bluuebunny/crossref_metadata_2025 huggingface dataset:
A global ocean carbon climatology: Results from Global Data Analysis Project (GLODAP)
Authors: Key R. M. , Kozyr A. , Sabine C. L. , Lee K. , Wanninkhof R. , Bullister J. L. , Feely R. A. , Millero F. J. , Mordy C. , Peng T.‐H.
Published: December 2004

During the 1990s, ocean sampling expeditions were carried out as part of the World Ocean Circulation Experiment (WOCE), the Joint Global Ocean Flux Study (JGOFS), and the Ocean Atmosphere Carbon Exchange Study (OACES). Subsequently, a group of U.S. scientists synthesized the data into easily usable and readily available products. This collaboration is known as the Global Ocean Data Analysis Project (GLODAP). Results were merged into a common format data set, segregated by ocean. For comparison purposes, each ocean data set includes a small number of high‐quality historical cruises. The data were subjected to rigorous quality control procedures to eliminate systematic data measurement biases. The calibrated 1990s data were used to estimate anthropogenic CO2, potential alkalinity, CFC watermass ages, CFC partial pressure, bomb‐produced radiocarbon, and natural radiocarbon. These quantities were merged into the measured data files. The data were used to produce objectively gridded property maps at a 1° resolution on 33 depth surfaces chosen to match existing climatologies for temperature, salinity, oxygen, and nutrients. The mapped fields are interpreted as an annual mean distribution in spite of the inaccuracy in that assumption. Both the calibrated data and the gridded products are available from the Carbon Dioxide Information Analysis Center. Here we describe the important details of the data treatment and the mapping procedure, and present summary quantities and integrals for the various parameters.
Role of the atmosphere in seasonal phase locking of El Niño
Authors: Spencer Hilary
Published: December 2004

The variations with the seasonal cycle of the atmospheric response to constant SST anomalies in the eastern tropical Pacific are investigated with the atmospheric GCM, HadAM3. The equatorial wind response is weakest in January and February when the warmest SSTs are south of the Equator and strongest in April when the warmest SSTs are on the Equator. This may have consequences for the seasonality of the onset and termination of El Niño. Westerly wind anomalies in the tropical Pacific associated with El Niño have previously been observed to shift south of the Equator, weakening on the Equator, during the northern winter. It has been suggested that this may contribute to the termination of El Niño in spring. These experiments demonstrate that such a shift can arise solely in response to the mean seasonal cycle during El Niño and does not require changes in SST anomalies.
Immune deviation and the hygiene hypothesis: A review of the epidemiological evidence
Authors: Kemp Andrew , Björkstén Bengt
Published: December 2004

The epidemiological evidence for the proposal that early life immune deviation is the principal mechanism by which microbial agents prevent the development of atopy has been reviewed. Seven criteria are proposed which should ideally be fulfilled. The majority of studies only fulfill two or three criteria. For mycobacteria, measles and respiratory viruses there are studies that demonstrate a significant increase in atopy or allergic disease. Parasite infections, which provide a strong TH2 stimulus, are associated with reduced rather than enhanced allergen sensitization. The available epidemiological evidence does not provide support for a mechanism of early life immune deviation. The principal environmental influences on atopic disease are likely to occur throughout life and involve interactions between microbes and other non‐infective and lifestyle factors.
Different sensitization profile for asthma, rhinitis, and eczema among 7‐8‐year‐old children: Report from the Obstructive Lung Disease in Northern Sweden studies
Authors: Rönmark Eva , Perzanowski Matthew , Platts‐Mills Thomas , Lundbäck Bo
Published: December 2004

Sensitization to different airborne allergens in relation to asthma, rhinitis, and eczema has been studied. A cross‐sectional study was performed among 7–8‐year‐old children living in northern Sweden. The ISAAC‐questionnaire with additional questions were sent to the parents, and 3431 (97%) participated. Two‐thirds of the children were invited to undergo a skin test with 10 common airborne allergens, and 2148 (88%) participated. The prevalence rates of all three diseases were significantly higher among the children who were sensitized to any of the tested allergens. Among asthmatics, 40% were sensitized to cat, 34% to dog, 28% to horse, 23% to birch and 16% to timothy. The corresponding figures for rhinitis were: cat 49%, dog 33%, horse 37%, birch 46%, timothy 32%; and for eczema: cat 29%, dog 21%, horse 15%, birch 20%, and timothy 11%. Only a few children were sensitized to mites or moulds. The main risk factors for all three diseases were type‐1 allergy and a family history of the disease. Independently from other risk factors, sensitization to dog (OR 2.4) and horse (OR 2.2) were significant risk factors for asthma. Sensitization to birch (OR 6.0), horse (OR 4.1), and timothy (OR 2.8) were significant risk factors for rhinitis, while birch (OR 2.4), dog (OR 2.0) and cat (OR 1.6) were significant risk factors for eczema. Despite a large over‐lapping of the diseases the pattern of sensitization was different for asthma, rhinitis and eczema. Sensitization to cat was most common among all children, but sensitization to dog and horse was associated with the highest risk for asthma, and sensitization to birch showed the highest risk for rhinitis and eczema. The different risk factor pattern for the often coexisting diseases; asthma, rhinitis, and eczema, may indicate differences in the etiology.
ISAAC‐based asthma and atopic symptoms among Ha Noi school children
Authors: Nga Nguyen Ngoc , Chai Sanders K. , Bihn Ta Tuyet , Redding Gregory , Takaro Tim , Checkoway Harvey , Son Phan Han , Van Duong Khanh , Keifer Matthew , Trung Le Van , Barnhart Scott
Published: December 2004

