bluuebunny/crossref_metadata_2025 huggingface dataset:
Chelerythrin activates caspase‐8, downregulates FLIP long and short, and overcomes resistance to tumour necrosis factor‐related apoptosis‐inducing ligand in KG1a cells
Authors: Platzbecker Uwe , Ward Jessica L. , Deeg H. Joachim
Published: July 2003

Summary. KG1a cells (CD34+/38–) express FAS and TRAIL (tumour‐necrosis‐factor‐related apoptosis‐inducing ligand) receptors but are resistant to FAS‐ligand and TRAIL/APO2‐L (apoptosis antigen‐2 ligand)‐induced apoptosis. KG1a cells are sensitized to FAS‐induced apoptosis by chelerythrin, an inhibitor of protein kinase C (PKC). As cytoplasmatic adaptor molecules of FAS, e.g. FLIP {Fas‐associated death domain protein (FADD)‐like interleukin 1 beta‐converting enzyme [FLICE (caspase‐8)‐inhibitory protein]}, also modulate TRAIL signals, we determined whether chelerythrin affected TRAIL‐mediated apoptosis. Chelerythrin by itself induced apoptosis in KG1a cells, and apoptosis was associated with activation of caspase‐8. While TRAIL alone failed to activate caspase‐8 or induce apoptosis, the addition of TRAIL to chelerythrin‐treated cells significantly enhanced cleavage of caspase‐8 and apoptosis. Chelerythrin‐pretreated KG1a cells showed decreased phosphorylation of protein kinase C (PKC)‐ζ and downregulation of both FLIP long and FLIP short proteins. Downregulation of FLIP and induction of apoptosis were partially abrogated by pretreatment with the specific caspase‐8 inhibitor, Z‐IETD‐FMK. The decrease in FLIP protein expression induced by chelerythrin was accompanied by a progressive increase in mRNA levels of both FLIP long and FLIP short. CD34+ precursors from normal human marrow were also sensitive to chelerythrin but, in contrast to KG1a cells, were not sensitized to TRAIL‐mediated apoptosis. Thus, resistance to TRAIL‐induced apoptosis in leukaemic KG1a cells but not in normal CD34+ precursors was overcome in the presence of chelerythrin. The mechanism appeared to involve inhibition of PKC. Central targets were FLIP long and FLIP short, and their interactions with caspase‐8. Whether such a pathway can be exploited to selectively target leukaemic progenitor cells remains to be determined.
Rituximab reduces relapse risk after allogeneic and autologous stem cell transplantation in patients with high‐risk aggressive non‐Hodgkin's lymphoma
Authors: Shimoni Avichai , Hardan Izhar , Avigdor Abraham , Yeshurun Moshe , Raanani Pia , Ben‐Bassat Isaac , Nagler Arnon
Published: July 2003

Summary. High‐dose chemotherapy and autologous stem cell transplantation (SCT) have limited success in patients with refractory aggressive lymphoma. Allogeneic SCT may offer some advantage in this setting by providing graft‐versus‐lymphoma effect, but the relapse risk remains substantial. In this study, we evaluated the safety and efficacy of rituximab administration after SCT in patients at high‐risk for post‐transplant relapse, in order to reduce relapse risk. Twenty‐eight patients were included with the intent to treat them with rituximab after autologous (n = 16) or allogeneic (n = 12) SCT. Twenty‐four were given rituximab starting a median of 47 d post SCT. Three died of SCT complications prior to therapy. Nine patients not achieving a complete remission (CR) post SCT converted to CR with rituximab and with the onset of graft‐versus‐host disease (GVHD) in three. With a median follow‐up of 12 months (range, 3–33 months) the estimated 2‐year overall survival and disease‐free survival was 85 ± 7% and 55 ± 13% respectively. When only those patients who were actually treated are analysed, these rates were 95 ± 7% and 64 ± 13% respectively. The relapse risk was 35 ± 14%. Seven patients had recurrent neutropenia episodes associated with severe hypogammaglobulinaemia, which were further prevented with intravenous immunoglobulin. None of the 10 allogeneic SCT recipients treated with rituximab had severe GVHD. Rituximab may be an effective adjuvant therapy after SCT to reduce the relapse rate and improve the outcome in high‐risk aggressive lymphoma. Larger scale comparative trials are necessary to better define its role in SCT.
Efficacy and safety of darbepoetin alfa in anaemic patients with lymphoproliferative malignancies: a randomized, double‐blind, placebo‐controlled study
Authors: Hedenus Michael , Adriansson Magnus , Miguel Jesus San , Kramer Mark H. H. , Schipperus Martin R. , Juvonen Eeva , Taylor Kerry , Belch Andrew , Altés Albert , Martinelli Giovanni , Watson David , Matcham James , Rossi Gregory , Littlewood Timothy J.
Published: July 2003

