bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phage display selection of peptides that affect prostate carcinoma cells attachment and invasion
Authors: Romanov Victor I. , Durand David B. , Petrenko Valery A. 
Published: October 2004

AbstractBACKGROUNDProstate cancer‐specific proteins must be identified to serve as diagnostic and prognostic markers. Cell surface proteins are especially important, because they have potential utility as diagnostic markers and therapeutic targets. Identification of ligands for these proteins will allow use of these ligands as diagnostic and therapeutic tools and permit the investigation of receptor function. We performed a search for peptide ligands to prostate cancer cell‐specific receptors.METHODSPeptide phage display library was used to isolate specific ligands to LNCaP prostate carcinoma cells receptors. Selected phage and cognate peptides were investigated for their cancer‐related functions, such as the ability to interfere with cell adhesion, spreading, motility, and invasion.RESULTSPhage designated pg35, blocked spreading of LNCaP cells and their derivatives C4–2 and C4–2b. Cognate peptide did not inhibit spreading, but incubation of C4–2 and C4–2b cells with cognate peptide increased their affinity for endothelial cells and invasiveness. In addition, the peptide activates matrix metalloproteinase (MMP)‐2 and 9 in C4–2 and C4–2b cells.CONCLUSIONSThese results indicate that identified ligands may play a role in tumorigenicity and metastatic transformation of prostate cancer. To our knowledge, this is the first identification of a functional cancer‐specific peptide ligand using the phage display approach. Prostate 47:239–251, 2001. © 2001 Wiley‐Liss, Inc.
Tumor characteristics in screening for prostate cancer with and without rectal examination as an initial screening test at low PSA (0.0–3.9 ng/ml)
Authors: Vis André N. , Hoedemaeker Robert F. , Roobol Monique , van der Kwast Theo H. , Schröder Fritz H. 
Published: October 2004

AbstractBACKGROUNDThe value of rectal examination as initial screening test for prostate cancer at low PSA values (0.0–3.9 ng/ml) was determined by evaluating the number and tumor characteristics of the cancers detected.METHODSTwo study populations were subjected to screening with (n = 10,226) and without (n = 10,753) rectal examination as initial screening test. The number of cancers detected at low PSA values for both screening regimens, the corresponding biopsy and radical prostatectomy tumor characteristics were assessed. Possibly harmless cancers were defined as small (< 0.5 ml) organ‐confined tumors without Gleason growth‐patterns 4/5.RESULTSAt low PSA, 26.6% (117/440) of screen‐detected cancers were detected after the evaluation of a suspicious rectal examination. The number of cancers and tumor aggressiveness features were highly associated with serum‐PSA level. The proportion of possibly harmless disease steadily declined from 100% (PSA 0.0–0.9 ng/ml) to 15.4% (PSA 3.0–3.9 ng/ml). Rectal examinations were performed unnecessarily in 94.7–100% of cases, when detection of clinically significant disease was aimed at. Using PSA (and a cut‐off of 3.0 ng/ml) as the only screening tool, 24.3% (121/498) of screen‐detected cancers were in the PSA range 3.0–3.9 ng/ml, and 60.0% were assessed as clinically significant.CONCLUSIONSRectal examination as initial screening test for prostate cancer at low PSA values may be replaced by screening using serum‐PSA only. At PSA levels below 3.0 ng/ml, 289 rectal examinations are required to find one case of clinically significant disease, and 96 rectal examinations are needed to diagnose prostate cancer of any size, grade, or stage. Prostate 47:252–261, 2001. © 2001 Wiley‐Liss, Inc.
The association of fatty acids with prostate cancer risk
Authors: Newcomer Laura M. , King Irena B. , Wicklund Kristine G. , Stanford Janet L. 
Published: October 2004

