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1

UVB radiation and human monocyte accessory function: Differential effects on pre-mitotic events in T-cell activation  

SciTech Connect

Purified T lymphocytes fail to proliferate in response to antigenic and mitogenic stimuli when cultured in the presence of accessory cells that have been exposed in vitro to sublethal doses of UVB radiation. Because proliferation represents a final stage in the T-cell activation process, the present study was conducted to determine whether T cells were able to progress through any of the pre-mitotic stages when UVB-irradiated monocytes were used as model accessory cells. In these experiments, monoclonal anti-CD3 antibodies were employed as the mitogenic stimulus. Culture of T cells with UVB-irradiated monocytes did allow the T cells to undergo an increase in intracellular free calcium, which is one of the first steps in the activation sequence. The T cells expressed interleukin-2 receptors, although at a reduced level. However, T cells failed to produce interleukin-2 above background levels when they were placed in culture with monocytes exposed to UVB doses as low as 50 J/m2. Incubation of T cells with UVB-irradiated monocytes did not affect the subsequent capacity of T cells to proliferate, since they developed a normal proliferative response in secondary culture when restimulated with anti-CD3 antibodies and unirradiated monocytes. These studies indicate that T lymphocytes become partially activated when cultured with UVB-irradiated monocytes and mitogenic anti-CD3 monoclonal antibodies. In addition, they suggest that interleukin-2 production is the T-cell activation step most sensitive to inhibition when UVB-irradiated monocytes are employed as accessory cells.

Krutmann, J.K.; Kammer, G.M.; Toossi, Z.; Waller, R.L.; Ellner, J.J.; Elmets, C.A. (Case Western Reserve Univ., Cleveland, OH (USA))

1990-02-01

2

Accessory cell function of Th2 clones.  

PubMed

We have investigated the ability of T helper clones to serve as accessory cells and in the presence of mitogen activate freshly-isolated, splenic T cells. In this type of costimulatory assay, the Th cells that secrete IL-4 but not the Th cells that secrete IL-2 function as AC to induce T cell proliferation in the presence of various T cell mitogens (Con A, anti-CD3 mAb, anti-TCR mAb, and anti-Thy-1 mAb). The signal provided by the accessory Th2 cells occurred independently of MHC restriction, and the analysis of dose-response curves showed the involvement of a single stimulator cell. CD4, as well as CD8 expressing splenic T cells were induced to proliferate by the Th2 clones and mitogen, but mAb specific for CD4 or CD8 failed to affect the response. These findings indicate that cloned Th2 cells functioned as accessory cells and induced naive T cells to proliferate in the presence of mitogen. PMID:2528580

Evavold, B D; Quintans, J

1989-09-15

3

Postnatal and adult exposure to estradiol differentially influences adult neurogenesis in the main and accessory olfactory bulb of female mice  

PubMed Central

Neurons incorporated into the adult main olfactory bulb (MOB) and accessory olfactory bulb (AOB) derive from the subventricular zone (SVZ). Despite some recent studies on the role of olfactory neurogenesis in sociosexual behaviors mediated by hormones, data on the implication of estrogens are still lacking. Taking advantage of female aromatase-knockout (ArKO) mice, which are unable to produce estradiol across their life span, we investigated the role of estradiol exposure during early postnatal and adult periods on adult neurogenesis in the MOB and AOB. We found that proliferation of progenitor cells in the adult female SVZ was not influenced by estradiol. However, whereas adult exposure to estradiol influences the turnover of MOB newborn neurons, the survival of those in the AOB depends on exposure to estradiol during the early postnatal period. Finally, based on their expression of Zif268, we showed that newborn neurons in the MOB responded to sociosexual odors, albeit to a lesser extent in ArKO females, suggesting a contribution of estradiol during the early postnatal period to this response. Together, these results suggest that the survival and functional integration of newborn neurons in the adult female MOB and AOB are differentially influenced by estrogens from the early postnatal period to adulthood.—Veyrac, A., Bakker, J. Postnatal and adult exposure to estradiol differentially influences adult neurogenesis in the main and accessory olfactory bulb of female mice.

Veyrac, Alexandra; Bakker, Julie

2011-01-01

4

Carcinoembryonic antigen functions as an accessory adhesion molecule mediating colon epithelial cell-collagen interactions.  

PubMed Central

We have previously shown that a human colon carcinoma cell line (SW1222) expresses a collagen receptor recognizing the Arg-Gly-Asp tripeptide sequence found in collagen. This receptor mediates the cellular attachment to collagen and, subsequently, the glandular differentiation seen in a three-dimensional collagen gel culture. In a search to identify cell surface molecules mediating the adhesion and differentiation of SW1222 cells, we have screened a panel of monoclonal antibodies recognizing epithelial cell surface determinants for their ability to inhibit the collagen binding of SW1222 cells. We have found that four monoclonal antibodies recognizing the 180-kDa carcinoembryonic antigen (CEA) glycoprotein and other members of the CEA family inhibited (up to 87%) the binding of SW1222 cells to type I collagen matrix. Using a cell attachment assay, we have not detected any direct collagen binding of either purified CEA or another CEA-expressing human colon carcinoma cell line (LS174T). These data suggest that CEA is not a collagen-binding protein itself but is likely to be associated with the functional Arg-Gly-Asp collagen receptor expressed by SW1222 cells. We suggest that CEA may function as an accessory molecule, controlling the functional activity of the SW1222 collagen receptor. Images

Pignatelli, M; Durbin, H; Bodmer, W F

1990-01-01

5

Segregated pathways to the vomeronasal amygdala: differential projections from the anterior and posterior divisions of the accessory olfactory bulb.  

PubMed

Apically and basally located receptor neurons in the vomeronasal sensory epithelium express G(i2 alpha)- and G(o alpha)-proteins, V1R and V2R vomeronasal receptors, project to the anterior and posterior accessory olfactory bulb and respond to different stimuli, respectively. The extent to which secondary projections from the two portions of the accessory olfactory bulb are convergent in the vomeronasal amygdala is controversial. This issue is addressed by using anterograde and retrograde tract-tracing methods in rats including electron microscopy. Injections of dextran-amines, Fluoro Gold, cholera toxin-B subunit and Fast Blue were delivered to the anterior and posterior accessory olfactory bulb, bed nucleus of the stria terminalis, dorsal anterior amygdala and bed nucleus of the accessory olfactory tract/anteroventral medial amygdaloid nucleus. We have demonstrated that, apart from common vomeronasal-recipient areas, only the anterior accessory olfactory bulb projects to the bed nucleus of the stria terminalis, medial division, posteromedial part, and only the posterior accessory olfactory bulb projects to the dorsal anterior amygdala and deep cell layers of the bed nucleus of the accessory olfactory tract and the anteroventral medial amygdaloid nucleus. These results provide evidence that, excluding areas of convergence, the V1R and V2R vomeronasal pathways project to specific areas of the amygdala. These two vomeronasal subsystems are therefore anatomically and functionally separated in the telencephalon. PMID:17419754

Mohedano-Moriano, Alicia; Pro-Sistiaga, Palma; Ubeda-Bañón, Isabel; Crespo, Carlos; Insausti, Ricardo; Martinez-Marcos, Alino

2007-04-01

6

Differential Symmetric Functions  

Microsoft Academic Search

A (generalized) Wronskian is a determinant of the form det$ [D^{\\\\alpha_i} x_j]_{1 \\\\leq i, j \\\\leq n} $, where D is the differential operator. Wronskians are differential analogs of alternants. Imitating Jacobi's definition of Schur functions as quotients of two alternants, we define differential Schur functions as quotients of two Wronskians. Differential Schur functions are absolute invariants of the general

Joseph P. S. Kung

2000-01-01

7

Probing the function of Drosophila melanogaster accessory glands by directed cell ablation.  

PubMed Central

The female Drosophila melanogaster fly undergoes behavioral changes after mating, including an increase in egg laying and an avoidance of remating. Accessory-gland products elicit these changes transiently when introduced into unmated female flies. We report here the generation and phenotype of flies that lack functional accessory-gland main cells as a consequence of genetically directed delivery of diphtheria toxin subunit A to those cells. Only main-cell secretions are essential for the short-term inhibition to remating; no other products of the genital tract can replace their function. Long-term inhibition to remating depends only on the storage of sperm in the female. Both sperm and main-cell secretions have roles in the increase of egg laying by the mated female. In addition to full-strength diphtheria toxin, we used low-activity toxins to kill only those cells that express toxin at high levels. These transgenic strains that express diphtheria toxins of different strengths in accessory-gland main cells will be useful in further defining the role of these cells. Images Fig. 1 Fig. 2

Kalb, J M; DiBenedetto, A J; Wolfner, M F

1993-01-01

8

Ventricular Dyssynchrony and Function Improve following Catheter Ablation of Nonseptal Accessory Pathways in Children  

PubMed Central

Introduction. Paradoxical or hypokinetic interventricular septal motion has been described in patients with septal or paraseptal accessory pathways. Data regarding nonseptal pathways is limited. Methods and Results. We quantified left ventricular dyssynchrony and function in 16 consecutive children, 14.2 ± 3.7 years, weighing 53 ± 17?kg, prior to and following catheter ablation of bidirectional septal (N = 6) and nonseptal (N = 10) accessory pathways. Following ablation, the left ventricular ejection fraction increased by 4.9 ± 2.1% (P = 0.038) from a baseline value of 57.0% ± 7.8%. By tissue Doppler imaging, the interval between QRS onset and peak systolic velocity (Ts) decreased from a median of 33.0?ms to 18.0?ms (P = 0.013). The left ventricular ejection fraction increased to a greater extent following catheter ablation of nonseptal (5.9% ± 2.6%, P = 0.023) versus septal (2.5% ± 4.1%, P = 0.461) pathways. The four patients with an ejection fraction <50%, two of whom had left lateral pathways, improved to >50% after ablation. Similarly, the improvement in dyssynchrony was more marked in patients with nonseptal versus septal pathways (difference between septal and lateral wall motion delay before and after ablation 20.6 ± 7.1?ms (P = 0.015) versus 1.4 ± 11.4?ms (P = 0.655)). Conclusion. Left ventricular systolic function and dyssynchrony improve after ablation of antegrade-conducting accessory pathways in children, with more pronounced changes noted for nonseptal pathways.

Abadir, Sylvia; Fournier, Anne; Dubuc, Marc; Sarquella-Brugada, Georgia; Garceau, Patrick

2013-01-01

9

Differential Localization of the Streptococcal Accessory Sec Components and Implications for Substrate Export  

PubMed Central

The accessory Sec system of Streptococcus gordonii is comprised of SecY2, SecA2, and five proteins (Asp1 through -5) that are required for the export of a serine-rich glycoprotein, GspB. We have previously shown that a number of the Asps interact with GspB, SecA2, or each other. To further define the roles of these Asps in export, we examined their subcellular localization in S. gordonii and in Escherichia coli expressing the streptococcal accessory Sec system. In particular, we assessed how the locations of these accessory Sec proteins were altered by the presence of other components. Using fluorescence microscopy, we found in E. coli that SecA2 localized within multiple foci at the cell membrane, regardless of whether other accessory Sec proteins were expressed. Asp2 alone localized to the cell poles but formed a similar punctate pattern at the membrane when SecA2 was present. Asp1 and Asp3 localized diffusely in the cytosol when expressed alone or with SecA2. However, these proteins redistributed to the membrane in a punctate arrangement when all of the accessory Sec components were present. Cell fractionation studies with S. gordonii further corroborated these microscopy results. Collectively, these findings indicate that Asp1 to -3 are not integral membrane proteins that form structural parts of the translocation channel. Instead, SecA2 serves as a docking site for Asp2, which in turn attracts a complex of Asp1 and Asp3 to the membrane. These protein interactions may be important for the trafficking of GspB to the cell membrane and its subsequent translocation.

Yen, Yihfen T.; Cameron, Todd A.; Bensing, Barbara A.; Seepersaud, Ravin; Zambryski, Patricia C.

2013-01-01

10

Localization and function of the accessory protein Mfa3 in Porphyromonas gingivalis Mfa1 fimbriae.  

PubMed

The fimbriae of Porphyromonas gingivalis, the causative agent of periodontitis, have been implicated in various aspects of pathogenicity, such as colonization, adhesion and aggregation. Porphyromonas gingivalis ATCC 33277 has two adhesins comprised of the FimA and Mfa1 fimbriae. We characterized the PGN0289 (Mfa3) protein, which is one of the three accessory proteins of Mfa1 fimbriae in P. gingivalis. The Mfa3 protein was present in two different sizes, 40 and 43 kDa, in the cell. The 43-kDa and 40-kDa Mfa3 were detected largely in the inner membrane and the outer membrane, respectively. Purified Mfa1 fimbriae contained the 40-kDa Mfa3 alone. Furthermore, the 40-kDa Mfa3 started with the Ala(44) residue of the deduced amino acid sequence, indicating that the N-terminal region of the nascent protein expressed from the mfa3 gene is processed in the transport step from the inner membrane into fimbriae. Immuno-electron microscopy revealed that Mfa3 localized at the tip of the fimbrial shaft. Interestingly, deletion of the mfa3 gene resulted in the absence of other accessory proteins, PGN0290 and PGN0291, in the purified Mfa1 fimbriae, suggesting that Mfa3 is required for integration of PGN0290 and PGN0291 into fimbriae. A double mutant of mfa3 and fimA genes (phenotype Mfa1 plus, FimA minus) showed increased auto-aggregation and biofilm formation similar to a double mutant of mfa1 and fimA genes (phenotype Mfa1(-) , FimA(-) ). These findings suggest that the tip protein Mfa3 of the Mfa1 fimbriae may function in the integration of accessory proteins and in the colonization of P. gingivalis. PMID:24118823

Hasegawa, Y; Nagano, K; Ikai, R; Izumigawa, M; Yoshida, Y; Kitai, N; Lamont, R J; Murakami, Y; Yoshimura, F

2013-10-05

11

Matching Accessories  

NSDL National Science Digital Library

Heterodimerization enhances the complexity of ligand recognition and diversity of signaling responses of heterotrimeric guanine nucleotide-binding protein-coupled receptors (GPCRs). Many accessory proteins (for ion channels or GPCRs) appear to associate with their partners relatively early in the process whereby proteins are transported to the cell surface; their roles in modulating function may have evolved out of simple proximity to a protein that once upon a time they either facilitated or accompanied through the maturation process. The receptor activity-modifying proteins (RAMPs) are a family of single-transmembrane accessory proteins that heterodimerize with GPCRs and, thereby, allow individual GPCRs to recognize multiple ligands and to activate various signaling pathways in response to ligand binding. The M10 family of major histocompatibility complex (MHC) class 1b proteins has recently been shown to associate with murine vomeronasal V2R receptors, as well as to escort them to the cell surface. The exact role of M10 in modulating V2R function (or vice versa) remains to be determined.

Steven M. Foord (Stevenage;Target Bioinformatics, GlaxoSmithKline Medicine Research Centre REV)

2003-07-08

12

Cloning, Expression, and Functional Characterization of the Equine Herpesvirus 1 DNA Polymerase and Its Accessory Subunit  

PubMed Central

We report the expression and characterization of the putative catalytic subunit (pORF30) and accessory protein (pORF18) of equine herpesvirus 1 DNA polymerase, which are encoded by open reading frames 30 and 18 and are homologous to herpes simplex virus type 1 UL30 and UL42, respectively. In vitro transcription-translation of open reading frames 30 and 18 generated proteins of 136 and 45 kDa, respectively. In vitro-expressed pORF30 possessed basal DNA polymerase activity that was stimulated by pORF18, as measured by DNA polymerase assays in vitro. Purified baculovirus-expressed pORF30 exhibited DNA polymerase activity similar to that of the in vitro-expressed protein, and baculovirus-expressed pORF18 could stimulate both nucleotide incorporation and long-chain DNA synthesis by pORF30 in a dose- and time-dependent manner. The salt optima for activity of both pORF30 and the holoenzyme were substantially different from those for other herpesvirus DNA polymerases. As demonstrated by yeast two-hybrid assays, pORF30 and pORF18 could physically interact, most likely with a 1:1 stoichiometry. Finally, by mutational analysis of the 1,220-residue pORF30, we demonstrated that the extreme C terminus of pORF30 is important for physical and functional interaction with the accessory protein, as reported for UL30 and other herpesvirus DNA polymerases. In addition, a C-proximal region of pORF30, corresponding to residues 1114 to 1172, is involved in binding to, and stimulation by, pORF18. Taken together, the results indicate that pORF30 and pORF18 are the equine herpesvirus 1 counterparts of herpes simplex virus type 1 UL30 and UL42 and share many, but not all, of their characteristics.

Loregian, Arianna; Case, Alessandro; Cancellotti, Enrico; Valente, Carlo; Marsden, Howard S.; Palu, Giorgio

2006-01-01

13

Ultra violet radiation-induced defects in accessory cell function in the human proliferative response to tetanus.  

PubMed Central

Ultraviolet B radiation (290-320 nm) has been shown to interfere with accessory cell function of human peripheral blood mononuclear cells in the generation of a proliferative response to tetanus. By altering the timing of irradiation of adherent cells and using short pulses of antigen, we have identified a minimum of two u.v. sensitive accessory cell functions. The first involves antigen presentation and is not readily reversible with time in culture after irradiation. The second is demonstrated by the ability of low doses of u.v. radiation given after the tetanus toxoid pulse to inhibit an event(s) occurring independent of antigen processing. Both occur within a range of doses which would penetrate to the vasculature of the skin of humans exposed to the sun or to phototherapy.

Pretell, J O; Wimberly, J; Parrish, J A

1984-01-01

14

SURGICAL ANATOMY OF SPINAL ACCESSORY NERVE: IS TRAPEZIUS FUNCTIONAL DEFICIT INEVITABLE AFTER DIVISION OF THE NERVE?  

Microsoft Academic Search

The course of spinal accessory nerve in the posterior triangle, the innervation of the sternocleidomastoid and trapezius muscles and the contributions from the cervical plexus were studied in 20 cadaveric dissections. The nerve was most vulnerable to iatrogenic injuries after leaving the sternocleidomastoid. Direct innervation of trapezius by cervical plexus branches was noted in five dissections, whereas connections between the

Z. H. DAILIANA; H. MEHDIAN; A. GILBERT

2001-01-01

15

Functional organization of olfactory processing in the accessory lobe of the spiny lobster  

Microsoft Academic Search

An isolated brain preparation was used to characterize neurons innervating the accessory lobe (AL) of the spiny lobster (Panulirus argus). Four distinct classes of neurons responded to electrical stimulation of the olfactory (antennular) nerve. These cells responded to electrical stimulation with a long and variable latency; they also responded to odor stimulation in a nose-brain preparation. Neurons connecting the AL

M. Wachowiak; C. E. Diebel; B. W. Ache

1996-01-01

16

Electrocardiographic differentiation of typical atrioventricular node reentrant tachycardia from atrioventricular reciprocating tachycardia mediated by concealed accessory pathway in children.  

PubMed

The value of the electrocardiogram (ECG) in children with supraventricular tachycardia (SVT) is unclear. The noninvasive differentiation of typical atrioventricular node reentrant tachycardia (AVNRT) and atrioventricular reciprocating tachycardia (AVRT) mediated by concealed accessory pathway conduction is clinically important, as it helps in counseling and potentially facilitates ablation procedures. One hundred forty-eight ECGs showing narrow QRS complex SVT were obtained from children before successful radiofrequency catheter ablation. An initial 102 ECGs were analyzed by 3 blinded observers to assess the utility of various electrocardiographic findings. No electrocardiographic criteria were found to discriminate between SVT mechanisms on 1- to 3-channel Holter/event recorder tracings (n = 32); their interpretation mainly (55%) resulted in an incorrect SVT diagnosis. On 12-lead ECGs (n = 70), the 2 arrhythmias were accurately diagnosed in 76% of patients; 5 findings were found to be discriminators of tachycardia mechanism. Predictors of AVRT were visible P waves in 74% of cases (sensitivity 92%; specificity 64%), RP intervals of > or =100 ms in 91% (sensitivity 84%; specificity 91%), and ST-segment depression of > or =2 mm in 73% of cases (sensitivity 52%; specificity 82%). Pseudo r' waves in lead V(1) and pseudo S waves in the inferior leads during tachycardia predicted AVNRT in 100% of cases (sensitivity 55% and 20%, respectively; specificity 100% for both). Based on these results, we developed a new diagnostic 12-lead electrocardiographic algorithm for pseudo r'/S waves, RP duration, and ST-segment depression during tachycardia. Two observers tested the algorithm in 46 (21 AVNRT; 25 AVRT) additional cases; they correctly diagnosed the SVT mechanism in 91% and 87%, respectively. Thus, the stepwise use of diagnostically relevant 12-lead electrocardiographic parameters helps to more accurately differentiate mechanisms of reentrant SVT. PMID:12714151

Jaeggi, Edgar T; Gilljam, Thomas; Bauersfeld, Urs; Chiu, Christine; Gow, Robert

2003-05-01

17

Loss of function of the melanocortin 2 receptor accessory protein 2 is associated with mammalian obesity.  

PubMed

Melanocortin receptor accessory proteins (MRAPs) modulate signaling of melanocortin receptors in vitro. To investigate the physiological role of brain-expressed melanocortin 2 receptor accessory protein 2 (MRAP2), we characterized mice with whole-body and brain-specific targeted deletion of Mrap2, both of which develop severe obesity at a young age. Mrap2 interacts directly with melanocortin 4 receptor (Mc4r), a protein previously implicated in mammalian obesity, and it enhances Mc4r-mediated generation of the second messenger cyclic adenosine monophosphate, suggesting that alterations in Mc4r signaling may be one mechanism underlying the association between Mrap2 disruption and obesity. In a study of humans with severe, early-onset obesity, we found four rare, potentially pathogenic genetic variants in MRAP2, suggesting that the gene may also contribute to body weight regulation in humans. PMID:23869016

Asai, Masato; Ramachandrappa, Shwetha; Joachim, Maria; Shen, Yuan; Zhang, Rong; Nuthalapati, Nikhil; Ramanathan, Visali; Strochlic, David E; Ferket, Peter; Linhart, Kirsten; Ho, Caroline; Novoselova, Tatiana V; Garg, Sumedha; Ridderstråle, Martin; Marcus, Claude; Hirschhorn, Joel N; Keogh, Julia M; O'Rahilly, Stephen; Chan, Li F; Clark, Adrian J; Farooqi, I Sadaf; Majzoub, Joseph A

2013-07-19

18

Loss of Function of the Melanocortin 2 Receptor Accessory Protein 2 Is Associated with Mammalian Obesity  

PubMed Central

Melanocortin receptor accessory proteins (MRAPs) modulate signaling of melanocortin receptors in vitro. To investigate the physiological role of brain-expressed Melanocortin 2 Receptor Accessory Protein 2 (MRAP2), we characterized mice with whole body and brain-specific targeted deletion of Mrap2, both of which develop severe obesity at a young age. Mrap2 interacts directly with Melanocortin 4 Receptor (Mc4r), a protein previously implicated in mammalian obesity, and it enhances Mc4r-mediated generation of the second messenger cyclic AMP, suggesting that alterations in Mc4r signaling may be one mechanism underlying the association between Mrap2 disruption and obesity. In a study of humans with severe, early-onset obesity, we found four rare, potentially pathogenic genetic variants in MRAP2, suggesting that the gene may also contribute to body weight regulation in humans.

Asai, Masato; Ramachandrappa, Shwetha; Joachim, Maria; Shen, Yuan; Zhang, Rong; Nuthalapati, Nikhil; Ramanathan, Visali; Strochlic, David E.; Ferket, Peter; Linhart, Kirsten; Ho, Caroline; Novoselova, Tatiana V.; Garg, Sumedha; Ridderstrale, Martin; Marcus, Claude; Hirschhorn, Joel N.; Keogh, Julia M.; O'Rahilly, Stephen; Chan, Li F.; Clark, Adrian J.; Farooqi, I. Sadaf; Majzoub, Joseph A.

2013-01-01

19

Receptor accessory folding helper enzymes: the functional role of peptidyl prolyl cis\\/ trans isomerases  

Microsoft Academic Search

Receptor accessory peptidyl prolyl cis\\/trans isomerases (PPIases) of the FKBP and cyclophilin types form receptor heterocomplexes with different stabilities. PPIases have been found to associate with other receptor heterocomplex constituents via either proline-directed active sites or additional domains of the enzymes. The single-domain PPIases FKBP12 and FKBP12.6 are shown to interact with receptor protein kinases and calcium channels at their

Cordelia Schiene-Fischer; Chao Yu

2001-01-01

20

Shared and differential traits in the accessory olfactory bulb of caviomorph rodents with particular reference to the semiaquatic capybara  

PubMed Central

The vomeronasal system is crucial for social and sexual communication in mammals. Two populations of vomeronasal sensory neurons, each expressing G?i2 or G?o proteins, send projections to glomeruli of the rostral or caudal accessory olfactory bulb, rAOB and cAOB, respectively. In rodents, the G?i2- and G?o-expressing vomeronasal pathways have shown differential responses to small/volatile vs. large/non-volatile semiochemicals, respectively. Moreover, early gene expression suggests predominant activation of rAOB and cAOB neurons in sexual vs. aggressive contexts, respectively. We recently described the AOB of Octodon degus, a semiarid-inhabiting diurnal caviomorph. Their AOB has a cell indentation between subdomains and the rAOB is twice the size of the cAOB. Moreover, their AOB receives innervation from the lateral aspect, contrasting with the medial innervation of all other mammals examined to date. Aiming to relate AOB anatomy with lifestyle, we performed a morphometric study on the AOB of the capybara, a semiaquatic caviomorph whose lifestyle differs remarkably from that of O. degus. Capybaras mate in water and scent-mark their surroundings with oily deposits, mostly for male–male communication. We found that, similar to O. degus, the AOB of capybaras shows a lateral innervation of the vomeronasal nerve, a cell indentation between subdomains and heterogeneous subdomains, but in contrast to O. degus the caudal portion is larger than the rostral one. We also observed that four other caviomorph species present a lateral AOB innervation and a cell indentation between AOB subdomains, suggesting that those traits could represent apomorphies of the group. We propose that although some AOB traits may be phylogenetically conserved in caviomorphs, ecological specializations may play an important role in shaping the AOB.

Suarez, Rodrigo; Santibanez, Rodrigo; Parra, Daniela; Coppi, Antonio A; Abrahao, Luciana M B; Sasahara, Tais H C; Mpodozis, Jorge

2011-01-01

21

Using Differentials to Differentiate Trigonometric and Exponential Functions  

ERIC Educational Resources Information Center

|Starting from geometric definitions, we show how differentials can be used to differentiate trigonometric and exponential functions without limits, numerical estimates, solutions of differential equations, or integration.|

Dray, Tevian

2013-01-01

22

Double accessory tongue  

Microsoft Academic Search

The authors report a case of double accessory tongue in a female neonate. The embryology of this extremely rare congenital anomaly, along with the diagnostic approach followed and the surgical intervention undertaken, are discussed. The surgical procedure was radical and led to good functional and esthetic results.

F. S. Chiarenza; A. D'Alessio; S. De Pascale; M. Cheli; C. Giardina; G. Rota; D. Schievano; G. Locatelli

1994-01-01

23

Accessory ossicles and sesamoid bones of the ankle and foot: imaging findings, clinical significance and differential diagnosis  

Microsoft Academic Search

Accessory ossicles and sesamoid bones are frequent findings in routine radiographs of the ankle and foot. They are commonly considered fortuitous and unrelated to the patient's complaint; however, they may eventually cause painful syndromes or degenerative changes in response to overuse and trauma. They may also suffer or simulate fractures. Our aim was to review, illustrate and discuss the imaging

J. M. Mellado; A. Ramos; E. Salvadó; A. Camins; M. Danús; A. Saurí

2003-01-01

24

Dietary n-3 PUFA affect TcR-mediated activation of purified murine T cells and accessory cell function in co-cultures  

PubMed Central

Diets enriched in n-3 polyunsaturated fatty acids (PUFA) suppress several functions of murine splenic T cells by acting directly on the T cells and/or indirectly on accessory cells. In this study, the relative contribution of highly purified populations of the two cell types to the dietary suppression of T cell function was examined. Mice were fed diets containing different levels of n-3 PUFA; safflower oil (SAF; control containing no n-3 PUFA), fish oil (FO) at 2% and 4%, or 1% purified docosahexaenoic acid (DHA) for 2 weeks. Purified (>90%) T cells were obtained from the spleen, and accessory cells (>95% adherent, esterase-positive) were obtained by peritoneal lavage. Purified T cells or accessory cells from each diet group were co-cultured with the alternative cell type from every other diet group, yielding a total of 16 different co-culture combinations. The T cells were stimulated with either concanavalin A (ConA) or antibodies to the T cell receptor (TcR)/CD3 complex and the costimulatory molecule CD28 (?CD3/?CD28), and proliferation was measured after four days. Suppression of T cell proliferation in the co-cultures was dependent upon the dose of dietary n-3 PUFA fed to mice from which the T cells were derived, irrespective of the dietary treatment of accessory cell donors. The greatest dietary effect was seen in mice consuming the DHA diet (P = 0·034 in the anova; P = 0·0053 in the Trend Test), and was observed with direct stimulation of the T cell receptor and CD28 costimulatory ligand, but not with ConA. A significant dietary effect was also contributed accessory cells (P = 0·033 in the Trend Test). We conclude that dietary n-3 PUFA affect TcR-mediated by T cell activation by both direct and indirect (accessory cell) mechanisms.

CHAPKIN, R S; ARRINGTON, J L; APANASOVICH, T V; CARROLL, R J; MCMURRAY, D N

2002-01-01

25

Functional Differentiation of Computer Programs  

Microsoft Academic Search

We present a purely functional implementation of the computational differentiation tools—the well known numeric (i.e., not symbolic) techniques which permit one to compute point-wise derivatives of functions defined by computer programs economically and exactly (with machine precision). We show how the use of lazy evaluation permits a transparent and elegant construction of the entire infinite tower of derivatives of higher

Jerzy Karczmarczuk

2001-01-01

26

Functions of replication factor C and proliferating-cell nuclear antigen: Functional similarity of DNA polymerase accessory proteins from human cells and bacteriophage T4  

SciTech Connect

The proliferating-cell nuclear antigen (PCNA) and the replication factors A and C (RF-A and RF-C) are cellular proteins essential for complete elongation of DNA during synthesis from the simian virus 40 origin of DNA replication in vitro. All three cooperate to stimulate processive DNA synthesis by DNA polymerase {delta} on a primed single-stranded M13 template DNA and as such can be categorized as DNA polymerase accessory proteins. Biochemical analyses with highly purified RF-C and PCNA have demonstrated functions that are completely analogous to the functions of bacteriophage T4 DNA polymerase accessory proteins. A primer-template-specific DNA binding activity and a DNA-dependent ATPase activity copurified with the multisubunit protein RF-C and are similar to the functions of the phage T4 gene 44/62 protein complex. Furthermore, PCNA stimulated the RF-C ATPase activity and is, therefore, analogous to the phage T4 gene 45 protein, which stimulates the ATPase function of the gene 44/62 protein complex. Indeed, some primary sequence similarities between human PCNA and the phage T4 gene 45 protein could be detected. These results demonstrate a striking conservation of the DNA replication apparatus in human cells and bacteriophage T4.

Tsurimoto, Toshiki; Stillman, B. (Cold Spring Harbor Laboratory, NY (USA))

1990-02-01

27

Functions of replication factor C and proliferating-cell nuclear antigen: functional similarity of DNA polymerase accessory proteins from human cells and bacteriophage T4.  

PubMed Central

The proliferating-cell nuclear antigen (PCNA) and the replication factors A and C (RF-A and RF-C) are cellular proteins essential for complete elongation of DNA during synthesis from the simian virus 40 origin of DNA replication in vitro. All three cooperate to stimulate processive DNA synthesis by DNA polymerase delta on a primed single-stranded M13 template DNA and as such can be categorized as DNA polymerase accessory proteins. Biochemical analyses with highly purified RF-C and PCNA have demonstrated functions that are completely analogous to the functions of bacteriophage T4 DNA polymerase accessory proteins. A primer-template-specific DNA binding activity and a DNA-dependent ATPase activity copurified with the multisubunit protein RF-C and are similar to the functions of the phage T4 gene 44/62 protein complex. Furthermore, PCNA stimulated the RF-C ATPase activity and is, therefore, analogous to the phage T4 gene 45 protein, which stimulates the ATPase function of the gene 44/62 protein complex. Indeed, some primary sequence similarities between human PCNA and the phage T4 gene 45 protein could be detected. These results demonstrate a striking conservation of the DNA replication apparatus in human cells and bacteriophage T4. Images

Tsurimoto, T; Stillman, B

1990-01-01

28

Functional Differentiation in EVS modeling  

NASA Astrophysics Data System (ADS)

Ensembles with Variable Structures (EVS) were introduced in mid-1990s as stochastic milti-agent models in which agents possessed either formal diversity (described in a multi-dimensional vector space of abstract characteristics) or resource-oriented diversity (Trofimova, 2000). The process of functional differentiation (i.e. appearance of functional roles) is modelled as constraints on the flow of resources which pass through agents of the model. These constraints are: 1) the maximum amount of resource that an individual can accept from outside, 2) the maximum amount of resource that an individual can give back to the population or other environment, 3) distribution of the exchange of the resource over time (frequency and amount of the resource per step), and 4) the maximum amount of contacts that an individual can hold with such environment (sociability). Sociability appears to have a major impact on clustering dynamics within the population and to be an order parameter in phase transition in clustering behaviour, therefore it interfered with functional differentiation. Two patterns of functional differentiation were observed, before and after the phase transition in clustering, corresponding to sociability values below and after the critical points.

Trofimova, Irina; Sulis, William

2011-03-01

29

Surgical and conservative methods for restoring impaired motor function - facial nerve, spinal accessory nerve, hypoglossal nerve (not including vagal nerve or swallowing)  

PubMed Central

The present review gives a survey of rehabilitative measures for disorders of the motor function of the mimetic muscles (facial nerve), and muscles innervated by the spinal accessory and hypoglossal nerves. The dysfunction can present either as paralysis or hyperkinesis (hyperkinesia). Conservative and surgical treatment options aimed at restoring normal motor function and correcting the movement disorders are described. Static reanimation techniques are not dealt with. The final section describes the use of botulinum toxin in the therapy of dysphagia.

Laskawi, R.; Rohrbach, S.

2005-01-01

30

A novel ML protein from Manduca sexta may function as a key accessory protein for lipopolysaccharide signaling.  

PubMed

Lipopolysaccharide (LPS) present on the outer membrane of Gram-negative bacteria is one of the most important pathogen-associated molecular patterns and a potent elicitor in innate immunity. In human, TLR4 (Toll-like receptor 4) and MD-2 (myeloid differiation-2) form a receptor complex to transduce the LPS signal into cells. However, in invertebrates, receptors that recognize LPS have not been determined. Here we report the purification, characterization and cDNA cloning of an ML (MD-2-related lipid-recognition) protein from the tobacco hornworm Manduca sexta. The full-length cDNA of this M. sexta ML protein, named MsML-1, is 532bp with an open reading frame of 456bp that encodes a polypeptide of 151 amino acids containing an ML domain. MsML-1 is a secreted glycoprotein and its mRNA is expressed in fat body and hemocytes. The expression level of MsML-1 mRNA in fat body and hemocytes as well as MsML-1 protein in hemolymph are not induced by immune challenge. Recombinant MsML-1 protein specifically binds to LPS from several Gram-negative bacteria and LPS Re mutant, as well as to lipid A, but not to KDO (2-keto-3-deoxyoctonate). Our results suggest that MsML-1 may function as a key accessory protein for LPS signaling in M. sexta against Gram-negative bacterial infection. PMID:18343500

Ao, Jing-qun; Ling, Erjun; Rao, Xiang-jun; Yu, Xiao-Qiang

2008-03-17

31

The Accessory Genome of Pseudomonas aeruginosa  

PubMed Central

Summary: Pseudomonas aeruginosa strains exhibit significant variability in pathogenicity and ecological flexibility. Such interstrain differences reflect the dynamic nature of the P. aeruginosa genome, which is composed of a relatively invariable “core genome” and a highly variable “accessory genome.” Here we review the major classes of genetic elements comprising the P. aeruginosa accessory genome and highlight emerging themes in the acquisition and functional importance of these elements. Although the precise phenotypes endowed by the majority of the P. aeruginosa accessory genome have yet to be determined, rapid progress is being made, and a clearer understanding of the role of the P. aeruginosa accessory genome in ecology and infection is emerging.

Kung, Vanderlene L.; Ozer, Egon A.; Hauser, Alan R.

2010-01-01

32

Aspergillus terreus accessory conidia are multinucleated, hyperpolarizing structures that display differential dectin staining and can induce heightened inflammatory responses in a pulmonary model of aspergillosis  

PubMed Central

In addition to phialidic conidia (PC), A. terreus produces accessory conidia (AC) both in vitro and in vivo. AC are distinct from PC in cell surface architecture, with the AC surfaces displaying more ?-glucan, a molecule that can be a trigger for the induction of inflammatory responses. The present study follows ?-glucan cell surface presentation throughout the course of germination of both types of conidia, and analyzes the differential capacity of AC and PC to elicit immune responses. Results show that AC display early, increased dectin-1 labeling on their cell surfaces compared to PC, and this differential dectin-1 labeling is sustained on the cell surface from the time of breaking dormancy through early germ tube emergence. Mouse alveolar macrophages showed a stronger inflammatory cytokine/chemokine response when challenged with AC than with PC in both ex vivo and in vivo experiments, correlating with the greater exposure of ?-glucan exhibited by AC. Further, histopathologic staining of the lungs from mice challenged with AC demonstrated heightened cell recruitment and increased inflammatory response compared to the lungs of mice challenged with PC. Our study also demonstrates that AC are multinucleate structures with the ability to germinate rapidly, polarizing in multiple directions and producing several hyphal extensions. We present evidence that A. terreus AC are phenotypically distinct from PC and can be potent activators of the innate immune mechanism thus possibly playing a role in this organism's pathogenesis.

Deak, Eszter; Nelson, Michael; Hernandez-Rodriguez, Yainitza; Gade, Lalitha; Baddley, John; Momany, Michelle; Steele, Chad

2011-01-01

33

Detecting Differential Person Functioning in Emotional Intelligence  

ERIC Educational Resources Information Center

|Differential Item Functioning (DIF) is a widely used term in test development literature. It is very important to analyze test's data for DIF because It is a serious threat to validity. If the same data matrix was transposed, similar analysis can be carried for Differential Person Functioning (DPF). The purpose of this paper is to introduce and…

Alsmadi, Yahia M.; Alsmadi, Abdalla A.

2009-01-01

34

A novel function for the Hox gene Abd-B in the male accessory gland regulates the long-term female post-mating response in Drosophila.  

PubMed

In insects, products of the male reproductive tract are essential for initiating and maintaining the female post-mating response (PMR). The PMR includes changes in egg laying, receptivity to courting males, and sperm storage. In Drosophila, previous studies have determined that the main cells of the male accessory gland produce some of the products required for these processes. However, nothing was known about the contribution of the gland's other secretory cell type, the secondary cells. In the course of investigating the late functions of the homeotic gene, Abdominal-B (Abd-B), we discovered that Abd-B is specifically expressed in the secondary cells of the Drosophila male accessory gland. Using an Abd-B BAC reporter coupled with a collection of genetic deletions, we discovered an enhancer from the iab-6 regulatory domain that is responsible for Abd-B expression in these cells and that apparently works independently from the segmentally regulated chromatin domains of the bithorax complex. Removal of this enhancer results in visible morphological defects in the secondary cells. We determined that mates of iab-6 mutant males show defects in long-term egg laying and suppression of receptivity, and that products of the secondary cells are influential during sperm competition. Many of these phenotypes seem to be caused by a defect in the storage and gradual release of sex peptide in female mates of iab-6 mutant males. We also found that Abd-B expression in the secondary cells contributes to glycosylation of at least three accessory gland proteins: ovulin (Acp26Aa), CG1656, and CG1652. Our results demonstrate that long-term post-mating changes observed in mated females are not solely induced by main cell secretions, as previously believed, but that secondary cells also play an important role in male fertility by extending the female PMR. Overall, these discoveries provide new insights into how these two cell types cooperate to produce and maintain a robust female PMR. PMID:23555301

Gligorov, Dragan; Sitnik, Jessica L; Maeda, Robert K; Wolfner, Mariana F; Karch, François

2013-03-28

35

Accessory subunits of mitochondrial complex I.  

PubMed

Mitochondrial complex I has a molecular mass of almost 1 MDa and comprises more than 40 polypeptides. Fourteen central subunits harbour the bioenergetic core functions. We are only beginning to understand the significance of the numerous accessory subunits. The present review addresses the role of accessory subunits for assembly, stability and regulation of complex I and for cellular functions not directly associated with redox-linked proton translocation. PMID:24059519

Kmita, Katarzyna; Zickermann, Volker

2013-10-01

36

Extracting differential pair distribution functions using MIXSCAT  

SciTech Connect

Differently weighted experimental scattering data have been used to extract partial or differential structure factors or pair distribution functions in studying many materials. However, this is not done routinely partly because of the lack of user-friendly software. This paper presents MIXSCAT, a new member of the DISCUS program package. MIXSCAT allows one to combine neutron and X-ray pair distribution functions and extract their respective differential functions.

Wurden, Caroline; Page, Katharine; Llobet, Anna; White, Claire E.; Proffen, Thomas (LANL)

2010-08-27

37

Sinc function and generalized digital fractional differentiators  

Microsoft Academic Search

The topics on fractional-order derivative are studied from the viewpoint of signal processing. Firstly, some basic concepts and fundamental properties of fractional derivative and its operator are discussed. Secondly, the ideal digital fractional differentiator is proposed in this paper; its basic conditions and integral formula for filtering coefficients are given. And next the concept of differentiator coefficient function which is

Xiao Yuan; Yonghai Wei; Juebang Yu

2004-01-01

38

Semistability of retarded functional differential equations  

Microsoft Academic Search

In this paper, we develop a semistability analy- sis framework for retarded functional differential equations (RFDE) having a continuum of equilibria with time-varying parameters and delays with applications to stability analysis of multiagent dynamic networks with consensus protocols in the presence of unknown heterogeneous time-varying delays and parameters along the communication links. We show that for such a retarded functional

Qing Hui

2011-01-01

39

Detecting Differential Item Functioning and Differential Step Functioning due to Differences that "Should" Matter  

ERIC Educational Resources Information Center

|This study illustrates the use of differential item functioning (DIF) and differential step functioning (DSF) analyses to detect differences in item difficulty that are related to experiences of examinees, such as their teachers' instructional practices, that are relevant to the knowledge, skill, or ability the test is intended to measure. This…

Miller, Tess; Chahine, Saad; Childs, Ruth A.

2010-01-01

40

Dendritic cells are specialized accessory cells along with TGF-? for the differentiation of Foxp3+ CD4+ regulatory T cells from peripheral Foxp3? precursors  

PubMed Central

Foxp3+CD25+CD4+ regulatory T cells are produced in the thymus (natural T regs) but can also differentiate from peripheral Foxp3?CD4+ precursors (induced or adaptive T regs). We assessed antigen presenting cell (APC) requirements for the latter differentiation. With added transforming growth factor (TGF)-?, both immature and mature populations of dendritic cells (DCs) induced antigen-specific Foxp3+ T regs from Foxp3? precursors. Using endogenous TGF-?, DCs from gut-associated mesenteric lymph nodes were capable of differentiating Foxp3+T regs. Spleen DCs were 100-fold more potent than DC-depleted APCs for the induction of T regs and required 10-fold lower doses of peptide antigen. Interleukin-2 (IL-2) was essential, but could be provided endogenously by T cells stimulated by DCs, but not other APCs. The required IL-2 was induced by DCs that expressed CD80/CD86 costimulatory molecules. The DC-induced Foxp3+T regs divided up to 6 times in 6 days and were comprised of CD62L and CD103 positive and negative forms. The induced Foxp3+T regs exerted suppression in vitro and blocked tumor immunity in vivo. These results indicate that DCs are specialized to differentiate functional peripheral Foxp3+T regs and help set the stage to use DCs to actively suppress the immune response in an antigen-specific manner.

Bonito, Anthony J.; Spisek, Radek; Dhodapkar, Madhav; Inaba, Kayo; Steinman, Ralph M.

2007-01-01

41

Intrapancreatic accessory spleen.  

PubMed

A case of accessory spleen located in the tail of the pancreas in a stillbirth male foetus is reported. The congenital anomaly was revealed at autopsy. The intrapancreatic spleen was well demarcated and was composed of red and white pulp; however, same pancreatic ducts were intermingled with the splenic parenchyma. As well as the intrapancreatic lesion another minute accessory spleen was also found at the hilum of the proper organ. Since a lack of morphological features of trisomy 13 syndrome were found in the foetus, the ectopic spleens were regarded as incidental findings. PMID:22532185

Szumi?o, J; Fronczek, A; Bukharin, S; Burdan, F

2012-02-01

42

Differential Item Functioning: A Mixture Distribution Conceptualization.  

ERIC Educational Resources Information Center

|Conducted a Monte Carlo study to compare various approaches to detecting differential item functioning (DIF) under a conceptualization of DIF that recognizes that observed data are a mixture of data from multiple latent populations or classes. Demonstrated the usefulness of the approach. (SLD)|

De Ayala, Ralph J.; Kim, Seock-Ho; Stapleton, Laura M.; Dayton, C. Mitchell

2002-01-01

43

A Reconceptualization of Differential Item Functioning.  

ERIC Educational Resources Information Center

|Differential item functioning (DIF) may be defined as an item that displays different statistical properties for different groups after the groups are matched on an ability measure. For instance, with binary data, DIF exists when there is a difference in the conditional probabilities of a correct response for two manifest groups. This paper…

De Ayala, R. J.; Kim, Seock-Ho; Stapleton, Laura M.; Dayton, C. Mitchell

44

Functional Differential Inclusions with Integral Boundary Conditions  

Microsoft Academic Search

In this paper, we investigate the existence of solutions for a class of second order functional differential inclusions with integral boundary conditions. By using suitable fixed point theorems, we study the case when the right hand side has convex as well as nonconvex values.

Mouffak Benchohra; Samira Hamani; Johnny Henderson

2007-01-01

45

Differential Item Functioning Analysis Using Rasch Item Information Functions  

Microsoft Academic Search

Differential item functioning (DIF) analysis is a statistical technique used for ensuring the equity and fairness of educational assessments. This study formulates a new DIF analysis method using the information similarity index (ISI). ISI compares item information functions when data fits the Rasch model. Through simulations and an international assessment example, ISI, the signed area index (SAI), and Mantel-Haenszel procedure,

Adam E. Wyse; Raymond Mapuranga

2009-01-01

46

Accessory pathway reciprocating tachycardia.  

