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Investigated Species (investigated + species)
Selected AbstractsThe circulatory system in Chilopoda: functional morphology and phylogenetic aspectsACTA ZOOLOGICA, Issue 3 2002Christian S. Wirkner Abstract The circulatory organs of nine representative species of all five chilopod orders were examined by light microscopy and by in vivo observations of haemolymph flow. In Scutigera coleoptrata, the heart ultrastructure was studied. The circulatory system in Craterostigmomorpha is described for the first time. Further focus is placed on the Geophilomorpha since previous descriptions in this group have been only superficial. In all investigated species, the circulatory system consists of two longitudinal central vessels which are connected in the first body segment by the maxilliped arch. The posterior part of these vessels is contractile and thus haemolymph is pumped anteriorly in the heart, while it is pumped posteriorly in the supraneural vessel. From these central vessels numerous peripheral vessels branch off. Differences among the chilopod orders lie mainly in the distribution of the peripheral vessels. The circulatory system in Scutigeromorpha shows some striking morphological adaptations with regard to the functional coupling of circulatory and respiratory tasks. The most peculiar structures are the aortic diverticles which act as accessory pumps in the head. Phylogenetic analysis of the circulatory organ traits within Chilopoda supports the Pleurostigmophora hypothesis. Synapomorphies supporting the Myriapoda hypothesis or the Tracheata concept were not found. [source] Periodontal infection profiles in type 1 diabetesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2006Evanthia Lalla Abstract Objectives: We investigated the levels of subgingival plaque bacteria and serum IgG responses in patients with type 1 diabetes and non-diabetic controls of comparable periodontal status. Material and Methods: Fifty type 1 diabetes patients (mean duration 20.3 years, range 6,41) were age-and gender-matched with 50 non-diabetic individuals with similar levels of periodontal disease. Full-mouth clinical periodontal status was recorded, and eight plaque samples/person were collected and analysed by checkerboard hybridization with respect to 12 species. Homologous serum IgG titres were assessed by checkerboard immunoblotting. In a sub-sample of pairs, serum cytokines and selected markers of cardiovascular risk were assessed using multiplex technology. Results: Among the investigated species, only levels of Eubacterium nodatum were found to be higher in diabetic patients, while none of the IgG titres differed between the groups, both before and after adjustments for microbial load. Patients with diabetes had significantly higher serum levels of soluble E-selectin (p=0.04), vascular cell adhesion molecule-1 (VCAM-1; p=0.0008), adiponectin (p=0.01) and lower levels of plasminogen activator inhibitor-1 (PAI-1; p=0.02). Conclusions: After controlling for the severity of periodontal disease, patients with type 1 diabetes and non-diabetic controls showed comparable subgingival infection patterns and serum antibody responses. [source] Functional genital morphology of armored spiders (Arachnida: Araneae: Tetrablemmidae)JOURNAL OF MORPHOLOGY, Issue 9 2008Matthias BurgerArticle first published online: 18 JUN 200 Abstract This study describes the female genitalia of the tetrablemmid spiders Brignoliella acuminata, Monoblemma muchmorei, Caraimatta sbordonii, Tetrablemma magister, and Ablemma unicornis by means of serial semi-thin sections and scanning electron microscopy and compares the results with previous findings on Indicoblemma lannaianum. Furthermore, the male palps and chelicerae are briefly described. The general vulval organization of females is complex and shows similarities in all of the investigated species. The copulatory orifice is situated near the posterior margin of the pulmonary plate. The opening of the uterus externus lies between the pulmonary and the postgenital plate. Paired copulatory ducts lead to sac-like receptacula. Except for A. unicornis, the male emboli of all investigated species are elongated and thread-like. However, they are too short to reach the receptacula. Hence, the spermatozoa have to be deposited inside the copulatory ducts. The same situation was also found in I. lannaianum. Females of this species store sperm encapsulated in secretory balls in their receptacula. The secretion is produced