bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, electrical and photoresponse properties of vertically well-aligned and epitaxial ZnO nanorods on GaN-buffered sapphire substrates
Authors: Park Jae Young , Yun Young Su , Hong Yong Sung , Oh Hwangyou , Kim Ju-Jin , Kim Sang Sub
Published: September 2005

Vertically well-aligned and epitaxial ZnO nanorod arrays (NRAs) were synthesized by catalyst-free metalorganic chemical vapor deposition on Al2O3 (0001) substrates particularly using an epitaxially grown GaN buffer layer. ZnO NRAs grown directly on Al2O3 (0001) substrates are aligned vertically, but randomly oriented in the lateral direction to the substrates. In sharp contrast, ZnO NRAs grown with a GaN buffer layer show an excellent vertical and epitaxial alignment with mosaic distributions of 0.11° and 1.28° in the out-of- and the in-plane directions, respectively. The electrical measurements using field effect transistors based on individual ZnO nanorods show a pronounced n-type gate modulation with an electron concentration of ∼7.5×1017cm−3 and an electron mobility of ∼25.1cm2∕Vs at a bias voltage of 1 V, while showing quite a high on/off ratio exceeding ∼105. In addition, their high on/off conductivity ratio of ∼103 with UV light gives a potential of their use in nanoscale UV detectors.
Transformation of potato using an antisense class I patatin gene and its effect on microtuber formation
Authors: Huai-Jun Si , Jun Liu , Cong-Hua Xie
Published: September 2005

An antisense class I patatin gene under control of the CaMV 35S promoter was introduced into potato (Solanum tuberosum) cultivar E-potato 3 using the Agrobacterium tumefaciens system. PCR amplification and PCR–Southern blot analysis indicated that the antisense class I patatin gene had been integrated into the potato genome. Northern hybridization analysis showed that the antisense gene transcribed normally in the transgenic potato plants and resulted in a reduction of endogenous class I patatin mRNA. Total soluble protein content and lipid acyl hydrolase activity of microtubers, derived from transformed plants, decreased by a maximum of 36.4% and 31.4%, respectively, compared with control plants. The expression of this antisense gene also resulted in reductions of the plantlets forming tubers, tubers per plantlet and the effective tubers (≥50 mg) of the transformed plants.
Assessment ofMagnaporthe griseamating type by PCR
Authors: Bao-Hua Wang , Guo-Dong Lu , Hai-Ming Li , Yan Lin , Zong-Hua Wang
Published: September 2005

Analysis of mating type can provide an evaluation of the population genetic diversity of the rice blast fungus,Magnaporthe grisea. According to the sequences ofMAT1-1andMAT1-2genes of the fungus, two pairs of PCR primers specific to theMAT1-1andMAT1-2alleles were designed, and the PCR thermal profile was also optimized. To confirm its application in mating type assessment, 10 tester isolates were tested by PCR. The PCR amplification pattern of these tester isolates corresponded to their known mating type. Furthermore, 150 rice-field isolates from Fujian Province were mated with tester isolates GUY11 and KA3 side by side and also tested by PCR. Results showed that 95.1% of 123 fertile isolates were the same in mating type as determined by both PCR-amplified allele-specific fragments and mating with GUY11/KA3. Among 27 sterile isolates determined by GUY11 and KA3, seven wereMAT1-1and 20 wereMAT1-2as determined by PCR. This study indicates that PCR is applicable in assessingM. griseamating type and especially is capable of predicting the potential mating type of sterile isolates in the natural population of the fungus.
Simultaneous detection of bovine- and sheep-derived materials in feedstuffs by PCR
Authors: Wei-Gang Wen , Xiu-Ling Zhao , Shui-Shan He , Hua-Hong Du , Shao-Tang Huang
Published: September 2005

To control the spread of bovine spongiform encephalopathy and scrapie, a method was developed for the simultaneous detection of bovine- and sheep-derived materials in feedstuffs. Chelex-100 was adopted for the fast extraction of animal genomic DNA. A pair of universal primers, designed on the basis of homology in sequences of bovine and sheep mtDNA, was used for PCR. This method is of great value to quarantine departments for its simplicity and rapid detection.
Cloning and nucleotide sequence of the cDNA encoding a β-1,3-glucanase-like protein secreted from growing pollen tubes of Japanese pear (Pyrus pyrifolia)
Authors: Yue-Gang Zhou , Norioka Naoko , Shao-Liang Li , Norioka Shigemi
Published: September 2005

A pollen cDNA library of Japanese pear (Pyrus pyrifolia) from the family Rosaceae was constructed and a cDNA (bgn-1) of 1408 bp, which encodes a protein (BGN-1) secreted from growing pollen tubes, was cloned and sequenced. bgn-1 cDNA is composed of a 5′-untranslated region of 47 bp, an open reading frame of 1194 bp encoding 397 amino acid residues and a complete 3′-untranslated region of 167 bp. Alignment of the deduced amino acid sequence of bgn-1 with that of barley (Hordeum vulgare) β-1,3-glucanase (GII) showed 39.7% amino acid identity. Several residues that were critical for the function of GII were conserved in the deduced BGN-1 polypeptide. Moreover, hydrophobic cluster analysis (HCA) showed an overall HCA homology score of 87.1% and analysis of BGN-1 with the 3D-PSSM program predicted a three-dimensional structure of BGN-1 highly homologous to that of barley GII with ≥95% certainty. These results suggest that the cloned bgn-1 cDNA encodes a β-1,3-glucanase-like protein in Japanese pear. The predicted mature protein (375 amino acids) has a theoretical molecular mass of 40 723 Da, a basic pI of 9.59 and a diagnostic amino acid residue mode of D, L, S and L, which is very similar to that of growth-related subfamily D (D, L, S and Q) in cereals. A ProXXPro repeat is also found between positions 352 and 367 in the C-extension region.
Characterization of trait variations in progenies of Gossypium hirsutum transformed with the genomic DNA of Gossypium barbadense
Authors: Xiong-Ming Du , Zhao-E Pan , Jun-Ling Sun , Zhong-Li Zhou , Bao-Yin Pang
Published: September 2005

