Translational Model for External Volume Expansion in Irradiated Skin

Introduction: External Volume Expansion (EVE) treatment has gained popularity in breast reconstruction, enriching recipient sites for fat grafting. For patients receiving radiotherapy (XRT), results of EVE use vary, partly because the effects of EVE on irradiated tissue are not well understood. Based on our previous work with EVE and XRT, we developed a new translational model to investigate the effects of EVE in the setting of chronic radiation skin injury. Methods: Twenty-Eight SKH1-E mice received 50Gy of beta-radiation to each flank. Animals were monitored until chronic radiation fibrosis developed (8 weeks). EVE was then applied to one side for 6hrs on 5 consecutive days. The opposite side served as control. Hyperspectral Imaging (HSI) was used to assess perfusion changes before and after EVE. Mice were sacrificed at 5 days (n=14) and 15 days (n=14) after last application for histological analysis. Tissue samples were stained for vascularity (CD31) and collagen composition (Picro-Sirius red). Results: All animals developed skin fibrosis 8 weeks post-radiation, and changes in perfusion verified skin damage. EVE application induced edema on treated sides. Five days post-application, both sides were hypo-perfused as seen by HSI; with the EVE side 13% more ischemic than the untreated side (p\u3c0.001). Perfusion returned to control side levels by day 15. Blood vessels increased 20% by day 5 in EVE versus control. Collagen composition showed no difference in scar index analysis. Conclusion: EVE temporarily augments radiation-induced hypo-perfusion, likely due to transient edema. Fibrosis remained unchanged after EVE, possibly accounting for the limited expansion seen in patients. It appears that EVE induces angiogenic effect but does not affect dermal collagen composition. Future efforts should focus on reducing fibrosis post radiation to allow EVE to achieve its full potential, to benefit irradiated patients

Tumour-induced hypoglycaemia:A narrative review

Objective: To provide an overview of the pathogenesis and clinical features of tumour-induced hypoglycaemia (TIH), its effective diagnostic work-up and management strategies and the challenges involved. Background: Hypoglycaemia, defined by a plasma blood glucose level <3.0 mmol/L (<54 mg/dL), results from failure of glucose homeostasis. Although multiple scenarios contribute to the onset of hypoglycaemia, certain tumours represent an important, although relatively uncommon group of causative factors. In patients with unexplained hypoglycaemia, it is important to conduct a careful clinical assessment, with detailed investigations to ascertain the underlying cause(s), and initiate appropriate and effective therapies. TIH often presents a clinical challenge for both accurate and timely diagnosis and effective management. Methods: We performed a narrative literature review using PubMed and search-term "Tumour-Induced Hypoglycaemia", with articles written in English. Conclusions: There are two main groups of TIH: insulinoma and non-islet cell tumours (NICTs). Insulinomas are the commonest form of pancreatic neuroendocrine tumour, and a well-recognised cause of hyperinsulinaemia associated with recurrent hypoglycaemia. Conversely, NICTs mediate hypoglycaemia through the excessive production of big insulin-like growth factor 2 (IGF2), that cross-reacts with the insulin receptor. Through careful biochemical assessment, accurate diagnosis of Insulinoma versus NICTs provides a rationale for effective and individually tailored management

Systematic review and meta-analysis of the metabolic effects of modified-release hydrocortisone versus standard glucocorticoid replacement therapy in adults with adrenal insufficiency

Context Published studies exploring the metabolic effects of Modified‐Release Hydrocortisone (MR‐HC) replacement in patients with adrenal insufficiency (AI). Objective To compare metabolic effects of MR‐HC with Standard Glucocorticoid (SG) replacement in adults with AI. Randomised control trials (RCTs) were meta‐analysed; non‐RCT studies described narratively with critical appraisal. Data sources PubMed/Medline, EMBASE, CINAHL and CENTRAL were searched to identify relevant articles, published before Aug 2019. Study selection All study types that reported metabolic profile (including anthropometric, glucose and lipid‐related parameters), on patients switched from SG to MR‐HC replacement. Following independent screening from two reviewers, 390 studies were identified, of which 9 studies were included for review (RCT, n=2; non‐RCT, n=7). Data extraction Two independent reviewers assessed each paper for bias and data extraction. Results Meta‐analysis from RCTs (n=2), 104 patients were switched from SG to MR‐HC replacement. Combining treatment effects, at 3‐months post‐therapy switch there was significant reduction in body weight (‐0.82kg; 95% CI: ‐1.24kg to ‐0.40kg; p<0.001) and HbA1c (‐0.13%; 95% CI: ‐0.214% to ‐0.045%; p=0.003). In the sub‐group with Diabetes Mellitus (DM), reduction in HbA1C was more pronounced (‐0.52%; 95% CI: ‐0.82% to ‐0.23%; p<0.001). Non‐RCT studies showed improved anthropometric measures and glucose metabolism up to 48‐months following switch from SG to MR‐HC replacement. Conclusions In adults with AI, replacement with MR‐HC associates with significant improvements in anthropometric measurements and HbA1c compared with SG replacement, particularly those with DM

