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Germ
Kinds of Germ Terms modified by Germ Selected AbstractsDilaceration of maxillary central incisor: a literature reviewDENTAL TRAUMATOLOGY, Issue 5 2010Nikolaos Topouzelis In early developmental stages, the permanent tooth germ of the maxillary incisor is situated palatally and superiorly to the apex of the primary incisor and gradually changes direction in a labial direction with its crown coming closer to the resorbing primary root. For reasons of this close relationship between the permanent tooth germ and the apex of the primary incisor, it is believed that an acute trauma to the primary predecessor can cause dilaceration of the long axis of the permanent successor. Clinically, dilaceration can be revealed by palpation high in the labial sulcus or in the hard palate, while its radiographic view is characteristic. The therapeutic approach to the dilacerated maxillary central incisors has to be carefully planned and needs the cooperation of several specialities to attain the final objective. [source] Odontoma-like malformation in a permanent maxillary central incisor subsequent to trauma to the incisor predecessorDENTAL TRAUMATOLOGY, Issue 5 2005Paulo Nelson-Filho Abstract,,, This report describes a case of a patient (1 year and 8 months old) with traumatic avulsion of the maxillary right primary central incisor and morphological changes in the germ of the permanent successor. One year after the trauma, an odontoma-like malformation developed. This malformation was removed 6 years after trauma and orthodontic treatment was started. Clinical follow-up and periodic radiographs are necessary after traumatic avulsion of primary teeth to monitor possible sequelae in the permanent successor. An odontoma-like malformation requires a multidisciplinary approach. [source] Identification of germ plasm-associated transcripts by microarray analysis of Xenopus vegetal cortex RNADEVELOPMENTAL DYNAMICS, Issue 6 2010Tawny N. Cuykendall Abstract RNA localization is a common mechanism for regulating cell structure and function. Localized RNAs in Xenopus oocytes are critical for early development, including germline specification by the germ plasm. Despite the importance of these localized RNAs, only approximately 25 have been identified and fewer are functionally characterized. Using microarrays, we identified a large set of localized RNAs from the vegetal cortex. Overall, our results indicate a minimum of 275 localized RNAs in oocytes, or 2,3% of maternal transcripts, which are in general agreement with previous findings. We further validated vegetal localization for 24 candidates and further characterized three genes expressed in the germ plasm. We identified novel germ plasm expression for reticulon 3.1, exd2 (a novel exonuclease-domain encoding gene), and a putative noncoding RNA. Further analysis of these and other localized RNAs will likely identify new functions of germ plasm and facilitate the identification of cis -acting RNA localization elements. Developmental Dynamics 239:1838,1848, 2010. © 2010 Wiley-Liss, Inc. [source] Expression survey of genes critical for tooth development in the human embryonic tooth germDEVELOPMENTAL DYNAMICS, Issue 5 2007Dahe Lin Abstract In the developing murine tooth, the expression patterns of numerous regulatory genes have been examined and their roles have begun to be revealed. To unveil the molecular mechanisms that regulate human tooth morphogenesis, we examined the expression patterns of several regulatory genes, including BMP4, FGF8, MSX1, PAX9, PITX2, and SHOX2, and compared them with that found in mice. All of these genes are known to play critical roles in murine tooth development. Our results show that these genes exhibit basically similar expression patterns in the human tooth germ compared with that in the mouse. However, slightly different expression patterns were also observed for some of the genes at certain stages. For example, MSX1 expression was detected in the inner enamel epithelium in addition to the dental mesenchyme at the bell stage of the human tooth. Moreover, FGF8 expression remained in the dental epithelium at the cap stage, while PAX9 and SHOX2 expression was detected in both dental epithelium and mesenchyme of the human tooth germ. Our results indicate that, although slight differences exist in the gene expression patterns, the human and mouse teeth not only share considerable homology in odontogenesis but also use similar underlying molecular networks. Developmental Dynamics 236:1307,1312, 2007. © 2007 Wiley-Liss, Inc. [source] Glucose-responsive insulin-producing cells from stem cellsDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 6 2002David J. Kaczorowski Abstract Recent success with immunosuppression following islet cell transplantation offers hope that a cell transplantation treatment for type 1 (juvenile) diabetes may be possible if sufficient quantities of safe and effective cells can be produced. For the treatment of type 1 diabetes, the two therapeutically essential functions are the ability to monitor blood glucose levels and the production of corresponding and sufficient levels of mature insulin to maintain glycemic control. Stem cells can replicate themselves and produce cells that take on more specialized functions. If a source of stem cells capable of yielding glucose-responsive