bluuebunny/crossref_metadata_2025 huggingface dataset:
Par‐4 inducible apoptosis in prostate cancer cells
Authors: Gurumurthy Sushma , Rangnekar Vivek M.
Published: January 2004

Prostate cancer is associated with the inability of prostatic epithelial cells to undergo apoptosis rather than with increased cell proliferation. Prostate apoptosis response‐4 (Par‐4) is a unique pro‐apoptotic molecule that is capable of selectively inducing apoptosis in cancer cells when over‐expressed, sensitizing the cells to diverse apoptotic stimuli and causing regression of tumors in animal models. This review discusses the salient functions of Par‐4 that can be harnessed to prostate cancer therapy. © 2004 Wiley‐Liss, Inc.
Characterization of Gicerin/MUC18/CD146 in the rat nervous system
Authors: Taira Eiichi , Kohama Keiko , Tsukamoto Yasuhiro , Okumura Shigeki , Miki Naomasa
Published: January 2004

Gicerin is a cell adhesion molecule of an immunoglobulin (Ig) superfamily isolated from a chicken. It shows homophilic and heterophilic binding activities and has two isoforms. s‐Gicerin which has small cytoplasmic domain and the same extracellular domain as l‐gicerin shows stronger cell adhesion activity. In the chick nervous system, gicerin expression is only observed in the developmental stage when neurons extend neurites and migrate. In other tissues, gicerin participates in the tissue regeneration or oncogenesis. In this report, we identified two isoforms of rat gicerin corresponding to chicken and we concluded that gicerin is a homologue of human CD146/MUC18/MCAM. Next we generated antibody to characterize a rat gicerin in the nervous system. Gicerin is expressed in the hippocampal cells, Purkinje cells, and sensory neurons of a spinal chord of an adult rat, while expressed most abundantly in the lung. In addition to this, its expression in the hippocampus was increased by electroconvulsive shock, suggesting some role in the mature nervous system. And we also showed neurite promotion activity of gicerin from hippocampal neurons. J. Cell. Physiol. 198: 377–387, 2004© 2003 Wiley‐Liss, Inc.
Normal skin wound and hypertrophic scar myofibroblasts have differential responses to apoptotic inductors
Authors: Moulin Véronique , Larochelle Sébastien , Langlois Céline , Thibault Isabelle , Lopez‐Vallé Carlos A. , Roy Michel
Published: January 2004

During wound healing, myofibroblasts play a central role in matrix formation and wound contraction. At the end of healing, there is evidence that myofibroblasts disappear via apoptotic pathways. Hypertrophic scars are a fibroproliferative disorder that leads to considerable morbidity. It has been postulated that a defect in myofibroblast apoptosis could be responsible for the pathological scar formation, but no evidence exists. We have isolated and cultured human normal wound (Wmyo) and hypertrophic scar (Hmyo) myofibroblasts and compared their basal apoptotic rates and their sensitivity to serum starvation and Fas antibody‐induced apoptosis to that obtained for dermal fibroblasts (Fb). A higher rate of apoptosis as evidenced by morphological criteria and a propidium iodide assay was observed for Wmyo in comparison to Fb and Hmyo. These results came along with a low level of the anti‐apoptotic proteins Bcl‐2 and BclxL in Wmyo, whereas there was an increase in the level of the pro‐apoptotic molecule Bax when compared to the results obtained for Fb and Hmyo. Hmyo showed a higher level of Bcl‐2 compared to Fb but no difference in the Bax or BclxL level. After serum starvation, Wmyo revealed an increased apoptotic rate, whereas Hmyo and Fb did not show any difference. Anti‐Fas treatment did not modify the levels of apoptosis but strongly increased the cell growth of Hmyo as compared to Wmyo. This is the first study presenting a broad vision of the apoptotic sensitivity of normal and pathological myofibroblasts. These results confirmed the hypothesis of defects in apoptosis and growth during pathological scar formation impeding myofibroblast disappearance at the end of healing. J. Cell. Physiol. 198: 350–358, 2004© 2003 Wiley‐Liss, Inc.
Simultaneous activation of several second messengers in hypoxia‐induced hyperpermeability of brain derived endothelial cells
Authors: Fischer Silvia , Wiesnet Marion , Marti Hugo H. , Renz Dieter , Schaper Wolfgang
Published: January 2004

In vivo, ischemia is known to damage the blood–brain barrier (BBB) leading to the development of vasogenic brain edema. Hypoxia‐induced vascular endothelial growth factor (VEGF) has been shown to be a key regulator of these permeability changes. However, the signaling pathways that underlie VEGF‐induced hyperpermeability are incompletely understood. In this study, we demonstrate that hypoxia‐ and VEGF‐induced permeability changes depend on activation of phospholipase Cγ (PLCγ), phosphatidylinositol 3‐kinase/Akt (PI3‐K/Akt), and protein kinase G (PKG). Inhibition of mitogen‐activated protein kinases (MAPK) and of the protein kinase C (PKC) did not affect permeability at all. Paralleling hypoxia‐ and VEGF‐induced permeability changes, localization of the tight junction proteins occludin, zonula occludens‐1 (ZO‐1), and ZO‐2 along the cell membrane changed from a continuous to a more discontinuous expression pattern during hypoxia. In particular, localization of ZO‐1 and ZO‐2 expression moved from the cell membrane to the cytoplasm and nucleus whereas occludin expression remained at the cell membrane. Inhibition of PLCγ, PI3‐kinase, and PKG abolished these hypoxia‐induced changes. These findings demonstrate that hypoxia and VEGF induce permeability through rearrangement of endothelial junctional proteins which involves activation of the PLCγ and PI3‐K/AKT pathway leading to the activation of PKG. J. Cell. Physiol. 198: 359–369, 2004© 2003 Wiley‐Liss, Inc.
Enterocytin: A new specific enterocyte marker bearing a B30.2‐like domain
Authors: Parnis Stéphane , Nicoletti Cendrine , Ollendorff Vincent , Massey‐Harroche Dominique
Published: January 2004

