Hypothermia Treatment after Hypoxia-Ischemia in Glutathione Peroxidase-1 Overexpressing Mice.

The developing brain is uniquely susceptible to oxidative stress, and endogenous antioxidant mechanisms are not sufficient to prevent injury from a hypoxic-ischemic challenge. Glutathione peroxidase (GPX1) activity reduces hypoxic-ischemic injury. Therapeutic hypothermia (HT) also reduces hypoxic-ischemic injury, in the rodent and the human brain, but the benefit is limited. Here, we combined GPX1 overexpression with HT in a P9 mouse model of hypoxia-ischemia (HI) to test the effectiveness of both treatments together. Histological analysis showed that wild-type (WT) mice with HT were less injured than WT with normothermia. In the GPX1-tg mice, however, despite a lower median score in the HT-treated mice, there was no significant difference between HT and normothermia. GPX1 protein expression was higher in the cortex of all transgenic groups at 30 min and 24 h, as well as in WT 30 min after HI, with and without HT. GPX1 was higher in the hippocampus of all transgenic groups and WT with HI and normothermia, at 24 h, but not at 30 min. Spectrin 150 was higher in all groups with HI, while spectrin 120 was higher in HI groups only at 24 h. There was reduced ERK1/2 activation in both WT and GPX1-tg HI at 30 min. Thus, with a relatively moderate insult, we see a benefit with cooling in the WT but not the GPX1-tg mouse brain. The fact that we see no benefit with increased GPx1 here in the P9 model (unlike in the P7 model) may indicate that oxidative stress in these older mice is elevated to an extent that increased GPx1 is insufficient for reducing injury. The lack of benefit of overexpressing GPX1 in conjunction with HT after HI indicates that pathways triggered by GPX1 overexpression may interfere with the neuroprotective mechanisms provided by HT.

Chromosomal rearrangements as a source of new gene formation in Drosophila yakuba.

The origins of new genes are among the most fundamental questions in evolutionary biology. Our understanding of the ways that new genetic material appears and how that genetic material shapes population variation remains incomplete. De novo genes and duplicate genes are a key source of new genetic material on which selection acts. To better understand the origins of these new gene sequences, we explored the ways that structural variation might alter expression patterns and form novel transcripts. We provide evidence that chromosomal rearrangements are a source of novel genetic variation that facilitates the formation of de novo exons in Drosophila. We identify 51 cases of de novo exon formation created by chromosomal rearrangements in 14 strains of D. yakuba. These new genes inherit transcription start signals and open reading frames when the 5' end of existing genes are combined with previously untranscribed regions. Such new genes would appear with novel peptide sequences, without the necessity for secondary transitions from non-coding RNA to protein. This mechanism of new peptide formations contrasts with canonical theory of de novo gene progression requiring non-coding intermediaries that must acquire new mutations prior to loss via pseudogenization. Hence, these mutations offer a means to de novo gene creation and protein sequence formation in a single mutational step, answering a long standing open question concerning new gene formation. We further identify gene expression changes to 134 existing genes, indicating that these mutations can alter gene regulation. Population variability for chromosomal rearrangements is considerable, with 2368 rearrangements observed across 14 inbred lines. More rearrangements were identified on the X chromosome than any of the autosomes, suggesting the X is more susceptible to chromosome alterations. Together, these results suggest that chromosomal rearrangements are a source of variation in populations that is likely to be important to explain genetic and therefore phenotypic diversity.

Dermatology and Skin Conditions for Hand Surgeons.

The hand surgeon must be familiar with all aspects of hand pathology, and while faced with dermatological pathology in daily practice, a comprehensive understanding of skin pathology is often lacking. Dermatological pathology may have an impact on the hand surgeon in multiple ways-before surgery (requiring optimization), after surgery, or by mimicking surgical pathology (whereby surgical management may be contraindicated). Adequate knowledge of the basics of dermatology allows for optimal patient care. This review article highlights the common (and the not so common) skin conditions that hand surgeons may encounter in their practice.

Histopathological discrepancy between biopsy and Mohs micrographic surgery in keratinocyte carcinoma: A 464 case series in an Australian population.

