bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensitization to Empynase®(pronase B) in exposed hospital personnel and identification of the Empynase® allergen
Authors: Bahn J.‐W. , Lee J.‐Y. , Jang S.‐H. , Kim S.‐H. , Kim H.‐M. , Park H.‐S.
Published: February 2006

Background
Empynase® is a proteolytic enzyme that is widely used as an anti‐inflammatory drug in Korea. We evaluated the prevalence of sensitization to Empynase® in association with respiratory allergy symptoms in exposed hospital personnel, and identified the IgE‐binding components in the Empynase® extract, using sera with high levels of specific IgE antibodies.

Methods
A total of 154 hospital personnel (135 nurses and 19 pharmacists) who worked in a university hospital and 123 unexposed healthy control subjects were enrolled. A questionnaire was administered that addressed demographics, job category, history of atopic diseases, diverse symptoms including nasal and lower respiratory symptoms, and the association of symptoms with work. Skin prick tests (SPTs) to common aeroallergens and Empynase® extract were performed. Empynase®‐specific IgE antibody was detected by ELISA, and ELISA inhibition tests were conducted. IgE‐binding components were identified by SDS‐PAGE and IgE immunoblotting.

Results
Forty‐two subjects (27.3%) complained of work‐related respiratory symptoms (WRRS). Five nurses (3.7%) and one pharmacist (5.3%) had work‐related asthma symptoms, and 34 nurses (25.2%) and six pharmacists (31.6%) had work‐related rhinitis symptoms. The prevalence of sensitization to Empynase® on SPTs was 20.1%, and tended to be higher in pharmacists (31.6%) than in nurses (18.5%). It was estimated that 3.9–8.4% of hospital personnel had WRRS attributable to Empynase®. The duration of exposure was longer in positive SPT responders than in negative responders (51.9±27.5 vs. 39.2±27.3 months, respectively; P<0.05), and the prevalence of Empynase®‐positive SPTs was significantly higher in subjects with asthma than in those without asthma (57.1% vs. 18.4%, respectively; P<0.05). The levels of Empynase®‐specific IgE antibodies were significantly higher in pharmacists (76.1±83.4 OD units) and nurses (56.3±103.0 OD units) than in normal controls (39.8±12.7 OD units; P<0.05). Seven subjects (two pharmacists and five nurses) had high serum levels of Empynase®‐specific IgE antibodies; six of these subjects had WRRS. ELISA inhibition tests were performed with the sera of these six subjects, revealing significant inhibition only with the addition of Empynase®. Four strongly staining protein bands (sizes: 36, 33, 16, and 10 kDa) from Empynase® extract were observed to bind to the IgE antibodies of sensitized subjects.

Conclusion
Exposure to Empynase® powder may cause rhinitis and asthma in hospital personnel, and the pathogenic mechanism appears to be IgE mediated.
Natural and recombinant molecules of the cherry allergen Pru av 2 show diverse structural and B cell characteristics but similar T cell reactivity
Authors: Fuchs H. C. , Bohle B. , Dall'Antonia Y. , Radauer C. , Hoffmann‐Sommergruber K. , Mari A. , Scheiner O. , Keller W. , Breiteneder H.
Published: February 2006

Background
Cherry allergy is often reported in the context of allergy to other fruits of the Rosaceae family and pollinosis to trees because of cross‐reactive allergens. Allergic reactions to cherry are reported by 19–29% of birch pollen‐allergic patients. Pru av 2, identified as a thaumatin‐like protein (TLP) from sweet cherry, was recognized by the majority of cherry‐allergic patients in immunoblotting.

Objectives
In order to investigate the structural characteristics and the immunoglobulin (Ig)E‐ and T cell reactivity of cherry‐derived TLP, recombinant Pru av 2 was expressed in Escherichia coli and natural Pru av 2 was purified.

Methods
Parallel‐His and FLAG expression vectors were used for recombinant production of Pru av 2 in the cytoplasm and the periplasm of E. coli. Natural Pru av 2 was purified from fresh cherries and verified by N‐terminal sequencing. Structural characterization was performed using circular dichroism (CD) measurements, and the biologic activity was measured in a glucanase assay. Using cherry‐specific sera, the IgE‐binding ability of recombinant and natural Pru av 2 was investigated in IgE‐ELISA and the T cell reactivity was studied in proliferation assays.

Results
Natural Pru av 2 revealed thaumatin‐like structural features and bound IgE of 50% of cherry‐allergic patients. It was demonstrated to be enzymatically active. Recombinant Pru av 2 expressed in the cytoplasm of E. coli exhibited a slightly different folding compared with the natural protein. It was not recognized by IgE from cherry‐allergic subjects, but retained the ability to stimulate T lymphocytes. Periplasmic recombinant Pru av 2 was able to bind an anti‐grape TLP antibody and cherry‐specific IgE.

Conclusions
We prepared two recombinant model TLPs from cherry, and compared their molecular characteristics as well as their IgE‐binding activity and T cell interactions in relation to the natural counterpart. The cytoplasmic recombinant Pru av 2 can be used as a hypoallergenic variant in allergen‐specific immunotherapy, whereas the periplasmic protein can be included in a component‐resolved diagnosis.
Inhibition of rBet v 1‐induced basophil histamine release with specific immunotherapy ‐induced serum immunoglobulin G: no evidence that FcγRIIB signalling is important
Authors: Ejrnaes A. M. , Svenson M. , Lund G. , Larsen J. N. , Jacobi H.
Published: February 2006

Background
Human basophils and mast cells express the low‐affinity immunoglobulin (Ig)G receptor FcγRIIB. It has previously been shown in artificial model systems that cross‐linking of the high‐affinity IgE receptor FcɛRI and FcγRIIB leads to inhibition of FcɛRI signalling.

