bluuebunny/crossref_metadata_2025 huggingface dataset:
Production and processing of POMC peptides by dermal microvascular endothelial cells (EC): modulation of EC biologic functions and implication for skin inflammation.
Authors: Scholzen T.E. , Koenig S. , Fastrich M. , Böhm M. , Luger T.A.
Published: January 2005

The availability of neuropeptides or neuroendocrine hormones as important modulators of innate and adaptive immune responses is effectively controlled by neuropeptide‐specific peptidases. In previous studies, drug inhibition or genomic deletion of neutral endopeptidase (NEP, CD10) or of angiotensin‐converting enzyme (ACE, CD143) resulted in a profound augmentation of murine allergic contact dermatitis responses. Likewise, we have identified dermal microvascular endothelial cells (EC) as both source and target of the proopiomelanocortin (POMC) peptides ACTH and α‐melanocyte‐stimulating hormone (α‐MSH), in particular. EC express melanocortin receptor (MC‐) 1 and α‐MSH is capable of profoundly downregulating LPS‐ or cytokine‐induced expression of adhesion molecules in vitro and of endotoxin‐induced cutaneous vasculitis in vivo. In this study, we have tested the hypothesis that NEP or ACE expressed by EC may influence the local bioavailability of POMC peptides. Cell membranes prepared from the high NEP/low ACE expressing human microvascular endothelial cell line 1 (HMEC‐1) or from low NEP/high ACE expressing primary human dermal EC (HDMEC) were incubated for 30–480 min with ACTH1–39 in the presence or absence of NEP or ACE inhibitors, respectively. Analysis of membrane supernatants for ACTH and α‐MSH by radioimmunoassay revealed a decrease in ACTH immunoreactivity (IR) over time that could be partially blocked with NEP inhibitors. In parallel, α‐MSH IR increased peaking after 60 min. Fragments generated by incubation of HMEC‐1 or HDMEC membranes with ACTH1–39, ACHT1–24 or α‐MSH for 1–120 min were further analyzed by Matrix‐assisted‐LASER desorption time‐of‐flight (MALDI‐TOF) spectroscopy. HMEC‐1 membranes generated main peptide products with molecular masses of 2007, 1057 and 945, respectively, from ACTH1–39, and 1057 from ACTH1–24. Inhibition with NEP, but not ACE inhibitors altered the fragmentation profile indicating that NEP is involved in degradation of both ACTH1–39 and ACTH1–24. Likewise, HDMEC membranes fragmented ACTH similar to HMEC‐1 membranes in the presence of NEP inhibitors. Both HMEC‐1 and HDMEC membranes were also capable of slowly degrading α‐MSH suggesting that EC proteolytic peptidases are important for the local control of ACTH/α‐MSH bioavailability, which may play a significant role in controlling local cutaneous inflammatory responses.
cAMP levels inhibit TGF‐β‐induced expression of extracellular matrix (ECM) components by interfering with the SMAD pathway. A potential effector mechanism of hormones signaling via cAMP?
Authors: Schiller M. , Böhm M. , Luger TA , Mauviel A.
Published: January 2005

Through their ability to modulate the expression of extracellular matrix (ECM) components and ECM‐degrading enzymes, cytokines and growth factors orchestrate the balance between ECM destruction and neosynthesis and therefore play an important role in the control of tissue homeostasis and repair. Disruption of the fragile equilibrium between anabolic and catabolic cytokines in favor of TGF‐β may lead to excessive collagen deposition, the hallmark of fibrotic conditions. TGF‐β elicits its effects on target genes through Smad proteins, which transduce signals from TGF‐β receptors into the nucleus where they bind directly to specific promoter sequences. Using an artificial Smad3/4 dependent reporter construct, we show that synthetic cAMP, prevents TGF‐β‐induced Smad‐specific gene transactivation in human dermal fibroblasts. Activation of adenylate cyclase by forskolin mimics the shown Smad opposing effect. Northern blot studies reveal that cAMP inhibits TGF‐β/SMAD‐dependent α(2) type I collagen and type 1 plasminogen activator inhibitor gene expression. In addition, TGF‐β‐induced C‐terminal propeptide of type I procollagen secretion into cell supernatants is significantly inhibited by cAMP. Together these results demonstrate the suppression of TGF‐β‐induced expression of ECM components by increased intracellular cAMP levels. Our data support the notion that various hormones and neuropeptides, which signal via the cAMP pathway, may function as antagonists of fibrosis.
What is the pathogenesis of acne?
Authors: Zouboulis C. C. , Eady A. , Philpott M. , Goldsmith L. A. , Orfanos C. , Cunliffe W. C. , Rosenfield R.
Published: January 2005

Abstract:  For a long time, the mantra of acne pathogenesis debates has been that acne vulgaris lesions develop when (supposedly largely androgen‐mediated) increased sebum production, ductal hypercornification, and propionibacteria come together with local inflammatory process in the unlucky affected individual. And yet, the exact sequence, precise interdependence, and choreography of pathogenic events in acne, especially the ‘match that lights the fire’ have remained surprisingly unclear, despite the venerable tradition of acne research over the past century.

