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Total Cell Number (total + cell_number)
Selected AbstractsAnalysis of sub-populations of rapid-cycling Brassica rapa following recurrent bi-directional selection for cotyledon sizePLANT BREEDING, Issue 1 2007N. Tel-Zur Abstract Recurrent selection programmes use one or just a few selection criteria, however other indirect traits may be unpredictably changed in a population. This study was conducted to determine the indirect effects of 10 cycles of bi-directional recurrent selection for cotyledon size in the model system of rapid-cycling Brassica rapa. Eight sub-populations (four large- and four small-cotyledon sizes) were phenotypically and cytologically evaluated. Each sub-population was measured by five phenotypic traits. Ploidy and pollen viability were studied and compared with the initial population. Total weight was significantly different in broad and bottleneck-1 sub-populations. Total cell number exhibited statistically significant differences in broad and bottleneck-1 sub-populations, while cell number per unit area exhibited statistically significant differences in broad, bottleneck-2 and bottleneck-3 sub-populations. Decreases in pollen viability in comparison with the base population were observed in three sub-populations. Among the eight sub-populations studied, the most significant phenotypic differences were observed within broad sub-populations. Based on the above, it is possible that bi-directional recurrent selection for cotyledon size may have been a result of indirect selection for two processes, endoreduplication and cell division. [source] Environment and prednisone interactions in the treatment of recurrent airway obstruction (heaves)EQUINE VETERINARY JOURNAL, Issue 5 2000C. A. Jackson Summary Recurrent airway obstruction (RAO) or heaves is a manifestation of a hypersensitivity to dust, moulds, and spores in the environment of a susceptible horse. Although in the majority of RAO-affected horses, clinical remission can be achieved by keeping horses at pasture to reduce their allergen exposure, this often is not practicable. For this reason, we investigated if changing the environment of a single stall in a 4 stall stable was sufficient to improve lung function and reduce inflammation in RAO-affected horses. In addition, we determined if addition of oral prednisone provided additional benefit. Twelve RAO-susceptible horses were stabled, fed hay, and bedded on straw until they developed airway obstruction. At this point, bedding was changed to wood shavings and they were fed a pelleted diet for 2 weeks. Lung function was measured and bronchoalveolar lavage was performed before and 3, 7, and 14 days after environmental modification. In a crossover design, horses were treated for the 14 days with prednisone tablets (2.2 mg/kg bwt, q. 24 h). Horses then returned to pasture for 30 days. Airway obstruction was greatest before environmental modification. Significant improvement in lung function occurred within 3 days of the change in environment and continued to Day 7. Airway function was best after 30 days at pasture. The clinical response achieved by environmental modification was not significantly improved by addition of oral prednisone. The total number of cells, total neutrophils, and percent neutrophils was greatest before environmental modification. In the absence of prednisone, total and percent neutrophils did not decrease until Day 14 and total cell number until 30 days at pasture. In the presence of prednisone, total cells and total and percent neutrophils decreased by Day 3 and again at pasture. The fact that lung function can be improved within 3 days by environmental management alone emphasises the need for allergen reduction as the cornerstone of treatment of RAO. Although prednisone induced a more rapid reduction in airway inflammation, this was not associated with a more rapid improvement in airway function. [source] Linear-agminated juvenile xanthogranulomasINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 4 2008Despoina Kiorpelidou MD An 8-month-old girl presented with an asymptomatic skin lesion on the right popliteal fossa, which had been present for approximately 6 months. The child had a past medical history of a urinary tract infection at the age of 1 month and had been on daily cotrimoxazole since. There was no history of trauma to the site. Examination revealed a solitary, well-demarcated, plaque-like lesion on the right popliteal fossa, with multiple agminated papules in an almost linear distribution (Fig. 1a). The lesion did not follow Blaschko's lines, but was vertical to them. The plaque was slightly indurated, measuring approximately 4 × 1.5 cm, fixed to the overlying skin but movable over the deeper