bluuebunny/crossref_metadata_2025_split huggingface dataset:
Touch modulates gravity sensing to regulate the growth of primary roots of Arabidopsis thaliana
Authors: Massa Gioia D. , Gilroy Simon 
Published: March 2003

SummaryPlants must sense and respond to diverse stimuli to optimize the architecture of their root system for water and nutrient scavenging and anchorage. We have therefore analyzed how information from two of these stimuli, touch and gravity, are integrated to direct root growth. In Arabidopsis thaliana, touch stimulation provided by a glass barrier placed across the direction of growth caused the root to form a step‐like growth habit with bends forming in the central and later the distal elongation zones. This response led to the main root axis growing parallel to, but not touching the obstacle, whilst the root cap maintained contact with the barrier. Removal of the graviperceptive columella cells of the root cap using laser ablation reduced the bending response of the distal elongation zone. Similarly, although the roots of the gravisensing impaired pgm1–1 mutant grew along the barrier at the same average angle as wild‐type, this angle became more variable with time. These observations imply a constant gravitropic re‐setting of the root tip response to touch stimulation from the barrier. In wild‐type plants, transient touch stimulation of root cap cells, but not other regions of the root, inhibited both subsequent gravitropic growth and amyloplast sedimentation in the columella. Taken together, these results suggest that the cells of the root cap sense touch stimuli and their subsequent signaling acts on the columella cells to modulate their graviresponse. This interaction of touch and gravity signaling would then direct root growth to avoid obstacles in the soil while generally maintaining downward growth.
GFP‐tagging of cell components reveals the dynamics of subcellular re‐organization in response to infection of Arabidopsis by oomycete pathogens
Authors: Takemoto Daigo , Jones David A. , Hardham Adrienne R. 
Published: March 2003

SummaryCytoplasmic aggregation, the rapid translocation of cytoplasm and subcellular components to the site of pathogen penetration, is one of the earliest reactions of plant cells against attack by microorganisms. We have investigated cytoplasmic aggregation during Arabidopsis–oomycete interactions. Infection by non‐pathogenic Phytophthora sojae was prevented in the plant epidermal cell layer, whereas Peronospora parasitica isolates Cala2 (avirulent) and Noks1 (virulent) could both penetrate into the mesophyll cell layer. Epidermal cell responses to penetration by these oomycetes were examined cytologically with a range of transgenic Arabidopsis plants expressing Green Fluorescent Protein (GFP)‐tagged cell components. These included plants containing GFP‐TUA6 for visualizing microtubules, GFP‐hTalin for actin microfilaments, GFP‐tm‐KKXX for endoplasmic reticulum (ER), and STtmd‐GFP for the Golgi apparatus. In all interactions, actin microfilaments were actively re‐arranged and formed large bundles in cytoplasmic strands focused on the penetration site. Aggregation of ER membrane and accumulation of Golgi bodies at the infection site were observed, suggesting that production and secretion of plant materials were activated around the penetration site. Microtubules did not become focused on the penetration site. No difference was evident between the responses of epidermal cells in the non‐host, incompatible and compatible interactions. This result indicates that the induction of cytoplasmic aggregation in Arabidopsis epidermal cells was neither suppressed by the virulent strain of Peronospora, nor effective in stopping infection.
Determination of red cell volume in infants needing blood transfusion
Authors: Fisher  , Matthes  , Wynn  , Al‐Ismail  , Hoy  , Wardrop  , Williams  
Published: March 2003

The total circulating red cell volume (RCV) is a better guide to the oxygen‐carrying capacity of the blood in the whole circulation than is the haemoglobin concentration (Hb) or haematocrit in a blood sample. Pre‐ and post‐transfusion RCV (and blood volume (BV)) may be determined by flow cytometry by exploiting antigen differences between transfused donor red cells and the recipient's red cells. This paper describes the use of red cell antigen differences of Duffy, Kidd, MN and RhD between donor and recipient.In 20 infants, transfused on 21 occasions, pretransfusion RCV ranged from 12 to 39 mL kg−1 body weight. Only at one transfusion could no usable donor–recipient antigen differences be exploited.Measurement of RCV, used routinely, may determine the transfusion requirements of sick infants more accurately, with the aim of normalizing RCV and BV — securing euvolaemia — at the end of the transfusion. This may allow a complete correction of the RCV deficiency at the first occasion of transfusion. This approach may reduce donor exposures and also optimize oxygen transport and organ perfusion of the infant undergoing intensive management, perhaps leading ultimately to improved survival rates and fewer long‐term complications of neonatal intensive care.
Anti‐HNA‐1a antibodies detected in a FcγRIIIb ‘null’ male blood donor
Authors: Lucas G. F. , Evans R. G. , Griffiths R. E. , Rogers S. E. 
Published: March 2003

