bluuebunny/crossref_metadata_2025 huggingface dataset:
An Evaluation of Internet Sites for Burn Scar Management
Authors: Bohacek L. , Gomez M. , Fish J. S.
Published: September 2004

Patients rely on the Internet for medical information. It is difficult to discern which resources are accurate or appropriate for patients. The purpose of this study was to develop a quality-assessment tool for health Internet Web sites and to apply this tool to assess the quality of burn scar management information on the Internet. Between September and December 2001, we prospectively evaluated all Web sites on the Internet search engine Yahoo!® containing the headings “burn scar management,” “burn scar healing,” “burn scar treatment,” and “burn scar therapy.” The quality of each Web site's medical information was evaluated using our scoring system consisting of the following two components: quality and technical characteristics. The total score for each Web site was converted to a percent grade (eg, ≥80% = excellent, 70 to 79% = very good, 60 to 69% = good, 50 to 59% = fair, and <50% = poor). The Web sites were grouped into three categories: commercial (for profit), academic (university, hospital), and organizational (nonprofit). Of 88 Web sites evaluated, the majority 68 (77%) were commercial, 7 (8%) academic, and 13 (15%) organizational. Burn scar management information on the Internet was poor in the majority (79%) of commercial Web sites and was excellent, very good, or good in the majority of academic (86%) and organizational (77%) Web sites. Using our health information evaluation, we found that the majority of burn scar management information on the internet (77%) was of fair or poor quality. Academic and organizational Web sites had the best quality of burn scar management information. Additional testing of the developed tool will be needed to analyze the reproducibility of the results and their applicability in other medical domains.
Chronic Nightmares After Severe Burns: Risk Factors and Implications for Treatment
Authors: Low J. F. Aili , Dyster-Aas Johan , Willebrand Mimmie , Kildal Morten , Gerdin Bengt , Ekselius Lisa
Published: September 2004

Although patients frequently experience sleep disturbances and nightmares in the first weeks after a severe burn, information is scarce on the course and prevention of this problem. Prolonged experience of nightmares in adults is one of the symptoms of posttraumatic stress disorder. The aim of this work was to determine risk factors for developing chronic nightmares after severe burns. Personality traits and coping strategies were assessed. As part of a follow-up study of patients treated at the Burn Center at Uppsala University Hospital, Uppsala, Sweden, between 1980 and 1995, the questionnaires of 166 patients (34 females, 132 males, average age 50 years, average burn size 25% TBSA, full-thickness burn size 10% TBSA, average time since burn 11.4 years) were analyzed. The effects of individual personality traits and coping strategies on the frequency of nightmares were evaluated by regression analysis. Nightmares were reported by 43% of the patients, by females more frequently than males. The frequency of nightmares was shown to be associated with the size of the full-thickness burn. The use of Avoidance or Revaluation/Adjustment scales as coping strategies and the presence of Somatic Trait Anxiety as a personality trait were associated with a higher frequency of nightmares after correction for gender. In contrast, persons seeking Emotional Support as a coping strategy reported significantly fewer nightmares. Certain personality traits and coping strategies apparently increase the risk of having nightmares after a severe burn. Helping persons at risk develop different coping strategies may be a possible means of prevention or treatment.
Researchers BEWARE! Attrition and Nonparticipation at Large
Authors: McQuaid Deborah , Barton Joanne , Campbell Elizabeth
Published: September 2004

There are many obstacles in undertaking psychological burns research with children and adolescents, and the more useful longitudinal studies are particularly fraught with difficulty. This work introduces and discusses the problems of attrition and nonparticipation encountered in our attempt to use a rigorous design and methodology to study this population. The aim is to provide the impetus for a more thorough, detailed review of this problem.
Hydrofluoric Acid Burn Resulting From Ignition Of Gas From A Compressed Air Duster
Authors: Foster Kevin N. , Jones LouAnn , Caruso Daniel M.
Published: September 2004

A young female suffered burns to her hand after the ignition of gas from a compressed air duster. After debridement and dressing, the patient continued to have pain out of proportion to injury that was refractory to intravenous morphine. The material safety data sheet revealed that the chemical used was 1,1-difluoroethane. High temperatures can cause decompensation to form hydrofluoric acid. Calcium gluconate gel was applied topically to the patient's burns, which caused prompt and complete relief of her pain. A review of different compressed air duster products revealed that the main ingredient in each was a halogenated hydrocarbon. Although not considered flammable, all products have warnings regarding the possibility of ignition under various circumstances. Ignition of the gas in compressed air cleaners not only can cause flame burns, it can also cause chemical damage from exposure to hydrogen and fluoride ions. Prompt recognition and treatment is necessary to prevent severe injury.
A Study of Clinical and Laboratory Features of 14 Indian Patients With Dysferlinopathy
Authors: Khadilkar S V , Singh R K , Kulkarni K S , Chitale A R
Published: September 2004

Aim

The aim of the study was to analyze the clinical and laboratory characteristics of Indian patients having dysferlinopathy.

Methods and Material

Patients with limb girdle muscular dystrophy (LGMD) were prospectively studied. History, examination, and laboratory evaluation, including creatine kinase, electrophysiology, and muscle biopsy with immunocytochemistry, was carried out.