tissue. The papules were yellowish in color and firm to palpation, showing a positive Darier's sign (Fig. 1b,c). There was no regional adenopathy and no other skin lesions were observed. The physical examination and laboratory investigations were otherwise unremarkable. There was no hepatosplenomegaly, and an ocular examination and chest X-ray were normal. Figure 1. Juvenile xanthogranuloma: agminated nodulopapular lesions on the right popliteal fossa (a) showing positive Darier's sign (b and c; arrows) ,A biopsy from the lesion (Fig. 2a) revealed a dermal infiltrate of histiocytes, some of which were foamy, and admixed Touton-type giant cells, lymphocytes, eosinophils, and mast cells. By immunohistochemistry, the predominant cell population was CD68 (KP-1, MIB-1, and PG-M1, all pursued from Dako) positive, but S-100 protein and CD1a negative (Fig. 2b,e). By Giemsa stain, scattered mast cells (< 5% of the total cell number) were detectable within the lesion. The morphology and immunohistochemistry of the lesion were diagnostic for juvenile xanthogranuloma. Eight months later, the lesion was still present but slightly elongated, proportional to the child's growth, and hyperpigmented. Figure 2. Juvenile xanthogranuloma: histomorphology of skin lesion showing a cell-rich histiocytic dermal infiltrate (a) with immunohistochemical characteristics (b,e) of non-Langerhans dendritic cells (a, hematoxylin and eosin; b, anti-S-100 protein; c, anti-CD-1a; d, e, anti-CD68 monocytic markers MIB-1 and KP-1, respectively; a,e, initial magnification ×40) [source] Fibroblast growth factor-9 inhibits astrocyte differentiation of adult mouse neural progenitor cellsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 10 2009Maggie Lum Abstract Fibroblast growth factor-9 (FGF9) is expressed in the CNS and is reported to be a mitogen for glial cells, to promote neuronal survival, and to retard oligodendrocyte differentiation. Here we examined the effects of FGF9 on the differentiation, survival, and proliferation of adult neural progenitor cells derived from the adult mouse subventricular zone. FGF9 by itself induced neurosphere proliferation, but its effects were modest compared with those of epidermal growth factor and FGF2. When neurospheres were dissociated and plated for differentiation, FGF9 increased total cell number over time in a dose-dependent manner. Ki67 immunostaining and bromodeoxyuridine incorporation indicated that this was at least partially due to the continued presence of proliferative nestin-positive neural progenitor cells and ,III tubulin-positive neuronal precursors. FGF9 also promoted cell survival as indicated by a decreased number of TUNEL-positive cells over time. Assessment of differentiation showed that FGF9 increased neuron generation that reflected the increase in total cell number; however, the percentage of progenitor cells differentiating into neurons was slightly decreased. FGF9 had a modest effect on oligodendrocyte generation, although it appeared to slow the maturation of oligodenrocytes at higher concentrations. The most marked effect on differentiation was an almost total lack of glial fibrillary acidic protein (GFAP)-positive astrocytes up to 7 days following FGF9 addition, indicating that astrocyte differentiation was strongly inhibited. Total inhibition required prolonged treatment, although a 1-hr pulse was sufficient for partial inhibition, and bone morphogenic protein-4 could partially overcome the FGF9 inhibition of astrocyte differentiation. FGF9 therefore has multiple effects on adult neural precursor cell function, enhancing neuronal precursor proliferation and specifically inhibiting GFAP expression. © 2009 Wiley-Liss, Inc. [source] A link between the interleukin-6/Stat3 anti-apoptotic pathway and microRNA-21 in preimplantation mouse embryosMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 9 2009Xing-Hui Shen Signal transducers and activators of transcription-3 (Stat3) plays a central role in interleukin-6 (IL-6)-mediated cell proliferation by inhibiting apoptosis in a variety of cell types. MicroRNA-21 (miRNA-21), a ubiquitous miRNA, acts as an anti-apoptotic factor that seems to be indirectly but strictly linked to Stat3. In order to determine whether the IL-6 induced Stat3 anti-apoptosis pathway is linked with miRNA-21, we first determined the effects of recombinant mouse IL-6 on Stat3 expression, mouse embryo viability, and the mRNA levels of apoptosis related genes and miRNA-21 during mouse embryo development in vitro. Addition of 10 or 100,ng/ml of recombinant IL-6 to the culture medium did not affect the developmental ability of 2-cell stage embryos into blastocysts. However, total cell number was significantly increased and apoptosis was reduced in blastocyst