bluuebunny/crossref_metadata_2025_split huggingface dataset:
A single aromatic residue in transcriptional repressor protein KorA is critical for cooperativity with its co‐regulator KorB
Authors: Bingle Lewis E. H. , Rajasekar Karthik V. , Muntaha Sidra tul , Nadella Vinod , Hyde Eva I. , Thomas Christopher M. 
Published: November 2008

SummaryA central feature of broad host range IncP‐1 plasmids is the set of regulatory circuits that tightly control plasmid core functions under steady‐state conditions. Cooperativity between KorB and either KorA or TrbA repressor proteins is a key element of these circuits and deletion analysis has implicated the conserved C‐terminal domain of KorA and TrbA in this interaction. By NMR we show that KorA and KorB interact directly and identify KorA amino acids that are affected on KorB binding. Studies on mutants showed that tyrosine 84 (or phenylalanine, in some alleles) is dispensable for repressor activity but critical for the specific interaction with KorB in both in vivo reporter gene assays and in vitro electrophoretic mobility shift and co‐purification assays. This confirms that direct and specific protein–protein interactions are responsible for the cooperativity observed between KorB and its corepressors and lays the basis for determining the biological importance of this cooperativity.
The replication fork trap and termination of chromosome replication
Authors: Duggin Iain G. , Wake R. Gerry , Bell Stephen D. , Hill Thomas M. 
Published: November 2008

SummaryBacteria that have a circular chromosome with a bidirectional DNA replication origin are thought to utilize a ‘replication fork trap’ to control termination of replication. The fork trap is an arrangement of replication pause sites that ensures that the two replication forks fuse within the terminus region of the chromosome, approximately opposite the origin on the circular map. However, the biological significance of the replication fork trap has been mysterious, as its inactivation has no obvious consequence. Here we review the research that led to the replication fork trap theory, and we aim to integrate several recent findings that contribute towards an understanding of the physiological roles of the replication fork trap. Likely roles include the prevention of over‐replication, and the optimization of post‐replicative mechanisms of chromosome segregation, such as that involving FtsK in Escherichia coli.
A novel component of the division‐site selection system of Bacillus subtilis and a new mode of action for the division inhibitor MinCD
Authors: Bramkamp Marc , Emmins Robyn , Weston Louise , Donovan Catriona , Daniel Richard A. , Errington Jeff 
Published: November 2008

SummaryCell division in bacteria is governed by a complex cytokinetic machinery in which the key player is a tubulin homologue, FtsZ. Most rod‐shaped bacteria divide precisely at mid‐cell between segregated sister chromosomes. Selection of the correct site for cell division is thought to be determined by two negative regulatory systems: the nucleoid occlusion system, which prevents division in the vicinity of the chromosomes, and the Min system, which prevents inappropriate division at the cell poles. In Bacillus subtilis recruitment of the division inhibitor MinCD to cell poles depends on DivIVA, and these proteins were thought to be sufficient for Min function. We have now identified a novel component of the division‐site selection system, MinJ, which bridges DivIVA and MinD. minJ mutants are impaired in division because MinCD activity is no longer restricted to cell poles. Although MinCD was thought to act specifically on FtsZ assembly, analysis of minJ and divIVA mutants showed that their block in division occurs downstream of FtsZ. The results support a model in which the main function of the Min system lies in allowing only a single round of division per cell cycle, and that MinCD acts at multiple levels to prevent inappropriate division.
Mhp493 (P216) is a proteolytically processed, cilium and heparin binding protein ofMycoplasma hyopneumoniae
Authors: Wilton Jody , Jenkins Cheryl , Cordwell Stuart J. , Falconer Linda , Minion F. Chris , Oneal David C. , Djordjevic Michael A. , Connolly Angela , Barchia Idris , Walker Mark J. , Djordjevic Steven P. 
Published: November 2008

