bluuebunny/crossref_metadata_2025 huggingface dataset:
Inactivation of RASSF2A by promoter methylation correlates with lymph node metastasis in nasopharyngeal carcinoma
Authors: Zhang Zhe , Sun Di , Van Do Nguyen , Tang Anzhou , Hu Lifu , Huang Guangwu
Published: September 2006

RASSF2 can bind directly to K‐Ras and function as a negative effector of Ras protein. RASSF2A is the only isoform of RASSF2 that contains CpG islands in its promoter and it has been reported to be inactivated by its promoter methylation in several human cancers. In the present study, we investigated the correlation of RASSF2A expression with its promoter methylation in nasopharyngeal carcinoma (NPC). Expression of RASSF2A was down‐regulated in 80% (4/5) of NPC cell lines. Decreased RASSF2A expression was also observed in NPC primary tumors compared with normal nasopharyngeal epithelia. Promoter methylation of RASSF2A could be detected in all the RASSF2A‐silenced cell lines (4/5) of the NPC cell lines and 50.9% (27/53) of primary tumors, but not in any of the normal epithelia. RASSF2A‐methylated cases showed a significantly lower level of RASSF2A expression than unmethylated cases. Loss of RASSF2A expression can be greatly restored by the methyltransferase inhibitor 5‐aza‐dC in NPC cell lines. In addition, patients with methylated RASSF2A presented a higher frequency of lymph node metastasis (p < 0.05). Ectopic expression of RASSF2A in RASSF2A‐silenced and ‐methylated NPC cell line CNE2 shows that RASSF2A could inhibit cell cycle progression, colony formation and cell migration, which provided further evidence that RASSF2A is a candidate tumor suppressor gene. In conclusion, RASSF2A, a candidate tumor suppressor gene (TSG), is frequently inactivated by its promoter methylation and this aberrant methylation correlates with lymph node metastasis in NPC. © 2006 Wiley‐Liss, Inc.
BMP‐7 and CBFA1 in allograft bone in vivo bone formation and the influence of γ‐irradiation
Authors: Chen J.B. , Yu Y. , Yang J‐L. , Morgan D.A.F. , Walsh W.R.
Published: September 2006

An initial study showed that morselized human bone grafts were osteoconductive and osteoinductive when implanted in nude rat tibial window defects, and 25 kGy of γ‐irradiation significantly reduced those properties. The mechanism of the osteoinductivity and the influence of γ‐irradiation required further investigation. In this study we assessed the paraffin sections of seven morselized human bone grafts implanted into rat tibial defects for 3 weeks after being treated with 0, 15, or 25 kGy γ‐radiation respectively. Osteoclast‐like cell counting and protein expressions of bone morphogenetic protein‐7 (BMP‐7), core binding factor α1 (CBFA1), and proliferating cell nuclear antigen (PCNA) were investigated and the positive signals were quantitatively analyzed. More new bone formation was observed in the 0 and 15 kGy groups compared with 25 kGy groups. The newly formed bones were found mainly from the intact cortex into the defects bridged by the implanted grafts. A dense staining of BMP‐7 and CBFA1 was noted in the osteoblast‐like cells in those areas. The BMP‐7 and CBFA1 staining was also seen in the cells surrounding the implanted grafts in the centre areas of the defects in distance from the intact cortex. Quantitative analysis of immunohistochemical staining of the centre areas of the defects showed that γ‐irradiation (15 and 25 kGy) significantly reduced the expression of CBFA1 and BMP‐7. In conclusion, morselized human bone grafts may contain some factors, which induced osteoblast lineage differentiation and bone formation and γ‐irradiation damages those bone inducing factors. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Fabrication and characterization of hydrophilized porous PLGA nerve guide conduits by a modified immersion precipitation method
Authors: Oh Se Heang , Lee Jin Ho
Published: September 2006

Nerve guide conduits (NGCs) with selective permeability and hydrophilicity were fabricated using poly(lactic‐co‐glycolic acid) (PLGA) and Pluronic F127 by a modified immersion precipitation method developed by our laboratory. The hydrophilized porous PLGA tubes as NGCs were fabricated by immersing a water‐saturated rod‐shape alginate hydrogel into PLGA/Pluronic F127 mixture solution (in tetraglycol). The PLGA/Pluronic F127 mixture was precipitated outside the alginate hydrogel rod by the diffusion of water from the hydrogel rod into PLGA/Pluronic F127 mixture solution. The inner diameter and wall thickness of tubes could be easily controlled by adjusting the diameter of alginate hydrogel rod and immersion time, respectively. It was observed that the tube wall has an asymmetric column‐shape porous structure. The inner surface of the tube had nano‐size pores (∼50 nm), which can effectively prevent from fibrous tissue infiltration but permeate nutrients and retain neurotrophic factors, while the outer surface had micro‐size pores (∼50 μm), which can allow vascular ingrowth for effective supply of nutrients and oxygen into the tube. From the investigations of mechanical property, water absorbabiliy, and model nutrient permeability of the tubes, the hydrophilized PLGA/F127 (3 wt %) tube seems to be a good candidate as a NGC for the effective permeation of nutrients as well as the good mechanical strength to maintain a stable support structure for the nerve regeneration. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Cyclin a but not cyclin D1 is essential for c‐myc‐modulated cell‐cycle progression
Authors: Qi Yitao , Tu Yiding , Yang Di , Chen Qian , Xiao Jun , Chen Yiqiang , Fu Juanling , Xiao Xilong , Zhou Zongcan
Published: September 2006

