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1.
We aimed to examine the effects of KTO-7924 (beta3-adrenoceptor agonist) on lipid metabolism and mRNA expressions in retroperitoneal white adipose tissue (RP WAT) in obese (fa/fa) Zucker rats using DNA microarray. Oral KTO-7924 for 28 days significantly decreased RP WAT weight, plasma triglyceride, free fatty acid, and insulin, and improved insulin resistance in oral glucose tolerance tests. In RP WAT of KTO-7924-treated rats, DNA microarray analysis revealed specifically enhanced mRNA expressions of uncoupling protein 1 (UCP1) and cytochrome c oxidase subunit VIII-H (COX8H), which are reportedly highly expressed in brown adipose tissue (BAT). Since these mRNA expression levels in RP WAT were significantly lower in obese (fa/fa) Zucker rats than in lean Zucker rats, these genes may be important in lipid metabolism. Our results imply that in obese (fa/fa) Zucker rats, continuous stimulation of beta3-adrenoceptors by KTO-7924 causes BAT-like adipocytes to appear in RP WAT, and improves lipid metabolism.  相似文献   
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Bone morphogenetic proteins (BMPs) play important roles in early lung development. No study to date has addressed a role for BMP signaling in late lung development. We describe changes in the expression and localization of BMP receptors (Bmpr1a, Bmpr1b, and Bmpr2) and Smad (Smad1, Smad4, Smad5, and Smad8) intracellular signaling proteins during the saccular and alveolarization stages of late lung development. BMP signaling, assessed by Smad1/5 phosphorylation, nuclear translocation, and induction of id1, id2, and id3 gene expression, was evident throughout late lung development. Our data indicate that BMP signaling is active during late lung development, and points to roles for the BMP system in septal and vascular development, and in the homeostasis of the epithelial layer of large conducting airways in the mature lung.  相似文献   
3.
Pseudomonas aeruginosa causes a chronic infection in the lungs of cystic fibrosis (CF) patients by establishing an alginate-containing biofilm. The infection has been studied in several animal models; however, most of the models required artificial embedding of the bacteria. We present here a new pulmonary mouse model without artificial embedding. The model is based on a stable mucoid CF sputum isolate (NH57388A) with hyperproduction of alginate due to a deletion in mucA and functional N-acylhomoserine lactone (AHL)-based quorum-sensing systems. Chronic lung infection could be established in both CF mice (Cftr(tmlUnc-/-)) and BALB/c mice, as reflected by the detection of a high number of P. aeruginosa organisms in the lung homogenates at 7 days postinfection and alginate biofilms, surrounded by polymorphonuclear leukocytes in the alveoli. In comparison, both an AHL-producing nonmucoid revertant (NH57388C) from the mucoid isolate (NH57388A) and a nonmucoid isolate (NH57388B) deficient in AHL were almost cleared from the lungs of the mice. This model, in which P. aeruginosa is protected against the defense system of the lung by alginate, is similar to the clinical situation. Therefore, the mouse model provides an improved method for evaluating the interaction between mucoid P. aeruginosa, the host, and antibacterial therapy.  相似文献   
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Summary Two arterial systems contribute to the blood supply of the penis. The deeper system, responsible for supplying the erectile tissues, arises from the internal pudendal arteries (a. pudendae internae), or sometimes from an accessory internal artery. Four branches, either collateral or terminal, should be considered: the artery to the bulb of the penis, the urethral artery, the deep artery of the penis and the dorsal artery of the penis. Variations are frequently present in the origin, distribution and symmetry of these arteries, but on the whole the blood supply is organised into three planes, inferior or ventral, middle and deep, superior or dorsal. These three planes are complementary: when the blood supply to any one of them is occluded, at whatever level this may be, the blood supply is supplemented by the plane immediately above it. Arteriograms should be interpreted with caution because anatomical variations may at first sight be taken for pathological change.The superficial system, supplying the tissues around the erectile organs, arises from the lateral inferior pudendal arteries. Three types of supply have been described, according to whether the right and left arteries have a symmetrical distribution or whether the arterial network arises in large part or totally from one side.
