bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular changes in organic matter of a compost‐amended soil
Authors: Spaccini R. , Sannino D. , Piccolo A. , Fagnano M. 
Published: February 2009

SummaryThe molecular changes of organic matter in a cultivated soil after compost amendments was followed by off‐line‐pyrolysis‐TMAH GC‐MS. Thermochemolysis of soil and compost provided a detailed molecular characterization of soil organic matter (SOM) by releasing a large amount of different molecules mainly derived from plant biopolymers such as lignin, waxes and bio‐polyesters. No significant differences were found before and after 1 year of cultivation in the pyrolytic products released by control soil, which were mainly fatty acids, oxidized forms of lignins, and minor amounts of microbial bio‐products and biopolyesters derivatives. Conversely, significant qualitative and quantitative variations were found in the molecular characteristics of SOM between control and compost‐amended soils after 1 year of cultivation. Increasing amounts and diversified components of fatty acids, n‐alkanes and various biopolyesters derivatives such as hydroxy‐alkanoic and alkandioic acids were found in the compost‐amended soil. These results indicate that a significant amount of exogenous compost‐derived organic molecules were incorporated into SOM after 1 year of cultivation. The organic structural indexes derived from these results indicated direct inputs of undecomposed lignin residues and hydrocarbon waxes from compost material. When compared with the control soil, small but significant amounts of plant biomarkers, such as cyclic di‐ and triterpenes derivatives, were found only in the compost‐amended soil. These findings suggest that the molecular changes of SOM brought about by amendment with biomass residues can be followed by using thermochemolysis of bulk soil samples.
Expression of embryonic stem cell markers in cultured JKT‐1, a cell line derived from a human seminoma
Authors: Bouskine Adil , Vega Aurélie , Nebout Marielle , Benahmed Mohamed , Fénichel Patrick 
Published: February 2009

SummaryTesticular germ cell tumours (TGCTs), the most frequent solid tumour of the young men, originate from the primitive germ cells. They share some pluripotency stem‐cell markers which may help to distinguish between seminoma, the most frequent TGCTs and non‐seminoma tumours, such as embryonal carcinoma, teratocarcinoma or choriocarcinoma. Due probably to the propensity of seminoma to apoptosis, only two cell lines originated from pure testicular seminoma, TCam‐2 and JKT‐1 have been up to now, established, maintained and proposed as representative models of human testicular seminoma. However, both seem, following recent reports, to be able to drift. Thus, the molecular signature of embryonic stem‐cell markers of the JKT‐1 cells cultured in our laboratory, were studied by RT‐PCR, Western blot and immunofluorescence (IF). JKT‐1 cells analysed after 30 passages, expressed placenta alkaline phosphatase but not alphafoetoprotein (αFP) nor beta‐human chorionic gonadotropin. JKT‐1 cells also expressed markers of pluripotency such as NANOG and OCT3/4 and more specific seminoma markers, such as AP2γ and HIWI. However, protein expression of OCT3/4 and AP2y was weak and these JKT‐1 cells expressed SOX2, a marker of embryonal carcinoma and did not express c‐KIT usually expressed in most seminoma. Possible derivation through in vitro culture conditions was supported by looking at later passages (61) which showed a decrease of NANOG and HIWI protein expression. JKT‐1 cells express a signature of markers which is still near from the one express by seminoma cells, allowing carcinogenetic studies. However, because of their great ability to drift as shown for TCam‐2, it is recommended to verify and to precise this molecular signature before reporting functional results.
The age‐related decline of testosterone is associated with different specific symptoms and signs in patients with sexual dysfunction
Authors: Corona G. , Mannucci E. , Ricca V. , Lotti F. , Boddi V. , Bandini E. , Balercia G. , Forti G. , Maggi M. 
Published: February 2009

