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Electronic cigarettes (E-cigarettes) have become increasingly popular around the world. Currently, dental professionals' knowledge and attitudes are varied with many clinicians unclear regarding the impact of E-cigarette products on the oral and general health of their patients. With developing social and health-related challenges, advice of dental and medical associations and other regulatory bodies on E-cigarette use is changing. Growing evidence demonstrating the risks of E-cigarette usage has prompted a review of legislation in the United Kingdom (UK), United States of America (USA), Australia and Canada to include the sale and availability of E-cigarettes, particularly those containing nicotine. Further consideration within the scientific and public health community is being given to assessing demographic usage patterns particularly uptake by non-smokers and adolescents, efficacy as a cessation tool, the impact of vapour on bystanders and direct injuries via explosions as well as emerging lung injuries. This article aims to provide a summary of the most up to date evidence relating to E-cigarette use, the latest position of dental associations and the oral health implications of E-cigarettes compared to conventional smoking. The article also aims to collate this information in order to provide dental clinicians with guidance on how to advise patients, specifically in answering common questions posed regarding E-cigarette use.

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Osteoradionecrosis (ORN) is an infrequent but serious complication of radiotherapy, especially in the head and neck region. It is a slowly progressive condition, with management in the early stages focused on symptom control, and surgery usually reserved for advanced ORN. However, established ORN is difficult to treat. The role of hyperbaric oxygen therapy has recently been contested. The use of pentoxifylline in the management of ORN was first described by Delanian in 2004, but its benefits have not been replicated in other studies. In cases of advanced ORN with pathological fractures, many centres still advocate surgical resection and reconstruction. However, in this group of patients who often have multiple medical comorbidities, many of whom have previously undergone significant surgery, a resective plan is not always ideal. This paper presents two successful cases of bony union after the use of pentoxifylline and tocopherol to manage grade III ORN of the mandible. Both patients had pathological fractures and orocutaneous fistulas and were deemed unsuitable for surgery. The possible reasons for the success of pentoxifylline and tocopherol are discussed, and a review of the current literature evidence of similar cases is presented. Pentoxifylline and tocopherol should be considered for the management of advanced ORN where surgical management is not appropriate.

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BACKGROUND: Temporomandibular disorders (TMD) cover a wide spectrum of disorder; myalgic, arthralgic and psychogenic. The procedure of TMJ arthrocentesis has a role in managing patients with arthralgic pain and limitation if they fail to respond to non-surgical therapy. METHOD: The patient records of a single private specialist OMS were searched over the 9-year period of 2006-2014 to identify patients who had arthrocentesis as part of their multidisciplinary management. The detailed demographic, diagnosis, pre and post arthrocentesis procedure were identified and put on a database. Appropriate statistics were performed. RESULTS: Seventy-six patients had 115 arthrocentesis procedures performed in the study period. Fifty of 76 had improvement in their pain and 16 of 41 had an increased jaw opening of more than 10 mm. There were no complications or morbidity. Analysis of patient variables generally showed no correlations. CONCLUSIONS: Temporomandibular joint arthrocentesis has a role in the multidisciplinary, multimodality treatment of arthralgic TMD.

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Large-scale atmospheric circulation controls the mass and energy balance of the Greenland ice sheet through its impact on radiative budget, runoff and accumulation. Here, using reanalysis data and the outputs of a regional climate model, we show that the persistence of an exceptional atmospheric ridge, centred over the Arctic Ocean, was responsible for a poleward shift of runoff, albedo and surface temperature records over the Greenland during the summer of 2015. New records of monthly mean zonal winds at 500 hPa and of the maximum latitude of ridge peaks of the 5,700±50 m isohypse over the Arctic were associated with the formation and persistency of a cutoff high. The unprecedented (1948-2015) and sustained atmospheric conditions promoted enhanced runoff, increased the surface temperatures and decreased the albedo in northern Greenland, while inhibiting melting in the south, where new melting records were set over the past decade.