Objective
The aim of the present study was to investigate whether cross‐linking of FcɛRI and FcγRIIB contributes to IgG‐mediated inhibition of histamine release in human basophils in a system using the sera from specific immunotherapy (SIT) patients and the major allergen from birch pollen, Bet v 1. As IgG4 furthermore has been proposed to have special blocking properties, we investigated the significance of IgG subclass specificity for this inhibition.

Methods
Binding of recombinant Bet v 1–IgG complexes to FcγRII and IgG‐binding activities in the sera from 25 birch pollen‐allergic patients treated with SIT were measured using 125I‐rBet v 1. Inhibition of basophil histamine release was assessed by incubating washed leucocytes with complexes of rBet v 1–IgG with or without blocking of FcγRII.

Results
We observed low binding of rBet v 1–IgG complexes to FcγRII, which was negatively correlated with the relative IgG4‐binding activities. Blocking of FcγRII did not reverse the SIT–IgG‐induced inhibition of basophil histamine release. However, IgG‐binding activities correlated significantly with the ability of the SIT sera to inhibit basophil histamine release.

Conclusion
We suggest that at least in birch pollen SIT, the contribution of FcγRIIB‐mediated inhibitory signalling to SIT–IgG‐induced inhibition of human basophil histamine release is of minor importance. The main contributor to the inhibitory effect of SIT‐induced IgG seems to be blocking of the allergen–IgE interaction.
4‐1BB stimulation inhibits allergen‐specific immunoglobulin E production and airway hyper‐reactivity but partially suppresses bronchial eosinophilic inflammation in a mouse asthma model
Authors: Cho Y. S. , Kwon B. , Lee T.‐H. , Kim T.‐B. , Moon K.‐A. , La S. , Lee J. , Lee S. D. , Oh Y.‐M. , Moon H.‐B.
Published: February 2006

Background
4‐1BB, a member of the tumour necrosis factor receptor superfamily, functions as a co‐stimulatory molecule. Recently, stimulation of the 4‐1BB pathway was shown to suppress antigen‐specific CD4+ T cell and subsequent T cell‐dependent humoral immune responses.

Objective
We examined the effect of agonistic anti‐4‐1BB monoclonal antibody (mAb) treatment on allergic asthma, in which allergen‐specific type 2 helper T cells (Th2) have been shown to play an important role.

Methods
BALB/c mice were systemically sensitized with intraperitoneal injections of ovalbumin (OVA) and alum on days 0 and 14, and then challenged with inhaled OVA on days 28, 29 and 30. In test groups, the agonistic anti‐4‐1BB mAb was administered at the time of initial systemic sensitization with OVA. On day 31, mice were challenged with inhaled methacholine, and enhanced pause was measured as an index of airway hyper‐responsiveness (AHR). Levels of OVA‐specific IgE in serum, and levels of various cytokines in bronchoalveolar lavage (BAL) fluids were measured. The severity of airway inflammation was determined by differential cell counts in BAL fluids and histopathologic lung analysis. To evaluate local immunity, we cultured lymphocytes from draining perihilar lymph nodes and evaluated the proliferative response to OVA and the levels of IL‐5 in the culture supernatant. In addition, the functional mechanism of 4‐1BB stimulation was evaluated in splenocytes obtained at day 7 after systemic OVA sensitization.

Results
We found that treatment with the anti‐4‐1BB mAb significantly decreased AHR and the production of allergen‐specific IgE. Bronchial inflammation, however, had only partially improved and the levels of IL‐4 and IL‐5 in BAL fluids showed only a small degree of reduction compared with the control Ig‐treated mice. Thoracic lymphocytes from anti‐4‐1BB‐treated mice showed significant suppression of OVA‐induced proliferation and IL‐5 production. In anti‐4‐1BB‐treated mice, splenocytes exhibited poor proliferation and marked apoptosis 7 days after systemic OVA challenge.

Conclusion
These results suggest that stimulation of the 4‐1BB pathway effectively suppresses some features of allergic asthma, including allergen‐specific IgE production and AHR, through deletion of allergen‐specific Th2 cells. However, we found that bronchial allergic inflammation was not strictly mediated by suppression of the Th2 immune response in this murine model of asthma. Despite these somewhat contradictory effects, intervention in the 4‐1BB pathway might provide a potential novel immunotherapeutic approach for treatment of allergic asthma.
Characterization of glutathione S‐transferase from dust mite, Der p 8 and its immunoglobulin E cross‐reactivity with cockroach glutathione S‐transferase
Authors: Huang C. H. , Liew L. M. , Mah K. W. , Kuo I. C. , Lee B. W. , Chua K. Y.
Published: February 2006

Background
Sensitization to mite and cockroach allergens is common, and diagnosis and therapy of allergy can be further complicated by the presence of allergen isoforms and panallergens. Purified recombinant and native allergens are useful for studies to resolve such problems.

Objective
To assess the allergenicity of native and recombinant mite glutathione S‐transferase (GST) (Der p 8) and study the IgE cross‐reactivity between Der p 8 and cockroach GST.

