bluuebunny/crossref_metadata_2025 huggingface dataset:
Electron Spin–Lattice Relaxation Times of Spin Probes in Aqueous Dispersions of a Unique Amphiphilic Compound Obtained by a Saturation Recovery Method
Authors: Nakagawa Kouichi
Published: July 2008

Electron spin–lattice relaxation times (T1e) of a unique nonionic amphiphilic compound, (poly(oxyethylene) hydrogenated castor oil, HCO) in aqueous dispersions, were investigated by electron paramagnetic resonance (EPR) and saturation recovery (SR) spectroscopies. The spin probes, 5-doxylstearic acid (5-DSA) and 3β-doxyl-5α-cholestane (CHL), were used to obtain T1e values for the head group region in the HCO membrane. Analysis of SR signals from both probes showed that the T1e value (≈5 μs at 20 °C) indicates relatively faster relaxation behavior in the region than that of 12-DSA. No abrupt change (such as phase transition) of the relaxation time was observed in the temperature region studied. Thus, the present T1e results indicate relative flexibility for both probe moieties in the membrane throughout the temperatures studied.
Curium(III) Complexation with Desferrioxamine B (DFO) Investigated Using Fluorescence Spectroscopy
Authors: Moll Henry , Glorius Maja , Bernhard Gert
Published: July 2008

Hydroxamate-type siderophores like desferrioxamine B (DFO) are the most common siderophores ubiquitously found in the environment. These naturally occurring chelating substances have the potential to enhance the solubility and mobility of actinides by forming soluble complexes. The unknown interaction between curium(III) and aqueous DFO species is the subject of this paper. The reactions between soluble species of curium(III) and DFO were studied at trace curium(III) concentrations (3×10−7 M) in 0.1 M NaClO4 using time-resolved laser-induced fluorescence spectroscopy (TRLFS). Three Cm3+–DFO species, MpHqLr, could be identified from the luminescence spectra, CmH2DFO2+, CmHDFO+, and CmDFO, having emission maxima at 599, 611, and 614 nm, respectively. The large formation constants, logβ121=31.62±0.23, logβ111=25.70±0.17, and logβ101=16.80±0.40, compared to those of other chelating agents illustrate the unique complexation properties of hydroxamate-type siderophores. An indirect excitation mechanism for the curium(III) luminescence was observed in the presence of the DFO molecules.
Synthesis and Absolute Structure of (−)-Umtatin
Authors: Yamaguchi Seiji , Kobayashi Masahide , Harada Shin-ichiro , Miyazawa Masahiro , Hirai Yoshiro
Published: July 2008

A new preparation of 2-(hydroxymethyl)chromones was developed via the new regio-selective six-membered cyclization of 1-[o-(tert-butyldimethylsiloxy)phenyl]but-2-yn-1-ones by a three-step treatment with 1) diethylamine (activation of the γ-position), 2) KF-18-crown-6 (deprotection), and 3) silica-gel (cyclization). A naturally occurring chiral hydroxymethylfurochromone, (−)-umtatin, was synthesized starting from chiral (R)-(−)-2-isopropenyl-4,6-dimethoxy-2,3-dihydrobenzofuran, and the absolute structure was determined to R.
Structural Properties and Degree of Intramolecular Charge Transfer of an N-Alkyl Indoline–Tricyanoquinodimethane System
Authors: Murata Tsuyoshi , Nishimura Kazukuni , Enomoto Yuichiro , Honda Genki , Shimizu Yasuhito , Otsuka Akihiro , Saito Gunzi
Published: July 2008

A series of intramolecular charge-transfer compounds comprised of 1-alkyl-3,3-dimethyl-2-methyleneindoline (In, donor, n = alkyl chain length; 1–8, 10, 14, 16, 18, 20, and 22) and 7,8,8-tricyanoquinodimethane (=2-(4′-cyanomethylene-2′,5′-cyclohexadienylidene)malononitrile (3CNQ), acceptor) moieties linked through a π-bond, In–3CNQ were prepared, and their structures are discussed. The melting points of the In–3CNQ solids decreased with increasing alkyl chain length until reaching a minimum point (95 °C) at n=18, and then began to gradually increase, indicating self-aggregation of the alkyl chains. The In–3CNQ derivatives with long alkyl chains (n≥6) produced supercooled liquids displaying conspicuous color changes after melting. Diverse molecular packing patterns were observed in the crystal structures. Most In–3CNQ derivatives formed face-to-face and/or side-by-side dimeric motifs to cancel net dipole moments. I20–3CNQ formed a two-dimensional bilayer structure by π-stacking and self-assembly of the alkyl chains. Two types of molecular conformation, which significantly affect the electronic structures, were observed to be dependent on the alkyl chain length. A parameter to evaluate the degree of intramolecular charge transfer, namely bond length ratio, was proposed; it exhibited good agreement with solvatochromic shifts and molecular orbital calculations.
Nickel-Catalyzed [4+2+2]-Type Annulation Reaction of Cyclobutanones with Diynes and Enynes
Authors: Ashida Shinji , Murakami Masahiro
Published: July 2008

In the presence of a nickel(0) catalyst, cyclobutanones reacted with diynes to produce bicyclic eight-membered ring ketones. Cyclobutanones acted as a C4 unit in the formal [4+2+2]-type annulation reaction, which proceeded through a ring-expansion of a spirocyclic seven-membered oxanickelacycle to a nine-membered nickelacycle via β-carbon elimination. A similar annulation reaction was also examined with enynes.
Permeability Study of Lipid-Coated Capsules with Confocal Laser Scanning Microscope (CLSM)
Authors: Zhang Tianzhu , Ge Liqin , Chi Huimei
Published: July 2008

