bluuebunny/crossref_metadata_2025 huggingface dataset:
Imaging of primary human hepatocytes performed with micron‐sized iron oxide particles and clinical magnetic resonance tomography
Authors: Raschzok Nathanael , Morgul Mehmet H. , Pinkernelle Jens , Vondran Florian W. R. , Billecke Nils , Kammer Nora N. , Pless Gesine , Adonopoulou Michaela K. , Leist Christian , Stelter Lars , Teichgraber Ulf , Schwartlander Ruth , Sauer Igor M.
Published: April 2008

Transplantation of primary human hepatocytes is a promising approach in certain liver diseases. For the visualization of the hepa‐tocytes during and following cell application and the ability of a timely response to potential complications, a non‐invasive modality for imaging the transplanted cells has to be established. The aim of this study was to label primary human hepatocytes with micron‐sized iron oxide particles (MPIOs), enabling the detection of cells by clinical magnetic resonance imaging (MRI). Primary human hepatocytes isolated from 13 different donors were used for the labelling experiments. Following the dose‐finding studies, hepatocytes were incubated with 30 particles/cell for 4 hrs in an adhesion culture. Particle incorporation was investigated via light, fluorescence and electron microscopy, and labelled cells were fixed and analysed in an agarose suspension by a 3.0 Tesla MR scanner. The hepatocytes were enzymatically resuspended and analysed during a 5‐day reculture period for viability, total protein, enzyme leakage (aspartate aminotransferase [AST], lactate dehydrogenase [LDH]) and metabolic activity (urea, albumin). A mean uptake of 18 particles/cell could be observed, and the primary human hepatocytes were clearly detectable by MR instrumentation. The particle load was not affected by resuspension and showed no alternations during the culture period. Compared to control groups, labelling and resuspension had no adverse effects on the viability, enzyme leakage and metabolic activity of the human hepatocytes. The feasibility of preparing MPIO‐labelled primary human hepatocytes detectable by clinical MR equipment was shown in vitro. MPIO‐labelled cells could serve for basic research and quality control in the clinical setting of human hepatocyte transplantation.
Frabin and other related Cdc42‐specific guanine nucleotide exchange factors couple the actin cytoskeleton with the plasma membrane
Authors: Nakanishi Hiroyuki , Takai Yoshimi
Published: April 2008

Introduction

Molecular structures of frabin and other related GEFs

Tissue distribution, subcellular localization and splicing variants of frabin and other related GEFs

Cellular activities of frabin and other related GEFs

Roles of the domains of frabin in cellular activities

Mode of action of frabin in cell shape changes

Mode of activation of frabin and FRG

Involvement of FGD4/frabin and FGD1 in human diseases

Conclusions and perspectives

Frabin, together with, at least, FGD1, FGD2, FGD3 and FGD1‐related Cdc42‐GEF (FRG), is a member of a family of Cdc42‐specific gua‐nine nucleotide exchange factors (GEFs). These proteins have multiple phosphoinositide‐binding domains, including two pleckstrin homology (PH) domains and an FYVE or FERM domain. It is likely that they couple the actin cytoskeleton with the plasma membrane. Frabin associates with a specific actin structure(s) and induces the direct activation of Cdc42 in the vicinity of this structure(s), resulting in actin reorganization. Furthermore, frabin associates with a specific membrane structure(s) and induces the indirect activation of Rac in the vicinity of this structure(s), resulting in the reorganization of the actin cytoskeleton. This reorganization of the actin cytoskeleton induces cell shape changes such as the formation of filopodia and lamellipodia.
An evaluation of the preclinical prosthodontic training at the Faculty of Dentistry, University of Bergen, Norway
Authors: Ingebrigtsen Jana , Røynstrand Edvard , Berge Morten E.
Published: April 2008

The curriculum of the dental faculty at the University of Bergen was revised and a new curriculum was implemented in 2000. The first candidates graduated in 2003. In the new curriculum the theoretical teaching consists of an extended integrated lecture series in prosthodontics and biomaterials. The revised laboratory course includes an increased number of tooth preparations performed on phantom heads solely. Newer types of preparations based on bonding technique, such as ceramic crowns, veneers and inlays, have also been introduced. As a consequence of the reduced time allocated to the course, the amount of dental technical work has been considerably reduced. Demonstrations of practical procedures are video‐based. Several theoretical and practical tests are carried out during the course. The purpose of this study was to assess the outcome of the alterations made, by comparing former students’ opinions on different aspects of the two curricula. A questionnaire was mailed to the students graduated in 2003 with the new curriculum and graduates in 1997 and 2000 with the ‘old’ curriculum. The results indicate that the alterations tended to improve the students’ evaluations of some aspects of the course. In addition, the new curriculum appeared to be more relevant for the succeeding work in the clinic.
What becomes of dental research trainees once they leave the Dental Research Institute? An analysis over 53 years
Authors: Grossman E. S. , Cleaton‐Jones P. E.
Published: April 2008

