bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular properties of the putative nitrogen sensor PII from Arabidopsis thaliana
Authors: Smith Catherine S. , Weljie Aalim M. , Moorhead Greg B. G. 
Published: March 2003

SummaryAlthough the signal sensing protein PII is well known to play a central role in bacterial nitrogen metabolism, the structure and function of PII in plants remains only partially understood. Comparative modeling was undertaken based on the high degree of amino acid identity between Escherichia coli and Arabidopsis PII. The mature Arabidopsis PII predicted structure superimposes very well onto the E. coli PII structure (Cα root mean square deviation < 0.4 Å). The model of the highly conserved T‐loop suggests a molecular mechanism by which the plant PII may regulate putative post‐translational modification in response to metabolite binding. Consistent with the presence of key conserved residues necessary for trimer formation, gel filtration showed the oligomeric structure of Arabidopsis thaliana PII to be a homotrimer. We have demonstrated that Arabidopsis PII binds to the small molecules, ATP, ADP, 2KG, and with lesser affinity to OAA, using isothermal titration calorimetry. We have determined the metabolite dissociation constants and compared these with known physiological concentrations of these metabolites in the plant to identify the Arabidopsis PII effector molecules and their possible roles. We predict that the plant PII is likely continually bound by ATP, and its ligand‐bound state only varying with respect to the degree of 2KG binding. Based on our in vitro binding studies, the function of plant PII as a 2KG sensor is suggested.
The OsTB1 gene negatively regulates lateral branching in rice
Authors: Takeda Taito , Suwa Yuko , Suzuki Makoto , Kitano Hidemi , Ueguchi‐Tanaka Miyako , Ashikari Motoyuki , Matsuoka Makoto , Ueguchi Chiharu 
Published: March 2003

SummaryAlthough the shoot apical meristem (SAM) is ultimately responsible for post‐embryonic development in higher plants, lateral meristems also play an important role in determining the final morphology of the above‐ground part. Axillary buds developing at the axils of leaves produce additional shoot systems, lateral branches. The rice TB1 gene (OsTB1) was first identified based on its sequence similarity with maize TEOSINTE BRANCHED 1 (TB1), which is involved in lateral branching in maize. Both genes encode putative transcription factors carrying a basic helix–loop–helix type of DNA‐binding motif, named the TCP domain. The genetic locus of OsTB1 suggested that OsTB1 is a real counterpart of maize TB1. Transgenic rice plants overexpressing OsTB1 exhibited markedly reduced lateral branching without the propagation of axillary buds being affected. We also demonstrated that a rice strain carrying a classical morphological marker mutation, fine culm 1 (fc1), contain the loss‐of‐function mutation of OsTB1 and exhibits enhanced lateral branching. Expression of OsTB1, as examined with a putative promoter–glucuronidase (GUS) gene fusion, was observed throughout the axillary bud, as well as the basal part of the shoot apical meristem, vascular tissues in the pith and the lamina joint. Taking these data together, we concluded that OsTB1 functions as a negative regulator for lateral branching in rice, presumably through expression in axillary buds.
Cell cycle‐dependent association ofArabidopsisactin‐related proteins AtARP4 and AtARP7 with the nucleus
Authors: Kandasamy Muthugapatti K. , McKinney Elizabeth C. , Meagher Richard B. 
Published: March 2003

SummaryArabidopsisencodes at least eight actin‐related proteins (ARPs) most of which have orthologs in other distant organisms. To gain insight into the role of ARPs in plants, we have examined the spatial expression and subcellular distribution of two highly divergentArabidopsisARPs, AtARP4 and AtARP7. AtARP4 is a homolog of human BAF53 and yeast Arp4, and AtARP7 is a novel, ancient and plant‐specific actin‐related protein that is not distinctly related to any known ARPs from other kingdoms. Analysis of both these proteins with AtARP4‐ and AtARP7‐specific antibodies revealed that they were most abundant in young meristematic and floral tissues, but were expressed constitutively in all organs and cell types irrespective of their developmental stage. Immunofluorescence studies showed that both AtARP4 and AtARP7 were localized predominantly to the nucleus during interphase. In mitotic cells lacking a nuclear envelope (e.g. metaphase, anaphase, and early telophase stages), these ARPs were excluded from the condensed chromosomes and dispersed throughout the cytoplasm. In contrast, a putativeArabidopsishistone H2B protein remained associated with the interphase nuclei as well as chromosomes throughout the cell cycle. Based on our results and data on the yeast ortholog of AtARP4, these two nuclear plant ARPs may be involved in the modulation of chromatin structure and transcriptional regulation mainly in interphase cells.
Guidelines for irradiation of blood and blood components to prevent post‐transfusion graft‐vs.‐host disease in Japan
Authors: Asai T. , Inaba S. , Ohto H. , Osada K. , Suzuki G. , Takahashi K. , Tadokoro K. , Minami M. 
Published: March 2003