Summary. This phase 3, randomized, double‐blind, placebo‐controlled study was designed to evaluate the efficacy and safety of darbepoetin alfa in anaemic patients with lymphoproliferative malignancies. Patients (n = 344) with lymphoma or myeloma received darbepoetin alfa 2·25 μg/kg or placebo s.c., once weekly for 12 weeks. The percentage of patients achieving a haemoglobin response was significantly higher in the darbepoetin alfa group (60%) than in the placebo group (18%) (P < 0·001), regardless of baseline endogenous erythropoietin level. However, increased responsiveness was observed in patients with lower baseline erythropoietin levels. Darbepoetin alfa also resulted in higher mean changes in haemoglobin than placebo from baseline to the last value during the treatment phase (1·80 g/dl vs 0·19 g/dl) and after 12 weeks of treatment (2·66 g/dl vs 0·69 g/dl). A significantly lower percentage of patients in the darbepoetin alfa group received red blood cell transfusions than in the placebo group (P < 0·001). The efficacy of darbepoetin alfa was consistent for patients with lymphoma or myeloma. Improvements in quality of life were also observed with darbepoetin alfa. The overall safety profile of darbepoetin alfa was consistent with that expected for this patient population. Darbepoetin alfa significantly increased haemoglobin and reduced red blood cell transfusions in patients with lymphoproliferative malignancies receiving chemotherapy.
Patterns of bone marrow involvement in 58 patients presenting primary splenic marginal zone lymphoma with or without circulating villous lymphocytes
Authors: Audouin Josée , Le Tourneau Agnès , Molina Thierry , Camilleri‐Broët Sophie , Adida Colette , Comperat Eva , Benattar Laurence , Delmer Alain , Devidas Alain , Rio Bernard , Diebold Jacques
Published: July 2003

Summary. We studied 86 bone marrow biopsies (BMB) from 58 patients presenting with primary splenic marginal zone lymphoma (PSMZL). In 42 patients, a splenectomy was performed which enabled a histopathological diagnosis. In these patients, 44 biopsies were carried out before, and 25 after, splenectomy. In 16 recently observed patients, 17 BMB led to PSMZL diagnosis, and these patients were treated without splenectomy. Seven different patterns of infiltrates were recognized: intravascular, interstitial, nodular, massive, plasmacytic mimicking myeloma and transformation into large B‐cell lymphoma (DLBCL). The association of an intravascular infiltrate and nodules with a germinal centre and/or a marginal zone favoured a diagnosis of MZL. Immunohistochemistry demonstrated the expression of B cell‐associated antigens and, in 40% of the patients, a monotypic lymphoplasmacytic cell component. These patients often presented a serum M component and autoimmune disorders. In the past, such cases have been diagnosed as lymphoplasmacytic lymphoma. BM involvement was present in all patients. Successive biopsies showed progression and, after chemotherapy, a slight decrease in infiltrates. Transformation into DLBCL occurred in 11 of 34 patients. The patterns described are not specific for PSMZL and occur also in primary nodal MZL and, more rarely, in MALT‐type lymphoma.
Impact of granulocyte colony‐stimulating factor (CSF) and granulocyte–macrophage CSF in patients with malignant lymphoma: a systematic review
Authors: Bohlius Julia , Reiser Marcel , Schwarzer Guido , Engert Andreas
Published: July 2003

Summary. The granulopoiesis‐stimulating factors, granulocyte colony‐stimulating factor (G‐CSF) and granulocyte–macrophage colony‐stimulating factor (GM‐CSF), are used to prevent neutropenia and febrile neutropenia in patients with malignant lymphoma. The question as to whether G‐CSF/GM‐CSF improves dose‐intensity, tumour response and overall survival (OS) has not yet been answered. As the results from single studies are inconclusive, a systematic review was performed to determine the effectiveness of G‐CSF/GM‐CSF. Randomized controlled trials comparing prophylaxis with G‐CSF/GM‐CSF versus no prophylaxis in adult patients with malignant lymphoma undergoing conventional chemotherapy were included. Medical databases (Cochrane Library, Medline, Embase) and conference proceedings were searched. All authors were contacted to obtain missing data. We included 11 studies making a total of 1434 patients. Compared with no prophylaxis, G‐CSF/GM‐CSF significantly reduced the relative risk (RR) for neutropenia {RR 0·64 [95% confidence interval (CI) 0·55–0·75]} febrile neutropenia (RR 0·74 [95% CI 0·62–0·89]) and infection (RR 0·74 [95% CI 0·64–0·85]). G‐CSF/GM‐CSF did not decrease infection‐related mortality (RR 2·07 [95% CI 0·81–5·34]), improve complete remission (CR) (RR 1·06 [95% CI 0·96–1·16]) or OS (HR 0·98 [95% CI 0·81–1·18]). In conclusion, G‐CSF/GM‐CSF given during conventional chemotherapy in malignant lymphoma patients reduced the RR of neutropenia, febrile neutropenia and infection. However, there is no evidence that G‐CSF/GM‐CSF improved CR and OS in this clinical setting.
Clinical heterogeneity in chronic myeloid leukaemia reflecting biological diversity in normal persons
Authors: Gordon Myrtle Y. , Marley Stephen B. , Apperley Jane F. , Marin David , Kaeda Jaspal , Szydlo Richard , Goldman John M.
Published: July 2003

Summary. The molecular basis of chronic myeloid leukaemia (CML) is well defined and highly consistent, yet prognosis varies considerably. This could reflect the biological diversity occurring in normal populations. We used a colony replating assay to measure the proliferative capacity of progenitor cells from 211 CML patients and 86 normal persons. Results were expressed as the frequency distributions of the proliferation index (PI) for individual cases. Normal PI values varied among individuals but were reproducible in individuals. The PIs for CML patients were moderately but significantly greater (P = 0·004) than normal values, consistent with increased progenitor cell proliferation in CML. Exposure of CML progenitor cells to the Abl‐kinase inhibitor imatinib shifted their PI towards the normal range, implicating p210BCR–ABL. as a cause of the increased PI. The PIs of CML patients were higher than those of their human leucocyte antigen (HLA)‐matched siblings PI (P = 0·003) and patient PI increased exponentially with sibling PI (r = 0·77; P = 0·001), but not with the PI values of HLA‐matched unrelated individuals (P = 0·66). Finally, patients with high‐risk prognostic scores (according to the Sokal or Hasford systems) had a significantly higher PI than those with low risk scores (P = 0·01 and 0·03 respectively). We conclude that heterogeneity in the CML patient population is analogous to the constitutional diversity in normal subjects.
Phosphatase and tensin homologue phosphorylation in the C‐terminal regulatory domain is frequently observed in acute myeloid leukaemia and associated with poor clinical outcome
Authors: Cheong June‐Won , Eom Ju In , Maeng Ho‐Young , Lee Seung Tae , Hahn Jee Sook , Ko Yun Woong , Min Yoo Hong
Published: July 2003

