Morphological Features (morphological + feature)

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Morphological Features

  • characteristic morphological feature


  • Selected Abstracts


    Morphological Features of the Stomach of Malayan Pangolin, Manis javanica

    ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2010
    C. Nisa'
    With 6 figures Summary The morphology of the stomach of Malayan pangolin, Manis javanica was studied at macroscopic, light microscopic, and scanning electron microscopic levels. The stomach of M. javanica was C-shaped with short lesser curvature. At the oesophageal junction, the inner smooth muscle was thickened in the greater curvature side. The entire stomach was lined by a thick cornified stratified squamous epithelium, except at the duct orifices of glands and in the pyloric gland region. The wall of the fundus was thin and devoid of glands. The gastric glands consisted of mucous, oxyntic, and pyloric glands. The mucous glands were observed in the lesser curvature (Mg-L), in the greater curvature (Mg-G), and in the pyloric canal (Mg-C) respectively. The oxyntic glands were organized into gland mass, making an oval mound elevated to the gastric lumen, in the middle of the greater curvature. The oxyntic gland mass has a single common duct with opening directed to the pyloric side. This duct was surrounded by mucus gland (Mg-G). The pyloric glands were located caudal to the pylorus. There was no sphincter at the pyloric-duodenal junction. Large mucosal protuberance, the torus pyloricus was observed in the side of the lesser curvature of the pyloric canal. In the lumen of pyloric canal region, numerous spines and small pebbles were observed. The muscle layers in the wall of this region were considerably thickened. The present results on the stomach of M. javanica are thought to be closely related to the toothless and eating habits of this animal species. [source]


    Poly(styrene- co -glycerol dimethacrylate): Synthesis, characterization, and application as a resin for gel-phase peptide synthesis

    JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 19 2005
    Michael Roice
    Abstract An efficient cross-linked polymer support for solid-phase synthesis was prepared by introducing glycerol dimethacrylate cross-linker to polystyrene network using free radical aqueous suspension polymerization. The support was characterized by various spectroscopic methods. Morphological feature of the resin was analyzed by microscopy. The polymerization reaction was investigated with respect to the effect of amount of cross-linking agent, which in turn vary the swelling, loading, and the mechanical stability of the resin. The solvent uptake of the polymer was studied in relation to cross-linking and compared with Merrifield resin. The stability of the resin was tested in different synthetic conditions used for solid-phase peptide synthesis. Hydroxy group of the support was derivatized to chloro and then amino groups using different reagents and reaction conditions. Efficiency of the support was tested and compared with TentaGelÔ resin by following different steps involved in the synthesis of the 65,74 fragment of acyl carrier protein. The results showed that the poly(styrene- co -glycerol dimethacrylate) (GDMA-PS) is equally efficient as TentaGel resin in peptide synthesis. The purity of the peptides was analyzed by HPLC and identities were determined by mass spectroscopy and amino acid analysis. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4382,4392, 2005 [source]


    Morphological features of Murray Valley encephalitis virus infection in the central nervous system of swiss mice

    INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 1 2000
    Vance Matthews
    We have examined the histological and ultrastructural features of CNS infection with Murray Valley encephalitis (MVE) virus in mice inoculated with a virulent parental strain (BH3479). Light microscopic examination revealed neuronal necrosis in the olfactory bulb and hippocampus of MVE-infected brains by 5 days post-infection (pi). Electron microscopy of these regions showed endoplasmic reticulum membrane proliferation, and tubular and spherical structures in the cisternae of the endoplasmic reticulum, Golgi complex and nuclear envelope. At seven to eight days pi, infected neurones exhibited chromatin condensation and extrusion, nuclear fragmentation, loss of segments of the nuclear envelope, reduced surface contact with adjacent cells and loss of cytoplasmic organelles. This cell injury was particularly noticeable in the proximal CA3 and distal CA1 regions of the hippocampus. The inflammatory cell profile consisted of macrophages, lymphocytes and especially neutrophils, and many of these inflammatory cells were apoptotic. High mortality rates in the BH3479-infected population of mice correlated with the intense polymorphonuclear and mononuclear leucocyte inflammatory infiltrate in the CNS. [source]


    Determination of twin-screw extruder operational conditions for the preparation of thermoplastic vulcanizates on the basis of batch-mixer results

    JOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008
    F. Goharpey
    Abstract In this study, we attempted to prepare a thermoplastic vulcanizate in a twin-screw extruder by determining the screw configuration on the basis of batch-mixer results. In this regard, two sets of information were used: (1) the time length, power consumption, and filling factor of different stages of the reactive blending process in the internal mixer and (2) the mean residence time and power consumption of the twin-screw extruder. Morphological features of the samples taken from the melt-mixing and dynamic vulcanization zones of the extruder with the selected screw configuration were found to be comparable with corresponding samples taken from an internal mixer reported in our previous study. The rheological and mechanical properties could provide valuable information to support the reliability of this study. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]


    Observations of Dermocystidium sp. infections in bullheads, Cottus gobio L., from a river in southern England

