bluuebunny/crossref_metadata_2025 huggingface dataset:
E2F sites that can interact with E2F proteins cloned from rice are required for meristematic tissue‐specific expression of rice and tobacco proliferating cell nuclear antigen promoters
Authors: Kosugi Shunichi , Ohashi Yuko
Published: March 2003

Plants have recently been found to have E2F‐like and Rb‐like proteins, regulators responsible for the G1(G0)‐S phase transition of the cell cycle in animals. Here we show that E2F is involved in transcription of plant genes for proliferating cell nuclear antigen (PCNA), which is required for DNA replication. Potential E2F binding sites found in the rice PCNA promoters mediated transcriptional activation in actively dividing cells and tissues of tobacco, but not transcriptional repression in terminally differentiated tissues, as also observed for the PCF binding sites previously found in the rice promoter. Similar results were obtained from analyses for a PCNA promoter isolated from tobacco, which contained two E2F‐like sites, each with a different degree of contribution to the promoter activation. These E2F‐like sites except for a rice site were indeed bound specifically by recombinant proteins of rice E2F, OsE2F1 and OsE2F2, and complexes of OsE2F1 with Arabidopsis DP proteins. Furthermore, OsE2F1 had the ability to transactivate an E2F‐reporter gene containing the tobacco E2F site on co‐expression with an Arabidopsis DP, and the transactivation was greatly enhanced by tagging a canonical nuclear localization signal to OsE2F1, suggesting a nuclear import‐mediated regulation of the OsE2F1 function. In addition, we found that a large number of replication‐ and mismatch repair‐associated genes in Arabidopsis contain E2F binding sequences conserved in their predicted promoter regions.
The ArabidopsisREF8 gene encodes the 3‐hydroxylase of phenylpropanoid metabolism
Authors: Franke Rochus , Humphreys John M. , Hemm Matthew R. , Denault Jeff W. , Ruegger Max O. , Cusumano Joanne C. , Chapple Clint
Published: March 2003

The activity of p‐coumarate 3‐hydroxylase (C3H) is thought to be essential for the biosynthesis of lignin and many other phenylpropanoid pathway products in plants; however, no conditions suitable for the unambiguous assay of the enzyme are known. As a result, all attempts to purify the protein and clone its corresponding gene have failed. By screening for plants that accumulate reduced levels of soluble fluorescent phenylpropanoid secondary metabolites, we have identified a number of Arabidopsis mutants that display a reduced epidermal fluorescence (ref) phenotype. Using radiotracer‐feeding experiments, we have determined that the ref8 mutant is unable to synthesize caffeic acid, suggesting that the mutant is defective in a gene required for the activity or expression of C3H. We have isolated the REF8 gene using positional cloning methods, and have verified that it encodes C3H by expression of the wild‐type gene in yeast. Although many previous reports in the literature have suggested that C3H is a phenolase, the isolation of the REF8 gene demonstrates that the enzyme is actually a cytochrome P450‐dependent monooxygenase. Although the enzyme accepts p‐coumarate as a substrate, it also exhibits significant activity towards other p‐hydroxylated substrates. These data may explain the previous difficulties in identifying C3H activity in plant extracts and they indicate that the currently accepted version of the lignin biosynthetic pathway is likely to be incorrect.
Fucosylated arabinogalactan‐proteins are required for full root cell elongation in arabidopsis
Authors: Van Hengel Arjon J. , Roberts Keith
Published: March 2003

The Arabidopsis thaliana mutant mur1 is affected in the biosynthesis of l‐fucose and has less than 2% of the normal amounts of this sugar in the cell walls of its aerial parts. Although in roots the reduction of l‐fucose is only 40%, this causes a decrease of about 50% in root cell elongation. Since arabinogalactan‐proteins (AGPs) are known to play a role in plant cell expansion we studied the composition of mur1 root AGPs. Arabidopsis root AGPs were shown to contain l‐fucose, which was reduced in level in mur1 AGPs. In wild‐type plants, an l‐fucose containing epitope is present in AGPs in the cell wall of differentiating root cells. Addition of eel lectin, which specifically recognizes this epitope, and not fucose in other wall polymers, can phenocopy mur1 roots. Several lines of evidence are presented to support the contention that l‐fucose containing root AGPs are required for the full elongation of root cells.
Phototropin LOV domains exhibit distinct roles in regulating photoreceptor function
Authors: Christie John M. , Swartz Trevor E. , Bogomolni Roberto A. , Briggs Winslow R.
Published: March 2003

Phototropins (phot1 and phot2) are autophosphorylating serine/threonine kinases that function as photoreceptors for phototropism, light‐induced chloroplast movement, and stomatal opening in Arabidopsis. The N‐terminal region of phot1 and phot2 contains two specialized PAS domains, designated LOV1 and LOV2, which function as binding sites for the chromophore flavin mononucleotide (FMN). Both LOV1 and LOV2 undergo a self‐contained photocycle, which involves the formation of a covalent adduct between the FMN chromophore and a conserved active‐site cysteine residue (Cys39). Replacement of Cys39 with alanine abolishes the light‐induced photochemical reaction of LOV1 and LOV2. Here we have used the Cys39Ala mutation to investigate the role of LOV1 and LOV2 in regulating phototropin function. Photochemical analysis of a bacterially expressed LOV1 + LOV2 fusion protein indicates that LOV2 functions as the predominant light‐sensing domain for phot1. LOV2 also plays a major role in mediating light‐dependent autophosphorylation of full‐length phot1 expressed in insect cells and transgenic Arabidopsis. Moreover, photochemically active LOV2 alone in full‐length phot1 is sufficient to elicit hypocotyl phototropism in transgenic Arabidopsis, whereas photochemically active LOV1 alone is not. Further photochemical and biochemical analyses also indicate that the LOV1 and LOV2 domains of phot2 exhibit distinct roles. The significance for the different roles of the phototropin LOV domains is discussed.
On‐line measurements of K+ activity in the tensile water of the xylem conduit of higher plants
Authors: Wegner Lars H. , Zimmermann Ulrich
Published: March 2003

