bluuebunny/crossref_metadata_2025 huggingface dataset:
The Cochrane Library and mother‐to‐child transmission of HIV: an umbrella review
Authors: Bond Ken , Horvath Tara , Harvey Krystal , Wiysonge Charles Shey , Read Jennifer S.
Published: April 2007

Background

The majority of HIV‐infected children acquire the infection from their mothers. Preventing mother‐to‐child transmission (MTCT) of HIV is a key step in reducing the number of paediatric HIV infections.

Objective

To summarize the Cochrane reviews which have assessed the efficacy of interventions to prevent MTCT of HIV.

Methods

The Cochrane Database of Systematic Reviews was searched for any intervention to prevent MTCT of HIV. Data were extracted in duplicate and the GRADE assessment tool used to analyze the quality of extracted data.

Main Results

Five reviews met our inclusion criteria, and were of medium to high quality. One review examined the efficacy of antiretroviral prophylaxis for preventing MTCT of HIV. Each regimen used, ranging from the two‐dose nevirapine regimen to combination regimens, such as zidovudine and lamivudine, reduced the risk of MTCT of HIV. A meta‐analysis was not conducted as different regimens were used in the different trials. Caesarean section before labour and before ruptured membranes reduces the risk of MTCT of HIV (risk ratio [RR] 0.34, 95% confidence interval [CI] 0.14 to 0.8) compared to vaginal delivery. There was no evidence that vaginal disinfection (RR 0.94; 95%CI: 0.71 to 1.25), vitamin A supplementation (RR 1.10; 95%CI: 0.95 to 1.26), or hyperimmune HIV immunoglobulin (RR 0.67; 95%CI: 0.29 to 1.55) are efficacious interventions for the prevention of MTCT of HIV. There was no review on alternatives to breastfeeding.

Authors' Conclusions

Antiretroviral prophylaxis and caesarean section before labour and before ruptured membranes are efficacious in reducing the risk of MTCT of HIV. However, there is a need for research directed at (1) simplifying antiretroviral regimens to facilitate adherence and to minimize toxicity for both mothers and infants, (2) assessing the long‐term impact of drug resistance on future treatment of HIV‐infected mothers and infants, and identifying regimens that are less likely to induce resistance, and (3) assessing the efficacy of caesarean section among HIV‐infected women with undetectable viral loads or who are receiving combination antiretroviral regimens. Copyright © 2007 John Wiley & Sons, Ltd.
Theoretical Studies of the Electronic Structure and Spectroscopic Properties of [Ru(Htcterpy)(NCS)3]3–
Authors: Li Ming‐Xia , Zhang Hong‐Xing , Zhou Xin , Pan Qing‐Jiang , Fu Hong‐Gang , Sun Chia‐Chung
Published: April 2007

The ground‐ and excited‐state structures of [Ru(Htcterpy)(NCS)3]3– (1H) (tcterpy = 4,4′,4″‐tricarboxy‐2,2′:6′,2″‐terpyridine) are optimized by the DFT and CIS methods, respectively. Absorption and emission spectra in the gas phase and in solution (ethanol and water) are predicted at the TD‐DFT/B3LYP level. Experimental spectra are roughly reproduced by our calculated results. In ethanol solution, the HOMOs of the absorption spectra are dominated by d orbitals of the ruthenium atom and thiocyanate ligands, and the LUMOs possess π*(tcterpy) character with considerable carboxyl contribution. In the theoretically simulated absorption spectra, the first four bands are attributed to Ru/NCS→π*(tcterpy) charge‐transfer (MLCT/LLCT) transitions, whereas the fifth one with the strongest intensity arises from intraligand tcterpy π→π* charge transfer (ILCT) mixed with some O(pz)→terpy charge transfer (LLCT). Our calculations reveal that the MLCT/LLCT absorption bands in water are blue‐shifted with respect to those in ethanol, agreeing with experimental observations. This can be rationalized by a decreased dipole moment in the excited state. The phosphorescent emissions are calculated to occur at 724, 711, and 691 nm in the gas phase, in ethanol, and in water, respectively, all with the same 3LMCT/3LLCT character.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Mechanisms of H2, H2C=CH2, and O=CH2 Insertion into Cp2Zr(η2‐SiMe2=NtBu)(PMe3)
Authors: Bi Siwei , Zhu Shufen , Zhang Zhenwei
Published: April 2007

In this paper, the mechanisms for the insertion of H2, H2C=CH2, and O=CH2 into the Zr–Si bond of Cp2Zr(η2‐SiMe2=NtBu)(PMe3) (R) are theoretically investigated with the aid of density functional theory (DFT) calculations. The structure of the H2 insertion product P is discussed on the basis of our calculations, and its bonding features are rationalized in terms of molecular orbital theory. The regiochemistry for insertion of O=CH2 has also been theoretically investigated. It is found that the relative stabilities of the three insertion products of R are in the order P < P′ < P″. For the reactions of R with H2 and CH2=CH2, the rate‐determining steps are the insertions of H2 and CH2=CH2 into the Zr–Si bond of Cp2Zr(η2‐SiMe2=NtBu) (Int1), whereas PMe3 dissociation is the rate‐determining step for the reaction of R with O=CH2. Only the precursor Int2″, formed by the coordination of O=CH2 to the Zr atom, is located; those formed by the coordination of H2 and CH2=CH2 to Int1 are not found.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
The Aromatization of C5 Rings on a Heteronuclear Cluster
Authors: Tan Yong Leng Kelvin , Leong Weng Kee
Published: April 2007

