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Abnormal Morphology (abnormal + morphology)
Selected AbstractsMORPHOLOGICAL REVERSION OF SPIRULINA (ARTHROSPIRA) PLATENSIS (CYANOPHYTA): FROM LINEAR TO HELICAL,JOURNAL OF PHYCOLOGY, Issue 3 2005Zhi Ping Wang The cyanobacterium Spirulina Turpin is characterized by its regularly coiled trichomes. Under some conditions, its helical filaments can convert to abnormal morphologies, such as irregularly curved and even linear shapes, that had been considered as a permanent degeneration that could not be reversed. However, here we found that the linear filaments of Spirulina platensis Geitler could spontaneously revert to the helical form with the same morphology as the original filaments. Further studies showed that the ultrastructural, physiological, and biochemical characteristics of linear filaments were different from those of the original filaments, whereas they were the same for the reverted and the original filaments. The SDS-PAGE analysis revealed at least four proteins or subunits related to Spirulina morphogenesis: The 21.9-kDa and the 20.3-kDa proteins were highly expressed in the helical filaments, whereas the 52.0-kDa and the 31.8-kDa proteins were highly expressed in the linear filaments. The random amplified polymorphic DNA analysis with 96 random primers showed that the genetic background of the reverted filaments was the same as that of the original filaments but distinct from that of the linear filaments. The results indicated that linear filaments of Spirulina could revert to the original morphology under certain conditions, and their other distinctive traits were regained. [source] Ploidy mosaicism in well-developed nuclear transplants produced by transfer of adult somatic cell nuclei to nonenucleated eggs of medaka (Oryzias latipes)DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 9 2007Elena Kaftanovskaya Chromosomal abnormalities such as ploidy mosaicism have constituted a major obstacle to the successful nuclear transfer of adult somatic cell nuclei in lower vertebrates to date. Euploid mosaicism has been reported previously in well-developed amphibian transplants. Here, we investigated ploidy mosaicisms in well-developed transplants of adult somatic cell nuclei in medaka fish (Oryzias latipes). Donor nuclei from primary cultured cells from the adult caudal fin of a transgenic strain carrying the green fluorescent protein gene (GFP) were transferred to recipient nonenucleated eggs of a wild-type strain to produce 662 transplants. While some of the transplants developed beyond the body formation stage and several hatched, all exhibited varying degrees of abnormal morphology, limited growth and subsequent death. Twenty-one transplants, 19 embryos and two larvae, were selected for chromosomal analysis; all were well-developed 6-day-old or later embryonic stages exhibiting slight morphological abnormalities and the same pattern of GFP expression as that of the donor strain. In addition, all exhibited various levels of euploid mosaicism with haploid-diploid, haploid-triploid or haploid-diploid-triploid chromosome sets. No visible chromosomal abnormalities were observed. Thus, euploid mosaicism similar to that observed in amphibians was confirmed in well-developed nuclear transplants of fish. [source] Saccharomyces cerevisiae Ybr004c and its human homologue are required for addition of the second mannose during glycosylphosphatidylinositol precursor assemblyFEBS JOURNAL, Issue 5 2005Anne-Lise Fabre Addition of the second mannose is the only obvious step in glycosylphosphatidylinositol (GPI) precursor assembly for which a responsible gene has not been discovered. A bioinformatics-based strategy identified the essential Saccharomyces cerevisiae Ybr004c protein as a candidate for the second GPI ,-mannosyltransferase (GPI-MT-II). S. cerevisiae cells depleted of Ybr004cp have weakened cell walls and abnormal morphology, are unable to incorporate [3H]inositol into proteins, and accumulate a GPI intermediate having a single mannose that is likely modified with ethanolamine phosphate. These data indicate that Ybr004cp-depleted yeast cells are defective in second mannose addition to GPIs, and suggest that Ybr004cp is GPI-MT-II or an essential subunit of that enzyme. Ybr004cp homologues are encoded in all sequenced eukaryotic genomes, and