The proto‐oncogene c‐myc is a key player in cell‐cycle regulation and is deregulated in a broad range of human cancers and cell proliferation disorders. Here we reported that overexpression of c‐myc in human embryonic lung fibroblasts (HEL) that have low endogenous c‐myc enriched S phase cells with increased expression of cyclin D3, E, A, Cdk2, and Cdk4, and decreased expression of p21 and p27. To the opposite, using RNAi to downregulate c‐myc expression in A549 cells that have high endogenous c‐myc enriched G1 phase cells with decreased expression of cyclin D3, E, A, Cdk2, Cdk4, and increased expression of p21 and p27. We found that cyclin A expression was the most susceptive to changes in c‐myc levels and essential in c‐myc‐modulated cell cycle pathway via co‐transfection, however, cyclin D1 showed no change between treated and control groups in either HEL or A549 cells. Our results indicated that upregulation of c‐myc expression promotes cell cycling in HEL cells, whereas downregulation of c‐myc expression causes G1 phase arrest in A549 cells, and the c‐myc‐mediated cell‐cycle regulation pathway was dependent on cyclin A and involved cyclin D3, E, Cdk2, Cdk4, p21, and p27, but not cyclin D1. J. Cell. Physiol. 210: 63–71, 2007. © 2006 Wiley‐Liss, Inc.
Desensitization of GABABreceptor signaling by formation of protein complexes of GABAB2subunit with GRK4 or GRK5
Authors: Kanaide Masato , Uezono Yasuhito , Matsumoto Masanori , Hojo Minoru , Ando Yuko , Sudo Yuka , Sumikawa Koji , Taniyama Kohtaro
Published: September 2006

We investigated the role of G protein coupled‐receptor kinases (GRKs) in the desensitization of GABABreceptor‐mediated signaling usingXenopusoocytes and baby hamster kidney (BHK) cells. Baclofen elicited inward K+currents in oocytes coexpressing heterodimeric GABABreceptor, GABAB1asubunit (GB1aR) and GABAB2subunit (GB2R), together with G protein‐activated inwardly rectifying K+channels (GIRKs), in a concentration‐dependent manner. Repetitive application of baclofen to oocytes coexpressing GABABR and GIRKs did not change peak K+currents in the first and second responses, but the latter responses were significantly attenuated by coexpression of either GRK4 or GRK5 with attenuation efficacy of GRK4 > GRK5. Coexpression of other GRKs including GRK2, GRK3, and GRK6 had no effect on GABABreceptor‐mediated desensitization processes. In BHK cells coexpressing GRK4 fused to Venus (brighter variant of yellow fluorescent protein, GRK4‐Venus) with GB1aR and GB2R, GRK4‐Venus was expressed in the cytosol but was translocated to the plasma membranes by GABABR activation. In BHK cells coexpressing GRK4 fused to Cerulean (brighter variant of cyan fluorescent protein, GRK4‐Cerulean) with GB1aR and GB2R‐Venus, fluorescence resonance energy transfer (FRET) analysis demonstrated that GRK4‐Cerulean formed a protein complex with GB2R‐Venus. Immunoprecipitation and Western blot analysis confirmed GB2R‐GRK4 complex formation. GRK5 also formed a complex with GB2R on the plasma membranes as determined by FRET and Western blotting but not GRK2, GRK3, and GRK6. Our results indicate that GRK4 and GRK5 desensitize GABABreceptor‐mediated responses by forming protein complexes with GB2R subunit of GABABR at the plasma membranes. J. Cell. Physiol. 210: 237–245, 2007. © 2006 Wiley‐Liss, Inc.
Cytotoxicity and fibroblast properties during in vitro test of biphasic calcium phosphate/poly‐dl‐lactide‐co‐glycolide biocomposites and different phosphate materials
Authors: Ignjatović Nenad , Ninkov Petar , Kojić Vesna , Bokurov Miloš , Srdić Vladimir , Krnojelac Dijana , Selaković Srećko , Uskoković Dragan
Published: September 2006

Reconstruction of bone defects is one of the major therapeutic goals in various clinical fields. Bone replacement materials must satisfy a number of criteria. Biological criteria are biocompatibility, controlled biodegradability, and osteoconductive or even osteogenic potential. The material should have a three‐dimensional structure with an interconnected pore system so as to permit cell growth and transport of substances. The surface must permit cell adhesion and proliferation. Composite biomaterials have enormous potential for natural bone tissue reparation, filling and augmentation. Calcium hydroxyapatite/polymer composite biomaterials belong to this group of composites and, because of their osteoconductive and biocompatible properties, can be successfully implemented within bone tissue reparations. In this study, possible differences between BCP/DLPLG, pure BCP, and Bio‐Oss® materials were examined in vitro. During overnight incubations, fibroblast and fibroblast‐like cells (L929, MRC5) were able to adhere, spread, and remain viable on BCP, BCP/PLGA, and Bio‐Oss® discs, as was evidenced by using light‐ and LVSEM‐microscopy. Inhibiting influence over the cell growth is more pronounced in the cases of BCP usage on both cell lines—41.29% for L929 and 43.08% for MRC‐5 cells. MRC‐5 cells are, within the given experimental conditions, less sensitive on inhibiting effects for the materials BCP/PLGA and Bio‐Oss® (10.13% and 10.76%, respectively) than for the L929 cell lines (23.02% and 15.44%, respectively). Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
A composite gene delivery system consisting of polyethylenimine and an amphipathic peptide KALA
Authors: Min Sang‐Hyun , Lee Dong Chul , Lim Mi Jung , Park Hyun Sook , Kim Dong Min , Cho Cheong Weon , Yoon Do Young , Yeom Young Il
Published: September 2006

Background

Animal viruses such as enveloped virus carry multi‐functional proteins in the virion that can mediate more than two distinct steps of a gene delivery process during the transfer of viral genome into host cells. We tested if the aspects of the viral gene delivery mechanism could be mimicked by forming composite formulae from multi‐functional synthetic gene carriers having complementary action modes.