PubMed

Patients who have an accessory pathway (AP) of atrioventricular (AV) conduction may develop circus movement tachycardia otherwise known as atrioventricular re-entrant tachycardia (AVRT). Orthodromic AVRT is the most common form. It occurs as a result of antegrade conduction through the normal AV conduction system and retrograde conduction to the atria via the AP. Less commonly, conduction occurs in the opposite direction resulting in antidromic AVRT. Tachycardia may also involve multiple APs which may provide both antegrade and retrograde conduction and may alternate antegradely or retrogradely. Tachycardia may occur in which the AP simply acts as a bystander, and does not participate in the tachycardia mechanism. When atrial fibrillation is conducted to the ventricles via and AP, the resultant ventricular rate may be extremely rapid, placing the patient at risk of developing ventricular fibrillation and cardiac arrest. This paper reviews the anatomical and physiological substrates involved in the pathogenesis of AVRT. The acute and long-term management of patients who suffer from these arrhythmias will then be discussed. The normal AV annulus is composed exclusively of electrically inert fibrous tissue. The AV node and His bundle normally act as the sole route of electrical conduction. Accessory pathways occur at all points along the AV ring, and usually occur as isolated abnormalities, although a proportion of patients have associated congenital abnormalities. This is particularly true of right-sided APs. Most APs exhibit non-decremental conduction properties, and conduct faster than normal AV conduction tissue. In many patients with APs the surface ECG reveals clear evidence of pre-excitation, and a good idea of pathway localization is possible using one or more of several algorithms which have been developed. Patients with latent pre-excitation, intermittent pre-excitation, and patients with concealed APs have not evidence of pre-excitation on a proportion or all of Their surface ECGs. Patients present with a history of paroxysmal palpitations, often with associated symptoms such as chest discomfort Syncope is a rare presenting symptom. Unless bundle branch block is present, patients with orthodromic AVRT exhibit a narrow complex tachycardia on the surface ECG. Patients with pre-excited tachycardia including antidromic AVRT, and other forms of SVT in which the AP conducts to the ventricles as a bystander but does not participate in the tachycardias mechanism, present as broad complex tachycardias on the surface ECG which may be difficult to distinguish from ventricular tachycardia. Adenosine is increasingly used for this purpose since it is highly efficacious and has an extremely short half-life. Adenosine is also very useful in the diagnosis of broad-complex tachycardia, and in unmasking latent pre-excitation during sinus rhythm. Electrophysiology study in these patients is frequently performed at the same time as an attempt at catheter ablation; it aims to diagnose, localize and determine the functional characteristics of an AP, and to characterize the role of the pathway in tachycardia. AVRT can be reliably terminated by effective AV nodal blockade. Drug therapy for the prevention of AVRT is useful for temporary control whilst awaiting more definitive measures and in certain cases as long-term management. No class of drug stands out as 'therapy of choice', and physician preference, pro-arrhythmic effects and associated conditions need to be taken into account such that an individual choice can be made in each patient. The management of patients with AVRT has been revolutionized in recent years with the advent of catheter-based techniques for their cure. Whilst this method of treatment is highly effective and has low complication rates, pathways in particular locations such as the septal region remain challenging. PMID:9717020

Obel, O A; Camm, A J

1998-05-01

47

Metabolic regulation of osteoclast differentiation and function.  

PubMed

The osteoclast is a giant cell that resorbs calcified matrix by secreting acids and collagenolytic enzymes. The molecular mechanisms underlying metabolic adaptation to the increased biomass and energetic demands of osteoclastic bone resorption remain elusive. Here we show that during osteoclastogenesis the expression of both glucose transporter 1 (Glut1) and glycolytic genes is increased, whereas the knockdown of hypoxia-inducible factor 1-alpha (Hif1?), as well as glucose deprivation, inhibits the bone-resorbing function of osteoclasts, along with a suppression of Glut1 and glycolytic gene expression. Furthermore, the expression of the glutamine transporter solute carrier family 1 (neutral amino acid transporter), member 5 (Slc1a5) and glutaminase 1 was increased early in differentiation, and a depletion of L-glutamine or pharmacological inhibition of the Slc1a5 transporter suppressed osteoclast differentiation and function. Inhibition of c-Myc function abrogated osteoclast differentiation and function, along with a suppression of Slc1a5 and glutaminase 1 gene expression. Genetic and pharmacological inhibition of mammalian target of rapamycin (mTOR), as well as the activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK), inhibited osteoclastogenesis. Thus, the uptake of glucose and glutamine and utilization of the carbon sources derived from them, coordinated by HIF1? and c-Myc, are essential for osteoclast development and bone-resorbing activity through a balanced regulation of the nutrient and energy sensors, mTOR and AMPK. © 2013 American Society for Bone and Mineral Research. PMID:23661628

Indo, Yoriko; Takeshita, Sunao; Ishii, Kiyo-Aki; Hoshii, Takayuki; Aburatani, Hiroyuki; Hirao, Atsushi; Ikeda, Kyoji

2013-11-01

48

Unusual insidious spinal accessory nerve palsy: a case report  

Microsoft Academic Search

INTRODUCTION: Isolated spinal accessory nerve dysfunction has a major detrimental impact on the functional performance of the shoulder girdle, and is a well-documented complication of surgical procedures in the posterior triangle of the neck. To the best of our knowledge, the natural course and the most effective way of handling spontaneous spinal accessory nerve palsy has been described in only

Ioannis N Charopoulos; Nikolas Hadjinicolaou; Ioannis Aktselis; George P Lyritis; Nikolaos Papaioannou; Constantinos Kokoroghiannis

2010-01-01

49

Differential Item Functioning Depending on General Covariates  

Microsoft Academic Search

\\u000a Item response theory (IRT) is a powerful tool for the detection of differential item functioning (DIF). It is shown that the\\u000a class of IRT models with manifest predictors is a comprehensive framework for the detection of DIF. These models also support\\u000a the investigation of the causes of DIF. In principle, the responses to every item in a test can be

Cees A. W. Glas

50

Differential item functioning and health assessment  

Microsoft Academic Search

Establishing measurement equivalence is important because inaccurate assessment may lead to incorrect estimates of effects\\u000a in research, and to suboptimal decisions at the individual, clinical level. Examination of differential item functioning (DIF)\\u000a is a method for studying measurement equivalence. An item (i.e., one question in a longer scale) exhibits DIF if the item\\u000a response differs across groups (e.g., gender, race),

Jeanne A. Teresi; John A. Fleishman

2007-01-01

51

Differentiability of Lieb functional in electronic density functional theory  

NASA Astrophysics Data System (ADS)

A solid understanding of the Lieb functional FL is important because of its centrality in the foundations of electronic density functional theory. A basic question is whether directional derivatives of FL at an ensemble-V-representable density are given by (minus) the potential. A widely accepted purported proof that FL is Gâteaux differentiable at EV-representable densities would say, ?yes.? But that proof is fallacious, as shown here. FL is not Gâteaux differentiable in the normal sense, nor is it continuous. By means of a constructive approach, however, we are able to show that the derivative of FL at an EV-representable density ?0 in the direction of ?1 is given by the potential if ?0 and ?1 are everywhere strictly greater than zero, and they and the ground state wave function have square integrable derivatives through second order.

Lammert, Paul E.

52

Evidence that the potyvirus P1 proteinase functions in trans as an accessory factor for genome amplification.  

PubMed Central

The tobacco etch potyvirus (TEV) polyprotein is proteolytically processed by three viral proteinases (NIa, HC-Pro, and P1). While the NIa and HC-Pro proteinases each provide multiple functions essential for viral infectivity, the role of the P1 proteinase beyond its autoproteolytic activity is understood poorly. To determine if P1 is necessary for genome amplification and/or virus movement from cell to cell, a mutant lacking the entire P1 coding region (delta P1 mutant) was produced with a modified TEV strain (TEV-GUS) expressing beta-glucuronidase (GUS) as a reporter, and its replication and movement phenotypes were assayed in tobacco protoplasts and plants. The delta P1 mutant accumulated in protoplasts to approximately 2 to 3% the level of parental TEV-GUS, indicating that the P1 protein may contribute to but is not strictly required for viral RNA amplification. The delta P1 mutant was capable of cell-to-cell and systemic (leaf-to-leaf) movement in plants but at reduced rates compared with parental virus. This is in contrast to the S256A mutant, which encodes a processing-defective P1 proteinase and which was nonviable in plants. Both delta P1 and S256A mutants were complemented by P1 proteinase expressed in a transgenic host. In transgenic protoplasts, genome amplification of the delta P1 mutant relative to parental virus was stimulated five- to sixfold. In transgenic plants, the level of accumulation of the delta P1 mutant was stimulated, although the rate of cell-to-cell movement was the same as in nontransgenic plants. Also, the S256A mutant was capable of replication and systemic infection in P1-expressing transgenic plants. These data suggest that, in addition to providing essential processing activity, the P1 proteinase functions in trans to stimulate genome amplification.

Verchot, J; Carrington, J C

1995-01-01

53

Aircraft-Engine-Accessory Vibration  

Microsoft Academic Search

1. The overhang-moment limit, or still better a limit on the moment of inertia of the accessory about a line through the center of the accessory mounting surface, would be helpful by limiting one of the two factors which control the natural frequency of the accessory-rear-cover combination. However, the natural frequency is the factor of prime importance, and, if control

John Tyler

1944-01-01

54

Differential item functioning and health assessment.  

PubMed

Establishing measurement equivalence is important because inaccurate assessment may lead to incorrect estimates of effects in research, and to suboptimal decisions at the individual, clinical level. Examination of differential item functioning (DIF) is a method for studying measurement equivalence. An item (i.e., one question in a longer scale) exhibits DIF if the item response differs across groups (e.g., gender, race), controlling for an estimate of the construct being measured. A distinction between applications in health, as contrasted with other settings such as educational and aptitude testing, is that there are many health-related constructs and multiple measures of each, few of which have received much critical evaluation. Discussed in this article are several methods for detection of differential item functioning (DIF), including non-parametric and parametric methods such as logistic regression, and those based on item response theory. Basic definitions and criteria for DIF detection are provided, as are steps in performing the analyses. Recommendations are presented and future directions discussed. PMID:17443420

Teresi, Jeanne A; Fleishman, John A

2007-04-19

55

Accessory apartment conversion programs.  

PubMed

In recent years, state housing finance agencies have joined with state units on aging to develop programs to help the frail, elderly homeowner. Under an accessory apartment conversion program, a low-income homeowner will borrow money at a reduced interest rate to underwrite conversion of excess space into a rental apartment. The tenant will provide additional income as well as, ideally, certain kinds of personal assistance and a friendly presence. To date, few elderly clients have used this option. The initial rationale for the program is explained as are plausible reasons for the fact that it has not met expectations. PMID:10186784

Retsinas, J; Retsinas, N P

1991-01-01

56

Distinguishing Differential Testlet Functioning from Differential Bundle Functioning Using the Multilevel Measurement Model  

ERIC Educational Resources Information Center

This study extends the multilevel measurement model to handle testlet-based dependencies. A flexible two-level testlet response model (the MMMT-2 model) for dichotomous items is introduced that permits assessment of differential testlet functioning (DTLF). A distinction is made between this study's conceptualization of DTLF and that of…

Beretvas, S. Natasha; Walker, Cindy M.

2012-01-01

57

Giant Accessory Right-Sided Suprarenal Spleen in Thalassaemia  

PubMed Central

An accessory spleen is defined as ectopic splenic tissue that develops due to failure of fusion of cells during embryonic development as they migrate from the midline to the left upper quadrant. While benign, complications may arise which include trauma, torsion, or infarction of the ectopic tissue. Additionally, patients who have had a splenectomy secondary to treatment for previous pathology such as a haematological malignancy or idiopathic thrombocytopenia purpura may experience persistent symptoms due to the accessory splenic tissue. The presence of an accessory spleen is therefore of significant diagnostic and therapeutic importance. To the best of the authors' knowledge, this case is the second and largest reported case of a giant right suprarenal accessory spleen and highlights the difficulty in differentiation of these masses from malignant adrenal tumours.

Arra, A.; Ramdass, Michael J.; Mohammed, A.; Okoye, O.; Thomas, D.; Barrow, S.

2013-01-01

58

Accessory antlers in male Cervidae  

Microsoft Academic Search

Accessory (supernumerary) antlers are an infrequent phenomenon in male cervids. These bony protuberances grow mostly from permanent pedicles, which developed in response to a repeated or a severe trauma to frontal, nasal or parietal bones. They regularly undergo seasonal mineralization, casting and regrowth and may persist for many years. Three examples of accessory antlers in telemetacarpal cervids, roe deer (Capreolus

G. A. Bubenik; K. J. Hundertmark

2002-01-01

59

Thermomechanical milling of accessory lithics in volcanic conduits  

NASA Astrophysics Data System (ADS)

Accessory lithic clasts recovered from pyroclastic deposits commonly result from the failure of conduit wall rocks, and represent an underutilized resource for constraining conduit processes during explosive volcanic eruptions. The morphological features of lithic clasts provide distinctive 'textural fingerprints' of processes that have reshaped them during transport in the conduit. Here, we present the first study focused on accessory lithic clast morphology and show how the shapes and surfaces of these accessory pyroclasts can inform on conduit processes. We use two main types of accessory lithic clasts from pyroclastic fallout deposits of the 2360 B.P. subplinian eruption of Mount Meager, British Columbia, as a case study: (i) rough and subangular dacite clasts, and (ii) variably rounded and smoothed monzogranite clasts. The quantitative morphological data collected on these lithics include: mass, volume, density, 2-D image analysis of convexity (C), and 3-D laser scans for sphericity (?) and smoothness (S). Shaping and comminution (i.e. milling) of clasts within the conduit are ascribed to three processes: (1) disruptive fragmentation due to high-energy impacts between clasts or between clasts and conduit walls, (2) ash-blasting of clasts suspended within the volcanic flux, and (3) thermal effects. We use a simplified conduit eruption model to predict ash-blasting velocities and lithic residence times as a function of clast size and source depth, thereby constraining the lithic milling processes. The extent of shape and surface modification (i.e. rounding and honing) is directly proportional to clast residence times within the conduit prior to evacuation. We postulate that the shallow-seated dacite clasts remain subangular and rough due to short (<2 min) residence times, whereas monzogranite clasts are much more rounded and smoothed due to deeper source depths and consequently longer residence times (up to ˜1 h). Larger monzogranite clasts are smoother than smaller clasts due to longer residence times and to greater differential velocities within the ash-laden jet. Lastly, our model residence times and mass loss estimates for rounded clasts are used to estimate minimum attrition rates due to volcanic ash-blasting within the conduit (e.g., 12 cm3?s?1 for 25 cm clasts, sourced at 2500 m depth).

Campbell, Michelle E.; Russell, James K.; Porritt, Lucy A.

2013-09-01

60

Subclasses of vomeronasal receptor neurons: differential expression of G proteins (G i?2 and G o?) and segregated projections to the accessory olfactory bulb  

Microsoft Academic Search

Differential expression of G proteins (Gi?2 and Go?) and the separate central projections of Gi?2- and Go?-immunoreactive (ir) vomeronasal receptor neurons were investigated in the mouse and rat using immunocytochemical methods. In the vomeronasal organ (VNO), receptor neurons with their cell bodies located in the middle layer (middle 1\\/3) of the vomeronasal sensory epithelium express Gi?2. Axons of these Gi?2-ir

Changping Jia; Mimi Halpern

1996-01-01

61

Asymptotic Attractivity Results For Functional Differential Equation In Banach Algebras  

NASA Astrophysics Data System (ADS)

In this paper, we have proved an existence results for local asymptotic attractivity and existence of asymptotic stability of solutions for nonlinear functional differential equations in Banach algebras.

Salunkhe, S. N.

2012-09-01

62

Adenosine receptors in regulation of dendritic cell differentiation and function  

Microsoft Academic Search

Differentiation of functional dendritic cells (DCs) critically depends on the microenvi- ronment. DCs differentiate in hypoxic tu- mor sites and inflamed or damaged tis- sue. Because local concentrations of adenosine reach high physiologically rel- evant levels in these conditions, we as- sessed the expression of adenosine re- ceptors and the effect of their activation on differentiation of human monocytes and

Sergey V. Novitskiy; Sergey Ryzhov; Rinat Zaynagetdinov; Anna E. Goldstein; Yuhui Huang; Oleg Y. Tikhomirov; Michael R. Blackburn; Italo Biaggioni; David P. Carbone; Igor Feoktistov; Mikhail M. Dikov

2008-01-01

63

Mechanical Accessories for Mobile Teleoperators.  

National Technical Information Service (NTIS)

The choice of optimum mechanical accessories for mobile teleoperators involves matching the criteria for emergency response with the available technology. This paper presents a general background to teleoperations, a potpourri of the manipulator systems a...

M. J. Feldman J. N. Herndon

1985-01-01

64

Accessory drive for a turbine engine  

SciTech Connect

This patent describes, in combination: a radial flow turbine engine having a main shaft and a casing with air inlets open radially at one end, and an accessory drive comprising: an accessory housing positioned axially adjacent the one end of the turbine engine casing, a gear ring rotatably mounted within the accessory housing, means for mechanically drivingly connecting the gear ring to the turbine main shaft, the connecting means comprising a planetary gear arrangement contained in the accessory housing, the accessory housing having apertures open to the gear ring and circumferentially spaced from each other, at least one accessory having a driven gear, and means for mounting the at least one accessory to the accessory housing so that the accessory registers with one of the plurality of apertures and so that the gear ring meshes with the driven gear, wherein each aperture is adapted for connection with a separate accessory.

Brogdon, J.W.; Allen, K.D.; Barton, J.S.; Hicks, R.J.

1987-02-03

65

The zebrafish prospero homolog prox1 is required for mechanosensory hair cell differentiation and functionality in the lateral line  

PubMed Central

Background The lateral line system in zebrafish is composed of a series of organs called neuromasts, which are distributed over the body surface. Neuromasts contain clusters of hair cells, surrounded by accessory cells. Results In this report we describe zebrafish prox1 mRNA expression in the migrating primordium and in the neuromasts of the posterior lateral line. Furthermore, using an antibody against Prox1 we characterize expression of the protein in different cell types within neuromasts, and we show distribution among the supporting cells and hair cells. Conclusion Functional analysis using antisense morpholinos indicates that prox1 activity is crucial for the hair cells to differentiate properly and acquire functionality, while having no role in development of other cell types in neuromasts.

2009-01-01

66

HIV-1 Accessory Proteins: Vpu and Vif.  

PubMed

HIV-1 Vif and Vpu are accessory factors involved in late stages of viral replication. Vif regulates viral infectivity by preventing virion incorporation of APOBEC3G and other members of the family of cytidine deaminases, while Vpu causes degradation of CD4 and promotes virus release by functionally inactivating the host factor BST-2. This chapter described techniques used for the characterization of Vif and Vpu and their functional interaction with host factors. Many of the techniques are, however, applicable to the functional analysis of other viral proteins. PMID:24158820

Andrew, Amy; Strebel, Klaus

2014-01-01

67

DIF Trees: Using Classification Trees to Detect Differential Item Functioning  

ERIC Educational Resources Information Center

|A nonparametric tree classification procedure is used to detect differential item functioning for items that are dichotomously scored. Classification trees are shown to be an alternative procedure to detect differential item functioning other than the use of traditional Mantel-Haenszel and logistic regression analysis. A nonparametric…

Vaughn, Brandon K.; Wang, Qiu

2010-01-01

68

Existence and uniqueness of solutions to uncertain functional differential equations  

Microsoft Academic Search

The canonical process is a Lipschitz continuous uncertain process with stationary and independent increments, and uncertain functional differential equations driven by the canonical process give a mathematical formulation for dynamic systems. This paper proves an existence and uniqueness theorem of solutions for uncertain functional differential equations under the uniform Lipschitz condition and the linear growth condition.

Hongjian Liu; Weiyin Fei

2012-01-01

69

Modular differential equations for torus one-point functions  

Microsoft Academic Search

It is shown that in a rational conformal field theory every torus one-point function of a given highest weight state satisfies a modular differential equation. We derive and solve these differential equations explicitly for some Virasoro minimal models. In general, however, the resulting amplitudes do not seem to be expressible in terms of standard transcendental functions.

Matthias R. Gaberdiel; Samuel Lang

2009-01-01

70

Controllability of fractional neutral stochastic functional differential systems  

NASA Astrophysics Data System (ADS)

In this paper, we study a class of fractional neutral stochastic functional differential systems. We obtain the controllability of the stochastic functional differential systems by the Sadovskii's fixed point theorem under some suitable assumptions. An example is given to illustrate the theory.

Kexue, Li; Jigen, Peng

2013-10-01

71

Melanocortin receptor accessory proteins in adrenal gland physiology and beyond.  

PubMed

The melanocortin receptor (MCR) family consists of five G-protein-coupled receptors (MC1R-MC5R) with diverse physiological roles. MC1R controls pigmentation, MC2R is a critical component of the hypothalamic-pituitary-adrenal axis, MC3R and MC4R have a vital role in energy homeostasis and MC5R is involved in exocrine function. The melanocortin receptor accessory protein (MRAP) and its paralogue MRAP2 are small single-pass transmembrane proteins that have been shown to regulate MCR expression and function. In the adrenal gland, MRAP is an essential accessory factor for the functional expression of the MC2R/ACTH receptor. The importance of MRAP in adrenal gland physiology is demonstrated by the clinical condition familial glucocorticoid deficiency, where inactivating MRAP mutations account for ?20% of cases. MRAP is highly expressed in both the zona fasciculata and the undifferentiated zone. Expression in the undifferentiated zone suggests that MRAP could also be important in adrenal cell differentiation and/or maintenance. In contrast, the role of adrenal MRAP2, which is highly expressed in the foetal gland, is unclear. The expression of MRAPs outside the adrenal gland is suggestive of a wider physiological purpose, beyond MC2R-mediated adrenal steroidogenesis. In vitro, MRAPs have been shown to reduce surface expression and signalling of all the other MCRs (MC1,3,4,5R). MRAP2 is predominantly expressed in the hypothalamus, a site that also expresses a high level of MC3R and MC4R. This raises the intriguing possibility of a CNS role for the MRAPs. PMID:23418361

Novoselova, T V; Jackson, D; Campbell, D C; Clark, A J L; Chan, L F

2013-03-19

72

Crystallization of accessory phases in magmas by local saturation adjacent to phenocrysts  

USGS Publications Warehouse

Accessory minerals commonly occur attached to or included in the major crystalline phases of felsic and some intermediate igneous rocks. Apatite is particularly common as inclusions, but Fe-Ti oxides, pyrrhotite, zircon, monazite, chevkinite and xenotime are also known from silicic rocks. Accessories may nucleate near the host crystal/ liquid interface as a result of local saturation owing to formation of a differentiated chemical boundary layer in which accessory mineral solubility would be lower than in the surrounding liquid. Differentiation of this boundary layer would be greatest adjacent to ferromagnesian phenocrysts, especially Fe-Ti oxides; it is with oxides that accessories are most commonly associated in rocks. A boundary layer may develop if the crystal grows more rapidly than diffusion can transport incorporated and rejected elements to and from the phenocryst. Diffusion must dominate over convection as a mode of mass transfer near the advancing crystal/liquid interface in order for a boundary layer to exist. Accumulation of essential structural constituent elements of accessory minerals owing to their slow diffusion in evolved silicate melt also may force local saturation, but this is not a process that applies to all cases. Local saturation is an attractive mechanism for enhancing fractionation during crystallization differentiation. If accessory minerals attached to or included in phenocrysts formed because of local saturation, their host phenocrysts must have grown rapidly when accessories nucleated in comparison to lifetimes of magma reservoirs. Some inconsistencies remain in a local saturation origin for accessory phases that cannot be evaluated without additional information. ?? 1989.

Bacon, C. R.

1989-01-01

73

Generalizations of the differentiability of fuzzy-number-valued functions with applications to fuzzy differential equations  

Microsoft Academic Search

The usual concept of differentiability of fuzzy-number-valued functions, has the following shortcoming: if c is a fuzzy number and g:[a,b]?R is an usual real-valued function differentiable on x0?(a,b) with g?(x0)?0, then f(x)=c?g(x) is not differentiable on x0. In this paper we introduce and study generalized concepts of differentiability (of any order n?N), which solves this shortcoming. Newton–Leibnitz-type formula is obtained

Barnabás Bede; Sorin G. Gal

2005-01-01

74

Successive approximations of solutions to stochastic functional differential equations  

Microsoft Academic Search

In the present paper, by means of the successive approximations method, the local or global existence and uniqueness theorems for a stochastic functional differential equation of the Ito type are proved.

Jan Turo

1995-01-01

75

Solving partial differential equations by collocation using radial basis functions  

Microsoft Academic Search

After a series of application papers have proven the approach to be numerically effective, this paper gives the first theoretical foundation for methods solving partial differential equations by collocation with (possibly radial) basis functions.

C. Franke; R. Schaback

1998-01-01

76

Lecture on Functional Differential Equations Vorlesung ueber Funktionaldifferential-Gleichungen.  

National Technical Information Service (NTIS)

Retarded functional differential equations were treated. The problem is formulated and solved by means of stepwise integration. The existence theorem and the univocality of the solution are discussed. The continuation of the solution forward and backward,...

E. Fuchs

1982-01-01

77

Evaluation of Accessory Materials for Desalination Plants.  

National Technical Information Service (NTIS)

Test results on accessory coatings, sealants, and polymeric products are presented. This was one part of a five-part investigation to evaluate concrete and accessory materials under a variety of temperature-pressure-salinity conditions encountered in a se...

B. V. Jones V. L. Kuehn W. R. Morrison

1973-01-01

78

21 CFR 864.3600 - Microscopes and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Microscopes and accessories. 864.3600 Section...Instrumentation and Accessories § 864.3600 Microscopes and accessories. (a) Identification. Microscopes and accessories are optical...

2010-04-01

79

21 CFR 864.3600 - Microscopes and accessories.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Microscopes and accessories. 864.3600 Section...Instrumentation and Accessories § 864.3600 Microscopes and accessories. (a) Identification. Microscopes and accessories are optical...

2009-04-01

80

Teaching Techniques for Accessory Percussion  

ERIC Educational Resources Information Center

|Everyone is familiar with the main percussion instruments of the contemporary orchestra: bass drum, snare drum, suspended cymbal, vibraphone, and timpani. But as source material broadens, so do the demands placed on the percussion section. Accessory, or auxiliary percussion, can make the difference between a typical rendition of a well-known…

Micallef, Ken

2007-01-01

81

Using Radial Basis Functions to Approximate Battery Differential Capacity and Differential Voltage  

SciTech Connect

As part of the Department of Energy’s Applied Battery Research Program, lithium-ion cells of various sizes and chemistries are aged with periodic reference performance tests to ascertain degradation rates. The reference tests included a very slow discharge and charge based on a constant current equal to 1/25th of the rated capacity to elucidate the true electrochemical capacity of the cell. A differential analysis of these data helps to identify the individual kinetic and thermodynamic contributions of the anode and cathode. However, differential curves are very noisy, and previous smoothing methods included simple data reduction and moving averages. This paper introduces an alternative method of finding the differential voltage and differential capacity curves based on radial basis functions. The voltage profile is fit with a number of Gaussian curves, and the resulting model is differentiated. This approach also has the added advantage of assessing model uncertainty based on a bootstrap analysis. The radial basis function method was successfully applied to various lithium-ion chemistries tested under the Applied Battery Research Program. The resulting differential capacity and differential voltage curves were generally smoother than the corresponding curves found by previous methods and also showed little variance, indicating a good model fit. These results imply that the radial basis function technique is a more robust tool for assessing differential data.

Jon P. Christophersen; Steven R. Shaw

2010-02-01

82

Directed differentiation of pluripotent stem cells to functional hepatocytes.  

PubMed

Differentiation of human stem cells to hepatocytes is crucial for industrial applications as well as to develop new therapeutic strategies for liver disease. The protocol described here, using sequentially growth factors known to play a role in liver embryonic development, efficiently differentiates human embryonic stem cells (hESC) as well as human-induced pluripotent stem cells (hiPSC) to hepatocytes by directing them through defined embryonic intermediates, namely, mesendoderm/definitive endoderm and hepatoblast and hepatocyte phenotype. After 28 days, the final differentiated progeny is a mixture of cells, comprising cells with characteristics of hepatoblasts and a smaller cell fraction with morphological and phenotypical features of mature hepatocytes. An extensive functional characterization of the stem cell progeny should be used to confirm that differentiated cells display functional characteristics of mature hepatocytes including albumin secretion, glycogen storage, and several detoxifying functions such as urea production, bilirubin conjugation, glutathione S-transferase activity, cytochrome activity and drug transporter activity. PMID:23546753

Roelandt, Philip; Vanhove, Jolien; Verfaillie, Catherine

2013-01-01

83

Fine structural evidence of mechanoreception in spinal lumbosacral accessory lobes of pigeons  

Microsoft Academic Search

In the lumbosacral spinal cord of birds there are accessory lobes which protrude into the vertebral canal. The accessory lobes consist of multipolar neurons and glia-derived glycogen cells. It has been suggested that these lobes function as a sense organ of equilibrium. Therefore the lobes were studied ultrastructurally to look for possible mechanoreceptive structures. Extracellular lacunae extend from the periphery

Jörg Rosenberg; Reinhold Necker

2000-01-01

84

A peptide from the male accessory glands of the Colorado potato beetle  

Microsoft Academic Search

This thesis describes a study of the male accessory glands of the Colorado potato beetle, Leptinotarsa decemlineata (Say). These glands add various substances to the ejaculate. On mating, the ejaculate is transferred to the female, together with the substances from the male accessory glands. The function of these substances is unknown in the case of the Colorado potato beetle. From

H. M. Smid

1998-01-01

85

Decisions that Make a Difference in Detecting Differential Item Functioning  

ERIC Educational Resources Information Center

|There are numerous statistical procedures for detecting items that function differently across subgroups of examinees that take a test or survey. However, in endeavouring to detect items that may function differentially, selection of the statistical method is only one of many important decisions. In this article, we discuss the important…

Sireci, Stephen G.; Rios, Joseph A.

2013-01-01

86

A note on the automated differentiation of implicit functions  

SciTech Connect

This paper answers the question: Can automated differentiation be used on functions that are defined implicitly, recursively, or iteratively Consider, for example, the simple function x(m) defined by the equation, x(m) {equals} cos(m{center dot}x(m)).

Michelotti, L.

1991-06-27

87

Macrophage differentiation and function in atherosclerosis; opportunities for therapeutic intervention?  

PubMed Central

The macrophage is exquisitely sensitive to its microenvironment, as demonstrated primarily through in vitro study. Changes in macrophage phenotype and function within the atherosclerotic plaque have profound consequences for plaque biology, including rupture and arterial thrombosis leading to clinical events such as myocardial infarction. We review the evidence for dynamic changes in macrophage numbers and macrophage differentiation within the atherosclerotic plaque microenvironment and discuss potential approaches to target macrophage differentiation for therapeutic benefit in cardiovascular disease.

Williams, Howell J.; Fisher, Edward A.; Greaves, David R.

2013-01-01

88

Accessory cell populations in the cornea.  

PubMed

According to the "classical" doctrine, resident cells of the cornea include the stratified epithelial cells, quiescent keratocytes, and a single layer of nondividing endothelial cells. However, it has become increasingly evident that other cell types are involved in the homeostasis of the cornea. The presence of various cell types from different lineages has raised concern among researchers as to what we are actually "seeing" in the cornea. Although definitive conclusions cannot yet be drawn, this review attempts to clarify the various accessory cell types reported in the human and murine cornea. The epithelial layer of the limbal area includes melanocytes, as well as antigen-presenting cells that are also present in the peripheral clear cornea. The most debated tissue currently is perhaps the corneal stroma, where resident keratocytes are not as large a population as was previously believed. Bone marrow-derived cells are found in the cornea, and these may not express the typical HLA molecules usually found on the surface of antigen-presenting cells. Nerve fibers extend though the superficial stroma to form a plexus beneath the epithelium. Although the cell body of the neuron itself is not in the cornea, neural glial cells, such as Schwann cells, are present in the stroma. The use of specific molecular markers and high-quality imaging techniques will be required to fully elucidate the various accessory cells of the cornea and their function. PMID:16681078

Shimmura, Shigeto; Kawakita, Tetsuya

2006-04-01

89

Conservative management of accessory spleen torsion in children.  

PubMed

Accessory spleen torsion is very rare condition especially in children. The aim of this study is to report the conservative treatment option. In April 2009 we observed a 10-year-old child affected by hereditary spherocytosis who reported acute abdominal pain without fever or vomiting. At hospitalization all blood tests were within normal value. Abdominal ultrasounds showed an increase in spleen volume and a solid round-shaped hypoechogenic formation with hyperechogenic areas in the lower pole without vascolarisation on color-Doppler scan. These findings suggested torsion of the accessory spleen. We opted for a conservative approach: analgesics on demand and antibiotics. After a week symptoms resolved spontaneously and patient was discharged in good health conditions. Follow-up ultrasound scans were performed at one week, three-six months and one year after hospitalization and showed a progressive reduction of the dimensions of the solid round-shaped formation. Accessory spleen torsion needs to be added to the differential diagnosis of cases of acute abdomen in children. Ultrasounds with eco-color-Doppler scans seem to be the best option for the diagnosis of such condition in the pediatric age since other diagnostic methods are more invasive and require sedation of patients. Once accessory spleen torsion is correctly diagnosed it is possible to opt for its conservative treatment. PMID:24051978

Scirè, G; Zampieri, N; El-Dalati, G; Camoglio, F S

2013-08-01

90

The LIM protein LIMD1 influences osteoblast differentiation and function.  

PubMed

The balance between bone resorption and bone formation involves the coordinated activities of osteoblasts and osteoclasts. Communication between these two cell types is essential for maintenance of normal bone homeostasis; however, the mechanisms regulating this cross talk are not completely understood. Many factors that mediate differentiation and function of both osteoblasts and osteoclasts have been identified. The LIM protein Limd1 has been implicated in the regulation of stress osteoclastogenesis through an interaction with the p62/sequestosome protein. Here we show that Limd1 also influences osteoblast progenitor numbers, differentiation, and function. Limd1(-/-) calvarial osteoblasts display increased mineralization and accelerated differentiation. While no significant differences in osteoblast number or function were detected in vivo, bone marrow stromal cells isolated from Limd1(-/-) mice contain significantly more osteoblast progenitors compared to wild type controls when cultured ex vivo. Furthermore, we observed a significant increase in nuclear beta-catenin staining in differentiating Limd1(-/-) calvarial osteoblasts suggesting that Limd1 is a negative regulator of canonical Wnt signaling in osteoblasts. These results demonstrate that Limd1 influences not only stress osteoclastogenesis but also osteoblast function and osteoblast progenitor commitment. Together, these data identify Limd1 as a novel regulator of both bone osetoclast and bone osteoblast development and function. PMID:18657804

Luderer, Hilary F; Bai, Shuting; Longmore, Gregory D

2008-06-09

91

The LIM protein LIMD1 Influences Osteoblast Differentiation and Function  

PubMed Central

The balance between bone resorption and bone formation involves the coordinated activities of osteoblasts and osteoclasts. Communication between these two cell types is essential for maintenance of normal bone homeostasis; however, the mechanisms regulating this cross talk are not completely understood. Many factors that mediate differentiation and function of both osteoblasts and osteoclasts have been identified. The LIM protein Limd1 has been implicated in the regulation of stress osteoclastogenesis through an interaction with the p62/sequestosome protein. Here we show that Limd1 also influences osteoblast progenitor numbers, differentiation, and function. Limd1?/?calvarial osteoblasts display increased mineralization and accelerated differentiation. While no significant differences in osteoblast number or function were detected in vivo, bone marrow stromal cells isolated from Limd1?/? mice contain significantly more osteoblast progenitors compared to wild type controls when cultured ex vivo. Furthermore, we observed a significant increase in nuclear ?-catenin staining in differentiating Limd1?/? calvarial osteoblasts suggesting that Limd1 is a negative regulator of canonical Wnt signaling in osteoblasts. These results demonstrate that Limd1 influences not only stress osteoclastogenesis but also osteoblast function and osteoblast progenitor commitment. Together, these data identify Limd1 as a novel regulator of both bone osetoclast and bone osteoblast development and function.

Luderer, Hilary F.; Bai, Shuting; Longmore, Gregory D.

2008-01-01

92

The LIM protein LIMD1 influences osteoblast differentiation and function  

SciTech Connect

The balance between bone resorption and bone formation involves the coordinated activities of osteoblasts and osteoclasts. Communication between these two cell types is essential for maintenance of normal bone homeostasis; however, the mechanisms regulating this cross talk are not completely understood. Many factors that mediate differentiation and function of both osteoblasts and osteoclasts have been identified. The LIM protein Limd1 has been implicated in the regulation of stress osteoclastogenesis through an interaction with the p62/sequestosome protein. Here we show that Limd1 also influences osteoblast progenitor numbers, differentiation, and function. Limd1{sup -/-} calvarial osteoblasts display increased mineralization and accelerated differentiation. While no significant differences in osteoblast number or function were detected in vivo, bone marrow stromal cells isolated from Limd1{sup -/-} mice contain significantly more osteoblast progenitors compared to wild type controls when cultured ex vivo. Furthermore, we observed a significant increase in nuclear {beta}-catenin staining in differentiating Limd1{sup -/-} calvarial osteoblasts suggesting that Limd1 is a negative regulator of canonical Wnt signaling in osteoblasts. These results demonstrate that Limd1 influences not only stress osteoclastogenesis but also osteoblast function and osteoblast progenitor commitment. Together, these data identify Limd1 as a novel regulator of both bone osetoclast and bone osteoblast development and function.

Luderer, Hilary F. [Department of Cell Biology, Washington University School of Medicine, St. Louis, MO (United States); Bai Shuting [Department of Pathology, Washington University School of Medicine, St. Louis, MO (United States); Longmore, Gregory D. [Department of Cell Biology, Washington University School of Medicine, St. Louis, MO (United States); Department of Medicine, Washington University School of Medicine, St. Louis, MO (United States)], E-mail: glongmor@im.wustl.edu

2008-09-10

93

Osteoactivin, an anabolic factor that regulates osteoblast differentiation and function.  

PubMed

Osteoactivin (OA) is a novel glycoprotein that is highly expressed during osteoblast differentiation. Using Western blot analysis, our data show that OA protein has two isoforms, one is transmembranous and the other is secreted into the conditioned medium of primary osteoblasts cultures. Fractionation of osteoblast cell compartments showed that the mature, glycosylated OA isoform of 115 kDa is found in the membranous fraction. Both OA isoforms (secreted and transmembrane) are found in the cytoplasmic fraction of osteoblasts. Overexpression of EGFP-tagged OA in osteoblasts showed that OA protein accumulates into vesicles for transportation to the cell membrane. We examined OA protein production in primary osteoblast cultures and found that OA is maximally expressed during the third week of culture (last stage of osteoblast differentiation). Glycosylation studies showed that OA isoform of 115 kDa is highly glycosylated. We also showed that retinoic acid (RA) stimulates the mannosylation of OA protein. In contrast, tunicamycin (TM) strongly inhibited N-glycans incorporation into OA protein. The functional role of the secreted OA isoform was revealed when cultures treated with anti-OA antibody, showed decreased osteoblast differentiation compared to untreated control cultures. Gain-of-function in osteoblasts using the pBABE viral system showed that OA overexpression in osteoblast stimulated their differentiation and function. The availability of a naturally occurring mutant mouse with a truncated OA protein provided further evidence that OA is an important factor for terminal osteoblast differentiation and mineralization. Using bone marrow mesenchymal cells derived from OA mutant and wild-type mice and testing their ability to differentiate into osteoblasts showed that differentiation of OA mutant osteoblasts was significantly reduced compared to wild-type osteoblasts. Collectively, our data suggest that OA acts as a positive regulator of osteoblastogenesis. PMID:18555216

Abdelmagid, Samir M; Barbe, Mary F; Rico, Mario C; Salihoglu, Sibel; Arango-Hisijara, Israel; Selim, Abdul Hafez; Anderson, Michael G; Owen, Thomas A; Popoff, Steven N; Safadi, Fayez F

2008-03-10

94

Oligodendroglial differentiation induces mitochondrial genes and inhibition of mitochondrial function represses oligodendroglial differentiation.  

PubMed

Demyelination occurs in multiple inherited mitochondrial diseases. We studied which genes were induced as a consequence of differentiation in rodent and human oligodendroglia. Cholesterol, myelin and mitochondrial genes were significantly increased with oligodendroglial differentiation. Mitochondrial DNA content per cell and acetyl CoA-related transcripts increased significantly; thus, the large buildup of cholesterol necessary for myelination appears to require mitochondrial production of acetyl-CoA. Oligodendroglia were treated with low doses of the mitochondrial inhibitor rotenone to test the dependence of differentiation on mitochondrial function. Undifferentiated cells were resistant to rotenone, whereas differentiating cells were much more sensitive. Very low doses of rotenone that did not affect viability or ATP synthesis still inhibited differentiation, as measured by reduced levels of the myelin transcripts 2',3'-Cyclic Nucleotide-3'-Phosphodiesterase and Myelin Basic Protein. Thus, mitochondrial transcripts and mtDNA are amplified during oligodendroglial differentiation, and differentiating oligodendroglia are especially sensitive to mitochondrial inhibition, suggesting mechanisms for demyelination observed in mitochondrial disease. PMID:20005986

Schoenfeld, Robert; Wong, Alice; Silva, Jillian; Li, Ming; Itoh, Aki; Horiuchi, Makoto; Itoh, Takayuki; Pleasure, David; Cortopassi, Gino

2009-12-22

95

Oligodendroglial differentiation induces mitochondrial genes and inhibition of mitochondrial function represses oligodendroglial differentiation  

PubMed Central

Demyelination occurs in multiple inherited mitochondrial diseases. We studied which genes were induced as a consequence of differentiation in rodent and human oligodendroglia. Cholesterol, myelin and mitochondrial genes were significantly increased with oligodendroglial differentiation. Mitochondrial DNA content per cell and acetyl CoA-related transcripts increased significantly; thus, the large buildup of cholesterol necessary for myelination appears to require mitochondrial production of acetyl-CoA. Oligodendroglia were treated with low doses of the mitochondrial inhibitor rotenone to test the dependence of differentiation on mitochondrial function. Undifferentiated cells were resistant to rotenone, whereas differentiating cells were much more sensitive. Very low doses of rotenone that did not affect viability or ATP synthesis still inhibited differentiation, as measured by reduced levels of the myelin transcripts 2?,3?-Cyclic Nucleotide-3?-Phosphodiesterase and Myelin Basic Protein. Thus, mitochondrial transcripts and mtDNA are amplified during oligodendroglial differentiation, and differentiating oligodendroglia are especially sensitive to mitochondrial inhibition, suggesting mechanisms for demyelination observed in mitochondrial disease.

Schoenfeld, Robert; Wong, Alice; Silva, Jillian; Li, Ming; Itoh, Aki; Horiuchi, Makoto; Itoh, Takayuki; Pleasure, David; Cortopassi, Gino

2011-01-01

96

Differential Item Functioning (DIF): Current Problems and Future Directions  

ERIC Educational Resources Information Center

|With the rising concerns over the fairness of language tests, Differential Item Functioning (DIF) has been increasingly applied in bias analysis. Despite its widespread use in psychometric circles, DIF is facing a number of serious problems. This paper is an attempt to shed light on a number of the issues involved in DIF analysis. Specifically,…

Karami, Hossein; Salmani Nodoushan, Mohammad Ali

2011-01-01

97

An Analysis of Differential Item Functioning Based on Calculator Type.  

ERIC Educational Resources Information Center

|The effect of calculator type on student performance on a mathematics examination was studied. Differential item functioning (DIF) methodology was applied to examine group differences (calculator use) on item performance while conditioning on the relevant ability. Other survey questions were developed to ask students the extent to which they used…

Schwarz, Richard; Rich, Changhua; Arenson, Ethan; Podrabsky, Tracy; Cook, Gary

98

Detecting Differential Item Functioning Using Logistic Regression Procedures.  

ERIC Educational Resources Information Center

|A logistic regression model for characterizing differential item functioning (DIF) between two groups is presented. A distinction is drawn between uniform and nonuniform DIF in terms of model parameters. A statistic for testing the hypotheses of no DIF is developed, and simulation studies compare it with the Mantel-Haenszel procedure.…

Swaminathan, Hariharan; Rogers, H. Jane

1990-01-01

99

MIMIC Methods for Assessing Differential Item Functioning in Polytomous Items  

ERIC Educational Resources Information Center

|Three multiple indicators-multiple causes (MIMIC) methods, namely, the standard MIMIC method (M-ST), the MIMIC method with scale purification (M-SP), and the MIMIC method with a pure anchor (M-PA), were developed to assess differential item functioning (DIF) in polytomous items. In a series of simulations, it appeared that all three methods…

Wang, Wen-Chung; Shih, Ching-Lin

2010-01-01

100

Detection of Differential Item Functioning in Multiple Groups.  

ERIC Educational Resources Information Center

|Detection of differential item functioning (DIF) is most often done between two groups of examinees under item response theory. It is sometimes important, however, to determine whether DIF is present in more than two groups. A method is presented for the detection of DIF in multiple groups. The method, the Q(sub j) statistic, is closely related…

Kim, Seock-Ho; And Others

101

Detection of Differential Item Functioning in Multiple Groups.  

ERIC Educational Resources Information Center

|A method is presented for detection of differential item functioning in multiple groups. This method is closely related to F. M. Lord's chi square for comparing vectors of item parameters estimated in two groups. An example is provided using data from 600 college students taking a mathematics test with and without calculators. (SLD)|

Kim, Seock-Ho; And Others

1995-01-01

102

An Analysis of Differential Item Functioning Based on Calculator Type.  

ERIC Educational Resources Information Center

The effect of calculator type on student performance on a mathematics examination was studied. Differential item functioning (DIF) methodology was applied to examine group differences (calculator use) on item performance while conditioning on the relevant ability. Other survey questions were developed to ask students the extent to which they used…

Schwarz, Richard; Rich, Changhua; Arenson, Ethan; Podrabsky, Tracy; Cook, Gary

103

A Comparison of Methods for Detecting Differential Distractor Functioning  

ERIC Educational Resources Information Center

|This study examined the effectiveness of the odds-ratio method (Penfield, 2008) and the multinomial logistic regression method (Kato, Moen, & Thurlow, 2009) for measuring differential distractor functioning (DDF) effects in comparison to the standardized distractor analysis approach (Schmitt & Bleistein, 1987). Students classified as…

Koon, Sharon

2010-01-01

104

Evaluating the Magnitude of Differential Item Functioning in Polytomous Items.  

ERIC Educational Resources Information Center

|Two possible standard error formulas for the polytomous differential item functioning index proposed by N. J. Dorans and A. P. Schmitt (1991) were derived. These standard errors, and associated hypothesis-testing procedures, were evaluated through simulated data. The standard error that performed better is based on N. Mantel's (1963)…

Zwick, Rebecca; Thayer, Dorothy T.

1996-01-01

105

Differential Item Functioning on the Graduate Management Admission Test.  

ERIC Educational Resources Information Center

The purpose of this study was to identify differentially functioning items on operational administrations of the Graduate Management Admission Test (GMAT) through the use of the Mantel-Haenszel statistic. Retrospective analyses of data collected over 3 years are reported for black/white and female/male comparisons for the Verbal and Quantitative…

O'Neill, Kathleen A.; And Others

106

Generalized Mantel-Haenszel Methods for Differential Item Functioning Detection  

ERIC Educational Resources Information Center

|Mantel-Haenszel methods comprise a highly flexible methodology for assessing the degree of association between two categorical variables, whether they are nominal or ordinal, while controlling for other variables. The versatility of Mantel-Haenszel analytical approaches has made them very popular in the assessment of the differential functioning

Fidalgo, Angel M.; Madeira, Jaqueline M.