Childhood asthma and atopy prevalence patterns in the developing world are only beginning to be defined. No such information exists for Vietnam. Estimates would assist in anticipating health service needs as well as add to the growing database on global patterns of atopy. To estimate the prevalence of atopic symptoms in school children in Ha Noi, Vietnam, a cross‐sectional survey was conducted of children aged 5‐ to 11‐years‐old in two schools using the parent self‐administered International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. The response rate was 66.4% (969 responses). The overall prevalence of selected symptoms were: ‘ever wheezed’ 24.9%, ‘wheezed in past 12 months’ 14.9%, ‘ever had asthma’ 12.1%, ‘doctor‐diagnosed asthma’ 13.9%, ‘ever experienced allergic rhinitis (AR) symptoms’ 34.9%, ‘AR‐conjunctivitis symptoms in past 12 months’ 10.7%, ‘ever had hay fever’ 7.8%, ‘doctor‐diagnosed hay fever’ 11.2%, ‘ever had eczema’ 3.3% and ‘doctor‐diagnosed eczema’ 3.2%. Kappa statistics demonstrated high within symptom category consistency for ‘ever had asthma/doctor‐diagnosed asthma’ (0.728) and ‘ever had eczema/doctor‐diagnosed eczema’ (0.906). Age and gender adjusted odds ratios (OR) were also consistently significant across wheeze and allergic rhinitis symptom categories [highest OR = 10.10 (95% CI 6.23–16.35) between allergic rhinoconjunctivitis and wheeze in past 12 months]. There is a high prevalence of ISAAC‐based symptoms in school children in Ha Noi, Vietnam, often above global averages. The high level of association between atopic symptoms suggests some degree of reliability and validity. Childhood atopy symptom prevalence in Vietnam is more similar to that in developed countries rather than developing countries.
Adenoidectomy during early life and the risk of asthma
Authors: Mattila Petri S. , Hammarén‐Malmi Sari , Tarkkanen Jussi , Saxen Harri , Pitkäniemi Janne , Karvonen Marjatta , Tuomilehto Jaakko
Published: December 2004

The objective of the study was to evaluate the risk of asthma in children who had undergone an adenoidectomy, an operation frequently performed on children with glue ear or recurrent otitis media. Two surveys were carried out, a nation‐wide questionnaire returned by 483 individuals (survey A) and a survey of hospital discharge records involving 1616 children who had undergone an adenoidectomy and 161 control children who had undergone probing of the nasolacrimal duct due to congenital obstruction (survey B). The questionnaire (survey A) showed that an adenoidectomy before the age of 4 years was associated with asthma (OR 3.19, 95% CI 1.25; 8.13) and with allergy to animal dust (OR 2.50, 95% CI 1.27; 4.95). In survey B, asthma diagnosis was retrieved from the national asthma register. It showed also that adenoidectomy at an early age was associated with an increased risk of asthma (OR 6.74, 95% CI 2.99; 15.2). There was an association between asthma and adenoidectomy, even before adenoidectomy had actually been performed. The risk of asthma was highest among children who had had adenoidectomy because of recurrent otitis media. The observed association between an adenoidectomy and asthma may be explained by an underlying factor predisposing to both recurrent otitis media and asthma.
Management of an anaphylactoid reaction to methotrexate with a stepwise graded challenge
Authors: MacGinnitie Andrew J. , Walensky Loren D. , Turvey Stuart E. , Orange Jordan S. , Bonilla Francisco A. , Silverman Lewis B. , Oettgen Hans
Published: December 2004

We report the management of a 15‐year‐old boy with an anaphylactic or anaphylactoid response to his first dose of methotrexate during induction therapy for acute lymphoblastic leukemia (ALL). Because weekly methotrexate therapy is an important component of continuation chemotherapy for pediatric ALL, a stepwise graded challenge was employed to achieve drug tolerance.
Reduced IL‐2‐induced IL‐12 responsiveness in atopic children
Authors: Aniansson Zdolsek Helena , Janefjord Camilla K. , Fälth‐Magnusson Karin , Jenmalm Maria C.
Published: December 2004

Atopy may be associated with a reduced T‐cell function particularly regarding maturation of T helper 1 (Th1) responses. We hypothesized that atopic children may have a reduced capacity to up‐regulate the β2 subunit of the interleukin‐12 (IL‐12) receptor (IL‐12Rβ2, the signal‐transducing component). The study included 38 children followed from birth to the age of 7 years. Twenty one had a cumulative history of atopic disease, whereas 17 had none. Sixteen out of 21 children also had atopic symptoms within the past year (current), out of whom 10 children had atopic airway symptoms. The expression of IL‐12Rβ2 mRNA was analyzed by quantitative real‐time PCR and the secretion of interferon‐γ (IFN‐γ), IL‐5 and IL‐10 was assessed by enzyme‐linked immunosorbent assay (ELISA). Children with current atopic airway symptoms and high levels of total IgE up‐regulated IL‐12Rβ2 mRNA expression less than non‐atopic children with low IgE levels after IL‐2 stimulation. This was accompanied by a low IL‐2‐ and IL‐12‐induced IFN‐γ production, possibly reflecting the reduced capacity of atopic children to up‐regulate the IL‐12 receptor. As IL‐2 is needed to initiate and sustain immune responses and IL‐12 promotes Th1 responses, this may contribute to the Th2‐skewed pattern in atopic children.
The costs of atopy and asthma in children: Assessment of direct costs and their determinants in a birth cohort
Authors: Weinmann Stefan , Kamtsiuris Panagiotis , Henke Klaus‐Dirk , Wickman Magnus , Jenner Asa , Wahn Ulrich
Published: December 2004

