Mach's Principle and Model for a Broken Symmetric Theory of Gravity

We investigate spontaneous symmetry breaking in a conformally invariant gravitational model. In particular, we use a conformally invariant scalar tensor theory as the vacuum sector of a gravitational model to examine the idea that gravitational coupling may be the result of a spontaneous symmetry breaking. In this model matter is taken to be coupled with a metric which is different but conformally related to the metric appearing explicitly in the vacuum sector. We show that after the spontaneous symmetry breaking the resulting theory is consistent with Mach's principle in the sense that inertial masses of particles have variable configurations in a cosmological context. Moreover, our analysis allows to construct a mechanism in which the resulting large vacuum energy density relaxes during evolution of the universe.Comment: 9 pages, no figure

[Epidemiology of oral cavity cancers in France].

INTRODUCTION: We had for objective to describe the updated epidemiology of oral cancers in France. MATERIAL AND METHODS: Estimates made from data collected from various French cancer institutions. The distribution by topography, histology, regions, mean age, and specific incidence rates were calculated from the collected data. The survival data was taken from the Francim network studies. RESULTS: Approximately 7000 oral cavity cancers were diagnosed in France in 2005. In 2007, 1746 people died of that cancer. Standardized (world population) incidence rates are respectively, in men and women, 12.3 and 3.0 cases per 100,000 person-years. These cancers have significantly decreased in men: the standardized incidence rate decreased by 43.2% between 1980 and 2005. Among women, the trend is reversed with an increased incidence of 51.7% over the same period. CONCLUSION: In France, the incidence of oral cavity cancers has been strongly decreasing in men and strongly increasing in women. This trend should be compared to the frequency of the main risk factors: alcohol and tobacco

Release of Soluble Receptors for Tumor Necrosis Factor in Clinical Sepsis and Experimental Endotoxemia

To assess the role of tumor necrosis factor (TNF) in the appearance of soluble TNF receptors (sTNFRs), 20 consecutive patients with a clinical diagnosis of sepsis were studied as were 7 chimpanzees after administration of endotoxin (4 ng/kg) with or without pentoxifylline. The patients had markedly elevated serum levels of sTNFR-p55 and sTNFR-p75 compared with healthy controls (P < .0001 for both receptors). The levels of both soluble receptors correlated with simultaneously measured immunoreactive TNF concentrations (p55: r = .63, P < .01; p75: r = .69, P < .001). In the chimpanzees, endotoxin induced subsequent rises in the serum concentrations ofTNF and sTNFRs. Although pentoxifylline reduced the TNF response to intravenous endotoxin to 20% (P < .05), the appearance of sTNFRs was only moderately inhibited (sTNFR-p55 to 79% on average, P < .05; sTNFR-p75 to 77%, P = .12). These results indicate that TNF either does not play an important role in the appearance of sTNFRs in systemic infection or that a small amount ofTNF remaining in the circulation after some bacterial challenges is sufficient to preserve the secretion of its soluble receptor

Estimates of genetic parameters and genetic gains for growth traits of two Eucalyptus urophylla populations in Zululand, South Africa

In South Africa, Eucalyptus urophylla is an important species due to its disease tolerance to fungal diseases like Crysoporthe austroafricana and the Coniothyrium sp. cankers. It is mainly planted as a parental species in a hybrid combination with E. grandis. Generally, the E. grandis x E. urophylla hybrid has better disease tolerance and higher wood density than pure E. grandis. The current strategy is to maintain large breeding populations of both parental species in order to provide improved elite selections for hybrid crosses on a regular basis. With this in mind, two E. urophylla populations, consisting of five provenance/progeny trials, were established in the subtropical region of Zululand. The aims of this study were firstly to determine the magnitude of genotype by environment interaction of E. urophylla in Zululand; secondly to estimate genetic parameter and correlations for DBH, height and volume; and lastly to identify selections to advance the current breeding population as well as to hybridise with E. grandis. Results indicated that genotype by environment interaction effects would be practically negligible for growth in Zululand and a single breeding population will therefore be appropriate. In general, all growth traits were under low to moderate genetic control, with narrow sense heritabilities ranging between 0.14 and 0.48 for volume. The genetic correlations between growth traits were high (0.98 and 0.99 for DBH-volume). This is an indication that DBH is a sufficient growth measure to use in E. urophylla breeding programmes. BLUP estimates indicated that a selection scenario of 200 individuals will generate genetic gains of 44.7% over the population mean. The estimated gains for the top 50 individuals that could potentially be used as hybrid parents to cross with E. grandis was 59.8% over the population mean.Funding was provided by Mondi training department.http://www.tandfonline.com/loi/tsfs202017-08-31hb2016Plant Production and Soil Scienc

Genetic parameters of interspecific hybrids of Eucalyptus grandis and E.urophylla seedings and cuttings

