Stomatin is highly expressed in exosomes of different origin and is a promising candidate as an exosomal marker

Proteins involved in the organizing of lipid rafts can be found in exosomes, as shown for caveolin‐1, and they could contribute to exosomal cargo sorting, as shown for flotillins. Stomatin belongs to the same stomatin/prohibitin/flotillin/HflK/C family of lipid rafts proteins, but it has never been studied in exosomes except for extracellular vesicles (EVs) originating from blood cells. Here we first show the presence of stomatin in exosomes produced by epithelial cancer cells (non–small cell lung cancer, breast, and ovarian cancer cells) as well as in EVs from biological fluids, including blood plasma, ascitic fluids, and uterine flushings. A high abundance of stomatin in EVs of various origins and its enrichment in exosomes make stomatin a promising exosomal marker. Comparison with other lipid raft proteins and exosomal markers showed that the level of stomatin protein in exosomes from different sources corresponds well to that of CD9, while it differs essentially from flotillin‐1 and flotillin‐2 homologs, which in turn are present in exosomes in nearly equal proportions. In contrast, the level of vesicular caveolin‐1 as well as its EV‐to‐cellular ratio vary drastically depending on cell type.     

Determination of relative age using growth increments of scales as a minimally invasive method in the tropical freshwater Apteronotus leptorhynchus

This study describes a method for the determination of relative age in a tropical teleost, the brown ghost knifefish Apteronotus leptorhynchus. This method is based on identification of the maximum number of scale circuli, which is thought to be associated with the oldest scales, and thus to be the most indicative of the age of a given fish. Relative age can be inferred by relating differences in maximum circulus counts to the average rate of circulus addition, which was estimated at 34 circuli per year in adult fish through oxytetracycline marking. This method shows high inter‐investigator reliability and has a limited effect on fish because of the low number of scales required in order to determine the maximum number of circuli with a sufficiently high confidence level. Analysis of the frequency distribution of the circulus counts revealed periodic patterns that are similar among fish, presumably reflecting the environmental life history of the individuals. Regression analysis and comparison of addition rates showed that scale circulus counts and otolith ring counts are equivalent approaches for age estimation, but scale analysis is superior because of its limited invasiveness and the lower demand in terms of technical skills and expensive instrumentation.     

Suicidality,Bullying and Other Conduct and Mental Health Correlates of Traumatic Brain Injury in Adolescents

Objective

Our knowledge on the adverse correlates of traumatic brain injuries (TBI), including non-hospitalized cases, among adolescents is limited to case studies. We report lifetime TBI and adverse mental health and conduct behaviours associated with TBI among adolescents from a population-based sample in Ontario.

Method and Findings

Data were derived from 4,685 surveys administered to adolescents in grades 7 through 12 as part of the 2011 population-based cross-sectional Ontario Student Drug Use and Health Survey (OSDUHS). Lifetime TBI was defined as head injury that resulted in being unconscious for at least 5 minutes or being retained in the hospital for at least one night, and was reported by 19.5% (95%CI:17.3,21.9) of students. When holding constant sex, grade, and complex sample design, students with TBI had significantly greater odds of reporting elevated psychological distress (AOR = 1.52), attempting suicide (AOR = 3.39), seeking counselling through a crisis help-line (AOR = 2.10), and being prescribed medication for anxiety, depression, or both (AOR = 2.45). Moreover, students with TBI had higher odds of being victimized through bullying at school (AOR = 1.70), being cyber-bullied (AOR = 2.05), and being threatened with a weapon at school (AOR = 2.90), compared with students who did not report TBI. Students with TBI also had higher odds of victimizing others and engaging in numerous violent as well as nonviolent conduct behaviours.

Conclusions

Significant associations between TBI and adverse internalizing and externalizing behaviours were found in this large population-based study of adolescents. Those who reported lifetime TBI were at a high risk for experiencing mental and physical health harms in the past year than peers who never had a head injury. Primary physicians should be vigilant and screen for potential mental heath and behavioural harms in adolescent patients with TBI. Efforts to prevent TBI during adolescence and intervene at an early stage may reduce injuries and comorbid problems in this age group.     

