bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of Polyion Complex Capsule and Fiber of Chitosan and Gellan-Sulfate at Aqueous Interface
Authors: Yamamoto Hiroyuki , Ohkawa Kousaku , Nakamura Emi , Miyamoto Keiichi , Komai Takashi
Published: October 2003

The electrostatic interaction between polysaccharides has been studied. Different characteristic surface structures, such as true spheres and fibrous forms, are made from gellan-sulfate (GS) and chitosan via polyion complex (PIC) formation. When a chitosan solution is added dropwise into a GS solution, spherical droplets form in the GS solution. The procedure makes true spherical capsules with various diameters, which are stable enough for finger pinching or magnetic stirring in distilled water. The soft droplet capsule is acid resistant, alkali resistant, and stable in boiling water. When an aqueous GS solution is added into an aqueous chitosan solution without mixing, a film of PIC is formed at the interface. When this PIC film is withdrawn from the interface, a fiber line forms in the wet states. After the intact wet fiber is dried in air, a strong fiber forms. The tensile strength of the strongest fiber created is 196 MPa. The swelling degree of the capsules and the strength of the fibers depend on the degree of sulfation of gellan.
Association of polyadenylation cleavage factor I with U1 snRNP
Authors: AWASTHI SITA , ALWINE JAMES C.
Published: October 2003

Splicing and polyadenylation factors interact for the control of polyadenylation and the coupling of splicing and polyadenylation. We document an interaction between the U1 snRNP and mammalian polyadenylation cleavage factor I (CF Im), one of several polyadenylation factors needed for the cleavage of the pre-mRNA at the polyadenylation site. Sucrose density gradient centrifugation demonstrated that CF Im separated into two fractions, a light fraction which contained the known CF Im subunits (72, 68, 59, and 25 kD), and a heavy fraction, rich in snRNPs, which contained predominately the 68- and 25-kD CF Im subunits. Using specific antibodies we found that the heavy fraction contains U1 snRNP/CF Im coprecipitable complexes. These complexes were insensitive to RNase treatment, suggesting that the coprecipitation is not due to RNA tethering. In vitro binding experiments show that both the 68- and 25-kD subunits bind to and comigrate with U1 snRNP. In addition, the 25-kD CF Im subunit binds specifically to the 70K protein of U1 snRNP (U1 70K). This binding may account for the CF Im/U1 snRNP interaction. During these studies we found that mAb 2.73 (mAb 2.73), an established U1 70K antibody, efficiently precipitates the bulk of the CF Im from cellular extracts. Because mAb 2.73 has been used in a number of previous studies related to the U1 snRNP and the U1 70K protein, the precipitation of CF Im must be considered in evaluating past and future data based on the use of mAb 2.73.
RNA–protein interactions promote asymmetric sorting of theASH1mRNA ribonucleoprotein complex
Authors: GONSALVEZ GRAYDON B. , LEHMANN KATRINA A. , HO DEREK K. , STANITSA ELENI S. , WILLIAMSON JAMES R. , LONG ROY M.
Published: October 2003

InSaccharomyces cerevisiae,ASH1mRNA is localized to the tip of daughter cells during anaphase of the cell cycle.ASH1mRNA localization is dependent on fourcis-acting localization elements as well as Myo4p, She2p, and She3p. Myo4p, She2p, and She3p are hypothesized to form a heterotrimeric protein complex that directly transportsASH1mRNA to daughter cells. She2p is an RNA-binding protein that directly interacts withASH1 cis-acting localization elements and associates with She3p. Here we report the identification of seven She2p mutants—N36S, R43A, R44A, R52A, R52K, R63A, and R63K—that result in the delocalization ofASH1mRNA. These mutants are defective for RNA-binding activity but retain the ability to interact with She3p, indicating that a functional She2p RNA-binding domain is not a prerequisite for association with She3p. Furthermore, the nuclear/cytoplasmic distribution for the N36S and R63K She2p mutants is not altered, indicating that nuclear/cytoplasmic trafficking of She2p is independent of RNA-binding activity. Using the N36S and R63K She2p mutants, we observed that in the absence of She2p RNA-binding activity, neither Myo4p nor She3p is asymmetrically sorted to daughter cells. However, in the absence of She2p, Myo4p and She3p can be asymmetrically segregated to daughter cells by artificially tethering mRNA to She3p, implying that the transport and/or anchoring of the Myo4p/She3p complex is dependent on the presence of associated mRNA.
The roles of endonucleolytic cleavage and exonucleolytic digestion in the 5′-end processing of S. cerevisiae box C/D snoRNAs
Authors: LEE CHRISSIE YOUNG , LEE ALBERT , CHANFREAU GUILLAUME
Published: October 2003