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Alloreactive memory T cells mediate accelerated allograft rejection and transplant tolerance resistance. Recent studies have shown that B cell deficient-µMT mice fail to mount donor-specific memory T cell responses after transplantation. At the same time, other studies showed that pretransplant B cell depletion using rituximab (IgG1 anti-CD20 mAb) combined with cyclosporine A promoted the survival of islet allografts in monkeys. In this study, we investigated the effect of anti-CD20 antibody-mediated B cell depletion on the memory T cell alloresponse in mice. Wild-type and anti-OVA TCR transgenic mice were treated with an IgG2a anti-CD20 monoclonal antibody, which depleted nearly all B cells in the peripheral blood and secondary lymphoid organs but spared some B cells in the bone marrow. B cell depletion did not affect the direct alloresponse but resulted in a marked increase of indirect alloresponse after skin transplantation of naïve mice. Furthermore, in allosensitized mice, anti-CD20 mAb treatment enhanced the reactivation of allospecific memory T cells and accelerated second set rejection of skin allografts. This suggests that the effect of anti-CD20 antibodies on alloimmunity and allograft rejection might vary upon the nature of the antibodies as well as the circumstances under which they are delivered.

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The purpose of this study was to determine patient-reported outcomes of patients with mild to moderate developmental dysplasia of the hip (DDH) and femoroacetabular impingement (FAI) undergoing arthroscopy of the hip in the treatment of chondrolabral pathology. A total of 28 patients with a centre-edge angle between 15° and 19° were identified from an institutional database. Their mean age was 34 years (18 to 53), with 12 female and 16 male patients. All underwent labral treatment and concomitant correction of FAI. There were nine reoperations, with two patients requiring revision arthroscopy, two requiring periacetabular osteotomy and five needing total hip arthroplasty. Patients who required further major surgery were more likely to be older, male, and to have more severe DDH with a larger alpha angle and decreased joint space. At a mean follow-up of 42 months (24 to 89), the mean modified Harris hip score improved from 59 (20 to 98) to 82 (45 to 100; p < 0.001). The mean Western Ontario and McMaster Universities Osteoarthritis Index score improved from 30 (1 to 61) to 16 (0 to 43; p < 0.001). Median patient satisfaction was 9.0/10 (1 to 10). Patients reported excellent improvement in function following arthroscopy of the hip. This study shows that with proper patient selection, arthroscopy of the hip can be successful in the young patient with mild to moderate DDH and FAI.

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Modulation of the tumour microvasculature has been demonstrated to affect the effectiveness of radiation, stimulating the search for anti-angiogenic and vascular-disrupting treatment modalities. Microbubbles stimulated by ultrasound have recently been demonstrated as a radiation enhancer when used with different cancer models including PC3. Here, photoacoustics imaging technique was used to assess this treatment's effects on haemoglobin levels and oxygen saturation. Correlations between this modality and power doppler assessments of blood flow, and histology measurements of vascular integrity and cell death were also investigated. Xenograft prostate tumours in SCID mice were treated with 0, 2, or 8 Gy radiation combined with microbubbles exposed to 500 kHz ultrasound at a peak negative pressure of 0, 570, and 750 kPa. Tumours were assessed and levels of total haemoglobin, oxygen saturation were measured using photoacoustics before and 24 hours after treatment along with power doppler measured blood flow. Mice were then sacrificed and tumours were assessed for cell death and vascular composition using immunohistochemistry. Treatments using 8 Gy and microbubbles resulted in oxygen saturation decreasing by 28 ± 10% at 570 kPa and 25 ± 29% at 750 kPa, which corresponded to 44 ± 9% and 40 ± 14% respective decreases in blood flow as measured with power doppler. Corresponding histology indicated 31 ± 5% at 570 kPa and 37 ± 5% at 750 kPa in terms of cell death. There were drops in intact vasculature of 15 ± 2% and 20 ± 2%, for treatments at 570 kPa and 750 kPa. In summary, photoacoustic measures of total haemoglobin and oxygen saturation paralleled changes in power doppler indicators of blood flow. Destruction of tumour microvasculature with microbubble-enhanced radiation also led to decreases in blood flow and was associated with increases in cell death and decreases in intact vasculature as detected with CD31 labeling.

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Using 3D Finite-Difference-Time-Domain simulations, we study the morphology of the laser-created damage inside fused silica. Among the competing effects limiting the intensity in the dielectric, we find the most important is the pulse defocusing by the plasma lens, partially balanced by the Kerr effect. Less important are collisional energy dissipation and laser depletion by multi-photon absorption. We also found that the profile of generated plasma is asymmetrical in the transverse cross-section, with the plasma extended along the direction perpendicular to the laser polarization.

