bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of adhesion of AML14.3D10 cells by surface clustering of β2‐integrin caused by ERK‐independent activation of cPLA2
Authors: Myou Shigeharu , Zhu Xiangdong , Boetticher Evan , Qin Yimin , Myo Saori , Meliton Angelo , Lambertino Anissa , Munoz Nilda M. , Hamann Kimm J. , Leff Alan R.
Published: March 2003

We examined the role of cell surface clustering of β2‐integrin caused by protein kinase C (PKC)‐activated‐cPLA2 in adhesion of eosinophilic AML14.3D10 (AML) cells. Phorbol 12‐myristate 13‐acetate (PMA) caused time‐ and concentration‐dependent adhesion of AML cells to plated bovine serum albumin (BSA), which was blocked by anti‐CD11b or anti‐CD18 monoclonal antibodies (mAb) directed against β2‐integrin. Inhibition of PKC with Ro‐31‐8220 or rottlerin blocked PMA‐induced cell adhesion in a concentration‐dependent fashion. Inhibition of cytosolic phospholipase A2 (cPLA2) with trifluoromethyl ketone or methyl arachidonyl fluorophosphonate also blocked PMA‐induced cell adhesion. PMA caused time‐dependent p42/44 mitogen‐activated protein kinase (MAPK) (ERK) phosphorylation in these cells. U0126, a MAPK/extracellular signal‐regulated protein kinase kinase (MEK) inhibitor, at the concentrations that blocked PMA‐induced ERK phosphorylation, had no effect on PMA stimulated AML cell adhesion. Neither p38 MAPK nor c‐Jun N‐terminal kinase (JNK) was phosphorylated by PMA. PMA also caused increased cPLA2 activity, which was inhibited by Ro‐31‐8220, but not U0126. Confocal immunofluorescence microscopy showed that PMA caused clustering of CD11b on the cell surface, which was blocked by either PKC or cPLA2 inhibition. PMA stimulation also caused up‐regulation of CD11b on the AML cell surface. However, this up‐regulation was not affected by cPLA2‐ or PKC‐inhibition. Using the mAb, CBRM1/5, we also demonstrated that PMA does not induce the active conformation of CD11b/CD18. Our data indicate that PMA causes AML cell adhesion through β2‐integrin by PKC activation of cPLA2. This pathway is independent of MEK/ERK and does not require change of CD11b/CD18 to its active conformation. We find that avidity caused by integrin surface clustering – rather than conformational change or up‐regulation of CD11b/CD18 – causes PMA stimulated adhesion of AML cells.
Histopathological outcome of Leishmania major‐infected BALB/c mice is improved by oral treatment with N‐acetyl‐l‐cysteine
Authors: Rocha‐Vieira Etel , Ferreira Ellen , Vianna Priscila , De Faria Daniela R. , Gaze Soraya T. , Dutra Walderez O. , Gollob Kenneth J.
Published: March 2003

Leishmania major infected BALB/c mice were treated with N‐acetyl‐l‐cysteine (NAC), a glutathione precursor, to evaluate the role of in vivo glutathione on lesion pathology and cytokine profiles following infection. Mice were maintained on NAC‐containing water 2 days before infection for a total of 14 weeks. The BALB/c response to L. major infection was improved by oral administration of NAC, at the level of histopathological outcome, lesion progression and cytokine profile. A significantly improved histopathological outcome of the footpad lesion, characterized by a mixed inflammatory infiltrate organized in a focal pattern with little tissue destruction and a reduced parasite load, was observed in NAC‐treated BALB/c mice. Histopathological modulation was accompanied by a modified cytokine pattern from popliteal lymph node cells, demonstrated by a sustained higher frequency of interferon‐γ (IFN‐γ) and tumour necrosis factor‐α (TNF‐α)‐producing cells. This work points to an important role for glutathione in the modulation of effector responses in BALB/c mice.
Constructing user requirements: a social process for a social context
Authors: Flynn Donal J. , Jazi Mohammad Davarpanah
Published: March 2003

We discuss our approach to constructing user requirements whereby users build requirements models themselves. The approach, termed user‐led requirements construction (ULRC), is a social process that addresses a major problem: the user‐developer culture gap. An important feature of the approach is that we have conducted, with users, an interpretivist empirical evaluation study of its constituent event flow diagram (EFD) modelling method and associated training. The ULRC has also been used in a live environment. The results are that users regard the EFD as effective for the requirements process, the EFD may be used for further studies to deepen our knowledge of the requirements process and the results contribute towards a set of public results for general evaluation and improvement.
Towards a framework for business process re‐engineering in small and medium‐sized enterprises
Authors: Chang Lih‐Jen , Powell Philip
Published: March 2003

