bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in condylar path inclination during maximum protrusion between the ages of 6 and 12 years
Authors: BAQAIEN M. A. , AL‐SALTI F. M. , MUESSIG D.
Published: December 2006

summary  The purpose of this study is to quantify the changes in sagittal condylar path inclination during mandibular protrusion between the ages of 6 and 12 years. A total of 172 children (82 males and 90 females) ranging in age from 6·5 to 12·9 years were divided according to their chronological age into five subgroups with mean ages of 7·1, 8, 9, 10 and 11·4 years respectively. The control group consisted of 41 adults with a mean age of 28 years. All subjects had a normal temporomandibular joint function and neutral occlusion. Five maximum protrusion–retrusion movements were recorded with six degrees of freedom in each subject using an ultrasound (JMA®) jaw‐tracking system. Initially, condylar path inclination angle (CPIA) was calculated stepwise for each millimetre distance, for the first 10 mm of protrusive tracing path on both sides. A single mean value was then assigned for the entire protrusive path. One‐way analysis of variance proved to be significant among the five subgroups of children. Linear regression analysis showed that condylar path had a tendency to become steeper with age, although it was statistically weak. The data indicated that the mean CPIA is 43°–44° at the age of seven, increases annually by 1·2°–1·3° and reaches an average of 49°–50° by the age of 12 at which time it attains around 83–85% of its adult level. In subgroup V, the female population had significantly steeper condylar path on the left‐hand side than the male population. Condylar path inclinations indicated a symmetrical growth pattern of the articular eminence.
Changes in jaw muscle EMG activity and pain after third molar surgery
Authors: ERNBERG M. , SCHOPKA J. H. , FOUGERONT N. , SVENSSON P.
Published: December 2006

summary  Limited jaw‐opening capacity is frequently encountered following third molar surgery and may impair function. The aim of this study was to investigate the electromyographic (EMG) activity in jaw muscles after third molar surgery to obtain more insight into the mechanisms of restrictions in jaw opening. Twenty subjects were examined before, 24 h and 1 week after surgery. Ten healthy controls were subjected to the same examination at two different occasions for intersession variability. The EMG activity of the masseter and anterior digastricus muscles was recorded at different jaw positions and during maximum voluntary clenching. Pain intensity was assessed at rest and during movements. The EMG activity in the jaw muscles increased with opening level (P < 0·01), but did not change after surgery. In contrast, the EMG activity during clenching was decreased in all muscles after surgery (P < 0·05). The pain intensity after surgery increased with jaw opening level (P < 0·001), but was in general not correlated to EMG level. Pain intensity during clenching was increased after surgery (P < 0·001), but not correlated to EMG level. The EMG activity did not change between visits in the control group. In conclusion, the results indicate that third molar surgery does not influence the EMG activity in the masseter and anterior digastricus muscles during various levels of static jaw opening, but decreases the EMG activity during clenching. However, these changes are not influenced by pain intensity. The results have implications for the understanding of the phenomenon of trismus.
Cervical spine alignment and hyoid bone positioning with temporomandibular disorders
Authors: ANDRADE A. V. , GOMES P. F. , TEIXEIRA‐SALMELA L. F.
Published: December 2006

summary  The relationships between temporomandibular joint (TMJ) disorders and cervical structure dysfunctions have already been demonstrated. The aim of the present study was to investigate functional and structural alterations of the head and neck of 17 individuals with TMJ disorders (TMD group), compared with a control group of 17 asymptomatic subjects in a cross‐sectional design. The outcome variables included pain on palpation of the sternocleidomastoideus, superior trapezius and subocciptal muscles, as well as radiographic measures of alignment of the cervical spine and positioning of the hyoid bone. Cervical alignment, determined by measures of the cervical curvature angle, was investigated by the Cobb method. Independent Student t‐tests were used to investigate differences between groups for all outcome variables (α < 0·05). The results demonstrated that individuals with TMJ disorders, when compared with asymptomatic subjects, presented higher levels of perception of pain in all cervical muscles (P < 0·0001). No significant differences were found between groups for the cervical alignment measures. In the TMD group, the position of the hyoid bone in relation to the cervical spine did not appear to be different from the control group.
Risk factors for hepatitis C fibrosis: a prospective study of United States veterans* compared with nonveterans
Authors: Kayali Z. , Tan S. , Shinkunas L. , Voigt M. , LaBrecque D. R. , Stapleton J. T. , Brown K. E. , Schmidt W. N.
Published: December 2006

Summary.  Chronic hepatitis C virus (HCV) infection causes cirrhosis in many infected patients; however, a better understanding of the risk factors for fibrosis progression in high HCV prevalence groups such as US veterans is needed. We wished to compare the demographic, clinical characteristics, and independent variables that influence fibrosis in US veterans vs nonveterans with chronic HCV. HCV‐seropositive US veterans (n = 459) and nonveterans (n = 395) prospectively completed a detailed medical, social and occupational questionnaire. Clinical factors for progressive liver disease were compared between veterans and nonveterans and fibrosis stage assessed on liver biopsies (168 veterans and 208 nonveterans). Using polychotomous logistic regression, fibrosis was analysed as both a progressive and categorical outcome to determine independent risk factors for both patient groups. Although veterans were significantly older and had higher lifetime alcohol consumption than nonveterans, their median fibrosis scores did not differ from nonveterans. By univariate analysis, alanine aminotransferase, necroinflammatory activity (NIA), and cryoglobulin positivity were associated with fibrosis in veterans and nonveterans (P < 0.05, all comparisons), whereas steatosis was associated with fibrosis only in nonveterans (P < 0.0001). By multivariate analysis, NIA was an independent risk factor for fibrosis in both groups (P < 0.01). However, fibrosis in nonveterans was also independently associated with steatosis, significant alcohol consumption and age (P < 0.04, all comparisons). Independent risk factors for fibrosis vary among high HCV prevalence groups such as veterans when compared with nonveterans. Understanding specific patient cohort effects is important for determining independent risk factors for disease progression in chronic HCV infection.
Long‐term surveillance of haematopoietic stem cell recipients with resolved hepatitis B: high risk of viral reactivation even in a recipient with a vaccinated donor
Authors: Knöll A. , Boehm S. , Hahn J. , Holler E. , Jilg W.
Published: December 2006

