Magnetic anisotropy of asbestos fibres

Original article can be found at : http://jap.aip.org/jap/ Copyright American Institute of PhysicsThe anisotropy of magnetic susceptibility of single asbestos fibers is measured. The alignment of both chrysotile and crocidolite fibers in magnetic fields is found to be due to the anisotropy. The average measured anisotropy of volume susceptibility is 0.40×10−6 for chrysotile and 83×10−6 for crocidolite. Fiber shape effects are estimated to contribute, on average, about 10% and 6%, respectively, to the total anisotropy of the two types of fiber. There is no evidence of significant permanent magnetic moments. The magnitude of the observed alignment makes the effect potentially useful in real-time detection of airborne asbestos fibers. The experimental technique developed in the study can be used for measuring the anisotropy of small particles of well-defined shape. High sensitivity of the technique permits the measurement of torques lower than 10−21 Nm on particles down to picogram mass.Peer reviewe

XRCC1 Deficiency Sensitizes Human Lung Epithelial Cells to Genotoxicity by Crocidolite Asbestos and Libby Amphibole

Background: Asbestos induces DNA and chromosomal damage, but the DNA repair pathways protecting human cells against its genotoxicity are largely unknown. Polymorphisms in XRCC1 have been associated with altered susceptibility to asbestos-related diseases. However, it is unclear whether oxidative DNA damage repaired by XRCC1 contributes to asbestos-induced chromosomal damage

Dinamika funkcije pluća kod azbestne bolesti

As a rule, asbestosis is a disease of workers who are occupationally exposed to inhalation of asbestos dust, leaving permanent alterations on the lung parenchyma or pleura. In our ten-year study, we investigated 318 workers with pleural asbestosis from whom we took medical history which included occupational exposure to asbestos, radiological examinations and lung function, which is mandatory for the diagnosis and the follow up of the disease. We analysed functional parameters such as forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) and intermediate forced expiratory flow at 25 % to 75 % (FEF25 %-75 %). In addition, we investigated the predicted values of functional parameters according to smoking and non-smoking habits. We found a significant reduction in vital capacity, particularly in smokers after 25 years of exposure to asbestos. During the first 15 years, values of vital capacity on the group basis remained inside the 80 % of the normal values and were not significant for assessing the dynamics of the lung function. To better assess the effects of occupational asbestos exposure, it is necessary to interpret lung function data not only on the group basis, but also for each subject individually.Azbestoza je bolest izazvana udisanjem azbestnih čestica koje ostavljaju trajne promjene na parenhimu pluća i/ili pleuri. Dijagnoza se postavlja na osnovi anamnestičkih podataka, uvidom u profesionalnu izloženost azbestu i radiološkom obradom te patohistološkom potvrdom promjena na plućima i/ili pleuri. Funkcionalna obrada pluća obavezna je u postavljanju dijagnoze i praćenju bolesti. Tijekom desetogodišnjeg istraživanja funkcionalno smo obradili 318 osoba profesionalno izloženih azbestu s dokazanom azbestozom pleure. Analizirane su vrijednosti funkcionalnih parametara, i to forsiranoga vitalnog kapaciteta (FVC), forsiranoga ekspiracijskog volumena u prvoj sekundi (FEV1) i srednjega ekspiracijskog protoka (FEF25 %-75 %). Dokazan je statistički signifikantan pad vrijednosti FVC i FEV1. Dodatno smo istražili vrijednosti funkcionalnih parametara kod naših ispitanika s navikom pušenja i nepušača. U obje skupine prisutno je značajno sniženje vrijednosti vitalnog kapaciteta tijekom istraživanja, s tim da nakon 25 godina izloženosti azbestu kod pušača dolazi do naglog pada vrijednosti vitalnog kapaciteta u odnosu na nepušače. Bitno je uočiti da tijekom prvih 15 godina vrijednosti vitalnog kapaciteta ostaju unutar 80 % normalnih vrijednosti te nemaju značenja za praćenje dinamike funkcije pluća kod azbestne bolesti. Individualnim praćenjem profesionalno izloženih radnika ostvaruje se bolji uvid u dinamiku funkcije pluća kod azbestne bolesti

Human Health Risk Assessment For Arsenic: A Critical Review

Millions of people are exposed to arsenic resulting in a range of health implications.This paper provides an up-to-date review of the different sources of arsenic (water, soil and food), indicators of human exposure (biomarker assessment of hair, nail, urine and blood), epidemiological and toxicological studies on carcinogenic and non-carcinogenic health outcomes, and risk assessment approaches. The review demonstrates a need for more work evaluating the risks of different arsenic species such as; arsenate, arsenite monomethylarsonic acid, monomethylarsonous acid, dimethylarsinic acid and dimethylarsinous acid as well as a need to better integrate the different exposure sources in risk assessments

Outcomes 1 year after non-operative management of uncomplicated appendicitis in children: Children with AppendicitiS during the CoronAvirus panDEmic (CASCADE) study

BACKGROUND: A major shift in treatment of appendicitis occurred early in the SARS-CoV-2 pandemic with non-operative management used commonly outside research protocols and in units with limited previous experience. This study aims to compare real-world outcomes of surgery versus non-operative management of uncomplicated appendicitis in children with 1-year follow-up. METHOD: A prospective multicentre observational study of children treated for uncomplicated appendicitis at 74 hospitals in the UK and Ireland from 1 April to 31 July 2020 was performed. Propensity-score matched analysis was conducted using age, sex, C-reactive protein at diagnosis and duration of symptoms as covariates. Primary outcomes were success of non-operative management defined as achieving 1-year follow-up without undergoing appendicectomy due to recurrent appendicitis or ongoing symptoms, and occurrence of any predefined complication (intra-abdominal collection, wound infection, bowel obstruction or reintervention). RESULTS: Of 1464 children with presumed uncomplicated appendicitis, 1027 (70.2 per cent) underwent surgery and 437 (29.9 per cent) underwent non-operative management. Ninety-four children (21.5 per cent) treated by initial non-operative management required appendicectomy during the index hospital admission while recurrent appendicitis after discharge occurred in 25 (10.4 per cent) children within 1 year. The overall success rate of non-operative management at 1 year was 63.1 per cent (95 per cent c.i. 58.0 to 68.3 per cent). For propensity-score matched analyses, 688 children undergoing surgery and 307 undergoing non-operative management were included. Any predefined complication occurred in 50 (7.3 per cent) children undergoing surgery and in four (1.3 per cent) children undergoing non-operative management (OR 5.9 (95 per cent c.i. 2.1 to 16.6)) in the propensity-score matched cohort. There was no mortality or stoma formation. CONCLUSION: Non-operative management is a safe and valid alternative to appendicectomy in children with uncomplicated appendicitis

Altered Metabolism of Growth Hormone Receptor Mutant Mice: A Combined NMR Metabonomics and Microarray Study

Growth hormone is an important regulator of post-natal growth and metabolism. We have investigated the metabolic consequences of altered growth hormone signaling in mutant mice that have truncations at position 569 and 391 of the intracellular domain of the growth hormone receptor, and thus exhibit either low (around 30% maximum) or no growth hormone-dependent STATS signaling respectively. These mutants result in altered liver metabolism, obesity and insulin resistance