bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human metabolic interactions of environmental chemicals
Authors: Hodgson Ernest , Rose Randy L. 
Published: August 2007

AbstractInvestigations utilizing recombinant human xenobiotic‐metabolizing enzymes as well as human hepatocytes have revealed a number of interactions not only between different environmental chemicals (ECs) but also between ECs and endogenous metabolites. Organophosphorus insecticides (OPs) are potent inhibitors of the human metabolism of carbaryl, carbofuran, DEET and fipronil, as well as the jet fuel components, nonane and naphthalene. OPs are potent irreversible inhibitors of testosterone metabolism by cytochrome P450 (CYP) 3A4 and of estradiol metabolism by CYP3A4 and CYP1A2. All of these CYP inhibitions are believed to be due to the release of reactive sulfur during CYP‐catalyzed oxidative desulfuration. It has also been shown that the esterase(s) responsible for the initial step in permethrin metabolism in human liver is inhibited by both chlorpyrifos oxon and carbaryl. A number of pesticides, including chlorpyrifos, fipronil and permethrin, and the repellent, DEET, have been shown to be inducers of CYP isoforms in human hepatocytes, with fipronil being the most potent. Several agrochemicals, including fipronil and the pyrethroids, permethrin and deltamethrin, show toxicity toward human hepatocytes with fipronil being the most potent in this regard. Endosulfan‐α, which has shown promise as a model substrate for phenotyping CYP3A4 and CYP2B6 in human liver microsomes, is also an inducer of CYP2B6, acting through the PXR receptor. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:182–186, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20175
Genetic variability in the cytochrome P450–paraoxonase 1 (PON1) pathway for detoxication of organophosphorus compounds
Authors: Furlong Clement E. 
Published: August 2007

AbstractDetoxication of organophosphorus (OP) compounds is affected by genetic and environmental modulation of a number of enzymes involved in the process. For organophosphorothioate insecticides, different P450 isozymes and variants carry out two reactions that have quite different consequences; (1) they bioactivate their parent compounds to highly toxic oxon forms that are many times more toxic than the parent compounds, and (2) concurrently, they dearylate the parent OP compounds, generating much less toxic metabolites. The ratios at which these different P450s carry out bioactivation versus dearylation differ among the P450 isozymes. The detoxication of the oxon forms of diazinon and chlorpyrifos is achieved by hydrolysis to the respective aromatic alcohols and diethyl phosphates primarily by paraoxonase 1 (PON1), a plasma enzyme tightly associated with high‐density lipoprotein particles and also found in liver. Stoichiometric binding to other targets also contributes to the detoxication of these oxons. PON1 is polymorphically distributed in human populations with an amino acid substitution (Gln/Arg) at position 192 of this 354‐amino acid protein (the initiator Met residue is cleaved on maturation) that determines the catalytic efficiency of hydrolysis of some substrates. In addition to the variable catalytic efficiency determined by the position 192 amino acid, protein levels of PON1 vary by as much as 15‐fold among individuals with the same PON1192genotype (Q/Q; Q/R; R/R). The generation of PON1 null mice and transgenic mice, expressing each of the human PON1192alloforms in place of mouse PON1, has allowed for the examination of the physiological function of the PON1192alloforms in OP detoxication. Sensitivity to diazoxon exposure is primarily determined by the plasma level of PON1, whereas for chlorpyrifos oxon exposure, both the plasma PON1 level and the position 192 amino acid are important—PON1R192is more efficient in inactivating chlorpyrifos oxon than is PON1Q192. The availability of PON1 null mice provides an opportunity to examine the contribution of other enzymes in the OP detoxication pathways without PON1 interference. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:197–205, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20181
Reactive‐Injecting Follow‐Through Shaped Charges from Sequent‐Material Conical Liners
Authors: Schilling Thomas J. 
Published: August 2007

