Introduction Tobacco, alcohol and illicit drug use contribute significantly to global rates of morbidity and mortality. Despite evidence suggesting interventions designed to increase adolescent ...resilience may represent a means of reducing adolescent substance use, and schools providing a key opportunity to implement such interventions, existing systematic reviews assessing the effectiveness of school-based interventions targeting adolescent substance use have not examined this potential. Methods and analysis The aim of the systematic review is to determine whether universal interventions focused on enhancing the resilience of adolescents are effective in reducing adolescent substance use. Eligible studies will: include participants 5–18 years of age; report tobacco use, alcohol consumption or illicit drug use as outcomes; and implement a school-based intervention designed to promote internal (eg, self-esteem) and external (eg, school connectedness) resilience factors. Eligible study designs include randomised controlled trials, cluster randomised controlled trials, staggered enrolment trials, stepped wedged trials, quasi-randomised trials, quasi-experimental trials, time series/interrupted time-series trials, preference trials, regression discontinuity trials and natural experiment studies with a parallel control group. A search strategy including criteria for participants, study design, outcome, setting and intervention will be implemented in various electronic databases and information sources. Two reviewers will independently screen studies to assess eligibility, as well as extract data from, and assess risk of bias of included studies. A third reviewer will resolve any discrepancies. Attempts will be made to quantify trial effects by meta-analysis. Binary outcomes will be pooled and effect size reported using ORs. For continuous data, effect size of trials will be reported using a mean difference where trial outcomes report the same outcome using a consistent measure, or standardised mean difference where trials report a comparable measure. Otherwise, trial outcomes will be described narratively. Dissemination Review findings will be disseminated via peer-reviewed journals and conferences.
Homologous recombination mediated by RAD51 recombinase helps eliminate chromosomal lesions, such as DNA double-strand breaks induced by radiation or arising from injured DNA replication forks. The ...tumor suppressors BRCA2 and PALB2 act together to deliver RAD51 to chromosomal lesions to initiate repair. Here we document a new function of PALB2: to enhance RAD51's ability to form the D loop. We show that PALB2 binds DNA and physically interacts with RAD51. Notably, although PALB2 alone stimulates D-loop formation, it has a cooperative effect with RAD51AP1, an enhancer of RAD51. This stimulation stems from the ability of PALB2 to function with RAD51 and RAD51AP1 to assemble the synaptic complex. Our results demonstrate the multifaceted role of PALB2 in chromosome damage repair. Because PALB2 mutations can cause cancer or Fanconi anemia, our findings shed light on the mechanism of tumor suppression in humans.
Earth is home to a remarkable diversity of plant forms and life histories, yet comparatively few essential trait combinations have proved evolutionarily viable in today's terrestrial biosphere. By ...analysing worldwide variation in six major traits critical to growth, survival and reproduction within the largest sample of vascular plant species ever compiled, we found that occupancy of six-dimensional trait space is strongly concentrated, indicating coordination and trade-offs. Three-quarters of trait variation is captured in a two-dimensional global spectrum of plant form and function. One major dimension within this plane reflects the size of whole plants and their parts; the other represents the leaf economics spectrum, which balances leaf construction costs against growth potential. The global plant trait spectrum provides a backdrop for elucidating constraints on evolution, for functionally qualifying species and ecosystems, and for improving models that predict future vegetation based on continuous variation in plant form and function.
Mapping red blood cells (RBCs) flow and oxygenation is of key importance for analyzing brain and tissue physiology. Current microscopy methods are limited either in sensitivity or in spatio-temporal ...resolution. In this work, we introduce a novel approach based on label-free third-order sum-frequency generation (TSFG) and third-harmonic generation (THG) contrasts. First, we propose a novel experimental scheme for color TSFG microscopy, which provides simultaneous measurements at several wavelengths encompassing the Soret absorption band of hemoglobin. We show that there is a strong three-photon (3P) resonance related to the Soret band of hemoglobin in THG and TSFG signals from zebrafish and human RBCs, and that this resonance is sensitive to RBC oxygenation state. We demonstrate that our color TSFG implementation enables specific detection of flowing RBCs in zebrafish embryos and is sensitive to RBC oxygenation dynamics with single-cell resolution and microsecond pixel times. Moreover, it can be implemented on a 3P microscope and provides label-free RBC-specific contrast at depths exceeding 600 µm in live adult zebrafish brain. Our results establish a new multiphoton contrast extending the palette of deep-tissue microscopy.
Predicting response to endocrine therapy and survival in oestrogen receptor positive breast cancer is a significant clinical challenge and novel prognostic biomarkers are needed. Long-range ...regulators of gene expression are emerging as promising biomarkers and therapeutic targets for human diseases, so we have explored the potential of distal enhancer elements of non-coding RNAs in the prognostication of breast cancer survival. HOTAIR is a long non-coding RNA that is overexpressed, promotes metastasis and is predictive of decreased survival. Here, we describe a long-range transcriptional enhancer of the HOTAIR gene that binds several hormone receptors and associated transcription factors, interacts with the HOTAIR promoter and augments transcription. This enhancer is dependent on Forkhead-Box transcription factors and functionally interacts with a novel alternate HOTAIR promoter. HOTAIR expression is negatively regulated by oestrogen, positively regulated by FOXA1 and FOXM1, and is inversely correlated with oestrogen receptor and directly correlated with FOXM1 in breast tumours. The combination of HOTAIR and FOXM1 enables greater discrimination of endocrine therapy responders and non-responders in patients with oestrogen receptor positive breast cancer. Consistent with this, HOTAIR expression is increased in cell-line models of endocrine resistance. Analysis of breast cancer gene expression data indicates that HOTAIR is co-expressed with FOXA1 and FOXM1 in HER2-enriched tumours, and these factors enhance the prognostic power of HOTAIR in aggressive HER2+ breast tumours. Our study elucidates the transcriptional regulation of HOTAIR, identifies HOTAIR and its regulators as novel biomarkers of patient response to endocrine therapy and corroborates the importance of transcriptional enhancers in cancer.
Objective
To develop a population pharmacokinetic model for lopinavir boosted by ritonavir in coronavirus disease 2019 (Covid-19) patients.
Methods
Concentrations of lopinavir/ritonavir were assayed ...by an accredited LC-MS/MS method. The population pharmacokinetics of lopinavir was described using non-linear mixed-effects modeling (NONMEM version 7.4). After determination of the base model that better described the data set, the influence of covariates (age, body weight, height, body mass index (BMI), gender, creatinine, aspartate aminotransferase (AST), alanine aminotransferase (ALT), C reactive protein (CRP), and trough ritonavir concentrations) was tested on the model.
Results
From 13 hospitalized patients (4 females, 9 males, age = 64 ± 16 years), 70 lopinavir/ritonavir plasma concentrations were available for analysis. The data were best described by a one-compartment model with a first-order input (KA). Among the covariates tested on the PK parameters, only the ritonavir trough concentrations had a significant effect on CL/F and improved the fit. Model-based simulations with the final parameter estimates under a regimen lopinavir/ritonavir 400/100 mg b.i.d. showed a high variability with median concentration between 20 and 30 mg/L (
C
min
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) and the 90% prediction intervals within the range 1–100 mg/L.
Conclusion
According to the estimated 50% effective concentration of lopinavir against SARS-CoV-2 virus in Vero E6 cells (16.7 mg/L), our model showed that at steady state, a dose of 400 mg b.i.d. led to 40% of patients below the minimum effective concentration while a dose of 1200 mg b.i.d. will reduce this proportion to 22%.