Contribution à l'étude de la vascularisation artérielle du pénis
Résumé Deux systèmes artériels participent à la vascularisation du pénis. Le système profond, tenant sous sa dépendance les organes érectiles, a pour origine les artères honteuses internes (a. pudendae internae), parfois une artère interne accessoire. Quatre branches, collatérales ou terminales sont à considérer: l'artère du bulbe du pénis, l'artère urètrale, l'artère profonde du pénis, l'artère dorsale. Il existe de fréquentes variations dans l'origine, la distribution et la symétrie de ces artères mais, dans son ensemble, la vascularisation est organisée selon trois plans, inférieur ou ventral, moyen ou profond, supérieur ou dorsal. Ces trois plans sont complémentaires: lorsque l'un d'eux s'épuise, à quelque niveau que ce soit, le relais est pris par le plan immédiatement supérieur.Le système superficiel, vascularisant les enveloppes provient des artères honteuses externes inférieures. Trois types de vascularisation sont décrits, selon que les deux artères droite et gauche ont une distribution symétrique ou que le réseau artériel provient en majeure partie ou totalement d'un seul côté.
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Summary The dissection of 100 external jugular veins in 50 cadavers was the object of this anatomic study. A certain number of notions concerning the afferent veins, the mode of termination and the valvular system of this vessel were defined. 1)Afferent veins. Along its pathway toward the deep venous system, the external jugular vein successively received: the transverse cervical vein in 88 cases (88%), usually opposite the intersection of the external jugular vein with the dorsal border of the sterno- cleidomastoid muscle; the suprascapular vein in 47 cases (47%); the anterior jugular vein in 46 cases (46%); the cervical vein or anastomosis with the latter in 13 cases (13%). 2)Mode of termination. Forty-three subjects presented a symmetric mechanism. 100 anastomoses can be classed into three types: in 60 cases (60%), the external jugular vein flowed into the jugulo-subclavian venous confluence; in 36 cases (36%), in to the subclavian vein at a distance from its junction with the internal jugular vein; in 4 cases (4%) in to the trunk of the internal jugular vein. 3)Study of the valves. There were studied in 25 subjects (50 external jugular veins). The valves were found in the ostial and paraostial position in 49 out of 50 veins.
Contribution à l'étude des afférences et de la terminaison de la veine jugulaire externe
Résumé Cette étude anatomique repose sur la dissection de 100 vv. jugulaires externes chez 50 cadavres. Elle a permis de préciser un certain nombre de notions concernant les veines afférentes, le mode de terminaison et le système valvulaire de ce vaisseau. 1)Veines afférentes. Le long de son trajet vers le sytème veineux profond, la v. jugulaire externe reçoit successivement: la v. cervicale transverse dans 88 cas (88 %), habituellement en regard du croisement de la v. jugulaire externe avec le bord dorsal du m. sterno-cléido-mastoïdien ; la v. supra-scapulaire dans 47 cas (47 %); la v. jugulaire antérieure dans 46 cas (46 %) ; la v. céphalique ou une anastomose avec celle-ci dans 13 cas (13 %). 2)Mode de terminaison. Quarante trois sujets présentent un dispositif symétrique. Les 100 abouchements peuvent être classés en trois types : dans 60 cas (60 %) la v. jugulaire externe se déverse dans le confluent veineux jugulo-subclavier ; dans 36 cas (36 %), dans la v. subclavière à distance de sa réunion avec la v. jugulaire interne ; dans 4 cas (4 %) dans le tronc de la v. jugulaire interne. 3)Etude des valvules. Recherchées chez 25 sujets (50 vv. jugulaires externes), les valvules ont été retrouvées dans 49 cas sur 50 en position ostiale ou paraostiale.
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Bovine nodular thelitis is a granulomatous dermatitis associated with infection with acid-fast bacteria. To identify the mycobacterium responsible for this infection, we conducted phylogenetic investigations based on partial sequencing of 6 genes. These bacteria were identified as an undescribed Mycobacterium species that was phylogenetically related to M. leprae and M. lepromatosis.  相似文献   
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