The reaction of the heteronuclear cluster RuOs3(μ‐H)2(CO)13 with saturated and unsaturated C5 rings led to the aromatization of the rings to afford the clusters RuOs3(μ‐H)(CO)9(μ‐CO)2(η5‐C5R4R′). However, the reaction with cyclopentene gave the cluster RuOs3(μ‐H)3(CO)11(μ,η1:η2‐C5H7) via C–H activation of an sp2 carbon instead. Thermolysis of two of the products, RuOs3(μ‐H)(CO)9(μ‐CO)2(η5‐Cp′) and RuOs3(μ‐H)(CO)9(μ‐CO)2(η5‐C5H4SiMe3), led to their isomerization to butterfly clusters.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
The Thermal Decomposition of Three Magnetic Acetates at Their Autogenic Pressure Yields Different Products. Why?
Authors: Pol Swati V. , Pol Vilas G. , Felner Israel , Gedanken Aharon
Published: April 2007

We report on the one‐stage, reproducible, solvent‐free, competent and straightforward approach for the synthesis of fullerene‐like Ni@C, Co@C, and Fe3O4@C core‐shell nanostructures that can be scaled up. The single precursor reactions of low cost acetates of Fe, Co and Ni are separately conducted at a relatively low temperature (700 °C) in a closed Swagelok reactor, as compared to other methods for the formation of graphitic layers. It is worth mentioning that although identical reaction parameters are employed, using the three acetate precursors, the graphitic carbon is coated on nanosized metallic Ni and Co cores, while Fe tends to form Fe3O4, maintaining the same core‐shell morphology. The systematic morphological, compositional, structural characterization and the room temperature magnetic susceptibility measurements of the as‐made particles are carried out on a vibrating sample magnetometer. The plausible mechanism is based on the comparison between the dissociation products of three acetate precursors, their obtained experimental data, and calculations on the enthalpy and free energy changes.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Solvent‐Free, One‐Pot Synthesis of β‐Lactams by the Sc(OTf)3‐Catalyzed Reaction of Silyl Ketene Thiocetals with Imines
Authors: Benaglia Maurizio , Cozzi Franco , Puglisi Alessandra
Published: April 2007

A solvent‐free, catalytic, one‐pot synthesis of β‐lactams is described. The reaction involves the reaction between silyl ketene thioacetals derived from 2‐pyridyl thioesters and imines at room temperature in the presence of catalytic amounts of Sc(OTf)3 and in the absence of solvent. Extension of this procedure to the synthesis of an enantiomerically pure azetidinone, a precursor of industrially relevant bioactive β‐lactams, is also reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
A steepness index unit volume flood hydrograph approach for sub‐daily flow disaggregation
Authors: Tan Kim‐Seong , Chiew Francis H. S. , Grayson Rodger B.
Published: April 2007

The estimation of sub‐daily flows from daily flood flows is important for many hydrological and hydraulic applications. Flows during flood events often vary significantly within sub‐daily time‐scales, and failure to capture the sub‐daily flood characteristic can result in an underestimation of the instantaneous flood peaks, with possible risk of design failure. It is more common to find a longer record of daily flow series (observed or modelled using daily rainfall series) than sub‐daily flow data. This paper describes a novel approach, known as the steepness index unit volume flood hydrograph approach, for disaggregating daily flood flows into sub‐daily flows that takes advantage of the strong relationship between the standardized instantaneous flood peak and the standardized daily flood hydrograph rising‐limb steepness index. The strength of this relationship, which is considerably stronger than the relationship between the standardized flood peak and the event flood volume, is shown using data from six rivers flowing into the Gippsland Lakes in southeast Australia. The results indicate that the steepness index unit volume flood hydrograph approach can be used to disaggregate modelled daily flood flows satisfactorily, but its reliability is dependent on a model's ability to simulate the standardized daily flood hydrograph rising‐limb steepness index and the event flood volume. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of aroclor 1248 and two pure PCB congeners on phospholipase D activity in rat renal tubular cell cultures
Authors: Santiago Mercedes Fernández , López‐Aparicio Pilar , Recio María N. , Pérez‐Albarsanz Miguel A.
Published: April 2007

This paper elucidates the effect of different polychlorinated biphenyls (PCBs) on the phospholipase D (PLD) activity in soluble and particulate fractions of rat renal proximal tubular culture cells. Treatment with Aroclor 1248 (a commercial PCB mixture) caused a marked increase in the activity of PLD in intact renal tubular cells. The PLD activity was increased by Aroclor 1248 in the particulate fraction while the enzyme activity was unaffected in the soluble fraction. This work also shows that PCB 153 (2,2',4,4',5,5'‐hexachlorobiphenyl, a di‐ortho‐substituted nonplanar congener) can increase the activity of PLD only in the particulate fraction. The exposure of cell cultures to PCB 77 (3,3',4,4'‐tetrachlorobiphenyl, a non‐ortho‐substituted planar congener) does not alter PLD activity. These results suggest that PCB effects are structure dependent. Therefore, in order to clarify the molecular mechanism of activation of PLD by PCBs, the contents of immunoreactive PLD were examined by immunoblot analysis. Renal tubular cells expressed a PLD protein of 120 kDa corresponding with the PLD1 mammalian isoform in both the particulate and the soluble fraction. Aroclor 1248, PCB 153, and PCB 77 do not induce changes in the levels of PLD protein. These data indicate that PCBs, particularly nonplanar congeners, increase PLD activity. Moreover, these changes could not be demonstrated in the enzyme content in rat renal tubular cell cultures. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:68–75, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20160
Inhibition of fipronil and nonane metabolism in human liver microsomes and human cytochrome P450 isoforms by chlorpyrifos
Authors: Joo Hyun , Choi Kyoungju , Rose Randy L. , Hodgson Ernest
Published: April 2007

