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Background: Trauma can result in systemic inflammation that leads to organ dysfunction, but the impact on the brain, particularly following extracranial insults, has been largely overlooked., Methods: Building upon our prior findings, we aimed to understand the impact of systemic inflammation on neuroinflammatory gene transcripts in eight brain regions in rats exposed to (1) blast overpressure exposure [BOP], (2) cutaneous thermal injury [BU], (3) complex extremity injury, 3 hours (h) of tourniquet-induced ischemia, and hind limb amputation [CEI+tI+HLA], (4) BOP+BU or (5) BOP+CEI and delayed HLA [BOP+CEI+dHLA] at 6, 24, and 168 h post-injury (hpi)., Results: Globally, the number and magnitude of differentially expressed genes (DEGs) correlated with injury severity, systemic inflammation markers, and end-organ damage, driven by several chemokines/cytokines (Csf3, Cxcr2, Il16, and Tgfb2), neurosteroids/prostaglandins (Cyp19a1, Ptger2, and Ptger3), and markers of neurodegeneration (Gfap, Grin2b, and Homer1). Regional neuroinflammatory activity was least impacted following BOP. Non-blast trauma (in the BU and CEI+tI+HLA groups) contributed to an earlier, robust and diverse neuroinflammatory response across brain regions (up to 2-50-fold greater than that in the BOP group), while combined trauma (in the BOP+CEI+dHLA group) significantly advanced neuroinflammation in all regions except for the cerebellum. In contrast, BOP+BU resulted in differential activity of several critical neuroinflammatory-neurodegenerative markers compared to BU. t-SNE plots of DEGs demonstrated that the onset, extent, and duration of the inflammatory response are brain region dependent. Regardless of injury type, the thalamus and hypothalamus, which are critical for maintaining homeostasis, had the most DEGs. Our results indicate that neuroinflammation in all groups progressively increased or remained at peak levels over the study duration, while markers of end-organ dysfunction decreased or otherwise resolved., Conclusions: Collectively, these findings emphasize the brain's sensitivity to mediators of systemic inflammation and provide an example of immune-brain crosstalk. Follow-on molecular and behavioral investigations are warranted to understand the short- to long-term pathophysiological consequences on the brain, particularly the mechanism of blood-brain barrier breakdown, immune cell penetration-activation, and microglial activation., (© 2024. The Author(s).)

Blast-related traumatic heterotopic ossification (tHO) impacts clinical outcomes in combat-injured patients, leading to delayed wound healing, inflammatory complications, and reduced quality of life. Blast injured patients often have significant burns. This study investigated whether a partial thickness thermal burn injury exacerbates blast-related tHO in a clinically relevant polytrauma animal model. Adult male Sprague Dawley rats were subjected to an established model involving a whole-body blast overpressure exposure (BOP), complex extremity trauma followed by hind limb amputation (CET) followed by the addition of a 10 % total body surface area (TBSA) second degree thermal burn (BU). Micro-CT scans on post-operative day 56 showed a significant increase in HO volume in the CET + BU as compared to the CET alone injury group (p < .0001; 22.83 ± 3.41 mm 3 vs 4.84 ± 5.77 mm 3 ). Additionally, CET + BU concomitant with BOP significantly increased HO (p < .0001; 34.95 ± 7.71 mm 3 ) as compared to CET + BU alone, confirming BOP has a further synergistic effect. No HO was detectable in rats in the absence of CET. Serum analysis revealed similar significant elevated (p < .0001) levels of pro-inflammatory markers (Cxcl1 and Il6) at 6 h post-injury (hpi) in the CET + BU and BOP + CET + BU injury groups as compared to naïve baseline values. Real-time qPCR demonstrated similar levels of chondrogenic and osteogenic gene expression in muscle tissue at the site of injury at 168 hpi in both the CET + BU and BOP+CET + BU injury groups. These results support the hypothesis that a 10 % TBSA thermal burn markedly enhances tHO following acute musculoskeletal extremity injury in the presence and absence of blast overpressure. Furthermore, the influence of BOP on tHO cannot be accounted for either in regards to systemic inflammation induced from remote injury or inflammatory-osteo-chondrogenic expression changes local to the musculoskeletal trauma, suggesting that another mechanism beyond BOP and BU synergistic effects are at play. Therefore, these findings warrant future investigations to explore other mechanisms by which blast and burn influence tHO, and testing prophylactic measures to mitigate the local and systemic inflammatory effects of these injuries on development of HO., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Published by Elsevier Inc.)

Introduction: Heterotopic ossification (HO) is a complex pathology often observed in combat injured casualties who have sustained severe, high energy polytraumatic extremity injuries. Once HO has developed, prophylactic therapies are limited outside of surgical excision. Tourniquet-induced ischemia injury (IR) exacerbates trauma-mediated musculoskeletal tissue injury, inflammation, osteogenic progenitor cell development and HO formation. Others have shown that focal adhesion kinase-2 (FAK2) plays a key role in regulating early inflammatory signaling events. Therefore, we hypothesized that targeting FAK2 prophylactically would mitigate extremity trauma induced IR inflammation and HO formation., Methods: We tested whether the continuous infusion of a FAK2 inhibitor (Defactinib, PF-573228; 6.94 µg/kg/min for 14 days) can mitigate ectopic bone formation (HO) using an established blast-related extremity injury model involving femoral fracture, quadriceps crush injury, three hours of tourniquet-induced limb ischemia, and hindlimb amputation through the fracture site. Tissue inflammation, infiltrating cells, osteogenic progenitor cell content were assessed at POD-7. Micro-computed tomography imaging was used to quantify mature HO at POD-56., Results: In comparison to vehicle control-treated rats, FAK2 administration resulted in no marked wound healing complications or weight loss. FAK2 treatment decreased HO by 43%. At POD-7, marked reductions in tissue proinflammatory gene expression and assayable osteogenic progenitor cells were measured, albeit no significant changes in expression patterns of angiogenic, chondrogenic and osteogenic genes. At the same timepoint, injured tissue from FAK-treated rats had fewer infiltrating cells. Additionally, gene expression analyses of tissue infiltrating cells resulted in a more measurable shift from an M1 inflammatory to an M2 anti-inflammatory macrophage phenotype in the FAK2 inhibitor-treated group., Discussion: Our findings suggest that FAK2 inhibition may be a novel strategy to dampen trauma-induced inflammation and attenuate HO in patients at high risk as a consequence of severe musculoskeletal polytrauma., Competing Interests: Authors CR, UN and DS was employed by the company Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Rowe, Nwaolu, Salinas, Hong, Nunez, Lansford, McCarthy, Potter, Levi and Davis.)

