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Sample records for acquired thermotolerance heat

  1. Heat Stress Screening of Peanut Seedlings for Acquired Thermotolerance

    The objective of this research was to develop a user-friendly and medium throughput laboratory protocol using acquired thermotolerance (ATT) in peanut seedlings as a measure of one mechanism of heat stress tolerance. Sixteen genotypes, including selected accessions of the U.S. peanut min...

  2. A review of acquired thermotolerance, heat shock proteins, and molecular chaperones in archaea

    Trent, J.D.

    1996-05-01

    Acquired thermotolerance, the associated synthesis of heat-shock proteins (HSPs) under stress conditions, and the role of HSPs as molecular chaperones under normal growth conditions have been studied extensively in eukaryotes and bacteria, whereas research in these areas in archaea is only beginning. All organisms have evolved a variety of strategies for coping with high-temperature stress, and among these strategies is the increased synthesis of HSPs. The facts that both high temperatures and chemical stresses induce the HSPs and that some of the HSPs recognize and bind to unfolded proteins in vitro have led to the theory that the function of HSPs is to prevent protein aggregation in vivo. The facts that some HSPs are abundant under normal growth conditions and that they assist in protein folding in vitro have led to the theory that they assist protein folding in vivo; in this role, they are referred to as molecular chaperones. The limited research on acquired thermotolerance, HSPs, and molecular chaperones in archaea, particularly the hyperthermophilic archaea, suggests that these extremophiles provide a new perspective in these areas of research, both because they are members of a separate phylogenetic domain and because they have evolved to live under extreme conditions.

  3. Temperature dependence of heat sensitization and thermotolerance induction with ethanol

    Cytoxicity of 1 M ethanol was strongly temperature dependent; survival curves between 340 and 390C were similar to heat survival curves between 40 and 450 without ethanol. Ethanol was non-toxic at 220; at 34.50 and 35.50 ethanol survival curves were biphasic. The major effect of 1 M ethanol was an effective temperature shift of 6.4 Celsius degrees, although temperatures between 340 and 360 caused additional sensitization reminiscent of the stepdown heating phenomenon. Induction of thermotolerance with equitoxic ethanol exposures at 35.50 and 370 or with heat alone (10 min, 450) resulted in tolerance development with similar kinetics; in contrast, ethanol exposures at 220 did not induce any tolerance development with similar kinetics; in contrast, ethanol exposures at 220 did not induce any tolerance to hyperthermia. These data provide a rationale for conflicting reports in the literature regarding thermotolerance induction by ethanol and suggest that ethanol causes ''heat'' stress at temperatures that are generally considered to be physiological. This interpretation predicts that the use of ethanol and other organic solvents in high concentrations will cause effects at 370 that normally occur only at hyperthermic temperatures, including membrane perturbations and HSP synthesis, and that ''physiological'' temperatures must be precisely controlled under those conditions

  4. Possible role of localized protein denaturation in the mechanism of induction of thermotolerance by heat, sodium-arsenite and ethanol.

    Burgman, P W; Kampinga, H H; Konings, A W

    1993-01-01

    Heat, sodium-arsenite, and ethanol-induced thermotolerance are compared, especially with regard to the induced resistance of proteins of the particulate fraction (PF) against heat-induced denaturation. While all three agents induce thermotolerance as expressed as an enhanced survival after hyperthermic treatment, it is found that while heat and sodium-arsenite also induce resistance in the PF, this is not the case for ethanol. To explain these differences a hypothesis is postulated in which resistance is induced in those subcellular fractions/structures that are damaged by the agent used for the induction of thermotolerance. Furthermore, the effect of inhibition of protein synthesis by cycloheximide during the development of thermotolerance is investigated. It is found that while heat- and ethanol-induced thermotolerance (survival) are partly protein synthesis-independent, sodium-arsenite-induced thermotolerance (survival) is completely protein synthesis-dependent. Protein-synthesis-independent thermotolerance induced heat resistance in the proteins of the PF to the same extent as protein-synthesis-independent thermotolerance. To explain the differences in the ability of the agents to induce protein-synthesis-independent thermotolerance a hypothesis is postulated in which this ability depends on the mechanism by which this agent inhibits protein synthesis during the thermotolerance-inducing treatment. In this hypothesis the involvement of hsp in protein synthesis-independent thermotolerance is assumed. PMID:8381841

  5. Assessment of variability in acquired thermotolerance: potential option to study genotypic response and the relevance of stress genes.

    Senthil-Kumar, Muthappa; Kumar, Ganesh; Srikanthbabu, Venkatachalayya; Udayakumar, Makarla

    2007-02-01

    High-temperature stress affects all growth stages of crops and ultimately yields. This is further aggravated by other environmental stresses like intermittent drought and high light. Management options are few and hence developing intrinsically tolerant plants is essential to combat the situation. As thermotolerance is a multigenic trait, emphasis needs to be on relevant approaches to assess genetic variability in basal and acquired tolerance. This is in fact the major aspect in crop improvement programmes. The relevance of temperature induction (acclimation) response (TIR), a high throughput approach to identify thermotolerant individuals and its utility as potential screening method is described here. This is based on the concept that stress-responsive genes are expressed only during initial stages of stress (acclimation stress) and bring about requisite changes in cell metabolism for adaptation. The fact that acclimation response is ubiquitous has been demonstrated in different crop plants in our studies and by others. Significance of acclimation in acquired tolerance and thus in assessing genetic variability in thermotolerance is discussed. The limitations of present approaches to validate the relevance of specific stress genes either in transgenics or in mutants or knock downs have been analyzed and the need to characterize transformants under conditions that trigger acquired tolerance is also highlighted. This review also focuses on the potential of exploiting acclimation response approach to improve the thermotolerance of crop plants by suitable breeding strategies. PMID:17207553

  6. Heating as a rapid purification method for recovering correctly-folded thermotolerant VH and VHH domains

    Muyldermans Serge

    2007-01-01

    Full Text Available Abstract Background Recombinant antibodies from Camelidae (VHHs are potentially useful tools for both basic research and biotechnological applications because of their small size, robustness, easy handling and possibility to refold after chemio-physical denaturation. Their heat tolerance is a particularly interesting feature because it has been recently related to both high yields during recombinant expression and selective purification of folded protein. Results Purification of recombinant RE3 VHH by heat treatment yielded the same amount of antibody as purification by affinity chromatography and negligible differences were found in stability, secondary structure and functionality. Similar results were obtained using another class of thermotolerant proteins, the single domain VH scaffold, described by Jespers et al. 8. However, thermosensitive VHs could not withstand the heat treatment and co-precipitated with the bacterial proteins. In both cases, the thermotolerant proteins unfolded during the treatment but promptly refolded when moved back to a compatible temperature. Conclusion Heat treatment can simplify the purification protocol of thermotolerant proteins as well as remove any soluble aggregate. Since the re-folding capability after heat-induced denaturation was previously correlated to higher performance during recombinant expression, a unique heating step can be envisaged to screen constructs that can provide high yields of correctly-folded proteins.

  7. Heat induced protein denaturation in the particulate fraction of HeLa S3 cells: effect of thermotolerance.

    Burgman, P W; Konings, A W

    1992-10-01

    In this study we investigated the effect of heat on the proteins of the particulate fraction (PF) of HeLa S3 cells using electron spin resonance (ESR) and thermal gel analysis (TGA). ESR detects overall conformational changes in proteins, while TGA detects denaturation (aggregation due to formation of disulfide bonds) in specific proteins. For ESR measurements the -SH groups of the proteins were labelled with a maleimido bound spin label (4-maleimido-tempo). The sample was heated inside the ESR spectrometer at a rate of 1 degree C/min. ESR spectra were made every 2-3 degrees C between 20 degrees C and 70 degrees C. In the PF of untreated cells conformational changes in proteins were observed in three temperature stretches: between 38 and 44 degrees C (transition A, TA); between 47 and 53 degrees C (transition B, TB); and above 58 degrees C (transition C, TC). With TGA, using the same heating rate, we identified three proteins (55, 70, and 90 kD) which denatured during TB. No protein denaturation was observed during TA, while during TC denaturation of all remaining proteins in the PF occurred. When the ESR and TGA measurements were done with the PF of (heat-induced) thermotolerant cells, TA was unchanged while TB and TC started at higher temperatures. The temperature shift for the onset of these transitions correlated with the degree of thermotolerance that was induced in the cells. These results suggest that protection against heat-induced denaturation of proteins in the PF is involved in heat induced thermotolerance. PMID:1325981

  8. Variation in Heat-shock Proteins and Photosynthetic Thermotolerance among Natural Populations of Chenopodium album L. from Contrasting Thermal Environments: Implications for Plant Responses to Global Warming

    Deepak Barua; Scott A. Heckathorn; James S. Coleman

    2008-01-01

    Production of heat-shock proteins (Hsps) is a key adaptation to acute heat stress and will be Important in determining plant responses to climate change. Further, intraspecifc variation in Hsps, which will influence species-level response to global warming, has rarely been examined in naturally occurring plants. To understand intraspeciflc variation in plant Hsps and its relevance to global warming, we examined Hsp content and thermotolerance in five naturally occurring populations of Chenopodium album L. from contrasting thermal environments grown at low and high temperatures. As expected,Hsp accumulation varied between populations, but this was related more to habitat variability than to mean temperature.Unexpectedly, Hsp accumulation decreased with increasing variability of habitat temperatures. Hsp accumulation also decreased with increased experimental growth temperatures. Physiological thermotolerance was partitioned into basal and induced components. As with Hsps, induced thermotolerance decreased with increasing temperature variability. Thus,populations native to the more stressful habitats, or grown at higher temperatures, had lower Hsp levels and induced thermotolerance, suggesting a greater reliance on basal mechanisms for thermotolerance. These results suggest that future global climate change will differentially impact ecotypes within species, possibly by selecting for increased basal versus inducible thermotolerance.

  9. Thermal protein denaturation and protein aggregation in cells made thermotolerant by various chemicals: role of heat shock proteins.

    Kampinga, H H; Brunsting, J F; Stege, G J; Burgman, P W; Konings, A W

    1995-08-01

    Thermotolerance (TT) induced by sodium arsenite (A-TT: 100 microM, 1 h, 37 degrees C) was compared to heat-induced thermotolerance (H-TT: 15 min, 44 degrees C) using HeLa S3 cells. All four pretreatments led to comparable levels of thermotolerance and also induced resistance to arsenite-, ethanol-, and diamide-induced toxicity (clonogenic ability). Stress-induced expression of the major heat shock proteins (hsp27, hsc70(p73), hsp70(p72), and hsp90) was generally highest in H-TT cells and lowest in A-TT cells. Interestingly, the four types of TT cells showed distinct differences in certain aspects of resistance against thermal protein damage. Thermal protein denaturation and aggregation determined in isolated cellular membrane fractions was found to be attenuated when they were isolated from H-TT and A-TT cells but not when isolated from E-TT and D-TT cells. The heat resistance in the proteins of the membrane fraction corresponded with elevated levels of hsp70(p72) associated with the isolated membrane fractions. In the nuclear fraction, only marginal (not significant) attenuation of the formation of protein aggregates (as determined by TX-100 (in)solubility) was observed. However, the postheat recovery from heat-induced protein aggregation in the nucleus was faster in H-TT, E-TT, and D-TT cells, but not in A-TT cells. Despite the fact that elevated levels of hsp27, hsp70(p73), and hsp70(p72) were found in the TX-100 insoluble nuclear fraction derived from all TT cells, no correlation was found with the degree of resistance in terms of the accelerated recovery from nuclear protein aggregation. The only correlation between accelerated recovery from nuclear protein aggregates was that with total cellular levels of hsp27. The data indicate that heat-induced loss of clonogenic ability may be a multitarget rather than a single target event. A threshold of damage may exist in cells after exposure to heat; multiple sets of proteins in (different compartments of) the cell

  10. QTL for the thermotolerance effect of heat hardening, knowckdown resistance to heat and chill-coma recovery in an intercontinental set of recombinant inbred lines of Drosophila melanogaster

    Norry, Fabian M.; Scannapieco, Alejandra C.; Sambucetti, Pablo;

    2008-01-01

    The thermotolerance effect of heat hardening (also called short-term acclimation), knockdown resistance to high temperature (KRHT) with and without heat hardening and chill-coma recovery (CCR) are important phenotypes of thermal adaptation in insects and other organisms. Drosophila melanogaster f...

  11. GENOTYPIC THERMOTOLERANCE IS ASSOCIATED WITH ELEVATED PRE-STRESS ANTIOXIDANT ENZYME ACTIVITY IN COTTON LEAVES AND PISTILS

    Numerous studies have illustrated the need for antioxidant enzymes in acquired photosynthetic thermotolerance, but information on their possible role in promoting innate thermotolerance in either leaves or reproductive tissues is limited for cotton. We investigated the hypothesis that genotypic diff...

  12. A KH Domain-Containing Putative RNA-Binding Protein Is Critical for Heat Stress-Responsive Gene Regulation and Thermotolerance in Arabidopsis

    Qingmei Guan; Changlong Wen; Haitao Zeng; Jianhua Zhu

    2013-01-01

    Heat stress is a severe environmental factor that significantly reduces plant growth and delays development.Heat stress factors (HSFs) are a class of transcription factors that are synthesized rapidly in response to elevations in temperature and are responsible for the transcription of many heat stress-responsive genes including those encoding heat shock proteins (HSPs).There are 21 HSFs in Arabidopsis,and recent studies have established that the HSFA1 family members are master regulators for the remaining HSFs.However,very little is known about upstream molecular factors that control the expression of HSFA1 genes and other HSF genes under heat stress.Through a forward genetic analysis,we identified RCF3,a K homology (KH) domain-containing nuclear-localized putative RNA-binding protein.RCF3 is a negative regulator of most HSFs,including HSFAla,HSFAlb,and HSFAld.In contrast,RCF3 positively controls the expression of HSFAle,HSFA3,HSFA9,HSFB3,and DREB2C.Consistently with the overall increased accumulation of heat-responsive genes,the rcf3 mutant plants are more tolerant than the wild-type to heat stress.Together,our results suggest that a KH domain-containing putative RNA-binding protein RCF3 is an important upstream regulator for heat stress-responsive gene expression and thermotolerance in Arabidopsis.

  13. Multiple heat priming enhances thermo-tolerance to a later high temperature stress via improving subcellular antioxidant activities in wheat seedlings

    Wang, Xiao; Cai, Jian; Liu, Fulai;

    2014-01-01

    Seedlings of winter wheat (Triticum aestivum L.) were firstly twice heat-primed at 32/24 °C, and subsequently subjected to a more severe high temperature stress at 35/27 °C. The later high temperature stress significantly decreased plant biomass and leaf total soluble sugars concentration. Howeve....... Collectively, heat priming effectively improved thermo-tolerance of wheat seedlings subjected to a later high temperature stress, which could be largely ascribed to the enhanced anti-oxidation at the subcellular level.......Seedlings of winter wheat (Triticum aestivum L.) were firstly twice heat-primed at 32/24 °C, and subsequently subjected to a more severe high temperature stress at 35/27 °C. The later high temperature stress significantly decreased plant biomass and leaf total soluble sugars concentration. However......, plants experienced priming (PH) up-regulated the Rubisco activase B encoding gene RcaB, which was in accordance with the higher photosynthesis rate in relation to the non-primed plants (NH) under the later high temperature stress. In relation to NH, the major chlorophyll a/b-binding protein gene Cab was...

  14. Two phases of response to long-term moderate heat: Variation in thermotolerance between Arabidopsis thaliana and its relative Arabis paniculata.

    Tang, Ting; Liu, Peile; Zheng, Guowei; Li, Weiqi

    2016-02-01

    Long-term moderate heat is often experienced by plants and will become even more common in the future due to global warming. However, the responses of plants to this stress have not been characterised. In the present study, growth between Arabidopsis thaliana and its relative Arabis paniculata upon long-term exposure to moderate heat was compared. It was found that the latter was more tolerant than the former, and the patterns of physiological and biochemical responses of both plants presented two phases. The early phase involved no significant visible morphological and physiological changes. It occurred during the first third of the heat treatment and was extended when the stress was attenuated. During the later phase, the plants died or were damaged. Heat shock proteins were dramatically induced at the early phase and gradually decreased at the later phase in A. thaliana. By contrast, the levels were induced and maintained in A. paniculata. Profiling of membrane lipids found that the two plants exhibited opposite patterns of lipid remodelling at the early phase: A. paniculata synthesised phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol and showed a rapid decrease in the degree of lipid unsaturation, while A. thaliana degraded its lipids at the early phase and showed an accelerated degradation at the later phase. These biochemical adjustments during the early phase could favor the thermotolerance of A. paniculata. These results suggest that this species could thus be a model for the study of resistance to long-term moderate heat, through a strategy by which plants can adapt to long-term moderate heat. PMID:26782026

  15. Analysis of the expression of putative heat-stress related genes in relation to thermotolerance of cork oak.

    Correia, Barbara; Rodriguez, José Luis; Valledor, Luis; Almeida, Tânia; Santos, Conceição; Cañal, Maria Jesús; Pinto, Glória

    2014-03-15

    Cork oak (Quercus suber L.) is a research priority in the Mediterranean area and because of cork oaks' distribution these stands are experiencing daily stress. Based on projections of intensifying climate change and considering the key role of exploring the recovery abilities, cork oak seedlings were subjected to a cumulative temperature increase from 25°C to 55°C and subsequent recovery. CO2 assimilation rate, chlorophyll fluorescence, anthocyanins, proline and lipid peroxidation were used to evaluate plant performance, while the relative abundance of seven genes encoding for proteins of cork oak with a putative role in thermal/stress regulation (POX1, POX2, HSP10.4, HSP17a.22, CHS, MTL and RBC) was analyzed by qPCR (quantitative Polymerase Chain Reaction). A temperature change to 35°C showed abundance alterations in the tested genes; at 45°C, the molecular changes were associated with an antioxidant response, possibly modulated by anthocyanins. At 55°C, HSP17a.22, MTL and proline accumulation were evident. After recovery, physiological balance was restored, whereas POX1, HSP10.4 and MTL abundances were suggested to be involved in increased thermotolerance. The data presented here are expected to pinpoint some pathways changes occurring during such stress and further recovery in this particular Mediterranean species. PMID:24594391

  16. Downregulation of CSD2 by a heat-inducible miR398 is required for thermotolerance in Arabidopsis

    Lu, Xiaoyan; Guan, Qingmei; Zhu, Jianhua

    2013-01-01

    MicroRNAs (miRNAs) play important roles in plant growth and development and abiotic stress responses. We report here that heat stress rapidly induces miR398 and reduces transcript of its target gene CSD2. Transgenic plants overexpressing the miR398-resistant form of CSD2 are more sensitive to heat stress than transgenic plants overexpressing normal coding sequence of CSD2. Expression of heat stress transcription factors (HSFs) and heat shock proteins (HSPs) is reduced in the heat-sensitive tr...

  17. SCREENING OF RICE GENOTYPES FOR THERMOTOLERANCE BY TIR TECHNIQUE

    K. Renuka Devi

    2013-12-01

    Full Text Available Production of rice--the world's most important crop for ensuring food security and addressing poverty will be defeated as temperatures increase in rice-growing areas with continued climate change. Climate change needs us to look at various alternatives for more drought tolerant and tougher strains and to develop a technique to screen a large number of genotypes for high temperature tolerance. Adapting temperature induction response (TIR technique 100 rice genotypes were screened for thermotolerance. Significant variation for acquired thermotolerance was observed in 100 rice lines. From the 100 genotypes 30 were exhibits themotolerance to induced high temperature.

  18. Advances in mechanisms and modifications for rendering yeast thermotolerance.

    Gao, Liman; Liu, Yueqin; Sun, Hun; Li, Chun; Zhao, Zhiping; Liu, Guiyan

    2016-06-01

    Thermotolerant Saccharomyces cerevisiae is widely regarded as an attractive strain with which to accomplish the coupling of enzyme saccharification, ethanol fermentation and ethanol distillation in non-grain fuel bioethanol fermentation systems, and it has many advantages for increasing the ethanol yield and reducing production costs. This review provided an overview of the yeast heat-resistant mechanisms from six aspects, including gene expression responses, heat shock proteins, trehalose, ATPase, the ubiquitin-proteasome pathway and heat-induced antioxidant defenses. Innovative methods, such as random and rational strategies for improving yeast thermotolerance, were further discussed, and several special cases were provided. To rationally engineer thermotolerance in yeast, the advances in employing heat-resistant mechanisms of thermophiles were particularly discussed. By designing and constructing heat-resistant devices consists of heat-resistant parts from thermophiles to yeast, a superior thermotolerance of S. cerevisiae has been achieved, providing a new system with important applications for research regarding the improvement of the robustness of microbes. PMID:26685013

  19. Para-Aminobenzoic Acid (PABA) Synthase Enhances Thermotolerance of Mushroom Agaricus bisporus

    Zhonglei Lu; Xiangxiang Kong; Zhaoming Lu; Meixiang Xiao; Meiyuan Chen; Liang Zhu; Yuemao Shen; Xiangyang Hu; Siyang Song

    2014-01-01

    Most mushrooms are thermo-sensitive to temperatures over 23°C, which greatly restricts their agricultural cultivation. Understanding mushroom's innate heat-tolerance mechanisms may facilitate genetic improvements of their thermotolerance. Agaricus bisporus strain 02 is a relatively thermotolerant mushroom strain, while strain 8213 is quite thermo-sensitive. Here, we compared their responses at proteomic level to heat treatment at 33°C. We identified 73 proteins that are differentially express...

  20. The structural-functional organization of thermotolerant complexes of actinomycetes in desert and volcanic soils

    Zenova, G. M.; Kurapova, A. I.; Lysenko, A. M.; Zvyagintsev, D. G.

    2009-05-01

    It has been found that the number of thermotolerant actinomycetes in strongly heated soils of deserts and volcanic regions is comparable to or exceeds the number of mesophilic actinomycetes. Among the latter group, streptomyces usually predominate; among thermotolerant actinomycetes, representatives of the Micromonospora, Streptosporangium, Actinomadura, Saccharopolyspora, Microtetraspora, and Microbispora genera are identified. Thermotolerant actinomycetes display the full cycle of their development in these soils. The method of fluorescent in situ hybridization has made it possible to determine that mycelial forms predominate among the metabolically active representatives of Actinobacteria; their portion increases with the rise in the temperature of soil incubation.

  1. Thermotolerance-induced goblet cell activity confers protection in post-operative gut barrier dysfunction.

    Ali, Rohana

    2009-06-01

    There is evidence that some level of protection against the adverse sequelae of surgery is provided by induction of thermotolerance; this protective effect was explored by study of several indicators of bowel wall damage in animals exposed to surgical insults. It has been argued that the mechanism of the protective effect of thermotolerance involves heat shock proteins (HSPs). We hypothesized that the protective effect of thermotolerance may be due in part to changes in the bowel wall itself, and we investigated this hypothesis in an experimental rat model.

  2. Overexpression of receptor-like kinase ERECTA improves thermotolerance in rice and tomato.

    Shen, Hui; Zhong, Xiangbin; Zhao, Fangfang; Wang, Yanmei; Yan, Bingxiao; Li, Qun; Chen, Genyun; Mao, Bizeng; Wang, Jianjun; Li, Yangsheng; Xiao, Guoying; He, Yuke; Xiao, Han; Li, Jianming; He, Zuhua

    2015-09-01

    The detrimental effects of global warming on crop productivity threaten to reduce the world's food supply. Although plant responses to changes in temperature have been studied, genetic modification of crops to improve thermotolerance has had little success to date. Here we demonstrate that overexpression of the Arabidopsis thaliana receptor-like kinase ERECTA (ER) in Arabidopsis, rice and tomato confers thermotolerance independent of water loss and that Arabidopsis er mutants are hypersensitive to heat. A loss-of-function mutation of a rice ER homolog and reduced expression of a tomato ER allele decreased thermotolerance of both species. Transgenic tomato and rice lines overexpressing Arabidopsis ER showed improved heat tolerance in the greenhouse and in field tests at multiple locations in China during several seasons. Moreover, ER-overexpressing transgenic Arabidopsis, tomato and rice plants had increased biomass. Our findings could contribute to engineering or breeding thermotolerant crops with no growth penalty. PMID:26280413

  3. The heat shock factor family from Triticum aestivum in response to heat and other major abiotic stresses and their role in regulation of heat shock protein genes

    Xue, Gang-ping; Sadat, Shahab; Drenth, Janneke; McIntyre, C. Lynne

    2013-01-01

    Heat shock factors (Hsfs) play a central regulatory role in acquired thermotolerance. To understand the role of the major molecular players in wheat adaptation to heat stress, the Hsf family was investigated in Triticum aestivum. Bioinformatic and phylogenetic analyses identified 56 TaHsf members, which are classified into A, B, and C classes. Many TaHsfs were constitutively expressed. Subclass A6 members were predominantly expressed in the endosperm under non-stress conditions. Upon heat str...

  4. Thermotolerance and protein glycosylation: Inhibition studies with sodium fluoride, azauridine and tunicamycin

    The glycosylation hypothesis predicts increased incorporation of monosaccharides into 0-linked glycoproteins during thermotolerance development and inhibition of thermotolerance when this process is blocked. Specific inhibitors of 0-linked glycosylation are not available. The authors examined the effect of non-specific inhibition of glycosylation on thermotolerance development by: 1. restriction of both exogenous sugars and endogeneous sugar synthesis with NaF to block glycolysis while providing L-glutamine as a substrate for ATP synthesis in the TCA cycle; or 2. inhibition of UDP-sugar synthesis using azauridine and tunicamycin. Inhibitors were added to cell cultures after heat conditioning (10 min, 450) and removed after 6 hr prior to 450-test heating. Sugar deprivation was achieved with 10mM NaF in glucose-free EBSS, supplemented with 2mM L-glutamine. Synthesis of UDP-sugars was inhibited with 1mM azauridine + 1μg/ml tunicamycin. Thermotolerance development was inhibited 87% by NaF/glutamine and 47% by azauridine/tunicamycin. For example, the D/sub o/ of the thermotolerant cells was 42.5 min (control D/sub o/ = 3 min), but only 5.5 min with inhibition by the NaF solution. These results support the absolute requirement of sugar precursors for thermotolerance development as predicted by the glycosylation hypothesis

  5. Rickettsia influences thermotolerance in the whitefly Bemisia tabaci B biotype

    Marina Brumin; Svetlana Kontsedalov; Murad Ghanim

    2011-01-01

    The whitefly Bemisia tabaci harbors Portiera aleyrodidarum,an obligatory symbiotic bacterium,as well as several secondary symbionts,including Rickettsia,Hamiltonella,Wolbachia,Arsenophonus,Cardinium and Fritschea,the function of which is unknown.In Israel,Rickettsia is found in both the B and Q of B.tabaci biotypes,and while all other secondary symbionts are located in the bacteriomes,Rickettsia can occupy most of the body cavity of the insect.We tested whether Rickettsia influences the biology of B.tabaci and found that exposing a Rickettsia-containing population to increasing temperatures significantly increases its tolerance to heat shock that reached 40℃,compared to a Rickettsia-free population.This increase in tolerance to heat shock was not associated with specific induction of heat-shock protein gene expression; however,it was associated with eduction in Rickettsia numbers as was assessed by quantitative real-time polymerase chain reaction and fluorescence in situ hybridization analyses.To assess the causes for thermotolerance when ickettsia is reduced,we tested whether its presence is associated with the induction of genes required for thermotolerance.We found that under normal 25℃ rearing temperature,genes associated with response to stress such as cytoskeleton genes are induced in the Rickettsia-containing population.Thus,the presence of Rickettsia in B.tabaci under normal conditions induces the expression of genes required for thermotolerance that under high temperatures indirectly lead to this tolerance.

  6. Radiosensitivity and thermosensitization of thermotolerant Chinese hamster cells and RIF-1 tumors

    CHO cells subline HA-1 were made thermotolerant by a priming heat treatment(430C, 30 min). Later, 4, 16, or 24 hr, they were either irradiated or heated (430C, 30 min) and irradiated. Thermotolerance had no effect on the radiation sensitivity of the cells as measured by the D0 value of the clonogenic survival curve. However the N value of the curve (width of shoulder) showed a significant increase at 24 hr, indicating an increased capacity to accumulate sublethal damage. The same priming treatment was given to RIF-1 tumors growing in C3H mice. Later, 24 hr, when the tumors were either irradiated or heated (430C, 30 min) and irradiated, it was found that thermotolerance had no effect on the radiosensitivity of the cells as measured by in vitro assay. However, thermal radiosensitization was not apparent 24 hr after the priming treatment

  7. Salvaging effect of triacontanol on plant growth, thermotolerance, macro-nutrient content, amino acid concentration and modulation of defense hormonal levels under heat stress.

    Waqas, Muhammad; Shahzad, Raheem; Khan, Abdul Latif; Asaf, Sajjad; Kim, Yoon-Ha; Kang, Sang-Mo; Bilal, Saqib; Hamayun, Muhammad; Lee, In-Jung

    2016-02-01

    In this study, it was hypothesized that application of triacontanol, a ubiquitous saturated primary alcohol, at different times-before (TBHS), mid (TMHS), and after (TAHS) heat stress-will extend heat stress (HS) protection in mungbean. The effect of triacontanol on the levels of defense hormones abscisic acid (ABA) and jasmonic acid (JA) was investigated along with the plant growth promotion, nutrient and amino acid content with and without heat stress. Heat stress caused a prominent reduction in plant growth attributes, nutrient and amino acid content, which were attributed to the decreased level of ABA and JA. However, application of triacontanol, particularly in the TBHS and TMHS treatments, reversed the deleterious effects of HS by showing increased ABA and JA levels that favored the significant increase in plant growth attributes, enhanced nutrient content, and high amount of amino acid. TAHS, a short-term application of triacontanol, also significantly increased ABA and JA levels and thus revealed important information of its association with hormonal modulation. The growth-promoting effect of triacontanol was also confirmed under normal growth conditions. To the best of our knowledge, this study is the first to demonstrate the beneficial effects of triacontanol, with or without heat stress, on mungbean and its interaction with or regulation of the levels of defense hormones. PMID:26744997

  8. The Metabolic Basis of Pollen Thermo-Tolerance: Perspectives for Breeding

    Marine J. Paupière

    2014-09-01

    Full Text Available Crop production is highly sensitive to elevated temperatures. A rise of a few degrees above the optimum growing temperature can lead to a dramatic yield loss. A predicted increase of 1–3 degrees in the twenty first century urges breeders to develop thermo-tolerant crops which are tolerant to high temperatures. Breeding for thermo-tolerance is a challenge due to the low heritability of this trait. A better understanding of heat stress tolerance and the development of reliable methods to phenotype thermo-tolerance are key factors for a successful breeding approach. Plant reproduction is the most temperature-sensitive process in the plant life cycle. More precisely, pollen quality is strongly affected by heat stress conditions. High temperature leads to a decrease of pollen viability which is directly correlated with a loss of fruit production. The reduction in pollen viability is associated with changes in the level and composition of several (groups of metabolites, which play an important role in pollen development, for example by contributing to pollen nutrition or by providing protection to environmental stresses. This review aims to underline the importance of maintaining metabolite homeostasis during pollen development, in order to produce mature and fertile pollen under high temperature. The review will give an overview of the current state of the art on the role of various pollen metabolites in pollen homeostasis and thermo-tolerance. Their possible use as metabolic markers to assist breeding programs for plant thermo-tolerance will be discussed.

  9. Impact of heat shock on heat shock proteins expression,biological and commercial traits of Bombyx mori

    VASUDHA B. CHAVADI; APARNA H. S OSALEGOWDA; MANJUNATHA H.B OREGOWDA

    2006-01-01

    We report the thermotolerance of new bivoltine silkworm, Bombyx mori strains NB4D2, KSO1, NP2, CSR2 and CSR4 and differential expression of heat shock proteins at different instars. Different instars of silkworm larva were subjected to heat shock at 35℃,40℃ and 45℃ for 2 hours followed by 2 hours recovery. Heat shock proteins were analyzed by SDS-PAGE. The impact of heat shock on commercial traits of cocoons was analyzed by following different strategies in terms of acquired thermotolerance over control. Comparatively NP2 exhibited better survivability than other strains. Resistance to heat shock was increased as larval development proceeds in the order of first instar > second instar > third instar > fourth instar > fifth instar in all silkworm strains. Expression of heat shock proteins varies in different instars. 90 kDa in the first, second and third instars, 84 kDa in the fourth instar and 84, 62, 60, 47 and 33 kDa heat shock proteins in fifth instar was observed in response to heat shock. Relative influence of heat shock on commercial traits that correspond to different stages was significant in all strains. In NB4D2, cocoon and shell weight significantly increased to 17.52% and 19.44% over control respectively. Heat shock proteins as molecular markers for evaluation and evolution of thermotolerant silkworm strains for tropics was discussed.

