bluuebunny/crossref_metadata_2025 huggingface dataset:
Double antisense plants lacking ascorbate peroxidase and catalase are less sensitive to oxidative stress than single antisense plants lacking ascorbate peroxidase or catalase
Authors: Rizhsky Ludmila , Hallak‐Herr Elza , Van Breusegem Frank , Rachmilevitch Shimon , Barr Jason E. , Rodermel Steven , Inzé Dirk , Mittler Ron
Published: March 2003

The plant genome is a highly redundant and dynamic genome. Here, we show that double antisense plants lacking the two major hydrogen peroxide‐detoxifying enzymes, ascorbate peroxidase (APX) and catalase (CAT), activate an alternative/redundant defense mechanism that compensates for the lack of APX and CAT. A similar mechanism was not activated in single antisense plants that lacked APX or CAT, paradoxically rendering these plants more sensitive to oxidative stress compared to double antisense plants. The reduced susceptibility of double antisense plants to oxidative stress correlated with suppressed photosynthetic activity, the induction of metabolic genes belonging to the pentose phosphate pathway, the induction of monodehydroascorbate reductase, and the induction of IMMUTANS, a chloroplastic homologue of mitochondrial alternative oxidase. Our results suggest that a co‐ordinated induction of metabolic and defense genes, coupled with the suppression of photosynthetic activity, can compensate for the lack of APX and CAT. In addition, our findings demonstrate that the plant genome has a high degree of plasticity and will respond differently to different stressful conditions, namely, lack of APX, lack of CAT, or lack of both APX and CAT.
The Nod factor‐elicited annexin MtAnn1 is preferentially localised at the nuclear periphery in symbiotically activated root tissues of Medicago truncatula
Authors: De Carvalho‐Niebel Fernanda , Timmers Antonius C. J. , Chabaud Mireille , Defaux‐Petras Annie , Barker David G.
Published: March 2003

The Medicago truncatula MtAnn1 gene, encoding a putative annexin, is transcriptionally activated in root tissues in response to rhizobial Nod factors. To gain further insight into MtAnn1 function during the early stages of nodulation, we have examined in detail both spatio‐temporal gene expression patterns and MtAnn1 activity and localisation in root tissues. Analysis of transgenic Medicago plants expressing a pMtAnn1‐GUS fusion has revealed a novel pattern of transcription in both outer and inner cell layers of the root following either Nod factor‐treatment or rhizobial inoculation. The highest gene expression levels were observed in the endodermis and outer cortex. These transgenic plants also revealed that MtAnn1 expression is associated with lateral root development and cell differentiation in the root apex independent of nodulation. By purifying recombinant MtAnn1 we were able to demonstrate that this plant annexin indeed possesses the calcium‐dependent binding to acidic phospholipids typical of the annexin family. Antisera against recombinant MtAnn1 were then used to show that tissue‐specific localisation of the MtAnn1 protein in Medicago roots matches the pMtAnn1‐GUS expression pattern. Finally, both immunolabelling and in vivo studies using MtAnn1‐GFP reporter fusions have revealed that MtAnn1 is cytosolic and in particular localises to the nuclear periphery in cortical cells activated during the early stages of nodulation. In the light of our findings, we discuss the possible role of this annexin in root tissues responding to symbiotic rhizobial signals.
ABI5 acts downstream of ABI3 to execute an ABA‐dependent growth arrest during germination
Authors: Lopez‐Molina Luis , Mongrand Sébastien , McLachlin Derek T. , Chait Brian T. , Chua Nam‐Hai
Published: March 2003

The development of a germinating embryo into an autotrophic seedling is arrested under conditions of water deficit. This ABA‐mediated developmental checkpoint requires the bZIP transcription factor ABI5. Here, we used abi3‐1, which is also unable to execute this checkpoint, to investigate the relative role of ABI3 and ABI5 in this process. In wild‐type Arabidopsis plants, ABI3 expression and activity parallel those described for ABI5 following stratification. During this process, transcript levels of late embryogenesis genes such as AtEm1 and AtEm6 are also re‐induced, which might be responsible for the acquired osmotic tolerance in germinated embryos whose growth is arrested. ABI5 expression is greatly reduced in abi3‐1 mutants, which has low AtEm1 or AtEm6 expression. Cross complementation experiments showed that 35S‐ABI5 could complement abi3‐1, whereas 35S‐ABI3 cannot complement abi5‐4. These results indicate that ABI5 acts downstream of ABI3 to reactivate late embryogenesis programmes and to arrest growth of germinating embryos. Although ABI5 is consistently located in the nucleus, chromosomal immunoprecipitation (ChIP) experiments revealed that ABA increases ABI5 occupancy on the AtEm6 promoter.
Down‐regulation of DR12, an auxin‐response‐factor homolog, in the tomato results in a pleiotropic phenotype including dark green and blotchy ripening fruit
Authors: Jones Brian , Frasse Pierre , Olmos Enrique , Zegzouti Hicham , Li Zheng Guo , Latché Alain , Pech Jean Claude , Bouzayen Mondher
Published: March 2003