Based on our past work on the successfully fabricating giant liposomes, it is necessary to systematically study the capsules’ permeability. In this paper, fluorescence recovery after photo-bleaching (FRAP) experiment was carried out by confocal laser scanning microscope (CLSM) in order to quantify the 6-carboxyfluorescein (6-CF) molecules passing through capsules’ wall. The results showed that the diffusion coefficient of the pure multilayered polyelectrolyte (PE) capsules was similar to the one of partly the lipid-coated PE capsules. The diffusion coefficient for completely coated PE capsules catalyzed selectively by phospholipase A2 is similar to that of partly coated PE capsules.
Interfering Effect for the Cesium Ion-Exchange Property of Sodium Difluorotetrasilicate and Sodium Taeniolite by Alkaline-Earth Metal Ions
Authors: Suzuki Noriko , Komuro Tomokazu , Kanzaki Yasushi
Published: July 2008

The cesium ion-exchange behavior of sodium difluorotetrasilicate (Na-TSM) and sodium taeniolite (Na-TAE) was investigated in the presence of alkaline-earth metal ions. When Na-TSM was exchanged beforehand with alkaline-earth metal ions, the amount of ion-exchanged Cs+ decreased slightly compared to untreated Na-TSM. In contrast, when Cs+-TSM was used very little ion exchange occurred with alkaline-earth metal ions. The interlayer spacing of Na-TSM contracted during the ion-exchange reaction with Cs+ because interlayer water molecules were displaced. For the alkaline-earth metal ion exchange, interlayer water molecules were retained. Thus, the Cs+ exchange occurred on Na-TSM that was exchanged beforehand with alkaline-earth metal ions. The Cs+ exchange was superior to that observed for alkaline-earth metal ions in the mixed solutions. In contrast, the ion-exchange reaction occurred under all conditions examined with Na-TAE. In particular, even Cs+ exchange was observed on Na-TAE that was exchanged beforehand with alkaline-earth metal ions. Furthermore, alkaline-earth metal ions exchange was observed on Cs+-TAE.
Corruption in the Police: The Reality of the ‘Dark Side’
Authors: Caless Bryn
Published: July 2008

This article, the product of original research by the author into cases of police corruption facilitated by the ACPO Counter-Corruption Advisory Group from 1999 to 2000, analyses the nature of corruption in the police, arguing that although its incidence is very small, the effect of corruption in the police, both in terms of morale and in terms of the effect on cases before the courts, is substantial. The author, well experienced in the application of counter-corruption methods, proposes that the simplest and most direct inhibitors are often the most effective. Profiles of likely perpetrators are discussed, as are the characteristic experiences of policing which might tempt an officer into corrupt activity. This work blends applied research and academic analysis with professional knowledge.
Officer Firearms Assaults at Domestic Violence Calls: A Descriptive Analysis
Authors: Johnson Richard R.
Published: July 2008

Domestic violence calls pose great dangers for the safety of police officers in the US as thousands of police officers are assaulted annually while handling domestic violence and domestic disturbance calls. Each year many officers are injured or killed in these assaults, the majority of fatal assaults involving firearms. The present study is a descriptive analysis of 143 incidents of a firearm assault against 225 victim police officers who were handling domestic calls at the time of their victimisation. The characteristics of these cases are described at the incident, assailant, and officer levels. Comparisons are made with the characteristics of fatal police officer assaults in the US in general, and policy recommendations are offered.
Workforce Modernisation and Future Resilience within the Police Service in England and Wales
Authors: Loveday Barry
Published: July 2008

This article is based on a presentation given to the National Workforce Modernisation Programme Conference at Leeds in 2008. It argues that the issue of future police resilience should not stand in the way of modernisation and that while it may be used as a defence of the status quo there is growing evidence that reform can be expected to enhance police service delivery. It argues that the nature of police establishment growth has meant that there has been no attempt to match police numbers to police functions and that incremental growth, which has characterised police officer expansion, now means that it is difficult to defend current police numbers. This problem is made worse by the challenge presented by police abstraction rates, which appear to have increased in line with police establishment. It is also suggested that the increasing operational role of police staff is rarely taken into account by HMIC when assessing police performance even though many former police functions are now the responsibility of civilian personnel. As a result the threat to police resilience, used as a defence of current police establishment, may significantly exaggerate the challenge that workforce modernisation represents.
Antifouling activity of natural products from Brazilian seaweeds
Authors: da Gama Bernardo A.P. , Carvalho Ana G.V. , Weidner Kerstin , Soares Angelica R. , Coutinho Ricardo , Fleury Beatriz G. , Teixeira Valeria L. , Pereira Renato C.
Published: July 2008

Antifouling chemical defense is likely an evolutionary response to the ecological disadvantages of epibiosis, particularly for photosynthetic organisms. Seaweed natural products with antifouling activity can provide effective, environmentally friendly alternatives to currently used antifouling paint booster biocides. The aim of this work was to assess the antifouling potential of natural products from Brazilian littoral seaweeds. Crude organic extracts from 51 populations comprising 42 species of macroalgae from eight locations along the Brazilian coast were tested against a relevant fouling organism in laboratory bioassays, the brown mussel Perna perna. In five cases, antifouling activities of purified compounds were also tested. A total of nine macroalgae were also cultured and tested for the presence of inducible defenses against fouling. Ecologically relevant field tests were performed in 11 cases to confirm laboratory results. Despite the unbalanced number of macroalgae tested among different localities, there seems to be no latitudinal trend of increased antifouling activity towards lower latitudes, where fouling pressure is presumed to be higher. However, there was a clear phylogenetic pattern in antifouling activity, with red macroalgae having the highest proportion (55%) of active species (moderate or strong fouling inhibition), followed by brown macroalgae (14%). Green seaweeds never exhibited strong antifouling activity (≥80% inhibition of byssal attachment relative to controls). Some degree of induced antifouling defense was observed in seven species (78%). These results appear to support known trends of secondary metabolite production among seaweeds and suggest that research efforts should be focused on tropical red macroalgae in the quest for new antifoulants. On the other hand, it seems clear that macroalgal groups, such as green algae, must have mechanisms of defenses against fouling that are not chemical.
Screening strategies for obtaining novel, biologically active, fungal secondary metabolites from marine habitats
Authors: Schulz Barbara , Draeger Siegfried , dela Cruz Thomas Edison , Rheinheimer Joachim , Siems Karsten , Loesgen Sandra , Bitzer Jens , Schloerke Oliver , Zeeck Axel , Kock Ines , Hussain Hidayat , Dai Jingqui , Krohn Karsten
Published: July 2008