insulin-producing (GRIP) cells can be identified, then transplantation-based treatment for type 1 diabetes may become widely available. Currently, stem cells from embryonic and adult sources are being investigated for their ability to proliferate and differentiate into cells with GRIP function. Human embryonic pluripotent stem cells, commonly referred to as embryonic stem (ES) cells and embryonic germ (EG) cells, have received significant attention owing to their broad capacity to differentiate and ability to proliferate well in culture. Their application to diabetes research is of particular promise, as it has been demonstrated that mouse ES cells are capable of producing cells able to normalize glucose levels of diabetic mice, and human ES cells can differentiate into cells capable of insulin production. Cells with GRIP function have also been derived from stem cells residing in adult organisms, here referred to as endogenous stem cell sources. Independent of source, stem cells capable of producing cells with GRIP function may provide a widely available cell transplantation treatment for type 1 diabetes. Copyright © 2002 John Wiley & Sons, Ltd. [source] Characterization of hydroxyaromatic compounds in vegetable oils by capillary electrophoresis with direct injection in an oil-miscible KOH/propanol/methanol mediumELECTROPHORESIS, Issue 17 2005Carla R. B. Mendonça Abstract The separation of hydroxyaromatic compounds in vegetable oils, including synthetic antioxidants (3- tert -butyl-4-hydroxyanisol and 2,6-di- tert -butyl-4-hydroxytoluene), E-vitamers and other natural oil components, by nonaqueous capillary electrophoresis in an oil-miscible background electrolyte (BGE) was investigated. The BGE contained 40,mM KOH in a methanol/1-propanol (PrOH) mixture (15:85 v/v). The oil samples were 1:1 diluted with PrOH and directly injected in the capillary. Under negative polarity (cathode at the injection end), the anionic solutes moved faster than the electroosmotic flow, being well-resolved among them and from the triacylglycerols. Using virgin palm, extra virgin olive, wheat germ, virgin soybean and other oils, the capability of the procedure to quickly yield a characteristic profile of the biophenols present in the sample was demonstrated. The , -, (,,+,,)- (as unresolved pair) and , -tocopherols of a soybean oil sample were quantified. [source] An evolutionary view on tooth development and replacement in wild Atlantic salmon (Salmo salar L.)EVOLUTION AND DEVELOPMENT, Issue 1 2008A. Huysseune SUMMARY To gain an insight into the evolution of tooth replacement mechanisms, we studied the development of first-generation and replacement teeth on the dentary of wild Atlantic salmon (Salmo salar L.), a protacanthopterygian teleost, using serially sectioned heads of early posthatching stages as well as adults. First-generation teeth develop within the oral epithelium. The anlage of the replacement tooth is first seen as a placode-like thickening of the outer dental epithelium of the predecessor, at its lingual and caudal side. Ongoing development of the replacement tooth germ is characterized by the elaboration of a population of epithelial cells, termed here the middle dental epithelium, apposed to the inner dental epithelium on the lingual side of the tooth germ. Before the formation of the new successor, a single-layered outer dental epithelium segregates from the middle dental epithelium. The dental organs of the predecessor and the successor remain broadly interconnected. The absence of a discrete successional dental lamina in salmon stands in sharp contrast to what is observed in other teleosts, even those that share with salmon the extraosseous formation of replacement teeth. The mode of tooth replacement in Atlantic salmon displays several characters similar to those observed in the shark Squalus acanthias. To interpret similarities in tooth replacement between Atlantic salmon and chondrichthyans as a case of convergence, or to see them as a result of a heterochronic shift, requires knowledge on the replacement process in more basal actinopterygian lineages. The possibility that the middle dental epithelium functionally substitutes for a successional lamina, and could be a source of stem cells, whose descendants subsequently contribute to the placode of the new replacement tooth, needs to be explored. [source] Alu-DNA repeat-binding protein p68 is a part of Alu-RNA containing ,-RNPFEBS JOURNAL, Issue 8 2000Dmitry V. Lukyanov An Alu-DNA repeat-binding protein with a molecular mass of 68 kDa (p68) is identified in the somatic human cell nucleoplasm. Gel mobility shift assay (GMSA), South-western blotting and affinity purification on DNA attached to the carrier were used in the identification. GMSA revealed multiple complexes with the exponential dependence of their relative mobility. A narrow binding site of the p68 was revealed using synthetic oligonucleotides. It is located between the A-box and B-box of the RNA polymerase III promoter and is identical to that reported for the Alu-binding protein from human spermatozoids. The same narrow binding site, the similarity of the isolation procedure from germ and somatic cells, and similar binding properties and molecular masses suggest homology of the two proteins. Antibodies raised against Alu-protein complexes led to hypershift of the complexes in GMSA and stained p68 