SummaryIn males, testosterone (T) levels decline with ageing. Several symptoms characteristic of the ageing process are similar to those related to hypogonadism. The aim of the present study was to evaluate the specific association among hypogonadism‐related symptoms and signs and the ageing process. A consecutive series of 1647 (mean age 52.4 ± 13.1 years) male patients with sexual dysfunction were investigated. Several hormonal and biochemical, instrumental and psychological parameters were studied. The parameters significantly associated with total levels in the entire cohort, after adjustment for confounders, were studied as a function of age and T quartiles. In all age quartiles, low T was associated with higher waist circumference and triglyceride levels and with an increased prevalence of metabolic syndrome. The prevalence of hypoactive sexual desire decreased as a function of T only in the youngest (17‐ to 42‐year old) age quartile as well as the reported reduction in nocturnal erections. In the oldest age quartile, we found an inverse relationship between T levels and the prevalence of severe erectile dysfunction and a positive relationship with intercourse frequency. Accordingly, in the oldest age quartile, subjects with higher T levels showed better penile flow at penile colour doppler ultrasound as well as a better lipid profile. Finally, an inverse association between somatized anxiety and T levels was observed only in the oldest age quartile. In conclusion, our study shows for the first time that in subjects with sexual dysfunction, some hypogonadism‐related symptoms can be age‐specific. In particular, low T is associated with sexual dysfunction more often in the oldest subjects.
Hepatic steatosis is associated with low serum testosterone and high serum DHEAS levels in men
Authors: Völzke Henry , Aumann Nicole , Krebs Alexander , Nauck Matthias , Steveling Antje , Lerch Markus M. , Rosskopf Dieter , Wallaschofski Henri 
Published: February 2009

SummaryObesity and metabolic syndrome are associated with low serum testosterone levels. Hepatic steatosis contributes to the metabolic syndrome and might be regarded as its hepatic manifestation. In this study, we sought to investigate the relationship between hepatic steatosis, serum testosterone and dehydroepiandrosterone sulphate (DHEAS) levels in men. This is a cross‐sectional population‐based study. We used data of 1912 men recruited for the population‐based Study of Health in Pomerania, which was conducted in a region with high prevalence of metabolic syndrome and related diseases. Hepatic steatosis was defined according to sonographic criteria. The relationship of hepatic steatosis with serum testosterone and DHEAS levels was analysed by multivariable logistic regression. Men with low serum testosterone levels had a higher risk of hepatic steatosis than men with high serum testosterone levels. Adjustment for age and further confounders attenuated this association, but did not affect statistical significance (odds ratio 2.36; 95% confidence interval 1.66–3.37; p < 0.05). In the full model, the highest risk of hepatic steatosis was found in subjects with the highest serum DHEAS levels (odds ratio 1.59; 95% confidence interval 1.04–2.43; p < 0.05). Exclusion of men with high alcohol consumption did not affect these results substantially. Hepatic steatosis is associated with low serum testosterone and high serum DHEAS levels. These associations are independent of alcohol consumption.
Microsatellite variability reveals the necessity for genetic input from wild giant pandas (Ailuropoda melanoleuca) into the captive population
Authors: SHEN FUJUN , ZHANG ZHIHE , HE WEI. , YUE BISONG , ZHANG ANJU. , ZHANG LIANG , HOU RONG. , WANG CHENGDONG , WATANABE TOSHI 
Published: February 2009

AbstractRecent success in breeding giant pandas in captivity has encouraged panda conservationists to believe that the ex situ population is ready to serve as a source for supporting the wild population. In this study, we used 11 microsatellite DNA markers to assess the amount and distribution of genetic variability present in the two largest captive populations (Chengdu Research Base of Giant Panda Breeding, Sichuan Province and the China Research and Conservation Center for the Giant Panda at Wolong, Sichuan Province). The data were compared with those samples from wild pandas living in two key giant panda nature reserves (Baoxing Nature Reserve and Wanglang Nature Reserve). The results show that the captive populations have retained lower levels of allelic diversity and heterozygosity compared to isolated wild populations. However, low inbreeding coefficients indicate that captive populations are under careful genetic management. Excessive heterozygosity suggests that the two captive populations have experienced a genetic bottleneck, presumably caused by founder effects. Moreover, evidence of increased genetic divergence demonstrates restricted breeding options within facilities. Based on these results, we conclude that the genetic diversity in the captive populations is not optimal. Introduction of genetic materials from wild pandas and improved exchange of genetic materials among institutions will be necessary for the captive pandas to be representative of the wild populations.
Conservation of the introgressed European water frog complex using molecular tools
Authors: HOLSBEEK G. , MAES G. E. , DE MEESTER L. , VOLCKAERT F. A. M. 
Published: February 2009

