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Kinds of Low Percentage Selected AbstractsGeneration and characterization of a novel neural crest marker allele, Inka1-LacZ, reveals a role for Inka1 in mouse neural tube closureDEVELOPMENTAL DYNAMICS, Issue 4 2010Bethany S. Reid Abstract Previous studies identified Inka1 as a gene regulated by AP-2, in the neural crest required for craniofacial morphogenesis in fish and frog. Here, we extend the analysis of Inka1 function and regulation to the mouse by generating a LacZ knock-in allele. Inka1-LacZ allele expression occurs in the cephalic mesenchyme, heart, and paraxial mesoderm prior to E8.5. Subsequently, expression is observed in the migratory neural crest cells and their derivatives. Consistent with expression of Inka1 in tissues of the developing head during neurulation, a low percentage of Inka1,/, mice show exencephaly while the remainder are viable and fertile. Further studies indicate that AP-2, is not required for Inka1 expression in the mouse, and suggest that there is no significant genetic interaction between these two factors during embryogenesis. Together, these data demonstrate that while the expression domain of Inka1 is conserved among vertebrates, its function and regulation are not. Developmental Dynamics 239:1188,1196, 2010. © 2010 Wiley-Liss, Inc. [source] Contrasting infection frequencies of Neotyphodium endophyte in naturalized Italian ryegrass populations in Japanese farmlandsGRASSLAND SCIENCE, Issue 2 2010Masayuki Yamashita Abstract Neotyphodium endophytes often confer benefits to their host grasses and may enhance invasiveness of some grasses. The knowledge of infection frequencies of endophytes among invading weed populations is necessary to understand the relationships between endophyte infection and invasiveness. Here we present data on infection frequencies of Italian ryegrass (Lolium multiflorum Lam.), an important weed in some farmlands in Japan, persisting in contrasting farmlands: a terraced paddy field and a wheat-soybean double-cropped field in the western region of Shizuoka prefecture, Japan. The terraced paddy site is a mosaic of several landscape elements such as paddy fields, levees, fallow and abandoned fields, with a high percentage of non-crop area. Rice (Oryza sativa L.) has been cultivated for more than a decade with no application of chemical fertilizers, pesticides and fungicides. The wheat-soybean field is characterized by the aggregation of large-scaled fields that were originally reconstructed paddy fields, showing a low percentage of non-crop area. Wheat and soybean have been grown as winter and summer crops, respectively, using chemical fertilizers and herbicides. We examined the presence or absence of endophytes in a total of 1200 seeds sampled from the two Italian ryegrass populations. The terraced paddy population exhibited a markedly high infection frequency (91.0%), due possibly to selective feeding of non-infected seeds by insects. In contrast, the wheat-soybean farmland population showed almost no infection (1.1%), whereas the putative source of the invasion in the proximity exhibited a relatively high infection rate (64.4%). Such a micro-scale variation in infection frequencies may be attributable to a loss in endophyte viability within the wheat-soybean field. The findings suggest that endophyte infection frequency may markedly differ among the Italian ryegrass populations even within the same region, presumably depending on the abundance of the seed-eating insects, farmland management regimes and/or environmental conditions such as soil humidity. [source] Palynological, physico-chemical and colour characterization of Moroccan honeys: I. River red gum (Eucalyptus camaldulensis Dehnh) honeyINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2003Anass Terrab Summary The melissopalynological, physico-chemical and colour characteristics of Eucalyptus honeys from Morocco were studied. It is generally accepted that a minimum content of 70% of Eucalyptus pollen is necessary to classify an Eucalyptus honey as unifloral. Twenty-eight physico-chemical and five colour parameters were measured, including the content of sugars and minerals, proline, water content, pH, acidity, hydroxymethylfurfural, diastase activity, ash, electrical conductivity, colour coordinates (L*, a*, b*), chroma (C*ab) and hue angle (hab). Pollen analysis was included, and samples contained a mean of six pollen types (range 2,12). The majority of the samples (75%) contained more than 90%Eucalyptus pollen. The presence of Quercus, Plantago and Thymelaea pollen allows the differentiation of these honeys from those with a different geographical origin. Physico-chemical analysis showed that there was a low percentage of sucrose ( = 0.01%) and trisaccharides. Mineral analysis showed a low percentage of Mg ( = 25.99 ppm) and K ( = 205 ppm), while electrical conductivity ( = 721 ,S cm,1) and diastase activity ( = 39.05 °Gothe) showed medium-high values. The colour parameters lightness (L*) and chroma (C*ab) showed relatively low values. [source] Analysis of peripheral blood T-cell subsets, natural killer cells and serum levels of cytokines in children with Down syndromeINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 4 2010S. Cetiner Summary The objective of this study was to evaluate the relationship between humoral and cell-mediated immune response parameters and impairment of immune functions in children with Down syndrome (DS). The patient group was consisted of cytogenetically documented 32 children with DS. Lymphocyte subsets and natural killer cells were counted by flow-cytometry system. Levels of interleukin (IL)-1,, IL-2, IL-4, IL-6, IL-8, IL-10 and tumour necrosis factor-alpha (TNF-,) were detected by enzyme-linked immunosorbent assay method. Serum IgG, IgM, IgA levels were measured by turbidimetric methods. The percentage of CD8+ lymphocytes and CD56+ cells of patients with DS were significantly higher, whereas CD20+ lymphocytes were lower than that of controls (P < 0.05). The percentage of CD2 and CD4 levels and CD4/CD8 ratio of patients with DS and normal controls were similar (P > 0.05). Levels of IL-4 and IL-10 were significantly increased, but IL-6 and TNF-, levels were decreased in children with DS (P < 0.05). Levels of other studied cytokines between patients with DS and controls were not statistically different (P > 0.05, for all). Serum IgG, IgM and IgA levels were found to be similar between the groups (P > 0.05). It has been known that IL-4 and IL-10 are anti-inflammatory molecules which inhibit the synthesis of proinflammatory cytokines such as IL-6 and TNF-,. In this study, levels of IL-4 and IL-10 were significantly increased, but IL-6 and TNF-, levels were decreased in children with DS. These results may suggest