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731.
Fischbach J Gut P Matysiak-Grześ M Klimowicz A Gryczyńska M Waśko R Ruchała M 《Neuro endocrinology letters》2012,33(3):273-278
BACKGROUND: Insulinomas are the most common functioning neuroendocrine tumours of the pancreas. Hypoglycemia due to excessive production of insulin is a main feature of this disease. Usually these neoplasms are benign and single with surgical excision as a treatment of choice. About 10% are malignant with tendency to form metastases especially to the liver then therapy requires various medical technics. CASE REPORT: 43 years old female with reccurent syncopies in course of hypoglycemia was admitted to the hospital to be diagnosed. Having suspected pathology within the pancreas the abdominal MRI was performed. It showed presence of numerous metastatic changes in the liver with no any other deviations in the abdomen including pancreas. Subsequent 18FDG PET-CT revealed metastases to the regional lymph nodes and the liver and suggested the presence of a primary lesion in the tail of the pancreas which was confirmed in EUS. Surgical excision of the tail of the pancreas was done. Pathological result: pancreatic neuroendocrine well differetiated cancer. Due to the recurrence of hypoglycemia patient was admitted to Department of Endocrinology where somatostatin analogue scintigraphy showed the presence of tracer accumulation foci in the liver. Combined long-acting somatostatin analogue (octreotide) and peptide radionuclide receptor ((90)Y-DOTA-TATE) therapy were introduced. Stable blood glucose levels with no tendency to hypoglycemia and partial regression (PR) of liver lesions according to RECIST citeria were observed in course of the treatment. 相似文献
732.
Population biobanks offer new opportunities for public health, are rudimentary for the development of its new branch called
Public Health Genomics, and are important for translational research. This article presents organizational models of population
biobanks in selected European countries. Review of bibliography and websites of European population biobanks (UK, Spain, Estonia).
Some countries establish national genomic biobanks (DNA banks) in order to conduct research on new methods of prevention,
diagnosis and treatment of the genetic and lifestyle diseases and on pharmacogenetic research. Individual countries have developed
different organizational models of these institutions and specific legal regulations regarding various ways of obtaining genetic
data from the inhabitants, donors’ rights, organizational and legal aspects. Population biobanks in European countries were
funded in different manners. In light of these solutions, the authors discuss prospects of establishing a Polish national
genomic biobank for research purpose. They propose the creation of such an institution based on the existing network of blood-donation
centres and clinical biobanks in Poland. 相似文献
733.
Pohanka M Pavlis O Ruttkay-Nedecky B Sochor J Sobotka J Pikula J Adam V Kizek R 《Journal of microbiology (Seoul, Korea)》2012,50(3):401-408
Francisella tularensis is the causative agent of tularemia. It is an intracellular pathogen with the ability to survive within phagosomes and induce pyroptotic cell death. In this study, we attempted to prove whether oxidative imbalance plays a significant role in tularemia pathogenesis. In our experimental model, we subcutaneously infected female BALB/c mice (dose 10(5) CFU of F. tularensis LVS). Liver, spleen, and blood were collected from mice at regular intervals from days 1-15 after infection. The bacterial burden was assessed by a cultivation test. The burden was unchanging from the 2(nd) to 6(th) day after infection. The bacterial burden corresponded to the plasmatic level of IFN-γ, IL-6, and liver malondialdehyde. After the phase of acute bacteraemia and the innate immunity reaction, the levels of reduced glutathione and total low molecular weight antioxidants decreased significantly and the activity of caspase-3 increased in the liver. The level of reduced glutathione decreased to 25% of the original level, and the total level of low molecular weight antioxidants was less than 50% of the initial amount. The demonstrated effects of tularemia-induced pathology had a more extensive impact on the liver than on the spleen. 相似文献
734.