by glands adjoining the receptacula. The presence of paired fertilization ducts and spermatozoa in the uterus internus suggested that fertilization takes place internally in I. lannaianum. Secretory balls in the receptacula are found in all of the investigated species in this study, showing that sperm are stored in the same way. The place of fertilization may also be identical since dark particles, presumably spermatozoa, are located in the uterus internus of all investigated species except for T. magister. However, fertilization ducts are only found in B. acuminata and M. muchmorei. A sclerotized central process with attached muscles is present in A. unicornis, M. muchmorei, C. sbordonii and T. magister. Only in A. unicornis does the central process show an internal lumen and hold spermatozoa. In the other species, it could be used to lock the uterus during copulation in order to prevent sperm from getting into it as suggested for certain oonopid species. The uterus externus of all investigated species shows a sclerotized dorsal fold with attached muscles, previously described as "inner vulval plate." Contractions of the muscles lead to a widening of the dorsal fold, thus creating enough space for the large oocytes to pass the narrow uterus externus. The males of all investigated species have apophyses on their chelicerae. At least in B. acuminata and A. unicornis, where females have paired grooves on the preanal plate, these apophyses allow males to grasp the female during copulation as described for I. lannaianum. © 2008 Wiley-Liss, Inc. [source] SEASONAL VARIABILITY OF THE ORGANIC-WALLED DINOFLAGELLATE CYST PRODUCTION IN THE COASTAL UPWELLING REGION OFF CAPE BLANC (MAURITANIA): A FIVE-YEAR SURVEY,JOURNAL OF PHYCOLOGY, Issue 1 2010Karin A. F. Zonneveld A 5-year sediment trap survey in the upwelling area off Cape Blanc (NW Africa) provides information on the seasonal and annual resting cyst production of dinoflagellates, their sinking characteristics and preservation potential. Strong annual variation in cyst production characterizes the region. Cyst production of generally all investigated species, including Alexandrium pseudogonyaulax (Biecheler) T. Horig. ex T. Kita et Fukuyo (cyst genus Impagidinium) and Gonyaulax spinifera (Clap. et J. Lachm.) Diesing (cyst genus Nematosphaeropsis) was enhanced with increasing upper water nutrient and trace-element concentrations. Cyst production of Lingulodinium polyedrum (F. Stein) J. D. Dodge was the highest at the transition between upwelling and upwelling-relaxation. Cyst production of Protoperidinium americanum (Gran et Braarud) Balech, Protoperidinium monospinum (Paulsen) K. A. F. Zonn. et B. Dale, and Protoperidinium stellatum (D. Wall) Balech, and heterotrophic dinoflagellates forming Brigantedinium spp. and Echinidinium aculeatum Zonn., increased most pronouncedly during upwelling episodes. Production of Protoperidinium conicum (Gran) Balech and Protoperidinium pentagonum (Gran) Balech cysts and total diatom valves were related, providing evidence of a predator,prey relationship. The export cyst-flux of E. aculeatum, P. americanum, P. monospinum, and P. stellatum was strongly linked to the flux of total diatom valves and CaCO3, whereas the export production of Echinidinium granulatum Zonn. and Protoperidinium subinerme (Paulsen) A. R. Loebl. correlated with total organic carbon, suggesting potential consumption of diatoms, prymnesiophytes, and organic matter, respectively. Sinking velocities were at least 274 m · d,1, which is in range of the diatom- and coccolith-based phytoplankton aggregates and "slower" fecal pellets. Species-selective degradation did not occur in the water column, but on the ocean floor. [source] Sexual differences and effect of photoperiod on melatonin receptor in avian brainMICROSCOPY RESEARCH AND TECHNIQUE, Issue 1 2001Nicoletta Aste Abstract Several data suggest that melatonin may influence avian reproduction by acting at the level of the hypothalamic-hypophisial-gonadal axis, and/or on neural circuits controlling reproductive behaviours. The action of melatonin is exerted through specific receptors whose distribution and pharmacological properties have been extensively investigated. This review will focus on the distribution, sexual dimorphism, and dependence upon the photoperiod of melatonin binding sites in avian species with a special emphasis on Japanese quail. Melatonin receptors are widely distributed in avian brain. They are mostly present in the visual pathways of all the