bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of the variable charge of two organic soils by means of the NICA‐Donnan model
Authors: Vasiliadis B. , Antelo J. , Iglesias A. , López R. , Fiol S. , Arce F. 
Published: July 2007

SummaryWe have tested to see if the generic set of NICA‐Donnan model parameters, used to describe isolated humic substances, can also describe soil humic substances in situ. A potentiometric back‐titration technique was used to determine the variable surface charge of two organic peat soils at three different ionic strengths. The non‐ideal, competitive‐adsorption NICA‐Donnan model was used to simulate the surface charge, by assuming a bimodal distribution of H+ affinity on the soil solid phase. The model provided an excellent fit to the experimental data. The Donnan volume, VD, varied slightly with ionic strength, although the variation was less than for humic substances in solution. The values obtained for the parameters that define the affinity distributions, the intrinsic proton binding constant (log Kiint) and the heterogeneity of the site (mi), were similar to those observed for isolated soil humic acids. The abundance of carboxylic groups in the whole soil represented 30% of the typical value for isolated soil humic acids. The composition of the organic matter of the whole soils, obtained by 13C CPMAS NMR, was comparable to the characteristic composition of soil humic acids.
Androgen receptor gene haplotype is associated with male infertility
Authors: Saare M. , Belousova A. , Punab M. , Peters M. , Haller K. , Ausmees K. , Poolamets O. , Karro H. , Metspalu A. , Salumets A. 
Published: July 2007

SummaryThe purpose of the current study was to evaluate the importance of androgen receptor (AR) gene haplotypes and polymorphic CAG/GGN microsatellites in the aetiology of male infertility. We genotyped six haplotype‐tagging single nucleotide polymorphisms and CAG/GGN microsatellites of theARgene in 112 infertile and 212 control Estonian men. A total of 13ARhaplotypes (HAP1–13) were identified, among which HAP4 was found to confer increased risk for male infertility (OR = 5.15, 95% CI = 1.75–15.15,p = 0.003). However, infertile patients and controls had similar lengths and distributions of bothARCAG (mean ± SD number of repeats 21.1 ± 2.5 vs.21.2 ± 2.3, respectively) and GGN (mean ± SD number of repeats 22.5 ± 1.5 vs.22.4 ± 1.9, respectively) repeats. In addition, HAP2 was associated with more CAG repeats (r = 1.17,p = 0.033) and HAP3 with fewer CAG repeats (r = −2.93,p < 0.001) than the major haplotype HAP1. HAP3 and HAP4 were associated with more GGN repeats (r = 1.35,p = 0.001 andr = 1.36,p = 0.002, respectively) than HAP1. In conclusion, our results implicated theAR‐HAP4 gene haplotype in increased risk for male infertility, while no association was found betweenARCAG/GGN microsatellites and impaired spermatogenesis.
Influence of moderate cycling on scrotal temperature
Authors: Jung A. , Strauß P. , Lindner H. J. , Schuppe H. C. 
Published: July 2007

SummaryTesticular temperature highly correlates with scrotal temperature. It has been postulated that cycling is associated with increased scrotal temperatures with time and consecutively with impaired semen quality. The aim of this study was to evaluate the influence of moderate cycling on scrotal temperature during highly standardized conditions in an experimental lab. A total of 25 volunteers without a history of infertility and normal andrological examination were included for scrotal temperature evaluation. Scrotal temperatures were measured every minute with a portable data recorder connected with two thermistor temperature sensors, which were attached on either side of the scrotum. A further thermistor sensor was attached on the central surface of the bicycle saddle. Ambient temperature in the study room was adjusted to 22 °C throughout the whole experiment. All volunteers started the experiment at the same daytime. Clothing of the volunteers consisted of standardized cotton wool trousers and shirts fitting to body size. After acclimatization to the study room in a sitting posture, each volunteer cycled on an exercise cycle for 60 min with a power of 25 Watt representing a speed of 25.45 km/h respectively. The saddle surface temperature reached in the median 35.59 °C after 60 min cycling. Median values of scrotal temperatures increased from 35.75 °C at the beginning to 35.82 °C after 60 min for the left side and from 35.50 to 35.59 °C for the right side. No correlation between cycling duration and scrotal temperatures could be found using multivariateanovafor repeated measurements. However, scrotal temperatures during cycling were significantly lower (p < 0.001) compared with the last 10 min in sitting posture before starting cycling with a difference of 1.31 °C for the left and 1.46 °C for the right side. The present study suggests that moderate cycling under standardized conditions with a power of 25 Watt is not a major genital heat stress factor.
Penile vascular evaluation and sexual function before and after radical retropubic prostatectomy: 5‐year follow‐up
Authors: Dubbelman Yvette D. , Wildhagen Mark F. , Dohle Gert R. 
Published: July 2007

