bluuebunny/crossref_metadata_2025 huggingface dataset:
Compression Molding of Aspherical Glass Lenses–A Combined Experimental and Numerical Analysis
Authors: Yi Allen Y. , Jain Anurag
Published: March 2005

Compression molding of glass aspherical lenses has become a viable manufacturing process for precision optics. The widespread use of this process has been hampered by the lack of its fundamental understanding. This research is a part of the ongoing effort to understand some of the issues related to the process. Simple lens molding experiments were performed on a commercial precision lens molding machine. A finite element method (FEM) program was used to create a simple numerical model and analyze the molding process. Experimental results show that this process is capable of producing precision optical components. A comparison of the experimental results with the predicted results indicates that with a more sophisticated numerical model, it is possible to use FEM as a tool for process analysis.
Effect of Crystallization on the Stress Required for Constrained Sintering of CaO–B2O3–SiO2 Glass–Ceramics
Authors: Lei Cheng‐Dao , Jean Jau‐Ho
Published: March 2005

The effect of crystallization on the stress required for complete constrained sintering of a low‐temperature cofirable CaO–B2O3–SiO2 glass–ceramics has been investigated under uniaxial constant and cyclic loading. As the formation of crystalline phase of wollastonite (CaSiO3) increases, the uniaxial viscosity of the porous glass–ceramics during firing increases. Moreover, the required uniaxial stress to have complete constrained sintering, i.e., zero strain or strain rate at the perpendicular directions, is in the range of 80–180 kPa, which shows no significant dependence on heating rate and firing temperature. The measured data of required stress are close to those calculated using the viscous analogy for the constitutive relationship of a porous sintering compact.
Kontrollierte schichtweise Abtragung anogenitaler Warzen mittels Argon‐Plasma‐Koagulation
Authors: Weyandt Gerhard H. , Benoit Sandrine , Becker Jürgen C. , Bröcker Eva‐Bettina , Hamm Henning
Published: March 2005

Hintergrund: Bei ausgedehntem anogenitalen Warzenbefall werden nach den Leitlinien der Deutschen STD‐Gesellschaft als mögliche Behandlungsformen mit vergleichbaren Rezidivraten die Kryotherapie, exzidierende Verfahren, die Elektrodesikkation, CO2‐ und Nd:YAG‐Laserabtragung empfohlen. Bei diesen Verfahren besteht ein unterschiedlich hohes Risiko von Blutungen, Freisetzung potentiell infektionsfähiger Viruspartikel in die Raumluft, tiefer thermischer Destruktion, langer Wundheilungszeit und Vernarbung.

Methode: Mit der Argon‐Plasma‐Koagulation werden anogenitale Warzen kontrolliert schichtweise abgetragen. Dabei wird Hochfrequenzstrom kontaktlos durch ionisiertes Argon auf die Gewebeoberfläche übertragen, wodurch eine oberflächliche Koagulation mit nahezu konstanter Eindringtiefe erreicht wird.

Ergebnisse: Wir behandelten in der Zeit von Januar 2001 bis März 2003 54 Patienten mit ausgedehntem genitalen, analen oder kombinierten Befall von Warzen. Nach einmaliger Therapie waren 66 % der Patienten bis zum Abschluß der Kontrolluntersuchungen nach 4 Monaten erscheinungsfrei. Rezidive wurden bei 13 Patienten (24 %) nach 4 Wochen und bei weiteren 5 Patienten (9 %) zu einem späteren Zeitpunkt beobachtet. Nach weiteren Abtragungen sowie ggf. zusätzlicher Behandlung mit Imiquimod‐Creme (n = 9, 17 %) waren alle Patienten erscheinungsfrei.

Schlußfolgerung: Die Behandlung mittels Argon‐Plasma‐Koagulation stellt im Vergleich zu den anderen Verfahren eine besser kontrollierbare, risikoarme und rasch durchführbare Methode der Behandlung anogenitaler Warzen dar. In Abhängigkeit vom Befallsmuster und individuellen Risikofaktoren erscheint im Einzelfall eine Nachbehandlung mit Imiquimod‐Creme sinnvoll.
Childhood granulomatous periorificial dermatitis: a controversial disease
Authors: Zalaudek Iris , Stefani Alessandro Di , Ferrara Gerardo , Argenziano Giuseppe
Published: March 2005

The etiology, diagnosis and treatment of childhood granulomatous periorificial dermatitis (GPD) are highly controversial. Some authors underline the similarities between GPD and perioral dermatitis and consider both as part of a spectrum while other authors regard GPD as a distinctive condition. Clinically GPD is a papulo‐pustular periorificial disease of the face which histopathologically shows a granulomatous perifollicular infiltrate. Because of its granulomatous pattern, GPD also has been related to cutaneous sarcoidosis. The clinical course is benign and self‐limited. Topical steroids are regarded as either the main cause or a worsening factor. While topical treatment is occasionally effective, systemic antibiotic therapy of GPD is usually recommended. We report a “typical” case of GPD and review the literature to discuss the difficulties in its diagnosis and treatment.
Modulatory effects of low‐ and high‐frequency repetitive transcranial magnetic stimulation on visual cortex of healthy subjects undergoing light deprivation
Authors: Fierro Brigida , Brighina Filippo , Vitello Gaetano , Piazza Aurelio , Scalia Simona , Giglia Giuseppe , Daniele Ornella , Pascual‐Leone Alvaro
Published: March 2005