Results and Conclusions

Fourteen patients (14.58% of patients with LGMD) had dysferlin deficiency. The mean age at onset was 19.9 years. Nine patients had distal presentation and in the remaining 5 patients, it was proximal. Asymmetry of muscle weakness was seen in 6 patients. Three patients experienced initial calf pains with transient hypertrophy. Gastrocnemius and tibialis anterior muscles were almost similarly affected. The brunt of proximal weakness was on iliopsoas, hip adductors, hamstrings, and quadriceps muscles. Upper limbs were mildly affected. Biceps lump was seen in 4 patients. The phenotype was mild and ambulation was maintained in all patients, many years into the illness.
Evidence for a Direct Link between Glutathione Biosynthesis and Stress Defense Gene Expression in Arabidopsis[W]
Authors: Ball Louise , Accotto Gian-Paolo , Bechtold Ulrike , Creissen Gary , Funck Dietmar , Jimenez Ana , Kular Baldeep , Leyland Nicola , Mejia-Carranza Jaime , Reynolds Helen , Karpinski Stanislaw , Mullineaux Philip M.
Published: September 2004

The mutant regulator of APX2 1-1 (rax1-1) was identified in Arabidopsis thaliana that constitutively expressed normally photooxidative stress-inducible ASCORBATE PEROXIDASE2 (APX2) and had ≥50% lowered foliar glutathione levels. Mapping revealed that rax1-1 is an allele of γ-GLUTAMYLCYSTEINE SYNTHETASE 1 (GSH1), which encodes chloroplastic γ-glutamylcysteine synthetase, the controlling step of glutathione biosynthesis. By comparison of rax1-1 with the GSH1 mutant cadmium hypersensitive 2, the expression of 32 stress-responsive genes was shown to be responsive to changed glutathione metabolism. Under photo-oxidative stress conditions, the expression of a wider set of defense-related genes was altered in the mutants. In wild-type plants, glutathione metabolism may play a key role in determining the degree of expression of defense genes controlled by several signaling pathways both before and during stress. This control may reflect the physiological state of the plant at the time of the onset of an environmental challenge and suggests that changes in glutathione metabolism may be one means of integrating the function of several signaling pathways.
A High-Resolution Transcript Profile across the Wood-Forming Meristem of Poplar Identifies Potential Regulators of Cambial Stem Cell Identity[W]
Authors: Schrader Jarmo , Nilsson Jeanette , Mellerowicz Ewa , Berglund Anders , Nilsson Peter , Hertzberg Magnus , Sandberg Göran
Published: September 2004

Plant growth is the result of cell proliferation in meristems, which requires a careful balance between the formation of new tissue and the maintenance of a set of undifferentiated stem cells. Recent studies have provided important information on several genetic networks responsible for stem cell maintenance and regulation of cell differentiation in the apical meristems of shoots and roots. Nothing, however, is known about the regulatory networks in secondary meristems like the vascular cambium of trees. We have made use of the large size and highly regular layered organization of the cambial meristem to create a high-resolution transcriptional map covering 220 μm of the cambial region of aspen (Populus tremula). Clusters of differentially expressed genes revealed substantial differences in the transcriptomes of the six anatomically homogenous cell layers in the meristem zone. Based on transcriptional and anatomical data, we present a model for the position of the stem cells and the proliferating mother cells in the cambial zone. We also provide sets of marker genes for different stages of xylem and phloem differentiation and identify potential regulators of cambial meristem activity. Interestingly, analysis of known regulators of apical meristem development indicates substantial similarity in regulatory networks between primary and secondary meristems.
Control of Plant Trichome Development by a Cotton Fiber MYB Gene[W]
Authors: Wang Shui , Wang Jia-Wei , Yu Nan , Li Chun-Hong , Luo Bin , Gou Jin-Ying , Wang Ling-Jian , Chen Xiao-Ya
Published: September 2004

Cotton (Gossypium spp) plants produce seed trichomes (cotton fibers) that are an important commodity worldwide; however, genes controlling cotton fiber development have not been characterized. In Arabidopsis thaliana the MYB gene GLABRA1 (GL1) is a central regulator of trichome development. Here, we show that promoter of a cotton fiber gene, RD22-like1 (RDL1), contains a homeodomain binding L1 box and a MYB binding motif that confer trichome-specific expression in Arabidopsis. A cotton MYB protein GaMYB2/Fiber Factor 1 transactivated the RDL1 promoter both in yeast and in planta. Real-time PCR and in situ analysis showed that GaMYB2 is predominantly expressed early in developing cotton fibers. After transferring into Arabidopsis, GL1::GaMYB2 rescued trichome formation of a gl1 mutant, and interestingly, 35S::GaMYB2 induced seed-trichome production. We further demonstrate that the first intron of both GL1 and GaMYB2 plays a role in patterning trichomes: it acts as an enhancer in trichome and a repressor in nontrichome cells, generating a trichome-specific pattern of MYB gene expression. Disruption of a MYB motif conserved in intron 1 of GL1, WEREWOLF, and GaMYB2 genes affected trichome production. These results suggest that cotton and Arabidopsis use similar transcription factors for regulating trichomes and that GaMYB2 may be a key regulator of cotton fiber development.
Borreliae in Ixodes ricinus ticks feeding on humans
Authors: Hubálek Z. , Halouzka J. , Juřicová Z.
Published: September 2004