The apid cuckoo bees of the Cape Verde Islands (Republic of Cape Verde) are reviewed and five species recognized, representing two genera. The ammobatine genus Chiasmognathus Engel (Nomadinae: Ammobatini), a specialized lineage of cleptoparasites of nomioidine bees is recorded for the first time. Chiasmognathus batelkaisp. n. is distinguished from mainland African and Asian species. The genus Thyreus Panzer (Apinae: Melectini) is represented by four species - Thyreus denoliisp. n., Thyreus batelkaisp. n., Thyreus schwarzisp. n., and Thyreus aistleitnerisp. n. Previous records of Thyreus scutellaris (Fabricius) from the islands were based on misidentifications. 相似文献
735.
Jakub Nowosad 《International journal of biometeorology》2016,60(6):843-855
Corylus, Alnus, and Betula trees are among the most important sources of allergic pollen in the temperate zone of the Northern Hemisphere and have a large impact on the quality of life and productivity of allergy sufferers. Therefore, it is important to predict high pollen concentrations, both in time and space. The aim of this study was to create and evaluate spatiotemporal models for predicting high Corylus, Alnus, and Betula pollen concentration levels, based on gridded meteorological data. Aerobiological monitoring was carried out in 11 cities in Poland and gathered, depending on the site, between 2 and 16 years of measurements. According to the first allergy symptoms during exposure, a high pollen count level was established for each taxon. An optimizing probability threshold technique was used for mitigation of the problem of imbalance in the pollen concentration levels. For each taxon, the model was built using a random forest method. The study revealed the possibility of moderately reliable prediction of Corylus and highly reliable prediction of Alnus and Betula high pollen concentration levels, using preprocessed gridded meteorological data. Cumulative growing degree days and potential evaporation proved to be two of the most important predictor variables in the models. The final models predicted not only for single locations but also for continuous areas. Furthermore, the proposed modeling framework could be used to predict high pollen concentrations of Corylus, Alnus, Betula, and other taxa, and in other countries. 相似文献
736.
Equine metabolic syndrome impairs adipose stem cells osteogenic differentiation by predominance of autophagy over selective mitophagy
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Krzysztof Marycz Katarzyna Kornicka Monika Marędziak Paweł Golonka Jakub Nicpoń 《Journal of cellular and molecular medicine》2016,20(12):2384-2404
Adipose‐derived mesenchymal stem cells (ASC) hold great promise in the treatment of many disorders including musculoskeletal system, cardiovascular and/or endocrine diseases. However, the cytophysiological condition of cells, used for engraftment seems to be fundamental factor that might determine the effectiveness of clinical therapy. In this study we investigated growth kinetics, senescence, accumulation of oxidative stress factors, mitochondrial biogenesis, autophagy and osteogenic differentiation potential of ASC isolated from horses suffered from equine metabolic syndrome (EMS). We demonstrated that EMS condition impairs multipotency/pluripotency in ASCs causes accumulation of reactive oxygen species and mitochondria deterioration. We found that, cytochrome c is released from mitochondria to the cytoplasm suggesting activation of intrinsic apoptotic pathway in those cells. Moreover, we observed up‐regulation of p21 and decreased ratio of Bcl‐2/BAX. Deteriorations in mitochondria structure caused alternations in osteogenic differentiation of ASCEMS resulting in their decreased proliferation rate and reduced expression of osteogenic markers BMP‐2 and collagen type I. During osteogenic differentiation of ASCEMS, we observed autophagic turnover as probably, an alternative way to generate adenosine triphosphate and amino acids required to increased protein synthesis during differentiation. Downregulation of PGC1α, PARKIN and PDK4 in differentiated ASCEMS confirmed impairments in mitochondrial biogenesis and function. Hence, application of ASCEMS into endocrinological or ortophedical practice requires further investigation and analysis in the context of safeness of their application. 相似文献
737.
