bluuebunny/crossref_metadata_2025 huggingface dataset:
Tuberaphis owadai (Homoptera), a new aphid species forming a large gall on Styrax tonkinensis in northern Vietnam
Authors: KUROSU Utako , AOKI Shigeyuki
Published: June 2003

Tuberaphis owadai sp. nov., an aphid species forming coral‐shaped galls on Styrax tonkinensis in northern Vietnam, is described. We found that the species produces many sterile second‐instar soldiers in the gall. The colony size of a large gall was estimated to be 178 000, approximately half of which were soldiers. Alates emerging from galls contained sexual embryos, indicating that the life cycle is monoecious (non‐host‐alternating). Predaceous larvae of the pyralid moth Assara seminivalis were found in several galls.
Fungus gnats of the genera Anatella, Allodia and Cordyla in Japan (Diptera: Mycetophilidae)†
Authors: SASAKAWA Mitsuhiro , ISHIZAKI Hironori
Published: June 2003

Six new mycetophilid species from three genera belonging to the tribe Exechiini are described: Anatella prominens on a fungus of the Polyporaceae, Allodia bipexa and Allodia conifera on fungi of the Russulaceae, Allodia quadrata on fungi of the Hygrophoraceae, Tricholomataceae, Rhodophyllaceae, Russulaceae and Fistulinaceae, Allodia laccariae on a fungus of the Tricholomataceae, and Cordyla bidenticulata on a fungus of the Boletaceae. Their characteristic male genitalia are illustrated. Cordyla flaviceps Staeger, Cordyla fusca Meigen and Cordyla pusilla Edwards are newly recorded from Japan.
No relationship between range size and germination niche width in the UK herbaceous flora
Authors: Thompson K. , Ceriani R. M.
Published: June 2003

It is widely assumed that species with broad niches will be commoner (have larger ranges) than species with narrow niches, but attempts to demonstrate this in plants and animals have generally been unsuccessful.

We used seasonal seedling emergence data to define the width of one important niche axis for 175 UK herbaceous species. We then compared niche width with UK range, using species as independent data points and also phylogenetically independent contrasts.

We found no evidence of any relationship between niche width and range. Possible reasons for this are: (i) mature plant traits are more important than seedling emergence in determining plant ranges; and (ii) ranges of most plants are strongly dispersal‐limited.
Survival, the hormonal stress response and UV‐B avoidance in Cascades Frog tadpoles (Rana cascadae) exposed to UV‐B radiation
Authors: Belden L. K. , Moore I. T. , Mason R. T. , Wingfield J. C. , Blaustein A. R.
Published: June 2003

Despite the increasing occurrence of global environmental changes, including increases in ultraviolet‐B radiation (UV‐B; 280–320 nm), little is known about how factors such as UV‐B affect animals physiologically. Amphibians provide a good model for examining physiological effects of UV‐B exposure because studies documenting both lethal and sub‐lethal effects have been completed on many species.

This study examines survival and the hormonal stress response, as measured by whole body levels of the glucocorticoid hormone corticosterone, of Cascades Frog, Rana cascadae, tadpoles exposed to ambient UV‐B in the field for either 7 or 42 days.

There were no differences in corticosterone levels between UV‐B exposed and non‐exposed tadpoles at either time point. However, after 42 days, survival was significantly higher in tadpoles shielded from UV‐B.

A stress response profile performed in the field demonstrated that young R. cascadae tadpoles are able to respond to confinement stress with increasing corticosterone. In addition, results from UV‐B avoidance tests suggest that R. cascadae tadpoles do not avoid UV‐B.

Thus, R. cascadae tadpoles may not perceive UV‐B radiation, which would explain why they do not respond hormonally to exposure, despite the potential for exposure to result in mortality.
A safe method of deflating ovarian cysts in a bag at laparoscopy
Authors: Montella Fabio , Balanikos Panos , Scott Peter , Magos Adam
Published: June 2003

Objective To describe a novel technique to drain a cyst in a bag at laparoscopic oophorectomy/cystectomy to reduce the incidence of bag rupture and intra‐peritoneal spillage of the cyst contents.

Setting An undergraduate teaching hospital.

Subjects Six women undergoing laparoscopic surgery for ovarian cysts.

Design Prospective observational study.

Materials and Methods We used the sterile plastic wrapping of the disposable suction/irrigation tubing as the bag. The bag is inserted via the 10 mm camera port by rolling it onto the blunt probe. The specimen is put into the bag either prior to surgery (for ovarian cystectomy) or after excision (for oophorectomy). The opening of the bag is then pulled out through the left ancillary port incision. To drain and debulk the cyst, a blunt probe is put into the bag and a valveless cannula rail‐roaded over the probe. The probe is removed and a Veress needle pushed down the cannula and into the cyst under direct laparoscopic vision. The cyst is drained and the bag removed either via the incision or a posterior colpotomy.

Results This technique was used on six patients. In all cases the bag remained intact with no spillage of ovarian contents.

Conclusion This technique reduces the chance of cyst content spillage during drainage at laparoscopic oophorectomy/cystectomy while avoiding the need to use expensive disposable laparoscopic bags.
Cervical and vaginal burn following hydro thermablation
Authors: Roberts Catharine , Hill Nicholas
Published: June 2003

Objective To highlight a potential complication of hydro thermablation, an ablative procedure designed to be easy to learn and safe to perform.

Design Case report.

Setting A district general hospital.

