Occupational orthopedic problems and its relation to personal radiation protection in interventional radiology.

PURPOSE: Several studies report occupational orthopedic problems among interventional cardiologists. These health problems are usually multifactorial. However, the personal protective equipment used should play a major role. An online survey was conducted to determine the frequency of such health problems among interventional radiologists and to correlate them with the use of personal radiation protective clothing. MATERIAL AND METHODS: An anonymous online survey that comprised of 17 questions was sent via e-mail to 1427 members of the German Society for Interventional Radiology (DeGIR) in Germany, Austria and Switzerland. The questions were focused on interventional workload, the use of personal radiation protection apparel and orthopedic problems. Given the different scale levels, the associations between the variables were analyzed using different statistical methods. A significance level of p < 0.05 was chosen. RESULTS: There were 221 survey responders (15.5% response rate). About half of responders (47.7%) suffered from more than five episodes of orthopedic problems during their interventional career. Lumbar spine was involved in 81.7% of these cases, cervical spine in 32.8%, shoulder in 28.5% and knee in 24.7%. Because of orthopedic problems, 16.1% of the responders had to reduce and 2.7% had to stop their interventional practice. The number of affected body regions correlates with the fit of the radiation protection means (p < 0.05, r = 0.135) and the reduction of activity as an interventional radiologist (p < 0.05, r = -0.148). CONCLUSION: Overall, the survey reveals widespread orthopedic problems at several body regions among interventional radiologists, associated with the fit of radiation protection systems, among other factors. A connection between the orthopaedic complaints and the radiation protection system used could not be established.

The role of the retinal vasculature in age-related macular degeneration: a spotlight on OCTA.

Age-related macular degeneration (AMD) remains a disease with high morbidity and an incompletely understood pathophysiological mechanism. The ocular blood supply has been implicated in the development of the disease process, of which most research has focused on the role of the choroid and choriocapillaris. Recently, interest has developed into the role of the retinal vasculature in AMD, particularly with the advent of optical coherence tomography angiography (OCTA), which enables non-invasive imaging of the eye's blood vessels. This review summarises the up-to-date body of work in this field including the proposed links between observed changes in the retinal vessels and the development of AMD and potential future directions for research in this area. The review highlights that the strongest evidence supports the observation that patients with early to intermediate AMD have reduced vessel density in the superficial vascular complex of the retina, but also emphasises the need for caution when interpreting such studies due to their variable methodologies and nomenclature.

Mortality, incidence and seasonality of canine and feline patients treated with tick antiserum in three far North Queensland veterinary clinics from 2000 to 2020.

Tick paralysis is a paralysis caused by bites from Ixodes holocyclus, affecting an estimated 10,000 companion animals in Australia annually. Despite tick antiserum being the cornerstone of treatment, there are no large-scale general practice studies that examine survival outcomes in tick antiserum-treated animals. In this retrospective study, clinical records from three far north Queensland general practice veterinary clinics were searched for tick antiserum-treated canine and feline patients were seen between 2000 and 2020. Patient records were assessed for survival outcomes, then logistic regression and Bayesian structural time-series model were used to assess trends in incidence and mortality and the relationship between these and time of year, rainfall, and species. The study included 2019 dog and 953 cat records. When patients with unknown outcomes were removed, canine mortality was 11.8% (213/1799) and feline mortality was 5.3% (46/872). Dogs were found to have 2.41 odds of dying following treatment than cats. August and September had the highest mean number of monthly treatments, and rainfall in the previous 5-8 months was positively correlated with the number of patients treated in each month. The odds of mortality did not vary significantly by month or season, and from 2015 onwards, there was a significant decrease in the proportion of dogs treated by the clinics. Overall, this study provides new information on tick antiserum treatment outcomes in general practice as well as new information on tick paralysis incidence in far north Queensland.

Joint replacement increases radiation exposure to the staff in angiography: A phantom study.