in active fractions in human spermatozoids and in Alu-RNA-containing ,-RNP particles. Immunofluorescence of a HeLa cell monolayer revealed an intranuclear dot pattern with the dots corresponding to euchromatin areas and some dots located at the cell periphery in the cytoplasm. ,-RNP particles bound Alu-DNA in vitro and contained p68 as shown using the immunogold procedure. Alu-DNA binding activity was revealed in cytoplasm as well as in nucleoplasm. The possible nature of the main Alu-DNA binding protein and its involvement in the particle structure are discussed. [source] Highlighted article: "E(nos)/cg4699 is required for nanos function in the female germ line of Drosophila" by Yu, Song and WhartonGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 3 2010Sally A. Moody Editor in Chief No abstract is available for this article. [source] Molecular cloning, characterization, expression pattern and cellular distribution of an ovarian lipophorin receptor in the cockroach, Leucophaea maderaeINSECT MOLECULAR BIOLOGY, Issue 3 2009M. Tufail Abstract A cDNA that encodes a lipophorin receptor (LpR) with a predicted structure similar to that of the low density lipoprotein receptor (LDLR) gene superfamily was cloned from ovaries of the cockroach, Leucophaea maderae (Lem) and characterized. This is the first LpR sequenced from the order Dictyoptera. The cDNA has a length of 3362 bp coding for an 888-residue mature protein with a predicted molecular mass of ~99.14 kDa and a pI value of 4.68. The deduced amino acid sequence showed that the LemLpR harbours eight ligand-binding repeats (LBRs) at the N-terminus similar to the other insect LpRs, and thus resembles vertebrate VLDLRs. In addition to eight tandemly arranged LBRs, the five-domain receptor contains an O -linked sugar region and the classic LDLR internalization signal, FDNPVY. Northern blot analysis revealed the presence of ~4.0 kb ovarian mRNA that was transcribed throughout oogenesis with its peak especially during late previtellogenic and vitellogenic periods (from days 3 to 11). LpR transcript(s) or homologues of LDLRs were also detected in the head, midgut, Malpighian tubules, muscles and in the fat body. RNA in situ hybridization and immunocytochemistry localized the LpR mRNA and protein to germ line-derived cells, the oocytes, and revealed that LpR gene transcription and translation starts very early during oocyte differentiation in the germarium. LpR protein was evenly distributed throughout the cytoplasm during previtellogenic periods of oogenesis. However, during vitellogenic stages, the receptor was accumulated mainly in the cortex of the oocyte. Immunoblot analysis probed an ovarian LpR protein of ~115 and 97 kDa under reducing and nonreducing conditions, respectively. The protein signal appeared on day 2, increased every day and was high during vitellogenic periods from day 4 to day 7. Southern blot analysis suggested the presence of a single copy of the LpR gene in the genome of Le. maderae. [source] Transcriptional signatures in response to wheat germ agglutinin and starvation in Drosophila melanogaster larval midgutINSECT MOLECULAR BIOLOGY, Issue 1 2009H.-M. Li Abstract One function of plant lectins such as wheat germ agglutinin is to serve as defences against herbivorous insects. The midgut is one critical site affected by dietary lectins. We observed marked cellular, structural and gene expression changes in the midguts of Drosophila melanogaster third instar larvae that were fed wheat germ agglutinin. Some of these changes were similar to those observed in the midguts of starved D. melanogaster. Dietary wheat germ agglutinin caused shortening, branching, swelling, distortion and in some cases disintegration of the midgut microvilli. Starvation was accompanied primarily by shortening of the microvilli. Microarray analyses revealed that dietary wheat germ agglutinin evoked differential expression of 61 transcripts; seven of these were also differentially expressed in starved D. melanogaster. The differentially transcribed gene clusters in wheat germ agglutinin-fed larvae were associated with (1) cytoskeleton organization; (2) digestive enzymes; (3) detoxification reactions; and (4) energy metabolism. Four possible transcription factor binding motifs were associated with the differentially expressed genes. One of these exhibited substantial similarity to MyoD, a transcription factor binding motif associated with cellular structures in mammals. These results are consistent with the hypothesis that wheat germ agglutinin caused a starvation-like effect and structural changes of midgut cells of D. melanogaster third-instar larvae. [source] Identification of antigenic targets of paraproteins by expression cloning does not support a causal role of chronic antigenic stimulation in the pathogenesis of multiple myeloma and MGUSINTERNATIONAL JOURNAL OF CANCER, Issue 2 2007Klaus-Dieter Preuss Abstract Antigenic targets of monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) paraproteins have been suggested to play an important role as growth stimulators in the pathogenesis of these neoplasms. To identify such targets, we screened cDNA libraries from human testis, lung and breast cancer, bovine and porcine muscle and wheat germ for reactivity with paraproteins in the sera from 115 patients with MGUS and MM. Of >6 × 108 paraprotein,antigen interactions