bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Lymphatic Mapping on the New Tumor-Node-Metastasis Classification for Colorectal Cancer
Authors: Bilchik Anton J. , Nora Dean T. , Sobin Leslie H. , Turner Roderick R. , Trocha Steven , Krasne David , Morton Donald L.
Published: February 2003

Purpose: Sensitive detection methods and accurate reporting are necessary to determine the prognostic significance of micrometastases (MM) and isolated tumor cells (ITCs) in lymph nodes that drain colorectal cancers (CRCs). This study examined the role of lymphatic mapping (LM) in the application of the new tumor-node-metastasis (TNM) classification for MM and ITC.

Patients and Methods: All patients at the John Wayne Cancer Institute underwent LM immediately before standard resection of primary CRC between 1996 and 2001. Sentinel nodes (SNs) were identified using blue dye and/or radiotracer and were examined by hematoxylin-eosin (H&E) staining, cytokeratin immunohistochemistry, and multilevel sectioning. The comparison group comprised 370 patients whose primary CRCs were resected without LM during the same period at the same institution.

Results: LM was successfully performed in 115 of 120 (96%) patients and correctly predicted the tumor status of the nodal basin in 110 of 115 (96%) patients. Thirty-seven patients (32%) were lymph node-positive by H&E; ITC and MM were found in 23 patients (29.4%) whose lymph nodes were negative by H&E. Tumor deposits were found in the SN only in 29 patients (50%). Nodal involvement was identified for 14.3%, 30%, 74.6%, and 83.3% of T1, T2, T3, and T4 tumors, respectively, in the study group, and for 6.8%, 8.5%, 49.3%, and 41.8% of T1, T2, T3, and T4 tumors, respectively, in the comparison group. The study group had a higher percentage of nodal metastases (53% v 36%; P < .01) and a higher incidence of MM and ITC (29.4% v 1.9%; P < .0001). The mean number of lymph nodes found in the study group (14) was also significantly more than the number found in the comparison group (10; P < .00001).

Conclusion: Conventional examination of lymph nodes for CRC is inadequate for the detection of MM and ITC as described in the new TNM classification. Thus, LM and focused SN analysis should be considered to fully stage CRC.
Pregnancy Outcome of Partners of Male Survivors of Childhood Cancer: A Report From the Childhood Cancer Survivor Study
Authors: Green Daniel M. , Whitton John A. , Stovall Marilyn , Mertens Ann C. , Donaldson Sarah S. , Ruymann Frederick B. , Pendergrass Thomas W. , Robison Leslie L.
Published: February 2003

Purpose: This study was undertaken to determine the effect, if any, on pregnancy loss, live births, and birthweight of treatment for cancer diagnosed during childhood or adolescence.

Patients and Methods: We reviewed pregnancy outcome among sexually active male Childhood Cancer Survivor Study (CCSS) participants who responded to a questionnaire before February 3, 2000. Medical records of all members of the cohort were abstracted to obtain chemotherapeutic agents administered, the cumulative dose of drug administered for several drugs of interest, and the doses, volumes, and dates of administration of all radiotherapy.

Results: There were 4,106 sexually active males; 1,227 reported they sired 2,323 pregnancies (69% live births, 1% stillbirths, 13% miscarriages, 13% abortions, 5% unknown or in gestation). The male-to-female ratio of the offspring of the partners of the male survivors was significantly different from that of the offspring of the partners of the male siblings of the survivors (1.0:1.03 v 1.24:1.0) (P = .016). The proportion of pregnancies of the partners of male survivors that ended with a liveborn infant was significantly lower than for the partners of the male siblings of the survivors who were the control group for comparison (relative risk = 0.77, P = .007). There were no significant differences in pregnancy outcome by treatment.

Conclusion: This large study did not identify adverse pregnancy outcomes for the partners of male survivors treated with most chemotherapeutic agents. The reversal of the sex ratio and the association observed for procarbazine warrant further investigation.
Health-Related Quality-of-Life Parameters as Independent Prognostic Factors in Advanced or Metastatic Bladder Cancer
Authors: Roychowdhury D.F. , Hayden A. , Liepa A.M.
Published: February 2003

Purpose: This retrospective analysis examined prognostic significance of health-related quality-of-life (HRQoL) parameters combined with baseline clinical factors on outcomes (overall survival, time to progressive disease, and time to treatment failure) in bladder cancer.

Patients and Methods: Outcome and HRQoL (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30) data were collected prospectively in a phase III study assessing gemcitabine and cisplatin versus methotrexate, vinblastine, doxorubicin, and cisplatin in locally advanced or metastatic bladder cancer. Prespecified baseline clinical factors (performance status, tumor-node-metastasis staging, visceral metastases [VM], alkaline phosphatase [AP] level, number of metastatic sites, prior radiotherapy, disease measurability, sex, time from diagnosis, and sites of disease) and selected HRQoL parameters (global QoL; all functional scales; symptoms: pain, fatigue, insomnia, dyspnea, anorexia) were evaluated using Cox’s proportional hazards model. Factors with individual prognostic value (P < .05) on outcomes in univariate models were assessed for joint prognostic value in a multivariate model. A final model was developed using a backward selection strategy.

Results: Patients with baseline HRQoL were included (364 of 405, 90%). The final model predicted longer survival with low/normal AP levels, no VM, high physical functioning, low role functioning, and no anorexia. Positive prognostic factors for time to progressive disease were good performance status, low/normal AP levels, no VM, and minimal fatigue; for time to treatment failure, they were low/normal AP levels, minimal fatigue, and no anorexia. Global QoL was a significant predictor of outcome in univariate analyses but was not retained in the multivariate model.