stage embryos cultured in the presence of 100,ng/ml of recombinant IL-6. Furthermore, addition of recombinant IL-6 to the culture medium significantly increased the copy numbers of anti-apoptotic miRNA-21, up-regulated Bcl2l1, and down-regulated casp3. Similarly, the injection of mature miRNA-21 into cells up-regulated Bcl2l1 and down-regulated casp3. These results suggest that the induction of the Stat3 anti-apoptotic pathway by IL-6 is linked to miRNA-21 expression, which possibly results in the regulation of cell apoptosis in early mouse embryo development. Mol. Reprod. Dev. 76: 854,862, 2009. © 2009 Wiley-Liss, Inc. [source] Impact of pro-oxidant agents on the morula-blastocyst transition in bovine embryosMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 3 2005Jean-Magloire Feugang Abstract Exposing day 5 bovine morulae to reactive oxygen species induces a delayed degeneration of some blastocysts on day 8 post-insemination (pi) but without affecting the blastocyst rates. The aim of this study was to characterize the resisting and the degenerating population of blastocysts. The kinetics of degeneration of the embryos exposed to the two pro-oxidant agents: 2,2,-azobis (2-amidinopropane) dihydrochloride (AAPH) and buthionine sulfoximine (BSO) was evaluated using time-lapse cinematography. With both agents the first signs of degeneration appeared at day 7.5 pi but the duration of the degeneration process was shorter in presence of AAPH than BSO (4.2 vs. 12.5 hr, ANOVA, P,<,0.05). The resisting blastocysts derived from morulae with a larger diameter (mean diameter: 161 vs. 154 ,m, ANOVA, P,<,0.05) and showed an earlier cavitation (135 vs. 142 hpi, P,<,0.05) than the degenerating ones. The profile of protein neosynthesis at day 7 was not affected by the treatment. The proportion of male embryos was more important in the resisting than in the degenerating population (70 vs. 55%, ,2, P,<,0.05) especially when the stress was induced by AAPH. The quality of the resisting embryos, measured by the total cell number and the rate of apoptosis, did not seem to be affected when compared to control embryos. In conclusion, resistance to oxidative stress seems related to the kinetics of development and/or the sex of the embryos. Resisting embryos apparently display a quality similar to untreated embryos. Mol. Reprod. Dev. © 2005 Wiley-Liss, Inc. [source] Variations in leaf stomatal density and distribution of 53 vine species in JapanPLANT SPECIES BIOLOGY, Issue 1 2008AI-CHEN TAY Abstract To determine variations in stomatal density and distribution in individual leaves of vine species with different growth/life forms and different habitat types, we quantified and compared leaf-area-based stomatal density, epidermal cell density and stomatal index (percentage of stoma on the epidermis to the total cell number, including epidermal and stomatal cells on the epidermis) of 53 species comprising 19 woody species (lianas) and 34 herbaceous vines growing in Japan. We counted the numbers of stomata on both the adaxial and abaxial leaf surfaces using a light microscope. Stomatal density and distribution on the leaf surfaces varied greatly among species. Most of the creeping herbaceous species had stomata on both the adaxial and abaxial leaf surfaces (amphistomatous); however, lianas had no stomata on the adaxial leaf surface. Species from coastal (probably drier) habitats had greater adaxial to abaxial ratios of stomatal density and stomatal indices compared with species from inland habitats. A positive correlation between stomatal density and epidermal cell density was found on the abaxial/adaxial leaf surfaces of the examined species. This suggests that there is a developmental similarity among vine species in which stomata are developed with differentiation of epidermal cells on the leaf surface. Thus, leaf stomatal density and distribution appear to vary among species with different growth/life forms from different habitats under a developmental constraint of leaf surface in vine plants in Japan. [source] Hypoxia enhances proliferation of mouse embryonic stem cell-derived neural stem cellsBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2010Carlos A.V. Rodrigues Abstract Neural stem (NS) cells can provide a source of material with potential applications for neural drug testing, developmental studies, or novel treatments for neurodegenerative diseases. Herein, the ex vivo expansion of a model system of mouse embryonic stem (mES) cell-derived NS cells was characterized and optimized, cells being cultivated under adherent conditions. Culture was first optimized in terms of initial cell plating density and oxygen concentration, known to strongly influence brain-derived NS cells. To this end, the growth of cells cultured