Factors determining microbial colonization of liquid nitrogen storage tanks used for archiving biological samples

The availability of bioresources is a precondition for life science research, medical applications, and diagnostics, but requires a dedicated quality management to guarantee reliable and safe storage. Anecdotal reports of bacterial isolates and sample contamination indicate that organisms may persist in liquid nitrogen (LN) storage tanks. To evaluate the safety status of cryocollections, we systematically screened organisms in the LN phase and in ice layers covering inner surfaces of storage tanks maintained in different biobanking facilities. We applied a culture-independent approach combining cell detection by epifluorescence microscopy with the amplification of group-specific marker genes and high-throughput sequencing of bacterial ribosomal genes. In the LN phase, neither cells nor bacterial 16S rRNA gene copy numbers were detectable (detection limit, 102 cells per ml, 103 gene copies per ml). In several cases, small numbers of bacteria of up to 104 cells per ml and up to 106 gene copies per ml, as well as Mycoplasma, or fungi were detected in the ice phase formed underneath the lids or accumulated at the bottom. The bacteria most likely originated from the stored materials themselves (Elizabethingia, Janthibacterium), the technical environment (Pseudomonas, Acinetobacter, Methylobacterium), or the human microbiome (Bacteroides, Streptococcus, Staphylococcus). In single cases, bacteria, Mycoplasma, fungi, and human cells were detected in the debris at the bottom of the storage tanks. In conclusion, the limited microbial load of the ice phase and in the debris of storage tanks can be effectively avoided by minimizing ice formation and by employing hermetically sealed sample containers

Efeitos da nutrição parenteral total associada à infecção bacteriana na função hepatobiliar de ratos da cepa Wistar

OBJECTIVE: To evaluate the hepatic alterations associated to parenteral nutrition inrats.MATERIAL AND METHODS: Four groups with 10 rats each: Group I (control group) -rats were orally fed with a regular diet; Group II - rats received a regular diet, and wereinfected with Escherichia coli through intraperitoneal inoculation; Group III - rats receivedparenteral nutrition; and group IV, rats received parenteral nutrition, and were infectedwith Escherichia coli. Serum concentrations of AST, ALT, GGT, and 5’ N were measuredon the first day of the experiment, and on the eighth day of parenteral nutrition (the dayanimals were sacrificed). Histological study of the liver of the rats included: evaluationof hydropic degeneration, dilation of the central lobular vein, cholestasis, sinusoidaldilation, proliferation of Kupffer cells, cellular necrosis, and steatosis. All alterationswere graded from 0 to 4+.RESULTS: The lab exams did not present consistent alterations at the end of theexperiment. Group IV presented a reduction in GGT concentration; in addition, thisgroup presented the largest variations in AST and ALT concentration, possibly as aresult of being submitted to more intense aggression to the hepatic parenchyma. Froma histological point-of-view, all animals (with the exception of one) presented dilation ofthe central lobular vein and of the sinusoids. Such findings were more frequent amonginfected animals. The animals did not present steatosis or cholestasis.CONCLUSIONS: 1) The proposed model of intraperitoneal inoculation of Escherichiacoli was appropriate for the study of bacterial infection in young rats of the Wistarstrain; 2) our results indicate that the association of parenteral nutrition and infectiondetermined histologic alterations which were unspecific, but more intense than thealterations determined by each of these situations in isolation.OBJETIVO: Avaliar as alterações hepáticas associadas à nutrição parenteral em ratos.MATERIAIS E MÉTODOS: Foram avaliados quatro grupos com 10 ratos cada: grupoI - controles alimentados, via oral, com dieta habitual; grupo II - em dieta habitual einfectados com Escherichia Coli inoculada por via intra peritoneal; grupo III - emnutrição parenteral; e grupo IV - em nutrição parenteral e infectados. Foram analisadasas concentrações séricas de AST, ALT, GGT e 5’N no primeiro dia do experimento eno oitavo dia da nutrição parenteral, por ocasião do sacrifício dos animais. O estudohistológico do fígado dos 40 ratos consistiu na avaliação de degeneração hidrópica,dilatação da veia centro-lobular, colestase, dilatação sinusoidal, proliferação de célulasde Kupffer, necrose celular e esteatose. As alterações foram graduadas de 0 a 4+.RESULTADOS: Os exames laboratoriais não foram consistentemente alterados aofinal do experimento. No grupo IV houve redução na concentração de GGT; alémdisso, este foi o grupo que apresentou as maiores variações de AST e ALT,possivelmente devido à maior agressão do parênquima hepático. Do ponto de vistahistológico, todos os animais submetidos à nutrição parenteral (com apenas umaexceção) apresentaram dilatação da veia centro-lobular e dos sinusóides. Estesachados foram mais comuns nos animais infectados. Não foram observadas esteatosee/ou colestase.CONCLUSÕES: 1) O modelo proposto de inoculação intra-peritoneal com EscherichiaColi foi adequado para estudar infecção em ratos jovens da cepa Wistar; 2) osresultados obtidos indicaram que a associação entre nutrição parenteral e infecçãodeterminou alterações histológicas inespecíficas, porém mais intensas do que asalterações determinadas em cada uma dessas situações isoladamente

