bluuebunny/crossref_metadata_2025 huggingface dataset:
Receptor versus Counterion: Capability of N,N′‐Bis(2‐aminobenzyl)‐diazacrowns for Giving Endo‐ and/or Exocyclic Coordination of ZnII
Authors: Vaiana Lea , Platas‐Iglesias Carlos , Esteban‐Gómez David , Avecilla Fernando , de Blas Andrés , Rodríguez‐Blas Teresa
Published: March 2007

The structure of ZnII complexes with receptors L1 and L2[L1 = N,N′‐bis(2‐aminobenzyl)‐1,10‐diaza‐15‐crown‐5 and L2 = N,N′‐bis(2‐aminobenzyl)‐4,13‐diaza‐18‐crown‐6] was studied both in the solid state and in acetonitrile solution. Both receptors form mononuclear ZnII complexes in this solvent, while no evidence for the formation of dinuclear complexes was obtained. This is in contrast with previous investigations that demonstrated the formation of dinuclear complexes of L2 with first‐row transition metals such as NiII, CoII and CuII. Compounds of formula [Zn(L1)](ClO4)2 (1), [Zn(L1)](NO3)2·2CH3CN (2), [Zn(L2)](ClO4)2 (3) and [Zn(L2)(NO3)2] (4) were isolated and structurally characterised by X‐ray diffraction analyses. L1 forms seven‐coordinate ZnII complexes in the presence of both nitrate and perchlorate anions, as a consequence of the good fit between the macrocyclic cavity and the ionic radius of the metal ion. The ZnII ion is deeply buried into the receptor cavity and the anions are forced to remain out of the metal coordination sphere. The cation [Zn(L1)]2+ present in 1 and 2 is one of the very few examples of seven‐coordinate Zn complexes. Receptor L2 provides a very rare example of a macrocyclic receptor allowing endocyclic and exocyclic coordination on the same guest cation, depending on the nature of the anion present. Thus, in 3 the ZnII ion is endocyclically coordinated, placed inside the crown hole coordinated to four donor atoms of the ligand in a distorted tetrahedral environment, whereas in 4, the presence of a strongly coordinating anion such as nitrate results in an exocyclic coordination of ZnII, which is directly bound only to the two primarily amine groups of L2 and two nitrate ligands. Spectrophotometric titrations of [Zn(L2)]2+ with tetrabutylammonium nitrate in acetonitrile solution demonstrate the stepwise formation of 1:1 and 1:2 adducts with this anion in acetonitrile solution. The [Zn(L1)]2+, [Zn(L2)]2+ and [Zn(L2)(NO3)2] systems were characterised by means of DFT calculations (B3LYP model). The calculated geometries show an excellent agreement with the experimental structures obtained from X‐ray diffraction analyses. Calculated binding energies of the macrocyclic ligands to ZnII are also consistent with the experimental data.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Cover Picture: Active Site Protonation of 1‐Azafagomine in Glucosidases Studied by Solid‐State NMR Spectroscopy (Eur. J. Org. Chem. 11/2007)
Authors: Sivertsen Astrid C. , Gasior Magdalena , Bjerring Morten , Hansen Steen U. , Lopez Lopez Oscar , Nielsen Niels C. , Bols Mikael
Published: March 2007

The cover picture shows the glycosidase inhibitor 1‐azafagomine binding to the enzyme β‐glucosidase in the magnetic field of a solid‐state NMR spectrometer. Details are discussed in the article by N. C. Nielsen, M. Bols et al. on p. 1735 ff.
Mixture‐based modeling for space–time data
Authors: Porcu E. , Mateu J.
Published: March 2007

An overview of spatio‐temporal covariance functions built through mixtures is presented in this paper. We highlight the potentiality of mixture modeling for the construction of nonseparable space–time covariances. In particular, we make use of mixed forms (MF), copulas, and completely monotone functions as the basic setup representing powerful instruments to build mixture‐based covariance functions. We re‐analyze, by using a particular model of mixtures, the Indian Ocean wind speed data and compare the results with others previously published in the literature. Copyright © 2007 John Wiley & Sons, Ltd.
Frequency analysis of rectangular plates continuous in one or two directions
Authors: Wu C. I. , Cheung Y. K.
Published: March 2007

The finite strip method is extended to the free vibration of rectangular plates continuous in one or two directions. A subroutine has been written for the computation of beam functions for continuous beams over any number of intermediate rigid supports and with simply supported or clamped end conditions. The standard finite strip method can thus be applied to plates continuous in both directions using the computed beam functions.

The frequencies of 2 × 2 and 3 × 3 continuous panels with many different end conditions have been computed. The computations are also checked against published solutions and the accuracy is shown to be excellent.
Mathematical models for the dynamic analysis of concrete gravity dams
Authors: Rea Dixon , Liaw C‐Y. , Chopra Anil K.
Published: March 2007

The results from field tests on Pine Flat Dam near Fresno, California, are described. The results are then used in the formulation of a three‐dimensional mathematical model of the dam and a two‐dimensional mathematical model of one of the taller monoliths. The significance of these mathematical models in relationship to the behaviour of concrete gravity dams during earthquakes is also discussed.
Automatic masters for eigenvalue economization
Authors: Henshell R. D. , Ong J. H.
Published: March 2007

In dynamic analyses using the finite element method very large matrices are derived. The size of the matrices is usually reduced using an eigenvalue economization method. This paper describes an automatic technique for selecting the optimum variables to be kept as masters using the economization method. Some examples are presented and these lead to an empirical statement about expected accuracy.
Seismic response of long multiple‐span highway bridges
Authors: Tseng W. S. , Penzien J.
Published: March 2007