under hypoxic (2%, 5%, and 10% O2) and normoxic (20% O2) conditions was compared. The results showed that 2,5% oxygen, without affecting multipotency, led to fold increase values in total cell number about twice higher than observed under 20% oxygen (20-fold vs. 10-fold, respectively) this effect being more pronounced when cells were plated at low density. With an optimal cell density of 104,cells/cm2, the maximum growth rates were 1.9,day,1 under hypoxia versus 1.7,day,1 under normoxia. Cell division kinetics analysis by flow cytometry based on PKH67 tracking showed that when cultured in hypoxia, cells are at least one divisional generation ahead compared to normoxia. In terms of cell cycle, a larger population in a quiescent G0 phase was observed in normoxic conditions. The optimization of NS cell culture performed here represents an important step toward the generation of a large number of neural cells from a reduced initial population, envisaging the potential application of these cells in multiple settings. Biotechnol. Bioeng. 2010;106: 260,270. © 2009 Wiley Periodicals, Inc. [source] Development and characterization of a tissue engineered pancreatic substitute based on recombinant intestinal endocrine L-cellsBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2009Heather Bara Abstract A tissue engineered pancreatic substitute (TEPS) consisting of insulin-producing cells appropriately designed and encapsulated to support cellular function and prevent interaction with the host may provide physiological blood glucose regulation for the treatment of insulin dependent diabetes (IDD). The performance of agarose-based constructs which contained either a single cell suspension of GLUTag-INS cells, a suspension of pre-aggregated GLUTag-INS spheroids, or GLUTag-INS cells on small intestinal submucosa (SIS), was evaluated in vitro for total cell number, weekly glucose consumption and insulin secretion rates (GCR and ISR), and induced insulin secretion function. The three types of TEPS studied displayed similar number of cells, GCR, and ISR throughout 4 weeks of culture. However, the TEPS, which incorporated SIS as a substrate for the GLUTag-INS cells, was the only type of TEPS tested which was able to retain the induced insulin secretion function of non-encapsulated GLUTag-INS cells. Though improvements in the expression level of GLUTag-INS cells and/or the number of viable cells contained within the TEPS are needed for successful treatment of a murine model of IDD, this study has revealed a potential method for promoting proper cellular function of recombinant L-cells upon incorporation into an implantable three-dimensional TEPS. Biotechnol. Bioeng. 2009;103: 828,834. © 2009 Wiley Periodicals, Inc. [source] Subsurface microbiology and biogeochemistry of a deep, cold-water carbonate mound from the Porcupine Seabight (IODP Expedition 307)ENVIRONMENTAL MICROBIOLOGY, Issue 1 2009Gordon Webster Summary The Porcupine Seabight Challenger Mound is the first carbonate mound to be drilled (,270 m) and analyzed in detail microbiologically and biogeochemically. Two mound sites and a non-mound Reference site were analyzed with a range of molecular techniques [catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH), quantitative PCR (16S rRNA and functional genes, dsrA and mcrA), and 16S rRNA gene PCR-DGGE] to assess prokaryotic diversity, and this was compared with the distribution of total and culturable cell counts, radiotracer activity measurements and geochemistry. There was a significant and active prokaryotic community both within and beneath the carbonate mound. Although total cell numbers at certain depths were lower than the global average for other subseafloor sediments and prokaryotic activities were relatively low (iron and sulfate reduction, acetate oxidation, methanogenesis) they were significantly enhanced compared with the Reference site. In addition, there was some stimulation of prokaryotic activity in the deepest sediments (Miocene, > 10 Ma) including potential for anaerobic oxidation of methane activity below the mound base. Both Bacteria and Archaea were present, with neither dominant, and these were related to sequences commonly found in other subseafloor sediments. With an estimate of some 1600 mounds in the Porcupine Basin alone, carbonate mounds may represent a significant prokaryotic subseafloor habitat. [source] Continuous generation of colitogenic CD4+ T cells in persistent colitisEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 5 2008Takayuki Tomita Abstract Inflammatory bowel diseases take chronic courses due to the expansion of colitogenic CD4+ cells. However, it is unclear whether the persistent disease is driven by continuous reactivation of colitogenic memory CD4+ cells to