BACKGROUND/OBJECTIVES: Therapeutic approaches to keratinocyte carcinoma rely on the accuracy of the biopsy to correctly identify, grade or subtype the tumour. Several studies have investigated the frequency and nature of histopathological discordance between the biopsy and final excision specimen. We analysed information extracted from an Australian Mohs micrographic surgery (MMS) database and compared similar studies. METHODS: An Australian MMS database was retrospectively reviewed for a period of one year. Correlation was made between the preoperative lesion diagnosis based on the formal pathology report and the histopathological results reported at the time of MMS. A systematic PubMed review of similar articles was also performed. RESULTS: A total of 464 cancers (406 BCC and 58 SCC) in 399 patients were included. The overall discrepancy rate in the histopathological classification of keratinocyte carcinoma in our study (42.2%) and the proportion of cases in which the biopsy underestimated the aggressiveness of the tumour (12.9%) were consistent with those found in similar studies. The percentage of biopsies that failed to identify an aggressive BCC subtype (31.6%), and that of biopsy-proven superficial BCC that demonstrated an invasive component in MMS (79.3%), were higher in our study than in comparable studies. The high prevalence of mixed histopathological subtypes, especially amongst BCC with discordant histopathological results, appeared as an important contributing factor. CONCLUSIONS: Despite subtle differences, the results from this Australian study support the results from similar studies and highlight that the biopsy report should be carefully interpreted in combination with the clinical findings.

TDP-43 mediated blood-brain barrier permeability and leukocyte infiltration promote neurodegeneration in a low-grade systemic inflammation mouse model.

BACKGROUND: Neuronal cytoplasmic inclusions containing TAR DNA-binding protein 43 (TDP-43) are a neuropathological feature of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's Disease (AD). Emerging evidence also indicates that systemic inflammation may be a contributor to the pathology progression of these neurodegenerative diseases. METHODS: To investigate the role of systemic inflammation in the progression of neuronal TDP-43 pathology, AAV9 particles driven by the UCHL1 promoter were delivered to the frontal cortex of wild-type aged mice via intracranial injections to overexpress TDP-43 or green fluorescent protein (GFP) in corticospinal motor neurons. Animals were then subjected to a low-dose (500 µg/kg) intraperitoneal E. coli lipopolysaccharide (LPS) administration challenge for 2 weeks to mimic a chronically altered low-grade systemic inflammatory state. Mice were then subjected to neurobehavioral studies, followed by biochemical and immunohistochemical analyses of the brain tissue. RESULTS: In the present study, we report that elevated neuronal TDP-43 levels induced microglial and astrocytic activation in the cortex of injected mice followed by increased RANTES signaling. Moreover, overexpression of TDP-43 exerted abundant mouse immunoglobulin G (IgG), CD3, and CD4+ T cell infiltration as well as endothelial and pericyte activation suggesting increased blood-brain barrier permeability. The BBB permeability in TDP-43 overexpressing brains yielded the frontal cortex vulnerable to the systemic inflammatory response following LPS treatment, leading to marked neutrophil infiltration, neuronal loss, reduced synaptosome-associated protein 25 (SNAP-25) levels, and behavioral impairments in the radial arm water maze (RAWM) task. CONCLUSIONS: These results reveal a novel role for TDP-43 in BBB permeability and leukocyte recruitment, indicating complex intermolecular interactions between an altered systemic inflammatory state and pathologically prone TDP-43 protein to promote disease progression.

Role of colour-Doppler high-frequency ultrasonography in capillary malformation-arteriovenous malformation syndrome: a case series.

High-frequency ultrasonography (HFUS) represents a useful adjunct for dermatologists in the diagnosis of capillary malformation-arteriovenous malformation (CM-AVM) syndrome. We present a paediatric case series of 6 patients with confirmed RASA1 gene mutation in whom HFUS demonstrated AVM beneath cutaneous CM-like lesions greater than 1.5 cm.

Movement artifacts in pediatric cutaneous ultrasonography.