AbstractBACKGROUNDAnimal studies indicate that omega‐6 fatty acids promote and omega‐3 fatty acids inhibit tumor development. This pilot study was designed to evaluate whether these fatty acids are associated with human prostate cancer.METHODSLevels of erythrocyte membrane omega‐3 and omega‐6 fatty acids were determined for 67 incident prostate cancer cases and 156 population‐based controls.RESULTSProstate cancer risk was increased in the highest compared to the lowest quartile of α‐linolenic acid (OR = 2.6, 95% CI = 1.1–5.8, trend P = 0.01). Positive associations were also observed with higher levels of linoleic acid (OR = 2.1, 95% CI = 0.9–4.8) and total omega‐6 fatty acids (OR = 2.3, 95% CI = 1.0–5.4).CONCLUSIONSResults are consistent with other studies showing that linoleic and total omega‐6 fatty acids increase risk of prostate cancer. Contrary to animal studies, α‐linolenic acid was also positively associated with risk. Further research will be required to clarify the role of these fatty acids in human prostate cancer. Prostate 47:262–268, 2001. © 2001 Wiley‐Liss, Inc.
Reduced expression of hMSH2 and hMLH1 and risk of prostate cancer: A case‐control study
Authors: Strom Sara S. , Spitz Margaret R. , Yamamura Yuko , Babaian Richard J. , Scardino Peter T. , Wei Qingyi 
Published: October 2004

AbstractBACKGROUNDAlthough prostate cancer is the most common incident cancer in men, not much is known about its etiology. We tested the hypothesis that expression levels of hMSH2 and hMLH1 in unaffected (normal) tissue play a role in the etiology of prostate cancer.METHODSTotal RNA was extracted from peripheral blood lymphocytes of subjects ascertained by a case‐control study (70 patients and 97 age‐ and ethnicity‐matched controls). A multiplex reverse transcription‐polymerase chain reaction assay was used to simultaneously evaluate the relative expression of hMSH2 and hMLH1, using β‐actin as the internal control.RESULTSThe relative gene expression levels of hMSH2 and hMLH1 were significantly lower in cases than in controls (P < 0.05 for both genes). When compared with the highest tertile of the controls, low expression levels (the middle and lowest tertiles) of hMLH1 were associated with significantly increased risk of prostate cancer in a dose–response relationship (ORs = 2.68, and 4.31; 95% confidence interval = 1.00–7.23 and 1.64–11.30, respectively) after adjustment for age, ethnicity, smoking status, and family history of prostate cancer.CONCLUSIONSThese results suggest that reduced expression of hMLH1 in peripheral lymphocytes may be a risk factor for prostate cancer. However, it cannot be ruled out that the reduced expression we observed may be caused by the disease status. Our findings and the factors that may affect the expression of hMLH1 need further confirmation in larger prospective studies. Prostate 47:269–275, 2001. © 2001 Wiley‐Liss, Inc.
Gonadotropin‐releasing hormone receptor expression in the human prostate
Authors: Tieva Åse , Stattin Pär , Wikström Pernilla , Bergh Anders , Damber Jan‐Erik 
Published: October 2004

AbstractBACKGROUNDInhibitory effects of gonadotropin‐releasing hormone (GnRH) analogs on prostate cancer cell proliferation, both in vivo and in vitro, indicate the presence of specific binding sites for GnRH on prostate cancer cells. To investigate this issue further, we examined the expression of GnRH receptor (GnRH‐R) mRNA and protein in human prostate biopsies as well as in other extrapituitary tissues.METHODSThe relative quantity of GnRH‐R mRNA was determined by reverse transcriptase–polymerase chain reaction (RT‐PCR) and immunohistochemistry (IHC) in human prostate biopsies. Extrapituitary GnRH‐R levels were determined by a semiquantitative PCR reaction.RESULTSUsing PCR, a relatively high expression level of GnRH‐R mRNA was found in prostate tumor tissue followed by normal prostate, thymus, and kidney expression levels. The levels showed by heart, brain, placenta, lung, liver, skeletal muscle, pancreas, colon, ovary, small intestine, spleen, and testis were low but detectable, whereas peripheral blood leukocyte showed no demonstrable product. GnRH‐R immunoreactivity was localized in both luminal and basal epithelial cells in benign and malignant prostate tissue, and GnRH‐R were also observed in intraprostatic lymphocytes. The relative GnRH‐R mRNA levels in prostate biopsies from 16 patients showed a wide range of individual differences, but these differences were not related to histological grade. Castration therapy did not significantly influence GnRH‐R mRNA expression in normal and malignant prostate tissue.CONCLUSIONSThese results suggest that epithelial cells and infiltrating lymphocytes are targets for GnRH action in the human prostate. Comparative data show relatively high GnRH‐R expression in human prostate tissue compared to other human tissues. Prostate 47:276–284, 2001. © 2001 Wiley‐Liss, Inc.
Therapeutic potential of curcumin in human prostate cancer. III. Curcumin inhibits proliferation, induces apoptosis, and inhibits angiogenesis of LNCaP prostate cancer cells in vivo
Authors: Dorai Thambi , Cao Yi‐Chen , Dorai Bhuvaneswari , Buttyan Ralph , Katz Aaron E. 
Published: October 2004