Abstract.  A total of 298 Ixodes ricinus (L.) ticks (Acari: Ixodidae) feeding on humans in the Czech Republic were tested for borreliae (Borrelia burgdorferi sensu lato) by darkfield microscopy between 1997 and 2003. A majority (68%) of the supplied I. ricinus ticks were nymphs, 25% were females and 7% were larvae. Overall, 20% of 74 examined females and 9% of 203 examined nymphs (but none of 21 examined larvae) were infected with borreliae. The proportion of ticks with a high infection load (>100 spirochetes) was 4% in females and 2% in nymphal I. ricinus. During the year, the highest numbers and proportions of infected nymphal and female ticks were taken from humans in June. Detection of borreliae in the ticks feeding on humans might be helpful in the prophylaxis of Lyme borreliosis.
Sampling fleas: the reliability of host infestation data
Authors: Krasnov B. R. , Khokhlova I. S. , Shenbrot G. I.
Published: September 2004

Abstract. The use of measures of host infestation as a reliable indicator of a flea population size to be used in interspecific comparisons was considered. The abundance of fleas collected from host bodies and collected from host burrows was compared among 55 flea species, controlling for the effect of flea phylogeny. The mean number of fleas on host bodies correlated positively with the mean number of fleas in host burrows/nests both when the entire data pool was analysed and for separate subsets of data on ‘fur’ fleas and ‘nest’ fleas. This was also true for a within‐host (Microtus californicus) between‐flea comparison. The results of this study demonstrate that, in general, the index of host body infestation by fleas can be used reliably as an indicator of the entire population size.
A new cytotype of Simulium squamosum from south‐west Cameroon
Authors: Mustapha M. , Post R. J. , Enyong P. , Lines J.
Published: September 2004

Abstract.  A new cytotype of Simulium squamosum Enderlein (Diptera: Simuliidae) (here named S. squamosum‘D’) is described from around Mount Cameroon in south‐west Cameroon on the basis of sex‐chromosome differences on the short arm of chromosome I. Two polymorphic inversions, IS‐To (a new inversion) and IS‐2, are partially Y linked. These inversions usually occur together, although IS‐To has a higher frequency and is more strongly Y linked than IS‐2. This sex‐chromosome system has not been previously described and the occurrence and evolution of sex‐chromosome systems in S. squamosum is discussed.
Habitat characteristics of Anopheles gambiae s.s. larvae in a Kenyan highland
Authors: Minakawa N. , Sonye G. , Mogi M. , Yan G.
Published: September 2004

Abstract.  Anopheline larval habitats associated with a swamp, were examined in a highland area (1910 m elevation) of western Kenya. A significant association was found between occurrence of Anopheles gambiae Giles s.s. (Diptera: Culicidae) larvae and two factors, habitat size and vegetation type. Over 80% of An. gambiae s.s. larvae were found in small isolated pools, characterized by short plants, occurring in both swamp margins and roadside ditches. However, Anopheles gambiae s.s. was not found in habitats marked by papyrus and floating plants. The larval habitat of An. gambiae s.s. was characterized by warmer daytime temperatures of water, which were significantly affected by habitat size and plant size. The density of indoor resting An. gambiae s.s. was 0.22 per house and negatively associated with distance from the swamp. These results indicate that the practice of swamp cultivation, in populated areas of the African highlands, increases availability and enhances habitat conditions for the malaria vector.
Biological diversity versus risk for mosquito nuisance and disease transmission in constructed wetlands in southern Sweden
Authors: Schäfer M. L. , Lundström J. O. , Pfeffer M. , Lundkvist E. , Landin J.
Published: September 2004

Abstract.  In southern Sweden, many wetlands have been constructed, and maintaining or increasing biological diversity is often included in the aims. Some wetlands are constructed near human settlements, thus raising the problem of wetlands being associated with mosquitoes (Diptera: Culicidae). Increased biodiversity (including mosquito diversity) is considered desirable, whereas mosquito nuisance from a human point of view is not. Adult mosquito abundance, diversity and species assemblages of constructed wetlands were compared to natural wetlands. The potential of constructed wetlands for mosquito nuisance and transmission of mosquito‐borne viruses was evaluated. The study areas included five constructed and four natural wetlands. Mosquito abundance and species richness were higher in the natural than in the constructed wetlands, and showed a positive correlation with wetland size. Mosquito species assemblages formed three clusters, which were not explained by origin, size and water permanence of wetlands. In a redundancy analysis, however, mosquito faunas showed significant relationships with these variables, and size and origin of wetlands were most important. Major nuisance species (multivoltine species feeding on mammals and laying eggs on soil) were found in all wetlands, although in relatively low numbers. Risk assessment for Sindbis virus transmission showed moderate risk for two constructed wetlands near human settlements. It is concluded that small size of constructed wetlands has the advantage of low mosquito numbers from a human point of view. The use of functional groups is recommended as a tool for presenting mosquito data to the public, and for helping communication between scientists and administrative decision makers.
Records of Chrysomya albiceps in the Ukraine
Authors: Verves YU. G.
Published: September 2004