INTRODUCTION: The present study investigates the influence of joint prostheses on the amount of scattered radiation in a simulated angiography set-up. MATERIALS AND METHODS: A clinical angiography system (Artis Zee, Siemens Healthineers, Germany) with a water phantom as a scattering object was used. The scattered radiation of the water phantom was repeatedly measured without prosthesis, with a knee prosthesis and a hip prosthesis made from titanium, aluminum, vanadium, ceramics and polyethylene. For radiation measurement an ionization chamber (ambient dose equivalent rate from 0.1 µSv/h - 100 Sv/h, UMo, Berthold Technologies, Germany) was used. It was positioned on the right side of the phantom simulating an interventional procedure via the right femoral artery. The ionization chamber was positioned at 5 different heights (30, 100, 130, 150 and 165 cm), simulating different body parts of the interventionist. In addition, the amount of scattered radiation in relation to the tube angulation was investigated. RESULTS: Averaged over all angulations at a height of 165 cm, the radiation dose was 2.7 times higher (1935 µSv/h, p < 0.01) when a hip prosthesis was present in comparison to no prosthesis (713 µSv/h). The radiation dose was 3.9 times higher with the integration of a knee prosthesis (2778 µSv/h, p < 0.01) compared to that without prosthesis. The average radiation dose over all angulations and all heights was 1491 µSv/h without prosthesis, 4538 µSv/h with a hip prothesis and 5023 µSv/h with a knee prosthesis respectively. CONCLUSION: This experimental study shows a significant increase in the radiation dose when a joint prosthesis is present in the examination field. Special attention and sufficient radiation protection is therefore necessary for investigations with implanted prostheses.

Single-cell eQTL mapping identifies cell type-specific genetic control of autoimmune disease.

The human immune system displays substantial variation between individuals, leading to differences in susceptibility to autoimmune disease. We present single-cell RNA sequencing (scRNA-seq) data from 1,267,758 peripheral blood mononuclear cells from 982 healthy human subjects. For 14 cell types, we identified 26,597 independent cis-expression quantitative trait loci (eQTLs) and 990 trans-eQTLs, with most showing cell type-specific effects on gene expression. We subsequently show how eQTLs have dynamic allelic effects in B cells that are transitioning from naïve to memory states and demonstrate how commonly segregating alleles lead to interindividual variation in immune function. Finally, using a Mendelian randomization approach, we identify the causal route by which 305 risk loci contribute to autoimmune disease at the cellular level. This work brings together genetic epidemiology with scRNA-seq to uncover drivers of interindividual variation in the immune system.

Demyelinating Events Following Initiation of Anti-TNFα Therapy in the British Society for Rheumatology Biologics Registry in Rheumatoid Arthritis.

OBJECTIVE: To establish the incidence of demyelination in patients who have received anti-tumor necrosis factor alpha (anti-TNFα) therapy, through analysis of adverse events reported in a prospective cohort of patients receiving biological therapies. METHODS: A cohort study was performed on prospectively acquired data via the British Society for Rheumatology Biologics Register in Rheumatoid Arthritis. All potential demyelinating events during follow-up were extracted and classified as definite, probable, or possible blinded to treatment data. The point of starting an anti-TNF therapy in individuals with no prior reported demyelination was the time of exposure. Crude rates of demyelination and standardized incident rates (SIRs) compared with the general UK population were calculated. RESULTS: Thirty-five individuals with demyelinating events were identified from a total pool of 13,489. The median age at study entry was 44 years, and the median disease duration was 8 years; 71% were female. Events occurred a median of 3 (interquartile range 1-5) years from the start of the first anti-TNF therapy. Twenty-six events occurred in individuals still taking anti-TNFα therapy; of the other 9, 6 were within 90 days of drug withdrawal. The raw incidence of demyelination was 19.7/100,000 patient-years (95% CI 13.7-27.3). The SIR in the whole population was 1.38 (95% CI 0.96-1.92) and 0.83 (0.51-1.26) limited to definite/probable cases. CONCLUSIONS: Demyelination following anti-TNF therapy is uncommon. Patients receiving anti-TNFα therapy show a marginally increased SIR; this is lost in sensitivity analyses. Patients concerned about anti-TNFα-associated demyelination can be relatively reassured by these data.

Digital Variance Angiography in Lower-Limb Angiography with Metal Implants.

