41 research outputs found
Antimikrobno djelovanje derivata 3-hidroksi-2-metilen-3-fenilpropionske kiseline
Twenty Baylis-Hillman adducts were synthesized from different aromatic aldehydes and activated vinyl derivatives. The adducts, which are differently substituted 3-hydroxy-2-methylene-3-phenylpropionic acid derivatives, were screened for their antimicrobial activity in vitro by the serial dilution method. Many of these molecules displayed potent antibacterial and antifungal activities. The ease of synthesis from low-cost starting materials along with potent antimicrobial activity of these molecules provide the lead for further improvement of activity and reflect the possibility of therapeutic use.Iz različitih aromatskih aldehida i aktiviranih vinil derivata sintetizirano je dvadeset Baylis-Hillmanovih adukata, različito supstituiranih derivata 3-hidroksi-2-metilen-3-fenilpropionske kiseline. Ispitano je njihovo antimikrobno djelovanje in vitro metodom serijskih razrjeđenja. Većina ispitivanih spojeva pokazala je snažno antibakterijsko i antifungalno djelovanje. Jednostavni sintetski postupak iz jeftinih sirovina i snažno antimikrobno djelovanje pružaju vodeće spojeve za daljnju modifikaciju, koji mogu dovesti do ljekovitih tvari pogodnih za terapijsku primjenu
Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.
BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700
Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites
The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions.
The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness
of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence
were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density
and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that
the wood in the starch composites did not prevent water loss from the samples.Peer reviewe
NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics
Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset
Evolução da pesquisa epidemiológica em atividade física no Brasil: revisão sistemática
Adoção da modularidade em produto e em produção na indústria automotiva: uma análise comparativa em projetos de veículos com participação da engenharia brasileira
Impact of protein tyrosine kinase 6 (PTK6) on human epidermal growth factor receptor (HER) signalling in breast cancer.
PTK6, also known as Brk, is highly expressed in over 80% of breast cancers. In the last decade several substrates and interaction partners were identified localising PTK6 downstream of HER receptors. PTK6 seems to be involved in progression of breast tumours, in particular in HER receptor signalling. Here, we show the down-regulation effects of PTK6 in the T47D, BT474 and JIMT-1 breast cancer cell lines. PTK6 knockdown leads to a decreased phosphorylation of HER2, PTEN, MAPK (ERK), p38 MAPK, STAT3 and to a reduced expression of cyclin E. Our findings show that silencing PTK6 impairs the downstream targets of HER receptors and consequently the activation of signalling molecules. Furthermore, lower levels of PTK6 result in reduced migration of T47D and JIMT-1 breast cancer cells. Due to decreased migration, the PTK6 RNA interference might contribute to reduced metastasis and malignant potential of breast cancer cells. Since PTK6 plays an important role in HER receptor signal transduction, its down-regulation might be suitable for future therapy approaches in breast cancer
Molecular changes in radiation induced thyroid carcinomas in mice.
Thyroid carcinomas arising from follicular epithelial cells are the most common endocrine malignancy in man. During studies performed on the population of the Marshall-Islands and after the accident at the Chernobyl nuclear power plant in 1986 a large increase in benign thyroid nodules and thyroid cancer, especially among children was shown. Thyroid follicular carcinomas are categorised into 3 histotypes: papillary, follicular, and undifferentiated (anaplastic). Papillary thyroid carcinomas are the predominant type of the thyroid cancer in patients exposed to external radiation, particularly in children. The classic oncogenic genetic alterations commonly seen in thyroid cancer include RET/PTC rearrangements, Ras point-mutations, PAX8-peroxisome proliferator-activated receptor γ (PPARg) fusion oncogene and BRAF mutation. For some families that share the FNMTC syndrome (familiar follicular nonmedullary thyroid carcinoma) a predisposition to thyroid tumors has been described. The genes responsible for FNMTC have been identified through linkage analyses of the affected families, TCO (thyroid tumors with cell oxyphilia), PRN1, and NHTC1. This study investigates gene changes in radiation induced follicular thyroid carcinoma. Following low dose exposure of the thyroid by off-targeted irradiation of the alpha-emitter 227Thorium, 5 cases of Follicular thyroid carcinomas (FTC) and 1 case of thyroid hyperplasia developed in a highly susceptible mouse strain. In such cases, Comparative Genomic Hybridization (CGH) for numerical changes was performed on the whole genome. Copy number loss affecting the entire chromosome 14 in 3 out of 6 cases was observed. A similar pattern of chromosome 14 deletions was already reported in thyroid tumours of other mouse strains following high-dose exposure or oncogene activation and therefore suggests that this deletion is not associated with genetic predisposition in different mouse strains to thyroid tumourigenesis
The <em>Rb1</em> tumour suppressor gene modifies telomeric chromatin architecture by regulating TERRA expression.
The tumour suppressor gene (Rb1) is necessary for the maintenance of telomere integrity in osteoblastic cells. We now show that the compaction of telomeric chromatin and the appropriate histone modifications of telomeric DNA are both dependent upon Rb1-mediated transcription of the telomere-derived long non-coding RNA TERRA. Expression of TERRA was reduced in Rb1 haploinsufficient cells, and further decreased by shRNA-mediated reduction of residual Rb1 expression. Restoration of Rb1 levels through lentiviral transduction was sufficient to reestablish both transcription of TERRA and condensation of telomeric chromatin. The human chromosome 15q TERRA promoter contains predicted retinoblastoma control elements, and was able to confer Rb1-dependent transcription upon a promoterless reporter gene. Chromatin immunoprecipitation revealed preferential binding of phosphorylated over non-phosphorylated Rb1 at the TERRA promoter. As Rb1-deficient cells show increased genomic instability we suggest that this novel non-canonical action of Rb1 may contribute to the tumour suppressive actions of Rb1
Secondary radiation-induced bone tumours demonstrate a high degree of genomic instability predictive of a poor prognosis.
Secondary bone tumours arising in the field of a preceding radiotherapy are a serious late effect, in particular considering the increasing survival times in patients treated for paediatric malignancies. In general, therapy associated tumours are known to show a more aggressive behaviour and a limited response to chemotherapy compared with their primary counterparts. It is not clear however whether this less favourable outcome is caused by inherent genetic factors of the tumour cells or by a general systemic condition of the patient. To elucidate this we analysed a series of bone sarcomas with a history of prior irradiation for the presence of genomic alterations and compared them with the alterations identified earlier in primary osteosarcomas. We analysed seven radiation induced bone sarcomas for genome-wide losses of heterozygosity (LOH) using Affymetrix 10K2 high-density single nucleotide polymorphism (SNP) arrays. Additionally, copy number changes were analysed at two distinct loci on 10q that were recently found to be of major prognostic significance in primary osteosarcomas. All the investigated tumours showed a LOH at 10q21.1 with 86% of cases (6/7) revealing a total genome-wide LOH score above 2400 and more than 24% of the genome being affected. Our results indicate similar genetic alterations in radiation induced sarcomas of bone and primary osteosarcomas with a poor prognosis. We speculate that the high degree of genomic instability found in these tumours causes the poor prognosis irrespective of the initiating event