Small nucleolar RNAs (snoRNAs) play important roles in ribosomal RNA metabolism. In Saccharomyces cerevisiae, box C/D snoRNAs are synthesized from excised introns, polycistronic precursors, or independent transcription units. Previous studies have shown that only a few independently transcribed box C/D snoRNAs are processed at their 5′ end. Here we describe 12 additional independently transcribed box C/D snoRNAs that undergo 5′-end processing. 5′ Extensions found in the precursors of these snoRNAs contain cleavage sites for Rnt1p, the S. cerevisiae homolog of RNase III, and unprocessed precursors accumulate in vivo in the absence of Rnt1p. Rnt1p cleavage products were identified in vivo when the 5′ → 3′ exonucleases Xrn1p and Rat1p are inactivated (xrn1Δ rat1-1) and in vitro using model RNA substrates and recombinant Rnt1p. Some of these snoRNAs show increased levels of unprocessed precursors when the rnt1Δ deletion is combined to the xrn1Δ rat1-1 mutation, suggesting that these exonucleases participate in the 5′ processing or the degradation of the snoRNA precursors. Unprocessed precursors are not significantly destabilized in the absence of the trimethylguanosine capping enzyme Tgs1p, suggesting that a 5′ monomethyl cap is sufficient to ensure stabilization of these precursors. These results demonstrate that the majority of independently transcribed box C/D snoRNAs from the yeast genome undergo 5′-end processing and that the Rnt1p endonuclease and the Xrn1p and Rat1p 5′ → 3′exonucleases have partially redundant functions in the 5′-end processing of these snoRNAs.
TheSaccharomyces cerevisiaeU2 snRNA:pseudouridine-synthase Pus7p is a novel multisite–multisubstrate RNA:Ψ-synthase also acting on tRNAs
Authors: BEHM-ANSMANT ISABELLE , URBAN ALAN , MA XIAOJU , YU YI-TAO , MOTORIN YURI , BRANLANT CHRISTIANE
Published: October 2003

TheSaccharomyces cerevisiaePus7 protein was recently characterized as a novel RNA:pseudouridine (Ψ)-synthase acting at position 35 in U2 snRNA. However, U2 snRNA was the only potential substrate tested for this enzyme. In this work, we demonstrated that although Pus7p is responsible for the formation of only one of the six Ψ residues present in yeast UsnRNAs, it catalyzes U to Ψ conversion at position 13 in cytoplasmic tRNAs and at position 35 in pre-tRNATyr. Sites of RNA modification by Pus7p were identified by analysis of the in vivo RNA modification defects resulting from the absence of active Pus7p production and by in vitro tests using extracts from WT and genetically modified yeast cells. For demonstration of the direct implication of Pus7p in RNA modification, the activity of the WT and mutated Pus7p recombinant proteins was tested on in vitro produced tRNA and pre-tRNA transcripts. Mutation of an aspartic acid residue (D256) that is conserved in all Pus7 homologs abolishes the enzymatic activity both in vivo and in vitro. This suggests the direct involvement of D256 in catalysis. Target sites of Pus7p in RNAs share a common sequence Pu(G/C)UNΨAPu (Pu = purine, N = any nucleotide), which is expected to be important for substrate recognition. Modification of tRNAs by Pus7p explains the presence of Pus7p homologs in archaea and some bacteria species, which do not have U2 snRNA, and in vertebrates, where Ψ34 (equivalent to Ψ35 in yeast) formation in U2 snRNA is an H/ACA snoRNA guided process. Our results increase the number of known RNA modification enzymes acting on different types of cellular RNAs.
Coincident Hfq binding and RNase E cleavage sites on mRNA and small regulatory RNAs
Authors: MOLL ISABELLA , AFONYUSHKIN TARAS , VYTVYTSKA ORESTA , KABERDIN VLADIMIR R. , BLÄSI UDO
Published: October 2003

The Escherichia coli RNA chaperone Hfq was discovered originally as an accessory factor of the phage Qβ replicase. More recent work suggested a role of Hfq in cellular physiology through its interaction with ompA mRNA and small RNAs (sRNAs), some of which are involved in translational regulation. Despite their stability under certain conditions, E. coli sRNAs contain putative RNase E recognition sites, that is, A/U-rich sequences and adjacent stem–loop structures. We show herein that an RNase E cleavage site coincides with the Hfq-binding site in the 5′-untranslated region of E. coli ompA mRNA as well as with that in the sRNA, DsrA. Likewise, Hfq protects RyhB RNA from in vitro cleavage by RNase E. These in vitro data are supported by the increased abundance of DsrA and RyhB sRNAs in an RNase E mutant strain as well as by their decreased stability in a hfq− strain. It is commonly believed that the RNA chaperone Hfq facilitates or promotes the interaction between sRNAs and their mRNA targets. This study reveals another role for Hfq, that is, protection of sRNAs from endonucleolytic attack.
Structural organization of a viral IRES depends on the integrity of the GNRA motif
Authors: FERNÁNDEZ-MIRAGALL OLGA , MARTÍNEZ-SALAS ENCARNACIÓN
Published: October 2003

Little is known about the tertiary structure of internal ribosome entry site (IRES) elements. The central domain of foot-and-mouth disease (FMDV) IRES, named 3 or I, contains a conserved GNRA motif, essential for IRES activity. We have combined functional analysis with RNA probing to define its structural organization. We have found that a UNCG motif does not functionally substitute the GNRA motif; moreover, binding of synthetic GNRA stem–loops to domain 3 was significantly reduced in RNAs bearing UCCG or GUAG substitutions. The apical region of domain 3 consists of a four-way junction where residues of the GNRA tetraloop are responsible for the organization of the adjacent stem–loops, as deduced from ribonucleases and dimethyl sulfate accessibility. A single A-to-G substitution in the fourth position of this motif led to a strong RNA reorganization, affecting several nucleotides away in the secondary structure of domain 3. The study of mutants bearing UNCG or GUAG tetraloops revealed lack of protection to chemical attack in native RNA at specific nucleotides relative to the parental GUAA, suggesting that the GNRA motif dictates the organization and stability of domain 3. This effect is likely mediated by the interaction with distant residues. Therefore, the GNRA motif plays a crucial role in the organization of IRES structure with important consequences on activity.
Oxaliplatin/Fluorouracil/Leucovorin in Advanced Colorectal Carcinoma: An Asian Experience
Authors: Lim Elaine Hsuen , Lim Robert Seng Cheong , Wu Tuck Seng , Kong Hwai Loong
Published: October 2003

BACKGROUND:

Oxaliplatin/fluorouracil/leucovorin (FOLFOX4) is an effective and generally well-tolerated regimen in Western studies of metastatic colorectal carcinoma.