Four variant lines, HB1, HB2, HB3 and HB4, were derived from progenies of upland cotton (Gossypium hirsutum) cultivar Yumian 17 that had been transformed with genomic DNA from sea island cotton, Gossypium barbadense, using the pollen tube pathway (PTP) method. They showed significant differences from the wild-type recipient in terms of fibre quality, lint percentage, boll weight and other agronomic traits. The four variant lines also differed from the wild-type recipient in the amplification products of two SSR loci, indicating that the DNA of G. barbadense had been introduced into the genome of the recipient and was inherited stably. On the other hand, the agronomic traits of another three lines (HB5, HB6 and HB7) derived from the same transformation experiment were identical to those of the wild-type recipient, indicating that G. barbadense DNA had not integrated into the genome of these lines. A combination of the analyses on agronomic traits and SSR markers indicated that transgenic upland cotton strains produced by the PTP method could become homozygous in only a few generations and the foreign DNA introduced during the transformation experiments could be inherited stably in the transgenic progenies.
Improving biocontrol effect ofPseudomonas fluorescensP5 on plant diseases by genetic modification with chitinase gene
Authors: Xiao-Jing Xu , Li-Qun Zhang , You-Yong Zhu , Wen-Hua Tang
Published: September 2005

Pseudomonas fluorescensP5 was isolated in Yunnan Province and proved to be an effective biocontrol agent of various soil-borne plant diseases. The aim of the study was to enhance the biocontrol effect of this strain by introducing a chitinase gene. A 6.5 kb DNA fragment containing the chitinase genechiBwas inserted into pDSK519 vector to construct a new plasmid, pDSK51965. This plasmid was introduced intoP. fluorescensP5 and resulted in a new strain named P5-1. Restriction enzyme digestion and chitin plate culture confirmed that P5-1 contained a functional chitinase gene. Compared with wild-type P5 in pot experiments, P5-1 had an increased effect against rice sheath blight and cotton damping-off caused byRhizoctonia solani. It also increased the effect on suppression of wheat take-all caused byGaeumannomyces graminisvar.tritici.
Triclabendazole: new skills to unravel an old(ish) enigma
Authors: Fairweather I.
Published: September 2005

Triclabendazole was introduced in the early 1980s for the treatment of Fasciola hepatica infections in livestock. Due to its high activity against immature flukes, it has become established as the principal anti-fluke drug on the market. More recently, triclabendazole has been used to treat human cases of fascioliasis and is now the drug of choice for this infection, too. Resistance to triclabendazole was first reported in 1995 in a field population in Australia and, since that time, resistant populations have been identified in several countries in Europe. Parallel to the spread of resistance has been a sharp increase in the prevalence of fascioliasis, which has been attributed largely to climate changes. Consequently, farmers are faced with an alarming scenario, as none of the other fasciolicides on the market possess such high activity against the damaging immature stages of fluke. The main aim of this review is to assess current understanding of the mechanism of action of triclabendazole against the fluke and the mechanism by which the fluke has become resistant to it. The use of triclabendazole against animal and human infections is summarized and suggestions are given on ways to deal with resistance. Gaps in the knowledge of various aspects of its use are highlighted and this may serve to open up future research areas.
Fas2-ELISA in the detection of human infection by Fasciola hepatica
Authors: Espinoza J.R. , Timoteo O. , Herrera-Velit P.
Published: September 2005

Fasciola hepatica has recently emerged as a major pathogen of humans from reports on areas of endemicity and hyper-endemicity for fascioliasis. This situation is aggravated by the lack of standard assays for the screen diagnosis of F. hepatica infection in humans living in endemic areas. Our laboratory has developed an enzyme-linked immunosorbent assay (Fas2-ELISA) based on the capture of IgG antibody by a purified protein Fas2, which is an adult fluke cysteine proteinase. Fas2-ELISA exhibited 95% sensitivity and 100% specificity in 38 individuals infected with F. hepatica diagnosed by finding eggs in stools and 46 serum samples from healthy volunteers. No cross-reaction was observed with 54 serum samples from patients with ten different parasitic infections including the trematodes Paragonimus westermani and Schistosoma mansoni. The high antigenicity of Fas2 is suggested by the fact that antibodies to Fas2 rise rapidly by 1–2 weeks of infection and rise until patency at 8 weeks of infection in experimentally infected alpacas. Field screening for human fascioliasis using Fas2-ELISA and coprology in three endemic locations of the Peruvian Andes resulted in 95.5% sensitivity, 86.6% specificity in a population of 664 children in an age range of 1 to 16 years old. These results provide evidence of the clinical potential of Fas2-ELISA to diagnose fascioliasis in humans exposed to liver fluke infection in endemic areas for this parasite. Fas2-ELISA is currently developed as a standard assay for both field screening for fascioliasis in people living in endemic areas and detecting occasionally F. hepatica infected patients in clinical laboratories.
Fasciola antigens as vaccines against fascioliasis and schistosomiasis
Authors: Hillyer G.V.
Published: September 2005