BACKGROUND: Cutaneous ultrasonography can be challenging in children. We aim to identify the most complicated cases and the best timing for assessment. METHODS: We retrospectively reviewed sonographic exams in pediatric patients from our cutaneous ultrasonography clinic over a two-year period. Movement artifacts were classified according to their consequences and their frequency was studied in relation to the age of the patient, location of the lesion, and underlying pathology. RESULTS: The overall frequency of exams affected by movement artifacts was 16.76% (91/543) and all belonged to children younger than 4 years of age. The frequency of impaired sonographies was particularly low in patients aged 0 to 4 months (12.77%; 6/47) and particularly high in children aged from 4 to 12 months (56.60%; 60/106). Regarding location, exams were more frequently disadvantaged when assessing the head and neck area (44.53%; 61/137). In relation to pathology, developmental anomalies showed a significantly higher frequency of exams damaged by movement artifacts (41.82%; 23/55). CONCLUSIONS: Cutaneous ultrasonography without sedation can be particularly difficult in children aged between 4 and 12 months, especially when lesions are located on the head and neck and a Doppler exam is required. When assessing congenital lesions, the first four months of life are ideal for a first examination.

Endothelin-a receptor antagonism after renal angioplasty enhances renal recovery in renovascular disease.

Percutaneous transluminal renal angioplasty/stenting (PTRAS) is frequently used to treat renal artery stenosis and renovascular disease (RVD); however, renal function is restored in less than one half of the cases. This study was designed to test a novel intervention that could refine PTRAS and enhance renal recovery in RVD. Renal function was quantified in pigs after 6 weeks of chronic RVD (induced by unilateral renal artery stenosis), established renal damage, and hypertension. Pigs with RVD then underwent PTRAS and were randomized into three groups: placebo (RVD+PTRAS), chronic endothelin-A receptor (ET-A) blockade (RVD+PTRAS+ET-A), and chronic dual ET-A/B blockade (RVD+PTRAS+ET-A/B) for 4 weeks. Renal function was again evaluated after treatments, and then, ex vivo studies were performed on the stented kidney. PTRAS resolved renal stenosis, attenuated hypertension, and improved renal function but did not resolve renal microvascular rarefaction, remodeling, or renal fibrosis. ET-A blocker therapy after PTRAS significantly improved hypertension, microvascular rarefaction, and renal injury and led to greater recovery of renal function. Conversely, combined ET-A/B blockade therapy blunted the therapeutic effects of PTRAS alone or PTRAS followed by ET-A blockade. These data suggest that ET-A receptor blockade therapy could serve as a coadjuvant intervention to enhance the outcomes of PTRAS in RVD. These results also suggest that ET-B receptors are important for renal function in RVD and may contribute to recovery after PTRAS. Using clinically available compounds and techniques, our results could contribute to both refinement and design of new therapeutic strategies in chronic RVD.

Assessment of serum biomarkers in rats after exposure to pesticides of different chemical classes.

There is increasing emphasis on the use of biomarkers of adverse outcomes in safety assessment and translational research. We evaluated serum biomarkers and targeted metabolite profiles after exposure to pesticides (permethrin, deltamethrin, imidacloprid, carbaryl, triadimefon, fipronil) with different neurotoxic actions. Adult male Long-Evans rats were evaluated after single exposure to vehicle or one of two doses of each pesticide at the time of peak effect. The doses were selected to produce similar magnitude of behavioral effects across chemicals. Serum or plasma was analyzed using commercial cytokine/protein panels and targeted metabolomics. Additional studies of fipronil used lower doses (lacking behavioral effects), singly or for 14 days, and included additional markers of exposure and biological activity. Biomarker profiles varied in the number of altered analytes and patterns of change across pesticide classes, and discriminant analysis could separate treatment groups from control. Low doses of fipronil produced greater effects when given for 14 days compared to a single dose. Changes in thyroid hormones and relative amounts of fipronil and its sulfone metabolite also differed between the dosing regimens. Most cytokine changes reflected alterations in inflammatory responses, hormone levels, and products of phospholipid, fatty acid, and amino acid metabolism. These findings demonstrate distinct blood-based analyte profiles across pesticide classes, dose levels, and exposure duration. These results show promise for detailed analyses of these biomarkers and their linkages to biological pathways.

Chronic blockade of endothelin A and B receptors using macitentan in experimental renovascular disease.

