[Clinical experiences using modified Schwarz double plates]. / Praktische Erfahrungen bei der Behandlung mit modifizierten Schwarzschen Doppelplatten.

The efficiency of supported double plates according to A.M. Schwarz in the treatment of patients with distocclusion is well-known. When using these appliances we prefer the following procedure: First maxillary and mandibular dentition are treated separately with biomechanically active plates. Then the mandible is adjusted to the normal occlusion but not before the eruption of the first premolars. We attach great importance to the motivation of parents as well as patients for a 12-week intensive co-operation. During this period the patient is expected to wear the appliance 16 to 17 hours per day. It is not necessary for the patient to wear the double-plates at school. The modification of our double plates consists in a U-shaped "Vorbissbügel" (a guidance for protrusive occlusion) with an adequate frontal inclined plan at the mandibular plate.

Effect of diclofenac on plasma levels of immunoreactive prolactin, follicle stimulating hormone, luteinizing hormone, thyrotropin, and beta-endorphin in humans.

Prostaglandins have been shown to modulate the secretion of several pituitary hormones, suggesting that therapeutic doses of nonsteroidal anti-inflammatory drugs may change basal hormone levels. In this study, plasma levels of prolactin, follicle stimulating hormone, luteinizing hormone, thyrotropin and beta-endorphin were determined in 6 healthy men after administration of diclofenac, a prostaglandin synthesis inhibitor. The subjects were given 75 mg intramuscularly and 50 mg orally at 08.00 h the first day, 50 mg orally at 08.00, 12.00 and 20.00 h the second day and an additional 50 mg orally at 08.00 h the third day. Blood samples were collected throughout these 3 days. Diclofenac resulted in a significant and sustained decrease in plasma level of prolactin (p less than 0.005). The other hormones did not demonstrate significant change following diclofenac administration. These data suggest that administration of a prostaglandin synthesis inhibitor, such as diclofenac, selectively alters basal pituitary secretion of prolactin in humans without a detectable effect on plasma levels of other pituitary hormones. This study supports the hypothesis that prostaglandins are necessary for maintaining basal level of prolactin secretion in man.

Thymopoietin and thymopentin enhance the levels of ACTH, beta-endorphin and beta-lipotropin from rat pituitary cells in vitro.

Thymopoietin and thymopentin are well characterized polypeptides influencing immunoregulation by several mechanisms. Proposed as a therapy in diseases with major immune abnormalities such as rheumatoid arthritis, thymopentin improved within 2 weeks some clinical parameters as pain and joint swelling. The hypothesis that this spectacular effect could be mediated through interactions with anti-inflammatory (ACTH) and pain relieving (beta-endorphin) hormones producing cells was tested on the rat isolated pituitary cell model. Thymopentin and thymopoietin can enhance in vitro the levels of ACTH, beta-endorphin and beta-lipotropin in a time- and dose-dependent fashion for physiological concentrations ranging from 10(-12) to 10(-8) mol/l. The action on pituitary cells was restricted to those molecules as no changes occurred in LH, FSH, GH, TSH and PRL levels, after otherwise identical experimental conditions.

In vitro effects of thymopentin on the gamma-interferon production by peripheral blood mononuclear cells from normal subjects and from patients with rheumatoid arthritis.

The in vitro production of gamma-interferon (gamma-IFN) by peripheral blood mononuclear cells (MNC) was measured using a specific radioimmunoassay in 16 patients presenting with active rheumatoid arthritis (RA), in 14 patients with inactive disease, and in 36 control subjects (CS). Unstimulated cultures produced undetectable levels of gamma-IFN and did not incorporate tritiated thymidine. In response to phytohemagglutinin (PHA) 0.2 microgram/ml, MNC from active RA produced 9 times less, and under PHA 2.5 micrograms/ml, 4 times less gamma-IFN than did MNC from inactive RA or from CS. The uptake of tritiated thymidine was, however, similar in the 3 groups. In unstimulated cultures of the 3 groups, thymopentin (TP-5), at all concentrations tested, did not influence either the levels of gamma-IFN or the uptake of tritiated thymidine. In the presence of PHA 0.2 microgram/ml and TP-5, lambda-IFN levels were increased in CS, unchanged in inactive RA and reduced in active RA, whereas no changes were observed in the uptake of tritiated thymidine. Our results show that under our experimental conditions, TP-5 was able to increase the levels of gamma-IFN produced by normal MNC in vitro, but could not reverse the profound defect observed in active RA.

Immunohistochemical localization of HCG and its subunits in testicular germ cell tumours.