Conclusion Adequate training and strict attention to surgical technique is absolutely necessary to prevent further untoward incidents occurring during this otherwise simple and effective procedure.
Laparoscopic extirpation of bilateral rudimentary horns in a patient with a variant of Mayer–Rokitansky–Kuster–Hauser syndrome
Authors: Dokmeci Fulya , Atabekoglu Cem S. , Berker Bulent , Sonmezer Murat , Kabukcu Cihan
Published: June 2003

Objective To report a case of laparoscopic resection of bilateral rudimentary horns in a patient with a variant of Mayer–Rokitansky–Kuster–Hauser (MRKH) syndrome.

Methods The clinical records of the patient were reviewed.

Results Laparoscopy was undertaken in our patient for diagnosis of suspicious adnexal masses which had been observed on ultrasound examination. Laparoscopy disclosed two Müllerian remnants (bilateral rudimentary horns) on each pelvic sidewall and a simple paraovarian cyst 3–4 cm in size. These remnants did not communicate with each other and cervical agenesis was identified. It was decided to undertake bilateral laparoscopic horn resection since our patient complained of a cyclic pelvic pain and suspicious endometriotic implants on the right ovary and fallopian tube were observed; this was performed without complication. The resected horns and paraovarian cyst were removed by use of an endobag with extension of the left 5‐mm trocar incision. The patient was completely free of symptoms at the 1‐ and 6‐months follow‐up examinations.

Conclusion Laparoscopic resection was used safely for the treatment of a variant of MRKH syndrome with bilateral rudimentary horns.
Hysterectomy: towards an overnight stay
Authors: Trehan A.K.
Published: June 2003

Objective To review the introduction of an overnight stay laparoscopically assisted vaginal hysterectomy (LAVH) service in a district general hospital.

Design A retrospective study.

Setting Dewsbury District Hospital is a 478‐bedded district general hospital with 14 gynaecological inpatient beds, serving a population of 165 000.

Data collection Included in the study were 265 consecutive patients who underwent LAVH, performed by one consultant between September 1995 and September 2000. These patients were unsuitable for vaginal hysterectomy according to conventional (British) criteria and in the past would be have been offered abdominal hysterectomy. The names of the patients were obtained from the hospital register. All operative notes were abstracted and data collected independently by junior medical staff working in the department.

Results Postoperative stay was analysed for consecutive groups of 50 patients. Initially the median postoperative stay was 2 nights but by the last cohort, nine out of 10 patients were going home after only 1 night's postoperative stay. None of the patients were readmitted or suffered complications as a result of this policy. Among the patients, 4.5% suffered one or more complications (most were minor). No patient suffered visceral injury. Patients had full surgical recovery by 6 weeks after operation except for a few who developed granulation tissue which needed topical treatment.

Conclusion In experienced hands LAVH has few complications, and it is acceptable and safe to discharge patients home after an overnight hospital stay provided strict guidelines are followed.
Haematosalpinx and haematometra as long‐term complications of balloon endometrial ablation
Authors: Sinha P. , Pachydakis A. , Konamme S.P. , Auld B.
Published: June 2003

Objective To report the case histories of two patients who presented with haematometra and haematosalpinx 18 and 24 months after endometrial ablation.

Design This is a retrospective case note analysis.

Subjects A 51‐year‐old woman, who had undergone endometrial ablation 18 months previously, presented with acute abdominal pain. She was known to be taking continuous combined hormone replacement therapy. Pelvic ultrasound scan showed a large cystic mass, and diagnostic laparoscopy revealed a right haematosalpinx. She underwent right salpingectomy and was pain‐free after the operation. A 48‐year‐old woman presented with lower abdominal pain 2 years after endometrial balloon ablation. The ultrasound scan of the pelvis showed a haematometra (4.4 × 2.6 × 3.3 cm). She underwent examination under anaesthesia (EUA), dilation and drainage of the haematometra. A few weeks later she had a recurrence and underwent hysterectomy.

Conclusion As more ablation procedures are performed, more delayed complications will arise.
Colouterine fistula as a complication of colonic diverticulitis: a conservative approach
Authors: Al Azzam Mo’iad , Cassidy Laura , Thomas Millicent
Published: June 2003

Colouterine fistula is a rare complication of diverticular disease. Few cases have been reported in the literature. A wide spectrum of presentations may accompany this entity. In our experience it simulated uterine perforation at time of surgery. Diagnosis was confirmed by histopathology. Surgery has been suggested to be the treatment of choice in this situation, with resection of the colon as the main step; hysterectomy is mandatory to extirpate the sinus of infection. We undertook a conservative approach in this patient and did a simple repair of the colon. Hysterectomy was carried out. We believe that this would be a safe alternative to resection of the colon.
Laparoscopic management of ectopic pregnancy by trainees in Wales
Authors: Myerson Nicholas A. , Pugh David H.O.
Published: June 2003

Objective To discover whether trainees in Wales are able to manage ectopic pregnancy using laparoscopic techniques, and to identify factors preventing trainees from acquiring and using these skills.

Design Postal questionnaires.

Setting Wales deanery of the Royal College of Obstetricians and Gynaecologists.

Subjects All specialist registrars in obstetrics and gynaecology.

Results Two surveys were completed. The initial survey in January 2000 had a response rate of 91% and found that 38% of trainees could independently manage an ectopic pregnancy laparoscopically. A more detailed survey in January 2002 with an 87% response rate found that 21% of trainees were able to manage an ectopic pregnancy laparoscopically. However, only 7% of specialist registrars in years 1–3 of training could do so. The main reasons why trainees could not manage ectopic pregnancies laparoscopically were lack of practical experience coupled with a lack of consultant supervision.