Blast exposure, commonly experienced by military personnel, can cause devastating life-threatening polysystem trauma. Despite considerable research efforts, the impact of the systemic inflammatory response after major trauma on secondary brain injury-inflammation is largely unknown. The aim of this study was to identify markers underlying the susceptibility and early onset of neuroinflammation in three rat trauma models: (1) blast overpressure exposure (BOP), (2) complex extremity trauma (CET) involving femur fracture, crush injury, tourniquet-induced ischemia, and transfemoral amputation through the fracture site, and (3) BOP+CET. Six hours post-injury, intact brains were harvested and dissected to obtain biopsies from the prefrontal cortex, striatum, neocortex, hippocampus, amygdala, thalamus, hypothalamus, and cerebellum. Custom low-density microarray datasets were used to identify, interpret and visualize genes significant (p < 0.05 for differential expression [DEGs]; 86 neuroinflammation-associated) using a custom python-based computer program, principal component analysis, heatmaps and volcano plots. Gene set and pathway enrichment analyses of the DEGs was performed using R and STRING for protein-protein interaction (PPI) to identify and explore key genes and signaling networks. Transcript profiles were similar across all regions in naïve brains with similar expression levels involving neurotransmission and transcription functions and undetectable to low-levels of inflammation-related mediators. Trauma-induced neuroinflammation across all anatomical brain regions correlated with injury severity (BOP+CET > CET > BOP). The most pronounced differences in neuroinflammatory-neurodegenerative gene regulation were between blast-associated trauma (BOP, BOP+CET) and CET. Following BOP, there were few DEGs detected amongst all 8 brain regions, most were related to cytokines/chemokines and chemokine receptors, where PPI analysis revealed Il1b as a potential central hub gene. In contrast, CET led to a more excessive and diverse pro-neuroinflammatory reaction in which Il6 was identified as the central hub gene. Analysis of the of the BOP+CET dataset, revealed a more global heightened response (Cxcr2, Il1b, and Il6) as well as the expression of additional functional regulatory networks/hub genes (Ccl2, Ccl3, and Ccl4) which are known to play a critical role in the rapid recruitment and activation of immune cells via chemokine/cytokine signaling. These findings provide a foundation for discerning pathophysiological consequences of acute extremity injury and systemic inflammation following various forms of trauma in the brain., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2023. Published by Elsevier Inc.)

Tourniquets are critical for the control of traumatic extremity hemorrhage. In this study, we sought to determine, in a rodent blast-related extremity amputation model, the impact of prolonged tourniquet application and delayed limb amputation on survival, systemic inflammation, and remote end organ injury. Adult male Sprague Dawley rats were subjected to blast overpressure (120±7 kPa) and orthopedic extremity injury consisting femur fracture, one-minute soft tissue crush injury (20 psi), ± 180 min of tourniquet-induced hindlimb ischemia followed by delayed (60 min of reperfusion) hindlimb amputation (dHLA). All animals in the non-tourniquet group survived whereas 7/21 (33%) of the animals in the tourniquet group died within the first 72 h with no deaths observed between 72 and 168 h post-injury. Tourniquet induced ischemia-reperfusion injury (tIRI) likewise resulted in a more robust systemic inflammation (cytokines and chemokines) and concomitant remote pulmonary, renal, and hepatic dysfunction (BUN, CR, ALT. AST, IRI/inflammation-mediated genes). These results indicate prolonged tourniquet application and dHLA increases risk of complications from tIRI, leading to greater risk of local and systemic complications including organ dysfunction or death. We thus need enhanced strategies to mitigate the systemic effects of tIRI, particularly in the military prolonged field care (PFC) setting. Furthermore, future work is needed to extend the window within which tourniquet deflation to assess limb viability remains feasible, as well as new, limb-specific or systemic point of care tests to better assess the risks of tourniquet deflation with limb preservation in order to optimize patient care and save both limb and life., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2023. Published by Elsevier Ltd. All rights reserved.)

Trauma triggers critical molecular and cellular signaling cascades that drive biological outcomes and recovery. Variations in the gene expression of common endogenous reference housekeeping genes (HKGs) used in data normalization differ between tissue types and pathological states. Systematically, we investigated the gene stability of nine HKGs ( Actb , B2m , Gapdh , Hprt1 , Pgk1 , Rplp0 , Rplp2 , Tbp , and Tfrc ) from tissues prone to remote organ dysfunction (lung, liver, kidney, and muscle) following extremity trauma. Computational algorithms (geNorm, Normfinder, ΔCt, BestKeeper, RefFinder) were applied to estimate the expression stability of each HKG or combinations of them, within and between tissues, under both steady-state and systemic inflammatory conditions. Rplp2 was ranked as the most suitable in the healthy and injured lung, kidney, and skeletal muscle, whereas Rplp2 and either Hprt1 or Pgk1 were the most suitable in the healthy and injured liver, respectively. However, the geometric mean of the three most stable genes was deemed the most stable internal reference control. Actb and Tbp were the least stable in normal tissues, whereas Gapdh and Tbp were the least stable across all tissues post-trauma. Ct values correlated poorly with the translation from mRNA to protein. Our results provide a valuable resource for the accurate normalization of gene expression in trauma-related experiments.

