bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ethylene polymerization with porous polystyrene spheres supported Cp2ZrCl2 catalyst
Authors: Qin Yongxin , Tang Tao , Zhao Zhongfu , Huang Baotong 
Published: September 2003

AbstractA catalyst with porous polystyrene beads supported Cp2ZrCl2 was prepared and tested for ethylene polymerization with methylaluminoxane as a cocatalyst. By comparison, the porous supported catalyst maintained higher activity and produced polyethylene with better morphology than its corresponding solid supported catalyst. The differences between activities of the catalysts and morphologies of the products were reasonably explained by the fragmentation processes of support as frequently observed with the inorganic supported Ziegler–Natta catalysts. Investigation into the distribution of polystyrene in the polyethylene revealed the fact that the porous polystyrene supported catalyst had undergone fragmentation during polymerization. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3313–3319, 2003
Synthesis and chiral recognition ability of optically active poly{N‐[(R)‐α‐methoxycarbonylbenzyl]methacrylamide} with various tacticities by radical polymerization using Lewis acids
Authors: Morioka Kohei , Suito Yoshikatsu , Isobe Yutaka , Habaue Shigeki , Okamoto Yoshio 
Published: September 2003

AbstractThe radical polymerization of an optically active methacrylamide, N‐[(R)‐α‐methoxycarbonylbenzyl]methacrylamide, was carried out in the absence and presence of Lewis acids such as yittribium trifluoromethanesulfonate [Yb(OTf)3] and scandium trifluoromethanesulfonate [Sc(OTf)3]. Catalytic amounts of the Lewis acids significantly affected the stereoregularity of the obtained polymers. The polymerization with Yb(OTf)3 in tetrahydrofuran afforded isotactic polymers (up to mm = 87%), whereas the conventional radical method without the Lewis acid produced polymers rich in syndiotacticity (up to rr = 88%). The radical polymerization in the presence of MgBr2 proceeded in a heterotactic‐selective manner (mr = 63%). Thus, the isotactic, syndiotactic, and heterotactic poly(methacrylamide)s were synthesized by the radical processes. The chiral recognition abilities of the obtained optically active poly(methacrylamide)s were affected by the stereoregularity. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3354–3360, 2003
Synthesis of well‐defined macromonomers and comb copolymers from polymers made by atom transfer radical polymerization
Authors: Muehlebach Andreas , Rime François 
Published: September 2003

AbstractPoly(n‐butyl acrylate) macromonomers with predetermined molecular weights (1300 < number‐average molecular weight < 23,000) and low polydispersity indices (<1.2) were synthesized from bromine‐terminated atom transfer radical polymerization polymers via end‐group substitution with acrylic acid and methacrylic acid. These macromonomers, having a high degree of end‐group functionalization (>90%), were radically homopolymerized to obtain comb polymers. A high macromonomer concentration, combined with a low radical flux, was needed to obtain a high conversion of the macromonomers and a reasonable degree of polymerization. By the traditional radical copolymerization of the hydrophobic macromonomers with the hydrophilic monomer N,N‐dimethylaminoethyl methacrylate (DMAEMA), amphiphilic comb copolymers were obtained. The conversions of the macromonomers and comonomer were almost quantitative under optimized reaction conditions. The molecular weights were high (number‐average molecular weight ≈70,000), and the molecular weight distribution was broad (polydispersity index ≈ 3.5). Kinetic measurements showed simultaneous decreases in the macromonomer and DMAEMA concentrations, indicating a relatively homogeneous composition of the comb copolymers over the whole molecular weight range. This was supported by preparative size exclusion chromatography. The copolymerization of poly(n‐butyl acrylate) macromonomers with other hydrophilic monomers such as acrylic acid or N,N‐dimethylacrylamide gave comb copolymers with multimodal molecular weight distributions in size exclusion chromatography and extremely high apparent molecular weights. Dynamic light scattering showed a heterogeneous composition consisting of small (6–9 nm) and large (23–143 nm) particles, probably micelles or other type of aggregates. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3425–3439, 2003
Cationic photopolymerization of epoxynorbornane linseed oils: The effect of diluents
Authors: Zong Zhengang , Soucek Mark D. , Liu Yubiao , Hu Jun 
Published: September 2003

