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991.
Frederico Magalhães Kristoffer Krogerus Virve Vidgren Mari Sandell Brian Gibson 《Journal of industrial microbiology & biotechnology》2017,44(8):1203-1213
Yeast cryotolerance may be advantageous for cider making, where low temperatures are usually employed. Here, we crossed the cryotolerant S. eubayanus with a S. cerevisiae wine strain and assessed the suitability of the hybrids for low-temperature cider fermentation. All strains fermented the juice to 5% ABV, but at different rates; hybrid strains outperformed S. cerevisiae, which was sensitive to low temperatures. The best hybrid fermented similarly to S. eubayanus. S. eubayanus produced sulphurous off flavours which masked a high concentration of fruity ester notes. This phenotype was absent in the hybrid strains, resulting in distinctly fruitier ciders. Aroma was assessed by an independent consumer panel, which rated the hybrid ciders as identical to the wine strain cider. Both were significantly more pleasant than the S. eubayanus cider. Interspecific hybridization can apparently be used effectively to improve low-temperature fermentation performance without compromising product quality. 相似文献
992.
Transient trade‐off between climate benefit and biodiversity loss of harvesting stumps for bioenergy 下载免费PDF全文
Tord Snäll Victor Johansson Mari Jönsson Carina Ortiz Torun Hammar Alexandro Caruso Måns Svensson Johan Stendahl 《Global Change Biology Bioenergy》2017,9(12):1751-1763
To replace fossil fuel and thereby mitigate climate change, harvesting of wood such as stumps for bioenergy will likely increase. Coarse deadwood is an important resource for biodiversity and stumps comprise the main part of the coarse deadwood in managed forests. We provide the first integrated analysis of the long‐term climate and biodiversity impacts of a whole landscape. We simultaneously project climate and biodiversity impacts of harvesting stumps to substitute for fossil coal, assuming scenarios with different proportions of the landscape with stump harvest (10, 50, 80%) the coming 50 years. A life cycle approach was used to calculate future global temperature changes and future metapopulation changes in six epixylic lichens. Metapopulation dynamics were projected using colonization and extinction models based on times series data. Harvesting stumps from ≥50% of the clear‐cut forest land benefits climate with a net global temperature reduction >0.5·10?9 K ha?1 after 50 years if assuming substitution of fossil coal. For all scenarios, using stump bioenergy leads to immediate (within 1 year) reductions in temperature of 50% compared to using fossil coal, increasing to 70% reduction after 50 years. However, large‐scale stump harvest inflicted substantial metapopulation declines for five of six lichens. High stump harvest levels (≥50%) put common lichens at risk of becoming red‐listed following the IUCN criteria. The net temperature reduction (cooling effect) from substituting fossil coal with stumps harvested for bioenergy increased over time, while lichen metapopulations stabilized at lower equilibria after two to three decades. This indicates that trade‐offs between climate and metapopulations of commons species are transient, where climate benefits become more prevalent in the long term. As both objectives are important for meeting (inter‐)national climate and biodiversity targets, integrated analyses such as this should be encouraged and urged to guide policymaking about large‐scale implementation of stump harvest. 相似文献
993.
Jussi Pihlajamki Mari Ylinen Pauli Karhap Ilkka Vauhkonen Markku Laakso 《Obesity (Silver Spring, Md.)》2003,11(7):912-917
Objective: Promoter polymorphisms of the tumor necrosis factor alpha (TNF‐α) gene are associated with insulin sensitivity and BMI. We investigated whether the effect of the G‐308A polymorphism of the TNF‐α gene on insulin action depends on BMI. Research Methods and Procedures: The effects of the G‐308A polymorphism on the rates of glucose and lipid oxidation and free fatty acid (FFA) levels were studied using the hyperinsulinemic euglycemic clamp combined with indirect calorimetry in 129 healthy subjects. Results: The ?308A allele of the TNF‐α gene was associated with high rates of glucose oxidation (p = 0.008 adjusted for age, gender, and BMI) and lipid synthesis (p = 0.037) and suppression of FFA levels (p = 0.023) during hyperinsulinemia. In normal weight subjects (BMI < 26 kg/m2), the ?308 allele was associated with high rates of glucose oxidation (p = 0.036) during the clamp but not with high rates of lipid synthesis (p = 0.896) or FFA suppression (p = 0.464). In overweight subjects (BMI ≥ 26 kg/m2), high rates of lipid synthesis and FFA suppression (p = 0.010 and p = 0.042, respectively) but not the rates of glucose oxidation during the clamp (p = 0.193) were associated with the ?308A allele. Discussion: The ?308A allele of the promoter of the TNF‐α gene is associated with high rates of glucose oxidation in normal weight subjects and with effective lipid storage in overweight subjects. These findings suggest an interaction of the polymorphism with obesity. 相似文献
994.