Abstract.  First records of the presence of the blowfly, Chrysomya albiceps in the western and northern Ukraine are presented.
Changes in HIV/AIDS/STI Knowledge, Attitudes and Practices among Commercial Sex Workers and Military Forces in Port Loko, Sierra Leone
Authors: Larsen Mandi M. , Casey Sara E. , Sartie Moï‐Tenga , Tommy Judith , Musa Tamba , Saldinger Martha
Published: September 2004

Sierra Leone suffered from 11 years of civil war (1991–2002) resulting in tens of thousands of deaths and mutilations together with massive population displacement. In 2001, ARC International, Sierra Leone conducted a baseline survey of 201 commercial sex workers (CSWs) and 202 military respondents on the knowledge, attitudes and practices surrounding HIV/AIDS and STIs in Port Loko, Sierra Leone. In 2003, a comparable post‐intervention survey of 202 CSWs and 205 military respondents was performed. Comparison of baseline and post‐intervention results showed that HIV/AIDS knowledge increased among both groups, with those able to name three effective means of avoiding AIDS increasing from 5 per cent to 70 per cent among CSWs, and 11 to 75 per cent among the military. Reported condom use during last sex increased among CSWs from 38 to 68 per cent and among military from 39 to 68 per cent. These results demonstrate that, despite the challenges inherent in a post‐conflict country, good‐quality AIDS‐prevention programmes can be effective.
Using Evidence to Improve Reproductive Health Quality along the Thailand‐Burma Border
Authors: Sullivan Tara M. , Maung Cynthia , Sophia Naw
Published: September 2004

The Mae Tao Clinic, located on the Thailand‐Burma border, has provided health services for illegal migrant workers in Thailand and internally displaced people from Burma since 1989. In 2001, the clinic launched a project with the primary aim of improving reproductive health services and the secondary aim of building clinic capacity in monitoring and evaluation (M&E). This paper first presents the project's methods and key results. The team used observation of antenatal care and family‐planning sessions and client exit interviews at baseline and follow‐up, approximately 13 months apart, to assess performance on six elements of quality of care. Findings indicated that improving programme readiness contributed to some improvement in the quality of services, though inconsistencies in findings across the methods require further research. The paper then identifies lessons learned from introducing M&E in a resource‐constrained setting. One key lesson was that a participatory approach to M&E increased people's feelings of ownership of the project and motivated staff to collect and use data for programme decision‐making to improve quality.
Reproductive Health in Afghanistan: Results of a Knowledge, Attitudes and Practices Survey among Afghan Women in Kabul
Authors: Van Egmond Kathia , Bosmans Marleen , Naeem Ahmad Jan , Claeys Patricia , Verstraelen Hans , Temmerman Marleen
Published: September 2004

A reproductive‐health knowledge, attitudes and practices (KAP) survey was carried out among 468 Afghan women of reproductive age. A convenience sample of women was selected from attendees in the outpatient departments of four health facilities in Kabul. Seventy‐nine per cent of respondents had attended at least one antenatal consultation during their last pregnancy. Two‐thirds (67 per cent) delivered their first child between 13 and 19 years. The Caesarean‐section rate was low (1.6 per cent). Two‐thirds (67 per cent) of deliveries occurred in the home. The contraceptive prevalence rate was 23 per cent (16 per cent modern and 7 per cent natural methods). Twenty‐four per cent had knowledge of any STIs, although most of these women did not know correctly how to prevent them. Most of the women (93 per cent) needed authorization from their husband or a male relative before seeking professional health‐care.

In multivariate analysis, women's schooling was significantly associated with antenatal‐care attendance (AOR 4.78), institutional delivery (AOR 2.29), skilled attendance at birth (AOR 2.07) and use of family planning (AOR 4.59).

Reproductive‐health indicators were noted to be poor even among these women living in Kabul, a group often considered to be the most privileged. To meet the reproductive‐health needs of Afghan women, the socio‐cultural aspects of their situation — especially their decision‐making abilities — will need to be addressed.

A long‐standing commitment from agencies and donors is required, in which the education of women should be placed as a cornerstone of the reconstruction process of Afghanistan.
HIV/AIDS among Conflict‐affected and Displaced Populations: Dispelling Myths and Taking Action
Authors: Spiegel Paul B.
Published: September 2004

Conflict, displacement, food insecurity and poverty make affected populations more vulnerable to HIV transmission. However, the common assumption that this vulnerability necessarily translates into more HIV infections and consequently fuels the HIV/AIDS epidemic is not supported by data. Whether or not conflict and displacement affect HIV transmission depends upon numerous competing and interacting factors. This paper explores and explains the epidemiology of HIV/AIDS in conflict and addresses the unique characteristics that must be addressed when planning and implementing HIV/AIDS interventions among populations affected by conflict as compared with those in resource‐poor settings. These include targeting at‐risk groups, protection, programming strategies, coordination and integration and monitoring and evaluation. Areas for future HIV/AIDS operational research in conflict are discussed.
Effect of obturation technique on sealer cement thickness and dentinal tubule penetration
Authors: Weis M. V. , Parashos P. , Messer H. H.
Published: September 2004

Aim  To compare the average sealer cement film thickness and the extent and pattern of sealer penetration into dentinal tubules in association with four obturation techniques in curved root canals.