Non‐linear seismic responses are described for three prototype, long, multiple‐span, reinforced concrete, modern highway bridge structures, namely the 5/14 South Connector Overcrossing and the curved Figueroa Street Under‐crossing as designed by the California Department of Transportation, and a straight version of the Figueroa Street Undercrossing. The analytical seismic responses are discussed and are correlated with the apparent prototype behaviour experienced during the San Fernando, California, earthquake of 9 February 1971. In particular, the causes of collapse of the 5/14 South Connector Overcrossing are identified and examined. Finally, based on parameter studies of the seismic responses of these structures, general conclusions and recommendations related to seismic design methodology are presented.
Comparative seismic analyses of a framed tube with localized and general non‐linearity
Authors: Huckelbridge Arthur A. , Ferencz Robert M.
Published: March 2007

In this paper the seismic response of a 30 storey framed tube is examined. A description is given of an analysis procedure utilizing a linear substructure to represent the building superstructure, achieving considerable economy in computational effort. Localized non‐linearity in the form of transient foundation uplift is included as a response feature. Comparisons of substructured to non‐substructured analyses for the same ground motion are made. Lastly, the effects of more generalized superstructure non‐linearity are examined by comparing the results of such an analysis to those described above.
Seismicity and earthquake hazard in Trinidad and Tobago, West Indies
Authors: Shepherd J. B. , Aspinall W. P.
Published: March 2007

The two‐island Republic of Trinidad and Tobago in the eastern Caribbean has enjoyed increased physical and industrial development in recent years; however, these islands have been subjected to damaging earthquakes during their history and an up‐to‐date risk assessment is needed. We examine two approaches to quantifying this problem: (a) the risk estimated probabilistically using recent instrumental data and (b) the hazard inferred from regional tectonic movements. The probabilistic approach indicates that peak ground accelerations with a probability of exceedance of 10 per cent in 50 years could range from 0–23g in Tobago to 0–36g in North‐West Trinidad. Tectonic considerations suggest that a maximum‐moment earthquake occurring directly under either land mass could generate accelerations as high as 0–6g; the probability of occurrence of such an event is estimated to be about 2 per cent in 50 years for Trinidad and about a tenth this risk for Tobago. This level of hazard would be significant for critical facilities such as LNG plants.
Reliability upgrading of lifeline networks for post‐earthquake serviceability
Authors: Moghtaderi‐Zadeh Masoud , Kiureghian Armen Der
Published: March 2007

Efficient procedures for reliability upgrading of existing lifeline networks for post‐earthquake serviceability are presented. A simple method is developed to determine critical components of the network whose strengthening improves the network reliability for specified serviceability criteria. Measures of effectiveness of strengthening each component are also introduced. Based on critical components and measures of effectiveness, step‐by‐step upgrading procedures are proposed. Both connectivity and minimum‐flow serviceability criteria may be specified. Two upgrading objectives considered are achieving a specified target reliability and reducing the total costs of upgrading plus expected losses due to failure of the lifeline. A hypothetical application to a water‐distribution system in the San Francisco Bay Area illustrates the proposed method.
Modelling hysteretic behaviour of coupled walls for dynamic analysis
Authors: Saatcioglu Murat , Derecho Arnaldo T. , Corley W. G.
Published: March 2007

Modelling techniques for dynamic inelastic response analysis of coupled wall structures are investigated. Emphasis is placed on effects of parameters defining the force‐displacement hysteresis loop. Specifically, effects of axial force‐moment interaction, strength reduction, shear yielding, pinching, reloading and unloading branches of hysteresis loops are considered. Effects of modelling parameters on selected response quantities are investigated and discussed in detail.

A 20‐storey coupled wall structure was selected for dynamic analysis. Ranges of parameters characterizing force‐displacement hysteresis loops were obtained from laboratory tests under slowly reversed static loading. Previously recorded strong motion accelerograms were used as input motions.

Results indicate that wall axial forces and beam strength reduction can have significant effects on response envelopes. Moderate variations in unloading and reloading branches of hysteresis loops and pinching appear to have little effect on dynamic response.
Efficient high‐resolution relaxation schemes for hyperbolic systems of conservation laws
Authors: Kumar Ritesh , Kadalbajoo M. K.
Published: March 2007

In this work, we present a total variation diminishing (TVD) scheme in the zero relaxation limit for nonlinear hyperbolic conservation law using flux limiters within the framework of a relaxation system that converts a nonlinear conservation law into a system of linear convection equations with nonlinear source terms. We construct a numerical flux for space discretization of the obtained relaxation system and modify the definition of the smoothness parameter depending on the direction of the flow so that the scheme obeys the physical property of hyperbolicity. The advantages of the proposed scheme are that it can give second‐order accuracy everywhere without introducing oscillations for 1‐D problems (at least with) smooth initial condition. Also, the proposed scheme is more efficient as it works for any non‐zero constant value of the flux limiter ϕ ϵ [0, 1], where other TVD schemes fail. The resulting scheme is shown to be TVD in the zero relaxation limit for 1‐D scalar equations. Bound for the limiter function is obtained. Numerical results support the theoretical results. Copyright © 2007 John Wiley & Sons, Ltd.
Identification of antigenic targets of paraproteins by expression cloning does not support a causal role of chronic antigenic stimulation in the pathogenesis of multiple myeloma and MGUS
Authors: Preuss Klaus‐Dieter , Held Gerhard , Kubuschok Boris , Hung Chun‐Zhu , Malatsidze Natalia , Wagner Mathias , Pfreundschuh Michael
Published: March 2007