However, exciting recent progress in this – conceptually long somewhat stagnant, yet clinically, psychologically, and socioeconomically highly relevant – everyday battlefield of skin pathology encourages one to critically revisit conventional concepts of acne pathogenesis. Also, this provides a good opportunity for defining more sharply key open questions and intriguing acne characteritics whose underlying biological basis has far too long remained uninvestigated, and to emphasize promising new acne research avenues off‐the‐beaten‐track – in the hope of promoting the corresponding development of innovative strategies for acne management.
Involvement of the EN‐2 gene in normal and abnormal development of the human arcuate nucleus
Authors: Lavezzi Anna Maria , Ottaviani Giulia , Mauri Maria , Terni Lorella , Matturri Luigi
Published: January 2005

In this study, we wanted to evaluate whether the engrailed EN‐2 gene, a homeobox gene with an essential role in the development of the rhombic lip derivatives in different species, is (1) expressed also in man in the differentiation process of the medullary arcuate nucleus (ArcN) and (2) involved in sudden unexplained perinatal and infant death, frequently related to developmental defects of the ArcN. We evaluated by means of the monoclonal antibody 4D9, exclusively recognizing engrailed‐2 protein, the expression of the EN‐2 gene in the ArcN on histological sections of the brainstems of 30 subjects aged from 17 gestational weeks to 10 postnatal months, who had died of known (17 cases) and unknown causes (13 cases). We observed in the greater number of the cases that the expression of the EN‐2 gene is very high in the ArcN neurons from the 17th to the 22nd gestational week, then decreases up to the first days after birth and later disappears. Moreover, in eight of the 13 sudden deaths (61%), a hypoplasia of the ArcN was present. In almost all of these cases, EN‐2 expression was negative. In conclusion, we support the role of the EN‐2 gene in the normal neuronal development and in the anatomic organization of the human ArcN as well as the possible existence of EN‐2 mutations related to hypoplasia of this nucleus.
Hepatocyte progenitors in man and in rodents – multiple pathways, multiple candidates
Authors: Laurson Joanna , Selden Clare , Hodgson Humphrey J. F.
Published: January 2005

In severe injury, liver‐cell progenitors may play a role in recovery, proliferating, and subsequently differentiating into mature liver cells. Identifying these progenitors has major therapeutic potential for ex vivo pharmaceutical testing, bioartificial liver support, tissue engineering and gene therapy protocols. Potential liver‐cell progenitors have been identified from bone marrow, peripheral blood, cord blood, foetal liver, adult liver and embryonic stem cells. Differences and similarities are found among cells isolated from rodents and humans. This review will discuss identifying markers and differentiation potential in in vitro and in vivo models of these putative progenitors in both humans and rodents.
Apoptosis in chronic viral hepatitis parallels histological activity: An immunohistochemical investigation using anti‐activated caspase‐3 and M30 Cytodeath antibody
Authors: McPartland Jo L. , Guzail Muna Ali , Kendall Charles H. , Pringle James Howard
Published: January 2005

Apoptosis is implicated as a major pathogenic mechanism in chronic hepatitis B and C. Previous studies of the relationship between apoptotic rates and histological necroinflammatory activity have produced conflicting results. Hepatocyte apoptosis was assessed in liver tissue from 32 cases of chronic viral hepatitis, seven cases of hepatocellular carcinoma (HCC) and six cases of steatohepatitis as non‐viral disease controls and eight cases of control liver. Apoptotic rates were measured using H&E morphological assessment and immunohistochemical staining with antibodies to activated caspase‐3 and M30. Histological necroinflammatory activity of viral hepatitis cases was scored using the Knodell scoring system, and the cases were divided according to their score into group 1 (mean 2.43 ± 0.48) and group 2 (mean 7.80 ± 0.49). Apoptotic indices were significantly higher in group 2 than group 1 using H&E (11.53 ± 2.70 vs. 0 ± 0, P = 0.015) and activated caspase‐3 (22.01 ± 5.27 vs. 1.79 ± 1.79, P = 0.03) methods but were not significantly higher with M30 (3.80 ± 1.74 vs. 0 ± 0, P = 0.207). Apoptotic scores using an antibody to activated caspase‐3 are significantly higher in cases of chronic viral hepatitis with greater histological necroinflammatory scores, supporting a central role for apoptosis in disease pathogenesis. This method offers an alternative to routine histological assessment for measuring disease activity.
Histopathology of spleen allograft rejection in miniature swine
Authors: Dor Frank J. M. F. , Gollackner Bernd , Kuwaki Kenji , Ko Dicken S. C. , Cooper David K. C. , Houser Stuart L.
Published: January 2005

Spleen transplantation (SpTx) has established donor‐specific tolerance in rodents, but not in large animals or humans. We report the histopathology of rejection in an established model of SpTx in major histocompatibility complex (MHC)‐defined miniature swine. Of the 17 SpTx, rejection was observed in two grafts transplanted into untreated, MHC‐matched, minor antigen‐disparate recipients (group 1, n = 4), but not in the two that received a 12‐day course of cyclosporin A (CyA). Rejection also occurred in five grafts transplanted into fully MHC‐disparate recipients (group 2, n = 12), one of which was untreated and four of which received some form of immunosuppressive therapy. One recipient of an MHC class‐I‐mismatched spleen treated with 12 days of CyA did not show rejection. Following biopsy and/or necropsy, fixed allograft tissue sections were treated with multiple stains, immunohistochemical markers and TUNEL assay. Common features of rejection occurred in grafts from both groups, but with varying time courses. Necrosis developed as early as day 8 in group 2 and day 27 in group 1, ranging from focal fibrinoid necrosis of arteriolar walls and sinusoids to diffuse liquefactive necrosis, usually associated with haemorrhage. Other features of rejection included white pulp expansion by atypical cells and decreased staining of basement membranes and reticular fibres. A doubling of the baseline TUNEL index preceded histologically identifiable rejection. This study establishes histologic guidelines for diagnosing and, perhaps, in future studies, predicting acute rejection of splenic allografts transplanted across known histocompatibility barriers in a large‐animal model.
A dyadic assessment of forgiveness in intimate relationships
Authors: Friesen Myron D. , Fletcher Garth J. O. , Overall Nickola C.
Published: January 2005