The aim of this study was to estimate costs accrued by the health care of children with asthma in comparison to children with atopic eczema and seasonal rhinitis and to investigate cost determinants. From the multicenter cohort study (MAS‐90), we selected children with an asthma, atopic eczema and/or seasonal rhinitis diagnosis during the first 8 years of life, and overall 8‐year health care utilization was estimated retrospectively by reviewing medical records. Asthma treatment (n = 76) incurs an average cost of US$ 627 per year, 44% due to hospital stays. Atopic eczema treatment (n = 91) cost on average US$ 219 and seasonal rhinitis (n = 69) US$ 57 per year. In asthma and atopic eczema, costs increase significantly with disease severity. Allergy diagnostics use accounts for only 1% of total costs. Costs for asthma and atopic eczema treatment are highest in those years when topical steroids are used for the first time, but decrease with every further year of steroid use. A remarkable 25% of asthmatic children with severe symptoms were not treated according to national guidelines, so that most steroid treatment was initiated during the first hospital stay. In the case of asthma, total direct costs increased until the 3rd year of the disease, and then decreased with further years of diagnosis, while steroid use continued to increase. These results indicate a ‘learning effect’ in the treatment of asthma and atopic eczema for each patient as well as considerable cost‐saving potential by preventing severe asthma. Moreover, the importance of considering cost‐driving factors and using cohort or longitudinal designs in cost‐of‐illness approaches is emphasized.
Steroid‐sensitive indices of airway inflammation in children with seasonal allergic rhinitis
Authors: Meyer Peter , Andersson Morgan , Persson Carl G. A. , Greiff Lennart
Published: December 2004

Previous studies involving adults have demonstrated that airway glucocorticosteroids inhibit plasma exudation and eosinophil activity in allergic rhinitis. This study explores the possibility that plasma exudation, exudative responsiveness, and the occurrence of eosinophil activity‐related proteins are glucocorticosteroid‐sensitive nasal mucosal indices in allergic children. Using a placebo‐controlled, parallel‐group design effects of nasal budesonide (64 µg per nasal cavity b.i.d) were determined in children with seasonal allergic rhinitis. Nasal lavage fluid levels of eotaxin, eosinophil cationic protein (ECP), and α2‐macroglobulin, indicating plasma exudation, were determined, the latter with and without challenge with topical histamine. Nasal lavage fluid levels of α2‐macroglobulin and ECP increased significantly during the pollen season, and the acute plasma exudation response to histamine was significantly greater during than outside the season. There was a trend towards a seasonal increase in nasal lavage fluid levels of eotaxin. Budesonide significantly inhibited the seasonal increase in α2‐macroglobulin as well as the exudative hyperresponsiveness to histamine. Any tendency of increases in mucosal output of eotaxin and ECP was abolished by the glucocorticosteroid treatment. We conclude that mucosal exudation of plasma, as a global sign of active inflammatory processes, is a glucocorticosteroid‐sensitive facet of allergic rhinitis in children. Exudative hyperresponsiveness, potentially caused by several weeks of mucosal inflammation, emerges as a significant feature of allergic rhinitis in children, and its development is prevented by local treatment with a glucocorticosteroid drug. The seasonal increase in ECP and the trend for an increase in eotaxin were absent in the glucocorticosteroid‐treated subjects.
Effect of oral cyclosporin A in children with Staphylococcus aureus‐colonized vs. S. aureus‐infected severe atopic dermatitis
Authors: Bunikowski Rita , Mielke Martin , Bräutigam Matthias , Renz Harald , Wahn Ulrich
Published: December 2004

Atopic dermatitis (AD) is frequently associated with skin colonization or infection with Staphylococcus aureus strains producing exotoxins. The aim of this investigation was to evaluate the effect of oral cyclosporin A (CsA) on disease severity and bacterial counts in colonized and infected patients. Eleven children with severe AD (SCORAD index >50, mean objective SCORAD score >40) were treated for 8 weeks with 2.5–5 mg/kg CsA. In five patients, the skin was only colonized with S. aureus whereas the remaining six patients presented clinically relevant suppurative S. aureus skin infections characterized by small pustules, crustings, pus and increased pruritus in the presence of S. aureus as determined by contact sampling and culture which regularly resulted in the indication for antibiotic treatment. Clinical and microbiological investigations were performed before and after CsA therapy. Clinical signs and symptoms of AD improved in all patients with a reduction in mean SCORAD index from 74 to 29 (p < 0.001). However, disease severity and bacterial counts were more reduced by CsA in the colonized patients compared with the patients with clinical overt infections. In conclusion, treatment with CsA resulted in an improvement of clinical symptoms in children suffering from severe AD. However, anti‐infective treatment administered before immunomodulatory therapy is likely to be decisive for the long‐term therapeutic effect.
Effects of breast milk from allergic and non‐allergic mothers on mitogen‐ and allergen‐induced cytokine production
Authors: Böttcher Malin F. , Fredriksson Jenny , Hellquist Anna , Jenmalm Maria C.
Published: December 2004