The current E. grandis x E. urophylla hybrid breeding strategy of South Africa’s Forestry Industry is to maintain large breeding populations of both parental species in which parents are selected based on their general combining ability (GCA) estimates or predicted individual tree breeding values and are used for interspecific hybrid crosses. The hybrid material is first screened in seedling progeny trials after which superior individuals are selected and tested as clones. Although this strategy has delivered superior clones for commercial production in South Africa, it is a time consuming strategy to follow and more cost effective strategies are being investigated. In order to review the current hybrid breeding strategy, information on the genetic control of the traits of interest is needed for E. grandis x E. urophylla seedling and clonal populations. The main objectives of this study were therefore to firstly estimate genetic parameters for E. grandis x E. urophylla hybrid seedling and clonal populations; secondly to investigate the correlation between E. grandis and E. urophylla parental (GCA) or individual breeding values and their general hybridising ability (GHA); and lastly to determine the correlation between E. grandis x E. urophylla hybrid seedling ortets and their ramets. Results of our study indicated that non-additive genetic variation explained the majority of the total genetic variation in E. grandis x E. urophylla seedling and clonal populations. Due to the pre-eminence of non-additive variance, the pure-hybrid correlations were weak, especially for clonal populations. It would therefore seem that GCA or predicted individual breeding values are not good predictors of GHA for growth performance in the observed populations. Our study also indicated a weak coefficient of correlation between the growth performance of seedling ortets and their ramets. These results suggest that: firstly a hybrid breeding strategy to capture non-additive genetic variation should be adopted; and secondly that the first phase of screening E. grandis x E. urophylla hybrid material as seedlings should be revisited. Genetic Parameters of Interspecific Hybrids of Eucalyptus grandis and E. urophylla Seedlings and Cuttings.Mondi training departmenthttp://www.sauerlaender-verlag.com/zeitschriften/silvae-geneticaPlant Production and Soil Scienc

Adeno-associated virus mediated delivery of Tregitope 167 ameliorates experimental colitis

Aim: To explore the anti-inflammatory potential of adeno-associated virus-mediated delivery of Tregitope 167 in an experimental colitis model. Methods: The trinitrobenzene sulfonate (TNBS) model of induced colitis was used in Balb/c mice. Subsequently after intravenous adeno-associated virus-mediated regulatory T-cell epitopes (Tregitope) delivery, acute colitis was initiated by intra-rectal administration of 1.5 mg TNBS in 40% ethanol followed by a second treatment with TNBS (0.75 mg in 20% ethanol) 8 d later. Control groups included mice not treated with TNBS (healthy control group) and mice treated by TNBS only (diseased group). At the time of sacrifice colon weight, the disease activity index and histology damage score were determined. Immunohistochemical staining of the colonic tissues was performed to asses the cellular infiltrate and the presence of transcription factor forkhead Box-P3 (Foxp3). Thymus, mesenteric lymph nodes, liver and spleen tissue were collected and the corresponding lymphocyte populations were further assessed by flow cytometry analysis for the expression of CD4+ T cell and regulatory T cell associated markers. Results: The Tregitope 167 treated mice gained an average of 4% over their initial body weight at the time of sacrifice. In contrast, the mice treated with TNBS alone (no Tregitope) developed colitis, and lost 4% of their initial body weight at the time of sacrifice (P \u3c 0.01). The body weight increase that had been observed in the mice pre-treated with Tregitope 167 was substantiated by a lower disease activity index and a decreased colon weight as compared to the diseased control group (P \u3c 0.01 and P \u3c 0.001, respectively). Immunohistochemical staining of the colonic tissues for CD4+ showed that inflammatory cell infiltrates were present in TNBS treated mice with or without administration with tregitope 167 and that these cellular infiltrates consisted mainly of CD4+ cells. For both TNBS treated groups CD4+ T cell infiltrates were observed in the sub-epithelial layer and the lamina propria. CD4+ T cell infiltrates were also present in the muscularis mucosa layer of the diseased control mice, but were absent in the Tregitope 167 treated group. Numerous Foxp3 positive cells were detected in the lamina propria and sub-epithelium of the colon sections from mice treated with Tregitope 167. Furthermore, the Foxp3 and glycoprotein A repetitions predominant markers were significantly increased in the CD4+ T lymphocyte population in the thymus of the mice pre-treated with adeno-associated virus serotype 5 (cytomegalovirus promoter-Tregitope 167), as cytomegalovirus promoter compared to lymphocyte populations in the thymus of diseased and the healthy control mice (P \u3c 0.05 and P \u3c 0.001, respectively). Conclusion: This study identifies adeno-associated virus-mediated delivery of regulatory T-cell epitope 167 as a novel anti-inflammatory approach with the capacity to decrease intestinal inflammation and induce long-term remission in inflammatory bowel disease

Circulating Fibrocytes Prepare the Lung for Cancer Metastasis by Recruiting Ly-6C+ Monocytes Via CCL2