PURPOSE: The presence of metal implants may reduce angiographic image quality due to automated beam adjustments. Digital variance angiography (DVA) is reported to be superior to digital subtraction angiography (DSA) with increased contrast-to-noise ratio (CNR) and better image quality. The aim of the study was to evaluate whether DVA could counterbalance the image quality impairment of lower-limb angiographies with metal implants. MATERIALS AND METHODS: From November 2019 to January 2020, 85 raw lower-limb iodine contrast angiograms of 12 patients with metal implants were processed retrospectively with DVA analyses. For objective comparison, CNR of DSA and DVA images was calculated and the ratio CNRDVA/CNRDSA was determined. Visual image quality was evaluated in a paired comparison and by a five-grade Likert scale by three experienced radiologists. RESULTS: The CNR was calculated and compared in 1252 regions of interest in 37 image pairs containing metal implants. The median ratio of CNRDVA/CNRDSA was 1.84 with an interquartile range of 1.35-2.32. Paired comparison resulted in 84.5% in favour of DVA with an interrater agreement of 83.2% (Fleiss κ 0.454, p < 0.001). The overall image quality scores for DSA and DVA were 3.64 ± 0.08 and 4.43 ± 0.06, respectively (p < 0.001, Wilcoxon signed-rank test) with consistently higher individual ratings for DVA. CONCLUSION: Our small-sample pilot study shows that DVA provides significantly improved image quality in lower-limb angiography with metal implants, compared to DSA imaging. The improved CNR suggest that this approach could reduce radiation exposure for lower-limb angiography with metal implants. LEVEL OF EVIDENCE: Level 4, case studies.

Scatter radiation reduction with a radiation-absorbing pad in interventional radiology examinations.

PURPOSE: Radiation-absorbing pads are an additional possibility to reduce scattered radiation at its source. The goal of this study is to investigate the efficacy of a new reusable radiation-absorbing pad at its origin in an experimental setup. MATERIAL AND METHODS: All measurements were carried out using a clinical angiography system with a standardized fluoroscopy protocol, different C-arm angulations and an anthropomorphic torso phantom as a scattering body. An ionization chamber was used to measure the radiation exposure at five different heights of a simulated operator during a simulated transfemoral angiography intervention. Measurements were carried out with and without radiation-absorbing pads with lead equivalents of 0.25 and 0.5 mm placed onto the scattering body. For all measurements a mobile acrylic shield and an under-table lead curtain was used. RESULTS: At all operator heights from 100 to 165 cm a significant radiation dose reduction of up to 80.6 % (p < 0.01) using the radiation-absorbing pad was measured, when compared to no radiation-absorbing pad. At the height of 165 cm the radiation-absorbing pad with a lead equivalence of 0.5 mm showed a significant radiation dose reduction (51.4 %, p < 0.01) in comparison to a lead equivalence of 0.25 mm. CONCLUSION: The addition of a radiation-absorbing pad to the standard protection means results in a significant dose reduction for the operator, particularly for upper body parts.

Comparison of different resuscitation methods with regard to injury patterns in cardiac arrest survivors based on computer tomography.

PURPOSE: To ensure that patients survive cardiac arrest, cardiopulmonary resuscitation (CPR) is needed. However, the procedure itself can lead to severe injuries. This study aims to examine both possibilities of resuscitation - mechanical or manual - with regard to their risk of injury. To this end, we compare the injuries patterns in both groups of patients after successful resuscitation based on computer tomography (CT). METHODS: This single-centre retrospective study included 32 patients (female: 21.87 %, male: 78.12 %, Mean age: 60.22 ± 13.93 years) with cardiac arrest followed by successful mechanical CPR, who underwent an early whole-body CT. A control group of 32 patients (female: 21.87 %, male: 78.12 %, mean age: 60.75 ± 13.34 years) that had been resuscitated successfully with manual CPR was matched according to gender and age for a better statistical comparison. Patients with cardiac arrest due to trauma were excluded from the study population. RESULTS: Mechanically resuscitated patients showed significantly more CPR-related injuries than those who were resuscitated manually (100 % vs. 84.37 %; p = 0.02). In particular, dislocated rib fractures (40.47 vs. 23.80 mean rank, p < 0.01), sternal fractures (74.19 % vs. 25 %; p < 0,01), bleeding complications (29.03 % vs. 3.12 %; p = 0.01), pneumothorax (38.71 % vs. 9.37 %; p = 0.01), mediastinal haematomas (58.01 % vs. 25 %, p = 0.01) and liver lacerations (29.03 % vs. 0 %, p = 0.04) were observed significantly more in patients after mechanical CPR compared to those with manual resuscitation. CONCLUSIONS: The guideline-based use of mechanical CPR results in a significant increase of internal and musculoskeletal injuries compared to manual CPR.