    JOURNAL OF FISH DISEASES, Issue 4 2004
    S W Feist
    Abstract Bullheads, Cottus gobio, with macroscopic external cysts on the skin and fins measuring up to 3 mm in diameter were detected in the River Allen and its tributaries in southern England between 1992 and 1998. The prevalence of these cysts was up to 50% at some sites. Examination of cyst contents revealed the presence of numerous spores, typical of the genus Dermocystidium, measuring 8 ,m in diameter. The parasite developed within well-defined cysts, which were located in the hypodermal connective tissues of the host. No cysts were present on the fins of any of the fish examined. Histological examination revealed a cyst wall consisting of an inner layer of dense eosinophilic material similar to that reported for Dermocystidium spp. forming coenocytic hyphae. No evidence was found of systemic infection or hyphal formation. Spores contained a prominent refractile body, which gave a weakly positive reaction for polysaccharides with the periodic-acid Schiff reaction and was positively stained with acidic dyes. Several examples of ruptured cysts were seen in histological sections and in some of these cases the host epithelial layer was breached, allowing release of the spores to the environment. Morphological features of, and host response towards, the Dermocystidium sp. in bullheads are compared with similar infections in salmonids and other freshwater fish species. [source]


    Morphological features and clinical feasibility of thoracic duct: Detection with nonenhanced magnetic resonance imaging at 3.0 T

    JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2010
    Yu De-xin MD
    Abstract Purpose: To evaluate the detection of the thoracic duct using nonenhanced magnetic resonance imaging (MRI) and to determine the influence of some related disorders on the lymphatic duct. Materials and Methods: Highly fluid-sensitive sequence and fat-suppressed T2-weighted imaging (FS-T2WI) were performed in a total of 139 cases. The axial and coronal images were used to locate the thoracic duct and the measurement and evaluation of its dimensions were performed using a 3D maximum intensity projection (MIP) reconstruction image. The differences in the dimensions among control, portal hypertension, and common bile duct obstruction groups were compared using one-way analysis of variance. Results: The cisterna chyli was shown in 91% of cases on FS-T2WI, while the thoracic duct appeared in 70% of the MIP images. The common configuration of the cisterna chyli was tubular or saccular in 73%. Eighty thoracic ducts had a slight turn declining to the left at the level of T8,10. There was a significant difference in the transverse diameter of the thoracic duct between the portal hypertension group and other groups (F = 5.638, P = 0.005). Conclusion: Nonenhanced MRI is feasible for locating and depicting the morphological features of the thoracic duct. Portal hypertension may influence the dimension of the thoracic duct. J. Magn. Reson. Imaging 2010;32:94,100. © 2010 Wiley-Liss, Inc. [source]


    Mechanical properties of particulate-filler/woven-glass-fabric-filled vinyl ester composites

    JOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 1 2010
    L. Yusriah
    Studies of the effect of particulate fillers on specific mechanical properties of vinyl ester epoxy (VE) reinforced with woven glass fiber composites were carried out with different filler types and particulate filler contents (1%, 3%, and 5% by weight). Two types of particulate filler were used, i.e., calcium carbonate (CC) and phenolic hollow microspheres (PHMS). The composites were prepared by using a hand lay-up and vacuum bagging method. Woven glass fabric composites filled with particulate PHMS were observed to have better specific flexural strength and specific impact strength, as well as lower density, than those filled with particulate CC. Morphological features determined by scanning electron microscope (SEM) proved that the PHMS filler experienced good bonding in the VE matrix, a feature which contributed to the improvement in the properties of the composites. The incorporation of particulate fillers into the composites also influenced the storage modulus with a minimal effect on Tg. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers [source]


    Morphological features of TMPRSS2,ERG gene fusion prostate cancer,

    THE JOURNAL OF PATHOLOGY, Issue 1 2007
    J-M Mosquera
    Abstract The TMPRSS2,ETS fusion prostate cancers comprise 50,70% of the prostate-specific antigen (PSA)-screened hospital-based prostate cancers examined to date, making it perhaps the most common genetic rearrangement in human cancer. The most common variant involves androgen-regulated TMPRSS2 and ERG, both located on chromosome 21. Emerging data from our group and others suggests that TMPRSS2,ERG fusion prostate cancer is associated with higher tumour stage and prostate cancer-specific death. The goal of this study was to determine if this common somatic alteration is associated with a morphological phenotype. We assessed 253 prostate cancer cases for TMPRSS2,ERG fusion status using an ERG break-apart FISH assay. Blinded to gene fusion status, two reviewers assessed each tumour for presence or absence of eight morphological features. Statistical analysis was performed to look for significant associations between morphological features and TMPRSS2,ERG fusion status. Five morphological features were associated with TMPRSS2,ERG fusion prostate cancer: blue-tinged mucin, cribriform growth pattern, macronucleoli, intraductal tumour spread, and signet-ring cell features, all with p -values < 0.05. Only 24% (n = 30/125) of tumours without any of these features displayed the TMPRSS2,ERG fusion. By comparison, 55% (n = 38/69) of cases with one feature (RR = 3.88), 86% (n = 38/44) of cases with two features (RR = 20.06), and 93% (n = 14/15) of cases with three or more features (RR = 44.33) were fusion positive (p < 0.001). To our knowledge, this is the first study that demonstrates a significant link between a molecular alteration in prostate cancer and distinct phenotypic features. The strength of these findings is similar to microsatellite unstable colon cancer and breast cancer involving BRCA1 and BRCA2 mutations. The biological effect of TMPRSS2,ERG overexpression may drive pathways that favour these common morphological features that pathologists observe daily. These features may also be helpful in diagnosing TMPRSS2,ERG fusion prostate cancer, which may have both prognostic and therapeutic implications. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source]