To determine the best sources of novel, biologically active metabolites, both endophytic fungi (plant isolates) and fungi associated with algae were isolated from plants and algae from marine habitats of the North, Baltic and Mediterranean Seas, Atlantic Ocean, and Gulf of Mexico. Following preselection of the isolates according to taxon and metabolic profiles, almost all were active in at least one of the tests for antibacterial, antifungal, and/or herbicidal activities. Metabolites isolated from the culture extracts belonged to diverse structural groups; 42% were previously unknown structures. Compared to fungi associated with algae, endophytic fungi were a better source of novel metabolites and antifungal culture extracts; they produced a higher number of metabolites per fungus. Microsphaeropsis spp. and Coniothyrium spp. synthesized the highest numbers of novel metabolites per isolate, and Geniculosporium, Nodulisporium and Phomopsis the greatest numbers of metabolites per isolate. Based on the proportion of novel to known metabolites, endophytic fungi from marine environments equalled endophytes from terrestrial habitats. Metabolic profiles (HPLC-DAD) of the saprophytic, marine fungi belonging to Dendryphiella spp. from diverse temperate and subtropical locations revealed that geographical source of the isolates had little qualitative effect on secondary metabolite production in this genus.
Application of kernel-based stochastic gradient algorithms to option pricing
Authors: Barty Kengy , Girardeau Pierre , Strugarek Cyrille , Roy Jean-Sébastien
Published: July 2008

We present an algorithm for American option pricing based on stochastic approximation techniques. Besides working on a finite subset of the exercise dates (e.g. considering the associated Bermudean option), option pricing algorithms generally involve another step of discretization, either on the state space or on the underlying functional space. Our work, which is an application of a more general perturbed gradient algorithm introduced recently by the authors, consists in approximating the value functions of the classical dynamic programming equation at each time step by a linear combination of kernels. The so-called kernel-based stochastic gradient algorithm avoids any a priori discretization, besides the discretization of time. Thus, it converges toward the optimum of the non-discretized Bermudan option pricing problem.

We present a comprehensive methodology to implement efficiently this algorithm, including discussions on the numerical tools used, like the Fast Gauss Transform, or Brownian bridge.

We also compare our results to some existing methods, and provide empirical statistical results.
Income disparities among hungarian micro-regions: The mover-stayer model
Authors: Major K.
Published: July 2008

It is known that the simple Markov chain model overestimates the long run horizon mobility of the income distribution process. Dissolving the homogeneity assumption of the Markov model may lead to better forecasts. One generalisation of the Markov model, the Mover-Stayer model assumes heterogenous population: some units are moving according to a common Markov chain, but there are some (unknown) units that are not moving at all. They are called stayers.Based on the Frydman (1984) methodology if we compute both the Markov and Mover-Stayer models for Hungarian micro-regions income data, we find that the Mover-Stayer model fits better the regional relative income data than the simple Markov model. Using likelihood ratio test statistics we show that the difference is highly significant. The method is also applied for spatially conditioned data. The results show that the high persistence of relative income positions is a remarkable feature of the Hungarian economy in 1990–2003 both on a country-wide scale and local level. We also demonstrate that forecasts made on a less reliant model might lead to very ambiguous results.
How do social-economic differences in residential characteristics affect mortality? A literature review
Authors: Bakacs Márta , Vitrai József
Published: July 2008

A szerzők azokat a hazai és nemzetközi kutatásokat tekintik át, amelyek az elmúlt 15 évben készültek, és a halandóságot, valamint az egészséget meghatározó társadalmi-gazdasági tényezők földrajzi megoszlása közötti kapcsolatot elemzik. Az 1990 óta megjelent hazai elemzések számos, a halandóságot befolyásoló területi társadalmi-gazdasági tényezőt azonosítottak, mint a település nagysága, a népsűrűség, a foglalkoztatottság, a jövedelem, az iskolázottság vagy az etnikai összetétel. Ezek az egyszerűbb statisztikai módszereket alkalmazó leíró vizsgálatok általában időben és térben aggregált adatokra épültek. A jelentősebb külföldi kutatásokban a területi mutatók mellé egyéni szintű adatokat is bevontak az elemzésekbe, és gyakran többszintű modellezést használtak. Az összetett elemzések esetenként ellentmondó eredményeit látva a kutatók olyan átfogó egészségkoncepciót hiányoltak, amely külön tudja választani az egészséget befolyásoló tényezők egyéni és populációs szintű hatásait. A legújabb egészségmodellekhez illeszkedő többszintű, szomszédsági információt is hasznosító statisztikai eljárások alkalmazása elvezethet az egészségegyenlőtlenségek okainak és szerepének pontosabb feltárásához.
Wiskott–Aldrich syndrome
Authors: Gulácsy Vera , Maródi László
Published: July 2008