2008-01-01

107

IRT Differential Item Functioning: An Examination of Ability Scale Purifications.  

ERIC Educational Resources Information Center

Item response theory (IRT) differential item functioning (DIF) methods used to determine the accuracy of item classification as biased or unbiased were studied. Results from simulations show that the iterative linking and ability scale purification method can be more effective than iterative linking alone primarily by reducing false negatives.…

Lautenschlager, Gary J.; And Others

1994-01-01

108

The method of averaging and functional differential equations with delay  

Microsoft Academic Search

We present a natural extension of the method of averaging to fast oscillating functional differential equations with delay. Unlike the usual approach where the analysis is kept in an infinite-dimensional Banach space, our analysis is achieved in Rn. Our results are formulated in classical mathematics. They are proved within Internal Set Theory which is an axiomaticdesc ription of nonstandard analysis.

Mustapha Lakrib

2001-01-01

109

DIFAS: Differential Item Functioning Analysis System. Computer Program Exchange  

ERIC Educational Resources Information Center

|Differential item functioning (DIF) is an important consideration in assessing the validity of test scores (Camilli & Shepard, 1994). A variety of statistical procedures have been developed to assess DIF in tests of dichotomous (Hills, 1989; Millsap & Everson, 1993) and polytomous (Penfield & Lam, 2000; Potenza & Dorans, 1995) items. Some of…

Penfield, Randall D.

2005-01-01

110

A Comparison of Methods for Detecting Differential Distractor Functioning  

ERIC Educational Resources Information Center

This study examined the effectiveness of the odds-ratio method (Penfield, 2008) and the multinomial logistic regression method (Kato, Moen, & Thurlow, 2009) for measuring differential distractor functioning (DDF) effects in comparison to the standardized distractor analysis approach (Schmitt & Bleistein, 1987). Students classified as participating…

Koon, Sharon

2010-01-01

111

Accessory origin of the piriformis muscle.  

PubMed

Incidental finding of an accessory slip of the piriformis muscle in the gluteal region is reported. Following routine dissection of the gluteal region in three formalin-fixed cadavers, an accessory slip of the piriformis was observed. The accessory slip was cleaned, attachments were identified, and dimensions were measured in two parts as fleshy and tendinous parts with a graduated scale to the nearest millimetre. The accessory slip was innervated by a small twig from the sciatic nerve. Having considered the available literature, the accessory slip of piriformis is rare, and if found, could be a cause for the undiagnosed chronic pain in the back and gluteal region, as this accessory slip may compress the sciatic nerve. PMID:18756338

Ravindranath, Y; Manjunath, K Y; Ravindranath, R

2008-08-01

112

Altered functional differentiation of mesoangioblasts in a genetic myopathy.  

PubMed

Mutations underlying genetic cardiomyopathies might affect differentiation commitment of resident progenitor cells. Cardiac mesoangioblasts (cMabs) are multipotent progenitor cells resident in the myocardium. A switch from cardiac to skeletal muscle differentiation has been recently described in cMabs from ?-sarcoglycan-null mice (?SG(-/-)), a murine model of genetic myopathy with early myocardial involvement. Although complementation with ?SG gene was inconsequential, knock-in of miRNA669a (missing in ?SG(-/-) cMabs) partially rescued the mutation-induced molecular phenotype. Here, we undertook a detailed evaluation of functional differentiation of ?SG(-/-) cMabs and tested the effects of miRNA669a-induced rescue in vitro. To this end, cMabs were compared with neonatal cardiomyocytes (CMs) and skeletal muscle C2C12 cells, representative of cardiac and skeletal muscle respectively. Consistent with previous data on molecular patterns, electrophysiological and Ca(2+)-handling properties of ?SG(-/-) cMabs were closer to C2C12 cells than to CM ones. Nevertheless, subtler aspects, including action potential contour, Ca(2+)-spark properties and RyR isoform expression, distinguished ?SG(-/-) cMabs from C2C12 cells. Contrary to previous reports, wild-type cMabs failed to show functional differentiation towards either cell type. Knock-in of miRNA669a in ?SG(-/-) cMabs rescued the wild-type functional phenotype, i.e. it completely prevented development of skeletal muscle functional responses. We conclude that miRNA669a expression, ablated by ?SG deletion, may prevent functional differentiation of cMabs towards the skeletal muscle phenotype. PMID:23387296

Altomare, Claudia; Barile, Lucio; Rocchetti, Marcella; Sala, Luca; Crippa, Stefania; Sampaolesi, Maurilio; Zaza, Antonio

2013-02-07

113

Can Differential Rapid-Guessing Behavior Lead to Differential Item Functioning?  

Microsoft Academic Search

This investigation examined whether different rates of rapid guessing between groups could lead to detectable levels of differential item functioning (DIF) in situations where the item parameters were the same for both groups. Two simulation studies were designed to explore this possibility. The groups in Study 1 were simulated to reflect differences between high-stakes and low-stakes conditions, with no rapid

Christine E. DeMars; Steven L. Wise

2010-01-01

114

21 CFR 890.5925 - Traction accessory.  

Code of Federal Regulations, 2013 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory. (a) Identification. A...

2013-04-01

115

Engine starter and accessory drive system  

SciTech Connect

An engine starter and accessory drive system is described which consists of: an accessory drive means; a planetary gearset having a sun gear driveably connected to the accessory drive means, a ring gear, a carrier and planet pinions rotatably mounted on the carrier, fixed to the engine crankshaft, meshing with the sun gear and with the ring gear; means for holding the ring gear against rotation; and a starter motor and first clutch means for providing a one-way driving connection between the motor and the accessory drive means.

Stockton, T.R.

1986-10-07

116

Pitfall of the accessory spleen.  

PubMed

Two patients, one with insulinoma and one with Cushing's syndrome, are presented. Biochemical evaluation readily suggested the correct diagnosis. During radiologic imaging, the anatomic abnormality giving rise to these diseases, i.e. a pancreatic islet cell tumor, and an adrenal adenoma, at first were mistakenly interpreted as an accessory spleen on the basis of specific computed tomography and magnetic resonance imaging appearances. The insulinoma was identified as such during laparotomy, whereas additional jodo-cholesterol scintigraphy revealed the real nature of the lesion in the patient with Cushing's syndrome. Both patients were operated successfully. PMID:10727761

Sels, J P; Wouters, R M; Lamers, R; Wolffenbuttel, B H

2000-04-01

117

Mechanical accessories for mobile teleoperators  

SciTech Connect

The choice of optimum mechanical accessories for mobile teleoperators involves matching the criteria for emergency response with the available technology. This paper presents a general background to teleoperations, a potpourri of the manipulator systems available, and an argument for force reflecting manipulation. The theme presented is that the accomplishment of humanlike endeavors in hostile environments will be most successful when man model capabilities are utilized. The application of recent electronic technology to manipulator development has made new tools available to be applied to emergency response activities. The development activities described are products of the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory. 13 refs., 7 figs.

Feldman, M.J.; Herndon, J.N.

1985-01-01

118

Differentiation  

NSDL National Science Digital Library

In the five parts of this video, we define the derivative and then build a cribsheet of rules for expressing the slopes of simple functions and combinations of functions. These include the power rule, the chain rule, the product and quotient rules, and the rules for differentiating sinusoidal functions.

Liao, David

119

The sea lamprey has a primordial accessory olfactory system  

PubMed Central

Background A dual olfactory system, represented by two anatomically distinct but spatially proximate chemosensory epithelia that project to separate areas of the forebrain, is known in several classes of tetrapods. Lungfish are the earliest evolving vertebrates known to have this dual system, comprising a main olfactory and a vomeronasal system (VNO). Lampreys, a group of jawless vertebrates, have a single nasal capsule containing two anatomically distinct epithelia, the main (MOE) and the accessory olfactory epithelia (AOE). We speculated that lamprey AOE projects to specific telencephalic regions as a precursor to the tetrapod vomeronasal system. Results To test this hypothesis, we characterized the neural circuits and molecular profiles of the accessory olfactory epithelium in the sea lamprey (Petromyzon marinus). Neural tract-tracing revealed direct and reciprocal connections with the dorsomedial telencephalic neuropil (DTN) which in turn projects directly to the dorsal pallium and the rostral hypothalamus. High-throughput sequencing demonstrated that the main and the accessory olfactory epithelia have virtually identical profiles of expressed genes. Real time quantitative PCR confirmed expression of representatives of all 3 chemoreceptor gene families identified in the sea lamprey genome. Conclusion Anatomical and molecular evidence shows that the sea lamprey has a primordial accessory olfactory system that may serve a chemosensory function.

2013-01-01

120

Three Accessories for a Rotating Platform.  

ERIC Educational Resources Information Center

|Describes three accessories developed to be used in conjunction with the rotating platform or turntable. Three demonstrations using these accessories are included. These demonstrations are: (a) conservation of angular momentum; (b) gravity-defying goblets; and (c) direct measurement of centripetal force. (HM)|

Riley, James A.; Fryer, Oscar G.

1980-01-01

121

Laguerre series solution of a functional differential equation  

Microsoft Academic Search

This paper presents a Laguerre series method for the solution of a functional differential equation of the type (d\\/dt)y(t) = Ay(?t) + By(t), with given initial conditions. The method consists of the following steps : (1) represent y(t) and y(?t), respectively, by series of the Laguerre polynomials gi(t) and gi(?t) ; (2) expand gi(?t) into Laguerre series of gi(t) ;

CHYI HWANG; YEN-PING SHIH

1982-01-01

122

Exp-Function Method for Solving Fractional Partial Differential Equations  

PubMed Central

We extend the Exp-function method to fractional partial differential equations in the sense of modified Riemann-Liouville derivative based on nonlinear fractional complex transformation. For illustrating the validity of this method, we apply it to the space-time fractional Fokas equation and the nonlinear fractional Sharma-Tasso-Olver (STO) equation. As a result, some new exact solutions for them are successfully established.

2013-01-01

123

Molecular orchestration of differentiation and function of regulatory T cells  

PubMed Central

During the last decade, a unique mechanism of negative regulation of immune responses and inflammation by a dedicated population of so-called regulatory T cells (Treg) has become a focus of intensive investigation. Through the discovery of transcription factor Foxp3 as a central molecular determinant of differentiation and function of Treg cells, the complex biology of these cells, including maintenance of immunological tolerance to “self” and regulation of immune responses to pathogens, commensals, and tumors, has become amenable to mechanistic studies. In this review, we discuss the molecular aspects of Treg cell lineage commitment, maintenance, and function.

Lu, Li-Fan; Rudensky, Alexander

2009-01-01

124

Calcium receptor message, expression and function decrease in differentiating keratinocytes.  

PubMed

Calcium-sensing receptor (CaSR) expression and function were studied in proliferating and differentiating cultured human gingival keratinocytes (HGKs). CaSR mRNA and protein were present in proliferating HGKs cultured in 0.03 mM [Ca(2+)] and decreased in cells induced to differentiate by culturing in 1.2 mM [Ca(2+)] for 2 days. CaSR protein was also detected in gingival tissue. Exposure to 10 mM extracellular [Ca(2+)] activated two sequential whole-cell currents. The first was a small, transient calcium release activated calcium current I(CRAC)-like current with an inwardly rectifying I-V curve. The second current was larger with a linear I-V curve. Both currents were significantly decreased in differentiating cells. Neither neomycin nor gadolinium induced changes in whole cell currents nor in intracellular [Ca(2+)], but neomycin inhibited the late large current. Extracellular Ca(2+) increased intracellular [Ca(2+)] of proliferating HGKs in a dose-dependent fashion. Comparison of the time-courses of the whole-cell currents and the intracellular [Ca(2+)] responses indicated both induced currents supported a Ca(2+) influx. Extracellular [Mg(2+)] changes did not affect intracellular [Ca(2+)]. La(3+) and 2-APB inhibited the whole cell current and intracellular [Ca(2+)] changes. The results indicate that the CaSR signaling response likely plays a major role in initiating Ca(2+) induced differentiation responses in HGKs. PMID:14770313

Fatherazi, Sahba; Belton, Carol M; Cai, Shiwei; Zarif, Shukriya; Goodwin, Paul C; Lamont, Richard J; Izutsu, Kenneth T

2004-02-10

125

Stability results for systems described by coupled retarded functional differential equations and functional difference equations  

Microsoft Academic Search

In this work stability results for systems described by coupled Retarded Functional Differential Equations (RFDEs) and Functional Difference Equations (FDEs) are presented. The results are based on the observation that the composite system can be regarded as the feedback interconnection of a subsystem described by RFDEs and a subsystem described by FDEs. Recent small-gain results and Lyapunov-like characterizations of the

Iasson Karafyllis; Pierdomenico Pepe; Zhong-Ping Jiang

2009-01-01

126

Epigenetic regulation of NK cell differentiation and effector functions  

PubMed Central

Upon maturation, natural killer (NK) cells acquire effector functions and regulatory receptors. New insights suggest a considerable functional heterogeneity and dynamic regulation of receptor expression in mature human NK cell subsets based on different developmental axes. Such processes include acquisition of lytic granules as well as regulation of cytokine production in response to exogenous cytokine stimulation or target cell interactions. One axis is regulated by expression of inhibitory receptors for self-MHC class I molecules, whereas other axes are less well defined but likely are driven by different activating receptor engagements or cytokines. Moreover, the recent identification of long-lived NK cell subsets in mice that are able to expand and respond rapidly following a secondary viral challenge suggest previously unappreciated plasticity in the programming of NK cell differentiation. Here, we review advances in our understanding of mature NK cell development and plasticity with regards to regulation of cellular function. Furthermore, we highlight some of the major questions that remain pertaining to the epigenetic changes that underlie the differentiation and functional specialization of NK cells and the regulation of their responses.

Cichocki, Frank; Miller, Jeffrey S.; Anderson, Stephen K.; Bryceson, Yenan T.

2013-01-01

127

The Epigenetic Landscape of Mammary Gland Development and Functional Differentiation  

PubMed Central

Most of the development and functional differentiation in the mammary gland occur after birth. Epigenetics is defined as the stable alterations in gene expression potential that arise during development and proliferation. Epigenetic changes are mediated at the biochemical level by the chromatin conformation initiated by DNA methylation, histone variants, post-translational modifications of histones, non-histone chromatin proteins, and non-coding RNAs. Epigenetics plays a key role in development. However, very little is known about its role in the developing mammary gland or how it might integrate the many signalling pathways involved in mammary gland development and function that have been discovered during the past few decades. An inverse relationship between marks of closed (DNA methylation) or open chromatin (DnaseI hypersensitivity, certain histone modifications) and milk protein gene expression has been documented. Recent studies have shown that during development and functional differentiation, both global and local chromatin changes occur. Locally, chromatin at distal regulatory elements and promoters of milk protein genes gains a more open conformation. Furthermore, changes occur both in looping between regulatory elements and attachment to nuclear matrix. These changes are induced by developmental signals and environmental conditions. Additionally, distinct epigenetic patterns have been identified in mammary gland stem and progenitor cell sub-populations. Together, these findings suggest that epigenetics plays a role in mammary development and function. With the new tools for epigenomics developed in recent years, we now can begin to establish a framework for the role of epigenetics in mammary gland development and disease.

Rijnkels, Monique; Kabotyanski, Elena; Montazer-Torbati, Mohamad B.; Beauvais, C. Hue; Vassetzky, Yegor; Rosen, Jeffrey M.; Devinoy, Eve

2010-01-01

128

Requirement for functional BK channels in maintaining oscillation in venomotor tone revealed by species differences in expression of the ?1 accessory subunits.  

PubMed

We determined the possible role of large-conductance Ca2+-activated K (BK) channels in regulation of venous tone in small capacitance veins and blood pressure. In rat mesenteric venous smooth muscle cells (MV SMC), BK channel ?- and ?1-subunits were coexpressed, unitary BK currents were detected, and single-channel currents were sensitive to voltage and [Ca2+]i. Rat MV SMCs displayed Ca sparks and iberiotoxin-sensitive spontaneous transient outward currents. Under resting conditions in vitro, rat MV exhibited nifedipine-sensitive spontaneous oscillatory constrictions. Blockade of BK channels by paxilline and Ca2+ sparks by ryanodine constricted rat MV. Nifedipine caused venodilation and blocked paxilline-induced, KCl-induced (20 mM), and BayK8644-induced contraction. Acute inhibition of BK channels with iberiotoxin in vivo increased blood pressure and reduced venous capacitance, measured as an increase in mean circulatory filling pressure in conscious rats. BK channel ?-subunits and L-type Ca2+ channel ?1-C subunits are expressed in murine MV. However, these channels are not functional because murine MV lack nifedipine-sensitive basal tone and rhythmic constrictions. Murine MV were also insensitive to paxilline, ryanodine, KCl, and BayK8644, consistent with our previous studies showing that murine MV do not have BK ?1-subunits. These data show that not only there are species-dependent properties in ion channel control of venomotor tone but also BK channels are required for rhythmic oscillations in venous tone. PMID:21885988

Xu, Hui; Kandlikar, Sachin S; Westcott, Erika B; Fink, Gregory D; Galligan, James J

2012-01-01

129

Accessory cell defect in unresponsiveness of neonates and aged to polysaccharide vaccines.  

PubMed

T independent antigens elicit antibody responses in the absence of carrier specific T helper cells but require signals from accessory cells (macrophages and dendritic cells) or specific cytokines. They are further subdivided into TI-1 and TI-2 categories based on the ability of TI-1 but not TI-2 antigens to elicit immune responses from neonates. Most bacterial polysaccharides including the pneumococcal polysaccharide vaccines belong to the TI-2 class. It is hypothesized that defects in accessory cell function play a critical role in the failure of neonates to respond to such TI-2 antigens. Immune responses to these TI-2 stimuli are also reduced in the aged, also due to a quantitative deficiency in accessory cells. Agents that can stimulate accessory cell function may provide an alternative strategy to improve the immunogenicity of the polysaccharide vaccines in the neonates and the aged. PMID:11027821

Bondada, S; Wu, H; Robertson, D A; Chelvarajan, R L

2000-10-15

130

HIV-1 gp120 modulates the immunological function and expression of accessory and co-stimulatory molecules of monocyte-derived dendritic cells.  

PubMed

Initiation of a primary immune response requires antigen specific CD4(+) T helper (T(h)) cells to assist in priming of CD8(+) cytotoxic T cell (CTL) activity. This is optimal when T(h) cells and CTL recognize antigen when presented to them by a dendritic cell (DC) in the context of major histocompatibility complex (MHC) class I and class II complexes. We have hypothesized that human DC exposed to HIV-1 gp120 IIIB envelope glycoprotein may activate or alter the immunological activation of DCs. Our findings have led us to conclude that HIV-1 gp120 LAV/IIIB activates monocyte-derived DC when they are in their immature state while HIV-1 gp120 exhibits highly selective effects on mature DC. We have observed that following maturation of DCs with lipopolysaccharide (LPS) that they are less susceptible to the modulatory effects of gp120. Although HIV-1 gp120 activates immature DC, it does so in a manner that abrogates their normal function in host immune responses and consequently disturbs the homeostatic balance of host immune response to infection. We suggest that HIV-1 gp120 may support sustained productive infection and transinfection of activated T cells that cluster with gp120-activated DC. We believe that these are promoted by mechanisms that are dependent, at least in part, on altered cytokine responses, enhanced expression of cellular adhesion molecules and augmented DC-mediated activation of T cells in nonspecific and antigen-specific immune reactivities. Consequently, HIV-1 gp120 may actively contribute to the immunopathogenesis of AIDS. PMID:12427289

Williams, Marc A; Trout, Rodney; Spector, Stephen A

2002-10-01

131

Heterogeneity in the differentiation and function of memory B cells.  

PubMed

Vaccines that induce neutralizing antibodies have led to the eradication of small pox and have severely reduced the prevalence of many other infections. However, even the most successful vaccines do not induce protective antibodies in all individuals, and can fail to induce lifelong immunity. A key to remedying these shortcomings may lie in a better understanding of long-lived memory B cells. Recent studies have revealed novel insights into the differentiation and function of these cells, and have shown that the memory B cell pool is much more heterogeneous than previously appreciated. PMID:22920843

Taylor, Justin J; Jenkins, Marc K; Pape, Kathryn A

2012-08-21

132

Functional role of Rho-kinase in ameloblast differentiation.  

PubMed

During tooth development, inner enamel epithelial (IEE) cells differentiate into enamel-secreting ameloblasts, a polarized and elongated cellular population. The molecular underpinnings of this morphogenesis and cytodifferentiation, however, are not well understood. Here, we show that Rho-associated coiled-coil-containing protein kinase (ROCK) regulates ameloblast differentiation and enamel formation. In mouse incisor organ cultures, inhibition of ROCK, hindered IEE cell elongation and disrupted polarization of differentiated ameloblasts. Expression of enamel matrix proteins, such as amelogenin and ameloblastin, and formation of the terminal band structure of actin and E-cadherin were also perturbed. Cultures of dental epithelial cells revealed that ROCK regulates cell morphology and cell adhesion through localization of actin bundles, E-cadherin, and ?-catenin to cell membranes. Moreover, inhibition of ROCK promoted cell proliferation. Small interfering RNA specific for ROCK1 and ROCK2 demonstrated that the ROCK isoforms performed complementary functions in the regulation of actin organization and E-cadherin-mediated cell-cell adhesion. Thus, our results have uncovered a novel role for ROCK in amelogenesis. PMID:21792909

Otsu, Keishi; Kishigami, Ryota; Fujiwara, Naoki; Ishizeki, Kiyoto; Harada, Hidemitsu

2011-10-01

133

Controlled Speed Accessory Drive Demonstration Program.  

National Technical Information Service (NTIS)

A Controlled Speed Accessory Drive System was examined in an effort to improve the fuel economy of passenger cars. Concept feasibility and the performance of a typical system during actual road driving conditions were demonstrated. The CSAD system is desc...

F. W. Hoehn

1981-01-01

134

21 CFR 890.3910 - Wheelchair accessory.  

Code of Federal Regulations, 2010 CFR

...MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910 Wheelchair accessory. (a) Identification...suspension sling, head and trunk support, and blanket and leg rest strap. (b) Classification. Class I...

2006-04-01

135

21 CFR 890.3910 - Wheelchair accessory.  

Code of Federal Regulations, 2010 CFR

...MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910 Wheelchair accessory. (a) Identification...suspension sling, head and trunk support, and blanket and leg rest strap. (b) Classification. Class I...

2008-04-01

136

21 CFR 890.3910 - Wheelchair accessory.  

Code of Federal Regulations, 2010 CFR

...MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910 Wheelchair accessory. (a) Identification...suspension sling, head and trunk support, and blanket and leg rest strap. (b) Classification. Class I...

2005-04-01

137

21 CFR 890.3910 - Wheelchair accessory.  

Code of Federal Regulations, 2013 CFR

...MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910 Wheelchair accessory. (a) Identification...suspension sling, head and trunk support, and blanket and leg rest strap. (b) Classification. Class I...

2013-04-01

138

One nose, one brain: contribution of the main and accessory olfactory system to chemosensation  

PubMed Central

The accessory olfactory system is present in most tetrapods. It is involved in the perception of chemical stimuli, being implicated also in the detection of pheromones. However, it is sensitive also to some common odorant molecules, which have no clear implication in intraspecific chemical communication. The accessory olfactory system may complement the main olfactory system and may contribute different perceptual features to the construction of a unitary representation, which merges the different chemosensory qualities. Crosstalk between the main and accessory olfactory systems occurs at different levels of central processing, in brain areas where the inputs from the two systems converge. Interestingly, centrifugal projections from more caudal brain areas are deeply involved in modulating both main and accessory sensory processing. A high degree of interaction between the two systems may be conceived and partial overlapping appears to occur in many functions. Therefore, the central chemosensory projections merge inputs from different organs to obtain a complex chemosensory picture.

Mucignat-Caretta, Carla; Redaelli, Marco; Caretta, Antonio

2012-01-01

139

Rare association in a female DSD case of phallus, accessory phallic urethra, perineal lipoma and anterior ectopic anus.  

PubMed

Disorders of sex differentiation (DSD) are a heterogeneous and broad spectrum group of diseases with a varied appearance. Presence of an accessory phallus with a phallic urethra in association with a normal vagina in a female is an extremely uncommon anomaly. We present a rare case of a genotypically female child with a normal urethra and vagina in association with a phallus, accessory phallic urethra, perineal lipoma and anterior ectopic anus. PMID:22836203

Mahalik, Santosh Kumar; Mahajan, Jai Kumar; Sodhi, Kushaljit Singh; Garge, Saurabh; Vaiphei, Kim; Rao, Kattragadda L

2012-07-24

140

Honokiol inhibits osteoclast differentiation and function in vitro.  

PubMed

Honokiol, a neolignan, is a physiologically active component of kouboku (Magnolia obovata), a herb used in traditional Chinese medicine. This study investigated the effects of honokiol on the differentiation and function of osteoclasts induced by receptor activator of nuclear factor-kappaB ligand (RANKL). Honokiol markedly inhibited RANKL-induced tartrate-resistant acid phosphatase (TRAP) activity and the formation of TRAP-positive multinucleated cells in both bone marrow-derived monocytes and RAW264 cells. In experiments to elucidate its mechanism of action, honokiol was found to suppress RANKL-induced phosphorylation of p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). The RANKL-induced expressions of c-Fos and nuclear factor of activated T cells-c1 (NFATc1), which are crucial transcriptional factors for osteoclastogenesis, were also reduced by treatment with honokiol. Furthermore, honokiol induced disruption of the actin rings in mature osteoclasts (mOCs) without affecting the cell viability and suppressed osteoclastic pit formation on dentin slices. Taken together, these results suggest that honokiol inhibits osteoclast differentiation by suppressing the activation of MAPKs (p38 MAPK, ERK and JNK), decreasing the expressions of c-Fos and NFATc1, and attenuates bone resorption by disrupting the actin rings in mOCs. Therefore, honokiol could prove useful for the treatment of bone diseases associated with excessive bone resorption. PMID:20190414

Hasegawa, Shin-Ichi; Yonezawa, Takayuki; Ahn, Jae-Yong; Cha, Byung-Yoon; Teruya, Toshiaki; Takami, Masamichi; Yagasaki, Kazumi; Nagai, Kazuo; Woo, Je-Tae

2010-01-01

141

Current understanding of Th2 cell differentiation and function.  

PubMed

Helper T cell (Th) has been identified as a critical immune cell for regulating immune response since 1980s. The type 2 helper Tcell (Th2), characterized by the production of interleukin-4 (IL-4), IL-5 and IL-13, plays a critical role in immune response against helminths invading cutaneous or mucosal sites. It also has a functional role in the pathophysiology of allergic diseases such as asthma and allergic diarrhea. Currently, most studies have shed light on Th2 cell function and behavior in specific diseases, such as asthma and helminthes inflammation, but not on Th2 cell itself and its differentiation. Based on different cytokines and specific behavior in recent research, Th2 cell is also regarded as new subtypes of T cell, such as IL-9 secreting T cell (Th9) and CXCR5(+) T follicular helper cells. Here, we will discuss the latest view of Th2 cell towards their function and the involvement of Th2 cell in diseases. PMID:21904976

Li, Zhenhu; Zhang, Yuan; Sun, Bing

2011-09-09

142

MicroRNA control of lymphocyte differentiation and function  

PubMed Central

Summary MicroRNAs (miRNAs) are a class of endogenous, non-coding regulatory RNAs that control gene regulation by guiding silencing protein complexes to mRNA in a sequence-dependent manner. In this way miRNAs are able to repress gene expression post-transcriptionally by affecting mRNA stability or translation. These ubiquitous molecules play central roles in a wide range of biological processes, including cell proliferation, differentiation and apoptosis. Within the context of the immune system, genetic studies have identified distinct roles for specific miRNAs in gene regulation during development, activation and maturation. Conversely, dysregulation of miRNA expression has been specifically correlated with cancer. This review outlines our current understanding of miRNA function in lymphocytes as it impacts expression of protein-coding genes in the context of proper development, as well as oncogenesis.

Belver, Laura; Papavasiliou, Nina F; Ramiro, Almudena R

2011-01-01

143

Differential executive functioning performance by phase of bipolar disorder  

PubMed Central

Objective This study examined the influence of illness phase on executive functioning performance using factor-derived cognitive scores in a cross-sectional design. Methods Healthy control (HC) subjects (n = 57), and euthymic (E-BD) (n = 117), depressed (D-BD) (n = 73), and hypomanic/mixed (HM/M-BD) (n = 26) patients with bipolar disorder (BD) were evaluated using executive functioning measures (Wisconsin Card Sorting Test, Trail Making Test–Parts A and B, Verbal Fluency, Parametric Go/No-Go, Stroop, and Digit Symbol) comprising Conceptual Reasoning and Set-Shifting (CRSS), Processing Speed with Interference Resolution (PSIR), Verbal Fluency and Processing Speed (VFPS), and Inhibitory Control (IC) factor scores. Results Two of the four executive functioning factors were significantly different between groups based upon phase of illness. The HM/M group was significantly worse than both of the other BD groups and the HC group in IC. The VFPS factor was sensitive to the active phase of BD, with the HM/M-BD and D-BD groups worse than HC. Extending our prior work, the PSIR factor, and now the CRSS factor were significantly worse in BD relative to HC, irrespective of phase of illness. Conclusions Phase of illness had differential cognitive profiles in executive functioning factors, even after considering and excluding the impact of clinical features, illness characteristics, medications, and demographics. Consolidating executive functioning tasks into reliable factor scores provides unique information to measure and define cognitive deficiencies throughout phases of BD, and to measure intermediate phenotypes in BD, and may aid in tracking and clarifying treatment focus.

Ryan, Kelly A; Vederman, Aaron C; McFadden, E Michelle; Weldon, Anne L; Kamali, Masoud; Langenecker, Scott A; McInnis, Melvin G

2013-01-01

144

Assessing Gender-Related Differential Item Functioning and Predictive Validity with the Institutional Integration Scale  

ERIC Educational Resources Information Center

|This study examined the gender-related differential predictive validity of five subscales of the Institutional Integration Scale (IIS) with regard to college student withdrawal. Differential functioning of the IIS across genders was assessed using an item response theory (IRT)-based framework of differential item and test functioning. The results…

Baker, Becca A.; Caison, Amy L.; Meade, Adam W.

2007-01-01

145

Computations Involving Differential Operators and Their Actions on Functions.  

National Technical Information Service (NTIS)

The algorithms derived by Grossmann and Larson (1989) are further developed for rewriting expressions involving differential operators. The differential operators involved arise in the local analysis of nonlinear dynamical systems. These algorithms are ex...

P. E. Crouch R. Grossman R. Larson

1991-01-01

146

Middle East respiratory syndrome coronavirus accessory protein 4a is a type I interferon antagonist.  

PubMed

Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe acute respiratory infection with as yet unclear epidemiology. We previously showed that MERS-CoV counteracts parts of the innate immune response in human bronchiolar cells. Here we analyzed accessory proteins 3, 4a, 4b, and 5 for their abilities to inhibit the type I interferon response. Accessory protein 4a was found to block interferon induction at the level of melanoma differentiation-associated protein 5 (MDA5) activation presumably by direct interaction with double-stranded RNA. PMID:24027320

Niemeyer, Daniela; Zillinger, Thomas; Muth, Doreen; Zielecki, Florian; Horvath, Gabor; Suliman, Tasnim; Barchet, Winfried; Weber, Friedemann; Drosten, Christian; Müller, Marcel A

2013-09-11

147

Homogeneous feedback design of differential inclusions based on control Lyapunov functions  

NASA Astrophysics Data System (ADS)

An improved formula of controllers based on control Lyapunov functions is presented.A homogeneous controller of homogeneous differential inclusions is designed.A homogeneous controller of differential inclusions with uncertainties is constructed.

Zhang, Junfeng; Han, Zhengzhi; Huang, Jun

2013-10-01

148

Wavefront sensing with the differential optical transfer function  

NASA Astrophysics Data System (ADS)

Recently a new technique for estimating the complex field in the pupil of a telescope from image-plane intensity measurements has been introduced by Codona.1, 2 The simplest form of the method uses two images of a point source, one with a small modification introduced in the pupil. The algorithm to recover the pupil field uses a functional derivative of the optical transfer function (OTF), and is simple and non-iterative. The derivative is approximated empirically by the difference between the Fourier transforms of the two PSFs: the differential OTF or dOTF. In keeping with the Hermitian symmetry of the OTF, the dOTF includes two conjugate copies of the pupil field overlapping at the point of modification. By placing the modification near the edge of the pupil, the overlap region can be kept small. It can be eliminated altogether by using a second modification and a third image. The technique can be used in broadband light, at the cost of blurring in the recovered phase that is proportional to the fractional bandwidth. Although the dOTF is unlikely to find application in high frame rate astronomical adaptive optics, it has many potential uses such as optical shop testing, non-common-path wavefront error estimation, segmented telescope phasing and general imaging system diagnostics. In this paper, we review the dOTF concept, theory, and initial experiments to demonstrate the technique.

Hart, Michael; Codona, Johanan L.

2012-10-01

149

Structure and diversity in mammalian accessory olfactory bulb.  

PubMed

The accessory olfactory bulb (AOB) is the first neural integrative center for the olfactory-like vomeronasal sensory system. In this article, we first briefly present an overview of vomeronasal system organization and review the history of the discovery of mammalian AOB. Next, we briefly review the evolution of the vomeronasal system in vertebrates, in particular the reptiles. Following these introductory aspects, the structure of the rodent AOB, as typical of the well-developed mammalian AOB, is presented, detailing laminar organization and cell types as well as aspects of the homology with the main olfactory bulb. Then, the evolutionary origin and diversity of the AOB in mammalian orders and species is discussed, describing structural, phylogenetic, and species-specific variation in the AOB location, shape, and size and morphologic differentiation and development. The AOB is believed to be absent in fishes but present in terrestrial tetrapods including amphibians; among the reptiles AOB is absent in crocodiles, present in turtles, snakes, and some lizards where it may be as large or larger than the main bulb. The AOB is absent in bird and in the aquatic mammals (whales, porpoises, manatees). Among other mammals, AOB is present in the monotremes and marsupials, edentates, and in the majority of the placental mammals like carnivores, herbivores, as well as rodents and lagomorphs. Most bat species do not have an AOB and among those where one is found, it shows marked variation in size and morphologic development. Among insectivores and primates, AOB shows marked variation in occurrence, size, and morphologic development. It is small in shrews and moles, large in hedgehogs and prosimians; AOB continues to persist in New World monkeys but is not found in the adults of the higher primates such as the Old World monkeys, apes, and humans. In many species where AOB is absent in the adult, it often develops in the embryo and fetus but regresses in later stages of development. Finally, new areas in vomeronasal system research such as the diversity of receptor molecules and the regional variation in receptor neuron type as well as in the output neurons of the AOB and their projection pathways are briefly discussed. In view of the pronounced diversity of size, morphologic differentiation, and phylogenetic development, the need to explore new functions for the vomeronasal system in areas other than sexual and reproductive behaviors is emphasized. PMID:9880163

Meisami, E; Bhatnagar, K P

1998-12-15

150

Gamma probe-confirmed laparoscopic accessory splenectomy.  

PubMed

The simultaneous occurrence of idiopathic thrombocytopenic purpura (ITP) and Hodgkin's disease in the same patient is uncommon. There have been only a limited number of reported cases of newly diagnosed ITP following Hodgkin's disease. Even more uncommon is the development of ITP after splenectomy for Hodgkin's disease. Of the reported cases of ITP following splenectomy for Hodgkin's disease, all have been successfully treated with medical therapy. We report an unusual case of an accessory spleen causing ITP in a patient who had undergone a splenectomy for Hodgkin's disease 10 years earlier. The patient underwent hand-held gamma-probe-assisted laparoscopic accessory splenectomy. PMID:12296313

Hendrickson, R J; Koniaris, L G; Kovach, S J; Johnson, J A

2002-09-01

151

Improvement in Detection of Differential Item Functioning Using a Mixture Item Response Theory Model  

ERIC Educational Resources Information Center

|Usually, methods for detection of differential item functioning (DIF) compare the functioning of items across manifest groups. However, the manifest groups with respect to which the items function differentially may not necessarily coincide with the true source of the bias. It is expected that DIF detection under a model that includes a latent…

Maij-de Meij, Annette M.; Kelderman, Henk; van der Flier, Henk

2010-01-01

152

Improvement in Detection of Differential Item Functioning Using a Mixture Item Response Theory Model  

Microsoft Academic Search

Usually, methods for detection of differential item functioning (DIF) compare the functioning of items across manifest groups. However, the manifest groups with respect to which the items function differentially may not necessarily coincide with the true source of the bias. It is expected that DIF detection under a model that includes a latent DIF variable is more sensitive to this

Annette M. Maij-de Meij; Henk Kelderman; Henk van der Flier

2010-01-01

153

Human NK Cell Subset Functions Are Differentially Affected by Adipokines  

PubMed Central

Background Obesity is a risk factor for various types of infectious diseases and cancer. The increase in adipose tissue causes alterations in both adipogenesis and the production of adipocyte-secreted proteins (adipokines). Since natural killer (NK) cells are the host’s primary defense against virus-infected and tumor cells, we investigated how adipocyte-conditioned medium (ACM) affects functions of two distinct human NK cell subsets. Methods Isolated human peripheral blood mononuclear cells (PBMCs) were cultured with various concentrations of human and murine ACM harvested on two different days during adipogenesis and analyzed by fluorescent-activated cell sorting (FACS). Results FACS analyses showed that the expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), granzyme A (GzmA) and interferon (IFN)-? in NK cells was regulated in a subset-specific manner. ACM treatment altered IFN-? expression in CD56dim NK cells. The production of GzmA in CD56bright NK cells was differentially affected by the distinct adipokine compositions harvested at different states of adipogenesis. Comparison of the treatment with either human or murine ACM revealed that adipokine-induced effects on NK cell expression of the leptin receptor (Ob-R), TRAIL and IFN-? were species-specific. Conclusion Considering the growing prevalence of obesity and the various disorders related to it, the present study provides further insights into the roles human NK cell subsets play in the obesity-associated state of chronic low-grade inflammation.

Huebner, Lena; Engeli, Stefan; Wrann, Christiane D.; Goudeva, Lilia; Laue, Tobias; Kielstein, Heike

2013-01-01

154

Non-differentiable functionals and applications to elliptic problems with discontinuous nonlinearities  

Microsoft Academic Search

Multiple critical points theorems for non-differentiable functionals are established. Applications both to elliptic variational–hemivariational inequalities and eigenvalue problems with discontinuous nonlinearities are then presented.

Gabriele Bonanno; Pasquale Candito

2008-01-01

155

21 CFR 884.6120 - Assisted reproduction accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Assisted reproduction accessories. 884.6120...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a)...

2010-04-01

156

21 CFR 884.6120 - Assisted reproduction accessories.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 false Assisted reproduction accessories. 884.6120...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a)...

2009-04-01

157

19 CFR 10.456 - Accessories, spare parts or tools.  

Code of Federal Regulations, 2013 CFR

...HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Chile Free Trade Agreement Rules of Origin § 10.456 Accessories, spare parts or tools. Accessories, spare parts...

2013-04-01

158

21 CFR 878.3925 - Plastic surgery kit and accessories.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Plastic surgery kit and accessories. 878.3925 ...MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3925 Plastic surgery kit and accessories. (a)...

2009-04-01

159

21 CFR 878.3925 - Plastic surgery kit and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Plastic surgery kit and accessories. 878.3925 ...MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3925 Plastic surgery kit and accessories. (a)...

2010-04-01

160

21 CFR 884.6120 - Assisted reproduction accessories.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Assisted reproduction accessories. 884.6120 Section...OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a)...

2013-04-01

161

21 CFR 884.5350 - Contraceptive diaphragm and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Contraceptive diaphragm and accessories. 884...Therapeutic Devices § 884.5350 Contraceptive diaphragm and accessories. (a) Identification. A contraceptive diaphragm is a closely...

2010-04-01

162

21 CFR 884.5350 - Contraceptive diaphragm and accessories.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Contraceptive diaphragm and accessories. 884...Therapeutic Devices § 884.5350 Contraceptive diaphragm and accessories. (a) Identification. A contraceptive diaphragm is a closely...

2009-04-01

163

21 CFR 884.5350 - Contraceptive diaphragm and accessories.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Contraceptive diaphragm and accessories. 884...Therapeutic Devices § 884.5350 Contraceptive diaphragm and accessories. (a) Identification. A contraceptive diaphragm is a closely...

2013-04-01

164

21 CFR 890.3025 - Prosthetic and orthotic accessory.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Prosthetic and orthotic accessory. 890.3025 Section...PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025 Prosthetic and orthotic accessory. (a)...

2010-04-01

165

21 CFR 890.3025 - Prosthetic and orthotic accessory.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 2013-04-01 false Prosthetic and orthotic accessory. 890.3025 Section...PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025 Prosthetic and orthotic accessory. (a)...

2013-04-01

166

21 CFR 890.3025 - Prosthetic and orthotic accessory.  

Code of Federal Regulations, 2010 CFR

... 2009-04-01 2009-04-01 false Prosthetic and orthotic accessory. 890.3025 Section...PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025 Prosthetic and orthotic accessory. (a)...

2009-04-01

167

21 CFR 884.2960 - Obstetric ultrasonic transducer and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Obstetric ultrasonic transducer and accessories. 884...Devices § 884.2960 Obstetric ultrasonic transducer and accessories. (a) Identification. An obstetric ultrasonic transducer is a device used to...

2010-04-01

168

21 CFR 884.2660 - Fetal ultrasonic monitor and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Fetal ultrasonic monitor and accessories. 884...Monitoring Devices § 884.2660 Fetal ultrasonic monitor and accessories. (a) Identification. A fetal ultrasonic monitor is a device designed to...

2010-04-01

169

21 CFR 884.2960 - Obstetric ultrasonic transducer and accessories.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 false Obstetric ultrasonic transducer and accessories. 884...Devices § 884.2960 Obstetric ultrasonic transducer and accessories. (a) Identification. An obstetric ultrasonic transducer is a device used to...

2009-04-01

170

21 CFR 884.2660 - Fetal ultrasonic monitor and accessories.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Fetal ultrasonic monitor and accessories. 884...Monitoring Devices § 884.2660 Fetal ultrasonic monitor and accessories. (a) Identification. A fetal ultrasonic monitor is a device designed to...

2009-04-01

171

21 CFR 872.6010 - Abrasive device and accessories.  

Code of Federal Regulations, 2013 CFR

...accessories. (a) Identification. An abrasive device and accessories is a device constructed of various abrasives, such as diamond chips, that are glued to shellac-based paper. The device is intended to remove excessive restorative materials,...

2013-04-01

172

21 CFR 872.6250 - Dental chair and accessories.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 false Dental chair and accessories. 872...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6250 Dental chair and accessories....

2013-04-01

173

21 CFR 878.3925 - Plastic surgery kit and accessories.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Plastic surgery kit and accessories. 878...CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3925 Plastic surgery kit and accessories....

2013-04-01

174

The Relationships Between Motivations of Intergroup Differentiation as a Function of Different Dimensions of Social Identity  

Microsoft Academic Search

This article aims to classify social identity-based theories of intergroup differentiation in terms of different dimensions of social identity to understand further the motivational bases of intergroup differentiation. For this purpose, I attempt to incorporate three lines of research in social psychology: (a) theories examining intergroup differentiation as a function of social identity, namely social identity theory and SCT; (b)

Nagihan Ta?demir

2011-01-01

175

Murine Osteoclast Formation and Function: Differential Regulation by Humoral Agents  

Microsoft Academic Search

Although much has been learned recently of the mechanisms that regulate osteoclastic differentiation, much less is known of the means through which their resorptive activity is con- trolled. We have developed an assay that allows us to measure resorptive activity while minimizing the confounding effects of the test agent on differentiation. In this assay, murine os- teoclasts were harvested from

Karen Fuller; Barrie Kirstein; Timothy J. Chambers

2005-01-01

176

Bilateral spinal accessory nerve palsy after rhytidectomy  

Microsoft Academic Search

A 64-year-old patient experienced palsy of the right spinal accessory nerve after rhytidectomy. She was evaluated 6 months after surgery for unexplained shoulder pain and weakness since the procedure. Electrophysiological testing showed bilateral spinal nerve palsy without abnormalities in the other shoulder nerves. The electrophysiological findings supported entrapment as the mechanism, rather than nerve section or pure axonal disease due to

Paul Seror; Henri Lellouche

2006-01-01

177

Controlled Speed Accessory Drive Demonstration Program.  

National Technical Information Service (NTIS)

One phase of the US Department of Energy's (DOE) effort to improve the fuel economy of passenger cars has been the investigation of a Controlled Speed Accessory Drive (CSAD) System. The objective of this specific program, initiated by DOE in association w...

F. W. Hoehn

1981-01-01

178

21 CFR 878.4960 - Operating tables and accessories and operating chairs and accessories.  

Code of Federal Regulations, 2013 CFR

... MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4960 Operating tables and accessories...components, intended for use during diagnostic examinations or surgical procedures to support and position a patient. (b)...

2013-04-01

179

21 CFR 878.4950 - Manual operating table and accessories and manual operating chair and accessories.  

Code of Federal Regulations, 2013 CFR

... MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4950 Manual operating table and accessories...used to support a patient during diagnostic examinations or surgical procedures. (b) Classification. Class I...

2013-04-01

180

Detection of accessory spleens with indium 111-labeled autologous platelets  

SciTech Connect

In two patients with recurrent immune thrombocytopenia, accessory splenic tissue was demonstrated by radionuclide imaging following administration of indium 111-labeled autologous platelets. In one of these patients, no accessory splenic tissue was seen on images obtained with technetium 99m sulfur colloid. This new technique provides a simple means for demonstrating accessory spleens and simultaneously evaluating the life-span of autologous platelets.

Davis, H.H., II; Varki, A.; Heaton, W.A.; Siegel, B.A.