MTO1-Deficient Mouse Model Mirrors the Human Phenotype Showing Complex I Defect and Cardiomyopathy

Recently, mutations in the mitochondrial translation optimization factor 1 gene (MTO1) were identified as causative in children with hypertrophic cardiomyopathy, lactic acidosis and respiratory chain defect. Here, we describe an MTO1-deficient mouse model generated by gene trap mutagenesis that mirrors the human phenotype remarkably well. As in patients, the most prominent signs and symptoms were cardiovascular and included bradycardia and cardiomyopathy. In addition, the mutant mice showed a marked worsening of arrhythmias during induction and reversal of anaesthesia. The detailed morphological and biochemical workup of murine hearts indicated that the myocardial damage was due to complex I deficiency and mitochondrial dysfunction. In contrast, neurological examination was largely normal in Mto1-deficient mice. A translational consequence of this mouse model may be to caution against anaesthesia-related cardiac arrhythmias which may be fatal in patients.     

Energy Drinks,Alcohol, Sports and Traumatic Brain Injuries among Adolescents

Importance

The high prevalence of traumatic brain injuries (TBI) among adolescents has brought much focus to this area in recent years. Sports injuries have been identified as a main mechanism. Although energy drinks, including those mixed with alcohol, are often used by young athletes and other adolescents they have not been examined in relation to TBI.

Objective

We report on the prevalence of adolescent TBI and its associations with energy drinks, alcohol and energy drink mixed in with alcohol consumption.

Design, Settings and Participants

Data were derived from the Centre for Addiction and Mental Health’s 2013 Ontario Student Drug Use and Health Survey (OSDUHS). This population-based cross-sectional school survey included 10,272 7^th to 12^th graders (ages 11–20) who completed anonymous self-administered questionnaires in classrooms.

Main Outcome Measures

Mild to severe TBI were defined as those resulting in a loss of consciousness for at least five minutes, or being hospitalized for at least one night. Mechanism of TBI, prevalence estimates of TBI, and odds of energy drink consumption, alcohol use, and consumption of energy drinks mixed with alcohol are assessed.

Results

Among all students, 22.4% (95% CI: 20.7, 24.1) reported a history of TBI. Sports injuries remain the main mechanism of a recent (past year) TBI (45.5%, 95% CI: 41.0, 50.1). Multinomial logistic regression showed that relative to adolescents who never sustained a TBI, the odds of sustaining a recent TBI were greater for those consuming alcohol, energy drinks, and energy drinks mixed in with alcohol than abstainers. Odds ratios were higher for these behaviors among students who sustained a recent TBI than those who sustained a former TBI (lifetime but not past 12 months). Relative to recent TBI due to other causes of injury, adolescents who sustained a recent TBI while playing sports had higher odds of recent energy drinks consumption than abstainers.

Conclusions and Relevance

TBI remains a disabling and common condition among adolescents and the consumption of alcohol, energy drinks, and alcohol mixed with energy drinks further increase the odds of TBI among adolescents. These associations warrant further investigation.     

Defects in innate immunity render breast cancer initiating cells permissive to oncolytic adenovirus

Background

Cancer stem cells/initiating cells (CSC/CIC), are thought to exist as a small population in malignant tissues. They are resistant to conventional cancer treatments and possibly underlie post-treatment relapse. The CIC population can be targeted with capsid modified oncolytic adenoviruses.

Methodology/Principal Findings

We studied the mechanisms of innate immunity to oncolytic adenovirus Ad5/3-Delta24 in conventional treatment resistant non-CIC breast cancer cells, breast cancer CD44⁺/CD24^−/low CIC population and normal breast tissue CD44⁺/CD24^−/low stem cells. We compared virus recognition by pattern recognition receptors for adenovirus, Toll-like receptors (TLR) 2 and 9 and virus induced type I interferon (IFN) response regulation in these cell types. We show TLR mediated virus recognition in these non-immune cell types. Normal tissue stem cells have intact type I IFN signaling. Furthermore, TLR9 and TLR2 reside constantly in recognition sites, implying constant activation. In contrast, breast cancer CD44⁺/CD24^−/low CIC have dysregulated innate immune responses featuring dysfunctional virus recognition caused by impaired trafficking of TLR9 and cofactor MyD88 and the absence of TLR2, having a deleterious impact on TLR pattern recognition receptor signaling. Furthermore, the CIC have increased inhibitory signaling via the suppressor of cytokine signaling/Tyro3/Axl/Mer receptor tyrosine kinase (SOCS/TAM) pathway. These defects in contribute to dysfunctional induction of type I IFN response in CIC and therefore permissivity to oncolytic adenovirus.

