bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulation of Arabidopsis thaliana Em genes: role of ABI5
Authors: Carles Cristel , Bies‐Etheve Natacha , Aspart Lorette , Léon‐Kloosterziel Karen M. , Koornneef Maarten , Echeverria Manuel , Delseny Michel 
Published: March 2003

SummaryIn order to identify new factors involved in Em (a class I Late Embryogenesis Abundant protein) gene expression, Arabidopsis mutants with an altered expression of an Em promoter GUS fusion construct and a modified accumulation of Em transcripts and proteins were isolated. Germination tests on ABA showed that the most affected mutant had a weak abi phenotype. Complementation tests further revealed this mutant to be a new abi5 allele, consequently named abi5–5. In addition to reducing the final level of Em transcripts in the dry seed, the abi5–5 mutation causes a delay in the accumulation of AtEm1 during seed development. An additional characteristic of the abi5–5 mutant, is the ability of its seeds to germinate at high concentrations of salt and mannitol. The abi5–5 mutation was characterized at the molecular level and was shown to result from a two base pair deletion in the coding sequence of the ABI 5 gene. The wild type and mutant recombinant proteins were produced in E. coli and were assayed for DNA‐binding activity on their target promoters by electrophoretic mobility shift assay (EMSA). The ABI5 recombinant protein binds the ABRE sequence in the AtEm6 promoter as shown by Dnase footprinting. Among the ABRE‐type sequences selected on both Em promoters, the G‐box type AGACACGTGGCATGT element of the AtEm6 promoter shows the strongest binding by EMSA quantification.
Multiple plastid signals regulate the expression of the pea plastocyanin gene in pea and transgenic tobacco plants
Authors: Sullivan James A. , Gray John C. 
Published: March 2003

SummaryThe expression of nuclear genes encoding photosynthesis‐related proteins is regulated by signals from plastids. To investigate how the pea PetE gene encoding plastocyanin is regulated by plastid signals, the effects of norflurazon, lincomycin and 3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea (DCMU), specific inhibitors of plastid‐located processes generating plastid signals, have been examined. RNA‐gel blot analysis of 7‐day‐old pea and tobacco seedlings containing the pea PetE gene showed that treatment with norflurazon and lincomycin, but not DCMU, decreased the accumulation of transcripts of pea PetE and endogenous Lhcb1 genes. Analysis of chimeric PetE gene constructs in tobacco seedlings showed that an intact PetE mRNA 5′ terminus and elements within the PetE coding region were required to confer sensitivity to norflurazon and lincomycin, suggesting post‐transcriptional regulation. Analysis of 4‐week‐old tobacco plants containing chimeric PetE constructs showed that DCMU treatment decreased the accumulation of pea PetE and Lhcb1 transcripts, but had opposite effects on the transcription of the genes in nuclear run‐on assays. DCMU upregulated transcription from the pea PetE promoter whereas transcription of tobacco Lhcb1 genes was decreased. These experiments provide evidence for multiple plastid signals operating at different developmental stages and affecting transcriptional and post‐transcriptional processes regulating expression of the pea PetE gene.
Identification of an essential component of the elicitation active site of the EIX protein elicitor
Authors: Rotblat Barak , Enshell‐Seijffers David , Gershoni Jonathan M. , Schuster Silvia , Avni Adi 
Published: March 2003

SummaryDefense mechanisms of plants against pathogens often entail cell wall strengthening, ethylene biosynthesis, expression of pathogen‐related proteins and hypersensitive responses (HR). Pathogen‐derived elicitors trigger these defense responses. The Elicitor Ethylene‐inducing Xylanase (EIX) elicits HR and other plant defense responses in some tobacco and tomato cultivars independently of its xylan degradation activity. The elicitation epitope on the EIX protein responsible for inducing the HR response has been elucidated. Through the generation of EIX‐specific polyclonal antibodies and screening of combinatorial phage display peptide libraries an essential sequence of the EIX elicitation activity has been identified. This sequence consists of the pentapeptide TKLGE mapped to an exposed β‐strand of the EIX protein. Substitution of the pentapeptide TKLGE to VKGT inhibited the elicitation activity but not the β‐1‐4‐endoxylanase activity of the EIX protein further demonstrating that elicitation and enzyme activity are independent properties. Elucidation of a peptide sequence that is essential for elicitation of HR creates the opportunity to understand the control and signaling of plant defense.
HLA class II Ab in TRALI donors
Authors: Lubenko A. , Rodi K. , Savage J. , Hilton D. 
Published: March 2003