Fascioliasis is an important trematode infection of herbivores worldwide with increasing evidence of prevalence as a disease of humans. Vaccination studies with purified native and recombinant Fasciola antigens suggest that this approach to diminished morbidity and mortality and reduced transmission is a realistic goal. Among the major potential vaccine candidates are fatty acid binding protein (FABP), cysteine (cathepsin) proteases, haemoglobulin, leucine aminopeptidase, and a saposin-like protein. In the case of Fasciola hepatica FABP, cross-reaction and cross-protection against Schistosoma mansoni is an important feature. In addition to protective effects with significant worm burden reductions, some vaccine candidates also have anti-fecundity (smaller flukes), anti-pathology (less liver lesions), and anti-embryonation effects. Optimism is tempered by the fact that fascioliasis in humans is an orphan disease and in need of governmental and foundation support.
Urinary schistosomiasis on Zanzibar: application of two novel assays for the detection of excreted albumin and haemoglobin in urine
Authors: Rollinson D. , Klinger E.V. , Mgeni A.F. , Khamis I.S. , Stothard J.R.
Published: September 2005

As part of a urinary schistosomiasis control programme on Zanzibar, an aged cross-sectional survey of 305 children from three schools on Unguja was conducted to investigate the relationships between levels of excreted albumin and haemoglobin in urine and Schistosoma haematobium infection status. Diagnosis was determined by standard parasitological methods, dipstick reagents for microhaematuria, visual inspection for macrohaematuria as well as collection of case-history questionnaire data for self-diagnosis. Prevalence of infection as determined by parasitology was 53.9% and approximately, one quarter of the children examined were anaemic (<11 g dl−1). A statistically significant negative association of blood haemoglobin levels of boys and S. haematobium infection intensity status was observed (rs=−0.23, P=0.005). Through sensitivity analysis of urine-albumin values it was determined that a concentration of above >40 mg l−1, as measured with the HemoCue urine-albumin photometer, had sensitivity, specificity, positive and negative predictive values of 0.90, 0.83, 0.86 and 0.89 respectively against ‘gold-standard’ parasitology. There was a clear association of reported pain upon micturition for children with elevated urine-albumin levels, with an odds ratio of 20 to 1. Levels of excreted blood in urine were quantified with the HemoCue Plasma/Low Hb photometer. However, dipsticks remain the method of choice for urine-haemoglobin of 0.1 g l−1 and below. Urine parameters over a 24-h period were assessed in a small sub-sample. Reductions in both albumin and haemoglobin excretion were observed in 11 children 54 days after praziquantel treatment. It was concluded that these rapid, high-through-put, portable HemoCue assays could play a role in better describing and monitoring the occurrence, severity and evolution of urinary schistosomiasis disease. The urine-albumin assay has particular promise as a biochemical marker of S. haematobium induced kidney- and upper urinary tract-morbidity.
The interaction of Schistosoma haematobium and S. guineensis in Cameroon
Authors: Webster B.L. , Tchuem Tchuenté L.A. , Jourdane J. , Southgate V.R.
Published: September 2005

Interactions between schistosomes are complex with some different species being able to mate and hybridize. The epidemiology of schistosomiasis in specific areas of South West Cameroon has evolved remarkably over 30 years as a result of hybridization between Schistosoma guineensis and S. haematobium. Morphological and biological data suggest that S. haematobium replaced S. guineensis in areas of Cameroon through introgressive hybridization. Data are reported on the use of single stranded conformational polymorphism (SSCP) analysis of the nuclear ribosomal second internal transcribed spacer (ITS2) of individual schistosomes from hybrid zones of Cameroon. The data show that since 1990 S. haematobium has completely replaced S. guineensis in Loum, with S. haematobium and the recombinants still present in 2000. This study illustrates the complexities of the dynamics between S. haematobium and S. guineensis in South West Cameroon.
Development of a novel nutrition screening tool for use in elderly South Africans
Authors: Charlton KE , Kolbe-Alexander TL , Nel JH
Published: September 2005

Objective

To develop a nutrition screening tool for use in older South Africans.

Design

A cross-sectional validation study in 283 free-living and institutionalised black South Africans (60+ years).

Methods

Trained fieldworkers administered a 24-hour recall and the Mini Nutritional Assessment (MNA) screening tool, and performed anthropometric measurements and physical function tests. Cognitive function was assessed using a validated version of the Six-Item Cognitive Impairment Test. Biochemical indicators assessed included serum albumin, haemoglobin, ferritin, vitamin B12, red-blood-cell folate, cholesterol and vitamin C. The MNA was used as the gold standard against which a novel screening tool was developed using a six-step systematic approach, namely: correspondence analysis; identification of key questions; determination of internal consistency; correlational analyses with objective measures; determination of reference cut-off values for categories of nutritional risk; and determination of sensitivity and specificity.