Enterocyte differentiation is correlated to the expression of specific proteins which only a few of them are identified. In this study, we characterize a new marker of enterocyte differentiation using monoclonal antibodies. We showed that small intestinal enterocytes specifically express a new 47 kDa protein named Enterocytin. Expression of this protein increase along the crypt‐villus axis and it is concentrated in the terminal web, lateral plasma membrane domain, and nucleus membrane of mature enterocytes. A 1.8‐kb cDNA of Enterocytin was isolated by expression cloning from a cDNA library of rabbit small intestine. The amino acid sequence obtained shows an N‐terminal region with a coiled‐coil structure and a B30.2‐like domain in the C‐terminus region. By co‐transfection and immunoprecipitation procedures on Cos cells, it was observed that the coiled‐coil domain is involved in the homodimerization of Enterocytin. In the human intestine, a similar 47 kDa protein was detected, exclusively in the small intestinal enterocytes. In addition, expression of this protein in Caco2 cells is correlated with the state of differentiation of these cells. The restricted expression of Enterocytin in the intestine and its localization in mature cells suggest that it may contribute to the differentiation processes and maintenance of the enterocytic polarity. J. Cell. Physiol. 198: 441–451, 2004© 2003 Wiley‐Liss, Inc.
ERK1/2 and JNKs, but not p38 kinase, are involved in reactive oxygen species‐mediated induction of osteopontin gene expression by angiotensin II and interleukin‐1β in adult rat cardiac fibroblasts
Authors: Xie Zhonglin , Singh Mahipal , Singh Krishna
Published: January 2004

Osteopontin (OPN), also called cytokine Eta‐1, expressed in the myocardium co‐incident with heart failure plays an important role in post myocardial infarction (MI) remodeling by promoting collagen synthesis and accumulation. Angiotensin II (Ang II) and inflammatory cytokines are increased in the heart following MI. We studied the involvement of mitogen‐activated protein kinases (ERK1/2, JNKs, p38 kinase) and reactive oxygen species (ROS) in Ang II‐ and cytokine‐induced OPN gene expression in adult rat cardiac fibroblasts. Ang II alone increased OPN mRNA (3.3 ± 0.3‐folds; P < 0.05; n = 7), while interleukin‐1β (IL‐1β), tumor necrosis factor (TNF‐α), and interferon‐γ (IFN‐γ) had no effect. A combination of Ang II with IL‐1β or TNF‐α, not IFN‐γ, increased OPN mRNA more than Ang II alone. Nitric oxide donor, S‐nitrosoacetylpenicillamine (SNAP), alone or in combination with Ang II had no effect. Diphenylene iodonium (DPI), inhibitor of NAD(P)H oxidase, and tiron, superoxide scavenger, inhibited Ang II‐ and Ang II+ IL‐1β‐stimulated increases in OPN mRNA. Ang II activated ERK1/2 within 5 min of treatment, not JNKs. IL‐1β activated ERK1/2 and JNKs within 15 min of treatment. A combination of Ang II and IL‐1β activated ERK1/2 within 5 min of treatment. None of these stimuli activated p38 kinase. DPI almost completely inhibited Ang II + IL‐1β‐stimulated activation of ERK1/2, while partially inhibiting JNKs. PD98059, ERK1/2 pathway inhibitor, and SP600125, JNKs inhibitor, partially inhibited Ang II + IL‐1β‐stimulated increases in OPN mRNA. A combination of PD98059 and SP600125 almost completely inhibited Ang II + IL‐1β‐stimulated increases in OPN mRNA. Thus, Ang II alone increases OPN expression, while IL‐1β and TNF‐α act synergistically with Ang II to increase OPN mRNA possibly via NO independent mechanisms. The synergistic increase in OPN mRNA involves ROS‐mediated activation of ERK1/2 and JNKs, not P38 kinase, pathways in cardiac fibroblasts. J. Cell. Physiol. 198: 399–407, 2004© 2003 Wiley‐Liss, Inc.
Differentiation of H9c2 cardiomyoblasts: The role of adenylate cyclase system
Authors: Pagano M. , Naviglio S. , Spina A. , Chiosi E. , Castoria G. , Romano M. , Sorrentino A. , Illiano F. , Illiano G.
Published: January 2004

The adenylate cyclase (AC)/cAMP/cAMP‐dependent protein kinase pathway controls many biological phenomena. The molecular mechanisms by which cAMP induces alternative commitment towards differentiation or proliferation are not still completely known. The differentiation of myoblast cell lines into myocytes/myotubes represents a well‐established model of skeletal muscle differentiation. We analyzed the AC/cAMP pathway during terminal differentiation of H9c2 myoblasts. When cultured in low‐serum containing medium, H9c2 myoblasts exit the cell cycle and differentiate into myocytes/myotubes. A key step of this process is the expression of myogenin, an essential transcription factor for the terminal differentiation into myocytes. During this phenomenon we observed a decrease in both cAMP levels and AC activity, which suggests a functional negative role of cAMP on the differentiation process of H9c2 cells. 8‐Br‐cAMP and other cAMP‐elevating agents, such as forskolin, IBMX, and isoproterenol, negatively affected skeletal muscle differentiation of H9c2 myoblasts. Both AC activity down‐regulation and intracellular cAMP reduction were accompanied by significant variations in the levels of membrane proteins belonging to the AC system (AC catalytic subunit, Gαi−1, Gαs). The functional relationship between intracellular cAMP content and protein levels of AC system is discussed. J. Cell. Physiol. 198: 408–416, 2004© 2003 Wiley‐Liss, Inc.
CREB Cooperates with BMP‐stimulated Smad signaling to enhance transcription of the Smad6 promoter
Authors: Ionescu Andreia M. , Drissi Hicham , Schwarz Edward M. , Kato Mitsuyasu , Puzas J. Edward , McCance Dennis J. , Rosier Randy N. , Zuscik Michael J. , O'Keefe Regis J.
Published: January 2004