. The Japanese Red Cross analysed the results of questionnaires sent in 1993 regarding post‐transfusion graft‐vs.‐host disease (PT‐GVHD) from hospitals; the majority of patients with PT‐GVHD in 1993 were transfused for cardiovascular or cancer surgery, and about 10 patients had died yearly from PT‐GVHD in the following few years.The Japan Society of Blood Transfusion (JSBT) organized a subcommittee for the prevention of PT‐GVHD, and issued a fourth version of guidelines for the irradiation of blood to prevent PT‐GVHD. These guidelines recommended transfusion of irradiated blood for cardiosurgery, cancer surgery, elderly recipients and severe trauma, as well as congenital immunodeficient recipients, newborn infants and other immunocompromised patients. Also recommended was irradiation not only of blood within 72 h after collection but also of blood stored for 14 days. Reported PT‐GVHD has diminished to a few cases in recent years.
Platelet transfusion in the management of severe thrombocytopenia in neonatal intensive care unit patients
Authors: Murray N. A. , Howarth L. J. , McCloy M. P. , Letsky E. A. , Roberts I. A. G. 
Published: March 2003

Summary Platelet transfusions are frequently given to neonatal intensive care unit (NICU) patients with severe thrombocytopenia (platelets less than 50 × 109 L−1) but no study has assessed whether this is clinically appropriate. To address this we conducted a retrospective review of platelet transfusion practice in patients developing severe thrombocytopenia over 3 years in a single NICU. Out of 901 admissions, 53 (6%) developed severe thrombocytopenia. Twenty‐seven neonates received a total of 63 platelet transfusions, the main triggers being: platelet count less than 30 × 109 L−1 (all patients), or less than 50 × 109 L−1 in those with previous haemorrhage or clinical instability. No major haemorrhage occurred during severe thrombocytopenia either in neonates in whom platelet transfusions were withheld (26/53) or in neonates given platelets who survived to discharge (22/27). Five preterm neonates given platelets died but all had overwhelming sepsis or necrotizing enterocolitis and none died directly as a result of haemorrhage.Although the widely used liberal triggers for neonatal platelet transfusion highlighted in this review reflect available guidelines, and represent cautious (‘safe’) haemostatic practice, they are likely to result in unnecessary transfusion for a significant number of NICU patients. Improved practice requires definition of a safe lower limit for platelet count in stable neonates; effective platelet transfusion strategies for sick neonates; and improved therapies for conditions precipitating severe thrombocytopenia.
Comparison of serological and parasitological assessments of Onchocerca volvulus transmission after 7 years of mass ivermectin treatment in Mexico
Authors: Rodríguez‐Pérez Mario A. , Danis‐Lozano Rogelio , Rodríguez Mario H. , Bradley J. E. 
Published: March 2003

Summary objective and method  To compare the utility of an ELISA using 3 recombinant antigens with that of the skin biopsy to estimate incidence of infections in a sentinel cohort of individuals living in an endemic community in southern Mexico during a set of 11 subsequent ivermectin treatments. results  The apparent community prevalence of infection and microfilarial skin infection before and after 11 treatments with ivermectin plus nodulectomy were 78% and 13%, and 0.68 mf/mg and 0.04 mf/mg, respectively, as measured by skin biopsy. Of a group of 286 individuals participating in all surveys, a sentinel cohort of 42 mf and serologically negative individuals had beeen followed since 1994. The annual percentage of individuals becoming positive in this cohort was 24% (10/42), 28% (9/33), 0%, and 4.3% (1/23) in 1995, 1996, 1997 and 1998, respectively. Likewise, the incidence in children 5 years and under (n= 13) within this sentinel cohort was 15% (2/13), 18% (2/11), 0% and 11% (1/9), respectively. All individuals became positive to both tests simultaneously, indicating that seroconversion assessed infection incidence as accurately as skin biopsy in the sentinel group. conclusion  Incidence monitoring of a sentinel cohort provides an estimation of the parasite transmission in the community; it is less costly than massive sampling, and a finger prick blood test might be more acceptable in some communities.
Changing home treatment of childhood fevers by training shop keepers in rural Kenya
Authors: Marsh V. M. , Mutemi W. M. , Muturi J. , Haaland A. , Watkins W. M. , Otieno G. , Marsh K. 
Published: March 2003