Following differential screening of gene expression during tomato fruit development, we isolated developmentally regulated (DR) clones, including several putative transcription factors. Based on sequence homology, DR1, DR3, DR4 and DR8 are members of the Aux/IAA family, and DR12 belongs to the auxin response factor (ARF) family of transcription factors. Importantly, mRNA accumulation for the Aux/IAA‐like genes was regulated by ethylene in tomato fruit but not in the leaves, indicating that these putative auxin response components also participate to the ethylene‐dependent regulation of gene expression in a tissue‐specific manner. The functional significance of DR12, the ARF‐like gene, was investigated by cellular biology and reverse genetics approaches. Heterologous protein targeting studies, carried out using a DR12–GFP gene fusion construct, revealed specific nuclear localization of the DR12‐encoded protein, in accordance with its putative function as a transcriptional regulator. Transgenic plants over‐ and under‐expressing DR12 were generated in order to explore the physiological role of the gene. Both antisense and sense co‐suppressed DR12‐inhibited lines displayed a pleiotropic phenotype that included dark‐green immature fruit, unusual cell division in the fruit pericarp, blotchy ripening, enhanced fruit firmness, upward curling leaves and increased hypocotyl and cotyledon growth. While a perturbation of the response to auxin may explain some of the phenotypes, surprisingly, the expression of members of four classes of early auxin‐regulated genes was unaffected in the DR12‐inhibited plants. The involvement of this ARF‐like encoded protein in mediating the auxin response is discussed along with the possibility that it might affect responsiveness to other phytohormones in the tomato.
Parallel recordings of photosynthetic electron transport and K+‐channel activity in single guard cells
Authors: Goh Chang‐Hyo , Dietrich Petra , Steinmeyer Ralf , Schreiber Ulrich , Nam Hong‐Gil , Hedrich Rainer
Published: March 2003

Stomata open in response to red and blue light. Red light‐induced stomatal movement is mediated by guard cell chloroplasts and related to K+‐uptake into these motor cells. We have combined a new type of microchlorophyll fluorometer with the patch–clamp technique for parallel studies of the photosynthetic electron transport and activity of plasma membrane K+ channels in single guard cell protoplast. In the whole‐cell configuration and presence of ATP in the patch‐pipette, the activity of the K+‐uptake channels remained constant throughout the course of an experiment (up to 30 min) while photosynthetic activity declined to about 50%. In the absence of ATP inward K+ currents declined in a time‐dependent manner. Under these ATP‐free conditions, photosynthetic electron transport was completely blocked within 8 min. ADP together with orthophosphate was able to prevent inhibition of photosynthetic electron transport and run‐down of K+‐channel activity. The results demonstrate that the combination of these two techniques is suited to directly study cytosolic factors as common regulators of photosynthesis and plasma membrane transport within a single‐cell.
The Arabidopsis eukaryotic initiation factor (iso)4E is dispensable for plant growth but required for susceptibility to potyviruses
Authors: Duprat Anne , Caranta Carole , Revers Frédéric , Menand Benoît , Browning Karen S. , Robaglia Christophe
Published: March 2003

An Arabidopsis thaliana line bearing a transposon insertion in the gene coding for the isozyme form of the plant‐specific cap‐binding protein, eukaryotic initiation factor (iso) 4E (eIF (iso) 4E), has been isolated. This mutant line completely lacks both eIF(iso)4E mRNA and protein, but was found to have a phenotype and fertility indistinguishable from wild‐type plants under standard laboratory conditions. In contrast, the amount of the related eIF4E protein was found to increase in seedling extracts. Furthermore, polysome analysis shows that the mRNA encoding eIF4E was being translated at increased levels. Given the known interaction between cap‐binding proteins and potyviral genome‐linked proteins (VPg), this plant line was challenged with two potyviruses, Turnip mosaic virus (TuMV) and Lettuce mosaic virus (LMV) and was found resistant to both, but not to the Nepovirus, Tomato black ring virus (TBRV) and the Cucumovirus, Cucumber mosaic virus (CMV). Together with previous data showing that the VPg–eIF4E interaction is necessary for virus infectivity and upregulates genome amplification, this shows that the eIF4E proteins are specifically recruited for the replication cycle of potyviruses.
The HAT2 gene, a member of the HD‐Zip gene family, isolated as an auxin inducible gene by DNA microarray screening, affects auxin response in Arabidopsis
Authors: Sawa Shinichiro , Ohgishi Maki , Goda Hideki , Higuchi Kanako , Shimada Yukihisa , Yoshida Shigeo , Koshiba Tomokazu
Published: March 2003

The plant hormone, auxin, regulates many aspects of growth and development. Despite its importance, the molecular mechanisms underlying the action of auxin are largely unknown. To gain a more comprehensive understanding of the primary responses to auxin, we analyzed the expression of genes in Arabidopsis seedlings treated with indole‐3‐acetic acid (IAA) for 15 min. We identified a single gene that is downregulated early, and 29 genes that are upregulated early. Several types of typical transcription factors are identified as early upregulated genes, suggesting that auxin signals are mediated by a master set of diverse transcriptional regulators. Of the genes that responded to auxin, the expression of the homeobox gene, HAT2, was induced rapidly. Furthermore, we show that the expression of HAT2 is induced by auxin, but not by other phytohormones. To analyze the function of HAT2 in the plant's response to auxin, we generated 35S::HAT2 transgenic plants. These produced long hypocotyls, epinastic cotyledons, long petioles, and small leaves, which are characteristic of the phenotypes of the auxin‐overproducing mutants, superroot1 (sur1) and superroot2 (sur2). On the other hand, 35S::HAT2 plants showed reduced lateral root elongation, and reduced auxin sensitivity compared to wild‐type plants. Together with the results of RNA blotting and biochemical analyses, these findings suggest that HAT2 plays opposite roles in the shoot and root tissues in regulating auxin‐mediated morphogenesis.
Cloning and functional expression of alkaline α‐galactosidase from melon fruit: similarity to plant SIP proteins uncovers a novel family of plant glycosyl hydrolases
Authors: Carmi Nir , Zhang Genfa , Petreikov Marina , Gao Zhifang , Eyal Yoram , Granot David , Schaffer Arthur A.
Published: March 2003

