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Selected AbstractsLaminin and fibronectin modulate inner ear spiral ganglion neurite outgrowth in an in vitro alternate choice assayDEVELOPMENTAL NEUROBIOLOGY, Issue 13 2007Amaretta R. Evans Abstract Extracellular matrix (ECM) molecules have been shown to function as cues for neurite guidance in various populations of neurons. Here we show that laminin (LN) and fibronectin (FN) presented in stripe micro-patterns can provide guidance cues to neonatal (P5) inner ear spiral ganglion (SG) neurites. The response to both ECM molecules was dose-dependent. In a LN versus poly- L -lysine (PLL) assay, neurites were more often observed on PLL at low coating concentrations (5 and 10 ,g/mL), while they were more often on LN at a high concentration (80 ,g/mL). In a FN versus PLL assay, neurites were more often on PLL than on FN stripes at high coating concentrations (40 and 80 ,g/mL). In a direct competition between LN and FN, neurites were observed on LN significantly more often than on FN at both 10 and 40 ,g/mL. The data suggest a preference by SG neurites for LN at high concentrations, as well as avoidance of both LN at low and FN at high concentrations. The results also support a potential model for neurite guidance in the developing inner ear in vivo. LN, in the SG and osseus spiral lamina may promote SG dendrite growth toward the organ of Corti. Within the organ of Corti, lower concentrations of LN may slow neurite growth, with FN beneath each row of hair cells providing a stop or avoidance signal. This could allow growth cone filopodia increased time to sample their cellular targets, or direct the fibers upward toward the hair cells. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007 [source] Leptin and endothelin-1 mediated increased extracellular matrix protein production and cardiomyocyte hypertrophy in diabetic heart diseaseDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 5 2009Pijush Majumdar Abstract Background We investigated the role of leptin and its interaction with endothelin 1 (ET-1) in fibronectin (FN) synthesis and cardiomyocyte hypertrophy, two characteristic features of diabetic cardiomyopathy. Methods Endothelial cells [human umbilical vein endothelial cells (HUVECs)] were examined for FN production and neonatal rat cardiomyocytes for hypertrophy, following incubation with glucose, ET-1, leptin and specific blockers. FN, ET-1, leptin and leptin receptors mRNA expression and FN protein were measured. Myocytes were also morphometrically examined. Furthermore, hearts from streptozotocin-diabetic rats were analysed. Results Glucose caused increased FN mRNA and protein expression in HUVECs and cardiomyocytes hypertrophy along with upregulation of ET-1 mRNA, leptin mRNA and protein. Glucosemimetic effects were seen with leptin and ET-1. Leptin receptor antagonist (leptin quadruple mutant) and dual endothelin A endothelin B (ETA/ETB) receptor blocker bosentan normalized such abnormalities. Hearts from the diabetic animals showed hypertrophy and similar mRNA changes. Conclusion These data indicate that in diabetes increased FN production and cardiomyocyte hypertrophy may be mediated through leptin with its interaction with ET-1. Copyright © 2009 John Wiley & Sons, Ltd. [source] Rapid review of liquid-based smears as a quality control measureDIAGNOSTIC CYTOPATHOLOGY, Issue 3 2004Sheryl Henderson M.Med.Sc.(Cytol.) Abstract The objective of this study was to investigate the effectiveness of a standardized method of rapid review (RR) of monolayer preparations for the identification of abnormalities, the presence of an endocervical component and infectious agents. A total of 200 ThinPrep (Cytyc, Boxborough, MA) slides representing the spectrum of abnormalities commonly encountered in cervical/vaginal cytologic specimens was retrieved from archive. The study set comprised 129 cases within normal limits (WNL); 36 low-grade epithelial abnormalities (LGEA); 28 high-grade epithelial abnormalities (HGEA), including 2 endocervical adenocarcinomas in situ (AIS) and 7 carcinomas. Eighteen false negative (FN) cases were also included for study. Originally missed on initial review, these cases were found to be abnormal on quality control review (17 LGEA; 1 AIS). Commonly encountered infectious agents were represented and included Candida albicans, Trichomonas vaginalis, herpes simplex virus, and Actinomyces. The slides were reviewed using a standardized method of RR (turret technique, for 60 sec) by three experienced screeners masked to the original reference diagnosis. Median sensitivity for LGEA was 70% (range, 67,72%); HGEA, 69% (range, 54,80%); and FN, 65% (range, 56,78%). Specificity remained high, median specificity for LGEA was 95%; HGEA, 97%; and FN, 100%. There was no significant overcalling of any diagnostic category. The chi-square test at P < 0.05 showed no significant difference between RR and full manual rescreen of the ThinPrep smears in this study. While no statistical difference was proven, the sensitivity measurements for all categories of abnormality were moderate due to the high proportion of atypical cases included into the study set. Abnormalities on the monolayer preparations frequently displayed fewer, smaller groups of disaggregated cells with rounded cytoplasmic outlines that were difficult to discern on RR. Interobserver variation was noted. Monolayers with a paucity of diagnostic cells and those displaying subtle nuclear atypia were often overlooked. Diagn. Cytopathol. 2004;31:141,146. © 2004 Wiley-Liss, Inc. [source] Radiologically guided percutaneous fine-needle aspiration biopsy of the liver: Retrospective study of 119 cases evaluating diagnostic effectiveness and clinical complicationsDIAGNOSTIC CYTOPATHOLOGY, Issue 5 2002Ph.D., Ziwen Guo M.D. Abstract We reviewed 119 percutaneous, radiologically guided fine-needle aspirations (FNA) from 114 patients with liver masses to evaluate diagnostic effectiveness and complications of this procedure. Satisfactory material was obtained in 118 cases (99%), of which 78 were diagnosed as positive (66%), three suspicious (2%), five atypical (4%), and 32 (27%) as negative for malignancy. Compared to surgical biopsy (48 cases) and clinical data, the sensitivity and specificity of FNA for malignancy was 95.1% and 100%, respectively, yielding a positive predictive value of 100% and a negative predictive value of 88.8%. Four cytology cases (3.4%) were false-negatives (FN); all were interpretive errors. Four FN surgical biopsies (8.3%) were sampling errors. Minor complications occurred in three cases (2.5%). We conclude that FNA is safe and effective for determining the malignant potential of liver masses and should be the procedure of choice. Our experience suggests that having a pathologist present in the radiology suite provides optimal patient care. Diagn. Cytopathol. 