The aim of the present study was to explore further the effects of light deprivation (LD) on visual cortex excitability. Healthy subjects reporting reliable induction of phosphenes by occipital transcranial magnetic stimulation (TMS) underwent 60 min of complete LD. Phosphene threshold (PT) was measured before (T0), after 45 min (T1) and 60 min (T2) of LD, and then every 10 min after light re‐exposure until recovery to T0 values. Repetitive TMS (rTMS) (at 1 or 10 Hz) was applied in separate sessions during the last 15 min of LD. PTs significantly decreased after 45 min of LD. rTMS differentially modified the effects of 60 min LD on PTs depending on stimulation frequency. One hertz rTMS did not change the decreasing of PT values as observed in baseline condition, but significantly prolonged the time to recover T0 PT values after light re‐exposure. By contrast, 10 Hz rTMS significantly increased PT and the time to recover T0 PT values after light re‐exposure was shortened. The results of this study show that the modulatory effects of different rTMS frequencies on visual cortex critically depend on the pre‐existing excitability state of inhibitory and facilitatory circuits, and provide novel insights into the neurophysiological changes that take place in the visual cortex following functional visual deafferentation.
Protein kinase A‐dependent enhanced NMDA receptor function in pain‐related synaptic plasticity in rat amygdala neurones
Authors: Bird Gary C. , Lash L. Leanne , Han Jeong S. , Zou Xiaoju , Willis William D. , Neugebauer Volker
Published: March 2005

Mechanisms of pain‐related plasticity in the amygdala, a key player in emotionality, were studied at the cellular and molecular levels in a model of arthritic pain. The influence of the arthritis pain state induced in vivo on synaptic transmission and N‐methyl‐d‐aspartate (NMDA) receptor function was examined in vitro using whole‐cell voltage‐clamp recordings of neurones in the latero‐capsular part of the central nucleus of the amygdala (CeA), which is now defined as the ‘nociceptive amygdala’. Synaptic transmission was evoked by electrical stimulation of afferents from the pontine parabrachial area (part of the spino‐parabrachio‐amygdaloid pain pathway) in brain slices from control rats and from arthritic rats. This study shows that pain‐related synaptic plasticity is accompanied by protein kinase A (PKA)‐mediated enhanced NMDA‐receptor function and increased phosphorylation of NMDA‐receptor 1 (NR1) subunits. Synaptic plasticity in the arthritis pain model, but not normal synaptic transmission in control neurones, was inhibited by a selective NMDA receptor antagonist. Accordingly, an NMDA receptor‐mediated synaptic component was recorded in neurones from arthritic animals, but not in control neurones, and was blocked by inhibition of PKA but not protein kinase C (PKC). Exogenous NMDA evoked a larger inward current in neurones from arthritic animals than in control neurones, indicating a postsynaptic effect. Paired‐pulse facilitation, a measure of presynaptic mechanisms, was not affected by an NMDA‐receptor antagonist. Increased levels of phosphorylated NR1 protein, but not of total NR1, were measured in the CeA of arthritic rats compared to controls. Our results suggest that pain‐related synaptic plasticity in the amygdala involves a critical switch of postsynaptic NMDA receptor function through PKA‐dependent NR1 phosphorylation.
Ancient Mars: Wet in Many Places
Authors: Paige David A.
Published: March 2005

New results from the Mars Express Orbiter mission reveal multiple deposits of minerals formed in the presence of liquid water. They reinforce the conclusion that ancient Mars was warmer and wetter than it is today, and increase the number of promising localities to search for evidence of past life.
Further Applications of Cyclic Voltammetry with Spherical Electrodes
Authors: Moreno Marién M. , Molina Ángela
Published: March 2005

In this work we show analytical and easily manageable explicit equations corresponding to the application of any multipulse potential sequence to planar, spherical and cylindrical electrodes. We apply these expressions to study reversible charge transfer electrode processes in cyclic voltammetry with spherical electrodes, by considering that both members of the redox pair are initially present in solution, and showing that a conventional symmetrical sweep can be used under these conditions. These expressions allow study in depth fundamental aspects of cyclic voltammetry with spherical electrodes. Thus, in the cyclic voltammograms obtained for simple reversible processes with conventional spherical electrodes at different sweep rates, characteristic common points of non zero current (isopoints) appear from which unknown thermodynamic parameters of these systems can be easily determined. From these equations it can be predicted and demonstrated that there are important analogies of the I/E behavior between a simple reversible charge transfer reaction and a first-order catalytic process when any single or multipulse voltammetric transient techniques are applied.
Synthetic Utility of 2-Benzylidene-1,2,3,4-tetrahydrocarbazol-1-ones. A Facile Syntheses of Pyrano[2,3-a]carbazoles, Pyrido[2,3-a]carbazoles and Pyridazino[3,4-a]carbazoles
Authors: Danish Isravel Antony , Rajendra Prasad Karnam Jayarampillai
Published: March 2005

2-Benzylidene-1,2,3,4-tetrahydrocarbazol-1-ones 1, synthons easily accessible from the corresponding 1,2,3,4-tetrahydrocarbazol-1-ones, were utilized in the synthesis of fused carbazoles. In accordance, the reaction of 1 with malononitrile yielded pyrano[2,3-a]carbazoles 2a and 2d or pyrido[2,3-a]carbazoles 2b, 2c and 2e. The reaction of 1 with thiocarbohydrazide or thiosemicarbazide under basic conditions afforded pyridazino[3,4-a]carbazoles 3 or thiol substituted pyridazino[3,4-a]carbazoles 4, respectively, in good yields. The formation of the hitherto unknown compounds was well supported by plausible mechanisms. The products formed were characterized by IR, 1H NMR, 13C NMR, mass spectral methods and by elemental analysis.
Intercalation of Tartrazine Into ZnAl and MgAl Layered Double Hydroxides
Authors: Beneš Ludvík , Melánová Klára , Zima Vítězslav , Svoboda Jan
Published: March 2005