Methodology  Mesial canals of 44 extracted mandibular molars were randomly divided among the SimpliFill, continuous wave, Thermafil and 0.04 matched taper (master cones) lateral compaction obturation groups (22 canals per group). AH26 sealer cement was coloured blue‐black using Sudan Black B dye. Roots were sectioned 1, 3 and 5 mm from the working length. Specimens were photographed under 25× magnification, mounted as 35 mm slides and projected. Average sealer cement thickness (measured at 10 points around the canal wall), depth of dentinal tubule penetration and frequency of voids were determined at the 1, 3 and 5 mm levels. Data were analysed statistically for effect of obturation technique and level of section on sealer thickness and on the depth and distribution of tubule penetration.

Results  Thermafil demonstrated superior GP adaptation at all levels with a mean overall sealer cement thickness of 2.2 μm, followed by lateral compaction (11.1 μm), continuous wave (12.2 μm) and SimpliFill (47.6 μm). SimpliFill also demonstrated the highest frequency of voids (P < 0.05). Sealer cement penetrated dentinal tubules as far as the outer one‐third of dentine, with greater penetration observed buccally or lingually (P < 0.001). Penetration was not significantly affected by obturation technique, but on average was deeper and more frequent at the 3 and 5 mm levels than at the 1 mm level (P < 0.001).

Conclusions  Sealer thickness was strongly dependent on obturation technique. Assuming that minimal sealer thickness and fewer voids are good measures of long‐term sealing ability, Thermafil resulted in the best outcome. Consistent, extensive sealer penetration into dentinal tubules was seen and was unrelated to the obturation technique.
The effectiveness of syringe irrigation and ultrasonics to remove debris from simulated irregularities within prepared root canal walls
Authors: Lee S.‐J. , Wu M.‐K. , Wesselink P. R.
Published: September 2004

Aim  To compare the ability of syringe irrigation and ultrasonic irrigation to remove artificially placed dentine debris from simulated canal irregularities within prepared root canals.

Methodology  After canal enlargement, twelve canines were split longitudinally into two halves. On the wall of one half of each root canal a standard groove of 4 mm in length, 0.2 mm in width and 0.5 mm in depth was cut, 2–6 mm from the apex, to simulate uninstrumented canal extensions. On the wall of the other half, three standard saucer‐shaped depressions of 0.3 mm in diameter and 0.5 mm in depth were cut at 2, 4 and 6 mm from the apex to simulate uninstrumented canal irregularities. Each groove and depression were filled with dentine debris mixed with 2% NaOCl to simulate a situation when dentine debris accumulates in uninstrumented canal extensions and irregularities during canal preparation. Each tooth was re‐assembled by reconnecting the two halves, using wire and an impression putty material. Two per cent NaOCl was then delivered into each canal either using syringe irrigation (n = 8) or using ultrasonic irrigation (n = 8). Before and after irrigation, images of the two halves of the canal wall were taken, using a microscope and a digital camera, after which they were scanned into a PC as TIFF images. The amount of remaining dentine debris in the grooves and depressions was evaluated by using a scoring system between 0–3: the higher the score, the more the debris. The data were analysed by means of the Mann–Whitney U‐test.

Results  Both forms of irrigation reduced the debris score significantly. The debris score was statistically significantly lower after ultrasonic irrigation than after syringe irrigation (P = 0.002 for grooves, P = 0.047 for depressions).

Conclusion  Ultrasonic irrigation ex vivo is more effective than syringe irrigation in removing artificially created dentine debris placed in simulated uninstrumented extensions and irregularities in straight, wide root canals.
Root canal obturation by ultrasonic condensation of gutta‐percha. Part II: an in vitro investigation of the quality of obturation
Authors: Bailey G. C. , Ng Y. ‐L. , Cunnington S. A. , Barber P. , Gulabivala K. , Setchell D. J.
Published: September 2004

Aim  To compare the quality of root canal obturation using ultrasonic or cold condensation of gutta‐percha and to determine the effect of power setting and activation time on the quality of obturation using the former technique.

Methodology  An extracted human maxillary canine was used in an in vitro split tooth model to allow repeated obturation of the same root canal system using an ultrasonic device to thermocompact gutta‐percha without sealer. After each obturation, the root filling was removed from the tooth to allow evaluation of its quality and for the tooth to be re‐obturated. The influence of combinations (n = 10 per combination) of power setting (1, 3, 5) and activation times (4, 10, 15 s) was tested on the quality of root filling, assessed by measuring the voids within the body of the root filling as well as at the surface. Image analysis was used to quantify the voids within the body of the root filling. Cold lateral condensation of gutta‐percha served as a control.

Results  Both surface and cross‐sectional analyses revealed that different power setting and activation time combinations produced significantly fewer voids than cold lateral condensation (P < 0.05) at the apical, mid‐root and coronal levels.

Conclusions  Taking surface and cross‐sectional analysis together only power setting 5 and activation times of 10 and 15 s consistently produced ultrasonically thermocompacted root canal fillings with fewer voids than cold lateral condensation without sealer.
Biocompatibility of two commercial forms of mineral trioxide aggregate
Authors: Camilleri J. , Montesin F. E. , Papaioannou S. , McDonald F. , Pitt Ford T. R.
Published: September 2004

Aim  To examine the biocompatibility of two commercial forms of mineral trioxide aggregate (MTA), by evaluating the morphology of an established cell line.