Previous studies have established that chlorpyrifos (CPS), fipronil, and nonane can all be metabolized by human liver microsomes (HLM) and a number of cytochrome P450 (CYP) isoforms. However, metabolic interactions between these three substrates have not been described. In this study the effect of either coincubation or preincubation of CPS with HLM or CYP isoforms with either fipronil or nonane as substrate was investigated. In both co‐ and preincubation experiments, CPS significantly inhibited the metabolism of fipronil or nonane by HLM although CPS inhibited the metabolism of fipronil more effectively than that of nonane. CPS significantly inhibited the metabolism of fipronil by CYP3A4 as well as the metabolism of nonane by CYP2B6. In both cases, preincubation with CPS caused greater inhibition than coincubation, suggesting that the inhibition is mechanism based. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:76–80, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20161
A Mu‐class glutathione S‐transferase from gills of the marine shrimp Litopenaeus vannamei: Purification and characterization
Authors: Contreras‐Vergara Carmen A. , Valenzuela‐Soto Elisa , García‐Orozco Karina D. , Sotelo‐Mundo Rogerio R. , Yepiz‐Plascencia Gloria
Published: April 2007

Glutathione S‐transferases (GSTs) are a family of detoxifying enzymes that catalyze the conjugation of glutathione (GSH) to electrophiles, thereby increasing the solubility of GSH and aiding its excretion from the cell. In this study, a glutatione S‐transferase from the gills of the marine shrimp Litopenaeus vannamei was purified by affinity chromatography using a glutathione–agarose affinity column. GST was purified to homogeneity as judged by reducing SDS‐PAGE and zymograms. This enzyme is a homodimer composed of ∼25‐kDa subunits and identified as a Mu‐class GST based on its activity against 1‐chloro‐2,4‐dinitrobenzene (CDNB) and internal peptide sequence. The specific activity of purified GST was 440.12 μmol/(min mg), and the Km values for CDNB and GSH are very similar (390 and 335 μM, respectively). The intersecting pattern of the initial velocities of this enzyme in the Lineweaver–Burke plot is consistent with a sequential steady‐state kinetic mechanism. The high specific activity of shrimp GST may be related to a highly effective detoxification mechanism necessary in gills since they are exposed to the external and frequently contaminated environment. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:62–67, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20162
Increase in the toxic effects of Tl+ on isolated rat liver mitochondria in the presence of nonactin
Authors: Korotkov Sergey M. , Glazunov Vadim V. , Yagodina Olga V.
Published: April 2007

The effects of Tl+ ions on isolated rat liver mitochondria were studied in the presence of nonactin, a cyclic ionophore. Nonenergized rat liver mitochondria were increasingly swollen at an elevated concentration of Tl+ in the 160 mOsm medium containing 0–150 mM sucrose and 0–75 mM TlNO3 or 0–50 mM Tl acetate. On the contrary, mitochondria in experiments with nonactin were contracted in the medium with 5–25 mM Tl+ and were swollen only in the medium with 50–75 mM TlNO3 or 50 mM Tl acetate. State 4 respiration along with swelling of succinate‐energized mitochondria followed contraction after their deenergization was further enhanced at increasing concentration of Tl acetate in a medium containing nonactin. Regardless of the presence of nonactin, State 3 and 2,4‐dinitrophenol (DNP)‐stimulated respiration and the monoamine oxidase (MAO) activity were not affected in the medium with 0–25 mM Tl acetate and sucrose. DNP‐stimulated respiration decreased and the MAO activity somewhat increased in the medium containing 50 mM Tl acetate and nonactin. Uptake of 86Rb+ by energized mitochondria in the presence of valinomycin was considerably decreased when Tl+ and nonactin were simultaneously present in the medium. An increase of the toxic effect of Tl+ on rat liver mitochondria in the presence of nonactin is accounted for by disruption of mitochondria due to their more extensive swelling and uncoupling of mitochondria, resulting in the stimulation of State 4 and depletion of their energy store. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:81–91, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20163
MEK/ERK‐dependent uPAR expression is required for motility via phosphorylation of P70S6K in human hepatocarcinoma cells
Authors: Bessard Anne , Frémin Christophe , Ezan Frédéric , Coutant Alexandre , Baffet Georges
Published: April 2007

Motility and invasiveness events require specific intracellular signaling cascade activations. In cancer liver cells, one of these mechanisms could involve the MAPK MEK/ERK cascade activation which has been shown over expressed and activated in hepatocellular carcinoma. To study whether the MEK/ERK cascade is involved in the motility of HCC, we examined the effect of MEK inhibitor and ERK2 silencing using monolayer wound‐healing assays and fluoroblock invasion systems. Evidence was provided that the MAPK cascade is a key transduction pathway which controls HCC cells motility and invasiveness. We could disconnect proliferation to motility using mitomycin C and we established that RNAi‐mediated inhibition of ERK2 led to strongly reduced cell motility. To improve our understanding, we analysed the regulation and the role of urokinase receptor (uPAR) in this process. We provided evidence that uPAR was under a MEK/ERK dependent mechanism and blocking uPAR activity using specific antagonist or inhibiting its expression by RNA interference which resulted in complete inhibition of motility. Moreover, we found in MAPK inhibited cultures and in uPAR silencing cells that p70S6K phosphorylation on residue Thr‐389 was significantly reduced, whereas Ser‐421/Thr‐424 phosphorylation did not change. We highlighted that the FRAP/mTOR pathway did not affect motility and Thr‐389 phosphorylation. Furthermore, we demonstrated that p70S6K inhibition by RNA interference completely inhibited hepatocarcinoma cell motility. Therefore, targeting uPAR and/or MEK/ERK/S6K by RNA interference could be a major therapeutic strategy for the future treatment of invasive hepatocarcinoma cells. J. Cell. Physiol. 212: 526–536, 2007. © 2007 Wiley‐Liss, Inc.
D‐glucose stimulation of L‐arginine transport and nitric oxide synthesis results from activation of mitogen‐activated protein kinases p42/44 and Smad2 requiring functional type II TGF‐β receptors in human umbilical vein endothelium
Authors: Vásquez Rodrigo , Farías Marcelo , Vega José Luis , Martin Rody San , Vecchiola Andrea , Casanello Paola , Sobrevia Luis
Published: April 2007

