Fluorometric, Chromatographic, and Spectronic Evidence for the Non-indolic Nature of Citrus Auxin

Evidence for the non-indolic nature of the new citrus auxinis presented on the basis of fluorometric properties, thin-layerchromatography, Ehrlich's colour reaction, paper electrophoresis,and the infra-red spectra determinations. Citrus auxin had alower Rf in TLC than IAA, did not give the typical indole reactionwith Ehrlich's reagent, and behaved differently in electrophoresis.The infra-red spectra also provided preliminary informationconcerning chemical structure. The hypothesis that indolic compoundsconstitute the only natural auxins in higher plants should berevised in view of this evidence that a non-indole auxin existsin higher plants.     

The Avian Shoulder: An Experimental Approach

SYNOPSIS. This essay is in two parts. The first describes functionalstudies of the shoulder in modern vertebrates that led to theformulation of the hypotheses that motor patterns of homologousmuscles have been maintained during the evolution of the tetrapodshoulder, and that a primitive organization of the neural controlcomponents has persisted in derived groups. The second part of this essay focuses upon a longstanding questionin vertebrate evolution: what neuromuscular and musculoskeletalchanges in the tetrapod shoulder accompanied the evolution offlight in birds? The lack of empirical data on shoulder functionin extant birds limited our insight into this question, andprompted our initiation of experimental studies. Preliminarykinematics of the furcula and humerus of European starlings(Sturnus vulgaris) flying in a wind tunnel, as revealed by highspeed cineradiography, are presented. The two halves of thefurcula, which contact the coracoids dorsally, are bent laterallyduring downstroke and medially during upstroke by as much as60% of the intrafurcular resting distance. High speed film andelectromyographic studies of freeflying pigeons (Columba livia)reveal that the supracoracoideus muscle is strongly activatedduring wing elevation and, as predicted from studies of Varanusand Didelphis, an additional activation burst occurs at mid-downstrokein 48% of the recordings.     

Historical and Ecological Factors in the Biogeography of Aposematic Neotropical Butterflies

SYNOPSIS. Quantitative analysis of low-level (mostly subspecific)geographic differentiation of aposematic color patterns in threegroups of forest butterflies (Heliconiini, Ithomiinae, and Troidini),in 1,550 half-degree quadrants throughout the Neotropics, indicatesfour principal species-endemicity regions, 44 principal subspecies-endemicitycenters, and 300 quadrants of subspecies hybridization. Theendemism centers are different in outline but nearly identicalin position for each of the three ecologically different groups.Basic data on present and past physical environments (climate,soils, geomorphology, and vegetation structures), when integratedinto maps, show 1) regions of favorable ecological conditionsfor forest organisms in the present, 2) regions of environmentalconformities and rapid transitions in the present, and 3) regionsof high probability for humid forest persistence during themajor landscape changes at the end of the last glacial period,13,000–20,000 yr ago. Species diversity (a local phenomenon)is readily related to favorable modern ecological conditionsand environmental microheterogeneity, promoted by unpredictablemild disturbance. Biogeographical patterns of evolution at thelevel of regional subspecies correlate very well with presumedpaleoecological conditions. The biogeographical data also supportan hypothesis of differentiation resulting from areas of rapidenvironmental change; most of the hybridization quadrants fallwithin transition zones. There is lower correlation betweencenters of endemism and zones of en vironmental conformity,but some individual cases of differentiation in the butterfliesmay be adequately explained by modern ecological factors. Speciespresently undergoing differentiation in isolated habitat islands(Amazonian savannas and high-altitude Andean forests and paramos)may offer the best opportunities for observation of evolutionaryprocesses in the present.     

Cloning and characterization of a novel gene encoding keratin-like protein from nematode Nippostrongylus brasiliensis.

Nippostrongylus brasiliensis (Nb) is one of the most important parasites in studying Th2 immune response of the host, but little is known about its antigenic structures of the excretory-secretory or structural proteins of the parasite. Here we report cloning and characterization of a novel antigenic gene from cDNA library of Nb adult worm by immunoscreening. The positive clone, KLP-Nb, had an open reading frame of 612 bp that encodes a 203-amino-acid protein and was homologous to 'similar to keratins in a glycine-rich region' of Caenorhabditis elegans. Its expression was confirmed by Northern blotting and IgG enzyme-linked immunosorbent assay. This protein seems to be one of the components of cuticle that covers the nematode body.     

Phylogeny of the Altingiaceae based on cpDNA matK, PY-IGS and nrDNA ITS sequences

 Phylogenetic relationships of the three genera of the family Altingiaceae, i.e., Altingia, Liquidambar and Semiliquidambar, based on matK sequences and the intergenic spacer between the psaA and ycf3 genes (PY-IGS) of cpDNA, and on the internal transcribed spacer (ITS) of nrDNA were studied. Phylogenetic trees based on the three data sets (matK, PY-IGS and ITS) were generated using Hamamelis japonica and Mytilaria laosensis (Hamamelidaceae), Cercidiphyllum japonicum (Cercidiphyllaceae), and Daphniphyllum calycinum (Daphniphyllaceae) as outgroups. The partition-homogeneity tests indicated that the three data sets and the combined data are homogeneous. A combined analysis also generated a strongly supported phylogeny. The phylogenetic trees show that the North American and western Asian species, L. styraciflua and L. orientalis, respectively, form a monophyletic group which is sister to the clade including all Asian species in the family. The genus Liquidambar is paraphyletic with Altingia and Semiliquidambar nested within. Phylogenetic analyses of the molecular data indicate that taxonomic reexamination of the generic delimitation in the Altingiaceae is needed. Received December 20, 2000 Accepted June 25, 2001     