are predicted to have 8 transmembrane domains, but show no obvious resemblance to members of established glycosyltransferase families. The human Ybr004cp homologue can substitute for its S. cerevisiae counterpart in vivo. [source] Endodontic and periodontal treatments of a geminated mandibular first premolarINTERNATIONAL ENDODONTIC JOURNAL, Issue 2 2002S. Aryanpour Abstract Aim, To describe a rare case of gemination involving a mandibular first premolar. Summary The complex morphology of geminated teeth renders their endodontic and periodontal management difficult. Root canal and periodontal treatments were performed on a geminated mandibular first premolar with three canals. Clinical examination showed two separated crowns with united roots. Radiographically, two distinct pulp chambers with two joined and a third independent canal were seen. Conventional root canal treatment resulted in complete healing of the apical lesion. However, the occurrence of a vertical fracture led to the extraction of the mesial segment. At the follow-up visit, the distal segment was clinically healthy and continued to satisfy functional demands. Key learning points ,Failure to diagnose the initial crack along a gemination groove resulted in further propagation and finally complete vertical fracture. ,Owing to the abnormal morphology of the crown and the complexity of the root canal system in geminated teeth, treatment protocols require special attention. ,For asymptomatic cases without aesthetic or orthodontic problems and without associated pathosis, routine review and careful maintenance are required. [source] Changes in N -linked sugar chain patterns induced by moderate-to-high expression of the galactosyltransferase I gene in a brain-derived cell line, CG4JOURNAL OF NEUROSCIENCE RESEARCH, Issue 1 2005Krishnakumar N. Menon Abstract Oligosaccharides with biantennae and bisecting N -acetyl glucosamine (GlcNAc) residues attached to the mannose in the ,1-4 trimannosyl core (BA2) are enriched in the brain and considered brain-type sugar chains. We investigated the significance of the interplay between galactosyltransferase I (GalTase I) and BA2 formation in a brain-derived cell line, CG4. Increased GalTase expression in different glial- and neuronal-derived cell lines was accompanied by decreased or undetectable levels of BA2, depending on the level of GalTase expression. Forceful expression of GalTase I in CG4 cells expressing high levels of BA2 and low GalTase activity significantly reduced BA2 levels. In addition, a sixfold increase in an abnormal sugar chain A1(6)G1Fo and a moderate increase in A2G2Fo(6)F were evident. The increased levels of A1(6)G1Fo indicate a diversion or abrogation of the N -linked sugar chain biosynthetic pathway from normal. The accumulation of A1(6)G1Fo and increased A2G2Fo(6)F levels were accompanied by decreased levels of the high mannose-type sugar chains, M5A, M6B, M8A, and M9A. Increased GalTase I expression also led to stunted growth and abnormal morphology of CG4 cells, with increased mortality. Even moderate overexpression of GalTase I thus disrupts the normal biosynthetic pathway of N -linked sugar chains, and high overexpression is fatal to CG4 cells. © 2005 Wiley-Liss, Inc. [source] An in vitro study on reproductive toxicology of Deltamethrin on rat spermatozoaANDROLOGIA, Issue 4 2010F. Ben Abdallah Summary Recent findings indicate that synthetic pyrethroid insecticide may induce toxic manifestations by enhancing the production of reactive oxygen species and disrupting the balance between pro-oxidants and antioxidants as a result of lipid peroxidation (LP) of cell membranes. The aim of the study was to examine the potency of Deltamethrin (Del) to induce oxidative stress response in rat spermatozoa in vitro. Spermatozoa were incubated with different concentrations (0, 10, 50, 100 and 200 ,m) of Del for 3 h at 37 °C. After that, sperm parameters (motility, viability and abnormal morphology), malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) levels were determined. We found that in vitro exposure to Del caused a significant decline of sperm motility and viability and increase of abnormal sperm morphology, MDA, SOD and CAT levels at different concentrations of Del. This study demonstrated that Del caused deterioration in sperm motility and viability, and induction in