bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of binding stoichiometries of the human immunodeficiency virus type 1 reverse transcriptase by capillary electrophoresis and laser‐induced fluorescence polarization using aptamers as probes
Authors: Fu Hao , Guthrie Jeffrey W. , Le X. Chris
Published: December 2005

Binding stoichiometries between four DNA aptamers (RT12, RT26, RTlt49, and ODN93) and the reverse transcriptase (RT) of the type 1 human immunodeficiency virus (HIV‐1) were studied using affinity CE (ACE) coupled with LIF polarization and fluorescence polarization (FP). The ACE/LIF study showed evidence of two binding stoichiometries between the HIV‐1 RT protein and aptamers RT12, RT26, and ODN93, suggesting that these aptamers can bind to both the p66 and p51 subunits of the HIV‐1 RT. Only one binding stoichiometry for aptamer RTlt49 was found. The affinity complexes were easily separated from the unbound aptamers; however, the different stoichiometries were not well resolved. A complementary technique, FP, was able to provide additional information about the binding and supporting evidence for the ACE/LIF results. The ACE/LIFP study also revealed that the FP values of the 1:1 complexes of the HIV‐1 RT protein with aptamers RT12, RT26, and ODN93 were always much greater than those of the 1:2 complexes. This was initially surprising because the larger molecular size of the 1:2 complexes was expected to result in higher FP values than the corresponding 1:1 complexes. This phenomenon was probably a result of fluorescence resonance energy transfer between the two fluorescent molecules bound to the HIV‐1 RT protein.
New universal primers facilitate Pyrosequencing™
Authors: Aydin Atakan , Toliat Mohammad R. , Bähring Sylvia , Becker Christian , Nürnberg Peter
Published: December 2005

A cost‐driving factor in Pyrosequencing™ is the need for single‐stranded PCR products that are usually obtained by biotin‐labeling of one primer. We designed new universal primers that allow the introduction of biotin during the specific PCR at either the forward or the reverse primer in a single reaction. When converting five human single nucleotide polymorphism assays from the standard format into the universal format, we obtained pyrograms of similar good quality. Although the universal nonhuman sequences are unlikely to form loop structures, we mostly failed to establish assays without using the proprietary software from Biotage AB. Nevertheless, our universal primer pair adds flexibility to the process of assay design due to optional strand selection and contributes to the reduction of genotyping costs.
Forward‐in‐time upwind‐weighted methods in ocean modelling
Authors: Hecht Matthew W.
Published: December 2005

The World Ocean presents a remarkably wide range of spatial and temporal scales within complicated domains. At larger scales, beyond a few tens of meters, the ocean circulation can be seen to separate into quasi‐horizontal and vertical directions, with the magnitude of mixing differing by many orders of magnitude between the two. It is within this context, and with additional constraints of flux‐conservation when used for coupled climate simulation, that transport schemes are placed within ocean general circulation models.

Forward‐in‐time upwind‐weighted methods have made gradual, steady inroads into the field. We review this evolution from centred‐in‐time centred‐in‐space schemes, first discussing temporally hybrid models (centred discretization of the momentum equations with forward‐in‐time treatment of the scalar transport equations), then fully forward‐in‐time models, touching on a number of test problems and analyses that have provided guidance to these model development efforts and discussing selected results. Copyright © 2005 John Wiley & Sons, Ltd.
Performance‐based budgeting in the public sector: an illustration from the VA health care system
Authors: Yaisawarng Suthathip , Burgess James F.
Published: December 2005

This paper estimates frontier cost functions for US Department of Veterans Affairs (VA) hospitals in FY2000 that are consistent with economic theory and explicitly account for cost differences across patients' risk, level of access to care, quality of care, and hospital‐specific characteristics. Results indicate that on average VA hospitals in FY2000 operate at efficiency levels of 94%, as compared to previous studies on US private sector hospitals that average closer to 90% efficient. Using these cost frontiers, management systems potentially could be implemented to enhance the equitable allocation of the VA medical care global budget and systematically distribute funds across hospitals and networks. The paper also provides recommendations to improve the efficiency of delivering health care services applicable to public sector organizations. Copyright © 2005 John Wiley & Sons, Ltd.
Ginkgo biloba: no robust effect on cognitive abilities or mood in healthy young or older adults
Authors: Burns Nicholas R. , Bryan Janet , Nettelbeck Ted
Published: December 2005

Ginkgo biloba extracts are commonly used to prevent or treat memory problems but evidence on the efficacy of ginkgo is equivocal. In any case, the psychological locus of ginkgo's effects is unknown. A 12‐week, double‐blind, placebo‐controlled study assessed effects of ginkgo (120 mg per day) on a wide range of cognitive abilities, executive function, attention and mood in 93 healthy older adults (55–79 years) and in 104 young adults (18–43 years). For the older adult sample, longer‐term memory assessed by associational learning tasks showed improvement with ginkgo (d = 0.52, p = 0.04). There was no statistically significant difference on any other measure. For the young adult group no measure showed statistically significant effects of ginkgo enhancement. There were no side effects unequivocally attributable to treatment with ginkgo and those reported by participants in the ginkgo groups were mild and similar to those reported elsewhere. Copyright © 2005 John Wiley & Sons, Ltd.
Tamoxifen and contralateral breast cancer in BRCA1 and BRCA2 carriers: An update
Authors: Gronwald Jacek , Tung Nadine , Foulkes William D. , Offit Kenneth , Gershoni Ruth , Daly Mary , Kim‐Sing Charmaine , Olsson Hakan , Ainsworth Peter , Eisen Andrea , Saal Howard , Friedman Eitan , Olopade Olufunmilayo , Osborne Michael , Weitzel Jeffrey , Lynch Henry , Ghadirian Parviz , Lubinski Jan , Sun Ping , Narod Steven A. ,   The Hereditary Breast Cancer Clinical Study Group
Published: December 2005