The careers of 131 dental research trainees were followed (1954–2007) to establish whether and how they utilised their research training in keeping with clinical research workforce needs. The Dental Research Institute database was used to obtain trainee demographic, teaching and research outputs which were examined according to degree types: PhD (18); MSc (55); MDent (42) and dropout (16). Current careers show that 48% are in exclusive private practice and 15% in exclusive academia with further 15% practitioners having academic links via sessional teaching or research at a dental school. Most (63%) have remained in South Africa but emigration is high amongst the PhD and MSc groups. Forty‐one per cent of the cohort is of age ≤55 years and 16% <40 years old. The 131 trainees have published 2287 peer‐reviewed journal papers over their careers: quantity of research output is skewed towards degree type (PhD) and individuals (10% trainees produced 65% of all publications). Recent trainees have little research experience prior to their training and a lower subsequent research output than earlier trainees. PhDs have participated in research for the greatest length of time (29.1 years). Academic teaching is heavily reliant on older and PhD trainees. It is proposed that a threshold of four publications be used to indicate minimum research skills and a period of formal academic teaching taken into account when advocating criteria to assess clinical research workforce requirements.
Understanding the motivation: a qualitative study of dental students’ choice of professional career
Authors: Gallagher J. , Clarke W. , Wilson N.
Published: April 2008

Background:  Given the changing nature of the dental workforce, and the need to retain the services of future members, it is important to understand why current dental students perceive that they were motivated to study dentistry. Qualitative research provides the opportunity to explore the underlying issues in addition to informing subsequent quantitative research. The objectives of this research were to investigate final‐year dental students’ motivation for studying dentistry and how they perceive this has been modified during their undergraduate degree programme.

Methods:  Purposive sampling of a representative group of 35 final‐year dental students at King’s College London Dental Institute to participate in audio‐taped focus groups. Qualitative data were analysed using Framework Methodology.

Results:  The findings suggest a strong emphasis on having a career, providing ‘professional status’, ‘financial benefits’, ‘job security, flexibility and independence’ and ‘good quality of life’. Students reported being attracted by features of the job, supported to a greater or lesser extent by personal experience, family and friends. It appears however that students’ initial motivation is being tempered by their experiences during their undergraduate degree programme, in particular, the ‘responsibilities of an intensive professional education’, their ‘mounting student debt’ and the perception of ‘feeling undervalued’. This perception related to dentistry in general and National Health Service dentistry in particular, being undervalued, by government, patients, the public and members of the dental profession.

Conclusions:  Students’ vision of a ‘contained professional career’ within health care, providing status and financial benefits, appears to have influenced their choice of dentistry. Pressures relating to student life and policy changes are perceived as impacting on key components of professional life, particularly status in the social and economic order. The implications for educators, professional leaders and policy makers are explored.
The evaluation of an approach to reflective learning in the undergraduate dental curriculum
Authors: Bush H. , Bissell V.
Published: April 2008

Students in higher education are being encouraged to become active, independent and life‐long learners. The use of progress files has been endorsed to encourage this approach. A portfolio intended to fulfil the role of a progress file and to promote student‐centred learning and reflection was introduced as a central component of the revised undergraduate degree at the Glasgow Dental School in 2004. This article evaluates its role in promoting reflection. Students following the Bachelor of Dental Surgery (BDS) programme completed three written reflections per year using structured proformas, and discussed them with their mentor and mentoring group. Their views of the portfolio and of reflection were gathered using a five‐point Likert scale. In BDS1 2004–5, 84% completed a questionnaire, as did 89% in BDS1 2005–6 and 99% in BDS2 2005–6. Most students did not enjoy reflecting (a finding commonly reported elsewhere) or feel that reflection identified their learning needs. It appears that students disliked writing reflections, rather than reflecting per se. In contrast, they took a positive view of mentor group discussions and of having a mentor, both essential components of the portfolio model described. Comparisons of BDS1 2004–5 and BDS2 2005–6 data suggest that students are becoming more comfortable with reflection. The data provide some limited encouragement that students are beginning to acquire the skills which will enable them to reflect purposefully in their professional lives, although it will be some years before this assertion can be substantiated.
Peer‐group assessment of pre‐clinical operative skills in restorative dentistry and comparison with experienced assessors
Authors: Satterthwaite J. D. , Grey N. J. A.
Published: April 2008

Objective:  In order to assess the feasibility of moving away from a tutor‐assessed summative assessment to a peer‐group marked assessment with more formative value, a study was undertaken to investigate if any differences existed between marks given by a peer group acting as examiner when compared with experienced assessors. The null hypothesis was that no differences in grades would exist between the examiners.

Methods:  A total of 130 ivorine teeth set in dentoform models (mounted in phantom heads) were prepared by undergraduate preclinical students. The prepared teeth were randomly allocated for assessment to one of six student groups who met and graded each tooth preparation. Notes on common errors were supplied together with a list of multiple exemplar grades (of the full range of grades) and associated comments, together with a list of grade descriptors (for the five‐point scale A–E) and a sectioned silicone index. The same preparations were independently assessed by two experienced restorative academic examiners using the same guidance.

Results:  The mean rank scores given by a Friedman test did not show any statistically significant difference (P = 0.531). Kappa scores for inter‐examiner agreement varied from 0.318 to 0.530.