Modification of the method for assessing the fire hazards in areas of coal mining wastes locating

W artykule zaproponowano modyfikację metody oceny zagrożenia pożarowego na terenach lokowania odpadów powęglowych. Metoda pierwotna została opracowana w Głównym Instytucie Górnictwa w latach 80. XX w. i zmodyfikowana w 1996 r. Wprowadzone zmiany zmierzały do uproszczenia istniejącej już metody. Dostosowano ją do obecnych możliwości technicznych w zakresie badań parametrów określających stan termiczny obiektów formowanych z odpadów powęglowych. Ważny aspekt stanowiły także warunki techniczne omawianej metody, obejmujące ocenę jakości prowadzonych robót. W tak zmodyfikowanej metodzie najważniejszymi kryteriami oceny zagrożenia pożarowego są: - zakres i częstotliwość badań stanu termicznego obiektu, - ocena wskaźnika zagęszczenia uformowanych nasypów.In the article, the modification of the method for assessing the fire hazards in areas of coal mining wastes locating has been proposed. The primal method was developed in the Central Mining Institute (Główny Instytut Górnictwa) in the 1980s of the 20th century and modified in 1996. The aim of the undertaken changes has been to simplify the already existing method. It has been adapted to the current technical possibilities in the field of the research parameters defining the thermal state of objects formed from mining waste. As the important aspect the technical conditions of this method have also been stated, including the assessment of the quality of the carried out works. In the method modified in this way, the major fire hazard assessment criteria have been regarded as: - the scope and frequency of tests on thermal state of an object, - the evaluation of the indicator of the formed embankments density