Summary.  Reactivation of resolved hepatitis B virus (HBV) infection is increasingly recognized in patients with severe immunosuppression. We monitored seven patients with pretransplant antibodies to hepatitis B surface antigen (anti‐HBs) and hepatitis B core antigen (anti‐HBc) for HBV reactivation after allogeneic haematopoietic stem cell transplantation (allo‐HSCT). Reverse seroconversion (from anti‐HBs to HBsAg) was observed in six recipients occurring 12, 14, 16, 22, 31 and 39 months after allo‐HSCT, respectively. The only patient without HBV reactivation had the highest pretransplant anti‐HBs titre and died after the shortest follow‐up period (25 months). A novel HBV surface mutant (D144G/G145E) was isolated from one recipient of stem cells from a donor vaccinated against HBV. Another surface mutant (P142L/G145R) was detected in a recipient from a non‐immune donor. Serum ALT elevation was measured in only two of the six patients with viral reactivation, followed by spontaneous clearance of HBsAg in one of them. Antiviral treatment reduced viral load in five patients, but the emergence of YMDD motif polymerase mutations resulted in lamivudine resistance in two patients. In conclusion, the risk of reactivation of a resolved HBV infection is close to 100% in allogeneic stem cell recipients and vaccination of the donor does not always warrant reliable protection.
Detecting female precise natal philopatry in green turtles using assignment methods
Authors: LEE PATRICIA L. M. , LUSCHI PAOLO , HAYS GRAEME C.
Published: December 2006

It is well established that sea turtles return to natal rookeries to mate and lay their eggs, and that individual females are faithful to particular nesting sites within the rookery. Less certain is whether females are precisely returning to their natal beach. Attempts to demonstrate such precise natal philopatry with genetic data have had mixed success. Here we focused on the green turtles of three nesting sites in the Ascension Island rookery, separated by 5–15 km. Our approach differed from previous work in two key areas. First, we used male microsatellite data (five loci) reconstructed from samples collected from their offspring (N = 17) in addition to data for samples taken directly from females (N = 139). Second, we employed assignment methods in addition to the more traditional F‐statistics. No significant genetic structure could be demonstrated with FST. However, when average assignment probabilities of females were examined, those for nesting populations in which they were sampled were indeed significantly higher than their probabilities for other populations (Mann–Whitney U‐test: P < 0.001). Further evidence was provided by a significant result for the mAIC test (P < 0.001), supporting greater natal philopatry for females compared with males. The results suggest that female natal site fidelity was not sufficient for significant genetic differentiation among the nesting populations within the rookery, but detectable with assignment tests.
Phylogeography of the Ryukyu robin (Erithacus komadori): population subdivision in land‐bridge islands in relation to the shift in migratory habit
Authors: SEKI SHIN‐ICHI , SAKANASHI MASAHIKO , KAWAJI NORITOMO , KOTAKA NOBUHIKO
Published: December 2006

We analysed the mitochondrial control region sequences of 150 Ryukyu robins (Erithacus komadori) from five migratory and three sedentary populations. E. komadori is endemic to the subtropical Asian islands, is well differentiated among populations in morphology and migratory behaviour within its narrow habitat range, and is ideal for examining the effects of altered migratory habits on population differentiation. Maximum‐likelihood analysis among the haplotypes resulted in the generation of a single tree in which two phylogenetic clades corresponding to the two subspecies were evident. Within the northern lineage, three distinctive subgroups of populations (one migratory and two sedentary groups) were observed by population genetic analysis. The migration‐related wing morphology and molecular data were then compared among groups. The wing shape of the northern lineage was significantly more pointed than that of the southern sedentary lineage, and they were exclusively discriminated from each other. The difference was not so apparent between the sedentary and migratory groups within the northern lineage, suggesting that the present northern subspecies is primarily a migratory lineage. The different migratory behaviours of the robin played an apparent role in maintaining the genetic structure at two different levels — one between the southern and northern lineages and the other between the sedentary and migratory groups within the northern lineage. While gene flow had long been maintained among the islands occupied by migratory individuals, migrants have been unable to contribute to the gene pool of the sedentary populations despite passing through the breeding range of such populations twice each year.
Concordance of allozyme and microsatellite differentiation in a marine fish, but evidence of selection at a microsatellite locus
Authors: LARSSON LENA C. , LAIKRE LINDA , PALM STEFAN , ANDRÉ CARL , CARVALHO GARY R. , RYMAN NILS
Published: December 2006

