Home About us Contact
|
Home About us Contact | ||
|
|
||
Morphological Investigation (morphological + investigation)
Selected AbstractsMorphological Investigation of Carotid Body and Its Arteries in RabbitsANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2002E. Unur Summary The purpose of this study was to determine the morphology of the rabbit carotid body and its artery at the light microscopy level. The carotid body was situated between the internal and external carotid arteries after the bifurcation point of the common carotid artery. The carotid body was usually found to be a single, ovoid tissue mass but, in some cases it consisted of two or three parts. More carotid bodies were supplied by a single carotid body artery (glomic artery) which arose from the common carotid artery or the internal or external carotid arteries near the bifurcation point of the common carotid artery. In only one case were there two arteries which arose from opposite sides of the external carotid artery at its origin. There was a distinguishable sinus (glomic sinus) at the origin of the glomic artery. This artery had a thin wall with elastic laminae in the sinus area which become thinner distal to the sinus. [source] Morphological Investigations on the Circulus Arteriosus Cerebri in Mole-Rats (Spalax leucodon)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2008A. Aydin Summary The aim of the present study is to investigate the circulus arteriosus cerebri in mole-rats (Spalax leucodon). Six adult mole-rats were used for this purpose. Coloured latex was injected into the left ventriculus of the hearts of all the animals. After careful dissection, the circulus arteriosus cerebri (the circle of Willis) was investigated. The cerebrum and the cerebellum were supplied by the internal carotid- and the basilar arteries respectively forming the circulus arteriosus cerebri in mole-rats. In the investigated objects, the internal carotid- and the basilar arteries were not united directly and for this reason the circulus arteriosus cerebri was not formed completely in mole-rat. The branches supplying the medulla oblongata and the cerebellum originate from the basilar artery formed by union of the left and right vertebral arteries and the internal ophthalmic, the caudal cerebral, the choroid, the median cerebral, the rostral cerebral arteries originated from the internal carotid artery. After giving off the medial cerebral artery, the right and left rostral cerebral arteries on every two sides divided into the lateral and medial twin branches and by union of the lateral branches the internal ethmoidal artery, and by union of the medial branches, the ramus extending to facies medialis cerebri were formed. The ramus extending to the facies medialis cerebri was anastomosed with the branch of the caudal cerebral artery on the back of the corpus callosum. The last part of the basilar artery gave the two branches running toward the right and left side on the pontocrural groove (sulcus pontocruralis) and every one of these branches ramified into two rami. One of these rami formed into the rostral cerebellar artery and the other one extended to the tectum mesencephali. In conclusion, the arterial circle of the cerebrum and cerebellum was supplied by the internal carotid artery and the basilar artery respectively in mole-rats. [source] Evaluation of the Effectiveness of New Compatibilizers Based on EBAGMA-LDPE and EBAGMA-PET Masterbatches for LDPE/PET BlendsMACROMOLECULAR MATERIALS & ENGINEERING, Issue 3 2010Aida Benhamida Abstract The present paper is aimed to evaluate the efficiency of two masterbatches, i.e., EBAGMA/LDPE (MB1) and EBAGMA/PET (MB2) with 50/50 w/w composition, prepared by melt mixing and used as new compatibilizers for blends of LDPE/PET. The morphology, the mechanical and the thermal properties of LDPE/PET/MB1 and LDPE/PET/MB2 ternary blends have been investigated. Morphological investigation by SEM of LDPE/PET/MB1 ternary blends showed a finer dispersion of PET in LDPE matrix with a better interfacial adhesion compared to those of both LDPE/PET/MB2 and binary LDPE/PET blends. The results also indicated a substantial improvement in both elongation at break and impact strength, while the Young's modulus decreased. Moreover, the thermal properties showed a decrease of the crystallization phenomena of PET in LDPE/PET/MB1 blend, thus confirming the good dispersion of PET particles into the continuous phase of LDPE matrix, leading to the conclusion that MB1 could be an efficient compatibilizer for LDPE/PET system. [source] Synthesis and characterization of polyurethane/polybenzoxazine-based interpenetrating polymer networks (IPNs)POLYMER INTERNATIONAL, Issue 8 2003Yanjun Cui Abstract Sequential interpenetrating polymer networks (IPNs), based on polyurethane and polybenzoxazine, were synthesized. Fourier Transform infrared spectrometry was employed to monitor the formation kinetics, which indicated that only physical bonding existed in the resulting IPNs. Morphological investigations revealed a lightly phase separation behaviour in all of the IPNs studied. © 2003 Society of Chemical Industry [source] Unlubricated Wear Behavior of Ce-TZP/ Al2O3 Nanocomposites Against Bearing