bluuebunny/crossref_metadata_2025 huggingface dataset:
DNA adducts and mutagenic specificity of the ubiquitous environmental pollutant 3‐nitrobenzanthrone in Muta Mouse
Authors: Arlt Volker M. , Zhan Li , Schmeiser Heinz H. , Honma Masamitsu , Hayashi Makoto , Phillips David H. , Suzuki Takayoshi
Published: March 2004

3‐nitrobenzanthrone (3‐NBA) is an extremely potent mutagen in the Salmonella reversion assay and a suspected human carcinogen identified in diesel exhaust and in ambient airborne particulate matter. To evaluate the in vivo mutagenicity of 3‐NBA, we analyzed the mutant frequency (MF) in the cII gene of various organs (lung, liver, kidney, bladder, colon, spleen, and testis) in lambda/lacZ transgenic mice (Muta Mouse) after intraperitoneal treatment with 3‐NBA (25 mg/kg body weight injected once a week for 4 weeks). Increases in MF were found in colon, liver, and bladder, with 7.0‐, 4.8‐, and 4.1‐fold increases above the control value, respectively, whereas no increase in MF was found in lung, kidney, spleen, and testis. Simultaneously, induction of micronuclei in peripheral blood reticulocytes was observed. The sequence alterations in the cII gene recovered from 41 liver mutants from 3‐NBA‐treated mice were compared with 32 spontaneous mutants from untreated mice. Base substitution mutations predominated for both the 3‐NBA‐treated (80%) and the untreated (81%) groups. However, the proportion of G:C→T:A transversions in the mutants from 3‐NBA‐treated mice was higher (49% vs. 6%) and the proportion of G:C→A:T transitions was lower than those from untreated mice (10% vs. 66%). The increase in MF in the liver was associated with strong DNA binding by 3‐NBA, whereas in lung, in which there was no increase in MF, a low level of DNA binding was observed (268.0–282.7 vs. 8.8–15.9 adducts per 108 nucleotides). DNA adduct patterns with multiple adduct spots, qualitatively similar to those formed in vitro after activation of 3‐NBA with nitroreductases and in vivo in rats, were observed in all tissues examined. Using high‐pressure liquid cochromatographic analysis, we confirmed that all major 3‐NBA‐DNA adducts produced in vivo in mice are derived from reductive metabolites bound to purine bases (70–80% with deoxyguanosine and 20–30% with deoxyadenosine in liver). These results suggest that G:C→T:A transversions induced by 3‐NBA are caused by misreplication of adducted guanine residues through incorporation of adenine opposite the adduct (A‐rule). Environ. Mol. Mutagen. 43:186–195, 2004. © 2004 Wiley‐Liss, Inc.
Nitrogen oxides emissions reduction technologies in the petrochemical and refining industries
Authors: Baukal Charles E. , Hayes Robert , Grant Mike , Singh Prem , Foote Darin
Published: March 2004

In the petrochemical and refining industries, increasingly stringent regulatory requirements have prompted the development and use of new technologies to minimize nitrogen oxides (NOx) emissions from fired process heaters. Stricter regulations and an increasingly competitive market present significant challenges for petrochemical and refining plants in meeting NOx emissions regulations. The capability of a chosen technology to meet the desired NOx emissions requirements is fundamental to the selection process. Additional factors to consider when evaluating these new technologies include capital and operating costs, downtime, increased complexity of operation and maintenance, safety, and the effects on process heater variables.

This paper considers the problem of economically meeting stricter emissions regulations, presents a general discussion of potential options to meet those requirements, compares the advantages and disadvantages of each with respect to the previously mentioned factors, and presents a case study showing the implementation of a new low NOx burner design which proved much more cost effective and retrofittable than the implementation of a catalytic posttreatment control strategy in a refinery. © 2004 American Institute of Chemical Engineers Environ Prog, 23: 19–28, 2004
Evaluation of industrial biotrickling filter at the flexographic printing facility
Authors: Popov Vladimir O. , Bezborodov Alexey M. , Cavanagh Mary , Cross Phillip
Published: March 2004

While biofiltration and bioscrubbing have already established themselves as standard methods of volatile organic compound (VOC) and odor control, trickling bed biofilter applications are mainly confined to laboratory studies, with only a few installed systems reported in industrial operation. An example of successful industrial biotrickling filter application, controlling highly variable loads of water soluble VOCs at a flexographic printing facility, is presented. The biotrickling filter operates at 14 s contact time and removes on average 7 kg of mixed water‐soluble solvents per hour (280 g per m3 of carrier per hour). The plant is fully compliant with the EC Council Directive 1999/13/EC on the limitation of emissions of VOCs. The operating costs of a biotrickling filter are discussed. © 2004 American Institute of Chemical Engineers Environ Prog, 23: 39–44, 2004
A model for estimating process emissions from gas sweep operations in batch and continuous chemical operations
Authors: Hatfield J. Allen
Published: March 2004

A nitrogen gas sweep is commonly applied to the headspace of a vessel to provide an inert atmosphere. A positive pressure of nitrogen also helps to prevent moisture from entering the vessel and having an adverse impact on the process chemistry. In other processing situations air may sweep through the vessel headspace and leave through the process vent. Evaporation of the volatile solvent takes place within the vessel as contact is made between the fresh supply of nitrogen or air and the liquid contents. © 2004 American Institute of Chemical Engineers Environ Prog, 23: 45–51, 2004
Optimal control of material concentration using Fourier series
Authors: Fujii Hiroyuki , Kawahara Mutsuto
Published: March 2004