Breast milk contains several components that provide specific immunity and affect the maturation of the infant's immune system. The aim of this study was to analyze the effects of breast milk, on mitogen‐ and allergen‐induced cytokine production from cord blood mononuclear cells (CBMC), and if those effects differ between allergic and non‐allergic mothers. The cells were incubated for 96 h with phytohemagglutinin (PHA), ovalbumin or cat dander in the presence of various dilutions of colostrum. Colostrum inhibited both mitogen‐ and cat‐induced IFN‐γ and mitogen‐induced interleukin‐4 (IL‐4) production. The inhibition on IFN‐γ production was to some extent caused by TGF‐β, as the effect was modified when an anti‐TGF‐β antibody was added to the cultures. In contrast, colostrum enhanced allergen‐induced production of the Th2‐like cytokines IL‐5 and IL‐13, and this was accompanied with increased production of IL‐10. No differences were found between allergic and non‐allergic mothers. The inhibitory effect of breast milk on IFN‐γ production, which was partly due to the high levels of TGF‐β, together with the enhancing effect on IL‐10 secretion, confirm that breast milk is anti‐inflammatory. Although the production of IL‐5 and IL‐13 was enhanced by colostrum, this was accompanied with an increased production of IL‐10. Together with the high levels of TGF‐β in breast milk and inhibitory effect of colostrum on IL‐4 production, this suggests a possible mechanism whereby breast‐feeding may protect against the development of allergy. Despite differences in the composition of breast milk between allergic and non‐allergic mothers, the effects of breast milk on cytokine production from CBMC were independent of the atopic status of the mothers.
Renin angiotensin system gene polymorphisms in pediatric renal transplant recipients
Authors: Filler Guido , Yang Fang , Martin Anja , Stolpe Joachim , Neumayer Hans‐Helmut , Hocher Berthold
Published: December 2004

Abstract: Genetic variability in the renin angiotensin system may modify renal responses to injury and disease progression. We therefore examined whether the insertion/deletion polymorphism of the angiotensin‐converting enzyme (ACE) gene, the Met235→Thr polymorphism of the angiotensinogen (AGT) gene, and the A1166→C polymorphism of the angiotensin II type 1 receptor gene (ATR1) were associated with disease progression and outcome after renal transplantation (Tx) in 100 Caucasian pediatric renal transplant recipients. The observed allele frequencies were: DD 31%, DI 41% and II 28%, for ACE; MM 42%, MT 37% and TT 21%, for the methionine (Met)235→threonine (Thr) polymorphism of AGT; and AA 51%, AC 38% and CC 11%, for the adenine (A)1166→cytosine (C) gene polymorphism. The slope of 1/creatinine was determined by linear regression analysis of a median of 12 points before and after renal Tx, and the population was divided in two equal groups, according to the slope, both before and after Tx. There were no statistically significant differences for AGT, ACE, and ATR1 polymorphisms with regard to the slope of 1/creatinine before renal Tx. After renal Tx, the ACE II genotype (p=0.024, chi‐square test) and the presence of the I allele (p=0.033, chi‐square test) were associated with a favorable slope of 1/creatinine. There was no association of the AGT or the ATR1 polymorphism with outcome after renal Tx, and none of the genotypes were associated with hypertension before or after renal Tx. We suggest that the beneficial association of disease progression after renal Tx with the II genotype and/or the presence of the I allele in our pediatric cohort might be explained by a lower activity of the circulating ACE enzyme associated with the I allele.
Short‐term pediatric renal transplant survival: Blood pressure and allograft function
Authors: Mitsnefes Mark M. , Omoloja Abiodun , McEnery Paul T.
Published: December 2004

Abstract: Hypertension is prevalent after renal transplantation (Tx) and associated with graft failure in children and adults. However, the effect of blood pressure (BP) on short‐term renal allograft function is uncertain. We assessed the associations among BP pretransplant, and 3 months and 1 yr post‐transplant, and 1‐yr post‐transplant measured glomerular filtration rate (mGFR) in 61 children with a functioning graft. The GFR was determined using a single intravenous (i.v.) injection of Optiray 350®. Data were collected between January 1994 and January 2000. The mean mGFR 1 yr after renal transplant was 63.6 ± 19.9 mL/min/1.73 m2 in 26 live donor recipients and 50.8 ± 23.3 mL/min/1.73 m2 in 35 cadaveric donors (p = 0.029). Correlation analysis showed significant negative associations of 1‐yr mGFR with systolic blood pressure (SBP) and diastolic blood pressure (DBP) 3 months after renal Tx (r = − 0.58, p < 0.0001 and r = − 0.50, p < 0.0001, respectively), and with SBP (r = − 0.37, p = 0.003) and DBP (r = − 0.32, p = 0.01) 1 yr after renal Tx. Multi‐variate regression analysis showed that the SBP 3 months after Tx (p < 0.001), number of acute rejections (p = 0.002), donor age (p = 0.02), and cold ischemia time (p = 0.03) were independent predictors for the 1‐yr mGFR. These results indicate that a higher SBP in the first few months post‐renal Tx is associated with decreased renal allograft function in children 1 yr post‐Tx.
Treatment of monomorphic B‐cell lymphoma with rituximab after liver transplantation in a child
Authors: Bueno Javier , Ramil Carmen , Somoza Ivan , Sanchez‐Galindo Amelia , Solar Alfonso , Arnal Francisco , Alvarez Augusto , Sánchez‐Mozo Pilar , Gómez Manuel
Published: December 2004

Abstract:Rituximab, a monoclonal antibody directed against the B‐cell specific CD20 antigen has been used with success in post‐transplant lymphoproliferative disorder (PTLD) of B‐cell phenotype. However, the use of such drug in children with liver transplantation and PTLD is very limited. We report a 2‐yr‐old liver transplant recipient with monomorphic non‐Hodgkin lymphoma of B‐cell origin. The lymphoma did not respond to immunosuppression withdrawal, with a subsequent allograft rejection. Despite resumption of immunosuppression and rejection treatment, the lymphoma was successfully treated with rituximab.
Predictive value of pretransplantation cyclosporine pharmacokinetic studies on initial post‐transplantation dosing in pediatric kidney allograft recipients
Authors: Seikku Paula , Hoppu Kalle , Jalanko Hannu , Holmberg Christer
Published: December 2004