TRALI (Transfusion Related Acute Lung Injury) occurs in 11–16 patients and is associated with 3–4 deaths per year in the UK. It is caused by HLA (e.g. anti‐HLA‐A2), neutrophil (e.g. anti‐NA2) and leucocyte‐panreactive (e.g. anti‐5b) Ab. Recently an IvIg preparation enriched for HLA class I and II Ab caused TRALI in an untransfused male volunteer (Dooren et al. Lancet 1998; 358: 1601–1602). We therefore ascertained the incidence of class II Ab in sera in donors implicated in TRALI using commercial ELISA kits.Sera from 32 donors were tested for HLA class II antibodies using GTI B‐Screen ELISA kits. All of these sera had previously been tested for leucocyte‐reactive Ab using the GLAM assay, and for HLA class I Ab by LCT and ELISA (GTI QuikScreen® kits). The following reaction patterns were obtained:Hence HLA class II Ab were detected in 8/32 (25%) of sera implicated in TRALI. We suspect that they are more frequent than neutrophil‐specific Ab in TRALI donors: we identified the latter in only 8/123 (6·5%) donors tested in the course of investigating 31 TRALI cases, i.e. in 6/21 (28%) donors who were LCT‐GLAM+ and in 2/9 (22%) who were LCT+GLAM+.
Anti‐HPA1a antibodies induce CD62P and fibrinogen binding
Authors: Koren D. , Janisiw M. , Eichelberger B. , Panzer S. 
Published: March 2003

B ackground Alloantibodies to platelet antigens may affect platelet function by delivering stimulatory or inhibitory signals or by occupying platelet receptor‐ligand molecules. So far, reports from the literature are controversial.M ethods We investigated CD62P and CD63 expression, as well as fibrinogen‐binding on platelets that have been incubated with sera containing anti‐HPA‐1a (NAIT, n = 11; PTP, n = 5) by flow cytometry. HPA‐1a/a platelets from HLA‐matched donors were incubated with antisera and then stimulated with TRAP‐6 (20 µm and 50 µm) to study stimulatory or inhibitory effects.R esults  NAIT: TRAP‐6 20 µm and 50 µm induced CD62P expression was enhanced by 2 and 4 sera, respectively. Fibrinogen binding was induced by 6 sera and enhanced if with TRAP‐6 20 µm and 50 µm by 3 and 8 sera, respectively. PTP: 2 sera induced CD62P and all 5 augmented its TRAP‐6 50 µm induced expression. Fibrinogen binding was induced by 4 sera and all 5 sera enhanced its TRAP‐6 50 µm induced binding. There were no changes in the CD63 expression.C onclusions HPA‐1a antibodies activate platelets to release CD62P and support fibrinogen binding. These effects are stronger in PTP than in NAIT.
Anti‐D (WinRho‐SD) is associated with more than one mechanism of action in autoimmune thrombocytopenic purpura (AITP)
Authors: Semple J. W. , Speck E. R. , Kim M. , Blanchette V. , Freedman J. 
Published: March 2003

We have shown that the treatment of children with chronic AITP with anti‐D is associated with a transient elevation of several pro‐and anti‐inflammatory serum cytokines followed by a gradual reduction in leucocyte phagocytosis and increase in platelet count (Semple et al. Blood 92: 178a, 1998). To further study these observations, we developed an in vitro phagocytosis assay using fluorescently labelled opsonized bacteria and flow cytometry. Results show that when anti‐D was titrated into whole peripheral RhD + blood, the phagocytic activity of individual granulocytes and monocytes was transiently increased whereas the percentage of cells able to be recruited to phagocytosis was significantly inhibited within 30 min and lasted for up to 8 h. This was not seen in RhD‐blood. In control experiments using intravenous gammaglobulin (IVIg), similar finding were observed but to a lesser degree compared with anti‐D. When the anti
d‐treated peripheral blood was analysed for intracellular cytokines by flow cytometry, monocytes produced detectible levels of IL‐1 receptor antagonist, IL‐6 and TNF‐within 1 h after the addition of anti‐D. These in vitro results appear to mimic the in vivo observations in children with chronic AITP and suggest that anti‐D may transiently activate cells of the RES which is followed by a gradual reduction in phagocytic potential. Thus, like IVIg, anti‐D may have more than one mechanism of action.
Frequency determination of RhD specific B‐lymphocytes in RhD antagonism
Authors: Mulder A. , Eijsink C. , Van Dijk M. E. I. Franke‐. , Kardol M. J. , Van Marion J. , Ten Asbroek M. , Doxiadis I. I. N. , Claas F. H. J. , Brand A. 
Published: March 2003

