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Morphological Similarities (morphological + similarity)
Selected AbstractsIdentification and characterization of ectosymbionts of distinct lineages in Bacteroidales attached to flagellated protists in the gut of termites and a wood-feeding cockroachENVIRONMENTAL MICROBIOLOGY, Issue 1 2006Satoko Noda Summary Bacterial attachments to nearly the entire surface of flagellated protists in the guts of termites and the wood-feeding cockroach Cryptocercus are often observed. Based on the polymerase chain reaction-amplified 16S rRNA gene sequences, we investigated the phylogenetic relationships of the rod-shaped, attached bacteria (ectosymbionts) of several protist species from five host taxa and confirmed their identity by fluorescence in situ hybridizations. These ectosymbionts are affiliated with the order Bacteroidales but formed three distinct lineages, each of which may represent novel bacterial genera. One lineage consisted of the closely related ectosymbionts of two species of the protist genus Devescovina (Cristamonadida). The second lineage comprised three phylotypes identified from the protist Streblomastix sp. (Oxymonadida). The third lineage included ectosymbionts of the three protist genera Hoplonympha, Barbulanympha and Urinympha in the family Hoplonymphidae (Trichonymphida). The ultrastructural observations indicated that these rod-shaped ectosymbionts share morphological similarities of their cell walls and their point of attachment with the protist but differ in shape. Elongated forms of the ectosymbionts appeared in all the three lineages. The protist cells Streblomastix sp. and Hoplonympha sp. display deep furrows and vane-like structures, but these impressive structures are probably evolutionarily convergent because both the host protists and their ectosymbionts are distantly related. [source] External genital morphology of the ring-tailed lemur (Lemur catta): Females are naturally "masculinized"JOURNAL OF MORPHOLOGY, Issue 4 2008Christine M. Drea Abstract The extravagance and diversity of external genitalia have been well characterized in male primates; however, much less is known about sex differences or variation in female form. Our study represents a departure from traditional investigations of primate reproductive anatomy because we 1) focus on external rather than internal genitalia, 2) measure both male and female structures, and 3) examine a strepsirrhine rather than an anthropoid primate. The subjects for morphological study were 21 reproductively intact, adult ring-tailed lemurs (Lemur catta), including 10 females and 11 males, two of which (one per sex) subsequently died of natural causes and also served as specimens for gross anatomical dissection. Male external genitalia presented a typical masculine configuration, with a complex distal penile morphology. In contrast, females were unusual among mammals, presenting an enlarged, pendulous external clitoris, tunneled by the urethra. Females had a shorter anogenital distance and a larger urethral meatus than did males, but organ diameter and circumference showed no sex differences. Dissection confirmed these characterizations. Noteworthy in the male were the presence of a "levator penis" muscle and discontinuity in the corpus spongiosum along the penile shaft; noteworthy in the female were an elongated clitoral shaft and glans clitoridis. The female urethra, while incorporated within the clitoral body, was not surrounded by erectile tissue, as we detected no corpus spongiosum. The os clitoridis was 43% the length and 24% the height of the os penis. On the basis of these first detailed descriptions of strepsirrhine external genitalia (for either sex), we characterize those of the female ring-tailed lemur as moderately "masculinized." Our results highlight certain morphological similarities and differences between ring-tailed lemurs and the most male-like of female mammals, the spotted hyena (Crocuta crocuta), and call attention to a potential hormonal mechanism of "masculinization" in female lemur development. J. Morphol., 2008. © 2007 Wiley-Liss, Inc. [source] Establishment and characterization of immortalized human gingival keratinocyte cell linesJOURNAL OF PERIODONTAL RESEARCH, Issue 6 2008S. Gröger Background and Objective:, Primary human keratinocytes are used to analyze the properties of the oral epithelium and the early stages of oral bacterial infections. In vitro, these cells are characterized by their short life span and restricted availability. Approaches for culturing these cells will end after approximately 6,10 passages as a result of entry into apoptosis. For this reason, it is important to generate cell lines suitable for obtaining an unlimited source of cells. Therefore, the aim of the present study was to