that continuing anti-inflammatory state in DS and this process may explain the cause of recurrent infection of the disease. On the other hand, in contrast to the low percentage of CD20+ cells, high percentage of CD8+ and CD56+ cells were found. Our findings may demonstrate that the cell-mediated and humoral immune system parameters in children with DS were altered according to healthy children. [source] Jordanian baccalaureate nursing students' perception of their learning stylesINTERNATIONAL NURSING REVIEW, Issue 1 2005F. A. Abu-Moghli rn Aim:, The purpose of this descriptive study was to determine Jordanian nursing students' perception of their learning styles. Method:, All nursing students enrolled in four universities offering a baccalaureate degree in nursing at the time of the research project (n = 420) were approached. A structured self-administered questionnaire (Autonomous Learner Index) developed by the researchers was used for data collection. The questionnaire was pilot tested on a sample of nursing students who were not included in the study. The tool was reliable with an alpha coefficient of 0.89. Findings:, The majority of Jordanian nursing students perceived themselves as independent learners. The vast majority of students indicated that they have a desire to learn new things, are curious to learn, and can identify their goal independently. However, a low percentage of students indicated having good study skills, ability to concentrate while studying and using their study time efficiently. The two-tailed t -test indicated no significant differences at alpha 0.05 levels between students' learning preferences and the selected demographic variables. Conclusion:, Based on the study findings, it is suggested that nurse educators should provide positive reinforcement of students' active involvement in the learning process, which will stimulate continued self-direction. Moreover, courses on study skills, writing skills, and literature searching skills should be introduced early in nursing curricula. [source] Peripheral blood stem cell collection in multiple myeloma: A retrospective analysis of 6 years leukapheresis activity in 109 patients treated at the Istituto Nazionale dei Tumori of MilanJOURNAL OF CLINICAL APHERESIS, Issue 4 2009Paola Coluccia Abstract Double autologous stem cell transplantation is the standard treatment in newly diagnosed multiple myeloma (MM) patients younger than 65 years; therefore, optimization of leukapheresis is crucial. We performed a retrospective analysis of 297 leukaphereses comparing semiautomated (V4.7 in 20% of collections) versus automated (V6.0 in 80%) Caridian (COBE) Spectra versions and analyzing the influence of M-protein on the outcome. Both methods gave comparable collection efficiencies (CE%) (53.4% vs. 55.7% in V6.0 and V4.7, respectively) with similar leukapheresis time and processed volume. Harvest volume was higher in V4.7 (P < 0.0001) with similar contamination of red blood cells (RBCs) (P = 0.77) and platelets (P = 0.09) when compared with V6.0. In patients with higher peripheral white blood cells (WBCs), V6.0 with adjusted harvest volume (<700 mL), achieved similar CD34+ CE% (P = 0.39) and better enrichment of nucleated cells (P < 0.0,002) but higher RBCs (P < 0.0,001) and platelets contamination (P = 0.001), when compared with a larger cycle volume in patients with lower WBCs. In hard to mobilize patients, CD34+ CE% was significantly more efficient with V4.7 than V6.0 (P < 0.0,001). CD34+ CE% was unaffected by serologic M-protein, but platelet CE% was higher in the absence of M-protein (P = 0.0,003), without any reduction in peripheral patients platelets. We, therefore, conclude that in the setting of MM patients with a high WBCs count and/or low percentage of peripheral CD34+ cells, collections with V4.7 or adjusted cycle volume V6.0 gave comparable result in CD34+ CE%. RBCs and platelets contamination is higher if low cycle volume is chosen. In hard to mobilize patients, V4.7 is advisable. J. Clin. Apheresis, 2009. © 2009 Wiley-Liss, Inc. [source] Prediction of marginal bone loss and tooth loss , a prospective study over 20 yearsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 8 2002Leif Jansson Abstract Aim: The purpose of the study was to investigate the influence of potential risk predictors/risk factors on the longitudinal marginal bone loss and tooth loss over 20 years. Material and Methods: A clinical and radiographic investigation of a sample of 513 individuals was performed in 1970 and 1990. Stepwise multiple regression analyses were adopted to calculate the influence of the potential risk predictors/risk factors on the longitudinal marginal bone loss and tooth loss. Results: Russell's Periodontal Index in 1970 and smoking were significantly and positively correlated to longitudinal bone loss. Russell's Periodontal Index, marginal bone loss and Plaque Index at baseline were positively and significantly correlated to the longitudinal tooth loss, whilst age, the number of missing teeth in 1970 and the number of school years showed a significant negative correlation to number of teeth lost between 1970 and 1990. Conclusions: Smoking was found to be a significant risk factor in marginal bone loss, while plaque was a risk factor in tooth loss. However, the regression models explained a low percentage of the total variance, especially for marginal bone loss. [source] Organizational socialization of volunteers: the effect on their intention to remain,JOURNAL OF COMMUNITY PSYCHOLOGY, Issue 5 2009M. Carmen Hidalgo Identifying the factors affecting the retention of volunteers in their activities is one of the main objectives for researchers and volunteer managers. There have been many studies with this aim and many factors affecting sustained volunteerism have been identified. However, one of the limits of these models is the low percentage of explained variance, which indicates that there are other additional factors, yet unidentified, which may have an important influence in the prediction of durability as a volunteer. In our study, we intend to analyze the effect that some factors of organizational socialization of volunteers have on their intention to remain volunteers. In particular, we will focus on the level of integration in the organization, evaluated from five variables: social networks, training, understanding, social support inside the organization, and characteristics of the job they perform. The statistical analysis shows that social networks, organizational support, positive task, and formation are highly significant predictors of the intention to remain a volunteer. These four variables explain 29% of the variability of the dependent variable, while the variables understanding and social support of the volunteers were excluded from the