Growth plate chondrocytes integrate a multitude of growth factor signals during maturation. PTHrP inhibits maturation through stimulation of PKA/CREB signaling while the bone morphogenetic proteins (BMPs) stimulate maturation through Smad mediated signaling. In this manuscript, we show that interactions between CREB and the BMP associated Smads are promoter specific, and demonstrate for the first time the requirement of CREB signaling for Smad mediated activation of a BMP responsive region of the Smad6 promoter. The 28 base pairs (bp) BMP responsive element of the Smad6 promoter contains an 11 bp Smad binding region and an adjacent 17 bp region in which we characterize a putative CRE site. PKA/CREB gain of function enhanced BMP stimulation of this reporter, while loss of CREB function diminished transcriptional activity. In contrast, ATF‐2 and AP‐1 transcription factors had minimal effects. Electrophoretic mobility shift assay (EMSA) confirmed CREB binding to the Smad6 promoter element. Mutations eliminating binding resulted in loss of transcriptional activity, while mutations that maintained CREB binding had continued reporter activation by CREB and BMP‐2. The Smad6 gene was similarly regulated by CREB. Dominant negative CREB reduced BMP‐2 stimulated Smad6 gene transcription by 50%, but markedly increased BMP‐2 mediated stimulation of colX and Ihh expression. In contrast, PTHrP which activates CREB signaling, blocked the stimulatory effect of BMP‐2 on colX and Ihh, but minimally inhibited the stimulatory effect of BMP on Smad6. These findings are the first to demonstrate a cooperative association between CREB and BMP regulated Smads in cells from vertebrates and demonstrate that promoter‐specific rather than generalized interactions between PKA/CREB and BMP signaling regulate gene expression in chondrocytes. J. Cell. Physiol. 198: 428–440, 2004© 2003 Wiley‐Liss, Inc.
Different roles of p38 MAPK and ERK in STI571‐induced multi‐lineage differentiation of K562 cells
Authors: Kohmura Kanoko , Miyakawa Yoshitaka , Kawai Yoko , Ikeda Yasuo , Kizaki Masahiro
Published: January 2004

STI571 is a specific tyrosine kinase inhibitor of Abl kinase. It was previously reported that STI571 induced hemoglobin synthesis in the chronic myelogenous leukemia (CML) cell line K562. However, its mechanisms remain unknown. In this study, we demonstrated that STI571 induced the phosphorylation of p38 mitogen‐activated protein kinase (MAPK) and dephosphorylation of extracellular signal‐regulated kinase (ERK) in K562 cells. In contrast, the phosphorylation of c‐Jun N‐terminal kinases (JNK) in K562 cells was not altered by STI571. We also found that STI571 induced all the myeloid (CD11b, CD13), megakaryocytic (CD41a, CD42), and erythroid (glycophorin‐A) markers on K562 cells. A p38 MAPK‐specific inhibitor, SB203580, inhibited the STI571‐induced multi‐lineage differentiation of K562 cells, indicating that p38 MAPK is crucial for this differentiation. In contrast, SB203580 did not overcome the inhibitory effect for proliferation of K562 cells, indicating that p38 MAPK activation by STI571 does not affect cell numbers. Among the hematopoietic transcription factors, the expression level of c‐myb mRNA was clearly downregulated after incubation with STI571 in K562 cells. STI571‐induced downregulation of c‐myb mRNA was prevented by the pretreatment of K562 cells by SB203580. Our data provides insights into how p38 MAPK and ERK pathways are involved in STI571‐induced differentiation of K562 cells. J. Cell. Physiol. 198: 370–376, 2004© 2003 Wiley‐Liss, Inc.
Recruitment and proliferation of T lymphocytes is supported by IFNγ‐ and TNFα‐activated human osteoblasts: Involvement of CD54 (ICAM‐1) and CD106 (VCAM‐1) adhesion molecules and CXCR3 chemokine receptor
Authors: Lisignoli Gina , Toneguzzi Stefania , Piacentini Anna , Cristino Sandra , Cattini Luca , Grassi Francesco , Facchini Andrea
Published: January 2004

The mechanism by which osteoblasts (OB) interact and modulate the phenotype and proliferation of T lymphocytes during inflammation is not well known. The effects of two regulatory cytokines, TNFα and IFNγ, on the expression of CD54 (ICAM‐1) and CD106 (VCAM‐1) adhesion molecules and the CXCR3 ligands (CXCL9, CXCL10, CXCL11), were assessed in a primary culture of human OB by real‐time PCR, flow cytometry, and immunohistochemistry. In addition, we functionally evaluated the recruitment and proliferation of T lymphocytes grown with resting or stimulated OB. According to the present data IFNγ, either alone or in combination with TNFα, significantly up‐regulates the expression of CD54 and CD106 and induces the expression and release of CXCL9, CXCL10, CXCL11 in OB. The supernatant of TNFα‐ and IFNγ‐activated OB induces the recruitment of T lymphocytes more significantly than stimulation by CXCR3 ligands. T lymphocyte proliferation is significantly enhanced by direct contact with TNFα‐ and IFNγ‐activated OB or by incubation with the supernatant of TNFα‐ and IFNγ‐activated OB. Blocking experiments with anti‐CD11a, anti‐CD49d, anti‐CXCR3, and Bordetella pertussis toxin demonstrate that adhesion molecules and the CXCR3 chemokine receptor play a key role in the proliferation of T lymphocytes. The present study demonstrates the involvement of adhesion molecules (CD11a and CD49d) and chemokine receptor (CXCR3) in the mechanism by which OB recruit, interact, and modulate T lymphocyte proliferation under inflammatory conditions. J. Cell. Physiol. 198: 388–398, 2004© 2003 Wiley‐Liss, Inc.
PDGF‐BB enhances α1β1 integrin‐mediated activation of the ERK/AP‐1 pathway involved in collagen matrix remodeling by rat mesangial cells
Authors: Kagami Shoji , Urushihara Maki , Kitamura Akiko , Kondo Shuji , Hisayama Tetsuhiro , Kitamura Masanori , Löster Klemens , Reutter Werner , Kuroda Yasuhiro
Published: January 2004