Raffinose and stachyose are ubiquitous galactosyl‐sucrose oligosaccharides in the plant kingdom which play major roles, second only to sucrose, in photoassimilate translocation and seed carbohydrate storage. These sugars are initially metabolised by α‐galactosidases (α‐gal). We report the cloning and functional expression of the first genes, CmAGA1 and CmAGA2, encoding for plant α‐gals with alkaline pH optima from melon fruit (Cucumis melo L.), a raffinose and stachyose translocating species. The alkaline α‐gal genes show very high sequence homology with a family of undefined ‘seed imbibition proteins’ (SIPs) which are present in a wide range of plant families. In order to confirm the function of SIP proteins, a representative SIP gene, from tomato, was expressed and shown to have alkaline α‐gal activity. Phylogenetic analysis based on amino acid sequences shows that the family of alkaline α‐gals shares little homology with the known prokaryotic and eukaryotic α‐gals of glycosyl hydrolase families 27 and 36, with the exception of two cross‐family conserved sequences containing aspartates which probably function in the catalytic step. This previously uncharacterised, plant‐specific α‐gal family of glycosyl hydrolases, with optimal activity at neutral‐alkaline pH likely functions in key processes of galactosyl‐oligosaccharide metabolism, such as during seed germination and translocation of RFO photosynthate.
Allene oxide cyclase dependence of the wound response and vascular bundle‐specific generation of jasmonates in tomato – amplification in wound signalling
Authors: Stenzel Irene , Hause Bettina , Maucher Helmut , Pitzschke Andrea , Miersch Otto , Ziegler Jörg , Ryan Clarence A. , Wasternack Claus
Published: March 2003

The allene oxide cyclase (AOC)‐catalyzed step in jasmonate (JA) biosynthesis is important in the wound response of tomato. As shown by treatments with systemin and its inactive analog, and by analysis of 35S::prosysteminsense and 35S::prosysteminantisense plants, the AOC seems to be activated by systemin (and JA) leading to elevated formation of JA. Data are presented on the local wound response following activation of AOC and generation of JA, both in vascular bundles. The tissue‐specific occurrence of AOC protein and generation of JA is kept upon wounding or other stresses, but is compromised in 35S::AOCsense plants, whereas 35S::AOCantisense plants exhibited residual AOC expression, a less than 10% rise in JA, and no detectable expression of wound response genes. The (i) activation of systemin‐dependent AOC and JA biosynthesis occurring only upon substrate generation, (ii) the tissue‐specific occurrence of AOC in vascular bundles, where the prosystemin gene is expressed, and (iii) the tissue‐specific generation of JA suggest an amplification in the wound response of tomato leaves allowing local and rapid defense responses.
AtBXL1, a novel higher plant (Arabidopsis thaliana) putative beta‐xylosidase gene, is involved in secondary cell wall metabolism and plant development
Authors: Goujon Thomas , Minic Zoran , El Amrani Abdelhak , Lerouxel Olivier , Aletti Estelle , Lapierre Catherine , Joseleau Jean‐Paul , Jouanin Lise
Published: March 2003

To investigate mechanisms involved in cell wall development, an Arabidopsis T‐DNA insertion mutant collection was screened to identify mutants with beta‐glucuronidase fusion gene expression in tissues undergoing secondary cell wall thickening. This promoter‐trapping strategy allowed the isolation of a transformant containing the GUS coding sequence inserted 700 bp upstream of the ATG of a putative beta‐xylosidase gene. The transformant has no phenotype as the expression of the gene was not disrupted by the insertion. The analysis of the predicted protein, AtBXL1, suggests its targeting to the extracellular matrix and its involvement in cell wall metabolism through a putative activity towards xylans. The 2‐kb promoter sequence of AtBXL1 was fused to the GUS coding sequence and introduced into wild‐type Arabidopsis thaliana. GUS expression was shown to be restricted to tissues undergoing secondary cell wall formation. Beta‐xylosidase activity was associated with the cell wall‐enriched fraction of different organs of wild‐type plants. The level of activity correlates with transcript accumulation of AtBXL1 and other AtBXL1‐related genes. Transgenic plants expressing the AtBXL1 cDNA in antisense orientation were generated. Lines exhibiting the highest decrease in AtBXL1 transcript accumulation and beta‐xylosidase activity had phenotypic alterations. This newly identified gene is proposed to be involved in secondary cell wall hemicellulose metabolism and plant development.
Module‐specific regulation of the β‐phaseolin promoter during embryogenesis
Authors: Chandrasekharan Mahesh B. , Bishop Kenneth J. , Hall Timothy C.
Published: March 2003