Methods

Polyethylenimine (PEI) was chosen as the component responsible for endosome escape and DNA condensation and KALA for cellular entry and DNA condensation. Compact DNA‐carrier particles consisting of the core part where DNA chains were tightly condensed by PEI and the outer layer lined with KALA were formulated, characterized and compared with monolithic cationic formulae in terms of gene delivery efficiency and mechanism.

Results

High‐level gene expression was observed when C2C12 cells were transfected with DNA that was first partially condensed with PEI and, then, fully with KALA. In these formulae KALA mediated enhanced cellular entry of DNA by facilitating endocytic vesicle formation, while PEI provided an effective endosomolytic capacity. An optimal PEI/KALA formula showed transfection efficiencies better than or comparable to the commercial cationic liposome in various cell types in culture and in vivo.

Conclusions

Gene delivery by combining the membrane‐active property of KALA with the endosomolytic activity of PEI can be more efficient than that by either of the properties alone. It appears that, in these formulae, the predominant role of KALA is to facilitate cellular entry of DNA by providing a fusogenic capability, rather than an endosomolytic activity. Copyright © 2006 John Wiley & Sons, Ltd.
Micronutrient composition of field‐grown dry bean and wheat inoculated with Azospirillum and Trichoderma
Authors: Öğüt Mehmet , Er Fatih
Published: September 2006

Micronutrient deficiency and malnutrition in humans are severe problems in many developing countries, particularly in areas with calcareous soils. There is almost no information on whether inoculation with plant growth–promoting Azospirillum and/or Trichoderma can help to reduce this problem by increasing the mineral concentration of the seeds. Field experiments were conducted in Tokat (Turkey) in 2001–2002 to determine whether inoculation with Azospirillum brasilense, Trichoderma harzianum, sole or in combination, and/or the application of P fertilizers can enhance micronutrient concentrations of field‐grown bean (Phaseolus vulgaris) and wheat (Triticum aestivum). In beans, Azospirillum inoculation combined with P fertilization significantly (p < 0.05) increased seed concentrations of Mn, Zn, and Cu, from 8.8, 22.6, and 7.0 mg kg–1 in the control to 10.3, 28.3, and 11.0 mg kg–1, respectively. Trichoderma inoculation alone significantly (p < 0.05) reduced the concentrations of Fe, Mn, Zn, and Cu and the cumulative plant uptake of Fe and Zn in 45‐day‐old bean plants. However, it significantly (p < 0.05) increased bean‐seed Cu content and accumulation. The double inoculation resulted in significantly (p < 0.05) higher micronutrient concentrations than Trichoderma inoculation alone in 45‐day‐old plants. In contrast to beans, the effects of microbial inoculations were less in wheat. However, dual inoculation significantly (p < 0.05) increased Zn content by 45% and Zn accumulation by 40% above the uninoculated control. Inoculation with plant growth–promoting microorganisms appears to be a promising strategy to combat micronutrient deficiencies.
Influence ofTithonia diversifoliaand triple superphosphate on dissolution and effectiveness of phosphate rock in acidic soil
Authors: Savini Isaac , Smithson Paul C. , Karanja Nancy K. , Yamasaki Hideo
Published: September 2006

An incubation and a pot experiment were conducted to evaluate the dissolution and agronomic effectiveness of a less reactive phosphate rock, Busumbu soft ore (BPR), in an Oxisol in Kenya. Resin (anion and anion + cation)‐extractable P and sequentially extracted P with 0.5MNaHCO3, 0.1MNaOH, and 1MHCl were analyzed. Dissolution was determined from the increase in anion resin (AER)–, NaHCO3‐, and NaOH‐extractable P in soil amended with PR compared with the control soil. Where P was applied, resin P significantly increased above the no‐P treatment. Busumbu‐PR solubility was low and did not increase significantly in 16 weeks. Anion + cation (ACER)‐extractable P was generally greater than AER‐P. The difference was greater for PR than for triple superphosphate (TSP). The ACER extraction may be a better estimate of plant P availability, particularly when poorly soluble P sources are used. Addition of P fertilizers alone or in combination withTithonia diversifolia(TSP, BPR, TSP +Tithonia, and BPR +Tithonia) increased the concentration of labile inorganic P pools (NaHCO3‐ and NaOH‐Pi). Cumulative evolved CO2was significantly correlated with cumulative N mineralized fromTithonia(r, 0.51,p< 0.05). Decrease in pH caused NH$ _4^+ $‐N accumulation while NO$ _3^- $‐N remained low whereTithoniawas incorporated at all sampling times. However, when pH was increased, NH$ _4^+ $‐N declined with a corresponding rise in NO$ _3^- $‐N.Tithoniasignificantly depressed soil exchangeable acidity relative to control with time. A significant increase (p< 0.05) was observed for P uptake but not dry‐mass production in maize where BPR was applied. The variations in yield and P uptake due to source and rates of application were statistically significant. At any given P rate, highest yields were obtained withTithoniaalone. Combination of Busumbu PR with TSP orTithoniadid not enhance the effectiveness of the PR. The poor dissolution and plant P uptake of BPR may be related to the high Fe content in the PR material.
Aluminum inhibits apoplastic flow of high–molecular weight solutes in root apices of Zea mays L.
Authors: Sivaguru Mayandi , Horst Walter J. , Eticha Dejene , Matsumoto Hideaki
Published: September 2006