This study investigated forgiveness by examining couples’ recollections and perceptions of specific incidents of transgressions in their relationships. The results replicated previous research but also produced some novel findings. Results showed that more positive attributions and relationship quality independently predicted higher internal forgiveness, whereas expressed forgiveness was related only to relationship quality. Overall, the sample was negatively biased in their perceptions of their partner's forgiveness, but those participants who tended toward a positive bias were happier with their relationships as were their partners. Results are discussed in terms of prior research and theories of forgiveness and related social judgments in intimate relationships.
Three measures of closeness in adolescents’ relationships with parents and friends: Variations and developmental significance
Authors: Repinski Daniel J. , Zook Joan M.
Published: January 2005

Two studies examined the nature and developmental significance of closeness in adolescents’ relationships with parents and friends. Three measures of relationship closeness (i.e., interdependence, emotional tone, and subjective opinion) were compared and contrasted. In Study 1, grade and gender differences in closeness in relationships with mothers, fathers, and friends were examined. Participants were 133 adolescents in Grades 7, 9, and 11 and 135 of their parents. Closeness in relationships with mothers, fathers, and friends varied based on closeness measure, grade of adolescent, gender of adolescent, and gender of parent. The results suggest that the interdependence measure offers a perspective on adolescents’ close relationships that differs from that provided by the emotional tone and subjective opinion measures. In Study 2, associations were examined between the three measures of closeness in adolescents’ relationships with mothers, fathers, and friends and adolescents’ problem behavior, substance use, and school performance. Participants included 107 adolescents in Grades 7 and 10. In combination, the measures of closeness in relationships with mothers and with fathers explained significant variability in the criterion variables, and reports of interdependence and emotional tone emerged as unique, significant predictors. The results highlight distinctions among the three conceptualizations that are commonly purported to assess a close relationship and point to the utility and validity of interdependence and emotional tone as measures of closeness in adolescents’ relationships.
Endothelin‐1‐induced proliferation of human endothelial cells depends on activation of K+ channels and Ca2+ influx
Authors: Kuhlmann C. R. W. , Most A. K. , Li F. , Münz B. M. , Schaefer C. A. , Walther S. , Raedle‐Hurst T. , Waldecker B. , Piper H. M. , Tillmanns H. , Wiecha J.
Published: January 2005

Aims:  Endothelin‐1 (ET‐1) promotes endothelial cell growth. Endothelial cell proliferation involves the activation of Ca2+‐activated K+ channels. In this study, we investigated whether Ca2+‐activated K+ channels with big conductance (BKCa) contribute to endothelial cell proliferation induced by ET‐1.

Methods:  The patch‐clamp technique was used to analyse BKCa activity in endothelial cells derived from human umbilical cord veins (HUVEC). Endothelial proliferation was examined using cell counts and measuring [3H]‐thymidine incorporation. Changes of intracellular Ca2+ levels were examined using fura‐2 fluorescence imaging.

Results:  Characteristic BKCa were identified in cultured HUVEC. Continuous perfusion of HUVEC with 10 nmol L−1 ET‐1 caused a significant increase of BKCa open‐state probability (n = 14; P < 0.05; cell‐attached patches). The ETB‐receptor antagonist (BQ‐788, 1 μmol L−1) blocked this effect. Stimulation with Et‐1 (10 nmol L−1) significantly increased cell growth by 69% (n = 12; P < 0.05). In contrast, the combination of ET‐1 (10 nmol L−1) and the highly specific BKCa blocker iberiotoxin (IBX; 100 nmol L−1) did not cause a significant increase in endothelial cell growth. Ca2+ dependency of ET‐1‐induced proliferation was tested using the intracellular Ca2+‐chelator BAPTA (10 μmol L−1). BAPTA abolished ET‐1 induced proliferation (n = 12; P < 0.01). In addition, ET‐1‐induced HUVEC growth was significantly reduced, if cells were kept in a Ca2+‐reduced solution (0.3 mmol L−1), or by the application of 2 aminoethoxdiphenyl borate (100 μmol L−1) which blocks hyperpolarization‐induced Ca2+ entry (n = 12; P < 0.05).

Conclusion:  Activation of BKCa by ET‐1 requires ETB‐receptor activation and induces a capacitative Ca2+ influx which plays an important role in ET‐1‐mediated endothelial cell proliferation.
Polyethylene glycol but not mifepristone prevents intestinal lymphocyte loss following treadmill exercise in mice
Authors: Quadrilatero J. , Guan J. , Boudreau J. , Marra S. , Hoffman‐Goetz L.
Published: January 2005

Circulating lymphocyte numbers decrease following intense physical activity, possibly due to exercise‐induced apoptosis. Increased reactive oxygen species (ROS) and glucocorticoids (GC) following exercise contribute to lymphocyte apoptosis. Intestinal lymphocyte (IL) numbers also decrease following exercise.

Aim:  The purpose of this study was to determine the contribution of GC to exercise‐induced IL loss.