Conclusions:  The data from the present study do not show any significant differences in grades awarded by experienced examiners to those awarded by a peer group. Peer‐group assessment may be useful to encourage a greater understanding of concepts and principles underlying the development of operative skills.
Melatonin restores impaired contractility in aged guinea pig urinary bladder
Authors: Gomez‐Pinilla Pedro J. , Gomez Maria F , Swärd Karl , Hedlund Petter , Hellstrand Per , Camello Pedro J. , Andersson Karl‐Erik , Pozo María J.
Published: April 2008

Abstract: Urinary bladder disturbances are frequent in the elderly population but the responsible mechanisms are poorly understood. This study evaluates the effects of aging on detrusor myogenic contractile responses and the impact of melatonin treatment. The contractility of bladder strips from adult, aged and melatonin‐treated guinea pigs was evaluated by isometric tension recordings. Cytoplasmatic calcium concentration ([Ca2+]i) was estimated by epifluorescence microscopy of fura‐2‐loaded isolated detrusor smooth muscle cells, and the levels of protein expression and phosphorylation were quantitated by Western blotting. Aging impairs the contractile response of detrusor strips to cholinergic and purinergic agonists and to membrane depolarization. The impaired contractility correlates with increased [Ca2+]iin response to the stimuli, suggesting a reduced Ca2+sensitivity. Indeed, the agonist‐induced contractions in adult strips were sensitive to blockade with Y27362, an inhibitor of Rho kinase (ROCK) and GF109203X, an inhibitor of protein kinase C (PKC), but these inhibitors had negligible effects in aged strips. The reduced Ca2+sensitivity in aged tissues correlated with lower levels of RhoA, ROCK, PKC and the two effectors CPI‐17 and MYPT1, and with the absence of CPI‐17 and MYPT1 phosphorylation in response to agonists. Interestingly, melatonin treatment restored impaired contractility via normalization of Ca2+handling and Ca2+sensitizations pathways. Moreover, the indoleamine restored age‐induced changes in oxidative stress and mitochondrial polarity. These results suggest that melatonin might be a novel therapeutic tool to palliate aging‐related urinary bladder contractile impairment.
Melatonin protects against endosulfan‐induced oxidative tissue damage in rats
Authors: Omurtag Gülden Z. , Tozan Ayfer , Şehirli Ahmet Özer , Şener Göksel
Published: April 2008

Abstract:  Endosulfan is a chlorinated cyclodiene insecticide which induces oxidative stress. In this study, we investigated the possible protective effect of melatonin, an antioxidant agent, against endosulfan (Endo)‐induced toxicity in rats. Wistar albino rats (n = 8) were administered endosulfan (22 mg/kg/day orally) followed by either saline (Endo group) or melatonin (10 mg/kg/day, Endo + Mel group) for 5 days. In other rats, saline (control group) or melatonin (10 mg/kg/day, Mel group) was injected for 5 days, following corn oil administration (vehicle of endosulfan). Measurement of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content were performed in liver and kidney. Furthermore, aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), and creatinine levels, lactate dehydrogenase (LDH) activity were measured in the serum samples, while tumor necrosis factor‐α (TNF‐α), interleukin‐β (IL‐β) and total antioxidant capacity (AOC) were assayed in plasma samples. Endosulfan administration caused a significant decrease in tissue GSH and plasma AOC, which was accompanied with significant rises in tissue MDA and collagen levels and MPO activity. Moreover, the proinflammatory mediators (TNF‐α and IL‐β), LDH activity, AST, ALT, creatinine and BUN levels were significantly elevated in the endosulfan‐treated rats. On the other hand, melatonin treatment reversed all these biochemical alterations induced by endosulfan. Our results suggest that oxidative mechanisms play an important role in endosulfan‐induced tissue damage and melatonin, by inhibiting neutrophil infiltration, balancing oxidant–antioxidant status and regulating the generation of inflammatory mediators, ameliorates oxidative organ injury as a result of endosulfan toxicity.
Coexpression of Wild‐type and Mutant Prion Proteins Alters Their Cellular Localization and Partitioning into Detergent‐resistant Membranes
Authors: Schiff Edwin , Campana Vincenza , Tivodar Simona , Lebreton Stéphanie , Gousset Karine , Zurzolo Chiara
Published: April 2008

Transmissible spongiform encephalopathies (TSEs) are a group of diseases of infectious, sporadic and genetic origin, found in higher organisms and caused by the pathological form of the prion protein. The inheritable subgroup of TSEs is linked to insertional or point mutations in the prion gene prnp, which favour its misfolding and are passed on to offspring in an autosomal‐dominant fashion. The large majority of patients with these diseases are heterozygous for the prnp gene, leading to the coexpression of the wild‐type (wt) (PrPC) and the mutant forms (PrPmut) in the carriers of these mutations. To mimic this situation in vitro, we produced Fischer rat thyroid cells coexpressing PrPwt alongside mutant versions of mouse PrP including A117V, E200K and T182A relevant to the human TSE diseases Gestmann–Sträussler–Scheinker (GSS) disease and familial Creutzfeldt–Jakob disease (fCJD). We found that coexpression of mutant PrP with wt proteins does not affect the glycosylation pattern or the biochemical characteristics of either protein. However, FRET and co‐immunoprecipitation experiments suggest an interaction occurring between the wt and mutant proteins. Furthermore, by comparing the intracellular localization and detergent‐resistant membrane (DRM) association in single‐ and double‐expressing clones, we found changes in the intracellular/surface ratio and an increased sequestration of both proteins in DRMs, a site believed to be involved in the pathological conversion (or protection thereof) of the prion protein. We, therefore, propose that the mutant forms alter the subcellular localization and the membrane environment of the wt protein in co‐transfected cells. These effects may play a role in the development of these diseases.
Fracture resistance and histological findings of immature teeth treated with mineral trioxide aggregate
Authors: Hatibović‐Kofman Šahza , Raimundo Lin , Zheng Lei , Chong Lawrence , Friedman Manfred , Andreasen Jens Ove
Published: April 2008