AbstractShaped charges using reactive‐metal liners have the potential for beyond‐penetration effects, e.g. thermodynamic events that increase pressure in a volume adjacent to the penetration. Shaped charge liners made from a copper penetrating‐ and an aluminum reactive‐component in a sequent‐material configuration were compared in tests to baseline homogeneous copper liners. Copper lined shaped charges had greater mild steel penetration performance, but lacked beyond‐penetration pressurization effects exhibited by the sequent‐material lined units. Jet capture experiments, beyond‐penetration constant‐volume tests, and thermochemical equilibrium calculations provide evidence supporting the aluminum slug comminution into unoxidized reactive fuel, augmenting beyond‐penetration effects.
Theoretical Prediction of Heats of Sublimation of Energetic Materials Using Pseudo‐Atomic Orbital Density Functional Theory Calculations
Authors: Hu Anguang , Larade Brian , Dudiy Sergey , Abou‐Rachid Hakima , Lussier Louis‐Simon , Guo Hong 
Published: August 2007

AbstractWe present a predictive model for the heats of sublimation of the condensed phases of energetic materials that combine the empirical relations of Politzer with first‐principles density‐functional calculations of the electronic properties of the molecular surfaces. The distinct features of our methodology are the use of numerical pseudo‐atomic orbitals for the quantum mechanical calculation of the electronic charge density, as well as an improved technique for the molecular surface area determination. As applications, we used our model to predict heats of sublimation of energetic molecules CL‐20, HMX, RDX, TNT, FOX‐7, TATB, and LLM‐105, with the Politzer parameters fit based on a set of eight nitro‐aromatic molecules. In comparison with conventional quantum chemistry calculations, our approach is tremendously less computationally demanding, yet it still demonstrates competitive accuracy and predictive power.
Outcome of Segmental Gastrectomy versus Distal Gastrectomy for Early Gastric Cancer
Authors: Ishikawa Koichi , Arita Tsuyoshi , Ninomiya Shigeo , Bandoh Toshio , Shiraishi Norio , Kitano Seigo 
Published: August 2007

AbstractBackgroundBecause of the frequent occurrence of postgastrectomy disturbances after distal gastrectomy (DG), segmental gastrectomy (SG) has recently been applied to early gastric cancer (EGC). Outcomes of SG and DG in patients with EGC were compared to clarify the usefulness of SG as a treatment for EGC.MethodsThis retrospective study involved 61 patients with EGC: 28 patients who underwent DG before March 1996 and 33 patients who underwent SG after April 1996 during the period April 1991 through March 2002. Patient and tumor characteristics, operative results, and postoperative outcomes were compared between the two groups.ResultsThe postoperative/preoperative body weight ratio was higher in the SG group than in the DG group. Early dumping syndrome and reflux gastritis occurred less frequently after SG than after DG. The incidence of postoperative complications was similar in the two groups. All patients remained alive without recurrence during a mean follow‐up period of 54.7 months in the SG group and 99.9 months in the DG group.ConclusionsIn comparison to DG, SG is associated with improved postoperative quality of life with no decrease in operative curability of EGC. Thus, SG is a feasible treatment for EGC.
Effects of different management regimes on aquatic macroinvertebrate diversity in Australian rice fields
Authors: Wilson A. L. , Watts R. J. , Stevens M. M. 
Published: August 2007

AbstractThe maintenance of invertebrate diversity within agricultural environments can enhance a number of agronomically important processes, such as nutrient cycling and biological pest control. However, few Australian studies have been undertaken which specifically address the effects of commercial management regimes on rice field biodiversity. In this study, we compared aquatic macroinvertebrate communities within Australian rice fields cultivated under three commercial management regimes: conventional‐aerial (agrochemicals applied, aerially sown), conventional‐drill (agrochemicals applied, directly drill‐sown) and organic‐drill (agrochemical‐free, directly drill‐sown). These comparisons were undertaken using a combination of community assessment approaches, including morphospecies richness, abundance, diversity and community composition. In general, greater biodiversity existed within macroinvertebrate communities that developed under organic management regimes than under conventional regimes (i.e., higher morphospecies richness and Shannon diversity). Although there were significant differences in several parameters across management regimes early in the rice‐growing season, as the growing season progressed the invertebrate communities that developed in the different management regimes became more similar. Only community composition analyses showed significant differences late in the growing season, with functional differences across aquatic faunal assemblages suggested by increased predator abundance in communities sampled from the organic management regime. In order to improve biodiversity within these aquatic environments, management techniques need to be examined individually and the most disruptive processes identified. Alternative management procedures can then be developed that minimise biodiversity loss whilst still delivering required agronomic outcomes.
Die Genetik atopischer Erkrankungen
Authors: Marenholz I. , Lee Y.-A. 
Published: August 2007