FcγRIIIb ‘null’ individuals do not express the HNA‐1a, ‐1b & ‐1c alloantigens and the reported incidence of this condition in the Caucasian population is between 1 in 1000 and 2000. The majority of FcγRIIIb ‘null’ individuals have been identified following the investigation of neonatal alloimmune neutropenia due to maternally transferred anti‐FcγRIIIb antibodies.This report describes a healthy, male blood donor who was screened for the presence of granulocyte‐specific antibodies as part of a foetal concentration donor accreditation programme. The donor's serum was found to contain anti‐HNA‐1a IgM (and weak IgG) antibodies using an immunofluorescence test. Anti‐lymphocyte antibodies were not detected. Further investigation was undertaken to determine whether the antibodies were alloimmune or autoimmune in origin. Granulocyte membrane bound IgG and IgM was within the normal range and the granulocytes were unreactive both with monoclonal FcRIIIb and HNA‐1a antibodies in immunofluorescence tests. HNA‐1a and HNA‐1b PCR products could not be amplified from the donor's genomic DNA using an SSP technique. It was concluded that the donor was FcγRIIIb ‘null’. The donor denied any history of blood transfusion or surgical procedures; nor was there any evidence of such procedures in early life. This suggests either that HNA‐1a antibodies may, in some circumstances, be ‘naturally occurring’ or that the antibodies detected may be part of an autoimmune response to ‘HNA‐1a like’ structures on other tissues. This is the first time that anti‐HNA‐1a antibodies have been reported in an FcγRIIIb ‘null’ individual.There was no history of transfusion reactions associated with the use of the donor's blood products. However, the donor was withdrawn from the donor panel because HNA‐1a IgM antibodies have been implicated in Transfusion Related Acute Lung Injury.
On investigation of markers that may influence alloantibody responses to HPA‐1a
Authors: Railton D. , Brown J. , Brown C. , Williamson L. M. , Navarrete C. 
Published: March 2003

In > 99% of cases, HPA‐1a antibody production during pregnancy is associated with maternal DRB3*0101 positivity. However, only 35% of HPA‐1a neg/DRB3*0101 women produce antibodies (Ab). This study attempted to identify additional genetic marker(s) that may better predict anti‐HPA‐1a production in these women.Seventy‐eight DRB3*0101 pos HPA‐1a neg, women (40 HPA‐1a Ab pos, 38 Ab neg) with HPA‐1a pos infants, were typed for HLA‐DRB1*, ‐B3*, ‐B4*, ‐B5*. Results were compared with those from 83 DRB3*0101 pos normal donors. SNaPshot™ was used to test for a polymorphism of the TNF‐α locus.The frequency of DRB1*15 was significantly lower in Ab pos mothers (1/40) compared to controls (16/83; P = 0·03), but not compared to Ab neg mothers (6/38; P = 0·07). DRB1*12 was found only in Ab neg mothers (5/38) (controls 0/83; P = 0·02). A study of TNF‐α genotype (n = 30, Ab pos; Ab neg; controls) found no difference between the mothers' groups, or mothers and controls.Presence of DRB1*15 or DRB1*12 may lower the likelihood of HPA‐1a Ab production. Raised frequency of DRB4* was seen in mothers with affected neonates (13/22) (unaffected, Ab pos 3/11; P = 0·02). DRB4* may increase the odds of HPA‐1a alloimmunization. Three NAITP cases due to anti‐HPA‐1a have been reported (2 local, 1 published), involving mothers DRB3*0101 neg, but DRB4* pos. TNF‐α genotype may not predict anti‐HPA‐1a production in these women. Studies with larger groups would establish the value of these markers in defining women at high risk of HPA‐1a alloimmunization.
Accelerated autoantibody clearance by IVIG therapy
Authors: Bleeker W. K. , Teeling J. L. , Hack C. E. 
Published: March 2003