Methods:  Female C57BL/6 mice (n = 178) were randomized to five drug conditions: (1) single injection of the glucocorticoid receptor antagonist mifepristone (MIF) solubilized in polyethylene glycol (PEG); (2) three injections of MIF (repeated MIF) PEG; (3) single injection of PEG (PEG); (4) three injections of PEG (repeated PEG); or (5) repeated injections of saline (SAL). Within each drug group mice were further randomized to exercise conditions: (1) control condition (non‐exercised); (2) treadmill running with sacrifice immediately following the exercise; or (3) treadmill running with sacrifice 24 h after completion of the exercise.

Results:  There was a significant exercise effect, across all T lymphocyte subsets, in SAL (P < 0.01), PEG (P < 0.01) and MIF (P < 0.01) treated mice but not in mice given repeated PEG or repeated MIF exposure. The exercise effect was due to reduced IL numbers 24 h post‐exercise compared with non‐exercised controls.

Conclusion:  These results suggest that GC are not directly responsible for IL cell loss following exercise. Repeated exposure to PEG may confer protection in the gastrointestinal tract from exercise‐induced lymphocyte depletion. Because PEG inhibits ROS generation in experimental cell injury, the mechanisms for IL loss after exercise may involve oxidative stress.
Regional intestinal adaptations in Na+,K+‐ATPase in experimental colitis and the contrasting effects of interferon‐γ
Authors: Magro F. , Fraga S. , Ribeiro T. , Soares‐da‐Silva P.
Published: January 2005

Aims:  This study evaluated Na+,K+‐ATPase activity and the abundance of α1 subunit Na+,K+‐ATPase in experimental colitis and gathered evidence on the effects of interferon‐γ (IFN‐γ) on intestinal Na+,K+‐ATPase.

Methods:  Colitis was induced by the intrarectal administration of 2,4,6‐trinitrobenzene sulphonic acid (TNBS, 30 mg/250 μL). Na+,K+‐ATPase activity was determined as the difference between total and ouabain‐insensitive ATPase. The abundance of Na+,K+‐ATPase was analysed by immunoblotting.

Results:  Na+,K+‐ATPase activity was markedly reduced in the proximal colonic mucosa of TNBS‐treated rats, whereas upstream in the terminal ileal mucosa a marked increase in sodium pump activity was observed. At the jejunal level no significant changes in Na+,K+‐ATPase activity were observed between TNBS‐treated rats and corresponding controls (ethanol‐treated rats). No changes were observed in the abundance of α1 subunit Na+,K+‐ATPase in the proximal colon, terminal ileum and jejunum. The administration of IFN‐γ (50 000 U) 48 h before sacrifice reduced both Na+,K+‐ATPase activity and the abundance of α1 subunit Na+,K+‐ATPase in the proximal colon. Dexamethasone prevented colonic inflammation and decreases in proximal colonic Na+,K+‐ATPase activity in TNBS‐treated rats, but did not affect the INF‐γ‐induced decrease in colonic Na+,K+‐ATPase activity.

Conclusions:  The increase in ileal Na+,K+‐ATPase activity upstream to the lesioned colonic mucosa, where Na+,K+‐ATPase activity was markedly reduced, might indicate a compensatory process to counteract the decrease in water and electrolyte absorption at the colonic level. This decrease in colonic Na+,K+‐ATPase activity is likely not related to INF‐γ‐induced downregulation of Na+,K+‐ATPase.
The carboxy‐terminal tail region of human Cav2.1 (P/Q‐type) channel is not an essential determinant for its subcellular localization in cultured neurones
Authors: Hu Qiuping , Saegusa Hironao , Hayashi Yusuke , Tanabe Tsutomu
Published: January 2005

A recent report on the mechanism of synaptic targeting of Cav2.2 channel suggested that this process depends upon the presence of long C‐terminal tail and that protein interactions mediated by SH3‐binding and PDZ‐binding motifs in the tail region are important. To examine the possibility that C‐terminal tail of the Cav2.1 channel and the polyglutamine stretch therein are also involved in the mechanism for channel localization, we constructed several expression plasmids for human Cav2.1 channel tagged with enhanced green fluorescent protein (EGFP) and introduced them into mouse hippocampal neuronal culture. HC construct encodes short version of Cav2.1, and HS and HL encode Cav2.1 channel with a long C‐terminal tail, which contains polyglutamine tract of 13 (normal range) and 28 (SCA6 disease range) repeat units, respectively. Surprisingly, transfection with HC, HS, and HL gave essentially the same results: EGFP signal was observed in cell soma, dendrites, and the axon as well. Furthermore, mutation of the PDZ‐binding motif located at the C‐terminus of the long version of Cav2.1, by adding FLAG tag, did not affect the localization patterns of HS and HL as well. Therefore, the C‐terminal region is not indispensable for the subcellular localization of Cav2.1 channel, nor expansion of polyglutamine length affected the localization of the channel. Thus, it is possible that the localization mechanism of Cav2.1 channel is different from that of Cav2.2, though these channels share various structural and functional characteristics.
Rho‐kinase and myosin II activities are required for cell type and environment specific migration
Authors: Nakayama Masanori , Amano Mutsuki , Katsumi Akira , Kaneko Takako , Kawabata Saeko , Takefuji Mikito , Kaibuchi Kozo
Published: January 2005