Conclusion: HRQoL parameters are independent prognostic factors for outcome in advanced bladder cancer; their prognostic importance needs further evaluation.
Hereditary Breast-Ovarian Cancer at the Bedside: Role of the Medical Oncologist
Authors: Lynch Henry T. , Snyder Carrie L. , Lynch Jane F. , Riley Bronson D. , Rubinstein Wendy S.
Published: February 2003

Purpose: To provide practical considerations for diagnosing, counseling, and managing patients at high risk for hereditary breast cancer. Design: We have studied 98 extended hereditary breast cancer (HBC)/hereditary breast-ovarian cancer (HBOC) families with BRCA1/2 germline mutations. From these families, 1,315 individuals were counseled and sampled for DNA testing. Herein, 716 of these individuals received their DNA test results in concert with genetic counseling. Several challenging pedigrees were selected from Creighton University’s hereditary cancer family registry, as well as one family from Evanston/Northwestern Healthcare, to be discussed in this present report.

Results: Many obstacles were identified in diagnosis, counseling, and managing patients at high risk for HBC/HBOC. These obstacles were early noncancer death of key relatives, perception of insurance or employment discrimination, fear, anxiety, apprehension, reduced gene penetrance, and poor compliance. Other important issues such as physician culpability and malpractice implications for failure to collect or act on the cancer family history were identified.

Conclusion: When clinical gene testing emerged for BRCA1 and BRCA2, little was known about the efficacy of medical interventions. Potential barriers to uptake of testing were largely unexplored. Identification and referral of high-risk patients and families to genetic counseling can greatly enhance the care of the population at the highest risk for cancer. However, because premonitory physical stigmata are absent in most of these syndromes, an HBOC diagnosis may be missed unless a careful family history of cancer of the breast, ovary, or several integrally associated cancers is obtained.
Barriers to Hospice Care Among Older Patients Dying With Lung and Colorectal Cancer
Authors: McCarthy Ellen P. , Burns Risa B. , Davis Roger B. , Phillips Russell S.
Published: February 2003

Purpose: To identify factors associated with hospice enrollment and length of stay in hospice among patients dying with lung or colorectal cancer. Methods: We used the Linked Medicare-Tumor Registry Database to conduct a retrospective analysis of the last year of life among Medicare beneficiaries diagnosed with lung or colorectal cancer at age ≥ 66 years between January 1, 1973, and December 31, 1996, in the Surveillance, Epidemiology, and End Results Program who died between January 1, 1988, and December 31, 1998. Our outcomes of interest were time from cancer diagnosis to hospice enrollment and length of stay in hospice care. We used Cox proportional hazards regression to adjust for demographic and clinical information.

Results: We studied elderly patients dying with lung cancer (n = 62,117) or colorectal cancer (n = 57,260). Overall, 27% of patients (n = 16,750) with lung cancer and 20% of patients (n = 11,332) with colorectal cancer received hospice care before death. Median length of stay for hospice patients with lung and colorectal cancer was 25 and 28 days, respectively. Overall, 20% of patients entered hospice within 1 week of death, whereas 6% entered more than 6 months before death. Factors associated with later hospice enrollment include being male; being of nonwhite, nonblack race; having fee-for-service insurance; and residing in a rural community. Many of these factors also were associated with shorter stays in hospice.

Conclusion: Although use of hospice care has increased dramatically over time, specific patient groups, including men, patients residing in rural communities, and patients with fee-for-service insurance continue to experience delays in hospice enrollment.
Phase III Study of Concurrent Chemoradiotherapy Versus Radiotherapy Alone for Advanced Nasopharyngeal Carcinoma: Positive Effect on Overall and Progression-Free Survival
Authors: Lin Jin-Ching , Jan Jian-Sheng , Hsu Chen-Yi , Liang Wen-Miin , Jiang Rong-San , Wang Wen-Yi
Published: February 2003

Purpose: Nasopharyngeal carcinoma (NPC) is a radiosensitive and chemosensitive tumor. This randomized phase III trial compared concurrent chemoradiotherapy (CCRT) versus radiotherapy (RT) alone in patients with advanced NPC.

Patients and Methods: From December 1993 to April 1999, 284 patients with 1992 American Joint Committee on Cancer stage III to IV (M0) NPC were randomly allocated into two arms. Similar dosage and fractionation of RT was administered in both arms. The investigational arm received two cycles of concurrent chemotherapy with cisplatin 20 mg/m2/d plus fluorouracil 400 mg/m2/d by 96-hour continuous infusion during the weeks 1 and 5 of RT. Survival analysis was estimated by the Kaplan-Meier method and compared by the log-rank test.

Results: Baseline patient characteristics were comparable in both arms. After a median follow-up of 65 months, 26.2% (37 of 141) and 46.2% (66 of 143) of patients developed tumor relapse in the CCRT and RT-alone groups, respectively. The 5-year overall survival rates were 72.3% for the CCRT arm and 54.2% for the RT-only arm (P = .0022). The 5-year progression-free survival rates were 71.6% for the CCRT group compared with 53.0% for the RT-only group (P = .0012). Although significantly more toxicity was noted in the CCRT arm, including leukopenia and emesis, compliance with the combined treatment was good. The second cycle of concurrent chemotherapy was refused by nine patients and was delayed for ≥ 1 week for another nine patients. There were no treatment-related deaths in either arm.