Previous studies have reported higher levels of divergence for microsatellites than for allozymes in several species, suggested to reflect stabilizing selection on the allozymes. We compared the differentiation patterns of 11 allozyme and nine microsatellite loci using 679 spawning Atlantic herring (Clupea harengus) collected in the Baltic and North Seas to test for differential natural selection on these markers. Observed distributions of F statistics for the two types of markers are conspicuously dissimilar, but we show that these differences can largely be explained by sampling phenomena caused by different allele frequency distributions and degrees of variability. The results show consistently low levels of differentiation for both marker types, with the exception of one outlier microsatellite locus with a notably high FST. The aberrant pattern at this locus is primarily due to two alleles occurring at markedly high frequencies in the Baltic, suggesting selection at this locus, or a closely linked one. When excluding this locus, the two marker types show similar, weak differentiation patterns with FST values between the Baltic and the North Seas of 0.001 and 0.002 for allozymes and microsatellites, respectively. This small heterogeneity, and weak isolation by distance, is easier to distinguish statistically with microsatellites than with allozymes that have fewer alleles and skewed frequency distributions. The allozymes, however, also detect surprisingly low levels of divergence. Our results support suggestions that previously described differences between marker types are primarily caused by a small number of outlier loci.
The Lyme disease agent Borrelia burgdorferi requires BB0690, a Dps homologue, to persist within ticks
Authors: Li Xin , Pal Utpal , Ramamoorthi Nandhini , Liu Xianzhong , Desrosiers Daniel C. , Eggers ChristiaN. H. , Anderson John F. , Radolf Justin D. , Fikrig Erol
Published: December 2006

Borrelia burgdorferi survives in an enzootic cycle, and Dps proteins protect DNA against damage during starvation or oxidative stress. The role of a Dps homologue encoded by Borrelia in spirochaete survival was assessed. Dps‐deficient spirochaetes were infectious in mice via needle‐inoculation at the dose of 105 spirochaetes. Larval ticks successfully acquired Dps‐deficient spirochaetes via a blood meal on mice. However, after extended periods within unfed nymphs, the Dps‐deficient spirochaetes failed to be transmitted to a new host when nymphs fed. Our data suggest that Dps functions to protect the spirochaetes during dormancy in unfed ticks, and in its absence, the spirochaetes become susceptible during tick feeding. dps is differentially expressed in vivo– low in mice and high in ticks – but constitutively expressed in vitro, showing little change during growth or in response to oxidative stress. Borrelia Dps forms a dodecameric complex capable of sequestering iron. The Dps‐deficient spirochaetes showed no defect in starvation and oxidative stress assays, perhaps due to the lack of iron in spirochaetes grown in vitro. Dps is critical for spirochaete persistence within ticks, and strategies to interfere with Dps could potentially reduce Borrelia populations in nature and thereby influence the incidence of Lyme disease.
A qualitative host‐pathogen interaction in the Theobroma cacao‐Moniliophthora perniciosa pathosystem
Authors: Shaw M. W. , Vandenbon A. E.
Published: December 2006

The aim of this study was to test whether resistance of clones of Theobroma cacao (cocoa) varied between isolates of Moniliophthora (formerly Crinipellis) perniciosa, the cause of witches’ broom disease. Developing buds of vegetatively propagated T. cacao grown in greenhouses in the UK were inoculated with 16 000 spores of M. perniciosa per meristem in water, under conditions where water condensed on the inoculated shoot for at least 12 h after inoculation. The proportion of successful inoculations varied between clones and was inversely correlated with time to symptom production or broom formation. A specific interaction was demonstrated among three single‐spore isolates of M. perniciosa and the clone Scavina 6 (SCA 6) and a variety of susceptible clones. Isolates Castenhal‐I and APC3 were equally likely to infect SCA 6 and the other clones, but isolate Gran Couva A9 never infected SCA 6, although it was as virulent on the other clones. The interaction was maintained when the wetness period was extended to 70 h. Offspring of SCA 6 × Amelonado matings were all susceptible to both Castenhal‐I and GC‐A5, with no evidence of greater variability in susceptibility to GC‐A5 than Castanhal‐I. This suggests recessive inheritance of a single homozygous factor conferring resistance to GC‐A5, from SCA 6. The progenies were slightly more susceptible to Castanhal‐I than GC‐A5. The implications for managing the disease are discussed.
Phenotypic and genetic variation in Finnish potato‐late blight populations, 1997–2000
Authors: Lehtinen A. , Hannukkala A. , Rantanen T. , Jauhiainen L.
Published: December 2006

This study was conducted on potato late blight samples collected for monitoring early attacks in Finland from 1997 to 2000. Most of the 1726 Phytophthora infestans isolates were collected soon after the onset of the epidemics. Most of the isolates were tested for mating type as well as metalaxyl and propamocarb hydrochloride (HCl) sensitivity, while virulence on potato R‐gene differentials and mitochondrial DNA (mtDNA) haplotype were determined for a subset of the isolates. In half of the fields from which more than one isolate was tested, both mating types were detected, indicating strong potential for sexual reproduction. The mating types coexisted more often in organic fields or gardens than in conventional fields. The proportion of A1 mating type decreased from approximately 80% (1997 and 1998) to 22% by the year 2000. Simultaneously, the proportion of isolates resistant to metalaxyl decreased from approximately 40% to 16%. Resistance to metalaxyl was confined to the IIa mtDNA haplotype and clearly associated with the A1 mating type, as resistance was 10 times more common among A1 isolates than among A2 isolates. Resistance to metalaxyl therefore probably derives from common descent from an isolate with the IIa haplotype. Most of the regional variation in metalaxyl sensitivity was also linked to mating type, as both metalaxyl resistance and the A1 mating type were most common in the north and south‐west of Finland. In contrast to metalaxyl, only three propamocarb‐HCl‐insensitive isolates were found, but propamocarb‐HCl sensitivity decreased significantly during the study.
Genomic imprinting, methylation and molecular evolution of maize Enhancer of zeste (Mez) homologs
Authors: Haun William J. , Laoueillé‐Duprat Sylvia , O'Connell Mary J. , Spillane Charles , Grossniklaus Ueli , Phillips Allison R. , Kaeppler Shawn M. , Springer Nathan M.
Published: December 2006

