bluuebunny/crossref_metadata_2025 huggingface dataset:
Sulfhemoglobin formation in human erythrocytes by cystalysin, an L‐cysteine desulfhydrase from Treponema denticola
Authors: Kurzban G. P. , Chu L. , Ebersole J. L. , Holt S. C.
Published: March 2003

Cystalysin, isolated from the oral pathogen Treponema denticola, is an
l‐cysteine desulfhydrase (producing pyruvate, ammonia and hydrogen sulfide from cysteine) that can modify hemoglobin and has hemolytic activity. Here, we show that enzymatic activity of recombinant cystalysin depends upon stochiometric pyridoxal phosphate. The enzyme was not functional as an
l‐alanine transaminase, and had a strong preference for
l‐cysteine over
d‐cysteine. Cystalysin preferred small α‐
l‐amino acids as substrates or inhibitors and was far more active towards
l‐cysteine than towards the other standard amino acids that undergo pyridoxal phosphate‐dependent β‐elimination reactions (serine, threonine, tryptophan and tyrosine). Cystalysin tolerated small modifications to the carboxylate of
l‐cysteine (i.e., the methyl and ethyl esters of
l‐cysteine were good substrates), but the smallest possible peptide with an N‐terminal cysteine,
l‐cysteinylglycine, was a very poor substrate. These results, combined with the implicit requirement for a free amine for pyridoxal phosphate‐dependent reactions, imply that cystalysin cannot catabolize cysteine residues located within peptides. Cystalysin has Michaelis‐Menten kinetics towards
l‐cysteine, and there was little or no inhibition by ammonia, H2S, pyruvate and acetate. Human erythrocytes incubated with H2S or with cystalysin and cysteine primarily accumulated sulfhemoglobin and methemoglobin, along with minor amounts of choleglobin and protein aggregates. Erythrocytes retained the ability to reduce methemoglobin in the presence of H2S. Cystalysin could not modify hemoglobin when β‐chloroalanine was the substrate, indicating an absolute requirement for H2S production. Cystalysin appears to be an unregulated
l‐cysteine catabolizing enzyme, with the resulting H2S production being essential to the atypical hemolytic activity.
The BAMSE Project: presentation of a prospective longitudinal birth cohort study
Authors: Wickman Magnus , Kull Inger , Pershagen Göran , Nordvall S. Lennart
Published: March 2003

The aims of this prospective and longitudinal project are to establish crucial risk factors for asthma and other allergic diseases in childhood, and to study factors of importance for prognosis at already established allergic disease. Socio‐economic factors, such as inequality in health, are also to be addressed. The project started in February 1994. To reach sufficient power, 4,000 children had to be included. In November 1996, this number was reached (4,093). Inclusion in the study was made at 3–4 months of age. At that time, and before induction of allergic disease/asthma of the child, a questionnaire focused on exposure, genetics and socio‐economic factors was answered. Settled dust was sampled for later analysis of furred animal and mite allergens. When the children were aged both 1 and 2 years, their parents were asked to fill in new questionnaires focusing on respiratory and allergic (skin, gastrointestinal) symptoms, but also key variables of exposure. Cases with asthma are identified and, for every case, two matched controls drawn. During the following winter, the homes of cases and controls were investigated and the temperature, indoor humidity, air change rate and NO2 measured. Two hundred cases (5%) were expected to be identified during the first 2 years of the children's lives. Some 479 homes have now been investigated and 97.7% of the original 4,093 children still remain in the cohort. The 2‐year symptom follow‐up ended in November 1998. The 4‐year follow‐up started on 1 September 1998 and was planned to be finished in June 2000. Questionnaires (allergic and respiratory symptoms, key variables of exposure at home and day care) are sent out to all 4,093 families. All children are invited for examination, lung function tests (PEF, flow‐volume, MVV and oxygen clearance) and physical performance. Blood is taken from all children (20 ml). Allergy screening is performed and specific IgE examined. Blood cells will be frozen to allow for later DNA extraction. In subsets (children with any allergic and/or respiratory manifestation and controls), markers of inflammation in blood and urine will be examined, as well as eosinophils in nasal smear. Interviews are carried out to assess the severity of asthma, type/periodicity of health care given, asthma medication and parental sick leave when appropriate. As a separate project, financed by the EU, outdoor pollution as risk factors for asthma and allergies are to be studied within the BAMSE cohort. A follow‐up of 8–9 years is underway.
Ventricular shunts and the prevalence of sensitization and clinically relevant allergy to latex in patients with spina bifida
Authors: Buck Dietke , Michael Theo , Wahn Ulrich , Niggemann Bodo
Published: March 2003

