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1.
J STEM Outreach ; 7(2)2024 Feb.
Article in English | MEDLINE | ID: mdl-39006760

ABSTRACT

As federal strategic plans prioritize increasing diversity within the biomedical workforce, and STEM training and outreach programs seek to recruit and retain students from historically underrepresented populations, there is a need for interrogation of traditional demographic descriptors and careful consideration of best practices for obtaining demographic data. To accelerate this work, equity-focused researchers and leaders from STEM programs convened to examine approaches for measuring demographic variables. Gender, race/ethnicity, disability, and disadvantaged background were prioritized given their focus by federal funding agencies. Categories of sex minority, sexual (orientation) minority, and gender minority (SSGM) should be included in demographic measures collected by STEM programs, consistent with recommendations from White House Executive Orders and federal reports. Our manuscript offers operationalized phrasing for demographic questions and recommendations for use across student-serving programs. Inclusive demographics permit the identification of individuals who are being excluded, marginalized, or improperly aggregated, increasing capacity to address inequities in biomedical research training. As trainees do not enter training programs with equal access, accommodations, or preparation, inclusive demographic measures can welcome trainees and inform a nuanced set of program outcomes that facilitate research on intersectionality to support the recruitment and retention of underrepresented students in biomedical research.

2.
Front Physiol ; 15: 1348395, 2024.
Article in English | MEDLINE | ID: mdl-38370016

ABSTRACT

Biological magnetic field sensing that gives rise to physiological responses is of considerable importance in quantum biology. The radical pair mechanism (RPM) is a fundamental quantum process that can explain some of the observed biological magnetic effects. In magnetically sensitive radical pair (RP) reactions, coherent spin dynamics between singlet and triplet pairs are modulated by weak magnetic fields. The resulting singlet and triplet reaction products lead to distinct biological signaling channels and cellular outcomes. A prevalent RP in biology is between flavin semiquinone and superoxide (O2 •-) in the biological activation of molecular oxygen. This RP can result in a partitioning of reactive oxygen species (ROS) products to form either O2 •- or hydrogen peroxide (H2O2). Here, we examine magnetic sensing of recombinant human electron transfer flavoenzyme (ETF) reoxidation by selectively measuring O2 •- and H2O2 product distributions. ROS partitioning was observed between two static magnetic fields at 20 nT and 50 µT, with a 13% decrease in H2O2 singlet products and a 10% increase in O2 •- triplet products relative to 50 µT. RPM product yields were calculated for a realistic flavin/superoxide RP across the range of static magnetic fields, in agreement with experimental results. For a triplet born RP, the RPM also predicts about three times more O2 •- than H2O2, with experimental results exhibiting about four time more O2 •- produced by ETF. The method presented here illustrates the potential of a novel magnetic flavoprotein biological sensor that is directly linked to mitochondria bioenergetics and can be used as a target to study cell physiology.

3.
Sci Adv ; 9(46): eadj2832, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37976350

ABSTRACT

Organic aerosol (OA) is an air pollutant ubiquitous in urban atmospheres. Urban OA is usually apportioned into primary OA (POA), mostly emitted by mobile sources, and secondary OA (SOA), which forms in the atmosphere due to oxidation of gas-phase precursors from anthropogenic and biogenic sources. By performing coordinated measurements in the particle phase and the gas phase, we show that the alkylperoxy radical chemistry that is responsible for low-temperature ignition also leads to the formation of oxygenated POA (OxyPOA). OxyPOA is distinct from POA emitted during high-temperature ignition and is chemically similar to SOA. We present evidence for the prevalence of OxyPOA in emissions of a spark-ignition engine and a next-generation advanced compression-ignition engine, highlighting the importance of understanding OxyPOA for predicting urban air pollution patterns in current and future atmospheres.