Imprinted gene expression refers to differential transcription of alleles depending on their parental origin. To date, most examples of imprinted gene expression in plants occur in the triploid endosperm tissue. The Arabidopsis gene MEDEA displays an imprinted pattern of gene expression and has homology to the Drosophila Polycomb group (PcG) protein Enhancer‐of‐zeste (E(z)). We have tested the allele‐specific expression patterns of the three maize E(z)‐like genes Mez1, Mez2 and Mez3. The expression of Mez2 and Mez3 is not imprinted, with a bi‐allelic pattern of transcription for both genes in both the endosperm and embryonic tissue. In contrast, Mez1 displays a bi‐allelic expression pattern in the embryonic tissue, and a mono‐allelic expression pattern in the developing endosperm tissue. We demonstrate that mono‐allelic expression of the maternal Mez1 allele occurs throughout endosperm development. We have identified a 556 bp differentially methylated region (DMR) located approximately 700 bp 5′ of the Mez1 transcription start site. This region is heavily methylated at CpG and CpNpG nucleotides on the non‐expressed paternal allele but has low levels of methylation on the expressed maternal allele. Molecular evolutionary analysis indicates that conserved domains of all three Mez genes are under purifying selection. The common imprinted expression of Mez1 and MEDEA, in concert with their likely evolutionary origins, suggests that there may be a requirement for imprinting of at least one E(z)‐like gene in angiosperms.
A high‐performance, small‐scale microarray for expression profiling of many samples in Arabidopsis–pathogen studies
Authors: Sato Masanao , Mitra Raka M. , Coller John , Wang Dong , Spivey Natalie W. , Dewdney Julia , Denoux Carine , Glazebrook Jane , Katagiri Fumiaki
Published: December 2006

Studies of the behavior of biological systems often require monitoring of the expression of many genes in a large number of samples. While whole‐genome arrays provide high‐quality gene‐expression profiles, their high cost generally limits the number of samples that can be studied. Although inexpensive small‐scale arrays representing genes of interest could be used for many applications, it is challenging to obtain accurate measurements with conventional small‐scale microarrays. We have developed a small‐scale microarray system that yields highly accurate and reproducible expression measurements. This was achieved by implementing a stable gene‐based quantile normalization method for array‐to‐array normalization, and a probe‐printing design that allows use of a statistical model to correct for effects of print tips and uneven hybridization. The array measures expression values in a single sample, rather than ratios between two samples. This allows accurate comparisons among many samples. The array typically yielded correlation coefficients higher than 0.99 between technically duplicated samples. Accuracy was demonstrated by a correlation coefficient of 0.88 between expression ratios determined from this array and an Affymetrix GeneChip, by quantitative RT–PCR, and by spiking known amounts of specific RNAs into the RNA samples used for profiling. The array was used to compare the responses of wild‐type, rps2 and ndr1 mutant plants to infection by a Pseudomonas syringae strain expressing avrRpt2. The results suggest that ndr1 affects a defense‐signaling pathway(s) in addition to the RPS2‐dependent pathway, and indicate that the microarray is a powerful tool for systems analyses of the Arabidopsis disease‐signaling network.
HLA‐A, ‐B, ‐C, ‐DRB1 allele and haplotype frequencies in an African American population
Authors: Tu B. , Mack S. J. , Lazaro A. , Lancaster A. , Thomson G. , Cao K. , Chen M. , Ling G. , Hartzman R. , Ng J. , Hurley C. K.
Published: December 2006

Sequence‐based typing was used to identify human leukocyte antigen (HLA)‐A, ‐B, ‐C, and ‐DRB1 alleles from 564 consecutively recruited African American volunteers for an unrelated hematopoietic stem cell registry. The number of known alleles identified at each locus was 42 for HLA‐A, HLA‐B 67, HLA‐C 33, and HLA‐DRB1 44. Six novel alleles (A*260104, A*7411, Cw*0813, Cw*1608, Cw*1704, and DRB1*130502) not observed in the initial sequence‐specific oligonucleotide probe testing were characterized. The action of balancing selection, shaping more ‘even’ than expected allele frequency distributions, was inferred for all four loci and significantly so for the HLA‐A and DRB1 loci. Two‐, three‐, and four‐locus haplotypes were estimated using the expectation maximization algorithm. Comparisons with other populations from Africa and Europe suggest that the degree of European admixture in the African American population described here is lower than that in other African American populations previously reported, although HLA‐A:B haplotype frequencies similar to those in previous studies of African American individuals were also noted.
Variation in copper tolerance in Arabidopsis thaliana accessions Columbia, Landsberg erecta and Wassilewskija
Authors: Schiavon Michela , Zhang Lihong , Abdel‐Ghany Salah E. , Pilon Marinus , Malagoli Mario , Pilon‐Smits Elizabeth A. H.
Published: December 2006