The intercalates of Tartrazine Acid Yellow were prepared by heating [Zn0.67Al0.33(OH)2]- (CO3)0.165·0.5H2O or [Mg0.70Al0.30(OH)2](CO3)0.15·0.5H2O with a solution of an acid form of Tartrazine in an open reaction vessel or by stirring the powdered calcined hydrotalcites with a Tartrazine solution at room temperature. The intercalates were characterized by chemical and thermal analysis, X-ray powder diffraction and UV-VIS spectroscopy. The intercalates prepared by stirring the calcined host powders have worse crystallinity than those prepared by ion exchange. A possible arrangement of the Tartrazine anions in the intercalates was suggested on the basis of their chemical compositions and interlayer distances, taking into account van der Waals dimensions of the guest anions and assuming that the structure of the host layers is not changed during the intercalation process.
Modelling habitat requirement of European fishes: do species have similar responses to local and regional environmental constraints?
Authors: Pont D , Hugueny B , Oberdorff T
Published: March 2005

To test the hypothesis that different species have similar responses to local and regional environmental constraints, we modelled the occurrences of 13 species using a data set of 413 undisturbed river reaches. Three environmental descriptors were considered at the local scale (river slope, river width, and upstream drainage area) and three at the regional scale (mean annual and mean range air temperature and basin unit). Using multiple logistic regression modelling techniques, we correctly predicted the occurrence of 11 of the 13 retained species. The hierarchical partitioning analysis that we used allowed us to jointly consider all possible models in a multiple regression setting and to evaluate the independent explanatory power of each of our five environmental variables. We reject the hypothesis of a common species response to the environmental constraints. Species inhabiting upstream river reaches (bullhead (Cottus gobio), brown trout (Salmo trutta), minnow (Phoxinus phoxinus), and stone loach (Barbatula barbatula)) are more sensitive to basin unit. All species representative of downstream areas (barbel (Barbus barbus), dace (Leuciscus leuciscus), chub (Leuciscus cephalus), gudgeon (Gobio gobio), roach (Rutilus rutilus), bleak (Alburnus alburnus), and perch (Perca fluviatilis)) exhibit a positive continuous response to the drainage area, in agreement with the view of a continuous increase of local richness downstream. River slope is an important variable for all species. Main species habitat requirements are discussed for each species.
Comparing naturally occurring stable isotopes of nitrogen, carbon, and strontium as markers for the rearing locations of Atlantic salmon (Salmo salar)
Authors: Kennedy Brian P , Chamberlain C Page , Blum Joel D , Nislow Keith H , Folt Carol L
Published: March 2005

We compared the success of using naturally occurring stable isotopes of N, C, and Sr as markers for the rearing locations of juvenile salmon. We analyzed the isotopic signatures (δ15N and δ13C in muscle and scales and 87Sr/86Sr in otoliths) of >200 juvenile Atlantic salmon (Salmo salar) from 12 tributaries of the Connecticut River, USA. Young salmon had distinct N and C signatures 5 weeks after stocking. Signatures were stable over the summer although δ13C varied more than δ15N or 87Sr/86Sr. Scale and muscle signatures were highly correlated, demonstrating the feasibility of nonlethal sampling using fish scales. Some C (but not N) signature from the hatchery was retained in scales of 3-month-old fish, implicating scale annuli as a repository for past C signatures. The δ15N values successfully differentiated fish from tributaries with differences in land use (e.g., agricultural versus forested; ≈ 33% of sites); the δ13C values differentiated fish from 45% of sites. Based upon a discriminant-function analysis, group membership of individuals was correctly predicted in 44.3% (74 of 167) of cases for which both N and C were analyzed. In combination, N and C isotopes differentiated 73% of study sites, which was close to the success of Sr isotopes in the same system (83%).
Role of osmotic suction in swelling of salt-amended clays
Authors: Rao Sudhakar M , Shivananda P
Published: March 2005

The present study examines the influence of extraneous salt addition on pore-fluid osmotic suction of a clay soil. The dependence of swell potentials of the salt-amended clay specimens on initial pore-fluid osmotic suction is also examined. The osmotic suctions predicted by Van't Hoff's equation are in excess or smaller than the values calculated from the pore water electrical conductivity, depending on whether the Van't Hoff factor in the Van't Hoff equation is included or not. Experimental results suggest that the salt-amended specimens absorbed water and swelled in response to matric suction and chemical concentration gradients on inundation with water in oedometer cells. Salt also diffused from the soil pores of salt-amended specimens to the reservoir water in oedometer cells in response to chemical concentration gradients. Reduction in effective stress from osmotic flow into the soil specimen and increase in interparticle repulsion from reduction in pore-water salt concentration rendered the total swell potentials of salt-amended specimens independent of initial pore-fluid osmotic suction. The initial pre-fluid osmotic suction does, however, significantly affect the rate of swelling.Key words: clays, chemical properties, swell potential, suction.
Tree seedling growth, survival, and morphology in response to landscape-level variation in soil resource availability in northern Michigan
Authors: Schreeg Laura A , Kobe Richard K , Walters Michael B
Published: March 2005