Elevated extracellular D‐glucose increases transforming growth factor β1 (TGF‐β1) release from human umbilical vein endothelium (HUVEC). TGF‐β1, via TGF‐β receptors I (TβRI) and TβRII, activates Smad2 and mitogen‐activated protein kinases p44 and p42 (p42/44mapk). We studied whether D‐glucose‐stimulation of L‐arginine transport and nitric oxide synthesis involves TGF‐β1 in primary cultures of HUVEC. TGF‐β1 release was higher (∼1.6‐fold) in 25 mM (high) compared with 5 mM (normal) D‐glucose. TGF‐β1 increases L‐arginine transport (half maximal effect ∼1.6 ng/ml) in normal D‐glucose, but did not alter high D‐glucose‐increased L‐arginine transport. TGF‐β1 and high D‐glucose increased hCAT‐1 mRNA expression (∼8‐fold) and maximal transport velocity (Vmax), L‐[3H]citrulline formation from L‐[3H]arginine (index of NO synthesis) and endothelial NO synthase (eNOS) protein abundance, but did not alter eNOS phosphorylation. TGF‐β1 and high D‐glucose increased p42/44mapk and Smad2 phosphorylation, an effect blocked by PD‐98059 (MEK1/2 inhibitor). However, TGF‐β1 and high D‐glucose were ineffective in cells expressing a truncated, negative dominant TβRII. High D‐glucose increases L‐arginine transport and eNOS expression following TβRII activation by TGF‐β1 involving p42/44mapk and Smad2 in HUVEC. Thus, TGF‐β1 could play a crucial role under conditions of hyperglycemia, such as gestational diabetes mellitus, which is associated with fetal endothelial dysfunction. J. Cell. Physiol. 212:626–632, 2007. © 2007 Wiley‐Liss, Inc.
Acardiac syndrome coexisting with complex skeletal dysplasia in the co‐twin: 3D sonographic findings
Authors: Chen Chih‐Yao , Wu Yi‐Cheng , Chen Cheng‐Li , Yang Man‐Li
Published: April 2007

We present a case of twin reversed arterial perfusion syndrome complicated by an acardius acephalus fetus and complex skeletal dysplasia in the co‐twin, including a reduction of the right arm and absence of the right scapula and 4 ribs, as evaluated with three‐dimensional sonography and MRI. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007
Gonadal brucellar abscess: Imaging and clinical findings in 3 cases and review of the literature
Authors: Koc Zafer , Turunc Tuba , Boga Can
Published: April 2007

We report the cases of 3 patients with brucellar gonadal abscess who were examined with gray‐scale and color Doppler sonography. In these 3 cases, sonography revealed a thick‐walled avarian (n = 2) or testicular (n = 1) abscess. Duplex Doppler sonography indicated a low‐resistance type of flow in all 3 patients. The diagnosis of brucellar gonadal abscess is difficult, because it may have a misleading tumor‐like appearance. Awareness of the imaging findings of gonadal abscess in patients with brucellosis and correlation with the results of serologic testing can allow early diagnosis, especially in endemic areas. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007
Contexts and experimentalism in the psychology of Gabriele Buccola (1875–1885)
Authors: Degni Silvia , Foschi Renato , Lombardo Giovanni Pietro
Published: April 2007

Gabriele Buccola, since his untimely death, often has been mentioned as the first Italian psychologist who developed a strict program of laboratory research. Buccola, a Sicilian of Albanian ancestry, is a “case” in the history of Italian psychology. A self‐taught positivist, he established a relation with the major representatives of the European positivism. Kraepelin mentions him as one of the precursors of his project of applying experimental psychology to psychopathology. Buccola actually carried out research on the psychological, chemical‐biological, and psychopathological “modifiers” of reaction times, following an experimental program dealing mainly with the differential study both of basic and superior psychological processes, with mental hygiene ends. Historians of psychology agree in considering Buccola the first Italian laboratory psychologist to plan a program of research that was close to European psychological experimentalism.

The present article, starting from an outline of Buccola's role in the rising Italian scientific psychology, recontextualizes his experimentalism in an international sphere. This operation, which is carried out through a careful survey of Buccola's entire production—both theoretical and more properly scientific—is based on the search of the Darwinian, Spencerian, and Haeckelian evolutionist themes emerging from Buccola's program of research—a program that was influenced by the variegated European experimental panorama and characterized by the vision of science as a knowledge capable of transforming the nature of man and of society. © 2007 Wiley Periodicals, Inc.
Institutional variation in ordering complete blood counts for children hospitalized with bronchiolitis
Authors: Tarini Beth A. , Garrison Michelle M. , Christakis Dimitri A.
Published: April 2007

BACKGROUND

In the evaluation of infants with bronchiolitis there is little evidence to support the use of diagnostic testing, particularly complete blood counts (CBCs). However, the extent to which CBCs are ordered in the evaluation of infants with bronchiolitis is unknown.