Recently, it has been postulated that the beneficial effect of intravenous immunoglobulins (IVIG) in antibody‐mediated autoimmune disorders is based on an accelerated catabolism of autoantibodies due to saturation of FcRn. In the present study, we determined the magnitude and time course of this effect in a computer simulation to see whether this mechanism may indeed explain clinical observations.A pharmacokinetic model for IgG clearance was established in which concentration changes were calculated in small time steps. To validate the model we performed in vivo experiments with mice. A computational simulation accurately predicted the magnitude of the observed in vivo effect of IVIG administration on endogenous IgG levels.For human patients our model predicted a gradual decrease in autoantibody levels after IVIG administration (2 g/kg) with a maximum reduction of about 25% after 3–4 weeks and a duration of several months. This corresponds well to the effects of IVIG therapy observed in two patient studies: one on calcium‐channel autoantibodies by Bain et al. (Neurology 1996; 47: 678–683) and another on ANCA by Jayne et al. (J Autoimmunity 1993; 6: 207–219).In conclusion, accelerated IgG clearance can explain a modest decrease in autoantibody levels observed in several patient studies. However, in some other clinical studies larger or more rapid effects have been observed, which can not be explained by accelerated clearance, suggesting that IVIG can also reduce autoantibody levels via other mechanisms such as down‐regulation of antibody production or neutralization by anti‐idiotypic antibodies.
The FcγRIIIA‐158V allele is a risk factor for ITP
Authors: De Haas M. , Osborne J. , Kleijer M. , Von Dem Borne A. E. G. KR. , Bussel J. 
Published: March 2003

In those patients with idiopatic thrombocytopenic purpura (ITP) that do not respond to standard therapy with corticosteroids and/or splenectomy, high‐dose intravenous IgG or low dose anti‐D is given to achieve transient increases in circulating platelet counts. The effect of these treatments is thought to be blockade of macrophage Fc receptors. Macrophages express FcγRIa, FcγRIIa and FcγRIIIa, all three classes may be involved in binding and phagocytosis of sensitized platelets. The FcγRIIa‐131R/H and FcγRIIIa‐158V/F polymorphisms influence the IgG‐binding affinity of the receptors. In literature, skewing of distribution of the FcγRIIA alleles towards the low‐affinity‐genotype: FcγRIIA‐131R/R has been described in ITP patients. Others did not confirm these findings.We genotyped a group of 83 patients with chronic ITP and 87 ethnically comparable hospital controls for the FcγRIIA, FcγRIIIA and FcγRIIIB polymorphisms, the latter Fc receptor is only expressed by neutrophils.In the ITP patient population, the gene frequency of the FcγRIIIA‐158V allele was 0·55, vs. 0·43 in the control population (P = 0·001). The genotype distribution of the FcγRIIIA‐V/F polymorphism was also significantly different from that of a control population (P = 0·006). The allele and genotype distributions of the FcγRIIA‐131R/H or the FcγRIIIB‐NA1,2 polymorphisms was similar in patients and controls.Our observations show that macrophage FcãRIIIa may be the most important receptor in clearance of sensitized platelets, or that FcγRIIIa‐bearing cells (NK cells or macrophages) are implicated in the pathogenesis of this autoimmune disease.
Platelet antibodies in transfused patients
Authors: Kiefel V. , König C. , Kroll H. , Santoso S. 
Published: March 2003

P atients and M
ethods  We studied sera of 252 patients with haematological or oncological diseases, who received multiple transfusions of rbc and/or platelet concentrates. The aim of our study was to analyse the specificity of platelet reactive antibodies (platelet specific and HLA‐antibodies) in a large series of transfused patients. All sera were analysed by platelet immunofluorescence, platelet agglutination, MAIPA and the lymphocytotoxic test (LCT).R esults Platelet reactive antibodies were detected in 113 patients. Among female patients with previous pregnancies 21/36 were alloimmunized but only 7/30 female patients who had not been pregnant (P = 0·0049). In 108 (42·9%) of all sera, we found HLA‐specific antibodies. In a subset of 40 sera, reactions of HLA class I antibodies were compared with an identical cell panel using LCT and MAIPA assay. Twenty‐nine of these sera showed discrepant results in both techniques. Sera from 20 patients contained platelet specific alloantibodies with defined specificity: HPA‐5b (10), HPA‐1b (4), HPA‐5a (2) HPA‐1a (1), HPA‐2b (1), HPA‐5b + HPA‐1b (1), HPA‐1b + HPA‐2b (1). All sera with anti‐HPA‐1b contained additional HLA antibodies, 4 sera with anti‐HPA‐5b apparently contained no HLA‐antibodies. Ten sera contained ‘panreactive’ antibodies with broad specificity: GP IIb/IIIa (4), GP IIb/IIIa + Ia/IIa (2), GPIIb/IIIa + Ib/IX (1), GP IIb/IIIa + Ia/IIa + Ib/IX (3).C onclusion (1) Platelet alloantibody specificities in transfused patients (predominantly anti‐HPA‐5b and − 1b) differ significantly from those observed in neonatal alloimmune thrombocytopenia and post‐transfusion purpura, where anti‐HPA‐1a is the most prevalent specificity. (2) Results for detection of HLA‐antibodies differ considerably in relation to serological technique and target cells.
The frequency of anti‐C + anti‐G in the absence of anti‐D in alloimmunized pregnancies
Authors: Palfi M. , Gunnarsson C. 
Published: March 2003