generate gingival keratinocyte cell lines and to compare their in vitro behaviour with those of primary human gingival keratinocytes. Material and Methods:, Primary human gingival keratinocytes were immortalized with a combination of the human papilloma virus onkoproteins E6 and E7. The pattern of the cytokeratins, involucrin and filaggrin was investigated by intracellular staining using flow cytometry. This method allows quantitative analysis of the expression of a variety of intracellular or extracellular markers. Results:, The immortalized cell lines showed many morphological similarities, expressing a cytokeratin pattern that is comparable with that of primary gingival keratinocytes. Furthermore, they developed transepithelial electrical resistance, which is a marker for the generation of tight junctions. These results indicate that the cells might be able to act as an epithelial barrier, reflecting the reaction of primary human cells. Conclusion:, The establishment of a continuous line of human gingival epithelial cells with functional characteristics of the epithelial barrier provides a valuable in vitro model for using to study the early steps of gingival/periodontal infections. [source] MORPHOLOGY, LIFE HISTORY, AND MOLECULAR PHYLOGENY OF STSCHAPOVIA FLAGELLARIS (TILOPTERIDALES, PHAEOPHYCEAE) AND THE ERECTION OF THE STSCHAPOVIACEAE FAM.JOURNAL OF PHYCOLOGY, Issue 6 2004The phenology, life history, ultrastructure of reproductive structures, and molecular phylogeny using rbcL and rDNA (5.8S, internal transcribed spacer 2, and partial 26S) gene sequences of Stschapovia flagellaris, endemic to the northwestern Pacific Ocean, were studied. This species was first classified in the order Delamareales together with Delamarea, Coelocladia, and Cladothele. Those three genera, however, were later transferred to Dictyosiphonales, whereas the systematic position of Stschapovia remained unclear. At Abashiri, Hokkaido, Japan, the species regenerated by forming a new erect thallus from a perennial crustose holdfast or by presumably parthenogenetic development of eggs released from the erect thallus. There was no alternation of generations. In winter, the monoecious erect thallus formed reproductive structures (i.e. plurilocular antheridia and oogonia) in the thickened part of the thallus. Sperm had a chloroplast with an eyespot and a long anterior and short posterior flagellum. Eggs contained numerous disc-shaped chloroplasts, physodes, and vacuoles. Neither sexual attraction of the presumptive sperm by eggs nor their sexual fusion was observed. Molecular phylogenetic analyses revealed the closest phylogenetic relationship between Stschapovia and Halosiphonaceae, and they grouped with Phyllariaceae and Tilopteridaceae (Tilopteridales s. s.). Stschapovia and Tilopteridaceae have several important morphological similarities: chloroplasts lacking pyrenoids, lack of sexual reproduction despite the release of obvious sperm, occurrence of monoecious gametophytes, and similarity in the early developmental pattern of the erect thallus. In conclusion, we propose the establishment of the new family Stschapoviaceae to accommodate Stschapovia and the placement of the family in the order Tilopteridales together with Tilopteridaceae, Halosiphonaceae, and Phyllariaceae. [source] Sulfide-rich metallic impact melts from chondritic parent bodiesMETEORITICS & PLANETARY SCIENCE, Issue 5 2010Devin L. SCHRADER We compare them with the H-metal meteorite, Lewis Cliff 88432. Phase diagram analyses suggest that SaW 005, MET 00428, and HOW 88403 were liquids at temperatures above 1350 °C. Tridymite in HOW 88403 constrains formation to a high-temperature and low-pressure environment. The morphology of their metal-troilite structures may suggest that MET 00428 cooled the slowest, SaW 005 cooled faster, and HOW 88403 cooled the quickest. SaW 005 and MET 00428 contain H-chondrite like silicates, and SaW 005 contains a chondrule-bearing inclusion that is texturally and compositionally similar to H4 chondrites. The compositional and morphological similarities of SaW 005 and MET 00428 suggest that they are likely the result of impact processing on the H-chondrite parent body. SaW 005 and MET 00428 are the first recognized iron- and sulfide-rich meteorites, which formed by impact on the H-chondrite parent body, which are distinct from the IIE-iron meteorite group. The morphological and chemical differences of HOW 88403 suggest that it is not from the H-chondrite body, although it likely formed during an impact on a chondritic parent body. [source] Forensic identification of the guitarfish species Rhinobatos horkelli, R. percellens and Zapteryx brevirostris using multiplex-PCRMOLECULAR ECOLOGY RESOURCES, Issue 1 2010B. DE-FRANCO Abstract Rhinobatos percellens, Rhinobatos horkelli and