Conclusion: We conclude that CCRT is superior to RT alone for patients with advanced NPC in endemic areas.
Programming of Rat Muscle and Fat Metabolism by in Utero Overexposure to Glucocorticoids
Authors: Cleasby Mark E. , Kelly Paul A. T. , Walker Brian R. , Seckl Jonathan R.
Published: February 2003

In utero overexposure to glucocorticoids may explain the association between low birth weight and subsequent development of the metabolic syndrome. We previously showed that prenatal dexamethasone (dex) exposure in the rat lowers birth weight and programs adult fasting and postprandial hyperglycemia, associated with increased hepatic gluconeogenesis driven by elevated liver glucocorticoid receptor (GR) expression. This study aimed to determine whether prenatal dex (100 μg/kg per day from embryonic d 15 to embryonic d 21) programs adult GR expression in skeletal muscle and/or adipose tissue and whether this contributes to altered peripheral glucose uptake or metabolism. In utero dex-exposed rats remained lighter until 6 months of age, despite some early catch-up growth. Adults had smaller epididymal fat pads, with a relative increase in muscle size. Although glycogen storage was reduced in quadriceps, 2-deoxyglucose uptake into extensor digitorum longus muscle was increased by 32% (P < 0.05), whereas uptake in other muscles and adipose beds was unaffected by prenatal dex. GR mRNA was not different in most muscles but selectively reduced in soleus (by 23%, P < 0.05). However, GR mRNA was markedly increased specifically in retroperitoneal fat (by 50%, P < 0.02). This was accompanied by a shift from peroxisomal proliferator-activated receptor γ1 to γ2 expression and a reduction in lipoprotein lipase mRNA (by 28%, P < 0.02). Adipose leptin, uncoupling protein-3 and resistin mRNAs, muscle GLUT-4, and circulating lipids were not affected by prenatal dex. These data suggest that hyperglycemia in 6-month-old rats exposed to dexamethasone in utero is not due to attenuated peripheral glucose disposal. However, increased GR and attenuated fatty acid uptake specifically in visceral adipose are consistent with insulin resistance in this crucial metabolic depot and could indirectly contribute to increased hepatic glucose output.
Dose-Response Effects of 2-Methoxyestradiol on Estrogen Target Tissues in the Ovariectomized Rat
Authors: Sibonga J. D. , Lotinun S. , Evans G. L. , Pribluda V. S. , Green S. J. , Turner R. T.
Published: February 2003

In three experiments, we evaluated the pharmacological effects of 2-methoxyestradiol (2ME2) on several estrogen target tissues. Experiment 1: we gavaged recently ovariectomized (OVX) 9.5-wk-old rats with 2ME2 at doses of 0, 0.1, 1, 4, 20, and 75 mg/kg in a 21-d dose-response study. 2ME2 reduced body weight and serum cholesterol, increased uterine weight and epithelial cell height, and inhibited longitudinal and radial bone growth compared with values in the untreated OVX rat. All doses of 2ME2 maintained cancellous bone mass at the baseline level, the lowest effective dose being 20-fold less than a uterotrophic dose. Experiment 2: in an 8-wk experiment in adult OVX rats, a nonuterotrophic dose of 2ME2 (4 mg/kg·d) suppressed body weight gain, inhibited bone formation in cancellous bone and partially prevented bone loss in the tibial metaphysis. Experiment 3: in weanling rats, ICI 182,780 did not antagonize the effect of 2ME2. We conclude that 2ME2 antagonizes the skeletal changes that follow OVX at doses that have minimal or no effects in the uterus in both young and adult rats; 2ME2 does not appear to act via estrogen receptors and is active on bone at doses well below those required for tumor suppression in mice. 2ME2, through a novel pathway, may be a useful alternative to conventional hormone replacement therapy for prevention of postmenopausal bone loss.
Expression of Aryl Hydrocarbon Receptor and Aryl Hydrocarbon Receptor Nuclear Translocator Messenger Ribonucleic Acids and Proteins in Rat and Human Testis
Authors: Schultz Rüdiger , Suominen Janne , Värre Tanja , Hakovirta Harri , Parvinen Martti , Toppari Jorma , Pelto-Huikko Markku
Published: February 2003

Dioxins, e.g. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), use the aryl hydrocarbon receptor (AHR)/aryl hydrocarbon receptor nuclear translocator (ARNT) receptor complex to mediate their toxic actions. In addition to interaction with environmental pollutants, several transcription factors, steroid receptors, and growth factors are capable interacting with the AHR/ARNT complex, which suggests a constitutive role for the receptor complex.

The testis has been reported to be among the most sensitive organs to TCDD exposure. Our experiments revealed a complex distribution of AHR and ARNT mRNAs and proteins in rat and human testis. AHR and ARNT immunoreactivities could be detected in the nuclei of interstitial and tubular cells. The incubation of seminiferous tubules in a serum-free culture medium resulted in up-regulation of AHR mRNA, which could be depressed by adding FSH to the culture medium. Furthermore, the incubation of tubular segments with a solution of 1 or 100 nm TCDD resulted in a 2- to 3-fold increase in apoptotic cells. Thus, up-regulation of AHR in cultured tubular segments and consecutive depression by FSH suggest a role for AHR in controlled cell death during spermatogenesis. We suggest that AHR and ARNT mediate effects by direct action on testicular cells in the rat and human testis.
Gene Expression Is Differentially Regulated in the Epididymis after Orchidectomy
Authors: Ezer Nadine , Robaire Bernard
Published: February 2003