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The tumor suppressor gene hypermethylated in cancer 1 (HIC1), which encodes a transcriptional repressor, is epigenetically inactivated in various human cancers. In this study, we show that HIC1 is a direct transcriptional repressor of the gene encoding ephrin-A1, a cell surface ligand implicated in the pathogenesis of epithelial cancers. We also show that mouse embryos lacking both Hic1 alleles manifest developmental defects spatially associated with the misexpression of ephrin-A1, and that overexpression of ephrin-A1 is a feature of tumors arising in Hic1 heterozygous mice in which the remaining wild-type allele is epigenetically silenced. In breast cancer, we find that ephrin-A1 expression is common in vivo, but that in cell culture, expression of the EphA receptors is predominant. Restoration of HIC1 function in breast cancer cells leads to a reduction in tumor growth in vivo, an effect that can be partially rescued by co-overexpression of ephrin-A1. Interestingly, overexpression of ephrin-A1 in vitro triggers downregulation of EphA2 and EphA4 levels, resulting in an expression pattern similar to that seen in vivo. We conclude that Hic1 spatially restricts ephrin-A1 expression in development, and that upregulated expression of ephrin-A1 resulting from epigenetic silencing of HIC1 in cancer cells may be an important mechanism in epithelial malignancy.

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Treatment of osteoarthritis in young and middle-aged patients, in whom joint replacement is usually not appropriate, is a challenge to orthopaedic surgeons. Arthroscopic techniques can help control patients' symptoms. In particular, the microfracture procedure combined with management of the joint volume and a specific rehabilitation protocol shows good results in patients with osteoarthritis and cartilage defects by resurfacing the defect with a combination of types I and II cartilaginous tissue. Microfracture is a single-staged arthroscopic procedure that can be combined with any other arthroscopic treatment for osteoarthritis of the knee. With an appropriate rehabilitation protocol and techniques for controlling the joint volume, these treatments are very effective for pain relief and functional improvement. The described technique is our choice for initial surgical treatment of osteoarthritis of the knee.

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Over an eight-month period we prospectively enrolled 122 patients who underwent arthroscopic surgery of the hip for femoroacetabular impingement and met the inclusion criteria for this study. Patients with bilateral hip arthroscopy, avascular necrosis and previous hip surgery were excluded. Ten patients refused to participate leaving 112 in the study. There were 62 women and 50 men. The mean age of the patients was 40.6 yrs (95% confidence interval (CI) 37.7 to 43.5). At arthroscopy, 23 patients underwent osteoplasty only for cam impingement, three underwent rim trimming only for pincer impingement, and 86 underwent both procedures for mixed-type impingement. The mean follow-up was 2.3 years (2.0 to 2.9). The mean modified Harris hip score (HHS) improved from 58 to 84 (mean difference = 24 (95% CI 19 to 28)) and the median patient satisfaction was 9 (1 to 10). Ten patients underwent total hip replacement at a mean of 16 months (8 to 26) after arthroscopy. The predictors of a better outcome were the pre-operative modified HHS (p = 0.018), joint space narrowing >or= 2 mm (p = 0.005), and repair of labral pathology instead of debridement (p = 0.032). Hip arthroscopy for femoroacetabular impingement, accompanied by suitable rehabilitation, gives a good short-term outcome and high patient satisfaction.

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An F4-derived F6 recombinant inbred line population (n = 148) of a cross between the durable stripe (yellow) rust (caused by Puccinia striiformis) and leaf (brown) rust (caused by Puccinia triticina) resistant cultivar, Triticum aestivum 'Cook', and susceptible genotype Avocet-YrA was phenotyped at several locations in Canada and Mexico under artificial epidemics of leaf or stripe rusts and genotyped using amplified fragment length polymorphism (AFLP) and microsatellite markers. Durable adult plant resistance to stripe and leaf rusts in 'Cook' is inherited quantitatively and was based on the additive interaction of linked and (or) pleiotropic slow-rusting genes Lr34 and Yr18 and the temperature-sensitive stripe rust resistance gene, YrCK, with additional genetic factors. Identified QTLs accounted for 18% to 31% of the phenotypic variation in leaf and stripe rust reactions, respectively. In accordance with the high phenotypic associations between leaf and stripe rust resistance, some of the identified QTLs appeared to be linked and (or) pleiotropic for both rusts across tests. Although a QTL was identified on chromosome 7D with significant effects on both rusts at some testing locations, it was not possible to refine the location of Lr34 or Yr18 because of the scarcity of markers in this region. The temperature-sensitive stripe rust resistance response, conditioned by the YrCK gene, significantly contributed to overall resistance to both rusts, indicating that this gene also had pleiotropic effects.