    Some Segmental Features on the Structure of the Aortic Wall of the Dog

    ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2004
    A. M. Orsi
    Summary Structural features of segmental parts of the aorta of the dog were studied by light microscopy (LM) and scanning electron microscopy (SEM). The variability in the wall architecture composition and vascular thickness of the ascending (T2-3 level), thoracic (T7-8 level) and abdominal (L6-7 infrarenal level) segments of the aorta was analysed. Morphological features such as presence of intimal folds, pattern of the medial myoconnective components with segmental variations in the number of elastic lamellae, whose relative number was higher in the thoracic aorta (ascending and descending parts), compared with the abdominal aorta, and a network of connective (stromal) elements formed by elastic and collagen lamellae and fibres in the adventitia were observed. The results were discussed on a histophysiological basis, because small but significant segmental differences had been characterized in the aortic wall structure of the dog. [source]


    Variable morphology of the sacrum in a Chinese population

    CLINICAL ANATOMY, Issue 5 2009
    Li-Ping Wu
    Abstract Although several morphological variations of sacrum have been reported in western populations, little attention has been paid to this anatomic issue in eastern people, and classification of sacral variability in particular. In this research of sacral morphology in Chinese people, we investigated and measured thoroughly and systematically 203 specimens of intact dry Chinese adult sacra. Morphological features of sacral variations were observed by visual inspection, and correlation parameters of variability were measured with a vernier caliper. The incidence of sacral variations was calculated. We found that the overall rate of sacral variations was 58.1% (male: 57.4%; female: 59.5%). The anatomical variants that we observed fell into the following five categories: accessory auricular surface (25 specimens, 12.3%); sacral skewness (48 specimens, 23.6%); transitional vertebra (34 specimens, 16.7%); sacral spina bifida occulta (57 specimens, 28.1%), Degrees I, II, and III of which were 36, 14, and 7 specimens, respectively; multiple variations (42 specimens, 20.7%), the types of which were diversified. This study reveals that sacral variations are common in Chinese population. The sacral variants in anatomic morphology should be taken into consideration when diagnosing and treating sacrum-related diseases. Clin. Anat. 22:619,626, 2009. © 2009 Wiley-Liss, Inc. [source]


    Peripheral endothelial cells are not reliable in differentiating primary benign and malignant hepatocellular lesions in fine needle aspirates of the liver

    CYTOPATHOLOGY, Issue 3 2002
    GORDON H. YU
    The distinction of hepatocellular carcinoma (HCC) from benign lesions of the liver in fine needle aspiration (FNA) specimens can be problematic. In an attempt to separate well-differentiated HCC from benign hepatocellular lesions, the presence of tissue fragments displaying peripheral endothelial cells (PE) has been proposed in a previous study as a useful feature in favour of malignancy. In this study, we evaluated slides from 59 cases of liver masses undergoing FNA (19 HCC, 40 benign) and evaluated them for the presence of tissue fragments containing PE. We found that 90% of cases of HCC contained tissue fragments in which PE were either focally present or abundant. However, 68% of cases containing only benign hepatocytes also contained tissue fragments in which PE were at least focally present. In addition, it appears that within the group of benign lesions, the presence of PE was related to the overall cellularity of the specimen rather than the specific nature of the lesion. Thus, the presence of PE in tissue fragments does not, in isolation, appear to be a useful morphological feature for the separation of benign and malignant hepatocellular lesions in FNA material. [source]


    Microtubule-dependent organization of subcortical microfilaments in the early Drosophila embryo

    DEVELOPMENTAL DYNAMICS, Issue 3 2007
    Maria Giovanna Riparbelli
    Abstract Dynamic alterations in the spatial organization of cytoskeletal elements constitute a prominent morphological feature of the early, syncytial stages of embryogenesis in Drosophila. Here, we describe and characterize the dynamic behavior of cytoplasmic, subcortical microfilaments, which form a series of nucleus-associated structures, at different phases of the simultaneous nuclear division cycles characteristic of early Drosophila embryos. Remodeling of the cytoplasmic microfilament arrays takes place in parallel to the established cyclic reorganization of cortical microfilament structures. We provide evidence that the cortical and subcortical microfilament populations organize independently of each other, and in response to distinct instructive cues. Specifically, formation of subcortical microfilament structures appears to rely on, and spatially mirror, the organization of polarized microtubule arrays, while cortical microfilament restructuring constitutes a centrosome-dependent process. Genetic analysis identifies a requirement for SCAR, a key mediator of Arp2/3-based microfilament dynamics, in organization of subcortical microfilament structures. Developmental Dynamics 236:662,670, 2007. © 2007 Wiley-Liss, Inc. [source]