Platelet‐derived growth factor‐BB (PDGF‐BB) has been implicated in the pathogenesis of progressive glomerulonephritis (GN). Previous studies have reported that PDGF‐BB stimulates mesangial cells (MCs)‐induced collagen matrix remodeling through enhancement of α1β1 integrin‐dependent migratory activity. To determine the cell signaling pathway responsible for abnormal MC‐related mesangial matrix remodeling in progressive GN, we studied the involvement of the extracellular signal‐regulated kinase (ERK)/activator protein‐1 (AP‐1) pathway in PDGF‐BB‐enhanced collagen gel contraction. Western blotting and gel shift assay revealed that MC‐induced gel contraction resulted in ERK activation in parallel with that of AP‐1 binding, peaking at 4 h and lasting at least for 24 h. Application of the MEK inhibitor, U0126, and the c‐jun/AP‐1 inhibitor, curcumin, inhibited gel contraction and AP‐1 activity, respectively, dose dependently. PDGF‐BB enhanced not only gel contraction but ERK phosphorylation and AP‐1 activity by MCs. Marked inhibitory effects on PDGF‐BB‐induced gel contraction and ERK/AP‐1 activity were observed in the presence of either function blocking anti‐α1‐ or anti‐β1‐integrin antibody or U0126. Consistently, AP‐1‐inactive MCs expressing a dominant‐negative mutant of c‐jun showed a significant decrease of PDGF‐BB‐induced gel contraction as compared with mock‐transfected MCs. Finally, migration assay showed that ERK/AP‐1 activity is required for PDGF‐BB‐stimulated α1β1 integrin‐dependent MC migration to collagen I. These results indicated that PDGF‐BB enhances α1β1 integrin‐mediated collagen matrix reorganization through the activation of the ERK/AP‐1 pathway that is crucial for MC migration. We conclude that the ERK/AP‐1 pathway plays an important role in PDGF‐BB‐induced α1β1 integrin‐dependent collagen matrix remodeling; therefore, the inhibition of its pathway may provide a novel approach to regulate abnormal collagen matrix remodeling in progressive GN. J. Cell. Physiol. 198: 470–478, 2004© 2003 Wiley‐Liss, Inc.
ERK1/2 mediates TNF‐α‐induced matrix metalloproteinase‐9 expression in human vascular smooth muscle cells via the regulation of NF‐κB and AP‐1: Involvement of the ras dependent pathway
Authors: Moon Sung‐Kwon , Cha Byung‐Yoon , Kim Cheorl‐Ho
Published: January 2004

The expression of matrix metalloproteinase‐9 (MMP‐9) has been implicated in progression of atherosclerotic lesions. The role and importance of the signaling pathway in the transcriptional regulation of MMP‐9 in human aortic smooth muscle cells (HASMC) was examined. Tumor necrosis factor‐α (TNF‐α) stimulated the secretion of MMP‐9 in HASMC, as shown by zymography and immunoblot analysis. At the transcriptional levels, TNF‐α also stimulated the 5′‐flanking 710‐bp promoter activity of MMP‐9. Transcription factors NF‐κB binding site (−601) and AP‐1 binding site (−82) were identified as the cis‐elements for TNF‐α activation, as determined by gel shift assay and mutation analysis. Treatment with U0126, an inhibitor of the extracellular signal‐regulated kinase (ERK), significantly downregulated TNF‐α‐induced MMP‐9 expression and promoter activity, whereas the inactive analog U0124 had no effect. Furthermore, the transactivation of TNF‐α‐stimulated NF‐κB and AP‐1 was inhibited by U0126 treatment. Finally, the transient transfection of HASMC with dominant negative Ras (RasN17) suppressed TNF‐α‐induced ERK activity, MMP‐9 production, and promoter activity. Overexpression of RasN17 also abolished the TNF‐α‐stimulated NF‐κB and AP‐1 activity. In conclusion, the findings herein indicate the activation of the Ras/ERK pathway contributes to the induction of MMP‐9 expression in HASMC. In addition, the transcription factors NF‐κB and AP‐1 that are involved in the Ras/ERK‐mediated control of MMP‐9 regulation on HASMC in response to TNF‐α have now been identified. J. Cell. Physiol. 198: 417–427, 2004© 2003 Wiley‐Liss, Inc.
Induction of apoptosis by a hepatocyte conditioned medium
Authors: Bresgen Nikolaus , Rolinek R. , Hochleitner E. , Lottspeich F. , Eckl P.M.
Published: January 2004