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OBJECTIVE: To assess predictors of chronic lung disease (CLD), in infants requiring nasal continuous positive airway pressure (CPAP) support in the first 4 weeks of life. METHODS: A retrospective case note audit of infants of birthweight 1250 g or less was undertaken. RESULTS: Of 290 infants identified, 50% were initially treated with ventilation, 41% with CPAP, 4% required no support, and 5% had care withdrawn. Of infants initially treated with CPAP, 23% subsequently required ventilation. Overall mortality was 19%, with a further 21% of infants developing CLD. For infants requiring CPAP support, requirement for supplementary oxygen at between 10 and 21 days predicted increased risk of CLD, and receiver operating characteristic curves suggest requirement for supplementary oxygen at 14 days to be the most reliable cut-off (area under curve = 0.72). Positive predictive values for future CLD or death for FiO2 .25, .30 and .40 while on CPAP at 14 days were 0.56, 0.61 and 0.76, respectively. CONCLUSIONS: CLD remains prevalent in very low birthweight infants in the CPAP era. Oxygen requirement at 14 days is the strongest predictor of CLD. Infants requiring 30% oxygen or more while on CPAP at 14 days have a 60% risk of subsequent CLD or death.

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OBJECTIVE: To show that in children with moderately severe cystic fibrosis lung disease: (i). inspiratory flow may be reduced; and (ii). peak inspiratory flow may be predicted from height, expiratory flow analysis or body mass index. METHODS: All children attending the Royal Children's Hospital, Melbourne, between May and July, 2001 who had cystic fibrosis, were aged > 5 years, were able to perform spirometry reproducibly and who had a forced expiratory volume in 1 s < 60% predicted were prospectively enrolled. Height, weight, peak inspiratory flow, forced expiratory volume in 1 s and forced vital capacity were recorded. Linear regression analysis was performed. RESULTS: The age range was 9.4-19.9 years. Sixteen boys and 11 girls were studied. All children had a peak inspiratory flow > 0.5 L/s. There was a significant relationship between peak inspiratory flow and forced vital capacity (R2 = 0.50) especially in boys (R2 = 0.65). In boys, peak inspiratory flow was significantly related to forced expiratory volume in 1 s (R2 = 0.47). There was no relationship between peak inspiratory flow and predicted values of expiratory flow, age, height, weight or body mass index. Logistic regression was used to predict the probability that peak inspiratory flow was < 2.0 L/s for a given forced vital capacity. If the forced vital capacity is > 2.5 L, peak inspiratory flow is likely to be > 2.0 L/s. CONCLUSIONS: In children with significant cystic fibrosis lung disease, peak inspiratory flow is likely to be > 0.5 L/s, which is required to activate dry powder inhalers. If the forced vital capacity is < 2.5 L, the peak inspiratory flow may be < 2.0 L/s, and a metered dose inhaler and spacer should be considered. Further studies that investigate the relationship between expiratory flow and peak inspiratory flow against an internal resistance are needed.

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Inheritance of adult-plant resistance to leaf rust, caused by Puccinia triticina, was studied in the progeny of a one-way diallel cross involving five CIMMYT-derived adult-plant resistant wheat (Triticum aestivum) genotypes and a susceptible wheat 'Avocet-YrA'. F1 progenies, F2 populations, F2-derived F3, and F4-derived F5 lines were field evaluated under artificial epidemics with leaf rust race MCJ/SP. Adult-plant resistance to leaf rust was incompletely dominant in crosses with the susceptible parent and was found to be controlled by additive interactions of Lr34 with at least two to three additional genes. Transgressive segregation giving rise to plants or lines with higher and lower levels of resistance than the parents was observed in all F2 and F5 derivatives of the resistant-parent intercrosses and suggested that, apart from Lr34, some of the other additive genes were nonallelic. Although specific combining ability was significant in some generations, general combining ability was found to be the major component of variation. Among generations, the estimates of the narrow-sense heritability of adult-plant resistance to leaf rust ranged from 0.67 to 0.97.