1980-01-01

181

Accessories to the crime: Recent advances in HIV accessory protein biology  

Microsoft Academic Search

Recent advances in understanding the roles of the lentiviral accessory proteins have provided fascinating insight into the\\u000a molecular biology of the virus and uncovered previously unappreciated innate immune mechanisms by which the host defends itself.\\u000a HIV-1 and other lentiviruses have developed accessory proteins that counterattack the antiviral defenses in a sort of evolutionary\\u000a battle. The virus is remarkably adept at

Thomas Gramberg; Nicole Sunseri; Nathaniel R. Landau

2009-01-01

182

Carcinoma origin dictates differential skewing of monocyte function  

PubMed Central

Macrophages are versatile cells, which phenotype is profoundly influenced by their environment. Pro-inflammatory classically activated or M1 macrophages, and anti-inflammatory alternatively-activated or M2 macrophages represent two extremes of a continuum of functional states. Consequently, macrophages that are present in tumors can exert tumor-promoting and tumor-suppressing activity, depending on the tumor milieu. In this study we investigated how human monocytes—the precursors of macrophages—are influenced by carcinoma cells of different origin. We demonstrate that monocytes, stimulated with breast cancer supernatant, showed increased expression of interleukin (IL)-10, IL-8 and chemokines CCL17 and CCL22, which are associated with an alternatively-activated phenotype. By contrast, monocytes that were cultured in supernatants of colon cancer cells produced more pro-inflammatory cytokines (e.g., IL-12 and TNF?) and reactive oxygen species. Secretome analysis revealed differential secretion of proteins by colon and breast cancer cell lines, of which the proteoglycan versican was exclusively secreted by colon carcinoma cell lines. Reducing active versican by blocking with monoclonal antibodies or shRNA diminished pro-inflammatory cytokine production by monocytes. Thus, colon carcinoma cells polarize monocytes toward a more classically-activated anti-tumorigenic phenotype, whereas breast carcinomas predispose monocytes toward an alternatively activated phenotype. Interestingly, presence of macrophages in breast or colon carcinomas correlates with poor or good prognosis in patients, respectively. The observed discrepancy in macrophage activation by either colon or breast carcinoma cells may therefore explain the dichotomy between patient prognosis and macrophage presence in these different tumors. Designing new therapies, directing development of monocytes toward M1 activated tumor macrophages in cancer patients, may have great clinical benefits.

Bogels, Marijn; Braster, Rens; Nijland, Philip G.; Gul, Nuray; van de Luijtgaarden, Wendy; Fijneman, Remond J.A.; Meijer, Gerrit A.; Jimenez, Connie R.; Beelen, Robert H.J.; van Egmond, Marjolein

2012-01-01

183

A Comparison of Function-Based Differential Reinforcement Interventions for Children Engaging in Disruptive Classroom Behavior  

Microsoft Academic Search

This study provides a direct comparison of differential reinforcement of other behavior (DRO) and differential reinforcement\\u000a of alternative behavior (DRA). Participants included three children in center-based classrooms referred for functional assessments\\u000a due to disruptive classroom behavior. Functional assessments included interviews and brief functional analyses. An alternating\\u000a treatments design was used to evaluate the relative effectiveness of function-based DRO and DRA

Matthew W. LeGrayBrad; Brad A. Dufrene; Heather Sterling-Turner; D. Joe Olmi; Katherine Bellone

2010-01-01

184

A Comparison of Function-Based Differential Reinforcement Interventions for Children Engaging in Disruptive Classroom Behavior  

ERIC Educational Resources Information Center

|This study provides a direct comparison of differential reinforcement of other behavior (DRO) and differential reinforcement of alternative behavior (DRA). Participants included three children in center-based classrooms referred for functional assessments due to disruptive classroom behavior. Functional assessments included interviews and brief…

LeGray, Matthew W.; Dufrene, Brad A.; Sterling-Turner, Heather; Olmi, D. Joe; Bellone, Katherine

2010-01-01

185

A Nested Logit Approach for Investigating Distractors as Causes of Differential Item Functioning  

ERIC Educational Resources Information Center

In multiple-choice items, differential item functioning (DIF) in the correct response may or may not be caused by differentially functioning distractors. Identifying distractors as causes of DIF can provide valuable information for potential item revision or the design of new test items. In this paper, we examine a two-step approach based on…

Suh, Youngsuk; Bolt, Daniel M.

2011-01-01

186

The MIMIC Model as a Tool for Differential Bundle Functioning Detection  

ERIC Educational Resources Information Center

Increasingly, researchers interested in identifying potentially biased test items are encouraged to use a confirmatory, rather than exploratory, approach. One such method for confirmatory testing is rooted in differential bundle functioning (DBF), where hypotheses regarding potential differential item functioning (DIF) for sets of items (bundles)…

Finch, W. Holmes

2012-01-01

187

The Impact of Multidimensionality on the Detection of Differential Bundle Functioning Using Simultaneous Item Bias Test  

ERIC Educational Resources Information Center

Douglas, Roussos, and Stout introduced the concept of differential bundle functioning (DBF) for identifying the underlying causes of differential item functioning (DIF). In this study, reference group was simulated to have higher mean ability than the focal group on a nuisance dimension, resulting in DIF for each of the multidimensional items…

Furlow, Carolyn F.; Ross, Terris Raiford; Gagne, Phill

2009-01-01

188

HIV-1 Accessory Protein Vpr: Relevance in the pathogenesis of HIV and potential for therapeutic intervention  

PubMed Central

The HIV protein, Vpr, is a multifunctional accessory protein critical for efficient viral infection of target CD4+ T cells and macrophages. Vpr is incorporated into virions and functions to transport the preintegration complex into the nucleus where the process of viral integration into the host genome is completed. This action is particularly important in macrophages, which as a result of their terminal differentiation and non-proliferative status, would be otherwise more refractory to HIV infection. Vpr has several other critical functions including activation of HIV-1 LTR transcription, cell-cycle arrest due to DCAF-1 binding, and both direct and indirect contributions to T-cell dysfunction. The interactions of Vpr with molecular pathways in the context of macrophages, on the other hand, support accumulation of a persistent reservoir of HIV infection in cells of the myeloid lineage. The role of Vpr in the virus life cycle, as well as its effects on immune cells, appears to play an important role in the immune pathogenesis of AIDS and the development of HIV induced end-organ disease. In view of the pivotal functions of Vpr in virus infection, replication, and persistence of infection, this protein represents an attractive target for therapeutic intervention.

2011-01-01

189

Accessory Oculomotor Nuclei of Man  

Microsoft Academic Search

The interstitial nucleus of Cajal (INC) is an important premotor centre related to the control of eye and head movements. The aim of the present research was to draw a detailed picture of the cytoarchitecture of the human INC, in particular taking into consideration the morphological features of the neurons and their functional implications. Within the neuronal population, two groups

R. Bianchi; M. Gioia

1991-01-01

190

Estrogen receptor accessory proteins: effects on receptor-DNA interactions.  

PubMed Central

Despite a wealth of information about the structure and composition of steroid receptors and their functional domains, little is known about the role of accessory proteins as mediators of receptor activity. To better define the role of such proteins in estrogen receptor (ER) function, we have used immunoaffinity, steroid affinity, and site-specific DNA-affinity chromatography to identify and characterize proteins that associate with human ER (hER) in extracts from MCF-7 cells and hER-expressing CHO (CHO-ER) cells. In addition to the expected 66-kDa hER, a 70-kDa protein was obtained and subsequently identified as a member of the heat shock protein family (hsp70). A 55-kDa protein, detected by all three approaches, was identified as a member of the protein disulfide isomerase family (PDI). Two proteins that were preferentially retained by an ER-specific DNA affinity column (p48 and p45) remain unidentified. Maximal interaction of purified hER with the vitellogenin A2 estrogen response element (ERE) occurred in the presence of all four associated proteins isolated by DNA-affinity chromatography. The increased stability of this complex was due primarily to an increase in the association rate of hER with ERE. Thus, accessory proteins may be required for optimal interaction of ER with EREs.

Landel, C C; Kushner, P J; Greene, G L

1995-01-01

191

Hyperbolic deformation of the strip-equation and the accessory parameters for the torus  

NASA Astrophysics Data System (ADS)

By applying an hyperbolic deformation to the uniformization problem for the infinite strip, we give a method for computing the accessory parameter for the torus with one source as an expansion in the modular parameter q. At O( q 0) we obtain the same equation for the accessory parameter and the same value of the semiclassical action as the one obtained from the b ? 0 limit of the quantum one point function. The procedure can be carried over to the full O( q 2) or even higher order corrections although the procedure becomes somewhat complicated. Here we compute to order q 2 the correction to the weight parameter intervening in the conformal factor and it is shown that the unwanted contribution O( q) to the accessory parameter equation cancel exactly.

Menotti, Pietro

2013-09-01

192

ESF GROUND SUPPORT - MATERIAL DEDICATION ANALYSIS FOR STRUCTURAL STEEL AND ACCESSORIES FROM A COMMERCIAL GRADE SOURCE  

SciTech Connect

The purpose of this analysis is to select the critical characteristics to be verified for steel sets and accessories and the verification methods to be implemented through a material dedication process for the procurement and use of commercial grade structural steel sets and accessories (which have a nuclear safety function) to be used in ground support (with the exception of alcove ground support and alcove opening framing, which are not addressed in this analysis) for the Exploratory Studies Facility (ESF) Topopah Spring (TS) Loop. The ESF TS Loop includes the North Ramp, Main Drift, and South Ramp underground openings.

M.D. Stine

1996-01-23

193

Approximation, integration and differentiation of time functions using a set of orthogonal hybrid functions (HF) and their application to solution of first order differential equations  

Microsoft Academic Search

Differential equations of different types and orders are of utmost importance for mathematical modeling of control system problems. State variable method uses the concept of expressing n number of first order differential equations in vector matrix form to model and analyze\\/synthesize control systems.The present work proposes a new set of orthogonal hybrid functions (HF) which evolved from synthesis of sample-and-hold

Anish Deb; Gautam Sarkar; Anindita Ganguly; Amitava Biswas

194

HYPERDIRE, HYPERgeometric functions DIfferential REduction: MATHEMATICA-based packages for differential reduction of generalized hypergeometric functions pF,F1,F2,F3,F4  

NASA Astrophysics Data System (ADS)

HYPERDIRE is a project devoted to the creation of a set of Mathematica-based programs for the differential reduction of hypergeometric functions. The current version includes two parts: one, pfq, is relevant for manipulations of hypergeometric functions pFp, and the other, AppellF1F4, for manipulations with Appell hypergeometric functions F1,F2,F3,F4 of two variables.

Bytev, Vladimir V.; Yu. Kalmykov, Mikhail; Kniehl, Bernd A.

2013-10-01

195

Redundancy of myostatin and growth\\/differentiation factor 11 function  

Microsoft Academic Search

BACKGROUND: Myostatin (Mstn) and growth\\/differentiation factor 11 (Gdf11) are highly related transforming growth factor ? (TGF?) family members that play important roles in regulating embryonic development and adult tissue homeostasis. Despite their high degree of sequence identity, targeted mutations in these genes result in non-overlapping phenotypes affecting distinct biological processes. Loss of Mstn in mice causes a doubling of skeletal

Alexandra C McPherron; Thanh V Huynh; Se-Jin Lee

2009-01-01

196

Functional skeletal muscle regeneration from differentiating embryonic stem cells  

Microsoft Academic Search

Little progress has been made toward the use of embryonic stem (ES) cells to study and isolate skeletal muscle progenitors. This is due to the paucity of paraxial mesoderm formation during embryoid body (EB) in vitro differentiation and to the lack of reliable identification and isolation criteria for skeletal muscle precursors. Here we show that expression of the transcription factor

Radbod Darabi; Kimberly Gehlbach; Robert M Bachoo; Shwetha Kamath; Mitsujiro Osawa; Kristine E Kamm; Michael Kyba; Rita C R Perlingeiro

2008-01-01

197

Modification of Synapse Formation of Accessory Olfactory Bulb Neurons by Coculture with Vomeronasal Neurons  

Microsoft Academic Search

Previously, a coculture system of accessory olfactory bulb (AOB) neurons and vomeronasal (VN) neurons was established for studying the functional roles of AOB neurons in pheromonal signal processing. In this study, the effect of VN neurons on the development of AOB neurons was examined in a coculture system. Spine density was quantitatively measured for various culture periods of 21, 28,

Yuuki Ishimatsu; Keiko Moriya-Ito; Kazuyo Muramoto; Masumi Ichikawa

2006-01-01

198

Modification of accessory activity of peritoneal cells from Fasciola hepatica infected rats  

Microsoft Academic Search

The effect of Fasciola hepatica excretory—secretory antigen (ESA) was studied in the modulation of the accessory functions of peritoneal cells (PC) of rats infected with the parasite. PC rats infected with F. hepatica 7 and 14 days previously showed a marked decrease in phagocytic activity against Candida tropicalis (P < 0.007 and P < 0.004, respectively). The same effect was

Diana T. Masih; Laura Cervi; Jose M. Casado

1996-01-01

199

Shoulder complaints after neck dissection; is the spinal accessory nerve involved?  

Microsoft Academic Search

The purpose of the current study was to investigate the relation between shoulder morbidity (pain and range of motion), and the function of the spinal accessory nerve after neck dissection. Identifying dysfunction of the nerve gives insight in the mechanisms of post-operative shoulder complaints. In total 112 patients after neck dissection (73 males\\/39 females), mean (SD) age 61 (13) years,

C. P van Wilgen; P. U. Dijkstra; B. F. A. M van der Laan; J. T. Plukker; J. L. N. Roodenburg

2003-01-01

200

Differential recursion relations for Laguerre functions on symmetric cones  

Microsoft Academic Search

Let ? be a symmetric cone and V the corresponding simple Euclidean Jordan algebra. In our previous papers (some with G. Zhang) we considered the family of generalized Laguerre functions on ? that generalize the classical Laguerre functions on R+. This family forms an orthogonal basis for the subspace of L-invariant functions in L2(?,d??), where d?? is a certain measure

Michael Aristidou; Mark Davidson; Gestur Ólafsson

2006-01-01

201

Strenght of MISTY1 without FL Function for Higher Order Differential Attack  

Microsoft Academic Search

The encryption algorithm MISTY is a “provably secure” one against Linear and Differential cryptanalysis. Since the designer\\u000a showed 3 round MISTY1 without FL function is provable secure, we omit FL to estimate the strength for Higher Order Differential\\u000a Attack. This attack is a chosen plain text attack and uses the value of higher order differential of output to derive an

Hidema Tanaka; Kazuyuki Hisamatsu; Toshinobu Kaneko

1999-01-01

202

Exposure to TCDD during development permanently alters reproductive function in male Long Evans rats and hamsters: reduced ejaculated and epididymal sperm numbers and sex accessory gland weights in offspring with normal androgenic status.  

PubMed

Prenatal administration of relatively low doses of TCDD alters reproductive development and fertility of the progeny. Fertility was reduced in the progeny of Wistar rats exposed to 0.5 micrograms TCDD/kg/day from Gestational Day (GD) 6 to GD 15. In a three-generation reproduction study, TCDD reduced fertility of Sprague-Dawley rats in the F1 and F2 but not the F0 (no developmental exposure) generation at 0.01 microgram/kg/day in the diet. Furthermore, administration of TCDD on GD 15 (at 0.064 to 1 microgram/kg) both demasculinized and feminized morphology and behavior of Holtzman male rat offspring. Our objectives were to expand the observations of Mably et al. (1992, Toxicol, Appl. Pharmacol. 114, 97-107, 108-117, 118-126) on the effects of gestational administration of a single dose of TCDD to another strain of rat and another species, the hamster. In the first study, Long Evans (LE) hooded rats were dosed by gavage with 1 microgram TCDD/kg on GD 8 (during the period of major organogenesis) or GD 15 (the gestational day used by Mably et al.). In the second study, pregnant Syrian hamsters, a species relatively insensitive to the lethal effects of TCDD, were dosed on GD 11, equivalent to GD 15 in the rat, with TCDD at 2 micrograms/kg. When LE rats were dosed on GD 15, or when hamsters were dosed on GD 11, puberty (preputial separation) was delayed by about 3 days, ejaculated sperm counts were reduced by at least 58%, and epididymal sperm storage was reduced by 38%. Testicular sperm production was less affected. The sex accessory glands were also reduced in size in LE rat offspring treated on GD 15 despite the fact that serum testosterone (T), T production by the testis in vitro, and androgen receptor (AR) levels were not reduced. Some reproductive measures, such as anogenital distance and male sex behavior, were altered by TCDD treatment in rat but not hamster offspring. Since T and AR levels appeared normal in the sex accessory glands and the epididymis following perinatal TCDD exposure, the alterations in these tissues are not likely to have resulted from an alteration of the androgenic status of the male offspring. PMID:7878665

Gray, L E; Kelce, W R; Monosson, E; Ostby, J S; Birnbaum, L S

1995-03-01

203

Parental Alcoholism and Family Functioning: Effects on Differentiation Levels of Young Adults  

Microsoft Academic Search

This study investigated the impact of parental alcoholism and various indices of family functioning on differentiation levels of young adults. A total of 813 college students completed the Differentiation of Self Inventory (DSI; Skowron & Friedlander, 1998), the Self-Report Family Inventory Version II (SFI; Beavers & Hampson, 1990), and questions related to experiences in their families of origin. Analyses indicated

Patrick Johnson; Rachel Stone

2009-01-01

204

Exploring Differential Bundle Functioning in Mathematics by Gender: The Effect of Hierarchical Modelling  

ERIC Educational Resources Information Center

Researchers interested in exploring substantive group differences are increasingly attending to bundles of items (or testlets): the aim is to understand how gender differences, for instance, are explained by differential performances on different types or bundles of items, hence differential bundle functioning (DBF). Some previous work has…

Ong, Yoke Mooi; Williams, Julian; Lamprianou, Iasonas

2013-01-01

205

Functional gene screening in embryonic stem cells implicates Wnt antagonism in neural differentiation  

Microsoft Academic Search

The multilineage differentiation capacity of mouse embryonic stem (ES) cells offers a potential testing platform for gene products that mediate mammalian lineage determination and cellular specialization. Identification of such differentiation regulators is crucial to harnessing ES cells for pharmaceutical discovery and cell therapy. Here we describe the use of episomal expression technology for functional evaluation of cDNA clones during ES-cell

Jerôme Aubert; Hannah Dunstan; Ian Chambers; Austin Smith

2002-01-01

206

Value Function Computation in Fuzzy Real Options by Differential Evolution  

Microsoft Academic Search

Real options are a typical framework in economics that involves uncertainty. The definition of the value function of real options can take advantage of a model of uncertainty that includes stochastic processes and fuzzy numbers; to perform the complete analysis with American type real options, we need to compute the fuzzy extension of the value function for A special version

Maria Letizia Guerra; Laerte Sorini; Luciano Stefanini

2009-01-01

207

Theory of differential equations in discontinuous piecewise-defined functions  

Microsoft Academic Search

A truly general and systematic theory of finite element methods (FEM) should be formulated using, as trial and test functions, piecewise-defined functions that can be fully discontinuous across the internal boundary, which separates the elements from each other. Some of the most relevant work addressing such formu- lations is contained in the literature on discontinuous Galerkin (dG) methods and on

I. Herrera

2007-01-01

208

Compactly supported solutions of functional-differential equations and their applications  

Microsoft Academic Search

CONTENTS Introduction § 1. The function and its properties § 2. Generalized Taylor series for certain classes of infinitely differentiable functions § 3. Approximation by means of the function § 4. Application of solutions of an FDE with compact support and generalized Taylor series in the theory of FDE's § 5. Generalizations and unsolved problems References

V. A. Rvachev

1990-01-01

209

Compactly supported solutions of functional-differential equations and their applications  

Microsoft Academic Search

CONTENTS Introduction § 1. The function up(x) and its properties § 2. Generalized Taylor series for certain classes of infinitely differentiable functions § 3. Approximation by means of the function up(x) § 4. Application of solutions of an FDE with compact support and generalized Taylor series in the theory of FDE's § 5. Generalizations and unsolved problems References

V. A. Rvachev

1990-01-01

210

Variational Methods and Almost Periodic Solutions of Second Order Functional Differential Equations with Infinite Delay  

Microsoft Academic Search

By means of variational methods, we study the existence and uniqueness of almost\\u000aperiodic solutions for a class of second order neutral functional differential\\u000aequations with infinite delay.

Moez Ayachi

2010-01-01

211

On Minimizing the Sum of Squares of Functional Vector Norms of Differential Operators Under Constraints.  

National Technical Information Service (NTIS)

This paper considers the problem of minimizing the sum of squares of functional vector norms of differential operators under a general class of constraints. Several sufficient conditions are given for the existence of a solution. The minimization problem ...

R. C. Brown A. M. Krall

1976-01-01

212

Variation in Differential and Total Cross Sections Due to Different Radial Wave Functions  

ERIC Educational Resources Information Center

Three sets of analytical wave functions are used to calculate the Na (3s---3p) transition differential and total electron excitation cross sections by Born approximations. Results show expected large variations in values. (Author/CP)

Williamson, W., Jr.; Greene, T.

1976-01-01

213

Existence of positive periodic solutions for functional differential equations with impulse effects on time scales  

NASA Astrophysics Data System (ADS)

By using a fixed point theorem of strict-set-contraction, some criteria are established for the existence of positive periodic solutions for a functional differential equation with delays and impulses on time scales.

Zhang, Hongtao; Li, Yongkun

2009-01-01

214

On the Relationship between Differential Item Functioning and Item Difficulty: An Issue of Methods? Item Response Theory Approach to Differential Item Functioning  

ERIC Educational Resources Information Center

|The relationship between differential item functioning (DIF) and item difficulty on the SAT is such that more difficult items tended to exhibit DIF in favor of the focal group (usually minority groups). These results were reported by Kulick and Hu, and Freedle and have been enthusiastically discussed by more recent literature. Examining the…

Santelices, Maria Veronica; Wilson, Mark

2012-01-01

215

Examining the Effects of Differential Item (Functioning and Differential) Test Functioning on Selection Decisions: When Are Statistically Significant Effects Practically Important?  

Microsoft Academic Search

Item response theory differential test functioning (DTF) methods are often used to address issues in personnel selection, but the results are frequently difficult to interpret because statistically significant findings may have little practical importance. In this article, the authors proposed 2 effect size measures for DTF. One related DTF to mean raw score differences across groups; the other related DTF

Stephen Stark; Oleksandr S. Chernyshenko; Fritz Drasgow

2004-01-01

216

Differential Effects of Executive Functioning on Suicide Attempts  

PubMed Central

Suicide is common among individuals with psychiatric illness; executive functioning may be associated with suicide risk. The authors examined demographic, clinical, and executive-functioning variables in suicide ideators and suicide attempters, hypothesizing that attempters would demonstrate poorer executive-functioning skills. Seventy-seven participants with psychiatric illness completed a neuropsychological battery while hospitalized or residing in crisis-houses after expressing suicidal ideation (N=40) or making a suicide attempt (N=37). Logistic regression predicted suicide Ideator versus suicide Attempter status; suicide Attempters exhibited poorer inhibition but better problem-solving ability than suicide Ideators. Suicide attempt risk may be associated with better problem-solving skills, but worse inhibitory control.

Burton, Cynthia Z.; Vella, Lea; Weller, Jennifer A.; Twamley, Elizabeth W.

2013-01-01

217

A Unique Case of Intradural Communicating Branches between the Accessory Nerve and the Dorsal Roots of the Cervical Spinal Nerves.  

PubMed

Objective The accessory nerve has cranial and spinal roots. The cranial roots emerge from the medulla, whereas the spinal roots arise from motor cells within the ventral horn of C1-C7 segments of the spinal cord. Communications have been described between the spinal accessory nerve rootlets and the dorsal rootlets of cervical spinal nerves. In the present case, we report a communication that has not been reported before and discuss the functional anatomy.Materials and Methods During the dissection of the craniovertebral junction of a 67-year-old formalin-fixed adult male cadaver, a connection between the spinal accessory nerve rootlets and the dorsal rootlets of the cervical spinal nerves was observed.Results A communication between the spinal rootlets of the accessory nerve and the dorsal roots of cervical spinal nerves was present on the right and left side. On the right, a communication between the accessory nerve spinal rootlet and the dorsal rootlet of the fourth cervical spinal nerve existed. On the left, there were two branches from the lowest accessory nerve spinal rootlet, one run ventrally and the other dorsally to the spinal rootlet and reached the dorsal root of third cervical spinal nerve. The dorsal root of C1 did not exist on either the right or the left side. Further, an unusual spinal accessory nerve formation was also observed.Discussion This case does not fit into any of the previously described classifications in the literature. Therefore, the different variations concerning the communications between the spinal rootlets of the accessory nerve and the cervical spinal nerves should be kept in mind during both surgical, especially radical neck dissections, and nonsurgical evaluations. PMID:23397124

Seker, A?k?n; Ceylan, Davut; Tatarl?, Necati; Abdullaev, Tuychiboy; Gülbar, Seda; Konya, Deniz; Bayri, Yasar; Kele?, Evren; K?l?ç, Türker; Cavdar, Safiye

2013-02-08

218

MULTIPLE SOLUTIONS FOR NONRESONANCE IMPULSIVE FUNCTIONAL DIFFERENTIAL EQUATIONS  

Microsoft Academic Search

In this paper we investigate the existence of multiple solutions for first and second order impulsive functional dierential equations with bound- ary conditions. Our main tool is the Leggett and Williams fixed point theorem.

MOUFFAK BENCHOHRA; ABDELGHANI OUAHAB

2003-01-01

219

IMPULSIVE NEUTRAL FUNCTIONAL DIFFERENTIAL INCLUSIONS WITH VARIABLE TIMES  

Microsoft Academic Search

In this paper, we study the existence of solutions for first and second order impulsive neutral functional dierential inclusions with variable times. Our main tool is a fixed point theorem due to Martelli for condensing multivalued maps.

MOUFFAK BENCHOHRA; ABDELGHANI OUAHAB

2003-01-01

220

21 CFR 870.4200 - Cardiopulmonary bypass accessory equipment.  

Code of Federal Regulations, 2013 CFR

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Surgical Devices § 870.4200 Cardiopulmonary bypass accessory equipment. (a) Identification. Cardiopulmonary...

2013-04-01

221

Relationships among hemocytes, tunic cells, germ cells, and accessory cells in the colonial ascidian Botryllus schlosseri.  

PubMed

Monoclonal antibodies were raised against hemocytes of the colonial ascidian Botryllus schlosseri as possible tools to study hemocyte differentiation. In this species, blood cells are involved in various biological functions, such as immunosurveillance, encapsulation of foreign bodies, metal accumulation, and allorecognition. The latter process drives the fusion or rejection of contacting colonies, according to whether they do or do not share at least one allele at the fusibility/histocompatibility (Fu/HC) locus. Hemocytes take part in the rejection reaction, which suggests that they express molecules, coded by the Fu/HC locus, on their surface. A homozygous colony at the Fu/HC locus was used to produce the antibodies, which were screened by immunocytochemistry on hemocyte monolayers, immunohistochemistry on colony paraffin sections, and immunoblotting on colony homogenates. Here, we report on one of the obtained antibodies (1D8), which recognized a surface epitope on hemocytes of the donor colony and other colonies, apparently in a manner specific to the Fu/HC genotype. It also labeled a single 80-kDa band in colony homogenates. In addition, it specifically recognized tunic cells, germ cells, and their accessory cells. These results strengthen the assumption of a close relationship among these types of cells and blood cells, and suggest a close relationship among the above cells, probably deriving from undifferentiated blood cells. PMID:21246708

Ballarin, Loriano; Del Favero, Marcello; Manni, Lucia

2011-01-18

222

Transcriptional activation of melanocortin 2 receptor accessory protein by PPAR? in adipocytes.  

PubMed

Adrenocorticotropic hormone (ACTH) in rodents decreases lipid accumulation and body weight. Melanocortin receptor 2 (MC2R) and MC2R accessory protein (MRAP) are specific receptors for ACTH in adipocytes. Peroxisome proliferator-activated receptor ? (PPAR?) plays a role in the transcriptional regulation of metabolic pathways such as adipogenesis and ?-oxidation of fatty acids. In this study we investigated the transcriptional regulation of MRAP expression during differentiation of 3T3-L1 cells. Stimulation with ACTH affected lipolysis in murine mature adipocytes via MRAP. Putative peroxisome proliferator response element (PPRE) was identified in the MRAP promoter region. In chromatin immunoprecipitation and reporter assays, we observed binding of PPAR? to the MRAP promoter. The mutagenesis experiments showed that the -1209/-1198 region of the MRAP promoter could function as a PPRE site. These results suggest that PPAR? is required for transcriptional activation of the MRAP gene during adipogenesis, which contributes to understanding of the molecular mechanism of lipolysis in adipocytes. PMID:23994134

Kim, Nam Soo; Kim, Yoon-Jin; Cho, Si Young; Lee, Tae Ryong; Kim, Sang Hoon

2013-08-28

223

Chondrocytic Atf4 regulates osteoblast differentiation and function via Ihh  

PubMed Central

Atf4 is a leucine zipper-containing transcription factor that activates osteocalcin (Ocn) in osteoblasts and indian hedgehog (Ihh) in chondrocytes. The relative contribution of Atf4 in chondrocytes and osteoblasts to the regulation of skeletal development and bone formation is poorly understood. Investigations of the Atf4–/–;Col2a1-Atf4 mouse model, in which Atf4 is selectively overexpressed in chondrocytes in an Atf4-null background, demonstrate that chondrocyte-derived Atf4 regulates osteogenesis during development and bone remodeling postnatally. Atf4 overexpression in chondrocytes of the Atf4–/–;Col2a1-Atf4 double mutants corrects the reduction in stature and limb in Atf4–/– embryos and rectifies the decrease in Ihh expression, Hh signaling, proliferation and accelerated hypertrophy that characterize the Atf4–/– developing growth plate cartilages. Unexpectedly, this genetic manipulation also restores the expression of osteoblastic marker genes, namely Ocn and bone sialoprotein, in Atf4–/– developing bones. In Atf4–/–;Col2a1-Atf4 adult mice, all the defective bone parameters found in Atf4–/– mice, including bone volume, trabecular number and thickness, and bone formation rate, are rescued. In addition, the conditioned media of ex vivo cultures from wild-type or Atf4–/–;Col2a1-Atf4, but not Atf4–/– cartilage, corrects the differentiation defects of Atf4–/– bone marrow stromal cells and Ihh-blocking antibody eliminates this effect. Together, these data indicate that Atf4 in chondrocytes is required for normal Ihh expression and for its paracrine effect on osteoblast differentiation. Therefore, the cell-autonomous role of Atf4 in chondrocytes dominates the role of Atf4 in osteoblasts during development for the control of early osteogenesis and skeletal growth.

Wang, Weiguang; Lian, Na; Ma, Yun; Li, Lingzhen; Gallant, Richard C.; Elefteriou, Florent; Yang, Xiangli

2012-01-01

224

Insights learned from pBTAi1, a 229-kb accessory plasmid from Bradyrhizobium sp. strain BTAi1 and prevalence of accessory plasmids in other Bradyrhizobium sp. strains  

Microsoft Academic Search

In silico, physiological and in planta analyses were used to characterize pBTAi1, a 229-kb accessory plasmid from Bradyrhizobium sp. strain BTAi1, and assess its potential ecological function under free-living and symbiotic growth conditions. Sequence analysis revealed the presence of an uptake hydrogenase system, a repABC family plasmid replication module and open reading frames encoding type IV secretion system, TraI and

Eddie J Cytryn; Siriluck Jitacksorn; Eric Giraud; Michael J Sadowsky

2008-01-01

225

Functional integro-differential stochastic evolution equations in Hilbert space  

Microsoft Academic Search

We investigate a class of abstract functional integro-dierential stochastic evolution equa- tions in a real separable Hilbert space. Global existence results concerning mild and pe- riodic solutions are formulated under various growth and compactness conditions. Also, related convergence results are established and an example,arising in the mathematical modeling of heat conduction is discussed to illustrate the abstract theory. Key words:

David N. Keck; Mark A. McKibben

2003-01-01

226

Relating Neuronal Firing Patterns to Functional Differentiation of Cerebral Cortex  

PubMed Central

It has been empirically established that the cerebral cortical areas defined by Brodmann one hundred years ago solely on the basis of cellular organization are closely correlated to their function, such as sensation, association, and motion. Cytoarchitectonically distinct cortical areas have different densities and types of neurons. Thus, signaling patterns may also vary among cytoarchitectonically unique cortical areas. To examine how neuronal signaling patterns are related to innate cortical functions, we detected intrinsic features of cortical firing by devising a metric that efficiently isolates non-Poisson irregular characteristics, independent of spike rate fluctuations that are caused extrinsically by ever-changing behavioral conditions. Using the new metric, we analyzed spike trains from over 1,000 neurons in 15 cortical areas sampled by eight independent neurophysiological laboratories. Analysis of firing-pattern dissimilarities across cortical areas revealed a gradient of firing regularity that corresponded closely to the functional category of the cortical area; neuronal spiking patterns are regular in motor areas, random in the visual areas, and bursty in the prefrontal area. Thus, signaling patterns may play an important role in function-specific cerebral cortical computation.

Matsuno, Nanae; Funahashi, Shintaro; Shima, Keisetsu; Fujita, Ichiro; Tamura, Hiroshi; Doi, Taijiro; Kawano, Kenji; Inaba, Naoko; Fukushima, Kikuro; Kurkin, Sergei; Kurata, Kiyoshi; Taira, Masato; Tsutsui, Ken-Ichiro; Komatsu, Hidehiko; Ogawa, Tadashi; Koida, Kowa; Tanji, Jun; Toyama, Keisuke

2009-01-01

227

Differentiating High-Functioning Autism and Social Phobia  

ERIC Educational Resources Information Center

|Both high-functioning autism (HFA) and social phobia (SP) involve profound social interaction deficits. Although these disorders share some similar symptoms, they are conceptualized as distinct. Because both HFA and SP are defined behaviorally, the degree of overlap between the two disorders may result in misinterpretation of symptoms. However,…

Tyson, Katherine E.; Cruess, Dean G.

2012-01-01

228

Numerical solution of differential equations using multiquadric radial basis function networks  

Microsoft Academic Search

This paper presents mesh-free procedures for solving linear differential equations (ODEs and elliptic PDEs) based on multiquadric (MQ) radial basis function networks (RBFNs). Based on our study of approximation of function and its derivatives using RBFNs that was reported in an earlier paper (Mai-Duy, N. & Tran-Cong, T. (1999). Approximation of function and its derivatives using radial basis function networks.

Nam Mai-duy; Thanh Tran-cong

2001-01-01

229

Phenotypic and functional characteristics of mesenchymal stem cells differentiated along a Schwann cell lineage.  

PubMed

We have investigated the phenotypic and bioassay characteristics of bone marrow mesenchymal stromal cells (MSCs) differentiated along a Schwann cell lineage using glial growth factor. Expression of the Schwann cell markers S100, P75, and GFAP was determined by immunocytochemical staining and Western blotting. The levels of the stem cell markers Stro-1 and alkaline phosphatase and the neural progenitor marker nestin were also examined throughout the differentiation process. The phenotypic properties of cells differentiated at different passages were also compared. In addition to a phenotypic characterization, the functional ability of differentiated MSCs has been investigated employing a co-culture bioassay with dissociated primary sensory neurons. Following differentiation, MSCs underwent morphological changes similar to those of cultured Schwann cells and stained positively for all three Schwann cell markers. Quantitative Western blot analysis showed that the levels of S100 and P75 protein were significantly elevated upon differentiation. Differentiated MSCs were also found to enhance neurite outgrowth in co-culture with sensory neurons to a level equivalent or superior to that produced by Schwann cells. These findings support the assertion that MSCs can be differentiated into cells that are Schwann cell-like in terms of both phenotype and function. PMID:16977603

Caddick, Jenny; Kingham, Paul J; Gardiner, Natalie J; Wiberg, Mikael; Terenghi, Giorgio

2006-12-01

230

MLH1 mutations differentially affect meiotic functions in Saccharomyces cerevisiae.  

PubMed Central

To test whether missense mutations in the cancer susceptibility gene MLH1 adversely affect meiosis, we examined 14 yeast MLH1 mutations for effects on meiotic DNA transactions and gamete viability in the yeast Saccharomyces cerevisiae. Mutations analogous to those associated with hereditary nonpolyposis colorectal cancer (HNPCC) or those that reduce Mlh1p interactions with ATP or DNA all impair replicative mismatch repair as measured by increased mutation rates. However, their effects on meiotic heteroduplex repair, crossing over, chromosome segregation, and gametogenesis vary from complete loss of meiotic functions to no meiotic defect, and mutants defective in one meiotic process are not necessarily defective in others. DNA binding and ATP binding but not ATP hydrolysis are required for meiotic crossing over. The results reveal clear separation of different Mlh1p functions in mitosis and meiosis, and they suggest that some, but not all, MLH1 mutations may be a source of human infertility.

Hoffmann, Eva R; Shcherbakova, Polina V; Kunkel, Thomas A; Borts, Rhona H

2003-01-01

231

In vitro models of differentiated sertoli cell structure and function  

Microsoft Academic Search

Summary  Primary cultures of Sertoli cells maintained in conventional cultures on plastic culture vessels do not retain many of the\\u000a structural and functional properties of their in vivo counterparts. Sertoli cell phenotype is better maintained by incorporating\\u000a certain environmental parameters, intrinsic to the testic, into the Sertoli cell culture system. These environmental parameters\\u000a include a) high cell density, b) a unique

Mark A. Hadley; Stephen W. Byers; Carlos A. Suárez-Quian; daniel Djakiew; Martin Dym

1988-01-01

232

Differential subcellular localization of functionally divergent survivin splice variants  

Microsoft Academic Search

Survivin is an inhibitor of apoptosis protein (IAP) that is markedly overexpressed in most cancers. We identified two novel functionally divergent splice variants, i.e. non-antiapoptotic survivin-2B and antiapoptotic survivin-?Ex3. Because survivin-2B might be a naturally occurring antagonist of antiapoptotic survivin variants, we analyzed the subcellular distribution of these proteins. PSORT II analysis predicted a preferential cytoplasmic localization of survivin and

C Mahotka; J Liebmann; M Wenzel; C V Suschek; M Schmitt; H E Gabbert; C D Gerharz

2002-01-01

233

Solving Partial Differential Equations by Collocation with Radial Basis Functions  

Microsoft Academic Search

. Motivated by [5] we describe a method related to scatteredHermite interpolation for which the solution of elliptic partial differentialequations by collocation is well-posed. We compare the method of [5] withour method.x1. IntroductionIn this paper we discuss the numerical solution of elliptic partial differentialequations using a collocation approach based on radial basis functions. Tomake the discussion transparent we will focus

Gregory E. Fasshauer

1997-01-01

234

Differential functions of ras for malignant phenotypic conversion  

Microsoft Academic Search

Among the effector molecules connected with the group of cell surface receptors, Ras proteins have essential roles in transducing\\u000a extracellular signals to diverse intracellular events, by controlling the activities of multiple signaling pathways. For over\\u000a 20 years since the discovery of Ras proteins, an enormous amount of knowledge has been accumulated as to how the proteins\\u000a function in overlapping or

Aree Moon

2006-01-01

235

Theory of multipliers in spaces of differentiable functions  

NASA Astrophysics Data System (ADS)

CONTENTS Introduction Chapter I. Embedding theorems for Sobolev spaces § 1.1. The summability with respect to a measure of functions from the spaces W_p^m and w_p^m, p > 1 § 1.2. The summability with respect to a measure of functions from the spaces W_1^m and w_1^m Chapter II. Multipliers in pairs of Sobolev spaces § 2.1. A description of the spaces M(W_p^m\\to W_p^l) and M(w_p^m\\to w_p^l) § 2.2. The space M(W_p^m\\to W_p^l) § 2.3. The space M(W_p^m\\to W_p^{-k}) Chapter III. A survey of other results about spaces of multipliers § 3.1. Multipliers in pairs of spaces of Bessel potentials § 3.2. Multipliers in pairs of Slobodetskii spaces § 3.3. Some properties of multipliers § 3.4. Multipliers in pairs of Sobolev spaces in a domain § 3.5. Multipliers on the space BMO § 3.6. Multipliers on certain spaces of analytic functions § 3.7. Applications of multipliers References

Maz'ya, V. G.; Shaposhnikova, T. O.

1983-06-01

236

TSH receptor function is required for normal thyroid differentiation in zebrafish.  

PubMed

TSH is the primary physiological regulator of thyroid gland function. The effects of TSH on thyroid cells are mediated via activation of its membrane receptor [TSH receptor (TSHR)]. In this study, we examined functional thyroid differentiation in zebrafish and characterized the role of TSHR signaling during thyroid organogenesis. Cloning of a cDNA encoding zebrafish Tshr showed conservation of primary structure and functional properties between zebrafish and mammalian TSHR. In situ hybridization confirmed that the thyroid is the major site of tshr expression during zebrafish development. In addition, we identified tpo, iyd, duox, and duoxa as novel thyroid differentiation markers in zebrafish. Temporal analyses of differentiation marker expression demonstrated the induction of an early thyroid differentiation program along with thyroid budding, followed by a delayed onset of duox and duoxa expression coincident with thyroid hormone synthesis. Furthermore, comparative analyses in mouse and zebrafish revealed for the first time a thyroid-enriched expression of cell death regulators of the B-cell lymphoma 2 family during early thyroid morphogenesis. Knockdown of tshr function by morpholino microinjection into embryos did not affect early thyroid morphogenesis but caused defects in later functional differentiation. The thyroid phenotype observed in tshr morphants at later stages comprised a reduction in number and size of functional follicles, down-regulation of differentiation markers, as well as reduced thyroid transcription factor expression. A comparison of our results with phenotypes observed in mouse models of defective TSHR and cAMP signaling highlights the value of zebrafish as a model to enhance the understanding of functional differentiation in the vertebrate thyroid. PMID:21737742

Opitz, Robert; Maquet, Emilie; Zoenen, Maxime; Dadhich, Rajesh; Costagliola, Sabine

2011-07-07

237

Environmental sensitivity of Ru(II) complexes: the role of the accessory ligands.  

PubMed

A suite of Ru(II) complexes in which one ligand is pH responsive and the other two are varied in an effort to achieve improved photophysics has been synthesized and their potential as pH reporters assessed. The more general purpose of the study was to examine the role of the accessory ligands in heteroleptic reporter complexes and the degree to which such ligands can affect the performance of luminescent reporters. For this suite of complexes, judicious choice of the accessory ligand can alter both the pK(a)* and the dynamic range of response. It was found that the emission color and brightness were influenced by pH, but the lifetimes were only weakly affected. Surprisingly, some accessory ligands which should have improved luminescent properties essentially turned off the pH response. Several possible reasons for this observation are explored. It is suggested, and density functional theory (DFT) calculations support, that the relative ?* levels of the pH sensitive and the accessory ligands are critical. PMID:22394071

Dixon, Eileen N; Snow, Michael Z; Bon, Jennifer L; Whitehurst, Alison M; DeGraff, Benjamin A; Trindle, Carl; Demas, James N

2012-03-06

238

Roles of accessory subunits in alpha4beta2(*) nicotinic receptors.  

PubMed

Accessory subunits in heteromeric nicotinic receptors (AChRs) do not take part in forming ACh binding sites. alpha5 and beta3 subunits can function only as accessory subunits. We show that both alpha5 and beta3 efficiently assemble in human alpha4beta2(*) AChRs expressed in permanently transfected human embryonic kidney (HEK) cell lines. Only (alpha4beta2)(2)alpha5, not (alpha4beta2)(2)beta3 AChRs, have been detected in brain. The alpha4beta2alpha5 line expressed 40% more AChRs than the parent alpha4beta2 line and was equally sensitive to up-regulation by nicotine. The alpha4beta2beta3 line expressed 25-fold more AChRs than the parental line and could not be further up-regulated by nicotine. Relative sensitivity to activation by ACh depends on the accessory subunit, beta2 conferring the greatest sensitivity, alpha5 less, and beta3 and alpha4 much less. Accessory subunits form binding sites for positive allosteric modulators, as illustrated by the observation that alpha5 conferred high sensitivity to galanthamine. In the presence of alpha5 or beta3, stable, partially degraded, dead end intermediates accumulated within the cells. These may have the form alpha5alpha4beta2alpha5. The efficiency with which alpha5 and beta3 assemble with alpha4 and beta2 and the necessity of avoiding formation of potentially toxic intermediates may explain why alpha5 and beta3 seem to be transcribed at low levels in brain. Autosomal dominant nocturnal frontal lobe epilepsy can be caused by the alpha4 mutation S247F. This mutant did not produce functional AChRs unless cells were cotransfected with alpha5, beta3, or alpha6 to replace alpha4 as accessory subunit. PMID:18381563

Kuryatov, Alexandre; Onksen, Jennifer; Lindstrom, Jon

2008-04-01

239

Which pulmonary function tests best differentiate between COPD phenotypes?  

PubMed

We are still at the early phase of finding useful phenotypes in COPD that can guide therapy. However, in a simple sense, "sick patients die." Many phenotypic measurements of severity correlate with mortality in COPD: FEV(1), the ratio of inspiratory capacity to total lung capacity (IC/TLC), diffusing capacity of the lung for carbon monoxide (D(LCO)), 6-min walk distance, and maximum oxygen (O(2)) consumption or maximum watts on exercise testing. However, composite parameters, such as the BODE index (body mass index, air flow obstruction, dyspnea, exercise capacity), perform better, likely because they capture different aspects of severity that affect functional impairment and risk of death. Bronchodilator responsiveness is just a relative feature that aids in distinction of asthma and COPD but is not diagnostic in this use. A normal D(LCO) helps to rule out exercise-induced O(2) desaturation, but those with a low D(LCO) and COPD need exercise measurements to confirm desaturation. Currently, pulmonary function tests (PFTs) alone do not define subsets who respond to particular therapies. The presence of air flow obstruction and its severity increase the risk of lung cancer in COPD patients. Inflammatory biomarkers (exhaled nitric oxide and eosinophilia in sputum or bronchoalveolar lavage fluid) help distinguish asthma from COPD. Genetics is a promising area to elucidate pathophysiology and treatment for asthma and COPD, but currently alpha-1 antitrypsin deficiency is the only genetically-determined phenotype that has relevance for COPD management. The best promise for the future seems to be in composite phenotypes or scores, both for distinguishing asthma from COPD, and for guiding therapeutic options. It may be better to throw out the old, limiting diagnostic concepts. If, instead, we start from outcomes of interest, perhaps we can work back to predictors of these outcomes, and organize new diagnostic entities that have predictive relevance for treatment choices, functional outcomes, and mortality. PMID:22222125

Salzman, Steve H

2012-01-01

240

21 CFR 878.4820 - Surgical instrument motors and accessories/attachments.  

Code of Federal Regulations, 2010 CFR

... false Surgical instrument motors and accessories/attachments...4820 Surgical instrument motors and accessories/attachments...Identification. Surgical instrument motors and accessories are AC-powered...osteotome), dermabrasion brush, dermatome, drill bit,...

2009-04-01

241

49 CFR 178.255-7 - Protection of valves and accessories.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Protection of valves and accessories. 178.255-7 Section 178...Portable Tanks § 178.255-7 Protection of valves and accessories. (a) All valves, fittings, accessories, safety...

2011-10-01

242

Differential changes in retina function with normal aging in humans  

Microsoft Academic Search

We evaluated the full field electroretinogram (ERG) to assess age-related changes in retina function in humans. ERG recordings\\u000a were performed on healthy subjects with normal fundus appearance, lack of cataract and 20\\/20 acuity, aged 20–39 years (n = 27; mean age 25 ± 5, standard deviation), 40–59 years (n = 20; mean 53 ± 5), and 60–82 years (n = 18; mean 69 ± 5). Multiple ERG tests were applied, including light and dark-adapted stimulus-response

Paul R. Freund; Juliane Watson; Gregory S. Gilmour; Frédéric Gaillard; Yves Sauvé

2011-01-01

243

Differential geometry of the Fermat quartic and theta functions  

NASA Astrophysics Data System (ADS)

The universal curve over a finite cover of the moduli space of elliptic curves with level four structure is embedded in C as the Fermat quartic and is parametrized via the four Jacobi theta functions. Constructions from completely integrable systems have shown the importance of looking at the curvature of certain spaces and here we compute sectional curvatures. For our computations, we choose the ambient Fubini-Study metric of C. We also derive several theta identities which arise from the quartic’s holomorphic two-form.