Summary. Phosphorylation of PTEN (phosphatase and tensin homologue) affects PTEN protein stability and function. In this study, phosphorylated PTEN (pPTEN) was observed in 45 (73·8%) of 61 cases with acute myeloid leukaemia (AML). Phosphorylation of Akt and its downstream molecules [FKHR; Forkhead (Drosophila) homologue 1; and GSK‐3β; glycogen synthase kinase 3 beta] was significantly associated with pPTEN (P < 0·001). The complete remission rates were not different with respect to pPTEN, but overall survival was significantly shorter in patients with pPTEN (P < 0·05). Constitutive PTEN phosphorylation may add insight into the molecular pathogenesis of AML, and may be a new parameter for an unfavourable outcome.
Routine blood counts in children with acute lymphoblastic leukaemia after completion of therapy: are they necessary?
Authors: Gandhi Minal , Rao Kanchana , Chua Siew , Saha Vaskar , Lilleyman John , Shankar Ananth
Published: July 2003

Summary. Children who have completed treatment for acute lymphoblastic leukaemia (ALL) are commonly followed up for the first 5 years with regular full blood counts (FBCs) to monitor for relapse of disease. There is little evidence to suggest that this practice improves the detection rate of unexpected relapse. Surveillance FBCs, performed on 43 children with relapsed ALL between 1990 and 1999, were analysed. Of the 42 relapses in children off therapy, only two were detected by an abnormal FBC. Routine FBCs in asymptomatic children off therapy lacks specificity in detecting unexpected relapses and maybe safely discontinued.
Prothrombotic coagulation defects and cardiovascular risk factors in young women with acute myocardial infarction
Authors: Tanis Bea C. , Bloemenkamp Daisy G. M. , Van Den Bosch Maurice A. A. J. , Kemmeren Jeanet M. , Algra Ale , Van De Graaf Yolanda , Rosendaal Frits R.
Published: July 2003

Summary. We investigated the effect of prothrombotic coagulation defects in combination with smoking and other conventional risk factors on the risk of myocardial infarction in young women. In 217 women with a first myocardial infarction before the age of 50 years and 763 healthy control women from a population‐based case–control study, factor V Leiden and prothrombin 20210A status were determined. Data on major cardiovascular risk factors and oral contraceptive use were combined with the presence or absence of these prothrombotic mutations, and compared between patients and controls. The overall odds ratio for myocardial infarction in the presence of a coagulation defect was 1·1 [95% confidence interval (CI) 0·6–1·9]. The combination of a prothrombotic mutation and current smoking increased the risk of myocardial infarction 12‐fold (95% CI 5·7–27) compared with non‐smokers without a coagulation defect. Among women who smoked cigarettes, factor V Leiden presence versus absence increased the risk of myocardial infarction by 2·0 (95% CI 0·9–4·6), and prothrombin 20210A presence versus absence had an odds ratio of 1·0 (95% CI 0·3–3·5). We conclude that factor V Leiden and prothrombin 20210A do not add substantially to the overall risk of myocardial infarction in young women. However, in women who smoke, the presence of factor V Leiden increased the risk of myocardial infarction twofold.
MDS‐type abnormalities within myeloma signature karyotype (MM‐MDS): only 13% 1‐year survival despite tandem transplants
Authors: Jacobson Joth , Barlogie Bart , Shaughnessy John , Drach Johannes , Tricot Guido , Fassas Athanasios , Zangari Maurizio , Giroux Dori , Crowley John , Hough Aubrey , Sawyer Jeff
Published: July 2003

Summary.Cytogenetic abnormalities (CA), especially of chromosome 13, have been used to identify a subgroup of previously untreated multiple myeloma (MM) patients with very poor prognosis despite high‐dose therapy (HDT). We examined the prognostic implications of CA in 1000 MM patients receiving melphalan‐based tandem autotransplants (median follow‐up, 5 years). Negative consequences for both overall survival (OS) and event‐free survival (EFS) in the presence of any CA were confirmed, especially when detected within 3 months of HDT. In the context of standard prognostic factors (SPF), ‘MM‐MDS’ (MM karyotype that contains, in addition, CA typical of MDS) imparted a poor OS and EFS, after adjusting for any CA and all individual CA. One‐year mortality was also high, especially for the MM‐MDS subgroup with trisomy 8 within a MM signature karyotype (87%vs34% in its absence,P < 0·001). No patient remained event free 5 years post transplant in the presence of these baseline high‐risk CA. However, certain trisomies (e.g. chromosomes 7 and 9) and del 20 had favourable clinical consequences. The higher risk that is associated with CA compared with SPF justifies routine cytogenetic studies in all patients with MM at diagnosis and whenever additional treatment decisions are considered, such as in planning HDT either for initial response consolidation, at the time of primary unresponsiveness to induction therapy, or at relapse.
A new staging system for multiple myeloma patients based on the Southwest Oncology Group (SWOG) experience
Authors: Jacobson Joth L. , Hussein Mohamad A. , Barlogie Bart , Durie Brian G. M. , Crowley John J.
Published: July 2003