Steel,ADVANCED ENGINEERING MATERIALS, Issue 3 2005G. Yang Unlubricated friction and wear tests of Ce-TZP/Al2O3 nanocomposites against bearing steel were performed. In order to elucidate the wear mecahnism, the morphological investigation and phase structural analysis of worn surfaces were carried out by X-ray diffractometer and scanning electron microscope. Additionally, three kinds of wear mechanisms such as plastic deformation, adhesive wear and brittle fracture have been revealed. [source] A palynological study of Galium L. (Rubiaceae) in Egypt and its systematic implicationFEDDES REPERTORIUM, Issue 7-8 2007K. Abdel Khalik A pollen morphological investigation of eleven species and one subspecies of the genus Galium L. from Egypt were undertaken by using light microscope (LM) and scanning electron microscope (SEM). Pollen shape, size, exine ornamentation, number of apertures present powerful characters for distinguishing between species. The pollen grains were zonocolpate. The number of colpi ranges from 5 to 10. Their shape varies from prolate spheroidal, oblate spheroidal, spheroidal to suboblate. Three groups can be distinguished based on the size pollen grains. It was found used to distinguish between closely related species G. aparine and G. spurium and between G. tricornutum and G. ceratopodum. Two different types of exine ornamentation were recognized. The ornamentation was found useful to distinguish among closely related species such as Galium aparine and G. spurium. A key for the identification of the investigated taxa based on pollen grains characters is provided. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Eine palynologische Studie der Gattung Galium L. (Rubiaceae) in Ägypten und ihre Bedeutung für die Systematik Die Pollenmorphologie von elf Arten und einer Unterart der Gattung Galium L. aus Ägypten wurde mittels Licht- und Elektronenmikroskopie untersucht. Pollenform, Größe und Muster der Exine und die Anzahl der Aperturen repräsentieren gute Merkmale zur Unterscheidung der betrachteten Arten. Alle Pollen sind zonocolpat. Die Anzahl der Colpi liegt zwischen 5 bis 10. Ihre äußere Form variiert von prolat über sphäroidal, oblat-sphäroidal, sphäroidal bis suboblat. Auf Grund der Pollengröße lassen sich drei Gruppen unterscheiden. Es zeigte sich, dass diese drei Gruppen genutzt werden können, um die eng verwandten Arten Galium aparine und G. spurium sowie G.tricornatum und G. ceratopodum von einander zu trennen. Zwei Typen der Exine-Muster ließen sich erkennen. Sie sind geeignet um z. B. so eng verwandte Arten wie Galium aparine und G. spurium zu trennen. Ein Schlüssel, der geeignet ist, die untersuchten Taxa auf der Basis ihrer Pollenmerkmale zu bestimmen beschließt die Arbeit. [source] Anatomy and ultrastructure of the reproductive organs in Dactylopodola typhle (Gastrotricha: Macrodasyida) and their possible functions in sperm transferINVERTEBRATE BIOLOGY, Issue 1 2008Alexander Kieneke Abstract. The reproductive anatomy of gastrotrichs is well known for several species, especially for the marine taxon Macrodasyida. However, there is little information on the reproductive organs and the modes of mating and sperm transfer in putative basal taxa, which is necessary for accurate reconstruction of the ground pattern of the Gastrotricha. We present the first detailed morphological investigation of the reproductive system of a putative basal gastrotrich, Dactylopodola typhle, using transmission and scanning electron microscopy, histology, and microscopic observations of living specimens. Dactylopodola typhle is a hermaphrodite that possesses paired female and male gonads, an unpaired uterus with an outlet channel that we call the cervix, and an additional accessory reproductive organ, the so-called caudal organ. We hypothesize that the hollow, secretory caudal organ serves for picking up autospermatozoa (self-sperm), for spermatophore formation, and finally for transferring the autospermatophore to a mating partner. The allospermatophore (foreign spermatophore) is stored within the uterus where fertilization occurs. We think that the mature and fertilized egg is released through the cervix and the dorsolateral female gonopore, and not by rupture of the body wall. Based on the morphology, we provide a plausible hypothesis for spermatophore formation and transfer in D. typhle. Preliminary phylogenetic considerations indicate that the stem species of Macrodasyida, perhaps that of all Gastrotricha, had paired ovaries and paired testes, an unpaired uterus, and only one accessory reproductive organ. [source] Evolutionary and comparative anatomical investigations of the autonomic cardiac nervous system in the African cercopithecidaeJOURNAL OF MORPHOLOGY, Issue 9 2007Tomokazu Kawashima Abstract The purpose of this study was to clarify the general architecture and morphological variations of the autonomic cardiac nervous system (ACNS) in the African Cercopithecidae (Old World monkeys), and to discuss the evolutionary changes between this system in African/Asian Cercopithecidae and humans. A detailed macroscopic comparative morphological investigation of the ACNS was performed by examining the left and right sides of 11 African cercopithecid