Zusammenfassung
Die atopischen Erkrankungen – atopische Dermatitis (AD), allergische Rhinokonjunktivitis und Asthma bronchiale – sind häufige, chronisch-entzündliche Erkrankungen der Haut und Atemwege, die oft mit Allergien (Bildung von spezifischen IgE-Antikörpern) gegen Umweltallergene assoziiert sind. Als komplexe genetische Erkrankungen werden sie sowohl durch genetische Faktoren als auch durch Umwelteinflüsse verursacht.
Bisherige Anstrengungen bei der Suche nach Krankheitsgenen zielten daher häufig auf die der Immunreaktion zugrunde liegenden Mechanismen ab. Jüngste Erfolge bei der Genidentifizierung belegen dagegen den großen Einfluss, den der epitheliale Barrieredefekt auf die Ätiologie von AD und Asthma hat. Sie stellen einen wichtigen Meilenstein bei der Aufdeckung der genetischen Ursachen dieser komplexen Erkrankungen dar und ermöglichen eine neue Sicht auf die molekularen Mechanismen, die zur Krankheitsentstehung führen. Darüber hinaus können sie wegweisend für die Entwicklung neuer Behandlungs- und Präventionsstrategien sein.
Relation of Depression, Natural Killer Cell Function, and Infections after Coronary Artery Bypass in Women
Authors: Doering Lynn V. , Martínez-Maza Otoniel , Vredevoe Donna L. , Cowan Marie J. 
Published: August 2007

Background: After hospital discharge for coronary artery bypass grafting (CABG), infection is a common cause of morbidity. Although depression has been associated with immune dysfunction, its role in post-CABG infection is unknown. Aims: The purpose of this study was to: 1) compare natural killer cell cytotoxicity (NKCC) and post-hospitalization infections in depressed and non-depressed women after CABG; and 2) test whether NKCC mediated the relationship between post-discharge depression and infections. Methods: Sixty-seven women recovering from CABG were assessed for depression prior to hospital discharge and followed for six months. Major depression was identified by a structured clinical interview. Infections were identified by patient report using the Modified Health Review and by medical chart audit. Results: Compared to non-depressed women after CABG, women with major depression had reduced NKCC, more all-cause infections, and more self-reported illnesses. Although NKCC did not mediate the relationship between depression and wound (i.e. incisional) infections after CABG, it did mediate the relationship between depression and non-wound infections, including pneumonias and upper respiratory infections. Conclusions: For the first six months after CABG, women with major depression are at increased risk for infections. Natural killer cell cytotoxicity may be related to this phenomenon, particularly to non-wound infections.
Proteins of the malaria parasite sexual stages: expression, function and potential for transmission blocking strategies
Authors: PRADEL G. 
Published: August 2007

SUMMARYThe sexual phase of the malaria pathogen,Plasmodium falciparum, culminates in fertilization within the midgut of the mosquito and represents a crucial step in the completion of the parasite's life-cycle and transmission of the disease. Two decades ago, the first sexual stage-specific surface proteins were identified, among themPfs230,Pfs48/45, andPfs25, which were of scientific interest as candidates for the development of transmission blocking vaccines. A decade later, gene information gained from the sequencing of theP. falciparumgenome led to the identification of numerous additional sexual-stage proteins with antigenic properties and novel enzymes that putatively possess regulatory functions during sexual-stage development. This review aims to summarize the sexual-stage proteins identified to date, to compare their stage specificities and expression patterns and to highlight novel regulative mechanisms of sexual differentiation. The prospective candidacy of select sexual-stage proteins as targets for transmission blocking strategies will be discussed.
Cloning and characterization of an orphan seven transmembrane receptor from Schistosoma mansoni
Authors: PEARSON M. S. , McMANUS D. P. , SMYTH D. J. , JONES M. K. , SYKES A. M. , LOUKAS A. 
Published: August 2007