Abstract –  The objective of the present study was to test the hypothesis that the fracture strength of calcium hydroxide and mineral trioxide aggregate (MTA)‐filled immature teeth decreased over time. Immature mandibular incisors from sheep were extracted and the pulps were extirpated using an apical approach with a barbed broach, and the teeth were divided into three experimental groups. Group 1: untreated teeth. Group 2: the root canals were filled with calcium hydroxide paste. Group 3: the root canals were filled with MTA. All specimens were kept in saline with 1% antibiotics at 4°C for certain periods of time: 2 weeks, 2 months, and 1 year. Then they were tested for fracture strength in an Instron testing machine. The results were subjected to statistical analysis by the Tukey–Kramer tests. A P‐value (<0.05) was considered statistically significant. One tooth from each group was selected randomly for a histological study, examining matrix metalloproteinases (MMP2 and MMP14) and tissue inhibitor of metalloproteinase (TIMP). The results showed the mean fracture strengths decreased over time for all the three groups. Although the untreated teeth showed the highest value (45.5 MPa) at 2 weeks, the fracture strengths decreased significantly after 2 months (P < 0.05). On the other hand, the teeth treated with calcium hydroxide or MTA decreased, but not significantly over time (P > 0.05). For the MTA‐treated teeth, the fracture strengths were not found significantly different from the untreated or calcium hydroxide‐treated teeth at 2 weeks or 2 months (P > 0.05). However, the strength was significantly higher in the MTA group compared with the other two groups after 1 year (P < 0.05). Immunofluorescence images revealed expression of collagen type 1, MMP‐2 and MMP‐14 in both untreated and endodontically treated teeth. However, TIMP‐2 was only observed in the MTA‐treated teeth. In conclusion, the teeth with root treatment with MTA showed the highest fracture resistance at 1 year (P < 0.05). An explanation could be that MTA induced the expression of TIMP‐2 in the dentin matrix and thereby possibly prevented destruction of the collagen matrix.
Impact of treated and untreated dental injuries on the quality of life of Ontario school children
Authors: Fakhruddin Kausar Sadia , Lawrence Herenia P , Kenny David J , Locker David
Published: April 2008

Abstract –  A population‐based, matched case–comparison study was undertaken in 30 schools in two Ontario communities to measure the impact of dental trauma on quality of life (QoL) in Canadian school children. Dental hygienists screened 2422 children aged 12–14 years using the dental trauma index, the decayed, missing and filled teeth index (DMFT) and the aesthetic component of the index of orthodontic treatment needs (AC‐IOTN). Cases (n = 135) were children with evidence of previous dental trauma. Controls (n = 135) were classmates matched for age and gender. Oral‐health‐related QoL was assessed using mailed Child Perception Questionnaires (CPQ11‐14) completed by all children. Data were analyzed using simple and multiple conditional logistic regressions after adjusting for DMFT and AC‐IOTN, CPQ11‐14, overall impact and item‐specific impacts. Approximately 64% of injuries were untreated enamel fractures and just over 30% were previously injured restored teeth. Untreated children experienced more chewing difficulties (P = 0.026), avoided smiling (P = 0.029) and experienced affected social interactions (P = 0.032) compared with their non‐injured peers. When treated and non‐injured groups were compared, the only statistically significant effect was difficulty in chewing (P = 0.038). Injured children who were untreated experienced more social impact than their non‐injured peers. Restoration of injured teeth improved aesthetics and social interactions but functional deficiencies persisted as a result of periodontal or pulpal pain.
In vitro evaluation of casein phosphopeptide‐amorphous calcium phosphate as a potential tooth transport medium: viability and apoptosis in L929 fibroblasts
Authors: Cehreli S. Burcak , Gurpinar Aylin O. , Onur Ali M. , Dagli Fugen Tasman
Published: April 2008

Abstract –  Casein phosphopeptides (CPP) are derived from casein, which accounts for 80% of the total protein in bovine milk .The purpose of this in vitro study was to evaluate the potential use of a CPP‐amorphous calcium phosphate (CPP‐ACP) preparation as a transport medium for avulsed teeth. L929 fibroblastic cell line was plated in 24‐well culture plates. Following incubation, the cells were treated with 10−3, 10−4, 10−6, 10−8, 10−12 dilutions of a water‐based CPP‐ACP paste (Tooth Mousse, GC Corp., Tokyo, Japan). Untreated cells served as controls. The L929 cells were counted at the 1st, 3rd and 7th days. Propidium iodide/acridine orange staining was used to assess apoptosis of treated cells and of the positive control. For each concentration (dilution), statistical analysis of cell survival within time was performed using two‐way analysis of variance (anova, P = 0.05). One way anova and Tukey tests were applied to compare the effect of different concentrations on cell survival at each evaluation day (P = 0.05). Except for the 10−3and 10−4 dilutions, all groups demonstrated an increase in cell numbers at days 1 and 3, followed by a decrease at day 7. Irrespective of the increase or decrease in cell viability, time‐dependent changes for each dilution group were significantly different. Cells in the 10−3and 10−4 dilution groups demonstrated a rapid apoptotic response. A relatively few number of apoptotic cells were observed in the 10−6 and 10−8 dilution groups, while no sign of apoptosis was evident in the 10−12 dilution group and control. These results suggest that when highly diluted, the tested CPP‐ACP preparation may help preserve L929 cell viability in the short term without inducing apoptosis.
Oral health‐related quality of life in children: Part III. Is there agreement between parents in rating their children’s oral health‐related quality of life? A systematic review
Authors: Barbosa TS , Gavião MBD
Published: April 2008

Abstract:  Objective:  One issue that receives a great deal of attention is the comparison between measurement of children’s oral health‐related quality of life (OHRQoL) reports with those of their parents. However, the extent to which parents understand the effects of ill‐health on their children’s lives remains unanswered. The purpose of this systematic review was to identify the literature on the nature, extent and the pattern of agreement/disagreement between parent and child reports about child OHRQoL and assess the association between them.