Prolonged hyperglycemia causes long-term vision complications and an increased risk of cognitive deficits. High blood sugar also confers an osmotic load/stress to cells. We assessed behavioral and neurochemical changes in zebrafish brain and retina following prolonged hyperglycemia for 4-weeks or 8-weeks. At each time point, behavior was assessed using 3-chamber choice task and optomotor response; tissue was then collected and levels of inflammatory markers, tight junction proteins, and neurotransmitters determined using Western Blots. After 4-weeks, brain levels of v-rel reticuloendotheliosis viral oncogene homolog A (avian) (RelA; NF-kB subunit), IkB kinase (IKK), and glial fibrillary acidic protein (GFAP) were significantly elevated; differences in zonula occludens-1 (ZO-1), claudin-5, glutamic acid decarboxylase (GAD), and tyrosine hydroxylase (TH) were not significant. In retina, significant differences were observed only for TH (decreased), Rel A (increased), and GFAP (increased) levels. Glucose-specific differences in initial choice latency and discrimination ratios were also observed. After 8-weeks, RelA, GAD, and TH were significantly elevated in both tissues; IKK and GFAP levels were also elevated, though not significantly. ZO-1 and claudin-5 levels osmotically decreased in retina but displayed an increasing trend in glucose-treated brains. Differences in discrimination ratio were driven by osmotic load. OMRs increased in glucose-treated fish at both ages. In vivo analysis of retinal vasculature suggested thicker vessels after 4-weeks, but thinner vessels at 8-weeks. In vitro , glucose treatment reduced formation of nodes and meshes in 3B-11 endothelial cells, suggesting a reduced ability to form a vascular network. Overall, hyperglycemia triggered a strong inflammatory response causing initial trending changes in tight junction and neuronal markers. Most differences after 4-weeks of exposure were observed in glucose-treated fish suggesting effects on glucose metabolism independent of osmotic load. After 8-weeks, the inflammatory response remained and glucose-specific effects on neurotransmitter markers were observed. Osmotic differences impacted cognitive behavior and retinal protein levels; protein levels in brain displayed glucose-driven changes. Thus, we not only observed differential sensitivities of retina and brain to glucose-insult, but also different cellular responses, suggesting hyperglycemia causes complex effects at the cellular level and/or that zebrafish are able to compensate for the continued high blood glucose levels., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Rowe, Delbridge-Perry, Bonan, Cohen, Bentley, DeCicco-Skinner, Davidson and Connaughton.)

Visual system development is a highly complex process involving coordination of environmental cues, cell pathways, and integration of functional circuits. Consequently, a change to any step, due to a mutation or chemical exposure, can lead to deleterious consequences. One class of chemicals known to have both overt and subtle effects on the visual system is endocrine disrupting compounds (EDCs). EDCs are environmental contaminants which alter hormonal signaling by either preventing compound synthesis or binding to postsynaptic receptors. Interestingly, recent work has identified neuronal and sensory systems, particularly vision, as targets for EDCs. In particular, estrogenic and thyroidogenic signaling have been identified as critical modulators of proper visual system development and function. Here, we summarize and review this work, from our lab and others, focusing on behavioral, physiological, and molecular data collected in zebrafish. We also discuss different exposure regimes used, including long-lasting effects of developmental exposure. Overall, zebrafish are a model of choice to examine the impact of EDCs and other compounds targeting estrogen and thyroid signaling and the consequences of exposure in visual system development and function., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Cohen, Popowitz, Delbridge-Perry, Rowe and Connaughton.)

Zebrafish (Danio rerio) are an excellent model to investigate the effects of chronic hyperglycemia, a hallmark of Type II Diabetes Mellitus (T2DM). This alternate immersion protocol is a noninvasive, step-wise method of inducing hyperglycemia for up to eight weeks. Adult zebrafish are alternately exposed to sugar (glucose) and water for 24 hours each. The zebrafish begin treatment in a 1% glucose solution for 2 weeks, then a 2% solution for 2 weeks, and finally a 3% solution for the remaining 4 weeks. Compared to water-treated (stress) and mannitol-treated (osmotic) controls, glucose-treated zebrafish have significantly higher blood sugar levels. The glucose-treated zebrafish show blood sugar levels of 3-times that of controls, suggesting that after both four and eight weeks hyperglycemia can be achieved. Sustained hyperglycemia was associated with increased Glial Fibrillary Acidic Protein (GFAP) and increased nuclear factor Kappa B (NF-kB) levels in retina and decreased physiological responses, as well as cognitive deficits suggesting this protocol can be used to model disease complications.

Importance: Despite the widespread use of systemic antibiotics to prevent infections in surgically treated patients with fracture, high rates of surgical site infection persist., Objective: To examine the effect of intrawound vancomycin powder in reducing deep surgical site infections., Design, Setting, and Participants: This open-label randomized clinical trial enrolled adult patients with an operatively treated tibial plateau or pilon fracture who met the criteria for a high risk of infection from January 1, 2015, through June 30, 2017, with 12 months of follow-up (final follow-up assessments completed in April 2018) at 36 US trauma centers., Interventions: A standard infection prevention protocol with (n = 481) or without (n = 499) 1000 mg of intrawound vancomycin powder., Main Outcomes and Measures: The primary outcome was a deep surgical site infection within 182 days of definitive fracture fixation. A post hoc comparison assessed the treatment effect on gram-positive and gram-negative-only infections. Other secondary outcomes included superficial surgical site infection, nonunion, and wound dehiscence., Results: The analysis included 980 patients (mean [SD] age, 45.7 [13.7] years; 617 [63.0%] male) with 91% of the expected person-time of follow-up for the primary outcome. Within 182 days, deep surgical site infection was observed in 29 of 481 patients in the treatment group and 46 of 499 patients in the control group. The time-to-event estimated probability of deep infection by 182 days was 6.4% in the treatment group and 9.8% in the control group (risk difference, -3.4%; 95% CI, -6.9% to 0.1%; P = .06). A post hoc analysis of the effect of treatment on gram-positive (risk difference, -3.7%; 95% CI, -6.7% to -0.8%; P = .02) and gram-negative-only (risk difference, 0.3%; 95% CI, -1.6% to 2.1%; P = .78) infections found that the effect of vancomycin powder was a result of its reduction in gram-positive infections., Conclusions and Relevance: Among patients with operatively treated tibial articular fractures at a high risk of infection, intrawound vancomycin powder at the time of definitive fracture fixation reduced the risk of a gram-positive deep surgical site infection, consistent with the activity of vancomycin., Trial Registration: ClinicalTrials.gov Identifier: NCT02227446.