Among the Arabidopsis thaliana accessions Columbia (Col), Landsberg erecta (Ler), and Wassilewskija (Ws), Ler and Ws showed higher copper (Cu) tolerance than Col, while accumulating more Cu. Thus, Cu tolerance did not appear to be related to metal exclusion. Rather, the higher Cu tolerance of Ler and Ws may reflect less Cu‐induced nutrient deficiency as they maintained higher sulfur, iron (Fe), and manganese levels than Col under Cu stress. Reverse transcription–polymerase chain reaction was used to compare the leaf transcript levels of nine genes involved in Cu metabolism, oxidative stress resistance or sulfate transport (Sultr 4;1). Excess Cu led to an overall decrease of the transcript levels of plastocyanin and two plastidic Cu transporters, PAA1 and PAA2. The Fe superoxide dismutase (SOD) gene FSD1 was also downregulated in the three accessions, while the cytosolic Cu/Zinc SOD (CSD1) was upregulated compared with the control conditions. These results may be related to differences in Fe and Cu accumulation. The transcript abundance of the Cu chaperones ATX1, CCS and CpCCP showed differential regulation among the three accessions in response to Cu supply. The vacuolar Sultr 4;1 was upregulated by Cu, most likely due to the lower ability to accumulate S. Total non‐protein thiol levels were not correlated with Cu tolerance.
The BIG gene is involved in regulation of sulfur deficiency‐responsive genes in Arabidopsis thaliana
Authors: Kasajima Ichiro , Ohkama‐Ohtsu Naoko , Ide Yoko , Hayashi Hiroaki , Yoneyama Tadakatsu , Suzuki Yoshihito , Naito Satoshi , Fujiwara Toru
Published: December 2006

The Arabidopsis thaliana mutants altered sulfur response 1‐1 (asr1‐1) and asr1‐2 were isolated using the green fluorescent protein gene (GFP), as a marker, driven by a sulfur deficiency‐responsive promoter containing the βSR fragment, which is responsible for the induction of gene expression under sulfur deficiency. In the asr1 mutants, the expression of three sulfur deficiency‐responsive genes βSR‐driven GFP, sulfate transporter 2;2 (SULTR2;2) and adenosine‐5′‐phosphosulfate reductase 1 (APR1) were induced in medium containing a normal sulfate concentration. The ASR1 locus was mapped to a 53‐kb region on the upper arm of chromosome III; this is also the region of the BIG gene, which encodes a calossin‐like protein necessary for the polar transport of auxin. The morphology of the asr1 mutants, i.e. reduced leaf size and inflorescence elongation, resembled that of big mutants. Using nucleotide sequence analysis of the BIG gene, we identified independent nonsense mutations in asr1‐1 and asr1‐2. To confirm that ASR1 was BIG, we established lines of transgenic A. thaliana carrying a transfer DNA (T‐DNA) insertion in the BIG gene. In these T‐DNA insertion mutants, mRNA levels of βSR‐driven GFP and APR1 were upregulated in normal sulfate medium. The F1 plants from crosses between asr1‐1 and T‐DNA insertion lines exhibited reduced leaf size and inflorescence length, indicating that ASR1 was indeed BIG. Taken together, the present results established that BIG is involved in the regulation of βSR‐driven GFP and APR1 mRNA level gene expression. Indole‐3‐acetic acid also upregulated βSR‐driven GFP and APR1 together with SULTR2;2 mRNA level, suggesting that the big effect on βSR‐driven GFP and APR1 is a pleiotropic aspect of the BIG gene.
Changes in photosynthesis and antioxidant defenses ofPicea asperataseedlings to enhanced ultraviolet‐B and to nitrogen supply
Authors: Yao Xiaoqin , Liu Qing
Published: December 2006

The paper mainly studied the effects of ultraviolet‐B (UV‐B) radiation, nitrogen, and their combination on photosynthesis and antioxidant defenses ofPicea asperataseedlings. The experimental design included two levels of UV‐B treatments (ambient UV‐B, 11.02 KJ m−2day−1; enhanced UV‐B, 14.33 KJ m−2day−1) and two nitrogen levels (0; 20 g m−2a−1N) – to determine whether the adverse effects of UV‐B are eased by supplemental nitrogen. Enhanced UV‐B significantly inhibited plant growth, net photosynthetic rate (A), stomatal conductance to water vapor (Gs), transpiration rate and photosynthetic pigment, and increased intercellular CO2concentration, UV‐B absorbing compounds, proline content, malondialdehyde (MDA) content, and activity of antioxidant enzymes (peroxidase (POD), superoxide dimutase, and glutathione reductase). Enhanced UV‐B also reduced needle DW and increased hydrogen peroxide (H2O2) content and the rate of superoxide radical (O2−) production only under supplemental nitrogen. On the other hand, supplemental nitrogen increased plant growth, A, Gs, chlorophyll content and activity of antioxidant enzymes (POD, ascorbate peroxidase, and catalase), and reduced MDA content, H2O2content, and the rate of O2−production only under ambient UV‐B, whereas supplemental nitrogen reduced activity of antioxidant enzymes under enhanced UV‐B. Carotenoids content, proline content, and UV‐B absorbing compounds increased under supplemental nitrogen. Moreover, significant UV‐B × nitrogen interaction was found on plant height, basal diameter, A, chlorophylla, activity of antioxidant enzymes, H2O2, MDA, and proline content. These results implied that supplemental nitrogen was favorable for photosynthesis and antioxidant defenses ofP.asperataseedlings under ambient UV‐B. However, supplemental nitrogen made the plants more sensitive to enhanced UV‐B, although some antioxidant indexes increased.
Enhanced systemic resistance to bacterial speck disease caused by Pseudomonas syringae pv. tomato by dl‐β‐aminobutyric acid under salt stress
Authors: Baysal Ömür , Gürsoy Y. Ziya , Örnek Hakan , Çetinel Barbaros , Teixeira da Silva Jaime A.
Published: December 2006