Incubation of primary cultures of parenchymal hepatocytes in a conditioned medium (CM), collected over the first 3 h of serum‐free rat hepatocyte culture (CM0–3), induces a time dependent increase of the frequency of apoptotic cells which is accompanied by prominent changes of cell morphology. Short‐term treatment with CM0–3 for the first 3 h of culture is sufficient to significantly (P < 0.05) increase the frequency of apoptotic cells, however, the effect is more pronounced upon long‐term treatment. Although apoptosis induction by CM0–3 is independent of the timepoint when cultivation in CM0–3 starts, our results suggest that the sensitivity for apoptosis induction by CM0–3 is increased during the phase of attachment. Purification of CM0–3 resulted in a fraction which significantly (P < 0.05) induced apoptosis at concentrations ≥10 ng/ml. Exposure of cultures to concentrations ≥1 μg/ml of purified CM0–3 gave rise to a prominent cytotoxic effect as indicated by the massive occurrence of necrotic cells. Biochemical analysis showed that the purified fraction of CM0–3 contains acidic ferritins with molecular weight of 23 and 43 kDa. Strikingly, both share homologies with placental isoferritins (PLF), for which growth inhibitory and immunosuppressive effects have been demonstrated by several investigations. Therefore, our results provide evidence that rat hepatocytes produce PLF or PLF‐related acidic isoferritins which are able to induce apoptosis. J. Cell. Physiol. 198: 452–460, 2004© 2003 Wiley‐Liss, Inc.
Kinase suppressor of RAS (KSR) amplifies the differentiation signal provided by low concentrations 1,25‐dihydroxyvitamin D3
Authors: Wang Xuening , Studzinski George P.
Published: January 2004

The activity of kinase suppressor of ras (KSR), a kinase or a molecular scaffold upstream from Raf‐1, is involved in the MEK/ERK MAP kinase cascade which can signal cell growth, survival, or differentiation, depending on the cellular context. We provide evidence here that KSR is upregulated in HL60 cells undergoing differentiation induced by low (0.3–3 nM) concentrations of 1,25‐dihydroxyvitamin D3 (1,25D3), and an antisense oligo (AS), but not a sense oligo, to KSR inhibits this differentiation. The inhibition of differentiation by AS–KSR oligo was less apparent when the concentration of 1,25D3 was increased, suggesting that at the higher concentrations of 1,25D3 KSR is not essential for the signaling of the differentiated phenotype. The reduced differentiation of HL60 cells exposed to AS–KSR was paralleled by reduced phosphorylation of Raf‐1 Ser 259, and of p90RSK, used here as read‐out for MAPK cascade activity. Conversely, ectopic expression of Flag‐tagged wild type KSR potentiated the differentiation‐inducing effects of low concentrations of 1,25D3. Additional data suggest that the kinase activity of KSR is required for these effects, as transfection of a kinase inactive KSR construct did not significantly increase the 1,25D3‐induced differentiation. Enzyme assays performed with KSR immunoprecipitated from 1,25D3‐treated cells showed kinase activity when recombinant Raf‐1 was used as the substrate, but not when the 1,25D3‐treated cells were pretreated with AS–KSR oligos. Taken together, these data suggest that KSR participates in signaling of monocytic differentiation by augmenting the strength of the signal transmitted through Raf‐1 to downstream targets. J. Cell. Physiol. 198: 333–342, 2004© 2003 Wiley‐Liss, Inc.
New basic discoveries and frontiers in diagnosis, prognosis and prediction of response to therapy in human thyroid, urinary bladder, and prostate tumors
Authors: Giordano Giovan Giacomo , Tagliabue Elda , Pupa Serenella M.
Published: January 2004

The fourth edition of this workshop mainly focused on three different human oncotypes, which included thyroid, urinary bladder, and prostate tumors as clinical models to gain new basic knowledge on tumor diagnosis, prognosis, and treatment. At the previous editions (Giordano et al., 2000, J Cell Physiol 183:284–287; Giordano et al., 2001, J Cell Physiol 188:274–280; Giordano et al., 2002, J Cell Physiol 191:362–365), leaders in the fields of pathology, clinical oncology, and basic research presented and discussed the most recent and prevalent findings in such neoplasms from a basic and clinical perspective. A concept that has been widely proposed is that the analysis of intrinsic biological factors displayed by primary tumors may be a valid method for diagnosing different neoplasias and for measuring both their aggressiveness and response to therapy. To date, however, no single prognostic factor, such as oncogenes, suppressor genes, or genes involved in the control of the cell cycle and/or apoptosis has yet proven to be potent enough to be used in clinical practice as a prognostic and predictive factor. The new possibility to simultaneously analyze the expression of the complete repertoire of human genes and a large number of proteins could offer a new scenario in tumor classification, allowing for the formulation of a list of genes able to define a “signature” of tumor outcome. Moreover, starting from data obtained from biomolecular tumor analyses, it has been demonstrated that with this approach, it is also possible to design future therapeutic strategies. J. Cell. Physiol. 198: 343–349, 2004© 2003 Wiley‐Liss, Inc.
Exposure to 900 MHz electromagnetic field induces an unbalance between pro‐apoptotic and pro‐survival signals in T‐lymphoblastoid leukemia CCRF‐CEM cells
Authors: Marinelli F. , La Sala D. , Cicciotti G. , Cattini L. , Trimarchi C. , Putti S. , Zamparelli A. , Giuliani L. , Tomassetti G. , Cinti Caterina
Published: January 2004

The original article to which this Erratum was published in J. Cell. Physiol. 198:324–332, 2004