Conclusions Over 2 years, there was a decrease in the number of trainees able to manage an ectopic pregnancy using laparoscopic techniques. This has important implications both for training and service provision.
Semi‐open direct trocar insertion method for induction of pneumoperitoneum at laparoscopy
Authors: Volpi Eugenio , Sismondi Piero
Published: June 2003

Background and objective Different techniques have been previously described for the induction of pneumoperitoneum to start laparoscopy. This is the first description of a technique of semi‐open direct trocar insertion in which the peritoneum is first opened and a trocar is then directly inserted without insufflation.

Patients and methods The technique was tested in 184 (89.3%) out of 206 patients who underwent laparoscopy at our institution over a 1‐year period. In 22 patients, closed entry through Palmer's upper quadrant with a Veress needle was used. An incision was made at the deepest point of the umbilical scar down to the peritoneal membrane which was entered to a depth of 1–2 mm. Direct trocar insertion was then performed.

Results Direct trocar insertion was successful in 171 (92.9%) patients at the first attempt, and in 183 out of 184 (99.4%) by the third attempt. The approach was changed to upper quadrant entry in only one patient. The technique was faster and easier than upper quadrant entry. No major complication was observed.

Conclusions Semi‐open direct trocar insertion can be performed safely in the starting phase of laparoscopy.
Laparoscopic surgery and adhesiolysis
Authors: Mettler L. , Schollmeyer T. , Kotdawala P. , Zavala A. , Moharram A.E.
Published: June 2003

Objectives To evaluate the degree of adhesion formation at laparoscopic surgery in different patient groups.

Design A retrospective study using the American Fertility Society's Adhesion Scoring Method and the MCASM (More Comprehensive Adhesion Scoring Method).

Subjects The 465 patients with adhesions among 2124 patients who underwent laparoscopy.

Results Details of the 465 cases of adhesiolysis are given. In subgroup 1 (n = 34) there were no pre‐existing adhesions. All 34 patients were assessed for adhesion occurrence at a second‐look laparoscopy after 6–8 weeks; 29.4% were found to have no adhesions and 70.6% of patients had significant or mild adhesions. A more comprehensive adhesion scoring method (MCASM) was found to be more objective in the assessment of adhesions; however, it was difficult to record in an easily readable manner. In subgroup 2, 21 patients who had undergone previous surgery for adhesiolysis were operated upon again, and 24% revealed an increased adhesion score, 57% the same adhesion score and 19% a reduced adhesion score at second‐look laparoscopy.

Conclusions The new data confirmed our previous knowledge: to avoid adhesions one must avoid surgery. If surgery has to be performed, laparoscopic surgery causes fewer adhesions than laparotomy.
Laparoscopic extracorporeal cystectomy in the management of large dermoid cysts
Authors: Sönmezer Murat , Güngör Mete , Cengiz Bora , Ortaç Fırat
Published: June 2003

Objective To evaluate the results of the surgical management of large dermoid cysts by laparoscopic extracorporeal cystectomy.

Design The results of the surgical management by laparoscopic extracorporeal cystectomy of large (≥8 cm) dermoid cysts in 21 women, were evaluated in a retrospectively designed study.

Setting Ankara University School of Medicine, Obstetrics and Gynaecology Clinic.

Intervention After the cyst had been aspirated and decompressed, it was pulled out through the trocar site, the 10‐mm suprapubic trocar incision having been enlarged to 25 mm. The aim of this was better identification of functional ovarian tissue and extracorporeal completion of cystectomy. The remaining ovarian tissue, that appeared to be functional, was pushed back into the peritoneal cavity. The duration of hospitalization, operating time, intraoperative blood loss and postoperative morbidity were evaluated.

Results All of the large cysts were managed successfully by laparoscopic extracorporeal cystectomy. The mean age of the patients was 28.5 ± 4.9 years (range 21–37). The mean diameter of the cysts was 11.2 ± 2.7 cm (range 8–17 cm), the mean operation time was 65.8 ± 13.9 min (range 45–95 min), and the mean duration of hospitalization was 1.8 ± 0.7 days (range 1–3 days). Average blood loss was less than 35 ml. Despite considerable efforts to keep leakage of cyst contents to a minimum, this did occur to some extent and was managed successfully by copious lavage in all patients. None of the patients developed postoperative morbidity associated with chemical peritonitis.

Conclusion Laparoscopic extracorporeal cystectomy is a safe and effective technique in the management of large dermoid cysts. Functional ovarian tissue could be well identified and preserved by direct visualization.
A European survey of the complications of a uterine thermal balloon ablation system in 5800 women
Authors: Rogerson Lynne , Duffy Sean
Published: June 2003

Objective To study the nature and incidence of complications, and the ease of use associated with a uterine thermal balloon system.

Design An anonymous postal questionnaire with no follow up for non‐responders.

Setting European survey throughout the UK, France, Switzerland and the Netherlands.

Sample All users of the ThermaChoice uterine thermal balloon system in the countries stated.

Main outcome measures These were the number of procedures performed by respondents throughout Europe; the nature and incidence of intraoperative and postoperative complications, and the perceived ease of use and safety of the thermal balloon system.