Results

The new screening tool includes nine separate concepts, comprising a total of 14 questions, as well as measurement of mid-upper arm circumference. The new tool score was positively associated with level of independence in either basic activities of daily living (r= 0.472) or the more complex instrumental activities of daily living (r= 0.233). A three-category scoring system of nutritional risk was developed and shown to significantly characterise subjects according to physical function tests, level of independence and cognitive function. The new tool has good sensitivity (87.5%) and specificity (95.0%) compared with the MNA scoring system. It has a very high negative predictive value (99.5%), which means that the tool is unlikely to falsely classify subjects as well nourished/at risk when they are in fact malnourished.

Conclusion

A novel screening tool has been shown to have content-, construct- and criterion-related validity, and the individual items have been shown to have good internal consistency. Further validation of the tool in a new population of elderly Africans is warranted.
Obesity in South Africa: challenges for government and health professionals
Authors: Kruger H Salome , Puoane Thandi , Senekal Marjanne , van der Merwe M-Theresa
Published: September 2005

Objectives

To review data on the prevalence, causes and health consequences of obesity in South Africa and propose interventions to prevent and treat obesity and related outcomes.

Methods

Data from existing literature were reviewed with an emphasis on changing eating and activity patterns, cultural factors, perceptions and beliefs, urbanisation and globalisation. Results of studies on the health consequences of obesity in South Africans are also reviewed.

Results

Shifts in dietary intakes and activity patterns to higher fat intakes and lower physical activity are contributing to a higher prevalence of obesity. Few overweight black women view themselves as overweight, and some associate thinness with HIV/AIDS. Glucose and lipid toxicity, associated with insulin resistance, play roles in the pathogenesis of the co-morbid diseases of obesity. Elevated free fatty acids in the black population predispose obese black patients to type 2 diabetes.

Conclusion and recommendations

Obesity prevention and treatment should be based on education, behaviour change, political support, intersectoral collaboration and community participation, local actions, wide inclusion of the population, adequately resourced programmes, infiltration of existing initiatives, evidence-based planning, and proper monitoring and evaluation. Interventions should have the following components: reasonable weight goals, healthful eating, physical activity and behavioural change. Genes and mutations affecting susceptibility to the development of co-morbidities of obesity and vulnerable periods of life for the development of obesity should be prioritised. Prevention should be managed in community services, identification of high-risk patients in primary healthcare services and treatment of co-morbid diseases in hospital services.
Prevalence and determinants of stunting and overweight in 3-year-old black South African children residing in the Central Region of Limpopo Province, South Africa
Authors: Mamabolo Ramoteme L , Alberts Marianne , Steyn Nelia P , Delemarre-van de Waal Henriette A , Levitt Naomi S
Published: September 2005

Objectives

To determine the prevalence of stunting, wasting and overweight and their determinants in 3-year-old children in the Central Region of Limpopo Province, South Africa.

Design

Prospective cohort study.

Setting

Rural villages in the Central Region of the Limpopo Province, South Africa.

Subjects

One hundred and sixty-two children who were followed from birth were included in the study. Anthropometric measurements and sociodemographic characteristics of the children were recorded.

Results

Height-for-age Z-scores were low, with a high prevalence of stunting (48%). The children also exhibited a high prevalence of overweight (22%) and obesity (24%). Thirty-one (19%) children were both stuntedandoverweight. Gaining more weight within the first year of life increased the risk of being overweight at 3 years by 2.39 times (95% confidence interval (CI) 1.96–4.18) while having a greater length at 1 year was protective against stunting (odds ratio (OR) 0.41; 95% CI 0.17–0.97). Having a mother as a student increased the risk for stunting at 3 years by 18.21 times (95% CI 9.46–34.74) while having a working mother increased the risk for overweight by 17.87 times (95% CI 8.24–38.78). All these factors also appeared as risks or as being protective in children who were both overweight and stunted, as did living in a household having nine or more persons (OR 5.72; 95% CI 2.7–12.10).

Conclusion

The results of this study highlight the importance of evaluating anthropometric status in terms of both stunting and overweight. Furthermore, it is important to realise the importance of normal length and weight being attained at 1 year of age, since these in turn predict nutritional status at 3 years of age.
Reducing iron deficiency anaemia due to heavy menstural blood loss in Nigerian rural adolescents. Reprinted from Public Health Nutrition Volume 1 (4), 249–257, 1998
Authors: Barr Fiona , Brabin Loretta , Agbaje Shola , Buseri Feikumo , Ikimalo John , Briggs Nimi
Published: September 2005

Objective

Menstrual disorders are common in young women, and heavy menstrual blood losses (MBL) are an important cause of anaemia. Menstrual morbidity normally goes untreated in developing countries where cultural barriers also serve to make the problems. We investigated the prevelance of menstrual morbidity, and measured MBL and its relationship to iron deficiency in a rural adolescent population. The rationale was to assess whether or not reducing heavy MBL could be part of a strategy to reduce iron deficiency anaemia.

Setting

Rural village in south-east Nigeria.

Design

Cross-sectional survey.

Subjects

The studdy included all non-pregnant, unmarried nulliparous girls (< 20 years) who had menstruated, and who lived in K'Dere village.

Methods

A field worker allocated to each girl completed a questionnaire, and supervised recovery and collection of soiled pads and ensured blood sampling. MBL was measured using the standard alkaline haematin method. Haemoglobin (HB), serum iron, transferin saturation and protoporphyrin levels (ZPP) were also measured.