Patients with spina bifida represent the highest‐risk group for developing hypersensitivity to latex. Recognized risk factors for these patients are repeated surgery and an atopic disposition. Our aim was to study the influence of a ventricular shunt as an independent risk factor. One hundred and sixty‐one patients with spina bifida (median age 10 years) were investigated for the presence of a shunting device and the number, type and date of previous surgical interventions. Additionally, skin‐prick tests and provocation tests were performed in order to classify sensitized and symptomatic latex‐allergic individuals. Eighty‐eight patients (54.7%) were sensitized; 55 (34.2%) were provocation‐positive. Patients with a shunt system had undergone a significantly higher number of surgical procedures (p < 0.0001) and showed significantly higher levels of immunoglobulin E (IgE)‐antibodies to latex (p < 0.0001) than patients without a shunting device. The total number of operations correlated significantly with the level of IgE‐antibodies to latex in serum (p < 0.0001), whereas the number of shunt operations in patients with a ventricular shunt did not significantly correlate with the degree of sensitization. In conclusion, patients with spina bifida who have a ventricular shunt are at particularly high risk because they undergo a significantly higher number of operations than patients without a ventricular shunt. However, the ventricular shunt does not seem to be an independent risk factor. Furthermore, this study emphasizes that individuals at high risk, such as patients with spina bifida, should be handled latex‐free from the very beginning of life.
Determination of T‐cell subpopulations and intracellular cytokine production (interleukin‐2, interleukin‐4, and interferon‐γ) by cord blood T‐lymphocytes of neonates from atopic and non‐atopic parents
Authors: Hagendorens Margo M. , Van Bever Hugo P. , Schuerwegh Annemie J. , De Clerck Luc S. , Bridts Chris H. , Stevens Wim J.
Published: March 2003

This report describes the results of a prospective study on immunological markers in cord blood for the prediction of allergic diseases in children. First we evaluated methodological aspects of the flow cytometric technique on cord blood cytokine measurements. Subsequently, the T‐cell subsets and percentage of cytokine‐producing cord blood T‐helper (Th) and T‐suppressor/cytotoxic lymphocytes of neonates from atopic and non‐atopic parents were compared. A group of 33 healthy, full‐term newborn infants of whom 23/33 were at risk for atopy (i.e. having at least one parent with one or more atopic symptoms and positive specific immunoglobulin E [IgE] to at least one common inhalant allergen) was studied. A flow cytometric technique was used to analyze cord blood T‐cell subsets and to determine the percentage of interleukin (IL)‐2‐, IL‐4‐, and interferon‐γ (IFN‐γ)‐producing cord blood Th and T‐suppressor/cytotoxic lymphocytes following stimulation with phorbol 12‐myristate 13‐acetate (PMA) and ionomycin. The percentage of CD3 (T lymphocytes), CD3+ CD4+ (Th lymphocytes), CD3+ CD8+ (T‐suppressor/cytotoxic lymphocytes), CD19+ (B lymphocytes), CD3+ CD4+ CD45RO+ (memory Th lymphocytes), and CD3+ CD4+ CD45RA+ (naive Th lymphocytes) cells was unrelated to parental atopic status. PMA stimulation augmented the percentage of IL‐2‐ and IFN‐γ‐producing Th and T‐suppressor/cytotoxic lymphocytes, whereas the number of IL‐4‐producing T lymphocytes remained very low or undetectable. No differences in the percentage of IL‐2‐, IL‐4‐ and IFN‐γ‐producing Th and T‐suppressor/cytotoxic lymphocytes were found between neonates from atopic and non‐atopic parents. These results will be re‐evaluated when the atopic status of the children at the age of 1 and 2 years can be assessed.
Connections among parent and child atopic illnesses
Authors: Sarafino Edward P.
Published: March 2003

This study investigated parent–child connections for the atopic illnesses of asthma, eczema, food allergies, and hay fever, in a sample of 325 families. Parents reported whether they or their children currently had each condition and rated the frequency and intensity of its episodes; these ratings were combined to estimate illness severity. The data revealed five main findings. First, chi‐square parent–child concordance analyses indicated that children of parents with any of the atopic illnesses studied were significantly more likely to develop that same disease than were children of parents without the illness. Second, children were progressively more likely to have at least one atopic illness when the number of their parents who were atopic increased from zero to two. Third, the number of atopic illnesses in the children was associated with the number of atopic illnesses in the parents. These three findings augment the evidence for genetic factors in the development of atopic illnesses and suggest that the atopies of each parent may contribute to an aggregate, generalized risk for their children. Fourth, maternal atopy was more strongly related to the children's asthma and hay fever than paternal atopy. Fifth, the severity of the children's specific atopic illnesses was not affected by the number of their parents who had the same condition and was not strongly related to the severity of their parents’ condition.
Synthetic pillows contain higher levels of cat and dog allergen than feather pillows
Authors: Custovic Adnan , Hallam Claire , Woodcock Hannah , Simpson Bridget , Houghton Naomi , Simpson Angela , Woodcock Ashley
Published: March 2003

The use of non‐feather pillows has increased over the last few decades. Recently, we found significantly higher levels of dust mite allergens in synthetic pillows than in feather ones. This study investigated the levels of pet allergens in feather and synthetic pillows. Dust samples were collected from 14 pairs of pillows (consisting of one synthetic fibre‐filled and one feather‐filled). Each pair of pillows had been on the same bed for at least 2 years. The pillows were vacuumed for 1 min on each side through a 355‐µm diameter mesh onto a 5‐µm vinyl filter, producing a sample of fine dust. Samples were extracted, and cat (Fel d 1) and dog (Can f 1) allergens determined using monoclonal antibody‐based enzyme‐linked immunosorbent assay (ELISA). Results were expressed both as total amount of allergen recovered and concentration of allergen per unit weight (ng/g). Total levels of pet allergens were significantly higher in the synthetic pillows (Fel d 1: 6.7‐fold difference [95% CI 1.5–29.7], p = 0.01; Can f 1: 8‐fold difference [95% CI 1.6–39.5[, p = 0.01). Similarly, when the results were expressed as µg/g, synthetic pillows contained significantly more allergens than feather pillows (Fel d 1: 3.7‐fold difference [95% CI 1.3–10.1], p = 0.01); Can f 1: 4.4‐fold difference [95% CI 1.5–13.2], p = 0.01). We have therefore demonstrated that synthetic pillows contain significantly more pet allergens than feather pillows, supporting the view that tightly woven encasements surrounding feather pillows act as a barrier for allergens.
Soluble CD30 and CD23 in cord blood are not related to atopy in early childhood
Authors: Øymar Knut , Lærdal Åge , Bjerknes Robert
Published: March 2003