Thephaspromoter displays stringent spatial regulation, being very highly expressed during embryogenesis and completely silent during all phases of vegetative development in bean,Phaseolus vulgaris. This pattern is maintained in transgenic tobacco and, as shown here,Arabidopsis. Dimethyl sulphatein vivofootprinting analyses revealed that over 20cis‐elements within the proximal 295 bp of thephaspromoter are protected by factor binding in seed tissues whereas none are bound in leaves. The hypothesis that this complex profile represents a summation of several module (cotyledon, hypocotyl, and radicle)‐specific factor–DNA interactions has been explored by the incorporation of site‐directed substitution mutations into 10 locations within the −295phaspromoter. Only 2.6% of−295phaspromoter activity remained after mutation of theG‐box; theCCAAATbox, theE‐box and theRYelements were also found to mediate high levels of expression in embryos. Whereas theCACAelement has dual positive and negative regulatory roles, thevicilinbox was identified as a strong negative regulatory element. The proximal (−70 to −64)RYmotif was found to bestow expression in the hypocotyl while all theRYelements contribute to expression in cotyledons but not to vascular tissue expression during embryogenesis.RYelements at positions −277 to −271, −260 to −254, and −237 to −231 were found to orchestrate radicle‐specific repression. TheG‐box appears to be the functional abscisic acid responsive element and theE‐site may be a coupling element. The results substantiate the concept that autarkicalcis‐element functions generate modular patterning during embryogenesis. They also reflect the existence of both redundancy and hierarchy incis–element interactions. Importantly, the virtually identical expression patterns observed for the two distantly related plants studied argue strongly for the generality of function for the observed factor–element interactions.
Epitope‐specific glutamic acid decarboxylase‐65 autoantibodies in intravenous immunoglobulin preparations
Authors: Hao  , Davis  , Daniels  , Hampe  , Lernmark
Published: March 2003

Intravenous immunoglobulin (IVIG) has been used to treat many autoimmune disorders including Stiff‐Man Syndrome (SMS). SMS is a neurological disorder associated with an immune‐mediated deficiency of gamma‐aminobutyric acid (GABA) due to autoantibodies against the GABA synthesizing enzyme glutamic acid decarboxylase‐65 (GAD65). GAD65 autoantibodies are present among 1–2% of healthy individuals. It can therefore not be excluded that GAD65 autoantibodies may be present in IVIG, which is prepared from multiple blood donors. We report here that GAD65 but not IA‐2 autoantibodies were present in commercial IVIG preparations. The presence of autoantibodies may affect the outcome of IVIG treatment and screening commercial preparations of IVIG for GAD65 autoantibodies is therefore recommended before treating patients.
The impact of a 10‐year audit cycle on blood usage in a district general hospital
Authors: James R. M. , Brown S. , Parapia L. A. , Williams A. T.
Published: March 2003

. As clinical governance moves from concept to practice, it is emerging as a realistic strategy to promote and improve quality within the National Health Service, as well as satisfying the demand for external accountability. In the context of blood transfusion, the area of responsibility encompasses product liability, as well as efficient use of blood as a resource and transfusion as an appropriate clinical response. Clinical governance may be a modern catch phrase, but the principles it enshrines have long been established within blood transfusion, and in other aspects of haematology. Here, an audit cycle comprising four audits over a 10‐year period to monitor the use of cross‐matched blood in a large district general hospital is described.

Initially, blood use was considered by hospital site, and by the surgical procedure for which it was requested. Later, the scope of the audit was expanded to consider usage by individual consultant. A standard of efficient use of cross‐matched blood was taken to be a cross‐match to transfusion ratio of < 1·5.

The information was reviewed by the hospital transfusion committee, who have a key role in co‐ordinating and assessing the practice of transfusion within a hospital. In this hospital, audit has been one of the main tools for improving practice, in particular by enabling the implementation and continuous revision of a maximum blood order schedule.

Further, as the process of audit has developed, problem areas have been highlighted, and strategies to improve usage have been brought in with encouraging results. The audit is now being expanded again to include a greater focus on usage of cross‐matched blood in the nonsurgical setting.
RHDsequencing: a new tool for decision making on transfusion therapy and provision of Rh prophylaxis
Authors: Legler T. J. , Maas J. H. , Köhler M. , Wagner T. , Daniels G. L. , Perco P. , Panzer S.
Published: March 2003

. The serological differentiation of weak D from partial D, D‐negative and D‐positive is not always unequivocal. Therefore, sequencing of theRHDgene is required in some cases. Very recently, several new differences betweenRHDandRHCEhave been identified which permitted us to design primers close to the exon/intron boundaries of theRHD‐exons. We evaluated these primers in 83 D‐positive and 18 D‐negative blood donors and applied the new method for the characterization of theRHDgene in six individuals with weak D phenotype. The amplification reactions were concordant with serological findings in 100 of 101 donors (99·0%). In one D‐positive donor the PCR for exons 2 and 5 gave a negative result, while the sequence of the remaining eight exons was unchanged. By sequencing samples with very weak D serological reactions, we identified weak D type 4.2.2 and weak D type 15, both previously reported to be associated with anti‐D‐alloimmunization. Consequently, we recommended the selection of D‐negative blood in the weak D type 4.2.2 patient, and the provision of Rh prophylaxis for pregnant women with weak D type 15. In summary, a newRHDsequencing method was developed which can be applied if serological reactions are inconclusive.
Electrochemiluminescent detection of bacteria in blood components
Authors: Rider J. , Newton A.
Published: March 2003