It has been recently established that low‐frequency electromagnetic field (EMFs) exposure induces biological changes and could be associated with increased incidence of cancer, while the issue remains unresolved as to whether high‐frequency EMFs can have hazardous effect on health. Epidemiological studies on association between childhood cancers, particularly leukemia and brain cancer, and exposure to low‐ and high‐frequency EMF suggested an etiological role of EMFs in inducing adverse health effects. To investigate whether exposure to high‐frequency EMFs could affect in vitro cell survival, we cultured acute T‐lymphoblastoid leukemia cells (CCRF‐CEM) in the presence of unmodulated 900 MHz EMF, generated by a transverse electromagnetic (TEM) cell, at various exposure times. We evaluated the effects of high‐frequency EMF on cell growth rate and apoptosis induction, by cell viability (MTT) test, FACS analysis and DNA ladder, and we investigated pro‐apoptotic and pro‐survival signaling pathways possibly involved as a function of exposure time by Western blot analysis. At short exposure times (2–12 h), unmodulated 900 MHz EMF induced DNA breaks and early activation of both p53‐dependent and ‐independent apoptotic pathways while longer continuous exposure (24–48 h) determined silencing of pro‐apoptotic signals and activation of genes involved in both intracellular (Bcl‐2) and extracellular (Ras and Akt1) pro‐survival signaling. Overall our results indicate that exposure to 900 MHz continuous wave, after inducing an early self‐defense response triggered by DNA damage, could confer to the survivor CCRF‐CEM cells a further advantage to survive and proliferate. J. Cell. Physiol. 198: 324–332, 2004. © 2003 Wiley‐Liss, Inc.
Visualization of vesicle transport along and between distinct pathways in neurites of living cells
Authors: Schütz Gerhard J. , Axmann Markus , Freudenthaler Susanne , Schindler Hansgeorg , Kandror Kostya , Roder John C. , Jeromin Andreas
Published: January 2004

Trafficking of secretory vesicles along neurites of PC12 cells was visualized by 2D and 3D real‐time imaging using fluorescence microscopy. Vesicle motion along distinct pathways was directly seen. From an overlay of individual pathways, the underlying cytoskeletal filament could be imaged at a subwavelength resolution. Continuous vesicle transport was interrupted by periods of diffusive motion with concomitant pathway changes. Statistical analysis shows that such interruptions were distributed stochastically along the filament, indicating a limited processivity of motor proteins also in a cellular context. Periods of diffusive motion facilitated the interaction with actively transported vesicles. Frequent associations and dissociations of vesicles have been observed consistently, pointing to a functional relevance of vesicle cotransport. Microsc. Res. Tech. 63:159–167, 2004. © 2004 Wiley‐Liss, Inc.
Comparison of structural and hemostatic properties of the poly‐N‐acetyl glucosamine Syvek Patch with products containing chitosan
Authors: Fischer Thomas H. , Connolly Raymond , Thatte Hemant S. , Schwaitzberg Steven S.
Published: January 2004

Polysaccharides are becoming increasingly developed as therapeutics and medical products, as the new field of Glycomics expands. Glycosaminoglycans that contain N‐acetyl glucosamine constituents have been the focus of research leading to medical devices. A new hemostatic bandage, the Syvek Patch, has been introduced in the recent past for the control of bleeding at vascular access sites in interventional cardiology and radiology procedures. This product consists of poly‐N‐acetyl glucosamine (pGlcNAc) isolated in a unique fiber crystalline structural form from the large‐scale culture and processing of a marine diatom. The Syvek pGlcNAc fiber material has chemical, physical, and biological properties that result in its favorable performance as a hemostat. Two new products, the Clo‐Sur PAD and ChitoSeal, have recently become available also as patch hemostats. These two products both use chitosan, another N‐acetyl glucosamine containing glycosaminoglycan, as their active ingredient. Structural, chemical, and biological comparisons of Syvek pGlcNAc and chitosan reveal a number of important differences. Syvek pGlcNAc fibers contain ∼50 fully acetylated, high molecular weight pGlcNAc molecules in a crystalline, three‐dimensional beta structure array, and are insoluble. Chitosan is a low molecular weight mixed amorphous cationic polymer with no regular structure as a solid, and is water‐soluble taking on a random coil configuration when in solution. These structural dissimilarities result in differences in the hemostatic properties of the two materials. Syvek pGlcNAc is able to significantly reduce the in vitro fibrin clot formation time of platelet‐rich plasma samples and has the ability to cause aggregation of red blood cells in vitro. Chitosan is no better than gauze or other controls in these in vitro assays. The Syvek Patch is able to control the bleeding and cause hemostasis in a coagulopathic swine spleen‐bleeding animal model 100% of the time, whereas Clo‐Sur PAD was completely unsuccessful (0%) and ChitoSeal (25%) was worse than a gauze pad control (50%) in the same model. Syvek pGlcNAc fibers have structural and chemical properties that provide a unique basis for their ability to interact with blood components to cause hemostasis. Chitosan does not have the same properties and capabilities. Microsc. Res. Tech. 63:168–174, 2004. © 2004 Wiley‐Liss, Inc.
Perisynaptic Schwann cells of the vertebrate motor endplate bear modified cilia
Authors: Voigt Tilman , Dauber Wolfgang , Kohler Ulrike
Published: January 2004

Perisynaptic Schwann cells (PSCs), descendants of the myelinating Schwann cells, cover the axon terminal of the vertebrate motor endplate of the skeletal muscle fiber. PSCs are assumed to support the function of the axon terminal. This function suggests a net material transport in the direction of the axon terminal. Morphologically it is to be expected that these cells have a cytoskeleton aligned to the axon terminal. Investigations clarifying this statement have not yet been undertaken. From previous investigations we know, however, that the PSCs have a microtubule‐organizing center, which is a part of this cytoskeleton. The centrioles of the organizing center may also participate in the formation of a modified cilium structure whose function is unknown. In the present investigation, characteristic ultrastructural features of the modified cilium structure and its relationship to the Golgi apparatus and the axon terminal are presented. A function for the modified cilium structure is discussed. Microsc. Res. Tech. 63:149–154, 2004. © 2004 Wiley‐Liss, Inc.
Ultrastructural features of bone marrow cells from patients with acquired sideroblastic anemia
Authors: Djaldetti Meir , Bergman Michael , Salman Hertzel , Cohen Amos M. , Bessler Hanna
Published: January 2004