2002;26:283,289. © 2002 Wiley-Liss, Inc. [source] Follicular variant of papillary carcinoma: Cytologic findings on FNAB samples,experience with 16 casesDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2001Franco Fulciniti M.D. Abstract Between January 1, 1992 and December 31, 1997, a cytopathological diagnosis of follicular variant of papillary thyroid carcinoma (FVPC) was made on a series of 16 out of 18 patients with palpable nodules who underwent fine-needle aspiration biopsy (FNAB) in our Department. The results of aspiration biopsy were followed by histopathological examination of the surgically excised tissues. There were three false-negative aspirations (16.6%), of which two were probably bound to fine-needle sampling and one due to a mixture of benign and malignant cells which had originally gone unrecognized. The accuracy of the cytopathologic diagnosis in this variant was 88.8%. An analysis of the diagnostic cytopathological criteria was performed, which demonstrated the importance of both architectural features (monolayered and branching sheets, microacinar structures, and their combinations) and nuclear features (presence of nuclear grooves). Background -bound features were mainly represented by dense, nonfilamentous colloid. The cytopathologic findings in FVPC were compared to those found in a series of 10 usual papillary carcinomas (UPC) and 10 follicular neoplasms (FN). These latter had originally been diagnosed by FNAB and were subsequently classified histologically as follicular adenoma (n = 6), follicular carcinoma (n = 3), or adenomatoid colloid nodule (n = 1). Statistical evaluation was performed on the cytopathological findings in the three classes of lesions (FVPC, UPC, and FN) as to their presence and relative frequency or absence by using a nonparametric one-way ANOVA (Kruskall-Wallis) and, where necessary, a Mann-Whitney U test. Papillary cellular fragments and multinucleated giant cells (P < 0.005), nonfilamentous dense colloid, squamoid cells, and syncytia were significantly more represented in UPC than in FVPC (P < 0.05), while histiocytes were significantly more frequent in FVPC (P < 0.005). Other nuclear and/or background features were significant only in the distinction between papillary carcinomas as a group and FN. The cytological differential diagnosis of the FVPC is briefly discussed with relevance to the possible pitfalls caused by its peculiar cyto- and histomorphology. Diagn. Cytopathol. 2001;25:86,93. © 2001 Wiley-Liss, Inc. [source] Once-per-cycle pegfilgrastim in breast cancer patients treated with docetaxel/epidoxorubicin/cyclophosphamideEUROPEAN JOURNAL OF CANCER CARE, Issue 2 2010L. MONTELLA md MONTELLA L., ADDEO R., GUARRASI R., CENNAMO G., FAIOLA V., CAPASSO E., CARAGLIA M. & DEL PRETE S. (2010) European Journal of Cancer Care19, 200,204 Once-per-cycle pegfilgrastim in breast cancer patients treated with docetaxel/epidoxorubicin/cyclophosphamide The incidence of neutropenia following combination chemotherapy is significant in breast cancer and impairs patients' quality of life. Colony-stimulating factors significantly decrease the risk of febrile neutropenia (FN). Aim of the present study was to assess the efficacy and safety profile of once-per-cycle pegfilgrastim in reducing FN in breast cancer patients treated with docetaxel (75 mg/m2), epidoxorubicin (75 mg/m2), cyclophosphamide (500 mg/m2) administered every 3 weeks. Thirty-five breast cancer patients were enrolled. Chemotherapy was administered in adjuvant, neoadjuvant and metastatic setting respectively in 26, 4 and 5 patients. Toxicity was monitored with programmed clinical evaluation and blood sampling. All patients completed the therapeutic programme consisting of six cycles for overall 210 cycles. The FN appeared in 6 out of 35 patients (17%), requiring dose reduction in 3 patients. Hypertransaminasemia was registered in two patients. In one patient pegfilgrastim administration was stopped because of skin hypersensititivity reaction. In conclusion, pegfilgrastim was able to maintain doses and timing of docetaxel/epidoxorubicin/cyclophosphamide in almost all breast cancer patients treated in this series. The reduced need for daily administration of colony-stimulating factors, blood sampling, antibiotic therapy and hospitalization has a significant impact in terms of both quality of life and pharmaco-economic evaluations. [source] Role for cAMP-protein kinase A signalling in augmented neutrophil adhesion and chemotaxis in sickle cell diseaseEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2007Andreia A. Canalli Abstract The significance of the leukocyte in sickle cell disease (SCD) pathophysiology is becoming increasingly recognised; we sought to examine whether the chemotactic properties of neutrophils of SCD individuals may be altered and, further, to better understand the signalling events that mediate altered SCD neutrophil function. Adhesion to immobilised fibronectin (FN) and chemotaxis of control and SCD neutrophils were assessed using in vitro static adhesion assays and 96-well chemotaxis chamber assays. Adhesion assays confirmed a significantly higher basal adhesion of SCD neutrophils to FN, compared with control neutrophils. Chemotaxis assays established, for the first time, that SCD neutrophils demonstrate greater spontaneous migration and, also, augmented migration in response to IL-8, when compared with control neutrophils. Co-incubation of SCD neutrophils with KT5720 (an inhibitor of PKA) abrogated increased basal SCD neutrophil adhesion, spontaneous chemotaxis and IL-8-stimulated chemotaxis. Stimulation of SCD neutrophils with IL-8 also significantly augmented SCD neutrophil adhesion to FN with a concomitant increase in cAMP levels and this increase in adhesion was abolished by KT5720. Interestingly, the adhesive properties of neutrophils from SCD individuals on hydroxyurea therapy were not significantly altered and results indicate that a reduction in intracellular cAMP may contribute to lower the adhesive properties of these cells. Data indicate that up-regulated cAMP signalling plays a significant role in the altered adhesive and migratory properties in SCD neutrophils. Such alterations may have important implications for the pathophysiology of the disease and the cAMP-PKA pathway may represent a therapeutic target for the abrogation of altered leukocyte function. [source] Effect of Silicate-Substitution on Attachment and Early Development of Human Osteoblast-Like Cells Seeded on Microporous Hydroxyapatite Discs,ADVANCED ENGINEERING MATERIALS, Issue 1-2 2010Katharina Guth Hydroxyapatite (HA) is a well-established graft material used in bone repair. Silicon-substituted hydroxyapatite (SA; 0.8,wt% Si) has shown greater bone ingrowth and bone coverage than phase pure HA. To assess the effect of microporosity on sensitivity of cell attachment to surface physiochemistry, microporous SA and HA discs, and control Thermanox (TMX) discs were incubated with osteoblast-like cells (5,×,104 HOS-TE85 cells) under differing tissue culture conditions. To investigate early cellular attachment, organization, and differentiation, cells were also stained for integrin,,5,1, actin, and runt-related transcription factor (RUNX-2), respectively, after incubation on HA, SA, and TMX discs for 3 days. No significant differences emerged between HA, SA, and TMX discs in mean numbers of cells attached in serum free medium (SFM) over 90,min incubation. In contrast, significantly more cells were attached to SA than HA after 180,min incubation in complete medium (C-MEM) containing fetal calf serum (p,<,0.05). Cell attachment to SA and HA discs pre-conditioned in SFM