4.
Metabolites ; 13(2)2023 Feb 07.
Article in English | MEDLINE | ID: mdl-36837861

ABSTRACT

Limited data are available on the effects of pregnancy on the maternal metabolome. Therefore, the objective of this study was to use metabolomics analysis to determine pathways impacted by pregnancy followed by targeted confirmatory analysis to provide more powerful conclusions about metabolic alterations during pregnancy. Forty-seven pregnant women, 18-50 years of age were included in this study, with each subject serving as their own control. Plasma samples were collected between 25 and 28 weeks gestation and again ≥3 months postpartum for metabolomics analysis utilizing an HILIC/UHPLC/MS/MS assay with confirmatory targeted specific concentration analysis for 10 of the significantly altered amino acids utilizing an LC/MS assay. Principle component analysis (PCA) on metabolomics data clearly separated pregnant and postpartum groups and identified outliers in a preliminary assessment. Of the 980 metabolites recorded, 706 were determined to be significantly different between pregnancy and postpartum. Pathway analysis revealed three significantly impacted pathways, arginine biosynthesis (p = 2 × 10-5 and FDR = 1 × 10-3), valine, leucine, and isoleucine metabolism (p = 2 × 10-5 and FDR = 2 × 10-3), and xanthine metabolism (p = 4 × 10-5 and FDR = 4 × 10-3). Of these we focused analysis on arginine biosynthesis and branched-chain amino acid (BCAA) metabolism due to their clinical importance and interconnected roles in amino acid metabolism. In the confirmational analysis, 7 of 10 metabolites were confirmed as significant and all 10 confirmed the direction of change of concentrations observed in the metabolomics analysis. The data support an alteration in urea nitrogen disposition and amino acid metabolism during pregnancy. These changes could also impact endogenous nitric oxide production and contribute to diseases of pregnancy. This study provides evidence for changes in both the ammonia-urea nitrogen and the BCAA metabolism taking place during pregnancy.

5.
Osteoarthritis Cartilage ; 30(9): 1244-1253, 2022 09.
Article in English | MEDLINE | ID: mdl-35644462

ABSTRACT

OBJECTIVE: To determine if the quantitative MRI techniques T2 and T1ρ mapping are sensitive to ischemic injury to epiphyseal cartilage in vivo in a piglet model of Legg-Calvé-Perthes disease using a clinical 3T MRI scanner. We hypothesized that T2 and T1ρ relaxation times would be increased in the epiphyseal cartilage of operated vs contralateral-control femoral heads 1 week following onset of ischemia. DESIGN: Unilateral femoral head ischemia was surgically induced in eight piglets. Piglets were imaged 1 week post-operatively in vivo at 3T MRI using a magnetization-prepared 3D fast spin echo sequence for T2 and T1ρ mapping and a 3D gradient echo sequence for cartilage segmentation. Ischemia was confirmed in all piglets using gadolinium contrast-enhanced MRI. Median T2 and T1ρ relaxation times were measured in the epiphyseal cartilage of the ischemic and control femoral heads and compared using paired t-tests. Histological assessment was performed on a subset of five piglets. RESULTS: T2 and T1ρ relaxation times were significantly increased in the epiphyseal cartilage of the operated vs control femoral heads (ΔT2 = 11.9 ± 3.7 ms, 95% CI = [8.8, 15.0] ms, P < 0.0001; ΔT1ρ = 12.8 ± 4.1 ms, 95% CI = [9.4, 16.2] ms, P < 0.0001). Histological assessment identified chondronecrosis in the hypertrophic and deep proliferative zones within ischemic epiphyseal cartilage. CONCLUSIONS: T2 and T1ρ mapping are sensitive to ischemic injury to the epiphyseal cartilage in vivo at clinical 3T MRI. These techniques may be clinically useful to assess injury and repair to the epiphyseal cartilage to better stage the extent of ischemic damage in Legg-Calvé-Perthes disease.


Subject(s)
Cartilage, Articular , Legg-Calve-Perthes Disease , Animals , Cartilage/pathology , Cartilage, Articular/diagnostic imaging , Cartilage, Articular/pathology , Femur Head/diagnostic imaging , Femur Head/pathology , Growth Plate/diagnostic imaging , Growth Plate/pathology , Ischemia/diagnostic imaging , Ischemia/etiology , Legg-Calve-Perthes Disease/diagnostic imaging , Legg-Calve-Perthes Disease/pathology , Magnetic Resonance Imaging/methods , Swine
6.
Nutrients ; 14(7)2022 Mar 25.
Article in English | MEDLINE | ID: mdl-35405978