Atopic disease, including atopic dermatitis (AD), is associated with a T‐helper 2 (Th2)‐dependent immune response. The cytokine receptor CD30 appears to be preferentially expressed on, and its soluble form (sCD30) released by, Th2 cells. Therefore, sCD30 may be a potential marker for atopic disorders. The aim of this study was to test the hypothesis that the sCD30 level in cord blood could be used to predict the development of atopy or AD in early childhood. In a case‐control study, levels of sCD30, as well as soluble low‐affinity immunoglobulin E (IgE) receptor (sCD23), interleukin‐4 (IL‐4) and IgE, were measured in cord blood in 35 children who subsequently developed allergic sensitization and AD before the age of three, and the results were compared to those of 35 matched children without a history of atopy. There was no difference in cord blood levels of sCD30 between controls (32.5 U/ml; 19.7–80.1) and children with subsequent atopy and AD (32.2 U/ml; 22–75.9) (median; quartiles). The concentration of sCD30 showed no relation to the levels of total IgE, sCD23 or IL‐4. Levels of sCD23 were similar in children with subsequent atopy (60.2 U/ml; 44.5–76.8) and controls (55.2 U/ml; 38.3–72.5), whereas IL‐4 was detectable in 10 of the atopic children and in only two of the controls (p < 0.05). In conclusion, cord blood levels of sCD30 or sCD23 do not seem to be related to the subsequent development of atopy or AD at the age of three.
Asthma severity and inflammation markers in children
Authors: Wilson Nicola M. , James Anna , Uasuf Carina , Payne Donald N. , Hablas Hatem , Agrofioti Catherine , Bush Andrew
Published: March 2003

The relationship of airway inflammation with asthma severity remains unclear. Our aim was to correlate the results of recommended methods of assessment of inflammation with measures of asthma control, in children with a wide range of asthma severity. The study was a cross‐sectional investigation of 58 children receiving a wide range of treatment, including 10 treated without regular maintenance therapy and 29 treated with high‐dose inhaled corticosteroids (CS). Exhaled nitric oxide (NO), serum eosinophil cationic protein (ECP), and induced sputum (processed for eosinophil count and ECP level) were related to recent symptoms, lung function, and bronchial responsiveness. There was no significant correlation between the results of any method. Neither did any marker of airway inflammation relate to recent symptoms, unlike PC20, which did. There was a significant, inverse correlation between the forced expiratory volume in 1 s (FEV1) and both NO and sputum ECP (r=−0.46, p=<0.001; r=−0.48, p=0.004, respectively). Sputum eosinophils were inversely related to the dose of methacholine that corresponded to a 20% fall in FEV1 (PC20) (r=−0.57, p=0.02). Serum ECP did not relate to any measure of asthma control. There was no association of any recommended inflammation markers with current symptoms and only a weak relationship between them and physiological measures. The place of these markers remains unclear and their use in clinical practice needs further investigation by long‐term longitudinal studies.
Mould‐specific immunoglobulin G antibodies in students from moisture‐ and mould‐damaged schools: A 3‐year follow‐up study
Authors: Immonen Johanna , Laitinen Sirpa , Taskinen Taina , Pekkanen Juha , Nevalainen Aino , Korppi Matti
Published: March 2003

Immunoglobulin G (IgG) antibodies to moulds have been used as biomarkers of mould exposure, though their role reflecting exposure is not confirmed. The purpose of the present study was to evaluate the changes in mould‐specific IgG antibodies in children during a 3‐year follow‐up in relation to changes in exposure, and to allergic and respiratory morbidity. In 1996, 212 primary school students with asthma, wheezing or prolonged cough participated in a clinical study, including clinical examination, skin‐prick tests to 12 moulds and mould‐specific IgG determinations to 24 moulds. In 1999, 144 students of the same cohort participated in an identical follow‐up study; among them, mould‐specific IgG was measured in 121 students. No association was found between IgG antibodies to moulds and exposure to moisture or moulds in schools. Likewise, changes in mould‐specific antibodies were only weakly associated with changes in exposure. Mould‐specific IgG antibodies had no significant association with asthma, wheezing or cough episodes. IgG antibodies to moulds seem to be poor markers of exposure among children exposed to moisture or moulds at school.
An anthroposophic lifestyle and intestinal microflora in infancy
Authors: Alm Johan S. , Swartz Jackie , Björkstén Bengt , Engstrand Lars , Engström Johan , Kühn Inger , Lilja Gunnar , Möllby Roland , Norin Elisabeth , Pershagen Göran , Reinders Claudia , Wreiber Karin , Scheynius Annika
Published: March 2003