Antigenic targets of monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) paraproteins have been suggested to play an important role as growth stimulators in the pathogenesis of these neoplasms. To identify such targets, we screened cDNA libraries from human testis, lung and breast cancer, bovine and porcine muscle and wheat germ for reactivity with paraproteins in the sera from 115 patients with MGUS and MM. Of >6 × 108 paraprotein–antigen interactions screened, an IgA paraprotein from a female patient bound to sperm‐specific cylicin‐2, and 3 IgG paraproteins bound to tripeptidyl‐peptidase‐II (TPP‐2), insulin‐like growth‐factor binding‐protein‐2 (IGFBP‐2) and porcine kinesin. Specificity was confirmed by reverse Western blots using recombinant antigens. The broad spectrum of auto‐, allo‐ and heteroantigens as targets of human paraproteins in patients without signs of chronic antigenic stimulation renders a causal role of the antigenic stimulus in the pathogenesis of MGUS and MM unlikely. © 2007 Wiley‐Liss, Inc.
Beta2‐microglobulin mutations in microsatellite unstable colorectal tumors
Authors: Kloor Matthias , Michel Sara , Buckowitz Boris , Rüschoff Josef , Büttner Reinhard , Holinski‐Feder Elke , Dippold Wolfgang , Wagner Rudolf , Tariverdian Mirjam , Benner Axel , Schwitalle Yvette , Kuchenbuch Beate , von Knebel Doeberitz Magnus
Published: March 2007

Defects of DNA mismatch repair (MMR) cause the high level microsatellite instability (MSI‐H) phenotype. MSI‐H cancers may develop either sporadically or in the context of the hereditary nonpolyposis colorectal cancer (HNPCC) syndrome that is caused by germline mutations of MMR genes. In colorectal cancer (CRC), MSI‐H is characterized by a dense lymphocytic infiltration, reflecting a high immunogenicity of these cancers. As a consequence of immunoselection, MSI‐H CRCs frequently display a loss of human leukocyte antigen (HLA) class I antigen presentation caused by mutations of the β2‐microglobulin (β2m) gene. To examine the implications of β2m mutations during MSI‐H colorectal tumor development, we analyzed the prevalence of β2m mutations in MSI‐H colorectal adenomas (n = 38) and carcinomas (n = 104) of different stages. Mutations were observed in 6/38 (15.8%) MSI‐H adenomas and 29/104 (27.9%) MSI‐H CRCs. A higher frequency of β2m mutations was observed in MSI‐H CRC patients with germline mutations of MMR genes MLH1 or MSH2 (36.4%) compared with patients without germline mutations (15.4%). The high frequency of β2m mutations in HNPCC‐associated MSI‐H CRCs is in line with the hypothesis that immunoselection may be particularly pronounced in HNPCC patients with inherited predisposition to develop MSI‐H cancers. β2m mutations were positively related to stage in tumors without distant metastases (UICC I‐III), suggesting that loss of β2m expression may promote local progression of colorectal MSI‐H tumors. However, no β2m mutations were observed in metastasized CRCs (UICC stage IV, p = 0.04). These results suggest that functional β2m may be necessary for distant metastasis formation in CRC patients. © 2007 Wiley‐Liss, Inc.
Trends in lung cancer among young European women: The rising epidemic in France and Spain
Authors: Levi Fabio , Bosetti Cristina , Fernandez Esteve , Hill Catherine , Lucchini Franca , Negri Eva , La Vecchia Carlo
Published: March 2007

Lung cancer mortality in young women in the European Union (EU) has steadily increased until the mid 1990s and has levelled off thereafter, but trends have been heterogeneous in various countries. We analyzed therefore age‐standardized trends in lung cancer mortality in young women (20–44) for the 6 major European countries, using joinpoint regression. In the early 1970s the highest lung cancer mortality in young women was in the UK (2.1/100,000). UK rates, however, steadily declined and in 2000–2004 they were the lowest of all 6 major EU countries (1.2/100,000). The second lowest rate in 2000–2002 was in Italy, whose rates remained around 1.1/100,000 between 1970 and 1994, and increased to 1.4 thereafter. In Germany and Poland, lung cancer rates in young women rose from 0.8–1.0/100,000 in the early 1970s to 1.7–1.9 in the mid 1990s and levelled off during the last decade. Major rises over recent years were observed in France (from 0.8/100,000 in 1985–1989 to 2.2 in 2000–2003) and in Spain (from 0.8 in the 1985–1989 to 1.7 in 2000–2004). Thus, France showed both the highest rate observed over the last 3 decades and the largest rise over the last 2 decades. Since recent trends in the young give relevant information to the likely future trends in middle age, the female lung cancer epidemic is likely to expand in southern Europe from the current rates of 5.0/100,000 in Spain and 7.7 in France to approach 20/100,000 within the next 2–3 decades. Urgent interventions for smoking cessation in women are therefore required. © 2007 Wiley‐Liss, Inc.
The role of tumor microenvironment in prostate cancer bone metastasis
Authors: Morrissey Colm , Vessella Robert L.
Published: March 2007