SummaryTransfusion‐transmitted bacterial infections cause significant patient morbidity and mortality. This study aimed to improve the sensitivity of a nucleic acid‐based electrochemiluminescence (ECL) assay for pretransfusion bacterial testing of cellular blood components. The approach is dependent on the detection of bacterial 16S ribosomal RNA (rRNA). The modifications studied included the use of a chaotrope‐based lysis buffer with high‐energy mechanical cell disruption by RiboLysis™, increased ruthenium (Ru2+) labelling per 16S rRNA molecule and concomitant use of fluorescent nucleic acid dyes (CyQUANT®, Syto® 17 red and Syto® 61 red). The methodological changes made did lead to more effective bacterial cell disruption and enhanced ECL signal generation. Nevertheless, assay sensitivity was only slightly improved at ∼104−105 colony forming units per mL (CFU mL−1) and the results were highly inconsistent. The method is still not sensitive to the required 102 CFU mL−1and remains impractical for routine use in blood centres.
An unusual case of hyperkalaemia‐induced cardiac arrest in a paediatric patient during transfusion of a ‘fresh’ 6‐day‐old blood unit
Authors: Baz E. M. K. , Kanazi G. E. , Mahfouz R. A. R. , Obeid M. Y.
Published: March 2003

Summary A well‐recognized complication of the transfusion of red blood cells (RBCs) is hyperkalaemia. This occurs in paediatric or adult patients receiving massive transfusion and can lead to cardiac arrest. Hyperkalaemia may follow the transfusion of ‘stored’ RBCs and/or haemolysed units, and depends on the quantity and rate of transfusion. We report on an unusual case of hyperkalaemia‐induced cardiac arrest during transfusion of a ‘fresh’ blood unit. A 62‐day‐old baby girl was scheduled for a construction of a Blalock–Taussig shunt, after the completion of anastomosis, and upon release of vascular control, there was bleeding at the anastomotic site that was controlled with a suture placement. To compensate for the blood loss, a stat order was given for a push of 120 mL of RBCs over 10 min through the inferior vena cava central line. The blood unit was 6 days old and had been gamma‐irradiated 48 h earlier. Shortly after the transfusion, the patient's electrocardiogram showed changes typical of hyperkalaemia; she then went into cardiac asystole. The blood unit potassium concentration was 55·3 mmol L−1, which flushed the atrioventricular node during transfusion.

This is the first report of a high potassium level found in a ‘fresh’, less than 7 days old, nonhaemolysed RBC blood unit. The high concentration of potassium in this unit seems to be due to accelerated alterations of the RBC sodium/potassium adenosine triphosphatase pump (Na+/K+ pump), resulting in the release of intracellular potassium. This early and severe alteration of the pump and the unusually high potassium level may be due to as yet unexplained causes, warranting awareness, future investigation and routine saline washing of ‘fresh’ RBCs for paediatric patients who are candidates for central line transfusion.
Yellow fever vaccination during pregnancy and spontaneous abortion: a case‐control study
Authors: De A. Nishioka Sérgio , Nunes‐Ara£jo F. R. F. , Pires Waldely P. , Silva Flávia A. , Costa Hégena L.
Published: March 2003

objective
 
 To assess a possible association between Yellow fever (YF) vaccine (inadvertently) administered during early pregnancy and spontaneous abortion.method  A hospital‐based case‐control study conducted in a Brazilian town after a YF vaccine campaign that followed an epidemic of dengue. The study included 39 women who attended a university hospital with spontaneous abortion (cases) and 74 pregnant women attending the antenatal clinic of that hospital (controls).results  The crude odds ratio (relative risk estimate) of this association was 2.49, which dropped to 2.29 (95% CI 0.65–8.03) when adjusted for several confounders by multiple logistic regression. Dengue and exposure to organophosphate insecticide fogging during pregnancy were not associated with spontaneous abortion.conclusion  This study, although small and with low power, provides some evidence that women vaccinated with YF vaccine during early pregnancy have an increased risk of having spontaneous abortion. Based on these findings a sensible recommendation should be to avoid YF vaccination of pregnant women unless their risk of acquiring YF outweighs the risk of vaccine‐related abortion.
Respiratory syncytial virus infection in tropical and developing countries
Authors: Weber Martin W. , Weber Martin W. , Mulholland E. Kim , Mulholland E. Kim , Greenwood Brian M.
Published: March 2003

Little is known about the epidemiology of respiratory syncytial virus (RSV) infection in tropical and developing countries; the data currently available have been reviewed. In most studies, RSV was found to be the predominant viral cause of acute lower respiratory tract infections (ALRI) in childhood, being responsible for 27– 96% of hospitalised cases (mean 65%) in which a virus was found. RSV infection is seasonal in most countries; outbreaks occur most frequently in the cold season in areas with temperate and Mediterranean climates and in the wet season in tropical countries with seasonal rainfall. The situation on islands and in areas of the inner tropics with perennial high rainfall is less clear‐cut. The age group mainly affected by RSV in developing countries is children under 6 months of age (mean 39% of hospital patients with RSV). RSV‐ALRI is slightly more common in boys than in girls. Very little information is available about the mortality of children infected with RSV, the frequency of bacterial co‐infection, or the incidence of further wheezing after RSV. Further studies on RSV should address these questions in more detail. RSV is an important pathogen in young children in tropical and developing countries and a frequent cause of hospital admission. Prevention of RSV infection by vaccination would have a significant impact on the incidence of ALRI in children in developing countries.
Schistosoma mansoni, intestinal parasites and perceived morbidity indicators in schoolchildren in a rural endemic area of western Côte d'Ivoire
Authors: Utzinger  , Utzinger  , N'Goran  , N'Goran  , Esse Aya  , Acka Adjoua  , Lohourignon  , Tanner  , Lengeler
Published: March 2003