Business process re‐engineering (BPR) is the vogue, although somewhat discredited, change management method. It is as an information technology (IT)‐based and customer‐driven approach to organizational change, undertaken to enable superior performance, such as cost reduction, shorter cycle time, higher product quality and increased customer satisfaction. Although the literature on re‐engineering principles and prospects is large, there is little empirical research evaluating the success or failure of BPR initiatives. This is especially so in small‐ and medium‐sized enterprises (SMEs) in which the potential for BPR benefits may differ significantly from that in their larger counterparts. SMEs are the fastest growing segment of most economies and are perceived to be more flexible and adaptable in terms of structure and speed of response than larger organizations. The literature speculates that SMEs have as good a chance of re‐engineering successfully as their larger counterparts, although this is untested. Yet, with limited resources, such as IT and BPR expertise, and financial constraints, SMEs may find it difficult to re‐engineer. This paper addresses the role of BPR in SMEs and develops a framework to assess its implementation potential. Factors that facilitate and inhibit BPR performance are identified and analysed as the basis for empirical testing. A set of propositions is developed that allows operationalization of the framework. The ultimate goal is to develop a process and tool set to assist SMEs wishing to undertake business process re‐engineering.
Design, development and implementation of a global information warehouse: a case study at IBM
Authors: Loeb Kathy A. , Rai Arun , Ramaprasad Arkalgud , Sharma Srinarayan
Published: March 2003

The characteristics of a global information warehouse (GIW) can be understood with reference to the three dimensions implied by the three words in its name. These dimensions are boundary of the system, semiotic level of the objects in the system, and organization of objects in the system, corresponding to the terms ‘global’, ‘information’ and ‘warehouse’, respectively. This paper defines these three dimensions and describes the system characteristics that flow from the definitions. These characteristics also highlight the issues involved in the design, development and implementation of GIWs. The case study following the discussion of the three dimensions illustrates these issues.
Commentary on ‘the effect of graphic style on data model interpretation’
Authors: Venable John R.
Published: March 2003

Abstract. In this issue, the paper by Nordbotten & Crosby, entitled ‘The effect of graphic style on data model interpretation’, attempts to establish a causal link between the graphic style of a conceptual data model (or data modelling language) and the success of users attempting to interpret instances of the use of that data model. It employs the novel technique of eye‐movement tracking to determine what is viewed or seen by the interpreters (experimental subjects) as an intermediary construct in the interpretation, in that what is not seen cannot be interpreted. It then further attempts to measure the success of the experimental interpretations and supposes that differences between subjects’ interpretations are caused by the differences in the graphic style of the various experimentally presented data models.
Information management in process‐based organizations: a case study at Xerox Ltd
Authors: Seltsikas Philip
Published: March 2003

Abstract. The process‐oriented holistic enterprise is a new organizational form in which the business process may be perceived as the basic organizational construct. Process management on an enterprise‐wide scale implies a complex integration of business processes. The increased organizational complexity places heavy demands on a firm’s information management capability, and this needs to be managed in a way that best supports the process model. This research has found that in the case of Xerox Ltd, a company that has adopted a holistic approach to process management, the information management process is key to supporting this method of organizing. The main finding is that, in order to support process management, a particular type of information management is required. This includes a need for enterprise‐wide information systems and the centralization of systems development and maintenance. However, the process management is made possible by this type of information management. This may be referred to as the duality concept of information and process management. The research presents findings from an in‐depth participant observation study conducted at the Xerox Ltd headquarters in the UK, and also includes data collected from Xerox France and Xerox UK.
Virtual positions: an examination of structure and performance in ad hoc workgroups
Authors: Vickery Caisson M. , Clark Thomas D. , Carlson John R.
Published: March 2003

Abstract. This paper examines the strength and performance of virtual positions within an organizational setting. Access to US Air Force systems acquisition teams provided a unique opportunity to study the phenomenon for a large number of virtual positions in a stable setting, thereby controlling for the differing aspects of organizational structure that usually make such positions difficult to study. A measurement scheme for the strength of the virtual position is developed and validated. A hierarchical regression analysis of research constructs dealing with power, autonomy, allegiance, structure and performance confirms that stronger virtual positions perform better in complex rather than simple task situations. Finally, managerial implications are discussed.
Eliciting information about organizational culture via laddering
Authors: Rugg Gordon , Eva Malcolm , Mahmood Atiya , Rehman Nazia , Andrews Stephanie , Davies Sarah
Published: March 2003

Abstract. Eliciting information about organizational culture is an important part of system analysis and design. However, eliciting knowledge of this sort is difficult. Laddering is an established technique that is particularly suitable for eliciting information about goals and for eliciting explanations, which are important issues when investigating organizational culture. This paper describes the method, its strengths and limitations, its use in several case studies and its relation to other elicitation techniques. Recommendations for further work are given.
Preparation and purification of DNA from insects for AFLP analysis
Authors: Reineke A. , Karlovsky P. , Zebitz C. P. W.
Published: March 2003

Analysis of amplified fragment length polymorphism (AFLP) has the potential to become a powerful new DNA fingerprinting technique for studying genetic relationships and genetic diversity in arthropods. Since DNA of high quality is a crucial prerequisite for AFLP analysis we evaluated the applicability of six protocols (one fast and four complex methods with phenol‐chloroform treatments as well as one CTAB‐based method) for extracting DNA from insect material and three additional DNA purification steps. The most rapid DNA isolation method did not produce DNA suitable for AFLP analysis. Among four complex methods tested, two protocols resulted in comparatively low yields of DNA that was therefore not used as template for AFLP analysis. The other two complex methods with phenol treatments and a CTAB‐based DNA extraction protocol provided DNA suitable for AFLP assay. An additional purification of the DNA using spermine precipitation revealed a few extra bands in an AFLP gel that were masked in unpurified DNA. Therefore spermine precipitation is recommended for AFLP templates.
Induction of cytochrome P450 CYP6B7 and cytochrome b5 mRNAs from Helicoverpa armigera (Hubner) by pyrethroid insecticides in organ culture
Authors: Ranasinghe C. , Hobbs A. A.
Published: March 2003