Methodology  The two cements were cast on glass cover slips and cured for 1 or 28 days. Saos‐2 osteosarcoma cells were trypsinized and seeded at a density of 1 × 105 cells and were then placed in medium over the material‐coated coverslips for 1, 5 and 7 days. After these time intervals the media were discarded and the cells fixed. Cell morphological investigation was performed by scanning electron microscopy at various magnifications ranging from × 250 to× 500. The biocompatibility of cement constituents, alusilicate flux and bismuth oxide was also investigated.

Results  All cement samples cured for 1 day showed a confluent cell monolayer after 5 and 7 days. The response to both materials was similar. Materials cured for 28 days showed incomplete cell confluence after 1 and 5 days. Alusilicate flux and bismuth oxide did not demonstrate biocompatibility.

Conclusions  The 1‐day cured samples of two commercial forms of MTA showed good biocompatibility. However, the 28‐day cured samples were less biocompatible after 1 and 5 days.
Central adenoid cystic carcinoma of the mandible manifesting as an endodontic lesion
Authors: Chen Y. K. , Chen C. H. , Lin C. C. , Hsue S. S. , Lin Y. R. , Lin L. M.
Published: September 2004

Aim  To present a case of adenoid cystic carcinoma (ACC) in the mandible, and manifesting as a periapical lesion.

Summary  A 56‐year‐old male suffered from pain around the right mandibular first molar for approximately 1 week. Oral examination revealed that the involved tooth was restored by a full coverage crown with no obvious abnormalities. A periapical radiograph revealed two ill‐defined radiolucencies associated with the tooth, one over the mesial and another over the distal roots of the tooth; incomplete root filling and furcation involvement also being noted. The affected tooth was extracted based on the clinical impression of apical periodontitis. The surrounding tissue of the root apex was curetted and sent for histopathological examination, which revealed ACC.

Key learning points

Adenoid cystic carcinoma affecting the mandible may mimic a periapical lesion. Proper diagnosis of such a lesion is dependent on thorough clinical, radiographic and microscopic examinations.

Such a case highlights the benefits of biopsy and histological examination of collected tissues.

Diagnosis of lesions in the mandible should include salivary gland tumours.
Susceptibility to localized corrosion of stainless steel and NiTi endodontic instruments in irrigating solutions
Authors: Darabara M. , Bourithis L. , Zinelis S. , Papadimitriou G. D.
Published: September 2004

Aim  To evaluate the pitting and crevice corrosion characteristics of stainless steel (SS) and NiTi endodontic files in R‐EDTA and NaOCl irrigating solutions.

Methodology  The corrosion behaviour of two H‐files produced from different SS alloys (Mani, AISI 303 SS, Dentsply Maillefer, AISI 304 SS) and one file produced from NiTi alloy (Maillefer) was determined in R‐EDTA and NaOCl irrigating solutions by the cyclic potentiodynamic polarization method. The cutting flutes of 12 files of each material were embedded in an epoxy resin, polished, exposed to the irrigating solutions and used as an electrode. An Ag/AgCl electrode was used as a reference, a platinum plate was used as a counter electrode and polarization curves were obtained for all files in R‐EDTA and NaOCl irrigating solutions in 37 °C with a potential scan rate of 5 mV min−1. Corrosion potential (Ecorr), Corrosion current density (Icorr) and Pitting potential (Epit) were calculated from each curve. The results were statistically analysed with two‐way anova and Student‐Newman‐Keuls (SNK) multiple comparison test with materials and irrigating solutions serving as discriminating variables (a = 0.05).

Results  Cyclic polarization curves presented negative hysteresis implying that pitting or crevice corrosion are not likely to occur for all the materials examined in both irrigating solutions. In NaOCl all materials showed significantly higher Ecorr (P = 0.011) as well as lower Icorr compared with R‐EDTA reagent. Moreover, all materials demonstrated equal Epit in NaOCl, which was to be found significantly lower (P = 0.009) than the value of Epit in R‐EDTA.

Conclusions  None of the tested materials is susceptible to pitting or crevice corrosion in R‐EDTA and NaOCl solutions and from this standpoint are appropriate for the production of endodontic files.
Independent genetic mechanisms mediate turgor generation and penetration peg formation during plant infection in the rice blast fungus
Authors: Park Gyungsoon , Bruno Kenneth S. , Staiger Christopher J. , Talbot Nicholas J. , Xu Jin‐Rong
Published: September 2004