Methods
Der p 8 cDNA encoding a new isoform was isolated and expressed in yeast. Native Der p 8 was affinity purified from mite extract. IgE reactivity to native and recombinant Der p 8 was assessed by ELISA using sera from allergic subjects from Taiwan, Singapore and Malaysia. IgE cross‐reactivity between Der p 8 and cockroach GST was examined by IgE inhibition assays.

Results
Our Der p 8 cDNA encoded a basic isoform (pI=8.5) containing six polymorphic residues located at positions 46, 106, 149, 160, 167 and 184. At least 8 isoforms of native Der p 8 were detected by two‐dimensionalgel and immunoblot analyses. Sera from Taiwanese asthmatics showed 96% and 84% IgE reactivity to native Der p 8 and recombinant Der p 8, respectively. Native Der p 8 showed 75% and 65% IgE reactivity with sera from Malaysia and Singapore, respectively.

Conclusions
A high frequency of sensitization to mite GST among allergic subjects was observed but the titres of IgE reactivity were low. The IgE cross‐reactivity between mite and cockroach GST suggests that GST is a panallergen.
Intranasal steroid reduces exhaled bronchial cysteinyl leukotrienes in allergic patients
Authors: Failla M. , Biondi G. , Provvidenza Pistorio M. , Gili E. , Mastruzzo C. , Vancheri C. , Crimi N.
Published: February 2006

Background
Allergic rhinitis (AR) precedes and is often associated with bronchial asthma. Indeed, local and systemic inflammations in both conditions are very similar. Cysteinyl‐leukotrienes (cys‐LTs) are generated during early‐ and late‐phase allergic reactions and induce smooth‐muscle contraction, microvascular leakage, and mucous hypersecretion. Cys‐LTs are detected in exhaled breath condensate (EBC) of asthmatics and regardless of bronchial symptoms, they are also found in EBC of rhinitic patients.

Objective
To evaluate cys‐LTs in EBC of allergic patients and to assess the activity of nasal fluticasone propionate (FP) on EBC cys‐LTs levels.

Methods
Cys‐LTs coefficient of variation (CV) was evaluated from different EBC in 5 healthy volunteers. Cys‐LTs levels from EBCs in 13 healthy controls and 56 allergic rhinitic (n=31) and rhinitic/asthmatic (n=25) patients were also evaluated at baseline. Subsequently patients were randomized to receive either FP 100 μg/day per nostril or placebo for 2 weeks and then re‐evaluated for EBC cys‐LTs.

Results
The CV was 14.12%. EBC cys‐LTs in allergic patients were significantly higher than in healthy subjects (70.9  vs. 20.6 pg/mL (median), P<0.05), while it did not differ between asthmatic/rhinitic and purely rhinitic patients. Treatment significantly reduced cys‐LTs (from 93.6 to 19.9 pg/mL, P<0.001). This effect was evident both in asthmatic/rhinitic and in rhinitic patients.

Conclusion
Treatment of AR with FP significantly reduces the levels of cys‐LTs, major noninvasive markers of lower airway inflammation, suggesting that upper and lower airway inflammation is present and should be thus treated as a whole in subjects with AR with and without asthma.
Impaired virus‐induced interferon‐α2 release in adult asthmatic patients
Authors: Gehlhar K. , Bilitewski C. , Reinitz‐Rademacher K. , Rohde G. , Bufe A.
Published: February 2006

Background
Interferon‐α (IFN‐α) not only serves as a first defence line of the immune system against viral attacks but also interacts with T‐helper type 1 (Th1)/ T‐helper type 2 (Th2) regulation and various other cell types like basophils and monocytes, thereby linking innate and acquired immunity. Recently, we demonstrated that children with allergic asthma produced significantly lower amounts of virus‐induced IFN‐α2 compared with healthy children or those with intrinsic asthma.

Objective
In this study, we extend our analysis to examine in a cohort study whether IFN‐α2 is also reduced in allergic asthma of adults.

Methods
Adults with allergic asthma and healthy controls were prospectively recruited. Blood cultures were stimulated with different viruses (respiratory syncytial virus (RSV), newcastle disease virus (NDV)) and analysed for IFN‐α2 protein release and gene transcription.

Results
Virus‐induced IFN‐α2 release from blood cells of allergic asthmatic patients was significantly reduced compared with healthy controls, independent of the virus used (NDVasthma=221±134 pg/mL, NDVhealthy=555±341 pg/mL, P=0.003 and RSVasthma=46±27 pg/mL, RSVhealthy=108±90 pg/mL, P=0.014). Values=mean±standard deviation). It was not influenced by medication, especially cortico‐steroids. IFN‐α2 mRNA expression 5 h after NDV stimulation confirmed the ELISA results and correlated well with release data (r=0.397, P=0.033).

