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Little attention has been paid to the color change or chemical compositional changes that occur in grape stems and how this correlates with the berry ripening process. Recently we have found that the change in grape peduncle color of Shiraz (Vitis vinifera) from green at veraison to predominantly brown at harvest occurs in parallel with berry ripening and as such may represent a new way of assisting in the prediction of grape maturity and harvest date. We have now investigated further the link between certain key chemical compositional changes that occur in the grape stem (peduncle and rachis) from veraison to harvest and how these attributes correlate with the observed color change in the vineyard. We report that peduncle moisture content has an excellent linear correlation with the color hue value and is negatively correlated in a strong fashion with the chlorophyll and carotenoid pigment ratio (Ca+b/Cx+c) within the peduncles. Significant differences in the moisture content, total chlorophylls (including chlorophyll a and b levels), total carotenoids, total phenolics, and the antioxidant capacity (DPPH) levels between the peduncles and rachises were found as they evolve from veraison to harvest. Finally, we have demonstrated for the first time that peduncle moisture content codevelops with the prototypical berry ripeness parameters ( o Brix, pH, TA), which provides for the development of a new approach for viticulturists and winemakers to evaluate grape ripeness through peduncle moisture levels and therefore assist in harvest decision making.

This study describes the direct association of in vivo burn scar contraction with the level of α-smooth muscle actin (α-SMA) in scar tissue, in a porcine burn model. The expression of α-SMA was investigated in 100 biopsies from 44 6-week old burn scars and in 85 biopsies from 16 2-week old burn wounds. Statistical analysis showed that the levels of α-SMA in 6-week old scars were significantly negatively correlated to scar size (r=-0.68) and the higher levels of α-SMA were observed in smaller scars. Moreover, α-SMA was also found to be significantly positively correlated to re-epithelialisation time (r=0.57) and scar thickness (r=0.58) and higher levels of α-SMA were detected in thicker scars with delayed wound closure. Further statistical analysis revealed that scar contraction can be explained best by the level of α-SMA expression and partially by scar thickness. Other variables, such as different dressings and individual pig, may also partly contribute to scar contraction. At week 2 after-burn, the level of α-SMA expression in 16 burn wounds was significantly related to the depth of burns and wound healing outcome. To our knowledge, this is the first study to provide in vivo evidence of the association of α-SMA expression with scar contraction, scar thickness, re-epithelialisation time and the depth of burn in a large animal burn model with scars similar to human hypertrophic scar., (Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.)

Background: MPC 80 is a high-protein (80%) milk powder commonly used in the food industry as a functional ingredient and valued for its nutritional quality. However, its rehydration properties decline during storage, causing more time to be required for rehydration of the powder by the end user. It is thought that changes at the surface of the powder particles contribute to this reduced solubility during storage., Results: Surface composition and structural changes in milk protein concentrate (MPC) were observed during 90 days of storage at temperatures of 25 and 40 °C and relative humidities of 44, 66 and 84%. No significant changes to the surface composition (fat, protein and lactose) of the MPC powder samples occurred during storage; however, some changes in the microstructure of the powders were observed. Scanning electron microscopy analysis of the powder particles during dissolution showed the formation of a crust, consisting of a thin layer of fused casein micelles, on the surface of the stored powders. An increase in the hydrophobicity at the surface of the particles was evident by X-ray photoelectron spectroscopy analysis of the bonding state of the elements at or near the surface and by atomic force microscopy measurements of the adherence of particles to the surface of a material., Conclusion: The development of this 'crust' is thought to contribute to the decrease in the solubility of the powder particles during storage. The increase in the hydrophobicity at the surface and the casein micelle interactions resulting in the surface crust formation appear to contribute to the decrease in the solubility of MPC during storage., (Copyright © 2011 Society of Chemical Industry.)

Transgenic insects are a promising tool in sterile insect techniques and population replacement strategies. Such transgenic insects can be created using nonautonomous transposons, which cannot be transferred without a transposase source. In biocontrol procedures where large numbers of insects are released, there is increased risk of transgene remobilization caused by external transposase sources that can alter the characteristics of the transgenic organisms lead horizontal transgene transfer to other species. Here we describe a novel, effective method for transgene stabilization based on the introduction of directed double-strand breaks (DSB) into a genome-integrated sequence and their subsequent repair by the single-strand annealing (SSA) pathway. Due to the construct's organization, the repair pathway is predictable, such that all transposon and marker sequences can be deleted, while preserving integration of exogenous DNA in the genome. The exceptional conservation of DNA repair pathways makes this method suitable for a broad range of organisms.

