126 research outputs found
Membrane insertion and secretion of the Engrailed-2 (EN2) transcription factor by prostate cancer cells may induce antiviral activity in the stroma
YesEngrailed-2 (EN2) is a homeodomain-containing transcription factor that has roles in boundary formation and neural guidance in early development, but which is also expressed in a range of cancers. In addition to transcriptional regulation, it is secreted by cells and taken up by others through a mechanism that is yet to be fully elucidated. In this study, the distribution of EN2 protein in cells was evaluated using immunofluorescence with a set of antibodies raised against overlapping epitopes across the protein, and through the use of an EN2-GFP construct. MX2 expression in primary prostate tumors was evaluated using immunohistochemistry. We showed that EN2 protein is present in the cell membrane and within microvesicles that can be secreted from the cell and taken up by others. When taken up by normal cells from the stroma EN2 induces the expression of MX2 (MxB), a protein that has a key role in the innate immune response to viruses. Our findings indicate that EN2 secretion by tumors may be a means of preventing viral-mediated immune invasion of tissue immediately adjacent to the tumor.The Ringrose Family Trust supported this study through a studentship awarded to N.P
Estimation of linear quadratic (LQ) model parameter alpha/beta (α/β) and biologically effective dose (BED) for acute normal tissue reactions in head and neck malignancies
Purpose: Linear-Quadratic (LQ) model has been widely used for describing radiobiological effectiveness of various fractionation schedules on tumour as well as normal tissues. This study estimates α/β for acute normal tissue reactions using Fe-plot method.Methods: 50 cases of locally advanced head and neck squamous cell carcinoma (stage III and IV) treated with external beam radiotherapy were included in this study. Patients were randomly distributed into Hyper-fractionation (HF) arm (1.2 Gy/fraction, twice daily, 6 hours apart) and conventional fractionation (CF) arm (2 Gy/fraction, once daily) with 25 cases in each arm. α/β and BED were calculated for acute normal tissue reactions using Fe-plot method.Results: In our study, the estimated values of α/β for RTOG (Radiation Therapy Oncology Group) grade 1, 2 and 3 skin reactions were 11.2 Gy, 10.1 Gy and 9 Gy respectively. Estimated values of α/β for RTOG grade 1, 2 and 3 mucosal reactions were 9.7 Gy, 8.0 Gy and 9.1 Gy respectively. For Hyper-fractionation arm, calculated BED values for grade 1, 2 and 3 skin reactions were 54.45 Gy11.239, 66.90 Gy10.114 and 73.43Gy9.001 respectively and for grade 1, 2 and 3 mucosal reactions were 33.5 Gy9.797, 57.8 Gy8.011 and 70.8 Gy9.106 respectively. For conventional fractionation arm, calculated BED values for grade 1, 2 and 3 skin reactions were 54.09 Gy11.239, 66.88 Gy10.114 and 73.33 Gy9.001 respectively and for grade 1, 2 and 3 mucosal reactions were 33.52 Gy9.797, 57.68 Gy8.011 and 70.73 Gy9.106 respectively.Conclusion: LQ model and the concept of BED provide an excellent tool to compare different fractionation schedules in radiotherapy. The estimated values of α/β for acute reacting normal tissues are in good agreement with the available literature
Use of industrial wastes as sustainable nutrient sources for bacterial cellulose (BC) production: mechanism, advances, and future perspectives
A novel nanomaterial, bacterial cellulose (BC), has become noteworthy recently due to its better physicochemical properties and biodegradability, which are desirable for various applications. Since cost is a significant limitation in the production of cellulose, current efforts are focused on the use of industrial waste as a cost-effective substrate for the synthesis of BC or microbial cellulose. The utilization of industrial wastes and byproduct streams as fermentation media could improve the cost-competitiveness of BC production. This paper examines the feasibility of using typical wastes generated by industry sectors as sources of nutrients (carbon and nitrogen) for the commercial- scale production of BC. Numerous preliminary findings in the literature data have revealed the potential to yield a high concentration of BC from various industrial wastes. These findings indicated the need to optimize culture conditions, aiming for improved large-scale production of BC from waste streams
Validity and reliability of subjective methods to assess sedentary behaviour in adults: a systematic review and meta-analysis.