ABSTRACT

Vitamin A is vital to maternal-fetal health and pregnancy outcomes. However, little is known about pregnancy associated changes in maternal vitamin A homeostasis and concentrations of circulating retinol metabolites. The goal of this study was to characterize retinoid concentrations in healthy women (n = 23) during two stages of pregnancy (25-28 weeks gestation and 28-32 weeks gestation) as compared to ≥3 months postpartum. It was hypothesized that plasma retinol, retinol binding protein 4 (RBP4), transthyretin and albumin concentrations would decline during pregnancy and return to baseline by 3 months postpartum. At 25-28 weeks gestation, plasma retinol (-27%), 4-oxo-13-cis-retinoic acid (-34%), and albumin (-22%) concentrations were significantly lower, and all-trans-retinoic acid (+48%) concentrations were significantly higher compared to ≥3 months postpartum in healthy women. In addition, at 28-32 weeks gestation, plasma retinol (-41%), retinol binding protein 4 (RBP4; -17%), transthyretin (TTR; -21%), albumin (-26%), 13-cis-retinoic acid (-23%) and 4-oxo-13-cis-retinoic acid (-48%) concentrations were significantly lower, whereas plasma all-trans-retinoic acid concentrations (+30%) were significantly higher than ≥3 months postpartum. Collectively, the data demonstrates that in healthy pregnancies, retinol plasma concentrations are lower, but all-trans-retinoic acid concentrations are higher than postpartum.


Subject(s)
Prealbumin , Vitamin A , Female , Humans , Prealbumin/metabolism , Pregnancy , Pregnant Women , Retinoids , Retinol-Binding Proteins, Plasma/metabolism , Tretinoin/metabolism
7.
Cancer Discov ; 11(8): 2072-2093, 2021 08.
Article in English | MEDLINE | ID: mdl-33757970

ABSTRACT

Clear cell renal cell carcinoma (ccRCC) is characterized by accumulation of neutral lipids and adipogenic transdifferentiation. We assessed adipokine expression in ccRCC and found that tumor tissues and patient plasma exhibit obesity-dependent elevations of the adipokine chemerin. Attenuation of chemerin by several approaches led to significant reduction in lipid deposition and impairment of tumor cell growth in vitro and in vivo. A multi-omics approach revealed that chemerin suppresses fatty acid oxidation, preventing ferroptosis, and maintains fatty acid levels that activate hypoxia-inducible factor 2α expression. The lipid coenzyme Q and mitochondrial complex IV, whose biogeneses are lipid-dependent, were found to be decreased after chemerin inhibition, contributing to lipid reactive oxygen species production. Monoclonal antibody targeting chemerin led to reduced lipid storage and diminished tumor growth, demonstrating translational potential of chemerin inhibition. Collectively, the results suggest that obesity and tumor cells contribute to ccRCC through the expression of chemerin, which is indispensable in ccRCC biology. SIGNIFICANCE: Identification of a hypoxia-inducible factor-dependent adipokine that prevents fatty acid oxidation and causes escape from ferroptosis highlights a critical metabolic dependency unique in the clear cell subtype of kidney cancer. Targeting lipid metabolism via inhibition of a soluble factor is a promising pharmacologic approach to expand therapeutic strategies for patients with ccRCC.See related commentary by Reznik et al., p. 1879.This article is highlighted in the In This Issue feature, p. 1861.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Carcinoma, Renal Cell/drug therapy , Kidney Neoplasms/drug therapy , Obesity/complications , Animals , Carcinoma, Renal Cell/complications , Cell Line, Tumor/drug effects , Fatty Acids/metabolism , Female , Ferroptosis/drug effects , Humans , Kidney Neoplasms/complications , Lipid Metabolism/drug effects , Mice , Mice, Nude
8.
Mol Metab ; 34: 136-145, 2020 04.
Article in English | MEDLINE | ID: mdl-32180553

ABSTRACT

OBJECTIVE: The most common kidney cancer, clear cell renal cell carcinoma (ccRCC), is closely associated with obesity. The "clear cell" variant of RCC gets its name from the large lipid droplets that accumulate in the tumor cells. Although renal lipid metabolism is altered in ccRCC, the mechanisms and lipids driving this are not well understood. METHODS: We used shotgun lipidomics in human ccRCC tumors and matched normal adjacent renal tissue. To assess MBOAT7s gene expression across tumor severity, we examined histologically graded human ccRCC samples. We then utilized genome editing in ccRCC cell lines to understand the role of MBOAT7 in ccRCC progression. RESULTS: We identified a lipid signature for ccRCC that includes an increase in arachidonic acid-enriched phosphatidylinositols (AA-PI). In parallel, we found that ccRCC tumors have increased expression of acyltransferase enzyme membrane bound O-acyltransferase domain containing 7 (MBOAT7) that contributes to AA-PI synthesis. In ccRCC patients, MBOAT7 expression increases with tumor grade, and increased MBOAT7 expression correlates with poor survival. Genetic deletion of MBOAT7 in ccRCC cells decreases proliferation and induces cell cycle arrest, and MBOAT7-/- cells fail to form tumors in vivo. RNAseq of MBOAT7-/- cells identified alterations in cell migration and extracellular matrix organization that were functionally validated in migration assays. CONCLUSIONS: This study highlights the accumulation of AA-PI in ccRCC and demonstrates a novel way to decrease the AA-PI pool in ccRCC by limiting MBOAT7. Our data reveal that metastatic ccRCC is associated with altered AA-PI metabolism and identify MBOAT7 as a novel target in advanced ccRCC.