Summary There is a great need for rapid and low‐cost identification of communities at high risk of intestinal schistosomiasis. We report the development of a questionnaire approach that may do so. In the first phase, 209 schoolchildren from 3 neighbouring villages in a rural area endemic for intestinal schistosomiasis in western Côte d’Ivoire were screened for Schistosoma mansoni and other helminths on 4 consecutive days using Kato‐Katz thick smears. Daily infection prevalences of S. mansoni were high (60%–71%) and the cumulative infection prevalence was 92.3%. Infections with hookworms and Ascaris lumbricoides were also frequent, with cumulative prevalences of 60.8% and 38.3%, respectively. On day 3, the presence of Entamoeba histolytica/E. dispar and Giardia lamblia was assessed by a faecal concentration procedure. In the second phase, focus group discussions (FGD) were conducted: in each village one FGD with heavily infected children and one FGD with lightly or S. mansoni‐uninfected schoolchildren to assess their perception of morbidity. The aim was to establish local terms indicating S. mansoni infections. ‘Diarrhoea’, ‘blood in the stools’, ‘stomach disorders’ and 4 terms in the local Yacouba/Dioula languages were frequently used by infected children. A simple questionnaire was then developed and the headteachers interviewed all schoolchildren individually. ‘Blood in stools’, gnon and toto were reported significantly more frequently among moderately and heavily S. mansoni‐infected children than by those not or only lightly infected. The term gloujeu indicated borderline significance. The best diagnostic performance was found for ‘blood in stool’ (sensitivity: 47%; specificity: 76%; positive predictive value: 66%; negative predictive value: 60%). All schistosomiasis infections were treated with a single oral dose of praziquantel (40 mg/kg body weight) and the same questionnaire was re‐administered 6 weeks post‐treatment. Statistically significantly less children reported having had ‘blood in stool’ and ‘gloujeu’ after treatment (McNemar’s (χ2‐test, P < 0.01). We conclude that ‘blood in stool’, ‘gnon’, ‘toto’ and ‘gloujeu’ are the most reliable reported symptoms for rapid and low‐cost identification of communities that are at high risk of S. mansoni infections in Côte d’Ivoire.
Yellow fever outbreak in Kaffrine, Senegal 1996: epidemiological and entomological findings
Authors: Thonnon  , Spiegel  , Diallo  , Sylla  , Fall  , Mondo  , Fontenille
Published: March 2003

In November 1996 a yellow fever (YF) outbreak occurred near Kaffrine in the central part of Senegal. Thirty‐six deaths were notified, all children under 15 years of age. The YF diagnosis was confirmed by MAC‐ELISA or by virus isolation. The immune status against YF virus of a sample population of 449 individuals was determined, and 31 confirmed cases and 69 asymptomatic cases were reported. Distribution of YF cases and incidence rate decreased with age, while the attack rate was stable in all age groups. Larva indices were high and Aedes aegypti was common in all villages, causing man‐to‐man transmission. The greatest risk of YF disease was lack of immunity, especially in individuals <20 years of age. The outbreak was rapidly controlled by an emergency immunization campaign. YF epidemics occurred in Senegal over two consecutive years. The last outbreak reached the main road to Dakar and the risk of spread to urban areas has increased.
Cultural interpretations of contagion
Authors: Caprara Andrea
Published: March 2003

Anthropological research in recent years has examined how single diseases such as Aids, tuberculosis, measles, malaria and leprosy are conceptualized by laypersons in non‐Western societies. But how is disease transmission itself interpreted in other cultures? Data from ethnographical studies in Côte d'Ivoire and the Afro‐Brazilian culture in Bahia, Brazil show that the interpretations of contagion and preventive practices cut across society involving five main relationships: empirical and analogical thinking, symbolic factors and social organization, the concept of person and body elements, natural and supernatural powers and individual and contextual factors. There is not a general theory, such as Pasteur's theory of germs. Instead,contagion presents itself as a transversal, multidimensional concept crossing and interconnecting society and culture. Public health programmes aimed at controlling infectious diseases need first to understand how contagion is conceptualized by laypersons, the extent to which diseases are considered infectious and the relation between perceptions and preventive practices. This would help in implementing infectious disease control programmes within local contexts based on meaningful community participation.
Latent class analysis permits unbiased estimates of the validity of DAT for the diagnosis of visceral leishmaniasis
Authors: Boelaert Marleen , El Safi Sayda , Goetghebeur Els , Gomes‐Pereira Sandra , Le Ray Dominique , Van der Stuyft Patrick
Published: March 2003

Summary background Substantial uncertainty surrounds the specificity of the Direct Agglutination Test (DAT) for visceral leishmaniasis (VL) in clinical suspects, since no good gold standard exists for unequivocally identifying diseased subjects. We explored the Latent Class Analysis (LCA) modelling technique to circumvent this problem.

patients and methods Data on 149 clinical suspects recruited in 1993–96 during a multicentre study in Sudan were re‐examined. Clinical data, lymph node and bone marrow aspirate and DAT results were available. IFAT was performed in 1997 on stored filter paper blood of 80 individuals. Classical Validity Analysis (CVA) in a 2 × 2 contingency table with parasitology as a gold standard was compared with the parameter estimates produced by the best fitting LCA model.