Results 446 questionnaires were mailed, and there were 149 responses (33.4%). From the returned questionnaires it is possible to report on an estimated 5859 procedures performed throughout Europe. In this series, there were 14 reported intraoperative complications (0.24%), two emergency procedures, and a total of 230 postoperative complications (3.92%). This gives an overall complication rate of 4.16%.

Conclusions This survey found that the ThermaChoice system is widely used throughout Europe. Although the methodology of this retrospective study has limitations, it has shown that the system has an excellent safety record, and notably that the complication rate appears to be lower than that observed for traditional ablation techniques as reported in the MISTLETOE study. Clinicians employing this system perceive it to be very safe and easy to use compared with traditional transcervical resection of endometrium. For the future, it is important to prospectively collect this data in order to gain the same information for the second‐generation devices, as is available for the ‘gold standard’ techniques for endometrial ablation.
Actual evapotranspiration and deficit: biologically meaningful correlates of vegetation distribution across spatial scales
Authors: Stephenson Nathan
Published: June 2003

Correlative approaches to understanding the climatic controls of vegetation distribution have exhibited at least two important weaknesses: they have been conceptually divorced across spatial scales, and their climatic parameters have not necessarily represented aspects of climate of broad physiological importance to plants. Using examples from the literature and from the Sierra Nevada of California, I argue that two water balance parameters—actual evapotranspiration (AET) and deficit (D)—are biologically meaningful, are well correlated with the distribution of vegetation types, and exhibit these qualities over several orders of magnitude of spatial scale (continental to local). I reach four additional conclusions. (1) Some pairs of climatic parameters presently in use are functionally similar to AET and D; however, AET and D may be easier to interpret biologically. (2) Several well‐known climatic parameters are biologically less meaningful or less important than AET and D, and consequently are poorer correlates of the distribution of vegetation types. Of particular interest, AET is a much better correlate of the distributions of coniferous and deciduous forests than minimum temperature. (3) The effects of evaporative demand and water availability on a site's water balance are intrinsically different. For example, the ‘dry’ experienced by plants on sunward slopes (high evaporative demand) is not comparable to the ‘dry’ experienced by plants on soils with low water‐holding capacities (low water availability), and these differences are reflected in vegetation patterns. (4) Many traditional topographic moisture scalars—those that additively combine measures related to evaporative demand and water availability—are not necessarily meaningful for describing site conditions as sensed by plants; the same holds for measured soil moisture. However, using AET and D in place of moisture scalars and measured soil moisture can solve these problems.
Effect of ceramic surface treatment on the shear bond strengths of two resin luting agents to all‐ceramic materials
Authors: Saygili G. , Şahmali S.
Published: June 2003

summary  The purpose of this study was to evaluate the bond strengths of some resin luting cements of two different all ceramic materials (In‐Ceram, IPS‐Empress). Composite cylinders 3·2 × 2 mm were prepared on the ceramic surfaces for a shear test. Four ceramic surface treatments were performed. (i) As received, (ii) grinding with diamond bur, (iii) sandblasting with 50 μm alumina grit and (iv) HF acid treatment and sandblasting with 50 μm alumina grit. Ceramic specimens were treated with one of the four methods and then cemented together with each of the two luting agents. The tested luting cements were Panavia F and Clearfil Se Bond (CSeB). The CSeB demonstrated the highest bond strength (59·95 MPa) regardless of the ceramic blocks. The average of load to fracture the In‐Ceram blocks luted with Panavia F cement was 25·89 MPa. The mean shear bond strength of IPS Empress blocks luted with Panavia F cement was 10·31 MPa. Grinding the surface with a diamond bur for In‐Ceram blocks luted with Panavia‐F was 30·93 MPa and with CSeB was 77·04 MPa. For IPS‐Empress blocks these values decreased to 12·39 MPa for Panavia‐F and 30·84 MPa for CSeB. Acid etching of the surfaces with HF acid demonstrated a weak tendency to improve bond strength (In‐Ceram→Panavia‐F= 14·59 MPa and CSeB=59·32 Mpa; IPS‐Empress→ Panavia‐F=5·85 MPa and CSeB= 23·33 MPa).
Influence of filler loading on the two‐body wear of a dental composite
Authors: Hu X. , Marquis P. M. , Shortall A. C.
Published: June 2003

summary  The purpose of the study was to explore the fundamental wear behaviour of a dental composite with different filler loadings under two‐body wear conditions. The parent resin and filler components were mixed according to different weight ratios to produce experimental composites with filler loadings ranging from 20 to 87·5% by weight. A two‐body wear test was conducted on the experimental composites using a wear‐testing machine. The machine was designed to simulate the impact of the direct cyclic masticatory loading that occurs in the occlusal contact area in vivo. The results showed that there was little increase in the rate of wear with filler loadings below 60 wt%, but a sharp increase between 80 and 87·5 wt% in filler loading. Wide striations and bulk loss of material were apparent on the wear surfaces at higher filler loadings. Coefficients of friction increased with filler loading and followed the increase in rate of wear loss closely. It was concluded that, under two‐body wear conditions, addition of high levels of filler particles into the resin matrix could reduce the wear resistance of dental composites. This finding may help when designing future dental composites for use in particular clinical settings.
The condylar asymmetry measurements in different skeletal patterns
Authors: Sağlam A. M. Şahi̇n
Published: June 2003