SummaryMycoplasma hyopneumoniaeinduces respiratory disease in swine by colonizing cilia causing ciliostasis, cilial loss and epithelial cell death. Heparin binds toM. hyopneumoniaecells in a dose‐dependent manner and blocks its ability to adhere to porcine cilia. We show here that Mhp493 (P216), a paralogue of the cilium adhesin P97 (Mhp183), is cleaved between amino acids 1040 and 1089 generating surface‐accessible, heparin‐binding proteins P120 and P85. Antiphosphoserine antibodies recognized P85 in 2‐D immunoblotting studies and TiO2chromatography of trypsin digests of P85 isolated a single peptide with an m/z of 917.3. A phosphoserine residue in the tryptic peptide90VSELpSFR96(position 94 in P85) was identified by MALDI‐MS/MS. Polyhistidine fusion proteins (F1P216, F2P216, F3P216) spanning Mhp493 bound heparin with biologically significant Kd values, and heparin, fucoidan and mucin inhibited this interaction. Latex beads coated with F1P216, F2P216and F3P216adhered to and entered porcine kidney epithelial‐like (PK15) cell monolayers. Microtitre plate‐based assays showed that sequences within P120 and P85 bind to porcine cilia and are recognized by serum antibodies elicited during infection byM. hyopneumoniae. Mhp493 contributes significantly to the surface architecture ofM. hyopneumoniaeand is the first cilium adhesin to be described that lacks an R1 cilium‐binding domain.
Mycobacterium tuberculosis expresses methionine sulphoxide reductases A and B that protect from killing by nitrite and hypochlorite
Authors: Lee Warren L. , Gold Benjamin , Darby Crystal , Brot Nathan , Jiang Xiuju , De Carvalho Luiz Pedro S. , Wellner Daniel , St. John Gregory , Jacobs Jr William R. , Nathan Carl 
Published: November 2008

SummaryMethionine sulphoxide reductases (Msr) reduce methionine sulphoxide to methionine and protect bacteria against reactive oxygen intermediates (ROI) and reactive nitrogen intermediates (RNI). Many organisms express both MsrA, active against methionine‐(S)‐sulphoxide, and MsrB, active against methionine‐(R)‐sulphoxide. Mycobacterium tuberculosis (Mtb) expresses MsrA, which protects ΔmsrA‐Escherichia coli from ROI and RNI. However, the function of MsrA in Mtb has not been defined, and it is unknown whether Mtb expresses MsrB. We identified MsrB as the protein encoded by Rv2674 in Mtb and confirmed the distinct stereospecificities of recombinant Mtb MsrA and MsrB. We generated strains of Mtb deficient in MsrA, MsrB or both and complemented the mutants. Lysates of singly deficient strains displayed half as much Msr activity as wild type against N‐acetyl methionine sulphoxide. However, in contrast to other bacteria, single mutants were no more vulnerable than wild type to killing by ROI/RNI. Only Mtb lacking both MsrA and MsrB was more readily killed by nitrite or hypochlorite. Thus, MsrA and MsrB contribute to the enzymatic defences of Mtb against ROI and RNI.
sodA is essential for virulence of Borrelia burgdorferi in the murine model of Lyme disease
Authors: Esteve‐Gassent Maria D. , Elliott Nathaniel L. , Seshu J. 
Published: November 2008

Summary Borrelia burgdorferi, the causative agent of Lyme disease, has a limited set of genes to combat oxidative/nitrosative stress encountered in its tick vector or mammalian hosts. We inactivated the gene encoding for superoxide dismutase A (sodA, bb0153), an enzyme mediating the dismutation of superoxide anions and examined the in vitro and in vivo phenotype of the mutant. There were no significant differences in the in vitro growth characteristics of the sodA mutant compared with the control strains. Microscopic analysis of viability of spirochaetes revealed greater percentage of cell death upon treatment of sodA mutant with superoxide generators compared with its controls. Infectivity analysis in C3H/HeN mice following intradermal needle inoculation of 103 or 105 spirochaetes per mouse revealed complete attenuation of infectivity for the sodA mutant compared with control strains at 21 days post infection. The sodA mutant was more susceptible to the effects of activated macrophages and neutrophils, suggesting that its in vivo phenotype is partly due to the killing effects of activated immune cells. These studies indicate that SodA plays an important role in combating oxidative stress and is essential for the colonization and dissemination of B. burgdorferi in the murine model of Lyme disease.
The thioredoxin reductase‐glutaredoxins‐ferredoxin crossroad pathway for selenate tolerance in Synechocystis PCC6803
Authors: Marteyn Benoit , Domain Francis , Legrain Pierre , Chauvat Franck , Cassier‐Chauvat Corinne 
Published: November 2008