regression equation. © 2009 Wiley Periodicals, Inc. [source] Verrucous carcinoma of the axilla: case report and reviewJOURNAL OF CUTANEOUS PATHOLOGY, Issue 2 2004Chalid Assaf Background:, Verrucous carcinoma, a variant of squamous cell carcinoma, is distinct from squamous cell carcinoma in morphology and behavior. It preferentially occurs on the oropharyngeal mucosa, the urogenital mucosa, and the soles. In contrast to its malignant clinical picture, the tumor grows locally invasive but is histologically benign and metastasizes rarely. Methods:, We report the uncommon occurrence of a large verrucous carcinoma on apparently uninvolved skin in the right axilla in a 47-year-old male. Results:, Histologic examination reveals a cauliflower-like tumor consisting of deep invaginated epidermal proliferation with rabbit burrow-like, keratin-filled sinus formations; the basement membrane, however, remains intact. Immunohistology showed positivity for pancytokeratin (KL-1) and cytokeratin (CK) 18 and negativity for CK7, and assessment of the proliferative activity of the tumor cells revealed low percentage of Ki-67 expression. Furthermore, there were only scattered cells expressing p53 or bcl-2. Polymerase chain reaction excluded the presence of human papillomavirus. After complete excision, no signs of recurrence occurred over a follow-up period of three years. Conclusion:, Verrucous carcinoma should be distinguished from typical squamous cell carcinoma. The clinicopathological features, differential diagnosis, and therapy are discussed here together with the molecular biologic aspects of the tumor. [source] Temperature dependent larval resource allocation shaping adult body size in Drosophila melanogasterJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2003Z. Bochdanovits Abstract Geographical variation in Drosophila melanogaster body size is a long-standing problem of life-history evolution. Adaptation to a cold climate invariably produces large individuals, whereas evolution in tropical regions result in small individuals. The proximate mechanism was suggested to involve thermal evolution of resource processing by the developing larvae. In this study an attempt is made to merge proximate explanations, featuring temperature sensitivity of larval resource processing, and ultimate approaches focusing on adult and pre-adult life-history traits. To address the issue of temperature dependent resource allocation to adult size vs. larval survival, feeding was stopped at several stages during the larval development. Under these conditions of food deprivation, two temperate and two tropical populations reared at high and low temperatures produced different adult body sizes coinciding with different probabilities to reach the adult stage. In all cases a phenotypic trade-off between larval survival and adult size was observed. However, the underlying pattern of larval resource allocation differed between the geographical populations. In the temperate populations larval age but not weight predicted survival. Temperate larvae did not invest accumulated resources in survival, instead they preserved larval biomass to benefit adult weight. In other words, larvae from temperate populations failed to re-allocate accumulated resources to facilitate their survival. A low percentage of the larvae survived to adulthood but produced relatively large flies. Conversely, in tropical populations larval weight but not age determined the probability to reach adulthood. Tropical larvae did not invest in adult size, but facilitated their own survival. Most larvae succeeded in pupating but then produced small adults. The underlying physiological mechanism seemed to be an evolved difference in the accessibility of glycogen reserves as a result of thermal adaptation. At low rearing temperatures and in the temperate populations, glycogen levels tended to correlate positively with adult size but negatively with pupation probability. The data presented here offer an explanation of geographical variation in body size by showing that thermal evolution of resource allocation, specifically the ability to access glycogen storage, is the proximate mechanism responsible for the life-history trade-off between larval survival and adult size. [source] Food energy content influences food portion size estimation by nutrition studentsJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 3 2010C. C. Japur Abstract Background:, Food portion size estimation involves a complex mental process that may influence food consumption evaluation. Knowing the variables that influence this process can improve the accuracy of dietary assessment. The present study aimed to evaluate the ability of nutrition students to estimate food portions in usual meals and relate food energy content with errors in food portion size estimation. Methods:, Seventy-eight nutrition students, who had already studied food energy content, participated in this cross-sectional study on the estimation of food portions, organised into four meals. The participants estimated the quantity of each food, in grams or millilitres, with the food in view. Estimation errors were quantified, and their magnitude were evaluated. Estimated quantities (EQ) lower than 90% and higher than 110% of the weighed quantity (WQ) were considered to represent underestimation and overestimation, respectively. Correlation between food energy content and error on estimation was analysed by the Spearman correlation, and comparison between the mean EQ and WQ was accomplished by means of the Wilcoxon signed rank test (P < 0.05). Results:, A low percentage of estimates (18.5%) were considered accurate (±10% of the actual weight). The most frequently underestimated food items were cauliflower, lettuce, apple and papaya; the most often overestimated items were milk, margarine and sugar. A significant positive correlation between food energy density and estimation was found (r = 0.8166; P = 0.0002). Conclusions:, The results obtained in the present study revealed a low percentage of acceptable estimations of food portion size by nutrition students, with trends toward overestimation of high-energy food items and underestimation of low-energy items. [source] Oral candidiasis as a clinical marker related to viral load, CD4 lymphocyte count and CD4 lymphocyte percentage in HIV-infected patientsJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 1 2002J. Campo Abstract Background:, High viral load is currently considered to be one of the main indicators of the progression of HIV-induced immunodepression, but few studies have analysed its relationship to the presence of oral candidiasis (OC). The aim of this cross-sectional study is to analyse the relationship between viral load, total CD4 lymphocyte count, and percentage of CD4 lymphocytes to the