This study describes the ultrasound assessment of burn scars in paediatric patients and the association of these scar thickness with laser Doppler imaging (LDI) determined burn depth. A total of 60 ultrasound scar assessments were conducted on 33 scars from 21 paediatric burn patients at 3, 6 and 9 months after-burn. The mean of peak scar thickness was 0.39±0.032 cm, with the thickest at 6 months (0.40±0.036 cm). There were 17 scald burn scars (0.34±0.045 cm), 4 contact burn scars (0.61±0.092 cm), and 10 flame burn scars (0.42±0.058 cm). Each group of scars followed normal distributions. Twenty-three scars had original burns successfully scanned by LDI and various depths of burns were presented by different colours according to blood perfusion units (PU), with dark blue <125, light blue 125-250, and green 250-440 PU. The thickness of these scars was significantly different between the predominant colours of burns, with the thinnest scars for green coloured burns and the thickest for dark blue coloured burns. Within light blue burns, grafted burns healed with significantly thinner scars than non-grafted burns. This study indicates that LDI can be used for predicting the risk of hypertrophic scarring and for guiding burn care. To our knowledge, this is the first study to correlate the thickness of burns scars by ultrasound scan with burn depth determined by LDI., (Copyright © 2010 Elsevier Ltd and ISBI. All rights reserved.)

Using our porcine model of deep dermal partial thickness burn injury, various durations (10min, 20min, 30min or 1h) and delays (immediate, 10min, 1h, 3h) of 15 degrees C running water first aid were applied to burns and compared to untreated controls. The subdermal temperatures were monitored during the treatment and wounds observed weekly for 6 weeks, for re-epithelialisation, wound surface area and cosmetic appearance. At 6 weeks after the burn, tissue biopsies were taken of the scar for histological analysis. Results showed that immediate application of cold running water for 20min duration is associated with an improvement in re-epithelialisation over the first 2 weeks post-burn and decreased scar tissue at 6 weeks. First aid application of cold water for as little as 10min duration or up to 1h delay still provides benefit.

This is a study to compare wound healing among three types of dressings on a porcine model with deep-dermal-partial-thickness burns. The burns in this study were from eight animal trials conducted in the past for other purposes and only burns with a uniform pale appearance that had served as controls in original experiments were selected. In total, there were 57 burns in 33 pigs, using one of following three dressings: Acticoat (Silver) (3 trials), Jelonet (Gauze) (3 trials), and Solosite Gel/Jelonet (Gel/Gauze) (2 trials). The wound healing assessments included wound re-epithelialisation during a 6-week period, clinical and histological scar assessments at week 6 after burn. Of all wound healing/scar assessments, only re-epithelialisation showed statistical difference between dressings. Earlier re-epithelialisation was observed in Gel/Gauze dressings compared to Silver and/or Gauze dressings. However, this study revealed huge variation in wound healing outcome between 3 trials within both Silver and/or Gauze dressings, supported by significant differences on re-epithelialisation, clinical and histological scar measurements. In addition, it was found that larger animals healed better than smaller ones, based on weights from 21 pigs. Of all dressings, Silver delivers the best protection for wound colonization/infection. Wound colonization/infection was found to confine wound healing and lead to thinner RND in scars. From this study, we cannot find enough evidence to suggest the beneficial effect of one dressing(s) over others on burn wound healing outcome on a porcine model with small deep-dermal-partial-thickness burns with a relative small sample size.