Balancing selection and genetic drift create unusual patterns of MHCIIβ variation in Galápagos mockingbirds
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Jakub Vlček Paquita E. A. Hoeck Lukas F. Keller Jessica P. Wayhart Iva Dolinová Jan Štefka 《Molecular ecology》2016,25(19):4757-4772
The extracellular subunit of the major histocompatibility complex MHCIIβ plays an important role in the recognition of pathogens and the initiation of the adaptive immune response of vertebrates. It is widely accepted that pathogen‐mediated selection in combination with neutral micro‐evolutionary forces (e.g. genetic drift) shape the diversity of MHCIIβ, but it has proved difficult to determine the relative effects of these forces. We evaluated the effect of genetic drift and balancing selection on MHCIIβ diversity in 12 small populations of Galápagos mockingbirds belonging to four different species, and one larger population of the Northern mockingbird from the continental USA. After genotyping MHCIIβ loci by high‐throughput sequencing, we applied a correlational approach to explore the relationships between MHCIIβ diversity and population size by proxy of island size. As expected when drift predominates, we found a positive effect of population size on the number of MHCIIβ alleles present in a population. However, the number of MHCIIβ alleles per individual and number of supertypes were not correlated with population size. This discrepancy points to an interesting feature of MHCIIβ diversity dynamics: some levels of diversity might be shaped by genetic drift while others are independent and possibly maintained by balancing selection. 相似文献
738.
739.
Jakub Nowosad Alfred Stach Idalia Kasprzyk Elżbieta Weryszko-Chmielewska Krystyna Piotrowska-Weryszko Małgorzata Puc Łukasz Grewling Anna Pędziszewska Agnieszka Uruska Dorota Myszkowska Kazimiera Chłopek Barbara Majkowska-Wojciechowska 《Aerobiologia》2016,32(3):453-468
The aim of the study was to create and evaluate models for predicting high levels of daily pollen concentration of Corylus, Alnus, and Betula using a spatiotemporal correlation of pollen count. For each taxon, a high pollen count level was established according to the first allergy symptoms during exposure. The dataset was divided into a training set and a test set, using a stratified random split. For each taxon and city, the model was built using a random forest method. Corylus models performed poorly. However, the study revealed the possibility of predicting with substantial accuracy the occurrence of days with high pollen concentrations of Alnus and Betula using past pollen count data from monitoring sites. These results can be used for building (1) simpler models, which require data only from aerobiological monitoring sites, and (2) combined meteorological and aerobiological models for predicting high levels of pollen concentration. 相似文献
740.
Tibor András Rokob Jakub Chalupský Daniel Bím Prokopis C. Andrikopoulos Martin Srnec Lubomír Rulíšek 《Journal of biological inorganic chemistry》2016,21(5-6):619-644
In this minireview, we provide an account of the current state-of-the-art developments in the area of mono- and binuclear non-heme enzymes (NHFe and NHFe2) and the smaller NHFe(2) synthetic models, mostly from a theoretical and computational perspective. The sheer complexity, and at the same time the beauty, of the NHFe(2) world represents a challenge for experimental as well as theoretical methods. We emphasize that the concerted progress on both theoretical and experimental side is a conditio sine qua non for future understanding, exploration and utilization of the NHFe(2) systems. After briefly discussing the current challenges and advances in the computational methodology, we review the recent spectroscopic and computational studies of NHFe(2) enzymatic and inorganic systems and highlight the correlations between various experimental data (spectroscopic, kinetic, thermodynamic, electrochemical) and computations. Throughout, we attempt to keep in mind the most fascinating and attractive phenomenon in the NHFe(2) chemistry, which is the fact that despite the strong oxidative power of many reactive intermediates, the NHFe(2) enzymes perform catalysis with high selectivity. We conclude with our personal viewpoint and hope that further developments in quantum chemistry and especially in the field of multireference wave function methods are needed to have a solid theoretical basis for the NHFe(2) studies, mostly by providing benchmarking and calibration of the computationally efficient and easy-to-use DFT methods. 相似文献