An organ culture system derived from Helicoverpa armigera has been used to study the expression of cytochrome P450 and cytochrome b5 mRNAs. Northern analysis showed that levels of the mRNAs for cytochrome P450s, CYP6B2, CYP6B6 and CYP6B7, and cytochrome b5 in control tissue were commensurate with those in the tissue of whole larvae. Substantial induction of cytochrome P450, CYP6B7 and cytochrome b5 mRNAs by α‐pinene, and the pyrethroids, fenvalerate, cypermethrin and permethrin were observed in fat body culture. Neither mRNA was induced, either in midgut or integument organ cultures. In contrast, the relatively water‐soluble compound phenobarbital, could induce CYP6B7 mRNA but not cytochrome b5 mRNA in fat body cultures. As for pyrethroids, phenobarbital had no effect on the other tissues in culture. These results confirm a previous conclusion that pyrethroids could induce CYP6B7 mRNA, which was based upon a very slight induction observed in living insects. Because many cytochrome P450 substrates can act as their inducers, these results support a previous conclusion that CYP6B7 could be the enzyme that is involved in pyrethroid resistance in H. armigera.
Microsatellite polymorphism in the Mediterranean fruit fly, Ceratitis capitata
Authors: Bonizzoni M. , Malacrida A. R. , Guglielmino C. R. , Gomulski L. M. , Gasperi G. , Zheng L.
Published: March 2003

A total of forty‐three simple sequence repeats (SSRs) were identified in the Mediterranean fruit fly (medfly) Ceratitis capitata. The most common SSR was the dinucleotide (TG)n/(CA)n occurring in thirty of the forty‐three microsatellite loci. Polymorphism at ten dinucleotide markers was investigated in 122 flies from six natural populations sampled in the native and colonized areas. A very high level of allelic diversity was detected in the species range. An average of 13.6 alleles was found over all the ten loci indicating the informativeness of SSRs as genetic markers for the medfly. The distribution of microsatellite polymorphism in the species range reflects the medfly colonization history.
Characterization of genes expressed in the salivary glands of the tsetse fly, Glossina morsitans morsitans
Authors: Li S. , Kwon J. , Aksoy S.
Published: March 2003

Salivary gland products of haematophogous insects including tsetse flies (Diptera: Glossinidia) are involved in antihaemostasis to allow for efficient blood feeding. In addition, salivary products of tsetse are thought to indirectly support the metacyclogenesis and eventual transmission of the African trypanosome protozoan parasites to their mammalian hosts. We have previously characterized the major anticoagulant, Tsetse Thrombin Inhibitor (TTI), from salivary extracts, and described molecular aspects of its cDNA from a Glossina morsitans morsitans salivary gland cDNA library. In addition, a family of two related genes with growth factor and adenosine‐deaminase motifs (TSGF‐1 and TSGF‐2) have also been described. Here, we report on the molecular aspects of three different cDNAs and their putative products expressed in salivary glands: cDNAs TAg5, Tsal1 and Tsal2. The full‐length transcript encoded by Tsetse Antigen 5 (TAg5) cDNA is 926 bp excluding the poly(A) stretch, and has an open reading frame of 259 amino acids that can encode for a protein of 28 925 Da. The putative product of TAg5 shows extensive similarities to cDNAs characterized from Drosophila (Agr and Agr2) and sandfly Lutzomyia (LuLoAG5). The cDNAs Tsal1 and Tsal2 are predicted to encode for mature proteins of 45 612 Da (399 amino acids) and 43 930 Da (389 amino acids), respectively, and their putative products exhibit over 42% identity to one another. The N terminus of each putative protein contains a hydrophobic region with signal peptide characteristics indicating that they may be secretory in nature. Transcripts specific for TAg5 and Tsal2 genes can be detected in all developmental stages of tsetse while Tsal1 expression is limited to adult and larval stages. A reverse transcription polymerase chain reaction based amplification approach indicates that TAg5 transcipts can be detected from proventriculus and midgut tissues of the fly in addition to salivary glands, while Tsal1 and Tsal2 expression is restricted to salivary gland and proventriculus. The salivary glands of adult males are found to express higher levels of TAg5 and Tsal2 in comparison to females while no significant sex‐based difference is observed for Tsal1 expression. The expression of these cDNAs in different tsetse species (G. m. morsitans, Glossina austeni and Glossina fuscipes) shows wide variations.
Theperiodgene and genetic differentiation between three Brazilian populations ofLutzomyia longipalpis
Authors: Bauzer L. G. S. R. , Souza N. A. , Ward R. D. , Kyriacou C. P. , Peixoto A. A.
Published: March 2003

Lutzomyia longipalpis(Diptera: Psychodidae: Phlebotominae), the main vector of visceral leishmaniasis in the Americas, is a putative species complex. Molecular polymorphism was characterized in a 266 bp fragment ofL. longipalpishomologous toperiod, a ‘speciation gene’ fromDrosophila. Samples from the Brazilian localities of Jacobina (BA), Lapinha (MG) and Natal (RN) were analysed and the data indicate that the three populations are highly differentiated, with a very low level of gene flow between them. These results are in agreement with published pheromone and copulation song studies that suggest the existence of a sibling species complex in Brazil.
A histopathological study of the morphological changes at the apical seat and in the periapical region after irradiation with a pulsed Nd:YAG laser
Authors: Koba  , Kimura  , Matsumoto  , Takeuchi  , Ikarugi  , Shimizu
Published: March 2003

