Ázsiai orrszarvúak a Magyar Természettudományi Múzeum gyűjteményében = Asian rhinos in the Hungarian Natural History Museum

Descriptions of a Sumatran rhinoceros Dicerorhinus sumatrensis and a Javan rhinoceros Rhinoceros sondaicus specimen, housed in the Hungarian Natural History Museum are given. The Sumatran rhinoceros was probably captured in Peninsular Malaysia in 1894 and purchased by the Municipal Botanical and Zoological Gardens, Budapest, Hungary, whereas the Javan rhinoceros was shot by J. Xántus Hungarian explorer in Java in 1869. Both were later donated to the Hungarian Natural History Museum where they are preserved as mounted specimens and some bones. With 6 figure

Mathematical modelling of cylindrical chimney effect in solar dryer

A simple mathematical model of a solar chimney is proposed for the solar dryer. The physical model was made with a cylindrical channel. Outer surface of the chimney is provided with black paint which absorbing solar radiation to heat up the air inside the chimney. Openings provided at the bottom and top of the chimney allow moist air to enter from the drying chamber and leave the channel. Steady state heat transfer equations were set determining the heat transfer coefficient and the air flow in the chimney. The thermal performance of the solar chimney as determined from the surfaces, air temperatures, and air mass flow rate are presented

A vállalati vagyon és a finanszírozás összefüggései a vagyonértékelés szempontrendszere szerint

The availability for financial sources can be the key factor of competitiveness of enterprises. Under favourable conditions it can result in not only economic growth and conjunctural effects but indirectly it also has a positive influence on social level as well. In the first part of the article we make an overview on enterprise financing in both social and economic context and try to give an overall concept. In the second part we analyse the framework of financing, discuss the national and international specifications of financing, and finally, in the third part we analyse the background of enterprise financing based on the principles of asset appraisal.A finanszírozási forrásokhoz való hozzáférés a vállalati szféra versenyképességének kulcstényezőjét jelenti, kedvező feltételek mellett nem csak gazdasági növekedést és konjunkturális hatásokat eredményezhet, hanem közvetetten a társadalmi folyamatokat is pozitívan befolyásolja. A cikk első részében a vállalati finanaszírozás fontosabb jellemzőit tekintjük át gazdasági és társadalmi összefüggésben, törekedve a finanszírozási viszonyok átfogó szemléjére. A cikk második részében a finanszírozás szabálykeretét tekintjük át a vonatkozó nemzetközi és hazai előírások tárgyalásával, a harmadik részben pedig a vállalati finanszírozás hátterét elemezzük a vagyonértékelői gyakorlat és szempontrendszer alapján

Unique patterns of CD8+ T-cell-mediated organ damage in the Act-mOVA/OT-I model of acute graft-versus-host disease.

T-cell receptor (TCR)-transgenic models of acute graft-versus-host disease (aGvHD) offer a straightforward and highly controlled approach to study the mechanisms and consequences of T-cell activation following allogeneic hematopoietic stem cell transplantation (aHSCT). Here, we report that aHSCT involving OT-I mice as donors, carrying an ovalbumin-specific CD8+ TCR, and Act-mOVA mice as recipients, expressing membrane-bound ovalbumin driven by the β-actin promoter, induces lethal aGvHD in a CD8+ T-cell-dependent, highly reproducible manner, within 4-7 days. Tracking of UBC-GFP/OT-I graft CD8+ T cells disclosed heavy infiltration of the gastrointestinal tract, liver, and lungs at the onset of the disease, and histology confirmed hallmark features of gastrointestinal aGVHD, hepatic aGvHD, and aGvHD-associated lymphocytic bronchitis in infiltrated organs. However, T-cell infiltration was virtually absent in the skin, a key target organ of human aGvHD, and histology confirmed the absence of cutaneous aGVHD, as well. We show that the model allows studying CD8+ T-cell responses in situ, as selective recovery of graft CD45.1/OT-I CD8+ T cells from target organs is simple and feasible by automated tissue dissociation and subsequent cell sorting. Assessment of interferon-gamma production by flow cytometry, granzyme-B release by ELISA, TREC assay, and whole-genome gene expression profiling confirmed that isolated graft CD8+ T cells remained intact, underwent clonal expansion, and exerted effector functions in all affected tissues. Taken together, these data demonstrate that the OT-I/Act-mOVA model is suitable to study the CD8+ T-cell-mediated effector mechanisms in a disease closely resembling fatal human gastrointestinal and hepatic aGVHD that may develop after aHSCT using HLA-matched unrelated donors

Antibiotic-induced release of small extracellular vesicles (exosomes) with surface-associated DNA

Recently, biological roles of extracellular vesicles (which include among others exosomes, microvesicles and apoptotic bodies) have attracted substantial attention in various fields of biomedicine. Here we investigated the impact of sustained exposure of cells to the fluoroquinolone antibiotic ciprofloxacin on the released extracellular vesicles. Ciprofloxacin is widely used in humans against bacterial infections as well as in cell cultures against Mycoplasma contamination. However, ciprofloxacin is an inducer of oxidative stress and mitochondrial dysfunction of mammalian cells. Unexpectedly, here we found that ciprofloxacin induced the release of both DNA (mitochondrial and chromosomal sequences) and DNA-binding proteins on the exofacial surfaces of small extracellular vesicles referred to in this paper as exosomes. Furthermore, a label-free optical biosensor analysis revealed DNA-dependent binding of exosomes to fibronectin. DNA release on the surface of exosomes was not affected any further by cellular activation or apoptosis induction. Our results reveal for the first time that prolonged low-dose ciprofloxacin exposure leads to the release of DNA associated with the external surface of exosomes

Isolation of Exosomes from Blood Plasma: Qualitative and Quantitative Comparison of Ultracentrifugation and Size Exclusion Chromatography Methods

BACKGROUND: Exosomes are emerging targets for biomedical research. However, suitable methods for the isolation of blood plasma-derived exosomes without impurities have not yet been described. AIM: Therefore, we investigated the efficiency and purity of exosomes isolated with potentially suitable methods; differential ultracentrifugation (UC) and size exclusion chromatography (SEC). METHODS AND RESULTS: Exosomes were isolated from rat and human blood plasma by various UC and SEC conditions. Efficiency was investigated at serial UC of the supernatant, while in case of SEC by comparing the content of exosomal markers of various fractions. Purity was assessed based on the presence of albumin. We found that the diameter of the majority of isolated particles fell into the size range of exosomes, however, albumin was also present in the preparations, when 1h UC at 4 degrees C was applied. Furthermore, with this method only a minor fraction of total exosomes could be isolated from blood as deduced from the constant amount of exosomal markers CD63 and TSG101 detected after serial UC of rat blood plasma samples. By using UC for longer time or with shorter sedimentation distance at 4 degrees C, or UC performed at 37 degrees C, exosomal yield increased, but albumin impurity was still observed in the isolates, as assessed by transmission electron microscopy, dynamic light scattering and immunoblotting against CD63, TSG101 and albumin. Efficiency and purity were not different in case of using further diluted samples. By using SEC with different columns, we have found that although a minor fraction of exosomes can be isolated without significant albumin content on Sepharose CL-4B or Sephacryl S-400 columns, but not on Sepharose 2B columns, the majority of exosomes co-eluted with albumin. CONCLUSION: Here we show that it is feasible to isolate exosomes from blood plasma by SEC without significant albumin contamination albeit with low vesicle yield