AbstractNew epoxynorbornane linseed oils (ENLOs) were prepared as a function of the norbornene content. The cationic photopolymerization of ENLOs was investigated with real‐time infrared spectroscopy and photo‐differential scanning calorimetry. The effects of reactive and nonreactive diluents on the polymerization rate were also studied. The diluents reduced the viscosity of the formulations, markedly accelerated the rate of polymerization of ENLOs, and increased their final conversions. The effects of the reactive diluent were compared for ENLOs and epoxidized linseed oil. The relative reactivity of the oxiranes was not as important as the viscosity of the reacting system, and it was proposed that the cationic photopolymerization of ENLOs was controlled by diffusion. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3440–3456, 2003
Pneumonia due to Chlamydia pneumoniae in children: Epidemiology, diagnosis, and treatment
Authors: Hammerschlag Margaret R. 
Published: September 2003

AbstractThe term “atypical” pneumonia has been used to differentiate infections caused by Chlamydia pneumoniae, Mycoplasma pneumoniae, Legionella, and other related organisms from pneumonia caused by classic bacteria, the prototype being Streptococcus pneumoniae. However, recent studies demonstrated that the clinical presentation of pneumonia due to atypical pathogens cannot readily be differentiated from those caused by “typical” bacteria. This is further complicated by the observation that coinfections with atypical pathogens and other bacteria are frequent. Nonetheless, the term “atypical” can be useful, as these organisms share a number of characteristics that separate them from “typical” bacteria. They are either obligate or facultative intracellular parasites that cannot be isolated using routine microbiologic methods. The most commonly used method of diagnosis of these infections is serology, which has significant limitations. Although C. pneumoniae is now recognized worldwide as a common cause of respiratory infections in adults and children, major gaps remain in our knowledge of the biology of this organism and how it causes disease, in major part due to the lack of readily available, standardized diagnostic methods. Pediatr Pulmonol. 2003; 36:384–390. © 2003 Wiley‐Liss, Inc.
Pediatric lymphocytic interstitial pneumonitis in an HIV‐negative child with pulmonary Epstein‐Barr virus infection
Authors: Mueller Gary A. , Pickoff Arthur S. 
Published: September 2003

AbstractLymphocytic interstitial pneumonitis (LIP) in children has been most commonly associated with human immunodeficiency virus (HIV) infection. Epstein‐Barr virus (EBV) associated LIP without HIV infection has been reported only in adults. EBV associated LIP has been reported in children, but only with concurrent HIV infection. We report a case of EBV associated, HIV negative LIP in a child. Pediatr Pulmonol. 2003; 36:447–449. © 2003 Wiley‐Liss, Inc.
Exhaled nitric oxide and tracheal endothelin‐1 in preterm infants with and without RDS
Authors: Olsen Steven L. , Clark Perry L. , Thibeault Donald W. , Norberg Mike , Truog William E. 
Published: September 2003

AbstractWe measured exhaled nitric oxide and tracheal aspirate endothelin‐1 to determine relationships between these substances and alterations in pulmonary gas exchange during respiratory distress syndrome (RDS) in comparison to those obtained from control preterm infants without RDS. Eight infants with RDS had measurements made at 24 hr and again at 48–72 hr. Eight control infants were studied once at 24–48 hr of life. Exhaled gas was analyzed on‐line, and minute excretion of NO (V̇NO) was calculated. ET‐1 was determined by immunoassay. Median V̇NO at 24 hr in RDS was 0.405 nl/min/kg (range, 0.30 –0.79), which subsequently declined by 48–72 hr to 0.166 nl/min/kg (P < 0.01). The V̇NO in RDS infants was significantly higher than time‐matched V̇NO in controls, with a median of 0.099 nl/min/kg (range, 0.03–0.27; P < 0.001). ET‐1 was not correlated with initial V̇NO in the RDS or control patients. In conclusion, in RDS, V̇NO decreases as gas exchange improves. ET‐1 is detectable in tracheal aspirate samples in both groups of infants. Pediatr Pulmonol. 2003; 36:421–426. © 2003 Wiley‐Liss, Inc.
Pseudomonas aeruginosa and cystic fibrosis: Correlation between exoenzyme production and patient's clinical state
Authors: Lanotte P. , Mereghetti L. , Lejeune B. , Massicot P. , Quentin R. 
Published: September 2003