BACKGROUND: Emerging research has identified the endothelin (ET)-1 pathway as a potential target for novel renoprotective therapies. We recently showed that selective ET-A receptor antagonism in chronic renovascular disease (RVD) improves renal function and reduces renal injury. Although ET-A and -B have opposing roles, in some clinical situations they may induce similar effects. Thus, we hypothesized that simultaneous blockade of the ET-A and -B receptors would protect the kidney during RVD. METHODS: Unilateral RVD was induced in pigs. After 6 weeks, single-kidney function was quantified in vivo using multi-detector computer tomography. Pigs were subsequently divided into untreated (RVD, n = 7) or daily-treated with the dual ET-A/B receptor antagonist macitentan (RVD + macitentan, n = 6) for 4 weeks. At 10 weeks, in vivo studies were repeated, then pigs were euthanized and ex vivo studies performed in the stenotic kidney to quantify inflammation, fibrosis, microvascular density and remodeling. RESULTS: Four weeks of macitentan therapy modestly improved renal blood flow (29%, P = 0.06 versus pre-treatment) and showed protective effects on the renal parenchyma by attenuating inflammation and glomerulosclerosis, reducing apoptosis and tubular casts and improving albuminuria and cortical microvessel density. No overt adverse effects were observed. CONCLUSION: Possibly by inducing a pro-survival renal microenvironment, macitentan increased renal microvascular density, promoted cell survival and decreased injury, which in turn improved stenotic kidney hemodynamics in our model. Our results further support the safety of using macitentan in patients with concomitant chronic renal disease and supported the feasibility of a new strategy that may preserve the stenotic kidney in RVD.

Cutaneous embolism of an atrial myxoma.

Cardiac myxoma often presents with heterogeneous symptoms and signs and represents a challenging diagnosis. The cutaneous manifestations, if present, are often transient and non-specific and the clinician must possess a high degree of suspicion to secure the diagnosis. We present the case of a 36-year-old woman with a 6-month history of intermittent, painful, violaceous, non-blanching macules on the thumb and fingertips of the left hand and right ankle. A cutaneous embolic phenomenon was suspected and an urgent echocardiogram demonstrated an atrial mass, with subsequent histopathology confirming the clinical suspicion of atrial myxoma. Early diagnosis and excision of the tumour avoided serious complications.

Disparate effects of single endothelin-A and -B receptor blocker therapy on the progression of renal injury in advanced renovascular disease.

We hypothesized that chronic specific endothelin-A (ET-A) receptor blockade therapy would reverse renal dysfunction and injury in advanced experimental renovascular disease. To test this, unilateral renovascular disease was induced in 19 pigs, and after 6 weeks, single-kidney hemodynamics and function was quantified in vivo using computed tomography. All pigs with renovascular disease were divided such that seven were untreated, seven were treated with ET-A blockers, and five were treated with ET-B blockers. Four weeks later, all pigs were restudied in vivo, and then killed and ex vivo studies performed on the stenotic kidney to quantify microvascular density, remodeling, renal oxidative stress, inflammation, and fibrosis. Renal blood flow, glomerular filtration rate, and redox status were significantly improved in the stenotic kidney after ET-A but not ET-B blockade. Furthermore, only ET-A blockade therapy reversed renal microvascular rarefaction and diminished remodeling, which was accompanied by a marked decreased in renal inflammatory and fibrogenic activity. Thus, ET-A but not ET-B blockade ameliorated renal injury in pigs with advanced renovascular disease by stimulating microvascular proliferation and decreasing the progression of microvascular remodeling, renal inflammation, and fibrosis in the stenotic kidney. These effects were functionally consequential as ET-A blockade improved single kidney microvascular endothelial function, renal blood flow, and glomerular filtration rate, and decreased albuminuria.

Renoprotective effects of hepatocyte growth factor in the stenotic kidney.