Zapteryx brevirostris, known as guitarfish, are commonly found inshore and caught by trawl nets. Recently, these species have been suffering sharp population declines. One of the main impediments to the development of conservation plans is the lack of information related to each species catch. Gathering this information is made more difficult by the fishermen's practice of removing parts of the animals before landing, as well as the morphological similarities among the three species. To address these issues, this work presents multiplex-PCR protocols that were developed to distinguish among these species using their genetic characteristics. [source] A New Species of Amphirhagatherium (Choeropotamidae, Artiodactyla, Mammalia) from the Late Eocene Headon Hill Formation of Southern England and Phylogeny of Endemic European ,anthracotherioids'PALAEONTOLOGY, Issue 5 2001Jerry J. Hooker A new species of artiodactyl, Amphirhagatheriumedwardsi sp. nov., is described from the Late Eocene (Priabonian) Headon Hill Formation of the Hampshire Basin, southern England. The Haplobunodontidae, in which Amphirhagatherium is usually placed, has recently been combined with the monotypic Choeropotamidae, both essentially European endemic families. New anatomical information is forthcoming from both the new species and recently published data on related species. A cladistic analysis of taxa included in the two families, the possible anthracotheriid Thaumastognathus and the enigmatic Tapirulus, was conducted to test the relationships implied by observed morphological similarities. The genus Anthracobunodon is shown to be paraphyletic and is here synonymized with Amphirhagatherium. Choeropotamus and Thaumastognathus are sister taxa nested with three species of Haplobunodon and Haplobunodon is paraphyletic and polyphyletic, but this clade is too weakly resolved internally for reliable taxonomic changes. LophiobunodonTapirulus are sister taxa nested with a fourth species of Haplobunodon. The synonymy of the Haplobunodontidae with the Choeropotamidae is upheld and close relationship of the family with the Anthracotheriidae is argued to be unlikely. Choeropotamids are inferred to have had mixed frugivorous and browsing herbivorous diets. They seem to have diversified in the northern parts of Europe, some terminal taxa having originated following southward dispersal. [source] Diagnostic utility of EWS break-apart fluorescence in situ hybridization in distinguishing between non-cutaneous melanoma and clear cell sarcomaPATHOLOGY INTERNATIONAL, Issue 9 2010Joon Seon Song Clear cell sarcoma (CCS) is a rare soft tissue sarcoma with morphological similarities to malignant melanoma (MM), but with a distinct genetic background that includes the chromosomal translocation t(12;22)(q13;q12). Clear cell sarcoma is often misdiagnosed as MM because of similarities in target locations and immunophenotypes. Eighteen cases with MM in non-cutaneous sites were subjected to fluorescence in situ hybridization (FISH) to assess EWS gene breakage. Tissue microarrays were constructed using formalin-fixed, paraffin-embedded tissue and the EWSR1 (22q12) dual-color, break-apart rearrangement probe (Vysis) was used. Two patients were classified as CCS with EWS gene rearrangement, with a mean of 67.5% positive cells per sample according to break-apart FISH. The remaining 16 patients lacked break-apart signals of the EWS gene. The presence of type 1 (EWS exon 8-ATF1 exon 4) fusion transcripts was confirmed in FISH-positive patients by RT-PCR. Retrospective analysis revealed that the masses were located in the foot and buttock, respectively. Morphologically, tumor cells were not typical for those of CCS or MM. Break-apart FISH is an accurate and convenient method for differentiating between MM and CCS. Molecular detection of EWS gene rearrangement, either by break-apart FISH or RT-PCR, is mandatory in subjects with melanotic tumors of soft tissue. [source] Geometric morphometric study of population variation in indigenous southern African craniaAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2007D. Franklin Much of our understanding of population variation in southern Africa is derived from traditional morphometric research. In the search for new perspectives, this paper reports on new geometric morphometric data examining cranial variation in 12 modern human populations from southern Africa. In total, 298 male Bantu-speaking individuals were studied. In addition, a small Khoisan (Khoikhoi and San) series was also examined. The purpose of this study was to investigate Khoisan-Bantu morphological similarities and differences, and to examine variation within both the Bantu-speaking and Khoisan populations. The three-dimensional coordinates of 96 landmarks were analyzed, using the shape-analysis software