OBJECTIVE:

To evaluate the objective tumor responses and toxicities of the FOLFOX4 regimen in a predominantly Chinese population with advanced colorectal carcinoma in Singapore.

METHODS:

Forty-seven consecutive patients were enrolled in a retrospective study between March 1998 and December 2001. FOLFOX4 was first-line treatment in 36% of these patients, second-line in 36%, third-line in 17%, and fourth-line in 11%. Tumor responses were assessed radiologically, and toxicities were graded by the National Cancer Institute common toxicity system.

RESULTS:

The objective response rate (all partial responses) was 45%, and stable disease was achieved in 35% of the patients. There were no deaths due to toxicity. Mild to moderate peripheral sensory neuropathy affected half of the patients, with 1 report of cold exacerbation in this tropical series. The rate of hypersensitivity reactions to oxaliplatin was 11%, and they usually occurred late in the treatment course.

CONCLUSIONS:

FOLFOX4 has good efficacy in metastatic colorectal carcinoma in our local population, but the rate of hypersensitivity reactions to oxaliplatin was high.
Adverse Reactions to Trimethoprim/Sulfamethoxazole in AIDS
Authors: Floris-Moore Michelle A , Amodio-Groton Maria I , Catalano Michela T
Published: October 2003

OBJECTIVE:

To report the case of a woman with AIDS who developed tremor, acute pancreatitis, and elevated serum creatinine levels while receiving trimethoprim/sulfamethoxazole (TMP/SMX).

CASE SUMMARY:

A 37-year-old Puerto Rican woman with AIDS, HIV nephropathy, and a recent history of disseminated histoplasmosis presented with fever, nonproductive cough, pancytopenia, and elevated transaminase and alkaline phosphatase levels. Serum creatinine was near her baseline level of 2.9 mg/dL. Treatment was started with amphotericin B lipid complex for histoplasmosis and intravenous TMP/SMX for presumed Pneumocystis carinii pneumonia. Two days later, the patient developed a high-frequency tremor and severe abdominal pain, and serum creatinine increased to 5.6 mg/dL. TMP/SMX was discontinued, after which the patient's symptoms resolved within 72 hours and serum creatinine returned to baseline levels.

DISCUSSION:

A high incidence of adverse reactions to TMP/SMX has been reported among HIV-infected persons. Toxic sulfamethoxazole metabolites may elicit hypersensitivity reactions. Trimethoprim can inhibit renal creatinine secretion, leading to high serum creatinine levels. Trimethoprim also inhibits dihydrofolate reductase, causing decreased dopamine production, which may lead to parkinsonian symptoms. Use of the Naranjo probability scale indicated a probable relationship between the adverse effect and TMP/SMX.

CONCLUSIONS:

The high frequency and wide range of potential adverse effects associated with the use of TMP/SMX in HIV-infected persons require that clinicians consider drug toxicity as a cause of new symptoms in patients receiving this medication.
Overcoming Recurrent Cutaneous Reactions from Imatinib Using Once-Weekly Dosing
Authors: Tanvetyanon Tawee , Nand Sucha
Published: October 2003

OBJECTIVE:

To describe the use of once-weekly imatinib in a patient who developed recurrent cutaneous reactions associated with imatinib.

CASE SUMMARY:

A 65-year-old Asian woman received investigational treatment with imatinib 300 mg/d as maintenance therapy for acute lymphoblastic leukemia. Exfoliative dermatitis developed after 3 weeks of administration. Attempts to resume imatinib at lower dosages, with or without a low-dose corticosteroid, resulted in recurrent reactions. Once-weekly administration of imatinib, however, produced a tolerable, less severe reaction. After the woman had experienced exfoliative dermatitis for 4 months, the reaction subsided and disappeared.

DISCUSSION:

Once-weekly administration of imatinib allowed imatinib therapy to continue, and this dosing schedule appeared safe. Patients with severe cutaneous reactions who need to continue imatinib may benefit from this strategy, along with lowering of the dosage and premedication with a corticosteroid.

CONCLUSIONS:

In a patient with recurrent cutaneous reactions due to imatinib, a once-weekly dosing schedule was safe, well tolerated, and associated with eventual disappearance of the reaction.
Monitoring of 4‐hydroxybutyric acid levels in body fluids during vigabatrin treatment in succinic semialdehyde dehydrogenase deficiency
Authors: Ergezinger Katrin , Jeschke Reinhard , Frauendienst‐Egger Georg , Korall Herbert , Gibson K. Michael , Schuster Volker H.
Published: October 2003

We report the successful treatment using low‐dose vigabatrin (21.5–34mg/kg/day) of a 10‐year‐old girl with succinic semialdehyde dehydrogenase (SSADH) deficiency We verified that 4‐hydroxybutyric acid (GHB) concentrations in serum, cerebrospinal fluid, and urine continuously decreased in parallel with significant clinical improvement. Our results suggest that GHB quantification in physiological fluids may be a useful laboratory parameter for monitoring efficacy of vigabatrin treatment in SSADH deficiency. Ann Neurol 2003;54:686–689
Synthesis and thermal studies of poly(N‐acryloyl,N′‐cyanoacetohydrazide) complexes with Co(II), Fe(III), and UO2(II) ions
Authors: El‐Mossalamy E. H. , Al‐Thabaiti Shaeel A.
Published: October 2003

