Posterior Part (posterior + part)

Distribution by Scientific Domains


Selected Abstracts


Buffalo Hump: Spindle Cell Lipoma in Posterior Part of the Neck

DERMATOLOGIC SURGERY, Issue 1 2007
DILEK SENEN MD
No abstract is available for this article. [source]


Analysis of Meox - 2 mutant mice reveals a novel postfusion-based cleft palate

DEVELOPMENTAL DYNAMICS, Issue 2 2006
Jiu-Zhen Jin
Abstract Cleft palate represents a common human congential disease involving defects in the development of the secondary palate. Major steps in mammalian palatogenesis include vertical growth, elevation, and fusion of the palate shelves. Our current study with the homeobox gene Meox - 2 during mouse secondary palate development reveals a novel postfusion-based mechanism for cleft palate. Meox - 1 and Meox - 2 are two functionally related homeobox genes playing important roles in somitogenesis and limb muscle differentiation. We found that the expression of Meox - 2, not Meox - 1, marks the specification of early mouse palatal mesenchymal cells in the maxillary processes at embryonic day 11.5 (E11.5). From E12.5 to E15.5, the expression of Meox - 2 occupies only the posterior part of the palate, providing an early molecular marker for the anterior,posterior polarity in mouse secondary palate formation. A total of 35.3% of Meox - 2,/, (n = 17) and 25.5% of Meox - 2+/, (n = 55) mouse embryos display a cleft palate phenotype at E15.5, indicating that the reduction of Meox - 2 function is associated with susceptibility to cleft palate. Unlike previously reported clefts, none of the clefts found in Meox - 2 mutants contain any epithelial sheets in the medial edge areas, and detailed examination revealed that the clefts resulted from the breakdown of newly fused palates. This article is the first report of a gene required to maintain adherence of the palatal shelves after fusion. Developmental Dynamics 235:539,546, 2006. © 2005 Wiley-Liss, Inc. [source]


Ultrastructural study of the jaw structures in two species of Ampharetidae (Annelida: Polychaeta)

ACTA ZOOLOGICA, Issue 3 2004
Alexander B. Tzetlin
Abstract Two species of jaw bearing Ampharetidae (Adercodon pleijeli (Mackie 1994) and Ampharete sp. B) were investigated in order to describe the microanatomy of the mouth parts and especially jaws of these enigmatic polychaetes. The animals of both studied species have 14,18 mouth tentacles that are about 30 µm in diameter each. In both species, the ventral pharyngeal organ is well developed and situated on the ventral side of the buccal cavity. It is composed of a ventral muscle bulb and investing muscles. The bulb consists of posterior and anterior parts separated by a deep median transversal groove. In both species, the triangular teeth or denticles are arranged in a single transversal row on the surface of the posterior part of the ventral bulb just in front of its posterior edge. There are 36 denticles in Adercodon pleijeli and 50 in Ampharete sp. B. The height of the denticles (6,12 µm) is similar in both species. Each tooth is composed of two main layers. The outer one (dental) is the electron-dense sclerotized layer that covers the tooth. The inner one consists of long microvilli with a collagen matrix between them. The thickness of the dental layer ranges from 0.95 to 0.6 µm. The jaws of the studied worms may play a certain role in scraping off microfouling. The fine structure of the jaws in Ampharetidae is very similar to that of the mandibles of Dorvilleidae, the mandibles and the maxillae of Lumbrineridae, Eunicidae and Onuphidae, and the jaws of other Aciculata. This type of jaw is characterized by unlimited growth and the absence of replacement. The occurrence of jaws in a few smaller Ampharetidae is considered as an apomorphic state. [source]


Fine structure of unusual spermatozoa and spermiogenesis of the mite Megisthanus floridanus Banks, 1904 (Acari: Gamasida: Antennophorina)