AbstractIn this study, we investigated the correlation between the production by Pseudomonas aeruginosa isolates of four exoenzymes (protease, elastase, neuraminidase, and phospholipase C (PLC)) and the clinical state of cystic fibrosis (CF) patients. We studied 212 P. aeruginosa isolates from 22 CF patients chronically infected with this bacterium. Patients were classified into three clinical groups according to a modified Shwachman‐Kulczycki‐Khaw (SKK) scoring system. The production of enzymes by isolates from patients in the three populations was analyzed and compared using four statistical tests: chi‐square, Mann‐Whitney U, principal component analysis, and discriminant analysis. Isolates from patients with excellent or good clinical status (group I, SKK score ≥71) had higher elastase and neuraminidase activities than isolates from the other patients. In contrast, PLC activity, a common characteristic of CF isolates, was higher in isolates from patients with poor or weak clinical status (group III, SKK score ≤55). PLC also appeared to be the best parameter for differentiating between groups I and III. Enzyme production was highly variable in group II isolates (SKK score, 56–70). Our results suggest that P. aeruginosa isolates from patients with good clinical status produce large amounts of neuraminidase, and that PLC production may be involved in the decrease in pulmonary function. Pediatr Pulmonol. 2003; 36:405–412. © 2003 Wiley‐Liss, Inc.
Effect of long‐acting β2 agonists on exacerbation rates of asthma in children
Authors: Bisgaard Hans 
Published: September 2003

AbstractThe purpose of this analysis was to examine the effect of long‐acting β2‐adrenoceptor agonists (LABAs) on the asthma exacerbation rate in pediatric patients. Randomized controlled trials (RCT) that included the use of LABAs to treat symptoms of pediatric asthma in children on inhaled corticosteroids, that reported asthma exacerbation rates, and that were published as full papers in peer‐reviewed journals were retrieved from a search of the medical literature. Eight studies were identified that fulfilled these criteria. An exacerbation was defined as deterioration in a patient's asthma requiring a change in prescribed medication or not defined but reported as an asthma exacerbation or an asthma‐related hospitalization. Analysis of data from the eight studies revealed no apparent protection from an asthma exacerbation among children on a LABA compared to patients on comparator treatment. The relative risk of an asthma exacerbation for LABA compared to placebo or short‐acting β2‐adrenoceptor agonist (SABA) ranged from 0.95–1.86. The relative risk of hospitalization for asthma in patients treated with LABAs with regular maintenance with ICS ranged from 3.3–21.6 in the three studies that reported asthma‐related hospitalizations. The lack of evidence for the control of asthma exacerbations in children regularly using a LABA should bring into question its general use as add‐on therapy. Studies should be designed to directly explore the implications of these observations in pediatric patients. Pediatr Pulmonol. 2003; 36:391–398. © 2003 Wiley‐Liss, Inc.
Epidemic spread of Pandoraea apista, a new pathogen causing severe lung disease in cystic fibrosis patients
Authors: Jørgensen Inger Merete , Johansen Helle Krogh , Frederiksen Birgitte , Pressler Tacjana , Hansen Annelise , Vandamme Peter , Høiby Niels , Koch Christian 
Published: September 2003

AbstractWe show that Pandoraea apista must be added to the increasing list of pathogens capable of causing chronic lung infection in cystic fibrosis (CF) patients. It is most likely that this strain of P. apista was transmissible among patients with CF, leading to spread of infection from the index patient to 5 other patients exposed during participation in winter camps and/or hospitalization. All patients developed chronic infection with high levels of antibodies, and 4 patients had a downhill course of lung disease. P. apista must therefore be considered a new and sometimes important pathogen for CF patients. Cohort isolation prevented further spread of P. apista in our CF center. Pediatr Pulmonol. 2003; 36:439–446. © 2003 Wiley‐Liss, Inc
Molecular characterization of human prostate carcinoma cell lines
Authors: van Bokhoven Adrie , Varella‐Garcia Marileila , Korch Christopher , Johannes Widya U. , Smith E. Erin , Miller Heidi L. , Nordeen Steven K. , Miller Gary J. , Lucia M. Scott 
Published: September 2003