Summary background Malaria control in Africa relies primarily on early effective treatment for clinical disease, but most early treatments for fever occur through self‐medication with shop‐bought drugs. Lack of information to community members on over‐the‐counter drug use has led to widespread ineffective treatment of fevers, increased risks of drug toxicity and accelerating drug resistance. We examined the feasibility and measured the likely impact of training shop keepers in rural Africa on community drug use.methods In a rural area of coastal Kenya, we implemented a shop keeper training programme in 23 shops serving a population of approximately 3500, based on formative research within the community. We evaluated the training by measuring changes in the proportions of drug sales where an adequate amount of chloroquine was purchased and in the percentage of home‐treated childhood fevers given an adequate amount of chloroquine. The programme was assessed qualitatively in the community following the shop keeper training. results The percentage of drug sales for children with fever which included an antimalarial drug rose from 34.3% (95% CI 28.9%–40.1%) before the training to a minimum of 79.3% (95% CI 71.8%–85.3%) after the training. The percentage of antimalarial drug sales where an adequate amount of drug was purchased rose from 31.8% (95% CI 26.6%–37.6%) to a minimum of 82.9% (95% CI 76.3%–87.3%). The percentage of childhood fevers where an adequate dose of chloroquine was given to the child rose from 3.7% (95% CI 1.2%–9.7%) before the training to a minimum of 65.2% (95% CI 57.7%–72.0%) afterwards, which represents an increase in the appropriate use of over‐the‐counter chloroquine by at least 62% (95% CI 53.7%–69.3%). Shop keepers and community members were strongly supportive of the aims and outcome of the programme. conclusions The large shifts in behaviour observed indicate that the approach of training shop keepers as a channel for information to the community is both feasible and likely to have a significant impact. Whilst some of the impact seen may be attributable to research effects in a relatively small scale pilot study, the magnitude of the changes support further investigation into this approach as a potentially important new strategy in malaria control.
Proposed panel of diagnostic criteria, including the use of ultrasound, to refine the concept of ‘endemic normals’ in lymphatic filariasis
Authors: Dreyer G. , Santos A. , Noroes J. , Addiss D. 
Published: March 2003

Summary Although living adult Wuchereria bancrofti worms can be detected by ultrasound examination of the scrotal area in approximately 80% of men infected with this filarial parasite, the location of the adult worms in the remaining 20% remains unclear. To determine this, 32 individuals who had W. bancrofti microfilaraemia but no adult worms detectable on ultrasound were treated with diethylcarbarmazine (DEC), either with a single 6 mg/kg dose (n = 13) or with a 12‐day course of 6 mg/kg per day (n = 19). They were then monitored with serial physical and ultrasound examinations. Thirteen (41%) subjects developed small, single scrotal nodules 12 h to 7 days after treatment; this rate was unaffected by the dose of DEC. No nodules were detected outside the scrotal area. All 5 men with lymphangiectasia suspected on ultrasound before treatment developed scrotal nodules, compared to 8 (29.6%) of 27 men without ultrasonographic evidence (P = 0.006). Thus, using both ultrasound and ‘provocative’ treatment with DEC, adult W. bancrofti can be detected in the scrotal area of an estimated 88% of infected men. Because no single diagnostic test for W. bancrofti infection is completely sensitive, a panel of tests, including ultrasound, is proposed to identify with greater accuracy ‘endemic normals’ for immunological and epidemiological studies.
Prevalence of antibodies against hepatitis A and E viruses among rural populations of the Chaco region, south‐eastern Bolivia
Authors: Bartoloni Alessandro , Bartalesi Filippo , Roselli Mimmo , Mantella Antonella , Caceres Arce Cleto , Paradisi Franco , Hall Andrew J. 
Published: March 2003