Prostate cancer (PCa) epithelial cells require a number of factors to facilitate their establishment and growth at a distant site of metastasis. Their ability to adapt to their microenvironment, proliferate and recruit an underlying stroma is integral to the survival and growth of the metastasis. PCa predominantly metastasizes to the bone, and bone metastases are the main cause of morbidity. The bone marrow provides a permissive environment for the formation of a metastasis. In some cases, the cells may remain dormant for some time, eventually proliferating in response to an unknown “trigger.” The marrow is rich in progenitor cells that differentiate into numerous cell types, producing new blood vessels, supporting fibroblasts, and an underlying extracellular matrix (ECM) that form the reactive stroma. By secreting a number of cytokines, growth factors and proteases they recruit auxiliary cells required to produce a functional stroma. These components are involved in a reciprocal interaction between the stroma and the PCa cells, allowing for the growth and survival of the tumor. Left unchecked, once a PCa tumor has established itself in the bone marrow it will eventually replace the marrow, interrupting bone homeostasis and typically promoting an osteoblastic response in the bone including osteoclastic events. The abundant deposition of new woven bone results in nerve compression, bone pain and an increase in fractures in patients with PCa bone metastases. This review will examine the tumor microenvironment, its role in facilitating tumor dissemination, growth and the resultant pathologies associated with PCa bone metastasis. J. Cell. Biochem. 101: 873–886, 2007. © 2007 Wiley‐Liss, Inc.
Serum Levels of CA19‐9 in patients with nonmalignant respiratory diseases
Authors: Kodama Takahide , Satoh Hiroaki , Ishikawa Hiroichi , Ohtsuka Morio
Published: March 2007

CA19‐9 is a specific tumor marker in patients with gastrointestinal cancer; however, some patients with respiratory disease can have elevated serum levels of CA19‐9 as well. In this study we evaluated serum CA19‐9 levels of patients with nonmalignant respiratory diseases. We also estimated the prognostic significance of elevated serum levels of CA19‐9 in patients with interstitial lung diseases. The study included 554 patients who had been diagnosed at our hospital during the period of 1984–2005. Serum CA19‐9 levels in these patients were measured with a commercially available kit. Elevated levels (>37 U/mL) of CA19‐9 were observed in 30.7% of patients with lung cancer. Furthermore, 38.9% of patients with idiopathic interstitial pneumonia (IIP), collagen disease‐associated pulmonary fibrosis (CDPF), diffuse panbronchiolitis (DPB), and bronchiectasis had elevated serum CA19‐9 levels. Survival rates were significantly lower in patients with interstitial lung diseases (IIP and CDPF) and elevated serum CA19‐9 levels than in those with levels in the normal range (P=0.0065). Serum CA19‐9 was elevated in some patients with nonmalignant diffuse lung diseases. Therefore, clinicians should pay attention to the evidence that increased serum CA19‐9 levels can be found in nonmalignant respiratory disease patients. In patients with IIP and CDPF, elevated serum CA19‐9 levels may be related to poor prognosis. J. Clin. Lab. Anal. 21:103–106, 2007. © 2007 Wiley‐Liss, Inc.
Hypoxia‐induced apoptosis and tube breakdown are regulated by p38 MAPK but not by caspase cascade in an in vitro capillary model composed of human endothelial cells
Authors: Ohta Toshiro , Eguchi Ryoji , Suzuki Akio , Miyakaze Shinichi , Ayuzawa Rie , Kaji Kazuhiko
Published: March 2007

In order to improve medical treatment of ischemic injury such as myocardial infarction, it is important to elucidate hypoxia‐induced changes to endothelial cells. An in vitro blood vessel model, in which HUVECs are stimulated to form a network of capillary‐like tubes, was used to analyze hypoxia‐induced morphological and biochemical changes. When exposed to hypoxia, the network of capillary tubes broke down into small clusters. This tube breakdown was accompanied by chromatin condensation and cell nuclear fragmentation, morphological markers of apoptosis, and activation of two apoptotic signals, caspase‐3 and p38. We investigated what roles caspase cascade and p38 play in hypoxia‐induced apoptosis and tube breakdown by using zVAD‐fmk and SB203580, specific inhibitors of these two apoptotic signals, respectively. Chromatin condensation and cell nuclear fragmentation and tube breakdown were effectively inhibited by SB203580, but not by zVAD‐fmk. SB203580 caused dephosphorylation of p38, which indicates that p38 was autophosphorylated. Inhibition by zVAD‐fmk caused slight MW increase in p17 and emergence of p19, which indicates that the inhibitor caused partial processing of caspase‐3. Inhibition of p38 suppressed activation of caspase‐3 but not vice versa. In addition, these two inhibitors were shown to differentially inhibit cleavage of so‐called caspase substrates. SB203580 inhibited cleavage of PARP and lamin A/C, while zVAD‐fmk inhibited cleavage of lamin A/C but not that of PARP. Taken together, these results show that p38 is located upstream of caspase cascade and that, although caspase‐3 is activated, a p38‐regulated caspase‐independent pathway is crucial for the execution of hypoxia‐induced apoptosis and tube breakdown. J. Cell. Physiol. 211: 673–681, 2007. © 2007 Wiley‐Liss, Inc.
Knowledge and attitude toward HIV voluntary counseling and testing services among pregnant women attending an antenatal clinic in Sudan
Authors: Mahmoud Mariam M. , Nasr Abubakr M. , Gassmelseed Dar Elgalal A. , Abdalelhafiz Mohamed. A. , Elsheikh Mohamed A. , Adam Ishag
Published: March 2007