Plantation of energy willow on demoted post coalmine area

Celem pracy było zbadanie możliwości upraw roślin energetycznych na terenach zdegradowanych, na przykładzie wierzby wiciowej. Pracę zrealizowano badając możliwość uprawy wierzby na terenie zrekultywowanego składowiska kamienia "Wschód I" KWK Mysłowice. Zakres pracy obejmował wykonanie badań zagęszczenia oraz badań chemicznych gruntu, następnie wykonanie poletek doświadczalnych pod uprawę wierzby oraz nasadzenie i obserwację wzrostu roślin. Nasadzono ponad 900 sadzonek wierzby Salix viminalis w dwóch turach: jesienią oraz wiosną. Przyjęta technika nasadzeń obejmowała nasadzenia bezpośrednio w materiale hałdowym, w dołkach zaprawionych ustabilizowanymi osadami ściekowymi oraz w tzw. warstwie uzdatnionej (wymieszana wierzchnia warstwa materiału hałdowego z osadami ściekowymi). Stwierdzono, że znacznie lepsze wyniki dają nasadzenia jesienne w porównaniu z nasadzeniami wiosennymi, o czym świadczyła zarówno liczba sadzonek, które się przyjęły, jak i szybkość ich wzrostu. Jednak niedostateczna wilgotność gruntu wykluczała odpowiedni przyrost masy (porównywalny z przyrostem na terenach rolnych) - zapewniający opłacalność ekonomiczną plantacji. Polepszenie wielkości plonów upraw lokalizowanych na obszarach lokowania odpadów powęglowych może być zapewnione przez wybór terenu zapewniającego odpowiednią retencję wód, a także stworzenie "warstwy urodzajnej", na przykład przez zastosowanie komunalnych osadów ściekowych.The purpose of the work was testing of the plantation of energy willow on the demoted post coalmine ground of Mysłowice colliery. In the scope of the work density and chemistry of ground were investigated, the experimental patches were prepared and the willow was planted and its growth observed. Over 900 of the willow cuttings were planted in two periods, in autumn and in spring. The plantation was performed in three ways: directly in the ground not specially prepared, in the soil prepared by adding a stabilised sewage fertiliser and in the special prepared soil which was the mixture of original soil and stabilised sewage fertiliser. The results show that the much better season for plantation is autumn when enough moisture in soil is available for the first period of vegetation. In the autumn plantation successfully have grown more cuttings to compare with the spring plantation. However not enough moisture content in the ground made that the vegetation is much slower to compare with arable grounds and is not economical. Better results may be achieved by choosing the ground with proper water retention and by preparing the soil for example by using stabilised sewage fertiliser

Influence of anti-pyrogenic materials on coal mining waste's tendency to self-ignite

The aim of this work was to investigate the influence of anti-pyrogenic materials with use of Combustion By-Products (CBP) on the tendency of coal mining waste to self-ignite in laboratory conditions. The tested material sample was a mixture of coal waste with an addition of anti-pyrogenic material based on coal combustion by-products. The laboratory installation to test the properties of anti-pyrogenic materials is presented. The temperature of the tested sample as well as the concentration of carbon monoxide in exhaust gas were chosen as the parameters which determine the properties of anti-pyrogenic materials to reduce the self-heating process of coal waste. Laboratory tests of material samples were performed in a temperature range from 40°C to 500°C, at time interval of 350 s

Tests and evaluation of effectiveness of mixtures mitigating mercury vapour emission from mine waste dumps

W artykule przedstawiono wyniki badań laboratoryjnych i terenowych, których głównym celem było opracowanie składu mieszanin ograniczających procesy uwalniania się rtęci do środowiska naturalnego z hałd odpadów powęglowych oraz opracowanie metodyki jej trwałego wiązania (absorpcji). W prowadzonych pracach wykorzystano materiały odpadowe z energetyki, górnictwa węgla kamiennego i górnictwa gazu ziemnego. Opracowane mieszaniny do redukcji emisji par rtęci poddane zostały badaniom laboratoryjnym oraz badaniom in situ na zapożarowanej hałdzie odpadów powęglowych, w celu oceny ich skuteczności. Jako miarę skuteczności przyjęto względny spadek emisji powierzchniowej par rtęci związany z wykonaniem warstw absorpcyjno-izolujących z opracowanych mieszanin.This paper presents the results of laboratory tests and field research whose main objective was to develop the composition of mixtures mitigating processes of mercury release to the environment from mine waste dumps, and to develop a methodology for its permanent bonding (absorption). In the ongoing work we use waste materials from energy, coal mining and natural gas mining. The developed mixture to reduce emissions of mercury vapours were subject to laboratory tests and studies in situ on the heap of coal wastes with the risk of spontaneous combustion in order to evaluate effectiveness of this mixture. As a measure of efficacy, the relative decrease in the surface of the mercury vapor emissions, associated with the implementation of an absorption-insulating layers of the prepared mixtures, was assumed