A Wiskott–Aldrich-szindróma ritka, X-kromoszómához kötött, recesszív öröklődésmenetű, primer immundefektus, amelyet microthrombocytopenia, ekcéma és visszatérő fertőzések jellemeznek. A közlemény részletesen taglalja a Wiskott–Aldrich-szindróma molekuláris patológiáját, diagnosztikáját és klinikumát.
mRNA expression analysis and classification of colonic biopsy samples using oligonucleotide and cDNA microarray techniques
Authors: Galamb Orsolya
Published: July 2008

A vastagbéldaganatok korai diagnosztikája, terápiája, követése napjainkban sem teljesen megoldott. Munkánk során a vastagbéldaganatok biomarker-vizsgálatát, génexpressziós elemzését és osztályozását végeztük. Munkacsoportunk vizsgálatai alapján megállapítható, hogy a biopsziás minták oligonukleotid microarray-vizsgálati módszere az Affymetrix minőségi kritériumoknak messzemenően megfelelő, standardizált és jól reprodukálható. Megállapítottuk továbbá, hogy a Taqman mikrofolyadék-kártyarendszer alkalmas a chipen mért génexpressziós változások nagy teljesítményű, gyors és költséghatékony valós idejű PCR-es megerősítésére. Kimutattuk azt is, hogy az oszteopontin és az oszteonektin fokozatosan emelkedő mRNS- és fehérjeexpressziója erősen korrelál a vastagbél adenoma-dysplasia-carcinoma szekvencia előrehaladásával. Tíz, a colorectalis adenoma-dysplasia-carcinoma átmenettel párhuzamosan fokozódó mRNS-expressziójú, valós idejű PCR-rel is megerősített szöveti markert azonosítottunk, amelyet még nem írtak le az irodalomban. Vizsgálataink során 27, 13, illetve 10 „top” gént azonosítottunk, amelyek mRNS-expressziós mintázata a vastagbél-adenomával, a colorectalis carcinomával, illetve a gyulladásos bélbetegségekkel asszociálódik.
Vascular endothelial dysfunction, oxidative stress – a new topic within the referal section of Orvosi Hetilap
Authors: Fischer Tamás
Published: July 2008

A szerző a folyóirat-referáló rovat „Érendothel-funkciózavar, oxidatív stressz” tárgykörrel való bővítésének fontosságát szakmailag – a téma nagyságára való tekintettel – néhány önkényesen kiemelt kérdéskör kibontásával támasztja alá: Az endothelium a belső környezet állandóságát, integritását vigyázza, azt különböző anyagok termelésével-elválasztásával, azoknak egyensúlyban tartásával biztosítja. Ha az erek belfelületét, intimáját érő mechanikai, fizikai, kémiai, mikrobiológiai, immunológiai, genetikai károsító téyezők – vagy azok valamelyikének kombinációja – ellen foganatosított válaszreakció folyamán megbomlik az egyensúly az endothelium termelte vasoconstrictorok és vasodilatatorok, a növekedési faktorok és azok gátlói, a proinflammátorok és antiinflammátorok, a protrombotikus és fibrinolitikus tényezők között, endothel-működészavarról beszélünk. Az idült érbetegség, az atherosclerosis indító eseménye az erek hatalmas belfelületén, az endothelsejtekben megy végbe, ezt nevezzük
endotheldiszfunkciónak
. Az érpatogén tényezők, a rizikófaktorok mindegyike
endothel-működészavar
, endotheldiszfunkció indukálásával vezet idült (cardio)vascularis megbetegedéshez. Az élettani oxidatív metabolizmus során végbemenő fiziológiás szabad gyökös folyamatok – a védekező-kompenzáló endogén antioxidatív faktorok kimerülésekor –
oxidatív stresszt
, a veszélyeztető tényezők okozta endothel-működészavart okoznak. Nyomatékosan kiemelendő a „kauzális”, intracellulárisan, mitokondriálisan ható antioxidánsok (sztatinok, angiotenzinkonvertálóenzim-gátlók, angiotenzinreceptor-blokkolók, acetilszalicilsav, a harmadik generációs béta-blokkolók) terápiás, preventív terápiás fontossága, a humán érrendszer élettani, kórélettani, terápiás konszubsztancialitásának, egylényegűségének és az endotheldiszfunkció szisztémás jellegének, az érrendszeri eseményláncolat preventív terápiás jelentőségének kulcsfontossága. Az oxidatív stressz, a konszekutív endotheldiszfunkció területén végbement hatalmas fejlődés a klinikai látásmódot alapjaiban átalakító momentum.
Non-alcoholic fatty liver disease and cardiovascular risk
Authors: Ábel Tatjána , Fehér János
Published: July 2008

A nem alkoholos zsírmáj az átlagpopulációban 15–25%-ban fordul elő. Az alapvető eltérés a nem alkoholos zsírmáj és a metabolikus szindróma (2-es típusú diabetes mellitus, dyslipidaemia, hypertonia és obesitas) vonatkozásában az inzulinrezisztencia kialakulása. Lefolyása nem minden esetben jóindulatú folyamat, jól ismert a klinikai gyakorlatban idült májbetegséggé és cirrhosissá történő átalakulása, valamint együtt járhat hepatocellularis carcinoma kialakulásával is. A nem alkoholos zsírmáj emelkedett cardiovascularis kockázattal jár, és egyre inkább úgy tűnik, hogy nem pusztán az atherosclerosis markere, hanem korai mediátora is. Kezelése jelenleg a metabolikus szindrómába tartozó betegségek terápiájára irányul, amely a májműködést is javíthatja.
Amyloidosis and the digestive tract
Authors: Műzes Györgyi , Miheller Pál , Tulassay Zsolt
Published: July 2008