Conclusions/Significance

CICs may underlie the incurable nature of relapsed or metastatic cancers and are therefore an important target regarding diagnostic and prognostic aspects as well as treatment of the disease. This study addresses the mechanisms of innate infection immunity in stem cells deepening the understanding of stem cell biology and may benefit not only virotherapy but also immunotherapy in general.     

The genome of the obligate endobacterium of an AM fungus reveals an interphylum network of nutritional interactions

As obligate symbionts of most land plants, arbuscular mycorrhizal fungi (AMF) have a crucial role in ecosystems, but to date, in the absence of genomic data, their adaptive biology remains elusive. In addition, endobacteria are found in their cytoplasm, the role of which is unknown. In order to investigate the function of the Gram-negative Candidatus Glomeribacter gigasporarum, an endobacterium of the AMF Gigaspora margarita, we sequenced its genome, leading to an ∼1.72-Mb assembly. Phylogenetic analyses placed Ca. G. gigasporarum in the Burkholderiaceae whereas metabolic network analyses clustered it with insect endobacteria. This positioning of Ca. G. gigasporarum among different bacterial classes reveals that it has undergone convergent evolution to adapt itself to intracellular lifestyle. The genome annotation of this mycorrhizal-fungal endobacterium has revealed an unexpected genetic mosaic where typical determinants of symbiotic, pathogenic and free-living bacteria are integrated in a reduced genome. Ca. G. gigasporarum is an aerobic microbe that depends on its host for carbon, phosphorus and nitrogen supply; it also expresses type II and type III secretion systems and synthesizes vitamin B12, antibiotics- and toxin-resistance molecules, which may contribute to the fungal host''s ecological fitness. Ca. G. gigasporarum has an extreme dependence on its host for nutrients and energy, whereas the fungal host is itself an obligate biotroph that relies on a photosynthetic plant. Our work represents the first step towards unraveling a complex network of interphylum interactions, which is expected to have a previously unrecognized ecological impact.     

Usefulness of oral cytopathology in the diagnosis of infectious diseases

P. H. Braz‐Silva, M. H. C. G. Magalhães, V. Hofman, K. L. Ortega, M. I. Ilie, G. Odin, P. Vielh and P. Hofman Usefulness of oral cytopathology in the diagnosis of infectious diseases In recent years, the incidence of oral opportunistic infections has increased, partly due to the widespread implementation of organ and bone marrow transplantation and the increase in the prevalence of human immunodeficiency virus (HIV) infection. Cytology can be used as a rapid, inexpensive and simple routine procedure in diagnosing infectious diseases of the mouth. Moreover, ancillary methods can be applied to cytological samples, increasing the specificity and sensitivity for the diagnosis of infectious diseases. This review describes the cytopathological features of the main viral, fungal, bacterial and parasitic infections of the mouth. Cytological techniques of specimen collection, identification of infectious agents by cytomorphological approaches and ancillary methods, and diagnostic pitfalls will be discussed.     

Towards the Development of Hemerythrin-Based Blood Substitutes

Hemerythrin is proposed as an alternative to hemoglobin-based blood substitutes. In contrast to hemoglobin, hemerythrin exhibits negligible reactivity towards oxidative and nitrosative stress agents (peroxide, nitric oxide, nitrite). Protocols for attachment of polyethylene glycol and glutaraldehyde cross-linking of Hr are described. These derivatizations appear to have favorable effects on O₂ affinity and autoxidation rates for use in blood substitutes. Based on lessons learned from hemoglobin-based blood substitutes, these derivatizations should also help limit extravasation and antigenicity of a hemerythrin-based blood substitute.     

Rhodium(II)-catalyzed decomposition of 3-O-(2-diazo-2-phenylacetyl)-1,2;5,6-di-O-isopropylidene-alpha-D-allofuranose: diastereoselective ether formation

Standard diazo transfer to 3-O-(2-phenylacetyl)-1,2;5,6-di-O-isopropylidene-alpha-d-allofuranose (2), using p-acetamidobenzenesulfonyl azide (p-ABSA, 3) and DBU as base, provides the expected 3-O-(2-diazo-2-phenylacetyl)-1,2;5,6-di-O-isopropylidene-alpha-D-allofuranose (4) as an orange syrup in 49% isolated yield. Subsequent decomposition of 4 using Rh(2)(OAc)(4) yields ether 5 in a highly diastereoselective manner and in 58% isolated yield. The X-ray crystal structure of 5 proves that both newly produced stereocenters have the (S) configuration; the conformation of the ester group at O-3 of the furanose ring of 5 is used to discuss the possible cause of the observed stereoselectivity.