ACTA ZOOLOGICA, Issue 4 2002
Gerd Alberti
Abstract The aflagellate spermatozoa of the gamasid mite Megisthanus floridanus are characterized by a large vacuole which contains a cytoplasmic column protruding into the vacuole from the region defined as the posterior part of the cell. The membrane of the column and the inner membrane of the posterior part of the cytoplasmic mantle (outer sheath) surrounding the vacuole bear numerous so-called cellular processes. However, most of the outer sheath is reduced and represented solely by a very thin membrane-like envelope. The posterior part of the cell bears extensive folds. The cell, or, more precisely, the column, shows a deep posterior invagination. This invagination contains extracellular material composed of thin filaments or strands. Peripheral folds emerging from the posterior rim of the cell form a thin-walled tube that contains the same material as the invagination. The elongated nucleus is attached to a peculiar acrosomal complex consisting of a flat acrosomal cisterna that parallels most of the cell membrane, an attachment cone, and a short acrosomal filament which is embedded in a narrow canal within the nucleus. The spermatozoa of M. floridanus represent a peculiar version of the vacuolated type of sperm known to be plesiomorphic within the anactinotrichid Acari. Some details of spermiogenesis are described and consequences for phylogenetic and systematic considerations are discussed. [source]


Three-dimensional finite-element model of the human temporomandibular joint disc during prolonged clenching

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2006
Miho Hirose
In the temporomandibular joint (TMJ), overloading induced by prolonged clenching appears to be important in the cascade of events leading to disc displacement. In this study, the effect of disc displacement on joint stresses during prolonged clenching was studied. For this purpose, finite-element models of the TMJ, with and without disc displacement, were used. Muscle forces were used as a loading condition for stress analysis during a time-period of 10 min. The TMJ disc and connective tissue were characterized as a linear viscoelastic material. In the asymptomatic model, large stresses were found in the central and lateral part of the disc through clenching. In the retrodiscal tissue, stress relaxation occurred during the first 2 min of clenching. In the symptomatic model, large stresses were observed in the posterior part of the disc and in the retrodiscal tissue, and the stress level was kept constant through clenching. This indicates that during prolonged clenching the disc functions well in the asymptomatic joint, meanwhile the retrodiscal tissue in the symptomatic joint is subject to excessive stress. As this structure is less suitable for bearing large stresses, tissue damage may occur. In addition, storage of excessive strain energy might lead to breakage of the tissue. [source]


Receptor architecture of human cingulate cortex: Evaluation of the four-region neurobiological model

HUMAN BRAIN MAPPING, Issue 8 2009
Nicola Palomero-Gallagher
Abstract The structural and functional organization of the human cingulate cortex is an ongoing focus; however, human imaging studies continue to use the century-old Brodmann concept of a two region cingulate cortex. Recently, a four-region neurobiological model was proposed based on structural, circuitry, and functional imaging observations. It encompasses the anterior cingulate, midcingulate, posterior cingulate, and retrosplenial cortices (ACC, MCC, PCC, and RSC, respectively). For the first time, this study performs multireceptor autoradiography of 15 neurotransmitter receptor ligands and multivariate statistics on human whole brain postmortem samples covering the entire cingulate cortex. We evaluated the validity of Brodmann's duality concept and of the four-region model using a hierarchical clustering analysis of receptor binding according to the degree of similarity of each area's receptor architecture. We could not find support for Brodmann's dual cingulate concept, because the anterior part of his area 24 has significantly higher AMPA, kainate, GABAB, benzodiazepine, and M3 but lower NMDA and GABAA binding site densities than the posterior part. The hierarchical clustering analysis distinguished ACC, MCC, PCC, and RSC as independent regions. The ACC has highest AMPA, kainate, ,2, 5-HT1A, and D1 but lowest GABAA densities. The MCC has lowest AMPA, kainate, ,2, and D1 densities. Area 25 in ACC is similar in receptor-architecture to MCC, particularly the NMDA, GABAA, GABAB, and M2 receptors. The PCC and RSC differ in the higher M1 and ,1 but lower M3 densities of PCC. Thus, multireceptor autoradiography supports the four-region neurobiological model of the cingulate cortex. Hum Brain Mapp, 2009. © 2008 Wiley-Liss, Inc. [source]