The epididymis is the site for the transport, maturation, and storage of spermatozoa. Regulation of epididymal structure and function is highly dependent on the ipsilateral testis. At the molecular level, however, few studies have been undertaken to determine which genes are expressed in the epididymis under testicular regulation. The goal of this study was to identify genes for which expression is regulated after orchidectomy, both throughout the epididymis and in a segment-specific manner. Microarrays spotted with 474 rat cDNAs were used to examine gene expression changes over the first 7 d post orchidectomy in the initial segment, caput, corpus, and cauda epididymidis of the adult Brown Norway rat. Using k-means cluster analysis, we show that four patterns of gene expression are activated in each epididymal segment over the first week following orchidectomy. Transient up-regulation of gene expression in the epididymis after orchidectomy is described for the first time. Potential androgen-repressed genes, including Gpx-1, show increased expression in the epididymis after orchidectomy. Several glutathione-S-transferases and calcium-binding proteins decline throughout the epididymis after orchidectomy, indicating that these may be novel androgen-regulated epididymal genes. Other genes coding for metabolism-associated proteins, transporters, and α-1 acid glycoprotein show segment-specific regulation in the epididymis after orchidectomy. Finally, we describe the expression of the previously uncharacterized heat shock proteins, and apoptosis-associated genes in the epididymis after orchidectomy. Thus, gene expression in the epididymis is differentially affected over time after orchidectomy. These results provide novel insight into androgen-dependent and segment-specific epididymal function.
Follicle-Stimulating Hormone and Insulin-Like Growth Factor I Synergistically Induce Up-Regulation of Cartilage Link Protein (Crtl1) via Activation of Phosphatidylinositol-Dependent Kinase/Akt in Rat Granulosa Cells
Authors: Sun Guang Wei , Kobayashi Hiroshi , Suzuki Mika , Kanayama Naohiro , Terao Toshihiko
Published: February 2003

FSH and IGF-I are both important determinants of follicle development and the process of cumulus cell-oocyte complex expansion. FSH stimulates the phosphorylation of Akt by mechanisms involving phosphatidylinositol 3-kinase (PI3-K), a pattern of response mimicking that of IGF-I. Cartilage link protein (Crtl1) is confined to the cartilaginous lineage and is assembled into a macroaggregate complex essential for hyaluronan-rich matrix stabilization. The present studies were performed to determine the actions of FSH and IGF-I on Crtl1 production in rat granulosa cells. Primary cultures of granulosa cells were prepared from 24-d-old rats. After treatments, cell extracts and media were prepared, and the Crtl1 level was determined by immunoblotting analysis using anti-Crtl1 antibodies. Here we showed that 1) treatment with FSH (≥25 ng/ml) or IGF-I (≥25 ng/ml) for 4 h increased Crtl1 production; 2) maximal stimulatory effects of FSH or IGF-I were observed at 100 or 50 ng/ml, respectively; 3) FSH caused a concentration-dependent increase in IGF-I-induced Crtl1 production and vice versa; 4) FSH and IGF-I also up-regulate the expression of Crtl1 mRNA; 5) FSH- and IGF-I-dependent Crtl1 production were abrogated by PI3-K inhibitors (LY294002 and wortmannin), and inhibition of Crtl1 production by p38 mitogen-activated protein kinase inhibitor (SB202190) was partial (∼30%), suggesting that PI3-K and, to a lesser extent, p38 mitogen-activated protein kinase are critical for the response. Our study represents the first report that FSH amplifies IGF-I-mediated Crtl1 production, possibly via PI3-K-Akt signaling cascades in rat granulosa cells.
Early Inflammatory Responses in Experimental Cardiac Hypertrophy and Fibrosis: Effects of 11β-Hydroxysteroid Dehydrogenase Inactivation
Authors: Young Morag J. , Moussa Leon , Dilley Rod , Funder John W.
Published: February 2003

In epithelial tissues such as kidney, mineralocorticoid receptors (MR) are protected against glucocorticoid occupancy by the enzyme 11β-hydroxysteroid dehydrogenase (11βHSD) type 2. If the enzyme is congenitally inactive, or blocked by carbenoxolone, physiologic glucocorticoids act as MR agonists in such tissues. In most nonepithelial tissues, including cardiomyocytes, 11βHSD2 is expressed at minimal levels; in these tissues physiologic glucocorticoids act as MR antagonists, with the basis for this tissue selectivity currently unknown. Vascular smooth muscle cells (VSMC) express MR and 11βHSD1/2, with 11βHSD1 reported to show uncharacteristic oxidase activity, so that VSMC thus constitute a potential physiologic aldosterone target tissue. Because mineralocorticoid/salt administration triggers marked inflammatory responses in coronary vasculature, we reasoned that VSMC (like epithelial) MR may be activated by glucocorticoids if the protective enzyme is blocked. We thus gave uninephrectomized rats 0.9% NaCl solution to drink, and deoxycorticosterone (DOC, as a single 20 mg sc dose) or carbenoxolone (CBX, 2.5 mg/d in the drinking solution). Both DOC and CBX increased systolic blood pressure, heart, and kidney weight, and expression of cyclooxygenase 2, ED-1-positive macrophages, and osteopontin, with effects of both DOC and CBX blocked by the selective MR antagonist eplerenone. These findings suggest that local glucocorticoid excess, reflecting lower VSMC 11βHSD1/2 activity may mimic systemic mineralocorticoid excess, and play a direct etiologic role in coronary vascular inflammatory responses under circumstances of a high salt intake.
Live-cell monitoring of tyrosine phosphorylation in focal adhesions following microtubule disruption
Authors: Kirchner Jochen , Kam Zvi , Tzur Gila , Bershadsky Alexander D. , Geiger Benjamin
Published: February 2003