Cell migration is important in the development of atherosclerotic lesions. Macrophages and smooth muscle cells migrate into the subendothelial space of arteries, leading to plaque formation. Long‐term inhibition of the activity of Rho‐kinase induces a regression of atherosclerotic coronary lesions, probably by preventing migration of macrophages and smooth muscle cells. Previous reports concerning the effect of Rho‐kinase inhibitors on cell migration are contradictory, however. We examined here the cell type specificity of Rho‐kinase inhibitors and found that migration of endothelial cells, macrophages, and smooth muscle cells was inhibited by treatment with Rho‐kinase inhibitors in a dose‐dependent fashion in a three‐dimensional migration assay, whereas that of fibroblasts and epithelial cells was not inhibited. Myosin II inhibitor prevented cell migration in a manner similar to Rho‐kinase inhibitors. In contrast, in a two‐dimensional migration assay, cell migration was not inhibited by Rho‐kinase or myosin II inhibitors for any of the cell types examined. Taken together, these results indicate that Rho‐kinase inhibitors suppress migration of specific cell types under specific conditions through the regulation of myosin II activity. Our findings suggest that Rho‐kinase is the therapeutic target of atherosclerosis accompanied with invasion by leukocytes and smooth muscle cells.
Aurora‐B and Rho‐kinase/ROCK, the two cleavage furrow kinases, independently regulate the progression of cytokinesis: possible existence of a novel cleavage furrow kinase phosphorylates ezrin/radixin/moesin (ERM)
Authors: Yokoyama Tomoya , Goto Hidemasa , Izawa Ichiro , Mizutani Hitoshi , Inagaki Masaki
Published: January 2005

Cytokinesis is regulated by several protein kinases, such as Aurora‐B and Rho‐kinase/ROCK. We have indicated that these two kinases are the cleavage furrow (CF) kinases that accumulate at the cleavage furrow and phosphorylate several intermediate filament (IF) proteins into two daughter cells. It has been reported that Aurora‐B phosphorylates MgcRacGAP to functionally convert to a RhoGAP during cytokinesis. Therefore, we investigated here the relationship between Aurora‐B and Rho‐kinase/ROCK in cytokinesis, by using small interfering RNA (siRNA) technique. Aurora‐B depletion did not alter the cleavage furrow‐specific localization of Rho‐kinase/ROCK and vice versa. Treatment of Aurora‐B or Rho‐kinase/ROCK siRNA increased multinucleate cells, and the effect of double depletion was additive. Aurora‐B depletion induced the reduction of cleavage furrow‐specific phosphorylation of vimentin at Ser72 but not vimentin at Ser71, myosin light chain (MLC) at Ser19, and myosin binding subunit of myosin phosphatase (MBS) at Ser852. In contrast, Rho‐kinase/ROCK depletion led to the reduction of cleavage furrow‐specific phosphorylation of MLC at Ser19, MBS at Ser852, and vimentin at Ser71 but not vimentin at Ser72. Cleavage furrow‐specific ezrin/radixin/moesin (ERM) phosphorylation was not altered in the Aurora‐B‐ and/or Rho‐kinase/ROCK‐depleted cells. In addition, C3 or toxin B treatment did not abolish ERM phosphorylation at the cleavage furrow in cells attaining cytokinesis. These results suggest that Aurora‐B and Rho‐kinase/ROCK regulate the progression of cytokinesis without communicating to each other, and there may exist a novel protein kinase which phosphorylates ERM at the cleavage furrow.
Interaction of anti‐proliferative protein Tob with poly(A)‐binding protein and inducible poly(A)‐binding protein: implication of Tob in translational control
Authors: Okochi Kentaro , Suzuki Toru , Inoue Jun‐ichiro , Matsuda Satoru , Yamamoto Tadashi
Published: January 2005

Tob is a member of an emerging family of anti‐proliferative proteins that suppress cell growth when over‐expressed. tob mRNA is highly expressed in anergic T cells and over‐expression of Tob suppresses transcription of interleukin‐2 (IL‐2) through its interaction with Smads. Here, we identified two types of cDNA clones coding for poly(A)‐binding protein (PABP) and inducible PABP (iPABP) by screening an expression cDNA library with the GST‐Tob probe. Co‐immunoprecipitation and GST‐pull down experiments showed that Tob associated with the carboxyl‐terminal region of iPABP. We then found that iPABP, like PABP, was involved in regulation of translation: iPABP enhanced translation of IL‐2 mRNA in vitro. The enhanced translation of IL‐2 mRNA required the 3′UTR and poly(A) sequences. Tob abrogated the enhancement of translation through its interaction with carboxyl‐terminal region of iPABP in vitro. Consistently, over‐expression of Tob in NIH3T3 cells, in which exogenous iPABP was stably expressed, resulted in suppression of IL‐2 production from the simultaneously transfected IL‐2 expression plasmid. Finally, Tob, whose expression was induced by anergic stimulation, was co‐immunoprecipitated with iPABP in human T cells. These findings suggest that Tob is involved in the translational suppression of IL‐2 mRNA in anergic T cells through its interaction with iPABP.
Semaphorin3A signalling is mediated via sequential Cdk5 and GSK3β phosphorylation of CRMP2: implication of common phosphorylating mechanism underlying axon guidance and Alzheimer's disease
Authors: Uchida Yutaka , Ohshima Toshio , Sasaki Yukio , Suzuki Hiromi , Yanai Shigeki , Yamashita Naoya , Nakamura Fumio , Takei Kohtaro , Ihara Yasuo , Mikoshiba Katsuhiko , Kolattukudy Papachan , Honnorat Jerome , Goshima Yoshio
Published: January 2005