screened, an IgA paraprotein from a female patient bound to sperm-specific cylicin-2, and 3 IgG paraproteins bound to tripeptidyl-peptidase-II (TPP-2), insulin-like growth-factor binding-protein-2 (IGFBP-2) and porcine kinesin. Specificity was confirmed by reverse Western blots using recombinant antigens. The broad spectrum of auto-, allo- and heteroantigens as targets of human paraproteins in patients without signs of chronic antigenic stimulation renders a causal role of the antigenic stimulus in the pathogenesis of MGUS and MM unlikely. © 2007 Wiley-Liss, Inc. [source] Classification and sequelae of arrested eruption of primary molarsINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 1 2008INGER KJÆR Aim., The aim of this study was to classify early arrested eruption of primary molars and to analyse and explain the sequelae for the surrounding alveolar bone and the succeeding premolar. Design., The position of the arrested primary molars in the mandible, the height of the local alveolar bone, and the morphology and location of the succeeding premolar were evaluated on radiographs from 29 children. Results., Four groups of arrest from mild to severe with regards to infra-position were categorized (Groups I,IV). Mean ages at the time of referral decreased from Groups I (8 years, 10 months) to Group IV (5 years, 9 months). Sequelae., (i) Reduction of alveolar bone height (Groups I,III); (ii) delayed maturity of the succeeding premolar (two-thirds of the cases); (iii) malformation of the succeeding premolar (mainly Groups III and IV); and (iv) ectopically located premolar occlusal to the retained molar (Group IV). Conclusions., The deeper in the alveolar process a primary molar is retained, the earlier the disturbance in the eruption has occurred, and the greater is the risk of the permanent tooth germ being malformed and malpositioned. It is estimated that the earliest occurrences of arrested eruption of primary molars supposedly occur before the age of 3. [source] PHYSICAL, CHEMICAL, and THERMAL CHARACTERIZATION of WHEAT FLOUR MILLING COPRODUCTS,,JOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2003Y.S. KIM ABSTRACT Hard red winter (HRW) and hard red spring (HRS) wheat milling coproducts (bran, germ, shorts, and red dog) from three commercial flour mills and the Kansas State University pilot mill were evaluated for differences in physical, chemical, and thermal properties. the ranges of bulk density for bran, germ, and red dog determined at three moisture levels were 146.5 to 205.2 kgm,3, 269.2 to 400.6 kgm,3, and 298.9 to 398.1 kgm,3, respectively. the true density ranking order was: red dog >shorts = germ >bran, independently of the moisture level. Red dog had the smallest geometrical mean diameter with the highest variation (coefficient of variation of 23.8%). There was a significant (P < 0.05) difference among wheat blends and milling flows in the thickness of bran and germ at the same particle separation size. the image analysis study determined that the equivalent projected area diameter of bran at the same separation size was significantly (P < 0.05) larger than that of germ. the ratio between the equivalent projected area diameter and the particle thickness were within ranges of 15.7 to 37.6 for bran and 15.5 to 32.2 for germ particles. the chemical composition (ash, protein, lipids and fiber) ranges were determined for each coproduct. Ranges of thermal conductivity for bran, germ, shorts, and red dog were 0.049 to 0.074, 0.054 to 0.0907, 0.057 to 0.076, and 0.063 to 0.080 W(mK),1, respectively. Specific heat of coproducts, measured with a differential scanning calorimeter, exhibited a wider range [1.08,1.94 kJ(kgK),1] than that observed in whole wheat kernels and wheat flour. the variability observed among the samples was due to the different wheat sources and characteristic milling flows for the flour mills. [source] Accuracy of frozen section in the diagnosis of malignant ovarian tumorJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2004Dittakarn Boriboonhirunsarn Abstract Aim:, To evaluate the diagnostic accuracy of frozen section for histopathologic diagnosis of ovarian tumors. Methods:, A total of 147 surgically removed ovarian tumors were studied. Each ovarian tumor sample was evaluated for histopathologic diagnosis using both frozen and paraffin sections. Interpretation was separate and blinded between each technique. Accuracy, diagnostic values and their 95% confidence intervals (CI) were estimated by comparing the results from both techniques, using paraffin section as a gold standard. Results:, Overall accuracy of frozen section was 89.8% (95% CI 83.4,94.0). Sensitivity was 90.4% (95% CI 78.2,96.4) for malignant, 33.3% (95% CI 6.0,75.9) for borderline, and 93.3% (95% CI 85.4,97.2) for benign tumors. The predictive value was 100% (95% CI 90.6,100) for malignant, 20% (95% CI 3.5,55.8) for borderline, and 92.2% (95% CI 84.1,96.5) for benign tumors. Most false negatives occurred in mucinous and borderline tumors. No benign tumor was misdiagnosed as malignant by frozen section. Accuracy and negative predictive value were significantly lower in epithelial rather than germ and other cell types. Excellent agreement with regard to histologic cell type was observed (Kappa 0.81). Conclusion:, Frozen section appears to be an accurate technique for the histopathologic diagnosis of ovarian