  10. Directed evolution of a filamentous fungus for thermotolerance

    Lyons Thomas J

    2009-08-01

    Full Text Available Abstract Background Filamentous fungi are the most widely used eukaryotic biocatalysts in industrial and chemical applications. Consequently, there is tremendous interest in methodology that can use the power of genetics to develop strains with improved performance. For example, Metarhizium anisopliae is a broad host range entomopathogenic fungus currently under intensive investigation as a biologically based alternative to chemical pesticides. However, it use is limited by the relatively low tolerance of this species to abiotic stresses such as heat, with most strains displaying little to no growth between 35–37°C. In this study, we used a newly developed automated continuous culture method called the Evolugator™, which takes advantage of a natural selection-adaptation strategy, to select for thermotolerant variants of M. anisopliae strain 2575 displaying robust growth at 37°C. Results Over a 4 month time course, 22 cycles of growth and dilution were used to select 2 thermotolerant variants of M. anisopliae. Both variants displayed robust growth at 36.5°C, whereas only one was able to grow at 37°C. Insect bioassays using Melanoplus sanguinipes (grasshoppers were also performed to determine if thermotolerant variants of M. anisopliae retained entomopathogenicity. Assays confirmed that thermotolerant variants were, indeed, entomopathogenic, albeit with complex alterations in virulence parameters such as lethal dose responses (LD50 and median survival times (ST50. Conclusion We report the experimental evolution of a filamentous fungus via the novel application of a powerful new continuous culture device. This is the first example of using continuous culture to select for complex phenotypes such as thermotolerance. Temperature adapted variants of the insect-pathogenic, filamentous fungus M. anisopliae were isolated and demonstrated to show vigorous growth at a temperature that is inhibitory for the parent strain. Insect virulence assays

  11. Para-aminobenzoic acid (PABA synthase enhances thermotolerance of mushroom Agaricus bisporus.

    Zhonglei Lu

    Full Text Available Most mushrooms are thermo-sensitive to temperatures over 23°C, which greatly restricts their agricultural cultivation. Understanding mushroom's innate heat-tolerance mechanisms may facilitate genetic improvements of their thermotolerance. Agaricus bisporus strain 02 is a relatively thermotolerant mushroom strain, while strain 8213 is quite thermo-sensitive. Here, we compared their responses at proteomic level to heat treatment at 33°C. We identified 73 proteins that are differentially expressed between 02 and 8213 or induced upon heat stress in strain 02 itself, 48 of which with a known identity. Among them, 4 proteins are constitutively more highly expressed in 02 than 8213; and they can be further upregulated in response to heat stress in 02, but not in 8213. One protein is encoded by the para-aminobenzoic acid (PABA synthase gene Pabs, which has been shown to scavenge the reactive oxygen species in vitro. Pabs mRNA and its chemical product PABA show similar heat stress induction pattern as PABA synthase protein and are more abundant in 02, indicating transcriptional level upregulation of Pabs upon heat stress. A specific inhibitor of PABA synthesis impaired thermotolerance of 02, while exogenous PABA or transgenic overexpression of 02 derived PABA synthase enhanced thermotolerance of 8213. Furthermore, compared to 8213, 02 accumulated less H2O2 but more defense-related proteins (e.g., HSPs and Chitinase under heat stress. Together, these results demonstrate a role of PABA in enhancing mushroom thermotolerance by removing H2O2 and elevating defense-related proteins.

  12. Experimental Space Shuttle Orbiter Studies to Acquire Data for Code and Flight Heating Model Validation

    Wadhams, T. P.; Holden, M. S.; MacLean, M. G.; Campbell, Charles

    2010-01-01

    In an experimental study to obtain detailed heating data over the Space Shuttle Orbiter, CUBRC has completed an extensive matrix of experiments using three distinct models and two unique hypervelocity wind tunnel facilities. This detailed data will be employed to assess heating augmentation due to boundary layer transition on the Orbiter wing leading edge and wind side acreage with comparisons to computational methods and flight data obtained during the Orbiter Entry Boundary Layer Flight Experiment and HYTHIRM during STS-119 reentry. These comparisons will facilitate critical updates to be made to the engineering tools employed to make assessments about natural and tripped boundary layer transition during Orbiter reentry. To achieve the goals of this study data was obtained over a range of Mach numbers from 10 to 18, with flight scaled Reynolds numbers and model attitudes representing key points on the Orbiter reentry trajectory. The first of these studies were performed as an integral part of Return to Flight activities following the accident that occurred during the reentry of the Space Shuttle Columbia (STS-107) in February of 2003. This accident was caused by debris, which originated from the foam covering the external tank bipod fitting ramps, striking and damaging critical wing leading edge heating tiles that reside in the Orbiter bow shock/wing interaction region. During investigation of the accident aeroheating team members discovered that only a limited amount of experimental wing leading edge data existed in this critical peak heating area and a need arose to acquire a detailed dataset of heating in this region. This new dataset was acquired in three phases consisting of a risk mitigation phase employing a 1.8% scale Orbiter model with special temperature sensitive paint covering the wing leading edge, a 0.9% scale Orbiter model with high resolution thin-film instrumentation in the span direction, and the primary 1.8% scale Orbiter model with detailed

  13. Quantification of the Effects of Salt Stress and Physiological State on Thermotolerance of Bacillus cereus ATCC 10987 and ATCC 14579

    Besten, den H.M.W.; Mataragas, M.; Moezelaar, R.; Abee, T.; Zwietering, M.H.

    2006-01-01

    The food-borne pathogen Bacillus cereus can acquire enhanced thermal resistance through multiple mechanisms. Two Bacillus cereus strains, ATCC 10987 and ATCC 14579, were used to quantify the effects of salt stress and physiological state on thermotolerance. Cultures were exposed to increasing concen

  14. Reconstruction of thermotolerant yeast by one-point mutation identified through whole-genome analyses of adaptively-evolved strains.

    Satomura, Atsushi; Miura, Natsuko; Kuroda, Kouichi; Ueda, Mitsuyoshi

    2016-01-01

    Saccharomyces cerevisiae is used as a host strain in bioproduction, because of its rapid growth, ease of genetic manipulation, and high reducing capacity. However, the heat produced during the fermentation processes inhibits the biological activities and growth of the yeast cells. We performed whole-genome sequencing of 19 intermediate strains previously obtained during adaptation experiments under heat stress; 49 mutations were found in the adaptation steps. Phylogenetic tree revealed at least five events in which these strains had acquired mutations in the CDC25 gene. Reconstructed CDC25 point mutants based on a parental strain had acquired thermotolerance without any growth defects. These mutations led to the downregulation of the cAMP-dependent protein kinase (PKA) signaling pathway, which controls a variety of processes such as cell-cycle progression and stress tolerance. The one-point mutations in CDC25 were involved in the global transcriptional regulation through the cAMP/PKA pathway. Additionally, the mutations enabled efficient ethanol fermentation at 39 °C, suggesting that the one-point mutations in CDC25 may contribute to bioproduction. PMID:26984760

  15. Pleurotus sajor-caju HSP100 complements a thermotolerance defect in hsp104 mutant Saccharomyces cerevisiae

    Jin-Ohk Lee; Mi-Jeong Jeong; Tack-Ryun Kwon; Seung-Kon Lee; Myung-Ok Byun; Ill-Min Chung; Soo-Chul Park

    2006-09-01

    A putative Hsp100 gene was cloned from the fungus Pleurotus sajor-caju. mRNA expression studies demonstrated that this gene (designated PsHsp100) is highly induced by high temperature, induced less strongly by exposure to ethanol, and not induced by drought or salinity. Heat shock induction is detectable at 37°C and reaches a maximum level at 42°C. PsHsp100 mRNAlevels sharply increased within 15 min of exposure to high temperature, and reached a maximum expression level at 2 h that was maintained for several hours. These results indicate that PsHsp100 could work at an early step in thermotolerance. To examine its function, PsHsp100 was transformed into a temperature-sensitive hsp104 deletion mutant Saccharomyces cerevisiae strain to test the hypothesis that PsHSP100 is an protein that functions in thermotolerance. Overexpression of PsHSP100 complemented the thermotolerance defect of the hsp104 mutant yeast, allowing them survive even at 50°C for 4 h. These results indicate that PsHSP100 protein is functional as an HSP100 in yeast and could play an important role in thermotolerance in P. sajor-caju.

  16. Pleurotus sajor-caju HSP100 complements a thermotolerance defect in hsp104 mutant Saccharomyces cerevisiae

    Jin-Ohk Lee; Mi-Jeong Jeong; Tack-Ryun Kwon; Seung-Kon Lee; Myung-Ok Byun; Ill-Min Chung; Soo-Chul Park

    2006-06-01

    A putative Hsp100 gene was cloned from the fungus Pleurotus sajor-caju. mRNA expression studies demonstrated that this gene (designated PsHsp100) is highly induced by high temperature, induced less strongly by exposure to ethanol, and not induced by drought or salinity. Heat shock induction is detectable at 37°C and reaches a maximum level at 42°C. PsHsp100 mRNAlevels sharply increased within 15 min of exposure to high temperature, and reached a maximum expression level at 2 h that was maintained for several hours. These results indicate that PsHsp100 could work at an early step in thermotolerance. To examine its function, PsHsp100 was transformed into a temperature-sensitive hsp104 deletion mutant Saccharomyces cerevisiae strain to test the hypothesis that PsHSP100 is an protein that functions in thermotolerance. Overexpression of PsHSP100 complemented the thermotolerance defect of the hsp104 mutant yeast, allowing them survive even at 50°C for 4 h. These results indicate that PsHSP100 protein is functional as an HSP100 in yeast and could play an important role in thermotolerance in P. sajor-caju.

  17. Effects of hyperthermia on the linear and quadratic parameters of the radiation survival curve of mammalian cells: influence of thermotolerance

    The authors conclude that their results show that thermotolerance modifies the effects of heat, both its direct cytotoxicity and radiosensitization in the same way. At an equal level of cell lethality for non-tolerant and thermotolerant cells, thermal enchancement of radiation effects is the same, both with regard to TER (Dsub(o)) (Haveman et al. 1987), TER (β) and presumably TER (α). With regard to clinical implications, when hyperthermia is to be combined with interstitial low dose-rate irradiation, a substantial enhancement of the effectiveness of irradiation may be expected. (author)

  18. Calcium pretreatment increases thermotolerance of Laminaria japonica sporophytes

    You Wang; Qingyun Yu; Xuexi Tang; Lili Wang

    2009-01-01

    Calcium is a secondary messenger in plant signaling,and its concentration changes spatially and temporally during the course of heat stress.In the present study,potassium antimonate was used to visualize calcium localization in blades of a marine macroalga,the juvenile Laminariajaponica sporophytes under heat stress (25 ℃).Result showed that loosely bound calcium was mainly distributed on the cell wall under normal conditions (10 ℃),and flowed into the cytoplasm when exposed to heat.The simutaneous assay on the antioxidant system changes was performed.Oxidative damage,as measured by generation of reactive oxygen species (ROS) malondialdehyde (MDA) content,increased significantly during heat stress,and calcium pretreatment alleviated oxidative damage.The assay on the activities of six antioxidant enzymes demonstrated that their enzymatic activities were inhibited when exposed to heat stress,but Ca2+ pretreatment effectively attenuated the inhibition.Results in the present study inferred that calcium homeostasis plays an essential role in L.japonica sporophyte when exposed to heat,and calcium pretreatment could improve its thermo-tolerance.

  19. Thermotolerant yeasts and application for ethanol production

    To-on, N.; Charernjiratrakul, W.; Dissara, Y.

    2007-01-01

    A total of 70 thermotolerant yeast strains were isolated at 40oC from 145 samples including fruit, leaves, flowers, soils and oil-palm fruits. Six isolates showed maximum growth at 40oC within 18 h. Three isolates (MIY1, MIY48 and MIY57) were selected based on their ability to ferment glucose and sucrose rapidly (24 h) and showed the maximum temperature for growth at 42oC but it was good at 40oC. MIY57 produced 4.6% (v/v) ethanol at 40oC from a medium containing 15% glucose. The optimum culti...

  20. Saclay Reactor: acquired knowledge by two years experience in heat transfer using compressed gas

    Describes the conception and functioning of a new reactor (EL-2) using compressed gas as primary coolant. The aim of the use of compressed gas as primary coolant is to reduce the quantity of heavy water used in the functioning of the reactor. Description of the reactor vessel (dimensions, materials, reflector and protection). Description of the cells and the circulation of the gas within the cells. A complete explanation of the control and regulating of the reaction by the ionization chamber is given. Heavy water is used as modulator: it describes the heavy water system and its recombination system. The fuel slugs are cooled by compressed gas: its system is described as well as the blower and the heat exchanger system. Water is supplied by a cooling tower which means the reactor power is dependant of the atmospheric conditions. Particular attention has been given to the tightness of the different systems used. The relation between neutron flow and the thermal output is discussed: the thermal output can be calculated by measuring the gas flow and its heating or by measuring the neutron flow within the reactor, both methods gives closed results. Reactivity study: determination of the different factors which induce a variation of reactivity. Heat transfer: discussion on the use of different heat transfer systems, determination of the required chemical and physical properties of the primary coolant as well as the discussion of the nuclear and thermal requirements for the choice of it. A comparison between the use of nitrogen and carbon dioxide gas shows an advantage in using nitrogen with the existing knowledge. Reflexion on the relevance of this work and the future perspectives of the use of compressed gas as primary coolant. (M.P.)

  1. Induced thermotolerance and stress resistance in larvae of the freshwater prawn, Macrobrachium rosenbergii (de Man, 1879)

    Rahman, M.M.; Wille, M.; Cavalli, R.O.; Sorgeloos, P; Clegg, J. S.

    2005-01-01

    Optimal conditions for heat shock (HS) were used to demonstrate induced thermotolerance (ITT) in larvae of the prawn, Macrobrachium rosenbergii. Larvae from three different broodstock nutritional regimes exhibited comparable degrees of ITT, which remained high for about 4 days. Survival and growth of larvae given the standard HS treatment (37 °C for 30 min) were not statistically different from those of controls, so the cost of mounting a heat shock response was not sufficient to reduce those...

  2. Trampling impacts on thermotolerant vegetation of geothermal areas in New Zealand.

    Burns, Bruce R; Ward, Jonet; Downs, Theresa M

    2013-12-01

    Geothermal features such as geysers, mud pools, sinter terraces, fumaroles, hot springs, and steaming ground are natural attractions often visited by tourists. Visitation rates for such areas in the Taupo Volcanic Zone of New Zealand are in the order of hundreds of thousands annually. These areas are also habitat for rare and specialized plant and microbial communities that live in the steam-heated soils of unusual chemical composition. We evaluated historical and current trampling impacts of tourists on the thermotolerant vegetation of the Waimangu and Waiotapu geothermal areas near Rotorua, and compared the results to experimental trampling at a third site (Taheke) not used by tourists. Historical tourism has removed vegetation and soil from around key features, and remaining subsoil is compacted into an impervious pavement on which vegetation recolonization is unlikely in the short term. Social tracks made by tourists were present at both tourist sites often leading them onto hotter soils than constructed tracks. Vegetation height and cover were lower on and adjacent to social tracks than further from them. Thermotolerant vegetation showed extremely low resistance to experimental trampling. This confirms and extends previous research that also shows that thallophytes and woody shrubs, life forms that dominate in thermotolerant vegetation, are vulnerable to trampling damage. Preservation of these vulnerable ecosystems must ensure that tourist traffic is confined to existing tracks or boardwalks, and active restoration of impacted sites may be warranted. PMID:24136681

  3. Trampling Impacts on Thermotolerant Vegetation of Geothermal Areas in New Zealand

    Burns, Bruce R.; Ward, Jonet; Downs, Theresa M.

    2013-12-01

    Geothermal features such as geysers, mud pools, sinter terraces, fumaroles, hot springs, and steaming ground are natural attractions often visited by tourists. Visitation rates for such areas in the Taupo Volcanic Zone of New Zealand are in the order of hundreds of thousands annually. These areas are also habitat for rare and specialized plant and microbial communities that live in the steam-heated soils of unusual chemical composition. We evaluated historical and current trampling impacts of tourists on the thermotolerant vegetation of the Waimangu and Waiotapu geothermal areas near Rotorua, and compared the results to experimental trampling at a third site (Taheke) not used by tourists. Historical tourism has removed vegetation and soil from around key features, and remaining subsoil is compacted into an impervious pavement on which vegetation recolonization is unlikely in the short term. Social tracks made by tourists were present at both tourist sites often leading them onto hotter soils than constructed tracks. Vegetation height and cover were lower on and adjacent to social tracks than further from them. Thermotolerant vegetation showed extremely low resistance to experimental trampling. This confirms and extends previous research that also shows that thallophytes and woody shrubs, life forms that dominate in thermotolerant vegetation, are vulnerable to trampling damage. Preservation of these vulnerable ecosystems must ensure that tourist traffic is confined to existing tracks or boardwalks, and active restoration of impacted sites may be warranted.

  4. Genetically altering the expression of neutral trehalase gene affects conidiospore thermotolerance of the entomopathogenic fungus Metarhizium acridum

    Peng Guoxiong

    2011-02-01

    Full Text Available Abstract Background The entomopathogenic fungus Metarhizium acridum has been used as an important biocontrol agent instead of insecticides for controlling crop pests throughout the world. However, its virulence varies with environmental factors, especially temperature. Neutral trehalase (Ntl hydrolyzes trehalose, which plays a role in environmental stress response in many organisms, including M. acridum. Demonstration of a relationship between Ntl and thermotolerance or virulence may offer a new strategy for enhancing conidiospore thermotolerance of entomopathogenic fungi through genetic engineering. Results We selected four Ntl over-expression and four Ntl RNA interference (RNAi transformations in which Ntl expression is different. Compared to the wild-type, Ntl mRNA expression was reduced to 35-66% in the RNAi mutants and increased by 2.5-3.5-fold in the over-expression mutants. The RNAi conidiospores exhibited less trehalase activity, accumulated more trehalose, and were much more tolerant of heat stress than the wild-type. The opposite effects were found in conidiospores of over-expression mutants compared to RNAi mutants. Furthermore, virulence was not altered in the two types of mutants compared to the wild type. Conclusions Ntl controlled trehalose accumulation in M. acridum by degrading trehalose, and thus affected conidiospore thermotolerance. These results offer a new strategy for enhancing conidiospore thermotolerance of entomopathogenic fungi without affecting virulence.

  5. Blueberry polyphenols increase lifespan and thermotolerance in Caenorhabditis elegans.

    Wilson, Mark A; Shukitt-Hale, Barbara; Kalt, Wilhelmina; Ingram, Donald K; Joseph, James A; Wolkow, Catherine A

    2006-02-01

    The beneficial effects of polyphenol compounds in fruits and vegetables are mainly extrapolated from in vitro studies or short-term dietary supplementation studies. Due to cost and duration, relatively little is known about whether dietary polyphenols are beneficial in whole animals, particularly with respect to aging. To address this question, we examined the effects of blueberry polyphenols on lifespan and aging of the nematode, Caenorhabditis elegans, a useful organism for such a study. We report that a complex mixture of blueberry polyphenols increased lifespan and slowed aging-related declines in C. elegans. We also found that these benefits did not just reflect antioxidant activity in these compounds. For instance, blueberry treatment increased survival during acute heat stress, but was not protective against acute oxidative stress. The blueberry extract consists of three major fractions that all contain antioxidant activity. However, only one fraction, enriched in proanthocyanidin compounds, increased C. elegans lifespan and thermotolerance. To further determine how polyphenols prolonged C. elegans lifespan, we analyzed the genetic requirements for these effects. Prolonged lifespan from this treatment required the presence of a CaMKII pathway that mediates osmotic stress resistance, though not other pathways that affect stress resistance and longevity. In conclusion, polyphenolic compounds in blueberries had robust and reproducible benefits during aging that were separable from antioxidant effects. PMID:16441844

  6. Interactive Effects of Elevated CO2 and Ozone on Leaf Thermotolerance in Field-grown Glycine max

    Sasmita Mishra; Scott A. Heckathorn; Deepak Barua; Dan Wang; Puneet Joshi; E. William Hamilton Ⅲ; Jonathan Frantz

    2008-01-01

    Humans are increasing atmospheric CO2, ground-level ozone (O3), and mean and acute high temperatures. Laboratory studies show that elevated CO2 can increase thermotolerance of photosynthesis in C3 plants. O3-related oxidative stress may offset benefits of elevated CO2 during heat-waves. We determined effects of elevated CO2 and O3 on leaf thermotolerance of field-grown Glycine max (soybean, C3). Photosynthetic electron transport (φet) was measured in attached leaves heated in situ and detached leaves heated under ambient CO2 and O3. Heating decreased φet, which O3 exacerbated. Elevated CO2 prevented O3-related decreases during heating, but only increased φet under ambient O3 in the field. Heating decreased chlorophyll and carotenoids, especially under elevated CO2. Neither CO2 nor O3 affected heat-shock proteins. Heating increased catalase (except in high O3) and CulZn-superoxide dismutase (SOD), but not MnSOD; CO2 and O3 decreased catalase but neither SOD. Soluble carbohydrates were unaffected by heating, but increased in elevated CO2. Thus, protection of photosynthesis during heat stress by elevated CO2 occurs in field-grown soybean under ambient O3, as in the lab, and high CO2 limits heat damage under elevated O3, but this protection is likely from decreased photorespiration and stomatal conductance rather than production of heat-stress adaptations.

  7. Thermotolerant yeasts and application for ethanol production

    To-on, N.

    2007-07-01

    Full Text Available A total of 70 thermotolerant yeast strains were isolated at 40oC from 145 samples including fruit, leaves, flowers, soils and oil-palm fruits. Six isolates showed maximum growth at 40oC within 18 h. Three isolates (MIY1, MIY48 and MIY57 were selected based on their ability to ferment glucose and sucrose rapidly (24 h and showed the maximum temperature for growth at 42oC but it was good at 40oC. MIY57 produced 4.6% (v/v ethanol at 40oC from a medium containing 15% glucose. The optimum cultivation conditions for growth and ethanol production of MIY57 was 5% inoculum into the fermentation medium containing 15% glucose and 1% yeast extract with initial pH of 4.5 on a shaking incubator at 150 rpm at 40oC. MIY57, under these conditions, produced maximum ethanol of 5.0% (v/v after 48 h incubation while S. cerevisiae TISTR 5048 produced only 3.7% (v/v. Maximum cell dry weight was 7.2 g/L (at 18 h, again much higher than that of S. cerevisiae TISTR 5048 (4.1 g/L. Based on morphological, physiological and molecular studies, this strain (MIY57 was identified as Saccharomyces cerevisiae.

  8. Effects of salicylic acid on thermotolerance and cardenolide accumulation under high temperature stress in Digitalis trojana Ivanina.

    Cingoz, Gunce Sahin; Gurel, Ekrem

    2016-08-01

    Long periods of high temperature or transitory increased temperature, a widespread agricultural problem, may lead to a drastic reduction in economic yield, affecting plant growth and development in many areas of the world. Heat stress causes many anatomical and physiological changes in plants. Its unfavorable effects can be alleviated by thermotolerance induced by exogenous application of plant growth regulators and osmoprotectants or by gradual application of temperature stress. Digitalis trojana Ivanina is an important medicinal plant species well known mainly for its cardenolides. The production of cardenolides via traditional agriculture is commercially inadequate. In this study, elicitation strategies were employed for improving crop thermotolerance and accumulation of cardenolides. For these purposes, the effects of salicylic acid (SA) and/or high temperature treatments in inducing cardenolide accumulation and thermotolerance were tested in callus cultures of D. trojana. Considerable increases in the production of cardenolides (up to 472.28 μg.g(-1) dry weight, dw) and induction of thermotolerance capacity were observed when callus cultures were exposed to high temperature for 2 h after pretreating with SA. High temperature treatments (2 h and 4 h) caused a marked reduction in superoxide dismutase (SOD; EC 1.15.1.1) and catalase (CAT; EC 1.11.1.6) activities, while SA pretreatment increased their activities. High temperature and/or SA appeared to increase the levels of proline, total phenolic, and flavonoid content. Elevated phenolic accumulation could be associated with increased stress protection. These results indicated that SA treatments induced synthesis of antioxidants and cardenolides, which may play a significant role in resistance to high temperature stress. PMID:27105421

  9. Physiological responses in a variable environment: relationships between metabolism, hsp and thermotolerance in an intertidal-subtidal species.

    Yun-wei Dong

    Full Text Available Physiological responses to temperature reflect the evolutionary adaptations of organisms to their thermal environment and the capability of animals to tolerate thermal stress. Contrary to conventional metabolism theory, increasing environmental temperatures have been shown to reduce metabolic rate in rocky-eulittoral-fringe species inhabiting highly variable environments, possibly as a strategy for energy conservation. To study the physiological adaptations of an intertidal-subtidal species to the extreme and unpredictable heat stress of the intertidal zone, oxygen consumption rate and heat shock protein expression were quantified in the sea cucumber Apostichopus japonicus. Using simulate natural temperatures, the relationship between temperature, physiological performance (oxygen consumption and heat shock proteins and thermotolerance were assessed. Depression of oxygen consumption rate and upregulation of heat shock protein genes (hsps occurred in sequence when ambient temperature was increased from 24 to 30°C. Large-scale mortality of the sea cucumber occurred when temperatures rose beyond 30°C, suggesting that the upregulation of heat shock proteins and mortality are closely related to the depression of aerobic metabolism, a phenomenon that is in line with the concept of oxygen- and capacity-limited thermal tolerance (OCLTT. The physiologically-related thermotolerance of this sea cucumber should be an adaptation to its local environment.

  10. Expression and thermotolerance of calreticulin during pollen development in tobacco

    Hrubá, Petra; Honys, David; Tupý, Jaroslav

    2005-01-01

    Roč. 18, č. 3 (2005), s. 143-148. ISSN 0934-0882 R&D Projects: GA ČR GP522/02/D075; GA MŠk LZ1K03018; GA AV ČR KJB6038409 Institutional research plan: CEZ:AV0Z50380511 Keywords : tobacco * pollen development * thermotolerance Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.278, year: 2005

  11. THERMOTOLERANT NON-FECAL SOURCE 'KLEBSIELLA PNEUMONIAE': VALIDITY OF THE FECAL COLIFORM TEST IN RECREATIONAL WATERS

    Wisconsin pulp and paper mill processing plants were evaluated for fecal coliform and total Klebsiella (i.e., thermotolerant and thermointolerant) bacterial concentrations. Using the standard fecal coliform test, up to 90 per cent of non-fecal source thermo-tolerant K. pneumoniae...

  12. Genome-wide analysis of the CaHsp20 gene family in pepper: comprehensive sequence and expression profile analysis under heat stress.

    Guo, Meng; Liu, Jin-Hong; Lu, Jin-Ping; Zhai, Yu-Fei; Wang, Hu; Gong, Zhen-Hui; Wang, Shu-Bin; Lu, Ming-Hui

    2015-01-01

    The Hsp20 genes are present in all plant species and play important roles in alleviating heat stress and enhancing plant thermotolerance by preventing the irreversible aggregation of denaturing proteins. However, very little is known about the CaHsp20 gene family in pepper (Capsicum annuum L.), an important vegetable crop with character of temperate but thermosensitive. In this study, a total of 35 putative pepper Hsp20 genes (CaHsp20s) were identified and renamed on the basis of their molecular weight, and then their gene structure, genome location, gene duplication, phylogenetic relationship, and interaction network were also analyzed. The expression patterns of CaHsp20 genes in four different tissues (root, stem, leaf, and flower) from the thermotolerant line R9 under heat stress condition were measured using semi-quantitative RT-PCR. The transcripts of most CaHsp20 genes maintained a low level in all of the four tissues under normal temperature condition, but were highly induced by heat stress, while the expression of CaHsp16.6b, 16.7, and 23.8 were only detected in specific tissues and were not so sensitive to heat stress like other CaHsp20 genes. In addition, compared to those in thermotolerant line R9, the expression peak of most CaHsp20 genes in thermosensitive line B6 under heat stress was hysteretic, and several CaHsp20 genes (CaHsp16.4, 18.2a, 18.7, 21.2, 22.0, 25.8, and 25.9) showed higher expression levels in both line B6 and R9. These data suggest that the CaHsp20 genes may be involved in heat stress and defense responses in pepper, which provides the basis for further functional analyses of CaHsp20s in the formation of pepper acquired thermotoleance. PMID:26483820

  13. Survey of thermotolerant Campylobacter in pheasant (Phasianus colchicus

    Alessandro Fioretti

    2010-01-01

    Full Text Available This study was conducted with the aim to evaluate the prevalence of thermotolerant Campylobacter spp. in pheasant (Phasianus colchicus in Southern Italy. To achieve this goal, 60 cloacal swabs were collected. Campylobacter spp. were isolated from 52 out of 60 cloacal swabs tested. As proved by PCR, 100% of the strains were identified as C. coli (52/52, and 10 out of the 52 (19.2% positive samples were also positive to C. jejuni. The pheasant, can be considered, at least theoretically, as potential Campylobacter carriers.

  14. Thioredoxin Reductase Type C (NTRC) Orchestrates Enhanced Thermotolerance to Arabidopsis by Its Redox-Dependent Holdase Chaperone Function

    Ho Byoung Chae; Jeong Chan Moon; Mi Rim Shin; Yong Hun Chi; Young Jun Jung; Sun Yong Lee; Ganesh M.Nawkar

    2013-01-01

    Genevestigator analysis has indicated heat shock induction of transcripts for NADPH-thioredoxin reductase,type C (NTRC) in the light.Here we show overexpression of NTRC in Arabidopsis (NTRCoE) resulting in enhanced tolerance to heat shock,whereas NTRC knockout mutant plants (ntrcl) exhibit a temperature sensitive phenotype.To investigate the underlying mechanism of this phenotype,we analyzed the protein's biochemical properties and protein structure.NTRC assembles into homopolymeric structures of varying complexity with functions as a disulfide reductase,a foldase chaperone,and as a holdase chaperone.The multiple functions of NTRC are closely correlated with protein structure.Complexes of higher molecular weight (HMW) showed stronger activity as a holdase chaperone,while low molecular weight (LMW) species exhibited weaker holdase chaperone activity but stronger disulfide reductase and foldase chaperone activities.Heat shock converted LMW proteins into HMW complexes.Mutations of the two active site Cys residues of NTRC into Ser (C217/454S-NTRC) led to a complete inactivation of its disulfide reductase and foldase chaperone functions,but conferred only a slight decrease in its holdase chaperone function.The overexpression of the mutated C217/454S-NTRC provided Arabidopsis with a similar degree of thermotolerance compared with that of NTRCoE plants.However,after prolonged incubation under heat shock,NTRCoE plants tolerated the stress to a higher degree than C217/454S-NTRCoE plants.The results suggest that the heat shock-mediated holdase chaperone function of NTRC is responsible for the increased thermotolerance of Arabidopsis and the activity is significantly supported by NADPH.

  15. Decolorization of Distillery Effluent by Thermotolerant Bacillus subtilis

    Soni Tiwari

    2012-01-01

    Full Text Available Problem statement: Ethanol production from sugarcane molasses generate large volume of effluent containing high Biological Oxygen Demand (BOD and Chemical Oxygen Demand (COD along with melanoidin, a color compound generally produced by Millard reaction. Melanodin is a recalcitrant compound degraded by specific microorganisms having ability to produce mono and di-oxygenases peroxidases, phenoxidases and laccases, are mainly responsible for degradation of complex aromatic hydrocarbons like color compound. These compounds causes several toxic effects on living system, therefore may be treated before disposal. Approach: The purpose of this study was to isolate a potential thermotolerant melanoidin decolorizing bacterium from natural resources for treatment of distillery effluent at industrial level. Results: Total 10 isolates were screened on solid medium containing molasses pigments. Three potential melanoidin decolorizing thermotolerant bacterial isolates identified as Bacillus subtilis, Bacillus cereus and Pseudomonas sp. were further optimized for decolorization at different physico-chemical and nutritional level. Out of these three, Bacillus subtilis showed maximum decolorization (85% at 45°C using (w/v 0.1%, glucose; 0.1%, peptone; 0.05%, MgSO4; 0.01%, KH2PO4; pH-6.0 within 24h of incubation under static condition. Conclusion/Recommendations: The strain of Bacillus subtilis can tolerate higher temperature and required very less carbon (0.1%, w/v and nitrogen sources (0.1%, w/v in submerged fermentation. It can be utilized for melanoidin decolorization of distillery effluent at industrial scale.

  16. Acquired Techniques

    Lunde Nielsen, Espen; Halse, Karianne

    2013-01-01

    Acquired Techniques - a Leap into the Archive, at Aarhus School of Architecture. In collaboration with Karianne Halse, James Martin and Mika K. Friis. Following the footsteps of past travelers this is a journey into tools and techniques of the architectural process. The workshop will focus upon...