Collapsin response mediating protein‐2 (CRMP2) has been identified as an intracellular protein mediating Semaphorin3A (Sema3A), a repulsive guidance molecule. In this study, we demonstrate that cyclin‐dependent kinase 5 (Cdk5) and glycogen synthase kinase 3β (GSK3β) plays a critical role in Sema3A signalling. In In vitro kinase assay, Cdk5 phosphorylated CRMP2 at Ser522, while GSK3β did not induce any phosphorylation of CRMP2. Phosphorylation by GSK3β was exclusively observed in Cdk5‐phosphorylated CRMP2, but barely in CRMP2T509A. These results indicate that Cdk5 primarily phosphorylates CRMP2 at Ser522 and GSK3β secondarily phosphorylates at Thr509. The dual‐phosphorylated CRMP2, but not non‐phosphorylated or single‐phosphorylated CRMP2, is recognized with the antibody 3F4, which is highly reactive with the neurofibrillary tangles of Alzheimer's disease. 3F4 recognized the CRMP2 in the wild‐type but not cdk5−/− mouse embryonic brain lysates. The phosphorylation of CRMP2 at Ser522 caused reduction of its affinity to tubulin. In dorsal root ganglion neurones, Sema3A stimulation enhanced the levels of the phosphorylated form of CRMP2 detected by 3F4. Over‐expression of CRMP2 mutant substituting either Ser522 or Thr509 to Ala attenuates Sema3A‐induced growth cone collapse response. These results suggest that the sequential phosphorylation of CRMP is an important process of Sema3A signalling and the same mechanism may have some relevance to the pathological aggregation of the microtubule‐associated proteins.
The Neurobiology of Social Bonds
Authors: Kendrick Keith M.
Published: January 2005

When released in the brain through giving birth or mating, the neuropeptides oxytocin and vasopressin are involved in promoting parent–offspring and monogamous bonds in animals such as sheep and voles. Bonds are only formed in species where receptors for these neuropeptides are highly expressed in dopamine‐producing reward centres. In humans, dysfunctions in these same systems can be associated with autism and, when we see people we love, these systems become activated
Potential benefit from using the αs1‐casein genotype information in a selection scheme for dairy goats
Authors: Sánchez A. , Ilahi H. , Manfredi E. , Serradilla J. M.
Published: January 2005

A stochastic approach is proposed to predict responses to selection when using αs1‐casein genotype information in a selection scheme of a Spanish breed of dairy goats. Two independent selection objectives were considered: protein yield (PY), where the major additive gene CSN1S1, which codes for αs1‐casein, has a small effect, and protein content (P%), where this gene has a large effect on performances. Significant differences in response between using and ignoring information on the major gene were observed only when the major gene has a large effect. The main result was in the case of P%, the total genetic gain obtained in the early generations of selection was maintained in the long‐term. Taking account of genotype information either in the evaluation model or in the selection criteria leads to a faster fixation of the favourable allele and a reduction of the total genetic variance over generations. The inbreeding rates varied across generations, the highest rates observed in later generations of selection and when the major gene has a large effect and its genotype was included in the genetic evaluation procedure. It is concluded that inclusion of the casein genotype as an additional selection criteria will improve gains for protein traits, in particular P%. Recommendations are also given in order to optimize the use of this molecular information in dairy goat selection programs.
A simulation study on the detection of causal mutations from F2 experiments
Authors: Varona L. , Gómez‐Raya L. , Rauw W.M. , Noguera J.L.
Published: January 2005

A simulation study has been performed to evaluate the power and the rate of false positives for the detection of causal mutations under two different models of analysis. We used an F2 design generated from an F0 population of five sires of line 1 and 40 dams of line 2 to produce an F1 population of 10 sires and 80 dams. Two different locations of the causal mutation and several frequencies of the mutations in the parental populations were considered. The first model included only the genetic configuration of the mutation, while the second model also included the probability of line origin given the neutral markers. Both models performed well when the mutation at the candidate gene was the causal mutation, although a greater power was obtained using the first model, because of its relative simplicity compared to the second one. However, when the candidate gene mutation was a neutral mutation, the second model presented a lower rate of false positives than the first. Moreover, in some cases the second model allowed distinction between the neutral and the causal mutation. The F2 design has a great power to detect quantitative trait loci provided by linkage disequilibrium, but also makes it difficult to discriminate between causal and neutral mutations. Therefore a high percentage of false positives can be expected. The limitations of F2 designs for discriminating between neutral and causal mutations are discussed.
An improved protocol for the production of AFLPTM markers in complex genomes by means of capillary electrophoresis
Authors: Papa R. , Troggio M. , Ajmone‐Marsan P. , Nonnis Marzano F.
Published: January 2005

The amplified fragment‐length polymorphism (AFLP) technology is a recently introduced method to investigate genomes of different complexity, from microbial to higher organisms. It is applied to purposes as diverse as identification of species, strain and varieties, investigation of genetic diversity within and between populations, simple and complex trait mapping, and construction of linkage and physical maps. This technology has been designed on the use of primers labelled with radioactivity and on AFLP fragment separation on sequencing gel. We show that the original EcoRI/TaqI AFLP protocol does not perform appropriately when transferred to fluorescent labelling and capillary electrophoresis (CE), and propose an improved protocol for the production of high‐quality AFLP markers in fish, rodents and artiodactyles by means of the Beckman‐Coulter CEQ2000 automatic DNA sequencer. In addition, we describe the procedure routinely used in our laboratory to obtain binary matrices from AFLP profiles with the aid of Genographer free‐share software (vers. 1.6.0, J.J. Benham, Montana State University), able to elaborate original fragment data and convert them to standard graphical formats for phylogenetic analyses. Comparison with radioactive AFLPs in goats confirmed the reliability of the protocol developed for CE. In fact, 107 fragments generated by two primer combinations and identified by both techniques were attributed the same scoring. Compared with traditional methods, the use of capillary systems and automated analysis increases data throughput and scoring reliability, decreasing the overall experimental error.
The value of prior information for detection of QTL affecting longitudinal traits: an example using Von Bertalanffy growth function
Authors: Varona L. , Gómez‐Raya L. , Rauw W.M. , Ovilo C. , Clop A. , Noguera J.L.
Published: January 2005