Fibrocytes are circulating, hematopoietic cells that express CD45 and Col1a1. They contribute to wound healing and several fibrosing disorders by mechanisms that are poorly understood. In this report, we demonstrate that fibrocytes predispose the lung to B16-F10 metastasis by recruiting Ly-6C+ monocytes. To do so, we isolated fibrocytes expressing CD45, CD11b, CD13, and Col1a1 from the lungs of wild type (WT) and Ccr5−/− mice. WT but not Ccr5−/− fibrocytes increased the number of metastatic foci when injected into Ccr5−/− mice (73 ± 2 versus 32 ± 5; p < 0.001). This process was MMP9 dependent. Injection of WT enhanced GFP+ fibrocytes also increased the number of Gr-1Int, CD11b+, and enhanced GFP− monocytes. Like premetastatic-niche monocytes, these recruited cells expressed Ly-6C, CD117, and CD45. The transfer of these cells into Ccr5−/− mice enhanced metastasis (90 ± 8 foci) compared with B cells (27 ± 2), immature dendritic cells (31 ± 6), or alveolar macrophages (28 ± 3; p < 0.05). WT and Ccl2−/− fibrocytes also stimulated Ccl2 expression in the lung by 2.07 ± 0.05- and 2.78 ± 0.36-fold compared with Ccr5−/− fibrocytes (1.0 ± 0.06; p < 0.05). Furthermore, WT fibrocytes did not increase Ly-6C+ monocytes in Ccr2−/− mice and did not promote metastasis in either Ccr2−/− or Ccl2−/− mice. These data support our hypothesis that fibrocytes contribute to premetastatic conditioning by recruiting Ly-6C+ monocytes in a chemokine-dependent process. This work links metastatic risk to conditions that mobilize fibrocytes, such as inflammation and wound repair

C-C Chemokine Receptor 5 on Pulmonary Mesenchymal Cells Promotes Experimental Metastasis via the Induction of Erythroid Differentiation Regulator 1

C-C Chemokine receptor five knockout (Ccr5-/-) mice develop fewer experimental pulmonary metastases than wild type (WT) mice. This phenomenon was explored by applying gene-expression profiling to the lungs of mice with these metastases. Consequently, Erythroid Differentiation Regulator 1 (Erdr1) was identified as upregulated in the WT mice. Though commonly associated with bone marrow stroma, Erdr1 was differentially expressed in WT pulmonary mesenchymal cells (PMCs) and murine embryonic fibroblasts (MEFs). Moreover, the Ccr5 ligand Ccl4 increased its expression by 3.36 ± 0.14 fold. Ccr5 signaling was dependent on the Map2k but not the Pi3k pathway since treatment with U0126 inhibited upregulation of Erdr1 but treatment with LY294002 increased the expression by 3.44 ± 0.92 fold (p < 0.05). Erdr1's effect on B16-F10 melanoma metastasis was verified by the adoptive transfer of WT MEFs into Ccr5-/- mice. In this model, MEFs that had been transduced with Erdr1 shRNA lowered metastasis by 33% compared to control transduced MEFs. The relevance of ERDR1 on human disease was assessed by co-culturing chronic lymphocytic leukemia (CLL) cells with M2-10B4 stromal cells that had been transfected with shRNA or control plasmids. After 96 hours of co-culture, the cell counts were higher with control cell lines compared with Erdr1 knockdown lines (OR 1.88 ± 0.27, 2.52 ± 0.66 respectively). This increase was associated with a decrease in apoptotic cells (OR 0.69 ± 0.18, 0.58 ± 0.12 respectively)

The start of sexual health curriculum development and evaluation at Stellenbosch University

Background: Stellenbosch University’s (SU) Faculty of Medicine and Health Sciences (FMHS), developed a sexual health course to be integrated throughout the revised medical curriculum. Aim: To use the Sexual Health Education for Professionals Scale (SHEPS) to gather baseline and future follow-up data to inform curriculum development and evaluation. Setting: The first-year medical students (N = 289) of the FMHS SU. Methods: The SHEPS was answered before the start of the sexual health course. The knowledge, communication and attitude sections were answered with a Likert-type scale. Students had to describe their perceived confidence in their knowledge and communication skills to care for patients within specific sexuality-related clinical scenarios. The attitude section measured the students’ level of agreement or disagreement on sexuality-related opinion statements. Results: The response rate was 97%. Most students were female, and 55% of the class were first taught about sexuality in the age group 13–18 years. The students had more confidence in their communication skills than knowledge before any tertiary training. The attitude section revealed a binomial distribution, ranging from acceptance to a more restrictive attitude towards sexual behaviour. Conclusion: It is the first time the SHEPS has been used in a South African context. The results provide novel information about the range of perceived sexual health knowledge, skills and attitudes of first-year medical students before they start tertiary training. Contribution: Findings from this study will guide content development and evaluation of the sexual health course at the institution where the study was conducted, as well as allow for culture sensitive education