Polymer complexes with uranium, cobalt, and iron chlorides were synthesized and investigated by elemental analysis, electronic (uv–visible), IR vibration, and magnetic moment measurements. The thermal stabilities of N‐acryloyl,N′‐cyanoacetohydrazide (ACAH) homopolymers and polymer complexes of poly(ACAH) (PACAH) with metal chlorides were studied thermogravimetrically. The rates of polymerization of PACAH in the absence and presence of metal chlorides were studied. The activation energies of the degradation of the homopolymer and polymer complexes were calculated using the Arrhenius equation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3354–3358, 2003
Influence of titanium dioxide on crystallization behavior of an ethylene–propylene copolymer
Authors: Raimo M. , Martuscelli E.
Published: October 2003

Crystallization of an ethylene–propylene copolymer (E/P) filled with diverse weight percentages of titanium dioxide (TiO2) was performed under isothermal and nonisothermal conditions to investigate the influence of the inorganic substance on the nucleation and growth mechanisms of the matrix. The overall and radial crystallization rates of the composite materials were measured using, respectively, differential scanning calorimetry (DSC) and optical microscopy. The nucleation density of E/P spherulites as a function of composition was investigated by scanning electron microscopy (SEM), revealing a nucleating effect of TiO2. A comparison between the spherulitic texture of specimens showed a higher fineness of the composites relative to the neat matrix, whereas no changes of surface nucleation density were appreciable among composites within the explored compositional range. The thermal behavior is discussed in the light of the enhanced thermal conductivity of polymer composites, which conciliates the crystallization kinetics of the matrix, analyzed using the Avrami equation, to optical and SEM observations. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3409–3416, 2003
Does axonemal dynein push, pull, or oscillate?
Authors: Lindemann Charles B. , Hunt Alan J.
Published: October 2003

Dynein is the molecular motor that provides motive force in cilia and flagella. Dynein is anchored to the A‐subtubule of the outer doublets by a club‐shaped extension called the stem, which supports the large globular head of the molecule. Dynein forms an attachment or cross‐bridge to the B‐subtubule of the adjacent outer doublet through a slender appendage extending from the head that is called the stalk or alternately the B‐link. It is generally thought that the B‐link mediates the interdoublet transfer of force that bends the flagellum. This requires that energy released at the site of ATP hydrolysis, located in the globular head, be transferred as mechanical work to the microtubule binding site at the tip of the B‐link. It has been proposed that this is accomplished by a sideways or rotational translocation of the B‐link caused by a rotation of the globular head. An estimate of the stiffness of the B‐link and stem derived from the recently published data of Burgess et al. [2003: Nature 421:715–718] yields a maximum stiffness of 0.47 pN/nm for the B‐link and 0.1 pN/nm for the stem. The B‐link stiffness would allow transfer of 3.8 pN of force in response to an 8‐nm displacement of the B‐link tip. However, if as proposed the globular head of the dynein heavy chain is supported by the stem, the B‐link and stem elasticity are in series. Thus, the flexibility of the stem would limit the force that can be transferred laterally by the entire dynein heavy chain to 0.6 pN at 8 nm displacement. This force is insufficient to support flagellar motility. So, if the stem were the only support for the globular head, then force would have to be transmitted linearly along the axis defined by the stem and B‐link. Because this configuration is never observed, the hypothesis that dynein generates force by lateral displacement of the B‐link is more attractive, but requires that the globular head of the dynein is stabilized by an additional means of support during the power stroke. We propose that the microtubule affinity of the tip of the B‐link is independent of the ATP‐dependent powerstroke, and that detachment from the B‐subtubule is regulated by tension. A dynein cross‐bridge cycle that incorporates an anchored head, together with a ratchet‐like mechanism for microtubule translocation by the B‐link, would have distinct advantages. This mechanism may reconcile dynein oscillation and interdoublet sliding within one cross‐bridge mechanism. Cell Motil. Cytoskeleton 56:237–244, 2003. © 2003 Wiley‐Liss, Inc.
Sensorimotor corticocortical projections from rat barrel cortex have an anisotropic organization that facilitates integration of inputs from whiskers in the same row
Authors: Hoffer Zachary S. , Hoover John E. , Alloway Kevin D.
Published: October 2003

We used a dual anterograde‐tracing paradigm to characterize the organization of corticocortical projections from primary somatosensory (SI) barrel cortex. In one group of rats, biotinylated dextran amine (BDA) and Fluoro‐Ruby (FR) were injected into separate barrel columns that occupied the same row of barrel cortex; in the other group, the tracers were deposited into barrel columns residing in different rows. The labeled corticocortical terminals in the primary motor (MI) and secondary somatosensory (SII) cortices were plotted, and digital reconstructions of these plots were quantitatively analyzed. In all cases, labeled projections from focal tracer deposits in SI barrel cortex terminated in elongated, row‐like strips of cortex that corresponded to the whisker representations of the MI or SII cortical areas. When both tracers were injected into separate parts of the same SI barrel row, FR‐ and BDA‐labeled terminals tended to merge into a single strip of labeled MI or SII cortex. By comparison, when the tracers were placed in different SI barrel rows, both MI and SII contained at least two row‐like FR‐ and BDA‐labeled strips that formed mirror image representations of the SI injection sites. Quantitative analysis of these labeling patterns revealed three major findings. First, labeled overlap in SII was significantly greater for projections from the same barrel row than for projections from different barrel rows. Second, in the infragranular layers of MI but not in the supragranular layers, labeled overlap was significantly higher for projections from the same SI barrel row. Finally, in all layers of SII and in the infragranular layers of MI, the amount of labeled overlap was proportional to the proximity of the tracer injection sites. These results indicate that SI projections to MI and SII have an anisotropic organization that facilitates the integration of sensory information received from neighboring barrels that represent whiskers in the same row. J. Comp. Neurol. 466:525–544, 2003. © 2003 Wiley‐Liss, Inc.
Timing and topography of nucleus magnocellularis innervation by the cochlear ganglion
Authors: Molea David , Rubel Edwin W
Published: October 2003