This paper presents an optimal control of the material concentration using Fourier series and finite element method. It is assumed that the optimal control value can be expanded into a Fourier series. The Fourier coefficient is identified to minimize the performance function and the optimal control value is determined. The Sakawa–Shindo algorithm is used for the minimization algorithm. The advection–diffusion equation and shallow water equation are used for the analysis of material concentration and water flow. The Crank–Nicolson scheme and finite element method using bubble function element with stabilized control parameter are employed as temporal and special discretization. Copyright © 2004 John Wiley & Sons, Ltd.
A parallel cell‐based DSMC method on unstructured adaptive meshes
Authors: Kim Min Gyu , Kim Hyoung Soon , Kwon Oh Joon
Published: March 2004

A parallel DSMC method based on a cell‐based data structure is developed for the efficient simulation of rarefied gas flows on PC‐clusters. Parallel computation is made by decomposing the computational domain into several subdomains. Dynamic load balancing between processors is achieved based on the number of simulation particles and the number of cells allocated in each subdomain. Adjustment of cell size is also made through mesh adaptation for the improvement of solution accuracy and the efficient usage of meshes. Applications were made for a two‐dimensional supersonic leading‐edge flow, the axi‐symmetric Rothe's nozzle, and the open hollow cylinder flare flow for validation. It was found that the present method is an efficient tool for the simulation of rarefied gas flows on PC‐based parallel machines. Copyright © 2004 John Wiley & Sons, Ltd.
Neuropathological consequences of delivering an adenoviral vector in the rat brain
Authors: McMenamin M. Mary , Lantos Tibor , Carter Emma E. , Hamilton Louise , Charlton Harry M. , Gonzalez S. Charlotte , Wood Matthew J. A.
Published: March 2004

Background

Adenoviruses have many advantages as vehicles for gene delivery to the central nervous system (CNS) and retrograde transport of vectors to axonally linked sites has been postulated as a method for targeting neurons in remote brain regions. To investigate optimisation of this we injected different doses of vector and have documented the neuropathological side effects.

Methods

Increasing doses of a first‐generation adenoviral vector, expressing the lacZ gene, were inoculated in the rat striatum and β‐galactosidase expression was examined at the primary and secondary sites. Subsequently, at the highest dose of vector, transgene expression, the inflammatory response, tyrosine hydroxylase (TH) expression and the rotational behaviour of animals were studied over time.

Results

When a high dose of an adenoviral vector was delivered to the rat striatum, high levels of transgene expression were seen at 5 days in the injection site and in the substantia nigra. Smaller doses gave lower levels of expression with little expression detectable in the substantia nigra. At later time points, with the high dose, a marked reduction in transgene expression was detected and was accompanied by cytopathic damage, a strong inflammatory response and animal weight loss. This was associated with depletion in TH levels and abnormal motor behaviour in animals.

Conclusions

Neuropathological damage in the dopaminergic system, caused by high doses of adenoviral vectors, has not previously been documented. To minimise damage and prolong transgene expression, it is important that the dose of vectors to be delivered is carefully optimised. Copyright © 2004 John Wiley & Sons, Ltd.
Hydrodynamics‐based transfection of the liver: entrance into hepatocytes of DNA that causes expression takes place very early after injection
Authors: Andrianaivo Fanjam , Lecocq Michèle , Wattiaux‐De Coninck Simone , Wattiaux Robert , Jadot Michel
Published: March 2004

Background

The mechanism of gene transfer into hepatocytes by the hydrodynamics‐based transfection procedure is not clearly understood. It has been shown that, after a hydrodynamic injection, a large proportion of plasmid DNA remains intact in the liver where it is bound to plasma membrane and suggested that this DNA could be responsible for the efficiency of the transfection.

Methods

We have investigated the problem by giving mice a hydrodynamic injection of isotonic NaCl, followed at different time intervals by a conventional injection of DNA, cold or labelled with 35S, with cDNA of luciferase as a reporter gene. Then, we determined the consequences of that dual injection on luciferase expression and on DNA uptake by the liver and its intracellular fate. By such experiments, it is possible to establish the time dependency of the induction of liver changes caused by a hydrodynamic injection on the one hand and the expression and DNA uptake and fate on the other. Moreover, some experiments have been performed on primary cultures of hepatocytes isolated after a hydrodynamic injection of DNA.

Results

When DNA is given to mice by a conventional injection a few seconds after an hydrodynamic injection of isotonic NaCl, luciferase expression in the liver is considerably lower than that observed after a single hydrodynamic injection of the plasmid. On the other hand, as assessed by the rate of DNA degradation and by centrifugation results obtained after injection of 35S‐DNA, the uptake and the intracellular fate of the bulk of DNA are similar whether DNA is administered by a single hydrodynamic injection or by a conventional injection given up to at least 2 h after a hydrodynamic injection of isotonic NaCl. Hepatocytes isolated a few minutes after a hydrodynamic injection exhibit a maximal expression that does not depend on the large amount of DNA that remains bound to the plasma membrane for a relatively long time.