tumors. Some limitations were observed among borderline and mucinous tumors; this emphasizes the great value of frozen section in the diagnosis of ovarian tumors. [source] Different distribution of immunocompetent cells in the dentogingival junction during root formation in rat molarsJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2003Hiroshi Tamura The distribution of immunocompetent cells in the dentogingival junction of rat molars during root formation was investigated by immunocytochemistry using antibodies to class II major histocompatibility complex (MHC) molecules (OX6-antibody) and monocyte/macrophage lineage cells (ED1-antibody) as well as by histochemical reaction for periodic acid,Schiff (PAS). Two portions (the junctional epithelium in the mesial gingiva of the first molar, and the interdental gingiva between the first and second molars) were selected for observations. At the eruption stage of the first molar (16,18 days after birth), OX6-positive cells, dendritic or oval in shape, were abundantly distributed in the connective tissue between the oral epithelium and tooth germ. Positive cells with slender cell processes were also found beneath the ameloblast layer. At the commencement stage of the first molar occlusion (24,28 days after birth), numerous OX6-positive cells displaying a dendritic fashion existed preferentially in the mesial gingiva, but were fewer in the interdental gingiva. In contrast, the interdental gingiva showed a denser distribution of ED1-positive cells and PAS-reactive polymorphonuclear leukocytes (PMLs) than the mesial gingiva. At the completion stage of root formation (100,120 days after birth), the OX6-immunopositive cells invaded the deeper position of the mesial gingiva with the downgrowth of the epithelium; they had a considerably higher cell density compared with those in the interdental gingiva where PAS-reactive PMLs persisted. These findings indicated that the immunocompetent cells showed a region-specific distribution and cell density by their roles in immune response. [source] Use of a spouted bed to improve the storage stability of wheat germ followed in paper and polyethlyene packagesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2005Füsun Yöndem-Makasc Abstract Stabilization of wheat germ by heating in a spouted bed for 180,540 s with air at 140,200 °C was studied. The lipase activity decreased by 6,65%. Wheat germ processed at 200 °C for 360 s was ranked highest in sensory evaluation, described as having ,a golden color' and ,nutty flavor', and its lipoxygenase activity had decreased by 91.2%. This product and raw wheat germ were stored in paper, polyethylene and vacuum-packed polyethylene pouches at 5 °C, room temperature (18,26 °C) and 40 °C, and the moisture contents, water activities, free fatty acid contents and peroxide values were followed for 20 weeks. The increases were faster in paper pouches than in the polyethylene ones; vacuum packaging in polyethylene did not bring about significant improvement. The peroxide values of raw samples exceeded 10 meq O2 kg,1 oil after 3,23 days while those of the processed samples stored at room temperature or 5 °C were still less than 10 after 20 weeks. The free fatty acid content and peroxide value changes were expressed by zero order kinetics, resulting in similar activation energies for the raw and processed samples. Copyright © 2005 Society of Chemical Industry [source] Phytate content and phytate degradation by endogenous phytase in pea (Pisum sativum)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2001Mattias Fredrikson Abstract In order to rapidly reduce the content of inositol tri,hexaphosphates in pea flour by action of the endogenous phytase, raw materials as well as incubation conditions have been evaluated. The phytate (inositol hexaphosphate) content was analysed in 27 pea varieties; the influence of storage time and the difference in phytate content between the germ and the cotyledon were determined. Furthermore, degradation of inositol phosphates by the endogenous phytase enzyme was studied in pea flour, germ and cotyledon. To find the maximum phytate degradation, the effects of temperature and pH during pea flour incubation were investigated. The most efficient phytate degradation in pea flour incubation was achieved at pH 7.5 and 45,°C. At this condition an almost complete degradation of phytate and a 66% reduction in the sum of inositol hexa-, penta-, tetra- and triphosphates were reached in 10,h. The storage time of pea seeds or removal of the germ did not have a major effect on the phytate content. Since several inositol pentaphosphate isomers were produced during phytate degradation, it can be concluded that peas contain several phytate-degrading enzymes, or one phytate-degrading enzyme with unspecific initial hydrolysation pattern. © 2001 Society of Chemical Industry. [source] The proximal promoter governs germ cell-specific expression of the mouse glutathione transferase mGstm5 geneMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 4 2009Hironari Dehari To explain the tissue-selective expression patterns of a distinct subclass of glutathione S -transferase (GST), transgenic mice expressing EGFP under control of a 2 kb promoter sequence in the 5,-flanking region of the mGstm5 gene were produced. The intent of the study was to establish whether the promoter itself or whether