Tyrosine phosphorylation of focal adhesion components is involved in the regulation of focal adhesion formation and turnover, yet the underlying molecular mechanisms are still poorly defined. In the present study, we have used quantitative fluorescence microscopy to investigate the dynamic relationships between the incorporation of new components into growing focal adhesions and tyrosine phosphorylation of these sites. For this purpose, a new approach for monitoring phosphotyrosine levels in live cells was developed,based on a `phosphotyrosine reporter' consisting of yellow fluorescent protein fused to two consecutive phosphotyrosine-binding Src-homology 2 (SH2)-domains derived from pp60c-Src. This YFP-dSH2 localized to cell-matrix adhesions and its intensity was linearly correlated with that of an anti-phosphotyrosine antibody labeling. The differential increase in vinculin and phosphotyrosine levels was examined in live cells by two-color time-lapse movies of CFP-vinculin and YFP-dSH2. In this study, focal adhesion growth was triggered by microtubule disruption, which was previously shown to stimulate focal adhesion development by inducing cellular contraction. We show here that, 2 minutes after addition of the microtubule-disrupting drug nocodazole,the local densities of the focal adhesion-associated proteins vinculin,paxillin and focal adhesion kinase (FAK) are significantly elevated and the focal adhesion area is increased, whereas elevation in tyrosine phosphorylation inside the growing adhesions occurs only a few minutes later. Phosphotyrosine and FAK density reach their maximum levels after 10 minutes of treatment, whereas vinculin and paxillin levels as well as focal adhesion size continue to grow, reaching a plateau at about 30 minutes. Our findings suggest that protein recruitment and growth of focal adhesions are an immediate and direct result of increased contractility induced by microtubule disruption,whereas tyrosine phosphorylation is activated later.
γ-Secretase activity requires the presenilin-dependent trafficking of nicastrin through the Golgi apparatus but not its complex glycosylation
Authors: Herreman An , Van Gassen Geert , Bentahir Mustapha , Nyabi Omar , Craessaerts Katleen , Mueller Ulrike , Annaert Wim , De Strooper Bart
Published: February 2003

Nicastrin and presenilin are two major components of the γ-secretase complex, which executes the intramembrane proteolysis of type I integral membrane proteins such as the amyloid precursor protein (APP) and Notch. Nicastrin is synthesized in fibroblasts and neurons as an endoglycosidase-H-sensitive glycosylated precursor protein (immature nicastrin) and is then modified by complex glycosylation in the Golgi apparatus and by sialylation in the trans-Golgi network (mature nicastrin). These modifications are not observed with exogenously overexpressed nicastrin. Under normal cell culture conditions, only mature nicastrin is expressed at the cell surface and binds to the presenilin heterodimers. Mature nicastrin has a half-life of more than 24 hours. In the absence of presenilin 1 and 2,nicastrin remains entirely endoglycosidase H sensitive, is retained in the endoplasmic reticulum and is slowly degraded. Single presenilin 1 or presenilin 2 deficiency affects glycosylation of nicastrin to a lesser extent than the combined presenilin deficiencies, suggesting a correlation between either the transport of nicastrin out of the endoplasmic reticulum or the concomitant complex glycosylation of nicastrin, and γ-secretase activity. However, when complex glycosylation of nicastrin was inhibited using mannosidase I inhibitors, γ-secretase cleavage of APP or Notch was not inhibited and the immature nicastrin still associates with presenilin and appears at the cell surface. Complex glycosylation of nicastrin is therefore not needed for γ-secretase activity. Because the trafficking of nicastrin to the Golgi apparatus is dependent on presenilins, our data point to a central role of presenilin in nicastrin maturation/localization, which could help to partially resolve the `spatial paradox'.
A β-catenin survival signal is required for normal lobular development in the mammary gland
Authors: Tepera Stacey B. , McCrea Pierre D. , Rosen Jeffrey M.
Published: February 2003

The Wnt (wingless) family of secreted glycoproteins initiates a signalling pathway implicated in the regulation of both normal mouse mammary gland development and tumorigenesis. Multiple Wnt signals ultimately converge on the multifunctional protein β-catenin to activate the transcription of target genes. Although β-catenin plays a crucial role in canonical Wnt signalling, it also functions in epithelial cell-cell adhesion at the adherens junctions. This study was designed to isolate β-catenin's signalling function from its role in adherence during mouse mammary gland development. A transgenic dominant-negative β-catenin chimera (β-eng), which retains normal protein-binding properties of wild-type β-catenin but lacks its C-terminal signalling domain, was expressed preferentially in the mammary gland. Thus, β-eng inhibits the signalling capacity of endogenousβ-catenin, while preserving normal cell-cell adhesion properties. Analysis of the mammary gland in transgenic mice revealed a severe inhibition of lobuloalveolar development and a failure of the mice to nurse their young. Expression of β-eng resulted in an induction of apoptosis both in transgenic mice and in retrovirally transduced HC11 cells. Thus, endogenousβ-catenin expression appears to be required to provide a survival signal in mammary epithelial cells, which can be suppressed by transgenic expression of β-eng. Comparison of the timing of transgene expression with the transgenic phenotype suggested a model in which β-catenin's survival signal is required in lobular progenitors that later differentiate into lobuloalveolar clusters. This study illustrates the importance ofβ-catenin signalling in mammary lobuloalveolar development.
A proximal femoral implant preserves physiological bone deformation: A biomechanical investigation in cadaveric bones
Authors: Macdonald W , Carlsson L V , Jacobsson C M , Lee T Q
Published: February 2003

The aim of this study was to compare the perturbances in bone deformation patterns of the proximal femur due to a conventional cemented femoral stem and a novel uncemented implant designed on the principles of osseointegration. Five matched pairs of fresh frozen human femora were mechanically tested. Bone deformation patterns, measured with a video digitizing system under 1.5 kN joint force, showed that the cemented Spectron femoral implant caused significant alterations to the proximal femoral deformation pattern, whereas the Gothenburg osseointegrated titanium femoral implant did not significantly alter the bone behaviour (p < 0.05). Vertical micromotions measured under 1 kN after 1000 cycles were within the threshold of movement tolerable for bone ingrowth (21 μm for the Gothenburg system and 26 μm for the cemented implant).
Investigations on the wear behaviour of the temporary PMMA-based hip Spacer-G®
Authors: Affatato S , Mattarozzi A , Taddei P , Robotti P , Soffiatti R , Sudanese A , Toni A
Published: February 2003