Summary.We aimed to develop and evaluate a staging system for multiple myeloma (MM) based on easily obtained laboratory measures. The Durie–Salmon stage is most commonly used and is an effective system of patient stratification for clinical trial research. However, the criteria are complex and many laboratory parameters are required to properly stage patients. In this analysis, we focused on two common measures with prognostic importance in MM: serum β2 microglobulin (β2m) and serum albumin. Pre‐study data on 1555 previously untreated MM patients enrolled on four recent South‐west Oncology Group (SWOG) phase III trials were used in the analysis. Staging models were developed and validated using regression tree methods for survival outcomes. SWOG stages were defined as: stage 1, β2m < 2·5 mg/l (14% of patients, median overall survival of 55 months); stage 2, 2·5 ≤ β2m < 5·5 (43% of patients, median overall survival of 40 months); stage 3, β2m ≥ 5·5 and albumin ≥ 30 g/l (32% of patients, median overall survival of 24 months); and stage 4, β2m ≥ 5·5 and albumin < 30 g/l (11% of patients and median overall survival of 16 months). This staging scheme was also predictive of event‐free survival, first‐year mortality and long‐term (≥ 5 years) event‐free survival. We conclude that although the SWOG stage does not represent a new prognostic marker for MM (cytogenetics, FISH), it could provide a simple alternative to the Durie–Salmon stage for patients with previously untreated MM. Additional evaluation in other MM patient populations is needed to confirm results.
Direct selection of human bone marrow mesenchymal stem cells using an anti‐CD49a antibody reveals their CD45med,low phenotype
Authors: Deschaseaux Frederic , Gindraux Florelle , Saadi Rafika , Obert Laurent , Chalmers David , Herve Patrick
Published: July 2003

Summary. Human bone marrow mesenchymal stem cells (MSC) generate, via a fibroblast colony‐forming unit (CFU‐F), osteo‐chondroblastic cells as well as adipocytes and stromacytes. To date, these stem cells are isolated indirectly using a cell culture method and phenotyped as CD45 negative while the in vivo counterparts are undetermined. Our aim was to develop a direct selection method and to determine the phenotype of the MSC isolated in this way. Mesenchymal cells were selected with anti‐CD49a and/or anti‐CD45 antibodies using either flow cytometry or a magnetic beads method. All CFU‐F were always detected in the small population of CD49a‐positive cells. These CFU retained their differentiation potential and gave rise to osteo‐chondroblastic cells, adipocytes and stromacytes. Phenotypic studies on uncultured cells revealed a CD45med,low, CD34low, HLA‐II– cell population. Flow cytometry cell sorting showed that MSC with CFU‐F potential were obtained only from a CD49a+/CD45med,low population. In addition, when cultured, they clearly became CD45–, CD34–, HLA‐II–, CD49a+. These results confirmed that MSC can be directly selected easily from human bone marrow using magnetic beads without altering their differentiation potential. These cells expressed mildly the haematopoietic marker CD45, which was dramatically downregulated by in vitro culture. The expression of CD45 coupled to CD49a thus enabled direct selection of the MSC.
Fine needle aspiration (FNA) cyt_logy in tuberculous lymphadenitis
Authors: ERSÖZ  , POLAT  , SERIN  , SOYLU  , DEMIRCAN
Published: July 2003

ersöz c., polat a., serin m. s., soylu l. and demircan o. (1998) Cyt_pathology9, 201–207

Fine needle aspiration (FNA) cyt_logy in tuberculous lymphadenitis

Sixty‐three lymph node aspirates were screened and 32 aspirates revealing granulomatous lymphadenitis with or without caseation necrosis were re‐evaluated. The most characteristic morphological features among these cases were epithelioid cell clusters with or without caseation necrosis. When clusters were thick, careful observation of the periphery of the clusters helped to find epithelioid cells. Caseation necrosis revealed a typical macroscopic and microscopic appearance. Ziehl–Neelsen staining was negative in all smears and histological sections. Polymerase chain reaction (PCR) amplification technique was applied to 23 of the cases in which the cyt_logical diagnoses were consistent with tuberculosis. Mycobacterium tuberculosis was demonstrated in 19 (82.60%) cases. In conclusion: (i) it is necessary to perform several aspirations from different sites of the enlarged lymph node; (ii) the diagnosis of ‘granulomatous lymphadenitis, consistent with tuberculosis’ can be given, even though the acid‐fast stains are negative; (iii) additional techniques such as PCR give supportive information; (iv) an open biopsy is recommended if there is a discrepancy with the clinical impression.
The phosphatidylinositol‐3 kinase (PI3K)‐Akt pathway suppresses neurite branch formation in NGF‐treated PC12 cells
Authors: Higuchi Maiko , Onishi Keisuke , Masuyama Norihisa , Gotoh Yukiko
Published: July 2003

Background:  Previous studies have shown that phosphatidylinositol‐3 kinase (PI3K) plays an important role in NGF (nerve growth factor)‐induced neurite elongation. However, the roles of the PI3K pathway in neurite branch formation were not fully understood. Also, it was not clear where the PI3K pathway is activated during branch formation.

Results:  We found that the treatment of PC12 cells with the PI3K inhibitor LY294002 resulted in a marked increase in the number of neurite branch points, suggesting a suppressive role of PI3K in neurite branch formation. Expression of a constitutively active form of Akt, a downstream effector of PI3K, decreased the number of branch points, whereas that of a dominant‐negative form of Akt increased it. In contrast, inhibition of neither Rac, mTOR nor GSK3, other effectors of PI3K, promoted branch formation. Importantly, the phosphorylated form of endogenous Akt was localized at the tips of growth cones, but devoid of small branches in NGF‐treated PC12 cells. A GFP‐fusion protein of the plekstrin‐homology (PH) domain of Akt was also localized at the tips of growth cones.

