bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of changes in pH, ionic strength, and sulphate concentration on the CEC of temperate acid forest soils
Authors: MATSCHONAT G. , VOGT R.
Published: August 2005

As the acidity of rain diminishes, changes in the pH, ionic strength, and ion activities of the soil solution will influence the charge characteristics of soil. We have investigated the response of cation exchange capacity (CEC) of three acid forest soils of variable charge to small changes in pH, ionic strength, and SO2−4concentration. The variable charge for these temperate soils has the same significance as for tropical soils and those from volcanic ash. Maximum absolute increase in CEC on increasing pH by 0·2–0·5 units reached 5 cmolckg‐1in O horizons. The increase in CEC on doubling ionic strength in EA and Bsh horizons of a Cambic Podzol was about half that amount, but relative gains compared to effective CEC were 65 and 46%, respectively. For other soil horizons, absolute changes were smaller, and relative changes were between 10 and 30%. Halving the SO2−4concentration significantly influenced CEC only in some samples. Both pH and ionic strength must be adjusted with care when determining CECcof acid forest soils. Decreasing acid deposition will not inevitably increase CECcbecause in some soils pH effects may be balanced by simultaneous decrease in ionic strength.
A hard sandy‐loam soil from semi‐arid Northern Cameroon: I. Fabric of the groundmass
Authors: LAMOTTE M. , BRUAND A. , HUMBEL F.X. , HERBILLON A.J. , RIEU M.
Published: August 2005

In semi‐arid tropics soil hardening may reduce both water infiltrability and biological activity, thus inducing the development of large almost bare areas. A sandy‐loam soil with contrasting loose and underlying hard horizons was studied in the southern plain of the Chad basin. The fabrics of these horizons were studied using combined sieving and sedimentation techniques, mercury porosimetry and scanning electron microscopy. The horizons had similar particle size distributions of the skeleton grains. The hard horizon differs by a small increase in its fine clay (< 0·2 μm) content. The hardness is closely related to a fabric with clay coatings on the skeleton grains and clay wall‐shaped bridges linking the latter. This induces a strong continuity of the solid phase. This fabric requires a minimum of clay content (6%) to make the coatings and the wail‐shaped bridges, and it can be 30% less porous than the loose horizon, without any change in the packing of the skeleton grains. These characteristics of the fabric of the hard horizon are like those of fragipans elsewhere. The continuity of the solid phase, from the microscopic to the macroscopic scale, as well as the absence of a network of cracks explains the considerable strength of the hard horizon, and consequently the difficulties for water infiltration, root penetration and tillage.
Release of Al by hydroxy‐interlayered vermiculite and hydroxy‐interlayered smectite during determination of cation exchange capacity in fine earth and rock fragments fractions
Authors: CORTI G. , AGNELLI A. , UGOLINI F.C.
Published: August 2005

The fine earth (<2 mm) and rock fragments (>2 mm) fractions of two soils derived from Oligocene sandstone have been examined to assess the origin of the discrepancies between cation exchange capacity (CEC) and effective CEC (ECEC). The soils differ in terms of acidity: soil A is more acid than soil B. When the A samples are treated with BaCl2, the solution became sufficiently acid (pH < 4·5) to dissolve and to maintain Al in solution. From these samples more Al is released than base cations. Aluminium was continuously replenished even after 192 h, so that the ECEC was always larger than the CEC. Samples from soil B contain less H and Al ions, and the BaCl2 solution could not lower the pH below 5·0. In these samples little Al is released, and the base cations dominate the exchangeable pool of ions. This Al can be considered to be exchangeable, and a good agreement exists between the ECEC and the CEC. The source of non‐exchangeable Al in the A samples is the OH‐Al polymers of the hydroxy‐interlayered vermiculite (HIV) and hydroxy‐interlayered smectite (HIS) that tend to dissolve during the BaCl2 treatments. In the less acid B samples the Al polymers are not affected by BaCl2 treatment. Different results were obtained when the clays, extracted from an Na‐dispersed suspension, were treated with BaCl2 solution. Because the clays are no longer acid, no H+ is released, and the OH‐Al polymers are not dissolved. Therefore, the saturating ions play an important role in the dissolution of the OH‐Al polymers and cause differences between the CEC and ECEC. We discount organic matter and specifically Al‐organo complexes as a source of non‐exchangeable Al. Both A and B soils contain very similar pyrophosphate‐extractable Al, but show substantial differences in the amount of exchangeable Al.
Dissolved organic matter sorption on sub soils and minerals studied by13C‐NMR and DRIFT spectroscopy
Authors: KAISER K. , GUGGENBERGER G. , HAUMAIER L. , ZECH W.
Published: August 2005

Sorption on the mineral matrix is an important process restricting the movement of dissolved organic matter (DOM) in soils. In this study, we aimed to identify the chemical structures responsible for the retention of DOM by sorption experiments with total DOM and acidic humic substances (AHS), containing humic and fulvic acids, on soil samples and minerals (goethite, ferrihydrite, and amorphous Al(OH)3). The AHS remaining in solution after sorption were studied by13C nuclear magnetic resonance (NMR) analysis, and total DOM and AHS for bed on the surfaces of minerals by diffuse reflectance Fourier‐transform infrared (DRIFT) spectroscopy. The soil samples were taken from strongly sorbing Bw horizons of two Inceptisols rich in pedogenetic Fe (29 and 35 g kg−1) and containing little C (7 and 22 g kg−1). The13C‐NMR spectra showed that sorption causes a preferential removal of aromatic and carboxyl C from the solution, whereas alkyl‐C accumulates in the solution. No change was observed for O‐alkyl C. The DRIFT spectra of sorbed total DOM and AHS showed a relative increase of the band intensity of carboxyl groups compared to DOM in the initial solution, confirming the importance of those groups for the sorption to mineral surfaces. The spectra also indicated reactions of carboxyl groups with metals at the mineral surfaces. The extent to which the carboxyl groups are bound depended on the surface coverage with DOM and the type of mineral.
Phenolic and carbohydrate signatures of organic matter in soils developed under grass and forest plantations following changes in land use
Authors: SANGER L.J. , ANDERSON J.M. , LITTLE D. , BOLGER T.
Published: August 2005

