Novel mutations in the BRCA1 and BRCA2 genes in Iranian women with early-onset breast cancer

BACKGROUND: Breast cancer is the most common female malignancy and a major cause of death in middle-aged women. So far, germline mutations in the BRCA1 and BRCA2 genes in patients with early-onset breast and/or ovarian cancer have not been identified within the Iranian population. METHODS: With the collaboration of two main centres for cancer in Iran, we obtained clinical information, family history and peripheral blood from 83 women under the age of 45 with early-onset breast cancer for scanning of germline mutations in the BRCA1 and BRCA2 genes. We analysed BRCA1 exons 11 and BRCA2 exons 10 and 11 by the protein truncation test, and BRCA1 exons 2, 3, 5, 13 and 20 and BRCA2 exons 9, 17, 18 and 23 with the single-strand conformation polymorphism assay on genomic DNA amplified by polymerase chain reaction. RESULTS: Ten sequence variants were identified: five frameshifts (putative mutations – four novel); three missense changes of unknown significance and two polymorphisms, one seen commonly in both Iranian and British populations. CONCLUSIONS Identification of these novel mutations suggests that any given population should develop a mutation database for its programme of breast cancer screening. The pattern of mutations seen in the BRCA genes seems not to differ from other populations studied. Early-onset breast cancer (less than 45 years) and a limited family history is sufficient to justify mutation screening with a detection rate of over 25% in this group, whereas sporadic early-onset breast cancer (detection rate less than 5%) is unlikely to be cost-effective

INTRACELLULAR AND EXTRACELLULAR BIOMARKERS OF DRUG-INDUCED LIVER INJURY

Drug-induced liver injury (DILI) is a common form of adverse drug reaction (ADR) seen within the clinic. Sensitive and specific circulating biomarkers would aid in the prediction of DILI early in its course. However, the current biomarkers of DILI, such as alanine transaminase (ALT) suffer from a lack of specificity and sensitivity. Because of this, we have examined both intracellular and extracellular biomarkers of DILI in order to validate and identify novel biomarkers of DILI. Protein tyrosine nitration (PTN), an intracellular marker of oxidative stress, has been shown to be present in paracetamol-DILI, and it is thought that the causative factor for its occurrence is mitochondrial damage. In order to test this, we used Furosemide (FS), a hepatotoxin not thought to cause mitochondrial injury or glutathione (GSH) depletion with the hypothesis that this compound would not generate PTN. First, we tested the role of GSH in protecting from PTN through depleting GSH in a mouse hepatoma cell line, followed by incubation with peroxynitrite. We found that GSH depletion was required in order to elicit PTN. Following this, we compared the ability of toxic doses of FS and paracetamol to cause PTN in mice. Interestingly, we found both compounds lead to PTN, suggesting that there is a pathway independent of GSH-depletion and mitochondrial injury which may lead to PTN. MicroRNA-122 (miR-122) a potential novel extracellular biomarker of DILI, has been demonstrated to be elevated in the circulation earlier in the course of injury than current DILI biomarkers. We examined the potential for miR-122 to be released actively in exosomes during paracetamol-DILI in rats and multiple forms of DILI in humans. Our findings suggested that in both human and rodent’s, miR-122 is released in a similar profile throughout the course of DILI in exosomes, and in an exosome-free (protein-rich fraction) form. We also examined whether miR-122 is selectively released in exosomes during hepatocellular, mixed and cholestatic DILI in humans which had been prescribed a number of hepatotoxic compounds. Our study suggested that, similar to our rodent model, there is no specific pattern of exosomal release of miR-122 in any of these forms of injury. We then looked at new and relatively unexplored aspects of microRNAs, in order to evaluate how they may be used to look at damage to different zones of the liver, and damage to cells other than hepatocytes. Hepatocytes are heterogeneous, with their phenotype depending on their localisation along the porto- central axis, which has resulted in certain drugs causing zone-specific hepatotoxicity. None of the current biomarkers is able to identify zone-specific injury. We examined zonal profiles of microRNA expression within the liver of rats under basal conditions and following paracetamol. Our analysis demonstrated that 45 miRNAs are significantly differentially expressed between zone I and zone III, with three species being expressed in only one zone. Of these differentially expressed miRNAs we found that 9 species were involved in regulating 109 members Wnt/β-Catenin pathway, the molecular driver of liver zonation. We also examined changes in zonal miRNA expression following a toxic dose of paracetamol in rats. Our study was able to demonstrate that paracetamol was able to cause significant changes in the profiles of 42 and 43 miRNAs in zone I and zone III respectively. Importantly, miRNAs were both up and down regulated in both zones, suggesting that not only a loss of miRNAs is occurring during liver injury in each zone. Biliary epithelial cells (BEC) can be damaged by a plethora of different compounds, leading to vanishing bile duct syndrome, or bile duct hyperplasia. Current biomarkers for the diagnosis of BEC- injury lack in specificity, and are prone to false-positives. We developed a method to isolate BEC from the mouse liver and performed a global miRNA profile comparison of hepatocytes and BEC. As in previous studies we found miR-122-5p to be the most enriched miRNA in hepatocytes and miR-1224- 5p in BEC. On comparison of the profiles we found that 83 miRNAs were detectable in BEC but not in Hepatocytes, however further work will be required to validate any of these as markers of BEC injury