Women with a mutation in BRCA1 or BRCA2 face a lifetime risk of breast cancer of ∼80%, and following the first diagnosis the10‐year risk of contralateral breast cancer is ∼30%. It has been shown that both tamoxifen and oophorectomy prevent contralateral breast cancer, but it is not clear whether there is a benefit in giving tamoxifen to women who have previously undergone an oophorectomy. Furthermore, the relative degree of protection in BRCA1 and BRCA2 carriers has not been well evaluated. We studied 285 women with bilateral breast cancer and a BRCA1 or BRCA2 mutation, and 751 control women with unilateral breast cancer and a BRCA1 or BRCA2 mutation in a matched case‐control study. Control women were of similar age and had a similar age of diagnosis of breast cancer and had been followed for as long as the case for a second primary breast cancer. The history of tamoxifen use for treating the first breast cancer was compared between bilateral and unilateral cases. The multivariate odds ratio for contralateral breast cancer associated with tamoxifen use was 0.50 for carriers of BRCA1 mutations (95% CI, 0.30–0.85) and was 0.42 for carriers of BRCA2 mutations (95% CI, 0.17–1.02). The protective effect of tamoxifen was not seen among women who had undergone an oophorectomy (OR = 0.83; 95%CI, 0.24–2.89) but this subgroup was small. In contrast, a strong protective effect of tamoxifen was apparent among women who were premenopausal or who had undergone natural menopause (OR = 0.44; 95% CI, 0.27–0.65). © 2005 Wiley‐Liss, Inc.
Human tongue carcinoma growth is inhibited by selective antigelatinolytic peptides
Authors: Heikkilä Pia , Suojanen Juho , Pirilä Emma , Väänänen Anu , Koivunen Erkki , Sorsa Timo , Salo Tuula
Published: December 2005

Matrix metalloproteinases (MMP‐2 and MMP‐9, or gelatinases) are involved in tongue SCC invasion, metastasis and angiogenesis. We have recently shown that a novel and selective hydrophobic cyclic CTTHWGFTLC (CTT1) peptide is inhibitor for MMP‐2 and MMP‐9 (Koivunen et al., Nat Biotechnol 1999; 17:768–74). In this study, we demonstrate that both the new hydrophilic derivate GRENYHGCTTHWGFTLC (CTT2) peptide and the CTT1 peptide inhibited specifically the human tongue squamous cell carcinoma (HSC‐3) cell‐derived gelatinolytic activity and in vitro invasion and migration of these cells (p ≤ 0.049). In situ zymography revealed that both peptides also inhibited clearly almost all of the gelatinolytic activity present in the human tongue SCC tissue sections, indicating that MMP‐2 and MMP‐9 are the major gelatinases detected in the tongue carcinomas. However, CTT2 did not inhibit the type I collagen degradation by human collagenases (MMP‐1, MMP‐8 and MMP‐13). Furthermore, CTT2 reduced the blood vessel density (p ≤ 0.043) and clearly improved the survival of the mice bearing human tongue carcinoma xenografts (p ≤ 0.012). Overall, we suggest that CTT1 and CTT2 peptides being selective gelatinase inhibitors with significant anti‐tumor properties could be useful to diminish the invasion and angiogenesis of human tongue carcinomas characterized by enhanced gelatinolytic activity in tumors. © 2005 Wiley‐Liss, Inc.
Confirmation of a linkage between H‐Ras and MMP‐13 expression as well as MMP‐9 by chemical genomic approach
Authors: Lee Su‐Kyung , Kim Jung Min , Lee Mi‐Young , Son Kwang‐Hee , Yeom Young Il , Kim Cheol‐Hee , Shin Youseung , Koh Jong Sung , Han Dong Cho , Kwon Byoung‐Mog
Published: December 2005

As farnesylation of the Ras protein by farnesyl transferase is a critical step for the Ras functional activity, the farnesyl transferase inhibitor could affect H‐Ras functions and the inhibitors such as arteminolide, SCH66336 and LB42908 completely inhibited Ras‐farnesylation. However, they did not induce apoptosis of H‐Ras‐transformed cells with concentration for blocking H‐Ras farnesylation. To determine the antitumor effects of the inhibitors, it was analyzed through the expression profile of genes, regulated by activated H‐Ras or FTIs by using cDNA microarray. On the basis of the results, the relationship between H‐Ras and MMPs expression was confirmed by RT‐PCR, Western bolt, zymographic analysis and angiogenesis assay. Our results suggested that activation of MMP‐13 as well as MMP‐9 induced by H‐Ras is involved in angiogenesis and with farnesyl transferase inhibitors, in part, exerts their anticancer effects. We confirmed that MMP‐13 is a critical H‐Ras target gene through chemical genomic approaches with farnesyl transferase inhibitors. © 2005 Wiley‐Liss, Inc.
Telomerase inhibition by stable RNA interference impairs tumor growth and angiogenesis in glioblastoma xenografts
Authors: Pallini Roberto , Sorrentino Antonio , Pierconti Francesco , Maggiano Nicola , Faggi Riccardo , Montano Nicola , Maira Giulio , Larocca Luigi Maria , Levi Andrea , Falchetti Maria Laura
Published: December 2005