. Anti‐D+C are often initially identified in sera from alloimmunized women. Anti‐G may be present in these samples, mimicking anti‐D+C, and therefore the differentiation of anti‐D, ‐C and ‐G may be important.Sera from 27 alloimmunized women, initially identified as containing anti‐D + anti‐C, were analysed by adsorption/elution studies in the presence of polyethylene glycol (PEG) using R0r (D+C–G+) and r'r(D–C+G+) red blood cells (RBC). Additionally, 15/27 samples were tested by adsorption in the presence of PEG and subsequently warm elution, using rGr (D–C–G+) RBC. Anti‐G + anti‐C, without anti‐D, were identified in 4/27 samples (14·8%) and none of the newborn children needed postpartum treatment. The combination of D+G, D+C and D+C+G antibodies occurred in 25·9%, 11·1% and 48·1% of the women, respectively. Overall, anti‐G was detected in 24/27 samples (88·9%). Pregnant women shown to have anti‐G+C but not anti‐D should receive Rh immune globulin. Additionally, the finding of apparent anti‐D+C during pregnancy in D‐negative spouses may lead to paternity testing and therefore a correct antibody identification is necessary.
ABO‐incompatibility in solid organ transplantation
Authors: Rydberg L. 
Published: March 2003

. The most important transplantation antigen system in solid organ transplantation is the ABO histo‐blood group system. Crossing the ABO barrier in solid organ transplantation is usually not done except for emergency liver transplantations. Early experiences of crossing the ABO barrier in renal transplantation were very disappointing. In the 1970s, clinical trials were started transplanting kidneys of subgroup A2 into blood group O recipients. The tissues of the A2 subgroup expresses reduced amount of A antigens compared to subgroup A1 and the recipients had no special pretreatment and standard immunosuppression. A number of early graft losses were experienced but the trial also resulted in several long time surviving grafts. A few centres have adapted the concept of A2 to non A kidney transplantations with successful results, when the recipient anti‐A titres are low or reduced prior to transplantation.In the early 1980s one group successfully transplanted A1 and B kidneys from living related donors across the ABO‐barrier using an immunosuppressive protocol consisting of quadruple drugs and splenectomy and this protocol was adapted by a few other groups. In Japan, where cadaver donors are available in very limited number, the largest number of ABO‐incompatible transplantations have been performed. Altogether more than 300 ABO‐incompatible kidney transplantations have been performed in more than 40 centres since 1989.ABO‐incompatible liver transplantations have been performed mainly in emergency cases and the results have generally been inferior to ABO‐compatible grafts. In children below the age of three years, liver transplantations across the ABO‐barrier have been quite successful especially with living related donors. Very few ABO‐incompatible heart/heart–lung/lung‐transplantations have been reported with a few successful cases, but the majority have been failures. Recently a series of ABO‐incompatible heart transplants performed in small children have been reported with a high success rate.
The United Kingdom National External Quality Assessment Scheme (Blood Transfusion Laboratory Practice): trends in proficiency and practice between 1985 and 2000
Authors: Knowles S. M. , Milkins C. E. , Chapman J. F. , Scott M. 
Published: March 2003

Summary Proficiency in blood transfusion laboratory practice has improved over the last 15 years (1985–2000). Error rates for ABO grouping have fallen from 0·19 to 0·02% (P = 0·003). A similar trend is evident for antibody screening, with error rates for false negative antibody screens falling from 3·2 to 0·5% (P < 0·001), and for antibody identification, for sera containing a single alloantibody, with error rates falling from 8·8% to 0·9% over the last 10 years (P < 0·001). Proficiency in serological crossmatching to detect clinically significant non‐ABO incompatibilities (other than Kidd), has also improved (P < 0·001). However, error rates for RhD grouping have not changed and there has been a recent decline in proficiency in detecting weak ABO incompatibilities and Kidd antibodies with heterozygous cells.Procedures for pretransfusion testing have also been rationalized over this time. The indirect antiglobulin test (IAT) is used in isolation by 73% of laboratories for antibody screening, and 10% rely on the direct room temperature (DRT), immediate spin (IS) crossmatch in the absence (current and/or historical) of clinically significant antibodies.Despite the improvements in error rates that have occurred alongside the rationalizations, there is still evidence of noncompliance with current published BCSH guidelines and manufacturers' instructions.
Isolate resistance of Blastocystis hominis to metronidazole
Authors: Haresh K. , Suresh K. , Anuar A. Khairul , Saminathan S. 
Published: March 2003