Hadnot, Jason

2012-02-01

244

Minimizing the Real Functions of the ICEC'96 Contest by Differential Evolution  

Microsoft Academic Search

Abstract Differential Evolution (DE) has recently proven to be an efficient method for optimizing real - valued multi - modal objective functions Besides its good convergence properties and suitability for parallelization, DE's main assets are its conceptual simplicity and ease of use This paper describes two variants of DE and summarizes their performance on the real test functions of the

Rainer Storn; Kenneth Price

1996-01-01

245

Analysis of Sources of Latent Class Differential Item Functioning in International Assessments  

ERIC Educational Resources Information Center

|In this study, we investigated differential item functioning (DIF) and its sources using a latent class (LC) modeling approach. Potential sources of LC DIF related to instruction and teacher-related variables were investigated using substantive and three statistical approaches: descriptive discriminant function, multinomial logistic regression,…

Oliveri, Maria Elena; Ercikan, Kadriye; Zumbo, Bruno

2013-01-01

246

A Generalized Logistic Regression Procedure to Detect Differential Item Functioning among Multiple Groups  

ERIC Educational Resources Information Center

|We present an extension of the logistic regression procedure to identify dichotomous differential item functioning (DIF) in the presence of more than two groups of respondents. Starting from the usual framework of a single focal group, we propose a general approach to estimate the item response functions in each group and to test for the presence…

Magis, David; Raiche, Gilles; Beland, Sebastien; Gerard, Paul

2011-01-01

247

Children with High-Functioning Autism and Asperger's Syndrome: Can We Differentiate Their Cognitive Profiles?  

ERIC Educational Resources Information Center

|The aim of this study was to investigate whether children with high-functioning autism (HFA) and Asperger's syndrome (AS) can be differentiated from each other and from typically developing children on their cognitive profiles. The present study included a total of 45 participants: children with autism (high-functioning autism or Asperger's…

Planche, Pascale; Lemonnier, Eric

2012-01-01

248

DIFferential Testlet Functioning Definitions and Detection. Program Statistics Research Technical Report No. 91-9.  

ERIC Educational Resources Information Center

It is sometimes sensible to think of the fundamental unit of test construction as being larger than an individual item. This unit, dubbed the testlet, must pass muster in the same way that items do. One criterion of a good item is the absence of differential item functioning (DIF). The item must function in the same way as all important…

Wainer, Howard; And Others

249

An Investigation of Differential Item Functioning in the MELAB Listening Test  

Microsoft Academic Search

Differential item functioning (DIF) analysis is a way of determining whether test items function differently across subgroups of test takers after controlling for ability level. DIF results are used to evaluate tests' validity arguments. This study uses Rasch measurement to examine the Michigan English Language Assessment Battery listening test for DIF across gender subgroups. After establishing the unidimensionality and local

Vahid Aryadoust; Christine C. M. Goh; Lee Ong Kim

2011-01-01

250

A Generalized Logistic Regression Procedure to Detect Differential Item Functioning Among Multiple Groups  

Microsoft Academic Search

We present an extension of the logistic regression procedure to identify dichotomous differential item functioning (DIF) in the presence of more than two groups of respondents. Starting from the usual framework of a single focal group, we propose a general approach to estimate the item response functions in each group and to test for the presence of uniform DIF, nonuniform

David Magis; Gilles Raîche; Sébastien Béland; Paul Gérard

2011-01-01

251

Differential Item Functioning Analysis of the Mental, Emotional, and Bodily Toughness Inventory  

ERIC Educational Resources Information Center

|In this study the authors used differential item functioning analysis to examine if there were items in the Mental, Emotional, and Bodily Toughness Inventory functioning differently across gender and athletic membership. A total of 444 male (56.3%) and female (43.7%) participants (30.9% athletes and 69.1% non-athletes) responded to the Mental,…

Gao, Yong; Mack, Mick G.; Ragan, Moira A.; Ragan, Brian

2012-01-01

252

DIFferential Testlet Functioning Definitions and Detection. Program Statistics Research Technical Report No. 91-9.  

ERIC Educational Resources Information Center

|It is sometimes sensible to think of the fundamental unit of test construction as being larger than an individual item. This unit, dubbed the testlet, must pass muster in the same way that items do. One criterion of a good item is the absence of differential item functioning (DIF). The item must function in the same way as all important…

Wainer, Howard; And Others

253

New Genes for Male Accessory Gland Proteins in Drosophila melanogaster  

Microsoft Academic Search

The accessory gland of male insects produces components of the seminal fluid that alter the behavior, physiology and life span of the mated female, and contribute to her efficient storage and utilization of sperm. As a step towards understanding how this occurs, we have isolated genes encoding 12 previously unreported accessory gland-specific mRNAs from the fruit fly Drosophila melanogaster. We

Mariana F. Wolfner; Heidi A. Harada; Michael J. Bertram; Thomas J. Stelick; Kevin W. Kraus; John M. Kalb; Y. Oliver Lung; Deborah M. Neubaum; Morgan Park; Uyen Tram

1997-01-01

254

Genes for Male Accessory Gland Proteins in Drosophila Melanogaster.  

National Technical Information Service (NTIS)

The present invention provides a number of accessory gland proteins from Drosophila. The invention also provides an accessory gland protein which is toxic to insect cells and can be used to kill or inhibit the development of insects. Methods of controllin...

K. U. Tram M. F. Wolfner O. Lung

2005-01-01

255

Item and Scale Differential Functioning of the Mini-Mental State Exam Assessed Using the Differential Item and Test Functioning (DFIT) Framework  

PubMed Central

Objectives To illustrate the application of the Differential Item and Test Functioning (DFIT) method using English and Spanish versions of the Mini-Mental State Examination (MMSE). Subjects Study participants were 65 years of age or older and lived in North Manhattan, New York. Of the 1578 study participants who were administered the MMSE 665 completed it in Spanish. Measures The MMSE contains 20 items that measure the degree of cognitive impairment in the areas of orientation, attention and calculation, registration, recall and language, as well as the ability to follow verbal and written commands. Research Design After assessing the dimensionality of the MMSE scale, item response theory person and item parameters were estimated separately for the English and Spanish sample using Samejima’s 2-parameter graded response model. Then the DFIT framework was used to assess differential item functioning (DIF) and differential test functioning (DTF). Results Nine items were found to show DIF; these were items that ask the respondent to name the correct season, day of the month, city, state, and 2 nearby streets, recall 3 objects, repeat the phrase no ifs, no ands, no buts, follow the command, “close your eyes,” and the command, “take the paper in your right hand, fold the paper in half with both hands, and put the paper down in your lap.” At the scale level, however, the MMSE did not show differential functioning. Conclusions Respondents to the English and Spanish versions of the MMSE are comparable on the basis of scale scores. However, assessments based on individual MMSE items may be misleading.

Morales, Leo S.; Flowers, Claudia; Gutierrez, Peter; Kleinman, Marjorie; Teresi, Jeanne A.

2006-01-01

256

Introduction to the theory of functional differential equations and their applications. Group approach  

Microsoft Academic Search

In this work, we give an introduction to the theory of nonlinear functional differential equations of pointwise type on a\\u000a finite interval, semi-axis, or axis. This approach is based on the formalism using group peculiarities of such differential\\u000a equations. For the main boundary-value problem and the Euler-Lagrange boundary-value problem, we consider the existence and\\u000a uniqueness of the solution, the continuous

Levon Andreevich Beklaryan

2006-01-01

257

21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.  

Code of Federal Regulations, 2013 CFR

... Manual gastroenterology-urology surgical instrument and accessories. 876...GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4730 Manual gastroenterology-urology surgical instrument and accessories....

2013-04-01

258

Starches of varied digestibilities differentially modify intestinal function in rats.  

PubMed

Starches of different digestibilities may enter the colon to different extents and alter colonic function. Male Fischer 344 rats were fed diets containing 25% cooked potato starch, arrowroot starch, high amylose cornstarch or raw potato starch for 6 wk. Fecal weight, transit time, colonic thymidine kinase activity (a marker for cell proliferation), and weight, starch content and pH of the cecum and proximal and distal colon were measured. Raw potato starch was much less completely digested than high amylose cornstarch, resulting in a 32-fold greater amount of undigested starch entering the cecum in the raw potato starch group. Both the high amylose cornstarch and raw potato starch diets significantly enhanced fecal weight and produced large intestinal hypertrophy, effects that were greatest in the raw potato starch group. Raw potato starch feeding was associated with the highest level of thymidine kinase activity, although the differences in thymidine kinase activity among the four groups were not significant. This diet also produced a 50% longer transit time. Entry of a large amount of raw potato starch into the colon resulted in greater luminal acidity, greater luminal bulk and slower transit. A much smaller amount of starch entered the colon in the high amylose cornstarch group and resulted in fecal bulking but no alteration in transit. PMID:8263598

Lajvardi, A; Mazarin, G I; Gillespie, M B; Satchithanandam, S; Calvert, R J

1993-12-01

259

Integral representation of entire functions and differential operators of infinite order  

NASA Astrophysics Data System (ADS)

In this article we derive an integral representation in certain spaces of entire functions of exponential type in \\mathbb C^n. To this end we use the isomorphism, given by the Laplace operator, between these spaces and the corresponding spaces of ultradistributions. Using this integral representation these functions admit a well-defined action of differential operators of infinite order with specific conditions on the characteristic function.

Odinokov, O. V.

1995-08-01

260

Differential Light Chain Assembly Influences Outer Arm Dynein Motor Function  

PubMed Central

Tctex1 and Tctex2 were originally described as potential distorters/sterility factors in the non-Mendelian transmission of t-haplotypes in mice. These proteins have since been identified as subunits of cytoplasmic and/or axonemal dyneins. Within the Chlamydomonas flagellum, Tctex1 is a subunit of inner arm I1. We have now identified a second Tctex1-related protein (here termed LC9) in Chlamydomonas. LC9 copurifies with outer arm dynein in sucrose density gradients and is missing only in those strains completely lacking this motor. Zero-length cross-linking of purified outer arm dynein indicates that LC9 interacts directly with both the IC1 and IC2 intermediate chains. Immunoblot analysis revealed that LC2, LC6, and LC9 are missing in an IC2 mutant strain (oda6-r88) that can assemble outer arms but exhibits significantly reduced flagellar beat frequency. This defect is unlikely to be due to lack of LC6, because an LC6 null mutant (oda13) exhibits only a minor swimming abnormality. Using an LC2 null mutant (oda12-1), we find that although some outer arm dynein components assemble in the absence of LC2, they are nonfunctional. In contrast, dyneins from oda6-r88, which also lack LC2, retain some activity. Furthermore, we observed a synthetic assembly defect in an oda6-r88 oda12-1 double mutant. These data suggest that LC2, LC6, and LC9 have different roles in outer arm assembly and are required for wild-type motor function in the Chlamydomonas flagellum.

DiBella, Linda M.; Gorbatyuk, Oksana; Sakato, Miho; Wakabayashi, Ken-ichi; Patel-King, Ramila S.; Pazour, Gregory J.; Witman, George B.; King, Stephen M.

2005-01-01

261

Evolution of the continental crust as recorded in accessory minerals  

NASA Astrophysics Data System (ADS)

Recent developments in precise in situ isotopic analysis by LA-ICPMS and SIMS allow correlating multiple isotopic systems within single grains of accessory minerals such as zircon and monazite. The combined isotope systematics have provided valuable insights into the evolution of the continental crust. Zircon, a common accessory phase in granitoids, can be precisely dated by the U-Pb system. Zircon Lu-Hf isotopic composition is a function of crustal residence time of the magmatic protolith, whereas the O isotopic composition is a sensitive record of reworking of mature sediments such as pelite. An integration of U-Pb, Lu-Hf and O isotopic data for detrital zircons from modern large rivers indicates that: (1) the preserved continental crust dominantly formed between 3.6 and 1.0 Ga, (2) the major mode of crustal development would change during the supercontinent cycle, i.e., the generation of juvenile crust during supercontinent fragmentation versus the stabilization of the generated crust via crustal remelting during supercontinent fragmentation, and (3) reworking of mature sediments increased abruptly at ca. 2.1 Ga. No granitoids are known to have survived since 4.03 Ga. Yet evidence of an even older evolved crust is provided by detrital zircons with ages up to 4.4 Ga from Mt. Narryer and Jack Hills metasedimentary rocks in the Yilgarn Craton, Western Australia. Recently, such Hadean zircons have been found from outside the Yilgarn Craton, indicating that the young Earth had widespread granitoid crust. In addition, another accessory phase, monazite, in the Mt. Narryer and Jack Hills metasedimentary rocks offers an unique opportunity to advance our knowledge of early crustal evolution. Monazite, a light rare earth element phosphate mineral, occurs as an igneous accessory phase particularly in low-Ca granitoids, in contrast to the occurrence of igneous zircon in a wide range of granitoids. U-Pb and Sm-Nd isotope systematic of monazite are analogous to U-Pb and Lu-Hf isotope systematics of zircon in that they define the timing of the crystallization and magmatic protolith formation (model age), respectively. The lack of monazites having >3.6 Ga crystallization ages as well as >4.0 Ga Nd model ages in the Mt. Narryer and Jack Hills metasedimentary rocks suggests that the source rocks of the Hadean detrital zircons are not low-Ca granitoids and therefore contained few monazites. Given that low-Ca granitoid magmas generated mainly by melting of pre-existing mid-lower crust, this finding may indicate minor intra-crustal melting and, by extension, crustal stabilization until ca. 3.6 Ga. This is consistent with the picture portrayed by the detrital zircons from modern rivers. Presumably, the hotter and rheologically weaker lithospheric mantle fostered many small plates and island arcs early in Earth's history, and the young arc crust was efficiently returned to the mantle via subduction. Accordingly, net growth of continental crust was essentially minor in early Earth's history despite high rates of crust generation.

Iizuka, Tsuyoshi

2013-04-01

262

Human embryonic stem cells differentiate into functional renal proximal tubular-like cells.  

PubMed

Renal cells are used in basic research, disease models, tissue engineering, drug screening, and in vitro toxicology. In order to provide a reliable source of human renal cells, we developed a protocol for the differentiation of human embryonic stem cells into renal epithelial cells. The differentiated stem cells expressed markers characteristic of renal proximal tubular cells and their precursors, whereas markers of other renal cell types were not expressed or expressed at low levels. Marker expression patterns of these differentiated stem cells and in vitro cultivated primary human renal proximal tubular cells were comparable. The differentiated stem cells showed morphological and functional characteristics of renal proximal tubular cells, and generated tubular structures in vitro and in vivo. In addition, the differentiated stem cells contributed in organ cultures for the formation of simple epithelia in the kidney cortex. Bioreactor experiments showed that these cells retained their functional characteristics under conditions as applied in bioartificial kidneys. Thus, our results show that human embryonic stem cells can differentiate into renal proximal tubular-like cells. Our approach would provide a source for human renal proximal tubular cells that are not affected by problems associated with immortalized cell lines or primary cells. PMID:23389418

Narayanan, Karthikeyan; Schumacher, Karl M; Tasnim, Farah; Kandasamy, Karthikeyan; Schumacher, Annegret; Ni, Ming; Gao, Shujun; Gopalan, Began; Zink, Daniele; Ying, Jackie Y

2013-02-06

263

Integrative genomic and functional analyses reveal neuronal subtype differentiation bias in human embryonic stem cell lines  

PubMed Central

The self-renewal and differentiation potential of human embryonic stem cells (hESCs) suggests that hESCs could be used for regenerative medicine, especially for restoring neuronal functions in brain diseases. However, the functional properties of neurons derived from hESC are largely unknown. Moreover, because hESCs were derived under diverse conditions, the possibility arises that neurons derived from different hESC lines exhibit distinct properties, but this possibility remains unexplored. To address these issues, we developed a protocol that allows stepwise generation from hESCs of cultures composed of ?70–80% human neurons that exhibit spontaneous synaptic network activity. Comparison of neurons derived from the well characterized HSF1 and HSF6 hESC lines revealed that HSF1- but not HSF6-derived neurons exhibit forebrain properties. Accordingly, HSF1-derived neurons initially form primarily GABAergic synaptic networks, whereas HSF6-derived neurons initially form glutamatergic networks. microRNA profiling revealed significant expression differences between the two hESC lines, suggesting that microRNAs may influence their distinct differentiation properties. These observations indicate that although both HSF1 and HSF6 hESCs differentiate into functional neurons, the two hESC lines exhibit distinct differentiation potentials, suggesting that they are preprogrammed. Information on hESC line-specific differentiation biases is crucial for neural stem cell therapy and establishment of novel disease models using hESCs.

Wu, Hao; Xu, Jun; Pang, Zhiping P.; Ge, Weihong; Kim, Kevin J.; Blanchi, Bruno; Chen, Caifu; Sudhof, Thomas C.; Sun, Yi E.

2007-01-01

264

Staphylococcus aureus and Staphylococcus epidermidis peptide pheromones produced by the accessory gene regulator agr system  

Microsoft Academic Search

The accessory gene regulator (agr) system of staphylococci regulates the expression of virulence factors in response to cell density. The extracellular signaling molecule encoded by this system is a thiolactone-containing pheromone peptide whose primary sequence varies among staphylococcal strains. A post-translational modification of the peptide is believed to be carried out by an enzyme with a novel function, AgrB. Staphylococcal

Michael Otto

2001-01-01

265

Perineal Accessory Scrotum with Congenital Lipoma: A Rare Case Report  

PubMed Central

A case of accessory scrotum in a 1-year-old boy is reported because of its rarity. A boy presented with a tumor mass attached with scrotum-like skin on its tip in the right side of perineum between the scrotum and anus. Both testes had descended into the scrotum. There was no other urological anomaly. Histological findings of the tumor indicated perineal lipoma, and the scrotum-like portion accessory scrotum. An overview of sequences during the normal development of male external genitalia has been provided and the deranged mechanism resulting in this anomaly has been reviewed with hypothesis regarding etiology of accessory scrotum.

Chatterjee, Souvik; Gajbhiye, Vishal; Nath, Sasanka; Ghosh, Dipak; Chattopadhyay, Sarbani; Das, Sukanta Kumar

2012-01-01

266

Oxygen Tension Modulates Differentiation and Primary Macrophage Functions in the Human Monocytic THP-1 Cell Line  

PubMed Central

The human THP-1 cell line is widely used as an in vitro model system for studying macrophage differentiation and function. Conventional culture conditions for these cells consist of ambient oxygen pressure (?20% v/v) and medium supplemented with the thiol 2-mercaptoethanol (2-ME) and serum. In consideration of the redox activities of O2 and 2-ME, and the extensive experimental evidence supporting a role for reactive oxygen species (ROS) in the differentiation and function of macrophages, we addressed the question of whether culturing THP-1 cells under a more physiologically relevant oxygen tension (5% O2) in the absence of 2-ME and serum would alter THP-1 cell physiology. Comparisons of cultures maintained in 18% O2 versus 5% O2 indicated that reducing oxygen tension had no effect on the proliferation of undifferentiated THP-1 cells. However, decreasing the oxygen tension to 5% O2 significantly increased the rate of phorbol ester-induced differentiation of THP-1 cells into macrophage-like cells as well as the metabolic activity of both undifferentiated and PMA-differentiated THP-1 cells. Removal of both 2-ME and serum from the medium decreased the proliferation of undifferentiated THP-1 cells but increased metabolic activity and the rate of differentiation under either oxygen tension. In differentiated THP-1 cells, lowering the oxygen tension to 5% O2 decreased phagocytic activity, the constitutive release of ?-hexosaminidase and LPS-induced NF-?B activation but enhanced LPS-stimulated release of cytokines. Collectively, these data demonstrate that oxygen tension influences THP-1 cell differentiation and primary macrophage functions, and suggest that culturing these cells under tightly regulated oxygen tension in the absence of exogenous reducing agent and serum is likely to provide a physiologically relevant baseline from which to study the role of the local redox environment in regulating THP-1 cell physiology.

Grodzki, Ana Cristina G.; Giulivi, Cecilia; Lein, Pamela J.

2013-01-01

267

Directed differentiation of human embryonic stem cells into functional retinal pigment epithelium cells.  

PubMed

Dysfunction and loss of retinal pigment epithelium (RPE) leads to degeneration of photoreceptors in age-related macular degeneration and subtypes of retinitis pigmentosa. Human embryonic stem cells (hESCs) may serve as an unlimited source of RPE cells for transplantation in these blinding conditions. Here we show the directed differentiation of hESCs toward an RPE fate under defined culture conditions. We demonstrate that nicotinamide promotes the differentiation of hESCs to neural and subsequently to RPE fate. In the presence of nicotinamide, factors from the TGF-beta superfamily, which presumably pattern RPE development during embryogenesis, further direct RPE differentiation. The hESC-derived pigmented cells exhibit the morphology, marker expression, and function of authentic RPE and rescue retinal structure and function after transplantation to an animal model of retinal degeneration caused by RPE dysfunction. These results are an important step toward the future use of hESCs to replenish RPE in blinding diseases. PMID:19796620

Idelson, Maria; Alper, Ruslana; Obolensky, Alexey; Ben-Shushan, Etti; Hemo, Itzhak; Yachimovich-Cohen, Nurit; Khaner, Hanita; Smith, Yoav; Wiser, Ofer; Gropp, Michal; Cohen, Malkiel A; Even-Ram, Sharona; Berman-Zaken, Yael; Matzrafi, Limor; Rechavi, Gideon; Banin, Eyal; Reubinoff, Benjamin

2009-10-01

268

Low-shear modelled microgravity environment maintains morphology and differentiated functionality of primary porcine hepatocyte cultures.  

PubMed

Hepatocytes cultured in conventional static culture rapidly lose polarity and differentiated function. This could be explained by gravity-induced sedimentation, which prevents formation of complete three-dimensional (3D) cell-cell/cell-matrix interactions and disrupts integrin-mediated signals (including the most abundant hepatic integrin alpha(5)beta(1)), important for cellular polarity and differentiation. Cell culture in a low fluid shear modelled microgravity (about 10(-2) g) environment promotes spatial colocation/self-aggregation of dissociated cells and induction of 3D differentiated liver morphology. Previously, we demonstrated the utility of a NASA rotary bioreactor in maintaining key metabolic functions and 3D aggregate formation of high-density primary porcine hepatocyte cultures over 21 days. Using serum-free chemically defined medium, without confounding interactions of exogenous bioscaffolding or bioenhancing surface materials, we investigated features of hepatic cellular polarity and differentiated functionality, including expression of hepatic integrin alpha(5), as markers of functional morphology. We report here that in the absence of exogenous biomatrix scaffolding, hepatocytes cultured in serum-free chemically defined medium in a microgravity environment rapidly (<24 h) form macroscopic (2-5 mm), compacted 3D hepatospheroid structures consisting of a shell of glycogen-positive viable cells circumscribing a core of eosinophilic cells. The spheroid shell layers exhibited ultrastructural, morphological and functional features of differentiated, polarized hepatic tissue including strong expression of the integrin alpha(5) subunit, functional bile canaliculi, albumin synthesis, and fine ultrastructure reminiscent of in vivo hepatic tissue. The low fluid shear microgravity environment may promote tissue-like self-organization of dissociated cells, and offer advantages over spheroids cultured in conventional formats to delineate optimal conditions for enhanced directed tissue self-assembly. PMID:20395654

Nelson, Leonard J; Walker, Simon W; Hayes, Peter C; Plevris, John N

2010-04-15

269

Discrete Jacobi elliptic function expansion method for nonlinear differential-difference equations  

NASA Astrophysics Data System (ADS)

In this paper, an improved algorithm is devised to derive exact travelling wave solutions of nonlinear differential-difference equations (DDEs) by means of Jacobi elliptic functions. With the aid of symbolic computation, we choose the integrable discrete nonlinear Schrödinger equation to illustrate the validity and advantages of the method. As a result, new and more general Jacobi elliptic function solutions are obtained, from which hyperbolic function solutions and trigonometric function solutions are derived when the modulus m?1 and 0. It is shown that the proposed method provides a more effective mathematical tool for nonlinear DDEs in mathematical physics.

Zhang, Sheng; Zhang, Hong-Qing

2009-10-01

270

Immunological functioning in Alzheimer's disease: Differential effects of relative left versus right temporoparietal dysfunction.  

PubMed

The cerebral hemispheres are differentially involved in regulating immunological functioning and the neuropathology associated with Alzheimer's disease (AD) is asymmetrical. Thus, subgroups of AD patients may exhibit different patterns of immunological dysfunction. We explored this possibility in a group of AD patients and found that patients with low white blood cell counts and low lymphocyte numbers exhibited better performance on tests of right temporoparietal functioning. Also, a significant positive relationship exists between lymph numbers and performance on a test of left temporoparietal functioning. Thus, some AD patients have greater immunological dysfunction based on relative left versus right temporoparietal functioning. PMID:23953971

Foster, Paul S; Roosa, Katelyn M; Williams, Megan R; Witt, John C; Heilman, Kenneth M; Drago, Valeria

2013-08-15

271

Comprehensive Analysis of Alternative Splicing and Functionality in Neuronal Differentiation of P19 Cells  

PubMed Central

Background Alternative splicing, which produces multiple mRNAs from a single gene, occurs in most human genes and contributes to protein diversity. Many alternative isoforms are expressed in a spatio-temporal manner, and function in diverse processes, including in the neural system. Methodology/Principal Findings The purpose of the present study was to comprehensively investigate neural-splicing using P19 cells. GeneChip Exon Array analysis was performed using total RNAs purified from cells during neuronal cell differentiation. To efficiently and readily extract the alternative exon candidates, 9 filtering conditions were prepared, yielding 262 candidate exons (236 genes). Semiquantitative RT-PCR results in 30 randomly selected candidates suggested that 87% of the candidates were differentially alternatively spliced in neuronal cells compared to undifferentiated cells. Gene ontology and pathway analyses suggested that many of the candidate genes were associated with neural events. Together with 66 genes whose functions in neural cells or organs were reported previously, 47 candidate genes were found to be linked to 189 events in the gene-level profile of neural differentiation. By text-mining for the alternative isoform, distinct functions of the isoforms of 9 candidate genes indicated by the result of Exon Array were confirmed. Conclusions/Significance Alternative exons were successfully extracted. Results from the informatics analyses suggested that neural events were primarily governed by genes whose expression was increased and whose transcripts were differentially alternatively spliced in the neuronal cells. In addition to known functions in neural cells or organs, the uninvestigated alternative splicing events of 11 genes among 47 candidate genes suggested that cell cycle events are also potentially important. These genes may help researchers to differentiate the roles of alternative splicing in cell differentiation and cell proliferation.

Suzuki, Hitoshi; Osaki, Ken; Sano, Kaori; Alam, A. H. M. Khurshid; Nakamura, Yuichiro; Ishigaki, Yasuhito; Kawahara, Kozo; Tsukahara, Toshifumi

2011-01-01

272

Assessment of Differential Item Functioning for Demographic Comparisons in the MOS SF36 Health Survey  

Microsoft Academic Search

Objective: To investigate whether items of the Medical Outcomes Study (MOS) 36-Item Short-Form Health Status Survey (SF-36) exhibited\\u000a differential item functioning (DIF) with respect to age, education, race, and gender. Methods: The data for this study come from two large national datasets, the MOS and the 1990 National Survey of Functional Health\\u000a Status (NSFHS). We used logistic regression to identify

Anthony J. Perkins; Timothy E. Stump; Patrick O. Monahan; Colleen A. McHorney

2006-01-01

273

Deletion of Smad2 in Mouse Liver Reveals Novel Functions in Hepatocyte Growth and Differentiation  

Microsoft Academic Search

Smad family proteins Smad2 and Smad3 are activated by transforming growth factor (TGF-)\\/activin\\/ nodal receptors and mediate transcriptional regulation. Although differential functional roles of Smad2 and Smad3 are apparent in mammalian development, the relative functional roles of Smad2 and Smad3 in postnatal systems remain unclear. We used Cre\\/loxP-mediated gene targeting for hepatocyte-specific deletion of Smad2 (S2HeKO) in adult mice and

Wenjun Ju; Atsushi Ogawa; Joerg Heyer; Dirk Nierhof; Liping Yu; Raju Kucherlapati; David A. Shafritz; Erwin P. Bottinger

2006-01-01

274

A Comparison of Two Area Measures for Detecting Differential Item Functioning  

Microsoft Academic Search

The area between two item response functions is often used as a measure of differential item functioning under item response theory. This area can be measured over either an open interval (i.e., exact) or closed interval. Formulas are presented for com puting the closed-interval signed and unsigned areas. Exact and closed-interval measures were estimated on data from a test with

Seock-Ho Kim; Allan S. Cohen

1991-01-01

275

Detecting Differential Item Functioning of a Course Satisfaction Instrument in the Presence of Multilevel Data  

ERIC Educational Resources Information Center

|The purposes of this study were to test for uniform differential item functioning (DIF) between male and female students on end-of-semester class evaluations in an introductory university science course and to demonstrate DIF detection methods that take into account the complex sampling mechanism that often underlies data used in such…

Finch, Holmes; French, Brian

2010-01-01

276

Identifying Differential Item Functioning in Multi-Stage Computer Adaptive Testing  

ERIC Educational Resources Information Center

The purpose of this study is to evaluate the performance of CATSIB (Computer Adaptive Testing-Simultaneous Item Bias Test) for detecting differential item functioning (DIF) when items in the matching and studied subtest are administered adaptively in the context of a realistic multi-stage adaptive test (MST). MST was simulated using a 4-item…

Gierl, Mark J.; Lai, Hollis; Li, Johnson

2013-01-01

277

Assessing Motor Skills as a Differentiating Feature between High Functioning Autism and Asperger's Disorder  

ERIC Educational Resources Information Center

|The purpose of this research was to investigate if motor skills could be used as a differentiating feature between Asperger's Disorder (AD) and High Functioning (HFA) in children under the age of 9 years, 0 months, in order to provide additional information regarding the usefulness and validity of distinguishing these two disorders. There is…

Cid, Maria R.

2011-01-01

278

Determinants of Differential Item Functioning in an Elementary Mathematics Test with Accommodations  

ERIC Educational Resources Information Center

|Those items or test characteristics that are likely to result in differential item functioning (DIF) across accommodated test forms in statewide tests have received little attention. An examination of elementary-level student performance across accommodated test forms in a large-scale mathematics assessment revealed DIF variations by grades,…

Chae, Soo Eun; Kim, Doyoung; Han, Jae-Ho

2012-01-01

279

Group-Specific Effects of Matching Subtest Contamination on the Identification of Differential Item Functioning  

ERIC Educational Resources Information Center

A differential item functioning (DIF) simulation study was conducted to explore the type and level of impact that contamination had on type I error and power rates in DIF analyses when the suspect item favored the same or opposite group as the DIF items in the matching subtest. Type I error and power rates were displayed separately for the…

Keiffer, Elizabeth Ann

2011-01-01

280

Analysis of School Context Effects on Differential Item Functioning Using Hierarchical Generalized Linear Models  

ERIC Educational Resources Information Center

This article considers and illustrates a strategy to study effects of school context on differential item functioning (DIF) in large-scale assessment. The approach employs a hierarchical generalized linear modeling framework to (a) detect DIF, and (b) identify school-level correlates of the between-group differences in item performance. To…

Cheong, Yuk Fai

2006-01-01

281

A Synthesis of the Peer-Reviewed Differential Bundle Functioning Research  

ERIC Educational Resources Information Center

|The purpose of this article was to present a synthesis of the peer-reviewed differential bundle functioning (DBF) research that has been conducted to date. A total of 16 studies were synthesized according to the following characteristics: tests used and learner groups, organizing principles used for developing bundles, DBF detection methods used,…

Banks, Kathleen

2013-01-01

282

Detection of Differential Item Functioning Using Lagrange Multiplier Tests. Research Report 96-02.  

ERIC Educational Resources Information Center

|In this paper it is shown that differential item functioning can be evaluated using the Lagrange multiplier test or C. R. Rao's efficient score test. The test is presented in the framework of a number of item response theory (IRT) models such as the Rasch model, the one-parameter logistic model, the two-parameter logistic model, the generalized…

Glas, Cees A. W.

283

A Comparison of Four Methods for Detecting Differential Item Functioning in Ordered Response Items  

ERIC Educational Resources Information Center

|Item bias is a major threat to measurement validity. Methods for detecting differential item functioning (DIF) are now commonly used to identify potentially biased items. DIF detection methods for dichotomous items are well developed, but those for ordinal items are less well developed. In this article, the authors compare four methods for…

Kristjansson, Elizabeth; Aylesworth, Richard; Mcdowell, Ian; Zumbo, Bruno D.

2005-01-01

284

Parent Ratings of ADHD Symptoms: Generalized Partial Credit Model Analysis of Differential Item Functioning across Gender  

ERIC Educational Resources Information Center

|Objective: Generalized partial credit model, which is based on item response theory (IRT), was used to test differential item functioning (DIF) for the "Diagnostic and Statistical Manual of Mental Disorders" (4th ed.), inattention (IA), and hyperactivity/impulsivity (HI) symptoms across boys and girls. Method: To accomplish this, parents…

Gomez, Rapson

2012-01-01

285

Descriptive and Inferential Procedures for Assessing Differential Item Functioning in Polytomous Items.  

ERIC Educational Resources Information Center

|Differential item functioning (DIF) assessment procedures for items with more than two ordered score categories, referred to as polytomous items, were evaluated. Three descriptive statistics (standardized mean difference and two procedures based on the SIBTEST computer program) and five inferential procedures were used. Conditions under which the…

Zwick, Rebecca; Thayer, Dorothy T.; Mazzeo, John

1997-01-01

286

An Investigation of Lord's Procedure for the Detection of Differential Item Functioning.  

ERIC Educational Resources Information Center

|Type I error rates of F. M. Lord's chi square test for differential item functioning were investigated using Monte Carlo simulations with marginal maximum likelihood estimation and marginal Bayesian estimation algorithms. Lord's chi square did not provide useful Type I error control for the three-parameter logistic model at these sample sizes.…

Kim, Seock-Ho; And Others

1994-01-01

287

A Comparison of Two Area Measures for Detecting Differential Item Functioning.  

ERIC Educational Resources Information Center

|The exact and closed-interval area measures for detecting differential item functioning are compared for actual data from 1,000 African-American and 1,000 white college students taking a vocabulary test with items intentionally constructed to favor 1 set of examinees. No real differences in detection of biased items were found. (SLD)|

Kim, Seock-Ho; Cohen, Allan S.

1991-01-01

288

Detection of Differential Item Functioning under the Graded Response Model with the Likelihood Ratio Test.  

ERIC Educational Resources Information Center

|Investigated Type I error rates of the likelihood-ratio test for the detection of differential item functioning (DIF) using Monte Carlo simulations under the graded-response model. Type I error rates were within theoretically expected values for all six combinations of sample sizes and ability-matching conditions at each of the nominal alpha…

Kim, Seock-Ho; Cohen, Allan S.

1998-01-01

289

Identification of Differential Item Functioning in Assessment Booklet Designs with Structurally Missing Data  

ERIC Educational Resources Information Center

|The Mantel-Haenszel procedure is a popular technique for determining items that may exhibit differential item functioning (DIF). Numerous studies have focused on the strengths and weaknesses of this procedure, but few have focused the performance of the Mantel-Haenszel method when structurally missing data are present as a result of test booklet…

Goodman, Joshua T.; Willse, John T.; Allen, Nancy L.; Klaric, John S.

2011-01-01

290

Correlates of Communalities as Matching Variables in Differential Item Functioning Analyses  

ERIC Educational Resources Information Center

Multivariate matching in Differential Item Functioning (DIF) analyses may contribute to understand the sources of DIF. In this context, detecting appropriate additional matching variables is a crucial issue. This present article argues that the variables which are correlated with communalities in item difficulties can be used as an additional…

Yildirim, Huseyin H.; Yildirim, Selda

2011-01-01

291

Dendritic Cell Responses to Early Murine Cytomegalovirus Infection: Subset Functional Specialization and Differential Regulation by Interferon ?  

Microsoft Academic Search

Differentiation of dendritic cells (DCs) into particular subsets may act to shape innate and adap- tive immune responses, but little is known about how this occurs during infections. Plasmacy- toid dendritic cells (PDCs) are major producers of interferon (IFN)- ? \\/ ? in response to many viruses. Here, the functions of these and other splenic DC subsets are further analyzed

Marc Dalod; Tanya Hamilton; Rachelle Salomon; Thais P. Salazar-Mather; Stanley C. Henry; John D. Hamilton; Christine A. Biron

2003-01-01

292

Sensitivity analysis for feedforward artificial neural networks with differentiable activation functions  

Microsoft Academic Search

A method for computing the network output sensitivities with respect to variations in the inputs for multilayer feedforward artificial neural networks with differentiable activation functions is presented. It is applied to obtain expressions for the first- and second-order sensitivities. An example is introduced along with a discussion to illustrate how the sensitivities are calculated and to show how they compare

Sherif Hashem; Honeywell SSDC

1992-01-01

293

Identification of Differential Item Functioning in Multiple-Group Settings: A Multivariate Outlier Detection Approach  

ERIC Educational Resources Information Center

|We focus on the identification of differential item functioning (DIF) when more than two groups of examinees are considered. We propose to consider items as elements of a multivariate space, where DIF items are outlying elements. Following this approach, the situation of multiple groups is a quite natural case. A robust statistics technique is…

Magis, David; De Boeck, Paul

2011-01-01

294

RankDE: learning a ranking function for information retrieval using differential evolution  

Microsoft Academic Search

Learning a ranking function is important for numerous tasks such as information retrieval (IR), question answering, and product recommendation. For example, in information retrieval, a Web search engine is required to rank and return a set of documents relevant to a query issued by a user. We propose RankDE, a ranking method that uses differential evolution (DE) to learn a

Danushka Bollegala; Nasimul Noman; Hitoshi Iba

2011-01-01

295

A Monte Carlo Study Investigating Missing Data, Differential Item Functioning, and Effect Size  

ERIC Educational Resources Information Center

The use of polytomous items in assessments has increased over the years, and as a result, the validity of these assessments has been a concern. Differential item functioning (DIF) and missing data are two factors that may adversely affect assessment validity. Both factors have been studied separately, but DIF and missing data are likely to occur…

Garrett, Phyllis

2009-01-01

296

ON A CONTROLLABILITY PROBLEM FOR SYSTEMS GOVERNED BY SEMILINEAR FUNCTIONAL DIFFERENTIAL INCLUSIONS IN BANACH SPACES  

Microsoft Academic Search

For a Banach space E, a given pair (p, x) ? (0 ,a ) × E ,a nd control system governed by a semilinear functional differential includion of the form x(t) ? Ax(t )+ F (t, x(t) ,T x) the existence of a mild trajectory of x(t) satisfying the condition x(p )= x is considered. Using topological methods we develop

Valeri Obukhovski; Paola Rubbioni

2000-01-01

297

Detection of Crossing Differential Item Functioning: A Comparison of Four Methods  

ERIC Educational Resources Information Center

|Differential item functioning (DIF) continues to receive attention both in applied and methodological studies. Because DIF can be an indicator of irrelevant variance that can influence test scores, continuing to evaluate and improve the accuracy of detection methods is an essential step in gathering score validity evidence. Methods for detecting…

Finch, W. Holmes; French, Brian F.

2007-01-01

298

Differential Item Functioning Analysis of the 2003-04 NHANES Physical Activity Questionnaire  

ERIC Educational Resources Information Center

Using differential item functioning (DIF) analyses, this study examined whether there were any DIF items in the National Health and Nutrition Examination Survey (NHANES) physical activity (PA) questionnaire. A subset of adult data from the 2003-04 NHANES study (n = 3,083) was used. PA items related to respondents' occupational, transportation,…

Gao, Yong; Zhu, Weimo

2011-01-01

299

Detecting Differential Item Functioning of Polytomous Items for an Ideal Point Response Process  

ERIC Educational Resources Information Center

|There has been growing use of ideal point models to develop scales measuring important psychological constructs. For meaningful comparisons across groups, it is important to identify items on such scales that exhibit differential item functioning (DIF). In this study, the authors examined several methods for assessing DIF on polytomous items…

Wang, Wei; Tay, Louis; Drasgow, Fritz

2013-01-01

300

Accommodations and Item-Level Analyses Using Mixture Differential Item Functioning Models  

ERIC Educational Resources Information Center

|The purpose of this study was to use differential item functioning (DIF) and latent mixture model analyses to explore factors that explain performance differences on a large-scale mathematics assessment between examinees allowed to use a calculator or who were afforded item presentation accommodations versus those who did not receive the same…

Scarpati, Stanley E.; Wells, Craig S.; Lewis, Christine; Jirka, Stephen

2011-01-01

301

Evaluation of Model Selection Strategies for Cross-Level Two-Way Differential Item Functioning Analysis  

ERIC Educational Resources Information Center

|Model specification issues on the cross-level two-way differential item functioning model were previously investigated by Patarapichayatham et al. (2009). Their study clarified that an incorrect model specification can easily lead to biased estimates of key parameters. The objective of this article is to provide further insights on the issue by…

Patarapichayatham, Chalie; Kamata, Akihito; Kanjanawasee, Sirichai

2012-01-01

302

Examining the Relationship between Race-Based Differential Item Functioning and Item Difficulty  

ERIC Educational Resources Information Center

|Recent research examining racial differences on standardized cognitive tests has focused on the impact of test item difficulty. Studies using data from the SAT and GRE have reported a correlation between item difficulty and differential item functioning (DIF) such that minority test takers are less likely than majority test takers to respond…

Scherbaum, Charles A.; Goldstein, Harold W.

2008-01-01

303

The MIMIC Method with Scale Purification for Detecting Differential Item Functioning  

ERIC Educational Resources Information Center

|This study implements a scale purification procedure onto the standard MIMIC method for differential item functioning (DIF) detection and assesses its performance through a series of simulations. It is found that the MIMIC method with scale purification (denoted as M-SP) outperforms the standard MIMIC method (denoted as M-ST) in controlling…

Wang, Wen-Chung; Shih, Ching-Lin; Yang, Chih-Chien

2009-01-01

304

Using Differential Item Functioning Procedures to Explore Sources of Item Difficulty and Group Performance Characteristics.  

ERIC Educational Resources Information Center

Differential item functioning (DIF) methodology for revealing sources of item difficulty and performance characteristics of different groups was explored. A total of 150 Scholastic Aptitude Test items and 132 Graduate Record Examination general test items were analyzed. DIF was evaluated for males and females and Blacks and Whites. (SLD)

Scheuneman, Janice Dowd; Gerritz, Kalle

1990-01-01

305

Research Article Semigroup Approach to Semilinear Partial Functional Differential Equations with Infinite Delay  

Microsoft Academic Search

We describe a semigroup,of abstract semilinear functional differential equations with infinite delay by the use of the Crandall Liggett theorem. We suppose that the linear part is not necessarily densely defined but satisfies the resolvent estimates of the Hille-Yosida theorem. We clarify the properties of the phase space ensuring equivalence between the equation under investigation and the nonlinear semigroup. Copyright

Hassane Bouzahir

306

Differential Item Functioning Analysis of the 2003-04 NHANES Physical Activity Questionnaire  

ERIC Educational Resources Information Center

|Using differential item functioning (DIF) analyses, this study examined whether there were any DIF items in the National Health and Nutrition Examination Survey (NHANES) physical activity (PA) questionnaire. A subset of adult data from the 2003-04 NHANES study (n = 3,083) was used. PA items related to respondents' occupational, transportation,…

Gao, Yong; Zhu, Weimo

2011-01-01

307

The Usefulness of Differential Item Functioning Methodology in Longitudinal Intervention Studies  

Technology Transfer Automated Retrieval System (TEKTRAN)

Perceived self-efficacy (SE) for engaging in physical activity (PA) is a key variable mediating PA change in interventions. The purpose of this study is to demonstrate the usefulness of item response modeling-based (IRM) differential item functioning (DIF) in the investigation of group differences ...

308

Differential Effects of a Tier Two Behavior Intervention Based on Function of Problem Behavior  

ERIC Educational Resources Information Center

The purpose of this study was to investigate the effectiveness of a tier two daily behavior card intervention and differential effects based on function of problem behavior. The participants were 36 elementary school students nominated for additional intervention beyond universal School-Wide Positive Behavior Support. Measures included…

McIntosh, Kent; Campbell, Amy L.; Carter, Deborah Russell; Dickey, Celeste Rossetto

2009-01-01

309

RIM: A Random Item Mixture Model to Detect Differential Item Functioning  

ERIC Educational Resources Information Center

In this paper we present a new methodology for detecting differential item functioning (DIF). We introduce a DIF model, called the random item mixture (RIM), that is based on a Rasch model with random item difficulties (besides the common random person abilities). In addition, a mixture model is assumed for the item difficulties such that the…

Frederickx, Sofie; Tuerlinckx, Francis; De Boeck, Paul; Magis, David

2010-01-01

310

Solving Nonlinear Fractional Differential Equation by Generalized Mittag-Leffler Function Method  

NASA Astrophysics Data System (ADS)

In this paper, we use Mittag—Leffler function method for solving some nonlinear fractional differential equations. A new solution is constructed in power series. The fractional derivatives are described by Caputo's sense. To illustrate the reliability of the method, some examples are provided.

A. A. M., Arafa; S. Z., Rida; A. A., Mohammadein; H. M., Ali

2013-06-01

311

RAZUMIKHIN-TYPE THEOREMS ON EXPONENTIAL STABILITY OF NEUTRAL STOCHASTIC FUNCTIONAL DIFFERENTIAL EQUATIONS  

Microsoft Academic Search

Recently, we initiated in (Systems Control Lett., 26 (1995), pp. 245-251) the study of exponential stability of neutral stochastic functional differential equations, and in this paper, we shall further our study in this area. We should emphasize that the main technique employed in this paper is the well-known Razumikhin argument and is completely different from those used in our previous

XUERONG MAO

1997-01-01

312

Does Impaired Executive Functioning Differentially Impact Verbal Memory Measures in Older Adults with Suspected Dementia?  