Telomerase is highly expressed in advanced stages of most cancers where it allows the clonal expansion of transformed cells by counteracting telomere erosion. Telomerase may also contribute to tumor progression through still undefined cell growth‐promoting functions. Here, we inhibited telomerase activity in 2 human glioblastoma (GBM) cell lines, TB10 and U87MG, by targeting the catalytic subunit, hTERT, via stable RNA interference (RNAi). Although the reduction in telomerase activity had no effect on GBM cell growth in vitro, the development of tumors in subcutaneously and intracranially grafted nude mice was significantly inhibited by antitelomerase RNAi. The in vivo effect was observed within a relatively small number of population doublings, suggesting that telomerase inhibition may hinder cancer cell growth in vivo prior to a substantial shortening of telomere length. Tumor xenografts that arose from telomerase‐inhibited GBM cells also showed a less‐malignant phenotype due both to the absence of massive necrosis and to reduced angiogenesis. © 2005 Wiley‐Liss, Inc.
Steroid hormones stimulate human prostate cancer progression and metastasis
Authors: Ricke William A. , Ishii Kenichiro , Ricke Emily A. , Simko Jeff , Wang Yuzhuo , Hayward Simon W. , Cunha Gerald R.
Published: December 2005

Tissue recombinants (TRs) composed of mouse urogenital mesenchyme (mUGM) plus an immortalized nontumorigenic human prostatic epithelial cell line (BPH‐1) were grown under the kidney capsule of male athymic nude mice under different hormonal conditions. The objectives were to determine temporal plasma concentrations of testosterone (T) and estradiol‐17β (E2) that elicit progression of nontumorigenic human prostatic epithelial cells in vivo. Second, to determine whether mUGM+BPH‐1 TRs in [T+E2]‐treated hosts could progress to metastases. Control mouse hosts received no exogenous hormonal support, whereas treated mice received Silastic implants containing T and E2 for 1–4 months. Plasma from hormonally treated mice contained significantly higher (p < 0.01) concentrations of T at 1 month (11.7 vs. 0.9 ng/ml). Plasma levels of E2 in steroid implanted mice were significantly higher (p <0.05) at 2 months (104.5 vs. 25.6 ng/l) and 4 months (122.8 vs. 19.2 pg/ml). Wet weights of mUGM+BPH‐1 TRs from [T+E2]‐implanted mice were significantly larger (p < 0.001) than those from untreated hosts. Untreated mUGM+BPH‐1 TRs contained a well organized differentiated epithelium surrounded by smooth muscle stroma similar to developing prostate. In [T+E2]‐implanted mice, mUGM+BPH‐1 TRs formed carcinomas that contained a fibrous connective tissue stroma permeating the tumor; smooth muscle when present was associated with vasculature. Renal lymph nodes collected from [T+E2]‐treated mice, but not untreated mice, contained metastatic carcinoma cells. Moreover, metastases could be observed at distant sites including lung and liver. Epithelial cells isolated from untreated mUGM+BPH‐1 TRs exhibited benign histology and formed small nontumorigenic grafts when subsequently transplanted into athymic nude mice. In contrast, epithelial cells isolated from mUGM+BPH‐1 tumors of [T+E2]‐treated hosts formed large tumors that grew independent of stromal and hormonal support and developed lymph node metastases. We conclude that [T+E2]‐treatment promotes prostatic cancer progression in mUGM + BPH‐1 TRs. Use of mUGM in this system will allow future studies to utilize the power of mouse genetics to identify paracrine factors involved in human prostatic carcinogenesis. © 2005 Wiley‐Liss, Inc.
A prostate secretory protein94‐derived synthetic peptide PCK3145 inhibits VEGF signalling in endothelial cells: Implication in tumor angiogenesis
Authors: Lamy Sylvie , Ruiz Marcia T. , Wisniewski Jan , Garde Seema , Rabbani Shafaat A. , Panchal Chandra , Wu Jinzi J. , Annabi Borhane
Published: December 2005

We have previously observed that the synthetic peptide corresponding to amino acids 31–45 (PCK3145) of PSP94 can reduce prostate tumor growth in vivo. Moreover, a recently concluded phase IIa clinical trial with patients with hormone refractory prostate cancer indicated that PCK3145 down‐regulates the levels of plasma matrix metalloproteinase (MMP)‐9, a MMP involved in metastasis and tumor angiogenesis. The purpose of our study was to investigate the molecular mechanisms of action of PCK3145 and whether this peptide could antagonize tumor neovascularization. We show that, in a syngeneic in vivo model of rat prostate cancer, the expression of endothelial cell (EC) specific CD31, a marker of tumor vessel density, was decreased by 43% in PCK3145‐treated animals. In vitro, PCK3145 specifically antagonized in a dose‐dependent manner the VEGF‐induced ERK phosphorylation as well as the phosphorylation of the VEGFR‐2 in cultured EC (HUVEC). These anti‐VEGF effects were partly reproduced by pharmacological inhibitors such as PD98059 and PTK787, suggesting that PCK3145 inhibits the tyrosine kinase activity associated to VEGFR‐2, which in turn prevents intracellular signalling through the MAPK cascade. Moreover, PCK3145 was also found to inhibit the PDGF‐induced phosphorylation of PDGFR in smooth muscle cells. Finally, PCK3145 inhibited in vitro EC tubulogenesis and VEGF‐induced MMP‐2 secretion suggesting its potential implication as an antiangiogenic agent. Our study demonstrates that PCK3145 interferes with the tyrosine kinase activity associated with VEGF signalling axis in EC. The antiangiogenic properties of this peptide could be highly beneficial and exploited in novel antiangiogenic therapies, for patients with various cancers. © 2005 Wiley‐Liss, Inc.
Short‐term dietary administration of celecoxib enhances the efficacy of tumor lysate‐pulsed dendritic cell vaccines in treating murine breast cancer
Authors: Hahn Tobias , Alvarez Irene , Kobie James J. , Ramanathapuram Lalitha , Dial Sharon , Fulton Amy , Besselsen David , Walker Edwin , Akporiaye Emmanuel T.
Published: December 2005