Total hip replacement has become one of the most successful orthopaedic procedures. However, complications due to infections may give serious problems and have devastating consequences for the hip implant. The use of a temporary three-dimensional polymethylmethacrylate (PMMA) cement spacer may be an alternative to solve infections in hip implants, improving the lives of patients awaiting reimplantation. In order to evaluate their wear behaviour, five PMMA Spacer-G® femoral heads were tested against five post-mortem pelves in a hip joint simulator with bovine calf serum as lubricant. The surface of the worn spacers was characterized by scanning electron microscopy (SEM) analysis; all the samples revealed a similar morphology, showing areas characterized by different degrees of wear. Particle debris was isolated from the lubricant and PMMA particles and bone fractions were quantified. The amount of debris was found to be higher than where no-temporary prostheses were used. However, this result is acceptable since wear debris is removed by lavage irrigation when the Spacer-G® is explanted. On the basis of these data, it is considered that the use of the cement Spacer-G® could be a promising approach to the treatment of complicated infections of the hip joint. Therefore, Spacer-G® is worthy of further research.
Fatigue strength of PMMA bone cement mixed with gentamicin and barium sulphate vs pure PMMA
Authors: Baleani M , Cristofolini L , Minari C , Toni A
Published: February 2003

Barium sulphate is added to polymethylmethacrylate (PMMA) bone cement as a radio-pacifier. Gentamicin is an antibiotic added to bone cement to treat or prevent infection in arthroplasty. This study investigated the combined effect of barium sulphate and gentamicin sulphate on the fatigue strength of PMMA bone cement. Three different formulations were studied: pure PMMA, PMMA with barium sulphate added and PMMA with barium sulphate and gentamicin sulphate added. Before testing all specimens were stored in water at 37°C for at least 15 days to season the PMMA and to elute the antibiotic. Fatigue tests were performed following a previously validated procedure. The slope part of the Wöhler diagram was obtained and a rough endurance limit was estimated for all three formulations.

The experimental data showed that the addition of barium sulphate to PMMA bone cement affected the fatigue strength of the material, whereas addition of gentamicin sulphate to the radiopaque PMMA had no effect on the fatigue properties of the bone cement. While PMMA with barium sulphate added was confirmed to have a reduced fatigue strength when compared with plain PMMA, no detrimental effect was found for the addition of gentamicin sulphate to radiopaque PMMA.
In vitro strain-induced endothelial cell dysfunction determined by DNA synthesis
Authors: Woodell J E , LaBerge M , Langan E M , Hilderman R H
Published: February 2003

Rapid re-endothelialization following balloon angioplasty can reduce restenosis by inhibiting smooth muscle cell migration and proliferation. However, formation of a neointima following angioplasty can be inhibited due to endothelial cell dysfunction and denudation. The purpose of this study was to evaluate mechanical tensile stress as a cause of endothelial cell dysfunction. The Flexercell® strain unit was utilized to generate both short-term cyclic and static tensile strain on cultured bovine aortic endothelial cells (BAECs). Before analysis of this loading on BAECs, strain behaviour of the Flexercell® system and DNA assay conditions were optimized. This paper demonstrates that, when compared with unloaded controls, 4-h cyclic loading at 4 per cent elongation and 0.1 Hz, and static loading at 4 per cent elongation cause a 44 and 70 per cent decrease in DNA synthesis respectively. In a companion paper, it is demonstrated that low DNA synthesis levels in mechanically loaded cells can be increased by incubation with Ap4A and/or NO donors.
P1, P4-diadenosine 5′-tetraphosphate induced DNA synthesis in mechanically injured cultured endothelial cells
Authors: Woodell J E , LaBerge M , Langan E M , Hilderman R H
Published: February 2003

Rapid re-endothelialization following balloon angioplasty can reduce restenosis by inhibiting smooth muscle cell migration and proliferation. However, formation of a neointima layer following angioplasty can be inhibited due to endothelial cell dysfunction and denudation. In a companion paper, it has been illustrated that mechanical loading causes a decrease in DNA synthesis in bovine aortic endothelial cells (BAECs) thus rendering them dysfunctional. The purpose of this study was to overcome BAEC dysfunction by incubation with pharmacological agents to increase DNA synthesis. Previous studies demonstrated that the adenosine dinucleotides Ap4A and Ap2A induced nitric oxide (NO) production from BAEC while Ap3A, Ap5A and Ap6A did not. This paper demonstrates that Ap4 and Ap2 A induce a 1.46- and 1.16-fold increase in DNA synthesis in mechanically stressed BAECs respectively, while Ap3A, Ap5A and Ap6A do not. Additionally, NOC-18, a slow NO release NO donor, significantly increases DNA synthesis in mechanically stressed BAECs without affecting unloaded cells. These results are consistent with NO inducing DNA synthesis in mechanically stressed BAECs.
Higher α-Olefin Polymerization Behavior of a Bis(Phenoxy-Imine)Titanium Complex/i-Bu3Al/Ph3CB(C6F5)4 Catalyst System
Authors: Saito Junji , Suzuki Yasuhiko , Fujita Terunori
Published: February 2003

Catalytic behavior of a bis(phenoxy-imine)Ti complex/i-Bu3Al/Ph3CB(C6F5)4 catalyst system for higher α-olefin polymerization was investigated. The catalyst system exhibited higher activities towards α-olefins having larger molecular sizes and formed ultra-high molecular weight poly(higher α-olefin)s.
Doubly N-Confused Porphyrins as Efficient Sensitizers for Singlet Oxygen Generation
Authors: Araki Koiti , Engelmann Fábio M , Mayer Idemar , Toma Henrique E , Baptista Maurício S , Maeda Hiromitsu , Osuka Atsuhiro , Furuta Hiroyuki
Published: February 2003