  17. Acquired blepharoptosis

    Oosterhuis, HJGH

    1996-01-01

    A review is given of the aetiology and possible treatment of acquired (non-congenital) blepharoptosis, which is a common but not specific sign of neurological disease: The diagnostic categories of upper eyelid drooping are scheduled as (a) pseudo-ptosis due to a local process or overactivity of eye

  18. Global Gene-Expression Analysis to Identify Differentially Expressed Genes Critical for the Heat Stress Response in Brassica rapa.

    Xiangshu Dong

    Full Text Available Genome-wide dissection of the heat stress response (HSR is necessary to overcome problems in crop production caused by global warming. To identify HSR genes, we profiled gene expression in two Chinese cabbage inbred lines with different thermotolerances, Chiifu and Kenshin. Many genes exhibited >2-fold changes in expression upon exposure to 0.5- 4 h at 45°C (high temperature, HT: 5.2% (2,142 genes in Chiifu and 3.7% (1,535 genes in Kenshin. The most enriched GO (Gene Ontology items included 'response to heat', 'response to reactive oxygen species (ROS', 'response to temperature stimulus', 'response to abiotic stimulus', and 'MAPKKK cascade'. In both lines, the genes most highly induced by HT encoded small heat shock proteins (Hsps and heat shock factor (Hsf-like proteins such as HsfB2A (Bra029292, whereas high-molecular weight Hsps were constitutively expressed. Other upstream HSR components were also up-regulated: ROS-scavenging genes like glutathione peroxidase 2 (BrGPX2, Bra022853, protein kinases, and phosphatases. Among heat stress (HS marker genes in Arabidopsis, only exportin 1A (XPO1A (Bra008580, Bra006382 can be applied to B. rapa for basal thermotolerance (BT and short-term acquired thermotolerance (SAT gene. CYP707A3 (Bra025083, Bra021965, which is involved in the dehydration response in Arabidopsis, was associated with membrane leakage in both lines following HS. Although many transcription factors (TF genes, including DREB2A (Bra005852, were involved in HS tolerance in both lines, Bra024224 (MYB41 and Bra021735 (a bZIP/AIR1 [Anthocyanin-Impaired-Response-1] were specific to Kenshin. Several candidate TFs involved in thermotolerance were confirmed as HSR genes by real-time PCR, and these assignments were further supported by promoter analysis. Although some of our findings are similar to those obtained using other plant species, clear differences in Brassica rapa reveal a distinct HSR in this species. Our data could also provide a

  19. Identification of Mexican thermophilic and thermotolerant fungal isolates

    J. Córdova

    2003-01-01

    Full Text Available Forty-four fungal strains capable of growing at temperatures above 50 C were isolated from different samples of soil and coconut residues collected in Mexican tropical and subtropical regions. These thermophilic and thermotolerant fungal strains were identified by microscopical analysis using standard procedures. Three species were identified: Rhizomucor pusillus (LindtSchipper (19 strains, Rhizopus microsporus van Tieghem (6 strains, and Aspergillus fumigatus Fresenius (19 strains. Four strains identified as Rhizopus microsporus were ascribed to the variety rhizopodiformis; however, the other two strains showed new characteristics which require further analysis, such as a homothallic sexual reproduction. Aspergillus fumigatus was found in coconut residues as a common contaminant during the isolation of other thermophilic species. Strains were isolated from samples containing a high content of lipids (mainly from coconut coprah, and accordingly extracellular lipase biosynthesis was directly confirmed in Petri dishes for every strain.

  20. Human risk from thermotolerant Campylobacter on broiler meat in Denmark

    Boysen, Louise; Nauta, Maarten; Ribeiro Duarte, Ana Sofia;

    2013-01-01

    of intervention strategies based on monitoring data provided an added value, compared to the traditional approach of only using changes in prevalence. The estimated human health risk is a function of prevalence and the distribution of concentrations, and therefore takes best usage of the available data, while......This paper describes a new approach by which changes over time in the relative risk of human campylobacteriosis from broiler meat are evaluated through quantitative microbiological risk assessment modelling. Danish surveillance data collected at retail from 2001 to 2010 on numbers of thermotolerant...... Campylobacter spp. on Danish produced and imported chilled and frozen broiler meat were the basis for the investigation. The aim was to explore if the risk from the different meat categories had changed over time as a consequence of implemented intervention strategies. The results showed a slight decrease from...

  1. Food crops face rising temperatures: An overview of responses, adaptive mechanisms, and approaches to improve heat tolerance

    Neeru Kaushal

    2016-12-01

    Full Text Available The rising temperatures are resulting in heat stress for various agricultural crops to limit their growth, metabolism, and leading to significant loss of yield potential worldwide. Heat stress adversely affects normal plant growth and development depending on the sensitivity of each crop species. Each crop species has its own range of temperature maxima and minima at different developmental stages beyond which all these processes get inhibited. The reproductive stage is on the whole more sensitive to heat stress, resulting in impaired fertilization to cause abortion of flowers. During seed filling, heat stress retards seed growth by affecting all the biochemical events to reduce seed size. Unfavorable temperature may significantly affect photosynthesis, respiration, water balance, and membrane stability of leaves. To combat heat stress, plants acquire various defense mechanisms for their survival such as maintaining membrane stability, and scavenging reactive oxygen species by generating antioxidants and stress proteins. Thermo-tolerance can be improved by the accumulation of various compounds of low molecular mass known as thermo-protectants as well as phyto-hormones. Exogenous application of these molecules has benefited plants growing under heat stress. Alternatively, transgenic plants over-expressing the enzymes catalyzing the synthesis of these molecules may be raised to increase their endogenous levels to improve heat tolerance. In recent times, various transgenics have been developed with improved thermo-tolerance having potential benefits for inducing heat tolerance in food crops. Updated information about of the effects of heat stress on various food crops and their responses as well as adaptive mechanisms is reviewed here.

  2. A wheat lipid transfer protein 3 could enhance the basal thermotolerance and oxidative stress resistance of Arabidopsis.

    Wang, Fei; Zang, Xin-shan; Kabir, Muhammad Rezaul; Liu, Ke-lu; Liu, Zhen-shan; Ni, Zhong-fu; Yao, Ying-yin; Hu, Zhao-rong; Sun, Qi-xin; Peng, Hui-ru

    2014-10-15

    Wheat (Triticum aestivum L.) is one of the major grain crops, and heat stress adversely affects wheat production in many regions of the world. Previously, we found a heat-responsive gene named Lipid Transfer Protein 3 (TaLTP3) in wheat. TaLTP3 was deduced to be regulated by cold, ABA, MeJA, Auxin and oxidative stress according to cis-acting motifs in its promoter sequences. In this study, we show that TaLTP3 is responsive to prolonged water deficit, salt or ABA treatment in wheat seedlings. Also, TaLTP3 accumulation was observed after the plant suffered from heat stress both at the seedling and the grain-filling stages. TaLTP3 protein was localized in the cell membrane and cytoplasm of tobacco epidermal cells. Overexpression of TaLTP3 in yeast imparted tolerance to heat stress compared to cells expressing the vector alone. Most importantly, transgenic Arabidopsis plants engineered to overexpress TaLTP3 showed higher thermotolerance than control plants at the seedling stage. Further investigation indicated that transgenic lines decreased H₂O₂ accumulation and membrane injury under heat stress. Taken together, our results demonstrate that TaLTP3 confers heat stress tolerance possibly through reactive oxygen species (ROS) scavenging. PMID:25106859

  3. DNA polymerase activity in heat killing and hyperthermic radiosensitization of mammalian cells as observed after fractionated heat treatments.

    Jorritsma, J B; Burgman, P; Kampinga, H H; Konings, A W

    1986-03-01

    Possible relations between hyperthermic inactivation of alpha and beta DNA polymerase activity and hyperthermic cell killing or hyperthermic radiosensitization were investigated. Ehrlich Ascites Tumor (EAT) cells and HeLa S3 cells were treated with fractionated doses of hyperthermia. The heating schedules were chosen such that the initial heat treatment resulted in either thermotolerance or thermosensitization (step-down heating) for the second heat treatment. The results show that for DNA polymerase activity and heat radiosensitization (cell survival) no thermotolerance or thermosensitization is observed. Thus hyperthermic cell killing and DNA polymerase activity are not correlated. The correlation of hyperthermic radiosensitization and DNA polymerase activity was substantially less than observed in previous experiments with normotolerant and thermotolerant HeLa S3 cells. We conclude that alpha and beta DNA polymerase inactivation is not always the critical cellular process responsible for hyperthermic cell killing or hyperthermic radiosensitization. Other possible cellular systems that might determine these processes are discussed. PMID:3754338

  4. DNA polymerase activity in heat killing and hyperthermic radiosensitization of mammalian cells as observed after fractionated heat treatments

    Jorritsma, J.B.; Burgman, P.; Kampinga, H.H.; Konings, A.W.

    1986-03-01

    Possible relations between hyperthermic inactivation of alpha and beta DNA polymerase activity and hyperthermic cell killing or hyperthermic radiosensitization were investigated. Ehrlich Ascites Tumor (EAT) cells and HeLa S3 cells were treated with fractionated doses of hyperthermia. The heating schedules were chosen such that the initial heat treatment resulted in either thermotolerance or thermosensitization (step-down heating) for the second heat treatment. The results show that for DNA polymerase activity and heat radiosensitization (cell survival) no thermotolerance or thermosensitization is observed. Thus hyperthermic cell killing and DNA polymerase activity are not correlated. The correlation of hyperthermic radiosensitization and DNA polymerase activity was substantially less than observed in previous experiments with normotolerant and thermotolerant HeLa S3 cells. We conclude that alpha and beta DNA polymerase inactivation is not always the critical cellular process responsible for hyperthermic cell killing or hyperthermic radiosensitization. Other possible cellular systems that might determine these processes are discussed.

  5. Thermotolerant Yeasts for Bioethanol Production Using Lignocellulosic Substrates

    Pasha, Chand; Rao, L. Venkateswar

    glucose without a physical and chemical pre-treatment. The pre-treatment processes normally applied on the different substrates are acidic hydrolysis, steam explosion and wet oxidation. A problem for most pretreatment methods is the generation of compounds that are inhibitory towards the fermenting microorganisms, primarily phenols. Degradation products that could have inhibitory action in later fermentation steps are avoided during pre-treatment by wet oxidation. Followed by pre treatment, hydrolysed with enzymes known as cellulases and hemicellulases, which hydrolyse cellulose and hemicellulose respectively. The production of bioethanol requires two steps, fermentation and distillation. Practically all ethanol fermentation is still based on Saccharomyces cerevisiae . The fermentation using thermotolerant yeasts has more advantageous in that they have faster fermentation rates, avoid the cooling costs, and decrease the over all fermentation costs, so that ethanol can be made available at cheaper rates. In addition they can be used for efficient simultaneous saccharification and fermentation of cellulose by cellulases because the temperature optimum of cellulase enzymes (about 40 ° C to 45 ° C) is close to the fermentation temperature of thermotolerant yeasts. Hence selection and improvement of thermotolerant yeasts for bioconversion of lignocellulosic substrates is very useful.

  6. N-terminal arm of orchardgrass Hsp17.2 (DgHsp17.2) is essential for both in vitro chaperone activity and in vivo thermotolerance in yeast.

    Cha, Joon-Yung; Lee, Sang-Hoon; Seo, Kyung Hye; Choi, Young Jin; Cheong, Mi Sun; Son, Daeyoung

    2016-02-01

    Small heat shock proteins are well-known to function as chaperone in the protection of proteins and subcellular structures against stress-induced denaturation in many cell compartments. Irrespective of such general functional assignment, a proof of function in a living organism is missing. Here, we used heat-induced orchardgrass small Hsp17.2 (DgHsp17.2). Its function in in vitro chaperone properties has shown in protecting the model substrate, malate dehydrogenase (MDH) and citrate synthase (CS). Overexpression of DgHsp17.2 triggering strong chaperone activity enhanced in vivo thermotolerance of yeast cells. To identify the functional domain on DgHsp17.2 and correlationship between in vitro chaperone property and in vivo thermotolerance, we generated truncation mutants of DgHsp17.2 and showed essentiality of the N-terminal arm of DgHsp17.2 for the chaperone function. In addition, beyond for acquisition of thermotolerance irrespective of sequences are diverse among the small Hsps. However, any truncation mutants of DgHsp17.2 did not exhibit strong interaction with orchardgrass heat shock protein 70 (DgHsp70) different from mature DgHsp17.2, indicating that full-length DgHsp17.2 is necessary for cooperating with Hsp70 protein. Our study indicates that the N-terminal arm of DgHsp17.2 is an important region for chaperone activity and thermotolerance. PMID:26724757

  7. Evolution of thermotolerance in hot spring cyanobacteria of the genus Synechococcus

    Miller, S. R.; Castenholz, R. W.

    2000-01-01

    The extension of ecological tolerance limits may be an important mechanism by which microorganisms adapt to novel environments, but it may come at the evolutionary cost of reduced performance under ancestral conditions. We combined a comparative physiological approach with phylogenetic analyses to study the evolution of thermotolerance in hot spring cyanobacteria of the genus Synechococcus. Among the 20 laboratory clones of Synechococcus isolated from collections made along an Oregon hot spring thermal gradient, four different 16S rRNA gene sequences were identified. Phylogenies constructed by using the sequence data indicated that the clones were polyphyletic but that three of the four sequence groups formed a clade. Differences in thermotolerance were observed for clones with different 16S rRNA gene sequences, and comparison of these physiological differences within a phylogenetic framework provided evidence that more thermotolerant lineages of Synechococcus evolved from less thermotolerant ancestors. The extension of the thermal limit in these bacteria was correlated with a reduction in the breadth of the temperature range for growth, which provides evidence that enhanced thermotolerance has come at the evolutionary cost of increased thermal specialization. This study illustrates the utility of using phylogenetic comparative methods to investigate how evolutionary processes have shaped historical patterns of ecological diversification in microorganisms.

  8. Oxygen availability strongly affects chronological lifespan and thermotolerance in batch cultures of Saccharomyces cerevisiae

    Markus M.M. Bisschops

    2015-10-01

    Full Text Available Stationary-phase (SP batch cultures of Saccharomyces cerevisiae, in which growth has been arrested by carbon-source depletion, are widely applied to study chronological lifespan, quiescence and SP-associated robustness. Based on this type of experiments, typically performed under aerobic conditions, several roles of oxygen in aging have been proposed. However, SP in anaerobic yeast cultures has not been investigated in detail. Here, we use the unique capability of S. cerevisiae to grow in the complete absence of oxygen to directly compare SP in aerobic and anaerobic bioreactor cultures. This comparison revealed strong positive effects of oxygen availability on adenylate energy charge, longevity and thermotolerance during SP. A low thermotolerance of anaerobic batch cultures was already evident during the exponential growth phase and, in contrast to the situation in aerobic cultures, was not substantially increased during transition into SP. A combination of physiological and transcriptome analysis showed that the slow post-diauxic growth phase on ethanol, which precedes SP in aerobic, but not in anaerobic cultures, endowed cells with the time and resources needed for inducing longevity and thermotolerance. When combined with literature data on acquisition of longevity and thermotolerance in retentostat cultures, the present study indicates that the fast transition from glucose excess to SP in anaerobic cultures precludes acquisition of longevity and thermotolerance. Moreover, this study demonstrates the importance of a preceding, calorie-restricted conditioning phase in the acquisition of longevity and stress tolerance in SP yeast cultures, irrespective of oxygen availability.

  9. Production of fuel ethanol from molasses by thermotolerant yeast

    A thermotolerant strain of the yeast Kluyveromyces marxians, isolated from Kenana sugar factory in the Sudan, was used for the production of ethanol from molasses. Fermentations were carried out in a bioreactor with 10-litre working volume at three temperatures and three sugar concentrations in batch and at one temperature and three feeding rates in fed-batch processes. In the batch fermentations, the best results were obtained at 40 oC and 20% sugar, where a maximum of 9.2% (w/v) ethanol concentration was produced in 30 hours with a yield of 90% of the theoretical and a maximum ethanol specific productivity of 0.65 g per gramme yeast and hour. In the fed-batch process at 40 oC, the best results were obtained at 0.5 1/h feeding rate of a substrate with 400 g/1 sugar. Under such conditions, the yeast produced up to 9.34% (w/v) ethanol with 91.6% of the theoretical yield in 14 hours of fermentation and a maximum specific ethanol productivity of 0.9 g per gramme yeast and hour. (Author)

  10. Induction during G1 of heat radiosensitization in Chinese hamster ovary cells following single and fractionated heat doses

    When G1 Chinese hamster ovary cells were heated at 42.2 degrees C and X-irradiated, heat radiosensitization increased slightly with cell killing. However, when thermo-tolerance was allowed to develop by continuous heating for periods longer than 4 hours, which reduces survival to 0.18, heat radiosensitization no longer increased with continued heating or cell killing. When cells were heated with single doses at 45.5 degrees C, heat radiosensitization increased as a function of heat killing. However, if acute heat doses at 45.5 degrees C were fractionated and cells incubated for 10 hours at 37 degrees C between fractions, significant tolerance to heat radiosensitization was observed. For example, heating cells at 45.5 degrees C for 15 minutes reduced survival to 0.40 and decreased the D0 to 0.45 gray, whereas 2 fractionated 15-minute doses at 45.5 degrees C, separated by 10 hours at 37 degrees C, resulted in a D0 of 0.65 gray. Thus if heat killing increased without the development of thermotolerance, heat radiosensitization also increased continually, whereas when thermotolerance developed after continuous or fractionated heating without cell progression, some tolerance to continued heat radiosensitization also was observed. This tolerance to both heat killing and heat radiosensitization indicates that both involve similar target(s)

  11. Development of strains of the thermotolerant yeast Hansenula polymorpha capable of alcoholic fermentation of starch and xylan.

    Voronovsky, Andriy Y; Rohulya, Olha V; Abbas, Charles A; Sibirny, Andriy A

    2009-01-01

    The thermotolerant yeast Hansenula polymorpha ferments glucose and xylose to ethanol at high temperatures. However, H. polymorpha cannot utilize starchy materials or xylans. Heterologous amylolytic and xylanolytic enzymes have to be expressed in this yeast to provide for utilization and growth on starch and xylan. Genes SWA2 and GAM1 from the yeast Schwanniomyces occidentalis, encoding alpha-amylase and glucoamylase, respectively, were expressed in H. polymorpha. The expression was achieved by integration of the SWA2 and GAM1 genes under the strong constitutive promoter of the H. polymorpha glyceraldehyde-3-phosphate dehydrogenase gene (HpGAP) into H. polymorpha genome. Resulting transformants acquired the ability to grow on a minimal medium containing soluble starch as a sole carbon source. Ethanol production at high-temperature fermentation from starch by the recombinant strains was up to 10 g/L. The XYN2 gene encoding endoxylanase of the fungus Trichoderma reseei was expressed in H. polymorpha. Co-expression of xlnD gene coding for beta-xylosidase of the fungus Aspergillus niger and the XYN2 gene in H. polymorpha was achieved by integration of these genes under control of the HpGAP promoter. Resulting transformants were capable of growth and alcoholic fermentation on a minimal medium supplemented with birchwood xylan as a sole carbon source at 48 degrees C. PMID:19379821

  12. Laboratory Studies of Thermotolerance Acquisition during Seed Imbibition and Germination.

    Choinski, John S., Jr.

    1999-01-01

    Describes a series of low-cost experiments to investigate the ability of seeds from different species to acquire tolerance of thermal stress. Suggests links to discussions on molecular biology, physiology, ecology, and evolution. (WRM)

  13. Enhanced ethanol production from sugarcane juice by galactose adaptation of a newly isolated thermotolerant strain of Pichia kudriavzevii

    Dhaliwal, S.S.; Oberoi, H.S.; Sandhu, S.K.; Nanda, D.; Kumar, D.; Uppal, S.K.

    2011-01-01

    The thermotolerant yeast strain isolated from sugarcane juice through enrichment technique was identified as a strain of Pichiakudriavzevii (Issatchenkiaorientalis) through molecular characterization. The P. kudriavzevii cells adapted to galactose medium produced about 30% more ethanol from sugarcan

  14. [Small heat shock proteins and adaptation to hypertermia in various Drosophila species].

    Shilova, V Iu; Garbuz, D G; Evgen'ev, M B; Zatsepina, O G

    2006-01-01

    Expression level and kinetics of accumulation of small heat shock proteins (21-27 kDa group) have been investigated in three Drosophila species differing significantly by temperature niche and thermosensitivity. It was shown that low-latitude thermotolerant species D. virilis exceeds the high-latitude thermosensitive closely-related species D. lummei as well as distant thermosensitive species D. melanogaster in terms of small heat shock proteins expression and accumulation after temperature elevation. The data obtained enable to postulate an important role of small heat shock proteins in organism basal thermotolerance and general adaptation to adverse conditions of environment. PMID:16637267

  15. The effect of slaughter operations on the contamination of chicken carcasses with thermotolerant Campylobacter

    Rosenquist, Hanne; Sommer, Helle Mølgaard; Nielsen, Niels L.; Christensen, Bjarke Bak

    2006-01-01

    ) and had intestinal mean counts ranging from 6.65 to 8.20 log(10) cfu/g. A correlation between Campylobacter concentrations in intestinal content and on chicken carcasses after the defeathering operation was documented. This finding indicates that a reduction in the Campylobacter concentration on......To evaluate the effect of specific slaughter operations on the contamination of broiler carcasses with naturally occurring thermotolerant Campylobacter, experiments were carried out in two Danish commercial slaughter plants (Plant I and Plant 11). Six broiler flocks determined Campylobacter...... positive prior to slaughter were investigated at four sampling locations within each slaughter plant. Quantification of thermotolerant Campylobacter in 30 neck skin samples per flock per sampling location showed that the evisceration operation in Plant I led to a significant increase in the Campylobacter...

  16. Growth capacity of thermotolerant campylobacters in culture media supplemented with pig and cow blood

    Álvaro Tresierra-Ayala; Manuel Navas; Josué Flores; Ramsés Perea; Juan Huanaquiri; María Bendayán; Heriberto Fernández

    2010-01-01

    In this work 60 thermotolerant Campylobacter strains (37 C. jejuni and 23 C. coli) isolated from the cows, pigs, chickens and ducks (15 strains of each type of animal) were used to establish their growth capacity on media containing cow or swine blood as potential substitutes of sheep or horse blood. The growth capacity was assessed by viable counts on cow and swine blood media, using the modified Miles and Misra method. Campylobacter strains showed better growth in the media supplemented wit...

  17. Production of Bioethanol from Carrot Pomace Using the Thermotolerant Yeast Kluyveromyces marxianus

    Kow-Jen Duan; Bo-Hong Jiang; Chi-Yang Yu

    2013-01-01

    Carrot pomace, a major agricultural waste from the juice industry, was used as a feedstock for bioethanol production by fermentation with the thermotolerant yeast Kluyveromyces marxianus . Treatment of the carrot pomace with Accellerase TM 1000 and pectinase at 50 °C for 84 h, resulted in conversion of 42% of its mass to fermentable sugars, mainly glucose, fructose, and sucrose. Simultaneous saccharification and fermentation (SSF) at 42 °C was performed on 10% ( w / v ) carrot pomace; the c...

  18. Cloning, Expression, and Characterization of Thermotolerant Manganese Superoxide Dismutase from Bacillus sp. MHS47

    Supatra Areekit; Paisarn Khawsak; Arda Pakpitchareon; Kajeenart Potivejkul; Gaysorn Chansiri; Kosum Chansiri; Pornpimon Kanjanavas

    2011-01-01

    A superoxide dismutase gene from thermotolerant Bacillus sp. MHS47 (MnSOD47) was cloned, sequenced, and expressed. The gene has an open reading frame of 612 bp, corresponding to 203 deduced amino acids, with high homology to the amino acid sequences of B. thuringiensis (accession no. EEN01322), B. anthracis (accession no. NP_846724), B. cereus (accession no. ZP_04187911), B. weihenstephanensis (accession no. YP_001646918), and B. pseudomycoides. The conserved manganese-binding sites (H28, H83...

  19. Screening of thermotolerant and thermophilic fungi aiming β-xylosidase and arabinanase production

    Vivian Machado Benassi

    2014-12-01

    Full Text Available Plant cell wall is mainly composed by cellulose, hemicellulose and lignin. The heterogeneous structure and composition of the hemicellulose are key impediments to its depolymerization and subsequent use in fermentation processes. Thus, this study aimed to perform a screening of thermophilic and thermotolerant filamentous fungi collected from different regions of the São Paulo state, and analyze the production of β-xylosidase and arabinanase at different temperatures. These enzymes are important to cell wall degradation and synthesis of end products as xylose and arabinose, respectively, which are significant sugars to fermentation and ethanol production. A total of 12 fungal species were analyzed and 9 of them grew at 45 ºC, suggesting a thermophilic or thermotolerant character. Additionally Aspergillus thermomutatus anamorph of Neosartorya and A. parasiticus grew at 50 ºC. Aspergillus niger and Aspergillus thermomutatus were the filamentous fungi with the most expressive production of β-xylosidase and arabinanase, respectively. In general for most of the tested microorganisms, β-xylosidase and arabinanase activities from mycelial extract (intracellular form were higher in cultures grown at high temperatures (35-40 ºC, while the correspondent extracellular activities were favorably secreted from cultures at 30 ºC. This study contributes to catalogue isolated fungi of the state of São Paulo, and these findings could be promising sources for thermophilic and thermotolerant microorganisms, which are industrially important due to their enzymes.

  20. Hospital-acquired pneumonia

    ... this page: //medlineplus.gov/ency/article/000146.htm Hospital-acquired pneumonia To use the sharing features on this page, please enable JavaScript. Hospital-acquired pneumonia is an infection of the lungs ...

  1. 不同棉花种质资源耐热性鉴定%Identification for the Thermotolerance of Different Germplasm in Cotton

    刘少卿; 何守朴; 米拉吉古丽; 周忠丽; 孙君灵; 杜雄明

    2013-01-01

    随着全球气候变暖,高温胁迫已经成为影响棉花产量的主要因素之一.中国棉花种植区,在7月和8月棉花花铃高峰期经常出现周期性极端高温胁迫,导致蕾铃脱落,降低了产量,因此棉花耐热性种质的筛选迫在眉睫.本试验在新疆吐鲁番自然高温条件下,调查200份不同棉花种质资源的脱落率、花粉活力、叶片萎蔫程度、花粉形态、不孕子率等田间性状.然后选择29份不同耐热性种质在河南安阳种植,调查30、35、40、45和50℃离体培养条件下的花粉萌发率.不同耐热性种质资源在自然高温条件下的鉴定指标和室内离体培养花粉萌发率存在着极显著的差异.而且不同鉴定指标间也存在着不同的相关性.结合田间调查结果和花粉离体培养萌发率,将29份种质划分为耐高温型、较耐高温型、高温较敏感型和高温敏感型种质,并初步确定了耐热性的鉴定指标.%With global climate been wanning,heat stress has became a main factor influencing cotton product around the world. In cotton growing areas of China, especially in Yangtze River valley,unexpected periodic extreme high temperature usually occurred in the period of full florescence and boll setting, and this resulted in higher bud and boll abscission rates and lower lint yields. Hence, screening of heat resistant cotton germplasm is extremely urgent. In this study, we planted 200 different thermotolerance cotton germplasms in Tulufan of Xinjiang province located in west of china. We investigated the bud and boll abscission rates, pollen vitality, leaf wilting, pollen morphology, infertility seed rates and so on. And then 29 germplasms with different heat tolerance were growed in Anyang of Henan.The pollen germination rate in vitro at 30℃ ,35℃ ,40℃ ,45 ℃ ,and 50℃ were investigated respectively. There were significant differences in field index and pollen germination rate among different thermotolerance cotton

  2. Heterotypic Signals from Neural HSF-1 Separate Thermotolerance from Longevity.

    Douglas, Peter M; Baird, Nathan A; Simic, Milos S; Uhlein, Sarah; McCormick, Mark A; Wolff, Suzanne C; Kennedy, Brian K; Dillin, Andrew

    2015-08-18

    Integrating stress responses across tissues is essential for the survival of multicellular organisms. The metazoan nervous system can sense protein-misfolding stress arising in different subcellular compartments and initiate cytoprotective transcriptional responses in the periphery. Several subcellular compartments possess a homotypic signal whereby the respective compartment relies on a single signaling mechanism to convey information within the affected cell to the same stress-responsive pathway in peripheral tissues. In contrast, we find that the heat shock transcription factor, HSF-1, specifies its mode of transcellular protection via two distinct signaling pathways. Upon thermal stress, neural HSF-1 primes peripheral tissues through the thermosensory neural circuit to mount a heat shock response. Independent of this thermosensory circuit, neural HSF-1 activates the FOXO transcription factor, DAF-16, in the periphery and prolongs lifespan. Thus a single transcription factor can coordinate different stress response pathways to specify its mode of protection against changing environmental conditions. PMID:26257177

  3. Heterotypic Signals from Neural HSF-1 Separate Thermotolerance from Longevity

    Peter M. Douglas

    2015-08-01

    Full Text Available Integrating stress responses across tissues is essential for the survival of multicellular organisms. The metazoan nervous system can sense protein-misfolding stress arising in different subcellular compartments and initiate cytoprotective transcriptional responses in the periphery. Several subcellular compartments possess a homotypic signal whereby the respective compartment relies on a single signaling mechanism to convey information within the affected cell to the same stress-responsive pathway in peripheral tissues. In contrast, we find that the heat shock transcription factor, HSF-1, specifies its mode of transcellular protection via two distinct signaling pathways. Upon thermal stress, neural HSF-1 primes peripheral tissues through the thermosensory neural circuit to mount a heat shock response. Independent of this thermosensory circuit, neural HSF-1 activates the FOXO transcription factor, DAF-16, in the periphery and prolongs lifespan. Thus a single transcription factor can coordinate different stress response pathways to specify its mode of protection against changing environmental conditions.

  4. AtHsfA2 modulates expression of stress responsive genes and enhances tolerance to heat and oxidative stress in Arabidopsis

    LI Chunguang; CHEN Qijun; GAO Xinqi; QI Bishu; CHEN Naizhi; XU Shouming; CHEN Jia; WANG Xuechen

    2005-01-01

    There is increasing evidence for considerable interlinking between the responses to heat stress and oxidative stress, and recent researches suggest heat shock transcription factors (Hsfs) play an important role in linking heat shock with oxidative stress signals. In this paper, we present evidence that AtHsfA2 modulated expression of stress responsive genes and enhanced tolerance to heat and oxidative stress in Arabidopsis. Using Northern blot and quantitative RT-PCR analysis, we demonstrated that the expression of AtHsfA2 was induced by not only HS but also oxidative stress. By functional analysis of AtHsfA2 knockout mutants and AtHsfA2 overexpressing transgenic plants, we also demonstrated that the mutants displayed reduced the basal and acquired thermotolerance as well as oxidative stress tolerance but the overexpression lines displayed increased tolerance to these stress. The phenotypes correlated with the expression of some Hsps and APX1, ion leakage, H2O2 level and degree of oxidative injuries. These results showed that, by modulated expression of stress responsive genes, AtHsfA2 enhanced tolerance to heat and oxidative stress in Arabidopsis. So we suggest that AtHsfA2 plays an important role in linking heat shock with oxidative stress signals.

  5. Sea urchin development in a global change hotspot, potential for southerly migration of thermotolerant propagules

    Byrne, M.; Selvakumaraswamy, P.; Ho, M. A.; Woolsey, E.; Nguyen, H. D.

    2011-03-01

    The distribution of the sea urchin Heliocidaris erythrogramma coincides with the southeast Australia global change hot spot where marine ecosystems are warming significantly due to changes in ocean circulation. To address questions on future vulnerabilities, the thermotolerance of the planktonic life phase of H. erythrogramma was investigated in the climate and regionally relevant setting of projected near-future (2100) ocean warming. Experimental treatments ranged from 18 to 26 °C, with 26 °C representing +3-4 °C above recent ambient sea-surface temperatures. Developmental success across all stages (gastrula, 24 h; larva, 72 h; juvenile, 120 h) decreased with increasing temperature. Development was tolerant to a +1-2 °C increase above ambient, but significant deleterious effects were evident at +3-4 °C. However, larvae that developed through the early bottleneck of normal development at 26 °C metamorphosed successfully. The inverse relationship between temperature and planktonic larval duration (PLD) was seen in a 25% decrease in the PLD of H. erythrogramma at 24 and 26 oC. Ocean warming may be advantageous to a subset of larvae through early settlement and reduction of the vulnerable planktonic period. This positive effect of temperature may help buffer the negative effects of ocean warming. In parallel studies with progeny derived from northern (Coffs Harbour) and southern (Sydney) H. erythrogramma, northern embryos had significantly higher thermotolerance. This provides the possibility that H. erythrogramma populations might keep up with a warming world through poleward migration of thermotolerant propagules, facilitated by the strong southward flow of the East Australian Current. It is uncertain whether H. erythrogramma populations at the northern range of this species, with no source of immigrants, will have the capacity to persist in a warm ocean. Due to its extensive latitudinal distribution, its potential developmental thermotolerance and

  6. ISOLATION AND IDENTIFICATION OF A THERMOTOLERANT PLANT GROWTH PROMOTING PSEUDOMONAS PUTIDA PRODUCING TREHALOSE SYNTHASE

    Ali Sk.Z.; Sandhya Vardharajula

    2013-01-01

    A thermotolerant plant growth promoting Pseudomonas isolate growing at 40oC producing trehalose synthase (TreS) was isolated from rhizosphere soil under semi arid conditions of India. Trehalose synthase was extracted; purified and enzymatic activity was examined at various temperatures and pH. The optimum temperature and pH was 38oC and pH 7.5 and the activity declined at above or below the optimum pH and temperature. The enzyme was active on maltose and trehalose among saccharides tested. Th...