SummarySexual dysfunction is common after surgery for prostate cancer. The aetiology of changes in sexual potency after radical prostatectomy is probably multifactorial, including neurogenic, vascular and psychosexual factors. A prospective study was designed to investigate haemodynamic and psychosexual changes before and after radical retropubic prostatectomy (RRP) for organ‐confined prostate cancer. Penile haemodynamic evaluation and an assessment of sexual excitement were performed preoperatively and 3 months after RRP by colour Doppler ultrasonography (CDU) with visual erotic stimulation combined with a single intracavernous injection of a mixture of papaverine/phentolamine. Questionnaires on sexual function [International Index of Erectile Function (IIEF)], general health and quality of life were sent to the patients preoperative, 3 months and 5 years after operation. Forty‐eight men participated in the study. Mean age was 62.6 years (range 55–69). CDU did not show any significant reduction in mean peak systolic flow velocity and mean resistance index. From the men who preoperatively had normal arterial inflow 18% developed arteriogenic insufficiency. Some form of veno‐occlusive insufficiency and low resistance indices were already present in the majority of normal potent men preoperatively. Surgical technique did not influence penile arterial blood flow after the operation. Three months and 5 years postoperatively, there was a highly significant reduction in erectile function, intercourse satisfaction, overall satisfaction, orgasmic function and sexual desire. However, with respect to the outcome at 3 months there was a significant improvement of orgasmic function 5 years after operation, especially after a bilateral nerve sparing procedure. Erections sufficient for vaginal penetration (questions 3 and 4 of the IIEF, score ≥8) improved from 2% to 11% 3 months and 5 years after RRP respectively. Total IIEF score was significantly better after a bilateral nerve‐sparing procedure compared with non‐nerve sparing. No structural vascular changes were observed 3 months after operation. Vascular factors appear to be less important in the aetiology of ED after RRP. There seems to be a trend of a better improvement of sexual function over time, especially orgasmic function, in patients with bilateral nerve‐sparing surgery.
Psychological factors in male partners of infertile couples: relationship with semen quality and early miscarriage
Authors: Zorn B. , Auger J. , Velikonja V. , Kolbezen M. , Meden‐Vrtovec H. 
Published: July 2007

SummaryIn this study we sought to evaluate whether psychological factors in males affect semen quality and pregnancy. In 1076 men of infertile couples, psychological factors, i.e. exposure to acute stress, coping with stress, the WHO (five) Well‐Being Index and the Zung’s Anxiety Scale Inventory scores were assessed by a questionnaire at the time of semen analysis. Relationships between psychological factors and semen quality (sperm concentration, rapid and progressive motility and normal morphology) were assessed. In 353 men with infertility duration of ≤1.5 years, sperm concentration ≥5 × 106 sperm/mL and a female partner with a laparoscopically confirmed tubal patency, we looked prospectively for relations between psychological factors and the occurrence of a natural pregnancy at a 6‐month follow‐up (n = 124), and first‐trimester loss (n = 18). Anxiety trait, found in 19% of men, was related to previous in vitro fertilization/intracytoplasmic sperm injection attempts (p = 0.014), cigarette intake (p = 0.006), alcohol intake (p = 0.026) and sexual difficulties (p < 0.001). Regression analyses indicated a significant positive relationship between the level of sperm concentration and the WHO (five) Well‐Being Index score, each successive score number accounting for a 7.3% increase in sperm concentration (p = 0.039), whereas no correlation was found between psychological factors and sperm rapid progressive motility and normal morphology. Poorer coping with stress was related to the occurrence of a first‐trimester miscarriage (p = 0.016) in the female partner. Possible depression in males is related to decreased sperm concentration, and poor coping with stress is associated with increased occurrence of early miscarriage.
Highways as corridors and habitats for the invasive common reed Phragmites australis in Quebec, Canada
Authors: Jodoin Yvon , Lavoie Claude , Villeneuve Paul , Theriault Marius , Beaulieu Julien , Belzile François 
Published: July 2007