occurrence of OC. Methods:, The present cross-sectional study included 156 HIV-infected patients seen at a clinic for sexually transmitted diseases and HIV. We assesed the presence or absence of OC, and microbiological samples were obtained from the palatine mucosa and dorsal tongue for a smear stained with KOH (potassium hydroxide) and culture on Sabouraud's dextrose agar in all patients. Viral load was determined by quantification of viral RNA in peripheral blood with a minimum detectable level of 500 RNA copies/ml. CD4+ counts/CD4+ percentage were categorized as <200/<14%, 200,499/14,28%, and >500/>29%, and HIV viral loads were categorized as <500, 500,10,000, >10,000 copies/ml. Results:, Thirty-eight percent (37.8%) of the patients had OC. Patients with CD4+ lymphocyte counts below 200×106/l and CD4+ percentages below 14% showed a significantly higher frequency of OC (57.9% and 48.0%, respectively). Patients with a viral load over 10,000 copies/ml also had OC more frequently (44.8%). In the multiple logistic regression analysis, OC showed a statistically significant association with high viral load [>10,000 vs <500, odds ratio (OR)=11.4], low percentage of CD4+ lymphocytes (<14% vs >28%, OR=5), and injection drug use (IDU vs heterosexual transmission, OR=10.2). In HIV-infected patients, high viral load was associated with more frequent OC, regardless of CD4+ lymphocyte level. Conclusions:, These findings suggest that oral candidiasis could be a useful clinical marker of patients with high viral load. In view of these results, emphasis should be placed on the importance of systematic examination of the oral cavity in all medical follow-up examinations of HIV-infected patients. [source] Added nitrogen interaction as affected by soil nitrogen pool size and fertilization , significance of displacement of fixed ammoniumJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 2 2004Shan Lin Abstract Displacement of NH4+ fixed in clay minerals by fertilizer 15NH4+ is seen as one mechanism of apparent added nitrogen interactions (ANI), which may cause errors in 15N tracer studies. Pot and incubation experiments were carried out for a study of displacement of fixed NH4+ by 15N-labeled fertilizer (ammonium sulfate and urea). A typical ANI was observed when 15N-labeled urea was applied to wheat grown on soils with different N reserves that resulted from their long-term fertilization history: Plants took up more soil N when receiving fertilizer. Furthermore, an increased uptake of 15N-labeled fertilizer, induced by increasing unlabeled soil nitrogen supply, was found. This ANI-like effect was in the same order of magnitude as the observed ANI. All causes of apparent or real ANI can be excluded as explanation for this effect. Plant N uptake-related processes beyond current concepts of ANI may be responsible. NH4+ fixation of fertilizer 15NH4+ in sterilized or non-sterile, moist soil was immediate and strongly dependent on the rate of fertilizer added. But for the tested range of 20 to 160 mg 15NH4+ -N kg,1, the NH4+ fixation rate was low, accounting for only up to 1.3,% of fertilizer N added. For sterilized soil, no re-mobilization of fixed 15NH4+ was observed, while in non-sterile, biologically active soil, 50,% of the initially fixed 15NH4+ was released up to day 35. Re-mobilization of 15NH4+ from the pool of fixed NH4+ started after complete nitrification of all extractable NH4+. Our results indicate that in most cases, experimental error from apparent ANI caused by displacement of fixed NH4+ in clay is unlikely. In addition to the low percentage of only 1.3,% of applied 15N, present in the pool of fixed NH4+ after 35 days, there were no indications for a real exchange (displacement) of fixed NH4+ by 15N. Einfluss der Düngung und des N-Bodenvorrats auf Added Nitrogen Interactions , Bedeutung des Ersatzaustauschs mit in Tonmineralen fixiertem Ammonium Ersatzaustausch (displacement) von in Tonmineralen fixiertem NH4+ durch Dünger- 15NH4+ gilt als eine Ursache für scheinbare (apparente) Added Nitrogen Interactions (ANI). Diese werden als Fehlerursache in 15N-Tracerstudien diskutiert. Durch Einsatz von 15N-markiertem Ammoniumsulfat und Harnstoff wurde in Inkubations- und Gefäßversuchen geprüft, welche Bedeutung der Ersatzaustausch von gedüngtem 15NH4+ mit in Tonmineralen fixiertem Ammonium hat. Mit zwei Böden, die sich nur in ihrer Düngungsgeschichte unterschieden, zeigte sich nach Düngung mit 15N-markiertem Harnstoff zu Weizen eine typische ANI: Nach Düngung nahmen die Pflanzen nicht nur Dünger-N, sondern auch mehr Boden-N auf. Zusätzlich zeigte sich, dass die Pflanzen bei gleicher Düngung mehr Dünger-N aufnahmen, wenn sie auf Boden mit größerem N-Vorrat wuchsen. Beide Effekte hatten die gleiche Größenordnung. Dieser Befund kann mit den bisher beschriebenen Ursachen für ANI nicht erklärt werden. Wahrscheinlicher scheint eine Beeinflussung der aktiven, pflanzlichen N-Aufnahme. Die Fixierung von Dünger- 15NH4+ in sterilisiertem oder nicht sterilisiertem, frischem Boden erfolgte unmittelbar und hing von der gedüngten N-Menge ab. Innerhalb des untersuchten Bereichs von 20 bis 160 mg 15NH4+ -N kg,1 wurden nur 1,3,% des gedüngten NH4+ in Tonmineralen fixiert. Dieses fixierte NH4+ wurde bei zuvor sterilisiertem Boden nicht wieder freigesetzt. Hingegen wurden aus den Tonmineralen des biologisch aktiven, nicht sterilisierten Bodens innerhalb des 35-tägigen Versuchszeitraums 50,% des fixierten NH4+ wieder freigesetzt. Diese Freisetzung setzte in dem Moment ein, als der Vorrat des leicht verfügbaren, 2 M KCl-extrahierbaren NH4+ durch Nitrifikation vollständig erschöpft war. Unsere Ergebnisse zeigen, dass Versuchsfehler durch Ersatzaustausch mit Tonmineral-fixiertem Ammonium als Ursache für die scheinbare ANI in den meisten Fällen auszuschließen sein dürften. Innerhalb von 35 Tagen traten maximal 1,3,% des gedüngten 15N-markierten Dünger-N in die Fraktion des fixierten Ammoniums über. Hinweise für einen echten Ersatzaustausch des in Tonmineralen fixierten Ammoniums durch Dünger-N konnten nicht gefunden werden. [source] Haematological and biochemical abnormalities in canine blood: frequency and associations in 1022 samplesJOURNAL OF SMALL ANIMAL PRACTICE, Issue 7 2004S. Comazzi Submission of blood samples to referral laboratories is very common in veterinary practice. Internal reference ranges should take into account published ranges adapted to the methods and apparatus used and to the population under consideration. The aim of this study was to examine the results from 1022 consecutive canine blood tests, analysing the frequency and the main associations of abnormalities, and to compare the results in different age groups. Haemograms and serum biochemistry were compared with internal ranges and between age groups: younger than one year, one