  7. Transcriptomic analysis of grape (Vitis vinifera L.) leaves during and after recovery from heat stress

    Liu Guo-Tian; Wang Jun-Fang; Cramer Grant; Dai Zhan-Wu; Duan Wei; Xu Hong-Guo; Wu Ben-Hong; Fan Pei-Ge; Wang Li-Jun; Li Shao-Hua

    2012-01-01

    Abstract Background Grapes are a major fruit crop around the world. Heat stress can significantly reduce grape yield and quality. Changes at the molecular level in response to heat stress and subsequent recovery are poorly understood. To elucidate the effect of heat stress and subsequent recovery on expression of genes by grape leaves representing the classic heat stress response and thermotolerance mechanisms, transcript abundance of grape (Vitis vinifera L.) leaves was quantified using the ...

  8. Production of Bioethanol from Carrot Pomace Using the Thermotolerant Yeast Kluyveromyces marxianus

    Chi-Yang Yu; Bo-Hong Jiang; Kow-Jen Duan [Tatung University, Tapei, Taiwan (China). Department of Bioengineering

    2013-03-15

    Carrot pomace, a major agricultural waste from the juice industry, was used as a feedstock for bioethanol production by fermentation with the thermotolerant yeast Kluyveromyces marxianus. Treatment of the carrot pomace with Accellerase(TM) 1000 and pectinase at 50 °C for 84 h, resulted in conversion of 42% of its mass to fermentable sugars, mainly glucose, fructose, and sucrose. Simultaneous saccharification and fermentation (SSF) at 42 °C was performed on 10% (w/v) carrot pomace; the concentration of ethanol reached 18 g/L and the yield of ethanol from carrot pomace was 0.18 g/g. The highest ethanol concentration of 37 g/L was observed with an additional charge of 10% supplemented to the original 10% of carrot pomace after 12 h; the corresponding yield was 0.185 g/g. Our results clearly demonstrated the potential of combining a SSF process with thermotolerant yeast for the production of bioethanol using carrot pomace as a feedstock.

  9. Validation of a PCR-based method for detection of food-borne thermotolerant Campylobacters in a multicenter collaborative trial

    Josefsen, Mathilde Hartmann; Cook, N.; D'Agostino, M.;

    2004-01-01

    A PCR-based method for rapid detection of food-borne thermotolerant campylobacters was evaluated through a collaborative trial with 12 laboratories testing spiked carcass rinse samples. The method showed an interlaboratory diagnostic sensitivity of 96.7% and a diagnostic specificity of 100% for...

  10. Laboratory-acquired brucellosis

    Fabiansen, C.; Knudsen, J.D.; Lebech, A.M.

    2008-01-01

    Brucellosis is a rare disease in Denmark. We describe one case of laboratory-acquired brucellosis from an index patient to a laboratory technician following exposure to an infected blood culture in a clinical microbiology laboratory Udgivelsesdato: 2008/6/9......Brucellosis is a rare disease in Denmark. We describe one case of laboratory-acquired brucellosis from an index patient to a laboratory technician following exposure to an infected blood culture in a clinical microbiology laboratory Udgivelsesdato: 2008/6/9...

  11. Effects of acid adaptation, product pH, and heating on survival of Escherichia coli O157:H7 in pepperoni.

    Riordan, D C; Duffy, G; Sheridan, J J; Whiting, R C; Blair, I S; McDowell, D A

    2000-04-01

    The thermotolerance of E. coli O157:H7 cells (strain 380-94) heated in pepperoni is reported. Information on the pattern of thermal inactivation of E. coli O157:H7 in pepperoni was applied in the development of heating processes designed to reduce E. coli O157:H7 numbers therein by 5 log(10) units. PMID:10742270

  12. Effects of Acid Adaptation, Product pH, and Heating on Survival of Escherichia coli O157:H7 in Pepperoni

    R. Riordan, Denise C.; Duffy, Geraldine; Sheridan, James J.; Whiting, Richard C.; Blair, Ian S.; McDowell, David A.

    2000-01-01

    The thermotolerance of E. coli O157:H7 cells (strain 380-94) heated in pepperoni is reported. Information on the pattern of thermal inactivation of E. coli O157:H7 in pepperoni was applied in the development of heating processes designed to reduce E. coli O157:H7 numbers therein by 5 log10 units.

  13. Yes-associated protein homolog, YAP-1, is involved in the thermotolerance and aging in the nematode Caenorhabditis elegans

    Iwasa, Hiroaki [Department of Medical Biochemistry, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo 113-8519 (Japan); Maimaiti, Sainawaer [Department of Medical Biochemistry, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo 113-8519 (Japan); Department of Psychotherapy, The Fourth People' s Hospital of Urumqi, Urumqi 830000 (China); Kuroyanagi, Hidehito [Laboratory of Gene Expression, Graduate School of Biomedical Science, Tokyo Medical and Dental University, Tokyo 113-8519 (Japan); Kawano, Shodai; Inami, Kazutoshi; Timalsina, Shikshya; Ikeda, Mitsunobu; Nakagawa, Kentaro [Department of Medical Biochemistry, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo 113-8519 (Japan); Hata, Yutaka, E-mail: yuhammch@tmd.ac.jp [Department of Medical Biochemistry, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo 113-8519 (Japan)

    2013-04-15

    The mammalian Hippo pathway comprises mammalian Ste20-like kinases (MST1/2) and large tumor suppressor kinases (LATS1/2). LATS1/2, which are activated by MST1/2, phosphorylate a transcriptional co-activator, yes-associated protein (YAP), and induce the recruitment of YAP by 14-3-3 to cytoplasm, so that the TEAD-dependent gene transcriptions are turned off. Although the core components of the Hippo pathway are well conserved in metazoans, it has been discussed that Caenorhabditis elegans lacks YAP ortholog, we found that F13E6.4 gene encodes a protein that shows sequence similarities to YAP in the N-terminal TEAD-binding domain and in the WW domain. We designated this gene as yap-1. YAP-1 is widely expressed in various cells such as epithelial cells, muscles, hypodermal cells, gonadal sheath cells, spermatheca, and hypodermal cells. YAP-1 is distributed in cytoplasm and nuclei. wts-1 (LATS ortholog) and ftt-2 (14-3-3 ortholog) knockdowns cause nuclear accumulation of YAP-1, supporting that the subcellular localization of YAP-1 is regulated in a similar way as that of YAP. Heat shock also causes the nuclear accumulation of YAP-1 but after heat shock, YAP-1 translocates to cytoplasm. Knockdowns of DAF-21 (HSP90 ortholog) and HSF-1block the nuclear export of YAP-1 during this recovery. YAP-1 overexpression is beneficial for thermotolerance, whereas YAP-1 hyperactivity induced by wts-1 and ftt-2 knockdowns is deleterious on thermal response and yap-1 deficiency promotes health aging. In short, YAP-1 partially shares basal characters with mammalian YAP and plays a role in thermal stress response and healthy aging. - Highlights: ► We named Caenorhabditis elegans F13E6.4 gene yap-1 as a putative YAP homolog. ► The localization of YAP-1 is regulated by WTS-1 and FTT-2. ► YAP-1 is involved in healthy aging and thermosensitivity.

  14. Yes-associated protein homolog, YAP-1, is involved in the thermotolerance and aging in the nematode Caenorhabditis elegans

    The mammalian Hippo pathway comprises mammalian Ste20-like kinases (MST1/2) and large tumor suppressor kinases (LATS1/2). LATS1/2, which are activated by MST1/2, phosphorylate a transcriptional co-activator, yes-associated protein (YAP), and induce the recruitment of YAP by 14-3-3 to cytoplasm, so that the TEAD-dependent gene transcriptions are turned off. Although the core components of the Hippo pathway are well conserved in metazoans, it has been discussed that Caenorhabditis elegans lacks YAP ortholog, we found that F13E6.4 gene encodes a protein that shows sequence similarities to YAP in the N-terminal TEAD-binding domain and in the WW domain. We designated this gene as yap-1. YAP-1 is widely expressed in various cells such as epithelial cells, muscles, hypodermal cells, gonadal sheath cells, spermatheca, and hypodermal cells. YAP-1 is distributed in cytoplasm and nuclei. wts-1 (LATS ortholog) and ftt-2 (14-3-3 ortholog) knockdowns cause nuclear accumulation of YAP-1, supporting that the subcellular localization of YAP-1 is regulated in a similar way as that of YAP. Heat shock also causes the nuclear accumulation of YAP-1 but after heat shock, YAP-1 translocates to cytoplasm. Knockdowns of DAF-21 (HSP90 ortholog) and HSF-1block the nuclear export of YAP-1 during this recovery. YAP-1 overexpression is beneficial for thermotolerance, whereas YAP-1 hyperactivity induced by wts-1 and ftt-2 knockdowns is deleterious on thermal response and yap-1 deficiency promotes health aging. In short, YAP-1 partially shares basal characters with mammalian YAP and plays a role in thermal stress response and healthy aging. - Highlights: ► We named Caenorhabditis elegans F13E6.4 gene yap-1 as a putative YAP homolog. ► The localization of YAP-1 is regulated by WTS-1 and FTT-2. ► YAP-1 is involved in healthy aging and thermosensitivity

  15. Understanding the mechanisms of ATPase beta family genes for cellular thermotolerance in crossbred bulls

    Deb, Rajib; Sajjanar, Basavaraj; Singh, Umesh; Alex, Rani; Raja, T. V.; Alyethodi, Rafeeque R.; Kumar, Sushil; Sengar, Gyanendra; Sharma, Sheetal; Singh, Rani; Prakash, B.

    2015-12-01

    Na+/K+-ATPase is an integral membrane protein composed of a large catalytic subunit (alpha), a smaller glycoprotein subunit (beta), and gamma subunit. The beta subunit is essential for ion recognition as well as maintenance of the membrane integrity. Present study was aimed to analyze the expression pattern of ATPase beta subunit genes (ATPase B1, ATPase B2, and ATPase B3) among the crossbred bulls under different ambient temperatures (20-44 °C). The present study was also aimed to look into the relationship of HSP70 with the ATPase beta family genes. Our results demonstrated that among beta family genes, transcript abundance of ATPase B1 and ATPase B2 is significantly ( P P mechanisms of ATPase beta family genes for cellular thermotolerance in cattle.

  16. Identification and characterization of diverse xylanases from thermophilic and thermotolerant fungi

    Bhat, M. K.

    2006-07-01

    Full Text Available Thirteen fungal isolates included in this study expressed multiple xylanase isoforms as observed by xylan zymograms of polyacrylamide gel electrophoresis (PAGE and isoelectrofocussing (IEF fractionated proteins. Eighty-three xylanases produced by these thermophilic and thermotolerant strains were detected using the IEF profiling technique. Xylanases identified on the basis of their isoelectric points (pI were functionally diverse and exhibited differential catalytic activities against various xylan types (birch wood xylan, larch wood xylan, oat spelt xylan, rye arabino xylan and wheat arabino xylan as well as debranched arabinan. Thermophilic isolates, Chaetomium thermophilum, Humicola insolens, Melanocarpus sp., Malbranchea sp. and Thermoascus aurantiacus, were found to produce alkaline active xylanases that showed a bleach boosting effect on Decker pulp resulting in increased brightness (1.60-2.04 ISO units.

  17. Screening and application of thermotolerant microorganisms and their flocculant for treatment of palm oil mill effluent

    Saithong Kaewchai

    2002-07-01

    Full Text Available Among fifteen thermotolerant polymer-producing isolates, three strains SM 29, WD 90, and SM 38 produced polymer posessing very high flocculating activities (24.81, 14.63 and 10.84, respectively and flocculation rates (94.29, 90.69 and 87.84, respectively. These three strains were identified to be Bacillus subtilis WD90, Bacillus subtilis SM 29, and Enterobacter agglomerans SM 38. Treatment of palm oil mill effluent (POME by these three selected strains under aerobic condition at 45ºC for 48 h revealed that neither oil separation nor flocculation of solids was observed. However, all three strains were able to decolorize the POME from dark brown to very light yellow. Flocculant produced from the three selected isolates could not separate the suspended solids and oil from the POME.

  18. Screening of thermotolerant microorganisms and application for oil separation from palm oil mill wastewater

    Aran H-Kittikun

    2007-05-01

    Full Text Available The characteristics of palm oil mill wastewater (POMW were brown color, pH 3.8-4.3, temperature 48-55oC, total solids 68.2-82.1 g/l, suspended solids 26.2-65.6 g/l, oil and grease 19.1-25.1 g/l, COD 49.9-160.7g/l and BOD 32.5-75.3 g/l. After centrifugation (3,184 xg of 50 ml POMW for 10 min, the POMW was separated into 3 layers: top (oil, middle (supernatant and bottom layer (sediment. The sediment containeddry weight 1.19 g and oil and grease 1.07 g. In order to release oil and grease trapped in palm fiber debris in the POMW, cellulase- and/or xylanase-enzyme-producing and thermotolerant microorganisms wereisolated. The isolates SO1 and SO2 were isolated from soil near the first anaerobic pond of the palm oil mill. They were aerobic, Gram positive, rod shaped, thermotolerant microorganisms and produced cellulase 12.11 U/ml (3 days and 7.2 U/ml (4 days, and xylanase 50.98 U/ml (4 days and 20.42 U/ml (4 days, respectivelyin synthetic medium containing carboxymethycellulose as a carbon source. When these 2 isolates were added into the steriled POMW under shaking condition for 7 days, after centrifugation at 3,184 xg the isolate SO1gave the better % reduction of dry weight (64.66 % and of oil and grease in the bottom layer (85.32 % of the POMW.

  19. Biopretreatment of palm oil mill effluent by thermotolerant polymer-producing fungi

    Masao Ukita

    2001-11-01

    Full Text Available Palm oil industry is one of the three major agro-industries in Southern Thailand and generates large quantities of effluent with high organic matter (BOD and COD values of 58,000 and 110,000 mg/l, respectively, total solids and suspended solids (70,000 and 40,000 mg/l, respectively, oil & grease (25,600 mg/l, and has a low pH (4.5. Conventional anaerobic ponding system is normally employed in palm oil mills to treat the effluent. To increase its efficiency, biopretreatment to remove the organic matter and oil & grease by thermotolerant polymer-producing fungi was investigated. The palm oil mill effluent (POME was treated by the two thermotolerant polymer-producing fungi, Rhizopus sp. ST4 and Rhizopus sp. ST29, at 45ºC under aseptic and septic conditions. Rhizopus sp. ST4 gave the same oil & grease removal (84.2% under both conditions but COD removal under septic condition (62.2% was 8.8% higher than that under aseptic condition (53.4%. On the contrary, Rhizopus sp. ST 29 under aseptic condition showed 11% and 25.4% higher oil & grease removal (91.4% and COD removal (66.0% than those under septic condition. Comparison between the two isolates under aseptic condition revealed that Rhizopus sp. ST29 exhibited higher oil & grease removal (91.4% as well as COD removal (66.0% than those of Rhizopus sp. ST4 (84.2% and 53.4%, respectively. Under septic condition, Rhizopus sp. ST4 gave higher oil & grease removal (84.2% and COD removal (62.2% than did Rhizopus sp. ST 29 (80.5 and 40.6%, respectively.

  20. Performance of a Heating Block System Designed for Studying the Heat Resistance of Bacteria in Foods.

    Kou, Xiao-Xi; Li, Rui; Hou, Li-Xia; Huang, Zhi; Ling, Bo; Wang, Shao-Jin

    2016-01-01

    Knowledge of bacteria's heat resistance is essential for developing effective thermal treatments. Choosing an appropriate test method is important to accurately determine bacteria's heat resistances. Although being a major factor to influence the thermo-tolerance of bacteria, the heating rate in samples cannot be controlled in water or oil bath methods due to main dependence on sample's thermal properties. A heating block system (HBS) was designed to regulate the heating rates in liquid, semi-solid and solid foods using a temperature controller. Distilled water, apple juice, mashed potato, almond powder and beef were selected to evaluate the HBS's performance by experiment and computer simulation. The results showed that the heating rates of 1, 5 and 10 °C/min with final set-point temperatures and holding times could be easily and precisely achieved in five selected food materials. A good agreement in sample central temperature profiles was obtained under various heating rates between experiment and simulation. The experimental and simulated results showed that the HBS could provide a sufficiently uniform heating environment in food samples. The effect of heating rate on bacterial thermal resistance was evaluated with the HBS. The system may hold potential applications for rapid and accurate assessments of bacteria's thermo-tolerances. PMID:27465120

  1. Pneumonia - adults (community acquired)

    ... breathing (respiratory) condition in which there is an infection of the lung. This article covers community-acquired pneumonia (CAP). This type of pneumonia is found in persons who have not recently been in the hospital or another health care facility such as a ...

  2. Etiopathology of acquired cholesteatoma

    Prabodh Karnik

    2011-01-01

    Full Text Available The etiopathology of acquired cholesteatoma has undergone numerous changes over the past 150 years. However, certain facts stand out with clarity. The presence of cytokeratins in acquired cholesteatoma, which are akin to those found in the tympanic membrane and external auditory canal, shows that these are probably the site of origin of acquired cholesteatoma. The cholesteatoma sac also shows its greatest growth at its tympanic membrane attachment into the middle ear. Implantations of squamous epithelium due to trauma or surgery could be another originating factor. The basic pathology is the formation of papillary cones from the tympanic membrane or external auditory canal, which progress from microcholesteatoma to frank cholesteatoma with keratin collections. There is an altered matrix metalloproteinase pathway. Tumor necrosis factor activation with altered wound healing process contributes to the collateral destruction of bone. Trisomy and aneuploidy of chromosome 8 predispose to cholesteatoma formation in affected individuals. In this article, we present the etiopathology of acquired cholesteatoma as it stands today.

  3. Acquired cystic kidney disease

    Choyke, P.L. [National Institutes of Health, Bethesda, MD (United States). Dept. of Diagnostic Radiology

    2000-11-01

    Acquired cystic kidney disease (ACKD), also known as acquired renal cystic disease (ARCD,) occurs in patients who are on dialysis for end-stage renal disease. It is generally accepted that ACKD develops as a consequence of sustained uremia and can first manifest even before dialysis is initiated while the patient is still in chronic renal failure. The role of immune suppression, particularly in transplant recipients, in the development of ACKD, is still under investigation. The prevalence of ACKD is directly related to the duration of dialysis and the risk of cancer is directly related to the presence of cysts. Herein we review the current understanding of the pathophysiology and imaging implications of ACKD. (orig.)

  4. Acquired cystic kidney disease

    Acquired cystic kidney disease (ACKD), also known as acquired renal cystic disease (ARCD,) occurs in patients who are on dialysis for end-stage renal disease. It is generally accepted that ACKD develops as a consequence of sustained uremia and can first manifest even before dialysis is initiated while the patient is still in chronic renal failure. The role of immune suppression, particularly in transplant recipients, in the development of ACKD, is still under investigation. The prevalence of ACKD is directly related to the duration of dialysis and the risk of cancer is directly related to the presence of cysts. Herein we review the current understanding of the pathophysiology and imaging implications of ACKD. (orig.)

  5. Acquired epidermolysis bullosa

    Maricel Sucar Batista; Yanier Serrano García; Taimí Miranda Vergara

    2015-01-01

    Epidermolysis bullosa is a group of diseases or skin disorders genetically transmitted and it is characterized by the appearance of bullae, ulcers and skin wounds. It usually appears at birth or in the first months of life. This is a case of a 72-year-old female patient who comes to the dermatology department with skin lesions of 6 months of evolution. A skin biopsy was performed, taking a sample for direct and indirect immunofluorescence. Acquired epidermolysis bullosa of unknown etiology wa...

  6. Acquired hypertrichosis lanuginosa

    Kumar Pramod

    1993-01-01

    Full Text Available Acquired hypertirichosis lanuginose developed rapidly in a patient with no detectable malignancy. Soft, fine, downy hair growth was noticed on the face, ears, limbs and trunk. Bilaterally symmetrical vitiliginous macules were present on the ear and preauricular region. This case is reported because of its rarity, absence of any detectable malignancy and development of vitiligo, which to our knowledge has not been reported earlier.

  7. AIDS: acquired immunodeficiency syndrome

    Gilmore, N. J.; Beaulieu, R.; Steben, M.; Laverdière, M.

    2002-01-01

    Acquired immunodeficiency syndrome, or AIDS, is a new illness that occurs in previously healthy individuals. It is characterized by immunodeficiency, opportunistic infections and unusual malignant diseases. Life-threatening single or multiple infections with viruses, mycobacteria, fungi or protozoa are common. A rare neoplasm, Kaposi's sarcoma, has developed in approximately one third of patients with AIDS. More than 800 cases of AIDS have been reported in North America, over 24 of them in Ca...

  8. Learning-By-Being-Acquired

    Colombo, Massimo G.; Moreira, Solon; Rabbiosi, Larissa

    -categorization theories, we argue that R&D team reorganization increases the acquired inventors’ use of the prior stock of technological knowledge of the acquiring firm after the acquisition. Furthermore, this effect is enhanced if acquired inventors have higher innovation ability relative to their acquiring peers but is...

  9. Acquired von Willebrand Syndrome

    郭涛

    2005-01-01

    @@ Acquired von Willebrand syndrome (AvWS) is kind of bleeding disorder with laboratory findings similar to those in congenital yon Willebrand disease (vWD).AvWS doesn's have any personal or family history of bleeding, but is associated with certain diseases or abnormal conditions or drugs. Although AvWS is being stated as a rare disease, it has gained more and more attention during the past years. Not because of the severity of the disease, but it is more common than we thought and most patients don' t have a proper diagnosis.

  10. Acquired epidermolysis bullosa

    Maricel Sucar Batista

    2015-12-01

    Full Text Available Epidermolysis bullosa is a group of diseases or skin disorders genetically transmitted and it is characterized by the appearance of bullae, ulcers and skin wounds. It usually appears at birth or in the first months of life. This is a case of a 72-year-old female patient who comes to the dermatology department with skin lesions of 6 months of evolution. A skin biopsy was performed, taking a sample for direct and indirect immunofluorescence. Acquired epidermolysis bullosa of unknown etiology was diagnosed. Treatment was started with low-dose colchicine to increase it later, according to the patient’s tolerance and disease progression.

  11. Acquired Blaschkoid dermatitis

    Mercy P

    2007-01-01

    Full Text Available Acquired Blaschkoid dermatitis characterised by unilateral relapsing inflammatory disease along the lines of Blaschko. A 40-year-old Indian male presented with unilateral erythematous, itchy grouped papules on the left side of the chest, abdomen, back and left arm of 15 days duration. The eruption stopped abruptly at the midline of the torso, completely sparing the right side of the body. The lesions were arranged in whorls and streaks corresponding to the lines of Blaschko. Skin biopsy showed hyperkeratosis and features suggestive of sub-acute spongiotic dermatitis with lymphocytic infiltrate around the blood vessels in the dermis. Patient was diagnosed as a case of Blaschkoid dermatitis. To the best of our knowledge, this is the first case of this condition being reported from India.

  12. Isolation, Production, and Characterization of Thermotolerant Xylanase from Solvent Tolerant Bacillus vallismortis RSPP-15

    Rajeeva Gaur

    2015-01-01

    Full Text Available Sixty bacterial strains isolated from the soils sample in the presence of organic solvent were screened for xylanase production. Among them, strain RSPP-15 showed the highest xylanase activity which was identified as Bacillus vallismortis. The isolate showed maximum xylanase production (3768 U/mL in the presence of birch wood xylan and beef extract at 55°C pH 7.0 within 48 h of incubation. The enzyme activity and stability were increased 181.5, 153.7, 147.2, 133.6, and 127.9% and 138.2, 119.3, 113.9, 109, and 104.5% in the presence of Co2+, Ca2+, Mg+2, Zn+2, and Fe+3 ions (10 mM. Xylanase activity and stability were strongly inhibited in the presence of Hg and Cu ions. The enzyme was also stable in the presence of 30% of n-dodecane, isooctane, n-decane, xylene, toluene, n-hexane, n-butanol, and cyclohexane, respectively. The presence of benzene, methanol, and ethanol marginally reduced the xylanase stability, respectively. This isolate may be useful in several industrial applications owing to its thermotolerant and organic solvent resistance characteristics.

  13. Studies on the biosorption of uranium by a thermotolerant, ethanol-producing strain of Kluyveromyces marxianus

    Bustard, M. [Biotechnology Research Group, School of Applied Biological and Chemical Sciences, University of Ulster, Coleraine, Co. Londonderry, BT52 1SA (United Kingdom); Donnellan, N. [Biotechnology Research Group, School of Applied Biological and Chemical Sciences, University of Ulster, Coleraine, Co. Londonderry, BT52 1SA (United Kingdom); Rollan, A. [Biotechnology Research Group, School of Applied Biological and Chemical Sciences, University of Ulster, Coleraine, Co. Londonderry, BT52 1SA (United Kingdom); McHale, A.P. [Biotechnology Research Group, School of Applied Biological and Chemical Sciences, University of Ulster, Coleraine, Co. Londonderry, BT52 1SA (United Kingdom)

    1997-06-01

    The ability of residual biomass from the thermotolerant ethanol-producing yeast strain Kluyveromyces marxianus IMB3 to function as a biosorbent for uranium has been examined. It was found that the biomass had an observed maximum biosorption capacity of 120 mg U/g dry weight of biomass. The calculated value for the biosorption maximum, obtained by fitting the data to the Langmuir model was found to be 130 mg U/g dry weight biomass. Maximum biosorption capacities were examined at a number of temperatures and both the observed and calculated values obtained for those capacities increased with increasing temperature. Decreasing the pH of the biosorbate solution resulted in a decrease in uptake capacity. When biosorption reactions were carried out using sea-water as the diluent it was found that the maximum biosorption capacity of the biomass increased significantly. Using transmission electron microscopy, uranium crystals were shown to be concentrated on the outer surface of the cell wall, although uranium deposition was also observed in the interior of the cell. (orig.). With 3 figs., 2 tabs.

  14. Studies on the biosorption of uranium by a thermotolerant, ethanol-producing strain of Kluyveromyces marxianus

    The ability of residual biomass from the thermotolerant ethanol-producing yeast strain Kluyveromyces marxianus IMB3 to function as a biosorbent for uranium has been examined. It was found that the biomass had an observed maximum biosorption capacity of 120 mg U/g dry weight of biomass. The calculated value for the biosorption maximum, obtained by fitting the data to the Langmuir model was found to be 130 mg U/g dry weight biomass. Maximum biosorption capacities were examined at a number of temperatures and both the observed and calculated values obtained for those capacities increased with increasing temperature. Decreasing the pH of the biosorbate solution resulted in a decrease in uptake capacity. When biosorption reactions were carried out using sea-water as the diluent it was found that the maximum biosorption capacity of the biomass increased significantly. Using transmission electron microscopy, uranium crystals were shown to be concentrated on the outer surface of the cell wall, although uranium deposition was also observed in the interior of the cell. (orig.). With 3 figs., 2 tabs

  15. Prevalence of thermotolerant Campylobacter in broiler flocks and broiler carcasses in Italy

    Giacomo Migliorati

    2010-12-01

    Full Text Available In accordance with European Union regulations, from 5 February until 15 December 2008, sampling and analysis activities were conducted in Italy to assess the extent of contamination caused by thermotolerant Campylobacter in broiler chickens farmed nationwide. The survey involved 48 poultry slaughterhouses distributed across eleven regions of Italy, where the caeca and carcasses of 393 slaughter batches were sampled. A total of 284 batches (72.3% gave positive results for Campylobacter spp. as follows: 52.1% were contaminated by C. jejuni, 55.6% by C. coli and 1.1% by C. lari. C. jejuni and C. coli were isolated together in 37 batches (13% of positive results. Campylobacter spp. was isolated only from the caeca in 251 slaughter batches (63.9% including caecal isolates of C. jejuni (48.2%, C. coli (50.6%, and C. lari (1.2%. Carcasses from 182 batches (46.3% were contaminated by C. jejuni in 40.7% of cases, C. coli in 57.7% and the absence of C. lari from all batches examined. The contamination level observed in the carcasses ranged between 10 and 1.6 × 107 cfu/g.

  16. Growth tradeoffs associated with thermotolerant symbionts in the coral Pocillopora damicornis are lost in warmer oceans

    Cunning, R.; Gillette, P.; Capo, T.; Galvez, K.; Baker, A. C.

    2015-03-01

    The growth and survival of reef corals are influenced by their symbiotic algal partners ( Symbiodinium spp.), which may be flexible in space and time. Tradeoffs among partnerships exist such that corals with thermotolerant symbionts (e.g., clade D) resist bleaching but grow more slowly, making the long-term ecosystem-level impacts of different host-symbiont associations uncertain. However, much of this uncertainty is due to limited data regarding these tradeoffs and particularly how they are mediated by the environment. To address this knowledge gap, we measured growth and survival of Pocillopora damicornis with thermally sensitive (clade C) or tolerant (clade D) symbionts at three temperatures over 18-55 weeks. Warming reduced coral growth overall, but altered the tradeoffs associated with symbiont type. While clade D corals grew 35-40 % slower than clade C corals at cooler temperatures (26 °C), warming of 1.5-3 °C reduced and eliminated this growth disadvantage. These results suggest that although warmer oceans will negatively impact corals, clade D may enhance survival at no cost to growth relative to clade C. Understanding these genotype-environment interactions can help improve modeling efforts and conservation strategies for reefs under global climate change.

  17. NOVEL SOURCES OF FUNGAL CELLULASES OF THERMOPHILIC / THERMOTOLERANT FOR EFFICIENT DEINKING OF COMPOSITE PAPER WASTE

    Rohit Soni

    2008-02-01

    Full Text Available Twenty thermophilic/thermotolerant fungal strains were isolated from compositing soils and screened for production of different enzymes (Endoglucanases, β-glucosidase, Fpase and xylanases to assess their deinking efficiency. Three isolates, Aspergillus sp. AMA, Aspergillus terreus AN1, and Myceliophthora fergusii T4I, identified on the basis of morphological and sequencing of amplified ITS1-5.8S-ITS2 rDNA region, showed significant deinking of composite waste paper (70% magazine and 30% Xerox copier/ laser print paper waste as well as improved properties (brightness, tensile strength, tear index of recycled paper sheets. The chosen strains Aspergillus sp. AMA, Aspergillus terreus AN1 and Myceliophthora fergusii T4I, showed 53, 52.7, and 40.32% deinking with increase in brightness by 4.32, 3.56, and 3.01 % ISO, respectively. These cultures were found to produce multiple endoglucanases and were characterized to lack a cellulose binding module (CBD, which may be responsible for their better deinking efficiency.

  18. Purification and Characterization of Organic Solvent and Detergent Tolerant Lipase from Thermotolerant Bacillus sp. RN2

    Tadahiko Kajiwara

    2010-09-01

    Full Text Available The aim of this study was to characterize the organic solvent and detergent tolerant properties of recombinant lipase isolated from thermotolerant Bacillus sp. RN2 (Lip-SBRN2. The isolation of the lipase-coding gene was achieved by the use of inverse and direct PCR. The complete DNA sequencing of the gene revealed that the lip-SBRN2 gene contains 576 nucleotides which corresponded to 192 deduced amino acids. The purified enzyme was homogeneous with the estimated molecular mass of 19 kDa as determined by SDS-PAGE and gel filtration. The Lip-SBRN2 was stable in a pH range of 9–11 and temperature range of 45–60 °C. The enzyme was a non metallo-monomeric protein and was active against pNP-caprylate (C8 and pNP-laurate (C12 and coconut oil. The Lip-SBRN2 exhibited a high level of activity in the presence of 108% benzene, 102.4% diethylether and 112% SDS. It is anticipated that the organic solvent and detergent tolerant enzyme secreted by Bacillus sp. RN2 will be applicable as catalysts for reaction in the presence of organic solvents and detergents.

  19. ISOLATION AND IDENTIFICATION OF A THERMOTOLERANT PLANT GROWTH PROMOTING PSEUDOMONAS PUTIDA PRODUCING TREHALOSE SYNTHASE

    Ali Sk.Z.