posttranscriptional mechanisms, particularly at the levels of mRNA translation and stability or protein targeting, based on unique properties of mGSTM5, determine the restricted expression pattern. Indeed, the transgene expression was limited to testis as the reporter was not detected in somatic tissues such as brain, kidney or liver, indicating that the mGstm5 proximal promoter is sufficient to target testis-specific expression of the gene. EGFP expression was also more restricted vis-a-vis the natural mGstm5 gene and exclusively found in germ but not in somatic cells. Real-time quantitative PCR (qPCR) data were consistent with alternate transcription start sites in which the promoter region of the natural mGstm5 gene in somatic cells is part of exon 1 of the germ cell transcript. Thus, the primary transcription start site for mGstm5 is upstream of a TATA box in testis and downstream of this motif in somatic cells. The 5, flanking sequence of the mGstm5 gene imparts germ cell-specific transcription. Mol. Reprod. Dev. 76: 379,388, 2009. © 2008 Wiley-Liss, Inc. [source] Expression of Serpinb6 serpins in germ and somatic cells of mouse gonads,MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 1 2006Yves Charron Abstract The serpin superfamily of serine protease inhibitors is implicated in the regulation of numerous physiological processes. In mice, Spi3/Serpinb6 has a broad tissue distribution. We have investigated the expression of Serpinb6 family members in embryonic and adult gonads. In male and female mice, Spi3/Serpinb6 and NK13/Serpinb6b were expressed in developing gonads and in both somatic and germ cells of adult gonads. By contrast, gonadal expression of Spi3C/Serpinb6c was sexually dimorphic and restricted to male germ cells and female somatic cells. These observations raise the question of the possible role(s) of the Serpinb6 family members in gonad development, gametogenesis, and/or fertilization. Mol. Reprod. Dev. © 2005 Wiley-Liss, Inc. [source] Cytokeratins in epithelia of odontogenic neoplasmsORAL DISEASES, Issue 1 2003MM Crivelini Neoplasms and tumours related to the odontogenic apparatus may be composed only of epithelial tissue or epithelial tissue associated with odontogenic ectomesenchyme. The immunohistochemical detection of different cytokeratins (CKs) polypeptides and vimentin has made it easier to explain the histogenesis of many epithelial diseases. The present study aimed to describe the immunohistochemical expression of cytokeratins 7, 8, 10, 13, 14, 18, 19 and vimentin in the epithelial components of the dental germ and of five types of odontogenic tumours. The results were compared and histogenesis discussed. All cells of the dental germ were positive for CK14, except for the preameloblasts and secreting ameloblasts, in which CK14 was gradually replaced by CK19. CK7 was especially expressed in the cells of the Hertwig root sheath and the stellate reticulum. The dental lamina was the only structure to express CK13. The reduced epithelium of the enamel organ contained CK14 and occasionally CK13. Cells similar to the stellate reticulum, present in the ameloblastoma and in the ameloblastic fibroma, were positive for CK13, which indicates a nature other than that of the stellate reticulum of the normal dental germ. The expression of CK14 and the ultrastructural aspects of the adenomatoid odontogenic tumour probably indicated its origin in the reduced dental epithelium. Calcifying odontogenic epithelial tumour is thought to be composed of primordial cells due to the expression of vimentin. Odontomas exhibited an immunohistochemical profile similar to that of the dental germ. In conclusion, the typical IF of odontogenic epithelium was CK14, while CK8, 10 and 18 were absent. Cytokeratins 13 and 19 labelled squamous differentiation or epithelial cells near the surface epithelium, and CK7 had variable expression. [source] Effect of mandibular distraction osteogenesis on developing molarsORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 4 2007M Kleine-Hakala Structured Abstract Authors,,, Kleine-Hakala M, Hukki J, Hurmerinta K Objective,,, To observe the effect of mandibular distraction osteogenesis (DO) on developing molars. Design,,, Descriptive clinical study. Setting,,, University hospital setting. Seventeen children (mean age 7.6 years) with various syndromes (hemifacial/craniofacial microsomia, Goldenhar syndrome, Treacher Collins syndrome, Nager syndrome and Pyle,Bakwin,Krida syndrome) participated. Experimental variable,,, Severely retrognathic lower jaws were distracted (mean 30 days) with an extraoral bicortically fixed DO device. Outcome measure,,, Consecutive panoramic tomograms were analysed after a mean follow-up period of 3.6 years, range 1,6.9 years. Results,,, The mandibular molars were affected by DO in 13 of the 17 patients which included 18 of 63 mandibular molars studied. Structural changes included root malformations, hindered tooth development and the destruction of tooth follicles. Positional changes such as shifted and tilted teeth were also found. Three injured teeth failed to erupt. These changes were because of splitting of the tooth follicle during the osteotomy (22%), piercing of the tooth follicle by the pin (39%) or migration of tooth germ towards the newly created bone (39%). Fifteen per cent of first molars, 43% of second molars and 31% of third molars