Summary

Roads provide suitable conditions for the establishment and growth of exotic species. Most roads are bordered by drainage ditches forming a network of linear wetlands. Drainage ditches may serve as habitats and corridors facilitating the spread of aquatic invaders into the intersected ecosystems. The common reed Phragmites australis is one of these aquatic invaders frequently found in marshes and drainage ditches along roads. We hypothesized that highways have acted as corridors for the dispersal of the common reed and have contributed to the invasion of North American wetlands by this species.
We mapped the spatial distribution of the common reed along the highway network of the province of Quebec, Canada, where a large‐scale invasion of this plant species has been reported since the 1960s. We also identified the genotype of common reed colonies using molecular tools and the main characteristics that favour the presence of the common reed in road ditches.
Approximately 67% of the 1359 1‐km highway sections surveyed during summer 2003 in Quebec had at least one common reed colony. End to end, common reed colonies totalled 324 km, i.e. 24% of the 1359 km surveyed.
Common reed colonies located along the highways were largely (99%) dominated by the exotic (Eurasian) genotype (haplotype M).
The common reed was more abundant along highways located in warm regions, with a sum of growing degree‐days (> 5 °C, 12‐month period) ≥ 1885, along highways built before the 1970s and in agricultural regions dominated by corn and soybean crops. Common reed colonies were larger when located along highways that were wide, built before the 1970s or in warm regions. This was particularly apparent if the roadside was bordered by a wetland. On the other hand, common reed colonies were more likely to be narrow when located near a woodland.
Synthesis and applications. Several disturbances (de‐icing salts, ditch digging and agricultural nitrogen input) favour the development of large common reed colonies along roads, some of them expanding out of roadsides, particularly in wetlands. Reducing disturbances, leaving (or planting) a narrow (a few metres) hedge of trees or shrubs along highways or planting salt‐resistant shrubs in roadside ditches could be efficient ways to slow the expansion of common reed or to confine the species to roadsides.
Floristic elements in European vascular plants: an analysis based onAtlas Florae Europaeae
Authors: Finnie Thomas J. R. , Preston Christopher D. , Hill Mark O. , Uotila P. , Crawley Michael J. 
Published: July 2007

AbstractAim To identify floristic elements in the European flora by an analysis of the distributions of species and species groups mapped inAtlas Florae Europaeae.Location Europe, as defined byFlora Europaea.Methods We analysed the native distributions of 2762 species and 33 species’ aggregates from 79 families, which representc.20% of the European flora. The distributional data base, derived fromAtlas Florae Europaeae, includes records from 4420 50 × 50‐km UTM grid squares. We classified species into floristic elements by a three‐stage clustering procedure, which consisted of: (1) constructing a dissimilarity hierarchy by complete linkage clustering, using a distance measure based on Jaccard’s coefficient; (2) cutting the hierarchical tree at the 0.95 level to create initial clusters, and forcing small clusters to link with larger ones until the sum of within‐group pairwise distances exceeded a threshold value; and (3) checking the allocation of all species to the redefined clusters and reassigning species if appropriate, using the cosine of the angle between the species and cluster centres to measure the similarity of species to clusters.Results The clustering procedure classified 2793 taxa into 18 floristic elements, which included between 66 and 289 taxa; two species had unique, non‐overlapping distributions and could not be classified.Main conclusions The analysis highlights the floristic diversity of the mountains of central and southern Europe, and of the Mediterranean region. The floristic elements of northern latitudes and the temperate lowlands tend to be composed of wide‐ranging species and include only a low proportion of European endemics. The montane elements, including those centred on montane areas in the Mediterranean region, are composed predominantly of perennial species and include high or very high proportions of European endemics. Classifications that recognize one ‘Alpine’ and one ‘Mediterranean’ biogeographical zone in Europe fail to reflect this floristic diversity.
An Arabidopsis MLH1 mutant exhibits reproductive defects and reveals a dual role for this gene in mitotic recombination
Authors: Dion Éric , Li Liangliang , Jean Martine , Belzile François 
Published: July 2007