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Forty-four barley accessions and commercial cultivars with different levels of resistance to scald caused by Rhynchosporium secalis were evaluated for scald reaction from 1997 to 1999 at various sites in Alberta. The accessions Hudson, Atlas, Atlas 46, Atlas 68, Abyssinian, and Kitchin that have the major resistance genes were resistant to pathotypes of R. secalis at all sites. Although scald levels were low for these accessions, they were significantly different among years. Pathotypes of R. secalis and environmental conditions affected diseases levels on 32 commercial cultivars, resulting in significantly different scald reactions among sites and seasons. Resistance in commercial cultivars, AC Stacy, Kasota, and Seebe, held up at most sites with the majority of cultivars being intermediate to moderately susceptible. Cultivars that were previously considered resistant were intermediate in reaction and became increasingly susceptible at some sites from 1997 to 1999. Pathogen virulence was more diverse at the sites where the cultivars became increasingly susceptible compared with sites where the same cultivars were resistant. Scald reactions of the commercial cultivars depended on location, which reflected the presence of different pathotypes, as well as variation in environmental conditions. Consequently, scald management via cultivar choice will be dependent on location.

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The case of a 56 year old man who suffered a spontaneous intracerebral haemorrhage after regular self medication with the herbal preparation, Ginkgo biloba leaf extract is described, and the possible association is discussed.

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The molecular biology of flowering has been most extensively studied in the quantitative long-day plant Arabidopsis thaliana. The Arabidopsis LUMINIDEPENDENS (LD) gene encodes a potential transcriptional regulator that acts as a positive effector of flowering, at least in part through suppression of the floral inhibitor gene FLC. As an initial step to explore the conservation of the molecular mechanisms of flowering among plants of various flowering habits, and to further investigate the molecular action(s) of LD, we have identified a gene from maize (Zea mays) that is closely related to Arabidopsis LD. The major product of this gene, which we have designated ZmLD for Zea mays LUMINIDEPENDENS, contains four conserved regions that may constitute functionally important components of the LD proteins. One of these regions closely resembles the canonical homeodomain. The ZmLD gene exists as a single copy in the maize genome, and generates a major ca. 4.0 kb transcript, and a minor ca. 2.6 kb transcript that results from alternative transcriptional termination. The 4.0 kb ZmLD alpha transcript accumulated to highest levels in proliferative tissues, including the shoot apex and developing inflorescences. Expression of ZnLD alpha under control of the Arabidopsis LD promoter in transgenic Arabidopsis caused developmental defects similar to those conferred by loss-of-function mutations in a class of genes involved in maintaining the proliferative nature of the shoot, inflorescence, and floral meristems. These effects were not influenced markedly by the activities of the Arabidopsis LD or FLC genes. We consider the implications for the conservation of LD function between maize and Arabidopsis.

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Smooth muscle (SM) specific alternate splicing of a number of genes is a late marker of the differentiated vascular smooth muscle cell (VSMC) phenotype and is one of the first differentiation characteristics to be lost during de-differentiation and in disease. An understanding of how this aspect of VSMC phenotype is regulated may provide insights into the earliest events of the atherosclerotic process. TGF-beta1 is a potent regulator of VSMC differentiation and can induce expression of SM-specific contractile proteins in both pluripotent stem cells and de-differentiated VSMCs. The purpose of this study was to test the hypothesis that members of the TGFbeta-superfamily can also effect SM-specific alternative splicing. Firstly, we established that SM-specific splicing of alpha-tropomyosin, vinculin and SM-myosin heavy chain (MHC) increases during rat fetal/neonatal development and is decreased in VSMCs following balloon-induced carotid injury in the rat. Treatment of cultured rat VSMCs with TGFbeta-superfamily members resulted in a significant reduction in the ratio of SM to non-muscle (NM) alpha-tropomyosin, but did not effect SM-specific alternative splicing of vinculin or SM-MHC. Treatment of pluripotent C3H10T1/2 cells with TGF-beta1, which increased SM differentiation marker expression, did not increase SM-specific alpha-tropomyosin splicing. Taken together, these results demonstrate differential regulation of SM-specific alternative splicing and indicate that although TGF-beta1 promotes VSMC differentiation marker expression, TGF-beta1 cannot act as the sole trigger of VSMC differentiation.

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