Conclusion
Like children, adults with allergic asthma show impaired virus‐induced IFN‐α2 release in whole blood, indicating a systemic phenomenon in patients with bronchial asthma and atopic phenotype. Impaired virus‐induced IFN‐α release could be a marker of inflammation in chronic allergic asthma.
Intensity correction of fluorescent confocal laser scanning microscope images by mean‐weight filtering
Authors: LEE SANG‐CHUL , BAJCSY PETER
Published: February 2006

This paper addresses the problem of intensity correction of fluorescent confocal laser scanning microscope images. Confocal laser scanning microscope images are frequently used in medicine for obtaining 3D information about specimen structures by imaging a set of 2D cross sections and performing 3D volume reconstruction afterwards. However, 2D images acquired from fluorescent confocal laser scanning microscope images demonstrate significant intensity heterogeneity, for example, due to photo‐bleaching and fluorescent attenuation in depth. We developed an intensity heterogeneity correction technique that (a) adjusts the intensity heterogeneity of 2D images, (b) preserves fine structural details and (c) enhances image contrast, by performing spatially adaptive mean‐weight filtering. Our solution is obtained by formulating an optimization problem, followed by filter design and automated selection of filtering parameters. The proposed filtering method is experimentally compared with several existing techniques by using four quality metrics: contrast, intensity heterogeneity (entropy) in a low frequency domain, intensity distortion in a high frequency domain and saturation. Based on our experiments and the four quality metrics, the developed mean‐weight filtering outperforms other intensity correction methods by at least a factor of 1.5 when applied to fluorescent confocal laser scanning microscope images.
A new approach for improving the birefringence analysis of dental enamel mineral content using polarizing microscopy
Authors: SOUSA F. B. , VIANNA S. S. , SANTOS‐MAGALHÃES N. S.
Published: February 2006

The main problem in interpreting birefringence of dental enamel under polarizing microscopy is the lack of physical constants able to allow the Wiener equation to be applied directly to the composition of such tissue. The present study introduces a new approach to circumvent this constraint. Because the nonmineral phase of enamel is heterogeneous, its refractive index can be computed in terms of its components (namely, water, which is partially replaced by the immersion medium, and organic matter), thereby providing a more acceptable refractive index to be used in the Wiener equation. Furthermore, the enamel mineral volume is ordinarily calculated on the basis of the density 3.15 g cm−3. The density 2.99 g cm−3 has been, however, reported to be more accurate for enamel hydroxyapatite, so enamel mineral volumes from selected published data were converted using such a density. The birefringence of mature enamel computed by the Wiener equation, taking into account the above refinements, matched, for the first time, published experimental birefringence values. The theoretical water and organic contents were also consistent with published experimental data. Thus, a direct application of the Wiener equation to the enamel composition has now been achieved. It is speculated that quantitative data on the mineral, the water and the organic contents of mature dental enamel can be derived from interpretation of birefringence in two immersion media (obtained before and after extraction of the organic matter) with this new approach.
The quantitative analysis of thin specimens: a review of progress from the Cliff‐Lorimer to the new ζ‐factor methods
Authors: WATANABE M. , WILLIAMS D. B.
Published: February 2006

A new quantitative thin‐film X‐ray analysis procedure termed the ζ‐factor method is proposed. This new ζ‐factor method overcomes the two major limitations of the conventional Cliff‐Lorimer method for quantification: (1) use of pure‐element rather than multielement, thin‐specimen standards and (2) built‐in X‐ray absorption correction with simultaneous thickness determination. Combined with a universal, standard, thin specimen, a series of ζ‐factors covering a significant fraction of the periodic table can be estimated. This ζ‐factor estimation can also provide information about both the detector efficiency and the microscope–detector interface system. Light‐element analysis can also be performed more easily because of the built‐in absorption correction. Additionally, the new ζ‐factor method has several advantages over the Cliff‐Lorimer ratio method because information on the specimen thickness at the individual analysis points is produced simultaneously with compositions, thus permitting concurrent determination of the spatial resolution and the analytical sensitivity. In this work, details of the ζ‐factor method and how it improves on the Cliff‐Lorimer approach are demonstrated, along with several applications.
Three times out of Asia Minor: the phylogeography of Arabis alpina L. (Brassicaceae)
Authors: KOCH MARCUS A. , KIEFER CHRISTIANE , EHRICH DOROTHEE , VOGEL JOHANNES , BROCHMANN CHRISTIAN , MUMMENHOFF KLAUS
Published: February 2006

Arabis alpina is a characteristic plant in arctic‐alpine habitats and serves as a classical example to demonstrate biology, ecology and biogeography of arctic‐alpine disjuncts. It has a wider distribution than most other arctic‐alpine plants, covering all European mountain systems, the Canary Islands, North Africa, the high mountains of East Africa and Ethiopia, the Arabian Peninsula and mountain ranges of Central Asia in Iran and Iraq. Additionally it is found in the northern amphi‐Atlantic area including northeastern North America, Greenland, Iceland, Svalbard and northwestern Europe. We used markers from the nuclear (internal transcribed spacer of ribosomal DNA) and chloroplast genome (trnL‐F region) to reconstruct its phylogeographic history. Both markers revealed clear phylogeographic structure. We suggest that A. alpina originated in Asia Minor less than 2 million years ago based on synonymous mutation rates of different genes (plastidic matK, nuclear adh and chs). From the Asian ancestral stock one group migrated via the Arabian Peninsula to the East African high mountains. A second group gave rise to all European and northern populations, and also served as source for the northwest African populations. A third group, which is still centred in Asia, migrated independently southwards and came into secondary contact with the East African lineage in Ethiopia, resulting in high genetic diversity in this area. In the Mediterranean regions, the genetic diversity was relatively high with numerous unique haplotypes, but almost without geographic structure. In contrast, the populations in the northern amphi‐Atlantic area were extremely depauperate, suggesting very recent (postglacial) expansion into this vast area from the south.
Ecological and evolutionary genomics of Saccharomyces cerevisiae
Authors: LANDRY CHRISTIAN R. , TOWNSEND JEFFREY P. , HARTL DANIEL L. , CAVALIERI DUCCIO
Published: February 2006