Early whole-body CT for treatment guidance in patients with return of spontaneous circulation after cardiac arrest.

PURPOSE: Non-traumatic cardiac arrest (CA) and return of spontaneous circulation (ROSC) after cardiopulmonary resuscitation (CPR) are often associated with multiple pathologies. Expecting a high prevalence of important findings, a whole-body CT (WBCT) could be of relevance for therapy. The aim of this study is to investigate the feasibility and diagnostic yield of an early WBCT in this setting. METHODS: This single-center retrospective study included 100 consecutive patients (27 female; 73 male; mean age 68.5± 12.57 years) with non-traumatic, in- and out-of-hospital CA and ROSC following CPR, who underwent a contrast-enhanced WBCT within 6 h after ROSC over 12 months. CT findings were determined corresponding to anatomical region. RESULTS: Early WBCT was successfully carried out in 100% of the patients with CA and ROSC after CPR. Acute pathologies were found not only in the chest but also in the head (15%) and the abdomen (6%). Early global brain edema (n = 12), acute stroke (n = 3), pulmonary embolism (n = 10), pneumothorax (26%), acute abdominal pathologies (n = 6), iatrogenic bleeding (4%), and CPR-related injuries (93%) were detected by CT right from the beginning of the post-cardiac arrest care. CONCLUSIONS: An early WBCT is feasible and provides added diagnostic value for patients with ROSC after non-traumatic CA.

Protective Efficacy of Different Ocular Radiation Protection Devices: A Phantom Study.

PURPOSE: The aim of this study was to investigate the efficacy of different designs and types of ocular radiation protection devices depending on simulated varied body heights in a phantom-simulated thoracic intervention. MATERIALS AND METHODS: A clinical angiography system with a standardized fluoroscopy protocol with an anthropomorphic chest phantom as a scattering object and optically stimulated luminescence dosimeters for measuring radiation dose were used. The dosimeters were placed at the position of eyes of an anthropomorphic head phantom simulating the examiner. The head phantom was placed on a height-adjustable stand simulating the height of the examiner from 160 to 200 cm with 10 cm increments. The dose values were then measured with no radiation protection, a weightless-like radiation protection garment, radiation protection glasses and visors. RESULTS: The average dose reduction using radiation protection devices varied between 57.7 and 83.4% (p < 0.05) in comparison with no radiation protection. Some radiation protection glasses and visors showed a significant dose reduction for the eye lenses when the height of the examiner increased. The right eye was partially less protected, especially if the distances between the simulated examiner's head and the scatter object were small. CONCLUSION: All the investigated protection devices showed a significant reduction in radiation exposure to the simulated examiner. For some devices, the radiation dose increased with decreasing distance to the scattering object, especially for the right eye lens.

The implications of integrated assessment and modelling studies for the future remediation of chromite ore processing residue disposal sites.

Chromite ore processing residue (COPR) waste from a former chromium chemical works (1830-1968) is still contaminating groundwater in Glasgow, Scotland, with carcinogenic hexavalent chromium, Cr(VI). An integrated analytical, experimental and modelling approach has identified and accounted for mineral phases and processes responsible for the retention and release of Cr(VI) under prevailing field conditions. Both the nature of mineral phase retention and the buffered high pH of the sites, however, militate against direct remediative treatment of the source material, for example by the application of generic methods (e.g. FeSO4) that have been successfully employed elsewhere for the reduction of Cr(VI) to Cr(III) in other matrices. The interception and treatment of groundwater to remove Cr(VI) and the capping of sites to reduce human exposure to airborne Cr(VI)-contaminated dust may well be more realistic and effective, at least in the short to medium term.

Sexual activity and condom use among Eastern European adolescents--the Study of Hungarian Adolescent Risk Behaviours.