The high singlet oxygen quantum yield (ca. 0.8) for the Ag(III) complex of doubly N-confused porphyrin, a potential PDT photosensitizer, was observed according to its favourable intersystem crossing and the triplet lifetime characteristics.
Selective One-pot Synthesis of Facial Tris-ortho-metalated Iridium(III) Complexes Using Microwave Irradiation
Authors: Konno Hideo , Sasaki Yoshiyuki
Published: February 2003

We report on a novel synthesis method for the production of two facial tris-ortho-metalated iridium(III) complexes, fac-[Ir(ppy)3] (1a; ppyH = 2-phenylpyridine) and fac-[Ir(tpy)3] (1b; tpyH = 2-(p-tolyl)pyridine), by the reaction of IrCl3·3H2O with a large excess of the corresponding 2-arylpyridine under microwave irradiation. The method does not require a dehalogenating reagent such as AgCF3SO3, and facial tris-ortho-metalated iridium(III) complexes can be obtained rapidly, selectively and efficiently.
The Himalayan rabbit (Oryctolagus cuniculus L.): spontaneous incidences of endpoints from prenatal developmental toxicity studies
Authors: Viertel B. , Trieb G.
Published: February 2003

The historical database represents the spontaneous, i.e. normal changes of characters, in laboratory animals, and is a must for the assessment of toxic effects of compounds. For the Himalayan rabbit (CHBB:HM, SPF) background data were collected from the control groups of regulatory studies between 1968-1999 in the Biberach laboratory of Boehringer Ingelheim (Germany). In the present study these data were compared with the background data from the years 1974-1984, with those from the Ingelheim laboratory, Germany (1977-1984) and those from the breeding colony at Kawanishi, Japan (1971-1991, 1972-1984).

Fertility in the Biberach laboratory was relatively constant through the years, due to the strict breeding system. Litter parameters (corpora lutea, implantations and viable fetuses), including fetal sex distribution and fetal weight, were constant in the Biberach laboratory through the years and compared well with the data from Ingelheim and Kawanishi.

From these three laboratories the results of spontaneous changes in fetal morphology above 0.1% incidence suggest a pattern of deviations from the Bauplan (fundamental body plan). These comprise synosteosis of sternebrae, lumbar (additional) ribs, hypoplasia of 12th rib, status of ossification, aplasia of gall bladder, hypoplasia of gall bladder, incompletely subdivided lung, dilated ventricle of heart, deviations at the A. carotis and at the aortic arch and flexure of paw. The absence of a time-dependent statistical trend indicates that the spontaneous change of endpoints remained constant through the time axis.

Comparison with the spontaneously changed fetal morphology of the other strains (NZW, JW, SF rabbits) does not provide support for their being a totally strain-specific pattern, and this pattern may be closer to the species than specific to a single strain. The firm patterns of deviations in fetal morphology provide suitable and valuable markers for assessing toxic effects on ontogenesis. According to our experience these morphological endpoints react very sensitively to teratogenic compounds, which is demonstrated by increased incidences. Our knowledge of evolution of organisms and of mechanisms leading to morphological deviations points to a strict selection of phenotypes. For laboratory animals the decisive selection factors are defined by man. These are nutritive factors, environmental conditions, the mating system, handling and treatment, and experimental design. All these factors have to be held constant through the years, which is an absolute pre-condition for the application of valid historical data.

The Himalayan rabbit is highly suitable for use in developmental toxicity studies due to the stability of reproductive data within the same laboratory over a period of more than 30 years, due to the similarity of reproductive data among three different laboratories, and due to an absence of relevant differences to the reproductive data of other rabbit strains.
The effects of different rack systems on the breeding performance of DBA/2 mice
Authors: Tsai P.-P. , Oppermann D. , Stelzer H. D. , Mähler M. , Hackbarth H.
Published: February 2003

Housing systems for laboratory animals have been developed over a long time. Micro-environmental systems such as positive, individually ventilated caging systems and forced-air-ventilated systems are increasingly used by many researchers to reduce cross contamination between cages. There have been many investigations of the impact of these systems on the health of animals, the light intensity, the relative humidity and temperature of cages, the concentration of ammonia and CO2, and other factors in the cages. The aim of the present study was to compare the effects of different rack systems and to understand the influence of environmental enrichment on the breeding performance of mice. Sixty DBA/2 breeding pairs were used for this experiment. Animals were kept in three rack systems: a ventilated cabinet, a normal open rack and an individually ventilated cage rack (IVC rack) with enriched or non-enriched type II elongated Makrolon cages. Reproduction performance was recorded from 10 to 40 weeks of age. In all three rack systems there was a similar breeding index (pups/dam/week) in non-enriched groups during the long-term breeding period, but the coefficients of variation in the IVC rack were higher for most parameters. This type of enrichment seems to lead to a decrease in the number of pups born, especially in the IVC group. However, there was no significant difference in breeding index (young weaned/female/week).
Higher heart rate of laboratory mice housed individually vs in pairs
Authors: Späni D. , Arras M. , König B. , Rülicke T.
Published: February 2003