Differential expression of granulysin and perforin by NK cells in cancer patients and correlation of impaired granulysin expression with progression of cancer 总被引:13,自引:0,他引:13
Atsuko Kishi Yasushi Takamori Kazuyuki Ogawa Shoichi Takano Shuji Tomita Mari Tanigawa Makiko Niman Tsunataro Kishida Setsuya Fujita 《Cancer immunology, immunotherapy : CII》2002,50(11):604-614
Granulysin has been identified as an effector molecule co-localized with perforin in the cytotoxic granules of cytotoxic T lymphocytes and natural killer (NK) cells, and has been reported to kill intracellular pathogens in infected cells in the presence of perforin and to induce a cytotoxic effect against tumor cells. The aim of the present study was to elucidate whether intracellular expression of granulysin and perforin by NK cells might be associated with progression of cancer. Flow cytometric analysis demonstrated high levels of perforin and granulysin expression by CD3(-) CD16(+) cells in healthy controls. In contrast, cancer patients exhibited significantly decreased levels of granulysin expression ( P<0.005), despite having equally high levels of perforin expression in comparison with healthy controls. The tumor-free patients expressed granulysin at levels similar to healthy controls, while the progressive tumor-bearing patients expressed remarkably lower levels of granulysin compared to healthy controls ( P<0.0001). Similarly, patients with an advanced performance status had significantly fewer granulysin-positive NK cells than healthy controls. Meanwhile, a considerable number of the tumor-bearing patients showed a decrease in the number of circulating NK cells, and a correlation between impaired granulysin expression and reduced circulating NK cells was observed. These findings suggest that the tumor-bearing patients with impaired granulysin expression were in an immunosuppressive state. In conclusion, impaired expression of granulysin by NK cells correlates with progression of cancer, and determination of granulysin expression might prove informative for assessing the immunological condition of cancer patients. 相似文献
995.
Characterization of Secretory Genes ypt1/yptA and nsf1/nsfA from Two Filamentous Fungi: Induction of Secretory Pathway Genes of Trichoderma reesei under Secretion Stress Conditions 下载免费PDF全文
996.
Mari McCrossan Miriam Windsor Sreenivasan Ponnambalam John Armstrong Thomas Wileman 《Journal of virology》2001,75(23):11755-11765
The cellular secretory pathway is important during the assembly and envelopment of viruses and also controls the transport of host proteins, such as cytokines and major histocompatibility proteins, that function during the elimination of viruses by the immune system. African swine fever virus (ASFV) encodes at least 26 proteins with stretches of hydrophobic amino acids suggesting entry into the secretory pathway (R. J. Yanez, J. M. Rodriguez, M. L. Nogal, L. Yuste, C. Enriquez, J. F. Rodriguez, and E. Vinuela, Virology 208:249-278, 1995). To predict how and where these potential membrane proteins function, we have studied the integrity of the secretory pathway in cells infected with ASFV. Remarkably, ASFV caused complete loss of immunofluorescence signal for the trans Golgi network (TGN) marker protein TGN46 and dispersed the AP1 TGN adapter complex. Loss of TGN46 signal was not due to degradation of TGN46, suggesting redistribution of TGN46 to other membrane compartments. ASFV markedly slowed transport of cathepsin D to lysosomes, demonstrating that loss of TGN structure correlated with loss of TGN function. ASFV shows a tropism for macrophages, and it is possible that ASFV compromises TGN function to augment the activity of viral membrane proteins or to suppress the function of host immunoregulatory proteins. 相似文献
997.
Is nonparental egg carrying parental care? 总被引:2,自引:2,他引:0
998.