Results

307 girls completed MBL measurements; 11.9% refused to participate. 12.1% had menorrhagia (> 80 ml);. median MBL was 33.1 ml. Menorrhagia was more frequent in girls who had menstruated for > 2 years (p= 0.048), and had longer duration of meneses (p < 0.001). Iron status as measured by haematocrit, serum iron, transferrin saturation and ZPP values was inversely related to MBL. Neither height nor body mass index for age was associated with current iron status.

Conclusions

The level of menorrhagia detected (12%) may be an ‘expected’ level for a condition which often has no underlying pathology. Heavy MBL is one of the most important factors contributing to iron deficiency anaemia. Measures are needed to alleviate menstrual disorders and improve iron status. Oral contraceptives can be part of a strategy to reduce anaemia, particularly for adolescents at high risk of unwanted pregnancies.
Nebulin regulates the assembly and lengths of the thin filaments in striated muscle
Authors: McElhinny Abigail S. , Schwach Catherine , Valichnac Melinda , Mount-Patrick Sarah , Gregorio Carol C.
Published: September 2005

In many tissues, actin monomers polymerize into actin (thin) filaments of precise lengths. Although the exact mechanisms involved remain unresolved, it is proposed that “molecular rulers” dictate the lengths of the actin filaments. The giant nebulin molecule is a prime candidate for specifying thin filament lengths in striated muscle, but this idea has never been proven. To test this hypothesis, we used RNA interference technology in rat cardiac myocytes. Live cell imaging and triple staining revealed a dramatic elongation of the preexisting thin filaments from their pointed ends upon nebulin knockdown, demonstrating its role in length maintenance; the barbed ends were unaffected. When the thin filaments were depolymerized with latrunculin B, myocytes with decreased nebulin levels reassembled them to unrestricted lengths, demonstrating its importance in length specification. Finally, knockdown of nebulin in skeletal myotubes revealed its involvement in myofibrillogenesis. These data are consistent with nebulin functioning as a thin filament ruler and provide insight into mechanisms dictating macromolecular assembly.
Evolution of clinical pattern of parthenium dermatitis: a study of 74 cases
Authors: Sharma Vinod K. , Sethuraman Gomathy , Bhat Radhakrishna
Published: September 2005

Our aim was to study the evolution of clinical pattern of parthenium dermatitis. Patients with clinical picture consistent with parthenium dermatitis for 3 years or more along with positive patch test to parthenium were studied. Patients were questioned regarding the site(s) of dermatitis at the onset and change in localization in the following years. Patients were classified into airborne contact dermatitis, chronic actinic dermatitis (CAD) pattern or mixed pattern dermatitis. There were 74 patients (49 men and 25 women) with an age range of 22–70 years and the mean duration of 7.7 years. 60 (39 men and 21 women) patients had airborne contact dermatitis, 5 mixed pattern and 9 CAD pattern at the onset. Of the 60 patients with airborne contact dermatitis, 27 (19 men and 8 women) changed to CAD pattern and 11 (6 men and 5 women) to mixed pattern after an average period of 4.2 years. Of the 19 patients photopatch‐tested with parthenium, 3 showed photoallergic reaction and the other 3 showed photoaggravation. Our results suggest that the clinical pattern of parthenium dermatitis undergoes a significant change after the onset, i.e. progresses from airborne contact dermatitis to mixed pattern or CAD pattern.
Gene transcripts as potential diagnostic markers for allergic contact dermatitis
Authors: Hansen Malene Barré , Skov Lone , Menné Torkil , Olsen Jorgen
Published: September 2005

The standard procedure for diagnosing allergic contact dermatitis is to perform a patch test. Because this has several disadvantages, the development of a new in vitro test system would be of immense value. Gene transcripts that distinguish allergics from non‐allergics may have the potential to serve as the molecular basis for such a diagnostic tool. In this study, we use the microarray technology in the identification of differentially expressed genes in allergen‐stimulated peripheral blood mononuclear cells (PBMCs) from 3 chromium‐allergic patients versus 3 healthy controls. Using an Affymetrix GeneChip®, the gene expression was analysed in PBMC cultures grown with 100 µg/ml CrCl3 or in media alone for 24 hr. A total of 26 genes were differentially expressed by more than twofold (P < 0.01) in allergen‐activated PBMCs from patients compared with controls. 18 of these were upregulated, whereas 8 were downregulated. The expression of 1 downregulated gene, CASP8, was also found specifically and significantly reduced in an expanded population including 4 additional chromium allergic patients and 1 additional control subject by real‐time reverse transcriptase polymerase chain reaction (RT‐PCR) analysis. The expression of 2 upregulated genes, ETS2 and CISH, correlated with a high‐proliferative response following CrCl3 exposure. Additionally, real‐time RT‐PCR analysis indicated that the same gene expression changes are valid for nickel allergics, potentially making the expression profile more widely available. The 26 differentially expressed genes identified in this study may potentially function as diagnostic markers for contact sensitivity.
Acrylates induced rhinitis and contact dermatitis
Authors: Torres M. C. , Linares T. , Hernandez M. D.
Published: September 2005

Acrylates are a well‐known cause of occupational contact dermatitis due to its widespread use in several settings such as dentistry, orthopaedic surgery, graphic industry and cosmetics. We describe the case of a manicurist who developed occupational rhinitis and allergic contact dermatitis induced by the application of acrylic‐sculptured nails.
SNP detection and genetic mapping of porcine genes encoding enzymes in hepatic metabolic pathways and evaluation of linkage with carcass traits
Authors: Ponsuksili S. , Chomdej S. , Murani E. , Bläser U. , Schreinemachers H.‐J. , Schellander K. , Wimmers K.
Published: September 2005