AbstractBACKGROUNDEarlier work from our laboratory highlighted the therapeutic potential of curcumin (turmeric), used as a dietary ingredient and as a natural anti‐inflammatory agent in India and other Southeast Asian countries. This agent was shown to decrease the proliferative potential and induce the apoptosis potential of both androgen‐dependent and androgen‐independent prostate cancer cells in vitro, largely by modulating the apoptosis suppressor proteins and by interfering with the growth factor receptor signaling pathways as exemplified by the EGF‐receptor. To extend these observations made in vitro and to study the efficacy of this potential anti‐cancer agent in vivo, the growth of LNCaP cells as heterotopically implanted tumors in nude mice was followed.METHODSThe androgen‐dependent LNCaP prostate cancer cells were grown, mixed with Matrigel and injected subcutaneously into nude mice. Experimental group received a synthetic diet containing 2% curcumin for up to 6 weeks. At the end point, sections taken from the excised tumors were evaluated for pathology, cell proliferation, apoptosis, and vascularity.RESULTSCurcumin causes a marked decrease in the extent of cell proliferation as measured by the BrdU incorporation assay and a significant increase in the extent of apoptosis as measured by an in situ cell death assay. Moreover, a significant decrease in the microvessel density as measured by the CD31 antigen staining was also seen.CONCLUSIONSCurcumin could be a potentially therapeutic anti‐cancer agent, as it significantly inhibits prostate cancer growth, as exemplified by LNCaP in vivo, and has the potential to prevent the progression of this cancer to its hormone refractory state. Prostate 47:293–303, 2001. © 2001 Wiley‐Liss, Inc.
Concentration of enzymatically active prostate‐specific antigen (PSA) in the extracellular fluid of primary human prostate cancers and human prostate cancer xenograft models
Authors: Denmeade Samuel R. , Sokoll Lori J. , Chan Daniel W. , Khan Saeed R. , Isaacs John T. 
Published: October 2004

AbstractBACKGROUNDProstate‐specific antigen (PSA) targeted prodrugs are under development in our laboratory. Concentrations of total PSA and enzymatically active PSA produced by various human prostate cancer xenograft models have not been well characterized.METHODSThe concentration of PSA secreted into the extracellular fluid (ECF) in normal human prostate tissue, primary prostate cancers obtained directly from patients, and serially passageable human prostate cancer xenografts (PC‐82, LNCaP, LAPC‐4) were determined using Tandem assays. Percent enzymatically active PSA in the ECF and in conditioned media was also determined using a previously validated assay employing a monoclonal antibody to the PSA catalytic site. In addition, the concentration and activity of PSA within sera from men with and without prostate cancer, as well as from tumor‐bearing animals, was likewise assayed.RESULTSNormal human prostate tissue and primary human prostate cancers have high concentrations of PSA in the ECF (i.e., 1600–2100 nM). The majority of this PSA is enzymatically active (i.e., 80–90%). Human PC‐82 prostate cancer xenografts also have high concentrations of PSA in the ECF (624 ± 360 nM), and the majority of this PSA is also enzymatically active (i.e., 66 ± 4%). In contrast, much lower concentrations of PSA are found in the ECF from LNCaP (45 ± 9 nM) and LAPC‐4 (7.3 ± 0.6 nM). Only a small portion of the total PSA isolated from DHT‐containing, serum‐free, conditioned media from these cell lines is enzymatically active (i.e., ∼18%). While PSA was detected in all serum samples regardless of the type of host, no enzymatically active PSA was detected in any of these serum samples.CONCLUSIONSProstate cancers obtained directly from patients produce and secrete large amounts of PSA, the majority of which is highly enzymatically active. In contrast, while PSA was detected in the sera, none of this PSA was enzymatically active. This is also the case for the human PC‐82 prostate cancer xenografts. In contrast, LNCaP and LAPC‐4 human prostate cancer xenograft models secrete ∼70–300‐fold less PSA in the ECF than prostate cancers from patients and the majority of this PSA is enzymatically inactive. Also, the serum from these animals had detectable PSA, but none of this PSA was enzymatically active. Thus, these latter two prostate cancer models define the least and the PC‐82, the most, optimized xenograft model for screening PSA targeted prodrugs. Prostate 48:1–6, 2001. © 2001 Wiley‐Liss, Inc.
Charge centers and formation of the protein folding core
Authors: Torshin Ivan Y. , Harrison Robert W. 
Published: October 2004