Early metabolic benefits of switching hydrocortisone to modified release hydrocortisone in adult adrenal insufficiency

Purpose: To compare metabolic effects of modified release hydrocortisone (MR-HC) with standard hydrocortisone (HC) therapies in adults with Adrenal Insufficiency (AI). Methods: Adult patients (n = 12) with AI, established on HC therapy, were recruited from Endocrinology clinics at University Hospitals Coventry and Warwickshire (UHCW), UK. Baseline (HC) metabolic assessments included fasting serum HbA1C, lipid and thyroid profiles, accurate measures of body composition (BodPod), and 24-h continuous measures of energy expenditure including Sleeping Metabolic Rate (SMR) using indirect calorimetry within the Human Metabolism Research Unit, UHCW. All participants then switched HC to MR-HC with repeat (MR-HC) metabolic assessments at 3 months. Paired-sample t-tests were used for data comparisons between HC and MR-HC assessments: P-value <0.05 was considered significant. Results: Following exclusion of 2 participants, analyses were based on 10 participants. Compared with baseline HC data, following 3 months of MR-HC therapy mean fat mass reduced significantly by −3.2 kg (95% CI: −6.0 to −0.4). Mean (SD) baseline HC fat mass vs repeat MR-HC fat mass: 31.9 kg (15.2) vs 28.7 kg (12.8) respectively, P = 0.03. Mean SMR increased significantly by +77 kcal/24 h (95% CI: 10–146). Mean (SD) baseline HC SMR vs repeat MR-HC SMR: 1,517 kcal/24 h (301) vs 1,594 kcal/24 h (344) respectively, P = 0.03. Mean body fat percentage reduced significantly by −3.4% (95% CI: −6.5 to −0.2). Other measures of body composition, energy expenditure, and biochemical analytes were equivalent between HC and MR-HC assessments. Conclusions: In adults with AI, switching from standard HC to MR-HC associates with early metabolic benefits of reduced fat mass and increased SMR

NR4A Gene Expression Is Dynamically Regulated in the Ventral Tegmental Area Dopamine Neurons and Is Related to Expression of Dopamine Neurotransmission Genes

The NR4A transcription factors NR4A1, NR4A2, and NR4A3 (also known as Nur77, Nurr1, and Nor1, respectively) share similar DNA-binding properties and have been implicated in regulation of dopamine neurotransmission genes. Our current hypothesis is that NR4A gene expression is regulated by dopamine neuron activity and that induction of NR4A genes will increase expression of dopamine neurotransmission genes. Eticlopride and γ-butyrolactone (GBL) were used in wild-type (+/+) and Nurr1-null heterozygous (+/−) mice to determine the mechanism(s) regulating Nur77 and Nurr1 expression. Laser capture microdissection and real-time PCR was used to measure Nurr1 and Nur77 mRNA levels in the ventral tegmental area (VTA). Nur77 expression was significantly elevated 1 h after both GBL (twofold) and eticlopride (fourfold). In contrast, GBL significantly decreased Nurr1 expression in both genotypes, while eticlopride significantly increased Nurr1 expression only in the +/+ mice. In a separate group of mice, haloperidol injection significantly elevated Nur77 and Nor1, but not Nurr1 mRNA in the VTA within 1 h and significantly increased tyrosine hydroxylase (TH) and dopamine transporter (DAT) mRNA expression by 4 h. These data demonstrate that the NR4A genes are dynamically regulated in dopamine neurons with maintenance of Nurr1 expression requiring dopamine neuron activity while both attenuation of dopamine autoreceptors activation and dopamine neuronal activity combining to induce Nur77 expression. Additionally, these data suggest that induction of NR4A genes could regulate TH and DAT expression and ultimately regulate dopamine neurotransmission