    Histochemical analysis of lymphatic endothelial cells in lymphostasis

    MICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2001
    Rui-Cheng Ji
    Abstract The ultrastructure of endothelial cells of intestinal lymphatics and the thoracic duct (TD) and the relation to lymphostasis were examined in rats and monkeys. Localization of 5,-nucleotidase (5,-Nase) and endothelial nitric oxide synthase (eNOS) was studied. In normal lymphatic endothelial cells, 5,-Nase reaction product was evenly deposited on the cell surface in vivo and on cultured TD endothelial cells (TDECs), whereas eNOS was evenly distributed throughout the nucleus and cytoplasm. TDECs had a long filamentous process extending towards the subendothelial extracellular matrix but became flat and regular within 30,40 minutes after gastric perfusion with olive oil. According to their electron-density, two types of cells were found in the TD endothelial layer. The cells with low electron-density exhibited stronger 5,-Nase activity. Valves were bicuspid formations and the valvular endothelial surface of the convex side showed weaker 5,-Nase activity than the concave side. During TD blockage-induced lymphostasis in rats, the 5,-Nase product was almost not discernible in the TDECs within 2 weeks. Larger vesicles were found in the endothelial cytoplasm of the ligated TD. Their number decreased after 6,12 weeks. The small intestinal lymphatics in the mucosa and submucosa were dilated, with numerous open intercellular junctions. The endothelial lining appeared to have reduced activities for 5,-Nase and eNOS in 9 of 11 experimental animals. The results indicated that the inability of the open intercellular junctions, normally working as one-way endothelial flap valves, may be a key morphological feature after TD blockage. Reduced eNOS and 5,-Nase may functionally influence contractile activity and transport capability of the lymphatic vessels in the lymphostasis. Microsc. Res. Tech. 55:70,80, 2001. © 2001 Wiley-Liss, Inc. [source]


    Proposed neuropathological criteria for the post mortem diagnosis of multiple system atrophy

    NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 6 2007
    J. Q. Trojanowski
    This report summarizes the recommendations of the multiple system atrophy (MSA) Working Group on Diagnostic Neuropathology Criteria for MSA that was part of an international MSA Workshop held on 26 and 27 April 2007 in Boston, MA. The workshop was supported by a grant from the National Institute of Neurological Disorders and Stroke that was intended to convene a group of international experts to revise and update criteria for the clinical and neuropathological diagnosis of MSA. The MSA Workshop recognized the glial cytoplasmic inclusions (GCIs) composed of filamentous alpha-synuclein as a defining morphological feature of MSA, and it recommends that widespread GCIs should be a criterion for the definite neuropathological diagnosis of MSA. The deliberations and recommendations of the Working Group on Diagnostic Neuropathology Criteria for MSA are summarized in this report. [source]


    Gas seeps linked to salt structures in the Central Adriatic Sea

    BASIN RESEARCH, Issue 4 2008
    Riccardo Geletti
    ABSTRACT The analyses of about 800 km of Chirp sub-bottom profilers and 600 km2 of Multibeam data acquired during the 2005 and 2007 surveys of the R/V OGS Explora, and their correlation with one new, and several public, multichannel seismic profiles, allow us to propose a relation between the distribution of gas seepages, fracture systems and deep salt features present in the Central Adriatic Sea. Gas seepage is evident from pockmarks on the seabed and in the shallow sub-bottom, where acoustic chimneys and bright spots have been highlighted and analyzed. The Mid-Adriatic Depression (MAD) is a distinct morphological feature in the Central Adriatic Sea elongated in a NE,SW direction. The area is affected by salt doming of Triassic evaporites which cause the two main alignments of the Mid-Adriatic Ridge as far as the Palagruza High and the Jabuka Ridge. These salt tectonics have existed since, at least, Paleogene times and are still active: they characterize sectors with less resistance to deformation produced by successive regional compressive regimes that have affected the area differently during the different geodynamic phases. Gas-seep features are distributed preferentially above and along the fracture systems produced above and around the salt mounds. [source]


    Thyroid fine needle aspiration: the morphological features on ThinPrep® slide preparations.

    CYTOPATHOLOGY, Issue 6 2003
    Eighty cases with histological control
    This study had several purposes: to define cytomorphological features of thyroid cells that might be modified by alcohol fixation; to optimize May-Grünwald,Giemsa (MGG) staining on ThinPrep® (TP; Cytyc Inc., Bexborough, MA, USA) slides and to compare the diagnostic accuracy of slides prepared by a liquid-based method with those obtained by conventional technique. This study included 120 cases of ultrasound-guided fine needle aspiration (FNA) of the thyroid and 55 FNAs performed on surgically resected thyroid specimens. Histological control was available in 80 cases. In the first group of 120 FNAs, a split-sample technique was used for the TP. Three screenings were performed: first, an individual screening of the conventional smears (CS) and of the TP, a second screening to compare cells observed on the TP with the histological control and a third screening to assess the previously defined diagnostic criteria. Twenty-seven TP cases (22%) were considered unsatisfactory for diagnosis compared with 10 in CS (8%). The high rate of unsatisfactory cases with TP is likely to be due to the use of the split-sample technique. The sensitivity was 94% for CS and 81% for TP. The specificity was 67% and 60% for CS and TP, respectively. Two occult papillary carcinomas were missed by both methods. As for the MGG staining, the modified technique used for TP resulted in the same quality as the standard procedure. Conversely, TP did however induce uncommon morphological features. In this study, sensitivity and specificity levels are higher for CS than for TP; the difference may be explained by the fact that the methanol fixative used for TP induces some cytological alterations, especially in oncocytic tumours and lymphocytic thyroïditis. [source]