AbstractIn Belgium, the Pelophylax esculentus complex has recently been subjected to multiple introductions of non‐native water frogs, increasing the occurrence of hybridisation events. In the present study, we tested the reliability of morphometric and recently developed microsatellite tools to identify introgression and to determine the origin of exotic Belgian water frogs. By analysing 150 individuals of each taxon of the P. esculentus complex and an additional 60 specimens of the introduced P. cf. bedriagae, we show that neither of the currently available tools appears to have sufficient power to reliably distinguish all Belgian water frog species. We therefore aimed at increasing the discriminatory power of a microsatellite identification tool by developing a new marker panel with additional microsatellite loci. By adding only two new microsatellite loci (RlCA5 and RlCA1b20), all taxa of the P. esculentus complex could be distinguished from each other with high confidence. Three more loci (Res3, Res5 and Res17) provided a powerful discrimination of the exotic species.
Ancient isolation and independent evolution of the three clonal lineages of the exotic sudden oak death pathogen Phytophthora ramorum
Authors: GOSS E. M. , CARBONE I. , GRÜNWALD N. J. 
Published: February 2009

AbstractThe genus Phytophthora includes some of the most destructive plant pathogens affecting agricultural and native ecosystems and is responsible for a number of recent emerging and re‐emerging infectious diseases of plants. Sudden oak death, caused by the exotic pathogen P. ramorum, has caused extensive mortality of oaks and tanoaks in Northern California, and has brought economic losses to US and European nurseries as well due to its infection of common ornamental plants. In its known range, P. ramorum occurs as three distinct clonal lineages. We inferred the evolutionary history of P. ramorum from nuclear sequence data using coalescent‐based approaches. We found that the three lineages have been diverging for at least 11% of their history, an evolutionarily significant amount of time estimated to be on the order of 165 000 to 500 000 years. There was also strong evidence for historical recombination between the lineages, indicating that the ancestors of the P. ramorum lineages were members of a sexually reproducing population. Due to this recombination, the ages of the lineages varied within and between loci, but coalescent analyses suggested that the European lineage may be older than the North American lineages. The divergence of the three clonal lineages of P. ramorum supports a scenario in which the three lineages originated from different geographic locations that were sufficiently isolated from each other to allow independent evolution prior to introduction to North America and Europe. It is thus probable that the emergence of P. ramorum in North America and Europe was the result of three independent migration events.
Multiple gene genealogies reveal asymmetrical hybridization and introgression among strongylocentrotid sea urchins
Authors: ADDISON JASON A. , POGSON GRANT H. 
Published: February 2009

AbstractThe evolution of incompatibilities between eggs and sperm is thought to play important roles in establishing and maintaining reproductive isolation among species of broadcast‐spawning marine invertebrates. However, the effectiveness of gametic isolation in initiating the speciation process and/or in limiting the introgression of genes among species at later stages of divergence remains largely unknown. In the present study, we collected DNA sequence data from five loci in four species ofStrongylocentrotussea urchins (S. droebachiensis,S. pallidus,S. purpuratus, andS. franciscanus) to test whether the susceptibility ofS. droebachiensiseggs to fertilization by heterospecific sperm results in gene flow between species. Despite the potential for introgression, a small but statistically significant signal of introgression was observed only between the youngest pair of sister taxa (S. pallidusandS. droebachiensis) that was strongly asymmetrical (from the former into the latter). No significant gene flow was observed for eitherS. purpuratusorS. franciscanusdespite the ability of their sperm to readily fertilize the eggs ofS. droebachiensis. Our results demonstrate that asymmetrical gamete compatibilities in strongylocentrotids can give rise to asymmetrical patterns of introgression but suggest that gamete traits alone cannot be responsible for maintaining species integrities. The genetic boundaries between strongylocentrotid urchin species in the northeast Pacific appear to be related to postzygotic isolating mechanisms that scale with divergence times and not intrinsic gametic incompatibilitiesper se.
Evidence of parasite‐mediated disruptive selection on genetic diversity in a wild fish population
Authors: BLANCHET SIMON , REY OLIVIER , BERTHIER PAULINE , LEK SOVAN , LOOT GERALDINE 
Published: February 2009