supplemented with fibronectin (FN) was lower than discs pre-conditioned in C-MEM, suggesting sensitivity of an active FN conformation to the presence of co-adsorbates. Confocal microscopy demonstrated significantly more co-localization of integrin ,5,1 and actin on SA than HA. Translocalization of RUNX-2 to the nucleus was stronger in cells incubated on SA. Microporosity did not diminish the effect of surface physiochemistry on cell adhesion, and enhanced cell attachment for SA appears to be mediated by differences in the quality of adsorbed protein rather than via direct effects of substrate chemistry. [source] Subnational political opportunity structures and the success of the radical right: Evidence from the March 2004 regional elections in FranceEUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 6 2007ELINA KESTILÄ The concept of ,political opportunity structure' refers to the degree of openness of a particular political system and the external institutional or socio-economic constraints and opportunities that it sets for political parties. Comparative analysis across subnational units is conducted where the 94 departments of mainland France are the units of analysis. The significance of electoral institutions (district magnitude), party competition (effective number of parties), electoral behaviour (turnout) and socioeconomic conditions (immigration and unemployment) on the ability of the FN to gather votes across the departments is assessed by means of multiple regression. The empirical results show that the subnational political opportunity structures have been of great importance for the FN. Some four out of the five independent variables are statistically significant and explain a great deal of the variance in the two dependent variables (electoral support for FN list and index of electoral success). Turnout and district magnitude are negatively correlated with the electoral fortunes of the FN, while unemployment and the effective number of party lists are positively correlated with the success of the FN in the regional elections. The variable that indicates the share of non-European immigrants does not provide additional explanatory power in a statistically significant way. [source] Effect of Contact Mode on the Electrical Transport and Field-Emission Performance of Individual Boron NanowiresADVANCED FUNCTIONAL MATERIALS, Issue 12 2010Fei Liu Abstract Vapor,liquid,solid processing of boron nanowires (BNWs) can be carried out either using a bottom-up or top-down growth mode, which results in different contact modes between the nanowire and the substrate. The contact mode may strongly affect the electrical transport and field-emission performance of the individual boron nanowires grown on a Si substrate. The electrical transport and field-emission characteristics of individual boron nanowires of different contact modes are investigated in situ using a scanning electron microscope. The contact barriers are very distinct for the different contact modes. Moreover, the transition from a "contact-limited" to a "bulk-limited" field-emission (FE) process is demonstrated in nanoemitters for the first time, and the proposed improved metal,insulator,vacuum (MIV) model may better illustrate the nonlinear behavior of the Fowler-Nordheim (FN) plots in these nanoscale systems. Individual BNWs with different contact modes have a discrepancy in their emission stability and vacuum breakdown characteristics though they have similar aspect ratios, which suggests that their electrical transport and field-emission performance are closely related to their contact mode. Boron nanowires grown in the base-up mode have better field-emission performances and are more beneficial than those grown in the top-down mode for various device applications. [source] A novel function of WAVE in lamellipodia: WAVE1 is required for stabilization of lamellipodial protrusions during cell spreadingGENES TO CELLS, Issue 5 2005Daisuke Yamazaki When a cell spreads and moves, reorganization of the actin cytoskeleton pushes the cell membrane, and the resulting membrane protrusions create new points of contact with the substrate and generate the locomotive force. Membrane extension and adhesion to a substrate must be tightly coordinated for effective cell movement, but little is known about the mechanisms underlying these processes. WAVEs are critical regulators of Rac-induced actin reorganization. WAVE2 is essential for formation of lamellipodial structures at the cell periphery stimulated by growth factors, but it is thought that WAVE1 is dispensable for such processes in mouse embryonic fibroblasts (MEFs). Here we show a novel function of WAVE in lamellipodial protrusions during cell spreading. During spreading on fibronectin (FN), MEFs with knockouts (KOs) of WAVE1 and WAVE2 showed different membrane dynamics, suggesting that these molecules have distinct roles in lamellipodium formation. Formation of lamellipodial structures on FN was inhibited in WAVE2 KO MEFs. In contrast, WAVE1 is not essential for extension of lamellipodial protrusions but is required for stabilization of such structures. WAVE1-deficiency decreased the density of actin filaments and increased the speed of membrane extension, causing deformation of focal complex at the tip of spreading edges. Thus, at the tip of the lamellipodial protrusion, WAVE2 generates the membrane protrusive structures containing actin filaments, and modification by WAVE1 stabilizes these structures through cell-substrate adhesion. Coordination of WAVE1 and WAVE2 activities appears to be necessary for formation of proper actin structures in stable lamellipodia. [source] Impact of aboriginal ethnicity on HCV core-induced IL-10 synthesis: Interaction with IL-10 gene polymorphismsHEPATOLOGY, Issue 3 2007Koko Bate Aborsangaya The host immune response is a critical determinant in viral infection outcome. Epidemiological studies indicate that North American indigenous peoples are more resistant to chronic HCV infection than other populations. Due to the prominence of IL-10 in chronic HCV infection, we investigated the genetic tendency to produce IL-10 in Caucasian (CA) and First Nation (FN) populations. Peripheral blood mononuclear cells (PBMCs) from CA subjects had a greater tendency to produce IL-10 defined by allelic polymorphisms, as well as genotypes and haplotypes, at the -1082, -819, and -592 positions of the IL-10 promoter. More importantly, we directly evaluated the influence of ethnicity on the ability of HCV core protein to induce IL-10 synthesis and found significantly higher IL-10 production by PBMCs isolated from healthy CA subjects compared with FN subjects. Further examination of the underlying relationship between core-induced IL-10 with the high, intermediate, and low phenotypes at the -1082, -819, and -592 position revealed that spontaneous and core-induced IL-10 synthesis tended to interact negatively with defined polymorphisms. This was particularly evident for the FN cohort, in which the relationship was strengthened by a stronger interaction of core with the low,IL-10,producing phenotypes. As with previous studies, concanavalin A induced IL-10 synthesis from the CA cohort positively associated with defined genetic phenotypes. Conclusion: Cells from FN