Using an aluminum (Al)‐sensitive maize cultivar, we investigated the influence of Al on the apoplastic solute bypass flow and its relationship with Al‐induced (1 h, 50 μM) callose formation and root growth. We selected the fluorescent probes 8‐hydroxypyrene‐1,3,6‐trisulfonic acid, trisodium salt (MW 524) (HPTS) and dextran‐Texas Red (TR) conjugates (MW 3,000, 10,000, and 40,000) to monitor their apoplastic transport. Confocal laser–scanning microscopy (CLSM) analysis and spectrofluorometric quantification showed Al‐induced callose formation in peripheral root cells within 1 h. Pretreatment of plants with the callose synthesis inhibitor 2‐deoxy‐D‐glucose (DDG) reduced the callose formation by half. Uptake experiments with both HPTS and dextrans showed uniform dye distribution in control root apices. After Al treatment for 1 or 2 h, which inhibited root growth by 32% or 50%, respectively, the dyes accumulated in the epidermal and outer cortical cell layers, especially in the 1–2 mm apical root zone. Al treatment reduced the export of the dyes out of the apical 1 cm treatment zone. This was due to strong sorption of HPTS but not of dextrans by Al‐loaded cell walls. Aluminum treatment reduced loading into the xylem sap particularly of higher–molecular weight dextrans. Pretreatment of roots with DDG and presence of 50 mM mannitol during the Al treatment partially forestalled the inhibitory effect of Al on the dye transport, but only slightly reduced the Al‐induced growth inhibition. Exudation experiments revealed that xylem water flow remained unaffected by the Al treatment of the root tips. The results with dextran suggest that Al binding in cell walls of the root apex inhibits apoplastic bypass flow of higher–molecular weight solutes, which might contribute to Al‐induced inhibition of root growth.
Pleistocene subglacial tunnel valleys in the central North Sea basin: 3‐D morphology and evolution
Authors: Lonergan Lidia , Maidment Susannah C. R. , Collier Jenny S.
Published: September 2006

Four phases of cross‐cutting tunnel valleys imaged on 3‐D seismic datasets are mapped within the Middle–Late Pleistocene succession of the central North Sea basin (Witch Ground area). In plan the tunnel valleys form complex anastomosing networks, with tributary valleys joining main valleys at high angles. The valleys have widths ranging from 250 to 2300 m, and base to shoulder relief varying between 30 and 155 m, with irregular long‐axis profiles characteristic of erosion by water driven by glaciostatic pressures. The youngest phase of tunnel valleys are smaller and have a thinner infill than the older generations. The fill of the larger valleys comprises three seismic facies, the lowermost of which has high amplitudes and is discontinuous. The middle facies consists of wedge‐shaped packages of low‐angle dipping reflectors and is overlain by a facies characterised by sub‐horizontal reflectors, which onlap the valley margins. The seismic character, and comparison with lithologies identified in other northwest European Pleistocene tunnel valleys both onshore and offshore, suggests that the lower two seismic facies are most likely sand and gravel‐dominated, while the uppermost facies consists of glaciolacustrine and marine muds. The 3‐D morphology of the valley margins combined with the geometry of the infill packages suggest that episodic discharge of subglacial meltwater was responsible for incising the valleys and depositing at least some of the infill. Proglacial glaciofluvial deposits are inferred to account for some of the fill overlying the subglacial deposits. Glaciolacustrine and marine muds filled remaining valley topography as the ice sheet retreated. The preserved valley margins are shown to be time‐transgressive erosion surfaces that record changes in geometry of the tunnel valley system as it evolved through time, implying that valleys associated with each ice‐sheet advance/retreat cycle were dynamic and probably long‐lived. Within the constraints of the existing stratigraphy the oldest tunnel valleys in the Witch Ground area of the central North Sea are most likely to be Marine Isotope Stage (MIS) 12 (Elsterian, ca. 470 ka) in age and the youngest pre‐MIS 5e (last interglacial, ca. 120 ka). If each tunnel valley phase was formed during the retreat of a major ice sheet then four glaciations with ice coverage of the central North Sea are recorded in the pre‐Weichselian, Middle–Late Pleistocene stratigraphy. Copyright © 2006 John Wiley & Sons, Ltd.
Cover Picture: Macromol. Biosci. 9/2006
Authors: Loizou Elena , Weisser Jaime T. , Dundigalla Avinash , Porcar Lionel , Schmidt Gudrun , Wilker Jonathan J.
Published: September 2006

Cover: The structure and properties of a cross‐ linked gelatinuous protein extracted from marine mussels are examined both before and after cross‐linking with iron. Morphological and materials properties changes, such as stiffness, are brought about by partial and imperfect chemical cross‐linking. Further details can be found in the article by E. Loizou, J. T. Weisser, A. Dundigalla, L. Porcar, G. Schmidt,* and J. J. Wilker* on 711.
Network Formation in Nitroxide‐Mediated Radical Copolymerization of Styrene and Divinylbenzene in Miniemulsion
Authors: Nur Alam Md. , Zetterlund Per B. , Okubo Masayoshi
Published: September 2006

Summary: Polymer network formation in controlled/living radical crosslinking copolymerization of S/DVB initiated by a poly(S)‐TEMPO macroinitiator in aqueous miniemulsion at 125 °C is investigated. The crosslinking proceeded differently in miniemulsion (heterogeneous systems) and in bulk/solution (homogeneous systems), with markedly lower apparent pendant reactivity in miniemulsion. The relative rate of DVB consumption was lower in miniemulsion than in bulk/solution. It is proposed that the interface between the particle (monomer droplet at time = 0) and the aqueous phase may play an important role during the crosslinking process. The presence of tetradecane as a hydrophobe in the monomer droplets strongly influenced both the pendant reactivity and the molecular weight distributions in miniemulsion, whereas only small effects were observed in the corresponding bulk/solution polymerizations. It is believed that this is related to previous results of the hydrophobe promoting migration of poly(DVB) to the interface of toluene droplets in aqueous emulsion. The results suggest novel approaches towards control of polymer network development in crosslinking radical polymerizations.