Stress-Induced Reinstatement of Drug Seeking: 20 Years of Progress

In human addicts, drug relapse and craving are often provoked by stress. Since 1995, this clinical scenario has been studied using a rat model of stress-induced reinstatement of drug seeking. Here, we first discuss the generality of stress-induced reinstatement to different drugs of abuse, different stressors, and different behavioral procedures. We also discuss neuropharmacological mechanisms, and brain areas and circuits controlling stress-induced reinstatement of drug seeking. We conclude by discussing results from translational human laboratory studies and clinical trials that were inspired by results from rat studies on stress-induced reinstatement. Our main conclusions are (1) The phenomenon of stress-induced reinstatement, first shown with an intermittent footshock stressor in rats trained to self-administer heroin, generalizes to other abused drugs, including cocaine, methamphetamine, nicotine, and alcohol, and is also observed in the conditioned place preference model in rats and mice. This phenomenon, however, is stressor specific and not all stressors induce reinstatement of drug seeking. (2) Neuropharmacological studies indicate the involvement of corticotropin-releasing factor (CRF), noradrenaline, dopamine, glutamate, kappa/dynorphin, and several other peptide and neurotransmitter systems in stress-induced reinstatement. Neuropharmacology and circuitry studies indicate the involvement of CRF and noradrenaline transmission in bed nucleus of stria terminalis and central amygdala, and dopamine, CRF, kappa/dynorphin, and glutamate transmission in other components of the mesocorticolimbic dopamine system (ventral tegmental area, medial prefrontal cortex, orbitofrontal cortex, and nucleus accumbens). (3) Translational human laboratory studies and a recent clinical trial study show the efficacy of alpha-2 adrenoceptor agonists in decreasing stress-induced drug craving and stress-induced initial heroin lapse

Suggested Improvements for the Allergenicity Assessment of Genetically Modified Plants Used in Foods

Genetically modified (GM) plants are increasingly used for food production and industrial applications. As the global population has surpassed 7 billion and per capita consumption rises, food production is challenged by loss of arable land, changing weather patterns, and evolving plant pests and disease. Previous gains in quantity and quality relied on natural or artificial breeding, random mutagenesis, increased pesticide and fertilizer use, and improved farming techniques, all without a formal safety evaluation. However, the direct introduction of novel genes raised questions regarding safety that are being addressed by an evaluation process that considers potential increases in the allergenicity, toxicity, and nutrient availability of foods derived from the GM plants. Opinions vary regarding the adequacy of the assessment, but there is no documented proof of an adverse effect resulting from foods produced from GM plants. This review and opinion discusses current practices and new regulatory demands related to food safety

Dopaminergic and Serotonergic Drug Use: A Nationwide Register-Based Study of Over 1 300 000 Older People

Objective: To investigate the use of dopaminergic and serotonergic drugs in elderly people. Methods: We analyzed data on age, sex and dispensed drugs for individuals aged $65 years registered in the Swedish Prescribed Drug Register from July to September 2008 (n = 1 347 564; 81$65 years in Sweden). Main outcome measures were dopaminergic (enhancing and/or lowering) and serotonergic (enhancing and/or lowering) drugs and combinations of these. Results: Dopaminergic and serotonergic drugs were used by 5.6 % and 13.2 % the participants, respectively. Female gender was related to use of both dopaminergic and, particularly, serotonergic drugs. Higher age was associated with use of dopamine lowering drugs and serotonergic drugs, whereas the association with use of dopamine enhancing drugs declined in the oldest old. The occurrence of combinations of dopaminergic and serotonergic drugs was generally low, with dopamine lowering + serotonin lowering drug the most common combination (1.6%). Female gender was associated with all of the combinations of dopaminergic and serotonergic drugs, whereas age showed a mixed pattern. Conclusion: Approximately one out of ten older patients uses serotonergic drugs and one out of twenty dopaminergic drugs. The frequent use of dopaminergic and serotonergic drugs in the elderly patients is a potential problem due to the fact that aging is associated with a down-regulation of both these monoaminergic systems. Future studies are needed fo

Photoactivatable drugs for nicotinic optopharmacology

Photoactivatable pharmacological agents have revolutionized neuroscience, but the palette of available compounds is limited. We describe a general method for caging tertiary amines by using a stable quaternary ammonium linkage that elicits a red shift in the activation wavelength. We prepared a photoactivatable nicotine (PA-Nic), uncageable via one- or two-photon excitation, that is useful to study nicotinic acetylcholine receptors (nAChRs) in different experimental preparations and spatiotemporal scales