Native hCG and its alpha and beta subunits have been localized by immunocytochemistry in 45 testicular germ cell tumours of the testis. Positivity was found for the three molecules in areas with trophoblastic differentiation or in syncytial-like giant cells present in some seminomas. Isolated positivity of hCG alpha was demonstrated in isolated cells usually found in areas of entodermal differentiation of immature malignant teratomas, and probably of neuro-endocrine function. This finding points to genomic derepression in tumour cells and probably also indicates a variability in subunit synthesis and a defect in subunit recombination.

[Human chorionic gonadotropin and its subunits in normal and pathologic pregnancies]. / La choriogonadotrophine humaine et ses sous-unités dans les grossesses normales et pathologiques.

Improved sensitivity and specificity of radioimmunoassays (RIAs) for hCG, hCG alpha and hCG beta have allowed measurements of these substances to become a powerful diagnostic aid applicable to several clinical disorders of pregnancy. In threatened abortion of the 1st trimester, the doubling time of hCG concentrations is significantly slower than in early normal pregnancies. Low levels of hCG are uniformly encountered in case of impending abortion. The overall predictive value of hCG determinations is 75-97%, whereas the predictive value of hCG alpha and hCG beta levels 88%. In patients progressing slowly to inevitable abortion, an increase in hCG alpha and/or the ratio hCG alpha: hCG is frequently observed. In ectopic pregnancies, sensitive new-generation tube tests and RIAs can detect urine or serum hCG in almost 100% of the cases. Abnormally low levels of hCG are encountered in about 85% of the patients. A significant increase in the ratio hCG alpha: hCG is observed. Toxemia of pregnancy is abided by significantly higher maternal levels of serum hCG, hCG alpha and hCG beta and by a lower ratio hPL: hCG than in normal pregnancies, or pregnancies complicated by isolated or chronic hypertension. It is concluded that in the above-mentioned pathological conditions of pregnancy, hCG is a reliable trophoblastic marker and that, additionally, hCG alpha could prove to be an index of chronic placental hypoxia.

[Seasonal variation in the nyctohemeral rhythm of prolactin in cows]. / Variation saisonniére du rythme nycthéméral de la prolactine chez les bovins femelles.

Seasonal variation of prolactin nyctohemeral rhythm has been studied by radioimmunoassay on female cattle of the white blue belgian breed. Animals are divided into three groups as age is concerned : 6 calves, 6 heifers and 5 lactating cows. In december all groups of animals show a significant increase of plasma prolactin concentration between 5 a.m. and 7 a.m. Calves and heifers have a second secretion period either at the end of the afternoon between 17 and 19 p.m. or during the evening between 20 and 23 p.m. The circadian rhythm observed in may with heifers is similar to that in december with two waves whose relative importance is different at the two seasons considered. Nyctohemeral rhythm of prolactin in cattle is age and season dependent.

[Labeling of beta-endorphin and beta-lipotropin with iodine 125]. / Etude du marquage de la beta-endorphine (beta-END) et de la beta-lipotropine (beta-LPH) par l'iode 125.

5 micrograms of human beta-endorphin were labelled with 2 mCi 125I by the chloramine T technique. After two gel filtrations on Sephadex G-15 and on Sephadex G-50 in phosphate buffer with EDTA, Trasylol and mercapto-ethanol, a pure tracer was obtained with a specific activity about 150 microCi/ug. Kept at + 4 degrees C, the tracer remained utilizable for 30 days without loss of immunoreactivity. The labelling with lactoperoxydase and the use of another gel filtration method (filtration on Aca 202) gave a 125I beta-END tracer with the same immunoreactivity. The binding of this tracer to the antibody of an anti-beta-END antiserum diluted at 1/8000 was 32% with a non specific binding of 2%. 5 micrograms of human beta-lipotropin were labelled with 0.5 mCi 125I by the lactoperoxydase method. After two gel filtrations on Sephadex G-25 and on Sephadex G-75 in phosphate buffer with EDTA, Trasylol and mercapto-ethanol, a pure tracer with a specific activity of 140 microCi/micrograms was obtained. It remained utilizable for 30 days when kept at + 4 degrees C. Gel filtration on Aca 202 did not give good purification, while gel filtration on Aca 54 was good but slower than on Sephadex G-75. The binding to antibody in absence of unlabelled beta-LPH was 32% for an anti-beta-LPH antiserum diluted at 1/4000. The non specific binding was 2.5%.

Serum concentrations of human chorionic gonadotrophin and its alpha and beta subunits. 1. During normal singleton and twin pregnancies.

Homologous radioimmunoassays have been developed for native hCG and its alpha and beta subunits. Their specificities were assessed by analysis of the inhibition ca and beta subunits. 1. During normal singleton and twin pregnancies.