Subject(s)
Acyltransferases/metabolism , Carcinoma, Renal Cell/metabolism , Kidney Neoplasms/metabolism , Membrane Proteins/metabolism , Phosphatidylinositols/metabolism , Acyltransferases/deficiency , Carcinoma, Renal Cell/pathology , Humans , Kidney Neoplasms/pathology , Membrane Proteins/deficiency , Tumor Cells, Cultured
9.
J Nutr ; 150(4): 775-783, 2020 04 01.
Article in English | MEDLINE | ID: mdl-31851339

ABSTRACT

BACKGROUND: Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death in the world. Choline deficiency has been well studied in the context of liver disease; however, less is known about the effects of choline supplementation in HCC. OBJECTIVE: The objective of this study was to test whether choline supplementation could influence the progression of HCC in a high-fat-diet (HFD)-driven mouse model. METHODS: Four-day-old male C57BL/6J mice were treated with the chemical carcinogen, 7,12-dimethylbenz[a]anthracene, and were randomly assigned at weaning to a cohort fed an HFD (60% kcal fat) or an HFD with supplemental choline (60% kcal fat, 1.2% choline; HFD+C) for 30 wk. Blood was isolated at 15 and 30 wk to measure immune cells by flow cytometry, and glucose-tolerance tests were performed 2 wk prior to killing. Overall tumor burden was quantified, hepatic lipids were measured enzymatically, and phosphatidylcholine species were measured by targeted MS methods. Gene expression and mitochondrial DNA were quantified by quantitative PCR. RESULTS: HFD+C mice exhibited a 50-90% increase in both circulating choline and betaine concentrations in the fed state (P ≤ 0.05). Choline supplementation resulted in a 55% decrease in total tumor numbers, a 67% decrease in tumor surface area, and a 50% decrease in hepatic steatosis after 30 wk of diet (P ≤ 0.05). Choline supplementation increased the abundance of mitochondria and the relative expression of ß-oxidation genes by 21% and ∼75-100%, respectively, in the liver. HFD+C attenuated circulating myeloid-derived suppressor cells at 15 wk of feeding (P ≤ 0.05). CONCLUSIONS: Choline supplementation attenuated HFD-induced HCC and hepatic steatosis in male C57BL/6J mice. These results suggest a therapeutic benefit of choline supplementation in blunting HCC progression.


Subject(s)
Choline/administration & dosage , Diet, High-Fat/adverse effects , Liver Neoplasms, Experimental/prevention & control , Liver Neoplasms/prevention & control , Animals , Betaine/blood , Choline/blood , DNA, Mitochondrial/analysis , Dietary Supplements , Fatty Liver/prevention & control , Gene Expression/drug effects , Lipid Metabolism/genetics , Liver/chemistry , Liver/pathology , Liver Neoplasms/etiology , Liver Neoplasms/pathology , Liver Neoplasms, Experimental/etiology , Liver Neoplasms, Experimental/pathology , Male , Mice , Mice, Inbred C57BL , Myeloid-Derived Suppressor Cells/pathology , Organ Size/drug effects
10.
Elife ; 82019 10 17.
Article in English | MEDLINE | ID: mdl-31621579

ABSTRACT

Recent studies have identified a genetic variant rs641738 near two genes encoding membrane bound O-acyltransferase domain-containing 7 (MBOAT7) and transmembrane channel-like 4 (TMC4) that associate with increased risk of non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), alcohol-related cirrhosis, and liver fibrosis in those infected with viral hepatitis (Buch et al., 2015; Mancina et al., 2016; Luukkonen et al., 2016; Thabet et al., 2016; Viitasalo et al., 2016; Krawczyk et al., 2017; Thabet et al., 2017). Based on hepatic expression quantitative trait loci analysis, it has been suggested that MBOAT7 loss of function promotes liver disease progression (Buch et al., 2015; Mancina et al., 2016; Luukkonen et al., 2016; Thabet et al., 2016; Viitasalo et al., 2016; Krawczyk et al., 2017; Thabet et al., 2017), but this has never been formally tested. Here we show that Mboat7 loss, but not Tmc4, in mice is sufficient to promote the progression of NAFLD in the setting of high fat diet. Mboat7 loss of function is associated with accumulation of its substrate lysophosphatidylinositol (LPI) lipids, and direct administration of LPI promotes hepatic inflammatory and fibrotic transcriptional changes in an Mboat7-dependent manner. These studies reveal a novel role for MBOAT7-driven acylation of LPI lipids in suppressing the progression of NAFLD.