SUMMARYA partial cDNA sequence was obtained from the human blood fluke, Schistosoma mansoni using a signal sequence trap approach. The full-length cDNA was cloned and termed Sm-7TM. The corresponding open reading frame had 7 membrane spanning domains and shared identity with a small, novel group of seven transmembrane (7TM) receptors from vertebrates and invertebrates, including the human ee3 receptor – a heptahelical protein implicated in neuronal signalling. Phylogenetic analysis of this novel family showed that the Sm-7TM ORF formed a clade with exclusively invertebrate sequences. Based on topology modelling with ee3, Sm-7TM was predicted to possess an intracellular C-terminal tail, which was expressed as a soluble thioredoxin fusion protein (Sm-7TMC) in Escherichia coli and purified using metal ion-affinity chromatography. A polyclonal antiserum against this domain was used to detect Sm-7TM in detergent-soluble parasite extracts and to immunolocalize the receptor to the tegument of adult S. mansoni.
Biotic and abiotic predictors of tick (Dermacentor variabilis) abundance and engorgement on free-ranging raccoons (Procyon lotor)
Authors: MONELLO R. J. , GOMPPER M. E. 
Published: August 2007

SUMMARYWe examined the relative importance of abiotic and biotic factors on the ability of adultDermacentor variabilisticks to attach and engorge with blood across 10 populations of free-ranging raccoons (Procyon lotor). We developeda priorimodels that represented explicit hypotheses based on the literature and tested the ability of these models to explain non-replete and replete (fully engorged with blood) tick infestation using generalized linear models and Akaike's Information Criterion. Abiotic models that included month and site of collection clearly provided a better fit for non-replete tick abundance data, while biotic models with host age and sex covariates best fit the replete tick data. Abiotic models of non-replete abundance were superior to biotic models because of large seasonal and site fluctuations in non-replete abundance that masked differences due to host characteristics. Conversely, best-fitting models of replete tick abundance included only age and sex and suggest that once a tick has reached a host, host-parasite interactions are the primary determinant of engorgement by female ticks. Host population structure may have a large influence on potential cohort size of ticks by reducing or increasing the total number and proportion that can become engorged and moult or lay eggs.
Bifurcations of stationary measures of random diffeomorphisms
Authors: ZMARROU HICHAM , HOMBURG ALE JAN 
Published: August 2007

AbstractRandom diffeomorphisms with bounded absolutely continuous noise are known to possess a finite number of stationary measures. We discuss the dependence of stationary measures on an auxiliary parameter, thus describing bifurcations of families of random diffeomorphisms. A bifurcation theory is developed under mild regularity assumptions on the diffeomorphisms and the noise distribution (e.g. smooth diffeomorphisms with uniformly distributed additive noise are included). We distinguish bifurcations where the density function of a stationary measure varies discontinuously or where the support of a stationary measure varies discontinuously. We establish that generic random diffeomorphisms are stable. The densities of stable stationary measures are shown to be smooth and to depend smoothly on an auxiliary parameter, except at bifurcation values. The bifurcation theory explains the occurrence of transients and intermittency as the main bifurcation phenomena in random diffeomorphisms. Quantitative descriptions by means of average escape times from sets as functions of the parameter are provided. Further quantitative properties are described through the speed of decay of correlations as a function of the parameter. Random differentiable maps which are not necessarily injective are studied in one dimension; we show that stable one-dimensional random maps occur open and dense and that in one-parameter families bifurcations are typically isolated. We classify codimension-one bifurcations for one-dimensional random maps; we distinguish three possible kinds, the random saddle node, the random homoclinic and the random boundary bifurcation. The theory is illustrated on families of random circle diffeomorphisms and random unimodal maps.
On the existence of non-trivial homoclinic classes
Authors: BONATTI CHRISTIAN , GAN SHAOBO , WEN LAN 
Published: August 2007