In higher plants the xylem is the main pathway for anti‐gravitational, long‐distance transport of nutrients and water from the root through the shoot to the upper leaves. In the xylem conduit water is in a metastable state if tension larger than 0.1 MPa (i.e. negative pressure) is developed. While diurnal changes in negative pressure of individual xylem vessels can quite accurately be recorded by the minimal‐invasive xylem pressure probe technique and water flow by non‐invasive NMR techniques, the problem of continuous monitoring of solute flow remains a hitherto unresolved challenge. As shown here, integration of a K+ selective and a potential measuring microelectrode into the xylem pressure probe allowed on‐line measurements of the K+ activity in individual xylem vessels of maize roots together with pressure and trans‐root potential, the potential difference between the xylem and the external medium (i.e. the overall driving force of ions through the root tissue). When light irradiation was increased from 10 µmol m−2 s−1 to 300 µmol m−2 s−1 and negative pressure developed in the vessel, xylem K+ activity dropped from 3.6 ± 2.6 mm to 0.9 ± 0.7 mm (n = 16), whereas the trans‐root potential depolarized from −2 ± 11 mV to + 12 ± 11 mV (n = 11), i.e. by + 14 ± 7 mV. The effect of light on all three parameters was reversible. Exposure of the root to various K+ activities in the bath ranging from 0.1 to 43 mm revealed that the K+ activity of the xylem sap was shielded against short‐term fluctuations in K+ supply to a large extent. In contrast, control experiments in which the root was cut 1 cm below the probe insertion point, allowing direct entry of external K+ into the xylem vessels, demonstrated that the xylem equilibrated rapidly with external K+. This was taken simultaneously as a proof for the correct reading of the probe.
Sulfate reduction is increased in transgenic Arabidopsis thaliana expressing 5′‐adenylylsulfate reductase from Pseudomonas aeruginosa
Authors: Tsakraklides George , Martin Melinda , Chalam Radhika , Tarczynski Mitchell C. , Schmidt Ahlert , Leustek Thomas
Published: March 2003

The two‐electron reduction of sulfate to sulfite in plants is mediated by 5′‐adenylylsulfate (APS) reductase, an enzyme theorized to be a control point for cysteine synthesis. The hypothesis was tested by expression in Arabidopsis thaliana under transcriptional control of the CaMV 35S promoter of the APS reductase from Pseudomonas aeruginosa (PaAPR) fused with the rbcS transit peptide for localization of the protein to plastids. PaAPR was chosen for the experiment because it is a highly stable enzyme compared with the endogenous APS reductase of A. thaliana, and because PaAPR is catalytically active in combination with the plant thioredoxins m and f indicating that it would likely be catalytically active in plastids. The results indicate that sulfate reduction and O‐acetylserine (OAS) production together limit cysteine synthesis. Transgenic A. thaliana lines expressing PaAPR accumulated sulfite, thiosulfate, cysteine, γ‐glutamylcysteine, and glutathione. Sulfite and thiosulfate increased more than did cysteine, γ‐glutamylcysteine and glutathione. Thiosulfate accumulation was most pronounced in flowers. Feeding of OAS to the PaAPR‐expressing plants caused cysteine and glutathione to increase more rapidly than in comparably treated wild type. Both wild‐type and transgenic plants accumulated sulfite and thiosulfate in response to OAS feeding. The PaAPR‐expressing plants were slightly chlorotic and stunted compared with wild type. An attempt to uncover the source of thiosulfate, which is not thought to be an intermediate of sulfate reduction, revealed that purified β‐mercaptopyruvate sulfurtransferase is able to form thiosulfate from sulfite and β‐mercaptopyruvate, suggesting that this class of enzymes could form thiosulfate in vivo in the presence of excess sulfite.
Developmental events and shoot apical meristem gene expression patterns during shoot development in Arabidopsis thaliana
Authors: Cary Andrew J. , Che Ping , Howell Stephen H.
Published: March 2003

Critical developmental and gene expression profiles were charted during the formation of shoots from root explants in Arabidopsis tissue culture. Shoot organogenesis is a two‐step process involving pre‐incubation on an auxin‐rich callus induction medium (CIM) during which time root explants acquire competence to form shoots during subsequent incubation on a cytokinin‐rich shoot induction medium (SIM). At a histological level, the organization of shoot apical meristems (SAMs) appears to occur during incubation on SIM about the time of shoot commitment, i.e. the transition from hormone‐dependent to hormone‐independent shoot development. Genes involved in SAM formation, such as SHOOTMERISTEMLESS (STM) and CLAVATA1 (CLV1), were upregulated at about the time of shoot commitment, while WUSCHEL (WUS) was upregulated somewhat earlier. Genes required for STM expression, such as CUP‐SHAPED COTYLEDON 1 and 2 (CUC1 and 2) were upregulated prior to shoot commitment. Gene expression patterns were determined for two GFP enhancer trap lines with tissue‐specific expression in the SAM, including one line reporting on CUC1 expression. CUC1 was generally expressed in callus tissue during early incubation on SIM, but later CUC1 was expressed more locally in presumptive sites of shoot formation. In contrast, the expression pattern of the enhancer trap lines during zygotic embryogenesis was more localized to the presumptive SAM even in early stages of embryogenesis.
Interaction of NtCDPK1 calcium‐dependent protein kinase with NtRpn3 regulatory subunit of the 26S proteasome in Nicotiana tabacum
Authors: Lee Sang Sook , Cho Hye Sun , Yoon Gyeong Mee , Ahn Joon‐Woo , Kim Hyong‐Ha , Pai Hyun‐Sook
Published: March 2003