Conclusions

Our results show that the efficiency of hydrodynamics‐based transfection depends on a process that takes place very quickly after injection and is not linked to a delay of DNA degradation and the persistence of a large proportion of DNA bound to hepatocytes of the plasma membrane, strongly suggesting that expression after a hydrodynamic injection is caused by a small proportion of DNA molecules that rapidly enter the cytosol probably by plasma membrane pores generated by the hydrodynamic pressure. Copyright © 2004 John Wiley & Sons, Ltd.
Insights into the mechanism of magnetofection using PEI‐based magnetofectins for gene transfer
Authors: Huth Stephanie , Lausier James , Gersting Soeren W. , Rudolph Carsten , Plank Christian , Welsch Ulrich , Rosenecker Joseph
Published: March 2004

Background

Gene delivery by the use of magnetic forces, so‐called magnetofection, has been shown to enhance transfection efficiency of viral and non‐viral systems up to several‐hundred‐fold. For this purpose gene carriers, such as polyethylenimine (PEI), are associated with superparamagnetic nanoparticles and complexed with plasmid DNA. Gene delivery is targeted by the application of a magnetic field.

Methods

To investigate the underlying mechanism, we studied the impact of the applied magnetic field on the transfection process of PEI‐coated superparamagnetic iron oxide gene vectors (magnetofectins) using various cell lines. In particular, we addressed the question whether accelerated sedimentation of magnetofectins is the driving force or if the magnetic field itself directly influences the endocytic processing of the magnetofectins. The cellular uptake mechanism of magnetofectins was studied by electron microscopy and transfection experiments in the presence of various inhibitors that operate at different steps of endocytosis.

Results

In this study we could show that cellular uptake of magnetofectins proceeds obviously by endocytosis. Cellular uptake of magnetofectins behaves almost analogously as compared with PEI polyplexes. Besides unspecific endocytosis, apparently clathrin‐dependent as well as caveolae‐mediated endocytic uptake is involved.

Conclusions

The magnetic field itself does not alter the uptake mechanism of magnetofectins. Obviously, the magnetic forces lead to an accelerated sedimentation of magnetofectins on the cell surface and do not directly affect the endocytic uptake mechanism. So further improvement of magnetic field application could lead to efficient targeting of gene expression into the desired organ and tissuein vivo. Copyright © 2004 John Wiley & Sons, Ltd.
An efficient targeted radiotherapy/gene therapy strategy utilising human telomerase promoters and radioastatine and harnessing radiation‐mediated bystander effects
Authors: Boyd Marie , Mairs Robert J. , Keith W. Nicol , Ross Susan C. , Welsh Philip , Akabani Gamal , Owens Jonathan , Vaidyanathan Ganesan , Carruthers Ross , Dorrens Jennifer , Zalutsky Michael R.
Published: March 2004

Background

Targeted radiotherapy achieves malignant cell‐specific concentration of radiation dosage by tumour‐affinic molecules conjugated to radioactive atoms. Combining gene therapy with targeted radiotherapy is attractive because the associated cross‐fire irradiation of the latter induces biological bystander effects upon neighbouring cells overcoming low gene transfer efficiency.

Methods

We sought to maximise the tumour specificity and efficacy of noradrenaline transporter (NAT) gene transfer combined with treatment using the radiopharmaceutical meta‐[131I]iodobenzylguanidine ([131I]MIBG). Cell‐kill was achieved by treatment with the β‐decay particle emitter [131I]MIBG or the α‐particle emitter [211At]MABG. We utilised our novel transfected mosaic spheroid model (TMS) to determine whether this treatment strategy could result in sterilisation of spheroids containing only a small proportion of NAT‐expressing cells.

Results

The concentrations of [131I]MIBG and [211At]MABG required to reduce to 0.1% the survival of clonogens derived from the TMS composed of 100% of NAT gene‐transfected cells were 1.5 and 0.004 MBq/ml (RSV promoter), 8.5 and 0.0075 MBq/ml (hTR promoter), and 9.0 and 0.008 MBq/ml (hTERT promoter), respectively. The concentrations of radiopharmaceutical required to reduce to 0.1% the survival of clonogens derived from 5% RSV/NAT and 5% hTERT/NAT TMS were 14 and 23 MBq/ml, respectively, for treatment with [131I]MIBG and 0.018 and 0.028 MBq/ml, respectively, for treatment with [211At]MABG.

Conclusions

These results indicate that the telomerase promoters have the capacity to drive the expression of the NAT. The potency of [211At]MABG is approximately three orders of magnitude greater than that of [131I]MIBG. Spheroids composed of only 5% of cells expressing NAT under the control of the RSV or hTERT promoter were sterilised by radiopharmaceutical treatment. This observation is indicative of bystander cell‐kill. Copyright © 2004 John Wiley & Sons, Ltd.
Gene therapy for lysosomal storage diseases: the lessons and promise of animal models
Authors: Ellinwood N. Matthew , Vite Charles H. , Haskins Mark E.
Published: March 2004