In this study, the effects of pulsed Nd:YAG laser irradiation on the apical seat and periapical region of instrumented root canals were investigated. One hundred and ninety‐two teeth, including incisors and molars (239 root canals), in 18 healthy adult beagle dogs were used. After extirpation of the pulp under anaesthesia, each root canal was shaped up to at least a size 40 K‐file, and then laser irradiated using the following parameters: 1 W, 15 pps for 2, 3, and 4 s; 2 W, 15 pps for 2 s. The effectiveness of debris removal and carbonization on the root canal walls immediately after laser irradiation were examined and inflammation of the periapical region at 1, 2, and 4 weeks after laser irradiation was examined using light microscopy. Effective debris removal was observed in most cases in the laser‐treated groups and was dependent on irradiated energy. Carbonization was observed in the irradiated root canals except at the parameter of 1 W for 2 s. Periapical inflammation was observed at 1 W for 2 s to the same extent as in the control group (P > 0.01). These results suggest that the pulsed Nd:YAG laser is useful for debris removal with no adverse effects immediately after extirpation of the pulp if appropriate parameters are selected.
Apical transportation revisited or ‘Where did the K‐File go?’
Authors: Peters O. , Barbakow F.
Published: March 2003

Case report This case report describes the outcome of a number of retreatments on a failed root filling in a maxillary first molar. The patient wanted all amalgams replaced by tooth‐coloured Cerec1 restorations, including one in a symptomless maxillary molar. This tooth had a pulpotomy or a poorly done root‐canal treatment 10 years earlier. The molar was root‐canal retreated before placing the Cerec1 restoration and the palatal canal was filled 5 mm short of the radiographic apex. About 1 year later the patient presented with pain. Suspecting that a second mesiobuccal canal (MB‐2) had not been located, a second non‐surgical retreatment was instituted. MB‐2 was not found and the palatal canal was retreated a third time, setting the working length 2 mm short of the radiographic apex. Because pain persisted palatally an apicectomy was performed and the tooth became symptomless. The resected palatal root apex was subsequently serially cross‐sectioned, photographed and the canals analysed. Obvious apical transportation occurred during the cleaning and shaping procedures. Analyses of the canals showed that despite the retreatments, 11% of the canal cross‐sectional area remained uncleaned although 7% of the root area was ‘shaped’. Radiographically, the obturated palatal canal appeared reasonably well centred. However, this was disproved by the cross‐sections, indicating that in this case, the clinician did not know where the K‐Files had ‘gone’. Apically, the obturated canal was certainly not within the natural canal. The pain located palatally was probably due to inadequate cleaning and shaping of the apical part of the root canal and its accessory canals.
Thermal sensitivity of endodontically treated teeth
Authors: Tidwell E. , Witherspoon D. E. , Gutmann J. L. , Vreeland D. L. , Sweet P. M.
Published: March 2003

Case reports The problem of thermal sensitivity following non‐surgical root‐canal treatment is explored and case reports are presented. Possible causes for post‐treatment discomfort from endodontic and restorative

aetiologies are discussed, as are the mechanisms to explain the patients’ painful experiences. Treatment of this problem may vary from the simple replacement of a defective restoration to a more extensive non‐surgical retreatment of the case, despite radiographic evidence of an acceptable root filling and normal periradicular tissues.
A case of unusual anatomy: a maxillary lateral incisor with three canals
Authors: Peix‐Sánchez M. , Mi·ana‐Laliga R.
Published: March 2003

Case report A case of an unusual maxillary lateral incisor with three root canals is presented. The patient

presented with localized swelling and a sinus tract. Because of its abnormal anatomical configuration, the tooth presented diagnostic and procedural difficulties. Conventional root canal treatment was performed successfully.
Apex formation during orthodontic treatment in an adult patient: report of a case
Authors: Fava L. R. G.
Published: March 2003

This clinical report describes an apexification procedure on a maxillary left central incisor in a 34‐year‐old male who was also receiving active orthodontictreatment. The pulp of the tooth had become necrotic following a traumatic injury when the patient was 8 years of age. Despite the tooth undergoing active orthodontic repositioning with fixed appliances, root‐end closure occurred uneventfully and within 3 years.
Newly developed resinous direct pulp capping agent containing calcium hydroxide (MTYA1‐Ca)
Authors: Niinuma A.
Published: March 2003

Niinuma A. Newly developed resinous direct pulp capping agent containing calcium hydroxide (MTYA1‐Ca). International Endodontic Journal, 32, 475–483 1999.

Aim The aim of this study was to evaluate a newly developed resin (MTYA1‐Ca) for direct pulp capping.

Methodology The powder of MTY1‐Ca is composed of 89.0% microfiller, 10.0% calcium hydroxide and 1.0% benzoyl peroxide and was mixed with liquid (67.5% triethyleneglycol dimethacrylate, 30.0% glyceryl methacrylate, 1.0% o‐methacryloyl tyrosine amide, 1.0% dimethylaminoethylmethacrylate, and 0.5% camphorquinone). The shear bond, diametral tensile, bending and compressive strengths were measured. The alkaline activity of the eluate dissolved from MTYAl‐Ca was calculated. Cell viability by MTT assay and alkaline phosphatase (ALPase) activity were evaluated from dental pulp fibroblast reaction to the eluate dissolved from MTYAl‐Ca. Histopathological studies of the response to exposed dental pulp of beagle dogs were completed with Dycal as a control.