Cyclooxygenase‐2 (COX‐2) is a rate‐limiting enzyme in the synthesis of prostaglandins. It is over‐expressed in multiple cancers and has been associated with diminished tumor immunity. Dendritic cells (DCs) are considered candidates for cancer immunotherapy due to their ability to process and present antigens to T cells and stimulate immune responses. However, DC‐based vaccines have exhibited minimal effectiveness against established tumors. In this study, we evaluated the effect of short‐term administration of the selective COX‐2 inhibitor celecoxib on the efficacy of DC‐based vaccines in preventing and treating established 4T1 murine mammary tumors. We show that dietary celecoxib alone significantly suppresses the growth of primary tumors and the incidence of lung metastases in the prophylactic setting but is less effective against pre‐established tumors. However, we demonstrate that celecoxib administered after primary tumor establishment synergizes with tumor lysate‐pulsed DC and the adjuvant, GM‐CSF, to improve the antitumor immune response by suppressing primary tumor growth and markedly reducing the occurrence of lung metastases. This triple combination therapy elicits a tumor‐specific immune response evidenced by elevated IFN‐γ and IL‐4 secretion by CD4+ T cells and results in increased infiltration of CD4+ and CD8+ T cells to the tumor site. In addition, dietary celecoxib inhibits angiogenesis evidenced by decreased vascular proliferation within the tumor and serum vascular endothelial growth factor levels. These studies suggest that short‐term celecoxib therapy in combination with DC vaccines may be safely used for treating metastatic breast cancer. © 2005 Wiley‐Liss, Inc.
Serological analysis of human renal cell carcinoma
Authors: Devitt Gerard , Meyer Christiane , Wiedemann Nicole , Eichmüller Stefan , Kopp‐Schneider Annette , Haferkamp Axel , Hautmann Richard , Zöller Margot
Published: December 2005

Serological analysis of cDNA expression libraries (SEREX) has proven to be a useful technique in the quest to elucidate the repertoire of immunogenic gene products in human cancer. We have applied the SEREX method to human renal cell carcinoma (RCC) in order to identify associated immunogenic gene products. cDNA expression libraries were prepared from a RCC tumor, a RCC cell line and human testis. The 3 libraries were screened with sera from 35 RCC patients and 15 healthy controls. Approximately 4.5 × 106 phage plaques were screened resulting in 234 positive clones, which corresponded to 74 different gene products. The seroreactivity toward 49 of these antigens was assessed. Seroreactivity to 21 (43%) of the antigens was similar in RCC patients and healthy controls, 9 antigens (18%) elicited antibodies more frequently and 19 antigens (39%) solely in RCC patients. In the reverse setting, reactivity of RCC patients' sera was tested against a panel of 44 previously identified “tumor‐associated” antigens via the SADA (serum antibody detection array) method; 6 antigens reacted with RCC patients' and healthy donors' sera, 8 were reactive only with RCC patients' sera. From the 27 antigens identified by SEREX and SADA, which did not react with sera from healthy controls, 10 antigens reacted with a significant proportion of RCC patients' sera and 77% of RCC patients' sera reacted at least with one of these antigens. Sera from patients with non‐malignant renal diseases or an autoimmune disease did not react with these 10 antigens. © 2005 Wiley‐Liss, Inc.
Predominant T helper type 2‐inflammatory responses promote murine colon cancers
Authors: Osawa Emi , Nakajima Atsushi , Fujisawa Toshio , Kawamura Yuki I. , Toyama‐Sorimachi Noriko , Nakagama Hitoshi , Dohi Taeko
Published: December 2005

Colon cancer is one of the most serious complications of inflammatory bowel diseases, especially ulcerative colitis (UC). Previous studies have shown that characteristic immunological event during inflammation in UC is the expression of T helper‐type 2 (Th2) cell‐derived cytokines. In this study, we investigated the influence of a predominant Th2‐type cytokine response in colitis on carcinogen‐induced colon tumors. Wild type (WT), interferon gamma (IFN‐γ) gene deficient (−/−) [Th2 dominant] or interleukin (IL)‐4−/− [Th1‐dominant] mice of BALB/c background were used in this study. To compare tumor formation, mice were given the carcinogen azoxymethane (AOM) and intrarectal administration of trinitrobenzene sulfonic acid (TNBS), to induce colitis. Thirty‐three weeks after initial treatment, the total colon was examined. When IFN‐γ−/− mice were treated with AOM and TNBS, significantly higher number of tumors were seen (8.4 ± 1.7) than in WT (3.3 ± 2.9) or IL‐4−/− (3.1 ± 3.4) mice, which received identical treatments. A separate set of experiment, using less doses of AOM and TNBS also showed the higher frequency of tumor formation in IFN‐γ−/− mice than in IL‐4−/− mice. Histologically, the tumors were well‐ or moderately‐differentiated adenocarcinomas. No invasion into the submucosal or serosal layers of the intestine was seen. In immunohistological staining, some tumors in IFN‐γ−/− mice showed distinct nuclear expression of β‐catenin, in contrast to the strong membrane staining seen in tumors of IL‐4−/− mice. In conclusion, colonic inflammation associated with Th2‐donimant cytokine responses enhanced the formation of malignant neoplasms. © 2005 Wiley‐Liss, Inc.
Commercial cows' milk has uterotrophic activity on the uteri of young ovariectomized rats and immature rats
Authors: Ganmaa Davaasambuu , Tezuka Hideo , Enkhmaa Davaasambuu , Hoshi Kazuhiko , Sato Akio
Published: December 2005