Materials and methods:  The literature was searched using MEDLINE, ISI, Lilacs and Scielo, from January 1985 to March 2007. The selected studies used well‐validated instruments and provided children’s and parent’s perceptions of child OHRQoL.

Results:  A total of 87 articles were retrieved and five were selected for the review, which showed that children and parents do not necessarily share similar views about child OHRQoL. Some parents may have limited knowledge about their children’s OHRQoL, particularly the impact on social and emotional well‐being.

Conclusions:  Valid and reliable information can be obtained from parents and children using appropriate questionnaire techniques. Although the parents’ reports may be incomplete due to lack of knowledge about certain experiences, they still provide useful information.
Oral health‐related quality of life in children: Part I. How well do children know themselves? A systematic review
Authors: Barbosa TS , Gavião MBD
Published: April 2008

Abstract:  Objective:  Paediatric oral disorders are likely to have a negative effect on the quality of life. Until recently, children’s oral health‐related quality of life (OHRQoL) was measured using parents as informants. Instruments have now been developed, which have demonstrated that with appropriate questionnaire techniques, valid and reliable information can be obtained from children. The aim of this study was to make a systematic review of the existing literature about child perceptions of OHRQoL and their validation.

Methods:  A computerized search was conducted using Medline, ISI, Lilacs and Scielo for children’s perception of OHRQoL. The inclusion criteria were: the articles should contain well‐validated instruments and provide child perceptions of OHRQoL.

Results:  From 89 records found, 13 fulfilled the criteria. All studies included in the critical appraisal of the project suggested good construct validity of overall child perceptions of OHRQoL. However, children’s understanding of oral health and well‐being are also affected by variables (age, age‐related experiences, gender, race, education, culture, experiences related to oral conditions, opportunities for treatment, childhood period of changes, back‐translating questionnaire, children self‐perceived treatment need).

Conclusions:  The structure of children’s self‐concept and health cognition is age‐dependent as a result of their continuous cognitive, emotional, social and language development. By using appropriate questionnaire techniques, valid and reliable information can be obtained from children concerning their OHRQoL.
The effectiveness of a novel optical probe in subgingival calculus detection
Authors: Kasaj A , Moschos I , Röhrig B , Willershausen B
Published: April 2008

Abstract:  Objectives:  The aim of the present study was to evaluate the effectiveness of a novel optical calculus detection system under in vivo conditions.

Methods:  One hundred and seventy‐six tooth surfaces from 44 adult teeth that were indicated for extraction were selected for the present study. The patients were randomly assigned to one of the two experimental groups. In group A (n = 96), clinical presence or absence of subgingival calculus deposits was determined using the light‐emitting diode‐based optical probe (OP). In group B (n = 80), the subgingival deposits were first recorded with the OP followed by root surface debridement until no subgingival deposits could be detected by the device. Teeth were then extracted and examined under a stereomicroscope by two trained dentists (DENT 1, DENT 2) and a dental student. Results were compared with the measurements of the OP and direct visual control.

Results:  In group A, post‐extraction results revealed 89% and 90% agreement with the positive and negative OPs detection. In group B, 17% of the surfaces demonstrated even after subgingival debridement and control with the detecting device still calcified deposits in the microscopic evaluation. The highest inter‐examiner agreements were observed between DENT 1 and DENT 2.

Conclusion:  It was shown that the optical detection system identifies subgingival calculus with a high efficacy and therefore, may be a support for the operator to determine the endpoint of root surface instrumentation.
Effects of fixed orthodontic appliances on subgingival microflora
Authors: Ristic M , Svabic M Vlahovic , Sasic M , Zelic O
Published: April 2008

Abstract:  Objectives:  Fixed orthodontic appliances cause plaque accumulation around bands and brackets. Since the microbiological composition of dental plaque is closely connected to periodontal tissue health, the aim of this study was to determine the effects of fixed orthodontic appliances on subgingival microflora and periodontal status.

Methods:  This prospective study was carried out on 32 adolescents scheduled for fixed orthodontic treatment. Subgingival dental plaque samples and periodontal records (pocket probing depth and clinical attachment level) were obtained in four recording times: before bonding of fixed appliances (T0), 1 (T1), 3 (T2) and 6 (T3) months after the beginning of orthodontic therapy, in order to detect the changes in periodontopathic anaerobe microbial flora and its effects on periodontal status.

Results:  The values of pocket probing depth, total number of microorganisms and number of patients with positive findings of Prevotella intermedia and other periodontopathic anaerobes increased from T0 to the maximum obtained in T2 recording time. Both clinical and microbiological values decreased 6 months after the beginning of orthodontic therapy.

