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51.
Influence of yeast immobilization on fermentation and aldehyde reduction during the production of alcohol-free beer 总被引:1,自引:0,他引:1
Production of alcohol-free beer by limited fermentation is optimally performed in a packed-bed reactor. This highly controllable system combines short contact times between yeast and wort with the reduction of off-flavors to concentrations below threshold values. In the present study, the influence of immobilization of yeast to DEAE-cellulose on sugar fermentation and aldehyde reduction was monitored. Immobilized cells showed higher activities of hexokinase and pyruvate decarboxylase compared to cells grown in batch culture. In addition, a higher glucose flux was observed, with enhanced excretion of main fermentation products, indicating a reduction in the flux of sugar used for biomass production. ADH activity was higher in immobilized cells compared to that in suspended cells. However, during prolonged production a decrease was observed in NAD-specific ADH activity, whereas NADP-specific activity increased in the immobilized cells. The shifts in enzyme activities and glucose flux correlate with a higher in vivo reduction capacity of the immobilized cells. 相似文献
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Ellagic acid mitigates arsenic‐trioxide‐induced mitochondrial dysfunction and cytotoxicity in SH‐SY5Y cells
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Fakiha Firdaus Mohd. Faraz Zafeer Mohammad Waseem Ehraz Anis M. Mobarak Hossain Mohammad Afzal 《Journal of biochemical and molecular toxicology》2018,32(2)
In the current study, neuroprotective significance of ellagic acid (EA, a polyohenol) was explored by primarily studying its antioxidant and antiapoptotic potential against arsenic trioxide (As2O3)‐induced toxicity in SH‐SY5Y human neuroblastoma cell lines. The mitigatory effects of EA with particular reference to cell viability and cytotoxicity, the generation of reactive oxygen species, DNA damage, and mitochondrial dynamics were studied. Pretreatment of SH‐SY5Y cells with EA (10 and 20 μM) for 60 min followed by exposure to 2 μM As2O3 protected the SH‐SY5Y cells against the harmful effects of the second. Also, EA pre‐treated groups expressed improved viability, repaired DNA, reduced free radical generation, and maintained altered mitochondrial membrane potential than those exposed to As2O3 alone. EA supplementation also inhibited As2O3‐induced cytochrome c expression that is an important hallmark for determining mitochondrial dynamics. Thus, the current investigations are more convinced for EA as a promising candidate in modulating As2O3‐induced mitochondria‐mediated neuronal toxicity under in vitro system. 相似文献
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Physiological and biochemical characterization of NERICA‐L‐44: a novel source of heat tolerance at the vegetative and reproductive stages in rice
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Rajeev N Bahuguna Jyoti Jha Madan Pal Divya Shah Lovely MF Lawas Sangeetha Khetarpal Krishna S.V. Jagadish 《Physiologia plantarum》2015,154(4):543-559
The predicted increase in the frequency and magnitude of extreme heat spikes under future climate can reduce rice yields significantly. Rice sensitivity to high temperatures during the reproductive stage is well documented while the same during the vegetative stage is more speculative. Hence, to identify and characterize novel heat‐tolerant donors for both the vegetative and reproductive stages, 71 rice accessions, including approximately 75% New Rice for Africa (NERICAs), were phenotyped across field experiments during summer seasons in Delhi, India, and in a controlled environment study at International Rice Research Institute , Philippines. NERICA‐L‐44 (NL‐44) recorded high seedling survival (52%) and superior growth and greater reproductive success exposed to 42.2°C (sd ± 2.3) under field conditions. NL‐44 and the heat‐tolerant check N22 consistently displayed lower membrane damage and higher antioxidant enzymes activity across leaves and spikelets. NL‐44 recorded 50–60% spikelet fertility, while N22 recorded 67–79% under controlled environment temperature of 38°C (sd ±1.17), although both had about 87% fertility under extremely hot field conditions. N22 and NL‐44, exposed to heat stress (38°C), had similar pollen germination percent and number of pollen tubes reaching the ovary. NL‐44 maintained low hydrogen peroxide production and non‐photochemical quenching (NPQ) with high photosynthesis while N22 avoided photosystem II damage through high NPQ under high‐temperature stress. NL‐44 with its reproductive stage resilience to extreme heat stress, better antioxidant scavenging ability in both vegetative tissue and spikelets and superior yield and grain quality is identified as a novel donor for increasing heat tolerance at both the vegetative and reproductive stages in rice. 相似文献
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Katja J Teerds Federica MF van Dissel-Emiliani Maria P De Miguel Mieke de Boer-Brouwer Lina M Körting Eddy Rijntjes 《Reproductive biology and endocrinology : RB&E》2007,5(1):43-9
Background
The initial steps of stem Leydig cell differentiation into steroid producing progenitor cells are thought to take place independent of luteinizing hormone (LH), under the influence of locally produced factors such as leukaemia inhibitory factor (LIF), platelet derived growth factor A and stem cell factor. For the formation of a normal sized Leydig cell population in the adult testis, the presence of LH appears to be essential. 相似文献57.