morphologika. Interpopulation variation was examined by calculating Procrustes distances between groups; a cluster analysis was then used to summarize phenetic relationships. A principal components analysis explored the relationships between populations; shape differences were visualized and explored using three-dimensional rendered models, and further interpreted using thin-plate splines. Morphological differences are present within and between the crania of Bantu-speaking and Khoisan individuals. The Khoisan demonstrate features (e.g., a pentagonoid vault, more rounded forehead contour, and a small and less prognathic face) that clearly distinguish them from Bantu-speaking populations. Although southern African Bantu-speaking populations are clearly closely related, they show population-specific features (e.g., the crania of more southerly populations (Xhosa, Southern Sotho, and Zulu) are characteristically more brachycephalic and less prognathic). This study suggests that differential admixture with adjacent Khoisan peoples has contributed to diversity within southern African Bantu-speaking populations. Am. J. Hum. Biol. 19:20,33, 2007. © 2006 Wiley-Liss, Inc. [source] Simulation of pH-dependent edge strand rearrangement in human ,-2 microglobulinPROTEIN SCIENCE, Issue 1 2006Sheldon Park Abstract Amyloid fibrils formed from unrelated proteins often share morphological similarities, suggesting common biophysicalmechanisms for amyloidogenesis. Biochemical studies of human ,-2 microglobulin (,2M) have shown that its transition from a water-soluble protein to insoluble aggregates can be triggered by low pH. Additionally, biophysical measurements of ,2M using NMR have identified residues of the protein that participate in the formation of amyloid fibrils. The crystal structure of monomeric human ,2M determined at pH 5.7 shows that one of its edge ,-strands (strand D) adopts a conformation that differs from other structures of the same protein obtained at higher pH. This alternate ,-strand arrangement lacks a ,-bulge, which may facilitate protein aggregation through intermolecular ,-sheet association. To explore whether the pH change may yield the observed conformational difference, molecular dynamics simulations of ,2M were performed. The effects of pH were modeled by specifying the protonation states of Asp, Glu, and His, as well as the C terminus of the main chain. The bulged conformation of strand D is preferred at medium pH (pH 5,7), whereas at low pH (pH < 4) the straight conformation is observed. Therefore, low pH may stabilize the straight conformation of edge strand D and thus increase the amyloidogenicity of ,2M. [source] Macroscopic and Microscopic Anatomy of the Oviduct in the Sexually Mature Rhea (Rhea americana)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2008R. C. Parizzi Summary The morphological characteristics of the oviduct of 12 sexually mature rheas (Rhea americana) were studied. Only the left oviduct is developed as a long tube with a length of 122 ± 23.1 cm, and is subdivided into infundibulum (15.2 ± 4.0 cm), magnum (63.3 ± 9.4 cm), isthmus (5.6 ± 3.1 cm), uterus (16.0 ± 4.2 cm) and vagina (11.5 ± 1.4 cm). The mucous membrane of the oviduct, as a whole, possesses luminal folds covered by ciliated columnar epithelium with secretory cells. The infundibulum part presents a cranial opening with thin and long fimbriae with few tubular glands in caudal tubular portion. In the magnum, the largest portion of the oviduct, the folds are thicker and are filled with tubular glands. The isthmus is short and presents less bulky folds and a few tubular glands. A bag-shaped uterus in the cranial area shows thin folds, and in the caudal region (shell gland) more ramified folds with few tubular glands. The vagina has long luminal folds and a thick muscular tunic; no glands with sperm-storage characteristics have been observed. In conclusion, the oviduct in sexually mature rhea has morphological similarities with the other species of birds already described; however it presents its own characteristics to produce a big egg. [source] A Quantitative Study of the Neural Changes Underlying Pyloric Stenosis in DogsANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2002R. M. Abel Summary This study aimed to quantify the neural changes in congenital pyloric stenosis in dogs and to study the comparative anatomy between this condition in dogs and that in infantile hypertrophic pyloric stenosis. Eight specimens from the pylorus of dogs with pyloric stenosis and six control specimens were examined using conventional histology and immunohistochemistry for a range of neural antigens. The changes in the proportion of nerves immunoreactive for each antigen were quantified and analysed statistically. The morphology of the nerves in the diseased