The ultrastructural findings of the bone marrow cells from 15 patients with acquired sideroblastic anemia are presented. The red cell precursors from all patients showed the presence of electron‐dense material in the mitochondria, representing most probably iron deposits. A great number of these mitochondria were completely destroyed. The erythropoietic precursors from one of the patients showed markedly elongated mitochondria that measured up to 3 μm. In addition numerous cytoplasmic vacuoles were observed. The red cell precursors from 60% of the patients showed signs of dyserythropoiesis, such as incomplete nuclear division and nuclear distortion. The polymorphonuclears from 47% of the patients presented nuclear abnormalities expressed as nuclear bridges, appendices, and blebs. In addition, phagocytosis of red blood cells was observed. The results of the study underline the advantages of the transmission electron microscope examination in visualization of intricate alterations in hematopoietic cells that cannot be detected with a light microscope. Microsc. Res. Tech. 63:155–158, 2004. © 2004 Wiley‐Liss, Inc.
The use of optical parametric oscillator for harmonic generation and two‐photon UV fluorescence microscopy
Authors: Kao Fu‐Jen
Published: January 2004

Ultrafast lasers have found increasing use in scanning optical microscopy due to their very high peak power in generating multiphoton excitations. A mode‐locked Ti:sapphire laser is often employed for such purposes. Together with a synchronously pumped optical parametric oscillator (OPO), the spectral range available can be extended to 1,050–1,300 nm. This broader range available greatly facilitates the excitation of second harmonic generation (SHG) and third harmonic generation (THG) due to better satisfaction of phase matching condition that is achieved with a longer excitation wavelength. Dental sections are then investigated with the contrasts from harmonic generation. In addition, through intra‐cavity doubling wavelengths from 525–650 nm are made available for effective two‐photon (2‐p) excitation with the equivalent photon energy in the UVB range (290–320 nm) and beyond. This new capacity allows UV (auto‐) fluorescence excitation and imaging, for example, from some amino acids, such as tyrosine, tryptophan, and glycine. Microsc. Res. Tech. 63:175–181, 2004. © 2004 Wiley‐Liss, Inc.
From head to tail: The myoseptal system in basal actinopterygians
Authors: Gemballa Sven , Röder Katrin
Published: January 2004

Experimental studies indicated that myomeres play several functional roles during swimming. Some of the functions in question are thought to change rostrocaudally, e.g., anterior myomeres are thought to generate forces, whereas posterior myomeres are thought to transmit forces. In order to determine whether these putative functions are reflected in myoseptal morphology we carried out an analysis of the myoseptal system that includes epaxial and hypaxial myosepta of all body regions for the first time. We combined clearing and staining, microdissections, polarized light microscopy, SEM technique, and length measurements of myoseptal parts to reveal the spatial arrangement, collagen fiber architecture, and rostrocaudal gradients of myosepta. We included representatives of the four basal actinopterygian clades to evaluate our findings in an evolutionary and in a functional context. Our comparison revealed a set of actinopterygian groundplan features. This includes a set of specifically arranged myoseptal tendons (epineural, epipleural, lateral, and myorhabdoid tendons) in all epaxial and postanal hypaxial myosepta. Only preanal hypaxial myosepta lack tendons and exclusively consist of mediolateral fibers. Laterally, myosepta generally align with the helically wound fibers of the dermis in order not to limit the body's maximum curvature. Medially, the relationship of myosepta to vertebrae clearly differs from a 1:1 relationship : A myoseptum attaches to the anterior margin of a vertebra, turns caudally, and traverses at least three vertebrae in an almost horizontal orientation in all body regions. By this arrangement, horizontal multiple layers of myosepta are formed along the trunk dorsal and ventral to the horizontal septum. Due to their reinforcement by epineural or epipleural tendons, these multiple layers are hypothesized to resist the radial expansion of underlying muscle fibers and thus contribute to modulation of body stiffness. Rostrocaudally, a dorsoventral symmetry of epaxial and hypaxial myosepta in terms of spatial arrangement and collagen fiber architecture is gradually developed towards the postanal region. Furthermore, the rostrocaudal extension of myosepta measured between anterior and posterior cones gradually increases. This myoseptal region is reinforced by longitudinal fibers of lateral tendons. Furthermore, the percentage of connective tissue in a cross section increases. These morphological data indicate that posterior myosepta are equipped for multisegmental force transmission towards the caudal fin. Anteriormost myosepta have reinforced and elongated dorsal posterior cones. They are adequately designed to transmit epaxial muscular forces to the neurocranium in order to cause its elevation during suction feeding. J. Morphol. 259:155–171, 2004. © 2003 Wiley‐Liss, Inc.
Phylogenetic comparison of serotonin‐immunoreactive neurons in representatives of the Chilopoda, Diplopoda, and Chelicerata: Implications for arthropod relationships
Authors: Harzsch Steffen
Published: January 2004