Conclusions:  The therapy with fixed appliances may transitionally increase the growth of periodontopathogenic bacteria and consequently result in gingival inflammatory response but without destructive effect on deep periodontal tissues.
Scleroderma: considerations for dental hygienists
Authors: Tolle SL
Published: April 2008

Abstract:  Scleroderma, the general name of a group of progressive diseases affecting the connective tissues is the most deadly of the varying connective tissue disorders. Characterized by abnormal thickening of the skin, this collagen‐vascular disease is associated with immune dysfunction. Hallmark signs of scleroderma include fibrosis, vascular instability and initial inflammation resulting from excessive collagen deposition. Oral facial involvement is considerable, necessitating adaptations in patient oral self‐care and influencing oral hygiene. Appropriate dental hygiene management of patients with this autoimmune disorder requires an understanding of clinical characteristics, the recognition of oral facial involvement, treatment considerations and pharmacological interventions. With this information, dental hygienists will be better prepared to provide compassionate, safe and effective dental hygiene management and care to patients with scleroderma.
Study of oral changes in patients with eating disorders
Authors: Lifante‐Oliva C , López‐Jornet P , Camacho‐Alonso F , Esteve‐Salinas J
Published: April 2008

Abstract:  Background:  The prevalence of eating disorders is very high in industrialized countries, especially in young women. The principal orodental manifestations are erosion of the dental enamel, caries and dental sensitivity.

Objectives:  Our aim was to study oral complications in female with eating disorders.

Methods:  We study oral complications (dental, mucosal and salivary) in 17 female patients from the Hospitalized Patients Eating Disorders Unit.

Results:  We found alterations in salivary flow and pH, as well as salivary gland enlargement.

Conclusions:  A significant alteration in oral tissue occurs; this has an adverse impact on oral health, producing an accumulation of local irritants which favour the appearance of oral diseases. Preventative measures are therefore recommended for this group of patients.
Complex regional pain syndrome type I in children
Authors: Tan Edward CTH , Zijlstra Basil , Essink Marlou L , Goris R Jan A , Severijnen René SVM
Published: April 2008

Background: Complex Regional Pain Syndrome type I (CRPS I) is a potentially incapacitating syndrome which can occur after a minor injury or operation to a limb. It is a disorder characterized by pain, sensory and motor disturbances. CRPS I is well known in adults, but a relatively new diagnostic entity in children. The clinical presentation of CRPS I in children is, to some extent, different from adults and therefore sometimes not recognized early. The aim of this study was to search for differences in patient characteristics between children and adults with CRPS I.

Methods: We have performed a retrospective chart review of 78 children (age ≤16 year) with CRPS I and compared the data with those of 951 adults with CRPS I.

Results: The child population consisted predominantly of girls and older children (median age 13 years). The child population differed from adults in that the skin temperature of the involved extremity at onset was more often cooler, the lower extremity was involved more frequently and neurological and sympathetic symptoms were less pronounced.

Conclusions: In several aspects, CRPS I in children has a different presentation than in adults.
Collective behavior in gene regulation: Metabolic clocks and cross‐talking
Authors: Bianchi Michele M.
Published: April 2008

Biological functions governed by the circadian clock are the evident result of the entrainment operated by the earth’s day and night cycle on living organisms. However, the circadian clock is not unique, and cells and organisms possess many other cyclic activities. These activities are difficult to observe if carried out by single cells and the cells are not coordinated but, if they can be detected, cell‐to‐cell cross‐talk and synchronization among cells must exist. Some of these cycles are metabolic and cell synchronization is due to small molecules acting as metabolic messengers. We propose a short survey of cellular cycles, paying special attention to metabolic cycles and cellular cross‐talking, particularly when the synchronization of metabolism or, more generally, cellular functions are concerned. Questions arising from the observation of phenomena based on cell communication and from basic cellular cycles are also proposed.
Collective behavior in gene regulation: The cell is an oscillator, the cell cycle a developmental process
Authors: Klevecz Robert R. , Li Caroline M. , Marcus Ian , Frankel Paul H.
Published: April 2008

The finding of a genome‐wide oscillation in transcription that gates cells into S phase and coordinates mitochondrial and metabolic functions has altered our understanding of how the cell cycle is timed and how stable cellular phenotypes are maintained. Here we present the evidence and arguments in support of the idea that everything oscillates, and the rationale for viewing the cell as an attractor from which deterministic noise can be tuned by appropriate coupling among the many feedback loops, or regulons, that make up the transcriptional–respiratory attractor cycle. The existence of this attractor also explains many of the dynamic macroscopic properties of the cell cycle and appears to be the timekeeping oscillator in both cell cycles and circadian rhythms. The path taken by this primordial oscillator in the course of differentiation or drug response may involve period‐doubling behavior. Evidence for a relatively high‐frequency timekeeping oscillator in yeast and mammalian cells comes from expression array analysis, and GC/MS in the case of yeast, and primarily from macroscopic measures of phase response to perturbation in the case of mammalian cells. Low‐amplitude, genome‐wide oscillations, a ubiquitous but often unrecognized attribute of phenotype, may be a source of seemingly intractable biological noise in microarray and proteomic studies. These oscillations in transcript and protein levels and the repeated cycles of synthesis and degradation they require, represent a high energy cost to the cell which must, from an evolutionary point of view, be recovered as essential information. We suggest that the information contained in this genome‐wide oscillation is the dynamic code that organizes a stable phenotype from an otherwise passive genome.
SEX PHEROMONE COMPONENTS OF THE OREIENTAL TOBACCO BUDWORM, HELICOVERPA ASSULTA GUENÉE: IDENTIFICATION AND FIELD TRIALS
Authors: Liu Mengying , Cai Jianping , Tian Yu
Published: April 2008