Abstract:Despite the introduction of a variety of new immunosuppressive agents, cyclosporine A (CsA) has maintained a strong position in pediatric transplantation (Tx). Post‐Tx dosing with CsA is a challenging task because of the narrow therapeutic window of the drug, the great individual variability of metabolism and the lack of consensus about the optimal dosage and targeted blood concentration. Sufficient administration of CsA may be protective against acute rejections and other early complications after Tx, which is crucial for the long‐term survival of the graft. Individual doses based on pre‐Tx pharmacokinetic studies might be helpful in achieving optimal early concentrations of CsA. To asses the usefulness of pharmacokinetic studies, we retrospectively compared the post‐Tx doses administered with the individually predicted doses between 1988 and 1998. Multiple regression of data on 65de novorenal transplant recipients, 1.1–15.5 yr old, was used to analyze the significance of the predicted dose, trough blood concentration of CsA (B‐CsA), serum creatinine and age at the time of Tx in explaining the doses used during the first three post‐Tx weeks. Patients were grouped according to age (<2, 2–8 and >8 yr), according to the predicted dose (within or outside ±25% of age‐group average), and according to the oral formulation of CsA. Standard dosing scheme was simulated by using age‐specific average doses in the place of the individual predicted doses. Administered doses of CsA were high [averaging 22.6 (504), 20.7 (484), and 12.4 mg/kg/d (329 mg/m2/d) for patients <2, 2–8, and >8 yr old] but the average B‐CsA remained in the target range of 250–450 μg/L. The predicted dose and age were significant parameters in explaining the administered doses during the first 3 wk after Tx. B‐CsA and S‐creatinine were non‐significant. The predicted doses were used to initiate the dosing of CsA after Tx (R2 = 0.70) and adjustments to dosing were made during the next weeks (R2 = 0.59, 0.52). Multiple regression model showed better fit for 60% of our patients, who had atypical predicted doses (R2 = 0.74, 0.60, 0.64 for first, second and third post‐Tx weeks, respectively), most remarkably in patients <2 yr of age, than for the study population as a whole. A simulated standard dose was not able to explain the administered doses of CsA. In conclusion, pre‐Tx pharmacokinetic studies are valuable for determining individual post‐Tx starting doses, especially for those patients who need high or low doses of CsA. Individual dosing led to relatively high initial CsA doses, which could be significant for the long‐term survival of the graft.
Prevalence and clinical significance of human herpesviruses 6 and 7 active infection in pediatric liver transplant patients
Authors: Feldstein Ariel E. , Razonable Raymund R. , Boyce Thomas G. , Freese Deborah K. , El‐Youssef Mounif , Perrault Jean , Paya Carlos V. , Ishitani Michael B.
Published: December 2004

Abstract:  Recent studies in adult liver transplant patients have suggested that both human herpesvirus (HHV)‐6 and HHV‐7 infection are important causes of morbidity following liver transplantation. However, the impact of HHV‐6 and ‐7 infection in pediatric liver transplant patients remains largely unknown. The aims were to determine the prevalence of HHV‐6 and ‐7 infection in pediatric liver transplant patients and to determine whether there is an association between HHV‐6 and ‐7 infection with episodes of graft rejection and cytomegalovirus (CMV) infection. A total of 46 pediatric liver transplant patients transplanted at Mayo Clinic between January 1994 and January 2000 were evaluated. Quantitative polymerase chain reaction (PCR) assays for CMV, HHV‐6 and HHV‐7 were performed on stored sera obtained prior to transplant, weekly for 8 wk and at 4 months and 1 yr post‐transplant. Pretransplant sera were tested for HHV‐6 antibodies by indirect immunofluorescence assay. A total of 215 blood samples were tested (mean 6.5 ± 3.1, range 3–18). CMV infection occurred in 11 of 33 (33.3%) patients, while CMV disease occurred in 4 of 33 (12%) patients. Infection with HHV‐6 (variant B) was detected in three of 33 (9.1%) patients. HHV‐7 infection was not detected. Case 1 and 2 were infants (10‐ and 11‐month old, respectively). Both were seronegative for HHV‐6 pretransplant. In both cases, HHV‐6 infection was associated with concurrent episodes of moderate to severe acute graft rejection. Case 3 was a 16‐yr‐old girl who was seropositive for HHV‐6 pretransplant. No clinical events were recorded and a liver biopsy performed per protocol showed no evidence of rejection. None of the three patients had concomitant CMV infection or disease. In this study, HHV‐6 infection occurred in 9% of pediatric liver transplant patients while HHV‐7 was not detected. A potential association between primary HHV‐6 infection and allograft rejection warrants further investigation.
Mycophenolate mofetil without antibody induction in cadaver vs. living donor pediatric renal transplantation
Authors: Ojogho O. , Sahney S. , Cutler D. , Baron P. W. , Abdelhalim F. M. , Hasan S. M. , Concepcion W.
Published: December 2004

Abstract: Mycophenolate mofetil (MMF) is a new immunosuppressive agent that blocks de novo purine synthesis in T and B lymphocytes via a potent selective inhibition of inosine monophosphate dehydrogenase. MMF has been shown to significantly reduce the incidence of acute rejection in both adult and pediatric renal transplantation. The impact of MMF on routine antibody induction therapy in pediatric renal transplantation has not been defined. Remarkably, a recent North American Pediatric Transplant Cooperative Study concluded that T‐cell antibody induction therapy was deleterious for patients who received MMF. Our study examines the use of MMF in an evolving immunosuppressive strategy to avoid antibody induction in both living (LD) and cadaver (CAD) donor pediatric renal transplantation.