Renal microvascular (MV) damage and loss contribute to the progression of renal injury in renal artery stenosis (RAS). Hepatocyte growth factor (HGF) is a powerful angiogenic and antifibrotic cytokine that we showed to be decreased in the stenotic kidney. We hypothesized that renal HGF therapy will improve renal function mainly by protecting the renal microcirculation. Unilateral RAS was induced in 15 pigs. Six weeks later, single-kidney RBF and GFR were quantified in vivo using multidetector computed tomography (CT). Then, intrarenal rh-HGF or vehicle was randomly administered into the stenotic kidney (RAS, n = 8; RAS+HGF, n = 7). Pigs were observed for 4 additional weeks before CT studies were repeated. Renal MV density was quantified by 3D micro-CT ex vivo and histology, and expression of angiogenic and inflammatory factors, apoptosis, and fibrosis was determined. HGF therapy improved RBF and GFR compared with vehicle-treated pigs. This was accompanied by improved renal expression of angiogenic cytokines (VEGF, p-Akt) and tissue-healing promoters (SDF-1, CXCR4, MMP-9), reduced MV remodeling, apoptosis, and fibrosis, and attenuated renal inflammation. However, HGF therapy did not improve renal MV density, which was similarly reduced in RAS and RAS+HGF compared with controls. Using a clinically relevant animal model of RAS, we showed novel therapeutic effects of a targeted renal intervention. Our results show distinct actions on the existing renal microcirculation and promising renoprotective effects of HGF therapy in RAS. Furthermore, these effects imply plasticity of the stenotic kidney to recuperate its function and underscore the importance of MV integrity in the progression of renal injury in RAS.

Lasers and laser-like devices: part one.

Lasers have been used in dermatology for nearly 50 years. Through their selective targeting of skin chromophores they have become the preferred treatment for many skin conditions, including vascular malformations, photorejuvenation and acne scars. The technology and design of lasers continue to evolve, allowing greater control of laser parameters and resulting in increased safety and efficacy for patients. Innovations have allowed the range of conditions and the skin types amenable to treatment, in both general and cosmetic dermatology, to expand over the last decade. Integrated skin cooling and laser beam fractionation, for example, have improved safety, patient tolerance and decreased downtime. Furthermore, the availability and affordability of quality devices continues to increase, allowing clinicians not only to access laser therapies more readily but also to develop their personal experience in this field. As a result, most Australian dermatologists now have access to laser therapies, either in their own practice or within referable proximity, and practical knowledge of these technologies is increasingly required and expected by patients. Non-laser energy devices utilising intense pulsed light, plasma, radiofrequency, ultrasound and cryolipolysis contribute to the modern laser practitioners' armamentarium and will also be discussed.

A Quality Improvement Project to Gain Insight Into What Helps Cancer Patients Cope During Outpatient Radiation Therapy Treatments.

Psychosocial support in cancer care has not been researched or published to the degree of physical support. This type of support includes the mental, emotional, social, and spiritual needs of patients and loved ones. This quality improvement project provides insight for those seeking understanding of what exactly helps cancer patients cope during outpatient radiation therapy treatments. The purpose of this project was to learn what practices benefit patient's coping during outpatient external radiation therapy treatments in order to increase attention given to psychosocial support of future cancer patients receiving outpatient external radiation therapy treatments. Insight from this project was used to create a resource handout for Novant Health Cancer Institute to help increase awareness, discussion, and attention to supporting outpatient radiation therapy patients emotionally and spiritually.

Acute-Onset Multifocal Hand Dysfunction Due to Alkaptonuria.

Alkaptonuria is a rare metabolic disorder characterized by the accumulation of homogentisic acid. Its effects on the central nervous system are well-recognized; however, cases of pathologic homogentisic acid deposition in the peripheral nervous system are less well-described. We report the case of a 72-year-old man with a prior history of alkaptonuria presenting with bilateral carpal tunnel and left-sided cubital tunnel symptoms. This case is of note because the patient demonstrated a rapid onset of symptoms due to pathology at multiple foci.

A quality improvement project to standardize chaplain documentation in the electronic medical record.

Medical record documentation by hospital chaplains is an under-researched and under-published field. Because documentation serves both as a register of chaplain interventions and as a collaborative tool for interdisciplinary communication, it should be written in a way that is clear, concise, and consistent. As chaplains continue to integrate with other medical professions in interdisciplinary care, careful attention should be given to the way in which communication of the chaplain role, functioning, and patient information obtained is conveyed. This quality improvement project standardized chaplain documentation in one health system of 15 medical centers, provides insights and resources devised from the project, and offers considerations for other systems contemplating future changes toward standardizing documentation.