OBJECTIVES

(1) To determine institutional variability in ordering of initial and repeat CBCs in infants hospitalized with bronchiolitis; (2) to examine the relationship between proportion of admissions with CBCs and mean hospital charges.

METHODS

We analyzed the Pediatric Health Information System database, which contains demographic and diagnostic data from 30 U.S. children's hospitals. We restricted our analysis to children less than 12 months old with a primary discharge diagnosis of bronchiolitis and an APR‐DRG of bronchiolitis/asthma. We performed multivariate ANOVA to examine variability in initial and repeat CBC ordering across hospitals, controlling for potential confounders. We used stratified logistic regression to determine which factors were associated with repeat CBCs. We examined the relationship between proportion of admissions with CBCs and mean hospital charges using t tests.

RESULTS

17,397 children were included in the analysis, and 48.2% had at least 1 CBC, whereas 7.8% had more than 1 CBC. The proportion of admissions with initial (23.2%‐70.2%) and repeat (0%‐18.6%) CBCs varied significantly across hospitals. Compared to those hospitals with the lowest proportion of admissions with CBCs, hospitals with higher proportions of CBCs had significantly higher mean hospital stay charges.

CONCLUSIONS

Given the potential downstream medical and financial consequences associated with CBC ordering in evaluation of infants with bronchiolitis, explanations for institutional variation warrant exploration. Journal of Hospital Medicine 2007;2:69–73. © 2007 Society of Hospital Medicine.
Reporting of estimated glomerular filtration rate: Effect on physician recognition of chronic kidney disease and prescribing practices for elderly hospitalized patients
Authors: Quartarolo Jennifer M. , Thoelke Mark , Schafers Stephen J.
Published: April 2007

BACKGROUND

Physician recognition of chronic kidney disease (CKD) in elderly patients has been noted to be poor. These patients are at increased risk of medication dosing errors and acute renal failure.

OBJECTIVE

To investigate the effect of reporting estimated glomerular filtration rate (GFR) of elderly hospitalized patients on physician recognition of CKD and physician prescribing behaviors.

DESIGN

A retrospective combined with a prospective medical record review project.

SETTING

A large academic medical center.

PATIENTS

Patients included were 65 years of age or older and had creatinine values within the normal laboratory range (< 1.6 mg/dL).

INTERVENTION

Reporting a calculated estimate of GFR to physicians.

MEASUREMENTS

Rates of recognition of CKD were examined before and after the intervention. The effects of the intervention on prescription of renal‐dosed antibiotics and nonsteroidal anti‐inflammatory drugs (NSAIDS) and cyclooxygenase‐ 2 inhibitors (COX‐2) at hospital discharge were assessed.

RESULTS

A total of 260 and 198 patients were included before and after the intervention, respectively. Recognition of chronic kidney disease was low in both groups but demonstrated a significant increase following reporting of estimated GFR (3.9% to 12.6%, P < .001). Reporting of GFR was not associated with a significant decrease in prescription of NSAID/COX‐2 medications or increased rates of correct dosing of antibiotics (P = .10 and P = .81, respectively).

CONCLUSIONS

Although reporting of estimated GFR was associated with improved physician recognition of CKD in elderly hospitalized patients, it did not lead to a change in physician prescribing. More extensive interventions are necessary to increase recognition and decrease medication dosing errors. Journal of Hospital Medicine 2007;2:74–78. © 2007 of Hospital Medicine.
QSAR of multiple mutated antibodies
Authors: Mandrika Ilona , Prusis Peteris , Yahorava Sviatlana , Tars Kaspars , Wikberg Jarl E.S.
Published: April 2007

The aim of this study was to develop predictive quantitative structure–activity relationship (QSAR) modeling for antibody‐peptide interactions. A small single chain antibody library was designed and manufactured around the murine anti‐p24 (HIV‐1) monoclonal antibody CB4‐1 by use of statistical molecular design (SMD) principles and site directed mutagenesis, and its affinity for a p24 derived antigen was determined by fluorescence polarization. A satisfactory QSAR model (Q2 = 0.74, R2 = 0.88) was derived by correlating the affinity data to physicochemical property scales of the amino acids varied in the library. The model explains most of the antibody–antigen interactions of the studied set, and provides insights into the molecular mechanism involved in antigen binding. Copyright © 2007 John Wiley & Sons, Ltd.
Identification of discontinuous antigenic determinants on proteins based on shape complementarities
Authors: Rapberger Ronald , Lukas Arno , Mayer Bernd
Published: April 2007

Diverse procedures for identifying antigenic determinants on proteins have been developed, including experimental as well as computational approaches. However, most of these techniques focus on continuous epitopes, whereas fast and reliable identification and verification of discontinuous epitopes remains barely amenable.

In this paper, we describe a computational workflow for the detection of discontinuous epitopes on proteins. The workflow uses a given protein 3D structure as input, and combines a per residue solvent accessibility constraint with epitope to paratope shape complementarity measures and binding energies for assigning antigenic determinants in the conformational context. We have developed the procedure on a given set of 26 antigen–antibody complexes with a known structure, and have further expanded the available paratope shapes by generating a virtual paratope library in order to improve the screening for candidate residues constituting discontinuous epitopes. Applying the workflow on the 26 given antigens with known discontinuous epitopes resulted in the correct identification of the spatial proximity of 12 antigen–antibody interaction sites. Combining solvent accessibility, shape complementarity and binding energies towards the identification of discontinuous epitopes clearly outperforms approaches solely considering accessibility and residue distance constraints. Copyright © 2007 John Wiley & Sons, Ltd.
An investigation into time domain Doppler modelling using the TLM numerical method
Authors: Scott I. J. G. , de Cogan D.
Published: April 2007