Summary We conducted a cross‐sectional study to determine the seroprevalence of antibodies against hepatitis A and hepatitis E viruses (HAV and HEV) in the population of two rural areas, Camiri and Villa Montes, of the Chaco region, south‐eastern Bolivia. HAV antibodies were detected in 461 (94.1%) of 490 serum samples tested, not differing significantly between sexes and study areas. The HAV seropositivity rate (64.7%) was high even in the youngest age group (1–5 years). The prevalence of HEV was 7.3%, with no significant differences between sexes. The prevalence of HEV antibodies in the population of the Camiri area (10.4%) was significantly higher than in the Villa Montes area (4.4.%), possibly due to the better quality of drinking water in the Villa Montes area. In the population ≤ 30 years of age, the HEV seropositivity rate (4.4%) was significantly lower than in the ≥ 31 year‐old group. This is consistent with findings in other countries. This is the first report of the prevalence of HEV infection in Bolivia.
Spatial implications of the tuberculosis DOTS strategy in rural South Africa: a novel application of geographical information system and global positioning system technologies
Authors: Tanser Frank , Wilkinson David 
Published: March 2003

Summary We used GIS/GPS technology to document and quantify improved access to tuberculosis treatment through a community‐based programme in Hlabisa, South Africa. We plotted tuberculosis supervision points used by the district health system in 1991 (programme's first year) and 1996 (programme fully established), and quantified access by using GIS to measure the mean distance from each homestead in the district to hospital, clinics, community health workers (CHW) and volunteer supervisors. While the tuberculosis caseload tripled, the number of community supervision points used increased from 37 in 1991 to 147 in 1996. Adding clinics and then CHWs to the hospital as treatment points reduced the mean distance from homestead to treatment point from 29.6 km to 4.2 km and to 1.9 km, respectively. Adding volunteers further decreased the distance to 800 m. GIS/GPS effectively documents and quantifies the impact of community‐based tuberculosis treatment on access to treatment.
Assessment of IgG antibodies against yellow fever virus after vaccination with 17D by different assays: neutralization test, haemagglutination inhibition test, immunofluorescence assay and ELISA
Authors: Niedrig M. , Lademann M. , Emmerich P. , Lafrenz M. 
Published: March 2003

Summary We analysed serum samples of 209 subjects immunized with yellow fever vaccine 17D by different assays: neutralization test, immunofluorescence assay, haemagglutination inhibition test and ELISA, for presence of 17D‐specific antibodies. Serum samples were taken from a few weeks up to 35 years after vaccination. The neutralization test had the highest sensitivity. There was no correlation of results between the serological assays. Considering NT titres > 1:10 as indicating protection, we found that about 75% of subjects remained immune even 10 years after vaccination, with a median NT titre of 1:40 in reactive sera.
Reliability of malaria microscopy in epidemiological studies: results of quality control
Authors: Kilian A. H. D. , Metzger W. G. , Mutschelknauss E. J. , Kabagambe G. , Langi P. , Korte R. , von Sonnenburg F. 
Published: March 2003

Summary To assess the interrater reproducibility of malaria microscopy in epidemiological studies, 711 thick blood films from population‐based surveys were randomly selected and reread by 4 experienced microscopists. Sample estimates of the prevalence of P. falciparum infection, geometric mean parasite density and the proportion of samples above various parasite density cut‐off levels were almost identical in the routine and quality control readings. Differences were, however, encountered in the sample estimates for gametocyte ratio, proportion of mixed infection and average density index. In all three cases the quality control result was significantly higher than the routine evaluation. On the level of the individual slide there was good interrater agreement for the presence of P. falciparum infections (Kappa index κ = 0.79) which was even better when parasite densities between 4 and 100/μl were excluded (κ = 0.94). With respect to the assessment of parasite density, a high level of disagreement was found. While the mean difference between the two readings was not different from 0, the second reading was between 0.12 and 10 times that of the first. However, the level of disagreement significantly fell with increasing parasite densities. Thus malaria microscopy is very reliable for the estimation of parasite ratios and geometric mean parasite densities within and between studies as long as the same methodology is used, but tends to underestimate the gametocyte ratio and proportion of mixed infections. Care must be taken, however, when individual parasite density is related to other explanatory variables, due to the high degree of variability in the parasite enumeration.
International multi‐centre evaluation of a dipstick assay for human leptospirosis
Authors: Smits Henk L. , Hartskeerl Rudy A. , Terpstra Wiepko J. 
Published: March 2003