    2013-08-01

    Full Text Available A thermotolerant plant growth promoting Pseudomonas isolate growing at 40oC producing trehalose synthase (TreS was isolated from rhizosphere soil under semi arid conditions of India. Trehalose synthase was extracted; purified and enzymatic activity was examined at various temperatures and pH. The optimum temperature and pH was 38oC and pH 7.5 and the activity declined at above or below the optimum pH and temperature. The enzyme was active on maltose and trehalose among saccharides tested. The enzyme had a higher catalytic activity for maltose with a trehalose yield of 72% than for trehalose where 30% yield of maltose was achieved, indicating maltose as preferred substrate. The isolate showed multiple plant growth promoting traits (indole acetic acid (IAA, phosphate solubilization, siderophore and ammonia both at ambient (28oC and high temperature (40oC. Based on phenotypic and 16SrRNA analysis the isolate was identified as Pseudomonas putida (Accession No. GU396283.

  20. Intercontrole acquiring by Framatome

    The Framatome group, as the worldwide leader in nuclear power plant construction, has reinforced his competences in nuclear services thanks to the acquiring of the Intercontrole company, specialized in non-destructive testing in nuclear and industrial environments. After a presentation of the functioning principle and of the safety aspects of a PWR reactor, this press dossier presents in a first part the role of nuclear services and in particular of non-destructive testing in nuclear power plants (in-service inspection, regulatory aspects, testing processes). This part is illustrated with some examples of inspection performed on some components of the primary coolant loop (steam generators, reactor vessel, pressurizer, pipes, primary pumps). A second part presents the technical centres and units of Framatome in charge of performing non-destructive inspections, while a third part describes the industrial policy and strategy of the group in this domain (market of nuclear park maintenance in France, in the USA and worldwide, creation of the 'inspection and control' centre of Framatome). A last part presents the activities of the Intercontrole company and of its daughter companies with some examples of actions realized in the nuclear and natural gas domains. (J.S.)

  1. A new search for thermotolerant yeasts, its characterization and optimization using response surface methodology for ethanol production

    Richa eArora

    2015-09-01

    Full Text Available The progressive rise in energy crisis followed by green house gas (GHG emissions is serving as the driving force for bioethanol production from renewable resources. Current bioethanol research focuses on lignocellulosic feedstocks as these are abundantly available, renewable, sustainable and exhibit no competition between the crops for food and fuel. However, the technologies in use have some drawbacks including incapability of pentose fermentation, reduced tolerance to products formed, costly processes, etc. Therefore, the present study was carried out with the objective of isolating hexose and pentose fermenting thermophilic/ thermotolerant ethanologens with acceptable product yield. Two thermotolerant isolates, NIRE-K1 and NIRE-K3 were screened for fermenting both glucose and xylose and identified as Kluyveromyces marxianus NIRE-K1 and K. marxianus NIRE-K3. After optimization using FCCD (Face-centered Central Composite Design, the growth parameters like temperature and pH were found to be 45.17 oC and 5.49, respectively for K. marxianus NIRE-K1 and 45.41 oC and 5.24, respectively for K. marxianus NIRE-K3. Further, batch fermentations were carried out under optimized conditions, where K. marxianus NIRE-K3 was found to be superior over K. marxianus NIRE-K1. Ethanol yield (Yx/s, sugar to ethanol conversion rate (%, microbial biomass concentration (X and volumetric product productivity (Qp obtained by K. marxianus NIRE-K3 were found to be 9.3%, 9.55%, 14.63% and 31.94% higher than that of K. marxianus NIRE-K1, respectively. This study revealed the promising potential of both the screened thermotolerant isolates for bioethanol production.

  2. Hyperthermia combined with 5-fluorouracil promoted apoptosis and enhanced thermotolerance in human gastric cancer cell line SGC-7901

    Liu T

    2015-05-01

    Full Text Available Tao Liu,* Yan-Wei Ye,* A-li Zhu, Zhen Yang, Yang Fu, Chong-Qing Wei, Qi Liu, Chun-Lin Zhao, Guo-Jun Wang, Xie-Fu Zhang Department of Gastrointestinal Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, People’s Republic of China *These authors contributed equally to this work Abstract: This study was designed to investigate the proliferation inhibition and apo­ptosis-promoting effect under hyperthermia and chemotherapy treatment, at cellular level. Human gastric cancer cell line SGC-7901 was cultivated with 5-fluorouracil at different temperatures. Cell proliferation and apoptosis were determined, and expression of Bcl-2 and HSP70 was measured at different treatments. Cell survival rates and inhibition rates in chemotherapy group, thermotherapy group, and thermo-chemotherapy group were drastically lower than the control group (P<0.05. For tumor cells in the thermo-chemotherapy group, survival rates and inhibition rates at three different temperatures were all significantly lower than those in chemotherapy group and thermotherapy group (P<0.05. 5-Fluorouracil induced apoptosis of SGC-7901 cells with a strong temperature dependence, which increased gradually with increase in temperature. At 37°C and 43°C there were significant differences between the thermotherapy group and chemotherapy group and between the thermo-chemotherapy group and thermotherapy group (P<0.01. The expression of Bcl-2 was downregulated and HSP70 was upregulated, with increase in temperature in all groups. Cell apoptosis was not significant at 46°C (P>0.05, which was probably due to thermotolerance caused by HSP70 accumulation. These results suggested that hyperthermia combined with 5-fluorouracil had a synergistic effect in promoting apoptosis and enhancing thermotolerance in gastric cancer cell line SGC-7901. Keywords: gastric cancer, thermotherapy, 5-fluorouracil, Bcl-2, HSP70, thermotolerance

  3. Thermotolerant Yeast Strains Adapted by Laboratory Evolution Show Trade-Off at Ancestral Temperatures and Preadaptation to Other Stresses

    Caspeta, Luis; Nielsen, Jens

    2015-01-01

    adaptive laboratory evolution, we previously isolated seven Saccharomyces cerevisiae strains with improved growth at 40°C. Here, we show that genetic adaptations to high temperature caused a growth trade-off at ancestral temperatures, reduced cellular functions, and improved tolerance of other stresses...... proteins showed that the lethal temperature for yeast is around 49°C, as a large fraction of the yeast proteins denature above this temperature. Our analysis also indicated that the number of functions involved in controlling the growth rate decreased in the thermotolerant strains compared with the number...

  4. 双孢蘑菇耐温差异蛋白质组学研究%Differential Proteomics Studies on Thermotolerance of Agaricus bisporus

    陆兆明; 徐祯; 王珂; 陈澄; 陈岑渌璐; 宋思扬

    2009-01-01

    利用蛋白质组学和荧光定量PCR方法,研究双孢蘑菇(Agaricus bisporus Lange (Imbach))02菌株在常温与高温胁迫下的蛋白质表达差异,发现了6个差异蛋白质点,经NCBI数据库比对分析,表明6个差异蛋白质分别为HSP70家族的HSS1热激蛋白、异柠檬酸裂解酶、细胞色素P450单氧化酶及3个未知蛋白质.这些蛋白质在双孢蘑菇受热胁迫下具有保护自身稳定的功能.%Agaricus bisporus is a kind of cultivated edible mushroom which has high economic value and important ecology significance.Environment temperature is the main restrained factor in its development,and this greatly limits its cultivation season. In this study,2D-eletrophoresis and real-time PCR are employed to discover the proteomic difference in Agaricus bisporus 02 strain after high temperature induction,and 6 differential expressed protein spots were finally obtained.Compared with the NCBI data base ,spot 1 is the heat shock protein ,spot 2 is isocitrate lyase and spot 3 is cytochrome P450 monooxygenase.The other three spots are novel.Presumably,those proteins confer the thermotolerance on strain 02 under high temperature.

  5. Decolorization of a recalcitrant organic compound (Melanoidin by a novel thermotolerant yeast, Candida tropicalis RG-9

    Tiwari Soni

    2012-06-01

    Full Text Available Abstract Background Sugarcane distilleries use molasses for ethanol production and generate large volume of effluent containing high biological oxygen demand (BOD and chemical oxygen demand (COD along with melanoidin pigment. Melanoidin is a recalcitrant compound that causes several toxic effects on living system, therefore, may be treated before disposal. The aim of this study was to isolate a potential thermotolerant melanoidin decolorizing yeast from natural resources, and optimized different physico-chemical and nutritional parameters. Results Total 24 yeasts were isolated from the soil samples of near by distillery site, in which isolate Y-9 showed maximum decolorization and identified as Candida tropicalis by Microbial Type Culture Collection (MTCC Chandigarh, India. The decolorization yield was expressed as the decrease in the absorbance at 475 nm against initial absorbance at the same wavelength. Uninoculated medium served as control. Yeast showed maximum decolorization (75% at 45°C using 0.2%, glucose; 0.2%, peptone; 0.05%, MgSO4; 0.01%, KH2PO4; pH-5.5 within 24 h of incubation under static condition. Decolorizing ability of yeast was also confirmed by high performance liquid chromatography (HPLC analysis. Conclusion The yeast strain efficiently decolorized melanoidin pigment of distillery effluent at higher temperature than the other earlier reported strains of yeast, therefore, this strain could also be used at industrial level for melanoidin decolorization as it tolerated a wide range of temperature and pH with very small amount of carbon and nitrogen sources.

  6. Cloning, Expression, and Characterization of Thermotolerant Manganese Superoxide Dismutase from Bacillus sp. MHS47

    Supatra Areekit

    2011-01-01

    Full Text Available A superoxide dismutase gene from thermotolerant Bacillus sp. MHS47 (MnSOD47 was cloned, sequenced, and expressed. The gene has an open reading frame of 612 bp, corresponding to 203 deduced amino acids, with high homology to the amino acid sequences of B. thuringiensis (accession no. EEN01322, B. anthracis (accession no. NP_846724, B. cereus (accession no. ZP_04187911, B. weihenstephanensis (accession no. YP_001646918, and B. pseudomycoides. The conserved manganese-binding sites (H28, H83, D165, and H169 show that MnSOD47 has the specific characteristics of the manganese superoxide dismutase (MnSOD enzymes. MnSOD47 expressed an enzyme with a molecular weight of approximately 22.65 kDa and a specific activity of 3537.75 U/mg. The enzyme is active in the pH range 7–8.5, with an optimum pH of 7.5, and at temperatures in the range 30–45 °C, with an optimum temperature of 37 °C. Tests of inhibitors and metal ions indicated that the enzyme activity is inhibited by sodium azide, but not by hydrogen peroxide or potassium cyanide. These data should benefit future studies of MnSODs in other microorganisms and the biotechnological production of MnSOD47, and could also be used to develop a biosensor for the detection of antioxidants and free radical activity. In the future, this basic knowledge could be applicable to the detection of cancer risks in humans and therapeutic treatments.

  7. Biosorption of heavy metal by thermotolerant polymerproducing bacterial cells and the bioflocculant

    Saithong Kaewchai

    2002-07-01

    Full Text Available Three strains of thermotolerant polymer-producing bacteria; Bacillus subtilis WD 90, Bacillus subtilis SM 29, and Enterobacter agglomerans SM 38 as well as their biofloculants were used to investigate on the adsorption of heavy metal, nickel and cadmium. The effects of pH and concentrations of heavy metal were investigated. The optimum pH for nickel and cadmium adsorption by the dried cells of E. agglomerans SM 38 were found to be 7.0 (25.5% removal and 8.0 (32% removal, respectively. For B. subtilis WD 90 and B. subtilis SM 29, the optimum pH at 8.0 exhibited the nickel removal of 27% and 25%, respectively, and cadmium removal of 28% and 28.5%, respectively. The heavy metal adsorption by the dried cells and wet cells of E. agglomerans SM 38 were slightly increased with increasing initial concentrations of nickel and cadmium up to 60 and 30 ppm, respectively. The bioflocculant of B. subtilis WD 90 and B. subtilis SM 29 showed the highest nickel removal of 90.7% and 87.0% respectively, while the cadmium removal was 90.9 and 91.4%, respectively. The optimum pH for adsorption of both nickel and cadmium by the bioflocculant of E. agglomerans SM 38 was 7.0 with the removal of 92.8 and 84.2%, respectively. The optimum nickel concentration for adsorption by the bioflocculant of E. agglomerans SM 38 was 10 ppm, with the removal of 92.5%, and rather stable up to 60 ppm. The optimum cadmium concentration for adsorption by the bioflocculant of B. subtilis SM 29 was 60 ppm at pH 8.0 with the removal of 85.7%. Therefore, the bioflocculant of the three isolates gave higher heavy metal adsorption than the cells.

  8. Bioprocessing of bagasse hydrolysate for ethanol and xylitol production using thermotolerant yeast.

    Kumar, Sachin; Dheeran, Pratibha; Singh, Surendra P; Mishra, Indra M; Adhikari, Dilip K

    2015-01-01

    Fermentation of xylose-rich and glucose-rich bagasse hydrolysates, obtained from the two-stage acid hydrolysis was studied using the thermotolerant yeast Kluyveromyces sp. IIPE453. The yeast could grow on xylose-rich hydrolysate at 50 °C with the dry cell weight, cell mass yield and maximum specific growth rate of 5.35 g l(-1), 0.58 g g(-1) and 0.13 h(-1), respectively. The yeast was found to be very promising for ethanol as well as xylitol production from the sugars obtained from the lignocellulosic biomass. Batch fermentations of xylose-rich and glucose-rich hydrolysates yielded 0.61 g g(-1) xylitol and 0.43 g g(-1) ethanol in the broth, respectively based on the sugars present in the hydrolysate. Overall ethanol yield of 165 g (210 ml) and 183 g xylitol per kg of bagasse was obtained, when bagasse hydrolysate was used as a substrate. Utilization of both the glucose and xylose sugars makes the process most economical by producing both ethanol and xylitol based on biorefinery concept. On validating the experimental data of ethanol fermentation, the modified Luong kinetic model for product inhibition as well as inhibition due to inhibitory compounds present in hydrolysate, the model was found to be the best fit for ethanol formation from bagasse hydrolysate using Kluyveromyces sp. IIPE453. PMID:25090978

  9. Matriconditioning Improves Thermotolerance in Pepper Seeds through Increased in 1-Aminocyclopropane-1-Carboxylic Acid Synthesis and Utilization

    SATRIYAS ILYAS

    2006-03-01

    Full Text Available Matriconditioning using a solid carrier, Micro-Cel E, was applied on pepper seeds and its effects on the improvement of thermotolerance through the ethylene biosynthesis were studied. Untreated and matriconditioned seeds were soaked in 5 mM 1-aminocyclopropane-1-carboxylic acid (ACC for various time at 25 oC to studies the time course of ACC-derived ethylene production. To study the performance of the seeds at high temperature, they were planted at temperature regime of 35 oC, 12h light/27 oC, 12h dark. The ACC-oxidase activity of the seeds after incubated in ACC at 35 oC was also determined. The ACC contents in untreated and matriconditioned seeds during the 24h imbibition period at 35 oC were monitored. No ethylene was detected during soaking of pepper seeds in the absence of ACC. In 5 mM ACC detectable levels of ethylene were produced; the matriconditioned seeds producing 10-fold larger amounts than the untreated seeds at the time of germination. It is postulated that matriconditioning greatly increases the ACC-oxidase activity at the time of germination. Matriconditioned seeds imbibed at 35 oC produced larger amounts of ACC and greater ACC-oxidase activity than the untreated seeds. Thus, the basis for the thermotolerance by matriconditioned seeds may be increasing ability to synthesize ACC and to utilize it for ethylene production and stress alleviation.

  10. Thermotolerant Kluyveromyces marxianus and Saccharomyces cerevisiae strains representing potentials for bioethanol production from Jerusalem artichoke by consolidated bioprocessing

    Hu, Nan [Agricultural Univ., Qingdao, SD (China). College of Animal Science and Technology; Chinese Academy of Sciences, Qingdao, SD (China). Key Lab. of Biofuels; Yuan, Bo; Wang, Shi-An; Li, Fu-Li [Chinese Academy of Sciences, Qingdao, SD (China). Key Lab. of Biofuels; Sun, Juan [Agricultural Univ., Qingdao, SD (China). College of Animal Science and Technology

    2012-09-15

    Thermotolerant inulin-utilizing yeast strains are desirable for ethanol production from Jerusalem artichoke tubers by consolidated bioprocessing (CBP). To obtain such strains, 21 naturally occurring yeast strains isolated by using an enrichment method and 65 previously isolated Saccharomyces cerevisiae strains were investigated in inulin utilization, extracellular inulinase activity, and ethanol fermentation from inulin and Jerusalem artichoke tuber flour at 40 C. The strains Kluyveromyces marxianus PT-1 (CGMCC AS2.4515) and S. cerevisiae JZ1C (CGMCC AS2.3878) presented the highest extracellular inulinase activity and ethanol yield in this study. The highest ethanol concentration in Jerusalem artichoke tuber flour fermentation (200 g L{sup -1}) at 40 C achieved by K. marxianus PT-1 and S. cerevisiae JZ1C was 73.6 and 65.2 g L{sup -1}, which corresponded to the theoretical ethanol yield of 90.0 and 79.7 %, respectively. In the range of 30 to 40 C, temperature did not have a significant effect on ethanol production for both strains. This study displayed the distinctive superiority of K. marxianus PT-1 and S. cerevisiae JZ1C in the thermotolerance and utilization of inulin-type oligosaccharides reserved in Jerusalem artichoke tubers. It is proposed that both K. marxianus and S. cerevisiae have considerable potential in ethanol production from Jerusalem artichoke tubers by a high temperature CBP. (orig.)

  11. Divergent distribution of the sensor kinase CosS in non-thermotolerant campylobacter species and its functional incompatibility with the response regulator CosR of Campylobacter jejuni.

    Sunyoung Hwang

    Full Text Available Two-component signal transduction systems are commonly composed of a sensor histidine kinase and a cognate response regulator, modulating gene expression in response to environmental changes through a phosphorylation-dependent process. CosR is an OmpR-type response regulator essential for the viability of Campylobacter jejuni, a major foodborne pathogenic species causing human gastroenteritis. Although CosR is a response regulator, its cognate sensor kinase has not been identified in C. jejuni. In this study, DNA sequence analysis of the cosR flanking regions revealed that a gene encoding a putative sensor kinase, which we named cosS, is prevalent in non-thermotolerant Campylobacter spp., but not in thermotolerant campylobacters. Phosphorylation assays indicated that C. fetus CosS rapidly autophosphorylates and then phosphorylates C. fetus CosR, suggesting that the CosRS system constitutes a paired two-component signal transduction system in C. fetus. However, C. fetus CosS does not phosphorylate C. jejuni CosR, suggesting that CosR may have different regulatory cascades between thermotolerant and non-thermotolerant Campylobacter species. Comparison of CosR homolog amino acid sequences showed that the conserved phosphorylation residue (D51, which is present in all non-thermotolerant Campylobacter spp., is absent from the CosR homologs of thermotolerant Campylobacter species. However, C. jejuni CosR was not phosphorylated by C. fetus CosS even after site-directed mutagenesis of N51D, implying that C. jejuni CosR may possibly function phosphorylation-independently. In addition, the results of cosS mutational analysis indicated that CosS is not associated with the temperature dependence of the Campylobacter spp. despite its unique divergent distribution only in non-thermotolerant campylobacters. The findings in this study strongly suggest that thermotolerant and non-thermotolerant Campylobacter spp. have different signal sensing mechanisms

  12. Moderate Heat Challenge Increased Yolk Steroid Hormones and Shaped Offspring Growth and Behavior in Chickens

    Aline Bertin; Marine Chanson; Joël Delaveau; Frédéric Mercerand; Erich Möstl; Ludovic Calandreau; Cécile Arnould; Christine Leterrier; Anne Collin

    2013-01-01

    BACKGROUND: Environmental challenges might affect the maternal organism and indirectly affect the later ontogeny of the progeny. We investigated the cross-generation impact of a moderate heat challenge in chickens. We hypothesized that a warm temperature--within the thermotolerance range--would affect the hormonal environment provided to embryos by mothers, and in turn, affect the morphology and behavioral phenotype of offspring. METHODOLOGY/PRINCIPAL FINDINGS: Laying hens were raised under a...

  13. Toward an international standard for PCR-based detection of food-borne thermotolerant campylobacters: Validation in a multicenter collaborative trial

    Lübeck, Peter Stephensen; Cook, N.; Wagner, M.;

    2003-01-01

    As part of a European research project, the performance of a PCR assay to detect food-borne thermotolerant campylobacters (Campylobacter jejuni, C. coli, and C. lari) was evaluated through an international collaborative trial involving 12 participating laboratories. DNA from 10 target and 8...

  14. Differential response of aspen and birch trees to heat stress under elevated carbon dioxide

    The effect of high temperature on photosynthesis of isoprene-emitting (aspen) and non-isoprene-emitting (birch) trees were measured under elevated CO2 and ambient conditions. Aspen trees tolerated heat better than birch trees and elevated CO2 protected photosynthesis of both species against moderate heat stress. Elevated CO2 increased carboxylation capacity, photosynthetic electron transport capacity, and triose phosphate use in both birch and aspen trees. High temperature (36-39 deg. C) decreased all of these parameters in birch regardless of CO2 treatment, but only photosynthetic electron transport and triose phosphate use at ambient CO2 were reduced in aspen. Among the two aspen clones tested, 271 showed higher thermotolerance than 42E possibly because of the higher isoprene-emission, especially under elevated CO2. Our results indicate that isoprene-emitting trees may have a competitive advantage over non-isoprene emitting ones as temperatures rise, indicating that biological diversity may be affected in some ecosystems because of heat tolerance mechanisms. - We report that elevated CO2 confers increased thermotolerance on both aspen and birch trees while isoprene production in aspen confers further thermotolerance in aspen.

  15. And the Winner is - Acquired

    Henkel, Joachim; Rønde, Thomas; Wagner, Marcus

    2015-01-01

    New entrants to a market tend to be superior to incumbents in originating radical innovations. We provide a new explanation for this phenomenon, based on markets for technology. It applies in industries where successful entrepreneurial firms, or their technologies, are acquired by incumbents that...... lower probability accompanies higher value in case of success—that is, a more radical innovation. In the second stage, successful entrants bid to be acquired by the incumbent. We assume that entrants cannot survive on their own, so being acquired amounts to a prize in a contest. We identify an...

  16. Ethanol fermentation by the thermotolerant yeast, Kluyveromyces marxianus TISTR5925, of extracted sap from old oil palm trunk

    Yoshinori Murata

    2015-05-01

    Full Text Available Palm sap extracted from old oil palm trunks was previously found to contain sugar and nutrients (amino acids and vitamins. Some palm saps contain a low content of sugar due to differences in species or in plant physiology. Here we condensed palm sap with a low content of sugar using flat membrane filtration, then fermented the condensed palm sap at high temperature using the thermotolerant, high ethanol-producing yeast, Kluyveromyces marxianus. Ethanol production under non-optimum conditions was evaluated. Furthermore, the energy required to concentrate the palm sap, and the amount of energy that could be generated from the ethanol, was calculated. The condensation of sugar in sap from palm trunk required for economically viable ethanol production was evaluated.

  17. Ethanol Production Kinetics by a Thermo-Tolerant Mutant of Saccharomyces Cerevisiae from Starch Industry Waste (Hydrol

    Farman Ali Shah

    2010-06-01

    Full Text Available A thermo-tolerant and deoxyglucose-resistant mutant of Saccharomyces cerevisiae was developed and employed to convert them to fuel ethanol in a 150 litre fermenter. Maximum ethanol production was achieved when fermentation of dextrozyme- treated hydrol was carried out for about 36 hours under optimized fermenting conditions. The maximum specific ethanol production rate (qP, and overall ethanol yield (YP/S were found to be 2.82 g L-1 h-1 and 0.49 g/g respectively. Determination of activation energy for cell growth (Ea= 20.8 kJ/mol and death (Ed = 19.1 kJ/mol and product formation and inactivation (EP=35.8 kJ/mol and Edp = 33.5 kJ/mol revealed the thermo-stability of the organism for up to 47°C.

  18. Ethanol production kinetics by a thermo-tolerant mutant of saccharomyces cerevisiae from starch industry waste (hydrol)

    A thermo-tolerant and deoxyglucose-resistant mutant of Saccharomyces cerevisiae was developed and employed to convert them to fuel ethanol in a 150 litre fermenter. Maximum ethanol production was achieved when fermentation of dextrozyme- treated hydrol was carried out for about 36 hours under optimized fermenting conditions. The maximum specific ethanol production rate (qP), and overall ethanol yield (YP/S) were found to be 2.82 g L/sup -1/ h/sup -1/ and 0.49 g/g respectively. Determination of activation energy for cell growth (Ea= 20.8 kJ/mol) and death (Ed = 19.1 kJ/mol) and product formation and inactivation (EP=35.8 kJ/mol and Edp = 33.5 kJ/mol) revealed the thermo-stability of the organism for up to 47 deg. C. (author)

  19. Adenovirus, enterovirus and thermotolerant coliforms in recreational waters from Lake Guaíba beaches, Porto Alegre, Brazil.

    Maurer, C P; Simonetti, A B; Staggemeier, R; Rigotto, C; Heinzelmann, L S; Spilki, F R

    2015-12-01

    In the present study, molecular detection of human adenoviruses (HAdV) and enteroviruses (EV) was performed in surface water samples collected from beaches Ipanema and Lami, located on the shores of Lake Guaíba, city of Porto Alegre, RS, southern Brazil. Furthermore, water safety was evaluated by counting thermotolerant coliforms (TC), following local government regulations. A total of 36 samples were collected monthly from six different sites along the beaches. Viral genomes were found in 30 (83.3%) samples. The higher detection rate was observed for HAdV (77.8%), followed by EV (22.2%). Although low concentrations of TC have been found, the occurrence of viral genomes in water samples was frequent and may pose a potential risk of infection for people bathing in these beaches. PMID:26608773

  20. Reassembly and protection of small nuclear ribonucleoprotein particles by heat shock proteins in yeast cells.

    Bracken, A P; Bond, U

    1999-01-01

    The process of mRNA splicing is sensitive to in vivo thermal inactivation, but can be protected by pretreatment of cells under conditions that induce heat-shock proteins (Hsps). This latter phenomenon is known as "splicing thermotolerance". In this article we demonstrate that the small nuclear ribonucleoprotein particles (snRNPs) are in vivo targets of thermal damage within the splicing apparatus in heat-shocked yeast cells. Following a heat shock, levels of the tri-snRNP (U4/U6.U5), free U6 ...

  1. Errors in macromolecular synthesis after stress : a study of the possible protective role of the small heat shock proteins

    Marin Vinader, L.

    2006-01-01

    The general goal of this thesis was to gain insight in what small heat shock proteins (sHsps) do with respect to macromolecular synthesis during a stressful situation in the cell. It is known that after a non-lethal heat shock, cells are better protected against a subsequent more severe heat shock, a phenomenon known as thermotolerance and attributed to the presence of the heat shock proteins. The question we asked first is whether the error rate in macromolecular synthesis (transcription, RN...

  2. Acquiring taste in home economics?

    Stenbak Larsen, Christian

    2015-01-01

    that the pupils were encouraged to use their senses: listen to things frying, touch the meat to check if it was done and taste the food in the process of seasoning it. But while some children learned what the teachers expected: to produce well tasting food, others learned to cook very salty and hot food...... appreciated by the group of boys, and others again learned to stick with their idiosyncrasies when pressured by the teacher. Conclusions: Children were acquiring taste in the home economic lessons, but not only the kind of tastes that the teacher had planned for. This leads to reflections on the very complex...... process of taste acquiring and to a call for further research into taste acquiring in complex real life contexts as home economics lessons....

  3. Calcium/calmodulin kinase1 and its relation to thermotolerance and HSP90 in Sporothrix schenckii: an RNAi and yeast two-hybrid study

    Gonzalez-Mendez Ricardo

    2011-07-01

    Full Text Available Abstract Background Sporothrix schenckii is a pathogenic dimorphic fungus of worldwide distribution. It grows in the saprophytic form with hyaline, regularly septated hyphae and pyriform conidia at 25°C and as the yeast or parasitic form at 35°C. Previously, we characterized a calcium/calmodulin kinase in this fungus. Inhibitors of this kinase were observed to inhibit the yeast cell cycle in S. schenckii. Results The presence of RNA interference (RNAi mechanism in this fungus was confirmed by the identification of a Dicer-1 homologue in S. schenckii DNA. RNAi technology was used to corroborate the role of calcium/calmodulin kinase I in S. schenckii dimorphism. Yeast cells were transformed with the pSilent-Dual2G (pSD2G plasmid w/wo inserts of the coding region of the calcium/calmodulin kinase I (sscmk1 gene. Transformants were selected at 35°C using resistance to geneticin. Following transfer to liquid medium at 35°C, RNAi transformants developed as abnormal mycelium clumps and not as yeast cells as would be expected. The level of sscmk1 gene expression in RNAi transformants at 35°C was less than that of cells transformed with the empty pSD2G at this same temperature. Yeast two-hybrid analysis of proteins that interact with SSCMK1 identified a homologue of heat shock protein 90 (HSP90 as interacting with this kinase. Growth of the fungus similar to that of the RNAi transformants was observed in medium with geldanamycin (GdA, 10 μM, an inhibitor of HSP90. Conclusions Using the RNAi technology we silenced the expression of sscmk1 gene in this fungus. RNAi transformants were unable to grow as yeast cells at 35°C showing decreased tolerance to this temperature. The interaction of SSCMK1 with HSP90, observed using the yeast two-hybrid assay suggests that this kinase is involved in thermotolerance through its interaction with HSP90. SSCMK1 interacted with the C terminal domain of HSP90 where effector proteins and co-chaperones interact. These

  4. Acquired Aplastic Anemia in Children

    Hartung, Helge D.; Olson, Timothy S.; Bessler, Monica

    2013-01-01

    This article provides a practice-based and concise review of the etiology, diagnosis, and management of acquired aplastic anemia in children. Bone marrow transplantation, immunosuppressive therapy, and supportive care are discussed in detail. The aim is to provide the clinician with a better understanding of the disease and to offer guidelines for the management of children with this uncommon yet serious disorder.

  5. Acquired anhidrosis a case report

    Nair Laxmi

    1992-01-01

    Full Text Available A 30-year -old man was seen for acquired anhidrosis. There was no systemic disease. Vasomotor functions were normal. Biopsy showed normal sweat glands and ducts. Intravenous injection of neostigmine could produce profuse sweating on the face, trunk and arms. The disorder is likely to be due to a peripheral dysautonomia selectively affecting the sudomotor function.

  6. Acquired anhidrosis a case report

    Nair Laxmi; Beena D; Manohar S

    1992-01-01

    A 30-year -old man was seen for acquired anhidrosis. There was no systemic disease. Vasomotor functions were normal. Biopsy showed normal sweat glands and ducts. Intravenous injection of neostigmine could produce profuse sweating on the face, trunk and arms. The disorder is likely to be due to a peripheral dysautonomia selectively affecting the sudomotor function.

  7. The heat response of hydrocortisone receptors

    The sensitivity of hydrocortisone (HC) receptors to heat damage has been measured in Chinese hamster ovary (CHO) cells. The impetus for the study came from three observations: A. Hormone receptors (e.g. insulin) are very heat sensitizer and may be a primary target for heat damage (BBA 756, 1 (1983)). B. HC induces a receptor-mediated heat resistance in CHO cells (J. Cell. Physiol. 128, 127 (1986)). C. The HC receptor is a soluble protein complex, which, in its unactivated state, contains HSP 89 (EMBO J. 4, 3131 (1985); JBC 260 12398 (1985)). Upon binding of the ligand, HSP 89 dissociates and the activated receptor enters the nucleus and binds DNA. The current study reveals that the HC receptor is also very heat sensitive, losing 50% of its activity after 5 min at 450C, 10 min at 440C or 20 min at 430C. Receptor activity recovers quickly after heat, returning to levels close to normal within 2-4 hours after a treatment of 10 min at 450C which initially reduces receptor activity to less than 20% of control. Pretreatment with HC, using conditions that induce heat resistance, depresses receptor activity to 10-20% of control, but residual receptors display a heat sensitivity similar to that of control cells. So far, the authors have been unable to demonstrate any heat protection of HC receptors in thermotolerant cells

  8. Design and optimization of ethanol production from bagasse pith hydrolysate by a thermotolerant yeast Kluyveromyces sp. IIPE453 using response surface methodology

    Dasgupta, Diptarka; Suman, Sunil Kumar; Pandey, Diwakar; Ghosh, Debashish; Khan, Rashmi; Agrawal, Deepti; Jain, Rakesh Kumar; Vadde, Vasanta Thakur; Adhikari, Dilip K

    2013-01-01

    Ethanol production from sugarcane bagasse pith hydrolysate by thermotolerant yeast Kluyveromyces sp. IIPE453 was analyzed using response surface methodology. Variables such as Substrate Concentration, pH, fermentation time and Na2HPO4 concentration were found to influence ethanol production significantly. In a batch fermentation, optimization of key process variables resulted in maximum ethanol concentration of 17.44 g/L which was 88% of the theoretical with specific productivity of 0.36 g/L/h.

