Adipose tissue and cholesterol metabolism

Adipose tissue in man is a major site for cholesterol storage. In obesity over half of total body cholesterol may reside within this tissue; however, relatively little attention has been directed toward understanding the cholesterol metabolism and its relationship to whole body cholesterol homeostasis in this tissue. In this review the factors which influence cholesterol storage are discussed, with particular emphasis on the effects of diet and drug treatment in both animals and man. The uptake, synthesis, and mobilization of adipose tissue cholesterol appears to be mediated and/or regulated, as in other tissues, by the plasma lipoproteins, and these processes are examined with regard to both normal and pathologic states.     

Development and rudimentation of the peripheral olfactory system in the harbor porpoise Phocoena phocoena (Mammalia: Cetacea)

Serial sections of 13 embryos and fetuses of the harbor porpoise from 10 mm crown-rump length up to 167 mm total length were studied. Unlike the adult animals, ontogenetic stages of 18–27 mm crown-rump length still show a typical mammalian olfactory bulb. The olfactory bulb primordium is penetrated by olfactory nerve fibers, the latter passing through the cribriform plate. However, the olfactory bulb anlage is gradually reduced in later stages, its placodal component being largely uncoupled from the telencephalon. As a ganglionlike structure, the remains of the placodal component stay in contact with the nasal septum and mucosa via thin bundles of nerve fibers. The ganglion and plexus can be traced within the meninges until the adult stage of the porpoise. There is strong evidence that they represent the material of the terminalis system, which cannot be distinguished from the olfactory system in earlier stages. A vomeronasal organ could not be detected in the embryonal and fetal material investigated.     

Spatial and temporal pattern of light-regulated gene expression during tobacco seedling development: the photosystem II-related genes Lhcb (Cab) and PsbP (Oee2)

The white mustard ( Sinapis alba L.) Lhcb1*1 and PsbP*1 genes that code for proteins related to photosystem II (PSII) in chloroplasts were examined by analysis of promoter fragment β-glucuronidase (GUS) reporter constructs in transgenic tobacco ( Nicotiana tabacum L.) seedlings. The endogenous tobacco genes and the introduced mustard genes follow the same kinetics during seedling development and they show the same expression characteristics for light regulation and for the influence of a 'plastidic signal'. Hence, the cellular environment of the host plant always dominates the regulation of Lhcb1*1 and PsbP*1 gene expression; as with the mustard system clear differences in the temporal pattern and the physiological responses could be seen. The spatio-temporal pattern of gene expression was analysed in the different organs of the transgenic tobacco seedlings. In the cotyledons, expression at the PsbP*1 promoter starts in advance, and both genes show a rather uniform distribution of expression during seedling development. In the hypocotyl, a sequential basipetal pattern could be detected and a coordinated expression for the two promoters was analysed. The hypocotyl base is only included in this expression pattern if the seedlings receive light at early stages of development, whereas in later stages gene expression is repressed. A model is proposed that divides tobacco seedling development into three main phases.     

Investigations of the butylcholinesterase-containing cells of the adenohypophysis of the white-crowned sparrow,Zonotrichia leucophrys gambelii

Summary In the adenohypophysis of Zonotrichia leucophrys gambelii two types of cells with butylcholinesterase(BuChE) activity can be demonstrated histochemically. Type I occurs in the cephalic lobe of the pars distalis and in the pars tuberalis; it consists of oval and round cells. It is a distinctive cell type that is identical with the amphophilic cells described by Matsuo, Vitums, King and Farner (1969). Whereas castration or inhibition of thyroid gland activity causes only minor changes in these cells, blocking of adrenal cortex activity, or adrenalectomy, causes conspicuous hyperplasia and hypertrophy suggesting that these cells are involved in the production or release of ACTH. The second type, which occurs in both cephalic and caudal lobes, consists mostly of irregularly formed cells. Various observations indicate that it is a composite group, consisting, at least in part, of degenerating cells.These investigations were supported by grants from the National Institutes of Health (S ROI NB 06812) and the National Science Foundation (GB 5969) to Professor Farner.     

Morphological and histochemical features of the duodenal glands in six marsupial species

The duodenal glands of four marsupial species, the kangaroo, native cat, marsupial mouse, and bandicoot, form a narrow lobular collar immediately distal to the gastrointestinal junction. In two species, the koala and wombat, the duodenal glands are diffuse and scattered along the intestinal tract distal to the gastrointestinal junction for considerable distances. The glands of all species examined empty independently into the intestinal lumen. Histochemical studies indicate that the latter two species, the koala and wombat, elaborate an acid mucin whereas the former species produce a neutral mucosubstance. Ultrastructural examination shows that generally the duodenal glands are comprised of large pyramidal cells that show a definite polarity, with basally-placed nuclei and apically-situated secretory granules. Species differences, with regard both to the morphology and nature of the secretory granules and to the proportions of cell organelles, exist. The diversity of diet between species is discussed.     

Words matter: Reflections on language projects with chimpanzees and their implications

Beginning in the 1960s the first systematic projects dedicated to testing whether great apes could acquire some aspects of human language were conducted. The ape subjects demonstrated remarkable capacities to learn and use elements of either sign language or an artificial language. The results from research across several laboratories drew a mixture of excitement and skepticism, and critiques and debates have ensued since the earliest reports were published. This continues today. Terrace (2019, Nim: A chimpanzee who learned sign language. New York, NY: Columbia University Press) repeats many of the same points made decades earlier, and has added some additional critiques. That scientists hold different perspectives on what to conclude from ape language studies is expected. However, any conclusion one draws should be based upon available evidence, which we outline in this review. We also address the critiques offered by Terrace (2019), including the stance that apes cannot understand or use words. Focusing on symbol use by chimpanzees and bonobos we describe evidence that argues for understanding of words, including capacities for declarative communication and intersubjectivity found in these apes. We conclude that the many decades of research using a variety of symbol systems challenges the absolutist position that chimpanzees and bonobos cannot learn language or understand the concept of a word.