Summary Isolates of Blastocystis hominis from infected immigrant workers from Indonesia, Bangladesh and infected individuals from Singapore and Malaysia were assessed for growth pattern and degree of resistance to different concentrations of metronidazole. Viability of the cells was assessed using eosin‐brilliant cresyl blue which stained viable cells green and nonviable cells red. The Bangladeshi and Singaporean isolates were nonviable even at the lowest concentration of metronidazole at 0.01 mg/ml. The parasites of the Malaysian isolate were resistant to a concentration of 0.01 mg/ml, whereas 40% of the initial inoculum of parasites from the Indonesian isolate at day one were still viable in cultures with 1.0 mg/ml metronidazole. The study shows that isolates of B. hominis of different geographical origin have different levels of resistance to metronidazole. The search for more effective drugs to eliminate the parasite appears inevitable, especially since surviving parasites from metronidazole cultures show greater ability to multiply in subcultures than controls.
Screening of army soldiers for Wuchereria bancrofti infection in the metropolitan Recife region, Brazil: implications for epidemiological surveillance
Authors: Medeiros Zulma , Gomes Judilson , Béliz Fátima , Coutinho Amaury , Dreyer Patricia , Dreyer Gerusa 
Published: March 2003

SummaryBetween 1989 and 1995, blood surveys were performed for Wuchereria bancrofti infection in several barracks of the Brazilian army in the metropolitan Recife region. For initial screening, 60 μl of capillary blood were examined for microfilaria. All men who tested positive had microfilaria quantified by filtration of venous blood through a polycarbonate membrane. Of 23773 men screened, 585 (2.5%) had microfilaria (mf). Microfilarial density ranged from < 1–8706 mf/ml of blood. Thirteen individuals had ultra‐low microfilarial densities (1 mf/11 ml of blood). Characterization of 174 autochthonous cases made it possible to map 8 new districts in 4 cities within metropolitan Recife region where transmission of W. bancrofti was previously unknown. Routine screening of soldiers in the military may provide important surveillance data for national programmes to eliminate transmission of W. bancrofti.
Rift valley fever surveillance in the lower Senegal river basin: update 10 years after the epidemic
Authors: Thonnon Jocelyn , Picquet Michel , Thiongane Yaya , Lo Mustapha , Sylla Roughy , Vercruysse Jozef 
Published: March 2003

Summary After the Rift valley fever (RVF) epidemic of 1987 in the Senegal River Basin, RVF surveillance based on serosurveys has been conducted for 10 years. Serum samples were obtained from 1336 persons and from sheep and goats in selected areas, and these were tested for IgG/IgM RVF antibodies by ELISA. After a period of regular decrease in RVF prevalence in domestic animals until 1993, an epizootic was observed in all herds in 1994–95 with increases in IgM levels and abortions. During the same period, no human cases or RVF IgM were detected. The RVF IgG prevalence significantly correlated with date of birth: children born after 1987 have a low prevalence (5%) in clear contrast to the older population (25.3%) in Podor district. A retrospective analysis of rainfall and RVF prevalence in small domestic animals over the last 10 years showed that the re‐emergence correlated with heavy rainfall. A general analysis of the risk of re‐emergence and the efficiency of this RVF surveillance system are presented.
Strategies to enhance the use of health systems research for health sector reform
Authors: Sauerborn R. , Nitayarumphong S. , Gerhardus A. 
Published: March 2003

Summary In spite of frequent claims to the contrary, there is very little evidence that health systems research actually influences policy‐making. Based on a case study from Thailand and a literature review, we develop a stakeholder‐oriented model of policy‐making. We argue that only if stakeholders' needs are taken into consideration during design and implementation of scientific projects and dissemination of the results, research will have a chance to influence the policy process. From this model, we derive a five‐step approach to enhance the use of research by various stakeholders. We then propose institutional arrangements and conditions to make the use of research for policy‐making more sustainable.  'The world of ideas and the world of action are not separate, but inseparable parts of each other. Ideas are true forces that change the tangible world. The man and woman of action has no less responsibility to understand the world than the scholar'. Donabedian (1986)