subjects had a reduced capacity to produce IL-10 in response to HCV core protein, suggesting that reduced susceptibility of FN immunity to virally induced IL-10 synthesis might contribute to epidemiological observations of enhanced HCV clearance. (HEPATOLOGY 2007;45:623,630.) [source] Compact spheroid formation by ovarian cancer cells is associated with contractile behavior and an invasive phenotypeINTERNATIONAL JOURNAL OF CANCER, Issue 9 2009Katharine L. Sodek Abstract Ovarian cancer cells are present in malignant ascites both as individual cells and as multicellular spheroid aggregates. Although spheroid formation affords protection of cancer cells against some chemotherapeutic agents, it has not been established whether a relationship exists between invasive behavior and predisposition to spheroid formation. Aspects of spheroid formation, including cell-matrix adhesion, remodeling and contractility are characteristic myofibroblast-like behaviors associated with fibrosis that contribute to tumor growth and dissemination. We explored the possibility that cell behaviors that promote spheroid formation also facilitate invasion. Our analysis of 6 human ovarian cancer cell lines indicated that ovarian cancer cells possessing myofibroblast-like properties formed compact spheroids and invaded 3D matrices. These cells readily contracted collagen I gels, possessed a spindle-like morphology, and had elevated expression of genes associated with the TGF,-mediated fibrotic response and/or ,1 integrin function, including fibronectin (FN), connective tissue growth factor (CTGF/CCN2), lysyl oxidase (LOX1), tissue transglutaminase 2 (TGM2) and urinary plasminogen activator receptor (uPAR). Whereas cell aggregation was induced by TGF,, and by ,1-integrin overexpression and activation, these treatments did not stimulate the contractile activity required for spheroid compaction. The positive relationship found between compact spheroid formation and invasive behavior implies a preferential survival of an invasive subpopulation of ovarian cancer cells, as cells in spheroids are more resistant to several chemotherapeutics. Preventing the formation of ovarian cancer spheroids may represent a novel strategy to improve the efficacy of existing therapeutics. © 2008 Wiley-Liss, Inc. [source] Effects of irrigation with treated municipal wastewater on soil properties in arid and semi-arid regions,IRRIGATION AND DRAINAGE, Issue 5 2009Sayyed Hassan Tabatabaei eaux usées; méthode d'irrigation; transports de soluté; zone aride Abstract The use of municipal wastewater for irrigation needs special management. This is due to the environmental and health hazards. In this study, secondary treated municipal wastewater was used in five irrigation treatments. These treatments were as follows: furrow irrigation with normal water (FN), drip irrigation with wastewater (DI), subsurface drip irrigation in 15,cm depth with wastewater (SDI15), subsurface drip irrigation in 30,cm depth with wastewater (SDI30), and furrow irrigation with wastewater (FW). The results showed that the application of DI and SDI sand filters causes a decrease in wastewater index pollution, including 50.1% BOD5, 98.9% total count, 97.6% total coliform, 93.2% faecal coliform, 57.1% nematode, 81% total nitrogen, 52% N-NO3, 84% N-NH4 and 44% total suspended solids. In addition, the application of the SDI system causes a decrease in the moisture content of the soil surface, which decreases total coliform and faecal coliform on the soil surface. The average values for these parameters show no significant difference (5% level) between SDI treatments and FN. The results of this research also show that in the case of SDI with its minimal leaching, prevalence contamination (such as N-NO3) was minimized as a result of the usage of wastewater at depth and in groundwater. Moreover, in SDI treatments, the maximum EC and SAR leaching are observed at 60,cm depth, whereas in the FW this leaching is observed deeper than 90,cm. Copyright © 2008 John Wiley & Sons, Ltd. L'utilisation des eaux usées municipales pour l'irrigation nécessite une gestion spéciale afin d'éviter les risques pour la santé et l'environnement. Dans cette étude des eaux usées municipales de l'usine d'Ispahan avec traitement secondaire ont été utilisées dans cinq traitements d'irrigation. Ces traitements étaient les suivants: irrigation à la raie avec de l'eau normale (FN), l'irrigation au goutte-à-goutte avec des eaux usées (DI), irrigation en sub-surface à 15,cm de profondeur avec des eaux usées (SDI15), idem à 30,cm (SDI30), et irrigation à la raie avec des eaux usées (FW). Les résultats de cette recherche montrent que l'utilisation de filtres à sable dans DI et SDI a provoqué une diminution des index de pollution des eaux usées: 50,1% de la DBO5, 98,9% de la quantité totale, 97,6% des coliformes totaux, 93,2% des coliformes fécaux, 57,1% des nématodes, 81% de l'azote total, 52% de N-NO3, 84% de N-NH4 et 44% des matières en suspension. En outre l'application de SDI a entraîné une diminution de l'humidité de la surface du sol, ce qui a diminué les coliformes totaux et de coliformes fécaux en surface. Les valeurs moyennes pour ces paramètres n'ont révélé aucune différence significative (seuil 5%) entre les traitements SDI et FN. Les résultats de cette recherche ont également montré que avec SDI du fait d'une infiltration moindre, la contamination de prévalence (tels que le N-NO3) est minimisé du fait de l'utilisation des eaux usées en profondeur et des nappes phréatiques. En outre avec SDI les lessivages maximum de CE et de SAR ont été observées à 60,cm de profondeur alors qu'avec FW ce lessivage a été observé au-dessous de 90,cm. Copyright © 2008 John Wiley & Sons, Ltd. [source] Advances in powder diffraction pattern indexing: N-TREOR09JOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 5 2009Angela Altomare Powder pattern indexing can still be a challenge, despite the great recent advances in theoretical approaches, computer speed and experimental devices. More plausible unit cells, belonging to different crystal systems, are frequently found by the indexing programs, and recognition of the correct one may not be trivial. The task is, however, of extreme importance: in case of failure a lot of effort and computing time may be wasted. The classical figures of merit for estimating the unit-cell reliability {i.e.M20 [de Wolff (1968). J. Appl. Cryst.1, 108,113] and FN [Smith & Snyder (1979). J. Appl. Cryst.12, 60,65]} sometimes fail. For this reason, a new figure of merit has been introduced in N-TREOR09, the updated version of the indexing package N-TREOR [Altomare, Giacovazzo, Guagliardi, Moliterni, Rizzi & Werner (2000). J. Appl. Cryst. 33, 1180,1186], combining the information supplied by M20 with additional parameters such as the number of unindexed lines, the degree of overlap in the pattern (the so-called number of statistically independent observations), the symmetry deriving from the automatic evaluation of the extinction group, and the agreement between the calculated and observed profiles. The use of the new parameters requires a dramatic modification of the procedures used worldwide: in the approach presented here, extinction symbol and unit-cell determination are simultaneously estimated. N-TREOR09 benefits also from an improved indexing procedure in the triclinic system and has been integrated into EXPO2009, the updated version of EXPO2004 [Altomare, Caliandro, Camalli, Cuocci, Giacovazzo, Moliterni & Rizzi (2004). J. Appl. Cryst. 