Plants have evolved different but interconnected strategies to defend themselves against microbial pathogens and stress conditions. The defense responses of tomato (Lycopersicon esculentum Mill) seedlings treated with dl‐β‐aminobutyric acid (BABA) were investigated with and without abiotic stress (100 mM NaCl) against bacterial speck disease caused by Pseudomonas syringae pv. tomato. The plants were sprayed with 50, 125, 250 or 500 μg ml−1 BABA and were inoculated with 108 colony‐forming units ml−1 bacterial suspension 1 day after treatment. Abiotic stress led to an increase in plant resistance. When BABA was additionally applied as a foliar spray at 125 μg ml−1, the effect on plants was almost identical to that on plants that were sprayed with BABA at 500 μg ml−1 alone. The bacterial multiplication in the plants was 250‐fold lower than in the water‐treated (control) plants and in plants that were sprayed with 500 μg ml−1 BABA alone within 48 h postinoculation (hpi). Physiological studies were carried out in the plants treated with BABA in order to investigate the reason for this synergistic effect. Abiotic stress with BABA spray resulted in high H2O2 generation and guaiacol peroxidase activity in the plants. The activity of the enzymatic antioxidative protective system of the plants, superoxide dismutase, ascorbate peroxidase and catalase (CAT), also showed a significant delayed increase in BABA‐treated plants under abiotic stress conditions. These increases in enzyme activity coincided with the initiation of the most suppressive effect of BABA on bacterial growth by 24 hpi, which were significantly higher than the control. Salt stress alone did not lead to any significant increase in CAT activity, but salt stress with BABA did. These findings indicate a synergistic effect between salt stress and BABA at low concentrations, resulting in induced plant resistance. Furthermore, a stress regulation effect of BABA under abiotic stress can be associated with plant resistance.
Cadmium responses in Arabidopsis thaliana: glutathione metabolism and antioxidative defence system
Authors: Semane Brahim , Cuypers Ann , Smeets Karen , Van Belleghem Frank , Horemans Nele , Schat Henk , Vangronsveld Jaco
Published: December 2006

We investigated the effect of cadmium (Cd) on leaves of 3‐week‐old Arabidopsis thaliana with a particular interest on glutathione (GSH) production and consumption, and antioxidative defence. Plants were exposed to either 1 or 10 μM Cd for 1 week. Several genes and correspondent proteins known to participate in the regulation of redox states in plants were analysed in Cd‐stressed and unstressed plants. Cd induced a significant increase in the messenger RNA level of genes involved in GSH synthesis (gsh1 and gsh2) and phytochelatin synthase (pcs1). We observed a significant decrease of reduced GSH in Cd‐treated plants. In parallel, an increase of phytochelatin (PC), predominantly PC2 was observed. Cd treatment increased the accumulation of glutathione disulphide (GSSG), keeping the GSH/GSSG ratio lower than in control plants. The accumulation of GSSG was accompanied by a decrease of the glutathione reductase (gr) transcript level, while the activities of GR and nicotinamide nucleotide phosphate‐reducing enzymes were significantly enhanced. The antioxidative defence mechanism related to the ascorbate (AsA)–GSH cycle was studied in parallel. A general increase of reactive oxygen species scavenging enzymes such as ascorbate peroxidase, catalase or superoxide dismutase was observed. Our data suggest that the plants respond to Cd stress by the AsA–GSH defence network at both transcriptional and enzymatic level. Taken together, it appears that Arabidopsis plants exposed to 1 μM Cd were able to adopt a new metabolic equilibrium, allowing them to cope with this metal. However, when exposed to 10 μM Cd, loss of cellular redox homeostasis resulted in oxidative stress and toxicity.
Differential regulation of cadmium‐inducible expression of iron‐deficiency‐responsive genes in tobacco and barley
Authors: Hodoshima Hirotaka , Enomoto Yusuke , Shoji Kazuhiro , Shimada Hiroaki , Goto Fumiyuki , Yoshihara Toshihiro
Published: December 2006

The expression of four representative iron‐deficiency‐responsive genes from tobacco (NtIRT1 and NtYSL1) and barley (HvIDS2 and HvYS1) plants were evaluated in each host plant in response to iron deficiency (ΔFe), cadmium exposure (+Cd) or both (ΔFe + Cd). These conditions significantly enhanced NtIRT1 and HvIDS2 expression in roots, whereas NtYSL1 and HvYS1 expression was similar in shoots and roots. NtIRT1 expression under +Cd and ΔFe + Cd was lower than that under ΔFe, whereas the expression of NtYSL1, HvIDS2 and HvYS1 in roots under +Cd and ΔFe + Cd was similar or higher than that under ΔFe. A time‐course experiment showed that NtIRT1 expression under +Cd and ΔFe was regulated similarly throughout the experiment [expressed between 3 and 21 days after treatment (DAT)]. NtYSL1 expression under +Cd and ΔFe began at 1 DAT; expression soon disappeared under ΔFe, whereas it continued to 21 DAT under +Cd. The timing of HvIDS2 and HvYS1 expression under +Cd (between 1 and 5 DAT) was earlier than that under ΔFe (between 5 and 21 DAT). Notably, no Fe deficit occurred in any parts of these plants when grown under +Cd, except for tobacco shoots, even when the genes were highly expressed. Thus, some expression under +Cd differed from that under ΔFe. It is possible that both the genuine Fe‐deficiency‐responsive mechanism and an unidentified mechanism, which can be directly regulated by Cd, contribute to gene expression to maintain metal homeostasis within the plant.
The role of CBF transcriptional activators in two Citrus species (Poncirus and Citrus) with contrasting levels of freezing tolerance
Authors: Champ Karen I. , Febres Vicente J. , Moore Gloria A.
Published: December 2006