Human immunodeficiency virus (HIV) infection and the development of the acquired immunodeficiency syndrome (AIDS) are increasing at an alarming rate especially in the sub‐Saharan region. Pregnant women susceptible to HIV and its transmission to the fetus provide a unique opportunity for implementing preventive strategy against HIV infection of newborn babies. During the period of August–December 2005 a cross‐sectional study was conducted at the Fath‐Elrahman Elbashir antenatal clinic, Khartoum Teaching Hospital, to investigate pregnant women's basic knowledge and attitude toward HIV and mother to child transmission as well as voluntary counseling and testing. Pre‐tested structured questionnaires were given to antenatal attendants by professional counselors. Their basic socio‐demographic and obstetric characteristics were obtained. Respondents' knowledge about HIV and mother to child transmission were tested. In addition, their willingness toward HIV testing was also reported. Out of the 1,005 women investigated, 79% had basic knowledge about HIV. Those who were resident in Khartoum and whose age was ≥26.1 years and their education level was secondary and above were found to be more knowledgeable about HIV. More than half of respondents were aware of mother to child transmission. Older (≥26.1 years), educated, and working mothers were found to be more knowledgeable about mother to child transmission. Willingness to undergo the test was demonstrated in 72.8% of respondents. However, only 30.3% had the test done. Older women, primigravidae, and Muslims have higher acceptance of voluntary counseling and testing. There is a need to extend the voluntary counseling and testing program in all antenatal clinics. In addition, there is a need to increase the level of education and raise health awareness about HIV and mother to child transmission. J. Med. Virol. 79:469–473, 2007. © 2007 Wiley‐Liss, Inc.
Nuclear factor‐κB‐dependent cyclin D1 induction and DNA replication associated with N‐methyl‐D‐aspartate receptor‐mediated apoptosis in rat striatum
Authors: Liang Zhong‐Qin , Wang Xiaoxia , Li Ling‐Yun , Wang Yumei , Chen Ren‐Wu , Chuang De‐Maw , Chase Thomas N. , Qin Zheng‐Hong
Published: March 2007

Cell cycle reentry has been found during apoptosis of postmitotic neurons under certain pathological conditions. To evaluate whether nuclear factor‐κB (NF‐κB) activation promotes cell cycle entry and neuronal apoptosis, we studied the relation among NF‐κB‐mediated cyclin induction, bromodeoxyuridine (BrdU) incorporation, and apoptosis initiation in rat striatal neurons following excitotoxic insult. Intrastriatally injected N‐methyl‐D‐aspartate receptor agonist quinolinic acid (QA, 60 nmol) elicited a rise in cyclin D1 mRNA and protein levels (P < 0.05). QA‐induced NF‐κB activation occurred in striatal neurons and nonneuronal cells and partially colocalized with elevated cyclin D1 immunoreactivity and TUNEL‐positive nuclei. QA triggered DNA replication as evidenced by BrdU incorporation; some striatal BrdU‐positive cells were identified as neurons by colocalization with NeuN. Blockade of NF‐κB nuclear translocation with the recombinant peptide NF‐κB SN50 attenuated the QA‐induced elevation in cyclin D1 and BrdU incorporation. QA‐induced internucleosomal DNA fragmentation was blunted by G1/S‐phase cell cycle inhibitors. These findings suggest that NF‐κB activation stimulates cyclin D1 expression and triggers DNA replication in striatal neurons. Excitotoxin‐induced neuronal apoptosis may thus result from, at least partially, a failed cell cycle attempt. © 2007 Wiley‐Liss, Inc.
Axonal transport of Listeria monocytogenes and nerve‐cell‐induced bacterial killing
Authors: Dons Lone , Jin Yuxuan , Kristensson Krister , Rottenberg Martin E.
Published: March 2007

Listeria monocytogenes (L. monocytogenes) can cause fatal brainstem encephalitis in both sheep and humans. Here we review evidence that the bacteria can be incorporated into axons following a primary cycle of replication in macrophages/dendritic cells after subcutaneous injection in projection areas of peripheral neurons. The molecular mechanisms for the rocketing of L. monocytogenes in the cytosol by asymmetric cometic tails and the utility of this phenomenon for bacterial migration intraaxonally both in retro‐ and in anterograde directions to reach the central nervous system are described. The role of the immune response in the control of L. monocytogenes spread through peripheral neurons is highlighted, and a mechanism by which bacteria may be killed inside infected neurons through a nitric oxide‐dependent pathway is pointed out. © 2007 Wiley‐Liss, Inc.
Optimising dietary energy and amino acid levels in the diets of naked neck broilers for growth, nutrient utilisation and immune response in a hot climate
Authors: Bhanja Subrat K , Mandal Asit B
Published: March 2007

The need for a critical amino acid (AA) profile for growth, immune response and N utilisation of naked neck broilers during summer was studied. Day‐old naked neck chicks (n = 198) from a single hatch were distributed into 24 groups (four dietary regimens (DRs) with six replicates each) having eight birds in each replicate. The first diet was based on crude protein (CP) and metabolisable energy (ME) (13.40 MJ) as per NRC recommendations (DR1). In the second diet, the CP content was reduced through supplementation of synthetic AAs to achieve critical AA contents as suggested by NRC with 13.40 MJ ME (DR2). In the third diet critical AAs were supplemented to achieve their level at 108% of NRC with 12.6 MJ ME (DR3), while in fourth diet critical AA concentration was reduced to 94% (DR4) of NRC with 12.6 MJ ME to match the ratio of ME to AA concentration as that of NRC (1994). Diets were formulated separately for starter (0–3 weeks) and finisher (3‐6 weeks) phases. A metabolism trial was conducted at the third week of age. At 3 and 6 weeks of age eight birds (four of each sex) per treatment were killed to study the growth of immune organs (Bursa of Fabricius, thymus and spleen). Immune response was studied at the fourth week of age. During the starting phase, the birds fed DR1 and DR2 having 13.40 MJ ME kg−1 diet had higher body weight (P < 0.044) gain (P < 0.048) and better feed conversion ratio (FCR) (P < 0.001) as compared to DR3 and DR4 (12.6 MJ ME kg−1 diets). However, better (P < 0.001) CP efficiency (CP intake kg−1 gain) and lower feed cost kg−1 gain (P < 0.001) was recorded in DR4. A similar trend was also observed during the finisher phase. Dietary regimens had no effect on dry matter (DM) metabolisability, N intake or output and N retention. There was no difference in the weight of immune organs (bursa, thymus and spleen) between dietary treatments at either 3 or 6 weeks of age. The cell mediated and humoral immune response was also not different between the NRC and modified NRC levels. Copyright © 2007 Society of Chemical Industry
Enzyme supplements in broiler chicken diets: in vitro and in vivo effects on bacterial growth
Authors: Rosin Erin A , Blank Greg , Slominski Bogdan A , Holley Rick A
Published: March 2007