AbstractElectrostatic interactions are important for protein folding. At low resolution, the electrostatic field of the whole molecule can be described in terms of charge center(s). To study electrostatic effects, the centers of positive and negative charge were calculated for 20 small proteins of known structure, for which hydrogen exchange cores had been determined experimentally. Two observations seem to be important. First, in all 20 proteins studied 30–100% of the residues forming hydrogen exchange core(s) were clustered around the charge centers. Moreover, in each protein more than half of the core sequences are located near the centers of charge. Second, the general architecture of all‐α proteins from the set seems to be stabilized by interactions of residues surrounding the charge centers. In most of the α‐β proteins, either or both of the centers are located near a pair of consecutive strands, and this is even more characteristic for α/B and all‐β structures. Consecutive strands are very probable sites of early folding events. These two points lead to the conclusion that charge centers, defined solely from the structure of the folded protein may indicate the location of a protein's hydrogen exchange/folding core. In addition, almost all the proteins contain well‐conserved continuous hydrophobic sequences of three or more residues located in the vicinity of the charge centers. These hydrophobic sequences may be primary nucleation sites for protein folding. The results suggest the following scheme for the order of events in folding: local hydrophobic nucleation, electrostatic collapse of the core, global hydrophobic collapse, and slow annealing to the native state. This analysis emphasizes the importance of treating electrostatics during protein‐folding simulations. Proteins 2001;43:353–364. © 2001 Wiley‐Liss, Inc.
Adaptive robust stabilization of dynamic nonholonomic chained systems
Authors: Ge S. S. , Wang J. , Lee T. H. , Zhou G. Y. 
Published: October 2004

AbstractIn this article, the stabilization problem is investigated for dynamic nonholonomic systems with unknown inertia parameters and disturbances. First, to facilitate control system design, the nonholonomic kinematic subsystem is transformed into a skew‐symmetric form and the properties of the overall systems are discussed. Then, a robust adaptive controller is presented in which adaptive control techniques are used to compensate for the parametric uncertainties and sliding mode control is used to suppress the bounded disturbances. The controller guarantees the outputs of the dynamic subsystem (the inputs to the kinematic subsystem) to track some bounded auxiliary signals which subsequently drive the kinematic subsystem to the origin. In addition, it can also be shown all the signals in the closed loop are bounded. Simulation studies on the control of a unicycle wheeled mobile robot are used to show the effectiveness of the proposed scheme. © 2001 John Wiley & Sons, Inc.
Virtual passive control of flexible arms with collocated and noncollocated feedback
Authors: Wu Shang‐Teh 
Published: October 2004

AbstractA novel approach to the control of flexible manipulators is proposed. The controller includes both joint‐variable and tip‐deflection feedback. It is shown that tip‐deflection feedback transforms the original structure into new system in which the structure parameters are virtually scaled up or down. The new system can hence be easily stabilized via a strictly passive feedback law. A co‐hub, lumped‐parameter structure with multiple massless links is first investigated and stability conditions are developed. The results are then applied to a distributed‐parameter flexible arm, which is decomposed into an equivalent lumped‐parameter structure via a set of modal functions normalized in a particular way. Tip‐deflection feedback is shown to be capable of enhancing control performance on a flexible arm, and stability is ensured as long as the gain associated with the noncollocated feedback satisfies a simple inequality. The stability criteria re valid independent of high‐order flexible modes. © 2001 John Wiley & Sons, Inc.
Dynamic modeling, stability, and energy efficiency of a quadrupedal walking machine
Authors: Lin Ben Sheng , Song Shin‐Min 
Published: October 2004

AbstractIn the past, the dynamics of walking machines was studied based on very simple or simplified leg structures. A more complete dynamic model is essential for the further development of a practical walking machine. In this paper, the dynamic model of a realistic quadrupedal walking machine is derived for simulation and real‐time control purposes. The walker has four cylindrical pantograph legs, and the whole system consists of twenty‐nine links. The walking gait is wave gait with at least three feet on the ground at any time. Significant efforts have been made to improve the computational efficiency of the inverse dynamics, and the required CPU time is less than 10 ms on an IBM 3090. The derived dynamic model is then applied to study two practical issues of walking: dynamic stability and mechanical efficiency of different legs and gaits. Simulation results show clear advantages of one leg type over another, and of some walking strategies in terms of adjusting velocities, strokes, and duty factors for greater efficiency. © 2001 John Wiley & Sons, Inc.
Fibonacci solitaire
Authors: Gnedin Alexander , Kerov Sergei 
Published: October 2004

