Symmetric pollen mitosis I and suppression of pollen mitosis II prevent pollen development in Brachiaria jubata (Gramineae)

Microsporogenesis and pollen development were analyzed in a tetraploid (2n = 4x = 36) accession of the forage grass Brachiaria jubata (BRA 007820) from the Embrapa Beef Cattle Brachiaria collection that showed partial male sterility. Microsporocytes and pollen grains were prepared by squashing and staining with 0.5% propionic carmine. The meiotic process was typical of polyploids, with precocious chromosome migration to the poles and laggards in both meiosis I and II, resulting in tetrads with micronuclei in some microspores. After callose dissolution, microspores were released into the anther locule and appeared to be normal. Although each microspore initiated its differentiation into a pollen grain, in 11.1% of them nucleus polarization was not observed, i.e., pollen mitosis I was symmetric and the typical hemispherical cell plate was not detected. After a central cytokinesis, two equal-sized cells showing equal chromatin condensation and the same nuclear shape and size were formed. Generative cells and vegetative cells could not be distinguished. These cells did not undergo the second pollen mitosis and after completion of pollen wall synthesis each gave rise to a sterile and uninucleate pollen grain. The frequency of abnormal pollen mitosis varied among flowers and also among inflorescences. All plants were equally affected. The absence of fertile sperm cells in a considerable amount of pollen grains in this accession of B. jubata may compromise its use in breeding and could explain, at least in part, why seed production is low when compared with the amount of flowers per raceme.

Participation of the cholinergic system in the ethanol-induced suppression of paradoxical sleep in rats

Sleep disturbance is among the many consequences of ethanol abuse in both humans and rodents. Ethanol consumption can reduce REM or paradoxical sleep (PS) in humans and rats, respectively. The first aim of this study was to develop an animal model of ethanol-induced PS suppression. This model administered intragastrically (by gavage) to male Wistar rats (3 months old, 200-250 g) 0.5 to 3.5 g/kg ethanol. The 3.5 g/kg dose of ethanol suppressed the PS stage compared with the vehicle group (distilled water) during the first 2-h interval (0-2 h; 1.3 vs 10.2; P < 0.001). The second aim of this study was to investigate the mechanisms by which ethanol suppresses PS. We examined the effects of cholinergic drug pretreatment. The cholinergic system was chosen because of the involvement of cholinergic neurotransmitters in regulating the sleep-wake cycle. A second set of animals was pretreated with 2.5, 5.0, and 10 mg/kg pilocarpine (cholinergic agonist) or atropine (cholinergic antagonist). These drugs were administered 1 h prior to ethanol (3.5 g/kg) or vehicle. Treatment with atropine prior to vehicle or ethanol produced a statistically significant decrease in PS, whereas pilocarpine had no effect on minutes of PS. Although the mechanism by which ethanol induces PS suppression is not fully understood, these data suggest that the cholinergic system is not the only system involved in this interaction.

Kaurene diterpene induces apoptosis in U87 human malignant glioblastoma cells by suppression of anti-apoptotic signals and activation of cysteine proteases

Gliomas are the most common and malignant primary brain tumors in humans. Studies have shown that classes of kaurene diterpene have anti-tumor activity related to their ability to induce apoptosis. We investigated the response of the human glioblastoma cell line U87 to treatment with ent-kaur-16-en-19-oic acid (kaurenoic acid, KA). We analyzed cell survival and the induction of apoptosis using flow cytometry and annexin V staining. Additionally, the expression of anti-apoptotic (c-FLIP and miR-21) and apoptotic (Fas, caspase-3 and caspase-8) genes was analyzed by relative quantification (real-time PCR) of mRNA levels in U87 cells that were either untreated or treated with KA (30, 50, or 70 µM) for 24, 48, and 72 h. U87 cells treated with KA demonstrated reduced viability, and an increase in annexin V- and annexin V/PI-positive cells was observed. The percentage of apoptotic cells was 9% for control cells, 26% for cells submitted to 48 h of treatment with 50 µM KA, and 31% for cells submitted to 48 h of treatment with 70 µM KA. Similarly, in U87 cells treated with KA for 48 h, we observed an increase in the expression of apoptotic genes (caspase-8, -3) and a decrease in the expression of anti-apoptotic genes (miR-21 and c-FLIP). KA possesses several interesting properties and induces apoptosis through a unique mechanism. Further experiments will be necessary to determine if KA may be used as a lead compound for the development of new chemotherapeutic drugs for the treatment of primary brain tumors.

Lettre à un ami sur la suppression de l'habit ecclésiastique, & sur le danger que court le clergé de France, de pertes plus réelles ([Reprod.])

Collection : Les archives de la Révolution française ; 8.262

Edit du Roy, portant suppression des offices de contrôlleurs des bans de mariage qui avoient esté créez par l'Edit du mois de septembre 1697 . Et tarif des droits que Sa Majesté veut estre payez à l'avenir pour le contrôlle & l'enregistrement de chacune publication de ban de mariage conformement audit Edit. Donné à Versailles au mois de mars 1702. Registré en Parlement le 26 avril 1702.

[Acte royal. 1702-03-00. Versailles]

Arrêt du conseil d'Etat qui commet J.-B. Dumont pour l'exécution de l'Edit de janvier 1717, portant suppression des offices de contrôleurs des greffiers garde-minutes des chancelleries près les cours et sièges présidiaux

[Acte. 1717-02-20. Paris]

Édit... portant suppression des offices de conseillers du Roy notaires et secrétaires dans les cours de Parlement, Chambres des Comptes et Cours des Aydes, Grand Conseil, Requestes de l'Hostel et du Palais, Conseils supérieurs et provinciaux, Cours des monnoies et Bureaux des Finances ; ordonne que les greffiers en chef des cours seront tous tenus de se pourvoir de l'un des offices de secrétaires, créez dans les chancelleries près les Cours par édit... de juin 1715 ; que la vente des offices de receveurs et payeurs des gages des officiers desdites chancelleries créez par édits... de novembre 1707 et décembre 1708 sera continuée ; et restablit les gardes des sceaux des chancelleries près les Cours dans leurs offices, en payant un supplément de finance... [Enregistré au Parlement le 13 juin 1716.]

[Acte royal. 1716-05-00. Paris]

Etat général des dettes de l'Etat à la mort du feu Roy Louis XIV . Arrivée le premier septembre 1715. Leur réduction & payement. Avec la suppression & extinction d'un grand nombre d'offices & droits, à la décharge des peuples, jusqu'au premier septembre 1720

[Acte. 1720]

Arrêt du conseil d'état portant suppression d'un livre imprimé sans permission

[Acte. 1752-06-28. Versailles]

(Arrêt du Grand Conseil qui ordonne la suppression d'un libelle intitulé : "Mémoire pour Messire Gui-Michel Billard de Lorière, conseiller au Grand Conseil, contre dame Marie-Henriette de Saint-Simon, son épouse.)

[Acte. 1755-08-30. Paris]