To investigate causes of tree species distributions across soil resources in northern Michigan, we conducted a seedling transplant experiment with five species showing different site affinities: Acer saccharum Marsh. (sugar maple), Prunus serotina Ehrh. (black cherry), and Fraxinus americana L. (white ash), which are associated with high-fertility mesic moraine; Quercus rubra L. (red oak), associated with intermediate sites; and Quercus velutina Lam. (black oak), associated with low-fertility droughty outwash sites. Seedlings were planted in plots stratified across variation in light and soil nutrient and water availability. After one growing season, under 14%27% canopy openness, species tended to trade off between high survival on outwash versus high relative growth rate of root + stem mass (RGRrs) on moraine. The high survivorship of black and red oak on outwash was associated with greater root and whole-plant mass in comparison with sugar maple, white ash, and black cherry. High RGRrs on high-fertility moraine for these latter species was associated with high fine root area per unit whole-plant mass and plasticity to increase specific root area in response to increased soil resources. We did not detect a similar survivalgrowth trade-off for seedlings grown at lower light (3%10%) on intermediate versus high-fertility sites. Overall, these results suggest that species distributions across soil resource gradients can in part be explained by a trade-off between tolerance of low soil resources versus competitive ability (i.e., growth) under high soil resources.
Effects of fire severity on early development of understory vegetation
Authors: Wang G. Geoff , Kemball Kevin J
Published: March 2005

Four boreal mixedwood stands burned by the 1999 Black River wildfire in southeastern Manitoba were sampled to examine the effects of fire severity on early regeneration dynamics of understory vegetation. In each stand, three fire severity classes (scorched, lightly burned, and severely burned) were identified based on the degree of forest floor consumption, and six plots per severity class were randomly selected. Variation in fire severity significantly affected the initial regeneration of the understory plant community. Regeneration response after fire was largely controlled by interactions between fire severity and species' regeneration strategy. Establishment of invaders, seed bankers, and sprouters was best on severely burned, lightly burned, and scorched plots, respectively. Species richness and Shannon's diversity index was reduced by severe fire only in the first postfire year. However, the effects of fire severity on species abundance and composition persisted through the entire study period (19992002). Rapid changes in the understory plant community were only observed during the initial 3 postfire years, regardless of fire severity. At the end of the study, herbaceous plants were the most dominant component, with woody plants being a codominant component on scorched plots, and nonvascular plants being a codominant component on severely burned plots.
Soil respiration and soil carbon balance in a northern hardwood forest ecosystem
Authors: Fahey T J , Tierney G L , Fitzhugh R D , Wilson G F , Siccama T G
Published: March 2005

Soil C fluxes were measured in a northern hardwood forest ecosystem at the Hubbard Brook Experimental Forest to provide insights into the C balance of soils at this long-term study site. Soil CO2 emission (FCO2) was estimated using a univariate exponential model as a function of soil temperature based on 23 measurement dates over 5 years. Annual FCO2 for the undisturbed northern hardwood forest was estimated at 660 ± 54 g C·m2·year1. Low soil moisture significantly reduced FCO2 on three of the measurement dates. The proportion of FCO2 derived from the forest floor horizons was estimated empirically to be about 58%. We estimated that respiration of root tissues contributed about 40% of FCO2, with a higher proportion for mineral soil (46%) than for forest floor (35%). Soil C-balance calculations, based upon evidence that major soil C pools are near steady state at this site, indicated a large C flux associated with root exudation plus allocation to mycorrhizal fungi (80 g C·m2·year1, or 17% of total root C allocation); however, uncertainty in this estimate is high owing especially to high error bounds for root respiration flux. The estimated proportion of FCO2 associated with autotrophic activity (52%) was comparable with that reported elsewhere (56%).
Effects of repeated fertilization on needle longevity, foliar nutrition, effective leaf area index, and growth characteristics of lodgepole pine in interior British Columbia, Canada
Authors: Amponsah Isaac G , Comeau Philip G , Brockley Robert P , Lieffers Victor J
Published: March 2005

We investigated the effects of repeated fertilization (either periodically every 6 years or annual fertilization) on needle longevity and growth response in two juvenile lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) stands in the interior of British Columbia, Canada. Annual fertilization decreased needle longevity by 23% at the Kenneth Creek site and by 30% at Sheridan Creek, compared with the control treatments at each site. At Sheridan, repeated fertilization significantly increased effective leaf area index, foliated shoot length, and annual shoot growth. However, none of these variables was significantly altered by repeated fertilization at Kenneth. At both locations, fertilization elevated nutrient concentrations in the current year's foliage. Annual fertilization increased nitrogen concentration in mid-crown branches of retained cohorts (19982002) at both study sites. Furthermore, annual nitrogen addition apparently induced or exacerbated copper and iron deficiency in these stands, especially at Kenneth Creek, which may be related to the premature loss of foliage. Nutrient imbalance may also be related to poor effective leaf area index and growth response at Kenneth Creek. Stem growth efficiency declined with annual fertilization at Kenneth Creek because of accelerated turnover of needles, increased allocation of growth to branches, and probably reduced photosynthetic capacity.
COMMUNICATION BETWEEN SYNCHRONIZED RANDOM NUMBER GENERATORS
Authors: YAO WEIGUANG , YU PEI , ESSEX CHRISTOPHER
Published: March 2005