summary  In the present study, condylar asymmetry measurements were investigated on the lateral cephalometric head radiographs and the panoramic radiographs of 72 subjects (36 males and 36 females), aged 12–16‐years and having different skeletal patterns. The lateral cephalometric head radiographs were divided into three groups according to the ANB angle: ANB angles smaller than 1°, between 1° and 5°, and larger than 5°. In addition, each group was also divided into two subgroups according to sex. The effects on the ANB angle and sex on the condylar asymmetry measurement were investigated on the panoramic radiographs by means of variance analysis. It was observed that while condylar + ramus ratio measurement was affected by the change of ANB angle, the other measurements were not affected by it.
The effect of home‐use fluoride gels on glass–ionomer, compomer and composite resin restorations
Authors: Dionysopoulos P. , Gerasimou P. , Tolidis K.
Published: June 2003

summary  The purpose of this study was to investigate the resistance to dissolution by two home‐use fluoride gels on the surface integrity of glass–ionomer, resin modified glass–ionomer, compomer and composite resin restorations. Class V cavities prepared in extracted teeth were restored with a glass–ionomer (Fuji II), a resin modified glass–ionomer (Vitremenr), two compomers (Dyract and F‐2000) and a composite resin (Z‐100).

Groups of five specimens of each material were treated for 24 h with one of the following: (i) distilled water, (ii) neutral fluoride gel and (iii) acidulated phosphate fluoride (APF) gel.

Surface degradation of the restorations was studied using standard electron microscopy (SEM), rated according to specific criteria and statistically analysed by the Wilcoxon test (rank sums).

Acidulated phosphate fluoride was found to have a significant effect on all examined materials, while minimal effects resulted from the neutral fluoride gel compared with the control group. The effect of home‐use fluoride gels on glass–ionomer, compomer and composite resin restorations.
A new silicon‐based root canal sealer (Roekoseal®‐Automix)
Authors: Gençoglu N. , Türkmen C. , Ahiskali R.
Published: June 2003

summary  This study evaluated the new silicon‐based sealer ‘Roekoseal®‐Automix’ (RSA) with respect to sealing, bonding capabilities and biocompatibility with rat subcutaneous connective tissue. For the microleakage study, 36 single rooted teeth were instrumented and 30 of these obturated with either Grossman's sealer or RSA using lateral condensation technique (15 of each). Six teeth were not obturated and used as control group. For investigating bonding capability, 10 of the obturated roots with RSA and Grossman's sealer were ground and split longitudinally and examined by scanning electron microscopy (SEM). The RSA was found to seal significantly better than Grossman's sealer. The SEM examination revealed a good bond between RSA and the dentine and between RSA and the gutta‐percha. Tissue reaction was evaluated by injecting 0·1 mL RSA into the connective tissue of 21 male Albino–Wistar rats and observing at 24 h, 7 days and 30 days and 30 days. Formation of a new granulation tissue with fibrous tissue adjacent to the material at 30 days. This study found that RSA performed well.
Effects of two vitamins, two growth factors and dexamethasone on the proliferation of rat bone marrow stromal cells and osteoblastic MC3T3‐E1 cells
Authors: Taira M. , Nakao H. , Takahashi J. , Araki Y.
Published: June 2003

summary  The purpose of this investigation was to examine the effects of the addition of five cytokines such as vitamin C, vitamin D, bone morphogenetic protein (BMP), transforming growth factor‐β (TGF‐β) and dexamethasone (Dex) to Dulbecco's modified Eagle (DME) medium on the proliferation of Sprague–Dawley (SD) rats' bone marrow stromal cells and osteoblastic MC3T3‐E1 cells by conducting 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide (MTT) assay. For bone marrow stromal cells, vitamin C was needed for doubling the cell viability. While BMP, TGF‐β and vitamin D maintained the growth rate given by vitamin C, Dex with β‐glycerophosphate (β‐GP) slightly reduced this cell proliferation rate. For MC3T3‐E1 cells, the addition of four cytokines examined (vitamin C, vitamin D, TGF‐β and BMP) did not significantly increase the cell proliferation while Dex with vitamin C and β‐GP slightly enlarged the cell proliferation. It can be pointed out that vitamin C in DME medium is indispensable for rapid proliferation of bone marrow stromal cells that contain many osteo‐progenitor cells but is not effective for quick increase of osteoblastic MC3T3‐E1 cells. This finding appears to contribute to tissue engineering therapy to fix bone and periodontal defects in dentistry.
Effect of design of pre‐fabricated posts and post heads on the retention of various cements and core materials
Authors: Hochman N. , Feinzaig I. , Zalkind M.
Published: June 2003

summary  The retention of new Para Post (PP) rounded undercut post head (PP‐XT) was compared with the conventional flattened head (PP‐P), using amalgam Dentacore and Synergy composite as core materials. The retention of the posts PP (passive serrated), PP‐P (passive serrated with venting channels), PP‐XP (passive, raised diamond‐style pattern) and PP‐XT (threaded on the coronal portion, and passive, raised diamond‐shaped pattern on the apical portion), cemented with zinc phosphate cement (ZPC) or Duo Cement to extracted teeth, was evaluated. Tensile strength plots were recorded using an Instron instrument, while pulling the post and core in opposite directions. The following conclusions were drawn from this study: (i) The round undercut PP‐XT head was more retentive than the PP‐P head with both core materials. (ii) Amalgam was more retentive than Synergy with both head designs. (iii) PP‐XT was the most retentive post to extracted tooth canals and PP‐XP was the least retentive with either ZPC or Duo Cement. Post retention with (iv) ZPC in decreasing order of magnitude: PP‐XT > PP‐P > PP > PP‐XP; and with Duo Cement: PP‐XT > PP > PP‐P > PP‐XP ‐ ZPC exhibited the highest retention of cemented posts.
Influence of fibre position on the flexural properties and strain energy of a fibre‐reinforced composite
Authors: Ellakwa A. , Shortall A. , Marquis P.
Published: June 2003