Functional segregation of cortical language areas by sentence repetition

HUMAN BRAIN MAPPING, Issue 5 2006
Ghislaine Dehaene-Lambertz
Abstract The functional organization of the perisylvian language network was examined using a functional MRI (fMRI) adaptation paradigm with spoken sentences. In Experiment 1, a given sentence was presented every 14.4 s and repeated two, three, or four times in a row. The study of the temporal properties of the BOLD response revealed a temporal gradient along the dorsal,ventral and rostral,caudal directions: From Heschl's gyrus, where the fastest responses were recorded, responses became increasingly slower toward the posterior part of the superior temporal gyrus and toward the temporal poles and the left inferior frontal gyrus, where the slowest responses were observed. Repetition induced a decrease in amplitude and a speeding up of the BOLD response in the superior temporal sulcus (STS), while the most superior temporal regions were not affected. In Experiment 2, small blocks of six sentences were presented in which either the speaker voice or the linguistic content of the sentence, or both, were repeated. Data analyses revealed a clear asymmetry: While two clusters in the left superior temporal sulcus showed identical repetition suppression whether the sentences were produced by the same speaker or different speakers, the homologous right regions were sensitive to sentence repetition only when the speaker voice remained constant. Thus, hemispheric left regions encode linguistic content while homologous right regions encode more details about extralinguistic features like speaker voice. The results demonstrate the feasibility of using sentence-level adaptation to probe the functional organization of cortical language areas. Hum Brain Mapp, 2006. © 2006 Wiley-Liss, Inc. [source]


Optic radiation changes after optic neuritis detected by tractography-based group mapping

HUMAN BRAIN MAPPING, Issue 3 2005
Olga Ciccarelli
Abstract Postmortem data suggest that trans-synaptic degeneration occurs in the lateral geniculate nucleus after optic nerve injury. This study investigated in vivo the optic radiations in patients affected by optic neuritis using fast marching tractography (FMT), a diffusion magnetic resonance imaging (MRI) fiber tracking method, and group mapping techniques, which allow statistical comparisons between subjects. Seven patients, 1 year after isolated unilateral optic neuritis, and ten age and gender-matched controls underwent whole-brain diffusion tensor MR imaging. The FMT algorithm was used to generate voxel-scale connectivity (VSC) maps in the optic radiations in each subject in native space. Group maps of the left and right optic radiations were created in the patient and control group in a standardized reference frame using statistical parametric mapping (SPM99). The reconstructed optic radiations in the patient group were localized more laterally in the posterior part of the tracts and more inferiorly than in the control group. Patients showed reduced VSC values in both tracts compared with controls. These findings suggest that the group mapping techniques might be used to assess changes in the optic radiations in patients after an episode of optic neuritis. The changes we have observed may be secondary to the optic nerve damage. Hum Brain Mapp, 2005. © 2005 Wiley-Liss, Inc. [source]


Development of the pelvis and posterior part of the vertebral column in the Anura

JOURNAL OF ANATOMY, Issue 1 2005
Hana Ro, kovį
Abstract The anuran pelvic girdle is unique among all amphibians in that its acetabular portion is located far posterior to the sacrum, lateral to the postsacral (= caudal) vertebral column, which is reduced to a single rod-like element called the urostyle. This situation in the adult is strikingly different not only from that in ancestral temnospondyls but also in other modern amphibians. Because there is no fossil that would document this evolutionary anatomical modification except for Triadobatrachus, the only data may be inferred from development in modern anurans. We chose seven anuran species (belonging to the genera Discoglossus, Bombina, Pelobates, Bufo, Rana and Xenopus), representing the principal locomotory types (saltation, swimming, crawling and burrowing). Development of the pelvic girdle was studied on cleared and stained whole mounts and partly on serial histological sections. The basic developmental pattern was similar in all species: the pelvis on both sides develops from two centres (puboischiadic and iliac, respectively). The ilium then extends vertically towards the sacral vertebra and later rotates posteriorly so that ultimately the acetabulum is lateral to the tail (= urostyle). Only minor deviations from this pattern were found, mainly associated with differences in water and terrestrial dwelling. [source]