Comparisons were made between the phenolic and carbohydrate signatures of soil profiles developed under grass, spruce and ash stands. Samples were collected from a brown earth soil which was originally under the same land use, but over the past 43 years has supported different monocultures. Distinct signatures associated with each litter type were recorded in individual profiles. A relatively undecomposed phenolic fraction from lignin and hydrolysable carbohydrate fraction from plants had accumulated in the soils under spruce and ash. This largely reflected the quantity and quality of the litter inputs from the spruce and ash compared with the grass. The phenolic and hydrolysable carbohydrate fractions accounted for as much as 60% of the total organic carbon concentration in the deep horizons. In the grassland profile both fractions were more decomposed than under ash and spruce suggesting that the forest profiles had rapidly accumulated a carbon pool with a comparatively slow rate of decomposition. This was most apparent from the spruce profile (which contained 398 mg g−1 C carbohydrate hydrolysed using trifluoracetic acid (TFA) in the C horizon compared with 165 and 45 mg g−1 C under ash and grass respectively). We conclude that the decay rate of these fractions is a function of the vegetation type.
Ecotoxicological effects of fluorine deposits on microbial biomass and enzyme activity in grassland
Authors: TSCHERKO D. , KANDELER E.
Published: August 2005

The influence of atmospheric fluoride deposits on the soil microbial biomass and its enzyme activities was investigated near the aluminium smelter at Ranshofen, Upper Austria. Soil samples at various distances from the emission source were analyzed for water‐extractable F and microbial activity. The water‐extractable F contents at the sites examined reflected the gradient of F exposure (10 to 189 mg F kg−l dry soil). The microbial activities increased with distance from the emission source and were inversely correlated with the degree of F contamination. The linear correlation coefficients between the water‐extractable F concentrations and the microbial biomass, dehydrogenase and arylsulphatase activity were r=−0·8, −0·86 and −0·84, respectively. In the most contaminated soil (up to 189 mg F kg−1), the microbial activities were only 5–20% of those in the unpolluted soil. The microbial biomass and dehydrogenase activity decreased substantially where the concentration of F exceeded 100mgkg−1, whereas arylsulphatase activity was already inhibited at 20 mg kg−1. The accumulation of organic matter near the smelter (123 mg F kg−1) also indicated severe inhibition of the microbial activity by F. Our investigations show that the ratio of arylsulphatase to microbial biomass can be used as a sensitive index for evaluating environmental stress such as F Contamination.
Solubility control of Cu, Zn, Cd and Pb in contaminated soils
Authors: McBRIDE M. , SAUVE S. , HENDERSHOT W.
Published: August 2005

We developed a semiempirical equation from metal complextion theory which relates the metal activity of soil solutions to the soil's pH, organic matter content (OM) and total metal content (MT). The equation has the general form:
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where pM is the negative logarithm (to base 10) of the metal activity, and a, b and c are constants. The equation successfully predicted free Cu2+ activity in soils with a wide range of properties, including soils previously treated with sewage sludge. The significant correlation of pCu to these measured soil properties in long‐contaminated soils suggests that copper activity is controlled by adsorption on organic matter under steady state conditions. An attempt was made from separate published data to correlate total soluble Cu, Zn, Cd and Pb in soils to soil pH, organic matter content and total metal content. For Cu, the total Cu content of the soil was most highly correlated with total soluble Cu. Similarly, total soluble Zn and Cd were correlated with total metal content, but were more strongly related to soil pH than was soluble Cu. Smaller metal solubility in response to higher soil pH was most marked for Zn and Cd, metals that tend not to complex strongly with soluble organics. The organic matter content was often, but not always, a statistically significant variable in predicting metal solubility from soil properties. The solubility of Pb was less satisfactorily predicted from measured soil properties than solubility of the other metals. It seems that for Cu at least, solid organic matter limits free metal activity, whilst dissolved organic matter promotes metal solubility, in soils well‐aged with respect to the metal pollutant. Although total metal content alone is not generally a good predictor of metal solubility or activity, it assumes great importance when comparing metal solubility in soils having similar pH and organic matter content.
Measurement of volumetric water content by TDR in saline soils
Authors: WYSEURE G.C.L. , MOJID M.A. , MALIK M.A.
Published: August 2005

Time‐domain reflectometry (TDR) evaluates the bulk dielectric constant, K, of the soil by measuring the travel time of an electromagnetic pulse through a sensor, and through it estimates the volumetric water content. We show that for saline soils the effects of conductivity and frequency on the travel time cannot be neglected and that, as a result, TDR systematically overestimates the water content in saline soils. Simultaneously the bulk electrical conductivity of soils can be estimated by TDR. The equivalent impedance after multiple reflections is related to the bulk electrical conductivity, σ This relation differs from sensor to sensor and requires calibration for each individual sensor.