There are more than 40 different forms of inherited lysosomal storage diseases (LSDs) known to occur in humans and the aggregate incidence has been estimated to approach 1 in 7000 live births. Most LSDs are associated with high morbidity and mortality and represent a significant burden on patients, their families, and health care providers. Except for symptomatic therapies, many LSDs remain untreatable, and gene therapy is among the only viable treatment options potentially available. Therapies for some LSDs do exist, or are under evaluation, including heterologous bone marrow transplantation (BMT), enzyme replacement therapy (ERT), and substrate reduction therapy (SRT), but these treatment options are associated with significant concerns, including high morbidity and mortality (BMT), limited positive outcomes (BMT), incomplete response to therapy (BMT, ERT, and SRT), life‐long therapy (ERT, SRT), and cost (BMT, ERT, SRT). Gene therapy represents a potential alternative therapy, albeit a therapy with its own attendant concerns. Animal models of LSDs play a critical role in evaluating the efficacy and safety of therapy for many of these conditions. Naturally occurring animal homologs of LSDs have been described in the mouse, rat, dog, cat, guinea pig, emu, quail, goat, cattle, sheep, and pig. In this review we discuss those animal models that have been used in gene therapy experiments and those with promise for future evaluations. Copyright © 2004 John Wiley & Sons, Ltd.
Can the life span of human marrow stromal cells be prolonged by bmi‐1, E6, E7, and/or telomerase without affecting cardiomyogenic differentiation?
Authors: Takeda Yukiji , Mori Taisuke , Imabayashi Hideaki , Kiyono Tohru , Gojo Satoshi , Miyoshi Shunichirou , Hida Naoko , Ita Makoto , Segawa Kaoru , Ogawa Satoshi , Sakamoto Michiie , Nakamura Shinobu , Umezawa Akihiro
Published: March 2004

Background

Cell transplantation has recently been challenged to improve cardiac function of severe heart failure. Human mesenchymal stem cells (hMSCs) are multipotent cells that can be isolated from adult marrow stroma, but because of their limited life span, it is difficult to study them further. To overcome this problem, we attempted to prolong the life span of hMSCs and investigate whether the hMSCs modified with cell‐cycle‐associated genes can differentiate into cardiomyocytes in vitro.

Methods

We attempted to prolong the life span of hMSCs by infecting retrovirus encoding bmi‐1, human papillomavirus E6 and E7, and/or human telomerase reverse transcriptase genes. To determine whether the hMSCs with an extended life span could differentiate into cardiomyocytes, 5‐azacytidine‐treated hMSCs were co‐cultured with fetal cardiomyocytes in vitro.

Result

The established hMSCs proliferated over 150 population doublings. On day 3 of co‐cultivation, the hMSCs became elongated, like myotubes, began spontaneously beating, and acquired automaticity. Their rhythm clearly differed from that of the surrounding fetal mouse cardiomyocytes. The number of beating cardiomyocytes increased until 3 weeks. hMSCs clearly exhibited differentiated cardiomyocyte phenotypes in vitro as revealed by immunocytochemistry, RT‐PCR, and action potential recording.

Conclusions

The life span of hMSCs was prolonged without interfering with cardiomyogenic differentiation. hMSCs with an extended life span can be used to produce a good experimental model of cardiac cell transplantation and may serve as a highly useful cell source for cardiomyocytic transplantation. Copyright © 2004 John Wiley & Sons, Ltd.
Impact assessment of microfinance using qualitative data: communicating between social scientists and practitioners using the QUIP
Authors: Wright Katie , Copestake James
Published: March 2004

Section 1 sets the context in which a qualitative impact protocol (QUIP) was created by distinguishing between demand from within microfinance organizations (MFOs) for organizational development and from donors and regulators for public policy purposes. On the supply side, it is argued that there is a case for using rigorous qualitative methods that stand between ‘positivist/quantitative’ and ‘participatory/interpretative’ approaches.

Section 2 charts how the QUIP has been developed using theImp‐Actprogramme network. It discusses the theoretical considerations that were taken into account when designing the protocol, and the developments that led to the generation of a step‐by‐step guide. It then discusses relations between social scientists and practitioners with regard to impact assessment, and suggests that the QUIP can be used to strengthen them. Copyright © 2004 John Wiley & Sons, Ltd.
Role of microfinance in the household reconstruction process in Bosnia and Herzegovina
Authors: Matul Michal , Tsilikounas Caroline
Published: March 2004

This study looks at the role micro‐enterprise lending have played in the household reconstruction process during 1996–2002 in Bosnia and Herzegovina (BiH). Bosnian households were severely affected by the conflict that resulted in destruction of household financial, physical, human and social assets leading to significant increase in household vulnerability to risks. This vulnerability is at the core of the research framework. We analyze critical household needs in BiH post‐conflict environment in order to understand how people coped with them and to what extent these efforts impacted their vulnerability. This paper claims that micro‐enterprise credit in BiH stimulated household reconstruction as it provided an efficient and long lasting coping mechanism for households after the war. For most clients micro‐enterprise credit helped at least to sustain their household self‐employment activities. Income generated from micro‐enterprises was perceived during the research as the most efficient coping mechanism among households affected by conflict so as to fill some of their most important needs over the reconstruction period. It is unquestionable that the success of a sustainable microfinance sector development has been due to the implementation of a structured and standardized minimalist approach. However, on the basis of the results presented in this paper, it appears that microfinance and related services could play a more substantial reconstruction role in post‐conflict areas. A thorough analysis of household needs informs that in BiH there was a significant need for other credit and business development services. Therefore, this paper claims that there is a need for a more integrated approach including various financial and non financial services in post‐conflict settings. As each conflict destruction and consequent reconstruction is very specific, the elements of this package will slightly differ across settings given the critical, priority needs to be satisfied. The integrated approach challenges the goal of reaching high profits in the short‐term while providing grounds to advocate for reasonable social returns over the entire reconstruction period. If a policy framework that balances financial and social returns in a longer period of time is in place the integrated approach does not preclude a development of a strong sustainable microfinance sector in the longer term. Copyright © 2004 John Wiley & Sons, Ltd.
Group dynamics, gender and microfinance in Bolivia
Authors: Velasco Carmen , Marconi Reynaldo
Published: March 2004