Neurodegenerative diseases are age-dependent, debilitating, and incurable. Recent reports have also correlated hyperglycemia with changes in memory and/or cognitive impairment. We have modified and developed a three-chamber choice cognitive task similar to that used with rodents for use with hyperglycemic zebrafish. The testing chamber consists of a centrally located starting chamber and two choice compartments on either side, with a shoal of conspecifics used as the reward. We provide data showing that once acquired, zebrafish remember the task at least 8 weeks later. Our data indicate that zebrafish respond robustly to this reward, and we have identified cognitive deficits in hyperglycemic fish after 4 weeks of treatment. This behavioral assay may also be applicable to other studies related to cognition and memory.

Severe polytraumatic injury initiates a robust immune response. Broad immune dysfunction in patients with such injuries has been well-documented; however, early biomarkers of immune dysfunction post-injury, which are critical for comprehensive intervention and can predict the clinical course of patients, have not been reported. Current circulating markers such as IL-6 and IL-10 are broad, non-specific, and lag behind the clinical course of patients. General blockade of the inflammatory response is detrimental to patients, as a certain degree of regulated inflammation is critical and necessary following trauma. Exosomes, small membrane-bound extracellular vesicles, found in a variety of biofluids, carry within them a complex functional cargo, comprised of coding and non-coding RNAs, proteins, and metabolites. Composition of circulating exosomal cargo is modulated by changes in the intra- and extracellular microenvironment, thereby serving as a homeostasis sensor. With its extensively documented involvement in immune regulation in multiple pathologies, study of exosomal cargo in polytrauma patients can provide critical insights on trauma-specific, temporal immune dysregulation, with tremendous potential to serve as unique biomarkers and therapeutic targets for timely and precise intervention.

We describe a visual stimulus that can be used with both larval and adult zebrafish (Danio rerio). This protocol is a modification of a standard visual behavior analysis, the optomotor response (OMR). The OMR is often used to determine the spatial response or to detect directional visuomotor deficiencies. An OMR can be generated using a high contrast grated pattern, typically vertical bars. The spatial sensitivity is measured by detection and response to a change in grating bar width and is reported in cycles per degree (CPD). This test has been used extensively with zebrafish larvae and adults to identify visual- and/or motor-based mutations. Historically, when tested in adults, the grated pattern was presented from a vertical perspective, using a rotating cylinder around a holding tank, allowing the grating to be seen solely from the sides and front of the organism. In contrast, OMRs in zebrafish larvae are elicited using a stimulus projected below the fish. This difference in methodology means that two different experimental set-ups are required: one for adults and one for larvae. Our visual stimulus modifies the stimulation format so that a single OMR stimulus, suitable for use with both adults and larvae, is being presented underneath the fish. Analysis of visuomotor responses using this method does not require costly behavioral tracking software and, using a single behavioral paradigm, allows the observer to rapidly determine visual spatial response in both zebrafish larvae and adults., (© 2013-2021 The Journal of Biological Methods, All rights reserved.)

Ischemia reperfusion (IR) injury results in devastating skeletal muscle fibrosis. Here, we recapitulate this injury with a mouse model of hindlimb IR injury which leads to skeletal muscle fibrosis. Injury resulted in extensive immune infiltration with robust neutrophil extracellular trap (NET) formation in the skeletal muscle, however, direct targeting of NETs via the peptidylarginine deiminase 4 (PAD4) mechanism was insufficient to reduce muscle fibrosis. Circulating levels of IL-10 and TNFα were significantly elevated post injury, indicating toll-like receptor (TLR) signaling may be involved in muscle injury. Administration of hydroxychloroquine (HCQ), a small molecule inhibitor of TLR7/8/9, following injury reduced NET formation, IL-10, and TNFα levels and ultimately mitigated muscle fibrosis and improved myofiber regeneration following IR injury. HCQ treatment decreased fibroadipogenic progenitor cell proliferation and partially inhibited ERK1/2 phosphorylation in the injured tissue, suggesting it may act through a combination of TLR7/8/9 and ERK signaling mechanisms. We demonstrate that treatment with FDA-approved HCQ leads to decreased muscle fibrosis and increased myofiber regeneration following IR injury, suggesting short-term HCQ treatment may be a viable treatment to prevent muscle fibrosis in ischemia reperfusion and traumatic extremity injury., (© 2020 Federation of American Societies for Experimental Biology.)