SummaryThe eukaryotic DNA mismatch repair (MMR) system contributes to maintaining genome integrity and DNA sequence fidelity in at least two important ways: by correcting errors arising during DNA replication, and also by preventing recombination events between divergent sequences. This study aimed to investigate the role of one key MMR gene in recombination. We obtained a mutant line in which the AtMLH1 gene has been disrupted by the insertion of a T‐DNA within the coding region. Transcript analysis indicated that no full‐length transcript was produced in mutant plants. The loss of a functional AtMLH1 gene led to a significant reduction in fertility in both homozygotes and heterozygotes, and we observed a strong bias against transmission of the mutant allele. To investigate the role of AtMLH1 in mitotic recombination, the mutant was crossed to a series of recombination reporter lines. A strong decrease (72%) in the frequency of homologous recombination was observed in the mutant. However, the decline in recombination due to homeology was less severe in the Atmlh1 mutant than in a wild‐type control. These data demonstrate a dual role for AtMLH1 in recombination: it is both required for recombination and acts to limit recombination between diverged sequences.
MODULATOR OF PIN genes control steady‐state levels of Arabidopsis PIN proteins
Authors: Malenica Nenad , Abas Lindy , Benjamins René , Kitakura Saeko , Sigmund Harald F. , Jun Kim S. , Hauser Marie‐Theres , Friml Jiří , Luschnig Christian 
Published: July 2007

SummaryPolar transport of the phytohormone auxin controls numerous growth responses in plants. Molecular characterization of auxin transport in Arabidopsis thaliana has provided important insights into the mechanisms underlying the regulation of auxin distribution. In particular, the control of subcellular localization and expression of PIN‐type auxin efflux components appears to be fundamental for orchestrated distribution of the growth regulator throughout the entire plant body. Here we describe the identification of two Arabidopsis loci, MOP2 and MOP3 (for MODULATOR OF PIN), that are involved in control of the steady‐state levels of PIN protein. Mutations in both loci result in defects in auxin distribution and polar auxin transport, and cause phenotypes consistent with a reduction of PIN protein levels. Genetic interaction between PIN2 and both MOP loci is suggestive of functional cross‐talk, which is further substantiated by findings demonstrating that ectopic PIN up‐regulation is compensated in the mop background. Thus, in addition to pathways that control PIN localization and transcription, MOP2 and MOP3 appear to be involved in fine‐tuning of auxin distribution via post‐transcriptional regulation of PIN expression.
A mitochondrial protein homologous to the mammalian peripheral‐type benzodiazepine receptor is essential for stress adaptation in plants
Authors: Frank Wolfgang , Baar Kim‐Miriam , Qudeimat Enas , Woriedh Mayada , Alawady Ali , Ratnadewi Diah , Gremillon Louis , Grimm Bernhard , Reski Ralf 
Published: July 2007

SummaryThe cloning of abiotic stress‐inducible genes from the moss Physcomitrella patens led to the identification of the gene PpTSPO1, encoding a protein homologous to the mammalian mitochondrial peripheral‐type benzodiazepine receptor and the bacterial tryptophane‐rich sensory protein. This class of proteins is involved in the transport of intermediates of the tetrapyrrole biosynthesis pathway. Like the mammalian homologue, the PpTSPO1 protein is localized to mitochondria. The generation of PpTSPO1‐targeted moss knock‐out lines revealed an essential function of the gene in abiotic stress adaptation. Under stress conditions, the PpTSPO1 null mutants show elevated H2O2 levels, enhanced lipid peroxidation and cell death, indicating an important role of PpTSPO1 in redox homeostasis. We hypothesize that PpTSPO1 acts to direct porphyrin precursors to the mitochondria for heme formation, and is involved in the removal of photoreactive tetrapyrrole intermediates.
Characterization of Arabidopsis thaliana mismatch specific endonucleases: application to mutation discovery by TILLING in pea
Authors: Triques Karine , Sturbois Bénédicte , Gallais Stéphane , Dalmais Marion , Chauvin Stéphanie , Clepet Christian , Aubourg Sébastien , Rameau Catherine , Caboche Michel , Bendahmane Abdelhafid 
Published: July 2007