The intestinal flora is considered to have an impact on the development of the immune system. In the anthroposophic lifestyle, a diet comprising vegetables spontaneously fermented by lactobacilli, and a restrictive use of antibiotics, anti‐pyretics and vaccinations, is typical. The aim of this study was to assess the gut flora in infants in relation to certain lifestyle characteristics associated with anthroposophy. Sixty‐nine children < 2 years of age with an anthroposophic lifestyle, and 59 infants of a similar age with a traditional lifestyle, were clinically examined and questionnaire replies assessed. Fecal samples were analyzed by bacterial enumeration, bacterial typing through biochemical fingerprinting and by measuring microflora‐associated characteristics (MACs). The numbers of colony‐forming units (CFU)/g of feces were significantly higher for enterococci and lactic acid bacteria in children who had never been exposed to antibiotics (5.5 × 107 vs. 2.1 × 107; p < 0.001 and 10 × 107 vs. 4.1 × 107; p < 0.01, respectively). Furthermore, the number of enterococci was significantly higher in breastfed and vegetarian infants (p < 0.01). The diversity (Simpson's diversity index) of lactobacilli, as determined by biochemical fingerprinting, was higher in infants born at home than in those born in hospital (p < 0.01). Several MACs were related to specific lifestyle features, and infants with an anthroposophic lifestyle had a higher proportion of acetic acid and a lower proportion of propionic acid in their stool as compared to the control children. In conclusion, lifestyle factors related to the anthroposophic way of life influenced the composition of the gut flora in the infants. These differences may contribute to the lower prevalence of atopic disease previously observed in children in anthroposophic families.
Non‐compliance and its management in teenagers
Authors: Nevins Thomas E.
Published: March 2003

Abstract: Renal transplantation restores a patient's endogenous renal function. The benefits of this restoration are especially dramatic in children. However, transplantation is a complex and expensive therapy which, when successful, requires consistent adherence to a complex regimen of drug therapy and clinical follow‐up. Transplant medications need to be taken for a lifetime. Whilst very effective, immunosuppressant medications can also cause a number of side‐effects and require daily multi‐dose schedules. Teenagers, in particular, have problems adhering to these regimens and weighing the consequences of non‐compliance. Approaches to improving teenagers' compliance must address both the special circumstances of adolescence and the broad, general problem of post‐transplant non‐compliance.
Diltiazem retards the metabolism of oral prednisone with effects on T‐cell markers
Authors: Imani S. , Jusko W. J. , Steiner R.
Published: March 2003

Abstract: The area under the time–plasma concentration curve (AUC) was measured for prednisolone (the major active metabolite of prednisone) after ingestion of 15 mg of prednisone (phase 1) and again after 3 d of oral diltiazem (180 mg/d) followed by the same dose of oral prednisone (phase 2) in eight normal adult patients. Diltiazem increased the prednisolone AUC by 21% (range 3–38%), from 1297 ± 157 ng/h/mL to 1560 ± 169 ng/h/mL (p=0.001). This effect was associated with a greater decrease from baseline in CD3+ lymphocyte number at 4 h after prednisone ingestion (596 ± 175 vs. 516 ± 140, p=0.05), a larger percentage decrease of circulating CD3+ lymphocytes at 8 h (43 ± 19% vs. 53 ± 19%, p=0.04), and a decrease in the number of CD3+ CD8+ T cells at 4 h post‐prednisone ingestion (279 ± 81 vs. 236 ± 51, p=0.04). Diltiazem retards prednisolone metabolism and when used chronically with prednisone could conceivably, in some patients, enhance its immunologic and other clinical effects. Potentiation of prednisone side‐effects by diltiazem may be of special interest in pediatric patients, and possible diltiazem–prednisone interactions merit study in this population.
Gene therapy of genetic diseases and cancer
Authors: McIvor R. Scott
Published: March 2003

Abstract: The scope of gene transfer applications in human therapy has expanded enormously over the last 15 years to include not only several types of genetic diseases but also a variety of genetic approaches to the treatment of cancer. Hematopoietic stem cells have been considered excellent targets for therapeutic gene transfer because of their capacity for self‐renewal and for differentiation into multiple cellular lineages. Retrovirus‐mediated gene transfer has been tested for treatment of diseases that specifically affect the hematopoietic system, such as adenosine deaminase deficiency and chronic granulomatous disease. Storage disorders such as Gaucher disease, Hurler syndrome and Hunter syndrome, genetic deficiencies that affect a broad range of tissue types, may also be amenable to treatment by gene transfer into hematopoietic cells, owing to the release of enzyme expressed in transduced cells with subsequent uptake by untransduced cells (“metabolic cross‐correction”). Hematopoietic stem cells may also be targeted for introduction of drug‐resistance genes for the purpose of protecting normal tissues from the toxic side‐effects of cancer chemotherapeutic agents, thus allowing more effective antitumor chemotherapy. The danger of introducing drug‐resistance function into tumor cells may be dealt with by including sequences specifically designed to reduce expression of oncogenes or to restore expression of tumor suppressor genes. Current limitations on the efficiency of gene transfer into hematopoietic stem cells may be alleviated by the development of new vector systems such as adeno‐associated virus or lentivirus vectors, or by advances in cell processing that render hematopoietic cells more susceptible to transduction. Drug‐resistance genes may also be applied for in vivo selection to expand the representation of a small proportion of transduced hematopoietic cells. These approaches toward increasing the frequency of hematopoietic cell transduction contribute to the anticipated feasibility of gene therapy for genetic diseases and cancer.
Inappropriate liver transplantation in a child with Alpers–Huttenlocher syndrome misdiagnosed as valproate‐induced acute liver failure
Authors: Delarue A. , Paut O. , Guys J. ‐M. , Montfort M. ‐F. , Lethel V. , Roquelaure B. , Pellissier J. ‐F. , Sarles J. , Camboulives J.
Published: March 2003

