bluuebunny/crossref_metadata_2025 huggingface dataset:
Administration of exogenous interleukin‐18 and interleukin‐12 prevents the induction of oral tolerance
Authors: Eaton Alfred D. , Xu Damo , Garside Paul
Published: March 2003

Interleukin‐18 (IL‐18), a pro‐inflammatory member of the IL‐1 family, has been associated with autoimmunity and allergic disease. This type of pathology is thought to be the result of a defect in immunological tolerance and is often observed in inflammatory disorders of the gut such as coeliac disease, Crohn's disease and ulcerative colitis. IL‐18 has been implicated in a number of mucosal immune disorders, where it synergizes with IL‐12 to induce the production of interferon‐γ (IFN‐γ). We have therefore investigated the effects of IL‐18 and IL‐12 administration on the induction of oral tolerance to ovalbumin. The suppression of specific Ig G2a production, delayed‐type hypersensitivity responses and IFN‐γ production by antigen‐specific T cells were all abrogated by the presence of exogenous IL‐12 and IL‐18, suggesting that oral tolerance was broken. The expression of the co‐stimulatory molecule CD80 on dendritic cells was also shown to be increased by this combination of cytokines. As dendritic cells are thought to be of major importance in the induction of tolerance, this suggests a mechanism by which tolerance to mucosal antigens may be broken in vivo.
The outcome of T‐cell costimulation through intercellular adhesion molecule‐1 differs from costimulation through leucocyte function‐associated antigen‐1
Authors: Kohlmeier Jacob E. , Rumsey Lisa M. , Chan Marcia A. , Benedict Stephen H.
Published: March 2003

Optimal T‐cell activation requires both an antigen‐specific and a costimulatory signal. The outcome of T‐cell activation can be influenced by the nature of the costimulatory signal the T cell receives. We recently demonstrated the ability of stimulation through intercellular adhesion molecule‐1 (ICAM‐1), resident on the T‐cell surface, to provide a second signal for T‐cell activation, and have extended that work here to begin an examination of the functional outcome of this set of signals. Costimulation through ICAM‐1 resulted in a greater percentage of cells having undergone more than three divisions when compared to costimulation through leucocyte function‐associated antigen‐1 (LFA‐1). Costimulation through ICAM‐1 also had an effect similar to costimulation through CD28 in its ability to down‐regulate the cyclin dependent kinase inhibitor p27kip1. Costimulation through ICAM‐1 provided greater protection from apoptosis than costimulation through LFA‐1, especially in cells having divided more than three times. This was supported by the ability of costimulation through ICAM‐1 to up‐regulate the anti‐apoptotic protein Bcl‐2. Finally, costimulation through ICAM‐1 or CD28 produced a greater number of T cells with a memory phenotype than costimulation through LFA‐1.
Cloning of the complete rat immunoglobulin δ gene: evolutionary implications
Authors: Zhao Yaofeng , Hammarström Lennart
Published: March 2003

The recent discovery of a Cδ encoding gene in artiodactyls has raised questions regarding the evolution of the gene. In the present study, we have analysed the complete rat Cδ gene both at the cDNA and genomic levels, showing that the rat Cδ gene is structurally similar to the corresponding mouse gene. Analysis of the rat immunoglobulin D heavy chain cDNA tail sequences, revealed two transcripts for the secreted form with varying sizes of their 3′ untranslated region (UTR), resulting from usage of two different poly(A) addition signals. Furthermore, a membrane‐bound form encoding transcript, possessing a long 3′ UTR, was also observed. Phylogenetic analysis supports that the Cδ gene appeared early in the evolution of vertebrates, and it was probably duplicated from the Cµ gene more than 400 million years ago.
On the security of open source software
Authors: Payne Christian
Published: March 2003

Abstract With the rising popularity of so‐called ‘open source’ software there has been increasing interest in both its various benefits and disadvantages. In particular, despite its prominent use in providing many aspects of the Internet's basic infrastructure, many still question the suitability of such software for the commerce‐oriented Internet of the future. This paper evaluates the suitability of open source software with respect to one of the key attributes that tomorrow's Internet will require, namely security. It seeks to present a variety of arguments that have been made, both for and against open source security and analyses in relation to empirical evidence of system security from a previous study. The results represent preliminary quantitative evidence concerning the security issues surrounding the use and development of open source software, in particular relative to traditional proprietary software.
Intangible benefits valuation in ERP projects
Authors: Murphy Kenneth E , Simon Steven John
Published: March 2003

The development, implementation and ownership of information systems, especially large‐scale systems such as enterprise resource planning (ERP), has become progressively longer in duration and more cost intensive. As a result, IS managers are being required to justify projects financially based on their return. Historically, information systems have been difficult to quantify in monetary terms because of the intangible nature of many of the derived benefits, e.g. improved customer service. Using the case study methodology, this paper examines an attempt by a large computer manufacturer to incorporate intangibles into traditional cost–benefit analysis in an ERP project. The paper reviews the importance of intangibles, lists intangible benefits that are important in ERP projects and demonstrates the use of a scheme through which they can be incorporated into traditional evaluation techniques.
Germline transformation of Drosophila melanogaster with the piggyBac transposon vector
Authors: Handler A. M. , Harrell Ii R. A.
Published: March 2003