This series of experiments examined the arrival and organization of cochlear nerve axons in the primary auditory brainstem nucleus, nucleus magnocellularis (NM), of the chick. DiI and DiD were injected into the cochlear nerve, cochlear ganglion, and basilar papilla (i.e., avian cochlea) in fixed tissue and labeled axons were studied in NM and its vicinity. Cochlear nerve axons first penetrate NM between stages 29 (E6) and 36 (E10). Axons penetrate NM in a middle‐to‐posterior‐to‐anterior developmental sequence; the anterior, high‐frequency region of NM receives axons last. When cochlear nerve axons arrive in the NM, they are already organized in a topographic map related to the position of their cell bodies along the basilar papilla, foreshadowing the tonotopic mapping observed between NM and the basilar papilla later in development. Evidence of a topographic map was also observed in the other primary auditory brainstem nucleus, nucleus angularis. These results indicate that topographic mapping of position (and ultimately characteristic frequency) between the basilar papilla and NM is established as cochlear nerve axons arrive in the NM prior to the onset of synaptic activity. J. Comp. Neurol. 466:577–591, 2003. © 2003 Wiley‐Liss, Inc.
Ultrastructural localization of the norepinephrine transporter in superficial and deep layers of the rat prelimbic prefrontal cortex and its spatial relationship to probable dopamine terminals
Authors: Miner Leeann H. , Schroeter Sally , Blakely Randy D. , Sesack Susan R.
Published: October 2003

The prefrontal cortex (PFC) is a likely site of action for the therapeutic efficacy of antidepressants that inhibit norepinephrine (NE) reuptake. Moreover, drugs that block the NE transporter (NET) increase extracellular levels of both NE and dopamine (DA), an interaction that may contribute to their therapeutic properties. To examine the subcellular localization of NET and to investigate the spatial relationships between presumed NE and DA axons within the rat prelimbic PFC, we combined immunogold–silver localization of NET with immunoperoxidase staining for the catecholamine synthetic enzyme tyrosine hydroxylase (TH). An additional aim was to quantify the proportion of profiles dually labeled for NET and TH to test the common observation that TH immunolabeling is relatively selective for DA axons. NET‐immunoreactive (NET‐ir) axonal profiles were typically unmyelinated and occasionally were observed to form symmetric axodendritic synapses. The majority of immunogold NET labeling was unexpectedly observed in the cytoplasm rather than on the plasma membrane. Furthermore, in tissue dually labeled for both NET and TH, only 8–10% of profiles contained both markers. Unlike observations for singly labeled profiles, gold–silver particles for NET in dually labeled axons were localized primarily to the plasmalemma. A systematic survey of terminals labeled only for TH revealed that they were typically separated by at least 1.2 μm from NET‐ir varicosities, and the two profile types were not seen to contact common targets. These results suggest that, in the rat PFC, NE axons (1) contain predominantly cytoplasmic NET, (2) infrequently contain TH immunolabeling, and (3) may interact with probable DA afferents by means of extrasynaptic mechanisms. J. Comp. Neurol. 466:478–494, 2003. © 2003 Wiley‐Liss, Inc.
Improved DNA flow cytometric, DNA ploidy, and S‐phase reproducibility between 15 laboratories in analysis of breast cancer using generalized guidelines
Authors: Baldetorp Bo , Bendahl Pär‐Ola , Fernö Mårten , Stål Olle
Published: October 2003

Background

Lack of generalized guidelines for DNA flow cytometric analysis (FCM) may be the main reason for its limited use in the clinical management of breast cancer.

Methods

After an initial interlaboratory reproducibility study (Round I), we concluded that it was the evaluation of the DNA histograms rather than the technical performance of the analysis that was the main reason for discordant results between laboratories. Guidelines for the interpretation of DNA histograms were therefore drawn up. We present here data from a new reproducibility study (Round II) using these guidelines.

Results

For 10 laboratories also participating in Round I, use of the guidelines increased the concordance in DNA ploidy status from 89% to 100% for the 46 samples used in both rounds. The concordance rate for SPF also increased; mean rs‐value increased from 0.81 to 0.88, and mean kappa value (lower two‐thirds versus upper third versus not reported) increased from 0.55 to 0.71. Five new laboratories, participating only in Round II, also agreed with the 10 original laboratories regarding DNA ploidy status. With the inclusion of all 15 laboratories, we obtained a mean rs‐value of 0.81 and a mean kappa value of 0.72 for SPF.

