407 research outputs found
PARP1 ADP-ribosylates lysine residues of the core histone tails
The chromatin-associated enzyme PARP1 has previously been suggested to ADP-ribosylate histones, but the specific ADP-ribose acceptor sites have remained enigmatic. Here, we show that PARP1 covalently ADP-ribosylates the amino-terminal histone tails of all core histones. Using biochemical tools and novel electron transfer dissociation mass spectrometric protocols, we identify for the first time K13 of H2A, K30 of H2B, K27 and K37 of H3, as well as K16 of H4 as ADP-ribose acceptor sites. Multiple explicit water molecular dynamics simulations of the H4 tail peptide into the catalytic cleft of PARP1 indicate that two stable intermolecular salt bridges hold the peptide in an orientation that allows K16 ADP-ribosylation. Consistent with a functional cross-talk between ADP-ribosylation and other histone tail modifications, acetylation of H4K16 inhibits ADP-ribosylation by PARP1. Taken together, our computational and experimental results provide strong evidence that PARP1 modifies important regulatory lysines of the core histone tail
Immunohistochemical investigations and introduction of new therapeutic strategies in scleromyxoedema: Case report
BACKGROUND: Scleromyxoedema is a rare chronic skin disease of obscure origin, which may often be associated with severe internal co-morbidity. Even though different casuistic treatment modalities have been described, to date, curing still seems to be impossible. CASE PRESENTATION: We report a 44-year-old Caucasian female presenting with remarkable circumscribed, erythematous to skin-coloured, indurated skin eruptions at the forehead, arms, shoulders, legs and the gluteal region. Routine histology and Alcian blue labelling confirmed a massive deposition of acid mucopolysaccharides. Immunohistochemical investigations revealed proliferating fibroblasts and a discrete lymphocytic infiltration as well as increased dermal expression of MIB-1(+ )and anti-mastcell-tryptase(+ )cells. Bone marrow biopsies confirmed a monoclonal gammopathy of undetermined significance without morphological characteristics of plasmocytoma; immunofixation unveiled the presence of IgG-kappa paraproteins. CONCLUSIONS: Taking all data into account, our patient exhibited a complex form of lichen mxyoedematosus, which could most likely be linked a variant of scleromyxoedema. Experimental treatment with methotrexate resulted in a stabilisation of clinical symptoms but no improvement after five months of therapy. A subsequent therapeutic attempt by the use of medium-dose ultraviolet A1 cold-light photomonotherapy led to a further stabilisation of clinical symptoms, but could not induce a sustained amelioration of skin condition
Impact of UVA exposure on psychological parameters and circulating serotonin and melatonin
BACKGROUND: People tend to feel better after exposure to ultraviolet (UV) radiation. This study was performed to investigate the impact of UVA exposure on psychological and neuroendocrine parameters. METHODS: Fifty-three volunteers were separated into 42 individuals who had UVA exposure and 11 individuals who had no UVA exposure. The UVA-exposed volunteers had irradiation sessions six times in a three-week period. All volunteers completed two questionnaires at baseline (T1) and at the end of the study (T3). For the determination of serotonin and melatonin serum levels of all volunteers blood samples were collected at baseline (T1), after the first UVA exposure (T2), and at the end of the study after the sixth exposure (T3). RESULTS: UVA-exposed volunteers felt significantly more balanced, less nervous, more strengthened, and more satisfied with their appearance at T3. By contrast, the controls did not show significant changes of psychological parameters. In comparison to T1 and T3, serum serotonin was significantly higher and the serum melatonin was significantly lower for the volunteers exposed to UVA at T2. Both, for exposed and non-exposed volunteers serotonin and melatonin levels did not significantly differ at T1 and T3. CONCLUSIONS: It remains obscure, whether the exposure to UVA or other components of the treatment were responsible for the psychological benefits observed. The changes of circulating neuroendocrine mediators found after UVA exposure at T2 may be due to an UVA-induced effect via a cutaneous pathway. Nevertheless, the positive psychological effects observed in our study cannot be attributed to circulating serotonin or melatonin
Analysis of the PARP1, ADP-Ribosylation, and TRIP12 Triad With Markers of Patient Outcome in Human Breast Cancer
PARP inhibitors (PARPi) are increasingly used in breast cancer therapy, including high-grade triple-negative breast cancer (TNBC) treatment. Varying treatment responses and PARPi resistance with relapse currently limit the efficacy of PARPi therapy. The pathobiological reasons why individual patients respond differently to PARPi are poorly understood. In this study, we analyzed the expression of PARP1, the main target of PARPi, in normal breast tissue, breast cancer, and its precursor lesions using human breast cancer tissue microarrays covering a total of 824 patients, including more than 100 TNBC cases. In parallel, we analyzed nuclear adenosine diphosphate (ADP)-ribosylation as a marker of PARP1 activity and TRIP12, an antagonist of PARPi-induced PARP1 trapping. Although we found PARP1 expression generally increased in