Total (filled symbols) and intermolecular (open symbols) pendant conversions for TEMPO‐mediated radical copolymerization of S/DVB.

magnified image

Total (filled symbols) and intermolecular (open symbols) pendant conversions for TEMPO‐mediated radical copolymerization of S/DVB.
Problematic gambling on dopamine agonists: Not such a rarity
Authors: Grosset Katherine A. , Macphee Graeme , Pal Guru , Stewart David , Watt Andrew , Davie Jim , Grosset D.G.
Published: September 2006

Excessive gambling is recognized with dopamine agonist therapy, but the prevalence is unknown. We assessed the prevalence of excess gambling by specific prospective enquiry in Parkinson's disease patients attending six West Scotland movement disorder clinics. Of 388 patients taking anti‐Parkinson medication, 17 (4.4%) developed pathological gambling, all of whom were prescribed dopamine agonists. Thus, 8% of patients taking dopamine agonists had pathological gambling. Pathological gambling is not uncommon, and patients should be made aware of this potential adverse effect. © 2006 Movement Disorder Society
Effect of a concurrent task on driving performance in people with Parkinson's disease
Authors: Stolwyk Rene J. , Triggs Tom J. , Charlton Judith L. , Moss Simon , Iansek Robert , Bradshaw John L.
Published: September 2006

Numerous studies previously have reported reduced driving performance in people with Parkinson's disease (PD). Few studies to date, however, have examined how specific cognitive difficulties associated with PD impact on specific aspects of driving performance in this population. In this study, the impact of a concurrent task on driving performance was examined. A simulator was used to measure the driving behavior of 18 current drivers with PD and 18 matched controls. The presence of a concurrent task was manipulated between conditions. Results showed that, although groups were similarly affected by the concurrent task on most driving measures, participants with PD were disproportionately affected on operational level driving behavior. It also appears that participants with PD sacrificed concurrent task performance to maintain driving performance. These results further support the hypothesis that cognitive difficulties associated with PD compromise driving performance in this population, even in the mild to moderate stages of the disease. © 2006 Movement Disorder Society
Punding and dyskinesias
Authors: Silveira‐Moriyama Laura , Evans Andrew H. , Katzenschlager Regina , Lees Andrew J.
Published: September 2006

The presence of punding in Parkinson's disease (PD) has been associated with inappropriate excessive use of dopaminergic medication but its relation to the severity of dyskinesias is not known. Through the use of clinical examination and medical chart review, the presence of punding and the severity of interdose dyskinesias were evaluated by two different observers. Punding was associated with more frequent interventions to reduce dyskinesias and with greater dyskinesia severity. We suggest the neural systems mediating the expression of dyskinesias and punding might overlap and that punding should be looked for systematically in PD patients presenting with disabling severe dyskinesias. © 2006 Movement Disorder Society
Early piribedil monotherapy of Parkinson's disease: A planned seven‐month report of the REGAIN study
Authors: Rascol Olivier , Dubois Bruno , Caldas Alexandre Castro , Senn Stephen , Del Signore Susanna , Lees Andrew
Published: September 2006

Piribedil is a D2 dopamine agonist, which has been shown to improve symptoms of Parkinson's disease (PD) when combined with L‐dopa. The objective of this study was to compare the efficacy of piribedil monotherapy to placebo in patients with early PD over a 7‐month period. Four hundred and five early PD patients were randomized (double‐blind) to piribedil (150–300 mg/day) or placebo. L‐dopa open‐label supplementation was permitted. Unified Parkinson Disease Rating Scale part III (UPDRS III) score as the last observation on monotherapy over 7 months was the primary outcome measure. Secondary outcomes were proportion of responders (UPDRS III improvement > 30%), patients remaining on monotherapy after 7 months, UPDRS III subscores, and UPDRS II. UPDRS III improved on piribedil (−4.9 points) versus a worsening on placebo (2.6 points; estimated effect = 7.26 points; 95% CI = 5.38–9.14; P < 0.0001). The proportion of responders was significantly higher for piribedil (42%) than for placebo (14%) (OR = 4.69; 95% CI = 2.82–7.80; P < 0.001). Piribedil significantly improved several UPDRS III subscores. UPDRS II improved on piribedil by −1.2 points, while it deteriorated by 1.5 points on placebo (estimated effect = 2.71; 95% CI = 1.8–3.62; P < 0.0001). The proportion of patients remaining on monotherapy after 7 months was greater in the piribedil group (OR = 3.72; 95% CI = 2.26–6.11; P < 0.001). Safety was consistent with that reported for other dopamine agonists, gastrointestinal side effects being the most common (22% of patients in piribedil group vs. 14% on placebo). Piribedil is effective and safe as early PD therapy. © 2006 Movement Disorder Society
The ancient inhabitants of Jebel Moya redux: measures of population affinity based on dental morphology
Authors: Irish J. D. , Konigsberg L.
Published: September 2006