AbstractBACKGROUNDThis study presents a comprehensive survey and characterization of available prostate carcinoma cell lines, most of which have been widely used but are incompletely characterized.METHODSA total of 21 cell lines were investigated, including three “classical” (DU 145, LNCaP, and PC‐3) and 18 “non‐classical” lines (1013L, 22Rv1, ALVA‐55, ALVA‐101, ARCaP, CWR‐R1, DuCaP, DuPro‐1, LAPC‐4, MDA PCa 1, MDA PCa 2a, MDA PCa 2b, NCI‐H660, PC‐346C, PC‐93, PSK‐1, UM‐SCP‐1, and VCaP). Cytogenetics, DNA profiling, expression of basal, luminal, and neuroendocrine differentiation markers, and mutation analyses of the TP53 and androgen receptor (AR) genes were performed.RESULTSBased on cytogenetics and DNA profiling analyses, out of the 18 “non‐classical” lines, six were confirmed to be unique, eight (in four pairs) were confirmed to be related in origin, and four lines were identified as cross‐contaminants. Of this latter group, PC‐93 was found to be a derivative of HeLa, whereas DuPro‐1, ALVA‐55, and ALVA‐101 were derivatives of PC‐3. The 17 genuine prostate cell lines expressed keratin 8 (K8) and K18. Nine showed AR expression, of which five harbored mutations in the AR gene. Prostate‐specific antigen and DD3 were exclusively detected in AR expressing cell lines. Seven lines expressed the basal cell marker K5, three of these lines showed co‐expression of AR.CONCLUSIONSThis study defines a collection of 17 genuine prostate carcinoma cell lines. This collection, although small, constitutes a variety of different types and stages of prostate cancer, while it also partly reflects the heterogeneous nature of this malignancy. Prostate 57: 205–225, 2003. © 2003 Wiley‐Liss, Inc.
Spectral karyotype (SKY) analysis of human prostate carcinoma cell lines
Authors: van Bokhoven Adrie , Caires Aimee , Maria Michael Di , Schulte Aline Passarini , Lucia M. Scott , Nordeen Steven K. , Miller Gary J. , Varella‐Garcia Marileila 
Published: September 2003

AbstractBACKGROUNDWell‐characterized in vitro model systems provide an invaluable tool for studying prostate cancer in the laboratory. Detailed karyotypes have been reported using modern techniques such as multiplex fluorescence in situ hybridization (M‐FISH) and spectral karyotyping (SKY) for LNCaP, DU 145, NCI‐H660, and PC‐3 cell lines. However, karyotypic data for more recently established prostate carcinoma cell lines are still limited.METHODSClassical (G‐banding) and SKY analyses were performed on ten prostate carcinoma cell lines: 22Rv1, CWR‐R1, DuCaP, LAPC‐4, MDA PCa 1, MDA PCa 2a, MDA PCa 2b, PC‐346C, PSK‐1, and VCaP.RESULTSChromosomal abnormalities were identified in all cell lines, although the number and complexity varied greatly among them. PC‐346C, established from a primary tumor, exhibited the lowest number (3) of clonal structural abnormalities, while DuCaP, established from a metastasis from a hormone‐refractory patient, exhibited both the highest number (31) and largest complexity of structural abnormalities. In various subsets of these models, breakpoints were identified in chromosomal regions previously described as being involved in prostate cancer (e.g., 8p, 10q, 13q, and 16q).CONCLUSIONSThe present study provides a comprehensive karyotypic analysis of a large number of prostate carcinoma cell lines, and offers a valuable resource for future investigations. Prostate 57: 226–244, 2003. © 2003 Wiley‐Liss, Inc.
Transactivation of epidermal growth factor receptor after heparin‐binding epidermal growth factor‐like growth factor shedding in the migration of prostate cancer cells promoted by bombesin
Authors: Madarame Jun , Higashiyama Shigeki , Kiyota Hiroshi , Madachi Ayako , Toki Fujio , Shimomura Tatsuya , Tani Naoyuki , Oishi Yukihiko , Matsuura Nariaki 
Published: September 2003