This paper examines the wider impacts, or externalities, of microfinance in Bolivia, an environment in which the loss of confidence in the formal banking system and the proactive role of the Superintendencia de Bancos in converting NGOs into deposit‐taking institutions have been positive factors. Our focus is on the group‐lending technology of ProMujer, which practises a ‘credit plus’ technology in which training, health and advisory services for women only are linked with lending (and savings services through FIE). There is some preliminary evidence that such groups have achieved the externality of stimulating collective public action outside of the immediate microfinance context (for example by lobbying for better public services or changes in policy); such growth seems to happen most readily where the group has collective experience of adversity, and/or where intragroup equality is high. They also have exemplary repayment rates, which—unlike those of most other microfinance institutions—did not fall off during the recent recession. This creates a second externality for the economy as a whole—a contribution to macro‐economic stability. We hypothesise that the chain of causation goes from ProMujer's ‘credit plus’ ancillary services, to client loyalty to the institution, to high repayment rates, to ability to expand lending and investment. Copyright © 2004 John Wiley & Sons, Ltd.
Microfinance, labour markets and poverty in Africa: a study of six institutions
Authors: Mosley Paul , Rock June
Published: March 2004

We examine a range of six African microfinance institutions with a view to assessing and if possible enhancing their poverty impact. The impact of microfinance loans is variable between institutions, with a tendency in particular for savings services to be taken up by people well below the poverty line, especially in South Africa and Kenya.

However, many benefits to the poor from microfinance programmes, in Africa at least, are likely to come via an indirect route, via ‘wider impacts’ or ‘spin‐offs’, rather than by through direct impacts on borrowers. We examine, here, three of these indirect routes:

(i) Microcredit to the nonpoor can reduce poverty by sucking very poor people into the labour market as employees of microfinance clients. This mechanism is important in three of our survey countries in particular (South Africa, Uganda and Kenya);

(ii) Microcredit, whether or not the proximate recipient is poor, often enhances human capital through increased expenditures on education and related improvements in health, which may then extend to poor individuals through intrahousehold and inter‐generational effects.

(iii) Microcredit, whether or not the proximate recipient is poor, often improves the household's risk management capacity through the enhancement of social capital, partly achieved by deliberate training and capacity‐building efforts and partly through fungibility of loan proceeds into the building up of social networks. This in turn may lead to ‘poverty externalities’ through the extension of credit groups to include poor people, and through the stabilisation of village income, which reduces the vulnerability of the poorest to risk. In all of our case studies, many male and female beneficiaries are members of farmer groups and/or business associations; they share information on markets, prices and technology and cut costs by pooling resources for transporting goods to and from markets and by sharing storage facilities; often borrowers invest in this form of social capital, on which drawings can be made by poor people outside the borrower population, using the proceeds of their loan.

We examine, in a non‐rigorous way, the magnitude of these ‘wider impacts’, and in a concluding section examine how they may be developed and expanded by means of institutional and policy initiatives. Copyright © 2004 John Wiley & Sons, Ltd.
Laser spray: electric field‐assisted matrix‐assisted laser desorption/ionization
Authors: Hiraoka Kenzo
Published: March 2004

A new liquid chromatography/mass spectrometry interface, the laser spray, has been developed. Explosive vaporization and mist formation occur when an aqueous solution effusing out from the tip of the stainless‐steel capillary is irradiated from the opposite side of the capillary by a 10.6 µm infrared laser. Weak ion signals could be detected when the plume was sampled through the ion sampling orifice. When a high voltage (3–4 kV) was applied to the stainless‐steel capillary, strong ion signals appeared. The ion abundances were found to be orders of magnitude greater than those obtained by conventional electrospray ionization in the case of aqueous solutions. The present method is regarded as an electric‐field assisted form of matrix‐assisted laser desorption/ionization in which the liquid chromatographic solvent (water, etc.) acts as a liquid matrix. Laser spray ionization is expected to become a versatile method for biological mass spectrometry because this method is compatible with the natural solvent, water. Copyright © 2004 John Wiley & Sons, Ltd.
Mass spectrometry in the structural analysis of flavonoids
Authors: Cuyckens Filip , Claeys Magda
Published: March 2004

The original article to which this Erratum refers was published in J. Mass Spectrom. 2004; 39 (1): 1–15. DOI:10.1002/jms.585. Copyright © 2004 John Wiley & Sons, Ltd.
Effects of soil bulk density on seminal and lateral roots of young maize plants (Zea mays L.)
Authors: Kuchenbuch Rolf O. , Ingram Keith T.
Published: March 2004