Many studies have shown that housing mice individually over a long period significantly alters their physiology, but in most cases measurement has required human interference and restraint for sampling. Using a radio-telemetry system with implantable transmitters, we recorded heart rate (HR), motor activity (ACT) and body temperature (BT) of freely moving male mice (NMRI) housed either individually or in pairs with an ovarectomized female. Data for each parameter were collected at 5 min intervals for two consecutive 24 h periods. Even after several weeks of habituation to the social conditions, HR was increased in mice housed individually compared with mice housed in pairs, although their measured ACT did not differ. Additionally, BT tended to be reduced in individually-housed mice. When the data were analysed according to different ACT levels, HR was increased in individually-housed mice during phases of low and high, but not intermediate, motor activity. Furthermore, individually-housed mice had more, but shorter, resting bouts, indicating disruption of the normal circadian sleep pattern. Enhanced HR in individually-housed mice does not necessarily indicate stress, but might be an important physiological indicator of discomfort. The fact that individual housing alters basic physiological parameters in laboratory mice highlights the need to control for housing-dependent variation, especially in experiments that are sensitive to changes in these parameters.
Subsensitivity to beta-adrenergic stimulation in atria from rats infested with Syphacia sp.
Authors: Silveira Ana Carolina , Gilioli Rovilson , Oliveira Elizângela S. , Bassani Rosana A.
Published: February 2003

Syphacia sp. is a common intestinal parasite in conventionally-housed laboratory rodents. Although gross lesions are rare in oxyuriasis, it is possible that more subtle changes may develop, which may affect research results. In this study, we analysed the responsiveness to β-adrenergic stimulation by isoproterenol (ISO) of left atria isolated from Syphacia-infested (SYPH) and control, non-infested adult male Wistar rats (CONT). In the non-infested animals, ISO pD2 was not significantly changed by ivermectin treatment. Whereas the maximal inotropic response to ISO was not significantly affected, the pD2 value was decreased in SYPH (7.61 ± 0.09, n = 7, vs 8.21 ± 0.25 in CONT, n = 5, P < 0.05), indicating lower sensitivity to β-adrenergic stimulation. This change was similar to that caused by a classic stressor, namely repeated immobilization, in non-infested rats (IMMO). In this group, ISO pD2 was 7.62 ± 0.14, n = 6 ( P < 0.05 with relation to CONT). The results indicate that infestation with Syphacia sp. is as effective as immobilization at diminishing cardiac reactivity to β-adrenergic stimulation. It is thus possible that oxyuriasis may affect the response of other tissues to physiological modulators.
A simple procedure to perform intravenous injections in the Mongolian gerbil (Meriones unguiculatus)
Authors: Pérez-García C. C. , Peña-Penabad M. , Cano-Rábano M. J. , García-Rodríguez M. B. , Gallego-Morales D. , Ríos-Granja M. A. , Diez-Prieto I.
Published: February 2003

We describe a simple and feasible procedure for performing intravenous administration of substances in the gerbil. Under light anaesthesia, animals were held in dorsal recumbency and a very small incision of skin, parallel to the femoral vein on the internal side of the thigh, was made. The vein is easily accessible via thin skin incision. An insulin syringe and a 30G needle were used for the injection. This is an easy and quick method, which, with appropriate anaesthesia, allows rapid recovery.
Titelbild: Facile Solid‐State Synthesis of Highly Conducting Poly(ethylenedioxythiophene) (Angew. Chem. 6/2003)
Authors: Meng Hong , Perepichka Dmitrii F. , Wudl Fred
Published: February 2003

Die Festkörpersynthese eines leitfähigen Polymers gelang durch vorsichtiges Erhitzen von 2,5‐Dibrom‐3,4‐ethylendioxythiophen, in dessen farblosen Kristallen ein intermolekularer Br‐Br‐Abstand von nur 3.45 Å vorliegt. Die schwarzen, Br‐dotierten Poly(3,4‐ethylendioxythiophen)‐Kristalle zeigen eine Leitfähigkeit von immerhin 80 S cm−1. Auch dünne Filme des leitfähigen Polymers lassen sich leicht erzeugen. Mehr darüber erfahren Sie in der Zuschrift von Wudl et al. auf Seite 682 ff.
Biomineralisation von Einzellern: eine außergewöhnliche Membranbiochemie zur Produktion anorganischer Nano‐ und Mikrostrukturen
Authors: Bäuerlein Edmund
Published: February 2003

Die Natur hat es im Laufe ihrer Entwicklung mit einzigartiger Erfindungsgabe verstanden, auch anorganische Strukturen in vielfältigen Formen zu bilden. Jede Art, die biogene Mineralien hervorbringt, erzeugt diese in einer für sie spezifischen Form, die demnach offensichtlich biologisch kontrolliert ist. Es wird angenommen, dass sowohl die Synthese als auch die Form eines jeden biogenen Materials genetisch programmiert und gesteuert sind. Dies zu untersuchen und die Mechanismen der Biomineralisation zu beschreiben ist erst möglich geworden, seitdem moderne Methoden in der Biologie zu Verfügung stehen. Einzeller wie magnetische Bakterien, Kalkalgen und Kieselalgen, die zu den einfachsten Lebewesen gehören, eignen sich in besonderem Maße, mit diesen Methoden untersucht zu werden. In ihnen entstehen Kristalle und Verbundmaterialien aus Proteinen und amorphen anorganischen Polymeren, welche in der anorganischen Chemie bis heute unbekannt sind.
Cover Picture: Facile Solid‐State Synthesis of Highly Conducting Poly(ethylenedioxythiophene) (Angew. Chem. Int. Ed. 6/2003)
Authors: Meng Hong , Perepichka Dmitrii F. , Wudl Fred
Published: February 2003

The solid‐state synthesis of a conducting polymer was achieved by gentle heating of 2,5‐dibromo‐3,4‐ethylenedioxythiophene, the colorless crystals of which are characterized by intermolecular BrBr contacts of just 3.45 Å. The bromine‐doped black poly(3,4‐ethylenedioxythiophene) crystals show a high conductivity of 80 S cm−1. Thin films of the conducting polymer can also be easily fabricated. For more information see the communication by Wudl et al. on page 658 ff.