The effects observed by a moving source and stationary receiver, or conversely stationary source and moving receiver are well known to physicists. The Doppler effect as it is commonly known is recognized as a perceived change in frequency of the incident signal upon the receiver, caused by the motion of either the source or receiver with respect to the stationary component, occurring in both electromagnetic (transverse) and acoustic (longitudinal) waves. This paper will primarily focus on the acoustic Doppler effect in the time domain, simulating a variety of scenarios using transmission line matrix (TLM) modelling in which the effect can be observed, proceeding to compare the accuracy of the various models generated. A new technique to allow arbitrary placement of boundaries of a TLM mesh will also be introduced and analysed allowing accurate placement of the moving walls within the simulation. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of Camelina sativa expeller cake on performance and meat quality of broilers
Authors: Ryhänen Eeva‐Liisa , Perttilä Sini , Tupasela Tuomo , Valaja Jarmo , Eriksson Christian , Larkka Karita
Published: April 2007

The experiment was conducted to measure the effects of Camelina sativa expeller on the performance of broiler chickens and on the sensory quality and fatty acid composition of broiler meat. One‐day‐old broiler chickens were randomly allocated to the three dietary treatments which lasted 37 days. Experimental diets contained 0, 5 or 10% C. sativa expeller. Feed and water were offered ad libitum. The birds were weighed at the beginning, at 14 days and at the end of the trial at 37 days. Feed intake was recorded between weighings. C. sativa expeller reduced the growth of the birds linearly (P < 0.001). It also depressed their feed intake and feed conversion ratio during the starter phase (1–14 days). C. sativa did not cause any significant enlargement of the thyroid gland, nor were any liver lesions observed. Feeding of C. sativa significantly (P < 0.001) increased the omega‐3 fatty acid level in broiler meat. This was mainly due to an increase in α‐linolenic acid (18:3, n‐3). Feeding did not seem to have any adverse effect on the sensory quality of broiler meat. Meat from female broilers produced by feeding 5% C. sativa in the diet was significantly (P = 0.02) more tender than meat produced by feeding 10% C. sativa. Copyright © 2007 Society of Chemical Industry
Study of the oxidation of some catechols in the presence of 4‐amino‐3‐thio‐1,2,4‐triazole by digital simulation of cyclic voltammograms
Authors: Fotouhi Lida , Kiani Solmaz Taghavi , Nematollahi Davood , Heravi Majid M.
Published: April 2007

Electrochemical oxidation of catechol and its derivatives (1a–d) has been studied in the presence of 4‐amino‐3‐thio‐1,2,4‐triazole (3) at various pHs. Some electrochemical techniques such as cyclic voltammetry using the diagnostic criteria derived by Nicholson and Shain for various electrode mechanisms and controlled‐potential coulometry were used. Results indicate the participation of catechols (1a–d) with 3 in an intramolecular cyclization reaction to form the corresponding 1,2,4‐triazino[5,4‐b]‐1,3,4‐thiadiazine derivatives. In various scan rates, based on an electron transfer–chemical reaction–electron transfer–chemical reaction mechanism, the observed homogeneous rate constants (kobs) for Michael addition reaction were estimated by comparing the experimental cyclic voltammetric responses with the digital simulated results. The oxidation reaction mechanism of catechols (1a–d) in the presence of 4‐amino‐3‐thio‐1,2,4‐triazole (3) was also studied. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 340–345, 2007
Direct kinetics study of the product‐forming channels of the reaction of isoprene‐derived hydroxyperoxy radicals with NO
Authors: Patchen Amie K. , Pennino Michael J. , Kiep Annastassja C. , Elrod Matthew J.
Published: April 2007

A direct kinetics study of the product‐forming channels of the reaction of isoprene‐derived hydroxyalkylperoxy radicals with NO has been performed at 100 Torr pressure and 298 K using the turbulent flow technique with high‐pressure chemical ionization mass spectrometry for the detection of reactants and products. For comparative purposes, a similar study was also performed for the reaction of 1‐ and 2‐butene‐derived hydroxyalkylperoxy radicals with NO. The measured hydroxyalkylnitrate product channel branching ratios were determined to be 0.061, 0.068, and 0.070 for the 1‐butene, 2‐butene, and isoprene systems, respectively. The results are compared to previous measurements of the hydroxyalkylnitrate‐branching ratios for these systems, and the atmospheric significance of the results is discussed. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 353–361, 2007
Vascular Complications After Orthotopic Liver Transplantation After Neoadjuvant Therapy for Hilar Cholangiocarcinoma
Authors: Mantel Hendrik T.J. , Rosen Charles B. , Heimbach Julie K. , Nyberg Scott L. , Ishitani Michael B. , Andrews James C. , McKusick Michael A. , Haddock Michael G. , Alberts Steven R. , Gores Gregory J.
Published: April 2007