LJ Melchers MJAM Clausen MF Mastik L Slagter-Menkema JE van der Wal GBA Wisman JLN Roodenburg E Schuuring 《Epigenetics》2015,10(9):850-860
Hypermethylation is an important mechanism for the dynamic regulation of gene expression, necessary for metastasizing tumour cells. Our aim is to identify methylation tumour markers that have a predictive value for the presence of regional lymph node metastases in patients with oral and oropharyngeal squamous cell carcinoma (OOSCC). Significantly differentially expressed genes were retrieved from four reported microarray expression profiles comparing pN0 and pN+ head-neck tumours, and one expression array identifying functionally hypermethylated genes. Additional metastasis-associated genes were included from the literature. Thus genes were selected that influence the development of nodal metastases and might be regulated by methylation. Methylation-specific PCR (MSP) primers were designed and tested on 8 head-neck squamous cell carcinoma cell lines and technically validated on 10 formalin-fixed paraffin-embedded (FFPE) OOSCC cases. Predictive value was assessed in a clinical series of 70 FFPE OOSCC with pathologically determined nodal status. Five out of 28 methylation markers (OCLN, CDKN2A, MGMT,
MLH1 and DAPK1) were frequently differentially methylated in OOSCC. Of these, MGMT methylation was associated with pN0 status (P = 0.02) and with lower immunoexpression (P = 0.02). DAPK1 methylation was associated with pN+ status (P = 0.008) but did not associate with protein expression. In conclusion, out of 28 candidate genes, two (7%) showed a predictive value for the pN status. Both genes, DAPK1 and MGMT, have predictive value for nodal metastasis in a clinical group of OOSCC. Therefore DNA methylation markers are capable of contributing to diagnosis and treatment selection in OOSCC. To efficiently identify additional new methylation markers, genome-wide methods are needed. 相似文献
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Muhammad Farooq Waleed Anjum Manzoor Hussain Zafeer Saqib Khalid Rasheed Khan Abbas Hussain Shah Sagheer Gul Saira Jabeen 《农业工程》2019,39(1):9-13
The current work was carried out in Upper Tanawal which lies in the mid of Western part of lesser Himalaya. The area lies between 34°0.34.40′ N to 34°0.48.88′ N latitude and 72°0.84.27′ E to 73°0.10.50′ E longitude. Upper Tanawal is rich in biodiversity. No work regarding forest and forest situation is done previously in this area. (Farooq, et al., 2017). The area was once housing notable and thick forest strands famous for their habitat uniqueness to harbor number of pheasant and other wildlife species. Due to security reasons and worse situation of law and order compromising government writ the area remained scientifically as well departmentally neglected resulting rapid and vigorous ruthless deforestation. The area was extensively visited and sampled using Quadrate method for phytosociological data collection. Phytosociological attributes like density, cover, and frequency were also Calculated and recorded for all tree species of the area in each quadrat. Altitude, slope angle, atmospheric humidity and temperature were also considered as environmental variables for each sampling site. Results reflect that Upper Tanawal hosts 52 different tree species of 39 genera belonging to 25 tree families.The important forests of Upper Tanawal are under high anthropogenic and environmental disturbances. Some of them may easily be managed because of the presence of large number of seedling; however, some areas need serious attention. It was observed that Pinus roxburghii and Pinus wallichiana are the potential tree species for reforestation and afforestation in the area. This study will be the baseline for new researchers in the study area. 相似文献
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Purification and characterization of a high-molecular-weight form of recombinant human Interleukin-2
Zafeer Ahmad Doreen Ciolek Yu-Ching E. Pan Hanspeter Michel Fazal R. Khan 《Journal of Protein Chemistry》1994,13(7):591-598
During purification of recombinant Interleukin-2 (rIL-2) by reversed-phase HPLC, early fractions are discarded due to the presence of an unidentified form of rIL-2. A procedure has been developed to isolate and purify this unidentified form of rIL-2. The purification process involves two chromatography steps and utilizes a Bakerbond Carboxy-Sulfon (CS) column under two different conditions. This material, designated as a high-molecular-weight form of rIL-2 (HMWrIL-2), exhibits lower mobility during SDS-PAGE and has apI which is approximately one unit less than that of rIL-2, but has similar bioactivity to rIL-2. Structural analysis through enzymatic cleavage, HPLC peptide mapping, mass spectrometry, sequencing, and amino acid composition revealed that the difference between these two proteins is a C-terminal extension of 11 amino acids. This extension could be the result of a nonstandard translation event. 相似文献
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