A method is proposed for correcting the volumetric water content in saline soils. First, the bulk electrical conductivity, o, is estimated from the equivalent impedance at a specific equivalent distance of cable, several times the actual length of the sensor. The zero‐salinity dielectric constant, KO, of this soil is obtained by correcting the apparent K as a function of the measured bulk electrical conductivity. The volumetric water content is estimated from Ko. The correction of K is a function of the equivalent frequency of the electromagnetic pulse. The imaginary part of the dielectric constant is primarily due to ohmic losses. The model, which calculates the velocity of propagation of the electromagnetic pulse and which takes into consideration the imaginary part, performs reasonably well. An empirical approach based on calibration gave slightly better results.
Differential Contribution of Nitric Oxide and cGMP to the Stimulatory Effects of Growth Hormone‐Releasing Hormone and Low‐Concentration Somatostatin on Growth Hormone Release from Somatotrophs
Authors: Luque R. M. , Rodríguez‐Pacheco F. , Tena‐Sempere M. , Gracia‐Navarro F. , Malagón M. M. , Castaño J. P.
Published: August 2005

There is increasing evidence that nitric oxide (NO) produced by NO synthase (NOS), and their signalling partners, guanylyl cyclase and cGMP, play a relevant role in growth hormone (GH) secretion from somatotrophs. We previously demonstrated that both GH‐releasing hormone (GHRH; 10−8 M) and low concentrations of somatostatin (10−15 M) stimulate pig GH release in vitro, whereas a high somatostatin concentration (10−7 M) inhibits GHRH‐induced GH secretion. To ascertain the possible contribution of the NOS‐NO and guanylyl cyclase‐cGMP routes to these responses, cultures of pituitary cells from prepubertal female pigs were treated (30 min) with GHRH (10−8 M) or somatostatin (10−7 or 10−15 M) in the absence or presence of activators or blockers of key steps of these signalling cascades, and GH release was measured. Two distinct activators of NO route, SNAP (5 × 10−4 M) or L‐AME (10−3 M), similarly stimulated GH release when applied alone (with this effect being blocked by 10−7 M somatostatin), but did not alter the stimulatory effect of GHRH or 10−15 M somatostatin. Conversely, two NO pathway inhibitors, NAME (10−5 M) or haemoglobin (20 µg/ml) similarly blocked GHRH‐ or 10−15 M somatostatin‐stimulated GH release. 8‐Br‐cGMP (10−8 to 10−4 M) strongly stimulated GH release, suggesting that cGMP may function as a subsequent step in the NO pathway in this system. Interestingly, 10−7 M somatostatin did not inhibit the stimulatory effect of 8‐Br‐cGMP. Moreover, although 8‐Br‐cGMP did not modify the effect of GHRH, it enhanced GH release stimulated by 10−15 M somatostatin. Accordingly, a specific guanylyl cyclase inhibitor, LY‐83, 583 (10−5 M) did not alter 10−15 M somatostatin‐induced GH release, whereas it blocked GHRH‐induced GH secretion. These results demonstrate for the first time that the NOS/NO signalling pathway contributes critically to the stimulatory effects of both GHRH and low‐concentration somatostatin on GH release, and that, conversely, the subsequent guanylyl cyclase/cGMP step only mediates GHRH‐ and not low‐concentration somatostatin‐induced GH secretion from somatotrophs.
A prosthodontic management alternative for scleroderma patients
Authors: YENISEY M. , KÜLÜNK T. , KURT Ş. , URAL Ç.
Published: August 2005

summary  Hardening of the skin around the mouth causes the oral opening to become limited in scleroderma patients. A maximal oral opening that is smaller than the size of a complete denture can make prosthetic treatment challenging. This clinical report presents the prosthodontic management of a total edentulous patient with microstomia induced by scleroderma. Sectional mandibular and maxillary trays and a collapsed mandibular denture were fabricated for the total edentulous patient. With the use of lingual midline hinge, the collapsed denture was successfully and easily inserted and provided adequate function in the patient's mouth. The cast hinge design reduced the overall costs and simplified the laboratory technique.
Use of biofunctional prosthetic system following partial maxillary resection: a clinical report
Authors: NEKORA‐AZAK A. , EVLIOGLU G. , ÖZDEMIR‐KARATAŞ M. , KESKIN H.
Published: August 2005

summary  This clinical report describes the prosthodontic rehabilitation of an edentulous patient with a maxillary defect using the biofunctional prosthetic system. The Biofunctional Prosthetic System brand denture includes a comprehensive technique for impressions, record taking, tooth placement, fabrication and processing. The advantage of this technique is to provide patients with optimal form, function, and aesthetics in complete dentures. This system is based on a team effort and systematic approach to removable prosthetic treatment.
Prevention of postoperative tooth sensitivity: a preliminary clinical trial
Authors: SOBRAL M. A. P. , GARONE‐NETTO N. , LUZ M. A. A. C. , SANTOS A. P.
Published: August 2005