Citrus species are considered cold sensitive, yet Poncirus trifoliata, an interfertile Citrus relative, is extremely cold tolerant and can survive freezes at −20°C when fully cold acclimated. To better understand the molecular basis of this difference in freezing tolerance, C‐repeat‐binding factors (CBFs) from P. trifoliata and Citrus paradisi (grapefruit) were isolated and characterized. Based on our results, P. trifoliata and C. paradisi do contain a CBF pathway for cold‐regulated gene expression, and similar to other species, they both appear to contain small CBF families. The nucleotide and amino acid sequences of PtCBF1 and CpCBF1 are highly homologous. However, differences in cold‐induced expression were observed. PtCBF1 accumulates both earlier and to higher levels than CpCBF1. Furthermore, CORc115, a cold‐induced group II LEA gene, also accumulates earlier and to higher levels in P. trifoliata in response to cold temperatures. The regulatory region of CORc115 contains a putative C‐repeat/dehydration‐responsive element that is specifically recognized and bound by PtCBF, indicating that CORc115 is a target of PtCBF1. This study provides the first evidence of a correlation between CBF expression (timing and quantity) and the degree of cold tolerance in two closely related species with wide differences in cold tolerance. The importance of using Poncirus and Citrus, two non‐model organisms, to address new questions about the CBF pathway is illustrated, as these results provide novel evidence that the CBF expression pattern may play an important role in the notable difference in cold tolerance between these two related species.
Antibody therapy (IVIG): evaluation of the use of genomics and proteomics for the study of immunomodulation therapeutics
Authors: Sapan C. V. , Reisner H. M. , Lundblad R. L.
Published: December 2006

Background and Objectives Intravenous immunoglobulin (IVIG) is used for an increasingly diverse number of therapeutic applications as an immunomodulation drug. Although it has demonstrated therapeutic effectiveness, the mechanism of action of IVIG in these disorders is poorly understood; this lack of understanding complicates rational clinical application and reimbursement for ‘off‐label’ use.

Materials and Methods Selected literature on the clinical use of IVIG as an immunomodulation drug is reviewed. We present a brief description of DNA microarray and protein microarray technology and the application of such technologies to the study of immune system cells. The several studies on the application of DNA microarray technology to study gene expression in response to IVIG are presented.

Results There is increasing data on the use of DNA microarray and protein microarray technology to study gene expression in immune system cells including T cells, B cells, macrophages, and leucocytes. There is less information on the effect of IVIG on gene expression in immune system cells. However, there is sufficient information available to suggest that this is a practical approach with the caveat that such work will require careful experimental design and clear definition of the normal population.

Conclusions DNA and protein microarray assays can be used to (i) provide rational indications for the clinical use of IVIG, (ii) provide for specific analysis of raw material and end product IVIG in screening for content related to immunomodulation, and (iii) accelerate the development of next generation products which would be more focused and/or targeted therapeutics.
Variability of parvovirus B19 to inactivation by liquid heating in plasma products
Authors: Hattori S. , Yunoki M. , Tsujikawa M. , Urayama T. , Tachibana Y. , Yamamoto I. , Yamamoto S. , Ikuta K.
Published: December 2006

Background and Objectives  Previously, we reported that although human parvovirus B19 in albumin and intravenous immunoglobulin preparations was rapidly inactivated during liquid heating, in contrast to other parvoviruses such as canine parvovirus, sensitivity to heat was highly dependent on the composition of the solution. In this study, we aimed to further elucidate the sensitivity to heat of B19 in haptoglobin and antithrombin (previously named antithrombin III) preparations during liquid heating.

Materials and Methods  Two different solutions collected immediately before heat treatment of haptoglobin and antithrombin preparations were spiked with B19 and subsequently treated at 60 °C for 10 h. B19 DNA‐positive, anti‐B19 IgG/IgM‐negative plasma was used as a source of B19. The residual infectivity in each sample was measured using a B19 cell‐based infectivity assay with an mRNA polymerase chain reaction.

Results  B19 in different plasma preparations showed different heat‐sensitivity patterns during liquid heating: (i) slow inactivation in haptoglobin preparations, and (ii) only limited inactivation in antithrombin preparations. The kinetics of inactivation was greatly different from that in our previous studies in which the virus was shown to be rapidly inactivated in albumin and intravenous immunoglobulin preparations.