We have previously identified and mapped porcine expressed sequence tags (ESTs) derived from genes that are preferentially expressed in liver. The aim of the present study was to identify single nucleotide polymorphisms (SNPs) in porcine genes encoding enzymes in hepatic metabolic pathways and use the SNPs for mapping. Furthermore, these genes, which are involved in utilization and partitioning of nutrients, were examined for their effects on carcass and meat quality traits by linkage analyses. In total, 100 ESTs were screened for SNPs by single strand conformation polymorphism analyses across a diverse panel of animals with a 36% success rate. Twelve of 36 polymorphic loci segregated in a three‐generation Duroc × Berlin Miniature Pig (F2) resource population, the DUMI resource population, and were genetically mapped. Interval mapping of the corresponding chromosomes was performed to verify mapping of the genes within quantitative trait loci (QTL) regions detected in this resource population. QTL with genome‐wide significance were detected in the vicinity of GNMT, ESTL147 and HGD. These loci therefore are positional candidate genes.
Light penetration in soil and particulate minerals
Authors: Ciani A. , Goss K.‐U. , Schwarzenbach R. P.
Published: September 2005

Knowledge of light penetration in soils is of particular interest for photolytic degradation of pesticides, for laser‐induced fluorescence spectroscopy and remote sensing, and for understanding better the germination of seeds. To date little information has been available in the literature on this topic. In this paper light penetration in soils is determined successfully using diffuse reflectance and transmittance spectroscopy and the relatively simple Kubelka–Munk model. Using the latter model of light propagation in turbid media, the optical properties of kaolinite, montmorillonite, barium sulphate, goethite and 19 different soils were determined in the wavelength range 275–700 nm. In particular, the light absorption coefficient, k, and light scattering coefficient, s, were determined. The depth at which the light intensity at the surface is reduced by 99% (light penetration depth) and the depth of the sample contributing to the measured reflected radiation (information depth) could also be calculated from k and s. For kaolinite, the light penetration depth ranged between 10 and 200 µm for wavelengths between 275 and 700 nm, respectively; the information depth was between 5 and 80 µm. For soils, the penetration depth was in the range 17–110 µm at 275 nm and 120–300 µm at 700 nm, and the information depth was in the range 8–60 µm at 275 nm and 60–175 µm at 700 nm. Hence, the information depth is about half the penetration depth for media with reflectance smaller than 0.7 (e.g. soils). For dry soils, an empirical relationship was established between the light absorption coefficient and the amount of particle‐size fractions. The effect of water content was also investigated: addition of water to kaolinite reduced its scattering coefficients, whereas the absorption coefficient was hardly affected. For the soils, addition of water had a more complex mode of action affecting both absorption and scattering coefficients. With the measured optical properties of dry minerals and soils it is possible to calculate light intensity profiles with depth and to quantify photochemical processes occurring in these media.
Transformation of haematite and Al‐poor goethite to Al‐rich goethite and associated yellowing in a ferralitic clay soil profile of the middle Amazon Basin (Manaus, Brazil)
Authors: Fritsch E. , Morin G. , Bedidi A. , Bonnin D. , Balan E. , Caquineau S. , Calas G.
Published: September 2005

The red and yellow colours of ferralitic soils in the tropics have for long intrigued pedologists. We have investigated the upward yellowing in a 10‐m thick profile representative of the Ferralsols of the plateaux of the Manaus region of Brazil. We determined changes in the nature and crystal chemistry of their Fe oxides by optical and Mössbauer spectroscopy as well as Rietveld refinement of X‐ray diffraction patterns. We attribute the upward yellowing of the soil to a progressive transformation of the Fe oxides at nearly invariant iron contents. Aluminium in contrast is strongly mobilized in the uppermost clay‐depleted topsoil where there is preferential dissolution of kaolinite and crystallization of gibbsite. Haematite decreases from 35 to 10% of the Fe oxides from the bottom to the top of the profile and the particles become smaller (75–10 nm). Its Al for Fe‐substitution remains almost unchanged (10–15 mol %). The average Al‐substitution rate of goethite increases from 25 to 33 mol %, and its mean crystal diameter remains in the range 20–40 nm. The proportion of Al‐rich goethite (33 mol %) increases at the expense of less Al‐substituted Fe oxides (haematite and goethite). This conversion with restricted transfer of iron means that the amount of Al stored in Fe oxides gradually increases. Kaolinite, haematite and Al‐poor goethite are thus witnesses of earlier stages of ferralitization of the soil. In contrast, Al‐rich goethite and gibbsite initiate the alitization (or bauxitization) of the soil. They correspond to the last generation of soil minerals, which most likely reflects the present‐day weathering conditions. The progressive replacement of kaolinite, haematite and Al‐poor goethite by new generations of Al‐rich goethite and gibbsite attests to greater activities of water and aluminium and smaller activity of aqueous silica in the topsoil than in the subsoil. We interpret this as a consequence of longer periods of wetting in the topsoil that could result from soil aging, more humid climate or both.
Modifications to the Freundlich equation to describe anion sorption over a large range and to describe competition between pairs of ions
Authors: Barrow N. J. , Cartes P. , Mora M. L.
Published: September 2005