Conclusions:  The PI3K‐Akt pathway thus plays a key role in suppression of neurite branch formation in NGF‐treated PC12 cells.

working model for the regulation of neuritogenesis in PC12 cells. PI3K may mediate NGF regulation of neuritogenesis via two pathways. Rac induces neurite elongation and branch formation. Akt induces neurite elongation, but prevents branch formation.

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A tumour‐associated DEAD‐box protein, rck/p54 exhibits RNA unwinding activity toward c‐myc RNAs in vitro
Authors: Akao Yukihiro , Yoshida Hitoshi , Matsumoto Kenji , Matsui Tsutomu , Hogetu Keita , Tanaka Nobuo , Usukura Jiro
Published: July 2003

Background:  The rck/p54 protein of 473 amino acids belongs to the family of DEAD‐box/putative RNA helicase proteins. DEAD‐box proteins have been implicated in a wide variety of cellular processes ranging from the initiation of protein synthesis and ribosome biosynthesis to premRNA splicing by means of modifying the RNA structure. Our previous data suggested that rck/p54 positively affected the translation initiation of c‐myc mRNA.

Results:  The data obtained from morphological studies and surface plasmon resonance assays clearly indicated that the protein specifically bound to c‐myc RNA transcripts (RNAs) and exhibited RNA unwinding activity toward c‐myc RNAs in the presence of ATP in vitro. Experiments using a deletion mutant of rck/p54 retaining only its N‐terminal 289 amino acids demonstrated that the deleted C‐terminal 184 amino acid domain is involved in the RNA unwinding activity.

Conclusion:  These findings strongly suggest that rck/p54 may play an important role in translation initiation by restructuring mRNAs even in the cell and contribute to carcinogenesis.
Negative regulation of Wnt signalling by HMG2L1, a novel NLK‐binding protein
Authors: Yamada Misato , Ohkawara Bisei , Ichimura Naoya , Hyodo‐Miura Junko , Urushiyama Seiichi , Shirakabe Kyoko , Shibuya Hiroshi
Published: July 2003

Background:  Wnt signalling plays a critical role in many developmental processes and tumorigenesis. Wnt/β‐catenin signalling induces the stabilization of cytosolic β‐catenin, which interacts with TCF/LEF‐1 transcription factors, thereby inducing expression of Wnt‐target genes. Recent evidence suggests that a specific MAP kinase pathway involving the MAP kinase kinase kinase TAK1 and the MAP kinase NLK counteract Wnt signalling.

Results:  To identify NLK‐interacting proteins, we performed yeast two‐hybrid screening. We isolated the gene HMG2L1 and showed that injection of Xenopus HMG2L1 (xHMG2L1) mRNA into Xenopus embryos inhibited Wnt/β‐catenin‐induced axis duplication and expression of Wnt/β‐catenin target genes. Moreover, xHMG2L1 inhibited β‐catenin‐stimulated transcriptional activity in mammalian cells.

Conclusions:  Our findings indicate that xHMG2L1 may negatively regulate Wnt/β‐catenin signalling, and that xHMG2L1 may play a role in early Xenopus development together with NLK.
Sphingosine 1‐phosphate promotes cell migration through the activation of Cdc42 in Edg‐6/S1P4‐expressing cells
Authors: Kohno Takayuki , Matsuyuki Hirofumi , Inagaki Yuichi , Igarashi Yasuyuki
Published: July 2003

Abstracts

Background:  Sphingosine 1‐phosphate (Sph‐1‐P) is a bioactive lipid mediator released from activated platelets, which regulates diverse signal transduction pathways via cell surface receptors. Recent studies have revealed that the seven‐transmembrane‐spanning receptors, Edg‐1, Edg‐3, Edg‐5, Edg‐6 and Edg‐8 are specific Sph‐1‐P receptors. Northern blot analysis has demonstrated that Edg‐6 is expressed in lymphocyte‐containing tissues such as spleen and lung. Little is known about the molecular mechanisms of Edg‐6 functions, probably because of the difficulties in expressing Edg‐6 on the cell surface.

Results:  Here, our studies revealed that N‐terminal FLAG‐tagged Edg‐6 or Edg‐6‐GFP fusion protein was expressed in the endoplasmic reticulum, but was not expressed on the cell surface. On the other hand, C‐terminally tagged Edg‐6 or both N‐terminally and C‐terminally tagged Edg‐6 was able to localize to the cell surface. Using these cells, we found that Sph‐1‐P induced cell migration through cell surface‐expressed Edg‐6 in a pertussis toxin‐sensitive manner. This motility was mediated through the activation of a member of the Rho family of small GTPases, Cdc42.

Conclusion:  These results support a role for Sph‐1‐P signalling via Edg‐6 in the pathways involved in cell motility.
A new staphylococcal sigma factor in the conserved gene cassette: functional significance and implication for the evolutionary processes
Authors: Morikawa Kazuya , Inose Yumiko , Okamura Hideyuki , Maruyama Atsushi , Hayashi Hideo , Takeyasu Kunio , Ohta Toshiko
Published: July 2003

Background:  Staphylococcus aureus is a major human pathogen and causes a serious hospital infection due to the acquired multidrug resistance. Unlike the well‐studied bacteria such as Escherichia coli and Bacillus subtilis, which have seven and 18 sigma factors, respectively, only two sigma factors have been known for S. aureus. We searched for possible sigma factor genes by examining the S. aureus genome with a special attention to the gene arrangement around the sigma factor genes of a close relative, B. subtilis.