Cigarette Smoke Suppresses Type I Interferon-Mediated Antiviral Immunity in Lung Fibroblast and Epithelial Cells

The objective of this study was to investigate the impact of cigarette smoke on innate antiviral defense mechanisms; specifically, we examined the effects of cigarette smoke on the induction of type I interferon (IFN). We observed a dose-dependent decrease in the ability of human lung fibroblast and epithelial cells to elicit an antiviral response against a viral double-strand RNA (dsRNA) mimic, polyI:C, in the presence of cigarette smoke-conditioned medium (SCM). Mechanistically, SCM decreases the expression of IFN-stimulated gene 15 (ISG15) and IFN regulatory factor-7 (IRF-7) transcripts and suppresses the nuclear translocation of key transcription factors, nuclear factor-κB (NF-κB) and IRF-3, after polyI:C stimulation. Furthermore, we provide evidence that the intercellular defense strategy against viral infection is also impaired. We observed a decrease in the ability of fibroblasts to elicit an antiviral state in response to IFN-β stimulation. This was associated with decreased nuclear translocation of phosphorylated Stat1 in response to IFN-β treatment. The effects elicited by SCM are reversible and are almost entirely abrogated in the presence of an antioxidant, such as glutathione. Our findings suggest that cigarette smoke affects the immediate-early, inductive, and amplification phases of the type I IFN response

csSampling: An R Package for Bayesian Models for Complex Survey Data

We present csSampling, an R package for estimation of Bayesian models for data collected from complex survey samples. csSampling combines functionality from the probabilistic programming language Stan (via the rstan and brms R packages) and the handling of complex survey data from the survey R package. Under this approach, the user creates a survey-weighted model in brms or provides a custom weighted model via rstan. Survey design information is provided via the svydesign function of the survey package. The cs_sampling function of csSampling estimates the weighted stan model and provides an asymptotic covariance correction for model mis-specification due to using survey sampling weights as plug-in values in the likelihood. This is often known as a ``design effect'' which is the ratio between the variance from a complex survey sample and a simple random sample of the same size. The resulting adjusted posterior draws can then be used for the usual Bayesian inference while also achieving frequentist properties of asymptotic consistency and correct uncertainty (e.g. coverage).Comment: 22 pages, 5 figure

Photon rockets and gravitational radiation

The absence of gravitational radiation in Kinnersley's ``photon rocket'' solution of Einstein's equations is clarified by studying the mathematically well-defined problem of point-like photon rockets in Minkowski space (i.e. massive particles emitting null fluid anisotro\-pically and accelerating because of the recoil). We explicitly compute the (uniquely defined) {\it linearized} retarded gravitational waves emitted by such objects, which are the coherent superposition of the gravitational waves generated by the motion of the massive point-like rocket and of those generated by the energy-momentum distribution of the photon fluid. In the special case (corresponding to Kinnersley's solution) where the anisotropy of the photon emission is purely dipolar we find that the gravitational wave amplitude generated by the energy-momentum of the photons exactly cancels the usual $1/r$ gravitational wave amplitude generated by the accelerated motion of the rocket. More general photon anisotropies would, however, generate genuine gravitational radiation at infinity. Our explicit calculations show the compatibility between the non-radiative character of Kinnersley's solution and the currently used gravitational wave generation formalisms based on post-Minkowskian perturbation theory.Comment: 21 pages, LATEX, submitted to Class. Quant. Gra

His Dream of Passion: Reflections on the work of Lee Strasberg and his influence on British Actor Training (Part Two)

