385 research outputs found
Deletion of p66Shc in mice increases the frequency of size-change mutations in the lacZ transgene
No full textUpon oxidative challenge the genome accumulates adducts and breaks that activate the DNA damage response to repair, arrest or eliminate the damaged cell. Thus, reactive oxygen species (ROS) generated by endogenous oxygen metabolism are thought to affect mutation frequency. However, few studies determined the mutation frequency when oxidative stress is reduced. To test whether in vivo spontaneous mutation frequency is altered in mice with reduced oxidative stress and cell death rate, we crossed p66Shc knock out (p66KO) mice, characterized by reduced intracellular concentration of ROS and by impaired apoptosis, with a transgenic line harboring multiple copies of the lacZ mutation reporter gene as part of a plasmid that can be recovered from organs into E. coli to measure mutation rate. Liver and small intestine from 2- and 24- month old, lacZ (p66Shc+/+) and lacZp66KO mice, were investigated revealing no difference in overall mutation frequency but a significant increase of the frequency of size-change mutations in the intestine of lacZp66KO mice. This difference was further increased upon irradiation of mice with X-Ray. Additionally, we found that knocking down cyclophilin D, a gene that facilitates mitochondrial apoptosis acting downstream of p66Shc, increased the size-change mutation frequency in small intestine. Size-change mutations also accumulated in death-resistant embryonic fibroblasts from lacZp66KO mice treated with H(2) O(2.) These results indicate that p66Shc plays a role in the accumulation of DNA rearrangements and suggest that p66Shc functions to clear damaged cells rather than affect DNA metabolism. © 2012 The Authors Aging Cell © 2012 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland
Legal English and the 'modal revolution'
No full textIn this paper the author discusses the present status of shall in legal English. Although it has been by far the most common modal in legal English for at least 600 years, its use is currently in decline, especially in Australia, South Africa and New Zealand. The author identifies the structures that take up the place left by shall in shall-free texts, such as the present simple, may and be to. He focuses in particular on the South Africa Constitution where the definitive version currently in force is completely devoid of shall, unlike the Interim version which was drafted only two or three years earlier. The data relating to such shall-free texts as the South Africa Constitution are compared to ‘World data’ relating to the situation in English-speaking countries in general. He also speculates as to what will happen with shall in legal language in the US and the UK
The habitability and detection of Earth-like planets orbiting cool white dwarfs
No full textSince there are several ways planets can survive the giant phase of the host star, we examine the habitability and detection of planets orbiting white dwarfs. As a white dwarf cools from 6000K to 4000K a planet orbiting at 0.01AU would remain in the Continuous Habitable Zone (CHZ) for ~8Gyr. We show that photosynthetic processes can be sustained on such planets. The DNA-weighted UV radiation dose for an Earth-like planet in the CHZ is less than the maxima encountered on Earth, hence non-magnetic white dwarfs are compatible with the persistence of complex life. Polarisation due to a terrestrial planet in the CHZ of a cool white dwarf is 102 (104) times larger than it would be in the habitable zone of a typical M-dwarf (Sun-like star). Polarimetry is thus a viable way to detect close-in rocky planets around white dwarfs. Multi-band polarimetry would also allow reveal the presence of a planet atmosphere, providing a first characterisation. Planets in the CHZ of a 0.6 M⊙ white dwarf will be distorted by Roche geometry, and a Kepler-11d analogue would overfill its Roche lobe. With current facilities a Super-Earth-sized atmosphereless planet is detectable with polarimetry around the brightest known cool white dwarf. Planned future facilities render smaller planets detectable, in particular by increasing the instrumental sensitivity in the blue
NF-kappaB inhibits T-cell activation-induced, p73-dependent cell death by induction of MDM2
No full textNF-κB is a key transcription factor involved in the regulation of T-cell activation and proliferation upon engagement of the T-cell receptor (TCR). T cells that lack the IκB kinase (IKKβ) are unable to activate NF-κB, and rapidly undergo apoptosis upon activation. NF-κB activation following T-cell receptor engagement induces the expression of Mdm2 through interaction with NF-κB sites in its P1 promoter, and enforced expression of Mdm2 protected T cells deficient for NF-κB activation from activation-induced cell death. In T cells with intact NF-κB signaling, ablation or pharmacologic inhibition of Mdm2 resulted in activation-induced apoptosis. Mdm2 coprecipitates with p73 in activated T cells, and apoptosis induced by inhibition of Mdm2 was p73-dependent. Further, Bim was identified as a p73 target gene required for cell death induced by Mdm2 inhibition, and a p73-responsive element in intron 1 of Bim was characterized. Our results demonstrate a pathway for survival of activated T cells through NF-κB-induced Mdm2, which blocks Bim-dependent apoptosis through binding and inhibition of p73