results The sensitivity estimates of DAT produced by CVA (98% (89%‐100%)) were almost exactly reproduced by LCA. The specificity estimates by LCA were substantially higher than those obtained in CVA. Specificity of DAT depended, however, on whether the subject was treated for VL before. In subjects without prior treatment, CVA estimated DAT specificity at 68% (56%– 79%), whereas LCA estimated it at 85% (63%– 100%).

conclusion LCA modelling proved a useful tool, as it gave consistent estimates of test characteristics and allowed for control of confounding factors and interaction effects. Since VL is a life‐threatening disease for which expensive but effective and safe treatment exists, a clinical suspect in an endemic area should be treated on the basis of a positive DAT result.
Dengue: an evaluation of dengue severity in French Polynesia based on an analysis of 403 laboratory‐confirmed cases
Authors: Murgue Bernadette , Deparis Xavier , Chungue Eliane , Cassar Olivier , Roche Claudine
Published: March 2003

Summary We conducted a retrospective study of 403 laboratory‐confirmed dengue cases hospitalized in Tahiti between August 1989 and March 1997. According to standard WHO criteria, 337 of these cases were dengue fever (DF) and 64 were dengue haemorrhagic fever (DHF). Of the 10 fatal cases, 6 were DF and 4 were DHF. As an alternative, we used a correspondence analysis procedure to define dengue severity based on basic clinical and biological criteria for which we assigned a severity score, and then selected the 50 most severe cases from this analysis. Of the latter, 17 patients had been classified as DF and 33 as DHF by the WHO criteria. From this analysis, haemorrhages and decreased platelets counts associated with hepatic disorders are the main criteria associated with the severe dengue cases. Thus in our study population, the WHO classification does not account for the overall severity of dengue; hepatic failure should be considered as a specific severe form of dengue since plasma leakage, which is the pathophysiological hallmark of DHF, is only one of the pathogenic mechanisms leading to severity.
A randomized, double‐blind, placebo‐controlled clinical trial of vitamin A in Mozambican children hospitalized with nonmeasles acute lower respiratory tract infections
Authors: Julien Manuel Romano , da Cruz Gomes Aurélio , Varandas Luis , Rodrigues Paula , Malveiro Filomena , Aguiar Pedro , Kolsteren Patrick , Van der Stuyft Patrick , Hildebrand Katherine , Labadarios Demetre , Ferrinho Paulo
Published: March 2003

Summary objective The objective of this study was to test the potential of routine vitamin A supplementation at admission to speed up recovery during hospitalization for acute lower respiratory tract infections (ALRI) and to decrease the levels of morbidity at 6 weeks after discharge. The study was conducted in the Central Hospital of Maputo (CHM), Mozambique, from 1995 to 1997.

methods Children aged 6–72 months with ALRI admitted to the paediatric wards of the CHM were assigned to a supplementation group (n = 71, receiving 200000 IU of vitamin A) or a control group (n = 93, receiving a placebo).

results The prevalence of vitamin A deficiency was very high and similar between the two groups. The median number of inpatient days for the supplementation group was 3, for the placebo group 4 days. On day 5 the rate of clinical discharge was 88.4% (n = 61/69) in the experimental intervention group and 73.9% (n = 65/88) in the placebo group (P = 0.023).

conclusion We found a statistically significant reduction in duration of admission among vitamin A‐supplemented children with ALRI. This effect is in line with what is known about the role of vitamin A in human defence and immune mechanisms and with the serological evidence of the extent of vitamin A deficiency among the children in this trial.
Malaria prevalence and a brief entomological survey in a village surrounded by rice fields in Khammouan province, Lao PDR
Authors: Kobayashi Jun , Somboon Pradya , Keomanila Hongkham , Inthavongsa Somchith , Nambanya Simone , Inthakone Souliya , Sato Yoshiya , Miyagi Ichiro
Published: March 2003

Summary We surveyed Nongceng, a village in a south‐eastern province of Lao PDR, for malaria and its vectors. Nongceng is situated in a basin and surrounded by rice fields. In February 1998 (dry season), 28.6% of 126 villagers were infected with malaria, and in September 1998 (rainy season), 16.3% of 147 villagers. The prevalence of malaria infection was consistently high in children under 10, and the predominant malaria species was Plasmodium falciparum. In brief surveys of the mosquitoes performed on the same day as the malaria surveys, 2007 Anopheles females from 12 species were collected by means of human bait, animal bait and resting collections. Of the vector species known to be important in transmitting malaria in neighbouring Thailand –An. minimus, An. dirus, and An. maculatus groups – only An. minimus was found. Its density was, however, very low in both seasons and it was therefore unlikely to be the vector. In fact, An. nivipes accounted for more than 65% of all mosquitoes collected and was the most common species collected from human baits. The results of this study show that endemic areas of malaria in Lao PDR are not necessarily related to forest. Rather, An. nivipes is suspected to be the most important vector.
A randomized comparison of branded sodium stibogluconate and generic sodium stibogluconate for the treatment of visceral leishmaniasis under field conditions in Sudan
Authors: Veeken Hans , Ritmeijer Koert , Seaman Jill , Davidson Robert
Published: March 2003