    Mesothelioma Symposium 11.30,12.30 Tuesday 16 September 2003

    CYTOPATHOLOGY, Issue 2003
    Darrel Whitaker Dr
    The diagnosis of malignant mesothelioma on the cytology of serous effusions is a two-phase process. First is to determine that the effusion is malignant based on morphological features such as a highly cellular fluid with many large three dimensional cell aggregates, and/or the recognition of minor malignant criteria including prominent cell engulfment, uniformly present very prominent nucleoli, or the finding of very large (giant) cells. In cell block sections, strong positive staining with EMA often with cell membrane accentuation provides compelling support for a cytological diagnosis of malignancy. Second is to recognize that the malignant cells have a mesothelial phenotype and do not represent metastatic malignancy (usually adenocarcinoma). Criteria in support of mesothelioma include the lack of a ,two cell' population, that is one native (mesothelial) and one foreign (metastatic), cells with abundant dense staining cytoplasm, the presence of ,windows' where mesothelioma cells lie in close apposition and intracytoplasmic glycogen presenting either as small peripheral vacuoles on MGG stained smears or large yellow refractile crescents on Papanicolaou stained smears. In addition, mesothliomas often possess connective tissue stromal cores occurring as either well-formed collagen within papillary aggregates or lying free as pink (MGG) or light green (Pap) amorphous material in the background of the smear or in loose association with mesothelioma cells. Finally small orange staining squamous-like cells can occasionally be identified and sometimes this may be a very prominent finding and has resulted in the false impression of a squamous cell carcinoma. Almost certainly these cells represent apoptotic tumour cells. The connective tissue mucin hyaluronic acid may be found as a net-like pattern in the smear background or as large hard-edged magenta-stained vacuoles on MGG-stained smears. Cell block sections provide architectural information and it is usually possible to separate mesothelioma aggregates with their cuboidal cells, central nuclei and abundant dense cytoplasm arranged in solid, papillary or hollow clusters from those of adenocarcinoma with less dense, often foamy cytoplasm, often composed of columnar cells with elongated nuclei. Aggregate form in adenocarcinoma can be variable but true acini are a rare finding. These cell block sections provide an ideal medium for histochemistry (PAS with and without diastase digestion) and immunocytochemistry. By using a panel of antibodies (Calretinin and CK 5/6, BerEp4, CEA, B72.3) it is almost always possible to distinguish mesothelioma from metastatic adenocarcinoma. Calretinin and CK 5/6 positive staining and absent staining with BerEp4, CEA and B72.3 is considered diagnostic of mesothelioma. [source]


    Morphological irregularities and features of resistance to apoptosis in the dcp-1/pita double mutated egg chambers during Drosophila oogenesis

    CYTOSKELETON, Issue 1 2005
    Ioannis P. Nezis
    Abstract In the present study, we demonstrate the most novel characteristic morphological features of Drosophila egg chambers lacking both dcp-1 and pita functions in the germline cells. Dcp-1 is an effector caspase and it has been previously shown to play an important role during Drosophila oogenesis [McCall and Steller, 1998 : Science 279 : 230,234; Laundrie et al., 2003 : Genetics 165 : 1881,1888; Peterson et al., 2003 : Dev Biol 260 : 113,123]. The completion of sequencing and annotation of the Drosophila genome has revealed that the dcp-1 gene is nested within an intron of another distinct gene, called pita, a member of the C2H2 zinc finger protein family that regulates transcriptional initiation. The dcp-1,/,/pita,/, nurse cells exhibit euchromatic nuclei (delay of apoptosis) during the late stages of oogenesis, as revealed by conventional light and electron microscopy. The phalloidin-FITC staining discloses significant defects in actin cytoskeleton arrangement. The actin bundles fail to organize properly and the distribution of actin filaments in the ring canals is changed compared to the wild type. The oocyte and the chorion structures have been also modified. The oocyte nucleus is out of position and the chorion appears to contain irregular foldings, while the respiratory filaments obtain an altered morphology. The dcp-1,/,/pita,/, egg chambers do not exhibit the rare events of spontaneously induced apoptosis, observed for the wild type flies, during mid-oogenesis. Interestingly, the mutated egg chambers are protected by staurosporine-induced apoptosis in a percentage of 40%, strongly suggesting the essential role of dcp-1 and/or pita during mid-oogenesis. Cell Motil. Cytoskeleton 60:14,23, 2005. © 2004 Wiley-Liss, Inc. [source]


    Pleomorphic adenoma: Cytologic variations and potential diagnostic pitfalls

    DIAGNOSTIC CYTOPATHOLOGY, Issue 1 2009
    Uma Handa M.D.
    Abstract The diverse morphological features encountered in pleomorphic adenoma (PA) may cause diagnostic errors in fine needle aspiration cytology (FNAC). The present study was performed to evaluate the variations in the cytological features of pleomorphic adenoma and to assess the efficacy of FNAC in its diagnosis. Fifty cases diagnosed as PA on FNAC were retrieved from the records of the Pathology Department. Cytologic smears and sections were reviewed and the cytologic diagnoses were compared with the definitive histologic diagnoses. In cases correctly diagnosed on aspiration, morphological variables like patterns of the epithelial component, type and extent of the mesenchymal matrix, metaplastic cells, hyaline globules, cystic change, giant cells, crystalline deposits, nuclear inclusions/grooves, and nuclear atypia were evaluated. The extreme diversity in morphologic features seen in histologic sections was reflected in the smears of PA. Metaplastic changes were observed more frequently in sections, while nuclear changes like inclusions/grooves were more commonly seen in smears. Other morphological features like cylindromatous pattern, giant cells and crystalline deposits were observed with equal frequency in smears and sections. Cytohistologic agreement was present in 45 of the 50 cases (90%). In 5 cases diagnosed as pleomorphic adenoma on FNAC, the histology revealed 1 case each of schwannoma, perineurioma, ectomesenchymal chondromyxoid tumor of tongue, adenoid cystic carcinoma and mucoepidermoid carcinoma. FNAC is a fairly accurate pre-operative procedure for the diagnosis of PA. The cytopathologist needs to be aware of the cytologic variations in pleomorphic adenoma so as to avoid diagnostic errors. Diagn. Cytopathol. 2009. © 2008 Wiley-Liss, Inc. [source]