In most published chaos-based communication schemes, the system's parameters used as a key could be intelligently estimated by a cracker based on the fact that information about the key is contained in the chaotic carrier. In this paper, we will show that the least significant digits (LSDs) of a signal from a chaotic system can be so highly random that the system can be used as a random number generator. Secure communication could be built between the synchronized generators nonetheless. The Lorenz system is used as an illustration.
LOCAL AND GLOBAL HOPF BIFURCATION IN A DELAYED HEMATOPOIESIS MODEL
Authors: SONG YONGLI , WEI JUNJIE , HAN MAOAN
Published: March 2005

In this paper, we consider the following nonlinear differential equation [Formula: see text] We first consider the existence of local Hopf bifurcations, and then derive the explicit formulas which determine the stability, direction and other properties of bifurcating periodic solutions, using the normal form theory and center manifold reduction. Further, particular attention is focused on the existence of the global Hopf bifurcation. By using the global Hopf bifurcation theory due to Wu [1998], we show that the local Hopf bifurcation of (1) implies the global Hopf bifurcation after the second critical value of the delay τ. Finally, numerical simulation results are given to support the theoretical predictions.
CLASSIFICATION OF BURSTING MAPPINGS
Authors: IZHIKEVICH EUGENE M. , HOPPENSTEADT FRANK
Published: March 2005

When a system's activity alternates between a resting state (e.g. a stable equilibrium) and an active state (e.g. a stable periodic orbit), the system is said to exhibit bursting behavior. We use bifurcation theory to identify three distinct topological types of bursting in one-dimensional mappings and 20 topological types in two-dimensional mappings having one fast and one slow variable. We show that different bursters can interact, synchronize, and process information differently. Our study suggests that bursting mappings do not occur only in a few isolated examples, rather they are robust nonlinear phenomena.
MAGNITUDE OF ALCOHOL-RELATED MORTALITY AND MORBIDITY AMONG U.S. COLLEGE STUDENTS AGES 18–24: Changes from 1998 to 2001
Authors: Hingson Ralph , Heeren Timothy , Winter Michael , Wechsler Henry
Published: March 2005

▪ Abstract  Integrating data from the National Highway Traffic Safety Administration, the Centers for Disease Control and Prevention, national coroner studies, census and college enrollment data for 18–24-year-olds, the National Household Survey on Drug Abuse, and the Harvard College Alcohol Survey, we calculated the alcohol-related unintentional injury deaths and other health problems among college students ages 18–24 in 1998 and 2001. Among college students ages 18–24 from 1998 to 2001, alcohol-related unintentional injury deaths increased from nearly 1600 to more than 1700, an increase of 6% per college population. The proportion of 18–24-year-old college students who reported driving under the influence of alcohol increased from 26.5% to 31.4%, an increase from 2.3 million students to 2.8 million. During both years more than 500,000 students were unintentionally injured because of drinking and more than 600,000 were hit/assaulted by another drinking student. Greater enforcement of the legal drinking age of 21 and zero tolerance laws, increases in alcohol taxes, and wider implementation of screening and counseling programs and comprehensive community interventions can reduce college drinking and associated harm to students and others.
Serum Insulin-Like Growth Factor I Levels in Growth Hormone-Deficient Adults: Influence of Sex Steroids
Authors: Jørgensen Jens O.L. , Christensen Jens J. , Krag Morten , Fisker Sanne , Ovesen Per , Christiansen Jens S.
Published: March 2005

Measurement of serum insulin-like growth factor I (IGF-I) concentrations remains the single most important tool in the evaluation of growth hormone (GH) replacement in GH-deficient adults, and the therapeutic goal is to maintain the level within the age-adjusted normal range. In healthy adults, IGF-I levels do not differ between males and females, whereas spontaneous GH secretion is approximately twofold higher in females. Untreated GH-deficient women exhibit lower IGF-I levels compared with men, and the increase in serum IGF-I during GH replacement is also significantly less. Put together, these data suggest resistance to GH in women, which in healthy individuals is compensated for by increased GH secretion. Administration of oral oestrogen in healthy post-menopausal women suppresses hepatic IGF-I production and increases pituitary GH release, and oral oestrogen replacement in women with GH deficiency lowers IGF-I concentrations and increases the amount of GH necessary to obtain IGF-I target levels during treatment. These data clearly suggest that hepatic suppression of IGF-I production by oestrogen subserves the gender difference in GH sensitivity, but it is also likely that sex steroids may interact with the GH/IGF axis at further levels. There is also circumstantial evidence to indicate that testosterone stimulates IGF-I production, and it is speculated that a certain threshold level of androgens is essential to ensure hepatic IGF-I production. Whether these data should translate into earlier discontinuation of oestrogen replacement therapy in adult women with hypopituitarism merits consideration.
Postoperative Interleukin-6 and Cortisol Concentrations in Elderly Patients with Postoperative Confusion
Authors: Kudoh Akira , Takase Hajime , Katagai Hiroshi , Takazawa Tomoko
Published: March 2005