dogs was similar to that in controls. Only vasoactive intestinal peptide was reduced in expression in dogs (median proportion in control dogs 0.57, in diseased dogs 0.17; P = 0.065). This study demonstrates both morphological similarities and significant differences between closely related conditions in dogs, humans and other species. [source] Molecular evidence for the hybrid origin of a new endemic species of Stylosanthes Sw. (Fabaceae) from the Mexican Yucatán PeninsulaBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2002JACQUELINE VANDER STAPPEN Stylosanthes aff. calcicola is a formally undescribed tetraploid species from the Mexican Yucatán Peninsula, showing morphological similarities to the diploid species S. calcicola, but distinct in a number of characters. We used uni- and biparentally inherited molecular markers to infer the hybrid origin of this species in relation to known diploid species of Stylosanthes. Molecular characterization was based on length and/or DNA sequence variation of nuclear sequence-tagged site (STS) markers, the internal transcribed spacer (ITS) region of nuclear rDNA and the trnL intron of chloroplast DNA (cpDNA). Stylosanthes aff. calcicola contains a distinct cpDNA haplotype and nuclear DNA fragment, with closest relationship to the diploid species S. calcicola. In contrast, the DNA sequences of two nuclear loci reveal a closer relationship to the diploid species S. angustifolia, S. hispida, S. humilis, S. leiocarpa and S. viscosa. The majority of the STS markers showed additivity of PCR fragments in S. aff. calcicola, representing the combination of two genetically different genomes. We postulate that S. aff. calcicola is a distinct species of allotetraploid origin that appears to have originated once from hybridization between two divergent genomes, of which the maternal and paternal parent are closely related to, or derived from, a member of the lineages represented by S. calcicola and S. viscosa, respectively. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society, 140, 1,13. [source] A new specimen of Helicoprion Karpinsky, 1899 from Kazakhstanian Cisurals and a new reconstruction of its tooth whorl position and functionACTA ZOOLOGICA, Issue 2009O. A. Lebedev Abstract A new Helicoprion bessonowi Karpinsky, 1899 (Chondrichthyes, Eugeneodontiformes) specimen from the Artinskian of Kazakhstan is described. This is the southernmost occurrence of this species in the Cisurals area. Its presence suggests a biogeographical link for this species between the Cisurals and Japan. Residue obtained from chemical preparation of the sample included numerous scales and several teeth, which are tentatively assigned to Helicoprion. This assumption is based upon morphological similarity of the scales to those known in other eugeneodontiforms. Campodus -like teeth might be part of the lateral dentition of Helicoprion. A new reconstruction of the interaction of the lower tooth whorl with the upper jaw dentition is suggested and its function is discussed. It is proposed that there was no symphysial whorl in the upper jaw but its role was played by a rigid cover formed by a series of small teeth at the palatoquadrates. Microscopic study of the tooth crown surface revealed scratch marks, which might have resulted from pressing the food object against the upper jaw. Using extant odontocetans as an ecological model led to a conclusion that helicoprionids most likely fed on cephalopods and to some extent on fish. This assumption is based upon the concentration of functional dentition in the area of the lower jaw symphysis in both groups of animals. [source] Communal spawning of brook and river lampreys (Lampetra planeri and L. fluviatilis) is common in the Oir River (France)ECOLOGY OF FRESHWATER FISH, Issue 3 2010E. Lasne Lasne E, Sabatié M-R, Evanno G. Communal spawning of brook and river lampreys (Lampetra planeri and L. fluviatilis) is common in the Oir River (France). Ecology of Freshwater Fish 2010: 19: 323,325. © 2010 John Wiley & Sons A/S Abstract,,, The taxonomic status of river Lampreys (Lampetra fluviatilis) and brook lampreys (L. planeri) has been repeatedly questioned due to the high morphological similarity of these species. Here, we report a high frequency (54%) of communal spawning involving both species in the Lampetra redds of a French coastal river. These observations suggest that reproductive isolation between the two species may not be as strong as previously supposed. [source] Post-embryonic development of the Furongian (late Cambrian) trilobite Tsinania canens: implications for life mode and phylogenyEVOLUTION AND DEVELOPMENT, Issue 4 2009Tae-yoon Park SUMMARY The current concept of the order Asaphida was proposed to accommodate some Cambrian and Ordovician trilobite clades that are characterized by the