Saccharomyces cerevisiae, the budding yeast, is the most thoroughly studied eukaryote at the cellular, molecular, and genetic levels. Yet, until recently, we knew very little about its ecology or population and evolutionary genetics. In recent years, it has been recognized that S. cerevisiae occupies numerous habitats and that populations harbour important genetic variation. There is therefore an increasing interest in understanding the evolutionary forces acting on the yeast genome. Several researchers have used the tools of functional genomics to study natural isolates of this unicellular fungus. Here, we review some of these studies, and show not only that budding yeast is a prime model system to address fundamental molecular and cellular biology questions, but also that it is becoming a powerful model species for ecological and evolutionary genomics studies as well.
Rare arctic‐alpine plants of the European Alps have different immigration histories: the snow bed species Minuartia biflora and Ranunculus pygmaeus
Authors: SCHÖNSWETTER P. , POPP M. , BROCHMANN C.
Published: February 2006

Minuartia biflora and Ranunculus pygmaeus are circumarctic plants with a few isolated occurrences in the European Alps. We analysed amplified fragment length polymorphism (AFLP) and chloroplast DNA sequence data to unravel the history of their immigration into the Alps and to provide data on their circumpolar phylogeography. In spite of the similar ecological requirements of the two species, they exhibit strikingly different immigration histories into the Alps. In M. biflora, the Alpine populations are most probably derived from source populations located between the Alpine and Scandinavian ice sheets, in accordance with the traditional biogeographic hypothesis. In contrast, the Alpine populations of R. pygmaeus cluster with those from the Tatra Mountains and the Taymyr region in northern Siberia, indicating that the distant Taymyr area served as source for the Alpine populations. Both species showed different levels of genetic diversity in formerly glaciated areas. In contrast to the considerable AFLP diversity observed in M. biflora, R. pygmaeus was virtually nonvariable over vast areas, with a single phenotype dominating all over the Alps and another, distantly related one dominating the North Atlantic area from Greenland over Svalbard to Scandinavia. The same pattern was observed in chloroplast DNA sequence data. Thus, postglacial colonization of R. pygmaeus was accompanied by extreme founder events.
Detecting the signature of selection on immune genes in highly structured populations of wild sheep (Ovis dalli)
Authors: WORLEY K. , CAREY J. , VEITCH A. , COLTMAN D. W.
Published: February 2006

The confounding effects of population structure complicate efforts to identify regions of the genome under the influence of selection in natural populations. Here we test for evidence of selection in three genes involved in vertebrate immune function — the major histocompatibility complex (MHC), interferon gamma (IFNG) and natural resistance associated macrophage polymorphism (NRAMP) — in highly structured populations of wild thinhorn sheep (Ovis dalli). We examined patterns of variation at microsatellite loci linked to these gene regions and at the DNA sequence level. Simple Watterson's tests indicated balancing selection at all three gene regions. However, evidence for selection was confounded by population structure, as the Watterson's test statistics from linked markers were not outside of the range of values from unlinked and presumably neutral microsatellites. The translated coding sequences of thinhorn IFNG and NRAMP are fixed and identical to those of domestic sheep (Ovis aries). In contrast, the thinhorn MHC DRB locus shows significant evidence of overdominance through both an excess of nonsynonymous substitution and trans‐species polymorphism. The failure to detect balancing selection at microsatellite loci linked to the MHC is likely the result of recombination between the markers and expressed gene regions.
Interspecies mating in sympatric species ofSyngnathuspipefish
Authors: WILSON A. B.
Published: February 2006

Hybridization is thought to be an important source of novel genetic variation, and interspecific hybridization may increase the adaptive potential of wild populations. While hybridization has not been previously reported in syngnathid fishes (seahorses and pipefish), the sympatric occurrence of closely related species at high densities increases the probability of interspecies mating in this group. Southern California is home to five species ofSyngnathuspipefish, and these species frequently co‐occur in near‐shore eelgrass beds along the California coast. Recent work has identified exceptionally high levels of genetic diversity in southern populations ofSyngnathus leptorhynchus, a widespread species which ranges from Mexico to Alaska. Microsatellite genotyping and mitochondrial sequence data are used here to study the population genetics ofS. leptorhynchusandS. auliscusat a site in San Diego Bay where they are found to co‐occur at high densities. While no adult hybrids were detected in the study population, analysis of male broods indicates that interspecies mating is occurring between the two species. The lack of premating isolating mechanisms between these two relatives suggests that hybridization may be common in sympatric species ofSyngnathus.
Adolescent non‐adherence: Prevalence and consequences in liver transplant recipients
Authors: Berquist R. K. , Berquist W. E. , Esquivel C. O. , Cox K. L. , Wayman K. I. , Litt I. F.
Published: February 2006