  9. Engineering of xylose reductase and overexpression of xylitol dehydrogenase and xylulokinase improves xylose alcoholic fermentation in the thermotolerant yeast Hansenula polymorpha

    Voronovsky Andriy Y; Abbas Charles A; Dmytruk Kostyantyn V; Dmytruk Olena V; Sibirny Andriy A

    2008-01-01

    Abstract Background The thermotolerant methylotrophic yeast Hansenula polymorpha is capable of alcoholic fermentation of xylose at elevated temperatures (45 – 48°C). Such property of this yeast defines it as a good candidate for the development of an efficient process for simultaneous saccharification and fermentation. However, to be economically viable, the main characteristics of xylose fermentation of H. polymorpha have to be improved. Results Site-specific mutagenesis of H. polymorpha XYL...

  10. Data for rapid ethanol production at elevated temperatures by engineered thermotolerant Kluyveromyces marxianus via the NADP(H)-preferring xylose reductase–xylitol dehydrogenase pathway

    Biao Zhang; Jia Zhang; Dongmei Wang; Xiaolian Gao; Lianhong Sun; Jiong Hong

    2015-01-01

    A thermo-tolerant NADP(H)-preferring xylose pathway was constructed in Kluyveromyces marxianus for ethanol production with xylose at elevated temperatures (Zhang et al., 2015 [25]). Ethanol production yield and efficiency was enhanced by pathway engineering in the engineered strains. The constructed strain, YZJ088, has the ability to co-ferment glucose and xylose for ethanol and xylitol production, which is a critical step toward enabling economic biofuel production from lignocellulosic bioma...

  11. Metabolic engineering to understand and control productionof l-glutamate from methanol by the methylotrophic thermotolerant bacterium Bacillus methanolicus

    Krog, Anne

    2013-01-01

    The production of L-glutamate and L-lysine together excides 3.5 million tons annually and are the most important amino acids in production volume. Their production is based on fermentation processes with the bacterium Corynebacterium glutamicum utilizing sugar as carbon and energy source. The thermotolerant methylotroph bacterium Bacillus methanolicus is a candidate for amino acid production from methanol at 50 ºC, using an alternative carbon source.In this work, the genome sequences of the t...

  12. Salicylic acid and heat acclimation pretreatment protects Laminaria japonica sporophyte (Phaeophyceae) from heat stress

    Zhou, Bin; Tang, Xuexi; Wang, You

    2010-07-01

    Possible mediatory roles of heat acclimation and salicylic acid in protecting the sporophyte of marine macroalga Laminaria japonica (Phaeophyceae) from heat stress were studied. Heat stress resulted in oxidative injury in the kelp blades. Under heat stress significant accumulation of hydrogen peroxide (H2O2) and malonaldehyde (MDA), a membrane lipid peroxidation product, and a drastic decrease in chlorophyll a content were recorded. Activity of the enzymatic antioxidant system was drastically affected by heat stress. The activity of superoxide dismutase (SOD) was significantly increased while peroxidase (POD), catalase (CAT) and glutathione peroxidase (GPX) were greatly inhibited and, simultaneously, phenylalanine ammonia-lyase was activated while polyphenol oxidase (PPO) was inhibited. Both heat acclimation pretreatment and exogenous application of salicylic acid alleviated oxidative damage in kelp blades. Blades receiving heat acclimation pretreatment and exogenous salicylic acid prior to heat stress exhibited a reduced increase in H2O2 and MDA content, and a lower reduction in chlorophyll a content. Pretreatment with heat acclimation and salicylic acid elevated activities of SOD, POD, CAT, GPX and PPO. Considering these results collectively, we speculate that the inhibition of antioxidant enzymes is a possible cause of the heat-stress-induced oxidative stress in L. japonica, and enhanced thermotolerance may be associated, at least in part, with the elevated activity of the enzymatic antioxidant system.

  13. CNOOC Acquires Oversea Assets Successfully

    Hu Senlin

    2006-01-01

    @@ After last year CNOOC's bidding for buy the US energy company Unocal Corp lost out to the Chevron Corporation, it conducted the crossing-border asset-acquirement again in the beginning of this year. On Jan. 9, 2006,CNOOC Ltd signed a definitive agreement with Nigeria South Atlantic Petroleum Limited (SAPETRO) to acquire a 45 % working interest in an offshore oil developing license OML 130 in Nigeria for US$2.268 billion cash. The purchase will be funded by the internal capital resources of CNOOC Ltd. In which, US$1.75 billion will pay for buying SAPETRO, and the remaining cash will be used to pay for the early operation cost.

  14. Occupationally Acquired American Cutaneous Leishmaniasis

    Maria Edileuza Felinto de Brito

    2012-01-01

    Full Text Available We report two occupationally acquired cases of American cutaneous leishmaniasis (ACL: one accidental laboratory autoinoculation by contaminated needlestick while handling an ACL lesion sample, and one acquired during field studies on bird biology. Polymerase chain reaction (PCR assays of patient lesions were positive for Leishmania, subgenus Viannia. One isolate was obtained by culture (from patient 2 biopsy samples and characterized as Leishmania (Viannia naiffi through an indirect immunofluorescence assay (IFA with species-specific monoclonal antibodies (mAbs and by multilocus enzyme electrophoresis (MLEE. Patients were successfully treated with N-methyl-glucamine. These two cases highlight the potential risks of laboratory and field work and the need to comply with strict biosafety procedures in daily routines. The swab collection method, coupled with PCR detection, has greatly improved ACL laboratory diagnosis.

  15. Cogema acquires TOTAL's uranium assets

    On April 28, France's nuclear fuel cycle conglomerate Cogema and petroleum group TOTAL announced a plan in which Cogema will assume ownership of TOTAL's uranium assets worldwide, and as part of the deal, each firm will acquire shares of the other. On June 2, the agreement will be submitted to shareholders and, assuming it is approved, will go into effect this year. The agreement calls for TOTAL to acquire a 10.8-percent share in Cogema, thus becoming its first private sector shareholder, by underwriting a reserve capital increase of FF1.5 billion (approximately US$283 million). In return, Cogema will pay FF2.52 billion for approximately 4.3 percent of TOTAL, as part of a reserve capital increase totalling FF4.07 billion

  16. Acquired causes of intestinal malabsorption.

    van der Heide, F

    2016-04-01

    This review focuses on the acquired causes, diagnosis, and treatment of intestinal malabsorption. Intestinal absorption is a complex process that depends on many variables, including the digestion of nutrients within the intestinal lumen, the absorptive surface of the small intestine, the membrane transport systems, and the epithelial absorptive enzymes. Acquired causes of malabsorption are classified by focussing on the three phases of digestion and absorption: 1) luminal/digestive phase, 2) mucosal/absorptive phase, and 3) transport phase. Most acquired diseases affect the luminal/digestive phase. These include short bowel syndrome, extensive small bowel inflammation, motility disorders, and deficiencies of digestive enzymes or bile salts. Diagnosis depends on symptoms, physical examination, and blood and stool tests. There is no gold standard for the diagnosis of malabsorption. Further testing should be based on the specific clinical context and the suspected underlying disease. Therapy is directed at nutritional support by enteral or parenteral feeding and screening for and supplementation of deficiencies in vitamins and minerals. Early enteral feeding is important for intestinal adaptation in short bowel syndrome. Medicinal treatment options for diarrhoea in malabsorption include loperamide, codeine, cholestyramine, or antibiotics. PMID:27086886

  17. Inhibitors against the coagulation factors spontaneously acquired: Acquired B Hemophilia

    Claudia Lucía Sossa Melo; Sara Inés Jiménez Sanguino; Pilar Rodríguez

    2003-01-01

    Spontaneously acquired inhibitors to factor IX, are extremely rare. A 70-year-old male, presented with major continuous post-orthopedic surgery bleeding. His initial APTT was 77.4 s (normal range, 25-36) and normal PT. Expanded APTT corrects, results in favor of deficit of factor IX, confirming the level of dose of IX factor: 52% (NR 70–125%) with normal factor VIII. It was realized with fresh frozen plasma, and by the fifth day of treatment, he presents a bruise in the surgery bed with radic...

  18. Heat damage to DNA polymerases as a possible cause for hyperthermic cell killing and radiosensitization by heat

    Reports in the literature suggest a causal relationship between heat effects on the activity of DNA polymerase β and hyperthermic cell killing. By using thermotolerance as a tool to investigate this possibility it was found that a poor correlation existed between these two parameters, but a good correlation was observed between the decrease in activity of this enzyme and the extent of radiosensitization by heat. To further pursue the role of DNA polymerases in the mechanism of cell killing, step-down heating procedures were introduced. No sensitization of polymerase inactivation was observed with this treatment. From the results of the experiments reported, the authors like to conclude that heat inactivation of DNA polymerase β is not to be considered as the general cause of hypethermic death

  19. Thermotolerance of Leaf Discs from Four Isoprene-Emitting Species Is Not Enhanced by Exposure to Exogenous Isoprene1

    Logan, Barry A.; Monson, Russell K.

    1999-01-01

    The effects of exogenously supplied isoprene on chlorophyll fluorescence characteristics were examined in leaf discs of four isoprene-emitting plant species, kudzu (Pueraria lobata [Willd.] Ohwi.), velvet bean (Mucuna sp.), quaking aspen (Populus tremuloides Michx.), and pussy willow (Salix discolor Muhl). Isoprene, supplied to the leaves at either 18 μL L−1 in compressed air or 21 μL L−1 in N2, had no effect on the temperature at which minimal fluorescence exhibited an upward inflection during controlled increases in leaf-disc temperature. During exposure to 1008 μmol photons m−2 s−1 in an N2 atmosphere, 21 μL L−1 isoprene had no effect on the thermally induced inflection of steady-state fluorescence. The maximum quantum efficiency of photosystem II photochemistry decreased sharply as leaf-disc temperature was increased; however, this decrease was unaffected by exposure of leaf discs to 21 μL L−1 isoprene. Therefore, there were no discernible effects of isoprene on the occurrence of symptoms of high-temperature damage to thylakoid membranes. Our data do not support the hypothesis that isoprene enhances leaf thermotolerance. PMID:10398717

  20. Thermotolerance of leaf discs from four isoprene-emitting species is not enhanced by exposure to exogenous isoprene

    Logan; Monson

    1999-07-01

    The effects of exogenously supplied isoprene on chlorophyll fluorescence characteristics were examined in leaf discs of four isoprene-emitting plant species, kudzu (Pueraria lobata [Willd.] Ohwi.), velvet bean (Mucuna sp.), quaking aspen (Populus tremuloides Michx.), and pussy willow (Salix discolor Muhl). Isoprene, supplied to the leaves at either 18 &mgr;L L-1 in compressed air or 21 &mgr;L L-1 in N2, had no effect on the temperature at which minimal fluorescence exhibited an upward inflection during controlled increases in leaf-disc temperature. During exposure to 1008 &mgr;mol photons m-2 s-1 in an N2 atmosphere, 21 &mgr;L L-1 isoprene had no effect on the thermally induced inflection of steady-state fluorescence. The maximum quantum efficiency of photosystem II photochemistry decreased sharply as leaf-disc temperature was increased; however, this decrease was unaffected by exposure of leaf discs to 21 &mgr;L L-1 isoprene. Therefore, there were no discernible effects of isoprene on the occurrence of symptoms of high-temperature damage to thylakoid membranes. Our data do not support the hypothesis that isoprene enhances leaf thermotolerance. PMID:10398717

  1. A strategy for soluble overexpression and biochemical characterization of halo-thermotolerant Bacillus laccase in modified E. coli.

    Safary, Azam; Moniri, Rezvan; Hamzeh-Mivehroud, Maryam; Dastmalchi, Siavoush

    2016-06-10

    An efficient method was introduced for soluble expression of recombinant laccase (rpCotA(SL-1)) from a newly isolated halo-thermotolerant Bacillus sp. SL-1 in modified Escherichia coli, trxB2/gor2 mutant (Origami™ B (DE3)). The yield of purified soluble laccase in Origami strain under micro-aerobic condition was ∼20mg/L of bacterial culture, showing significant improvement over the laccase produced in E.coli BL21 strain under aerobic condition. The specific activity of 13U/mg for purified laccase produced in micro-aerobic condition was higher than that of 1.07U/mg observed for the purified enzyme obtained in aerobic condition in Origami. The kinetic Km and kcat parameters for laccase-induced oxidation reactions were 46μM and 23s(-1) for ABTS (2,2'-Azino-bis(3-ethylbenzthiazoline-6-sulphonic acid), and 19.6μM and 24s(-1) for SGZ (syringaldazine) substrates, respectively. The rpCotA(SL-1) displayed thermostability at 70°C and tolerance to specified concentrations of NaCl, NaN3, EDTA and SDS as inhibitors. The enzyme was relatively stable in the presence of different concentration of organic solvents, however the residual activity was adversely affected as the dipole moment of the solvents increase. Here we successfully report the production of soluble and functional laccase in Origami at the expression level suitable for industrial application. PMID:27059481

  2. Number of residual thermotolerant coliforms on plants and in soil when using reclaimed domestic wastewater for irrigation.

    Khamkure, Sasirot; Cervantes, Edmundo Peña; Zermeño González, Alejandro; Cervantes, Rubén López; Melo, Prócoro Gamero; Ramírez, Homero

    2013-01-01

    The reclamation of domestic wastewater for irrigation is one alternative approach to solve the water scarcity crisis, but it is essential to control the microbiological quality of wastewater used for irrigation. The removal of thermotolerant coliforms, also known as faecal coliforms (FC), from treated domestic wastewater by intermittent media infiltration (IMI) in column was studied. The columns were filled with natural filter media (soil, soil/charcoal and zinc-modified zeolite, Zeo-Zn), and wastewater, IMI-treated wastewater and disinfected wastewater were compared. The numbers of residual FC on Swiss chard (Beta vulgaris) and in agricultural soil were determined over a 4-month period. The column using Zeo-Zn had a higher FC removal efficiency (2.98 log) than columns with other filter media and disinfection (1.87-2.57 log) due to the bactericidal properties of Zn(2+). The treatment of wastewater using Zeo-Zn and disinfection both decreased the accumulation of FC on plants and in soil to approximately 1-20 MPN/g dry matter. IMI-treated wastewater using the column with Zeo-Zn was suitable for unrestricted agricultural use, complied with Mexican regulations (as did disinfected wastewater) and had a low risk of FC contamination of plants and soil. PMID:23168639

  3. Knowledge transfer - Acquiring implicit knowledge

    Many organisations have recognised the problem of experts taking home a huge amount of specific knowledge, which they have gathered in their department, when they leave. The successor is capable only of acquiring explicit expertise because implicit experiences are not documented and therefore no more available. That is why we have started this pilot study in order to try to conserve the above mentioned tacit and implicit knowledge and to make it available to other colleagues. Using a semi-standardised interview we elicit tacit knowledge from the expert and summarise it in a report. This interview-guideline forms the basis of in-depth investigation for implicit knowledge. (author)

  4. Complement's participation in acquired immunity

    Nielsen, Claus Henrik; Leslie, Robert Graham Quinton

    2002-01-01

    B cell receptor for antigen (BCR), a complex composed of the iC3b/C3d fragment-binding complement type 2 receptor (CR2, CD21) and its signaling element CD19 and the IgG-binding receptor FcgammaRIIb (CD32). The positive or negative outcome of signaling through this triad is determined by the context...... in which antigen is seen, be it alone or in association with natural or induced antibodies and/or C3-complement fragments. The aim of this review is to describe the present status of our understanding of complement's participation in acquired immunity and the regulation of autoimmune responses.......The preliminary evidence for the involvement of complement in promoting primary humoral responses dates back over a quarter of a century. However, it is only in the course of the past decade or so that the detailed mechanisms underlying complement's influence have been characterized in depth. It is...

  5. Pseudomona pseudomallei community acquired pneumonia

    This is the first published case report en Colombia about pseudomona pseudomallei community acquired pneumonia. This uncommon pathogen is from the epidemiological standpoint a very important one and medical community should be aware to look after it in those patients where no other etiological pathogen is recovered. A brief summary about epidemiology is showed, emphasizing those regions where it can be found. Likewise, comments about the differential diagnosis are important since it should be considered in those patients where tuberculosis is suspected. This is particularly representative for countries with high tuberculosis rates. Furthermore, a microbiological review is shown, emphasizing on isolation techniques, descriptions about therapeutics and other regarding treatment issues according international standards. Finally; a description about the clinical picture, laboratory findings, treatment and evolution of the case reported are shown for discussion

  6. Genetic and epigenetic control of plant heat responses

    Junzhong eLiu

    2015-04-01

    Full Text Available Plants have evolved sophisticated genetic and epigenetic regulatory systems to respond quickly to unfavorable environmental conditions such as heat, cold, drought, and pathogen infections. In particular, heat greatly affects plant growth and development, immunity and circadian rhythm, and poses a serious threat to the global food supply. According to temperatures exposing, heat can be usually classified as warm ambient temperature (about 22-27℃, high temperature (27-30℃ and extremely high temperature (37-42℃, also known as heat stress for the model plant Arabidopsis thaliana. The genetic mechanisms of plant responses to heat have been well studied, mainly focusing on elevated ambient temperature-mediated morphological acclimation and acceleration of flowering, modulation of plant immunity and circadian clock by high temperatures, and thermotolerance to heat stress. Recently, great progress has been achieved on epigenetic regulation of heat responses, including DNA methylation, histone modifications, histone variants, ATP-dependent chromatin remodeling, histone chaperones, small RNAs, long non-coding RNAs and other undefined epigenetic mechanisms. These epigenetic modifications regulate the expression of heat-responsive genes and function to prevent heat-related damage. This review focuses on recent progresses regarding the genetic and epigenetic control of heat responses in plants, and pays more attention to the role of the major epigenetic mechanisms in plant heat responses. Further research perspectives are also discussed.

  7. Acquired vulval lymphangiectases mimicking genital warts

    Sharma Rajeev; Tomar Sudarshan; Chandra Mithilesh

    2002-01-01

    Acquired lymphangiectasia can sometimes occur on the vulva and cause diagnostic difficulties especially if they have a warty appearance. We report a case of acquired vulva I lymphangiectasia which mimicked genital warts.

  8. Acquired vulval lymphangiectases mimicking genital warts

    Sharma Rajeev

    2002-01-01

    Full Text Available Acquired lymphangiectasia can sometimes occur on the vulva and cause diagnostic difficulties especially if they have a warty appearance. We report a case of acquired vulva I lymphangiectasia which mimicked genital warts.

  9. ADPase activity of recombinantly expressed thermotolerant ATPases may be caused by copurification of adenylate kinase of Escherichia coli

    Chen, Baoyu; Sysoeva, Tatyana A.; Chowdhury, Saikat; Guo, Liang; Nixon, B.Tracy; (IIT); (Penn)

    2009-10-06

    Except for apyrases, ATPases generally target only the {gamma}-phosphate of a nucleotide. Some non-apyrase ATPases from thermophilic microorganisms are reported to hydrolyze ADP as well as ATP, which has been described as a novel property of the ATPases from extreme thermophiles. Here, we describe an apparent ADP hydrolysis by highly purified preparations of the AAA+ ATPase NtrC1 from an extremely thermophilic bacterium, Aquifex aeolicus. This activity is actually a combination of the activities of the ATPase and contaminating adenylate kinase (AK) from Escherichia coli, which is present at 1/10 000 of the level of the ATPase. AK catalyzes conversion of two molecules of ADP into AMP and ATP, the latter being a substrate for the ATPase. We raise concern that the observed thermotolerance of E. coli AK and its copurification with thermostable proteins by commonly used methods may confound studies of enzymes that specifically catalyze hydrolysis of nucleoside diphosphates or triphosphates. For example, contamination with E. coli AK may be responsible for reported ADPase activities of the ATPase chaperonins from Pyrococcus furiosus, Pyrococcus horikoshii, Methanococcus jannaschii and Thermoplasma acidophilum; the ATP/ADP-dependent DNA ligases from Aeropyrum pernix K1 and Staphylothermus marinus; or the reported ATP-dependent activities of ADP-dependent phosphofructokinase of P. furiosus. Purification methods developed to separate NtrC1 ATPase from AK also revealed two distinct forms of the ATPase. One is tightly bound to ADP or GDP and able to bind to Q but not S ion exchange matrixes. The other is nucleotide-free and binds to both Q and S ion exchange matrixes.

  10. Infections Acquired in the Garden.

    Cunha, Cheston B; Cunha, Burke A

    2015-10-01

    Gardening is a wonderful pastime, and the garden is a very peaceful place to enjoy one's vacation. However, the garden may be a treacherous place for very young or compromised hosts when one takes into account the infectious potential residing in the soil, as well as the insect vectors on plants and animals. Even normal hosts may acquire a variety of infections from the soil, animals, or animal-related insect bites. The location of the garden, its natural animal and insect inhabitants, and the characteristics of the soil play a part in determining its infectious potential. The most important factor making the garden an infectious and dangerous place is the number and interaction of animals, whether they are pets or wild, that temporarily use the garden for part of their daily activities. The clinician should always ask about garden exposure, which will help in eliminating the diagnostic possibilities for the patient. The diagnostic approach is to use epidemiological principles in concert with clinical clues, which together should suggest a reasonable list of diagnostic possibilities. Organ involvement and specific laboratory tests help further narrow the differential diagnosis and determine the specific tests necessary to make a definitive diagnosis. PMID:26542044

  11. Isolation of thermotolerant Vermamoeba vermiformis strains from water sources in Lanzarote Island, Canary Islands, Spain.

    Reyes-Batlle, María; Wagner, Carolina; Zamora-Herrera, Jonadab; Vargas-Mesa, Alejandro; Sifaoui, Ines; González, Ana C; López-Arencibia, Atteneri; Valladares, Basilio; Martínez-Carretero, Enrique; Piñero, José E; Lorenzo-Morales, Jacob

    2016-09-01

    In this study, twenty water samples were collected in the island of Lanzarote, Canary Islands, Spain in order to check for the presence of V. vermiformis strains in these samples. Water samples were cultured on 2% Non-Nutrient Agar (NNA) plates covered with a thin layer of heat killed E. coli and checked daily for the presence of Vermamoeba. After a week, V. vermiformis amoebae were observed in 2 of the 20 processed samples (10%) incubated at room temperature and 37°C. Molecular characterization was carried out by amplifying the 18S rDNA gene and DNA sequencing in order to confirm the identity of the isolated amoebic strains. To the best of our knowledge, this is the first report on the presence of FLA in environmental sources in Lanzarote Island and the first report of Vermamoeba vermiformis in water sources in this island. Furthermore, the two strains isolated in this study were collected in recreational areas with close contact with humans and thus awareness should be raised. PMID:27447234

  12. Surface Sampler Arm Acquiring Sample

    1976-01-01

    Operation of the surface sampler in obtaining Martian soil for Viking 2's molecular analysis experiment last Saturday (September 25) was closely monitored by one of the Lander cameras because of the precision required in trenching the small area--8 by 9 inches-surrounded by rocks. Dubbed 'Bonneville Salt Flats,' the exposure of thin crust appeared unique in contrast with surrounding materials and became a prime target for organic analysis in spite of potential hazards. Large rock in foreground is 8 inches high. At left, the sampler scoop has touched the surface, missing the rock at upper left by a comfortable 6 inches, and the backhoe has penetrated the surface about one-half inch. The scoop was then pulled back to sample the desired point and (second photo) the backhoe furrowed the surface pulling a piece of thin crust toward the spacecraft. The initial touchdown and retraction sequence was used to avoid a collision between a rock in the shadow of the arm and a plate joining the arm and scoop. The rock was cleared by 2 to 3 inches. The third picture was taken 8 minutes after the scoop touched the surface and shows that the collector head has acquired a quantity of soil. With surface sampler withdrawn (right), the foot-long trench is seen between the rocks. The trench is three inches wide and about 1 1/2 to 2 inches deep. The scoop reached to within 3 inches of the rock at far end of trench. Penetration appears to have left a cavernous opening roofed by the crust and only about one inch of undisturbed crust separates the deformed surface and the rock.

  13. Lipase production from a novel thermo-tolerant and extreme acidophile Bacillus pumilus using palm oil as the substrate and treatment of palm oil-containing wastewater.

    Saranya, P; Sukanya Kumari, H; Prasad Rao, B; Sekaran, G

    2014-03-01

    The thermo-tolerant and extreme acidophilic microorganism Bacillus pumilus was isolated from the soil collected from a commercial edible-oil extraction industry. Optimisation of conditions for the lipase production was conducted using response surface methodology. The optimum conditions for obtaining the maximum activity (1,100 U/mL) of extremely acidic thermostable lipase were fermentation time, 96 h; pH, 1; temperature, 50 °C; and concentration of palm oil, 50 g/L. After purification, a 7.1-fold purity of lipase with specific activity of 5,173 U/mg protein was obtained. The molecular weight of the thermo-tolerant acidophilic lipase (TAL) was 55 kDa. The predominant amino acid in the TAL was glycine. The functional groups of lipase were determined by Fourier transform infrared spectroscopy. TAL exhibited enhanced activity (114 %) with dimethyl sulphoxide (20 %, v/v), and it showed a moderate activity with methanol, hexane and benzene. The optimum conditions for the treatment of palm oil in wastewater using the TAL were found to be time, 3 h; pH, 1; temperature, 50 °C with pseudo second-order kinetic constant of 1.88 × 10(-3) L mol(-1) min(-1). The Michaelis-Menten enzyme kinetic model and the nonlinear kinetic model were evaluated for the TAL. TAL established hydrolysis efficiency of 96 % for palm oil in wastewater at 50 °C. PMID:24293300

  14. 17 CFR 210.8-06 - Real estate operations acquired or to be acquired.

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Real estate operations acquired or to be acquired. 210.8-06 Section 210.8-06 Commodity and Securities Exchanges SECURITIES AND... Statements of Smaller Reporting Companies § 210.8-06 Real estate operations acquired or to be acquired....

  15. An efficient thermotolerant and halophilic biosurfactant-producing bacterium isolated from Dagang oil field for MEOR application

    Wu, Langping; Richnow, Hans; Yao, Jun; Jain, Anil

    2014-05-01

    Dagang Oil field (Petro China Company Limited) is one of the most productive oil fields in China. In this study, 34 biosurfactant-producing strains were isolated and cultured from petroleum reservoir of Dagang oil field, using haemolytic assay and the qualitative oil-displacement test. On the basis of 16S rDNA analysis, the isolates were closely related to the species in genus Pseudomonas, Staphylococcus and Bacillus. One of the isolates identified as Bacillus subtilis BS2 were selected for further study. This bacterium was able to produce a type of biosurfactant with excessive foam-forming properties at 37ºC as well as at higher temperature of 55ºC. The biosurfactant produced by the strain BS2 could reduce the surface tension of the culture broth from 70.87 mN/m to 28.97 mN/m after 8 days of incubation at 37ºC and to 36.15 mN/m after 20 days of incubation at 55ºC, respectively. The biosurfactant showed stability at high temperature (up to 120ºC), a wide range of pH (2 to 12) and salt concentrations (up to 12%) offering potential for biotechnology. Fourier transform infrared (FT-IR) spectrum of extracted biosurfactant tentatively characterized the produced biosurfactant as glycolipid derivative. Elemental analysis of the biosurfactant by energy dispersive X-ray spectroscopy (EDS) reveals that the biosurfactant was anionic in nature. 15 days of biodegradation of crude oil suggested a preferential usage of n-alkane upon microbial metabolism of BS2 as a carbon substrate and consequently also for the synthesis of biosurfactants. Core flood studies for oil release indicated 9.6% of additional oil recovery over water flooding at 37ºC and 7.2% of additional oil recovery at 55 ºC. Strain BS2 was characterized as an efficient biosurfactant-producing, thermotolerant and halophillic bacterium and has the potential for application for microbial enhanced oil recovery (MEOR) through water flooding in China's oil fields even in situ as adapted to reservoir chemistry and

  16. Adult Heat Tolerance Variation in Drosophila melanogaster is Not Related to Hsp70 Expression

    Jensen, Louise Toft; Cockerell, Fiona Elizabeth; Kristensen, Torsten Nygaard; Rako, Lea; Loeschcke, Volker; McKechnie, Stephen William; Hoffmann, Ary

    Expression of heat-inducible Hsp70 is considered closely linked to thermotolerance in Drosophila melanogaster and other ectotherms. However, intra-specific variation of Hsp70 expression levels and its relationship to heat resistance has only been investigated in a few studies. Although in...... Drosophila larvae Hsp70 expression may be a key determinant of heat tolerance, the evidence for this in adults is equivocal. We therefore examined heat-induced Hsp70 expression and several measurements of adult heat tolerance in three independent collections of D. melanogaster, measured in three laboratories...... correlation between Hsp70 expression and laboratory assays of adult heat tolerance commonly used in Drosophila. When combining data across three studies we had high power to detect associations but the results showed that variation in Hsp70 expression is only likely to explain a small proportion of variation...

  17. Intelligent Microbial Heat-Regulating Engine (IMHeRE) for Improved Thermo-Robustness and Efficiency of Bioconversion.

    Jia, Haiyang; Sun, Xiangying; Sun, Huan; Li, Chenyi; Wang, Yunqian; Feng, Xudong; Li, Chun

    2016-04-15

    The growth and production of microorganisms in bioconversion are often hampered by heat stress. In this study, an intelligent microbial heat-regulating engine (IMHeRE) was developed and customized to improve the thermo-robustness of Escherichia coli via the integration of a thermotolerant system and a quorum-regulating system. At the cell level, the thermotolerant system composed of different heat shock proteins and RNA thermometers hierarchically expands the optimum temperature by sensing heat changes. At the community level, the quorum-regulating system dynamically programs the altruistic sacrifice of individuals to reduce metabolic heat release by sensing the temperature and cell density. Using this hierarchical, dynamical, and multilevel regulation, the IMHeRE is able to significantly improve cell growth and production. In a real application, the production of lysine was increased 5-fold at 40 °C using the IMHeRE. Our work provides new potential for the development of bioconversion by conserving energy and increasing productivity. PMID:26793993

  18. Acquired intrathoracic kidney in thoracic kyphosis

    Two cases of acquired intrathoracic kidney associated with thoracic kyphosis are reported, with emphasis on the radiographic manifestations. A search of the scientific literature disclosed that the acquired type of this abnormality is rare. The importance of recognizing this entity from a differential diagnostic standpoint is underscored. (author)

  19. Acquired Zinc Deficiency in an Adult Female

    Mohanan Saritha; Divya Gupta; Laxmisha Chandrashekar; Devinder M Thappa; Nachiappa G Rajesh

    2012-01-01

    Acrodermatitis enteropathica is an autosomal recessive inherited disorder of zinc absorption. Acquired cases are reported occasionally in patients with eating disorders or Crohn′s disease. We report a 24-year-old housewife with acquired isolated severe zinc deficiency with no other comorbidities to highlight the rare occurrence of isolated nutritional zinc deficiency in an otherwise normal patient.

  20. And the Winner is – Acquired

    Henkel, Joachim; Rønde, Thomas; Wagner, Marcus

    value in case of success—that is, a more radical innovation. In the second stage, successful entrants bid to be acquired by the incumbent. We assume that entrants cannot survive on their own, so being acquired amounts to a ‘prize’ in a contest. We identify an equilibrium in which the incumbent chooses...

  1. Enrichment followed by quantitative PCR both for rapid detection and as a tool for quantitative risk assessment of food-borne thermotolerant campylobacters

    Josefsen, Mathilde Hartmann; Jacobsen, N. R.; Hoorfar, Jeffrey

    2004-01-01

    As part of a large international project for standardization of PCR (Food-PCR; www.pcr.dk), a multiplex, multiplatform, ready-to-go enrichment followed by a real-time PCR method, including an internal amplification control, was developed for detection of food-borne thermotolerant campylobacters in...... Organization (ISO)-based culture method by testing low, medium, and high levels of 12 spiked and 66 unspiked, presumably naturally contaminated, chicken rinse samples. In the RotorGene, a positive PCR response was detected in 40 samples of the 66. This was in complete agreement with the enriched ISO culture...... naturally contaminated chicken samples, which indicates PCR's additional potential as a tool for quantitative risk assessment. Signal from the internal amplification control was detected in all culture-negative samples (VIC Ct: 23.1 to 28.1). The method will be taken further and validated in an...

  2. Evaluation of thermotolerant capacity of lactic acid bacteria isolated from commercial sausages and the effects of their addition on the quality of cooked sausages Avaliação da capacidade termotolerante de bacterias lácticas isoladas de salsichas comerciais e os efeitos de sua adição na qualidade de salsichas cozidas

    María de Lourdes Pérez-Chabela; Alfonso Totosaus; Isabel Guerrero

    2008-01-01

    The thermotolerant capacity of several lactic acid bacteria strains isolated from cooked commercial sausages was determined. Four strains were positively identified as Lactobacillus plantarum, Lactobacillus curvatus, Pediococcus pentosaceus and Pediococcus acidilacti, after surviving thermal treatment (70 °C during 60 minutes). Thermotolerant strains were inoculated in sausage batters before cooking in order to determine their effect on color, texture, acceptance and inhibition of Enterob...