Using a yeast two‐hybrid system, we identified NtRpn3, a regulatory subunit of 26S proteasome, as an interacting protein of NtCDPK1 calcium‐dependent protein kinase in Nicotiana tabacum. Rpn3 in yeast is an essential protein involved in proteolysis of cell cycle regulatory proteins, and the carrot homolog of Rpn3 was previously isolated as a nuclear antigen that is mainly expressed in the meristem. NtCDPK1 physically interacts with NtRpn3 in vitro in a Ca2+‐independent manner and phosphorylates NtRpn3 in a Ca2+‐dependent manner with Mg2+ as a cofactor. NtCDPK1 and NtRpn3 are co‐localized in the nucleus, nuclear periphery, and around plasma membrane in vivo. Both NtCDPK1 and AtRpn3, an NtRpn3 homolog of Arabidopsis, are mainly expressed in the rapidly proliferating tissues including shoot and root meristems, and developing floral buds. Virus‐induced gene silencing of either NtRpn3 or NtCDPK1 resulted in the phenotypes of abnormal cell morphology and premature cell death in newly emerged leaves. Finally, NtCDPK1 interacts with NtRpn3 in vivo as shown by co‐immunoprecipitation. Based on these results, we propose that NtCDPK1 and NtRpn3 are interacting in a common signal transduction pathway possibly for regulation of cell division, differentiation, and cell death in tobacco.
A prospective study of the risk of transfusion‐acquired viral infections
Authors: Murphy  , Busch  , Tong  , Cornett  , Vyas
Published: March 2003

The risk of transfusion‐transmitted viral infections may be estimated by several methods, but only prospective studies of transfusion recipients can directly measure the incidence, with associated 95% upper confidence bound, of these infections. From 1989 through 1995, 764 recipients of allogeneic or autologous red blood cell transfusions were enrolled; 486 (64%) provided both pretransfusion and 6‐month follow‐up specimens. Both specimens were tested for anti‐HBc, anti‐HCV, anti‐HTLV‐I and anti‐HIV, with appropriate confirmatory testing. Thirty‐nine (8.0%) subjects had seroprevalent anti‐HBc, 19 (3.9%) subjects had seroprevalent anti‐HCV, three (0.6%) subjects had seroprevalent anti‐HTLV‐I/II, and one (0.2%) subject had seroprevalent anti‐HIV. There were no seroconversions for any agent among the 34 patients who received only autologous blood, and no confirmed seroconversions for anti‐HTLV‐I or anti‐HIV among all subjects. There were three seroconversions for anti‐HBc (incidence 1.04 × 10−3; 95% confidence interval (CI) 2.15 × 10−4, 3.05 × 10−3 per allogeneic unit transfused), and two confirmed seroconversions for HCV (incidence 6.94 × 10−4; 95% CI 8.34 × 10−5, 2.51 × 10−3 per allogeneic unit transfused). One of the two anti‐HCV seroconversions occurred in March 1994, after the institution of HCV EIA 2.0 screening of donated blood. Transfusion‐associated seroconversions to hepatitis B and C markers were observed at low rates in the early 1990s despite testing donors for markers of both viruses, whereas seroconversions to HTLV‐I or HIV were less than 1.04 × 103 per allogeneic unit transfused, based upon the upper 95% confidence interval of the zero incidence in this study.
Changes in red‐cell transfusion practice in a tertiary care hospital during the 1990s — a 7‐year study
Authors: Pinkerton  , Tasev  , Coovadia
Published: March 2003

Use of red cells for transfusion in a tertiary care hospital has been studied over a 7‐year period from 1990–1991 to 1996–1997. In this time, red‐cell use has declined by 18% while new patients or admissions to programmes in oncology, trauma or cardiac bypass surgery have increased by 57%, 66% and 73%, respectively. This reduction in red‐cell transfusion has been achieved by a combination of less patients (proportionately) receiving red cells and less red cells being transfused to individual recipients. When the trends are analysed for red‐cell use in four elective surgical procedures there is a significant reduction in both the proportion of patients transfused and the mean number of units used per patient undergoing the procedure. Autologous presurgical blood deposit met about 45% of the blood requirement for those four procedures. A similar decreasing trend in units per patient and proportion of patients transfused red cells was seen for ‘first‐time’ coronary artery bypass surgery. The question arises as to how far this trend may go before adverse effects of undertransfusion become apparent.
Transfusion‐related acute lung injury (TRALI) following autologous stem cell transplant for relapsed acute myeloid leukaemia: a case report and review of the literature
Authors: Leach  , Vora  , Jones  , Lucas
Published: March 2003

