipid levels and the thyroid iodine content remained unchanged with air ion treatment.

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Zusammenfassung Gruppen Kaninchen wurden mit negativen Luftionen in mässigen Konzentrationen (n^– = 100 000 – 40 000; n⁺ = 1 000) behandelt, während andere als Kontrollen dienten. (1) Die durch Fütterung von cholesterinreicher Diät (0,3 g/kg/Tag) verminderte Motilität der Tiere wurde unter der Luftionenbehandlung normalisiert. (2) Der durch Fütterung von cholesterinreicher Diät erhöhte Blutcholesterin- und-fettspiegel fiel durch Luftionenbehandlung ab. (3) Der durch Fütterung von strumipriven Substanzen aus Kohl erhöhte Cholesterin- und Fettspiegel im Blut und verminderte Jodgehalt der Schilddrüse wurde durch Luftionenbehandlung nicht beeinflusst.

     

Étude de deux cent-cinquante souches de bacilles hétérolactiques isolés de vins

Résumé Les auteurs ont isolé plus de 700 souches de bactéries lactiques à partir de raisins, de moûts, de vins de diverses origines et à différents stades de conservation. Ils étudient ici 253 souches de bacilles hétérofermentaires, dans le but d'établir une classification simple et un catalogue permettant un repérage facile des souches.Il est commode de classer les souches d'après la fermentation des pentoses, en raison de la netteté de ces tests, alors que parfois ceux appliqués à d'autres sucres ont des caractères moins tranchés. On retrouve alors la classification qui avait été déjà donnée par Vaughn, Douglas et Fornachon en 1949.Les bacilles pentoses négatifs (26 souches) forment l'espèce Lactobacillus fructivorans. Ceux qui font fermenter seulement l'arabinose (4 souches) ou seulement le xylose (155 souches) correspondent respectivement à Lactobacillus desidiosus et à Lactobacillus hilgardii. L'espèce Lactobacillus brevis comprend les bacilles pentoses positifs (68 souches).

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A study of two hundred and fifty strains of lactic acid bacteria

Summary The authors have isolated more than 700 strains of lactic acid bacteria found in grapes, musts and wines of various origins and at different states of conservation. They study in this work 253 strains of heterofermentative bacilli in order to work out a classification and a catalogue allowing easy identification of the strains.It is convenient to classify the strains from the fermentation of pentoses, on account of the accuracy of these tests, tests on other sugars having sometimes less specific characters. The results are consistant with the classification already established by Vaughn, Douglas and Fornachon in 1949.Pentose negative bacilli (26 strains) constitute the species Lactobacillus fructivorans. The ones which ferment only arabinose (4 strains) or only xylose (155 strains) correspond to Lactobacillus desidiosus and Lactobacillus hilgardii. The pentose positive strains (68) belong to the species Lactobacillus brevis.

     

Absence de corrélation génotype-phénotype dans les absences de canaux déférents

Absence of the vas deferens is a rare cause of male infertility, associated with mutations in the cystic fibrosis transmembrane regulator (CFTR) gene in about 80% of cases. Only limited published data are available concerning the correlation between genotype and reproductive tract abnormalities observed in this disease: presence or absence of seminal vesicles and parts of the epididymis, symmetrical or asymmetrical lesions, testicular volumes. We screened 47 patients for the 13 most common CFTR mutations on the cystic fibrosis gene and for the 5-thymidine variant of the polythymidine tract of intron 8. Renal, scrotal and transrectal ultrasonography was performed in each patient to explore the testes and reproductive tract. All patients presented absence of the ampullae of the vas deferens. Forty patients presented bilateral absence of the vas deferens and 7 presented unilateral absence of the vas deferens. At least one mutation of the cystic fibrosis gene was present in 64% of cases: 47% had the ΔF 508 mutation and 63% had the 5T allele. No mutation was detected in seventeen patients, including 3 patients with unilateral renal agenesis and 3 patients with unilateral absence of the vas deferens. No differences were observed for seminal vesicles and symmetry of vesicular and epididymal abnormalities between patients with or without CFTR gene mutations, but epididymal abnormalities were significantly more frequent in the group without mutation (p=0.01). Testicular volumes were significantly lower in the patients without mutation or with the 5T allele only, than in the patients with at least one CFTR gene mutation: 10.7±4.1 ml versus 15.1±4.5 ml, respectively (p<0.001). In conclusion, in cases of isolated absence of the vas deferens, there is no difference in sperm duct abnormalities between patients with or without CFTR gene mutation. These results suggest that other genetic or environmental determinants are required to explain a common pathogenesis for these malformations. The decreased testicular volume of patients without CFTR gene mutation or with the 5T allele only suggests the existence of an unidentified secretory or mixed factor involved in these forms of absence of the vas deferens.     

Variations de l'incidence des fractures de l'extrémité supérieure du fémur chez les personnes agées de la région de Québec.

