bluuebunny/crossref_metadata_2025_split huggingface dataset:
Developmental and light effects on the accumulation of FtsH protease in Arabidopsis chloroplasts – implications for thylakoid formation and photosystem II maintenance
Authors: Zaltsman Adi , Feder Ari , Adam Zach 
Published: May 2005

SummaryThe chloroplast ATP‐dependent metalloprotease FtsH is involved in the degradation of unassembled proteins, the repair of photosystem II (PSII) from photoinhibition, and, apparently, the formation of thylakoids. In Arabidopsis, it is encoded by a family of 12 genes. However, the products of only four of them, FtsH1, 2, 5 and 8, have been found in chloroplasts to date. Mutations in two of these, FtsH2 and 5, demonstrate a visible phenotype of variegated leaves, with the phenotype of the FtsH2 mutant being more pronounced. Moreover, the degree of variegation appears to be dependent on developmental stage and environmental factors, suggesting an intricate relationship between the different gene products. To explore this, developmental and light effects on the accumulation of FtsH protease were studied in wild‐type (WT) and FtsH2‐mutant plants. Whereas cotyledons of the mutant were indistinguishable from those of the WT, the first true leaves were almost completely white. Subsequent leaves contained increasing proportions of green sectors. Analysis of the mRNA of the four FtsH genes, in cotyledons, first and second leaves of WT and mutant plants, revealed that: (i) transcript level increases during development, and (ii) transcript level in the mutant is higher than in the WT. FtsH protein level in the mutant was ca. 50% of that found in the WT, whereas the levels of other thylakoid proteins were the same. In individual leaves, the level of FtsH protein increased during development as well. Exposure of seedlings to different light intensities did not affect the degree of variegation, suggesting that it is due to a defect in chloroplast development rather than photobleaching. Examination of FtsH protein during exposure to high light revealed a decrease in its level, concomitant with a decrease in PSII potential, suggesting that the kinetics of photoinhibition reflects not only photodamage to PSII and induction of protective mechanisms, but also a decrease in repair capacity due to a reduction in the level of FtsH protease.
The DOF protein, SAD, interacts with GAMYB in plant nuclei and activates transcription of endosperm‐specific genes during barley seed development
Authors: Diaz Isabel , Martinez Manuel , Isabel‐LaMoneda Ines , Rubio‐Somoza Ignacio , Carbonero Pilar 
Published: May 2005

SummaryThe DOF protein, SAD, previously shown to be a transcriptional activator in barley aleurone cells upon seed germination, also has an important role in gene regulation during endosperm development. mRNA was detected in early (10 days after flowering) developing barley seeds where it accumulated in the starchy endosperm, aleurone cells, nucellar projection, vascular tissues and the immature embryo, as shown by RT‐PCR and in situ hybridization analyses. The SAD protein, expressed in bacteria, binds to oligonucleotides containing the prolamine box, 5′‐A/TAAAG‐3′sequence, derived from the promoter regions of the endosperm‐specific genes Hor2 and Itr1, encoding a B‐hordein and trypsin‐inhibitor BTI‐CMe, respectively. SAD competed for the same binding sites with another endosperm‐expressed DOF protein, BPBF. Transient expression experiments in co‐bombarded developing endosperms demonstrated that SAD trans‐activated transcription from Hor2 and Itr1 promoters through binding to the intact DOF motifs. When the two DOF factors are co‐bombarded together an additive effect was observed upon the expression of the Itr1 gene. In‐frame fusion of the Sad ORF to the reporter green fluorescent protein gene directs the fluorescence expression to the nucleus in transiently transformed onion epidermal layers. The visualization of fluorescence in the nucleus of onion cells, using the bimolecular fluorescent complex (BiFC) approach, has shown the in vivo interaction between SAD and the R2R3MYB protein GAMYB. The interaction in plant cells has also been documented for the DOF protein BPBF and GAMYB, but nuclear interaction could not be detected between BPBF and SAD by this procedure.
Global transcript profiling of primary stems from Arabidopsis thaliana identifies candidate genes for missing links in lignin biosynthesis and transcriptional regulators of fiber differentiation
Authors: Ehlting Jürgen , Mattheus Nathalie , Aeschliman Dana S. , Li Eryang , Hamberger Britta , Cullis Ian F. , Zhuang Jun , Kaneda Minako , Mansfield Shawn D. , Samuels Lacey , Ritland Kermit , Ellis Brian E. , Bohlmann Jörg , Douglas Carl J. 
Published: May 2005