summary  The purpose of this study was to evaluate clinically the effects of pre‐treatments with a 35% hydroxyethyl metacrylate/5% glutaraldehyde dentine desensitizer (Gluma Desensitizer) and a 2% chlorexidine‐based cavity disinfectant (Cav‐Clean) on postoperative sensitivity. Three premolar teeth with no pain symptoms were selected from each one of 17 patients, totalling 51 teeth, for which Class II restoration using a composite was indicated. Each one of the three premolar teeth of the same patient was submitted to a different treatment. After acid etching, only a dental adhesive was applied to the first tooth, which served as the control. Gluma Desensitizer dentinal desensitizer was applied to the second premolar tooth prior to applying the dental adhesive. Cav‐Clean cavity disinfectant was used on the third premolar tooth before applying the dental adhesive. Only one tooth was restored per session, and all premolar teeth were restored with a condensable composite, according to current restoration technique guidelines. Sensitivity to different stimuli (cold, heat, sweet and dental floss) was assessed on Day 1, Day 4 and Day 7 by questionnaire following restorative procedures. The results of this clinical research showed that, as far as the investigated stimuli and postoperative course are concerned, there was no statistically significant difference in the three different treatments (P > 0·05). Postoperative sensitivity resulting from Class II restorations using composite resin cannot be completely eliminated with the prior use of a dentinal desensitizer or a cavity disinfectant. In day‐to‐day clinical treatment, postoperative sensitivity may possibly be related to the technique employed.
Association between diet, social resources and oral health related quality of life in edentulous patients
Authors: ALLEN P. F.
Published: August 2005

summary  To assess whether there was an association between diet, oral health related quality of life and social resources in a population of older edentulous adults, and, to assess the impact of provision of new complete replacement dentures. This study was carried out at Cork University Dental Hospital in Ireland. In this prospective clinical study, 35 edentulous adults who requested new complete dentures completed pre‐treatment questionnaires which included validated oral health status, social resources and nutritional assessment questionnaires. New dentures were provided and the impact of treatment on oral health related quality of life, diet and ability to chew food was assessed. Satisfaction with dentures and oral health related quality of life improved following provision of new dentures. However, food choice remained similar to pre‐treatment choice, and subjects were rated as medium risk for poor nutritional status on the Mini Nutritional Assessment (MNA) score. Oral health related quality of life and diet were not correlated. Three quarters of the sample felt they had no nutritional problems. However, approximately 70% reported that they had changed their food choices because of dental problems and that financial cost was a barrier to dental treatment. Food selection among the group studied was not ideal, and not improved by the provision of new dentures. There was no association between diet and oral health related quality of life. Further research is needed to improve our understanding of the relationship between oral health and diet.
Midfacial and mandibular morphometry of children with Class II and Class III malocclusions
Authors: CHANG H. P. , LIN H. C. , LIU P. H. , CHANG C. H.
Published: August 2005

summary There is insufficient evidence in conventional cephalometric analysis of the actual sites of putative maxillofacial change in Class II and Class III malocclusions. The purpose of this study was to provide more information about the morphological characteristics of the midfacial complex and mandible in children with Class II or III malocclusions. Seventy children with Class II, division 1 malocclusion and 70 children with Class III malocclusion were compared with 70 children with normal occlusion. This study was conducted to carry out geometric morphometric assessments to localize alterations using Procrustes analysis and thin‐plate spline analysis. Procrustes analysis indicated the midfacial and mandibular morphologies differed between normal occlusion subjects and subjects with Class II or Class III malocclusion (P < 0·0001). The deformations in subjects with Class II malocclusion may represent a developmental elongation of the palatomaxillary complex and a shortening of the mandible anteroposteriorly, which leads to the appearance of a protruding midface and retruding mandibular profile. In contrast, the deformations in subjects with Class III malocclusion may represent a developmental shortening of the palatomaxillary complex and elongation of the mandible anteroposteriorly, which leads to the appearance of a retrognathic midface and prognathic mandibular profile.
Ethnic Variations of IL‐10 Polymorphisms in a Sami and Norwegian Population
Authors: Torkildsen Ø. , Utsi E. , Harbo H. F. , Mellgren S. I. , Vedeler C. A. , Myhr K.‐M.
Published: August 2005

Interleukin‐10 (IL‐10) production is genetically determined and influenced by different polymorphisms in the promoter region of IL‐10. These polymorphisms may contribute to the risk and clinical outcome of various infectious and immunological‐related diseases. The Samis are the aboriginal inhabitants of Norway and Fennoscandinavia and are ethnically different from the Norwegians. Different distribution of various immune‐related diseases among the Samis compared with Norwegians have been reported. This is the first study to evaluate the distribution of IL‐10 polymorphisms in the Sami population. Two hundred healthy Samis were genotyped for polymorphisms in the promoter region of IL‐10 at region −1082 (G/A), −819 (T/C) and −592 (A/C). The allele frequencies, genotypes and haplotypes were compared with 187 healthy Norwegians. A significantly higher number of the Samis than the Norwegians had the ATA/ATA genotype, whereas the Norwegians displayed a higher frequency of the GCC/GCC genotype (P = 0.0057). There was a significant difference in haplotypes in the two populations with a P = 0.0024. These findings may be important for the distribution and clinical outcome of various infectious and immune‐related disorders in the two populations.
Signal Pathway of Cytokines Produced by Reactive Oxygen Species Generated from Phorbol Myristate Acetate‐Stimulated HMC‐1 Cells
Authors: Kim J. Y. , Ro J. Y.
Published: August 2005