to eight years and older than eight years. Young dogs exhibited lower numbers of erythrocytes and lower values for haemoglobin concentration and packed cell volume. They also showed higher numbers of lymphocytes and higher concentrations of phosphorus and 71 per cent showed raised alkaline phosphatase. Neutrophilia, hypergammaglobulinaemia and hypoalbuminaemia occurred quite frequently in all dogs, and hypoalbuminaemia and hyperphosphataemia were commonly seen in uraemic patients. The simultaneous evaluation of cytolytic and hepatobiliary enzymes allowed better detection of liver damage, since only a very low percentage of dogs had simultaneous increases in all hepatic enzymes. [source] Sintering Behavior and Properties of Iron-Rich Glass-CeramicsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2004Alexander Karamanov Iron-rich glass-ceramics were obtained by the sintering of two glass powders, labeled G1 and G2, at heating rates of 5° and 20°C/min followed by an isothermal step in the 850°,1050°C temperature interval. The sintering process was evaluated by the linear shrinkage; the closed porosity was estimated by density measurements; the structure and the morphology of the glass ceramics were observed by scanning electron microscopy. The bending strength, the Young modulus, and Vickers hardness of the glass-ceramics materials were evaluated. The results showed that the sintering process and morphology of the glass-ceramics depends on the amount of magnetite and pyroxene formed. With a low percentage of crystal phase formed (25%,30% typical of G1) the structure is characterized by closed porosity; at higher crystallization (45%,50% typical of G2) open porosity is mainly formed. The properties of the glass-ceramics were not influenced by the heating rate but improved with an increase in the degree of crystallization. [source] Occult hepatitis B viral DNA in liver carcinomas from a region with a low prevalence of chronic hepatitis B infectionJOURNAL OF VIRAL HEPATITIS, Issue 4 2004R. Kannangai Summary., Occult hepatitis B is defined by the presence of hepatitis B viral (HBV) DNA in the serum or liver in persons lacking hepatitis B surface antigen (HBsAg) in the serum. A high prevalence of occult HBV has been reported in hepatocellular carcinoma (HCC) from Asia, but little information is available on the prevalence of occult HBV in HCC from regions with a low prevalence of typical chronic hepatitis B infection. In a retrospective study, 19 cases of primary liver cancer were investigated for the presence of occult HBV DNA by amplification of the surface, core, and X gene. In addition, HBV copy numbers were quantitated by real time polymerase chain reaction, genotyped, and samples tested for covalently closed circular HBV DNA, which is a marker of active viral replication. Occult HBV was found in three of 19 cases (16%). Genotyping was successful in two cases, both of which were genotype A. HBV DNA copy numbers were low, all less than 10 copies/,g liver DNA. No closed circular HBV DNA was detected. Thus, in this study occult HBV was of genotype A and was found in a low percentage of cases of HCC and was associated with low tissue HBV DNA copy numbers and no detectable evidence for viral replication. [source] Clinical significance of Gata-1, Gata-2, EKLF, and c-MPL expression in acute myeloid leukemia,AMERICAN JOURNAL OF HEMATOLOGY, Issue 2 2009Rosa M. Ayala The aim of this study was to evaluate the biological correlation and prognostic impact of Gata-1, Gata-2, EKLF, and c-MPL transcript level in a group of 41 acute mieloid leukemia (AML) patients. Gata-1 overexpression was related to advanced age and a low percentage of bone marrow blasts and was associated with the expression of CD34 antigen and lymphoid T markers. The negative impact of Gata-1 expression on the probability of achieving complete remission has been confirmed. Gata-2 overexpression was associated with a low percentage of blasts in BM and males. Expression of c-MPL was associated with CD34+ AML and M2 FAB AML subtype. A higher expression of EKLF was found in secondary AML versus primary AML. Nevertheless, patients expressing EKLF had a longer overall survival and event free survival than those patients that did not express EKLF. Our study has identified expression of EKLF as a factor with a favorable impact on prognosis in AML. Am. J. Hematol, 2009. © 2008 Wiley-Liss, Inc. [source] Mutagenic and antimutagenic potential of the medicinal plants M. laevigata and C. xanthocarpaPHYTOTHERAPY RESEARCH, Issue 3 2003J. B. F. Fernandes Abstract Aqueous extracts of medicinal plants (Mikania laevigata and Campomanesia xanthocarpa) were screened for the presence of mutagenic activity in the Salmonella/microsome assay. The extracts of Campomanesia xanthocarpa showed frameshift (TA97a strain) signs of mutagenic activity without exogenous metabolism (S9 fraction). The infusions of Mikania laevigata, negative for mutagenic activity, showed high percentages of inhibition of mutagenesis induced by mutagens 2AF (2-amino,uorene), in the presence of exogenous metabolism (S9 fraction), for frameshift (TA98) and base pair substitution (TA100) lesions. In addition, these inhibitions were observed against mutagen SAZ (sodium azide) in assays with the TA100 strain, without exogenous metabolism (S9 fraction). A synergistic effect was also observed in frameshift mutagenic events, with direct action in the presence of 4NQO (4-oxide-1-nitroquinoline) and a tendency to a low percentage of action enhancement, in the presence of the 2AF mutagen. The variable responses observed in the extract assays show the potentials for interaction of the different active principles in genetic material. Copyright © 2003 John Wiley & Sons, Ltd. [source] Sequencing over 13 000 expressed sequence tags from six subtractive cDNA libraries of wild and modern wheats following slow drought stressPLANT CELL & ENVIRONMENT, Issue 3 2009NESLIHAN Z. ERGEN ABSTRACT A deeper understanding of the drought response and genetic improvement of the cultivated crops for better tolerance requires attention because of the complexity of the drought response syndrome and the loss of genetic diversity during domestication. We initially screened about 200 wild emmer wheat genotypes and then focused on 26 of these lines, which led to the selection of two genotypes with contrasting responses to water deficiency. Six subtractive cDNA libraries were constructed, and over 13 000 expressed sequence tags (ESTs) were sequenced using leaf and root tissues of wild emmer wheat genotypes TR39477 (tolerant) and TTD-22 (sensitive), and modern wheat variety Kiziltan drought stressed for 7 d. Clustering and assembly of ESTs resulted in 2376 unique sequences (1159 without hypothetical proteins and no hits), 75% of which were represented only