Abstract: Few studies have examined the prevalence, demographic variables and adverse consequences associated with non‐adherence to immunosuppressive therapy in the adolescent liver transplant population. Our hypothesis is that a significant proportion of adolescent liver transplant recipients exhibit non‐adherence to medical regimens and that certain demographic and medical condition‐related characteristics can be identified as potential predictors of non‐adherent behavior. Furthermore, non‐adherence leads to a greater incidence of morbidity and mortality in this population as compared with the adherent subset of adolescent patients. We reviewed the charts of 97 patients from 1987 to 2002 who by December of 2002 had survived at least 1 yr post‐transplant and were followed by the Pediatric Liver Transplant Service at any point during their adolescent period (ages of 12–21). Non‐adherence was defined as documentation of a report of non‐adherence by a patient, parent or healthcare provider that was recorded in the patient's legal medical record. Descriptive statistics were used to determine the prevalence, demographic variables and adverse outcomes associated with non‐adherence to immunosuppressive therapy. Categorical variables were analyzed using the chi‐square test or the Fisher exact probability test. The unpaired Student's t‐test was used to analyze the continuous variable of age at transplant. Using the inclusion criteria, a total of 97 patients represented the study sample of whom 37 subjects (38.1%) were defined as non‐adherent and 60 (61.8%) were adherent. Non‐adherent subjects were more likely to be female, older (>18 yr) and from a single‐parent household. There was no significant difference in immunosuppressive regimen between non‐adherent and adherent patients. Non‐adherence was significantly (p<0.025) associated with lower socioeconomic status (SES), older age at transplant (p<0.005, 95% CI: −5.5 to −.99, Student's t‐test) and episodes of late acute rejection (p<.001). Non‐adherence was also significantly associated with re‐transplantation and death secondary to chronic rejection by the Fisher exact test (p<0.006 and p<0.05, respectively). Non‐adherence to immunosuppressive therapy is a prevalent problem that is correlated with certain demographic and medical condition‐related risk factors and more frequent adverse consequences in the adolescent liver transplant population. The greater incidence of late acute rejection, death and re‐transplantation owing to chronic rejection in non‐adherent patients suggests that non‐adherence is significantly associated with an increased risk of morbidity and mortality. Further investigation to identify patients at greatest risk for non‐adherence is necessary to design the most effective intervention to increase patient survival and well being.
Successful transplantation in a child with rapid progression of autosomal recessive polycystic kidney disease associated with a novel mutation
Authors: Prelog Martina , Bergmann Carsten , Ausserlechner Michael J. , Fischer Helmut , Margreiter Raimund , Gassner Ingmar , Brunner Andrea , Jungraithmayr Therese C. , Zerres Klaus , Sergi E. Consolato , Zimmerhackl Lothar Bernd
Published: February 2006

Abstract: Autosomal recessive polycystic kidney disease (ARPKD) is the most common pediatric renal cystic disease with liver involvement. The vast majority of patients with ARPKD carry mutations in the recently characterized PKHD1 gene on chromosome 6p12. A Turkish female demonstrated rapid growth of both kidneys after delivery. Accelerated growth of both kidneys and increasing respiratory distress necessitated right‐sided nephrectomy at the age of three months. Because of persistent dyspnea and ongoing growth of the remaining kidney, the second kidney also had to be removed one month later. Biopsies taken from the kidney and the liver confirmed the diagnosis of ARPKD histologically. Renal ultrasound of the patient's consanguineous parents and her older brother showed normal results. PKHD1 mutation analysis yielded a novel homozygous missense mutation (c.1116C >G, F372L) in exon 14, coding for an Ig‐like domain (TIG), possibly involved in the increased growth of the kidneys. Peritoneal dialysis was performed for 12 months. The patient had successful transplantation at the age of 15 months and is doing well with actual immunosuppression with cyclosporine, mycophenolate mofetil, and prednisolone. In conclusion, the present case clearly demonstrates the favorable outcome of a child with severe ARPKD after bilateral nephrectomy, pre‐emptive dialysis, and successful transplantation.
Outcome after kidney transplantation in children with thrombotic risk factors
Authors: Kranz Birgitta , Vester Udo , Nadalin Silvio , Paul Andreas , Broelsch Christoph E. , Hoyer Peter F.
Published: February 2006

Abstract:  Background:  According to the data from the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS), vascular thrombosis accounts for 11.6% of graft losses in pediatric renal transplantation. In adults, inherited and acquired thrombophilic risk factors, e.g. factor V Leiden mutation, have been associated with early graft loss and increased rejection episodes. Data on the impact of these factors on the outcome of children after renal transplantation are rare.

Methods/patients:  Sixty‐six pediatric patients awaiting renal transplantation (mean age 10.1 yr) were screened for inherited and acquired risk factors for hypercoagulable disorders (protein C, S, and antithrombin III deficiency, antiphospholipid antibodies, factor V Leiden, prothrombin, and MTHFR mutation) in order to intensify anticoagulation in those with an increased risk for thrombophilia: intravenous heparin was administered with a partial prothrombin time (PTT) prolongation of 50 s for 14 days and switched to low‐molecular‐weight heparin for another 8 wk before aspirin was introduced for the first year. Patients without hypercoagulable risk factors were treated with heparin without PTT prolongation for 14 days and switched to aspirin immediately afterwards.

The results on graft survival, incidence of acute rejection episodes, and long‐term renal graft function were analyzed between recipients with and without hypercoagulable risk factors.

Results:  Thrombophilic risk factors were identified in 27.3% of our patients. No thrombosis occurred. One serious bleeding complication led to a second surgical intervention. The rate of acute rejection episodes was not increased in patients with and without thrombotic risk factors after 90 days (16.7 vs. 25%), 1 yr (22.2 vs. 33.3%), and 3 yr (38.9 vs. 41.7%) of follow‐up, respectively (p = n.s.). After a mean follow‐up of 3 yr the kidney function was comparable in both groups, with 63.1 in recipients with and 69.8 mL/min/1.73 m2 in recipients without hypercoagulable risk (p = n.s.). At latest follow‐up, three graft losses were found not to be attributed to thrombotic risk factors.