Increasing the growth performance of broiler chickens by supplementing their diets with exogenous enzymes can also contribute to positive changes in gut health. In this respect the growth of various bacteria normally associated with the gastrointestinal tract of poultry was assessed in vitro using a medium containing arabinoxylan, β‐glucan, guar gum and raffinose and their corresponding enzymes. Overall, enzymes releasing the largest amounts of free sugars yielded the largest increase in bacterial numbers. Accordingly, β‐glucan and raffinose treated with their respective enzymes promoted the largest number of bacterial types, reaching a minimum of 1.0 log10 population within 6 h at 40 °C. A broiler chicken growth trial was also conducted using wheat‐, barley‐ and corn‐based diets with and without enzyme and probiotic addition. Escherichia coli, coliforms, enterococci and aerobic and anaerobic sporeformers were monitored for growth in both the caecum and ileum. Enzyme supplementation reduced E. coli levels in the caecum of broilers fed wheat‐ or corn‐based diets. A further reduction in E. coli numbers was observed in broilers fed the same diets supplemented with a combination of enzyme and probiotic. Enzyme supplementation had much less of an effect on microbial populations in the ileum. Inclusion of probiotics reduced E. coli levels in the caecum and ileum but only in broilers fed wheat‐ and corn‐based diets. Anaerobic spore levels in the ileum increased in all diets containing probiotic. Overall, inclusion of enzymes or probiotics exhibited mixed effects on gut bacteria, depending on the nature of the carbohydrate source and enzyme. Copyright © 2007 Society of Chemical Industry
Acceptability, storage stability and costing of α‐amylase‐treated maize–beans–groundnuts–bambaranuts complementary blend
Authors: Owino Victor O , Sinkala Moses , Amadi Beatrice , Tomkins Andrew M , Filteau Suzanne M
Published: March 2007

The effects of α‐amylase treatment on physical properties, acceptability to mothers, and cost of roasted and extruded maize–beans–groundnuts–bambaranuts complementary porridge recipes were assessed prior to their industrial production. Storage stability of the extruded α‐amylase‐treated fortified blend was assessed at 2 weeks and 6 months by sensory evaluation, peroxide value, water activity and microbiological load. The use of α‐amylase at 0.04% w/w enhanced porridge acceptability and resulted in 88% and 122% increase in flour concentration for roasted and extrusion‐cooked porridge flour, respectively, while maintaining porridge viscosity at 1000‐fold lower than that of traditionally used porridges. The extrusion cooked blend was stable for 6 months. α‐Amylase application increased the unit cost of the developed blend by only 1.4%. The total cost was less than US $ 2 kg−1, half the minimum price of commercially available complementary foods. Further work on marketing and the efficacy of this inexpensive food on growth of infants is warranted. Copyright © 2007 Society of Chemical Industry
Effect of Cd on the growth, dry matter accumulation and grain yield of different rice cultivars
Authors: Liu Jianguo , Cai Guoliang , Qian Min , Wang Deke , Xu Jiakuan , Yang Jianchang , Zhu Qingsen
Published: March 2007

Pot soil experiments showed that there were great variations among six rice cultivars in their tolerance to soil Cd stress, with respect to tillering, plant height, leaf area, dry matter accumulation and grain yield. Some cultivars were highly tolerant of Cd and showed little toxicity under high levels of soil Cd stress (100 mg kg−1), while others were much more sensitive. Roots were not necessarily more sensitive than above‐ground parts, but the diversities among rice cultivars with regard to the relative changes in dry matter accumulation under soil Cd stress were greater in roots than those observed in straw and grain. The toxicity effects of Cd on rice growth and development lessened as plants grew and matured, indicating that rice plants show adaptation and growth compensation in response to soil Cd stress during prolonged exposure. The relative change in the number of grains per panicle showed a strong positive correlation with relative change in grain yield and, of the four grain yield components measured (panicles per pot; grains per panicle; filled grain percentage; weight per grain), it appeared to be the one most influenced by Cd stress. Thus the reduction of grains per panicle is the main cause of grain yield loss under soil Cd stress. Copyright © 2007 Society of Chemical Industry
Phytonutrients affecting hydrophilic and lipophilic antioxidant activities in fruits, vegetables and legumes
Authors: Cho Yoon‐Suk , Yeum Kyung‐Jin , Chen Chung‐Yen , Beretta Giangiacomo , Tang Guangwen , Krinsky Norman I , Yoon Sun , Lee‐Kim Yang Cha , Blumberg Jeffrey B , Russell Robert M
Published: March 2007