Persistent postconcussion syndrome (PPCS) after mild traumatic brain injury (mTBI) is a significant public health and military problem for which there is limited treatment evidence. The aim of this study was to determine whether forty 150 kPa hyperbaric oxygen therapies (HBOTs) can improve symptoms and cognitive function in subjects with the PPCS of mTBI, using a randomized controlled crossover design with 2-month follow-up. Sixty-three civilian and military subjects with mTBI/PPCS were randomized to either 40 HBOTs at 150 kPa/60 minutes, once daily, 5 days per week in 8 weeks or an equivalent no-treatment control period. The Control Group was then crossed over to HBOT. Subjects underwent symptom, neuropsychological, and psychological testing, before and after treatment or control with retesting 2 months after the 40 th HBOT. Fifty subjects completed the protocol with primary outcome testing. HBOT subjects experienced significant improvements in Neurobehavioral Symptom Inventory, Memory Index, Automated Neuropsychological Assessment Metrics, Hamilton Depression Scale, Hamilton Anxiety Scale, Post-Traumatic Stress Disorder Checklist, Pittsburgh Sleep Quality Index, and Quality Of Life after Brain Injury compared to the Control Group. After crossing over to HBOT the Control Group experienced near-identical significant improvements. Further improvements were experienced by both groups during the 2-month follow-up period. These data indicate that 40 HBOTs at 150 kPa/60 minutes demonstrated statistically significant improvements in postconcussion and Post-Traumatic Stress Disorder symptoms, memory, cognitive functions, depression, anxiety, sleep, and quality of life in civilian and military subjects with mTBI/PPCS compared to controls. Improvements persisted at least 2 months after the 40 th HBOT. The study was registered on ClinicalTrials.gov (NCT02089594) on March 18, 2014 and with the U.S. Food and Drug Administration under Investigational New Drug #113823. The Institutional Review Boards of the United States Army Medical Research and Materiel Command Office of Research Protections Human Research Protection Office and the Louisiana State University School of Medicine (approval No. 7381) approved the study on May 13, 2014 and December 20, 2013, respectively., Competing Interests: None

Background: Keratinocyte cancers (KC) are common and pose a significant financial burden globally. Ultraviolet radiation is a significant factor in their development, through mutagenesis promotion but also through local and systemic immunosuppression. Although systemic immunosuppression is well understood, cutaneous immunity has been more difficult to evaluate., Objectives: This study used a contact sensitizer, diphencyprone (DPCP), which elicits a contact hypersensitivity reaction in skin, to compare the degree of reactivity to DPCP in patients with a high KC burden versus those with a low KC burden., Methods: A prospective study was performed in immunocompetent patients aged 70 ± 5 years of age, comparing patients with a high KC burden (>10 previous KC) with those with a low KC burden (<2 previous KC). All patients were sensitized with 2% DPCP and then patch tested two weeks later with eight different concentrations of DPCP with the threshold concentration and total degree of reaction recorded., Results: Nine patients were recruited, 5 in the 'high cancer' group and 4 in the 'low cancer' group. All patients were Fitzpatrick skin type 1 or 2. All patients developed a reaction to DPCP. Patients in the low cancer group developed a reaction at a significantly lower threshold DPCP concentration than the high cancer group (P = 0.039). The cumulative intensity of reaction was higher in the low cancer group (P = 0.087)., Conclusion: Patients with a high KC burden required a higher threshold concentration of DPCP to elicit a hypersensitivity reaction, supporting the concept of a lower skin immunity in these patients. DPCP reactivity threshold could be a useful tool in the evaluation of skin immunity and propensity to develop keratinocyte cancers., (© 2019 European Academy of Dermatology and Venereology.)

Social marketing is a commonly used strategy in global health. Social marketing programmes may sell subsidized products through commercial sector outlets, distribute appropriately priced products, deliver health services through social franchises and promote behaviours not dependent upon a product or service. We aimed to review evidence of the effectiveness of social marketing in low- and middle-income countries, focusing on major areas of investment in global health: HIV, reproductive health, child survival, malaria and tuberculosis. We searched PubMed, PsycInfo and ProQuest, using search terms linking social marketing and health outcomes for studies published from 1995 to 2013. Eligible studies used experimental or quasi-experimental designs to measure outcomes of behavioural factors, health behaviours and/or health outcomes in each health area. Studies were analysed by effect estimates and for application of social marketing benchmark criteria. After reviewing 18 974 records, 125 studies met inclusion criteria. Across health areas, 81 studies reported on changes in behavioural factors, 97 studies reported on changes in behaviour and 42 studies reported on health outcomes. The greatest number of studies focused on HIV outcomes (n = 45) and took place in sub-Saharan Africa (n = 67). Most studies used quasi-experimental designs and reported mixed results. Child survival had proportionately the greatest number of studies using experimental designs, reporting health outcomes, and reporting positive, statistically significant results. Most programmes used a range of methods to promote behaviour change. Programmes with positive, statistically significant findings were more likely to apply audience insights and cost-benefit analyses to motivate behaviour change. Key evidence gaps were found in voluntary medical male circumcision and childhood pneumonia. Social marketing can influence health behaviours and health outcomes in global health; however evaluations assessing health outcomes remain comparatively limited. Global health investments are needed to (i) fill evidence gaps, (ii) strengthen evaluation rigour and (iii) expand effective social marketing approaches., (© The Author 2016. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine.)

Sentinel lymph node status is a major prognostic marker in locally invasive cutaneous melanoma. However, this procedure is not always feasible, requires advanced logistics and carries rare but significant morbidity. Previous studies have linked markers of tumour biology to patient survival. In this study, we aimed to combine the predictive value of established biomarkers in addition to clinical parameters as indicators of survival in addition to or instead of sentinel node biopsy in a cohort of high-risk melanoma patients. Patients with locally invasive melanomas undergoing sentinel lymph node biopsy were ascertained and prospectively followed. Information on mortality was validated through the National Death Index. Immunohistochemistry was used to analyse proteins previously reported to be associated with melanoma survival, namely Ki67, p16 and CD163. Evaluation and multivariate analyses according to REMARK criteria were used to generate models to predict disease-free and melanoma-specific survival. A total of 189 patients with available archival material of their primary tumour were analysed. Our study sample was representative of the entire cohort (N = 559). Average Breslow thickness was 2.5 mm. Thirty-two (17%) patients in the study sample died from melanoma during the follow-up period. A prognostic score was developed and was strongly predictive of survival, independent of sentinel node status. The score allowed classification of risk of melanoma death in sentinel node-negative patients. Combining clinicopathological factors and established biomarkers allows prediction of outcome in locally invasive melanoma and might be implemented in addition to or in cases when sentinel node biopsy cannot be performed., (© 2016 UICC.)