SummaryDifferent stages of vascular and interfascicular fiber differentiation can be identified along the axis of bolting stems in Arabidopsis. To gain insights into the metabolic, developmental, and regulatory events that control this pattern, we applied global transcript profiling employing an Arabidopsis full‐genome longmer microarray. More than 5000 genes were differentially expressed, among which more than 3000 changed more than twofold, and were placed into eight expression clusters based on polynomial regression models. Within these, 182 upregulated transcription factors represent candidate regulators of fiber development. A subset of these candidates has been associated with fiber development and/or secondary wall formation and lignification in the literature, making them targets for functional studies and comparative genomic analyses with woody plants. Analysis of differentially expressed phenylpropanoid genes identified a set known to be involved in lignin biosynthesis. These were used to anchor co‐expression analyses that allowed us to identify candidate genes encoding proteins involved in monolignol transport and monolignol dehydrogenation and polymerization. Similar analyses revealed candidate genes encoding enzymes that catalyze missing links in the shikimate pathway, namely arogenate dehydrogenase and prephenate aminotransferase.
The nuclear gene HCF107 encodes a membrane‐associated R‐TPR (RNA tetratricopeptide repeat)‐containing protein involved in expression of the plastidial psbH gene in Arabidopsis
Authors: Sane Aniruddha P. , Stein Bernhard , Westhoff Peter 
Published: May 2005

SummaryExpression of the genes of plastidial psbB operon (psbB‐psbT‐psbH‐petB‐petD) involves multiple processing events and formation of several mono‐, di‐ and multi‐cistronic transcripts which are further regulated by differential stability and expression. Here we describe the identification of the HCF107 gene that is involved in the 5′‐end processing/stability and/or translation of the psbH gene and in the translation of the psbB gene. HCF107 is an RNA‐TPR‐containing protein with 11 RTPRs that are tandemly arranged. A single mutation in the third RTPR that changes a conserved alanine residue to a threonine affects both 5′‐end‐processed psbH transcript accumulation as well as psbB translation, resulting in disruption of PSII and seedling lethal plants. The protein is localized to the plastid membranes and is present as part of a multi‐subunit complex in the range of 60–190 and 600–800 kDa. HCF107 thus represents a new member of the growing helical repeat family of proteins that seem to play a gene‐specific role in regulating plastidial gene expression and biogenesis.
EMBRYONIC FACTOR 1 encodes an AMP deaminase and is essential for the zygote to embryo transition in Arabidopsis
Authors: Xu Jun , Zhang Hai‐Ying , Xie Cong‐Hua , Xue Hong‐Wei , Dijkhuis Paul , Liu Chun‐Ming 
Published: May 2005

SummaryFusion of the egg and the sperm cells in plants produces a zygote that develops into an embryo. Screening of ethyl methanesulfonate‐mutagenized populations of Arabidopsis led to the identification of EMBRYONIC FACTOR 1 (FAC1), a locus that gives a zygote‐lethal phenotype when mutated. The FAC1 gene was identified by positional cloning and confirmed by a genetic complementation test against a T‐DNA insertion allele. It encodes an AMP deaminase (AMPD) that is known in human and yeast to convert AMP to IMP to maintain the energy potential. Expression of FAC1 in a yeast AMPD mutant after removal of its N‐terminal putative transmembrane domain complemented the mutant phenotype, suggesting a functional conservancy but a structural divergence through evolution. Although a low level of FAC1 expression was observed in all organs tested, using a reporter construct we observed a significantly increased FAC1 expression in the zygote, early embryo and endosperm. Furthermore, during somatic embryogenesis, a high level of FAC1 expression was observed in developing embryos including putative embryogenic cells. FAC1, therefore, represents one of the earliest expressed genes known in plants. It may act through AMP depletion to provide sufficient energy for the zygote to proceed through development.
Pesticide poisoning in south India: opportunities for prevention and improved medical management
Authors: Srinivas Rao CH. , Venkateswarlu V. , Surender T. , Eddleston Michael , Buckley Nick A. 
Published: June 2005