Immunoprophylaxis with Rh‐D immunoglobulin has been proven effective for the prevention of haemolytic disease of the newborn (HDN) in > 90% of cases. At present, anti RhD immunoglobulin is prepared from plasma of volunteer RhD‐donors who are immunized with RhD+ erythrocytes, while human monoclonal RhD antibodies (RhD‐HuMAbs) are in development. Selection of donors is entirely based on the progression of plasma RhD antibody titre during the course of repeated boosting. Donor selection would improve if a predictive test were available for estimating the number of B‐lymphocytes involved in RhD antibody secretion.We have developed a B cell precursor assay (BCPF) for specific antibody producing cells. Immunomagnetically isolated CD19+ B‐cells are cultured for 10 days in limiting dilution format and supernatants are tested for the presence of agglutinating antibodies. We validated this method using B‐cells from women immunized by pregnancy or deliberate immunization. RhD specific BCPF values were found to range from 42 to 16000 per 106 B‐cells in immunized women. We are currently correlating serum RhD antibody agglutination titres with RhD‐BCPF titres.This method will be useful for: (i) prediction of donors who will or will not develop high titreed RhD antibodies upon boosting; (ii) evaluation of the efficiency of immunoprophylaxis in the presence of passive antibodies; (iii) evaluation of the downregulating effects of immunosuppressive drugs or agents on B‐cells; (iv) assessing donor suitability for RhD‐HuMAb hybridoma development.
HPA‐1, ‐2 and ‐3 genotyping using the TaqMan™ reaction
Authors: Hurd C. , Ocheja A. , Cheetham‐Wilkinson C. , Ouwehand W. 
Published: March 2003

Human platelet alloantigen (HPA) genotyping is widely used (i) in the diagnosis and management of the alloimmune thrombocytopenias; (ii) in the HPA typing of donor panels for the provision of HPA‐matched blood products; and (iii) in the study of HPA and cardiovascular disease association.We describe HPA‐1, ‐2 and ‐3 genotyping by allelic discrimination using the Taqman™ reaction. The assay combines the PCR reaction, using platelet glycoprotein‐specific primers, with the release of a reporter fluorophore from an allele‐specific oligonucleotide probe by the 5′−3′ exonuclease activity of Taq polymerase. By using two differently labelled allele‐specific probes and in situ measurement of released fluorescence, the genotype of each biallelic system can be determined in a single PCR reaction without additional post‐PCR manipulation.The TaqMan™ assay has been compared with the PCR using allele specific primers (PCR‐SSP) evaluated by ethidium bromide staining in agarose gels. Parallel testing of 253 genomic DNA samples showed that the TaqMan™ assay to be more consistent and to be independent of subjective interpretation errors. Subjective reading of weak bands accounted for the misinterpretation of the PCR‐SSP evaluated on ethidium bromide gels. The TaqMan™ reaction is readily adaptable to high throughput genotyping by automation of the dispensing and data handling steps.
Platelet gel as a new routine method to improve wound healing and tissue regeneration
Authors: Sacchi M. C. , Maresca P. , Tartuferi L. , Bellanda M. , Micheletti P. , Riva S. , Borzini P. , Levis A. , Rosti G. 
Published: March 2003

I ntroduction Previous data showed that platelets contain growth factors (PDGF, FGF, EGF, TGF‐β) that stimulate capillary endothelial migration (angiogenesis), fibroblast proliferation and migration, and collagen synthesis. Nowadays the platelet gel is considered a useful and available tool to increase either the quality or the final quantity of new‐conformed bone and to stimulate repair of chronic ulcers resulting in accelerated granulation tissue formation and epithelization. By thinking about the importance to use the platelet gel in surgery and in the treatment of ulcers, an efficient, reliable, reproducible, standardized, easy, safe and economic technique has been recently set up, which permits to obtain quickly an autologous platelet gel in laboratory so it can be used as routine in oral, implant, maxillofacial surgery and in attempt to accelerate the healing of chronic wounds.P atients and M
ethods All patients were given informed consent before inclusion in the study. PC, prepared starting from a low quantity of whole blood (60 mL), is activated by a Batroxabine‐calcium gluconate blend to obtain a platelet gel.R esults We observed, after about 5 weeks from the first application, the recovery of three of the nine treated patients suffering from chronic wounds to lower limb. Till now, the excellent initial results obtained consist in an improvement in the cleansing, in a reduction in ulcer sizes and, for all patients, in an improvement in the painful symptomatology. Furthermore, in implant surgery it has been demonstrated that the application of a platelet gel into bone graft produces, five months after the surgery, a neo‐formed bone considerably radiopaque as pointed out by the T.C. exam and confirmed by the hystological analysis.
Field evaluation of a one‐step dipstick assay for the diagnosis of human leptospirosis in the Seychelles
Authors: Yersin Claude , Bovet Pascal , Smits Henk L. , Perolat Philippe 
Published: March 2003