Results The physical properties of MTYAl‐Ca were significantly superior to those of Dycal. It was impossible to measure these properties with Dycal because of poor physical properties. Both MTYA1‐Ca and Dycal maintained high levels of alkaline activity (pH 10.96–12.20) over the 168‐h duration of the study. Cell viability by MTT assay in the intact eluate of MTYAl‐Ca was significantly higher than that of Dycal, whilst ALPase showed no difference between MTYAl‐Ca and Dycal. A dentine bridge formed more slowly under MTYA1‐Ca than under Dycal, but similar amounts had formed at 90 days.

Conclusions MTYAl‐Ca has the potential to be used as a direct pulp capping material.
Determination of endotoxins in caries: association with pulpal pain
Authors: Khabbaz M. G. , Anastasiadis P. L. , Sykaras S. N.
Published: March 2003

Khabbaz MG, Anastasiadis PL, Sykaras SN. Determination of endotoxins in caries: association with pulpal pain. International Endodontic Journal, 33, 132–137 2000.

Aim  The aims of this study were: (i) to determine the presence or absence of endotoxins in the superficial and deep layers of carious lesions of symptomatic and asymptomatic teeth with vital pulps; (ii) to quantify the amount of endotoxin present; and (iii) to associate the presence of endotoxins with the acute pulpal pain derived from the irreversible pulpitis.

Methodology Two specimens of carious dentine were taken under aseptic conditions from symptomatic teeth with irreversible pulpitis (n = 9) and asymptomatic teeth with reversible pulpitis (n = 11). The first specimen was taken from a layer of superficial caries and the second from a deeper one. Sound dentine was also collected from intact teeth without restoration and used as a noncarious control group (n = 4). During the patient sampling procedure an effort was made to collect an equal quantity of caries and sound dentine in all cases (approximately 6 mg).

The extraction of endotoxins was performed using the Phenol–water method. The assay and quantitative determination of endotoxins was performed by the Quantitative Chromogenic test using Limulus Lysate. Data were analysed statistically using either independent or paired t‐tests.

Results  The results indicated that endotoxins were present in the superficial and deep layers of caries of all symptomatic teeth with irreversible pulpitis (0.15078 and 0.12111 ng mL−1, respectively), with significantly greater amount (P< 0.01) in the superficial compared to the deep layer. Endotoxins were found in superficial and deep layer of caries of all asymptomatic teeth with reversible pulpitis (0.12091 and 0.07163 ng mL−1, respectively), with significantly greater amounts (P< 0.001) in the superficial compared to the deep layer.

The results also demonstrated that significantly greater concentrations (P <0.005) of endotoxins were present in the superficial carious layer of symptomatic compared with asymptomatic teeth (0.15078 and 0.12091 ng mL−1, respectively). Likewise, significantly greater amounts (P <0.001) of endotoxins were present in the deep carious layer of symptomatic compared with asymptomatic teeth (0.12111 and 0.07163 ng mL−1, respectively). In sound dentine no endotoxins were detected.

Conclusions  This study demonstrates that endotoxins are present in carious lesions of symptomatic and asymptomatic teeth. The amount of endotoxin was significantly greater in the superficial compared to the deep layer of carious dentine. More endotoxins are present in caries of painful teeth compared with those without symptoms.
The standardized‐taper root canal preparation – Part 6. GT file technique in abruptly curved canals
Authors: Buchanan L. S.
Published: March 2003

Aim  To describe the application of GT files in roots with abrupt curvatures.

Summary Most dentists interpret obstructions to instrument progress as calcification, rather than abrupt curvature. Basically, there are not any apically calcified canals, only clinicians who are not clever enough or patient enough to sneak to patency. Dentists should be on their guard and sensitive to the ‘rubber band’ sensation of residual pulp tissue, and the ‘loose resistance’ sensation of the curved or ledged canal. Residual pulp tissue should be removed and the canal lubricated. The ledged or curved canal will only be helped by file bending. The size 10 file test is the key to identify canals requiring pre‐bent instruments.

The canal should first be flared short of the obstruction, before shaping the canal after it with regular, pre‐bent K‐files. Pre‐bent GT hand‐files can then be used with care to blend the apical and more coronal regions for final shape. Cone‐fit may then require chilling and pre‐bending GP cones (pre‐bend more than one), before packing the canal.

Key learning points

Root canals do not calcify apically.

File progress is prevented by pulp tissue, abrupt curvatures or ledging.

Loose resistance to the passage of a size 10 file shows the canals that require instrument pre‐bending. This test should be repeated at intervals during the preparation.

Even NiTi GT files can be pre‐bent for use in abrupt curves.

Gutta percha cones can be pre‐bent after chilling.
In vivo determination of root canal length: a preliminary report using the Tri Auto ZX apex‐locating handpiece
Authors: Grimberg F. , Banegas G. , Chiacchio L. , Zmener O.
Published: March 2003

Aim The aim of this study was to assess the clinical perfomance of a cordless handpiece with a built‐in apex locator – the Tri Auto ZX – designed for root canal preparation with nickel‐titanium rotary files.