Occupancy of Mountain Plover and Burrowing Owl in Colorado

Abstract: Concern over the decline of grassland birds has spurred efforts to increase understanding of grassland bird-habitat relationships. Previous studies have suggested that black-tailed prairie dogs (Cynomys ludovicianus) provide important habitat for shortgrass prairie avifauna, such as mountain plover (Charadrius montanus) and western burrowing owl (Athene cunicularia hypugaea), although such studies are lacking in Colorado (USA). We used methods to estimate occupancy (ψ) of mountain plover and burrowing owl on prairie dog colonies and other shortgrass prairie habitats in eastern Colorado. Mountain plover occupancy was higher on prairie dog colonies (ψ = 0.50, 95% CI = 0.36–0.64) than on grassland (ψ = 0.07, 95% CI = 0.03–0.15) and dryland agriculture (ψ = 0.13, 95% CI = 0.07–0.23). Burrowing owl occupancy was higher on active prairie dog colonies (ψ = 0.80, 95% CI = 0.66–0.89) compared with inactive colonies (ψ = 0.23, 95% CI = 0.07–0.53), which in turn was much higher than on grassland (ψ = 0.01, 95% CI = 0.00–0.07) and dryland agriculture (ψ = 0.00, 95% CI ψ 0.00–0.00). Mountain plover occupancy also was positively correlated with increasing amounts of prairie dog colony in the landscape. Burrowing owl occupancy was negatively correlated with increasing amounts of prairie dog colony in the surrounding landscape. Our results suggest that actions to conserve mountain plovers and burrowing owls should incorporate land management to benefit prairie dogs. Because managing for specific colony attributes is difficult, alternative management that promotes heterogeneity may ensure that suitable habitat is available for the guild of grassland inhabitants.     

Differential regulation of three thyroid hormone-responsive matrix metalloproteinase genes implicates distinct functions during frog embryogenesis.

Matrix metalloproteinases (MMPs) are a family of Zn(2+)-dependent extracellular proteases capable of degrading various proteinaceous components of the extracellular matrix (ECM). They are expressed in developmental and pathological processes such as postlactation mammary gland involution and tumor metastasis. Relatively few studies have been carried out to investigate the function of MMPs during embryogenesis and postembryonic organ development. Using Xenopus development as a model system, we and others have previously isolated three MMP genes as thyroid hormone response genes. They have distinct temporal and organ-specific regulations during thyroid hormone-dependent metamorphosis. We demonstrate here that three MMPs-stromelysin-3 (ST3), collagenases-3 (Col3), and collagenases-4 (Col4)-also have distinct spatial and temporal expression profiles during embryogenesis. Consistent with earlier suggestions that ST3 is a direct thyroid hormone response gene whereas Col3 and Col4 are not, we show that precocious overexpression of thyroid hormone receptors in the presence of thyroid hormone lead to increased expression of ST3, but not Col3. Furthermore, our whole-mount in situ hybridizations reveal a tight but distinct association of individual MMPs with tissue remodeling in different regions of the animal during embryogenesis. These results suggest that ST3 is likely to play a role in ECM remodeling that facilitate apoptotic tissue remodeling or resorption, whereas Col3 and Col4 appear to participate in connective tissue degradation during development.     

Initial Characterization of Micafungin Pulmonary Delivery via Two Different Nebulizers and Multivariate Data Analysis of Aerosol Mass Distribution Profiles

Pharmaceutical aerosols have been targeted to the lungs for the treatment of asthma and pulmonary infectious diseases successfully. Micafungin (Astellas Pharma US, Deerfield, IL, USA) has been shown to be an effective antifungal agent when administrated intravenously. Pulmonary delivery of micafungin has not previously been reported. In the present pilot study, we characterize the performance of two nebulizers and their potential for delivering micafungin to the lungs as well as the use of multivariate data analysis for mass distribution profile comparison. The concentration of micafungin sodium increased by 21% when delivered by the Acorn II nebulizer and by 20% when delivered by the LC Plus nebulizer, respectively, from the first to the second sampling period. The Acorn II nebulizer delivered a fine particle fraction FPF_5.8 (%<5.8 μm) of 92.5 ± 0.8 and FPF_3.3 (%<3.3 μm) of 82.3 ± 2.1 during the first sampling period. For the LC Plus nebulizer, FPF_5.8 was 92.3 ± 0.1 and FPF_3.3 was 67.0 ± 0.7 during the first sampling period. The mass median aerodynamic diameter (MMAD) increased from 1.67 ± 0.05 to 1.77 ± 0.04 μm (Acorn II nebulizer) and from 2.09 ± 0.01 to 2.20 ± 0.01 μm (Pari LC Plus nebulizer) from the first to the second sampling periods. These changes in MMAD were statistically significant by paired t test. Multivariate data analysis showed that this could be explained systematically by greater drug deposition on stages with larger cutoff sizes and reduced drug deposition on stages with smaller cutoff sizes rather than multimodal deposition or other anomalies in size distribution.