Typical Atrial Flutter Ablation: Conduction Across the Posterior Region of the Inferior Vena Cava Orifice May Mimic Unidirectional Isthmus Block

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2000
MARCO SCAGLIONE M.D.
Atrial Flutter Mapping. Introduction: The aim of this study was to map the low right atrium before and after radiofrequency ablation of the inferior vena cava-tricuspid annulus (IVC-TA) isthmus in patients with typical atrial flutter (AFI) to better understand the electrophysiologic meaning of incomplete or unidirectional block following the ablation procedure and its relationship with AFI recurrence. Methods and Results: We performed atrial mapping in 12 patients using a "basket" catheter in the IVC orifice, Halo catheter in the right atrium, and multipolar catheters in the coronary sinus (CS) and His region. In patients in sinus rhythm, atrial activation was analyzed during pacing from the CS and low lateral right atrium (KLRA) before and after ablation. Atrial activation propagated across the isthmus and posterior region of the IVC orifice simultaneously before ablation. Mapping during AFI in four patients showed that the crista terminalis was a site of functional block. After ablation, evaluation of Halo catheter recordings in three patients showed apparent unidirectional counterclockwise block, whereas analysis of basket catheter recordings demonstrated complete bidirectional block. The apparent conduction over the isthmus during pacing from proximal CS was due to conduction along the posterior part of the IVC orifice, which activated the LLRA despite complete isthmus block. Conclusion: Our results demonstrate that limited endocardial mapping may yield a pattern compatible with unidirectional block in the IVC-TA isthmus, although bidirectional block is present at this anatomic level. [source]


Morphology,diet relationships in four killifishes (Teleostei, Cyprinodontidae, Orestias) from Lake Titicaca

JOURNAL OF FISH BIOLOGY, Issue 3 2009
E. Maldonado
This study explores the relationship between morphology and diet in four Andean killifishes (Orestias) from Lake Titicaca that are known to differ in habitat use. Species that fed preferentially on amphipods (Orestias albus) or molluscs (Orestias luteus) separated in multivariate space from other species that feed on cladocera and algae (Orestias agassii and Orestias jussiei). Generally, specimens feeding on cladocera were characterized by a short, blunt nose with a small mouth; whereas, specimens feeding on amphipods exhibited a long snout with a large mouth. Specimens including molluscs in their diet tended to have a larger posterior part of the head and the larger opercles than others; while the occurrence of substratum in gut content was generally related to a short but deep head. The present analysis suggests that the littoral O. jussiei has an intermediate phenotype and diet between the pelagic (O. agassii) and benthic (O. albus and O. luteus) species. Results suggest that resource partitioning was occurring and that several morphological traits relate to characteristics of the diet, and it is inferred that the benthic, the pelagic and the littoral zones in the lake host different prey communities constituting distinct adaptive landscapes. [source]


Use of Stereolithographic Templates for Surgical and Prosthodontic Implant Planning and Placement.