Abstract: A 3‐yr‐old boy received valproic acid (VPA) for recurrent seizures. He developed coma and acute liver failure that were attributed to VPA toxicity, and underwent emergency orthotopic liver transplantation (OLTx). Despite good graft function, his neurological state worsened and led to death a few months later. The diagnosis of Alpers–Huttenlocher Syndrome (AHS) was suspected, subsequently to liver Tx, in view of ongoing neurologic deterioration and magnetic resonance imaging (MRI) findings. The syndrome, recessively inherited, associates brain degeneration with liver failure, and is now considered a mitochondrial disease. Enzyme activity deficiencies of the respiratory chain were identified in muscle mitochondria, as well as morphologic abnormalities of mitochondria in the explanted liver. Guidelines for diagnosis are presented, in order to differentiate the liver failure in AHS from that induced by genuine VPA toxicity. It is recommended to avoid liver Tx in patients with AHS given the fatal neurological course of the disease.
Do six‐antigen‐matched cadaver donor kidneys provide better graft survival to children compared with one‐haploidentical living‐related donor transplants? A report of the North American Pediatric Renal Transplant Cooperative Study
Authors: Tejani Amir , Sullivan E. Kenneth
Published: March 2003

Abstract: Since 1991, more than 50% of pediatric transplant recipients have received a living donor (LD) kidney, and ≈ 85% of these allografts were one‐haploidentical parental kidneys. Short‐term (1 yr) and long‐term (5 yr) graft survival of LD kidneys are 10% and 15% better, respectively, than that of cadaver donor (CD) kidneys. Because of these results, children are frequently not placed on a cadaver waiting list until the possibility of a LD is excluded – a process that may take up to 1 yr. The hypothesis for this study was that the graft outcome of a six‐antigen‐matched CD kidney is superior to that of a one‐haploidentical LD kidney, and that children are at a disadvantage by not being placed on a CD list whilst waiting for a LD. The database of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) for 11 yrs (1987–98), was reviewed to identify children who were recipients of a six‐antigen‐matched CD kidney (primary and repeat transplants), and those who were recipients of a one‐haploidentical LD kidney (primary and repeat transplants). Using standard statistical methods, the morbidity, rejection episodes, post‐transplant hospitalizations, renal function, long‐ and short‐term graft survival, and half‐life of primary recipients were compared in the two groups. Unlike adult patients, only 2.7% (87/3313) of CD recipients in the pediatric age range received a six‐antigen‐matched kidney, and the annual accrual rate over 11 yrs was never higher than 4%. Comparison of 57 primary six‐antigen‐CD kidneys (PCD) with 2472 primary LD (PLD) kidneys revealed that morbidity, rejection rates, and ratios were identical in the two groups. Renal function and subsequent hospitalizations were also identical in the two groups. Five‐year graft survival of the PCD group was 90% compared with 80% for the PLD group, and the half‐life of the PCD group was 25 ± 12.9 yrs compared with 19.6 ± 1.3 yrs. Our data suggest that the six‐antigen‐matched CD kidney may have less graft loss as a result of chronic rejection and would therefore confer a better long‐term outcome. Based on these findings we recommend that all children, whilst waiting for a LD work‐up, be listed with the United Network for Organ Sharing (UNOS) registry for a CD kidney.
Concomitant basiliximab with low‐dose calcineurin inhibitors in children post‐liver transplantation
Authors: Arora N. , McKiernan P. J. , Beath S. V. , DeVille De Goyet J. , Kelly D. A.
Published: March 2003

Abstract:Orthotopic liver transplantation (OLT) is effective therapy for end‐stage liver disease but immunosuppression with calcineurin inhibitors (CNI) leads to significant nephrotoxicity, resulting in either a reduction of dosage to below the therapeutic level or omission of the drug altogether. Basiliximab (Bx) is a human/mouse chimeric monoclonal antibody that inhibits binding of interleukin‐2 (IL‐2) to IL‐2 receptors and thus prevents proliferation of T cells, which is the main step in the development of acute cellular rejection. The aim of this study was to identify the role of Bx in the prevention of acute cellular rejection and in the reduction of nephrotoxicity in children post‐liver transplantation. We evaluated three children (19 months, 22 months, and 11 yr of age; one male, two female) who were treated with Bx post‐OLT on compassionate grounds. The indications were: nephrotoxicity in two children, requiring re‐transplantation for hepatic artery thrombosis and recurrent giant cell hepatitis, respectively; and nephrotoxicity secondary to chemotherapy for hepatoblastoma in the third child. All patients received 10 mg of Bx, at OLT and on Day 4. Tacrolimus (0.15 mg/kg/day) was started at 48 h (n = 2) and cyclosporin (5 mg/kg/day) at 2 weeks (n = 1). Trough levels of tacrolimus were maintained at 5–8 ng/mL and trough levels of cyclosporin at 100–150 mg/L for the first 3 months. All patients received methylprednisolone (2 mg/kg) with azathioprine (1.5 mg/kg) (n = 2) and/or mycophenolate mofetil (20 mg/kg) (n = 1). The glomerular filtration rate (cGFR) was calculated using the Schwartz formula before and 10 weeks after transplant. Bx was found to be easy to administer and no major side‐effects were reported. One child had two episodes of mild acute rejection at 5 and 9 weeks post‐OLT and one developed chronic rejection requiring re‐transplantation at 9 weeks post‐OLT. One child did not develop rejection. The mean pretransplant cGFR was 58.1 (54.6–64.1) mL/min/m2. Within 10 weeks of transplantation, the cGFR had improved by 69% to a mean of 116 (88–157.6) mL/min/m2. To conclude, Bx was well tolerated in all children and had a renal sparing effect. It was effective in preventing early acute rejection, but the combination of Bx and low‐dose CNI drugs did not prevent late acute or chronic rejection. Further studies to evaluate the appropriate levels of CNI immunosuppression with Bx are required.
Repeated detection of gas in the portal vein after liver transplantation: A sign of EBV‐associated post‐transplant lymphoproliferation?
Authors: Wallot Michael A. , Klepper Jörg , Clapuyt Philippe , Dirsch Olaf , Malagó Max , Reding Raymond , Otte Jean Bernard , Sokal Etienne M.
Published: March 2003