Conclusion  B19 has unique properties in terms of heat sensitivity, depending on the composition of the solution during liquid heating. This finding may indicate the need for caution when interpreting the sensitivity of B19 to heat.
Changes in the Muscle Fibre Properties of the Mouse Temporal Muscle after Weaning
Authors: Suzuki K. , Abe S. , Kim H. J. , Usami A. , Iwanuma O. , Okubo H. , Ide Y.
Published: December 2006

To clarify changes in the muscle fibre properties of the temporal muscle related to the start of masticatory movement, we immunohistochemically investigated myosin heavy chain (MyHC) isoform protein expression using pre‐weaning and post‐weaning mice. In addition, we examined the expression of a gene coding for those MyHC proteins. Immediately after weaning, isoforms with fast and potent contractility were frequent. This suggests that the temporal muscle plays an important role in a marked functional change in the oral cavity from lactation to mastication, contributing to oral function in cooperation with other masticatory muscles.
The Ets‐1 Transcription Factor is Involved in Pterygial Angiogenesis
Authors: Naib‐Majani W. , Breipohl W. , Shazli E. E. , Theuerkauf I. , Pleyer U. , Hahne J. C. , Wernert N.
Published: December 2006

Pterygial pathology is characterized by abnormal corneal epithelial proliferation, stromal modulation, matrix degradation and a strong tendency for otherwise absent corneal vascularization. As the proto‐oncogene Ets‐1 is known to play a key role in angiogenesis and matrix degradation in other tissues, its involvement in corneal vascularization was investigated. Fifteen pterygia representing two groups were studied. Group 1 consisted of five clinically active pterygia, and group 2 consisted of 10 samples of clinically non‐active pterygia. 35S‐labelled ets‐1 antisense and sense riboprobes were used for in‐situ hybridization of Ets‐1 transcription factor in all pterygia. The cytoplasm of blood vessel endothelial cells showed strong expression of ets‐1 mRNA in all group 1 pterygia. In contrast, no expression of ets‐1 was found in group 2 pterygia. Proto‐oncogene ets‐1 expression has been shown for the first time in the metaplastic pterygium, an eye tissue of unknown pathogenesis.
Expression of Nitric Oxide Synthase Isoforms in the Testes of Pigs
Authors: Kim H. C. , Byun J. S. , Lee T. K. , Jeong C. W. , Ahn M. , Shin T.
Published: December 2006

This study examined the expression of three isoforms of nitric oxide synthase (NOS) in the testes of pigs. Immunohistochemical studies demonstrated the presence of nNOS, eNOS and iNOS in interstitial cells, primary spermatocytes and spermatids. Positive immunoreactions for eNOS and iNOS were detected in peritubular myoid cells. Some vascular endothelial cells were positive for nNOS and eNOS. The expression of nitrotyrosine was detected in interstitial cells. In addition, the histochemical study revealed that all the interstitial cells were stained positively for NADPH‐diaphorase, although some spermatids and vascular endothelial cells displayed moderate enzymatic activity. These findings suggest that three isoforms of NOS are expressed in the testis of pig and that they play important roles in the biology of interstitial cells that produce testosterone, as well as in spermatogenesis in the seminiferous tubules.
The Distribution of Ganglion Cells in the Equine Retina and its Relationship to Skull Morphology
Authors: Evans K. E. , McGreevy P. D.
Published: December 2006

It has recently been reported that a strong correlation exists between the distribution of retinal ganglion cells and nose length in the domestic dog. To determine if this phenomenon occurs in another domestic species with diverse skull morphology, the current study examined the distribution of retinal ganglion cells in 30 horses from a variety of breeds. There was a significant variation in the density of ganglion cells found across the retinae. Breed was a significant predictor for ganglion cell density within the visual streak. A strong positive correlation exists between the density of ganglion cells in the visual streak and nasal length. Significant variation was also seen in the area centralis but did not correlate with any of the recorded skull measurements. The findings of this study provide us with further understanding of the equine visual system and the level of variation that exists between individuals of the same species.
Effect of Microbial Activity and Nitrogen Mineralization on Free‐living Nitrogen Fixation in Permanent Grassland Soils
Authors: Patra A. K. , Le Roux X. , Abbadie L. , Clays‐Josserand A. , Poly F. , Loiseau P. , Louault F.
Published: December 2006

Free‐living nitrogen (N) fixation can be important for sustainable soil fertility, particularly in extensively managed soils with low abundance of leguminous plant species. However, the factors affecting free N2‐fixation in situ are still poorly documented. We investigated the role of microbial active biomass activity, particularly substrate‐induced respiration (SIR) and net N mineralization, on the free‐living N2 fixation in soils under a semi‐natural grassland ecosystem in France. Analysis of replicated bulk soil and rhizospheric soil samples obtained from sites experiencing contrasting grazing regimes revealed highly significant negative relationships (P < 0.01) between free‐living N2‐fixation and SIR or N‐mineralization with a significant rhizosphere effect. The study has demonstrated that the activity of free‐living N2‐fixers is more important in soils having low active microbial biomass and low N‐mineralization rates in these permanent grasslands.
Determining Crop and Pan Coefficients for Sugar Beet and Potato Crops under Cool Season Semiarid Climatic Conditions
Authors: Sahin U. , Kiziloglu F. M. , Anapali O. , Okuroglu M.
Published: December 2006

This study was conducted in a region with semiarid cool climatic conditions during the period from May to October in the years 2003 and 2004, respectively. Actual evapotranspiration (ETc) of sugar beet and potato crops was calculated according to the water balance approach. Reference evapotranspiration (ETo) was calculated with FAO Penman–Monteith equation. Evaporation (Epan) was measured by using class A pan. Seasonal mean ETcwas determined as 492.9 mm for sugar beet and 445.2 mm for potato. Seasonal mean pan coefficient (kp = ETo/Epan) was determined as 0.74, and the seasonal mean crop coefficient (kc = ETc/ETo) was determined as 0.65 for sugar beet 0.60 for potato.