SummaryScanning DNA sequences for mutations and polymorphisms has become one of the most challenging, often expensive and time‐consuming obstacles in many molecular genetic applications, including reverse genetic and clinical diagnostic applications. Enzymatic mutation detection methods are based on the cleavage of heteroduplex DNA at the mismatch sites. These methods are often limited by the availability of a mismatch‐specific endonuclease, their sensitivity in detecting one allele in a pool of DNA and their costs. Here, we present detailed biochemical analysis of five Arabidopsis putative mismatch‐specific endonucleases. One of them, ENDO1, is presented as the first endonuclease that recognizes and cleaves all types of mismatches with high efficiency. We report on a very simple protocol for the expression and purification of ENDO1. The ENDO1 system could be exploited in a wide range of mutation diagnostic tools. In particular, we report the use of ENDO1 for discovery of point mutations in the gibberellin 3β‐hydrolase gene of Pisum sativum. Twenty‐one independent mutants were isolated, five of these were characterized and two new mutations affecting internodes length were identified. To further evaluate the quality of the mutant population we screened for mutations in four other genes and identified 5–21 new alleles per target. Based on the frequency of the obtained alleles we concluded that the pea population described here would be suitable for use in a large reverse‐genetics project.
Characterization of seed‐specific benzoyloxyglucosinolate mutations in Arabidopsis thaliana
Authors: Kliebenstein Daniel J. , D’Auria John C. , Behere Aditi S. , Kim Jae Hak , Gunderson Kevin L. , Breen John N. , Lee Grace , Gershenzon Jonathan , Last Robert L. , Jander Georg 
Published: July 2007

SummaryGlucosinolates are secondary metabolites involved in pathogen and insect defense of cruciferous plants. Although seeds and vegetative tissue often have very different glucosinolate profiles, few genetic factors that determine seed glucosinolate accumulation have been identified. An HPLC‐based screen of 5500 mutagenized Arabidopsis thaliana lines produced 33 glucosinolate mutants, of which 21 have seed‐specific changes. Five of these mutant lines, representing three genetic loci, are compromised in the biosynthesis of benzoyloxyglucosinolates, which are only found in seeds and young seedlings of A. thaliana. Genetic mapping and analysis of T‐DNA insertions in candidate genes identified BZO1 (At1g65880), which encodes an enzyme with benzoyl‐CoA ligase activity, as being required for the accumulation of benzoyloxyglucosinolates. Long‐chain aliphatic glucosinolates are elevated in bzo1 mutants, suggesting substrate competition for the common short‐chain aliphatic glucosinolate precursors. Whereas bzo1 mutations have seed‐specific effects on benzoyloxyglucosinolate accumulation, the relative abundance of 3‐benzoyloxypropyl‐ and 4‐benzoyloxybutylglucosinolates depends on the maternal genotype.
The plastid sigma factor SIG1 maintains photosystem I activity via regulated expression of the psaA operon in rice chloroplasts
Authors: Tozawa Yuzuru , Teraishi Masayoshi , Sasaki Tadamasa , Sonoike Kintake , Nishiyama Yoshitaka , Itaya Mitsuhiro , Miyao Akio , Hirochika Hirohiko 
Published: July 2007

SummarySigma factors encoded by the nucleus of plants confer promoter specificity on the bacterial‐type RNA polymerase in chloroplasts. We previously showed that transcripts of OsSIG1, which encodes one such sigma factor in rice, accumulate relatively late during leaf development. We have now isolated and characterized two allelic mutants of OsSIG1, in which OsSIG1 is disrupted by insertion of the retrotransposon Tos17, in order to characterize the functions of OsSIG1. The OsSIG1−/− plants were found to be fertile but they manifested an approximately one‐third reduction in the chlorophyll content of mature leaves. Quantitative RT‐PCR and northern blot analyses of chloroplast gene expression revealed that the abundance of transcripts derived from the psaA operon was markedly reduced in OsSIG1−/− plants compared with that in wild‐type homozygotes. This effect was accompanied by a reduction in the abundance of the core protein complex (PsaA–PsaB) of photosystem I. Analysis of chlorophyll fluorescence also revealed a substantial reduction in the rate of electron transfer from photosystem II to photosystem I in the OsSIG1 mutants. Our results thus indicate that OsSIG1 plays an important role in the maintenance of photosynthetic activity in mature chloroplasts of rice by regulating expression of chloroplast genes for components of photosystem I.