possession of a ventral median suture. The family Tsinaniidae was recently suggested to be a member of the order Asaphida on the basis of its close morphological similarity to Asaphidae. Postembryonic development of the tsinaniid trilobite, Tsinania canens, from the Furongian (late Cambrian) Hwajeol Formation of Korea, reveals that this trilobite had an adult-like protaspis. Notable morphological changes with growth comprise the effacement of dorsal furrows, sudden degeneration of pygidial spines, regression of genal spines, and loss of a triangular rostral plate to form a ventral median suture. Programmed cell death may be responsible for degenerating the pygidial and genal spines during ontogeny. Morphological changes with growth, such as the loss of pygidial spines, modification of pleural tips, and effacement of dorsal furrows, suggest that T. canens changed its life mode during ontogeny from benthic crawling to infaunal. The protaspid morphology and the immature morphology of T. canens retaining genal and pygidial spines suggest that tsinaniids bear a close affinity to leiostegioids of the order Corynexochida. Accordingly, development of a ventral median suture in T. canens demonstrates that the ventral median suture could have evolved polyphyletically, and thus the current concept of the order Asaphida needs to be revised. [source] Garnet-filled trails associated with carbonaceous matter mimicking microbial filaments in Archean basaltGEOBIOLOGY, Issue 4 2009K. LEPOT The study of the earliest traces of life on Earth can be complicated by abiotically formed biomorphs. We report here the finding of clustered micrometer-sized filaments of iron- and calcium-rich garnets associated with carbonaceous matter in an agate amygdale from a 2.7-billion-year-old basalt of the Maddina Formation, Western Australia. The distribution of carbonaceous matter and the mineral phases composing the filaments were analyzed using a combination of confocal laser scanning microscopy, laser-Raman micro-spectroscopy, focused ion beam sectioning and transmission electron microscopy. The results allow consideration of possible biogenic and abiotic processes that produced the filamentous structures. The filaments have a range of sizes, morphologies and distributions similar to those of certain modern iron-mineralized filamentous bacteria and some ancient filamentous structures interpreted as microfossils. They also share a high morphological similarity with tubular structures produced by microbial boring activity. However, the microstructures and the distribution of carbonaceous matter are more suggestive of an abiotic origin for the filaments. They are characteristic features of trails produced by the displacement of inclusions associated with local dissolution of their silica matrix. Organic compounds found in kerogen or bitumen inclusions may have contributed significantly to the dissolution of the quartz (or silica gel) matrix driving filamentous growth. Discriminating the products of such abiotic organic-mediated processes from filamentous microfossils or microbial borings is important to the interpretation of the scarce Precambrian fossil record and requires investigation down to the nanoscale. [source] GEITLERINEMA SPECIES (OSCILLATORIALES, CYANOBACTERIA) REVEALED BY CELLULAR MORPHOLOGY, ULTRASTRUCTURE, AND DNA SEQUENCING,JOURNAL OF PHYCOLOGY, Issue 3 2009Maria Do Carmo Bittencourt-Oliveira Geitlerinema amphibium (C. Agardh ex Gomont) Anagn. and G. unigranulatum (Rama N. Singh) Komárek et M. T. P. Azevedo are morphologically close species with characteristics frequently overlapping. Ten strains of Geitlerinema (six of G. amphibium and four of G. unigranulatum) were analyzed by DNA sequencing and transmission electronic and optical microscopy. Among the investigated strains, the two species were not separated with respect to cellular dimensions, and cellular width was the most varying characteristic. The number and localization of granules, as well as other ultrastructural characteristics, did not provide a means to discriminate between the two species. The two species were not separated either by geography or environment. These results were further corroborated by the analysis of the cpcB- cpcA intergenic spacer (PC-IGS) sequences. Given the fact that morphology is very uniform, plus the coexistence of these populations in the same habitat, it would be nearly impossible to distinguish between them in nature. On the other hand, two of the analyzed strains were distinct from all others based on the PC-IGS sequences, in spite of their morphological similarity. PC-IGS sequences indicate that these two strains could be a different species of Geitlerinema. Using morphology, cell ultrastructure, and PC-IGS sequences, it is not possible to distinguish G. amphibium and