Summary A dipstick assay for the detection of Leptospira‐specific immunoglobulin M (IgM) antibodies in human sera was evaluated in 27 laboratories in 23 countries. 873 serum samples from 711 patients including 329 laboratory‐confirmed leptospirosis case patients, 239 noncase patients and 69 patients with viral infections causing heamorrhagic fever were tested. Relative to the results of the reference leptospirosis test, the sensitivity of the dipstick assay was 84.5% for serum samples collected during the first 10 days of the disease and 92.1% for serum samples collected 10–30 days after the onset of disease. The specificity was 87.5% and 94.4%, respectively. Similar to viral haemorrhagic fevers, leptospirosis may cause bleeding. A small number of serum samples from patients with haemorrhagic viral infections gave a weak (1 +) stain. All other samples were negative. In conclusion, the dipstick assay is sensitive and specific and reacts well with serum samples from patients infected with a range of leptospiral strains. It is also easy to use and does not require special equipment or refrigeration. Therefore the assay is ideal for use in developing countries and rural settings.
Sociodemographic characteristics, care, feeding practices, and growth of cohorts of children born to HIV‐1 seropositive and seronegative mothers in Nairobi, Kenya
Authors: Sherry Bettylou , Embree Joanne E. , Mei Zuguo , Ndinya‐Achola Jackoniah O. , Njenga Simon , Muchunga Elisha R. , Bett Josephine , Plummer Francis A. 
Published: March 2003

Summary objectives To compare sociodemographic profiles, child care, child feeding practices and growth indices of children born to HIV‐1 seropositive and seronegative mothers. methods A cohort study of 234 children (seropositive and seronegative) born to HIV‐1 seropositive mothers and 139 children born to seronegative mothers in Pumwani Maternity Hospital which serves a low‐income population in Nairobi, Kenya from December 1991 and January 1994. results With few exceptions, at the time of their birth children in all three cohorts had parents with similar characteristics, lived in similar housing in similar geographical areas, had their mothers as their primary care givers, had similar feeding practices and similar growth status and patterns. However, the HIV‐1 seropositive mothers were slightly younger (23.8 years vs. 25.0 years, P < 0.01), if married they were less likely to be their husband's first wife (79% vs. 91%, P = 0.02) and more likely to have a one‐room house (75% vs. 63%, P = 0.04). All three cohorts had mean Z‐scores in length‐for‐age and in weight‐for‐height within the normal range (≥ 2.0 Z‐scores) from birth to 21 months with the exception of the length‐for‐age of the seropositive children at the 18‐month visit. In all cohorts length‐for‐age became more compromised than weight‐for‐length, dropping to about −1.45 Z‐score by 21 months; in contrast, weight‐for‐length dropped to about −0.5 Z‐score by this age. The only statistically significant differences in growth indices among the three cohorts were between the two cohorts of seronegative children: those with seronegative mothers were less compromised in length‐for‐age at 1.5 months (mean Z‐score =−0.19 vs.−0.48, P < 0.05) and more compromised in weight‐for‐length at 6 months (mean Z‐score = 0.10 vs. 0.45, P < 0.05) and at 18 months (mean Z‐score =−0.73 vs.−0.16, P < 0.05). 27–34% were exclusively breastfed at 1.5 months; 52–61% consumed solid foods in addition to breast milk by 2.5 months. conclusions Low‐income HIV‐1 seropositive‐ and seronegative‐born children were from families with similar characteristics and similar housing environments. Similar growth patterns in the cohorts suggest that the challenging environment and the choice of weaning foods had an impact on all three cohorts. The aggressive care given the children with HIV‐1 seropositive mothers and their children may have reduced the progression and impact of HIV‐1 disease on the growth of the seropositive children. Further research is needed to corroborate our findings to be certain that our results are not affected by loss to follow‐up bias: we lost the same proportion in all three cohorts but cannot verify that the children we lost had the same growth patterns as those who remained in the study.