We retrospectively analyzed the records of 43 pediatric renal transplants that received MMF‐based triple therapy without antibody induction therapy between November 1996 and April 2000. We compared CAD (n = 17) with LD (n = 26). The two groups were similar demographically except that CAD had significantly younger donors than LD, 26.1 ± 13.7 vs. 36.2 ± 9.2 yr (p = 0.006). All the patients received MMF at 600 mg/m2/b.i.d. (maximum dose of 2 g/d) and prednisone with cyclosporine (86%) or tacrolimus (14%). Mean follow‐up was >36 months for each group. Acute rejection rate at 6 months was 11.8% (CAD) vs. 15.4% (LD) (p = 0.999) and at 1 yr was 23.5% (CAD) vs. 26.9% (LD) (p = 0.999). Mean estimated glomerular filtration rate (ml/min/1.73 m2) at 6 months was 73.3 ± 15.3 (CAD) vs. 87.6 ± 24.2 (LD) (p = 0.068). Patient survival at 1, 2, and 3 yr was 100, 100, and 100% for CAD vs. 100, 96, and 96% for LD, respectively. Graft survival at 1, 2, and 3 yr was 100, 100, and 94% for CAD vs. 96, 88, and 71% for LD, respectively. Graft loss in CAD was because of chronic rejection (n = 2) while in LD it was because of non‐compliance (n = 6), post‐transplant lymphoproliferative disorder (n = 1), and sepsis (n = 1). In conclusion, MMF without antibody induction in both CAD and LD pediatric renal transplantation provides statistically similar and effective prophylaxis against acute rejection at 6 months and 1 yr post‐transplant. The short‐term patient and graft survival rates are excellent, however, non‐compliance remains a serious challenge to long‐term graft survival. Additional controlled studies are needed to define the role of MMF without antibody induction therapy in pediatric renal transplantation.
Daily photosynthetic and C‐export patterns in winter wheat leaves during cold stress and acclimation
Authors: Leonardos Evangelos D. , Savitch Leonid V. , Huner Norman P. A. , Öquist Gunnar , Grodzinski Bernard
Published: December 2004

Diurnal patterns of whole‐plant and leaf gas exchange and 14C‐export of winter wheat acclimated at 20 and 5°C were determined. The 5°C‐acclimated plants had lower relative growth rates, smaller biomass and leaf area, but larger specific leaf weight than 20°C plants. Photosynthetic rates in 20°C and 5°C‐acclimated leaves were similar; however, daytime export from 5°C‐acclimated leaves was 45% lower. Photosynthesis and export remained steady in 20°C and 5°C‐acclimated leaves during the daytime. By comparison, photosynthesis in 5°C‐stressed leaves (20°C‐acclimated plants exposed to 5°C 12 h before and during measurements) declined from 70 to 50% of the 20°C‐acclimated leaves during the daytime, while export remained constant at 35% of the 20°C‐acclimated and 60% of the 5°C‐acclimated leaves. At high light and CO2, photosynthesis and export increased in both 20°C and 5°C‐acclimated leaves, but rates in 5°C‐stressed leaves remained unchanged. At all conditions daytime export was greater than nighttime export. Taken together, during cold acclimation photosynthesis was upregulated, whereas export was only partially increased. We suggest that this reflects a requirement of cold‐acclimated plants to both sustain an increased leaf metabolic demand while concomitantly supporting translocation of photoassimilates to overwintering sinks.
Phenols and antioxidative status of Raphanus sativus grown in copper excess
Authors: Sgherri Cristina , Cosi Elena , Navari‐Izzo Flavia
Published: December 2004

Raphanus sativus L. cv. Rimbo was grown for 10 days after emergence in hydroponic culture containing 0.12 (control), 5, 10 and 15 µM copper. The seeds were germinated in the presence of the copper solution. The Cu contents increased with the treatment in both shoots and roots, maintaining in the roots a value eight‐ to ten‐fold higher than in the shoots. With the treatment both shoots and roots underwent growth inhibition and an increase in the percentage of dry weight. Membrane damage and lipid peroxidation increased and glutathione was oxidized as the copper concentration increased, indicating an acceleration of oxidative processes. Control shoots had high contents of reduced glutathione and low contents of phytochelatin‐SH whereas roots showed an opposite pattern, suggesting an utilization of reduced glutathione for phytochelatin synthesis. In both parts phytochelatin‐SH content reached the maximum at 5 µM copper and then decreased, reaching at 15 µM copper the control value in the roots and a value five‐fold higher than the control value in the shoots. The main phenolic acids represented in R. sativus were chlorogenic, vanillic, caffeic, siringic, p‐coumaric and ferulic acids whereas the least represented were gallic, protocatechuic and p‐hydroxybenzoic acids. The phenolic acids as well as the total and reduced ascorbate contents increased with the intensification of copper treatment. Notwithstanding these changes, total ascorbate remained 35% higher in the shoots than in the roots. The reduced ascorbate was thus able to replenish reducing equivalents to phenoxyl radicals thus explaining the increase in the phenolic compounds.
Involvement of chlorophyllase in chlorophyll metabolism in olive varieties with high and low chlorophyll content
Authors: Roca María , Mínguez‐Mosquera María Isabel
Published: December 2004