SummaryMost organisms use two systems to maintain the redox homeostasis of cellular thiols. In the thioredoxin (Trx) system, NADPH sequentially reduces thioredoxin reductases (NTR), Trxs and protein disulfides. In the glutaredoxin (Grx) system, NADPH reduces the glutathione reductase enzyme occurring in most organisms, glutathione, Grxs, and protein disulfides or glutathione‐protein mixed disulfides. As little is known concerning these enzymes in cyanobacteria, we have undertaken their analysis in the model strain Synechocystis PCC6803. We found that Grx1 and Grx2 are active, and that Grx2 but not Grx1 is crucial to tolerance to hydrogen peroxide and selenate. We also found that Synechocystis has no genuine glutathione reductase and uses NTR as a Grx electron donor, in a novel integrative pathway NADPH‐NTR‐Grx1‐Grx2‐Fed7 (ferredoxin 7), which operates in protection against selenate, the predominant form of selenium in the environment. This is the first report on the occurrence of a physical interaction between a Grx and a Fed, and of an electron transfer between two Grxs. These findings are discussed in terms of the (i) selectivity of Grxs and Feds (Synechocystis possesses nine Feds), (ii) crucial importance of NTR for cell fitness and (iii) resistance to selenate, in absence of a Thauera selenatis‐like selenate reductase.
Female genital schistosomiasis – a differential diagnosis to sexually transmitted disease: genital itch and vaginal discharge as indicators of genital Schistosoma haematobium morbidity in a cross‐sectional study in endemic rural Zimbabwe
Authors: Kjetland Eyrun Floerecke , Kurewa Edith Nyaradzai , Ndhlovu Patricia D. , Midzi Nicholas , Gwanzura Lovemore , Mason Peter R. , Gomo Exnevia , Sandvik Leiv , Mduluza Takafira , Friis Henrik , Gundersen Svein Gunnar 
Published: November 2008

SummaryObjective  To examine the association between schistosomiasis and reproductive tract symptoms.Method  A cross‐sectional study was conducted in a Schistosoma haematobium‐endemic area of rural Zimbabwe. A total of 483 permanently resident adult women of Mupfure Ward aged 20–49 were interviewed and examined clinically, each providing three consecutive urine samples. Logistic regression analysis was used to control for sexually transmitted diseases (STDs).Results  Women with genital sandy patches had significantly more genital itch (P = 0.009) and perceived their discharge as abnormal (P = 0.003). Eighty percent of the women who had genital itch, yellow discharge, and childhood or current waterbody contact had sandy patches. Fifty‐two percent of the women with genital sandy patches did not have detectable S. haematobium ova in urine. Genital schistosomiasis was associated with stress incontinence and pollakisuria, but not with menstrual irregularities, current or previous ulcers, or tumours.Conclusion  Genital schistosomiasis may be a differential diagnosis to the STDs in women who have been exposed to fresh water in endemic areas. Because of the chronic nature of the disease in adults, we suggest to pay special attention to the prevention of morbidity.
Inconclusive results in conventional serological screening for Chagas’ disease in blood banks: evaluation of cellular and humoral response
Authors: Furuchó Celia Regina , Umezawa Eufrozina S. , Almeida Igor , Freitas Vera L. , Bezerra Rita , Nunes Elisabete V. , Sanches Maria C. , Guastini Cristina M. , Teixeira Antonio R. , Shikanai‐Yasuda Maria A. 
Published: November 2008

SummaryObjective  To find the most reliable screening method for Trypanosoma cruzi infection in blood banks.Material and methods  Epidemiological data, lymphoproliferation assay, parasitological, conventional serological tests: immunofluorescence, haemagglutination, ELISA with epimastigote and trypomastigote antigens and reference serological tests: trypomastigote excreted‐secreted antigens (TESA) blot and chemiluminescent ELISA assay with mucine from trypomastigote forms were applied to individuals with inconclusive serology, non‐chagasic individuals and chronic chagasic patients.Results  TESA blot had the best performance when used as a single test in all the groups. In the inconclusive group 20.5% of individuals were positive for TESA blot, 23.3% for either lymphoproliferation or TESA blot, and 17.8% for lymphoproliferation only. Positive lymphoproliferation without detectable antibodies was observed in 5.47% of all inconclusive serology cases. Analysis of six parameters (three serological assays, at least one parasitological test, one lymphoproliferation assay and epidemiological data) in the inconclusive group showed that diagnosis of Chagas’ disease was probable in 15 patients who were positive by two or more serological tests or for whom three of those six parameters were positive.Conclusion  TESA blot is a good confirmatory test for Chagas’ disease in the inconclusive group. Although lymphoproliferation suggests the diagnosis of Chagas’ disease in the absence of antibodies when associated with a high epidemiological risk of acquiring Chagas’ disease, the data from this study and the characteristics of the lymphoproliferation assay (which is both laborious and time‐consuming) do not support its use as a confirmatory test in blood‐bank screening. However, our findings underscore the need to develop alternative methods that are not based on antibody detection to improve the diagnosis when serological tests are inconclusive.
Making a working clinical diagnosis of HIV infection in infants in Zimbabwe
Authors: Iliff Peter , Ntozini Robert , Nathoo Kusum , Piwoz Ellen , Moulton Lawrence ,   The ZVITAMBO Study Group, Humphrey Jean 
Published: November 2008