Summary objective and method  To compare the response of a dipstick assay (DSA) detecting Leptospira‐specific immunoglobulin M (IgM) antibodies with that of an enzyme‐linked immunosorbent assay (ELISA), an indirect haemagglutination assay (IHA), the microagglutination test (MAT) and a polymerase chain reaction assay (PCR) in patients with leptospirosis confirmed by MAT alone or by MAT and/or PCR (MAT/PCR). result  In 75 patients with acute leptospirosis diagnosed by MAT (respectively, 90 patients diagnosed by MAT/PCR), the response in paired early and convalescent sera was positive in 78.9% (67.9%) by DSA, 76.0% (67.8%) by ELISA, 58.7% (55.6%) by IHA, 44.0% (53.3%) by PCR, and 100% (90.0%) by MAT. In early serum only, the response in patients diagnosed by MAT (respectively by MAT/PCR) was positive in 36.0% (38.9%) by DSA, 36.0% (37.8%) by ELISA, 14.7% (18.9%) by IHA, 39.2% (48.3%) by PCR, and 53.3% (58.9%) by MAT titre ≥1 : 100. DSA detected the main serogroups implicated in human leptospirosis in Seychelles and demonstrated sensitivity comparable to ELISA. In 124 single sera from control subjects without overt disease, the response was positive in 4.8% by DSA, 3.2% by ELISA, 3.2% by IHA, 13.8% by PCR, 37.9% by MAT titre ≥1 : 100, and 2.4% by MAT titre ≥1 : 800, giving evidence of the frequency of both past and current subclinical infection in Seychelles and that DSA was less sensitive than MAT to detect moderate levels of leptospiral antibodies. conclusion  DSA is a simple and reproducible assay well adapted to field conditions and could usefully contribute to the evaluation of leptospirosis in areas devoid of serological laboratory facilities.
Seroepidemiology of Helicobacter pylori infection in a Jamaican community
Authors: Lindo J. F. , Lyn‐Sue A. E. , Palmer C. J. , Lee M. G. , Vogel P. , Robinson R. D. 
Published: March 2003

Summary We researched epidemiologic associations between environmental and demographic factors and prevalence of Helicobacter pylori infection in a suburban Jamaican community. Using a clustered sampling technique, 22 domestic yards enclosing 60 separate households were randomly selected from a local community. All household members (n = 346) were invited to participate following informed consent; the overall compliance rate was 58.9%. A commercial enzyme immunoassay (HMáCAP) was used to detect IgG antibodies raised against H. pylori. Environmental and demographic information was obtained by questionnaire. The seroprevalence of H. pylori was 69.9% (n = 202). Analysis of the independent variables revealed three major components: Component 1 described, collectively, good personal hygiene and sanitation, indoor water supply and absence of straying animals in the peridomestic area; Component 2 included older age, good personal hygiene and large yard size; Component 3 the presence of domestic animals (cats and dogs) and, again, large yard size. These three complexes explained 42.2% of the variability in the data set. Logistic regression showed that Components 2 and 3 were independently associated with H. pylori seropositivity, indicating that a combination of demographic, environmental and zoonotic factors is involved in the spread of H. pylori infections at the tropical community level.
Microheterogeneity of serogroup A (subgroup III) Neisseria meningitidis during an outbreak in northern Ghana
Authors: Gagneux Sébastien , Hodgson Abraham , Ehrhard Ingrid , Morelli Giovanna , Genton Blaise , Smith Tom , Tanner Marcel , Binka Fred , Achtman Mark , Pluschke Gerd 
Published: March 2003