Abstract  The sex pheromone gland extracts of the Oriental tobacco budworm, Helicover assulta Guenée, collected from North China in Beijing area, were analyzed by capillary gas chromatograph(GC) and 6 components from the extracts were identified by capillary GC—MS as hexadecanal (16:Ald), (Z)9‐hexadecenal (Z9–16:Ald), (Z)‐11‐hexadecenal (Z11–16:Ald), (Z)‐9‐hexadecen‐1‐ol (Z9–16:OH), Z11‐hexadecen‐1‐ol (Z11–16:OH), Z‐9‐hexadecenylacetate (Z9–16:OAc) at a ratio of 10. 9: 58. 7: 3. 9: 14. 7: 1.1: 10. 7. Field studies indicated that an optimum blend of Z9–16:Ald and Z11–16:Ald was 100: 7. Addition of 16: Ald or Z9–16:Ac to the two aldehyde blend showed no significant effect on attractiveness. However presence of Z9–16:OH in the blends significantly reduced male captures.
QUANTITATIVE VARIATION OF ECDYSTEROIDS OF IXODID TICKS
Authors: Jiang Zaijie , Wu Qing , Yun Zihou , Shi Wenqing
Published: April 2008

Abstract  In order to explore the role of ecdysteroids in development and reproduction of ixodid ticks, we studied the quantitative variation of ecdysteroids in the hemolymph, synganglion, ovary and whole body of the female ixodid ticks, Dermacentor niveus and Haemaphysalis longicornis, before and after engorgement and oviposition by HPLC and RIA. The ecdysteroid content in eggs of these ticks was determined by HPLC. The results indicated that before engorgement the quantitative variation of ecdysteroids in the whole female body was not significant, but their levels increased rapidly after engorgement. The ecdysteroid titer in hemolymph was peaked on the 5th day after engorgement, which was one day prior to oviposition. It may be regarded as a singnal of oviposition. In the synganglion the peak of ecdysteroid level occurred also on the 5th day after engorgement. This is coincident with the secretory activity of neurosecretory cells of synganglion. From the 3rd day after engorgement until oviposition the ecdysteroid level in the ovary increased rapidly. Ecdysteroids were detected in eggs of H. longicornis too. They stem from ovary and accumulated with the process of embryonic development.
NOTES ON A NEW GENUS AND SPECIES OF SYRPHIDAE FROM CHINA (INSECTA: DIPTERA)
Authors: Li Qingxi
Published: April 2008

Abstract  In this paper, a new genus, Pseudomeromacrus and new species, Pseudamermacrus seti fenitus Li, is described. All type specimens are deposited in South China Agricultural University.
FORAGE LOSSES CAUSED BY GRASSHOPPER CHORTHIPPUS DUBIUS (ZUB.1 ON GRASSLAND IN INNER MONGOLIA OF CHINA
Authors: Qiu Xinghui , Li Hongchang , Fan Weimin
Published: April 2008

Abstract  To quantitatively assess the losses of forage, we conducted experiments to determine the average amount of forage destroyed (forage consumed plus forage cut‐off and dropped to the ground) per day by the grasshopper, Chorthippus dubius (Zub.), at its different life stages in laboratory and then extrapolated estimates of losses caused by the field grasshopper population from these results and the population densities of this grasshopper. The main results are as follows:

 Ch. dubius is a late‐occurring species of grasshoppers in Inner Mongolian grassland. It occurred from June to October. The duration for each instar and the longevity of the adult under natural conditions ranged from 9. 09–9. 81 fdays) and 17. 65–19. 441days) respectively.

 Both consumption and forage defoliation rates by Ch. dubius increase with its developemnt. The consumption rates had significantly linear relationships with the grasshopper's body weights.

 Average losses caused by one grasshopper in its whole lifespan were 487. 55–784. 4 mg (dry weight) and the average amount of forage consumed and wasted per day was 7. 64–11. 45 mg.

 Total losses caused by Ch. dubius population in 1990 ranged from 0. 762–1. 647 g/m2 in the three types of vegetation, and the largest value was found in restorative type. The seasonal courses of cumulative forage losses would fit logistic equations in the three vegetation types.

 Population densities (18. 5, 194., 11. 8/m2, 4th instar nymph predominantly) were suggested as the levels at which control should be initiated on the three types of pastures respectively.
TWO NEW SPECIES OF THE GENUS CYBOCEPHALUS FROM CHINA (COLEOPTERA: CYBOCEPHALIDAE)
Authors: Tian Mingyi , Yu Guoyue
Published: April 2008

Abstract  Two species. Cybocephalus flavicapitus and C. undatus (Coleoptera: Cybocephalidae), are recorded as new to science in this paper. The type specimens are preserved in the Insects Collection of South China Agricultural University.
THE EFFECTS OF LAGENIDIUM GIGANTEUM ON AEDES ALBOPICTUS AND OTHER MOSQUITOES IN GUIZHOU, CHINA
Authors: Su Xiaoqing
Published: April 2008

Abstract  The mosquito fungal pathogen, Lagenidium giganteum, was used to kill mosquito larvae of Guizhou. China, in the laboratory. The infection rates in Aeds albopictus ranged 25–89%, while those in Culex quingue fasciatus 90–100%. Five additional species and one genus of mosquitoes were added to the host list of L. giganteum.
A NEW EULOPHID PARASITIZING LITCHI GALL MIDGE FROM CHINA (HYMENOPTERA: CHALCIDOIDEA)
Authors: Yang Zhongqi , Luo Qihao
Published: April 2008