AbstractIdentifying the processes maintaining genetic variability in wild populations is a major concern in conservation and evolutionary biology. Parasite‐mediated selection may strongly affect genetic variability in wild populations. The inbreeding depression theory predicts that directional selection imposed by parasites should act against the most inbred hosts, thus favouring genetic diversity in wild populations. We have tested this prediction by evaluating the strength and shape of the relationship between the load of a harmful fin‐feeder ectoparasite (Tracheliastes polycolpus) and the genome‐wide genetic diversity (i.e. heterozygosity measured at a set of 15 microsatellites) of its fish host, the rostrum dace (Leuciscus leuciscus). Contrary to expectation, we found a nonlinear relationship between host genetic diversity and ectoparasite load, with hosts that were either homozygous or heterozygous harbouring significantly fewer parasites than hosts with an intermediate level of heterozygosity. This relationship suggests that parasites could increase the variance of global heterozygosity in this host population through disruptive selection on genetic diversity. Moreover, when genetic diversity was measured at each locus separately, we found two very strong positive associations between host genetic diversity and the ectoparasite load. This latter result has three main implications: (i) genome‐wide effect cannot alone explain the nonlinear relationship between global heterozygosity and ectoparasite load, (ii) negative non‐additive allelic interactions (i.e. underdominance) may be a mechanism for resisting ectoparasite infection, and (iii) ectoparasites may favour homozygosity at some loci in this host population.
Two small c‐type cytochromes affect virulence gene expression in Bacillus anthracis
Authors: Wilson Adam C. , Hoch James A. , Perego Marta 
Published: February 2009

SummaryRegulated expression of the genes for anthrax toxin proteins is essential for the virulence of the pathogenic bacterium Bacillus anthracis. Induction of toxin gene expression depends on several factors, including temperature, bicarbonate levels, and metabolic state of the cell. To identify factors that regulate toxin expression, transposon mutagenesis was performed under non‐inducing conditions and mutants were isolated that untimely expressed high levels of toxin. A number of these mutations clustered in the haem biosynthetic and cytochrome c maturation pathways. Genetic analysis revealed that two haem‐dependent, small c‐type cytochromes, CccA and CccB, located on the extracellular surface of the cytoplasmic membrane, regulate toxin gene expression by affecting the expression of the master virulence regulator AtxA. Deregulated AtxA expression in early exponential phase resulted in increased expression of toxin genes in response to loss of the CccA‐CccB signalling pathway. This is the first function identified for these two small c‐type cytochromes of Bacillus species. Extension of the transposon screen identified a previously uncharacterized protein, BAS3568, highly conserved across many bacterial and archeal species, as involved in cytochrome c activity and virulence regulation. These findings are significant not only to virulence regulation in B. anthracis, but also to analysis of virulence regulation in many pathogenic bacteria and to the study of cytochrome c activity in Gram‐positive bacteria.
Lower‐crust S‐wave velocity beneath western Yunnan Province from waveform inversion of dense seismic observations
Authors: Gao Xing , Su Youliang , Wang Weimin , Pei Shunping , Guo Zhi 
Published: February 2009

AbstractWe use teleseismic body waveforms to explore S‐wave layered velocity structures beneath 30 portable digital seismic stations deployed around western Yunnan Province. Results show that the Moho depth in this region is ∼40 km and decreases in general from north to south, consistent with previous geophysical studies. Associated with this lateral variation of the Moho depth, the lower crust above the Moho discontinuity has a 15–25 km thick zone with an S‐wave velocity lower than that of the upper crust. This lower velocity zone might be interpreted as a lower crust weak channel, which may mechanically partially decouple the upper‐crust deformation from the underlying mantle. Thus, the inverted S‐wave velocity structure could provide new evidence for the lateral flow of lower crust in the build‐up of the south‐eastern Tibetan plateau.
Assessing the marginal error in diagnosis and cure of Schistosoma mansoni in areas of low endemicity using Percoll and PCR techniques
Authors: Allam Amal Farahat , Kader Ola , Zaki Adel , Youssef Shehab Amel , Farag Hoda Fahmy 
Published: February 2009