Objective: To investigate changes in plasma interleukin (IL)-6, cortisol or noradrenaline concentrations after surgery in elderly patients with postoperative confusion. Methods: We studied 80 patients aged 70–90 years undergoing abdominal surgery and measured plasma IL-6, cortisol or noradrenaline concentrations before surgery, at the end of surgery, and 24 and 48 h after surgery. Results: Plasma IL-6 concentrations in elderly patients with postoperative confusion were 83.2 ± 30.5, 49.3 ± 14.1 and 42.9 ± 19.4 pg·ml–1 at the end of surgery, and 24 and 48 h after surgery, respectively, being significantly higher than in elderly patients without postoperative confusion (58.0 ± 37.5, 36.1 ± 20.0 and 28.2 ± 16.7 pg· ml–1). Plasma cortisol concentrations in elderly patients with postoperative confusion (42.2 ± 7.8, 38.3 ± 8.3 and 33.1 ± 8.4 µg·dl–1 at the end of surgery, and 24 and 48 h after surgery, respectively) were significantly higher than in elderly patients without postoperative confusion (32.9 ± 6.7, 30.4 ± 8.6 and 25.6 ± 6.5 µg·dl–1, respectively). There were no significant differences in plasma norepinephrine concentrations at all sampling points between elderly patients with and without postoperative confusion. However, plasma IL-6 and cortisol concentrations were related in elderly patients with postoperative confusion (at the end of surgery and 24 and 48 h after surgery). However, there was no relationship between plasma IL-6 and cortisol concentrations 24 and 48 h after surgery in elderly patients without postoperative confusion. Conclusion: Elderly patients with postoperative confusion had increased plasma IL-6 and cortisol concentrations. The interaction between IL-6 and cortisol after surgery is associated with developing postoperative confusion in the elderly patients.
Mechanisms of Pancreatic Fibrosis
Authors: Apte M.V. , Wilson J.S.
Published: March 2005

Pancreatic fibrosis, a characteristic histopathological feature of chronic pancreatitis, is no longer considered an epiphenomenon of chronic injury, but an active process that may be reversible in the early stages. The identification and characterization of pancreatic stellate cells (PSCs) in recent years has had a significant impact on research into pancreatic fibrogenesis. Accumulating evidence from both in vivo studies (using human pancreatic sections and experimental models of pancreatic fibrosis) and in vitro studies (using cultured pancreatic stellate cells) indicates a key role for activated PSCs in the fibrotic process. These cells are now known to be activated by ethanol and its metabolites and by several factors that are upregulated during pancreatic injury including growth factors, cytokines and oxidant stress. Based on this knowledge, potential antifibrotic strategies such as antioxidants and cytokine inhibition have been assessed in experimental models. Studies are also underway to characterise the signaling pathways/molecules responsible for mediating PSC activation, in order to identify potential therapeutic targets for the inhibition of PSC activation, thereby preventing or reversing the development of pancreatic fibrosis.
Measurement of Residual Adenoma after Transurethral Resection of the Prostate by Transurethral Enucleation Technique
Authors: Shimizu Yuji , Hiraoka Yasunori , Iwamoto Kazuya , Takahashi Hirohumi , Abe Hiroyuki
Published: March 2005

Objective: Transurethral resection of the prostate (TURP) leaves a lot of residual adenoma and has a high recurrence rate, but the residual adenoma weight has not been measured surgically. Using surgery we tried to measure the residual adenoma after TURP. Material and Methods: Total adenoma resection was performed via standard TURP in 64 cases with benign prostatic hyperplasia and the weight of the residual adenoma was measured by transurethral enucleation (TUE) of the prostate. Results: Prostate volume averaged 37.4 ml and adenoma volume averaged 20.6 ml by TRUS. The average weight of the prostate removed by TURP was 9.8 g. After TURP residual adenoma was confirmed in all cases by TUE, and the average weight of the residual adenoma was 10.2 g. The total average prostate volume removed by TURP and TUE was 20.1 g. The average residual rate of the adenoma removed by TURP was 54.5%. Conclusion: TURP leaves about half of the adenoma. Therefore, TURP might be very difficult for complete resection of an adenoma.
Lower Urinary Tract Reconstruction in Ectopic Ureteroceles
Authors: Ziylan Orhan , Oktar Tayfun , Korgali Esat , Nane Ismet , Alp Turgut , Ander Haluk
Published: March 2005

Objectives: The management of ectopic ureteroceles is a challenging entity in pediatric urology. In our study, we aimed to determine the outcome after lower urinary tract reconstruction in ectopic ureteroceles. Materials and Methods: A total of 18 (12 girls, 6 boys) children with ectopic ureteroceles, treated between 1993 and 2003 by complete reconstruction, were enrolled in the study and their records were retrospectively reviewed. Results: Ureterocele was found to be unilateral in 16 and bilateral in 2 children. Four patients had been previously managed by endoscopic interventions and 1 patient underwent partial nephrectomy. Ureterocelectomy was performed on 20 renal units, and of these 20 renal units, 9 underwent heminephroureterectomy, 1 ureterectomy, and 3 (with single system ureteroceles) nephroureterectomy. Seven (35%) renal units with adequate function underwent ureteral reimplantations. After a mean follow-up of 5.4 years (range 4 months to 9.5 years), no patient required a second procedure. Contralateral reflux that developed in 2 children after surgical treatment resolved spontaneously after 1 year of follow-up. Conclusion: In the management of ectopic ureterocele, lower urinary tract reconstruction is an effective treatment alternative. According to the functional status of the renal parenchyma involved, the surgical procedure was limited to the lower urinary tract in 35% of the cases.
Effects of Early Phase of Preconditioning on Rat Testicular Ischemia
Authors: Ceylan Haluk , Yüncü Mehmet , Armutçu Ferah , Gürel Ahmet , Bağcı Cahit , Demiryürek A. Tuncay
Published: March 2005