Cows' milk contains considerable quantities of estrogens, mainly in the form of estrone sulfate (ES). To determine whether the commercial milk has any biologically significant hormonal effects, 2 series of uterotrophic tests were performed, 1 with young ovariectomized rats and the other with sexually immature rats. Thirty‐six rats were used for each test. They were divided into 3 groups of 12 animals each, and were kept for 7 days on powdered chow with 1 of 3 drinking solutions: low‐fat milk (LFM), artificial milk (AM, negative control), or AM containing ES at 100 ng/ml (positive control). At autopsy, both the wet and blotted uterine weights were measured. The cell heights of uterine epithelia in ovariectomized rats were also determined. The significance of differences among groups was tested by Dunnett's multiple comparisons test. In each test, the weights of the uteri in the LFM group were significantly greater than those of the respective weights in the AM group (p < 0.01). Furthermore, in ovariectomized rats, the uterine epithelial‐cell height in the LFM group was significantly greater than that observed in the AM group (p < 0.01). The uterotrophic effect of 100 ng/ml ES solution was greater than that of LFM in immature rats (p < 0.01), whereas the effect of the solution was almost comparable to that of LFM in young ovariectomized rats (p > 0.05). In conclusion, commercially available milk has uterotrophic effects in both young ovariectomized rats and sexually immature rats. © 2005 Wiley‐Liss, Inc.
Gastric cancer screening and subsequent risk of gastric cancer: A large‐scale population‐based cohort study, with a 13‐year follow‐up in Japan
Authors: Lee Kyung‐Jae , Inoue Manami , Otani Tetsuya , Iwasaki Motoki , Sasazuki Shizuka , Tsugane Shoichiro
Published: December 2005

We prospectively investigated the association between gastric cancer screening and subsequent risk of gastric cancer in a large‐scale population‐based prospective cohort study, with a 13‐year follow‐up in Japan. Data were analyzed from a population‐based cohort of 42,150 (20,326 men and 21,824 women) subjects. Approximately 36% of subjects reported that they had undergone screening photofluorography during the preceding 12 months, and were regarded as the screened group. A total of 179 gastric cancer deaths and 636 incident gastric cancers were identified during the follow‐up period. We observed a 2‐fold decrease in gastric cancer mortality in screened versus unscreened subjects (RR = 0.52; 95% CI = 0.36–0.74). The extent of the reduction in mortality for gastric cancer was greater than in death from all causes excluding gastric cancer (RR = 0.71; 95% CI = 0.65–0.78). A significant decrease in the incidence of advanced gastric cancer was observed in screened subjects (RR = 0.75; 95% CI = 0.58–0.96), although the overall incidence rate did not differ significantly between the screened and unscreened subjects (RR = 1.06; 95% CI = 0.90–1.25). In age‐stratified analyses, a significant reduction in gastric cancer mortality was seen in screened subjects aged 40–49 years at baseline, compared with a lesser reduction in screened subjects aged 50–59 (RR = 0.30, 95% CI = 0.13–0.72; and RR = 0.60, 95% CI = 0.40–0.88, respectively). These findings suggest that gastric cancer screening may be associated with a reduced risk of mortality from gastric cancer. © 2005 Wiley‐Liss, Inc.
Preparation and characterization of RF magnetron sputtered calcium pyrophosphate coatings
Authors: Yonggang Yan , Wolke J.G.C. , Yubao Li , Jansen J.A.
Published: December 2005

CaP ceramic has been widely used as coating on metals in orthopedics and oral dentistry. Variations in CaP composition can lead to different dissolution/precipitation behavior and may also affect the bone response. In the present study calcium pyrophosphate and hydroxylapatite coatings were successfully prepared by RF magnetron sputtering deposition. The phase composition, morphological properties, and the dissolution in SBF were characterized by using XRD, FTIR, EDS, SEM, and spectrophotometry. The results showed that all the sputtered coatings were amorphous and changed into a crystal structure after IR‐radiation. The temperature for the crystallization of the amorphous coatings is lower for the hydroxylapatite coating (550°C), compared to the calcium pyrophosphate coating (650°C). All sputtered amorphous coatings were instable in SBF and dissolved partially within 4 wks of incubation. The heat‐treated coatings appeared to be stable after incubation. These results showed that magnetron sputtering of calcium pyrophosphate coating is a promising method for forming a biocompatible ceramic coating. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Directional/acidic dissolution kinetics of (OH,F,Cl)‐bearing apatite
Authors: Tseng Wan‐Ju , Lin Chung‐Cherng , Shen Po‐Wen , Shen Pouyan
Published: December 2005

Directional dissolution of a natural (OH,F,Cl)‐bearing apatite has been studied at various solution pH values (0–3) and 30°C. This apatite showed abnormally high OH stretching frequencies due to the substitution of Cl for OH. The advance of dissolution front indicated that steady‐state directional dissolution for pH = 0–2 followed an apparent rate law of Rate = ka (in mole/m2h), where the rate constants (k) are 2.15 and 1.61; and the rate orders (n) are 1.44 and 1.30 for [0001] and <1120> directions, respectively. Previous study, however, indicated a smaller n value (n = 0.55–0.70) for fluorapatite powders at higher pHs. A nonlinear pH dependence of logarithmic dissolution rate at a wide pH range implied that the surface active sites and/or rate‐determining steps have changed when the acidity of solution and/or the composition of the apatite were changed. The opening of etch pits on basal planes further indicated that the dissolution rates along the three principal directions have the following relationship: [0001] > <1120> > <1010> for pH=0–1, but the order was reversed for pH > 3. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
The influence of functional groups of self‐assembled monolayers on fibrous capsule formation and cell recruitment
Authors: Barbosa Judite N. , Madureira Pedro , Barbosa Mário A. , Águas Artur P.
Published: December 2005