Autophagy is activated in response to cellular stressors and mediates lysosomal degradation and recycling of cytoplasmic material and organelles as a temporary cell survival mechanism. Defective autophagy is implicated in human pathology, as disruption of protein and organelle homeostasis enables disease-promoting mechanisms such as toxic protein aggregation, oxidative stress, genomic damage, and inflammation. We previously showed that autophagy-defective immortalized mouse mammary epithelial cells are susceptible to metabolic stress, DNA damage, and genomic instability. We now report that autophagy deficiency is associated with endoplasmic reticulum (ER) and oxidative stress, and with deregulation of p62-mediated keratin homeostasis in mammary cells, allograft tumors, and mammary tissues from genetically engineered mice. In human breast tumors, high phospho(Ser73)-K8 levels are inversely correlated with Beclin 1 expression. Thus, autophagy preserves cellular fitness by limiting ER and oxidative stress, a function potentially important in autophagy-mediated suppression of mammary tumorigenesis. Furthermore, autophagy regulates keratin homeostasis in the mammary gland via a p62-dependent mechanism. High phospho(Ser73)-K8 expression may be a marker of autophagy functional status in breast tumors and, as such, could have therapeutic implications for breast cancer patients.

This study describes the first aid used and clinical outcomes of all patients who presented to the Royal Children's Hospital, Brisbane, Australia in 2005 with an acute burn injury. A retrospective audit was performed with the charts of 459 patients and information concerning burn injury, first-aid treatment, and clinical outcomes was collected. First aid was used on 86.1% of patients, with 8.7% receiving no first aid and unknown treatment in 5.2% of cases. A majority of patients had cold water as first aid (80.2%), however, only 12.1% applied the cold water for the recommended 20 minutes or longer. Recommended first aid (cold water for >or=20 minutes) was associated with significantly reduced reepithelialization time for children with contact injuries (P=.011). Superficial depth burns were significantly more likely to be associated with the use of recommended first aid (P=.03). Suboptimal treatment was more common for children younger than 3.5 years (P<.001) and for children with friction burns. This report is one of the few publications to relate first-aid treatment to clinical outcomes. Some positive clinical outcomes were associated with recommended first-aid use; however, wound outcomes were more strongly associated with burn depth and mechanism of injury. There is also a need for more public awareness of recommended first-aid treatment.

Objective: Laser Doppler imaging (LDI) was compared to wound outcomes in children's burns, to determine if the technology could be used to predict these outcomes., Methods: Forty-eight patients with a total of 85 burns were included in the study. Patient median age was 4 years 10 months and scans were taken 0-186 h post-burn using the fast, low-resolution setting on the Moor LDI2 laser Doppler imager. Wounds were managed by standard practice, without taking into account the scan results. Time until complete re-epithelialisation and whether or not grafting and scar management were required were recorded for each wound. If wounds were treated with Silvazine or Acticoat prior to the scan, this was also recorded., Results: The predominant colour of the scan was found to be significantly related to the re-epithelialisation, grafting and scar management outcomes and could be used to predict those outcomes. The prior use of Acticoat did not affect the scan relationship to outcomes, however, the use of Silvazine did complicate the relationship for light blue and green scanned partial thickness wounds. Scans taken within the 24-h window after-burn also appeared to be accurate predictors of wound outcome., Conclusion: Laser Doppler imaging is accurate and effective in a paediatric population with a low-resolution fast-scan.

Background: Silver dressings have been widely and successfully used to prevent cutaneous wounds, including burns, chronic ulcers, dermatitis and other cutaneous conditions, from infection. However, in a few cases, skin discolouration or argyria-like appearances have been reported. This study investigated the level of silver in scar tissue post-burn injury following application of Acticoat, a silver dressing., Methods: A porcine deep dermal partial thickness burn model was used. Burn wounds were treated with this silver dressing until completion of re-epithelialization, and silver levels were measured in a total of 160 scars and normal tissues., Results: The mean level of silver in scar tissue covered with silver dressings was 136 microg/g, while the silver level in normal skin was less than 0.747 microg/g. A number of wounds had a slate-grey appearance, and dissection of the scars revealed brown-black pigment mostly in the middle and deep dermis within the scar. The level of silver and the severity of the slate-grey discolouration were correlated with the length of time of the silver dressing application., Conclusions: These results show that silver deposition in cutaneous scar tissue is a common phenomenon, and higher levels of silver deposits and severe skin discolouration are correlated with an increase in the duration of this silver dressing application., ((c) 2009 John Wiley & Sons A/S.)