The first barrier to infection encountered by foliar pathogens is the host cuticle. To traverse this obstacle, many fungi produce specialized infection cells called appressoria. MST12 is essential for appressorium‐mediated penetration and infectious growth by the rice pathogen Magnaporthe grisea. In this study, we have characterized in detail the penetration defects of an mst12 deletion mutant. Appressoria formed by the mst12 mutant developed normal turgor pressure and ultrastructure but failed to form penetration pegs either on cellophane membranes or on plant epidermal cells. Deletion and site‐directed mutagenesis analyses indicated that both the homeodomain and zinc finger domains, but not the middle region, of MST12 are essential for appressorial penetration and plant infection. The mst12 mutant appeared to be defective in microtubule reorganization associated with penetration peg formation. In mature appressoria, the mutant lacked vertical microtubules observed in the wild type. The mst12 mutant also failed to elicit localized host defence responses, including papilla formation and autofluorescence. Our data indicate that generation of appressorium turgor pressure and formation of the penetration peg are two independent processes. MST12 may play important roles in regulating penetration peg formation and directing the physical forces exerted by the appressorium turgor in mature appressoria.
Characterization of IDI‐4, a bZIP transcription factor inducing autophagy and cell death in the fungus Podospora anserina
Authors: Dementhon Karine , Saupe Sven J. , Clavé Corinne
Published: September 2004

In filamentous fungi a cell death reaction occurs when hyphae of unlike genotype fuse. This phenomenon is referred to as heterokaryon incompatibility. In Podospora anserina, this cell death reaction was found to be associated with the transcriptional induction of a set of genes termed idi genes (for induced during incompatibility) and activation of autophagy. Herein, we describe the characterization of idi‐4, a novel idi gene encoding a bZIP transcription factor. Expression of idi‐4 is induced during cell death by incompatibility and in various stress conditions. Inactivation of idi‐4 by gene replacement does not suppress incompatibility but we show that overexpression of idi‐4 triggers cell death. Strains which undergo idi‐4‐induced cell death display cytological hallmarks of cell death by incompatibility notably induction of autophagy. We also report that increased expression of idi‐4 leads to transcriptional induction of other idi genes such as idi‐7, the orthologue of the yeast ATG8 autophagy gene. Together these results establish IDI‐4 as one of the transcription factor regulating autophagy and cell fate in Podospora.
Endoplasmic reticulum stress leads to the selective transcriptional downregulation of the glucoamylase gene in Aspergillus niger
Authors: Al‐Sheikh Hashem , Watson Adrian J. , Lacey Georgina A. , Punt Peter J. , MacKenzie Donald A. , Jeenes David J. , Pakula Tiina , Penttilä Merja , Alcocer Marcos J. C. , Archer David B.
Published: September 2004

We describe a new endoplasmic reticulum (ER)‐associated stress response in the filamentous fungus Aspergillus niger. The inhibition of protein folding within the ER leads to cellular responses known collectively as the unfolded protein response (UPR) and we show that the selective transcriptional downregulation of the gene encoding glucoamylase, a major secreted protein, but not two non‐secreted proteins, is an additional consequence of ER stress. The transcriptional downregulation effect is shown by nuclear run‐on studies to be at the level of transcription, rather than mRNA stability, and is found to be mediated through the promoter of glaA in a region more than 1 kb upstream of the translational start. The inhibition of protein folding in the ER can be induced in a variety of ways. We examined the effects of dithiothreitol (DTT), a reducing agent that causes the formation of unfolded proteins. Although a general downregulation of transcription was seen with DTT treatment, we show that selective downregulation was observed with the glaA gene compared with genes encoding the non‐secreted proteins γ‐actin and glyceraldehyde 3′‐phosphate dehydrogenase. The DTT‐treated fungal cells also showed evidence for the induction of the UPR because expression of bipA and pdiA, encoding an ER‐resident chaperone and foldase, respectively, are upregulated and splicing of hacA, the gene encoding the transcription factor responsible for induction of the UPR, occurs allowing the production of an active HacA protein. As a preliminary attempt to investigate if the transcriptional downregulation effect was mediated through HacA (i.e. part of the UPR), we examined ER stress induced through antisense technology to lower the level of PDI in the ER of A. niger. Although the transcription of glaA was attenuated in that strain of A. niger, UPR was not evident, suggesting that the transcriptional downregulation mechanism is controlled differently from the UPR.
Ralstonia solanacearum genes induced during growth in tomato: an inside view of bacterial wilt
Authors: Brown Darby G. , Allen Caitilyn
Published: September 2004

The phytopathogen Ralstonia solanacearum has over 5000 genes, many of which probably facilitate bacterial wilt disease development. Using in vivo expression technology (IVET), we screened a library of 133 200 R. solanacearum strain K60 promoter fusions and isolated ≈ 900 fusions expressed during bacterial growth in tomato plants. Sequence analysis of 307 fusions revealed 153 unique in planta‐expressed (ipx) genes. These genes included seven previously identified virulence genes (pehR, vsrB, vsrD, rpoS, hrcC, pme and gspK) as well as seven additional putative virulence factors. A significant number of ipx genes may reflect adaptation to the host xylem environment; 19.6%ipx genes are predicted to encode proteins with metabolic and/or transport functions, and 9.8%ipx genes encode proteins possibly involved in stress responses. Many ipx genes (18%) encode putative transmembrane proteins. A majority of ipx genes isolated encode proteins of unknown function, and 13% were unique to R. solanacearum. The ipx genes were variably induced in planta; β‐glucuronidase reporter gene expression analysis of a subset of 44 ipx fusions revealed that in planta expression levels were between two‐ and 37‐fold higher than in culture. The expression of many ipx genes was subject to known R. solanacearum virulence regulators. Of 32 fusions tested, 28 were affected by at least one virulence regulator; several fusions were controlled by multiple regulators. Two ipx fusion strains isolated in this screen were reduced in virulence on tomato, indicating that gene(s) important for bacterial wilt pathogenesis were interrupted by the IVET insertion; mutations in other ipx genes are necessary to determine their roles in virulence and in planta growth. Collectively, this profile of ipx genes suggests that in its host, R. solanacearum confronts and overcomes a stressful and nutrient‐poor environment.
Complex spatial distribution and dynamics of an abundant Escherichia coli outer membrane protein, LamB
Authors: Gibbs Karine A. , Isaac Daniel D. , Xu Jun , Hendrix Roger W. , Silhavy Thomas J. , Theriot Julie A.
Published: September 2004