JOURNAL OF PROSTHODONTICS, Issue 2 2006
Part II.
Eight implants were placed in the posterior part of the mandible using computer-generated stereolithographic templates. Preoperative implant simulation was done on a 3D computer model created by reformatted computerized tomography data. The surgeon and the prosthodontist positioned the simulated implants in the most favorable position addressing all concerns with regard to anatomy, biomechanics, and esthetics. The length and diameter of each implant along with the angulation/collar of abutments required for a screw-retained prosthesis were determined. Stereolithographic templates were then fabricated by incorporating the precise spatial position of the implants within the bone as previously planned during the computer simulation. The templates were fabricated to seat directly on the bone and were stable. The first template was used to complete osteotomies with a 2-mm twist drill followed by the second template for the 3-mm drill. Implants were placed and allowed to integrate for 4 months. After second-stage surgery, the definitive abutments were torqued into place followed by insertion of the definitive screw-retained prostheses. Dimensions of all implants and abutments were the same as planned during the computer simulation. [source]


Neuropathological analysis of an asymptomatic adult case with Dandy,Walker variant

NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 3 2006
G. Notaridis
The Dandy-Walker (DW) complex is a rare posterior fossa malformation, usually observed during the prenatal period or the early infancy. Clinically, it is characterized by mental retardation, seizures, cerebellar ataxia as well as symptoms of hydrocephalus. Structural imaging reveal a hypoplasia or agenesis of the cerebellar vermis, enlargement of the fourth ventricle with a posterior fossa cyst. Additional neurodevelopmental changes such as agenesis of the corpus callosum, lissencephaly and cortical dysplasia are also present. We report the first neuropathological analysis of an adult asymptomatic DW case. Brain computerized tomography showed a massive posterior fossa cyst and hypoplasia of the cerebellum. An Ehlers-Danlos syndrome type IV characterized by repetitive intestinal perforations and a saccular aneurysm on the left posterior communicating artery was also present. Macroscopic brain examination revealed hypoplasia of both cerebellar hemispheres and posterior part of the vermis, as well as dilatation of the fourth ventricle without hydrocephalus. The posterior fossa cyst wall was formed by an external arachnoid layer, middle layer with loose connective tissue and an internal layer of ependymal cells. There were two foci of cerebellar cortical dysplasia but no ectopic neurons, neuronal loss or gliosis in both cerebellum and cerebral cortex. No vascular or significant neurodegenerative lesions were observed. In comparison with previous reports in DW infants, this adult case displayed milder brain abnormalities compatible with a diagnosis of DW variant. The preservation of the cortical cytoarchitecture as well as the paucity of additional neurodevelopmental changes may explain the absence of clinical expression. [source]


The perception of speech sounds by the human brain as reflected by the mismatch negativity (MMN) and its magnetic equivalent (MMNm)

PSYCHOPHYSIOLOGY, Issue 1 2001
Risto Näätänen
The present article outlines the contribution of the mismatch negativity (MMN), and its magnetic equivalent MMNm, to our understanding of the perception of speech sounds in the human brain. MMN data indicate that each sound, both speech and nonspeech, develops its neural representation corresponding to the percept of this sound in the neurophysiological substrate of auditory sensory memory. The accuracy of this representation, determining the accuracy of the discrimination between different sounds, can be probed with MMN separately for any auditory feature (e.g., frequency or duration) or stimulus type such as phonemes. Furthermore, MMN data show that the perception of phonemes, and probably also of larger linguistic units (syllables and words), is based on language-specific phonetic traces developed in the posterior part of the left-hemisphere auditory cortex. These traces serve as recognition models for the corresponding speech sounds in listening to speech. MMN studies further suggest that these language-specific traces for the mother tongue develop during the first few months of life. Moreover, MMN can also index the development of such traces for a foreign language learned later in life. MMN data have also revealed the existence of such neuronal populations in the human brain that can encode acoustic invariances specific to each speech sound, which could explain correct speech perception irrespective of the acoustic variation between the different speakers and word context. [source]


Euplotespora binucleata n. gen., n. sp. (Protozoa: Microsporidia), a Parasite Infecting the Hypotrichous Ciliate Euplotes woodruffi, with Observations on Microsporidian Infections in Ciliophora