It is well established that increasing soil bulk density (SBD) above some threshold value reduces plant root growth and thus may reduce water and nutrient acquisition. However, formation and elongation of maize seminal roots and first order lateral (FOL) roots in various soil layers under the influence of SBD has not been documented. Two studies were conducted on a loamy sand soil at SBD ranging from 1.25 g cm–3 to 1.66 g cm–3. Rhizotrons with a soil layer 7 mm thick were used and pre‐germinated plants were grown for 15 days. Over the range of SBD tested, the shoot growth was not influenced whereas total root length was reduced by 30 % with increasing SBD. Absolute growth rate of seminal roots was highest in the top soil layer and decreased with increasing distance from the surface. Increasing SBD amplified this effect by 20 % and 50 % for the top soil layer and lower soil layers, respectively. At the end of the experiment, total seminal roots attributed to approximately 15 % of the total plant root length. Increasing SBD reduced seminal root growth in the lowest soil layer only, whereas FOL root length decreased with SBD in all but the uppermost soil layer. For FOL, there was a positive interaction of SBD with distance from the soil surface. Both, increasing SBD and soil depth reduced root length by a reduction of number of FOL roots formed while the length of individual FOL roots was not influenced. Hence, increasing SBD may reduce spatial access to nutrients and water by (i) reducing seminal root development in deeper soil layers, aggravated by (ii) the reduction of the number of FOL roots that originate from these seminal roots.
Added nitrogen interaction as affected by soil nitrogen pool size and fertilization – significance of displacement of fixed ammonium
Authors: Lin Shan , Dittert Klaus , Wu Wen‐Liang , Sattelmacher Burkhard
Published: March 2004

Displacement of NH4+ fixed in clay minerals by fertilizer 15NH4+ is seen as one mechanism of apparent added nitrogen interactions (ANI), which may cause errors in 15N tracer studies. Pot and incubation experiments were carried out for a study of displacement of fixed NH4+ by 15N‐labeled fertilizer (ammonium sulfate and urea). A typical ANI was observed when 15N‐labeled urea was applied to wheat grown on soils with different N reserves that resulted from their long‐term fertilization history: Plants took up more soil N when receiving fertilizer. Furthermore, an increased uptake of 15N‐labeled fertilizer, induced by increasing unlabeled soil nitrogen supply, was found. This ANI‐like effect was in the same order of magnitude as the observed ANI. All causes of apparent or real ANI can be excluded as explanation for this effect. Plant N uptake‐related processes beyond current concepts of ANI may be responsible. NH4+ fixation of fertilizer 15NH4+ in sterilized or non‐sterile, moist soil was immediate and strongly dependent on the rate of fertilizer added. But for the tested range of 20 to 160 mg 15NH4+‐N kg–1, the NH4+ fixation rate was low, accounting for only up to 1.3 % of fertilizer N added. For sterilized soil, no re‐mobilization of fixed 15NH4+ was observed, while in non‐sterile, biologically active soil, 50 % of the initially fixed 15NH4+ was released up to day 35. Re‐mobilization of 15NH4+ from the pool of fixed NH4+ started after complete nitrification of all extractable NH4+. Our results indicate that in most cases, experimental error from apparent ANI caused by displacement of fixed NH4+ in clay is unlikely. In addition to the low percentage of only 1.3 % of applied 15N, present in the pool of fixed NH4+ after 35 days, there were no indications for a real exchange (displacement) of fixed NH4+ by 15N.
Detection and localization of protein modifications by high resolution tandem mass spectrometry
Authors: Meng Fanyu , Forbes Andrew J. , Miller Leah M. , Kelleher Neil L.
Published: March 2004

For interrogation of peptides with diverse modifications, no other instrument is as versatile as the Fourier‐transform mass spectrometer (FTMS). Particularly using electrospray ionization (ESI), many intact proteins and their proteolytic products harboring post‐translational and chemical modifications (PTMs) have been studied by high resolution tandem mass spectrometry (MS/MS). The widely touted analytical figures of merit for FTMS in fact have translated into clarity when analyzing PTMs from phosphorylations to disulfides, oxidations, methylations, acetylations, and even exotic PTMs found in the biosynthesis of antibiotics and other natural products. A top down approach to PTM detection and localization is proving extensible to an increasing variety of PTMs, some of which are stable to MS/MS at the protein level but unstable to amide bond cleavage by threshold dissociations at the level of small peptides <3 kDa. In contrast, MS/MS using electron capture dissociation (ECD) allows precise localization of even labile PTMs given enough sample and abundant molecular ions. Finally, this brief synopsis of recent literature highlights specific PTMs that perturb the protein backbone therefore altering MS/MS fragmentation patterns. Thus, FTMS will continue its expansion into more laboratories in part because of its ability to detect and deconvolute the regulatory mechanisms of biology written in the language of PTMs. © 2004 Wiley Periodicals, Inc., Mass Spec Rev 24:126–134, 2005
Proteomics by FTICR mass spectrometry: Top down and bottom up
Authors: Bogdanov Bogdan , Smith Richard D.
Published: March 2004

This review provides a broad overview of recent Fourier transform ion cyclotron resonance (FTICR) applications and technological developments relevant to the field of proteomics. Both the “bottom up” (peptide level) and “top down” (intact protein level) approaches are discussed and illustrated with examples. “Bottom up” topics include peptide fragmentation, the accurate mass and time (AMT) tag approach and dynamic range extension technology, aspects of quantitative proteomics measurements, post‐translational modifications, and developments in FTICR operation software focused on peptide and protein identification. Topics related to the “top down” approach include various aspects of high mass measurements, protein tandem mass spectrometry, methods for the study of protein conformations, and protein complexes as well as advanced technologies that may become of practical utility in the coming years. Finally, early examples of the integration of both FTICR approaches to biomedical proteomics applications are presented, along with an outlook for future directions. © 2004 Wiley Periodicals, Inc., Mass Spec Rev 24:168–200, 2005
Effects of triploidy on early human development
Authors: Philipp T. , Grillenberger K. , Separovic E. R. , Philipp K. , Kalousek D. K.
Published: March 2004

Objective

The morphologic features of 18 triploid embryos are described.