Results:  A new sigma factor gene was identified in Staphylococcus. The gene constituted a conserved gene cluster with other genes including translation‐ and transcription‐related genes. Phylogenetic analysis and comparison of the gene sequences among species indicated that the staphylococcal sigma factor originated from a common ancestor of B. subtilis SigH. An over‐expression of this sigma factor in S. aureus resulted in a drastic induction of the expression of the com operons that encode proteins required for the natural genetic competence.

Conclusions:  We demonstrated that the newly identified staphylococcal sigma factor participated in a regulatory network of transcription that controlled the genetic competence genes. In our phylogenetic tree, the factor was classified as a single group with a common function.
Temperature compensation and temperature resetting of circadian rhythms in mammalian cultured fibroblasts
Authors: Tsuchiya Yoshiki , Akashi Makoto , Nishida Eisuke
Published: July 2003

Background:  Circadian rhythms control many physiological processes. One of characteristic properties of circadian rhythms is insensitivity to temperature, called temperature compensation. Although this temperature‐insensitive property has repeatedly been observed mainly in circadian output rhythms, temperature effect on autoregulatory feedback loops of clock gene expression, the rhythm‐generating mechanisms, has not been fully investigated.

Results:  We show first that the circadian oscillation of clock gene expression in NIH3T3 fibroblasts, which is induced by TPA (12‐O‐tetradecanoylphorbol‐13‐acetate) treatment, is strongly temperature‐compensated over the temperature range of 33−42 °C. We then show that heat treatment at 42 °C is able to trigger circadian oscillation of clock gene expression in NIH3T3 cells. This 42 °C heat treatment, unlike serum shock or TPA treatment, did not induce immediate expression of mPer1 mRNA, suggesting the existence of several different resetting mechanisms.

Conclusions:  This is the first demonstration of temperature compensation of the rhythm‐generating core feedback loops of clock gene expression in mammalian cultured cells. It is possible that cells in the periphery could sense the change of ambient temperature as a resetting cue and that the whole organism thus could be entrained rapidly at dawn, in cooperation with the resetting mechanism by light.
Incidence of patent furcal accessory canals in permanent molars of a Turkish population
Authors: Haznedaroğlu F. , Ersev H. , Odabaşı H. , Yetkin G. , Batur B. , Aşçı S. , İşsever H.
Published: July 2003

Aim  To determine the incidence of patent furcal accessory canals in permanent molars of a Turkish population.

Methodology  Two‐hundred extracted teeth consisting of 50 maxillary first molars, 50 maxillary second molars, 50 mandibular first molars and 50 mandibular second molars from Turkish patients attending the Oral Surgery Department of the Faculty of Dentistry, İstanbul University, İstanbul, Turkey, were included in the study. After preparation of access cavities and removal of pulp tissue, the teeth were stored in 5.25% sodium hypochlorite for 1 h. Following double‐sealing of the access cavities, all tooth surfaces except the furcation regions were covered with nail varnish. The teeth were stored in 0.5% basic fuchsin for 1 week. The teeth were sectioned at the cemento‐enamel junction and the presence of patent furcal canals was established by examining the pulp chamber floor with a stereomicroscope (10×) to determine staining.

Results  Patent furcal accessory canals were detected in 24% of maxillary first molars, 16% of maxillary second molars, 24% of mandibular first molars, and 20% of mandibular second molars. No statistically significant differences were found between the tooth types.

Conclusions  In a Turkish population, the incidence of patent furcal accessory canals on the pulp chamber floor of maxillary and mandibular first and second molars ranged between 16 and 24%.
A prospective clinical study of Mineral Trioxide Aggregate and IRM when used as root‐end filling materials in endodontic surgery
Authors: Chong B. S. , Pitt Ford T. R. , Hudson M. B.
Published: July 2003

Aim  To assess the success rate of the root‐end filling material, Mineral Trioxide Aggregate (MTA).

Methodology  Referred adult patients were recruited using strict entry criteria and randomly allocated to receive MTA or IRM. A standardized surgical technique was employed: the root end was resected perpendicularly and a root‐end cavity was prepared ultrasonically and filled. A radiograph taken immediately after surgery was compared with those taken at 12 and 24 months. Customised film holders and the paralleling technique were used; radiographs were assessed by two trained observers using agreed criteria. The results from 122 patients (58 in IRM group, 64 in MTA group) after 12 months and 108 patients (47 in IRM group, 61 in MTA group) for the 24‐month review period were analysed using the χ2 test.

Results  The highest number of teeth with complete healing at both times was observed when MTA was used. When the numbers of teeth with complete and incomplete (scar) healing, and those with uncertain and unsatisfactory healing were combined, the success rate for MTA was higher (84% after 12 months, 92% after 24 months) compared with IRM (76% after 12 months, 87% after 24 months). However, statistical analysis showed no significant difference in success between materials (P > 0.05) at both 12 and 24 months.

Conclusions  In this study, the use of MTA as a root‐end filling material resulted in a high success rate that was not significantly better than that obtained using IRM.
Fluid movement along the coronal two‐thirds of root fillings placed by three different gutta‐percha techniques
Authors: Wu M.‐K. , Van Der Sluis L. W. M. , Ardila C. N. , Wesselink P. R.
Published: July 2003

Aim  To compare fluid movement (FM) along the coronal two‐thirds of gutta percha/sealer root fillings placed by three different techniques.

Methodology  Three groups consisting of the roots of mandibular incisors were instrumented and obturated by cold lateral compaction (LC), warm vertical compaction (VC) or the single‐cone technique (SC), using RoekoSeal Automix (RSA) as the sealer. The apical 4 mm of each root filling was removed, and FM along the remaining 7 mm of the root filling was measured.