Interpretation:  Children with thrombophilic risk factors were identified and treated with an intensified anticoagulation regimen after renal transplantation. An increased risk for graft failure, acute rejection episodes, or impaired renal function for pediatric renal transplant recipients with hypercoagulable status was not found.
Nitrogen source and water regime effects on durum wheat photosynthesis and stable carbon and nitrogen isotope composition
Authors: Lopes Marta S. , Araus José L.
Published: February 2006

Water stress and nitrogen (N) availability are the main constraints limiting yield in durum wheat (Triticum turgidum L. var. durum). This work investigates the combined effects of N source (ammonium–NH4+, nitrate–NO3– or a mixture of both–NH4+:NO3–) and water availability (well‐watered vs. moderate water stress) on photosynthesis and water‐use efficiency in durum wheat (cv. Korifla) flag leaves grown under controlled conditions, using gas exchange, chlorophyll fluorescence and stable carbon isotope composition (δ13C). Under well‐watered conditions, NH4+‐grown plants had lower net assimilation rates (A) than those grown with the other two N forms. This effect was mainly due to lower stomatal conductance (gs). Under moderate water stress, differences among N forms were not significant, because water regime (WR) had a stronger effect on gs and A than did N source. Consistent with lower gs, δ13C and transpiration efficiency (TE) were the highest in NH4+ leaves in both water treatments. These results indicate higher water‐use efficiency in plants fertilized with NH4+ due to stomatal limitation on photosynthesis. Moreover, leaf δ13C is an adequate trait to assess differences in photosynthetic activity and water‐use efficiency caused by different N sources. Further, the effect of these growing conditions on the nitrogen isotope composition (δ15N) of flag leaves and roots was examined. Water stress increased leaf δ15N in all N forms. In addition, leaf δ15N increased as root N decreased and as leaf δ13C became less negative. Regardless of WR, the leaf δ15N of NO3–‐grown plants was lowest. Based on stepwise and canonical discriminant analyses, we conclude that plant δ15N together with δ13C and other variables may reflect the conditions of N nutrition and water availability where the plants were grown. Thus well‐watered plants grown with NH4+:NO3– resembled those grown with NO3–, whereas under water stress they were closer to plants grown with NH4+.
Grapevine promoter directs gene expression in the nectaries of transgenic tobacco
Authors: Burger Anita L. , Watts Leonora , Botha Frederik C.
Published: February 2006

A major obstacle in the genetic manipulation of fruit ripening in grapevine (Vitis vinifera L.) remains the lack of regulatory elements (promoters) to regulate tissue‐ and ripening‐specific expression of the transgene in the grape berry. In this study, a cDNA previously shown to identify a fruit‐ and ripening‐specific proline‐rich protein from grapevine (mrip1) was used to isolate a fruit‐ and ripening‐specific promoter. Sequence analysis of the 5.5‐kb region directly upstream of the mrip1 transcription initiation site (TIS) revealed a 2.8‐kb AT‐rich region directly upstream of the mrip1 TIS and the presence of the coding and the 5′ untranscribed flanking region (UTR) of a proline‐rich protein further upstream. In silico analysis of the 2.8 kb directly upstream of the mrip1 TIS revealed several putative cis‐acting regulatory elements. These include a spectrum of hormone‐, light‐, phytochrome‐, sugar‐ and stress‐responsive elements. Based on the sugar‐responsive 2.2 kb upstream of the mrip1 TIS, a 2.2‐kb fragment of the mrip1 5′ UTR flanking region was selected for functional analysis of the promoter. Functionality of mrip1:sgfpS65T fusion gene was confirmed by transient expression in green pepper pericarp tissue, before introduction into tobacco by Agrobacterium‐mediated transformation. In transgenic tobacco, transcription of the mrip1:sgfpS65T fusion was developmentally regulated and specific to the ovary and nectary‐tissue specific of the developing flower. While low in immature flowers, green fluorescent protein (GFP) rapidly accumulated to the high level of expression visualized in the flower in full‐bloom, followed by a decrease in the final stages of ovary development. These observations suggest that the 2.2 kb mrip1 promoter is functional and that this promoter region harbours cis‐elements necessary for tissue‐ and developmental‐specific regulation of GFP expression. It furthermore suggests that the transcriptional activation of mrip1 is mediated by developmental signals present in both grapevine berries and tobacco flowers.
Effect of elevated CO2, temperature and drought on photosynthesis of nodulated alfalfa during a cutting regrowth cycle
Authors: Erice Gorka , Irigoyen Juan J. , Pérez Pilar , Martínez‐Carrasco Rafael , Sánchez‐Díaz Manuel
Published: February 2006

Rising atmospheric CO2 may increase potential net leaf photosynthesis under short‐term exposure, but this response decreases under long‐term exposure because plants acclimate to elevated CO2 concentrations through a process known as downregulation. One of the main factors that may influence this phenomenon is the balance between sources and sinks in the plant. The usual method of managing a forage legume like alfalfa requires the cutting of shoots and subsequent regrowth, which alters the source/sink ratio and thus photosynthetic behaviour. The aim of this study was to determine the effect of CO2 (ambient, around 350 vs. 700 µmol mol−1), temperature (ambient vs. ambient + 4° C) and water availability (well‐irrigated vs. partially irrigated) on photosynthetic behaviour in nodulated alfalfa before defoliation and after 1 month of regrowth. At the end of vegetative normal growth, plants grown under conditions of elevated CO2 showed photosynthetic acclimation with lower photosynthetic rates, Vcmax and ribulose‐1,5‐bisphosphate carboxylase/oxygenase (rubisco) activity. This decay was probably a consequence of a specific rubisco protein reduction and/or inactivation. In contrast, high CO2 during regrowth did not change net photosynthetic rates or yield differences in Vcmax or rubisco total activity. This absence of photosynthetic acclimation was directly associated with the new source‐sink status of the plants during regrowth. After cutting, the higher root/shoot ratio in plants and remaining respiration can function as a strong sink for photosynthates, avoiding leaf sugar accumulation, the negative feed‐back control of photosynthesis, and as a consequence, photosynthetic downregulation.
Genetic engineering approaches to enrich rice with iron and vitamin A
Authors: Lucca Paola , Poletti Susanna , Sautter Christof
Published: February 2006