SummaryObjectives  Clinical algorithms can be helpful in decisions about treatment and feeding options in infancy, but have had limited exposure to real data. This analysis uses data from a large clinical trial to test such algorithms, and thereby develop a successor which performs usefully in poor countries with high HIV‐prevalence.Methods  The ZVITAMBO trial followed 14 110 mother‐baby pairs through infancy. 32% of mothers were HIV‐positive. Infants were HIV tested regularly using DNA PCR. Clinical signs were evaluated in terms of identifying HIV‐infection at 6 weeks, 6 and 12 months, using Zimbabwean, South African, and WHO generic adaptations of the WHO integrated management of childhood illness HIV algorithm. A modification, in which HIV‐exposed infants are first divided into being at least or less than median weight‐for‐age, was derived and evaluated.Results  At 6 weeks 65% of all infected babies are less than median weight‐for‐age. Adding at least two clinical signs reduces sensitivity to 20% but those identified are 1.5 (95% CI 1.1–2.1) times more likely to die by 6 months than other infected infants. At 6 months, 86% of uninfected babies of HIV‐infected mothers can be identified by selecting those whose weight is greater than median or, if less than median, who exhibit <2 clinical signs.Conclusions  In poor settings a simple clinical algorithm can identify children with probable HIV infection, especially those at risk of early death, who can then be referred for further testing and care, including highly active antiretroviral therapy. Most infants who are HIV‐uninfected can be identified at 6 months and provided with support to maintain infection‐free survival, including focussed infant‐feeding counselling.
Comparative analysis of anoxic coleoptile elongation in rice varieties: relationship between coleoptile length and carbohydrate levels, fermentative metabolism and anaerobic gene expression
Authors: Magneschi L. , Kudahettige R. L. , Alpi A. , Perata P. 
Published: November 2008

AbstractRice (Oryza sativa L.) seeds can germinate under anoxia and can show coleoptile elongation. The anoxic coleoptile is usually longer than aerobic coleoptiles. Although several hypotheses have been proposed to explain the ability of rice to elongate coleoptiles under anoxia, conclusive experimental evidence explaining this physiological trait is lacking. In order to investigate whether metabolic and molecular markers correlate with anoxic coleoptile length, we screened 141 Italian and 23 Sri Lankan rice cultivars for their ability to elongate coleoptiles under anoxia. Differences in anoxic coleoptile length were used to evaluate whether a correlation exists between coleoptile length and biochemical and molecular parameters. The expression of genes coding for glycolytic and fermentative enzymes showed a very low correlation with anoxic coleoptile length. Although differences were found in carbohydrate content between the varieties tested, this parameter also does not appear to be critical in terms of coleoptile elongation. Efficient ethanol fermentation does, however, correlate well with the elongation of coleoptiles under anoxic conditions.
Infection of Blackcurrant Leaves by Drepanopeziza ribis in Relation to Weather Conditions and Leaf Position
Authors: Xu Xiang Ming , Robinson Joyce D. , Berrie Angela M. 
Published: November 2008

Abstract Drepanopeziza ribis causes the leaf spot disease of blackcurrant (Ribes nigrum) and may lead to severe premature leaf‐fall. Artificial inoculation studies were carried out to investigate infection of leaves by D. ribis conidia in relation to environmental conditions and leaf position (age) on cvs. Baldwin and Ben Hope in April and July 2007. All leaves on a number of selected extension shoots on potted three‐year old plants were inoculated with conidia and then incubated under different conditions: 10, 17.5 and 25°C each with five wet periods (4, 8, 12, 24 and 30 h). Number of infected leaves was determined. The two cultivars differed significantly in their susceptibility to conidial infection: cv. Baldwin was much more susceptible than cv. Ben Hope. Older leaves on extension shoots were more susceptible to conidial infection than younger leaves. Increasing length of wetness duration led to increasing incidence of leaves infected, particularly when inoculated in July. However, the effects of temperature were inconclusive and generally very small in comparison with other factors. Field epidemics were monitored over three years (2005–07). Field data confirmed the main findings from controlled inoculation studies: severe disease was associated with very wet conditions and older leaves. Furthermore, they also suggested that significant disease increase only occurred from late July onwards.
Sorghum protein digestibility is affected by dosage of mutant alleles in endosperm cells
Authors: Tesso T. , Hamaker B. R. , Ejeta G. 
Published: November 2008