The phylogenetic relationships within the Arthropoda have been discussed controversially for more than a century. Comparative studies on structure and development of the nervous system have contributed important arguments to this discussion. Arthropods have individually identifiable neurons that can be used as characters in phylogenetic studies. In the present report, the arrangement of serotonin‐immunoreactive neurons in the ventral nerve cord was examined in seven representatives of the Chelicerata, Chilopoda, and Diplopoda. The goal of this analysis was to determine whether number, arrangement, and axonal morphology of the serotonergic neurons in these groups are similar to the pattern found in representatives of the Hexapoda and Crustacea, as explored in a previous study. The results indicate that the pattern in the seven species examined here does not correspond to that present in the Hexapoda and Crustacea. In particular, the pattern in Chilopoda and Diplopoda is clearly different from that of the Hexapoda. The hexapodan pattern most closely resembles that of the Crustacea. These findings are discussed with regard to recent reports on the mechanisms of neurogenesis in these taxa. Furthermore, the proposed ground patterns of the various groups are reconstructed and the characters are plotted on two competing hypotheses of arthropod phylogeny, the traditional Tracheata hypothesis and an alternative hypothesis derived from molecular and recent morphological data, the Tetraconata concept. The data discussed in this article moderately support the Tetraconata hypothesis. J. Morphol. 259:198–213, 2004. © 2003 Wiley‐Liss, Inc.
Placental ontogeny of the Tasmanian scincid lizard, Niveoscincus ocellatus (Reptilia: Squamata)
Authors: Stewart James R. , Thompson Michael B.
Published: January 2004

A prominent scenario for the evolution of reptilian placentation infers that placentotrophy arose by gradual modification of a simple vascular chorioallantoic placenta to a complex structure with a specialized region for nutrient transfer. The structure of the chorioallantoic placenta of Niveoscincus ocellatus, apparently described originally from a single embryonic stage, was interpreted as a transitional evolutionary type that provided support for the model. Recently, N. ocellatus has been found to be as placentotrophic as species with complex chorioallantoic placentae containing a specialized region called a placentome. We studied placental development in N. ocellatus and confirmed that the chorioallantoic placenta lacks specializations found in species with a placentome. We also found that this species has a specialized omphaloplacenta. The chorioallantoic placenta is confined to the region adjacent to the embryo by a membrane, similar to that found in some other viviparous skinks, that divides the egg into embryonic and abembryonic hemispheres. We term this structure the “inter‐omphalopleuric” membrane. The position of this membrane in N. ocellatus is closer to the embryonic pole of the egg than to the abembryonic pole and thus the surface area of the omphaloplacenta is greater than that of the chorioallantoic placenta. In addition, the omphaloplacenta is regionally diversified and more complex histologically than the chorioallantoic placenta. An impressive and unusual feature of the omphaloplacenta of N. ocellatus is the development of extensive overlapping folds in the embryonic component of mid‐gestation embryos. The histological complexity and extensive folding of the omphaloplacenta make this a likely site of placental transfer of nutrients in this species. J. Morphol. 259:214–237, 2004. © 2003 Wiley‐Liss, Inc.
Sexual dimorphism in the craniofacial growth of the guinea pig (Cavia porcellus)
Authors: Farmer Meredith A. , German Rebecca Z.
Published: January 2004

Variation between the sexes during ontogeny is frequently overlooked in discussions of the phylogenetic patterns of adult sexual dimorphism. Different growth trajectories can produce identical degrees and direction of adult dimorphism and the possibility exists that similarities in adults may be the result of differing growth patterns, suggesting independent evolutionary pathways among species to the seemingly identical adult morphology. We quantified the sexual dimorphism in craniofacial skeletal growth of Cavia porcellus, the guinea pig, using longitudinally collected radiographs. Guinea pigs have male‐biased sexual dimorphism in size and in growth parameters, despite literature reports to the contrary. These results, analyzed with equivalent data for five species of rodents, and two outgroups representing similarly sized mammals, a rabbit and a marsupial, indicate that some aspects of sexual differences in growth follow phylogenetic lines, while others are a function of whether the species has male‐ or female‐biased dimorphism. J. Morphol. 259:172–181, 2004. © 2003 Wiley‐Liss, Inc.
Synthesis of interkeratin matrix in differentiating lizard epidermis: An ultrastructural autoradiographic study after injection of tritiated proline and histidine
Authors: Alibardi Lorenzo
Published: January 2004

During epidermal differentiation in mammals, keratins and keratin‐associated matrix proteins rich in histidine are synthesized to produce a corneous layer. Little is known about interkeratin proteins in nonmammalian vertebrates, especially in reptiles. Using ultrastructural autoradiography after injection of tritiated proline or histidine, the cytological process of synthesis of beta‐keratin and interkeratin material was studied during differentiation of the epidermis of lizards. Proline is mainly incorporated in newly synthesized beta‐keratin in beta‐cells, and less in oberhautchen cells. Labeling is mainly seen among ribosomes within 30 min postinjection and appears in beta‐keratin packets or long filaments 1–3 h later. Beta‐keratin appears as an electron‐pale matrix material that completely replaces alpha‐keratin filaments in cells of the beta‐layer. Tritiated histidine is mainly incorporated into keratohyalin‐like granules of the clear layer, in dense keratin bundles of the oberhautchen layer, and also in dense keratin filaments of the alpha and lacunar layer. The detailed ultrastructural study shows that histidine‐labeling is localized over a dense amorphous material associated with keratin filaments or in keratohyalin‐like granules. Large keratohyalin‐like granules take up labeled material at 5–22 h postinjection of tritiated histidine. This suggests that histidine is utilized for the synthesis of keratins and keratin‐associated matrix material in alpha‐keratinizing cells and in oberhautchen cells. As oberhautchen cells fuse with subjacent beta‐cells to form a syncytium, two changes occur : incorporation of tritiated histidine, but uptake of proline increases. The incorporation of tritiated histidine in oberhautchen cells lowers after merging with cells of the beta‐layer, whereas instead proline uptake increases. In beta‐cells histidine‐labeling is lower and randomly distributed over the cytoplasm and beta‐keratin filaments. Thus, change in histidine uptake somehow indicates the transition from alpha‐ to beta‐keratogenesis. This study indicates that a functional stratum corneum in the epidermis of amniotes originates only after the association of matrix and corneous cell envelope proteins with the original keratin scaffold of keratinocytes. J. Morphol. 259:182–197, 2004. © 2003 Wiley‐Liss, Inc.