We measured sorption of selenite and phosphate, both separately and in competition, in a Chilean Andisol. We also used previously published data for competitive sorption of arsenate and phosphate by a clay subsoil. We wrote computer programs that allowed us to compare the fits of differing versions of equations to describe individual sorption and competitive sorption. For the selenite–phosphate data, the index term of the Freundlich equation decreased as concentration increased. This was described using the Sibbesen modification of the Freundlich equation. This modification was then included in competition equations. For both the selenite–phosphate and the arsenate–phosphate data, competition was not ‘symmetrical’, that is, the competition terms were not reciprocals of each other. We think this occurred because competition between ions is not only competition for adsorption sites but also involves electrical effects that follow penetration of the surface.
Sulphur speciation and biogeochemical cycling in long‐term arable cropping of subtropical soils: evidence from wet‐chemical reduction and S K‐edge XANES spectroscopy
Authors: Solomon D. , Lehmann J. , Lobe I. , Martinez C. E. , Tveitnes S. , Du Preez C. C. , Amelung W.
Published: September 2005

Agriculture has claimed a large share of terrestrial environments in the tropics and subtropics through cultivation of native grasslands or forests. The impact of this anthropogenic change on speciation, dynamics, and ecological significance of sulphur (S) compounds is still poorly understood. We combined degradative wet‐chemical reduction and S K‐edge X‐ray absorption near edge structure (XANES) spectroscopy techniques to evaluate the impact of long‐term agricultural management of native grassland soils in South African Highveld on the amount, form and dynamics of S species. Sulphur XANES in the humic substances extracted by 0.1 m NaOH/0.4 m NaF solution showed the presence of strongly reduced (polysulphides, disulphides, thiols, monosulphides and thiophenes), intermediate (sulphoxides and sulphonates) and strongly oxidized (ester sulphates) organic‐S. It showed that strongly oxidized‐S is the predominant form (39–54%) of the total organic‐S in the humic substances, and organic‐S in the intermediate oxidation state represented 30–37% (78–93% of which was attributed to sulphonates). The strongly reduced organic‐S comprised only 17–24% of the total organic‐S. We did not find a close correlation between the results of a degradative wet‐chemical procedure and XANES spectroscopy conducted in both the bulk soils (ester SO4‐S from XANES versus HI‐fractionation, r = 0.27; P < 0.05) and the humic substance extracts (ester SO4‐S from XANES versus HI‐fractionation, r= 0.39; P < 0.05). The ratio of reduced‐S to strongly oxidized‐S (R‐S/O‐S) in the humic substances decreased from 0.61 to 0.21, while the ratio of intermediate‐S to strongly oxidized‐S (I‐S/O‐S) declined from 0.93 to 0.61 after 90 years of arable cropping of the native grassland soils. Hence, there was a shift in oxidation state towards strongly oxidized‐S (+6) and, thereby, a change in the relative proportion of the organic‐S moieties associated with each oxidation state following cultivation of the native grassland soils. Therefore, we conclude that changes in land‐use practice brought about not only quantitative change but also altered the composition of organic‐S functional groups in these native subtropical grassland soils.
Modelling cation transport and pH buffering during unsaturated flow through intact subsoils
Authors: Ludwig B. , Beese F. , Michel K.
Published: September 2005

Prediction of cation transport during unsaturated flow through soils is complex, and chemical models are necessary for the purpose. Our objectives were to determine whether the reactions considered in the model PHREEQC2 were appropriate to predict cation transport in soils when small amounts of CaCl2 or acid are added and to investigate the usefulness of different parameterization approaches. Undisturbed columns of three subsoils were irrigated for 2 years with 4 mm day−1 at 8°C. The experiments were (A) irrigation with 1 mm and 5 mm CaCl2 and (B) irrigation with 1 mm HCl. The model PHREEQC2 was used to calculate one‐dimensional transport, inorganic complexation, dissolution or precipitation of Al(OH)3, AlOHSO4 and CaCO3 and multiple cation exchange. We compared three models: one with no adjustable parameters, a second with optimized solubilities within a reported range, pCO2 and cation exchange capacity (CEC), and a third which also included an optimization of the exchange coefficients. The first was of little use to predict cation transport in soils. The second was appropriate for one of the soils, but an optimization of the exchange coefficients was required for an accurate description and prediction of cation transport for the others. The CEC accessible for seepage water varied between 50% and 100% of the total CEC. Our results indicate that for a reliable assessment of cation transport in soils during unsaturated flow, calibration experiments are required. The parameter optimization program PEST in combination with PHREEQC2 gave a better understanding of cation transport in undisturbed soil.
Composition of organic matter in a subtropical Acrisol as influenced by land use, cropping and N fertilization, assessed by CPMAS 13C NMR spectroscopy
Authors: Dieckow J. , Mielniczuk J. , Knicker H. , Bayer C. , Dick D. P. , Kögel‐Knabner I.
Published: September 2005