SummaryObjective  The Kato–Katz technique misses a proportion of low‐intensity schistosomiasis cases. We set out to estimate the rate of false negative results after Kato–Katz.Method  Comparison with the more sensitive Percoll technique and polymerase chain reaction (PCR).Results  Amongst Kato–Katz negative Schistosoma mansoni specimens in a hypoendemic area, Percoll detected 11% positive cases and PCR detected 23%. After treatment, the cure rate was 97% by Kato–Katz, 90% by Percoll and 71% by PCR. Results of Kato–Katz and Percoll showed moderate agreement, all cases positive by Kato–Katz were positive by Percoll. However, PCR showed some negative results amongst cases considered sure positives.Conclusion  The Percoll technique seems to be the technique of choice for diagnosis of S. mansoni in low intensity areas and after treatment.
Domestic smoke exposure is associated with alveolar macrophage particulate load
Authors: Fullerton Duncan G. , Jere Khuzwayo , Jambo Kondwani , Kulkarni Neeta S. , Zijlstra Eduard E. , Grigg Jonathan , French Neil , Molyneux Malcolm E. , Gordon Stephen B. 
Published: February 2009

SummaryObjectives  Indoor air pollution is associated with impaired respiratory health. The pre‐dominant indoor air pollutant to which two billion of the world’s population is exposed is biomass fuel smoke. We tested the hypothesis that reported smoke exposure in men and women is associated with increased alveolar macrophage uptake of biomass smoke particulates.Methods  Healthy volunteers attending for research bronchoscopy in Malawi completed a questionnaire assessment of smoke exposure. Particulate matter visible in alveolar macrophages (AM) was quantified using digital image analysis. The geometric mean of the percentage area of the cytoplasm occupied by particulates in 50 cover‐slip adherent AM was calculated and termed particulate load.Results  In 57 subjects (40 men and 17 women) there was a significant difference between the particulate load in groups divided according to pre‐dominant lighting form used at home (anovaP = 0.0009) and type of cooking fuel (P = 0.0078).Conclusions  Particulate load observed in macrophages is associated with the reported type of biomass fuel exposure. Macrophage function in relation to respiratory health should now be investigated in biomass smoke exposed subjects.
Impact of intense, longitudinal retreatment with praziquantel on cure rates of schistosomiasis mansoni in a cohort of occupationally exposed adults in western Kenya
Authors: Black Carla L. , Steinauer Michelle L. , Mwinzi Pauline N. M. , Evan Secor W. , Karanja Diana M. S. , Colley Daniel G. 
Published: February 2009

SummaryObjective  To investigate trends in the efficacy of praziquantel (PZQ) suggestive of the emergence of drug resistance against Schistosoma mansoni infection after 12.5 years of intense, repeated use in a small geographic area along the shores of Lake Victoria.Methods  As part of a longitudinal study, 178 men occupationally exposed to schistosomes were repeatedly tested for S. mansoni infection at 4‐ to 6‐week intervals and treated with PZQ at each reinfection. We compared cure rates by year of study and examined factors associated with cure failure in a multivariate logistic regression model.Results  Overall, the cure rate after a single dose of PZQ was 66%, ranging annually from 36% to 82%. In multivariate analysis, failure to cure after 1 PZQ dose was significantly associated with high intensity of infection and having fewer previous exposures to dying worms. Even after adjustment for these factors, treatments administered in 2006 were significantly more likely to result in cure failures than treatments administered in 2004, the year in which PZQ efficacy was highest. While cure rates varied over the course of 12 years, there was no consistent downward trend towards decreased efficacy over time. In years for which malacological data were available, periods of low PZQ efficacy coincide with high rates of S. mansoni infection in nearby snail populations.Conclusion  We did not find a pattern of cure failures consistent with development of clinical resistance to PZQ in our intensely treated cohort.
PCR diagnosis of visceral leishmaniasis in an endemic region, Mymensingh district, Bangladesh
Authors: Alam Mohammad Zahangir , Shamsuzzaman Abul Khair M. , Kuhls Katrin , Schönian Gabriele 
Published: February 2009

SummaryDetection of Leishmania parasites in a clinical sample is necessary to confirm a suspected case of leishmaniasis. We compared the sensitivity of internal transcribed spacer 1‐PCR (ITS 1‐PCR) assay for parasite diagnosis with that of microscopic detection in clinical samples from kala‐azar (KA) or post‐kala‐azar dermal leishmaniasis (PKDL) suspects in Mymensingh. Of 39 specimens collected from 35 KA and four PKDL suspects, 26 were positive by microscopic examination of smears from bone marrow and skin exudates; 38 specimens spotted on filter paper and 27 of the 28 Giemsa‐stained slides tested by PCR proved positive by ITS1‐PCR.