The antioxidant activities of fruits (n = 21), vegetables (n = 67) and legumes (n = 7) commonly consumed in Korea were determined by both the lipophilic antioxidant performance assay (LAP) and the hydrophilic oxygen radical absorbance capacity assay (ORAC). The LAP assay used the lipophilic radical initiator MeO‐AMVN [2,2′‐azobis(4‐methoxy‐2,4‐dimethylvaleronitrile)] and the lipophilic probe BODIPY 581/591 [4,4‐difluoro‐5‐(4‐phenyl‐1,3‐butadienyl)‐4‐bora‐3a, 4a‐diaza‐s‐indacene‐3‐undecanoic acid]. The ORAC assay used the hydrophilic radical initiator AAPH [2,2′‐azobis(2‐amidinopropane) dihydrochloride] and the hydrophilic probe fluorescein. In addition, the lipid‐soluble phytonutrients, carotenoids and tocopherols were determined by a reverse‐phase HPLC system using a C30 column with a UV detector. The water‐soluble phytonutrient, ascorbic acid, was analyzed using an HPLC system with an electrochemical detector. Total phenols were determined by UV spectrophotometry. Tocopherols (r = 0.774, p < 0.0001) and carotenoids (r = 0.569, p < 0.0001) were significantly correlated with LAP in total samples (n = 95). ORAC was significantly correlated with total phenols (r = 0.893, p < 0.0001), but not with ascorbic acid (r = 0.009, p = 0.929) in total samples (n = 95). These data indicate that carotenoids and tocopherols and total phenols are the major contributors to the lipophilic and hydrophilic antioxidant capacities, respectively. Therefore, the contribution of both the hydrophilic and lipophilic components of fruits and vegetables should be considered when determining the actual ‘total’ antioxidant activity of fruits and vegetables. Copyright © 2007 Society of Chemical Industry
Comparative behaviour of cellulosic and starchy plant materials during osmotic dehydration
Authors: Tortoe Charles , Orchard John , Beezer Anthony
Published: March 2007

Osmotic dehydration studies on two cellulosic plant materials—Golden Delicious and Cox apple—and two starchy plant materials—banana and potato—showed that the amount and rate of water loss occurred in the following descending order: Golden Delicious > Cox > potato > banana. Temperature, concentration and immersion time of samples in the osmotic solution played a significant effect on amount and rate of water loss in all commodities in a descending order as follows: 55 > 40 > 32.2 °C; 0.70 > 0.60 > 0.50 > 0.40 g kg−1; and 30 > 60 > 90 > 120 min, respectively. A corresponding uptake of solids from the osmotic solution occurred, the rate been greatest over the first 30 min, before declining significantly thereafter. The diffusion coefficients for water loss (Deff, w) measured by the method of slopes on the water loss rate curves conducted at 32.2, 40 and 55 °C for 0.40, 0.50, 0.60 and 0.70 g kg−1 sucrose concentration solutions were higher for cellulosic plant materials than starchy plant materials. Significant variations occurred in efficiency index (WL/SG) between cellulosic and starchy plant materials. Copyright © 2007 Society of Chemical Industry
Pickling brine treatment for possible recycling using high‐pressure homogenization
Authors: Martínez‐García Oscar , Mújica‐Paz Hugo , Valdez‐Fragoso Aurora , Welti‐Chanes Jorge , Ortega‐Rivas Enrique
Published: March 2007

Pickling is a preservation method of vegetables by brine immersion. Residual pickling solutions cannot be reused owing to high yeast content and the presence of polygalacturonase, which may produce vegetable softening. It has been reported that high‐pressure homogenization can reduce enzyme activity and microbial population in liquid foods. An investigation was aimed at studying the effect of high‐pressure homogenization cycles on polygalacturonase activity and yeast survival of residual pickling solutions, from processing of six vegetables. Each pickling solution was pumped through a homogenizing valve at 69 MPa pressure and was recirculated up to 15 times. Yeast counts and polygalacturonase activity were determined in treated solutions after being subjected to 1, 2, 5, 10, and 15 pressure cycles. Untreated and thermally treated solutions were used for comparison. Up to 4 log reductions in yeast inactivation was observed after five high‐pressure cycles treatments, contrasted with only 2 log reductions in thermal treatment. No clear relationship between enzyme inactivation and the number of high pressure cycles, or a thermal parallel effect, were observed. Copyright © 2007 Society of Chemical Industry
The relationship between oxidation stability and antioxidant depletion in turbine oils formulated with Groups II, III and IV base stocks
Authors: Gatto Vincent J. , Moehle William E. , Cobb Tyler W. , Schneller Emily R.
Published: March 2007

Using simple turbine oil formulations, we studied the effects of different antioxidant systems on oxidation behaviour. Fourier transform infrared was used as a sensitive probe to monitor the depletion of different antioxidant types present in turbine oils based on Group II, III and IV base stocks. It was found that the depletion of alkylated diphenylamine antioxidants from turbine oil systems is generally slower when hindered phenolics are present in the formulation. Furthermore, the type of hindered phenolic used in the formulation is critical for preserving this amine activity, with the bis‐phenolic 4,4‐methylenebis(2,6‐di‐tert‐butylphenol) showing superior performance over a phenolic ester of approximately the same molecular weight. This effect was explained by the higher hindered phenolic activity of the bis‐phenolic relative to the phenolic ester. The ability of the bis‐phenolic to preserve or protect the amine antioxidant, combined with its higher hindered phenolic activity, was shown to improve the oxidation resistance of turbine oils. The results also showed a surprisingly high oxidation stability for turbine oils formulated with Group III base stock, with the oxidation resistance of the Group III systems exceeding that of the equivalent Group II and Group IV systems. Copyright © 2007 John Wiley & Sons, Ltd.
Kinetic modeling of proteins adsorption with a methodology of error analysis
Authors: Tavares Câmara Leôncio Diógenes , Costapinto Santana Cesar , da Silva Neto Antônio José
Published: March 2007