Methodology Twenty‐five human maxillary incisor and canine teeth scheduled for extraction with mature apices were selected for the study. Informed written consent was obtained from each patient before treatment. After administration of local anaesthesia, the teeth were isolated and the pulp cavities accessed. The Tri Auto ZX along with a size 15 K‐file was used in its electronic apex locating function based on the manufacturer's recommendations. A periapical radiograph with the file at the electronically determined constriction was taken, the file removed and the measurement registered as the electronic length (EL). To test the auto reverse function, a size 20 ProFile .04 taper NiTi rotary instrument was mounted in the handpiece. The point for the auto apical reverse function was preset on the panel at the 0.5 mm level. After the file was introduced into the canal and reached the predetermined level, the file automatically stopped and rotated in the opposite direction. A reference point was marked and this measurement was registered as the auto reverse length (ARL). All measurements were made twice by two different investigators. Teeth were then extracted and immersed in a 20% formalin solution for 48 h. After fixation, a size 15 file was inserted into the canal to measure the actual root canal length from the same reference point obtained with the Tri Auto ZX to the apical foramen, as seen in the stereo microscope. When the file tip was visible at the anatomical end of the canal it was withdrawn 0.5 mm and this measurement was registered as the actual length (AL). All measurements were expressed in mm and the measuring accuracy was set to 0.5 mm. The significance of the mean differences between EL and ARL and between EL and AL measurements at the 5% confidence level was evaluated.

Results EL measurements were coincident to ARL in all instances. EL and ARL were coincident to AL in 10 (40%) canals, in the remaining 15 canals (60%) the AL measurements were longer than EL and ARL (+0.5 mm) in 14 instances and shorter (–0.5 mm) in one case. Overall, the AL was longer than the EL or ARL, the mean difference being –0.23 mm ± 0.32 (P < 0.05).

Conclusions It was concluded that the Tri Auto ZX was useful and reliable. The Tri Auto ZX measurements protected against overpreparation.
Topographical uptake of blood‐borne horseradish peroxidase (HRP) in the murine testis at the light microscopic level
Authors: ITOH MASAHIRO , UENO MASAKI , LI XIU‐QIN , SATRIOTOMO IRAWAN , TAKEUCHI YOSHIKI
Published: March 2003

Light microscopical studies on the uptake of blood‐borne horseradish peroxidase (HRP) in large areas of the testis have been scarce because of the difficulty of staining HRP in testes with well‐preserved morphology. However, observation of exogenous HRP in all areas of the testis enables detection of regional tissue injury induced by toxic chemicals or immunization. In the present study, the localization of blood‐borne HRP in the murine testis was investigated light microscopically using plastic‐embedded testes and post‐embedding histochemical methods. Mice were injected intravenously with HRP, and then perfused with 2.5% glutaraldehyde and 3% paraformaldehyde in 0.1 M phosphate buffer. The fixed testes were immediately removed, dehydrated, and then embedded in plastic without cutting them into small pieces. The prepared sections treated by the diaminobenzidine method exhibited intense HRP activity with well‐preserved testis morphology. It was noted that many interstitial macrophages had endocytosed HRP. In particular, HRP‐endocytosing macrophages were concentrated around the tubuli recti. The testicular capsule, containing many lymphatic capillaries and vessels, was also loaded with HRP. In the subcapsular interstitium, free HRP in the lymph space accumulated, but the staining intensity was weak compared to that in testicular macrophages. No HRP infiltration into the lumen of the seminiferous tubules was observed at the light microscope level; however, HRP staining was detected in tubular walls and epithelial cells lining the rete testis and tubuli recti, indicating that these regions are permeable to HRP.
The effects of feeding an Asian or Western diet on sperm numbers, sperm quality and serum hormone levels in cynomolgus monkeys (Macaca fascicularis) injected with testosterone enanthate (TE) plus depot medroxyprogesterone acetate (DMPA)
Authors: Suhana  , Sutyarso  , Moeloek  , Soeradi  , Sri Sukmaniah  , Supriatna
Published: March 2003

The aim of this study was to elucidate the effects of an Asian diet compared to a Western diet on sperm numbers and quality, and serum hormones in cynomolgus monkeys (Macaca fascicularis) injected with testosterone enanthate (TE) plus depot medroxyprogesterone acetate (DMPA). Thirty male monkeys were divided into three groups of ten animals each. The first group (control) was fed with standard diet ‘monkey chow’ (9% fat, 13% protein, 78% carbohydrate); the second group was fed an ‘asian’ diet (15% fat, 15% protein, 70% carbohydrate); the third group was fed a ‘Western’ diet (35% fat, 25% protein, 40% carbohydrate). These diets were administered from the beginning (adaptation) until the experiment was terminated. Three months after the adaptation period, all groups were injected with 20 mg TE (once per week) and 25 mg DMPA (once every 6 weeks) for 18 weeks, while TE injections were continued for another 6 weeks. There were no differences in sperm numbers and quality, or in hormone levels between the first and second groups. In both of these groups azoospermia was achieved in 100% of animals, while in the third group only 70% achieved azoospermia. In all 3 groups, spermatozoa were once again detectable by week 33. However, by the end of the study at week 39, sperm numbers in the first and second groups reached only severe oligozoospermia (two animals remained azoospermic in the first group) while in the third group, numbers had returned to normozoospermia. The quality of spermatozoa during and after the treatment in the third group was better than in the first and second groups. Hormone concentrations decreased more rapidly in both the first and second groups, compared to the third group, while the recovery period was slower in the first and second groups, compared to the third group. It is concluded that different formula diets result in differential decreases in sperm numbers and quality, and in hormone concentrations in M. fascicularis injected with TE in combination with DMPA. Animals fed with either monkey chow or an Asian diet exhibited more severe and prolonged decreases in these parameters than did animals fed with a Western diet.
In vitro inhibition of superoxide anion production and superoxide dismutase activity by zinc in human spermatozoa
Authors: Gavella  , Lipovac  , Vučić  , Šverko
Published: March 2003