  3. Enhancing Medicares Hospital Acquired Conditions Policy

    U.S. Department of Health & Human Services — The current Medicare policy of non-payment to hospitals for Hospital Acquired Conditions (HAC) seeks to avoid payment for preventable complications identified...

  4. Acquired Inventors’ Productivity after Horizontal Acquisition

    Colombo, Massimo G.; Moreira, Solon; Rabbiosi, Larissa

    Effective integration of the R&D functions of the acquired and acquiring firms is essential for knowledge recombination after acquisition. However, prior research suggests that the post-acquisition integration process often damages the inventive labor force. We argue that an examination of the mu......Effective integration of the R&D functions of the acquired and acquiring firms is essential for knowledge recombination after acquisition. However, prior research suggests that the post-acquisition integration process often damages the inventive labor force. We argue that an examination...... of the multifaceted nature of the integration process further enhances our understanding of which conditions will be more or less detrimental for corporate inventors. We focus on R&D teams which are the immediate organizational context in which inventors operate and drawing on insights from learning theory...

  5. Hospital-Acquired Condition Reduction Program

    U.S. Department of Health & Human Services — In October 2014, CMS began reducing Medicare payments for subsection (d) hospitals that rank in the worst performing quartile with respect to hospital-acquired...

  6. Infections acquired in clinical laboratories in Utah.

    Jacobson, J.T.; Orlob, R B; Clayton, J L

    1985-01-01

    We reviewed laboratory-acquired infections occurring in Utah from 1978 through 1982. Written and telephone interviews of supervisors of 1,191 laboratorians revealed an estimated annual incidence of 3 laboratory-acquired infections per 1,000 employees. Infections, in order of frequency, included hepatitis B (clinical cases), shigellosis, pharyngitis, cellulitis, tuberculosis (skin test conversion), conjunctivitis, and non-A, non-B hepatitis. One-half of large laboratories (over 25 employees), ...

  7. The Acquired Immunodeficiency Syndrome: current status.

    Quagliarello, V.

    1982-01-01

    A recently recognized syndrome of acquired immunodeficiency (Acquired Immunodeficiency Syndrome-AIDS) has arisen since June 1981. It has received international attention. The clinical spectrum consists of repeated opportunistic infections, rare malignancies, and autoimmune phenomena, occurring in previously healthy adults with no history of an immunologic disorder. The population subset at risk for this syndrome appears to be predominantly homosexual American males and intravenous drug abuser...

  8. Characterization and radiation response of a heat-resistant variant of V79 cells

    A thermoresistant variant of the established cell line V79-S171-W1 was isolated after treatment with nitrosoguanidine and repeated heat treatments at 42.6 to 43 degrees C, and showed an enhanced ability to survive at 42.6, 43.5, and 44.5 degrees C. The rates of inactivation of the normal and heat-resistant lines differed by approximately a factor of 2 over this temperature range. This level of thermoresistance was stable for the first 80 doublings, but was lost by 120 doublings. This may have been due to a reversion to the normal V79 line since there was no continuous selection pressure and the thermoresistant variant, which was designated at HR7, had a longer average doubling time. Transient thermotolerance was induced in both the V79 and HR7 cells by a 10-min exposure to 44.5 degrees C. After 3 hr incubation at 37 degrees C, both cell lines had an identical sensitivity to further exposure to 44.5 degrees C. Thus the long-term thermoresistance of the HR7 cells may be due to a permanent induction of a low level of thermotolerance. The (ionizing) radiation survival curves and the ability to repair sublethal radiation damage were identical for the thermoresistant variant and the parent cell line

  9. Characterization and radiation response of a heat-resistant variant of V79 cells

    A thermoresistant variant of the established cell line V79-S171-W1 was isolated after treatment with nitrosoguanidine and repeated heat treatments at 42.6 to 430C, and showed an enhanced ability to survive at 42.6, 43.5, and44.50C. The rates of inactivation of the normal and heat-resistant lines differed by approximately a factor of 2 over this temperature range. This level of thermoresistance was stable for the first 80 doublings, but was lost by 120 doublings. This may have been due to a reversion to the normal V79 line since there was no continuous selection pressure and the thermoresistant variant, which was designated at HR7, had a longer average doubling time. Transient thermotolerance was induced in both the V79 and HR7 cells by a 10-min expsure to 44.50C. After 3 hr incubation at 370C, both cell lines had an identical sensitivity to further exposure to 44.50C. Thus the long-term thermoresistance of the HR7 cells may be due to a permanent induction of a low level of thermotolerance. The (ionizing) radiation survival curves and the ability to repair sublethal radiation damage were identical for the thermoresistance variant and the parent cell line

  10. Transcriptomic analysis of grape (Vitis vinifera L. leaves during and after recovery from heat stress

    Liu Guo-Tian

    2012-09-01

    Full Text Available Abstract Background Grapes are a major fruit crop around the world. Heat stress can significantly reduce grape yield and quality. Changes at the molecular level in response to heat stress and subsequent recovery are poorly understood. To elucidate the effect of heat stress and subsequent recovery on expression of genes by grape leaves representing the classic heat stress response and thermotolerance mechanisms, transcript abundance of grape (Vitis vinifera L. leaves was quantified using the Affymetrix Grape Genome oligonucleotide microarray (15,700 transcripts, followed by quantitative Real-Time PCR validation for some transcript profiles. Results We found that about 8% of the total probe sets were responsive to heat stress and/or to subsequent recovery in grape leaves. The heat stress and recovery responses were characterized by different transcriptional changes. The number of heat stress-regulated genes was almost twice the number of recovery-regulated genes. The responsive genes identified in this study belong to a large number of important traits and biological pathways, including cell rescue (i.e., antioxidant enzymes, protein fate (i.e., HSPs, primary and secondary metabolism, transcription factors, signal transduction, and development. We have identified some common genes and heat shock factors (HSFs that were modulated differentially by heat stress and recovery. Most HSP genes were upregulated by heat stress but were downregulated by the recovery. On the other hand, some specific HSP genes or HSFs were uniquely responsive to heat stress or recovery. Conclusion The effect of heat stress and recovery on grape appears to be associated with multiple processes and mechanisms including stress-related genes, transcription factors, and metabolism. Heat stress and recovery elicited common up- or downregulated genes as well as unique sets of responsive genes. Moreover, some genes were regulated in opposite directions by heat stress and recovery

  11. Genetic variation in resistance of the preimplantation bovine embryo to heat shock.

    Hansen, Peter J

    2014-12-01

    Reproduction is among the physiological functions in mammals most susceptible to disruption by hyperthermia. Many of the effects of heat stress on function of the oocyte and embryo involve direct effects of elevated temperature (i.e. heat shock) on cellular function. Mammals limit the effects of heat shock by tightly regulating body temperature. This ability is genetically controlled: lines of domestic animals have been developed with superior ability to regulate body temperature during heat stress. Through experimentation in cattle, it is also evident that there is genetic variation in the resistance of cells to the deleterious effects of elevated temperature. Several breeds that were developed in hot climates, including Bos indicus (Brahman, Gir, Nelore and Sahiwal) and Bos taurus (Romosinuano and Senepol) are more resistant to the effects of elevated temperature on cellular function than breeds that evolved in cooler climates (Angus, Holstein and Jersey). Genetic differences are expressed in the preimplantation embryo by Day 4-5 of development (after embryonic genome activation). It is not clear whether genetic differences are expressed in cells in which transcription is repressed (oocytes >100 µm in diameter or embryos at stages before embryonic genome activation). The molecular basis for cellular thermotolerance has also not been established, although there is some suggestion for involvement of heat shock protein 90 and the insulin-like growth factor 1 system. Given the availability of genomic tools for genetic selection, identification of genes controlling cellular resistance to elevated temperature could be followed by progress in selection for those genes within the populations in which they exist. It could also be possible to introduce genes from thermotolerant breeds into thermally sensitive breeds. The ability to edit the genome makes it possible to design new genes that confer protection of cells from stresses like heat shock. PMID:25472041

  12. Differences in heat tolerance between preimplantation embryos from Brahman, Romosinuano, and Angus breeds.

    Hernández-Cerón, J; Chase, C C; Hansen, P J

    2004-01-01

    Exposure to 41 degrees C reduces development of embryos of heat-sensitive breeds (Holstein and Angus) more than for embryos of the heat-tolerant Brahman breed. Here it was tested whether embryonic resistance to heat shock occurs for a thermotolerant breed of different genetic origin than the Brahman. In particular, the thermal sensitivity of in vitro produced embryos of the Romosinuano, a Bos taurus, Criollo-derived breed, was compared to that for in vitro produced Brahman and Angus embryos. At d 4 after insemination, embryos > or = 8 cells were randomly assigned to control (38.5 degrees C) or heat shock (41 degrees C for 6 h) treatments. Heat shock reduced the proportion of embryos that developed to the blastocyst stage on d 8 after insemination. At 38.5 degrees C, there were no significant differences in development between breeds. Among embryos exposed to 41 degrees C, however, development was lower for Angus embryos than for Brahman and Romosinuano embryos. Furthermore, an Angus vs. (Brahman + Romosinuano) x temperature interaction occurred because heat shock reduced development more in Angus (30.3 +/- 4.6% at 38.5 degrees C vs. 4.9 +/- 4.6% at 41 degrees C) than in Brahman (25.1 +/- 4.6% vs. 13.6 +/- 4.6%) and Romosinuano (28.3 +/- 4.1% vs. 17.5 +/- 4.1%). Results demonstrate that embryos from Brahman and Romosinuano breeds are more resistant to elevated temperature than embryos from Angus. Thus, the process of adaptation of Brahman and Romosinuano breeds to hot environments resulted in both cases in selection of genes controlling thermotolerance at the cellular level. PMID:14765810

  13. Do Acquirer Capabilities Affect Acquisition Performance? Examining Strategic and Effectiveness Capabilities in Acquirers

    Mudde, Paul A.; Brush, Thomas

    2006-01-01

    This paper examines acquisition performance from the perspective of acquirer capabilities. It argues that the strategic capabilities underpinning a firm’s competitive strategy can be utilized to create economic value in acquisitions. Acquirers with strong cost leadership capabilities are expected to leverage these capabilities to reduce post-acquisition costs as they integrate acquisition targets. Acquirers with strong differentiation capabilities are expected to utilize their strategic capab...

  14. Understanding the Heat Shock Response in the Sea Cucumber Apostichopus japonicus, Using iTRAQ-Based Proteomics.

    Xu, Dongxue; Sun, Lina; Liu, Shilin; Zhang, Libin; Yang, Hongsheng

    2016-01-01

    The sea cucumber Apostichopus japonicus is exploited as a commercial species owing to their high nutritive and medicinal value. Recent high summer temperatures have caused high mortality rates in A. japonicus. In this study, we applied the isobaric tag for relative and absolute quantitation (iTRAQ) technique to investigate the global protein expression profile under an acute short-term (48 h) heat stress. In total, 3432 proteins were identified, and 127 proteins showed significant heat stress responses, with 61 upregulated proteins and 66 downregulated proteins. Our results suggest that heat stress influenced the expression of proteins involved in various biological processes, such as tissue protection and detoxification, lipid and amino acid metabolism, energy production and usage, transcription and translation, cell apoptosis, and cell proliferation. These findings provide a better understanding about the response and thermo-tolerance mechanisms of A. japonicus under heat stress. PMID:26861288

  15. Understanding the Heat Shock Response in the Sea Cucumber Apostichopus japonicus, Using iTRAQ-Based Proteomics

    Dongxue Xu

    2016-02-01

    Full Text Available The sea cucumber Apostichopus japonicus is exploited as a commercial species owing to their high nutritive and medicinal value. Recent high summer temperatures have caused high mortality rates in A. japonicus. In this study, we applied the isobaric tag for relative and absolute quantitation (iTRAQ technique to investigate the global protein expression profile under an acute short-term (48 h heat stress. In total, 3432 proteins were identified, and 127 proteins showed significant heat stress responses, with 61 upregulated proteins and 66 downregulated proteins. Our results suggest that heat stress influenced the expression of proteins involved in various biological processes, such as tissue protection and detoxification, lipid and amino acid metabolism, energy production and usage, transcription and translation, cell apoptosis, and cell proliferation. These findings provide a better understanding about the response and thermo-tolerance mechanisms of A. japonicus under heat stress.

  16. Acquired angioedema secondary to hormone replacement therapy

    Malani Kumar

    2005-10-01

    Full Text Available Angioedema is a potentially life threatening condition and may be either inherited or acquired. The latter is rare with only a handful of cases reported in the world literature. Presenting complaints are often vague. Those most commonly described include swelling in the subcutaneous and submucosal tissues. Patients presenting with laryngeal edema have high mortality, and high clinical suspicion is necessary to avoid instrumentation, which can precipitate laryngeal spasm. We present a review of reported cases of hormonally induced hereditary angioedema, along with a report of a patient with acquired angioedema secondary to hormone replacement therapy. To the best of our knowledge, this case probably represents the first reported case of acquired angioedema secondary to hormone replacement therapy.

  17. Evaluation of in vitro gas production and nutrient digestibility of complete diets supplemented with different levels of thermotolerant yeast in Nellore rams

    Ch. Harikrishna

    Full Text Available Aim: The objective of the present study was to know the effect of dietary supplementation of varied levels of thermotolerant yeast to determine best levels for sheep diets by in vitro gas production. An in vivo study on Nellore rams was used for further evaluation of diets with three best levels of yeast (obtained from in vitro data to determine diet with optimum yeast level for growing lambs by assessing nutrient digestibility, plane of nutrition and nitrogen balance. Materials and methods: A complete diet was formulated and supplemented with five levels (0 g/kg (D ; 1 g/kg (D ; 2 g/kg 1 2 (D ; 3 g/kg (D ; 4 g/kg (D and 5 g/kg (D of thermotolerant yeast (Saccharomyces cerevisiae, OBV-9 @ 5x108 cfu/g to 3 4 5 6 determine best levels for sheep diets by IVGP technique. An in vivo study was conducted on Nellore rams (39.75 0.24 kg body weight, aged 3 years in a 4 x 4 latin square design for further evaluation of diets with three best yeast levels based on in vitro data, to determine optimum yeast level for diets of growing lambs by assessing nutrient digestibility, plane of nutrition and nitrogen balance. The rams were housed individually in metabolic cages that allowed separation of urine and faeces to evaluate digestibility of nutrients and N balance. Animals were given 10 days adaptation period followed by 7-day collection period, feed intake and refusals were recorded. During the digestibility and N balance study, feed, refusals and faeces were analyzed for dry matter (DM, organic matter (OM and crude protein (CP as per AOAC, USA, while fibre fractions like neutral detergent fibre (aNDF and acid detergent fibre (ADF were analyzed. Data were analyzed as per the procedures suggested by Snedecor, G. W. and Cochran, W. G. (1994 and the difference between treatment means was tested for significance by Duncan's multiple-range and F Test. Results: Higher (P<0.01 IVGP volumes, in vitro organic matter degradability, metabolizable energy (ME and total

  18. Immunomodulation in community-acquired pneumonia

    Remmelts, H.H.F.

    2013-01-01

    Community-acquired pneumonia (CAP) is a common disease with considerable morbidity and mortality, despite effective antibiotic treatment. In this thesis, we showed that the major causative microorganisms in CAP trigger distinct inflammatory response profiles in the host. While an inflammatory respon

  19. Group Treatment in Acquired Brain Injury Rehabilitation

    Bertisch, Hilary; Rath, Joseph F.; Langenbahn, Donna M.; Sherr, Rose Lynn; Diller, Leonard

    2011-01-01

    The current article describes critical issues in adapting traditional group-treatment methods for working with individuals with reduced cognitive capacity secondary to acquired brain injury. Using the classification system based on functional ability developed at the NYU Rusk Institute of Rehabilitation Medicine (RIRM), we delineate the cognitive…

  20. Acquired secondary Grynfeltt's hernia: a case report

    Lumbar hernia is a rare condition whose diagnosis is hardly achieved. The prevalence is higher in elderly men. The present case report describes the case of a male, 78-year-old patient who underwent pleural effusion drainage 17 years before presenting with clinical manifestations and tomographic findings compatible with acquired secondary Grynfeltt's hernia. (author)

  1. Monitoring Agitated Behavior After acquired Brain Injury

    Aadal, Lena; Mortensen, Jesper; Nielsen, Jørgen Feldbaek

    2015-01-01

    Purpose: To describe the onset, duration, intensity, and nursing shift variation of agitated behavior in patients with acquired brain injury (ABI) at a rehabilitation hospital. Design: Prospective descriptive study. Methods: A total of 11 patients with agitated behavior were included. Agitated...

  2. Prevention of hospital-acquired hyponatraemia

    Lunøe, Mathilde; Overgaard-Steensen, C

    2015-01-01

    prevention of hospital-acquired hyponatraemia is an understanding of what determines plasma sodium concentration (P-[Na(+) ]) in the individual patient. P-[Na(+) ] is determined by balances of water and cations according to Edelman. This paper discusses the mechanisms influencing water and cation balances...

  3. Support Network Responses to Acquired Brain Injury

    Chleboun, Steffany; Hux, Karen

    2011-01-01

    Acquired brain injury (ABI) affects social relationships; however, the ways social and support networks change and evolve as a result of brain injury is not well understood. This study explored ways in which survivors of ABI and members of their support networks perceive relationship changes as recovery extends into the long-term stage. Two…

  4. Interviewing Children with Acquired Brain Injury (ABI)

    Boylan, Anne-Marie; Linden, Mark; Alderdice, Fiona

    2009-01-01

    Research into the lives of children with acquired brain injury (ABI) often neglects to incorporate children as participants, preferring to obtain the opinions of the adult carer (e.g. McKinlay et al., 2002). There has been a concerted attempt to move away from this position by those working in children's research with current etiquette…

  5. Sexually acquired Salmonella Typhi urinary tract infection.

    Wielding, Sally; Scott, Gordon

    2016-05-01

    We report a case of isolated urinarySalmonella entericaserotype Typhi in an HIV-positive man who has sex with men. He was clinically well and blood and stool cultures were negative, indicating that this may have been a sexually acquired urinary tract infection. PMID:25953964

  6. District heating

    The papers presented at this meeting dealt with an international comparison of district heating, the Swiss district heating network, political aspects of nuclear district heating, nuclear and non-nuclear sources for district heating. 17 figs., 6 tabs

  7. Heat Waves

    Heat Waves Dangers we face during periods of very high temperatures include: Heat cramps: These are muscular pains and spasms due ... that the body is having trouble with the heat. If a heat wave is predicted or happening… - ...

  8. The occurrence of heat-resistant species of .i.Trichophaea abundans./i. in different types of soil in Slovakia and Czech Republic

    Šimonovičová, A.; Nováková, Alena; Pangallo, D.; Hnátová, V.; Hubka, Vít

    2014-01-01

    Roč. 69, č. 2 (2014), s. 168-172. ISSN 0006-3088 R&D Projects: GA ČR GAP504/12/0536 Grant ostatní: VEGA(SK) 1/0156/11; Ministerstvo školstva, vedy výskumu a športu SR(SK) ITMS 26240120004 Institutional support: RVO:60077344 ; RVO:61388971 Keywords : burned soil * gradually heated and saturated soil sample * thermotolerance Subject RIV: EH - Ecology, Behaviour Impact factor: 0.827, year: 2014

  9. Sensing the Heat Stress by Mammalian Cells

    Cates Jordan

    2011-08-01

    consecutive shocks (i.e., no recovery time in between shocks depends on the order of the input shocks, that is the shocks do not commute; (ii the responses may be classified as mild or severe, depending on the temperature level and the duration of the heat shock and (iii the response is highly sensitive to small variations in temperature. Conclusions We propose a mathematical model that maps temperature into the transient activity using experimental data that describes the time course of the response to input thermal stress. The model is built on thermotolerance without recovery time, sharp sensitivity to small variations in temperature and the existence of mild and severe classes of stress responses. The theoretical predictions are tested against experimental data using a series of double-shock inputs. The theoretical structure is represented by a sequence of three cascade processes that transform the input stress into the transient activity. The structure of the cascade is nonlinear-linear-nonlinear (NLN. The first nonlinear system (N from the NLN structure represents the amplification of small changes in the environmental temperature; the linear system (L represents the thermotolerance without recovery time, whereas the last system (N represents the transition of the cell's response from a mild to a severe shock.

  10. Simultaneous saccharification and fermentation of delignified lignocellulosic biomass at high solid loadings by a newly isolated thermotolerant Kluyveromyces sp. for ethanol production.

    Narra, Madhuri; James, Jisha P; Balasubramanian, Velmurugan

    2015-03-01

    Simultaneous saccharification and fermentation studies were carried out using thermotolerant newly isolated Kluyveromyces sp. with three different delignified lignocellulosic biomass viz. rice straw, wheat straw and sugarcane bagasse at 5-15% solid loading and 6-12 FPU g(-1) substrate enzyme loading for different time intervals 0-72 h at 42°C. Maximum ethanol achieved from rice straw, wheat straw and sugarcane bagasse with in-house crude cellulases from Aspergillus terreus was 23.23, 18.29 and 17.91 mg mL(-1) at 60 h with 10% solid load and 9 FPU g(-1) substrate enzyme loading. Tween 80 1% (v/v) enhanced the ethanol yield by 8.39%, 9.26% and 8.14% in rice straw, wheat straw and sugarcane bagasse, respectively. External supplementation of β-glucosidase to the crude as well commercial cellulases produced maximum theoretical ethanol yield of 71.76%, 63.77%, 57.15% and 84.56%, 72.47%, 70.55% from rice straw, wheat straw and sugarcane bagasse, respectively. PMID:25553563

  11. The effect of soluble alginate and calcium on {beta}-galactosidase activity produced by the thermotolerant, ethanol-producing yeast strain Kluyveromyces marxianus imb3

    Brady, D.; Logan, S.R.; McHale, A.P. [Biotechnology Research Group, School of Applied Biological and Chemical Sciences, University of Ulster, Coleraine, Co. Londonderry, BT52 1SA (United Kingdom)

    1998-02-01

    Since it has previously been demonstrated that ethanol production by the thermotolerant yeast strain, Kluyveromyces marxianus IMB3 is more efficient in calcium alginate-based immobilization systems during growth on lactose-containing media, it was decided to examine the separate effects of soluble alginate and free calcium on the {beta}-galactosidase activity produced by that organism. It was found that the presence of Ca{sup 2+} significantly increased the thermal stability of the activity at 45 C, although the pH and temperature optima remained the same in the presence and absence of that cation. It was also found that the presence of 2% (w/v) sodium alginate (soluble) had a very limited positive effect on the thermal stability of the enzyme at 45 C, although it was found that activity was very significantly stimulated at that temperature. The activity was found to have an enhanced thermal stability at 30 C in the presence of sodium alginate. The presence of sodium alginate in assay mixtures had no significant effect on the Km of the activity for the substrate o-nitrophenyl-{beta}-D-galactoside. The results observed in the presence of either free calcium or soluble alginate may at least partially explain enhanced ethanol production by this microorganism in alginate-based immobilization systems. (orig.) With 2 figs., 14 refs.

  12. The profile of antibiotics resistance and integrons of extended-spectrum beta-lactamase producing thermotolerant coliforms isolated from the Yangtze River basin in Chongqing

    The spreading of extended-spectrum β-lactamases (ESBL)-producing thermotolerant coliforms (TC) in the water environment is a threat to human health but little is known about ESBL-producing TCs in the Yangtze River. We received 319 ESBL-producing stains obtained from the Chongqing basin and we investigated antibiotic susceptibility, bla gene types and the presence of integrons and gene cassettes. 16.8% of TC isolates were ESBL-producing bacteria and blaTEM+CTx-M was the predominant ESBL type. 65.2% of isolates contained class 1 integrons, but only 3 carried intI 2. Gene cassettes were amplified and sequenced. aadA, drfA, cmlA, sat1, aar3 and two ORF cassettes were found. In conclusion, Yangtze River is heavily polluted by ESBL-producing TC bacteria and the combined bla gene type could enhance antibiotic resistance. Class 1 integrons were widespread in ESBL-producing isolates and play an important role in multi-drug resistance. Characterization of gene cassettes could reveal the dissemination of antibiotic resistance genes. - Yangtze River is heavily polluted by ESBL-producing TC bacteria and Class 1 integrons play an important role in multi-drug resistance.

  13. The transcription factor SKN7 regulates conidiation, thermotolerance, apoptotic-like cell death and parasitism in the nematode endoparasitic fungus Hirsutella minnesotensis.

    Hussain, Muzammil; Hamid, M Imran; Wang, Niuniu; Bin, Lin; Xiang, Meichun; Liu, Xingzhong

    2016-01-01

    The transcription factor SKN7 is a highly conserved protein among fungi and was initially recognized as a response regulator that protects cells from oxidative stress and maintains cell wall integrity in yeast. Orthologs of SKN7 are extensively present in biocontrol agents of plant pathogens, but they had not been functionally characterized. Here, we identified and characterized the transcription factor SKN7 in the nematode endoparasitic fungus Hirsutella minnesotensis. Null mutant lacking HIM-SKN7 (HIM_03620), which was generated by a gene disruption strategy, demonstrated reduced conidiation, increased sensitivity to high temperature, hydrogen peroxide, mannitol and ethanol, and reduced fungal resistance to farnesol. However, over-expression mutant showed increased conidial production, thermotolerance and resistance to farnesol, suggesting that HIM-SKN7 regulates antiapoptotic-like cell death in H. minnesotensis. Moreover, the results showed that in null mutant, H. minnesotensis had decreased endoparasitic ability as compared to wild type and over-expression strain. During the infection process, the relative expression of the HIM-SKN7 gene was significantly induced in the wild type and over-expression strain. The results of the present study advance our understanding of the functions of the SKN7 gene in biocontrol agents, in particular, nematode endoparasitic fungi. PMID:27436205

  14. Rapid ethanol production at elevated temperatures by engineered thermotolerant Kluyveromyces marxianus via the NADP(H)-preferring xylose reductase-xylitol dehydrogenase pathway.

    Zhang, Jia; Zhang, Biao; Wang, Dongmei; Gao, Xiaolian; Sun, Lianhong; Hong, Jiong

    2015-09-01

    Conversion of xylose to ethanol by yeasts is a challenge because of the redox imbalances under oxygen-limited conditions. The thermotolerant yeast Kluyveromyces marxianus grows well with xylose as a carbon source at elevated temperatures, but its xylose fermentation ability is weak. In this study, a combination of the NADPH-preferring xylose reductase (XR) from Neurospora crassa and the NADP(+)-preferring xylitol dehydrogenase (XDH) mutant from Scheffersomyces stipitis (Pichia stipitis) was constructed. The xylose fermentation ability and redox balance of the recombinant strains were improved significantly by over-expression of several downstream genes. The intracellular concentrations of coenzymes and the reduced coenzyme/oxidized coenzyme ratio increased significantly in these metabolic strains. The byproducts, such as glycerol and acetic acid, were significantly reduced by the disruption of glycerol-3-phosphate dehydrogenase (GPD1). The resulting engineered K. marxianus YZJ088 strain produced 44.95 g/L ethanol from 118.39 g/L xylose with a productivity of 2.49 g/L/h at 42 °C. Additionally, YZJ088 realized glucose and xylose co-fermentation and produced 51.43 g/L ethanol from a mixture of 103.97 g/L xylose and 40.96 g/L glucose with a productivity of 2.14 g/L/h at 42 °C. These promising results validate the YZJ088 strain as an excellent producer of ethanol from xylose through the synthetic xylose assimilation pathway. PMID:26253204

  15. Recovery from bleaching is mediated by threshold densities of background thermo-tolerant symbiont types in a reef-building coral

    Bay, Line K.; Doyle, Jason; Logan, Murray; Berkelmans, Ray

    2016-01-01

    Sensitive molecular analyses show that most corals host a complement of Symbiodinium genotypes that includes thermo-tolerant types in low abundance. While tolerant symbiont types are hypothesized to facilitate tolerance to temperature and recovery from bleaching, empirical data on their distribution and relative abundance in corals under ambient and stress conditions are still rare. We quantified visual bleaching and mortality of coral hosts, along with relative abundance of C- and D-type Symbiodinium cells in 82 Acropora millepora colonies from three locations on the Great Barrier Reef transplanted to a central inshore site over a 13 month period. Our analyses reveal dynamic change in symbiont associations within colonies and among populations over time. Coral bleaching and declines in C- but not D-type symbionts were observed in transplanted corals. Survival and recovery of 25% of corals from one population was associated with either initial D-dominance or an increase in D-type symbionts that could be predicted by a minimum pre-stress D : C ratio of 0.003. One-third of corals from this population became D dominated at the bleached stage despite no initial detection of this symbiont type, but failed to recover and died in mid to late summer. These results provide a predictive threshold minimum density of background D-type symbionts in A. millepora, above which survival following extreme thermal stress is increased. PMID:27429786

  16. Recovery from bleaching is mediated by threshold densities of background thermo-tolerant symbiont types in a reef-building coral.

    Bay, Line K; Doyle, Jason; Logan, Murray; Berkelmans, Ray

    2016-06-01

    Sensitive molecular analyses show that most corals host a complement of Symbiodinium genotypes that includes thermo-tolerant types in low abundance. While tolerant symbiont types are hypothesized to facilitate tolerance to temperature and recovery from bleaching, empirical data on their distribution and relative abundance in corals under ambient and stress conditions are still rare. We quantified visual bleaching and mortality of coral hosts, along with relative abundance of C- and D-type Symbiodinium cells in 82 Acropora millepora colonies from three locations on the Great Barrier Reef transplanted to a central inshore site over a 13 month period. Our analyses reveal dynamic change in symbiont associations within colonies and among populations over time. Coral bleaching and declines in C- but not D-type symbionts were observed in transplanted corals. Survival and recovery of 25% of corals from one population was associated with either initial D-dominance or an increase in D-type symbionts that could be predicted by a minimum pre-stress D : C ratio of 0.003. One-third of corals from this population became D dominated at the bleached stage despite no initial detection of this symbiont type, but failed to recover and died in mid to late summer. These results provide a predictive threshold minimum density of background D-type symbionts in A. millepora, above which survival following extreme thermal stress is increased. PMID:27429786

  17. Production of a Solvent, Detergent, and Thermotolerant Lipase by a Newly Isolated Acinetobacter sp. in Submerged and Solid-State Fermentations

    Anahita Khoramnia

    2011-01-01

    Full Text Available The lipase production ability of a newly isolated Acinetobacter sp. in submerged (SmF and solid-state (SSF fermentations was evaluated. The results demonstrated this strain as one of the rare bacterium, which is able to grow and produce lipase in SSF even more than SmF. Coconut oil cake as a cheap agroindustrial residue was employed as the solid substrate. The lipase production was optimized in both media using artificial neural network. Multilayer normal and full feed forward backpropagation networks were selected to build predictive models to optimize the culture parameters for lipase production in SmF and SSF systems, respectively. The produced models for both systems showed high predictive accuracy where the obtained conditions were close together. The produced enzyme was characterized as a thermotolerant lipase, although the organism was mesophile. The optimum temperature for the enzyme activity was 45°C where 63% of its activity remained at 70°C after 2 h. This lipase remained active after 24 h in a broad range of pH (6–11. The lipase demonstrated strong solvent and detergent tolerance potentials. Therefore, this inexpensive lipase production for such a potent and industrially valuable lipase is promising and of considerable commercial interest for biotechnological applications.

  18. Production of a solvent, detergent, and thermotolerant lipase by a newly isolated Acinetobacter sp. in submerged and solid-state fermentations.

    Khoramnia, Anahita; Ebrahimpour, Afshin; Beh, Boon Kee; Lai, Oi Ming

    2011-01-01

    The lipase production ability of a newly isolated Acinetobacter sp. in submerged (SmF) and solid-state (SSF) fermentations was evaluated. The results demonstrated this strain as one of the rare bacterium, which is able to grow and produce lipase in SSF even more than SmF. Coconut oil cake as a cheap agroindustrial residue was employed as the solid substrate. The lipase production was optimized in both media using artificial neural network. Multilayer normal and full feed forward backpropagation networks were selected to build predictive models to optimize the culture parameters for lipase production in SmF and SSF systems, respectively. The produced models for both systems showed high predictive accuracy where the obtained conditions were close together. The produced enzyme was characterized as a thermotolerant lipase, although the organism was mesophile. The optimum temperature for the enzyme activity was 45°C where 63% of its activity remained at 70°C after 2 h. This lipase remained active after 24 h in a broad range of pH (6-11). The lipase demonstrated strong solvent and detergent tolerance potentials. Therefore, this inexpensive lipase production for such a potent and industrially valuable lipase is promising and of considerable commercial interest for biotechnological applications. PMID:21960739

  19. Effects of temperature, pH-values and sodium chloride concentrations on the glucose-6-phosphate dehydrogenase activity by thermotolerant Bacillus strains

    HAZEM AQEL

    2012-01-01

    Full Text Available Thirteen new isolated thermotolerant Bacillus strains and four known Bacillus species were used to evaluate the effect of growth temperature, pH-values and NaCl concentrations on the intracellular glucose-6-phosphate dehydrogenase (G6PDH activity. Results had shown a significant difference in G6PDH production among all species at all used temperatures (p<0.05. The response of individual new isolates and controls for production of G6PDH under growth conditions was variable. The optimal growth conditions did not correspond to the optimal cultivation conditions for maximum G6PDH production. The growth temperature showed the most significant effect on G6PDH activity. The combined effect of temperature and NaCl on the G6PDH activity was strongly pronounced in comparison with the combined effect of temperature and pH or pH and NaCl. Thermal stability at 53ºC and electrophoretic mobility were also investigated. G6PDH from HUTB41 was the most thermostable G6PDH enzyme with T50% of more than 360 minutes. Electrophoretic study demonstrated that G6PDH was composed of two isoenzymes for all strains except B. marinus and B. schlegelii that had three isoenzymes.