Az amyloidosis azoknak a szokatlan kórformáknak az egyike, amelyeket a beteg vizsgálatakor gyakran nem ismernek fel. Az elmúlt három évtized kutatásai komoly előrelépést jelentettek a kórkép biokémiai természetének, osztályozásának, patogenezisének, megnyilvánulási formáinak, felismerésének és a lehetséges kezelés mikéntjének megértése és elmélyítése tekintetében. A változatos klinikai megjelenés alapján az emésztőrendszeri amyloidosis diagnózisa valódi kihívás. Fennállásával elsősorban olyan 30 év feletti betegek esetében lehet és kell számolni, akik nem tisztázott hátterű hasmenésben, fogyásban, motilitási vagy felszívódási zavarban szenvednek.
Genetic Identity of Brook Trout in Lake Superior South Shore Streams: Potential for Genetic Monitoring of Stocking and Rehabilitation Efforts
Authors: Sloss Brian L. , Jennings Martin J. , Franckowiak Ryan , Pratt Dennis M.
Published: July 2008

Rehabilitation of migratory (“coaster”) brook trout Salvelinus fontinalis along Lake Superior's south shore is a topic of high interest among resource stakeholders and management agencies. Proposed strategies for rehabilitation of this brook trout life history variant in Wisconsin include supplemental stocking, watershed management, habitat rehabilitation, harvest regulations, or a combination thereof. In an effort to evaluate the success of coaster brook trout rehabilitation efforts, we collected genetic data from four populations of interest (Whittlesey Creek, Bois Brule River, Bark River, and Graveyard Creek) and the hatchery sources used in the Whittlesey Creek supplementation experiment. We characterized the genetic diversity of 30 individuals from each of four populations using 13 microsatellite DNA loci. Levels of genetic variation were consistent with those in similar studies conducted throughout the basin. Significant genetic variation among the populations was observed, enabling adequate population delineation through assignment tests. Overall, 208 of the 211 sampled fish (98.6%) were correctly assigned to their population of origin. Simulated F1 hybrids between two hatchery strains and the Whittlesey Creek population were identifiable in the majority of attempts (90.5‐100% accuracy with 0‐2.5% error). The genetic markers and analytical techniques described provide the ability to monitor the concurrent coaster brook trout rehabilitation efforts along Wisconsin's Lake Superior south shore, including the detection of hybridization between hatchery and native populations.
Ecology, Evolution, and Conservation of Lake‐Migratory Brook Trout: A Perspective from Pristine Populations
Authors: Fraser Dylan J. , Bernatchez Louis
Published: July 2008

Reintroduction or rehabilitation plans for fish populations in many systems (e.g., lakes) are complicated by limited data on ecological and genetic characteristics before human disturbances occurred. While no two lakes have identical physical and biological characteristics, a growing body of empirical evidence nevertheless indicates that parallel patterns of population structuring may evolve within northern temperate fish species. Examining the population structuring in undisturbed lakes of similar physical and biological characteristics may thus provide insight into the probable historical extent and causes of both population structuring and connectivity in human‐impacted lakes. Here, we review research on the population structuring and evolution of migratory brook trout Salvelinus fontinalis in a relatively undisturbed, postglacial lake (Mistassini Lake, Quebec). We provide information on lake habitat use, the morphology and life history characteristics of populations, diets, lakewide genetic population structure, seasonal migration characteristics between spawning and feeding areas, population evolutionary histories, and the prevalence of lake spawning. The biology of Mistassini Lake brook trout has a compelling number of similarities with what is known about that of the “coaster” form in Lake Superior and lake‐migratory brook trout elsewhere. Our review also has several implications for the rehabilitation of coaster populations with respect to (1) clarifying the degree of natural connectivity between populations; (2) predicting the likelihood of recolonization of vacant habitats; (3) choosing candidate source populations for translocations; and more broadly, (4) understanding the spatial scale of probable local adaptation. Mistassini Lake therefore provides a useful case study that applies to lake‐migratory trout elsewhere. We hope that our research will stimulate managers and biologists working on similar systems with pronounced human disturbances to consider the interplay between ecology and evolution in future conservation efforts.
Habitat Use and Movement Patterns of Brook Trout in Nipigon Bay, Lake Superior
Authors: Mucha Jamie M. , Mackereth Robert W.
Published: July 2008

Brook trout Salvelinus fontinalis are one of two salmonine species native to Lake Superior. Abundant and widely distributed a century ago, Lake Superior's brook trout (coasters) have been reduced to a few remnant stocks, probably as a result of exploitation and habitat loss. Twenty brook trout captured in Nipigon Bay, Lake Superior, were surgically implanted with radio transmitters and were located from June 1999 to October 2000. Brook trout locations were used to determine the characteristics of utilized lake habitat and to identify streams used for spawning and the spawning areas within them. These locations were also used to establish daily and seasonal movement patterns. A total of 638 locations were obtained during the tracking period, 483 occurring within Nipigon Bay and the remaining 155 within tributaries. Brook trout were located almost exclusively within the shallow nearshore areas of Nipigon Bay; 92% of the locations were less than 7 m deep and 94% were less than 400 m from shore. Brook trout occupied deeper areas with steeper shoreline slopes during July and August, when the water temperatures of shallow nearshore areas were at their highest. Following selected individuals for 24‐h periods revealed that brook trout often used deeper areas during daylight hours and moved to extremely shallow nearshore areas during the night. Radio‐tagged brook trout began ascending tributaries during late summer in both years of this study. The mean residency time for brook trout in tributaries was 46 d. Spawning occurred in early October, and most radio‐tagged brook trout returned to Lake Superior by mid‐October. Four different streams were used during the spawning period. Brook trout entering streams exhibited strong spawning site fidelity between years.
Migrations and Biological Characteristics of Adfluvial Coaster Brook Trout in a South Shore Lake Superior Tributary
Authors: Huckins Casey J. , Baker Edward A.
Published: July 2008