Advanced techniques for observing protein localization in live bacteria show that the distributions are dynamic. For technical reasons, most such techniques have not been applied to outer membrane proteins in Gram‐negative bacteria. We have developed two novel live‐cell imaging techniques to observe the surface distribution of LamB, an abundant integral outer membrane protein in Escherichia coli responsible for maltose uptake and for attachment of bacteriophage lambda. Using fluorescently labelled bacteriophage lambda tails, we quantitatively des‐cribed the spatial distribution and dynamic movement of LamB in the outer membrane. LamB accumulated in spiral patterns. The distribution depended on cell length and changed rapidly. The majority of the protein diffused along spirals extending across the cell body. Tracking single particles, we found that there are two populations of LamB – one shows very restricted diffusion and the other shows greater mobility. The presence of two populations recalls the partitioning of eukaryotic membrane proteins between ‘mobile’ and ‘immobile’ populations. In this study, we have demonstrated that LamB moves along the bacterial surface and that these movements are restricted by an underlying dynamic spiral pattern.
Fungicide activity through activation of a fungal signalling pathway
Authors: Kojima Kaihei , Takano Yoshitaka , Yoshimi Akira , Tanaka Chihiro , Kikuchi Taisei , Okuno Tetsuro
Published: September 2004

Fungicides generally inhibit enzymatic reactions involved in fungal cellular biosynthesis. Here we report, for the first time, an example of fungicidal effects through hyperactivation of a fungal signal transduction pathway. The OSC1 gene, encoding a MAP kinase (MAPK) related to yeast Hog1, was isolated from the fungal pathogen Colletotrichum lagenarium that causes cucumber anthracnose. The osc1 knockout mutants were sensitive to high osmotic stress and showed increased resistance to the fungicide fludioxonil, indicating that Osc1 is involved in responses to hyperosmotic stress and sensitivity to fludioxonil. The Osc1 MAPK is phosphorylated under high osmotic conditions, indicating activation of Osc1 by high osmotic stress. Importantly, fludioxonil treatment also activates phosphorylation of Osc1, suggesting that improper activation of Osc1 by fludioxonil has negative effects on fungal growth. In the presence of fludioxonil, the wild‐type fungus was not able to infect the host plant because of a failure of appressorium‐mediated penetration, whereas osc1 mutants successfully infected plants. Analysis using a OSC1‐GFP fusion gene indicated that Osc1 is rapidly translocated to the nucleus in appressorial cells after the addition of fludioxonil, suggesting that fludioxonil impairs the function of infection structures by activation of Osc1. Furthermore, fludioxonil activates Hog1‐type MAPKs in the plant pathogenic fungi Cochliobolus heterostrophus and Botrytis cinerea. These results strongly suggest that fludioxonil acts as a fungicide, in part, through activation of the MAPK cascade in fungal pathogens.
Hydraulic responses to height growth in maritime pine trees
Authors: DELZON S. , SARTORE M. , BURLETT R. , DEWAR R. , LOUSTAU D.
Published: September 2004

As trees grow taller, decreased xylem path conductance imposes a major constraint on plant water and carbon balance, and is thus a key factor underlying forest productivity decline with age. The responses of stomatal conductance, leaf area: sapwood area ratio (AL : AS) and soil–leaf water potential gradient (ΔΨS–L) to height growth were investigated in maritime pine trees. Extensive measurements ofin situsap flow, stomatal conductance and (non‐gravitational) needle water potential (L = ΨL − ρwgh) were made during 2 years in a chronosequence of four even‐aged stands, under both wet and dry soil conditions. Under wet soil conditions,Lwas systematically lower in taller trees on account of differences in gravitational potential. In contrast, under dry soil conditions, our measurements clearly showed thatLwas maintained above a minimum threshold value of −2.0 MPa independently of tree height, thus limiting the range of compensatory change in ΔΨS–L. Although a decrease in theAL : ASratio occurred with tree height, this compensation was not sufficient to prevent a decline in leaf‐specific hydraulic conductance,KL(50% lower in 30 m trees than in 10 m trees). An associated decline in stomatal conductance with tree height thus occurred to maintain a balance between water supply and demand. Both the increased investment in non‐productive versus productive tissues (AS : AL) and stomatal closure may have contributed to the observed decrease in tree growth efficiency with increasing tree height (by a factor of three from smallest to tallest trees), although other growth‐limiting responses (e.g. soil nutrient sequestration, increased respiratory costs) cannot be excluded.