The relationship of cytokine production and reactive oxygen species (ROS) generated in mast cells has not been reported yet. This study aimed to examine the signal pathway in the production of cytokines [interleukin‐8 (IL‐8) and tumour necrosis factor‐α (TNF‐α)] by ROS generated from phorbol myristate acetate (PMA)‐stimulated human mast cell line‐1 cells (HMC‐1). HMC‐1 cells were stimulated with 25 ng/ml of PMA. The ROS generation and production of cytokines (IL‐8 and TNF‐α) were measured by fluorescence‐activated cell sorter and enzyme‐linked immunosorbent assay method, respectively. Phosphorylation of mitogen‐activated protein kinase family (extracellular signal‐regulated kinase, p38 and c‐Jun N‐terminal kinase) was detected by the Western blotting method. The expression of cytokine's mRNA was measured by reverse transcriptase – polymerase chain reaction, and the DNA‐binding activity of the transcription factors [nuclear factor‐κB (NF‐κB) and activator protein‐1] was detected by electrophoretic mobility shift assay. PMA‐stimulated HMC‐1 cells immediately generated ROS, and the generated ROS was inhibited by 1,3‐dimethyl‐2‐thiourea (DMTU), but partially inhibited by catalase orN‐acetyl‐l‐cysteine. The production of cytokines in PMA‐stimulated HMC‐1 cells reached the maximum at 3–5 h and was inhibited by DMTU and specific kinase inhibitor for p38, SB203580. DMTU and SB203580 also inhibited the expressed cytokine's mRNA level and the increased DNA‐binding activity of transcription factors, NF‐κB in PMA‐stimulated HMC‐1 cells. These data suggest that intracellular ROS generated from PMA‐stimulated HMC‐1 cells contributes to the production of inflammatory cytokines via p38 kinase/NF‐κB.
Phenotypic Study of Peripheral Blood Lymphocytes and Humoral Immune Response in Helicobacter pylori Infection According to Age
Authors: Soares T. F. , Rocha G. A. , Rocha A. M. C. , Corrêa‐Oliveira R. , Martins‐Filho O. A. , Carvalho A. S. T. , Bittencourt P. , Oliveira C. A. , Faria A. M. C. , Queiroz D. M. M.
Published: August 2005

There are differences between children and adults in certain aspects of the Helicobacter pylori (HP) infection, among them the lower titre of IgG antibodies anti‐HP in the former group. Thus, we investigated by means of flow cytometry CD4+/CD3+ (CD4+T), CD8+/CD3+ (CD8+T) and CD19+/CD3– (B) cells, activation/co‐stimulatory markers (CD4+/HLA‐DR+, CD4+/CD28+, CD8+/HLA‐DR+ and CD8+/CD28+) and by means of ELISA IgG anti‐HP antibodies in the peripheral blood from HP‐positive and ‐negative children and adults. An increased CD4+/CD28+ and CD8+/CD28+ percentage and number of CD4+/CD3+ cells were seen in infected adults. Conversely, no difference was observed between infected and noninfected children, but when they were stratified by age, an increased CD4+/CD28+ cell percentage was seen in the HP‐positive group older than 10 years. The mean level of IgG anti‐HP was lower in younger infected children, increased with age and correlated with CD4+ cells. Our data suggest that the immune response to HP infection vary according to the age. Low percentage of activated CD4+ cell may contribute to the lower level of serum IgG anti‐HP observed in younger infected children. In addition, the CD4+ cell participation during the infection seems to begin after 10 years old, when the immune response becomes similar to that seen in adults.
Allergen Challenge Alters Intracellular Cytokine Expression
Authors: Muratov V. , Barck C. , Bylin G. , Källström E. , Halldén G. , Van Hage M. , Elvin K. , Lundahl J.
Published: August 2005

The pathophysiology of asthma is complex and engages cascades of events in the cytokine network. We, therefore, investigated the impact of bronchial allergen challenge in humans on the cytokine profile of circulating lymphocytes. Peripheral blood samples from 10 patients with allergic asthma were collected before and 24 h after allergen provocation. Patients who mounted a late‐phase reaction were designated dual responders opposite to single responders. Whole blood cells were stimulated by mitogen and intracellular interleukin (IL)‐4 and interferon (IFN)‐γ were detected by flow cytometry. The allergen challenge induced a decrease in IL‐4+CD4+ cells in the patients (P = 0.05), and a significant decrease (P < 0.05) in IFN‐γ+CD4+ cells was noted in single, but not dual, responders. In addition, there was a significant difference (P < 0.01) with respect to the changes in the IFN‐γ+CD4+ cells comparing dual and single responders. No corresponding changes were observed in CD8+ cells. The data suggest a possible on‐going traffic of IFN‐γ and IL‐4+CD4+ lymphocytes into the bronchial mucosa in relation to an allergen challenge and generate the hypothesis that a difference exists between single and dual responders in this respect. Because the CD4+IFN‐γ‐producing cells have the capacity to downregulate the T‐helper type 2 response, a reduced capacity in this aspect might contribute to the pathophysiology in dual responders.
Requisite Role for Complement C5 and the C5a Receptor in Granulomatous Response to Mycobacterial Glycolipid Trehalose 6,6′‐Dimycolate
Authors: Borders C. W. , Courtney A. , Ronen K. , Pilar Laborde‐Lahoz M. , Guidry T. V. , Hwang S.‐A. , Olsen M. , Hunter R. L. , Hollmann T. J. , Wetsel R. A. , Actor J. K.
Published: August 2005