LP, abnormal morphology of spermatozoa and antioxidants enzyme activities. [source] Milt characteristics of diploid and triploid Atlantic cod (Gadus morhua L.)AQUACULTURE RESEARCH, Issue 10 2009Stefano Peruzzi Abstract The work compares the characteristics of milt produced by diploid and triploid Atlantic cod in terms of sperm motility, density, DNA content, seminal-fluid composition and the ability of sperm to fertilize the eggs. The mean track velocity (VCL) was higher in the sperm of diploid than in the triploid males at 20 s post-activation (p.a.; 124.04 ± 6.91 vs. 113.32 ± 6.32 ,m s,1), but not at 40 s p.a. No differences between ploidies were observed for the remaining sperm-motility descriptors as for spermatozoa density, spermatocrit or seminal fluid's variables like pH, osmolarity, Cl,, Na+, Ca2+ and K+ concentration. Triploid males produced aneuploid sperm cells (average 1.46n, range 1.2,1.6n) and the larvae generated from artificial crossings with diploid females showed abnormal morphology and did not survive to exogenous feeding. Plasma concentration of 11-ketotestosterone in sexually mature diploid and triploid males was similar (5.35 ± 1.54 vs. 4.82 ± 1.15 ng mL,1) and no differences were found in the ability of males of both ploidies to induce spawning when held in tanks with diploid females. The paper provides evidence of gametic sterility of triploid males and examines the use of triploid fish as a management option to address the issues of genetic containment of farmed cod alongside measures for securing present fish-farming technologies. [source] Endodontic management of a fused mandibular third molar and distomolar: A case reportAUSTRALIAN ENDODONTIC JOURNAL, Issue 1 2010Ali Zeylabi dds Abstract Careful management of fused teeth is essential as abnormal morphology can predispose a tooth to caries and periodontal disease. In this paper, a rare case of successful endodontic management of unilateral mandibular third molar fused to a distomolar is reported. Caries was removed from the tooth complex under local anaesthesia. The pulp chambers of the third molar and supernumerary tooth were accessed and the root canals were prepared using rotary instrumentation and copious irrigation with 2.5% sodium hypochlorite. Obturation using the lateral condensation technique with gutta-percha and AH26 sealer was subsequently performed. A 1-year recall showed a good treatment result. [source] PERCUTANEOUS TRANSCATHETER CLOSURE OF PATENT DUCTUS ARTERIOSUS WITH AN AMPLATZER DUCT OCCLUDER USING RETROGRADE GUIDEWIRE-ESTABLISHED FEMORAL ARTERIOVENOUS LOOPCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 5-6 2008Jian-Fa Zhang SUMMARY 1The traditional antegrade wire-guided percutaneous transcatheter approach is not ideal in closing some types of patent ductus arteriosus (PDA) with abnormal morphology. The aim of the present study was to evaluate the efficacy of a retrograde wire-guided transcatheter approach for closure of some types of PDA using the Amplatzer duct occluder (ADO). 2Nineteen patients with abnormal PDA morphology, including a smaller ostium of the side of the pulmonary artery compared with the side of the descending aorta, severe calcification or tortuosity, were included in the present study. In these patients, after the antegrade approach failed to cross a wire from the pulmonary artery via the PDA to the descending aorta, a retrograde guidewire was passed through the PDA in the opposite direction, from the descending aorta to the pulmonary artery, to establish a femoral arteriovenous loop that assisted the deployment of the ADO in all 19 patients. The size of the PDA, as determined by angiography, was 3.1 ± 1.1 mm and the diameter of the ADO selected was 6.5 ± 1.5 mm. 3In 16 cases, systolic murmur disappeared after the procedure. Systolic murmur (less than Grade II) and angiographic residual shunt remained in three cases immediately after the procedure, but disappeared 1 month later. Mean pulmonary arterial pressure decreased from 33 ± 8 to 22 ± 4 mmHg in all 19 patients (P < 0.01). There were no complications during or after the procedure. 4The retrograde wire-guided technique offers an alternative approach to facilitate closure of a PDA that cannot be achieved by traditional antegrade wire-guided methods due to morphological abnormalities in the PDA. [source] | |||||||||||||