A previous article for Stanislavski Studies (Vol. 4, No 1, 47-62) explored and examined the impact of Lee Strasberg’s Emotion Memory technique and assessed its influence on contemporary approaches to British actor training. This second ‘companion’ article reflects on a much broader range of Strasbergian training techniques in order, initially, to examine their efficacy and to highlight the extent to which they have been absorbed and adapted by acting teachers working in a British training context. Often viewed as a controversial figure - both in the United Kingdom and in the United States - Strasberg’s approach has frequently been vilified and dismissed. This is particularly true of his interpretation of Stanislavski’s Emotion Memory technique. Whereas the earlier article sought to arrive at an informed and balanced view of his deployment of this technique, what follows is an attempt to review other aspects of Strasberg’s work so as to evaluate the coherence and credibility of the assumptions on which his approach was based and to test whether his work remains appropriate and viable in British training environments today. His work on Relaxation, Concentration and Sense Memory will be examined alongside his development of the Private Moment, Song and Dance and Animal exercises. What, if anything, can we learn from Strasberg’s Method-based approach to actor training and how might we begin to consider the impact and unity of his work as a whole as opposed to focusing almost exclusively on his early work on Emotion Memory

Observation of Amounts of Movement Practice Provided during Stroke Rehabilitation

Objective To investigate how much movement practice occurred during stroke rehabilitation, and what factors might influence doses of practice provided. Design Observational survey of stroke therapy sessions. Setting Seven inpatient and outpatient rehabilitation sites. Participants We observed a convenience sample of 312 physical and occupational therapy sessions for people with stroke. Interventions Not applicable. Main Outcome Measures We recorded numbers of repetitions in specific movement categories and data on potential modifying factors (patient age, side affected, time since stroke, FIM item scores, years of therapist experience). Descriptive statistics were used to characterize amounts of practice. Correlation and regression analyses were used to determine whether potential factors were related to the amount of practice in the 2 important categories of upper extremity functional movements and gait steps. Results Practice of task-specific, functional upper extremity movements occurred in 51% of the sessions that addressed upper limb rehabilitation, and the average number of repetitions/session was 32 (95% confidence interval [CI]=20–44). Practice of gait occurred in 84% of sessions that addressed lower limb rehabilitation and the average number of gait steps/session was 357 (95% CI=296–418). None of the potential factors listed accounted for significant variance in the amount of practice in either of these 2 categories. Conclusions The amount of practice provided during poststroke rehabilitation is small compared with animal models. It is possible that current doses of task-specific practice during rehabilitation are not adequate to drive the neural reorganization needed to promote function poststroke optimally

Small Intestinal Cannabinoid Receptor Changes Following a Single Colonic Insult with Oil of Mustard in Mice

Cannabinoids are known to be clinically beneficial for control of appetite disorders and nausea/vomiting, with emerging data that they can impact other GI disorders, such as inflammation. Post-inflammatory irritable bowel syndrome (PI-IBS) is a condition of perturbed intestinal function that occurs subsequent to earlier periods of intestinal inflammation. Cannabinoid 1 receptor (CB1R) and CB2R alterations in GI inflammation have been demonstrated in both animal models and clinically, but their continuing role in the post-inflammatory period has only been implicated to date. Therefore, to provide direct evidence for CBR involvement in altered GI functions in the absence of overt inflammation, we used a model of enhanced upper GI transit that persists for up to 4 weeks after a single insult by intracolonic 0.5% oil of mustard (OM) in mice. In mice administered OM, CB1R immunostaining in the myenteric plexus was reduced at day 7, when colonic inflammation is subsiding, and then increased at 28 days, compared to tissue from age-matched vehicle-treated mice. In the lamina propria CB2R immunostaining density was also increased at day 28. In mice tested 28 day after OM, either a CB1R-selective agonist, ACEA (1 and 3 mg/kg, s.c.) or a CB2R-selective agonist, JWH-133 (3 and 10 mg/kg, s.c.) reduced the enhanced small intestinal transit in a dose-related manner. Doses of ACEA and JWH-133 (1 mg/kg), alone or combined, reduced small intestinal transit of OM-treated mice to a greater extent than control mice. Thus, in this post-colonic inflammation model, both CBR subtypes are up-regulated and there is increased efficacy of both CB1R and CB2R agonists. We conclude that CBR remodeling occurs not only during GI inflammation but continues during the recovery phase. Thus, either CB1R- or CB2-selective agonists could be efficacious for modulating GI motility in individuals experiencing diarrhea-predominant PI-IBS

Joint working to develop R&D capacity in three rural Primary Care Trusts

Whilst much good practice relating to research support for rural PCTs undoubtedly exists, little has been published about the processes that facilitate such successful support. This paper outlines the nature of a collaborative venture between a Research & Development Support Unit, HRDNoW, and a Primary Care Research Network, CumbReN in providing research support to three rural PCTs in North Cumbria. In doing so, the paper highlights how research capacity is built through a combination of inputs at an individual and organisational level and looks specifically at the outcomes of this collaboration