The development of pulmonary granulomatous lesions during mycobacterial infection is a complex phenomenon, in part caused by responses elicited towards the surface glycolipid trehalose 6,6′‐dimycolate (TDM; cord factor). The molecular mechanisms underlying granuloma formation following challenge with TDM are not yet completely understood. The present study defines pathologic differences in acute response to Mycobacterium tuberculosis TDM in C57BL/6 mice and mice lacking the C5a receptor (C5aR–/–). Mice were intravenously injected with TDM prepared in water‐in‐oil‐in‐water emulsion and examined for histologic response and changes in proinflammatory cytokines and chemokines in lung tissue. Control C5a receptor‐sufficient mice demonstrated a granulomatous response that peaked between days 4 and 7. Increased production of macrophage inflammatory protein‐1 alpha (MIP‐1α), interleukin‐1β (IL‐1β) and CXC chemokine KC (CXCL1) correlated with development of granulomas, along with modest change in tumor necrosis factor‐alpha (TNF‐α). In contrast, the C5aR–/– mice revealed markedly exacerbated inflammatory response. The receptor‐deficient mice also demonstrated a lack of coherent granulomatous response, with severe oedema present and instances of lymphocytic cuffing around pulmonary vessels. Lung weight index was increased in the C5aR–/– mice, correlating with increased MIP‐1α, KC, IL‐1β and TNF‐α over that identified in the congenic C5aR‐sufficient controls. Correlate experiments performed in C5‐deficient (B10.D2‐H2d H2‐T18c Hco/oSnJ) mice revealed similar results, leading to the conclusion that C5 plays a significant role in mediation of chemotactic and activation events that are the basis for maturation of granulomatous responses to TDM.
Clearance of Chlamydia pneumoniae Infection in H‐2 Class I–/– Human Leucocyte Antigen‐A2.1 Monochain Transgenic Mice
Authors: Tammiruusu A. , Haveri A. , Pascolo S. , Lahesmaa R. , Stevanovic S. , Rammensee H.‐G. , Sarvas M. , Puolakkainen M. , Vuola J. M.
Published: August 2005

CD8+ T cells have been suggested to play an important role in protective immunity against pulmonary Chlamydia pneumoniae infection in mice. Moreover, several classical major histocompatibility complex class I – restricted cytotoxic CD8+ T lymphocytes (CTL) specific for C. pneumoniae– derived peptides have been identified. Here, we studied the outcome of C. pneumoniae infection in human leucocyte antigen (HLA)‐A2.1 transgenic mice (HHD mice) that are only able to express a classical human class I molecule (HLA‐A2.1). C. pneumoniae infection was self‐restricted in HHD mice which were able to develop specific immune responses and a protective immunity against a subsequent rechallenge in a manner comparable to wildtype mice. Furthermore, accumulation of functional and C. pneumoniae‐specific T cells to the site of infection was detected after challenge. Antigen processing and HLA‐A2.1‐dependent presentation was studied by immunizing the HHD mice with chlamydial outer protein N (CopN). Isolation of a peptide‐specific CTL line from the CopN‐immunized mice suggests that the HLA‐A2.1 molecule can support the development of CTL response against a chlamydial protein in mice. These findings suggest that the transgenic mouse model can be used for further characterization of the HLA‐A2.1‐restricted CD8+ T‐cell response during C. pneumoniae infection and for identification of CD8 epitopes from chlamydial antigens.
Evidence for Involvement of p59fyn in Fasting‐Induced Thymic Involution
Authors: Nishio H. , Takase I. , Fukunishi S. , Takagi T. , Tamura A. , Miyazaki T. , Suzuki K.
Published: August 2005

p59fyn, a member of the src‐family protein tyrosine kinase, is expressed abundantly in thymus. We examined the possible involvement of p59fyn in thymic involution induced by a fasting stress in Fyn–/– mice. An acute 48 h fast resulted in severe atrophy of the thymus and a marked decrease of the total thymocyte number with depletion of the CD4+CD8+[double positive (DP)] population in Fyn+/+ (control) mice. A remarkable increase in terminal deoxynucleotidyl transferase‐mediated dUTP‐biotin nick end labelling‐positive signals was detected in the fasted group of control mice. However, these findings were not observed in Fyn–/– mice. Interestingly, MRL/MPJ‐lpr/lpr, a Fas‐deficient model animal, also showed no significant decrease of DP cell numbers in the fasted group. p59fyn is known to interact with Fas signalling, and these findings suggest that p59fyn is involved in fasting‐induced thymic involution, raising the possibility that Fas/p59fyn‐mediated signalling may, at least partially, be associated with the phenomenon.
Intrahepatic CD4+ T‐Cell Apoptosis is Related to METAVIR Score in Patients With Chronic Hepatitis C Virus
Authors: Roger P.‐M. , Chaillou S. , Breittmayer J.‐P. , Dahman M. , St. Paul M.‐C. , Chevallier P. , Benzaken S. , Ticchioni M. , Bernard A. , Dellamonica P. , Tran A.
Published: August 2005

Hepatitis C virus (HCV) infection leads to liver injury, which is thought to be immune‐mediated. Apoptosis of hepatic T cells could influence histological damage. We quantified peripheral and intrahepatic T‐cell apoptosis in 28 patients with chronic hepatitis C by using cytofluorometric techniques. METAVIR score and HCV plasma viral load were determined. Six liver biopsies, obtained from controls without chronic hepatitis during hepatobiliary surgery, served as controls. In patients, liver T‐cell apoptosis was upregulated compared to peripheral T cells: 35 versus 7% for CD4+ and 56 versus 13% for CD8+ T cells (P < 0.001). Liver T‐cell apoptosis levels from patients were increased compared to controls for both CD4+ (P = 0.041) and CD8+ T cells (P = 0.007). Nine patients exhibiting METAVIR scores A and F ≤1 showed higher intrahepatic CD4+ T‐cell apoptosis compared to the 19 patients with a higher METAVIR score (P = 0.001) and both histological activity and fibrosis were related to apoptosis level. There was also an inverse relationship between the level of intrahepatic CD8+ T‐cell apoptosis and serum transaminase activity (P = 0.023). Our study shows immune compartmentalization, suggesting that the study of peripheral blood lymphocytes may not be fully relevant to the pathophysiology of HCV hepatitis, and that the severity of liver injury is inversely correlated with intrahepatic CD4+ T‐cell apoptosis.
Neurotrophic Factors and Clinical Recovery in Relapsing‐Remitting Multiple Sclerosis
Authors: Caggiula M. , Batocchi A. P. , Frisullo G. , Angelucci F. , Patanella A. K. , Sancricca C. , Nociti V. , Tonali P. A. , Mirabella M.
Published: August 2005