37, 1025,1028]. The application of the new procedure to a large set of test structures is described. [source] Association with replication between estrogen-related receptor , (ESRR,) Polymorphisms and bone phenotypes in women of European ancestryJOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2010Latifa Elfassihi Abstract Osteoporosis is a bone disease characterized by low bone mineral density (BMD), a highly heritable polygenic trait. Women are more prone than men to develop osteoporosis owing to a lower peak bone mass and accelerated bone loss at menopause. Lack of estrogen thus is a major risk factor for osteoporosis. In addition to having strong similarity to the estrogen receptor 1 (ESR1), the orphan nuclear estrogen-related receptor , (ESRR,) is widely expressed and shows overlap with ESR1 expression in tissues where estrogen has important physiologic functions. For these reasons, we have undertaken a study of ESRR, sequence variants in association with bone measurements [heel quantitative ultrasound (QUS) by measurements of broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI) and dual-energy X-ray absorptiometry (DXA) at the femoral neck (FN) and lumbar spine (LS)]. A silent variant was found to be associated with multiple bone measurements (LS, BUA, SOS, and SI), the p values ranging from .006 to .04 in a sample of 5144 Quebec women. The region of this variant was analyzed using the HapMap database and the Gabriel method to define a block of 20,kb. Using the Tagger method, eight TagSNPs were identified and genotyped in a sample of 1335 women. Four of these SNPs capture the five major block haplotypes. One SNP (rs2818964) and one haplotype were significantly associated with multiple bone measures. All SNPs involved in the associations were analyzed in two other sample sets with significant results in the same direction. These results suggest involvement of ESRR, in the determination of bone density in women. © 2010 American Society for Bone and Mineral Research [source] Risk Factors for Severity and Type of the Hip Fracture,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2009Jane A Cauley Abstract More severe hip fractures such as displaced femoral neck (FN) fractures and unstable intertrochanteric (IT) fractures lead to poorer outcomes, but risk factors for severe fractures have not been studied. To identify risk factors for severe types of hip fracture, we performed a prospective cohort study and obtained preoperative hip radiographs from women who sustained an incident hip fracture (excluding traumatic fractures). A single radiologist scored the severity of FN fractures by the Garden System: grades I and II, undisplaced; grades III and IV, displaced. The severity of IT hip fractures was rated by the Kyle System: grades I and II, stable; grades III and IV, unstable. A total of 249 women had FN fractures: 75 (30%) were undisplaced. A total of 213 women had IT fractures: 59 (28%) were stable. Both types of hip fracture increased with age, but older age was even more strongly associated with more severe hip fractures. Low BMD was more strongly related to undisplaced FN fractures (p interaction BMD × FN type, p = 0.0008) and stable IT fractures (p interaction BMD × IT type, p = 0.04). Similar findings were observed for estimated volumetric BMD and hip geometric parameters. Corticosteroid use was only associated with displaced FN fractures, and Parkinson's disease was only associated with stable IT fractures. Little difference was reported in the self-reported circumstances surrounding each type of fracture. In conclusion, the lower the BMD, the greater the likelihood of experiencing a hip fracture that is less displaced and more stable. [source] A Haplotype-Based Analysis of the LRP5 Gene in Relation to Osteoporosis Phenotypes in Spanish Postmenopausal Women,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2008Lídia Agueda Abstract LRP5 encodes the low-density lipoprotein receptor-related protein 5, a transmembrane protein involved in Wnt signaling. LRP5 is an important regulator of osteoblast growth and differentiation, affecting bone mass in vertebrates. Whether common variations in LRP5 are associated with normal BMD variation or osteoporotic phenotypes is of great relevance. We used a haplotype-based approach to search for common disease-associated variants in LRP5 in a cohort of 964 Spanish postmenopausal women. Twenty-four SNPs were selected, covering the LRP5 region, including the missense changes p.V667M and p.A1330V. The SNPs were genotyped and evaluated for association with BMD at the lumbar spine (LS) or femoral neck (FN) and with osteoporotic fracture, at single SNP and haplotype levels, by regression methods. Association with LS BMD was found for SNP 1, rs312009, located in the 5,-flanking region (p = 0.011, recessive model). SNP 6, rs2508836, in intron 1, was also associated with BMD, both at LS (p = 0.025, additive model) and FN (p = 0.031, recessive model). Two polymorphisms were associated with fracture: SNP 11, rs729635, in intron 1, and SNP 15, rs643892, in intron 5 (p = 0.007 additive model and p = 0.019 recessive model, respectively). Haplotype analyses did not provide additional information, except for haplotype "GC" of the block located at the 3,end of the gene. This haplotype spans intron 22 and the 3, untranslated region and was associated with FN BMD (p = 0.029, one copy of the haplotype versus none). In silico analyses showed that SNP 1 (rs312009) lies in a putative RUNX2 binding site. Electro-mobility shift assays confirmed RUNX2 binding to this site. [source] A Bivariate Whole Genome Linkage Study Identified Genomic Regions Influencing Both BMD and Bone Structure,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 11 2008Xiao-Gang Liu Abstract Areal BMD (aBMD) and areal bone size (ABS) are biologically correlated traits and are each important determinants of bone strength and risk of fractures. Studies showed that aBMD and ABS are genetically correlated, indicating that they may share some common genetic factors, which, however, are largely unknown. To study the genetic factors influencing both aBMD and ABS, bivariate whole genome linkage analyses were conducted for aBMD-ABS at the femoral neck (FN), lumbar spine (LS), and ultradistal (UD)-forearm in a large sample of 451 white pedigrees made up of 4498 individuals. We detected significant linkage on chromosome Xq27 (LOD = 4.89) for LS aBMD-ABS. In addition, we detected suggestive linkages at 20q11 (LOD = 3.65) and Xp11 (LOD = 2.96) for FN aBMD-ABS; at 12p11 (LOD = 3.39) and 17q21 (LOD = 2.94) for LS aBMD-ABS; and at 5q23 (LOD = 3.54), 7p15 (LOD = 3.45), Xq27 (LOD = 2.93), and 12p11 (LOD = 2.92) for UD-forearm aBMD-ABS. Subsequent discrimination analyses indicated that quantitative trait loci (QTLs) at 12p11 and 17q21 may have pleiotropic effects on aBMD and ABS. This study identified several genomic regions that may contain QTLs important for both aBMD and ABS. Further endeavors are necessary to follow these regions