invasive breast cancer, PARP1 protein levels and nuclear ADP-ribosylation were lower in higher tumor grade and TNBC samples than non-TNBCs. Cancers with low levels of PARP1 and low levels of nuclear ADP-ribosylation were associated with significantly reduced overall survival. This effect was even more pronounced in cases with high levels of TRIP12. These results indicate that PARP1-dependent DNA repair capacity may be compromised in aggressive breast cancers, potentially fueling enhanced accumulation of mutations. Moreover, the results revealed a subset of breast cancers with low PARP1, low nuclear ADP-ribosylation, and high TRIP12 levels, which may compromise their response to PARPi, suggesting a combination of markers for PARP1 abundance, enzymatic activity, and trapping capabilities might aid patient stratification for PARPi therapy
Дослідження структури порушених відкритою розробкою земель й пошук шляхів вдосконалення рекультивації залишкових виробок кар'єрів
Стаття присвячена дослідженням структури порушених земель, на ділянках з видобутку корисних копалин відкритим способом. Наведено площі порушень земель при розробці основних видів корисних копалин. Проаналізовано ризики, що виникають із несвоєчасною рекультивацією земель гірничого відводу, а також від покинутих гірничих виробок старих кар'єрів. Паралельно розглянуті обсяги відходів гірничого виробництва та їх повторне використання в якості заповнювача для залишкових вироблених просторів кар'єрів.The article is devoted to the research of land violation indicators at the extraction of minerals by surface mining method. Data gives about the land violations area at the mining key minerals. Ana-lyzed the risks from the not-on-time reclamation of the mining clam and abandoned excavations of the old quarries. In parallel considered the volumes of mining wastes and their reuse as aggregate for filling residual spaces of surface mines.Статья посвящена исследованиям площадей нарушения земель, связанных с добычей полезных ископаемых открытым способом. Приведены площади нарушений земель при разработке основных видов полезных ископаемых. Проанализированы риски, представляемые несвоевременной рекультивацией земель горного отвода, а также заброшенными горными выработками старых карьеров. Параллельно рассмотрены объемы отходов горного производства и их повторное использование в качестве заполнителя для остаточных выработанных пространств карьеров
Task-Set Generator for Schedulability Analysis using the TACLeBench benchmark suite
ABSTRACT Current real-time embedded systems evolve towards complex systems using new state of the art technologies such as multi-core processors and virtualization techniques. Both technologies requires new real-time scheduling algorithms. For uniprocessor scheduling, utilization-based evaluation methodologies are common and well-established. For multicore systems and virtualization, evaluating and comparing scheduling techniques using the tasks' parameters is more realistic. Evaluating these different scheduling techniques requires relevant and standardised task sets. Scheduling algorithms can be evaluated on three evaluation levels: 1) by using the mathematical model of the scheduling algorithm, 2) by simulating the scheduling algorithm and 3) by implementing the algorithm on the target platform. Generating task sets is straightforward in case of the first two levels; only the parameters of the tasks are required. Evaluating and comparing scheduling algorithms on the target platform itself, however, requires real executable tasks matching the predefined standardised task sets. Generating those executable tasks is not standardized yet. Therefore, we developed a task-set generator that generates reproducible, standardised task sets that are suitable at all levels. Beside generating the tasks' parameters, it includes an executable generator methodology that generates executables by combining publicly available benchmarks with know execution times. This paper presents and evaluates this task-set generator. The executables approximate the wanted execution time on the hardware platform
Protection against ultraviolet radiation by commercial summer clothing: need for standardised testing and labelling
BACKGROUND: The use of clothing as a means of sun protection has been recommended in recent education campaigns. Contrary to popular opinion, however, some fabrics provide insufficient ultraviolet (UV) protection. MATERIAL AND METHODS: We investigated 236 apparel textiles of the spring/summer collections 2000 and 2001. In accordance with the forthcoming European standard the UV protection factor (UPF) of the fabrics was determined spectrophotometrically. RESULTS: Seventy-eight (33%) fabrics had UPF < 15, 45 (19%) had UPF = or > 15 and < 30, and 113 (48%) had UPF = or > 30 (30+). More than 70% of the wool, polyester, and fabric blends, and only less than 30% of the cotton, linen, and viscose fabrics had UPF values of 30+. Fabrics with black, navy-blue, white, green, or beige colours provided most frequently UPF values of 30+. CONCLUSIONS: It is difficult for the sun-aware consumer to choose the 'right' garment, with a third of summer clothing providing insufficient UV protection and only half of the fabrics having UPF 30+, the UPF recommended by the European standard. Therefore, apparel summer fabrics should be measured and labelled in accordance with a standard document
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