  20. The profile of antibiotics resistance and integrons of extended-spectrum beta-lactamase producing thermotolerant coliforms isolated from the Yangtze River basin in Chongqing

    Chen Hao [Department of Environmental Hygiene, School of Military Preventive Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing 400038 (China); Shu Weiqun, E-mail: west2003@sohu.co [Department of Environmental Hygiene, School of Military Preventive Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing 400038 (China); Chang Xiaosong; Chen Jian; Guo Yebin; Tan Yao [Department of Environmental Hygiene, School of Military Preventive Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing 400038 (China)

    2010-07-15

    The spreading of extended-spectrum {beta}-lactamases (ESBL)-producing thermotolerant coliforms (TC) in the water environment is a threat to human health but little is known about ESBL-producing TCs in the Yangtze River. We received 319 ESBL-producing stains obtained from the Chongqing basin and we investigated antibiotic susceptibility, bla gene types and the presence of integrons and gene cassettes. 16.8% of TC isolates were ESBL-producing bacteria and bla{sub TEM+CTx-M} was the predominant ESBL type. 65.2% of isolates contained class 1 integrons, but only 3 carried intI 2. Gene cassettes were amplified and sequenced. aadA, drfA, cmlA, sat1, aar3 and two ORF cassettes were found. In conclusion, Yangtze River is heavily polluted by ESBL-producing TC bacteria and the combined bla gene type could enhance antibiotic resistance. Class 1 integrons were widespread in ESBL-producing isolates and play an important role in multi-drug resistance. Characterization of gene cassettes could reveal the dissemination of antibiotic resistance genes. - Yangtze River is heavily polluted by ESBL-producing TC bacteria and Class 1 integrons play an important role in multi-drug resistance.

  1. Cultivation of two thermotolerant microalgae under tropical conditions: Influences of carbon sources and light duration on biomass and lutein productivity in four seasons.

    Chiu, Pai-Ho; Soong, Keryea; Chen, Ching-Nen Nathan

    2016-07-01

    Biomass and lutein productivities of two thermotolerant microalgae were assessed in tropical outdoor conditions in all four seasons. Generally, addition of bicarbonate at 0.2g/L every two days or 2% CO2 did not enhance the productivities compared to the controls, and the productivities in the spring were higher than in the fall. Durations of effective irradiance positively correlated to the productivity of Coelastrella sp. F50 well, but not for Desmodesmus sp. F2. The ineffective light intensity was below 5000 lux (about 106μmol/m(2)s). The productivities produced in the 17cm diameter bottles were 1.5- to 1.9-fold higher than that in the 27cm ones. Lutein content, about 0.5% in biomass on average, did not change significantly grown in different carbon sources or seasons. The annual productivities of the microalgal biomass and lutein in one hectare were estimated to be 33tons and 180kg, respectively, using the non-optimized photobioreactor cultivation. PMID:27099944

  2. Immunological memory and acquired immunodeficiency syndrome pathogenesis.

    Kaur, A; Rosenzweig, M; Johnson, R. P.

    2000-01-01

    Infection with the human immunodeficiency virus results in profound perturbations in immunological memory, ultimately resulting in increased susceptibility to opportunistic infections and acquired immunodeficiency syndrome (AIDS). We have used rhesus macaques infected with the simian immunodeficiency virus (SIV) as a model to understand better the effects of AIDS virus infection on immunological memory. Acute infection with SIV resulted in significant deficits in CD4+ helper responses to cyto...

  3. Economics and Preventing Hospital-acquired Infection

    Graves, Nicholas

    2004-01-01

    The economics of preventing hospital-acquired infections is most often described in general terms. The underlying concepts and mechanisms are rarely made explicit but should be understood for research and policy-making. We define the key economic concepts and specify an illustrative model that uses hypothetical data to identify how two related questions might be addressed: 1) how much should be invested for infection control, and 2) what are the most appropriate infection-control programs? We...

  4. Acquired resistance to immunotherapy and future challenges.

    Restifo, Nicholas P; Smyth, Mark J; Snyder, Alexandra

    2016-02-01

    Advances in immunotherapy have resulted in remarkable clinical responses in some patients. However, one of the biggest challenges in cancer therapeutics is the development of resistant disease and disease progression on or after therapy. Given that many patients have now received various types of immunotherapy, we asked three scientists to give their views on the current evidence for whether acquired resistance to immunotherapy exists in patients and the future challenges posed by immunotherapy. PMID:26822578

  5. Molecular biological aspects of acquired bullous diseases

    Dabelsteen, Erik

    1998-01-01

    genes have been cloned. The antigens which react with autoantibodies from patients with bullous pemphigoid, cicatricial pemphigoid, acquired epidermolysis bullosa, and linear IgA disease are all proteins of the hemidesmosome basement membrane complex. Interestingly, most of the antigens also appear to...... be the target for mutations seen in patients with the inherited type of epidermolysis bullosa in which bullous lesions are a prominent clinical feature....

  6. Processed pseudogenes acquired somatically during cancer development

    Cooke, Susanna L.; Shlien, Adam; Marshall, John; Pipinikas, Christodoulos P; Martincorena, Inigo; Tubio, Jose M. C.; Li, Yilong; Menzies, Andrew; Mudie, Laura; Ramakrishna, Manasa; Yates, Lucy; Davies, Helen; Bolli, Niccolo; Bignell, Graham R; Tarpey, Patrick S.

    2014-01-01

    Cancer evolves by mutation, with somatic reactivation of retrotransposons being one such mutational process. Germline retrotransposition can cause processed pseudogenes, but whether this occurs somatically has not been evaluated. Here we screen sequencing data from 660 cancer samples for somatically acquired pseudogenes. We find 42 events in 17 samples, especially non-small cell lung cancer (5/27) and colorectal cancer (2/11). Genomic features mirror those of germline LINE element retrotransp...

  7. Earth Knowledge Acquired by Middle School Students

    Ride, Sally

    2008-01-01

    Earth Knowledge Acquired by Middle School Students (EarthKAM), an education activity, allows middle school students to program a digital camera on board the International Space Station to photograph a variety of geographical targets for study in the classroom. Photos are made available on the web for viewing and study by participating schools around the world. Educators use the images for projects involving Earth Science, geography, physics, and social science.

  8. Brucella abortus Infection Acquired in Microbiology Laboratories

    Fiori, Pier Luigi; Mastrandrea, Scilla; Rappelli, Paola; Cappuccinelli, Piero

    2000-01-01

    We report an outbreak of laboratory-acquired Brucella abortus infection originating in the accidental breakage of a centrifuge tube. A total of 12 laboratory workers were infected (attack rate of 31%), with an incubation time ranging from 6 weeks to 5 months. Antibody titers were evaluated weekly in all personnel exposed, allowing the diagnosis of the infection in most cases before the onset of clinical symptoms, so that specific therapy could be administrated.

  9. A CMA position. Acquired immunodeficiency syndrome.

    1989-01-01

    The following general principles serve as guidelines for various bodies, health care professionals and the general public. Specific aspects of infection with human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) that relate to physicians' ethical responsibilities as well as society's moral obligations are discussed. Such matters include the need for education, research and treatment resources; the patient's right to investigation and treatment and to refusal of eith...

  10. Clinicopathological correlation of acquired hyperpigmentary disorders

    Anisha B Patel; Raj Kubba; Asha Kubba

    2013-01-01

    Acquired pigmentary disorders are group of heterogenous entities that share single, most significant, clinical feature, that is, dyspigmentation. Asians and Indians, in particular, are mostly affected. Although the classic morphologies and common treatment options of these conditions have been reviewed in the global dermatology literature, the value of histpathological evaluation has not been thoroughly explored. The importance of accurate diagnosis is emphasized here as the underlying diseas...

  11. MRI of fetal acquired brain lesions

    Acquired fetal brain damage is suspected in cases of destruction of previously normally formed tissue, the primary cause of which is hypoxia. Fetal brain damage may occur as a consequence of acute or chronic maternal diseases, with acute diseases causing impairment of oxygen delivery to the fetal brain, and chronic diseases interfering with normal, placental development. Infections, metabolic diseases, feto-fetal transfusion syndrome, toxic agents, mechanical traumatic events, iatrogenic accidents, and space-occupying lesions may also qualify as pathologic conditions that initiate intrauterine brain damage. MR manifestations of acute fetal brain injury (such as hemorrhage or acute ischemic lesions) can easily be recognized, as they are hardly different from postnatal lesions. The availability of diffusion-weighted sequences enhances the sensitivity in recognizing acute ischemic lesions. Recent hemorrhages are usually readily depicted on T2 (*) sequences, where they display hypointense signals. Chronic fetal brain injury may be characterized by nonspecific changes that must be attributable to the presence of an acquired cerebral pathology. The workup in suspected acquired fetal brain injury also includes the assessment of extra-CNS organs that may be affected by an underlying pathology. Finally, the placenta, as the organ that mediates oxygen delivery from the maternal circulation to the fetus, must be examined on MR images

  12. MRI of fetal acquired brain lesions

    Prayer, Daniela [Department of Radiodiagnostics, Medical University of Vienna (Austria)]. E-mail: daniela.prayer@meduniwien.ac.at; Brugger, Peter C. [Center of Anatomy and Cell Biology, Medical University of Vienna (Austria); Kasprian, Gregor [Department of Radiodiagnostics, Medical University of Vienna (Austria); Witzani, Linde [Department of Radiodiagnostics, Medical University of Vienna (Austria); Helmer, Hanns [Department of Obstetrics and Gynecology, Medical University of Vienna (Austria); Dietrich, Wolfgang [Department of Neurosurgery, Medical University of Vienna (Austria); Eppel, Wolfgang [Department of Obstetrics and Gynecology, Medical University of Vienna (Austria); Langer, Martin [Department of Obstetrics and Gynecology, Medical University of Vienna (Austria)

    2006-02-15

    Acquired fetal brain damage is suspected in cases of destruction of previously normally formed tissue, the primary cause of which is hypoxia. Fetal brain damage may occur as a consequence of acute or chronic maternal diseases, with acute diseases causing impairment of oxygen delivery to the fetal brain, and chronic diseases interfering with normal, placental development. Infections, metabolic diseases, feto-fetal transfusion syndrome, toxic agents, mechanical traumatic events, iatrogenic accidents, and space-occupying lesions may also qualify as pathologic conditions that initiate intrauterine brain damage. MR manifestations of acute fetal brain injury (such as hemorrhage or acute ischemic lesions) can easily be recognized, as they are hardly different from postnatal lesions. The availability of diffusion-weighted sequences enhances the sensitivity in recognizing acute ischemic lesions. Recent hemorrhages are usually readily depicted on T2 (*) sequences, where they display hypointense signals. Chronic fetal brain injury may be characterized by nonspecific changes that must be attributable to the presence of an acquired cerebral pathology. The workup in suspected acquired fetal brain injury also includes the assessment of extra-CNS organs that may be affected by an underlying pathology. Finally, the placenta, as the organ that mediates oxygen delivery from the maternal circulation to the fetus, must be examined on MR images.

  13. Acquired Factor VIII Inhibitors: Three Cases

    Tay Za Kyaw

    2013-03-01

    Full Text Available Acquired hemophilia A is a rare, but devastating bleeding disorder caused by spontaneous development of autoantibodies directed against coagulation factor VIII. In 40%-50% of patients it is associated with such conditions as the postpartum period, malignancy, use of medications, and autoimmune diseases; however, its cause is unknown in most cases. Acquired hemophilia A should be suspected in patients that present with a coagulation abnormality, and a negative personal and family history of bleeding. Herein we report 3 patients with acquired hemophilia A that had different underlying pathologies, clinical presentations, and therapeutic responses. Factor VIII inhibitor formation in case 1 occurred 6 months after giving birth; underlying disorders were not identified in cases 2 or 3. The bleeding phenotype in these patients’ ranged from no bleeding tendency with isolated prolongation of APTT (activated partial thromboplastin time to severe intramuscular hematoma and hemarthrosis necessitating recombinant activated factor VII infusion and blood components transfusion. Variable responses to immunosuppressive treatment were also observed.

  14. Integrative analysis of the heat shock response in Aspergillus fumigatus

    Brakhage Axel A

    2010-01-01

    Full Text Available Abstract Background Aspergillus fumigatus is a thermotolerant human-pathogenic mold and the most common cause of invasive aspergillosis (IA in immunocompromised patients. Its predominance is based on several factors most of which are still unknown. The thermotolerance of A. fumigatus is one of the traits which have been assigned to pathogenicity. It allows the fungus to grow at temperatures up to and above that of a fevered human host. To elucidate the mechanisms of heat resistance, we analyzed the change of the A. fumigatus proteome during a temperature shift from 30°C to 48°C by 2D-fluorescence difference gel electrophoresis (DIGE. To improve 2D gel image analysis results, protein spot quantitation was optimized by missing value imputation and normalization. Differentially regulated proteins were compared to previously published transcriptome data of A. fumigatus. The study was augmented by bioinformatical analysis of transcription factor binding sites (TFBSs in the promoter region of genes whose corresponding proteins were differentially regulated upon heat shock. Results 91 differentially regulated protein spots, representing 64 different proteins, were identified by mass spectrometry (MS. They showed a continuous up-, down- or an oscillating regulation. Many of the identified proteins were involved in protein folding (chaperones, oxidative stress response, signal transduction, transcription, translation, carbohydrate and nitrogen metabolism. A correlation between alteration of transcript levels and corresponding proteins was detected for half of the differentially regulated proteins. Interestingly, some previously undescribed putative targets for the heat shock regulator Hsf1 were identified. This provides evidence for Hsf1-dependent regulation of mannitol biosynthesis, translation, cytoskeletal dynamics and cell division in A. fumigatus. Furthermore, computational analysis of promoters revealed putative binding sites for an AP-2alpha

  15. Change in algal symbiont communities after bleaching, not prior heat exposure, increases heat tolerance of reef corals.

    Silverstein, Rachel N; Cunning, Ross; Baker, Andrew C

    2015-01-01

    Mutualistic organisms can be particularly susceptible to climate change stress, as their survivorship is often limited by the most vulnerable partner. However, symbiotic plasticity can also help organisms in changing environments by expanding their realized niche space. Coral-algal (Symbiodinium spp.) symbiosis exemplifies this dichotomy: the partnership is highly susceptible to 'bleaching' (stress-induced symbiosis breakdown), but stress-tolerant symbionts can also sometimes mitigate bleaching. Here, we investigate the role of diverse and mutable symbiotic partnerships in increasing corals' ability to thrive in high temperature conditions. We conducted repeat bleaching and recovery experiments on the coral Montastraea cavernosa, and used quantitative PCR and chlorophyll fluorometry to assess the structure and function of Symbiodinium communities within coral hosts. During an initial heat exposure (32 °C for 10 days), corals hosting only stress-sensitive symbionts (Symbiodinium C3) bleached, but recovered (at either 24 °C or 29 °C) with predominantly (>90%) stress-tolerant symbionts (Symbiodinium D1a), which were not detected before bleaching (either due to absence or extreme low abundance). When a second heat stress (also 32 °C for 10 days) was applied 3 months later, corals that previously bleached and were now dominated by D1a Symbiodinium experienced less photodamage and symbiont loss compared to control corals that had not been previously bleached, and were therefore still dominated by Symbiodinium C3. Additional corals that were initially bleached without heat by a herbicide (DCMU, at 24 °C) also recovered predominantly with D1a symbionts, and similarly lost fewer symbionts during subsequent thermal stress. Increased thermotolerance was also not observed in C3-dominated corals that were acclimated for 3 months to warmer temperatures (29 °C) before heat stress. These findings indicate that increased thermotolerance post-bleaching resulted from

  16. Evaluation of Serratia and Pseudomonas in hospital acquired infection

    Etemadi H; Zahedani Sh

    1996-01-01

    Hospital acquired infection have 2 origins: 1) Infections acquired from the hospitalization. 2) Infections that transmit from hospital personnel and those who referred to a hospital. According to the studies approximately half of hospital acquired infection is under the first group. Gram-negative bacilli is of prime importance from all bacteries that caused hospital acquired infection. There are 3 main ways spreading hospital acquired infections include: 1) Auto infections 2) Transmit infecti...

  17. Sigmoid plate dehiscence: Congenital or acquired condition?

    Highlights: • CT with multiplanar reformations can accurately display the sigmoid platet dehiscence. • The prevalence of sigmoid plate dehiscence was no significant difference among different age groups. • The size of sigmoid plate bony defects were not statistically different among different age groups. • The sigmoid plate dehiscence is more commonly a congenital than an acquired condition. - Abstract: Background and purpose: The imaging features of sigmoid plate dehiscence-induced pulsatile tinnitus have been presented. The origin of the sigmoid plate dehiscence, however, remains unclear. Our aim was to assess the prevalence and extent of sigmoid plate dehiscence on computed tomography (CT) images in multiple age groups to determine whether this condition is more likely to be congenital or acquired. Materials and methods: We retrospectively reviewed contrast-enhanced CT images of sigmoid plates of temporal bones in 504 patients. Each temporal bone was characterized as normal or dehiscent. Patients were then subcategorized into four age groups, and the prevalence and extent of dehiscent sigmoid plates in each group were calculated and compared. Results: Overall, 80 patients had sigmoid plate dehiscence, nine of whom had it bilaterally. In successively older age groups, the prevalences of sigmoid plate dehiscence were 18.9%, 20.1%, 14.5%, and 12.7%, respectively. Respective average anteroposterior bony defect diameters were 3.7 ± 1.7, 3.0 ± 1.3, 3.1 ± 1.5, and 3.0 ± 1.1 mm. Respective average vertical bony defect diameters were 3.6 ± 2.3, 2.6 ± 1.2, 3.2 ± 1.5, and 3.0 ± 1.7 mm. The prevalence and extent of sigmoid plate dehiscence were not statistically different among the four age groups. Conclusions: The similar radiologic prevalence and extent of dehiscent sigmoid plates among the age groups suggest that the dehiscence is more commonly a congenital than an acquired condition

  18. Sigmoid plate dehiscence: Congenital or acquired condition?

    Liu, Zhaohui, E-mail: lzhtrhos@163.com [Capital Medical University, Beijing Tongren Hospital, No 1 Dong Jiao Min Street, Dongcheng District, Beijing 100730 (China); Li, Jing, E-mail: lijingxbh@yahoo.com.cn [Capital Medical University, Beijing Tongren Hospital, No 1 Dong Jiao Min Street, Dongcheng District, Beijing 100730 (China); Zhao, Pengfei, E-mail: zhaopengf05@163.com [Capital Medical University, Beijing Friendship Hospital, No 95 Yongan Road, Xicheng District, Beijing 100050 (China); Lv, Han, E-mail: chrislvhan@126.com [Capital Medical University, Beijing Friendship Hospital, No 95 Yongan Road, Xicheng District, Beijing 100050 (China); Dong, Cheng, E-mail: derc007@sina.com [Capital Medical University, Beijing Friendship Hospital, No 95 Yongan Road, Xicheng District, Beijing 100050 (China); Liu, Wenjuan, E-mail: wenjuanliu@163.com [Jining No. 1 People' s Hospital, No. 6 Health Street, Jining 272100 (China); Wang, Zhenchang, E-mail: cjr.wzhch@vip.163.com [Capital Medical University, Beijing Friendship Hospital, No 95 Yongan Road, Xicheng District, Beijing 100050 (China)

    2015-05-15

    Highlights: • CT with multiplanar reformations can accurately display the sigmoid platet dehiscence. • The prevalence of sigmoid plate dehiscence was no significant difference among different age groups. • The size of sigmoid plate bony defects were not statistically different among different age groups. • The sigmoid plate dehiscence is more commonly a congenital than an acquired condition. - Abstract: Background and purpose: The imaging features of sigmoid plate dehiscence-induced pulsatile tinnitus have been presented. The origin of the sigmoid plate dehiscence, however, remains unclear. Our aim was to assess the prevalence and extent of sigmoid plate dehiscence on computed tomography (CT) images in multiple age groups to determine whether this condition is more likely to be congenital or acquired. Materials and methods: We retrospectively reviewed contrast-enhanced CT images of sigmoid plates of temporal bones in 504 patients. Each temporal bone was characterized as normal or dehiscent. Patients were then subcategorized into four age groups, and the prevalence and extent of dehiscent sigmoid plates in each group were calculated and compared. Results: Overall, 80 patients had sigmoid plate dehiscence, nine of whom had it bilaterally. In successively older age groups, the prevalences of sigmoid plate dehiscence were 18.9%, 20.1%, 14.5%, and 12.7%, respectively. Respective average anteroposterior bony defect diameters were 3.7 ± 1.7, 3.0 ± 1.3, 3.1 ± 1.5, and 3.0 ± 1.1 mm. Respective average vertical bony defect diameters were 3.6 ± 2.3, 2.6 ± 1.2, 3.2 ± 1.5, and 3.0 ± 1.7 mm. The prevalence and extent of sigmoid plate dehiscence were not statistically different among the four age groups. Conclusions: The similar radiologic prevalence and extent of dehiscent sigmoid plates among the age groups suggest that the dehiscence is more commonly a congenital than an acquired condition.

  19. Acquired prosopagnosia without word recognition deficits.

    Susilo, Tirta; Wright, Victoria; Tree, Jeremy J; Duchaine, Bradley

    2015-01-01

    It has long been suggested that face recognition relies on specialized mechanisms that are not involved in visual recognition of other object categories, including those that require expert, fine-grained discrimination at the exemplar level such as written words. But according to the recently proposed many-to-many theory of object recognition (MTMT), visual recognition of faces and words are carried out by common mechanisms [Behrmann, M., & Plaut, D. C. ( 2013 ). Distributed circuits, not circumscribed centers, mediate visual recognition. Trends in Cognitive Sciences, 17, 210-219]. MTMT acknowledges that face and word recognition are lateralized, but posits that the mechanisms that predominantly carry out face recognition still contribute to word recognition and vice versa. MTMT makes a key prediction, namely that acquired prosopagnosics should exhibit some measure of word recognition deficits. We tested this prediction by assessing written word recognition in five acquired prosopagnosic patients. Four patients had lesions limited to the right hemisphere while one had bilateral lesions with more pronounced lesions in the right hemisphere. The patients completed a total of seven word recognition tasks: two lexical decision tasks and five reading aloud tasks totalling more than 1200 trials. The performances of the four older patients (3 female, age range 50-64 years) were compared to those of 12 older controls (8 female, age range 56-66 years), while the performances of the younger prosopagnosic (male, 31 years) were compared to those of 14 younger controls (9 female, age range 20-33 years). We analysed all results at the single-patient level using Crawford's t-test. Across seven tasks, four prosopagnosics performed as quickly and accurately as controls. Our results demonstrate that acquired prosopagnosia can exist without word recognition deficits. These findings are inconsistent with a key prediction of MTMT. They instead support the hypothesis that face

  20. Acquired Congenital Malalignment of the Great Toenails

    Decker, Ashley; Scher, Richard K.; Avarbock, Andrew

    2016-01-01

    Congenital malalignment is the lateral deviation of the nail plate along the longitudinal axis due to the lateral rotation of the nail matrix. The nail plate grows out in ridges caused by repeated microtrauma to the nail. Common complications include onychomycosis, Pseudomonas infection and acute or chronic paronychia. Treatment options range from conservative management to surgical options including realignment and nail matrixectomy. Congenital malalignment usually presents in infancy or childhood, but we present two cases of acquired malalignment occurring in the teenage years. PMID:27171597

  1. Cerebral involvement in acquired immunodeficiency syndrome (AIDS)

    Involvement of the central nervous system in acquired immune deficiency syndrome (AIDS) is usually due to opportunistic infections; these frequently offer a difficult differential diagnostic problem. Imaging methods play an important part in the elucidation of symptoms. CT and MR findings were analysed in 13 patients with AIDS and neurological symptoms. Some infections of the central nervous system (encephalitis of unknown aetiology, cytomegalic encephalitis, meningitis) may show cerebral atrophy or even no morphological changes. Toxoplasmosis and PML are the most common opportunistic infections typical changes on CT and MR may lead to diagnosis. MR offers advantages compared with CT in its higher sensitivity for the demonstration even of small lesions. (orig.)

  2. [Acquired immunodeficiency syndrome in pediatric patients].

    Molina Moguel, J L; Ruiz Illezcas, R; Forsbach Sánchez, S; Carreño Alvarez, S; Picco Díaz, I

    1990-12-01

    The object of this study was to determine how many of the patients treated at the Pediatric Odontology Clinic, a branch of the Maxillo-Facial Surgery Service at the Veinte de Noviembre Regional Hospital, ISSSTE, are VIH-positive of show serious manifestations of Acquired Immuno-Deficiency Syndrome (AIDS). For such purpose, 100 pediatric patients suffering from different systemic or local diseases were evaluated, the most common being hematological alterations. Results evidenced the presence of VIH in the blood of five of the pediatric subjects, all suffering from Hemophilia. PMID:2132469

  3. Acquired CNS lesions in fetal MRI

    Acquired central nervous system (CNS) lesions are often subtle; therefore, the prenatal diagnosis of these lesions is extremely important. The fetal ultrasound examination and magnetic resonance imaging (MRI) are two important imaging methods that give an insight into these types lesions. The method of choice during pregnancy is still fetal ultrasound; however, fetal MRI is important when there are certain pathologies, e.g. periventricular leukomalacia (PVL) or malformations of the vein of Galen. In this manner clinicians can plan further therapy after childbirth in advance (e.g. cerebral angiography or embolization). (orig.)

  4. Psychological issues in acquired facial trauma

    De Sousa Avinash

    2010-01-01

    Full Text Available The face is a vital component of one′s personality and body image. There are a vast number of variables that influence recovery and rehabilitation from acquired facial trauma many of which are psychological in nature. The present paper presents the various psychological issues one comes across in facial trauma patients. These may range from body image issues to post-traumatic stress disorder symptoms accompanied by anxiety and depression. Issues related to facial and body image affecting social life and general quality of life are vital and the plastic surgeon should be aware of such issues and competent to deal with them in patients and families.

  5. Expert games: means to acquire expert knowledge

    G. Ginkul

    1993-06-01

    Full Text Available This article describes the idea and use of non-traditional technique designed to acquire Expert's knowledge for Expert Systems. The procedures, called "Expert Games", look outwardly as well-known computer "playthings" and at the same time are strong means for Knowledge Acquisition. If Expert wants to succeed, he must to use his professional knowledge. After analyzing game operations of an Expert it is possible to resolve reverse problem - to define which what kind of knowledge have been used for making Expert's decision during the game.

  6. Interactive Effects of Elevated CO2 and Growth Temperature on the Tolerance of Photosynthesis to Acute Heat Stress in C3 and C4 Species

    E. William Hamilton Ⅲ; Scott A. Heckathorn; Puneet Joshi; Dan Wang; Deepak Barua

    2008-01-01

    Determining effects of elevated CO2 on the tolerance of photosynthesis to acute heat-stress (heat wave) is necessary for predicting plant responses to global warming, as photosynthesis is thermolabile and acute heat-stress and atmospheric CO2 will increase in the future. Few studies have examined this, and past results are variable, which may be due to methodological variation. To address this, we grew two C3 and two C4 species at current or elevated CO2 and three different growth temperatures (GT). We assessed photosynthetic thermotolerance in both unacclimated (basal tolerance) and preheat-stressed (preHS = acclimated) plants. In C3 species, basal thermotolerance of net photosynthesis (Pn) was increased In high CO2, but in C4 species, Pn thermotlerance was decreased by high CO2 (except Zea maya at low GT); CO2 effects in preHS plants were mostly small or absent, though high CO2 was detrimental in one C3 and one C4 species at warmer GT. Though high CO2 generally decreased stomatal conductance, decreases in Pn during heat stress were mostly due to non-stomatal effects. Photosystem II (PSII) efficiency was often decreased by high CO2 during heat stress, especially at high GT; CO2 effects on post-PSll electron transport were variable. Thus, high CO2 often affected photosynthetic theromotolerance, and the effects varied with photosynthetic pathway, growth temperature, and acclimation state. Most importantly, in heat-stressed plants at normal or warmer growth temperatures, high CO2 may often decrease, or not benefit as expected, tolerance of photosynthesis to acute heat stress. Therefore, interactive effects of elevated CO2 and warmer growth temperatures on acute heat tolerance may contribute to future changes in plant productivity, distribution, and diversity.

  7. Heat Stress

    ... Publications and Products Programs Contact NIOSH NIOSH HEAT STRESS Recommend on Facebook Tweet Share Compartir NEW Criteria ... hot environments may be at risk of heat stress. Exposure to extreme heat can result in occupational ...

  8. Tetracycline resistance genes acquired at birth.

    Alicea-Serrano, Angela M; Contreras, Mónica; Magris, Magda; Hidalgo, Glida; Dominguez-Bello, Maria G

    2013-06-01

    Newborns acquire their first microbiota at birth. Maternal vaginal or skin bacteria colonize newborns delivered vaginally or by C-section, respectively (Dominguez-Bello et al. 2010 #884). We aimed to determine differences in the presence of four tetracycline (tet) resistance genes, in the microbes of ten newborns and in the mouth and vagina of their mothers, at the time of birth. DNA was amplified by PCR with primers specific for [tet(M), tet(O), tet(Q), and tet(W)]. Maternal vaginas harbored all four tet resistance genes, but most commonly tet(M) and tet(O) (63 and 38 %, respectively). Genes coding for tet resistance differed by birth mode, with 50 % of vaginally delivered babies had tet(M) and tet(O) and 16 and 13 % of infants born by C-section had tet(O) and tet(W), respectively. Newborns acquire antibiotic resistance genes at birth, and the resistance gene profile varies by mode of delivery. PMID:23483141

  9. Asian elephants acquire inaccessible food by blowing.

    Mizuno, Kaori; Irie, Naoko; Hiraiwa-Hasegawa, Mariko; Kutsukake, Nobuyuki

    2016-01-01

    Many animals acquire otherwise inaccessible food with the aid of sticks and occasionally water. As an exception, some reports suggest that elephants manipulate breathing through their trunks to acquire inaccessible food. Here, we report on two female Asian elephants (Elephas maximus) in Kamine Zoo, Japan, who regularly blew to drive food within their reach. We experimentally investigated this behaviour by placing foods in inaccessible places. The elephants blew the food until it came within accessible range. Once the food was within range, the elephants were increasingly less likely to blow as the distance to the food became shorter. One subject manipulated her blowing duration based on food distance: longer when the food was distant. These results suggest that the elephants used their breath to achieve goals: that is, they used it not only to retrieve the food but also to fine-tune the food position for easy grasping. We also observed individual differences in the elephants' aptitude for this technique, which altered the efficiency of food acquisition. Thus, we added a new example of spontaneous behaviour for achieving a goal in animals. The use of breath to drive food is probably unique to elephants, with their dexterous trunks and familiarity with manipulating the act of blowing, which is commonly employed for self-comfort and acoustic communication. PMID:26541597

  10. Clinicopathological correlation of acquired hyperpigmentary disorders

    Anisha B Patel

    2013-01-01

    Full Text Available Acquired pigmentary disorders are group of heterogenous entities that share single, most significant, clinical feature, that is, dyspigmentation. Asians and Indians, in particular, are mostly affected. Although the classic morphologies and common treatment options of these conditions have been reviewed in the global dermatology literature, the value of histpathological evaluation has not been thoroughly explored. The importance of accurate diagnosis is emphasized here as the underlying diseases have varying etiologies that need to be addressed in order to effectively treat the dyspigmentation. In this review, we describe and discuss the utility of histology in the diagnostic work of hyperpigmentary disorders, and how, in many cases, it can lead to targeted and more effective therapy. We focus on the most common acquired pigmentary disorders seen in Indian patients as well as a few uncommon diseases with distinctive histological traits. Facial melanoses, including mimickers of melasma, are thoroughly explored. These diseases include lichen planus pigmentosus, discoid lupus erythematosus, drug-induced melanoses, hyperpigmentation due to exogenous substances, acanthosis nigricans, and macular amyloidosis.