The contribution of the surface chemistry of an implant to the thickness of the fibrous capsule formed after implantation was herein investigated. For that, self‐assembled monolayers (SAMs) of alkanethiols on gold with different terminal functional groups (COOH, OH, and CH3) were used. These surfaces were implanted in subcutaneous air pouches of BALB/c mice and the ensuing fibrous capsules were evaluated and compared with the initial inflammatory response caused by the implant. The thickness of the fibrous capsules that are under organization around the implant was measured 1 week after implantation by histology. Inflammatory exudates were collected from the air pouches 24 h after the implantation of SAMs and were analyzed by flow cytometry. A significant increase in the thickness of fibrous capsules was seen around implanted CH3‐terminated SAMs, and also in gold surfaces, in comparison with the air pouch wall of sham‐operated mice and of COOH‐ and OH‐covered SAMs. The CH3‐coated implants also recruited higher numbers of inflammatory cells; this enhancement involved a significant number of Mac‐1+ cells. Our data indicate that implant surfaces coated with CH3 induce thick fibrous capsules and this may be the result of the stronger inflammatory effect of CH3 in comparison with COOH or OH chemical groups. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Effect of an acidulated fluoride etchant on bonding between titanium and two luting materials
Authors: Yang Lei , Taira Yohsuke , Atsuta Mitsuru
Published: December 2005

Adhesive bonding between resin and titanium is useful for resin‐bonded prostheses. The purpose of this study was to investigate the efficacy of an etchant, consisting of ammonium hydrogen fluoride (AHF) and phosphoric acid (PA), in titanium bonding. Cast specimens of commercially pure titanium were air‐abraded with alumina and etched for 30 s, after which a primer (ALP) was applied. An acrylic rod was bonded to the specimen with one of the two luting agents being examined (Super‐Bond QUICK and Panavia F2.0). Shear bond strengths were determined following 10,000 thermocycles. When Panavia F2.0 was applied, neither the etchant nor the ALP primer showed significant effect on bond strength. The postthermocycling bond strength of Super‐Bond QUICK was significantly improved with the use of an etchant and ALP primer. Although microscopic observation revealed that considerable numbers of submicron pits were created on the specimens etched using AHF with PA, no significant difference in bond strength was detected in the application of AHF, with or without PA. The present findings suggested that the improved bonding durability was due to the micromechanical retention between the resin and the microscopically roughened titanium surface. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
A theoretical study of thermal [1,3]‐sigmatropic rearrangements of 3‐trimethylsilyl‐1‐pyrazoline: Concerted vs. stepwise mechanisms
Authors: Lim Chultack , Lee Hee Soon , Kwak Young‐Woo , Choi Cheol Ho
Published: December 2005

Possible reaction mechanisms of 1,3‐silyl and 1,3‐hydrogen thermal rearrangements of trimethylsilyl‐1‐pyrazoline and its model systems were theoretically explored using B3LYP, MP2, CR‐CCSD(T), CASSCF(6,5), and MRMP2(6,5) theories. Nitrogen substitution at the center position of allylic moiety turned out to have a special stabilizing effect on diradical intermediates, allowing a stepwise pathway. This substitutional effect was attributed to the nitrogen lone pair electrons, which form strong π‐conjugations with diradicals. The second nitrogen substitution at the terminal allylic position selectively reduces the reaction barrier of antarafacial retention pathway, creating a competition between concerted and stepwise channels. The introduction of a five‐membered ring imposes ring strain on the allylic moiety and increases steric hindrance, allowing no antarafacial channels. The combined effect of the nitrogen substitution and the five‐membered ring further removes the possibility of concerted reaction pathways. Therefore 1,3‐silyl migrations of 3‐trimethylsilyl‐1‐pyrazoline were found to occur only through stepwise mechanisms, implying that the Woodward–Hoffmann rule is not operative. The 1,3‐hydrogen migration also occur via a stepwise mechanism; however, it would not occur easily because its reaction barrier is much higher than that of 1,3‐silyl migrations. Current study shows that a stepwise mechanism can be the dominant reaction pathway of some particular [1,3]‐sigmatropic rearrangements. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 228–237, 2006
RETRACTED: Nuclear clusterin accumulation during heat shock response: Implications for cell survival and thermo‐tolerance induction in immortalized and prostate cancer cells
Authors: Caccamo Alessandro E. , Desenzani Silvia , Belloni Lucia , Borghetti Angelo F. , Bettuzzi Saverio
Published: December 2005

Clusterin (CLU), whose role is still debated, is differentially regulated in several patho‐physiological processes and invariably induced during apoptosis. In heat shock response, CLU is considered a stress‐inducible, pro‐survival/cyto‐protective factor via an HSE element present in his promoter. In both human prostate PNT1A and PC‐3 epithelial cells we found that apoptotic stimuli induced nuclear localization of CLU (nCLU), and that overexpression of nCLU is pro‐apoptotic. We show here that CLU time‐course accumulation kinetic is different from that of HSP70 in these cells, thus other factor(s) might mediate HSF‐1 activation and CLU expression. Sub‐lethal heat shock inhibited the secretion of CLU (sCLU), leading to increased cytoplasm accumulation of CLU (cCLU) in association to cell survival. At difference, lethal heat stress caused massive accumulation of pro‐apoptotic nCLU in cells dying by caspase‐3‐dependent apoptosis. Double heat stress (sub‐lethal heat shock followed by recovery and lethal stress) induced HSP70 and thermo‐tolerance in PNT1A cells, but not in PC‐3 cells. In PNT1A cells, CLU secretion was inhibited and cCLU was accumulated, suggesting that cCLU might be pro‐survival, while in PC‐3 cells accumulation of nCLU was concomitant to caspase‐3 induction and PARP activation instead. Thus, CLU expression/sub‐cellular localization is strictly related to cell fate. In particular, nCLU and physiological levels of HSP70 affected cell survival in an antagonistic fashion. Prevalence of heat‐induced nCLU, not allowing PC‐3 cells to cope with heat shock, could be the rational explaining why malignant cells are more sensitive to heat when delivered by minimally invasive procedures for ablation of localized prostate cancer. J. Cell. Physiol. 207: 208–219, 2006. © 2005 Wiley‐Liss, Inc.
EGF blocks NADPH oxidase activation by TGF‐β in fetal rat hepatocytes, impairing oxidative stress, and cell death
Authors: Carmona‐Cuenca Irene , Herrera Blanca , Ventura Juan‐José , Roncero César , Fernández Margarita , Fabregat Isabel
Published: December 2005