Method

Embryoscopic examination of the embryo in cases of missed abortion before instrumental evacuation from the uterus. Cytogenetic and histologic analysis of the chorionic villi.

Results

Seventeen out of 18 triploid embryos showed structural defects on embryoscopic examination. The most common defects were facial anomalies (n = 15), limb abnormalities (n = 13), microcephaly (n = 11) and neural tube defects (n = 10); 3 embryos were classified as growth disorganized. Placenta of 12 grossly abnormal embryos was diagnosed as partial hydatidiform moles on histological examination.

Conclusions

The grossly abnormal development of the embryo observed in 12 partial hydatidiform moles indicate that, in aborted triploid embryos, the presence of two paternal genomes might have both placental and embryonic consequences. Transcervical embryoscopy in cases of missed abortion can serve as a central component in additional studies using molecular determination of parental origin of triploidy to establish the true proportion of diandric triploidy among grossly abnormal triploid embryos. Copyright © 2004 John Wiley & Sons, Ltd.
Pregnancy after preimplantation genetic diagnosis for Sanjad–Sakati syndrome
Authors: Hellani Ali , Aqueel Aida , Jaroudi Kamal , Ozand Pinar , Coskun Serdar
Published: March 2004

Sanjad–Sakati syndrome (SSS) is an autosomal recessive disorder characterized by congenital hypoparathyroidism, growth and mental retardation. In Saudi Arabia, the disease is caused by a deletion of 12 bp (155‐166nt) in the tubulin‐specific chaperone E gene. In a family with two affected siblings with SSS, preimplantation genetic diagnosis (PGD) was performed. Fluorescent PCR (F‐PCR) was utilized to check the heterozygosity and the homozygosity status of the parents and the affected children, respectively. F‐PCR was then optimized for single‐cell analysis by using peripheral blood lymphocytes. The patient underwent a cycle with intra‐cytoplasmic sperm injection. A total of 11 embryos were obtained and biopsied. There were five heterozygous, three homozygous affected and three normal embryos. One heterozygous and one normal embryo were transferred because of their very good quality (morula). A singleton pregnancy was obtained, and amniosynthesis confirmed the presence of the heterozygous fetus. These results show for the first time, the feasibility of PGD for SSS. Copyright © 2004 John Wiley & Sons, Ltd.
Cell‐free fetal DNA (SRY locus) concentration in maternal plasma is directly correlated to the time elapsed from the onset of preeclampsia to the collection of blood
Authors: Farina Antonio , Sekizawa Akihiko , Rizzo Nicola , Concu Manuela , Banzola Irina , Carinci Paolo , Simonazzi Giuliana , Okai Takashi
Published: March 2004

Objective

To determine (1) if fetal DNA (fDNA) in the maternal circulation in women affected by preeclampsia correlates with the time elapsed from the onset of symptoms to the time of blood collection, and (2) if the inclusion of this variable improves the discrimination between affected and unaffected patients by using fDNA distributions.

Methods

Plasma were collected from 34 women at 33.7 ± 3.9 weeks' gestation, affected by preeclampsia, and bearing a single male fetus. fDNA was extracted from 1.5‐mL plasma samples, and the SRY and β‐globin gene were analyzed by real‐time quantitative PCR. MoMs (multiple of the control median) were calculated by using a log equation of 102 normal cases. Log MoMs were then plotted against the time elapsed from onset of symptoms to blood collection (expressed in days) by means of a log‐linear regression. Adjusted MoMs were then calculated. ROC curves were used to test the discrimination obtained by using adjusted MoMs.

Results

The median MoMs of controls and preeclamptic patients were 1.00 ± 1.53 and 2.62 ± 2.70 respectively. By plotting log MoM fDNA against the time elapsed from onset of symptoms to blood collection, we found a significant positive correlation, (p‐value < 0.001, R2 = 0.55, F = 38.97, from 1 to 50 days). The adjusted median fDNA MoM was 2.66 ± 2.50. Areas under the curves, as estimated by ROC curves, were 76.7 for unadjusted and 85.5 for adjusted MoMs respectively (p‐value = 0.02).