We used fish traps and electrofishing surveys to characterize the biology, life history traits, and potential biotic interactors important to the rehabilitation of native, adfluvial coaster brook trout Salvelinus fontinalis in Lake Superior. This study focused on the Salmon Trout River, Michigan, which is the site of the last known remnant population of adfluvial brook trout on the south shore of Lake Superior. The brook trout captured in passive traps (weirs) in the river ranged from 56 to 554 mm in total length (TL) and from 0 (young of the year) to 6 years of age. This population displayed a protracted 5‐month migration into the river but one that included relatively few fish. Coaster brook trout in this population appear to initiate adfluvial migrations near age 3 and 300 mm TL. Relative weight values increased with fish length and therefore reproductive life stage, possibly indicating the shift from river to lake habitats. This population of coaster brook trout is small and subject to potential biotic interactions with exotic species and population limitation because of an active fishery in the lake and river. Migratory runs of brook trout coincided with large runs of coho salmon Oncorhynchus kisutch, and the instream juvenile salmonid composition included proportionately high densities of coho salmon and rainbow trout O. mykiss. In addition, Floy tag return data indicated that exploitation of reproductive‐age Salmon Trout River coaster brook trout was at least 12% and may have been as high as 50% in the open waters of Lake Superior. A recent increase in the legal minimum length limit and reduction of the daily bag limit for recreational harvest may slow or reverse this trend.
Nearshore Habitat and Fish Community Associations of Coaster Brook Trout in Isle Royale, Lake Superior
Authors: Gorman Owen T. , Moore Seth A. , Carlson Andrew J. , Quinlan Henry R.
Published: July 2008

We characterized the nearshore habitat and fish community composition of approximately 300 km of shoreline within and adjacent to the major embayments of Isle Royale, Lake Superior. Sampling yielded 17 species, of which 12 were widespread and represented a common element of the Lake Superior fish community, including cisco Coregonus artedi, lake whitefish C. clupeaformis, round whitefish Prosopium cylindraceum, lake trout Salvelinus namaycush, rainbow smelt Osmerus mordax, lake chub Couesius plumbeus, longnose sucker Catostomus catostomus, white sucker C. commersonii, trout‐perch Percopsis omiscomaycus, ninespine stickleback Pungitius pungitius, burbot Lota lota, and slimy sculpin Cottus cognatus. The presence of brook trout S. fontinalis in an embayment was associated with the common species of the Isle Royale nearshore fish community, particularly cisco, longnose sucker, and round whitefish. However, brook trout were present in only five embayments and were common only in Tobin Harbor. Most Isle Royale embayments had broadly overlapping ranges of nearshore habitats. Within embayments, fish were distributed along a habitat gradient from less‐protected rocky habitat near the mouth to highly protected habitat with mixed and finer substrates at the head. Embayments with brook trout had greater mean protection from the open lake, greater variation in depth, greater mean cover, and higher mean frequencies of large substrates (cobble, boulder, and bedrock). Within those embayments, brook trout were associated with habitat patches with higher mean frequencies of small substrates (particularly sand and coarse gravel). Within Tobin Harbor, brook trout were associated with midembayment habitat and species assemblages, especially those locations with a mixture of sand, gravel, and cobble substrates, an absence of bedrock, and the presence of round whitefish, white sucker, and trout‐perch. Comparison of embayments with the model, Tobin Harbor, showed that six embayments without brook trout had very similar arrays of habitat. However, four embayments with brook trout had relatively different arrays of habitat from Tobin Harbor. These results suggest that there is potential for further recovery of brook trout populations across Isle Royale nearshore habitats.
Avaliação da ressecção hepática em pacientes cirróticos com carcinoma hepatocelular
Authors: Silva Maurício , Mattos Angelo Alves de , Fontes Paulo Roberto Ott , Waechter Fábio Luiz , Pereira-Lima Luiz
Published: July 2008

RACIONAL: O carcinoma hepatocelular é uma complicação que acomete pacientes que apresentam cirrose hepática. A ressecção hepática, o transplante ortotópico de fígado e a ablação percutânea constituem opções terapêuticas com o intuito curativo. OBJETIVO: Avaliar os resultados da ressecção hepática para o tratamento do carcinoma hepatocelular, em fígados cirróticos, em um hospital geral. MÉTODOS: Foram avaliadas as características clínicas, laboratoriais, endoscópicas e histopatológicas de 22 pacientes submetidos a ressecção hepática entre os anos de 1996 e 2005, com o intuito de se avaliar a sobrevida, a identificação de fatores prognósticos e a incidência de recidiva tumoral. Para tanto, especial atenção foi dada aos níveis séricos de bilirrubinas e alfa-fetoproteína, grau de disfunção hepatocelular (avaliado pelas classificações Child-Pugh-Turcotte e " Model for End-Stage Liver Disease" - MELD), tamanho e número de tumores, invasão microvascular e presença de lesões satélites. O nível de significância utilizado foi de 95% na análise estatística. RESULTADOS: A média de idade dos pacientes estudados foi de 62,09 anos, sendo 17 do sexo masculino. Em 10 casos a cirrose hepática esteve associada à infecção crônica pelo vírus da hepatite C, em 4 à combinação do uso crônico do etanol e vírus da hepatite C, em 3 ao vírus da hepatite B, em 2 ao uso do etanol isoladamente, em 1 com uso de medicamentos e, em 2 casos, não foi identificada a causa. Dezoito pacientes apresentaram tumor único, sendo que em 11 o tumor media menos que 5 cm. A sobrevida variou entre 10 dias e 120 meses, com média de 33,5 meses. No final do 1º, 3º e 5º anos, identificou-se sobrevida de 61,90%, 16,67% e 11,11%, respectivamente. Houve três óbitos nos primeiros 3 meses posteriores à ressecção hepática. Treze óbitos foram identificados após os primeiros 3 meses, sendo que 12 casos foram relacionados à recidiva e progressão da neoplasia. Um paciente faleceu no período pós-operatório imediato de novo procedimento cirúrgico para ressecção de uma recidiva tumoral. No que se refere à sobrevida e à identificação de fatores prognósticos, foi identificada relação entre sobrevida e invasão microvascular. Não foi observada diferença, com significância estatística, nas curvas de sobrevida entre os níveis séricos de bilirrubinas e alfa-fetoproteína, grau de disfunção hepatocelular, tamanho e número de lesões. Entretanto, foi identificada probabilidade de recidiva tumoral maior no grupo de pacientes que apresentava invasão microvascular no estudo histopatológico. CONCLUSÃO: Apesar do pequeno número de pacientes estudados, observaram-se maus resultados com o tratamento cirúrgico do carcinoma hepatocelular. A seleção adequada dos casos pode ser fator importante para a melhoria desse resultado.
Complicações imediatas e tardias após cirurgia de reservatório ileal na polipose adenomatosa familiar
Authors: Leal Raquel Franco , Ayrisono Maria de Lourdes Setsuko , Coy Cláudio Saddy Rodrigues , Fagundes João José , Góes Juvenal Ricardo Navarro
Published: July 2008