G. unigranulatum. Therefore, they should be treated as one species, G. unigranulatum as a synonym of G. amphibium. [source] Phenotypical characterization of indigenous freshwater crayfish populationsJOURNAL OF ZOOLOGY, Issue 2 2007D. Sint Abstract The morphology of an animal is known to reflect both genetic variation and adaptation to the environment. Thus, phenotypic criteria have been used to characterize indigenous crayfish populations. Twenty-one morphometric parameters were measured on crayfish from 25 waterbodies in the Austrian and Italian parts of Tyrol. They were analysed with hierarchical cluster analysis to obtain the population structure based on morphological similarity between and within the freshwater crayfish species Astacus astacus (noble crayfish), Austropotamobius torrentium (stone crayfish) and Austropotamobius pallipes (white-clawed crayfish). Furthermore, a stepwise discriminant analysis was applied to the morphometric data to test their differentiating power between populations. Both analyses resulted in a clear differentiation of species and populations, and reflected geographic separations. Thus, the developed morphometric methods were shown to be applicable to characterize the phenotype in freshwater crayfish and seem appropriate to be used for stock identification and the effective characterization of management units in decapod crustaceans. [source] Optical touch pointer for fluorescence guided glioblastoma resection using 5-aminolevulinic acid,LASERS IN SURGERY AND MEDICINE, Issue 1 2010Neda Haj-Hosseini MS Abstract Background and Objective Total tumor resection in patients with glioblastoma multiforme (GBM) is difficult to achieve due to the tumor's infiltrative way of growing and morphological similarity to the surrounding functioning brain tissue. The diagnosis is usually subjectively performed using a surgical microscope. The objective of this study was to develop and evaluate a hand-held optical touch pointer using a fluorescence spectroscopy system to quantitatively distinguish healthy from malignant brain tissue intraoperatively. Study Design/Materials and Methods A fluorescence spectroscopy system with pulsed modulation was designed considering optimum energy delivery to the tissue, minimal photobleaching of PpIX and omission of the ambient light background in the operating room (OR). 5-Aminolevulinic acid (5-ALA) of 5,mg/kg body weight was given to the patients with a presumed GBM prior to surgery. During the surgery a laser pulse at 405,nm was delivered to the tissue. PpIX in glioblastoma tumor cells assigned with peaks at 635 and 704,nm was detected using a fiber optical probe. Results/Conclusion By using the pulsed fluorescence spectroscopy, PpIX fluorescence is quantitatively detected in the GBM. An effective suppression of low power lamp background from the recorded spectra in addition to a significant reduction of high power surgical lights is achieved. Lasers Surg. Med. 42:9,14, 2010. © 2010 Wiley-Liss, Inc. [source] Identification and characterization of 10 microsatellite primers for the calanoid freshwater copepods Eudiaptomus gracilis and E. graciloides using enriched genomic librariesMOLECULAR ECOLOGY RESOURCES, Issue 3 2004MARTINA ZELLER Abstract The calanoid copepods Eudiaptomus gracilis and Eudiaptomus graciloides are widespread among European lakes. We constructed enriched genomic libraries for both species in order to isolate and characterise microsatellite markers. The obtained 7 polymorphic microsatellite-loci for E. gracilis and 3 for E. graciloides are the first for any freshwater copepod. They display an expected heterozygosity ranging from 0.60 to 0.96 and 0.63 to 0.94 and observed heterozygosity ranging from 0.53 to 0.87 and 0.57 to 0.87, respectively. We were not able to cross-amplify the isolated loci across species, indicating long divergence among both congeneric species despite morphological similarity. [source] IDENTIFICATION OF MOLECULAR MARKERS IN DCIS RECURRENCEPATHOLOGY INTERNATIONAL, Issue 12 2001Provenzano E Background: DCIS represents preinvasive malignant change. With screening mammography DCIS has become a common entity. Its natural history is poorly understood and treatment remains controversial. Using a retrospective population based cohort, we have identified histological and molecular variables predictive of recurrence. Methods: All cases of DCIS reported in Victoria between 1988 and 1992 were entered into the Victorian Cancer Registry. In Situ and Small Cancer Register (ISSIBCR) and followed up annually regarding treatment, the event of recurrence and its nature and location. From this register a cohort of 66 DCIS lesions with subsequent recurrence as in situ or invasive disease were studied histologically, immunohistochemically and with CGH-based genetic analyses