investigated species and in the song controlling nuclei of oscine birds. Sexual dimorphism of melatonin binding sites (higher density in males than in females) was detected in some telencephalic nuclei of songbirds, in the visual pathways, and in the preoptic area of quail. The last region plays a key role in the activation of male quail copulatory behaviour and it hosts a large population of gonadotropin-releasing hormone-containing neurons. Sexual dimorphism of melatonin-binding sites in the above-mentioned regions suggests a differential role for this hormone in the modulation of visual perception, gonadotropin production, and seasonally activated behaviours in male and female quail. Further studies are necessary to understand interrelationships among photic cues, gonadal steroids, density, and sexually dimorphic distribution of melatonin receptors. Microsc. Res. Tech. 55:37,47, 2001. © 2001 Wiley-Liss, Inc. [source] Systematics of Chaetocerotaceae (Bacillariophyceae).PHYCOLOGICAL RESEARCH, Issue 2 2003SUMMARY In order to construct a model of evolutionary relationships within the diatom family Chaetocerotaceae, 37 species of Chaetoceros Ehrenberg, representing all subgenera and 21 of 22 subgeneric sections of the genus, plus three Bacteriastrum Shadbolt species, representing both of its subgeneric sections, were subjected to cladistic analysis. One species each of Eucampia Ehrenberg, Cerataulina Peragallo, Hemiau-lus Ehrenberg, Attheya West and Gonioceros H. & M. Peragallo were used as outgroups. A matrix of 65 binary and multistate morphological characters was constructed, with data being gathered from original observation of material in the light and electron microscopes, and from the published literature. The analysis yielded 36 most-parsimonious cladograms of 316 steps; incongruence between trees is largely restricted to some taxa representing undersampled sections of Chaetoceros subg. Hyalochaete. The robustness of this hypothesis was examined in several ways. To assess the effect of character weighting, the bootstrap was used to randomly weight characters. The parsimony criterion was relaxed via a decay index, and finally, the tree length was compared to that of trees randomly generated from the data matrix. The majority of investigated species of Chaetoceros subg. Phaeoceros, Chaetoceros subg. Hyalochaete and Bacteriastrum appear to belong to a continuous grade, rather than comprising individual clades. Chaetoceros is paraphyletic. Thus, the traditional classification does not accurately reflect the hypothesized phylogenetic relationships of this family. [source] Functional water-soluble polymers: polymer,metal ion removal and biocide propertiesPOLYMER INTERNATIONAL, Issue 10 2009Bernabé L Rivas Abstract Water-soluble polymers have attracted much interest due to their potential applications in environmental protection engineering to remove harmful pollutants and in biomedicine in the areas of tissue engineering, within-body implants or other medical devices, artificial organ prostheses, ophthalmology, dentistry, bone repair, and so on. In this review, particular emphasis is given to the ability of water-soluble polymers with amine, amide, carboxylic acid, hydroxyl and sulfonic acid functional groups to remove metal ions by means of the liquid-phase polymer-based retention (LPR) technique that combines the use of water-soluble polymers and ultrafiltration membranes. The second part is dedicated to showing the potential application of functional water-soluble polymers and their polymer,metal complexes as biocides for various bacteria. These polymers and polymer,metal complexes show an efficient bactericide activity, especially to Gram-negative bacteria, Staphylococcus aureus reaching concentrations lower than 4 µg mL,1. This activity depends on polymer size, type of metal ion, contact time and concentration of polymer and metal ion. The discussion reveals that in the case of the LPR process the efficiency of metal ion removal depends strongly on the type of polymer functional group and the feed pH value. In general, two mechanisms of ion entrapment are suggested: complex formation and electrostatic interaction. In the case of the medical use of water-soluble polymers and their complexes with metal ions, the review documents the unique bactericide properties of the investigated species. The polymer-metal ion complexes show a reduced genotoxic activity compared with free metal ions. Copyright © 2009 Society of Chemical Industry [source] | |||||||||||||