Germline transformation of Drosophila melanogaster was attempted with the piggyBac gene‐transfer system from the cabbage looper moth, Trichoplusia ni. Using a self‐regulated transposase helper and a white marked vector, a transformation frequency of 1–3% per fertile G0 was obtained, similar to that previously achieved in the medfly. Use of an hsp70‐regulated helper increased this frequency more than eight‐fold. Transformation with a vector marked with white and green fluorescent protein (GFP) under polyubiquitin–nuclear localizing sequence regulation yielded seventy G1 transformants which all expressed GFP, but only twenty‐seven of these expressed eye pigmentation that would have allowed their selection based on white+ expression. PiggyBac transformation in two distantly related dipteran species and efficient expression of the gfp marker supports the potential use of this system in other dipterans, and perhaps insects in general.
Differentiation of Asian rice gall midge, Orseolia oryzae (Wood‐Mason), biotypes by sequence characterized amplified regions (SCARs)
Authors: Behura S. K. , Sahu S. C. , Rajamani S. , Devi A. , Mago R. , Nair S. , Mohan M.
Published: March 2003

We developed a polymerase chain reaction (PCR)‐based assay that distinguished five different biotypes of the Asian gall midge (Orseolia oryzae), a major insect pest of rice. A total of 400 random primers were screened using random amplified polymorphic DNAs (RAPDs). Five diagnostic PCR products were isolated, cloned, sequenced and converted to sequence characterized amplified regions (SCARs). Primers specific to these SCARs were able to amplify specific DNA fragments from genomic DNAs of five biotypes of gall midge in a multiplexed‐PCR‐based assay. The amplified DNA fragments were used as diagnostic markers to identify different biotypes of gall midge. The SCAR primers were also capable of differentiating the Asian from the African rice gall midge (Orseolia oryzivora) as well as detecting a variant of biotype 5 which caused an outbreak in Kerala, India. Unlike the use of plant host differentials and midge feeding behaviour for identifying biotypes, this assay is fast, reliable and unaffected by environmental factors.
Molecular cloning and structural analysis of 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase of the moth Agrotis ipsilon
Authors: Duportets L. , Belles X. , Rossignol F. , Couillaud F.
Published: March 2003

The enzyme 3‐hydroxy‐3‐methylglutaryl coenzyme A (HMG‐CoA) reductase, which plays a key role in isoprenoid biosynthesis, catalyses the synthesis of mevalonate from HMG‐CoA. Insects do not synthesize cholesterol de novo, rather mevalonate derivatives lead to non‐sterol isoprenoids which are essential for development and reproduction. In this paper, we describe an HMG‐CoA reductase of the moth Agrotis ipsilon and we report its expression in fat body, ovary, muscle, brain and corpora allata tissues of adult specimens. The analysis of the cDNA reveals that it encodes a polypeptide of 833 amino acids (Mr = 89785). Alignments of this HMG‐CoA reductase from A. ipsilon with the homologous sequences of other eukaryotes shows a high degree of conservation in all species studied. Parsimony analysis based on these alignments produced dendrograms congruent with the current systematic schemes. This suggests that, during eukaryote evolution, HMG‐CoA reductase diversified in parallel with taxonomic splitting.
Transformation of Stomoxys calcitrans with a Hermes gene vector
Authors: O’Brochta D. A. , Atkinson Peter W. , Lehane Michael J.
Published: March 2003

The ability of the Hermes transposable element to function as a germ line transformation vector was tested in the stable fly, Stomoxys calcitrans. Plasmid‐based transposable element mobility assays indicated moderate mobility of Hermes in this species. Germline transformants were created using a Hermes element containing the enhanced green fluorescent protein (EGFP) under the regulatory control of the promoter from Actin5C gene of Drosophila melanogaster. Approximately 4% of the fifty‐five adults that developed from the 1903 G0 embryos injected with the vector produced transgenic progeny. In the four transgenic lines established, the EGFP expression pattern was distinctly nonuniform and levels of expression were low. Promoters other than the one from the Actin5C gene of D.melanogaster should be considered for widespread, constitutive expression. All transgenic lines contained multiple (2–4) integrated Hermes elements. Hermes integration events occurred through a canonical cut‐and‐paste mechanism.
Germ line transformation of the yellow fever mosquito, Aedes aegypti, mediated by transpositional insertion of a piggyBac vector
Authors: Lobo N. F. , Hua‐Van A. , Li X. , Nolen B. M. , Fraser M. J.
Published: March 2003

Mosquito‐vectored diseases such as yellow fever and dengue fever continue to have a substantial impact on human populations world‐wide. Novel strategies for control of these mosquito vectored diseases can arise through the development of reliable systems for genetic manipulation of the insect vector. A piggyBac vector marked with the Drosophila melanogaster cinnabar (cn) gene was used to transform the white‐eyed khw strain of Aedes aegypti. Microinjection of preblastoderm embryos resulted in four families of cinnabar transformed insects. An overall transformation frequency of 4%, with a range of 0% to as high as 13% for individual experiments, was achieved when using a heat‐shock induced transposase providing helper plasmid. Southern hybridizations indicated multiple insertion events in three of four transgenic lines, while the presence of duplicated target TTAA sites at either ends of individual insertions confirmed characteristic piggyBac transposition events in these three transgenic lines. The transgenic phenotype has remained stable for more than twenty generations. The transformations effected using the piggyBac element establish the potential of this element as a germ‐line transformation vector for Aedine mosquitoes.
Molecular analysis of multiple cytochrome P450 genes from the malaria vector, Anopheles gambiae
Authors: Ranson H. , Nikou D. , Hutchinson M. , Wang X. , Roth C. W. , Hemingway J. , Collins F. H.
Published: March 2003