THE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 3 2008
SERGEI I. FOKIN
ABSTRACT. A new microsporidian species, Euplotespora binucleata n. gen., n. sp., from the brackish-water ciliate Euplotes woodruffi is described and defined on the basis of life history characteristics, light and electron microscopic features, and small subunit (SSU) ribosomal DNA (rDNA) sequencing. The life cycle of E. binucleata n. sp. probably has rather short merogonic and relatively long sporogonic phases. Some uninuclear meronts and sporonts, along with diplokaryotic sporoblasts and spores, were found in experimentally infected host cells. Such a peculiar life cycle has been induced experimentally in Euplotes eurystomus and constitutively microsporidian-free stocks of E. woodruffi. Spores of E. binucleata n. sp. are monomorphic, ovoid,cylindrical in shape, 3.44±0.17 × 1.65±0.22 ,m in size, and characterized by a diplokaryotic condition and a large posterior vacuole. The polar tube is isofilar, 4.5,5.5 ,m in length when ejected, and lacking a distinctive coiled region (half-coiled). The polaroplast is divided into two regions: the anterior part has a few lamellae close to the anchoring disc; and the posterior part is a rounded body (sack), about one-quarter of the spore length. Spores do not appear to cluster together as a group. Each spore is surrounded by a sporophorous membrane closely adjacent to the exospore layer. A phylogenetic analysis of SSU rDNA sequences by different methods placed E. binucleata n. sp. in a clade with representatives of the microsporidian genera Cystosporogenes and Vittaforma. Observations of microsporidia in several other ciliates are discussed in view of the microsporidian infection frequency in the phylum Ciliophora. [source]


Morphogenesis of the Marine Ciliate, Pseudoamphisiella alveolata (Kahl, 1932) Song & Warren, 2000 (Ciliophora, Stichotrichia, Urostylida) During Binary Fission

THE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 5 2006
CHEN SHAO
ABSTRACT. Morphogenesis during the binary fission of the stichotrich ciliate Pseudoamphisiella alveolata, isolated from Jiaozhou Bay near Qingdao, China, was investigated using protargol silver impregnation. The process is characterized as follows: (1) in the proter, only the posterior part of the parental adoral zone of membranelles is renewed, where the membranelles dedifferentiate and then rebuild the UM-anlage and the missing membranelles, (2) the oral primordium in the opisthe and the FVT-anlagen in both dividers are formed de novo on the cell surface, (3) an "extra" anlage, which is generated on the right of the right marginal anlage, develops into three or four "extra" marginal cirri that connect the caudal cirri with the marginal rows, (4) the right marginal anlage is formed within the old structure, (5) the FVT-cirri develop in a primary mode, and (6) unlike most stichotrichs, the right marginal anlagen in both dividers generate closely together. As an additional contribution, the diversity of morphogenetic patterns within the genus Pseudoamphisiella is discussed. Based on both morphogenetic and SS rRNA gene sequencing data, the systematic position of the genus Pseudoamphisiella as well as the family Pseudoamphisiellidae Song et al. 1997 is briefly analyzed. The results indicate that they should very possibly represent a higher evolved group in the order Urostylida. [source]


Scanning Electron Microscopic Study of the Lingual Papillae in the Arctic Fox (Alopex lagopus L., 1758)

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2009
H. Jackowiak
Summary This study aims to show the distribution and the three-dimensional structure of the lingual papillae in the arctic fox. The macro- and microscopic structure of the tongue and its lingual papillae was studied in 11 adult arctic foxes. Two types of mechanical papillae were distinguished on the dorsal surface of the tongue , filiform papillae and conical papillae. The gustatory papillae in the arctic fox are represented by fungiform, vallate and foliate papillae. The keratinized filiform papillae on the anterior part of tongue are composed of one big posterior process accompanied by 10,12 secondary anterior processes. The number of anterior processes of filiform papillae undergo a complete reduction within the area between the posterior part of the body of the tongue and area of the vallate papillae. The conical papillae cover the whole dorsal surface of the root of the tongue, including the lateral parts surrounding the area of the vallate papillae and the posterior part of the root. The size of the conical papillae increases towards the root of the tongue but their density decreases. In the arctic fox, there are three pairs of vallate papillae distributed on the plan of a triangle. The diameter of vallate papillae in each successive pair is bigger. The wall surrounding the body of the vallate papilla and its gustatory trench is composed of six to eight conical papillae joined at various degree. The foliate papillae on both margins of the tongue consist of seven to nine laminae. [source]