to eventually pinpoint the genetic variants affecting bone strength and risk of fractures. [source] Construction of the Femoral Neck During Growth Determines Its Strength in Old Age,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2007Roger M D Zebaze Abstract Study of the design of the FN in vivo in 697 women and in vitro in 200 cross-sections of different sizes and shapes along each of 13 FN specimens revealed that strength in old age was largely achieved during growth by differences in the distribution rather than the amount of bone material in a given FN cross-section from individual to individual. Introduction: We studied the design of the femoral neck (FN) to gain insight into the structural basis of FN strength in adulthood and FN fragility in old age. Materials and Methods: Studies in vivo were performed using densitometry in 697 women and in vitro using high-resolution ,CT and direct measurements in 13 pairs of postmortem specimens. Results: The contradictory needs of strength for loading yet lightness for mobility were met by varying FN size, shape, spatial distribution, and proportions of its trabecular and cortical bone in a cross-section, not its mass. Wider and narrower FNs were constructed with similar amounts of bone material. Wider FNs were relatively lighter: a 1 SD higher FN volume had a 0.67 (95% CI, 0.61,0.72) SD lower volumetric BMD (vBMD). A 1 SD increment in height was achieved by increasing FN volume by 0.32 (95% CI, 0.25,0.39) SD with only 0.15 (95% CI, 0.08,0.22) SD more bone, so taller individuals had a relatively lighter FN (vBMD was 0.13 [95% CI, 0.05,0.20 SD] SD lower). Greater periosteal apposition constructing a wider FN was offset by even greater endocortical resorption so that the same net amount of bone was distributed as a thinner cortex further from the neutral axis, increasing resistance to bending and lowering vBMD. This was recapitulated at each point along the FN; varying absolute and relative degrees of periosteal apposition and endocortical resorption focally used the same amount of material to fashion an elliptical FN of mainly cortical bone near the femoral shaft to offset bending but a more circular FN of proportionally more trabecular and less cortical bone to accommodate compressive loads adjacent to the pelvis. This structural heterogeneity was largely achieved by adaptive modeling and remodeling during growth,most of the variance in FN volume, BMC, and vBMD was growth related. Conclusions: Altering structural design while minimizing mass achieves FN strength and lightness. Bone fragility may be the result of failure to adapt bone's architecture to loading, not just low bone mass. [source] Recovery From Skeletal Fluorosis (an Enigmatic, American Case),,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2007Etah S Kurland Abstract A 52-year-old man presented with severe neck immobility and radiographic osteosclerosis. Elevated fluoride levels in serum, urine, and iliac crest bone revealed skeletal fluorosis. Nearly a decade of detailed follow-up documented considerable correction of the disorder after removal of the putative source of fluoride (toothpaste). Introduction: Skeletal fluorosis, a crippling bone disorder, is rare in the United States, but affects millions worldwide. There are no data regarding its reversibility. Materials and Methods: A white man presented in 1996 with neck immobility and worsening joint pains of 7-year duration. Radiographs revealed axial osteosclerosis. Bone markers were distinctly elevated. DXA of lumbar spine (LS), femoral neck (FN), and distal one-third radius showed Z scores of +14.3, +6.6, and ,0.6, respectively. Transiliac crest biopsy revealed cancellous volume 4.5 times the reference mean, cortical width 3.2 times the reference mean, osteoid thickness 25 times the reference mean, and wide and diffuse tetracycline uptake documenting osteomalacia. Fluoride (F) was elevated in serum (0.34 and 0.29 mg/liter [reference range: <0.20]), urine (26 mg/liter [reference range: 0.2,1.1 mg/liter]), and iliac crest (1.8% [reference range: <0.1%]). Tap and bottled water were negative for F. Surreptitious ingestion of toothpaste was the most plausible F source. Results: Monitoring for a decade showed that within 3 months of removal of F toothpaste, urine F dropped from 26 to 16 mg/liter (reference range: 0.2,1.1 mg/liter), to 3.9 at 14 months, and was normal (1.2 mg/liter) after 9 years. Serum F normalized within 8 months. Markers corrected by 14 months. Serum creatinine increased gradually from 1.0 (1997) to 1.3 mg/dl (2006; reference range: 0.5,1.4 mg/dl). Radiographs, after 9 years, showed decreased sclerosis of trabeculae and some decrease of sacrospinous ligament ossification. DXA, after 9 years, revealed 23.6% and 15.1% reduction in LS and FN BMD with Z scores of +9.3 and +4.8, respectively. Iliac crest, after 8.5 years, had normal osteoid surface and thickness with distinct double labels. Bone F, after 8.5 years, was 1.15% (reference range, <0.1), which was a 36% reduction (still 10 times the reference value). All arthralgias resolved within 2 years, and he never fractured, but new-onset nephrolithiasis occurred within 9 months and became a chronic problem. Conclusions: With removal of F exposure, skeletal fluorosis is reversible, but likely impacts for decades. Patients should be monitored for impending nephrolithiasis. [source] Smoking May Impair the Bone Protective Effects of Nutritional Calcium: A Population-Based Approach,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2003Joonas Sirola PhD Abstract Postmenopausal women were randomly selected to investigate the effects of smoking on prevention of bone loss with nutritional calcium. DXA was performed twice, and smoking and calcium intake habits were inquired through the mail in 954 women. Smoking dampened the bone protective effects of nutritional calcium. This may reflect the pathophysiology underlying smoking-induced bone loss postmenopause. This study evaluated the effect of smoking on the bone protective properties of nutritional calcium. Of the random sample of 954 peri- and postmenopausal women selected from the Osteoporosis Risk Factor and Prevention (OSTPRE) study cohort (n = 13,100) in Kuopio, Finland, 182 had smoked at some time (ever smokers) and 772 had never smoked. Women were divided in tertiles according to self-reported dairy nutritional calcium intake (mg/day): <648 (1st), 648-927 (2nd), >927 (3rd). Bone mineral density at lumbar spine (LS) and femoral neck (FN) was measured with DXA at baseline in 1989-1991 and at the 5-year follow-up in 1994-1997. In a linear regression model, nutritional calcium intake did not predict annual bone loss in smokers. These results were similar in the subanalysis on 71 current smokers (at both baseline and 5-year measurements) and on 85 past smokers. In never smokers, a statistically significant linear trend was observed between calcium intake and annual bone loss at LS, but at FN only after adjustment for age, weight, hormone replacement therapy (HRT), and other covariates. In analysis of covariance (ANCOVA), no differences in bone loss rate were observed between calcium intake tertiles among smokers. In nonsmokers, the annual bone loss rate was lower in the second (,0.41%) and the