Cytochrome P450s are a superfamily of haemoproteins, important in the metabolism of endogenous compounds and xenobiotics. As a first step to elucidating the role of this family in insecticide resistance in the malaria mosquito, Anopheles gambiae, we have cloned and mapped multiple P450 genes. Sixteen cDNAs encoding full‐length P450s were cloned and physically mapped to the mosquito's polytene chromosomes. Fourteen of these encode putative CYP6 proteins and two encode P450s belonging to the CYP9 class. Eighteen new A. gambiae Cyp4 P450 genes were identified using degenerate PCR primers, cDNAs were detected for ten and in situ locations for thirteen members of this gene family.
Bacterial leakage versus dye leakage in obturated root canals
Authors: Barthel C. R. , Moshonov J. , Shuping G. , Òrstavik D.
Published: March 2003

Aim The aim of this study was to compare in vitro bacterial and dye leakage tests, commonly used to determine the seal of root canal fillings.

Methodology Ninety‐six single‐rooted teeth had their crowns removed at the cemento‐enamel junction and their roots instrumented to ISO size 60 within 1 mm of the apex. Three groups of 30 roots were obturated by lateral condensation using gutta‐percha and one or other of the sealers, AH26, Ketac Endo, or Roth's 801 sealer. Three roots were used as negative controls and three roots as positive controls. The roots were then exposed at their coronal end first for 38 days to soy broth containing Staphylococcusepidermidis and thereafter for 48 h to basic fuchsin. Bacterial leakage was recorded when the challenging organism could be recovered from the apical end. Dye leakage was checked by microscopy of transverse sections of the apical tip at the end of the experiment.

Results For the bacterial experiment, there was no significant difference amongst the three sealer groups. The dye experiment showed significantly greater leakage in the AH26 compared to the Ketac Endo group. No correlation between the results of the two tests could be seen.

Conclusions The results of this study suggest that the molecular size of the penetrating agent may not be the relevant parameter when attempting to determine an appropriate test for the sealability of root canal fillings.
Penetration of bacteria in bovine root dentine in vitro
Authors: Peters L. B. , Wesselink P. R. , Moorer W. R.
Published: March 2003

Peters LB, Wesselink PR, Moorer WR. Penetration of bacteria in bovine root dentine in vitro. International Endodontic Journal, 33, 28–36, 2000.

Aim  The aim of this study was to develop a test model to quantify the penetration of bacteria into dentinal tubules.

Methodology The model consisted of two compartments separated by a bovine dentine specimen with a thickness of 1.5–3.1 mm. The root cementum was removed from the root surface and the specimens were oriented in the model with the pulpal side facing the inoculated chamber of the test model. One compartment contained the test organism and the other was filled with sterile broth that was evaluated for growth of the test organism. The depth of bacterial penetration was measured in the dentine with or without a smear layer using both a histological and a quantitative recovering grinding technique, after 6 weeks of exposure to the microorganisms.

Results  E. faecalis penetrated dentine significantly deeper than A. israelii (P <0.001). After removal of the smear layer with EDTA, E. faecalis penetrated significantly deeper than in dentine pretreated with saline only (P <0.01) or with a combination of saline and sodium hypochlorite (P <0.01). Microorganisms were found in 89% of the cultured specimens and in 80% of the specimens that were evaluated with light microscopy. Total penetration through the dentine specimen and infection of the broth in the test compartment of the model occurred in only two out of 72 specimens.

Conclusion  Collection and immediate culturing of infected dentine dust and counting colony forming units (CFU) allowed an overview of the number of bacteria per sample and was more sensitive than microscopy. Removal of the smear layer enhanced bacterial penetration.
Four second molars with single roots and single canals in the same patient
Authors: Fava L. R. G. , Weinfeld I. , Fabri F. P. , Pais C. R.
Published: March 2003

Fava LRG, Weinfeld I, Fabri FP, Pais CR. Four second molars with single roots and single canals in the same patient: a case report. International Endodontic Journal, 33, 138–142 2000.

Case report Studies on canal configuration have demonstrated a substantial variation in the number of

roots and root canals in different teeth. Maxillary and mandibular molars may have three and two roots, respectively, and generally present with three or four root canals. This case describes the presence of one single root and one root canal in all second molars of the same patient.
Antimicrobial effectiveness of electro‐chemically activated water as an endodontic irrigation solution
Authors: Marais J. T. , Williams W. P.
Published: March 2003

Aim The aim of this in vitro study was to evaluate the antimicrobial effectiveness of electro‐chemically activated water (ECA) as an endodontic irrigation solution.

Methodology The root canals of 60 caries‐free, single‐rooted, adult, maxillary, anterior human teeth were instrumented and irrigated in a similar method to that used for in vivo root canal treatment. The external root surface of each tooth was sealed, maintaining the access cavities patent and the root canals were inoculated with a suspension containing four bacteria. The teeth were randomly divided into four groups (n = 15). Each group was irrigated ultrasonically with one of the following solutions: distilled water (control), NaOCl (3.5%), and ECA, the latter at pHs 7.0 and 9.0. Antimicrobial effectiveness was established directly after irrigation and again 7 days later, by counting colony‐forming units on blood agar plates and by spectrophotometric analysis.