We know much about the influence of management on stocks of organic matter in subtropical soils, yet little about the influence on the chemical composition. We therefore studied by CPMAS 13C NMR spectroscopy the composition of the above‐ground plant tissue, of the organic matter of the whole soil and of silt‐ and clay‐size fractions of the topsoil and subsoil of a subtropical Acrisol under grass and arable crops. Soil samples were collected from three no‐till cropping systems (bare soil; oats−maize; pigeon pea + maize), each receiving 0 and 180 kg N ha−1 year−1, in a long‐term field experiment. Soil under the original native grass was also sampled. The kind of arable crops and grass affected the composition of the particulate organic matter. There were no differences in the composition of the organic matter in silt‐ and clay‐size fractions, or of the whole soil, among the arable systems. Changes were observed between land use: the soil of the grassland had larger alkyl and smaller aromatic C contents than did the arable soil. The small size fractions contain microbial products, and we think that the compositional difference in silt‐ and clay‐size fractions between grassland and the arable land was induced by changes in the soil's microbial community and therefore in the quality of its biochemical products. The application of N did not affect the composition of the above‐ground plant tissue nor of the particulate organic matter and silt‐size fractions, but it did increase the alkyl C content in the clay‐size fraction. In the subsoil, the silt‐size fraction of all treatments contained large contents of aromatic C. Microscopic investigation confirmed that this derived from particles of charred material. The composition of organic matter in this soil is affected by land use, but not by variations in the arable crops grown.
Poorly crystalline mineral phases protect organic matter in acid subsoil horizons
Authors: Kleber M. , Mikutta R. , Torn M. S. , Jahn R.
Published: September 2005

Soil minerals are known to influence the biological stability of soil organic matter (SOM). Our study aimed to relate properties of the mineral matrix to its ability to protect organic C against decomposition in acid soils. We used the amount of hydroxyl ions released after exposure to NaF solution to establish a reactivity gradient spanning 12 subsoil horizons collected from 10 different locations. The subsoil horizons represent six soil orders and diverse geological parent materials. Phyllosilicates were characterized by X‐ray diffraction and pedogenic oxides by selective dissolution procedures. The organic carbon (C) remaining after chemical removal of an oxidizable fraction of SOM with NaOCl solution was taken to represent a stable organic carbon pool. Stable organic carbon was confirmed as older than bulk organic carbon by a smaller radiocarbon (14C) content after oxidation in all 12 soils. The amount of stable organic C did not depend on clay content or the content of dithionite–citrate‐extractable Fe. The combination of oxalate‐extractable Fe and Al explained the greatest amount of variation in stable organic C (R2 = 0.78). Our results suggest that in acid soils, organic matter is preferentially protected by interaction with poorly crystalline minerals represented by the oxalate‐soluble Fe and Al fraction. This evidence suggests that ligand exchange between mineral surface hydroxyl groups and negatively charged organic functional groups is a quantitatively important mechanism in the stabilization of SOM in acid soils. The results imply a finite stabilization capacity of soil minerals for organic matter, limited by the area density of reactive surface sites.
Trace magnetic minerals to detect redox boundaries and drainage effects in a marshland soil in western France
Authors: Mathé V. , Lévêque F.
Published: September 2005

The marshlands of western France provide the opportunity to relate the magnetic properties of a recent sedimentary clay soil to pedogenesis, including the impact of agriculture and drainage on magnetic mineralogy. We studied a plot of drained land that had been ploughed up to 1998 and under grass since. A new thermomagnetic method was used to identify and to quantify roughly the magnetic minerals, which represent less than 1 g kg−1. The most abundant Fe oxides are haematite (45%) and goethite (45%). However, trace amounts of the ferrimagnetic minerals maghemite (4%), magnetite (3%) and, to a lesser extent, iron sulphides (1%) provide most of the magnetic signal. This signal allowed us to identify magnetic horizons that relate to the soil horizons. The topsoil is characterized by a strong magnetic enhancement (4‐fold), and the thickness of this layer increases close to the drains. Relative contents of ferrimagnetic phase also increase laterally with decreasing distance to the drains. Magnetic enhancement coincides with the most aerated and developed layer, in which water circulation, root colonization and hence soil fertility are greater. Ferromagnetic minerals sensu lato, especially maghemite and magnetite, can be considered as mineralogical tracers partly and indirectly reflecting soil fertility of these clay‐rich marshland soils.
Effect of soil depth on acid properties of humic substances extracted from an ombrotrophic peat bog in northwest Spain
Authors: Gondar D. , López R. , Fiol S. , Antelo J. M. , Arce F.
Published: September 2005

The most southerly ombrotrophic peat bogs in Europe are in Galicia (northwest Spain). The humic matter in them originates from chemical processes in anaerobic conditions. We studied the acid properties of fulvic acids and humic acids isolated from two peat horizons of an ombrotrophic peat bog by potentiometric titration. Solutions containing 25, 50 and 100 mg l−1 of each humic substance were titrated at ionic strengths 0.005 m, 0.01 m and 0.1 m (with KNO3 as the inert electrolyte). Charge curves were analysed with a Donnan model to determine the intrinsic proton binding parameters. The concentration of the humic substance affected the charge curves more significantly at pH exceeding 6, and tended to disappear at greater concentrations. The proton binding conditional constants decreased with increasing ionic strength, this effect being more significant in the carboxylic groups with less affinity for protons. The proton binding constant of the carboxyl groups in a fulvic acid was one order of magnitude less than the value for the corresponding humic acid, whereas for the phenolic groups the values for both fractions were similar. The total content of acid groups was approximately 2 mol kg−1 greater in the fulvic fraction than in the humic fraction. Both humic fractions from the lower horizon contained more acid groups than those from the upper horizon, mainly because the content of carboxyl groups increases with soil depth. Therefore, the humic substances in the lower horizon of the peat will be more negatively charged, which will affect their solubility and the binding of metal ions.