    Secretory activity in medullary thyroid carcinoma: A cytomorphological and immunocytochemical study

    DIAGNOSTIC CYTOPATHOLOGY, Issue 6 2007
    D.Sc., Dilip K. Das M.B.B.S., F.R.C.Path., Ph.D.
    Abstract Medullary thyroid carcinoma (MTC) is a relatively rare thyroid malignancy of C-cell origin that secretes calcitonin. Although its varied cytomorphologic features are well described in literature, very little is mentioned about the morphologic manifestation of its secretory activity. This study, based on nine fine needle aspiration (FNA) samples from eight MTC patients, is an attempt to present the varied cytomorphologic features suggesting secretory activity in MTC as observed in Papanicolaou and MGG stained FNA smears and correlate them with the immunocytochemical (ICC) staining for calcitonin performed on FNA smears and the serum calcitonin values. The average number of cells in these nine samples was as follows: oval/triangular/plasmacytoid (56.7%), small round (23.6%), spindle-shaped (12.7%), and miscellaneous (7.1%). The cytomorphological features suggesting secretory activity, viz., fine cytoplasmic vacuoles, azurophillic granules, marginal vacuoles, and intracytoplasmic lumina (ICL) with secretions were present in eight, eight, five, and six samples, respectively. Material likely to be amyloid, based on morphological features, was present extracellularly in three samples and both intracellularly and extracellularly in six samples. Immunocytochemically, all the nine samples stained for calcitonin and all the three stained for chromogranin showed positive cytoplasmic reaction in the neoplstic cells. The background amyloid (in six samples), the coarse cytoplasmic granules (in two samples), and the contents of ICL (in one sample) were found to be positively stained for calcitonin. The intracytoplasmic secretory material appeared to be diffusing out of some cells both in the routine MGG stained smears and in the smears stained for calcitonin. Histopathology reports of seven samples in six patients confirmed the cytodiagnosis of MTC in all. Baseline serum calcitonin values in three cases and postoperative serum calcitonin levels during follow-up in three others were high. Thus, our study highlighted the morphological manifestations of secretory activity in MTC and the nature of secretory material as calcitonin, supported by immunocytochemical staining and serum calcitonin level. Diagn. Cytopathol. 2007;35:329,337. © 2007 Wiley-Liss, Inc. [source]


    The significance of the diagnosis of atypia in breast fine-needle aspiration

    DIAGNOSTIC CYTOPATHOLOGY, Issue 5 2004
    Jennifer C. Lim M.D.
    Abstract The diagnosis of atypia in breast fine-needle aspiration (FNA) continues to be an area of debate in cytology practice. The aim of this study was to assess the clinical significance of this term and to evaluate potential morphological criteria, which would determine the patient's outcome. A computer-based search was carried out to retrieve breast FNAs performed between 1990 and 2000 that were diagnosed as atypical. Cases followed by surgical resection were reexamined for the presence of morphological features potentially differentiating benign and malignant lesions. Out of 1,568 breast FNAs, there were 64 cases (4%) with a diagnosis of atypia. Thirty-eight cases had surgical follow-up material that revealed malignancy in 14 cases (37%) and benign lesions in 24 cases (63%). The benign diagnostic categories included fibrocystic change (12/24), fibroadenoma (3/24), tubular adenoma (2/24), and nonspecific findings (7/24). The malignant diagnoses included ductal carcinoma (9/14), lobular carcinoma (3/14), ductal carcinoma in situ (DCIS; 1/14), and tubular carcinoma (1/14). The evaluation of cytological criteria used to differentiate benign from malignant lesions (i.e., cellularity, loss of cohesion, myoepithelial cells, nuclear enlargement, nuclear overlap, prominent nucleoli) revealed significant overlap between benign and malignant cases, particularly in cases of fibroadenoma, tubular adenoma, and proliferative breast disease. The surgical follow-up of four hypocellular cases revealed lobular carcinoma in two cases and ductal carcinoma in the remaining two cases. Our study confirmed that the diagnosis of atypia is clinically significant because it is associated with a high probability of malignancy. No morphological criterion is able to reliably differentiate benign and malignant lesions in cases diagnosed with atypia. Diagnosis of atypia is particularly significant in hypocellular cases. We recommended that breast FNAs with a diagnosis of atypia be evaluated further histologically. Diagn. Cytopathol. 2004;31:285,288. © 2004 Wiley-Liss, Inc. [source]


    Structural and ultrastructural studies of male reproductive tract and spermatozoa in Xylocopa frontalis (Hymenoptera, Apidae)