While rates of HIV and STD infection in Eastern Europe are increasing rapidly, little is known about sexual behaviour, including condom use, among Eastern European youths. The Study of Hungarian Adolescent Risk Behaviours was designed to assess the knowledge, attitudes, and behaviours of adolescents studying in secondary schools in Budapest, Hungary. Students (n =3486) in a random sample of public secondary schools completed a self-administered questionnaire, including measures of sexual activity and condom use. Thirty-eight percent of students reported ever having had vaginal intercourse. Condom use by those reporting having had sex in the past five weeks was classified as consistent/every time (40%); irregular (25.6%); and none (34.3%). Multivariate analysis revealed positive opinions about condoms, fear of AIDS, and initiation of condom use by both partners to predict more frequent condom use. Implications for targeted AIDS/STD education and prevention among adolescents are discussed.

Effect of gut transposition on the expression of the endocrine gene neurotensin.

Expression of the gene encoding neurotensin (NT/N) is developmentally regulated in the adult small bowel with maximal expression noted in the distal ileum; the mechanisms responsible for this strict spatial-specific expression pattern are not known. The purpose of this study was to determine whether NT/N expression is altered by ileojejunal transposition. Rats underwent either sham operation or ileojejunal transposition and were killed 2 months after operation. The transposed (either jejunum or ileum) and sham-operated segments of gut were removed, a portion was processed for histologic examination, and the remainder was extracted for total RNA and analyzed by ribonuclease protection using a rat NT/N probe. For comparison, expression of another gut endocrine gene, peptide YY, and an enterocyte-specific gene, sucrase-isomaltase (SI), was also determined. Expression of the gut endocrine genes, NT/N and peptide YY, were minimally affected by transposition of either the jejunum or ileum. In contrast, SI expression was markedly altered in both the transposed jejunum and ileum compared with corresponding sham gut segments. Expression of the NT/N gene is minimally altered after jejunoileal transposition despite marked adaptive and morphologic changes in the transposed segments. These findings provide further support that the strict pattern of NT/N expression is "imprinted" in the gut and maintained regardless of location along the cephalocaudal gut axis.

Constitutional, biochemical and lifestyle correlates of fibrinogen and factor VII activity in Polish urban and rural populations.

BACKGROUND: Fibrinogen and factor VII activity are known to be related to atherosclerosis and coronary heart disease, but population differences in clotting factors and modifiable characteristics that influence their levels have not been widely explored. METHODS: This paper examines correlates of plasma fibrinogen concentration and factor VII activity in 2443 men and women aged 35-64 in random samples selected from the residents in two districts in urban Warsaw (618 men and 651 women) and from rural Tarnobrzeg Province (556 men and 618 women) screened in 1987-1988, and assesses which characteristics might explain urban-rural differences. Fibrinogen and factor VII activity were determined using coagulation methods. RESULTS: Fibrinogen was 12.9 mg/dl higher in men and 14.1 mg/dl higher in women in Tarnobrzeg compared to Warsaw. Factor VII activity was higher in Warsaw (9.2% in men and 15.3% in women). After adjustment for selected characteristics, fibrinogen was higher in smokers compared to non-smokers by 28 mg/dl in men and 22 mg/dl in women. In women, a 15 mg/dl increase in HDL-cholesterol was associated with a 10 mg/dl decrease in fibrinogen (P < 0.01). After adjustment for other variables, a higher factor VII activity in Warsaw remained significant (a difference of 9.4% in men and 14.8% in women). Lower fibrinogen in Warsaw remained significant only in women (15.4 mg/dl difference). CONCLUSIONS: The study confirmed that sex, age, BMI, smoking and blood lipids are related to clotting factors. However, with the exception of gender differences and smoking, associations between clotting factors and other variables were small and of questionable practical importance.

Blood pressure and heart rate response during exercise in men and women in the USA and Russia lipid research clinics prevalence study.

Examination of blood pressure (BP) and heart rate (HR) measurements at rest and during exercise in samples of USA and Russian middle-aged men and women show significant differences between countries for both genders. Russian men had higher resting systolic blood pressure (SBP) than USA men but lower SBP at both stages of exercise. Russian women had significantly higher resting SBP than USA women at rest and also during exercise. Russian men and women had significantly lower HR at rest and during exercise than USA men and women. Differences between countries were also noted for mean body weight, height, lipid levels, percentages of smokers and several other variables, and it was postulated that differences in these factors might be responsible in part for differences in SBP and HR during exercise. After adjustment for these variables, differences in SBP during exercise between USA and Russian men remained, but differences between USA and Russian women disappeared. For both genders, differences in HR during exercise remained after adjustment. Mortality analyses in USA and Russian men indicated that stage 2 SBP response during exercise was generally not a significant mortality risk factor after adjustment for age, BMI, TC, smoking and resting SBP. In a similar model, stage 2 HR response during exercise was also a non-significant risk factor in mortality.