Results Large numbers of bacteria were present in the canals of teeth irrigated with distilled water. No bacteria were observed following irrigation with NaOCl. Neither of the ECA solutions were found to be effective against all the bacteria. Although some reduction in the number of bacteria was evident in the ECA groups, this was not statistically significant (P > 0.05) when compared to sodium hypochlorite.

Conclusion Within the confines of this study ECA did not demonstrate antimicrobial effectiveness.
The use of computed tomography when comparing nickel–titanium and stainless steel files during preparation of simulated curved canals
Authors: Garip Y. , Günday M.
Published: March 2003

Aim

The aim of this study was to compare canal preparations completed with Hedstrom and K‐files of ISO size 15–40, made of nickel–titanium (Ni–Ti) and stainless steel (SS).

Methodology

Eighty simulated canals with 20° and 30° curvatures were prepared using the step‐back technique and quarter turn/pull instrument manipulation. Middle and apical level canal sections were taken using computed tomography.

Results

No significant difference was found between any of the file types at either level with respect to canal curvature (20° or 30°). At the middle level, the stainless steel files caused more enlargement toward the inner part, compared to nickel–titanium files. At the apical level, nickel–titanium canal files caused more enlargement toward the inner part, whereas more outward enlargement was caused by stainless steel instruments. No significant difference could be observed at the middle level (P > 0.05) related to the enlargement toward the outer side of the canal curvature.

Transportation at both levels was significantly less (P < 0.001) for the Ni–Ti files than the SS ones. Centring ratios of the file types at the middle level were low, but not significantly different (P > 0.05), whereas at the apical level the centring ratios were significantly higher for the Ni–Ti files (P < 0.001).

Conclusions

Ni–Ti instruments produced preparations with adequate enlargement, less transportation, and a better centring ratio.
The use of ultrasound for cleaning the surface of stainless steel and nickel–titanium endodontic instruments
Authors: Tanomaru Filho M. , Leonardo M. R. , Bonifácio K. C. , Dametto F. R. , Silva L. A. B.
Published: March 2003

Aim

The aim of this study was to evaluate the efficacy of ultrasound in cleaning the surface of stainless steel and Ni–Ti endodontic instruments.

Methodology

Twenty nickel–titanium instruments (10 Quantec files and 10 Nitiflex) and 20 stainless steel K‐files (10 Maillefer‐Dentsply and 10 Moyco Union Broach) were removed from their original packages and evaluated using a scanning electron microscope. Scores were given for the presence of residues on the surface of the instruments. The instruments were then cleaned in an ultrasonic bath containing only distilled water or detergent solution for 15 min, and re‐evaluated, using scanning electron microscopy.

Results

Before cleaning, a greater amount of metallic debris was observed on the nickel–titanium Quantec instruments (P < 0.05), when compared to those made of stainless steel. Statistical analysis showed that the use of ultrasound was effective for cleaning the instruments, regardless of the irrigating solution or the instruments type (P < 0.05).

Conclusions

The use of ultrasound proved to be an efficient method for the removal of metallic particles from the surface of stainless steel and Ni–Ti endodontic instruments.
Correlation between clinical success and apical dye penetration
Authors: Oliver C. M. , Abbott P. V.
Published: March 2003

Aim

This study was undertaken to examine whether a correlation exists between apical dye penetration and the clinical performance of root fillings.

Methodology

Apical dye penetration into 116 roots of human teeth that had been root‐filled at least 6 months prior to extraction was tested in vitro using a vacuum technique and by measuring the length of dye penetration. Endodontic treatment was classified as clinically successful or unsuccessful and results for these groups were compared using analysis of variance and the Student's t‐test. Positive and negative controls were used to test the experimental system.

Results

All controls performed as expected. Dye penetrated significantly further in unsuccessful cases although the raw data suggested little difference. Overall, dye penetrated 99.5% of the specimens, indicating that the presence of dye in the canal is a poor indicator of whether the technique or material will succeed. However, the extent of dye penetration may be related to the clinical outcome.

Conclusions

Clinically placed root canal fillings do not provide an apical seal that prevents fluid penetration. The outcome of treatment cannot be predicted from the results of apical dye leakage studies.
A laboratory study of coronal microleakage using four temporary restorative materials
Authors: Cruz E. V. , Shigetani Y. , Ishikawa K. , Kota K. , Iwaku M. , Goodis H. E.
Published: March 2003

Aim The aim of this study was to compare the sealing abilities of Fermin and Canseal with the more popular temporary coronal filling materials, Cavit and Caviton.

Methodology Standardized access cavities were prepared in 160 intact human permanent molar teeth. They were divided into five groups consisting of 32 samples. The teeth were restored using one of the temporary filling materials, namely: Fermin, Canseal at two powder to liquid ratios, Caviton and Cavit. Thermal cycling and/or load cycling were applied on the samples. Assessment of microleakage utilized methylene blue dye penetration. Grading of the microleakage pattern was from 1 to 3, with 3 providing the best seal. Results were analyzed using two‐way anova and by Fisher’s PLSD post hoc test (P < 0.05).

Result Microleakage along Fermin, Caviton and Cavit samples did not go beyond Leakage Grade 2. Dye penetration into these materials was noted. This was not observed in the two groups of Canseal tested. However, the two groups of Canseal exhibited total leakage notably after being subjected to thermal cycling. There was a statistically significant difference in the microleakage scores obtained between the materials and conditions tested (P < 0.0001).