Cutaneous melanoma is a heterogeneous disease affecting the regulation of multiple genes and proteins that contribute to melanoma progression. Survival for patients with locally invasive disease varies greatly, even within tumour stages based on current prognostic criteria. This has prompted investigations into the value of additional clinical or biological parameters predicting survival. In particular, the improved knowledge of tumour biology has fed the hope that the outcome may be predicted at the molecular level. The prognostic value of numerous potential biomarkers has therefore been evaluated in protein and gene expression studies, and genomic associations with melanoma prognosis are beginning to emerge. These potential biomarkers interrogate key tumour and host processes important for tumour development and progression, such as proliferation, invasion and migration through epithelial mesenchymal transition or the host immune or vascular responses. This research may allow more individualised information on prognosis if the challenges regarding the quality and validation of studies are overcome., (© 2015 The Australasian College of Dermatologists.)

Background: A substantial number of melanoma patients will develop multiple primary melanomas (MPM). Currently, little is known about the impact of MPM on survival., Objective: We aimed to determine whether melanoma survival is worse for patients with MPM compared to those with a single invasive primary melanoma (SPM)., Materials and Methods: A cohort study was conducted. Patients were sourced from an Australian population, with follow-up information collected retrospectively from registry data. Melanoma-specific survival analysis was performed to find associated variables after adjustment for known prognostic factors, using four different models, each selecting a different index melanoma lesion., Results: 1068 stage I and II melanoma patients were followed up for a median of 24.4 years. MPM was found in 17.8% of the cohort (190 patients), more likely among males and older age groups. Other clinicopathological parameters were similar between the MPM and SPM (878 patients) cohorts. After adjustment for age, sex and Breslow thickness, MPM was a hazard for death from melanoma, across all models, reaching significance when considering the last invasive lesion as the index melanoma (HR = 2.76, P = 0.017)., Conclusion: Patients with multiple invasive lesions seem more at risk of death from melanoma, independent of known prognostic factors., (© 2015 European Academy of Dermatology and Venereology.)

Erythroderma is a potentially serious and life-threatening skin disease with a number of possible aetiologies. Drug reactions are well-documented causes, with carbamazepine, penicillin and allopurinol being the most commonly implicated. This case describes a unique presentation of warfarin-induced erythroderma in a 78-year-old female patient., (© 2014 The Australasian College of Dermatologists.)

Background: Approximately 10% of ischemic strokes are caused by carotid artery stenosis (CAS). Estimated prevalence of asymptomatic CAS is 1%., Purpose: To evaluate evidence on screening and treating asymptomatic adults for CAS., Data Sources: MEDLINE, the Cochrane Library, EMBASE, and trial registries through September 2013; MEDLINE through March 2014 for trials., Study Selection: Good- or fair-quality trials of screening, carotid endarterectomy (CEA), or stenting compared with medical therapy or of intensification of medical therapy; systematic reviews; multi-institution studies reporting harms; and externally validated risk-stratification tools., Data Extraction: Dual extraction and quality assessment., Data Synthesis: No trials compared screening with no screening or stenting with medical therapy or assessed intensification of medical therapy, and no externally validated, reliable risk-stratification tools were found. Given the specificity of ultrasonography (range, 88% to 94% for CAS ≥ 50% to ≥ 70%), its use in low-prevalence populations would yield many false-positive results. Absolute reduction of nonperioperative strokes was 5.5% (95% CI, 3.9% to 7.0%; 3 trials; 5223 participants) over approximately 5 years for CEA compared with medical therapy. The 30-day rates of stroke or death after CEA in trials and cohort studies were 2.4% (CI, 1.7% to 3.1%; 6 trials; 3435 participants) and 3.3% (CI, 2.7% to 3.9%; 7 studies; 17474 participants), respectively. Other harms of interventions included myocardial infarction, nerve injury, and hematoma., Limitations: Trials may have overestimated benefits and used highly selected surgeons. Medical therapy used in trials was outdated, and stroke rates have declined in recent decades. Harms may have been underreported., Conclusion: Current evidence does not establish incremental overall benefit of CEA, stenting, or intensification of medical therapy. Potential for overall benefit is limited by low prevalence and harms., Primary Funding Source: Agency for Healthcare Research and Quality.

Aim: To assess whether response to medications for alcohol use disorders varies by genotype., Methods: Systematic review and meta-analysis., Results: We found no studies that assessed the clinical utility of genotype-guided dosing strategies or genotype-guided medication selection, and none randomized by genotype. All included studies assessed the association between genotype and response to medication. Of 15 included studies, eight (n = 1365 participants) assessed variation in naltrexone response and polymorphisms of OPRM1. Our meta-analyses for return to heavy drinking found no significant difference between A allele homozygotes and those with at least one G allele, both without (risk difference: 0.26; 95% CI: -0.01-0.53; n = 174) and with inclusion of studies rated as high or unclear risk of bias (risk difference: 0.14; 95% CI: -0.03-0.3; n = 382). For all other polymorphism-medication pairs, we found just one eligible study., Conclusion: Estimates of effect for return to heavy drinking suggest it is possible that patients with at least one G allele of A118G polymorphism of OPRM1 might be more likely to respond to naltrexone, but confidence intervals were wide; additional studies are needed to improve confidence in the estimates.