Textural properties of raw Atlantic salmon (Salmo salar) fillets measured by different methods in comparison to expressible moisture

AQUACULTURE NUTRITION, Issue 2 2001
Jonsson
Textural properties of fresh Atlantic salmon (Salmo salar) fillets were measured on seven locations along the fillet by four different instrumental methods, and were correlated to expressible moisture. Two methods were based on puncturing, either by using a flat ended cylinder, measuring hardness at different distances into the fillet and the first fracture (yield point) of the muscle fibres, or by a non-destructive method using a spherical probe to measure the hardness of the fillet. The other two methods were based on Kramer shear-compression cell or Warner-Bratzler shear cell, by shearing the fillet with blades, measuring the shear force (toughness). The ability to separate textural properties in different muscle segments by using these four methods were compared. The expressible moisture, was determined by using the filter paper method by compression. Hardness and shear force of the fillets generally increased from the anterior to the posterior part of the fillet while the necessary force applied to map the yield point decreased towards the tail section. The results from the present study indicated that the puncture method with the spherical probe and the shearing device by Warner-Bratzler were better suited for measuring differences in the textural properties between different parts of raw salmon fillet, than the flat ended cylinder and Kramer shear compression cell. The expressible moisture, varying between 1.8 and 2.7%, showed a significant (P < 0.05) linear correlation with the spherical probe texture measurements (r=0.83) and the Kramer shear compression cell (r=0.77). [source]


Malignant changes in a giant orbital keratoacanthoma developing over 25 years

ACTA OPHTHALMOLOGICA, Issue 2 2000
Ghassan A. Alyahya
ABSTRACT. Purpose: To report a patient with a history over 25 years of a slowly growing, large, invasive crateriform tumour filling the anterior part of the orbit. Methods: A 61-year-old male presented with a large tumour of the left orbit. Exenteration was performed with subsequent histological analysis of the excised mass. Results: The main tumour showed the characteristic features of a keratoacanthoma. However, the posterior aspect of the tumour disclosed the morphology of a squamous cell carcinoma. Six months later, the patient presented with metastases to lymph nodes, lung and mediastinal tissue. A leukemoid reaction was diagnosed by fine needle biopsy. Conclusion: The giant variety of keratoacanthoma may fail to regress and can transform into a squamous cell carcinoma. In our patient, the development of a chronic lymphoid leukemia raises the possibility that it may be the underlying cause for the transformation of the posterior part of the keratoacanthoma into a frank squamous cell carcinoma. [source]


Lung fractional moving blood volume in normally grown and growth restricted foetuses

CLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 2 2004
Edgar Hernandez-Andrade
Summary Objective:, To examine foetal lung blood perfusion using power Doppler ultrasound (PDU) and to compare fractional moving blood volume (FMBV) and mean pixel intensity (MPI) estimations in the lungs of normally grown (NG) foetuses and foetuses with intrauterine growth restriction (IUGR) and also to correlate foetal lung FMBV and MPI with respiratory complications after birth. Methods:, Lungs of 47 NG and 25 IUGR foetuses after 32 weeks of gestation were examined with PDU. FMBV and MPI were estimated in a defined region in the posterior part of the foetal lung closest to maternal abdominal wall. FMBV and MPI were correlated to foetal weight deviation and gestational age. Perinatal outcome and respiratory complications after birth were recorded in both groups. Results:, There were significantly lower FMBV and MPI values in IUGR than in NG foetuses. The overall variation was lower for FMBV than for MPI. There was a slightly higher correlation between FMBV and foetal weight deviation [r = 0·33, 95% confidence intervals (CI) 0·11,0·52] than between MPI and foetal weight deviation (r = 0·26, 95% CI 0·03,0·46). There was no significant correlation between FMBV or MPI and gestational age. No differences between the groups were found in the rate of respiratory complications, and they were not correlated either to the FMBV or MPI. Conclusion:, FMBV and MPI, estimated from the PDU signals of foetal lung circulation, showed lower values in third-trimester pregnancies complicated by IUGR. The frequency of neonatal respiratory complications was not increased in cases with low pulmonary FMBV and MPI values. [source]