This study describes the evaluation of a clinical scar scale for our porcine burn scars, which includes scar cosmetic outcome, colour, height and hair, supplemented with reference porcine scar photographs representing each scar outcome and scar colour scores. A total of 72 porcine burn scars at week 6 after burn were rated in vivo and/or on photographs. Good agreements were achieved for both intra-rater reliability (correlation is 0.86-0.98) and inter-rater reliability (ICC=80-85%). The results showed statistically significant correlations for each pair in this clinical scar scale (p<0.01), with the best correlation found between scar cosmetic outcome and scar colour. A multivariate principle components analysis revealed that this clinical scar assessment was highly correlated with scar histology, wound size, and re-epithelialisation data (p<0.001). More severe scars are clinically characterised by darker purple colouration, more elevation, no presence of hair, histologically by thicker scar tissue, thinner remaining normal dermis, are more likely to have worse contraction, and slower re-epithelialisation. This study demonstrates that our clinical scar scale is a reliable, independent and valuable tool for assessing porcine burn outcome and truthfully reflects scar appearance and function. To our knowledge, this is the first study demonstrating a high correlation between clinical scar assessment and scar histology, wound contraction and re-epithelialisation data on porcine burn scars. We believe that the successful use of porcine scar scales is invaluable for assessing potential human burn treatments.

Silver dressings have been widely used to successfully prevent burn wound infection and sepsis. However, a few case studies have reported the functional abnormality and failure of vital organs, possibly caused by silver deposits. The aim of this study was to investigate the serum silver level in the pediatric burn population and also in several internal organs in a porcine burn model after the application of Acticoat. A total of 125 blood samples were collected from 46 pediatric burn patients. Thirty-six patients with a mean of 13.4% TBSA burns had a mean peak serum silver level of 114 microg/L, whereas 10 patients with a mean of 1.85% TBSA burns had an undetectable level of silver (<5.4 microg/L). Overall, serum silver levels were closely related to burn sizes. However, the highest serum silver was 735 microg/L in a 15-month-old toddler with 10% TBSA burns and the second highest was 367 microg/L in a 3-year old with 28% TBSA burns. In a porcine model with 2% TBSA burns, the mean peak silver level was 38 microg/L at 2 to 3 weeks after application of Acticoat and was then significantly reduced to an almost undetectable level at 6 weeks. Of a total of four pigs, silver was detected in all four livers (1.413 microg/g) and all four hearts (0.342 microg/g), three of four kidneys (1.113 microg/g), and two of four brains (0.402 microg/g). This result demonstrated that although variable, the level of serum silver was positively associated with the size of burns, and significant amounts of silver were deposited in internal organs in pigs with only 2% TBSA burns, after application of Acticoat.

This retrospective review examines healing in different sites on a porcine burn model; 24 pairs of burns on 18 pigs from other animal trials were selected for analysis. Each pair of burns was located on the either the cranial or the caudal part of the thoracic ribs region, on the same side of the animal. The burns were 40-50 cm(2) in size and of uniform deep-dermal partial thickness. Caudal burns healed significantly better than cranial burns, demonstrated by earlier closure of wounds, less scar formation and better cosmesis. To our knowledge, this is the first detailed study reporting that burn healing is affected by location on a porcine burn model. We recommend that similar symmetrical burns should be used for future comparative assessments of burn healing.

Many alternative therapies are used as first aid treatment for burns, despite limited evidence supporting their use. In this study, Aloe vera, saliva and a tea tree oil impregnated dressing (Burnaid) were applied as first aid to a porcine deep dermal contact burn, compared to a control of nothing. After burn creation, the treatments were applied for 20 min and the wounds observed at weekly dressing changes for 6 weeks. Results showed that the alternative treatments did significantly decrease subdermal temperature within the skin during the treatment period. However, they did not decrease the microflora or improve re-epithelialisation, scar strength, scar depth or cosmetic appearance of the scar and cannot be recommended for the first aid treatment of partial thickness burns.