SummaryObjective  Warangal district in Andhra Pradesh, southern India, records >1000 pesticide poisoning cases each year and hundreds of deaths. We aimed to describe their frequency and distribution, and to assess quality of management and subsequent outcomes from pesticide poisoning in one large hospital in the district.Methods  We reviewed data on all patients admitted with pesticide poisoning to a district government hospital for the years 1997 to 2002. For 2002, details of the particular pesticide ingested and management were abstracted from the medical files.Findings  During these 6 years, 8040 patients were admitted to the hospital with pesticide poisoning. The overall case fatality ratio was 22.6%. More detailed data from 2002 revealed that two‐thirds of the patients were <30 years old, 57% were male and 96% had intentionally poisoned themselves. Two compounds, monocrotophos and endosulfan, accounted for the majority of deaths with known pesticides in 2002. Low fixed‐dose regimens were used in the majority of cases for the most commonly used antidotes (atropine and pralidoxime). Inappropriate antidotes were also used in some patients.Conclusions  It is likely that these findings reflect the situation in many rural hospitals of the Asia Pacific region. Even without an increase in resources, there appear to be significant opportunities for reducing mortality by better medical management and further restrictions on the most toxic pesticides.
Review: The phenothiazinium chromophore and the evolution of antimalarial drugs
Authors: Wainwright Mark , Amaral Leonard 
Published: June 2005

SummaryThe phenothiazinium salt methylene blue [3,7‐bis(dimethylamino)phenothiazinium chloride] is the oldest known synthetic antimalarial drug, its clinical efficacy having been reported in 1891. The role of methylene blue in the evolution of the modern antimalarial armoury is often unappreciated, yet it can be linked directly to standard drugs such as chloroquine and its congeners. Also, in the face of increasing plasmodial resistance to modern antimalarials, phenothiazinium derivatives have again featured as lead compounds in drug research. The precise mode of action of methylene blue and its commercial analogues against Plasmodium spp. remains a cause for conjecture, having been variously described as nucleic acid intercalation, food vacuole basification, parasite redox cycle interference and haem polymerization inhibition. That the activity of the series may be due to more than one route – i.e. a multifactorial activity – underlines the utility of these compounds in antimalarial research either as single drugs or as adjuvants (partners in a drug combination), particularly in the face of resistant parasitic strains.
Season, fever prevalence and pyrogenic threshold for malaria disease definition in an endemic area of Mali
Authors: Dicko Alassane , Mantel Carsten , Kouriba Boureima , Sagara Issaka , Thera Mahamadou A. , Doumbia Seydou , Diallo Mouctar , Poudiougou Belco , Diakite Mahamadou , Doumbo Ogobara K. 
Published: June 2005

SummaryBackground  Modelling malaria parasitaemia as function of fever has been proposed as best alternative to estimate the attributable fraction of malaria fever and the sensitivity and specificity of different case definitions of malaria disease.Objectives  To determine the prevalence of fever and its relation to malaria parasitaemia and to establish a pyrogenic threshold for malaria disease in the area.Methods  We conducted two cross‐sectional surveys in children of 6 months to 9 years of age (2434 during the rainy season of 1993 and 2353 during the dry season of 1994) randomly selected from 21 areas of Bandiagara district, Mali.Results  The relationship between fever and Plasmodium falciparum parasitaemia depends strongly on the season, thus affecting the malaria‐attributable fraction of fever cases and the sensitivity and specificity of malaria case definitions. The overall proportion of fever attributable to malaria parasitaemia was 33.6% during the rainy season and 23.3% during the dry season, with the highest proportion occurring among the youngest children. The cut‐off value, where the sensitivity curve crosses the specificity curve, was around 3200 pf/μl for all age categories during the rainy season and 200 pf/μl during the dry season.Conclusions  Malaria remains a main cause of fever in this area of Mali. The pyrogenic threshold of parasitaemia depends strongly on the season, and different cut‐off levels of parasitaemia should be used during the two seasons to define malaria cases in this area.
Short Communication: Palestinian infantile visceral leishmaniasis caused by a genetic variant of Leishmania infantum belonging to a new zymodeme
Authors: Bader Khaldoun A. , Schnur Lionel F. , Nasereddin Abedelmajeed , Pratlong Francine , Dedet Jean‐Pierre , Shaheen Loay , Yousef Obaida , Greenblatt Charles L. 
Published: June 2005