Introduction: Brief episodes of ischemia followed by periods of reperfusion generate a powerful protective mechanism in cell, tissue or organ, which increase the resistance to further ischemic damage. This is known as ischemic preconditioning, and has not been investigated in testis. The present experiments were undertaken to determine whether early phase of ischemic preconditioning is evident in rat testis. Materials and Methods: Surgery was conducted under thiopental (60 mg/kg, intraperitoneal) anesthesia in male Wistar rats. Surgical procedures were performed through a midline incision. Group 1 was designed as a sham group. In group 2, which served as the ischemia group, the animals were subjected to unilateral testicular torsion by rotating the left testis 720° in a clockwise direction. Then, this testis was maintained in the torsion position by fixing with a silk suture to the scrotal wall for 90 min. In groups 3 and 4, 5 or 10 min ischemia followed by 10 min reperfusion was introduced, respectively, to induce single cycle ischemic preconditioning. In group 5, which served as the multiple cycle preconditioning group, 3 cycles of 10 min ischemia and 10 min reperfusion were applied prior to 90 min ischemia. Both ipsilateral and contralateral testes were removed from the rats at the end of the experimental periods, and tissue malondialdehyde (MDA), nitric oxide (NO) levels, xanthine oxidase (XO), myeloperoxidase (MPO) and superoxide dismutase (SOD) activities were measured. Both testes were also evaluated histologically, assessing interstitial edema, congestion, hemorrhages, rupture of tubules and Leydig cell proliferation. Results: 90 min ischemia produced a marked increase in MDA level in left testis. However, all ischemic preconditioning protocols used in this study did not show any significant modification in MDA, NO levels or XO, MPO and SOD activities. Histological grading scale was also similar in ischemia and preconditioning groups. Conclusion: These results suggest that there are no protective effects with ischemic preconditioning in rat testis as showed by biochemical analysis and histological examinations.
Catechol-O-Methyltransferase and Monoamine Oxidase B Genes and Susceptibility to Sporadic Parkinson’s Disease in a Polish Population
Authors: Białecka Monika , Droździk Marek , Honczarenko Krystyna , Gawrońska-Szklarz Barbara , Stankiewicz Jan , Dąbrowska Ewa , Kubisiak Maciej , Kłodowska-Duda Gabriela , Opala Grzegorz
Published: March 2005

Recent reports have proved that genetic factors play a role in the pathogenesis of sporadic Parkinson’s disease (PD). It has been suggested that polymorphisms in monoamine oxidase B (MAOB) and catechol-O-methyltransferase (COMT) might increase the risk of PD. A total of 210 Polish patients with sporadic PD and 152 healthy controls were studied. The MAOB and COMT polymorphisms were identified using the polymerase chain reaction-restriction fragment length polymorphism method. The MAOB allele and genotype frequencies in PD patients did not differ significantly from the controls. A statistically lower frequency of the COMTLL genotype in patients with parkinsonism was found. The combined haplotype of the MAOB G (G/G) and COMTHL genotype showed a fourfold increase (p < 0.05) in the risk of PD in female patients in this Polish population.
Anseriform Brain and Its Parts versus Taxonomic and Ecological Categories
Authors: Kalisińska Elżbieta
Published: March 2005

The size of the brain and its macro-anatomical parts in 206 birds representing 19 anseriform species and 4 tribes (Anserini, Anatini, Aythyini and Mergini) was the subject of a comparative analysis. The comparisons involved two aspects: taxonomic (differences among species within tribes and differences among tribes) and ecological (diet composition: vegetation, invertebrates, or fish and the foraging mode: browsing, dabbling, shallow diving, and deep diving). The relative size of the encephalon (E) and its parts (optic tectum, OT; cerebellum, C; brain stem, BS; hemispheres, H) were described using appropriate indices. Five of them, called the cerebral-body indices (E/BW, OT/BW, C/BW, BS/BW, H/BW), involved a ratio between the weight of E or its parts and that of the body (BW). Four intracerebral indices (OT/E, C/E, BS/E, H/E) and allometric equations were used as well. Almost all the indices showed a high intraspecific variability within the Anserini and Mergini; on the other hand, the intracerebral indices did not differ between the species of the Anatini and Aythyini (except for OT/E in the Aythyini). Between-tribe differences were reflected in all 9 indices. The birds feeding on different diets were found to differ in their OT/E and H/E. The herbivorous anserifom OT/E was clearly lower than that of those birds feeding on invertebrates and fish. The highest OT/E was that of the piscivorous birds. In terms of foraging mode, significant differences were revealed in 7 out of the 9 indices used (differences in OT/BW and C/BW proved non-significant). OT/E of the browsing birds was clearly lower than that of the deep diving ducks; BS/E of the browsers was much lower than that of the dabbling and shallow diving ducks. Geese and swans (browsers) showed much higher H/E compared to the deep diving sea ducks. The latter revealed the highest C/E, but significant differences were detected only in comparison with C/E of the shallow diving ducks. The taxonomic (among tribes) and ecological comparisons showed more differences in the intracerebral indices than in the cerebral-body indices.
Sacral Nerve Stimulation for Faecal Incontinence
Authors: Pillinger Stephen H. , Gardiner Angela , Duthie Graeme S.
Published: March 2005