In thermal deep-dermal burns, surgical debridement is normally used in conjunction with skin grafting or skin substitutes and debridement alone as a burn treatment is not usually practiced. The current study addresses whether or not debridement alone would enhance burn wound healing on small deep-dermal-partial thickness burns. This was a prospective and blinded experimental trial using a porcine deep-dermal-partial thickness burn model. Four burns, approximately 50 cm(2) in size, were created on each of eight pigs. Two burns from each pig were immediately surgically debrided and the other two were not debrided as the internal control. Hydrate gel together with paraffin gauze were used to cover the burns for four pigs and silver dressings for the other four. Clinical assessment of wound healing was conducted over a 6-week period. Skin samples were collected at the end of the experiment and histopathological evaluation was performed. The results show thinner scar formation and lower scar height in the debrided compared with nondebrided wounds in the hydrate gel/paraffin gauze groups. There were no statistically significant differences in wound healing assessment between the debrided and nondebrided wounds dressed with silver dressings. This study provides supporting evidence that immediate debridement with an appropriate dressing and without skin grafting may promote wound healing, suggesting its potential benefit for clinical patients.

The structure of starch molecules is relevant to nutrition and industrial applications. Size-exclusion chromatography (SEC, also known as GPC) of native starch generally suffers non-satisfactory repeatability and reproducibility of the dissolution and separation. This work combines two polar organic solvents: dimethylsulfoxide for complete dissolution and dimethylacetamide to limit shear degradation. The separation is as repeatable as that of polystyrene standards performing dissolution and separation at 80 degrees C. Successful covalent-labeling on the glucose unit is claimed to be published here for the first time in non-degradative conditions and allows the use of UV detector with significantly higher sensitivity than with a refractometer.

Using our porcine model of deep dermal partial thickness burn injury, various cooling techniques (15 degrees C running water, 2 degrees C running water, ice) of first aid were applied for 20 minutes compared with a control (ambient temperature). The subdermal temperatures were monitored during the treatment and wounds observed and photographed weekly for 6 weeks, observing reepithelialization, wound surface area and cosmetic appearance. Tissue histology and scar tensile strength were examined 6 weeks after burn. The 2 degrees C and ice treatments decreased the subdermal temperature the fastest and lowest, however, generally the 15 and 2 degrees C treated wounds had better outcomes in terms of reepithelialization, scar histology, and scar appearance. These findings provide evidence to support the current first aid guidelines of cold tap water (approximately 15 degrees C) for 20 minutes as being beneficial in helping to heal the burn wound. Colder water at 2 degrees C is also beneficial. Ice should not be used.

Topical administration of growth factors has displayed some potential in wound healing, but variable efficacy, high doses, and costs have hampered their implementation. Moreover, this approach ignores the fact that wound repair is driven by interactions between multiple growth factors and extracellular matrix (ECM) proteins. We report herein that complexes comprising IGF and IGF-binding proteins bound to the ECM protein vitronectin (VN) significantly enhance cellular functions relevant to wound repair in human skin keratinocytes in two- and three-dimensional in vitro cell models and are active, even in the presence of wound fluid. Moreover, these responses require activation of both the IGF receptor and the VN-binding alpha(v) integrins. Further, we assessed the complexes as a topical agent in the treatment of deep dermal partial thickness burns in a porcine model. This pilot study revealed that the complexes may hold promise as a wound healing therapy. Critically, the significant responses observed in vitro and the encouraging preliminary data in vivo were obtained with nanogram doses of growth factors. This suggests that coupling delivery of growth factors to ECM proteins such as VN may ultimately prove to be a more effective strategy for developing a wound healing therapy.