Microsoft Academic Search

The purpose of this study was to examine whether executive dysfunction differentially impacts list-learning and story recall tasks in a sample of older adults referred for suspected cognitive impairment. Older adults (N = 61) with mild cognitive impairment (MCI) or probable mild dementia, and those who did not meet criteria for diagnosis of dementia, were assessed using measures of executive function and

Brian L. Brooks; Linda E. Weaver; Charles T. Scialfa

2006-01-01

313

The Overtures of Preschool Social Skill Intervention AgentsDifferential Rates, Forms, and Functions  

Microsoft Academic Search

The purpose of this study was to examine the differential topographies and functions of social behaviors directed by normaly developing preschoolers to their playmates with autism. Social interaction data from intervention phases of a study by Kohler, Strain, Hoyson, DeCesare, Donina, and Rapp were analyzed in three different ways. First, thefrequency of four behaviors commonly included in social interaction training

Frank W. Kohler; Phillip S. Strain; Denise D. Shearer

1992-01-01

314

A posteriori finite element bounds for linear-functional outputs of elliptic partial differential equations  

Microsoft Academic Search

We present a domain decomposition finite element technique for efficiently generating lower and upper bounds to outputs which are linear functionals of the solutions to symmetric or nonsymmetric second-order coercive linear partial differential equations in two space dimensions. The method is based upon the construction of an augmented Lagrangian, in which the objective is a quadratic ‘energy’ reformulation of the

Marius Paraschivoiu; Jaime Peraire; Anthony T. Patera

1997-01-01

315

Differential Item Functioning Across Race in Aging Research: An Example Using a Social Support Measure  

Microsoft Academic Search

When conducting clinical assessments in older adults of different races, it is important for a clinician to feel confident that his\\/her instruments work equivalently well for all races. To explore the ability of instruments to measure constructs equally well across older adults of different races, we conducted differential item functioning (DIF) analysis on the Interpersonal Support Evaluation List (ISEL-12). Eight

Paul Sacco; Banghwa Lee Casado; G. Jay Unick

2010-01-01

316

Investigating Gender Differential Item Functioning Across Countries and Test Languages for PISA Science Items  

Microsoft Academic Search

This study uses PISA cycle 3 field trial data to investigate the relationships between gender differential item functioning (DIF) across countries and test languages for science items and their formats and the four other dimensions defined in PISA framework: focus, context, competency, and scientific knowledge. The data used were collected from 60 test language groups by 50 participating countries with

Luc T. Le

2009-01-01

317

Potential Sources of Differential Item Functioning in the Adaptation of Tests  

Microsoft Academic Search

This report shows a classification of differential item functioning (DIF) sources that have an effect on the adaptation of tests. This classification is based on linguistic and cultural criteria. Four general DIF sources are distinguished: cultural relevance, translation problems, morph syntactical differences, and semantic differences. The influence of these on the adaptation of tests is greater among those languages belonging

Paula Elosua; Alicia López-jaúregui

2007-01-01

318

Identification of Differential Item Functioning in Multiple-Group Settings: A Multivariate Outlier Detection Approach  

Microsoft Academic Search

We focus on the identification of differential item functioning (DIF) when more than two groups of examinees are considered. We propose to consider items as elements of a multivariate space, where DIF items are outlying elements. Following this approach, the situation of multiple groups is a quite natural case. A robust statistics technique is proposed to identify DIF items as

David Magis; Paul De Boeck

2011-01-01

319

Linguistic Complexity, Schematic Representations, and Differential Item Functioning for English Language Learners in Math Tests  

Microsoft Academic Search

This article examines nonmathematical linguistic complexity as a source of differential item functioning (DIF) in math word problems for English language learners (ELLs). Specifically, this study investigates the relationship between item measures of linguistic complexity, nonlinguistic forms of representation and DIF measures based on item response theory difficulty parameters in a state fourth-grade math test. This study revealed that the

Maria Martiniello

2009-01-01

320

Constructing Better Second Language Assessments Based on Differential Item Functioning Analysis  

Microsoft Academic Search

Differential item functioning (DIF) analysis can be used to great advantage in second language (L2) assessments. This study examined the differences in performance on L2 test items between groups from different first language backgrounds and suggested ways of improving L2 assessments. The study examined DIF on L2 (Hebrew) test items for two language groups: Arabic speakers and Russian speakers. Many

Avi Allalouf; Andrea Abramzon

2008-01-01

321

A differential item functioning analysis of the PSDQ with Turkish and New Zealand\\/Australian adolescents  

Microsoft Academic Search

ObjectiveThe use of item response theory models (IRT) in sport and exercise psychology has provided some unique insights into the quality of measure especially at the item level Fletcher. R. B. (August 2005). Detecting item bias in physical self-concept: an application of differential bundle functioning. In T. Morris, P. Terry, S. Gordon, S. Hanrahan, L. Ievleva, G. Kolt, & P. Tremayne

F. Hülya A?ç?; Richard B. Fletcher; Emine Ça?lar

2009-01-01

322

Extrapolation spaces and controllability of impulsive semilinear functional differential inclusions with infinite delay in Fréchet spaces  

Microsoft Academic Search

In this article, we investigate some classes of semilinear impulsive functional differential inclusions with infinite delay. It is assumed that the linear part is possibly neither densely defined nor it satisfies the Hille–Yosida condition on a Banach space, namely the extrapolated space. Our approach is based on the theory of extrapolation spaces combined with a recent Frigon nonlinear alternative for

Johnny Henderson; Abdelghani Ouahab

2006-01-01

323

DIFFERENTIAL ITEM FUNCTIONING AT POST ASSESSMENT BETWEEN TREATMENT AND CONTROL GROUPS FROM AN INCREASE IN KNOWLEDGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

There has been some concern that participation in an intervention and exposure to a measurement instrument can distort subsequent responses to a questionnaire, thereby biasing results. Differential Item Functioning (DIF) analysis with Item Response Modeling (IRM) can test these effects by testing f...

324

Evaluation of Model Selection Strategies for Cross-Level Two-Way Differential Item Functioning Analysis  

Microsoft Academic Search

Model specification issues on the cross-level two-way differential item functioning model were previously investigated by Patarapichayatham et al. (2009). Their study clarified that an incorrect model specification can easily lead to biased estimates of key parameters. The objective of this article is to provide further insights on the issue by specifically focusing on the impact of model selection strategies. Six

Chalie Patarapichayatham; Akihito Kamata; Sirichai Kanjanawasee

2012-01-01

325

Cauchy problem and Green's functions for first order differential operators and algebraic quantization  

SciTech Connect

Existence and uniqueness of advanced and retarded fundamental solutions (Green's functions) and of global solutions to the Cauchy problem is proved for a general class of first order linear differential operators on vector bundles over globally hyperbolic Lorentzian manifolds. This is a core ingredient to CAR-/CCR-algebraic constructions of quantum field theories on curved spacetimes, particularly for higher spin field equations.

Muehlhoff, Rainer [Berlin Mathematical School, TU Berlin, Mathematisches Institut, MA 2-2, Strasse des 17. Juni 136, 10623 Berlin (Germany)

2011-02-15

326

Identification of Differential Item Functioning in Assessment Booklet Designs with Structurally Missing Data  

ERIC Educational Resources Information Center

The Mantel-Haenszel procedure is a popular technique for determining items that may exhibit differential item functioning (DIF). Numerous studies have focused on the strengths and weaknesses of this procedure, but few have focused the performance of the Mantel-Haenszel method when structurally missing data are present as a result of test booklet…

Goodman, Joshua T.; Willse, John T.; Allen, Nancy L.; Klaric, John S.

2011-01-01

327

The main and the accessory olfactory systems interact in the control of mate recognition and sexual behavior.  

PubMed

In the field of sensory perception, one noticeable fact regarding olfactory perception is the existence of several olfactory subsystems involved in the detection and processing of olfactory information. Indeed, the vomeronasal or accessory olfactory system is usually conceived as being involved in the processing of pheromones as it is closely connected to the hypothalamus, thereby controlling reproductive function. By contrast, the main olfactory system is considered as a general analyzer of volatile chemosignals, used in the context of social communication, for the identification of the status of conspecifics. The respective roles played by the main and the accessory olfactory systems in the control of mate recognition and sexual behavior are at present still controversial. We summarize in this review recent results showing that both the main and accessory olfactory systems are able to process partially overlapping sets of sexual chemosignals and that both systems support complimentary aspects in mate recognition and in the control of sexual behavior. PMID:19374011

Keller, Matthieu; Baum, Michael J; Brock, Olivier; Brennan, Peter A; Bakker, Julie

2009-06-25

328

Compressive neuropathy of long thoracic nerve and accessory nerve secondary to heavy load bearing. A case report.  

PubMed

Carrying heavy loads that compress the shoulders is a possible etiological factor for both accessory and long thoracic nerve entrapment. In our patient, shouldering heavy loads damaged both nerves. A 27-year-old right-hand-dominant man was referred because of difficulty in raising his arms after a brief period of painful episodes due to heavy load bearing on both shoulders. Atrophic muscles around the shoulders, depressed and winged scapula were noted. An EMG confirmed entrapment of long thoracic and accessory nerves. An exercise program was instituted; 16 months after initial referral, though winged scapula was still noted, manual muscular strength had returned without functional limitation. PMID:17259913

Sahin, F; Yilmaz, F; Esit, N; Aysal, F; Kuran, B

2007-01-30

329

Accessory spleens: Clinical significance with particular reference to the recurrence of idiopathic thrombocytopenic purpura  

Microsoft Academic Search

One of the important stages during splenectomy is the search for accessory spleens. The average frequency of accessory spleens is an estimated 11%. In our own material in 611 patients who had splenectomy in hematological disorders, accessory spleens were found in 110 patients (18%). The surgical anatomy, embryology, and clinical significance of the accessory spleens, with particular reference to the

Witold J. Rudowski

1985-01-01

330

Cyclic adenosine monophosphate differentiated ?-endorphin neurons promote immune function and prevent prostate cancer growth  

PubMed Central

Pituitary adenylate cyclase-activating peptide (PACAP), a cAMP-activating agent, is highly expressed in the hypothalamus during the period when many neuroendocrine cells become differentiated from the neural stem cells (NSCs). Activation of the cAMP system in rat hypothalamic NSCs differentiated these cells into ?-endorphin (BEP)-producing neurons in culture. When these in vitro differentiated neurons were transplanted into the paraventricular nucleus (PVN) of the hypothalamus of an adult rat, they integrated well with the surrounding cells and produced BEP and its precursor gene product, proopiomelanocortin (POMC). Animals with BEP cell transplants demonstrated remarkable protection against carcinogen induction of prostate cancer. Unlike carcinogen-treated animals with control cell transplants, rats with BEP cell transplants showed rare development of glandular hyperplasia, prostatic intraepithelial neoplasia (PIN), or well differentiated adenocarcinoma with invasion after N-methyl-N-nitrosourea (MNU) and testosterone treatments. Rats with the BEP neuron transplants showed increased natural killer (NK) cell cytolytic function in the spleens and peripheral blood mononuclear cells (PBMCs), elevated levels of antiinflammatory cytokine IFN-?, and decreased levels of inflammatory cytokine tumor necrosis factor-? (TNF-?) in plasma. These results identified a critical role for cAMP in the differentiation of BEP neurons and revealed a previously undescribed role of these neurons in combating the growth and progression of neoplastic conditions like prostate cancer, possibly by increasing the innate immune function and reducing the inflammatory milieu.

Sarkar, Dipak K.; Boyadjieva, Nadka I.; Chen, Cui Ping; Ortiguela, Maria; Reuhl, Kenneth; Clement, E. Michael; Kuhn, Peter; Marano, Jason

2008-01-01

331

21 CFR 864.3600 - Microscopes and accessories.  

Code of Federal Regulations, 2013 CFR

...accessories (through a change in the light source) used for medical purposes include...that fluoresce under ultraviolet light. (3) Inverted stage microscopes...contained in bottles or tubes with the light source mounted above the specimen....

2013-04-01

332

21 CFR 884.2700 - Intrauterine pressure monitor and accessories.  

Code of Federal Regulations, 2010 CFR

...Gynecological Monitoring Devices § 884.2700 Intrauterine pressure monitor and accessories...a) Identification. An intrauterine pressure monitor is a device designed to detect and measure intrauterine and amniotic fluid...

2010-04-01

333

21 CFR 884.2700 - Intrauterine pressure monitor and accessories.  

Code of Federal Regulations, 2013 CFR

...Gynecological Monitoring Devices § 884.2700 Intrauterine pressure monitor and accessories...a) Identification. An intrauterine pressure monitor is a device designed to detect and measure intrauterine and amniotic fluid...

2013-04-01

334

21 CFR 884.2700 - Intrauterine pressure monitor and accessories.  

Code of Federal Regulations, 2010 CFR

...Gynecological Monitoring Devices § 884.2700 Intrauterine pressure monitor and accessories...a) Identification. An intrauterine pressure monitor is a device designed to detect and measure intrauterine and amniotic fluid...

2009-04-01

335

21 CFR 872.6640 - Dental operative unit and accessories.  

Code of Federal Regulations, 2010 CFR

... 2009-04-01 false Dental operative unit and accessories...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6640 Dental operative unit and...

2009-04-01

336

21 CFR 872.6640 - Dental operative unit and accessories.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 false Dental operative unit and accessories...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6640 Dental operative unit and...

2010-04-01

337

21 CFR 868.5860 - Pressure tubing and accessories.  

Code of Federal Regulations, 2013 CFR

...Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5860 Pressure tubing and accessories. (a) Identification....

2013-04-01

338

21 CFR 876.5980 - Gastrointestinal tube and accessories.  

Code of Federal Regulations, 2013 CFR

...gastro-urological irrigation tray (for gastrological use). (b) Classification. (1) Class II (special controls). The barium enema retention catheter and tip with or without a bag that is a gastrointestinal tube and accessory is exempt from the...

2013-04-01

339

21 CFR 876.5250 - Urine collector and accessories.  

Code of Federal Regulations, 2013 CFR

...device intended to collect urine. The device and accessories consist of tubing, a suitable receptacle, connectors, mechanical supports, and may include a means to prevent the backflow of urine or ascent of infection. The two kinds of urine...

2013-04-01

340

Accessory parotid gland lesions: case report and review of literature.  

PubMed

There are numerous causes for chronic cheek swelling, including masseteric hypertrophy, lymphadenopathy, diffuse inflammatory changes and neoplasia. We report an unusual case of a recurrent swelling as the result of sialolithiasis of an accessory parotid gland, which lay isolated from the main parotid gland along the Stensen's duct. The calculi developed in the accessory salivary tissue whereas all major salivary glands presented without sialolithiasis. Clinical findings as well as imaging results are shown and surgical management and histopathology are discussed. Hereby, for the first time we report a case with multiple calculi in an accessory parotid gland removed via a standard parotid incision. Further to this, we give a comprehensive review of literature on accessory parotid gland lesions. PMID:18193255

Stenner, M; Preuss, S F; Hüttenbrink, K-B; Klussmann, J P

2008-01-11

341

21 CFR 878.4700 - Surgical microscope and accessories.  

Code of Federal Regulations, 2013 CFR

...SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4700 Surgical...accessories is an AC-powered device intended for use during surgery to provide a magnified view of the surgical...

2013-04-01

342

21 CFR 878.1800 - Speculum and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Diagnostic Devices § 878.1800 Speculum and accessories. (a) Identification. A...

2013-04-01

343

21 CFR 878.4160 - Surgical camera and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4160 Surgical camera and accessories. (a) Identification. A...

2013-04-01

344

21 CFR 876.5010 - Biliary catheter and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5010 Biliary catheter and accessories. (a) Identification. A...

2013-04-01

345

21 CFR 876.5130 - Urological catheter and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5130 Urological catheter and accessories. (a) Identification....

2013-04-01

346

21 CFR 876.4890 - Urological table and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4890 Urological table and accessories. (a) Identification. A...

2013-04-01

347

21 CFR 876.5090 - Suprapubic urological catheter and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5090 Suprapubic urological catheter and accessories. (a)...

2013-04-01

348

21 CFR 876.5540 - Blood access device and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5540 Blood access device and accessories. (a) Identification....

2013-04-01

349

21 CFR 884.4120 - Gynecologic electrocautery and accessories.  

Code of Federal Regulations, 2010 CFR

...tissue contact with an electrically heated probe. It is used to excise cervical lesions, perform biopsies, or treat chronic cervicitis under direct visual observation. This generic type of device may include the following accessories: an electrical...

2010-04-01

350

21 CFR 884.4120 - Gynecologic electrocautery and accessories.  

Code of Federal Regulations, 2010 CFR

...tissue contact with an electrically heated probe. It is used to excise cervical lesions, perform biopsies, or treat chronic cervicitis under direct visual observation. This generic type of device may include the following accessories: an electrical...

2009-04-01

351

21 CFR 872.3980 - Endosseous dental implant accessories.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3980 Endosseous dental implant accessories. (a) Identification. Endosseous dental...

2013-04-01

352

21 CFR 876.5900 - Ostomy pouch and accessories.  

Code of Federal Regulations, 2013 CFR

...material or urine following an ileostomy, colostomy, or ureterostomy (a surgically created opening of the small intestine, large intestine, or the ureter on the surface of the body). This generic type of device and its accessories...

2013-04-01

353

21 CFR 872.4200 - Dental handpiece and accessories.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4200 Dental handpiece and accessories. (a) Identification. A dental handpiece and...

2013-04-01

354

21 CFR 872.4920 - Dental electrosurgical unit and accessories.  

Code of Federal Regulations, 2013 CFR

...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4920 Dental electrosurgical unit and accessories...intended to cut or remove soft tissue or to control bleeding during surgical procedures in the oral cavity. An electrical current...

2013-04-01

355

Controlled Speed Accessory Drive Program: Programmatic Environmental Assessment.  

National Technical Information Service (NTIS)

This document is a programmatic environmental assessment of the Department of Energy's Controlled Speed Accessory Drive (CSAD) program and alternatives. Its purpose is to evaluate CSAD alternatives to assure that environmental priorities are considered at...

1980-01-01

356

Epicardial electric shock ablation of the left lateral accessory pathway  

Microsoft Academic Search

Fifty patients with drug-resistant, recurrent tachyarrhythmias causing Wolff—Parkinson—White syndrome underwent surgery between 1990 and 1992. All recognized surgical methods for accessory pathway destruction were performed. Epicardial electric shock ablation was first used as a method of surgically destroying an accessory atrioventricular pathway in 1983. This technique avoids the need for cardioplegia and hypothermia during operation. The procedure is based on

K. Suwalski; M. Pytkowski; P. ?elazny; D. Wojciechowski; E. Sitkowska; Z. Sadowski; W. Sitkowski

1995-01-01

357

Choosing the correct accessory for each stoma type: an update.  

PubMed

There are many people with a stoma that report a good quality of life. However, for many, problems can be encountered that can directly affect them. The use of a stoma accessory, in addition to the stoma appliance, can often benefit people with a stoma in relation to treating sore skin or preventing appliances from leakage. This article focuses on some of the more common stoma accessories, including when and why they should be used. PMID:24037328

Burch, Jennie

2013-09-12

358

Accessory parotid gland lesions: case report and review of literature  

Microsoft Academic Search

There are numerous causes for chronic cheek swelling, including masseteric hypertrophy, lymphadenopathy, diffuse inflammatory\\u000a changes and neoplasia. We report an unusual case of a recurrent swelling as the result of sialolithiasis of an accessory parotid\\u000a gland, which lay isolated from the main parotid gland along the Stensen’s duct. The calculi developed in the accessory salivary\\u000a tissue whereas all major salivary

M. Stenner; S. F. Preuss; K.-B. Hüttenbrink; J. P. Klussmann

2008-01-01

359

DNA polymerase ? and ? switch by sharing accessory subunits of DNA polymerase ?.  

PubMed

Translesion DNA synthesis is an important branch of the DNA damage tolerance pathway that assures genomic integrity of living organisms. The mechanisms of DNA polymerase (Pol) switches during lesion bypass are not known. Here, we show that the C-terminal domain of the Pol ? catalytic subunit interacts with accessory subunits of replicative DNA Pol ?. We also show that, unlike other members of the human B-family of DNA polymerases, the highly conserved and similar C-terminal domains of Pol ? and Pol ? contain a [4Fe-4S] cluster coordinated by four cysteines. Amino acid changes in Pol ? that prevent the assembly of the [4Fe-4S] cluster abrogate Pol ? function in UV mutagenesis. On the basis of these data, we propose that Pol switches at replication-blocking lesions occur by the exchange of the Pol ? and Pol ? catalytic subunits on a preassembled complex of accessory proteins retained on DNA during translesion DNA synthesis. PMID:22465957

Baranovskiy, Andrey G; Lada, Artem G; Siebler, Hollie M; Zhang, Yinbo; Pavlov, Youri I; Tahirov, Tahir H

2012-03-30

360

Density functional theory for differential capacitance of planar electric double layers in ionic liquids  

SciTech Connect

The differential capacitance of electric double layers in ionic liquids and its correlation with the surface charge density, ion size and concentration are studied within the framework of the classical density functional theory (DFT). As prescribed by previous analytical theories, DFT is able to reproduce the transition in the differential capacitance versus the surface potential curve from the 'camel' shape to the 'bell' shape when the ionic density increases. However, DFT predicts alternating layers of cations and anions at the charged surface that cannot be described by the classical Gouy-Chapman-Stern model and its modifications.

Jiang, Deen [ORNL; Meng, Dong [University of California, Riverside; Wu, Jianzhong [University of California, Riverside

2011-01-01

361

Human Endometrial Stromal Stem Cells Differentiate into Megakaryocytes with the Ability to Produce Functional Platelets  

PubMed Central

Human endometrium is a high dynamic tissue that contains endometrial stromal stem cells (hESSCs). The hESSCs have been differentiated into a number of cell lineages. However, differentiation of hESSCs into megakaryocytes (MKs) has not yet been investigated. The aim of this study was to investigate the feasibility of MK generation from hESSCs and subsequent production of functional platelets (PLTs). In our study, hESSCs were cultured from endometrial stromal cells as confirmed by positive stromal cell specific markers (CD90 and CD29) and negative hematopoietic stem cell markers (CD45 and CD34) expression. Then, hESSCs were differentiated in a medium supplemented with thrombopoietin (TPO) for 18 days. The MK differentiation was analyzed by flow cytometry and confocal microscopy. The differentiation medium was collected for PLT production analysis by flow cytometry, transmission electron microscopy and functional measurements. Our results show: 1) MKs were successfully generated from hESSCs as identified by expression of specific markers (CD41a: 1±0.09% and 39±3.0%; CD42b: 1.2±0.06% and 28±2.0%, control vs. differentiation) accompanied with reduction of pluripotent transcription factors (Oct4 and Sox2) expression; 2) The level of PLTs in the differentiation medium was 16±1 number/µl as determined by size (2–4 µm) and CD41a expression (CD41a: 1±0.4% and 90±2.0%, control vs. differentiation); 3) Generated PLTs were functional as evidenced by the up-regulation of CD62p expression and fibrinogen binding following thrombin stimulation; 4) Released PLTs showed similar ultra-structure characteristics (alpha granules, vacuoles and dense tubular system) as PLTs from peripheral blood determined by electron microscopic analysis. Data demonstrate the feasibility of generating MKs from hESSCs, and that the generated MKs release functional PLTs. Therefore, hESSCs could be a potential new stem cell source for in vitro MK/PLT production.

Zhang, Cheng; Stegeman, Samantha; Pfaff-Amesse, Teresa; Zhang, Ying; Zhang, Wenfeng; Amesse, Lawrence; Chen, Yanfang

2012-01-01

362

The accessory subunit of mitochondrial DNA polymerase c determines the DNA content of mitochondrial nucleoids in human cultured cells  

Microsoft Academic Search

The accessory subunit of mitochondrial DNA poly- merase c, POLGb, functions as a processivity factor in vitro. Here we show POLGb has additional roles in mitochondrial DNA metabolism. Mitochondrial DNA is arranged in nucleoprotein complexes, or nucleoids, which often contain multiple copies of the mitochondrial genome. Gene-silencing of POLGb increased nucleoid numbers, whereas over- expression of POLGb reduced the number

M. Di Re; H. Sembongi; J. He; A. Reyes; T. Yasukawa; P. Martinsson; L. J. Bailey; S. Goffart; J. D. Boyd-Kirkup; T. S. Wong; A. R. Fersht; J. N. Spelbrink; I. J. Holt

363

An unusual cause of subtalar pain and instability: accessory calcaneus.  

PubMed

We report on a 45-yr-old male sports instructor with chronic pain and instability of the ankle. He was a recreational basketball player, but because of repeated ankle sprains and chronic subtalar pain this activity became impossible. The radiologic findings were compatible with the diagnosis of accessory calcaneus. In an initial therapeutic approach the patient was treated conservatively with taping and physical therapy, but this failed to relieve the symptoms. Next, a ligamentoplasty was performed. The instability improved, but the pain remained the same. Finally the accessory calcaneus was resected and short term follow-up was unremarkable. Accessory calcaneus is an uncommon anatomical variation that may cause subtalar pain and instability. Resection of the accessory bone may be necessary to provide relief of symptoms. Accessory calcaneus can be well demonstrated on CT, SPECT-CT, and MR. MR and nuclear medicine can indicate instability of the accessory bone by showing bone marrow edema on MR or uptake on fusion imaging. PMID:23405487

Boulet, C; De Maeseneer, M; Everaert, H; Kichouh, M; De Mey, J; Shahabpour, M

364

Differentiation-Inducing Factor-1 and -2 Function also as Modulators for Dictyostelium Chemotaxis  

PubMed Central

Background In the early stages of development of the cellular slime mold Dictyostelium discoideum, chemotaxis toward cAMP plays a pivotal role in organizing discrete cells into a multicellular structure. In this process, a series of signaling molecules, such as G-protein-coupled cell surface receptors for cAMP, phosphatidylinositol metabolites, and cyclic nucleotides, function as the signal transducers for controlling dynamics of cytoskeleton. Differentiation-inducing factor-1 and -2 (DIF-1 and DIF-2) were originally identified as the factors (chlorinated alkylphenones) that induce Dictyostelium stalk cell differentiation, but it remained unknown whether the DIFs had any other physiologic functions. Methodology/Principal Findings To further elucidate the functions of DIFs, in the present study we investigated their effects on chemotaxis under various conditions. Quite interestingly, in shallow cAMP gradients, DIF-1 suppressed chemotaxis whereas DIF-2 promoted it greatly. Analyses with various mutants revealed that DIF-1 may inhibit chemotaxis, at least in part, via GbpB (a phosphodiesterase) and a decrease in the intracellular cGMP concentration ([cGMP]i). DIF-2, by contrast, may enhance chemotaxis, at least in part, via RegA (another phosphodiesterase) and an increase in [cGMP]i. Using null mutants for DimA and DimB, the transcription factors that are required for DIF-dependent prestalk differentiation, we also showed that the mechanisms for the modulation of chemotaxis by DIFs differ from those for the induction of cell differentiation by DIFs, at least in part. Conclusions/Significance Our findings indicate that DIF-1 and DIF-2 function as negative and positive modulators for Dictyostelium chemotaxis, respectively. To our knowledge, this is the first report in any organism of physiologic modulators (small molecules) for chemotaxis having differentiation-inducing activity.

Kuwayama, Hidekazu; Kubohara, Yuzuru

2009-01-01

365

Distinctive Accessory Minerals, Textures and Crystal Habits in Biofilm Associated Gypsum Deposits  

NASA Astrophysics Data System (ADS)

Gypsum-depositing environments near Guerrero Negro, Baja California Sur, Mexico were investigated in order to differentiate the influence of microbial activity versus nonbiological processes upon sedimentary fabrics and minerals. Field sites were located in sabkhas (mudflats and anchialine pools) and in seawater concentration ponds in the salt production facility operated by Exportadora de Sal, S. A. Gypsum (CaSO4.2H2O) was classified according to sedimentary environment (e.g., mudflats, anchialine pools, saltern ponds, surface and subsurface sediments), sedimentary texture, mineral composition, crystal habit, brine composition and other geochemical and biological factors. Gypsum types that develop in the absence of biofilms include water column precipitates (pelagic grains) and subsedimentary crystalline discs that form from phreatic brine ripening. Subsedimentary gypsum forming in sabkha environments had a sinuous axial microtexture and poikilitically enclosed detrital particles whereas water column precipitates exhibited euhedral prismatic habits and extensive penetrative twinning. Gypsum that was influenced by biofilms included cumulate crusts and gypsooids / gypsolite developing in anchialine pools and in saltern concentration ponds. Gypsum precipitating within subaqueous benthic microbial mats, or biofilm/sediment surfaces offered compelling evidence of biofilm influence on crystal textures and habits. Biofilm effects include irregular high relief surface textures, accessory minerals (elemental sulfur, Ca-carbonate, Sr/Ca-sulfate, Mg-oxide and Mg- sulfate) and distinctive crystal habits. Elemental sulfur, Ca-carbonate, and Sr/Ca-sulfate are known byproducts of bacterially mediated sulfate reduction (BSR). Populations of gypsum crystals within biofilms exhibited euhedral to lensoidal morphologies with unique equant and distorted prismatic forms. These forms had been shown to arise from form- and face-specific inhibition by bioorganic functional groups (Cody, 1991; Cody and Cody 1991). Biofilms therefore may play an active role in influencing brine chemistry, inducing crystallization and modifying crystal habits, evidence of which is preserved in grain morphologies.

Vogel, M.; Des Marais, D.; Jahnke, L.; Parenteau, M.

2008-12-01

366

Topical Hesperidin Improves Epidermal Permeability Barrier Function and Epidermal Differentiation in Normal Murine Skin  

PubMed Central

Orange peel extract appears to exhibit beneficial effects on skin whitening, inflammation, UVB protection, as well as keratinocyte proliferation. In the present study, we determine whether topical hesperidin influences epidermal permeability barrier function and its underlying mechanisms. Hairless mice were treated topically with 2% hesperidin or 70% ethanol alone twice daily for 6 days. At the end of treatment, basal barrier function as well as transepidermal water loss (TEWL) was measured 2 and 4 hours post barrier disruption. Epidermal proliferation and differentiation were evaluated by immunohistochemical staining and Western blot analysis. Additionally, lamellar body density and secretion were assessed by electron microscopy. Although there were no significant differences in basal barrier function, in comparison to control animals, topical hesperidin significantly accelerated barrier recovery at both 2 and 4 hours after acute barrier abrogation. Enhanced barrier function in hesperidin-treated skin correlated with stimulation of both epidermal proliferation and differentiation, as well as enhanced lamellar body secretion. These results indicate that topical hesperidin enhances epidermal permeability barrier homeostasis at least in part due to stimulation of epidermal proliferation, differentiation, as well as lamellar body secretion.

Hou, Maihua; Man, Mona; Man, Wenyan; Zhu, Wenyuan; Hupe, Melanie; Park, Kyungho; Crumrine, Debra; Elias, Peter M.; Man, Mao-Qiang

2012-01-01

367

Butyrate affects differentiation, maturation and function of human monocyte-derived dendritic cells and macrophages  

PubMed Central

We studied the in vitro effects of butyric acid on differentiation, maturation and function of dendritic cells (DC) and macrophages (M?) generated from human monocytes. A non-toxic dose of butyrate was shown to alter the phenotypic differentiation process of DC as assessed by a persistence of CD14, and a decreased CD54, CD86 and HLA class II expression. The more immature differentiation stage of treated cells was confirmed further by their increased phagocytic capability, their altered capacity to produce IL-10 and IL-12, and their weak allostimulatory abilities. Butyrate also altered DC terminal maturation, regardless of the maturation inducer, as demonstrated by a strong down-regulation of CD83, a decreased expression of CD40, CD86 and HLA class II. Similarly, butyrate altered M? differentiation, down-regulating the expression of the restricted membrane antigens and reducing the phagocytic capacity of treated cells. To investigate further the mechanism by which butyrate hampers the monocyte dual differentiation pathway, we studied the effects of 1,25(OH)2D3 alone or in combination with butyrate on the phenotypic features of DC. Unlike 1,25(OH)2D3, butyrate inhibited DC differentiation without redirecting it towards M?. Combined treatment gave rise to a new cell subset (CD14high, CD86 and HLA-DRlow) phenotypically distinct from monocytes. These results reveal an alternative mechanism of inhibition of DC and M? differentiation. Altogether, our data demonstrate a novel immune suppression property of butyrate that may modulate both inflammatory and immune responses and support further the interest for butyrate and its derivatives as new immunotherapeutic agents.

Millard, A L; Mertes, P M; Ittelet, D; Villard, F; Jeannesson, P; Bernard, J

2002-01-01

368

A Comparison of Unidimensional and Three-Dimensional Differential Item Functioning Analysis Using Two-Dimensional Data  

ERIC Educational Resources Information Center

Oshima, Raju, and Flowers demonstrated the use of an item response theory-based technique for analyzing differential item function (DIF) and differential test function for dichotomously scored data that are intended to be multidimensional. Their study assumed that the number of intended-to-be measured dimensions was correctly identified. In…

Snow, Teresa K.; Oshima, T. C.

2009-01-01

369

Using a Taxonomy of Differential Step Functioning to Improve the Interpretation of DIF in Polytomous Items: An Illustration  

Microsoft Academic Search

The assessment of differential item functioning (DIF) in polytomous items addresses between-group differences in measurement properties at the item level, but typically does not inform which score levels may be involved in the DIF effect. The framework of differential step functioning (DSF) addresses this issue by examining between-group differences in the measurement properties at each step underlying the polytomous response

Randall D. Penfield; Karina Alvarez; Okhee Lee

2008-01-01

370

Local chromatin dynamics of transcription factors imply cell-lineage specific functions during cellular differentiation  

PubMed Central

Chromatin dynamics across cellular differentiation states is an emerging perspective from which the mechanism of global gene expression regulation may be better understood. While the roles of some histone marks have been partially interpreted in terms of their association with gene transcription, the dynamics of histone marks from a loci-specific perspective during cellular differentiation is not well studied. We established a method to systematically assess the histone modification variations of genes across various cellular differentiation states. We calculated the histone modification variation scores of H3K4me3, H3K27me3 and H3K36me3 for over 1300 curated transcription factors (TFs) during human blood cell differentiation. Hematopoietic-specific TFs (identified by literature mining) were significantly overrepresented by TFs with higher histone modification variation scores. Hierarchical clustering of all TFs based on the histone modification variation scores defined a group of TFs where known or potential hematopoietic-specific TFs were remarkably enriched. Our results suggest that local chromatin state dynamics of transcription factors across cellular differentiation states could imply cell lineage-specific functions. More importantly, our method can be applied to broader systems, holding the promise to discover de novo, lineage-specific TFs by interrogating their histone modification dynamics across cell lineages.

Tian, Rui; Feng, Jianxing; Cai, Xiaopeng; Zhang, Yong

2012-01-01

371

Ablation of the calcium-sensing receptor in keratinocytes impairs epidermal differentiation and barrier function.  

PubMed

The calcium-sensing receptor (CaR) has an essential role in mediating Ca(2+)-induced keratinocyte differentiation in vitro. In this study, we generated keratinocyte-specific CaR knockout ((Epid)CaR(-/-)) mice to investigate the function of the CaR in epidermal development in vivo. (Epid)CaR(-/-) mice exhibited a delay in permeability barrier formation during embryonic development. Ion capture cytochemistry detected the loss of the epidermal Ca(2+) gradient in the (Epid)CaR(-/-) mice. The expression of terminal differentiation markers and key enzymes mediating epidermal sphingolipid transport and processing in the (Epid)CaR(-/-) epidermis was significantly reduced. The (Epid)CaR(-/-) epidermis displayed a marked decrease in the number of lamellar bodies (LBs) and LB secretion, thinner lipid-bound cornified envelopes, and a defective permeability barrier. Consistent with in vivo results, epidermal keratinocytes cultured from (Epid)CaR(-/-) mice demonstrated abnormal Ca(2+)(i) handling and diminished differentiation. The impairment in epidermal differentiation and permeability barrier in (Epid)CaR(-/-) mice maintained on a low calcium (0.02%) diet is more profound and persistent with age than in (Epid)CaR(-/-) mice maintained on a normal calcium (1.3%) diet. Deleting CaR perturbs the epidermal Ca(2+) gradient and impairs keratinocyte differentiation and permeability barrier homeostasis, indicating a key role for the CaR in normal epidermal development. PMID:22622426

Tu, Chia-Ling; Crumrine, Debra A; Man, Mao-Qiang; Chang, Wenhan; Elalieh, Hashem; You, Michael; Elias, Peter M; Bikle, Daniel D

2012-05-24

372

The accessory subunit of DNA polymerase ? is essential for mitochondrial DNA maintenance and development in Drosophila melanogaster  

PubMed Central

DNA polymerase ?, Pol ?, is the key replicative enzyme in animal mitochondria. The Drosophila enzyme is a heterodimer comprising catalytic and accessory subunits of 125 kDa and 35 kDa, respectively. Both subunits have been cloned and characterized in a variety of model systems, and genetic mutants of the catalytic subunit were first identified in Drosophila, as chemically induced mutations that disrupt larval behavior (tamas). Mutations in the gene encoding the accessory subunit have not yet been described in any organism. Here, we report the consequences of null mutations upon mitochondrial DNA (mtDNA) replication and morphology, cell proliferation, and organismal viability. Mutations in the accessory subunit cause lethality during early pupation, concomitant with loss of mtDNA and mitochondrial mass, and reduced cell proliferation in the central nervous system. Surprisingly, the function of the central nervous system and muscle, as assessed in a locomotion assay, are only marginally affected. This finding is in contrast to our previous findings that disruption in the function of the catalytic subunit causes severe reduction in larval locomotion. We discuss our results in the context of current hypotheses for the function of the accessory subunit in mtDNA replication.

Iyengar, Balaji; Luo, Ningguang; Farr, Carol L.; Kaguni, Laurie S.; Campos, Ana Regina

2002-01-01

373

Myelin basic protein functions as a microtubule stabilizing protein in differentiated oligodendrocytes.  

PubMed

Myelin basic protein (MBP) is an oligodendrocyte-specific protein essential for oligodendrocyte morphogenesis at late stages of cell differentiation. There is evidence that the morphogenetic function of MBP is mediated by MBP interaction with the cytoskeleton. Thus, an MBP/cytoplasmic microtubule association has been reported, and MBP has Ca(2+)/calmodulin-regulated microtubule cold-stabilizing activity in vitro. However, the unambiguous demonstration of a microtubule-stabilizing activity for MBP in cells has been difficult because oligodendrocytes contain variants of STOP (stable tubule only polypeptide) proteins, which are responsible for microtubule cold stability in different cell types. Herein, we have used genetic mouse models and RNA interference to assay independently the microtubule cold-stabilizing activities of MBP and of STOP in developing oligodendrocytes. In wild-type oligodendrocytes, microtubules were cold stable throughout maturation, which is consistent with the presence of STOP proteins from early stages of differentiation. In contrast, in oligodendrocytes from STOP-deficient mice, microtubules were cold labile in the absence of MBP expression or when MBP expression was restricted to the cell body and became stable in fully differentiated oligodendrocytes, where MBP is expressed in cell extensions. The suppression of MBP by RNA interference in STOP-deficient oligodendrocytes suppressed microtubule cold stability. Additionally, STOP suppression in oligodendrocytes derived from shiverer mice that lack MBP led to the complete suppression of microtubule cold stability at all stages of cell differentiation. These results demonstrate that both STOP and MBP function as microtubule-stabilizing proteins in differentiating oligodendrocytes and could be important for the morphogenetic function of MBP. PMID:16773649

Galiano, M R; Andrieux, A; Deloulme, J C; Bosc, C; Schweitzer, A; Job, D; Hallak, M E

2006-08-15

374

Twist1 function in endocardial cushion cell proliferation, migration, and differentiation during heart valve development  

PubMed Central

Twist1 is a bHLH transcription factor that regulates cell proliferation, migration, and differentiation in embryonic progenitor cell populations and transformed tumor cells. While much is known about Twist1’s function in a variety of mesenchymal cell types, the role of Twist1 in endocardial cushion cells is unknown. Twist1 gain and loss of function experiments were performed in primary chicken endocardial cushion cells in order to elucidate its role in endocardial cushion development. These studies indicate that Twist1 can induce endocardial cushion cell proliferation as well as promote endocardial cushion cell migration. Furthermore, Twist1 is subject to BMP regulation and can induce expression of cell migration marker genes including Periostin, Cadherin 11, and Mmp2 while repressing markers of valve cell differentiation including Aggrecan. Previously, Tbx20 has been implicated in endocardial cushion cell proliferation and differentiation, and in the current study, Tbx20 also promotes cushion cell migration. Twist1 can induce Tbx20 expression, while Tbx20 does not affect Twist1 expression. Taken together, these data indicate a role for Twist1 upstream of Tbx20 in promoting cell proliferation and migration and repressing differentiation in endocardial cushion cells during embryonic development.

Shelton, Elaine L.; Yutzey, Katherine E.

2008-01-01

375

Th1/Th2 Differentiation and B Cell Function by the Atypical PKCs and Their Regulators  

PubMed Central

The members of the atypical Protein Kinase Cs (aPKC) kinase subfamily, PKC? and PKC?/?, as well as their adapters, p62 and Par-6, form part of the PB1-domain-containing group of signaling regulators. Both adapters serve to locate through heterotypic interactions the aPKCs into the NF-?B and cell polarity pathways, respectively. Both signaling cascades have been critically implicated in T cell function in vitro and in vivo. The analysis of gene-knockout (KO) mice deficient in the different PB1 molecules is providing more definitive information on the actual role that the aPKCs and other PB1-containing molecules play in B cell biology and T cell polarity, survival, and differentiation toward the different effector lineages in vivo and at the cellular ex vivo level. Here we discuss recent data generated from the analysis of KO mice linking the control of cell polarity by PKC?/? and PKC?, their adapter p62, and the Par-4 inhibitor, in the control of B and T cell signaling and differentiation. Altogether, these genetic and biochemical evidences reveal the existence of a PB1-orchestrated signaling network that acts to control Th2 differentiation in vitro and in vivo, and the gene transcriptional programs that are essential during the B cell maturation and function and Th2 differentiation.

Martin, Pilar; Moscat, Jorge

2012-01-01

376

Parent Ratings of ADHD Symptoms: Differential Symptom Functioning Across Malaysian Malay and Chinese Children  

Microsoft Academic Search

This study examined differential symptom functioning (DSF) in ADHD symptoms across Malay and Chinese children in Malaysia.\\u000a Malay (N?=?571) and Chinese (N?=?254) parents completed the Disruptive Behavior Rating Scale, which lists the DSM-IV ADHD symptoms. DSF was examined using\\u000a the multiple indicators multiple causes (MIMIC) structural equation modeling procedure. Although DSF was found for a single\\u000a inattention (IA) symptom and

Rapson Gomez; Alasdair Vance

2008-01-01

377

Differentiation-Inducing Factor1 and -2 Function also as Modulators for Dictyostelium Chemotaxis  

Microsoft Academic Search

BackgroundIn the early stages of development of the cellular slime mold Dictyostelium discoideum, chemotaxis toward cAMP plays a pivotal role in organizing discrete cells into a multicellular structure. In this process, a series of signaling molecules, such as G-protein-coupled cell surface receptors for cAMP, phosphatidylinositol metabolites, and cyclic nucleotides, function as the signal transducers for controlling dynamics of cytoskeleton. Differentiation-inducing

Hidekazu Kuwayama; Yuzuru Kubohara; Paulo Lee Ho

2009-01-01

378

Differential item functioning (DIF) analyses of health-related quality of life instruments using logistic regression  

Microsoft Academic Search

BACKGROUND: Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise when testing for DIF in HRQoL instruments. We focus on logistic regression methods, which are often used because

Neil W Scott; Peter M Fayers; Neil K Aaronson; Andrew Bottomley; Alexander de Graeff; Mogens Groenvold; Chad Gundy; Michael Koller; Morten A Petersen; Mirjam AG Sprangers

2010-01-01

379

Retinoblastoma protein functions as a molecular switch determining white versus brown adipocyte differentiation  

Microsoft Academic Search

Adipocyte precursor cells give raise to two major cell populations with different physiological roles: white and brown adipocytes. Here we demonstrate that the retinoblastoma protein (pRB) regulates white vs. brown adipocyte differentiation. Functional inactivation of pRB in wild-type mouse embryo fibroblasts (MEFs) and white preadipocytes by expression of simian virus 40 large T antigen results in the expression of the

Jacob B. Hansen; Claus Jørgensen; Rasmus K. Petersen; Philip Hallenborg; Rita de Matteis; Hans A. Bøye; Natasa Petrovic; Sven Enerbäck; Jan Nedergaard; Saverio Cinti; Hein Te Riele; Karsten Kristiansen

2004-01-01

380

Periodic solutions of integro-differential equations in vector-valued function spaces  

Microsoft Academic Search

Operator-valued Fourier multipliers are used to study well-posedness of integro-differential equations in Banach spaces. Both strong and mild periodic solutions are considered. Strong well-posedness corresponds to maximal regularity which has proved very efficient in the handling of nonlinear problems. We are concerned with a large array of vector-valued function spaces: Lebesgue–Bochner spaces Lp, the Besov spaces Bp,qs (and related spaces

Valentin Keyantuo; Carlos Lizama

2009-01-01

381

Ligand-functionalized Biomaterial Surfaces: Controlled Regulation of Signaling Pathways to Direct Cell Differentiation  

Microsoft Academic Search

Appropriate ligand–receptor interactions are critical in triggering signal transduction pathways in cells. This, among other\\u000a functions, can direct stem cell differentiation into specific lineages. Although many of these ligands act as soluble agents,\\u000a a significant number are present on surfaces of neighboring cells or as bound components on the extracellular matrix. Recent\\u000a research has focused on identifying such interactions, quantitatively

Myung Hee Kim; Krishnendu Roy

382

Oscillation and nonoscillation of second order differential equations with delay depending on the unknown function  

NASA Astrophysics Data System (ADS)

Oscillation and nonoscillation of the second order differential equation with delay depending on the unknown function(r(t)x'(t))'+f(t,x(t),x([up triangle, open](t,x(t))))=0in the case when [integral operator][infinity]ds/r(s)<[infinity] holds are consider. The results obtained in this paper can be conjugated with the theorems given by Bainov et al. [J. Comput. Appl. Math. 91 (1998) 87-96].

Xu, Zhiting

2008-05-01

383

Bone Marrow-Derived Human Mesenchymal Stem Cells Express Cardiomyogenic Proteins But Do Not Exhibit Functional Cardiomyogenic Differentiation Potential  

PubMed Central

Despite their paracrine activites, cardiomyogenic differentiation of bone marrow (BM)-derived mesenchymal stem cells (MSCs) is thought to contribute to cardiac regeneration. To systematically evaluate the role of differentiation in MSC-mediated cardiac regeneration, the cardiomyogenic differentiation potential of human MSCs (hMSCs) and murine MSCs (mMSCs) was investigated in vitro and in vivo by inducing cardiomyogenic and noncardiomyogenic differentiation. Untreated hMSCs showed upregulation of cardiac tropopin I, cardiac actin, and myosin light chain mRNA and protein, and treatment of hMSCs with various cardiomyogenic differentiation media led to an enhanced expression of cardiomyogenic genes and proteins; however, no functional cardiomyogenic differentiation of hMSCs was observed. Moreover, co-culturing of hMSCs with cardiomyocytes derived from murine pluripotent cells (mcP19) or with murine fetal cardiomyocytes (mfCMCs) did not result in functional cardiomyogenic differentiation of hMSCs. Despite direct contact to beating mfCMCs, hMSCs could be effectively differentiated into cells of only the adipogenic and osteogenic lineage. After intramyocardial transplantation into a mouse model of myocardial infarction, Sca-1+ mMSCs migrated to the infarcted area and survived at least 14 days but showed inconsistent evidence of functional cardiomyogenic differentiation. Neither in vitro treatment nor intramyocardial transplantation of MSCs reliably generated MSC-derived cardiomyocytes, indicating that functional cardiomyogenic differentiation of BM-derived MSCs is a rare event and, therefore, may not be the main contributor to cardiac regeneration.