Root canal morphology of maxillary permanent first molar teeth at various ages.

The root canal anatomy and pulp chamber morphology of 216 maxillary permanent first molar teeth of known age was examined using a radiographic technique after infusion of the root canal system with a radiopaque sodium iothalomate gel. This technique proved to be a rapid and effective method for the examination of root canal morphology and is recommended when root canal anatomy needs to be examined before further investigations are carried out. Over 95% of palatal and disto-buccal roots contained a single root canal. The mesio-buccal root was more complex. All types of configurations were seen. Only 26% of mesio-buccal roots showed a single canal. The pulp canal in all roots appeared to narrow at an early age. In the mesio-buccal root, a definite two-directional calcification pattern was apparent in most teeth by the age of 10. The rate of progress of root formation was very variable. There was no apparent relationship between the type of canal system in the mesio-buccal root and the type of canal orifice present. The transverse cross-sectional shape of the pulp chamber was trapezoidal in 81% of teeth.

Poland-US collaborative study on cardiovascular epidemiology: classification agreement between US National Cholesterol Education Program and European Atherosclerosis Society hyperlipidemia guidelines in selected Polish and US populations.

Data from two epidemiological studies are used to measure the degree to which two well-known guidelines agree in measuring hyperlipidemia in population samples in the US and Poland. The epidemiological studies are the US Lipid Research Clinics Program Prevalence Study and the Pol-MONICA project in Poland and the guidelines are those adopted by the US National Cholesterol Program (USNCEP) and by the European Atherosclerosis Society (EAS). EAS guidelines were analyzed in two ways: Method 1 used triglycerides and total cholesterol only in classifying persons as hyperlipidemics or non-hyperlipidemics; Method 2 used triglycerides, total cholesterol and nine additional risk factors in the classification process. USNCEP guidelines used total cholesterol, low density lipoprotein cholesterol and the same additional nine risk factors used in EAS Method 2 in classifying hyperlipidemics. Classification differences between the two sets of guidelines were high when EAS Method 1 guidelines were compared with USNCEP guidelines. However, EAS Method 2 which included risk factors, compared favorably with USNCEP guidelines in all three populations under study.

Vanillin, a potential agent for the treatment of sickle cell anemia.

Vanillin, a food additive, has been evaluated as a potential agent to treat sickle cell anemia. Earlier studies indicated that vanillin had moderate antisickling activity when compared with other aldehydes. We have determined by high performance liquid chromatography that vanillin reacts covalently with sickle hemoglobin (HbS) both in solution and in intact red blood cells. Hemoscan oxygen equilibrium curves show a dose-dependent left shift, particularly at low oxygen tensions. Rheologic evaluation (pO2 scan Ektacytometry) of vanillin-reacted HbS erythrocytes shows a dose-dependent inhibition of deoxygenation-induced cell sickling. Ektacytometry also suggests that vanillin may have a direct inhibitory effect on HbS polymer formation. Vanillin has no adverse effects on cell ion or water content. X-ray crystallographic studies with deoxyhemoglobin (HbA)-vanillin demonstrate that vanillin binds near His 103 alpha, Cys 104 alpha, and Gln 131 beta in the central water cavity. A secondary binding site is located between His 116 beta and His 117 beta. His 116 beta has been implicated as a polymer contact residue. Oxygen equilibrium, ektacytometry, and x-ray studies indicate that vanillin may be acting to decrease HbS polymerization by a dual mechanism of action; allosteric modulation to a high-affinity HbS molecule and by stereospecific inhibition of T state HbS polymerization. Because vanillin is a food additive on the GRAS (generally regarded as safe) list, and because it has little or no adverse effects at high dosages in animals, vanillin is a candidate for further evaluation as an agent for the treatment of sickle cell disease.