Background: Patients with cleft lip and/or palate (CL&/P) experience a higher caries prevalence. This study aimed to determine if patients with CL&/P, undergoing and not undergoing orthodontic treatment, have a different salivary biochemical profile and different salivary levels of Mutans Streptococci (MS) and Lactobacilli (LB) compared to patients undergoing and not undergoing orthodontic treatment without CL&/P., Methods: One hundred and ten subjects aged between 12 and 17 years were recruited into one of four different groups comprising two control groups and two treatment groups. The control groups comprised of subjects with and without CL&/P who were not undergoing orthodontic treatment. The treatment groups comprised of subjects with and without CL&/P undergoing orthodontic treatment. Regular reinforcement of oral hygiene instructions, dietary counselling and debridement, when necessary, were offered to subjects in the treatment groups following their orthodontic adjustment appointments. The salivary secretion time, pH of resting and stimulated saliva, salivary flow rate, buffering capacity, quantity of salivary MS and LB were measured., Results: Subjects with CL&/P undergoing orthodontic treatment at the Children's Oral Health Service tended to present with microbiological and salivary profiles that were less favourable for caries development. There was a significant difference in the percentage of subjects with > or = 10(5) colony forming units (CFU)/mL of MS between the cleft treatment and non-cleft treatment groups. Subjects in the non-cleft treatment group had the highest percentage of subjects (86.7 per cent) with > or = 10(5) CFU/mL of MS whereas subjects in the cleft treatment group had the lowest percentage of subjects (60 per cent) with > or = 10(5) CFU/mL of MS. For LB, there were significantly higher percentages of subjects with > or =10(5) CFU/mL of LB in the non-cleft treatment (76.7 per cent) and cleft treatment (73.3 per cent) groups compared to the non-cleft control (46.7 per cent) and cleft control (40.0 per cent) groups., Conclusions: Regular oral hygiene reinforcement and dental health education appears to have a positive effect in reducing the percentage of subjects with > or = 10(5) CFU/mL of MS.

Autophagy is a catabolic process involving self-digestion of cellular organelles during starvation as a means of cell survival; however, if it proceeds to completion, autophagy can lead to cell death. Autophagy is also a haploinsufficient tumor suppressor mechanism for mammary tumorigenesis, as the essential autophagy regulator beclin1 is monoallelically deleted in breast carcinomas. However, the mechanism by which autophagy suppresses breast cancer remains elusive. Here we show that allelic loss of beclin1 and defective autophagy sensitized mammary epithelial cells to metabolic stress and accelerated lumen formation in mammary acini. Autophagy defects also activated the DNA damage response in vitro and in mammary tumors in vivo, promoted gene amplification, and synergized with defective apoptosis to promote mammary tumorigenesis. Therefore, we propose that autophagy limits metabolic stress to protect the genome, and that defective autophagy increases DNA damage and genomic instability that ultimately facilitate breast cancer progression.

Background: Inferior periodontal and pulpal outcomes may follow surgical exposure of palatally impacted maxillary canines., Objectives: To compare the periodontal and pulpal health of palatally impacted maxillary canines following either surgical exposure and assisted eruption (SE) or unassisted eruption following extraction of the overlying deciduous canine and orthodontic creation of space in the arch (OT)., Methods: Twenty-eight subjects (OT group: N = 14; SE group: N = 14) with unilateral palatally impacted canines were examined at least six months after orthodontic treatment. The gingival index score, plaque index score, pocket depth, attachment loss, tenderness to percussion, pulpal responses to stimuli and radiographic assessment of changes in the pulpal cavities and peri-radicular areas were collected on the maxillary canines, lateral incisors and premolars. The contralateral teeth were used as controls., Results: There were no significant differences in the plaque index scores, the gingival index scores or the periodontal outcomes between the impacted canines in the two groups (SE and OT). More impacted canines than control canines had lost some periodontal attachment in the SE group (p = 0.004). Although more lateral incisors, canines and premolars on the impacted side had partially obliterated pulps than the corresponding teeth on the control side, the teeth in both groups had similar pulpal responses (p = 0.064)., Conclusions: Natural eruption and conservative surgical exposure with orthodontic alignment have minor effects on the periodontium. Impacted canines treated surgically and non-surgically had a higher prevalence of pulpal changes than the control canines. Ultimately, the choice of treatment may depend on the clinical indications, the patient's and the orthodontist's preferences.