Conclusion Fermin was found to exhibit the best seal amongst the four materials tested followed by Caviton, and Cavit. Thermal cycling influenced the seal of certain types of temporary filling materials more than load cycling.
Higher thyroid hormone levels in neonatal life result in reduced testis volume in postpubertal bulls
Authors: MAJDIC  , SNOJ  , HORVAT  , MRKUN  , KOSEC  , CESTNIK
Published: March 2003

Thyroid hormones appear to determine adult testis size in rodents by regulating the period of Sertoli cell proliferation in the neonatal period. In the present study, the correlation between neonatal thyroid hormone levels (T3 and thyroxin, T4) and post‐pubertal testis size in Simental bulls was examined. T3 and T4 levels were measured in blood plasma from 35 calves immediately after their arrival at the AI centre at age 3–6 months. Testis size (height and width) was measured at 12 months of age in the same live animals. A significant negative correlation (r = −0.55; p ≤ 0.001) was found between T4 and calculated testicular volume using either the Pearson correlation test or linear regression analysis, while the levels of T3 and testis volume showed a negative correlation, although this did not reach statistical significance (r = −0.20, p ≤ 0.05). The results of this study suggest, therefore, that neonatal thyroid hormone levels might have the same effect on testicular size in cattle as they do in rodents.
Dazl protein expression in adult rat testis is up‐regulated at meiosis and not hormonally regulated
Authors: Rocchietti‐March M. , Weinbauer G. F. , Page D. C. , Nieschlag E. , Gromoll J.
Published: March 2003

The Y‐chromosomal DAZ (deleted in azoospermia) gene and the autosomal Dazl (deleted in azoospermia‐like) gene are two crucial factors for the achievement and maintenance of spermatogenesis. Whereas Y‐chromosomal DAZ is present in certain primates, it is lacking in rodents and other species. We have investigated the expression of Dazl protein during spermatogenesis in the adult rat testis using immunohistochemistry. Dazl immunoreactivity was found predominantly in the cytosol of primary pachytene spermatocytes. A weaker but clearly detectable signal was present in intermediate and B spermatogonia and in early spermatocytes from preleptotene to zygotene. The highest expression patterns were observed between stages IV and VIII during the spermatogenic cycle when spermatocytes prepare for the first meiotic division. Specific staining could also be observed in step 11–19 elongating spermatids in the acrosome region.

Treatment for 42 days with a potent GnRH‐antagonist abolished gonadotrophin secretion and led to a regressed testis, lacking most of the advanced germ cell types such as spermatids but still bearing spermatogonia and spermatocytes. No difference in staining pattern for Dazl protein was observed in GnRH antagonist‐treated rats despite the lack of gonadotrophins and substantial impairment of the spermatogenic process, indicating that Dazl expression is clearly hormone‐independent.

The localization and level of Dazl expression suggests an important role in the regulation of the first meiotic stages of spermatogenesis. The hormone independent onset of expression points to an autonomous cell‐cycle event in which Dazl seems to be essential for the entry into meiosis. The presence of Dazl in the acrosome region of elongating spermatids might reflect an unknown role of Dazl as a morphogenetic factor during spermiogenesis.
Sperm antigens recognized by antisperm antibodies present in sera of infertile adults and prepubertal boys with testicular failure
Authors: DomagaŁa Alina , Kamieniczna Marzena , Kurpisz Maciej
Published: March 2003

Immunoblotting of a repertoire of sperm antigens reacting with antisperm antibodies present in sera of infertile adults and prepubertal boys with testicular failure was performed. In the subgroups selected for this study, 55% of examined infertile women, 65% of infertile men and 64% of prepubertal boys with gonadal failure gave positive results by Western blotting with extracted sperm antigens. Sperm antigens with molecular weights of 57, 58, 62, 63 and 66 kDa were the most immunodominant entities recognized by antisperm antibodies from prepubertal boys. No positive reactions were detected by Western blotting in a control population of fertile adults, whereas in a group of prepubertal healthy boys only one sample revealed reactivity against sperm antigens of 58 and 70 kDa.
Thyroidectomy modulates rat prostatic monosaccharides
Authors: Maran  , Senthilkumaran  , Udhayakumar  , Arunakaran  , Aruldhas
Published: March 2003

Earlier studies have shown that thyroid hormones play an important role in glycoprotein metabolism in the prostate. In this paper, hypothyroidism induced changes in prostatic glycoprotein‐associated monosaccharides and fructose concentrations were studied in 30‐day‐old peripubertal rats. Hypothyroidism was induced by total surgical thyroidectomy and confirmed by radioimmunoassay (RIA) of thyroid hormones and thyroid stimulating hormone (TSH). Animals were killed after 30 and 60 days post‐thyroidectomy. To test the direct effect of thyroid hormones on prostatic monosaccharides, prostatic tissue was incubated for 24 h at 37 °C with 25, 50 or 100 ng/mL T3. Ventral prostatic hexosamines and sialic acid concentrations were significantly decreased in hypothyroid rats aged 30 and 60 days, whereas fucose concentration was increased at 30 days but decreased at 60 days in hypothyroid rats. In the case of the dorsolateral prostate, hypothyroidism enhanced the concentration of hexosamines but caused a decrease in levels of fucose, sialic acid and fructose, irrespective of the duration of hypothyroidism. Concentrations of fucose, fructose and hexosamines in the anterior prostate were decreased and sialic acid concentration was increased in 60‐day hypothyroid rats. In in vitro studies, the concentrations of fucose, sialic acid and hexosamines were significantly increased in all three prostatic lobes irrespective of the T3 dose with which they had been incubated. A consistent increase in fructose concentration was observed in anterior and dorsolateral prostates when incubated with different doses of T3 stimulation. It is concluded that the influence of hypothyroidism on prostatic monosaccharides seems to be specific for each sugar in different lobes of the prostate. These results clearly show that thyroid hormones differentially regulate prostatic glycoprotein metabolism.
Involvement of the calcium‐specific protease, calpain, in the fertilizing capacity of human spermatozoa
Authors: Rojas Francisco J. , Moretti‐Rojas Ines
Published: March 2003