A Bayesian procedure is presented for detecting quantitative trait loci (QTL) affecting longitudinal traits. The statistical model assumes a QTL affecting the prior distribution of the parameters of a given production function, under a hierarchical Bayesian scheme. Marginal posterior distributions for the effects associated with the QTL are calculated using Markov chain Monte Carlo methods. Furthermore, the Bayesian analysis allows the use of some available relevant information that can improve the detection of the QTL substantially. To illustrate the procedure, an example of QTL detection using the Von Bertalanffy growth function is presented with a F2pig population bred from Iberian boars and Landrace sows. Animals of the F2population were genotyped for seven markers in chromosome 2 (SSC2). Two prior distributions for the mean effect of the parameters related with birth and adult weight were compared. On the one hand, vague prior distributions were used, and, on the other, there were assumed univariate Gaussian distributions that ensure biologically meaningful adult and birth weights on the posterior growth curves. Results from the second prior distribution supported the presence of QTL, by showing that individuals with both alleles of Iberian origin had lower rates of maturation. On the contrary, when vague priors were used, the procedure was not able to detect QTL.
Major histocompatibility complex locus DRA polymorphism in the endangered Sorraia horse and related breeds
Authors: Luís C. , Cothran E.G. , Oom M.M. , Bailey E.
Published: January 2005

The major histocompatibility complex (MHC) genes play well‐defined roles in eliciting immune responses and combating infectious diseases. This genetic system is among the most polymorphic. The extent of genetic variation within a population has been directly correlated with fitness for many traits. The MHC class II locus DRA polymorphism was analysed in the endangered Sorraia horse, two other Portuguese and four New World horse breeds considered to be historically close to the Sorraia. Comparison of the Sorraia with other breeds demonstrated less MHC variation among Sorraia horses. If DRA polymorphism provides greater disease resistance, selective breeding to increase MHC polymorphism may increase fitness of this population.
Fine mapping of a QTL for intramuscular fat on porcine chromosome 6 using combined linkage and linkage disequilibrium mapping
Authors: Uleberg E. , Widerøe I.S. , Grindflek E. , Szyda J. , Lien S. , Meuwissen T.H.E.
Published: January 2005

In this study data from a commercial Norwegian slaughter pig cross was analysed to confirm a previous reported quantitative trait locus (QTL) affecting intramuscular fat (IMF) on porcine chromosome 6. The data consisted of an old experiment, in which the QTL was previously detected, and new experimental data from the Norwegian slaughter pig cross. The old and new experimental data were analysed separately and together. A previously described method combining linkage and linkage disequilibrium analysis (LDLA) was used for the analysis, but this method assumes that all animals are descendants from a common base population, which is not realistic in a cross between different breeds. An adjusted version of the method, able to distinguish between different breeds in the cross, is presented here. Using the LDLA method, we were not able to confirm the QTL in the old experimental data, because the genetic variance could be explained by the polygenic effect. Analysis from the new experimental data did however detect the QTL, and analysing the data from both experiments together gave highly significant results for a QTL (p < 0.001) between markers SW1355 and SW1823. The main conclusion is therefore that the previously reported QTL for IMF on porcine chromosome 6 was confirmed within a 8.7‐cM confidence interval.
Frequency distribution of a Cys430Ser polymorphism in peroxisome proliferator‐activated receptor‐gamma coactivator‐1 (PPARGC1) gene sequence in Chinese and Western pig breeds
Authors: Kunej T. , Wu X.‐L. , Berlic T.M. , Michal J.J. , Jiang Z. , Dovc P.
Published: January 2005

Identification of major genes, that genetically impact fat tissue formation is important for successful selection of lean animals with good meat quality. Because of its central role in fat cell differentiation and muscle fibre type determination, PPARGC1 is a potential candidate gene affecting fattening traits and pig meat quality. In this study, a T/A substitution at position 1378 (GenBank accession no. AY346131) in the porcine PPARGC1 gene causing a Cys430Ser amino acid substitution at position 430 was genotyped on a total of 239 animals, including 101 from seven Chinese and 138 from six Western pig breeds. Bayesian analysis revealed that the mean frequency of allele T (Cys) was 92.64 ± 4.82% in Chinese pigs, and 45.99 ± 4.13% in Western pigs. The 95% interval of the posterior mean frequency of allele T was 0.82–1.00 in Chinese pigs and 0.38–0.54 in Western pigs, indicating these two groups of pigs diverged at this locus during genetic evolution of the breed. Because marked differences in fat and lean tissue deposition exist between Western and Chinese pig breeds, this Cys430Ser exchange in the PPARGC1 gene deserves further evaluation to determine its phenotypic effect on fattening and carcass traits in commercial pig populations.
Navigating the Transition to Junior High School: The Influence of Pre‐Transition Friendship and Self‐System Characteristics
Authors: Aikins Julie Wargo , Bierman Karen L. , Parker Jeffrey G.
Published: January 2005