Abstract: A 1‐yr‐old child presented with intractable right sided pleural effusion and progressive clinical deterioration 3 weeks after liver transplantation for Alagille Syndrome. He had been treated successfully for severe acute rejection before. Ultrasound and Doppler mode studies repeatedly demonstrated air in the portal vein. Intra‐abdominal and intra‐thoracic lymphoproliferation was detected, and EBV virus load and serology were suggestive of primary EBV infection. Liver biopsy revealed blast‐like infiltrates of B‐cells, considered diagnostic for post‐transplant lymphoproliferative disease. The disease resolved upon reduction of immunosuppression. We suggest that the detection of portal vein gas in pediatric liver transplant recipients beyond the early post‐operative period may be a sign of intra‐abdominal post‐transplant lymphoproliferative disease.
Marked hyperbilirubinemia caused by acute cellular rejection combined with preservation injury in an infant undergoing living‐related liver transplantation
Authors: Hasegawa Toshimichi , Sasaki Takashi , Kimura Takuya , Oimatsu Natsumi , Okada Akira , Mushiake Sohtaro , Hoshida Yoshihiko , Dono Keizo , Kato Tomoaki
Published: March 2003

Abstract:Acute cellular rejection (ACR) and preservation injury (PI) are major complications occurring early after liver transplantation (LTx) and sometimes lead to severe graft dysfunction. We herein report an infant who developed marked hyperbilirubinemia as a result of combined ACR and PI in addition to ischemic damage from bleeding, but recovered without re‐LTx. In a 1‐yr‐old‐girl undergoing living‐related LTx, liver biopsy (LBx) on post‐operative day 7 showed ballooning of the hepatocytes, i.e. microvesicular steatosis (30%) and occasional centrolobular necrosis, consistent with mild‐to‐moderate PI and ACR with a rejection activity index (RAI) of 2.0. Because drainage of an intra‐abdominal abscess was performed and a systemic infection was considered severe, the tacrolimus level was decreased and steroids were discontinued. The total bilirubin level started to rise, thereafter, reaching a maximum of 47.6 mg/dL at 1 month after LTx. LBx showed an RAI of 6.0 and steatosis of 10%. With good response to an increase of tacrolimus level and administration of steroid, the total bilirubin level gradually decreased, finally reaching the normal range in 3 months, and LBx showed no steatosis or finding of ACR. From this experience, ACR, if combined with mild‐to‐moderate PI or other ischemic damage, may lead to severe clinical manifestations after LTx, which, however, could remit with conservative therapy and without re‐LTx.
Unrelated donor stem cell transplant: donor selection and search process
Authors: Karanes Chatchada
Published: March 2003

Abstract: The article describes the unrelated donor and cord blood search process through the National Marrow Donor Program (NMDP) for practising hematologist‐oncologists and stem cell transplant physicians. The recent changes in the diseases, type of transplants and stem cell sources are discussed. Important data showing the effects of HLA loci and non‐HLA factors on the transplant outcome, including new services offered by NMDP were reviewed.
Genetic analysis of chloroplast biogenesis in higher plants
Authors: Barkan Alice , Voelker Rodger , Mendel‐Hartvig Janet , Johnson David , Walker Macie
Published: March 2003

The biogenesis of chloroplasts is genetically complex, involving hundreds of genes distributed between the nucleus and organelle. In higher plants, developmental parameters confer an added layer of complexity upon the genetic control of chloroplast biogenesis: the properties of plastids differ dramatically between different cell types. While the biochemistry and structure of different plastid types have been described in detail, factors that determine the timing and localization of chloroplast development and that mediate chloroplast assembly have remained elusive. To identify nuclear genes that play novel roles in chloroplast biogenesis, we are exploiting nuclear mutations that block the accumulation of subsets of chloroplast proteins. Detailed study of the mutant phenotypes provides clues concerning the primary defect in each mutant. Mutants with defects in chloroplast translation and mRNA metabolism have been identified. Other mutants defective in the accumulation of multiple thylakoid complexes show no apparent defect in the synthesis of the missing proteins. These may identify factors involved in the integration of proteins into the thylakoid membrane and their assembly into functional complexes.
Expression of thiol proteases decreases in tomato ovaries after fruit set induced by pollination or gibberellic acid
Authors: Agüero Marta S. , Granell Antonio , Carbonell Juan
Published: March 2003