Importance: Alcohol use disorders cause substantial morbidity and early mortality yet remain greatly undertreated. Medications are considerably underused., Objective: To conduct a systematic review and meta-analysis of the benefits and harms of medications (US FDA-approved and others) for adults with alcohol use disorders., Data Sources: PubMed, Cochrane Library, PsycINFO, CINAHL, EMBASE, FDA website, and clinical trials registries (January 1, 1970, to March 1, 2014)., Study Selection: Two reviewers selected randomized clinical trials (RCTs) with at least 12 weeks' duration that reported eligible outcomes and head-to-head prospective cohort studies reporting health outcomes or harms., Data Extraction and Synthesis: We conducted meta-analyses using random-effects models and calculated numbers needed to treat for benefit (NNTs) or harm (NNHs)., Main Outcomes and Measures: Alcohol consumption, motor vehicle crashes, injuries, quality of life, function, mortality, and harms., Results: We included 122 RCTs and 1 cohort study (total 22,803 participants). Most assessed acamprosate (27 studies, n = 7519), naltrexone (53 studies, n = 9140), or both. The NNT to prevent return to any drinking for acamprosate was 12 (95% CI, 8 to 26; risk difference [RD], -0.09; 95% CI, -0.14 to -0.04) and was 20 (95% CI, 11 to 500; RD, -0.05; 95% CI, -0.10 to -0.002) for oral naltrexone (50 mg/d). The NNT to prevent return to heavy drinking was 12 (95% CI, 8 to 26; RD -0.09; 95% CI, -0.13 to -0.04) for oral naltrexone (50 mg/d). Meta-analyses of trials comparing acamprosate to naltrexone found no statistically significant difference between them for return to any drinking (RD, 0.02; 95% CI, -0.03 to 0.08) or heavy drinking (RD, 0.01; 95% CI, -0.05 to 0.06). For injectable naltrexone, meta-analyses found no association with return to any drinking (RD, -0.04; 95% CI, -0.10 to 0.03) or heavy drinking (RD, -0.01; 95% CI, -0.14 to 0.13) but found an association with reduction in heavy drinking days (weighted mean difference [WMD], -4.6%; 95% CI, -8.5% to -0.56%). Among medications used off-label, moderate evidence supports an association with improvement in some consumption outcomes for nalmefene (heavy drinking days per month: WMD, -2.0; 95% CI, -3.0 to -1.0; drinks per drinking day: WMD, -1.02; 95% CI, -1.77 to -0.28) and topiramate (% heavy drinking days: WMD, -9.0%; 95% CI, -15.3% to -2.7%; drinks per drinking day: WMD, -1.0; 95% CI, -1.6 to -0.48). For naltrexone and nalmefene, NNHs for withdrawal from trials due to adverse events were 48 (95% CI, 30 to 112) and 12 (95% CI, 7 to 50), respectively; risk was not significantly increased for acamprosate or topiramate., Conclusions and Relevance: Both acamprosate and oral naltrexone were associated with reduction in return to drinking. When directly compared with one another, no significant differences were found between acamprosate and naltrexone for controlling alcohol consumption. Factors such as dosing frequency, potential adverse events, and availability of treatments may guide medication choice.

Objective: To determine whether rural practice terms for junior doctors result in increased interest in rural practice and whether these terms improve learning experiences, clinical skills and insight into difficulties of rural practice., Design: Semistructured, self-administered survey with questions on respondent demographics, clinical experience during rural practice terms, post-rural experience and personal opinion., Setting: South East Queensland., Participants: Thirty junior doctors from three tertiary hospitals were approached. The response rate was 100%., Main Outcome Measures: Exploration of junior doctors' rural term experience., Results: Two thirds (67%) of the respondents reported feeling uncomfortable with respect to clinical practice requirements during their rural terms. Half (47%) performed procedures they had only previously performed in simulation environments, and the majority (87%) relied on textbooks or other resources on a daily basis. Two thirds (67%) changed aspects of their usual clinical practice while practising in a rural setting, and 80% reported a change in attitude towards the hardships faced by rural practitioners. The majority of the respondents (87%) enjoyed their rural term, gaining confidence as a result of it, and more than half (53%) reported considering working in rural areas in the future., Conclusions: The results of this survey suggest that junior doctors on rural rotations are required to perform at a clinical level higher than that required of them in metropolitan hospitals. While their clinical experience appears to result in a greater interest in future rural career possibilities for junior doctors, this survey highlights the requirement to improve support for junior doctors undertaking terms in rural areas., (© 2014 National Rural Health Alliance Inc.)

Background: Modular polyketide synthases catalyse the biosynthesis of medically useful natural products by stepwise chain assembly, with each module of enzyme activities catalysing a separate cycle of polyketide chain extension. Domain swapping between polyketide synthases leads to hybrid multienzymes that yield novel polyketides in a more or less predictable way. No experiments have so far been reported which attempt to enlarge a polyketide synthase by interpolating additional modules., Results: We describe here the construction of tetraketide synthases in which an entire extension module from the rapamycin-producing polyketide synthase is covalently spliced between the first two extension modules of the erythromycin-producing polyketide synthase (DEBS). The extended polyketide synthases thus formed are found to catalyse the synthesis of specific tetraketide products containing an appropriate extra ketide unit. Co-expression in Saccharopolyspora erythraea of the extended DEBS multienzyme with multienzymes DEBS 2 and DEBS 3 leads to the formation, as expected, of novel octaketide macrolactones. In each case the predicted products are accompanied by significant amounts of unextended products, corresponding to those of the unaltered DEBS PKS. We refer to this newly observed phenomenon as 'skipping'., Conclusions: The strategy exemplified here shows far-reaching possibilities for combinatorial engineering of polyketide natural products, as well as revealing the ability of modular polyketide synthases to 'skip' extension modules. The results also provide additional insight into the three-dimensional arrangement of modules within these giant synthases.

Background: The macrolide antibiotic erythromycin A, like other complex aliphatic polyketides, is synthesised by a bacterial modular polyketide synthase (PKS). Such PKSs, in contrast to other fatty acid and polyketide synthases which work iteratively, contain a separate set or module of enzyme activities for each successive cycle of polyketide chain extension, and the number and type of modules together determine the structure of the polyketide product. Thus, the six extension modules of the erythromycin PKS (DEBS) together catalyse the production of the specific heptaketide 6-deoxyerythronolide B., Results: A mutant strain of the erythromycin producer Saccharopolyspora erythraea, which accumulates the aglycone intermediate erythronolide B, was found unexpectedly to produce two novel octaketides, both 16-membered macrolides. These compounds were detectable in fermentation broths of wild-type S. erythraea, but not in a strain from which the DEBS genes had been specifically deleted. From their structures, both of these octaketides appear to be aberrant products of DEBS in which module 4 has 'stuttered', that is, has catalysed two successive cycles of chain extension., Conclusions: The isolation of novel DEBS-derived octaketides provides the first evidence that an extension module in a modular PKS has the potential to catalyse iterative rounds of chain elongation like other type I FAS and PKS systems. The factors governing the extent of such 'stuttering' remain to be determined.