once. At this level of EST sampling, each tissue shared a very low percentage of transcripts (13,26%). The data obtained indicated that the genotypes shared common elements of drought stress as well as distinctly differential expression patterns that might be illustrative of their contrasting ability to tolerate water deficiencies. The new EST data generated here provide a highly diverse and rich source for gene discovery in wheat and other grasses. [source] Encapsulating Eu3+ complex doped layers to improve Si-based solar cell efficiencyPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 8 2009Alessia Le Donne Abstract This paper reports the electrical characterization of commercially available crystalline silicon solar cells encapsulated with poly-vinylacetate doped with different Eu3+ organic complexes. The inclusion of these complexes in the encapsulating matrix allows down-shifting of the solar spectrum components below 420,nm toward the maximum quantum efficiency of the solar cells. This effect has been proven under Air Mass 1·5 conditions (simulating terrestrial applications) where an increase of the total power delivered by the encapsulated cells has been observed. Moreover, this enhancement has been obtained using very low percentage by weight of organolanthanide dopants, allowing a reduction in the Watt peak price. At higher concentrations a strong quenching of the energy transfer from the organic antenna to the lanthanide ion has been observed. Copyright © 2009 John Wiley & Sons, Ltd. [source] Differential expression of the calcium sensing receptor and combined loss of chromosomes 1q and 11q in parathyroid carcinomaTHE JOURNAL OF PATHOLOGY, Issue 1 2004Carola J Haven Abstract Malignant transformation of parathyroid tumours is rare. Nevertheless, this small subset of malignant tumours often creates diagnostic and therapeutic problems. In this work, the morphological characteristics of 26 primary parathyroid carcinomas and seven metastases have been studied. Furthermore, immunohistochemical expression profiles for the calcium sensing receptor (CASR), cyclin D1 (CCND1), and Ki-67 were determined for parathyroid carcinomas and compared with adenomas and hyperplasias using a tissue microarray. Loss of heterozygosity (LOH) of the chromosome 1q region containing the HRPT2 gene and chromosome 11q (MEN1) was determined in the carcinomas. In contrast to the adenomas and hyperplasias, 31% of carcinomas demonstrated down-regulation of CASR. A significant correlation was found between CASR expression and the Ki-67 proliferation index. Chromosome 1q and chromosome 11q LOH were found in 12 of 22 (55%) and 11 of 22 (50%) carcinomas tested, respectively. Combined 1q and 11q LOH was seen in 8 of 22 (36%) carcinomas, in contrast to the low percentage of LOH reported in both regions in adenomas. In conclusion, this study demonstrates that combined 1q and 11q LOH in parathyroid tumours is suggestive of malignant behaviour. Strong down-regulation of the CASR protein is seen in a proportion of parathyroid carcinomas with a high proliferation index. Copyright © 2004 John Wiley & Sons, Ltd. [source] Acrosome reaction: methods for detection and clinical significanceANDROLOGIA, Issue 6 2000T. Zeginiadou The present article reviews the methods for detection and the clinical significance of the acrosome reaction. The best method for the detection of the acrosome reaction is electron microscopy, but it is expensive and labour-intensive and therefore cannot be used routinely. The most widely used methods utilize optical microscopy where spermatozoa are stained for the visualization of their acrosomal status. Different dyes are used for this purpose as well as lectins and antibodies labelled with fluorescence. The acrosome reaction following ionophore challenge (ARIC) can separate spermatozoa that undergo spontaneous acrosome reaction from those that are induced, making the result of the inducible acrosome reaction more meaningful. Many different stimuli have been used for the induction of the acrosome reaction with different results. The ARIC test can provide information on the fertilizing capability of a sample. The ARIC test was also used to evaluate patients undergoing in vitro fertilization since a low percentage of induced acrosome reaction was found to be associated with lower rates of fertilization. The cut-off value that could be used to identify infertile patients is under debate. Therapeutic decisions can also be made on the basis of the value of the ARIC test. [source] Multigene analysis for differentiation of aster yellows phytoplasmas infecting carrots in SerbiaANNALS OF APPLIED BIOLOGY, Issue 2 2009B. Duduk Abstract During a survey of large carrot fields in Serbia, plants showing leaf reddening and/or yellowing, adventitious shoot production and reduction in taproot size and quality were observed in a low percentage of plants. To verify phytoplasma association with the described symptoms and to carry out pathogen differentiation, PCR assays followed by restriction fragment length polymorphism (RFLP) analyses and/or sequencing of phytoplasma 16Sr DNA and ribosomal protein genes l22 and s3, tuf, putative aa kinase plus ribosomal recycling factor genes and DNA helicase gene were carried out. Phytoplasmas belonging to 16SrI-A and 16SrI-B ribosomal subgroups and to rpI-A and rpI-B ribosomal protein subgroups, respectively, were identified by RFLP analyses in 13 of 15 symptomatic plants tested. No amplification was obtained with non-symptomatic carrot samples. The identification was confirmed by sequence analyses of the phytoplasma genes studied. In two carrot samples, presence of interoperon sequence heterogeneity was detected and phytoplasma strains were identified as belonging to 16SrI group but were not assigned to any 16S rRNA or ribosomal protein subgroup. This research allowed the first molecular identification of phytoplasmas infecting carrot in Serbia using several molecular markers, and it indicates that under field conditions in non-epidemic outbreaks a certain amount of genetic mutation may occur in conserved genes of these prokaryotes. [source] Potential of local agricultural by-products for the rearing of African catfish Clarias gariepinus in Rwanda: effects on growth, feed utilization and body compositionAQUACULTURE RESEARCH, Issue 2 2007Laetitia Nyina-wamwiza Abstract This study was performed to evaluate the effect of replacing fish meal with local by-products on Clarias gariepinus growth performance, feed utilization and body composition. A control diet contained 50% of fish meal. In four other diets, fish meal was partially replaced by vegetable and animal protein blend composed of sunflower oil cake, soybean oil cake, groundnut oil cake, bean meal, chicken viscera and blood meal. The study was conducted in