summary  The introduction of laboratory‐processed composite systems and fibre reinforcement techniques have increased the possibilities for the prosthetic replacement of missing tooth tissues. Laboratory fabrication variables may significantly influence the properties of the final prosthesis. During the construction of a fibre‐reinforced bridge it is necessary to place the fibre at some distance from the fitting surface of the restoration in the pontic region. No guidelines are available for optimal fibre placement in this respect. The purpose of this study was to assess the influence of placing ultra high molecular weight polyethylene (UHMWPE) fibre at five different distances from the tensile side of test samples on flexural properties and the strain energy stored within the dental composite. The results of this investigation showed that whilst moving the fibre reinforcement away from the tensile side by up to 1·5 mm led to a significant reduction in flexural strength, there was no significant decline in the increase in strain energy stored within the tested composite until this distance was exceeded.
Analysis of kinesiograph recordings and masticatory efficiency after treatment of non‐reducing disk displacement of the temporomandibular joint
Authors: Sato S. , Nasu F. , Motegi K.
Published: June 2003

summary  The purpose of this study was to clarify the kinesiographs of chewing movement and masticatory efficiency before and after treatment in patients with non‐reducing disk displacement of the temporomandibular joint (TMJ). Twenty patients who were diagnosed with unilateral non‐reducing disk displacement of the TMJ were treated with pumping of the joint with injection of sodium hyaluronate. Chewing movement patterns in these patients were evaluated, using mandibular kinesiography (MKG) at their initial visit and at mean 19‐month follow‐up and the results were compared. Masticatory efficiency was also measured. As controls, 23 volunteers without TMJ dysfunction were employed. Far from the results of normal volunteers, chewing movement patterns of the patients on MKG did not show deviation to the chewing side in the TMJ‐unaffected‐side chewing in the horizontal plane. However, such patterns of the patients became similar to those of normal volunteers after treatment. Masticatory efficiency of the patients improved after treatment, though it was impaired at initial visit. The MKG and masticatory efficiency test appeared to be a useful method of comparing masticatory function before and after treatment in patients with non‐reducing disk displacement of the TMJ.
The effect of curing with plasma light on the shrinkage of dental restorative materials
Authors: Deb S. , Mallett R. , Millar B.
Published: June 2003

summary  Commercially available light activated dental composites were used in this study to compare the shrinkage following curing with plasma light (Apollo95E, DMDS) and a convention halogen dental curing light (Prismetics Lite II, Dentsply). Polymerization shrinkage was determined by measuring the strain in one dimension by means of a contacting transducer. The percentage linear shrinkage were: Spectrum H = 1·84 + 0·31, P = 1·49 + 0·35*; Ana aesthetic H = 2·04 + 0·38, P = 1·85 + 0·27; Esthet.x H = 1·66 + 0·28, P = 1·69 + 0·25; Dyract AP H = 2·39 + 0·33, P = 2·18 + 0·35*; Apollo Restore H = 1·88 + 0·36, P = 1·42 + 0·33*; Surefil H = 0·88 + 0·28, P = 0·99 + 0·30 where * = significantly different, t‐test at P < 0·05. The results suggested that there was less shrinkage when curing some, but not all, materials using the plasma light, although this could be attributed to a reduced level of polymerization.
Craniofacial morphology and obstructive sleep apnoea: a cephalometric analysis
Authors: Hoekema A. , Hovinga B. , Stegenga B. , De Bont L. G. M.
Published: June 2003

summary  The craniofacial morphology of 31 male patients diagnosed with obstructive sleep apnoea syndrome (OSAS) and 37 healthy male subjects were compared using cephalometric evaluation of lateral skull radiographs. The aim was to evaluate which cephalometric variables related to craniofacial morphology discriminate between OSAS patients and non‐OSAS subjects. Sixteen cephalometric measurements were determined to study the craniofacial morphology. Differences in cephalometric variables between the two groups were analysed with unpaired Student t‐tests (significance level 0·05). A multiple regression analysis was used to evaluate the joint predictive value of selected variables. With regard to five variables, significant differences were observed between OSAS patients and non‐OSAS subjects (P < 0·05). Data indicated a relatively anterior position of the maxilla, an increase of the mid‐facial height and a more inferiorly located hyoid bone in the OSAS patient group. The multiple regression analysis yielded a model discriminating between OSAS patients and non‐OSAS subjects, which included two hyoid bone variables and one related with the intermaxillary relationship. A causal relationship between cephalometric variables of craniofacial morphology and OSAS is not sufficiently supported by our data. Presumably, hyoid bone position is of predictive value in the cephalometric discrimination between OSAS patients and non‐OSAS subjects.
Analysis of surface roughness of glass–ionomer cements and compomer
Authors: Pedrini D. , Candido M. S. M. , Rodrigues A. L.
Published: June 2003