RACIONAL: A retocolectomia total com confecção de reservatório ileal é cirurgia ideal para o tratamento do cólon e reto dos doentes com polipose adenomatosa familiar, no entanto pode estar associada a complicações no pós-operatório imediato e tardio. OBJETIVO: Estudar as complicações pós-operatórias da cirurgia do reservatório ileal na polipose adenomatosa familiar. MÉTODOS: Estudo retrospectivo de 69 doentes com polipose adenomatosa familiar submetidos a cirurgia de reservatório ileal no período de 1984 a 2006, pelo Grupo de Coloproctologia da Faculdade de Ciências Médicas da Universidade Estadual de Campinas, SP. O seguimento médio pós-operatório foi de 82 (2-280) meses. Dados de interesse: ocorrência de complicações no pós-operatório. RESULTADOS: A morbidade e mortalidade foram de 63,8% e 2,9%, respectivamente. As complicações mais freqüentes foram obstrução intestinal (17,4%), estenose da anastomose (15,9%) e sepse pélvica (10,1%). Outras complicações foram isquemia aguda do reservatório ileal (4,3%), ileíte do reservatório (" pouchitis" ) (2,9%) e fístulas relacionadas ao reservatório (2,9%). CONCLUSÕES: A morbimortalidade foi semelhante à da literatura e aceitável para uma cirurgia complexa como é a do reservatório ileal, realizada em dois tempos operatórios. A obstrução intestinal foi a complicação mais freqüente. Entretanto, isquemia do reservatório, " pouchitis" e sepse pélvica constituíram importantes complicações relacionadas à perda do reservatório ileal.
Diarréia nosocomial em unidade de terapia intensiva: incidência e fatores de risco
Authors: Borges Sérvulo Luiz , Pinheiro Bruno do Valle , Pace Fabio Heleno de Lima , Chebli Julio Maria Fonseca
Published: July 2008

RACIONAL: Diarréia nosocomial parece ser comum em unidades de terapia intensiva, embora sua epidemiologia seja pouco documentada em nosso meio. OBJETIVO: Determinar a incidência e fatores de risco de diarréia entre pacientes adultos internados em unidade de terapia intensiva. MÉTODOS: Foram incluídos prospectivamente 457 pacientes no período entre outubro de 2005 e outubro de 2006. Dados demográficos, clínicos e bioquímicos, bem como aspecto e número de evacuações eram registrados diariamente até a saída do paciente do setor. RESULTADOS: Diarréia ocorreu em 135 (29,5%) pacientes, durando em média 5,4 dias. O tempo do seu início em relação à internação foi de 17,8 dias e casos similares de diarréia no mesmo período foram registrados em 113 (83,7%) pacientes. A mortalidade hospitalar foi maior nos pacientes com diarréia do que naqueles sem esta intercorrência. Na análise multivariada através de modelo de regressão logística, apenas o número de antibióticos (OR 1,65; IC 95% = 1,39-1,95) e o número de dias de antibioticoterapia (OR 1,16; IC 95% = 1,12-1,20) associaram-se estatisticamente com a ocorrência de diarréia. Cada dia de acréscimo a mais da antibioticoterapia aumentou em 16% o risco de diarréia (IC 12% a 20%), enquanto a adição de um antibiótico a mais ao esquema antimicrobiano aumentou as chances de ocorrência de diarréia em 65% (IC 39% a 95%). CONCLUSÃO: A incidência de diarréia nosocomial na unidade de terapia intensiva é elevada (29,5%). Os principais fatores de risco para sua ocorrência foram número de antibióticos prescritos e duração da antibioticoterapia. Além das precauções entéricas, a prescrição judiciosa e limitada de antimicrobianos, provavelmente reduzirá a ocorrência de diarréia neste setor.
Prevalence of rectoanal inhibitory reflex in chagasic megacolon
Authors: Cavenaghi Simone , Felicio Otaviano Cardoso da Silva , Ronchi Luis Sergio , Cunrath Geni Satomi , Melo Marcelo Maia Caixeta de , Netinho João Gomes
Published: July 2008

BACKGROUND: Rectoanal inhibitory reflex is not always evident in patients with chagasic megacolon. This may be due to insufficient volumes of air used during insufflation for the manometric examination. AIMS: To identify the volume of air necessary to induce rectoanal inhibitory reflex in patients with chagasic megacolon and to observe its prevalence in these individuals. METHODS: Rectoanal inhibitory reflex in 39 patient with chagasic megacolon was studied by means of anorectal manometry using the balloon method. The balloon was insufflated using sequential volumes up to 300 mL to induce reflex. RESULTS: Rectoanal inhibitory reflex was identified in 43.6% of the patients using a mean volume of 196 mL of insufflated air (standard error = 13.5). CONCLUSION: Rectoanal inhibitory reflex can be induced in patients with chagasic megacolon when greater volumes of air are used.
Decrease in prevalence of Helicobacter pylori infection during a 10-year period in Brazilian children
Authors: Kawakami Elisabete , Machado Rodrigo Strehl , Ogata Silvio Kazuo , Langner Marini
Published: July 2008