Faecal incontinence is a common problem. Conservative measures are effective in a significant proportion of patients. Failure of conservative management has until recently meant recourse to surgical intervention. Surgical treatment is often associated with disappointing results. Recently, sacral nerve stimulation (SNS) has been developed as a minimally invasive, effective technique for idiopathic and acquired faecal incontinence. The technique uses chronic low-level electrical stimulation of the sacral nerves, or neuromodulation, to produce a clinically beneficial effect on the distal colon and rectum, the pelvic floor and the anal sphincter complex. SNS is a 2-stage procedure: a diagnostic stage – temporary percutaneous nerve evaluation (PNE), and a therapeutic stage – permanent SNS. The predictive value of PNE is high, and the surgical trauma and morbidity of both procedures extremely low. The technique has been adapted from its original application in urinary dysfunction. It is almost impossible to produce level 1 evidence for this type of intervention; however, the results are superior to other interventions. Patient selection criteria are evolving, but there is a growing body of evidence that supports its use as first-line treatment for faecal incontinence in patients where conservative measures have failed.
Local Excision of Rectal Cancer: Review of Literature
Authors: Nastro Piero , Beral Daniel , Hartley John , Monson John R.T.
Published: March 2005

In selected patients, local excision of rectal cancer may be an alternative to radical surgery such as abdominoperineal excision of the rectum or anterior resection. Local excision carries lower mortality and morbidity, without the functional disturbance or alteration in body image that can be associated with radical surgery. There are several techniques of local therapy for rectal cancer, with most experience being available in transanal excision. Transanal endoscopic microsurgery is also used but experience with this newer technique is limited. Patient selection is the most important factor in successful local excision, however specific criteria for selecting patients have not been universally accepted. Review of the published literature is difficult because of the variation in adjuvant therapy regimes and follow-up strategies, as well as results reported in terms of local recurrence and survival rates. There is increasing evidence to suggest that local excision should be restricted to patients with T1 stage rectal cancer without high-risk factors. The place for local excision in patients with T2 or high-risk T1 tumours requires prospective, randomised multi-centre trials comparing radical surgery with local excision, with or without adjuvant therapy.
A Multicenter, Open-Label Study to Evaluate Satisfaction and Menopausal Quality of Life in Women Using Transdermal Estradiol/Norethindrone Acetate Therapy for the Management of Menopausal Signs and Symptoms
Authors: Adler George , Young Douglas , Galant Ron , Quinn Laura , Witchger Mary Sue , Maki Kevin C.
Published: March 2005

Aim: This multicenter, open-label, single-arm study evaluated subject satisfaction and improvements in menopausal quality of life among menopausal women using the CombiPatch® transdermal system consisting of 17β-estradiol 0.05 mg plus norethindrone acetate 0.14 mg in a matrix patch formulation. Methods: The 193 postmenopausal women between the ages of 45 and 65 years who comprised the modified intent-to-treat population (at least one patch and one efficacy assessment) were required to have reported at least five daily moderate-to-severe hot flashes and episodes of nocturnal sweating upon study entry for at least 1 month and applied one patch twice a week for 12 weeks. At weeks 0, 6, and 12, the women completed the Menopause-Specific Quality of Life (MENQOL) Questionnaire and, as a secondary study outcome, reported the scale of their application site discomfort. During weeks 1–12, they also kept diary records of number and severity of hot flashes and four other menopausal symptoms. Skin tolerance and adherence of the transdermal system were evaluated at weeks 6 and 12 by qualified evaluators. At week 6 and the end of the study, both subjects and physicians rated their satisfaction with the system. Results: Among women in the modified intent-to-treat population, transdermal 17β-estradiol plus norethindrone acetate significantly reduced the mean daily number of moderate-to-severe hot flashes experienced by women from 4.1 at week 1 to 0.6 at week 12 (p < 0.0001). The mean ratings of headache severity, insomnia, and vaginal irritation/dryness also improved significantly by week 6 and were maintained at week 12. At week 12, 92.4% of the subjects and 97.3% of the physicians reported that they were ‘satisfied’ or ‘very satisfied’ with the transdermal hormone delivery system. Conclusions: The results of this study compare favorably with previous placebo-controlled studies of transdermal hormone therapy in managing menopausal signs and symptoms. Furthermore, quality of life was significantly improved by the transdermal hormone therapy system, and both subjects and physicians reported high levels of satisfaction.
Spatial Heterogeneity of Endothelial Phenotypes Correlates With Side-Specific Vulnerability to Calcification in Normal Porcine Aortic Valves
Authors: Simmons Craig A. , Grant Gregory R. , Manduchi Elisabetta , Davies Peter F.
Published: March 2005

Calcific aortic valve sclerosis involves inflammatory processes and occurs preferentially on the aortic side of endothelialized valve leaflets. Although the endothelium is recognized to play critical roles in focal vascular sclerosis, the contributions of valvular endothelial phenotypes to aortic valve sclerosis and side-specific susceptibility to calcification are poorly understood. Using RNA amplification and cDNA microarrays, we identified 584 genes as differentially expressed in situ by the endothelium on the aortic side versus ventricular side of normal adult pig aortic valves. These differential transcriptional profiles, representative of the steady state in vivo, identify globally distinct endothelial phenotypes on opposite sides of the aortic valve. Several over-represented biological classifications with putative relevance to endothelial regulation of valvular homeostasis and aortic-side vulnerability to calcification were identified among the differentially expressed genes. Of note, multiple inhibitors of cardiovascular calcification were significantly less expressed by endothelium on the disease-prone aortic side of the valve, suggesting side-specific permissiveness to calcification. However, coexisting putative protective mechanisms were also expressed. Specifically, enhanced antioxidative gene expression and the lack of differential expression of proinflammatory molecules on the aortic side may protect against inflammation and lesion initiation in the normal valve. These data implicate the endothelium in regulating valvular calcification and suggest that spatial heterogeneity of valvular endothelial phenotypes may contribute to the focal susceptibility for lesion development.