Major staple crops are often deficient in some of the nutrients required in human diet. Thus, malnutrition is a major problem, especially in developing countries, where a diversified diet is not affordable for the majority. Several strategies have been adopted to improve nutrition. However, micronutrient deficiency is still widely spread. Rice is one of the most important staple foods for a large part of the world's population. Therefore, even a small improvement in nutritional content of rice seeds can have a dramatic impact on human health. Different approaches are being exploited to produce rice enhanced in nutrients with iron and provitamin A.
Response of antioxidant systems to NaCl stress in the halophyte Cakile maritima
Authors: Amor Nader Ben , Jiménez Ana , Megdiche Wided , Lundqvist Marianne , Sevilla Francisca , Abdelly Chedly
Published: February 2006

The effects of salt stress on antioxidative activities were investigated in a coastal halophyte, Cakile maritima. Two Tunisian accessions, Jerba and Tabarka, were compared. Plants were subjected to 100, 200, or 400 mM NaCl for 20 days. Parameters of oxidative stress [malondialdehyde (MDA), electrolyte leakage (EL), and hydrogen peroxide (H2O2) concentration], activities of several enzymes [superoxide dismutase (SOD), catalase (CAT), peroxydase (POD), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR)], and antioxidant molecules (ascorbate, ASC, and glutathione, GSH) were determined. Growth of Jerba plants was improved at 100 mM NaCl as compared to that of control. Tabarka growth was inhibited by salt at all NaCl concentrations. The relative salt tolerance of Jerba was associated with high antioxidant enzyme activities and glutathione content, together with low MDA content, EL, and H2O2 concentration. Lower antioxidant activities and higher MDA content, EL, and H2O2 concentration were found in Tabarka. As a whole, these data suggest that the capacity to limit oxidative damage is important for salt tolerance of C. maritima.
Enhanced tolerance to ozone and drought stresses in transgenic tobacco overexpressing dehydroascorbate reductase in cytosol
Authors: Eltayeb Amin Elsadig , Kawano Naoyoshi , Badawi Ghazi Hamid , Kaminaka Hironori , Sanekata Takeshi , Morishima Isao , Shibahara Toshiyuki , Inanaga Shinobu , Tanaka Kiyoshi
Published: February 2006

Ascorbate (vitamin C) is a potent antioxidant protecting plants against oxidative damage imposed by environmental stresses such as ozone and drought. Dehydroascorbate reductase (DHAR; EC 1.8.5.1) is one of the two important enzymes functioning in the regeneration of ascorbate (AsA). To examine the protective role of DHAR against oxidative stress, we developed transgenic tobacco plants overexpressing cytosolic DHAR gene from Arabidopsis thaliana. Incorporation of the transgene in the genome of tobacco plants was confirmed by polymerase chain reaction and Southern blot analysis, and its expression was confirmed by Northern and Western blot analyses. These transgenic plants exhibited 2.3–3.1 folds higher DHAR activity and 1.9–2.1 folds higher level of reduced AsA compared with non‐transformed control plants. The transgenic plants showed maintained redox status of AsA and exhibited an enhanced tolerance to ozone, drought, salt, and polyethylene glycol stresses in terms of higher net photosynthesis. In this study, we report for the first time that the elevation of AsA level by targeting DHAR overexpression in cytosol properly provides a significantly enhanced oxidative stress tolerance imposed by drought and salt.
Carotenoid biotechnology in plants for nutritionally improved foods
Authors: Botella‐Pavía Patricia , Rodríguez‐Concepción Manuel
Published: February 2006

Carotenoids participate in light harvesting and are essential for photoprotection in photosynthetic plant tissues. They also furnish non‐photosynthetic flowers and fruits with yellow to red colors to attract animals for pollination and dispersal of seeds. Although animals can not synthesize carotenoids de novo, carotenoid‐derived products such as retinoids (including vitamin A) are required as visual pigments and signaling molecules. Dietary carotenoids also provide health benefits based on their antioxidant properties. The main pathway for carotenoid biosynthesis in plants and microorganisms has been virtually elucidated in recent years, and some of the identified biosynthetic genes have been successfully used in metabolic engineering approaches to overproduce carotenoids of interest in plants. Alternative approaches that enhance the metabolic flux to carotenoids by upregulating the production of their isoprenoid precursors or interfere with light‐mediated regulation of carotenogenesis have been recently shown to result in increased carotenoid levels. Despite spectacular achievements in the metabolic engineering of plant carotenogenesis, much work is still ahead to better understand the regulation of carotenoid biosynthesis and accumulation in plant cells. New genetic and genomic approaches are now in progress to identify regulatory factors that might significantly contribute to improve the nutritional value of plant‐derived foods by increasing their carotenoid levels.