Pathogenic autoimmune cells are demonstrated to be able to produce neurotrophic factors during acute phase of multiple sclerosis (MS). In this study, we determined the production of various neurotrophins [brain‐derived neurotrophic factor (BDNF), nerve growth factor (NGF), glial cell line‐derived neurotrophic factor (GDNF), neurotrophin 3 (NT3) and neurotrophin 4 (NT4)] and some pro‐inflammatory cytokines [tumour necrosis factor‐α (TNF‐α) and interferon‐γ (IFN‐γ)] by unstimulated peripheral blood mononuclear cells (PBMC) in 21 relapsing‐remitting MS patients during different phases of disease (stable, relapse and post‐relapse). During acute phase of disease, we detected a considerable increase of BDNF, TNF‐α and IFN‐γ production, while significantly higher levels of GDNF, NGF, NT3 and NT4 were found in post‐relapse phase. When neurotrophin production was correlated with clinical outcome (complete or partial recovery from new symptoms), we found a significantly higher BDNF production in relapse phase followed by increased GDNF, NGF, NT3 and NT4 levels during post‐relapse phase in subjects with complete remission only. During relapse phase, we detected a significant increase of pro‐inflammatory cytokines, that was more evident in patients with partial recovery. The neuroprotective potential of immune cells seems to be inversely correlated with disease duration and with the age of patients.
Immunization by Arg‐gingipain A DNA vaccine protects mice against an invasive Porphyromonas gingivalis infection through regulation of interferon‐γ production
Authors: Yonezawa H. , Kato T. , Kuramitsu H. K. , Okuda K. , Ishihara K.
Published: August 2005

We previously demonstrated that a Porphyromonas gingivalis rgpA DNA vaccine induced protective immune responses against P. gingivalis infection in mice (Yonezawa et al. Infect Immun 2001: 69: 2858–2864). In the present study, reduction in lethality against infection by lethal doses of P. gingivalis was observed in the rgpA DNA vaccine‐immunized mice. Cytokine levels in the mouse model with nonlethal doses of infection by P. gingivalis were evaluated to analyze the mechanism of protection by immunization with the rgpA DNA vaccine. After nonlethal challenge with invasive P. gingivalis W50, production of interleukin (IL)‐2, IL‐4, IL‐5 and IL‐12 was elevated; however, interferon (IFN)‐γ was lower in the serum of the DNA vaccine‐immunized mice than in the serum of nonimmunized mice. The regulation of IFN‐γ production elicited by immunization with the rgpA DNA vaccine may play a significant role in protection against P. gingivalis infection in mice.
T‐cell independent production of salivary secretory IgA after hematopoietic stem cell transplantation in children
Authors: Steinbrenner M. , Häfer R. , Gruhn B. , Müller A. , Fuchs D. , Hermann J. , Zintl F.
Published: August 2005

This study examined the recovery of secretory IgA (S‐IgA) in saliva after hematopoietic stem cell transplantation (HSCT) in 35 children and young people between the ages of 3 and 27 years (mean = 13.6), and compared this recovery with that of serum immunologic constituents. Reference values for human salivary S‐IgA in saliva were obtained from 77 healthy control subjects between the ages of 7 and 25 years (mean = 11.4). In the 35 patients, a nadir of secretory IgA concentrations in saliva (S‐IgA) was observed between the 3rd and the 4th month, and a return to normal values 1 year after HSCT. Serum IgA concentrations reached their nadir in the 6th month, and normalized in the 18 months after HSCT. The recovery of T‐helper cells (CD4+/3+) was also delayed to beyond 18 months. We found a significant correlation between the reconstitution pattern of S‐IgA and that of T‐helper lymphocytes, but no correlation was found between the post‐transplant evolutions of S‐IgA and serum IgA, or between S‐IgA and T‐helper cells. The recovery of S‐IgA was more rapid than that of serum IgA and appeared to be T‐helper cell independent.
Detection of bacteria in endodontic samples by polymerase chain reaction assays and association with defined clinical signs in Italian patients
Authors: Foschi F. , Cavrini F. , Montebugnoli L. , Stashenko P. , Sambri V. , Prati C.
Published: August 2005

Background/aims:  The presence of selected bacteria (Enterococcus faecalis, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, Treponema denticola) in infected root canals was studied using polymerase chain reaction (PCR) assays, and the association of bacteria with clinical signs of endodontic disease was assessed. The null hypothesis, that no difference could be observed between clinical signs of apical periodontitis and a specific bacterial strain, was tested.

Methods:  Microbial samples were obtained from 62 teeth in 54 patients with endodontic disease. For each tooth, clinical data including patient symptoms were collected. Teeth were categorized by diagnosis as having acute apical periodontitis (AAP, teeth with clinical symptoms but no periapical radiolucency, n = 22), chronic apical periodontitis (CAP, teeth with radiolucency but no clinical symptoms, n = 15) or exacerbated apical periodontitis (EAP, teeth with symptoms and radiolucency, n = 25). Seventy‐one percent of cases were primary endodontic infections, and 29% were recurrent (‘secondary’) endodontic infections (failing cases). PCR assays were used to detect the presence of the selected bacteria.