third (,0.35%) tertile compared with the first tertile (,0.61%) at LS (p < 0.05) and lower in the third tertile (,0.55%) than in first tertile (,0.72%) at FN after adjustment for age, weight, HRT, and other covariates (p < 0.05). When smokers were added to the nonsmoker group, the differences in bone loss rate between calcium intake tertiles disappeared. In addition, in ANCOVA, the term of interaction between smoking and calcium intake was statistically significant at LS only. In conclusion, smoking seems to impair the bone protective effects of nutritional calcium in postmenopausal women, more clearly in LS than FN. [source] A Randomized School-Based Jumping Intervention Confers Site and Maturity-Specific Benefits on Bone Structural Properties in Girls: A Hip Structural Analysis Study,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2002M. A. Petit Abstract We compared 7-month changes in bone structural properties in pre- and early-pubertal girls randomized to exercise intervention (10-minute, 3 times per week, jumping program) or control groups. Girls were classified as prepubertal (PRE; Tanner breast stage 1; n = 43 for intervention [I] and n = 25 for control [C]) or early-pubertal (EARLY; Tanner stages 2 and 3; n = 43 for I and n = 63 for C). Mean ± SD age was 10.0 ± 0.6 and 10.5 ± 0.6 for the PRE and EARLY groups, respectively. Proximal femur scans were analyzed using a hip structural analysis (HSA) program to assess bone mineral density (BMD), subperiosteal width, and cross-sectional area and to estimate cortical thickness, endosteal diameter, and section modulus at the femoral neck (FN), intertrochanter (IT), and femoral shaft (FS) regions. There were no differences between intervention and control groups for baseline height, weight, calcium intake, or physical activity or for change over 7 months (p > 0.05). We used analysis of covariance (ANCOVA) to examine group differences in changes of bone structure, adjusting for baseline weight, height change, Tanner breast stage, and physical activity. There were no differences in change for bone structure in the PRE girls. The more mature girls (EARLY) in the intervention group showed significantly greater gains in FN (+2.6%, p = 0.03) and IT (+1.7%, p = 0.02) BMD. Underpinning these changes were increased bone cross-sectional area and reduced endosteal expansion. Changes in subperiosteal dimensions did not differ. Structural changes improved section modulus (bending strength) at the FN (+4.0%, p = 0.04), but not at the IT region. There were no differences at the primarily cortical FS. These data provide insight into geometric changes that underpin exercise-associated gain in bone strength in early-pubertal girls. [source] Heterogeneity in the Growth of the Axial and Appendicular Skeleton in Boys: Implications for the Pathogenesis of Bone Fragility in MenJOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2000Michelle Bradney Abstract Men with spine fractures have reduced vertebral body (VB) volume and volumetric bone mineral density (vBMD). Men with hip fractures have reduced femoral neck (FN) volume and vBMD, site-specific deficits that may have their origins in growth. To describe the tempo of growth in regional bone size, bone mineral content (BMC), and vBMD, we measured bone length, periosteal and endocortical diameters, BMC, and vBMD using dual-energy X-ray absorptiometry in 184 boys aged between 7 and 17 years. Before puberty, growth was more rapid in the legs than in the trunk. During puberty, leg growth slowed while trunk length accelerated. Bone size was more advanced than BMC in all regions, being ,70% and ,35% of their predicted peaks at 7 years of age, respectively. At 16 years of age, bone size had reached its adult peak while BMC was still 10% below its predicted peak. The legs accounted for 48%, whereas the spine accounted for 10%, of the 1878 g BMC accrued between 7 and 17 years. Peripubertal growth contributed (i) 55% of the increase in leg length but 78% of the mineral accrued and (ii) 69% of the increase in spine length but 87% of the mineral accrued. Increased metacarpal and midfemoral cortical thickness was caused by respective periosteal expansion with minimal change in the endocortical diameter. Total femur and VB vBMD increased by 30,40% while size and BMC increased by 200,300%. Thus, growth builds a bigger but only slightly denser skeleton. We speculate that effect of disease or a risk factor during growth depends on the regions maturational stage at the time of exposure. The earlier growth of a regions size than mass, and the differing growth patterns from region to region, predispose to site-specific deficits in bone size, vBMD, or both. Regions further from their peak may be more severely affected by illness than those nearer completion of growth. Bone fragility in old age is likely to have its foundations partly established during growth. [source] B-type natriuretic peptide and extracellular matrix protein interactions in human cardiac fibroblastsJOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2010Brenda K. Huntley Cardiac fibroblasts (CFs) regulate myocardial remodeling by proliferating, differentiating, and secreting extracellular matrix (ECM) proteins. B-type natriuretic peptide (BNP) is anti-fibrotic, inhibits collagen production, augments matrix metalloproteinases, and suppresses CF proliferation. Recently, we demonstrated that the ECM protein fibronectin (FN) augmented production of BNP's second messenger, 3,, 5, cyclic guanosine monophosphate (cGMP) in CFs, supporting crosstalk between FN, BNP, and its receptor, natriuretic peptide receptor A (NPR-A). Here, we address the specificity of FN to augment cGMP generation by investigating other matrix proteins, including collagen IV which contains RGD motifs and collagen I and poly- L -lysine, which have no RGD domain. Collagen IV showed increased cGMP generation to BNP similar to FN. Collagen I and poly- L -lysine had no effect. As FN also interacts with integrins, we then examined the effect of integrin receptor antibody blockade on BNP-mediated cGMP production. On FN plates, antibodies blocking RGD-binding domains of several integrin subtypes had little effect, while a non-RGD domain interfering integrin ,v,3 antibody augmented cGMP production. Further, on uncoated plates, integrin ,v,3 blockade continued to potentiate the BNP/cGMP response. These studies suggest that both RGD containing ECM proteins and integrins may interact with BNP/NPR-A to modulate cGMP generation. J. Cell. Physiol. 225: 251,255, 2010. © 2010 Wiley-Liss, Inc. [source] Cross-talk between the insulin-like growth factor (IGF) axis and membrane integrins to regulate cell physiologyJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2010James Beattie The biology of cross-talk between activated growth factor receptors and cell-surface integrins is an area which has attracted much interest in recent years (Schwartz and Ginsberg, 2002). This review discusses the relationship between the insulin-like growth factor (IGF) axis and cell-surface integrin receptors in the regulation of various aspects of cell physiology. Key to these interactions are signals transmitted between integrins and the IGF-I receptor (IGF-IR) when either or both are bound to their cognate ligands and we will review the current state of knowledge in this area. The IGF axis comprises many molecular components and we will also discuss the potential role of these species in cross-talk with the integrin receptor. With respect to integrin ligands, we will mainly focus on the well-characterized interactions of the two extracellular matrix (ECM) glycoproteins fibronectin (FN) and vitronectin (VN) with cell-surface ligands, and, how this affects activity through the IGF axis. However, we will also highlight the importance of other integrin activation mechanisms and their impact on IGF activity. J. Cell. Physiol. 