    ACTA ZOOLOGICA, Issue 2 2010
    B. S. Fiorillo
    Abstract Fiorillo, B. S., Zama, U., Lino-Neto, J. and Báo, S. N. 2010. Structural and ultrastructural studies of male reproductive tract and spermatozoa in Xylocopa frontalis (Hymenoptera, Apidae). ,Acta Zoologica (Stockholm) 91: 176,183. In Xylocopa frontalis the reproductive tract is composed of testes, deferent ducts, seminal vesicles, accessory glands and an ejaculatory duct. Each testis comprises four testicular tubules in which multiple cysts are present containing approximately 64 spermatozoa per cyst. The seminal vesicle consists of an epithelium, a thick basement lamina and a muscular external sheet. In the luminal region some vesicles can be observed; however, the epithelial cells of the seminal vesicle do not display morphological features associated with secretory functions. The spermatozoa, measuring approximately 260 µm long, are similar to the hymenopteran pattern. The head region consists of an acrosome with an inner perforatorium that penetrates an asymmetrical nuclear tip. The nucleus is linear, electron-dense and its posterior tip projects into the beginning of the axoneme. The centriolar adjunct is asymmetric with many electron-lucent lacunae interspersed throughout. The axoneme has the 9 + 9 + 2 pattern of microtubules and in the posterior region the central microtubules finish first, followed by the doublets and finally the accessory microtubules. The mitochondrial derivatives are asymmetric in both length and diameter with paracrystalline material present only in the larger one. These features may be useful characters for taxonomy and phylogenetic studies. [source]


    On the morphology of Acanthostomum spiniceps (Looss, 1896) and A. absconditum (Looss, 1901) (Digenea: Cryptogonimidae: Acanthostominae) with particular reference to the juvenile stage

    ACTA ZOOLOGICA, Issue 3 2006
    Mohammed Hasan Ibraheem
    Abstract The morphology of juvenile and adult stages of Acanthostomum spiniceps and A. absconditum, from bagrid fish of the river Nile in Egypt, was studied with both light and scanning electron microscopy. In early juveniles, circumoral spines are absent and the entire body surface is covered with tegumental spines. Late juveniles show gradual differentiation of the circumoral tegument into a collar of spines associated with a reduction in density of tegumental spines at the posterior extremity of the body. Genital primordia appear when juveniles are about 1.75 mm long. The distributions of tegumental spines on adult A. spiniceps and A. absconditum are similar. Spines are denser on the dorsal and ventral surfaces of the anterior and middle parts of the body and less dense towards the posterior end. The tegumental fold surrounding the ventral sucker of A. absconditum has spines while the fold of A. spiniceps lacks them. The most important morphological features differentiating both species are the number of circumoral spines, body shape, ratio of body length to width, sucker sizes, and the presence or absence of spines on the ventral sucker. [source]


    CEC column behaviour of butyl and lauryl methacrylate monoliths prepared in non-aqueous media

    ELECTROPHORESIS, Issue 4 2009
    Amparo Cantó-Mirapeix
    Abstract Polymeric monolithic stationary phases for capillary electrochromatography were prepared using two bulk monomers, butyl methacrylate (BMA) and lauryl methacrylate (LMA), by in situ polymerization in non-aqueous media. The effect of 1,4-butanediol/1-propanol ratio on porous properties was investigated separately for each monomer, keeping the proportion of monomers to pore-forming solvents fixed at 40:60,wt:wt. Also, mixtures of BMA and LMA at different 1,4-butanediol/1-propanol ratios were studied for tailoring the morphological features of the monolithic columns. The chromatographic performance of the different columns was evaluated by means of van Deemter plots of polycyclic aromatic hydrocarbons. Mercury-intrusion porosimetry, SEM, and nitrogen-adsorption measurements were also performed in order to understand their retention behaviour and porous properties. A comparison of these features was also performed for monoliths made with one bulk monomer (BMA or LMA) and with mixtures of both. These mixed monoliths showed satisfactory efficiencies and analysis times compared with those made with one bulk monomer; thus, the BMA,LMA monoliths constitute an attractive alternative to manipulate the electrochromatographic properties of methacrylate beds in CEC. [source]


    A novel case of haemoglobin H disease associated with clinical and morphological characteristics of congenital dyserythropoietic anaemia type I

    EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2002
    M. Antonelou
    Abstract: We report, for the first time, an unusual case of congenital anaemia with the clinical diagnosis of haemoglobin H disease complicated by morphological features at the light and electron microscopy level very similar to those of CDA-I. The red cell indices and the globin chain biosynthetic ratio were not characteristic of the defective haemoglobin genotype. The haematological, clinical and morphological data strongly suggest the novel coexistence of the two defects in a patient. The disease is characterised by a unique dyserythropoietic phenotype of diagnostic importance, which possibly brings new data regarding the reciprocal interaction between the two diseases, especially concerning a specific abnormality in globin chain synthesis in CDA-I, as previously suggested. [source]


    The neural networks of music

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2002
    E. Baeck
    Recent neuropsychological, transcranial Doppler sonographic, positron emission tomographic and functional nuclear magnetic resonance studies have indicated that musical perception is not dependent on the right hemisphere but on neural networks corresponding to the fundamental components of music in both hemispheres. In the brain there is no centre for music. Musicians have cerebral characteristics, anatomical as well as functional, which are correlated with the age at which they began their musical studies. This argues for cortical reorganization as a result of musical training. Whether these characteristics are to be ascribed to cortical plasticity alone, or to an innate structural property, or to both, remains an open question, however. Investigation of chromosomal defects, biochemical abnormalities and morphological features of congenital and degenerative brain diseases can provide further insight into the cerebral substrate of musicality. [source]


    Tyrosine hydroxylase-positive neurons intrinsic to the human striatum express the transcription factor Nurr1