The in vitro effect of zinc on superoxide anion (O2–) generation and on SOD‐like activity in spermatozoa of infertile men was investigated. The formation of superoxide anion was stimulated by NADPH and the level of superoxide anion was measured by the reduction of ferricytochrome c. Both Percoll‐isolated (n=14) and washed spermatozoa (n=14) exposed to 1 mmol/L zinc (60 min, 37 °C), released less (p < 0.002 and p < 0.04, respectively) superoxide anions than did zinc‐untreated spermatozoa. These results implicate a possible role for zinc as a scavenger of excessive superoxide anions produced by defective spermatozoa in semen after ejaculation. Additionally, zinc was found to dose‐dependently inhibit superoxide dismutase (SOD)‐like activity of spermatozoa in vitro. The inhibition of SOD‐like activity by an equal concentration of zinc (1 mmol/L) was less pronounced in oligospermic (p < 0.002; n=16) and asthenozoospermic (p < 0.0005; n=20) than in normozoospermic samples (p < 0.0001; n=20). This differential ability of zinc to inhibit SOD‐like activity may be relevant to the physiological function of spermatozoa in fertilization. The evidence that zinc may elicit an inhibition of both superoxide anion production and SOD‐like activity in human spermatozoa, indicate the existence of novel, zinc‐related mechanism(s) involved in the oxidative events occurring after ejaculation, with a possible modulatory effect on germ cell function.
Major differences between the testis and epididymis in the induction of granulomas in response to extravasated germ cells. I. A light microscopical study in mice
Authors: Itoh Masahiro , Xie Qiang , Miyamoto Kensaku , Takeuchi Yoshiki
Published: March 2003

A spermatic granuloma is a chronic inflammatory lesion which surrounds extravasated spermatozoa. Clinically, the lesion develops in the interstitial spaces of the epididymis and vas deferens, and only exceptionally in the testis itself. In the present study, murine testes and epididymides were injured using a needle and the histological appearances of these organs was then compared. Traumatic injury induced extravasation of germ cells in both testes and epididymides. A few days later, spermatic granulomas consistently formed in the epididymides, however, such lesions were not induced in the testes. To examine the possibility that epididymal spermatozoa have inherently greater ability to form spermatic granulomas than do testicular germ cells, isolated epididymal spermatozoa or testicular germ cells were locally injected into the testes and epididymides of recipient mice. Spermatic granulomas readily formed in the epididymides after local injection of either epididymal spermatozoa or testicular germ cells. In contrast, such lesions did not form in the testes even when epididymal spermatozoa were injected. Therefore, this study suggests that the microenvironment of the testicular interstitium, rather than the extravasated components from the ruptured seminiferous tubules, is the main factor determining the limited formation of spermatic granulomas in the testis.
Current status of reproductive function in Japanese fertile men: international collaborative project on a study of partners of pregnant women
Authors: Baba Katsuyuki , Nishida Takayasu , Yoshiike Miki , Nozawa Shiari , Hoshino Takao , Wamoto Teruaki
Published: March 2003

The data on reproductive function in 255 Japanese fertile men resident in the Kawasaki/Yokohama area in Japan were described. The sperm concentration was 107.9 ± 97.4 × 106/mL. The semen volume was 3.2 ± 1.5 mL and percentage motile spermatozoa (grade A + B in WHO criteria) was 56.8% ± 14.7%. The evidence for secular changes in semen quality and other changes in male reproductive health is inconclusive, although regional differences would appear to be stronger. The present study is the first large‐scaled prospective survey on the reproductive function of Japanese normal men proven fertility, which was planned as an international comparative study.
Oocyte activation induced by spermatids and the spermatozoa
Authors: Yanagida Kaoru , Yazawa Hiroyuki , Katayose Haruo , Kimura Yasuyuki , Hayashi Syotaro , Sato Akira
Published: March 2003