specimens, including some previously unreported species (Abyssinian colobus, Angola pied colobus, Savanna monkey, and lesser white-nosed guenon). The common characteristics of the ACNS in the African Cercopithecidae are described in detail. Consequently, homologies of the ACNS between Asian (macaques) and African Cercopithecidae, and differences between the Asian/African Cercopithecidae and humans, were found. In particular, differences in the sympathetic (cardiac) systems of the Cercopithecidae and humans were recognized, despite the similar morphology of the parasympathetic vagal (cardiac) system. These differences include the composition of the cervicothoracic ganglion, the lower positions of the middle cervical and cervicothoracic ganglia, and the narrow range for the origin of the cardiac nerves in the Cercopithecidae, compared with that in humans. In conclusion, these findings are considered with regard to the morphology of the last common ancestors of the Cercopithecidae. J. Morphol., 2007 © 2007 Wiley-Liss, Inc. [source] Vascular amyloid of unknown origin and senile transthyretin amyloid in the lung and gastrointestinal tract of old age: Histological and immunohistochemical studiesPATHOLOGY INTERNATIONAL, Issue 5 2001Hironobu Matsutani The histological and immunohistochemical characteristics and the incidence of amyloid deposits in the tissues of the lung and gastrointestinal tract were investigated in 64 autopsied individuals who were 80 years and older (age range: 80,92 years; mean: 83.3 years). Immunohistochemical examination was performed with antibodies against amyloid A, transthyretin, immunoglobulin , and , light chain amyloid fibril proteins, ,2 -microglobulin, , protein, apolipoprotein AI, apolipoprotein AII, atrial natriuretic peptide, apolipoprotein E, and amyloid P component. Transthyretin amyloid fibril protein (ATTR) deposits were observed in five cases (7.8%). Gastrointestinal amyloid deposits of unknown origin were observed in the veins of the gastrointestinal tract in 26 cases (40.6%). This amyloid was regarded as portal amyloid with respect to distribution pattern. Pulmonary vascular amyloid deposits of unknown origin were observed in 12 cases (18.8%). These amyloid deposits were found mainly in medium-sized veins in the lungs and did not react with any antibodies against amyloid fibril proteins except apolipoprotein E and amyloid P component. Eleven of the 26 cases (42.3%) showing portal amyloid also showed pulmonary vascular amyloid of unknown origin. The pulmonary vascular amyloid deposits were similar to the portal amyloid deposits with respect to their morphological features and their relation to elastic fibers in the vessels. Further morphological investigation and biochemical analysis of the pulmonary vascular amyloid and portal amyloid will resolve questions of their origins and relation. [source] Hominid Mandibular Remains from Sangiran: 1952,1986 CollectionAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2005Yousuke Kaifu Abstract Eight hominid mandibular and associated dental remains discovered between 1952,1986 from the Early Pleistocene deposits of Sangiran, Central Java, are described. Although the specimens are surface finds, their original stratigraphic positions can be reasonably inferred on the basis of coincidental sources of information. These specimens significantly increase the dento-gnathic sample available for intensive morphological investigation of the earliest Javanese hominids [Kaifu et al., 2005]. Am J Phys Anthropol, 2005. © 2005 Wiley-Liss, Inc. [source] On the Structure of the Adrenal Gland of the Common Seal (Phoca vitulina vitulina)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2004H. Bragulla Summary The adrenal gland is a vitally important endocrine gland that occupies a central role in the regulatory mechanisms of the body metabolism. Environmental stress factors lead to permanent strain and overload of the body resulting in structural alterations of the adrenals that in turn are followed by hormonal imbalances. This leads to an increased susceptibility to bacterial and viral diseases. The recurrence of numerous fatalities in the different seal populations of the North Sea (during the years 1988, 1989 and 2002), of the Baikal Lake and Caspian Sea (during the years 2000 and 2001) were the motive for a morphological investigation of the species-specific structure of the adrenal gland of the common seal in order to differentiate environmental stress-induced pathological alterations from the physiological structure of this organ. The study was based on adrenals of 112 common seals (Phoca vitulina vitulina) using light microscopic and transmission and scanning electron microscopic methods. The phocine adrenal gland displays several structural characteristics. Originating from the connective tissue organ capsule, narrow and broad septa intersperse the adrenal cortex. These septa contain blastemata as a reserve for the regeneration of hormone-producing cortical cells. Such blastemata are also occurring in the form of an intermediate zone in between the zona glomerulosa and zona fasciculata in the phocine adrenal cortex. Another species-specific characteristic is an inverse part of the adrenal