Subject(s)
Acyltransferases/genetics , Membrane Proteins/genetics , Non-alcoholic Fatty Liver Disease/genetics , Obesity/genetics , Acylation , Animals , Disease Progression , Humans , Mice
11.
Clin Exp Immunol ; 196(1): 67-75, 2019 04.
Article in English | MEDLINE | ID: mdl-30714144

ABSTRACT

Epigenetic effects of anti-psychotic medications are poorly understood. We have appropriated a model whereby heterochromatin is established through 24- or 48-h lipopolysaccharide (LPS) treatment, and tested the epigenetic effects of risperidone along the adenylyl cyclase/protein kinase A (AC/PKA) pathway in human liposarcoma cells that express the LPS-sensitive Toll-like receptor (TLR)-4. Human SW872 cells were cultured with LPS and mRNA expression levels and epigenetic modifications of dimethylated lysine 9 of histone 2 (H3K9me2), geterochromatin protein 1γ (HP1γ) and phospho-H3S10 at promoters of interleukin (IL)-6, tumor necrosis factor (TNF)-α and IL1ß were measured. Pharmacological manipulation of the AC/PKA pathway was achieved through treatment with a PKA inhibitor (H89), mitogen- and stress-activated kinase 1 (MSK1) inhibitor (SB-747651A) or forskolin. Twenty-four and 48-h LPS treatment establishes heterochromatin at selected promoters, corresponding to decreased mRNA expression. Concurrent risperidone treatment with LPS treatment can both 'block' and 'reverse' heterochromatin formation. Forskolin treatment resulted in a similar disassembling effect on heterochromatin. Conversely, inhibition of PKA by H89 or MSK1 both blocked 'normalizing' effects of risperidone on LPS-induced heterochromatin. Our results demonstrate that risperidone can disassemble heterochromatin, exerting this effect along the G-protein/AC/PKA pathway. This approach can also be utilized to investigate functional outcomes of single or combined pharmacological treatments on chromatin assemblies in human cells.


Subject(s)
Antipsychotic Agents/pharmacology , Cyclic AMP-Dependent Protein Kinases/metabolism , Heterochromatin/drug effects , Liposarcoma/drug therapy , Risperidone/pharmacology , Adenylyl Cyclases/metabolism , Animals , Cell Line, Tumor , Chromosomal Proteins, Non-Histone/metabolism , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Cytokines/genetics , Cytokines/metabolism , Epigenesis, Genetic/drug effects , GTP-Binding Proteins/metabolism , Histones/metabolism , Humans , Inflammation Mediators/metabolism , Isoquinolines/pharmacology , Lipopolysaccharides/immunology , Liposarcoma/genetics , Promoter Regions, Genetic/genetics , Signal Transduction , Sulfonamides/pharmacology , Toll-Like Receptor 4/metabolism
12.
Biochem Biophys Res Commun ; 493(3): 1318-1321, 2017 11 25.
Article in English | MEDLINE | ID: mdl-28986254

ABSTRACT

Kinesin-1 is a mechanochemical enzyme which mediates long distance intracellular cargo transport along microtubules in a wide variety of eukaryotic cells. Kinesin is also relatively easy to purify and shows robust function in vitro, leading to numerous proposals for using the kinesin-1/microtubule system for nanoscale transport in engineered devices. However, kinesin in vitro shows signs of degradation at ∼30 °C which severely limits its usability in biomimetic engineering. Notably, kinesin-1 functions robustly in animal cells at body temperatures as high as 40 °C which suggests that kinesin functioning can be stabilized beyond what is observed in vitro. The present study investigated the effect of trimethylamine N-oxide (TMAO) as a potential heat-protecting agent for kinesin function and microtubule stability. We show that at a concentration of 200 mM, TMAO can indeed stabilize kinesin-based motility up to a little over 50 °C and that such motility can be sustained for extended periods of time. Our results suggest that intracellular crowding (mimicked in vitro by TMAO) can indeed stabilize kinesin-1 at high temperatures and helps resolve a long standing discrepancy between thermal stability of kinesin-1 observed in vivo and in vitro. Moreover, when considered together with our previous report that kinesin-1 can function well down to near-freezing conditions, this study establishes kinesin-1/microtubule motility as a thermally viable engineering platform.