A fatal case of transfusion‐related acute lung injury (TRALI) in a child post‐autologous stem cell transplant for relapsed acute myeloid leukaemia is described. The implicated product was a single unit platelet concentrate containing anti‐HLA A2 and granulocyte‐specific anti‐NA1 antibodies. The recipient typed as HLA A2/A2, NA1/NA1. This is the first reported case of TRALI following a transplant procedure for a haematological condition. It is also unusual in that the patient failed to make a full recovery and that two relevant leucocyte antibodies of clear specificity were identified in the donor plasma. The literature relating to the pathophysiology, clinical sequelae and management of TRALI is reviewed.
A method for drying red blood cells for solid‐phase immunoassay
Authors: Tamai  , Mazda
Published: March 2003

To develop a simpler and quicker alloantibody screening method, red cell stroma were bound and dried to microplate wells for use in magnetic‐mixed passive haemagglutination (M‐MPHA) tests. In the procedure of drying stroma, the Triton X‐100‐based haemolysing method gave lowest denaturation of red blood cells, and this method gave increased reactivity to Kidd and Rh antigens and clinically significant antibodies were detected as well as with the M‐MPHA test. But long incubation with Triton X‐100 and using high concentrations of Triton X‐100 gave rise to some reduction in antigenicity, so the precise conditions for haemolysis are critical. This dried stroma‐coated microplate can be stored for longer and more easily at room temperature than nondried intact red blood cells. The new system gave good sensitivity and the overall test time was shortened and should give a particular advantage for mass screening and for automation of this test.
Intravenous immunoglobulin: regulatory perspectives on use and supply
Authors: Farrugia A. , Poulis P.
Published: March 2003

Technological advancements in the fractionation of plasma in the early 1970s led to the production of immunoglobulin preparations which could be administered intravenously. The ability to deliver larger doses than was possible with intramuscular products was accompanied by clinical studies demonstrating the efficacy of immunoglobulin treatment in a number of autoimmune and inflammatory conditions. This has led to a continuing increase in the usage of this product such that, currently, it is considered to be the driving force for plasma procurement. In recent years, difficulties have been experienced in the supply of this product in various markets.

While intravenous immunoglobulins (IVIG) have undoubted clinical superiority over intramuscular products for the majority of indications, their use should be tempered with caution. Early clinical studies revealed that the risk of viral transmission from these products was higher than that of the traditional intramuscular presentation. This has had a profound impact on blood transfusion science as it has provided a major impetus for nucleic acid testing (NAT) for viral agents in blood donations. Perhaps less widely appreciated are the pressures which may be felt in blood services as the traditional drivers for plasma procurement – factor VIII and albumin – become secondary to IVIG. This review discusses the factors affecting the supply and safety of IVIG and the implications of recent global regulatory decisions on the delivery of this product and other therapeutic products derived from human plasma.
A modified Kleihauer technique for the quantification of foetomaternal haemorrhage
Authors: Howarth D. J. , Robinson F. M. , Williams M. , Norfolk D. R.
Published: March 2003

Summary The Kleihauer technique, based on acid elution of maternal red cells, is the mostly widely used technique in the UK to screen for, and estimate the volume of, foetomaternal haemorrhage (FMH) and for determining the need for additional doses of anti‐D immunoglobulin to prevent maternal alloimmunization. However, technicians often report difficulties in identifying and accurately counting maternal red cells in the blood film, leading to imprecision in the calculated FMH. In this report, we describe a simple modification of the standard Kleihauer technique, based on performing acid elution of only half of the film. Compared to the standard method, the modified technique showed improved accuracy and reduced interobserver varability across a range of simulated FMH volumes. There was a high degree of correlation between the new technique and FMH estimated by flow cytometry (r2 = 0·916, P < 0·001). Technicians found the new technique easy to incorporate into routine practice in a busy teaching hospital laboratory and were impressed by the relative ease of counting maternal ghost cells. The modified technique has been used routinely in our laboratory for 3 years, during which time our performance in the UK National External Quality Assurance Scheme for FMH has been uniformly satisfactory.
Alloimmune neonatal neutropenia linked to anti‐HNA‐4a
Authors: Fung Y. L. , Pitcher L. A. , Willett J. E. , Reed C. , Mison L. , Bux J. , Eiber G. , Minchinton R. M.
Published: March 2003

Summary. This is a novel case report of alloimmune neonatal neutropenia (ANN) linked to the neutrophil antibody anti‐HNA‐4a (MART). Since its discovery, the HNA‐4a antigen has never been associated with any clinical neutropenia. A first‐born neonate with respiratory distress was found to be severely neutropenic, because of ANN. The broad reactivity of the antibody together with its capture by CD11b and CD18 in monoclonal antibody immobilization of granulocyte antigen test suggested HNA‐4a specificity. DNA sequencing confirmed that the father is HNA‐4a‐positive and that the mother is HNA‐4a‐negative, supporting the diagnosis of ANN linked to MART.
A systematic approach to the development of a rational malaria treatment policy in Zambia
Authors: Barat Lawrence M. , Himonga Benson , Nkunika Simon , Ettling Mary , Ruebush Trenton K. , Kapelwa Wamibinji , Bloland Peter B.
Published: March 2003