summary  The purpose of this study was to evaluate the surface roughness of two glass–ionomer cements (Vitremer and Chelon‐Fil), and one compomer (Dyract) when submitted to different finishing/polishing procedures at different times. A hundred 80‐sample discs were made of each material and randomly divided into six finishing/polishing groups: mylar strip (control); Sof‐Lex discs; diamond burs; diamond burs/Sof‐Lex discs; 30‐fluted carbide bur; 30‐fluted carbide bur/Sof‐Lex discs. These procedures were carried out immediately after preparation of the samples, after 24 and 168 h. Average surface roughness (Ra) was measured with a profilometer and the values were compared using anova (P < 0·05). The smoothest surface for all materials was obtained when cured in contact with the mylar strip. All other tested products increased surface roughness of restorative materials, but Sof‐lex discs lead to better results. The worst results were verified with diamond burs. The finishing/polishing procedures, when performed immediately, can improve the roughness of glass–ionomer cements but not of the compomer tested.
In vitro retention force changes of prefabricated attachments for overdentures
Authors: Besimo C. E. , Guarneri A.
Published: June 2003

summary  Changes in the retention force of six prefabricated spherical and cylindrical attachments were examined in vitro under continuous loading. The testing machine permitted insertion–separation cycles to be tested under reproducible conditions while a calibrated measuring device determined the insertion and retention forces. At the beginning, during the so‐called run‐in period, all anchoring elements showed a very unstable behaviour characterized by a varying marked increase and subsequent decrease in the retention force. During the ensuing functional period, the retention force followed a more stable course. In this phase, the frictional attachments having lamellae for activation proved more stable than did the spring‐loaded retention attachments. Furthermore, in two of five cylindrical anchors by Gerber, the spring broke. This provides support to the concept that prefabricated attachments should be constructed as robust elements composed of as few individual parts as possible. This would help to ensure that service and repairs remain at a minimum. Frictional attachments with lamellae for activation are to be preferred for use in matrices and patrices over attachments having spring‐loaded retention.
Oral health in relation to wearing removable dentures provided by dentists, denturists and laboratory technicians
Authors: Tuominen R.
Published: June 2003

summary  The aim of this study was to evaluate the oral health of elderly Finnish men wearing removable dentures supplied either by dentists, denturists or laboratory technicians. From a sample of 550 men, 362 subjects were both interviewed and clinically examined. The subjects were asked a range of questions related to their oral health and dentures. Clinical examinations were carried out by one dentist using well‐defined criteria and without knowing the information the respective subjects had given in the interview. The 242 denture wearers had a higher frequency (P < 0·001) of mucous membrane lesions (78·7%) than the 120 non‐wearers (27·5%). Differences between the denture providers were small, although subjects with dentures provided by dentists had less often most of the recorded mucous membrane lesions than other denture wearers. Coating of tongue and cheilitis angularis were the most commonly encountered lesions. High levels of yeast growth were observed more frequently (P < 0·02) among subjects who had obtained their dentures from dentists (41·3%) than from either denturists (17·1%) or laboratory technicians (18·2%). Among dentate subjects, the average number of remaining teeth was higher (P < 0·05) among those who had obtained their dentures from dentists (8·7) than among subjects wearing dentures from denturists (5·9) or laboratory technicians (6·2). Subjects wearing dentures supplied by dentists had slightly better oral health than other denture wearers. The observed differences can be at least partly explained by dentists' patients having higher number of remaining teeth and also more frequent check‐up visits.
The effect of disinfectant solutions on the hardness of acrylic resin denture teeth
Authors: Pavarina A. C. , Vergani C. E. , Machado A. L. , Giampaolo E. T. , Teraoka M. T.
Published: June 2003

summary  This investigation studied the effects of disinfectant solutions on the hardness of acrylic resin denture teeth. The occlusal surfaces of 64 resin denture teeth were ground flat with abrasives up to 400‐grit silicon carbide paper. Measurements were made after polishing and after the specimens were stored in water at 37 °C for 48 h. The specimens were then divided into four groups and immersed in chemical disinfectants (4% chlorhexidine; 1% sodium hypochlorite and sodium perborate) for 10 min. The disinfection methods were performed twice to simulate clinical conditions and hardness measurements were made. Specimens tested as controls were immersed in water during the same disinfection time. Eight specimens were produced for each group. After desinfection procedures, testing of hardness was also performed after the samples were stored at 37 °C for 7, 30, 60, 90 and 120 days. Data were analysed using two‐way analysis of variance (anova) and Tukey's test at 95% confidence level. According to the results, no significant differences were found between materials and immersion solutions (P > 0·05). However, a continuous decrease in hardness was noticed after ageing (P < 0·05). It was conclude that the surfaces of both acrylic resin denture teeth softened upon immersion in water regardless the disinfecting solution.
Masticatory performance: a protocol for standardized production of an artificial test food
Authors: Albert T. E. , Buschang P. H. , Throckmorton G. S.
Published: June 2003

summary  A protocol for standardizing the production of an artificial test food was established and its reliability was determined. An artificial test food was selected based on its superior properties compared with natural foods. The primary emphasis during production was the incorporation of all 3 cm of paste‐hardener and thoroughly kneading the material for 30 s. The curing process was studied to determine overall setting time. After at least 30 min, the physical properties of the test food were ready to be measured. The overall mean hardness of the test food was 489 ± 60 load grams. Random error between operators was ±16 load grams while batches differed by ±13 load grams and individual tablets differed by ±15 load grams. This protocol provides a reliable standardized method for future masticatory performance studies.
Characterization of RAT, an autolysis regulator in Staphylococcus aureus
Authors: Ingavale S. S. , Van Wamel W. , Cheung A. L.
Published: June 2003

