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Effects of chilling on tomato fruit texture 总被引:1,自引:0,他引:1
The effects of chilling on tomato ( Lycopersicon esculentum Mill cv. Caruso) texture were investigated using fruit stored at 22°C (nonchilled) or 5°C (chilled) for 28 days. or at 5°C for 15 days before transfer to 22°C to facilitate ripening during and additional 13 days (prechilled). Prechilled fruit exhibited symptoms of slight chilling injury, i.e. development of mealiness, accelerated softening relative to that of nonchilled fruit and nonuniform surface colour development. The firmness of all fruit decreased during ripening and chilled storage when measured by flat plate compression and puncture, especially during the early stages of ripening of nonchilled and prechilled fruit. The compression firmness of pericarp tissue similarly decreased during ripening of nonchilled and prechilled fruit, but was maintained during chilling. Total moisture content (ca 94%) of tissue, uronide content (32-35% w/w) and extracted β-galactosidase activity did not differ significantly ( P > 0.05) among fruit during ripening and chilled storage. The degree of uronide methyl esterification in ethanol-insoluble solids prepared from pericarp tissue (EIS) was relatively low for all fruit. i.e. <40%. EIS from which greater levels of pectinesterase were extracted (i.e. nonchilled>chilled>prechilled) exhibited decreased levels of uronide methyl esterification. Markedly elevated levels of β-glucosidase activity were extracted from prechilled EIS. Total polygalacturonase activity (mainly as PGI) and autolysis of enzyme-extracted EIS were inversely correlated ( P ≤ 0.05) only with the loss of nonchilled fruit and tissue firmness and prechilled fruit firmness. Results suggest a possible role for β-glucosidase in textural changes of prechilled fruit and tissue (e.g. loss of firmness, development of mealiness) and also implicate loss of skin strength in the softening of whole fruit during chilling. 相似文献
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Soledad Gaitán Elvira Cuenllas Pilar Sancho Juan A. Bueren Concepción Tejero 《Bioscience reports》1992,12(4):281-292
This paper analyzes the long-term (6 and 12 months) function of mouse granulocytes after total body irradiation with a single dose (5 Gy) of X-rays. Superoxide anion production has been investigated in granulocytes from peripheral blood, and also in those harvested from long term bone marrow cultures, with the aim of correlating the environmental damage induced by radiation with the functional properties of granulocytes. Anin vivo andin vitro enhancement of superoxide anion production and protein levels in granulocytes from irradiated mice is described. The presence of some colony stimulating factor in the supernatant of cultures from irradiated mice could play an important role in the priming of granulocytes. 相似文献
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Bombesin production by human small cell carcinoma of the lung 总被引:5,自引:0,他引:5
G D Sorenson S R Bloom M A Ghatei S A Del Prete C C Cate O S Pettengill 《Regulatory peptides》1982,4(2):59-66
A series of continuous cell lines of human small cell carcinoma of the lung (SCCL) have been evaluated for the production of bombesin (BN). In early established cultures BN was detected in the medium of 9 out of 11 cell lines and in 6 out of 7 cell homogenates examined. Levels in the medium were frequently higher in cultures of later passages compared to earlier passages of the same line and low levels developed in the two previously negative cell lines. Plasma concentrations were greater than 80 pmol/l in 2 out of 27 (7%) randomly selected patients with SCCL. A culture (DMS 406) established from the tumor of a patient with the highest plasma level (1240 pmol/l) was the highest producer in vitro. The results indicate that BN, which has been demonstrated immunocytochemically to be present in normal bronchial mucosal cells, is frequently produced by SCCL in vitro but elevated plasma levels are infrequently found in patients with this neoplasm. 相似文献
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SeyyedReza SadatEbrahimi Hassan Amini Reza Rahbarghazi Paria Habibollahi Shahrouz Ghaderi Hadi Rajabi Aysa Rezabakhsh 《Journal of cellular and molecular medicine》2022,26(11):3120
Recently, cytokines belonging to C1q/tumour necrosis factor‐related proteins (CTRPs) superfamily have attracted increasing attention due to multiple metabolic functions and desirable anti‐inflammatory effects. These various molecular effectors exhibit key roles upon the onset of cardiovascular diseases, making them novel adipo/cardiokines. This review article aimed to highlight recent findings correlated with therapeutic effects and additional mechanisms specific to the CTRP9, particularly in cardiac ischaemia/reperfusion injury (IRI). Besides, the network of the CTPR9 signalling pathway and its possible relationship with IRI were discussed. Together, the discovery of all involved underlying mechanisms could shed light to alleviate the pathological sequelae after the occurrence of IRI. 相似文献
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J. Jansen M. Fedecostante M.J. Wilmer L.P. van den Heuvel J.G. Hoenderop R. Masereeuw 《Biotechnology advances》2014
With the world-wide increase of patients with renal failure, the development of functional renal replacement therapies have gained significant interest and novel technologies are rapidly evolving. Currently used renal replacement therapies insufficiently remove accumulating waste products, resulting in the uremic syndrome. A more preferred treatment option is kidney transplantation, but the shortage of donor organs and the increasing number of patients waiting for a transplant warrant the development of novel technologies. The bioartificial kidney (BAK) is such promising biotechnological approach to replace essential renal functions together with the active secretion of waste products. The development of the BAK requires a multidisciplinary approach and evolves at the intersection of regenerative medicine and renal replacement therapy. Here we provide a concise review embracing a compact historical overview of bioartificial kidney development and highlighting the current state-of-the-art, including implementation of living-membranes and the relevance of extracellular matrices. We focus further on the choice of relevant renal epithelial cell lines versus the use of stem cells and co-cultures that need to be implemented in a suitable device. Moreover, the future of the BAK in regenerative nephrology is discussed. 相似文献
30.
Graham DI Gentleman SM Nicoll JA Royston MC McKenzie JE Roberts GW Mrak RE Griffin WS 《Cellular and molecular neurobiology》1999,19(1):19-30
1. Alzheimer's disease is a heterogeneous disorder that may be caused by genetic or environmental factors or by a combination of both. Abnormalities in chromosomes 1, 14, and 21 have all been implicated in the pathogenesis of the early-onset form of the disease, while the 4 allele of the apolipoprotein E gene (on chromosome 19) is now recognized as a risk factor for early- and late-onset sporadic and familial Alzheimer's disease.2. The best-established environmental trigger for the disease is a head injury, based on epidemiological and neuropathological evidence. Approximately 30% of patients who die after a single episode of severe head injury show intracerebral deposition of -amyloid protein (A), a protein that is thought to be central to the pathogenesis of Alzheimer's disease.3. Recent studies have revealed an over-representation of the apoE 4 allele in those head-injured patients displaying A pathology, thus providing the first evidence for a link between a genetic susceptibility (apoE 4) and an environmental trigger (head injury) in the development of Alzheimer-type pathology. 相似文献