AbstractWe show that, for C1-generic diffeomorphisms, every chain recurrent class C that has a partially hyperbolic splitting $E^s\oplus E^c\oplus E^u$ with dimEc=1 either is an isolated hyperbolic periodic orbit, or is accumulated by non-trivial homoclinic classes. We also prove that, for C1-generic diffeomorphisms, any chain recurrent class that has a dominated splitting $E\oplus F$ with dim(E)=1 either is a homoclinic class, or the bundle E is uniformly contracting. As a corollary we prove in dimension three a conjecture of Palis, which announces that any C1-generic diffeomorphism is either Morse–Smale, or has a non-trivial homoclinic class.
Routine Histologic Examination is Unnecessary for Tonsillectomy or Adenoidectomy
Authors: Randall David A. , Martin Peter J. , Thompson Lester D. R. 
Published: August 2007

AbstractObjective: To determine whether the current practice and incurred cost of histologic examination of tonsillectomy and adenoidectomy specimens is warranted.Study Design: Review article based on medical literature.Subjects and Methods: A retrospective PubMed review of all pertinent literature regarding tonsillectomy, adenoidectomy, and related surgical pathology was conducted. References of the articles obtained were reviewed for additional sources.Results: Twenty studies report 54,901 patients and found 54 malignancies (0.087% prevalence). Of these, 48 (88% of the patients) had suspicious features such as tonsillar asymmetry, cervical lymphadenopathy, or abnormal tonsil appearance, preoperatively. The remaining six patients without any suspicious features (better representing true occult malignancy) were 0.011% of the total cases.Conclusion: Submission of tonsillectomy, adenoidectomy, or both specimens is warranted only when patients demonstrate findings associated with malignancy: tonsillar asymmetry, history of cancer, neck mass, tonsil firmness or lesion, weight loss, and constitutional symptoms.
Incidence and Significance of Myocardial Injury After Surgical Treatment of Head and Neck Cancer
Authors: Nouraei S. A. Reza , Al‐Yaghchi Chadwan , Sandhu Guri S. , Giussani Dino A. , Doyle Patrick , Clarke Peter M. 
Published: August 2007

AbstractObjective/Hypothesis: To review the incidence of, and risk factors for myocardial injury after head and neck surgery to help optimize patient care and develop perioperative cardioprotective strategies.Study Design: Observational cohort study.Methods: Records of 65 patients surgically treated for upper aerodigestive tract squamous cell carcinoma between 2005 and 2006 were reviewed. Information about cardiovascular history, tumor characteristics, details of surgery, and postoperative complications were recorded. Patients had troponin assays on the third postoperative day. Logistic regression was used to identify risk factors for postoperative myocardial injury.Results: The average age at presentation was 62 ± 12 years. There were 46 (71%) males and 19 (29%) females. Troponin‐positive and ‐negative groups were matched for age, sex, cardiovascular risks, comorbidity, site, tumor‐node‐metastasis status, and duration of the operations. Sixteen (25%) patients had postoperative myocardial injury including five clinical myocardial infarctions. Factors identified as independent predictors of postoperative myocardial injury were blood pressure level (odds ratio [OR] 1.17; 95% confidence interval [CI] 1.04–1.31; P < .02), intraoperative heart rate variability (OR 1.33; 95% CI 1.04–1.71; P < .02), and the degree of postoperative inflammatory response (OR 1.07; 95% CI 1.02–1.13; P < .001).Conclusions: Postoperative myocardial injury is a known independent predictor of cardiovascular prognosis. Its incidence in head and neck patients could potentially be reduced through stringent blood pressure management, tight intraoperative heart rate control, and dampening of the postoperative inflammatory response. Troponin testing is a valuable screening tool, and patients who have elevated levels postoperatively should be closely monitored and referred to a cardiologist for optimization of cardiovascular care.