AbstractProtein digestibility in grain sorghum (Sorghum bicolor (L.) Moench) is affected by the structure of endosperm protein bodies that limits access of digestive enzymes to storage protein. In this experiment, we studied the effect of endosperm dosage of high digestible alleles (hd+) on protein digestibility in sorghum hybrids carefully constituted for such a study. We also examined the effect that these alleles may have on endosperm protein body structure and agronomic performance of the hybrids. The results showed that protein digestibility, endosperm texture and protein body morphology were highly influenced by dosage of mutant alleles. Genotypes carrying two or more hd+ alleles had significantly higher protein digestibility than those with one or no mutant allele. Similarly, higher doses of these alleles resulted in opaque endosperm phenotype while the wild type alleles produced normal vitreous texture. Moreover, hybrids carrying variable proportions of mutant alleles had uniquely irregular but variable protein body structure that was distinct from spherical protein bodies found in normal genotypes. Agronomic performance was not affected by dosage of digestibility alleles.
Characterization of gene expression profiles in developing kernels of maize (Zea mays) inbred Tex6
Authors: Luo M. , Liu J. , Lee R. D. , Guo B. Z. 
Published: November 2008

AbstractMaize inbred Tex6 is resistant to several pests. The objectives of this study were to characterize gene expression profiles in Tex6 kernels and identify unique genes that expressed up‐ or down‐ward in developing kernels in the later stages. Because of the resistance of Tex6 kernels, we reasoned that it would be an interesting candidate for microarray study. By using maize microarray, we analysed gene expression profiles in developing kernels from 25 DAP (days after pollination) to 45 DAP. A total of 8497 positive array spots were detected with unique IDs, in which 4247 genes were detected in all samples. The trends of total expressed genes were decreasing when kernels were maturing. Expression patterns of some genes in several metabolic pathways, including starch, lipid and storage proteins, were analysed. In comparison with 25 DAP, expressions of 211 gene features were significantly different at 45 DAP (P < 0.05), which will be used to produce a macroarray for germplasm assessment and evaluation. The real‐time qRT‐PCR was used to validate microarray study.
Prevalence, correlates, and disease patterns of antipsychotic use in Taiwan
Authors: Chien I‐Chia , Hsu Jer‐Hwa , Bih Shin‐Huey , Lin Ching‐Heng , Chou Yiing‐Jenq , Lee Cheng‐Hua , Chou Pesus 
Published: November 2008

Aim:  The population‐based National Health Insurance database was used to investigate the prevalence, correlates, and disease patterns of antipsychotic use in Taiwan.Methods:  The National Health Research Institutes provided a database of 200 000 random subjects for study. A random sample of 145 304 subjects was obtained, aged ≥18 years in 2004. Study subjects who had been given at least two antipsychotic drug prescriptions during this year were identified. The factors associated with any antipsychotic use were identified. The proportion of antipsychotic use for psychiatric and non‐psychiatric disorders was also examined.Results:  The 1‐year prevalence of antipsychotic use was 3.5%. Antipsychotic use was found to be more prevalent by age; for women; for individuals with a lower insurance amount; for individuals with disability; and among those subjects who lived in the central or southern area. Among subjects with antipsychotic use, higher proportions of psychiatric disorders were found for schizophrenia, anxiety state, major depressive disorder, neurotic depression, dementia, and bipolar disorder. With respect to medical disorder, higher proportions of antipsychotic use were found for diseases of the digestive system; symptoms, signs, and ill‐defined conditions; diseases of the respiratory system, musculoskeletal system and connective tissue, circulatory system, nervous system and sense organs, and genitourinary system.Conclusions:  Higher proportions of antipsychotic use were found for schizophrenia, depressive disorder, anxiety disorder, dementia, and bipolar disorder. More than 60% of subjects used antipsychotics for non‐psychiatric disorders in Taiwan, which deserves further study for the sake of patient safety.