Olive fruits of the Arbequina variety are differentiated from those of Hojiblanca and Picual by the differing presence of 132‐OH‐chlorophyllaand of dephytylated chlorophyll derivatives during the life cycle of the fruit. During the fruit growth stage, which coincides with chlorophyll synthesis, chlorophyllase (EC: 3.1.1.14) is present in the three varieties but only yields chlorophyllides in Arbequina. The presence of oxidized catabolites of chlorophyllain fruits of the Arbequina variety during this same period confirms the activity of oxidative enzyme systems. The low synthesis of chlorophylls in the fruits of the Arbequina variety is associated with the fact that, during the natural biosynthetic turnover, the catabolic pathway is more potentiated than the anabolic one. In the ripening phase, in the Hojiblanca and Picual fruits, chlorophyllase activity was measured but the absence of chlorophyllides showed that this enzyme remains latent and that oxidative enzymes are the ones taking part in the chlorophyll disappearance. In the Arbequina variety, both chlorophyllase and oxidative enzymes are responsible for the chlorophyll degradation.
Effect of controlled expression of the hetR gene on heterocyst formation in the filamentous cyanobacterium Anabaena sp. PCC 7120
Authors: El‐Shehawy Rehab M. , Kleiner Diethelm
Published: December 2004

hetR is a central regulatory gene inducing and possibly maintaining irreversible heterocyst differentiation in filamentous cyanobacteria. A plasmid was constructed which enabled IPTG‐mediated, controlled expression of hetR from a ptac promoter in Anabaena. When introduced into a heterocyst‐deficient hetR mutant, induction led to massive formation of heterocysts in a medium free of combined nitrogen. In nitrate‐containing cultures, induction elicited formation of only a few heterocysts, but led to nitrogen chlorosis in vegetative cells as evidenced from degradation of phycobiliproteins. Removal of the inducer IPTG caused chlorosis and death of the organisms in nitrate‐free medium, but no reversal of heterocyst formation. This indicates that constant synthesis of HetR is not the (sole) reason for irreversibility of heterocyst formation.
An ABA‐responsive bZIP protein, OsBZ8, mediates sugar repression of α‐amylase gene expression
Authors: Lee Yi‐Ching , Lu Chung‐An , Casaretto Jose , Yu Su‐May
Published: December 2004

Expression of some α‐amylase genes in cereals is suppressed by sugars and activated by sugar starvation. A 100‐bp sugar response sequence (SRS) identified in the promoter of a rice α‐amylase gene, αAmy3, contains three essential motifs: the GC box, the G box, and the TATCCA element. To study the mechanism of sugar regulation of αAmy3 transcription, an ABA‐responsive bZIP protein, OsBZ8, which binds specifically to the G box in αAmy3 SRS was characterized and function analysed. In sucrose‐starved rice suspension cells and embryos, decline in OsBZ8 mRNA levels coincided with the induction of αAmy3 mRNA accumulation. In vivo gain‐ and loss‐of‐function studies by transient expression assays in rice embryos revealed that OsBZ8 suppresses SRS activity through the G box and overrides the activity of an activator, OsMYBS1, which binds to the TATCCA element. Gel mobility shift assays revealed that OsBZ8 binds specifically to the G box in vitro. These studies suggest that OsBZ8 is a suppressor responsible for sugar repression of αAmy3 expression, and OsMYBS1 is responsible for sugar starvation induced expression of αAmy3.
Involvement of an acid phosphatase on cell wall regeneration of tobacco protoplasts
Authors: Sano Akiko , Kaida Rumi , Maki Hisae , Kaneko Takako S.
Published: December 2004

Tobacco protoplasts begin to regenerate their own cell walls, the major components of which are β‐glucans, soon after they are transferred into an adequate medium. During the cell wall regeneration the protoplasts secrete two isoforms of acid phosphatase (APase) in time‐dependent manner. We determined that one of the isoforms, the Brefeldin A (BFA) sensitive one, is the cell wall resident APase (WP‐II) by immunoblotting of the isoform with anti‐WP‐II antibody. We hypothesized that the WP‐II may participate in the deposition of β‐glucan microfibrils on the protoplast surface during cell wall regeneration. In order to examine this hypothesis, the protoplasts were cultivated in the cell wall regeneration medium containing the same amount of the BFA‐sensitive APase (230 µg protein) as is secreted by the observed number of protoplasts (1.4 × 105 protoplasts) per plate (30‐mm‐diameter) during a 3‐h cultivation after transfer to the cell wall regeneration medium. The addition of WP‐II to the cell wall regeneration medium stimulated the deposition of β‐glucan microfibrils on the surface of the protoplasts during cell wall regeneration. To determine the stimulative effect of the 60 kDa polypeptide of WP‐II, protoplasts were cultivated in the medium containing the amount of anti‐WP‐II IgG (230 µg protein) equivalent to the BFA‐sensitive APase. These results suggested that the 60 kDa polypeptide of WP‐II is the BFA‐sensitive APase which is responsible for the enhanced deposition of β‐glucan microfibrils on the surface of the protoplasts.
The impact of nitrogen supply on the potential response of a noxious, invasive weed, Canada thistle (Cirsium arvense) to recent increases in atmospheric carbon dioxide
Authors: Ziska Lewis H.
Published: December 2004

A recognized invasive weed, Canada thistle (Cirsium arvense L. Scop.) was grown at ambient and pre‐ambient concentrations of atmospheric carbon dioxide [CO2] (373 and 287 μmol mol−1, respectively) at three levels of supplemental nitrogen (N) (3, 6 and 14.5 mM) from seeding until flowering [77 days after sowing (DAS)]. The primary objective of the study was to determine if N supply limited the potential photosynthetic and growth response of this species to the increase in atmospheric [CO2] which occurred during the 20th century (i.e. approximately 290 to 370 μmol mol−1 CO2). Leaf photosynthesis increased both as a function of growth [CO2] and N supply during the first 46 DAS. Although by 46 DAS photosynthetic acclimation was observed relative to a common measurement CO2 concentration, there was no interaction with N supply. Both [CO2] and N increased biomass, relative growth rates and leaf area whereas root : shoot ratio was increased by CO2 and decreased by increasing N; however, N supply did not effect the relative response to [CO2] for any measured vegetative parameter up to 77 DAS. Due to the relative stimulation of shoot biomass, total above‐ground N increased at elevated [CO2] for all levels of supplemental N, but nitrogen use efficiency (NUE) did not differ as a function of [CO2]. Overall, these data suggest that any potential response to increased atmospheric [CO2] in recent decades for this noxious weedy species was probably not limited by nitrogen supply.
Cytokinin‐induced upregulation of cytokinin oxidase activity in tobacco includes changes in enzyme glycosylation and secretion
Authors: Motyka Václav , Vaňková Radomíra , Čapková Věra , Petrášek Jan , Kamínek Miroslav , Schmülling Thomas
Published: December 2004