Subject(s)
Kinesins/chemistry , Methylamines/chemistry , Animals , Kinesins/metabolism , Microtubules/metabolism , Protein Stability , Temperature
13.
J Schizophr Res ; 2(1)2015.
Article in English | MEDLINE | ID: mdl-27099869

ABSTRACT

OBJECTIVE: The primary aim of this study was to examine first-person phenomenological descriptions of the relationship between the self and Auditory Verbal Hallucinations (AVHs). Complex AVHs are frequently described as entities with clear interpersonal characteristics. Strikingly, investigations of first-person (subjective) descriptions of the phenomenology of the relationship are virtually absent from the literature. METHOD: Twenty participants with psychosis and actively experiencing AVHs were recruited from the University of Illinois at Chicago. A mixed-methods design involving qualitative and quantitative components was utilized. Following a priority-sequence model of complementarity, quantitative analyses were used to test elements of emergent qualitative themes. RESULTS: The qualitative analysis identified three foundational constructs in the relationship between self and voices: 'understanding of origin,' 'distinct interpersonal identities,' and 'locus of control.' Quantitative analyses further supported identified links of these constructs. Subjects experienced their AVHs as having identities distinct from self and actively engaged with their AVHs experienced a greater sense of autonomy and control over AVHs. DISCUSSION: Given the clinical importance of AVHs and emerging strategies targeting the relationship between the hearer and voices, our findings highlight the importance of these relational constructs in improvement and innovation of clinical interventions. Our analyses also underscore the value of detailed voice assessments such as those provided by the Maastricht Interview are needed in the evaluation process. Subjects narratives shows that the relational phenomena between hearer and AVH(s) is dynamic, and can be influenced and changed through the hearers' engagement, conversation, and negotiation with their voices.

14.
Br J Radiol ; 87(1038): 20130746, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24678856

ABSTRACT

OBJECTIVE: Occupational radiation doses from fluoroscopic procedures are some of the highest doses of exposure amongst medical staff using radiography. Protective equipment and dose monitoring are used to minimize and control the risk from these occupational doses. Other studies have considered the effectiveness of this protection, but this study further considers whether protection is adequate for the lower leg and foot and the extent to which these doses can be reduced. METHODS: Scatter air kerma profiles at toe level were measured with an ionization chamber. Thermoluminescent dosemeters and lower extremity phantoms were used to estimate the dose variation with the height of patient couch. A 7-week period of in situ toe dose monitoring of four radiologists was also undertaken. RESULTS: The use of protective curtains effectively reduced the exposure to most of the lower extremities. Toe doses were found to be high and increased with increase in couch height. In situ monitoring indicated annual toe doses of 110 mSv for two of the four radiologists monitored. CONCLUSION: Protective curtains should be used, but they might have limitations with respect to toe doses. Annual toe doses approaching the classification threshold of 150 mSv were measured for two radiologists. Caution should be exercised when there is a gap below curtains and, when possible, staff should step back from the couch. Lower legs and toes should be included in local radiation protection programmes. ADVANCES IN KNOWLEDGE: Toe doses in interventional radiology may be higher than expected and may have to be included in radiation protection programmes.


Subject(s)
Lower Extremity/radiation effects , Occupational Exposure/prevention & control , Radiation Dosage , Radiation Protection/instrumentation , Fluoroscopy , Humans , Phantoms, Imaging , Radiography, Interventional , Thermoluminescent Dosimetry
15.
J Zool (1987) ; 291(1)2013 Sep 01.
Article in English | MEDLINE | ID: mdl-24363497

ABSTRACT

Body size is an important determinant of resource and mate competition in many species. Competition is often mediated by conspicuous vocal displays, which may help to intimidate rivals and attract mates by providing honest cues to signaler size. Fitch proposed that vocal tract resonances (or formants) should provide particularly good, or honest, acoustic cues to signaler size because they are determined by the length of the vocal tract, which in turn, is hypothesized to scale reliably with overall body size. There is some empirical support for this hypothesis, but to date, many of the effects have been either mixed for males compared with females, weaker than expected in one or the other sex, or complicated by sampling issues. In this paper, we undertake a direct test of Fitch's hypothesis in two canid species using large samples that control for age- and sex-related variation. The samples involved radiographic images of 120 Portuguese water dogs Canis lupus familiaris and 121 Russian silver foxes Vulpes vulpes. Direct measurements were made of vocal tract length from X-ray images and compared against independent measures of body size. In adults of both species, and within both sexes, overall vocal tract length was strongly and significantly correlated with body size. Effects were strongest for the oral component of the vocal tract. By contrast, the length of the pharyngeal component was not as consistently related to body size. These outcomes are some of the clearest evidence to date in support of Fitch's hypothesis. At the same time, they highlight the potential for elements of both honest and deceptive body signaling to occur simultaneously via differential acoustic cues provided by the oral versus pharyngeal components of the vocal tract.