Background: Palatally impacted maxillary canines may appear unsightly after treatment because of changes in position and colour., Aim: To determine if palatally impacted canines treated either by surgical exposure and orthodontic repositioning or by creation of space in the arch and unassisted eruption have different aesthetic outcomes., Methods: Twenty eight subjects with unilateral palatally impacted canines who had completed orthodontic treatment at least 6 months previously were recruited from three specialist practices. In 14 subjects the canines had been treated by surgical exposure, orthodontic extrusion and repositioning in the arch (SE group) and in the remainder the deciduous canines were extracted and excess space created in the arch for the canines to erupt naturally (OT group). The contralateral canines were used as controls. The mean pretreatment ages of the subjects in the SE and OT groups were 13.5 (SD:1.6) years and 13.5 (SD:1.3) years respectively. The position and colour of the canines were assessed on post-treatment study models and 35 mm slides using the American Board of Orthodontics Objective Grading System (ABO OGS) and subjective appraisal by two orthodontists. Each subject used a semantic scale to rate the aesthetic outcome of treatment., Results: Sixty four per cent of the treated canines in the SE group were significantly more 'intruded' than the treated canines in the OT group (p = 0.004) and the control canines (p = 0.004). The ABO OGS grades of the canines in the SE and OT groups were similar (p = 0.173). While the assessors detected a lack of labial root torque and gingival margin changes in the canines in the SE group, the subjects in both groups were satisfied with the appearance of the canines post-treatment., Conclusions: Palatally impacted canines treated by surgical exposure, extrusion and orthodontic treatment were more likely to be displaced vertically ('intruded') after treatment than palatally impacted canines treated by extraction of the overlying deciduous canines and creation of excess space in the arch. Small occlusal and aesthetic changes detected by the orthodontists, but not the ABO OGS, did not appear to detract from the satisfaction of the subjects with the results of orthodontic treatment.

Objective: To determine if the type of ligation influences the frictional resistance between stainless steel wire and brackets when the wire is subjected to repeated vertical displacements., Methods: Eight different types of ligation were used to secure a length of stainless steel wire in three stainless steel twin brackets. The wire was subjected to repeated vertical displacements in a simulated extraction space. Eighty per cent of the minimum force required to overcome static friction (F-m) between the wire and brackets was applied to the wire for eight minutes and any sliding measured., Results: Frictional resistance to sliding was least when stainless steel ligatures twisted in a figure 8 pattern until taut then untwisted one quarter turn were used, and greatest when elastomeric modules in a figure 8 pattern (EM8) were used. The F-m difference between fully engaged standard and Super Slick elastomeric modules was significantly different (p = 0.007). The frictional resistance to sliding fell when the wire was secured with either of these two methods and subjected to vertical displacement loads. There was no significant difference in the rate of wire movement between these modules., Conclusion: Repeated vertical displacement reduced the frictional resistance to sliding for all methods of ligation except EM8.

The Suppressor of the Hairy wing [Su(Hw)] binding region within the gypsy retrotransposon is the best known chromatin insulator in Drosophila melanogaster. According to previous data, two copies of the gypsy insulator inserted between an enhancer and a promoter neutralize each other's actions, which is indicative of an interaction between the protein complexes bound to the insulators. We have investigated the role of pairing between the gypsy insulators located on homologous chromosomes in trans interaction between yellow enhancers and a promoter. It has been shown that trans activation of the yellow promoter strongly depends on the site of the transposon insertion, which is evidence for a role of surrounding chromatin in homologous pairing. The presence of the gypsy insulators in both homologous chromosomes even at a distance of 9 kb downstream from the promoter dramatically improves the trans activation of yellow. Moreover, the gypsy insulators have proved to stabilize trans activation between distantly located enhancers and a promoter. These data suggest that gypsy insulator pairing is involved in communication between loci in the Drosophila genome.

Telomeres of Drosophila melanogaster contain arrays of the retrotransposon-like elements HeT-A and TART. Their transposition to broken chromosome ends has been implicated in chromosome healing and telomere elongation. We have developed a genetic system which enables the determination of the frequency of telomere elongation events and their mechanism. The frequency differs among lines with different genotypes, suggesting that several genes are in control. Here we show that the Su(var)2-5 gene encoding heterochromatin protein 1 (HP1) is involved in regulation of telomere length. Different Su(var)2-5 mutations in the heterozygous state increase the frequency of HeT-A and TART attachment to the broken chromosome end by more than a hundred times. The attachment occurs through either HeT-A/TART transposition or recombination with other telomeres. Terminal DNA elongation by gene conversion is greatly enhanced by Su(var)2-5 mutations only if the template for DNA synthesis is on the same chromosome but not on the homologous chromosome. The Drosophila lines bearing the Su(var)2-5 mutations maintain extremely long telomeres consisting of HeT-A and TART for many generations. Thus, HP1 plays an important role in the control of telomere elongation in D. melanogaster.