Conclusions

The effect of a further covariate showed that (1) fDNA passage from trophoblasts to maternal circulation for unit of time is proportional to the duration of the damage and that (2) increased discrimination can be obtained in comparison to normal subjects. Copyright © 2004 John Wiley & Sons, Ltd.
Structure and properties of an oriented fluorosulfonated/PTFE copolymer
Authors: Gilbert M. , Haworth B. , Myers D. J. B.
Published: March 2004

This polymer is a precursor of Nafion, an ionomer developed for ion‐selective membranes. In this work various stretching procedures were carried out on the precursor, in order to explore the possibilities of enhanced performance. First, the crystallization behavior and properties of the unoriented precursor were investigated. It was found that the precursor copolymer contains crystallinity, which melts over a very wide temperature range. The amount of crystallinity is modified both by thermal history and applied shear. Thermal analysis can be used to determine processing/annealing temperatures for samples with unknown thermal history. It was found that the precursor possessed a maximum elongation at break at 70°C. Stretching was carried out at 70°C using a laboratory‐based tentering process, to produce both uniaxial and biaxial films. Films were characterized to monitor their shrinkage behavior, and orientation was measured by birefringence. Their tensile properties were measured with respect to stretching direction. Using tentering, which is carried out at relatively low temperatures, large amounts of orientation were produced, resulting in a significant increase in tensile strength, and decrease in elongation at break.
Effects of carbon nanotubes on the crystallization behavior of polypropylene
Authors: Valentini L. , Biagiotti J. , López‐Manchado M. A. , Santucci S. , Kenny J. M.
Published: March 2004

The effect of the incorporation of single‐walled carbon nanotubes (SWNTs) on the PP crystallization kinetics is investigated by thermal analysis, microscopy and Raman spectroscopy. The results of the investigation show that SWNT acts as a strong nucleation agent. A marked decrease of the half‐time of PP crystallization as well as a sensible increase of the overall crystallization rate is observed in the presence of SWNTs. Moreover, these effects are already noticeable at the lowest SWNT content in the composite with slow further effects at higher concentrations, suggesting a saturation of the nucleating action at the higher concentrations studied. The Avrami model can represent the crystallization kinetics of PP in the composite. The kinetic curves obtained under non‐isothermal conditions confirm the results obtained in isothermal tests and demonstrate the nucleation ability of SWNTs on the PP crystallization. Raman spectroscopy and scanning electron microscopy (SEM) are successfully applied to demonstrate that in the composite films, the changes in the crystallization kinetics can be explained in terms of the changes of the distance between nanotubes in bundles following a different intercalation of the polymer matrix.
Structure modification of isotactic polypropylene by bi‐component nucleating systems
Authors: Sterzynski Tomasz , Øysæd Harry
Published: March 2004

The efficiency of heterogeneous nucleation of isotactic polypropylenes (iPP) with various isotacticity and MWD is estimated by an increase of the crystallization temperature (Tcr). A bi‐component nucleating system, composed of a pimelic acid and a calcium stearate, was added to the polymeric matrix in the molten state. The relative increase of Tcr is found to be independent on the structure stereo‐regularity of iPP. On the contrary, dependent on the polymer structure, the investigated nucleating system influences in a different way the creation of the β‐phase. The form of the DSC melting curves, for the β‐phase rich iPP samples, is discussed in terms of various preliminary cooling conditions. The transformation from a multi‐modal form of the DSC melting peak to a simple one is related to the lowering of the cooling rate and to the increase of the heating rate.
A proteomic view of cell physiology of Bacillus licheniformis
Authors: Voigt Birgit , Schweder Thomas , Becher Dörte , Ehrenreich Armin , Gottschalk Gerhard , Feesche Jörg , Maurer Karl‐Heinz , Hecker Michael
Published: March 2004

The still ongoing sequencing of Bacillus licheniformis at the Göttingen Sequencing Laboratory provides the basis for proteome studies of the bacterium. By using two‐dimensional (2‐D) electrophoresis and protein identification by mass spectrometry, we were able to create master gels for B. licheniformis cells grown either in minimal medium or in complex medium containing about 300 and 180 entries, respectively. With the DECODON Delta 2D software we identified the most abundant protein spots on the gels, which were shown to perform mainly basic metabolic functions in the cell such as translation, amino acid metabolism, glycolysis, and tricarboxylic acid (TCA) cycle. Based on the master gels, we were able to study the regulation of metabolic pathways such as glycolysis and TCA cycle. In cells grown in the presence of glucose a significant increase of the amount of some glycolytic enzymes (TpiA, GapA, Pgk, Pgm, Eno, Pyk) and of the pyruvate dehydrogenase (PdhA‐D) was found. At the same time, there is a strong repression of almost all TCA cycle enzymes and of the ATP synthase. Glucose also stimulates the acetate kinase (AckA) and the phosphotransacetylase (Pta) which are known to be involved in the overflow metabolism in B. subtilis. Furthermore, we began developing proteomic signatures for growth of B. licheniformis in complex medium. For this purpose, we compared the proteome pattern of exponentially growing cells with that of cells in different stages during stationary phase. The most obvious proteomic signature indicates that cells during stationary phase are subjected to a severe oxidative stress and a resulting protein stress. Furthermore, the level of many vegetative proteins is strongly reduced when the growth is arrested after entry into stationary phase. The data indicate that proteomics can be a valuable tool to describe the physiological state of B. licheniformis cell populations, e.g., of cells growing in a bioreactor.
Brain proteome of mice lacking the receptors for tumor necrosis factor α
Authors: Pejović Vojislav , Šoškić Vukić , Pan Weihong , Kastin Abba J.
Published: March 2004

Tumor necrosis factor α (TNFα) is involved in regulation of food intake, inflammatory response, and cancer cachexia. Its actions are mediated by at least two receptors: TNFR1 and TNFR2. We show that mice lacking the TNFα receptors have altered levels of proteins that take part in signal transduction, stress response, protein folding, glucose and amino acid metabolism, vesicle trafficking, and cytoskeletal arrangements. This is the first time that some of them have been associated with TNFα signaling pathways.