16.
Pharmacogenomics J ; 12(5): 361-7, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22249356

ABSTRACT

Heterochromatin is a higher order assembly that is characterized by a genome-wide distribution, gene-repression, durability and potential to spread. In this light, it is an appealing mechanism to interpret the neurobiology of complex brain disorders such as schizophrenia where downregulation of expression appears to be the norm. H3K9 methylation (H3K9me) can initiate the seeding of a heterochromatin assembly on an inactive or poorly coordinated promoter as a consequence of a decline in transactivators either from disuse or from misuse. H3K9me can extend its influence by spatial spreading through the mechanism of recursively recruiting adapters, such as heterochromatin protein 1 (HP1) homodimers. HP1 itself serves as a platform for other repressive proteins such as DNA methyltransferases. In full color, heterochromatin can occupy genome-wide gene networks, tissue specific ontologies and even rearrange the nuclear architecture. Heterochromatin in the brain is modified by small molecule pharmacology and serves a physiological role in the functioning of dopamine neurons and the construction of memory. From a therapeutic perspective, the durable nature of heterochromatin implies that it may require disassembly before the full genomic-potential of standard pharmacotherapies is achieved, especially in treatment resistant patients.


Subject(s)
Chromosomal Proteins, Non-Histone/genetics , Heterochromatin/genetics , Histone-Lysine N-Methyltransferase/genetics , Schizophrenia/metabolism , Acetylation , Chromatin Assembly and Disassembly , Chromobox Protein Homolog 5 , Chromosomal Proteins, Non-Histone/metabolism , Gene Expression Regulation , Histocompatibility Antigens/metabolism , Histone-Lysine N-Methyltransferase/antagonists & inhibitors , Histone-Lysine N-Methyltransferase/metabolism , Histones/genetics , Histones/metabolism , Humans , Schizophrenia/physiopathology
17.
Article in English | MEDLINE | ID: mdl-19717540

ABSTRACT

The domestic dog offers a remarkable opportunity to disentangle the genetics of complex phenotypes. Here, we explore a locus, previously identified in the Portuguese water dog (PWD), associated with PC2, a morphological principal component characterized as leg width versus leg length. The locus was initially mapped to a region of 26 Mb on canine chromosome 12 (CFA12) following a genome-wide scan. Subsequent and extensive genotyping of single-nucleotide polymorphisms (SNPs) and haplotype analysis in both the PWD and selected breeds representing phenotypic extremes of PC2 reduced the region from 26 Mb to 500 kb. The proximity of the critical interval to two collagen genes suggests that the phenotype may be controlled by cis-acting mechanisms.


Subject(s)
Dogs/anatomy & histology , Dogs/genetics , Extremities/anatomy & histology , Animals , Chromosome Mapping , Genetic Association Studies , Genome-Wide Association Study , Haplotypes , Phenotype , Polymorphism, Single Nucleotide , Quantitative Trait Loci
18.
Ultraschall Med ; 30(6): 564-70, 2009 Dec.
Article in German | MEDLINE | ID: mdl-19544229

ABSTRACT

PURPOSE: The aim of this study was the follow-up of children with a prenatal diagnosis of supraventricular extrasystole (SVES) up to an age of 5 years in order to assess the long term outcome of these children and in order to characterize factors influencing the outcome. MATERIALS AND METHOD: All fetuses diagnosed with prenatal SVES between April 1993 and August 2005 were identified and the children's parents and pediatricians contacted for data regarding the children's health. Follow-up data about the children's health up to the age of 5 years could be obtained in 77 (46.1%) children. RESULTS: 0.5% (167/34,770) of all fetuses were diagnosed with prenatal SVES. In 70% of cases the SVES resolved before or at birth. 30% of children presented with arrhythmia postpartum. 31% of children were diagnosed with cardiac anomalies postpartum. 87% of children were healthy at the age of 2 - 5 years. In the subgroup of children with isolated fetal SVES without further anomalies, 95% of children were healthy at the age of 2 - 5 years. In children with persisting arrhythmia and in children with cardiac anomalies, the prognosis was worse. CONCLUSIONS: Overall, by the long-term follow-up of 77 children with prenatal SVES we could show that prenatal SVES has a good prognosis. However, 30% of children develop arrhythmia postpartum and 31% of children present with cardiac anomalies. These children still have a worse prognosis than children with isolated prenatal SVES.