The estimation of adsorption parameters for chromatographic systems is a very important step for column characterization used in the design of continuous separation equipments. The turbulent hydrodynamics aspect of batch procedures makes the kinetic modeling an interesting tool for the process modeling used for the determination of the main parameters that will be considered in the equipment design. The implemented irreversible kinetic model, which depends on both solute and site concentrations, was found to be very effective in the experimental correlation of two different enzyme adsorption systems: adsorption of Inulinases and β‐Galactosidase using two different adsorbents, the CM‐Sepharose CL‐6B and Accell plus QMA, respectively. The implementation of an error analysis methodology associated with an inverse problem approach was successful in determining the kinetic parameters with high accuracy. The simulations indicated a decrease in the kinetic constants with an increase in the solute concentration, which can be related to the increase in the competition by sites of adsorption.
Synthesis and chromatographic properties of a chiral stationary phase derived from bovine serum albumin immobilized on magnesia‐zirconia using phosphonate spacers
Authors: Li Ting , Yu Qiong‐Wei , Lin Bo , Feng Yu‐Qi
Published: March 2007

A novel bovine serum albumin (BSA)‐modified magnesia‐zirconia stationary phase was prepared using the sodium salt of cis‐(3‐methyloxiranyl)phosphonic acid (fosfomycin) as spacer and glutaraldehyde as coupler. Baseline separation of six derivatized amino acids (DNB‐Leu, Dansyl‐Val, etc.) was achieved on this column using ammonium acetate buffer‐isopropanol mobile phase at a flow rate of 1.0 mL/min. The effects of mobile phase composition, eluent pH value, column temperature, and flow rate on the retention and separation of chiral compounds were also investigated. The BSA chiral stationary phase (BSA‐CSP) was relatively stable under experimental conditions. The coupling reaction in this method was mild, reliable, and reproducible; thus it was also suitable for the immobilization of various biopolymers with amino groups in the preparation of chromatography stationary phases.
Determination of aqueous inclusion complexation constants and stoichiometry of alkyl(methyl)‐methylimidazolium‐based ionic liquid cations and neutral cyclodextrins by affinity capillary electrophoresis
Authors: François Yannis , Varenne Anne , Sirieix‐Plenet Juliette , Gareil Pierre
Published: March 2007

Affinity CE (ACE) method was developed to characterize the complex formation between seven alkyl(methyl)methylimidazolium‐based ionic liquid (IL) cations and eight neutral cyclodextrins (CD). The effective mobility data of the IL cations were processed according to classical nonlinear and linear treatments to obtain the complex stoichiometry and formation constant K. The majority of systems followed a 1:1 complexation stoichiometry model but in four cases a 1:2 stoichiometry was better satisfied. The K values obtained for each IL were compared to elucidate the main influences of IL and CD nature. The availability of these data should lend support to various application areas, including the screening and tailoring of new interactions in the solution for CE.
Identification of unknown compounds on the basis of retention index data in comprehensive two‐dimensional gas chromatography
Authors: Pang Tao , Zhu Shukui , Lu Xin , Xu Guowang
Published: March 2007

The identification of unknown compounds in complex samples is very difficult. Comprehensive two‐dimensional gas chromatography (GC×GC) provides very good resolution and improved identification reliability. Mass spectrometry is a powerful identification tool and retention index data are another good approach to this end. In this study, a second‐order polynomial was used to calculate retention index data based on n‐alkanes beyond the region of the ‘isovolatile’ curve in GC×GC, and the results in the 2nd dimension were validated by using the same stationary phase column in one‐dimensional GC. To test the usefulness of the method, volatile compounds in a tobacco leaf extract fraction were analyzed using GC×GC, and 60 compounds were identified on the basis of their retention indices.
Psychological issues in the diabetes clinic
Authors: Fosbury J. , Moore S. , Kidd J. , Sonksen P.H. , Amiel S.
Published: March 2007

Psychological difficulties and their effect on diabetes management and diabetes control continue to be debated, whilst the need for psychological treatment is ignored. St Thomas' and Guy's Hospitals offer structured psychological support for their poorly controlled patients using Cognitive Analytic Therapy (CAT). Brief details of CAT are given and the change which occurs in the therapy is outlined in a letter written by a patient at the end of treatment. If we are to maximise diabetes services and minimise disability, psychological treatment needs to be made available to our patients.
Telemedicine in the treatment of diabetic pregnancy
Authors: Fallucca F. , DiBiase N. , Sabbatini A. , Borrello E. , Sciullo E. , Napoli A.
Published: March 2007

Good diabetic patient control requires that treatment be continuously adapted to the patient's behaviour and the control achieved, in order to get the glucose level within a predetermined target range. Several approaches have been documented. Self‐monitoring of blood glucose (SMBG) has become a major element in the care of individuals with diabetes mellitus. In managing the pregnant diabetic patient it must be considered that two patients are being treated: the mother and the fetus. It appears that the strict maintenance of euglycaemia before conception and during the prenatal period may favourably influence perinatal mortality and morbidity. Assuming that easy access to diabetes care providers would allow patients to make appropriate adjustments to their management and thus improve their metabolic control, a controlled trial comparing customary management with continuous diabetes care providing access to patients' self‐monitored glucose data, was undertaken in diabetic pregnancy. In the study, two groups were compared. The Dianet group (7 diabetic pregnant women) used a Diva System: they stored their data in blood glucose meters (ROMEO) with memory to store and transmit data when inserted into JULIET, and this data was directly carried through a telephone modem (JULIET + BOXTEL) to our service every week, and they came to the clinic every two weeks. The control group (10 pregnant diabetic women) recorded their data in a diary and came to the diabetes clinic every week. The use of the telphone modem (DIANET system) stimulated both the patient and the diabetes specialist to keep closer control of blood glucose levels. This might be especially useful in the treatment of diabetes in pregnancy because the patients are usually highly motivated to achieve better metabolic control, as was shown by (a) faster optimisation of blood glucose profiles, (b) better pre‐breakfast and pre‐lunch blood glucose concentration, (c) fewer hypoglycaemic episodes, in the DIANET versus the control group.