The population sex ratio, spatial distribution, relative growth rate, canopy size and morphology, and nitrogen content of leaves of male and female individuals were compared in seven populations of the dioecious shrubPistacia lentiscus L. occurring in different localities of the Serra da Arrábida Natural Park, Portugal. The expected pattern of male preponderance in stressful habitats was tested. Less perturbed areas, with a well developed vegetation cover, had male-biased sex ratios, while in former agricultural areas there were no significant differences between the number of male and female plants. Our results failed to reveal any significant differences in the morphological variables between sexes except in the number of basal stems. Male plants also had a significantly higher chlorophyll content (chl a+b) than female plants. But when plants were sorted into large and small individuals, larger plants showed a significantly higher leaf area index and a significantly higher number of basal stems. There were no significant differences in the leaf nitrogen content between male and female plants from June to August, but such differences appeared (P<0.001) in September and October corresponding to the production of mature fruits. Differences in sex-ratio may be explained by different resource allocation patterns of the two sexes, which favoured male plants in the less perturbed environments. In agricultural areas farmers could also have favoured female plants in former times. 相似文献
999.
Jordan Golubov Luis E. Eguiarte Mari´a C. Mandujano Jorge Lo´pez-Portillo Carlos Montana 《American journal of botany》1999,86(7):955-963
Populations of Prosopis glandulosa var. torreyana in the Chihuahuan desert have a fixed dimorphic system of nectar production in which half the individuals produce nectar (are nectarful) and the other half are nectarless. We analyzed the impact of nectar production on different estimates of fitness, comparing nectarful against nectarless individuals in size, mating system, seed traits, and fruit set in a 1-ha scrubland. Of the reproductive individuals (358), 46% were nectarful and 54% were nectarless. Neither tree size nor flowering phenology differed between nectar morphs. Fixation indices (F) for both progeny (F = −0.2) and adults (F = −0.45) were negative, and high heterozygosities were found in adults and progeny (H = 0.45). No differences were found between nectar morphs for F, H, and single (ts = 1.1) and multilocus (tm = 1.03) outcrossing rates. Controlled pollinations showed differences between selfing and control treatments with no differences between nectar morphs. Nectarless individuals produced significantly more pollen grains than did nectar producers, but all other measured floral traits showed no differences. Nectarful trees were visited by pollinators 21 times more often and had a significantly higher overall fruit set than did nectarless trees. No differences between nectar morphs in seed mass or in percentage seed germination were found, but heavier seeds tended to have higher heterozygosities. Both morphs had similar success as females, but nectarless trees had ∼7% higher male function. We discuss three possible scenarios for the evolution of the fixed dimorphism in nectar production, two involving unstable phases (substitution of one morph by the other, and evolution towards dioecy) and one stable scenario (maintenance of the dimorphic system). 相似文献
1000.
Tissue-Specific Somatic Mosaicism in Spinal and Bulbar Muscular Atrophy Is Dependent on CAG-Repeat Length and Androgen Receptor–Gene Expression Level 下载免费PDF全文
Fumiaki Tanaka Matthew F. Reeves Yasuhiro Ito Michiyo Matsumoto Mei Li Shigeru Miwa Akira Inukai Masahiko Yamamoto Manabu Doyu Mari Yoshida Yoshio Hashizume Shin-ichi Terao Terunori Mitsuma Gen Sobue 《American journal of human genetics》1999,65(4):966-973
The factors influencing the tissue-specific pattern of somatic mosaicism in CAG-repeat diseases have not yet been fully resolved. We performed a detailed analysis of the degree of somatic mosaicism in various tissues from 20 patients with spinal and bulbar muscular atrophy (SBMA), including 4 who were deceased. The most outstanding feature was the prominent somatic mosaicism observed in the cardiac and skeletal muscles, composed predominantly of postmitotic cells, and in the skin, prostate, and testis. The CNS tissues, liver, and spleen showed the least mosaicism. The tissue distribution of somatic mosaicism in patients with SBMA was markedly different from that in patients with Huntington disease (HD) and from that in patients with dentatorubral-pallidoluysian atrophy (DRPLA). The degree of somatic mosaicism correlated with the CAG-repeat number but not with age at examination. Furthermore, tissues with a higher mosaicism level corresponded well to those with a higher expression level of androgen receptor protein. The tissue-specific pattern of somatic mosaicism related not only to cell composition with different cell turnover rates but to repeat size and gene expression levels, and postnatal cell division is unlikely to be a major cause of somatic mosaicism probably because of the relative stability of CAG repeat in SBMA. 相似文献