Epidermal growth factor (EGF) is a survival signal for transforming growth factor‐beta (TGF‐β)‐induced apoptosis in hepatocytes, phosphatidylinositol 3‐kinase (PI 3‐K) being involved in this effect. Here, we analyze the possible cross talks between EGF and TGF‐β signals to understand how EGF impairs the early pro‐apoptotic events induced by TGF‐β. Data have indicated that neither SMAD nor c‐Jun NH2 Terminal Kinase (JNK) activations are altered by EGF, which clearly interferes with events directly related to the radical oxygen species (ROS) production, impairing oxidative stress, p38 MAP kinase activation, and cell death. Activation of a NADPH‐oxidase‐like system, which is responsible for the early ROS production by TGF‐β, is completely inhibited by EGF, through a PI 3‐K‐dependent mechanism. Activity of RAC1 increases by TGF‐β, but also by EGF, and both act synergistically to get maximum effects. Fetal rat hepatocytes express nox4, in addition to nox1 and nox2, and TGF‐β clearly upregulates nox4. EGF blocks up‐regulation of nox4 by TGF‐β. Interestingly, in the presence of PI 3‐K inhibitors, EGF is not able to counteract the nox4 upregulation by TGF‐β. Taking together these results indicate that impairment of TGF‐β‐induced NADPH oxidase activation by EGF is a RAC1‐independent process and correlates with an inhibition of the mechanisms that address the increase of nox4 mRNA levels by TGF‐β. J. Cell. Physiol. 207: 322–330, 2006. © 2005 Wiley‐Liss, Inc.
SEL1L a multifaceted protein playing a role in tumor progression
Authors: Biunno Ida , Cattaneo Monica , Orlandi Rosaria , Canton Cristina , Biagiotti Laura , Ferrero Stefano , Barberis Massimo , Pupa Serenella M. , Scarpa Aldo , Ménard Sylvie
Published: December 2005

Since the cloning in 1997 of SEL1L, the human ortholog of the sel‐1 gene of C. elegans, most studies have focused on its role in cancer progression and have provided significant evidences to link its increased expression to a decrease in tumor aggressiveness. SEL1L resides on a “Genome Desert area” on chromosome 14q24.3‐31 and is highly conserved in evolution. The function of the SEL1L encoded protein is still very elusive although, several evidences from lower organisms indicate that it plays a major role in protein degradation using the ubiquitin‐proteosome system. SEL1L has a very complex structure made up of modules: genomically it consists of 21 exons featuring several alternative transcripts encoding for putative protein isoforms. This structural complexity ensures protein flexibility and specificity, indeed the protein was found in different sub‐cellular compartments and may turn on a particular transcript in response to specific stimuli. The overall architecture of SEL1L guarantees an exquisite regulation in the expression of the gene. © 2005 Wiley‐Liss, Inc.
Involvement of Kv1.1 and Nav1.5 in proliferation of gastric epithelial cells
Authors: Wu William Ka Kei , Li Gui Rong , Wong Helen Pui Shan , Hui Marco King Cheung , Tai Emily Kin Ki , Lam Emily Kai Yee , Shin Vivian Yvonne , Ye Yi Ni , Li Peng , Yang Ying Hua , Luo Jiing Chyuan , Cho Chi Hin
Published: December 2005

In the present study, patch clamp experiments demonstrated the expression of multiple ionic currents, including a Ba2+‐sensitive inward rectifier K+ current (IKir), a 4‐aminopyridine‐ (4‐AP) sensitive delayed rectifier K+ current (IKDR), and a nifedipine‐sensitive, tetrodotoxin‐resistant inward Na+ current (INa.TTXR) in the non‐transformed rat gastric epithelial cell line RGM‐1. RT‐PCR revealed molecular identities of mRNAs for the functional ionic currents, including Kir1.2 for IKir, Kv1.1, Kv1.6, and Kv2.1 for IKDR, and Nav1.5 for INa.TTXR. Pharmacologic blockade of Kv and Nav, but not Kir, suppressed RGM‐1 cell proliferation. To further elucidate which subtypes of the ion channels were involved in cell proliferation, RNA interference was employed to knockdown specific gene expression. Downregulation of Kv1.1 or Nav1.5 by RNA interference suppressed RGM‐1 cell proliferation. To conclude, our study is the first to delineate the expression of ion channels and their functions as growth modulators in gastric epithelial cells. J. Cell. Physiol. 207: 437–444, 2006. © 2005 Wiley‐Liss, Inc.
Recording high quality speech during tagged cine‐MRI studies using a fiber optic microphone
Authors: NessAiver Moriel S. , Stone Maureen , Parthasarathy Vijay , Kahana Yuvi , Paritsky Alex
Published: December 2005

Purpose

To investigate the feasibility of obtaining high quality speech recordings during cine imaging of tongue movement using a fiber optic microphone.

Materials and Methods

A Complementary Spatial Modulation of Magnetization (C‐SPAMM) tagged cine sequence triggered by an electrocardiogram (ECG) simulator was used to image a volunteer while speaking the syllable pairs /a/‐/u/, /i/‐/u/, and the words “golly” and “Tamil” in sync with the imaging sequence. A noise‐canceling, optical microphone was fastened approximately 1–2 inches above the mouth of the volunteer. The microphone was attached via optical fiber to a laptop computer, where the speech was sampled at 44.1 kHz. A reference recording of gradient activity with no speech was subtracted from target recordings.