Abstract  Mangocharis litchii sp. nov. is described from south China as a parasitoid of Mayetiola sp. on leaf of litchi tree. The gall midge is a serious pest of the fruit tree in south China. The biology of the new chalcidoid is also dealt with. The genus Mangocharis is new to China.
TWO NEW SPECIES OF STICK INSECTS FROM XIZANG AUTONOMOUS REGION (PHASMATODEA: PHASMATIDAE, HETEKONEMIIDAE)
Authors: Chen Shuchun , He Yunheng
Published: April 2008

Abstract  This paper deals with two new species of Phasmatodea from the Xizang Aut. Reg. belonging to Phasmatidae and Heteronemiidae. Their comparisons with close species and figures of characteristics are given.
DETECTION OF RICKETTSIA TSUTSUGAMUSHI FROM VECTOR TROMBICULID MITE BY DNA AMPLIFICATION USING POLYMERASE CHAIN REACTION TECHNIQUE*
Authors: Li Jiacan , Zheng Xiaoying , Ni Hong , Chen Tiansheng
Published: April 2008

Abstract  With reference to the Sta 58 major antigen gene of Rickettsia tsutsugamushi (Karp strain), we had designed and synthesized a pair of DNA primers; and a kilobase fragment of Sta 58 is amplified for using in polymerase chain reaction (PCR) with the primers.

This is the first report on detection of R. tsutsugamushi in trombiculids by using PCR technique. The experimental results indicated that the time for which R. tsutsugamushi could exist in the adult of Leptotromhidium deliense when inoculated into its abdomenal cavity was 360 days at least and R. tsutsugamushi could be transovarially transmitted to the offsprings for 4 generations; and the time for which R. tsutsugamushi could exist in L. deliense after biting the infective mouse was 270 days at least and R. tsutsugamushi could be transmitted transovarially to the offsprings for 2 generations. The results also showed that the PCK technique was highly specific and sensitive for detection of R. tsutsugamushi; and the amplification of gene outside body to detect the rickettsiae in the body of trombiculid and mouse can be used as a new method for investigation of scrub typhus epidemiology.
NEUROANATOMICAL STUDIES OF PROTHORACIC GLANDS OF COTTON BOLLWORM HELZCOVERPA ARMZCERA (LEPIDOPTERA: NOCTUIDAE)*
Authors: Zhao Faqing , Carlson Stanley D.
Published: April 2008

Abstract Gross anatomy, ultrastructure, innervation and ultrastructural alterations of the prothoracic gland (PTG) of cotton bollworm, Helicover pa armigera (Lepidoptera: Noctuidae) are illustrated for the last larval and early pupal stages as observed by light and electron microscopy. The T‐shaped, paired (PTGs) consist each of 76–116 cells which are classified morphologically as large and small gland cells. In addition, another kind of small (about 6μ in diameter) gland cell was found in the PTGs of last instar larvae. The PTGs are innervated by the branches of 3 nerves! and tracheae and tracheoles are abundantly distributed to these glands. PTGs disappeared completely by the third day after ecdysis to the pupal stage (at temperature 28 C with a photoperiod L15:D9). An intercellular channel system (ICS) is formed by numerous, deep invaginations of the plasma membrane of gland cells. This ICS gradually increases in depth and width and reaches maximum development around the time of the major ecdysteroid secretion peak during the last larval instar.

Numerous multivesicular sacs (MVS) with their remnants and an extensive rough endoplasmic reticulum were observed within ICS and cytoplasm, respectively, on the fourth day of the last larval instar. At that time the matrix of mitochondria became much more electron lucent.

Freeze‐fracture replicas of the glandular epithelium were made from last instar (4th day larvae. Dynamics of structure are related to data from others concerning secretory states of the prothoracic glands of this species.
INFLUENCE OF SUBLETHAL EFFECTS OF INSECTICIDES ON THE POPULATION DYNAMICS OF PLUTELLA XYWSTELLA AND ITS PARASITOID DIADEGMA EUCEROPHAGA IN THE FIELD
Authors: Gu Dejiu , Wright D. J. , Waage J. K.
Published: April 2008

Abstract The larvae of Plutella xylostella feeding on cabbage plants treated by insecticides, nomolt (25 ×10‐6 and cypermethrin (20× 10‐6 were exposed to their parasitoid, Diadegma euerophaga in the field. The life table technique and the control efficiency (CE) were used to evaluate the sublethal effects of insecticides on the population dynamics of P. xylostella and D. euerophaga. The results showed that the CEs of nomolt and cypermethrin on D. eucerophaga were bigger than that on P. xylostella. Nomolt had a profound effects on D. eucerophaga by the food chain.
FORECASTING GYPSY MOTH DEFOLIATION WITH A GEOGRAPHICAL INFORMATION SYSTEM
Authors: Zhou Guofa , Liebhold Andrew M.
Published: April 2008

AbstractIn this study, we developed a series of logistic regression models for forecasting gypsy moth defoliation. The models were parameterized by using data collected over a small scaled 100m× 100m gridarea; the independent variables included egg mass density, male moth trap, previous year defoliation, and distance to the nearest cell which was defoliated in the previous year. We simulated the decision‐making by using these models; this method essentially simulated the application of current gypsy moth management decision‐making. The results indicated that these models can be more reliably applied to actual management decision.