a recirculating water system at a mean temperature of 23.6°C. The five test diets were compared with a commercial diet developed for African catfish. All diets were balanced to be equal in gross energy (19 kJ g,1) and crude protein (40%). The experimental groups were fed in triplicate for 8 weeks, increasing fish weight from about 6.2 g at start to 52.3 g in the end. Best specific growth rate (SGR=3.4), feed efficiency (FE=1.3) and protein efficiency ratio (PER=3) were obtained with the control diet (diet 50% fish meal), although there were no significant differences between the group of fish fed the control diet and those fed diets based on groundnut oil cake or bean meal, whereas SGR (2.17), FE (0.85) and PER (1.95) were significantly (P<0.01) lower in fish fed diet containing sunflower oil cake. No significant differences (P<0.05) were found in fish fed commercial diet and diets containing bean meal or groundnut oil cake. Groundnut oil cake or bean meal can thus replace at least 50% of fish meal in the diet of Clarias fingerlings without amino acid supplementation. Because of its economic importance and its potential in animal nutrition sunflower oil cake is still an interesting feed ingredient, but its efficiency should be improved by various processing techniques. African catfish can utilize efficiently a diet with low percentage of animal protein without growth reduction. [source] Low glycosylated ferritin, a good marker for the diagnosis of hemophagocytic syndromeARTHRITIS & RHEUMATISM, Issue 5 2008Laurence Fardet Objective A very low percentage of glycosylated ferritin (<20%) has only been reported in association with adult-onset Still's disease (AOSD), a disease classically associated with hemophagocytic syndrome. We undertook this study to determine whether hemophagocytic syndrome outside the context of AOSD is also associated with a very low percentage of glycosylated ferritin. Methods From October 2006 to September 2007, the serum level of glycosylated ferritin was determined in all consecutive patients seen in 3 departments and for whom the diagnosis of hemophagocytic syndrome was suspected. The level of glycosylated ferritin in these patients was compared with that in age- and sex-matched controls with a marked inflammatory syndrome not associated with hemophagocytic syndrome. We assessed the value of glycosylated ferritin as a marker for the diagnosis of hemophagocytic syndrome. Results Forty-two patients were included in the study (14 with confirmed hemophagocytic syndrome, 7 with suspected but unconfirmed hemophagocytic syndrome, and 21 controls). The median level (interquartile range [IQR]) of total serum ferritin was significantly higher in patients with confirmed hemophagocytic syndrome (3,344 ,g/liter [2,074,7,334]) than in patients with suspected but unconfirmed hemophagocytic syndrome (555 ,g/liter [464,1,420]) (P = 0.02) or in controls (451 ,g/liter [126,929]) (P < 0.001). The median (IQR) percentage of glycosylated ferritin was significantly lower in patients with confirmed hemophagocytic syndrome (10% [3,14]) than in patients with suspected but unconfirmed hemophagocytic syndrome (40% [36,47]) (P < 0.001) or in controls (36% [26,49]) (P < 0.001). The diagnostic performance of glycosylated ferritin tended to be higher than that of total serum ferritin for the diagnosis of hemophagocytic syndrome (area under the receiver operating characteristic curve [95% confidence interval] 0.97 [0.92,1.00] versus 0.79 [0.59,1.00]; P = 0.10). Conclusion These results suggest that glycosylated ferritin may be a helpful marker for the diagnosis of hemophagocytic syndrome. [source] Immune Function Tests for Hazard Identification: A Paradigm Shift in Drug DevelopmentBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 4 2006Elizabeth R. Gore The purpose of the more stringent approach to immunotoxicology testing was to better identify unintended immunosuppression; however, the requirement was met with much discussion and debate. At the center of the discussion was an attempt to reconcile opposing regulatory directives from agencies outside of Europe that adhere to a more selective, weight-of-evidence approach to functional evaluations. Uncertainty over the predictive value of the recommended immune function tests relative to conventional toxicology parameters prompted an investigation by the International Committee on Harmonization (ICH). The results of a preliminary, industry-wide survey indicated that only a low percentage of pharmaceuticals adversely affect immune function without alterations to standard toxicology parameters. Expected ICH guidelines will ultimately determine to what extent and for what purpose immune function tests will be conducted. In the meantime, optimization of the recommended immune function tests is ongoing. The T-cell dependent antibody response (TDAR) by either conventional Sheep Red Blood Cell (SRBC) plaque assay or by the modified ELISA method using either SRBC or keyhole limpet hemocyanin (KLH) as antigen is being extensively evaluated to determine best practices and procedures for preclinical immunotoxicity evaluations. This review addresses some aspects of the debate concerning the appropriateness of immune function tests for hazard identification, along with recommendations for optimizing TDAR methodology to ensure adequate sensitivity and predictability in risk assessments for immunotoxicity. [source] Sexual devolution in plants: apomixis uncloaked?BIOESSAYS, Issue 9 2008Richard D. Noyes There are a growing number of examples where naturally occurring mutations disrupt an established physiological or developmental pathway to yield a new condition that is evolutionary favored. Asexual reproduction by seed in plants, or apomixis, occurs in a diversity of taxa and has evolved from sexual ancestors. One form of apomixis, diplospory, is a multi-step development process that is initiated when meiosis is altered to produce an unreduced rather than a reduced egg cell. Subsequent parthenogenetic development of the unreduced egg yields genetically maternal progeny. While it has long been apparent from cytological data that meiosis in apomicts was malfunctional or completely bypassed, the genetic basis of the phenomenon has been a long-standing mystery. New data from genetic analysis of Arabidopsis mutants1 in combination with more sophisticated molecular understanding of meiosis in plants indicate that a weak mutation of the gene SWI, called DYAD, interferes with sister chromatid cohesion in meiosis I, causes synapsis to fail in female meiosis and yields two unreduced cells. The new work shows that a low percentage of DYAD ovules produce functional unreduced egg cells (2n) that can be fertilized by haploid pollen (1n) to give rise to triploid (3n) progeny. While the DYAD mutants differ in some aspects from naturally occurring apomicts, the work establishes that mutation to a single gene can effectively initiate apomictic development and, furthermore, focuses efforts to isolate apomixis genes on a narrowed set of developmental events. Profitable manipulation of meiosis and recombination in agronomically important crops may be on the horizon. BioEssays 30:798,801, 2008. © 2008 Wiley Periodicals, Inc. [source] An update on the first decade of the European centralized procedure: how many innovative drugs?BRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 5 2006Domenico Motola What is already known about this subject ,,We recently proposed an algorithm to assess the degree of therapeutic innovation of new therapeutic agents. It was based on the disease seriousness, the availability of previous treatments and the extent of the therapeutic effect, and was applied to all therapeutic agents approved by the EMEA in the period 1995,2003. ,,A low percentage (32%) of important therapeutic innovation was found. This figure may be an underestimate of the actual level of innovation, because common biotechnological products, such as recombinant human insulins, must follow the centralized procedure. What this study adds ,,Details for each agent, focusing on the comparison of the degree of therapeutic innovation between biotechnological and nonbiotechnological therapeutic agents approved by EMEA during the its first decade of activity (1995,2004). The underlying hypothesis was that the latter have a higher degree of innovation because they followed the centralized procedure on the assumption that they are innovative. ,,The percentage of important therapeutic innovation was low not only for biotechnological products (25%), as expected because they include many already known products such as insulins, but also for nonbiotechnological therapeutic agents (29%). Aims In a previous paper, we proposed an algorithm to assess the degree of therapeutic innovation of the agents approved by the European centralized procedure, which must be followed by biotechnological products and is optional for drugs claimed as innovative. A low overall degree of therapeutic innovation (about 30%) was found. This figure may be an underestimate of the actual level of innovation, because common biotechnological products, such as recombinant human insulins, must follow this procedure. To test the hypothesis that therapeutic innovation prevails among nonbiotechnological products, we evaluated separately the degree of therapeutic innovation of biotechnological vs. nonbiotechnological agents in the first decade of European Medicines Agency activity, also studying a possible time trend. Methods We assessed, for each drug: (i) the seriousness of the target disease, (ii) the availability of previous treatments, and (iii) the extent of therapeutic effect according to the previously proposed algorithm. Results Our analysis considered 251 medicinal products corresponding to 198 active substances, classified according to four main areas as therapeutic agents (88.9%), diagnostics (5.5%), vaccines (5.1%) and life-style drugs (0.5%). Among all therapeutic agents, 49 out of 176 agents (28%) were classified as having an important degree of therapeutic innovation. Fifteen out of 60 biotechnological therapeutic agents were considered important therapeutic innovations (25%), whereas this figure was 29% for nonbiotechnological agents. Conclusions Among active substances claimed as innovative by the manufacturers, only a minority deserve this definition according to our algorithm. [source] Are mesenchymal stromal cells from children resistant to apoptosis?CELL PROLIFERATION, Issue 3 2009H. Dimitriou Objectives:, Mesenchymal stromal cells (MSC) represent a novel cellular candidate in the field of transplantation and tissue regeneration. Their clinical application requires their in vitro expansion. The aim of this study was to assess the effect of conditions that would favour apoptosis, and of long-term expansion, on the characteristics of MSC from children. Materials and methods:, Bone marrow mononuclear cells were cultured for 10 passages (P1,P10). Expression of CD105, CD146, CD95 and apoptosis by 7-amino-actinomycin D staining were evaluated. CFU-F and cell doubling time (DT) were assessed in every passage. Cell-cycle study was performed at P2 and P6. Results:, CFU-F decreased from 38 ± 3.7 at P2 to 9.6 ± 3.2 per 10 MSC/cm2 at P10 and DT increased from 1.93 ± 0.1 (P2) to 6.1 ± 2.45 days (P10). A low percentage of apoptotic (dead) cells was detected at P2 and this did not change until P10. Cells at P2 were at G0/G1 phase, but in advanced passages more cells were in an active state. Induction of apoptosis (addition of anti-Fas agonist antibody) using standard culture conditions, showed a minor effect on MSC survival. Serum deprivation of MSC (up to 72 h) revealed no substantial apoptotic effect while cells retained their tri-lineage differentiation capacity. Conclusions:, We conclude that MSC from children retain their functional characteristics throughout serial passages and remain stable under conditions that usually cause apoptosis. These features render MSC, especially those of early passages, optimal candidates for use in clinical applications. [source] Disease patterns of outpatient visits by Japanese expatriate children in ThailandACTA PAEDIATRICA, Issue 3 2009Rie Sakai Abstract Aim: To clarify the health-related conditions of Japanese expatriate children in Thailand. Methods: Records of Japanese children who consulted outpatient clinics at Bangkok Hospital in 2005 and 2006 (n = 2141) were analysed, and then compared with data from the patient survey conducted by the Ministry of Health, Labour and Welfare of Japan in 2005 (n = 575 400). Results: ,diseases of the respiratory system', categorized as chapter X under ICD-10 was the most frequent category in both Thailand and Japan. Although ,certain infectious and parasitic diseases' (chapter I) was the second most frequent category in Thailand, it was infrequent in Japan. In the subcategories of ,diseases of the respiratory system', ,acute upper respiratory infections' was frequent and asthma was infrequent in Thailand. Conversely, ,acute upper respiratory infections' showed a low percentage and asthma was the most frequently observed disease in Japan. Conclusion: This study examined Japanese children having the same genetic background but divided into two groups according to different living environments. Results demonstrate that children living in Japan contract asthma more frequently than infectious diseases, whereas those living in Thailand show the opposite trend, which supports the hygiene hypothesis that infections may protect against the development of allergic diseases, such as asthma. [source] |