This paper reexamines some of the methods and craniometric findings in the classic volumeThe Ancient Inhabitants of Jebel Moya (Sudan)(1955) by Mukherjee, Rao & Trevor, in light of recent archaeological data and relative to a new dental morphological study. Archaeological evidence characterises these inhabitants as having been heavily influenced by outside sources; yet they managed to establish and maintain their own distinctive culture as seen in the site features and surviving artefact collections. The dental study, modelled after the original craniometric‐based investigation and using the same or similar comparative samples, detected complementary indications of outside biological influence. In the study, up to 36 dental traits were recorded in a total of 19 African samples. The most influential traits in driving inter‐sample variation were then identified, and phenetic affinities were calculated using the Mahalanobis D2statistic for non‐metric traits. If phenetic similarity provides an estimate of genetic relatedness, these affinities, like the original craniometric findings, suggest that the Jebel Moyans exhibited a mosaic of features that are reminiscent of, yet distinct from, both sub‐Saharan and North African peoples. Together, these different lines of evidence correspond to portray the Jebel Moya populace as a uniform, although distinct, biocultural amalgam. Copyright © 2006 John Wiley & Sons, Ltd.
Influence of the Gas Phase on the Water Vapor Barrier Properties of SiOx Films Deposited from RF and Dual‐Mode Plasmas
Authors: Sonnenfeld Axel , Bieder Andrea , Rudolf von Rohr Philipp
Published: September 2006

Summary: The influence of different gas phase species and the positive ion density on the water vapor barrier performance of SiOx thin films is investigated in this study. A reactor equipped with a remote 2.45 GHz slot antenna plasma source and a 13.56 MHz‐biased substrate holder was used to deposit films from gas mixtures of oxygen and HMDSO. Besides determining the WVTR of films, different excited gas phase species were monitored by means of OES and the positive ion density in pure oxygen was measured by LP. The dependencies of the positive ion density and of the actinometric trends of species on the oxygen flow rate as well as on the power input by RF and MW source were investigated. Both gas‐phase diagnosis techniques reveal a higher excitation of the gas‐phase in dual mode than in pure RF plasma. Production of atomic species seems to be enhanced under such conditions, which however leads to enhanced oxidation of HMDSO and its fragments by atomic oxygen. Hence, at oxygen flow rates above 200 sccm, enough atomic oxygen seems to be obtained so that the film growth mechanism is dominated by homogeneous combustion reactions, overriding the beneficial effect of the substrate self bias. Thus, a complete loss of the water vapor diffusion barrier is observed. Apart from these defective deposits, typical films revealed low WTVR for the entire variation range in RF mode and below 200 sccm of oxygen flow also in dual mode. Here, a decrease of the WVTR with RF power (i.e. DC self bias) and the oxygen flow rate was obtained, while WVTR could be reduced to 0.1 g · m−2 · d−1 corresponding to a barrier improvement by a factor of 150 if compared to uncoated substrate polymers.

magnified image
Pollen population, viscosity and density of locally produced honey
Authors: Ayodele MS , Folarin OM , Oluwalana SA
Published: September 2006

Eight samples of honey, purchased locally, all contained pollen grains of different sizes and shapes. There was a correlation between the pollen population and pollen size, but not between the population and either density or viscosity of the honey. Copyright © 2006 John Wiley & Sons, Ltd
G2 checkpoint‐dependent DNA repair and its response to catalase in Down syndrome and control lymphocyte cultures
Authors: Pincheira Juana , Romero Pablo , Marcelain Katherine , Salazar Lorena , de la Torre Consuelo
Published: September 2006

The amount of DNA lesions repaired in G2 and also G2 timing are controlled by the DNA damage‐dependent checkpoint. Down syndrome (DS) lymphocytes showed twice as much constitutive DNA damage in G2 than control ones, when recording it as chromosomal aberrations in metaphase, after caffeine‐induced checkpoint abrogation. During G2, DS lymphocytes repaired 1.5 times more DNA lesions than control ones. However the DS cells displayed a decreased threshold for checkpoint adaptation, as the spontaneous override of the G2 to mitosis transition block induced by the checkpoint took place in the DS cells when they had three times more DNA lesions than controls. Catalase addition to cultures scavenges hydrogen peroxide diffused from cells, resulting in subsequent intracellular depletion (Antunes and Cadenas, 2000). The intracellular H2O2 level seemed to regulate the G2 checkpoint. Thus, in controls, H2O2 depletion (induced by 3.2–50 μg/mL catalase) prevented its functioning: chromosomal damage increased while G2 shortened. Conversely, in the DS lymphocytes, 12.5 μg/mL catalase lengthened G2 and decreased chromosomal damage, in spite that the amount of DNA repaired in G2 was half of that repaired in the catalase‐free DS lymphocytes.
Ornithine decarboxylase overexpression enhances ERK and p38 phosphorylation and matrix metalloproteinase‐2 expression
Authors: Nemoto Takahiro , Kubota Shunichiro
Published: September 2006

In the present study, we investigated the relationship between ornithine decarboxylase, MAP kinase, and MMP‐2 expression in vitro. Overexpression of ornithine decarboxylase cDNA induced MMP‐2 expression both at mRNA and protein levels. Promoter analysis and gel shift assay showed that p53 and Ets‐1 were involved in MMP‐2 expression in ornithine decarboxylase overexpressing transfectants. Erk and p38 MAP kinase were significantly activated. Using specific inhibitors of MEK and p38, we clarified that MMP‐2 expression was induced via both Erk and p38 MAP kinase signaling pathways. This is the first report showing the existence of a causal relationship between ornithine decarboxylase expression, Erk and p38 MAP kinase activation, and MMP‐2 expression.
A portfolio balance approach to the Canadian–U.S. exchange rate
Authors: Cushman David O.
Published: September 2006

An empirical portfolio balance model based on Branson and Henderson [Branson, W. H., & Henderson, D. W. (1985). The specification and influence of assets markets. In: Jones R. W., Kenen, P. B. (Eds.), Handbook of International Economics, Volume 2, Elsevier, Amsterdam] is specified for the Canadian–U.S. exchange rate over the floating exchange rate period. Empirical implementation reveals two cointegrating vectors that closely, although not perfectly, match the home and foreign asset demands of the theoretical model. Furthermore, the exchange rate is important in the error correction process. Finally, although the significance is quantitatively and statistically modest, a simplified version of the empirical model resulting from general‐to‐specific procedures is able to beat a random walk at some out‐of‐sample forecast horizons.
Suicide in the Greek Penal System and the Problem of Various Limitations in Relevant Studies
Authors: Themeli Olga
Published: September 2006

Suicides in prison are not merely self-destructive acts or a “cry for help.” They reflect the inherent need for freedom and the repercussions of imprisonment. SPACE statistics on suicides in prison reveal a rate above 10 per 10,000 in 10 European countries, 4 of which have a rate above 20. Greek data do not appear in all SPACE statistics. This fact has stimulated the present paper. Unpublished data obtained from the Greek Ministry of Justice reveal that Greece belongs to the group of countries with a rate below 10 in 1995 (the year of SPACE statistics). However, the suicide rates fluctuated widely in Greece from a low rate of 3.2 per 10,000 prisoners (convicted, on remand, or hospitalized) in 1982 to the incredibly high rate of nearly 40 in the year 1979 (11 suicides, 10 of which occurred in prison hospitals). A review of the literature indicates that various limitations mentioned in relevant studies lie in the unreliability of data (doubts about the validity of official statistics, missing data in archives, missing files on the victims, suicide in juvenile institutions not always recorded separately, etc.). The research emphasizes the importance of improving suicide statistics (recording, clearing up the incidents of deaths that are recorded without specification of cause, etc.) in order to plan and enforce suicide prevention and intervention strategies that seem to “work” in a particular milieu and are not debatable (e.g., the use of “suicide proof” cells).
Intrinsic elasticity of a textured transversely isotropic muscovite aggregate: Comparisons to the seismic anisotropy of schists and shales
Authors: Cholach Pavlo Y. , Schmitt Douglas R.
Published: September 2006

The anisotropic properties of phyllosilicate rocks are investigated through the modeling of the pore‐free “intrinsic” elasticity of a textured muscovite aggregate. The elastic constants were calculated for textures, as defined using orientation distribution functions (ODFs), ranging from perfectly aligned to completely random. The ODFs were described using a Gaussian distribution, the width of which is controlled by the standard deviation of the orientations of the crystal c axis with respect to the sample foliation plane under the assumption that the sample has hexagonal (transversely isotropic) symmetry. The values were obtained using the widely used Voigt‐Reuss‐Hill averaging techniques as well as the geometric mean average (GMA). The GMA is more physically meaningful in that it requires that the elastic constants determined in either the stiffness or the compliance domains be invertible. Comparisons between these different averages indicate that, strictly, the Voigt and Reuss values do not necessarily provide the limiting bounds as is expected for the isotropic case. Despite this, some characteristics of the elastic wave P wave anisotropy are only weakly dependent on the averaging procedure employed. The calculated elastic constants are converted to the anisotropic ɛ, δ, and γ parameters in order to allow for comparison to existing measurements in the literature. However, these “intrinsic” results are not intended to provide a measure of the properties of phyllites per se but to provide a reference against which more sophisticated models that incorporate porosity, layering, and composition may be constructed.
Impact of an unstressed canopy conductance on the Bouchet‐Morton complementary relationship
Authors: Pettijohn Justin C. , Salvucci Guido D.
Published: September 2006

Indirect methods of quantifying evapotranspiration (λEa) are sought since regional estimations of λEa require prohibitive instrumentation or highly parameterized and data‐intensive land surface models (e.g., involving temporally and spatially varying soil moisture, soil hydraulic properties, and vegetation properties). Complementary relationship (CR) models, based on Bouchet's hypothesis, are one such method of estimating λEa from routinely measured meteorological variables. Bouchet's CR states that given a change in regional surface moisture availability (MA), changes in λEa are reflected in changes in potential evapotranspiration (λEp), such that λEa + λEp = 2λE0, where λE0 is an assumed equilibrium condition at which λEa = λEp = λE0 given sufficiently large MA. Whereas λEp conceptually includes a transpiration component, the treatment of vegetation in existing CR applications varies from neglecting it to indirectly accounting for it through recalibration of Penman's empirical wind function. We utilize the First International Land Surface Climatology Field Experiment (FIFE) data set to demonstrate that inclusion of a maximum (i.e., unstressed) canopy conductance (gc,max) in a Penman equation with stability‐corrected atmospheric conductance (i.e., replacing the Penman equation with an unstressed Penman–Monteith equation) significantly improves both CR convergence and symmetry. Inclusion of gc,max results in more accurate λEa estimates than are found with the Penman equation (using either Monin–Obukhov atmospheric conductance or using empirical wind functions in the literature). The proposed method also performs better than the 1992 advection‐aridity CR method, modified to include atmospheric stability effects, which attributes noncomplementarity to horizontal advection and corrects for it by adjusting λE0 by the magnitude of the potential sensible heat flux (∣Hp∣), found from the surface energy balance of the λEp calculation. In the proposed method a similar energy balance adjustment occurs naturally because the finite canopy conductance causes an increase of surface temperature and sensible heat flux in the λEp energy balance calculation. The proposed method is consistent with CR explanations that rely on feedbacks with the boundary layer vapor pressure deficit since the impact of such changes on both λEp and λEa would be modulated by stomatal conductance.
Anomalous pelagic nekton abundance, distribution, and apparent recruitment in the northern California Current in 2004 and 2005
Authors: Brodeur Richard D. , Ralston Stephen , Emmett Robert L. , Trudel Marc , Auth Toby D. , Phillips A. Jason
Published: September 2006