We recently reported the novel finding that human spermatozoa contain the calcium (Ca2+)‐dependent protease, calpain. In somatic cells this protease mediates several cellular activities regulated by Ca2+ including membrane fusibility during cell‐to‐cell interactions. In this paper we examined the participation of sperm calpain in sperm–oocyte penetration, a process that is dependent on Ca2+ and involves membrane fusion between the two cells. Oocyte penetration was assessed using ejaculated spermatozoa from fertile men and zona‐free hamster oocytes. Penetration rate was impaired by the presence of the active‐site calpain inhibitor, calpain inhibitor‐I, in a dose‐dependent manner. At 1 mM, penetration scores were reduced by 65% (p < 0.01; n=5). The effects did not involve the oocyte, nor did the inhibitor alter sperm motility. Similar inhibitory effects on sperm penetration capacity were observed with specific antibodies directed either against calpain‐I or calpain‐II, the two forms of calpains described in somatic cells. At 1 : 1000 antibody dilution, penetration was inhibited 50 and 60% with anti‐calpain‐I and anti‐calpain‐II antibodies, respectively (p < 0.01; n=6). Furthermore, a combination of these two antibodies reduced the penetration rates by 75% (p < 0.01; n=6). We conclude that calpain inhibitor and anti‐calpain antibodies impair human sperm capacity to fuse and penetrate the oocyte. These findings suggest that sperm calpain is a novel component of the biochemical processes that regulate the fertilizing capacity of human spermatozoa.
Predictive factors of successful testicular sperm recovery in non‐obstructive azoospermia patients
Authors: Seo Ju Tae , Ko Woo‐Jin
Published: March 2003

Recovery of testicular spermatozoa from non‐obstructive azoospermic patients for intracytoplasmic sperm injection (ICSI) is a recent advance in the treatment of male infertility. The purpose of this study is to identify predictive factors for sperm recovery in non‐obstructive azoospermic patients. A total of 178 men with non‐obstructive azoospermia had multiple testicular sperm extraction (TESE) procedures to recover spermatozoa for intracytoplasmic sperm injection (ICSI) from June 1996 to February 1999. Testicular volume, serum follicle stimulating hormone (FSH) level and testicular histology were examined as positive predictive factors for sperm recovery. Testis biopsies were categorized as severe hypospermatogenesis, maturation arrest and Sertoli cell‐only syndrome based on the most advanced pattern of spermatogenesis seen on histology. Sperm retrieval success rates for the patients in three histopathological categories were compared. Spermatozoa were successfully recovered in 94 of 178 (52.8%) men. Sperm were retrieved in 13 of 80 (16.3%) with Sertoli cell‐only syndrome, 15 of 24 (62.5%) with maturation arrest, and 66 out of 74 (89.2%) with severe hypospermatogenesis. Spermatozoa recovery has no correlation with testicular volume or serum FSH level. When compared against Sertoli cell‐only syndrome, the odds of sperm retrieval success rate was 44.3 times higher in severe hypospermatogenesis and 8.4 times in maturation arrest. These results demonstrate meaningful correlation between successful testicular sperm recovery and testis histopathology. Only testicular histopathology can be used as a predictor of successful sperm recovery.
Comparative histopathology in mouse typhoid among genetically diverse mice
Authors: MONCURE CHARLES W. , GUO YAN‐NI , XU HONG‐RU , HSU
Published: March 2003

Genetically resistant CBA and A/J mice and susceptible BALB/c and C57BL/6 mice were challenged with either an identical infective dose or a minimal lethal dose of Salmonella typhimurium. The histopathological progression of the disease was examined in tissue sections prepared by the JB‐4 Plus resin embedding method and compared between the resistant and susceptible mice. In a fatal disease, the lesions in both animal hosts began with focal abscesses within the first three days post infection. Mononuclear cell infiltration started by day 4 and transformed the lesions into granulomata. Well‐formed granulomata were evident by day 7 and persisted in sublethally infected resistant mice. Massive bacterial proliferation and extensive tissue degeneration marked the terminal stage of a lethal challenge. There were no distinguishable features that would identify the tissue response to infection in a resistant host from a susceptible one, except that the lesions in the sublethally infected resistant mice advanced slower and were discrete and self‐limiting.
The current status of primary hepatocyte culture
Authors: Mitaka Toshihiro
Published: March 2003