SummaryThe parasites causing a Palestinian case of infantile visceral leishmaniasis (IVL) and those from four dogs from the Jenin District were identified serologically, biochemically and molecular biologically as Leishmania infantum, showing dogs act as a reservoir. The strain from the human case was distinct because of its unique 200‐bp kDNA‐polymerase chain reaction (PCR) component in its restriction fragment length polymorphism (RFLP) profile after digestion with the endonuclease RsaI, and by the electrophoretic mobility of its malate dehydrogenase (MDH140), designating it the reference strain of a new zymodeme of L. infantum, MON‐281.
Molecular tracking of the lineage of strains of Vibrio cholerae O1 biotype El Tor associated with a cholera outbreak in Andaman and Nicobar Islands, India
Authors: Roy Subarna , Dutta Basabjit , Ghosh Asit Ranjan , Sugunan A. P. , Nandy Ranjan Kumar , Bhattacharya Sujit Kumar , Sehgal Subhash C. 
Published: June 2005

SummaryA large outbreak of acute watery diarrhoea involving all age groups of mongoloid tribal aborigines occurred during October–November, 2002 in the Nancowry group of Andaman and Nicobar Islands in the Indian Ocean. Twenty‐one of the 67 stool samples from 67 patients were positive for toxigenic Vibrio cholerae O1, serotype Ogawa biotype El Tor, which showed striking similarity in its antibiogram with some of the strains of V. cholerae O1 Serotype Ogawa biotype El Tor isolated in Kolkata. The Nancowry and Kolkata isolates were compared with molecular tools involving random amplified polymorphic DNA (RAPD) fingerprinting, ribotyping and pulsed‐field gel electrophoresis (PFGE). RAPD fingerprinting and ribotyping techniques revealed that all the V. cholerae strains associated with the outbreak in these islands were clonal in nature and identical to a population of isolates obtained from Kolkata since 1993. PFGE could discriminate within these Kolkata isolates further and established that a particular subtype of this population reached the remote Nancowry islands and was responsible for the outbreak.
Associations between frequencies of a susceptible TNF‐α promoter allele and protective α‐thalassaemias and malaria parasite incidence in Vanuatu
Authors: Ubalee R. , Tsukahara T. , Kikuchi M. , Lum J. K. , Dzodzomenyo M. , Kaneko A. , Hirayama K. 
Published: June 2005

SummaryTumour necrosis factor‐alpha (TNF‐α) is one of the key cytokines that influence the pathology of microbial infections. The genetic susceptibility to severe forms of falciparum malaria is differentially associated with TNF‐α promoter gene polymorphisms (TNFP alleles). In a previous study, we identified a TNFP‐allele characterized by a C to T transition at position −857 (TNFP‐D allele) as a marker for susceptibility to cerebral malaria in Myanmar. The frequencies of TNFP alleles on six islands of Vanuatu, Melanesia (South‐west Pacific) were estimated to investigate whether malaria selection pressure on this susceptibility marker has influenced its prevalence. Within the archipelago of Vanuatu there is a decreasing cline of parasite incidence from North to South. Of the four alleles of the TNFP gene detected in Vanuatu, the TNFP‐D allele frequencies were inversely correlated with the parasite incidence of islands; TNFP‐D varied from 0.55 on the island with the lowest parasite incidence to 0.26 on the island with the highest parasite incidence (r = −0.855, P = 0.03). We also observed a significant correlation between the frequencies of α‐thalassaemia alleles, thought to protect against malaria and parasite incidence in the same populations. These data are consistent with a previously reported correspondence between the frequencies of glucose 6‐phosphate dehydrogenase (G6PD) deficiency and parasite incidences on the islands of Vanuatu (Kaneko et al. 1998) and indicate that the degree of malaria endemicity has influenced the allele frequencies of at least three loci that confer both susceptibility (TNFP‐D) and protection (α‐thalassaemias and G6PD deficiency).
A randomized, placebo‐controlled, double‐blind trial on sulfadoxine–pyrimethamine alone or combined with artesunate or amodiaquine in uncomplicated malaria
Authors: Mockenhaupt Frank P. , Ehrhardt Stephan , Dzisi Stephen Y. , Teun Bousema J. , Wassilew Nasstasja , Schreiber Jonas , Anemana Sylvester D. , Cramer Jakob P. , Otchwemah Rowland N. , Sauerwein Robert W. , Eggelte Teunis A. , Bienzle Ulrich 
Published: June 2005