Results

Good quality speech was discernible above the background gradient sound using the fiber optic microphone without reference subtraction. The audio waveform of gradient activity was extremely stable and reproducible. Subtraction of the reference gradient recording further reduced gradient noise by roughly 21 dB, resulting in exceptionally high quality speech waveforms.

Conclusion

It is possible to obtain high quality speech recordings using an optical microphone even during exceptionally loud cine imaging sequences. This opens up the possibility of more elaborate MRI studies of speech including spectral analysis of the speech signal in all types of MRI. J. Magn. Reson. Imaging 2006. © 2005 Wiley‐Liss, Inc.
Glucocorticoids inhibit tenocyte proliferation and Tendon progenitor cell recruitment
Authors: Scutt Nanette , Rolf Christer G. , Scutt Andrew
Published: December 2005

Corticosteroid injection is commonly used to treat tendon injuries but is often associated with tendon rupture and impaired tendon healing. The effects of dexamethasone on tenocytes have been studied in vitro but only using high concentrations of dexamethasone in monolayer cultures of tenocytes over short periods of time. We have therefore investigated the effects of physiological and pharmacological concentrations of dexamethasone on monolayer cultures of tenocytes over extended time periods. We have also used fibroblastic‐colony forming unit cultures to examine the effects of dexamethasone on a progenitor cell population located in tendons. Culturing tenocytes in the presence of dexamethasone for a period of 24 days resulted in a concentration‐related decrease in cell number and collagen synthesis as compared to control cultures. This effect was time dependent with cell number in both dexamethasone‐treated and control cultures leveling off after 14 days with the control cultures reaching higher cell densities. In contrast in control cultures, collagen accumulation continued to increase until week 4, whereas in the presence of dexamethasone, this tended to level off after 14 days. To study the role of progenitor cell recruitment, the effects of dexamethasone were investigated using the fibroblastic‐colony forming unit assay. Treatment with dexamethasone at concentrations of 0.1 nM to 10 µM leads to a progressive reduction in mean colony size as compared to control cultures. Colony number remained constant at concentrations below 10 nM but fell progressively at concentrations above this. In conclusion, dexamethasone reduces both cell number and collagen synthesis in tenocyte cultures in a concentration‐dependent manner by both direct effects on tenocyte proliferation and collagen accumulation, and also by modulating the recruitment of tendon progenitor cells. © 2005 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Anatomy of the posterolateral aspect of the goat knee
Authors: LaPrade Robert F. , Kimber Kristofer A. , Wentorf Fred A. , Olson Erik J.
Published: December 2005

The purpose of this study was to determine the anatomy of the posterolateral aspect of the goat knee for future in vivo studies using a goat model to examine the natural history of posterolateral knee injuries. Twelve nonpaired, fresh‐frozen, adult goat knees were dissected to determine the anatomy of the posterolateral corner. The main posterolateral structures identified in the goat knee were the lateral collateral ligament, the popliteus muscle and tendon, popliteomeniscal fascicles, and the lateral gastrocnemius muscle. The lateral collateral ligament was extra‐articular and coursed from its proximal attachment, located posterior and proximal to the lateral epicondyle, to its distal attachment on the lateral aspect of the fused proximal tibiofibula. The popliteus muscle attached to the medial edge of the posterodistal tibia, traveled anterolaterally, became intra‐articular at its musculotendinous junction, and attached to the lateral femur just distal to the lateral epicondyle. Distinct popliteomeniscal fascicles attached the lateral meniscus to the popliteus muscle and tendon, and a fascial attachment from the musculotendinous junction of the popliteus muscle coursed to the lateral tibial plateau. This study provided information on the structures present in the posterolateral aspect of the goat knee and enhanced our understanding of their relationships to analogous structures in the human knee. This information is important to enable future development of potential models of the natural history of posterolateral knee injuries and also to test surgical techniques and the in vivo effects of these injuries on cruciate ligament reconstructions. © 2005 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Antimicrobial efficacy of gentamicin‐loaded acrylic bone cements with fusidic acid or clindamycin added
Authors: Neut Daniëlle , Hendriks Johannes G.E. , van Horn Jim R. , Kowalski Rick S.Z. , van der Mei Henny C. , Busscher Henk J.
Published: December 2005

The increasing gentamicin resistance among bacteria in septic joint arthroplasty has stimulated interest in adding a second antibiotic into gentamicin‐loaded bone cement. A first aim of this in vitro study is to investigate whether addition of fusidic acid or clindamycin to gentamicin‐loaded bone cement has an additional antimicrobial effect against a collection of 38 clinical isolates, including 16 gentamicin‐resistant strains. A modified Kirby‐Bauer test, involving measurement of the inhibition zone around antibiotic‐loaded bone cement discs on agar plates, was used to investigate whether adding a second antibiotic has an additional antimicrobial effect. Second, a selected number of strains was used to study their survival in an interfacial gap made in the different bone cements to mimic the gap between bone and cement as existing near a prosthesis. Gentamicin‐loaded bone cement had an antimicrobial activity against 58% of the 38 bacterial strains included in this study, while 68% of the strains were affected by bone cement loaded with a combination of gentamicin and clindamycin. Bone cement loaded with the combination of gentamicin and fusidic acid had antimicrobial activity against 87% of the bacterial strains. In the prosthesis‐related gap model, there was a clear trend toward less bacterial survival for gentamicin‐loaded bone cement after adding clindamycin or fusidic acid. Addition of clindamycin or fusidic acid into gentamicin‐loaded bone cement yields an additional antimicrobial effect. The combination gentamicin and fusidic acid was effective against a higher number of clinical isolates than the combination of gentamicin with clindamycin, including gentamicin‐resistant strains.©2005 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res