were affected during the distraction process. Of all dental injuries, 44% were noticed while the appliance was in place. A further 17% of injuries were noted between 3 months and 1 year postoperatively and 33% during the second postoperative year. Conclusions,,, Although dental injuries are a minor disadvantage compared with the vast benefits offered by DO, focusing on these drawbacks might lead to re-consideration of the type of the device as well as the timing of DO. [source] Crystallization and preliminary X-ray diffraction analysis of protein l -isoaspartyl O -methyltransferase from wheat germACTA CRYSTALLOGRAPHICA SECTION D, Issue 2 2001Michelle D. Amaral Wheat-germ protein l -isoaspartyl O -methyltransferase (WPIMT) can initiate the conversion of l -isoaspartyl residues in a protein or peptide, which accumulate during the aging process in wheat-germ seeds, to normal l -aspartyl groups. The recombinant protein of WPIMT was overexpressed in Escherichia coli and purified to homogeneity. The protein was crystallized in the presence of S -adenosine- l -homocysteine using 2-methyl-2,4-pentanediol. Preliminary X-ray analysis indicated a tetragonal space group P41212 or P43212, with unit-cell parameters a = b = 77.3, c = 152.9,Å for cryofrozen crystals at 90,K. The crystals diffracted to 3.3,Å and contain two molecules per asymmetric unit. [source] Taming the fierce roller: an "enhanced" understanding of cellular differentiation in VolvoxBIOESSAYS, Issue 1 2002Stephen M. Miller Few organisms offer a better opportunity to explore the mechanisms of cellular differentiation, and their origins, than Volvox. Volvox consists of just two cell types, germ and soma, and is the most complex member of a family of green algae that includes unicellular and multicellular relatives. At the heart of the cell-fate determination program of Volvox carteri is the regA gene, which encodes a putative transcriptional repressor that prevents somatic cells from expressing reproductive functions. Stark et al.(1) have dissected the regA gene to determine how its expression is restricted to somatic cells. Their results suggest that regA expression is controlled by multiple enhancers, the most important of which prevents transcription in reproductive cells. While these findings shed light on Volvox development, they also raise a new set of questions about the mechanisms that control the germ,soma dichotomy in this organism. BioEssays 24:3,7, 2002. © 2002 John Wiley & Sons, Inc. [source] Chemopreventive effects of coffee bean and rice constituents on colorectal carcinogenesisBIOFACTORS, Issue 1-4 2000Hideki Mori Abstract Polyphenolic compound chlorogenic acid (CGA) known to be much contained in coffee beans was found to have a regressive effect on induced aberrant crypt foci (ACF) as well as on development of ACF in azoxymethane (AOM)-induced colorectal carcinogenesis in rats. Rice germ and ,-aminobutyric acid-enriched defatted rice germ inhibited AOM-induced ACF formation and colorectal carcinogenesis in rats. Ferulic acid (FA) also known to be contained in coffee beans and rice prevented AOM-induced ACF formation and intestinal carcinogenesis in rats. Both of food factors, coffee and rice may be of benefit to prevention of human colorectal cancers. [source] Treatment of Germinated Wheat to Increase Levels of GABA and IP6 Catalyzed by Endogenous EnzymesBIOTECHNOLOGY PROGRESS, Issue 2 2005Hiroyuki Nagaoka We found that the levels of bioactive products from wheat can be increased dramatically by manipulating germination conditions and taking advantage of the activity of endogenous enzymes. The yield of phytic acid (IP6) from wheat germinated in the presence of high, controlled levels of dissolved oxygen (188 ± 28 mg/100 g wheat) was almost three times greater than that from wheat germinated with no supplemental oxygen (74 ± 10 mg/100 g wheat). The yield of ,-aminobutyric acid (GABA) from wheat germinated in the presence of uncontrolled levels of dissolved oxygen was 18 ± 3 times greater than that from nonsupplemented wheat (1 mg/100 g wheat). The concentration of GABA was much greater in wheat germ than in whole wheat, and the yield of GABA from wheat germ processed with supplemental water (163 ± 7 mg/100 g wheat germ) was notably greater than that from wheat germ processed with no supplemental water (100 ± 2 mg/100 g wheat germ). In contrast, IP6 was more concentrated in wheat bran, and the yield of IP6 from wheat bran processed with supplemental water (3100 ± 12 mg/100 g wheat bran) was notably higher than that from wheat bran processed with no supplemental water (2420 ± 13 mg/100 g wheat bran). We conclude that the large amount of GABA extracted from wheat germ is likely due to high glutamate decarboxylase activity and low aminotransferase activity and that the large amount of IP6 extracted from wheat bran is likely due to high levels of tyrosinase activity. Our findings indicate that bioactive molecules such as GABA and IP6 can be successfully mass-produced by taking advantage of endogenous enzymatic activities. [source] Macroaffinity Ligand-Facilitated Three-Phase Partitioning (MLFTPP) of ,-Amylases Using a Modified AlginateBIOTECHNOLOGY PROGRESS, Issue 2 2003Kalyani Mondal The crude extracts of ,-amylases when mixed with alginate, tert -butyl alcohol, and ammonium sulfate resulted in an interfacial precipitate containing polymer-bound