The present study examined the influence of pre‐transition friendship and self‐system characteristics on junior high school transition adjustment in a sample of 111 early adolescent girls and boys. Transition adjustment was defined in terms of youth's post‐transition friendship quality, emotional distress, and school adjustment. Pre‐transition friendship characteristics were directly linked with both post‐transition friendship quality and school adjustment, while youth's expected possible selves, a component of youth's self‐system, made additional unique contributions to the prediction of youth's emotional distress and school adjustment. Results suggest the importance of developmentally salient friendship and self‐system characteristics in contributing to individual variability in transition adaptation.
The Implications of Having High‐achieving Versus Low‐achieving Friends: A Longitudinal Analysis
Authors: Altermatt Ellen Rydell , Pomerantz Eva M.
Published: January 2005

The present research examines the achievement‐related implications of establishing friendships with high‐achieving versus low‐achieving classmates. Fifth‐ , sixth‐ , and seventh‐grade students (N=929) participated. During the fall and spring semesters, the report card grades of children and their friends were obtained and children completed questionnaire measures of their self‐evaluative beliefs and preference for challenge. Results suggest that for low‐achieving students there are tradeoffs associated with establishing and maintaining friendships with high‐achieving classmates. Specifically, low achievers who established and maintained friendships with high‐achieving friends evaluated themselves less positively, but also performed better academically, than low achievers with similarly low‐achieving friends. Fewer tradeoffs emerged for high achievers.
Patterns of Affiliation with Delinquent Friends During Late Childhood and Early Adolescence: Correlates and Consequences
Authors: Vitaro Frank , Brendgen Mara , Wanner Brigitte
Published: January 2005

This study examined longitudinal patterns of affiliation with delinquent friends during late childhood and early adolescence, i.e., from ages 10 through 13, in a sample of 376 participants of both genders. Four groups with distinct affiliation profiles were found: an early affiliative group, a late affiliative group, a declining group (i.e., a group that affiliates with delinquent friends early on but much less so thereafter), and a group of children who did not affiliate with delinquent friends throughout the period covered in this study. There was also a fifth group of children who had no mutual friends throughout. The proportion of boys and girls varied in some groups but not in others. Participants’ own delinquency and depression trajectories as well as other behavior‐ , peer‐ , school‐ , and family‐related correlates were examined in association with group membership through the use of growth curves analysis. The results are discussed in light of prevalent theories about the role of delinquent friends with respect to externalizing and internalizing problems.
A Contextual Approach to the Development of Self‐regulatory Competencies: The Role of Maternal Unresponsivity and Toddlers’ Negative Affect in Stressful Situations
Authors: Rodriguez Monica L. , Ayduk Ozlem , Aber J. Lawrence , Mischel Walter , Sethi Anita , Shoda Yuichi
Published: January 2005

A prospective study examined the effects of maternal unresponsivity and of toddlers’ own negative affect on the child's subsequent ability to use effective attentional control strategies in preschool. Maternal and child behaviors were measured in situations that varied in the level of stress to test the hypothesis that behaviors in high stress situations would be more diagnostic of children's subsequent self‐regulatory behavior. As predicted, both maternal unresponsivity and toddlers’ negative affect, particularly in a high stress as opposed to a low stress situation, predicted children's later use of ineffective attentional control strategies. Similarly, maternal disengagement that occurred contingent to toddlers’ distress predicted ineffective attentional control strategies whereas maternal disengagement in response to toddlers’ non‐distress behaviors did not. The findings supported the utility of a contextual approach to understanding the impact of maternal and child characteristics on the development of self‐regulatory skills.
On the Importance of Comparative Research for the Understanding of Human Behavior and Development: A Reply to Gottlieb & Lickliter (2004)
Authors: Maestripieri Dario
Published: January 2005

Comparative behavioral research is important for a number of reasons and can contribute to the understanding of human behavior and development in many different ways. Research with animal models of human behavior and development can be a source not only of general principles and testable hypotheses but also of empirical information that may be extrapolated to humans.
Resting cortical brain activity and social behavior in higher functioning children with autism
Authors: Sutton Steven K. , Burnette Courtney P. , Mundy Peter C. , Meyer Jessica , Vaughan Amy , Sanders Chris , Yale Marygrace
Published: January 2005

Background:  Psychophysiological measurement of processes related to social behavior may be valuable for research on individual differences and subgroups among children with autism spectrum disorders (Coleman, 1987; Dawson, Klinger, Panagiotides, Lewy, & Castelloe, 1995; Modahl et al., 1998). In particular, recent research and theory suggests that measures of resting anterior EEG asymmetry reflect complex brain processes associated with individual differences in approach or avoidance motivation that may be associated with social and emotional interaction tendencies among children with autism.

Method:  This hypothesis was examined in a study of the relations among resting anterior asymmetry, social impairment, and social anxiety in 23 high functioning children with autism (HFA) and 20 controls (age range 9–14 years).

Results:  These groups were significantly different on the measures of anterior asymmetry, social symptoms and anxiety‐related measures. Moreover, HFA children who displayed right frontal asymmetry (RFA group) displayed more symptoms of social impairments and better visual analytic skills than did children who displayed left frontal asymmetry (LFA group). Alternatively, while the LFA group displayed fewer symptoms of social impairment they also reported greater levels of social anxiety, social stress, and lower satisfaction with interpersonal relations than did the RFA group.

Conclusions:  These observations indicate that anterior EEG asymmetry may be a marker of motivation and emotion processes that refract the autism taxon into important individual differences in social presentation among higher functioning children.