AbstractBACKGROUNDA pathway consisting of bombesin, G‐protein coupling receptors (GPCRs), metalloproteases, pro‐heparin‐binding epidermal growth factor (proHB‐EGF), and epidermal growth factor receptor (EGFR) has been reported in prostate cancer cells. The occurrence of HB‐EGF shedding from proHB‐EGF in this pathway, however, has not been proven directly. In addition, it is still unclear how much this pathway contributes to the migration of prostate cancer cells. In this study, we tried to directly elucidate HB‐EGF shedding in this pathway and to determine its contribution to the migration of prostate cancer cells.METHODSRT‐PCR and indirect immunofluorescence staining for HB‐EGF and its receptors, such as EGFR and HER4/erbB4, were performed on PC‐3 cells. The influences of bombesin, anti‐EGFR neutralizing monoclonal antibody, HB‐EGF, and HB‐EGF shedding inhibitor on the migration of PC‐3 cells were studied by means of in vitro wound assays. The amount of HB‐EGF shed from PC‐3 cells with alkaline phosphatase‐tagged HB‐EGF in the presence of bombesin was determined by measuring AP activity. Immunoprecipitations and phosphotyrosine Western blotting were performed to detect EGFR transactivated by bombesin.RESULTSPC‐3 expressed HB‐EGF and EGFR, but not HER4/erbB4. PC‐3 migrated in the presence of bombesin, but its migration was partly inhibited by the neutralizing antibody against EGFR. PC‐3 also migrated in the presence of HB‐EGF, but HB‐EGF shedding inhibitor partly inhibited this phenomenon. HB‐EGF was shed from PC‐3 cells in the presence of bombesin, and this shedding was inhibited by HB‐EGF shedding inhibitor. In addition, the EGFR on PC‐3 was activated in the presence of bombesin and inactivated in the presence of HB‐EGF shedding inhibitor.CONCLUSIONSThese results indicated that HB‐EGF shedding and the following transactivation of EGFR occurs in this pathway and that this pathway partly contributes to the migration of prostate cancer cells. Prostate 57: 187–195, 2003. © 2003 Wiley‐Liss, Inc.
Expression of protein C inhibitor (PCI) in benign and malignant prostatic tissues
Authors: Cao Yue , Becker Charlotte , Lundwall Åke , Christensson Anders , Gadaleanu Virgil , Lilja Hans , Bjartell Anders 
Published: September 2003

AbstractBACKGROUNDProtein C inhibitor (PCI) occurs at high concentration in seminal plasma, and inhibits human glandular kallikrein‐2 and, less readily, prostate‐specific antigen. Previous studies have localized PCI in the male genital tract. Here we have performed a detailed investigation of PCI expression in the prostatic tissues, metastases, and cell lines.METHODSImmunohistochemistry, in situ hybridization, and Western blotting were used to study prostatic tissues, metastases, and PC‐3, DU‐145, and LNCaP cells.RESULTSPCI was immunolocalized in tissue microarray spots with BPH epithelium (detection rate 100%), PIN lesions (100%), tumors (96%), metastases (88%), and in all cell lines. ISH and WB supported the findings.CONCLUSIONSPCI is widely expressed in benign prostatic epithelium, and may act as a local regulator of enzymatic activity in seminal fluid, of importance for normal sperm function. Lack of PCI expression in a subpopulation of high‐grade tumor cells in combination with maintained protease expression may facilitate invasive growth patterns. Prostate 57: 196–204, 2003. © 2003 Wiley‐Liss, Inc.
Increased fatty acid synthase expression and activity during progression of prostate cancer in the TRAMP model
Authors: Pflug Beth R. , Pecher Stefana M. , Brink Alisa W. , Nelson Joel B. , Foster Barbara A. 
Published: September 2003

AbstractBACKGROUNDFatty acid synthase (FAS) is the major enzyme required to convert carbohydrates to fatty acids. Recent evidence suggests that FAS activity is essential for prostate cancer growth and survival, since blocking the enzyme activity results in cell death. In this study, the role of FAS up‐regulation during prostate tumor progression in the transgenic adenocarcinoma of mouse prostate (TRAMP) model was investigated. Sensitivity to FAS anti‐metabolites was also analyzed in TRAMP prostate tumor cells and tissue to determine therapeutic potential of FAS inhibition in the treatment of prostate cancer.METHODSFAS expression was evaluated by immunohistochemistry of TRAMP tissues, including primary and metastatic lesions in mice of varying ages. FAS pathway activity was studied in vitro using TRAMP‐derived cell lines and in vivo in TRAMP tissues. The sensitivity of TRAMP cell lines and tissues to the antimetabolite drugs (2R,3S)‐2,3‐epoxy‐4‐oxo‐7,10‐trans, transdodecadienamide (cerulenin) and C‐75, which target FAS, was determined by FAS antimetabolite inhibition of 14C‐acetate conversion to fatty acids, cell growth inhibition, and apoptosis analyses.RESULTSHigh FAS expression and activity in the TRAMP mouse prostate was evident at 12 weeks of age compared with nontransgenic littermates and further increased with age, tumor progression, and in metastatic lesions. FAS pathway inhibition resulted in a dose‐dependent reduction in cell survival and decreased enzyme activity in these models.CONCLUSIONSThese data suggest that the up‐regulation of FAS expression play a role in tumorigenesis of the prostate in the TRAMP model and hence can provide valuable insight into human prostate cancer. Given the response of tumor cells to FAS antimetabolites, FAS may serve as a novel target for prostate cancer therapy. Prostate 57: 245–254, 2003. © 2003 Wiley‐Liss, Inc.