Recently, there have been significant advances toward the development of culture conditions that promote proliferation of primary rodent hepatocytes. There are two major methods for the multiplication of hepatocytes in vitro: one is the use of nicotinamide, the other is the use of a nutrient‐rich medium. In the medium containing a high concentration of nicotinamide and a growth factor, primary hepatocytes can proliferate well. In this culture condition small mononucleate cells, which are named small hepatocytes, appear and form colonies. Small hepatocytes have a high potential to proliferate while maintaining hepatic characteristics, and can differentiate into mature ones. On the other hand, combining the nutrient‐rich medium with 2% DMSO, the proliferated hepatocytes can recover the hepatic differentiated functions and maintain them for a long time. In this review I describe the culture conditions for the proliferation and differentiation of primary hepatocytes and discuss the small hepatocytes, especially their roles in liver growth.
The vascular endothelial growth factor family; proteins which guide the development of the vasculature
Authors: ACHEN MARC G. , STACKER STEVEN A.
Published: March 2003

The development of the vascular tree during embryogenesis involves vasculogenesis, angiogenesis and tissue‐specific differentiation of endothelium which gives rise to many different vessel types. These processes are physiologically complex and are therefore difficult to study in vitro. However, the discovery of endothelial cell‐specific receptors and cognate ligands has led to the generation of transgenic and knockout mouse models which have shed light on the molecular mechanisms that regulate the development of blood and lymphatic vessels during embryogenesis. Such mouse models have demonstrated that members of the vascular endothelial growth factor (VEGF) family of proteins and the VEGF receptors are critical regulators of vasculogenesis, angiogenesis and endothelial cell differentiation. The availability of purified VEGF family members and of inhibitors of these growth factors may provide a means to modulate blood vessel growth for the treatment of cancer, retinopathies and diseases of ischemia.
Progression of renal disease in interleukin‐4 transgenic mice: involvement of transforming growth factor‐β
Authors: Rüger Beate M. , Hasan Qurratulain , Erb Klaus J. , Davis Paul F.
Published: March 2003

Recent reports have suggested the involvement of interleukin‐4 (IL‐4) in glomerular pathophysiology. Using immunohistochemistry and reverse transcriptase polymerase chain reaction we investigated the renal lesions in transgenic (tg) mice with widely distributed IL‐4 expression including the kidney, and measured the serum levels of the cytokines transforming growth factor‐β (TGF‐β) and IL‐4 by ELISA.

Transgenic animals exhibited glomerular hypertrophy with progressive mesangial sclerosis leading to renal failure. Renal IL‐4 transcript expression, mesangial accumulation of collagen types I, III, IV and V, and immune deposition accompanied by increased expression of TGF‐β1 protein and mRNA were observed. Seven day‐old transgenic animals showed early renal fibrotic changes in the absence of immune deposits or TGF‐β1 upregulation. The sera of transgenic mice not only showed elevated levels of circulating IL‐4 (tg: 76.6 pg/ml ± 7.1 vs wildtype (wt): < 3 pg/ml), but significantly decreased TGF‐β1 levels (tg: 18.9 ng/ml ± 4.1 vs wt: 38.7 ng/ml ± 2.9; P < 0.005). The disease severity correlated with the serum IL‐4/TGF‐β1 ratio rather than with the IL‐4 concentration.

These data suggest that renal IL‐4 production results in matrix accumulation prior to any immunological insult, that increased circulating IL‐4/TGF‐β1 ratios are associated with renal immunopathological manifestations and that upregulation of renal TGF‐β1 expression following glomerular Ig deposition accelerates the sclerosis and exacerbates disease development.
Analysis of dental emergencies presenting to a community paediatric dentistry centre
Authors: Lygidakis  , Marinou  , Katsaris
Published: March 2003

Objectives. The aim of this study was to investigate characteristics of child patients treated as emergencies in a community paediatric dentistry centre in Athens during the year 1992.Design, and method. Cross sectional analysis of records. From the emergency clinic records, the patient’s day of presentation, area of residence, age, sex, diagnosis made and treatment provided were recorded. The sample of children was divided into six groups according to their presenting complaint for purposes of analysis.Sample. 1271 children aged 8 months to 12 years, 680 boys and 591 girls presented as emergencies during the year 1992. 87 (7%) of the children were 0–3 years old, 276 (22%) 4–6 years, 610 (48%) 7–9 years and 298 (23%) were aged 10 years or over.Results. At their attendance as an emergency, 533 children (42%) presented with gingival swelling or sinus, 446 (35%) with toothache due to pulpitis, 142 (11%) following trauma, 86 (7%) with diffuse cellulitis and extra oral swelling, 52 (4%) for recementation of stainless steel crowns and space maintainers, and 12 (1%) for acute oral pathology problems. Amongst those presenting with symptoms arising as a result of dental caries, 607 children (57%) were treated endodontically with pulpotomy or pulpectomy (antibiotics were prescribed in 128 (27%) of these), and the remaining 458 (43%) by extraction of the teeth responsible. The 142 cases who presented following trauma had injuries to 20 primary and 221 permanent teeth. The most prevalent type of injury was crown fracture without pulp exposure (112 cases, 51%) followed by crown fractures with pulp exposure (73 cases, 33%), lateral luxation (9 cases, 4%), extrusive luxation (8 cases, 4%), crown and root fractures (6 cases, 3%), concussion and subluxation (6 cases, 3%), intrusion (4 cases, 2%) and avulsion (3 cases, 1%).Conclusions. The results of this study clearly show that although the prevalence of caries in Greece is declining, the disease still accounts for the majority of dental emergencies in child patients at this specialist centre. Provision of emergency dental care appears to be a vital part of NHS Community Services in our country, while a 24‐hour service, including weekends, could prove to be of greater value.
Oral myiasis: a case report
Authors: Bhatt A.P. , Jayakrishnan A.
Published: March 2003