Conclusions

Generalized guidelines for DNA FCM increase interlaboratory agreement, which is highly important in clinical routines and in multicenter studies. Furthermore, inexperienced FCM laboratories using generalized guidelines can produce and interpret DNA FCM data equally as well as experienced laboratories. Cytometry Part A 56A:1–7, 2003. © 2003 Wiley‐Liss, Inc.
On functional properties of information filtering
Authors: Sawai Rie , Tsukamoto Masahiko , Terada Tsutomu , Loh Yin‐Huei , Nishio Shojiro
Published: October 2003

With the widespread use of satellite broadcasting and data broadcasting, the kind and amount of broadcast content are increasing rapidly. In an environment in which large amounts of data are received, it is very difficult for the user to locate the necessary data, and it is desirable to develop a filtering method that can automatically extract only the necessary data. A large number of filtering methods for such a purpose have been proposed. However, the mathematical basis for the qualitative representation of these methods has not been established, and there is as yet no method for qualitative evaluation and optimization of the method and no design of a declarative language for filtering. In this paper, filtering is defined as a function. By representing the properties of various filtering methods as conditions to be satisfied by the function, a mathematical basis for information filtering is established. The relations among the properties of the filtering methods are analyzed by identifying the inclusive relations among the constraints representing various properties. On the basis of the mathematical basis discussed in this paper, real filtering methods are classified. By selecting processing matched to the required properties, more efficient filtering will be realized. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 86(11): 37–49, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10199
Simulation model of surface acoustic wave motor considering tangential rigidity
Authors: Asai Katsuhiko , Kurosawa Minoru Kuribayashi
Published: October 2003

In order to attempt performance improvement of a surface acoustic wave motor, it is necessary to understand the contact condition between the stator substrate and the slider and to determine the relationship between the basic performance and the physical parameters. In this research, a simulation model taking into account the tangential rigidity on the stator substrate surface is proposed. The effects of parameters such as the friction coefficient, amplitude, and rigidity on the driving performance are elucidated. The validity of the proposed model is demonstrated by a comparison with the experimental results. In addition, detailed calculations are carried out, including determination of the normal position change of the slider by means of the simulation model. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(2): 54–66, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10098
Energy circulation methods for surface acoustic wave motor
Authors: Asai Katsuhiko , Kurosawa Minoru Kuribayashi , Higuchi Toshiro
Published: October 2003

It is important to improve efficiency of surface acoustic wave motors in order to achieve their commercialization. In the present research, the energy of the surface wave, which has previously not been used effectively for driving the slider, but been consumed in sound‐absorbing materials, is now circulated by two techniques, so that the surface wave is excited efficiently. Trial fabrication of surface acoustic wave motors using the energy circulation methods is carried out. It is confirmed that the traveling wave can actually be excited. In addition, the effectiveness of the energy circulation method is demonstrated by comparison of the driving performance with that in the absence of energy circulation methods. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(2): 10–19, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10132
Multistage carcinogenesis and the incidence of human cancer
Authors: Moolgavkar Suresh H. , Luebeck E. Georg
Published: October 2003

We consider the implications of multistage carcinogenesis for the incidence of cancer in human populations. When clonal expansion of partially altered cells is properly accounted for, we find it unnecessary to invoke genomic instability as an early event in malignant transformation. Environmental agents that increase the rate of clonal expansion of partially altered cells are efficient carcinogens. As a corollary, intervention strategies that decrease this rate are to be preferred to strategies that decrease the rate of early mutational events in carcinogenesis. © 2003 Wiley‐Liss, Inc.
Search for unknown tumor‐antagonizing genes
Authors: Imreh Stephan , Klein George , Zabarovsky Eugene R.
Published: October 2003

Following the ingenious prediction of Alfred Knudson in 1971, the first tumor suppressor gene, RB1, has been isolated. Its product, the RB1 protein, was found to play a major role in the control of the cell cycle. The loss of heterozygosity (LOH) technique, introduced by Cavenee and colleagues, was an important milestone toward the confirmation of Knudson's hypothesis and the identification of the gene. Subsequently, the LOH technique has provided important clues that have led to the discovery of other tumor suppressor genes. Most of them play important roles in the regulation of the cell cycle and/or of apoptosis. Circumstantial evidence suggests that still other and perhaps many unknown genes may participate in the protection of the organism against malignant growth. The numerous genome losses in tumors, detected by LOH, comparative genomic hybridization, and by cytogenetic techniques, support this possibility. The early work of one of us (G.K.), together with Henry Harris and Francis Wiener, had shown that the malignant phenotype can be suppressed by hybridizing malignant with low‐ or non‐tumorigenic cells. However, analysis of this phenomenon failed to assign the inhibition of tumorigenicity to any particular gene. We have pursued the search for new tumor‐antagonizing genes with two unconventional approaches, focusing on human chromosomal subband 3p21.3, a region frequently targeted by cytogenetically detectable deletions. We have detected four clusters of candidate tumor suppressor genes at 3p21.3 by a combination of deletion mapping and the “elimination test.” These findings raise the question whether the number and variety of genes that may contribute to the defense against uncontrolled proliferation may have been underestimated. © 2003 Wiley‐Liss, Inc.
Differential expression and localization of the phosphorylated and nonphosphorylated neurofilaments during the early postnatal development of rat hippocampus
Authors: Lopez‐Picon F.R. , Uusi‐Oukari M. , Holopainen I.E.
Published: October 2003