Summary objective  To compare the outcome of treatment of Sudanese kala‐azar patients treated under field conditions with either branded sodium stibogluconate (SSG) (Pentostam GlaxoWellcome) or generic SSG (Albert David Ltd, Calcutta, supplied by International Dispensary Association, Amsterdam).

method  Randomised comparison. 271 patients were treated with Pentostam and 245 with generic SSG.

results  No statistically significant differences in cure rate or mortality were detected between Pentostam and generic SSG. No differences in side‐effects between the two drugs were noted. The initial cure rate at the time of discharge was 93.7 and 97.6%, respectively; the death rate during treatment 5.9 and 2.4%. Six months follow up was achieved in 88.5% of the discharged patients. Two patients had died in the Pentostam group and two had died in the generic SSG group, giving a final death rate of 7.5 and 3.7%. The number of relapses in the Pentostam and generic SSG groups were 3 and 1, respectively. The final cure rates, calculated at 6 months after discharge, were 91.3% and 95.9%.

conclusion  No difference was observed in the performance of generic SSG compared to Pentostam for the treatment of visceral leishmaniasis in Sudan. Generic SSG can be routinely and safely used for the treatment of kala‐azar. Generic SSG costs only 1/14 of the price of Pentostam. The use of generic SSG may make treatment of kala‐azar affordable for national governments in Africa.
The impact of educational videotapes on water contact behaviour of primary school students in the Dongting Lakes region, China
Authors: Yuan Liping , Manderson Lenore , Tempongko Ma Sandra B. , Wei Wangyuan , Aiguo Pen
Published: March 2003

Multimedia has become increasingly important in educational programmes in schools in all societies, and has potential value for health education. We developed a video and a comic book on the transmission and prevention of schistosomiasis for use in primary schools in endemic areas of China. The material was designed to increase children’s knowledge of schistosomiasis as an environmental disease and to encourage them to reduce their contact with unsafe water sources. To test the effectiveness of the video and booklet, a quasi‐experimental study was conducted among 1739 children in 50 primary schools in the Dongting Lake region. A self‐administered questionnaire pre‐ and post‐intervention showed a significant increase in knowledge about schistosomiasis in the intervention schools. Significantly, this change was associated with a decrease in contact with unsafe water sources, as established from water contact observations. This behavioural change suggests the value of short, targeted educational interventions to decrease risk of infection.
Prevalence of point mutations in the dihydrofolate reductase and dihydropteroate synthetase genes of Plasmodium falciparum isolates from India and Thailand: a molecular epidemiologic study
Authors: Biswas S. , Escalante A. , Chaiyaroj S. , Angkasekwinai P. , Lal A. A.
Published: March 2003

Pyrimethamine‐sulfadoxine (PS) is used as a second‐line treatment for P. falciparum malaria patients who fail to respond to chloroquine. Resistance to these drugs has been shown to encode with point mutations in dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS) genes. Our aim was to assess the comparative rate of point mutation occurring in DHFR and DHPS genes among P. falciparum isolates from India and Thailand where the use of PS is at a different rate. We used the mutation‐specific polymerase chain reaction (PCR) technique and mutation‐specific restriction digestion to determine the prevalence of DHFR and DHPS gene mutations at codons 16, 51, 59, 108, 164 and at 436, 437, 581 and 613, respectively. In the 89 clinical isolates from India, in the case of the DHFR gene, we found 71 of S108N, 10 of N51I, 28 of C59R and four of I164L types. Among the 50 isolates from Thailand the rate of point mutations in the DHFR gene was higher at four codon positions. We found 47 of S108N, 18 of N51I, 23 of C59R and 12 of I164L types. None of the isolates from either country possessed the paired mutations S108T and A16V. Mutations of the DHPS gene were less frequent among the Indian isolates: 4.5% showed DHPS gene mutation, two of S436F, A437G, A613T and two of S436F, A613T; whereas 66% (33/50) of the Thai isolates had mutated at codons 436, 437, 581 and 613 which include 13 of S436F, 15 of A437G, 19 of A581G and 25 of A613S/T, ranging from single to quadruple mutant types. Among the Indian isolates, DHFR point mutations were very frequent and 85/89 had a wild type DHPS genetic profile. The pattern of mutations in the samples from Thailand was different, as most were associated with point mutations in DHFR and DHPS genes.
Latex based, rapid and easy assay for human leptospirosis in a single test format
Authors: Smits Henk L. , Chee Howard D. , Eapen C. K. , Kuriakose Mariamma , Sugathan Sheela , Gasem M. Hussein , Yersin Claude , Sakasi David , Lai‐a‐Fat Rudy F. M. , Hartskeerl Rudy A. , Liesdek Bernadette , Abdoel Theresia H. , Goris Marga G. A. , Gussenhoven George C.
Published: March 2003

Leptospirosis is an often severe disease which requires prompt treatment. Laboratory testing is required to reach a valid diagnosis. An agglutination assay for the detection of Leptospira‐specific antibodies consisting of individually wrapped agglutination cards containing a stable, dried detection reagent is evaluated. The assay is simply performed by suspending the dried reagent with a drop of serum. The result is obtained within 30 s. The sensitivity of the assay varied with the stage of the disease and was 72.3% for samples collected during the first 10 days of the illness and 88.2% for samples collected at a later stage. The specificity was 93.9% and 89.8%, respectively. These characteristics make the test ideal for use in areas where the disease is common and where laboratory support is not routinely available.