BACKGROUND: Decreasing prevalence of H pylori infection has been reported in some countries. AIM: To evaluate the prevalence of Helicobacter pylori infection in a 10-year period in children submitted to upper digestive endoscopy. METHODS: It was a retrospective observational study. The records of 1,165 endoscopies performed during a 10-year period in a public hospital of the City of São Paulo, SP, Brazil, in patients up to 18-year-old. Only the first endoscopy was considered. Helicobacter pylori infection was defined by the rapid urease test, performed with one fragment of antral mucosa. Chi-square for trend has been estimated to compare Helicobacter pylori prevalence across the period. RESULTS: The main indication for endoscopy was epigastric pain (47.4%). There were 392 patients with H pylori infection (33.6%), 12.8% being infants, 19.4% toddlers, 28.8% schoolchildren and 46.3% adolescents. Prevalence was 60.47% in the first year of the study and 30.43% in the last. Among the less than 6-year-old patients there was a decrease in infection prevalence from 25% for the 1993-6 period to 14.3% in the 2000-02 period, while among the over 12-year-old patients the decrease was from 55.5% in the first period to 39.6% in the latter. The decrease in H pylori infection prevalence was more intense within patients with epigastric pain, in which prevalence has decreased from 48.2% (92/191) in 1993-6, to 41.9% (65/155) in 1997-9 and 27.7% (57/206) in 2000-02. CONCLUSION: The study suggests a significant decrease in the prevalence of H pylori infection regarding the studied patients. The trend was mainly observed in the younger age group and in patients with epigastric pain.
Role of N-acetylcysteine on fibrosis and oxidative stress in cirrhotic rats
Authors: Pereira-Filho Gustavo , Ferreira Clarissa , Schwengber Alex , Marroni Cláudio , Zettler Cláudio , Marroni Norma
Published: July 2008

BACKGROUND: Hepatic cirrhosis is the final stage of liver dysfunction, characterized by diffuse fibrosis which is the main response to the liver injury. The inhalatory carbon tetrachloride is an effective experimental model that triggers cirrhosis and allows to obtain histological and physiological modifications similar to the one seen in humans. AIM: To investigate the effects of N-acetylcysteine (NAC) on the fibrosis and oxidative stress in the liver of cirrhotic rats, analyzing liver function tests, lipoperoxidation, activity of glutathione peroxidase enzyme, collagen quantification, histopathology, as well as the nitric oxide role. METHODS: The animals were randomly in three experimentals groups: control (CO); cirrhotic (CCl4) and CCl4 + NAC. Evaluate the lipid peroxidation, the glutathione peroxidase enzyme, the collagen and the expression of inducible nitric oxide synthase (iNOS). RESULTS: The cirrhotic group treated with N-acetylcysteine showed trough the histological analysis and collagen quantification lower degrees of fibrosis. This group has also shown less damage to the cellular membranes, less decrease on the glutathione peroxidase levels and less expression of inducible nitric oxide synthase when matched with the cirrhotic group without treatment. CONCLUSION: N-acetylcysteine seams to offer protection against hepatic fibrosis and oxidative stress in cirrhotic rat livers.
Apendagite epiplóica: aspectos clínicos e radiológicos
Authors: Freitas Gustavo Pignaton de , Borges Adriana de Almeida , Mendonça Renato , Ribeiro Cláudia , Chindamo Maria Chiara
Published: July 2008

Apendagite epiplóica é uma doença inflamatória abdominal incomum. Foram avaliados, retrospectivamente, os prontuários de 44 pacientes com diagnóstico de apendagite epiplóica atendidos no Hospital Barra D’Or, Rio de Janeiro, RJ, no período entre fevereiro de 2005 e setembro de 2006, sendo 82% homens e 18% mulheres, com média de idade de 44,7 anos. Buscou-se caracterizar o quadro clínico-laboratorial e radiológico desses pacientes. As alterações laboratoriais mais freqüentes foram piúria e leucocitose, cada uma presente em 5% dos casos. O diagnóstico foi feito por tomografia computadorizada de abdome com achado de lesão ovóide em cólon descendente em 52% dos pacientes. A resolução do quadro clínico foi obtida com tratamento conservador.
Infecções parasitárias do apêndice cecal e suas relações com apendicite aguda
Authors: Silva Danielle Fernandes da , Silva Reinaldo José da , Silva Márcia Guimarães da , Sartorelli Alesso Cervantes , Takegawa Bonifácio Katsunori , Rodrigues Maria Aparecida Marchesan
Published: July 2008

Investigou-se a prevalência de infecções parasitárias do apêndice cecal e suas relações com a apendicite. Dos 1.600 apêndices estudados 24 (1,5%) apresentaram infecção parasitária. Enterobius vermicularis foi encontrado em 23 casos (95,8%) e Taenia sp em apenas um (4,2%). Dezesseis pacientes (66,7%) eram menores de 10 anos; 15 eram masculinos e 9 femininos. A análise histopatológica demonstrou inflamação aguda supurativa em 12 casos (50%), eosinofilia em 13 (54,2%) e hiperplasia linfóide em 10 (41,7%). Complicações como peritonite ocorreram em 11 e gangrena em 3 casos. As infecções parasitárias do apêndice são causa pouco freqüente de apendicite aguda em crianças e adolescentes.