Results  The VC group displayed more FM than the other two groups (P = 0.023). No significant difference in FM was found between the LC and SC groups (P = 0.629).

Conclusions  The coronal two‐thirds of the VC root fillings did not prevent FM when RSA sealer was used.
The location of the cementodentinal junction in single‐rooted mandibular first premolars from Egyptian and Saudi patients: a histological study
Authors: Saad A. Y. , Al‐Yahya A. S.
Published: July 2003

Aim  To determine the location of the cementodentinal junction (CDJ) in mandibular first premolars from Egyptian and Saudi patients.

Methodology  One hundred and twenty‐two extracted single‐rooted mandibular first premolars (68 Egyptian; 54 Saudi) were examined histologically. Half of the teeth were fixed, decalcified, embedded in paraffin, mesio‐distally sectioned and stained with H&E, whilst the other half were ground with a stone prior to microscopic evaluation. Measurements of the location of the CDJ were made parallel to the long axis of the teeth from the external surface of the root apex on the mesial and distal sides of the canal. Measurements were statistically analysed using two‐way anova of repeated‐measure design.

Results  The CDJ in Egyptian sections ranged from 0 to 2.0 mm (mean ± SD = 0.9 ± 0.4 mm) on the mesial side of the canal and from 0.2 to 2.5 mm (mean ± SD = 1.0 ± 0.5 mm) on the distal aspect. In the Saudi sample, the CDJ ranged from 0.5 to 1.2 mm (mean ± SD = 0.8 ± 0.3 mm) on the mesial side and from 0.6 to 0.9 mm (mean ± SD = 0.7 ± 0.4 mm) on the distal side. The mesial and distal differences between Egyptian and Saudi premolars on the mesial and distal surface were statistically significant (P < 0.001).

Conclusions  The location of the CDJ varied between the Egyptian and Saudi mandibular first premolars, indicating that this junction is not a fixed point in populations of different countries.
An evaluation of the usefulness of two endodontic case assessment forms by general dentists
Authors: Ree M. H. , Timmerman M. F. , Wesselink P. R.
Published: July 2003

Aim  To evaluate the use of two forms to assess the risks and difficulty of root‐canal treatment.

Methodology  Two criterion‐based forms, containing 15 and 16 items, respectively, were distributed to 83 general dentists to evaluate the potential difficulty of root‐canal treatment. The participants were asked to assess the difficulty of 15 endodontic cases using the Dutch Endodontic Treatment Index (DETI) and the Endodontic Treatment Classification (ETC) forms. A questionnaire was also provided to evaluate the time needed to complete the two forms, their ease of use, the clarity and/or appropriateness of the criteria and any other comments. The outcomes of the assessment were compared with the assessment of each case as carried out by the authors.

Results  The response rate was 53%. The DETI was an easy and rapid way to differentiate between uncomplicated and complicated cases. In 13 of the 15 cases, 88–100% of the dentists scored the cases in agreement with the authors. Use of the ETC form was more complicated, as a result of the larger number of variables. However, most respondents recognized the complicated cases, and 91% found the ETC form valuable to help in assessing the difficulty of endodontic cases.

Conclusions  These two forms may help general practitioners to assess the difficulty of endodontic problems and to decide whether to treat the case or to refer it to a specialist.
Ultrasound real‐time imaging in the differential diagnosis of periapical lesions
Authors: Cotti E. , Campisi G. , Ambu R. , Dettori C.
Published: July 2003

Aim  To assess whether the use of real‐time ultrasound imaging (echography), together with the application of ‘Colour Power Doppler’, can help the differential diagnosis of periapical lesions based on their contents.

Methodology  Eleven patients diagnosed with periapical lesions using conventional clinical and radiographic findings and who had been scheduled for endodontic surgery were examined using ultrasound imaging and Colour Power Doppler at the site of the lesions. Lesions were described in each case by an expert echographist, together with an endodontist, according to a scheme described previously. Information on the size of each lesion, its content and its vascular supply was gained and recorded by means of the ultrasound images; then, a tentative differential diagnosis between a cyst and a granuloma was made. The lesions obtained during endodontic surgery were processed and examined with a light microscope. The results from the biopsies were compared with the descriptions made with the ultrasound images.

Results  The differential diagnoses between periapical granulomas and cystic lesions, which were based on the echograpic findings, were confirmed by the results of the histopathologic examination in all the 11 cases: four being granulomas and seven being cystic lesions.

Conclusions  Ultrasound real‐time imaging is a technique that may help make a differential diagnosis between cysts and granulomas by revealing the nature of the content of a bony lesion. This technique may have further applications in the study of other lesions of the jaws.
Osteoblasts and MG‐63 osteosarcoma cells behave differently when in contact with ProRoot™ MTA and White MTA
Authors: Pérez A. L. , Spears R. , Gutmann J. L. , Opperman L. A.
Published: July 2003

Aim  To test the hypothesis that MG‐63 osteosarcoma cells and primary osteoblasts react differently to ProRoot™ MTA (mineral trioxide aggregate) and White MTA by: (i) investigating the attachment of primary osteoblasts and MG‐63 osteosarcoma cells to ProRoot™ MTA and White MTA; and (ii) comparing the osteogenic behaviour of both cell lines in contact with these endodontic materials.

Methodology  Primary osteoblasts were harvested from foetal rat calvaria by sequential digestion and MG‐63 osteosarcoma cells were purchased. Cells were exposed to ProRoot™ MTA and White MTA prepared according to the manufacturer's instructions. All samples and controls were prepared in quadruplicate. After 6, 9 and 13 days exposure to MTA, the cells were fixed and prepared for SEM examination. In addition, both the cell types were grown to confluence and exposed to β‐glycerophosphate and dexamethasone to assess mineralized nodule formation as a function of osteogenic behaviour.