BACKGROUND: Subjective measures of sedentary behaviour (SB) (i.e. questionnaires and diaries/logs) are widely implemented, and can be useful for capturing type and context of SBs. However, little is known about comparative validity and reliability. The aim of this systematic review and meta-analysis was to: 1) identify subjective methods to assess overall, domain- and behaviour-specific SB, and 2) examine the validity and reliability of these methods. METHODS: The databases MEDLINE, EMBASE and SPORTDiscus were searched up to March 2020. Inclusion criteria were: 1) assessment of SB, 2) evaluation of subjective measurement tools, 3) being performed in healthy adults, 4) manuscript written in English, and 5) paper was peer-reviewed. Data of validity and/or reliability measurements was extracted from included studies and a meta-analysis using random effects was performed to assess the pooled correlation coefficients of the validity. RESULTS: The systematic search resulted in 2423 hits. After excluding duplicates and screening on title and abstract, 82 studies were included with 75 self-reported measurement tools. There was wide variability in the measurement properties and quality of the studies. The criterion validity varied between poor-to-excellent (correlation coefficient [R] range - 0.01- 0.90) with logs/diaries (R = 0.63 [95%CI 0.48-0.78]) showing higher criterion validity compared to questionnaires (R = 0.35 [95%CI 0.32-0.39]). Furthermore, correlation coefficients of single- and multiple-item questionnaires were comparable (1-item R = 0.34; 2-to-9-items R = 0.35; ≥10-items R = 0.37). The reliability of SB measures was moderate-to-good, with the quality of these studies being mostly fair-to-good. CONCLUSION: Logs and diaries are recommended to validly and reliably assess self-reported SB. However, due to time and resources constraints, 1-item questionnaires may be preferred to subjectively assess SB in large-scale observations when showing similar validity and reliability compared to longer questionnaires. REGISTRATION NUMBER: CRD42018105994
Chemical treatment of the intra-canal dentin surface: a new approach to modify dentin hydrophobicity
OBJECTIVE: This study evaluated the hydrophobicity of dentin surfaces that were modified through chemical silanization with octadecyltrichlorosilane (OTS). MATERIAL AND METHODS: An in vitro experimental study was performed using 40 human permanent incisors that were divided into the following two groups: non-silanized and silanized. The specimens were pretreated and chemically modified with OTS. After the chemical modification, the dentin hydrophobicity was examined using a water contact angle measurement (WCA). The effectiveness of the modification of hydrophobicity was verified by the fluid permeability test (FPT). RESULTS AND CONCLUSIONS: Statistically significant differences were found in the values of WCA and FPT between the two groups. After silanization, the hydrophobic intraradicular dentin surface exhibited in vitro properties that limit fluid penetration into the sealed root canal. This chemical treatment is a new approach for improving the sealing of the root canal system
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Daily steps and all-cause mortality: a meta-analysis of 15 international cohorts.
BACKGROUND: Although 10 000 steps per day is widely promoted to have health benefits, there is little evidence to support this recommendation. We aimed to determine the association between number of steps per day and stepping rate with all-cause mortality. METHODS: In this meta-analysis, we identified studies investigating the effect of daily step count on all-cause mortality in adults (aged ≥18 years), via a previously published systematic review and expert knowledge of the field. We asked participating study investigators to process their participant-level data following a standardised protocol. The primary outcome was all-cause mortality collected from death certificates and country registries. We analysed the dose-response association of steps per day and stepping rate with all-cause mortality. We did Cox proportional hazards regression analyses using study-specific quartiles of steps per day and calculated hazard ratios (HRs) with inverse-variance weighted random effects models. FINDINGS: We identified 15 studies, of which seven were published and eight were unpublished, with study start dates between 1999 and 2018. The total sample included 47 471 adults, among whom there were 3013 deaths (10·1 per 1000 participant-years) over a median follow-up of 7·1 years ([IQR 4·3-9·9]; total sum of follow-up across studies was 297 837 person-years). Quartile median steps per day were 3553 for quartile 1, 5801 for quartile 2, 7842 for quartile 3, and 10 901 for quartile 4. Compared with the lowest quartile, the adjusted HR for all-cause mortality was 0·60 (95% CI 0·51-0·71) for quartile 2, 0·55 (0·49-0·62) for quartile 3, and 0·47 (0·39-0·57) for quartile 4. Restricted cubic splines showed progressively decreasing risk of mortality among adults aged 60 years and older with increasing number of steps per day until 6000-8000 steps per day and among adults younger than 60 years until 8000-10 000 steps per day. Adjusting for number of steps per day, comparing quartile 1 with quartile 4, the association between higher stepping rates and mortality was attenuated but remained significant for a peak of 30 min (HR 0·67 [95% CI 0·56-0·83]) and a peak of 60 min (0·67 [0·50-0·90]), but not significant for time (min per day) spent walking at 40 steps per min or faster (1·12 [0·96-1·32]) and 100 steps per min or faster (0·86 [0·58-1·28]). INTERPRETATION: Taking more steps per day was associated with a progressively lower risk of all-cause mortality, up to a level that varied by age. The findings from this meta-analysis can be used to inform step guidelines for public health promotion of physical activity. FUNDING: US Centers for Disease Control and Prevention
Physical activity, sedentary time and breast cancer risk: a Mendelian randomisation study
Objectives: Physical inactivity and sedentary behaviour are associated with higher breast cancer risk in observational studies, but ascribing causality is difficult. Mendelian randomisation (MR) assesses causality by simulating randomised trial groups using genotype. We assessed whether lifelong physical activity or sedentary time, assessed using genotype, may be causally associated with breast cancer risk overall, pre/post-menopause, and by case-groups defined by tumour characteristics.