The modulation of the expression of thiol proteases during both senescence and development was investigated Proteolytic activity and some thiol proteases were analyzed in unpollinated tomato (Lycopersicon esculentum Mill. cv. Rutgers) ovaries during presenescence and during early fruit development induced by treatment with gibberellic acid (GA) or by natural pollination. Proteolytic activity in extracts was tested on azocasein and by observing degradation of the ribulose‐1,5‐bisphosphate carboxylase large subunit in western blots. There was no correlation between total activity and protein content. Thiol proteases were analyzed by western blot with antibodies raised against papain and a recombinant tomato C14 thiol protease. A 58‐kDa polypeptide was recognized by both antibodies and two more polypeptides of 47 and 36 kDa were detected with the second one. All these polypeptide levels increased in untreated unpollinated ovaries at the presenescent stage. Natural pollination or GA treatment of unpollinated ovaries resulted in decreases of these polypeptides at an early developmental stage. The same pattern was observed for the levels of C14 mRNA. Our results suggest that the expression of C14 thiol protease occurs in unpollinated ovaries at the presenescent stage and that it can be suppressed by factors that induce fruit set and development.
Endo‐1,4‐β‐glucanase gene expression and cell wall hydrolase activities during abscission in Valencia orange
Authors: Burns Jacqueline K. , Lewandowski Dennis J. , Nairn C. Joseph , Brown G. E.
Published: March 2003

The physiological and molecular events of ethylene‐induced abscission in mature fruit calyx, laminar and floral abscission zones of cv. Valencia orange were examined. Continuous exposure of fruit explants to 5 µl 1−1 ethylene for 2 to 40 h resulted in marked increases in endo‐1,4‐β‐glucanase (cellulase) and polygalacturonase (PG) activities in calyx abscission zones. Two abscission‐related cellulases and one PG were found. The major peak of cellulase activity corresponded to a pI of 8.0 and molecular weight of 51 kDa, whereas the minor cellulase peak had a pI of 5.5. The abscission polygalacturonase had a pI of 5.5. Calyx abscission zone RNA was amplified with degenerate primers based on sequence of the purified Valencia orange calyx abscission cellulase, and cloned. The two partial cellulase cDNA clones were 59% identical at the nucleotide level. Genomic Southern analysis suggested that Valencia orange contained two groups of cellulase genes. A full‐length cDNA clone from each group was isolated from a cDNA library prepared from ethylene‐induced calyx abscission zone mRNA. Both genes were expressed in ethylene‐induced calyx, laminar and floral abscission zones, but were not expressed in non‐induced abscission zones or mature leaves treated with or without ethylene, young bark or young fruit of Valencia.
Autotropism, automorphogenesis, and gravity
Authors: Stanković Bratislav , Volkmann Dieter , Sack Fred D.
Published: March 2003

Segments of organs that have undergone gravitropic curvature later straighten during the course of gravitropism or after the g‐vector becomes randomized on a clinostat. Little is known about the mechanisms underlying these and perhaps related phenomena which have been described with various overlapping terms such as autotropism, autotropic straightening, automorphosis, automorphogenesis, automorphic curvature, and gravitropic straightening. The types of phenomena that historically have been named by the above terms are reviewed critically with respect to an interaction with gravitropism. We suggest that the term “autotropism” should not be applied to the phenomenon of organ straightening that occurs during the course of gravitropism, since this straightening is part of a complex series of local growth adjustments overall through time, and since this phenomenon is not itself a tropistic response to a directional exogenous stimulus. It is suggested that the term autotropism should be used only for the phenomenon of organ straightening that occurs after the g‐vector is randomized on a clinostat or withdrawn in the microgravity conditions of spaceflight. Usage of the term automorphogenesis is most appropriate for describing curvatures or orientations that result from morphological relationships such as in nastic curvatures.
Interactive effects of growth‐limiting N supply and elevated atmospheric CO2 concentration on growth and carbon balance of Plantago major
Authors: Den Hertog Jeroen , Stulen Ineke , Posthumus Freek , Poorter Hendrik
Published: March 2003

To assess the interactions between concentration of atmospheric CO2 and N supply, the response of Plantago major ssp. pleiosperma Pilger to a doubling of the ambient CO2 concentration of 350 µl l−1 was investigated in a range of exponential rates of N addition. The relative growth rate (RGR) as a function of the internal plant nitrogen concentration (Ni), was increased by elevated CO2 at optimal and intermediate Ni. The rate of photosynthesis, expressed per unit leaf area and plotted versus Ni. was increased by 20‐30% at elevated CO2 for Ni above 30 mg N g−1 dry weight. However, the rate of photosynthesis, expressed on a leaf dry matter basis and plotted versus Ni, was not affected by the CO2 concentration. The allocation of dry matter between shoot and root was not affected by the CO2 concentration at any of the N addition rates. This is in good agreement with theoretical models. based on a balance between the rate of photosynthesis of the shoot and the acquisition of N by the roots. The concentration of total nonstructural carbohydrates (TNC) was increased at elevated CO2 and at N limitation, resulting in a shift in the partitioning of photosynthates from structural to nonstructural and, in terms of carbon balance, unproductive dry matter. The increase in concentration of TNC led to a decrease in both specific leaf area (SLA) and Ni at all levels of nutrient supply, and was the cause of the increased rate of photosynthesis per unit leaf area. Correction of the relationship between RGR and Ni for the accumulation of TNC made the effect of elevated CO2 on the relationship between RGR and Ni disappear. We conclude that the shift in the relationship between RGR and Ni was due to the accumulation of TNC and not due to differences in physiological variables such as photosynthesis and shoot and root respiration, changes in leaf morphology or allocation of dry matter.
The amelioration of aluminium toxicity by silicon in higher plants: Solution chemistry or an in planta mechanism?
Authors: Cocker Kay M. , Evans David E. , Hodson Martin J.
Published: March 2003