SummaryThe therapeutic efficacy of sulfadoxine–pyrimethamine (SP) alone, SP plus amodiaquine (AQ), and SP plus artesunate (AS) was assessed in a randomized, placebo‐controlled, and double‐blind trial among 438 children with uncomplicated Plasmodium falciparum malaria in northern Ghana. Clinical and parasitological responses were monitored for 28 days following treatment; 86%, 98% and 97% of SP‐, SP + AQ‐, and SP + AS‐treated patients achieved adequate clinical and parasitological response (ACPR) within 2 weeks, respectively. Parasite clearance was better with SP + AS than with SP or SP + AQ treatment but re‐infections were more common. Polymerase chain reaction (PCR)‐corrected rates of ACPR at day 28 were 72.2% for SP, 94.1% for SP + AQ (P < 0.0001), and 94.5% for SP + AS (P < 0.0001). Gametocyte prevalence and density 1 week after treatment were highest in children treated with SP, and lowest in patients receiving SP + AS. No severe adverse events attributable to study medication were observed. In northern Ghana, more than one of four children suffered SP treatment failure within 4 weeks. Both SP + AQ and SP + AS are efficacious alternative therapeutic options in this region. Although SP + AS and SP + AQ treatments have virtually identical cure rates, rapid parasite clearance and pronounced gametocidal effects are the advantages of the former, whereas cost and a lower rate of late re‐infections are those of the latter.
A World Health Organization International Standard for hepatitis A virus RNA nucleic acid amplification technology assays
Authors: Saldanha J. , Heath A. , Lelie N. , Pisani G. , Yu M.‐Y. ,   the Collaborative Study Group
Published: June 2005

Background and Objectives Sixteen laboratories from 10 different countries participated in an international collaborative study to evaluate candidate materials as the first World Health Organization (WHO) International Standard for hepatitis A virus (HAV) RNA nucleic acid amplification technology (NAT) assays.Materials and Methods Five candidate materials were analysed in this study: materials AA and BB were lyophilized, while materials CC, DD and EE were liquid preparations. Samples were diluted in pooled plasma or in pooled cryo‐poor plasma (sample EE). Serial dilutions of the candidate materials were tested by each laboratory in four independent assays and the results were analysed statistically.Results The mean log10‘equivalents’ per ml were 5·29 for sample AA, 5·07 for sample BB, 4·99 for sample CC, 5·40 for sample DD and 4·08 for sample EE.Conclusions Based on the results of this study, sample AA was established as the first International Standard for HAV RNA NAT assays at the WHO Expert Committee on Biological Standardizaton (ECBS) meeting held in February 2003. The code number of this preparation is 00/560 and the potency, based on the study, is 100 000 International Units (IU)/ml.
Interlaboratory comparison of red‐cell ATP, 2,3‐diphosphoglycerate and haemolysis measurements
Authors: Hess J. R. , Kagen L. R. , Van Der Meer P. F. , Simon T. , Cardigan R. , Greenwalt T. J. , AuBuchon J. P. , Brand A. , Lockwood W. , Zanella A. , Adamson J. , Snyder E. , Taylor H. L. , Moroff G. , Hogman C. 
Published: June 2005

Background and Objectives  Red blood cell (RBC) storage systems are licensed based on their ability to prevent haemolysis and maintain RBC 24‐h in vivo recovery. Preclinical testing includes measurement of RBC ATP as a surrogate for recovery, 2,3‐diphosphoglycerate (DPG) as a surrogate for oxygen affinity, and free haemoglobin, which is indicative of red cell lysis. The reproducibility of RBC ATP, DPG and haemolysis measurements between centres was investigated.Materials and Methods  Five, 4‐day‐old leucoreduced AS‐1 RBC units were pooled, aliquotted and shipped on ice to 14 laboratories in the USA and European Union (EU). Each laboratory was to sample the bag twice on day 7 and measure RBC ATP, DPG, haemoglobin and haemolysis levels in triplicate on each sample. The variability of results was assessed by using coefficients of variation (CV) and analysis of variance.Results  Measurements were highly reproducible at the individual sites. Between sites, the CV was 16% for ATP, 35% for DPG, 2% for total haemoglobin and 54% for haemolysis. For ATP and total haemoglobin, 94 and 80% of the variance in measurements was contributed by differences between sites, and more than 80% of the variance for DPG and haemolysis measurements came from markedly discordant results from three sites and one site, respectively. In descending order, mathematical errors, unvalidated analytical methods, a lack of shared standards and fluid handling errors contributed to the variability in measurements from different sites.Conclusions  While the methods used by laboratories engaged in RBC storage system clinical trials demonstrated good precision, differences in results between laboratories may hinder comparative analysis. Efforts to improve performance should focus on developing robust methods, especially for measuring RBC ATP.