Results  The number of cells on the surface of the culture dish and on top of the materials increased in all samples throughout the 3 time periods, except for White MTA where no primary osteoblasts were visible on top of the material by the end of 13 days. After exposing cells to differentiation medium nodules were observed in cultures of primary osteoblasts, but not of MG‐63 osteosarcoma cells.

Conclusions  Under the conditions of this study, whilst primary osteoblasts initially bound to White MTA, they did not survive on the surface by the end of 13 days. Primary osteoblasts formed mineralized nodules when exposed to differentiation medium, whilst MG‐63 cells did not form nodules. As MG‐63 cells do not behave osteogenically by forming mineralized nodules, and primary osteoblasts are more sensitive than MG‐63 osteosarcoma cells to White MTA in cell culture, primary osteoblasts are more appropriate than MG‐63 cells for testing endodontic materials in cell culture.
Research partnerships: collaborative action research in nursing
Authors: Titchen Angle , Binnie Alison
Published: July 2003

This methodological paper discusses and critiques the ‘insider’ and ‘outsider’ models of action research described in the nursing literature It highlights tensions and problems with these models and demonstrates how the models developed by the authors — the ‘double‐act’ and ‘collaborative group’ partnerships — overcome these difficulties The success of this approach suggests that such partnerships of nurse practitioners and a researcher should be considered when practitioners want to introduce innovation and facilitate change in practice and generate and test theory which is relevant to practice The paper is presented in the form of a commentary, interspersed with reflective conversations in which the authors illustrate and reflect upon their attempts to make the methodology described a reality
The significance of the relationship between a discipline and its practice
Authors: Grossman Mary , Hooton Margaret
Published: July 2003

In this paper, it is argued that the absence of conceptual consensus across the university and its sectors is largely responsible for the growing gap between the goals of the discipline and its practice Both discipline and practice are defined, their symbiotic relationship explored, and specific strategies proposed, to enhance the development of the profession In particular, the need for a shared conceptual framework which would transcend university and service structures to promote an academic practice is examined in addition to the benefits of instituting theoretically based daily rounds and Journal club in the practice setting
Methodological considerations in the study of frail elderly people
Authors: Bowsher Juanita , Bramlett Martha , Burnside Irene M , Gueldner Sarah H
Published: July 2003

The purpose of this paper is to increase the awareness of gerontological nurse researchers about methodological, theoretical and ethical issues that are unique and critical to the study of frail elderly people Discussion focuses on (a) sampling, recruitment, informed consent and retention of subjects, (b) selection and adaptation of measurement instruments, (c) implementation of treatment modalities and data collection protocols, (d) theoretical shortcomings, and (e) ethical concerns Such issues must be resolved if answers are to be found for multiple health problems that pose such a heavy burden for many frail elderly people As the number in this highly vulnerable group increases, gerontological nurse scientists, like all health care researchers, must better understand their needs and discover their strengths We must design innovative research protocols to capture that information
Issues in the supervision of postgraduate research students in nursing
Authors: Sheehan John
Published: July 2003

Some general points are made in this paper about the nature of postgraduate research degrees, and the process which results in a thesis is set out These are followed by considering the degrees in a nursing context and also in relation to the social sciences Next the aims of postgraduate research degree programmes are considered Approaches to the matching of students are set out Among those discussed are mentoring, collegiality, classification and framing, and the use of workshops In the conclusion, some desired outcomes of the supervisory process are suggested
Problem solving in nursing practice: application, process, skill acquisition and measurement
Authors: Roberts Julia D , While Alison E , Fitzpatrick Joanne M.
Published: July 2003

This paper analyses the role of problem solving in nursing practice including the process, acquisition and measurement of problem‐solving skills It is argued that while problem‐solving ability is acknowledged as critical if today's nurse practitioner is to maintain effective clinical practice, to date it retains a marginal place in nurse education curricula Further, it has attracted limited empirical study Such an omission, it is argued, requires urgent redress if the nursing profession is to meet effectively the challenges of the next decade and beyond
The art of nursing: the experience of patients and nurses*
Authors: Appleton Cathy
Published: July 2003

Historical and contemporary conceptualizations of nursing have not addressed the art of nursing from an experiential research approach This study explores patients’ and nurses’ experiences of the art of nursing using a phenomenological‐ hermeneutic approach to enquiry that allows for exploration of the empirical experience Explicating a paradigm of the art of nursing, five distinct metathemes express nursing as art and describe the complex artistic processes that are lived through the nurse and patient
Searching for health needs: the work of health visiting
Authors: Chalmers Karen I
Published: July 2003

Searching out health needs and stimulating clients’ awareness of health needs are two key principles of health visiting practice However, there is little empirically based knowledge of how health visitors carry out these functions in their daily work The purpose of this paper is to describe and analyse health visitors’ work in searching for health needs and promoting clients’ awareness and actions in response to professionally identified needs Forty‐five health visitors were interviewed by means of semi‐structured, conversational interviews Findings identified that searching for health needs occurred in four types of situations These were needs that were (a) client initiated, (b) easily seen, (c)‘opened up’ by the health visitor, and (d) suspected and hidden Several processes were involved in searching for needs and stimulating clients’ awareness and actions, including questioning, using illustrations from other client situations, normalizing, assigning homework, assessing and intervening while searching, and responding to cues Timing played an important part in when and how interventions to search out needs occurred This study contributes to our understanding of how health visitors work in the community to promote individual and family health