generate effector CD4+ cells or by continuous generation of effector CD4+ cells from naïve cells. To clarify this issue, we performed a series of sequential adoptive transfers of Ly5.2+ and Ly5.1+ CD4+CD45RBhigh cells into RAG-2,/, mice at different time points. We show here that the secondarily transferred CD4+CD45RBhigh cells can be converted to CD4+CD44highCD62L,IL-7R,high effector-memory T cells even in the presence of pre-existing effector-memory CD4+ cells. Although the total cell numbers of CD4+ cells in established colitic mice were consistently equivalent irrespective of the number of primarily transferred cells, the ratio of primarily and secondarily transferred cells was dependent on the ratio of the transferred cell numbers, but not on the order of the transfer. Of note, we found that primarily transferred CD4+ cells produced significantly lower amounts of IFN-, and IL-17 than CD4+ cells arising from secondary transfer. In conclusion, the continuous generation of colitogenic CD4+ cells that compensate for exhausted CD4+ cells may be one of the mechanisms involved in the persistence of colitis. [source] Effect of macromolecule supplementation during in vitro maturation of goat oocytes on developmental potentialMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 3 2004J.R. Herrick Abstract In vitro maturation (IVM) of goat oocytes with serum-supplemented media results in oocytes with reduced developmental potential. The objective of this study was to develop a defined medium for IVM of goat oocytes that better supports subsequent embryonic development. Cumulus oocyte complexes (COC) were matured for 18,20 hr in: Experiment (1), tissue culture medium 199 (TCM199) with 10% (v/v) goat serum or modified synthetic oviduct fluid maturation medium (mSOFmat) with 2.5, 8.0, or 20.0 mg/ml bovine serum albumin (BSA); Experiment (2), mSOFmat with 4.0, 8.0, 12.0, or 16.0 mg/ml BSA; or Experiment (3), 1.0 mg/ml polyvinyl alcohol (PVA; control), 4.0 mg/ml BSA, 0.5 mg/ml hyaluronate plus 0.5 mM citrate, or hyaluronate, citrate, and BSA. Mature COC were coincubated for 20,22 hr with 12,15,×,106 sperm/ml in modified Brackett and Oliphant (mBO) medium. Embryos were cultured for a total of 7 days in G1/2, and evaluated for cleavage, and blastocyst development, hatching, and total cell numbers. In the first experiment, more (P,<,0.05) blastocysts developed per cleaved embryo following maturation in mSOFmat with 2.5 or 8.0 mg/ml BSA than with 20.0 mg/ml BSA or TCM199 with 10% goat serum. The various concentrations of BSA used in the second experiment did not affect (P,>,0.05) any of the developmental endpoints examined. In the third experiment, developmental potential of oocytes matured with PVA or hyaluronate with citrate was not different (P,>,0.05) from oocytes matured in the presence of BSA. These results demonstrate that developmentally competent goat oocytes can be matured under defined conditions. Mol. Reprod. Dev. 69: 338,346, 2004. © 2004 Wiley-Liss, Inc. [source] Consequences of Nitric Oxide Synthase Inhibition During Bovine Oocyte Maturation on Meiosis and Embryo DevelopmentREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2010KRL Schwarz Contents The importance of nitric oxide synthase (NOS) in bovine oocyte maturation was investigated. Oocytes were in vitro matured with the NOS inhibitor Nw - l -nitro-arginine methyl-ester (10,7, 10,5 and 10,3 m l -NAME) and metaphase II (MII) rates and embryo development and quality were assessed. The effect of l -NAME (10,7 m) during pre-maturation and/or maturation on embryo development and quality was also assessed. l -NAME decreased MII rates (78,82%, p < 0.05) when compared with controls without l -NAME (96%). Cleavage (77,88%, p > 0.05), Day 7 blastocyst rates (34,42%, p > 0.05) and total cell numbers in blastocysts were similar for all groups (146,171 cells, p > 0.05). Day 8 blastocyst TUNEL positive cells (3,4 cells) increased with l -NAME treatment (p < 0.05). For oocytes cultured with l -NAME during pre-maturation and/or maturation, Day 8 blastocyst development (26,34%) and Day 9 hatching rates (15,22%) were similar (p > 0.05) to controls pre-matured and matured without NOS inhibition (33 and 18%, respectively), while total cell numbers (Day 9 hatched blastocysts) increased (264,324 cells, p < 0.05) when compared with the controls (191 cells). TUNEL positive cells increased when NOS was inhibited only during the maturation period (8 cells, p < 0.05) when compared with the other groups (3,4 cells). NO may be involved in meiosis progression to MII and its deficiency during maturation increases apoptosis in embryos produced in vitro. Nitric oxide synthase inhibition during pre-maturation and/or maturation affects embryo quality. [source] | |||||||||||||