Neurofilament (NF) proteins are expressed in most mature neurons in the central nervous system. Although they play a crucial role in neuronal growth, organization, shape, and plasticity, their expression pattern and cellular distribution in the developing hippocampus remain unknown. In the present study, we have used Western blotting and immunocytochemistry to study the low‐ (NF‐L), medium‐ (NF‐M), and high‐ (NF‐H) molecular‐weight NF proteins; phosphorylated epitopes of NF‐M and NF‐H; and a nonphosphorylated epitope of NF‐H in the early postnatal (through P1–P21) development of the rat hippocampus. During the first postnatal week, NF‐M was the most abundantly expressed NF, followed by NF‐L, whereas the expression of NF‐H was very low. Through P7–P14, the expression of NF‐H increased dramatically and later began to plateau, as also occurred in the expression of NF‐M and NF‐L. At P1, no NF‐M immunopositive cell bodies were detected, but cell processes in the CA1‐CA3 fields were faintly immunopositive for NF‐M and for the phosphorylated epitopes of NF‐M and NF‐H. At P7, CA3 pyramidal neurons were strongly immunopositive for NF‐L and NF‐H, but not for NF‐M. The axons of granule cells, the mossy fibers (MFs), were NF‐L and NF‐M positive through P7–P21 but were NF‐H immunonegative at all ages. Although they stained strongly for the phosphorylated NF‐M and NF‐H at P7, the staining intensity sharply decreased at P14 and remained so at P21. The cell bodies of CA1 pyramidal neurons and granule cells remained immunonegative against all five antibodies in all age groups. Our results show a different time course in the expression and differential cell type and cellular localization of the NF proteins in the developing hippocampus. These developmental changes could be of importance in determining the reactivity of hippocampal neurons in pathological conditions in the immature hippocampus. © 2003 Wiley‐Liss, Inc.
Impaired interleukin‐1 signaling is associated with deficits in hippocampal memory processes and neural plasticity
Authors: Avital Avi , Goshen Inbal , Kamsler Ariel , Segal Menahem , Iverfeldt Kerstin , Richter‐Levin Gal , Yirmiya Raz
Published: October 2003

The cytokine interleukin‐1 (IL‐1) is produced by peripheral immune cells as well as glia and neurons within the brain; it plays a major role in immune to brain communication and in modulation of neural, neuroendocrine, and behavioral systems during illness. Although previous studies demonstrated that excess levels of IL‐1 impaired memory processes and neural plasticity, it has been suggested that physiological levels of IL‐1 are involved in hippocampal‐dependent memory and long‐term potentiation (LTP). To examine this hypothesis, we studied IL‐1 receptor type I knockout (IL‐1rKO) mice in several paradigms of memory function and hippocampal plasticity. In the spatial version of the water maze test, IL‐1rKO mice displayed significantly longer latency to reach a hidden platform, compared with wild‐type controls. Furthermore, IL‐1rKO exhibited diminished contextual fear conditioning. In contrast, IL‐1rKO mice were similar to control animals in hippocampal‐independent memory tasks; i.e., their performance in the visually guided task of the water maze and the auditory‐cued fear conditioning was normal. Electrophysiologically, anesthetized IL‐1rKO mice exhibited enhanced paired‐pulse inhibition in response to perforant path stimulation and no LTP in the dentate gyrus. In vitro, decreased paired‐pulse responses, as well as a complete absence of LTP, were observed in the CA1 region of hippocampal slices taken from IL‐1rKO mice compared with WT controls. These results suggest that IL‐1 contributes to the regulation of memory processes as well as short‐ and long‐term plasticity within the hippocampus. These findings have important implications to several conditions in humans, which are associated with long‐term defects in IL‐1 signaling, such as mutations in the IL‐1 receptor accessory protein‐like gene, which are involved in a frequent form of X‐linked mental retardation. © 2003 Wiley‐Liss, Inc.
Loss of FHIT protein expression is a marker of adverse evolution in good prognosis localized breast cancer
Authors: Ginestier Christophe , Bardou Valérie‐Jeanne , Popovici Cornel , Charafe‐Jauffret Emmanuelle , Bertucci François , Geneix Jeannine , Adélaïde José , Chaffanet Max , Hassoun Jacques , Viens Patrice , Jacquemier Jocelyne , Birnbaum Daniel
Published: October 2003

TheFHITtumor suppressor gene, which encompasses the fragile siteFRA3Bat 3p14.2, is altered frequently in many types of human cancers. To determine its importance as a prognostic marker in breast cancer, the expression of the FHIT protein was studied in a series of 452 breast carcinomas by using immunohistochemistry on sections of tissue microarrays. Three distinct levels of FHIT expression were observed: in 154 cases (34.1%) expression was unchanged as compared to normal level; in 78 (17.2%) no expression was found; in the remaining 220 cases (48.7%), expression was intermediate. Overall, two‐thirds of the cases had abnormal levels of the protein. Absence of FHIT was significantly associated with a higher grade (p< 0.01) and absence of hormone receptors (p< 0.001). The patients were separated into Group I (153 node‐negative good prognosis patients who did not receive adjuvant chemotherapy) and Group II (226 high‐risk patients treated by adjuvant chemotherapy) according to the St.‐Gallen conference consensus. The median follow‐up was 48 months. Among Group I but not Group II patients, a multivariate analysis showed that FHIT expression was significantly associated with disease‐free survival. The relative risk of recurrence for FHIT‐negative Group I patients was 2.37 (1.21–4.64;p= 0.03). Thus, among the patients who present with tumors of apparent good prognosis, FHIT is an independent prognostic factor that distinguishes a subgroup of patients who could benefit from adjuvant treatment. © 2003 Wiley‐Liss, Inc.
Comparison of age at first full‐term pregnancy between women with breast cancer and women with benign breast diseases
Authors: Lagiou Areti , Lagiou Pagona , Vassilarou Dorothy‐Stamatia , Stoikidou Melpomeni , Trichopoulos Dimitrios
Published: October 2003