224: 605,611, 2010. © 2010 Wiley-Liss, Inc. [source] Continuous requirement for pp60-Src and phospho-paxillin during fibronectin matrix assembly by transformed cellsJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2007Iwona Wierzbicka-Patynowski Fibronectin (FN) matrix assembly is an integrin-mediated process that is regulated by both the extracellular environment and intracellular signaling pathways. The activity of Src-family kinases is important for initiation of FN assembly by normal fibroblasts. Here we report that in HT1080 fibrosarcoma cells, Src kinase activity is required not only for the assembly of FN matrix but also for the maintenance of FN matrix fibrils at the cell surface. Dexamethasone-induced FN fibril formation by these cells was completely blocked for at least 24 h when Src-family kinase activity was inhibited by either PP1 or SU6656. Inhibition of Src after significant matrix had already been assembled, resulted in an increased rate of loss of detergent-insoluble FN. Binding of activation-dependent integrin antibodies reveals a role for Src in maintaining integrin activity. The requirement for Src kinase activity appears to depend, in part, on phosphorylation of paxillin at tyrosine 118 (Y118). Phospho-paxillin co-localized with FN fibrils, and overexpression of GFP-paxillin but not of GFP-paxillinY118F enhanced cell-mediated assembly of FN. Our results indicate that Src maintains FN matrix at the cell surface through its effect on integrin activity and paxillin phosphorylation. J. Cell. Physiol. 210: 750,756, 2007. © 2006 Wiley-Liss, Inc. [source] BNP-induced activation of cGMP in human cardiac fibroblasts: Interactions with fibronectin and natriuretic peptide receptorsJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2006Brenda K. Huntley Cardiac remodeling involves the accumulation of extracellular matrix (ECM) proteins including fibronectin (FN). FN contains RGD motifs that bind integrins at DDX sequences allowing signaling from the ECM to the nucleus. We noted that the natriuretic peptide receptor A (NPR-A) sequence contains both RGD and DDX sequences. The goal of the current investigation was to determine potential interactions between FN and NPR-A on BNP induction of cGMP in cultured human cardiac fibroblasts (CFs). Further, we sought to determine whether a Mayo designed NPR-A specific RGD peptide could modify this interaction. Here we reconfirm the presence of all three natriuretic peptide receptors (NPR) in CFs. CFs plated on FN demonstrated a pronounced increase in cGMP production to BNP compared to non-coated plates. This production was also enhanced by the NPR-A specific RGD peptide, which further augmented FN associated cGMP production. Addition of HS-142-1, a NPR-A/B antagonist, abrogated the responses of BNP to both FN and the NPR-A specific RGD peptide. Finally, we defined a possible role for the NPR-C through non-cGMP mechanisms in mediating the anti-proliferative actions of BNP in CFs where the NPR-C antagonist cANF 4-28 but not HS-142-1 blocked BNP-mediated inhibition of proliferation of CFs. We conclude that NPR-A interacts with components of the ECM such as FN to enhance BNP activation of cGMP and that a small NPR-A specific RGD peptide augments this action of BNP with possible therapeutic implications. Lastly, the NPR-C may also have a role in mediating anti-proliferative actions of BNP in CFs. J. Cell. Physiol. 209: 943,949, 2006. © 2006 Wiley-Liss, Inc. [source] Evaluation of the Sysmex Xe-2100® hematology analyzer in hospital useJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 4 2003Danièle Nakul-Aquaronne Abstract The Sysmex XE-2100® (Sysmex Corp. Kobe, Japan) is a latest-generation hematology analyzer. Its optical and electrical measuring technology is improved by the addition of flux cytometry, fluorescence, and differential lysis. Its analytical performance in terms of precision, reproducibility, linearity, carryover, and time stability was found to be entirely satisfactory. In addition, the results of 500 complete blood counts and differentials correlated perfectly with those obtained by the Coulter STKS® (Beckman Coulter, Villapointe, France). The comparison of 500 leukocyte differential count results analyzed in parallel with optical microscopy and the XE-2100® were surprising, and favorable to the XE-2100®. This analyzer provides the user with an undeniable feeling of security concerning its reliability in detecting and identifying anomalies in the automated leukocyte differential count. With a sensitivity of 96%, a negative predictive value (NPV) of 98%, and a false-negative (FN) rate of 4%, the XE-2100® has perhaps reached the technological limits for a machine performing morphological recognition of normal and pathological blood cells. J. Clin. Lab. Anal. 17:113,123, 2003. © 2003 Wiley-Liss, Inc. [source] Time-dependent density functional theory study on the electronic excited-state geometric structure, infrared spectra, and hydrogen bonding of a doubly hydrogen-bonded complexJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 16 2009Yufang Liu Abstract The geometric structures and infrared (IR) spectra in the electronically excited state of a novel doubly hydrogen-bonded complex formed by fluorenone and alcohols, which has been observed by IR spectra in experimental study, are investigated by the time-dependent density functional theory (TDDFT) method. The geometric structures and IR spectra in both ground state and the S1 state of this doubly hydrogen-bonded FN-2MeOH complex are calculated using the DFT and TDDFT methods, respectively. Two intermolecular hydrogen bonds are formed between FN and methanol molecules in the doubly hydrogen-bonded FN-2MeOH complex. Moreover, the formation of the second intermolecular hydrogen bond can make the first intermolecular hydrogen bond become slightly weak. Furthermore, it is confirmed that the spectral shoulder at around 1700 cm,1 observed in the IR spectra should be assigned as the doubly hydrogen-bonded FN-2MeOH complex from our calculated results. The electronic excited-state hydrogen bonding dynamics is also studied by monitoring some vibraitonal modes related to the formation of hydrogen bonds in different electronic states. As a result, both the two intermolecular hydrogen bonds are significantly strengthened in the S1 state of the doubly hydrogen-bonded FN-2MeOH complex. The hydrogen bond strengthening in the electronically excited state is similar to the previous study on the singly hydrogen-bonded FN-MeOH complex and play important role on the photophysics of fluorenone in solutions. © 2009 Wiley Periodicals, Inc. J Comput Chem 2009 [source] |