Siegel, Georg; Krause, Petra; Wohrle, Stefanie; Nowak, Patrick; Ayturan, Miriam; Kluba, Torsten; Brehm, Bernhard R.; Neumeister, Birgid; Kohler, David; Rosenberger, Peter; Just, Lothar; Northoff, Hinnak

2012-01-01

384

6,4'-Dihydroxy-7-methoxyflavanone inhibits osteoclast differentiation and function.  

PubMed

6,4'-Dihydroxy-7-methoxyflavanone (DMF) is a flavonoid isolated from Heartwood Dalbergia odorifera. It has been known that DMF has antioxidant, anti-inflammatory and neuroprotective effects. DMF, however, the efficacy of bone related diseases has not been reported. In this study, we determined DMF's efficacy on osteoclasts differentiation and function using in vitro bone marrow macrophage osteoclast differentiation culture system. DMF inhibited receptor activators of nuclear factor kappa-B ligand (RANKL) induced osteoclastogenesis dose dependently. In addition, DMF decreased osteoclast function through disruption of actin ring formation and consequently suppression of the pit-forming activity of mature osteoclasts. Mechanistically, DMF inhibited RANKL-induced expression of nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1) and c-Fos via inhibition of mitogen activated protein kinases (MAPKs) pathway. Collectively, the inhibition of osteoclasts differentiation and function by DMF suggests that DMF can be a potential therapeutic molecule for osteoclastogenic bone diseases such osteoporosis, rheumatoid arthritis and periodontal diseases. PMID:23420617

Im, Nam-Kyung; Choi, Je-Yong; Oh, Hyuncheol; Kim, Youn-Chul; Jeong, Gil-Saeng

2013-02-19

385

Spatial congregation of STAT binding directs selective nuclear architecture during T-cell functional differentiation.  

PubMed

Higher-order genome organization shows tissue-specific patterns. However, functional relevance and the mechanisms shaping the genome architecture are poorly understood. Here we report a profound shift from promiscuous to highly selective genome organization that accompanies the effector lineage choice of differentiating T cells. As multipotent naive cells receive antigenic signals and commit to a T helper (Th) pathway, the genome-wide contacts of a lineage-specific cytokine locus are preferentially enriched for functionally relevant genes. Despite the establishment of divergent interactomes and global reprogramming of transcription in Th1 versus Th2, the overall expression status of the contact genes is surprisingly similar between the two lineages. Importantly, during differentiation, the genomic contacts are retained and strengthened precisely at DNA binding sites of the specific lineage-determining STAT transcription factor. In cells from the specific STAT knock-out mouse, the signature cytokine locus is unable to shed the promiscuous contacts established in the naive T cells, indicating the importance of genomic STAT binding. Altogether, the global aggregation of STAT binding loci from genic and nongenic regions highlights a new role for differentiation-promoting transcription factors in direct specification of higher-order nuclear architecture through interacting with regulatory regions. Such subnuclear environments have significant implications for efficient functioning of the mature effector lymphocytes. PMID:23212947

Hakim, Ofir; Sung, Myong-Hee; Nakayamada, Shingo; Voss, Ty C; Baek, Songjoon; Hager, Gordon L

2012-12-03

386

Characterizing regulatory and functional differentiation between maize mesophyll and bundle sheath cells by transcriptomic analysis.  

PubMed

To study the regulatory and functional differentiation between the mesophyll (M) and bundle sheath (BS) cells of maize (Zea mays), we isolated large quantities of highly homogeneous M and BS cells from newly matured second leaves for transcriptome profiling by RNA sequencing. A total of 52,421 annotated genes with at least one read were found in the two transcriptomes. Defining a gene with more than one read per kilobase per million mapped reads as expressed, we identified 18,482 expressed genes; 14,972 were expressed in M cells, including 53 M-enriched transcription factor (TF) genes, whereas 17,269 were expressed in BS cells, including 214 BS-enriched TF genes. Interestingly, many TF gene families show a conspicuous BS preference in expression. Pathway analyses reveal differentiation between the two cell types in various functional categories, with the M cells playing more important roles in light reaction, protein synthesis and folding, tetrapyrrole synthesis, and RNA binding, while the BS cells specialize in transport, signaling, protein degradation and posttranslational modification, major carbon, hydrogen, and oxygen metabolism, cell division and organization, and development. Genes coding for several transporters involved in the shuttle of C(4) metabolites and BS cell wall development have been identified, to our knowledge, for the first time. This comprehensive data set will be useful for studying M/BS differentiation in regulation and function. PMID:22829318

Chang, Yao-Ming; Liu, Wen-Yu; Shih, Arthur Chun-Chieh; Shen, Meng-Ni; Lu, Chen-Hua; Lu, Mei-Yeh Jade; Yang, Hui-Wen; Wang, Tzi-Yuan; Chen, Sean C-C; Chen, Stella Maris; Li, Wen-Hsiung; Ku, Maurice S B

2012-07-24

387

Small functional groups for controlled differentiation of hydrogel-encapsulated human mesenchymal stem cells  

NASA Astrophysics Data System (ADS)

Cell-matrix interactions have critical roles in regeneration, development and disease. The work presented here demonstrates that encapsulated human mesenchymal stem cells (hMSCs) can be induced to differentiate down osteogenic and adipogenic pathways by controlling their three-dimensional environment using tethered small-molecule chemical functional groups. Hydrogels were formed using sufficiently low concentrations of tether molecules to maintain constant physical characteristics, encapsulation of hMSCs in three dimensions prevented changes in cell morphology, and hMSCs were shown to differentiate in normal growth media, indicating that the small-molecule functional groups induced differentiation. To our knowledge, this is the first example where synthetic matrices are shown to control induction of multiple hMSC lineages purely through interactions with small-molecule chemical functional groups tethered to the hydrogel material. Strategies using simple chemistry to control complex biological processes would be particularly powerful as they could make production of therapeutic materials simpler, cheaper and more easily controlled.

Benoit, Danielle S. W.; Schwartz, Michael P.; Durney, Andrew R.; Anseth, Kristi S.

2008-10-01

388

Anatrophic nephrolithotomy: preservation of renal function demonstrated by differential quantitative radionuclide renal scans  

SciTech Connect

Differential quantitative radionuclide renal scans have been used to confirm that early removal of staghorn calculi by anatrophic nephrolithotomy preserves renal parenchyma without significant renal damage by the surgical procedure. The /sup 99m/technetium diethylenetriaminepentaacetic acid scan was useful in predicting recovery of function in the involved kidney, while the /sup 131/iodine orthoiodohippurate scan provided a quantitative evaluation of the effect of the surgical procedure on individual kidney function. All of 13 consecutive patients evaluated by /sup 131/iodine orthoiodohippurate renal scans had stable or improved effective renal plasma flow to the involved kidney and an unchanged or improved total excretory index 6 months after nephrolithotomy.

Belis, J.A.; Morabito, R.A.; Kandzari, S.J.; Lai, J.C.; Gabriele, O.F.

1981-06-01

389

Drosophila E-Cadherin Functions in Hematopoietic Progenitors to Maintain Multipotency and Block Differentiation  

PubMed Central

A fundamental question in stem cell biology concerns the regulatory strategies that control the choice between multipotency and differentiation. Drosophila blood progenitors or prohemocytes exhibit key stem cell characteristics, including multipotency, quiescence, and niche dependence. As a result, studies of Drosophila hematopoiesis have provided important insights into the molecular mechanisms that control these processes. Here, we show that E-cadherin is an important regulator of prohemocyte fate choice, maintaining prohemocyte multipotency and blocking differentiation. These functions are reminiscent of the role of E-cadherin in mammalian embryonic stem cells. We also show that mis-expression of E-cadherin in differentiating hemocytes disrupts the boundary between these cells and undifferentiated prohemocytes. Additionally, upregulation of E-cadherin in differentiating hemocytes increases the number of intermediate cell types expressing the prohemocyte marker, Patched. Furthermore, our studies indicate that the Drosophila GATA transcriptional co-factor, U-shaped, is required for E-cadherin expression. Consequently, E-cadherin is a downstream target of U-shaped in the maintenance of prohemocyte multipotency. In contrast, we showed that forced expression of the U-shaped GATA-binding partner, Serpent, repressed E-cadherin expression and promoted lamellocyte differentiation. Thus, U-shaped may maintain E-cadherin expression by blocking the inhibitory activity of Serpent. Collectively, these observations suggest that GATA:FOG complex formation regulates E-cadherin levels and, thereby, the choice between multipotency and differentiation. The work presented in this report further defines the molecular basis of prohemocyte cell fate choice, which will provide important insights into the mechanisms that govern stem cell biology.

Gao, Hongjuan; Wu, Xiaorong; Fossett, Nancy

2013-01-01

390

Cellular Trafficking of Phospholamban and Formation of Functional Sarcoplasmic Reticulum During Myocyte DIfferentiation  

SciTech Connect

The sarco/endoplasmic reticulum Ca-ATPase (SERCA) family members are transmembrane proteins that play an essential role in regulating intracellular calcium levels. Phospholamban (PLB), a 52 amino acid phosphoprotein, regulates SERCA activity in adult heart and skeletal muscle. Using the C2C12 myocyte cell line, we find endogenous PLB constitutively expressed in both myoblasts and myotubes, whereas SERCA expression coincides with activation of the differentiation program. PLB has a punctuate distribution in myoblasts changing to a reticular distribution in myotubes where it colocalizes with SERCAs. To examine the distribution and dynamics of PLB and SERCA, we expressed fluorescent fusion proteins (GFP, CFP, and YFP) of PLB and SERCA in myoblasts. Coexpressed PLB and SERCA localize to distinct cellular compartments in myoblasts but begin to colocalize as cells differentiate. Fluorescence Recovery After Photobleaching (FRAP) studies show different recovery patterns for each protein in myoblasts confirming their localization to distinct compartments. To extend these studies, we created stable cell lines expressing O6-alkylguanine-DNA alkyltransferase (AGT) fusions with PLB or SERCA to track their localization as myocytes differentiate. These experiments demonstrate that PLB localizes to punctate vesicles in myoblasts and adopts a reticular distribution that coincides with SERCA distribution after differentiation. Colocalization experiments indicate that a subset of PLB in myoblasts colocalizes with endosomes, Golgi, and the plasma membrane however PLB also localizes to other, as yet unidentified vesicles. Our results indicate that differentiation plays a critical role in regulating PLB distribution to ensure its colocalization within the same cellular compartment as SERCA in differentiated cells. The presence and altered distribution of PLB in undifferentiated myoblasts raises the possibility that this protein has additional functions distinct from SERCA regulation.

Stenoien, David L.; Knyushko, Tatyana V.; Londono, Monica P.; Opresko, Lee; Mayer, M. Uljana; Brady, Scott T.; Squier, Thomas C.; Bigelow, Diana J.

2007-06-01

391

Functional Dissection of HOXD Cluster Genes in Regulation of Neuroblastoma Cell Proliferation and Differentiation  

PubMed Central

Retinoic acid (RA) can induce growth arrest and neuronal differentiation of neuroblastoma cells and has been used in clinic for treatment of neuroblastoma. It has been reported that RA induces the expression of several HOXD genes in human neuroblastoma cell lines, but their roles in RA action are largely unknown. The HOXD cluster contains nine genes (HOXD1, HOXD3, HOXD4, and HOXD8-13) that are positioned sequentially from 3? to 5?, with HOXD1 at the 3? end and HOXD13 the 5? end. Here we show that all HOXD genes are induced by RA in the human neuroblastoma BE(2)-C cells, with the genes located at the 3? end being activated generally earlier than those positioned more 5? within the cluster. Individual induction of HOXD8, HOXD9, HOXD10 or HOXD12 is sufficient to induce both growth arrest and neuronal differentiation, which is associated with downregulation of cell cycle-promoting genes and upregulation of neuronal differentiation genes. However, induction of other HOXD genes either has no effect (HOXD1) or has partial effects (HOXD3, HOXD4, HOXD11 and HOXD13) on BE(2)-C cell proliferation or differentiation. We further show that knockdown of HOXD8 expression, but not that of HOXD9 expression, significantly inhibits the differentiation-inducing activity of RA. HOXD8 directly activates the transcription of HOXC9, a key effector of RA action in neuroblastoma cells. These findings highlight the distinct functions of HOXD genes in RA induction of neuroblastoma cell differentiation.

Yang, Liqun; Mao, Ling; Wang, Xiangwei; McCarthy, Brian A.; Huang, Shuang; Ding, Han-Fei

2012-01-01

392

Differential diagnosis of adults with ADHD: the role of executive function and self-regulation.  

PubMed

Adult ADHD is conceptualized as a disorder of age-inappropriate behavior that occurs because of maldevelopment of 2 related neuropsychological domains. The neuropsychological symptoms seen in adults with ADHD may be explained by deficits in executive function, which can be broadly defined as a set of neurocognitive processes that allow for the organization of behavior across time so as to attain future goals. Executive function is comprised of 2 broad domains: inhibition and metacognition. Inhibition encompasses the ability to inhibit motor, verbal, cognitive, and emotional activities. In turn, deficits in inhibition contribute to deficits in the development of 4 aspects of executive function in the domain of metacognition, which include nonverbal working memory, verbal working memory, planning and problem-solving, and emotional self-regulation. Understanding the ways in which deficits in executive function contribute to the symptoms of ADHD can help in differentiating ADHD from disorders that share similar characteristics. PMID:20667287

Barkley, Russell A

2010-07-01

393

A new twist on an old pathway - accessory Sec systems  

PubMed Central

Summary The export of proteins from their site of synthesis in the cytoplasm across the inner membrane is an important aspect of bacterial physiology. Because the location of extracytoplasmic proteins is ideal for host-pathogen interactions, protein export is also important to bacterial virulence. In bacteria there are conserved protein export systems that are responsible for the majority of protein export: the general secretion (Sec) pathway and the twin-arginine translocation (Tat) pathway. In some bacteria, there are also specialized export systems dedicated to exporting specific subsets of proteins. In this review, we discuss a specialized export system that exists in some Gram-positive bacteria and mycobacteria – the accessory Sec system. The common element to the accessory Sec system is an accessory SecA protein called SecA2. Here we present our current understanding of accessory Sec systems in Streptococcus gordonii, Streptococcus parasanguinis, Mycobacterium smegmatis, Mycobacterium tuberculosis, and Listeria monocytogenes, making an effort to highlight apparent similarities and differences between the systems. We also review the data showing that accessory Sec systems can contribute to bacterial virulence.

Rigel, Nathan W.; Braunstein, Miriam

2008-01-01

394

Differentiation of Human Embryonic Stem Cells Into Functional Ovarian Granulosa-like Cells.  

PubMed

Context: Granulosa cells are important for the development and maturation of oocytes. The dysfunction of granulosa cells may contribute to abnormal folliculogenesis and steroidogenesis. Objective: Our objective was to establish an effective culture system to differentiate human embryonic stem cells (hESCs) into granulosa cells. Design: For differentiation of hESCs to granulosa cells, we used multistep approaches comprising in vitro treatments with cocktails of growth factors. Expression of mesendoderm/intermediate plate mesoderm markers, and granulosa cell markers were analyzed by real time-PCR, Western blotting, immunofluorescence, and flow cytometry. The production of estradiol and anti-Mullerian hormone (AMH) was analyzed by ELISA. Results: Gene expression analyses showed the progress of hESCs to primitive streak-mesendoderm, intermediate plate mesoderm, and finally to functional granulosa-like cells that expressed the granulosa cell-specific forkhead transcription factor FOXL2, estrogen synthetase cytochrome P450 19A1 (CYP19A1), AMH, the type 2 AMH receptor (AMHR2), and the FSH receptor (FSHR). However, they did not express the LH receptor (LHR). Western blot showed that AMHR2 and CYP19A1 levels in differentiated hESCs were higher than in undifferentiated cells. Flow cytometry showed that the percentage of AMHR2-, FSHR-, and CYP19A1-positive cells increased to 36%, 12%, and 34%, respectively, after differentiation for 12 days. These granulosa-like cells were also capable of producing AMH and aromatizing testosterone to estradiol, suggesting that they were biologically functional. Conclusions: We successfully established an effective protocol to generate functional ovarian granulosa-like cells from hESCs. The derivation of these cells opens new avenues for the further study and potential application of these cells in human folliculogenesis and steroidogenesis. PMID:23884780

Lan, Chen-Wei; Chen, Mei-Jou; Jan, Pey-Shynan; Chen, Hsin-Fu; Ho, Hong-Nerng

2013-07-24

395

Dynamic Rewiring of the Drosophila Retinal Determination Network Switches Its Function from Selector to Differentiation  

PubMed Central

Organ development is directed by selector gene networks. Eye development in the fruit fly Drosophila melanogaster is driven by the highly conserved selector gene network referred to as the “retinal determination gene network,” composed of approximately 20 factors, whose core comprises twin of eyeless (toy), eyeless (ey), sine oculis (so), dachshund (dac), and eyes absent (eya). These genes encode transcriptional regulators that are each necessary for normal eye development, and sufficient to direct ectopic eye development when misexpressed. While it is well documented that the downstream genes so, eya, and dac are necessary not only during early growth and determination stages but also during the differentiation phase of retinal development, it remains unknown how the retinal determination gene network terminates its functions in determination and begins to promote differentiation. Here, we identify a switch in the regulation of ey by the downstream retinal determination genes, which is essential for the transition from determination to differentiation. We found that central to the transition is a switch from positive regulation of ey transcription to negative regulation and that both types of regulation require so. Our results suggest a model in which the retinal determination gene network is rewired to end the growth and determination stage of eye development and trigger terminal differentiation. We conclude that changes in the regulatory relationships among members of the retinal determination gene network are a driving force for key transitions in retinal development.

Sansores-Garcia, Leticia; Jusiak, Barbara; Halder, Georg; Mardon, Graeme

2013-01-01

396

Mcl-1 Functions as Major Epidermal Survival Protein Required for Proper Keratinocyte Differentiation  

PubMed Central

Rapid down-regulation of the anti-apoptotic Bcl-2 family protein Mcl-1 is required for UV-induced apoptosis, underlining an important role for Mcl-1 in epidermal pathology. To determine if Mcl-1 has a specific role in normal keratinocyte (KC) biology, Mcl-1 was down-regulated in human KCs by RNAi and these KCs were induced to differentiate in organotypic raft cultures. Mcl-1 shRNA organotypic cultures showed increased levels of spontaneous premature apoptosis, implicating Mcl-1 as an essential KC survival protein. Mcl-1 down-regulated cultures also had reduced granular and cornified layers, and produced lower levels of cross-linked protein and cornified envelopes. Cornification could only partially be rescued with the general caspase inhibitor z-VAD, suggesting that reduced cornification was not entirely due to premature apoptosis. Differentiation markers (K1, K10, filaggrin, loricrin, cleaved caspase-14) were normally expressed in control organotypic cultures, but were expressed at reduced levels in organotypic cultures with down-regulated Mcl-1. The defect in differentiation marker expression was independent of apoptosis as it could not be rescued by z-VAD. Thus, Mcl-1 serves two important, independent functions in epidermal KCs: acting as a major survival protein by inhibiting premature apoptosis in the spinous and granular layers to promote conification, and promoting the robust induction of KC differentiation markers.

Sitailo, Leonid A.; Jerome-Morais, Anita; Denning, Mitchell F.

2009-01-01

397

Dynamic rewiring of the Drosophila retinal determination network switches its function from selector to differentiation.  

PubMed

Organ development is directed by selector gene networks. Eye development in the fruit fly Drosophila melanogaster is driven by the highly conserved selector gene network referred to as the "retinal determination gene network," composed of approximately 20 factors, whose core comprises twin of eyeless (toy), eyeless (ey), sine oculis (so), dachshund (dac), and eyes absent (eya). These genes encode transcriptional regulators that are each necessary for normal eye development, and sufficient to direct ectopic eye development when misexpressed. While it is well documented that the downstream genes so, eya, and dac are necessary not only during early growth and determination stages but also during the differentiation phase of retinal development, it remains unknown how the retinal determination gene network terminates its functions in determination and begins to promote differentiation. Here, we identify a switch in the regulation of ey by the downstream retinal determination genes, which is essential for the transition from determination to differentiation. We found that central to the transition is a switch from positive regulation of ey transcription to negative regulation and that both types of regulation require so. Our results suggest a model in which the retinal determination gene network is rewired to end the growth and determination stage of eye development and trigger terminal differentiation. We conclude that changes in the regulatory relationships among members of the retinal determination gene network are a driving force for key transitions in retinal development. PMID:24009524

Atkins, Mardelle; Jiang, Yuwei; Sansores-Garcia, Leticia; Jusiak, Barbara; Halder, Georg; Mardon, Graeme

2013-08-29

398

Suppression of AP1 Transcription Factor Function in Keratinocyte Suppresses Differentiation  

PubMed Central

Our previous study shows that inhibiting activator protein one (AP1) transcription factor function in murine epidermis, using dominant-negative c-jun (TAM67), increases cell proliferation and delays differentiation. To understand the mechanism of action, we compare TAM67 impact in mouse epidermis and in cultured normal human keratinocytes. We show that TAM67 localizes in the nucleus where it forms TAM67 homodimers that competitively interact with AP1 transcription factor DNA binding sites to reduce endogenous jun and fos factor binding. Involucrin is a marker of keratinocyte differentiation that is expressed in the suprabasal epidermis and this expression requires AP1 factor interaction at the AP1-5 site in the promoter. TAM67 interacts competitively at this site to reduce involucrin expression. TAM67 also reduces endogenous c-jun, junB and junD mRNA and protein level. Studies with c-jun promoter suggest that this is due to reduced transcription of the c-jun gene. We propose that TAM67 suppresses keratinocyte differentiation by interfering with endogenous AP1 factor binding to regulator elements in differentiation-associated target genes, and by reducing endogenous c-jun factor expression.

Han, Bingshe; Rorke, Ellen A.; Adhikary, Gautam; Chew, Yap Ching; Xu, Wen; Eckert, Richard L.

2012-01-01

399

Human foreskin fibroblast-like stromal cells can differentiate into functional hepatocytic cells.  

PubMed

Foreskin fibroblast-like stromal cells (FDSCs) are progenitors isolated from human tissue that can differentiate into diverse cell types. Many types of stem cells can differentiate into hepatocyte-like cells, which could be used for drug testing or in liver regeneration therapy, but whether FDSCs can be converted into functional hepatocytes is unknown. FDSCs show divergent properties when cultured in distinct media, forming spheres in Dulbecco's modified Eagle's medium (DMEM) containing F12, epidermal growth factor (EGF), and basic fibroblast growth factor (b-FGF), but have fibroblast-like morphology when cultured in DMEM-based growth medium. Both cell populations express the typical mesenchymal stem cell markers CD90, CD105, and CD73, but the p75 neurotrophin receptor (p75NTR) was detected only in FDSC spheres. Both types of FDSCs can differentiate into hepatocyte-like cells, which express typical liver markers, including albumin and hepatocyte paraffin 1 (Hep Par1), along with liver-specific biological activities. When plasmids containing the human hepatitis B virus (HBV) genome were transfected transiently into FDSCs, differentiated hepatocyte-like cells secrete large amounts of HBe and HBs antigens. FDSCs could be used for clinical hepatic therapy and/or serve as a model of HBV. PMID:23956153

Huang, Hsing-I; Chen, Shao-Kuan; Wang, Robert Y-L; Shen, Chia-Rui; Cheng, Yu-Che

2013-09-16

400

Phorbol myristate acetate differentiates human adipose-derived mesenchymal stem cells into functional cardiogenic cells.  

PubMed

To achieve effective regeneration of injured myocardium, it is important to find physiological way of improving the cardiogenic differentiation of stem cells. Previous studies demonstrated that cardiomyocytes from bone marrow-derived mesenchymal stem cells (BMSCs) activated with phorbolmyristate acetate (PMA), a protein kinase C (PKC) activator, restore electromechanical function in infarcted rat hearts. In this study, we investigated the effect of PMA on cardiogenic differentiation of adipose-derived MSCs (ASCs) for clinical applications. To confirm the effect of PMA, ASCs treated with 1?M PMA were grown for nine days. The expression of cardiac-specific markers (cardiac troponin T, myosin light chain, myosin heavy chain) in PMA-treated MSCs was demonstrated by immunocytochemistry. Alhough few ?(1A) receptors exist in ASCs, ?(1)-adrenergic receptor subtypes were preferentially expressed in PMA-treated ASCs. Moreover, expression of the ?-adrenergic and muscarinic receptors increased in PMA-treated ASCs compared to normal cells. The mRNA levels of Ca(2+)-related factors (SERCA 2a; sarcoplasmic reticulum Ca(2+)-ATPase, LTCC; L-type Ca(2+) channel) in treated ASCs were similar to the levels in cardiomyocytes. Following the transplantation of chemically activated cardiogenic ASCs into infarcted myocardium, histological analysis showed that infarct size, interstitial fibrosis, and apoptotic index were markedly decreased and cardiac function was restored. In conclusion, PMA might induce the cardiogenic differentiation of human ASCs as well as BMSCs. This result suggests successful use of human ASCs in cardiac regeneration therapy. PMID:22809507

Chang, Woochul; Lim, Soyeon; Song, Byeong-Wook; Lee, Chang Youn; Park, Moon-Seo; Chung, Young-An; Yoon, Cheesoon; Lee, Se-Yeon; Ham, Onju; Park, Jun-Hee; Choi, Eunhyun; Maeng, Lee-So; Hwang, Ki-Chul

2012-07-15

401

FIDEA: a server for the functional interpretation of differential expression analysis.  

PubMed

The results of differential expression analyses provide scientists with hundreds to thousands of differentially expressed genes that need to be interpreted in light of the biology of the specific system under study. This requires mapping the genes to functional classifications that can be, for example, the KEGG pathways or InterPro families they belong to, their GO Molecular Function, Biological Process or Cellular Component. A statistically significant overrepresentation of one or more category terms in the set of differentially expressed genes is an essential step for the interpretation of the biological significance of the results. Ideally, the analysis should be performed by scientists who are well acquainted with the biological problem, as they have a wealth of knowledge about the system and can, more easily than a bioinformatician, discover less obvious and, therefore, more interesting relationships. To allow experimentalists to explore their data in an easy and at the same time exhaustive fashion within a single tool and to test their hypothesis quickly and effortlessly, we developed FIDEA. The FIDEA server is located at http://www.biocomputing.it/fidea; it is free and open to all users, and there is no login requirement. PMID:23754850

D'Andrea, Daniel; Grassi, Luigi; Mazzapioda, Mariagiovanna; Tramontano, Anna

2013-06-10

402

HIF-2? downregulation in the absence of functional VHL is not sufficient for renal cell differentiation  

PubMed Central

Background Mutational inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene has been linked to hereditary as well as sporadic clear cell renal carcinomas. The product of the VHL gene, pVHL, acts to target hypoxia-inducible factor alpha (HIF-?) subunits for ubiquitination and subsequent degradation. Using an RNA interference approach to lower levels of HIF-2? in two different renal cell lines that lack functional pVHL, we have tested the contribution of HIF-2? toward cellular pVHL activities. Results Knockdown of HIF-2? resulted in cell cycle arrest of renal cells that were grown on collagen I, indicating that this pVHL function is dependent on HIF-2? regulation. However, cellular morphological changes and downregulation of integrins ?5 and ?1, which were seen upon pVHL replacement, were not faithfully phenocopied by HIF-2? reduction. Moreover, fibronectin deposition and expression of renal cell differentiation markers were observed in cells containing replaced pVHL, but not in HIF-2? knockdown cells, indicating that these pVHL functions may occur independently of HIF-2? downregulation. Conclusion These results indicate that HIF-2? regulation is not sufficient for pVHL-induced renal cell differentiation. We hypothesize that in addition to HIF-2? dysregulation, abrogation of additional pVHL functions is required for the initiation of renal carcinogenesis.

Hughes, Michael D; Kapllani, Erilda; Alexander, Ashlynn E; Burk, Robert D; Schoenfeld, Alan R

2007-01-01

403

Differential subcellular distributions and trafficking functions of hnRNP A2/B1 spliceoforms  

PubMed Central

Trafficking of mRNA molecules from the nucleus to distal processes in neural cells is mediated by hnRNP A2/B1 trans-acting factors. Although hnRNP A2/B1 is alternatively spliced to generate 4 isoforms, most functional studies have not distinguished among these isoforms. Here we show, using isoform-specific antibodies and isoform-specific GFP-fusion expression constructs, that A2b is the predominant cytoplasmic isoform in neural cells, suggesting that it may play a key role in mRNA trafficking. The differential subcellular distribution patterns of the individual isoforms are determined by the presence or absence of alternative exons that also affect their dynamic behavior in different cellular compartments, as measured by fluorescence correlation spectroscopy. Expression of A2b is also differentially regulated with age, species and cellular development. Furthermore, co-injection of isoform-specific antibodies and labeled RNA into live oligodendrocytes shows that assembly of RNA granules is impaired by blockade of A2b function. These findings suggest that neural cells modulate mRNA trafficking by regulating alternative splicing of hnRNP A2/B1 and controlling expression levels of A2b, which may be the predominant mediator of cytoplasmic trafficking functions. These findings highlight the importance of considering isoform-specific functions for alternatively spliced proteins.

Han, Siew Ping; Friend, Lexie R.; Carson, John H.; Korza, George; Barbarese, Elisa; Maggipinto, Michael; Hatfield, Jodie T.; Rothnagel, Joseph A.; Smith, Ross

2010-01-01

404

VPAC receptors: structure, molecular pharmacology and interaction with accessory proteins  

PubMed Central

The vasoactive intestinal peptide (VIP) is a neuropeptide with wide distribution in both central and peripheral nervous systems, where it plays important regulatory role in many physiological processes. VIP displays a large biological functions including regulation of exocrine secretions, hormone release, fetal development, immune responses, etc. VIP appears to exert beneficial effect in neuro-degenerative and inflammatory diseases. The mechanism of action of VIP implicates two subtypes of receptors (VPAC1 and VPAC2), which are members of class B receptors belonging to the super-family of GPCR. This article reviews the current knowledge regarding the structure and molecular pharmacology of VPAC receptors. The structure–function relationship of VPAC1 receptor has been extensively studied, allowing to understand the molecular basis for receptor affinity, specificity, desensitization and coupling to adenylyl cyclase. Those studies have clearly demonstrated the crucial role of the N-terminal ectodomain (N-ted) of VPAC1 receptor in VIP recognition. By using different approaches including directed mutagenesis, photoaffinity labelling, NMR, molecular modelling and molecular dynamic simulation, it has been shown that the VIP molecule interacts with the N-ted of VPAC1 receptor, which is itself structured as a ‘Sushi’ domain. VPAC1 receptor also interacts with a few accessory proteins that play a role in cell signalling of receptors. Recent advances in the structural characterization of VPAC receptor and more generally of class B GPCRs will lead to the design of new molecules, which could have considerable interest for the treatment of inflammatory and neuro-degenerative diseases. LINKED ARTICLES This article is part of a themed section on Secretin Family (Class B) G Protein-Coupled Receptors. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.166.issue-1

Couvineau, Alain; Laburthe, Marc

2012-01-01

405

Differential Item Functioning Related to Age in the Reading Subtest of the Test of Functional Health Literacy in Adults  

PubMed Central

Differential item functioning (DIF) occurs when items in a measure perform in ways that are different for members of a target group when the different performance is not related to the individual's overall ability to be assessed. DIF may arise for a number of reasons but is often evaluated in order to ensure that tests and measures are fair evaluations of a group's abilities. Based on observations when administering the test, we developed the hypothesis that some items on the reading comprehension subtest of the Test of Functional Health Literacy (TOFHLA) might be differentially more difficult for older adults and the elderly due to its use of the cloze response format, in which the participant is required to determine what word, when placed in a blank space in a sentence, will ensure that the sentence is intelligible. Others have suggested that the cloze response format may make demands on verbal fluency, an ability that is reduced with the increasing age. Our analyses show that age-related DIF may present in a nearly one-half of reading comprehension items of the TOFHLA. Results of this measure in older persons should be interpreted cautiously.

Ownby, Raymond L.; Waldrop-Valverde, Drenna

2013-01-01

406

Axillary accessory breast associated with galactorrhea in an adolescent girl  

PubMed Central

We present herein a case of right axillary accessory breast associated with galactorrhea in an adolescent girl. A 14-year-old Japanese girl presented with an 11-month history of a tender, subcutaneous lesion in the right axillary fossa. Seven months later, she experienced menarche. Subsequently, the patient noticed pressure-induced galactorrhea from both nipples. Physical examination revealed an elastic, firm and well-demarcated subcutaneous tumor 3 × 2 cm in size. A biopsy specimen showed proliferation of mammary gland tissue in the stroma located below the subcutaneous fat tissue. On the basis of these findings the patient was diagnosed with an accessory breast. Interestingly, the galactorrhea ceased after surgical removal of the accessory breast.

Kyo, Akemi; Sasaki, Yoshihito; Fukunaga, Atsushi; Nagano, Tohru; Funasaka, Yoko; Nishigori, Chikako

2010-01-01

407

Multi-voxel Patterns Reveal Functionally Differentiated Networks Underlying Auditory Feedback Processing of Speech  

PubMed Central

The everyday act of speaking involves the complex processes of speech motor control. An important component of control is monitoring, detection and processing of errors when auditory feedback does not correspond to the intended motor gesture. Here we show, using fMRI and converging operations within a multi-voxel pattern analysis framework, that this sensorimotor process is supported by functionally differentiated brain networks. During scanning, a real-time speech-tracking system was employed to deliver two acoustically different types of distorted auditory feedback or unaltered feedback while human participants were vocalizing monosyllabic words, and to present the same auditory stimuli while participants were passively listening. Whole-brain analysis of neural-pattern similarity revealed three functional networks that were differentially sensitive to distorted auditory feedback during vocalization, compared to during passive listening. One network of regions appears to encode an ‘error signal’ irrespective of acoustic features of the error: this network, including right angular gyrus, right supplementary motor area, and bilateral cerebellum, yielded consistent neural patterns across acoustically different, distorted feedback types, only during articulation (not during passive listening). In contrast, a fronto-temporal network appears sensitive to the speech features of auditory stimuli during passive listening; this preference for speech features was diminished when the same stimuli were presented as auditory concomitants of vocalization. A third network, showing a distinct functional pattern from the other two, appears to capture aspects of both neural response profiles. Taken together, our findings suggest that auditory feedback processing during speech motor control may rely on multiple, interactive, functionally differentiated neural systems.

Zheng, Zane Z.; Vicente-Grabovetsky, Alejandro; MacDonald, Ewen N.; Munhall, Kevin G.; Cusack, Rhodri; Johnsrude, Ingrid S.

2013-01-01

408

Physical mapping of a functional cluster of epidermal differentiation genes on chromosome 1q21  

SciTech Connect

Genes of three protein families, which are in part specifically expressed in the course of terminal differentiation of human epidermis, have previously been mapped to chromosome 1q21. Here, the authors show that these genes are physically linked within 2.05 Mb of DNA. The order is calpactin I light chain, trichohyalin, profilaggrin, involucrin/small proline-rich protein, loricrin, and calcyclin. The colocalization in the 1q21 region together with their functional interdependence during epidermal differentiation raises the question whether these genes share regulatory elements which control their transcriptional activities. As several of them are potential candidate genes for dyskeratotic skin diseases, this physical map should be of great value for genetic linkage analyses. 55 refs., 3 figs., 1 tab.

Volz, A.; Ziegler, A.; Mischke, D. (Freie Universitaet Berlin (Germany)); Korge, B.P.; Compton, J.G.; Steinert, P.M. (NIAMS, Bethesda, MD (United States))

1993-10-01

409

Effect of RGD functionalization and stiffness modulation of polyelectrolyte multilayer films on muscle cell differentiation.  

PubMed

Skeletal muscle tissue engineering holds promise for the replacement of muscle damaged by injury and for the treatment of muscle diseases. Although arginylglycylaspartic acid (RGD) substrates have been widely explored in tissue engineering, there have been no studies aimed at investigating the combined effects of RGD nanoscale presentation and matrix stiffness on myogenesis. In the present work we use polyelectrolyte multilayer films made of poly(L-lysine) (PLL) and poly(L-glutamic) acid (PGA) as substrates of tunable stiffness that can be functionalized by a RGD adhesive peptide to investigate important events in myogenesis, including adhesion, migration, proliferation and differentiation. C2C12 myoblasts were used as cellular models. RGD presentation on soft films and increasing film stiffness could both induce cell adhesion, but the integrins involved in adhesion were different in the case of soft and stiff films. Soft films with RGD peptide appeared to be the most appropriate substrate for myogenic differentiation, while the stiff PLL/PGA films induced significant cell migration and proliferation and inhibited myogenic differentiation. ROCK kinase was found to be involved in the myoblast response to the different films. Indeed, its inhibition was sufficient to rescue differentiation on stiff films, but no significant changes were observed on stiff films with the RGD peptide. These results suggest that different signaling pathways may be activated depending on the mechanical and biochemical properties of multilayer films. This study emphasizes the advantage of soft PLL/PGA films presenting the RGD peptide in terms of myogenic differentiation. This soft RGD-presenting film may be further used as a coating of various polymeric scaffolds for muscle tissue engineering. PMID:23261924

Gribova, Varvara; Gauthier-Rouvière, Cécile; Albigès-Rizo, Corinne; Auzely-Velty, Rachel; Picart, Catherine

2012-12-20

410

Establishment of Irreversible Growth Arrest in Myogenic Differentiation Requires the RB LXCXE-Binding Function  

PubMed Central

The crystal structure of the A-B domain of RB has defined the binding pocket for the LXCXE peptide motif. Using the crystal structure as a guide, we have inactivated the LXCXE-binding pocket by replacing N757 with Phe [to obtain RB(N757F)]. RB(N757F) does not bind to viral oncoproteins but retains the ability to bind and inhibit E2F. RB(N757F) is less effective than the wild-type RB [RB(WT)] in repressing E2F-regulated transcription, and its repression activity is not affected by trichostatin A, an inhibitor of histone deacetylases. However, RB(N757F) is as effective as RB(WT) in suppressing cell growth. Interestingly, RB(N757F) cannot establish an irreversible growth arrest in differentiated myocytes. Differentiated myocytes with RB(WT) become refractory to serum. By contrast, differentiated myocytes with RB(N757F) undergo DNA synthesis and phosphorylate RB(N757F) in response to serum, despite a high level of p21Cip1 expression. Mutation of the phosphorylation sites in RB(N757F) rescued its defect and allowed myocytes to permanently withdraw from the cell cycle. These results demonstrate that it is possible to inactivate the LXCXE-binding pocket without compromising the overall integrity of RB. Moreover, the LXCXE-binding pocket is dispensable for the intrinsic growth suppression function of RB. However, the LXCXE-binding function is essential for RB to establish the serum-refractory state in differentiated myocytes.

Chen, Tung-Ti; Wang, Jean Y. J.

2000-01-01

411

Notch gain of function inhibits chondrocyte differentiation via Rbpj-dependent suppression of Sox9  

PubMed Central

Abstract Notch signaling plays a critical role during development by directing the binary cell fate decision between progenitors and differentiated cells. Previous studies have shown sustained Notch activation in cartilage leads to chondrodysplasia. Genetic evidence indicates that Notch regulates limb bud mesenchymal stem cell differentiation into chondrocytes via an Rbpj-dependent Notch pathway. However, it is still unknown how Notch governs chondrogenesis in the axial skeleton where Notch serves a primary patterning function. We hypothesized that both Rbpj-dependent and Rbpj-independent Notch signaling mechanisms might be involved. Cartilage-specific Notch gain-of-function (GOF) mutant mice display chondrodysplasia accompanied by loss of Sox9 expression in vertebrae. To evaluate the contribution of an Rbpj-dependent Notch signaling to this phenotype, we deleted Rbpj on the Notch GOF background. These mice showed persistent spine abnormalities characterized by “butterfly” vertebrae suggesting that removal of Rbpj does not fully rescue the axial skeleton deformities caused by Notch GOF. However, Sox9 protein level was restored in Rbpj-deficient Notch GOF mice compared with Notch GOF mutants, demonstrating that regulation of Sox9 expression is canonical or Rbpj-dependent. To further understand the molecular basis of this regulation, we performed chromatin immunoprecipitation (ChIP) assays and detected the recruitment of the Rbpj/NICD transcription complex to Rbpj-binding sites upstream of the Sox9 promoter. The association of the Rbpj/NICD complex with the Sox9 promoter is associated with transcriptional repression of Sox9 in a cellular model of chondrocyte differentiation. Hence, Notch negatively regulates chondrocyte differentiation in the axial skeleton by suppressing Sox9 transcription, and Rbpj-independent Notch signaling mechanisms may also contribute to axial skeletogenesis.

Chen, Shan; Tao, Jianning; Bae, Yangjin; Jiang, Ming-Ming; Bertin, Terry; Chen, Yuqing; Yang, Tao; Lee, Brendan

2013-01-01

412

Redundant functions of B-Myb and c-Myb in differentiating myeloid cells.  

PubMed

We show in this report that the human myeloid leukemia cell line GFD8 is a useful model to compare the biological function of the structurally related c-Myb and B-Myb proto-oncogenes and to investigate the c-myb domains required for this function. GFD8 cells are dependent for growth on granulocyte-macrophage colony-stimulating factor and differentiate in response to phorbol myristate acetate (PMA). We have stably transfected this cell line with constructs constitutively expressing c-Myb or B-Myb. Deregulated expression of both c-Myb and B-Myb inhibited the differentiation observed in response to PMA and, in particular, the induction of the CD11b and CD11c antigens on the cell surface, and the induction of adherence. Furthermore, c-Myb and B-Myb enhanced expression of CD13 upon PMA treatment. Although deregulated Myb expression did not alter the growth factor dependence of the cells, it led to an increase in G2 relative to G1 arrest in cells induced to differentiate in response to PMA, whereas control vector-transfected cells were blocked mostly in G1. This decrease in G1 block took place despite normal induction of the cyclin-dependent kinase inhibitor protein p21 (CIP1/WAF1). Thus, GFD8 cells stably expressing the human B-Myb protein behaved in a manner indistinguishable from those stably expressing C-Myb for both differentiation and cell cycle parameters. In agreement with these findings and differently from most previous reports, transactivation assays show that B-myb can indeed act as a strong activator of transcription. Finally, we demonstrated that although the DNA-binding domain of c-myb is required for both the differentiation block and the shift in cell cycle after PMA treatment, phosphorylation by casein kinase II and mitogen-activated protein kinase at positions 11 and 12 or 532 of c-myb, respectively, are not. We conclude that c-Myb and B-Myb may activate a common cellular program in the GFD8 cell line involved in both differentiation and cell cycle control. PMID:9419419

Golay, J; Broccoli, V; Borleri, G M; Erba, E; Faretta, M; Basilico, L; Ying, G G; Piccinini, G; Shapiro, L H; Lovri?, J; Nawrath, M; Mölling, K; Rambaldi, A; Introna, M

1997-12-01

413

[Application of the new diagnostic tests for vertigo : Differentiated analysis of vestibular function].  

PubMed

Due to the development of new methods such as the vestibular evoked myogenic potential and the video head impulse tests, clinical vestibular diagnostic procedures are currently in an era of change. The spectrum of available techniques renders a specific, quantitative and objective analysis of vestibular reflexes possible for the first time. Moreover, a combination of different methods permits the assessment of different functional areas of the vestibular receptor. In addition to a topological diagnosis, the concept of a differentiated analysis of vestibular receptor function includes evaluation of frequency-specific functional areas (dynamic frequency analysis) and monitoring of temporal changes (time-dependent diagnostics). Consequently, the overall outcome of physiological tests can be viewed from a new perspective. This enables a comprehensive assessment of vestibulopathies in clinical practice and furthers the understanding of these disorders. PMID:23913192

Walther, L E

2013-09-01

414

The differential influence of contextual risks on psychosocial functioning and participation of Australian aboriginal youth.  

PubMed

This study investigated the differential influence of contextual risks for positive psychosocial functioning and participation in education or employment in a representative sample of 12- to 17-year-old Aboriginal youth (N = 674) using data drawn from the Western Australian Aboriginal Child Health Survey (WAACHS) 2000-2002. The authors modeled the influence of 3 empirical risk measures (risk factor, cumulative risk, and single risks) on positive psychosocial functioning and participation in education or employment. Results showed different risks for different developmental outcomes. Single sociodemographic risks were associated with reduced likelihood of positive psychosocial functioning, whereas cumulative risk and composite Family Health and Community Risk measures were associated with reduced likelihood of participation in education or employment. Methodological issues and implications for interventions to support young Aboriginal people's adaptation are discussed. PMID:24164518

Hopkins, Katrina D; Taylor, Catherine L; Zubrick, Stephen R

2013-10-01

415

An Accessory Muscle of Pectoral Region: A Case Report  

PubMed Central

Among the variations of pectoral muscles, this case appears to be unique in the literature. This was a case of an accessory pectoral muscle which was located between pectoralis major and pectoralis minor muscles, which was discovered during a routine anatomy dissection. The accessory muscle originated from 6th and 7th ribs at costo-chondral junction, which travelled supero-laterally and inserted by fusing with fibres of pectoralis minor. This unusual muscle holds importance for surgeons while they perform dissectomies, in avoiding complications.

Bannur, B.M.; Mallashetty, Nagaraj; Endigeri, Preetish

2013-01-01

416

[Bilateral coronary-pulmonary artery fistula and accessory vascular connection of the thoracic aorta to the right lower pulmonary artery].  

PubMed

A 41-year-old man presenting with atypical chest pain was admitted to hospital with suspected pericarditis after a common cold disease. A complex risk profile for arteriosclerotic coronary artery disease was taken into account in differential diagnosis. Cardiac catheterization revealed large bilateral coronary artery-pulmonary artery fistulas as well as an accessory vessel with origin of the thoracic aorta both draining into the lower right pulmonary artery. The vessel anomalies showed a remarkable plexus-like morphology before entering into the pulmonary artery. Arteriosclerotic coronary artery disease was not found. No evidence of myocardial ischemia was found in the furthermore asymptomatic patient, therefore surgical correction of the vessel anomalies was not performed. To our knowledge the present case report represents the first case with bilateral coronary artery-pulmonary artery fistulas and an accessory communication of the thoracic aorta to the pulmonary artery vasculature. PMID:8147055

Krüger, D; Wiegand, U; Potratz, J; Stierle, U; Sheikhzadeh, A

1993-12-01

417

75 FR 41523 - Paris Accessories, Inc., Including On-Site Leased Workers From Job Connections, New Smithville...  

Federal Register 2010, 2011, 2012, 2013

...TA-W-71,106; TA-W-71,106A] Paris Accessories, Inc., Including On-Site...Job Connections, New Smithville, PA; Paris Accessories, Inc., Allentown, PA...Reconsideration applicable to workers of Paris Accessories, Inc., including...

2010-07-16

418

75 FR 34180 - Paris Accessories, Inc., Including On-Site Leased Workers From Job Connections, New Smithsville...  

Federal Register 2010, 2011, 2012, 2013

...Training Administration [TA-W-71,106] Paris Accessories, Inc., Including On-Site...reconsideration, I determine that workers of Paris Accessories, Inc., New Smithsville...following certification: All workers of Paris Accessories, Inc., New...