Aluminium (Al) toxicity is a very important factor limiting the growth of plants on acidic soils. Recently, a number of workers have shown that, under certain conditions, silicon (Si) can ameliorate the toxic effects of A1 in hydroponic culture. The mechanism of the amelioration is unclear, but three suggestions have been put forward: Si‐induced increase in solution pH during the preparation of hydroponic solutions; reduced availability of Al due to the formation of hydroxyaluminosilicate (HAS) species in those solutions during plant growth; or in planta detoxification. It is now known that it is possible to make up Al and Si solutions in an order in which pH is lowered prior to Al addition; in these cases amelioration has still been observed. Amelioration has also been noted in experiments where HAS formation is minimal. These observations would suggest that, at least under some circumstances, there is an in planta component to the amelioration phenomenon. Several microanalytical investigations have noted codeposition of Al and Si in root cell walls. We propose a model in which root cell walls are the main internal sites of aluminosilicate (AS) and/or HAS formation and of Al detoxification. Factors promoting AS/HAS formation in this compartment include: high apoplastic pH; the presence of organic substances (e.g. malate); and the presence of suitable local concentrations of reactive forms of Al and Si, on or within the surfaces of the wall matrix. All these are likely to be important in the amelioration of Al toxicity.
Chilling‐induced leaf abscission of Ixora coccinea plants. II. Alteration of auxin economy by oxidative stress
Authors: Michaeli Rina , Riov Joseph , Philosoph‐Hadas Sonia , Meir Shimon
Published: March 2003

Chilling‐induced leaf abscission of ixora (Ixora coccinea) plants was almost completely inhibited by α‐naphthaleneacetic acid (NAA), even in the presence of exogenous ethylene, which enhanced the chilling effect on leaf abscission. Chilling reduced free indoleacetic acid (IAA) content, quantified immediately after chilling, in the abscission zone (AZ) and leaf blade. Free IAA content in chilling‐treated plants continued to decrease gradually with time after chilling. Application of the antioxidant butylated hydroxyanisole (BHA) before or after chilling not only prevented the post‐chilling decline in free IAA content, but also restored free IAA level during 6–48 h of the post‐chilling period almost to the control level. No significant effect of chilling on the endogenous content of ester‐ and amide‐conjugates of IAA or the metabolism of exogenous labeled IAA were observed. Chilling enhanced the decarboxylation of IAA, particularly in the AZ tissue. Auxin transport capacity was significantly inhibited by chilling, and this effect was counteracted by BHA applied before chilling. The data indicate that chilling reduces free IAA content in the AZ, an effect that may lead to increased sensitivity to ethylene. The chilling‐induced reduction in IAA content in the AZ seems to result, at least in part, from increased IAA decarboxylation and reduced auxin transport capacity. These processes seem to be triggered by the oxidative stress imposed on the tissues by chilling.
Green fluorescent protein as a reporter system in the transformation of barley cultivars
Authors: Ahlandsberg Staffan , Sathish P. , Sun Chuanxin , Jansson Christer
Published: March 2003

A cereal transformation vector, pN1473, containing the strong constitutive rice actin promoter Act‐1, a multiple cloning site, and the nos terminator, was constructed. Fusion of a plant‐optimized gfp gene to Act‐1 in pN1473 resulted in the vector pN1473GFP. To assess the suitability of pN1473, and GFP as a reporter system in barley transformation, two barley cultivars (Baronesse and Golden Promise) were transformed by microprojectile bombardment. Transient gfp expression in transformed embryogenic callus material was detectable by fluorescence microscopy less than 12 h after transformation. The presence of the gfp gene in callus and regenerated plantlets was confirmed by PCR amplification and DNA gel‐blot analysis.
The effect of mechanical impedance on root growth in pea (Pisum sativum). I. Rates of cell flux, mitosis, and strain during recovery
Authors: Croser Clare , Bengough A. Glyn , Pritchard Jeremy
Published: March 2003

We studied the effect of mechanical impedance on cell flux and meristematic activity in pea roots. Pea seedlings (Pisum sativum L. cv. Helka) were grown in cores of sand packed to dry bulk densities of either; 1.4 Mg m−3 with an additional 2.4 kg uniaxial load applied to the surface to increase the mechanical resistance to growth (penetration resistance of 1.5 MPa); or 1.0 Mg m−3 (penetration resistance of 0.05 MPa). A water content of 0.06 g g−1 was chosen for optimum root growth. After 3 days, the seedlings were transferred to hydroponics, colchicine was added and the rate of cell doubling, mitotic index and length of the cell cycle was assessed. Cell flux in the third cortical layer was calculated for roots immediately removed from sand.Mechanical impedance slowed root extension to about 20% of the unimpeded rate, and final cell length was reduced to 50% of the unimpeded length. The rate of cell doubling was 3.4 times slower for roots recovering from mechanical impedance mostly as a result of a longer period spent in interphase. Cell flux in impeded roots was approximately half that of unimpeded roots (5 cells h−1), and contributed to a shorter cell file and elongation zone, and a slower rate of root elongation.