cortex encircling the central vein of the organ. These structural features have to be considered in assessment and definition of pathological alterations of the adrenals as observed in the form of exhausted blastema cell pools in the adrenocortex of seals perished in the mentioned phocine mass mortalities. [source] Initiating electropolymerization on graphene sheets in graphite oxide structureJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2010Ali Eftekhari Abstract Because of its special chemical composition, graphite oxide has peculiar influences on electrochemical processes. The existence of various functional groups significantly affects electropolymerization processes and the formation of conductive polymers. Electrochemical synthesis of polyaniline (as a prototype of conductive polymers) on a paste-based substrate of graphite oxide was investigated. In this case, the electropolymerization is significantly different from conventional cases, and the polymer is generated just during the first potential cycle. This can be attributed to the fact that graphite oxide can assist the monomer oxidation. Alternatively, electropolymerization was successfully performed inside the graphite oxide layers via electrochemical treatment of aniline-intercalated graphite oxide in the supporting electrolyte. Although these phenomena are related to the chemical composition of graphite oxide, the graphite prepared by the reduction of graphite oxide also displayed some advantages for the electropolymerization (over natural graphite). There is an emphasis on the morphological investigations throughout this study, because novel morphologies were observed in the system under investigation. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2204,2213, 2010 [source] Host plant adaptations in myrtaceous-feeding Pergid sawflies: essential oils and the morphology and behaviour of Pergagrapta larvae (Hymenoptera, Symphyta, Pergidae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2000S. SCHMIDT Australian pergine sawflies typically feed on eucalypts and other closely-related Myrtaceae, which are known for their high content of essential oils. We describe a novel morphological adaptation of the inner mandibular surface of larval stage Pergagrapta species, which feed on leaves of Melaleuca quinquenervia (Myrtaceae). This ,scopa mandibularis' forms an extensive mesh of setaceous papillae on what is usually the grinding surface of the mandible. Behavioural, chemical and morphological investigations of the sawfly- Melaleuca system suggest that the scopa may function in the physical separation of toxic leaf oils from the diet. The oils are stored in a pharyngeal diverticulum from where they are ejected under two circumstances. Oil from the diverticulum is voided prior to feeding and/or during feeding at night, which indicates a mechanism to eliminate host-associated oils. Larvae rest in close aggregations during the day, when they retain a full diverticulum, but the oils may be emitted for defensive purposes when larvae are disturbed. Chemical evidence suggests that 1,8-cineole, the major component in the M. quinquenervia leaves, is selectively metabolized to a more soluble hydroxycineole. We postulate that the separation and regurgitation of oils is not only a defence mechanism against predators, as usually stated, but also a mechanism by which pergid larvae eliminate oils from their diet, to reduce the toxicity of their food plants. [source] Modulation of cell adhesion and viability of cultured murine bone marrow cells by arsenobetaine, a major organic arsenic compound in marine animalsBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2001Teruaki Sakurai In this study, we investigated the biological effects of trimethyl (carboxymethyl) arsonium zwitterion, namely arsenobetaine (AsBe), which is a major organic arsenic compound in marine animals using murine bone marrow (BM) cells and compared them with those of an inorganic arsenical, sodium arsenite, in vitro. Sodium arsenite showed strong cytotoxicity in BM cells, and its IC50 was 6 ,M. In contrast, AsBe significantly enhanced the viability of BM cells in a dose-dependent manner during a 72-h incubation; about a twofold increase in the viability of cells compared with that of control cells cultured with the medium alone was observed with a ,M level of AsBe. In morphological investigations, AsBe enhanced the numbers of large mature adherent cells, especially granulocytes, during a 72-h BM culture. When BM cells were cultured together with AsBe and a low dose (1 u ml,1) of recombinant murine granulocyte/macrophage colony-stimulating factor (rMu GM-CSF), significant additive-like increasing effects were observed on the numbers of both granulocytes and macrophages originated from BM cells. However, AsBe did not cause proliferation of BM cells at all as determined by colony-forming assay using a gelatious medium. These findings demonstrate the unique and potent biological effects in mammalian cells of AsBe, a major organic arsenic compound in various marine animals which are ingested daily as seafood in many countries. British Journal of Pharmacology (2001) 132, 143,150; doi:10.1038/sj.bjp.0703790 [source] | ||||||||||||||||