AbstractFibonacci Solitaire is a combinatorial algorithm which associates with a permutation of [n]={1,…,n} a partition of [n] into couples and singletons. We study the output configuration when the algorithm is applied to a random permutation, with emphasis on the large n‐asymptotics. We show that the set of singletons, properly scaled, resembles a familiar ‘stick‐breaking’ Poisson configuration, whereas the configuration of couples becomes close to uniform. © 2002 John Wiley & Sons, Inc. Random Struct. Alg., 20, 71–88, 2002
Two‐coloring random hypergraphs
Authors: Achlioptas Dimitris , Han kim Jeong , Krivelevich Michael , Tetali Prasad 
Published: October 2004

AbstractA 2‐coloring of a hypergraph is a mapping from its vertex set to a set of two colors such that no edge is monochromatic. Let H=H(k, n, p) be a random k‐uniform hypergraph on a vertex set V of cardinality n, where each k‐subset of V is an edge of H with probability p, independently of all other k‐subsets. Let \documentclass{article}\pagestyle{empty}\begin{document}$ m = p{{n}\choose{k}}$\end{document} denote the expected number of edges in H. Let us say that a sequence of events ℰn holds with high probability (w.h.p.) if limn→∞Pr[ℰn]=1. It is easy to show that if m=c2kn then w.h.p H is not 2‐colorable for c>ln 2/2. We prove that there exists a constant c>0 such that if m=(c2k/k)n, then w.h.p H is 2‐colorable. © 2002 Wiley Periodicals, Inc. Random Struct. Alg. 20: 249–259, 2002
Right order spectral gap estimates for generating sets of ℤ4
Authors: Löwe Matthias , Meise Christian 
Published: October 2004

AbstractUsing coupling arguments, a distance method and Zeifman's method we give sharp estimates on the spectral gap for a special case of the class of Markov chains on generating n‐tuples of Abelian groups. In our case the group is ℤ4. © 2002 Wiley Periodicals, Inc. Random Struct. Alg. 20: 220–238, 2002
Evasive random walks and the clairvoyant demon
Authors: Abrams Aaron , Landau Henry , Landau Zeph , Pommersheim James , Zaslow Eric 
Published: October 2004

AbstractA pair of random walks (R, S) on the vertices of a graph G is successful if two tokens moving one at a time can be scheduled (moving only one token at a time) to travel along R and S without colliding. We consider questions related to P. Winkler's clairvoyant demon problem, which asks whether for random walks R and S on G, Pr[(R, S)is successful] >0. We introduce the notion of an evasive walk on G: a walk S so that for a random walk R on G, Pr[(R, S)is successful] >0. We characterize graphs G having evasive walks, giving explicit constructions on such G. Also, we show that on a cycle, the tokens must collide quickly with high probability. © 2002 Wiley Periodicals, Inc. Random Struct. Alg. 20: 220–229, 2002
The group‐noted state transition method applied to a PC management system
Authors: Hiyama Kunio 
Published: October 2004

AbstractTo improve software productivity, my colleagues and I pointed out in a previous paper that the state transition method is suitable as the functional description and implementation method. In that paper we proposed the distributed state transition method, which was derived from the model of distributed sequential machines and showed results obtained by applying it to an electronic switching system. In this paper, to enlarge the application range of the state transition method, I consider applying it to a PC management database system, and propose a new integrated design method derived from the single sequential machine model as being suitable. First I propose the “group‐noted state transition method” by introducing the sequential machine model. Then I propose this design method as follows. Initially, the function of the outer world of the system is classified into several groups, and management jobs are then divided into the same number of groups corresponding to them. The database information can also be classified in the same way and can support the design of the database system. After that, the state transition description is defined from the input/output information to/from the groups of the outer world. Furthermore, the method of notation in which the status group is added to the status name is proposed by classifying statuses using the concept of the management cycle. I also propose a new method for designing the software structure in which state transition diagram information is stored in the database system by converting it to table format. Results clarify that it is possible to make an integrated management database system by using this state transition method. They also clarify how to make a more advanced system by cooperating with the workflow system. © 2001 Scripta Technica, Syst Comp Jpn, 32(10): 13–21, 2001