Methods: We performed two-sample inverse-variance-weighted MR using individual-level Breast Cancer Association Consortium case-control data from 130 957 European-ancestry women (69 838 invasive cases), and published UK Biobank data (n=91 105–377 234). Genetic instruments were single nucleotide polymorphisms (SNPs) associated in UK Biobank with wrist-worn accelerometer-measured overall physical activity (nsnps=5) or sedentary time (nsnps=6), or accelerometer-measured (nsnps=1) or self-reported (nsnps=5) vigorous physical activity.
Results: Greater genetically-predicted overall activity was associated with lower breast cancer overall risk (OR=0.59; 95% confidence interval (CI) 0.42 to 0.83 per-standard deviation (SD;~8 milligravities acceleration)) and for most case-groups. Genetically-predicted vigorous activity was associated with lower risk of pre/perimenopausal breast cancer (OR=0.62; 95% CI 0.45 to 0.87,≥3 vs. 0 self-reported days/week), with consistent estimates for most case-groups. Greater genetically-predicted sedentary time was associated with higher hormone-receptor-negative tumour risk (OR=1.77; 95% CI 1.07 to 2.92 per-SD (~7% time spent sedentary)), with elevated estimates for most case-groups. Results were robust to sensitivity analyses examining pleiotropy (including weighted-median-MR, MR-Egger).
Conclusion: Our study provides strong evidence that greater overall physical activity, greater vigorous activity, and lower sedentary time are likely to reduce breast cancer risk. More widespread adoption of active lifestyles may reduce the burden from the most common cancer in women
A genome-wide gene-environment interaction study of breast cancer risk for women of European ancestry
Background
Genome-wide studies of gene–environment interactions (G×E) may identify variants associated with disease risk in conjunction with lifestyle/environmental exposures. We conducted a genome-wide G×E analysis of ~ 7.6 million common variants and seven lifestyle/environmental risk factors for breast cancer risk overall and for estrogen receptor positive (ER +) breast cancer.
Methods
Analyses were conducted using 72,285 breast cancer cases and 80,354 controls of European ancestry from the Breast Cancer Association Consortium. Gene–environment interactions were evaluated using standard unconditional logistic regression models and likelihood ratio tests for breast cancer risk overall and for ER + breast cancer. Bayesian False Discovery Probability was employed to assess the noteworthiness of each SNP-risk factor pairs.
Results
Assuming a 1 × 10–5 prior probability of a true association for each SNP-risk factor pairs and a Bayesian False Discovery Probability < 15%, we identified two independent SNP-risk factor pairs: rs80018847(9p13)-LINGO2 and adult height in association with overall breast cancer risk (ORint = 0.94, 95% CI 0.92–0.96), and rs4770552(13q12)-SPATA13 and age at menarche for ER + breast cancer risk (ORint = 0.91, 95% CI 0.88–0.94).
Conclusions
Overall, the contribution of G×E interactions to the heritability of breast cancer is very small. At the population level, multiplicative G×E interactions do not make an important contribution to risk prediction in breast cancer
Antioxidant potential of n-butanol fraction from extract<i style=""> </i>of<i style=""> Jasminum mesnyi</i> Hance leaves
39-43Methanolic extract of Jasminum mesnyi Hance leaves having antidiabetic activity was
subjected to fractionation to obtain antioxidant and antihyperglycemic rich
fraction. Different concentrations of ethyl acetate and n-butanol fractions
were subjected to antioxidant assay by DPPH method, nitric oxide scavenging
activity and reducing power assay. The fractions showed dose dependent free
radical scavenging property in all the models. IC50 values for ethyl
acetate and n-butanol fractions were 153.45±6.65 and 6.22±0.25 g/ml, respectively, as compared to L-ascorbic acid and rutin (as
standards; IC50 values 6.54±0.24 and 5.43±0.21 g/ml, respectively) in DPPH model. In nitric oxide
scavenging activity, IC50 values were 141.54±9.95 g/ml, 35.12±1.58 g/ml, 21.06±0.95 g/ml and 29.93±0.32
g/ml for ethyl acetate, n-butanol fractions,
L-ascorbic acid and rutin, respectively. n-Butanol fraction showed a good
reducing potential and better free radical scavenging activity as compared to
ethyl acetate fraction. Potent antioxidant n-butanol fraction showed better
oral glucose tolerance test (antihyperglycemic) at par with metformin (standard
drug). n-Butanol fraction contained secoiridoid glycosides which might be
responsible for both antioxidant and antihyperglycemic activity
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