Although the California Current has undergone substantial environmental shifts in the past few decades, the summer of 2005 exhibited highly anomalous conditions relative to all previous recorded summers in terms of late initiation of upwelling and the resulting elevated surface temperatures and depressed productivity through July. The response of pelagic nekton to these anomalous conditions was widespread and included onshore and poleward displacement of taxa to new geographic areas, population changes within the normal range, and reduced productivity of early life stages based on larval and juvenile surveys. Some nekton exhibited anomalous distributions in 2004. Many ecologically important species were affected. The response of the nektonic community off California was greater than during El Niño conditions.
Weekend effect in diurnal temperature range in China: Opposite signals between winter and summer
Authors: Gong Dao‐Yi , Guo Dong , Ho Chang‐Hoi
Published: September 2006

Intense human activity can impact weather and climate in many ways. One possible important consequence is the weekly cycle (so‐called weekend effect) in the diurnal temperature range (DTR). The weekend effect is defined as the average DTR for Saturday through Monday minus the average DTR for Wednesday through Friday. In the present study, the weekend effect in the DTR over east China combined with station observations of maximum and minimum temperatures, relative humidity, and total solar irradiance for the period 1955–2000 was analyzed. Results show that the weekend effect in the DTR has the opposite signal between winter (December, January, and February) and summer (June, July, and August). Wintertime DTR tends to have a positive weekend effect (i.e., larger DTR in weekend days compared to weekdays), in association with increased maximum temperature and total irradiance but decreased relative humidity. While summertime DTR displays a much stronger and significantly negative weekend effect (i.e., smaller DTR in weekend days), in association with decreased maximum temperature and total solar irradiance but increased relative humidity and a greater number of rainy days. This study indicates that the DTR difference between weekend and weekdays is predominantly related to weekly changes in the maximum temperature. The weekend effect in the DTR and maximum temperature is also found in the Reanalysis 2 data. The weekend effect in winter is supported by an analogous holiday (Spring Festival) effect. Since the late 1970s, the weekend effect has been enhanced in both winter and summer, concurrent with rapid development and enhanced human activity in China. The direct and indirect effects of human‐related aerosols on radiation, cloud, precipitation, and so on, might play an important role in generating the opposite signal in the weekend effect for different seasons. During a dry winter, the reduction of aerosol concentrations may overwhelmingly impact on the DTR through a direct effect, i.e., by increasing total solar irradiance near the surface and raising the daytime temperature and maximum temperature and lowering relative humidity. By contrast, in summer the indirect effect of aerosols, i.e., reduction in precipitation efficiency caused by more numerous and smaller cloud droplets, would largely be responsible for the increased numbers of rainy days, the reduction of the total solar irradiance, and the lowering of the maximum temperature and DTR.
Identification of Antarctic ablation areas using a regional atmospheric climate model
Authors: van den Broeke Michiel , van de Berg Willem Jan , van Meijgaard Erik , Reijmer Carleen
Published: September 2006

The occurrence of Antarctic ablation areas in Dronning Maud Land, the Lambert Glacier Basin, Victoria Land, the Transantarctic Mountains and the Antarctic Peninsula is realistically predicted by the regional atmospheric climate model RACMO2/ANT, with snowdrift‐related processes calculated offline. Antarctic ablation areas are characterized by a low solid precipitation flux in combination with strong sublimation, snowdrift erosion and/or melt. The strong interaction between atmospheric circulation and topography plays a decisive role in the precipitation distribution and hence that of ablation areas. Three types of Antarctic ablation areas can be distinguished, all occurring in dry regions: Type 1 is the erosion‐driven ablation area, caused by 1‐D and/or 2‐D divergence in the katabatic wind field at high elevations (2000–3200 m asl). Type 2 is the sublimation‐driven ablation area. This type occurs at lower elevations (<2000 m) preferably at the foot of steep topographic barriers, where temperature and wind speed are high and relative humidity low. Type 3 represents the melt‐driven ablation area, occurring in the northern Antarctic Peninsula. Combinations of types 1/2 and 2/3 are possible. Over the period considered here (1980–2004), no significant trend is found in the total area covered by Antarctic ablation areas, which equals about 2% of the total ice sheet surface (including ice shelves).
Operant matching is a generic outcome of synaptic plasticity based on the covariance between reward and neural activity
Authors: Loewenstein Yonatan , Seung H. Sebastian
Published: September 2006

The probability of choosing an alternative in a long sequence of repeated choices is proportional to the total reward derived from that alternative, a phenomenon known as Herrnstein's matching law. This behavior is remarkably conserved across species and experimental conditions, but its underlying neural mechanisms still are unknown. Here, we propose a neural explanation of this empirical law of behavior. We hypothesize that there are forms of synaptic plasticity driven by the covariance between reward and neural activity and prove mathematically that matching is a generic outcome of such plasticity. Two hypothetical types of synaptic plasticity, embedded in decision-making neural network models, are shown to yield matching behavior in numerical simulations, in accord with our general theorem. We show how this class of models can be tested experimentally by making reward not only contingent on the choices of the subject but also directly contingent on fluctuations in neural activity. Maximization is shown to be a generic outcome of synaptic plasticity driven by the sum of the covariances between reward and all past neural activities.