In trying to identify genetic loci involved in the regulation of cap5 genes in Staphylococcus aureus, we isolated a transposon mutant that exhibited a growth defect, enhanced autolysis and increased sensitivity to Triton X‐100 and penicillin, attributable in part to increased murein hydrolase activity. Analysis of the chromosomal sequence flanking the transposon insertion site revealed that the gene disrupted in the mutant encodes an open reading frame of 147 amino acids. We named this gene rat, which stands for regulator of autolytic activity. Sequence analysis indicated that Rat is homologous to the MarR and, to a lesser extent, the SarA protein families. Mutations in rat resulted in decreased expression of known autolytic regulators lytSR, lrgAB and arlRS. Gel shift studies indicated that Rat binds to the lytRS and arlRS promoters, thus confirming Rat as a DNA‐binding protein to these known repressors of autolytic activity. As anticipated, rat appears to be a negative regulator of autolysin genes including lytM and lytN. These data suggest that the rat gene product is an important regulator of autolytic activity in S. aureus.
Haemophore‐mediated signal transduction across the bacterial cell envelope in Serratia marcescens: the inducer and the transported substrate are different molecules
Authors: Rossi Maria‐Silvia , Paquelin Annick , Ghigo Jean Marc , Wandersman Cécile
Published: June 2003

Numerous bacteria are able to use free and haemoprotein‐bound haem as iron sources because of the action of small secreted proteins called haemophores. Haemophores have very high affinity for haem, and can therefore extract haem from the haem‐carrier proteins and deliver it to the cells by means of specific cell surface receptors. Haem is then taken up and the empty haemophores are recycled. Here, we report a study of the regulation of the Serratia marcescens has operon which is involved in haemophore‐dependent haem acquisition. We characterized two genes encoding proteins homologous to specific ECF sigma and antisigma factors. We showed that they regulate the synthesis of the haemophore‐specific outer membrane receptor, HasR, by a signal transduction mechanism similar to the siderophore surface‐signalling systems. We also showed the essential role of HasR itself in this process. Using haem‐loaded and haem‐free haemophore, we identified the stimulus for the HasR‐mediated signal transduction as being the binding of the haem‐loaded haemophore to HasR. Thus, unlike siderophore‐uptake systems, in which the signalling molecule is the transported substrate itself, in the haemophore‐dependent haem uptake system the inducer and the transported substrate are different compounds.
Membrane‐specific targeting of green fluorescent protein by the Tat pathway in the cyanobacterium Synechocystis PCC6803
Authors: Spence Edward , Sarcina Mary , Ray Nicola , Møller Simon Geir , Mullineaux Conrad W. , Robinson Colin
Published: June 2003

The transport and sorting of extracytoplasmic proteins in cyanobacteria is made complex by the presence of a highly differentiated membrane system. Proteins destined for the periplasm and thylakoid lumen are initially transported by Sec‐ and Tat‐type pathways but little is known of the mechanisms that ultimately direct them to the correct destinations. We have generated a Synechocystis PCC6803 transformant that expresses a fusion protein comprising the Tat‐specific targeting signal of Escherichia coli TorA linked to green fluorescent protein (GFP). Immunoblotting indicates the presence of mature‐size GFP but no precursor form, demonstrating that efficient translocation has taken place. Confocal microscopy and immunogold electron microscopy reveal GFP to be almost exclusively located in the periplasm, with almost no protein evident in the thylakoid network. These data point to the operation of highly effective sorting pathways for soluble proteins in this cyanobacterium. The observed sorting of the GFP suggests that either (a) the Tat apparatus is located only in the plasma membrane or (b) the TorA‐GFP is targeted across either membrane but the GFP is subsequently directed to the periplasm, perhaps by a default sorting pathway to this compartment.
The kinetic properties of the carboxy terminal domain of the Bacillus licheniformis 749/I BlaR penicillin‐receptor shed a new light on the derepression of β‐lactamase synthesis
Authors: Duval Valérie , Swinnen Marc , Lepage Sophie , Brans Alain , Granier Benoît , Franssen Christine , Frère Jean‐Marie , Joris Bernard
Published: June 2003

To study the properties of the BlaR penicillin‐receptor involved in the induction of the Bacillus licheniformisβ‐lactamase, the water‐soluble carboxy terminal domain of the protein (BlaR‐CTD) was overproduced in the periplasm of Escherichia coli JM105 and purified to protein homogeneity. Its interactions with various β‐lactam antibiotics were studied. The second‐order acylation rate constants k2/K′ ranged from 0.0017 to more than 1 µM−1s−1 and the deacylation rate constants were lower than 4 × 10−5 s−1. These values imply a rapid to very rapid formation of a stable acylated adduct. BlaR‐CTD is thus one of the most sensitive penicillin‐binding proteins presently described. In the light of these results, the kinetics of β‐lactamase induction in Bacillus licheniformis were re‐examined. When starting with a rather high cell density, a good β‐lactamase substrate such as benzylpenicillin is too sensitive to β‐lactamase‐mediated hydrolysis to allow full induction. By contrast, a poor β‐lactamase substrate (7‐aminocephalosporanic acid) can fully derepress β‐lactamase expression under conditions where interference of the antibiotic with cell growth is observed. These results suggest that acylation of the penicillin receptor is a necessary, but not sufficient, condition for full induction.