Despite the spread of chloroquine‐resistant Plasmodium falciparum throughout sub‐Saharan Africa, chloroquine (CQ) remains the first‐line treatment for uncomplicated infection in most countries. To assess the efficacy of CQ and sulphadoxine‐pyrimethamine (SP) in Zambia, studies using a standardized 14‐day in vivo test were conducted at 6 geographically representative sites. Febrile children ≤ 5 years of age were treated with standard doses of CQ or SP and monitored for parasitological failure (using modified WHO criteria) and clinical failure (fever with parasitaemia after completion of therapy). RII/RIII (high to moderate level) parasitological failures were identified in 34% to 70% of CQ‐treated children (total N= 300) at the 6 sites and clinical failures in 31% to 48%. SP testing at 2 sites identified RII/RIII failures in 3% and 17% of children and only 1 clinical failure at each site. Because of the high levels of CQ resistance identified in these trials, the Ministry of Health of Zambia convened a national consensus meeting which recommended that Zambia's national malaria treatment policy be modified to make SP available at all health facilities for use in persons who fail initial therapy with CQ. In addition, selected sites, staff, and the methodology from these studies were used to implement a sentinel surveillance system for antimalarial drug efficacy. This systematic approach to antimalarial drug efficacy testing could be easily replicated in other countries seeking to reassess their malaria treatment policies.
Monitoring unmet obstetric need at district level in Morocco
Authors: Belghiti A. , De Brouwere V. , Kegels G. , Van Lerberghe W.
Published: March 2003

Unmet obstetric need was assessed in Taounate province (Morocco) during the year 1995 by monitoring rates of major obstetric intervention for absolute maternal indications. We report results in terms of spatial distribution of the failures of the health care system to provide women with essential emergency obstetric care. An estimated 135 women with life‐threatening conditions did not benefit from the obstetric interventions they required. The paper documents the effects of the monitoring process on the way the provincial team changed their way of dealing with deliveries. Assessment of unmet obstetric need in Taounate province proved feasible and affordable without external budgetary inputs. It provided the team with information on the magnitude of a previously ignored problem. The results were so dramatic as to lead the team to look for causes and solutions. These were clearly not merely technical but systemic in nature.
Measurement of ovalocyte frequency in peripheral blood smears in defining ovalocytosis in Papua New Guinea
Authors: Sapak Peter , Sleigh Adrian , Williams Gail , Peter Wilfred , Ginny Meza , Waranduo Markus
Published: March 2003

Red cell oval morphology is still the only accepted basis for the clinical or epidemiological diagnosis of ovalocytosis. Therefore it is important to know the errors when detecting and counting morphological ovalocytes. In all previous studies of ovalocytosis there was no assessment of the variation which may have occurred in classification due to smearing and staining techniques or the criteria for the diagnosis of ovalocyte morphology; nor was inter or intraobserver variation assessed. We report how different peripheral blood smear methods influence the diagnosis of ovalocytosis in populations in the Madang and East Sepik Provinces in Papua New Guinea. We also examined within and between observer variation in the quantitative assessment of ovalocytosis at ×40 and ×100 microscopy powers. A modified method of making a thin malaria blood smear gave the best preservation of red cell morphology and was adopted for the quantitative ovalocytosis studies. A special haematology smear is unnecessary. Ovalocyte frequency estimations were similar when ×40 and ×100 lenses were used, but ×40 was preferable for assessing morphology. Two observers were consistent in their findings and produced very similar results for the high‐quality smears from the planned Madang survey, and rather different results for the smears from the unplanned routine Sepik survey. We conclude that measurement error for ovalocytosis assessment can be quite small and unimportant, minimized by careful planning and quality control. Otherwise measurement error is substantial and threatens validity of classification and grading of ovalocytosis.
Glutathione‐S‐transferase activity in malarial parasites
Authors: Srivastava P. , Puri S. K. , Kamboj K. K. , Pandey V. C.
Published: March 2003

Summary Glutathione‐S‐transferase (GST) activity has been detected in rodent (Plasmodium berghei, P. yoelii), simian (P. knowlesi) and human (P. falciparum) malarial parasites, and in different intraerythrocytic stages of P. knowlesi (schizont > ring > trophozoite). In chloroquine‐resistant strains of rodent and human malarial parasites GST activity significantly increases compared to sensitive strains. Further, the increase in enzyme activity is directly related to drug pressure of resistant P. berghei. Complete inhibition of chloroquine‐sensitive and resistant P. berghei glutathione‐S‐transferase activities was observed at 2.5 and 5.0 μm concentration of hemin, respectively. An inverse relationship was found between the heme level and enzyme activity of chloroquine‐resistant and sensitive P. berghei. Chloroquine, artemisinin, and primaquine noticeably inhibited GST activity in P. knowlesi.
Risk factors for death in hospitalized dysentery patients in Rwanda
Authors: Legros Dominique , Paquet Christophe , Dorlencourt Fabienne , Le Saoult Elizabeth
Published: March 2003

Summary To evaluate the management of severe dysentery cases in in‐patient facilities during an epidemic of Shigella dysenteriae type 1 (Sd1), and to identify the factors associated with the risk of death, we conducted a prospective cohort study in 10 Rwandese hospitals between September and December 1994. Data were obtained from 849 cases admitted to hospitals with diarrhoea and visible blood in stools. The proportion of patients with persistent bloody diarrhoea was 51.0% at treatment day 3 and 27.9% at treatment day 5. At discharge, 79.9% had improved or were cured. The case fatality ratio was 13.2%, higher for patients treated with nalidixic acid than for those treated with ciprofloxacin (12.2%vs. 2.2%, RR = 5.80, 95% CI = 0.83–40.72). In a logistic regression model three risk factors were significantly associated with an increased risk of death during hospitalization: severe dehydration on admission (adjusted OR = 2.79, 95% CI = 1.46–5.33), age over 50 (adjusted OR vs. 5–49 age group = 3.22, 95% CI = 1.70–6.11) and prescription of nalidixic acid (adjusted OR vs. ciprofloxacin = 8.66, 95% CI = 1.08–69.67). Those results were consistent with reported high levels of resistance of Sd1 to the commonest antibiotics, including nalidixic acid. Patients belonging to groups with a higher risk of dying should be given special medical attention and supportive care. In areas of high resistance to nalidixic acid, severe cases of dysentery should be treated with fluoroquinolones in order to reduce the mortality associated with these epidemics.
Determinants of mortality among children in the urban slums of Dhaka city, Bangladesh
Authors: Hussain Akhtar , Ali S. M. Keramat , Kvåle Gunnar
Published: March 2003