Oral myiasis is a rare condition caused by the invasion of tissues by larvae of flies. A case of gingival myiasis is presented in a 12‐year‐old boy with learning disability. The patient was unaware of the lesion, although it produced a swelling partially covering the teeth. The lesion was treated with ether, which forced the larvae out, and irrigated with warm saline solution. Follow‐up examination revealed complete subsidence and healing of the lesion.
Dental care in acute lymphoblastic leukaemia: experiences of children and attitudes of parents
Authors: Collard M. M. , Hunter M. L.
Published: March 2003

Objectives. To profile the dental experiences of a group of children diagnosed as suffering from Acute Lymphoblastic Leukaemia (ALL) and to examine: 1) how parents of children diagnosed as suffering from ALL perceive the importance of dental care; 2) parental preferences with regard to the provision of dental care for children with ALL.

Setting. The study was conducted in one of the 22 United Kingdom Children’s Cancer Study Group (UKCCSG) centres.

Sample and methods. Data were collected by means of a structured interview, employing an administered questionnaire.

Results. The majority of children had attended a dentist both prior to, and following diagnosis, though the regularity of such attendance was variable and the receipt of dental preventive advice inconsistent. Parents appeared to place a high level of importance on their children’s dental care, with more than two‐thirds expressing a preference for this to be provided within the Paediatric Oncology Unit.

Conclusions. There is a need to establish means by which regular dental attendance may be encouraged and facilitated in the difficult circumstances posed following diagnosis. All healthcare professionals need to be equipped to give clear, consistent oral health advice. This, together with appropriate preventive measures, should be incorporated in oral care protocols. In accordance with the wishes of parents in this study, it is recommended that a comprehensive paediatric dental service be provided at all UKCCSG centres.
Developmental absence of the premolar teeth: dental management
Authors: Stephen L. X. G. , Basel D. , Beighton P. H.
Published: March 2003

Summary. A boy aged 11 years presented with dental pain, several carious teeth and a localized area of acute necrotizing ulcerative gingivitis (ANUG). Developmental absence of the premolar teeth was notable and additional anomalies included mid‐facial hypoplasia, mandibular prognathism, transposed teeth and delayed exfoliation of the deciduous teeth. These abnormalities have significant oral, dental, orthodontic and orthognathic implications.
Parental anxiety as a possible predisposing factor to child dental anxiety in patients seen in a suburban dental hospital in Nigeria
Authors: Folayan M. O. , Adekoya‐Sofowora C. A. , D. Otuyemi O. , Ufomata D.
Published: March 2003

Summary. Introduction. The aim of this study was to determine the relationship between parents’ anxiety level and that of the child patient.

Methods. The Short Form of the Dental Anxiety Survey Schedule was administered to 81 children who were attending the dental clinic for the first time. The Dental Anxiety Scale was also used to collect relevant information from the parents.

Results. There was no statistically significant correlation between the anxiety level of the mother (r = −0·02, P = 0·82) or the father (r = −0·59, P = 0·62) and that of their child. However, bivariate analysis showed a closer association between the anxiety levels of the mother and the child (P = 0·055) compared to that between the father and the child (P = 0·475) although this was again found not to be statistically significant.

Conclusion. Assessment and management of the anxiety level of the mother may be needed in some cases, both to manage the child effectively and to break the cycle of dental care anxiety in families.
Self‐report treatment techniques used by dentists to treat dentally anxious children: a preliminary investigation
Authors: Buchanan H. , Niven N.
Published: March 2003

Summary. Objective. To investigate the extent to which dentists report their encouragement to dentally anxious children to blunt (distract from the procedure) or monitor (give information about the procedure) during treatment.

Setting. British Society of Paediatric Dentistry conference.

Subjects and methods. One hundred and two of 155 delegates (66% response rate) completed a Monitor Blunter Treatment Checklist (MBTC), which was included in their conference pack. Participants were asked to tick all of the 10 statements (five monitoring and five blunting) that reflected how, in general, they would treat a dentally anxious child.

Results. Dentists chose significantly more monitoring than blunting statements. Treatment strategies relating to explaining procedures were endorsed by the majority of dentists, while distraction was chosen by less than a third.

Conclusion. Dentists tend to use monitoring strategies that adhere generally to the principles of the Tell‐Show‐Do technique. This may have implications if the anxious child has a ‘blunting’ coping style.
Nurses’ knowledge and opinions about the nursing research process in The Netherlands
Authors: Kyei M B
Published: March 2003

Nursing research is just gaining ground in The Netherlands, as it is in every European country Therefore, this study had the purpose of discovering to what extent Dutch nurses in the clinical areas have acquired research‐based knowledge since it was introduced into the country, in the 1970s Questionnaires, which included provision for demographic data, were distributed to 110 nurses, comprising head nurses, recently qualified nurses and final‐year student nurses A 65% response was achieved and the findings revealed that nursing research as a concept was not new to the Dutch nurses They claimed they had obtained their knowledge through nursing training, reading, conferences and other sources such as mass media The head nurses were the most knowledgeable followed by the recently qualified nurses and then the student nurses However, the respondents claimed that their knowledge was superficial The need to extend nurses’ knowledge through support and encouragement in relation to nursing research seminars and conferences is recommended