Ultrasound control for presumed difficult epidural puncture

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2001
T. Grau
Background: The efficacy of epidural anaesthesia depends on the accurate identification of the epidural space (ES). Abnormal anatomical conditions may make the procedure difficult or impossible. The aim of this study was to investigate whether pre-puncture ultrasound examination of the spinal anatomy might be beneficial in expected cases of difficult epidural anaesthesia. Methods: We used digital ultrasound equipment with a 5-MHz transducer to assess the anatomy of the ES and the posterior parts of the spinal column. We examined 72 parturients with abnormal anatomical conditions who were scheduled for epidural anaesthesia. The women were randomised into two equal groups. In all patients, the standard loss of resistance technique was used. In the ultrasound group, an ultrasound examination of the appropriate spinal region was conducted prior to epidural puncture. ES depth seen on the ultrasound images was compared to the ES depth measured by the needle. We compared the number of puncture attempts with the standard method (control group) to the number of attempts under ultrasound guidance. Results: Ultrasonography significantly improved operating conditions for epidural anaesthesia. The maximum VAS scores and patient acceptance were significantly better. Conclusions: With ultrasound measurement of the ES depth, the quality of epidural anaesthesia was enhanced. [source]


Scanning Electron Microscopical Study of the Lingual Epithelium of Green Iguana (Iguana iguana)

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2008
F. Abbate
Summary During the last few years, green iguanas (Iguana iguana) have turned out to be one of the most popular pets. They are omnivorous. In their way of feeding, this crucial function is performed by capturing of the preys and mostly, this is carried out by the tongue. The role of the tongue is also fundamental during the intra-oral transport and during the swallowing of food. This has been reported in several studies about chameleons, agamids and iguanids, nevertheless published data about the mechanisms of capturing and swallowing the prey, and the morphological descriptions about the tongue epithelium, are scarce. Therefore, the aim of this present study was to analyse the morphology of the lingual epithelium in green iguanas by scanning electron microscopy. Three different areas were demonstrated on the tongue surface: the tongue tip, characterized by a smooth epithelium without papillae, a foretongue, completely covered by numerous closely packed cylindriform papillae, and a hindtongue with conical-like papillae. Some taste buds were recognized on the middle and the posterior parts of the tongue. Different functional roles could be hypothesized for the three tongue areas: the tongue tip could have a role related to the movements of the prey immediately after the capturing, while the middle papillae and the hindtongue could have an important role concerning the swallowing phase. [source]


Anatomy and physiology of the human eye: effects of mucopolysaccharidoses disease on structure and function , a review

CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 2010
Colin E Willoughby MD
Abstract The current paper provides an overview of current knowledge on the structure and function of the eye. It describes in depth the different parts of the eye that are involved in the ocular manifestations seen in the mucopolysaccharidoses (MPS). The MPS are a group of rare inheritable lysosomal storage disorders characterized by the accumulation of glycosaminoglycans (GAGs) in cells and tissues all over the body, leading to widespread tissue and organ dysfunction. GAGs also tend to accumulate in several tissues of the eye, leading to various ocular manifestations affecting both the anterior (cornea, conjunctiva) and the posterior parts (retina, sclera, optic nerve) of the eye. [source]