amylase. The precipitate was dissolved in 1 M maltose to recover ,-amylase activity. The recovery of ,-amylases were 74%, 77%, and 92% in the case of Bacillus amyloliquefaciens, wheat germ, and porcine pancreas, respectively. All purified preparations showed a single band on SDS-PAGE. [source] Influence of leptin levels and body weight in survival of children with sepsisACTA PAEDIATRICA, Issue 6 2002A Blanco-Quirós High levels of serum leptin (LPT) were reported in adult patients with sepsis and a protective role was suggested. LPT was determined in sera from 55 children with severe sepsis at admission (0 h), 6, 24 and 48 h. LPT levels were higher at 0 h than at 24 h (2.80 vs 1.61 ng/ml; p= 0.009) and a negative correlation was found with IL-13 (p= 0.009), and granulocyte counts (p= 0.035), but not with other factors. Infants younger than 12 mo of age had higher LPT levels than older infants (5.88 vs 2.38 ng/ml; p= 0.0005). The increase in LPT levels was higher in non-survivor patients than in survivors, with a maximum difference at 24 h (5.30 vs 1.45 ng/ml; p= 0.0042). However, LPT levels were not associated with shock, multiorgan failure or the severity score. Children who died showed higher percentiles of weight than survivors (p= 0.025). A subgroup with higher LPT ( False memory and obsessive,compulsive symptomsDEPRESSION AND ANXIETY, Issue 5 2009Heide Klumpp Ph.D Abstract Background: The memory deficit hypothesis has been used to explain the maintenance of repetitive behavior in individuals with obsessive,compulsive disorder, yet the majority of studies focusing on verbal memory show mixed results. These studies primarily evaluated memory accuracy via the inclusion or omission of previously encountered material, as opposed to false recognition (i.e., the inclusion of erroneous material). We evaluated false memories and memory processes in individuals with obsessive,compulsive washing symptoms (OC), individuals matched on depression and anxiety without OC symptoms (D/A), and in nonanxious individuals (NAC). Methods: Twenty-eight OC, 28 D/A, and 29 NAC individuals read OC-threat relevant, positive, and neutral scenarios and then performed a recognition test. Erroneous recognition of words associated to encoded, but not previously viewed, scenarios were classified as false memories. To evaluate processes underlying memory, participants completed a modified remember/know task to examine whether the OC individuals differed from the other individuals in recollective clarity for false memories of OC-relevant (e.g., germs), positive (e.g., lottery), and neutral (e.g., bread) material. Results: The OC individuals used "know" more than the D/A and NAC individuals for false memories of threat. For veridical memories, the OC individuals used "know" more than the NAC, but not, D/A individuals. Conclusions: The greater reliance on "know" (i.e., feelings of familiarity) in general and false threat memories in particular in individuals with OC symptoms may add to feelings of uncertainty for threat-relevant material, which may contribute to compulsive behavior. Depression and Anxiety, 2009. ©2008 Wiley-Liss, Inc. [source] Chick limbs with mouse teeth: An effective in vivo culture system for tooth germ development and analysisDEVELOPMENTAL DYNAMICS, Issue 1 2003Eiki Koyama Abstract Mouse tooth germ development is currently studied by three main approaches: in wild-type and mutant mouse lines, after transplantation of tooth germs to ectopic sites, and in organ culture. The in vivo approaches are the most physiological but do not provide accessibility to tooth germs for further experimental manipulation. Organ cultures, although readily accessible, do not sustain full tooth germ development and are appropriate for short-term analysis. Thus, we sought to establish a new approach that would combine experimental accessibility with sustained development. We implanted fragments of embryonic day 12 mouse embryo first branchial arch containing early bud stage tooth germs into the lateral mesenchyme of day 4,5 chick embryo wing buds in ovo. Eggs were reincubated, and implanted tissues were examined by histochemistry and in situ hybridization over time. The tooth germs underwent seemingly normal growth, differentiation, and morphogenesis. They reached the cap, bell, and crown stages in approximately 3, 6, and 10 days, respectively, mimicking in a striking manner native temporal patterns. To examine mechanisms regulating tooth germ development, we first implanted tooth germ fragments, microinjected them with neutralizing antibodies to the key signaling molecule Sonic hedgehog (Shh), and examined them over time. Tooth germ development was markedly delayed, as revealed by poor morphogenesis and lack of mature ameloblasts and odontoblasts displaying characteristic traits such as an elongated cell shape, nuclear relocalization, and amelogenin gene expression. These phenotypic changes began to be reversed upon further incubation. The data show that the limb bud represents an effective, experimentally accessible as well as economical system for growth and analysis of developing tooth germs. The inhibitory effects of Shh neutralizing antibody treatment are discussed in relation to roles of this signaling pathway proposed by this and other groups previously. © 2002 Wiley-Liss, Inc. [source]
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