Evaluating burnout in an institutional setting
No full textIn a research project, 183 medical and paramedical staff, each with at least 5 years of service in a large psychiatric hospital in Malta, were interviewed to find out any burnout effects. It was found that the longer the years of service, the more staff felt they were taking their work problems home. Nevertheless irrespective of length of employment, 78% considered their objectives at work fulfilled. Only 22% gave importance to improved salaries, while 77% opted for more staff meetings and in-service training.peer-reviewe
Treating a case of Savant syndrome
No full textMemory and artistic prodigies among the population at large are uncommon; among the mentally retarded, they are rarer still. This article describes the treatment of such a case, technically known as the Savant Syndrome, seen by occupational therapists at Mount Carmel Psychiatric Hospital and treated over a period of 18 years.peer-reviewe
DAR KARTĄ APIE TRISTIA EX MELITOGAUDO: ARGUMENTAI DISKUSIJAI
No full textŠiame straipsnyje nagrinėjami poleminiai klausimai, kuriuos vis dar kelia pirmasis poemos, pavadintos Tristia ex Melitogaudo: Lament in Greek Verse of a XIIth-century Exile on Gozo, leidimas (Busuttil, Joseph, Stanley Fiorini & Horatio Caesar Roger Vella, eds. 2010. Tristia ex Melitogaudo: lament in Greek verse of a XIIth-century exile on Gozo. Malta: Best Print). Remdamiesi istorine bei filologine teksto analize leidėjai pagrindžia savo poziciją kai kuriais kritiniais klausimais ir atsako į M. D. Lauxtermanno straipsnyje (Lauxtermann, Marc D. 2014. Tomi, Mljet, Malta. Critical Notes on a Twelfth-Century Southern Italian Poem of Exile. Jahrbuch der Ősterreichischen Byzantinistik 64, 155–176) pateikiamus kritinius argumentus
Brain damage following whooping cough vaccination : is it time to lay the myth to rest?
No full textWhooping cough causes significant morbidity and mortality, especially in early infancy. Although an effective vaccine exists, vaccine uptake in Malta was previously disappointing due to the general public’s and the medical community’s doubts regarding vaccine efficacy and safety. The aim of this study was to review population-based studies which have analysed the potential short and long term neurological sequelae following pertussis and pertussis vaccination, to describe vaccine uptake globally and in Malta over the past 15 years, and to analyse the effect of vaccine uptake on pertussis epidemics in Malta. This study found that pertussis vaccine uptake has only become satisfactory in recent years, with a resulting attenuation in the most recent pertussis outbreak. Uptake has increased progressively all over the world, and no study has ever incriminated pertussis vaccination as a cause of permanent neurological disability, both locally and abroad. This should encourage the present continuing trend of pertussis uptake.peer-reviewe
The incidence of colorectal tumours in the Maltese islands
No full textColorectal neoplasm is one of the commoner forms of malignant disease; according to the Annual Report Registrar General, 1970 its incidence in England and Wales is second only to that of lung cancer. A survey of the hundred and seventy three patients documented in the Malta Tumour Registry as suffering from colorectal neoplasms between the years 1969-1972 (inclusive) was carried out. Several findings emanate from this survey such as the incidence in the younger age group, the presence of significant nausea and vomiting in fifty percent of the patients of the left hemicolon and twenty percent of cases with a tumour in the right hemicolon. Moreover, this survey has shown that there is an average delay of about six months from the time the patient first presents to his own practitioner until his hospitalization for investigation with yet further delays before surgery is attempted.peer-reviewe
An International Pilot Study of K-12 Teachers’Computer Science Self-Esteem
No full textComputer Science (CS) is a new subject area for many K-12 teachersaround the world, requiring new disciplinary knowledge and skills.Teacher social-behavioral factors (e.g. self-esteem) have been foundto impact learning and teaching, and a key part of CS curriculumimplementation will need to ensure teachers feel confident to de-liver CS. However, studies about CS teacher self-esteem are lacking.This paper presents an analysis of publicly available data (n=219)from a pilot study using a Teacher CS Self-Esteem scale. Analy-sis revealed significant differences, including 1) females reportedsignificantly lower CS self-esteem than males, 2) primary teachersreported lower levels of CS self-esteem than secondary teachers, 3)those with no CS teaching experience reported significantly lowerCS self-esteem, 4) teachers with 0-3 years experience had a neg-ative CS self-esteem, but after four years, teachers had a positiveCS self-esteem, and 5) teachers who lived further from metropol-itan areas and in some countries reported lower CS self-esteem.These initial findings suggest a pressing need for future researchto look further into teacher CS self-esteem to inform teacher CSprofessional development
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