To estimate the incidence of fracture of the proximal end of the femur in people aged 50 years or older living in the Quebec area in 1971, 1976 and 1981 we determined the number of admissions for such fractures to the 15 acute care hospitals in the region. From 1971 to 1981 the number of fractures increased by 71%; the increases for those aged 75 to 84 years and 85 years or over were 98% and 118% respectively. The variation is only partly explained by changes in sex and age distribution of the population; the incidence rates also increased. Among men aged 75 to 84 years the incidence rate per 1000 person-years rose from 2.63 in 1971 to 5.22 in 1981, an increase of 98%; the corresponding figures for men aged 85 years or more were 9.76 and 16.91, an increase of 73%. Among women aged 75 to 84 years the rate rose from 7.28 to 8.81, an increase of 21%; the corresponding figures for women aged 85 years or more were 20.40 and 24.27, an increase of 21% and 19% respectively.     

Le comportement de la cellule végétale en présence de toxiques additionnés de substances tensio-actives

Résumé Le présent travail expose quelles sont les réactions de la cellule végétale lorsque cette dernière est soumise à l'association d'un toxique et d'un « mouillant » (Netzmittel).Les variables sont: la nature de la cellule végétale, celle du toxique et celle du mouillant.Alors que les mouillants cationiques, eux-mêmes toxiques, exercent une simple action additive, les mouillants anioniques révèlent dans de nombreux cas une synergie de toxicité. Celle-ci se manifeste surtout avec les champignons et les bactéries Gram+, les végétaux supérieurs se montrant indifférents. Cette synergie varie également avec la structure moléculaire du mouillant.Les mouillants non ioniques peuvent au contraire exercer une action antagoniste, c'est-à-dire diminuer la toxicité.Ce dernier phénomène se produit dans certains cas à la suite d'une réaction chimique entre le mouillant et le toxique; la nature de la cellule est alors indifférente. Dans d'autres cas, il y a absence de réaction chimique et le phénomène ne se produit qu'avec certains types de cellules (champignons surtout).La nature chimique du toxique joue, dans la synergie, un rôle moins important que dans l'antagonisme.Des hypothèses sont formulées pour tenter d'élucider le mécanisme des cas de synergie et d'antagonisme.     

Le syndrome de kallmann de morsier aspect génétique

Kallmann syndrome (KS) is a rare, heterogeneous disorder consisting of congenital hypogonadotropic hypogonadism, associated with anosmia (or hyposmia) and other clinical manifestations such as mirror movements, and renal, urological and neurosensory disorders. The presence of anosmia with micropenis in boys is suggestive of the diagnostic of KS. In KS, the GnRH neurons do not migrate correctly from the olfactory placode to the hypothalamus during development and olfactory bulbs also fail to form, leading to anosmia. Mutations in KAL1 which encodes Anosmin-1, are responsible for the X-linked form of KS. Anosmin-1 is normally expressed in the brain, facial mesenchyme, mesonephros and metanephros. It is required to promote migration of GnRH neurons into the hypothalamus. It also allows migration of olfactory neurons from the olfactory bulbs to the hypothalamus. The loss of function mutations in FGFR1 “fibroblast growth factor” were identified in 2003 as a cause of autosomal forms of this disease. An additional autosomal cause of Kallmann syndrome was recently identified by a mutation in the prokineticin receptor-2 gene (PROKR2) (KAL-3) and its ligand prokineticin 2 (PROK2) (KAL-4). Mutations in these genes induce various degrees of olfactory and reproductive dysfunction, but not the other symptoms seen in KAL-1 and KAL-2 forms of KS. Neuropilin2, which has an important role in migration of GnRH neurons, is a recent candidate gene for KS. The authors describe the genetic features and recent findings of KS, necessary to understand this disease.     

Changements de l'epithélium médian des bourgeons palatins de souris au stade de préfusion

Résumé Avant d'entrer en contact, les surfaces de fusion des processus palatins subissent des modifications. Certaines cellules épithéliales superficielles deviennent turgescentes, alors que d'autres conservent un aspect dense et aplati, elles se lysent et éclatent. Des noyaux semblables à ceux des assises profondes se retrouvent en surface, paraissant migrer vers le bourgeon antagoniste. Des projections filamenteuses apparaissent, quelques unes établissant un contact avec l'épithélium opposé, d'autres restant seulement sous forme d'expansion. Ces observations sont concordantes en microscopie photonique et en microscopie électronique à balayage.

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Modification of the medial epithelium of the palatal shelves of mice at the prefusion stage. A light and scanning electron microscopy study

Summary The fusion surfaces of the palatal processes are modified before coming into contact. Several superficial epithelial cells become hypertrophied, undergo lysis and burst, whereas others remain flattened and densely stained. Nuclei, similar to those localized in deeper layers are found on the surface and seem to migrate towards the opposite process. Filamentous projections appear and some establish a linkage with the opposite epithelium, whereas others expand freely from the surface. Light microscope observations agree with scanning electron microscopy findings.