Benign breast diseases have a broadly similar risk profile to that of breast cancer, possibly reflecting a similar underlying endocrine milieu. We have hypothesized that a crucial distinction between breast cancer and benign breast diseases is that mammary gland terminal differentiation has not been successfully accomplished among women who tend to develop breast cancer. From October 2001 to December 2002, information concerning breast cancer risk factors and sociodemographic characteristics was collected from 174 women with breast cancer and 116 women with benign breast diseases, all 30 years old or older, who were histologically diagnosed at a major prevention center in Athens, Greece. Among the examined breast cancer risk factors, only age at first full‐term pregnancy was significantly associated with the odds of having breast cancer rather than benign breast disease, and the association was evident among premenopausal [odds ratio (OR) per 5 years = 1.76, 95% confidence interval (CI) 1.10–2.93] and postmenopausal (OR = 2.10, 95% CI 1.16–3.71) women, as well as among all women (OR = 1.93, 95% CI 1.34–2.70). There was no evidence that any of the remaining breast cancer risk factors could discriminate between breast cancer and benign breast diseases. We conclude that early age at first pregnancy may convey substantial protection against breast cancer risk among women with benign breast diseases, probably operating through induction of terminal differentiation of mammary gland cells. The finding is accentuated by the fact that women with benign breast diseases are already at a relatively high risk for breast cancer. © 2003 Wiley‐Liss, Inc.
Use of AFM to probe the adsorption strength and time‐dependent changes of albumin on self‐assembled monolayers
Authors: Dupont‐Gillain Ch. C. , Fauroux C. M. J. , Gardner D. C. J. , Leggett G. J.
Published: October 2003

The adsorption kinetics of human serum albumin (HSA) on CH3‐ and COOH‐terminated self‐assembled monolayers (SAMs) has been investigated using radioassays and atomic force microscopy (AFM). On both surfaces, the amount of HSA adsorbed reached a plateau after 30 min. The plateau level was higher on the CH3 compared to the COOH surface. The adhesion force (Fadh), measured using Si3N4 AFM tips in water, decreased with time of contact with the HSA solution on the CH3 surface. This time‐dependent change in the adhesiveness of the adsorbed protein is best explained by a change in the conformation or orientation. In contrast, Fadh was independent of the time of contact with the HSA solution on the COOH surface, indicating that once adsorbed, the HSA molecules do not undergo further conformation or orientation changes. The perturbation induced by scanning with the AFM in water on the adsorbed HSA layers was greater on CH3 surfaces than on COOH surfaces, suggesting a weaker protein–substratum interaction on the CH3‐terminated SAMs. This was further confirmed by a stronger desorption of HSA following sodium dodecyl sulfate (SDS) treatment on the CH3 surface compared to the COOH surface. Taken together, these data suggest that for COOH SAMs, (1) there is a strong interaction between HSA and the substratum; (2) there is an absence of reorientation with time; and (3) there is a smaller amount of adsorbed protein at 24 h, possibly due to increased but rapid spreading/denaturation of the protein. On the CH3 surface, less deformation of HSA occurs and the molecules maintain a higher mobility at short adsorption times. AFM measurements performed after aging of an adsorbed HSA layer in buffer suggests the role played by HSA in solution in determining the time‐dependent conformation and/or orientation changes. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 548–558, 2003
Interactions of antithrombin and proteins in the plasma contact activation system with immobilized functional heparin
Authors: Cornelius Rena M. , Sanchez Javier , Olsson Per , Brash John L.
Published: October 2003

The interactions of antithrombin (AT) and the contact phase clotting factors with two commercially available heparinized surfaces are reported. The Carmeda (CBAS) and Corline surfaces along with controls (a sulfonated polyethylene surface and a CBAS analog in which the heparin used was devoid of specific AT‐binding sequences) were exposed to human plasma. Adsorbed proteins were eluted and examined by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and immunoblotting. The CBAS and Corline surfaces adsorbed large amounts of AT, whereas adsorption on the controls was negligible. Immunoblots for the four contact phase clotting factors indicated less contact activation on the CBAS and Corline surfaces than on the controls. Determination of adsorbed functional AT using a FXa inhibition assay showed that the CBAS surface adsorbed about 4 times as much AT as the Corline surface. Adsorption of AT to the control surfaces was minimal. Assays for adsorbed FXII and FXIIa based on kallikrein generation showed that all four surfaces adsorbed similar amounts of FXII. However, on the controls, most of the FXII was in activated form, whereas on the CBAS and Corline surfaces very little activation occurred. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 475–483, 2003
A study on the effect of dual blasting with TiO2 on titanium implant surfaces on functional attachment in bone
Authors: Rønold Hans Jacob , Lyngstadaas Ståle Petter , Ellingsen Jan Eirik
Published: October 2003

In the present study, the effect of a dual treatment of titanium implants and the subsequent bone response after implantation were investigated. Coin‐shaped c.p. titanium implants were placed into the tibias of 12 rabbits. The implant, which was dually blasted with TiO2 particles of two different sizes, was compared with implants that were blasted with only one of these particle sizes. Implants in group 1 were grit blasted with small particles, 22–28 μm in size, and group 2 with coarser particles, 180–220 μm size. These two treatments gave different surface micro textures. To test the effect of a combination of two different treatments, group 3 implants were blasted first with the 180‐ to 220‐μm and subsequently with the 22‐ to 28‐μm particles. The surface topography of the implant specimens was examined by scanning electron microscopy and by a confocal laser scanner and a numeric evaluation of Sa, St, and Sdr was recorded. Group 2 implants, which were blasted with only the coarse particles, showed a significantly better functional attachment (p < 0.001) than the other two groups. Group 1, which was blasted with only small particles, showed the lowest retention in bone. There was a positive correlation between the topographical and mechanical evaluation of the surfaces. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 524–530, 2003