Summary During a meningitis outbreak in the eastern subdistrict of the Kassena‐Nankana District of the Upper East Region of Ghana, we analysed cerebrospinal fluid from suspected meningitis cases for the most common causative organisms. In 50 of 92 samples analysed, serogroup A Neisseria meningitidis were detected. The ages of serogroup A N. meningitidis patients ranged from 4 months to 64 years. The case fatality ratio was 20%. Coma or stupor on presentation worsened the prognosis. All serogroup A N. meningitidis isolates recovered revealed the A: 4: P1.9, 20 phenotype characteristic for the subgroup III clonal grouping. No evidence for resistance to penicillin G, chloramphenicol, cefotaxime, ciprofloxacin, rifampicin or tetracycline was found. All strains were resistant to sulphadiazine. Restriction analysis patterns of opa, iga and ingA genes were characteristic for the majority of N. meningitidis serogroup A subgroup III bacteria isolated in Africa after the 1987 epidemic in Mecca. Differences in pulsed‐field gel electrophoresis patterns of NheI and SpeI digested DNA revealed microheterogeneity among the Ghanaian isolates.
Inhibition of glutathione synthesis as a chemotherapeutic strategy for leishmaniasis
Authors: Kapoor Preeti , Sachdev Monika , Madhubala Rentala 
Published: March 2003

Summary This study focuses on the use of buthionine sulphoximine (BSO), a γ‐glutamylcysteine synthetase inhibitor, on Leishmania donovani growth. The effect of BSO on amastigote multiplication within macrophages showed that 5 m
m BSO decreased infectivity by about 50% and the mean number of amastigotes per 100 infected macrophages by 21%. The mechanism may be that BSO resulted in enhanced nitric oxide (NO) levels within macrophages, probably due to inhibition of GSH content since GSH (10 mm) given after BSO treatment led to a decrease in NO compared to macrophages treated with BSO alone which were preexposed to the Leishmania surface molecule lipophosphoglycan.
Growth and survival of low birthweight infants from 0 to 9 years in a rural area of Ghana. Comparison of moderately low (1501–2000 g) and very low birthweight (1000–1500 g) infants and a local reference population
Authors: van der Mei J. , Volmer M. , Boersma E. R. 
Published: March 2003

Summary This prospective and descriptive study was conducted to evaluate the growth and survival of 105 low birthweight (LBW, 1000–2000 g) infants discharged during a 4‐year period from Agogo Hospital, Ghana, and followed from birth until the age of 4–9 years. Thirty‐two babies were very low birthweight children (VLBW, 1000–1500 g) and 73 (70%) were of moderately low birthweight (MLBW, 1501–2000 g). At the age of 3 years, 15 children (14.2%) had not come for follow‐up; of the remaining 90 children, nine (10%) had died, five during the first 3 months of life. At follow‐up from 4 to 9 years of age, two more children could not be traced and another two had died. Compared to a local reference population and the WHO standard, growth of survivors lagged behind and caught up only slightly during the first 3 years of life. From 3 to 9 years of age, median growth impairment increased, which either suggests impaired growth potential or poor health and inadequate nutrition. This long‐term study confirms that LBW (1000–2000 g) infants, particularly VLBW children, are at high risk.
Use of the recombinant Onchocerca volvulus protein Ov20/OvS1 for the immunodiagnostic differentiation between onchocerciasis and mansonelliasis and for the characterization of hyperreactive onchocerciasis (sowda)
Authors: Mpagi J. L. , Büttner D. W. , Tischendorf F. W. , Erttmann K. D. , Brattig N. W. 
Published: March 2003

Summary The protein Ov20/OvS1 was used as antigen in ELISA and Western blot in order to differentiate onchocerciasis from African mansonelliasis and to characterize the hyperreactive form of Onchocerca volvulus infection (sowda). The specificity of the IgG4 Western blot was 98% for the differentiation between persons with onchocerciasis and Mansonella microfilariae (mf) carriers (125 persons with M. perstans and 92 with M. streptocerca), whereas the IgG4 ELISA showed a specificity of 81% in 137 M. perstans mf carriers and 85% in 94 M. streptocerca mf carriers. The sensitivity of Ov20/OvS1 in identifying onchocerciasis using the IgG4 ELISA was 75% for 103 O. volvulus mf carriers with the generalized and 89% for 44 patients with the sowda form of onchocerciasis. IgE antibodies against OvS1 were found in 95% of 39 patients with hyperreactive onchocerciasis but only in 15% of 47 persons with the generalized form. Thus, Ov20/–OvS1 appears a promising candidate antigen for the diagnosis of onchocerciasis and in particular for the detection of the sowda type of disease.