Regulation of cytokinin oxidase (CKX) activity in relation to enzyme glycosylation and secretion was studied in wild‐type (WT) and transgenic conditionally isopentenyltransferase gene (ipt)‐expressing (IPT) tobacco (Nicotiana tabacum L. cv. Wisconsin 38) cell suspensions, calli and leaves. An increase in endogenous cytokinin content due to the tetracycline (Tc)‐induced derepression of the ipt gene transcription or surface application of N6‐benzylaminopurine (BA) resulted in significant enhancement of CKX activity in all these plant materials. As revealed by Concanavalin A‐Sepharose 4B chromatography the cytokinin‐induced enhancement of CKX activity was associated predominantly with the N‐glycoform of the enzyme (10‐ to 15‐fold increase) in calli and leaves. Application of BA to the culture media of WT and IPT cell suspensions and the derepression of the ipt by Tc substantially enhanced endogenous levels of isoprenoid cytokinins and CKX activity in both cells and the culture medium. Most CKX activity in control, BA‐ and Tc‐treated cells was associated with the non‐glycosylated form of the enzyme, whereas the majority of CKX activity in the culture media was due to the glycosylated form. The pH optimum of CKX in cells (pH 8.5) differed considerably from that in the culture medium (pH 6.0). No significant differences were found in apparent Km(iP) values of CKX between control, BA‐ and Tc‐treated IPT cells and media or between purified glycosylated and non‐glycosylated CKX. These results suggest that cytokinins induce changes in the proportions of glyco‐ and non‐glycoforms of the enzyme in multicellular calli and leaves, and influence its secretion to the cell exterior.
A supaeromaculata mutation affects heterochrony in pea
Authors: Taylor Scott A. , Murfet Ian C.
Published: December 2004

Mutations in Aero1 promote the silver flecking (aeromaculata) commonly seen on wild‐type pea (Pisum sativum L.) leaves, resulting in a phenotype known as supaeromaculata. We show here the MIII/122 line carries a supaeromaculata mutation allelic to the type aero allele (aero1‐1). MIII/122 (aero1‐10) and aero1‐1 were also found to attain an adult leaf form, flower and undergo apical arrest earlier than their wild‐type progenitor, cv. Virtus and cv. Torsdag, respectively. Principal component analyses indicated that in both cases these characteristics co‐segregated with the supaeromaculata phenotype. These results suggest that Aero1 is associated with the timing of plant development. Plants carrying an aero1 mutation become fully adult and reproductively competent sooner than their wild‐type counterparts, suggesting Aero1 is required to delay these aspects of plant development. Thus, Aero1 represents a previously unrecognized heterochronic gene in the garden pea.
Size‐dependent attack rate and handling capacity: inter‐cohort competition in a zooplanktivorous fish
Authors: Hjelm Joakim , Persson Lennart
Published: December 2004

Two size‐dependent processes, metabolic requirements and foraging capacity, heavily influence the competitive ability of organisms. We studied the size‐dependent competitive ability of roach (Rutilus rutilus) in a laboratory experiment to determine the attack rate of roach as a function of roach and zooplankton sizes. The estimated size‐dependent attack rates, size‐dependent metabolic demands and handling capacities were subsequently used to interpret the outcome of a competition experiment between two size classes of roach. Furthermore, size‐dependent attack rates were implemented in an optimal foraging model to predict consumption rates and zooplankton selection to reveal the mechanisms behind competition.  The attack rate first increased with roach size to a maximum around 160 mm to thereafter decrease. Based on this result, we predicted that, small (150 mm) roach had a double advantage in competition for zooplankton in the pond experiment due to their higher attack rate and their lower metabolism compared to large (230 mm) roach. As expected, small roach depressed total zooplankton biomass to a higher extent than large roach, included more zooplankton in their diet and consumed smaller zooplankton. Predicted smallest size class of zooplankton in the diet was close to the observed. Also as expected, large roach fed more on the benthic resource and depressed the benthic resource to a larger extent than small roach. Large roach affected large zooplankton to a higher extent during the first part of the experiment, which could be related to their overall higher handling capacity. The higher impact of large roach on large zooplankton during the first part of the experiment, in turn, resulted in a lower estimated mass intake of zooplankton by small roach in the mixed treatment compared to small roach only treatments. Both small and large roach had a lower growth rate in the mixed treatment compared to single size class treatments. We relate the lower growth rate of small roach in the mixed treatment to large roach's higher efficiency on benthic resources and on large zooplankton during the first part of the experiment. In correspondence with diet data, large roach preferred the shore area of the pond with more benthic invertebrates and were also found more often close to the bottom. Although our results are explainable by exploitative interactions, the fact that the presence of large roach affected the feeding position of small roach points to that social interactions were also involved. Overall, our study implies that a mechanistic understanding is crucial for the interpretation of competition experiments, especially in systems with size‐structured interactions.