2010-06-16

419

A Monte Carlo investigation of the likelihood-ratio procedure in the detection of differential item functioning  

Microsoft Academic Search

When items in an educational or psychological measurement instrument perform differentially in two or more groups of examinees, the ability of that measuring device to accurately measure the intended construct is negatively impacted. As a result, differential item functioning (DIF) contributes to test invalidity.^ The likelihood ratio (LR) procedure for detecting DIF in educational and psychological measurements, has been largely

Kevin P Sweeney

1997-01-01

420

Existence and uniqueness of pseudo almost periodic solutions to some abstract partial neutral functional-differential equations and applications  

NASA Astrophysics Data System (ADS)

The paper considers the existence and uniqueness of pseudo almost periodic (mild) solutions to some classes of first-order partial neutral functional-differential equations. Upon making some suitable assumptions, existence and uniqueness results are obtained. Applications include both a partial integro-differential equation arising in control systems and the scalar reaction-diffusion equation with delay.

Diagana, Toka; Hernandez, Eduardo M.

2007-03-01

421

Explicitly Correlated Gaussian Basis Functions: Derivation and Implementation of Matrix Elements and Gradient Formulas Using Matrix Differential Calculus  

Microsoft Academic Search

The matrix differential calculus is introduced to the quantum chemistry community via new matrix derivations of integral formulas and gradients for Hamiltonian matrix elements in a basis of correlated Gaussian functions. Requisite mathematical background material on Kronecker products, Hadamard products, the vec and vech operators, linear structures, and matrix differential calculus is presented. New matrix forms for the kinetic and

Donald Bruce Kinghorn

1995-01-01

422

Heparin functionalized PEG gels that modulate protein adsorption for hMSC adhesion and differentiation.  

PubMed

Heparin was modified with methacrylate groups, copolymerized with dimethacrylated poly(ethylene glycol), and analyzed as a localized delivery vehicle for bFGF and synthetic extracellular matrix for the differentiation of hMSCs. By deriving cues from molecules normally present in the extracellular matrix (ECM), a complex network of collagens, laminin, fibronectin, glycosaminoglycans, and growth factors, synthetic cell scaffolds can be designed that actively sequester important bioactive signals. Among the glycosaminoglycans, heparin binds reversibly with many proteins, therefore, poly(ethylene glycol) based biomaterials, normally resistant to cell adhesion, functionalized with heparin in order to sequester important proteins, can actively and selectively stimulate desired cell functions. Results demonstrate that methacrylate-modified heparin retained its ability to bind heparin-binding proteins both in solution and when copolymerized with dimethacrylated PEG in a hydrogel. In addition, the heparin functionalized gels can deliver biologically active bFGF for up to 5 weeks. Finally, the gels were examined as a potential scaffold for hMSC culture and were found to promote adhesion, proliferation, and osteogenic differentiation. PMID:16701827

Benoit, Danielle S W; Anseth, Kristi S

2005-04-26

423

MYC2 Differentially Modulates Diverse Jasmonate-Dependent Functions in Arabidopsis[W  

PubMed Central

The Arabidopsis thaliana basic helix-loop-helix Leu zipper transcription factor (TF) MYC2/JIN1 differentially regulates jasmonate (JA)-responsive pathogen defense (e.g., PDF1.2) and wound response (e.g., VSP) genes. In this study, genome-wide transcriptional profiling of wild type and mutant myc2/jin1 plants followed by functional analyses has revealed new roles for MYC2 in the modulation of diverse JA functions. We found that MYC2 negatively regulates Trp and Trp-derived secondary metabolism such as indole glucosinolate biosynthesis during JA signaling. Furthermore, MYC2 positively regulates JA-mediated resistance to insect pests, such as Helicoverpa armigera, and tolerance to oxidative stress, possibly via enhanced ascorbate redox cycling and flavonoid biosynthesis. Analyses of MYC2 cis binding elements and expression of MYC2-regulated genes in T-DNA insertion lines of a subset of MYC2–regulated TFs suggested that MYC2 might modulate JA responses via differential regulation of an intermediate spectrum of TFs with activating or repressing roles in JA signaling. MYC2 also negatively regulates its own expression, and this may be one of the mechanisms used in fine-tuning JA signaling. Overall, these results provide new insights into the function of MYC2 and the transcriptional coordination of the JA signaling pathway.

Dombrecht, Bruno; Xue, Gang Ping; Sprague, Susan J.; Kirkegaard, John A.; Ross, John J.; Reid, James B.; Fitt, Gary P.; Sewelam, Nasser; Schenk, Peer M.; Manners, John M.; Kazan, Kemal

2007-01-01

424

Functional and phenotypic relevance of differentially expressed proteins in calcineurin mutants of Caenorhabditis elegans.  

PubMed

Calcineurin is a heterodimeric serine/threonine protein phosphatase, important for many cellular processes such as T-cell regulation, cardiac hypertrophy and kidney development. We previously reported the characterization of Caenorhabditis elegans calcineurin mutants as providing a simple but excellent genetic model system for studying in vivo functions of calcineurin. Calcineurin loss-of-function mutants, cnb-1(lf), and gain-of-function mutants, tax-6(gf), show certain opposite phenotypes as well as some similar phenotypes. In order to explain the phenotypic similarity observed in both loss-of-function and gain-of-function mutants, we examined the proteins that followed similar trends in both mutants relative to wild-type worms by using 2-DE. Interestingly, VHA-13, HSP-6 and phosphoenolpyruvate carboxykinase are down-regulated in both mutants. A total of 96 differentially regulated proteins were identified by MALDI-TOF/MS. Among these, 42 proteins are up-regulated and 54 proteins are down-regulated in calcineurin mutants. Furthermore, knock-down of about 30% of the genes, which are down-regulated in calcineurin mutants, showed some of the phenotypes of calcineurin-null mutants. This analysis suggests the functional relevance of these proteins to calcineurin activity in C. elegans. PMID:16402360

Ahn, Do-Hwan; Singaravelu, Gunasekaran; Lee, Sooung; Ahnn, Joohong; Shim, Yhong-Hee

2006-02-01

425

Differentiation Rules: Implicit Differentiation  

NSDL National Science Digital Library

This resource introduces that some curves cannot easily be represented as explicit functions of a single variable. In this case, one can use the method of implicit differentiation to determine the derivatives of inverse trigonometric functions.

Freeze, Michael

2003-01-22

426

New Advances on the Functions of Epidermal Growth Factor Receptor and Ceramides in Skin Cell Differentiation, Disorders and Cancers  

Microsoft Academic Search

Recent advances in understanding of the biological functions of the epidermal growth factor and epidermal growth factor receptor (EGF-EGFR) system and ceramide production for the maintenance of skin integrity and barrier function are reported. In particular, the opposite roles of EGFR and ceramide cascades in epithelial keratinocyte proliferation, migration and terminal differentiation are described. Moreover, the functions of ceramides in

M. Mimeault; D. Bonenfant; S. K. Batra

2004-01-01

427

21 CFR 884.4150 - Bipolar endoscopic coagulator-cutter and accessories.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Bipolar endoscopic coagulator-cutter and accessories...Gynecological Surgical Devices § 884.4150 Bipolar endoscopic coagulator-cutter and accessories. (a) Identification. A bipolar endoscopic...

2009-04-01

428

21 CFR 884.4150 - Bipolar endoscopic coagulator-cutter and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Bipolar endoscopic coagulator-cutter and accessories...Gynecological Surgical Devices § 884.4150 Bipolar endoscopic coagulator-cutter and accessories. (a) Identification. A bipolar endoscopic...

2010-04-01

429

49 CFR 178.255-7 - Protection of valves and accessories.  

Code of Federal Regulations, 2012 CFR

... PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...Tanks § 178.255-7 Protection of valves and accessories. (a) All valves, fittings, accessories, safety devices, gauging devices, and...

2012-10-01

430

21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.  

Code of Federal Regulations, 2013 CFR

...AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6190 Assisted... (a) Identification. Assisted reproduction microscopes and microscope accessories...which are classified under assisted reproduction accessories) are optical...

2013-04-01

431

21 CFR 884.1300 - Uterotubal carbon dioxide insufflator and accessories.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Uterotubal carbon dioxide insufflator and accessories...Devices § 884.1300 Uterotubal carbon dioxide insufflator and accessories...Identification. A uterotubal carbon dioxide insufflator and...

2013-04-01

432

22 CFR 121.8 - End-items, components, accessories, attachments, parts, firmware, software and systems.  

Code of Federal Regulations, 2013 CFR

...accessories, attachments, parts, firmware, software and systems. 121.8 Section 121...accessories, attachments, parts, firmware, software and systems. (a) An end-item...is not limited to circuits into which software has been programmed. (f)...

2013-04-01

433

Mutational Signatures of De-Differentiation in Functional Non-Coding Regions of Melanoma Genomes  

PubMed Central

Much emphasis has been placed on the identification, functional characterization, and therapeutic potential of somatic variants in tumor genomes. However, the majority of somatic variants lie outside coding regions and their role in cancer progression remains to be determined. In order to establish a system to test the functional importance of non-coding somatic variants in cancer, we created a low-passage cell culture of a metastatic melanoma tumor sample. As a foundation for interpreting functional assays, we performed whole-genome sequencing and analysis of this cell culture, the metastatic tumor from which it was derived, and the patient-matched normal genomes. When comparing somatic mutations identified in the cell culture and tissue genomes, we observe concordance at the majority of single nucleotide variants, whereas copy number changes are more variable. To understand the functional impact of non-coding somatic variation, we leveraged functional data generated by the ENCODE Project Consortium. We analyzed regulatory regions derived from multiple different cell types and found that melanocyte-specific regions are among the most depleted for somatic mutation accumulation. Significant depletion in other cell types suggests the metastatic melanoma cells de-differentiated to a more basal regulatory state. Experimental identification of genome-wide regulatory sites in two different melanoma samples supports this observation. Together, these results show that mutation accumulation in metastatic melanoma is nonrandom across the genome and that a de-differentiated regulatory architecture is common among different samples. Our findings enable identification of the underlying genetic components of melanoma and define the differences between a tissue-derived tumor sample and the cell culture created from it. Such information helps establish a broader mechanistic understanding of the linkage between non-coding genomic variations and the cellular evolution of cancer.

Parker, Stephen C. J.; Gartner, Jared; Cardenas-Navia, Isabel; Wei, Xiaomu; Ozel Abaan, Hatice; Ajay, Subramanian S.; Hansen, Nancy F.; Song, Lingyun; Bhanot, Umesh K.; Killian, J. Keith; Gindin, Yevgeniy; Walker, Robert L.; Meltzer, Paul S.; Mullikin, James C.; Furey, Terrence S.; Crawford, Gregory E.; Rosenberg, Steven A.; Samuels, Yardena; Margulies, Elliott H.

2012-01-01

434

Formas Normais e Dinamica Local de Equacoes Diferenciais Funcionais (Normal Forms and Local Dynamics of Functional Differential Equations).  

National Technical Information Service (NTIS)

The thesis addresses the direct computation of normal forms for retarded Functional Differential Equations (FDEs), associated with the flow on finite dimensional invariant (namely, center) manifolds, in the neighborhood of equilibrium points. The coeffici...

M. T. F. da Paz Pereifa

1992-01-01

435

Role of epidermis-type lipoxygenases for skin barrier function and adipocyte differentiation.  

PubMed

12R-lipoxygenase (12R-LOX) and epidermis-type LOX-3 (eLOX-3) are novel members of the multigene family of mammalian LOX. A considerable gap exists between the identification of these enzymes and their biologic function. Here, we present evidence that 12R-LOX and eLOX-3, acting in sequence, and eLOX-3 in combination with another, not yet identified LOX are critically involved in terminal differentiation of keratinocytes and adipocytes, respectively. Mutational inactivation of 12R-LOX and/or eLOX-3 has been found to be associated with development of an inherited ichthyosiform skin disorder in humans and genetic ablation of 12R-LOX causes a severe impairment of the epidermal lipid barrier in mice leading to post-natal death of the animals. In preadipocytes, a LOX-dependent PPARgamma activating ligand is released into the cell supernatant early upon induction of differentiation and available evidence indicates that this ligand is an eLOX-3-derived product. In accordance with this data is the observation that forced expression of eLOX-3 enhances adipocyte differentiation. PMID:17164140

Fürstenberger, Gerhard; Epp, Nikolas; Eckl, Katja-Martina; Hennies, Hans Christian; Jørgensen, Claus; Hallenborg, Philip; Kristiansen, Karsten; Krieg, Peter

2006-07-24

436

Osteocalcin, a marker of differentiated function during calcification of cultured chick osteoblasts  

SciTech Connect

The expression of differentiated function was examined in cultured osteoblasts isolated from 17-day embryonic chicken calvarie. Cell cultures grown in the absence (control) or presence of 10 mM ..beta..-Glycerol Phosphate (..beta..GP) (stimulus for calcification) were analyzed at 6-day intervals over a 30-day period for total mineral, alkaline phosphatase (AP) activity, osteocalcin levels and collagen. AP was first detected in both cultures between days 6 and 9 when cells became crowded. Control cultures maintained high levels of enzyme activity (30-50 fold) while ..beta.. GPO/sub 4/ culture activity declined after day 18 when extensive mineralization occurred. Osteocalcin, the vitamin K-dependent, bone-specific, calcium-binding protein showed a similar pattern of induction as AP with at 50-100-fold increase in both cultures. Collagen accumulated through out the 30-day experimental period for both ..beta.. GPO/sub 4/ and control cultures while collagen synthesis (/sup 3/H-proline pulse) peaked at day 15 in culture. These results suggest that with time in culture, osteoblast differentiation may be occurring. The increased mineralization of ..beta.. GPO/sub 4/ cultures appeared to down regulate the enzyme activity of AP in comparison to control culture, while osteocalcin synthesis was enhanced. In conclusion, the chick osteoblast system offers a model to study bone cell differentiation, protein synthesis and matrix calcification.

Lian, J.; Chipman, S.; Glowacki, J.; Gerstenfeld, L.

1986-05-01

437

Sox3 Functions in a Cell-Autonomous Manner to Regulate Spermatogonial Differentiation in Mice  

PubMed Central

The X-linked Sox3 gene encodes a member of the Sry high-mobility group box proteins, which play a role in many developmental processes including neurogenesis and testis development. This study further examined the role of Sox3 in spermatogenesis. Males without Sox3 expression exhibited a similar number of germ cell nuclear antigen-positive germ cells at 1, 5, and 10 d postpartum (dpp) compared to their wild-type littermates, but there was significant germ cell depletion by 20 dpp. However, spermatogenesis later resumed and postmeiotic germ cells were observed by 56 dpp. The VasaCre transgene was used to generate a germ cell-specific deletion of Sox3. The phenotype of the germ cell-specific Sox3 knockout was similar to the ubiquitous knockout, indicating an intrinsic role for Sox3 in germ cells. The residual germ cells in 20 dpp Sox3?/Y males were spermatogonia as indicated by their expression of neurogenin3 but not synaptonemal complex protein 3, which is expressed within cells undergoing meiosis. RNA expression analyses corroborated the histological analyses and revealed a gradual transition from relatively increased expression of spermatogonia genes at 20 dpp to near normal expression of genes characteristic of undifferentiated and meiotic germ cells by 84 dpp. Fluorescent-activated cell sorting of undifferentiated (ret tyrosine kinase receptor positive) and differentiated (kit receptor tyrosine kinase-positive) spermatogonia revealed depletion of differentiated spermatogonia in Sox3?/Y tubules. These results indicate that Sox3 functions in an intrinsic manner to promote differentiation of spermatogonia in prepubertal mice but it is not required for ongoing spermatogenesis in adults. The Sox3?/Y males provide a unique model for studying the mechanism of germ cell differentiation in prepubertal testes.

Laronda, Monica M.

2011-01-01

438

Functional Relationships between Genes Associated with Differentiation Potential of Aged Myogenic Progenitors  

PubMed Central

Aging is accompanied by considerable heterogeneity with possible co-expression of differentiation pathways. The present study investigates the interplay between crucial myogenic, adipogenic, and Wnt-related genes orchestrating aged myogenic progenitor differentiation (AMPD) using clonal gene expression profiling in conjunction with Bayesian structure learning (BSL) techniques. The expression of three myogenic regulatory factor genes (Myogenin, Myf-5, MyoD1), four genes involved in regulating adipogenic potential (C/EBP?, DDIT3, FoxC2, PPAR?), and two genes in the Wnt signaling pathway (Lrp5, Wnt5a) known to influence both differentiation programs were determined across 34 clones by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Three control genes were used for normalization of the clonal expression data (18S, GAPDH, and B2M). Constraint-based BSL techniques, namely (a) PC Algorithm, (b) Grow-shrink (GS) algorithm, and (c) Incremental Association Markov Blanket (IAMB) were used to model the functional relationships (FRs) in the form of acyclic networks from the clonal expression profiles. A novel resampling approach that obviates the need for a user-defined confidence threshold is proposed to identify statistically significant FRs at small sample sizes. Interestingly, the resulting acyclic network consisted of FRs corresponding to myogenic, adipogenic, Wnt-related genes and their interaction. A significant number of these FRs were robust to normalization across the three house-keeping genes and the choice of the BSL technique. The results presented elucidate the delicate balance between differentiation pathways (i.e., myogenic as well as adipogenic) and possible cross-talk between pathways in AMPD.

Nagarajan, Radhakrishnan; Datta, Sujay; Scutari, Marco; Beggs, Marjorie L.; Nolen, Greg T.; Peterson, Charlotte A.

2010-01-01

439

Functional relationships between genes associated with differentiation potential of aged myogenic progenitors.  

PubMed

Aging is accompanied by considerable heterogeneity with possible co-expression of differentiation pathways. The present study investigates the interplay between crucial myogenic, adipogenic, and Wnt-related genes orchestrating aged myogenic progenitor differentiation (AMPD) using clonal gene expression profiling in conjunction with Bayesian structure learning (BSL) techniques. The expression of three myogenic regulatory factor genes (Myogenin, Myf-5, MyoD1), four genes involved in regulating adipogenic potential (C/EBP?, DDIT3, FoxC2, PPAR?), and two genes in the Wnt signaling pathway (Lrp5, Wnt5a) known to influence both differentiation programs were determined across 34 clones by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Three control genes were used for normalization of the clonal expression data (18S, GAPDH, and B2M). Constraint-based BSL techniques, namely (a) PC Algorithm, (b) Grow-shrink (GS) algorithm, and (c) Incremental Association Markov Blanket (IAMB) were used to model the functional relationships (FRs) in the form of acyclic networks from the clonal expression profiles. A novel resampling approach that obviates the need for a user-defined confidence threshold is proposed to identify statistically significant FRs at small sample sizes. Interestingly, the resulting acyclic network consisted of FRs corresponding to myogenic, adipogenic, Wnt-related genes and their interaction. A significant number of these FRs were robust to normalization across the three house-keeping genes and the choice of the BSL technique. The results presented elucidate the delicate balance between differentiation pathways (i.e., myogenic as well as adipogenic) and possible cross-talk between pathways in AMPD. PMID:21423363

Nagarajan, Radhakrishnan; Datta, Sujay; Scutari, Marco; Beggs, Marjorie L; Nolen, Greg T; Peterson, Charlotte A

2010-09-09

440

Identification of New Differentially Methylated Genes That Have Potential Functional Consequences in Prostate Cancer  

PubMed Central

Many differentially methylated genes have been identified in prostate cancer (PCa), primarily using candidate gene-based assays. Recently, several global DNA methylation profiles have been reported in PCa, however, each of these has weaknesses in terms of ability to observe global DNA methylation alterations in PCa. We hypothesize that there remains unidentified aberrant DNA methylation in PCa, which may be identified using higher resolution assay methods. We used the newly developed Illumina HumanMethylation450 BeadChip in PCa (n?=?19) and adjacent normal tissues (n?=?4) and combined these with gene expression data for identifying new DNA methylation that may have functional consequences in PCa development and progression. We also confirmed our methylation results in an independent data set. Two aberrant DNA methylation genes were validated among an additional 56 PCa samples and 55 adjacent normal tissues. A total 28,735 CpG sites showed significant differences in DNA methylation (FDR adjusted P<0.05), defined as a mean methylation difference of at least 20% between PCa and normal samples. Furthermore, a total of 122 genes had more than one differentially methylated CpG site in their promoter region and a gene expression pattern that was inverse to the direction of change in DNA methylation (e.g. decreased expression with increased methylation, and vice-versa). Aberrant DNA methylation of two genes, AOX1 and SPON2, were confirmed via bisulfate sequencing, with most of the respective CpG sites showing significant differences between tumor samples and normal tissues. The AOX1 promoter region showed hypermethylation in 92.6% of 54 tested PCa samples in contrast to only three out of 53 tested normal tissues. This study used a new BeadChip combined with gene expression data in PCa to identify novel differentially methylated CpG sites located within genes. The newly identified differentially methylated genes may be used as biomarkers for PCa diagnosis.

Kim, Jin W.; Kim, Seong-Tae; Turner, Aubrey R.; Young, Tracey; Smith, Shelly; Liu, Wennuan; Lindberg, Johan; Egevad, Lars; Gronberg, Henrik; Isaacs, William B.; Xu, Jianfeng

2012-01-01

441

Next steps in using accessory minerals to date the evolution of silicic magmas  

NASA Astrophysics Data System (ADS)

Over the past decade, 238U-230Th-206Pb isotopic dating of accessory minerals using the high spatial resolution and sensitivity of ion microprobe analysis has provided new insights into the longevity and thermochemical evolution of silicic magmas, but has also created new questions about the generation, differentiation, and construction of silicic magma chambers. An important conclusion from in situ dating is that accessory minerals such as zircon and allanite in silicic magmas may be 10's to 100's of thousands of years older than their age of eruption. Whether these relatively "old" crystals are derived from long-lived crystal-rich magma reservoirs or inherited due to remelting of frozen intrusions remains a difficult question to answer because long-lived centers of magmatism are characteristically dynamic and are open systems. Nevertheless, not all rhyolites from loci of repeated silicic magmatism carry a dominant "cargo" of antecrystic zircon (or other accessory minerals). Crystal-poor high-silica rhyolites from Coso volcanic field, eastern California, contain a bimodal population of young zircon that yield 238U-230Th ages concordant with their respective late Pleistocene 40Ar/39Ar eruption ages, and a population of Mesozoic zircon that are obvious xenocrysts derived from wallrocks. Rhyolites erupted from La Primavera caldera, Mexico, contain zircon and chevkinite that yield 238U-230Th ages that are within 10's of k.y. of their corresponding eruption ages between ca. 125-85 ka. Antecrysts from intrusions related to older episodes of rhyolitic magmatism appear absent or exceedingly rare. The relatively short timescales between crystallization and eruption suggest that these rhyolites, unlike otherwise similar rhyolites from other systems, were tapped shortly after highly effective differentiation and/or reheating. It is apparent that zircon ages alone are insufficient for resolving the thermochemical and differentiation histories of silicic magmas, and need to be keyed to crystal-scale variations in trace element and isotopic composition, and geothermometry, as well as the compositions and ages of associated major and other accessory phases. Combination of accessory mineral dating and geospeedomety may yield unique information because these methods resolve different aspects of magma evolution over long and short timescales. Zircon crystals from a ca. 260 ka post-collapse rhyolite at Yellowstone caldera yield U-Pb ages that are 10's to 100's of k.y. older than their eruption age, whereas diffusion profiles derived from relatively high temperature rims on sanidine and pyroxenes indicate 10's of k.y. residence since heating and rim growth. These contrasting timescales reflect different aspects of magma evolution. The range of zircon ages is likely to reflect a mixture of recycled crystal residue and renewed crystallization, which is supported by petrographic evidence for inherited plutonic cores in pyroxenes. This combined dating may provide a way to test whether any "old" crystals reflect freeze-thaw thermal cycles in the subvolcanic environment or protracted storage of magma in mushy or melt rich reservoirs.

Vazquez, J. A.

2011-12-01

442

Accessory child safety harnesses: do the risks outweigh the benefits?  

PubMed

Accessory child safety harnesses are available in some countries as alternative restraints for young children or as an accessory restraint used with booster seats. Their use, in Australia at least, is becoming more common. There have been concerns that the risk of misuse of these restraints outweighs any potential benefit this system might have over a retractable lap-shoulder belt system used with a booster seat. However to date there is no evidence to confirm or deny this. This study used laboratory simulated frontal crash tests to examine the performance of accessory child safety harness systems compared to the lap-shoulder belt when used alone and when used with two common designs of Australian booster seat. The performance of the child safety harness system when misused was also investigated. The results demonstrate that the correctly used child safety harness system performed no better than the lap-shoulder system, and in fact allows for a greater risk of submarining. Furthermore, one common form of child safety harness misuse, where the harness is over-tightened causing the lap belt to be positioned high over the abdomen, allowed extremely undesirable dummy motion. This involved gross submarining and direct contact between the harness system and the dummy's neck. These findings suggest that the risks associated with accessory child safety harness systems most likely outweigh any potential benefits, in frontal impacts at least. PMID:19887151

Brown, Julie; Wainohu, Derek; Aquilina, Peter; Suratno, Basuki; Kelly, Paul; Bilston, Lynne E

2009-08-03

443

21 CFR 876.5820 - Hemodialysis system and accessories.  

Code of Federal Regulations, 2010 CFR

A hemodialysis system and accessories is a device that is used as an artificial kidney system for the treatment of patients with renal failure or toxemic conditions and that consists of an extracorporeal blood system, a conventional dialyzer, a dialysate delivery system, and...

2009-04-01

444

21 CFR 876.5820 - Hemodialysis system and accessories.  

Code of Federal Regulations, 2010 CFR

A hemodialysis system and accessories is a device that is used as an artificial kidney system for the treatment of patients with renal failure or toxemic conditions and that consists of an extracorporeal blood system, a conventional dialyzer, a dialysate delivery system, and...

2010-04-01

445

Clothing/Apparel and Accessories Merchandising. A Suggested Interdisciplinary Guide.  

ERIC Educational Resources Information Center

|This curriculum guide contains three sections: introduction, curriculum material, and an annotated bibliography. Introductory information provides an overview of the clothing/apparel and accessories merchandising area, aptitudes needed, and career opportunities; discusses potential career ladders, which are divided into entry level, middle…

Wray, Ralph D.; Hayden, Margaret B.

446

Evolutionary dynamics of the accessory genome of Listeria monocytogenes.  

PubMed

Listeria monocytogenes, a foodborne bacterial pathogen, is comprised of four phylogenetic lineages that vary with regard to their serotypes and distribution among sources. In order to characterize lineage-specific genomic diversity within L. monocytogenes, we sequenced the genomes of eight strains from several lineages and serotypes, and characterized the accessory genome, which was hypothesized to contribute to phenotypic differences across lineages. The eight L. monocytogenes genomes sequenced range in size from 2.85-3.14 Mb, encode 2,822-3,187 genes, and include the first publicly available sequenced representatives of serotypes 1/2c, 3a and 4c. Mapping of the distribution of accessory genes revealed two distinct regions of the L. monocytogenes chromosome: an accessory-rich region in the first 65° adjacent to the origin of replication and a more stable region in the remaining 295°. This pattern of genome organization is distinct from that of related bacteria Staphylococcus aureus and Bacillus cereus. The accessory genome of all lineages is enriched for cell surface-related genes and phosphotransferase systems, and transcriptional regulators, highlighting the selective pressures faced by contemporary strains from their hosts, other microbes, and their environment. Phylogenetic analysis of O-antigen genes and gene clusters predicts that serotype 4 was ancestral in L. monocytogenes and serotype 1/2 associated gene clusters were putatively introduced through horizontal gene transfer in the ancestral population of L. monocytogenes lineage I and II. PMID:23825666

den Bakker, Henk C; Desjardins, Christopher A; Griggs, Allison D; Peters, Joseph E; Zeng, Qiandong; Young, Sarah K; Kodira, Chinnappa D; Yandava, Chandri; Hepburn, Theresa A; Haas, Brian J; Birren, Bruce W; Wiedmann, Martin

2013-06-25

447

21 CFR 884.1600 - Transabdominal amnioscope (fetoscope) and accessories.  

Code of Federal Regulations, 2013 CFR

...Date premarket approval application (PMA) or notice of completion of a product development protocol (PDP) is required. A PMA or a notice of completion of a PDP...and accessories shall have an approved PMA or a declared completed PDP in effect...

2013-04-01

448

Advancement of Small Gas Turbine Engine Accessory Technology.  

National Technical Information Service (NTIS)

The basic requirements for controls and accessories for gas generators in the 2-to-5 pound per second airflow range are established. These requirements are then investigated in terms of current and projected state-of-the-art relative to the various contro...

H. L. Richardson R. M. Tommasini

1967-01-01

449

Basketry accessories: footwear, bags and fans in ancient Egypt  

Microsoft Academic Search

Ancient Egyptians had —by the New Kingdom— developed many basket making and matting techniques. These techniques were not only used for making all types and sizes of baskets and mats, but were also adopted for making other accessories such as bags, fans and different types of footwear, that seem to have been heavily used. Materials and techniques of nine objects

N. M. N. El Hadidi; R. Hamdy

2011-01-01

450

Schwannoma of the Spinal Accessory Nerve: A Case Report  

PubMed Central

We are reporting a rare case of a schwannoma which originated from the cervical portion of the spinal accessory nerve, which was located in the left posterior triangle of the neck and did not have any neurological deficit, which was diagnosed by the Magnetic Resonance Imaging (MRI) scan and confirmed histopathologically after surgery.

Kohli, Ritesh; Singh, Surinder; Gupta, Sahwani K.; Matreja, Prithpal S.

2013-01-01

451

49 CFR 192.147 - Flanges and flange accessories.  

Code of Federal Regulations, 2011 CFR

...flange or flange accessory (other than cast iron) must meet the minimum requirements...Each flange on a flanged joint in cast iron pipe must conform in dimensions...design to ASME/ANSI B16.1 and be cast integrally with the pipe,...

2011-10-01

452

Patent Accessory Canals: Incidence in Molar Furcation Region.  

National Technical Information Service (NTIS)

A total of 46 extracted maxillary and mandibular molars were examined to determine the incidence of accessory canals in the coronal and middle third of the root surface. A radiopaque dye was drawn through the root canal system under a vacuum of 5 p.s.i., ...

J. V. Lowman R. S. Burke G. B. Pelleu

1974-01-01

453

Mrap2: an accessory protein linked to obesity.  

PubMed

Melanocortin receptors are critical modulators of energy balance and glucose homeostasis. Companion studies published in Science (Asai et al., 2013; Sebag et al., 2013) establish a role for melanocortin receptor accessory protein 2 (Mrap2) in regulating melanocortin receptor activity and in the development of obesity in zebrafish, rodents, and humans. PMID:24011068

Liu, Tiemin; Elmquist, Joel K; Williams, Kevin W

2013-09-01

454

HIV-1 Nef Sequence and Functional Compartmentalization in the Gut Is Not Due to Differential Cytotoxic T Lymphocyte Selective Pressure  

PubMed Central

The gut is the largest lymphoid organ in the body and a site of active HIV-1 replication and immune surveillance. The gut is a reservoir of persistent infection in some individuals with fully suppressed plasma viremia on combination antiretroviral therapy (cART) although the cause of this persistence is unknown. The HIV-1 accessory protein Nef contributes to persistence through multiple functions including immune evasion and increasing infectivity. Previous studies showed that Nef’s function is shaped by cytotoxic T lymphocyte (CTL) responses and that there are distinct populations of Nef within tissue compartments. We asked whether Nef’s sequence and/or function are compartmentalized in the gut and how compartmentalization relates to local CTL immune responses. Primary nef quasispecies from paired plasma and sigmoid colon biopsies from chronically infected subjects not on therapy were sequenced and cloned into Env? Vpu? pseudotyped reporter viruses. CTL responses were mapped by IFN-? ELISpot using expanded CD8+ cells from blood and gut with pools of overlapping peptides covering the entire HIV proteome. CD4 and MHC Class I Nef-mediated downregulation was measured by flow cytometry. Multiple tests indicated compartmentalization of nef sequences in 5 of 8 subjects. There was also compartmentalization of function with MHC Class I downregulation relatively well preserved, but significant loss of CD4 downregulation specifically by gut quasispecies in 5 of 7 subjects. There was no compartmentalization of CTL responses in 6 of 8 subjects, and the selective pressure on quasispecies correlated with the magnitude CTL response regardless of location. These results demonstrate that Nef adapts via diverse pathways to local selective pressures within gut mucosa, which may be predominated by factors other than CTL responses such as target cell availability. The finding of a functionally distinct population within gut mucosa offers some insight into how HIV-1 may persist in the gut despite fully suppressed plasma viremia on cART.

Lewis, Martha J.; Frohnen, Patricia; Ibarrondo, F. Javier; Reed, Diane; Iyer, Varun; Ng, Hwee L.; Elliott, Julie; Yang, Otto O.; Anton, Peter

2013-01-01

455

HIV-1 Nef Sequence and Functional Compartmentalization in the Gut Is Not Due to Differential Cytotoxic T Lymphocyte Selective Pressure.  

PubMed

The gut is the largest lymphoid organ in the body and a site of active HIV-1 replication and immune surveillance. The gut is a reservoir of persistent infection in some individuals with fully suppressed plasma viremia on combination antiretroviral therapy (cART) although the cause of this persistence is unknown. The HIV-1 accessory protein Nef contributes to persistence through multiple functions including immune evasion and increasing infectivity. Previous studies showed that Nef's function is shaped by cytotoxic T lymphocyte (CTL) responses and that there are distinct populations of Nef within tissue compartments. We asked whether Nef's sequence and/or function are compartmentalized in the gut and how compartmentalization relates to local CTL immune responses. Primary nef quasispecies from paired plasma and sigmoid colon biopsies from chronically infected subjects not on therapy were sequenced and cloned into Env(-) Vpu(-) pseudotyped reporter viruses. CTL responses were mapped by IFN-? ELISpot using expanded CD8+ cells from blood and gut with pools of overlapping peptides covering the entire HIV proteome. CD4 and MHC Class I Nef-mediated downregulation was measured by flow cytometry. Multiple tests indicated compartmentalization of nef sequences in 5 of 8 subjects. There was also compartmentalization of function with MHC Class I downregulation relatively well preserved, but significant loss of CD4 downregulation specifically by gut quasispecies in 5 of 7 subjects. There was no compartmentalization of CTL responses in 6 of 8 subjects, and the selective pressure on quasispecies correlated with the magnitude CTL response regardless of location. These results demonstrate that Nef adapts via diverse pathways to local selective pressures within gut mucosa, which may be predominated by factors other than CTL responses such as target cell availability. The finding of a functionally distinct population within gut mucosa offers some insight into how HIV-1 may persist in the gut despite fully suppressed plasma viremia on cART. PMID:24058696

Lewis, Martha J; Frohnen, Patricia; Ibarrondo, F Javier; Reed, Diane; Iyer, Varun; Ng, Hwee L; Elliott, Julie; Yang, Otto O; Anton, Peter

2013-09-13

456

Differential effect of calsequestrin ablation on structure and function of fast and slow skeletal muscle fibers.  

PubMed

We compared structure and function of EDL and Soleus muscles in adult (4-6?m) mice lacking both Calsequestrin (CASQ) isoforms, the main SR Ca²?-binding proteins. Lack of CASQ induced ultrastructural alterations in ~30% of Soleus fibers, but not in EDL. Twitch time parameters were prolonged in both muscles, although tension was not reduced. However, when stimulated for 2?sec at 100?hz, Soleus was able to sustain contraction, while in EDL active tension declined by 70-80%. The results presented in this paper unmask a differential effect of CASQ1&2 ablation in fast versus slow fibers. CASQ is essential in EDL to provide large amount of Ca²? released from the SR during tetanic stimulation. In contrast, Soleus deals much better with lack of CASQ because slow fibers require lower Ca²? amounts and slower cycling to function properly. Nevertheless, Soleus suffers more severe structural damage, possibly because SR Ca²? leak is more pronounced. PMID:21941434

Paolini, Cecilia; Quarta, Marco; D'Onofrio, Laura; Reggiani, Carlo; Protasi, Feliciano

2011-09-14

457

Differential Effect of Calsequestrin Ablation on Structure and Function of Fast and Slow Skeletal Muscle Fibers  

PubMed Central

We compared structure and function of EDL and Soleus muscles in adult (4–6?m) mice lacking both Calsequestrin (CASQ) isoforms, the main SR Ca2+-binding proteins. Lack of CASQ induced ultrastructural alterations in ~30% of Soleus fibers, but not in EDL. Twitch time parameters were prolonged in both muscles, although tension was not reduced. However, when stimulated for 2?sec at 100?hz, Soleus was able to sustain contraction, while in EDL active tension declined by 70–80%. The results presented in this paper unmask a differential effect of CASQ1&2 ablation in fast versus slow fibers. CASQ is essential in EDL to provide large amount of Ca2+ released from the SR during tetanic stimulation. In contrast, Soleus deals much better with lack of CASQ because slow fibers require lower Ca2+ amounts and slower cycling to function properly. Nevertheless, Soleus suffers more severe structural damage, possibly because SR Ca2+ leak is more pronounced.

Paolini, Cecilia; Quarta, Marco; D'Onofrio, Laura; Reggiani, Carlo; Protasi, Feliciano

2011-01-01

458

Accessory flexor digitorum longus presenting as tarsal tunnel syndrome: a case report.  

PubMed

The flexor digitorum accessory longus (FDAL) muscle is one of the most commonly encountered anomalous muscles in the foot and ankle. Literature has documented the prevalence of the FDAL anywhere from 4% to 12%, based on cadaveric limb dissection. The variability of the origin, insertion, size, and location of the FDAL muscle can cause a wide array of foot and ankle pathologies, most notably, tarsal tunnel syndrome and flexor hallucis longus syndrome. Accessory musculature should be included in the list of differential diagnoses for foot and ankle pain until proven otherwise. This report presents a patient who exhibited pain localized to the medial malleolar region and was initially diagnosed with likely tarsal tunnel syndrome. On magnetic resonance imaging, a FDAL muscle was identified and shown to be impinging on the posterior medial anatomic structures. The patient underwent excision of the FDAL and is symptom free to date. The discussion of this case report can prompt foot and ankle surgeons to be more aware of this infrequent finding as well as treatment options. Level of Evidence: Therapeutic, Level IV. PMID:21926358

Saar, William E; Bell, Jennifer

2011-09-16

459

Growth-differentiation factor-15 and functional outcome after acute ischemic stroke.  

PubMed

Blood biomarkers may improve the performance in predicting early stroke outcome beyond well-established clinical factors. We investigated the value of growth-differentiation factor-15 (GDF-15) to predict functional outcome after 90 days in a prospectively collected patient cohort with symptoms of acute ischemic stroke. Two hundred eighty-one patients with symptoms of acute ischemic stroke were prospectively investigated. Serial blood samples for GDF-15 analysis were obtained after the admission of the patient, after 6 and 24 h. Primary outcome was the dichotomized modified ranking scale (MRS) 90 days after the initial clinical event. Within the final study population (264 patients, mean age 70.3 ± 12.7 years, 55.3% male), National Institutes of Health Stroke Scale (NIH-SS) [odds ratio (OR) 1.269, 95% confidence interval (CI) 1.141-1.412, p < 0.001] and initial GDF-15 levels (OR 1.029, 95% CI 1.007-1.053, p = 0.011) were independently associated with a MRS ? 2 after day 90 after multiple regression analysis. Growth-differentiation factor-15 levels increase with higher NIH-SS-tertiles (p = 0.005). Receiver-operator characteristic curves demonstrated a discriminatory accuracy to predict unfavourable stroke outcome of 0.629 (95% CI 0.558-0.699), 0.753 (95% CI 0.693-812) and 0.774 (95% CI 0.717-0.832) for GDF-15, NIH-SS and the combination of these variables. The additional use of GDF-15 to NIH-SS ameliorates the model with a net reclassification index of 0.044 (p = 0.541) and integrated discrimination improvement of 0.034 (p = 0.443). Growth-differentiation factor-15 as an acute stroke biomarker independently predicts unfavourable functional 90 day stroke outcome. Discriminatory value in addition to NIH-SS is only modestly distinct. PMID:22231869

Gröschel, Klaus; Schnaudigel, Sonja; Edelmann, Frank; Niehaus, Cord-Friedrich; Weber-Krüger, Mark; Haase, Beatrice; Lahno, Rosine; Seegers, Joachim; Wasser, Katrin; Wohlfahrt, Janin; Vollmann, Dirk; Stahrenberg, Raoul; Wachter, Rolf

2012-01-10

460

Thymosin-?1 modulates dendritic cell differentiation and functional maturation from human peripheral blood CD14+ monocytes  

PubMed Central

Summary Although thymosins have been demonstrated to have immunomodulatory effects, it is still not clear whether they could affect dendritic cells (DCs), the most professional antigen-presenting cells. The objective of this study was to determine the effect and potential mechanisms of thymosin-?1 (T?1) on DC differentiation and functional maturation. Human peripheral blood CD14+ monocytes were purified by using a magnetic separation column and cultured with GM-CSF and IL-4 to differentiate into immature DCs (iDCs). In the presence of T?1, iDC surface markers CD40, CD80, MHC class I and class II molecules were significantly upregulated as measured by flow cytemotry analysis. However, T?4 or T?10 did not show these effects on iDCs. There was approximately a 30% reduction in antigen (FITC-conjugated dextran)-uptake by T?1-treated iDCs as compared with non-T?1-treated iDCs. In addition, T?1-treated matured DCs (mDCs) showed an increased stimulation of allogeneic CD3+ T-cell proliferation as measured by a mixed-lymphocyte reaction assay. T?1-treated mDCs also increased the production of several Th1- and Th2-type cytokines as measured by a Bio-Plex cytokine assay. Furthermore, rapid activation of p38 MAPK and NF?B was seen in T?1-treated iDCs as measured by a Bio-Plex phosphoprotein assay. T?1 significantly enhances on DC differentiation, activation and functions from human peripheral blood CD14+ monocytes possiblly through a mechanism of the activation of p38 MAPK and NF?B pathways. This study provides a basis to further evaluate T?1 as a possible adjuvant for a DC-directed vaccine or therapy.

Yao, Qizhi; Doan, Linh X.; Zhang, Rongxin; Bharadwaj, Uddalak; Li, Min; Chen, Changyi

2007-01-01

461

Holistic systems biology approaches to molecular mechanisms of human helper T cell differentiation to functionally distinct subsets.  

PubMed

Current knowledge of helper T cell differentiation largely relies on data generated from mouse studies. To develop therapeutical strategies combating human diseases, understanding the molecular mechanisms how human naïve T cells differentiate to functionally distinct T helper (Th) subsets as well as studies on human differentiated Th cell subsets is particularly valuable. Systems biology approaches provide a holistic view of the processes of T helper differentiation, enable discovery of new factors and pathways involved and generation of new hypotheses to be tested to improve our understanding of human Th cell differentiation and immune-mediated diseases. Here, we summarize studies where high-throughput systems biology approaches have been exploited to human primary T cells. These studies reveal new factors and signalling pathways influencing T cell differentiation towards distinct subsets, important for immune regulation. Such information provides new insights into T cell biology and into targeting immune system for therapeutic interventions. PMID:23679154

Chen, Z; Lönnberg, T; Lahesmaa, R

2013-08-01

462

A Cross-Cultural Analysis of Consumers’ Conspicuous Consumption of Branded Fashion Accessories  

Microsoft Academic Search

The study attempts to (1) demonstrate whether the purchase of branded fashion accessories is motivated by consumers’ desire to reflect their social status, convey their self-image, and boost their self-esteem; (2) find whether the purchase of luxury fashion accessories may fall under the umbrella of conspicuous consumption; and (3) examine whether conspicuous consumption of branded fashion accessories varies across cultures.

Nizar Souiden; Bouthaina M’Saad; Frank Pons

2011-01-01

463

Tyrosine Kinase Signaling Regulates Wiskott-Aldrich Syndrome Protein Function, Which Is Essential for Megakaryocyte Differentiation  

Microsoft Academic Search

Platelets are produced from megakaryocytes differentiated from megakaryoblasts, but the differentiation mechanism still remains unknown. Here, we demonstrate that a tyrosine kinase signaling regulates Wiskott-Aldnch syndrome protein (WASP), which is essential for megakaryocyte differentiation.

Hiroaki Miki; Shigeaki Nonoyama; Qili Zhu; Alejandro Aruffo; Hans D. Ochs; Tadaomi Takenawa

464

Structural and Mutational Analysis of Functional Differentiation between Synaptotagmins-1 and -7  

SciTech Connect

Synaptotagmins are known to mediate diverse forms of Ca{sup 2+}-triggered exocytosis through their C{sub 2} domains, but the principles underlying functional differentiation among them are unclear. Synaptotagmin-1 functions as a Ca{sup 2+} sensor in neurotransmitter release at central nervous system synapses, but synaptotagmin-7 does not, and yet both isoforms act as Ca{sup 2+} sensors in chromaffin cells. To shed light into this apparent paradox, we have performed rescue experiments in neurons from synaptotagmin-1 knockout mice using a chimera that contains the synaptotagmin-1 sequence with its C{sub 2}B domain replaced by the synaptotagmin-7 C{sub 2}B domain (Syt1/7). Rescue was not achieved either with the WT Syt1/7 chimera or with nine mutants where residues that are distinct in synaptotagmin-7 were restored to those present in synaptotagmin-1. To investigate whether these results arise because of unique conformational features of the synaptotagmin-7 C{sub 2}B domain, we determined its crystal structure at 1.44 {angstrom} resolution. The synaptotagmin-7 C{sub 2}B domain structure is very similar to that of the synaptotagmin-1 C{sub 2}B domain and contains three Ca{sup 2+}-binding sites. Two of the Ca{sup 2+}-binding sites of the synaptotagmin-7 C{sub 2}B domain are also present in the synaptotagmin-1 C{sub 2}B domain and have analogous ligands to those determined for the latter by NMR spectroscopy, suggesting that a discrepancy observed in a crystal structure of the synaptotagmin-1 C{sub 2}B domain arose from crystal contacts. Overall, our results suggest that functional differentiation in synaptotagmins arises in part from subtle sequence changes that yield dramatic functional differences.

Xue, Mingshan; Craig, Timothy K.; Shin, Ok-Ho; Li, Liyi; Brautigam, Chad A.; Tomchick, Diana R.; Südhof, Thomas C.; Rosenmund, Christian; Rizo, Josep (Baylor); (UTSMC); (Texas)

2012-01-20

465

Osteopontin Splice Variants Differentially Exert Clinicopathological Features and Biological Functions in Gastric Cancer  

PubMed Central

Purpose: Gastric cancer (GC) remains a leading cause of death worldwide, and an elevated expression of osteopontin (OPN) may correlate with its poor survival. Alternative splicing of OPN can result in three isoforms, OPN-a, OPN-b and OPN-c. The aim of our current study is to examine the expression pattern and biological functions of OPN splice variants in GC. Methods: Firstly, we evaluated the expression of OPN splice variants in 7 gastric cell lines, 101 pairs of GC tissues and their adjacent non-tumor tissues by Quantative real-time PCR (QT-PCR). Gain-of-function experiments were subsequently performed to determine their diverse roles in malignant behaviors of GC. Besides, their differential e