Summary The growing slum population in the developing world is an increasing challenge for local health authorities. Little is known of the patterns of disease occurrence including treatment types offered in this population. The paper describes reported child mortality and its determinants, including the main diseases affecting children and treatments, in the slum population of Dhaka city, Bangladesh. 1500 households in three slum communities were included in a cross‐sectional survey. Reported death rates in the households per 1000 children (0–107 months) within the last year from the interview were 20.5 for boys and 27.0 for girls. More girls than boys died in infancy (age < 12 months). The most frequent reported causes of deaths were tetanus in infancy and diarrhoea among children aged ≤ 12 months. Vaccination coverage (DPT, polio, measles and BCG) was 73% for children < 3 years of age. The results showed that gender difference in mortality may have been influenced by the patterns of treatment received during sickness and the choice of treatment was determined by the financial ability of the households. Household income, children's vaccinations, TT immunization of mothers and personal cleanliness appeared to be significantly associated with child mortality. Despite the relatively high vaccination coverage for this population, child mortality remained alarmingly high, indicating that socioeconomic and environmental conditions must be improved to substantially reduce morbidity and mortality in this population.
Treatment of two patients with diffuse cutaneous leishmaniasis caused by Leishmania mexicana modifies the immunohistological profile but not the disease outcome
Authors: Salaiza‐Suazo Norma , Volkow Patricia , Pérez Tamayo Ruy , Moll Heidrun , Gillitzer Reinhard , Pérez‐Torres Armando , Pérez‐Montfort Ruy , Domínguez Jose Delgado , Velasco‐Castrejón Oscar , Crippa Marco , Becker Ingeborg
Published: March 2003

Summary Two patients with diffuse cutaneous leishmaniasis caused by Leishmania mexicana were treated with two leishmanicidal drugs (pentamidine and allopurinol) combined with recombinant interferon‐γ restoring Th‐1 favouring conditions in the patients. Parasites decreased dramatically in the lesions and macrophages diminished concomitantly, while IL‐12‐producing Langerhans cells and interferon‐γ– producing NK and CD8 + lymphocytes increased in a reciprocal manner. The CD4+/CD8 + ratio in the peripheral blood normalized. During exogenous administration of interferon‐γ the parasites' capacity to inhibit the oxidative burst of the patients' monocytes was abolished. Even though Th‐1‐favouring conditions were restored, both patients relapsed two months after therapy was discontinued. We conclude that the tendency to develop a disease‐promoting Th‐2 response in DCL patients is unaffected by, and independent of, parasite numbers. Even though intensive treatment in DCL patients induced Th‐1 disease restricting conditions, the disease‐promoting immunomodulation of few persistent Leishmania sufficed to revert the immune response.
Economic evaluation of parasitic diseases: A critique of the internal and external validity of published studies
Authors: Walker Damian , Fox‐Rushby Julia
Published: March 2003

SummaryIt was estimated that in 1990, major parasitic diseases accounted for 11.7% of the disease burden from communicable disease. As advances in the prevention, diagnosis and treatment of parasitic diseases are made and implemented, there is a growing economic literature to help decision‐makers choose the most efficient control method. The aim of this paper is to identify, describe and analyse the available published data on the efficiency of control strategies against parasitic diseases. Internal validity is assessed through the quality of economic evaluations over time using a series of standard questions, and external validity is assessed in terms of the potential to extrapolate results to other settings. This leads to a discussion of the legitimacy and feasibility of pooling data or results from studies for priority setting in the health sector, resulting in three recommendations: to increase the coverage of economic evaluations for parasitic diseases and types of interventions; to improve the internal validity of studies through guidelines and review procedures; and to explore the external validity of research results by examining their predictive validity across settings.
Pregnancy and HIV‐1 incidence in 178 married couples with discordant HIV‐1 serostatus: additional experience at an HIV‐1 counselling centre in the Democratic Republic of the Congo
Authors: Ryder R. W. , Kamenga C. , Jingu M. , Mbuyi N. , Mbu L. , Behets F.
Published: March 2003