comparing them to a nested randomized control group of DCIS without recurrence matched for patient age and year of diagnosis. Recurrences have been analysed by the same techniques to compare them to the primary lesion. Results: 13 histological features were evaluated and lesion size, nuclear pleomorphism, cellular polarity, micropapillary architecture and central necrosis were all significant predictors of recurrence (p < 0.05). Immunohistochemistry showed p21 overexpression, bcl2 negativity and ERBB2 positivity to be markers of recurrence. In the case of ERBB2, positivity was a predictor of recurrence even when its overexpression was focal. Primary and recurrent DCIS lesions had similar morphological appearances, and grade of primary DCIS correlated with grade of subsequent invasive cancer. This morphological similarity was paralleled by similar protein expression and genomic changes in both in situ and invasive recurrences. Conclusion: We have identified histological and immunohistochemical markers of recurrence in DCIS, and shown similarities in morphology, protein expression and genetic changes between primary DCIS and its recurrence. [source] Morphology and Phylogenetic Position of Eucomonympha imla (Parabasalia: Hypermastigida)THE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 4 2007KEVIN J. CARPENTER ABSTRACT. Eucomonympha imla is a hypermastigote parabasalian found in the gut of the wood-feeding cockroach Cryptocercus punctulatus. It has received little attention since its original description in 1934 as the type species of the genus Eucomonympha and the family Eucomonymphidae. We used light and scanning electron microscopy to characterize surface morphology and organelles, with particular attention to the form of the rostrum, operculum, nucleus, and parabasals. Two previously unrecognized groups of bacterial ectobionts were observed,spirochetes that associate with the flagella and one or more types of rod-shaped bacteria that adhere to the cell surface. The small subunit rRNA (SSU rRNA) sequence was determined from manually isolated cells, and phylogenetic analyses place E. imla in a strongly supported clade with the genera Teranympha and Pseudotrichonympha and three sequences from formally undescribed termite symbionts provisionally assigned to Eucomonympha. Unexpectedly, the Eucomonympha isolates from termites are more closely related to Teranympha than to the type species, suggesting these should not be classified as species of Eucomonympha, despite their morphological similarity to E. imla. Eucomonymphidae fall within a strongly supported Trichonymphida (also including Hoplonymphidae, Trichonymphidae, and Staurojoeninidae), but this clade branches separately from other hypermastigote groups (lophomonads and spirotrichonymphids), suggesting that hypermastigotes are polyphyletic. [source] Deep genetic divergences among morphologically similar and parapatric Skistodiaptomus (Copepoda: Calanoida: Diaptomidae) challenge the hypothesis of Pleistocene speciationBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009RYAN A. THUM We used mitochondrial [cytochrome c oxidase subunit I (CO I), cytochrome b, and 16S] and nuclear [internal transcribed spacer (ITS) phylogenies of Skistodiaptomus copepods to test hypotheses of Pleistocene divergence and speciation within the genus. Mitochondrial (mt)DNA sequence divergences do not support hypotheses for Pleistocene speciation and instead suggest much more ancient speciation events in the genus. Skistodiaptomus oregonensis and Skistodiaptomus pygmaeus (i.e. two morphologically similar and parapatric species) exhibited uncorrected mtDNA sequence divergences exceeding 20%. Similarly, we identified three divergent clades of Skistodiaptomus pallidus that exhibited mtDNA sequence divergences exceeding 15%, suggesting that even intraspecific divergence within this morphospecies predates the Pleistocene. We found clear evidence of CO I pseudogenes in S. pygmaeus, but their presence did not lead to significant overestimates of sequence divergences for this gene. Substitution saturation and strong purifying selection have most likely led to underestimates of sequence divergences and divergence times among Skistodiaptomus. The widespread phenomenon of morphological stasis among genetically divergent copepod groups indicates that speciation often occurs with little or no morphological change. Instead, morphological evolution may occur idiosyncratically after speciation and create discordant patterns of morphological similarity, shared ancestry and divergence time. Cryptic species complexes are therefore common in copepods, and morphological species concepts underestimate their true species diversity. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 150,165. [source] | |||||||||||||||||||||||||||||||