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2004
    Martine Cossette
    Abstract The putative dopaminergic (DA) neurons intrinsic to human striatum were studied to determine their similarity with DA neurons of the substantia nigra pars compacta (SNpc). The comparison was based on morphological features and on the presence or absence of Nurr1, an orphan receptor of the nuclear receptor family that is essential for the expression of DA phenotype by developing SNpc neurons. Immunohistochemistry for the neuronal nuclear protein (NeuN; a neuronal marker) and in situ hybridization for tyrosine hydroxylase (TH) and/or Nurr1 were applied to post-mortem tissue obtained from seven normal individuals. On one hand, the TH-positive multipolar neurons in the human striatum, which were subdivided into three groups according to their size and pattern of dendritic arborization, were found to be morphologically similar to TH-positive neurons of the SNpc. The distribution frequency of striatal TH-positive neurons, according to their diameter, closely matches the frequency observed for multipolar TH-positive cells in the SNpc. On the other hand, the proportion of neurons expressing Nurr1 and TH mRNA transcripts on single striatal section was similar to the proportion of TH-immunoreactive neurons observed on adjacent sections. More importantly, in each striatum analysed, virtually all cells that stained for TH also expressed NeuN and Nurr1. This study provides novel data that confirm the existence of DA neurons intrinsic to the human striatum. It also provides the first evidence for the existence of striking morphological and chemical similarities between the DA neurons present at striatal level and those that populate the SNpc. [source]


    Colloidal Films That Mimic Cilia

    ADVANCED FUNCTIONAL MATERIALS, Issue 18 2010
    Fang Liu
    Abstract Cilia are wavy hair-like structures that extend outward from surfaces of various organisms. They are classified into two general categories, primary cilia, which exhibit sensing attributes, and motile cilia, which exert mechanical forces. A new poly(2-(N,N -dimethylamino)ethyl methacrylate- co -n-butyl acrylate- co - N,N -(dimethylamino) azobenzene acrylamide) (p(DMAEMA/nBA/DMAAZOAm) copolymer is prepared using colloidal synthesis, which, upon coalescence, form films capable of generating surfaces with cilia-like features. While film morphological features allow the formation of wavy whiskers, the chemical composition of the copolymer facilitates chemical, thermal, and electromagnetic responses manifested by simultaneous shape and color changes as well as excitation wavelength dependent fluorescence. These studies demonstrate that synthetically produced polymeric films can exhibit combined thermal, chemical, and electromagnetic sensing leading to locomotive and color responses, which may find numerous applications in sensing devices, intelligent actuators, defensive mechanisms, and others. [source]


    Comparative study and molecular characterization of ectomycorrhizas in Tilia americana and Quercus pubescens with Tuber brumale

    FEMS MICROBIOLOGY LETTERS, Issue 1 2002
    G Giomaro
    Abstract Mycorrhizas of Tuber brumale on Quercus pubescens and Tilia americana were obtained in vitro using micropropagated plantlets. Mycelium pure cultures were used for inoculation. Both the mycelium used for the inoculations, as well as the mycorrhizas which were obtained, were identified using several molecular approaches: analysis of the ITS region, polymerase chain reaction (PCR) specific primers and sequencing. The mycorrhizas were described from a morphological standpoint. Some of their biometric characteristics were different in bass-wood than they were in oak, thus showing the influence of the host plant on several of the morphological features believed to be necessary for the identification of the species. Considering the variability of their morphological characteristics, molecular analysis proved to be a necessary tool for the recognition of the mycorrhizas of Tuber spp. [source]


    Chytrid infections of Daphnia pulicaria: development, ecology, pathology and phylogeny of Polycaryum laeve

    FRESHWATER BIOLOGY, Issue 4 2006
    PIETER T. J. JOHNSON
    Summary 1. We combined ecological surveys, life table studies, microscopy and molecular sequencing to determine the development, ecology, pathology and phylogeny of Polycaryum laeve, an endoparasite of cladocerans. We report the first records of P. laeve from North America, where we have used a polymerase chain reaction primer and microscopic examination to confirm infections in 14 lakes. Infections are highly pathogenic and caused increased mortality, reduced growth, and reproductive castration in Daphnia pulicaria during life table studies. 2. Biweekly data from Allequash Lake (Wisconsin, U.S.A.) throughout 2003 indicated that fecundity and infection prevalence were inversely correlated. Infection prevalence was highest in late winter and early spring (up to 80%) and lowest during late summer. Epidemics were generally followed by sharp declines in host population density (up to 99%). 3. Within the haemocoel of its host, P. laeve forms thick-walled sporangia, which occur systemically in later stages of infection. Fungal thalli associate closely with muscle fibres and connective tissue, leading to degeneration as the infection becomes advanced. Following death of the host, flagellated zoospores are released through an exit papilla on the sporangium. Based on the infection-induced castration of the host and increases in infection prevalence with Daphnia size, we postulate that transmission is horizontal, but may be indirect through an additional host or free-living stage. 4. Molecular and morphological data clearly indicate that P. laeve belongs in the fungal phylum Chytriodiomycota, order Blastocladiales. Based on ribosomal RNA gene sequences and morphological features, we transfer the genus Polycaryum from the Haplosporidia to the Chytridiomycota, and designate a lectotype and epitype for P. laeve. Considering the high prevalence of P. laeve infection within Daphnia populations, the frequency with which we detected infections among lakes, and the keystone importance of large-bodied Daphnia in aquatic food webs, we suggest that P. laeve may exert a regulatory influence on Daphnia populations in lake ecosystems. [source]