Serum concentration of human chorionic gonadotropin and its alpha and beta subunits. 2. Trophoblastic tumours.

Using specific homologous radioimmunoassays of native hCG and its alpha and beta subunits, we determined the levels of these glycoproteins in unfiltered maternal blood serially obtained in five non-invasive hydatidiform moles before and after evacuation. Some of these samples were assayed after gel filtration chromatography on Sephadex G 100. Twelve samples, obtained in cases of invasive trophoblastic tumour after ablative surgery and chemotherapy, were also assessed for their hCG, hCG alpha and hCG beta content. In unaborted moles, mean circulating levels of native hCG and free hCG beta were considerably increased (seven and thirteen times, respectively) as compared to normal pregnancies of the same age, whereas levels of free hCG alpha were either normal or slightly elevated. Chromatographic analyses of molar sera confirmed the presence of free circulating subunits, and separated hCG beta in its monomeric form from its higher molecular weight form, the latter being in greater quantity than in normal pregnancy sera. In contrast, the elution profile of serum native hCG was comparable in cases of normal and molar pregnancy. Successful curettage was accompanied by a return to normal levels of the native hCG and its alpha and beta subunits in 40-90 days. Persistence of tumour tissue was indicated by a slight increase in levels of native hCG and the beta subunit. Determination of alpha subunit level was less useful for the detection of any relapse.

Immunofluorescent localization of placental lactogen, chorionic gonadotrophin and its alpha and beta subunits in organ cultures of human placenta.

Localization of human placental lactogen (HPL), chorionic gonadotrophin (HCG) and its free alpha and beta subunits in mature and immature placental villi before and during organ culture was examined with an 'indirect' immunofluorescent technique using highly specific antisera. HPL fluorescence was strictly localized to the syncytiotrophoblast and the intensity of this fluorescence increased with gestational age and decreased with the time of culture. Undissociated HCG and HCG beta immunofluorescence was localized to the syncytiotrophoblast. Maximum intensity was observed in immature placentae and was not significantly affected by the duration of culture. However, irregular and patchy HCG and HCG beta immunofluorescence was seen in the cytotrophoblasts under conditions of extensive syncytiotrophoblastic damage. HCG alpha immunofluorescence was localized in the syncytiotrophoblast of immature placentae and was more intense in mature placentae. Beginning the third day of culture, HCG alpha fluorescence increased and was also present in the cytotrophoblast. On the basis of these observations and additional data, the possibility is discussed that cytotrophoblastic cells, better preserved than the syncytiotrophoblast in case of restricted energy and oxygen supply, may actively synthesize free HCG alpha, in addition to syncytiotrophoblastic production of this subunit. By contrast, HPL, undissociated HCG, and HCG beta are mainly or exclusively eleborated in the syncytiotrophoblastic layer.

[Maternal serum levels of chorionic gonadotropin and its alpha and beta free subunits as a function of the fetal sex. Preliminary study]. / Taux sériques maternels de la choriogonadotrophine et de ses sous-unités libres alpha et bêta en fonction du sexe foetal. Etude préliminaire.

The maternal serum levels of hCG and its alpha or beta subunits were measured in 96 normal pregnancies and correlated with the fetal sex. During the first 20 weeks (69 cases), the maternal serum levels of hCG, of its alpha subunit and particularly of its beta subunit were higher in cases of female fetuses. However no statistically significant difference was observed between the levels of hCG or its subunits in serum of pregnancies with male or female fetuses. During the second half of pregnancy, the serum hCG levels were discretely higher in cases with female fetuses (no significant difference) and the serum levels of its alpha or beta subunits were identical in cases of male of female fetuses.

[Cellular receptors of gonadotropic hormones. Immunocytochemical evidence in rat testicle]. / Récepteurs cellulaires aux hormones gonadotropes. Mise en évidence par immunocytochimie dans le testicule du rat.

We have performed topical applications of HCG and LH on fixed paraffin-embedded sections of adult rat testes. Thereafter, immuno-cytochemical demonstration of the peptides was carried on and demonstrated that HCG and LH specifically bound to the cell membrane of Leydig cells. This technique is highly reproductible provided that adequate fixation (with formalin containing fixatives) as been performed.

[Fate of Leydig cells in testicular organ culture]. / Le devenir des cellules de Leydig du testicule en culture organotypique.

In organ culture experiments, the Leydig cells of mouse testes can still be recognized after 12 days at 31 degrees C. HCG binding sites are effectively demonstrated. Meanwhile, when HCG is added at the initiation of the cultures, it is selectively stored in the cytoplasm of the Leydig cells. These findings point to a fairly good survival of Leydig cells in our tissue culture system.