It has been reported that a sperm factor (SF) found in spermatozoa plays a critical role in fertilization. However, particulars of the oocyte‐activating and Ca2+ oscillation (Ca‐Os)‐inducing abilities of this SF remain unknown. We examined these abilities of spermatids in mouse, hamster and human by a mouse test (injection of spermatids into mouse oocytes). In mice, the round spermatids (ROS), elongated spermatids (ELS) and spermatozoa activated 0%, 93% and 92% of the oocytes, respectively. ROS injection resulted in no Ca‐Os (type C). ELS induced a normal oscillation (type A) at 0% and an abnormal oscillation (type B) at 94%. Mouse spermatozoa induced type A Ca‐Os at 90%. For mice, oocyte‐activating and Ca2+ oscillation‐inducing ability arose in different phases of spermiogenesis. We also observed this differential timing for hamster spermatids. Hamster ROS activated 74% of oocyte (ELS: 90%, sperm: 86%). Human ROS activated 64% of oocytes (sperm: 100%), but only 35% of the oocytes showed type A Ca‐Os. These results indicate that oocyte activation generally occurs between the ROS and ELS phases, although these phases differ among species. They also indicate that oocyte activation is not necessarily accompanied by Ca‐Os. These findings suggest the existence of different thresholds at which the SF induces oocyte activation and Ca2+ oscillation, or of different factors that induce oocyte activation and Ca‐Os. We found SF to be clinically impaired in 0.9% of ICSI patients. A combination of artificial oocyte activation and ICSI proved effective with such patients.
Repeated vas occlusion and non‐invasive reversal with styrene maleic anhydride for male contraception in langur monkeys
Authors: Lohiya N. K. , Manivannan B. , Mishra P. K.
Published: March 2003

The feasibility of a spacing method for contraception, using Styrene Maleic Anhydride (SMA) as a vas occlusive agent, has been assessed in male langur monkeys. The vas deferens of 6 animals were occluded with 60 mg SMA in 120 μL DMSO. After 150 days, the occlusion was reversed by a technique which involved palpation, percutaneous electrical stimulation, forced vibratory movement, suprapubic percussion and per‐rectal digital massage of the vas segments. The vas deferens were then re‐occluded with SMA and reversed by the non‐invasive method after three consecutive azoospermic samples. The second vas occlusion resulted in uniform azoospermia after the third ejaculation and reversal caused the reappearance of spermatozoa in the semen to severe oligozoospermic levels in the first two ejaculations and rising to normospermia in the subsequent ejaculations. Ultrastructure of the spermatozoa by SEM and TEM and sperm function tests revealed that the spermatozoa had recovered normal morphology. Vas morphology also regained a normal pseudostratified columnar epithelium containing basal and principal cells. The results suggest that the SMA‐based spacing technique for male contraception could be extrapolated to the human by use of no‐scalpel injection and non‐invasive reversal.
Birthweight and semen characteristics
Authors: Olsen JØrn , Bonde Jens Peter , Basso Olga , Hjøllund Niels Henrik I. , SØrensen Henrik Toft , Abell Annette
Published: March 2003

A correlation between birthweight and sperm counts in adult life was anticipated because impaired fetal growth could impair replication of Sertoli cells produced in fetal life. Furthermore, it was expected that males born with a high birthweight might have impaired sperm production as they are expected to have been exposed to higher levels of oestrogen in fetal life. We examined these predictions by including midwives records for 296 Danish males that had taken part in studies on male fecundity for other reasons. The study provided no support for these expectations. If anything, males born with a birthweight of 3000–3999 g had slightly lower sperm counts and more abnormal spermatozoa.
Reproductive function in male rats after brief in utero exposure to diethylstilboestrol
Authors: Behrens G. H. G. , Petersen P. M. , Grotmol T. , SØrensen D. R. , Torjesen P. , Tretli S. , Haugen T. B.
Published: March 2003

Long‐term effects of brief in utero exposure to diethylstilboestrol (DES) during a foetal period known to be critical for gonadal development were evaluated. Rats were exposed to DES (100 μg/kg body‐weight) from day 17 to 19 of pregnancy. All of the DES‐treated pregnant rats (11/11) ate parts or whole of their offspring during the first day after birth (p=0.03). Surviving male offspring were examined on day 63 post‐partum. DES induced a reduction in weight of the testis (p=0.06) and ventral prostate (p=0.07), even after this short exposure. DES tended to reduce the number of Sertoli cells (p=0.13). Our findings indicate that even a short in utero exposure of rats to DES during a critical period for gonadal development results in cannibalism and reduced testis and ventral prostate weight.
Irrigation of the distal vas deferens during vasectomy: does it accelerate the post‐vasectomy sperm‐free rate?
Authors: Leungwattanakij Somboon , Lertsuwannaroj Apirak , Ratana‐Olarn Krisada
Published: March 2003

A prospective, non‐randomized, partially blinded, controlled trial was conducted to evaluate the efficacy of irrigation with normal saline solution (NSS) during no‐scalpel vasectomy (NSV) compared with NSV alone in 62 men. In the NSS irrigation group, an Angiocath 24‐gauge needle was inserted into the distal vas lumen, and 20 mL NSS solution was used to irrigate the vas manually on both sides. Post‐operative follow‐up included urine samples collected immediately and semen samples for sperm count at 2, 6 and 12 weeks post‐vasectomy. The difference in the number of spermatozoa appearing in the post‐vasectomy urine samples and the mean urine sperm count in both groups were significantly different ( p < 0.0001 and p < 0.01, respectively). The numbers of post‐operative ejaculations, the mean sperm concentration, and the number of patients who achieved sterility (defined as no motile spermatozoa in the ejaculate) in both groups at 2, 6 and 12 weeks were similar ( p > 0.05). It is concluded that although irrigation of the distal vas with NSS was successful in removing a large number of spermatozoa from the tract, this procedure did not significantly accelerate the rate of achieving absence of motile spermatozoa in the ejaculate.