Summary To determine the effect of an HIV‐1 counselling programme on rates of HIV‐1 infection and pregnancy in a large group of married couples in Kinshasa, DRC with discordant HIV‐1 infection status, we conducted a baseline cross‐sectional HIV‐1 seroprevalence study in two large Kinshasa businesses. We identified 178 married couples (mean duration of marriage = 12.3 years) with discordant HIV‐1 serostatus (92 M+F‐/86 M‐F+). Seroincidence and pregnancy rates were observed during 310 person‐years of follow‐up (PYFU). The 92 M+F‐ couples had an HIV‐1 incidence of 3.7/100 PYFU and a pregnancy rate of 8.6/100. The 86 M‐F+ couples had a pregnancy rate of 6.8/100 PYFU and an HIV‐1 incidence of 6.8/100 PYFU. Couples seeking to have children but minimize their HIV‐1 transmission risk frequently had unprotected sex only during the woman's perceived monthly fertility period. This strategy resulted in the birth of 24 live‐born children and only one (4%; 95% CL = 0.0–21.6%) new HIV infection in couples having a child. Only 1 of 6 women who developed HIV‐1 infection (16.7%; 95 C.L. = 0–40.4%) became pregnant. While seronegative men had more extramarital sex once their wives' positive HIV‐1 infection status became known, most of these episodes involved safe sex. Divorce was rare. This study provides additional information concerning issues of safe sex in married couples with discordant HIV‐1 infection status, the dynamics of HIV transmission within couples and the effect of serostatus notification on the marriage and on intramarital and extramarital sexual behaviour in Kinshasa, Congo.
Editorial: The Global Programme to Eliminate Lymphatic Filariasis
Authors: Ottesen Eric A.
Published: March 2003

Summary Ten years ago, no one foresaw that in the year 2000 there would be a Global Programme to Eliminate Lymphatic Filariasis (GPELF) that is already 2 years old, active in 18 of the 80 endemic countries, and operating under a wholly new paradigm in public health – a paradigm affirming that public/private sector partnerships are essential in sharing both responsibilities and responses to global health problems. What has driven the LF Elimination Programme to this point? Where it is now headed? What will be required to sustain its momentum? What will its impact be? These are the issues addressed below.
Dengue transmission risk maps of Argentina
Authors: Carbajo Aníbal Eduardo , Schweigmann Nicolás , Curto Susana Isabel , De Garín Alicia , Bejarán Rubén
Published: March 2003

Dengue is an emerging disease that has become important in Argentina because of its vector’s presence (Aedes aegypti) and its endemicity in neighbouring countries. Thematic maps were built for Argentina considering four main factors: population susceptibility to dengue virus infection (population density); entrance of the virus from endemic countries (main roads and airports); conditions for the vector (urbanization, altitude, minimum, maximum and mean daily temperatures) and virus extrinsic incubation period (EIP) completion in the mosquito before its death. EIP duration was modelled with a temperature‐dependent function and considering life expectancies of 10, 15 and 20 days for the adult mosquito. The results show maximum risk of dengue transmission in the northern and north‐eastern part of the country year‐round and in the centre during the summer. Although life expectancy of the adult mosquito has a considerable influence on EIP completion, the north‐east to south‐west decreasing gradient is maintained. Assuming 20‐day life expectancy, the EIP would be completed in almost any region of the country; whereas with 15‐day life expectancy it would be limited to vector distribution area, and at 10 days it would be restricted to the northern extreme of the country.
Viewpoint: Medical infertility care in low income countries: the case for concern in policy and practice
Authors: Van Zandvoort Helma , De Koning Korrie , Gerrits Trudie
Published: March 2003

Based on published, ‘grey’ and anecdotal information, this paper explores some aspects of infertility, its medical treatment and their burden in poor countries. Many cases of infertility result from sexually transmitted infections (STI) and unsafe abortion and there is no doubt that their prevention and adequate treatment are of utmost importance, especially as effective infertility treatment, if any, comes at a high price for the consumer, materially as well as physically. Medical infertility interventions are apt to fail a free market of provision because of major information asymmetry. This renders patients in low‐resource countries prone to exploitation, potentially damaging practices and waste of their savings. The authors argue that in countries struggling with limited funds and a range of pressing public health problems, public investment in infertility treatment should not have priority. But governments should take an active role in quality control and regulation of treatment practice, as well as invest in counseling skills for lower‐level reproductive health staff to achieve rational referral of patients.
Modelling parasite drug resistance: lessons for management and control strategies
Authors: Hastings Ian M.
Published: March 2003

Mathematical models of the evolution of drug resistance in infectious diseases are predominantly concentrated in three main areas: antimalarial, antibiotic and anthelmintic resistance. There appears to be little or no cross‐reference between them. This literature was examined to identify factors that influence the evolution of drug resistance irrespective of the species and drug under study. The aim is to provide non‐technical readers with a basic qualitative understanding of the issues and pitfalls involved in designing drug treatment regimens to minimize the evolution of resistance. The principal factors determining the rate at which resistance evolves appear to be (i) the starting frequency of resistance, (ii) the level and pattern of drug use, (iii) the drug’s pharmacokinetic properties, (iv) the number of genes required to encode resistance, (v) the level of sexual recombination in the parasite population, (vi) intrahost dynamics and, in particular, whether ‘crowding’ effects are present, (vii) the genetic basis of resistance and (viii) the number of individual parasites in an infection. The relative importance of these factors depends on the biology of the organisms under consideration and external factors such as the extent to which the infrastructure of health care delivery constrains the practicalities of drug regimens.
Two cases of autochthonous Plasmodium falciparum malaria in Germany with evidence for local transmission by indigenous Anopheles plumbeus
Authors: Krüger Andreas , Rech Andreas , Su Xin‐Zhuan , Tannich Egbert
Published: March 2003