Results:  T. denticola and E. faecalis were each detected in 15 of 62 samples (24%), P. gingivalis in 8 samples (13%), P. intermedia in 5 samples (8%), and T. forsythensis in 4 samples (7%). T. denticola was detected in 56% of teeth with EAP. E. faecalis was found in 60% of teeth with CAP and in 72% of teeth with secondary infection. Statistical analysis demonstrated an association of CAP and secondary endodontic infection with the presence of E. faecalis. (P < 0.01). EAP was associated with the presence of T. denticola (P < 0.01).

Conclusion:  T. denticola was associated with symptomatic endodontic disease in the presence of apical bone resorption. E. faecalis was associated with treatment failures. We suggest that these species may play critical roles in endodontic pathology.
Bacterial internalization in periodontitis
Authors: Vitkov L. , Krautgartner W. D. , Hannig M.
Published: August 2005

Background:  Bacterial invasion of host epithelial cells plays an important role in the pathogenesis of periodontitis; however, the exact mechanism of the invasion has not been investigated.

Methods:  Pocket epithelium biopsies in periodontitis were analysed via scanning and transmission electron microscopy using ultra‐histochemical staining with ruthenium red for glycocalyx visualization.

Results:  We demonstrated that oral bacteria adhered via fimbriae‐mediated adhesion only. The bacterial internalization in periodontitis was marked by the hallmark of the fimbriae‐induced zipper mechanism – the phagocytic cup formation – but we found no sign of the trigger mechanism of internalization. In addition, we frequently observed apoptosis in the phagocytizing epithelial cells.

Conclusion:  Fimbriae‐mediated adhesion is a prerequisite for bacterial invasion in periodontitis. This occurs by the fimbriae‐induced zipper mechanism of internalization. As internalization induces apoptosis, the subsequent exfoliation might play a significant role in the clearance of periodontal pathogens.
Cardiac glands hyperplastic polyp of the stomach
Authors: NAGATA SHINJI , TANAKA SHINJI , ITO MASANORI , YOSHIHARA MASAHARU , HARUMA KEN , CHAYAMA KAZUAKI
Published: August 2005

Abstract  Reported herein is a very rare polyp in the gastric cardia of a 49‐year‐old man. He was referred because of a polyp detected by upper gastrointestinal examination in an affiliated hospital. Endoscopic examination revealed a polyp‐like submucosal tumor. Endoscopic ultrasonography revealed minute cystic dilatations and thickening of the submucosal layer. Accordingly, a preliminary diagnosis of cardiac gland hyperplasia was made. The lesion was removed successfully by snare polypectomy. Observed macroscopically, the polyp was 30 mm in diameter and covered with normal gastric mucosa. Examined histologically, the polyp comprised a hyperplastic submucosal cardiac gland.
Selective reduction of anti‐Helicobacter pylori IgG subclass antibody in gastric carcinoma
Authors: REN ZHIGANG , BORODY TOM , PANG GERALD , LI LIANG‐CHEN , DUNKLEY MARGARET , CLANCY ROBERT
Published: August 2005

Background: Epidemiological studies have demonstrated strong links between Helicobacter pylori infection and gastric adenocarcinoma. Recent studies suggest that cell‐mediated immunity influences the outcome of infection, including the development of gastric adenocarcinoma. The T‐cell response can be characterized in terms of the secreted cytokine profile, which in turn influences the B‐cell response including the balance of IgG subclass antibody.

Methods: Serum anti‐H. pylori IgG, IgG1 and IgG2 antibodies were studied by ELISA in subjects with benign gastric diseases, gastric dysplasia and gastric adenocarcinoma.

Results: The distribution patterns of IgG subclass anti‐H. pylori antibody varies significantly between H. pylori‐linked benign and malignant disease in subjects infected with H. pylori. Significantly lower IgG2 levels were found in subjects with gastric adenocarcinoma compared with those with reflux esophagitis, chronic gastritis, gastric ulcer, and peptic ulcer, while IgG1 antibody remained at similar levels in both benign and malignant disease. A limited study of seropositive subjects with premalignant change was consistent with the fall in IgG2 antibody pre‐dating malignant change, although pre‐eradication results are needed to validate these data.

Conclusions: These studies indicate that subjects with low levels of IgG2 anti‐H. pylori antibody are at risk of gastric adenocarcinoma, and that the previously described linkage between gastric adenocarcinoma and low total IgG antibody does not simply reflect reduced gastric colonization. The diagnostic value of this assay for pre‐endoscopy screening is attractive.
No correlation between clinical symptoms and Blastocystis hominis in immunocompetent individuals
Authors: LEDER KARIN , HELLARD MARGARET E , SINCLAIR MARTHA I , FAIRLEY CHRISTOPHER K , WOLFE RORY
Published: August 2005

Background and Aim: Previous reports regarding the clinical significance and pathogenicity of Blastocystis hominis have been contradictory. The aim of this study was to examine the association between Blastocystis and gastrointestinal symptoms in immunocompetent individuals.

Methods: We monitored over 2800 healthy people for a period of 15 months, and took stool specimens during both asymptomatic periods and during periods of gastrointestinal symptoms.

Results: After exclusion of individuals who had simultaneous identification of other fecal pathogens, we compared the proportions of asymptomatic versus symptomatic individuals positive for Blastocystis and found no significant difference (P = 0.5). Symptom status did not correlate with parasite abundance. We found that some individuals were likely to have Blastocystis detected during both asymptomatic and symptomatic periods, possibly suggesting carriage of the organism.

Conclusion: In conclusion, we found no correlation between clinical symptoms and the presence or absence of Blastocystis among this healthy cohort.