Subject(s)
Ventricular Premature Complexes/diagnostic imaging , Ventricular Premature Complexes/embryology , Abortion, Spontaneous/epidemiology , Child , Cohort Studies , Echocardiography , Female , Follow-Up Studies , Humans , Interviews as Topic , Live Birth , Pregnancy , Pregnancy Outcome/epidemiology , Pregnancy Trimester, Second , Prenatal Diagnosis , Reference Values , Retrospective Studies , Telephone , Ultrasonography, Doppler , Ultrasonography, Prenatal/methods
19.
Behav Genet ; 38(2): 185-94, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18030612

ABSTRACT

Strains of silver foxes, selectively bred at the Institute of Cytology and Genetics of the Russian Academy of Sciences, are a well established, novel model for studying the genetic basis of behavior, and the processes involved in canine domestication. Here we describe a method to measure fox behavior as quantitative phenotypes which distinguish populations and resegregate in experimental pedigrees. We defined 50 binary observations that nonredundantly and accurately distinguished behaviors in reference populations and cross-bred pedigrees. Principal-component analysis dissected out the independent elements underlying these behaviors. PC1 accounted for >44% of the total variance in measured traits. This system clearly distinguished tame foxes from aggressive and wildtype foxes. F1 foxes yield intermediate values that extend into the ranges of both the tame and aggressive foxes, while the scores of the backcross generation resegregate. These measures can thus be used for QTL mapping to explore the genetic basis of tame and aggressive behavior in foxes, which should provide new insights into the mechanisms of mammalian behavior and canine domestication.


Subject(s)
Aggression , Foxes/genetics , Genome , Quantitative Trait Loci , Animals , Animals, Domestic/genetics , Animals, Wild/genetics , Crosses, Genetic , Dogs/genetics , Humans , Models, Genetic , Pedigree , Video Recording
20.
Proc Natl Acad Sci U S A ; 104(43): 17204-9, 2007 Oct 23.
Article in English | MEDLINE | ID: mdl-17940007

ABSTRACT

Huntington's disease (HD) is a neurodegenerative disorder caused by expansion of a CAG repeat in the huntingtin (Htt) gene. HD is autosomal dominant and, in theory, amenable to therapeutic RNA silencing. We introduced cholesterol-conjugated small interfering RNA duplexes (cc-siRNA) targeting human Htt mRNA (siRNA-Htt) into mouse striata that also received adeno-associated virus containing either expanded (100 CAG) or wild-type (18 CAG) Htt cDNA encoding huntingtin (Htt) 1-400. Adeno-associated virus delivery to striatum and overlying cortex of the mutant Htt gene, but not the wild type, produced neuropathology and motor deficits. Treatment with cc-siRNA-Htt in mice with mutant Htt prolonged survival of striatal neurons, reduced neuropil aggregates, diminished inclusion size, and lowered the frequency of clasping and footslips on balance beam. cc-siRNA-Htt was designed to target human wild-type and mutant Htt and decreased levels of both in the striatum. Our findings indicate that a single administration into the adult striatum of an siRNA targeting Htt can silence mutant Htt, attenuate neuronal pathology, and delay the abnormal behavioral phenotype observed in a rapid-onset, viral transgenic mouse model of HD.


Subject(s)
Cerebral Cortex/pathology , Gene Silencing , Genetic Therapy , Mutant Proteins/antagonists & inhibitors , Neostriatum/pathology , Nerve Tissue Proteins/antagonists & inhibitors , Nuclear Proteins/antagonists & inhibitors , RNA, Small Interfering/pharmacology , Animals , Behavior, Animal/drug effects , Cerebral Cortex/drug effects , Cholesterol/metabolism , Dependovirus , Disease Models, Animal , Humans , Huntingtin Protein , Huntington Disease/pathology , Huntington Disease/therapy , Injections , Intranuclear Inclusion Bodies/drug effects , Intranuclear Inclusion Bodies/pathology , Intranuclear Inclusion Bodies/ultrastructure , Mice , Motor Neuron Disease/pathology , Neostriatum/drug effects , Nerve Tissue Proteins/immunology , Neurons/pathology , Neurons/ultrastructure , Neuropil Threads/drug effects , Neuropil Threads/ultrastructure , Nuclear Proteins/immunology
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