Liver transplantation after neoadjuvant chemoradiotherapy has emerged as an effective treatment for patients with localized, node-negative, unresectable hilar cholangiocarcinoma (CCA) or CCA arising in the setting of primary sclerosing cholangitis (PSC). However, concern has arisen regarding the potential for vascular complications due to high-dose neoadjuvant therapy before transplantation. We reviewed our experience with specific aims to determine the incidences of arterial, portal, and hepatic venous complications in patients transplanted for CCA compared with patients who undergo transplantation for other indications, and to describe patient outcome as a result of these vascular complications. We reviewed data for all patients who underwent liver transplantation for CCA between January 1993 and April 2006 and compared the incidences of vascular complications to whole organ and living donor recipient control groups. Sixty-eight patients underwent neoadjuvant therapy and subsequent liver transplantation. Arterial complications arose in 21%; portal venous complications arose in 22%; and overall, 40% developed vascular complications. Late hepatic artery complications occurred more often in living donor recipients transplanted for CCA compared with the living donor control group (P = 0.047). Late portal vein complications occurred more often in both whole organ and living donor recipients transplanted for CCA compared with the control groups (P = 0.01 and P = 0.009). Hepatic venous complications were rare. Patient and graft survival were not different between CCA and control patients. Liver transplantation with neoadjuvant therapy is associated with far higher rates of late arterial and portal venous complications, but these complications do not adversely affect patient and graft survival. Liver Transpl, 2007. © 2007 AASLD.
An efficient co‐rotational formulation for curved triangular shell element
Authors: Li Zhongxue , Vu‐Quoc Loc
Published: April 2007

A 6‐node curved triangular shell element formulation based on a co‐rotational framework is proposed to solve large‐displacement and large‐rotation problems, in which part of the rigid‐body translations and all rigid‐body rotations in the global co‐ordinate system are excluded in calculating the element strain energy. Thus, an element‐independent formulation is achieved. Besides three translational displacement variables, two components of the mid‐surface normal vector at each node are defined as vectorial rotational variables; these two additional variables render all nodal variables additive in an incremental solution procedure. To alleviate the membrane and shear locking phenomena, the membrane strains and the out‐of‐plane shear strains are replaced with assumed strains in calculating the element strain energy. The strategy used in the mixed interpolation of tensorial components approach is employed in defining the assumed strains. The internal force vector and the element tangent stiffness matrix are obtained from calculating directly the first derivative and second derivative of the element strain energy with respect to the nodal variables, respectively. Different from most other existing co‐rotational element formulations, all nodal variables in the present curved triangular shell formulation are commutative in calculating the second derivative of the strain energy; as a result, the element tangent stiffness matrix is symmetric and is updated by using the total values of the nodal variables in an incremental solution procedure. Such update procedure is advantageous in solving dynamic problems. Finally, several elastic plate and shell problems are solved to demonstrate the reliability, efficiency, and convergence of the present formulation. Copyright © 2007 John Wiley & Sons, Ltd.
Topology optimization of dynamics problems with Padé approximants
Authors: Jensen Jakob S.
Published: April 2007

An efficient procedure for topology optimization of dynamics problems is proposed. The method is based on frequency responses represented by Padé approximants and analytical sensitivity analysis derived using the adjoint method. This gives an accurate approximation of the frequency response over wide frequency ranges and a formulation that allows for design sensitivities to be computed at low computational cost also for a large number of design variables. Two examples that deal with optimization of forced vibrations are included. Copyright © 2007 John Wiley & Sons, Ltd.
Conducting polyaniline‐coated nano silica by in situ chemical oxidative grafting polymerization
Authors: Lei Xiping , Su Zhixing
Published: April 2007

Polyaniline (PAni) grafted nano silica were synthesized successfully by in situ polymerization of aniline (An) using ammonium persulphate (APS) as oxidant by three procedures: Firstly, γ‐(2,3‐epoxypropoxy)propyltrimethoxysilane (EPTMS) reacted with nano silica. Secondly, the EPTMS modified nano silica reacted with An as an initiator site introduced onto the silica surface, and finally PAni grafted silica was obtained by in situ chemical oxidative An. The chemical grafting of PAni was confirmed by FTIR and UV–Vis. The percentages of grafting EPTMS and An onto nano silica were 24.5 wt% and 10.3 wt%, respectively, calculated from elemental analysis (EA), while the percentage of grafting PAni was 157.7 wt% as a mass ratio of the grafting PAni and charged nano silica, investigated by TGA. In addition, characteristic agglomerate morphology of PAni was observed in the composite by SEM. The electrical conductivity of the product was 2.6 × 10−6 S cm−1 and it manifested that the resulted product was a typical semiconductor. Copyright © 2007 John Wiley & Sons, Ltd.
Preparation and characterization of poly(acrylic acid)‐iron rich smectite superabsorbent composites
Authors: Seki Yoldaş , Torgürsül Ali , Yurdakoc Kadir
Published: April 2007

A novel poly(acrylic acid)‐iron rich smectite (IRS) superabsorbent composite was synthesized by graft copolymerization reaction of acrylic acid (AA) in the presence of N,N‐methylenebisacrylamide (MBA) as a crosslinker. IRS was used to strengthen the hydrogel products in the polymerization process. Water absorbencies for these superabsorbent composites in water and saline solutions were investigated. IRS caused a reduced equilibrium swelling as low as 8–26%. However, grafted IRS particles resulted in improved gel strength as high as 66% compared to the IRS‐free sample. IRS modified superabsorbent hydrogel composites exhibited higher thermal stability compared to the IRS‐free sample. The pH dependent reversible swelling behavior of hydrogels was also investigated. It is found that the swelling process is pH dependent and reversible for synthesized superabsorbent. Superabsorbent hydrogel composites were characterized by thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). FTIR spectroscopy was confirmed grafting of acrylic chains onto the surface of IRS particles. From the standpoint of these results, these strengthened and thermostabilized hydrogels may be considered as good candidates for a controlled release study and agricultural applications. Copyright © 2007 John Wiley & Sons, Ltd.
Role of BRAF‐V600E in the serrated pathway of colorectal tumourigenesis
Authors: Minoo P , Moyer MP , Jass JR
Published: April 2007