A new integrative vector (pCJR24) was constructed for use in the erythromycin producer Saccharopolyspora erythraea and in other actinomycetes. It includes the pathway-specific activator gene actII-ORF4 from the actinorhodin biosynthetic gene cluster of Streptomyces coelicolor. The actI promoter and the associated ribosome binding site are located upstream of an NdeI site (5'-CATATG-3') which encompasses the actI start codon allowing protein(s) to be produced at high levels in response to nutritional signals if these signals are faithfully mediated by the ActII-ORF4 activator. Several polyketide synthase genes were cloned in pCJR24 and overexpressed in S. erythraea after integration of the vector into the chromosome by homologous recombination, indicating the possibility that the S. coelicolor promoter/activator functions appropriately in S. erythraea. pCJR24-mediated recombination was also used to place the entire gene set for the erythromycin-producing polyketide synthase under the control of the actI promoter. The resulting strain produced copious quantities of erythromycins and precursor macrolides when compared with wild-type S. erythraea. The use of this system provides the means for rational strain improvement of antibiotic-producing actinomycetes.

Background: Penicillins and cephalosporins constitute a major class of clinically useful antibiotics. A key step in their biosynthesis involves the oxidative cyclisation of delta-(Lalpha-aminoadipoyl)-L-cysteinyl-D-valine to isopenicillin N by isopenicillin N synthase (IPNS). This chemically remarkable transformation has been extensively studied using substrate analogues. The conversion of an analogue in which the valine is replaced by alpha-aminobutyrate results in three products, two epimeric penams and a cepham. The ratio of these products in reactions catalysed by four different IPNS isozymes has been used previously to probe the thermicity of the chemical mechanism. But how IPNS restricts the products from the natural substrate to a single penam (isopenicillin N) has remained unknown., Results: A key active-site residue, Leu223, identified according to a model of enzyme-substrate binding, has been altered to sterically less demanding residues. As the steric constraints on the upper part of the active site are reduced, the ratio of the beta-methyl penam to the cepham increases when the alpha-aminobutyrate-containing substrate analogue is used. These results suggest a mechanism for processing of the natural substrate in which IPNS uses steric control to restrict the conformational freedom of an intermediate such that the only product is the penam., Conclusions: Using steric pressure to control conformation, and hence to disfavour reactions leading to alternate products, is probably the result of evolutionary selection for a biologically active product at the expense of biologically inactive byproducts. It is likely that this sort of enzymatic catalysis is used in situations where substrate conversion is highly exothermic and a variety of products are possible.

This paper reports on the substance use of 612 gay and bisexual men who participated in an HIV risk reduction project. Use/non-use, level of substance use, and reported frequency of use prior to sexual activity were examined in relation to number of sexual partners, sexual activities, HIV antibody test seeking behaviour and known HIV status. The use of substances among the study cohort appear to be higher than in a comparable heterosexual male group. An association was found between substance use, and both number of sexual partners and sexual activities. However, no significant difference was found in substance use between men participating in protected versus unprotected anal sex. Similarly, no significant difference was found in the reported frequency of substance use prior to sex by those participating in protected and unprotected anal intercourse. Greater drug use was reported among those who were known to be HIV antibody positive. These findings raise issues for further research. The high use of alcohol and drugs by gay and bisexual men may pose significant health risks for this group of men.

The Talking Sex Project is an HIV risk reduction education project for gay and bisexual men. It was developed to evaluate two types of small discussion groups using a randomized control study design. This paper reports on the baseline measures of knowledge, attitudes and sexual practices. The 612 subjects had a mean age of 32 years, were all English speaking and were relatively highly educated. Bivariate analyses found that younger men, those in a relationship, those reporting bisexual activity and those with higher levels of substance use were significantly more likely to have unprotected anal intercourse. While overall knowledge was not associated with sexual behaviour, a significant relationship was found with knowledge of risk of anal sex. Attitudes, in particular, the belief in the efficacy of condoms and the enjoyment of safer sex were found to have the strongest associations with protected anal intercourse. The paper provides an understanding of some of the factors which may be important to behaviour change and clues for the targeting of programs.

Premenstrual syndrome is a recurrent set of disabling symptoms that occur in a definite relation to the menstrual cycle. Patients chart the severity of symptoms over time during consecutive menstrual cycles while the physician should rule out other possible gynecological and psychiatric disorders. Management is through education, environmental manipulation and symptomatic relief of stressors, using a variety of medications. Often a multidisciplinary approach of family physician, psychiatrist and gynecologist is needed.

Among 44 terminally ill patients, the majority (N = 34) had never wished death to come early. Of the remainder, three were or had been suicidal and seven more had desired early death. All 10 patients who had desired death were found to be suffering from clinical depressive illness. The methodologic difficulties encountered by the authors were the lack of a brief, efficient interview schedule suitable for debilitated patients and criteria for depressive disorder that do not depend on suicidal thoughts or on symptoms that can also be caused by physical disease.

As Consultation-Liaison Services continue to develop and expand in general hospitals, psychiatrists must be aware of pitfalls and pratfalls inherent in dealing with medical colleagues and other allied health professionals, as well as with the patients. Practical considerations in answering consultation requests are discussed with respect to "hidden agendas" of the consultee, role and expectations of the psychiatrist, and problem referrals. It is only through mutual respect and collaboration that Consultation-Liaison Services can truly be effective.

We report the fabrication and operation of an Er(3+)-doped silica single-mode fiber laser operating at 1.55 microm and using a distributed fiber grating to provide feedback. The output bandwidth was measured as 0.04 nm, significantly narrower than the conventional cavity design. The laser had a threshold of 13 mW and a slope efficiency of 5%.