Autochthonous Plasmodium falciparum malaria (PFM) in Central Europe has been reported repeatedly, transmission of the parasite being attributed to blood transfusion or imported P. falciparum‐infected vectors. We report two cases of PFM in German children without travel history to malaria‐endemic areas. Both infections occurred during a stay in a hospital where a child from Angola with chronic P. falciparum infection was hospitalized at the time. Known routes of transmission, such as imported mosquitoes or blood transfusion, were very unlikely or could be excluded, whereas evidence was obtained for transmission by the indigenous mosquito species Anopheles plumbeus.
Editorial: Does Brussels listen? European health systems research in developing countries at the edge of extinction
Authors: Kroeger Axel , Falkenberg Torkel , Tomson Goran , Sen Kasturi , Diesfeld Hans Jochen , Dujardin Bruno , Tang Shenglan , Van der Stuyft Patrick
Published: March 2003

Research into health systems all over the world has contributed to the development of new disease control strategies, modernized hospital and outpatient care, alternative financing mechanisms, cost‐effective interventions and monitoring tools which resulted in improved delivery of care and public health services. But financing of such research is a problem in many European countries – particularly when the study is to be carried out outside the European Union – as it does not fall into the classical categories of basic science, medical science or development of drugs and vaccines and may not have an immediate impact on European health services. In view of this, a European programme for strengthening health systems research in developing countries (INCO‐DEV) was set up by the European Commission in Brussels in 1983 which was integrated into the Science and Technology for Development programme on an increasing budget. For two decades it has facilitated high quality health systems research influencing health policies worldwide. Examples for INCO‐funded projects are given below.
The use of the paediatric tuberculosis score chart in an HIV‐endemic area
Authors: Van Rheenen Patrick
Published: March 2003

BACKGROUND
 Diagnosing tuberculosis (TB) in a human immunodeficiency virus (HIV)‐endemic area is extremely difficult, as the clinical symptoms of HIV‐seropositive children can be easily confounded with TB. The paediatric tuberculosis score chart (TSC) was developed for resource‐poor countries and its use continues to be promoted despite the fact that this scoring system has not been evaluated in countries with a high HIV prevalence.

OBJECTIVE
 To assess the utility of the TSC in an HIV‐endemic area.

METHOD
 A prospective cohort study conducted between January and December 1999 at St Theresa's Mission Hospital, Copperbelt Province, Zambia. Results of the TSC (TB score) were compared with the results of a diagnostic algorithm, incorporating sputum smear microscopy, culture and polymerase chain reaction of Mycobacterium tuberculosis, tuberculin skin test, chest X‐ray and histology eventually.

RESULTS
 A total of 147 children were enrolled in the study. On the basis of HIV‐serology and clinical findings they were divided into four groups: children with TB (23 HIV‐seropositive; 52 HIV‐seronegative), 21 HIV‐infected children without TB and 51 HIV‐seronegative children without TB. The differences in TB scores between the groups were not significant. The sensitivity of the TSC to diagnose TB in this study was 88%; but the specificity was only 25%.

CONCLUSION
 The TSC should not be used as a diagnostic tool in countries with a high HIV prevalence. The low specificity of this scoring system leads to overdiagnosis of TB and unnecessary use of costly, antituberculous drugs. New tools for TB diagnosis in children in HIV‐endemic areas are urgently needed.
TB control, poverty, and vulnerability in Delhi, India
Authors: Singh V. , Jaiswal A. , Porter J. D. H. , Ogden J. A. , Sarin R. , Sharma P. P. , Arora V. K. , Jain R. C.
Published: March 2003

The Revised National Tuberculosis Control Programme (RNTCP), based on the World Health Organization's DOTS strategy,* was introduced in India in the mid‐1990s. This paper reports the findings from operational research studies in two pilot sites in New Delhi from 1996 to 1998. A variety of operational research methods were used, including semi‐structured interviews, focus group discussions, non‐participant observations and collection of data from the tuberculosis registers. The cure rates for the clinics were 71 and 75% with a default rate of 6 and 11%, respectively. An important finding was that health workers screened patients to determine their ability to conform to the direct observation of treatment element of the RNTCP. If the health worker was confident that the patient would comply and/or be easy to trace in the community in the event of `default', they were provided with short‐course treatment under the RNTCP. Other patients, largely those who were in absolute poverty, socially marginalized, itinerant labourers, poorly integrated in the city, were put on standard tuberculosis (TB) treatment as for the previous National TB Programme. The programme was evidently excluding the most vulnerable from the best available care. These findings demonstrate the potential dangers of target‐driven programmes where there is an absence of support to both frontline health workers and patients. The paper also highlights the importance of operations research in helping to identify problems within TB programmes.
Epidemiology of leprosy on five isolated islands in the Flores Sea, Indonesia
Authors: Bakker Mirjam I. , Hatta Mochammad , Kwenang Agnes , Klatser Paul R. , Oskam Linda
Published: March 2003

We conducted a population‐based survey on five small islands in South Sulawesi Province (Indonesia) to collect baseline data previous to a chemoprophylactic intervention study aiming at interrupting the transmission of Mycobacterium leprae. Here we describe the present leprosy epidemiology on these geographically isolated islands. Of the 4774 inhabitants living in the study area 4140 were screened for leprosy (coverage: 87%). We identified 96 leprosy patients (85 new and 11 old patients), representing a new case detection rate (CDR) of 205/10 000 and a prevalence rate of 195/10 000. CDRs were similar for males and females. Male patients were more often classified as multibacillary (MB) than women. Of the new patients, 33 (39%) were classified as MB, 16 (19%) as paucibacillary (PB) 2–5 lesions and 36 (42%) as PB single lesion. In this area of high leprosy endemicity leprosy patients were extensively clustered, i.e. not equally distributed among the islands and within the islands among the houses.