There is increasing evidence for an alternative pathway of sporadic colorectal tumourigenesis that is associated with DNA microsatellite instability (MSI), due to methylation and loss of expression of the mismatch repair gene MLH1. Recent studies have highlighted a serrated pathway of colorectal cancer (CRC) in which serrated polyps with activating mutations in BRAF progress to CRCs with MSI following methylation and silencing of MLH1. The present study provides a novel mechanistic experimental model for these clinical observations. We investigated the role of BRAF activating mutation (BRAF‐V600E) in colorectal tumourigenesis by studying the effects of forced expression of BRAF‐V600E in the ‘normal’ colon epithelial NCM460 cell line and by targeting endogenous BRAF‐V600E in MSI‐High (MSI‐H) colon cancer cell lines. The findings indicate that BRAF mutation in colon epithelial cells contributes to a gain in resistance towards apoptotic stimuli, which is likely to be an important characteristic of pre‐malignant serrated lesions. BRAF‐V600E also plays a role in the development and maintenance of transformed and invasive phenotypes in colon epithelial cells. Our findings also suggest that BRAF mutation potentiates promoter hypermethylation of the MLH1 gene promoter. Together, these results highlight BRAF as a potential target for therapeutic intervention in sporadic MSI‐H colorectal cancers. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
β‐Thalassemia major births after National Screening Program in Taiwan
Authors: Chern Jimmy P.S. , Lin Kai‐Hsin , Lu Meng‐Yao , Lin Dong‐Tsamn , Jou Shiann‐Tarng , Yang Yung‐Li , Chang Hsiu‐Hao , Su Syi , Lin Kuo‐Sin
Published: April 2007

Objective

A National Thalassemia Screening Program was adopted in Taiwan in 1993. This report examined that program's results and impact.

Methods

Patients with β‐thalassemia major born between 1994 and 2003 were recruited through the help of all thalassemia clinics in Taiwan. A structured questionnaire was designed to collect the reasons for affected births.

Results

There were 97 affected births from 1994 to 2003.These births resulted after informed choice (n = 4), screening problems (n = 83), and undetermined causes (n = 10). Approximately 83% (5/6) of affected births in 2003 came from interracial marriages.

Conclusions

This report has identified several areas that might improve the thalassemia‐screening program, including carrier screening in high school rather than in early pregnancy and the involvement of genetic counselors, providing care of new female immigrants. Pediatr Blood Cancer 2008;50:58–61. © 2007 Wiley‐Liss, Inc.
Composite adrenal anaplastic neuroblastoma and virilizing adrenocortical tumor with germline TP53 R248W mutation
Authors: Rossbach Hans‐Christoph , Baschinsky Dmitry , Wynn Tung , Obzut Dana , Sutcliffe Maxine , Tebbi Cameron
Published: April 2007

Composite tumors are extremely rare. Such tumors in adrenal glands are usually of neuroendocrine‐neural type and occur mostly in adults. Their pathogenesis remains elusive. We report a patient with composite neuroblastoma (NB), adrenocortical tumor (ACT), and Li‐Fraumeni syndrome (LFS) with germline TP53 R248W mutation. LFS predisposes to the development of leukemia, sarcomas, adrenocortical and breast carcinomas, brain tumors and, questionably, NB. A unique correlation between a single TP53 mutation (R337H) and ACT has been reported in southern Brazilian children. It remains unclear at this time whether a similar association of NB and R248W in patients with LFS exists. Pediatr Blood Cancer 2008;50:681–683. © 2007 Wiley‐Liss, Inc.
Photopolymerization kinetics of cycloaliphatic epoxide–acrylate hybrid monomer
Authors: He Yong , Xiao Ming , Wu Feipeng , Nie Jun
Published: April 2007

An epoxide–acrylate hybrid monomer was synthesized by the controlled reaction of a cycloaliphatic epoxide and acrylic acid. The photopolymerization kinetics was investigated using a real‐time infrared spectroscopy technique. The influences of photoinitiator concentration, free radical initiator and polymerization atmosphere on the polymerization were studied. The hybrid monomer showed unique photopolymerization kinetics in the photopolymerization process and the final conversions of epoxy groups and acrylate double bonds were improved synchronously. Dynamic mechanical analysis results demonstrated that the hybrid monomer cured film formed a more uniform polymer network than the blend of epoxy acrylate and epoxide. Copyright © 2007 Society of Chemical Industry
Studies on the kinetics and mechanism of the copolymerization of acrylonitrile with styrene in the presence of zinc chloride
Authors: Srivastava N. , Rai J. S. P.
Published: April 2007

Radical copolymerization of acrylonitrile (AN) with styrene (Sty), using x,x′‐azobisisobutyronitrile as initiator, was carried out in the presence of zinc chloride (ZnCl2) dilatometrically at 65/pm 0.1 C for 120min. The rate of polymerization was a direct function of the concentrations of ZnCl2, AN and Sty, and polymerization temperature. The viscosity‐average molecular weight of the copolymer increased with ZnCl2 concentration. The energy of activation in the presence and absence of the complex was evaluated as 82.5 kJ mol−1 and 115.5 kJ mol−1, respectively. The copolymerization of AN with Sty proceeded via the radical‐complex mechanism.
Dielectric relaxation studies of heterogeneously substituted cellulose acetate and its plasticization by dibutyl phthalate
Authors: Doyle Stephen J. , Pethrick Richard A.
Published: April 2007

Dielectric relaxation measurements are reported on plasticized commercial and heterogeneously substituted cellulose acetate. Differences in the observed behaviour are attributed to the retention of a degree of crystallinity and microscopic structure in the original substituted cellulose samples. A comparison of dynamic mechanical and dielectric relaxation data further emphasizes the influence of the nature of the original morphology on the micro dynamics.